daemon: run PostSession script from mnager not worker

After a user logs out, the session worker baby sitting
the session, may optionally run admin provided PostSession
scripts.

Those scripts aren't getting reliably run on reboots, because
systemd kills the worker prematurely.

There's no easy way to prevent this... the worker is part of
the user session and user sessions are terminated immediately
at shutdown time.

This commit moves PostSession handling to the daemon process,
where it can happen unimpeded by session bring down.

This also makes the scripts more reliable in other potential
cases where the worker is killed explicitly.

2 files changed, 40 insertions, 3 deletions

diff --git a/daemon/gdm-manager.c b/daemon/gdm-manager.c
index 779b716b..d31c9d71 100644
--- a/daemon/gdm-manager.c
+++ b/daemon/gdm-manager.c
@@ -1961,6 +1961,41 @@ on_user_session_started (GdmSession      *session,
 }
 
 static void
+run_post_session_script (GdmSession *session)
+{
+        GPid pid;
+        GdmDisplay *display;
+        gboolean display_is_local = FALSE;
+        const char *username;
+        g_autofree char *display_name = NULL, *remote_hostname = NULL, *display_auth_file = NULL;
+
+        display = get_display_for_user_session (session);
+
+        if (display == NULL)
+                return;
+
+        pid = gdm_session_get_pid (session);
+
+        if (pid <= 0)
+                return;
+
+        username = gdm_session_get_username (session);
+
+        g_object_get (G_OBJECT (display),
+                      "x11-display-name", &display_name,
+                      "is-local", &display_is_local,
+                      "remote-hostname", &remote_hostname,
+                      "x11-authority-file", &display_auth_file,
+                      NULL);
+
+        gdm_run_script (GDMCONFDIR "/PostSession",
+                        username,
+                        display_name,
+                        display_is_local? NULL : remote_hostname,
+                        display_auth_file);
+}
+
+static void
 remove_user_session (GdmManager *manager,
                      GdmSession *session)
 {
@@ -1970,6 +2005,8 @@ remove_user_session (GdmManager *manager,
         display = get_display_for_user_session (session);
 
         if (display != NULL) {
+                run_post_session_script (session);
+
                 gdm_display_unmanage (display);
                 gdm_display_finish (display);
         }
@@ -2781,6 +2818,9 @@ gdm_manager_dispose (GObject *object)
                          g_hash_table_unref);
 
         g_list_foreach (manager->priv->user_sessions,
+                        (GFunc) run_post_session_script,
+                        NULL);
+        g_list_foreach (manager->priv->user_sessions,
                         (GFunc) gdm_session_close,
                         NULL);
         g_list_free_full (manager->priv->user_sessions, (GDestroyNotify) g_object_unref);
diff --git a/daemon/gdm-session-worker.c b/daemon/gdm-session-worker.c
index 07117d85..b0861b97 100644
--- a/daemon/gdm-session-worker.c
+++ b/daemon/gdm-session-worker.c
@@ -1770,18 +1770,15 @@ session_worker_child_watch (GPid              pid,
                  : WIFSIGNALED (status) ? WTERMSIG (status)
                  : -1);
 
-
         gdm_session_worker_uninitialize_pam (worker, PAM_SUCCESS);
 
         gdm_dbus_worker_emit_session_exited (GDM_DBUS_WORKER (worker),
                                              worker->priv->service,
                                              status);
-
         killpg (pid, SIGHUP);
 
         worker->priv->child_pid = -1;
         worker->priv->child_watch_id = 0;
-        run_script (worker, GDMCONFDIR "/PostSession");
 }
 
 static void