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