clapper-app: Create pipeline preview file async

src/bin/clapper-app/clapper-app-application.c

@@ -41,6 +41,7 @@ struct _ClapperAppApplication
   GtkApplication parent;
 
   GSettings *settings;
+  GCancellable *cancellable;
 
   gboolean need_init_state;
 };
@@ -61,6 +62,12 @@ struct ClapperPluginData
   struct ClapperPluginFeatureData features[10];
 };
 
+typedef struct
+{
+  ClapperAppApplication *app;
+  guint id;
+} ClapperAppWindowData;
+
 typedef struct
 {
   const gchar *action;
@@ -396,7 +403,7 @@ show_info (GSimpleAction *action, GVariant *param, gpointer user_data)
 }
 
 static void
-_show_pipeline_cb (GtkFileLauncher *launcher,
+_launch_pipeline_cb (GtkFileLauncher *launcher,
     GAsyncResult *res, gpointer user_data G_GNUC_UNUSED)
 {
   GError *error = NULL;
@@ -411,14 +418,52 @@ _show_pipeline_cb (GtkFileLauncher *launcher,
 }
 
 static void
-show_pipeline (GSimpleAction *action, GVariant *param, gpointer user_data)
+_show_pipeline_cb (GObject *source G_GNUC_UNUSED,
+    GAsyncResult *res, ClapperAppWindowData *win_data)
 {
-  GtkApplication *gtk_app = GTK_APPLICATION (user_data);
+  GTask *task = G_TASK (res);
   GtkWindow *window;
-  GtkFileLauncher *launcher;
   GFile *svg_file;
   GError *error = NULL;
 
+  svg_file = (GFile *) g_task_propagate_pointer (task, &error);
+
+  if (error) {
+    if (error->domain != G_IO_ERROR || error->code != G_IO_ERROR_CANCELLED) {
+      GST_ERROR ("Could not create pipeline graph file, reason: %s",
+          GST_STR_NULL (error->message));
+    }
+    g_error_free (error);
+    g_free (win_data);
+
+    return;
+  }
+
+  if ((window = gtk_application_get_window_by_id (
+      GTK_APPLICATION (win_data->app), win_data->id))) {
+    GtkFileLauncher *launcher = gtk_file_launcher_new (svg_file);
+
+#if GTK_CHECK_VERSION(4,12,0)
+    gtk_file_launcher_set_always_ask (launcher, TRUE);
+#endif
+
+    gtk_file_launcher_launch (launcher, window, NULL,
+        (GAsyncReadyCallback) _launch_pipeline_cb, NULL);
+    g_object_unref (launcher);
+  }
+
+  g_object_unref (svg_file);
+  g_free (win_data);
+}
+
+static void
+show_pipeline (GSimpleAction *action, GVariant *param, gpointer user_data)
+{
+  ClapperAppApplication *self = CLAPPER_APP_APPLICATION_CAST (user_data);
+  GtkApplication *gtk_app = GTK_APPLICATION (self);
+  GtkWindow *window;
+  ClapperAppWindowData *win_data;
+
   window = gtk_application_get_active_window (gtk_app);
 
   while (window && !CLAPPER_APP_IS_WINDOW (window))
@@ -427,25 +472,19 @@ show_pipeline (GSimpleAction *action, GVariant *param, gpointer user_data)
   if (G_UNLIKELY (window == NULL))
     return;
 
-  if (!(svg_file = clapper_app_utils_create_pipeline_svg_file (
-      clapper_app_window_get_player (CLAPPER_APP_WINDOW (window)), &error))) {
-    GST_ERROR ("Could not create pipeline graph file, reason: %s",
-        GST_STR_NULL (error->message));
-    g_error_free (error);
-
-    return;
+  if (self->cancellable) {
+    g_cancellable_cancel (self->cancellable);
+    g_object_unref (self->cancellable);
   }
+  self->cancellable = g_cancellable_new ();
 
-  launcher = gtk_file_launcher_new (svg_file);
-  g_object_unref (svg_file);
+  win_data = g_new (ClapperAppWindowData, 1);
+  win_data->app = self;
+  win_data->id = gtk_application_window_get_id (GTK_APPLICATION_WINDOW (window));
 
-#if GTK_CHECK_VERSION(4,12,0)
-  gtk_file_launcher_set_always_ask (launcher, TRUE);
-#endif
-
-  gtk_file_launcher_launch (launcher, window, NULL,
-      (GAsyncReadyCallback) _show_pipeline_cb, NULL);
-  g_object_unref (launcher);
+  clapper_app_utils_create_pipeline_svg_file_async (
+      clapper_app_window_get_player (CLAPPER_APP_WINDOW (window)),
+      self->cancellable, (GAsyncReadyCallback) _show_pipeline_cb, win_data);
 }
 
 static void
@@ -809,6 +848,19 @@ clapper_app_application_constructed (GObject *object)
   G_OBJECT_CLASS (parent_class)->constructed (object);
 }
 
+static void
+clapper_app_application_dispose (GObject *object)
+{
+  ClapperAppApplication *self = CLAPPER_APP_APPLICATION_CAST (object);
+
+  if (self->cancellable) {
+    g_cancellable_cancel (self->cancellable);
+    g_clear_object (&self->cancellable);
+  }
+
+  G_OBJECT_CLASS (parent_class)->dispose (object);
+}
+
 static void
 clapper_app_application_finalize (GObject *object)
 {
@@ -832,6 +884,7 @@ clapper_app_application_class_init (ClapperAppApplicationClass *klass)
       "Clapper App Application");
 
   gobject_class->constructed = clapper_app_application_constructed;
+  gobject_class->dispose = clapper_app_application_dispose;
   gobject_class->finalize = clapper_app_application_finalize;
 
   gtk_application_class->window_removed = clapper_app_application_window_removed;

src/bin/clapper-app/clapper-app-application.h

@@ -19,6 +19,7 @@
 
 #include <glib.h>
 #include <glib-object.h>
+#include <gio/gio.h>
 #include <gtk/gtk.h>
 
 G_BEGIN_DECLS

src/bin/clapper-app/clapper-app-utils.c

@@ -548,42 +548,42 @@ _get_tmp_dir (const gchar *subdir)
 
 #ifdef HAVE_GRAPHVIZ
 static GFile *
-_create_tmp_subdir (const gchar *subdir)
+_create_tmp_subdir (const gchar *subdir, GCancellable *cancellable, GError **error)
 {
   GFile *tmp_dir;
-  GError *error = NULL;
+  GError *my_error = NULL;
 
   tmp_dir = _get_tmp_dir (subdir);
 
-  if (!g_file_make_directory_with_parents (tmp_dir, NULL, &error)) {
-    if (error->domain != G_IO_ERROR || error->code != G_IO_ERROR_EXISTS) {
-      GST_ERROR ("Could not create temp dir, reason: %s",
-          GST_STR_NULL (error->message));
+  if (!g_file_make_directory_with_parents (tmp_dir, cancellable, &my_error)) {
+    if (my_error->domain != G_IO_ERROR || my_error->code != G_IO_ERROR_EXISTS) {
+      *error = g_error_copy (my_error);
       g_clear_object (&tmp_dir); // return NULL
     }
-    g_error_free (error);
+    g_error_free (my_error);
   }
 
   return tmp_dir;
 }
 #endif
 
-GFile *
-clapper_app_utils_create_pipeline_svg_file (ClapperPlayer *player, GError **error)
+static void
+_create_pipeline_svg_file_in_thread (GTask *task, GObject *source G_GNUC_UNUSED,
+    ClapperPlayer *player, GCancellable *cancellable)
 {
   GFile *tmp_file = NULL;
+  GError *error = NULL;
 
 #ifdef HAVE_GRAPHVIZ
   GFile *tmp_subdir;
   Agraph_t *graph;
   GVC_t *gvc;
-  gchar *path, *template, *dot_data, *img_data = NULL;
+  gchar *path, *template = NULL, *dot_data = NULL, *img_data = NULL;
   gint fd;
   guint size = 0;
 
-  tmp_subdir = _create_tmp_subdir ("pipelines");
-  if (G_UNLIKELY (tmp_subdir == NULL))
-    return NULL;
+  if (!(tmp_subdir = _create_tmp_subdir ("pipelines", cancellable, &error)))
+    goto finish;
 
   path = g_file_get_path (tmp_subdir);
   g_object_unref (tmp_subdir);
@@ -594,14 +594,16 @@ clapper_app_utils_create_pipeline_svg_file (ClapperPlayer *player, GError **erro
   fd = g_mkstemp (template); // Modifies template to actual filename
 
   if (G_UNLIKELY (fd == -1)) {
-    g_set_error (error, G_FILE_ERROR, G_FILE_ERROR_FAILED,
+    g_set_error (&error, G_FILE_ERROR, G_FILE_ERROR_FAILED,
         "Could not open temp file for writing");
-    g_free (template);
-
-    return NULL;
+    goto finish;
   }
 
   dot_data = clapper_player_make_pipeline_graph (player, GST_DEBUG_GRAPH_SHOW_ALL);
+
+  if (g_cancellable_is_cancelled (cancellable))
+    goto close_and_finish;
+
   graph = agmemread (dot_data);
 
   gvc = gvContext ();
@@ -610,27 +612,48 @@ clapper_app_utils_create_pipeline_svg_file (ClapperPlayer *player, GError **erro
 
   agclose (graph);
   gvFreeContext (gvc);
-  g_free (dot_data);
+
+  if (g_cancellable_is_cancelled (cancellable))
+    goto close_and_finish;
 
   if (write (fd, img_data, size) != -1) {
     tmp_file = g_file_new_for_path (template);
   } else {
-    g_set_error (error, G_FILE_ERROR, G_FILE_ERROR_FAILED,
+    g_set_error (&error, G_FILE_ERROR, G_FILE_ERROR_FAILED,
         "Could not write data to temp file");
   }
 
+close_and_finish:
   /* Always close the file IO */
   if (G_UNLIKELY (close (fd) == -1))
     GST_ERROR ("Could not close temp file!");
 
-  g_free (img_data);
+finish:
   g_free (template);
+  g_free (dot_data);
+  g_free (img_data);
 #else
-  g_set_error (error, G_FILE_ERROR, G_FILE_ERROR_FAILED,
+  g_set_error (&error, G_FILE_ERROR, G_FILE_ERROR_FAILED,
       "Cannot create graph file when compiled without Graphviz");
 #endif
 
-  return tmp_file;
+  if (tmp_file)
+    g_task_return_pointer (task, tmp_file, (GDestroyNotify) g_object_unref);
+  else
+    g_task_return_error (task, error);
+}
+
+void
+clapper_app_utils_create_pipeline_svg_file_async (ClapperPlayer *player,
+    GCancellable *cancellable, GAsyncReadyCallback callback, gpointer user_data)
+{
+  GTask *task;
+
+  task = g_task_new (NULL, cancellable, callback, user_data);
+  g_task_set_task_data (task, gst_object_ref (player), (GDestroyNotify) gst_object_unref);
+  g_task_run_in_thread (task, (GTaskThreadFunc) _create_pipeline_svg_file_in_thread);
+
+  g_object_unref (task);
 }
 
 static gboolean

src/bin/clapper-app/clapper-app-utils.h

@@ -85,7 +85,7 @@ G_GNUC_INTERNAL
 GstElement * clapper_app_utils_make_element (const gchar *string);
 
 G_GNUC_INTERNAL
-GFile * clapper_app_utils_create_pipeline_svg_file (ClapperPlayer *player, GError **error);
+void clapper_app_utils_create_pipeline_svg_file_async (ClapperPlayer *player, GCancellable *cancellable, GAsyncReadyCallback callback, gpointer user_data);
 
 G_GNUC_INTERNAL
 void clapper_app_utils_delete_tmp_dir (void);