mirror of
https://git.ffmpeg.org/ffmpeg.git
synced 2024-12-13 10:44:59 +00:00
121 lines
3.1 KiB
C
121 lines
3.1 KiB
C
/*
|
|
* A very simple circular buffer FIFO implementation
|
|
* Copyright (c) 2000, 2001, 2002 Fabrice Bellard
|
|
* Copyright (c) 2006 Roman Shaposhnik
|
|
*
|
|
* 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 "common.h"
|
|
#include "fifo.h"
|
|
|
|
int av_fifo_init(AVFifoBuffer *f, int size)
|
|
{
|
|
f->buffer = av_malloc(size);
|
|
if (!f->buffer)
|
|
return -1;
|
|
f->end = f->buffer + size;
|
|
f->wptr = f->rptr = f->buffer;
|
|
return 0;
|
|
}
|
|
|
|
void av_fifo_free(AVFifoBuffer *f)
|
|
{
|
|
av_free(f->buffer);
|
|
}
|
|
|
|
int av_fifo_size(AVFifoBuffer *f)
|
|
{
|
|
int size = f->wptr - f->rptr;
|
|
if (size < 0)
|
|
size += f->end - f->buffer;
|
|
return size;
|
|
}
|
|
|
|
/**
|
|
* Get data from the fifo (returns -1 if not enough data).
|
|
*/
|
|
int av_fifo_read(AVFifoBuffer *f, uint8_t *buf, int buf_size)
|
|
{
|
|
return av_fifo_generic_read(f, buf_size, NULL, buf);
|
|
}
|
|
|
|
/**
|
|
* Resizes a FIFO.
|
|
*/
|
|
void av_fifo_realloc(AVFifoBuffer *f, unsigned int new_size) {
|
|
unsigned int old_size= f->end - f->buffer;
|
|
|
|
if(old_size < new_size){
|
|
uint8_t *old= f->buffer;
|
|
|
|
f->buffer= av_realloc(f->buffer, new_size);
|
|
|
|
f->rptr += f->buffer - old;
|
|
f->wptr += f->buffer - old;
|
|
|
|
if(f->wptr < f->rptr){
|
|
memmove(f->rptr + new_size - old_size, f->rptr, f->buffer + old_size - f->rptr);
|
|
f->rptr += new_size - old_size;
|
|
}
|
|
f->end= f->buffer + new_size;
|
|
}
|
|
}
|
|
|
|
void av_fifo_write(AVFifoBuffer *f, const uint8_t *buf, int size)
|
|
{
|
|
while (size > 0) {
|
|
int len = FFMIN(f->end - f->wptr, size);
|
|
memcpy(f->wptr, buf, len);
|
|
f->wptr += len;
|
|
if (f->wptr >= f->end)
|
|
f->wptr = f->buffer;
|
|
buf += len;
|
|
size -= len;
|
|
}
|
|
}
|
|
|
|
|
|
/* get data from the fifo (return -1 if not enough data) */
|
|
int av_fifo_generic_read(AVFifoBuffer *f, int buf_size, void (*func)(void*, void*, int), void* dest)
|
|
{
|
|
int size = av_fifo_size(f);
|
|
|
|
if (size < buf_size)
|
|
return -1;
|
|
while (buf_size > 0) {
|
|
int len = FFMIN(f->end - f->rptr, buf_size);
|
|
if(func) func(dest, f->rptr, len);
|
|
else{
|
|
memcpy(dest, f->rptr, len);
|
|
dest = (uint8_t*)dest + len;
|
|
}
|
|
f->rptr += len;
|
|
if (f->rptr >= f->end)
|
|
f->rptr = f->buffer;
|
|
buf_size -= len;
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
/* discard data from the fifo */
|
|
void av_fifo_drain(AVFifoBuffer *f, int size)
|
|
{
|
|
f->rptr += size;
|
|
if (f->rptr >= f->end)
|
|
f->rptr -= f->end - f->buffer;
|
|
}
|