/*
- * This file is part of FFmpeg.
+ * This file is part of Libav.
*
- * FFmpeg is free software; you can redistribute it and/or
+ * Libav 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,
+ * Libav 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
+ * License along with Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
- * @file libavutil/fifo.h
+ * @file
* a very simple circular buffer FIFO implementation
*/
#include <stdint.h>
#include "avutil.h"
-#include "common.h"
+#include "attributes.h"
typedef struct AVFifoBuffer {
uint8_t *buffer;
} AVFifoBuffer;
/**
- * Initializes an AVFifoBuffer.
- * @param *f AVFifoBuffer to initialize
+ * Initialize an AVFifoBuffer.
* @param size of FIFO
- * @return <0 for failure >=0 otherwise
+ * @return AVFifoBuffer or NULL in case of memory allocation failure
*/
-int av_fifo_init(AVFifoBuffer *f, unsigned int size);
+AVFifoBuffer *av_fifo_alloc(unsigned int size);
/**
- * Frees an AVFifoBuffer.
- * @param *f AVFifoBuffer to free
+ * Free an AVFifoBuffer.
+ * @param f AVFifoBuffer to free
*/
void av_fifo_free(AVFifoBuffer *f);
/**
- * Returns the amount of data in bytes in the AVFifoBuffer, that is the
+ * Reset the AVFifoBuffer to the state right after av_fifo_alloc, in particular it is emptied.
+ * @param f AVFifoBuffer to reset
+ */
+void av_fifo_reset(AVFifoBuffer *f);
+
+/**
+ * Return the amount of data in bytes in the AVFifoBuffer, that is the
* amount of data you can read from it.
- * @param *f AVFifoBuffer to read from
+ * @param f AVFifoBuffer to read from
* @return size
*/
int av_fifo_size(AVFifoBuffer *f);
/**
- * Reads data from an AVFifoBuffer.
- * @param *f AVFifoBuffer to read from
- * @param *buf data destination
- * @param buf_size number of bytes to read
+ * Return the amount of space in bytes in the AVFifoBuffer, that is the
+ * amount of data you can write into it.
+ * @param f AVFifoBuffer to write into
+ * @return size
*/
-int av_fifo_read(AVFifoBuffer *f, uint8_t *buf, int buf_size);
+int av_fifo_space(AVFifoBuffer *f);
/**
- * Feeds data from an AVFifoBuffer to a user-supplied callback.
- * @param *f AVFifoBuffer to read from
+ * Feed data from an AVFifoBuffer to a user-supplied callback.
+ * @param f AVFifoBuffer to read from
* @param buf_size number of bytes to read
- * @param *func generic read function
- * @param *dest data destination
- */
-int av_fifo_generic_read(AVFifoBuffer *f, int buf_size, void (*func)(void*, void*, int), void* dest);
-
-#if LIBAVUTIL_VERSION_MAJOR < 50
-/**
- * Writes data into an AVFifoBuffer.
- * @param *f AVFifoBuffer to write to
- * @param *buf data source
- * @param size data size
+ * @param func generic read function
+ * @param dest data destination
*/
-attribute_deprecated void av_fifo_write(AVFifoBuffer *f, const uint8_t *buf, int size);
-#endif
+int av_fifo_generic_read(AVFifoBuffer *f, void *dest, int buf_size, void (*func)(void*, void*, int));
/**
- * Feeds data from a user-supplied callback to an AVFifoBuffer.
- * @param *f AVFifoBuffer to write to
- * @param *src data source
+ * Feed data from a user-supplied callback to an AVFifoBuffer.
+ * @param f AVFifoBuffer to write to
+ * @param src data source; non-const since it may be used as a
+ * modifiable context by the function defined in func
* @param size number of bytes to write
- * @param *func generic write function; the first parameter is src,
+ * @param func generic write function; the first parameter is src,
* the second is dest_buf, the third is dest_buf_size.
* func must return the number of bytes written to dest_buf, or <= 0 to
* indicate no more data available to write.
*/
int av_fifo_generic_write(AVFifoBuffer *f, void *src, int size, int (*func)(void*, void*, int));
-#if LIBAVUTIL_VERSION_MAJOR < 50
/**
- * Resizes an AVFifoBuffer.
- * @param *f AVFifoBuffer to resize
- * @param size new AVFifoBuffer size in bytes
- * @see av_fifo_realloc2()
- */
-attribute_deprecated void av_fifo_realloc(AVFifoBuffer *f, unsigned int size);
-#endif
-
-/**
- * Resizes an AVFifoBuffer.
- * @param *f AVFifoBuffer to resize
+ * Resize an AVFifoBuffer.
+ * @param f AVFifoBuffer to resize
* @param size new AVFifoBuffer size in bytes
* @return <0 for failure, >=0 otherwise
*/
int av_fifo_realloc2(AVFifoBuffer *f, unsigned int size);
/**
- * Reads and discards the specified amount of data from an AVFifoBuffer.
- * @param *f AVFifoBuffer to read from
+ * Read and discard the specified amount of data from an AVFifoBuffer.
+ * @param f AVFifoBuffer to read from
* @param size amount of data to read in bytes
*/
void av_fifo_drain(AVFifoBuffer *f, int size);
-static inline uint8_t av_fifo_peek(AVFifoBuffer *f, int offs)
+/**
+ * Return a pointer to the data stored in a FIFO buffer at a certain offset.
+ * The FIFO buffer is not modified.
+ *
+ * @param f AVFifoBuffer to peek at, f must be non-NULL
+ * @param offs an offset in bytes, its absolute value must be less
+ * than the used buffer size or the returned pointer will
+ * point outside to the buffer data.
+ * The used buffer size can be checked with av_fifo_size().
+ */
+static inline uint8_t *av_fifo_peek2(const AVFifoBuffer *f, int offs)
{
uint8_t *ptr = f->rptr + offs;
if (ptr >= f->end)
- ptr -= f->end - f->buffer;
- return *ptr;
+ ptr = f->buffer + (ptr - f->end);
+ else if (ptr < f->buffer)
+ ptr = f->end - (f->buffer - ptr);
+ return ptr;
}
+
#endif /* AVUTIL_FIFO_H */
projects / ffmpeg / blobdiff