[FFmpeg-devel] [PATCH v4 1/2] libavutil: create av_media_type_get_string()

[Scott Theisen]

This deprecates av_get_media_type_string() which does return NULL.

printf %s with a null pointer is undefined behavior

This also matches behavior with avcodec_get_name() which never returns NULL,
instead it returns "unknown_codec".
---
 doc/APIchanges     |  3 +++
 libavutil/avutil.h | 10 ++++++++++
 libavutil/utils.c  | 13 +++++++++++++
 3 files changed, 26 insertions(+)

diff --git a/doc/APIchanges b/doc/APIchanges
index 1a9f0a303e..53f4378a50 100644
--- a/doc/APIchanges
+++ b/doc/APIchanges
@@ -14,6 +14,9 @@ libavutil:     2021-04-27
 
 API changes, most recent first:
 
+2022-05-XX - xxxxxxxxxxx - lavu 57.19.100 - avutil.h
+  Add av_media_type_get_string() which deprecates av_get_media_type_string().
+
 2022-03-16 - xxxxxxxxxx - all libraries - version_major.h
   Add lib<name>/version_major.h as new installed headers, which only
   contain the major version number (and corresponding API deprecation
diff --git a/libavutil/avutil.h b/libavutil/avutil.h
index 4d633156d1..0f03080dcb 100644
--- a/libavutil/avutil.h
+++ b/libavutil/avutil.h
@@ -21,6 +21,8 @@
 #ifndef AVUTIL_AVUTIL_H
 #define AVUTIL_AVUTIL_H
 
+#include "attributes.h"
+
 /**
  * @file
  * @ingroup lavu
@@ -209,9 +211,17 @@ enum AVMediaType {
 /**
  * Return a string describing the media_type enum, NULL if media_type
  * is unknown.
+ *
+ * @deprecated Use av_media_type_get_string() instead.
  */
+attribute_deprecated
 const char *av_get_media_type_string(enum AVMediaType media_type);
 
+/**
+ * Return a string describing the media_type enum, never NULL.
+ */
+const char *av_media_type_get_string(enum AVMediaType media_type);
+
 /**
  * @defgroup lavu_const Constants
  * @{
diff --git a/libavutil/utils.c b/libavutil/utils.c
index 94d247bbee..5e0be8361f 100644
--- a/libavutil/utils.c
+++ b/libavutil/utils.c
@@ -37,6 +37,19 @@ const char *av_get_media_type_string(enum AVMediaType media_type)
     }
 }
 
+const char *av_media_type_get_string(enum AVMediaType media_type)
+{
+    switch (media_type) {
+    case AVMEDIA_TYPE_UNKNOWN:    return "unknown";
+    case AVMEDIA_TYPE_VIDEO:      return "video";
+    case AVMEDIA_TYPE_AUDIO:      return "audio";
+    case AVMEDIA_TYPE_DATA:       return "data";
+    case AVMEDIA_TYPE_SUBTITLE:   return "subtitle";
+    case AVMEDIA_TYPE_ATTACHMENT: return "attachment";
+    default:                      return "invalid_media_type";
+    }
+}
+
 char av_get_picture_type_char(enum AVPictureType pict_type)
 {
     switch (pict_type) {
-- 
2.34.1