From 27079a426c9d3db918b158976e44b9b143d78e1c Mon Sep 17 00:00:00 2001
From: Anton Khirnov <anton@khirnov.net>
Date: Sun, 17 Jul 2016 22:24:35 +0200
Subject: [PATCH] buffer: convert to stdatomic

---
 libavutil/buffer.c          | 21 +++++++++++----------
 libavutil/buffer_internal.h |  5 +++--
 2 files changed, 14 insertions(+), 12 deletions(-)

diff --git a/libavutil/buffer.c b/libavutil/buffer.c
index 49a1f2d395..0e2b4ef1b4 100644
--- a/libavutil/buffer.c
+++ b/libavutil/buffer.c
@@ -16,10 +16,10 @@
  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
+#include <stdatomic.h>
 #include <stdint.h>
 #include <string.h>
 
-#include "atomic.h"
 #include "buffer_internal.h"
 #include "common.h"
 #include "mem.h"
@@ -40,7 +40,8 @@ AVBufferRef *av_buffer_create(uint8_t *data, int size,
     buf->size     = size;
     buf->free     = free ? free : av_buffer_default_free;
     buf->opaque   = opaque;
-    buf->refcount = 1;
+
+    atomic_init(&buf->refcount, 1);
 
     if (flags & AV_BUFFER_FLAG_READONLY)
         buf->flags |= BUFFER_FLAG_READONLY;
@@ -98,7 +99,7 @@ AVBufferRef *av_buffer_ref(AVBufferRef *buf)
 
     *ret = *buf;
 
-    avpriv_atomic_int_add_and_fetch(&buf->buffer->refcount, 1);
+    atomic_fetch_add_explicit(&buf->buffer->refcount, 1, memory_order_relaxed);
 
     return ret;
 }
@@ -112,7 +113,7 @@ void av_buffer_unref(AVBufferRef **buf)
     b = (*buf)->buffer;
     av_freep(buf);
 
-    if (!avpriv_atomic_int_add_and_fetch(&b->refcount, -1)) {
+    if (atomic_fetch_add_explicit(&b->refcount, -1, memory_order_acq_rel) == 1) {
         b->free(b->opaque, b->data);
         av_freep(&b);
     }
@@ -123,7 +124,7 @@ int av_buffer_is_writable(const AVBufferRef *buf)
     if (buf->buffer->flags & AV_BUFFER_FLAG_READONLY)
         return 0;
 
-    return avpriv_atomic_int_add_and_fetch(&buf->buffer->refcount, 0) == 1;
+    return atomic_load(&buf->buffer->refcount) == 1;
 }
 
 int av_buffer_make_writable(AVBufferRef **pbuf)
@@ -209,7 +210,7 @@ AVBufferPool *av_buffer_pool_init2(int size, void *opaque,
     pool->alloc2    = alloc;
     pool->pool_free = pool_free;
 
-    avpriv_atomic_int_set(&pool->refcount, 1);
+    atomic_init(&pool->refcount, 1);
 
     return pool;
 }
@@ -225,7 +226,7 @@ AVBufferPool *av_buffer_pool_init(int size, AVBufferRef* (*alloc)(int size))
     pool->size     = size;
     pool->alloc    = alloc ? alloc : av_buffer_alloc;
 
-    avpriv_atomic_int_set(&pool->refcount, 1);
+    atomic_init(&pool->refcount, 1);
 
     return pool;
 }
@@ -260,7 +261,7 @@ void av_buffer_pool_uninit(AVBufferPool **ppool)
     pool   = *ppool;
     *ppool = NULL;
 
-    if (!avpriv_atomic_int_add_and_fetch(&pool->refcount, -1))
+    if (atomic_fetch_add_explicit(&pool->refcount, -1, memory_order_acq_rel) == 1)
         buffer_pool_free(pool);
 }
 
@@ -274,7 +275,7 @@ static void pool_release_buffer(void *opaque, uint8_t *data)
     pool->pool = buf;
     ff_mutex_unlock(&pool->mutex);
 
-    if (!avpriv_atomic_int_add_and_fetch(&pool->refcount, -1))
+    if (atomic_fetch_add_explicit(&pool->refcount, -1, memory_order_acq_rel) == 1)
         buffer_pool_free(pool);
 }
 
@@ -327,7 +328,7 @@ AVBufferRef *av_buffer_pool_get(AVBufferPool *pool)
     ff_mutex_unlock(&pool->mutex);
 
     if (ret)
-        avpriv_atomic_int_add_and_fetch(&pool->refcount, 1);
+        atomic_fetch_add_explicit(&pool->refcount, 1, memory_order_relaxed);
 
     return ret;
 }
diff --git a/libavutil/buffer_internal.h b/libavutil/buffer_internal.h
index 64344d8262..90d68aacac 100644
--- a/libavutil/buffer_internal.h
+++ b/libavutil/buffer_internal.h
@@ -19,6 +19,7 @@
 #ifndef AVUTIL_BUFFER_INTERNAL_H
 #define AVUTIL_BUFFER_INTERNAL_H
 
+#include <stdatomic.h>
 #include <stdint.h>
 
 #include "buffer.h"
@@ -40,7 +41,7 @@ struct AVBuffer {
     /**
      *  number of existing AVBufferRef instances referring to this buffer
      */
-    volatile int refcount;
+    atomic_uint refcount;
 
     /**
      * a callback for freeing the data
@@ -85,7 +86,7 @@ struct AVBufferPool {
      * buffers have been released, then it's safe to free the pool and all
      * the buffers in it.
      */
-    volatile int refcount;
+    atomic_uint refcount;
 
     int size;
     void *opaque;