Rename ffmpeg-4.2-fit to ffmpeg-4-fit

trunk/3rdparty/ffmpeg-4-fit/libavutil/buffer_internal.h

@@ -0,0 +1,98 @@
+/*
+ * 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
+ */
+
+#ifndef AVUTIL_BUFFER_INTERNAL_H
+#define AVUTIL_BUFFER_INTERNAL_H
+
+#include <stdatomic.h>
+#include <stdint.h>
+
+#include "buffer.h"
+#include "thread.h"
+
+/**
+ * The buffer is always treated as read-only.
+ */
+#define BUFFER_FLAG_READONLY      (1 << 0)
+/**
+ * The buffer was av_realloc()ed, so it is reallocatable.
+ */
+#define BUFFER_FLAG_REALLOCATABLE (1 << 1)
+
+struct AVBuffer {
+    uint8_t *data; /**< data described by this buffer */
+    int      size; /**< size of data in bytes */
+
+    /**
+     *  number of existing AVBufferRef instances referring to this buffer
+     */
+    atomic_uint refcount;
+
+    /**
+     * a callback for freeing the data
+     */
+    void (*free)(void *opaque, uint8_t *data);
+
+    /**
+     * an opaque pointer, to be used by the freeing callback
+     */
+    void *opaque;
+
+    /**
+     * A combination of BUFFER_FLAG_*
+     */
+    int flags;
+};
+
+typedef struct BufferPoolEntry {
+    uint8_t *data;
+
+    /*
+     * Backups of the original opaque/free of the AVBuffer corresponding to
+     * data. They will be used to free the buffer when the pool is freed.
+     */
+    void *opaque;
+    void (*free)(void *opaque, uint8_t *data);
+
+    AVBufferPool *pool;
+    struct BufferPoolEntry *next;
+} BufferPoolEntry;
+
+struct AVBufferPool {
+    AVMutex mutex;
+    BufferPoolEntry *pool;
+
+    /*
+     * This is used to track when the pool is to be freed.
+     * The pointer to the pool itself held by the caller is considered to
+     * be one reference. Each buffer requested by the caller increases refcount
+     * by one, returning the buffer to the pool decreases it by one.
+     * refcount reaches zero when the buffer has been uninited AND all the
+     * buffers have been released, then it's safe to free the pool and all
+     * the buffers in it.
+     */
+    atomic_uint refcount;
+
+    int size;
+    void *opaque;
+    AVBufferRef* (*alloc)(int size);
+    AVBufferRef* (*alloc2)(void *opaque, int size);
+    void         (*pool_free)(void *opaque);
+};
+
+#endif /* AVUTIL_BUFFER_INTERNAL_H */