input: Allow demux_filter to be enabled/disabled

refs #18605

include/vlc_demux.h

@@ -323,6 +323,13 @@ enum demux_query_e
     DEMUX_NAV_POPUP,
     /** Activate disc Root Menu. Can fail */
     DEMUX_NAV_MENU,            /* res=can fail */
+    /** Enable/Disable a demux filter
+     * \warning This has limited support, and is likely to break if more than
+     * a single demux_filter is present in the chain. This is not guaranteed to
+     * work in future VLC versions, nor with all demux filters
+     */
+    DEMUX_FILTER_ENABLE,
+    DEMUX_FILTER_DISABLE
 };
 
 /*************************************************************************

src/input/demux.c

@@ -487,6 +487,8 @@ int demux_vaControlHelper( stream_t *s,
         case DEMUX_NAV_RIGHT:
         case DEMUX_NAV_POPUP:
         case DEMUX_NAV_MENU:
+        case DEMUX_FILTER_ENABLE:
+        case DEMUX_FILTER_DISABLE:
             return VLC_EGENERIC;
 
         case DEMUX_SET_TITLE:
@@ -629,3 +631,31 @@ demux_t *demux_FilterChainNew( demux_t *p_demux, const char *psz_chain )
 
     return p_demux;
 }
+
+static bool demux_filter_enable_disable( demux_t *p_demux_chain,
+                                          const char* psz_demux, bool b_enable )
+{
+    demux_t *p_demux = p_demux_chain;
+    while ( p_demux )
+    {
+        if( strcmp( module_get_name( p_demux->p_module, false ), psz_demux) == 0 ||
+            strcmp( module_get_name( p_demux->p_module, true ), psz_demux ) == 0 )
+        {
+            demux_Control( p_demux,
+                           b_enable ? DEMUX_FILTER_ENABLE : DEMUX_FILTER_DISABLE );
+            return true;
+        }
+        p_demux = p_demux->p_next;
+    }
+    return false;
+}
+
+bool demux_FilterEnable( demux_t *p_demux_chain, const char* psz_demux )
+{
+    return demux_filter_enable_disable( p_demux_chain, psz_demux, true );
+}
+
+bool demux_FilterDisable( demux_t *p_demux_chain, const char* psz_demux )
+{
+    return demux_filter_enable_disable( p_demux_chain, psz_demux, false );
+}

src/input/demux.h

@@ -41,5 +41,7 @@ int demux_GetTitle( demux_t * );
 int demux_GetSeekpoint( demux_t * );
 
 demux_t *demux_FilterChainNew( demux_t *p_demux, const char *psz_name );
+bool demux_FilterEnable( demux_t *p_demux_chain, const char* psz_demux );
+bool demux_FilterDisable( demux_t *p_demux_chain, const char* psz_demux );
 
 #endif

src/input/input.c

@@ -1871,6 +1871,16 @@ static void ControlUpdateSout( input_thread_t *p_input, const char* psz_chain )
     es_out_Control( input_priv(p_input)->p_es_out, ES_OUT_RESTART_ALL_ES );
 }
 
+static void ControlInsertDemuxFilter( input_thread_t* p_input, const char* psz_demux_chain )
+{
+    input_source_t *p_inputSource = input_priv(p_input)->master;
+    demux_t *p_filtered_demux = demux_FilterChainNew( p_inputSource->p_demux, psz_demux_chain );
+    if ( p_filtered_demux != NULL )
+        p_inputSource->p_demux = p_filtered_demux;
+    else if ( psz_demux_chain != NULL )
+        msg_Dbg(p_input, "Failed to create demux filter %s", psz_demux_chain);
+}
+
 static bool Control( input_thread_t *p_input,
                      int i_type, vlc_value_t val )
 {