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