Add graphical session support

cinnamon-session/csm-manager.c

@@ -67,7 +67,7 @@
  * want to wait, at least for something happening more than once.
  * We can get deployed on very slow media though like CDROM devices,
  * often with complex stacking/compressing filesystems on top, which
  * is not a recipie for speed.   Particularly now that we throw up
  * a fail whale if required components don't show up quickly enough,
  * let's make this fairly long.
  */
@@ -953,6 +953,8 @@
 static void
 do_phase_exit (CsmManager *manager)
 {
+        csm_util_stop_systemd_unit ("cinnamon-session.target", NULL);
+
         if (csm_store_size (manager->priv->clients) > 0) {
                 csm_store_foreach (manager->priv->clients,
                                    (CsmStoreFunc)_client_stop,
@@ -1523,6 +1525,7 @@
                 csm_xsmp_server_start_accepting_new_clients (manager->priv->xsmp_server);
                 csm_exported_manager_emit_session_running (manager->priv->skeleton);
                 update_idle (manager);
+                csm_util_start_systemd_unit ("cinnamon-session.target", NULL);
                 break;
         case CSM_MANAGER_PHASE_QUERY_END_SESSION:
                 csm_xsmp_server_stop_accepting_new_clients (manager->priv->xsmp_server);

cinnamon-session/csm-util.c

@@ -763,6 +763,201 @@ csm_util_update_user_environment (const char  *variable,
         return environment_updated;
 }
 
+static const char * const csm_systemd_env_denylist[] = {
+        "XDG_SESSION_ID",
+        "XDG_SESSION_TYPE",
+        "XDG_SESSION_CLASS",
+        "XDG_SESSION_DESKTOP",
+        "XDG_SEAT",
+        "XDG_VTNR",
+        "NOTIFY_SOCKET",
+        NULL
+};
+
+gboolean
+csm_util_export_systemd_activation_environment (GError **error)
+{
+        GDBusConnection *connection;
+        GVariantBuilder  builder;
+        GVariant        *reply;
+        GError          *bus_error = NULL;
+        GRegex          *name_regex, *value_regex;
+        char           **entry_names;
+        int              i = 0;
+        gboolean         environment_updated = FALSE;
+
+        if (access ("/run/systemd/private", F_OK) != 0)
+                return TRUE;
+
+        connection = g_bus_get_sync (G_BUS_TYPE_SESSION, NULL, error);
+        if (connection == NULL)
+                return FALSE;
+
+        name_regex = g_regex_new ("^[a-zA-Z_][a-zA-Z0-9_]*$",
+                                  G_REGEX_OPTIMIZE, 0, error);
+        if (name_regex == NULL) {
+                g_object_unref (connection);
+                return FALSE;
+        }
+
+        value_regex = g_regex_new ("^([[:blank:]]|[^[:cntrl:]])*$",
+                                   G_REGEX_OPTIMIZE, 0, error);
+        if (value_regex == NULL) {
+                g_regex_unref (name_regex);
+                g_object_unref (connection);
+                return FALSE;
+        }
+
+        g_variant_builder_init (&builder, G_VARIANT_TYPE ("as"));
+
+        entry_names = g_listenv ();
+        for (i = 0; entry_names[i] != NULL; i++) {
+                const char *entry_name  = entry_names[i];
+                const char *entry_value = g_getenv (entry_name);
+
+                if (g_strv_contains (csm_systemd_env_denylist, entry_name))
+                        continue;
+
+                if (!g_utf8_validate (entry_name, -1, NULL))
+                        continue;
+
+                if (!g_regex_match (name_regex, entry_name, 0, NULL))
+                        continue;
+
+                if (entry_value == NULL)
+                        continue;
+
+                if (!g_utf8_validate (entry_value, -1, NULL))
+                        continue;
+
+                if (!g_regex_match (value_regex, entry_value, 0, NULL))
+                        continue;
+
+                g_variant_builder_add (&builder, "s",
+                                       g_strdup_printf ("%s=%s",
+                                                        entry_name,
+                                                        entry_value));
+        }
+        g_regex_unref (name_regex);
+        g_regex_unref (value_regex);
+        g_strfreev (entry_names);
+
+        reply = g_dbus_connection_call_sync (connection,
+                                             "org.freedesktop.systemd1",
+                                             "/org/freedesktop/systemd1",
+                                             "org.freedesktop.systemd1.Manager",
+                                             "SetEnvironment",
+                                             g_variant_new ("(@as)",
+                                                            g_variant_builder_end (&builder)),
+                                             NULL,
+                                             G_DBUS_CALL_FLAGS_NONE,
+                                             -1, NULL, &bus_error);
+
+        if (bus_error != NULL) {
+                g_warning ("csm_util_export_systemd_activation_environment: "
+                           "failed to export to systemd: %s",
+                           bus_error->message);
+                if (error != NULL)
+                        g_propagate_error (error, bus_error);
+                else
+                        g_error_free (bus_error);
+        } else {
+                environment_updated = TRUE;
+                g_variant_unref (reply);
+        }
+
+        g_object_unref (connection);
+        return environment_updated;
+}
+
+gboolean
+csm_util_start_systemd_unit (const char *unit,
+                              GError    **error)
+{
+        GDBusConnection *connection;
+        GVariant        *reply;
+        GError          *bus_error = NULL;
+        gboolean         ret = FALSE;
+
+        if (access ("/run/systemd/private", F_OK) != 0)
+                return TRUE;
+
+        connection = g_bus_get_sync (G_BUS_TYPE_SESSION, NULL, error);
+        if (connection == NULL)
+                return FALSE;
+
+        g_debug ("csm_util_start_systemd_unit: starting %s", unit);
+
+        reply = g_dbus_connection_call_sync (connection,
+                                             "org.freedesktop.systemd1",
+                                             "/org/freedesktop/systemd1",
+                                             "org.freedesktop.systemd1.Manager",
+                                             "StartUnit",
+                                             g_variant_new ("(ss)", unit, "replace"),
+                                             G_VARIANT_TYPE ("(o)"),
+                                             G_DBUS_CALL_FLAGS_NONE,
+                                             -1, NULL, &bus_error);
+
+        if (bus_error != NULL) {
+                g_warning ("csm_util_start_systemd_unit: failed to start %s: %s",
+                           unit, bus_error->message);
+                if (error != NULL)
+                        g_propagate_error (error, bus_error);
+                else
+                        g_error_free (bus_error);
+        } else {
+                ret = TRUE;
+                g_variant_unref (reply);
+        }
+
+        g_object_unref (connection);
+        return ret;
+}
+
+gboolean
+csm_util_stop_systemd_unit (const char *unit,
+                             GError    **error)
+{
+        GDBusConnection *connection;
+        GVariant        *reply;
+        GError          *bus_error = NULL;
+        gboolean         ret = FALSE;
+
+        if (access ("/run/systemd/private", F_OK) != 0)
+                return TRUE;
+
+        connection = g_bus_get_sync (G_BUS_TYPE_SESSION, NULL, error);
+        if (connection == NULL)
+                return FALSE;
+
+        g_debug ("csm_util_stop_systemd_unit: stopping %s", unit);
+
+        reply = g_dbus_connection_call_sync (connection,
+                                             "org.freedesktop.systemd1",
+                                             "/org/freedesktop/systemd1",
+                                             "org.freedesktop.systemd1.Manager",
+                                             "StopUnit",
+                                             g_variant_new ("(ss)", unit, "replace"),
+                                             G_VARIANT_TYPE ("(o)"),
+                                             G_DBUS_CALL_FLAGS_NONE,
+                                             -1, NULL, &bus_error);
+
+        if (bus_error != NULL) {
+                g_debug ("csm_util_stop_systemd_unit: failed to stop %s: %s",
+                         unit, bus_error->message);
+                if (error != NULL)
+                        g_propagate_error (error, bus_error);
+                else
+                        g_error_free (bus_error);
+        } else {
+                ret = TRUE;
+                g_variant_unref (reply);
+        }
+
+        g_object_unref (connection);
+        return ret;
+}
+
 void
 csm_util_setenv (const char *variable,
                  const char *value)

cinnamon-session/csm-util.h

@@ -58,6 +58,13 @@ gboolean    csm_util_export_user_environment        (GError     **error);
 void        csm_util_setenv                         (const char *variable,
                                                      const char *value);
 
+gboolean    csm_util_export_systemd_activation_environment (GError     **error);
+
+gboolean    csm_util_start_systemd_unit                  (const char  *unit,
+                                                          GError     **error);
+gboolean    csm_util_stop_systemd_unit                   (const char  *unit,
+                                                          GError     **error);
+
 // main.c, exit mainloop
 void        csm_quit                                (void);
 

cinnamon-session/main.c

@@ -265,6 +265,13 @@ main (int argc, char **argv)
         csm_util_export_activation_environment (NULL);
         csm_util_export_user_environment (NULL);
 
+        if (!csm_util_export_systemd_activation_environment (NULL)) {
+                g_warning ("main: failed to export environment to systemd --user; "
+                           "some systemd-managed services may not start correctly");
+        }
+
+        csm_util_start_systemd_unit ("cinnamon-session.target", NULL);
+
         {
                 gchar *ibus_path;
 

data/meson.build

@@ -20,3 +20,6 @@ install_data(
 
 # Re-compile gsettings
 meson.add_install_script('meson_install_schemas.py')
+
+subdir('systemd/user')
+

data/systemd/user/cinnamon-session.target

@@ -0,0 +1,10 @@
+[Unit]
+Description=Cinnamon graphical session
+Documentation=man:systemd.special(7)
+Wants=graphical-session.target
+Wants=graphical-session-pre.target
+After=graphical-session-pre.target
+After=graphical-session.target
+PropagatesStopTo=graphical-session.target
+PropagatesStopTo=graphical-session-pre.target
+CollectMode=inactive-or-failed

data/systemd/user/meson.build

@@ -0,0 +1,6 @@
+install_data(
+  [
+    'cinnamon-session.target',
+  ],
+  install_dir: systemduserunitdir,
+)

meson.build

@@ -58,6 +58,15 @@
 endif
 conf.set('HAVE_LOGIND', logind.found())
 
+if libsystemdl.found()
+  systemduserunitdir = libsystemdl.get_variable(
+    pkgconfig: 'systemduserunitdir',
+    default_value: join_paths(get_option('prefix'), 'lib', 'systemd', 'user'),
+  )
+else
+  systemduserunitdir = join_paths(get_option('prefix'), 'lib', 'systemd', 'user')
+endif
+
 if gio_unix.found() and libelogind.found()
   elogind = declare_dependency(dependencies: [ gio_unix, libelogind ])
 else
@@ -119,7 +128,7 @@
 conf.set('ENABLE_IPV6', have_ipv6)
 
 ################################################################################
 # Additionnal flags
 
 rootInclude = include_directories('.')