lavu/opt: add AV_OPT_FLAG_DEPRECATED

doc/APIchanges

@@ -15,6 +15,9 @@ libavutil:     2017-10-21
 
 API changes, most recent first:
 
+2018-04-xx - xxxxxxxxxx - lavu 56.17.100 - opt.h
+  Add AV_OPT_FLAG_DEPRECATED.
+
 2018-04-xx - xxxxxxxxxx - lavu 56.16.100 - threadmessage.h
   Add av_thread_message_queue_nb_elems().
 

libavutil/opt.c

@@ -463,6 +463,9 @@ int av_opt_set(void *obj, const char *name, const char *val, int search_flags)
     if (o->flags & AV_OPT_FLAG_READONLY)
         return AVERROR(EINVAL);
 
+    if (o->flags & AV_OPT_FLAG_DEPRECATED)
+        av_log(obj, AV_LOG_WARNING, "The \"%s\" option is deprecated: %s\n", name, o->help);
+
     dst = ((uint8_t *)target_obj) + o->offset;
     switch (o->type) {
     case AV_OPT_TYPE_BOOL:
@@ -759,6 +762,9 @@ int av_opt_get(void *obj, const char *name, int search_flags, uint8_t **out_val)
     if (!o || !target_obj || (o->offset<=0 && o->type != AV_OPT_TYPE_CONST))
         return AVERROR_OPTION_NOT_FOUND;
 
+    if (o->flags & AV_OPT_FLAG_DEPRECATED)
+        av_log(obj, AV_LOG_WARNING, "The \"%s\" option is deprecated: %s\n", name, o->help);
+
     dst = (uint8_t *)target_obj + o->offset;
 
     buf[0] = 0;

libavutil/opt.h

@@ -289,6 +289,7 @@ typedef struct AVOption {
 #define AV_OPT_FLAG_READONLY        128
 #define AV_OPT_FLAG_BSF_PARAM       (1<<8) ///< a generic parameter which can be set by the user for bit stream filtering
 #define AV_OPT_FLAG_FILTERING_PARAM (1<<16) ///< a generic parameter which can be set by the user for filtering
+#define AV_OPT_FLAG_DEPRECATED      (1<<17) ///< set if option is deprecated, users should refer to AVOption.help text for more information
 //FIXME think about enc-audio, ... style flags
 
     /**

libavutil/version.h

@@ -79,7 +79,7 @@
  */
 
 #define LIBAVUTIL_VERSION_MAJOR  56
-#define LIBAVUTIL_VERSION_MINOR  16
+#define LIBAVUTIL_VERSION_MINOR  17
 #define LIBAVUTIL_VERSION_MICRO 100
 
 #define LIBAVUTIL_VERSION_INT   AV_VERSION_INT(LIBAVUTIL_VERSION_MAJOR, \