avutil/buffer: constify some function parameters

Reviewed-by: Andreas Rheinhardt <andreas.rheinhardt@outlook.com>
Signed-off-by: James Almer <jamrial@gmail.com>

doc/APIchanges

@@ -14,6 +14,10 @@ libavutil:     2021-04-27
 
 API changes, most recent first:
 
+2021-09-17 - xxxxxxxxxx - lavu 57.5.101 - buffer.h
+  Constified the input parameters in av_buffer_replace(), av_buffer_ref(),
+  and av_buffer_pool_buffer_get_opaque().
+
 2021-09-08 - xxxxxxxxxx - lavu 57.5.100 - hwcontext_d3d11va.h
   Add AVD3D11VAFramesContext.texture_infos
 

libavutil/buffer.c

@@ -90,7 +90,7 @@ AVBufferRef *av_buffer_allocz(size_t size)
     return ret;
 }
 
-AVBufferRef *av_buffer_ref(AVBufferRef *buf)
+AVBufferRef *av_buffer_ref(const AVBufferRef *buf)
 {
     AVBufferRef *ret = av_mallocz(sizeof(*ret));
 
@@ -216,7 +216,7 @@ int av_buffer_realloc(AVBufferRef **pbuf, size_t size)
     return 0;
 }
 
-int av_buffer_replace(AVBufferRef **pdst, AVBufferRef *src)
+int av_buffer_replace(AVBufferRef **pdst, const AVBufferRef *src)
 {
     AVBufferRef *dst = *pdst;
     AVBufferRef *tmp;
@@ -395,7 +395,7 @@ AVBufferRef *av_buffer_pool_get(AVBufferPool *pool)
     return ret;
 }
 
-void *av_buffer_pool_buffer_get_opaque(AVBufferRef *ref)
+void *av_buffer_pool_buffer_get_opaque(const AVBufferRef *ref)
 {
     BufferPoolEntry *buf = ref->buffer->opaque;
     av_assert0(buf);

libavutil/buffer.h

@@ -145,7 +145,7 @@ void av_buffer_default_free(void *opaque, uint8_t *data);
  * @return a new AVBufferRef referring to the same AVBuffer as buf or NULL on
  * failure.
  */
-AVBufferRef *av_buffer_ref(AVBufferRef *buf);
+AVBufferRef *av_buffer_ref(const AVBufferRef *buf);
 
 /**
  * Free a given reference and automatically free the buffer if there are no more
@@ -212,7 +212,7 @@ int av_buffer_realloc(AVBufferRef **buf, size_t size);
  * @return 0 on success
  *         AVERROR(ENOMEM) on memory allocation failure.
  */
-int av_buffer_replace(AVBufferRef **dst, AVBufferRef *src);
+int av_buffer_replace(AVBufferRef **dst, const AVBufferRef *src);
 
 /**
  * @}
@@ -313,7 +313,7 @@ AVBufferRef *av_buffer_pool_get(AVBufferPool *pool);
  * therefore you have to use this function to access the original opaque
  * parameter of an allocated buffer.
  */
-void *av_buffer_pool_buffer_get_opaque(AVBufferRef *ref);
+void *av_buffer_pool_buffer_get_opaque(const AVBufferRef *ref);
 
 /**
  * @}

libavutil/version.h

@@ -80,7 +80,7 @@
 
 #define LIBAVUTIL_VERSION_MAJOR  57
 #define LIBAVUTIL_VERSION_MINOR   5
-#define LIBAVUTIL_VERSION_MICRO 100
+#define LIBAVUTIL_VERSION_MICRO 101
 
 #define LIBAVUTIL_VERSION_INT   AV_VERSION_INT(LIBAVUTIL_VERSION_MAJOR, \
                                                LIBAVUTIL_VERSION_MINOR, \