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- /*-
- * Copyright 2016 Vsevolod Stakhov
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
- #ifndef REF_H_
- #define REF_H_
-
- #ifdef HAVE_CONFIG_H
- #include "config.h"
- #endif
-
-
- /**
- * @file ref.h
- * A set of macros to handle refcounts
- */
-
- typedef void (*ref_dtor_cb_t)(void *data);
-
- typedef struct ref_entry_s {
- unsigned int refcount;
- ref_dtor_cb_t dtor;
- } ref_entry_t;
-
- #define REF_INIT(obj, dtor_cb) do { \
- if ((obj) != NULL) { \
- (obj)->ref.refcount = 0; \
- (obj)->ref.dtor = (ref_dtor_cb_t)(dtor_cb); \
- } \
- } while (0)
-
- #define REF_INIT_RETAIN(obj, dtor_cb) do { \
- if ((obj) != NULL) { \
- (obj)->ref.refcount = 1; \
- (obj)->ref.dtor = (ref_dtor_cb_t)(dtor_cb); \
- } \
- } while (0)
-
- #ifdef HAVE_ATOMIC_BUILTINS
- #define REF_RETAIN_ATOMIC(obj) do { \
- if ((obj) != NULL) { \
- __atomic_add_fetch (&(obj)->ref.refcount, 1, __ATOMIC_RELEASE); \
- } \
- } while (0)
-
- #define REF_RELEASE_ATOMIC(obj) do { \
- if ((obj) != NULL) { \
- unsigned int _rc_priv = __atomic_sub_fetch (&(obj)->ref.refcount, 1, __ATOMIC_ACQ_REL); \
- if (_rc_priv == 0 && (obj)->ref.dtor) { \
- (obj)->ref.dtor (obj); \
- } \
- } \
- } while (0)
-
- #else
- #define REF_RETAIN_ATOMIC REF_RETAIN
- #define REF_RELEASE_ATOMIC REF_RELEASE_ATOMIC
- #endif
-
- #define REF_RETAIN(obj) do { \
- if ((obj) != NULL) { \
- (obj)->ref.refcount ++; \
- } \
- } while (0)
-
- #define REF_RELEASE(obj) do { \
- if ((obj) != NULL) { \
- if (--(obj)->ref.refcount == 0 && (obj)->ref.dtor) { \
- (obj)->ref.dtor (obj); \
- } \
- } \
- } while (0)
-
- #endif /* REF_H_ */
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