/*
SSSD
Simple reference counting wrappers for talloc.
Authors:
Martin Nagy <mnagy@redhat.com>
Copyright (C) Red Hat, Inc 2009
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 3 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, see <http://www.gnu.org/licenses/>.
*/
#include <talloc.h>
#include "refcount.h"
#include "util/util.h"
struct wrapper {
int *refcount;
void *ptr;
};
static int
refcount_destructor(struct wrapper *wrapper)
{
(*wrapper->refcount)--;
if (*wrapper->refcount == 0) {
talloc_free(wrapper->ptr);
};
return 0;
}
void *
_rc_alloc(const void *context, size_t size, size_t refcount_offset,
const char *type_name)
{
struct wrapper *wrapper;
char *refcount_pos;
wrapper = talloc(context, struct wrapper);
if (wrapper == NULL) {
return NULL;
}
wrapper->ptr = talloc_named_const(NULL, size, type_name);
if (wrapper->ptr == NULL) {
talloc_free(wrapper);
return NULL;
};
refcount_pos = (char *)wrapper->ptr + refcount_offset;
wrapper->refcount = DISCARD_ALIGN(refcount_pos, int *);
*wrapper->refcount = 1;
talloc_set_destructor(wrapper, refcount_destructor);
return wrapper->ptr;
}
void *
_rc_reference(const void *context, size_t refcount_offset, void *source)
{
struct wrapper *wrapper;
char *refcount_pos;
wrapper = talloc(context, struct wrapper);
if (wrapper == NULL) {
return NULL;
}
wrapper->ptr = source;
refcount_pos = (char *)wrapper->ptr + refcount_offset;
wrapper->refcount = DISCARD_ALIGN(refcount_pos, int *);
(*wrapper->refcount)++;
talloc_set_destructor(wrapper, refcount_destructor);
return wrapper->ptr;
}