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Diffstat (limited to 'lib/talloc/talloc.c')
| -rw-r--r-- | lib/talloc/talloc.c | 1732 |
1 files changed, 1732 insertions, 0 deletions
diff --git a/lib/talloc/talloc.c b/lib/talloc/talloc.c new file mode 100644 index 0000000000..1f7e52439f --- /dev/null +++ b/lib/talloc/talloc.c @@ -0,0 +1,1732 @@ +/* + 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/ +*/ + +#ifdef _SAMBA_BUILD_ +#include "version.h" +#if (SAMBA_VERSION_MAJOR<4) +#include "includes.h" +/* This is to circumvent SAMBA3's paranoid malloc checker. Here in this file + * we trust ourselves... */ +#ifdef malloc +#undef malloc +#endif +#ifdef realloc +#undef realloc +#endif +#define _TALLOC_SAMBA3 +#endif /* (SAMBA_VERSION_MAJOR<4) */ +#endif /* _SAMBA_BUILD_ */ + +#ifndef _TALLOC_SAMBA3 +#include "replace.h" +#include "talloc.h" +#endif /* not _TALLOC_SAMBA3 */ + +/* 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 0xe814ec70 +#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; +}; + +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)) + +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 & TALLOC_FLAG_FREE) { + talloc_abort_double_free(); + } else { + talloc_abort_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 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(const void *context, const void *ptr) +{ + 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); + _TLIST_ADD(tc->refs, handle); + return handle->ptr; +} + + +/* + internal talloc_free call +*/ +static inline int _talloc_free(void *ptr) +{ + 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(tc->refs); + if (is_child) { + return _talloc_free(ptr); + } + 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(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(new_parent, child); + } + } + + tc->flags |= TALLOC_FLAG_FREE; + + 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!"); + } + + *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. +*/ +void *_talloc_steal(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); +} + + + +/* + 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(h); +} + +/* + 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 = TC_PTR_FROM_CHUNK(new_p); + } 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 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(ptr); + 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; +} + + +/* + 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(ptr); + 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(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) +{ + return _talloc_free(ptr); +} + + + +/* + 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_free(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 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, *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; + + 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 = 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) +{ + 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"); + } +} + +/* + disable tracking of the NULL context +*/ +void talloc_disable_null_tracking(void) +{ + _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) + 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; +} |