ffmpeg roll of source to mar 9 version...

patched-ffmpeg-mt/libavutil/fifo.h

 /*
  * 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
@@ skipping 63 matching lines @@
  * @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, 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
+ * @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,
  * 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.
  * If func is NULL, src is interpreted as a simple byte array for source data.
  * @return the number of bytes written to the FIFO
  */
 int av_fifo_generic_write(AVFifoBuffer *f, void *src, int size, int (*func)(void*, void*, int));
 
@@ skipping 13 matching lines @@
 void av_fifo_drain(AVFifoBuffer *f, int size);
 
 static inline uint8_t av_fifo_peek(AVFifoBuffer *f, int offs)
 {
     uint8_t *ptr = f->rptr + offs;
     if (ptr >= f->end)
         ptr -= f->end - f->buffer;
     return *ptr;
 }
 #endif /* AVUTIL_FIFO_H */