mutter/src/core/restart.c
Jonas Ådahl 2f4a68c8c3 Clean up include macros mess
The order and way include macros were structured was chaotic, with no
real common thread between files. Try to tidy up the mess with some
common scheme, to make things look less messy.
2018-11-06 17:17:36 +01:00

197 lines
6.0 KiB
C

/* -*- mode: C; c-file-style: "gnu"; indent-tabs-mode: nil; -*- */
/*
* Copyright (C) 2014 Red Hat, Inc.
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License as
* published by the Free Software Foundation; either version 2 of the
* License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, see <http://www.gnu.org/licenses/>.
*/
/*
* SECTION:restart
* @short_description: Smoothly restart the compositor
*
* There are some cases where we need to restart Mutter in order
* to deal with changes in state - the particular case inspiring
* this is enabling or disabling stereo output. To make this
* fairly smooth for the user, we need to do two things:
*
* - Display a message to the user and make sure that it is
* actually painted before we exit.
* - Use a helper program so that the Composite Overlay Window
* isn't unmapped and mapped.
*
* This handles both of these.
*/
#include "config.h"
#include <gio/gunixinputstream.h>
#include "clutter/clutter.h"
#include "core/display-private.h"
#include "core/util-private.h"
#include "meta/main.h"
#include "ui/ui.h"
#include "x11/meta-x11-display-private.h"
static gboolean restart_helper_started = FALSE;
static gboolean restart_message_shown = FALSE;
static gboolean is_restart = FALSE;
void
meta_set_is_restart (gboolean whether)
{
is_restart = whether;
}
static void
restart_check_ready (void)
{
if (restart_helper_started && restart_message_shown)
meta_display_request_restart (meta_get_display ());
}
static void
restart_helper_read_line_callback (GObject *source_object,
GAsyncResult *res,
gpointer user_data)
{
GError *error = NULL;
gsize length;
char *line = g_data_input_stream_read_line_finish_utf8 (G_DATA_INPUT_STREAM (source_object),
res,
&length, &error);
if (line == NULL)
{
meta_warning ("Failed to read output from restart helper%s%s\n",
error ? ": " : NULL,
error ? error->message : NULL);
}
else
g_free (line); /* We don't actually care what the restart helper outputs */
g_object_unref (source_object);
restart_helper_started = TRUE;
restart_check_ready ();
}
static gboolean
restart_message_painted (gpointer data)
{
restart_message_shown = TRUE;
restart_check_ready ();
return FALSE;
}
/**
* meta_restart:
* @message: (allow-none): message to display to the user, or %NULL
*
* Starts the process of restarting the compositor. Note that Mutter's
* involvement here is to make the restart visually smooth for the
* user - it cannot itself safely reexec a program that embeds libmuttter.
* So in order for this to work, the compositor must handle two
* signals - MetaDisplay::show-restart-message, to display the
* message passed here on the Clutter stage, and ::restart to actually
* reexec the compositor.
*/
void
meta_restart (const char *message)
{
MetaDisplay *display = meta_get_display();
GInputStream *unix_stream;
GDataInputStream *data_stream;
GError *error = NULL;
int helper_out_fd;
static const char * const helper_argv[] = {
MUTTER_LIBEXECDIR "/mutter-restart-helper", NULL
};
if (message && meta_display_show_restart_message (display, message))
{
/* Wait until the stage was painted */
clutter_threads_add_repaint_func_full (CLUTTER_REPAINT_FLAGS_POST_PAINT,
restart_message_painted,
NULL, NULL);
}
else
{
/* Can't show the message, show the message as soon as the
* restart helper starts
*/
restart_message_painted (NULL);
}
/* We also need to wait for the restart helper to get its
* reference to the Composite Overlay Window.
*/
if (!g_spawn_async_with_pipes (NULL, /* working directory */
(char **)helper_argv,
NULL, /* envp */
G_SPAWN_DEFAULT,
NULL, NULL, /* child_setup */
NULL, /* child_pid */
NULL, /* standard_input */
&helper_out_fd,
NULL, /* standard_error */
&error))
{
meta_warning ("Failed to start restart helper: %s\n", error->message);
goto error;
}
unix_stream = g_unix_input_stream_new (helper_out_fd, TRUE);
data_stream = g_data_input_stream_new (unix_stream);
g_object_unref (unix_stream);
g_data_input_stream_read_line_async (data_stream, G_PRIORITY_DEFAULT,
NULL, restart_helper_read_line_callback,
&error);
if (error != NULL)
{
meta_warning ("Failed to read from restart helper: %s\n", error->message);
g_object_unref (data_stream);
goto error;
}
return;
error:
/* If starting the restart helper fails, then we just go ahead and restart
* immediately. We won't get a smooth transition, since the overlay window
* will be destroyed and recreated, but otherwise it will work fine.
*/
restart_helper_started = TRUE;
restart_check_ready ();
return;
}
/**
* meta_is_restart:
*
* Returns %TRUE if this instance of Mutter comes from Mutter
* restarting itself (for example to enable/disable stereo.)
* See meta_restart(). If this is the case, any startup visuals
* or animations should be suppressed.
*/
gboolean
meta_is_restart (void)
{
return is_restart;
}