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Diffstat (limited to 'contrib/ffmpeg/libavutil/fifo.c')
-rw-r--r-- | contrib/ffmpeg/libavutil/fifo.c | 114 |
1 files changed, 114 insertions, 0 deletions
diff --git a/contrib/ffmpeg/libavutil/fifo.c b/contrib/ffmpeg/libavutil/fifo.c new file mode 100644 index 000000000..8ac3a0cb5 --- /dev/null +++ b/contrib/ffmpeg/libavutil/fifo.c @@ -0,0 +1,114 @@ +/* + * 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->wptr = f->rptr = + f->buffer = av_malloc(size); + f->end = f->buffer + size; + if (!f->buffer) + return -1; + 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){ + int len= av_fifo_size(f); + AVFifoBuffer f2; + + av_fifo_init(&f2, new_size); + av_fifo_read(f, f2.buffer, len); + f2.wptr += len; + av_free(f->buffer); + *f= f2; + } +} + +void av_fifo_write(AVFifoBuffer *f, const uint8_t *buf, int size) +{ + do { + 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; + } while (size > 0); +} + + +/** 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; + do { + 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; + } + av_fifo_drain(f, len); + buf_size -= len; + } while (buf_size > 0); + 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; +} |