Add input resource support to the LibVLC Media Player

This change allows for smoother transitioning between playlist items by
not having to recreate the related video/audio resources from scratch on
every item switch. This problem was very apparent in fullscreen mode
when the current display would close out showing the OS background and
then go back to fullscreen before playing the next item.
Signed-off-by: Rémi Denis-Courmont <remi@remlab.net>

include/vlc_input.h

@@ -613,4 +613,18 @@ VLC_EXPORT( void, input_SplitMRL, ( const char **ppsz_access, const char **ppsz_
  */
 VLC_EXPORT( char *, input_CreateFilename, ( vlc_object_t *, const char *psz_path, const char *psz_prefix, const char *psz_extension ) );
 
+/**
+ * This function detaches resources from a dead input.
+ *
+ * It MUST be called on a dead input (p_input->b_dead true) otherwise
+ * it will assert.
+ * It does not support concurrent calls.
+ */
+VLC_EXPORT(input_resource_t *, input_DetachResource, ( input_thread_t * ) );
+
+/**
+ * This function releases the input resource.
+ */
+VLC_EXPORT(void, input_resource_Delete, ( input_resource_t * ) );
+
 #endif

src/control/media_player.c

@@ -82,8 +82,14 @@ static void release_input_thread( libvlc_media_player_t *p_mi, bool b_input_abor
 
     /* We owned this one */
     input_Stop( p_input_thread, b_input_abort );
+
     vlc_thread_join( p_input_thread );
 
+    assert( p_mi->p_input_resource == NULL );
+    assert( p_input_thread->b_dead );
+    /* Store the input resource for future use. */
+    p_mi->p_input_resource = input_DetachResource( p_input_thread );
+
     var_Destroy( p_input_thread, "drawable-hwnd" );
     var_Destroy( p_input_thread, "drawable-xid" );
     var_Destroy( p_input_thread, "drawable-agl" );
@@ -288,6 +294,7 @@ libvlc_media_player_new( libvlc_instance_t * p_libvlc_instance,
     p_mi->drawable.nsobject = NULL;
     p_mi->p_libvlc_instance = p_libvlc_instance;
     p_mi->p_input_thread = NULL;
+    p_mi->p_input_resource = NULL;
     p_mi->i_refcount = 1;
     vlc_mutex_init( &p_mi->object_lock );
     p_mi->p_event_manager = libvlc_event_manager_new( p_mi,
@@ -382,9 +389,15 @@ static void libvlc_media_player_destroy( libvlc_media_player_t *p_mi )
     var_DelCallback( p_mi->p_libvlc_instance->p_libvlc_int,
                      "vout-snapshottaken", SnapshotTakenCallback, p_mi );
 
-    /* Realease the input thread */
+    /* Release the input thread */
     release_input_thread( p_mi, true );
 
+    if( p_mi->p_input_resource )
+    {
+        input_resource_Delete( p_mi->p_input_resource );
+        p_mi->p_input_resource = NULL;    
+    }
+
     libvlc_event_manager_release( p_mi->p_event_manager );
     libvlc_media_release( p_mi->p_md );
     vlc_mutex_destroy( &p_mi->object_lock );
@@ -553,7 +566,7 @@ void libvlc_media_player_play( libvlc_media_player_t *p_mi,
     }
 
     p_mi->p_input_thread = input_Create( p_mi->p_libvlc_instance->p_libvlc_int,
-                                         p_mi->p_md->p_input_item, NULL, NULL );
+                                         p_mi->p_md->p_input_item, NULL, p_mi->p_input_resource );
 
     if( !p_mi->p_input_thread )
     {
@@ -561,6 +574,7 @@ void libvlc_media_player_play( libvlc_media_player_t *p_mi,
         return;
     }
 
+    p_mi->p_input_resource = NULL;
     p_input_thread = p_mi->p_input_thread;
 
     var_Create( p_input_thread, "drawable-agl", VLC_VAR_INTEGER );

src/control/media_player_internal.h

@@ -32,12 +32,14 @@
 #include <vlc/vlc.h>
 #include <vlc/libvlc_structures.h>
 #include <vlc/libvlc_media.h>
+#include <vlc_input.h>
 
 struct libvlc_media_player_t
 {
     int                i_refcount;
     vlc_mutex_t        object_lock;
     input_thread_t *   p_input_thread;
+	input_resource_t * p_input_resource;
     struct libvlc_instance_t * p_libvlc_instance; /* Parent instance */
     libvlc_media_t * p_md; /* current media descriptor */
     libvlc_event_manager_t * p_event_manager;

src/input/input_interface.h

@@ -46,11 +46,6 @@ int input_Preparse( vlc_object_t *, input_item_t * );
  * FIXME it should NOT be defined here or not coded in misc/stats.c */
 input_stats_t *stats_NewInputStats( input_thread_t *p_input );
 
-/**
- * This function releases an input_resource_t and all associated resources.
- */
-void input_resource_Delete( input_resource_t * );
-
 /**
  * This function deletes the current sout in the resources.
  */
@@ -70,15 +65,6 @@ bool input_resource_HasVout( input_resource_t *p_resource );
 
 /* input.c */
 
-/**
- * This function detaches resources from a dead input.
- *
- * It MUST be called on a dead input (p_input->b_dead true) otherwise
- * it will assert.
- * It does not support concurrent calls.
- */
-input_resource_t *input_DetachResource( input_thread_t * );
-
 /* */
 typedef enum
 {

src/libvlccore.sym

@@ -181,6 +181,7 @@ input_CreateFilename
 input_DecoderDecode
 input_DecoderDelete
 input_DecoderNew
+input_DetachResource
 input_GetItem
 input_item_AddInfo
 input_item_AddOption
@@ -206,6 +207,7 @@ input_item_SetURI
 input_item_WriteMeta
 input_MetaTypeToLocalizedString
 __input_Read
+input_resource_Delete
 input_SplitMRL
 input_Start
 input_Stop