avutil/buffer: Switch AVBuffer API to size_t

[ffmpeg] / libavutil / buffer.h

diff --git a/libavutil/buffer.h b/libavutil/buffer.h
index 73b6bd0b148e6e6018845a0df928d8d20cef115a..63ab87eb720d148a7fe96e7b681f3b01fde6779f 100644 (file)
--- a/libavutil/buffer.h
+++ b/libavutil/buffer.h
@@ -25,8 +25,11 @@
 #ifndef AVUTIL_BUFFER_H
 #define AVUTIL_BUFFER_H
 
+#include <stddef.h>
 #include <stdint.h>
 
+#include "version.h"
+
 /**
  * @defgroup lavu_buffer AVBuffer
  * @ingroup lavu_data
@@ -90,7 +93,7 @@ typedef struct AVBufferRef {
     /**
      * Size of data in bytes.
      */
-    int      size;
+    size_t   size;
 } AVBufferRef;
 
 /**
@@ -98,13 +101,13 @@ typedef struct AVBufferRef {
  *
  * @return an AVBufferRef of given size or NULL when out of memory
  */
-AVBufferRef *av_buffer_alloc(int size);
+AVBufferRef *av_buffer_alloc(size_t size);
 
 /**
  * Same as av_buffer_alloc(), except the returned buffer will be initialized
  * to zero.
  */
-AVBufferRef *av_buffer_allocz(int size);
+AVBufferRef *av_buffer_allocz(size_t size);
 
 /**
  * Always treat the buffer as read-only, even when it has only one
@@ -127,7 +130,7 @@ AVBufferRef *av_buffer_allocz(int size);
  *
  * @return an AVBufferRef referring to data on success, NULL on failure.
  */
-AVBufferRef *av_buffer_create(uint8_t *data, int size,
+AVBufferRef *av_buffer_create(uint8_t *data, size_t size,
                               void (*free)(void *opaque, uint8_t *data),
                               void *opaque, int flags);
 
@@ -195,7 +198,23 @@ int av_buffer_make_writable(AVBufferRef **buf);
  * reference to it (i.e. the one passed to this function). In all other cases
  * a new buffer is allocated and the data is copied.
  */
-int av_buffer_realloc(AVBufferRef **buf, int size);
+int av_buffer_realloc(AVBufferRef **buf, size_t size);
+
+/**
+ * Ensure dst refers to the same data as src.
+ *
+ * When *dst is already equivalent to src, do nothing. Otherwise unreference dst
+ * and replace it with a new reference to src.
+ *
+ * @param dst Pointer to either a valid buffer reference or NULL. On success,
+ *            this will point to a buffer reference equivalent to src. On
+ *            failure, dst will be left untouched.
+ * @param src A buffer reference to replace dst with. May be NULL, then this
+ *            function is equivalent to av_buffer_unref(dst).
+ * @return 0 on success
+ *         AVERROR(ENOMEM) on memory allocation failure.
+ */
+int av_buffer_replace(AVBufferRef **dst, AVBufferRef *src);
 
 /**
  * @}
@@ -246,7 +265,7 @@ typedef struct AVBufferPool AVBufferPool;
  * (av_buffer_alloc()).
  * @return newly created buffer pool on success, NULL on error.
  */
-AVBufferPool *av_buffer_pool_init(int size, AVBufferRef* (*alloc)(int size));
+AVBufferPool *av_buffer_pool_init(size_t size, AVBufferRef* (*alloc)(size_t size));
 
 /**
  * Allocate and initialize a buffer pool with a more complex allocator.
@@ -254,16 +273,17 @@ AVBufferPool *av_buffer_pool_init(int size, AVBufferRef* (*alloc)(int size));
  * @param size size of each buffer in this pool
  * @param opaque arbitrary user data used by the allocator
  * @param alloc a function that will be used to allocate new buffers when the
- *              pool is empty.
+ *              pool is empty. May be NULL, then the default allocator will be
+ *              used (av_buffer_alloc()).
  * @param pool_free a function that will be called immediately before the pool
  *                  is freed. I.e. after av_buffer_pool_uninit() is called
  *                  by the caller and all the frames are returned to the pool
  *                  and freed. It is intended to uninitialize the user opaque
- *                  data.
+ *                  data. May be NULL.
  * @return newly created buffer pool on success, NULL on error.
  */
-AVBufferPool *av_buffer_pool_init2(int size, void *opaque,
-                                   AVBufferRef* (*alloc)(void *opaque, int size),
+AVBufferPool *av_buffer_pool_init2(size_t size, void *opaque,
+                                   AVBufferRef* (*alloc)(void *opaque, size_t size),
                                    void (*pool_free)(void *opaque));
 
 /**
@@ -284,6 +304,19 @@ void av_buffer_pool_uninit(AVBufferPool **pool);
  */
 AVBufferRef *av_buffer_pool_get(AVBufferPool *pool);
 
+/**
+ * Query the original opaque parameter of an allocated buffer in the pool.
+ *
+ * @param ref a buffer reference to a buffer returned by av_buffer_pool_get.
+ * @return the opaque parameter set by the buffer allocator function of the
+ *         buffer pool.
+ *
+ * @note the opaque parameter of ref is used by the buffer pool implementation,
+ * 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);
+
 /**
  * @}
  */