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/*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg 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
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
#include <stdatomic.h>
#include "refcount.h"
typedef struct AVRefcountImpl {
void (*free)(void *opaque);
void *opaque;
atomic_uint refcount;
} AVRefcountImpl;
void av_refcount_init(AVRefcount *rc, void (*free)(void *opaque),
void *opaque)
{
AVRefcountImpl *rci = (AVRefcountImpl*)rc;
rci->free = free;
rci->opaque = opaque;
atomic_init(&rci->refcount, 1);
}
void av_refcount_inc(AVRefcount *rc)
{
AVRefcountImpl *rci = (AVRefcountImpl*)rc;
atomic_fetch_add_explicit(&rci->refcount, 1, memory_order_relaxed);
}
unsigned int av_refcount_dec(AVRefcount *rc)
{
AVRefcountImpl *rci = (AVRefcountImpl*)rc;
unsigned int ret = atomic_fetch_sub_explicit(&rci->refcount, 1,
memory_order_acq_rel) - 1;
if (!ret && rci->free)
rci->free(rci->opaque);
return ret;
}
int av_refcount_exclusive(AVRefcount *rc)
{
AVRefcountImpl *rci = (AVRefcountImpl*)rc;
return atomic_load(&rci->refcount) == 1;
}
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