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/*
Unix SMB/Netbios implementation.
Version 3.0
Samba temporary memory allocation functions
Copyright (C) Andrew Tridgell 2000
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
/* this is a very simple temporary memory allocator. To use it do the following:
1) when you first want to allocate a pool of meomry use
talloc_init() and save the resulting context pointer somewhere
2) to allocate memory use talloc()
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
*/
#include "includes.h"
#define TALLOC_ALIGN 32
#define TALLOC_CHUNK_SIZE (0x2000)
/* initialissa talloc context. */
TALLOC_CTX *talloc_init(void)
{
TALLOC_CTX *t;
t = (TALLOC_CTX *)malloc(sizeof(*t));
if (!t) return NULL;
t->list = NULL;
t->total_alloc_size = 0;
return t;
}
/* allocate a bit of memory from the specified pool */
void *talloc(TALLOC_CTX *t, size_t size)
{
void *p;
if (size == 0)
{
/* debugging value used to track down
memory problems. BAD_PTR is defined
in talloc.h */
p = BAD_PTR;
return p;
}
/* normal code path */
size = (size + (TALLOC_ALIGN-1)) & ~(TALLOC_ALIGN-1);
if (!t->list || (t->list->total_size - t->list->alloc_size) < size) {
struct talloc_chunk *c;
size_t asize = (size + (TALLOC_CHUNK_SIZE-1)) & ~(TALLOC_CHUNK_SIZE-1);
c = (struct talloc_chunk *)malloc(sizeof(*c));
if (!c) return NULL;
c->next = t->list;
c->ptr = (void *)malloc(asize);
if (!c->ptr) {
free(c);
return NULL;
}
c->alloc_size = 0;
c->total_size = asize;
t->list = c;
t->total_alloc_size += asize;
}
p = ((char *)t->list->ptr) + t->list->alloc_size;
t->list->alloc_size += size;
return p;
}
/* destroy a whole pool */
void talloc_destroy_pool(TALLOC_CTX *t)
{
struct talloc_chunk *c;
if (!t)
return;
while (t->list) {
c = t->list->next;
free(t->list->ptr);
free(t->list);
t->list = c;
}
t->list = NULL;
t->total_alloc_size = 0;
}
/* destroy a whole pool including the context */
void talloc_destroy(TALLOC_CTX *t)
{
if (!t)
return;
talloc_destroy_pool(t);
free(t);
}
/* return the current total size of the pool. */
size_t talloc_pool_size(TALLOC_CTX *t)
{
if (!t->list)
return 0;
return t->total_alloc_size;
}
/* talloc and zero memory. */
void *talloc_zero(TALLOC_CTX *t, size_t size)
{
void *p = talloc(t, size);
if (p)
memset(p, '\0', size);
return p;
}
/* memdup with a talloc. */
void *talloc_memdup(TALLOC_CTX *t, void *p, size_t size)
{
void *newp = talloc(t,size);
if (!newp)
return 0;
memcpy(newp, p, size);
return newp;
}
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