Make avcodec_decode_* functions take const input buffers.

Originally committed as revision 11823 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/avcodec.h

@@ -2611,7 +2611,7 @@ int avcodec_open(AVCodecContext *avctx, AVCodec *codec);
  */
 attribute_deprecated int avcodec_decode_audio(AVCodecContext *avctx, int16_t *samples,
                          int *frame_size_ptr,
-                         uint8_t *buf, int buf_size);
+                         const uint8_t *buf, int buf_size);
 
 /**
  * Decodes an audio frame from \p buf into \p samples.
@@ -2651,7 +2651,7 @@ attribute_deprecated int avcodec_decode_audio(AVCodecContext *avctx, int16_t *sa
  */
 int avcodec_decode_audio2(AVCodecContext *avctx, int16_t *samples,
                          int *frame_size_ptr,
-                         uint8_t *buf, int buf_size);
+                         const uint8_t *buf, int buf_size);
 
 /**
  * Decodes a video frame from \p buf into \p picture.
@@ -2686,7 +2686,7 @@ int avcodec_decode_audio2(AVCodecContext *avctx, int16_t *samples,
  */
 int avcodec_decode_video(AVCodecContext *avctx, AVFrame *picture,
                          int *got_picture_ptr,
-                         uint8_t *buf, int buf_size);
+                         const uint8_t *buf, int buf_size);
 
 /* Decode a subtitle message. Return -1 if error, otherwise return the
  * number of bytes used. If no subtitle could be decompressed,

libavcodec/utils.c

@@ -934,7 +934,7 @@ int avcodec_encode_subtitle(AVCodecContext *avctx, uint8_t *buf, int buf_size,
 
 int attribute_align_arg avcodec_decode_video(AVCodecContext *avctx, AVFrame *picture,
                          int *got_picture_ptr,
-                         uint8_t *buf, int buf_size)
+                         const uint8_t *buf, int buf_size)
 {
     int ret;
 
@@ -957,7 +957,7 @@ int attribute_align_arg avcodec_decode_video(AVCodecContext *avctx, AVFrame *pic
 
 int attribute_align_arg avcodec_decode_audio2(AVCodecContext *avctx, int16_t *samples,
                          int *frame_size_ptr,
-                         uint8_t *buf, int buf_size)
+                         const uint8_t *buf, int buf_size)
 {
     int ret;
 
@@ -986,7 +986,7 @@ int attribute_align_arg avcodec_decode_audio2(AVCodecContext *avctx, int16_t *sa
 #if LIBAVCODEC_VERSION_INT < ((52<<16)+(0<<8)+0)
 int avcodec_decode_audio(AVCodecContext *avctx, int16_t *samples,
                          int *frame_size_ptr,
-                         uint8_t *buf, int buf_size){
+                         const uint8_t *buf, int buf_size){
     *frame_size_ptr= AVCODEC_MAX_AUDIO_FRAME_SIZE;
     return avcodec_decode_audio2(avctx, samples, frame_size_ptr, buf, buf_size);
 }