ffmpeg/libavutil/buffer_internal.h

112 lines
3.0 KiB
C

/*
* 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 "internal.h"
#include "buffer.h"
#include "thread.h"
/**
* The buffer was av_realloc()ed, so it is reallocatable.
*/
#define BUFFER_FLAG_REALLOCATABLE (1 << 0)
/**
* The AVBuffer structure is part of a larger structure
* and should not be freed.
*/
#define BUFFER_FLAG_NO_FREE (1 << 1)
struct AVBuffer {
uint8_t *data; /**< data described by this buffer */
size_t 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 AV_BUFFER_FLAG_*
*/
int flags;
/**
* A combination of BUFFER_FLAG_*
*/
int flags_internal;
};
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;
/*
* An AVBuffer structure to (re)use as AVBuffer for subsequent uses
* of this BufferPoolEntry.
*/
AVBuffer buffer;
} 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;
size_t size;
void *opaque;
AVBufferRef* (*alloc)(size_t size);
AVBufferRef* (*alloc2)(void *opaque, size_t size);
void (*pool_free)(void *opaque);
};
#endif /* AVUTIL_BUFFER_INTERNAL_H */