/* 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; 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; }; wrapper->refcount = (int *)((char *)wrapper->ptr + refcount_offset); *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; wrapper = talloc(context, struct wrapper); if (wrapper == NULL) { return NULL; } wrapper->ptr = source; wrapper->refcount = (int *)((char *)wrapper->ptr + refcount_offset); (*wrapper->refcount)++; talloc_set_destructor(wrapper, refcount_destructor); return wrapper->ptr; }