Fix dash crash if format not supported. v5.0.177 v6.0.73 (#3795)

Fix the issue of DASH crashing when audio/video formats are not
supported.

---------

Co-authored-by: Haibo Chen <495810242@qq.com>

trunk/doc/CHANGELOG.md

@@ -7,6 +7,7 @@ The changelog for SRS.
 <a name="v6-changes"></a>
 
 ## SRS 6.0 Changelog
+* v6.0, 2023-09-07, Merge [#3795](https://github.com/ossrs/srs/pull/3795): Fix dash crash if format not supported. v6.0.73 (#3795)
 * v6.0, 2023-08-30, Merge [#3776](https://github.com/ossrs/srs/pull/3776): Compile: Add aarch64 to the conditions of use of the cbrt function. v6.0.72 (#3776)
 * v6.0, 2023-08-30, Merge [#3779](https://github.com/ossrs/srs/pull/3779): Support HTTP-API for fetching reload result. v6.0.71 (#3779)
 * v6.0, 2023-08-28, Merge [#3503](https://github.com/ossrs/srs/pull/3503): SrsContextId assignment can be improved without create a duplicated one. v6.0.70 (#3503)
@@ -84,6 +85,7 @@ The changelog for SRS.
 <a name="v5-changes"></a>
 
 ## SRS 5.0 Changelog
+* v5.0, 2023-09-07, Merge [#3795](https://github.com/ossrs/srs/pull/3795): Fix dash crash if format not supported. v5.0.177 (#3795)
 * v5.0, 2023-08-30, Merge [#3779](https://github.com/ossrs/srs/pull/3779): Support HTTP-API for fetching reload result. v5.0.176 (#3779)
 * v5.0, 2023-08-28, Merge [#3503](https://github.com/ossrs/srs/pull/3503): SrsContextId assignment can be improved without create a duplicated one. v5.0.175 (#3503)
 * v5.0, 2023-08-28, Merge [#3781](https://github.com/ossrs/srs/pull/3781): HLS: Fix on_hls and hls_dispose critical zone issue. v5.0.174 (#3781)

trunk/src/app/srs_app_dash.cpp

@@ -619,7 +619,7 @@ srs_error_t SrsDashController::refresh_mpd(SrsFormat* format)
     srs_error_t err = srs_success;
     
     // TODO: FIXME: Support pure audio streaming.
-    if (!format->acodec || !format->vcodec) {
+    if (!format || !format->acodec || !format->vcodec) {
         return err;
     }
     

trunk/src/core/srs_core_version5.hpp

@@ -9,6 +9,6 @@
 
 #define VERSION_MAJOR       5
 #define VERSION_MINOR       0
-#define VERSION_REVISION    176
+#define VERSION_REVISION    177
 
 #endif

trunk/src/core/srs_core_version6.hpp

@@ -9,6 +9,6 @@
 
 #define VERSION_MAJOR       6
 #define VERSION_MINOR       0
-#define VERSION_REVISION    72
+#define VERSION_REVISION    73
 
 #endif