talloc: Import 2.0.1 code.

1 files changed, 1994 insertions, 0 deletions

diff --git a/src/talloc/talloc.c b/src/talloc/talloc.c
new file mode 100644
index 00000000000..7beda4b0f58
--- /dev/null
+++ b/src/talloc/talloc.c
@@ -0,0 +1,1994 @@
+/* 
+   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
+   Copyright (C) Stefan Metzmacher 2006
+   
+     ** NOTE! The following LGPL license applies to the talloc
+     ** library. This does NOT imply that all of Samba is released
+     ** under the LGPL
+   
+   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 3 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, see <http://www.gnu.org/licenses/>.
+*/
+
+/*
+  inspired by http://swapped.cc/halloc/
+*/
+
+#include "replace.h"
+#include "talloc.h"
+
+#ifdef TALLOC_BUILD_VERSION_MAJOR
+#if (TALLOC_VERSION_MAJOR != TALLOC_BUILD_VERSION_MAJOR)
+#error "TALLOC_VERSION_MAJOR != TALLOC_BUILD_VERSION_MAJOR"
+#endif
+#endif
+
+#ifdef TALLOC_BUILD_VERSION_MINOR
+#if (TALLOC_VERSION_MINOR != TALLOC_BUILD_VERSION_MINOR)
+#error "TALLOC_VERSION_MINOR != TALLOC_BUILD_VERSION_MINOR"
+#endif
+#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_BASE 0xe814ec70
+#define TALLOC_MAGIC ( \
+	TALLOC_MAGIC_BASE + \
+	(TALLOC_VERSION_MAJOR << 12) + \
+	(TALLOC_VERSION_MINOR << 4) \
+)
+
+#define TALLOC_FLAG_FREE 0x01
+#define TALLOC_FLAG_LOOP 0x02
+#define TALLOC_FLAG_POOL 0x04		/* This is a talloc pool */
+#define TALLOC_FLAG_POOLMEM 0x08	/* This is allocated in a pool */
+#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
+
+/* these macros gain us a few percent of speed on gcc */
+#if (__GNUC__ >= 3)
+/* the strange !! is to ensure that __builtin_expect() takes either 0 or 1
+   as its first argument */
+#ifndef likely
+#define likely(x)   __builtin_expect(!!(x), 1)
+#endif
+#ifndef unlikely
+#define unlikely(x) __builtin_expect(!!(x), 0)
+#endif
+#else
+#ifndef likely
+#define likely(x) (x)
+#endif
+#ifndef unlikely
+#define unlikely(x) (x)
+#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 void *null_context;
+static void *autofree_context;
+
+struct talloc_reference_handle {
+	struct talloc_reference_handle *next, *prev;
+	void *ptr;
+	const char *location;
+};
+
+typedef int (*talloc_destructor_t)(void *);
+
+struct talloc_chunk {
+	struct talloc_chunk *next, *prev;
+	struct talloc_chunk *parent, *child;
+	struct talloc_reference_handle *refs;
+	talloc_destructor_t destructor;
+	const char *name;
+	size_t size;
+	unsigned flags;
+
+	/*
+	 * "pool" has dual use:
+	 *
+	 * For the talloc pool itself (i.e. TALLOC_FLAG_POOL is set), "pool"
+	 * marks the end of the currently allocated area.
+	 *
+	 * For members of the pool (i.e. TALLOC_FLAG_POOLMEM is set), "pool"
+	 * is a pointer to the struct talloc_chunk of the pool that it was
+	 * allocated from. This way children can quickly find the pool to chew
+	 * from.
+	 */
+	void *pool;
+};
+
+/* 16 byte alignment seems to keep everyone happy */
+#define TC_HDR_SIZE ((sizeof(struct talloc_chunk)+15)&~15)
+#define TC_PTR_FROM_CHUNK(tc) ((void *)(TC_HDR_SIZE + (char*)tc))
+
+int talloc_version_major(void)
+{
+	return TALLOC_VERSION_MAJOR;
+}
+
+int talloc_version_minor(void)
+{
+	return TALLOC_VERSION_MINOR;
+}
+
+static void (*talloc_log_fn)(const char *message);
+
+void talloc_set_log_fn(void (*log_fn)(const char *message))
+{
+	talloc_log_fn = log_fn;
+}
+
+static void talloc_log(const char *fmt, ...) PRINTF_ATTRIBUTE(1,2);
+static void talloc_log(const char *fmt, ...)
+{
+	va_list ap;
+	char *message;
+
+	if (!talloc_log_fn) {
+		return;
+	}
+
+	va_start(ap, fmt);
+	message = talloc_vasprintf(NULL, fmt, ap);
+	va_end(ap);
+
+	talloc_log_fn(message);
+	talloc_free(message);
+}
+
+static void talloc_log_stderr(const char *message)
+{
+	fprintf(stderr, "%s", message);
+}
+
+void talloc_set_log_stderr(void)
+{
+	talloc_set_log_fn(talloc_log_stderr);
+}
+
+static void (*talloc_abort_fn)(const char *reason);
+
+void talloc_set_abort_fn(void (*abort_fn)(const char *reason))
+{
+	talloc_abort_fn = abort_fn;
+}
+
+static void talloc_abort(const char *reason)
+{
+	talloc_log("%s\n", reason);
+
+	if (!talloc_abort_fn) {
+		TALLOC_ABORT(reason);
+	}
+
+	talloc_abort_fn(reason);
+}
+
+static void talloc_abort_magic(unsigned magic)
+{
+	unsigned striped = magic - TALLOC_MAGIC_BASE;
+	unsigned major = (striped & 0xFFFFF000) >> 12;
+	unsigned minor = (striped & 0x00000FF0) >> 4;
+	talloc_log("Bad talloc magic[0x%08X/%u/%u] expected[0x%08X/%u/%u]\n",
+		   magic, major, minor,
+		   TALLOC_MAGIC, TALLOC_VERSION_MAJOR, TALLOC_VERSION_MINOR);
+	talloc_abort("Bad talloc magic value - wrong talloc version used/mixed");
+}
+
+static void talloc_abort_double_free(void)
+{
+	talloc_abort("Bad talloc magic value - double free");
+}
+
+static void talloc_abort_unknown_value(void)
+{
+	talloc_abort("Bad talloc magic value - unknown value");
+}
+
+/* panic if we get a bad magic value */
+static inline struct talloc_chunk *talloc_chunk_from_ptr(const void *ptr)
+{
+	const char *pp = (const char *)ptr;
+	struct talloc_chunk *tc = discard_const_p(struct talloc_chunk, pp - TC_HDR_SIZE);
+	if (unlikely((tc->flags & (TALLOC_FLAG_FREE | ~0xF)) != TALLOC_MAGIC)) { 
+		if ((tc->flags & (~0xFFF)) == TALLOC_MAGIC_BASE) {
+			talloc_abort_magic(tc->flags & (~0xF));
+			return NULL;
+		}
+
+		if (tc->flags & TALLOC_FLAG_FREE) {
+			talloc_log("talloc: double free error - first free may be at %s\n", tc->name);
+			talloc_abort_double_free();
+			return NULL;
+		} else {
+			talloc_abort_unknown_value();
+			return NULL;
+		}
+	}
+	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 inline struct talloc_chunk *talloc_parent_chunk(const void *ptr)
+{
+	struct talloc_chunk *tc;
+
+	if (unlikely(ptr == NULL)) {
+		return NULL;
+	}
+
+	tc = talloc_chunk_from_ptr(ptr);
+	while (tc->prev) tc=tc->prev;
+
+	return tc->parent;
+}
+
+void *talloc_parent(const void *ptr)
+{
+	struct talloc_chunk *tc = talloc_parent_chunk(ptr);
+	return tc? TC_PTR_FROM_CHUNK(tc) : NULL;
+}
+
+/*
+  find parents name
+*/
+const char *talloc_parent_name(const void *ptr)
+{
+	struct talloc_chunk *tc = talloc_parent_chunk(ptr);
+	return tc? tc->name : NULL;
+}
+
+/*
+  A pool carries an in-pool object count count in the first 16 bytes.
+  bytes. This is done to support talloc_steal() to a parent outside of the
+  pool. The count includes the pool itself, so a talloc_free() on a pool will
+  only destroy the pool if the count has dropped to zero. A talloc_free() of a
+  pool member will reduce the count, and eventually also call free(3) on the
+  pool memory.
+
+  The object count is not put into "struct talloc_chunk" because it is only
+  relevant for talloc pools and the alignment to 16 bytes would increase the
+  memory footprint of each talloc chunk by those 16 bytes.
+*/
+
+#define TALLOC_POOL_HDR_SIZE 16
+
+static unsigned int *talloc_pool_objectcount(struct talloc_chunk *tc)
+{
+	return (unsigned int *)((char *)tc + sizeof(struct talloc_chunk));
+}
+
+/*
+  Allocate from a pool
+*/
+
+static struct talloc_chunk *talloc_alloc_pool(struct talloc_chunk *parent,
+					      size_t size)
+{
+	struct talloc_chunk *pool_ctx = NULL;
+	size_t space_left;
+	struct talloc_chunk *result;
+	size_t chunk_size;
+
+	if (parent == NULL) {
+		return NULL;
+	}
+
+	if (parent->flags & TALLOC_FLAG_POOL) {
+		pool_ctx = parent;
+	}
+	else if (parent->flags & TALLOC_FLAG_POOLMEM) {
+		pool_ctx = (struct talloc_chunk *)parent->pool;
+	}
+
+	if (pool_ctx == NULL) {
+		return NULL;
+	}
+
+	space_left = ((char *)pool_ctx + TC_HDR_SIZE + pool_ctx->size)
+		- ((char *)pool_ctx->pool);
+
+	/*
+	 * Align size to 16 bytes
+	 */
+	chunk_size = ((size + 15) & ~15);
+
+	if (space_left < chunk_size) {
+		return NULL;
+	}
+
+	result = (struct talloc_chunk *)pool_ctx->pool;
+
+#if defined(DEVELOPER) && defined(VALGRIND_MAKE_MEM_UNDEFINED)
+	VALGRIND_MAKE_MEM_UNDEFINED(result, size);
+#endif
+
+	pool_ctx->pool = (void *)((char *)result + chunk_size);
+
+	result->flags = TALLOC_MAGIC | TALLOC_FLAG_POOLMEM;
+	result->pool = pool_ctx;
+
+	*talloc_pool_objectcount(pool_ctx) += 1;
+
+	return result;
+}
+
+/* 
+   Allocate a bit of memory as a child of an existing pointer
+*/
+static inline void *__talloc(const void *context, size_t size)
+{
+	struct talloc_chunk *tc = NULL;
+
+	if (unlikely(context == NULL)) {
+		context = null_context;
+	}
+
+	if (unlikely(size >= MAX_TALLOC_SIZE)) {
+		return NULL;
+	}
+
+	if (context != NULL) {
+		tc = talloc_alloc_pool(talloc_chunk_from_ptr(context),
+				       TC_HDR_SIZE+size);
+	}
+
+	if (tc == NULL) {
+		tc = (struct talloc_chunk *)malloc(TC_HDR_SIZE+size);
+		if (unlikely(tc == NULL)) return NULL;
+		tc->flags = TALLOC_MAGIC;
+		tc->pool  = NULL;
+	}
+
+	tc->size = size;
+	tc->destructor = NULL;
+	tc->child = NULL;
+	tc->name = NULL;
+	tc->refs = NULL;
+
+	if (likely(context)) {
+		struct talloc_chunk *parent = talloc_chunk_from_ptr(context);
+
+		if (parent->child) {
+			parent->child->parent = NULL;
+			tc->next = parent->child;
+			tc->next->prev = tc;
+		} else {
+			tc->next = NULL;
+		}
+		tc->parent = parent;
+		tc->prev = NULL;
+		parent->child = tc;
+	} else {
+		tc->next = tc->prev = tc->parent = NULL;
+	}
+
+	return TC_PTR_FROM_CHUNK(tc);
+}
+
+/*
+ * Create a talloc pool
+ */
+
+void *talloc_pool(const void *context, size_t size)
+{
+	void *result = __talloc(context, size + TALLOC_POOL_HDR_SIZE);
+	struct talloc_chunk *tc;
+
+	if (unlikely(result == NULL)) {
+		return NULL;
+	}
+
+	tc = talloc_chunk_from_ptr(result);
+
+	tc->flags |= TALLOC_FLAG_POOL;
+	tc->pool = (char *)result + TALLOC_POOL_HDR_SIZE;
+
+	*talloc_pool_objectcount(tc) = 1;
+
+#if defined(DEVELOPER) && defined(VALGRIND_MAKE_MEM_NOACCESS)
+	VALGRIND_MAKE_MEM_NOACCESS(tc->pool, size);
+#endif
+
+	return result;
+}
+
+/*
+  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. 
+*/
+int talloc_increase_ref_count(const void *ptr)
+{
+	if (unlikely(!talloc_reference(null_context, ptr))) {
+		return -1;
+	}
+	return 0;
+}
+
+/*
+  helper for talloc_reference()
+
+  this is referenced by a function pointer and should not be inline
+*/
+static int talloc_reference_destructor(struct talloc_reference_handle *handle)
+{
+	struct talloc_chunk *ptr_tc = talloc_chunk_from_ptr(handle->ptr);
+	_TLIST_REMOVE(ptr_tc->refs, handle);
+	return 0;
+}
+
+/*
+   more efficient way to add a name to a pointer - the name must point to a 
+   true string constant
+*/
+static inline void _talloc_set_name_const(const void *ptr, const char *name)
+{
+	struct talloc_chunk *tc = talloc_chunk_from_ptr(ptr);
+	tc->name = name;
+}
+
+/*
+  internal talloc_named_const()
+*/
+static inline void *_talloc_named_const(const void *context, size_t size, const char *name)
+{
+	void *ptr;
+
+	ptr = __talloc(context, size);
+	if (unlikely(ptr == NULL)) {
+		return NULL;
+	}
+
+	_talloc_set_name_const(ptr, name);
+
+	return ptr;
+}
+
+/*
+  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_loc(const void *context, const void *ptr, const char *location)
+{
+	struct talloc_chunk *tc;
+	struct talloc_reference_handle *handle;
+	if (unlikely(ptr == NULL)) return NULL;
+
+	tc = talloc_chunk_from_ptr(ptr);
+	handle = (struct talloc_reference_handle *)_talloc_named_const(context,
+						   sizeof(struct talloc_reference_handle),
+						   TALLOC_MAGIC_REFERENCE);
+	if (unlikely(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);
+	handle->location = location;
+	_TLIST_ADD(tc->refs, handle);
+	return handle->ptr;
+}
+
+static void *_talloc_steal_internal(const void *new_ctx, const void *ptr);
+
+/* 
+   internal talloc_free call
+*/
+static inline int _talloc_free_internal(void *ptr, const char *location)
+{
+	struct talloc_chunk *tc;
+
+	if (unlikely(ptr == NULL)) {
+		return -1;
+	}
+
+	tc = talloc_chunk_from_ptr(ptr);
+
+	if (unlikely(tc->refs)) {
+		int is_child;
+		/* check this is a reference from a child or grantchild
+		 * back to it's parent or grantparent
+		 *
+		 * in that case we need to remove the reference and
+		 * call another instance of talloc_free() on the current
+		 * pointer.
+		 */
+		is_child = talloc_is_parent(tc->refs, ptr);
+		_talloc_free_internal(tc->refs, location);
+		if (is_child) {
+			return _talloc_free_internal(ptr, location);
+		}
+		return -1;
+	}
+
+	if (unlikely(tc->flags & TALLOC_FLAG_LOOP)) {
+		/* we have a free loop - stop looping */
+		return 0;
+	}
+
+	if (unlikely(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;
+	}
+
+	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->flags |= TALLOC_FLAG_LOOP;
+
+	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_PTR_FROM_CHUNK(tc->child);
+		const void *new_parent = null_context;
+		if (unlikely(tc->child->refs)) {
+			struct talloc_chunk *p = talloc_parent_chunk(tc->child->refs);
+			if (p) new_parent = TC_PTR_FROM_CHUNK(p);
+		}
+		if (unlikely(_talloc_free_internal(child, location) == -1)) {
+			if (new_parent == null_context) {
+				struct talloc_chunk *p = talloc_parent_chunk(ptr);
+				if (p) new_parent = TC_PTR_FROM_CHUNK(p);
+			}
+			_talloc_steal_internal(new_parent, child);
+		}
+	}
+
+	tc->flags |= TALLOC_FLAG_FREE;
+
+	/* we mark the freed memory with where we called the free
+	 * from. This means on a double free error we can report where
+	 * the first free came from 
+	 */	 
+	tc->name = location;
+
+	if (tc->flags & (TALLOC_FLAG_POOL|TALLOC_FLAG_POOLMEM)) {
+		struct talloc_chunk *pool;
+		unsigned int *pool_object_count;
+
+		pool = (tc->flags & TALLOC_FLAG_POOL)
+			? tc : (struct talloc_chunk *)tc->pool;
+
+		pool_object_count = talloc_pool_objectcount(pool);
+
+		if (*pool_object_count == 0) {
+			talloc_abort("Pool object count zero!");
+			return 0;
+		}
+
+		*pool_object_count -= 1;
+
+		if (*pool_object_count == 0) {
+			free(pool);
+		}
+	}
+	else {
+		free(tc);
+	}
+	return 0;
+}
+
+/* 
+   move a lump of memory from one talloc context to another return the
+   ptr on success, or NULL if it could not be transferred.
+   passing NULL as ptr will always return NULL with no side effects.
+*/
+static void *_talloc_steal_internal(const void *new_ctx, const void *ptr)
+{
+	struct talloc_chunk *tc, *new_tc;
+
+	if (unlikely(!ptr)) {
+		return NULL;
+	}
+
+	if (unlikely(new_ctx == NULL)) {
+		new_ctx = null_context;
+	}
+
+	tc = talloc_chunk_from_ptr(ptr);
+
+	if (unlikely(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 (unlikely(tc == new_tc || tc->parent == 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);
+}
+
+/* 
+   move a lump of memory from one talloc context to another return the
+   ptr on success, or NULL if it could not be transferred.
+   passing NULL as ptr will always return NULL with no side effects.
+*/
+void *_talloc_steal_loc(const void *new_ctx, const void *ptr, const char *location)
+{
+	struct talloc_chunk *tc;
+
+	if (unlikely(ptr == NULL)) {
+		return NULL;
+	}
+	
+	tc = talloc_chunk_from_ptr(ptr);
+	
+	if (unlikely(tc->refs != NULL) && talloc_parent(ptr) != new_ctx) {
+		struct talloc_reference_handle *h;
+
+		talloc_log("WARNING: talloc_steal with references at %s\n",
+			   location);
+
+		for (h=tc->refs; h; h=h->next) {
+			talloc_log("\treference at %s\n",
+				   h->location);
+		}
+	}
+	
+	return _talloc_steal_internal(new_ctx, ptr);
+}
+
+/* 
+   this is like a talloc_steal(), but you must supply the old
+   parent. This resolves the ambiguity in a talloc_steal() which is
+   called on a context that has more than one parent (via references)
+
+   The old parent can be either a reference or a parent
+*/
+void *talloc_reparent(const void *old_parent, const void *new_parent, const void *ptr)
+{
+	struct talloc_chunk *tc;
+	struct talloc_reference_handle *h;
+
+	if (unlikely(ptr == NULL)) {
+		return NULL;
+	}
+
+	if (old_parent == talloc_parent(ptr)) {
+		return _talloc_steal_internal(new_parent, ptr);
+	}
+
+	tc = talloc_chunk_from_ptr(ptr);
+	for (h=tc->refs;h;h=h->next) {
+		if (talloc_parent(h) == old_parent) {
+			if (_talloc_steal_internal(new_parent, h) != h) {
+				return NULL;
+			}
+			return discard_const_p(void, ptr);
+		}
+	}	
+
+	/* it wasn't a parent */
+	return NULL;
+}
+
+/*
+  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 inline int talloc_unreference(const void *context, const void *ptr)
+{
+	struct talloc_chunk *tc = talloc_chunk_from_ptr(ptr);
+	struct talloc_reference_handle *h;
+
+	if (unlikely(context == NULL)) {
+		context = null_context;
+	}
+
+	for (h=tc->refs;h;h=h->next) {
+		struct talloc_chunk *p = talloc_parent_chunk(h);
+		if (p == NULL) {
+			if (context == NULL) break;
+		} else if (TC_PTR_FROM_CHUNK(p) == context) {
+			break;
+		}
+	}
+	if (h == NULL) {
+		return -1;
+	}
+
+	return _talloc_free_internal(h, __location__);
+}
+
+/*
+  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_internal(ptr, __location__);
+	}
+
+	new_p = talloc_parent_chunk(tc_p->refs);
+	if (new_p) {
+		new_parent = TC_PTR_FROM_CHUNK(new_p);
+	} else {
+		new_parent = NULL;
+	}
+
+	if (talloc_unreference(new_parent, ptr) != 0) {
+		return -1;
+	}
+
+	_talloc_steal_internal(new_parent, ptr);
+
+	return 0;
+}
+
+/*
+  add a name to an existing pointer - va_list version
+*/
+static inline const char *talloc_set_name_v(const void *ptr, const char *fmt, va_list ap) PRINTF_ATTRIBUTE(2,0);
+
+static inline const char *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 (likely(tc->name)) {
+		_talloc_set_name_const(tc->name, ".name");
+	}
+	return tc->name;
+}
+
+/*
+  add a name to an existing pointer
+*/
+const char *talloc_set_name(const void *ptr, const char *fmt, ...)
+{
+	const char *name;
+	va_list ap;
+	va_start(ap, fmt);
+	name = talloc_set_name_v(ptr, fmt, ap);
+	va_end(ap);
+	return 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;
+	const char *name;
+
+	ptr = __talloc(context, size);
+	if (unlikely(ptr == NULL)) return NULL;
+
+	va_start(ap, fmt);
+	name = talloc_set_name_v(ptr, fmt, ap);
+	va_end(ap);
+
+	if (unlikely(name == NULL)) {
+		_talloc_free_internal(ptr, __location__);
+		return NULL;
+	}
+
+	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 (unlikely(tc->name == TALLOC_MAGIC_REFERENCE)) {
+		return ".reference";
+	}
+	if (likely(tc->name)) {
+		return tc->name;
+	}
+	return "UNNAMED";
+}
+
+
+/*
+  check if a pointer has the given name. If it does, return the pointer,
+  otherwise return NULL
+*/
+void *talloc_check_name(const void *ptr, const char *name)
+{
+	const char *pname;
+	if (unlikely(ptr == NULL)) return NULL;
+	pname = talloc_get_name(ptr);
+	if (likely(pname == name || strcmp(pname, name) == 0)) {
+		return discard_const_p(void, ptr);
+	}
+	return NULL;
+}
+
+static void talloc_abort_type_missmatch(const char *location,
+					const char *name,
+					const char *expected)
+{
+	const char *reason;
+
+	reason = talloc_asprintf(NULL,
+				 "%s: Type mismatch: name[%s] expected[%s]",
+				 location,
+				 name?name:"NULL",
+				 expected);
+	if (!reason) {
+		reason = "Type mismatch";
+	}
+
+	talloc_abort(reason);
+}
+
+void *_talloc_get_type_abort(const void *ptr, const char *name, const char *location)
+{
+	const char *pname;
+
+	if (unlikely(ptr == NULL)) {
+		talloc_abort_type_missmatch(location, NULL, name);
+		return NULL;
+	}
+
+	pname = talloc_get_name(ptr);
+	if (likely(pname == name || strcmp(pname, name) == 0)) {
+		return discard_const_p(void, ptr);
+	}
+
+	talloc_abort_type_missmatch(location, pname, name);
+	return NULL;
+}
+
+/*
+  this is for compatibility with older versions of talloc
+*/
+void *talloc_init(const char *fmt, ...)
+{
+	va_list ap;
+	void *ptr;
+	const char *name;
+
+	/*
+	 * samba3 expects talloc_report_depth_cb(NULL, ...)
+	 * reports all talloc'ed memory, so we need to enable
+	 * null_tracking
+	 */
+	talloc_enable_null_tracking();
+
+	ptr = __talloc(NULL, 0);
+	if (unlikely(ptr == NULL)) return NULL;
+
+	va_start(ap, fmt);
+	name = talloc_set_name_v(ptr, fmt, ap);
+	va_end(ap);
+
+	if (unlikely(name == NULL)) {
+		_talloc_free_internal(ptr, __location__);
+		return NULL;
+	}
+
+	return ptr;
+}
+
+/*
+  this is a replacement for the Samba3 talloc_destroy_pool functionality. It
+  should probably not be used in new code. It's in here to keep the talloc
+  code consistent across Samba 3 and 4.
+*/
+void talloc_free_children(void *ptr)
+{
+	struct talloc_chunk *tc;
+
+	if (unlikely(ptr == NULL)) {
+		return;
+	}
+
+	tc = talloc_chunk_from_ptr(ptr);
+
+	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_PTR_FROM_CHUNK(tc->child);
+		const void *new_parent = null_context;
+		if (unlikely(tc->child->refs)) {
+			struct talloc_chunk *p = talloc_parent_chunk(tc->child->refs);
+			if (p) new_parent = TC_PTR_FROM_CHUNK(p);
+		}
+		if (unlikely(talloc_free(child) == -1)) {
+			if (new_parent == null_context) {
+				struct talloc_chunk *p = talloc_parent_chunk(ptr);
+				if (p) new_parent = TC_PTR_FROM_CHUNK(p);
+			}
+			_talloc_steal_internal(new_parent, child);
+		}
+	}
+
+	if ((tc->flags & TALLOC_FLAG_POOL)
+	    && (*talloc_pool_objectcount(tc) == 1)) {
+		tc->pool = ((char *)tc + TC_HDR_SIZE + TALLOC_POOL_HDR_SIZE);
+#if defined(DEVELOPER) && defined(VALGRIND_MAKE_MEM_NOACCESS)
+		VALGRIND_MAKE_MEM_NOACCESS(
+			tc->pool, tc->size - TALLOC_POOL_HDR_SIZE);
+#endif
+	}
+}
+
+/* 
+   Allocate a bit of memory as a child of an existing pointer
+*/
+void *_talloc(const void *context, size_t size)
+{
+	return __talloc(context, size);
+}
+
+/*
+  externally callable talloc_set_name_const()
+*/
+void talloc_set_name_const(const void *ptr, const char *name)
+{
+	_talloc_set_name_const(ptr, 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(const void *context, size_t size, const char *name)
+{
+	return _talloc_named_const(context, size, name);
+}
+
+/* 
+   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, const char *location)
+{
+	struct talloc_chunk *tc;
+
+	if (unlikely(ptr == NULL)) {
+		return -1;
+	}
+	
+	tc = talloc_chunk_from_ptr(ptr);
+	
+	if (unlikely(tc->refs != NULL)) {
+		struct talloc_reference_handle *h;
+
+		talloc_log("ERROR: talloc_free with references at %s\n",
+			   location);
+
+		for (h=tc->refs; h; h=h->next) {
+			talloc_log("\treference at %s\n",
+				   h->location);
+		}
+		return -1;
+	}
+	
+	return _talloc_free_internal(ptr, location);
+}
+
+
+
+/*
+  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;
+	bool malloced = false;
+
+	/* size zero is equivalent to free() */
+	if (unlikely(size == 0)) {
+		talloc_unlink(context, ptr);
+		return NULL;
+	}
+
+	if (unlikely(size >= MAX_TALLOC_SIZE)) {
+		return NULL;
+	}
+
+	/* realloc(NULL) is equivalent 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 (unlikely(tc->refs)) {
+		return NULL;
+	}
+
+	/* don't let anybody try to realloc a talloc_pool */
+	if (unlikely(tc->flags & TALLOC_FLAG_POOL)) {
+		return NULL;
+	}
+
+	/* don't shrink if we have less than 1k to gain */
+	if ((size < tc->size) && ((tc->size - size) < 1024)) {
+		tc->size = size;
+		return ptr;
+	}
+
+	/* by resetting magic we catch users of the old memory */
+	tc->flags |= TALLOC_FLAG_FREE;
+
+#if ALWAYS_REALLOC
+	new_ptr = malloc(size + TC_HDR_SIZE);
+	if (new_ptr) {
+		memcpy(new_ptr, tc, tc->size + TC_HDR_SIZE);
+		free(tc);
+	}
+#else
+	if (tc->flags & TALLOC_FLAG_POOLMEM) {
+
+		new_ptr = talloc_alloc_pool(tc, size + TC_HDR_SIZE);
+		*talloc_pool_objectcount((struct talloc_chunk *)
+					 (tc->pool)) -= 1;
+
+		if (new_ptr == NULL) {
+			new_ptr = malloc(TC_HDR_SIZE+size);
+			malloced = true;
+		}
+
+		if (new_ptr) {
+			memcpy(new_ptr, tc, MIN(tc->size,size) + TC_HDR_SIZE);
+		}
+	}
+	else {
+		new_ptr = realloc(tc, size + TC_HDR_SIZE);
+	}
+#endif
+	if (unlikely(!new_ptr)) {	
+		tc->flags &= ~TALLOC_FLAG_FREE; 
+		return NULL; 
+	}
+
+	tc = (struct talloc_chunk *)new_ptr;
+	tc->flags &= ~TALLOC_FLAG_FREE;
+	if (malloced) {
+		tc->flags &= ~TALLOC_FLAG_POOLMEM;
+	}
+	if (tc->parent) {
+		tc->parent->child = tc;
+	}
+	if (tc->child) {
+		tc->child->parent = tc;
+	}
+
+	if (tc->prev) {
+		tc->prev->next = tc;
+	}
+	if (tc->next) {
+		tc->next->prev = tc;
+	}
+
+	tc->size = size;
+	_talloc_set_name_const(TC_PTR_FROM_CHUNK(tc), name);
+
+	return TC_PTR_FROM_CHUNK(tc);
+}
+
+/*
+  a wrapper around talloc_steal() for situations where you are moving a pointer
+  between two structures, and want the old pointer to be set to NULL
+*/
+void *_talloc_move(const void *new_ctx, const void *_pptr)
+{
+	const void **pptr = discard_const_p(const void *,_pptr);
+	void *ret = talloc_steal(new_ctx, discard_const_p(void, *pptr));
+	(*pptr) = NULL;
+	return ret;
+}
+
+/*
+  return the total size of a talloc pool (subtree)
+*/
+size_t talloc_total_size(const void *ptr)
+{
+	size_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);
+
+	if (tc->flags & TALLOC_FLAG_LOOP) {
+		return 0;
+	}
+
+	tc->flags |= TALLOC_FLAG_LOOP;
+
+	if (likely(tc->name != TALLOC_MAGIC_REFERENCE)) {
+		total = tc->size;
+	}
+	for (c=tc->child;c;c=c->next) {
+		total += talloc_total_size(TC_PTR_FROM_CHUNK(c));
+	}
+
+	tc->flags &= ~TALLOC_FLAG_LOOP;
+
+	return total;
+}
+
+/*
+  return the total number of blocks in a talloc pool (subtree)
+*/
+size_t talloc_total_blocks(const void *ptr)
+{
+	size_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);
+
+	if (tc->flags & TALLOC_FLAG_LOOP) {
+		return 0;
+	}
+
+	tc->flags |= TALLOC_FLAG_LOOP;
+
+	total++;
+	for (c=tc->child;c;c=c->next) {
+		total += talloc_total_blocks(TC_PTR_FROM_CHUNK(c));
+	}
+
+	tc->flags &= ~TALLOC_FLAG_LOOP;
+
+	return total;
+}
+
+/*
+  return the number of external references to a pointer
+*/
+size_t talloc_reference_count(const void *ptr)
+{
+	struct talloc_chunk *tc = talloc_chunk_from_ptr(ptr);
+	struct talloc_reference_handle *h;
+	size_t 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
+*/
+void talloc_report_depth_cb(const void *ptr, int depth, int max_depth,
+			    void (*callback)(const void *ptr,
+			  		     int depth, int max_depth,
+					     int is_ref,
+					     void *private_data),
+			    void *private_data)
+{
+	struct talloc_chunk *c, *tc;
+
+	if (ptr == NULL) {
+		ptr = null_context;
+	}
+	if (ptr == NULL) return;
+
+	tc = talloc_chunk_from_ptr(ptr);
+
+	if (tc->flags & TALLOC_FLAG_LOOP) {
+		return;
+	}
+
+	callback(ptr, depth, max_depth, 0, private_data);
+
+	if (max_depth >= 0 && depth >= max_depth) {
+		return;
+	}
+
+	tc->flags |= TALLOC_FLAG_LOOP;
+	for (c=tc->child;c;c=c->next) {
+		if (c->name == TALLOC_MAGIC_REFERENCE) {
+			struct talloc_reference_handle *h = (struct talloc_reference_handle *)TC_PTR_FROM_CHUNK(c);
+			callback(h->ptr, depth + 1, max_depth, 1, private_data);
+		} else {
+			talloc_report_depth_cb(TC_PTR_FROM_CHUNK(c), depth + 1, max_depth, callback, private_data);
+		}
+	}
+	tc->flags &= ~TALLOC_FLAG_LOOP;
+}
+
+static void talloc_report_depth_FILE_helper(const void *ptr, int depth, int max_depth, int is_ref, void *_f)
+{
+	const char *name = talloc_get_name(ptr);
+	FILE *f = (FILE *)_f;
+
+	if (is_ref) {
+		fprintf(f, "%*sreference to: %s\n", depth*4, "", name);
+		return;
+	}
+
+	if (depth == 0) {
+		fprintf(f,"%stalloc report on '%s' (total %6lu bytes in %3lu blocks)\n", 
+			(max_depth < 0 ? "full " :""), name,
+			(unsigned long)talloc_total_size(ptr),
+			(unsigned long)talloc_total_blocks(ptr));
+		return;
+	}
+
+	fprintf(f, "%*s%-30s contains %6lu bytes in %3lu blocks (ref %d) %p\n", 
+		depth*4, "",
+		name,
+		(unsigned long)talloc_total_size(ptr),
+		(unsigned long)talloc_total_blocks(ptr),
+		(int)talloc_reference_count(ptr), ptr);
+
+#if 0
+	fprintf(f, "content: ");
+	if (talloc_total_size(ptr)) {
+		int tot = talloc_total_size(ptr);
+		int i;
+
+		for (i = 0; i < tot; i++) {
+			if ((((char *)ptr)[i] > 31) && (((char *)ptr)[i] < 126)) {
+				fprintf(f, "%c", ((char *)ptr)[i]);
+			} else {
+				fprintf(f, "~%02x", ((char *)ptr)[i]);
+			}
+		}
+	}
+	fprintf(f, "\n");
+#endif
+}
+
+/*
+  report on memory usage by all children of a pointer, giving a full tree view
+*/
+void talloc_report_depth_file(const void *ptr, int depth, int max_depth, FILE *f)
+{
+	if (f) {
+		talloc_report_depth_cb(ptr, depth, max_depth, talloc_report_depth_FILE_helper, f);
+		fflush(f);
+	}
+}
+
+/*
+  report on memory usage by all children of a pointer, giving a full tree view
+*/
+void talloc_report_full(const void *ptr, FILE *f)
+{
+	talloc_report_depth_file(ptr, 0, -1, f);
+}
+
+/*
+  report on memory usage by all children of a pointer
+*/
+void talloc_report(const void *ptr, FILE *f)
+{
+	talloc_report_depth_file(ptr, 0, 1, f);
+}
+
+/*
+  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 tracking of the NULL context
+*/
+void talloc_enable_null_tracking(void)
+{
+	if (null_context == NULL) {
+		null_context = _talloc_named_const(NULL, 0, "null_context");
+		if (autofree_context != NULL) {
+			talloc_reparent(NULL, null_context, autofree_context);
+		}
+	}
+}
+
+/*
+  enable tracking of the NULL context, not moving the autofree context
+  into the NULL context. This is needed for the talloc testsuite
+*/
+void talloc_enable_null_tracking_no_autofree(void)
+{
+	if (null_context == NULL) {
+		null_context = _talloc_named_const(NULL, 0, "null_context");
+	}
+}
+
+/*
+  disable tracking of the NULL context
+*/
+void talloc_disable_null_tracking(void)
+{
+	if (null_context != NULL) {
+		/* we have to move any children onto the real NULL
+		   context */
+		struct talloc_chunk *tc, *tc2;
+		tc = talloc_chunk_from_ptr(null_context);
+		for (tc2 = tc->child; tc2; tc2=tc2->next) {
+			if (tc2->parent == tc) tc2->parent = NULL;
+			if (tc2->prev == tc) tc2->prev = NULL;
+		}
+		for (tc2 = tc->next; tc2; tc2=tc2->next) {
+			if (tc2->parent == tc) tc2->parent = NULL;
+			if (tc2->prev == tc) tc2->prev = NULL;
+		}
+		tc->child = NULL;
+		tc->next = NULL;
+	}
+	talloc_free(null_context);
+	null_context = NULL;
+}
+
+/*
+  enable leak reporting on exit
+*/
+void talloc_enable_leak_report(void)
+{
+	talloc_enable_null_tracking();
+	atexit(talloc_report_null);
+}
+
+/*
+  enable full leak reporting on exit
+*/
+void talloc_enable_leak_report_full(void)
+{
+	talloc_enable_null_tracking();
+	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 (likely(newp)) {
+		memcpy(newp, p, size);
+	}
+
+	return newp;
+}
+
+static inline char *__talloc_strlendup(const void *t, const char *p, size_t len)
+{
+	char *ret;
+
+	ret = (char *)__talloc(t, len + 1);
+	if (unlikely(!ret)) return NULL;
+
+	memcpy(ret, p, len);
+	ret[len] = 0;
+
+	_talloc_set_name_const(ret, ret);
+	return ret;
+}
+
+/*
+  strdup with a talloc
+*/
+char *talloc_strdup(const void *t, const char *p)
+{
+	if (unlikely(!p)) return NULL;
+	return __talloc_strlendup(t, p, strlen(p));
+}
+
+/*
+  strndup with a talloc
+*/
+char *talloc_strndup(const void *t, const char *p, size_t n)
+{
+	if (unlikely(!p)) return NULL;
+	return __talloc_strlendup(t, p, strnlen(p, n));
+}
+
+static inline char *__talloc_strlendup_append(char *s, size_t slen,
+					      const char *a, size_t alen)
+{
+	char *ret;
+
+	ret = talloc_realloc(NULL, s, char, slen + alen + 1);
+	if (unlikely(!ret)) return NULL;
+
+	/* append the string and the trailing \0 */
+	memcpy(&ret[slen], a, alen);
+	ret[slen+alen] = 0;
+
+	_talloc_set_name_const(ret, ret);
+	return ret;
+}
+
+/*
+ * Appends at the end of the string.
+ */
+char *talloc_strdup_append(char *s, const char *a)
+{
+	if (unlikely(!s)) {
+		return talloc_strdup(NULL, a);
+	}
+
+	if (unlikely(!a)) {
+		return s;
+	}
+
+	return __talloc_strlendup_append(s, strlen(s), a, strlen(a));
+}
+
+/*
+ * Appends at the end of the talloc'ed buffer,
+ * not the end of the string.
+ */
+char *talloc_strdup_append_buffer(char *s, const char *a)
+{
+	size_t slen;
+
+	if (unlikely(!s)) {
+		return talloc_strdup(NULL, a);
+	}
+
+	if (unlikely(!a)) {
+		return s;
+	}
+
+	slen = talloc_get_size(s);
+	if (likely(slen > 0)) {
+		slen--;
+	}
+
+	return __talloc_strlendup_append(s, slen, a, strlen(a));
+}
+
+/*
+ * Appends at the end of the string.
+ */
+char *talloc_strndup_append(char *s, const char *a, size_t n)
+{
+	if (unlikely(!s)) {
+		return talloc_strdup(NULL, a);
+	}
+
+	if (unlikely(!a)) {
+		return s;
+	}
+
+	return __talloc_strlendup_append(s, strlen(s), a, strnlen(a, n));
+}
+
+/*
+ * Appends at the end of the talloc'ed buffer,
+ * not the end of the string.
+ */
+char *talloc_strndup_append_buffer(char *s, const char *a, size_t n)
+{
+	size_t slen;
+
+	if (unlikely(!s)) {
+		return talloc_strdup(NULL, a);
+	}
+
+	if (unlikely(!a)) {
+		return s;
+	}
+
+	slen = talloc_get_size(s);
+	if (likely(slen > 0)) {
+		slen--;
+	}
+
+	return __talloc_strlendup_append(s, slen, a, strnlen(a, n));
+}
+
+#ifndef HAVE_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;
+	char c;
+
+	/* this call looks strange, but it makes it work on older solaris boxes */
+	va_copy(ap2, ap);
+	len = vsnprintf(&c, 1, fmt, ap2);
+	va_end(ap2);
+	if (unlikely(len < 0)) {
+		return NULL;
+	}
+
+	ret = (char *)__talloc(t, len+1);
+	if (unlikely(!ret)) return NULL;
+
+	va_copy(ap2, ap);
+	vsnprintf(ret, len+1, fmt, ap2);
+	va_end(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;
+}
+
+static inline char *__talloc_vaslenprintf_append(char *s, size_t slen,
+						 const char *fmt, va_list ap)
+						 PRINTF_ATTRIBUTE(3,0);
+
+static inline char *__talloc_vaslenprintf_append(char *s, size_t slen,
+						 const char *fmt, va_list ap)
+{
+	ssize_t alen;
+	va_list ap2;
+	char c;
+
+	va_copy(ap2, ap);
+	alen = vsnprintf(&c, 1, fmt, ap2);
+	va_end(ap2);
+
+	if (alen <= 0) {
+		/* Either the vsnprintf failed or the format resulted in
+		 * no characters being formatted. In the former case, we
+		 * ought to return NULL, in the latter we ought to return
+		 * the original string. Most current callers of this
+		 * function expect it to never return NULL.
+		 */
+		return s;
+	}
+
+	s = talloc_realloc(NULL, s, char, slen + alen + 1);
+	if (!s) return NULL;
+
+	va_copy(ap2, ap);
+	vsnprintf(s + slen, alen + 1, fmt, ap2);
+	va_end(ap2);
+
+	_talloc_set_name_const(s, s);
+	return s;
+}
+
+/**
+ * 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. Appends at the end
+ * of the string.
+ **/
+char *talloc_vasprintf_append(char *s, const char *fmt, va_list ap)
+{
+	if (unlikely(!s)) {
+		return talloc_vasprintf(NULL, fmt, ap);
+	}
+
+	return __talloc_vaslenprintf_append(s, strlen(s), fmt, ap);
+}
+
+/**
+ * Realloc @p s to append the formatted result of @p fmt and @p ap,
+ * and return @p s, which may have moved. Always appends at the
+ * end of the talloc'ed buffer, not the end of the string.
+ **/
+char *talloc_vasprintf_append_buffer(char *s, const char *fmt, va_list ap)
+{
+	size_t slen;
+
+	if (unlikely(!s)) {
+		return talloc_vasprintf(NULL, fmt, ap);
+	}
+
+	slen = talloc_get_size(s);
+	if (likely(slen > 0)) {
+		slen--;
+	}
+
+	return __talloc_vaslenprintf_append(s, slen, fmt, ap);
+}
+
+/*
+  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;
+}
+
+/*
+  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 buffer.
+ */
+char *talloc_asprintf_append_buffer(char *s, const char *fmt, ...)
+{
+	va_list ap;
+
+	va_start(ap, fmt);
+	s = talloc_vasprintf_append_buffer(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;
+	}
+	return _talloc_realloc(ctx, ptr, el_size * count, name);
+}
+
+/*
+  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);
+}
+
+
+static int talloc_autofree_destructor(void *ptr)
+{
+	autofree_context = NULL;
+	return 0;
+}
+
+static void talloc_autofree(void)
+{
+	talloc_free(autofree_context);
+}
+
+/*
+  return a context which will be auto-freed on exit
+  this is useful for reducing the noise in leak reports
+*/
+void *talloc_autofree_context(void)
+{
+	if (autofree_context == NULL) {
+		autofree_context = _talloc_named_const(NULL, 0, "autofree_context");
+		talloc_set_destructor(autofree_context, talloc_autofree_destructor);
+		atexit(talloc_autofree);
+	}
+	return autofree_context;
+}
+
+size_t talloc_get_size(const void *context)
+{
+	struct talloc_chunk *tc;
+
+	if (context == NULL) {
+		context = null_context;
+	}
+	if (context == NULL) {
+		return 0;
+	}
+
+	tc = talloc_chunk_from_ptr(context);
+
+	return tc->size;
+}
+
+/*
+  find a parent of this context that has the given name, if any
+*/
+void *talloc_find_parent_byname(const void *context, const char *name)
+{
+	struct talloc_chunk *tc;
+
+	if (context == NULL) {
+		return NULL;
+	}
+
+	tc = talloc_chunk_from_ptr(context);
+	while (tc) {
+		if (tc->name && strcmp(tc->name, name) == 0) {
+			return TC_PTR_FROM_CHUNK(tc);
+		}
+		while (tc && tc->prev) tc = tc->prev;
+		if (tc) {
+			tc = tc->parent;
+		}
+	}
+	return NULL;
+}
+
+/*
+  show the parentage of a context
+*/
+void talloc_show_parents(const void *context, FILE *file)
+{
+	struct talloc_chunk *tc;
+
+	if (context == NULL) {
+		fprintf(file, "talloc no parents for NULL\n");
+		return;
+	}
+
+	tc = talloc_chunk_from_ptr(context);
+	fprintf(file, "talloc parents of '%s'\n", talloc_get_name(context));
+	while (tc) {
+		fprintf(file, "\t'%s'\n", talloc_get_name(TC_PTR_FROM_CHUNK(tc)));
+		while (tc && tc->prev) tc = tc->prev;
+		if (tc) {
+			tc = tc->parent;
+		}
+	}
+	fflush(file);
+}
+
+/*
+  return 1 if ptr is a parent of context
+*/
+int talloc_is_parent(const void *context, const void *ptr)
+{
+	struct talloc_chunk *tc;
+
+	if (context == NULL) {
+		return 0;
+	}
+
+	tc = talloc_chunk_from_ptr(context);
+	while (tc) {
+		if (TC_PTR_FROM_CHUNK(tc) == ptr) return 1;
+		while (tc && tc->prev) tc = tc->prev;
+		if (tc) {
+			tc = tc->parent;
+		}
+	}
+	return 0;
+}