lib: import ccan modules for tdb2

Imported from git://git.ozlabs.org/~ccan/ccan init-1161-g661d41f

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>

135 files changed, 13875 insertions, 1 deletions

diff --git a/lib/ccan/array_size/LICENSE b/lib/ccan/array_size/LICENSE
new file mode 100644
index 0000000000..5522aa5f33
--- /dev/null
+++ b/lib/ccan/array_size/LICENSE
@@ -0,0 +1,508 @@
+
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diff --git a/lib/ccan/array_size/_info b/lib/ccan/array_size/_info
new file mode 100644
index 0000000000..af7ef1cfd2
--- /dev/null
+++ b/lib/ccan/array_size/_info
@@ -0,0 +1,46 @@
+#include <stdio.h>
+#include <string.h>
+#include "config.h"
+
+/**
+ * array_size - routine for safely deriving the size of a visible array.
+ *
+ * This provides a simple ARRAY_SIZE() macro, which (given a good compiler)
+ * will also break compile if you try to use it on a pointer.
+ *
+ * This can ensure your code is robust to changes, without needing a gratuitous
+ * macro or constant.
+ *
+ * Example:
+ *	// Outputs "Initialized 32 values"
+ *	#include <ccan/array_size/array_size.h>
+ *	#include <stdlib.h>
+ *	#include <stdio.h>
+ *
+ *	// We currently use 32 random values.
+ *	static unsigned int vals[32];
+ *
+ *	int main(void)
+ *	{
+ *		unsigned int i;
+ *		for (i = 0; i < ARRAY_SIZE(vals); i++)
+ *			vals[i] = random();
+ *		printf("Initialized %u values\n", i);
+ *		return 0;
+ *	}
+ *
+ * License: LGPL (2 or any later version)
+ * Author: Rusty Russell <rusty@rustcorp.com.au>
+ */
+int main(int argc, char *argv[])
+{
+	if (argc != 2)
+		return 1;
+
+	if (strcmp(argv[1], "depends") == 0) {
+		printf("ccan/build_assert\n");
+		return 0;
+	}
+
+	return 1;
+}
diff --git a/lib/ccan/array_size/array_size.h b/lib/ccan/array_size/array_size.h
new file mode 100644
index 0000000000..0876945c5e
--- /dev/null
+++ b/lib/ccan/array_size/array_size.h
@@ -0,0 +1,25 @@
+#ifndef CCAN_ARRAY_SIZE_H
+#define CCAN_ARRAY_SIZE_H
+#include "config.h"
+#include <ccan/build_assert/build_assert.h>
+
+/**
+ * ARRAY_SIZE - get the number of elements in a visible array
+ * @arr: the array whose size you want.
+ *
+ * This does not work on pointers, or arrays declared as [], or
+ * function parameters.  With correct compiler support, such usage
+ * will cause a build error (see build_assert).
+ */
+#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof((arr)[0]) + _array_size_chk(arr))
+
+#if HAVE_BUILTIN_TYPES_COMPATIBLE_P && HAVE_TYPEOF
+/* Two gcc extensions.
+ * &a[0] degrades to a pointer: a different type from an array */
+#define _array_size_chk(arr)						\
+	BUILD_ASSERT_OR_ZERO(!__builtin_types_compatible_p(typeof(arr),	\
+							typeof(&(arr)[0])))
+#else
+#define _array_size_chk(arr) 0
+#endif
+#endif /* CCAN_ALIGNOF_H */
diff --git a/lib/ccan/array_size/test/compile_fail-function-param.c b/lib/ccan/array_size/test/compile_fail-function-param.c
new file mode 100644
index 0000000000..cb64d98424
--- /dev/null
+++ b/lib/ccan/array_size/test/compile_fail-function-param.c
@@ -0,0 +1,24 @@
+#include <ccan/array_size/array_size.h>
+#include <stdlib.h>
+
+struct foo {
+	unsigned int a, b;
+};
+
+int check_parameter(const struct foo array[4]);
+int check_parameter(const struct foo array[4])
+{
+#ifdef FAIL
+	return (ARRAY_SIZE(array) == 4);
+#if !HAVE_TYPEOF || !HAVE_BUILTIN_TYPES_COMPATIBLE_P
+#error "Unfortunately we don't fail if _array_size_chk is a noop."
+#endif
+#else
+	return sizeof(array) == 4 * sizeof(struct foo);
+#endif
+}
+
+int main(int argc, char *argv[])
+{
+	return check_parameter(NULL);
+}
diff --git a/lib/ccan/array_size/test/compile_fail.c b/lib/ccan/array_size/test/compile_fail.c
new file mode 100644
index 0000000000..37d315f219
--- /dev/null
+++ b/lib/ccan/array_size/test/compile_fail.c
@@ -0,0 +1,14 @@
+#include <ccan/array_size/array_size.h>
+
+int main(int argc, char *argv[8])
+{
+	char array[100];
+#ifdef FAIL
+	return ARRAY_SIZE(argv) + ARRAY_SIZE(array);
+#if !HAVE_TYPEOF || !HAVE_BUILTIN_TYPES_COMPATIBLE_P
+#error "Unfortunately we don't fail if _array_size_chk is a noop."
+#endif
+#else
+	return ARRAY_SIZE(array);
+#endif
+}
diff --git a/lib/ccan/array_size/test/run.c b/lib/ccan/array_size/test/run.c
new file mode 100644
index 0000000000..37b4200b44
--- /dev/null
+++ b/lib/ccan/array_size/test/run.c
@@ -0,0 +1,33 @@
+#include <ccan/array_size/array_size.h>
+#include <ccan/tap/tap.h>
+
+static char array1[1];
+static int array2[2];
+static unsigned long array3[3][5];
+struct foo {
+	unsigned int a, b;
+	char string[100];
+};
+static struct foo array4[4];
+
+/* Make sure they can be used in initializers. */
+static int array1_size = ARRAY_SIZE(array1);
+static int array2_size = ARRAY_SIZE(array2);
+static int array3_size = ARRAY_SIZE(array3);
+static int array4_size = ARRAY_SIZE(array4);
+
+int main(int argc, char *argv[])
+{
+	plan_tests(8);
+	ok1(array1_size == 1);
+	ok1(array2_size == 2);
+	ok1(array3_size == 3);
+	ok1(array4_size == 4);
+
+	ok1(ARRAY_SIZE(array1) == 1);
+	ok1(ARRAY_SIZE(array2) == 2);
+	ok1(ARRAY_SIZE(array3) == 3);
+	ok1(ARRAY_SIZE(array4) == 4);
+
+	return exit_status();
+}
diff --git a/lib/ccan/asearch/LICENSE b/lib/ccan/asearch/LICENSE
new file mode 100644
index 0000000000..5522aa5f33
--- /dev/null
+++ b/lib/ccan/asearch/LICENSE
@@ -0,0 +1,508 @@
+
+                  GNU LESSER GENERAL PUBLIC LICENSE
+                       Version 2.1, February 1999
+
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diff --git a/lib/ccan/asearch/_info b/lib/ccan/asearch/_info
new file mode 100644
index 0000000000..857475016f
--- /dev/null
+++ b/lib/ccan/asearch/_info
@@ -0,0 +1,58 @@
+#include <stdio.h>
+#include <string.h>
+#include "config.h"
+
+/**
+ * asearch - typesafe binary search (bsearch)
+ *
+ * An ordered array of objects can be efficiently searched using a binary
+ * search algorithm; the time taken is around log(number of elements).
+ *
+ * This version uses macros to be typesafe on platforms which support it.
+ *
+ * License: LGPL
+ * Author: Rusty Russell <rusty@rustcorp.com.au>
+ *
+ * Example:
+ *	#include <ccan/asearch/asearch.h>
+ *	#include <stdio.h>
+ *	#include <string.h>
+ *
+ *	static int cmp(const char *key, char *const *elem)
+ *	{
+ *		return strcmp(key, *elem);
+ *	}
+ *
+ *	int main(int argc, char *argv[])
+ *	{
+ *		char **p;
+ *
+ *		if (argc < 2) {
+ *			fprintf(stderr, "Usage: %s <key> <list>...\n"
+ *				"Print position of key in (sorted) list\n",
+ *				argv[0]);
+ *			exit(1);
+ *		}
+ *
+ *		p = asearch(argv[1], &argv[2], argc-2, cmp);
+ *		if (!p) {
+ *			printf("Not found!\n");
+ *			return 1;
+ *		}
+ *		printf("%u\n", p - &argv[2]);
+ *		return 0;
+ *	}
+ */
+int main(int argc, char *argv[])
+{
+	if (argc != 2)
+		return 1;
+
+	if (strcmp(argv[1], "depends") == 0) {
+		printf("ccan/typesafe_cb\n");
+		printf("ccan/array_size\n");
+		return 0;
+	}
+
+	return 1;
+}
diff --git a/lib/ccan/asearch/asearch.h b/lib/ccan/asearch/asearch.h
new file mode 100644
index 0000000000..d252284e7d
--- /dev/null
+++ b/lib/ccan/asearch/asearch.h
@@ -0,0 +1,37 @@
+#ifndef CCAN_ASEARCH_H
+#define CCAN_ASEARCH_H
+#include <stdlib.h>
+#include <ccan/typesafe_cb/typesafe_cb.h>
+
+/**
+ * asearch - search an array of elements
+ * @key: pointer to item being searched for
+ * @base: pointer to data to sort
+ * @num: number of elements
+ * @cmp: pointer to comparison function
+ *
+ * This function does a binary search on the given array.  The
+ * contents of the array should already be in ascending sorted order
+ * under the provided comparison function.
+ *
+ * Note that the key need not have the same type as the elements in
+ * the array, e.g. key could be a string and the comparison function
+ * could compare the string with the struct's name field.  However, if
+ * the key and elements in the array are of the same type, you can use
+ * the same comparison function for both sort() and asearch().
+ */
+#if HAVE_TYPEOF
+#define asearch(key, base, num, cmp)					\
+	((__typeof__(*(base))*)(bsearch((key), (base), (num), sizeof(*(base)), \
+		typesafe_cb_cast(int (*)(const void *, const void *),	\
+				 int (*)(const __typeof__(*(key)) *,	\
+					 const __typeof__(*(base)) *),	\
+				 (cmp)))))
+
+#else
+#define asearch(key, base, num, cmp)				\
+	(bsearch((key), (base), (num), sizeof(*(base)),		\
+		 (int (*)(const void *, const void *))(cmp)))
+#endif
+
+#endif /* CCAN_ASEARCH_H */
diff --git a/lib/ccan/asearch/test/compile_fail-return-value-const.c b/lib/ccan/asearch/test/compile_fail-return-value-const.c
new file mode 100644
index 0000000000..2edee93501
--- /dev/null
+++ b/lib/ccan/asearch/test/compile_fail-return-value-const.c
@@ -0,0 +1,25 @@
+#include <ccan/asearch/asearch.h>
+#include <ccan/array_size/array_size.h>
+#include <string.h>
+
+static int cmp(const char *key, const char *const *elem)
+{
+	return strcmp(key, *elem);
+}
+
+int main(void)
+{
+	const char key[] = "key";
+	const char *elems[] = { "a", "big", "list", "of", "things" };
+
+#ifdef FAIL
+	char **p;
+#if !HAVE_TYPEOF
+#error "Unfortunately we don't fail if no typeof."
+#endif
+#else
+	const char **p;
+#endif
+	p = asearch(key, elems, ARRAY_SIZE(elems), cmp);
+	return p ? 0 : 1;
+}
diff --git a/lib/ccan/asearch/test/compile_fail-return-value.c b/lib/ccan/asearch/test/compile_fail-return-value.c
new file mode 100644
index 0000000000..4aef5327a8
--- /dev/null
+++ b/lib/ccan/asearch/test/compile_fail-return-value.c
@@ -0,0 +1,22 @@
+#include <ccan/asearch/asearch.h>
+
+static int cmp(const char *key, char *const *elem)
+{
+	return 0;
+}
+
+int main(int argc, char **argv)
+{
+	const char key[] = "key";
+
+#ifdef FAIL
+	int **p;
+#if !HAVE_TYPEOF
+#error "Unfortunately we don't fail if no typeof."
+#endif
+#else
+	char **p;
+#endif
+	p = asearch(key, argv+1, argc-1, cmp);
+	return p ? 0 : 1;
+}
diff --git a/lib/ccan/asearch/test/run-strings.c b/lib/ccan/asearch/test/run-strings.c
new file mode 100644
index 0000000000..3ec453842f
--- /dev/null
+++ b/lib/ccan/asearch/test/run-strings.c
@@ -0,0 +1,22 @@
+#include <ccan/asearch/asearch.h>
+#include <ccan/array_size/array_size.h>
+#include <ccan/tap/tap.h>
+#include <stdlib.h>
+
+static int cmp(const int *key, const char *const *elem)
+{
+	return *key - atoi(*elem);
+}
+
+int main(void)
+{
+	const char *args[] = { "1", "4", "7", "9" };
+	int key = 7;
+	const char **p;
+
+	plan_tests(1);
+	p = asearch(&key, args, ARRAY_SIZE(args), cmp);
+	ok1(p == &args[2]);
+
+	return exit_status();
+}
diff --git a/lib/ccan/asearch/test/run.c b/lib/ccan/asearch/test/run.c
new file mode 100644
index 0000000000..2a896fccfe
--- /dev/null
+++ b/lib/ccan/asearch/test/run.c
@@ -0,0 +1,40 @@
+#include <ccan/asearch/asearch.h>
+#include <ccan/array_size/array_size.h>
+#include <ccan/tap/tap.h>
+#include <limits.h>
+
+static int test_cmp(const int *key, const int *elt)
+{
+	if (*key < *elt)
+		return -1;
+	else if (*key > *elt)
+		return 1;
+	return 0;
+}
+
+int main(void)
+{
+	const int arr[] = { INT_MIN, 0, 1, 2, 3, 4, 5, 6, INT_MAX };
+	unsigned int start, num, i, total = 0;
+	int key;
+
+	plan_tests(285);
+
+	for (start = 0; start < ARRAY_SIZE(arr); start++) {
+		for (num = 0; num < ARRAY_SIZE(arr) - start; num++) {
+			key = 7;
+			ok1(asearch(&key, &arr[start], num, test_cmp) == NULL);
+			total++;
+			for (i = start; i < start+num; i++) {
+				const int *ret;
+				key = arr[i];
+				ret = asearch(&key, &arr[start], num, test_cmp);
+				ok1(ret);
+				ok1(ret && *ret == key);
+				total++;
+			}
+		}
+	}
+	diag("Tested %u searches\n", total);
+	return exit_status();
+}
diff --git a/lib/ccan/build_assert/LICENSE b/lib/ccan/build_assert/LICENSE
new file mode 100644
index 0000000000..5522aa5f33
--- /dev/null
+++ b/lib/ccan/build_assert/LICENSE
@@ -0,0 +1,508 @@
+
+                  GNU LESSER GENERAL PUBLIC LICENSE
+                       Version 2.1, February 1999
+
+ Copyright (C) 1991, 1999 Free Software Foundation, Inc.
+	51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+[This is the first released version of the Lesser GPL.  It also counts
+ as the successor of the GNU Library Public License, version 2, hence
+ the version number 2.1.]
+
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+If any portion of this section is held invalid or unenforceable under
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+
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+integrity of the free software distribution system which is
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+through that system in reliance on consistent application of that
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+to distribute software through any other system and a licensee cannot
+impose that choice.
+
+This section is intended to make thoroughly clear what is believed to
+be a consequence of the rest of this License.
+
+  12. If the distribution and/or use of the Library is restricted in
+certain countries either by patents or by copyrighted interfaces, the
+original copyright holder who places the Library under this License
+may add an explicit geographical distribution limitation excluding those
+countries, so that distribution is permitted only in or among
+countries not thus excluded.  In such case, this License incorporates
+the limitation as if written in the body of this License.
+
+  13. The Free Software Foundation may publish revised and/or new
+versions of the Lesser General Public License from time to time.
+Such new versions will be similar in spirit to the present version,
+but may differ in detail to address new problems or concerns.
+
+Each version is given a distinguishing version number.  If the Library
+specifies a version number of this License which applies to it and
+"any later version", you have the option of following the terms and
+conditions either of that version or of any later version published by
+the Free Software Foundation.  If the Library does not specify a
+license version number, you may choose any version ever published by
+the Free Software Foundation.
+
+  14. If you wish to incorporate parts of the Library into other free
+programs whose distribution conditions are incompatible with these,
+write to the author to ask for permission.  For software which is
+copyrighted by the Free Software Foundation, write to the Free
+Software Foundation; we sometimes make exceptions for this.  Our
+decision will be guided by the two goals of preserving the free status
+of all derivatives of our free software and of promoting the sharing
+and reuse of software generally.
+
+                            NO WARRANTY
+
+  15. BECAUSE THE LIBRARY IS LICENSED FREE OF CHARGE, THERE IS NO
+WARRANTY FOR THE LIBRARY, TO THE EXTENT PERMITTED BY APPLICABLE LAW.
+EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT HOLDERS AND/OR
+OTHER PARTIES PROVIDE THE LIBRARY "AS IS" WITHOUT WARRANTY OF ANY
+KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, THE
+IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
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+LIBRARY IS WITH YOU.  SHOULD THE LIBRARY PROVE DEFECTIVE, YOU ASSUME
+THE COST OF ALL NECESSARY SERVICING, REPAIR OR CORRECTION.
+
+  16. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR AGREED TO IN
+WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MAY MODIFY
+AND/OR REDISTRIBUTE THE LIBRARY AS PERMITTED ABOVE, BE LIABLE TO YOU
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+LIBRARY (INCLUDING BUT NOT LIMITED TO LOSS OF DATA OR DATA BEING
+RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD PARTIES OR A
+FAILURE OF THE LIBRARY TO OPERATE WITH ANY OTHER SOFTWARE), EVEN IF
+SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
+DAMAGES.
+
+                     END OF TERMS AND CONDITIONS
+
+           How to Apply These Terms to Your New Libraries
+
+  If you develop a new library, and you want it to be of the greatest
+possible use to the public, we recommend making it free software that
+everyone can redistribute and change.  You can do so by permitting
+redistribution under these terms (or, alternatively, under the terms
+of the ordinary General Public License).
+
+  To apply these terms, attach the following notices to the library.
+It is safest to attach them to the start of each source file to most
+effectively convey the exclusion of warranty; and each file should
+have at least the "copyright" line and a pointer to where the full
+notice is found.
+
+
+    <one line to give the library's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This library is free software; you can redistribute it and/or
+    modify it under the terms of the GNU Lesser General Public
+    License as published by the Free Software Foundation; either
+    version 2.1 of the License, or (at your option) any later version.
+
+    This library is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+    Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public
+    License along with this library; if not, write to the Free Software
+    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+Also add information on how to contact you by electronic and paper mail.
+
+You should also get your employer (if you work as a programmer) or
+your school, if any, to sign a "copyright disclaimer" for the library,
+if necessary.  Here is a sample; alter the names:
+
+  Yoyodyne, Inc., hereby disclaims all copyright interest in the
+  library `Frob' (a library for tweaking knobs) written by James
+  Random Hacker.
+
+  <signature of Ty Coon>, 1 April 1990
+  Ty Coon, President of Vice
+
+That's all there is to it!
diff --git a/lib/ccan/build_assert/_info b/lib/ccan/build_assert/_info
new file mode 100644
index 0000000000..0906af07e6
--- /dev/null
+++ b/lib/ccan/build_assert/_info
@@ -0,0 +1,49 @@
+#include <stdio.h>
+#include <string.h>
+#include "config.h"
+
+/**
+ * build_assert - routines for build-time assertions
+ *
+ * This code provides routines which will cause compilation to fail should some
+ * assertion be untrue: such failures are preferable to run-time assertions,
+ * but much more limited since they can only depends on compile-time constants.
+ *
+ * These assertions are most useful when two parts of the code must be kept in
+ * sync: it is better to avoid such cases if possible, but seconds best is to
+ * detect invalid changes at build time.
+ *
+ * For example, a tricky piece of code might rely on a certain element being at
+ * the start of the structure.  To ensure that future changes don't break it,
+ * you would catch such changes in your code like so:
+ *
+ * Example:
+ *	#include <stddef.h>
+ *	#include <ccan/build_assert/build_assert.h>
+ *
+ *	struct foo {
+ *		char string[5];
+ *		int x;
+ *	};
+ *
+ *	static char *foo_string(struct foo *foo)
+ *	{
+ *		// This trick requires that the string be first in the structure
+ *		BUILD_ASSERT(offsetof(struct foo, string) == 0);
+ *		return (char *)foo;
+ *	}
+ *
+ * License: LGPL (2 or any later version)
+ * Author: Rusty Russell <rusty@rustcorp.com.au>
+ */
+int main(int argc, char *argv[])
+{
+	if (argc != 2)
+		return 1;
+
+	if (strcmp(argv[1], "depends") == 0)
+		/* Nothing. */
+		return 0;
+
+	return 1;
+}
diff --git a/lib/ccan/build_assert/build_assert.h b/lib/ccan/build_assert/build_assert.h
new file mode 100644
index 0000000000..24e59c44cd
--- /dev/null
+++ b/lib/ccan/build_assert/build_assert.h
@@ -0,0 +1,39 @@
+#ifndef CCAN_BUILD_ASSERT_H
+#define CCAN_BUILD_ASSERT_H
+
+/**
+ * BUILD_ASSERT - assert a build-time dependency.
+ * @cond: the compile-time condition which must be true.
+ *
+ * Your compile will fail if the condition isn't true, or can't be evaluated
+ * by the compiler.  This can only be used within a function.
+ *
+ * Example:
+ *	#include <stddef.h>
+ *	...
+ *	static char *foo_to_char(struct foo *foo)
+ *	{
+ *		// This code needs string to be at start of foo.
+ *		BUILD_ASSERT(offsetof(struct foo, string) == 0);
+ *		return (char *)foo;
+ *	}
+ */
+#define BUILD_ASSERT(cond) \
+	do { (void) sizeof(char [1 - 2*!(cond)]); } while(0)
+
+/**
+ * BUILD_ASSERT_OR_ZERO - assert a build-time dependency, as an expression.
+ * @cond: the compile-time condition which must be true.
+ *
+ * Your compile will fail if the condition isn't true, or can't be evaluated
+ * by the compiler.  This can be used in an expression: its value is "0".
+ *
+ * Example:
+ *	#define foo_to_char(foo)					\
+ *		 ((char *)(foo)						\
+ *		  + BUILD_ASSERT_OR_ZERO(offsetof(struct foo, string) == 0))
+ */
+#define BUILD_ASSERT_OR_ZERO(cond) \
+	(sizeof(char [1 - 2*!(cond)]) - 1)
+
+#endif /* CCAN_BUILD_ASSERT_H */
diff --git a/lib/ccan/build_assert/test/compile_fail-expr.c b/lib/ccan/build_assert/test/compile_fail-expr.c
new file mode 100644
index 0000000000..109215b8aa
--- /dev/null
+++ b/lib/ccan/build_assert/test/compile_fail-expr.c
@@ -0,0 +1,10 @@
+#include <ccan/build_assert/build_assert.h>
+
+int main(int argc, char *argv[])
+{
+#ifdef FAIL
+	return BUILD_ASSERT_OR_ZERO(1 == 0);
+#else
+	return 0;
+#endif
+}
diff --git a/lib/ccan/build_assert/test/compile_fail.c b/lib/ccan/build_assert/test/compile_fail.c
new file mode 100644
index 0000000000..37d95eddc9
--- /dev/null
+++ b/lib/ccan/build_assert/test/compile_fail.c
@@ -0,0 +1,9 @@
+#include <ccan/build_assert/build_assert.h>
+
+int main(int argc, char *argv[])
+{
+#ifdef FAIL
+	BUILD_ASSERT(1 == 0);
+#endif
+	return 0;
+}
diff --git a/lib/ccan/build_assert/test/compile_ok.c b/lib/ccan/build_assert/test/compile_ok.c
new file mode 100644
index 0000000000..4105484d1f
--- /dev/null
+++ b/lib/ccan/build_assert/test/compile_ok.c
@@ -0,0 +1,7 @@
+#include <ccan/build_assert/build_assert.h>
+
+int main(int argc, char *argv[])
+{
+	BUILD_ASSERT(1 == 1);
+	return 0;
+}
diff --git a/lib/ccan/build_assert/test/run-BUILD_ASSERT_OR_ZERO.c b/lib/ccan/build_assert/test/run-BUILD_ASSERT_OR_ZERO.c
new file mode 100644
index 0000000000..4185821331
--- /dev/null
+++ b/lib/ccan/build_assert/test/run-BUILD_ASSERT_OR_ZERO.c
@@ -0,0 +1,9 @@
+#include <ccan/build_assert/build_assert.h>
+#include <ccan/tap/tap.h>
+
+int main(int argc, char *argv[])
+{
+	plan_tests(1);
+	ok1(BUILD_ASSERT_OR_ZERO(1 == 1) == 0);
+	return exit_status();
+}
diff --git a/lib/ccan/build_assert/test/run-EXPR_BUILD_ASSERT.c b/lib/ccan/build_assert/test/run-EXPR_BUILD_ASSERT.c
new file mode 100644
index 0000000000..91bbbbbf75
--- /dev/null
+++ b/lib/ccan/build_assert/test/run-EXPR_BUILD_ASSERT.c
@@ -0,0 +1,9 @@
+#include <ccan/build_assert/build_assert.h>
+#include <ccan/tap/tap.h>
+
+int main(int argc, char *argv[])
+{
+	plan_tests(1);
+	ok1(EXPR_BUILD_ASSERT(1 == 1) == 0);
+	return exit_status();
+}
diff --git a/lib/ccan/cast/LICENSE b/lib/ccan/cast/LICENSE
new file mode 100644
index 0000000000..cca7fc278f
--- /dev/null
+++ b/lib/ccan/cast/LICENSE
@@ -0,0 +1,165 @@
+		   GNU LESSER GENERAL PUBLIC LICENSE
+                       Version 3, 29 June 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+
+  This version of the GNU Lesser General Public License incorporates
+the terms and conditions of version 3 of the GNU General Public
+License, supplemented by the additional permissions listed below.
+
+  0. Additional Definitions.
+
+  As used herein, "this License" refers to version 3 of the GNU Lesser
+General Public License, and the "GNU GPL" refers to version 3 of the GNU
+General Public License.
+
+  "The Library" refers to a covered work governed by this License,
+other than an Application or a Combined Work as defined below.
+
+  An "Application" is any work that makes use of an interface provided
+by the Library, but which is not otherwise based on the Library.
+Defining a subclass of a class defined by the Library is deemed a mode
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+
+  A "Combined Work" is a work produced by combining or linking an
+Application with the Library.  The particular version of the Library
+with which the Combined Work was made is also called the "Linked
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+
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+based on the Application, and not on the Linked Version.
+
+  The "Corresponding Application Code" for a Combined Work means the
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+Application, but excluding the System Libraries of the Combined Work.
+
+  1. Exception to Section 3 of the GNU GPL.
+
+  You may convey a covered work under sections 3 and 4 of this License
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+
+  2. Conveying Modified Versions.
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+
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+
+   b) under the GNU GPL, with none of the additional permissions of
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+
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+
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+(ten or fewer lines in length), you do both of the following:
+
+   a) Give prominent notice with each copy of the object code that the
+   Library is used in it and that the Library and its use are
+   covered by this License.
+
+   b) Accompany the object code with a copy of the GNU GPL and this license
+   document.
+
+  4. Combined Works.
+
+  You may convey a Combined Work under terms of your choice that,
+taken together, effectively do not restrict modification of the
+portions of the Library contained in the Combined Work and reverse
+engineering for debugging such modifications, if you also do each of
+the following:
+
+   a) Give prominent notice with each copy of the Combined Work that
+   the Library is used in it and that the Library and its use are
+   covered by this License.
+
+   b) Accompany the Combined Work with a copy of the GNU GPL and this license
+   document.
+
+   c) For a Combined Work that displays copyright notices during
+   execution, include the copyright notice for the Library among
+   these notices, as well as a reference directing the user to the
+   copies of the GNU GPL and this license document.
+
+   d) Do one of the following:
+
+       0) Convey the Minimal Corresponding Source under the terms of this
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+       suitable for, and under terms that permit, the user to
+       recombine or relink the Application with a modified version of
+       the Linked Version to produce a modified Combined Work, in the
+       manner specified by section 6 of the GNU GPL for conveying
+       Corresponding Source.
+
+       1) Use a suitable shared library mechanism for linking with the
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+       a copy of the Library already present on the user's computer
+       system, and (b) will operate properly with a modified version
+       of the Library that is interface-compatible with the Linked
+       Version.
+
+   e) Provide Installation Information, but only if you would otherwise
+   be required to provide such information under section 6 of the
+   GNU GPL, and only to the extent that such information is
+   necessary to install and execute a modified version of the
+   Combined Work produced by recombining or relinking the
+   Application with a modified version of the Linked Version. (If
+   you use option 4d0, the Installation Information must accompany
+   the Minimal Corresponding Source and Corresponding Application
+   Code. If you use option 4d1, you must provide the Installation
+   Information in the manner specified by section 6 of the GNU GPL
+   for conveying Corresponding Source.)
+
+  5. Combined Libraries.
+
+  You may place library facilities that are a work based on the
+Library side by side in a single library together with other library
+facilities that are not Applications and are not covered by this
+License, and convey such a combined library under terms of your
+choice, if you do both of the following:
+
+   a) Accompany the combined library with a copy of the same work based
+   on the Library, uncombined with any other library facilities,
+   conveyed under the terms of this License.
+
+   b) Give prominent notice with the combined library that part of it
+   is a work based on the Library, and explaining where to find the
+   accompanying uncombined form of the same work.
+
+  6. Revised Versions of the GNU Lesser General Public License.
+
+  The Free Software Foundation may publish revised and/or new versions
+of the GNU Lesser General Public License from time to time. Such new
+versions will be similar in spirit to the present version, but may
+differ in detail to address new problems or concerns.
+
+  Each version is given a distinguishing version number. If the
+Library as you received it specifies that a certain numbered version
+of the GNU Lesser General Public License "or any later version"
+applies to it, you have the option of following the terms and
+conditions either of that published version or of any later version
+published by the Free Software Foundation. If the Library as you
+received it does not specify a version number of the GNU Lesser
+General Public License, you may choose any version of the GNU Lesser
+General Public License ever published by the Free Software Foundation.
+
+  If the Library as you received it specifies that a proxy can decide
+whether future versions of the GNU Lesser General Public License shall
+apply, that proxy's public statement of acceptance of any version is
+permanent authorization for you to choose that version for the
+Library.
diff --git a/lib/ccan/cast/_info b/lib/ccan/cast/_info
new file mode 100644
index 0000000000..5f82a05b8f
--- /dev/null
+++ b/lib/ccan/cast/_info
@@ -0,0 +1,84 @@
+#include <string.h>
+#include "config.h"
+
+/**
+ * cast - routines for safer casting.
+ *
+ * Often you want to cast in a limited way, such as removing a const or
+ * switching between integer types.  However, normal casts will work on
+ * almost any type, making them dangerous when the code changes.
+ *
+ * These C++-inspired macros serve two purposes: they make it clear the
+ * exact reason for the cast, and they also (with some compilers) cause
+ * errors when misused.
+ *
+ * Based on Jan Engelhardt's libHX macros: http://libhx.sourceforge.net/
+ *
+ * Author: Jan Engelhardt
+ * Maintainer: Rusty Russell <rusty@rustcorp.com.au>
+ * License: LGPL
+ *
+ * Example:
+ *	// Given "test" contains "3 t's in 'test string'
+ *	#include <ccan/cast/cast.h>
+ *	#include <stdint.h>
+ *	#include <stdio.h>
+ *
+ *	// Find char @orig in @str, if @repl, replace them.  Return number.
+ *	static size_t find_chars(char *str, char orig, char repl)
+ *	{
+ *		size_t i, count = 0;
+ *		for (i = 0; str[i]; i++) {
+ *			if (str[i] == orig) {
+ *				count++;
+ *				if (repl)
+ *					str[i] = repl;
+ *			}
+ *		}
+ *		return count;
+ *	}
+ *
+ *	// Terrible hash function.
+ *	static uint64_t hash_string(const unsigned char *str)
+ *	{
+ *		size_t i;
+ *		uint64_t hash = 0;
+ *		for (i = 0; str[i]; i++)
+ *			hash += str[i];
+ *		return hash;
+ *	}
+ *
+ *	int main(int argc, char *argv[])
+ *	{
+ *		uint64_t hash;
+ *
+ *		// find_chars wants a non-const string, but doesn't
+ *		// need it if repl == 0.
+ *		printf("%zu %c's in 'test string'\n",
+ *		       find_chars(cast_const(char *, "test string"),
+ *				  argv[1][0], 0),
+ *		       argv[1][0]);
+ *
+ *		// hash_string wants an unsigned char.
+ *		hash = hash_string(cast_signed(unsigned char *, argv[1]));
+ *
+ *		// Need a long long to hand to printf.
+ *		printf("Hash of '%s' = %llu\n", argv[1],
+ *		       cast_static(unsigned long long, hash));
+ *		return 0;
+ *	}
+ *
+ */
+int main(int argc, char *argv[])
+{
+	/* Expect exactly one argument */
+	if (argc != 2)
+		return 1;
+
+	if (strcmp(argv[1], "depends") == 0) {
+		printf("ccan/build_assert\n");
+		return 0;
+	}
+
+	return 1;
+}
diff --git a/lib/ccan/cast/cast.h b/lib/ccan/cast/cast.h
new file mode 100644
index 0000000000..daebd85723
--- /dev/null
+++ b/lib/ccan/cast/cast.h
@@ -0,0 +1,129 @@
+#ifndef CCAN_CAST_H
+#define CCAN_CAST_H
+#include "config.h"
+#include <stdint.h>
+#include <ccan/build_assert/build_assert.h>
+
+/**
+ * cast_signed - cast a (const) char * to/from (const) signed/unsigned char *.
+ * @type: some char * variant.
+ * @expr: expression (of some char * variant) to cast.
+ *
+ * Some libraries insist on an unsigned char in various places; cast_signed
+ * makes sure (with suitable compiler) that the expression you are casting
+ * only differs in signed/unsigned, not in type or const-ness.
+ */
+#define cast_signed(type, expr)						\
+	((type)(expr)							\
+	 + BUILD_ASSERT_OR_ZERO(cast_sign_compatible(type, (expr))))
+
+/**
+ * cast_const - remove a const qualifier from a pointer.
+ * @type: some pointer type.
+ * @expr: expression to cast.
+ *
+ * This ensures that you are only removing the const qualifier from an
+ * expression.  The expression must otherwise match @type.
+ *
+ * If @type is a pointer to a pointer, you must use cast_const2 (etc).
+ *
+ * Example:
+ *	// Dumb open-coded strstr variant.
+ *	static char *find_needle(const char *haystack)
+ *	{
+ *		size_t i;
+ *		for (i = 0; i < strlen(haystack); i++)
+ *		if (memcmp("needle", haystack+i, strlen("needle")) == 0)
+ *			return cast_const(char *, haystack+i);
+ *		return NULL;
+ *	}
+ */
+#define cast_const(type, expr)						\
+	((type)((intptr_t)(expr)					\
+		+ BUILD_ASSERT_OR_ZERO(cast_const_compat1((expr), type))))
+
+/**
+ * cast_const2 - remove a const qualifier from a pointer to a pointer.
+ * @type: some pointer to pointer type.
+ * @expr: expression to cast.
+ *
+ * This ensures that you are only removing the const qualifier from an
+ * expression.  The expression must otherwise match @type.
+ */
+#define cast_const2(type, expr)						\
+	((type)((intptr_t)(expr)					\
+		+ BUILD_ASSERT_OR_ZERO(cast_const_compat2((expr), type))))
+
+/**
+ * cast_const3 - remove a const from a pointer to a pointer to a pointer..
+ * @type: some pointer to pointer to pointer type.
+ * @expr: expression to cast.
+ *
+ * This ensures that you are only removing the const qualifier from an
+ * expression.  The expression must otherwise match @type.
+ */
+#define cast_const3(type, expr)						\
+	((type)((intptr_t)(expr)					\
+		+ BUILD_ASSERT_OR_ZERO(cast_const_compat3((expr), type))))
+
+
+/**
+ * cast_static - explicit mimic of implicit cast.
+ * @type: some type.
+ * @expr: expression to cast.
+ *
+ * This ensures that the cast is not to or from a pointer: it can only be
+ * an implicit cast, such as a pointer to a similar const pointer, or between
+ * integral types.
+ */
+#if HAVE_COMPOUND_LITERALS
+#define cast_static(type, expr)			\
+	((struct { type x; }){(expr)}.x)
+#else
+#define cast_static(type, expr)			\
+	((type)(expr))
+#endif
+
+/* Herein lies the gcc magic to evoke compile errors. */
+#if HAVE_BUILTIN_CHOOSE_EXPR && HAVE_BUILTIN_TYPES_COMPATIBLE_P && HAVE_TYPEOF
+#define cast_sign_compatible(t, e) \
+  __builtin_choose_expr(						\
+	  __builtin_types_compatible_p(__typeof__(t), char *) ||	\
+	  __builtin_types_compatible_p(__typeof__(t), signed char *) || \
+	  __builtin_types_compatible_p(__typeof__(t), unsigned char *), \
+	  /* if type is not const qualified */				\
+	  __builtin_types_compatible_p(__typeof__(e), char *) ||	\
+	  __builtin_types_compatible_p(__typeof__(e), signed char *) || \
+	  __builtin_types_compatible_p(__typeof__(e), unsigned char *), \
+	  /* and if it is... */						\
+	  __builtin_types_compatible_p(__typeof__(e), const char *) ||	\
+	  __builtin_types_compatible_p(__typeof__(e), const signed char *) || \
+	  __builtin_types_compatible_p(__typeof__(e), const unsigned char *) ||\
+	  __builtin_types_compatible_p(__typeof__(e), char *) ||	\
+	  __builtin_types_compatible_p(__typeof__(e), signed char *) ||	\
+	  __builtin_types_compatible_p(__typeof__(e), unsigned char *)	\
+	  )
+
+#define cast_const_strip1(expr)			\
+	__typeof__(*(struct { int z; __typeof__(expr) x; }){0}.x)
+#define cast_const_strip2(expr) \
+	__typeof__(**(struct { int z; __typeof__(expr) x; }){0}.x)
+#define cast_const_strip3(expr) \
+	__typeof__(***(struct { int z; __typeof__(expr) x; }){0}.x)
+#define cast_const_compat1(expr, type)					\
+	__builtin_types_compatible_p(cast_const_strip1(expr),		\
+				     cast_const_strip1(type))
+#define cast_const_compat2(expr, type)					\
+	__builtin_types_compatible_p(cast_const_strip2(expr),		\
+				     cast_const_strip2(type))
+#define cast_const_compat3(expr, type)					\
+	__builtin_types_compatible_p(cast_const_strip3(expr),		\
+				     cast_const_strip3(type))
+#else
+#define cast_sign_compatible(type, expr)		\
+	(sizeof(*(type)0) == 1 && sizeof(*(expr)) == 1)
+#define cast_const_compat1(expr, type)		(1)
+#define cast_const_compat2(expr, type)		(1)
+#define cast_const_compat3(expr, type)		(1)
+#endif
+#endif /* CCAN_CAST_H */
diff --git a/lib/ccan/cast/test/compile_fail-cast_const.c b/lib/ccan/cast/test/compile_fail-cast_const.c
new file mode 100644
index 0000000000..277f3de1c4
--- /dev/null
+++ b/lib/ccan/cast/test/compile_fail-cast_const.c
@@ -0,0 +1,29 @@
+#include <ccan/cast/cast.h>
+#include <stdlib.h>
+
+/* Note: this *isn't* sizeof(char) on all platforms. */
+struct char_struct {
+	char c;
+};
+
+int main(int argc, char *argv[])
+{
+	char *uc;
+	const
+#ifdef FAIL
+		struct char_struct
+#else
+		char
+#endif
+		*p = NULL;
+
+	uc = cast_const(char *, p);
+	(void) uc; /* Suppress unused-but-set-variable warning. */
+	return 0;
+}
+
+#ifdef FAIL
+#if !HAVE_TYPEOF||!HAVE_BUILTIN_CHOOSE_EXPR||!HAVE_BUILTIN_TYPES_COMPATIBLE_P
+#error "Unfortunately we don't fail if cast_const can only use size"
+#endif
+#endif
diff --git a/lib/ccan/cast/test/compile_fail-cast_const2.c b/lib/ccan/cast/test/compile_fail-cast_const2.c
new file mode 100644
index 0000000000..e671e88eda
--- /dev/null
+++ b/lib/ccan/cast/test/compile_fail-cast_const2.c
@@ -0,0 +1,29 @@
+#include <ccan/cast/cast.h>
+#include <stdlib.h>
+
+/* Note: this *isn't* sizeof(char) on all platforms. */
+struct char_struct {
+	char c;
+};
+
+int main(int argc, char *argv[])
+{
+	char **uc;
+	const
+#ifdef FAIL
+		struct char_struct
+#else
+		char
+#endif
+		**p = NULL;
+
+	uc = cast_const2(char **, p);
+	(void) uc; /* Suppress unused-but-set-variable warning. */
+	return 0;
+}
+
+#ifdef FAIL
+#if !HAVE_TYPEOF||!HAVE_BUILTIN_CHOOSE_EXPR||!HAVE_BUILTIN_TYPES_COMPATIBLE_P
+#error "Unfortunately we don't fail if cast_const can only use size"
+#endif
+#endif
diff --git a/lib/ccan/cast/test/compile_fail-cast_const3.c b/lib/ccan/cast/test/compile_fail-cast_const3.c
new file mode 100644
index 0000000000..e958e2dde5
--- /dev/null
+++ b/lib/ccan/cast/test/compile_fail-cast_const3.c
@@ -0,0 +1,29 @@
+#include <ccan/cast/cast.h>
+#include <stdlib.h>
+
+/* Note: this *isn't* sizeof(char) on all platforms. */
+struct char_struct {
+	char c;
+};
+
+int main(int argc, char *argv[])
+{
+	char ***uc;
+	const
+#ifdef FAIL
+		struct char_struct
+#else
+		char
+#endif
+		***p = NULL;
+
+	uc = cast_const3(char ***, p);
+	(void) uc; /* Suppress unused-but-set-variable warning. */
+	return 0;
+}
+
+#ifdef FAIL
+#if !HAVE_TYPEOF||!HAVE_BUILTIN_CHOOSE_EXPR||!HAVE_BUILTIN_TYPES_COMPATIBLE_P
+#error "Unfortunately we don't fail if cast_const can only use size"
+#endif
+#endif
diff --git a/lib/ccan/cast/test/compile_fail-cast_signed-const.c b/lib/ccan/cast/test/compile_fail-cast_signed-const.c
new file mode 100644
index 0000000000..9971dc8eb3
--- /dev/null
+++ b/lib/ccan/cast/test/compile_fail-cast_signed-const.c
@@ -0,0 +1,22 @@
+#include <ccan/cast/cast.h>
+#include <stdlib.h>
+
+int main(int argc, char *argv[])
+{
+	unsigned char *uc;
+#ifdef FAIL
+	const
+#endif
+	char
+		*p = NULL;
+
+	uc = cast_signed(unsigned char *, p);
+	(void) uc; /* Suppress unused-but-set-variable warning. */
+	return 0;
+}
+
+#ifdef FAIL
+#if !HAVE_TYPEOF||!HAVE_BUILTIN_CHOOSE_EXPR||!HAVE_BUILTIN_TYPES_COMPATIBLE_P
+#error "Unfortunately we don't fail if cast_const can only use size"
+#endif
+#endif
diff --git a/lib/ccan/cast/test/compile_fail-cast_signed-sizesame.c b/lib/ccan/cast/test/compile_fail-cast_signed-sizesame.c
new file mode 100644
index 0000000000..2bc40b2f46
--- /dev/null
+++ b/lib/ccan/cast/test/compile_fail-cast_signed-sizesame.c
@@ -0,0 +1,29 @@
+#include <ccan/cast/cast.h>
+#include <stdlib.h>
+
+/* Note: this *isn't* sizeof(char) on all platforms. */
+struct char_struct {
+	char c;
+};
+
+int main(int argc, char *argv[])
+{
+	unsigned char *uc;
+#ifdef FAIL
+	struct char_struct
+#else
+	char
+#endif
+		*p = NULL;
+
+	uc = cast_signed(unsigned char *, p);
+
+	(void) uc; /* Suppress unused-but-set-variable warning. */
+	return 0;
+}
+
+#ifdef FAIL
+#if !HAVE_TYPEOF||!HAVE_BUILTIN_CHOOSE_EXPR||!HAVE_BUILTIN_TYPES_COMPATIBLE_P
+#error "Unfortunately we don't fail if cast_signed can only use size"
+#endif
+#endif
diff --git a/lib/ccan/cast/test/compile_fail-cast_signed.c b/lib/ccan/cast/test/compile_fail-cast_signed.c
new file mode 100644
index 0000000000..66bcc0a1b5
--- /dev/null
+++ b/lib/ccan/cast/test/compile_fail-cast_signed.c
@@ -0,0 +1,17 @@
+#include <ccan/cast/cast.h>
+#include <stdlib.h>
+
+int main(int argc, char *argv[])
+{
+	unsigned char *uc;
+#ifdef FAIL
+	int
+#else
+	char
+#endif
+		*p = NULL;
+
+	uc = cast_signed(unsigned char *, p);
+	(void) uc; /* Suppress unused-but-set-variable warning. */
+	return 0;
+}
diff --git a/lib/ccan/cast/test/compile_fail-cast_static-2.c b/lib/ccan/cast/test/compile_fail-cast_static-2.c
new file mode 100644
index 0000000000..8a12025384
--- /dev/null
+++ b/lib/ccan/cast/test/compile_fail-cast_static-2.c
@@ -0,0 +1,23 @@
+#include <ccan/cast/cast.h>
+#include <stdlib.h>
+
+int main(int argc, char *argv[])
+{
+	char *c;
+#ifdef FAIL
+	long
+#else
+	char
+#endif
+		*p = 0;
+
+	c = cast_static(char *, p);
+	(void) c; /* Suppress unused-but-set-variable warning. */
+	return 0;
+}
+
+#ifdef FAIL
+#if !HAVE_COMPOUND_LITERALS
+#error "Unfortunately we don't fail if cast_static is a noop"
+#endif
+#endif
diff --git a/lib/ccan/cast/test/compile_fail-cast_static-3.c b/lib/ccan/cast/test/compile_fail-cast_static-3.c
new file mode 100644
index 0000000000..6296b75276
--- /dev/null
+++ b/lib/ccan/cast/test/compile_fail-cast_static-3.c
@@ -0,0 +1,21 @@
+#include <ccan/cast/cast.h>
+#include <stdlib.h>
+
+int main(int argc, char *argv[])
+{
+	char *c;
+#ifdef FAIL
+	const
+#endif
+		char *p = 0;
+
+	c = cast_static(char *, p);
+	(void) c; /* Suppress unused-but-set-variable warning. */
+	return 0;
+}
+
+#ifdef FAIL
+#if !HAVE_COMPOUND_LITERALS
+#error "Unfortunately we don't fail if cast_static is a noop"
+#endif
+#endif
diff --git a/lib/ccan/cast/test/compile_fail-cast_static.c b/lib/ccan/cast/test/compile_fail-cast_static.c
new file mode 100644
index 0000000000..0f9e478047
--- /dev/null
+++ b/lib/ccan/cast/test/compile_fail-cast_static.c
@@ -0,0 +1,17 @@
+#include <ccan/cast/cast.h>
+#include <stdlib.h>
+
+int main(int argc, char *argv[])
+{
+	char c;
+#ifdef FAIL
+	char *
+#else
+	long
+#endif
+		x = 0;
+
+	c = cast_static(char, x);
+	(void) c; /* Suppress unused-but-set-variable warning. */
+	return 0;
+}
diff --git a/lib/ccan/cast/test/compile_ok-cast_void.c b/lib/ccan/cast/test/compile_ok-cast_void.c
new file mode 100644
index 0000000000..c649d283b3
--- /dev/null
+++ b/lib/ccan/cast/test/compile_ok-cast_void.c
@@ -0,0 +1,12 @@
+#include <ccan/cast/cast.h>
+
+static void *remove_void(const void *p)
+{
+	return cast_const(void *, p);
+}
+
+int main(void)
+{
+	void *p = remove_void("foo");
+	return !p;
+}
diff --git a/lib/ccan/compiler/LICENSE b/lib/ccan/compiler/LICENSE
new file mode 100644
index 0000000000..cca7fc278f
--- /dev/null
+++ b/lib/ccan/compiler/LICENSE
@@ -0,0 +1,165 @@
+		   GNU LESSER GENERAL PUBLIC LICENSE
+                       Version 3, 29 June 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+
+  This version of the GNU Lesser General Public License incorporates
+the terms and conditions of version 3 of the GNU General Public
+License, supplemented by the additional permissions listed below.
+
+  0. Additional Definitions.
+
+  As used herein, "this License" refers to version 3 of the GNU Lesser
+General Public License, and the "GNU GPL" refers to version 3 of the GNU
+General Public License.
+
+  "The Library" refers to a covered work governed by this License,
+other than an Application or a Combined Work as defined below.
+
+  An "Application" is any work that makes use of an interface provided
+by the Library, but which is not otherwise based on the Library.
+Defining a subclass of a class defined by the Library is deemed a mode
+of using an interface provided by the Library.
+
+  A "Combined Work" is a work produced by combining or linking an
+Application with the Library.  The particular version of the Library
+with which the Combined Work was made is also called the "Linked
+Version".
+
+  The "Minimal Corresponding Source" for a Combined Work means the
+Corresponding Source for the Combined Work, excluding any source code
+for portions of the Combined Work that, considered in isolation, are
+based on the Application, and not on the Linked Version.
+
+  The "Corresponding Application Code" for a Combined Work means the
+object code and/or source code for the Application, including any data
+and utility programs needed for reproducing the Combined Work from the
+Application, but excluding the System Libraries of the Combined Work.
+
+  1. Exception to Section 3 of the GNU GPL.
+
+  You may convey a covered work under sections 3 and 4 of this License
+without being bound by section 3 of the GNU GPL.
+
+  2. Conveying Modified Versions.
+
+  If you modify a copy of the Library, and, in your modifications, a
+facility refers to a function or data to be supplied by an Application
+that uses the facility (other than as an argument passed when the
+facility is invoked), then you may convey a copy of the modified
+version:
+
+   a) under this License, provided that you make a good faith effort to
+   ensure that, in the event an Application does not supply the
+   function or data, the facility still operates, and performs
+   whatever part of its purpose remains meaningful, or
+
+   b) under the GNU GPL, with none of the additional permissions of
+   this License applicable to that copy.
+
+  3. Object Code Incorporating Material from Library Header Files.
+
+  The object code form of an Application may incorporate material from
+a header file that is part of the Library.  You may convey such object
+code under terms of your choice, provided that, if the incorporated
+material is not limited to numerical parameters, data structure
+layouts and accessors, or small macros, inline functions and templates
+(ten or fewer lines in length), you do both of the following:
+
+   a) Give prominent notice with each copy of the object code that the
+   Library is used in it and that the Library and its use are
+   covered by this License.
+
+   b) Accompany the object code with a copy of the GNU GPL and this license
+   document.
+
+  4. Combined Works.
+
+  You may convey a Combined Work under terms of your choice that,
+taken together, effectively do not restrict modification of the
+portions of the Library contained in the Combined Work and reverse
+engineering for debugging such modifications, if you also do each of
+the following:
+
+   a) Give prominent notice with each copy of the Combined Work that
+   the Library is used in it and that the Library and its use are
+   covered by this License.
+
+   b) Accompany the Combined Work with a copy of the GNU GPL and this license
+   document.
+
+   c) For a Combined Work that displays copyright notices during
+   execution, include the copyright notice for the Library among
+   these notices, as well as a reference directing the user to the
+   copies of the GNU GPL and this license document.
+
+   d) Do one of the following:
+
+       0) Convey the Minimal Corresponding Source under the terms of this
+       License, and the Corresponding Application Code in a form
+       suitable for, and under terms that permit, the user to
+       recombine or relink the Application with a modified version of
+       the Linked Version to produce a modified Combined Work, in the
+       manner specified by section 6 of the GNU GPL for conveying
+       Corresponding Source.
+
+       1) Use a suitable shared library mechanism for linking with the
+       Library.  A suitable mechanism is one that (a) uses at run time
+       a copy of the Library already present on the user's computer
+       system, and (b) will operate properly with a modified version
+       of the Library that is interface-compatible with the Linked
+       Version.
+
+   e) Provide Installation Information, but only if you would otherwise
+   be required to provide such information under section 6 of the
+   GNU GPL, and only to the extent that such information is
+   necessary to install and execute a modified version of the
+   Combined Work produced by recombining or relinking the
+   Application with a modified version of the Linked Version. (If
+   you use option 4d0, the Installation Information must accompany
+   the Minimal Corresponding Source and Corresponding Application
+   Code. If you use option 4d1, you must provide the Installation
+   Information in the manner specified by section 6 of the GNU GPL
+   for conveying Corresponding Source.)
+
+  5. Combined Libraries.
+
+  You may place library facilities that are a work based on the
+Library side by side in a single library together with other library
+facilities that are not Applications and are not covered by this
+License, and convey such a combined library under terms of your
+choice, if you do both of the following:
+
+   a) Accompany the combined library with a copy of the same work based
+   on the Library, uncombined with any other library facilities,
+   conveyed under the terms of this License.
+
+   b) Give prominent notice with the combined library that part of it
+   is a work based on the Library, and explaining where to find the
+   accompanying uncombined form of the same work.
+
+  6. Revised Versions of the GNU Lesser General Public License.
+
+  The Free Software Foundation may publish revised and/or new versions
+of the GNU Lesser General Public License from time to time. Such new
+versions will be similar in spirit to the present version, but may
+differ in detail to address new problems or concerns.
+
+  Each version is given a distinguishing version number. If the
+Library as you received it specifies that a certain numbered version
+of the GNU Lesser General Public License "or any later version"
+applies to it, you have the option of following the terms and
+conditions either of that published version or of any later version
+published by the Free Software Foundation. If the Library as you
+received it does not specify a version number of the GNU Lesser
+General Public License, you may choose any version of the GNU Lesser
+General Public License ever published by the Free Software Foundation.
+
+  If the Library as you received it specifies that a proxy can decide
+whether future versions of the GNU Lesser General Public License shall
+apply, that proxy's public statement of acceptance of any version is
+permanent authorization for you to choose that version for the
+Library.
diff --git a/lib/ccan/compiler/_info b/lib/ccan/compiler/_info
new file mode 100644
index 0000000000..c55ba22f08
--- /dev/null
+++ b/lib/ccan/compiler/_info
@@ -0,0 +1,64 @@
+#include <string.h>
+#include <stdio.h>
+#include "config.h"
+
+/**
+ * compiler - macros for common compiler extensions
+ *
+ * Abstracts away some compiler hints.  Currently these include:
+ * - COLD
+ *	For functions not called in fast paths (aka. cold functions)
+ * - PRINTF_FMT
+ *	For functions which take printf-style parameters.
+ * - IDEMPOTENT
+ *	For functions which return the same value for same parameters.
+ * - NEEDED
+ *	For functions and variables which must be emitted even if unused.
+ * - UNNEEDED
+ *	For functions and variables which need not be emitted if unused.
+ * - UNUSED
+ *	For parameters which are not used.
+ * - IS_COMPILE_CONSTANT
+ *	For using different tradeoffs for compiletime vs runtime evaluation.
+ *
+ * License: LGPL (3 or any later version)
+ * Author: Rusty Russell <rusty@rustcorp.com.au>
+ *
+ * Example:
+ *	#include <ccan/compiler/compiler.h>
+ *	#include <stdio.h>
+ *	#include <stdarg.h>
+ *
+ *	// Example of a (slow-path) logging function.
+ *	static int log_threshold = 2;
+ *	static void COLD PRINTF_FMT(2,3)
+ *		logger(int level, const char *fmt, ...)
+ *	{
+ *		va_list ap;
+ *		va_start(ap, fmt);
+ *		if (level >= log_threshold)
+ *			vfprintf(stderr, fmt, ap);
+ *		va_end(ap);
+ *	}
+ *
+ *	int main(int argc, char *argv[])
+ *	{
+ *		if (argc != 1) {
+ *			logger(3, "Don't want %i arguments!\n", argc-1);
+ *			return 1;
+ *		}
+ *		return 0;
+ *	}
+ */
+int main(int argc, char *argv[])
+{
+	/* Expect exactly one argument */
+	if (argc != 2)
+		return 1;
+
+	if (strcmp(argv[1], "depends") == 0) {
+		return 0;
+	}
+
+	return 1;
+}
diff --git a/lib/ccan/compiler/compiler.h b/lib/ccan/compiler/compiler.h
new file mode 100644
index 0000000000..74e0f1835c
--- /dev/null
+++ b/lib/ccan/compiler/compiler.h
@@ -0,0 +1,216 @@
+#ifndef CCAN_COMPILER_H
+#define CCAN_COMPILER_H
+#include "config.h"
+
+#ifndef COLD
+#if HAVE_ATTRIBUTE_COLD
+/**
+ * COLD - a function is unlikely to be called.
+ *
+ * Used to mark an unlikely code path and optimize appropriately.
+ * It is usually used on logging or error routines.
+ *
+ * Example:
+ * static void COLD moan(const char *reason)
+ * {
+ *	fprintf(stderr, "Error: %s (%s)\n", reason, strerror(errno));
+ * }
+ */
+#define COLD __attribute__((cold))
+#else
+#define COLD
+#endif
+#endif
+
+#ifndef NORETURN
+#if HAVE_ATTRIBUTE_NORETURN
+/**
+ * NORETURN - a function does not return
+ *
+ * Used to mark a function which exits; useful for suppressing warnings.
+ *
+ * Example:
+ * static void NORETURN fail(const char *reason)
+ * {
+ *	fprintf(stderr, "Error: %s (%s)\n", reason, strerror(errno));
+ *	exit(1);
+ * }
+ */
+#define NORETURN __attribute__((noreturn))
+#else
+#define NORETURN
+#endif
+#endif
+
+#ifndef PRINTF_FMT
+#if HAVE_ATTRIBUTE_PRINTF
+/**
+ * PRINTF_FMT - a function takes printf-style arguments
+ * @nfmt: the 1-based number of the function's format argument.
+ * @narg: the 1-based number of the function's first variable argument.
+ *
+ * This allows the compiler to check your parameters as it does for printf().
+ *
+ * Example:
+ * void PRINTF_FMT(2,3) my_printf(const char *prefix, const char *fmt, ...);
+ */
+#define PRINTF_FMT(nfmt, narg) \
+	__attribute__((format(__printf__, nfmt, narg)))
+#else
+#define PRINTF_FMT(nfmt, narg)
+#endif
+#endif
+
+#ifndef IDEMPOTENT
+#if HAVE_ATTRIBUTE_CONST
+/**
+ * IDEMPOTENT - a function's return depends only on its argument
+ *
+ * This allows the compiler to assume that the function will return the exact
+ * same value for the exact same arguments.  This implies that the function
+ * must not use global variables, or dereference pointer arguments.
+ */
+#define IDEMPOTENT __attribute__((const))
+#else
+#define IDEMPOTENT
+#endif
+#endif
+
+#if HAVE_ATTRIBUTE_UNUSED
+#ifndef UNNEEDED
+/**
+ * UNNEEDED - a variable/function may not be needed
+ *
+ * This suppresses warnings about unused variables or functions, but tells
+ * the compiler that if it is unused it need not emit it into the source code.
+ *
+ * Example:
+ * // With some preprocessor options, this is unnecessary.
+ * static UNNEEDED int counter;
+ *
+ * // With some preprocessor options, this is unnecessary.
+ * static UNNEEDED void add_to_counter(int add)
+ * {
+ *	counter += add;
+ * }
+ */
+#define UNNEEDED __attribute__((unused))
+#endif
+
+#ifndef NEEDED
+#if HAVE_ATTRIBUTE_USED
+/**
+ * NEEDED - a variable/function is needed
+ *
+ * This suppresses warnings about unused variables or functions, but tells
+ * the compiler that it must exist even if it (seems) unused.
+ *
+ * Example:
+ *	// Even if this is unused, these are vital for debugging.
+ *	static NEEDED int counter;
+ *	static NEEDED void dump_counter(void)
+ *	{
+ *		printf("Counter is %i\n", counter);
+ *	}
+ */
+#define NEEDED __attribute__((used))
+#else
+/* Before used, unused functions and vars were always emitted. */
+#define NEEDED __attribute__((unused))
+#endif
+#endif
+
+#ifndef UNUSED
+/**
+ * UNUSED - a parameter is unused
+ *
+ * Some compilers (eg. gcc with -W or -Wunused) warn about unused
+ * function parameters.  This suppresses such warnings and indicates
+ * to the reader that it's deliberate.
+ *
+ * Example:
+ *	// This is used as a callback, so needs to have this prototype.
+ *	static int some_callback(void *unused UNUSED)
+ *	{
+ *		return 0;
+ *	}
+ */
+#define UNUSED __attribute__((unused))
+#endif
+#else
+#ifndef UNNEEDED
+#define UNNEEDED
+#endif
+#ifndef NEEDED
+#define NEEDED
+#endif
+#ifndef UNUSED
+#define UNUSED
+#endif
+#endif
+
+#ifndef IS_COMPILE_CONSTANT
+#if HAVE_BUILTIN_CONSTANT_P
+/**
+ * IS_COMPILE_CONSTANT - does the compiler know the value of this expression?
+ * @expr: the expression to evaluate
+ *
+ * When an expression manipulation is complicated, it is usually better to
+ * implement it in a function.  However, if the expression being manipulated is
+ * known at compile time, it is better to have the compiler see the entire
+ * expression so it can simply substitute the result.
+ *
+ * This can be done using the IS_COMPILE_CONSTANT() macro.
+ *
+ * Example:
+ *	enum greek { ALPHA, BETA, GAMMA, DELTA, EPSILON };
+ *
+ *	// Out-of-line version.
+ *	const char *greek_name(enum greek greek);
+ *
+ *	// Inline version.
+ *	static inline const char *_greek_name(enum greek greek)
+ *	{
+ *		switch (greek) {
+ *		case ALPHA: return "alpha";
+ *		case BETA: return "beta";
+ *		case GAMMA: return "gamma";
+ *		case DELTA: return "delta";
+ *		case EPSILON: return "epsilon";
+ *		default: return "**INVALID**";
+ *		}
+ *	}
+ *
+ *	// Use inline if compiler knows answer.  Otherwise call function
+ *	// to avoid copies of the same code everywhere.
+ *	#define greek_name(g)						\
+ *		 (IS_COMPILE_CONSTANT(greek) ? _greek_name(g) : greek_name(g))
+ */
+#define IS_COMPILE_CONSTANT(expr) __builtin_constant_p(expr)
+#else
+/* If we don't know, assume it's not. */
+#define IS_COMPILE_CONSTANT(expr) 0
+#endif
+#endif
+
+#ifndef WARN_UNUSED_RESULT
+#if HAVE_WARN_UNUSED_RESULT
+/**
+ * WARN_UNUSED_RESULT - warn if a function return value is unused.
+ *
+ * Used to mark a function where it is extremely unlikely that the caller
+ * can ignore the result, eg realloc().
+ *
+ * Example:
+ * // buf param may be freed by this; need return value!
+ * static char *WARN_UNUSED_RESULT enlarge(char *buf, unsigned *size)
+ * {
+ *	return realloc(buf, (*size) *= 2);
+ * }
+ */
+#define WARN_UNUSED_RESULT __attribute__((warn_unused_result))
+#else
+#define WARN_UNUSED_RESULT
+#endif
+#endif
+#endif /* CCAN_COMPILER_H */
diff --git a/lib/ccan/compiler/test/compile_fail-printf.c b/lib/ccan/compiler/test/compile_fail-printf.c
new file mode 100644
index 0000000000..8f34ae5a12
--- /dev/null
+++ b/lib/ccan/compiler/test/compile_fail-printf.c
@@ -0,0 +1,22 @@
+#include <ccan/compiler/compiler.h>
+
+static void PRINTF_FMT(2,3) my_printf(int x, const char *fmt, ...)
+{
+}
+
+int main(int argc, char *argv[])
+{
+	unsigned int i = 0;
+
+	my_printf(1, "Not a pointer "
+#ifdef FAIL
+		  "%p",
+#if !HAVE_ATTRIBUTE_PRINTF
+#error "Unfortunately we don't fail if !HAVE_ATTRIBUTE_PRINTF."
+#endif
+#else
+		  "%i",
+#endif
+		  i);
+	return 0;
+}
diff --git a/lib/ccan/compiler/test/run-is_compile_constant.c b/lib/ccan/compiler/test/run-is_compile_constant.c
new file mode 100644
index 0000000000..a66f2e13e6
--- /dev/null
+++ b/lib/ccan/compiler/test/run-is_compile_constant.c
@@ -0,0 +1,15 @@
+#include <ccan/compiler/compiler.h>
+#include <ccan/tap/tap.h>
+
+int main(int argc, char *argv[])
+{
+	plan_tests(2);
+
+	ok1(!IS_COMPILE_CONSTANT(argc));
+#if HAVE_BUILTIN_CONSTANT_P
+	ok1(IS_COMPILE_CONSTANT(7));
+#else
+	pass("If !HAVE_BUILTIN_CONSTANT_P, IS_COMPILE_CONSTANT always false");
+#endif
+	return exit_status();
+}
diff --git a/lib/ccan/endian/LICENSE b/lib/ccan/endian/LICENSE
new file mode 100644
index 0000000000..5522aa5f33
--- /dev/null
+++ b/lib/ccan/endian/LICENSE
@@ -0,0 +1,508 @@
+
+                  GNU LESSER GENERAL PUBLIC LICENSE
+                       Version 2.1, February 1999
+
+ Copyright (C) 1991, 1999 Free Software Foundation, Inc.
+	51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+[This is the first released version of the Lesser GPL.  It also counts
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+ the version number 2.1.]
+
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+  To apply these terms, attach the following notices to the library.
+It is safest to attach them to the start of each source file to most
+effectively convey the exclusion of warranty; and each file should
+have at least the "copyright" line and a pointer to where the full
+notice is found.
+
+
+    <one line to give the library's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This library is free software; you can redistribute it and/or
+    modify it under the terms of the GNU Lesser General Public
+    License as published by the Free Software Foundation; either
+    version 2.1 of the License, or (at your option) any later version.
+
+    This library is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+    Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public
+    License along with this library; if not, write to the Free Software
+    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+Also add information on how to contact you by electronic and paper mail.
+
+You should also get your employer (if you work as a programmer) or
+your school, if any, to sign a "copyright disclaimer" for the library,
+if necessary.  Here is a sample; alter the names:
+
+  Yoyodyne, Inc., hereby disclaims all copyright interest in the
+  library `Frob' (a library for tweaking knobs) written by James
+  Random Hacker.
+
+  <signature of Ty Coon>, 1 April 1990
+  Ty Coon, President of Vice
+
+That's all there is to it!
diff --git a/lib/ccan/endian/_info b/lib/ccan/endian/_info
new file mode 100644
index 0000000000..5d4d65ff74
--- /dev/null
+++ b/lib/ccan/endian/_info
@@ -0,0 +1,53 @@
+#include <stdio.h>
+#include <string.h>
+#include "config.h"
+
+/**
+ * endian - endian conversion macros for simple types
+ *
+ * Portable protocols (such as on-disk formats, or network protocols)
+ * are often defined to be a particular endian: little-endian (least
+ * significant bytes first) or big-endian (most significant bytes
+ * first).
+ *
+ * Similarly, some CPUs lay out values in memory in little-endian
+ * order (most commonly, Intel's 8086 and derivatives), or big-endian
+ * order (almost everyone else).
+ *
+ * This module provides conversion routines, inspired by the linux kernel.
+ *
+ * Example:
+ *	#include <stdio.h>
+ *	#include <err.h>
+ *	#include <ccan/endian/endian.h>
+ *
+ *	//
+ *	int main(int argc, char *argv[])
+ *	{
+ *		uint32_t value;
+ *
+ *		if (argc != 2)
+ *			errx(1, "Usage: %s <value>", argv[0]);
+ *
+ *		value = atoi(argv[1]);
+ *		printf("native:        %08x\n", value);
+ *		printf("little-endian: %08x\n", cpu_to_le32(value));
+ *		printf("big-endian:    %08x\n", cpu_to_be32(value));
+ *		printf("byte-reversed: %08x\n", bswap_32(value));
+ *		exit(0);
+ *	}
+ *
+ * License: LGPL (2 or any later version)
+ * Author: Rusty Russell <rusty@rustcorp.com.au>
+ */
+int main(int argc, char *argv[])
+{
+	if (argc != 2)
+		return 1;
+
+	if (strcmp(argv[1], "depends") == 0)
+		/* Nothing */
+		return 0;
+
+	return 1;
+}
diff --git a/lib/ccan/endian/endian.h b/lib/ccan/endian/endian.h
new file mode 100644
index 0000000000..baee60be14
--- /dev/null
+++ b/lib/ccan/endian/endian.h
@@ -0,0 +1,226 @@
+#ifndef CCAN_ENDIAN_H
+#define CCAN_ENDIAN_H
+#include <stdint.h>
+#include "config.h"
+
+#if HAVE_BYTESWAP_H
+#include <byteswap.h>
+#else
+/**
+ * bswap_16 - reverse bytes in a uint16_t value.
+ * @val: value whose bytes to swap.
+ *
+ * Example:
+ *	// Output contains "1024 is 4 as two bytes reversed"
+ *	printf("1024 is %u as two bytes reversed\n", bswap_16(1024));
+ */
+static inline uint16_t bswap_16(uint16_t val)
+{
+	return ((val & (uint16_t)0x00ffU) << 8)
+		| ((val & (uint16_t)0xff00U) >> 8);
+}
+
+/**
+ * bswap_32 - reverse bytes in a uint32_t value.
+ * @val: value whose bytes to swap.
+ *
+ * Example:
+ *	// Output contains "1024 is 262144 as four bytes reversed"
+ *	printf("1024 is %u as four bytes reversed\n", bswap_32(1024));
+ */
+static inline uint32_t bswap_32(uint32_t val)
+{
+	return ((val & (uint32_t)0x000000ffUL) << 24)
+		| ((val & (uint32_t)0x0000ff00UL) <<  8)
+		| ((val & (uint32_t)0x00ff0000UL) >>  8)
+		| ((val & (uint32_t)0xff000000UL) >> 24);
+}
+#endif /* !HAVE_BYTESWAP_H */
+
+#if !HAVE_BSWAP_64
+/**
+ * bswap_64 - reverse bytes in a uint64_t value.
+ * @val: value whose bytes to swap.
+ *
+ * Example:
+ *	// Output contains "1024 is 1125899906842624 as eight bytes reversed"
+ *	printf("1024 is %llu as eight bytes reversed\n",
+ *		(unsigned long long)bswap_64(1024));
+ */
+static inline uint64_t bswap_64(uint64_t val)
+{
+	return ((val & (uint64_t)0x00000000000000ffULL) << 56)
+		| ((val & (uint64_t)0x000000000000ff00ULL) << 40)
+		| ((val & (uint64_t)0x0000000000ff0000ULL) << 24)
+		| ((val & (uint64_t)0x00000000ff000000ULL) <<  8)
+		| ((val & (uint64_t)0x000000ff00000000ULL) >>  8)
+		| ((val & (uint64_t)0x0000ff0000000000ULL) >> 24)
+		| ((val & (uint64_t)0x00ff000000000000ULL) >> 40)
+		| ((val & (uint64_t)0xff00000000000000ULL) >> 56);
+}
+#endif
+
+/* Sanity check the defines.  We don't handle weird endianness. */
+#if !HAVE_LITTLE_ENDIAN && !HAVE_BIG_ENDIAN
+#error "Unknown endian"
+#elif HAVE_LITTLE_ENDIAN && HAVE_BIG_ENDIAN
+#error "Can't compile for both big and little endian."
+#endif
+
+/**
+ * cpu_to_le64 - convert a uint64_t value to little-endian
+ * @native: value to convert
+ */
+static inline uint64_t cpu_to_le64(uint64_t native)
+{
+#if HAVE_LITTLE_ENDIAN
+	return native;
+#else
+	return bswap_64(native);
+#endif
+}
+
+/**
+ * cpu_to_le32 - convert a uint32_t value to little-endian
+ * @native: value to convert
+ */
+static inline uint32_t cpu_to_le32(uint32_t native)
+{
+#if HAVE_LITTLE_ENDIAN
+	return native;
+#else
+	return bswap_32(native);
+#endif
+}
+
+/**
+ * cpu_to_le16 - convert a uint16_t value to little-endian
+ * @native: value to convert
+ */
+static inline uint16_t cpu_to_le16(uint16_t native)
+{
+#if HAVE_LITTLE_ENDIAN
+	return native;
+#else
+	return bswap_16(native);
+#endif
+}
+
+/**
+ * le64_to_cpu - convert a little-endian uint64_t value
+ * @le_val: little-endian value to convert
+ */
+static inline uint64_t le64_to_cpu(uint64_t le_val)
+{
+#if HAVE_LITTLE_ENDIAN
+	return le_val;
+#else
+	return bswap_64(le_val);
+#endif
+}
+
+/**
+ * le32_to_cpu - convert a little-endian uint32_t value
+ * @le_val: little-endian value to convert
+ */
+static inline uint32_t le32_to_cpu(uint32_t le_val)
+{
+#if HAVE_LITTLE_ENDIAN
+	return le_val;
+#else
+	return bswap_32(le_val);
+#endif
+}
+
+/**
+ * le16_to_cpu - convert a little-endian uint16_t value
+ * @le_val: little-endian value to convert
+ */
+static inline uint16_t le16_to_cpu(uint16_t le_val)
+{
+#if HAVE_LITTLE_ENDIAN
+	return le_val;
+#else
+	return bswap_16(le_val);
+#endif
+}
+
+/**
+ * cpu_to_be64 - convert a uint64_t value to big endian.
+ * @native: value to convert
+ */
+static inline uint64_t cpu_to_be64(uint64_t native)
+{
+#if HAVE_LITTLE_ENDIAN
+	return bswap_64(native);
+#else
+	return native;
+#endif
+}
+
+/**
+ * cpu_to_be32 - convert a uint32_t value to big endian.
+ * @native: value to convert
+ */
+static inline uint32_t cpu_to_be32(uint32_t native)
+{
+#if HAVE_LITTLE_ENDIAN
+	return bswap_32(native);
+#else
+	return native;
+#endif
+}
+
+/**
+ * cpu_to_be16 - convert a uint16_t value to big endian.
+ * @native: value to convert
+ */
+static inline uint16_t cpu_to_be16(uint16_t native)
+{
+#if HAVE_LITTLE_ENDIAN
+	return bswap_16(native);
+#else
+	return native;
+#endif
+}
+
+/**
+ * be64_to_cpu - convert a big-endian uint64_t value
+ * @be_val: big-endian value to convert
+ */
+static inline uint64_t be64_to_cpu(uint64_t be_val)
+{
+#if HAVE_LITTLE_ENDIAN
+	return bswap_64(be_val);
+#else
+	return be_val;
+#endif
+}
+
+/**
+ * be32_to_cpu - convert a big-endian uint32_t value
+ * @be_val: big-endian value to convert
+ */
+static inline uint32_t be32_to_cpu(uint32_t be_val)
+{
+#if HAVE_LITTLE_ENDIAN
+	return bswap_32(be_val);
+#else
+	return be_val;
+#endif
+}
+
+/**
+ * be16_to_cpu - convert a big-endian uint16_t value
+ * @be_val: big-endian value to convert
+ */
+static inline uint16_t be16_to_cpu(uint16_t be_val)
+{
+#if HAVE_LITTLE_ENDIAN
+	return bswap_16(be_val);
+#else
+	return be_val;
+#endif
+}
+
+#endif /* CCAN_ENDIAN_H */
diff --git a/lib/ccan/endian/test/run.c b/lib/ccan/endian/test/run.c
new file mode 100644
index 0000000000..a00fce74e4
--- /dev/null
+++ b/lib/ccan/endian/test/run.c
@@ -0,0 +1,106 @@
+#include <ccan/endian/endian.h>
+#include <stdlib.h>
+#include <stddef.h>
+#include <ccan/tap/tap.h>
+
+int main(int argc, char *argv[])
+{
+	union {
+		uint64_t u64;
+		unsigned char u64_bytes[8];
+	} u64;
+	union {
+		uint32_t u32;
+		unsigned char u32_bytes[4];
+	} u32;
+	union {
+		uint16_t u16;
+		unsigned char u16_bytes[2];
+	} u16;
+
+	plan_tests(48);
+
+	/* Straight swap tests. */
+	u64.u64_bytes[0] = 0x00;
+	u64.u64_bytes[1] = 0x11;
+	u64.u64_bytes[2] = 0x22;
+	u64.u64_bytes[3] = 0x33;
+	u64.u64_bytes[4] = 0x44;
+	u64.u64_bytes[5] = 0x55;
+	u64.u64_bytes[6] = 0x66;
+	u64.u64_bytes[7] = 0x77;
+	u64.u64 = bswap_64(u64.u64);
+	ok1(u64.u64_bytes[7] == 0x00);
+	ok1(u64.u64_bytes[6] == 0x11);
+	ok1(u64.u64_bytes[5] == 0x22);
+	ok1(u64.u64_bytes[4] == 0x33);
+	ok1(u64.u64_bytes[3] == 0x44);
+	ok1(u64.u64_bytes[2] == 0x55);
+	ok1(u64.u64_bytes[1] == 0x66);
+	ok1(u64.u64_bytes[0] == 0x77);
+
+	u32.u32_bytes[0] = 0x00;
+	u32.u32_bytes[1] = 0x11;
+	u32.u32_bytes[2] = 0x22;
+	u32.u32_bytes[3] = 0x33;
+	u32.u32 = bswap_32(u32.u32);
+	ok1(u32.u32_bytes[3] == 0x00);
+	ok1(u32.u32_bytes[2] == 0x11);
+	ok1(u32.u32_bytes[1] == 0x22);
+	ok1(u32.u32_bytes[0] == 0x33);
+
+	u16.u16_bytes[0] = 0x00;
+	u16.u16_bytes[1] = 0x11;
+	u16.u16 = bswap_16(u16.u16);
+	ok1(u16.u16_bytes[1] == 0x00);
+	ok1(u16.u16_bytes[0] == 0x11);
+
+	/* Endian tests. */
+	u64.u64 = cpu_to_le64(0x0011223344556677ULL);
+	ok1(u64.u64_bytes[0] == 0x77);
+	ok1(u64.u64_bytes[1] == 0x66);
+	ok1(u64.u64_bytes[2] == 0x55);
+	ok1(u64.u64_bytes[3] == 0x44);
+	ok1(u64.u64_bytes[4] == 0x33);
+	ok1(u64.u64_bytes[5] == 0x22);
+	ok1(u64.u64_bytes[6] == 0x11);
+	ok1(u64.u64_bytes[7] == 0x00);
+	ok1(le64_to_cpu(u64.u64) == 0x0011223344556677ULL);
+
+	u64.u64 = cpu_to_be64(0x0011223344556677ULL);
+	ok1(u64.u64_bytes[7] == 0x77);
+	ok1(u64.u64_bytes[6] == 0x66);
+	ok1(u64.u64_bytes[5] == 0x55);
+	ok1(u64.u64_bytes[4] == 0x44);
+	ok1(u64.u64_bytes[3] == 0x33);
+	ok1(u64.u64_bytes[2] == 0x22);
+	ok1(u64.u64_bytes[1] == 0x11);
+	ok1(u64.u64_bytes[0] == 0x00);
+	ok1(be64_to_cpu(u64.u64) == 0x0011223344556677ULL);
+
+	u32.u32 = cpu_to_le32(0x00112233);
+	ok1(u32.u32_bytes[0] == 0x33);
+	ok1(u32.u32_bytes[1] == 0x22);
+	ok1(u32.u32_bytes[2] == 0x11);
+	ok1(u32.u32_bytes[3] == 0x00);
+	ok1(le32_to_cpu(u32.u32) == 0x00112233);
+
+	u32.u32 = cpu_to_be32(0x00112233);
+	ok1(u32.u32_bytes[3] == 0x33);
+	ok1(u32.u32_bytes[2] == 0x22);
+	ok1(u32.u32_bytes[1] == 0x11);
+	ok1(u32.u32_bytes[0] == 0x00);
+	ok1(be32_to_cpu(u32.u32) == 0x00112233);
+
+	u16.u16 = cpu_to_le16(0x0011);
+	ok1(u16.u16_bytes[0] == 0x11);
+	ok1(u16.u16_bytes[1] == 0x00);
+	ok1(le16_to_cpu(u16.u16) == 0x0011);
+
+	u16.u16 = cpu_to_be16(0x0011);
+	ok1(u16.u16_bytes[1] == 0x11);
+	ok1(u16.u16_bytes[0] == 0x00);
+	ok1(be16_to_cpu(u16.u16) == 0x0011);
+
+	exit(exit_status());
+}
diff --git a/lib/ccan/hash/_info b/lib/ccan/hash/_info
new file mode 100644
index 0000000000..5aeb912136
--- /dev/null
+++ b/lib/ccan/hash/_info
@@ -0,0 +1,31 @@
+#include <string.h>
+#include <stdio.h>
+
+/**
+ * hash - routines for hashing bytes
+ *
+ * When creating a hash table it's important to have a hash function
+ * which mixes well and is fast.  This package supplies such functions.
+ *
+ * The hash functions come in two flavors: the normal ones and the
+ * stable ones.  The normal ones can vary from machine-to-machine and
+ * may change if we find better or faster hash algorithms in future.
+ * The stable ones will always give the same results on any computer,
+ * and on any version of this package.
+ *
+ * License: Public Domain
+ * Maintainer: Rusty Russell <rusty@rustcorp.com.au>
+ * Author: Bob Jenkins <bob_jenkins@burtleburtle.net>
+ */
+int main(int argc, char *argv[])
+{
+	if (argc != 2)
+		return 1;
+
+	if (strcmp(argv[1], "depends") == 0) {
+		printf("ccan/build_assert\n");
+		return 0;
+	}
+
+	return 1;
+}
diff --git a/lib/ccan/hash/hash.c b/lib/ccan/hash/hash.c
new file mode 100644
index 0000000000..0fd6109513
--- /dev/null
+++ b/lib/ccan/hash/hash.c
@@ -0,0 +1,925 @@
+/*
+-------------------------------------------------------------------------------
+lookup3.c, by Bob Jenkins, May 2006, Public Domain.
+
+These are functions for producing 32-bit hashes for hash table lookup.
+hash_word(), hashlittle(), hashlittle2(), hashbig(), mix(), and final()
+are externally useful functions.  Routines to test the hash are included
+if SELF_TEST is defined.  You can use this free for any purpose.  It's in
+the public domain.  It has no warranty.
+
+You probably want to use hashlittle().  hashlittle() and hashbig()
+hash byte arrays.  hashlittle() is is faster than hashbig() on
+little-endian machines.  Intel and AMD are little-endian machines.
+On second thought, you probably want hashlittle2(), which is identical to
+hashlittle() except it returns two 32-bit hashes for the price of one.
+You could implement hashbig2() if you wanted but I haven't bothered here.
+
+If you want to find a hash of, say, exactly 7 integers, do
+  a = i1;  b = i2;  c = i3;
+  mix(a,b,c);
+  a += i4; b += i5; c += i6;
+  mix(a,b,c);
+  a += i7;
+  final(a,b,c);
+then use c as the hash value.  If you have a variable length array of
+4-byte integers to hash, use hash_word().  If you have a byte array (like
+a character string), use hashlittle().  If you have several byte arrays, or
+a mix of things, see the comments above hashlittle().
+
+Why is this so big?  I read 12 bytes at a time into 3 4-byte integers,
+then mix those integers.  This is fast (you can do a lot more thorough
+mixing with 12*3 instructions on 3 integers than you can with 3 instructions
+on 1 byte), but shoehorning those bytes into integers efficiently is messy.
+-------------------------------------------------------------------------------
+*/
+//#define SELF_TEST 1
+
+#if 0
+#include <stdio.h>      /* defines printf for tests */
+#include <time.h>       /* defines time_t for timings in the test */
+#include <stdint.h>     /* defines uint32_t etc */
+#include <sys/param.h>  /* attempt to define endianness */
+
+#ifdef linux
+# include <endian.h>    /* attempt to define endianness */
+#endif
+
+/*
+ * My best guess at if you are big-endian or little-endian.  This may
+ * need adjustment.
+ */
+#if (defined(__BYTE_ORDER) && defined(__LITTLE_ENDIAN) && \
+     __BYTE_ORDER == __LITTLE_ENDIAN) || \
+    (defined(i386) || defined(__i386__) || defined(__i486__) || \
+     defined(__i586__) || defined(__i686__) || defined(__x86_64) || \
+     defined(vax) || defined(MIPSEL))
+# define HASH_LITTLE_ENDIAN 1
+# define HASH_BIG_ENDIAN 0
+#elif (defined(__BYTE_ORDER) && defined(__BIG_ENDIAN) && \
+       __BYTE_ORDER == __BIG_ENDIAN) || \
+      (defined(sparc) || defined(POWERPC) || defined(mc68000) || defined(sel))
+# define HASH_LITTLE_ENDIAN 0
+# define HASH_BIG_ENDIAN 1
+#else
+# error Unknown endian
+#endif
+#endif /* old hash.c headers. */
+
+#include "hash.h"
+
+#if HAVE_LITTLE_ENDIAN
+#define HASH_LITTLE_ENDIAN 1
+#define HASH_BIG_ENDIAN 0
+#elif HAVE_BIG_ENDIAN
+#define HASH_LITTLE_ENDIAN 0
+#define HASH_BIG_ENDIAN 1
+#else
+#error Unknown endian
+#endif
+
+#define hashsize(n) ((uint32_t)1<<(n))
+#define hashmask(n) (hashsize(n)-1)
+#define rot(x,k) (((x)<<(k)) | ((x)>>(32-(k))))
+
+/*
+-------------------------------------------------------------------------------
+mix -- mix 3 32-bit values reversibly.
+
+This is reversible, so any information in (a,b,c) before mix() is
+still in (a,b,c) after mix().
+
+If four pairs of (a,b,c) inputs are run through mix(), or through
+mix() in reverse, there are at least 32 bits of the output that
+are sometimes the same for one pair and different for another pair.
+This was tested for:
+* pairs that differed by one bit, by two bits, in any combination
+  of top bits of (a,b,c), or in any combination of bottom bits of
+  (a,b,c).
+* "differ" is defined as +, -, ^, or ~^.  For + and -, I transformed
+  the output delta to a Gray code (a^(a>>1)) so a string of 1's (as
+  is commonly produced by subtraction) look like a single 1-bit
+  difference.
+* the base values were pseudorandom, all zero but one bit set, or
+  all zero plus a counter that starts at zero.
+
+Some k values for my "a-=c; a^=rot(c,k); c+=b;" arrangement that
+satisfy this are
+    4  6  8 16 19  4
+    9 15  3 18 27 15
+   14  9  3  7 17  3
+Well, "9 15 3 18 27 15" didn't quite get 32 bits diffing
+for "differ" defined as + with a one-bit base and a two-bit delta.  I
+used http://burtleburtle.net/bob/hash/avalanche.html to choose
+the operations, constants, and arrangements of the variables.
+
+This does not achieve avalanche.  There are input bits of (a,b,c)
+that fail to affect some output bits of (a,b,c), especially of a.  The
+most thoroughly mixed value is c, but it doesn't really even achieve
+avalanche in c.
+
+This allows some parallelism.  Read-after-writes are good at doubling
+the number of bits affected, so the goal of mixing pulls in the opposite
+direction as the goal of parallelism.  I did what I could.  Rotates
+seem to cost as much as shifts on every machine I could lay my hands
+on, and rotates are much kinder to the top and bottom bits, so I used
+rotates.
+-------------------------------------------------------------------------------
+*/
+#define mix(a,b,c) \
+{ \
+  a -= c;  a ^= rot(c, 4);  c += b; \
+  b -= a;  b ^= rot(a, 6);  a += c; \
+  c -= b;  c ^= rot(b, 8);  b += a; \
+  a -= c;  a ^= rot(c,16);  c += b; \
+  b -= a;  b ^= rot(a,19);  a += c; \
+  c -= b;  c ^= rot(b, 4);  b += a; \
+}
+
+/*
+-------------------------------------------------------------------------------
+final -- final mixing of 3 32-bit values (a,b,c) into c
+
+Pairs of (a,b,c) values differing in only a few bits will usually
+produce values of c that look totally different.  This was tested for
+* pairs that differed by one bit, by two bits, in any combination
+  of top bits of (a,b,c), or in any combination of bottom bits of
+  (a,b,c).
+* "differ" is defined as +, -, ^, or ~^.  For + and -, I transformed
+  the output delta to a Gray code (a^(a>>1)) so a string of 1's (as
+  is commonly produced by subtraction) look like a single 1-bit
+  difference.
+* the base values were pseudorandom, all zero but one bit set, or
+  all zero plus a counter that starts at zero.
+
+These constants passed:
+ 14 11 25 16 4 14 24
+ 12 14 25 16 4 14 24
+and these came close:
+  4  8 15 26 3 22 24
+ 10  8 15 26 3 22 24
+ 11  8 15 26 3 22 24
+-------------------------------------------------------------------------------
+*/
+#define final(a,b,c) \
+{ \
+  c ^= b; c -= rot(b,14); \
+  a ^= c; a -= rot(c,11); \
+  b ^= a; b -= rot(a,25); \
+  c ^= b; c -= rot(b,16); \
+  a ^= c; a -= rot(c,4);  \
+  b ^= a; b -= rot(a,14); \
+  c ^= b; c -= rot(b,24); \
+}
+
+/*
+--------------------------------------------------------------------
+ This works on all machines.  To be useful, it requires
+ -- that the key be an array of uint32_t's, and
+ -- that the length be the number of uint32_t's in the key
+
+ The function hash_word() is identical to hashlittle() on little-endian
+ machines, and identical to hashbig() on big-endian machines,
+ except that the length has to be measured in uint32_ts rather than in
+ bytes.  hashlittle() is more complicated than hash_word() only because
+ hashlittle() has to dance around fitting the key bytes into registers.
+--------------------------------------------------------------------
+*/
+uint32_t hash_u32(
+const uint32_t *k,                   /* the key, an array of uint32_t values */
+size_t          length,               /* the length of the key, in uint32_ts */
+uint32_t        initval)         /* the previous hash, or an arbitrary value */
+{
+  uint32_t a,b,c;
+
+  /* Set up the internal state */
+  a = b = c = 0xdeadbeef + (((uint32_t)length)<<2) + initval;
+
+  /*------------------------------------------------- handle most of the key */
+  while (length > 3)
+  {
+    a += k[0];
+    b += k[1];
+    c += k[2];
+    mix(a,b,c);
+    length -= 3;
+    k += 3;
+  }
+
+  /*------------------------------------------- handle the last 3 uint32_t's */
+  switch(length)                     /* all the case statements fall through */
+  {
+  case 3 : c+=k[2];
+  case 2 : b+=k[1];
+  case 1 : a+=k[0];
+    final(a,b,c);
+  case 0:     /* case 0: nothing left to add */
+    break;
+  }
+  /*------------------------------------------------------ report the result */
+  return c;
+}
+
+/*
+-------------------------------------------------------------------------------
+hashlittle() -- hash a variable-length key into a 32-bit value
+  k       : the key (the unaligned variable-length array of bytes)
+  length  : the length of the key, counting by bytes
+  val2    : IN: can be any 4-byte value OUT: second 32 bit hash.
+Returns a 32-bit value.  Every bit of the key affects every bit of
+the return value.  Two keys differing by one or two bits will have
+totally different hash values.  Note that the return value is better
+mixed than val2, so use that first.
+
+The best hash table sizes are powers of 2.  There is no need to do
+mod a prime (mod is sooo slow!).  If you need less than 32 bits,
+use a bitmask.  For example, if you need only 10 bits, do
+  h = (h & hashmask(10));
+In which case, the hash table should have hashsize(10) elements.
+
+If you are hashing n strings (uint8_t **)k, do it like this:
+  for (i=0, h=0; i<n; ++i) h = hashlittle( k[i], len[i], h);
+
+By Bob Jenkins, 2006.  bob_jenkins@burtleburtle.net.  You may use this
+code any way you wish, private, educational, or commercial.  It's free.
+
+Use for hash table lookup, or anything where one collision in 2^^32 is
+acceptable.  Do NOT use for cryptographic purposes.
+-------------------------------------------------------------------------------
+*/
+
+static uint32_t hashlittle( const void *key, size_t length, uint32_t *val2 )
+{
+  uint32_t a,b,c;                                          /* internal state */
+  union { const void *ptr; size_t i; } u;     /* needed for Mac Powerbook G4 */
+
+  /* Set up the internal state */
+  a = b = c = 0xdeadbeef + ((uint32_t)length) + *val2;
+
+  u.ptr = key;
+  if (HASH_LITTLE_ENDIAN && ((u.i & 0x3) == 0)) {
+    const uint32_t *k = (const uint32_t *)key;         /* read 32-bit chunks */
+    const uint8_t  *k8;
+
+    /*------ all but last block: aligned reads and affect 32 bits of (a,b,c) */
+    while (length > 12)
+    {
+      a += k[0];
+      b += k[1];
+      c += k[2];
+      mix(a,b,c);
+      length -= 12;
+      k += 3;
+    }
+
+    /*----------------------------- handle the last (probably partial) block */
+    /*
+     * "k[2]&0xffffff" actually reads beyond the end of the string, but
+     * then masks off the part it's not allowed to read.  Because the
+     * string is aligned, the masked-off tail is in the same word as the
+     * rest of the string.  Every machine with memory protection I've seen
+     * does it on word boundaries, so is OK with this.  But VALGRIND will
+     * still catch it and complain.  The masking trick does make the hash
+     * noticably faster for short strings (like English words).
+     *
+     * Not on my testing with gcc 4.5 on an intel i5 CPU, at least --RR.
+     */
+#if 0
+    switch(length)
+    {
+    case 12: c+=k[2]; b+=k[1]; a+=k[0]; break;
+    case 11: c+=k[2]&0xffffff; b+=k[1]; a+=k[0]; break;
+    case 10: c+=k[2]&0xffff; b+=k[1]; a+=k[0]; break;
+    case 9 : c+=k[2]&0xff; b+=k[1]; a+=k[0]; break;
+    case 8 : b+=k[1]; a+=k[0]; break;
+    case 7 : b+=k[1]&0xffffff; a+=k[0]; break;
+    case 6 : b+=k[1]&0xffff; a+=k[0]; break;
+    case 5 : b+=k[1]&0xff; a+=k[0]; break;
+    case 4 : a+=k[0]; break;
+    case 3 : a+=k[0]&0xffffff; break;
+    case 2 : a+=k[0]&0xffff; break;
+    case 1 : a+=k[0]&0xff; break;
+    case 0 : return c;              /* zero length strings require no mixing */
+    }
+
+#else /* make valgrind happy */
+
+    k8 = (const uint8_t *)k;
+    switch(length)
+    {
+    case 12: c+=k[2]; b+=k[1]; a+=k[0]; break;
+    case 11: c+=((uint32_t)k8[10])<<16;  /* fall through */
+    case 10: c+=((uint32_t)k8[9])<<8;    /* fall through */
+    case 9 : c+=k8[8];                   /* fall through */
+    case 8 : b+=k[1]; a+=k[0]; break;
+    case 7 : b+=((uint32_t)k8[6])<<16;   /* fall through */
+    case 6 : b+=((uint32_t)k8[5])<<8;    /* fall through */
+    case 5 : b+=k8[4];                   /* fall through */
+    case 4 : a+=k[0]; break;
+    case 3 : a+=((uint32_t)k8[2])<<16;   /* fall through */
+    case 2 : a+=((uint32_t)k8[1])<<8;    /* fall through */
+    case 1 : a+=k8[0]; break;
+    case 0 : return c;
+    }
+
+#endif /* !valgrind */
+
+  } else if (HASH_LITTLE_ENDIAN && ((u.i & 0x1) == 0)) {
+    const uint16_t *k = (const uint16_t *)key;         /* read 16-bit chunks */
+    const uint8_t  *k8;
+
+    /*--------------- all but last block: aligned reads and different mixing */
+    while (length > 12)
+    {
+      a += k[0] + (((uint32_t)k[1])<<16);
+      b += k[2] + (((uint32_t)k[3])<<16);
+      c += k[4] + (((uint32_t)k[5])<<16);
+      mix(a,b,c);
+      length -= 12;
+      k += 6;
+    }
+
+    /*----------------------------- handle the last (probably partial) block */
+    k8 = (const uint8_t *)k;
+    switch(length)
+    {
+    case 12: c+=k[4]+(((uint32_t)k[5])<<16);
+             b+=k[2]+(((uint32_t)k[3])<<16);
+             a+=k[0]+(((uint32_t)k[1])<<16);
+             break;
+    case 11: c+=((uint32_t)k8[10])<<16;     /* fall through */
+    case 10: c+=k[4];
+             b+=k[2]+(((uint32_t)k[3])<<16);
+             a+=k[0]+(((uint32_t)k[1])<<16);
+             break;
+    case 9 : c+=k8[8];                      /* fall through */
+    case 8 : b+=k[2]+(((uint32_t)k[3])<<16);
+             a+=k[0]+(((uint32_t)k[1])<<16);
+             break;
+    case 7 : b+=((uint32_t)k8[6])<<16;      /* fall through */
+    case 6 : b+=k[2];
+             a+=k[0]+(((uint32_t)k[1])<<16);
+             break;
+    case 5 : b+=k8[4];                      /* fall through */
+    case 4 : a+=k[0]+(((uint32_t)k[1])<<16);
+             break;
+    case 3 : a+=((uint32_t)k8[2])<<16;      /* fall through */
+    case 2 : a+=k[0];
+             break;
+    case 1 : a+=k8[0];
+             break;
+    case 0 : return c;                     /* zero length requires no mixing */
+    }
+
+  } else {                        /* need to read the key one byte at a time */
+    const uint8_t *k = (const uint8_t *)key;
+
+    /*--------------- all but the last block: affect some 32 bits of (a,b,c) */
+    while (length > 12)
+    {
+      a += k[0];
+      a += ((uint32_t)k[1])<<8;
+      a += ((uint32_t)k[2])<<16;
+      a += ((uint32_t)k[3])<<24;
+      b += k[4];
+      b += ((uint32_t)k[5])<<8;
+      b += ((uint32_t)k[6])<<16;
+      b += ((uint32_t)k[7])<<24;
+      c += k[8];
+      c += ((uint32_t)k[9])<<8;
+      c += ((uint32_t)k[10])<<16;
+      c += ((uint32_t)k[11])<<24;
+      mix(a,b,c);
+      length -= 12;
+      k += 12;
+    }
+
+    /*-------------------------------- last block: affect all 32 bits of (c) */
+    switch(length)                   /* all the case statements fall through */
+    {
+    case 12: c+=((uint32_t)k[11])<<24;
+    case 11: c+=((uint32_t)k[10])<<16;
+    case 10: c+=((uint32_t)k[9])<<8;
+    case 9 : c+=k[8];
+    case 8 : b+=((uint32_t)k[7])<<24;
+    case 7 : b+=((uint32_t)k[6])<<16;
+    case 6 : b+=((uint32_t)k[5])<<8;
+    case 5 : b+=k[4];
+    case 4 : a+=((uint32_t)k[3])<<24;
+    case 3 : a+=((uint32_t)k[2])<<16;
+    case 2 : a+=((uint32_t)k[1])<<8;
+    case 1 : a+=k[0];
+             break;
+    case 0 : return c;
+    }
+  }
+
+  final(a,b,c);
+  *val2 = b;
+  return c;
+}
+
+/*
+ * hashbig():
+ * This is the same as hash_word() on big-endian machines.  It is different
+ * from hashlittle() on all machines.  hashbig() takes advantage of
+ * big-endian byte ordering.
+ */
+static uint32_t hashbig( const void *key, size_t length, uint32_t *val2)
+{
+  uint32_t a,b,c;
+  union { const void *ptr; size_t i; } u; /* to cast key to (size_t) happily */
+
+  /* Set up the internal state */
+  a = b = c = 0xdeadbeef + ((uint32_t)length) + *val2;
+
+  u.ptr = key;
+  if (HASH_BIG_ENDIAN && ((u.i & 0x3) == 0)) {
+    const uint32_t *k = (const uint32_t *)key;         /* read 32-bit chunks */
+    const uint8_t  *k8;
+
+    /*------ all but last block: aligned reads and affect 32 bits of (a,b,c) */
+    while (length > 12)
+    {
+      a += k[0];
+      b += k[1];
+      c += k[2];
+      mix(a,b,c);
+      length -= 12;
+      k += 3;
+    }
+
+    /*----------------------------- handle the last (probably partial) block */
+    /*
+     * "k[2]<<8" actually reads beyond the end of the string, but
+     * then shifts out the part it's not allowed to read.  Because the
+     * string is aligned, the illegal read is in the same word as the
+     * rest of the string.  Every machine with memory protection I've seen
+     * does it on word boundaries, so is OK with this.  But VALGRIND will
+     * still catch it and complain.  The masking trick does make the hash
+     * noticably faster for short strings (like English words).
+     *
+     * Not on my testing with gcc 4.5 on an intel i5 CPU, at least --RR.
+     */
+#if 0
+    switch(length)
+    {
+    case 12: c+=k[2]; b+=k[1]; a+=k[0]; break;
+    case 11: c+=k[2]&0xffffff00; b+=k[1]; a+=k[0]; break;
+    case 10: c+=k[2]&0xffff0000; b+=k[1]; a+=k[0]; break;
+    case 9 : c+=k[2]&0xff000000; b+=k[1]; a+=k[0]; break;
+    case 8 : b+=k[1]; a+=k[0]; break;
+    case 7 : b+=k[1]&0xffffff00; a+=k[0]; break;
+    case 6 : b+=k[1]&0xffff0000; a+=k[0]; break;
+    case 5 : b+=k[1]&0xff000000; a+=k[0]; break;
+    case 4 : a+=k[0]; break;
+    case 3 : a+=k[0]&0xffffff00; break;
+    case 2 : a+=k[0]&0xffff0000; break;
+    case 1 : a+=k[0]&0xff000000; break;
+    case 0 : return c;              /* zero length strings require no mixing */
+    }
+
+#else  /* make valgrind happy */
+
+    k8 = (const uint8_t *)k;
+    switch(length)                   /* all the case statements fall through */
+    {
+    case 12: c+=k[2]; b+=k[1]; a+=k[0]; break;
+    case 11: c+=((uint32_t)k8[10])<<8;  /* fall through */
+    case 10: c+=((uint32_t)k8[9])<<16;  /* fall through */
+    case 9 : c+=((uint32_t)k8[8])<<24;  /* fall through */
+    case 8 : b+=k[1]; a+=k[0]; break;
+    case 7 : b+=((uint32_t)k8[6])<<8;   /* fall through */
+    case 6 : b+=((uint32_t)k8[5])<<16;  /* fall through */
+    case 5 : b+=((uint32_t)k8[4])<<24;  /* fall through */
+    case 4 : a+=k[0]; break;
+    case 3 : a+=((uint32_t)k8[2])<<8;   /* fall through */
+    case 2 : a+=((uint32_t)k8[1])<<16;  /* fall through */
+    case 1 : a+=((uint32_t)k8[0])<<24; break;
+    case 0 : return c;
+    }
+
+#endif /* !VALGRIND */
+
+  } else {                        /* need to read the key one byte at a time */
+    const uint8_t *k = (const uint8_t *)key;
+
+    /*--------------- all but the last block: affect some 32 bits of (a,b,c) */
+    while (length > 12)
+    {
+      a += ((uint32_t)k[0])<<24;
+      a += ((uint32_t)k[1])<<16;
+      a += ((uint32_t)k[2])<<8;
+      a += ((uint32_t)k[3]);
+      b += ((uint32_t)k[4])<<24;
+      b += ((uint32_t)k[5])<<16;
+      b += ((uint32_t)k[6])<<8;
+      b += ((uint32_t)k[7]);
+      c += ((uint32_t)k[8])<<24;
+      c += ((uint32_t)k[9])<<16;
+      c += ((uint32_t)k[10])<<8;
+      c += ((uint32_t)k[11]);
+      mix(a,b,c);
+      length -= 12;
+      k += 12;
+    }
+
+    /*-------------------------------- last block: affect all 32 bits of (c) */
+    switch(length)                   /* all the case statements fall through */
+    {
+    case 12: c+=k[11];
+    case 11: c+=((uint32_t)k[10])<<8;
+    case 10: c+=((uint32_t)k[9])<<16;
+    case 9 : c+=((uint32_t)k[8])<<24;
+    case 8 : b+=k[7];
+    case 7 : b+=((uint32_t)k[6])<<8;
+    case 6 : b+=((uint32_t)k[5])<<16;
+    case 5 : b+=((uint32_t)k[4])<<24;
+    case 4 : a+=k[3];
+    case 3 : a+=((uint32_t)k[2])<<8;
+    case 2 : a+=((uint32_t)k[1])<<16;
+    case 1 : a+=((uint32_t)k[0])<<24;
+             break;
+    case 0 : return c;
+    }
+  }
+
+  final(a,b,c);
+  *val2 = b;
+  return c;
+}
+
+/* I basically use hashlittle here, but use native endian within each
+ * element.  This delivers least-surprise: hash such as "int arr[] = {
+ * 1, 2 }; hash_stable(arr, 2, 0);" will be the same on big and little
+ * endian machines, even though a bytewise hash wouldn't be. */
+uint64_t hash64_stable_64(const void *key, size_t n, uint64_t base)
+{
+	const uint64_t *k = key;
+	uint32_t a,b,c;
+
+	/* Set up the internal state */
+	a = b = c = 0xdeadbeef + ((uint32_t)n*8) + (base >> 32) + base;
+
+	while (n > 3) {
+		a += (uint32_t)k[0];
+		b += (uint32_t)(k[0] >> 32);
+		c += (uint32_t)k[1];
+		mix(a,b,c);
+		a += (uint32_t)(k[1] >> 32);
+		b += (uint32_t)k[2];
+		c += (uint32_t)(k[2] >> 32);
+		mix(a,b,c);
+		n -= 3;
+		k += 3;
+	}
+	switch (n) {
+	case 2:
+		a += (uint32_t)k[0];
+		b += (uint32_t)(k[0] >> 32);
+		c += (uint32_t)k[1];
+		mix(a,b,c);
+		a += (uint32_t)(k[1] >> 32);
+		break;
+	case 1:
+		a += (uint32_t)k[0];
+		b += (uint32_t)(k[0] >> 32);
+		break;
+	case 0:
+		return c;
+	}
+	final(a,b,c);
+	return ((uint64_t)b << 32) | c;
+}
+
+uint64_t hash64_stable_32(const void *key, size_t n, uint64_t base)
+{
+	const uint32_t *k = key;
+	uint32_t a,b,c;
+
+	/* Set up the internal state */
+	a = b = c = 0xdeadbeef + ((uint32_t)n*4) + (base >> 32) + base;
+
+	while (n > 3) {
+		a += k[0];
+		b += k[1];
+		c += k[2];
+		mix(a,b,c);
+
+		n -= 3;
+		k += 3;
+	}
+	switch (n) {
+	case 2:
+		b += (uint32_t)k[1];
+	case 1:
+		a += (uint32_t)k[0];
+		break;
+	case 0:
+		return c;
+	}
+	final(a,b,c);
+	return ((uint64_t)b << 32) | c;
+}
+
+uint64_t hash64_stable_16(const void *key, size_t n, uint64_t base)
+{
+	const uint16_t *k = key;
+	uint32_t a,b,c;
+
+	/* Set up the internal state */
+	a = b = c = 0xdeadbeef + ((uint32_t)n*2) + (base >> 32) + base;
+
+	while (n > 6) {
+		a += (uint32_t)k[0] + ((uint32_t)k[1] << 16);
+		b += (uint32_t)k[2] + ((uint32_t)k[3] << 16);
+		c += (uint32_t)k[4] + ((uint32_t)k[5] << 16);
+		mix(a,b,c);
+
+		n -= 6;
+		k += 6;
+	}
+
+	switch (n) {
+	case 5:
+		c += (uint32_t)k[4];
+	case 4:
+		b += ((uint32_t)k[3] << 16);
+	case 3:
+		b += (uint32_t)k[2];
+	case 2:
+		a += ((uint32_t)k[1] << 16);
+	case 1:
+		a += (uint32_t)k[0];
+		break;
+	case 0:
+		return c;
+	}
+	final(a,b,c);
+	return ((uint64_t)b << 32) | c;
+}
+
+uint64_t hash64_stable_8(const void *key, size_t n, uint64_t base)
+{
+	uint32_t b32 = base + (base >> 32);
+	uint32_t lower = hashlittle(key, n, &b32);
+
+	return ((uint64_t)b32 << 32) | lower;
+}
+
+uint32_t hash_any(const void *key, size_t length, uint32_t base)
+{
+	if (HASH_BIG_ENDIAN)
+		return hashbig(key, length, &base);
+	else
+		return hashlittle(key, length, &base);
+}
+
+uint32_t hash_stable_64(const void *key, size_t n, uint32_t base)
+{
+	return hash64_stable_64(key, n, base);
+}
+
+uint32_t hash_stable_32(const void *key, size_t n, uint32_t base)
+{
+	return hash64_stable_32(key, n, base);
+}
+
+uint32_t hash_stable_16(const void *key, size_t n, uint32_t base)
+{
+	return hash64_stable_16(key, n, base);
+}
+
+uint32_t hash_stable_8(const void *key, size_t n, uint32_t base)
+{
+	return hashlittle(key, n, &base);
+}
+
+/* Jenkins' lookup8 is a 64 bit hash, but he says it's obsolete.  Use
+ * the plain one and recombine into 64 bits. */
+uint64_t hash64_any(const void *key, size_t length, uint64_t base)
+{
+	uint32_t b32 = base + (base >> 32);
+	uint32_t lower;
+
+	if (HASH_BIG_ENDIAN)
+		lower = hashbig(key, length, &b32);
+	else
+		lower = hashlittle(key, length, &b32);
+
+	return ((uint64_t)b32 << 32) | lower;
+}
+
+#ifdef SELF_TEST
+
+/* used for timings */
+void driver1()
+{
+  uint8_t buf[256];
+  uint32_t i;
+  uint32_t h=0;
+  time_t a,z;
+
+  time(&a);
+  for (i=0; i<256; ++i) buf[i] = 'x';
+  for (i=0; i<1; ++i)
+  {
+    h = hashlittle(&buf[0],1,h);
+  }
+  time(&z);
+  if (z-a > 0) printf("time %d %.8x\n", z-a, h);
+}
+
+/* check that every input bit changes every output bit half the time */
+#define HASHSTATE 1
+#define HASHLEN   1
+#define MAXPAIR 60
+#define MAXLEN  70
+void driver2()
+{
+  uint8_t qa[MAXLEN+1], qb[MAXLEN+2], *a = &qa[0], *b = &qb[1];
+  uint32_t c[HASHSTATE], d[HASHSTATE], i=0, j=0, k, l, m=0, z;
+  uint32_t e[HASHSTATE],f[HASHSTATE],g[HASHSTATE],h[HASHSTATE];
+  uint32_t x[HASHSTATE],y[HASHSTATE];
+  uint32_t hlen;
+
+  printf("No more than %d trials should ever be needed \n",MAXPAIR/2);
+  for (hlen=0; hlen < MAXLEN; ++hlen)
+  {
+    z=0;
+    for (i=0; i<hlen; ++i)  /*----------------------- for each input byte, */
+    {
+      for (j=0; j<8; ++j)   /*------------------------ for each input bit, */
+      {
+	for (m=1; m<8; ++m) /*------------ for several possible initvals, */
+	{
+	  for (l=0; l<HASHSTATE; ++l)
+	    e[l]=f[l]=g[l]=h[l]=x[l]=y[l]=~((uint32_t)0);
+
+	  /*---- check that every output bit is affected by that input bit */
+	  for (k=0; k<MAXPAIR; k+=2)
+	  {
+	    uint32_t finished=1;
+	    /* keys have one bit different */
+	    for (l=0; l<hlen+1; ++l) {a[l] = b[l] = (uint8_t)0;}
+	    /* have a and b be two keys differing in only one bit */
+	    a[i] ^= (k<<j);
+	    a[i] ^= (k>>(8-j));
+	     c[0] = hashlittle(a, hlen, m);
+	    b[i] ^= ((k+1)<<j);
+	    b[i] ^= ((k+1)>>(8-j));
+	     d[0] = hashlittle(b, hlen, m);
+	    /* check every bit is 1, 0, set, and not set at least once */
+	    for (l=0; l<HASHSTATE; ++l)
+	    {
+	      e[l] &= (c[l]^d[l]);
+	      f[l] &= ~(c[l]^d[l]);
+	      g[l] &= c[l];
+	      h[l] &= ~c[l];
+	      x[l] &= d[l];
+	      y[l] &= ~d[l];
+	      if (e[l]|f[l]|g[l]|h[l]|x[l]|y[l]) finished=0;
+	    }
+	    if (finished) break;
+	  }
+	  if (k>z) z=k;
+	  if (k==MAXPAIR)
+	  {
+	     printf("Some bit didn't change: ");
+	     printf("%.8x %.8x %.8x %.8x %.8x %.8x  ",
+	            e[0],f[0],g[0],h[0],x[0],y[0]);
+	     printf("i %d j %d m %d len %d\n", i, j, m, hlen);
+	  }
+	  if (z==MAXPAIR) goto done;
+	}
+      }
+    }
+   done:
+    if (z < MAXPAIR)
+    {
+      printf("Mix success  %2d bytes  %2d initvals  ",i,m);
+      printf("required  %d  trials\n", z/2);
+    }
+  }
+  printf("\n");
+}
+
+/* Check for reading beyond the end of the buffer and alignment problems */
+void driver3()
+{
+  uint8_t buf[MAXLEN+20], *b;
+  uint32_t len;
+  uint8_t q[] = "This is the time for all good men to come to the aid of their country...";
+  uint32_t h;
+  uint8_t qq[] = "xThis is the time for all good men to come to the aid of their country...";
+  uint32_t i;
+  uint8_t qqq[] = "xxThis is the time for all good men to come to the aid of their country...";
+  uint32_t j;
+  uint8_t qqqq[] = "xxxThis is the time for all good men to come to the aid of their country...";
+  uint32_t ref,x,y;
+  uint8_t *p;
+
+  printf("Endianness.  These lines should all be the same (for values filled in):\n");
+  printf("%.8x                            %.8x                            %.8x\n",
+         hash_word((const uint32_t *)q, (sizeof(q)-1)/4, 13),
+         hash_word((const uint32_t *)q, (sizeof(q)-5)/4, 13),
+         hash_word((const uint32_t *)q, (sizeof(q)-9)/4, 13));
+  p = q;
+  printf("%.8x %.8x %.8x %.8x %.8x %.8x %.8x %.8x %.8x %.8x %.8x %.8x\n",
+         hashlittle(p, sizeof(q)-1, 13), hashlittle(p, sizeof(q)-2, 13),
+         hashlittle(p, sizeof(q)-3, 13), hashlittle(p, sizeof(q)-4, 13),
+         hashlittle(p, sizeof(q)-5, 13), hashlittle(p, sizeof(q)-6, 13),
+         hashlittle(p, sizeof(q)-7, 13), hashlittle(p, sizeof(q)-8, 13),
+         hashlittle(p, sizeof(q)-9, 13), hashlittle(p, sizeof(q)-10, 13),
+         hashlittle(p, sizeof(q)-11, 13), hashlittle(p, sizeof(q)-12, 13));
+  p = &qq[1];
+  printf("%.8x %.8x %.8x %.8x %.8x %.8x %.8x %.8x %.8x %.8x %.8x %.8x\n",
+         hashlittle(p, sizeof(q)-1, 13), hashlittle(p, sizeof(q)-2, 13),
+         hashlittle(p, sizeof(q)-3, 13), hashlittle(p, sizeof(q)-4, 13),
+         hashlittle(p, sizeof(q)-5, 13), hashlittle(p, sizeof(q)-6, 13),
+         hashlittle(p, sizeof(q)-7, 13), hashlittle(p, sizeof(q)-8, 13),
+         hashlittle(p, sizeof(q)-9, 13), hashlittle(p, sizeof(q)-10, 13),
+         hashlittle(p, sizeof(q)-11, 13), hashlittle(p, sizeof(q)-12, 13));
+  p = &qqq[2];
+  printf("%.8x %.8x %.8x %.8x %.8x %.8x %.8x %.8x %.8x %.8x %.8x %.8x\n",
+         hashlittle(p, sizeof(q)-1, 13), hashlittle(p, sizeof(q)-2, 13),
+         hashlittle(p, sizeof(q)-3, 13), hashlittle(p, sizeof(q)-4, 13),
+         hashlittle(p, sizeof(q)-5, 13), hashlittle(p, sizeof(q)-6, 13),
+         hashlittle(p, sizeof(q)-7, 13), hashlittle(p, sizeof(q)-8, 13),
+         hashlittle(p, sizeof(q)-9, 13), hashlittle(p, sizeof(q)-10, 13),
+         hashlittle(p, sizeof(q)-11, 13), hashlittle(p, sizeof(q)-12, 13));
+  p = &qqqq[3];
+  printf("%.8x %.8x %.8x %.8x %.8x %.8x %.8x %.8x %.8x %.8x %.8x %.8x\n",
+         hashlittle(p, sizeof(q)-1, 13), hashlittle(p, sizeof(q)-2, 13),
+         hashlittle(p, sizeof(q)-3, 13), hashlittle(p, sizeof(q)-4, 13),
+         hashlittle(p, sizeof(q)-5, 13), hashlittle(p, sizeof(q)-6, 13),
+         hashlittle(p, sizeof(q)-7, 13), hashlittle(p, sizeof(q)-8, 13),
+         hashlittle(p, sizeof(q)-9, 13), hashlittle(p, sizeof(q)-10, 13),
+         hashlittle(p, sizeof(q)-11, 13), hashlittle(p, sizeof(q)-12, 13));
+  printf("\n");
+
+  /* check that hashlittle2 and hashlittle produce the same results */
+  i=47; j=0;
+  hashlittle2(q, sizeof(q), &i, &j);
+  if (hashlittle(q, sizeof(q), 47) != i)
+    printf("hashlittle2 and hashlittle mismatch\n");
+
+  /* check that hash_word2 and hash_word produce the same results */
+  len = 0xdeadbeef;
+  i=47, j=0;
+  hash_word2(&len, 1, &i, &j);
+  if (hash_word(&len, 1, 47) != i)
+    printf("hash_word2 and hash_word mismatch %x %x\n",
+	   i, hash_word(&len, 1, 47));
+
+  /* check hashlittle doesn't read before or after the ends of the string */
+  for (h=0, b=buf+1; h<8; ++h, ++b)
+  {
+    for (i=0; i<MAXLEN; ++i)
+    {
+      len = i;
+      for (j=0; j<i; ++j) *(b+j)=0;
+
+      /* these should all be equal */
+      ref = hashlittle(b, len, (uint32_t)1);
+      *(b+i)=(uint8_t)~0;
+      *(b-1)=(uint8_t)~0;
+      x = hashlittle(b, len, (uint32_t)1);
+      y = hashlittle(b, len, (uint32_t)1);
+      if ((ref != x) || (ref != y))
+      {
+	printf("alignment error: %.8x %.8x %.8x %d %d\n",ref,x,y,
+               h, i);
+      }
+    }
+  }
+}
+
+/* check for problems with nulls */
+ void driver4()
+{
+  uint8_t buf[1];
+  uint32_t h,i,state[HASHSTATE];
+
+
+  buf[0] = ~0;
+  for (i=0; i<HASHSTATE; ++i) state[i] = 1;
+  printf("These should all be different\n");
+  for (i=0, h=0; i<8; ++i)
+  {
+    h = hashlittle(buf, 0, h);
+    printf("%2ld  0-byte strings, hash is  %.8x\n", i, h);
+  }
+}
+
+
+int main()
+{
+  driver1();   /* test that the key is hashed: used for timings */
+  driver2();   /* test that whole key is hashed thoroughly */
+  driver3();   /* test that nothing but the key is hashed */
+  driver4();   /* test hashing multiple buffers (all buffers are null) */
+  return 1;
+}
+
+#endif  /* SELF_TEST */
diff --git a/lib/ccan/hash/hash.h b/lib/ccan/hash/hash.h
new file mode 100644
index 0000000000..5025c0d748
--- /dev/null
+++ b/lib/ccan/hash/hash.h
@@ -0,0 +1,312 @@
+#ifndef CCAN_HASH_H
+#define CCAN_HASH_H
+#include "config.h"
+#include <stdint.h>
+#include <stdlib.h>
+#include <ccan/build_assert/build_assert.h>
+
+/* Stolen mostly from: lookup3.c, by Bob Jenkins, May 2006, Public Domain.
+ *
+ * http://burtleburtle.net/bob/c/lookup3.c
+ */
+
+/**
+ * hash - fast hash of an array for internal use
+ * @p: the array or pointer to first element
+ * @num: the number of elements to hash
+ * @base: the base number to roll into the hash (usually 0)
+ *
+ * The memory region pointed to by p is combined with the base to form
+ * a 32-bit hash.
+ *
+ * This hash will have different results on different machines, so is
+ * only useful for internal hashes (ie. not hashes sent across the
+ * network or saved to disk).
+ *
+ * It may also change with future versions: it could even detect at runtime
+ * what the fastest hash to use is.
+ *
+ * See also: hash64, hash_stable.
+ *
+ * Example:
+ *	#include <ccan/hash/hash.h>
+ *	#include <err.h>
+ *	#include <stdio.h>
+ *	#include <string.h>
+ *
+ *	// Simple demonstration: idential strings will have the same hash, but
+ *	// two different strings will probably not.
+ *	int main(int argc, char *argv[])
+ *	{
+ *		uint32_t hash1, hash2;
+ *
+ *		if (argc != 3)
+ *			err(1, "Usage: %s <string1> <string2>", argv[0]);
+ *
+ *		hash1 = hash(argv[1], strlen(argv[1]), 0);
+ *		hash2 = hash(argv[2], strlen(argv[2]), 0);
+ *		printf("Hash is %s\n", hash1 == hash2 ? "same" : "different");
+ *		return 0;
+ *	}
+ */
+#define hash(p, num, base) hash_any((p), (num)*sizeof(*(p)), (base))
+
+/**
+ * hash_stable - hash of an array for external use
+ * @p: the array or pointer to first element
+ * @num: the number of elements to hash
+ * @base: the base number to roll into the hash (usually 0)
+ *
+ * The array of simple integer types pointed to by p is combined with
+ * the base to form a 32-bit hash.
+ *
+ * This hash will have the same results on different machines, so can
+ * be used for external hashes (ie. hashes sent across the network or
+ * saved to disk).  The results will not change in future versions of
+ * this module.
+ *
+ * Note that it is only legal to hand an array of simple integer types
+ * to this hash (ie. char, uint16_t, int64_t, etc).  In these cases,
+ * the same values will have the same hash result, even though the
+ * memory representations of integers depend on the machine
+ * endianness.
+ *
+ * See also:
+ *	hash64_stable
+ *
+ * Example:
+ *	#include <ccan/hash/hash.h>
+ *	#include <err.h>
+ *	#include <stdio.h>
+ *	#include <string.h>
+ *
+ *	int main(int argc, char *argv[])
+ *	{
+ *		if (argc != 2)
+ *			err(1, "Usage: %s <string-to-hash>", argv[0]);
+ *
+ *		printf("Hash stable result is %u\n",
+ *		       hash_stable(argv[1], strlen(argv[1]), 0));
+ *		return 0;
+ *	}
+ */
+#define hash_stable(p, num, base)					\
+	(BUILD_ASSERT_OR_ZERO(sizeof(*(p)) == 8 || sizeof(*(p)) == 4	\
+			      || sizeof(*(p)) == 2 || sizeof(*(p)) == 1) + \
+	 sizeof(*(p)) == 8 ? hash_stable_64((p), (num), (base))		\
+	 : sizeof(*(p)) == 4 ? hash_stable_32((p), (num), (base))	\
+	 : sizeof(*(p)) == 2 ? hash_stable_16((p), (num), (base))	\
+	 : hash_stable_8((p), (num), (base)))
+
+/**
+ * hash_u32 - fast hash an array of 32-bit values for internal use
+ * @key: the array of uint32_t
+ * @num: the number of elements to hash
+ * @base: the base number to roll into the hash (usually 0)
+ *
+ * The array of uint32_t pointed to by @key is combined with the base
+ * to form a 32-bit hash.  This is 2-3 times faster than hash() on small
+ * arrays, but the advantage vanishes over large hashes.
+ *
+ * This hash will have different results on different machines, so is
+ * only useful for internal hashes (ie. not hashes sent across the
+ * network or saved to disk).
+ */
+uint32_t hash_u32(const uint32_t *key, size_t num, uint32_t base);
+
+/**
+ * hash_string - very fast hash of an ascii string
+ * @str: the nul-terminated string
+ *
+ * The string is hashed, using a hash function optimized for ASCII and
+ * similar strings.  It's weaker than the other hash functions.
+ *
+ * This hash may have different results on different machines, so is
+ * only useful for internal hashes (ie. not hashes sent across the
+ * network or saved to disk).  The results will be different from the
+ * other hash functions in this module, too.
+ */
+static inline uint32_t hash_string(const char *string)
+{
+	/* This is Karl Nelson <kenelson@ece.ucdavis.edu>'s X31 hash.
+	 * It's a little faster than the (much better) lookup3 hash(): 56ns vs
+	 * 84ns on my 2GHz Intel Core Duo 2 laptop for a 10 char string. */
+	uint32_t ret;
+
+	for (ret = 0; *string; string++)
+		ret = (ret << 5) - ret + *string;
+
+	return ret;
+}
+
+/**
+ * hash64 - fast 64-bit hash of an array for internal use
+ * @p: the array or pointer to first element
+ * @num: the number of elements to hash
+ * @base: the 64-bit base number to roll into the hash (usually 0)
+ *
+ * The memory region pointed to by p is combined with the base to form
+ * a 64-bit hash.
+ *
+ * This hash will have different results on different machines, so is
+ * only useful for internal hashes (ie. not hashes sent across the
+ * network or saved to disk).
+ *
+ * It may also change with future versions: it could even detect at runtime
+ * what the fastest hash to use is.
+ *
+ * See also: hash.
+ *
+ * Example:
+ *	#include <ccan/hash/hash.h>
+ *	#include <err.h>
+ *	#include <stdio.h>
+ *	#include <string.h>
+ *
+ *	// Simple demonstration: idential strings will have the same hash, but
+ *	// two different strings will probably not.
+ *	int main(int argc, char *argv[])
+ *	{
+ *		uint64_t hash1, hash2;
+ *
+ *		if (argc != 3)
+ *			err(1, "Usage: %s <string1> <string2>", argv[0]);
+ *
+ *		hash1 = hash64(argv[1], strlen(argv[1]), 0);
+ *		hash2 = hash64(argv[2], strlen(argv[2]), 0);
+ *		printf("Hash is %s\n", hash1 == hash2 ? "same" : "different");
+ *		return 0;
+ *	}
+ */
+#define hash64(p, num, base) hash64_any((p), (num)*sizeof(*(p)), (base))
+
+/**
+ * hash64_stable - 64 bit hash of an array for external use
+ * @p: the array or pointer to first element
+ * @num: the number of elements to hash
+ * @base: the base number to roll into the hash (usually 0)
+ *
+ * The array of simple integer types pointed to by p is combined with
+ * the base to form a 64-bit hash.
+ *
+ * This hash will have the same results on different machines, so can
+ * be used for external hashes (ie. hashes sent across the network or
+ * saved to disk).  The results will not change in future versions of
+ * this module.
+ *
+ * Note that it is only legal to hand an array of simple integer types
+ * to this hash (ie. char, uint16_t, int64_t, etc).  In these cases,
+ * the same values will have the same hash result, even though the
+ * memory representations of integers depend on the machine
+ * endianness.
+ *
+ * See also:
+ *	hash_stable
+ *
+ * Example:
+ *	#include <ccan/hash/hash.h>
+ *	#include <err.h>
+ *	#include <stdio.h>
+ *	#include <string.h>
+ *
+ *	int main(int argc, char *argv[])
+ *	{
+ *		if (argc != 2)
+ *			err(1, "Usage: %s <string-to-hash>", argv[0]);
+ *
+ *		printf("Hash stable result is %llu\n",
+ *		       (long long)hash64_stable(argv[1], strlen(argv[1]), 0));
+ *		return 0;
+ *	}
+ */
+#define hash64_stable(p, num, base)					\
+	(BUILD_ASSERT_OR_ZERO(sizeof(*(p)) == 8 || sizeof(*(p)) == 4	\
+			      || sizeof(*(p)) == 2 || sizeof(*(p)) == 1) + \
+	 sizeof(*(p)) == 8 ? hash64_stable_64((p), (num), (base))	\
+	 : sizeof(*(p)) == 4 ? hash64_stable_32((p), (num), (base))	\
+	 : sizeof(*(p)) == 2 ? hash64_stable_16((p), (num), (base))	\
+	 : hash64_stable_8((p), (num), (base)))
+
+
+/**
+ * hashl - fast 32/64-bit hash of an array for internal use
+ * @p: the array or pointer to first element
+ * @num: the number of elements to hash
+ * @base: the base number to roll into the hash (usually 0)
+ *
+ * This is either hash() or hash64(), on 32/64 bit long machines.
+ */
+#define hashl(p, num, base)						\
+	(BUILD_ASSERT_OR_ZERO(sizeof(long) == sizeof(uint32_t)		\
+			      || sizeof(long) == sizeof(uint64_t)) +	\
+	(sizeof(long) == sizeof(uint64_t)				\
+	 ? hash64((p), (num), (base)) : hash((p), (num), (base))))
+
+/* Our underlying operations. */
+uint32_t hash_any(const void *key, size_t length, uint32_t base);
+uint32_t hash_stable_64(const void *key, size_t n, uint32_t base);
+uint32_t hash_stable_32(const void *key, size_t n, uint32_t base);
+uint32_t hash_stable_16(const void *key, size_t n, uint32_t base);
+uint32_t hash_stable_8(const void *key, size_t n, uint32_t base);
+uint64_t hash64_any(const void *key, size_t length, uint64_t base);
+uint64_t hash64_stable_64(const void *key, size_t n, uint64_t base);
+uint64_t hash64_stable_32(const void *key, size_t n, uint64_t base);
+uint64_t hash64_stable_16(const void *key, size_t n, uint64_t base);
+uint64_t hash64_stable_8(const void *key, size_t n, uint64_t base);
+
+/**
+ * hash_pointer - hash a pointer for internal use
+ * @p: the pointer value to hash
+ * @base: the base number to roll into the hash (usually 0)
+ *
+ * The pointer p (not what p points to!) is combined with the base to form
+ * a 32-bit hash.
+ *
+ * This hash will have different results on different machines, so is
+ * only useful for internal hashes (ie. not hashes sent across the
+ * network or saved to disk).
+ *
+ * Example:
+ *	#include <ccan/hash/hash.h>
+ *
+ *	// Code to keep track of memory regions.
+ *	struct region {
+ *		struct region *chain;
+ *		void *start;
+ *		unsigned int size;
+ *	};
+ *	// We keep a simple hash table.
+ *	static struct region *region_hash[128];
+ *
+ *	static void add_region(struct region *r)
+ *	{
+ *		unsigned int h = hash_pointer(r->start, 0);
+ *
+ *		r->chain = region_hash[h];
+ *		region_hash[h] = r->chain;
+ *	}
+ *
+ *	static struct region *find_region(const void *start)
+ *	{
+ *		struct region *r;
+ *
+ *		for (r = region_hash[hash_pointer(start, 0)]; r; r = r->chain)
+ *			if (r->start == start)
+ *				return r;
+ *		return NULL;
+ *	}
+ */
+static inline uint32_t hash_pointer(const void *p, uint32_t base)
+{
+	if (sizeof(p) % sizeof(uint32_t) == 0) {
+		/* This convoluted union is the right way of aliasing. */
+		union {
+			uint32_t u32[sizeof(p) / sizeof(uint32_t)];
+			const void *p;
+		} u;
+		u.p = p;
+		return hash_u32(u.u32, sizeof(p) / sizeof(uint32_t), base);
+	} else
+		return hash(&p, 1, base);
+}
+#endif /* HASH_H */
diff --git a/lib/ccan/hash/test/api-hash_stable.c b/lib/ccan/hash/test/api-hash_stable.c
new file mode 100644
index 0000000000..bb58d16b18
--- /dev/null
+++ b/lib/ccan/hash/test/api-hash_stable.c
@@ -0,0 +1,300 @@
+#include <ccan/hash/hash.h>
+#include <ccan/tap/tap.h>
+#include <stdbool.h>
+#include <string.h>
+
+#define ARRAY_WORDS 5
+
+int main(int argc, char *argv[])
+{
+	unsigned int i;
+	uint8_t u8array[ARRAY_WORDS];
+	uint16_t u16array[ARRAY_WORDS];
+	uint32_t u32array[ARRAY_WORDS];
+	uint64_t u64array[ARRAY_WORDS];
+
+	/* Initialize arrays. */
+	for (i = 0; i < ARRAY_WORDS; i++) {
+		u8array[i] = i;
+		u16array[i] = i;
+		u32array[i] = i;
+		u64array[i] = i;
+	}
+
+	plan_tests(264);
+
+	/* hash_stable is API-guaranteed. */
+	ok1(hash_stable(u8array, ARRAY_WORDS, 0) == 0x1d4833cc);
+	ok1(hash_stable(u8array, ARRAY_WORDS, 1) == 0x37125e2 );
+	ok1(hash_stable(u8array, ARRAY_WORDS, 2) == 0x330a007a);
+	ok1(hash_stable(u8array, ARRAY_WORDS, 4) == 0x7b0df29b);
+	ok1(hash_stable(u8array, ARRAY_WORDS, 8) == 0xe7e5d741);
+	ok1(hash_stable(u8array, ARRAY_WORDS, 16) == 0xaae57471);
+	ok1(hash_stable(u8array, ARRAY_WORDS, 32) == 0xc55399e5);
+	ok1(hash_stable(u8array, ARRAY_WORDS, 64) == 0x67f21f7 );
+	ok1(hash_stable(u8array, ARRAY_WORDS, 128) == 0x1d795b71);
+	ok1(hash_stable(u8array, ARRAY_WORDS, 256) == 0xeb961671);
+	ok1(hash_stable(u8array, ARRAY_WORDS, 512) == 0xc2597247);
+	ok1(hash_stable(u8array, ARRAY_WORDS, 1024) == 0x3f5c4d75);
+	ok1(hash_stable(u8array, ARRAY_WORDS, 2048) == 0xe65cf4f9);
+	ok1(hash_stable(u8array, ARRAY_WORDS, 4096) == 0xf2cd06cb);
+	ok1(hash_stable(u8array, ARRAY_WORDS, 8192) == 0x443041e1);
+	ok1(hash_stable(u8array, ARRAY_WORDS, 16384) == 0xdfc618f5);
+	ok1(hash_stable(u8array, ARRAY_WORDS, 32768) == 0x5e3d5b97);
+	ok1(hash_stable(u8array, ARRAY_WORDS, 65536) == 0xd5f64730);
+	ok1(hash_stable(u8array, ARRAY_WORDS, 131072) == 0x372bbecc);
+	ok1(hash_stable(u8array, ARRAY_WORDS, 262144) == 0x7c194c8d);
+	ok1(hash_stable(u8array, ARRAY_WORDS, 524288) == 0x16cbb416);
+	ok1(hash_stable(u8array, ARRAY_WORDS, 1048576) == 0x53e99222);
+	ok1(hash_stable(u8array, ARRAY_WORDS, 2097152) == 0x6394554a);
+	ok1(hash_stable(u8array, ARRAY_WORDS, 4194304) == 0xd83a506d);
+	ok1(hash_stable(u8array, ARRAY_WORDS, 8388608) == 0x7619d9a4);
+	ok1(hash_stable(u8array, ARRAY_WORDS, 16777216) == 0xfe98e5f6);
+	ok1(hash_stable(u8array, ARRAY_WORDS, 33554432) == 0x6c262927);
+	ok1(hash_stable(u8array, ARRAY_WORDS, 67108864) == 0x3f0106fd);
+	ok1(hash_stable(u8array, ARRAY_WORDS, 134217728) == 0xc91e3a28);
+	ok1(hash_stable(u8array, ARRAY_WORDS, 268435456) == 0x14229579);
+	ok1(hash_stable(u8array, ARRAY_WORDS, 536870912) == 0x9dbefa76);
+	ok1(hash_stable(u8array, ARRAY_WORDS, 1073741824) == 0xb05c0c78);
+	ok1(hash_stable(u8array, ARRAY_WORDS, 2147483648U) == 0x88f24d81);
+
+	ok1(hash_stable(u16array, ARRAY_WORDS, 0) == 0xecb5f507);
+	ok1(hash_stable(u16array, ARRAY_WORDS, 1) == 0xadd666e6);
+	ok1(hash_stable(u16array, ARRAY_WORDS, 2) == 0xea0f214c);
+	ok1(hash_stable(u16array, ARRAY_WORDS, 4) == 0xae4051ba);
+	ok1(hash_stable(u16array, ARRAY_WORDS, 8) == 0x6ed28026);
+	ok1(hash_stable(u16array, ARRAY_WORDS, 16) == 0xa3917a19);
+	ok1(hash_stable(u16array, ARRAY_WORDS, 32) == 0xf370f32b);
+	ok1(hash_stable(u16array, ARRAY_WORDS, 64) == 0x807af460);
+	ok1(hash_stable(u16array, ARRAY_WORDS, 128) == 0xb4c8cd83);
+	ok1(hash_stable(u16array, ARRAY_WORDS, 256) == 0xa10cb5b0);
+	ok1(hash_stable(u16array, ARRAY_WORDS, 512) == 0x8b7d7387);
+	ok1(hash_stable(u16array, ARRAY_WORDS, 1024) == 0x9e49d1c );
+	ok1(hash_stable(u16array, ARRAY_WORDS, 2048) == 0x288830d1);
+	ok1(hash_stable(u16array, ARRAY_WORDS, 4096) == 0xbe078a43);
+	ok1(hash_stable(u16array, ARRAY_WORDS, 8192) == 0xa16d5d88);
+	ok1(hash_stable(u16array, ARRAY_WORDS, 16384) == 0x46839fcd);
+	ok1(hash_stable(u16array, ARRAY_WORDS, 32768) == 0x9db9bd4f);
+	ok1(hash_stable(u16array, ARRAY_WORDS, 65536) == 0xedff58f8);
+	ok1(hash_stable(u16array, ARRAY_WORDS, 131072) == 0x95ecef18);
+	ok1(hash_stable(u16array, ARRAY_WORDS, 262144) == 0x23c31b7d);
+	ok1(hash_stable(u16array, ARRAY_WORDS, 524288) == 0x1d85c7d0);
+	ok1(hash_stable(u16array, ARRAY_WORDS, 1048576) == 0x25218842);
+	ok1(hash_stable(u16array, ARRAY_WORDS, 2097152) == 0x711d985c);
+	ok1(hash_stable(u16array, ARRAY_WORDS, 4194304) == 0x85470eca);
+	ok1(hash_stable(u16array, ARRAY_WORDS, 8388608) == 0x99ed4ceb);
+	ok1(hash_stable(u16array, ARRAY_WORDS, 16777216) == 0x67b3710c);
+	ok1(hash_stable(u16array, ARRAY_WORDS, 33554432) == 0x77f1ab35);
+	ok1(hash_stable(u16array, ARRAY_WORDS, 67108864) == 0x81f688aa);
+	ok1(hash_stable(u16array, ARRAY_WORDS, 134217728) == 0x27b56ca5);
+	ok1(hash_stable(u16array, ARRAY_WORDS, 268435456) == 0xf21ba203);
+	ok1(hash_stable(u16array, ARRAY_WORDS, 536870912) == 0xd48d1d1 );
+	ok1(hash_stable(u16array, ARRAY_WORDS, 1073741824) == 0xa542b62d);
+	ok1(hash_stable(u16array, ARRAY_WORDS, 2147483648U) == 0xa04c7058);
+
+	ok1(hash_stable(u32array, ARRAY_WORDS, 0) == 0x13305f8c);
+	ok1(hash_stable(u32array, ARRAY_WORDS, 1) == 0x171abf74);
+	ok1(hash_stable(u32array, ARRAY_WORDS, 2) == 0x7646fcc7);
+	ok1(hash_stable(u32array, ARRAY_WORDS, 4) == 0xa758ed5);
+	ok1(hash_stable(u32array, ARRAY_WORDS, 8) == 0x2dedc2e4);
+	ok1(hash_stable(u32array, ARRAY_WORDS, 16) == 0x28e2076b);
+	ok1(hash_stable(u32array, ARRAY_WORDS, 32) == 0xb73091c5);
+	ok1(hash_stable(u32array, ARRAY_WORDS, 64) == 0x87daf5db);
+	ok1(hash_stable(u32array, ARRAY_WORDS, 128) == 0xa16dfe20);
+	ok1(hash_stable(u32array, ARRAY_WORDS, 256) == 0x300c63c3);
+	ok1(hash_stable(u32array, ARRAY_WORDS, 512) == 0x255c91fc);
+	ok1(hash_stable(u32array, ARRAY_WORDS, 1024) == 0x6357b26);
+	ok1(hash_stable(u32array, ARRAY_WORDS, 2048) == 0x4bc5f339);
+	ok1(hash_stable(u32array, ARRAY_WORDS, 4096) == 0x1301617c);
+	ok1(hash_stable(u32array, ARRAY_WORDS, 8192) == 0x506792c9);
+	ok1(hash_stable(u32array, ARRAY_WORDS, 16384) == 0xcd596705);
+	ok1(hash_stable(u32array, ARRAY_WORDS, 32768) == 0xa8713cac);
+	ok1(hash_stable(u32array, ARRAY_WORDS, 65536) == 0x94d9794);
+	ok1(hash_stable(u32array, ARRAY_WORDS, 131072) == 0xac753e8);
+	ok1(hash_stable(u32array, ARRAY_WORDS, 262144) == 0xcd8bdd20);
+	ok1(hash_stable(u32array, ARRAY_WORDS, 524288) == 0xd44faf80);
+	ok1(hash_stable(u32array, ARRAY_WORDS, 1048576) == 0x2547ccbe);
+	ok1(hash_stable(u32array, ARRAY_WORDS, 2097152) == 0xbab06dbc);
+	ok1(hash_stable(u32array, ARRAY_WORDS, 4194304) == 0xaac0e882);
+	ok1(hash_stable(u32array, ARRAY_WORDS, 8388608) == 0x443f48d0);
+	ok1(hash_stable(u32array, ARRAY_WORDS, 16777216) == 0xdff49fcc);
+	ok1(hash_stable(u32array, ARRAY_WORDS, 33554432) == 0x9ce0fd65);
+	ok1(hash_stable(u32array, ARRAY_WORDS, 67108864) == 0x9ddb1def);
+	ok1(hash_stable(u32array, ARRAY_WORDS, 134217728) == 0x86096f25);
+	ok1(hash_stable(u32array, ARRAY_WORDS, 268435456) == 0xe713b7b5);
+	ok1(hash_stable(u32array, ARRAY_WORDS, 536870912) == 0x5baeffc5);
+	ok1(hash_stable(u32array, ARRAY_WORDS, 1073741824) == 0xde874f52);
+	ok1(hash_stable(u32array, ARRAY_WORDS, 2147483648U) == 0xeca13b4e);
+
+	ok1(hash_stable(u64array, ARRAY_WORDS, 0) == 0x12ef6302);
+	ok1(hash_stable(u64array, ARRAY_WORDS, 1) == 0xe9aeb406);
+	ok1(hash_stable(u64array, ARRAY_WORDS, 2) == 0xc4218ceb);
+	ok1(hash_stable(u64array, ARRAY_WORDS, 4) == 0xb3d11412);
+	ok1(hash_stable(u64array, ARRAY_WORDS, 8) == 0xdafbd654);
+	ok1(hash_stable(u64array, ARRAY_WORDS, 16) == 0x9c336cba);
+	ok1(hash_stable(u64array, ARRAY_WORDS, 32) == 0x65059721);
+	ok1(hash_stable(u64array, ARRAY_WORDS, 64) == 0x95b5bbe6);
+	ok1(hash_stable(u64array, ARRAY_WORDS, 128) == 0xe7596b84);
+	ok1(hash_stable(u64array, ARRAY_WORDS, 256) == 0x503622a2);
+	ok1(hash_stable(u64array, ARRAY_WORDS, 512) == 0xecdcc5ca);
+	ok1(hash_stable(u64array, ARRAY_WORDS, 1024) == 0xc40d0513);
+	ok1(hash_stable(u64array, ARRAY_WORDS, 2048) == 0xaab25e4d);
+	ok1(hash_stable(u64array, ARRAY_WORDS, 4096) == 0xcc353fb9);
+	ok1(hash_stable(u64array, ARRAY_WORDS, 8192) == 0x18e2319f);
+	ok1(hash_stable(u64array, ARRAY_WORDS, 16384) == 0xfddaae8d);
+	ok1(hash_stable(u64array, ARRAY_WORDS, 32768) == 0xef7976f2);
+	ok1(hash_stable(u64array, ARRAY_WORDS, 65536) == 0x86359fc9);
+	ok1(hash_stable(u64array, ARRAY_WORDS, 131072) == 0x8b5af385);
+	ok1(hash_stable(u64array, ARRAY_WORDS, 262144) == 0x80d4ee31);
+	ok1(hash_stable(u64array, ARRAY_WORDS, 524288) == 0x42f5f85b);
+	ok1(hash_stable(u64array, ARRAY_WORDS, 1048576) == 0x9a6920e1);
+	ok1(hash_stable(u64array, ARRAY_WORDS, 2097152) == 0x7b7c9850);
+	ok1(hash_stable(u64array, ARRAY_WORDS, 4194304) == 0x69573e09);
+	ok1(hash_stable(u64array, ARRAY_WORDS, 8388608) == 0xc942bc0e);
+	ok1(hash_stable(u64array, ARRAY_WORDS, 16777216) == 0x7a89f0f1);
+	ok1(hash_stable(u64array, ARRAY_WORDS, 33554432) == 0x2dd641ca);
+	ok1(hash_stable(u64array, ARRAY_WORDS, 67108864) == 0x89bbd391);
+	ok1(hash_stable(u64array, ARRAY_WORDS, 134217728) == 0xbcf88e31);
+	ok1(hash_stable(u64array, ARRAY_WORDS, 268435456) == 0xfa7a3460);
+	ok1(hash_stable(u64array, ARRAY_WORDS, 536870912) == 0x49a37be0);
+	ok1(hash_stable(u64array, ARRAY_WORDS, 1073741824) == 0x1b346394);
+	ok1(hash_stable(u64array, ARRAY_WORDS, 2147483648U) == 0x6c3a1592);
+
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 0) == 16887282882572727244ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 1) == 12032777473133454818ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 2) == 18183407363221487738ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 4) == 17860764172704150171ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 8) == 18076051600675559233ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 16) == 9909361918431556721ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 32) == 12937969888744675813ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 64) == 5245669057381736951ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 128) == 4376874646406519665ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 256) == 14219974419871569521ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 512) == 2263415354134458951ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 1024) == 4953859694526221685ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 2048) == 3432228642067641593ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 4096) == 1219647244417697483ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 8192) == 7629939424585859553ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 16384) == 10041660531376789749ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 32768) == 13859885793922603927ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 65536) == 15069060338344675120ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 131072) == 818163430835601100ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 262144) == 14914314323019517069ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 524288) == 17518437749769352214ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 1048576) == 14920048004901212706ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 2097152) == 8758567366332536138ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 4194304) == 6226655736088907885ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 8388608) == 13716650013685832100ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 16777216) == 305325651636315638ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 33554432) == 16784147606583781671ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 67108864) == 16509467555140798205ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 134217728) == 8717281234694060584ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 268435456) == 8098476701725660537ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 536870912) == 16345871539461094006ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 1073741824) == 3755557000429964408ULL);
+	ok1(hash64_stable(u8array, ARRAY_WORDS, 2147483648U) == 15017348801959710081ULL);
+
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 0) == 1038028831307724039ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 1) == 10155473272642627302ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 2) == 5714751190106841420ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 4) == 3923885607767527866ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 8) == 3931017318293995558ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 16) == 1469696588339313177ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 32) == 11522218526952715051ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 64) == 6953517591561958496ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 128) == 7406689491740052867ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 256) == 10101844489704093104ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 512) == 12511348870707245959ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 1024) == 1614019938016861468ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 2048) == 5294796182374592721ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 4096) == 16089570706643716675ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 8192) == 1689302638424579464ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 16384) == 1446340172370386893ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 32768) == 16535503506744393039ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 65536) == 3496794142527150328ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 131072) == 6568245367474548504ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 262144) == 9487676460765485949ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 524288) == 4519762130966530000ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 1048576) == 15623412069215340610ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 2097152) == 544013388676438108ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 4194304) == 5594904760290840266ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 8388608) == 18098755780041592043ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 16777216) == 6389168672387330316ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 33554432) == 896986127732419381ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 67108864) == 13232626471143901354ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 134217728) == 53378562890493093ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 268435456) == 10072361400297824771ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 536870912) == 14511948118285144529ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 1073741824) == 6981033484844447277ULL);
+	ok1(hash64_stable(u16array, ARRAY_WORDS, 2147483648U) == 5619339091684126808ULL);
+
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 0) == 3037571077312110476ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 1) == 14732398743825071988ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 2) == 14949132158206672071ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 4) == 1291370080511561429ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 8) == 10792665964172133092ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 16) == 14250138032054339435ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 32) == 17136741522078732741ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 64) == 3260193403318236635ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 128) == 10526616652205653536ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 256) == 9019690373358576579ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 512) == 6997491436599677436ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 1024) == 18302783371416533798ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 2048) == 10149320644446516025ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 4096) == 7073759949410623868ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 8192) == 17442399482223760073ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 16384) == 2983906194216281861ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 32768) == 4975845419129060524ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 65536) == 594019910205413268ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 131072) == 11903010186073691112ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 262144) == 7339636527154847008ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 524288) == 15243305400579108736ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 1048576) == 16737926245392043198ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 2097152) == 15725083267699862972ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 4194304) == 12527834265678833794ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 8388608) == 13908436455987824848ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 16777216) == 9672773345173872588ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 33554432) == 2305314279896710501ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 67108864) == 1866733780381408751ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 134217728) == 11906263969465724709ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 268435456) == 5501594918093830069ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 536870912) == 15823785789276225477ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 1073741824) == 17353000723889475410ULL);
+	ok1(hash64_stable(u32array, ARRAY_WORDS, 2147483648U) == 7494736910655503182ULL);
+
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 0) == 9765419389786481410ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 1) == 11182806172127114246ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 2) == 2559155171395472619ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 4) == 3311692033324815378ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 8) == 1297175419505333844ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 16) == 617896928653569210ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 32) == 1517398559958603553ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 64) == 4504821917445110758ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 128) == 1971743331114904452ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 256) == 6177667912354374306ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 512) == 15570521289777792458ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 1024) == 9204559632415917331ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 2048) == 9008982669760028237ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 4096) == 14803537660281700281ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 8192) == 2873966517448487327ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 16384) == 5859277625928363661ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 32768) == 15520461285618185970ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 65536) == 16746489793331175369ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 131072) == 514952025484227461ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 262144) == 10867212269810675249ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 524288) == 9822204377278314587ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 1048576) == 3295088921987850465ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 2097152) == 7559197431498053712ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 4194304) == 1667267269116771849ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 8388608) == 2916804068951374862ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 16777216) == 14422558383125688561ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 33554432) == 10083112683694342602ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 67108864) == 7222777647078298513ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 134217728) == 18424513674048212529ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 268435456) == 14913668581101810784ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 536870912) == 14377721174297902048ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 1073741824) == 6031715005667500948ULL);
+	ok1(hash64_stable(u64array, ARRAY_WORDS, 2147483648U) == 4827100319722378642ULL);
+
+	return exit_status();
+}
diff --git a/lib/ccan/hash/test/run.c b/lib/ccan/hash/test/run.c
new file mode 100644
index 0000000000..dad8e86b9e
--- /dev/null
+++ b/lib/ccan/hash/test/run.c
@@ -0,0 +1,149 @@
+#include <ccan/hash/hash.h>
+#include <ccan/tap/tap.h>
+#include <ccan/hash/hash.c>
+#include <stdbool.h>
+#include <string.h>
+
+#define ARRAY_WORDS 5
+
+int main(int argc, char *argv[])
+{
+	unsigned int i, j, k;
+	uint32_t array[ARRAY_WORDS], val;
+	char array2[sizeof(array) + sizeof(uint32_t)];
+	uint32_t results[256];
+
+	/* Initialize array. */
+	for (i = 0; i < ARRAY_WORDS; i++)
+		array[i] = i;
+
+	plan_tests(39);
+	/* Hash should be the same, indep of memory alignment. */
+	val = hash(array, ARRAY_WORDS, 0);
+	for (i = 0; i < sizeof(uint32_t); i++) {
+		memcpy(array2 + i, array, sizeof(array));
+		ok(hash(array2 + i, ARRAY_WORDS, 0) != val,
+		   "hash matched at offset %i", i);
+	}
+
+	/* Hash of random values should have random distribution:
+	 * check one byte at a time. */
+	for (i = 0; i < sizeof(uint32_t); i++) {
+		unsigned int lowest = -1U, highest = 0;
+
+		memset(results, 0, sizeof(results));
+
+		for (j = 0; j < 256000; j++) {
+			for (k = 0; k < ARRAY_WORDS; k++)
+				array[k] = random();
+			results[(hash(array, ARRAY_WORDS, 0) >> i*8)&0xFF]++;
+		}
+
+		for (j = 0; j < 256; j++) {
+			if (results[j] < lowest)
+				lowest = results[j];
+			if (results[j] > highest)
+				highest = results[j];
+		}
+		/* Expect within 20% */
+		ok(lowest > 800, "Byte %i lowest %i", i, lowest);
+		ok(highest < 1200, "Byte %i highest %i", i, highest);
+		diag("Byte %i, range %u-%u", i, lowest, highest);
+	}
+
+	/* Hash of random values should have random distribution:
+	 * check one byte at a time. */
+	for (i = 0; i < sizeof(uint64_t); i++) {
+		unsigned int lowest = -1U, highest = 0;
+
+		memset(results, 0, sizeof(results));
+
+		for (j = 0; j < 256000; j++) {
+			for (k = 0; k < ARRAY_WORDS; k++)
+				array[k] = random();
+			results[(hash64(array, sizeof(array)/sizeof(uint64_t),
+					0) >> i*8)&0xFF]++;
+		}
+
+		for (j = 0; j < 256; j++) {
+			if (results[j] < lowest)
+				lowest = results[j];
+			if (results[j] > highest)
+				highest = results[j];
+		}
+		/* Expect within 20% */
+		ok(lowest > 800, "Byte %i lowest %i", i, lowest);
+		ok(highest < 1200, "Byte %i highest %i", i, highest);
+		diag("Byte %i, range %u-%u", i, lowest, highest);
+	}
+
+	/* Hash of pointer values should also have random distribution. */
+	for (i = 0; i < sizeof(uint32_t); i++) {
+		unsigned int lowest = -1U, highest = 0;
+		char *p = malloc(256000);
+
+		memset(results, 0, sizeof(results));
+
+		for (j = 0; j < 256000; j++)
+			results[(hash_pointer(p + j, 0) >> i*8)&0xFF]++;
+		free(p);
+
+		for (j = 0; j < 256; j++) {
+			if (results[j] < lowest)
+				lowest = results[j];
+			if (results[j] > highest)
+				highest = results[j];
+		}
+		/* Expect within 20% */
+		ok(lowest > 800, "hash_pointer byte %i lowest %i", i, lowest);
+		ok(highest < 1200, "hash_pointer byte %i highest %i",
+		   i, highest);
+		diag("hash_pointer byte %i, range %u-%u", i, lowest, highest);
+	}
+
+	if (sizeof(long) == sizeof(uint32_t))
+		ok1(hashl(array, ARRAY_WORDS, 0)
+		    == hash(array, ARRAY_WORDS, 0));
+	else
+		ok1(hashl(array, ARRAY_WORDS, 0)
+		    == hash64(array, ARRAY_WORDS, 0));
+
+	/* String hash: weak, so only test bottom byte */
+	for (i = 0; i < 1; i++) {
+		unsigned int num = 0, cursor, lowest = -1U, highest = 0;
+		char p[5];
+
+		memset(results, 0, sizeof(results));
+
+		memset(p, 'A', sizeof(p));
+		p[sizeof(p)-1] = '\0';
+
+		for (;;) {
+			for (cursor = 0; cursor < sizeof(p)-1; cursor++) {
+				p[cursor]++;
+				if (p[cursor] <= 'z')
+					break;
+				p[cursor] = 'A';
+			}
+			if (cursor == sizeof(p)-1)
+				break;
+
+			results[(hash_string(p) >> i*8)&0xFF]++;
+			num++;
+		}
+
+		for (j = 0; j < 256; j++) {
+			if (results[j] < lowest)
+				lowest = results[j];
+			if (results[j] > highest)
+				highest = results[j];
+		}
+		/* Expect within 20% */
+		ok(lowest > 35000, "hash_pointer byte %i lowest %i", i, lowest);
+		ok(highest < 53000, "hash_pointer byte %i highest %i",
+		   i, highest);
+		diag("hash_pointer byte %i, range %u-%u", i, lowest, highest);
+	}
+
+	return exit_status();
+}
diff --git a/lib/ccan/htable/LICENSE b/lib/ccan/htable/LICENSE
new file mode 100644
index 0000000000..d511905c16
--- /dev/null
+++ b/lib/ccan/htable/LICENSE
@@ -0,0 +1,339 @@
+		    GNU GENERAL PUBLIC LICENSE
+		       Version 2, June 1991
+
+ Copyright (C) 1989, 1991 Free Software Foundation, Inc.,
+ 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+			    Preamble
+
+  The licenses for most software are designed to take away your
+freedom to share and change it.  By contrast, the GNU General Public
+License is intended to guarantee your freedom to share and change free
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+Foundation's software and to any other program whose authors commit to
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+your programs, too.
+
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+
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+   TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
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+  0. This License applies to any program or other work which contains
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+running the Program is not restricted, and the output from the Program
+is covered only if its contents constitute a work based on the
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+
+You may charge a fee for the physical act of transferring a copy, and
+you may at your option offer warranty protection in exchange for a fee.
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+  2. You may modify your copy or copies of the Program or any portion
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+
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+
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+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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+    You should have received a copy of the GNU General Public License along
+    with this program; if not, write to the Free Software Foundation, Inc.,
+    51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
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+Also add information on how to contact you by electronic and paper mail.
+
+If the program is interactive, make it output a short notice like this
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+    Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    This is free software, and you are welcome to redistribute it
+    under certain conditions; type `show c' for details.
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+The hypothetical commands `show w' and `show c' should show the appropriate
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+
+  Yoyodyne, Inc., hereby disclaims all copyright interest in the program
+  `Gnomovision' (which makes passes at compilers) written by James Hacker.
+
+  <signature of Ty Coon>, 1 April 1989
+  Ty Coon, President of Vice
+
+This General Public License does not permit incorporating your program into
+proprietary programs.  If your program is a subroutine library, you may
+consider it more useful to permit linking proprietary applications with the
+library.  If this is what you want to do, use the GNU Lesser General
+Public License instead of this License.
diff --git a/lib/ccan/htable/_info b/lib/ccan/htable/_info
new file mode 100644
index 0000000000..8dabe46a50
--- /dev/null
+++ b/lib/ccan/htable/_info
@@ -0,0 +1,115 @@
+#include <string.h>
+#include <stdio.h>
+
+/**
+ * htable - hash table routines
+ *
+ * A hash table is an efficient structure for looking up keys.  This version
+ * grows with usage and allows efficient deletion.
+ *
+ * Example:
+ *	#include <ccan/htable/htable.h>
+ *	#include <ccan/hash/hash.h>
+ *	#include <stdio.h>
+ *	#include <err.h>
+ *	#include <string.h>
+ *
+ *	struct name_to_digit {
+ *		const char *name;
+ *		unsigned int val;
+ *	};
+ *
+ *	static struct name_to_digit map[] = {
+ *		{ "zero", 0},
+ *		{ "one", 1 },
+ *		{ "two", 2 },
+ *		{ "three", 3 },
+ *		{ "four", 4 },
+ *		{ "five", 5 },
+ *		{ "six", 6 },
+ *		{ "seven", 7 },
+ *		{ "eight", 8 },
+ *		{ "nine", 9 }
+ *	};
+ *
+ *	// Wrapper for rehash function pointer.
+ *	static size_t rehash(const void *e, void *unused)
+ *	{
+ *		return hash_string(((struct name_to_digit *)e)->name);
+ *	}
+ *
+ *	// Comparison function.
+ *	static bool streq(const void *e, void *string)
+ *	{
+ *		return strcmp(((struct name_to_digit *)e)->name, string) == 0;
+ *	}
+ *
+ *	// We let them add their own aliases, eg. --alias=v=5
+ *	static void add_alias(struct htable *ht, const char *alias)
+ *	{
+ *		char *eq;
+ *		struct name_to_digit *n;
+ *
+ *		n = malloc(sizeof(*n));
+ *		n->name = strdup(alias);
+ *
+ *		eq = strchr(n->name, '=');
+ *		if (!eq || ((n->val = atoi(eq+1)) == 0 && !strcmp(eq+1, "0")))
+ *			errx(1, "Usage: --alias=<name>=<value>");
+ *		*eq = '\0';
+ *		htable_add(ht, hash_string(n->name), n);
+ *	}
+ *
+ *	int main(int argc, char *argv[])
+ *	{
+ *		struct htable *ht;
+ *		unsigned int i;
+ *		unsigned long val;
+ *
+ *		if (argc < 2)
+ *			errx(1, "Usage: %s [--alias=<name>=<val>]... <str>...",
+ *			     argv[0]);
+ *
+ *		// Create and populate hash table.
+ *		ht = htable_new(rehash, NULL);
+ *		for (i = 0; i < sizeof(map)/sizeof(map[0]); i++)
+ *			htable_add(ht, hash_string(map[i].name), &map[i]);
+ *
+ *		// Add any aliases to the hash table.
+ *		for (i = 1; i < argc; i++) {
+ *			if (!strncmp(argv[i], "--alias=", strlen("--alias=")))
+ *				add_alias(ht, argv[i] + strlen("--alias="));
+ *			else
+ *				break;
+ *		}
+ *
+ *		// Find the other args in the hash table.
+ *		for (val = 0; i < argc; i++) {
+ *			struct name_to_digit *n;
+ *			n = htable_get(ht, hash_string(argv[i]),
+ *				       streq, argv[i]);
+ *			if (!n)
+ *				errx(1, "Invalid digit name %s", argv[i]);
+ *			// Append it to the value we are building up.
+ *			val *= 10;
+ *			val += n->val;
+ *		}
+ *		printf("%lu\n", val);
+ *		return 0;
+ *	}
+ *
+ * License: GPLv2 (or later)
+ * Author: Rusty Russell <rusty@rustcorp.com.au>
+ */
+int main(int argc, char *argv[])
+{
+	if (argc != 2)
+		return 1;
+
+	if (strcmp(argv[1], "depends") == 0) {
+		printf("ccan/compiler\n");
+		return 0;
+	}
+
+	return 1;
+}
diff --git a/lib/ccan/htable/htable.c b/lib/ccan/htable/htable.c
new file mode 100644
index 0000000000..a15c54d795
--- /dev/null
+++ b/lib/ccan/htable/htable.c
@@ -0,0 +1,290 @@
+#include <ccan/htable/htable.h>
+#include <ccan/compiler/compiler.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <limits.h>
+#include <stdbool.h>
+#include <assert.h>
+
+/* This means a struct htable takes at least 512 bytes / 1k (32/64 bits). */
+#define HTABLE_BASE_BITS 7
+
+/* We use 0x1 as deleted marker. */
+#define HTABLE_DELETED (0x1)
+
+struct htable {
+	size_t (*rehash)(const void *elem, void *priv);
+	void *priv;
+	unsigned int bits;
+	size_t elems, deleted, max, max_with_deleted;
+	/* These are the bits which are the same in all pointers. */
+	uintptr_t common_mask, common_bits;
+	uintptr_t perfect_bit;
+	uintptr_t *table;
+};
+
+/* We clear out the bits which are always the same, and put metadata there. */
+static inline uintptr_t get_extra_ptr_bits(const struct htable *ht,
+					   uintptr_t e)
+{
+	return e & ht->common_mask;
+}
+
+static inline void *get_raw_ptr(const struct htable *ht, uintptr_t e)
+{
+	return (void *)((e & ~ht->common_mask) | ht->common_bits);
+}
+
+static inline uintptr_t make_hval(const struct htable *ht,
+				  const void *p, uintptr_t bits)
+{
+	return ((uintptr_t)p & ~ht->common_mask) | bits;
+}
+
+static inline bool entry_is_valid(uintptr_t e)
+{
+	return e > HTABLE_DELETED;
+}
+
+static inline uintptr_t get_hash_ptr_bits(const struct htable *ht,
+					  size_t hash)
+{
+	/* Shuffling the extra bits (as specified in mask) down the
+	 * end is quite expensive.  But the lower bits are redundant, so
+	 * we fold the value first. */
+	return (hash ^ (hash >> ht->bits))
+		& ht->common_mask & ~ht->perfect_bit;
+}
+
+struct htable *htable_new(size_t (*rehash)(const void *elem, void *priv),
+			  void *priv)
+{
+	struct htable *ht = malloc(sizeof(struct htable));
+	if (ht) {
+		ht->bits = HTABLE_BASE_BITS;
+		ht->rehash = rehash;
+		ht->priv = priv;
+		ht->elems = 0;
+		ht->deleted = 0;
+		ht->max = ((size_t)1 << ht->bits) * 3 / 4;
+		ht->max_with_deleted = ((size_t)1 << ht->bits) * 9 / 10;
+		/* This guarantees we enter update_common first add. */
+		ht->common_mask = -1;
+		ht->common_bits = 0;
+		ht->perfect_bit = 0;
+		ht->table = calloc(1 << ht->bits, sizeof(uintptr_t));
+		if (!ht->table) {
+			free(ht);
+			ht = NULL;
+		}
+	}
+	return ht;
+}
+
+void htable_free(const struct htable *ht)
+{
+	free((void *)ht->table);
+	free((void *)ht);
+}
+
+static size_t hash_bucket(const struct htable *ht, size_t h)
+{
+	return h & ((1 << ht->bits)-1);
+}
+
+static void *htable_val(const struct htable *ht,
+			struct htable_iter *i, size_t hash, uintptr_t perfect)
+{
+	uintptr_t h2 = get_hash_ptr_bits(ht, hash) | perfect;
+
+	while (ht->table[i->off]) {
+		if (ht->table[i->off] != HTABLE_DELETED) {
+			if (get_extra_ptr_bits(ht, ht->table[i->off]) == h2)
+				return get_raw_ptr(ht, ht->table[i->off]);
+		}
+		i->off = (i->off + 1) & ((1 << ht->bits)-1);
+		h2 &= ~perfect;
+	}
+	return NULL;
+}
+
+void *htable_firstval(const struct htable *ht,
+		      struct htable_iter *i, size_t hash)
+{
+	i->off = hash_bucket(ht, hash);
+	return htable_val(ht, i, hash, ht->perfect_bit);
+}
+
+void *htable_nextval(const struct htable *ht,
+		     struct htable_iter *i, size_t hash)
+{
+	i->off = (i->off + 1) & ((1 << ht->bits)-1);
+	return htable_val(ht, i, hash, 0);
+}
+
+void *htable_first(const struct htable *ht, struct htable_iter *i)
+{
+	for (i->off = 0; i->off < (size_t)1 << ht->bits; i->off++) {
+		if (entry_is_valid(ht->table[i->off]))
+			return get_raw_ptr(ht, ht->table[i->off]);
+	}
+	return NULL;
+}
+
+void *htable_next(const struct htable *ht, struct htable_iter *i)
+{
+	for (i->off++; i->off < (size_t)1 << ht->bits; i->off++) {
+		if (entry_is_valid(ht->table[i->off]))
+			return get_raw_ptr(ht, ht->table[i->off]);
+	}
+	return NULL;
+}
+
+/* This does not expand the hash table, that's up to caller. */
+static void ht_add(struct htable *ht, const void *new, size_t h)
+{
+	size_t i;
+	uintptr_t perfect = ht->perfect_bit;
+
+	i = hash_bucket(ht, h);
+
+	while (entry_is_valid(ht->table[i])) {
+		perfect = 0;
+		i = (i + 1) & ((1 << ht->bits)-1);
+	}
+	ht->table[i] = make_hval(ht, new, get_hash_ptr_bits(ht, h)|perfect);
+}
+
+static COLD bool double_table(struct htable *ht)
+{
+	unsigned int i;
+	size_t oldnum = (size_t)1 << ht->bits;
+	uintptr_t *oldtable, e;
+
+	oldtable = ht->table;
+	ht->table = calloc(1 << (ht->bits+1), sizeof(size_t));
+	if (!ht->table) {
+		ht->table = oldtable;
+		return false;
+	}
+	ht->bits++;
+	ht->max *= 2;
+	ht->max_with_deleted *= 2;
+
+	/* If we lost our "perfect bit", get it back now. */
+	if (!ht->perfect_bit && ht->common_mask) {
+		for (i = 0; i < sizeof(ht->common_mask) * CHAR_BIT; i++) {
+			if (ht->common_mask & ((size_t)1 << i)) {
+				ht->perfect_bit = (size_t)1 << i;
+				break;
+			}
+		}
+	}
+
+	for (i = 0; i < oldnum; i++) {
+		if (entry_is_valid(e = oldtable[i])) {
+			void *p = get_raw_ptr(ht, e);
+			ht_add(ht, p, ht->rehash(p, ht->priv));
+		}
+	}
+	ht->deleted = 0;
+	free(oldtable);
+	return true;
+}
+
+static COLD void rehash_table(struct htable *ht)
+{
+	size_t start, i;
+	uintptr_t e;
+
+	/* Beware wrap cases: we need to start from first empty bucket. */
+	for (start = 0; ht->table[start]; start++);
+
+	for (i = 0; i < (size_t)1 << ht->bits; i++) {
+		size_t h = (i + start) & ((1 << ht->bits)-1);
+		e = ht->table[h];
+		if (!e)
+			continue;
+		if (e == HTABLE_DELETED)
+			ht->table[h] = 0;
+		else if (!(e & ht->perfect_bit)) {
+			void *p = get_raw_ptr(ht, e);
+			ht->table[h] = 0;
+			ht_add(ht, p, ht->rehash(p, ht->priv));
+		}
+	}
+	ht->deleted = 0;
+}
+
+/* We stole some bits, now we need to put them back... */
+static COLD void update_common(struct htable *ht, const void *p)
+{
+	unsigned int i;
+	uintptr_t maskdiff, bitsdiff;
+
+	if (ht->elems == 0) {
+		ht->common_mask = -1;
+		ht->common_bits = (uintptr_t)p;
+		ht->perfect_bit = 1;
+		return;
+	}
+
+	/* Find bits which are unequal to old common set. */
+	maskdiff = ht->common_bits ^ ((uintptr_t)p & ht->common_mask);
+
+	/* These are the bits which go there in existing entries. */
+	bitsdiff = ht->common_bits & maskdiff;
+
+	for (i = 0; i < (size_t)1 << ht->bits; i++) {
+		if (!entry_is_valid(ht->table[i]))
+			continue;
+		/* Clear the bits no longer in the mask, set them as
+		 * expected. */
+		ht->table[i] &= ~maskdiff;
+		ht->table[i] |= bitsdiff;
+	}
+
+	/* Take away those bits from our mask, bits and perfect bit. */
+	ht->common_mask &= ~maskdiff;
+	ht->common_bits &= ~maskdiff;
+	ht->perfect_bit &= ~maskdiff;
+}
+
+bool htable_add(struct htable *ht, size_t hash, const void *p)
+{
+	if (ht->elems+1 > ht->max && !double_table(ht))
+		return false;
+	if (ht->elems+1 + ht->deleted > ht->max_with_deleted)
+		rehash_table(ht);
+	assert(p);
+	if (((uintptr_t)p & ht->common_mask) != ht->common_bits)
+		update_common(ht, p);
+
+	ht_add(ht, p, hash);
+	ht->elems++;
+	return true;
+}
+
+bool htable_del(struct htable *ht, size_t h, const void *p)
+{
+	struct htable_iter i;
+	void *c;
+
+	for (c = htable_firstval(ht,&i,h); c; c = htable_nextval(ht,&i,h)) {
+		if (c == p) {
+			htable_delval(ht, &i);
+			return true;
+		}
+	}
+	return false;
+}
+
+void htable_delval(struct htable *ht, struct htable_iter *i)
+{
+	assert(i->off < (size_t)1 << ht->bits);
+	assert(entry_is_valid(ht->table[i->off]));
+
+	ht->elems--;
+	ht->table[i->off] = HTABLE_DELETED;
+	ht->deleted++;
+}
diff --git a/lib/ccan/htable/htable.h b/lib/ccan/htable/htable.h
new file mode 100644
index 0000000000..b68442972c
--- /dev/null
+++ b/lib/ccan/htable/htable.h
@@ -0,0 +1,138 @@
+#ifndef CCAN_HTABLE_H
+#define CCAN_HTABLE_H
+#include "config.h"
+#include <stdbool.h>
+#include <stdlib.h>
+
+struct htable;
+
+/**
+ * htable_new - allocate a hash tree.
+ * @rehash: hash function to use for rehashing.
+ * @priv: private argument to @rehash function.
+ */
+struct htable *htable_new(size_t (*hash)(const void *elem, void *priv),
+			  void *priv);
+
+/**
+ * htable_free - dellocate a hash tree.
+ *
+ * This doesn't do anything to any pointers left in it.
+ */
+void htable_free(const struct htable *);
+
+/**
+ * htable_rehash - use a hashtree's rehash function
+ * @elem: the argument to rehash()
+ *
+ */
+size_t htable_rehash(const void *elem);
+
+/**
+ * htable_add - add a pointer into a hash tree.
+ * @ht: the htable
+ * @hash: the hash value of the object
+ * @p: the non-NULL pointer
+ *
+ * Also note that this can only fail due to allocation failure.  Otherwise, it
+ * returns true.
+ */
+bool htable_add(struct htable *ht, size_t hash, const void *p);
+
+/**
+ * htable_del - remove a pointer from a hash tree
+ * @ht: the htable
+ * @hash: the hash value of the object
+ * @p: the pointer
+ *
+ * Returns true if the pointer was found (and deleted).
+ */
+bool htable_del(struct htable *ht, size_t hash, const void *p);
+
+/**
+ * struct htable_iter - iterator or htable_first or htable_firstval etc.
+ *
+ * This refers to a location inside the hashtable.
+ */
+struct htable_iter {
+	size_t off;
+};
+
+/**
+ * htable_firstval - find a candidate for a given hash value
+ * @htable: the hashtable
+ * @i: the struct htable_iter to initialize
+ * @hash: the hash value
+ *
+ * You'll need to check the value is what you want; returns NULL if none.
+ * See Also:
+ *	htable_delval()
+ */
+void *htable_firstval(const struct htable *htable,
+		      struct htable_iter *i, size_t hash);
+
+/**
+ * htable_nextval - find another candidate for a given hash value
+ * @htable: the hashtable
+ * @i: the struct htable_iter to initialize
+ * @hash: the hash value
+ *
+ * You'll need to check the value is what you want; returns NULL if no more.
+ */
+void *htable_nextval(const struct htable *htable,
+		     struct htable_iter *i, size_t hash);
+
+/**
+ * htable_get - find an entry in the hash table
+ * @ht: the hashtable
+ * @h: the hash value of the entry
+ * @cmp: the comparison function
+ * @ptr: the pointer to hand to the comparison function.
+ *
+ * Convenient inline wrapper for htable_firstval/htable_nextval loop.
+ */
+static inline void *htable_get(const struct htable *ht,
+			       size_t h,
+			       bool (*cmp)(const void *candidate, void *ptr),
+			       const void *ptr)
+{
+	struct htable_iter i;
+	void *c;
+
+	for (c = htable_firstval(ht,&i,h); c; c = htable_nextval(ht,&i,h)) {
+		if (cmp(c, (void *)ptr))
+			return c;
+	}
+	return NULL;
+}
+
+/**
+ * htable_first - find an entry in the hash table
+ * @ht: the hashtable
+ * @i: the struct htable_iter to initialize
+ *
+ * Get an entry in the hashtable; NULL if empty.
+ */
+void *htable_first(const struct htable *htable, struct htable_iter *i);
+
+/**
+ * htable_next - find another entry in the hash table
+ * @ht: the hashtable
+ * @i: the struct htable_iter to use
+ *
+ * Get another entry in the hashtable; NULL if all done.
+ * This is usually used after htable_first or prior non-NULL htable_next.
+ */
+void *htable_next(const struct htable *htable, struct htable_iter *i);
+
+/**
+ * htable_delval - remove an iterated pointer from a hash tree
+ * @ht: the htable
+ * @i: the htable_iter
+ *
+ * Usually used to delete a hash entry after it has been found with
+ * htable_firstval etc.
+ */
+void htable_delval(struct htable *ht, struct htable_iter *i);
+
+#endif /* CCAN_HTABLE_H */
diff --git a/lib/ccan/htable/htable_type.h b/lib/ccan/htable/htable_type.h
new file mode 100644
index 0000000000..0d9e3fbb2d
--- /dev/null
+++ b/lib/ccan/htable/htable_type.h
@@ -0,0 +1,97 @@
+#ifndef CCAN_HTABLE_TYPE_H
+#define CCAN_HTABLE_TYPE_H
+#include <ccan/htable/htable.h>
+#include "config.h"
+
+/**
+ * HTABLE_DEFINE_TYPE - create a set of htable ops for a type
+ * @type: a type whose pointers will be values in the hash.
+ * @keyof: a function/macro to extract a key from a @type element.
+ * @hashfn: a hash function for a @key
+ * @cmpfn: a comparison function for two keyof()s.
+ * @name: a name for all the functions to define (of form htable_<name>_*)
+ *
+ * NULL values may not be placed into the hash table.
+ *
+ * The following wrapper functions are defined; each one is a
+ * simplified version of the htable.h equivalent:
+ *
+ *	// Creating and freeing.
+ *	struct htable_@name *htable_@name_new(void);
+ *	void htable_@name_free(const struct htable_@name *ht);
+ *
+ *	// Add, delete and find.
+ *	bool htable_@name_add(struct htable_@name *ht, const type *e);
+ *	bool htable_@name_del(struct htable_@name *ht, const type *e);
+ *	bool htable_@name_delkey(struct htable_@name *ht, const ktype *k);
+ *	type *htable_@name_get(const struct htable_@name *ht, const ktype *k);
+ *
+ *	// Iteration.
+ *	struct htable_@name_iter;
+ *	type *htable_@name_first(const struct htable_@name *ht,
+ *				 struct htable_@name_iter *i);
+ *	type *htable_@name_next(const struct htable_@name *ht,
+ *				struct htable_@name_iter *i);
+ */
+#define HTABLE_DEFINE_TYPE(type, keyof, hashfn, cmpfn, name)		\
+struct htable_##name;							\
+struct htable_##name##_iter { struct htable_iter i; };			\
+static inline size_t htable_##name##_hash(const void *elem, void *priv)	\
+{									\
+	return hashfn(keyof((const type *)elem));			\
+}									\
+static inline struct htable_##name *htable_##name##_new(void)		\
+{									\
+	return (struct htable_##name *)htable_new(htable_##name##_hash,	\
+						  NULL);		\
+}									\
+static inline void htable_##name##_free(const struct htable_##name *ht)	\
+{									\
+	htable_free((const struct htable *)ht);				\
+}									\
+static inline bool htable_##name##_add(struct htable_##name *ht,	\
+				       const type *elem)		\
+{									\
+	return htable_add((struct htable *)ht, hashfn(keyof(elem)), elem); \
+}									\
+static inline bool htable_##name##_del(const struct htable_##name *ht,	\
+				       const type *elem)		\
+{									\
+	return htable_del((struct htable *)ht, hashfn(keyof(elem)), elem); \
+}									\
+static inline type *htable_##name##_get(const struct htable_##name *ht,	\
+					const HTABLE_KTYPE(keyof) k)	\
+{									\
+	/* Typecheck for cmpfn */					\
+	(void)sizeof(cmpfn((const type *)NULL,				\
+			   keyof((const type *)NULL)));			\
+	return (type *)htable_get((const struct htable *)ht,		\
+				  hashfn(k),				\
+				  (bool (*)(const void *, void *))(cmpfn), \
+				  k);					\
+}									\
+static inline bool htable_##name##_delkey(struct htable_##name *ht,	\
+					  const HTABLE_KTYPE(keyof) k) \
+{									\
+	type *elem = htable_##name##_get(ht, k);			\
+	if (elem)							\
+		return htable_##name##_del(ht, elem);			\
+	return false;							\
+}									\
+static inline type *htable_##name##_first(const struct htable_##name *ht, \
+					  struct htable_##name##_iter *iter) \
+{									\
+	return htable_first((const struct htable *)ht, &iter->i);	\
+}									\
+static inline type *htable_##name##_next(const struct htable_##name *ht, \
+					 struct htable_##name##_iter *iter) \
+{									\
+	return htable_next((const struct htable *)ht, &iter->i);	\
+}
+
+#if HAVE_TYPEOF
+#define HTABLE_KTYPE(keyof) typeof(keyof(NULL))
+#else
+#define HTABLE_KTYPE(keyof) void *
+#endif
+#endif /* CCAN_HTABLE_TYPE_H */
diff --git a/lib/ccan/htable/test/run-type.c b/lib/ccan/htable/test/run-type.c
new file mode 100644
index 0000000000..02dac29e10
--- /dev/null
+++ b/lib/ccan/htable/test/run-type.c
@@ -0,0 +1,176 @@
+#include <ccan/htable/htable_type.h>
+#include <ccan/htable/htable.c>
+#include <ccan/tap/tap.h>
+#include <stdbool.h>
+#include <string.h>
+
+#define NUM_VALS (1 << HTABLE_BASE_BITS)
+
+struct obj {
+	/* Makes sure we don't try to treat and obj as a key or vice versa */
+	unsigned char unused;
+	unsigned int key;
+};
+
+static const unsigned int *objkey(const struct obj *obj)
+{
+	return &obj->key;
+}
+
+/* We use the number divided by two as the hash (for lots of
+   collisions), plus set all the higher bits so we can detect if they
+   don't get masked out. */
+static size_t objhash(const unsigned int *key)
+{
+	size_t h = *key / 2;
+	h |= -1UL << HTABLE_BASE_BITS;
+	return h;
+}
+
+static bool cmp(const struct obj *obj, const unsigned int *key)
+{
+	return obj->key == *key;
+}
+
+HTABLE_DEFINE_TYPE(struct obj, objkey, objhash, cmp, obj);
+
+static void add_vals(struct htable_obj *ht,
+		     struct obj val[], unsigned int num)
+{
+	unsigned int i;
+
+	for (i = 0; i < num; i++) {
+		if (htable_obj_get(ht, &i)) {
+			fail("%u already in hash", i);
+			return;
+		}
+		htable_obj_add(ht, &val[i]);
+		if (htable_obj_get(ht, &i) != &val[i]) {
+			fail("%u not added to hash", i);
+			return;
+		}
+	}
+	pass("Added %u numbers to hash", i);
+}
+
+static void find_vals(const struct htable_obj *ht,
+		      const struct obj val[], unsigned int num)
+{
+	unsigned int i;
+
+	for (i = 0; i < num; i++) {
+		if (htable_obj_get(ht, &i) != &val[i]) {
+			fail("%u not found in hash", i);
+			return;
+		}
+	}
+	pass("Found %u numbers in hash", i);
+}
+
+static void del_vals(struct htable_obj *ht,
+		     const struct obj val[], unsigned int num)
+{
+	unsigned int i;
+
+	for (i = 0; i < num; i++) {
+		if (!htable_obj_delkey(ht, &val[i].key)) {
+			fail("%u not deleted from hash", i);
+			return;
+		}
+	}
+	pass("Deleted %u numbers in hash", i);
+}
+
+static void del_vals_bykey(struct htable_obj *ht,
+			   const struct obj val[], unsigned int num)
+{
+	unsigned int i;
+
+	for (i = 0; i < num; i++) {
+		if (!htable_obj_delkey(ht, &i)) {
+			fail("%u not deleted by key from hash", i);
+			return;
+		}
+	}
+	pass("Deleted %u numbers by key from hash", i);
+}
+
+static bool check_mask(struct htable *ht, const struct obj val[], unsigned num)
+{
+	uint64_t i;
+
+	for (i = 0; i < num; i++) {
+		if (((uintptr_t)&val[i] & ht->common_mask) != ht->common_bits)
+			return false;
+	}
+	return true;
+}
+
+int main(int argc, char *argv[])
+{
+	unsigned int i;
+	struct htable_obj *ht;
+	struct obj val[NUM_VALS];
+	unsigned int dne;
+	void *p;
+	struct htable_obj_iter iter;
+
+	plan_tests(20);
+	for (i = 0; i < NUM_VALS; i++)
+		val[i].key = i;
+	dne = i;
+
+	ht = htable_obj_new();
+	ok1(((struct htable *)ht)->max < (1 << ((struct htable *)ht)->bits));
+	ok1(((struct htable *)ht)->bits == HTABLE_BASE_BITS);
+
+	/* We cannot find an entry which doesn't exist. */
+	ok1(!htable_obj_get(ht, &dne));
+
+	/* Fill it, it should increase in size (once). */
+	add_vals(ht, val, NUM_VALS);
+	ok1(((struct htable *)ht)->bits == HTABLE_BASE_BITS + 1);
+	ok1(((struct htable *)ht)->max < (1 << ((struct htable *)ht)->bits));
+
+	/* Mask should be set. */
+	ok1(((struct htable *)ht)->common_mask != 0);
+	ok1(((struct htable *)ht)->common_mask != -1);
+	ok1(check_mask((struct htable *)ht, val, NUM_VALS));
+
+	/* Find all. */
+	find_vals(ht, val, NUM_VALS);
+	ok1(!htable_obj_get(ht, &dne));
+
+	/* Walk once, should get them all. */
+	i = 0;
+	for (p = htable_obj_first(ht,&iter); p; p = htable_obj_next(ht, &iter))
+		i++;
+	ok1(i == NUM_VALS);
+
+	/* Delete all. */
+	del_vals(ht, val, NUM_VALS);
+	ok1(!htable_obj_get(ht, &val[0].key));
+
+	/* Worst case, a "pointer" which doesn't have any matching bits. */
+	htable_add((struct htable *)ht, 0,
+		   (void *)~(uintptr_t)&val[NUM_VALS-1]);
+	htable_obj_add(ht, &val[NUM_VALS-1]);
+	ok1(((struct htable *)ht)->common_mask == 0);
+	ok1(((struct htable *)ht)->common_bits == 0);
+	/* Delete the bogus one before we trip over it. */
+	htable_del((struct htable *)ht, 0,
+		   (void *)~(uintptr_t)&val[NUM_VALS-1]);
+
+	/* Add the rest. */
+	add_vals(ht, val, NUM_VALS-1);
+
+	/* Check we can find them all. */
+	find_vals(ht, val, NUM_VALS);
+	ok1(!htable_obj_get(ht, &dne));
+
+	/* Delete them all by key. */
+	del_vals_bykey(ht, val, NUM_VALS);
+	htable_obj_free(ht);
+
+	return exit_status();
+}
diff --git a/lib/ccan/htable/test/run.c b/lib/ccan/htable/test/run.c
new file mode 100644
index 0000000000..ece46a0fd7
--- /dev/null
+++ b/lib/ccan/htable/test/run.c
@@ -0,0 +1,176 @@
+#include <ccan/htable/htable.h>
+#include <ccan/htable/htable.c>
+#include <ccan/tap/tap.h>
+#include <stdbool.h>
+#include <string.h>
+
+#define NUM_VALS (1 << HTABLE_BASE_BITS)
+
+/* We use the number divided by two as the hash (for lots of
+   collisions), plus set all the higher bits so we can detect if they
+   don't get masked out. */
+static size_t hash(const void *elem, void *unused)
+{
+	size_t h = *(uint64_t *)elem / 2;
+	h |= -1UL << HTABLE_BASE_BITS;
+	return h;
+}
+
+static bool objcmp(const void *htelem, void *cmpdata)
+{
+	return *(uint64_t *)htelem == *(uint64_t *)cmpdata;
+}
+
+static void add_vals(struct htable *ht,
+		     const uint64_t val[], unsigned int num)
+{
+	uint64_t i;
+
+	for (i = 0; i < num; i++) {
+		if (htable_get(ht, hash(&i, NULL), objcmp, &i)) {
+			fail("%llu already in hash", (long long)i);
+			return;
+		}
+		htable_add(ht, hash(&val[i], NULL), &val[i]);
+		if (htable_get(ht, hash(&i, NULL), objcmp, &i) != &val[i]) {
+			fail("%llu not added to hash", (long long)i);
+			return;
+		}
+	}
+	pass("Added %llu numbers to hash", (long long)i);
+}
+
+#if 0
+static void refill_vals(struct htable *ht,
+			const uint64_t val[], unsigned int num)
+{
+	uint64_t i;
+
+	for (i = 0; i < num; i++) {
+		if (htable_get(ht, hash(&i, NULL), objcmp, &i))
+			continue;
+		htable_add(ht, hash(&val[i], NULL), &val[i]);
+	}
+}
+#endif
+
+static void find_vals(struct htable *ht,
+		      const uint64_t val[], unsigned int num)
+{
+	uint64_t i;
+
+	for (i = 0; i < num; i++) {
+		if (htable_get(ht, hash(&i, NULL), objcmp, &i) != &val[i]) {
+			fail("%llu not found in hash", (long long)i);
+			return;
+		}
+	}
+	pass("Found %llu numbers in hash", (long long)i);
+}
+
+static void del_vals(struct htable *ht,
+		     const uint64_t val[], unsigned int num)
+{
+	uint64_t i;
+
+	for (i = 0; i < num; i++) {
+		if (!htable_del(ht, hash(&val[i], NULL), &val[i])) {
+			fail("%llu not deleted from hash", (long long)i);
+			return;
+		}
+	}
+	pass("Deleted %llu numbers in hash", (long long)i);
+}
+
+static bool check_mask(struct htable *ht, uint64_t val[], unsigned num)
+{
+	uint64_t i;
+
+	for (i = 0; i < num; i++) {
+		if (((uintptr_t)&val[i] & ht->common_mask) != ht->common_bits)
+			return false;
+	}
+	return true;
+}
+
+int main(int argc, char *argv[])
+{
+	unsigned int i;
+	uintptr_t perfect_bit;
+	struct htable *ht;
+	uint64_t val[NUM_VALS];
+	uint64_t dne;
+	void *p;
+	struct htable_iter iter;
+
+	plan_tests(23);
+	for (i = 0; i < NUM_VALS; i++)
+		val[i] = i;
+	dne = i;
+
+	ht = htable_new(hash, NULL);
+	ok1(ht->max < (1 << ht->bits));
+	ok1(ht->bits == HTABLE_BASE_BITS);
+
+	/* We cannot find an entry which doesn't exist. */
+	ok1(!htable_get(ht, hash(&dne, NULL), objcmp, &dne));
+
+	/* Fill it, it should increase in size (once). */
+	add_vals(ht, val, NUM_VALS);
+	ok1(ht->bits == HTABLE_BASE_BITS + 1);
+	ok1(ht->max < (1 << ht->bits));
+
+	/* Mask should be set. */
+	ok1(ht->common_mask != 0);
+	ok1(ht->common_mask != -1);
+	ok1(check_mask(ht, val, NUM_VALS));
+
+	/* Find all. */
+	find_vals(ht, val, NUM_VALS);
+	ok1(!htable_get(ht, hash(&dne, NULL), objcmp, &dne));
+
+	/* Walk once, should get them all. */
+	i = 0;
+	for (p = htable_first(ht,&iter); p; p = htable_next(ht, &iter))
+		i++;
+	ok1(i == NUM_VALS);
+
+	/* Delete all. */
+	del_vals(ht, val, NUM_VALS);
+	ok1(!htable_get(ht, hash(&val[0], NULL), objcmp, &val[0]));
+
+	/* Worst case, a "pointer" which doesn't have any matching bits. */
+	htable_add(ht, 0, (void *)~(uintptr_t)&val[NUM_VALS-1]);
+	htable_add(ht, hash(&val[NUM_VALS-1], NULL), &val[NUM_VALS-1]);
+	ok1(ht->common_mask == 0);
+	ok1(ht->common_bits == 0);
+	/* Get rid of bogus pointer before we trip over it! */
+	htable_del(ht, 0, (void *)~(uintptr_t)&val[NUM_VALS-1]);
+
+	/* Add the rest. */
+	add_vals(ht, val, NUM_VALS-1);
+
+	/* Check we can find them all. */
+	find_vals(ht, val, NUM_VALS);
+	ok1(!htable_get(ht, hash(&dne, NULL), objcmp, &dne));
+
+	htable_free(ht);
+
+	/* Corner cases: wipe out the perfect bit using bogus pointer. */
+	ht = htable_new(hash, NULL);
+	htable_add(ht, 0, (void *)((uintptr_t)&val[NUM_VALS-1]));
+	ok1(ht->perfect_bit);
+	perfect_bit = ht->perfect_bit;
+	htable_add(ht, 0, (void *)((uintptr_t)&val[NUM_VALS-1]
+				   | perfect_bit));
+	ok1(ht->perfect_bit == 0);
+	htable_del(ht, 0, (void *)((uintptr_t)&val[NUM_VALS-1] | perfect_bit));
+
+	/* Enlarging should restore it... */
+	add_vals(ht, val, NUM_VALS-1);
+
+	ok1(ht->perfect_bit != 0);
+	htable_free(ht);
+
+	return exit_status();
+}
diff --git a/lib/ccan/htable/tools/Makefile b/lib/ccan/htable/tools/Makefile
new file mode 100644
index 0000000000..001e160b78
--- /dev/null
+++ b/lib/ccan/htable/tools/Makefile
@@ -0,0 +1,5 @@
+CFLAGS=-Wall -Werror -O3 -I../../..
+
+speed: speed.o ../../hash.o
+
+speed.o: speed.c ../htable.h ../htable.c
diff --git a/lib/ccan/htable/tools/speed.c b/lib/ccan/htable/tools/speed.c
new file mode 100644
index 0000000000..26231924a1
--- /dev/null
+++ b/lib/ccan/htable/tools/speed.c
@@ -0,0 +1,377 @@
+/* Simple speed tests for hashtables. */
+#include <ccan/htable/htable_type.h>
+#include <ccan/htable/htable.c>
+#include <ccan/hash/hash.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <time.h>
+#include <unistd.h>
+#include <sys/time.h>
+
+static size_t hashcount;
+struct object {
+	/* The key. */
+	unsigned int key;
+
+	/* Some contents. Doubles as consistency check. */
+	struct object *self;
+};
+
+static const unsigned int *objkey(const struct object *obj)
+{
+	return &obj->key;
+}
+
+static size_t hash_obj(const unsigned int *key)
+{
+	hashcount++;
+	return hashl(key, 1, 0);
+}
+
+static bool cmp(const unsigned int *key1, const unsigned int *key2)
+{
+	return *key1 == *key2;
+}
+
+HTABLE_DEFINE_TYPE(struct object, objkey, hash_obj, cmp, obj);
+
+static unsigned int popcount(unsigned long val)
+{
+#if HAVE_BUILTIN_POPCOUNTL
+	return __builtin_popcountl(val);
+#else
+	if (sizeof(long) == sizeof(u64)) {
+		u64 v = val;
+		v = (v & 0x5555555555555555ULL)
+			+ ((v >> 1) & 0x5555555555555555ULL);
+		v = (v & 0x3333333333333333ULL)
+			+ ((v >> 1) & 0x3333333333333333ULL);
+		v = (v & 0x0F0F0F0F0F0F0F0FULL)
+			+ ((v >> 1) & 0x0F0F0F0F0F0F0F0FULL);
+		v = (v & 0x00FF00FF00FF00FFULL)
+			+ ((v >> 1) & 0x00FF00FF00FF00FFULL);
+		v = (v & 0x0000FFFF0000FFFFULL)
+			+ ((v >> 1) & 0x0000FFFF0000FFFFULL);
+		v = (v & 0x00000000FFFFFFFFULL)
+			+ ((v >> 1) & 0x00000000FFFFFFFFULL);
+		return v;
+	}
+	val = (val & 0x55555555ULL) + ((val >> 1) & 0x55555555ULL);
+	val = (val & 0x33333333ULL) + ((val >> 1) & 0x33333333ULL);
+	val = (val & 0x0F0F0F0FULL) + ((val >> 1) & 0x0F0F0F0FULL);
+	val = (val & 0x00FF00FFULL) + ((val >> 1) & 0x00FF00FFULL);
+	val = (val & 0x0000FFFFULL) + ((val >> 1) & 0x0000FFFFULL);
+	return val;
+#endif
+}
+
+static size_t perfect(const struct htable *ht)
+{
+	size_t i, placed_perfect = 0;
+
+	for (i = 0; i < ((size_t)1 << ht->bits); i++) {
+		if (!entry_is_valid(ht->table[i]))
+			continue;
+		if (hash_bucket(ht, ht->rehash(get_raw_ptr(ht, ht->table[i]),
+					       ht->priv)) == i) {
+			assert((ht->table[i] & ht->perfect_bit)
+			       == ht->perfect_bit);
+			placed_perfect++;
+		}
+	}
+	return placed_perfect;
+}
+
+static size_t count_deleted(const struct htable *ht)
+{
+	size_t i, delete_markers = 0;
+
+	for (i = 0; i < ((size_t)1 << ht->bits); i++) {
+		if (ht->table[i] == HTABLE_DELETED)
+			delete_markers++;
+	}
+	return delete_markers;
+}
+
+/* Nanoseconds per operation */
+static size_t normalize(const struct timeval *start,
+			const struct timeval *stop,
+			unsigned int num)
+{
+	struct timeval diff;
+
+	timersub(stop, start, &diff);
+
+	/* Floating point is more accurate here. */
+	return (double)(diff.tv_sec * 1000000 + diff.tv_usec)
+		/ num * 1000;
+}
+
+static size_t worst_run(struct htable *ht, size_t *deleted)
+{
+	size_t longest = 0, len = 0, this_del = 0, i;
+
+	*deleted = 0;
+	/* This doesn't take into account end-wrap, but gives an idea. */
+	for (i = 0; i < ((size_t)1 << ht->bits); i++) {
+		if (ht->table[i]) {
+			len++;
+			if (ht->table[i] == HTABLE_DELETED)
+				this_del++;
+		} else {
+			if (len > longest) {
+				longest = len;
+				*deleted = this_del;
+			}
+			len = 0;
+			this_del = 0;
+		}
+	}
+	return longest;
+}
+
+int main(int argc, char *argv[])
+{
+	struct object *objs;
+	size_t i, j, num, deleted;
+	struct timeval start, stop;
+	struct htable_obj *ht;
+	struct htable *htr;
+	bool make_dumb = false;
+
+	if (argv[1] && strcmp(argv[1], "--dumb") == 0) {
+		argv++;
+		make_dumb = true;
+	}
+	num = argv[1] ? atoi(argv[1]) : 1000000;
+	objs = calloc(num, sizeof(objs[0]));
+
+	for (i = 0; i < num; i++) {
+		objs[i].key = i;
+		objs[i].self = &objs[i];
+	}
+
+	ht = htable_obj_new();
+	htr = (void *)ht;
+
+	printf("Initial insert: ");
+	fflush(stdout);
+	gettimeofday(&start, NULL);
+	for (i = 0; i < num; i++)
+		htable_obj_add(ht, objs[i].self);
+	gettimeofday(&stop, NULL);
+	printf(" %zu ns\n", normalize(&start, &stop, num));
+	printf("Details: hash size %u, mask bits %u, perfect %.0f%%\n",
+	       1U << htr->bits, popcount(htr->common_mask),
+	       perfect(htr) * 100.0 / htr->elems);
+
+	if (make_dumb) {
+		/* Screw with mask, to hobble us. */
+		update_common(htr, (void *)~htr->common_bits);
+		printf("Details: DUMB MODE: mask bits %u\n",
+		       popcount(htr->common_mask));
+	}
+
+	printf("Initial lookup (match): ");
+	fflush(stdout);
+	gettimeofday(&start, NULL);
+	for (i = 0; i < num; i++)
+		if (htable_obj_get(ht, &i)->self != objs[i].self)
+			abort();
+	gettimeofday(&stop, NULL);
+	printf(" %zu ns\n", normalize(&start, &stop, num));
+
+	printf("Initial lookup (miss): ");
+	fflush(stdout);
+	gettimeofday(&start, NULL);
+	for (i = 0; i < num; i++) {
+		unsigned int n = i + num;
+		if (htable_obj_get(ht, &n))
+			abort();
+	}
+	gettimeofday(&stop, NULL);
+	printf(" %zu ns\n", normalize(&start, &stop, num));
+
+	/* Lookups in order are very cache-friendly for judy; try random */
+	printf("Initial lookup (random): ");
+	fflush(stdout);
+	gettimeofday(&start, NULL);
+	for (i = 0, j = 0; i < num; i++, j = (j + 10007) % num)
+		if (htable_obj_get(ht, &j)->self != &objs[j])
+			abort();
+	gettimeofday(&stop, NULL);
+	printf(" %zu ns\n", normalize(&start, &stop, num));
+
+	hashcount = 0;
+	printf("Initial delete all: ");
+	fflush(stdout);
+	gettimeofday(&start, NULL);
+	for (i = 0; i < num; i++)
+		if (!htable_obj_del(ht, objs[i].self))
+			abort();
+	gettimeofday(&stop, NULL);
+	printf(" %zu ns\n", normalize(&start, &stop, num));
+	printf("Details: rehashes %zu\n", hashcount);
+
+	printf("Initial re-inserting: ");
+	fflush(stdout);
+	gettimeofday(&start, NULL);
+	for (i = 0; i < num; i++)
+		htable_obj_add(ht, objs[i].self);
+	gettimeofday(&stop, NULL);
+	printf(" %zu ns\n", normalize(&start, &stop, num));
+
+	hashcount = 0;
+	printf("Deleting first half: ");
+	fflush(stdout);
+	gettimeofday(&start, NULL);
+	for (i = 0; i < num; i+=2)
+		if (!htable_obj_del(ht, objs[i].self))
+			abort();
+	gettimeofday(&stop, NULL);
+	printf(" %zu ns\n", normalize(&start, &stop, num));
+
+	printf("Details: rehashes %zu, delete markers %zu\n",
+	       hashcount, count_deleted(htr));
+
+	printf("Adding (a different) half: ");
+	fflush(stdout);
+
+	for (i = 0; i < num; i+=2)
+		objs[i].key = num+i;
+
+	gettimeofday(&start, NULL);
+	for (i = 0; i < num; i+=2)
+		htable_obj_add(ht, objs[i].self);
+	gettimeofday(&stop, NULL);
+	printf(" %zu ns\n", normalize(&start, &stop, num));
+
+	printf("Details: delete markers %zu, perfect %.0f%%\n",
+	       count_deleted(htr), perfect(htr) * 100.0 / htr->elems);
+
+	printf("Lookup after half-change (match): ");
+	fflush(stdout);
+	gettimeofday(&start, NULL);
+	for (i = 1; i < num; i+=2)
+		if (htable_obj_get(ht, &i)->self != objs[i].self)
+			abort();
+	for (i = 0; i < num; i+=2) {
+		unsigned int n = i + num;
+		if (htable_obj_get(ht, &n)->self != objs[i].self)
+			abort();
+	}
+	gettimeofday(&stop, NULL);
+	printf(" %zu ns\n", normalize(&start, &stop, num));
+
+	printf("Lookup after half-change (miss): ");
+	fflush(stdout);
+	gettimeofday(&start, NULL);
+	for (i = 0; i < num; i++) {
+		unsigned int n = i + num * 2;
+		if (htable_obj_get(ht, &n))
+			abort();
+	}
+	gettimeofday(&stop, NULL);
+	printf(" %zu ns\n", normalize(&start, &stop, num));
+
+	/* Hashtables with delete markers can fill with markers over time.
+	 * so do some changes to see how it operates in long-term. */
+	for (i = 0; i < 5; i++) {
+		if (i == 0) {
+			/* We don't measure this: jmap is different. */
+			printf("Details: initial churn\n");
+		} else {
+			printf("Churning %s time: ",
+			       i == 1 ? "second"
+			       : i == 2 ? "third"
+			       : i == 3 ? "fourth"
+			       : "fifth");
+			fflush(stdout);
+		}
+		gettimeofday(&start, NULL);
+		for (j = 0; j < num; j++) {
+			if (!htable_obj_del(ht, &objs[j]))
+				abort();
+			objs[j].key = num*i+j;
+			if (!htable_obj_add(ht, &objs[j]))
+				abort();
+		}
+		gettimeofday(&stop, NULL);
+		if (i != 0)
+			printf(" %zu ns\n", normalize(&start, &stop, num));
+	}
+
+	/* Spread out the keys more to try to make it harder. */
+	printf("Details: reinserting with spread\n");
+	for (i = 0; i < num; i++) {
+		if (!htable_obj_del(ht, objs[i].self))
+			abort();
+		objs[i].key = num * 5 + i * 9;
+		if (!htable_obj_add(ht, objs[i].self))
+			abort();
+	}
+	printf("Details: delete markers %zu, perfect %.0f%%\n",
+	       count_deleted(htr), perfect(htr) * 100.0 / htr->elems);
+	i = worst_run(htr, &deleted);
+	printf("Details: worst run %zu (%zu deleted)\n", i, deleted);
+
+	printf("Lookup after churn & spread (match): ");
+	fflush(stdout);
+	gettimeofday(&start, NULL);
+	for (i = 0; i < num; i++) {
+		unsigned int n = num * 5 + i * 9;
+		if (htable_obj_get(ht, &n)->self != objs[i].self)
+			abort();
+	}
+	gettimeofday(&stop, NULL);
+	printf(" %zu ns\n", normalize(&start, &stop, num));
+
+	printf("Lookup after churn & spread (miss): ");
+	fflush(stdout);
+	gettimeofday(&start, NULL);
+	for (i = 0; i < num; i++) {
+		unsigned int n = num * (5 + 9) + i * 9;
+		if (htable_obj_get(ht, &n))
+			abort();
+	}
+	gettimeofday(&stop, NULL);
+	printf(" %zu ns\n", normalize(&start, &stop, num));
+
+	printf("Lookup after churn & spread (random): ");
+	fflush(stdout);
+	gettimeofday(&start, NULL);
+	for (i = 0, j = 0; i < num; i++, j = (j + 10007) % num) {
+		unsigned int n = num * 5 + j * 9;
+		if (htable_obj_get(ht, &n)->self != &objs[j])
+			abort();
+	}
+	gettimeofday(&stop, NULL);
+	printf(" %zu ns\n", normalize(&start, &stop, num));
+
+	hashcount = 0;
+	printf("Deleting half after churn & spread: ");
+	fflush(stdout);
+	gettimeofday(&start, NULL);
+	for (i = 0; i < num; i+=2)
+		if (!htable_obj_del(ht, objs[i].self))
+			abort();
+	gettimeofday(&stop, NULL);
+	printf(" %zu ns\n", normalize(&start, &stop, num));
+
+	printf("Adding (a different) half after churn & spread: ");
+	fflush(stdout);
+
+	for (i = 0; i < num; i+=2)
+		objs[i].key = num*6+i*9;
+
+	gettimeofday(&start, NULL);
+	for (i = 0; i < num; i+=2)
+		htable_obj_add(ht, objs[i].self);
+	gettimeofday(&stop, NULL);
+	printf(" %zu ns\n", normalize(&start, &stop, num));
+
+	printf("Details: delete markers %zu, perfect %.0f%%\n",
+	       count_deleted(htr), perfect(htr) * 100.0 / htr->elems);
+
+	return 0;
+}
diff --git a/lib/ccan/ilog/LICENSE b/lib/ccan/ilog/LICENSE
new file mode 100644
index 0000000000..5522aa5f33
--- /dev/null
+++ b/lib/ccan/ilog/LICENSE
@@ -0,0 +1,508 @@
+
+                  GNU LESSER GENERAL PUBLIC LICENSE
+                       Version 2.1, February 1999
+
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+
+That's all there is to it!
diff --git a/lib/ccan/ilog/_info b/lib/ccan/ilog/_info
new file mode 100644
index 0000000000..56de50d610
--- /dev/null
+++ b/lib/ccan/ilog/_info
@@ -0,0 +1,47 @@
+/**
+ * ilog - Integer logarithm.
+ *
+ * ilog_32() and ilog_64() compute the minimum number of bits required to store
+ *  an unsigned 32-bit or 64-bit value without any leading zero bits.
+ * This can also be thought of as the location of the highest set bit, with
+ *  counting starting from one (so that 0 returns 0, 1 returns 1, and 2**31
+ *  returns 32).
+ * When the value is known to be non-zero ilog32_nz() and ilog64_nz() can
+ *  compile into as few as two instructions, one of which may get optimized out
+ *  later.
+ * STATIC_ILOG_32 and STATIC_ILOG_64 allow computation on compile-time
+ *  constants, so other compile-time constants can be derived from them.
+ *
+ * Example:
+ *  #include <stdio.h>
+ *  #include <limits.h>
+ *  #include <ccan/ilog/ilog.h>
+ *
+ *  int main(void){
+ *    int i;
+ *    printf("ilog32(0x%08X)=%i\n",0,ilog32(0));
+ *    for(i=1;i<=STATIC_ILOG_32(USHRT_MAX);i++){
+ *      uint32_t v;
+ *      v=(uint32_t)1U<<(i-1);
+ *      //Here we know v is non-zero, so we can use ilog32_nz().
+ *      printf("ilog32(0x%08X)=%i\n",v,ilog32_nz(v));
+ *    }
+ *    return 0;
+ *  }
+ *
+ * License: LGPL (v2 or later)
+ * Author: Timothy B. Terriberry <tterribe@xiph.org>
+ */
+#include <string.h>
+#include <stdio.h>
+#include "config.h"
+
+int main(int _argc,const char *_argv[]){
+  /*Expect exactly one argument.*/
+  if(_argc!=2)return 1;
+  if(strcmp(_argv[1],"depends")==0){
+    printf("ccan/compiler\n");
+    return 0;
+  }
+  return 1;
+}
diff --git a/lib/ccan/ilog/ilog.c b/lib/ccan/ilog/ilog.c
new file mode 100644
index 0000000000..40c5a6fd50
--- /dev/null
+++ b/lib/ccan/ilog/ilog.c
@@ -0,0 +1,139 @@
+/*(C) Timothy B. Terriberry (tterribe@xiph.org) 2001-2009 LGPL (v2 or later).*/
+#include "ilog.h"
+#include <limits.h>
+
+/*The fastest fallback strategy for platforms with fast multiplication appears
+   to be based on de Bruijn sequences~\cite{LP98}.
+  Tests confirmed this to be true even on an ARM11, where it is actually faster
+   than using the native clz instruction.
+  Define ILOG_NODEBRUIJN to use a simpler fallback on platforms where
+   multiplication or table lookups are too expensive.
+
+  @UNPUBLISHED{LP98,
+    author="Charles E. Leiserson and Harald Prokop",
+    title="Using de {Bruijn} Sequences to Index a 1 in a Computer Word",
+    month=Jun,
+    year=1998,
+    note="\url{http://supertech.csail.mit.edu/papers/debruijn.pdf}"
+  }*/
+static UNNEEDED const unsigned char DEBRUIJN_IDX32[32]={
+   0, 1,28, 2,29,14,24, 3,30,22,20,15,25,17, 4, 8,
+  31,27,13,23,21,19,16, 7,26,12,18, 6,11, 5,10, 9
+};
+
+/* We always compile these in, in case someone takes address of function. */
+#undef ilog32_nz
+#undef ilog32
+#undef ilog64_nz
+#undef ilog64
+
+int ilog32(uint32_t _v){
+/*On a Pentium M, this branchless version tested as the fastest version without
+   multiplications on 1,000,000,000 random 32-bit integers, edging out a
+   similar version with branches, and a 256-entry LUT version.*/
+# if defined(ILOG_NODEBRUIJN)
+  int ret;
+  int m;
+  ret=_v>0;
+  m=(_v>0xFFFFU)<<4;
+  _v>>=m;
+  ret|=m;
+  m=(_v>0xFFU)<<3;
+  _v>>=m;
+  ret|=m;
+  m=(_v>0xFU)<<2;
+  _v>>=m;
+  ret|=m;
+  m=(_v>3)<<1;
+  _v>>=m;
+  ret|=m;
+  ret+=_v>1;
+  return ret;
+/*This de Bruijn sequence version is faster if you have a fast multiplier.*/
+# else
+  int ret;
+  ret=_v>0;
+  _v|=_v>>1;
+  _v|=_v>>2;
+  _v|=_v>>4;
+  _v|=_v>>8;
+  _v|=_v>>16;
+  _v=(_v>>1)+1;
+  ret+=DEBRUIJN_IDX32[_v*0x77CB531U>>27&0x1F];
+  return ret;
+# endif
+}
+
+int ilog32_nz(uint32_t _v)
+{
+  return ilog32(_v);
+}
+
+int ilog64(uint64_t _v){
+# if defined(ILOG_NODEBRUIJN)
+  uint32_t v;
+  int      ret;
+  int      m;
+  ret=_v>0;
+  m=(_v>0xFFFFFFFFU)<<5;
+  v=(uint32_t)(_v>>m);
+  ret|=m;
+  m=(v>0xFFFFU)<<4;
+  v>>=m;
+  ret|=m;
+  m=(v>0xFFU)<<3;
+  v>>=m;
+  ret|=m;
+  m=(v>0xFU)<<2;
+  v>>=m;
+  ret|=m;
+  m=(v>3)<<1;
+  v>>=m;
+  ret|=m;
+  ret+=v>1;
+  return ret;
+# else
+/*If we don't have a 64-bit word, split it into two 32-bit halves.*/
+#  if LONG_MAX<9223372036854775807LL
+  uint32_t v;
+  int      ret;
+  int      m;
+  ret=_v>0;
+  m=(_v>0xFFFFFFFFU)<<5;
+  v=(uint32_t)(_v>>m);
+  ret|=m;
+  v|=v>>1;
+  v|=v>>2;
+  v|=v>>4;
+  v|=v>>8;
+  v|=v>>16;
+  v=(v>>1)+1;
+  ret+=DEBRUIJN_IDX32[v*0x77CB531U>>27&0x1F];
+  return ret;
+/*Otherwise do it in one 64-bit operation.*/
+#  else
+  static const unsigned char DEBRUIJN_IDX64[64]={
+     0, 1, 2, 7, 3,13, 8,19, 4,25,14,28, 9,34,20,40,
+     5,17,26,38,15,46,29,48,10,31,35,54,21,50,41,57,
+    63, 6,12,18,24,27,33,39,16,37,45,47,30,53,49,56,
+    62,11,23,32,36,44,52,55,61,22,43,51,60,42,59,58
+  };
+  int ret;
+  ret=_v>0;
+  _v|=_v>>1;
+  _v|=_v>>2;
+  _v|=_v>>4;
+  _v|=_v>>8;
+  _v|=_v>>16;
+  _v|=_v>>32;
+  _v=(_v>>1)+1;
+  ret+=DEBRUIJN_IDX64[_v*0x218A392CD3D5DBF>>58&0x3F];
+  return ret;
+#  endif
+# endif
+}
+
+int ilog64_nz(uint64_t _v)
+{
+  return ilog64(_v);
+}
diff --git a/lib/ccan/ilog/ilog.h b/lib/ccan/ilog/ilog.h
new file mode 100644
index 0000000000..55dd009885
--- /dev/null
+++ b/lib/ccan/ilog/ilog.h
@@ -0,0 +1,150 @@
+#if !defined(_ilog_H)
+# define _ilog_H (1)
+# include "config.h"
+# include <stdint.h>
+# include <limits.h>
+# include <ccan/compiler/compiler.h>
+
+/**
+ * ilog32 - Integer binary logarithm of a 32-bit value.
+ * @_v: A 32-bit value.
+ * Returns floor(log2(_v))+1, or 0 if _v==0.
+ * This is the number of bits that would be required to represent _v in two's
+ *  complement notation with all of the leading zeros stripped.
+ * Note that many uses will resolve to the fast macro version instead.
+ *
+ * See Also:
+ *	ilog32_nz(), ilog64()
+ *
+ * Example:
+ *	// Rounds up to next power of 2 (if not a power of 2).
+ *	static uint32_t round_up32(uint32_t i)
+ *	{
+ *		assert(i != 0);
+ *		return 1U << ilog32(i-1);
+ *	}
+ */
+int ilog32(uint32_t _v) IDEMPOTENT;
+
+/**
+ * ilog32_nz - Integer binary logarithm of a non-zero 32-bit value.
+ * @_v: A 32-bit value.
+ * Returns floor(log2(_v))+1, or undefined if _v==0.
+ * This is the number of bits that would be required to represent _v in two's
+ *  complement notation with all of the leading zeros stripped.
+ * Note that many uses will resolve to the fast macro version instead.
+ * See Also:
+ *	ilog32(), ilog64_nz()
+ * Example:
+ *	// Find Last Set (ie. highest bit set, 0 to 31).
+ *	static uint32_t fls32(uint32_t i)
+ *	{
+ *		assert(i != 0);
+ *		return ilog32_nz(i) - 1;
+ *	}
+ */
+int ilog32_nz(uint32_t _v) IDEMPOTENT;
+
+/**
+ * ilog64 - Integer binary logarithm of a 64-bit value.
+ * @_v: A 64-bit value.
+ * Returns floor(log2(_v))+1, or 0 if _v==0.
+ * This is the number of bits that would be required to represent _v in two's
+ *  complement notation with all of the leading zeros stripped.
+ * Note that many uses will resolve to the fast macro version instead.
+ * See Also:
+ *	ilog64_nz(), ilog32()
+ */
+int ilog64(uint64_t _v) IDEMPOTENT;
+
+/**
+ * ilog64_nz - Integer binary logarithm of a non-zero 64-bit value.
+ * @_v: A 64-bit value.
+ * Returns floor(log2(_v))+1, or undefined if _v==0.
+ * This is the number of bits that would be required to represent _v in two's
+ *  complement notation with all of the leading zeros stripped.
+ * Note that many uses will resolve to the fast macro version instead.
+ * See Also:
+ *	ilog64(), ilog32_nz()
+ */
+int ilog64_nz(uint64_t _v) IDEMPOTENT;
+
+/**
+ * STATIC_ILOG_32 - The integer logarithm of an (unsigned, 32-bit) constant.
+ * @_v: A non-negative 32-bit constant.
+ * Returns floor(log2(_v))+1, or 0 if _v==0.
+ * This is the number of bits that would be required to represent _v in two's
+ *  complement notation with all of the leading zeros stripped.
+ * This macro should only be used when you need a compile-time constant,
+ * otherwise ilog32 or ilog32_nz are just as fast and more flexible.
+ *
+ * Example:
+ *	#define MY_PAGE_SIZE	4096
+ *	#define MY_PAGE_BITS	(STATIC_ILOG_32(PAGE_SIZE) - 1)
+ */
+#define STATIC_ILOG_32(_v) (STATIC_ILOG5((uint32_t)(_v)))
+
+/**
+ * STATIC_ILOG_64 - The integer logarithm of an (unsigned, 64-bit) constant.
+ * @_v: A non-negative 64-bit constant.
+ * Returns floor(log2(_v))+1, or 0 if _v==0.
+ * This is the number of bits that would be required to represent _v in two's
+ *  complement notation with all of the leading zeros stripped.
+ * This macro should only be used when you need a compile-time constant,
+ * otherwise ilog64 or ilog64_nz are just as fast and more flexible.
+ */
+#define STATIC_ILOG_64(_v) (STATIC_ILOG6((uint64_t)(_v)))
+
+/* Private implementation details */
+
+/*Note the casts to (int) below: this prevents "upgrading"
+   the type of an entire expression to an (unsigned) size_t.*/
+#if INT_MAX>=2147483647 && HAVE_BUILTIN_CLZ
+#define builtin_ilog32_nz(v) \
+	(((int)sizeof(unsigned)*CHAR_BIT) - __builtin_clz(v))
+#elif LONG_MAX>=2147483647L && HAVE_BUILTIN_CLZL
+#define builtin_ilog32_nz(v) \
+	(((int)sizeof(unsigned)*CHAR_BIT) - __builtin_clzl(v))
+#endif
+
+#if INT_MAX>=9223372036854775807LL && HAVE_BUILTIN_CLZ
+#define builtin_ilog64_nz(v) \
+	(((int)sizeof(unsigned)*CHAR_BIT) - __builtin_clz(v))
+#elif LONG_MAX>=9223372036854775807LL && HAVE_BUILTIN_CLZL
+#define builtin_ilog64_nz(v) \
+	(((int)sizeof(unsigned long)*CHAR_BIT) - __builtin_clzl(v))
+#elif HAVE_BUILTIN_CLZLL
+#define builtin_ilog64_nz(v) \
+	(((int)sizeof(unsigned long long)*CHAR_BIT) - __builtin_clzll(v))
+#endif
+
+#ifdef builtin_ilog32_nz
+#define ilog32(_v) (builtin_ilog32_nz(_v)&-!!(_v))
+#define ilog32_nz(_v) builtin_ilog32_nz(_v)
+#else
+#define ilog32_nz(_v) ilog32(_v)
+#define ilog32(_v) (IS_COMPILE_CONSTANT(_v) ? STATIC_ILOG_32(_v) : ilog32(_v))
+#endif /* builtin_ilog32_nz */
+
+#ifdef builtin_ilog64_nz
+#define ilog64(_v) (builtin_ilog64_nz(_v)&-!!(_v))
+#define ilog64_nz(_v) builtin_ilog64_nz(_v)
+#else
+#define ilog64_nz(_v) ilog64(_v)
+#define ilog64(_v) (IS_COMPILE_CONSTANT(_v) ? STATIC_ILOG_64(_v) : ilog64(_v))
+#endif /* builtin_ilog64_nz */
+
+/* Macros for evaluating compile-time constant ilog. */
+# define STATIC_ILOG0(_v) (!!(_v))
+# define STATIC_ILOG1(_v) (((_v)&0x2)?2:STATIC_ILOG0(_v))
+# define STATIC_ILOG2(_v) (((_v)&0xC)?2+STATIC_ILOG1((_v)>>2):STATIC_ILOG1(_v))
+# define STATIC_ILOG3(_v) \
+ (((_v)&0xF0)?4+STATIC_ILOG2((_v)>>4):STATIC_ILOG2(_v))
+# define STATIC_ILOG4(_v) \
+ (((_v)&0xFF00)?8+STATIC_ILOG3((_v)>>8):STATIC_ILOG3(_v))
+# define STATIC_ILOG5(_v) \
+ (((_v)&0xFFFF0000)?16+STATIC_ILOG4((_v)>>16):STATIC_ILOG4(_v))
+# define STATIC_ILOG6(_v) \
+ (((_v)&0xFFFFFFFF00000000ULL)?32+STATIC_ILOG5((_v)>>32):STATIC_ILOG5(_v))
+
+#endif /* _ilog_H */
diff --git a/lib/ccan/ilog/test/run-out-of-line.c b/lib/ccan/ilog/test/run-out-of-line.c
new file mode 100644
index 0000000000..48205d380e
--- /dev/null
+++ b/lib/ccan/ilog/test/run-out-of-line.c
@@ -0,0 +1,65 @@
+#include <ccan/ilog/ilog.h>
+#include <ccan/ilog/ilog.c>
+#include <stdio.h>
+#include <ccan/tap/tap.h>
+
+/*Dead simple (but slow) versions to compare against.*/
+
+static int test_ilog32(uint32_t _v){
+  int ret;
+  for(ret=0;_v;ret++)_v>>=1;
+  return ret;
+}
+
+static int test_ilog64(uint64_t _v){
+  int ret;
+  for(ret=0;_v;ret++)_v>>=1;
+  return ret;
+}
+
+#define NTRIALS (64)
+
+int main(int _argc,const char *_argv[]){
+  int i;
+  int j;
+  int (*il32)(uint32_t) = ilog32;
+  int (*il64)(uint64_t) = ilog64;
+  int (*il32_nz)(uint32_t) = ilog32_nz;
+  int (*il64_nz)(uint64_t) = ilog64_nz;
+
+  /*This is how many tests you plan to run.*/
+  plan_tests(33 * NTRIALS * 3 + 65 * NTRIALS * 3);
+  for(i=0;i<=32;i++){
+    uint32_t v;
+    /*Test each bit in turn (and 0).*/
+    v=i?(uint32_t)1U<<(i-1):0;
+    for(j=0;j<NTRIALS;j++){
+      int l;
+      l=test_ilog32(v);
+      ok1(STATIC_ILOG_32(v)==l);
+      ok1(il32(v)==l);
+      ok1(il32_nz(v) == l || v == 0);
+      /*Also try a few more pseudo-random values with at most the same number
+         of bits.*/
+      v=(1103515245U*v+12345U)&0xFFFFFFFFU>>((33-i)>>1)>>((32-i)>>1);
+    }
+  }
+
+  for(i=0;i<=64;i++){
+    uint64_t v;
+    /*Test each bit in turn (and 0).*/
+    v=i?(uint64_t)1U<<(i-1):0;
+    for(j=0;j<NTRIALS;j++){
+      int l;
+      l=test_ilog64(v);
+      ok1(STATIC_ILOG_64(v)==l);
+      ok1(il64(v)==l);
+      ok1(il64_nz(v) == l || v == 0);
+      /*Also try a few more pseudo-random values with at most the same number
+         of bits.*/
+      v=(uint64_t)((2862933555777941757ULL*v+3037000493ULL)
+	&0xFFFFFFFFFFFFFFFFULL>>((65-i)>>1)>>((64-i)>>1));
+    }
+  }
+  return exit_status();
+}
diff --git a/lib/ccan/ilog/test/run.c b/lib/ccan/ilog/test/run.c
new file mode 100644
index 0000000000..bda59f920a
--- /dev/null
+++ b/lib/ccan/ilog/test/run.c
@@ -0,0 +1,60 @@
+#include <ccan/ilog/ilog.h>
+#include <ccan/ilog/ilog.c>
+#include <stdio.h>
+#include <ccan/tap/tap.h>
+
+/*Dead simple (but slow) versions to compare against.*/
+
+static int test_ilog32(uint32_t _v){
+  int ret;
+  for(ret=0;_v;ret++)_v>>=1;
+  return ret;
+}
+
+static int test_ilog64(uint64_t _v){
+  int ret;
+  for(ret=0;_v;ret++)_v>>=1;
+  return ret;
+}
+
+#define NTRIALS (64)
+
+int main(int _argc,const char *_argv[]){
+  int i;
+  int j;
+  /*This is how many tests you plan to run.*/
+  plan_tests(33 * NTRIALS * 3 + 65 * NTRIALS * 3);
+  for(i=0;i<=32;i++){
+    uint32_t v;
+    /*Test each bit in turn (and 0).*/
+    v=i?(uint32_t)1U<<(i-1):0;
+    for(j=0;j<NTRIALS;j++){
+      int l;
+      l=test_ilog32(v);
+      ok1(STATIC_ILOG_32(v)==l);
+      ok1(ilog32(v)==l);
+      ok1(ilog32_nz(v) == l || v == 0);
+      /*Also try a few more pseudo-random values with at most the same number
+         of bits.*/
+      v=(1103515245U*v+12345U)&0xFFFFFFFFU>>((33-i)>>1)>>((32-i)>>1);
+    }
+  }
+
+  for(i=0;i<=64;i++){
+    uint64_t v;
+    /*Test each bit in turn (and 0).*/
+    v=i?(uint64_t)1U<<(i-1):0;
+    for(j=0;j<NTRIALS;j++){
+      int l;
+      l=test_ilog64(v);
+      ok1(STATIC_ILOG_64(v)==l);
+      ok1(ilog64(v)==l);
+      ok1(ilog64_nz(v) == l || v == 0);
+      /*Also try a few more pseudo-random values with at most the same number
+         of bits.*/
+      v=(uint64_t)((2862933555777941757ULL*v+3037000493ULL)
+	&0xFFFFFFFFFFFFFFFFULL>>((65-i)>>1)>>((64-i)>>1));
+    }
+  }
+  return exit_status();
+}
diff --git a/lib/ccan/libccan.m4 b/lib/ccan/libccan.m4
new file mode 100644
index 0000000000..92676c3184
--- /dev/null
+++ b/lib/ccan/libccan.m4
@@ -0,0 +1,315 @@
+dnl find the ccan sources.
+ccandir="../lib/ccan"
+for d in $ccanpaths; do
+	if test -f "$srcdir/$d/str/str.c"; then
+		ccandir="$d"
+		AC_SUBST(ccandir)
+		break
+	fi
+done
+if test -f "$ccandir/str/str.c"; then :; else
+   AC_MSG_ERROR([cannot find ccan source in $ccandir])
+fi
+CCAN_OBJ="$ccandir/hash/hash.o $ccandir/htable/htable.o $ccandir/ilog/ilog.o $ccandir/likely/likely.o $ccandir/str/debug.o $ccandir/str/str.o $ccandir/tally/tally.o"
+
+AC_SUBST(CCAN_OBJ)
+
+# Preferred method for including ccan modules is #include <ccan/module/...>.
+CCAN_CFLAGS="-I$ccandir/.."
+AC_SUBST(CCAN_CFLAGS)
+
+# All the configuration checks.  Regrettably, the __attribute__ checks will
+# give false positives on old GCCs, since they just cause warnings.  But that's
+# fairly harmless.
+AC_CACHE_CHECK([whether we can compile with __attribute__((cold))],
+	       samba_cv_attribute_cold,
+	       [
+	         AC_COMPILE_IFELSE(
+			[
+				static void __attribute__((cold))
+				cleanup(void) { }
+			],
+			samba_cv_attribute_cold=yes)
+		])
+
+if test x"$samba_cv_attribute_cold" = xyes ; then
+   AC_DEFINE(HAVE_ATTRIBUTE_COLD, 1,
+	     [whether we can compile with __attribute__((cold))])
+fi
+
+AC_CACHE_CHECK([whether we can compile with __attribute__((const))],
+	       samba_cv_attribute_const,
+	       [
+	         AC_COMPILE_IFELSE(
+			[
+				static void __attribute__((const))
+				cleanup(void) { }
+			],
+			samba_cv_attribute_const=yes)
+		])
+
+if test x"$samba_cv_attribute_const" = xyes ; then
+   AC_DEFINE(HAVE_ATTRIBUTE_CONST, 1,
+	     [whether we can compile with __attribute__((const))])
+fi
+
+AC_CACHE_CHECK([whether we can compile with __attribute__((noreturn))],
+	       samba_cv_attribute_noreturn,
+	       [
+	         AC_COMPILE_IFELSE(
+			[
+				static void __attribute__((noreturn))
+				cleanup(void) { exit(1); }
+			],
+			samba_cv_attribute_noreturn=yes)
+		])
+
+if test x"$samba_cv_attribute_noreturn" = xyes ; then
+   AC_DEFINE(HAVE_ATTRIBUTE_NORETURN, 1,
+	     [whether we can compile with __attribute__((noreturn))])
+fi
+
+AC_CACHE_CHECK([whether we can compile with __attribute__((printf))],
+	       samba_cv_attribute_printf,
+	       [
+	         AC_COMPILE_IFELSE(
+			[
+				static void __attribute__((format(__printf__, 1, 2)))
+				cleanup(const char *fmt, ...) { }
+			],
+			samba_cv_attribute_printf=yes)
+		])
+
+if test x"$samba_cv_attribute_printf" = xyes ; then
+   AC_DEFINE(HAVE_ATTRIBUTE_PRINTF, 1,
+	     [whether we can compile with __attribute__((format(printf)))])
+fi
+
+AC_CACHE_CHECK([whether we can compile with __attribute__((unused))],
+	       samba_cv_attribute_unused,
+	       [
+	         AC_COMPILE_IFELSE(
+			[
+				static void __attribute__((unused))
+				cleanup(void) { }
+			],
+			samba_cv_attribute_unused=yes)
+		])
+
+if test x"$samba_cv_attribute_unused" = xyes ; then
+   AC_DEFINE(HAVE_ATTRIBUTE_UNUSED, 1,
+	     [whether we can compile with __attribute__((unused))])
+fi
+
+AC_CACHE_CHECK([whether we can compile with __attribute__((used))],
+	       samba_cv_attribute_used,
+	       [
+	         AC_COMPILE_IFELSE(
+			[
+				static void __attribute__((used))
+				cleanup(void) { }
+			],
+			samba_cv_attribute_used=yes)
+		])
+
+if test x"$samba_cv_attribute_used" = xyes ; then
+   AC_DEFINE(HAVE_ATTRIBUTE_USED, 1,
+	     [whether we can compile with __attribute__((used))])
+fi
+
+# FIXME: We could use endian.h or sys/endian.h here, and __BYTE_ORDER for
+# cross-compiling.
+AC_CACHE_CHECK([whether we are big endian],samba_cv_big_endian,[
+AC_TRY_RUN([int main(void) {
+union { int i; char c[sizeof(int)]; } u;
+	  u.i = 0x01020304;
+	  return u.c[0] == 0x01 && u.c[1] == 0x02 && u.c[2] == 0x03 && u.c[3] == 0x04 ? 0 : 1;
+}],
+samba_cv_big_endian=yes,
+samba_cv_big_endian=no)])
+if test x"$samba_cv_big_endian" = xyes ; then
+   AC_DEFINE(HAVE_BIG_ENDIAN, 1,
+	     [whether we are big endian])
+fi
+
+AC_CACHE_CHECK([whether we have __builtin_clz],
+	       samba_cv_builtin_clz,
+	       [
+	         AC_COMPILE_IFELSE(
+			[int main(void) {
+				return __builtin_clz(1) == (sizeof(int)*8 - 1) ? 0 : 1;
+			}],
+			samba_cv_builtin_clz=yes)
+		])
+
+if test x"$samba_cv_builtin_clz" = xyes ; then
+   AC_DEFINE(HAVE_BUILTIN_CLZ, 1,
+	     [whether we have __builtin_clz])
+fi
+
+AC_CACHE_CHECK([whether we have __builtin_clzl],
+	       samba_cv_builtin_clzl,
+	       [
+	         AC_COMPILE_IFELSE(
+			[int main(void) {
+				return __builtin_clzl(1) == (sizeof(int)*8 - 1) ? 0 : 1;
+			}],
+			samba_cv_builtin_clzl=yes)
+		])
+
+if test x"$samba_cv_builtin_clzl" = xyes ; then
+   AC_DEFINE(HAVE_BUILTIN_CLZL, 1,
+	     [whether we have __builtin_clzl])
+fi
+AC_CACHE_CHECK([whether we have __builtin_clzll],
+	       samba_cv_builtin_clzll,
+	       [
+	         AC_COMPILE_IFELSE(
+			[int main(void) {
+				return __builtin_clzll(1) == (sizeof(int)*8 - 1) ? 0 : 1;
+			}],
+			samba_cv_builtin_clzll=yes)
+		])
+
+if test x"$samba_cv_builtin_clzll" = xyes ; then
+   AC_DEFINE(HAVE_BUILTIN_CLZLL, 1,
+	     [whether we have __builtin_clzll])
+fi
+
+AC_CACHE_CHECK([whether we have __builtin_constant_p],
+	       samba_cv_builtin_constant_p,
+	       [
+	         AC_COMPILE_IFELSE(
+			[int main(void) {
+				return __builtin_constant_p(1) ? 0 : 1;
+			}],
+			samba_cv_builtin_constant_p=yes)
+		])
+
+if test x"$samba_cv_builtin_constant_p" = xyes ; then
+   AC_DEFINE(HAVE_BUILTIN_CONSTANT_P, 1,
+	     [whether we have __builtin_constant_p])
+fi
+
+AC_CACHE_CHECK([whether we have __builtin_expect],
+	       samba_cv_builtin_expect,
+	       [
+	         AC_COMPILE_IFELSE(
+			[int main(void) {
+				return __builtin_expect(main != 0) ? 0 : 1;
+			}],
+			samba_cv_builtin_expect=yes)
+		])
+
+if test x"$samba_cv_builtin_expect" = xyes ; then
+   AC_DEFINE(HAVE_BUILTIN_EXPECT, 1,
+	     [whether we have __builtin_expect])
+fi
+
+AC_CACHE_CHECK([whether we have __builtin_popcountl],
+	       samba_cv_builtin_popcountl,
+	       [
+	         AC_COMPILE_IFELSE(
+			[int main(void) {
+				return __builtin_popcountl(255L) == 8 ? 0 : 1;
+			}],
+			samba_cv_builtin_popcountl=yes)
+		])
+
+if test x"$samba_cv_builtin_popcountl" = xyes ; then
+   AC_DEFINE(HAVE_BUILTIN_POPCOUNTL, 1,
+	     [whether we have __builtin_popcountl])
+fi
+
+AC_CACHE_CHECK([whether we have __builtin_types_compatible_p],
+	       samba_cv_builtin_types_compatible_p,
+	       [
+	         AC_COMPILE_IFELSE(
+			[int main(void) {
+				return __builtin_types_compatible_p(char *, int) ? 1 : 0;
+			}],
+			samba_cv_builtin_types_compatible_p=yes)
+		])
+
+if test x"$samba_cv_builtin_types_compatible_p" = xyes ; then
+   AC_DEFINE(HAVE_BUILTIN_TYPES_COMPATIBLE_P, 1,
+	     [whether we have __builtin_types_compatible_p])
+fi
+
+AC_CACHE_CHECK([whether we have __builtin_compound_literals],
+	       samba_cv_builtin_compound_literals,
+	       [
+	         AC_COMPILE_IFELSE(
+			[int main(void) {
+				int *foo = (int[]) { 1, 2, 3, 4 };
+				return foo[0] == 1 ? 0 : 1;
+			}],
+			samba_cv_builtin_compound_literals=yes)
+		])
+
+if test x"$samba_cv_builtin_compound_literals" = xyes ; then
+   AC_DEFINE(HAVE_BUILTIN_COMPOUND_LITERALS, 1,
+	     [whether we have __builtin_compound_literals])
+fi
+
+AC_CACHE_CHECK([whether we have __builtin_have_isblank],
+	       samba_cv_builtin_have_isblank,
+	       [
+	         AC_COMPILE_IFELSE(
+			[#include <ctype.h>
+			 int main(void) { return isblank(' ') ? 0 : 1; }
+			],
+			samba_cv_builtin_have_isblank=yes)
+		])
+
+if test x"$samba_cv_builtin_have_isblank" = xyes ; then
+   AC_DEFINE(HAVE_BUILTIN_HAVE_ISBLANK, 1,
+	     [whether we have __builtin_have_isblank])
+fi
+
+# FIXME: We could use endian.h or sys/endian.h here, and __BYTE_ORDER for
+# cross-compiling.
+AC_CACHE_CHECK([whether we are little endian],samba_cv_little_endian,[
+AC_TRY_RUN([int main(void) {
+union { int i; char c[sizeof(int)]; } u;
+	  u.i = 0x01020304;
+	  return u.c[0] == 0x04 && u.c[1] == 0x03 && u.c[2] == 0x02 && u.c[3] == 0x01 ? 0 : 1;
+}],
+samba_cv_little_endian=yes,
+samba_cv_little_endian=no)])
+if test x"$samba_cv_little_endian" = xyes ; then
+   AC_DEFINE(HAVE_LITTLE_ENDIAN, 1,
+	     [whether we are little endian])
+fi
+
+AC_CACHE_CHECK([whether we have __typeof__],
+	       samba_cv_typeof,
+	       [
+	         AC_COMPILE_IFELSE(
+			[int main(void) {
+				int x = 1;
+				__typeof__(x) i;
+				i = x;
+				return i == x ? 0 : 1;
+			}],
+			samba_cv_typeof=yes)
+		])
+
+if test x"$samba_cv_typeof" = xyes ; then
+   AC_DEFINE(HAVE_TYPEOF, 1,
+	     [whether we have __typeof__])
+fi
+
+AC_CACHE_CHECK([whether we have __attribute__((warn_unused_result))],
+	       samba_cv_warn_unused_result,
+	       [
+	         AC_COMPILE_IFELSE(
+			[int __attribute__((warn_unused_result)) func(int x)
+			    { return x; }],
+			samba_cv_warn_unused_result=yes)
+		])
+
+if test x"$samba_cv_warn_unused_result" = xyes ; then
+   AC_DEFINE(HAVE_WARN_UNUSED_RESULT, 1,
+	     [whether we have __attribute__((warn_unused_result))])
+fi
diff --git a/lib/ccan/likely/LICENSE b/lib/ccan/likely/LICENSE
new file mode 100644
index 0000000000..5522aa5f33
--- /dev/null
+++ b/lib/ccan/likely/LICENSE
@@ -0,0 +1,508 @@
+
+                  GNU LESSER GENERAL PUBLIC LICENSE
+                       Version 2.1, February 1999
+
+ Copyright (C) 1991, 1999 Free Software Foundation, Inc.
+	51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+[This is the first released version of the Lesser GPL.  It also counts
+ as the successor of the GNU Library Public License, version 2, hence
+ the version number 2.1.]
+
+                            Preamble
+
+  The licenses for most software are designed to take away your
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+
+  This license, the Lesser General Public License, applies to some
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+can use it too, but we suggest you first think carefully about whether
+this license or the ordinary General Public License is the better
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+original licensor to copy, distribute, link with or modify the Library
+subject to these terms and conditions.  You may not impose any further
+restrictions on the recipients' exercise of the rights granted herein.
+You are not responsible for enforcing compliance by third parties with
+this License.
+
+  11. If, as a consequence of a court judgment or allegation of patent
+infringement or for any other reason (not limited to patent issues),
+conditions are imposed on you (whether by court order, agreement or
+otherwise) that contradict the conditions of this License, they do not
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+the only way you could satisfy both it and this License would be to
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+
+If any portion of this section is held invalid or unenforceable under
+any particular circumstance, the balance of the section is intended to
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+
+This section is intended to make thoroughly clear what is believed to
+be a consequence of the rest of this License.
+
+  12. If the distribution and/or use of the Library is restricted in
+certain countries either by patents or by copyrighted interfaces, the
+original copyright holder who places the Library under this License
+may add an explicit geographical distribution limitation excluding those
+countries, so that distribution is permitted only in or among
+countries not thus excluded.  In such case, this License incorporates
+the limitation as if written in the body of this License.
+
+  13. The Free Software Foundation may publish revised and/or new
+versions of the Lesser General Public License from time to time.
+Such new versions will be similar in spirit to the present version,
+but may differ in detail to address new problems or concerns.
+
+Each version is given a distinguishing version number.  If the Library
+specifies a version number of this License which applies to it and
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+conditions either of that version or of any later version published by
+the Free Software Foundation.  If the Library does not specify a
+license version number, you may choose any version ever published by
+the Free Software Foundation.
+
+  14. If you wish to incorporate parts of the Library into other free
+programs whose distribution conditions are incompatible with these,
+write to the author to ask for permission.  For software which is
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+of all derivatives of our free software and of promoting the sharing
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+
+                            NO WARRANTY
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+  15. BECAUSE THE LIBRARY IS LICENSED FREE OF CHARGE, THERE IS NO
+WARRANTY FOR THE LIBRARY, TO THE EXTENT PERMITTED BY APPLICABLE LAW.
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+FAILURE OF THE LIBRARY TO OPERATE WITH ANY OTHER SOFTWARE), EVEN IF
+SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH
+DAMAGES.
+
+                     END OF TERMS AND CONDITIONS
+
+           How to Apply These Terms to Your New Libraries
+
+  If you develop a new library, and you want it to be of the greatest
+possible use to the public, we recommend making it free software that
+everyone can redistribute and change.  You can do so by permitting
+redistribution under these terms (or, alternatively, under the terms
+of the ordinary General Public License).
+
+  To apply these terms, attach the following notices to the library.
+It is safest to attach them to the start of each source file to most
+effectively convey the exclusion of warranty; and each file should
+have at least the "copyright" line and a pointer to where the full
+notice is found.
+
+
+    <one line to give the library's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This library is free software; you can redistribute it and/or
+    modify it under the terms of the GNU Lesser General Public
+    License as published by the Free Software Foundation; either
+    version 2.1 of the License, or (at your option) any later version.
+
+    This library is distributed in the hope that it will be useful,
+    but WITHOUT ANY WARRANTY; without even the implied warranty of
+    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+    Lesser General Public License for more details.
+
+    You should have received a copy of the GNU Lesser General Public
+    License along with this library; if not, write to the Free Software
+    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+
+Also add information on how to contact you by electronic and paper mail.
+
+You should also get your employer (if you work as a programmer) or
+your school, if any, to sign a "copyright disclaimer" for the library,
+if necessary.  Here is a sample; alter the names:
+
+  Yoyodyne, Inc., hereby disclaims all copyright interest in the
+  library `Frob' (a library for tweaking knobs) written by James
+  Random Hacker.
+
+  <signature of Ty Coon>, 1 April 1990
+  Ty Coon, President of Vice
+
+That's all there is to it!
diff --git a/lib/ccan/likely/_info b/lib/ccan/likely/_info
new file mode 100644
index 0000000000..471c1ffc78
--- /dev/null
+++ b/lib/ccan/likely/_info
@@ -0,0 +1,45 @@
+#include <string.h>
+#include <stdio.h>
+#include "config.h"
+
+/**
+ * likely - macros for annotating likely/unlikely branches in the code
+ *
+ * Inspired by Andi Kleen's macros for the Linux Kernel, these macros
+ * help you annotate rare paths in your code for the convenience of the
+ * compiler and the reader.
+ *
+ * License: LGPL (2 or any later version)
+ * Author: Rusty Russell <rusty@rustcorp.com.au>
+ *
+ * Example:
+ *	#include <ccan/likely/likely.h>
+ *	#include <stdio.h>
+ *
+ *	int main(int argc, char *argv[])
+ *	{
+ *		// This example is silly: the compiler knows exit() is unlikely.
+ *		if (unlikely(argc == 1)) {
+ *			fprintf(stderr, "Usage: %s <args>...\n", argv[0]);
+ *			return 1;
+ *		}
+ *		for (argc++; argv[argc]; argc++)
+ *			printf("%s\n", argv[argc]);
+ *		return 0;
+ *	}
+ */
+int main(int argc, char *argv[])
+{
+	/* Expect exactly one argument */
+	if (argc != 2)
+		return 1;
+
+	if (strcmp(argv[1], "depends") == 0) {
+		printf("ccan/str\n");
+		printf("ccan/htable\n");
+		printf("ccan/hash\n");
+		return 0;
+	}
+
+	return 1;
+}
diff --git a/lib/ccan/likely/likely.c b/lib/ccan/likely/likely.c
new file mode 100644
index 0000000000..8893d0b6d2
--- /dev/null
+++ b/lib/ccan/likely/likely.c
@@ -0,0 +1,141 @@
+#ifdef CCAN_LIKELY_DEBUG
+#include <ccan/likely/likely.h>
+#include <ccan/hash/hash.h>
+#include <ccan/htable/htable.h>
+#include <stdlib.h>
+#include <stdio.h>
+static struct htable *htable;
+
+struct trace {
+	const char *condstr;
+	const char *file;
+	unsigned int line;
+	bool expect;
+	unsigned long count, right;
+};
+
+/* We hash the pointers, which will be identical for same call. */
+static unsigned long hash_trace(const struct trace *trace)
+{
+	return hash_pointer(trace->condstr,
+			    hash_pointer(trace->file,
+					 trace->line + trace->expect));
+}
+
+static bool hash_cmp(const void *htelem, void *cmpdata)
+{
+	const struct trace *t1 = htelem, *t2 = cmpdata;
+	return t1->condstr == t2->condstr
+		&& t1->file == t2->file
+		&& t1->line == t2->line
+		&& t1->expect == t2->expect;
+}
+
+static size_t rehash(const void *elem, void *priv)
+{
+	return hash_trace(elem);
+}
+
+static void init_trace(struct trace *trace,
+		       const char *condstr, const char *file, unsigned int line,
+		       bool expect)
+{
+	trace->condstr = condstr;
+	trace->file = file;
+	trace->line = line;
+	trace->expect = expect;
+	trace->count = trace->right = 0;
+}
+
+static struct trace *add_trace(const char *condstr,
+			       const char *file, unsigned int line, bool expect)
+{
+	struct trace *trace = malloc(sizeof(*trace));
+	init_trace(trace, condstr, file, line, expect);
+	htable_add(htable, hash_trace(trace), trace);
+	return trace;
+}
+
+long _likely_trace(bool cond, bool expect,
+		   const char *condstr,
+		   const char *file, unsigned int line)
+{
+	struct trace *p, trace;
+
+	if (!htable)
+		htable = htable_new(rehash, NULL);
+
+	init_trace(&trace, condstr, file, line, expect);
+	p = htable_get(htable, hash_trace(&trace), hash_cmp, &trace);
+	if (!p)
+		p = add_trace(condstr, file, line, expect);
+
+	p->count++;
+	if (cond == expect)
+		p->right++;
+
+	return cond;
+}
+
+struct get_stats_info {
+	struct trace *worst;
+	unsigned int min_hits;
+	double worst_ratio;
+};
+
+static double right_ratio(const struct trace *t)
+{
+	return (double)t->right / t->count;
+}
+
+static void get_stats(struct trace *trace, struct get_stats_info *info)
+{
+	if (trace->count < info->min_hits)
+		return;
+
+	if (right_ratio(trace) < info->worst_ratio) {
+		info->worst = trace;
+		info->worst_ratio = right_ratio(trace);
+	}
+}
+
+const char *likely_stats(unsigned int min_hits, unsigned int percent)
+{
+	struct get_stats_info info;
+	struct htable_iter i;
+	char *ret;
+	struct trace *trace;
+
+	if (!htable)
+		return NULL;
+
+	info.min_hits = min_hits;
+	info.worst = NULL;
+	info.worst_ratio = 2;
+
+	/* This is O(n), but it's not likely called that often. */
+	for (trace = htable_first(htable, &i);
+	     trace;
+	     trace = htable_next(htable,&i)) {
+		get_stats(trace, &info);
+	}
+
+	if (info.worst_ratio * 100 > percent)
+		return NULL;
+
+	ret = malloc(strlen(info.worst->condstr) +
+		     strlen(info.worst->file) +
+		     sizeof(long int) * 8 +
+		     sizeof("%s:%u:%slikely(%s) correct %u%% (%lu/%lu)"));
+	sprintf(ret, "%s:%u:%slikely(%s) correct %u%% (%lu/%lu)",
+		info.worst->file, info.worst->line,
+		info.worst->expect ? "" : "un", info.worst->condstr,
+		(unsigned)(info.worst_ratio * 100),
+		info.worst->right, info.worst->count);
+
+	htable_del(htable, hash_trace(info.worst), info.worst);
+	free(info.worst);
+
+	return ret;
+}
+#endif /*CCAN_LIKELY_DEBUG*/
diff --git a/lib/ccan/likely/likely.h b/lib/ccan/likely/likely.h
new file mode 100644
index 0000000000..80d695c842
--- /dev/null
+++ b/lib/ccan/likely/likely.h
@@ -0,0 +1,105 @@
+#ifndef CCAN_LIKELY_H
+#define CCAN_LIKELY_H
+#include "config.h"
+#include <ccan/str/str.h>
+#include <stdbool.h>
+
+#ifndef CCAN_LIKELY_DEBUG
+#if HAVE_BUILTIN_EXPECT
+/**
+ * likely - indicate that a condition is likely to be true.
+ * @cond: the condition
+ *
+ * This uses a compiler extension where available to indicate a likely
+ * code path and optimize appropriately; it's also useful for readers
+ * to quickly identify exceptional paths through functions.  The
+ * threshold for "likely" is usually considered to be between 90 and
+ * 99%; marginal cases should not be marked either way.
+ *
+ * See Also:
+ *	unlikely(), likely_stats()
+ *
+ * Example:
+ *	// Returns false if we overflow.
+ *	static inline bool inc_int(unsigned int *val)
+ *	{
+ *		(*val)++;
+ *		if (likely(*val))
+ *			return true;
+ *		return false;
+ *	}
+ */
+#define likely(cond) __builtin_expect(!!(cond), 1)
+
+/**
+ * unlikely - indicate that a condition is unlikely to be true.
+ * @cond: the condition
+ *
+ * This uses a compiler extension where available to indicate an unlikely
+ * code path and optimize appropriately; see likely() above.
+ *
+ * See Also:
+ *	likely(), likely_stats(), COLD (compiler.h)
+ *
+ * Example:
+ *	// Prints a warning if we overflow.
+ *	static inline void inc_int(unsigned int *val)
+ *	{
+ *		(*val)++;
+ *		if (unlikely(*val == 0))
+ *			fprintf(stderr, "Overflow!");
+ *	}
+ */
+#define unlikely(cond) __builtin_expect(!!(cond), 0)
+#else
+#define likely(cond) (!!(cond))
+#define unlikely(cond) (!!(cond))
+#endif
+#else /* CCAN_LIKELY_DEBUG versions */
+#define likely(cond) \
+	(_likely_trace(!!(cond), 1, stringify(cond), __FILE__, __LINE__))
+#define unlikely(cond) \
+	(_likely_trace(!!(cond), 0, stringify(cond), __FILE__, __LINE__))
+
+long _likely_trace(bool cond, bool expect,
+		   const char *condstr,
+		   const char *file, unsigned int line);
+#endif
+
+#ifdef CCAN_LIKELY_DEBUG
+/**
+ * likely_stats - return description of abused likely()/unlikely()
+ * @min_hits: minimum number of hits
+ * @percent: maximum percentage correct
+ *
+ * When CCAN_LIKELY_DEBUG is defined, likely() and unlikely() trace their
+ * results: this causes a significant slowdown, but allows analysis of
+ * whether the branches are labelled correctly.
+ *
+ * This function returns a malloc'ed description of the least-correct
+ * usage of likely() or unlikely().  It ignores places which have been
+ * called less than @min_hits times, and those which were predicted
+ * correctly more than @percent of the time.  It returns NULL when
+ * nothing meets those criteria.
+ *
+ * Note that this call is destructive; the returned offender is
+ * removed from the trace so that the next call to likely_stats() will
+ * return the next-worst likely()/unlikely() usage.
+ *
+ * Example:
+ *	// Print every place hit more than twice which was wrong > 5%.
+ *	static void report_stats(void)
+ *	{
+ *	#ifdef CCAN_LIKELY_DEBUG
+ *		const char *bad;
+ *
+ *		while ((bad = likely_stats(2, 95)) != NULL) {
+ *			printf("Suspicious likely: %s", bad);
+ *			free(bad);
+ *		}
+ *	#endif
+ *	}
+ */
+const char *likely_stats(unsigned int min_hits, unsigned int percent);
+#endif /* CCAN_LIKELY_DEBUG */
+#endif /* CCAN_LIKELY_H */
diff --git a/lib/ccan/likely/test/run-debug.c b/lib/ccan/likely/test/run-debug.c
new file mode 100644
index 0000000000..df78619271
--- /dev/null
+++ b/lib/ccan/likely/test/run-debug.c
@@ -0,0 +1,87 @@
+#define CCAN_LIKELY_DEBUG 1
+#include <ccan/likely/likely.c>
+#include <ccan/likely/likely.h>
+#include <ccan/tap/tap.h>
+#include <stdlib.h>
+
+static bool one_seems_likely(unsigned int val)
+{
+	if (likely(val == 1))
+		return true;
+	return false;
+}
+
+static bool one_seems_unlikely(unsigned int val)
+{
+	if (unlikely(val == 1))
+		return true;
+	return false;
+}
+
+static bool likely_one_unlikely_two(unsigned int val1, unsigned int val2)
+{
+	/* Same line, check we don't get confused! */
+	if (likely(val1 == 1) && unlikely(val2 == 2))
+		return true;
+	return false;
+}
+
+int main(int argc, char *argv[])
+{
+	const char *bad;
+
+	plan_tests(13);
+
+	/* Correct guesses. */
+	one_seems_likely(1);
+	ok1(likely_stats(0, 90) == NULL);
+	one_seems_unlikely(2);
+	ok1(likely_stats(0, 90) == NULL);
+
+	/* Incorrect guesses. */
+	one_seems_likely(0);
+	one_seems_likely(2);
+	/* Hasn't been hit 4 times, so this fails */
+	ok1(!likely_stats(4, 90));
+	bad = likely_stats(3, 90);
+	ok(strends(bad, "run-debug.c:9:likely(val == 1) correct 33% (1/3)"),
+	   "likely_stats returned %s", bad);
+
+	/* Nothing else above 90% */
+	ok1(!likely_stats(0, 90));
+
+	/* This should get everything. */
+	bad = likely_stats(0, 100);
+	ok(strends(bad, "run-debug.c:16:unlikely(val == 1) correct 100% (1/1)"),
+	   "likely_stats returned %s", bad);
+
+	/* Nothing left (table is actually cleared) */
+	ok1(!likely_stats(0, 100));
+
+	/* Make sure unlikely works */
+	one_seems_unlikely(0);
+	one_seems_unlikely(2);
+	one_seems_unlikely(1);
+
+	bad = likely_stats(0, 90);
+	ok(strends(bad, "run-debug.c:16:unlikely(val == 1) correct 66% (2/3)"),
+	   "likely_stats returned %s", bad);
+	ok1(!likely_stats(0, 100));
+
+	likely_one_unlikely_two(1, 1);
+	likely_one_unlikely_two(1, 1);
+	likely_one_unlikely_two(1, 1);
+	ok1(!likely_stats(0, 90));
+	likely_one_unlikely_two(1, 2);
+
+	bad = likely_stats(0, 90);
+	ok(strends(bad, "run-debug.c:24:unlikely(val2 == 2) correct 75% (3/4)"),
+	   "likely_stats returned %s", bad);
+	bad = likely_stats(0, 100);
+	ok(strends(bad, "run-debug.c:24:likely(val1 == 1) correct 100% (4/4)"),
+	   "likely_stats returned %s", bad);
+
+	ok1(!likely_stats(0, 100));
+
+	exit(exit_status());
+}
diff --git a/lib/ccan/likely/test/run.c b/lib/ccan/likely/test/run.c
new file mode 100644
index 0000000000..fa1dc9f6ea
--- /dev/null
+++ b/lib/ccan/likely/test/run.c
@@ -0,0 +1,30 @@
+#include <ccan/likely/likely.c>
+#include <ccan/likely/likely.h>
+#include <ccan/tap/tap.h>
+#include <stdlib.h>
+
+static bool one_seems_likely(unsigned int val)
+{
+	if (likely(val == 1))
+		return true;
+	return false;
+}
+
+static bool one_seems_unlikely(unsigned int val)
+{
+	if (unlikely(val == 1))
+		return true;
+	return false;
+}
+
+int main(int argc, char *argv[])
+{
+	plan_tests(4);
+
+	/* Without debug, we can only check that it doesn't effect functions. */
+	ok1(one_seems_likely(1));
+	ok1(!one_seems_likely(2));
+	ok1(one_seems_unlikely(1));
+	ok1(!one_seems_unlikely(2));
+	exit(exit_status());
+}
diff --git a/lib/ccan/str/LICENSE b/lib/ccan/str/LICENSE
new file mode 100644
index 0000000000..5522aa5f33
--- /dev/null
+++ b/lib/ccan/str/LICENSE
@@ -0,0 +1,508 @@
+
+                  GNU LESSER GENERAL PUBLIC LICENSE
+                       Version 2.1, February 1999
+
+ Copyright (C) 1991, 1999 Free Software Foundation, Inc.
+	51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+[This is the first released version of the Lesser GPL.  It also counts
+ as the successor of the GNU Library Public License, version 2, hence
+ the version number 2.1.]
+
+                            Preamble
+
+  The licenses for most software are designed to take away your
+freedom to share and change it.  By contrast, the GNU General Public
+Licenses are intended to guarantee your freedom to share and change
+free software--to make sure the software is free for all its users.
+
+  This license, the Lesser General Public License, applies to some
+specially designated software packages--typically libraries--of the
+Free Software Foundation and other authors who decide to use it.  You
+can use it too, but we suggest you first think carefully about whether
+this license or the ordinary General Public License is the better
+strategy to use in any particular case, based on the explanations
+below.
+
+  When we speak of free software, we are referring to freedom of use,
+not price.  Our General Public Licenses are designed to make sure that
+you have the freedom to distribute copies of free software (and charge
+for this service if you wish); that you receive source code or can get
+it if you want it; that you can change the software and use pieces of
+it in new free programs; and that you are informed that you can do
+these things.
+
+  To protect your rights, we need to make restrictions that forbid
+distributors to deny you these rights or to ask you to surrender these
+rights.  These restrictions translate to certain responsibilities for
+you if you distribute copies of the library or if you modify it.
+
+  For example, if you distribute copies of the library, whether gratis
+or for a fee, you must give the recipients all the rights that we gave
+you.  You must make sure that they, too, receive or can get the source
+code.  If you link other code with the library, you must provide
+complete object files to the recipients, so that they can relink them
+with the library after making changes to the library and recompiling
+it.  And you must show them these terms so they know their rights.
+
+  We protect your rights with a two-step method: (1) we copyright the
+library, and (2) we offer you this license, which gives you legal
+permission to copy, distribute and/or modify the library.
+
+  To protect each distributor, we want to make it very clear that
+there is no warranty for the free library.  Also, if the library is
+modified by someone else and passed on, the recipients should know
+that what they have is not the original version, so that the original
+author's reputation will not be affected by problems that might be
+introduced by others.
+
+  Finally, software patents pose a constant threat to the existence of
+any free program.  We wish to make sure that a company cannot
+effectively restrict the users of a free program by obtaining a
+restrictive license from a patent holder.  Therefore, we insist that
+any patent license obtained for a version of the library must be
+consistent with the full freedom of use specified in this license.
+
+  Most GNU software, including some libraries, is covered by the
+ordinary GNU General Public License.  This license, the GNU Lesser
+General Public License, applies to certain designated libraries, and
+is quite different from the ordinary General Public License.  We use
+this license for certain libraries in order to permit linking those
+libraries into non-free programs.
+
+  When a program is linked with a library, whether statically or using
+a shared library, the combination of the two is legally speaking a
+combined work, a derivative of the original library.  The ordinary
+General Public License therefore permits such linking only if the
+entire combination fits its criteria of freedom.  The Lesser General
+Public License permits more lax criteria for linking other code with
+the library.
+
+  We call this license the "Lesser" General Public License because it
+does Less to protect the user's freedom than the ordinary General
+Public License.  It also provides other free software developers Less
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diff --git a/lib/ccan/str/_info b/lib/ccan/str/_info
new file mode 100644
index 0000000000..ea314dbf79
--- /dev/null
+++ b/lib/ccan/str/_info
@@ -0,0 +1,52 @@
+#include <stdio.h>
+#include <string.h>
+#include "config.h"
+
+/**
+ * str - string helper routines
+ *
+ * This is a grab bag of functions for string operations, designed to enhance
+ * the standard string.h.
+ *
+ * Note that if you define CCAN_STR_DEBUG, you will get extra compile
+ * checks on common misuses of the following functions (they will now
+ * be out-of-line, so there is a runtime penalty!).
+ *
+ *	strstr, strchr, strrchr:
+ *		Return const char * if first argument is const (gcc only).
+ *
+ *	isalnum, isalpha, isascii, isblank, iscntrl, isdigit, isgraph,
+ *	    islower, isprint, ispunct, isspace, isupper, isxdigit:
+ *		Static and runtime check that input is EOF or an *unsigned*
+ *		char, as per C standard (really!).
+ *
+ * Example:
+ *	#include <stdio.h>
+ *	#include <ccan/str/str.h>
+ *
+ *	int main(int argc, char *argv[])
+ *	{
+ *		if (argv[1] && streq(argv[1], "--verbose"))
+ *			printf("verbose set\n");
+ *		if (argv[1] && strstarts(argv[1], "--"))
+ *			printf("Some option set\n");
+ *		if (argv[1] && strends(argv[1], "cow-powers"))
+ *			printf("Magic option set\n");
+ *		return 0;
+ *	}
+ *
+ * License: LGPL (2 or any later version)
+ * Author: Rusty Russell <rusty@rustcorp.com.au>
+ */
+int main(int argc, char *argv[])
+{
+	if (argc != 2)
+		return 1;
+
+	if (strcmp(argv[1], "depends") == 0) {
+		printf("ccan/build_assert\n");
+		return 0;
+	}
+
+	return 1;
+}
diff --git a/lib/ccan/str/debug.c b/lib/ccan/str/debug.c
new file mode 100644
index 0000000000..9ef756766a
--- /dev/null
+++ b/lib/ccan/str/debug.c
@@ -0,0 +1,104 @@
+#include "config.h"
+#include <ccan/str/str_debug.h>
+#include <assert.h>
+#include <ctype.h>
+#include <string.h>
+
+#ifdef CCAN_STR_DEBUG
+/* Because we mug the real ones with macros, we need our own wrappers. */
+int str_isalnum(int i)
+{
+	assert(i >= -1 && i < 256);
+	return isalnum(i);
+}
+
+int str_isalpha(int i)
+{
+	assert(i >= -1 && i < 256);
+	return isalpha(i);
+}
+
+int str_isascii(int i)
+{
+	assert(i >= -1 && i < 256);
+	return isascii(i);
+}
+
+#if HAVE_ISBLANK
+int str_isblank(int i)
+{
+	assert(i >= -1 && i < 256);
+	return isblank(i);
+}
+#endif
+
+int str_iscntrl(int i)
+{
+	assert(i >= -1 && i < 256);
+	return iscntrl(i);
+}
+
+int str_isdigit(int i)
+{
+	assert(i >= -1 && i < 256);
+	return isdigit(i);
+}
+
+int str_isgraph(int i)
+{
+	assert(i >= -1 && i < 256);
+	return isgraph(i);
+}
+
+int str_islower(int i)
+{
+	assert(i >= -1 && i < 256);
+	return islower(i);
+}
+
+int str_isprint(int i)
+{
+	assert(i >= -1 && i < 256);
+	return isprint(i);
+}
+
+int str_ispunct(int i)
+{
+	assert(i >= -1 && i < 256);
+	return ispunct(i);
+}
+
+int str_isspace(int i)
+{
+	assert(i >= -1 && i < 256);
+	return isspace(i);
+}
+
+int str_isupper(int i)
+{
+	assert(i >= -1 && i < 256);
+	return isupper(i);
+}
+
+int str_isxdigit(int i)
+{
+	assert(i >= -1 && i < 256);
+	return isxdigit(i);
+}
+
+
+char *str_strstr(const char *haystack, const char *needle)
+{
+	return strstr(haystack, needle);
+}
+
+char *str_strchr(const char *haystack, int c)
+{
+	return strchr(haystack, c);
+}
+
+char *str_strrchr(const char *haystack, int c)
+{
+	return strrchr(haystack, c);
+}
+#endif
diff --git a/lib/ccan/str/str.c b/lib/ccan/str/str.c
new file mode 100644
index 0000000000..fa9809fbd9
--- /dev/null
+++ b/lib/ccan/str/str.c
@@ -0,0 +1,12 @@
+#include <ccan/str/str.h>
+
+size_t strcount(const char *haystack, const char *needle)
+{
+	size_t i = 0, nlen = strlen(needle);
+
+	while ((haystack = strstr(haystack, needle)) != NULL) {
+		i++;
+		haystack += nlen;
+	}
+	return i;
+}
diff --git a/lib/ccan/str/str.h b/lib/ccan/str/str.h
new file mode 100644
index 0000000000..ae51cdcc99
--- /dev/null
+++ b/lib/ccan/str/str.h
@@ -0,0 +1,200 @@
+#ifndef CCAN_STR_H
+#define CCAN_STR_H
+#include "config.h"
+#include <string.h>
+#include <stdbool.h>
+#include <ctype.h>
+
+/**
+ * streq - Are two strings equal?
+ * @a: first string
+ * @b: first string
+ *
+ * This macro is arguably more readable than "!strcmp(a, b)".
+ *
+ * Example:
+ *	if (streq(somestring, ""))
+ *		printf("String is empty!\n");
+ */
+#define streq(a,b) (strcmp((a),(b)) == 0)
+
+/**
+ * strstarts - Does this string start with this prefix?
+ * @str: string to test
+ * @prefix: prefix to look for at start of str
+ *
+ * Example:
+ *	if (strstarts(somestring, "foo"))
+ *		printf("String %s begins with 'foo'!\n", somestring);
+ */
+#define strstarts(str,prefix) (strncmp((str),(prefix),strlen(prefix)) == 0)
+
+/**
+ * strends - Does this string end with this postfix?
+ * @str: string to test
+ * @postfix: postfix to look for at end of str
+ *
+ * Example:
+ *	if (strends(somestring, "foo"))
+ *		printf("String %s end with 'foo'!\n", somestring);
+ */
+static inline bool strends(const char *str, const char *postfix)
+{
+	if (strlen(str) < strlen(postfix))
+		return false;
+
+	return streq(str + strlen(str) - strlen(postfix), postfix);
+}
+
+/**
+ * stringify - Turn expression into a string literal
+ * @expr: any C expression
+ *
+ * Example:
+ *	#define PRINT_COND_IF_FALSE(cond) \
+ *		((cond) || printf("%s is false!", stringify(cond)))
+ */
+#define stringify(expr)		stringify_1(expr)
+/* Double-indirection required to stringify expansions */
+#define stringify_1(expr)	#expr
+
+/**
+ * strcount - Count number of (non-overlapping) occurrences of a substring.
+ * @haystack: a C string
+ * @needle: a substring
+ *
+ * Example:
+ *	int i;
+ *      i = strcount("aaa aaa", "a");  // i = 6;
+ *      i = strcount("aaa aaa", "ab"); // i = 0;
+ *      i = strcount("aaa aaa", "aa"); // i = 2;
+ */
+size_t strcount(const char *haystack, const char *needle);
+
+/**
+ * cisalnum - isalnum() which takes a char (and doesn't accept EOF)
+ * @c: a character
+ *
+ * Surprisingly, the standard ctype.h isalnum() takes an int, which
+ * must have the value of EOF (-1) or an unsigned char.  This variant
+ * takes a real char, and doesn't accept EOF.
+ */
+static inline bool cisalnum(char c)
+{
+	return isalnum((unsigned char)c);
+}
+static inline bool cisalpha(char c)
+{
+	return isalpha((unsigned char)c);
+}
+static inline bool cisascii(char c)
+{
+	return isascii((unsigned char)c);
+}
+#if HAVE_ISBLANK
+static inline bool cisblank(char c)
+{
+	return isblank((unsigned char)c);
+}
+#endif
+static inline bool ciscntrl(char c)
+{
+	return iscntrl((unsigned char)c);
+}
+static inline bool cisdigit(char c)
+{
+	return isdigit((unsigned char)c);
+}
+static inline bool cisgraph(char c)
+{
+	return isgraph((unsigned char)c);
+}
+static inline bool cislower(char c)
+{
+	return islower((unsigned char)c);
+}
+static inline bool cisprint(char c)
+{
+	return isprint((unsigned char)c);
+}
+static inline bool cispunct(char c)
+{
+	return ispunct((unsigned char)c);
+}
+static inline bool cisspace(char c)
+{
+	return isspace((unsigned char)c);
+}
+static inline bool cisupper(char c)
+{
+	return isupper((unsigned char)c);
+}
+static inline bool cisxdigit(char c)
+{
+	return isxdigit((unsigned char)c);
+}
+
+#include <ccan/str/str_debug.h>
+
+/* These checks force things out of line, hence they are under DEBUG. */
+#ifdef CCAN_STR_DEBUG
+#include <ccan/build_assert/build_assert.h>
+
+/* These are commonly misused: they take -1 or an *unsigned* char value. */
+#undef isalnum
+#undef isalpha
+#undef isascii
+#undef isblank
+#undef iscntrl
+#undef isdigit
+#undef isgraph
+#undef islower
+#undef isprint
+#undef ispunct
+#undef isspace
+#undef isupper
+#undef isxdigit
+
+/* You can use a char if char is unsigned. */
+#if HAVE_BUILTIN_TYPES_COMPATIBLE_P && HAVE_TYPEOF
+#define str_check_arg_(i)						\
+	((i) + BUILD_ASSERT_OR_ZERO(!__builtin_types_compatible_p(typeof(i), \
+								  char)	\
+				    || (char)255 > 0))
+#else
+#define str_check_arg_(i) (i)
+#endif
+
+#define isalnum(i) str_isalnum(str_check_arg_(i))
+#define isalpha(i) str_isalpha(str_check_arg_(i))
+#define isascii(i) str_isascii(str_check_arg_(i))
+#if HAVE_ISBLANK
+#define isblank(i) str_isblank(str_check_arg_(i))
+#endif
+#define iscntrl(i) str_iscntrl(str_check_arg_(i))
+#define isdigit(i) str_isdigit(str_check_arg_(i))
+#define isgraph(i) str_isgraph(str_check_arg_(i))
+#define islower(i) str_islower(str_check_arg_(i))
+#define isprint(i) str_isprint(str_check_arg_(i))
+#define ispunct(i) str_ispunct(str_check_arg_(i))
+#define isspace(i) str_isspace(str_check_arg_(i))
+#define isupper(i) str_isupper(str_check_arg_(i))
+#define isxdigit(i) str_isxdigit(str_check_arg_(i))
+
+#if HAVE_TYPEOF
+/* With GNU magic, we can make const-respecting standard string functions. */
+#undef strstr
+#undef strchr
+#undef strrchr
+
+/* + 0 is needed to decay array into pointer. */
+#define strstr(haystack, needle)					\
+	((typeof((haystack) + 0))str_strstr((haystack), (needle)))
+#define strchr(haystack, c)					\
+	((typeof((haystack) + 0))str_strchr((haystack), (c)))
+#define strrchr(haystack, c)					\
+	((typeof((haystack) + 0))str_strrchr((haystack), (c)))
+#endif
+#endif /* CCAN_STR_DEBUG */
+
+#endif /* CCAN_STR_H */
diff --git a/lib/ccan/str/str_debug.h b/lib/ccan/str/str_debug.h
new file mode 100644
index 0000000000..6b56477689
--- /dev/null
+++ b/lib/ccan/str/str_debug.h
@@ -0,0 +1,29 @@
+#ifndef CCAN_STR_DEBUG_H
+#define CCAN_STR_DEBUG_H
+
+/* #define CCAN_STR_DEBUG 1 */
+
+#ifdef CCAN_STR_DEBUG
+/* Because we mug the real ones with macros, we need our own wrappers. */
+int str_isalnum(int i);
+int str_isalpha(int i);
+int str_isascii(int i);
+#if HAVE_ISBLANK
+int str_isblank(int i);
+#endif
+int str_iscntrl(int i);
+int str_isdigit(int i);
+int str_isgraph(int i);
+int str_islower(int i);
+int str_isprint(int i);
+int str_ispunct(int i);
+int str_isspace(int i);
+int str_isupper(int i);
+int str_isxdigit(int i);
+
+char *str_strstr(const char *haystack, const char *needle);
+char *str_strchr(const char *s, int c);
+char *str_strrchr(const char *s, int c);
+#endif /* CCAN_STR_DEBUG */
+
+#endif /* CCAN_STR_DEBUG_H */
diff --git a/lib/ccan/str/test/compile_fail-isalnum.c b/lib/ccan/str/test/compile_fail-isalnum.c
new file mode 100644
index 0000000000..930defffa0
--- /dev/null
+++ b/lib/ccan/str/test/compile_fail-isalnum.c
@@ -0,0 +1,22 @@
+#define CCAN_STR_DEBUG 1
+#include <ccan/str/str.h>
+
+int main(int argc, char *argv[])
+{
+#ifdef FAIL
+#if !HAVE_BUILTIN_TYPES_COMPATIBLE_P || !HAVE_TYPEOF
+#error We need typeof to check isalnum.
+#endif
+	char
+#else
+	unsigned char
+#endif
+		c = argv[0][0];
+
+#ifdef FAIL
+	/* Fake fail on unsigned char platforms. */
+	BUILD_ASSERT((char)255 < 0);
+#endif
+
+	return isalnum(c);
+}
diff --git a/lib/ccan/str/test/compile_fail-isalpha.c b/lib/ccan/str/test/compile_fail-isalpha.c
new file mode 100644
index 0000000000..2005109829
--- /dev/null
+++ b/lib/ccan/str/test/compile_fail-isalpha.c
@@ -0,0 +1,22 @@
+#define CCAN_STR_DEBUG 1
+#include <ccan/str/str.h>
+
+int main(int argc, char *argv[])
+{
+#ifdef FAIL
+#if !HAVE_BUILTIN_TYPES_COMPATIBLE_P || !HAVE_TYPEOF
+#error We need typeof to check isalpha.
+#endif
+	char
+#else
+	unsigned char
+#endif
+		c = argv[0][0];
+
+#ifdef FAIL
+	/* Fake fail on unsigned char platforms. */
+	BUILD_ASSERT((char)255 < 0);
+#endif
+
+	return isalpha(c);
+}
diff --git a/lib/ccan/str/test/compile_fail-isascii.c b/lib/ccan/str/test/compile_fail-isascii.c
new file mode 100644
index 0000000000..ee55e49974
--- /dev/null
+++ b/lib/ccan/str/test/compile_fail-isascii.c
@@ -0,0 +1,22 @@
+#define CCAN_STR_DEBUG 1
+#include <ccan/str/str.h>
+
+int main(int argc, char *argv[])
+{
+#ifdef FAIL
+#if !HAVE_BUILTIN_TYPES_COMPATIBLE_P || !HAVE_TYPEOF
+#error We need typeof to check isascii.
+#endif
+	char
+#else
+	unsigned char
+#endif
+		c = argv[0][0];
+
+#ifdef FAIL
+	/* Fake fail on unsigned char platforms. */
+	BUILD_ASSERT((char)255 < 0);
+#endif
+
+	return isascii(c);
+}
diff --git a/lib/ccan/str/test/compile_fail-isblank.c b/lib/ccan/str/test/compile_fail-isblank.c
new file mode 100644
index 0000000000..f4cb961d74
--- /dev/null
+++ b/lib/ccan/str/test/compile_fail-isblank.c
@@ -0,0 +1,26 @@
+#define CCAN_STR_DEBUG 1
+#include <ccan/str/str.h>
+
+int main(int argc, char *argv[])
+{
+#ifdef FAIL
+#if !HAVE_BUILTIN_TYPES_COMPATIBLE_P || !HAVE_TYPEOF || !HAVE_ISBLANK
+#error We need typeof to check isblank.
+#endif
+	char
+#else
+	unsigned char
+#endif
+		c = argv[0][0];
+
+#ifdef FAIL
+	/* Fake fail on unsigned char platforms. */
+	BUILD_ASSERT((char)255 < 0);
+#endif
+
+#if HAVE_ISBLANK
+	return isblank(c);
+#else
+	return c;
+#endif
+}
diff --git a/lib/ccan/str/test/compile_fail-iscntrl.c b/lib/ccan/str/test/compile_fail-iscntrl.c
new file mode 100644
index 0000000000..bc74146542
--- /dev/null
+++ b/lib/ccan/str/test/compile_fail-iscntrl.c
@@ -0,0 +1,22 @@
+#define CCAN_STR_DEBUG 1
+#include <ccan/str/str.h>
+
+int main(int argc, char *argv[])
+{
+#ifdef FAIL
+#if !HAVE_BUILTIN_TYPES_COMPATIBLE_P || !HAVE_TYPEOF
+#error We need typeof to check iscntrl.
+#endif
+	char
+#else
+	unsigned char
+#endif
+		c = argv[0][0];
+
+#ifdef FAIL
+	/* Fake fail on unsigned char platforms. */
+	BUILD_ASSERT((char)255 < 0);
+#endif
+
+	return iscntrl(c);
+}
diff --git a/lib/ccan/str/test/compile_fail-isdigit.c b/lib/ccan/str/test/compile_fail-isdigit.c
new file mode 100644
index 0000000000..71d1c71433
--- /dev/null
+++ b/lib/ccan/str/test/compile_fail-isdigit.c
@@ -0,0 +1,22 @@
+#define CCAN_STR_DEBUG 1
+#include <ccan/str/str.h>
+
+int main(int argc, char *argv[])
+{
+#ifdef FAIL
+#if !HAVE_BUILTIN_TYPES_COMPATIBLE_P || !HAVE_TYPEOF
+#error We need typeof to check isdigit.
+#endif
+	char
+#else
+	unsigned char
+#endif
+		c = argv[0][0];
+
+#ifdef FAIL
+	/* Fake fail on unsigned char platforms. */
+	BUILD_ASSERT((char)255 < 0);
+#endif
+
+	return isdigit(c);
+}
diff --git a/lib/ccan/str/test/compile_fail-islower.c b/lib/ccan/str/test/compile_fail-islower.c
new file mode 100644
index 0000000000..ca3f9907e5
--- /dev/null
+++ b/lib/ccan/str/test/compile_fail-islower.c
@@ -0,0 +1,22 @@
+#define CCAN_STR_DEBUG 1
+#include <ccan/str/str.h>
+
+int main(int argc, char *argv[])
+{
+#ifdef FAIL
+#if !HAVE_BUILTIN_TYPES_COMPATIBLE_P || !HAVE_TYPEOF
+#error We need typeof to check islower.
+#endif
+	char
+#else
+	unsigned char
+#endif
+		c = argv[0][0];
+
+#ifdef FAIL
+	/* Fake fail on unsigned char platforms. */
+	BUILD_ASSERT((char)255 < 0);
+#endif
+
+	return islower(c);
+}
diff --git a/lib/ccan/str/test/compile_fail-isprint.c b/lib/ccan/str/test/compile_fail-isprint.c
new file mode 100644
index 0000000000..6432e41d2b
--- /dev/null
+++ b/lib/ccan/str/test/compile_fail-isprint.c
@@ -0,0 +1,22 @@
+#define CCAN_STR_DEBUG 1
+#include <ccan/str/str.h>
+
+int main(int argc, char *argv[])
+{
+#ifdef FAIL
+#if !HAVE_BUILTIN_TYPES_COMPATIBLE_P || !HAVE_TYPEOF
+#error We need typeof to check isprint.
+#endif
+	char
+#else
+	unsigned char
+#endif
+		c = argv[0][0];
+
+#ifdef FAIL
+	/* Fake fail on unsigned char platforms. */
+	BUILD_ASSERT((char)255 < 0);
+#endif
+
+	return isprint(c);
+}
diff --git a/lib/ccan/str/test/compile_fail-ispunct.c b/lib/ccan/str/test/compile_fail-ispunct.c
new file mode 100644
index 0000000000..5d941fcba6
--- /dev/null
+++ b/lib/ccan/str/test/compile_fail-ispunct.c
@@ -0,0 +1,22 @@
+#define CCAN_STR_DEBUG 1
+#include <ccan/str/str.h>
+
+int main(int argc, char *argv[])
+{
+#ifdef FAIL
+#if !HAVE_BUILTIN_TYPES_COMPATIBLE_P || !HAVE_TYPEOF
+#error We need typeof to check ispunct.
+#endif
+	char
+#else
+	unsigned char
+#endif
+		c = argv[0][0];
+
+#ifdef FAIL
+	/* Fake fail on unsigned char platforms. */
+	BUILD_ASSERT((char)255 < 0);
+#endif
+
+	return ispunct(c);
+}
diff --git a/lib/ccan/str/test/compile_fail-isspace.c b/lib/ccan/str/test/compile_fail-isspace.c
new file mode 100644
index 0000000000..bfee1f89f1
--- /dev/null
+++ b/lib/ccan/str/test/compile_fail-isspace.c
@@ -0,0 +1,22 @@
+#define CCAN_STR_DEBUG 1
+#include <ccan/str/str.h>
+
+int main(int argc, char *argv[])
+{
+#ifdef FAIL
+#if !HAVE_BUILTIN_TYPES_COMPATIBLE_P || !HAVE_TYPEOF
+#error We need typeof to check isspace.
+#endif
+	char
+#else
+	unsigned char
+#endif
+		c = argv[0][0];
+
+#ifdef FAIL
+	/* Fake fail on unsigned char platforms. */
+	BUILD_ASSERT((char)255 < 0);
+#endif
+
+	return isspace(c);
+}
diff --git a/lib/ccan/str/test/compile_fail-isupper.c b/lib/ccan/str/test/compile_fail-isupper.c
new file mode 100644
index 0000000000..4cf9fd3578
--- /dev/null
+++ b/lib/ccan/str/test/compile_fail-isupper.c
@@ -0,0 +1,22 @@
+#define CCAN_STR_DEBUG 1
+#include <ccan/str/str.h>
+
+int main(int argc, char *argv[])
+{
+#ifdef FAIL
+#if !HAVE_BUILTIN_TYPES_COMPATIBLE_P || !HAVE_TYPEOF
+#error We need typeof to check isupper.
+#endif
+	char
+#else
+	unsigned char
+#endif
+		c = argv[0][0];
+
+#ifdef FAIL
+	/* Fake fail on unsigned char platforms. */
+	BUILD_ASSERT((char)255 < 0);
+#endif
+
+	return isupper(c);
+}
diff --git a/lib/ccan/str/test/compile_fail-isxdigit.c b/lib/ccan/str/test/compile_fail-isxdigit.c
new file mode 100644
index 0000000000..65e6006a88
--- /dev/null
+++ b/lib/ccan/str/test/compile_fail-isxdigit.c
@@ -0,0 +1,22 @@
+#define CCAN_STR_DEBUG 1
+#include <ccan/str/str.h>
+
+int main(int argc, char *argv[])
+{
+#ifdef FAIL
+#if !HAVE_BUILTIN_TYPES_COMPATIBLE_P || !HAVE_TYPEOF
+#error We need typeof to check isxdigit.
+#endif
+	char
+#else
+	unsigned char
+#endif
+		c = argv[0][0];
+
+#ifdef FAIL
+	/* Fake fail on unsigned char platforms. */
+	BUILD_ASSERT((char)255 < 0);
+#endif
+
+	return isxdigit(c);
+}
diff --git a/lib/ccan/str/test/compile_fail-strchr.c b/lib/ccan/str/test/compile_fail-strchr.c
new file mode 100644
index 0000000000..74a7314d06
--- /dev/null
+++ b/lib/ccan/str/test/compile_fail-strchr.c
@@ -0,0 +1,18 @@
+#define CCAN_STR_DEBUG 1
+#include <ccan/str/str.h>
+
+int main(int argc, char *argv[])
+{
+#ifdef FAIL
+#if !HAVE_TYPEOF
+	#error We need typeof to check strstr.
+#endif
+#else
+	const
+#endif
+		char *ret;
+	const char *str = "hello";
+
+	ret = strchr(str, 'l');
+	return ret ? 0 : 1;
+}
diff --git a/lib/ccan/str/test/compile_fail-strrchr.c b/lib/ccan/str/test/compile_fail-strrchr.c
new file mode 100644
index 0000000000..ba7d17e031
--- /dev/null
+++ b/lib/ccan/str/test/compile_fail-strrchr.c
@@ -0,0 +1,18 @@
+#define CCAN_STR_DEBUG 1
+#include <ccan/str/str.h>
+
+int main(int argc, char *argv[])
+{
+#ifdef FAIL
+#if !HAVE_TYPEOF
+	#error We need typeof to check strstr.
+#endif
+#else
+	const
+#endif
+		char *ret;
+	const char *str = "hello";
+
+	ret = strrchr(str, 'l');
+	return ret ? 0 : 1;
+}
diff --git a/lib/ccan/str/test/compile_fail-strstr.c b/lib/ccan/str/test/compile_fail-strstr.c
new file mode 100644
index 0000000000..deefef6542
--- /dev/null
+++ b/lib/ccan/str/test/compile_fail-strstr.c
@@ -0,0 +1,18 @@
+#define CCAN_STR_DEBUG 1
+#include <ccan/str/str.h>
+
+int main(int argc, char *argv[])
+{
+#ifdef FAIL
+#if !HAVE_TYPEOF
+	#error We need typeof to check strstr.
+#endif
+#else
+	const
+#endif
+		char *ret;
+	const char *str = "hello";
+
+	ret = strstr(str, "hell");
+	return ret ? 0 : 1;
+}
diff --git a/lib/ccan/str/test/debug.c b/lib/ccan/str/test/debug.c
new file mode 100644
index 0000000000..4bd384f2c4
--- /dev/null
+++ b/lib/ccan/str/test/debug.c
@@ -0,0 +1,5 @@
+/* We can't use the normal "#include the .c file" trick, since this is
+   contaminated by str.h's macro overrides.  So we put it in all tests
+   like this. */
+#define CCAN_STR_DEBUG 1
+#include <ccan/str/debug.c>
diff --git a/lib/ccan/str/test/run.c b/lib/ccan/str/test/run.c
new file mode 100644
index 0000000000..a15654f8f3
--- /dev/null
+++ b/lib/ccan/str/test/run.c
@@ -0,0 +1,105 @@
+#include <ccan/str/str.h>
+#include <ccan/str/str.c>
+#include <stdlib.h>
+#include <stdio.h>
+#include <ccan/tap/tap.h>
+
+#define ARRAY_SIZE(arr) (sizeof(arr) / sizeof(arr[0]))
+
+static char *substrings[] = { "far", "bar", "baz", "b", "ba", "z", "ar", NULL };
+
+#define NUM_SUBSTRINGS (ARRAY_SIZE(substrings) - 1)
+
+static char *strdup_rev(const char *s)
+{
+	char *ret = strdup(s);
+	unsigned int i;
+
+	for (i = 0; i < strlen(s); i++)
+		ret[i] = s[strlen(s) - i - 1];
+	return ret;
+}
+
+int main(int argc, char *argv[])
+{
+	unsigned int i, j, n;
+	char *strings[NUM_SUBSTRINGS * NUM_SUBSTRINGS];
+
+	n = 0;
+	for (i = 0; i < NUM_SUBSTRINGS; i++) {
+		for (j = 0; j < NUM_SUBSTRINGS; j++) {
+			strings[n] = malloc(strlen(substrings[i])
+					    + strlen(substrings[j]) + 1);
+			sprintf(strings[n++], "%s%s",
+				substrings[i], substrings[j]);
+		}
+	}
+
+	plan_tests(n * n * 5 + 16);
+	for (i = 0; i < n; i++) {
+		for (j = 0; j < n; j++) {
+			unsigned int k, identical = 0;
+			char *reva, *revb;
+
+			/* Find first difference. */
+			for (k = 0; strings[i][k]==strings[j][k]; k++) {
+				if (k == strlen(strings[i])) {
+					identical = 1;
+					break;
+				}
+			}
+
+			if (identical)
+				ok1(streq(strings[i], strings[j]));
+			else
+				ok1(!streq(strings[i], strings[j]));
+
+			/* Postfix test should be equivalent to prefix
+			 * test on reversed string. */
+			reva = strdup_rev(strings[i]);
+			revb = strdup_rev(strings[j]);
+
+			if (!strings[i][k]) {
+				ok1(strstarts(strings[j], strings[i]));
+				ok1(strends(revb, reva));
+			} else {
+				ok1(!strstarts(strings[j], strings[i]));
+				ok1(!strends(revb, reva));
+			}
+			if (!strings[j][k]) {
+				ok1(strstarts(strings[i], strings[j]));
+				ok1(strends(reva, revb));
+			} else {
+				ok1(!strstarts(strings[i], strings[j]));
+				ok1(!strends(reva, revb));
+			}
+			free(reva);
+			free(revb);
+		}
+	}
+
+	for (i = 0; i < n; i++)
+		free(strings[i]);
+
+	ok1(streq(stringify(NUM_SUBSTRINGS),
+		  "((sizeof(substrings) / sizeof(substrings[0])) - 1)"));
+	ok1(streq(stringify(ARRAY_SIZE(substrings)),
+		  "(sizeof(substrings) / sizeof(substrings[0]))"));
+	ok1(streq(stringify(i == 0), "i == 0"));
+
+	ok1(strcount("aaaaaa", "b") == 0);
+	ok1(strcount("aaaaaa", "a") == 6);
+	ok1(strcount("aaaaaa", "aa") == 3);
+	ok1(strcount("aaaaaa", "aaa") == 2);
+	ok1(strcount("aaaaaa", "aaaa") == 1);
+	ok1(strcount("aaaaaa", "aaaaa") == 1);
+	ok1(strcount("aaaaaa", "aaaaaa") == 1);
+	ok1(strcount("aaa aaa", "b") == 0);
+	ok1(strcount("aaa aaa", "a") == 6);
+	ok1(strcount("aaa aaa", "aa") == 2);
+	ok1(strcount("aaa aaa", "aaa") == 2);
+	ok1(strcount("aaa aaa", "aaaa") == 0);
+	ok1(strcount("aaa aaa", "aaaaa") == 0);
+
+	return exit_status();
+}
diff --git a/lib/ccan/tally/LICENSE b/lib/ccan/tally/LICENSE
new file mode 100644
index 0000000000..cca7fc278f
--- /dev/null
+++ b/lib/ccan/tally/LICENSE
@@ -0,0 +1,165 @@
+		   GNU LESSER GENERAL PUBLIC LICENSE
+                       Version 3, 29 June 2007
+
+ Copyright (C) 2007 Free Software Foundation, Inc. <http://fsf.org/>
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+
+  This version of the GNU Lesser General Public License incorporates
+the terms and conditions of version 3 of the GNU General Public
+License, supplemented by the additional permissions listed below.
+
+  0. Additional Definitions.
+
+  As used herein, "this License" refers to version 3 of the GNU Lesser
+General Public License, and the "GNU GPL" refers to version 3 of the GNU
+General Public License.
+
+  "The Library" refers to a covered work governed by this License,
+other than an Application or a Combined Work as defined below.
+
+  An "Application" is any work that makes use of an interface provided
+by the Library, but which is not otherwise based on the Library.
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+with which the Combined Work was made is also called the "Linked
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+for portions of the Combined Work that, considered in isolation, are
+based on the Application, and not on the Linked Version.
+
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+object code and/or source code for the Application, including any data
+and utility programs needed for reproducing the Combined Work from the
+Application, but excluding the System Libraries of the Combined Work.
+
+  1. Exception to Section 3 of the GNU GPL.
+
+  You may convey a covered work under sections 3 and 4 of this License
+without being bound by section 3 of the GNU GPL.
+
+  2. Conveying Modified Versions.
+
+  If you modify a copy of the Library, and, in your modifications, a
+facility refers to a function or data to be supplied by an Application
+that uses the facility (other than as an argument passed when the
+facility is invoked), then you may convey a copy of the modified
+version:
+
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+   function or data, the facility still operates, and performs
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+
+   b) under the GNU GPL, with none of the additional permissions of
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+
+  3. Object Code Incorporating Material from Library Header Files.
+
+  The object code form of an Application may incorporate material from
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+(ten or fewer lines in length), you do both of the following:
+
+   a) Give prominent notice with each copy of the object code that the
+   Library is used in it and that the Library and its use are
+   covered by this License.
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+   b) Accompany the object code with a copy of the GNU GPL and this license
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+  4. Combined Works.
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+  You may convey a Combined Work under terms of your choice that,
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+   a) Give prominent notice with each copy of the Combined Work that
+   the Library is used in it and that the Library and its use are
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+   c) For a Combined Work that displays copyright notices during
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+   e) Provide Installation Information, but only if you would otherwise
+   be required to provide such information under section 6 of the
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+choice, if you do both of the following:
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+   a) Accompany the combined library with a copy of the same work based
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+  6. Revised Versions of the GNU Lesser General Public License.
+
+  The Free Software Foundation may publish revised and/or new versions
+of the GNU Lesser General Public License from time to time. Such new
+versions will be similar in spirit to the present version, but may
+differ in detail to address new problems or concerns.
+
+  Each version is given a distinguishing version number. If the
+Library as you received it specifies that a certain numbered version
+of the GNU Lesser General Public License "or any later version"
+applies to it, you have the option of following the terms and
+conditions either of that published version or of any later version
+published by the Free Software Foundation. If the Library as you
+received it does not specify a version number of the GNU Lesser
+General Public License, you may choose any version of the GNU Lesser
+General Public License ever published by the Free Software Foundation.
+
+  If the Library as you received it specifies that a proxy can decide
+whether future versions of the GNU Lesser General Public License shall
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+permanent authorization for you to choose that version for the
+Library.
diff --git a/lib/ccan/tally/_info b/lib/ccan/tally/_info
new file mode 100644
index 0000000000..1d67274f5c
--- /dev/null
+++ b/lib/ccan/tally/_info
@@ -0,0 +1,58 @@
+#include <stdio.h>
+#include <string.h>
+#include "config.h"
+
+/**
+ * tally - running tally of integers
+ *
+ * The tally module implements simple analysis of a stream of integers.
+ * Numbers are fed in via tally_add(), and then the mean, median, mode and
+ * a histogram can be read out.
+ *
+ * Example:
+ *	#include <stdio.h>
+ *	#include <err.h>
+ *	#include <ccan/tally/tally.h>
+ *
+ *	int main(int argc, char *argv[])
+ *	{
+ *		struct tally *t;
+ *		unsigned int i;
+ *		size_t err;
+ *		ssize_t val;
+ *		char *histogram;
+ *
+ *		if (argc < 2)
+ *			errx(1, "Usage: %s <number>...\n", argv[0]);
+ *
+ *		t = tally_new(100);
+ *		for (i = 1; i < argc; i++)
+ *			tally_add(t, atol(argv[i]));
+ *
+ *		printf("Mean = %zi\n", tally_mean(t));
+ *		val = tally_approx_median(t, &err);
+ *		printf("Median = %zi (+/- %zu)\n", val, err);
+ *		val = tally_approx_mode(t, &err);
+ *		printf("Mode = %zi (+/- %zu)\n", val, err);
+ *		histogram = tally_histogram(t, 50, 10);
+ *		printf("Histogram:\n%s", histogram);
+ *		free(histogram);
+ *		return 0;
+ *	}
+ *
+ * License: LGPL (3 or any later version)
+ * Author: Rusty Russell <rusty@rustcorp.com.au>
+ */
+int main(int argc, char *argv[])
+{
+	if (argc != 2)
+		return 1;
+
+	if (strcmp(argv[1], "depends") == 0) {
+		printf("ccan/build_assert\n");
+		printf("ccan/likely\n");
+		return 0;
+	}
+
+	return 1;
+}
diff --git a/lib/ccan/tally/tally.c b/lib/ccan/tally/tally.c
new file mode 100644
index 0000000000..0d01907955
--- /dev/null
+++ b/lib/ccan/tally/tally.c
@@ -0,0 +1,490 @@
+#include "config.h"
+#include <ccan/tally/tally.h>
+#include <ccan/build_assert/build_assert.h>
+#include <ccan/likely/likely.h>
+#include <stdint.h>
+#include <limits.h>
+#include <string.h>
+#include <stdio.h>
+#include <assert.h>
+
+#define SIZET_BITS (sizeof(size_t)*CHAR_BIT)
+
+/* We use power of 2 steps.  I tried being tricky, but it got buggy. */
+struct tally {
+	ssize_t min, max;
+	size_t total[2];
+	/* This allows limited frequency analysis. */
+	unsigned buckets, step_bits;
+	size_t counts[1 /* Actually: [buckets] */ ];
+};
+
+struct tally *tally_new(unsigned buckets)
+{
+	struct tally *tally;
+
+	/* There is always 1 bucket. */
+	if (buckets == 0)
+		buckets = 1;
+
+	/* Check for overflow. */
+	if (buckets && SIZE_MAX / buckets < sizeof(tally->counts[0]))
+		return NULL;
+	tally = malloc(sizeof(*tally) + sizeof(tally->counts[0])*(buckets-1));
+	if (tally) {
+		tally->max = ((size_t)1 << (SIZET_BITS - 1));
+		tally->min = ~tally->max;
+		tally->total[0] = tally->total[1] = 0;
+		tally->buckets = buckets;
+		tally->step_bits = 0;
+		memset(tally->counts, 0, sizeof(tally->counts[0])*buckets);
+	}
+	return tally;
+}
+
+static unsigned bucket_of(ssize_t min, unsigned step_bits, ssize_t val)
+{
+	/* Don't over-shift. */
+	if (step_bits == SIZET_BITS)
+		return 0;
+	assert(step_bits < SIZET_BITS);
+	return (size_t)(val - min) >> step_bits;
+}
+
+/* Return the min value in bucket b. */
+static ssize_t bucket_min(ssize_t min, unsigned step_bits, unsigned b)
+{
+	/* Don't over-shift. */
+	if (step_bits == SIZET_BITS)
+		return min;
+	assert(step_bits < SIZET_BITS);
+	return min + ((ssize_t)b << step_bits);
+}
+
+/* Does shifting by this many bits truncate the number? */
+static bool shift_overflows(size_t num, unsigned bits)
+{
+	if (bits == 0)
+		return false;
+
+	return ((num << bits) >> 1) != (num << (bits - 1));
+}
+
+/* When min or max change, we may need to shuffle the frequency counts. */
+static void renormalize(struct tally *tally,
+			ssize_t new_min, ssize_t new_max)
+{
+	size_t range, spill;
+	unsigned int i, old_min;
+
+	/* Uninitialized?  Don't do anything... */
+	if (tally->max < tally->min)
+		goto update;
+
+	/* If we don't have sufficient range, increase step bits until
+	 * buckets cover entire range of ssize_t anyway. */
+	range = (new_max - new_min) + 1;
+	while (!shift_overflows(tally->buckets, tally->step_bits)
+	       && range > ((size_t)tally->buckets << tally->step_bits)) {
+		/* Collapse down. */
+		for (i = 1; i < tally->buckets; i++) {
+			tally->counts[i/2] += tally->counts[i];
+			tally->counts[i] = 0;
+		}
+		tally->step_bits++;
+	}
+
+	/* Now if minimum has dropped, move buckets up. */
+	old_min = bucket_of(new_min, tally->step_bits, tally->min);
+	memmove(tally->counts + old_min,
+		tally->counts,
+		sizeof(tally->counts[0]) * (tally->buckets - old_min));
+	memset(tally->counts, 0, sizeof(tally->counts[0]) * old_min);
+
+	/* If we moved boundaries, adjust buckets to that ratio. */
+	spill = (tally->min - new_min) % (1 << tally->step_bits);
+	for (i = 0; i < tally->buckets-1; i++) {
+		size_t adjust = (tally->counts[i] >> tally->step_bits) * spill;
+		tally->counts[i] -= adjust;
+		tally->counts[i+1] += adjust;
+	}
+
+update:
+	tally->min = new_min;
+	tally->max = new_max;
+}
+
+void tally_add(struct tally *tally, ssize_t val)
+{
+	ssize_t new_min = tally->min, new_max = tally->max;
+	bool need_renormalize = false;
+
+	if (val < tally->min) {
+		new_min = val;
+		need_renormalize = true;
+	}
+	if (val > tally->max) {
+		new_max = val;
+		need_renormalize = true;
+	}
+	if (need_renormalize)
+		renormalize(tally, new_min, new_max);
+
+	/* 128-bit arithmetic!  If we didn't want exact mean, we could just
+	 * pull it out of counts. */
+	if (val > 0 && tally->total[0] + val < tally->total[0])
+		tally->total[1]++;
+	else if (val < 0 && tally->total[0] + val > tally->total[0])
+		tally->total[1]--;
+	tally->total[0] += val;
+	tally->counts[bucket_of(tally->min, tally->step_bits, val)]++;
+}
+
+size_t tally_num(const struct tally *tally)
+{
+	size_t i, num = 0;
+	for (i = 0; i < tally->buckets; i++)
+		num += tally->counts[i];
+	return num;
+}
+
+ssize_t tally_min(const struct tally *tally)
+{
+	return tally->min;
+}
+
+ssize_t tally_max(const struct tally *tally)
+{
+	return tally->max;
+}
+
+/* FIXME: Own ccan module please! */
+static unsigned fls64(uint64_t val)
+{
+#if HAVE_BUILTIN_CLZL
+	if (val <= ULONG_MAX) {
+		/* This is significantly faster! */
+		return val ? sizeof(long) * CHAR_BIT - __builtin_clzl(val) : 0;
+	} else {
+#endif
+	uint64_t r = 64;
+
+	if (!val)
+		return 0;
+	if (!(val & 0xffffffff00000000ull)) {
+		val <<= 32;
+		r -= 32;
+	}
+	if (!(val & 0xffff000000000000ull)) {
+		val <<= 16;
+		r -= 16;
+	}
+	if (!(val & 0xff00000000000000ull)) {
+		val <<= 8;
+		r -= 8;
+	}
+	if (!(val & 0xf000000000000000ull)) {
+		val <<= 4;
+		r -= 4;
+	}
+	if (!(val & 0xc000000000000000ull)) {
+		val <<= 2;
+		r -= 2;
+	}
+	if (!(val & 0x8000000000000000ull)) {
+		val <<= 1;
+		r -= 1;
+	}
+	return r;
+#if HAVE_BUILTIN_CLZL
+	}
+#endif
+}
+
+/* This is stolen straight from Hacker's Delight. */
+static uint64_t divlu64(uint64_t u1, uint64_t u0, uint64_t v)
+{
+	const uint64_t b = 4294967296ULL; // Number base (32 bits).
+	uint32_t un[4],		  // Dividend and divisor
+		vn[2];		  // normalized and broken
+				  // up into halfwords.
+	uint32_t q[2];		  // Quotient as halfwords.
+	uint64_t un1, un0,	  // Dividend and divisor
+		vn0;		  // as fullwords.
+	uint64_t qhat;		  // Estimated quotient digit.
+	uint64_t rhat;		  // A remainder.
+	uint64_t p;		  // Product of two digits.
+	int64_t s, i, j, t, k;
+
+	if (u1 >= v)		  // If overflow, return the largest
+		return (uint64_t)-1; // possible quotient.
+
+	s = 64 - fls64(v);		  // 0 <= s <= 63.
+	vn0 = v << s;		  // Normalize divisor.
+	vn[1] = vn0 >> 32;	  // Break divisor up into
+	vn[0] = vn0 & 0xFFFFFFFF; // two 32-bit halves.
+
+	// Shift dividend left.
+	un1 = ((u1 << s) | (u0 >> (64 - s))) & (-s >> 63);
+	un0 = u0 << s;
+	un[3] = un1 >> 32;	  // Break dividend up into
+	un[2] = un1;		  // four 32-bit halfwords
+	un[1] = un0 >> 32;	  // Note: storing into
+	un[0] = un0;		  // halfwords truncates.
+
+	for (j = 1; j >= 0; j--) {
+		// Compute estimate qhat of q[j].
+		qhat = (un[j+2]*b + un[j+1])/vn[1];
+		rhat = (un[j+2]*b + un[j+1]) - qhat*vn[1];
+	again:
+		if (qhat >= b || qhat*vn[0] > b*rhat + un[j]) {
+			qhat = qhat - 1;
+			rhat = rhat + vn[1];
+			if (rhat < b) goto again;
+		}
+
+		// Multiply and subtract.
+		k = 0;
+		for (i = 0; i < 2; i++) {
+			p = qhat*vn[i];
+			t = un[i+j] - k - (p & 0xFFFFFFFF);
+			un[i+j] = t;
+			k = (p >> 32) - (t >> 32);
+		}
+		t = un[j+2] - k;
+		un[j+2] = t;
+
+		q[j] = qhat;		  // Store quotient digit.
+		if (t < 0) {		  // If we subtracted too
+			q[j] = q[j] - 1;  // much, add back.
+			k = 0;
+			for (i = 0; i < 2; i++) {
+				t = un[i+j] + vn[i] + k;
+				un[i+j] = t;
+				k = t >> 32;
+			}
+			un[j+2] = un[j+2] + k;
+		}
+	} // End j.
+
+	return q[1]*b + q[0];
+}
+
+static int64_t divls64(int64_t u1, uint64_t u0, int64_t v)
+{
+	int64_t q, uneg, vneg, diff, borrow;
+
+	uneg = u1 >> 63;	  // -1 if u < 0.
+	if (uneg) {		  // Compute the absolute
+		u0 = -u0;	  // value of the dividend u.
+		borrow = (u0 != 0);
+		u1 = -u1 - borrow;
+	}
+
+	vneg = v >> 63;		  // -1 if v < 0.
+	v = (v ^ vneg) - vneg;	  // Absolute value of v.
+
+	if ((uint64_t)u1 >= (uint64_t)v)
+		goto overflow;
+
+	q = divlu64(u1, u0, v);
+
+	diff = uneg ^ vneg;	  // Negate q if signs of
+	q = (q ^ diff) - diff;	  // u and v differed.
+
+	if ((diff ^ q) < 0 && q != 0) {	   // If overflow, return the largest
+	overflow:			   // possible neg. quotient.
+		q = 0x8000000000000000ULL;
+	}
+	return q;
+}
+
+ssize_t tally_mean(const struct tally *tally)
+{
+	size_t count = tally_num(tally);
+	if (!count)
+		return 0;
+
+	if (sizeof(tally->total[0]) == sizeof(uint32_t)) {
+		/* Use standard 64-bit arithmetic. */
+		int64_t total = tally->total[0]
+			| (((uint64_t)tally->total[1]) << 32);
+		return total / count;
+	}
+	return divls64(tally->total[1], tally->total[0], count);
+}
+
+ssize_t tally_total(const struct tally *tally, ssize_t *overflow)
+{
+	if (overflow) {
+		*overflow = tally->total[1];
+		return tally->total[0];
+	}
+
+	/* If result is negative, make sure we can represent it. */
+	if (tally->total[1] & ((size_t)1 << (SIZET_BITS-1))) {
+		/* Must have only underflowed once, and must be able to
+		 * represent result at ssize_t. */
+		if ((~tally->total[1])+1 != 0
+		    || (ssize_t)tally->total[0] >= 0) {
+			/* Underflow, return minimum. */
+			return (ssize_t)((size_t)1 << (SIZET_BITS - 1));
+		}
+	} else {
+		/* Result is positive, must not have overflowed, and must be
+		 * able to represent as ssize_t. */
+		if (tally->total[1] || (ssize_t)tally->total[0] < 0) {
+			/* Overflow.  Return maximum. */
+			return (ssize_t)~((size_t)1 << (SIZET_BITS - 1));
+		}
+	}
+	return tally->total[0];
+}
+
+static ssize_t bucket_range(const struct tally *tally, unsigned b, size_t *err)
+{
+	ssize_t min, max;
+
+	min = bucket_min(tally->min, tally->step_bits, b);
+	if (b == tally->buckets - 1)
+		max = tally->max;
+	else
+		max = bucket_min(tally->min, tally->step_bits, b+1) - 1;
+
+	/* FIXME: Think harder about cumulative error; is this enough?. */
+	*err = (max - min + 1) / 2;
+	/* Avoid overflow. */
+	return min + (max - min) / 2;
+}
+
+ssize_t tally_approx_median(const struct tally *tally, size_t *err)
+{
+	size_t count = tally_num(tally), total = 0;
+	unsigned int i;
+
+	for (i = 0; i < tally->buckets; i++) {
+		total += tally->counts[i];
+		if (total * 2 >= count)
+			break;
+	}
+	return bucket_range(tally, i, err);
+}
+
+ssize_t tally_approx_mode(const struct tally *tally, size_t *err)
+{
+	unsigned int i, min_best = 0, max_best = 0;
+
+	for (i = 0; i < tally->buckets; i++) {
+		if (tally->counts[i] > tally->counts[min_best]) {
+			min_best = max_best = i;
+		} else if (tally->counts[i] == tally->counts[min_best]) {
+			max_best = i;
+		}
+	}
+
+	/* We can have more than one best, making our error huge. */
+	if (min_best != max_best) {
+		ssize_t min, max;
+		min = bucket_range(tally, min_best, err);
+		max = bucket_range(tally, max_best, err);
+		max += *err;
+		*err += (size_t)(max - min);
+		return min + (max - min) / 2;
+	}
+
+	return bucket_range(tally, min_best, err);
+}
+
+static unsigned get_max_bucket(const struct tally *tally)
+{
+	unsigned int i;
+
+	for (i = tally->buckets; i > 0; i--)
+		if (tally->counts[i-1])
+			break;
+	return i;
+}
+
+char *tally_histogram(const struct tally *tally,
+		      unsigned width, unsigned height)
+{
+	unsigned int i, count, max_bucket, largest_bucket;
+	struct tally *tmp;
+	char *graph, *p;
+
+	assert(width >= TALLY_MIN_HISTO_WIDTH);
+	assert(height >= TALLY_MIN_HISTO_HEIGHT);
+
+	/* Ignore unused buckets. */
+	max_bucket = get_max_bucket(tally);
+
+	/* FIXME: It'd be nice to smooth here... */
+	if (height >= max_bucket) {
+		height = max_bucket;
+		tmp = NULL;
+	} else {
+		/* We create a temporary then renormalize so < height. */
+		/* FIXME: Antialias properly! */
+		tmp = tally_new(tally->buckets);
+		if (!tmp)
+			return NULL;
+		tmp->min = tally->min;
+		tmp->max = tally->max;
+		tmp->step_bits = tally->step_bits;
+		memcpy(tmp->counts, tally->counts,
+		       sizeof(tally->counts[0]) * tmp->buckets);
+		while ((max_bucket = get_max_bucket(tmp)) >= height)
+			renormalize(tmp, tmp->min, tmp->max * 2);
+		/* Restore max */
+		tmp->max = tally->max;
+		tally = tmp;
+		height = max_bucket;
+	}
+
+	/* Figure out longest line, for scale. */
+	largest_bucket = 0;
+	for (i = 0; i < tally->buckets; i++) {
+		if (tally->counts[i] > largest_bucket)
+			largest_bucket = tally->counts[i];
+	}
+
+	p = graph = malloc(height * (width + 1) + 1);
+	if (!graph) {
+		free(tmp);
+		return NULL;
+	}
+
+	for (i = 0; i < height; i++) {
+		unsigned covered = 1, row;
+
+		/* People expect minimum at the bottom. */
+		row = height - i - 1;
+		count = (double)tally->counts[row] / largest_bucket * (width-1)+1;
+
+		if (row == 0)
+			covered = snprintf(p, width, "%zi", tally->min);
+		else if (row == height - 1)
+			covered = snprintf(p, width, "%zi", tally->max);
+		else if (row == bucket_of(tally->min, tally->step_bits, 0))
+			*p = '+';
+		else
+			*p = '|';
+
+		if (covered > width)
+			covered = width;
+		p += covered;
+
+		if (count > covered)
+			count -= covered;
+		else
+			count = 0;
+
+		memset(p, '*', count);
+		p += count;
+		*p = '\n';
+		p++;
+	}
+	*p = '\0';
+	free(tmp);
+	return graph;
+}
diff --git a/lib/ccan/tally/tally.h b/lib/ccan/tally/tally.h
new file mode 100644
index 0000000000..e715717507
--- /dev/null
+++ b/lib/ccan/tally/tally.h
@@ -0,0 +1,103 @@
+#ifndef CCAN_TALLY_H
+#define CCAN_TALLY_H
+#include <stdlib.h>
+
+struct tally;
+
+/**
+ * tally_new - allocate the tally structure.
+ * @buckets: the number of frequency buckets.
+ *
+ * This allocates a tally structure using malloc().  The greater the value
+ * of @buckets, the more accurate tally_approx_median() and tally_approx_mode()
+ * and tally_histogram() will be, but more memory is consumed.  If you want
+ * to use tally_histogram(), the optimal bucket value is the same as that
+ * @height argument.
+ */
+struct tally *tally_new(unsigned int buckets);
+
+/**
+ * tally_add - add a value.
+ * @tally: the tally structure.
+ * @val: the value to add.
+ */
+void tally_add(struct tally *tally, ssize_t val);
+
+/**
+ * tally_num - how many times as tally_add been called?
+ * @tally: the tally structure.
+ */
+size_t tally_num(const struct tally *tally);
+
+/**
+ * tally_min - the minimum value passed to tally_add.
+ * @tally: the tally structure.
+ *
+ * Undefined if tally_num() == 0.
+ */
+ssize_t tally_min(const struct tally *tally);
+
+/**
+ * tally_max - the maximum value passed to tally_add.
+ * @tally: the tally structure.
+ *
+ * Undefined if tally_num() == 0.
+ */
+ssize_t tally_max(const struct tally *tally);
+
+/**
+ * tally_mean - the mean value passed to tally_add.
+ * @tally: the tally structure.
+ *
+ * Undefined if tally_num() == 0, but will not crash.
+ */
+ssize_t tally_mean(const struct tally *tally);
+
+/**
+ * tally_total - the total value passed to tally_add.
+ * @tally: the tally structure.
+ * @overflow: the overflow value (or NULL).
+ *
+ * If your total can't overflow a ssize_t, you don't need @overflow.
+ * Otherwise, @overflow is the upper ssize_t, and the return value should
+ * be treated as the lower size_t (ie. the sign bit is in @overflow).
+ */
+ssize_t tally_total(const struct tally *tally, ssize_t *overflow);
+
+/**
+ * tally_approx_median - the approximate median value passed to tally_add.
+ * @tally: the tally structure.
+ * @err: the error in the returned value (ie. real median is +/- @err).
+ *
+ * Undefined if tally_num() == 0, but will not crash.  Because we
+ * don't reallocate, we don't store all values, so this median cannot be
+ * exact.
+ */
+ssize_t tally_approx_median(const struct tally *tally, size_t *err);
+
+/**
+ * tally_approx_mode - the approximate mode value passed to tally_add.
+ * @tally: the tally structure.
+ * @err: the error in the returned value (ie. real mode is +/- @err).
+ *
+ * Undefined if tally_num() == 0, but will not crash.  Because we
+ * don't reallocate, we don't store all values, so this mode cannot be
+ * exact.  It could well be a value which was never passed to tally_add!
+ */
+ssize_t tally_approx_mode(const struct tally *tally, size_t *err);
+
+#define TALLY_MIN_HISTO_WIDTH 8
+#define TALLY_MIN_HISTO_HEIGHT 3
+
+/**
+ * tally_graph - return an ASCII image of the tally_add distribution
+ * @tally: the tally structure.
+ * @width: the maximum string width to use (>= TALLY_MIN_HISTO_WIDTH)
+ * @height: the maximum string height to use (>= TALLY_MIN_HISTO_HEIGHT)
+ *
+ * Returns a malloc()ed string which draws a multi-line graph of the
+ * distribution of values.  On out of memory returns NULL.
+ */
+char *tally_histogram(const struct tally *tally,
+		      unsigned width, unsigned height);
+#endif /* CCAN_TALLY_H */
diff --git a/lib/ccan/tally/test/run-bucket_of.c b/lib/ccan/tally/test/run-bucket_of.c
new file mode 100644
index 0000000000..5e12725757
--- /dev/null
+++ b/lib/ccan/tally/test/run-bucket_of.c
@@ -0,0 +1,71 @@
+#include <ccan/tally/tally.c>
+#include <ccan/tap/tap.h>
+
+int main(void)
+{
+	unsigned int i, max_step;
+	ssize_t min, max;
+
+	max = (ssize_t)~(1ULL << (sizeof(max)*CHAR_BIT - 1));
+	min = (ssize_t)(1ULL << (sizeof(max)*CHAR_BIT - 1));
+	max_step = sizeof(max)*CHAR_BIT;
+
+	plan_tests(2 + 100 + 10 + 5
+		   + 2 + 100 + 5 + 4
+		   + (1 << 7) * (max_step - 7));
+
+	/* Single step, single bucket == easy. */
+	ok1(bucket_of(0, 0, 0) == 0);
+
+	/* Double step, still in first bucket. */
+	ok1(bucket_of(0, 1, 0) == 0);
+
+	/* Step 8. */
+	for (i = 0; i < 100; i++)
+		ok1(bucket_of(0, 3, i) == i >> 3);
+
+	/* 10 values in 5 buckets, step 2. */
+	for (i = 0; i < 10; i++)
+		ok1(bucket_of(0, 1, i) == i >> 1);
+
+	/* Extreme cases. */
+	ok1(bucket_of(min, 0, min) == 0);
+	ok1(bucket_of(min, max_step-1, min) == 0);
+	ok1(bucket_of(min, max_step-1, max) == 1);
+	ok1(bucket_of(min, max_step, min) == 0);
+	ok1(bucket_of(min, max_step, max) == 0);
+
+	/* Now, bucket_min() should match: */
+	ok1(bucket_min(0, 0, 0) == 0);
+
+	/* Double step, val in first bucket still 0. */
+	ok1(bucket_min(0, 1, 0) == 0);
+
+	/* Step 8. */
+	for (i = 0; i < 100; i++)
+		ok1(bucket_min(0, 3, i) == i << 3);
+
+	/* 10 values in 5 buckets, step 2. */
+	for (i = 0; i < 5; i++)
+		ok1(bucket_min(0, 1, i) == i << 1);
+
+	/* Extreme cases. */
+	ok1(bucket_min(min, 0, 0) == min);
+	ok1(bucket_min(min, max_step-1, 0) == min);
+	ok1(bucket_min(min, max_step-1, 1) == 0);
+	ok1(bucket_min(min, max_step, 0) == min);
+
+	/* Now, vary step and number of buckets, but bucket_min and bucket_of
+	 * must agree. */
+	for (i = 0; i < (1 << 7); i++) {
+		unsigned int j;
+		for (j = 0; j < max_step - 7; j++) {
+			ssize_t val;
+
+			val = bucket_min(-(ssize_t)i, j, i);
+			ok1(bucket_of(-(ssize_t)i, j, val) == i);
+		}
+	}
+
+	return exit_status();
+}
diff --git a/lib/ccan/tally/test/run-divlu64.c b/lib/ccan/tally/test/run-divlu64.c
new file mode 100644
index 0000000000..057e47432c
--- /dev/null
+++ b/lib/ccan/tally/test/run-divlu64.c
@@ -0,0 +1,31 @@
+#include <ccan/tally/tally.c>
+#include <ccan/tap/tap.h>
+
+int main(void)
+{
+	unsigned int i, j;
+
+	plan_tests(5985);
+	/* Simple tests. */
+	for (i = 0; i < 127; i++) {
+		uint64_t u1, u0;
+		if (i < 64) {
+			u1 = 0;
+			u0 = 1ULL << i;
+			j = 0;
+		} else {
+			u1 = 1ULL << (i - 64);
+			u0 = 0;
+			j = i - 63;
+		}
+		for (; j < 63; j++) {
+			uint64_t answer;
+			if (j > i)
+				answer = 0;
+			else
+				answer = 1ULL << (i - j);
+			ok1(divlu64(u1, u0, 1ULL << j) == answer);
+		}
+	}
+	return exit_status();
+}
diff --git a/lib/ccan/tally/test/run-histogram.c b/lib/ccan/tally/test/run-histogram.c
new file mode 100644
index 0000000000..a9894ecd85
--- /dev/null
+++ b/lib/ccan/tally/test/run-histogram.c
@@ -0,0 +1,108 @@
+#include <ccan/tally/tally.c>
+#include <ccan/tap/tap.h>
+
+int main(void)
+{
+	int i;
+	struct tally *tally;
+	char *graph, *p;
+
+	plan_tests(100 + 1 + 10 + 1 + 100 + 1 + 10 + 1 + 10 * 2 + 1);
+
+	/* Uniform distribution, easy. */
+	tally = tally_new(100);
+	for (i = 0; i < 100; i++)
+		tally_add(tally, i);
+
+	/* 1:1 height. */
+	graph = p = tally_histogram(tally, 20, 100);
+	for (i = 0; i < 100; i++) {
+		char *eol = strchr(p, '\n');
+
+		/* We expect it filled all way to the end. */
+		ok1(eol - p == 20);
+		p = eol + 1;
+	}
+	ok1(!*p);
+	free(graph);
+
+	/* Reduced height. */
+	graph = p = tally_histogram(tally, 20, 10);
+	for (i = 0; i < 10; i++) {
+		char *eol = strchr(p, '\n');
+
+		/* First once can be truncated (bucket aliasing) */
+		if (eol) {
+			ok1(eol - p == 20 || (eol - p < 20 && i == 0));
+		} else
+			/* We should, at worst, half-fill graph */
+			ok1(i > 5);
+
+		if (eol)
+			p = eol + 1;
+	}
+	ok1(!*p);
+	free(graph);
+
+	/* Enlarged height (gets capped). */
+	graph = p = tally_histogram(tally, 20, 1000);
+	for (i = 0; i < 100; i++) {
+		char *eol = strchr(p, '\n');
+		/* We expect it filled all way to the end. */
+		ok1(eol - p == 20);
+		p = eol + 1;
+	}
+	ok1(!*p);
+	free(graph);
+	free(tally);
+
+	/* Distinctive increasing pattern. */
+	tally = tally_new(10);
+	for (i = 0; i < 10; i++) {
+		unsigned int j;
+		for (j = 0; j <= i; j++)
+			tally_add(tally, i);
+	}
+
+	graph = p = tally_histogram(tally, 10, 10);
+	for (i = 0; i < 10; i++) {
+		char *eol = strchr(p, '\n');
+		ok1(eol - p == 10 - i);
+		p = eol + 1;
+	}
+	ok1(!*p);
+	diag("Here's the pretty: %s", graph);
+	free(graph);
+	free(tally);
+
+	/* With negative values. */
+	tally = tally_new(10);
+	for (i = 0; i < 10; i++) {
+		tally_add(tally, i - 5);
+	}
+
+	graph = p = tally_histogram(tally, 10, 10);
+	for (i = 0; i < 10; i++) {
+		char *eol = strchr(p, '\n');
+
+		/* We expect it filled all way to the end. */
+		ok1(eol - p == 10);
+
+		/* Check min/max labels. */
+		if (i == 0)
+			ok1(strncmp(p, "4*", 2) == 0);
+		else if (i == 9)
+			ok1(strncmp(p, "-5*", 3) == 0);
+		else if (i == 4)
+			ok1(p[0] == '+'); /* 0 marker */
+		else
+			ok1(p[0] == '|');
+		p = eol + 1;
+	}
+	ok1(!*p);
+	diag("Here's the pretty: %s", graph);
+	free(graph);
+	free(tally);
+
+	return exit_status();
+}
diff --git a/lib/ccan/tally/test/run-mean.c b/lib/ccan/tally/test/run-mean.c
new file mode 100644
index 0000000000..a4a67cf9c8
--- /dev/null
+++ b/lib/ccan/tally/test/run-mean.c
@@ -0,0 +1,29 @@
+#include <ccan/tally/tally.c>
+#include <ccan/tap/tap.h>
+
+int main(void)
+{
+	int i;
+	struct tally *tally = tally_new(0);
+	ssize_t min, max;
+
+	max = (ssize_t)~(1ULL << (sizeof(max)*CHAR_BIT - 1));
+	min = (ssize_t)(1ULL << (sizeof(max)*CHAR_BIT - 1));
+
+	plan_tests(100 + 100);
+	/* Simple mean test: should always be 0. */
+	for (i = 0; i < 100; i++) {
+		tally_add(tally, i);
+		tally_add(tally, -i);
+		ok1(tally_mean(tally) == 0);
+	}
+
+	/* Works for big values too... */
+	for (i = 0; i < 100; i++) {
+		tally_add(tally, max - i);
+		tally_add(tally, min + 1 + i);
+		ok1(tally_mean(tally) == 0);
+	}
+
+	return exit_status();
+}
diff --git a/lib/ccan/tally/test/run-median.c b/lib/ccan/tally/test/run-median.c
new file mode 100644
index 0000000000..f461c2ec8f
--- /dev/null
+++ b/lib/ccan/tally/test/run-median.c
@@ -0,0 +1,45 @@
+#include <ccan/tally/tally.c>
+#include <ccan/tap/tap.h>
+
+int main(void)
+{
+	int i;
+	struct tally *tally = tally_new(100);
+	ssize_t min, max, median;
+	size_t err;
+
+	max = (ssize_t)~(1ULL << (sizeof(max)*CHAR_BIT - 1));
+	min = (ssize_t)(1ULL << (sizeof(max)*CHAR_BIT - 1));
+
+	plan_tests(100*2 + 100*2 + 100*2);
+	/* Simple median test: should always be around 0. */
+	for (i = 0; i < 100; i++) {
+		tally_add(tally, i);
+		tally_add(tally, -i);
+		median = tally_approx_median(tally, &err);
+		ok1(err <= 4);
+		ok1(median - (ssize_t)err <= 0 && median + (ssize_t)err >= 0);
+	}
+
+	/* Works for big values too... */
+	for (i = 0; i < 100; i++) {
+		tally_add(tally, max - i);
+		tally_add(tally, min + 1 + i);
+		median = tally_approx_median(tally, &err);
+		/* Error should be < 100th of max - min. */
+		ok1(err <= max / 100 * 2);
+		ok1(median - (ssize_t)err <= 0 && median + (ssize_t)err >= 0);
+	}
+	free(tally);
+
+	tally = tally_new(10);
+	for (i = 0; i < 100; i++) {
+		tally_add(tally, i);
+		median = tally_approx_median(tally, &err);
+		ok1(err <= i / 10 + 1);
+		ok1(median - (ssize_t)err <= i/2
+		    && median + (ssize_t)err >= i/2);
+	}
+
+	return exit_status();
+}
diff --git a/lib/ccan/tally/test/run-min-max.c b/lib/ccan/tally/test/run-min-max.c
new file mode 100644
index 0000000000..ffb0f2eff4
--- /dev/null
+++ b/lib/ccan/tally/test/run-min-max.c
@@ -0,0 +1,20 @@
+#include <ccan/tally/tally.c>
+#include <ccan/tap/tap.h>
+
+int main(void)
+{
+	int i;
+	struct tally *tally = tally_new(0);
+
+	plan_tests(100 * 4);
+	/* Test max, min and num. */
+	for (i = 0; i < 100; i++) {
+		tally_add(tally, i);
+		ok1(tally_num(tally) == i*2 + 1);
+		tally_add(tally, -i);
+		ok1(tally_num(tally) == i*2 + 2);
+		ok1(tally_max(tally) == i);
+		ok1(tally_min(tally) == -i);
+	}
+	return exit_status();
+}
diff --git a/lib/ccan/tally/test/run-mode.c b/lib/ccan/tally/test/run-mode.c
new file mode 100644
index 0000000000..7216738bfb
--- /dev/null
+++ b/lib/ccan/tally/test/run-mode.c
@@ -0,0 +1,45 @@
+#include <ccan/tally/tally.c>
+#include <ccan/tap/tap.h>
+
+int main(void)
+{
+	int i;
+	struct tally *tally = tally_new(100);
+	ssize_t min, max, mode;
+	size_t err;
+
+	max = (ssize_t)~(1ULL << (sizeof(max)*CHAR_BIT - 1));
+	min = (ssize_t)(1ULL << (sizeof(max)*CHAR_BIT - 1));
+
+	plan_tests(100 + 50 + 100 + 100 + 10);
+	/* Simple mode test: should always be around 0 (we add that twice). */
+	for (i = 0; i < 100; i++) {
+		tally_add(tally, i);
+		tally_add(tally, -i);
+		mode = tally_approx_mode(tally, &err);
+		if (i < 50)
+			ok1(err == 0);
+		ok1(mode - (ssize_t)err <= 0 && mode + (ssize_t)err >= 0);
+	}
+
+	/* Works for big values too... */
+	for (i = 0; i < 100; i++) {
+		tally_add(tally, max - i);
+		tally_add(tally, min + 1 + i);
+		mode = tally_approx_mode(tally, &err);
+		ok1(mode - (ssize_t)err <= 0 && mode + (ssize_t)err >= 0);
+	}
+	free(tally);
+
+	tally = tally_new(10);
+	tally_add(tally, 0);
+	for (i = 0; i < 100; i++) {
+		tally_add(tally, i);
+		mode = tally_approx_mode(tally, &err);
+		if (i < 10)
+			ok1(err == 0);
+		ok1(mode - (ssize_t)err <= 0 && mode + (ssize_t)err >= 0);
+	}
+
+	return exit_status();
+}
diff --git a/lib/ccan/tally/test/run-renormalize.c b/lib/ccan/tally/test/run-renormalize.c
new file mode 100644
index 0000000000..7c141528d2
--- /dev/null
+++ b/lib/ccan/tally/test/run-renormalize.c
@@ -0,0 +1,25 @@
+#include <ccan/tally/tally.c>
+#include <ccan/tap/tap.h>
+
+int main(void)
+{
+	struct tally *tally = tally_new(2);
+
+	plan_tests(4);
+	tally->min = 0;
+	tally->max = 0;
+	tally->counts[0] = 1;
+
+	/* This renormalize should do nothing. */
+	renormalize(tally, 0, 1);
+	ok1(tally->counts[0] == 1);
+	ok1(tally->counts[1] == 0);
+	tally->counts[1]++;
+
+	/* This renormalize should collapse both into bucket 0. */
+	renormalize(tally, 0, 3);
+	ok1(tally->counts[0] == 2);
+	ok1(tally->counts[1] == 0);
+
+	return exit_status();
+}
diff --git a/lib/ccan/tally/test/run-total.c b/lib/ccan/tally/test/run-total.c
new file mode 100644
index 0000000000..d7d73e58a5
--- /dev/null
+++ b/lib/ccan/tally/test/run-total.c
@@ -0,0 +1,56 @@
+#include <ccan/tally/tally.c>
+#include <ccan/tap/tap.h>
+
+int main(void)
+{
+	struct tally *tally;
+	ssize_t total, overflow;
+	ssize_t min, max;
+
+	max = (ssize_t)~(1ULL << (sizeof(max)*CHAR_BIT - 1));
+	min = (ssize_t)(1ULL << (sizeof(max)*CHAR_BIT - 1));
+
+	plan_tests(15);
+
+	/* Simple case. */
+	tally = tally_new(0);
+	tally_add(tally, min);
+	ok1(tally_total(tally, NULL) == min);
+	ok1(tally_total(tally, &overflow) == min);
+	ok1(overflow == -1);
+
+	/* Underflow. */
+	tally_add(tally, min);
+	total = tally_total(tally, &overflow);
+	ok1(overflow == -1);
+	ok1((size_t)total == 0);
+	ok1(tally_total(tally, NULL) == min);
+	free(tally);
+
+	/* Simple case. */
+	tally = tally_new(0);
+	tally_add(tally, max);
+	ok1(tally_total(tally, NULL) == max);
+	ok1(tally_total(tally, &overflow) == max);
+	ok1(overflow == 0);
+
+	/* Overflow into sign bit... */
+	tally_add(tally, max);
+	total = tally_total(tally, &overflow);
+	ok1(overflow == 0);
+	ok1((size_t)total == (size_t)-2);
+	ok1(tally_total(tally, NULL) == max);
+
+	/* Overflow into upper size_t. */
+	tally_add(tally, max);
+	total = tally_total(tally, &overflow);
+	ok1(overflow == 1);
+	if (sizeof(size_t) == 4)
+		ok1((size_t)total == 0x7FFFFFFD);
+	else if (sizeof(size_t) == 8)
+		ok1((size_t)total == 0x7FFFFFFFFFFFFFFDULL);
+	ok1(tally_total(tally, NULL) == max);
+	free(tally);
+
+	return exit_status();
+}
diff --git a/lib/ccan/typesafe_cb/LICENSE b/lib/ccan/typesafe_cb/LICENSE
new file mode 100644
index 0000000000..5522aa5f33
--- /dev/null
+++ b/lib/ccan/typesafe_cb/LICENSE
@@ -0,0 +1,508 @@
+
+                  GNU LESSER GENERAL PUBLIC LICENSE
+                       Version 2.1, February 1999
+
+ Copyright (C) 1991, 1999 Free Software Foundation, Inc.
+	51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
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diff --git a/lib/ccan/typesafe_cb/_info b/lib/ccan/typesafe_cb/_info
new file mode 100644
index 0000000000..4f4570afc9
--- /dev/null
+++ b/lib/ccan/typesafe_cb/_info
@@ -0,0 +1,151 @@
+#include <stdio.h>
+#include <string.h>
+#include "config.h"
+
+/**
+ * typesafe_cb - macros for safe callbacks.
+ *
+ * The basis of the typesafe_cb header is typesafe_cb_cast(): a
+ * conditional cast macro.   If an expression exactly matches a given
+ * type, it is cast to the target type, otherwise it is left alone.
+ *
+ * This allows us to create functions which take a small number of
+ * specific types, rather than being forced to use a void *.  In
+ * particular, it is useful for creating typesafe callbacks as the
+ * helpers typesafe_cb(), typesafe_cb_preargs() and
+ * typesafe_cb_postargs() demonstrate.
+ *
+ * The standard way of passing arguments to callback functions in C is
+ * to use a void pointer, which the callback then casts back to the
+ * expected type.  This unfortunately subverts the type checking the
+ * compiler would perform if it were a direct call.  Here's an example:
+ *
+ *	static void my_callback(void *_obj)
+ *	{
+ *		struct obj *obj = _obj;
+ *		...
+ *	}
+ *	...
+ *		register_callback(my_callback, &my_obj);
+ *
+ * If we wanted to use the natural type for my_callback (ie. "void
+ * my_callback(struct obj *obj)"), we could make register_callback()
+ * take a void * as its first argument, but this would subvert all
+ * type checking.  We really want register_callback() to accept only
+ * the exactly correct function type to match the argument, or a
+ * function which takes a void *.
+ *
+ * This is where typesafe_cb() comes in: it uses typesafe_cb_cast() to
+ * cast the callback function if it matches the argument type:
+ *
+ *	void _register_callback(void (*cb)(void *arg), void *arg);
+ *	#define register_callback(cb, arg)				\
+ *		_register_callback(typesafe_cb(void, void *, (cb), (arg)), \
+ *				   (arg))
+ *
+ * On compilers which don't support the extensions required
+ * typesafe_cb_cast() and friend become an unconditional cast, so your
+ * code will compile but you won't get type checking.
+ *
+ * Example:
+ *	#include <ccan/typesafe_cb/typesafe_cb.h>
+ *	#include <stdlib.h>
+ *	#include <stdio.h>
+ *
+ *	// Generic callback infrastructure.
+ *	struct callback {
+ *		struct callback *next;
+ *		int value;
+ *		int (*callback)(int value, void *arg);
+ *		void *arg;
+ *	};
+ *	static struct callback *callbacks;
+ *
+ *	static void _register_callback(int value, int (*cb)(int, void *),
+ *				       void *arg)
+ *	{
+ *		struct callback *new = malloc(sizeof(*new));
+ *		new->next = callbacks;
+ *		new->value = value;
+ *		new->callback = cb;
+ *		new->arg = arg;
+ *		callbacks = new;
+ *	}
+ *	#define register_callback(value, cb, arg)			\
+ *		_register_callback(value,				\
+ *				   typesafe_cb_preargs(int, void *,	\
+ *						       (cb), (arg), int),\
+ *				   (arg))
+ *
+ *	static struct callback *find_callback(int value)
+ *	{
+ *		struct callback *i;
+ *
+ *		for (i = callbacks; i; i = i->next)
+ *			if (i->value == value)
+ *				return i;
+ *		return NULL;
+ *	}
+ *
+ *	// Define several silly callbacks.  Note they don't use void *!
+ *	#define DEF_CALLBACK(name, op)			\
+ *		static int name(int val, int *arg)	\
+ *		{					\
+ *			printf("%s", #op);		\
+ *			return val op *arg;		\
+ *		}
+ *	DEF_CALLBACK(multiply, *);
+ *	DEF_CALLBACK(add, +);
+ *	DEF_CALLBACK(divide, /);
+ *	DEF_CALLBACK(sub, -);
+ *	DEF_CALLBACK(or, |);
+ *	DEF_CALLBACK(and, &);
+ *	DEF_CALLBACK(xor, ^);
+ *	DEF_CALLBACK(assign, =);
+ *
+ *	// Silly game to find the longest chain of values.
+ *	int main(int argc, char *argv[])
+ *	{
+ *		int i, run = 1, num = argv[1] ? atoi(argv[1]) : 0;
+ *
+ *		for (i = 1; i < 1024;) {
+ *			// Since run is an int, compiler checks "add" does too.
+ *			register_callback(i++, add, &run);
+ *			register_callback(i++, divide, &run);
+ *			register_callback(i++, sub, &run);
+ *			register_callback(i++, multiply, &run);
+ *			register_callback(i++, or, &run);
+ *			register_callback(i++, and, &run);
+ *			register_callback(i++, xor, &run);
+ *			register_callback(i++, assign, &run);
+ *		}
+ *
+ *		printf("%i ", num);
+ *		while (run < 56) {
+ *			struct callback *cb = find_callback(num % i);
+ *			if (!cb) {
+ *				printf("-> STOP\n");
+ *				return 1;
+ *			}
+ *			num = cb->callback(num, cb->arg);
+ *			printf("->%i ", num);
+ *			run++;
+ *		}
+ *		printf("-> Winner!\n");
+ *		return 0;
+ *	}
+ *
+ * License: LGPL (2 or any later version)
+ * Author: Rusty Russell <rusty@rustcorp.com.au>
+ */
+int main(int argc, char *argv[])
+{
+	if (argc != 2)
+		return 1;
+
+	if (strcmp(argv[1], "depends") == 0) {
+		return 0;
+	}
+
+	return 1;
+}
diff --git a/lib/ccan/typesafe_cb/test/compile_fail-cast_if_any.c b/lib/ccan/typesafe_cb/test/compile_fail-cast_if_any.c
new file mode 100644
index 0000000000..dfb51167ff
--- /dev/null
+++ b/lib/ccan/typesafe_cb/test/compile_fail-cast_if_any.c
@@ -0,0 +1,42 @@
+#include <ccan/typesafe_cb/typesafe_cb.h>
+#include <stdlib.h>
+
+struct foo {
+	int x;
+};
+
+struct bar {
+	int x;
+};
+
+struct baz {
+	int x;
+};
+
+struct any {
+	int x;
+};
+
+struct other {
+	int x;
+};
+
+static void take_any(struct any *any)
+{
+}
+
+int main(int argc, char *argv[])
+{
+#ifdef FAIL
+	struct other
+#if !HAVE_TYPEOF||!HAVE_BUILTIN_CHOOSE_EXPR||!HAVE_BUILTIN_TYPES_COMPATIBLE_P
+#error "Unfortunately we don't fail if cast_if_type is a noop."
+#endif
+#else
+	struct foo
+#endif
+		*arg = NULL;
+	take_any(cast_if_any(struct any *, arg, arg,
+			     struct foo *, struct bar *, struct baz *));
+	return 0;
+}
diff --git a/lib/ccan/typesafe_cb/test/compile_fail-cast_if_type-promotable.c b/lib/ccan/typesafe_cb/test/compile_fail-cast_if_type-promotable.c
new file mode 100644
index 0000000000..11d42f4c6b
--- /dev/null
+++ b/lib/ccan/typesafe_cb/test/compile_fail-cast_if_type-promotable.c
@@ -0,0 +1,23 @@
+#include <ccan/typesafe_cb/typesafe_cb.h>
+#include <stdbool.h>
+
+static void _set_some_value(void *val)
+{
+}
+
+#define set_some_value(expr)						\
+	_set_some_value(typesafe_cb_cast(void *, long, (expr)))
+
+int main(int argc, char *argv[])
+{
+#ifdef FAIL
+	bool x = 0;
+#if !HAVE_TYPEOF||!HAVE_BUILTIN_CHOOSE_EXPR||!HAVE_BUILTIN_TYPES_COMPATIBLE_P
+#error "Unfortunately we don't fail if typesafe_cb_cast is a noop."
+#endif
+#else
+	long x = 0;
+#endif
+	set_some_value(x);
+	return 0;
+}
diff --git a/lib/ccan/typesafe_cb/test/compile_fail-cast_if_type.c b/lib/ccan/typesafe_cb/test/compile_fail-cast_if_type.c
new file mode 100644
index 0000000000..610793514f
--- /dev/null
+++ b/lib/ccan/typesafe_cb/test/compile_fail-cast_if_type.c
@@ -0,0 +1,25 @@
+#include <ccan/typesafe_cb/typesafe_cb.h>
+
+void _set_some_value(void *val);
+
+void _set_some_value(void *val)
+{
+}
+
+#define set_some_value(expr)						\
+	_set_some_value(cast_if_type(void *, (expr), (expr), unsigned long))
+
+int main(int argc, char *argv[])
+{
+#ifdef FAIL
+	int x = 0;
+	set_some_value(x);
+#if !HAVE_TYPEOF||!HAVE_BUILTIN_CHOOSE_EXPR||!HAVE_BUILTIN_TYPES_COMPATIBLE_P
+#error "Unfortunately we don't fail if cast_if_type is a noop."
+#endif
+#else
+	void *p = 0;
+	set_some_value(p);
+#endif
+	return 0;
+}
diff --git a/lib/ccan/typesafe_cb/test/compile_fail-typesafe_cb-int.c b/lib/ccan/typesafe_cb/test/compile_fail-typesafe_cb-int.c
new file mode 100644
index 0000000000..c4033364d4
--- /dev/null
+++ b/lib/ccan/typesafe_cb/test/compile_fail-typesafe_cb-int.c
@@ -0,0 +1,27 @@
+#include <ccan/typesafe_cb/typesafe_cb.h>
+#include <stdlib.h>
+
+void _callback(void (*fn)(void *arg), void *arg);
+void _callback(void (*fn)(void *arg), void *arg)
+{
+	fn(arg);
+}
+
+/* Callback is set up to warn if arg isn't a pointer (since it won't
+ * pass cleanly to _callback's second arg. */
+#define callback(fn, arg)						\
+	_callback(typesafe_cb(void, (fn), (arg)), (arg))
+
+void my_callback(int something);
+void my_callback(int something)
+{
+}
+
+int main(int argc, char *argv[])
+{
+#ifdef FAIL
+	/* This fails due to arg, not due to cast. */
+	callback(my_callback, 100);
+#endif
+	return 0;
+}
diff --git a/lib/ccan/typesafe_cb/test/compile_fail-typesafe_cb.c b/lib/ccan/typesafe_cb/test/compile_fail-typesafe_cb.c
new file mode 100644
index 0000000000..81e36d7b87
--- /dev/null
+++ b/lib/ccan/typesafe_cb/test/compile_fail-typesafe_cb.c
@@ -0,0 +1,34 @@
+#include <ccan/typesafe_cb/typesafe_cb.h>
+#include <stdlib.h>
+
+static void _register_callback(void (*cb)(void *arg), void *arg)
+{
+}
+
+#define register_callback(cb, arg)				\
+	_register_callback(typesafe_cb(void, void *, (cb), (arg)), (arg))
+
+static void my_callback(char *p)
+{
+}
+
+int main(int argc, char *argv[])
+{
+	char str[] = "hello world";
+#ifdef FAIL
+	int *p;
+#if !HAVE_TYPEOF||!HAVE_BUILTIN_CHOOSE_EXPR||!HAVE_BUILTIN_TYPES_COMPATIBLE_P
+#error "Unfortunately we don't fail if typesafe_cb_cast is a noop."
+#endif
+#else
+	char *p;
+#endif
+	p = NULL;
+
+	/* This should work always. */
+	register_callback(my_callback, str);
+
+	/* This will fail with FAIL defined */
+	register_callback(my_callback, p);
+	return 0;
+}
diff --git a/lib/ccan/typesafe_cb/test/compile_fail-typesafe_cb_cast-multi.c b/lib/ccan/typesafe_cb/test/compile_fail-typesafe_cb_cast-multi.c
new file mode 100644
index 0000000000..62b5f91e18
--- /dev/null
+++ b/lib/ccan/typesafe_cb/test/compile_fail-typesafe_cb_cast-multi.c
@@ -0,0 +1,43 @@
+#include <ccan/typesafe_cb/typesafe_cb.h>
+#include <stdlib.h>
+
+struct foo {
+	int x;
+};
+
+struct bar {
+	int x;
+};
+
+struct baz {
+	int x;
+};
+
+struct any {
+	int x;
+};
+
+struct other {
+	int x;
+};
+
+static void take_any(struct any *any)
+{
+}
+
+int main(int argc, char *argv[])
+{
+#ifdef FAIL
+	struct other
+#if !HAVE_TYPEOF||!HAVE_BUILTIN_CHOOSE_EXPR||!HAVE_BUILTIN_TYPES_COMPATIBLE_P
+#error "Unfortunately we don't fail if typesafe_cb_cast is a noop."
+#endif
+#else
+	struct foo
+#endif
+		*arg = NULL;
+	take_any(typesafe_cb_cast3(struct any *,
+				   struct foo *, struct bar *, struct baz *,
+				   arg));
+	return 0;
+}
diff --git a/lib/ccan/typesafe_cb/test/compile_fail-typesafe_cb_cast.c b/lib/ccan/typesafe_cb/test/compile_fail-typesafe_cb_cast.c
new file mode 100644
index 0000000000..d2e6f2ab40
--- /dev/null
+++ b/lib/ccan/typesafe_cb/test/compile_fail-typesafe_cb_cast.c
@@ -0,0 +1,25 @@
+#include <ccan/typesafe_cb/typesafe_cb.h>
+
+void _set_some_value(void *val);
+
+void _set_some_value(void *val)
+{
+}
+
+#define set_some_value(expr)						\
+	_set_some_value(typesafe_cb_cast(void *, unsigned long, (expr)))
+
+int main(int argc, char *argv[])
+{
+#ifdef FAIL
+	int x = 0;
+	set_some_value(x);
+#if !HAVE_TYPEOF||!HAVE_BUILTIN_CHOOSE_EXPR||!HAVE_BUILTIN_TYPES_COMPATIBLE_P
+#error "Unfortunately we don't fail if typesafe_cb_cast is a noop."
+#endif
+#else
+	void *p = 0;
+	set_some_value(p);
+#endif
+	return 0;
+}
diff --git a/lib/ccan/typesafe_cb/test/compile_fail-typesafe_cb_exact.c b/lib/ccan/typesafe_cb/test/compile_fail-typesafe_cb_exact.c
new file mode 100644
index 0000000000..0f61d5decd
--- /dev/null
+++ b/lib/ccan/typesafe_cb/test/compile_fail-typesafe_cb_exact.c
@@ -0,0 +1,33 @@
+#include <ccan/typesafe_cb/typesafe_cb.h>
+#include <stdlib.h>
+
+static void _register_callback(void (*cb)(void *arg), const void *arg)
+{
+}
+
+#define register_callback(cb, arg)				\
+	_register_callback(typesafe_cb_exact(void, (cb), (arg)), (arg))
+
+static void my_callback(const char *p)
+{
+}
+
+int main(int argc, char *argv[])
+{
+#ifdef FAIL
+	char *p;
+#if !HAVE_TYPEOF||!HAVE_BUILTIN_CHOOSE_EXPR||!HAVE_BUILTIN_TYPES_COMPATIBLE_P
+#error "Unfortunately we don't fail if cast_if_type is a noop."
+#endif
+#else
+	const char *p;
+#endif
+	p = NULL;
+
+	/* This should work always. */
+	register_callback(my_callback, (const char *)"hello world");
+
+	/* This will fail with FAIL defined */
+	register_callback(my_callback, p);
+	return 0;
+}
diff --git a/lib/ccan/typesafe_cb/test/compile_fail-typesafe_cb_postargs.c b/lib/ccan/typesafe_cb/test/compile_fail-typesafe_cb_postargs.c
new file mode 100644
index 0000000000..7d3530851d
--- /dev/null
+++ b/lib/ccan/typesafe_cb/test/compile_fail-typesafe_cb_postargs.c
@@ -0,0 +1,27 @@
+#include <ccan/typesafe_cb/typesafe_cb.h>
+#include <stdlib.h>
+
+static void _register_callback(void (*cb)(void *arg, int x), void *arg)
+{
+}
+#define register_callback(cb, arg)				\
+	_register_callback(typesafe_cb_postargs(void, void *, (cb), (arg), int), (arg))
+
+static void my_callback(char *p, int x)
+{
+}
+
+int main(int argc, char *argv[])
+{
+#ifdef FAIL
+	int *p;
+#if !HAVE_TYPEOF||!HAVE_BUILTIN_CHOOSE_EXPR||!HAVE_BUILTIN_TYPES_COMPATIBLE_P
+#error "Unfortunately we don't fail if typesafe_cb_cast is a noop."
+#endif
+#else
+	char *p;
+#endif
+	p = NULL;
+	register_callback(my_callback, p);
+	return 0;
+}
diff --git a/lib/ccan/typesafe_cb/test/compile_fail-typesafe_cb_preargs.c b/lib/ccan/typesafe_cb/test/compile_fail-typesafe_cb_preargs.c
new file mode 100644
index 0000000000..bd55c6722c
--- /dev/null
+++ b/lib/ccan/typesafe_cb/test/compile_fail-typesafe_cb_preargs.c
@@ -0,0 +1,28 @@
+#include <ccan/typesafe_cb/typesafe_cb.h>
+#include <stdlib.h>
+
+static void _register_callback(void (*cb)(int x, void *arg), void *arg)
+{
+}
+
+#define register_callback(cb, arg)				\
+	_register_callback(typesafe_cb_preargs(void, void *, (cb), (arg), int), (arg))
+
+static void my_callback(int x, char *p)
+{
+}
+
+int main(int argc, char *argv[])
+{
+#ifdef FAIL
+	int *p;
+#if !HAVE_TYPEOF||!HAVE_BUILTIN_CHOOSE_EXPR||!HAVE_BUILTIN_TYPES_COMPATIBLE_P
+#error "Unfortunately we don't fail if typesafe_cb_cast is a noop."
+#endif
+#else
+	char *p;
+#endif
+	p = NULL;
+	register_callback(my_callback, p);
+	return 0;
+}
diff --git a/lib/ccan/typesafe_cb/test/compile_ok-cast_if_any.c b/lib/ccan/typesafe_cb/test/compile_ok-cast_if_any.c
new file mode 100644
index 0000000000..e8f3c49406
--- /dev/null
+++ b/lib/ccan/typesafe_cb/test/compile_ok-cast_if_any.c
@@ -0,0 +1,41 @@
+#include <ccan/typesafe_cb/typesafe_cb.h>
+#include <stdlib.h>
+
+struct foo {
+	int x;
+};
+
+struct bar {
+	int x;
+};
+
+struct baz {
+	int x;
+};
+
+struct any {
+	int x;
+};
+
+static void take_any(struct any *any)
+{
+}
+
+int main(int argc, char *argv[])
+{
+#if HAVE_TYPEOF
+	/* Otherwise we get unused warnings for these. */
+	struct foo *foo = NULL;
+	struct bar *bar = NULL;
+	struct baz *baz = NULL;
+#endif
+	struct other *arg = NULL;
+
+	take_any(cast_if_any(struct any *, arg, foo,
+			     struct foo *, struct bar *, struct baz *));
+	take_any(cast_if_any(struct any *, arg, bar,
+			     struct foo *, struct bar *, struct baz *));
+	take_any(cast_if_any(struct any *, arg, baz,
+			     struct foo *, struct bar *, struct baz *));
+	return 0;
+}
diff --git a/lib/ccan/typesafe_cb/test/compile_ok-typesafe_cb-NULL.c b/lib/ccan/typesafe_cb/test/compile_ok-typesafe_cb-NULL.c
new file mode 100644
index 0000000000..265de8b14e
--- /dev/null
+++ b/lib/ccan/typesafe_cb/test/compile_ok-typesafe_cb-NULL.c
@@ -0,0 +1,17 @@
+#include <ccan/typesafe_cb/typesafe_cb.h>
+#include <stdlib.h>
+
+/* NULL args for callback function should be OK for normal and _def. */
+
+static void _register_callback(void (*cb)(const void *arg), const void *arg)
+{
+}
+
+#define register_callback(cb, arg)				\
+	_register_callback(typesafe_cb(void, const void *, (cb), (arg)), (arg))
+
+int main(int argc, char *argv[])
+{
+	register_callback(NULL, "hello world");
+	return 0;
+}
diff --git a/lib/ccan/typesafe_cb/test/compile_ok-typesafe_cb-const.c b/lib/ccan/typesafe_cb/test/compile_ok-typesafe_cb-const.c
new file mode 100644
index 0000000000..7c2d62ef23
--- /dev/null
+++ b/lib/ccan/typesafe_cb/test/compile_ok-typesafe_cb-const.c
@@ -0,0 +1,50 @@
+#include <ccan/typesafe_cb/typesafe_cb.h>
+#include <stdlib.h>
+
+/* const args in callbacks should be OK. */
+
+static void _register_callback(void (*cb)(void *arg), void *arg)
+{
+}
+
+#define register_callback(cb, arg)				\
+	_register_callback(typesafe_cb(void, (cb), (arg)), (arg))
+
+#define register_callback_def(cb, arg)				\
+	_register_callback(typesafe_cb_def(void, (cb), (arg)), (arg))
+
+static void _register_callback_pre(void (*cb)(int x, void *arg), void *arg)
+{
+}
+
+#define register_callback_pre(cb, arg)					\
+	_register_callback_pre(typesafe_cb_preargs(void, (cb), (arg), int), (arg))
+
+static void _register_callback_post(void (*cb)(void *arg, int x), void *arg)
+{
+}
+
+#define register_callback_post(cb, arg)					\
+	_register_callback_post(typesafe_cb_postargs(void, (cb), (arg), int), (arg))
+
+static void my_callback(const char *p)
+{
+}
+
+static void my_callback_pre(int x, /*const*/ char *p)
+{
+}
+
+static void my_callback_post(/*const*/ char *p, int x)
+{
+}
+
+int main(int argc, char *argv[])
+{
+	char p[] = "hello world";
+	register_callback(my_callback, p);
+	register_callback_def(my_callback, p);
+	register_callback_pre(my_callback_pre, p);
+	register_callback_post(my_callback_post, p);
+	return 0;
+}
diff --git a/lib/ccan/typesafe_cb/test/compile_ok-typesafe_cb-undefined.c b/lib/ccan/typesafe_cb/test/compile_ok-typesafe_cb-undefined.c
new file mode 100644
index 0000000000..aa50bad6a9
--- /dev/null
+++ b/lib/ccan/typesafe_cb/test/compile_ok-typesafe_cb-undefined.c
@@ -0,0 +1,49 @@
+#include <ccan/typesafe_cb/typesafe_cb.h>
+#include <stdlib.h>
+
+/* const args in callbacks should be OK. */
+
+static void _register_callback(void (*cb)(void *arg), void *arg)
+{
+}
+
+#define register_callback(cb, arg)				\
+	_register_callback(typesafe_cb(void, void *, (cb), (arg)), (arg))
+
+static void _register_callback_pre(void (*cb)(int x, void *arg), void *arg)
+{
+}
+
+#define register_callback_pre(cb, arg)					\
+	_register_callback_pre(typesafe_cb_preargs(void, void *, (cb), (arg), int), (arg))
+
+static void _register_callback_post(void (*cb)(void *arg, int x), void *arg)
+{
+}
+
+#define register_callback_post(cb, arg)					\
+	_register_callback_post(typesafe_cb_postargs(void, void *, (cb), (arg), int), (arg))
+
+struct undefined;
+
+static void my_callback(struct undefined *undef)
+{
+}
+
+static void my_callback_pre(int x, struct undefined *undef)
+{
+}
+
+static void my_callback_post(struct undefined *undef, int x)
+{
+}
+
+int main(int argc, char *argv[])
+{
+	struct undefined *handle = NULL;
+
+	register_callback(my_callback, handle);
+	register_callback_pre(my_callback_pre, handle);
+	register_callback_post(my_callback_post, handle);
+	return 0;
+}
diff --git a/lib/ccan/typesafe_cb/test/compile_ok-typesafe_cb-vars.c b/lib/ccan/typesafe_cb/test/compile_ok-typesafe_cb-vars.c
new file mode 100644
index 0000000000..f6a2bfecbc
--- /dev/null
+++ b/lib/ccan/typesafe_cb/test/compile_ok-typesafe_cb-vars.c
@@ -0,0 +1,52 @@
+#include <ccan/typesafe_cb/typesafe_cb.h>
+#include <stdlib.h>
+
+/* const args in callbacks should be OK. */
+
+static void _register_callback(void (*cb)(void *arg), void *arg)
+{
+}
+
+#define register_callback(cb, arg)				\
+	_register_callback(typesafe_cb(void, void *, (cb), (arg)), (arg))
+
+static void _register_callback_pre(void (*cb)(int x, void *arg), void *arg)
+{
+}
+
+#define register_callback_pre(cb, arg)					\
+	_register_callback_pre(typesafe_cb_preargs(void, void *, (cb), (arg), int), (arg))
+
+static void _register_callback_post(void (*cb)(void *arg, int x), void *arg)
+{
+}
+
+#define register_callback_post(cb, arg)					\
+	_register_callback_post(typesafe_cb_postargs(void, void *, (cb), (arg), int), (arg))
+
+struct undefined;
+
+static void my_callback(struct undefined *undef)
+{
+}
+
+static void my_callback_pre(int x, struct undefined *undef)
+{
+}
+
+static void my_callback_post(struct undefined *undef, int x)
+{
+}
+
+int main(int argc, char *argv[])
+{
+	struct undefined *handle = NULL;
+	void (*cb)(struct undefined *undef) = my_callback;
+	void (*pre)(int x, struct undefined *undef) = my_callback_pre;
+	void (*post)(struct undefined *undef, int x) = my_callback_post;
+
+	register_callback(cb, handle);
+	register_callback_pre(pre, handle);
+	register_callback_post(post, handle);
+	return 0;
+}
diff --git a/lib/ccan/typesafe_cb/test/compile_ok-typesafe_cb-volatile.c b/lib/ccan/typesafe_cb/test/compile_ok-typesafe_cb-volatile.c
new file mode 100644
index 0000000000..3fcb1ff656
--- /dev/null
+++ b/lib/ccan/typesafe_cb/test/compile_ok-typesafe_cb-volatile.c
@@ -0,0 +1,47 @@
+#include <ccan/typesafe_cb/typesafe_cb.h>
+#include <stdlib.h>
+
+/* volatile args in callbacks should be OK. */
+
+static void _register_callback(void (*cb)(void *arg), void *arg)
+{
+}
+
+#define register_callback(cb, arg)				\
+	_register_callback(typesafe_cb(void, (cb), (arg)), (arg))
+
+static void _register_callback_pre(void (*cb)(int x, void *arg), void *arg)
+{
+}
+
+#define register_callback_pre(cb, arg)					\
+	_register_callback_pre(typesafe_cb_preargs(void, (cb), (arg), int), (arg))
+
+static void _register_callback_post(void (*cb)(void *arg, int x), void *arg)
+{
+}
+
+#define register_callback_post(cb, arg)					\
+	_register_callback_post(typesafe_cb_postargs(void, (cb), (arg), int), (arg))
+
+static void my_callback(volatile char *p)
+{
+}
+
+/* FIXME: Can't handle volatile for these */
+static void my_callback_pre(int x, /* volatile */ char *p)
+{
+}
+
+static void my_callback_post(/* volatile */ char *p, int x)
+{
+}
+
+int main(int argc, char *argv[])
+{
+	char p[] = "hello world";
+	register_callback(my_callback, p);
+	register_callback_pre(my_callback_pre, p);
+	register_callback_post(my_callback_post, p);
+	return 0;
+}
diff --git a/lib/ccan/typesafe_cb/test/compile_ok-typesafe_cb_cast.c b/lib/ccan/typesafe_cb/test/compile_ok-typesafe_cb_cast.c
new file mode 100644
index 0000000000..b7f21dc094
--- /dev/null
+++ b/lib/ccan/typesafe_cb/test/compile_ok-typesafe_cb_cast.c
@@ -0,0 +1,41 @@
+#include <ccan/typesafe_cb/typesafe_cb.h>
+#include <stdlib.h>
+
+struct foo {
+	int x;
+};
+
+struct bar {
+	int x;
+};
+
+struct baz {
+	int x;
+};
+
+struct any {
+	int x;
+};
+
+static void take_any(struct any *any)
+{
+}
+
+int main(int argc, char *argv[])
+{
+	/* Otherwise we get unused warnings for these. */
+	struct foo *foo = NULL;
+	struct bar *bar = NULL;
+	struct baz *baz = NULL;
+
+	take_any(typesafe_cb_cast3(struct any *,
+				   struct foo *, struct bar *, struct baz *,
+				   foo));
+	take_any(typesafe_cb_cast3(struct any *,
+				   struct foo *, struct bar *, struct baz *,
+				   bar));
+	take_any(typesafe_cb_cast3(struct any *,
+				   struct foo *, struct bar *, struct baz *,
+				   baz));
+	return 0;
+}
diff --git a/lib/ccan/typesafe_cb/test/compile_ok-typesafe_cb_def-const.c b/lib/ccan/typesafe_cb/test/compile_ok-typesafe_cb_def-const.c
new file mode 100644
index 0000000000..01e090f1dc
--- /dev/null
+++ b/lib/ccan/typesafe_cb/test/compile_ok-typesafe_cb_def-const.c
@@ -0,0 +1,46 @@
+#include <ccan/typesafe_cb/typesafe_cb.h>
+#include <stdlib.h>
+
+/* const args in callbacks should be OK. */
+
+static void _register_callback(void (*cb)(void *arg), void *arg)
+{
+}
+
+#define register_callback(cb, arg)				\
+	_register_callback(typesafe_cb(void, (cb), (arg)), (arg))
+
+static void _register_callback_pre(void (*cb)(int x, void *arg), void *arg)
+{
+}
+
+#define register_callback_pre(cb, arg)					\
+	_register_callback_pre(typesafe_cb_preargs(void, (cb), (arg), int), (arg))
+
+static void _register_callback_post(void (*cb)(void *arg, int x), void *arg)
+{
+}
+
+#define register_callback_post(cb, arg)					\
+	_register_callback_post(typesafe_cb_postargs(void, (cb), (arg), int), (arg))
+
+static void my_callback(const char *p)
+{
+}
+
+static void my_callback_pre(int x, /*const*/ char *p)
+{
+}
+
+static void my_callback_post(/*const*/ char *p, int x)
+{
+}
+
+int main(int argc, char *argv[])
+{
+	char p[] = "hello world";
+	register_callback(my_callback, p);
+	register_callback_pre(my_callback_pre, p);
+	register_callback_post(my_callback_post, p);
+	return 0;
+}
diff --git a/lib/ccan/typesafe_cb/test/run.c b/lib/ccan/typesafe_cb/test/run.c
new file mode 100644
index 0000000000..116e7d1946
--- /dev/null
+++ b/lib/ccan/typesafe_cb/test/run.c
@@ -0,0 +1,109 @@
+#include <ccan/typesafe_cb/typesafe_cb.h>
+#include <string.h>
+#include <stdint.h>
+#include <ccan/tap/tap.h>
+
+static char dummy = 0;
+
+/* The example usage. */
+static void _set_some_value(void *val)
+{
+	ok1(val == &dummy);
+}
+
+#define set_some_value(expr)						\
+	_set_some_value(typesafe_cb_cast(void *, unsigned long, (expr)))
+
+static void _callback_onearg(void (*fn)(void *arg), void *arg)
+{
+	fn(arg);
+}
+
+static void _callback_preargs(void (*fn)(int a, int b, void *arg), void *arg)
+{
+	fn(1, 2, arg);
+}
+
+static void _callback_postargs(void (*fn)(void *arg, int a, int b), void *arg)
+{
+	fn(arg, 1, 2);
+}
+
+#define callback_onearg(cb, arg)					\
+	_callback_onearg(typesafe_cb(void, void *, (cb), (arg)), (arg))
+
+#define callback_preargs(cb, arg)					\
+	_callback_preargs(typesafe_cb_preargs(void, void *, (cb), (arg), int, int), (arg))
+
+#define callback_postargs(cb, arg)					\
+	_callback_postargs(typesafe_cb_postargs(void, void *, (cb), (arg), int, int), (arg))
+
+static void my_callback_onearg(char *p)
+{
+	ok1(strcmp(p, "hello world") == 0);
+}
+
+static void my_callback_preargs(int a, int b, char *p)
+{
+	ok1(a == 1);
+	ok1(b == 2);
+	ok1(strcmp(p, "hello world") == 0);
+}
+
+static void my_callback_postargs(char *p, int a, int b)
+{
+	ok1(a == 1);
+	ok1(b == 2);
+	ok1(strcmp(p, "hello world") == 0);
+}
+
+/* This is simply a compile test; we promised typesafe_cb_cast can be in a
+ * static initializer. */
+struct callback_onearg
+{
+	void (*fn)(void *arg);
+	const void *arg;
+};
+
+struct callback_onearg cb_onearg
+= { typesafe_cb(void, void *, my_callback_onearg, (char *)(intptr_t)"hello world"),
+    "hello world" };
+
+struct callback_preargs
+{
+	void (*fn)(int a, int b, void *arg);
+	const void *arg;
+};
+
+struct callback_preargs cb_preargs
+= { typesafe_cb_preargs(void, void *, my_callback_preargs,
+			(char *)(intptr_t)"hi", int, int), "hi" };
+
+struct callback_postargs
+{
+	void (*fn)(void *arg, int a, int b);
+	const void *arg;
+};
+
+struct callback_postargs cb_postargs
+= { typesafe_cb_postargs(void, void *, my_callback_postargs,
+			 (char *)(intptr_t)"hi", int, int), "hi" };
+
+int main(int argc, char *argv[])
+{
+	void *p = &dummy;
+	unsigned long l = (unsigned long)p;
+	char str[] = "hello world";
+
+	plan_tests(2 + 1 + 3 + 3);
+	set_some_value(p);
+	set_some_value(l);
+
+	callback_onearg(my_callback_onearg, str);
+
+	callback_preargs(my_callback_preargs, str);
+
+	callback_postargs(my_callback_postargs, str);
+
+	return exit_status();
+}
diff --git a/lib/ccan/typesafe_cb/typesafe_cb.h b/lib/ccan/typesafe_cb/typesafe_cb.h
new file mode 100644
index 0000000000..40cfa39798
--- /dev/null
+++ b/lib/ccan/typesafe_cb/typesafe_cb.h
@@ -0,0 +1,133 @@
+#ifndef CCAN_TYPESAFE_CB_H
+#define CCAN_TYPESAFE_CB_H
+#include "config.h"
+
+#if HAVE_TYPEOF && HAVE_BUILTIN_CHOOSE_EXPR && HAVE_BUILTIN_TYPES_COMPATIBLE_P
+/**
+ * typesafe_cb_cast - only cast an expression if it matches a given type
+ * @desttype: the type to cast to
+ * @oktype: the type we allow
+ * @expr: the expression to cast
+ *
+ * This macro is used to create functions which allow multiple types.
+ * The result of this macro is used somewhere that a @desttype type is
+ * expected: if @expr is exactly of type @oktype, then it will be
+ * cast to @desttype type, otherwise left alone.
+ *
+ * This macro can be used in static initializers.
+ *
+ * This is merely useful for warnings: if the compiler does not
+ * support the primitives required for typesafe_cb_cast(), it becomes an
+ * unconditional cast, and the @oktype argument is not used.  In
+ * particular, this means that @oktype can be a type which uses the
+ * "typeof": it will not be evaluated if typeof is not supported.
+ *
+ * Example:
+ *	// We can take either an unsigned long or a void *.
+ *	void _set_some_value(void *val);
+ *	#define set_some_value(e)			\
+ *		_set_some_value(typesafe_cb_cast(void *, (e), unsigned long))
+ */
+#define typesafe_cb_cast(desttype, oktype, expr)			\
+	__builtin_choose_expr(						\
+		__builtin_types_compatible_p(__typeof__(0?(expr):(expr)), \
+					     oktype),			\
+		(desttype)(expr), (expr))
+#else
+#define typesafe_cb_cast(desttype, oktype, expr) ((desttype)(expr))
+#endif
+
+/**
+ * typesafe_cb_cast3 - only cast an expression if it matches given types
+ * @desttype: the type to cast to
+ * @ok1: the first type we allow
+ * @ok2: the second type we allow
+ * @ok3: the third type we allow
+ * @expr: the expression to cast
+ *
+ * This is a convenient wrapper for multiple typesafe_cb_cast() calls.
+ * You can chain them inside each other (ie. use typesafe_cb_cast()
+ * for expr) if you need more than 3 arguments.
+ *
+ * Example:
+ *	// We can take either a long, unsigned long, void * or a const void *.
+ *	void _set_some_value(void *val);
+ *	#define set_some_value(expr)					\
+ *		_set_some_value(typesafe_cb_cast3(void *,,		\
+ *					    long, unsigned long, const void *,\
+ *					    (expr)))
+ */
+#define typesafe_cb_cast3(desttype, ok1, ok2, ok3, expr)		\
+	typesafe_cb_cast(desttype, ok1,					\
+			 typesafe_cb_cast(desttype, ok2,		\
+					  typesafe_cb_cast(desttype, ok3, \
+							   (expr))))
+
+/**
+ * typesafe_cb - cast a callback function if it matches the arg
+ * @rtype: the return type of the callback function
+ * @atype: the (pointer) type which the callback function expects.
+ * @fn: the callback function to cast
+ * @arg: the (pointer) argument to hand to the callback function.
+ *
+ * If a callback function takes a single argument, this macro does
+ * appropriate casts to a function which takes a single atype argument if the
+ * callback provided matches the @arg.
+ *
+ * It is assumed that @arg is of pointer type: usually @arg is passed
+ * or assigned to a void * elsewhere anyway.
+ *
+ * Example:
+ *	void _register_callback(void (*fn)(void *arg), void *arg);
+ *	#define register_callback(fn, arg) \
+ *		_register_callback(typesafe_cb(void, (fn), void*, (arg)), (arg))
+ */
+#define typesafe_cb(rtype, atype, fn, arg)			\
+	typesafe_cb_cast(rtype (*)(atype),			\
+			 rtype (*)(__typeof__(arg)),		\
+			 (fn))
+
+/**
+ * typesafe_cb_preargs - cast a callback function if it matches the arg
+ * @rtype: the return type of the callback function
+ * @atype: the (pointer) type which the callback function expects.
+ * @fn: the callback function to cast
+ * @arg: the (pointer) argument to hand to the callback function.
+ *
+ * This is a version of typesafe_cb() for callbacks that take other arguments
+ * before the @arg.
+ *
+ * Example:
+ *	void _register_callback(void (*fn)(int, void *arg), void *arg);
+ *	#define register_callback(fn, arg)				   \
+ *		_register_callback(typesafe_cb_preargs(void, (fn), void *, \
+ *				   (arg), int),				   \
+ *				   (arg))
+ */
+#define typesafe_cb_preargs(rtype, atype, fn, arg, ...)			\
+	typesafe_cb_cast(rtype (*)(__VA_ARGS__, atype),			\
+			 rtype (*)(__VA_ARGS__, __typeof__(arg)),	\
+			 (fn))
+
+/**
+ * typesafe_cb_postargs - cast a callback function if it matches the arg
+ * @rtype: the return type of the callback function
+ * @atype: the (pointer) type which the callback function expects.
+ * @fn: the callback function to cast
+ * @arg: the (pointer) argument to hand to the callback function.
+ *
+ * This is a version of typesafe_cb() for callbacks that take other arguments
+ * after the @arg.
+ *
+ * Example:
+ *	void _register_callback(void (*fn)(void *arg, int), void *arg);
+ *	#define register_callback(fn, arg) \
+ *		_register_callback(typesafe_cb_postargs(void, (fn), void *, \
+ *				   (arg), int),				    \
+ *				   (arg))
+ */
+#define typesafe_cb_postargs(rtype, atype, fn, arg, ...)		\
+	typesafe_cb_cast(rtype (*)(atype, __VA_ARGS__),			\
+			 rtype (*)(__typeof__(arg), __VA_ARGS__),	\
+			 (fn))
+#endif /* CCAN_CAST_IF_TYPE_H */
diff --git a/lib/ccan/wscript b/lib/ccan/wscript
new file mode 100644
index 0000000000..0543a4de07
--- /dev/null
+++ b/lib/ccan/wscript
@@ -0,0 +1,120 @@
+#!/usr/bin/env python
+
+import Logs, sys
+
+def configure(conf):
+    # FIXME: if they don't have -Werror, these will all fail.  But they
+    # probably will anyway...
+    conf.CHECK_CODE('int __attribute__((cold)) func(int x) { return x; }',
+                    addmain=False, link=False, cflags="-Werror",
+                    define='HAVE_ATTRIBUTE_COLD')
+    conf.CHECK_CODE('int __attribute__((const)) func(int x) { return x; }',
+                    addmain=False, link=False, cflags="-Werror",
+                    define='HAVE_ATTRIBUTE_CONST')
+    conf.CHECK_CODE('void __attribute__((noreturn)) func(int x) { exit(x); }',
+                    addmain=False, link=False, cflags="-Werror",
+                    define='HAVE_ATTRIBUTE_NORETURN')
+    conf.CHECK_CODE('void __attribute__((format(__printf__, 1, 2))) func(const char *fmt, ...) { }',
+                    addmain=False, link=False, cflags="-Werror",
+                    define='HAVE_ATTRIBUTE_PRINTF')
+    conf.CHECK_CODE('int __attribute__((unused)) func(int x) { return x; }',
+                    addmain=False, link=False, cflags="-Werror",
+                    define='HAVE_ATTRIBUTE_UNUSED')
+    conf.CHECK_CODE('int __attribute__((used)) func(int x) { return x; }',
+                    addmain=False, link=False, cflags="-Werror",
+                    define='HAVE_ATTRIBUTE_USED')
+    # We try to use headers for a compile-time test.
+    conf.CHECK_CODE(code = """#ifdef __BYTE_ORDER
+                        #define B __BYTE_ORDER
+                        #elif defined(BYTE_ORDER)
+                        #define B BYTE_ORDER
+                        #endif
+
+                        #ifdef __LITTLE_ENDIAN
+                        #define LITTLE __LITTLE_ENDIAN
+                        #elif defined(LITTLE_ENDIAN)
+                        #define LITTLE LITTLE_ENDIAN
+                        #endif
+
+                        #if !defined(LITTLE) || !defined(B) || LITTLE != B
+                        #error Not little endian.
+                        #endif""",
+                           headers="endian.h sys/endian.h",
+                           define="HAVE_LITTLE_ENDIAN")
+    conf.CHECK_CODE(code = """#ifdef __BYTE_ORDER
+                        #define B __BYTE_ORDER
+                        #elif defined(BYTE_ORDER)
+                        #define B BYTE_ORDER
+                        #endif
+
+                        #ifdef __BIG_ENDIAN
+                        #define BIG __BIG_ENDIAN
+                        #elif defined(BIG_ENDIAN)
+                        #define BIG BIG_ENDIAN
+                        #endif
+
+                        #if !defined(BIG) || !defined(B) || BIG != B
+                        #error Not big endian.
+                        #endif""",
+                           headers="endian.h sys/endian.h",
+                           define="HAVE_BIG_ENDIAN")
+
+    if not conf.CONFIG_SET("HAVE_BIG_ENDIAN") and not conf.CONFIG_SET("HAVE_LITTLE_ENDIAN"):
+        # That didn't work!  Do runtime test.
+        conf.CHECK_CODE("""union { int i; char c[sizeof(int)]; } u;
+	  u.i = 0x01020304;
+	  return u.c[0] == 0x04 && u.c[1] == 0x03 && u.c[2] == 0x02 && u.c[3] == 0x01 ? 0 : 1;""",
+                        addmain=True, execute=True,
+                        define='HAVE_LITTLE_ENDIAN',
+                        msg="Checking for HAVE_LITTLE_ENDIAN - runtime")
+        conf.CHECK_CODE("""union { int i; char c[sizeof(int)]; } u;
+	  u.i = 0x01020304;
+	  return u.c[0] == 0x01 && u.c[1] == 0x02 && u.c[2] == 0x03 && u.c[3] == 0x04 ? 0 : 1;""",
+                        addmain=True, execute=True,
+                        define='HAVE_BIG_ENDIAN',
+                        msg="Checking for HAVE_BIG_ENDIAN - runtime")
+
+    # Extra sanity check.
+    if conf.CONFIG_SET("HAVE_BIG_ENDIAN") == conf.CONFIG_SET("HAVE_LITTLE_ENDIAN"):
+        Logs.error("Failed endian determination.  The PDP-11 is back?")
+        sys.exit(1)
+
+    conf.CHECK_CODE('return __builtin_clz(1) == (sizeof(int)*8 - 1) ? 0 : 1;',
+                    link=True,
+                    define='HAVE_BUILTIN_CLZ')
+    conf.CHECK_CODE('return __builtin_clzl(1) == (sizeof(long)*8 - 1) ? 0 : 1;',
+                    link=True,
+                    define='HAVE_BUILTIN_CLZL')
+    conf.CHECK_CODE('return __builtin_clzll(1) == (sizeof(long long)*8 - 1) ? 0 : 1;',
+                    link=True,
+                    define='HAVE_BUILTIN_CLZLL')
+    conf.CHECK_CODE('return __builtin_constant_p(1) ? 0 : 1;',
+                    link=True,
+                    define='HAVE_BUILTIN_CONSTANT_P')
+    conf.CHECK_CODE('return __builtin_expect(main != 0, 1) ? 0 : 1;',
+                    link=True,
+                    define='HAVE_BUILTIN_EXPECT')
+    conf.CHECK_CODE('return __builtin_popcountl(255L) == 8 ? 0 : 1;',
+                    link=True,
+                    define='HAVE_BUILTIN_POPCOUNTL')
+    conf.CHECK_CODE('return __builtin_types_compatible_p(char *, int) ? 1 : 0;',
+                    link=True,
+                    define='HAVE_BUILTIN_TYPES_COMPATIBLE_P')
+    conf.CHECK_CODE('int *foo = (int[]) { 1, 2, 3, 4 }; return foo[0] ? 0 : 1;',
+                    define='HAVE_COMPOUND_LITERALS')
+    conf.CHECK_CODE("""#include <ctype.h>
+	  int main(void) { return isblank(' ') ? 0 : 1; }""",
+                    link=True, addmain=False, add_headers=False,
+                    define='HAVE_ISBLANK')
+    conf.CHECK_CODE('int x = 1; __typeof__(x) i; i = x; return i == x ? 0 : 1;',
+                    link=True,
+                    define='HAVE_TYPEOF')
+    conf.CHECK_CODE('int __attribute__((warn_unused_result)) func(int x) { return x; }',
+                    addmain=False, link=False, cflags="-Werror",
+                    define='HAVE_WARN_UNUSED_RESULT')
+
+def build(bld):
+    bld.SAMBA_LIBRARY('ccan',
+                      vnum="0.1-init-1161-g661d41f",
+                      source=bld.path.ant_glob('*/*.c'),
+                      private_library=True)
diff --git a/source3/Makefile.in b/source3/Makefile.in
index 3df9ab47f6..9dd0a45c42 100644
--- a/source3/Makefile.in
+++ b/source3/Makefile.in
@@ -472,6 +472,7 @@ LIB_OBJ = $(LIBSAMBAUTIL_OBJ) $(UTIL_OBJ) $(CRYPTO_OBJ) \
 	  lib/conn_tdb.o lib/adt_tree.o lib/gencache.o \
 	  lib/sessionid_tdb.o \
 	  lib/module.o lib/events.o @LIBTEVENT_OBJ0@ \
+	  @CCAN_OBJ@ \
 	  lib/server_contexts.o \
 	  lib/ldap_escape.o @CHARSET_STATIC@ \
 	  ../libcli/security/secdesc.o ../libcli/security/access_check.o \
diff --git a/source3/configure.in b/source3/configure.in
index 324ada4c54..2d248cc4a5 100644
--- a/source3/configure.in
+++ b/source3/configure.in
@@ -26,6 +26,7 @@ AC_LIBREPLACE_CC_CHECKS
 AC_LIBREPLACE_RUNTIME_LIB_PATH_VAR
 
 m4_include(../lib/tevent/libtevent.m4)
+m4_include(../lib/ccan/libccan.m4)
 
 LIBTEVENT_OBJ0=""
 for obj in ${TEVENT_OBJ}; do
@@ -37,6 +38,7 @@ LIBS="${LIBS} ${TEVENT_LIBS}"
 SAMBA_CPPFLAGS="-Iinclude/autoconf -Iinclude -I${srcdir-.}/include  -I. -I${srcdir-.}"
 SAMBA_CPPFLAGS="${SAMBA_CPPFLAGS} -I${srcdir-.}/../lib/replace"
 SAMBA_CPPFLAGS="${SAMBA_CPPFLAGS} ${TEVENT_CFLAGS}"
+SAMBA_CPPFLAGS="${SAMBA_CPPFLAGS} ${CCAN_CFLAGS}"
 SAMBA_CPPFLAGS="${SAMBA_CPPFLAGS} -I${srcdir-.}/librpc"
 SAMBA_CPPFLAGS="${SAMBA_CPPFLAGS} -I${srcdir-.}/.."
 
diff --git a/source3/wscript b/source3/wscript
index 83b0a0ef04..4b5d98bbc3 100644
--- a/source3/wscript
+++ b/source3/wscript
@@ -92,6 +92,7 @@ def configure(conf):
     if not conf.env.toplevel_build:
         conf.RECURSE('../lib/replace')
         conf.RECURSE('build')
+        conf.RECURSE('../lib/ccan')
         conf.RECURSE('../lib/tdb')
         conf.RECURSE('../lib/talloc')
         conf.RECURSE('../lib/tevent')
@@ -102,7 +103,7 @@ def configure(conf):
         conf.RECURSE('../libcli/smbreadline')
         conf.RECURSE('../lib/util')
 
-        conf.ADD_EXTRA_INCLUDES('''#source3 #source3/include #lib/replace''')
+        conf.ADD_EXTRA_INCLUDES('''#source3 #source3/include #lib/replace #lib''')
         if not conf.env.USING_SYSTEM_TDB:
             conf.ADD_EXTRA_INCLUDES('#lib/tdb/include')
         if not conf.env.USING_SYSTEM_TEVENT:
diff --git a/source3/wscript_build b/source3/wscript_build
index e3160e6913..df38e4c9db 100755
--- a/source3/wscript_build
+++ b/source3/wscript_build
@@ -1425,6 +1425,7 @@ bld.RECURSE('../auth')
 bld.RECURSE('../auth/kerberos')
 bld.RECURSE('../lib/addns')
 bld.RECURSE('../lib/async_req')
+bld.RECURSE('../lib/ccan')
 bld.RECURSE('../lib/socket')
 bld.RECURSE('../libcli/auth')
 bld.RECURSE('../libcli/drsuapi')
diff --git a/wscript b/wscript
index 8e1e9a6305..52d0ea4f44 100755
--- a/wscript
+++ b/wscript
@@ -95,6 +95,7 @@ def configure(conf):
     conf.RECURSE('source4/lib/tls')
     conf.RECURSE('source4/ntvfs/sysdep')
     conf.RECURSE('lib/util')
+    conf.RECURSE('lib/ccan')
     conf.RECURSE('lib/zlib')
     conf.RECURSE('lib/util/charset')
     conf.RECURSE('source4/auth')
diff --git a/wscript_build b/wscript_build
index b61a87e1c8..d42978ff66 100644
--- a/wscript_build
+++ b/wscript_build
@@ -37,6 +37,7 @@ bld.RECURSE('lib/socket')
 bld.RECURSE('lib/talloc')
 bld.RECURSE('lib/tdb')
 bld.RECURSE('lib/tevent')
+bld.RECURSE('lib/ccan')
 bld.RECURSE('source4/lib/ldb')
 bld.RECURSE('source4/dynconfig')
 bld.RECURSE('lib/util/charset')