]> rtime.felk.cvut.cz Git - sojka/lightdm.git/blob - src/seat.c
Fix invalid unref when fail to start seat. Add regression test for this case
[sojka/lightdm.git] / src / seat.c
1 /*
2  * Copyright (C) 2010-2011 Robert Ancell.
3  * Author: Robert Ancell <robert.ancell@canonical.com>
4  *
5  * This program is free software: you can redistribute it and/or modify it under
6  * the terms of the GNU General Public License as published by the Free Software
7  * Foundation, either version 3 of the License, or (at your option) any later
8  * version. See http://www.gnu.org/copyleft/gpl.html the full text of the
9  * license.
10  */
11
12 #include <stdlib.h>
13 #include <string.h>
14 #include <sys/wait.h>
15
16 #include "seat.h"
17 #include "configuration.h"
18 #include "guest-account.h"
19 #include "greeter-session.h"
20 #include "session-config.h"
21
22 enum {
23     SESSION_ADDED,
24     RUNNING_USER_SESSION,
25     SESSION_REMOVED,
26     STOPPED,
27     LAST_SIGNAL
28 };
29 static guint signals[LAST_SIGNAL] = { 0 };
30
31 struct SeatPrivate
32 {
33     /* XDG name for this seat */
34     gchar *name;
35
36     /* Configuration for this seat */
37     GHashTable *properties;
38
39     /* TRUE if this seat can run multiple sessions at once */
40     gboolean supports_multi_session;
41
42     /* TRUE if display server can be shared for sessions */
43     gboolean share_display_server;
44
45     /* The display servers on this seat */
46     GList *display_servers;
47
48     /* The sessions on this seat */
49     GList *sessions;
50
51     /* The last session set to active */
52     Session *active_session;
53
54     /* The session belonging to the active greeter user */
55     Session *next_session;
56
57     /* The session to set active when it starts */
58     Session *session_to_activate;
59
60     /* TRUE once we have started */
61     gboolean started;
62
63     /* TRUE if stopping this seat (waiting for displays to stop) */
64     gboolean stopping;
65
66     /* TRUE if stopped */
67     gboolean stopped;
68     
69     /* The greeter to be started to replace the current one */
70     GreeterSession *replacement_greeter;
71 };
72
73 static void seat_logger_iface_init (LoggerInterface *iface);
74
75 G_DEFINE_TYPE_WITH_CODE (Seat, seat, G_TYPE_OBJECT,
76                          G_IMPLEMENT_INTERFACE (
77                              LOGGER_TYPE, seat_logger_iface_init));
78
79 typedef struct
80 {
81     const gchar *name;
82     GType type;
83 } SeatModule;
84 static GHashTable *seat_modules = NULL;
85
86 // FIXME: Make a get_display_server() that re-uses display servers if supported
87 static DisplayServer *create_display_server (Seat *seat, Session *session);
88 static GreeterSession *create_greeter_session (Seat *seat);
89 static void start_session (Seat *seat, Session *session);
90
91 void
92 seat_register_module (const gchar *name, GType type)
93 {
94     SeatModule *module;
95
96     if (!seat_modules)
97         seat_modules = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, NULL);
98
99     g_debug ("Registered seat module %s", name);
100
101     module = g_malloc0 (sizeof (SeatModule));
102     module->name = g_strdup (name);
103     module->type = type;
104     g_hash_table_insert (seat_modules, g_strdup (name), module);
105 }
106
107 Seat *
108 seat_new (const gchar *module_name, const gchar *name)
109 {
110     Seat *seat;
111     SeatModule *m = NULL;
112
113     g_return_val_if_fail (module_name != NULL, NULL);
114
115     if (seat_modules)
116         m = g_hash_table_lookup (seat_modules, module_name);
117     if (!m)
118         return NULL;
119
120     seat = g_object_new (m->type, NULL);
121     seat->priv->name = g_strdup (name);
122
123     return seat;
124 }
125
126 void
127 seat_set_property (Seat *seat, const gchar *name, const gchar *value)
128 {
129     g_return_if_fail (seat != NULL);
130     g_hash_table_insert (seat->priv->properties, g_strdup (name), g_strdup (value));
131 }
132
133 const gchar *
134 seat_get_string_property (Seat *seat, const gchar *name)
135 {
136     g_return_val_if_fail (seat != NULL, NULL);
137     return g_hash_table_lookup (seat->priv->properties, name);
138 }
139
140 gchar **
141 seat_get_string_list_property (Seat *seat, const gchar *name)
142 {
143     g_return_val_if_fail (seat != NULL, NULL);
144     return g_strsplit (g_hash_table_lookup (seat->priv->properties, name), ";", 0);
145 }
146
147 gboolean
148 seat_get_boolean_property (Seat *seat, const gchar *name)
149 {
150     const gchar *value;
151     gint i, length = 0;
152
153     value = seat_get_string_property (seat, name);
154     if (!value)
155         return FALSE;
156
157     /* Count the number of non-whitespace characters */
158     for (i = 0; value[i]; i++)
159         if (!g_ascii_isspace (value[i]))
160             length = i + 1;
161
162     return strncmp (value, "true", MAX (length, 4)) == 0;
163 }
164
165 gint
166 seat_get_integer_property (Seat *seat, const gchar *name)
167 {
168     const gchar *value;
169
170     value = seat_get_string_property (seat, name);
171     return value ? atoi (value) : 0;
172 }
173
174 const gchar *
175 seat_get_name (Seat *seat)
176 {
177     return seat->priv->name;
178 }
179
180 void
181 seat_set_supports_multi_session (Seat *seat, gboolean supports_multi_session)
182 {
183     g_return_if_fail (seat != NULL);
184     seat->priv->supports_multi_session = supports_multi_session;
185 }
186
187 void
188 seat_set_share_display_server (Seat *seat, gboolean share_display_server)
189 {
190     g_return_if_fail (seat != NULL);
191     seat->priv->share_display_server = share_display_server;
192 }
193
194 gboolean
195 seat_start (Seat *seat)
196 {
197     g_return_val_if_fail (seat != NULL, FALSE);
198
199     l_debug (seat, "Starting");
200
201     SEAT_GET_CLASS (seat)->setup (seat);
202     seat->priv->started = SEAT_GET_CLASS (seat)->start (seat);
203
204     return seat->priv->started;
205 }
206
207 GList *
208 seat_get_sessions (Seat *seat)
209 {
210     g_return_val_if_fail (seat != NULL, NULL);
211     return seat->priv->sessions;
212 }
213
214 static gboolean
215 set_greeter_idle (gpointer greeter)
216 {
217     greeter_idle (GREETER (greeter));
218     return FALSE;
219 }
220
221 void
222 seat_set_active_session (Seat *seat, Session *session)
223 {
224     GList *link;
225
226     g_return_if_fail (seat != NULL);
227
228     SEAT_GET_CLASS (seat)->set_active_session (seat, session);
229
230     /* Stop any greeters */
231     for (link = seat->priv->sessions; link; link = link->next)
232     {
233         Session *s = link->data;
234
235         if (s == session || session_get_is_stopping (s))
236             continue;
237
238         if (IS_GREETER_SESSION (s))
239         {
240             Greeter *greeter = greeter_session_get_greeter (GREETER_SESSION (s));
241             if (greeter_get_resettable (greeter))
242             {
243                 if (seat->priv->active_session == s)
244                 {
245                     l_debug (seat, "Idling greeter");
246                     /* Do this in an idle callback, because we might very well
247                        be in the middle of responding to a START_SESSION
248                        request by a greeter.  So they won't expect an IDLE
249                        call during that.  Plus, this isn't time-sensitive. */
250                     g_idle_add (set_greeter_idle, greeter);
251                 }
252             }
253             else
254             {
255                 l_debug (seat, "Stopping greeter");
256                 session_stop (s);
257             }
258         }
259     }
260
261     /* Lock previous sessions */
262     if (seat->priv->active_session && session != seat->priv->active_session && !IS_GREETER_SESSION (seat->priv->active_session))
263         session_lock (seat->priv->active_session);
264
265     session_activate (session);
266     g_clear_object (&seat->priv->active_session);
267     seat->priv->active_session = g_object_ref (session);
268 }
269
270 Session *
271 seat_get_active_session (Seat *seat)
272 {
273     g_return_val_if_fail (seat != NULL, NULL);
274     return SEAT_GET_CLASS (seat)->get_active_session (seat);
275 }
276
277 Session *
278 seat_get_next_session (Seat *seat)
279 {
280     g_return_val_if_fail (seat != NULL, NULL);
281     return seat->priv->next_session;
282 }
283
284 /**
285  * Obtains the active session which lightdm expects to be active.
286  *
287  * This function is different from seat_get_active_session() in that the
288  * later (in the case of xlocal seats) dynamically finds the session that is
289  * really active (based on the active VT), whereas this function returns the
290  * session that lightdm activated last by itself, which may not be the actual
291  * active session (i.e. VT changes).
292  */
293 Session *
294 seat_get_expected_active_session (Seat *seat)
295 {
296     g_return_val_if_fail (seat != NULL, NULL);
297     return seat->priv->active_session;
298 }
299
300 /**
301  * Sets the active session which lightdm expects to be active.
302  *
303  * This function is different from seat_set_active_session() in that the
304  * later performs an actual session activation, whereas this function just
305  * updates the active session after the session has been activated by some
306  * means external to lightdm (i.e. VT changes).
307  */
308 void
309 seat_set_externally_activated_session (Seat *seat, Session *session)
310 {
311     g_return_if_fail (seat != NULL);
312     g_clear_object (&seat->priv->active_session);
313     seat->priv->active_session = g_object_ref (session);
314 }
315
316 Session *
317 seat_find_session_by_login1_id (Seat *seat, const gchar *login1_session_id)
318 {
319     GList *session_link;
320
321     for (session_link = seat->priv->sessions; session_link; session_link = session_link->next)
322     {
323         Session *session = session_link->data;
324         if (g_strcmp0 (login1_session_id, session_get_login1_session_id (session)) == 0)
325             return session;
326     }
327
328     return NULL;
329 }
330
331 gboolean
332 seat_get_can_switch (Seat *seat)
333 {
334     g_return_val_if_fail (seat != NULL, FALSE);
335     return seat_get_boolean_property (seat, "allow-user-switching") && seat->priv->supports_multi_session;
336 }
337
338 gboolean
339 seat_get_allow_guest (Seat *seat)
340 {
341     g_return_val_if_fail (seat != NULL, FALSE);
342     return seat_get_boolean_property (seat, "allow-guest") && guest_account_is_installed ();
343 }
344
345 static gboolean
346 run_script (Seat *seat, DisplayServer *display_server, const gchar *script_name, User *user)
347 {
348     Process *script;
349     gboolean result = FALSE;
350
351     script = process_new (NULL, NULL);
352
353     process_set_command (script, script_name);
354
355     /* Set POSIX variables */
356     process_set_clear_environment (script, TRUE);
357     process_set_env (script, "SHELL", "/bin/sh");
358
359     /* Variables required for regression tests */
360     if (g_getenv ("LIGHTDM_TEST_ROOT"))
361     {
362         process_set_env (script, "LIGHTDM_TEST_ROOT", g_getenv ("LIGHTDM_TEST_ROOT"));
363         process_set_env (script, "LD_PRELOAD", g_getenv ("LD_PRELOAD"));
364         process_set_env (script, "LD_LIBRARY_PATH", g_getenv ("LD_LIBRARY_PATH"));
365         process_set_env (script, "PATH", g_getenv ("PATH"));
366     }
367     else
368         process_set_env (script, "PATH", "/usr/local/bin:/usr/bin:/bin");
369
370     if (user)
371     {
372         process_set_env (script, "USER", user_get_name (user));
373         process_set_env (script, "LOGNAME", user_get_name (user));
374         process_set_env (script, "HOME", user_get_home_directory (user));
375     }
376     else
377         process_set_env (script, "HOME", "/");
378
379     SEAT_GET_CLASS (seat)->run_script (seat, display_server, script);
380
381     if (process_start (script, TRUE))
382     {
383         int exit_status;
384
385         exit_status = process_get_exit_status (script);
386         if (WIFEXITED (exit_status))
387         {
388             l_debug (seat, "Exit status of %s: %d", script_name, WEXITSTATUS (exit_status));
389             result = WEXITSTATUS (exit_status) == EXIT_SUCCESS;
390         }
391     }
392
393     g_object_unref (script);
394
395     return result;
396 }
397
398 static void
399 seat_real_run_script (Seat *seat, DisplayServer *display_server, Process *process)
400 {
401 }
402
403 static void
404 emit_upstart_signal (const gchar *signal)
405 {
406     g_return_if_fail (signal != NULL);
407     g_return_if_fail (signal[0] != 0);
408     GSubprocess *p;
409
410     if (getuid () != 0)
411         return;
412
413     /* OK if it fails, probably not installed or not running upstart */
414     p = g_subprocess_new (G_SUBPROCESS_FLAGS_STDERR_SILENCE, NULL, "initctl", "-q", "emit", signal, "DISPLAY_MANAGER=lightdm", NULL);
415     g_object_unref (p);
416 }
417
418 static void
419 check_stopped (Seat *seat)
420 {
421     if (seat->priv->stopping &&
422         !seat->priv->stopped &&
423         g_list_length (seat->priv->display_servers) == 0 &&
424         g_list_length (seat->priv->sessions) == 0)
425     {
426         seat->priv->stopped = TRUE;
427         l_debug (seat, "Stopped");
428         g_signal_emit (seat, signals[STOPPED], 0);
429     }
430 }
431
432 static void
433 display_server_stopped_cb (DisplayServer *display_server, Seat *seat)
434 {
435     const gchar *script;
436     GList *list, *link;
437     Session *active_session;
438
439     l_debug (seat, "Display server stopped");
440
441     /* Run a script right after stopping the display server */
442     script = seat_get_string_property (seat, "display-stopped-script");
443     if (script)
444         run_script (seat, NULL, script, NULL);
445
446     g_signal_handlers_disconnect_matched (display_server, G_SIGNAL_MATCH_DATA, 0, 0, NULL, NULL, seat);
447     seat->priv->display_servers = g_list_remove (seat->priv->display_servers, display_server);
448
449     if (seat->priv->stopping || !seat->priv->started)
450     {
451         check_stopped (seat);
452         g_object_unref (display_server);
453         return;
454     }
455
456     /* Stop all sessions on this display server */
457     list = g_list_copy (seat->priv->sessions);
458     for (link = list; link; link = link->next)
459         g_object_ref (link->data);
460     for (link = list; link; link = link->next)
461     {
462         Session *session = link->data;
463
464         if (session_get_display_server (session) != display_server || session_get_is_stopping (session))
465             continue;
466
467         /* Stop seat if this is the only display server and it failed to start a greeter */
468         if (IS_GREETER_SESSION (session) &&
469             !session_get_is_started (session) &&
470             g_list_length (seat->priv->display_servers) == 0)
471         {
472             l_debug (seat, "Stopping; greeter display server failed to start");
473             seat_stop (seat);
474         }
475
476         l_debug (seat, "Stopping session");
477         session_stop (session);
478     }
479     g_list_free_full (list, g_object_unref);
480
481     if (!seat->priv->stopping)
482     {
483         /* If we were the active session, switch to a greeter */
484         active_session = seat_get_active_session (seat);
485         if (!active_session || session_get_display_server (active_session) == display_server)
486         {
487             l_debug (seat, "Active display server stopped, starting greeter");
488             if (!seat_switch_to_greeter (seat))
489             {
490                 l_debug (seat, "Stopping; failed to start a greeter");
491                 seat_stop (seat);
492             }
493         }
494     }
495
496     g_object_unref (display_server);
497 }
498
499 static gboolean
500 can_share_display_server (Seat *seat, DisplayServer *display_server)
501 {
502     return seat->priv->share_display_server && display_server_get_can_share (display_server);
503 }
504
505 static GreeterSession *
506 find_greeter_session (Seat *seat)
507 {
508     GList *link;
509
510     for (link = seat->priv->sessions; link; link = link->next)
511     {
512         Session *session = link->data;
513         if (!session_get_is_stopping (session) && IS_GREETER_SESSION (session))
514             return GREETER_SESSION (session);
515     }
516
517     return NULL;
518 }
519
520 static GreeterSession *
521 find_resettable_greeter (Seat *seat)
522 {
523     GList *link;
524
525     for (link = seat->priv->sessions; link; link = link->next)
526     {
527         Session *session = link->data;
528         if (!session_get_is_stopping (session) && IS_GREETER_SESSION (session) &&
529             greeter_get_resettable (greeter_session_get_greeter (GREETER_SESSION (session))))
530             return GREETER_SESSION (session);
531     }
532
533     return NULL;
534 }
535
536 static void
537 set_greeter_hints (Seat *seat, Greeter *greeter)
538 {
539     greeter_clear_hints (greeter);
540     greeter_set_hint (greeter, "default-session", seat_get_string_property (seat, "user-session"));
541     greeter_set_hint (greeter, "hide-users", seat_get_boolean_property (seat, "greeter-hide-users") ? "true" : "false");
542     greeter_set_hint (greeter, "show-manual-login", seat_get_boolean_property (seat, "greeter-show-manual-login") ? "true" : "false");
543     greeter_set_hint (greeter, "show-remote-login", seat_get_boolean_property (seat, "greeter-show-remote-login") ? "true" : "false");
544     greeter_set_hint (greeter, "has-guest-account", seat_get_allow_guest (seat) && seat_get_boolean_property (seat, "greeter-allow-guest") ? "true" : "false");
545 }
546
547 static void
548 switch_to_greeter_from_failed_session (Seat *seat, Session *session)
549 {
550     GreeterSession *greeter_session;
551     Greeter *greeter;  
552     gboolean existing = FALSE;
553
554     /* Switch to greeter if one open */
555     greeter_session = find_resettable_greeter (seat);
556     if (greeter_session)
557     {
558         l_debug (seat, "Switching to existing greeter");
559         set_greeter_hints (seat, greeter_session_get_greeter (greeter_session));
560         existing = TRUE;
561     }
562     else
563     {
564         greeter_session = create_greeter_session (seat);
565     }
566     greeter = greeter_session_get_greeter (greeter_session);
567
568     if (session_get_is_guest (session))
569         greeter_set_hint (greeter, "select-guest", "true");
570     else
571         greeter_set_hint (greeter, "select-user", session_get_username (session));
572
573     if (existing)
574     {
575         greeter_reset (greeter);
576         seat_set_active_session (seat, SESSION (greeter_session));
577     }
578     else
579     {
580         g_clear_object (&seat->priv->session_to_activate);
581         seat->priv->session_to_activate = g_object_ref (greeter_session);
582
583         if (can_share_display_server (seat, session_get_display_server (session)))
584             session_set_display_server (SESSION (greeter_session), session_get_display_server (session));
585         else
586         {
587             DisplayServer *display_server;
588
589             display_server = create_display_server (seat, session);
590             session_set_display_server (session, display_server);
591             if (!display_server_start (display_server))
592             {
593                 l_debug (seat, "Failed to start display server for greeter");
594                 seat_stop (seat);
595             }
596         }
597
598         start_session (seat, SESSION (greeter_session));
599     }
600
601     /* Stop failed session */
602     session_stop (session);
603 }
604
605 static void
606 start_session (Seat *seat, Session *session)
607 {
608     /* Use system location for greeter log file */
609     if (IS_GREETER_SESSION (session))
610     {
611         gchar *log_dir, *filename, *log_filename;
612         gboolean backup_logs;
613
614         log_dir = config_get_string (config_get_instance (), "LightDM", "log-directory");
615         filename = g_strdup_printf ("%s-greeter.log", display_server_get_name (session_get_display_server (session)));
616         log_filename = g_build_filename (log_dir, filename, NULL);
617         g_free (log_dir);
618         g_free (filename);
619         backup_logs = config_get_boolean (config_get_instance (), "LightDM", "backup-logs");
620         session_set_log_file (session, log_filename, backup_logs ? LOG_MODE_BACKUP_AND_TRUNCATE : LOG_MODE_APPEND);
621         g_free (log_filename);
622     }
623
624     if (session_start (session))
625         return;
626
627     if (IS_GREETER_SESSION (session))
628     {
629         l_debug (seat, "Failed to start greeter");
630         display_server_stop (session_get_display_server (session));
631         return;
632     }
633
634     l_debug (seat, "Failed to start session, starting greeter");
635     switch_to_greeter_from_failed_session (seat, session);
636 }
637
638 static void
639 run_session (Seat *seat, Session *session)
640 {
641     const gchar *script;
642
643     if (IS_GREETER_SESSION (session))
644         script = seat_get_string_property (seat, "greeter-setup-script");
645     else
646         script = seat_get_string_property (seat, "session-setup-script");
647     if (script && !run_script (seat, session_get_display_server (session), script, session_get_user (session)))
648     {
649         l_debug (seat, "Switching to greeter due to failed setup script");
650         switch_to_greeter_from_failed_session (seat, session);
651         return;
652     }
653
654     if (!IS_GREETER_SESSION (session))
655     {
656         g_signal_emit (seat, signals[RUNNING_USER_SESSION], 0, session);
657         emit_upstart_signal ("desktop-session-start");
658     }
659
660     session_run (session);
661
662     // FIXME: Wait until the session is ready
663
664     if (session == seat->priv->session_to_activate)
665     {
666         seat_set_active_session (seat, session);
667         g_clear_object (&seat->priv->session_to_activate);
668     }
669     else if (seat->priv->active_session)
670     {
671         /* Multiple sessions can theoretically be on the same VT (especially
672            if using Mir).  If a new session appears on an existing active VT,
673            logind will mark it as active, while ConsoleKit will re-mark the
674            oldest session as active.  In either case, that may not be the
675            session that we want to be active.  So let's be explicit and
676            re-activate the correct session whenever a new session starts.
677            There's no harm to do this in seats that enforce separate VTs. */
678         session_activate (seat->priv->active_session);
679     }
680 }
681
682 static Session *
683 find_user_session (Seat *seat, const gchar *username, Session *ignore_session)
684 {
685     GList *link;
686
687     if (!username)
688         return NULL;
689
690     for (link = seat->priv->sessions; link; link = link->next)
691     {
692         Session *session = link->data;
693
694         if (session == ignore_session)
695             continue;
696
697         if (!session_get_is_stopping (session) && g_strcmp0 (session_get_username (session), username) == 0)
698             return session;
699     }
700
701     return NULL;
702 }
703
704 static void
705 greeter_active_username_changed_cb (Greeter *greeter, GParamSpec *pspec, Seat *seat)
706 {
707     Session *session;
708
709     session = find_user_session (seat, greeter_get_active_username (greeter), seat->priv->active_session);
710
711     g_clear_object (&seat->priv->next_session);
712     seat->priv->next_session = session ? g_object_ref (session) : NULL;
713
714     SEAT_GET_CLASS (seat)->set_next_session (seat, session);
715 }
716
717 static void
718 session_authentication_complete_cb (Session *session, Seat *seat)
719 {
720     if (session_get_is_authenticated (session))
721     {
722         Session *s;
723
724         s = find_user_session (seat, session_get_username (session), session);
725         if (s)
726         {
727             l_debug (seat, "Session authenticated, switching to existing user session");
728             seat_set_active_session (seat, s);
729             session_stop (session);
730         }
731         else
732         {
733             l_debug (seat, "Session authenticated, running command");
734             run_session (seat, session);
735         }
736     }
737     else if (!IS_GREETER_SESSION (session))
738     {
739         l_debug (seat, "Switching to greeter due to failed authentication");
740         switch_to_greeter_from_failed_session (seat, session);
741     }
742     else
743     {
744         l_debug (seat, "Stopping session that failed authentication");
745         session_stop (session);
746     }
747 }
748
749 static void
750 session_stopped_cb (Session *session, Seat *seat)
751 {
752     DisplayServer *display_server;
753
754     l_debug (seat, "Session stopped");
755
756     g_signal_handlers_disconnect_matched (session, G_SIGNAL_MATCH_DATA, 0, 0, NULL, NULL, seat);
757     seat->priv->sessions = g_list_remove (seat->priv->sessions, session);
758     if (session == seat->priv->active_session)
759         g_clear_object (&seat->priv->active_session);
760     if (session == seat->priv->next_session)
761         g_clear_object (&seat->priv->next_session);
762     if (session == seat->priv->session_to_activate)
763         g_clear_object (&seat->priv->session_to_activate);
764
765     display_server = session_get_display_server (session);
766     if (!display_server)
767     {
768         g_object_unref (session);
769         return;
770     }
771
772     /* Cleanup */
773     if (!IS_GREETER_SESSION (session))
774     {
775         const gchar *script;
776         script = seat_get_string_property (seat, "session-cleanup-script");
777         if (script)
778             run_script (seat, display_server, script, session_get_user (session));
779     }
780
781     /* We were waiting for this session, but it didn't start :( */
782     // FIXME: Start a greeter on this?
783     if (session == seat->priv->session_to_activate)
784         g_clear_object (&seat->priv->session_to_activate);
785
786     if (seat->priv->stopping)
787     {
788         check_stopped (seat);
789         g_object_unref (session);
790         return;
791     }
792     
793     /* If there is a pending replacement greeter, start it */
794     if (IS_GREETER_SESSION (session) && seat->priv->replacement_greeter)
795     {
796         GreeterSession *replacement_greeter = seat->priv->replacement_greeter;
797         seat->priv->replacement_greeter = NULL;
798         
799         if (session_get_is_authenticated (SESSION (replacement_greeter)))
800         {
801             l_debug (seat, "Greeter stopped, running session");
802             run_session (seat, SESSION (replacement_greeter));
803         }
804         else
805         {
806             l_debug (seat, "Greeter stopped, starting session authentication");
807             start_session (seat, SESSION (replacement_greeter));
808         }
809
810         g_object_unref (replacement_greeter);
811     }
812     /* If this is the greeter session then re-use this display server */
813     else if (IS_GREETER_SESSION (session) &&
814         can_share_display_server (seat, display_server) &&
815         greeter_get_start_session (greeter_session_get_greeter (GREETER_SESSION (session))))
816     {
817         GList *link;
818
819         for (link = seat->priv->sessions; link; link = link->next)
820         {
821             Session *s = link->data;
822
823             /* Skip this session and sessions on other display servers */
824             if (s == session || session_get_display_server (s) != display_server || session_get_is_stopping (s))
825                 continue;
826
827             if (session_get_is_authenticated (s))
828             {
829                 l_debug (seat, "Greeter stopped, running session");
830                 run_session (seat, s);
831             }
832             else
833             {
834                 l_debug (seat, "Greeter stopped, starting session authentication");
835                 start_session (seat, s);
836             }
837             break;
838         }
839     }
840     /* If this is the greeter and nothing else is running then stop the seat */
841     else if (IS_GREETER_SESSION (session) &&
842         !greeter_get_start_session (greeter_session_get_greeter (GREETER_SESSION (session))) &&
843         g_list_length (seat->priv->display_servers) == 1 &&
844         g_list_nth_data (seat->priv->display_servers, 0) == display_server)
845     {
846         l_debug (seat, "Stopping; failed to start a greeter");
847         seat_stop (seat);
848     }
849     /* If we were the active session, switch to a greeter */
850     else if (!IS_GREETER_SESSION (session) && session == seat_get_active_session (seat))
851     {
852         l_debug (seat, "Active session stopped, starting greeter");
853         if (!seat_switch_to_greeter (seat))
854         {
855             l_debug (seat, "Stopping; failed to start a greeter");
856             seat_stop (seat);
857         }
858     }
859
860     /* Stop the display server if no-longer required */
861     if (display_server && !display_server_get_is_stopping (display_server))
862     {
863         GList *link;
864         int n_sessions = 0;
865
866         for (link = seat->priv->sessions; link; link = link->next)
867         {
868             Session *s = link->data;
869             if (s == session)
870                 continue;
871             if (session_get_display_server (s) == display_server)
872                 n_sessions++;
873         }
874         if (n_sessions == 0)
875         {
876             l_debug (seat, "Stopping display server, no sessions require it");
877             display_server_stop (display_server);
878         }
879     }
880
881     g_signal_emit (seat, signals[SESSION_REMOVED], 0, session);
882     g_object_unref (session);
883 }
884
885 static void
886 set_session_env (Session *session)
887 {
888     /* Connect using the session bus */
889     if (getuid () != 0)
890     {
891         if (g_getenv ("DBUS_SESSION_BUS_ADDRESS"))
892             session_set_env (session, "DBUS_SESSION_BUS_ADDRESS", g_getenv ("DBUS_SESSION_BUS_ADDRESS"));
893         session_set_env (session, "LDM_BUS", "SESSION");
894         if (g_getenv ("LD_PRELOAD"))
895             session_set_env (session, "LD_PRELOAD", g_getenv ("LD_PRELOAD"));
896         if (g_getenv ("LD_LIBRARY_PATH"))
897             session_set_env (session, "LD_LIBRARY_PATH", g_getenv ("LD_LIBRARY_PATH"));
898         if (g_getenv ("PATH"))
899             session_set_env (session, "PATH", g_getenv ("PATH"));
900     }
901
902     /* Variables required for regression tests */
903     if (g_getenv ("LIGHTDM_TEST_ROOT"))
904     {
905         session_set_env (session, "LIGHTDM_TEST_ROOT", g_getenv ("LIGHTDM_TEST_ROOT"));
906         session_set_env (session, "DBUS_SYSTEM_BUS_ADDRESS", g_getenv ("DBUS_SYSTEM_BUS_ADDRESS"));
907         session_set_env (session, "DBUS_SESSION_BUS_ADDRESS", g_getenv ("DBUS_SESSION_BUS_ADDRESS"));
908         session_set_env (session, "LD_PRELOAD", g_getenv ("LD_PRELOAD"));
909         session_set_env (session, "LD_LIBRARY_PATH", g_getenv ("LD_LIBRARY_PATH"));
910         session_set_env (session, "GI_TYPELIB_PATH", g_getenv ("GI_TYPELIB_PATH"));
911     }
912 }
913
914 static Session *
915 create_session (Seat *seat, gboolean autostart)
916 {
917     Session *session;
918
919     session = SEAT_GET_CLASS (seat)->create_session (seat);
920     seat->priv->sessions = g_list_append (seat->priv->sessions, session);
921     if (autostart)
922         g_signal_connect (session, SESSION_SIGNAL_AUTHENTICATION_COMPLETE, G_CALLBACK (session_authentication_complete_cb), seat);
923     g_signal_connect (session, SESSION_SIGNAL_STOPPED, G_CALLBACK (session_stopped_cb), seat);
924
925     set_session_env (session);
926
927     g_signal_emit (seat, signals[SESSION_ADDED], 0, session);
928
929     return session;
930 }
931
932 static gchar **
933 get_session_argv (Seat *seat, SessionConfig *session_config, const gchar *session_wrapper)
934 {
935     gboolean result;
936     int argc;
937     gchar **argv, *path;
938     GError *error = NULL;
939
940     /* If configured, run sessions through a wrapper */
941     if (session_wrapper)
942     {
943         argv = g_malloc (sizeof (gchar *) * 3);
944         path = g_find_program_in_path (session_wrapper);
945         argv[0] = path ? path : g_strdup (session_wrapper);
946         argv[1] = g_strdup (session_config_get_command (session_config));
947         argv[2] = NULL;
948         return argv;
949     }
950
951     /* Split command into an array listing and make command absolute */
952     result = g_shell_parse_argv (session_config_get_command (session_config), &argc, &argv, &error);
953     if (error)
954         l_debug (seat, "Invalid session command '%s': %s", session_config_get_command (session_config), error->message);
955     g_clear_error (&error);
956     if (!result)
957         return NULL;
958     path = g_find_program_in_path (argv[0]);
959     if (path)
960     {
961         g_free (argv[0]);
962         argv[0] = path;
963     }
964
965     return argv;
966 }
967
968 static SessionConfig *
969 find_session_config (Seat *seat, const gchar *sessions_dir, const gchar *session_name)
970 {
971     gchar **dirs;
972     SessionConfig *session_config = NULL;
973     int i;
974     GError *error = NULL;
975
976     g_return_val_if_fail (sessions_dir != NULL, NULL);
977     g_return_val_if_fail (session_name != NULL, NULL);
978
979     dirs = g_strsplit (sessions_dir, ":", -1);
980     for (i = 0; dirs[i]; i++)
981     {
982         gchar *filename, *path;
983         const gchar *default_session_type = "x";
984
985         if (strcmp (dirs[i], WAYLAND_SESSIONS_DIR) == 0)
986             default_session_type = "wayland";
987
988         filename = g_strdup_printf ("%s.desktop", session_name);
989         path = g_build_filename (dirs[i], filename, NULL);
990         g_free (filename);
991         session_config = session_config_new_from_file (path, default_session_type, &error);
992         g_free (path);
993         if (session_config)
994             break;
995
996         if (dirs[i+1] == NULL)
997             l_debug (seat, "Failed to find session configuration %s", session_name);
998         g_clear_error (&error);
999     }
1000     g_strfreev (dirs);
1001
1002     return session_config;
1003 }
1004
1005 static void
1006 configure_session (Session *session, SessionConfig *config, const gchar *session_name, const gchar *language)
1007 {
1008     gchar **desktop_names;
1009
1010     session_set_config (session, config);
1011     session_set_env (session, "XDG_SESSION_DESKTOP", session_name);
1012     session_set_env (session, "DESKTOP_SESSION", session_name);
1013     session_set_env (session, "GDMSESSION", session_name);
1014     desktop_names = session_config_get_desktop_names (config);
1015     if (desktop_names)
1016     {
1017         gchar *value;
1018         value = g_strjoinv (":", desktop_names);
1019         session_set_env (session, "XDG_CURRENT_DESKTOP", value);
1020         g_free (value);
1021     }
1022     if (language && language[0] != '\0')
1023     {
1024         session_set_env (session, "LANG", language);
1025         session_set_env (session, "GDM_LANG", language);
1026     }
1027 }
1028
1029 static Session *
1030 create_user_session (Seat *seat, const gchar *username, gboolean autostart)
1031 {
1032     User *user;
1033     gchar *sessions_dir;
1034     const gchar *session_name, *language;
1035     SessionConfig *session_config;
1036     Session *session = NULL;
1037
1038     l_debug (seat, "Creating user session");
1039
1040     /* Load user preferences */
1041     user = accounts_get_user_by_name (username);
1042     if (!user)
1043     {
1044         l_debug (seat, "Can't login unknown user '%s'", username);
1045         return NULL;
1046     }
1047     session_name = user_get_xsession (user);
1048     language = user_get_language (user);
1049
1050     /* Override session for autologin if configured */
1051     if (autostart)
1052     {
1053         const gchar *autologin_session_name = seat_get_string_property (seat, "autologin-session");
1054         if (autologin_session_name)
1055             session_name = autologin_session_name;
1056     }
1057
1058     if (!session_name)
1059         session_name = seat_get_string_property (seat, "user-session");
1060     sessions_dir = config_get_string (config_get_instance (), "LightDM", "sessions-directory");
1061     session_config = find_session_config (seat, sessions_dir, session_name);
1062     g_free (sessions_dir);
1063     if (session_config)
1064     {
1065         gchar **argv;
1066
1067         session = create_session (seat, autostart);
1068         configure_session (session, session_config, session_name, language);
1069         session_set_username (session, username);
1070         session_set_do_authenticate (session, TRUE);
1071         argv = get_session_argv (seat, session_config, seat_get_string_property (seat, "session-wrapper"));
1072         session_set_argv (session, argv);
1073         g_strfreev (argv);
1074         g_object_unref (session_config);
1075     }
1076     else
1077         l_debug (seat, "Can't find session '%s'", session_name);
1078
1079     g_object_unref (user);
1080
1081     return session;
1082 }
1083
1084 static void
1085 prepend_argv (gchar ***argv, const gchar *value)
1086 {
1087     gchar **old_argv, **new_argv;
1088     gint i;
1089
1090     old_argv = *argv;
1091     new_argv = g_malloc (sizeof (gchar *) * (g_strv_length (*argv) + 2));
1092     new_argv[0] = g_strdup (value);
1093     for (i = 0; old_argv[i]; i++)
1094         new_argv[i + 1] = old_argv[i];
1095     new_argv[i + 1] = NULL;
1096
1097     g_free (*argv);
1098     *argv = new_argv;
1099 }
1100
1101 static Session *
1102 create_guest_session (Seat *seat, const gchar *session_name)
1103 {
1104     const gchar *guest_wrapper;
1105     gchar *sessions_dir, **argv;
1106     SessionConfig *session_config;
1107     Session *session;
1108
1109     if (!session_name)
1110         session_name = seat_get_string_property (seat, "guest-session");
1111     if (!session_name)
1112         session_name = seat_get_string_property (seat, "user-session");
1113     sessions_dir = config_get_string (config_get_instance (), "LightDM", "sessions-directory");
1114     session_config = find_session_config (seat, sessions_dir, session_name);
1115     g_free (sessions_dir);
1116     if (!session_config)
1117     {
1118         l_debug (seat, "Can't find session '%s'", session_name);
1119         return NULL;
1120     }
1121
1122     session = create_session (seat, TRUE);
1123     configure_session (session, session_config, session_name, NULL);
1124     session_set_do_authenticate (session, TRUE);
1125     session_set_is_guest (session, TRUE);
1126     argv = get_session_argv (seat, session_config, seat_get_string_property (seat, "session-wrapper"));
1127     guest_wrapper = seat_get_string_property (seat, "guest-wrapper");
1128     if (guest_wrapper)
1129     {
1130         gchar *path;
1131         path = g_find_program_in_path (guest_wrapper);
1132         prepend_argv (&argv, path ? path : guest_wrapper);
1133         g_free (path);
1134     }
1135
1136     session_set_argv (session, argv);
1137     g_strfreev (argv);
1138     g_object_unref (session_config);
1139
1140     return session;
1141 }
1142
1143 // FIXME: This is inefficient and we already know the greeter session when we set the callbacks...
1144 static Session *
1145 get_greeter_session (Seat *seat, Greeter *greeter)
1146 {
1147     GList *link;
1148
1149     /* Stop any greeters */
1150     for (link = seat->priv->sessions; link; link = link->next)
1151     {
1152         Session *session = link->data;
1153
1154         if (IS_GREETER_SESSION (session) && greeter_session_get_greeter (GREETER_SESSION (session)))
1155             return session;
1156     }
1157
1158     return NULL;
1159 }
1160
1161 static Session *
1162 greeter_create_session_cb (Greeter *greeter, Seat *seat)
1163 {
1164     Session *greeter_session, *session;
1165
1166     greeter_session = get_greeter_session (seat, greeter);
1167     session = create_session (seat, FALSE);
1168     session_set_config (session, session_get_config (greeter_session));
1169     session_set_display_server (session, session_get_display_server (greeter_session));
1170
1171     return g_object_ref (session);
1172 }
1173
1174 static gboolean
1175 greeter_start_session_cb (Greeter *greeter, SessionType type, const gchar *session_name, Seat *seat)
1176 {
1177     Session *session, *existing_session, *greeter_session;
1178     const gchar *username;
1179     DisplayServer *display_server;
1180
1181     /* Get the session to use */
1182     if (greeter_get_guest_authenticated (greeter))
1183     {
1184         session = create_guest_session (seat, session_name);
1185         if (!session)
1186             return FALSE;
1187         session_set_pam_service (session, seat_get_string_property (seat, "pam-autologin-service"));
1188     }
1189     else
1190     {
1191         const gchar *language = NULL;
1192         SessionConfig *session_config;
1193         User *user;
1194         gchar *sessions_dir = NULL;
1195         gchar **argv;
1196
1197         session = greeter_get_authentication_session (greeter);
1198
1199         /* Get session command to run */
1200         switch (type)
1201         {
1202         case SESSION_TYPE_LOCAL:
1203             sessions_dir = config_get_string (config_get_instance (), "LightDM", "sessions-directory");
1204             break;
1205         case SESSION_TYPE_REMOTE:
1206             sessions_dir = config_get_string (config_get_instance (), "LightDM", "remote-sessions-directory");
1207             break;
1208         }
1209
1210         /* Load user preferences */
1211         user = session_get_user (session);
1212         if (user)
1213         {
1214             if (!session_name)
1215                 session_name = user_get_xsession (user);
1216             language = user_get_language (user);
1217         }
1218
1219         if (!session_name)
1220             session_name = seat_get_string_property (seat, "user-session");
1221         if (user)
1222             user_set_xsession (session_get_user (session), session_name);
1223
1224         session_config = find_session_config (seat, sessions_dir, session_name);
1225         g_free (sessions_dir);
1226         if (!session_config)
1227         {
1228             l_debug (seat, "Can't find session '%s'", session_name);
1229             return FALSE;
1230         }
1231
1232         configure_session (session, session_config, session_name, language);
1233         argv = get_session_argv (seat, session_config, seat_get_string_property (seat, "session-wrapper"));
1234         session_set_argv (session, argv);
1235         g_strfreev (argv);
1236         g_object_unref (session_config);
1237     }
1238
1239     /* Switch to this session when it is ready */
1240     g_clear_object (&seat->priv->session_to_activate);
1241     seat->priv->session_to_activate = g_object_ref (session);
1242
1243     /* Return to existing session if it is open */
1244     username = session_get_username (session);
1245     existing_session = find_user_session (seat, username, NULL);
1246     if (existing_session && session != existing_session)
1247     {
1248         l_debug (seat, "Returning to existing user session %s", username);
1249         session_stop (session);
1250         session_unlock (existing_session);
1251         seat_set_active_session (seat, existing_session);
1252         return TRUE;
1253     }
1254
1255     /* If can re-use the display server, stop the greeter first */
1256     greeter_session = get_greeter_session (seat, greeter);
1257     display_server = session_get_display_server (greeter_session);
1258     if (!greeter_get_resettable (greeter) &&
1259         can_share_display_server (seat, display_server) &&
1260         strcmp (display_server_get_session_type (display_server), session_get_session_type (session)) == 0)
1261     {
1262         l_debug (seat, "Stopping greeter; display server will be re-used for user session");
1263
1264         /* Run on the same display server after the greeter has stopped */
1265         session_set_display_server (session, display_server);
1266
1267         /* Stop the greeter */
1268         session_stop (greeter_session);
1269
1270         return TRUE;
1271     }
1272     /* Otherwise start a new display server for this session */
1273     else
1274     {
1275         display_server = create_display_server (seat, session);
1276         session_set_display_server (session, display_server);
1277         if (!display_server_start (display_server))
1278         {
1279             l_debug (seat, "Failed to start display server for new session");
1280             return FALSE;
1281         }
1282
1283         return TRUE;
1284     }
1285 }
1286
1287 static GreeterSession *
1288 create_greeter_session (Seat *seat)
1289 {
1290     gchar *sessions_dir, **argv;
1291     SessionConfig *session_config;
1292     GreeterSession *greeter_session;
1293     Greeter *greeter;  
1294     const gchar *greeter_wrapper;
1295     const gchar *autologin_username;
1296     int autologin_timeout;
1297     gboolean autologin_guest;
1298
1299     l_debug (seat, "Creating greeter session");
1300
1301     sessions_dir = config_get_string (config_get_instance (), "LightDM", "greeters-directory");
1302     session_config = find_session_config (seat, sessions_dir, seat_get_string_property (seat, "greeter-session"));
1303     g_free (sessions_dir);
1304     if (!session_config)
1305         return NULL;
1306
1307     argv = get_session_argv (seat, session_config, NULL);
1308     greeter_wrapper = seat_get_string_property (seat, "greeter-wrapper");
1309     if (greeter_wrapper)
1310     {
1311         gchar *path;
1312         path = g_find_program_in_path (greeter_wrapper);
1313         prepend_argv (&argv, path ? path : greeter_wrapper);
1314         g_free (path);
1315     }
1316
1317     greeter_session = SEAT_GET_CLASS (seat)->create_greeter_session (seat);
1318     greeter = greeter_session_get_greeter (greeter_session);
1319     session_set_config (SESSION (greeter_session), session_config);
1320     seat->priv->sessions = g_list_append (seat->priv->sessions, SESSION (greeter_session));
1321     g_signal_connect (greeter, GREETER_SIGNAL_ACTIVE_USERNAME_CHANGED, G_CALLBACK (greeter_active_username_changed_cb), seat);
1322     g_signal_connect (greeter_session, SESSION_SIGNAL_AUTHENTICATION_COMPLETE, G_CALLBACK (session_authentication_complete_cb), seat);
1323     g_signal_connect (greeter_session, SESSION_SIGNAL_STOPPED, G_CALLBACK (session_stopped_cb), seat);
1324
1325     set_session_env (SESSION (greeter_session));
1326     session_set_env (SESSION (greeter_session), "XDG_SESSION_CLASS", "greeter");
1327
1328     session_set_pam_service (SESSION (greeter_session), seat_get_string_property (seat, "pam-greeter-service"));
1329     if (getuid () == 0)
1330     {
1331         gchar *greeter_user;
1332         greeter_user = config_get_string (config_get_instance (), "LightDM", "greeter-user");
1333         session_set_username (SESSION (greeter_session), greeter_user);
1334         g_free (greeter_user);
1335     }
1336     else
1337     {
1338         /* In test mode run the greeter as ourself */
1339         session_set_username (SESSION (greeter_session), user_get_name (accounts_get_current_user ()));
1340     }
1341     session_set_argv (SESSION (greeter_session), argv);
1342     g_strfreev (argv);
1343
1344     greeter_set_pam_services (greeter,
1345                               seat_get_string_property (seat, "pam-service"),
1346                               seat_get_string_property (seat, "pam-autologin-service"));
1347     g_signal_connect (greeter, GREETER_SIGNAL_CREATE_SESSION, G_CALLBACK (greeter_create_session_cb), seat);
1348     g_signal_connect (greeter, GREETER_SIGNAL_START_SESSION, G_CALLBACK (greeter_start_session_cb), seat);
1349
1350     /* Set hints to greeter */
1351     greeter_set_allow_guest (greeter, seat_get_allow_guest (seat));
1352     set_greeter_hints (seat, greeter);
1353
1354     /* Configure for automatic login */
1355     autologin_username = seat_get_string_property (seat, "autologin-user");
1356     if (g_strcmp0 (autologin_username, "") == 0)
1357         autologin_username = NULL;
1358     autologin_timeout = seat_get_integer_property (seat, "autologin-user-timeout");
1359     autologin_guest = seat_get_boolean_property (seat, "autologin-guest");
1360     if (autologin_timeout > 0)
1361     {
1362         gchar *value;
1363
1364         value = g_strdup_printf ("%d", autologin_timeout);
1365         greeter_set_hint (greeter, "autologin-timeout", value);
1366         g_free (value);
1367         if (autologin_username)
1368             greeter_set_hint (greeter, "autologin-user", autologin_username);
1369         if (autologin_guest)
1370             greeter_set_hint (greeter, "autologin-guest", "true");
1371     }
1372
1373     g_object_unref (session_config);
1374
1375     return greeter_session;
1376 }
1377
1378 static Session *
1379 find_session_for_display_server (Seat *seat, DisplayServer *display_server)
1380 {
1381     GList *link;
1382
1383     for (link = seat->priv->sessions; link; link = link->next)
1384     {
1385         Session *session = link->data;
1386         if (session_get_display_server (session) == display_server && !session_get_is_stopping (session))
1387             return session;
1388     }
1389
1390     return NULL;
1391 }
1392
1393 static void
1394 display_server_ready_cb (DisplayServer *display_server, Seat *seat)
1395 {
1396     const gchar *script;
1397     Session *session;
1398
1399     /* Run setup script */
1400     script = seat_get_string_property (seat, "display-setup-script");
1401     if (script && !run_script (seat, display_server, script, NULL))
1402     {
1403         l_debug (seat, "Stopping display server due to failed setup script");
1404         display_server_stop (display_server);
1405         return;
1406     }
1407
1408     emit_upstart_signal ("login-session-start");
1409
1410     /* Start the session waiting for this display server */
1411     session = find_session_for_display_server (seat, display_server);
1412     if (session)
1413     {
1414         if (session_get_is_authenticated (session))
1415         {
1416             l_debug (seat, "Display server ready, running session");
1417             run_session (seat, session);
1418         }
1419         else
1420         {
1421             l_debug (seat, "Display server ready, starting session authentication");
1422             start_session (seat, session);
1423         }
1424     }
1425     else
1426     {
1427         l_debug (seat, "Stopping not required display server");
1428         display_server_stop (display_server);
1429     }
1430 }
1431
1432 static DisplayServer *
1433 create_display_server (Seat *seat, Session *session)
1434 {
1435     DisplayServer *display_server;
1436
1437     l_debug (seat, "Creating display server of type %s", session_get_session_type (session));
1438
1439     display_server = SEAT_GET_CLASS (seat)->create_display_server (seat, session);
1440     if (!display_server)
1441         return NULL;
1442
1443     seat->priv->display_servers = g_list_append (seat->priv->display_servers, display_server);
1444     g_signal_connect (display_server, DISPLAY_SERVER_SIGNAL_READY, G_CALLBACK (display_server_ready_cb), seat);
1445     g_signal_connect (display_server, DISPLAY_SERVER_SIGNAL_STOPPED, G_CALLBACK (display_server_stopped_cb), seat);
1446
1447     return display_server;
1448 }
1449
1450 gboolean
1451 seat_switch_to_greeter (Seat *seat)
1452 {
1453     GreeterSession *greeter_session;
1454     DisplayServer *display_server;
1455
1456     g_return_val_if_fail (seat != NULL, FALSE);
1457
1458     if (!seat_get_can_switch (seat))
1459         return FALSE;
1460
1461     /* Switch to greeter if one open */
1462     greeter_session = find_greeter_session (seat);
1463     if (greeter_session)
1464     {
1465         l_debug (seat, "Switching to existing greeter");
1466         seat_set_active_session (seat, SESSION (greeter_session));
1467         return TRUE;
1468     }
1469
1470     greeter_session = create_greeter_session (seat);
1471     if (!greeter_session)
1472         return FALSE;
1473
1474     g_clear_object (&seat->priv->session_to_activate);
1475     seat->priv->session_to_activate = g_object_ref (greeter_session);
1476
1477     display_server = create_display_server (seat, SESSION (greeter_session));
1478     session_set_display_server (SESSION (greeter_session), display_server);
1479
1480     return display_server_start (display_server);
1481 }
1482
1483 static void
1484 switch_authentication_complete_cb (Session *session, Seat *seat)
1485 {
1486     GreeterSession *greeter_session;
1487     Greeter *greeter;
1488     DisplayServer *display_server;
1489     gboolean existing = FALSE;
1490
1491     /* If authenticated, then unlock existing session or start new one */
1492     if (session_get_is_authenticated (session))
1493     {
1494         Session *s;
1495
1496         s = find_user_session (seat, session_get_username (session), session);
1497         if (s)
1498         {
1499             l_debug (seat, "Session authenticated, switching to existing user session");
1500             session_unlock (s);
1501             seat_set_active_session (seat, s);
1502             session_stop (session);
1503         }
1504         else
1505         {
1506             l_debug (seat, "Session authenticated, starting display server");
1507             g_clear_object (&seat->priv->session_to_activate);
1508             seat->priv->session_to_activate = g_object_ref (session);
1509             display_server = create_display_server (seat, session);
1510             session_set_display_server (session, display_server);
1511             display_server_start (display_server);
1512         }
1513
1514         return;
1515     }
1516
1517     session_stop (session);
1518
1519     /* See if we already have a greeter up and reuse it if so */
1520     greeter_session = find_resettable_greeter (seat);
1521     if (greeter_session)
1522     {
1523         l_debug (seat, "Switching to existing greeter to authenticate session");
1524         set_greeter_hints (seat, greeter_session_get_greeter (greeter_session));
1525         existing = TRUE;
1526     }
1527     else
1528     {
1529         l_debug (seat, "Starting greeter to authenticate session");
1530         greeter_session = create_greeter_session (seat);
1531     }
1532     greeter = greeter_session_get_greeter (greeter_session);
1533
1534     if (session_get_is_guest (session))
1535         greeter_set_hint (greeter, "select-guest", "true");
1536     else
1537         greeter_set_hint (greeter, "select-user", session_get_username (session));
1538
1539     if (existing)
1540     {
1541         greeter_reset (greeter);
1542         seat_set_active_session (seat, SESSION (greeter_session));
1543     }
1544     else
1545     {
1546         g_clear_object (&seat->priv->session_to_activate);
1547         seat->priv->session_to_activate = g_object_ref (greeter_session);
1548
1549         display_server = create_display_server (seat, SESSION (greeter_session));
1550         session_set_display_server (SESSION (greeter_session), display_server);
1551         display_server_start (display_server);
1552     }
1553 }
1554
1555 gboolean
1556 seat_switch_to_user (Seat *seat, const gchar *username, const gchar *session_name)
1557 {
1558     Session *session;
1559
1560     g_return_val_if_fail (seat != NULL, FALSE);
1561     g_return_val_if_fail (username != NULL, FALSE);
1562
1563     if (!seat_get_can_switch (seat))
1564         return FALSE;
1565
1566     /* If we're already on this session, then ignore */
1567     session = find_user_session (seat, username, NULL);
1568     if (session && session == seat->priv->active_session)
1569         return TRUE;
1570
1571     l_debug (seat, "Switching to user %s", username);
1572
1573     /* Attempt to authenticate them */
1574     session = create_user_session (seat, username, FALSE);
1575     g_signal_connect (session, SESSION_SIGNAL_AUTHENTICATION_COMPLETE, G_CALLBACK (switch_authentication_complete_cb), seat);
1576     session_set_pam_service (session, seat_get_string_property (seat, "pam-service"));
1577
1578     return session_start (session);
1579 }
1580
1581 static Session *
1582 find_guest_session (Seat *seat)
1583 {
1584     GList *link;
1585
1586     for (link = seat->priv->sessions; link; link = link->next)
1587     {
1588         Session *session = link->data;
1589         if (!session_get_is_stopping (session) && session_get_is_guest (session))
1590             return session;
1591     }
1592
1593     return NULL;
1594 }
1595
1596 gboolean
1597 seat_switch_to_guest (Seat *seat, const gchar *session_name)
1598 {
1599     Session *session;
1600     DisplayServer *display_server;
1601
1602     g_return_val_if_fail (seat != NULL, FALSE);
1603
1604     if (!seat_get_can_switch (seat) || !seat_get_allow_guest (seat))
1605         return FALSE;
1606
1607     /* Switch to session if one open */
1608     session = find_guest_session (seat);
1609     if (session)
1610     {
1611         l_debug (seat, "Switching to existing guest account %s", session_get_username (session));
1612         seat_set_active_session (seat, session);
1613         return TRUE;
1614     }
1615
1616     session = create_guest_session (seat, session_name);
1617     if (!session)
1618         return FALSE;
1619
1620     display_server = create_display_server (seat, session);
1621
1622     g_clear_object (&seat->priv->session_to_activate);
1623     seat->priv->session_to_activate = g_object_ref (session);
1624     session_set_pam_service (session, seat_get_string_property (seat, "pam-autologin-service"));
1625     session_set_display_server (session, display_server);
1626
1627     return display_server_start (display_server);
1628 }
1629
1630 gboolean
1631 seat_lock (Seat *seat, const gchar *username)
1632 {
1633     GreeterSession *greeter_session;
1634     Greeter *greeter;
1635     DisplayServer *display_server = NULL;
1636     gboolean reset_existing = FALSE;
1637     gboolean reuse_xserver = FALSE;
1638
1639     g_return_val_if_fail (seat != NULL, FALSE);
1640
1641     if (!seat_get_can_switch (seat))
1642         return FALSE;
1643
1644     // FIXME: If already locked then don't bother...
1645
1646     l_debug (seat, "Locking");
1647
1648     /* Switch to greeter we can reuse */
1649     greeter_session = find_resettable_greeter (seat);
1650     if (greeter_session)
1651     {
1652         l_debug (seat, "Switching to existing greeter");
1653         set_greeter_hints (seat, greeter_session_get_greeter (greeter_session));
1654         reset_existing = TRUE;
1655     }
1656     else
1657     {
1658         /* If the existing greeter can't be reused, stop it and reuse its display server */
1659         greeter_session = find_greeter_session (seat);
1660         if (greeter_session)
1661         {
1662             display_server = session_get_display_server (SESSION (greeter_session));
1663             if (!session_get_is_stopping (SESSION (greeter_session)))
1664             {
1665                 l_debug (seat, "Stopping session");
1666                 session_stop (SESSION (greeter_session));
1667             }
1668             reuse_xserver = TRUE;
1669         }
1670         
1671         greeter_session = create_greeter_session (seat);
1672         if (!greeter_session)
1673             return FALSE;
1674     }
1675     greeter = greeter_session_get_greeter (greeter_session);
1676
1677     greeter_set_hint (greeter, "lock-screen", "true");
1678     if (username)
1679         greeter_set_hint (greeter, "select-user", username);
1680
1681     if (reset_existing)
1682     {
1683         greeter_reset (greeter);
1684         seat_set_active_session (seat, SESSION (greeter_session));
1685         return TRUE;
1686     }
1687     else
1688     {
1689         if (!reuse_xserver)
1690             display_server = create_display_server (seat, SESSION (greeter_session));
1691         session_set_display_server (SESSION (greeter_session), display_server);
1692
1693         g_clear_object (&seat->priv->session_to_activate);
1694         seat->priv->session_to_activate = g_object_ref (greeter_session);
1695
1696         if (reuse_xserver)
1697         {
1698             g_clear_object (&seat->priv->replacement_greeter);
1699             seat->priv->replacement_greeter = g_object_ref (greeter_session);
1700             return TRUE;
1701         }
1702         else
1703             return display_server_start (display_server);
1704     }
1705 }
1706
1707 void
1708 seat_stop (Seat *seat)
1709 {
1710     g_return_if_fail (seat != NULL);
1711
1712     if (seat->priv->stopping)
1713         return;
1714
1715     l_debug (seat, "Stopping");
1716     seat->priv->stopping = TRUE;
1717     SEAT_GET_CLASS (seat)->stop (seat);
1718 }
1719
1720 gboolean
1721 seat_get_is_stopping (Seat *seat)
1722 {
1723     g_return_val_if_fail (seat != NULL, FALSE);
1724     return seat->priv->stopping;
1725 }
1726
1727 static void
1728 seat_real_setup (Seat *seat)
1729 {
1730 }
1731
1732 static gboolean
1733 seat_real_start (Seat *seat)
1734 {
1735     const gchar *autologin_username;
1736     int autologin_timeout;
1737     gboolean autologin_guest;
1738     gboolean autologin_in_background;
1739     Session *session = NULL, *background_session = NULL;
1740
1741     /* Get autologin settings */
1742     autologin_username = seat_get_string_property (seat, "autologin-user");
1743     if (g_strcmp0 (autologin_username, "") == 0)
1744         autologin_username = NULL;
1745     autologin_timeout = seat_get_integer_property (seat, "autologin-user-timeout");
1746     autologin_guest = seat_get_boolean_property (seat, "autologin-guest");
1747     autologin_in_background = seat_get_boolean_property (seat, "autologin-in-background");
1748
1749     /* Autologin if configured */
1750     if (autologin_timeout == 0 || autologin_in_background)
1751     {
1752         if (autologin_guest)
1753             session = create_guest_session (seat, NULL);
1754         else if (autologin_username != NULL)
1755             session = create_user_session (seat, autologin_username, TRUE);
1756
1757         if (session)
1758             session_set_pam_service (session, seat_get_string_property (seat, "pam-autologin-service"));
1759
1760         /* Load in background if required */
1761         if (autologin_in_background && session)
1762         {
1763             background_session = session;
1764             session = NULL;
1765         }
1766
1767         if (session)
1768         {
1769             DisplayServer *display_server;
1770
1771             g_clear_object (&seat->priv->session_to_activate);
1772             seat->priv->session_to_activate = g_object_ref (session);
1773
1774             display_server = create_display_server (seat, session);
1775             session_set_display_server (session, display_server);
1776             if (!display_server || !display_server_start (display_server))
1777             {
1778                 l_debug (seat, "Can't create display server for automatic login");
1779                 session_stop (session);
1780                 if (display_server)
1781                     display_server_stop (display_server);
1782                 session = NULL;
1783             }
1784         }
1785     }
1786
1787     /* Fallback to a greeter */
1788     if (!session)
1789     {
1790         GreeterSession *greeter_session;
1791         DisplayServer *display_server;
1792
1793         greeter_session = create_greeter_session (seat);
1794         if (!greeter_session)
1795         {
1796             l_debug (seat, "Failed to create greeter session");
1797             return FALSE;
1798         }
1799
1800         g_clear_object (&seat->priv->session_to_activate);
1801         seat->priv->session_to_activate = g_object_ref (greeter_session);
1802         session = SESSION (greeter_session);
1803
1804         display_server = create_display_server (seat, session);
1805         session_set_display_server (session, display_server);
1806         if (!display_server || !display_server_start (display_server))
1807         {
1808             l_debug (seat, "Can't create display server for greeter");
1809             session_stop (session);
1810             if (display_server)
1811                 display_server_stop (display_server);
1812             session = NULL;
1813         }
1814     }
1815
1816     /* Fail if can't start a session */
1817     if (!session)
1818     {
1819         seat_stop (seat);
1820         return FALSE;
1821     }
1822
1823     /* Start background session */
1824     if (background_session)
1825     {
1826         DisplayServer *background_display_server;
1827
1828         background_display_server = create_display_server (seat, background_session);
1829         session_set_display_server (background_session, background_display_server);
1830         if (!display_server_start (background_display_server))
1831             l_warning (seat, "Failed to start display server for background session");
1832     }
1833
1834     return TRUE;
1835 }
1836
1837 static GreeterSession *
1838 seat_real_create_greeter_session (Seat *seat)
1839 {
1840     return greeter_session_new ();
1841 }
1842
1843 static Session *
1844 seat_real_create_session (Seat *seat)
1845 {
1846     return session_new ();
1847 }
1848
1849 static void
1850 seat_real_set_active_session (Seat *seat, Session *session)
1851 {
1852 }
1853
1854 static void
1855 seat_real_set_next_session (Seat *seat, Session *session)
1856 {
1857 }
1858
1859 static Session *
1860 seat_real_get_active_session (Seat *seat)
1861 {
1862     return NULL;
1863 }
1864
1865 static void
1866 seat_real_stop (Seat *seat)
1867 {
1868     GList *list, *link;
1869
1870     check_stopped (seat);
1871     if (seat->priv->stopped)
1872         return;
1873
1874     /* Stop all the display servers and sessions on the seat. Copy the list as
1875      * it might be modified if a display server / session stops during this loop */
1876     list = g_list_copy (seat->priv->display_servers);
1877     for (link = list; link; link = link->next)
1878         g_object_ref (link->data);
1879     for (link = list; link; link = link->next)
1880     {
1881         DisplayServer *display_server = link->data;
1882         if (!display_server_get_is_stopping (display_server))
1883         {
1884             l_debug (seat, "Stopping display server");
1885             display_server_stop (display_server);
1886         }
1887     }
1888     g_list_free_full (list, g_object_unref);
1889     list = g_list_copy (seat->priv->sessions);
1890     for (link = list; link; link = link->next)
1891         g_object_ref (link->data);
1892     for (link = list; link; link = link->next)
1893     {
1894         Session *session = link->data;
1895         if (!session_get_is_stopping (session))
1896         {
1897             l_debug (seat, "Stopping session");
1898             session_stop (session);
1899         }
1900     }
1901     g_list_free_full (list, g_object_unref);
1902 }
1903
1904 static void
1905 seat_init (Seat *seat)
1906 {
1907     seat->priv = G_TYPE_INSTANCE_GET_PRIVATE (seat, SEAT_TYPE, SeatPrivate);
1908     seat->priv->properties = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, g_free);
1909     seat->priv->share_display_server = TRUE;
1910 }
1911
1912 static void
1913 seat_finalize (GObject *object)
1914 {
1915     Seat *self = SEAT (object);
1916     GList *link;
1917
1918     g_free (self->priv->name);
1919     g_hash_table_unref (self->priv->properties);
1920     for (link = self->priv->display_servers; link; link = link->next)
1921     {
1922         DisplayServer *display_server = link->data;
1923         g_signal_handlers_disconnect_matched (display_server, G_SIGNAL_MATCH_DATA, 0, 0, NULL, NULL, self);
1924     }
1925     g_list_free_full (self->priv->display_servers, g_object_unref);
1926     for (link = self->priv->sessions; link; link = link->next)
1927     {
1928         Session *session = link->data;
1929         g_signal_handlers_disconnect_matched (session, G_SIGNAL_MATCH_DATA, 0, 0, NULL, NULL, self);
1930     }
1931     g_list_free_full (self->priv->sessions, g_object_unref);
1932     g_clear_object (&self->priv->active_session);
1933     g_clear_object (&self->priv->next_session);
1934     g_clear_object (&self->priv->session_to_activate);
1935     g_clear_object (&self->priv->replacement_greeter);
1936
1937     G_OBJECT_CLASS (seat_parent_class)->finalize (object);
1938 }
1939
1940 static void
1941 seat_class_init (SeatClass *klass)
1942 {
1943     GObjectClass *object_class = G_OBJECT_CLASS (klass);
1944
1945     klass->setup = seat_real_setup;
1946     klass->start = seat_real_start;
1947     klass->create_greeter_session = seat_real_create_greeter_session;
1948     klass->create_session = seat_real_create_session;
1949     klass->set_active_session = seat_real_set_active_session;
1950     klass->get_active_session = seat_real_get_active_session;
1951     klass->set_next_session = seat_real_set_next_session;
1952     klass->run_script = seat_real_run_script;
1953     klass->stop = seat_real_stop;
1954
1955     object_class->finalize = seat_finalize;
1956
1957     g_type_class_add_private (klass, sizeof (SeatPrivate));
1958
1959     signals[SESSION_ADDED] =
1960         g_signal_new (SEAT_SIGNAL_SESSION_ADDED,
1961                       G_TYPE_FROM_CLASS (klass),
1962                       G_SIGNAL_RUN_LAST,
1963                       G_STRUCT_OFFSET (SeatClass, session_added),
1964                       NULL, NULL,
1965                       NULL,
1966                       G_TYPE_NONE, 1, SESSION_TYPE);
1967     signals[RUNNING_USER_SESSION] =
1968         g_signal_new (SEAT_SIGNAL_RUNNING_USER_SESSION,
1969                       G_TYPE_FROM_CLASS (klass),
1970                       G_SIGNAL_RUN_LAST,
1971                       G_STRUCT_OFFSET (SeatClass, running_user_session),
1972                       NULL, NULL,
1973                       NULL,
1974                       G_TYPE_NONE, 1, SESSION_TYPE);
1975     signals[SESSION_REMOVED] =
1976         g_signal_new (SEAT_SIGNAL_SESSION_REMOVED,
1977                       G_TYPE_FROM_CLASS (klass),
1978                       G_SIGNAL_RUN_LAST,
1979                       G_STRUCT_OFFSET (SeatClass, session_removed),
1980                       NULL, NULL,
1981                       NULL,
1982                       G_TYPE_NONE, 1, SESSION_TYPE);
1983     signals[STOPPED] =
1984         g_signal_new (SEAT_SIGNAL_STOPPED,
1985                       G_TYPE_FROM_CLASS (klass),
1986                       G_SIGNAL_RUN_LAST,
1987                       G_STRUCT_OFFSET (SeatClass, stopped),
1988                       NULL, NULL,
1989                       NULL,
1990                       G_TYPE_NONE, 0);
1991 }
1992
1993 static gint
1994 seat_real_logprefix (Logger *self, gchar *buf, gulong buflen)
1995 {
1996     return g_snprintf (buf, buflen, "Seat %s: ", SEAT (self)->priv->name);
1997 }
1998
1999 static void
2000 seat_logger_iface_init (LoggerInterface *iface)
2001 {
2002     iface->logprefix = &seat_real_logprefix;
2003 }