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authorAndrew Tridgell <tridge@samba.org>2005-01-02 07:47:34 +0000
committerGerald (Jerry) Carter <jerry@samba.org>2007-10-10 13:07:55 -0500
commit65f96eba32b93ced0717c2639007bba59da55fa4 (patch)
treedc691fb43c8d1d0261497e53502a0e0b93ffd31c /source4/lib/talloc/talloc.c
parent68460ee88caadefea2adbd4f24755e3dd1cb0a47 (diff)
downloadsamba-65f96eba32b93ced0717c2639007bba59da55fa4.tar.gz
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r4473: - moved talloc into its own lib/talloc/ area
- added gcov flags to Makefile.talloc - expanded talloc testsuite to add a test for realloc with a child ptr - fixed a bug in talloc_realloc() with realloc of a ptr that has child ptrs (This used to be commit 98b5f73c1ba34d7576c5995069b485c1c5ede324)
Diffstat (limited to 'source4/lib/talloc/talloc.c')
-rw-r--r--source4/lib/talloc/talloc.c1006
1 files changed, 1006 insertions, 0 deletions
diff --git a/source4/lib/talloc/talloc.c b/source4/lib/talloc/talloc.c
new file mode 100644
index 0000000000..4666e28288
--- /dev/null
+++ b/source4/lib/talloc/talloc.c
@@ -0,0 +1,1006 @@
+/*
+ Samba Unix SMB/CIFS implementation.
+
+ Samba trivial allocation library - new interface
+
+ NOTE: Please read talloc_guide.txt for full documentation
+
+ Copyright (C) Andrew Tridgell 2004
+
+ 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
+ GNU General Public License for more details.
+
+ 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., 675 Mass Ave, Cambridge, MA 02139, USA.
+*/
+
+/*
+ inspired by http://swapped.cc/halloc/
+*/
+
+
+#ifdef _SAMBA_BUILD_
+#include "includes.h"
+#else
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <stdarg.h>
+#include <stdint.h>
+#include "talloc.h"
+#endif
+
+/* use this to force every realloc to change the pointer, to stress test
+ code that might not cope */
+#define ALWAYS_REALLOC 0
+
+
+#define MAX_TALLOC_SIZE 0x10000000
+#define TALLOC_MAGIC 0xe814ec4f
+#define TALLOC_MAGIC_FREE 0x7faebef3
+#define TALLOC_MAGIC_REFERENCE ((const char *)1)
+
+/* by default we abort when given a bad pointer (such as when talloc_free() is called
+ on a pointer that came from malloc() */
+#ifndef TALLOC_ABORT
+#define TALLOC_ABORT(reason) abort()
+#endif
+
+#ifndef discard_const_p
+#if defined(__intptr_t_defined) || defined(HAVE_INTPTR_T)
+# define discard_const_p(type, ptr) ((type *)((intptr_t)(ptr)))
+#else
+# define discard_const_p(type, ptr) ((type *)(ptr))
+#endif
+#endif
+
+/* this null_context is only used if talloc_enable_leak_report() or
+ talloc_enable_leak_report_full() is called, otherwise it remains
+ NULL
+*/
+static const void *null_context;
+
+
+struct talloc_reference_handle {
+ struct talloc_reference_handle *next, *prev;
+ void *ptr;
+};
+
+typedef int (*talloc_destructor_t)(void *);
+
+struct talloc_chunk {
+ struct talloc_chunk *next, *prev;
+ struct talloc_chunk *parent, *child;
+ struct talloc_reference_handle *refs;
+ size_t size;
+ unsigned magic;
+ talloc_destructor_t destructor;
+ const char *name;
+};
+
+/* panic if we get a bad magic value */
+static struct talloc_chunk *talloc_chunk_from_ptr(const void *ptr)
+{
+ struct talloc_chunk *tc = discard_const_p(struct talloc_chunk, ptr)-1;
+ if (tc->magic != TALLOC_MAGIC) {
+ if (tc->magic == TALLOC_MAGIC_FREE) {
+ TALLOC_ABORT("Bad talloc magic value - double free");
+ } else {
+ TALLOC_ABORT("Bad talloc magic value - unknown value");
+ }
+ }
+
+ return tc;
+}
+
+/* hook into the front of the list */
+#define _TLIST_ADD(list, p) \
+do { \
+ if (!(list)) { \
+ (list) = (p); \
+ (p)->next = (p)->prev = NULL; \
+ } else { \
+ (list)->prev = (p); \
+ (p)->next = (list); \
+ (p)->prev = NULL; \
+ (list) = (p); \
+ }\
+} while (0)
+
+/* remove an element from a list - element doesn't have to be in list. */
+#define _TLIST_REMOVE(list, p) \
+do { \
+ if ((p) == (list)) { \
+ (list) = (p)->next; \
+ if (list) (list)->prev = NULL; \
+ } else { \
+ if ((p)->prev) (p)->prev->next = (p)->next; \
+ if ((p)->next) (p)->next->prev = (p)->prev; \
+ } \
+ if ((p) && ((p) != (list))) (p)->next = (p)->prev = NULL; \
+} while (0)
+
+
+/*
+ return the parent chunk of a pointer
+*/
+static struct talloc_chunk *talloc_parent_chunk(const void *ptr)
+{
+ struct talloc_chunk *tc = talloc_chunk_from_ptr(ptr);
+ while (tc->prev) tc=tc->prev;
+ return tc->parent;
+}
+
+/*
+ Allocate a bit of memory as a child of an existing pointer
+*/
+void *_talloc(const void *context, size_t size)
+{
+ struct talloc_chunk *tc;
+
+ if (context == NULL) {
+ context = null_context;
+ }
+
+ if (size >= MAX_TALLOC_SIZE) {
+ return NULL;
+ }
+
+ tc = malloc(sizeof(*tc)+size);
+ if (tc == NULL) return NULL;
+
+ tc->size = size;
+ tc->magic = TALLOC_MAGIC;
+ tc->destructor = NULL;
+ tc->child = NULL;
+ tc->name = NULL;
+ tc->refs = NULL;
+
+ if (context) {
+ struct talloc_chunk *parent = talloc_chunk_from_ptr(context);
+
+ tc->parent = parent;
+
+ if (parent->child) {
+ parent->child->parent = NULL;
+ }
+
+ _TLIST_ADD(parent->child, tc);
+ } else {
+ tc->next = tc->prev = tc->parent = NULL;
+ }
+
+ return (void *)(tc+1);
+}
+
+
+/*
+ setup a destructor to be called on free of a pointer
+ the destructor should return 0 on success, or -1 on failure.
+ if the destructor fails then the free is failed, and the memory can
+ be continued to be used
+*/
+void talloc_set_destructor(const void *ptr, int (*destructor)(void *))
+{
+ struct talloc_chunk *tc = talloc_chunk_from_ptr(ptr);
+ tc->destructor = destructor;
+}
+
+/*
+ increase the reference count on a piece of memory.
+*/
+void talloc_increase_ref_count(const void *ptr)
+{
+ talloc_reference(null_context, ptr);
+}
+
+/*
+ helper for talloc_reference()
+*/
+static int talloc_reference_destructor(void *ptr)
+{
+ struct talloc_reference_handle *handle = ptr;
+ struct talloc_chunk *tc1 = talloc_chunk_from_ptr(ptr);
+ struct talloc_chunk *tc2 = talloc_chunk_from_ptr(handle->ptr);
+ if (tc1->destructor != (talloc_destructor_t)-1) {
+ tc1->destructor = NULL;
+ }
+ _TLIST_REMOVE(tc2->refs, handle);
+ talloc_free(handle);
+ return 0;
+}
+
+/*
+ make a secondary reference to a pointer, hanging off the given context.
+ the pointer remains valid until both the original caller and this given
+ context are freed.
+
+ the major use for this is when two different structures need to reference the
+ same underlying data, and you want to be able to free the two instances separately,
+ and in either order
+*/
+void *talloc_reference(const void *context, const void *ptr)
+{
+ struct talloc_chunk *tc;
+ struct talloc_reference_handle *handle;
+ if (ptr == NULL) return NULL;
+
+ tc = talloc_chunk_from_ptr(ptr);
+ handle = talloc_named_const(context, sizeof(*handle), TALLOC_MAGIC_REFERENCE);
+
+ if (handle == NULL) return NULL;
+
+ /* note that we hang the destructor off the handle, not the
+ main context as that allows the caller to still setup their
+ own destructor on the context if they want to */
+ talloc_set_destructor(handle, talloc_reference_destructor);
+ handle->ptr = discard_const_p(void, ptr);
+ _TLIST_ADD(tc->refs, handle);
+ return handle->ptr;
+}
+
+/*
+ remove a secondary reference to a pointer. This undo's what
+ talloc_reference() has done. The context and pointer arguments
+ must match those given to a talloc_reference()
+*/
+static int talloc_unreference(const void *context, const void *ptr)
+{
+ struct talloc_chunk *tc = talloc_chunk_from_ptr(ptr);
+ struct talloc_reference_handle *h;
+
+ if (context == NULL) {
+ context = null_context;
+ }
+
+ for (h=tc->refs;h;h=h->next) {
+ struct talloc_chunk *p = talloc_parent_chunk(h);
+ if ((p==NULL && context==NULL) || p+1 == context) break;
+ }
+ if (h == NULL) {
+ return -1;
+ }
+
+ talloc_set_destructor(h, NULL);
+ _TLIST_REMOVE(tc->refs, h);
+ talloc_free(h);
+ return 0;
+}
+
+/*
+ remove a specific parent context from a pointer. This is a more
+ controlled varient of talloc_free()
+*/
+int talloc_unlink(const void *context, void *ptr)
+{
+ struct talloc_chunk *tc_p, *new_p;
+ void *new_parent;
+
+ if (ptr == NULL) {
+ return -1;
+ }
+
+ if (context == NULL) {
+ context = null_context;
+ }
+
+ if (talloc_unreference(context, ptr) == 0) {
+ return 0;
+ }
+
+ if (context == NULL) {
+ if (talloc_parent_chunk(ptr) != NULL) {
+ return -1;
+ }
+ } else {
+ if (talloc_chunk_from_ptr(context) != talloc_parent_chunk(ptr)) {
+ return -1;
+ }
+ }
+
+ tc_p = talloc_chunk_from_ptr(ptr);
+
+ if (tc_p->refs == NULL) {
+ return talloc_free(ptr);
+ }
+
+ new_p = talloc_parent_chunk(tc_p->refs);
+ if (new_p) {
+ new_parent = new_p+1;
+ } else {
+ new_parent = NULL;
+ }
+
+ if (talloc_unreference(new_parent, ptr) != 0) {
+ return -1;
+ }
+
+ talloc_steal(new_parent, ptr);
+
+ return 0;
+}
+
+/*
+ add a name to an existing pointer - va_list version
+*/
+static void talloc_set_name_v(const void *ptr, const char *fmt, va_list ap) PRINTF_ATTRIBUTE(2,0);
+
+static void talloc_set_name_v(const void *ptr, const char *fmt, va_list ap)
+{
+ struct talloc_chunk *tc = talloc_chunk_from_ptr(ptr);
+ tc->name = talloc_vasprintf(ptr, fmt, ap);
+ if (tc->name) {
+ talloc_set_name_const(tc->name, ".name");
+ }
+}
+
+/*
+ add a name to an existing pointer
+*/
+void talloc_set_name(const void *ptr, const char *fmt, ...)
+{
+ va_list ap;
+ va_start(ap, fmt);
+ talloc_set_name_v(ptr, fmt, ap);
+ va_end(ap);
+}
+
+/*
+ more efficient way to add a name to a pointer - the name must point to a
+ true string constant
+*/
+void talloc_set_name_const(const void *ptr, const char *name)
+{
+ struct talloc_chunk *tc = talloc_chunk_from_ptr(ptr);
+ tc->name = name;
+}
+
+/*
+ create a named talloc pointer. Any talloc pointer can be named, and
+ talloc_named() operates just like talloc() except that it allows you
+ to name the pointer.
+*/
+void *talloc_named(const void *context, size_t size, const char *fmt, ...)
+{
+ va_list ap;
+ void *ptr;
+
+ ptr = _talloc(context, size);
+ if (ptr == NULL) return NULL;
+
+ va_start(ap, fmt);
+ talloc_set_name_v(ptr, fmt, ap);
+ va_end(ap);
+
+ return ptr;
+}
+
+/*
+ create a named talloc pointer. Any talloc pointer can be named, and
+ talloc_named() operates just like talloc() except that it allows you
+ to name the pointer.
+*/
+void *talloc_named_const(const void *context, size_t size, const char *name)
+{
+ void *ptr;
+
+ ptr = _talloc(context, size);
+ if (ptr == NULL) {
+ return NULL;
+ }
+
+ talloc_set_name_const(ptr, name);
+
+ return ptr;
+}
+
+/*
+ return the name of a talloc ptr, or "UNNAMED"
+*/
+const char *talloc_get_name(const void *ptr)
+{
+ struct talloc_chunk *tc = talloc_chunk_from_ptr(ptr);
+ if (tc->name == TALLOC_MAGIC_REFERENCE) {
+ return ".reference";
+ }
+ if (tc->name) {
+ return tc->name;
+ }
+ return "UNNAMED";
+}
+
+/*
+ this is for compatibility with older versions of talloc
+*/
+void *talloc_init(const char *fmt, ...)
+{
+ va_list ap;
+ void *ptr;
+
+ ptr = _talloc(NULL, 0);
+ if (ptr == NULL) return NULL;
+
+ va_start(ap, fmt);
+ talloc_set_name_v(ptr, fmt, ap);
+ va_end(ap);
+
+ return ptr;
+}
+
+
+/*
+ free a talloc pointer. This also frees all child pointers of this
+ pointer recursively
+
+ return 0 if the memory is actually freed, otherwise -1. The memory
+ will not be freed if the ref_count is > 1 or the destructor (if
+ any) returns non-zero
+*/
+int talloc_free(void *ptr)
+{
+ struct talloc_chunk *tc;
+
+ if (ptr == NULL) {
+ return -1;
+ }
+
+ tc = talloc_chunk_from_ptr(ptr);
+
+ if (tc->refs) {
+ talloc_reference_destructor(tc->refs);
+ return -1;
+ }
+
+ if (tc->destructor) {
+ talloc_destructor_t d = tc->destructor;
+ if (d == (talloc_destructor_t)-1) {
+ return -1;
+ }
+ tc->destructor = (talloc_destructor_t)-1;
+ if (d(ptr) == -1) {
+ tc->destructor = d;
+ return -1;
+ }
+ tc->destructor = NULL;
+ }
+
+ while (tc->child) {
+ /* we need to work out who will own an abandoned child
+ if it cannot be freed. In priority order, the first
+ choice is owner of any remaining reference to this
+ pointer, the second choice is our parent, and the
+ final choice is the null context. */
+ void *child = tc->child+1;
+ const void *new_parent = null_context;
+ if (tc->child->refs) {
+ struct talloc_chunk *p = talloc_parent_chunk(tc->child->refs);
+ if (p) new_parent = p+1;
+ }
+ if (talloc_free(child) == -1) {
+ if (new_parent == null_context) {
+ struct talloc_chunk *p = talloc_parent_chunk(ptr);
+ if (p) new_parent = p+1;
+ }
+ talloc_steal(new_parent, child);
+ }
+ }
+
+ if (tc->parent) {
+ _TLIST_REMOVE(tc->parent->child, tc);
+ if (tc->parent->child) {
+ tc->parent->child->parent = tc->parent;
+ }
+ } else {
+ if (tc->prev) tc->prev->next = tc->next;
+ if (tc->next) tc->next->prev = tc->prev;
+ }
+
+ tc->magic = TALLOC_MAGIC_FREE;
+
+ free(tc);
+ return 0;
+}
+
+
+
+/*
+ A talloc version of realloc. The context argument is only used if
+ ptr is NULL
+*/
+void *_talloc_realloc(const void *context, void *ptr, size_t size, const char *name)
+{
+ struct talloc_chunk *tc;
+ void *new_ptr;
+
+ /* size zero is equivalent to free() */
+ if (size == 0) {
+ talloc_free(ptr);
+ return NULL;
+ }
+
+ if (size >= MAX_TALLOC_SIZE) {
+ return NULL;
+ }
+
+ /* realloc(NULL) is equavalent to malloc() */
+ if (ptr == NULL) {
+ return talloc_named_const(context, size, name);
+ }
+
+ tc = talloc_chunk_from_ptr(ptr);
+
+ /* don't allow realloc on referenced pointers */
+ if (tc->refs) {
+ return NULL;
+ }
+
+ /* by resetting magic we catch users of the old memory */
+ tc->magic = TALLOC_MAGIC_FREE;
+
+#if ALWAYS_REALLOC
+ new_ptr = malloc(size + sizeof(*tc));
+ if (new_ptr) {
+ memcpy(new_ptr, tc, tc->size + sizeof(*tc));
+ free(tc);
+ }
+#else
+ new_ptr = realloc(tc, size + sizeof(*tc));
+#endif
+ if (!new_ptr) {
+ tc->magic = TALLOC_MAGIC;
+ return NULL;
+ }
+
+ tc = new_ptr;
+ tc->magic = TALLOC_MAGIC;
+ if (tc->parent) {
+ tc->parent->child = new_ptr;
+ }
+ if (tc->child) {
+ tc->child->parent = new_ptr;
+ }
+
+ if (tc->prev) {
+ tc->prev->next = tc;
+ }
+ if (tc->next) {
+ tc->next->prev = tc;
+ }
+
+ tc->size = size;
+ talloc_set_name_const(tc+1, name);
+
+ return (void *)(tc+1);
+}
+
+/*
+ move a lump of memory from one talloc context to another return the
+ ptr on success, or NULL if it could not be transferred
+*/
+void *talloc_steal(const void *new_ctx, const void *ptr)
+{
+ struct talloc_chunk *tc, *new_tc;
+
+ if (!ptr) {
+ return NULL;
+ }
+
+ if (new_ctx == NULL) {
+ new_ctx = null_context;
+ }
+
+ tc = talloc_chunk_from_ptr(ptr);
+
+ if (new_ctx == NULL) {
+ if (tc->parent) {
+ _TLIST_REMOVE(tc->parent->child, tc);
+ if (tc->parent->child) {
+ tc->parent->child->parent = tc->parent;
+ }
+ } else {
+ if (tc->prev) tc->prev->next = tc->next;
+ if (tc->next) tc->next->prev = tc->prev;
+ }
+
+ tc->parent = tc->next = tc->prev = NULL;
+ return discard_const_p(void, ptr);
+ }
+
+ new_tc = talloc_chunk_from_ptr(new_ctx);
+
+ if (tc == new_tc) {
+ return discard_const_p(void, ptr);
+ }
+
+ if (tc->parent) {
+ _TLIST_REMOVE(tc->parent->child, tc);
+ if (tc->parent->child) {
+ tc->parent->child->parent = tc->parent;
+ }
+ } else {
+ if (tc->prev) tc->prev->next = tc->next;
+ if (tc->next) tc->next->prev = tc->prev;
+ }
+
+ tc->parent = new_tc;
+ if (new_tc->child) new_tc->child->parent = NULL;
+ _TLIST_ADD(new_tc->child, tc);
+
+ return discard_const_p(void, ptr);
+}
+
+/*
+ return the total size of a talloc pool (subtree)
+*/
+off_t talloc_total_size(const void *ptr)
+{
+ off_t total = 0;
+ struct talloc_chunk *c, *tc;
+
+ if (ptr == NULL) {
+ ptr = null_context;
+ }
+ if (ptr == NULL) {
+ return 0;
+ }
+
+ tc = talloc_chunk_from_ptr(ptr);
+
+ total = tc->size;
+ for (c=tc->child;c;c=c->next) {
+ total += talloc_total_size(c+1);
+ }
+ return total;
+}
+
+/*
+ return the total number of blocks in a talloc pool (subtree)
+*/
+off_t talloc_total_blocks(const void *ptr)
+{
+ off_t total = 0;
+ struct talloc_chunk *c, *tc = talloc_chunk_from_ptr(ptr);
+
+ total++;
+ for (c=tc->child;c;c=c->next) {
+ total += talloc_total_blocks(c+1);
+ }
+ return total;
+}
+
+/*
+ return the number of external references to a pointer
+*/
+static int talloc_reference_count(const void *ptr)
+{
+ struct talloc_chunk *tc = talloc_chunk_from_ptr(ptr);
+ struct talloc_reference_handle *h;
+ int ret = 0;
+
+ for (h=tc->refs;h;h=h->next) {
+ ret++;
+ }
+ return ret;
+}
+
+/*
+ report on memory usage by all children of a pointer, giving a full tree view
+*/
+static void talloc_report_depth(const void *ptr, FILE *f, int depth)
+{
+ struct talloc_chunk *c, *tc = talloc_chunk_from_ptr(ptr);
+
+ for (c=tc->child;c;c=c->next) {
+ if (c->name == TALLOC_MAGIC_REFERENCE) {
+ struct talloc_reference_handle *handle = (void *)(c+1);
+ const char *name2 = talloc_get_name(handle->ptr);
+ fprintf(f, "%*sreference to: %s\n", depth*4, "", name2);
+ } else {
+ const char *name = talloc_get_name(c+1);
+ fprintf(f, "%*s%-30s contains %6lu bytes in %3lu blocks (ref %d)\n",
+ depth*4, "",
+ name,
+ (unsigned long)talloc_total_size(c+1),
+ (unsigned long)talloc_total_blocks(c+1),
+ talloc_reference_count(c+1));
+ talloc_report_depth(c+1, f, depth+1);
+ }
+ }
+
+}
+
+/*
+ report on memory usage by all children of a pointer, giving a full tree view
+*/
+void talloc_report_full(const void *ptr, FILE *f)
+{
+ if (ptr == NULL) {
+ ptr = null_context;
+ }
+ if (ptr == NULL) return;
+
+ fprintf(f,"full talloc report on '%s' (total %lu bytes in %lu blocks)\n",
+ talloc_get_name(ptr),
+ (unsigned long)talloc_total_size(ptr),
+ (unsigned long)talloc_total_blocks(ptr));
+
+ talloc_report_depth(ptr, f, 1);
+}
+
+/*
+ report on memory usage by all children of a pointer
+*/
+void talloc_report(const void *ptr, FILE *f)
+{
+ struct talloc_chunk *c, *tc;
+
+ if (ptr == NULL) {
+ ptr = null_context;
+ }
+ if (ptr == NULL) return;
+
+ fprintf(f,"talloc report on '%s' (total %lu bytes in %lu blocks)\n",
+ talloc_get_name(ptr),
+ (unsigned long)talloc_total_size(ptr),
+ (unsigned long)talloc_total_blocks(ptr));
+
+ tc = talloc_chunk_from_ptr(ptr);
+
+ for (c=tc->child;c;c=c->next) {
+ fprintf(f, "\t%-30s contains %6lu bytes in %3lu blocks\n",
+ talloc_get_name(c+1),
+ (unsigned long)talloc_total_size(c+1),
+ (unsigned long)talloc_total_blocks(c+1));
+ }
+
+}
+
+/*
+ report on any memory hanging off the null context
+*/
+static void talloc_report_null(void)
+{
+ if (talloc_total_size(null_context) != 0) {
+ talloc_report(null_context, stderr);
+ }
+}
+
+/*
+ report on any memory hanging off the null context
+*/
+static void talloc_report_null_full(void)
+{
+ if (talloc_total_size(null_context) != 0) {
+ talloc_report_full(null_context, stderr);
+ }
+}
+
+/*
+ enable leak reporting on exit
+*/
+void talloc_enable_leak_report(void)
+{
+ null_context = talloc_named_const(NULL, 0, "null_context");
+ atexit(talloc_report_null);
+}
+
+/*
+ enable full leak reporting on exit
+*/
+void talloc_enable_leak_report_full(void)
+{
+ null_context = talloc_named_const(NULL, 0, "null_context");
+ atexit(talloc_report_null_full);
+}
+
+/*
+ talloc and zero memory.
+*/
+void *_talloc_zero(const void *ctx, size_t size, const char *name)
+{
+ void *p = talloc_named_const(ctx, size, name);
+
+ if (p) {
+ memset(p, '\0', size);
+ }
+
+ return p;
+}
+
+
+/*
+ memdup with a talloc.
+*/
+void *_talloc_memdup(const void *t, const void *p, size_t size, const char *name)
+{
+ void *newp = talloc_named_const(t, size, name);
+
+ if (newp) {
+ memcpy(newp, p, size);
+ }
+
+ return newp;
+}
+
+/*
+ strdup with a talloc
+*/
+char *talloc_strdup(const void *t, const char *p)
+{
+ char *ret;
+ if (!p) {
+ return NULL;
+ }
+ ret = talloc_memdup(t, p, strlen(p) + 1);
+ if (ret) {
+ talloc_set_name_const(ret, ret);
+ }
+ return ret;
+}
+
+/*
+ strndup with a talloc
+*/
+char *talloc_strndup(const void *t, const char *p, size_t n)
+{
+ size_t len;
+ char *ret;
+
+ for (len=0; p[len] && len<n; len++) ;
+
+ ret = talloc(t, len + 1);
+ if (!ret) { return NULL; }
+ memcpy(ret, p, len);
+ ret[len] = 0;
+ talloc_set_name_const(ret, ret);
+ return ret;
+}
+
+#ifndef VA_COPY
+#ifdef HAVE_VA_COPY
+#define VA_COPY(dest, src) __va_copy(dest, src)
+#else
+#define VA_COPY(dest, src) (dest) = (src)
+#endif
+#endif
+
+char *talloc_vasprintf(const void *t, const char *fmt, va_list ap)
+{
+ int len;
+ char *ret;
+ va_list ap2;
+
+ VA_COPY(ap2, ap);
+
+ len = vsnprintf(NULL, 0, fmt, ap2);
+
+ ret = talloc(t, len+1);
+ if (ret) {
+ VA_COPY(ap2, ap);
+ vsnprintf(ret, len+1, fmt, ap2);
+ talloc_set_name_const(ret, ret);
+ }
+
+ return ret;
+}
+
+
+/*
+ Perform string formatting, and return a pointer to newly allocated
+ memory holding the result, inside a memory pool.
+ */
+char *talloc_asprintf(const void *t, const char *fmt, ...)
+{
+ va_list ap;
+ char *ret;
+
+ va_start(ap, fmt);
+ ret = talloc_vasprintf(t, fmt, ap);
+ va_end(ap);
+ return ret;
+}
+
+
+/**
+ * Realloc @p s to append the formatted result of @p fmt and @p ap,
+ * and return @p s, which may have moved. Good for gradually
+ * accumulating output into a string buffer.
+ **/
+
+static char *talloc_vasprintf_append(char *s, const char *fmt, va_list ap) PRINTF_ATTRIBUTE(2,0);
+
+static char *talloc_vasprintf_append(char *s, const char *fmt, va_list ap)
+{
+ int len, s_len;
+ va_list ap2;
+
+ VA_COPY(ap2, ap);
+
+ if (s) {
+ s_len = strlen(s);
+ } else {
+ s_len = 0;
+ }
+ len = vsnprintf(NULL, 0, fmt, ap2);
+
+ s = talloc_realloc(NULL, s, s_len + len+1);
+ if (!s) return NULL;
+
+ VA_COPY(ap2, ap);
+
+ vsnprintf(s+s_len, len+1, fmt, ap2);
+ talloc_set_name_const(s, s);
+
+ return s;
+}
+
+/*
+ Realloc @p s to append the formatted result of @p fmt and return @p
+ s, which may have moved. Good for gradually accumulating output
+ into a string buffer.
+ */
+char *talloc_asprintf_append(char *s, const char *fmt, ...)
+{
+ va_list ap;
+
+ va_start(ap, fmt);
+ s = talloc_vasprintf_append(s, fmt, ap);
+ va_end(ap);
+ return s;
+}
+
+/*
+ alloc an array, checking for integer overflow in the array size
+*/
+void *talloc_array(const void *ctx, size_t el_size, unsigned count, const char *name)
+{
+ if (count >= MAX_TALLOC_SIZE/el_size) {
+ return NULL;
+ }
+ return talloc_named_const(ctx, el_size * count, name);
+}
+
+/*
+ alloc an zero array, checking for integer overflow in the array size
+*/
+void *talloc_zero_array(const void *ctx, size_t el_size, unsigned count, const char *name)
+{
+ if (count >= MAX_TALLOC_SIZE/el_size) {
+ return NULL;
+ }
+ return _talloc_zero(ctx, el_size * count, name);
+}
+
+
+/*
+ realloc an array, checking for integer overflow in the array size
+*/
+void *talloc_realloc_array(const void *ctx, void *ptr, size_t el_size, unsigned count, const char *name)
+{
+ if (count >= MAX_TALLOC_SIZE/el_size) {
+ return NULL;
+ }
+ ptr = talloc_realloc(ctx, ptr, el_size * count);
+ if (ptr) {
+ talloc_set_name_const(ptr, name);
+ }
+ return ptr;
+}
+
+/*
+ a function version of talloc_realloc(), so it can be passed as a function pointer
+ to libraries that want a realloc function (a realloc function encapsulates
+ all the basic capabilities of an allocation library, which is why this is useful)
+*/
+void *talloc_realloc_fn(const void *context, void *ptr, size_t size)
+{
+ return _talloc_realloc(context, ptr, size, NULL);
+}