[mutter] ScreenCast: Pass PipeWire stream node ID directly

[Jonas Ådahl <jadahl src gnome org>]

commit 53175e87884a59beb5f90cda1458af5d15b29c4d
Author: Jonas Ådahl <jadahl gmail com>
Date:   Wed Jun 28 15:17:32 2017 +0800

    ScreenCast: Pass PipeWire stream node ID directly
    
    As of commit 5f5ef3de2cdc816dab82cb7eb5d7171bee0ad2c5 in pipewire the
    stream creator can find out the node ID of the stream it created.
    
    So instead of using a special purpose entry to the info property box to
    let the application discover stream by monitoring added nodes searching
    for the given special purpose entry, just pass the node directly.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=784199

 src/backends/meta-screen-cast-monitor-stream-src.c |    6 +---
 src/backends/meta-screen-cast-monitor-stream-src.h |    1 -
 src/backends/meta-screen-cast-monitor-stream.c     |    2 -
 src/backends/meta-screen-cast-stream-src.c         |   34 +++++++++-----------
 src/backends/meta-screen-cast-stream.c             |   21 +++++++-----
 src/backends/meta-screen-cast-stream.h             |    1 -
 src/org.gnome.Mutter.ScreenCast.xml                |    2 +-
 7 files changed, 29 insertions(+), 38 deletions(-)
---
diff --git a/src/backends/meta-screen-cast-monitor-stream-src.c 
b/src/backends/meta-screen-cast-monitor-stream-src.c
index e5a681b..382d7d4 100644
--- a/src/backends/meta-screen-cast-monitor-stream-src.c
+++ b/src/backends/meta-screen-cast-monitor-stream-src.c
@@ -147,13 +147,9 @@ meta_screen_cast_monitor_stream_src_record_frame (MetaScreenCastStreamSrc *src,
 
 MetaScreenCastMonitorStreamSrc *
 meta_screen_cast_monitor_stream_src_new (MetaScreenCastMonitorStream  *monitor_stream,
-                                         const char                   *stream_id,
                                          GError                      **error)
 {
-  return g_initable_new (META_TYPE_SCREEN_CAST_MONITOR_STREAM_SRC,
-                         NULL,
-                         error,
-                         "stream-id", stream_id,
+  return g_initable_new (META_TYPE_SCREEN_CAST_MONITOR_STREAM_SRC, NULL, error,
                          "stream", monitor_stream,
                          NULL);
 }
diff --git a/src/backends/meta-screen-cast-monitor-stream-src.h 
b/src/backends/meta-screen-cast-monitor-stream-src.h
index 26a0d91..7417a81 100644
--- a/src/backends/meta-screen-cast-monitor-stream-src.h
+++ b/src/backends/meta-screen-cast-monitor-stream-src.h
@@ -35,7 +35,6 @@ G_DECLARE_FINAL_TYPE (MetaScreenCastMonitorStreamSrc,
                       MetaScreenCastStreamSrc)
 
 MetaScreenCastMonitorStreamSrc * meta_screen_cast_monitor_stream_src_new (MetaScreenCastMonitorStream 
*monitor_stream,
-                                                                          const char                  
*stream_id,
                                                                           GError                     
**error);
 
 #endif /* META_SCREEN_CAST_MONITOR_STREAM_SRC_H */
diff --git a/src/backends/meta-screen-cast-monitor-stream.c b/src/backends/meta-screen-cast-monitor-stream.c
index e97a173..1630b8e 100644
--- a/src/backends/meta-screen-cast-monitor-stream.c
+++ b/src/backends/meta-screen-cast-monitor-stream.c
@@ -135,7 +135,6 @@ meta_screen_cast_monitor_stream_new (GDBusConnection     *connection,
 
 static MetaScreenCastStreamSrc *
 meta_screen_cast_monitor_stream_create_src (MetaScreenCastStream  *stream,
-                                            const char            *stream_id,
                                             GError               **error)
 {
   MetaScreenCastMonitorStream *monitor_stream =
@@ -143,7 +142,6 @@ meta_screen_cast_monitor_stream_create_src (MetaScreenCastStream  *stream,
   MetaScreenCastMonitorStreamSrc *monitor_stream_src;
 
   monitor_stream_src = meta_screen_cast_monitor_stream_src_new (monitor_stream,
-                                                                stream_id,
                                                                 error);
   if (!monitor_stream_src)
     return NULL;
diff --git a/src/backends/meta-screen-cast-stream-src.c b/src/backends/meta-screen-cast-stream-src.c
index 9204635..7f82177 100644
--- a/src/backends/meta-screen-cast-stream-src.c
+++ b/src/backends/meta-screen-cast-stream-src.c
@@ -47,11 +47,11 @@ enum
   PROP_0,
 
   PROP_STREAM,
-  PROP_STREAM_ID,
 };
 
 enum
 {
+  READY,
   CLOSED,
 
   N_SIGNALS
@@ -81,7 +81,6 @@ typedef struct _MetaPipeWireSource
 typedef struct _MetaScreenCastStreamSrcPrivate
 {
   MetaScreenCastStream *stream;
-  char *stream_id;
 
   struct pw_core *pipewire_core;
   struct pw_remote *pipewire_remote;
@@ -243,6 +242,9 @@ on_stream_state_changed (void                 *data,
                          const char           *error_message)
 {
   MetaScreenCastStreamSrc *src = data;
+  MetaScreenCastStreamSrcPrivate *priv =
+    meta_screen_cast_stream_src_get_instance_private (src);
+  uint32_t node_id;
 
   switch (state)
     {
@@ -250,9 +252,12 @@ on_stream_state_changed (void                 *data,
       g_warning ("pipewire stream error: %s", error_message);
       meta_screen_cast_stream_src_notify_closed (src);
       break;
+    case PW_STREAM_STATE_CONFIGURE:
+      node_id = pw_stream_get_node_id (priv->pipewire_stream);
+      g_signal_emit (src, signals[READY], 0, (unsigned int) node_id);
+      break;
     case PW_STREAM_STATE_UNCONNECTED:
     case PW_STREAM_STATE_CONNECTING:
-    case PW_STREAM_STATE_CONFIGURE:
     case PW_STREAM_STATE_READY:
     case PW_STREAM_STATE_PAUSED:
       if (meta_screen_cast_stream_src_is_enabled (src))
@@ -585,7 +590,6 @@ meta_screen_cast_stream_src_finalize (GObject *object)
   pw_remote_destroy (priv->pipewire_remote);
   pw_core_destroy (priv->pipewire_core);
   g_source_destroy (&priv->pipewire_source->base);
-  g_clear_pointer (&priv->stream_id, g_free);
 
   G_OBJECT_CLASS (meta_screen_cast_stream_src_parent_class)->finalize (object);
 }
@@ -605,9 +609,6 @@ meta_screen_cast_stream_src_set_property (GObject      *object,
     case PROP_STREAM:
       priv->stream = g_value_get_object (value);
       break;;
-    case PROP_STREAM_ID:
-      priv->stream_id = g_strdup (g_value_get_string (value));
-      break;
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
     }
@@ -628,9 +629,6 @@ meta_screen_cast_stream_src_get_property (GObject    *object,
     case PROP_STREAM:
       g_value_set_object (value, priv->stream);
       break;
-    case PROP_STREAM_ID:
-      g_value_set_string (value, priv->stream_id);
-      break;
     default:
       G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
     }
@@ -659,16 +657,14 @@ meta_screen_cast_stream_src_class_init (MetaScreenCastStreamSrcClass *klass)
                                                         G_PARAM_READWRITE |
                                                         G_PARAM_CONSTRUCT_ONLY |
                                                         G_PARAM_STATIC_STRINGS));
-  g_object_class_install_property (object_class,
-                                   PROP_STREAM_ID,
-                                   g_param_spec_string ("stream-id",
-                                                        "stream-id",
-                                                        "Unique stream ID",
-                                                        NULL,
-                                                        G_PARAM_READWRITE |
-                                                        G_PARAM_CONSTRUCT_ONLY |
-                                                        G_PARAM_STATIC_STRINGS));
 
+  signals[READY] = g_signal_new ("ready",
+                                 G_TYPE_FROM_CLASS (klass),
+                                 G_SIGNAL_RUN_LAST,
+                                 0,
+                                 NULL, NULL, NULL,
+                                 G_TYPE_NONE, 1,
+                                 G_TYPE_UINT);
   signals[CLOSED] = g_signal_new ("closed",
                                   G_TYPE_FROM_CLASS (klass),
                                   G_SIGNAL_RUN_LAST,
diff --git a/src/backends/meta-screen-cast-stream.c b/src/backends/meta-screen-cast-stream.c
index 047f287..1a8ef6b 100644
--- a/src/backends/meta-screen-cast-stream.c
+++ b/src/backends/meta-screen-cast-stream.c
@@ -62,11 +62,9 @@ G_DEFINE_TYPE_WITH_CODE (MetaScreenCastStream,
 
 static MetaScreenCastStreamSrc *
 meta_screen_cast_stream_create_src (MetaScreenCastStream  *stream,
-                                    const char            *stream_id,
                                     GError               **error)
 {
   return META_SCREEN_CAST_STREAM_GET_CLASS (stream)->create_src (stream,
-                                                                 stream_id,
                                                                  error);
 }
 
@@ -81,27 +79,32 @@ on_stream_src_closed (MetaScreenCastStreamSrc *src,
     meta_screen_cast_stream_close (stream);
 }
 
+static void
+on_stream_src_ready (MetaScreenCastStreamSrc *src,
+                     uint32_t                 node_id,
+                     MetaScreenCastStream    *stream)
+{
+  MetaDBusScreenCastStream *skeleton = META_DBUS_SCREEN_CAST_STREAM (stream);
+
+  meta_dbus_screen_cast_stream_emit_pipewire_stream_added (skeleton, node_id);
+}
+
 gboolean
 meta_screen_cast_stream_start (MetaScreenCastStream  *stream,
                                GError               **error)
 {
-  MetaDBusScreenCastStream *skeleton = META_DBUS_SCREEN_CAST_STREAM (stream);
   MetaScreenCastStreamPrivate *priv =
     meta_screen_cast_stream_get_instance_private (stream);
-  g_autofree char *stream_id = NULL;
   MetaScreenCastStreamSrc *src;
-  static unsigned int global_stream_id = 0;
 
-  stream_id = g_strdup_printf ("%u", ++global_stream_id);
-  src = meta_screen_cast_stream_create_src (stream, stream_id, error);
+  src = meta_screen_cast_stream_create_src (stream, error);
   if (!src)
     return FALSE;
 
   priv->src = src;
+  g_signal_connect (src, "ready", G_CALLBACK (on_stream_src_ready), stream);
   g_signal_connect (src, "closed", G_CALLBACK (on_stream_src_closed), stream);
 
-  meta_dbus_screen_cast_stream_emit_pipewire_stream_added (skeleton, stream_id);
-
   return TRUE;
 }
 
diff --git a/src/backends/meta-screen-cast-stream.h b/src/backends/meta-screen-cast-stream.h
index b8366ae..1ed1a83 100644
--- a/src/backends/meta-screen-cast-stream.h
+++ b/src/backends/meta-screen-cast-stream.h
@@ -38,7 +38,6 @@ struct _MetaScreenCastStreamClass
   MetaDBusScreenCastStreamSkeletonClass parent_class;
 
   MetaScreenCastStreamSrc * (* create_src) (MetaScreenCastStream *stream,
-                                            const char           *stream_id,
                                             GError              **error);
 };
 
diff --git a/src/org.gnome.Mutter.ScreenCast.xml b/src/org.gnome.Mutter.ScreenCast.xml
index bab3fea..f774091 100644
--- a/src/org.gnome.Mutter.ScreenCast.xml
+++ b/src/org.gnome.Mutter.ScreenCast.xml
@@ -99,7 +99,7 @@
     -->
     <signal name="PipeWireStreamAdded">
       <annotation name="org.gtk.GDBus.C.Name" value="pipewire-stream-added"/>
-      <arg name="stream_id" type="s" direction="out" />
+      <arg name="node_id" type="u" direction="out" />
     </signal>
 
   </interface>