2 Samba Unix SMB/CIFS implementation.
4 Samba trivial allocation library - new interface
6 NOTE: Please read talloc_guide.txt for full documentation
8 Copyright (C) Andrew Tridgell 2004
9 Copyright (C) Stefan Metzmacher 2006
11 ** NOTE! The following LGPL license applies to the talloc
12 ** library. This does NOT imply that all of Samba is released
15 This library is free software; you can redistribute it and/or
16 modify it under the terms of the GNU Lesser General Public
17 License as published by the Free Software Foundation; either
18 version 3 of the License, or (at your option) any later version.
20 This library is distributed in the hope that it will be useful,
21 but WITHOUT ANY WARRANTY; without even the implied warranty of
22 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
23 Lesser General Public License for more details.
25 You should have received a copy of the GNU Lesser General Public
26 License along with this library; if not, see <http://www.gnu.org/licenses/>.
30 inspired by http://swapped.cc/halloc/
35 #if (SAMBA_VERSION_MAJOR<4)
37 /* This is to circumvent SAMBA3's paranoid malloc checker. Here in this file
38 * we trust ourselves... */
45 #define _TALLOC_SAMBA3
46 #endif /* (SAMBA_VERSION_MAJOR<4) */
47 #endif /* _SAMBA_BUILD_ */
49 #ifndef _TALLOC_SAMBA3
52 #endif /* not _TALLOC_SAMBA3 */
54 /* use this to force every realloc to change the pointer, to stress test
55 code that might not cope */
56 #define ALWAYS_REALLOC 0
59 #define MAX_TALLOC_SIZE 0x10000000
60 #define TALLOC_MAGIC_V1 0xe814ec70
61 #define TALLOC_MAGIC_V2 0xe814ec80
62 #define TALLOC_MAGIC TALLOC_MAGIC_V2
63 #define TALLOC_FLAG_FREE 0x01
64 #define TALLOC_FLAG_LOOP 0x02
65 #define TALLOC_FLAG_POOL 0x04 /* This is a talloc pool */
66 #define TALLOC_FLAG_POOLMEM 0x08 /* This is allocated in a pool */
67 #define TALLOC_MAGIC_REFERENCE ((const char *)1)
69 /* by default we abort when given a bad pointer (such as when talloc_free() is called
70 on a pointer that came from malloc() */
72 #define TALLOC_ABORT(reason) abort()
75 #ifndef discard_const_p
76 #if defined(__intptr_t_defined) || defined(HAVE_INTPTR_T)
77 # define discard_const_p(type, ptr) ((type *)((intptr_t)(ptr)))
79 # define discard_const_p(type, ptr) ((type *)(ptr))
83 /* these macros gain us a few percent of speed on gcc */
85 /* the strange !! is to ensure that __builtin_expect() takes either 0 or 1
86 as its first argument */
88 #define likely(x) __builtin_expect(!!(x), 1)
91 #define unlikely(x) __builtin_expect(!!(x), 0)
98 #define unlikely(x) (x)
102 /* this null_context is only used if talloc_enable_leak_report() or
103 talloc_enable_leak_report_full() is called, otherwise it remains
106 static void *null_context;
107 static void *autofree_context;
109 struct talloc_reference_handle {
110 struct talloc_reference_handle *next, *prev;
112 const char *location;
115 typedef int (*talloc_destructor_t)(void *);
117 struct talloc_chunk {
118 struct talloc_chunk *next, *prev;
119 struct talloc_chunk *parent, *child;
120 struct talloc_reference_handle *refs;
121 talloc_destructor_t destructor;
127 * "pool" has dual use:
129 * For the talloc pool itself (i.e. TALLOC_FLAG_POOL is set), "pool"
130 * marks the end of the currently allocated area.
132 * For members of the pool (i.e. TALLOC_FLAG_POOLMEM is set), "pool"
133 * is a pointer to the struct talloc_chunk of the pool that it was
134 * allocated from. This way children can quickly find the pool to chew
140 /* 16 byte alignment seems to keep everyone happy */
141 #define TC_HDR_SIZE ((sizeof(struct talloc_chunk)+15)&~15)
142 #define TC_PTR_FROM_CHUNK(tc) ((void *)(TC_HDR_SIZE + (char*)tc))
144 static void (*talloc_abort_fn)(const char *reason);
146 void talloc_set_abort_fn(void (*abort_fn)(const char *reason))
148 talloc_abort_fn = abort_fn;
151 static void talloc_abort(const char *reason)
153 if (!talloc_abort_fn) {
154 TALLOC_ABORT(reason);
157 talloc_abort_fn(reason);
160 static void talloc_abort_magic_v1(void)
162 talloc_abort("Bad talloc magic value - old magic v1 used");
165 static void talloc_abort_double_free(void)
167 talloc_abort("Bad talloc magic value - double free");
170 static void talloc_abort_unknown_value(void)
172 talloc_abort("Bad talloc magic value - unknown value");
175 /* panic if we get a bad magic value */
176 static inline struct talloc_chunk *talloc_chunk_from_ptr(const void *ptr)
178 const char *pp = (const char *)ptr;
179 struct talloc_chunk *tc = discard_const_p(struct talloc_chunk, pp - TC_HDR_SIZE);
180 if (unlikely((tc->flags & (TALLOC_FLAG_FREE | ~0xF)) != TALLOC_MAGIC)) {
181 if ((tc->flags & (~0xF)) == TALLOC_MAGIC_V1) {
182 talloc_abort_magic_v1();
185 if (tc->flags & TALLOC_FLAG_FREE) {
186 talloc_abort_double_free();
188 talloc_abort_unknown_value();
194 /* hook into the front of the list */
195 #define _TLIST_ADD(list, p) \
199 (p)->next = (p)->prev = NULL; \
201 (list)->prev = (p); \
202 (p)->next = (list); \
208 /* remove an element from a list - element doesn't have to be in list. */
209 #define _TLIST_REMOVE(list, p) \
211 if ((p) == (list)) { \
212 (list) = (p)->next; \
213 if (list) (list)->prev = NULL; \
215 if ((p)->prev) (p)->prev->next = (p)->next; \
216 if ((p)->next) (p)->next->prev = (p)->prev; \
218 if ((p) && ((p) != (list))) (p)->next = (p)->prev = NULL; \
223 return the parent chunk of a pointer
225 static inline struct talloc_chunk *talloc_parent_chunk(const void *ptr)
227 struct talloc_chunk *tc;
229 if (unlikely(ptr == NULL)) {
233 tc = talloc_chunk_from_ptr(ptr);
234 while (tc->prev) tc=tc->prev;
239 void *talloc_parent(const void *ptr)
241 struct talloc_chunk *tc = talloc_parent_chunk(ptr);
242 return tc? TC_PTR_FROM_CHUNK(tc) : NULL;
248 const char *talloc_parent_name(const void *ptr)
250 struct talloc_chunk *tc = talloc_parent_chunk(ptr);
251 return tc? tc->name : NULL;
255 A pool carries an in-pool object count count in the first 16 bytes.
256 bytes. This is done to support talloc_steal() to a parent outside of the
257 pool. The count includes the pool itself, so a talloc_free() on a pool will
258 only destroy the pool if the count has dropped to zero. A talloc_free() of a
259 pool member will reduce the count, and eventually also call free(3) on the
262 The object count is not put into "struct talloc_chunk" because it is only
263 relevant for talloc pools and the alignment to 16 bytes would increase the
264 memory footprint of each talloc chunk by those 16 bytes.
267 #define TALLOC_POOL_HDR_SIZE 16
269 static unsigned int *talloc_pool_objectcount(struct talloc_chunk *tc)
271 return (unsigned int *)((char *)tc + sizeof(struct talloc_chunk));
278 static struct talloc_chunk *talloc_alloc_pool(struct talloc_chunk *parent,
281 struct talloc_chunk *pool_ctx = NULL;
283 struct talloc_chunk *result;
286 if (parent == NULL) {
290 if (parent->flags & TALLOC_FLAG_POOL) {
293 else if (parent->flags & TALLOC_FLAG_POOLMEM) {
294 pool_ctx = (struct talloc_chunk *)parent->pool;
297 if (pool_ctx == NULL) {
301 space_left = ((char *)pool_ctx + TC_HDR_SIZE + pool_ctx->size)
302 - ((char *)pool_ctx->pool);
305 * Align size to 16 bytes
307 chunk_size = ((size + 15) & ~15);
309 if (space_left < chunk_size) {
313 result = (struct talloc_chunk *)pool_ctx->pool;
315 #if defined(DEVELOPER) && defined(VALGRIND_MAKE_MEM_UNDEFINED)
316 VALGRIND_MAKE_MEM_UNDEFINED(result, size);
319 pool_ctx->pool = (void *)((char *)result + chunk_size);
321 result->flags = TALLOC_MAGIC | TALLOC_FLAG_POOLMEM;
322 result->pool = pool_ctx;
324 *talloc_pool_objectcount(pool_ctx) += 1;
330 Allocate a bit of memory as a child of an existing pointer
332 static inline void *__talloc(const void *context, size_t size)
334 struct talloc_chunk *tc = NULL;
336 if (unlikely(context == NULL)) {
337 context = null_context;
340 if (unlikely(size >= MAX_TALLOC_SIZE)) {
344 if (context != NULL) {
345 tc = talloc_alloc_pool(talloc_chunk_from_ptr(context),
350 tc = (struct talloc_chunk *)malloc(TC_HDR_SIZE+size);
351 if (unlikely(tc == NULL)) return NULL;
352 tc->flags = TALLOC_MAGIC;
357 tc->destructor = NULL;
362 if (likely(context)) {
363 struct talloc_chunk *parent = talloc_chunk_from_ptr(context);
366 parent->child->parent = NULL;
367 tc->next = parent->child;
376 tc->next = tc->prev = tc->parent = NULL;
379 return TC_PTR_FROM_CHUNK(tc);
383 * Create a talloc pool
386 void *talloc_pool(const void *context, size_t size)
388 void *result = __talloc(context, size + TALLOC_POOL_HDR_SIZE);
389 struct talloc_chunk *tc;
391 if (unlikely(result == NULL)) {
395 tc = talloc_chunk_from_ptr(result);
397 tc->flags |= TALLOC_FLAG_POOL;
398 tc->pool = (char *)result + TALLOC_POOL_HDR_SIZE;
400 *talloc_pool_objectcount(tc) = 1;
402 #if defined(DEVELOPER) && defined(VALGRIND_MAKE_MEM_NOACCESS)
403 VALGRIND_MAKE_MEM_NOACCESS(tc->pool, size);
410 setup a destructor to be called on free of a pointer
411 the destructor should return 0 on success, or -1 on failure.
412 if the destructor fails then the free is failed, and the memory can
413 be continued to be used
415 void _talloc_set_destructor(const void *ptr, int (*destructor)(void *))
417 struct talloc_chunk *tc = talloc_chunk_from_ptr(ptr);
418 tc->destructor = destructor;
422 increase the reference count on a piece of memory.
424 int talloc_increase_ref_count(const void *ptr)
426 if (unlikely(!talloc_reference(null_context, ptr))) {
433 helper for talloc_reference()
435 this is referenced by a function pointer and should not be inline
437 static int talloc_reference_destructor(struct talloc_reference_handle *handle)
439 struct talloc_chunk *ptr_tc = talloc_chunk_from_ptr(handle->ptr);
440 _TLIST_REMOVE(ptr_tc->refs, handle);
445 more efficient way to add a name to a pointer - the name must point to a
448 static inline void _talloc_set_name_const(const void *ptr, const char *name)
450 struct talloc_chunk *tc = talloc_chunk_from_ptr(ptr);
455 internal talloc_named_const()
457 static inline void *_talloc_named_const(const void *context, size_t size, const char *name)
461 ptr = __talloc(context, size);
462 if (unlikely(ptr == NULL)) {
466 _talloc_set_name_const(ptr, name);
472 make a secondary reference to a pointer, hanging off the given context.
473 the pointer remains valid until both the original caller and this given
476 the major use for this is when two different structures need to reference the
477 same underlying data, and you want to be able to free the two instances separately,
480 void *_talloc_reference(const void *context, const void *ptr, const char *location)
482 struct talloc_chunk *tc;
483 struct talloc_reference_handle *handle;
484 if (unlikely(ptr == NULL)) return NULL;
486 tc = talloc_chunk_from_ptr(ptr);
487 handle = (struct talloc_reference_handle *)_talloc_named_const(context,
488 sizeof(struct talloc_reference_handle),
489 TALLOC_MAGIC_REFERENCE);
490 if (unlikely(handle == NULL)) return NULL;
492 /* note that we hang the destructor off the handle, not the
493 main context as that allows the caller to still setup their
494 own destructor on the context if they want to */
495 talloc_set_destructor(handle, talloc_reference_destructor);
496 handle->ptr = discard_const_p(void, ptr);
497 handle->location = location;
498 _TLIST_ADD(tc->refs, handle);
504 internal talloc_free call
506 static inline int _talloc_free_internal(void *ptr)
508 struct talloc_chunk *tc;
510 if (unlikely(ptr == NULL)) {
514 tc = talloc_chunk_from_ptr(ptr);
516 if (unlikely(tc->refs)) {
518 /* check this is a reference from a child or grantchild
519 * back to it's parent or grantparent
521 * in that case we need to remove the reference and
522 * call another instance of talloc_free() on the current
525 is_child = talloc_is_parent(tc->refs, ptr);
526 _talloc_free_internal(tc->refs);
528 return _talloc_free_internal(ptr);
533 if (unlikely(tc->flags & TALLOC_FLAG_LOOP)) {
534 /* we have a free loop - stop looping */
538 if (unlikely(tc->destructor)) {
539 talloc_destructor_t d = tc->destructor;
540 if (d == (talloc_destructor_t)-1) {
543 tc->destructor = (talloc_destructor_t)-1;
548 tc->destructor = NULL;
552 _TLIST_REMOVE(tc->parent->child, tc);
553 if (tc->parent->child) {
554 tc->parent->child->parent = tc->parent;
557 if (tc->prev) tc->prev->next = tc->next;
558 if (tc->next) tc->next->prev = tc->prev;
561 tc->flags |= TALLOC_FLAG_LOOP;
564 /* we need to work out who will own an abandoned child
565 if it cannot be freed. In priority order, the first
566 choice is owner of any remaining reference to this
567 pointer, the second choice is our parent, and the
568 final choice is the null context. */
569 void *child = TC_PTR_FROM_CHUNK(tc->child);
570 const void *new_parent = null_context;
571 if (unlikely(tc->child->refs)) {
572 struct talloc_chunk *p = talloc_parent_chunk(tc->child->refs);
573 if (p) new_parent = TC_PTR_FROM_CHUNK(p);
575 if (unlikely(_talloc_free_internal(child) == -1)) {
576 if (new_parent == null_context) {
577 struct talloc_chunk *p = talloc_parent_chunk(ptr);
578 if (p) new_parent = TC_PTR_FROM_CHUNK(p);
580 _talloc_steal_internal(new_parent, child);
584 tc->flags |= TALLOC_FLAG_FREE;
586 if (tc->flags & (TALLOC_FLAG_POOL|TALLOC_FLAG_POOLMEM)) {
587 struct talloc_chunk *pool;
588 unsigned int *pool_object_count;
590 pool = (tc->flags & TALLOC_FLAG_POOL)
591 ? tc : (struct talloc_chunk *)tc->pool;
593 pool_object_count = talloc_pool_objectcount(pool);
595 if (*pool_object_count == 0) {
596 talloc_abort("Pool object count zero!");
599 *pool_object_count -= 1;
601 if (*pool_object_count == 0) {
612 move a lump of memory from one talloc context to another return the
613 ptr on success, or NULL if it could not be transferred.
614 passing NULL as ptr will always return NULL with no side effects.
616 void *_talloc_steal_internal(const void *new_ctx, const void *ptr)
618 struct talloc_chunk *tc, *new_tc;
620 if (unlikely(!ptr)) {
624 if (unlikely(new_ctx == NULL)) {
625 new_ctx = null_context;
628 tc = talloc_chunk_from_ptr(ptr);
630 if (unlikely(new_ctx == NULL)) {
632 _TLIST_REMOVE(tc->parent->child, tc);
633 if (tc->parent->child) {
634 tc->parent->child->parent = tc->parent;
637 if (tc->prev) tc->prev->next = tc->next;
638 if (tc->next) tc->next->prev = tc->prev;
641 tc->parent = tc->next = tc->prev = NULL;
642 return discard_const_p(void, ptr);
645 new_tc = talloc_chunk_from_ptr(new_ctx);
647 if (unlikely(tc == new_tc || tc->parent == new_tc)) {
648 return discard_const_p(void, ptr);
652 _TLIST_REMOVE(tc->parent->child, tc);
653 if (tc->parent->child) {
654 tc->parent->child->parent = tc->parent;
657 if (tc->prev) tc->prev->next = tc->next;
658 if (tc->next) tc->next->prev = tc->prev;
662 if (new_tc->child) new_tc->child->parent = NULL;
663 _TLIST_ADD(new_tc->child, tc);
665 return discard_const_p(void, ptr);
670 move a lump of memory from one talloc context to another return the
671 ptr on success, or NULL if it could not be transferred.
672 passing NULL as ptr will always return NULL with no side effects.
674 void *_talloc_steal(const void *new_ctx, const void *ptr, const char *location)
676 struct talloc_chunk *tc;
678 if (unlikely(ptr == NULL)) {
682 tc = talloc_chunk_from_ptr(ptr);
684 if (unlikely(tc->refs != NULL) && talloc_parent(ptr) != new_ctx) {
685 struct talloc_reference_handle *h;
686 fprintf(stderr, "ERROR: talloc_steal with references at %s\n", location);
687 for (h=tc->refs; h; h=h->next) {
688 fprintf(stderr, "\treference at %s\n", h->location);
693 return _talloc_steal_internal(new_ctx, ptr);
697 this is like a talloc_steal(), but you must supply the old
698 parent. This resolves the ambiguity in a talloc_steal() which is
699 called on a context that has more than one parent (via references)
701 The old parent can be either a reference or a parent
703 void *talloc_reparent(const void *old_parent, const void *new_parent, const void *ptr)
705 struct talloc_chunk *tc;
706 struct talloc_reference_handle *h;
708 if (unlikely(ptr == NULL)) {
712 if (old_parent == talloc_parent(ptr)) {
713 return _talloc_steal_internal(new_parent, ptr);
716 tc = talloc_chunk_from_ptr(ptr);
717 for (h=tc->refs;h;h=h->next) {
718 if (talloc_parent(h) == old_parent) {
719 if (_talloc_steal_internal(new_parent, h) != h) {
726 /* it wasn't a parent */
731 remove a secondary reference to a pointer. This undo's what
732 talloc_reference() has done. The context and pointer arguments
733 must match those given to a talloc_reference()
735 static inline int talloc_unreference(const void *context, const void *ptr)
737 struct talloc_chunk *tc = talloc_chunk_from_ptr(ptr);
738 struct talloc_reference_handle *h;
740 if (unlikely(context == NULL)) {
741 context = null_context;
744 for (h=tc->refs;h;h=h->next) {
745 struct talloc_chunk *p = talloc_parent_chunk(h);
747 if (context == NULL) break;
748 } else if (TC_PTR_FROM_CHUNK(p) == context) {
756 return _talloc_free_internal(h);
760 remove a specific parent context from a pointer. This is a more
761 controlled varient of talloc_free()
763 int talloc_unlink(const void *context, void *ptr)
765 struct talloc_chunk *tc_p, *new_p;
772 if (context == NULL) {
773 context = null_context;
776 if (talloc_unreference(context, ptr) == 0) {
780 if (context == NULL) {
781 if (talloc_parent_chunk(ptr) != NULL) {
785 if (talloc_chunk_from_ptr(context) != talloc_parent_chunk(ptr)) {
790 tc_p = talloc_chunk_from_ptr(ptr);
792 if (tc_p->refs == NULL) {
793 return _talloc_free_internal(ptr);
796 new_p = talloc_parent_chunk(tc_p->refs);
798 new_parent = TC_PTR_FROM_CHUNK(new_p);
803 if (talloc_unreference(new_parent, ptr) != 0) {
807 _talloc_steal_internal(new_parent, ptr);
813 add a name to an existing pointer - va_list version
815 static inline const char *talloc_set_name_v(const void *ptr, const char *fmt, va_list ap) PRINTF_ATTRIBUTE(2,0);
817 static inline const char *talloc_set_name_v(const void *ptr, const char *fmt, va_list ap)
819 struct talloc_chunk *tc = talloc_chunk_from_ptr(ptr);
820 tc->name = talloc_vasprintf(ptr, fmt, ap);
821 if (likely(tc->name)) {
822 _talloc_set_name_const(tc->name, ".name");
828 add a name to an existing pointer
830 const char *talloc_set_name(const void *ptr, const char *fmt, ...)
835 name = talloc_set_name_v(ptr, fmt, ap);
842 create a named talloc pointer. Any talloc pointer can be named, and
843 talloc_named() operates just like talloc() except that it allows you
846 void *talloc_named(const void *context, size_t size, const char *fmt, ...)
852 ptr = __talloc(context, size);
853 if (unlikely(ptr == NULL)) return NULL;
856 name = talloc_set_name_v(ptr, fmt, ap);
859 if (unlikely(name == NULL)) {
860 _talloc_free_internal(ptr);
868 return the name of a talloc ptr, or "UNNAMED"
870 const char *talloc_get_name(const void *ptr)
872 struct talloc_chunk *tc = talloc_chunk_from_ptr(ptr);
873 if (unlikely(tc->name == TALLOC_MAGIC_REFERENCE)) {
876 if (likely(tc->name)) {
884 check if a pointer has the given name. If it does, return the pointer,
885 otherwise return NULL
887 void *talloc_check_name(const void *ptr, const char *name)
890 if (unlikely(ptr == NULL)) return NULL;
891 pname = talloc_get_name(ptr);
892 if (likely(pname == name || strcmp(pname, name) == 0)) {
893 return discard_const_p(void, ptr);
898 static void talloc_abort_type_missmatch(const char *location,
900 const char *expected)
904 reason = talloc_asprintf(NULL,
905 "%s: Type mismatch: name[%s] expected[%s]",
910 reason = "Type mismatch";
913 talloc_abort(reason);
916 void *_talloc_get_type_abort(const void *ptr, const char *name, const char *location)
920 if (unlikely(ptr == NULL)) {
921 talloc_abort_type_missmatch(location, NULL, name);
925 pname = talloc_get_name(ptr);
926 if (likely(pname == name || strcmp(pname, name) == 0)) {
927 return discard_const_p(void, ptr);
930 talloc_abort_type_missmatch(location, pname, name);
935 this is for compatibility with older versions of talloc
937 void *talloc_init(const char *fmt, ...)
944 * samba3 expects talloc_report_depth_cb(NULL, ...)
945 * reports all talloc'ed memory, so we need to enable
948 talloc_enable_null_tracking();
950 ptr = __talloc(NULL, 0);
951 if (unlikely(ptr == NULL)) return NULL;
954 name = talloc_set_name_v(ptr, fmt, ap);
957 if (unlikely(name == NULL)) {
958 _talloc_free_internal(ptr);
966 this is a replacement for the Samba3 talloc_destroy_pool functionality. It
967 should probably not be used in new code. It's in here to keep the talloc
968 code consistent across Samba 3 and 4.
970 void talloc_free_children(void *ptr)
972 struct talloc_chunk *tc;
974 if (unlikely(ptr == NULL)) {
978 tc = talloc_chunk_from_ptr(ptr);
981 /* we need to work out who will own an abandoned child
982 if it cannot be freed. In priority order, the first
983 choice is owner of any remaining reference to this
984 pointer, the second choice is our parent, and the
985 final choice is the null context. */
986 void *child = TC_PTR_FROM_CHUNK(tc->child);
987 const void *new_parent = null_context;
988 if (unlikely(tc->child->refs)) {
989 struct talloc_chunk *p = talloc_parent_chunk(tc->child->refs);
990 if (p) new_parent = TC_PTR_FROM_CHUNK(p);
992 if (unlikely(talloc_free(child) == -1)) {
993 if (new_parent == null_context) {
994 struct talloc_chunk *p = talloc_parent_chunk(ptr);
995 if (p) new_parent = TC_PTR_FROM_CHUNK(p);
997 _talloc_steal_internal(new_parent, child);
1001 if ((tc->flags & TALLOC_FLAG_POOL)
1002 && (*talloc_pool_objectcount(tc) == 1)) {
1003 tc->pool = ((char *)tc + TC_HDR_SIZE + TALLOC_POOL_HDR_SIZE);
1004 #if defined(DEVELOPER) && defined(VALGRIND_MAKE_MEM_NOACCESS)
1005 VALGRIND_MAKE_MEM_NOACCESS(
1006 tc->pool, tc->size - TALLOC_POOL_HDR_SIZE);
1012 Allocate a bit of memory as a child of an existing pointer
1014 void *_talloc(const void *context, size_t size)
1016 return __talloc(context, size);
1020 externally callable talloc_set_name_const()
1022 void talloc_set_name_const(const void *ptr, const char *name)
1024 _talloc_set_name_const(ptr, name);
1028 create a named talloc pointer. Any talloc pointer can be named, and
1029 talloc_named() operates just like talloc() except that it allows you
1030 to name the pointer.
1032 void *talloc_named_const(const void *context, size_t size, const char *name)
1034 return _talloc_named_const(context, size, name);
1038 free a talloc pointer. This also frees all child pointers of this
1041 return 0 if the memory is actually freed, otherwise -1. The memory
1042 will not be freed if the ref_count is > 1 or the destructor (if
1043 any) returns non-zero
1045 int _talloc_free(void *ptr, const char *location)
1047 struct talloc_chunk *tc;
1049 if (unlikely(ptr == NULL)) {
1053 tc = talloc_chunk_from_ptr(ptr);
1055 if (unlikely(tc->refs != NULL)) {
1056 struct talloc_reference_handle *h;
1057 fprintf(stderr, "ERROR: talloc_free with references at %s\n", location);
1058 for (h=tc->refs; h; h=h->next) {
1059 fprintf(stderr, "\treference at %s\n", h->location);
1064 return _talloc_free_internal(ptr);
1070 A talloc version of realloc. The context argument is only used if
1073 void *_talloc_realloc(const void *context, void *ptr, size_t size, const char *name)
1075 struct talloc_chunk *tc;
1077 bool malloced = false;
1079 /* size zero is equivalent to free() */
1080 if (unlikely(size == 0)) {
1081 talloc_unlink(context, ptr);
1085 if (unlikely(size >= MAX_TALLOC_SIZE)) {
1089 /* realloc(NULL) is equivalent to malloc() */
1091 return _talloc_named_const(context, size, name);
1094 tc = talloc_chunk_from_ptr(ptr);
1096 /* don't allow realloc on referenced pointers */
1097 if (unlikely(tc->refs)) {
1101 /* don't let anybody try to realloc a talloc_pool */
1102 if (unlikely(tc->flags & TALLOC_FLAG_POOL)) {
1106 /* don't shrink if we have less than 1k to gain */
1107 if ((size < tc->size) && ((tc->size - size) < 1024)) {
1112 /* by resetting magic we catch users of the old memory */
1113 tc->flags |= TALLOC_FLAG_FREE;
1116 new_ptr = malloc(size + TC_HDR_SIZE);
1118 memcpy(new_ptr, tc, tc->size + TC_HDR_SIZE);
1122 if (tc->flags & TALLOC_FLAG_POOLMEM) {
1124 new_ptr = talloc_alloc_pool(tc, size + TC_HDR_SIZE);
1125 *talloc_pool_objectcount((struct talloc_chunk *)
1128 if (new_ptr == NULL) {
1129 new_ptr = malloc(TC_HDR_SIZE+size);
1134 memcpy(new_ptr, tc, MIN(tc->size,size) + TC_HDR_SIZE);
1138 new_ptr = realloc(tc, size + TC_HDR_SIZE);
1141 if (unlikely(!new_ptr)) {
1142 tc->flags &= ~TALLOC_FLAG_FREE;
1146 tc = (struct talloc_chunk *)new_ptr;
1147 tc->flags &= ~TALLOC_FLAG_FREE;
1149 tc->flags &= ~TALLOC_FLAG_POOLMEM;
1152 tc->parent->child = tc;
1155 tc->child->parent = tc;
1159 tc->prev->next = tc;
1162 tc->next->prev = tc;
1166 _talloc_set_name_const(TC_PTR_FROM_CHUNK(tc), name);
1168 return TC_PTR_FROM_CHUNK(tc);
1172 a wrapper around talloc_steal() for situations where you are moving a pointer
1173 between two structures, and want the old pointer to be set to NULL
1175 void *_talloc_move(const void *new_ctx, const void *_pptr)
1177 const void **pptr = discard_const_p(const void *,_pptr);
1178 void *ret = talloc_steal(new_ctx, *pptr);
1184 return the total size of a talloc pool (subtree)
1186 size_t talloc_total_size(const void *ptr)
1189 struct talloc_chunk *c, *tc;
1198 tc = talloc_chunk_from_ptr(ptr);
1200 if (tc->flags & TALLOC_FLAG_LOOP) {
1204 tc->flags |= TALLOC_FLAG_LOOP;
1207 for (c=tc->child;c;c=c->next) {
1208 total += talloc_total_size(TC_PTR_FROM_CHUNK(c));
1211 tc->flags &= ~TALLOC_FLAG_LOOP;
1217 return the total number of blocks in a talloc pool (subtree)
1219 size_t talloc_total_blocks(const void *ptr)
1222 struct talloc_chunk *c, *tc = talloc_chunk_from_ptr(ptr);
1224 if (tc->flags & TALLOC_FLAG_LOOP) {
1228 tc->flags |= TALLOC_FLAG_LOOP;
1231 for (c=tc->child;c;c=c->next) {
1232 total += talloc_total_blocks(TC_PTR_FROM_CHUNK(c));
1235 tc->flags &= ~TALLOC_FLAG_LOOP;
1241 return the number of external references to a pointer
1243 size_t talloc_reference_count(const void *ptr)
1245 struct talloc_chunk *tc = talloc_chunk_from_ptr(ptr);
1246 struct talloc_reference_handle *h;
1249 for (h=tc->refs;h;h=h->next) {
1256 report on memory usage by all children of a pointer, giving a full tree view
1258 void talloc_report_depth_cb(const void *ptr, int depth, int max_depth,
1259 void (*callback)(const void *ptr,
1260 int depth, int max_depth,
1262 void *private_data),
1265 struct talloc_chunk *c, *tc;
1270 if (ptr == NULL) return;
1272 tc = talloc_chunk_from_ptr(ptr);
1274 if (tc->flags & TALLOC_FLAG_LOOP) {
1278 callback(ptr, depth, max_depth, 0, private_data);
1280 if (max_depth >= 0 && depth >= max_depth) {
1284 tc->flags |= TALLOC_FLAG_LOOP;
1285 for (c=tc->child;c;c=c->next) {
1286 if (c->name == TALLOC_MAGIC_REFERENCE) {
1287 struct talloc_reference_handle *h = (struct talloc_reference_handle *)TC_PTR_FROM_CHUNK(c);
1288 callback(h->ptr, depth + 1, max_depth, 1, private_data);
1290 talloc_report_depth_cb(TC_PTR_FROM_CHUNK(c), depth + 1, max_depth, callback, private_data);
1293 tc->flags &= ~TALLOC_FLAG_LOOP;
1296 static void talloc_report_depth_FILE_helper(const void *ptr, int depth, int max_depth, int is_ref, void *_f)
1298 const char *name = talloc_get_name(ptr);
1299 FILE *f = (FILE *)_f;
1302 fprintf(f, "%*sreference to: %s\n", depth*4, "", name);
1307 fprintf(f,"%stalloc report on '%s' (total %6lu bytes in %3lu blocks)\n",
1308 (max_depth < 0 ? "full " :""), name,
1309 (unsigned long)talloc_total_size(ptr),
1310 (unsigned long)talloc_total_blocks(ptr));
1314 fprintf(f, "%*s%-30s contains %6lu bytes in %3lu blocks (ref %d) %p\n",
1317 (unsigned long)talloc_total_size(ptr),
1318 (unsigned long)talloc_total_blocks(ptr),
1319 (int)talloc_reference_count(ptr), ptr);
1322 fprintf(f, "content: ");
1323 if (talloc_total_size(ptr)) {
1324 int tot = talloc_total_size(ptr);
1327 for (i = 0; i < tot; i++) {
1328 if ((((char *)ptr)[i] > 31) && (((char *)ptr)[i] < 126)) {
1329 fprintf(f, "%c", ((char *)ptr)[i]);
1331 fprintf(f, "~%02x", ((char *)ptr)[i]);
1340 report on memory usage by all children of a pointer, giving a full tree view
1342 void talloc_report_depth_file(const void *ptr, int depth, int max_depth, FILE *f)
1344 talloc_report_depth_cb(ptr, depth, max_depth, talloc_report_depth_FILE_helper, f);
1349 report on memory usage by all children of a pointer, giving a full tree view
1351 void talloc_report_full(const void *ptr, FILE *f)
1353 talloc_report_depth_file(ptr, 0, -1, f);
1357 report on memory usage by all children of a pointer
1359 void talloc_report(const void *ptr, FILE *f)
1361 talloc_report_depth_file(ptr, 0, 1, f);
1365 report on any memory hanging off the null context
1367 static void talloc_report_null(void)
1369 if (talloc_total_size(null_context) != 0) {
1370 talloc_report(null_context, stderr);
1375 report on any memory hanging off the null context
1377 static void talloc_report_null_full(void)
1379 if (talloc_total_size(null_context) != 0) {
1380 talloc_report_full(null_context, stderr);
1385 enable tracking of the NULL context
1387 void talloc_enable_null_tracking(void)
1389 if (null_context == NULL) {
1390 null_context = _talloc_named_const(NULL, 0, "null_context");
1395 disable tracking of the NULL context
1397 void talloc_disable_null_tracking(void)
1399 talloc_free(null_context);
1400 null_context = NULL;
1404 enable leak reporting on exit
1406 void talloc_enable_leak_report(void)
1408 talloc_enable_null_tracking();
1409 atexit(talloc_report_null);
1413 enable full leak reporting on exit
1415 void talloc_enable_leak_report_full(void)
1417 talloc_enable_null_tracking();
1418 atexit(talloc_report_null_full);
1422 talloc and zero memory.
1424 void *_talloc_zero(const void *ctx, size_t size, const char *name)
1426 void *p = _talloc_named_const(ctx, size, name);
1429 memset(p, '\0', size);
1436 memdup with a talloc.
1438 void *_talloc_memdup(const void *t, const void *p, size_t size, const char *name)
1440 void *newp = _talloc_named_const(t, size, name);
1443 memcpy(newp, p, size);
1449 static inline char *__talloc_strlendup(const void *t, const char *p, size_t len)
1453 ret = (char *)__talloc(t, len + 1);
1454 if (unlikely(!ret)) return NULL;
1456 memcpy(ret, p, len);
1459 _talloc_set_name_const(ret, ret);
1464 strdup with a talloc
1466 char *talloc_strdup(const void *t, const char *p)
1468 if (unlikely(!p)) return NULL;
1469 return __talloc_strlendup(t, p, strlen(p));
1473 strndup with a talloc
1475 char *talloc_strndup(const void *t, const char *p, size_t n)
1477 if (unlikely(!p)) return NULL;
1478 return __talloc_strlendup(t, p, strnlen(p, n));
1481 static inline char *__talloc_strlendup_append(char *s, size_t slen,
1482 const char *a, size_t alen)
1486 ret = talloc_realloc(NULL, s, char, slen + alen + 1);
1487 if (unlikely(!ret)) return NULL;
1489 /* append the string and the trailing \0 */
1490 memcpy(&ret[slen], a, alen);
1493 _talloc_set_name_const(ret, ret);
1498 * Appends at the end of the string.
1500 char *talloc_strdup_append(char *s, const char *a)
1503 return talloc_strdup(NULL, a);
1510 return __talloc_strlendup_append(s, strlen(s), a, strlen(a));
1514 * Appends at the end of the talloc'ed buffer,
1515 * not the end of the string.
1517 char *talloc_strdup_append_buffer(char *s, const char *a)
1522 return talloc_strdup(NULL, a);
1529 slen = talloc_get_size(s);
1530 if (likely(slen > 0)) {
1534 return __talloc_strlendup_append(s, slen, a, strlen(a));
1538 * Appends at the end of the string.
1540 char *talloc_strndup_append(char *s, const char *a, size_t n)
1543 return talloc_strdup(NULL, a);
1550 return __talloc_strlendup_append(s, strlen(s), a, strnlen(a, n));
1554 * Appends at the end of the talloc'ed buffer,
1555 * not the end of the string.
1557 char *talloc_strndup_append_buffer(char *s, const char *a, size_t n)
1562 return talloc_strdup(NULL, a);
1569 slen = talloc_get_size(s);
1570 if (likely(slen > 0)) {
1574 return __talloc_strlendup_append(s, slen, a, strnlen(a, n));
1577 #ifndef HAVE_VA_COPY
1578 #ifdef HAVE___VA_COPY
1579 #define va_copy(dest, src) __va_copy(dest, src)
1581 #define va_copy(dest, src) (dest) = (src)
1585 char *talloc_vasprintf(const void *t, const char *fmt, va_list ap)
1592 /* this call looks strange, but it makes it work on older solaris boxes */
1594 len = vsnprintf(&c, 1, fmt, ap2);
1596 if (unlikely(len < 0)) {
1600 ret = (char *)__talloc(t, len+1);
1601 if (unlikely(!ret)) return NULL;
1604 vsnprintf(ret, len+1, fmt, ap2);
1607 _talloc_set_name_const(ret, ret);
1613 Perform string formatting, and return a pointer to newly allocated
1614 memory holding the result, inside a memory pool.
1616 char *talloc_asprintf(const void *t, const char *fmt, ...)
1622 ret = talloc_vasprintf(t, fmt, ap);
1627 static inline char *__talloc_vaslenprintf_append(char *s, size_t slen,
1628 const char *fmt, va_list ap)
1629 PRINTF_ATTRIBUTE(3,0);
1631 static inline char *__talloc_vaslenprintf_append(char *s, size_t slen,
1632 const char *fmt, va_list ap)
1639 alen = vsnprintf(&c, 1, fmt, ap2);
1643 /* Either the vsnprintf failed or the format resulted in
1644 * no characters being formatted. In the former case, we
1645 * ought to return NULL, in the latter we ought to return
1646 * the original string. Most current callers of this
1647 * function expect it to never return NULL.
1652 s = talloc_realloc(NULL, s, char, slen + alen + 1);
1653 if (!s) return NULL;
1656 vsnprintf(s + slen, alen + 1, fmt, ap2);
1659 _talloc_set_name_const(s, s);
1664 * Realloc @p s to append the formatted result of @p fmt and @p ap,
1665 * and return @p s, which may have moved. Good for gradually
1666 * accumulating output into a string buffer. Appends at the end
1669 char *talloc_vasprintf_append(char *s, const char *fmt, va_list ap)
1672 return talloc_vasprintf(NULL, fmt, ap);
1675 return __talloc_vaslenprintf_append(s, strlen(s), fmt, ap);
1679 * Realloc @p s to append the formatted result of @p fmt and @p ap,
1680 * and return @p s, which may have moved. Always appends at the
1681 * end of the talloc'ed buffer, not the end of the string.
1683 char *talloc_vasprintf_append_buffer(char *s, const char *fmt, va_list ap)
1688 return talloc_vasprintf(NULL, fmt, ap);
1691 slen = talloc_get_size(s);
1692 if (likely(slen > 0)) {
1696 return __talloc_vaslenprintf_append(s, slen, fmt, ap);
1700 Realloc @p s to append the formatted result of @p fmt and return @p
1701 s, which may have moved. Good for gradually accumulating output
1702 into a string buffer.
1704 char *talloc_asprintf_append(char *s, const char *fmt, ...)
1709 s = talloc_vasprintf_append(s, fmt, ap);
1715 Realloc @p s to append the formatted result of @p fmt and return @p
1716 s, which may have moved. Good for gradually accumulating output
1719 char *talloc_asprintf_append_buffer(char *s, const char *fmt, ...)
1724 s = talloc_vasprintf_append_buffer(s, fmt, ap);
1730 alloc an array, checking for integer overflow in the array size
1732 void *_talloc_array(const void *ctx, size_t el_size, unsigned count, const char *name)
1734 if (count >= MAX_TALLOC_SIZE/el_size) {
1737 return _talloc_named_const(ctx, el_size * count, name);
1741 alloc an zero array, checking for integer overflow in the array size
1743 void *_talloc_zero_array(const void *ctx, size_t el_size, unsigned count, const char *name)
1745 if (count >= MAX_TALLOC_SIZE/el_size) {
1748 return _talloc_zero(ctx, el_size * count, name);
1752 realloc an array, checking for integer overflow in the array size
1754 void *_talloc_realloc_array(const void *ctx, void *ptr, size_t el_size, unsigned count, const char *name)
1756 if (count >= MAX_TALLOC_SIZE/el_size) {
1759 return _talloc_realloc(ctx, ptr, el_size * count, name);
1763 a function version of talloc_realloc(), so it can be passed as a function pointer
1764 to libraries that want a realloc function (a realloc function encapsulates
1765 all the basic capabilities of an allocation library, which is why this is useful)
1767 void *talloc_realloc_fn(const void *context, void *ptr, size_t size)
1769 return _talloc_realloc(context, ptr, size, NULL);
1773 static int talloc_autofree_destructor(void *ptr)
1775 autofree_context = NULL;
1779 static void talloc_autofree(void)
1781 talloc_free(autofree_context);
1785 return a context which will be auto-freed on exit
1786 this is useful for reducing the noise in leak reports
1788 void *talloc_autofree_context(void)
1790 if (autofree_context == NULL) {
1791 autofree_context = _talloc_named_const(NULL, 0, "autofree_context");
1792 talloc_set_destructor(autofree_context, talloc_autofree_destructor);
1793 atexit(talloc_autofree);
1795 return autofree_context;
1798 size_t talloc_get_size(const void *context)
1800 struct talloc_chunk *tc;
1802 if (context == NULL)
1805 tc = talloc_chunk_from_ptr(context);
1811 find a parent of this context that has the given name, if any
1813 void *talloc_find_parent_byname(const void *context, const char *name)
1815 struct talloc_chunk *tc;
1817 if (context == NULL) {
1821 tc = talloc_chunk_from_ptr(context);
1823 if (tc->name && strcmp(tc->name, name) == 0) {
1824 return TC_PTR_FROM_CHUNK(tc);
1826 while (tc && tc->prev) tc = tc->prev;
1835 show the parentage of a context
1837 void talloc_show_parents(const void *context, FILE *file)
1839 struct talloc_chunk *tc;
1841 if (context == NULL) {
1842 fprintf(file, "talloc no parents for NULL\n");
1846 tc = talloc_chunk_from_ptr(context);
1847 fprintf(file, "talloc parents of '%s'\n", talloc_get_name(context));
1849 fprintf(file, "\t'%s'\n", talloc_get_name(TC_PTR_FROM_CHUNK(tc)));
1850 while (tc && tc->prev) tc = tc->prev;
1859 return 1 if ptr is a parent of context
1861 int talloc_is_parent(const void *context, const void *ptr)
1863 struct talloc_chunk *tc;
1865 if (context == NULL) {
1869 tc = talloc_chunk_from_ptr(context);
1871 if (TC_PTR_FROM_CHUNK(tc) == ptr) return 1;
1872 while (tc && tc->prev) tc = tc->prev;