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-rw-r--r--source4/lib/talloc.c288
1 files changed, 151 insertions, 137 deletions
diff --git a/source4/lib/talloc.c b/source4/lib/talloc.c
index 59d4eac500..92e0d52d2d 100644
--- a/source4/lib/talloc.c
+++ b/source4/lib/talloc.c
@@ -33,32 +33,27 @@
3) when _all_ of the memory allocated using this context is no longer needed
use talloc_destroy()
- talloc does not zero the memory. It guarantees memory of a
- TALLOC_ALIGN alignment
+ talloc does not zero the memory.
@sa talloc.h
*/
/**
- * @todo We could allocate both the talloc_chunk structure, and the
- * memory it contains all in one allocation, which might be a bit
- * faster and perhaps use less memory overhead.
- *
- * That smells like a premature optimization, though. -- mbp
- **/
-
-/**
* If you want testing for memory corruption use valgrind
**/
#include "includes.h"
#define MAX_TALLOC_SIZE 0x10000000
+#define TALLOC_MAGIC 0x06052004
+#define TALLOC_MAGIC_FREE 0x3421abcd
struct talloc_chunk {
- struct talloc_chunk *next;
+ struct talloc_chunk *next, *prev;
+ TALLOC_CTX *context;
size_t size;
void *ptr;
+ unsigned magic;
};
@@ -160,26 +155,26 @@ static TALLOC_CTX *talloc_init_internal(void)
/** Allocate a bit of memory from the specified pool **/
void *talloc(TALLOC_CTX *t, size_t size)
{
- void *p;
struct talloc_chunk *tc;
- if (!t || size == 0) return NULL;
+ if (!t || size == 0) {
+ return NULL;
+ }
- p = malloc(size);
- if (p) {
- tc = malloc(sizeof(*tc));
- if (tc) {
- tc->ptr = p;
- tc->size = size;
- tc->next = t->list;
- t->list = tc;
- t->total_alloc_size += size;
- }
- else {
- SAFE_FREE(p);
- }
+ tc = malloc(sizeof(*tc)+size);
+ if (!tc) {
+ return NULL;
}
- return p;
+
+ tc->context = t;
+ tc->size = size;
+ tc->magic = TALLOC_MAGIC;
+
+ DLIST_ADD(t->list, tc);
+
+ t->total_alloc_size += size;
+
+ return (void *)(tc+1);
}
/** A talloc version of realloc */
@@ -199,37 +194,134 @@ void *talloc_realloc(TALLOC_CTX *t, void *ptr, size_t size)
}
/* realloc(NULL) is equavalent to malloc() */
- if (ptr == NULL)
+ if (ptr == NULL) {
return talloc(t, size);
+ }
- for (tc=t->list; tc; tc=tc->next) {
- if (tc->ptr == ptr) {
- new_ptr = Realloc(ptr, size);
- if (new_ptr) {
- t->total_alloc_size += (size - tc->size);
- tc->size = size;
- tc->ptr = new_ptr;
- }
- return new_ptr;
- }
+ tc = ((struct talloc_chunk *)ptr)-1;
+
+ if (tc->context != t) {
+ DEBUG(0,("Bad talloc context passed to talloc_realloc\n"));
+ return NULL;
}
- return NULL;
+
+ if (tc->magic != TALLOC_MAGIC) {
+ DEBUG(0,("Bad talloc magic 0x%08x in talloc_realloc\n", tc->magic));
+ return NULL;
+ }
+
+ /* by resetting magic we catch users of the old memory */
+ tc->magic = TALLOC_MAGIC_FREE;
+
+ new_ptr = realloc(tc, size + sizeof(*tc));
+ if (!new_ptr) {
+ tc->magic = TALLOC_MAGIC;
+ return NULL;
+ }
+
+ if (tc == t->list) {
+ t->list = new_ptr;
+ }
+ tc = new_ptr;
+ tc->magic = TALLOC_MAGIC;
+
+ if (tc->prev) {
+ tc->prev->next = tc;
+ }
+ if (tc->next) {
+ tc->next->prev = tc;
+ }
+
+ t->total_alloc_size += (size - tc->size);
+ tc->size = size;
+
+ return (void *)(tc+1);
}
+/*
+ free a lump from a pool. Use sparingly please.
+*/
+void talloc_free(TALLOC_CTX *ctx, void *ptr)
+{
+ struct talloc_chunk *tc;
+
+ if (!ptr || !ctx->list) return;
+
+ tc = ((struct talloc_chunk *)ptr)-1;
+
+ if (tc->context != ctx) {
+ DEBUG(0,("Bad talloc context passed to talloc_free\n"));
+ }
+
+ if (tc->magic != TALLOC_MAGIC) {
+ DEBUG(0,("Bad talloc magic 0x%08x in talloc_free\n", tc->magic));
+ }
+
+ DLIST_REMOVE(ctx->list, tc);
+
+ ctx->total_alloc_size -= tc->size;
+ tc->magic = TALLOC_MAGIC_FREE;
+
+ free(tc);
+}
+
+
+/*
+ move a lump of memory from one talloc context to another
+ return the ptr on success, or NULL if it could not be found
+ in the old context or could not be transferred
+*/
+void *talloc_steal(TALLOC_CTX *old_ctx, TALLOC_CTX *new_ctx, void *ptr)
+{
+ struct talloc_chunk *tc;
+
+ if (!ptr) {
+ return NULL;
+ }
+
+ tc = ((struct talloc_chunk *)ptr)-1;
+
+ if (tc->context != old_ctx) {
+ DEBUG(0,("Bad talloc context passed to talloc_steal\n"));
+ return NULL;
+ }
+
+ if (tc->magic != TALLOC_MAGIC) {
+ DEBUG(0,("Bad talloc magic 0x%08x in talloc_steal\n", tc->magic));
+ return NULL;
+ }
+
+ DLIST_REMOVE(old_ctx->list, tc);
+ DLIST_ADD(new_ctx->list, tc);
+
+ tc->context = new_ctx;
+
+ old_ctx->total_alloc_size -= tc->size;
+ new_ctx->total_alloc_size += tc->size;
+
+ return ptr;
+}
+
+
+
/** Destroy all the memory allocated inside @p t, but not @p t
* itself. */
void talloc_destroy_pool(TALLOC_CTX *t)
{
- struct talloc_chunk *c;
-
- if (!t)
+ if (!t) {
return;
+ }
while (t->list) {
- c = t->list->next;
- SAFE_FREE(t->list->ptr);
- SAFE_FREE(t->list);
- t->list = c;
+ struct talloc_chunk *tc = t->list;
+ if (tc->magic != TALLOC_MAGIC) {
+ DEBUG(0,("Bad magic 0x%08x in talloc_destroy_pool\n",
+ tc->magic));
+ return;
+ }
+ DLIST_REMOVE(t->list, tc);
+ tc->magic = TALLOC_MAGIC_FREE;
+ free(tc);
}
t->total_alloc_size = 0;
@@ -305,14 +397,6 @@ char *talloc_strndup(TALLOC_CTX *t, const char *p, size_t n)
return ret;
}
-/** strdup_w with a talloc */
-smb_ucs2_t *talloc_strdup_w(TALLOC_CTX *t, const smb_ucs2_t *p)
-{
- if (p)
- return talloc_memdup(t, p, (strlen_w(p) + 1) * sizeof(smb_ucs2_t));
- return NULL;
-}
-
/**
* Perform string formatting, and return a pointer to newly allocated
* memory holding the result, inside a memory pool.
@@ -463,99 +547,19 @@ void talloc_get_allocation(TALLOC_CTX *t,
size_t *total_bytes,
int *n_chunks)
{
- struct talloc_chunk *chunk;
+ struct talloc_chunk *tc;
if (t) {
*total_bytes = 0;
*n_chunks = 0;
- for (chunk = t->list; chunk; chunk = chunk->next) {
+ for (tc = t->list; tc; tc = tc->next) {
n_chunks[0]++;
- *total_bytes += chunk->size;
+ *total_bytes += tc->size;
}
}
}
-
-/*
- free a lump from a pool. Use sparingly please.
-*/
-void talloc_free(TALLOC_CTX *ctx, void *ptr)
-{
- struct talloc_chunk *tc;
-
- if (!ptr || !ctx->list) return;
-
- /* as a special case, see if its the first element in the
- list */
- if (ctx->list->ptr == ptr) {
- ctx->total_alloc_size -= ctx->list->size;
- tc = ctx->list;
- ctx->list = ctx->list->next;
- free(tc);
- free(ptr);
- return;
- }
-
- /* find it in the context */
- for (tc=ctx->list; tc->next; tc=tc->next) {
- if (tc->next->ptr == ptr) break;
- }
-
- if (tc->next) {
- struct talloc_chunk *tc2 = tc->next;
- ctx->total_alloc_size -= tc->next->size;
- tc->next = tc->next->next;
- free(tc2);
- free(ptr);
- } else {
- DEBUG(0,("Attempt to free non-allocated chunk in context '%s'\n",
- ctx->name));
- }
-}
-
-
-/*
- move a lump of memory from one talloc context to another
- return the ptr on success, or NULL if it could not be found
- in the old context or could not be transferred
-*/
-const void *talloc_steal(TALLOC_CTX *old_ctx, TALLOC_CTX *new_ctx, const void *ptr)
-{
- struct talloc_chunk *tc, *tc2;
-
- if (!ptr || !old_ctx->list) return NULL;
-
- /* as a special case, see if its the first element in the
- list */
- if (old_ctx->list->ptr == ptr) {
- tc = old_ctx->list;
- old_ctx->list = old_ctx->list->next;
- tc->next = new_ctx->list;
- new_ctx->list = tc;
- old_ctx->total_alloc_size -= tc->size;
- new_ctx->total_alloc_size += tc->size;
- return ptr;
- }
-
- /* find it in the old context */
- for (tc=old_ctx->list; tc->next; tc=tc->next) {
- if (tc->next->ptr == ptr) break;
- }
-
- if (!tc->next) return NULL;
-
- /* move it to the new context */
- tc2 = tc->next;
- tc->next = tc->next->next;
- tc2->next = new_ctx->list;
- new_ctx->list = tc2;
- old_ctx->total_alloc_size -= tc2->size;
- new_ctx->total_alloc_size += tc2->size;
-
- return ptr;
-}
-
/*
realloc an array, checking for integer overflow in the array size
*/
@@ -568,4 +572,14 @@ void *talloc_realloc_array(TALLOC_CTX *ctx, void *ptr, size_t el_size, unsigned
return talloc_realloc(ctx, ptr, el_size * count);
}
+
+/*
+ we really should get rid of this
+*/
+void *talloc_strdup_w(TALLOC_CTX *mem_ctx, void *s)
+{
+ size_t len = strlen_w(s);
+ return talloc_memdup(mem_ctx, s, (len+1)*2);
+}
+
/** @} */
generated by cgit (git 2.34.1) at 2024-11-10 13:40:44 +0000