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>

23 files changed, 1337 insertions, 0 deletions

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 @@
+
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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();
+}