Merge lp:~robert-ancell/lightdm/unity-vt-fallback into lp:~mir-team/lightdm/unity

[Robert Ancell]

Fall back to VT switching if can't start the system compositor

[Chris Halse Rogers (raof)]

Looks correct to me.

review: Approve

[PS Jenkins bot (ps-jenkins)]

PASSED: Continuous integration, rev:1611
http://jenkins.qa.ubuntu.com/job/mir-team-lightdm-unity-ci/11/
Executed test runs:
    SUCCESS: http://jenkins.qa.ubuntu.com/job/mir-team-lightdm-unity-raring-amd64-ci/11

Click here to trigger a rebuild:
http://s-jenkins:8080/job/mir-team-lightdm-unity-ci/11/rebuild

review: Approve (continuous-integration)

=== modified file 'src/seat-unity.c'
--- src/seat-unity.c	2013-05-20 05:20:45 +0000
+++ src/seat-unity.c	2013-05-31 02:42:33 +0000
@@ -64,8 +64,12 @@
     /* Timeout when waiting for compositor to start */
     guint compositor_timeout;
 
+    /* Next Mir ID to use for a compositor client */
     gint next_id;
 
+    /* TRUE if using VT switching fallback */
+    gboolean use_vt_switching;
+
     /* The currently visible display */
     Display *active_display;
 };
@@ -82,12 +86,25 @@
 static void
 compositor_stopped_cb (Process *process, SeatUnity *seat)
 {
+    if (seat->priv->compositor_timeout != 0)
+        g_source_remove (seat->priv->compositor_timeout);
+    seat->priv->compositor_timeout = 0;
+
     if (seat_get_is_stopping (SEAT (seat)))
     {
         SEAT_CLASS (seat_unity_parent_class)->stop (SEAT (seat));
         return;
     }
 
+    /* If stopped before it was ready, then revert to VT mode */
+    if (!seat->priv->compositor_ready)
+    {
+        g_debug ("Compositor failed to start, switching to VT mode");
+        seat->priv->use_vt_switching = TRUE;
+        SEAT_CLASS (seat_unity_parent_class)->start (SEAT (seat));
+        return;
+    }
+
     g_debug ("Stopping Unity seat, compositor terminated");
 
     if (seat->priv->stopping_plymouth)
@@ -243,8 +260,10 @@
             absolute_command = g_strjoin (" ", absolute_binary, tokens[1], NULL);
         else
             absolute_command = g_strdup (absolute_binary);
+        g_free (absolute_binary);
     }
-    g_free (absolute_binary);
+    else
+        absolute_command = g_strdup (command);
 
     g_strfreev (tokens);
 
@@ -317,11 +336,6 @@
 
     absolute_command = get_absolute_command (command);
     g_free (command);
-    if (!absolute_command)
-    {
-        g_debug ("Can't launch system compositor, not found in path");
-        return FALSE;
-    }
 
     /* Start the compositor */
     process_set_command (SEAT_UNITY (seat)->priv->compositor_process, absolute_command);
@@ -359,11 +373,14 @@
 
     xserver = xserver_local_new ();
 
-    id = g_strdup_printf ("%d", SEAT_UNITY (seat)->priv->next_id);
-    SEAT_UNITY (seat)->priv->next_id++;
-    xserver_local_set_mir_id (xserver, id);
-    xserver_local_set_mir_socket (xserver, SEAT_UNITY (seat)->priv->mir_socket_filename);
-    g_free (id);
+    if (!SEAT_UNITY (seat)->priv->use_vt_switching)
+    {
+        id = g_strdup_printf ("%d", SEAT_UNITY (seat)->priv->next_id);
+        SEAT_UNITY (seat)->priv->next_id++;
+        xserver_local_set_mir_id (xserver, id);
+        xserver_local_set_mir_socket (xserver, SEAT_UNITY (seat)->priv->mir_socket_filename);
+        g_free (id);
+    }
 
     command = seat_get_string_property (seat, "xserver-command");
     if (command)
@@ -437,7 +454,10 @@
     xserver = XSERVER_LOCAL (display_get_display_server (display));
 
     session = xsession_new (XSERVER (xserver));
-    tty = g_strdup_printf ("/dev/tty%d", SEAT_UNITY (seat)->priv->vt);
+    if (SEAT_UNITY (seat)->priv->use_vt_switching)
+        tty = g_strdup_printf ("/dev/tty%d", xserver_local_get_vt (xserver));
+    else
+        tty = g_strdup_printf ("/dev/tty%d", SEAT_UNITY (seat)->priv->vt);
     session_set_tty (SESSION (session), tty);
     g_free (tty);
 
@@ -450,6 +470,17 @@
     XServerLocal *xserver;
     const gchar *id;
 
+    /* If no compositor, have to use VT switching */
+    if (SEAT_UNITY (seat)->priv->use_vt_switching)
+    {
+        gint vt = xserver_local_get_vt (XSERVER_LOCAL (display_get_display_server (display)));
+        if (vt >= 0)
+            vt_set_active (vt);
+
+        SEAT_CLASS (seat_unity_parent_class)->set_active_display (seat, display);
+        return;
+    }
+
     if (display == SEAT_UNITY (seat)->priv->active_display)
         return;
     SEAT_UNITY (seat)->priv->active_display = display;
@@ -466,6 +497,27 @@
 static Display *
 seat_unity_get_active_display (Seat *seat)
 {
+    if (SEAT_UNITY (seat)->priv->use_vt_switching)
+    {
+        gint vt;
+        GList *link;
+        vt = vt_get_active ();
+        if (vt < 0)
+            return NULL;
+
+        for (link = seat_get_displays (seat); link; link = link->next)
+        {
+            Display *display = link->data;
+            XServerLocal *xserver;
+
+            xserver = XSERVER_LOCAL (display_get_display_server (display));
+            if (xserver_local_get_vt (xserver) == vt)
+                return display;
+        }
+
+        return NULL;
+    }
+
     return SEAT_UNITY (seat)->priv->active_display;
 }
 

=== modified file 'tests/scripts/unity-compositor-fail-start.conf'
--- tests/scripts/unity-compositor-fail-start.conf	2013-05-20 05:20:45 +0000
+++ tests/scripts/unity-compositor-fail-start.conf	2013-05-31 02:42:33 +0000
@@ -1,5 +1,5 @@
 #
-# Check quits when the compositor fails to start
+# Check falls back to VT swithcing when the compositor fails to start
 #
 
 [unity-system-compositor-config]
@@ -14,5 +14,22 @@
 #?UNITY-SYSTEM-COMPOSITOR START
 #?UNITY-SYSTEM-COMPOSITOR EXIT CODE=1
 
-# Daemon stops with error
-#?RUNNER DAEMON-EXIT STATUS=1
+# X server starts in VT mode
+#?XSERVER-0 START
+#?XSERVER-0 INDICATE-READY
+
+# LightDM connects to X server
+#?XSERVER-0 ACCEPT-CONNECT
+
+# Greeter starts
+#?GREETER-X-0 START
+#?XSERVER-0 ACCEPT-CONNECT
+#?GREETER-X-0 CONNECT-XSERVER
+#?GREETER-X-0 CONNECT-TO-DAEMON
+#?GREETER-X-0 CONNECTED-TO-DAEMON
+
+# Cleanup
+#?*STOP-DAEMON
+#?GREETER-X-0 TERMINATE SIGNAL=15
+#?XSERVER-0 TERMINATE SIGNAL=15
+#?RUNNER DAEMON-EXIT STATUS=0