dict: Change return type of av_dict_copy()

av_dict_set() could return an error, so forward it appropriately.
Signed-off-by: Vittorio Giovara <vittorio.giovara@gmail.com>

doc/APIchanges

@@ -13,6 +13,10 @@ libavutil:     2015-08-28
 
 API changes, most recent first:
 
+2015-xx-xx - xxxxxxx - lavu 55.2.0 - dict.h
+  Change return type of av_dict_copy() from void to int, so that a proper
+  error code can be reported.
+
 2015-xx-xx - xxxxxxx - lavc 57.0.0 - avcodec.h
   Change type of AVPacket.duration from int to int64_t.
 

libavutil/dict.c

@@ -186,10 +186,15 @@ void av_dict_free(AVDictionary **pm)
     av_freep(pm);
 }
 
-void av_dict_copy(AVDictionary **dst, const AVDictionary *src, int flags)
+int av_dict_copy(AVDictionary **dst, const AVDictionary *src, int flags)
 {
     AVDictionaryEntry *t = NULL;
 
-    while ((t = av_dict_get(src, "", t, AV_DICT_IGNORE_SUFFIX)))
-        av_dict_set(dst, t->key, t->value, flags);
+    while ((t = av_dict_get(src, "", t, AV_DICT_IGNORE_SUFFIX))) {
+        int ret = av_dict_set(dst, t->key, t->value, flags);
+        if (ret < 0)
+            return ret;
+    }
+
+    return 0;
 }

libavutil/dict.h

@@ -130,8 +130,10 @@ int av_dict_parse_string(AVDictionary **pm, const char *str,
  * @param src pointer to source AVDictionary struct
  * @param flags flags to use when setting entries in *dst
  * @note metadata is read using the AV_DICT_IGNORE_SUFFIX flag
+ * @return 0 on success, negative AVERROR code on failure. If dst was allocated
+ *           by this function, callers should free the associated memory.
  */
-void av_dict_copy(AVDictionary **dst, const AVDictionary *src, int flags);
+int av_dict_copy(AVDictionary **dst, const AVDictionary *src, int flags);
 
 /**
  * Free all the memory allocated for an AVDictionary struct

libavutil/version.h

@@ -54,7 +54,7 @@
  */
 
 #define LIBAVUTIL_VERSION_MAJOR 55
-#define LIBAVUTIL_VERSION_MINOR  1
+#define LIBAVUTIL_VERSION_MINOR  2
 #define LIBAVUTIL_VERSION_MICRO  0
 
 #define LIBAVUTIL_VERSION_INT   AV_VERSION_INT(LIBAVUTIL_VERSION_MAJOR, \