[gdm/plymouth-integration: 2/2] Enable smooth transition between plymouth and X

[Ray Strode <halfline src gnome org>]

commit 2343620d464b93cfa46abddf8af14c7268f17df2
Author: Ray Strode <rstrode redhat com>
Date:   Fri Nov 27 18:52:54 2009 -0500

    Enable smooth transition between plymouth and X
    
    This commit checks if plymouth is running, and if so,
    turns on the smooth transition between plymouth and X.

 daemon/gdm-server.c       |   56 +++++++++++++++++++++++++++
 daemon/gdm-server.h       |    1 +
 daemon/gdm-simple-slave.c |   91 ++++++++++++++++++++++++++++++++++++++++++++-
 3 files changed, 147 insertions(+), 1 deletions(-)
---
diff --git a/daemon/gdm-server.c b/daemon/gdm-server.c
index ba10386..3ec21e9 100644
--- a/daemon/gdm-server.c
+++ b/daemon/gdm-server.c
@@ -32,8 +32,11 @@
 #include <pwd.h>
 #include <grp.h>
 #include <signal.h>
+#include <sys/ioctl.h>
 #include <sys/resource.h>
 
+#include <linux/vt.h>
+
 #include <glib.h>
 #include <glib/gi18n.h>
 #include <glib/gstdio.h>
@@ -663,6 +666,44 @@ gdm_server_spawn (GdmServer  *server,
         return ret;
 }
 
+static int
+get_active_vt (void)
+{
+        int console_fd;
+        struct vt_stat console_state = { 0 };
+
+        console_fd = open ("/dev/tty0", O_RDONLY | O_NOCTTY);
+
+        if (console_fd < 0) {
+                goto out;
+        }
+
+        if (ioctl (console_fd, VT_GETSTATE, &console_state) < 0) {
+                goto out;
+        }
+
+out:
+        if (console_fd >= 0) {
+                close (console_fd);
+        }
+
+        return console_state.v_active;
+}
+
+static char *
+get_active_vt_as_string (void)
+{
+        int vt;
+
+        vt = get_active_vt ();
+
+        if (vt <= 0) {
+                return NULL;
+        }
+
+        return g_strdup_printf ("vt%d", vt);
+}
+
 /**
  * gdm_server_start:
  * @disp: Pointer to a GdmDisplay structure
@@ -681,6 +722,21 @@ gdm_server_start (GdmServer *server)
         return res;
 }
 
+gboolean
+gdm_server_start_on_active_vt (GdmServer *server)
+{
+        gboolean res;
+        char *vt;
+
+        g_free (server->priv->command);
+        server->priv->command = g_strdup (X_SERVER " -nr -verbose");
+        vt = get_active_vt_as_string ();
+        res = gdm_server_spawn (server, vt);
+        g_free (vt);
+
+        return res;
+}
+
 static void
 server_died (GdmServer *server)
 {
diff --git a/daemon/gdm-server.h b/daemon/gdm-server.h
index 535a69a..bd6c60a 100644
--- a/daemon/gdm-server.h
+++ b/daemon/gdm-server.h
@@ -56,6 +56,7 @@ GType               gdm_server_get_type  (void);
 GdmServer *         gdm_server_new       (const char *display_id,
                                           const char *auth_file);
 gboolean            gdm_server_start     (GdmServer   *server);
+gboolean            gdm_server_start_on_active_vt (GdmServer   *server);
 gboolean            gdm_server_stop      (GdmServer   *server);
 char *              gdm_server_get_display_device (GdmServer *server);
 
diff --git a/daemon/gdm-simple-slave.c b/daemon/gdm-simple-slave.c
index 66d1c77..4703537 100644
--- a/daemon/gdm-simple-slave.c
+++ b/daemon/gdm-simple-slave.c
@@ -84,6 +84,7 @@ struct GdmSimpleSlavePrivate
 
         guint              start_session_when_ready : 1;
         guint              waiting_to_start_session : 1;
+        guint              plymouth_is_running : 1;
 };
 
 enum {
@@ -858,6 +859,72 @@ on_start_session_later (GdmGreeterServer *session,
         slave->priv->start_session_when_ready = FALSE;
 }
 
+static gboolean
+plymouth_is_running (void)
+{
+        int      status;
+        gboolean res;
+        GError  *error;
+
+        error = NULL;
+        res = g_spawn_command_line_sync ("/bin/plymouth --ping",
+                                         NULL, NULL, &status, &error);
+        if (! res) {
+                g_debug ("Could not ping plymouth: %s", error->message);
+                g_error_free (error);
+                return FALSE;
+        }
+
+        return WIFEXITED (status) && WEXITSTATUS (status) == 0;
+}
+
+static void
+plymouth_prepare_for_transition (GdmSimpleSlave *slave)
+{
+        gboolean res;
+        GError  *error;
+
+        error = NULL;
+        res = g_spawn_command_line_sync ("/bin/plymouth deactivate",
+                                         NULL, NULL, NULL, &error);
+        if (! res) {
+                g_warning ("Could not deactivate plymouth: %s", error->message);
+                g_error_free (error);
+        }
+}
+
+static void
+plymouth_quit_with_transition (GdmSimpleSlave *slave)
+{
+        gboolean res;
+        GError  *error;
+
+        error = NULL;
+        res = g_spawn_command_line_sync ("/bin/plymouth quit --retain-splash",
+                                         NULL, NULL, NULL, &error);
+        if (! res) {
+                g_warning ("Could not quit plymouth: %s", error->message);
+                g_error_free (error);
+        }
+        slave->priv->plymouth_is_running = FALSE;
+}
+
+static void
+plymouth_quit_without_transition (GdmSimpleSlave *slave)
+{
+        gboolean res;
+        GError  *error;
+
+        error = NULL;
+        res = g_spawn_command_line_sync ("/bin/plymouth quit",
+                                         NULL, NULL, NULL, &error);
+        if (! res) {
+                g_warning ("Could not quit plymouth: %s", error->message);
+                g_error_free (error);
+        }
+        slave->priv->plymouth_is_running = FALSE;
+}
+
 static void
 setup_server (GdmSimpleSlave *slave)
 {
@@ -872,6 +939,10 @@ setup_server (GdmSimpleSlave *slave)
          */
         gdm_slave_save_root_windows (GDM_SLAVE (slave));
 
+        /* Plymouth is waiting for the go-ahead to exit */
+        if (slave->priv->plymouth_is_running) {
+                plymouth_quit_with_transition (slave);
+        }
 }
 
 static void
@@ -1063,6 +1134,10 @@ on_server_exited (GdmServer      *server,
         g_debug ("GdmSimpleSlave: server exited with code %d\n", exit_code);
 
         gdm_slave_stopped (GDM_SLAVE (slave));
+
+        if (slave->priv->plymouth_is_running) {
+                plymouth_quit_without_transition (slave);
+        }
 }
 
 static void
@@ -1075,6 +1150,10 @@ on_server_died (GdmServer      *server,
                  g_strsignal (signal_number));
 
         gdm_slave_stopped (GDM_SLAVE (slave));
+
+        if (slave->priv->plymouth_is_running) {
+                plymouth_quit_without_transition (slave);
+        }
 }
 
 static gboolean
@@ -1119,7 +1198,14 @@ gdm_simple_slave_run (GdmSimpleSlave *slave)
                                   G_CALLBACK (on_server_ready),
                                   slave);
 
-                res = gdm_server_start (slave->priv->server);
+                slave->priv->plymouth_is_running = plymouth_is_running ();
+
+                if (slave->priv->plymouth_is_running) {
+                        plymouth_prepare_for_transition (slave);
+                        res = gdm_server_start_on_active_vt (slave->priv->server);
+                } else {
+                        res = gdm_server_start (slave->priv->server);
+                }
                 if (! res) {
                         g_warning (_("Could not start the X "
                                      "server (your graphical environment) "
@@ -1129,6 +1215,9 @@ gdm_simple_slave_run (GdmSimpleSlave *slave)
                                      "In the meantime this display will be "
                                      "disabled.  Please restart GDM when "
                                      "the problem is corrected."));
+                        if (slave->priv->plymouth_is_running) {
+                                plymouth_quit_without_transition (slave);
+                        }
                         exit (1);
                 }