[gnome-shell] Add Main.currentTime(), to get the correct current-event-time

[Dan Winship <danw src gnome org>]

commit 110ef17e2d7fd6bbdd3dc3b4f6171713fca5c260
Author: Dan Winship <danw gnome org>
Date:   Wed Sep 23 10:13:36 2009 -0400

    Add Main.currentTime(), to get the correct current-event-time
    
    https://bugzilla.gnome.org/show_bug.cgi?id=590563

 js/ui/appDisplay.js |    8 ++++----
 js/ui/appIcon.js    |    2 +-
 js/ui/main.js       |   43 ++++++++++++++++++++++++++++++++-----------
 js/ui/overview.js   |    2 +-
 4 files changed, 38 insertions(+), 17 deletions(-)
---
diff --git a/js/ui/appDisplay.js b/js/ui/appDisplay.js
index ea02da1..9fff7cb 100644
--- a/js/ui/appDisplay.js
+++ b/js/ui/appDisplay.js
@@ -60,7 +60,7 @@ AppDisplayItem.prototype = {
         let windows = Shell.AppMonitor.get_default().get_windows_for_app(this._appInfo.get_id());
         if (windows.length > 0) {
             let mostRecentWindow = windows[0];
-            Main.overview.activateWindow(mostRecentWindow, Clutter.get_current_event_time());
+            Main.overview.activateWindow(mostRecentWindow, Main.currentTime());
         } else {
             this._appInfo.launch();
         }
@@ -486,7 +486,7 @@ BaseWellItem.prototype = {
                 if (this.actor.pressed && this._dragStartX != null) {
                     this.actor.fake_release();
                     this._draggable.startDrag(this._dragStartX, this._dragStartY,
-                                              Clutter.get_current_event_time());
+                                              Main.currentTime());
                 } else {
                     this._dragStartX = null;
                     this._dragStartY = null;
@@ -547,7 +547,7 @@ RunningWellItem.prototype = {
     activateMostRecentWindow: function () {
         // The _get_windows_for_app sorts them for us
         let mostRecentWindow = this.windows[0];
-        Main.overview.activateWindow(mostRecentWindow, Clutter.get_current_event_time());
+        Main.overview.activateWindow(mostRecentWindow, Main.currentTime());
     },
 
     highlightWindow: function(metaWindow) {
@@ -557,7 +557,7 @@ RunningWellItem.prototype = {
     activateWindow: function(metaWindow) {
         if (metaWindow) {
             this._didActivateWindow = true;
-            Main.overview.activateWindow(metaWindow, Clutter.get_current_event_time());
+            Main.overview.activateWindow(metaWindow, Main.currentTime());
         } else
             Main.overview.hide();
     },
diff --git a/js/ui/appIcon.js b/js/ui/appIcon.js
index 59dcf4a..6a74e7d 100644
--- a/js/ui/appIcon.js
+++ b/js/ui/appIcon.js
@@ -447,7 +447,7 @@ AppIconMenu.prototype = {
 
         this._redisplay();
 
-        this._windowContainer.popup(0, Clutter.get_current_event_time());
+        this._windowContainer.popup(0, Main.currentTime());
 
         this.emit('popup', true);
 
diff --git a/js/ui/main.js b/js/ui/main.js
index e0a0953..310a3ed 100644
--- a/js/ui/main.js
+++ b/js/ui/main.js
@@ -218,10 +218,8 @@ function _findModal(actor) {
  * Returns: true iff we successfully acquired a grab or already had one
  */
 function pushModal(actor) {
-    let timestamp = global.screen.get_display().get_current_time();
-
     if (modalCount == 0) {
-        if (!global.begin_modal(timestamp)) {
+        if (!global.begin_modal(currentTime())) {
             log("pushModal: invocation of begin_modal failed");
             return false;
         }
@@ -257,8 +255,6 @@ function pushModal(actor) {
  * previous focus at the time when pushModal() was invoked.
  */
 function popModal(actor) {
-    let timestamp = global.screen.get_display().get_current_time();
-
     modalCount -= 1;
     let focusIndex = _findModal(actor);
     if (focusIndex >= 0) {
@@ -276,7 +272,7 @@ function popModal(actor) {
     if (modalCount > 0)
         return;
 
-    global.end_modal(timestamp);
+    global.end_modal(currentTime());
     global.set_stage_input_mode(Shell.StageInputMode.NORMAL);
 }
 
@@ -296,15 +292,40 @@ function getRunDialog() {
 }
 
 function createAppLaunchContext() {
-    let screen = global.screen;
-    let display = screen.get_display();
-
     let context = new Gdk.AppLaunchContext();
-    context.set_timestamp(display.get_current_time());
+    context.set_timestamp(currentTime());
 
     // Make sure that the app is opened on the current workspace even if
     // the user switches before it starts
-    context.set_desktop(screen.get_active_workspace_index());
+    context.set_desktop(global.screen.get_active_workspace_index());
 
     return context;
 }
+
+/**
+ * currentTime:
+ *
+ * Gets the current X server time from the current Clutter, Gdk, or X
+ * event. If called from outside an event handler, this may return
+ * %Clutter.CURRENT_TIME (aka 0), or it may return a slightly
+ * out-of-date timestamp.
+ */
+function currentTime() {
+    // meta_display_get_current_time() will return the correct time
+    // when handling an X or Gdk event, but will return CurrentTime
+    // from some Clutter event callbacks.
+    //
+    // clutter_get_current_event_time() will return the correct time
+    // from a Clutter event callback, but may return an out-of-date
+    // timestamp if called at other times.
+    //
+    // So we try meta_display_get_current_time() first, since we
+    // can recognize a "wrong" answer from that, and then fall back
+    // to clutter_get_current_event_time().
+
+    let time = global.screen.get_display().get_current_time();
+    if (time != Clutter.CURRENT_TIME)
+        return time;
+
+    return Clutter.get_current_event_time();
+}
diff --git a/js/ui/overview.js b/js/ui/overview.js
index cccf2e4..0600414 100644
--- a/js/ui/overview.js
+++ b/js/ui/overview.js
@@ -442,7 +442,7 @@ Overview.prototype = {
     },
 
     _addNewWorkspace: function() {
-        global.screen.append_new_workspace(false, global.screen.get_display().get_current_time());
+        global.screen.append_new_workspace(false, Main.currentTime());
     },
 
     _acceptNewWorkspaceDrop: function(source, dropActor, x, y, time) {