avresample: Mark avresample_buffer() as pointer to const

That buffer is read only and marking it accordingly let
the user passing a constant buffer to it without having
a const-correctness warning.
Signed-off-by: Luca Barbato <lu_zero@gentoo.org>

libavresample/audio_data.c

@@ -70,9 +70,10 @@ int ff_audio_data_set_channels(AudioData *a, int channels)
     return 0;
 }
 
-int ff_audio_data_init(AudioData *a, uint8_t **src, int plane_size, int channels,
-                       int nb_samples, enum AVSampleFormat sample_fmt,
-                       int read_only, const char *name)
+int ff_audio_data_init(AudioData *a, uint8_t * const *src, int plane_size,
+                       int channels, int nb_samples,
+                       enum AVSampleFormat sample_fmt, int read_only,
+                       const char *name)
 {
     int p;
 

libavresample/audio_data.h

@@ -76,9 +76,10 @@ int ff_audio_data_set_channels(AudioData *a, int channels);
  * @param name            name for debug logging (can be NULL)
  * @return                0 on success, negative AVERROR value on error
  */
-int ff_audio_data_init(AudioData *a, uint8_t **src, int plane_size, int channels,
-                       int nb_samples, enum AVSampleFormat sample_fmt,
-                       int read_only, const char *name);
+int ff_audio_data_init(AudioData *a, uint8_t * const *src, int plane_size,
+                       int channels, int nb_samples,
+                       enum AVSampleFormat sample_fmt, int read_only,
+                       const char *name);
 
 /**
  * Allocate AudioData.

libavresample/avresample.h

@@ -377,8 +377,9 @@ int avresample_get_out_samples(AVAudioResampleContext *avr, int in_nb_samples);
  *                        output FIFO
  */
 int avresample_convert(AVAudioResampleContext *avr, uint8_t **output,
-                       int out_plane_size, int out_samples, uint8_t **input,
-                       int in_plane_size, int in_samples);
+                       int out_plane_size, int out_samples,
+                       uint8_t * const *input, int in_plane_size,
+                       int in_samples);
 
 /**
  * Return the number of samples currently in the resampling delay buffer.

libavresample/utils.c

@@ -329,7 +329,8 @@ static int handle_buffered_output(AVAudioResampleContext *avr,
 
 int attribute_align_arg avresample_convert(AVAudioResampleContext *avr,
                                            uint8_t **output, int out_plane_size,
-                                           int out_samples, uint8_t **input,
+                                           int out_samples,
+                                           uint8_t * const *input,
                                            int in_plane_size, int in_samples)
 {
     AudioData input_buffer;