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     /* Configuration for this seat */
  34     GHashTable *properties;
  35
  36     /* TRUE if able to switch users */
  37     gboolean can_switch;
  38
  39     /* TRUE if display server can be shared for sessions */
  40     gboolean share_display_server;
  41
  42     /* The display servers on this seat */
  43     GList *display_servers;
  44
  45     /* The sessions on this seat */
  46     GList *sessions;
  47
  48     /* The last session set to active */
  49     Session *active_session;
  50
  51     /* The session belonging to the active greeter user */
  52     Session *next_session;
  53
  54     /* The session to set active when it starts */
  55     Session *session_to_activate;
  56
  57     /* TRUE once we have started */
  58     gboolean started;
  59
  60     /* TRUE if stopping this seat (waiting for displays to stop) */
  61     gboolean stopping;
  62
  63     /* TRUE if stopped */
  64     gboolean stopped;
  65 };
  66
  67 static void seat_logger_iface_init (LoggerInterface *iface);
  68
  69 G_DEFINE_TYPE_WITH_CODE (Seat, seat, G_TYPE_OBJECT,
  70                          G_IMPLEMENT_INTERFACE (
  71                              LOGGER_TYPE, seat_logger_iface_init));
  72
  73 typedef struct
  74 {
  75     const gchar *name;
  76     GType type;
  77 } SeatModule;
  78 static GHashTable *seat_modules = NULL;
  79
  80 // FIXME: Make a get_display_server() that re-uses display servers if supported
  81 static DisplayServer *create_display_server (Seat *seat, const gchar *session_type);
  82 static Greeter *create_greeter_session (Seat *seat);
  83 static void start_session (Seat *seat, Session *session);
  84
  85 void
  86 seat_register_module (const gchar *name, GType type)
  87 {
  88     SeatModule *module;
  89
  90     if (!seat_modules)
  91         seat_modules = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, NULL);
  92
  93     g_debug ("Registered seat module %s", name);
  94
  95     module = g_malloc0 (sizeof (SeatModule));
  96     module->name = g_strdup (name);
  97     module->type = type;
  98     g_hash_table_insert (seat_modules, g_strdup (name), module);
  99 }
 100
 101 Seat *
 102 seat_new (const gchar *module_name)
 103 {
 104     Seat *seat;
 105     SeatModule *m = NULL;
 106
 107     g_return_val_if_fail (module_name != NULL, NULL);
 108
 109     if (seat_modules)
 110         m = g_hash_table_lookup (seat_modules, module_name);
 111     if (!m)
 112         return NULL;
 113
 114     seat = g_object_new (m->type, NULL);
 115
 116     return seat;
 117 }
 118
 119 void
 120 seat_set_property (Seat *seat, const gchar *name, const gchar *value)
 121 {
 122     g_return_if_fail (seat != NULL);
 123     g_hash_table_insert (seat->priv->properties, g_strdup (name), g_strdup (value));
 124 }
 125
 126 const gchar *
 127 seat_get_string_property (Seat *seat, const gchar *name)
 128 {
 129     g_return_val_if_fail (seat != NULL, NULL);
 130     return g_hash_table_lookup (seat->priv->properties, name);
 131 }
 132
 133 gchar **
 134 seat_get_string_list_property (Seat *seat, const gchar *name)
 135 {
 136     g_return_val_if_fail (seat != NULL, NULL);
 137     return g_strsplit (g_hash_table_lookup (seat->priv->properties, name), ";", 0);
 138 }
 139
 140 gboolean
 141 seat_get_boolean_property (Seat *seat, const gchar *name)
 142 {
 143     return g_strcmp0 (seat_get_string_property (seat, name), "true") == 0;
 144 }
 145
 146 gint
 147 seat_get_integer_property (Seat *seat, const gchar *name)
 148 {
 149     const gchar *value;
 150
 151     value = seat_get_string_property (seat, name);
 152     return value ? atoi (value) : 0;
 153 }
 154
 155 const gchar *
 156 seat_get_name (Seat *seat)
 157 {
 158     const gchar *name;
 159
 160     name = seat_get_string_property (seat, "xdg-seat");
 161     if (name)
 162         return name;
 163
 164     return "seat0";
 165 }
 166
 167 void
 168 seat_set_can_switch (Seat *seat, gboolean can_switch)
 169 {
 170     g_return_if_fail (seat != NULL);
 171
 172     seat->priv->can_switch = can_switch;
 173 }
 174
 175 void
 176 seat_set_share_display_server (Seat *seat, gboolean share_display_server)
 177 {
 178     g_return_if_fail (seat != NULL);
 179
 180     seat->priv->share_display_server = share_display_server;
 181 }
 182
 183 gboolean
 184 seat_start (Seat *seat)
 185 {
 186     g_return_val_if_fail (seat != NULL, FALSE);
 187
 188     SEAT_GET_CLASS (seat)->setup (seat);
 189     return SEAT_GET_CLASS (seat)->start (seat);
 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->priv->can_switch;
 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 gboolean
 373 get_start_local_sessions (Seat *seat)
 374 {
 375     return SEAT_GET_CLASS (seat)->get_start_local_sessions (seat);
 376 }
 377
 378 static void
 379 display_server_stopped_cb (DisplayServer *display_server, Seat *seat)
 380 {
 381     const gchar *script;
 382     GList *list, *link;
 383     Session *active_session;
 384
 385     l_debug (seat, "Display server stopped");
 386
 387     /* Run a script right after stopping the display server */
 388     script = seat_get_string_property (seat, "display-stopped-script");
 389     if (script)
 390         run_script (seat, NULL, script, NULL);
 391
 392     g_signal_handlers_disconnect_matched (display_server, G_SIGNAL_MATCH_DATA, 0, 0, NULL, NULL, seat);
 393     seat->priv->display_servers = g_list_remove (seat->priv->display_servers, display_server);
 394
 395     if (seat->priv->stopping || !seat->priv->started)
 396     {
 397         check_stopped (seat);
 398         g_object_unref (display_server);
 399         return;
 400     }
 401
 402     /* Stop all sessions on this display server */
 403     list = g_list_copy (seat->priv->sessions);
 404     for (link = list; link; link = link->next)
 405         g_object_ref (link->data);
 406     for (link = list; link; link = link->next)
 407     {
 408         Session *session = link->data;
 409
 410         if (session_get_display_server (session) != display_server || session_get_is_stopping (session))
 411             continue;
 412
 413         /* Stop seat if this is the only display server and it failed to start a greeter */
 414         if (IS_GREETER (session) &&
 415             !session_get_is_started (session) &&
 416             g_list_length (seat->priv->display_servers) == 0)
 417         {
 418             l_debug (seat, "Stopping; greeter display server failed to start");
 419             seat_stop (seat);
 420         }
 421
 422         l_debug (seat, "Stopping session");
 423         session_stop (session);
 424     }
 425     g_list_free_full (list, g_object_unref);
 426
 427     if (!seat->priv->stopping && get_start_local_sessions (seat))
 428     {
 429         /* If we were the active session, switch to a greeter */
 430         active_session = seat_get_active_session (seat);
 431         if (!active_session || session_get_display_server (active_session) == display_server)
 432         {
 433             l_debug (seat, "Active display server stopped, starting greeter");
 434             if (!seat_switch_to_greeter (seat))
 435             {
 436                 l_debug (seat, "Stopping; failed to start a greeter");
 437                 seat_stop (seat);
 438             }
 439         }
 440     }
 441
 442     g_object_unref (display_server);
 443 }
 444
 445 static gboolean
 446 can_share_display_server (Seat *seat, DisplayServer *display_server)
 447 {
 448     return seat->priv->share_display_server && display_server_get_can_share (display_server);
 449 }
 450
 451 static Greeter *
 452 find_greeter_session (Seat *seat)
 453 {
 454     GList *link;
 455
 456     for (link = seat->priv->sessions; link; link = link->next)
 457     {
 458         Session *session = link->data;
 459         if (!session_get_is_stopping (session) && IS_GREETER (session))
 460             return GREETER (session);
 461     }
 462
 463     return NULL;
 464 }
 465
 466 static Greeter *
 467 find_resettable_greeter (Seat *seat)
 468 {
 469     GList *link;
 470
 471     for (link = seat->priv->sessions; link; link = link->next)
 472     {
 473         Session *session = link->data;
 474         if (!session_get_is_stopping (session) && IS_GREETER (session) &&
 475             greeter_get_resettable (GREETER (session)))
 476             return GREETER (session);
 477     }
 478
 479     return NULL;
 480 }
 481
 482 static void
 483 set_greeter_hints (Seat *seat, Greeter *greeter_session)
 484 {
 485     greeter_clear_hints (greeter_session);
 486     greeter_set_hint (greeter_session, "default-session", seat_get_string_property (seat, "user-session"));
 487     greeter_set_hint (greeter_session, "hide-users", seat_get_boolean_property (seat, "greeter-hide-users") ? "true" : "false");
 488     greeter_set_hint (greeter_session, "show-manual-login", seat_get_boolean_property (seat, "greeter-show-manual-login") ? "true" : "false");
 489     greeter_set_hint (greeter_session, "show-remote-login", seat_get_boolean_property (seat, "greeter-show-remote-login") ? "true" : "false");
 490     greeter_set_hint (greeter_session, "has-guest-account", seat_get_allow_guest (seat) && seat_get_boolean_property (seat, "greeter-allow-guest") ? "true" : "false");
 491 }
 492
 493 static void
 494 switch_to_greeter_from_failed_session (Seat *seat, Session *session)
 495 {
 496     Greeter *greeter_session;
 497     gboolean existing = FALSE;
 498
 499     /* Switch to greeter if one open */
 500     greeter_session = find_resettable_greeter (seat);
 501     if (greeter_session)
 502     {
 503         l_debug (seat, "Switching to existing greeter");
 504         set_greeter_hints (seat, greeter_session);
 505         existing = TRUE;
 506     }
 507     else
 508     {
 509         greeter_session = create_greeter_session (seat);
 510     }
 511
 512     if (session_get_is_guest (session))
 513         greeter_set_hint (greeter_session, "select-guest", "true");
 514     else
 515         greeter_set_hint (greeter_session, "select-user", session_get_username (session));
 516
 517     if (existing)
 518     {
 519         greeter_reset (greeter_session);
 520         seat_set_active_session (seat, SESSION (greeter_session));
 521     }
 522     else
 523     {
 524         if (seat->priv->session_to_activate)
 525             g_object_unref (seat->priv->session_to_activate);
 526         seat->priv->session_to_activate = g_object_ref (greeter_session);
 527
 528         if (can_share_display_server (seat, session_get_display_server (session)))
 529             session_set_display_server (SESSION (greeter_session), session_get_display_server (session));
 530         else
 531         {
 532             DisplayServer *display_server;
 533
 534             display_server = create_display_server (seat, session_get_session_type (session));
 535             session_set_display_server (session, display_server);
 536             if (!display_server_start (display_server))
 537             {
 538                 l_debug (seat, "Failed to start display server for greeter");
 539                 seat_stop (seat);
 540             }
 541         }
 542
 543         start_session (seat, SESSION (greeter_session));
 544     }
 545
 546     /* Stop failed session */
 547     session_stop (session);
 548 }
 549
 550 static void
 551 start_session (Seat *seat, Session *session)
 552 {
 553     /* Use system location for greeter log file */
 554     if (IS_GREETER (session))
 555     {
 556         gchar *log_dir, *filename, *log_filename;
 557
 558         log_dir = config_get_string (config_get_instance (), "LightDM", "log-directory");
 559         filename = g_strdup_printf ("%s-greeter.log", display_server_get_name (session_get_display_server (session)));
 560         log_filename = g_build_filename (log_dir, filename, NULL);
 561         g_free (log_dir);
 562         g_free (filename);
 563         session_set_log_file (session, log_filename);
 564         g_free (log_filename);
 565     }
 566
 567     if (session_start (session))
 568         return;
 569
 570     if (IS_GREETER (session))
 571     {
 572         l_debug (seat, "Failed to start greeter");
 573         display_server_stop (session_get_display_server (session));
 574         return;
 575     }
 576
 577     l_debug (seat, "Failed to start session, starting greeter");
 578     switch_to_greeter_from_failed_session (seat, session);
 579 }
 580
 581 static void
 582 run_session (Seat *seat, Session *session)
 583 {
 584     const gchar *script;
 585
 586     if (IS_GREETER (session))
 587         script = seat_get_string_property (seat, "greeter-setup-script");
 588     else
 589         script = seat_get_string_property (seat, "session-setup-script");
 590     if (script && !run_script (seat, session_get_display_server (session), script, session_get_user (session)))
 591     {
 592         l_debug (seat, "Switching to greeter due to failed setup script");
 593         switch_to_greeter_from_failed_session (seat, session);
 594         return;
 595     }
 596
 597     if (!IS_GREETER (session))
 598     {
 599         g_signal_emit (seat, signals[RUNNING_USER_SESSION], 0, session);
 600         emit_upstart_signal ("desktop-session-start");
 601     }
 602
 603     session_run (session);
 604
 605     // FIXME: Wait until the session is ready
 606
 607     if (session == seat->priv->session_to_activate)
 608     {
 609         seat_set_active_session (seat, session);
 610         g_object_unref (seat->priv->session_to_activate);
 611         seat->priv->session_to_activate = NULL;
 612     }
 613     else if (seat->priv->active_session)
 614     {
 615         /* Multiple sessions can theoretically be on the same VT (especially
 616            if using Mir).  If a new session appears on an existing active VT,
 617            logind will mark it as active, while ConsoleKit will re-mark the
 618            oldest session as active.  In either case, that may not be the
 619            session that we want to be active.  So let's be explicit and
 620            re-activate the correct session whenever a new session starts.
 621            There's no harm to do this in seats that enforce separate VTs. */
 622         session_activate (seat->priv->active_session);
 623     }
 624 }
 625
 626 static Session *
 627 find_user_session (Seat *seat, const gchar *username, Session *ignore_session)
 628 {
 629     GList *link;
 630
 631     if (!username)
 632         return NULL;
 633
 634     for (link = seat->priv->sessions; link; link = link->next)
 635     {
 636         Session *session = link->data;
 637
 638         if (session == ignore_session)
 639             continue;
 640
 641         if (!session_get_is_stopping (session) && g_strcmp0 (session_get_username (session), username) == 0)
 642             return session;
 643     }
 644
 645     return NULL;
 646 }
 647
 648 static void
 649 greeter_active_username_changed_cb (Greeter *greeter, GParamSpec *pspec, Seat *seat)
 650 {
 651     Session *session;
 652
 653     session = find_user_session (seat, greeter_get_active_username (greeter), seat->priv->active_session);
 654
 655     if (seat->priv->next_session)
 656         g_object_unref (seat->priv->next_session);
 657     seat->priv->next_session = session ? g_object_ref (session) : NULL;
 658
 659     SEAT_GET_CLASS (seat)->set_next_session (seat, session);
 660 }
 661
 662 static void
 663 session_authentication_complete_cb (Session *session, Seat *seat)
 664 {
 665     if (session_get_is_authenticated (session))
 666     {
 667         Session *s;
 668
 669         s = find_user_session (seat, session_get_username (session), session);
 670         if (s)
 671         {
 672             l_debug (seat, "Session authenticated, switching to existing user session");
 673             seat_set_active_session (seat, s);
 674             session_stop (session);
 675         }
 676         else
 677         {
 678             l_debug (seat, "Session authenticated, running command");
 679             run_session (seat, session);
 680         }
 681     }
 682     else if (!IS_GREETER (session))
 683     {
 684         l_debug (seat, "Switching to greeter due to failed authentication");
 685         switch_to_greeter_from_failed_session (seat, session);
 686     }
 687     else
 688     {
 689         l_debug (seat, "Stopping session that failed authentication");
 690         session_stop (session);
 691     }
 692 }
 693
 694 static void
 695 session_stopped_cb (Session *session, Seat *seat)
 696 {
 697     DisplayServer *display_server;
 698
 699     l_debug (seat, "Session stopped");
 700
 701     g_signal_handlers_disconnect_matched (session, G_SIGNAL_MATCH_DATA, 0, 0, NULL, NULL, seat);
 702     seat->priv->sessions = g_list_remove (seat->priv->sessions, session);
 703     if (session == seat->priv->active_session)
 704     {
 705         g_object_unref (seat->priv->active_session);
 706         seat->priv->active_session = NULL;
 707     }
 708     if (session == seat->priv->next_session)
 709     {
 710         g_object_unref (seat->priv->next_session);
 711         seat->priv->next_session = NULL;
 712     }
 713     if (session == seat->priv->session_to_activate)
 714     {
 715         g_object_unref (seat->priv->session_to_activate);
 716         seat->priv->session_to_activate = NULL;
 717     }
 718
 719     display_server = session_get_display_server (session);
 720     if (!display_server)
 721     {
 722         g_object_unref (session);
 723         return;
 724     }
 725
 726     /* Cleanup */
 727     if (!IS_GREETER (session))
 728     {
 729         const gchar *script;
 730         script = seat_get_string_property (seat, "session-cleanup-script");
 731         if (script)
 732             run_script (seat, display_server, script, session_get_user (session));
 733     }
 734
 735     /* We were waiting for this session, but it didn't start :( */
 736     // FIXME: Start a greeter on this?
 737     if (session == seat->priv->session_to_activate)
 738     {
 739         g_object_unref (seat->priv->session_to_activate);
 740         seat->priv->session_to_activate = NULL;
 741     }
 742
 743     if (seat->priv->stopping)
 744     {
 745         check_stopped (seat);
 746         g_object_unref (session);
 747         return;
 748     }
 749
 750     /* If this is the greeter session then re-use this display server */
 751     if (IS_GREETER (session) &&
 752         can_share_display_server (seat, display_server) &&
 753         greeter_get_start_session (GREETER (session)))
 754     {
 755         GList *link;
 756
 757         for (link = seat->priv->sessions; link; link = link->next)
 758         {
 759             Session *s = link->data;
 760
 761             /* Skip this session and sessions on other display servers */
 762             if (s == session || session_get_display_server (s) != display_server || session_get_is_stopping (s))
 763                 continue;
 764
 765             if (session_get_is_authenticated (s))
 766             {
 767                 l_debug (seat, "Greeter stopped, running session");
 768                 run_session (seat, s);
 769             }
 770             else
 771             {
 772                 l_debug (seat, "Greeter stopped, starting session authentication");
 773                 start_session (seat, s);
 774             }
 775             break;
 776         }
 777     }
 778     /* If this is the greeter and nothing else is running then stop the seat */
 779     else if (IS_GREETER (session) &&
 780         !greeter_get_start_session (GREETER (session)) &&
 781         g_list_length (seat->priv->display_servers) == 1 &&
 782         g_list_nth_data (seat->priv->display_servers, 0) == display_server)
 783     {
 784         l_debug (seat, "Stopping; failed to start a greeter");
 785         seat_stop (seat);
 786     }
 787     /* If we were the active session, switch to a greeter */
 788     else if (!IS_GREETER (session) && session == seat_get_active_session (seat))
 789     {
 790         l_debug (seat, "Active session stopped, starting greeter");
 791         if (!seat_switch_to_greeter (seat))
 792         {
 793             l_debug (seat, "Stopping; failed to start a greeter");
 794             seat_stop (seat);
 795         }
 796     }
 797
 798     /* Stop the display server if no-longer required */
 799     if (display_server && !display_server_get_is_stopping (display_server))
 800     {
 801         GList *link;
 802         int n_sessions = 0;
 803
 804         for (link = seat->priv->sessions; link; link = link->next)
 805         {
 806             Session *s = link->data;
 807             if (s == session)
 808                 continue;
 809             if (session_get_display_server (s) == display_server)
 810                 n_sessions++;
 811         }
 812         if (n_sessions == 0)
 813         {
 814             l_debug (seat, "Stopping display server, no sessions require it");
 815             display_server_stop (display_server);
 816         }
 817     }
 818
 819     g_signal_emit (seat, signals[SESSION_REMOVED], 0, session);
 820     g_object_unref (session);
 821 }
 822
 823 static void
 824 set_session_env (Session *session)
 825 {
 826     /* Connect using the session bus */
 827     if (getuid () != 0)
 828     {
 829         if (g_getenv ("DBUS_SESSION_BUS_ADDRESS"))
 830             session_set_env (session, "DBUS_SESSION_BUS_ADDRESS", g_getenv ("DBUS_SESSION_BUS_ADDRESS"));
 831         session_set_env (session, "LDM_BUS", "SESSION");
 832         if (g_getenv ("LD_PRELOAD"))
 833             session_set_env (session, "LD_PRELOAD", g_getenv ("LD_PRELOAD"));
 834         if (g_getenv ("LD_LIBRARY_PATH"))
 835             session_set_env (session, "LD_LIBRARY_PATH", g_getenv ("LD_LIBRARY_PATH"));
 836         if (g_getenv ("PATH"))
 837             session_set_env (session, "PATH", g_getenv ("PATH"));
 838     }
 839
 840     /* Variables required for regression tests */
 841     if (g_getenv ("LIGHTDM_TEST_ROOT"))
 842     {
 843         session_set_env (session, "LIGHTDM_TEST_ROOT", g_getenv ("LIGHTDM_TEST_ROOT"));
 844         session_set_env (session, "DBUS_SYSTEM_BUS_ADDRESS", g_getenv ("DBUS_SYSTEM_BUS_ADDRESS"));
 845         session_set_env (session, "DBUS_SESSION_BUS_ADDRESS", g_getenv ("DBUS_SESSION_BUS_ADDRESS"));
 846         session_set_env (session, "LD_PRELOAD", g_getenv ("LD_PRELOAD"));
 847         session_set_env (session, "LD_LIBRARY_PATH", g_getenv ("LD_LIBRARY_PATH"));
 848         session_set_env (session, "GI_TYPELIB_PATH", g_getenv ("GI_TYPELIB_PATH"));
 849     }
 850 }
 851
 852 static Session *
 853 create_session (Seat *seat, gboolean autostart)
 854 {
 855     Session *session;
 856
 857     session = SEAT_GET_CLASS (seat)->create_session (seat);
 858     seat->priv->sessions = g_list_append (seat->priv->sessions, session);
 859     if (autostart)
 860         g_signal_connect (session, "authentication-complete", G_CALLBACK (session_authentication_complete_cb), seat);
 861     g_signal_connect (session, "stopped", G_CALLBACK (session_stopped_cb), seat);
 862
 863     set_session_env (session);
 864
 865     g_signal_emit (seat, signals[SESSION_ADDED], 0, session);
 866
 867     return session;
 868 }
 869
 870 static gchar **
 871 get_session_argv (Seat *seat, SessionConfig *session_config, const gchar *session_wrapper)
 872 {
 873     gboolean result;
 874     int argc;
 875     gchar **argv, *path;
 876     GError *error = NULL;
 877
 878     /* If configured, run sessions through a wrapper */
 879     if (session_wrapper)
 880     {
 881         argv = g_malloc (sizeof (gchar *) * 3);
 882         path = g_find_program_in_path (session_wrapper);
 883         argv[0] = path ? path : g_strdup (session_wrapper);
 884         argv[1] = g_strdup (session_config_get_command (session_config));
 885         argv[2] = NULL;
 886         return argv;
 887     }
 888
 889     /* Split command into an array listing and make command absolute */
 890     result = g_shell_parse_argv (session_config_get_command (session_config), &argc, &argv, &error);
 891     if (error)
 892         l_debug (seat, "Invalid session command '%s': %s", session_config_get_command (session_config), error->message);
 893     g_clear_error (&error);
 894     if (!result)
 895         return NULL;
 896     path = g_find_program_in_path (argv[0]);
 897     if (path)
 898     {
 899         g_free (argv[0]);
 900         argv[0] = path;
 901     }
 902
 903     return argv;
 904 }
 905
 906 static SessionConfig *
 907 find_session_config (Seat *seat, const gchar *sessions_dir, const gchar *session_name)
 908 {
 909     gchar **dirs;
 910     SessionConfig *session_config = NULL;
 911     int i;
 912     GError *error = NULL;
 913
 914     g_return_val_if_fail (sessions_dir != NULL, NULL);
 915     g_return_val_if_fail (session_name != NULL, NULL);
 916
 917     dirs = g_strsplit (sessions_dir, ":", -1);
 918     for (i = 0; dirs[i]; i++)
 919     {
 920         gchar *filename, *path;
 921
 922         filename = g_strdup_printf ("%s.desktop", session_name);
 923         path = g_build_filename (dirs[i], filename, NULL);
 924         g_free (filename);
 925         session_config = session_config_new_from_file (path, &error);
 926         g_free (path);
 927         if (session_config)
 928             break;
 929
 930         if (dirs[i+1] == NULL)
 931             l_debug (seat, "Failed to find session configuration %s", session_name);
 932         g_clear_error (&error);
 933     }
 934     g_strfreev (dirs);
 935
 936     return session_config;
 937 }
 938
 939 static void
 940 configure_session (Session *session, SessionConfig *config, const gchar *session_name, const gchar *language)
 941 {
 942     const gchar *desktop_name;
 943
 944     session_set_session_type (session, session_config_get_session_type (config));
 945     session_set_env (session, "XDG_SESSION_DESKTOP", session_name);
 946     session_set_env (session, "DESKTOP_SESSION", session_name);
 947     session_set_env (session, "GDMSESSION", session_name);
 948     desktop_name = session_config_get_desktop_name (config);
 949     if (desktop_name)
 950         session_set_env (session, "XDG_CURRENT_DESKTOP", desktop_name);
 951     if (language && language[0] != '\0')
 952     {
 953         session_set_env (session, "LANG", language);
 954         session_set_env (session, "GDM_LANG", language);
 955     }
 956 }
 957
 958 static Session *
 959 create_user_session (Seat *seat, const gchar *username, gboolean autostart)
 960 {
 961     User *user;
 962     gchar *sessions_dir;
 963     const gchar *session_name, *language;
 964     SessionConfig *session_config;
 965     Session *session = NULL;
 966
 967     l_debug (seat, "Creating user session");
 968
 969     /* Load user preferences */
 970     user = accounts_get_user_by_name (username);
 971     if (!user)
 972     {
 973         l_debug (seat, "Can't login unknown user '%s'", username);
 974         return NULL;
 975     }
 976     session_name = user_get_xsession (user);
 977     language = user_get_language (user);
 978
 979     if (!session_name)
 980         session_name = seat_get_string_property (seat, "user-session");
 981     sessions_dir = config_get_string (config_get_instance (), "LightDM", "sessions-directory");
 982     session_config = find_session_config (seat, sessions_dir, session_name);
 983     g_free (sessions_dir);
 984     if (session_config)
 985     {
 986         gchar **argv;
 987
 988         session = create_session (seat, autostart);
 989         configure_session (session, session_config, session_name, language);
 990         session_set_username (session, username);
 991         session_set_do_authenticate (session, TRUE);
 992         argv = get_session_argv (seat, session_config, seat_get_string_property (seat, "session-wrapper"));
 993         session_set_argv (session, argv);
 994         g_strfreev (argv);
 995         g_object_unref (session_config);
 996     }
 997     else
 998         l_debug (seat, "Can't find session '%s'", session_name);
 999
1000     g_object_unref (user);
1001
1002     return session;
1003 }
1004
1005 static void
1006 prepend_argv (gchar ***argv, const gchar *value)
1007 {
1008     gchar **old_argv, **new_argv;
1009     gint i;
1010
1011     old_argv = *argv;
1012     new_argv = g_malloc (sizeof (gchar *) * (g_strv_length (*argv) + 2));
1013     new_argv[0] = g_strdup (value);
1014     for (i = 0; old_argv[i]; i++)
1015         new_argv[i + 1] = old_argv[i];
1016     new_argv[i + 1] = NULL;
1017
1018     g_free (*argv);
1019     *argv = new_argv;
1020 }
1021
1022 static Session *
1023 create_guest_session (Seat *seat, const gchar *session_name)
1024 {
1025     const gchar *guest_wrapper;
1026     gchar *sessions_dir, **argv;
1027     SessionConfig *session_config;
1028     Session *session;
1029
1030     if (!session_name)
1031         session_name = seat_get_string_property (seat, "guest-session");
1032     if (!session_name)
1033         session_name = seat_get_string_property (seat, "user-session");
1034     sessions_dir = config_get_string (config_get_instance (), "LightDM", "sessions-directory");
1035     session_config = find_session_config (seat, sessions_dir, session_name);
1036     g_free (sessions_dir);
1037     if (!session_config)
1038     {
1039         l_debug (seat, "Can't find session '%s'", session_name);
1040         return NULL;
1041     }
1042
1043     session = create_session (seat, TRUE);
1044     configure_session (session, session_config, session_name, NULL);
1045     session_set_do_authenticate (session, TRUE);
1046     session_set_is_guest (session, TRUE);
1047     argv = get_session_argv (seat, session_config, seat_get_string_property (seat, "session-wrapper"));
1048     guest_wrapper = seat_get_string_property (seat, "guest-wrapper");
1049     if (guest_wrapper)
1050     {
1051         gchar *path;
1052         path = g_find_program_in_path (guest_wrapper);
1053         prepend_argv (&argv, path ? path : guest_wrapper);
1054         g_free (path);
1055     }
1056
1057     session_set_argv (session, argv);
1058     g_strfreev (argv);
1059     g_object_unref (session_config);
1060
1061     return session;
1062 }
1063
1064 static Session *
1065 greeter_create_session_cb (Greeter *greeter, Seat *seat)
1066 {
1067     Session *session;
1068
1069     session = create_session (seat, FALSE);
1070     session_set_session_type (session, session_get_session_type (SESSION (greeter)));
1071     session_set_display_server (session, session_get_display_server (SESSION (greeter)));
1072
1073     return g_object_ref (session);
1074 }
1075
1076 static gboolean
1077 greeter_start_session_cb (Greeter *greeter, SessionType type, const gchar *session_name, Seat *seat)
1078 {
1079     Session *session, *existing_session;
1080     const gchar *username;
1081     DisplayServer *display_server;
1082
1083     /* Get the session to use */
1084     if (greeter_get_guest_authenticated (greeter))
1085     {
1086         session = create_guest_session (seat, session_name);
1087         if (!session)
1088             return FALSE;
1089         session_set_pam_service (session, seat_get_string_property (seat, "pam-autologin-service"));
1090     }
1091     else
1092     {
1093         const gchar *language = NULL;
1094         SessionConfig *session_config;
1095         User *user;
1096         gchar *sessions_dir = NULL;
1097         gchar **argv;
1098
1099         session = greeter_get_authentication_session (greeter);
1100
1101         /* Get session command to run */
1102         switch (type)
1103         {
1104         case SESSION_TYPE_LOCAL:
1105             sessions_dir = config_get_string (config_get_instance (), "LightDM", "sessions-directory");
1106             break;
1107         case SESSION_TYPE_REMOTE:
1108             sessions_dir = config_get_string (config_get_instance (), "LightDM", "remote-sessions-directory");
1109             break;
1110         }
1111
1112         /* Load user preferences */
1113         user = session_get_user (session);
1114         if (user)
1115         {
1116             if (!session_name)
1117                 session_name = user_get_xsession (user);
1118             language = user_get_language (user);
1119         }
1120
1121         if (!session_name)
1122             session_name = seat_get_string_property (seat, "user-session");
1123         if (user)
1124             user_set_xsession (session_get_user (session), session_name);
1125
1126         session_config = find_session_config (seat, sessions_dir, session_name);
1127         g_free (sessions_dir);
1128         if (!session_config)
1129         {
1130             l_debug (seat, "Can't find session '%s'", session_name);
1131             return FALSE;
1132         }
1133
1134         configure_session (session, session_config, session_name, language);
1135         argv = get_session_argv (seat, session_config, seat_get_string_property (seat, "session-wrapper"));
1136         session_set_argv (session, argv);
1137         g_strfreev (argv);
1138         g_object_unref (session_config);
1139     }
1140
1141     /* Switch to this session when it is ready */
1142     if (seat->priv->session_to_activate)
1143         g_object_unref (seat->priv->session_to_activate);
1144     seat->priv->session_to_activate = g_object_ref (session);
1145
1146     /* Return to existing session if it is open */
1147     username = session_get_username (session);
1148     existing_session = find_user_session (seat, username, NULL);
1149     if (existing_session && session != existing_session)
1150     {
1151         l_debug (seat, "Returning to existing user session %s", username);
1152         session_stop (session);
1153         session_unlock (existing_session);
1154         seat_set_active_session (seat, existing_session);
1155         return TRUE;
1156     }
1157
1158     /* If can re-use the display server, stop the greeter first */
1159     display_server = session_get_display_server (SESSION (greeter));
1160     if (!greeter_get_resettable (greeter) &&
1161         can_share_display_server (seat, display_server) &&
1162         strcmp (display_server_get_session_type (display_server), session_get_session_type (session)) == 0)
1163     {
1164         l_debug (seat, "Stopping greeter; display server will be re-used for user session");
1165
1166         /* Run on the same display server after the greeter has stopped */
1167         session_set_display_server (session, display_server);
1168
1169         /* Stop the greeter */
1170         session_stop (SESSION (greeter));
1171
1172         return TRUE;
1173     }
1174     /* Otherwise start a new display server for this session */
1175     else
1176     {
1177         display_server = create_display_server (seat, session_get_session_type (session));
1178         session_set_display_server (session, display_server);
1179         if (!display_server_start (display_server))
1180         {
1181             l_debug (seat, "Failed to start display server for new session");
1182             return FALSE;
1183         }
1184
1185         return TRUE;
1186     }
1187 }
1188
1189 static Greeter *
1190 create_greeter_session (Seat *seat)
1191 {
1192     gchar *sessions_dir, **argv;
1193     SessionConfig *session_config;
1194     Greeter *greeter_session;
1195     const gchar *greeter_wrapper;
1196     const gchar *autologin_username;
1197     int autologin_timeout;
1198     gboolean autologin_guest;
1199
1200     l_debug (seat, "Creating greeter session");
1201
1202     sessions_dir = config_get_string (config_get_instance (), "LightDM", "greeters-directory");
1203     session_config = find_session_config (seat, sessions_dir, seat_get_string_property (seat, "greeter-session"));
1204     g_free (sessions_dir);
1205     if (!session_config)
1206         return NULL;
1207
1208     argv = get_session_argv (seat, session_config, NULL);
1209     greeter_wrapper = seat_get_string_property (seat, "greeter-wrapper");
1210     if (greeter_wrapper)
1211     {
1212         gchar *path;
1213         path = g_find_program_in_path (greeter_wrapper);
1214         prepend_argv (&argv, path ? path : greeter_wrapper);
1215         g_free (path);
1216     }
1217
1218     greeter_session = SEAT_GET_CLASS (seat)->create_greeter_session (seat);
1219     session_set_session_type (SESSION (greeter_session), session_config_get_session_type (session_config));
1220     seat->priv->sessions = g_list_append (seat->priv->sessions, SESSION (greeter_session));
1221     g_signal_connect (greeter_session, "notify::active-username", G_CALLBACK (greeter_active_username_changed_cb), seat);
1222     g_signal_connect (greeter_session, "authentication-complete", G_CALLBACK (session_authentication_complete_cb), seat);
1223     g_signal_connect (greeter_session, "stopped", G_CALLBACK (session_stopped_cb), seat);
1224
1225     set_session_env (SESSION (greeter_session));
1226     session_set_env (SESSION (greeter_session), "XDG_SESSION_CLASS", "greeter");
1227
1228     session_set_pam_service (SESSION (greeter_session), seat_get_string_property (seat, "pam-greeter-service"));
1229     if (getuid () == 0)
1230     {
1231         gchar *greeter_user;
1232         greeter_user = config_get_string (config_get_instance (), "LightDM", "greeter-user");
1233         session_set_username (SESSION (greeter_session), greeter_user);
1234         g_free (greeter_user);
1235     }
1236     else
1237     {
1238         /* In test mode run the greeter as ourself */
1239         session_set_username (SESSION (greeter_session), user_get_name (accounts_get_current_user ()));
1240     }
1241     session_set_argv (SESSION (greeter_session), argv);
1242     g_strfreev (argv);
1243
1244     greeter_set_pam_services (greeter_session,
1245                               seat_get_string_property (seat, "pam-service"),
1246                               seat_get_string_property (seat, "pam-autologin-service"));
1247     g_signal_connect (greeter_session, "create-session", G_CALLBACK (greeter_create_session_cb), seat);
1248     g_signal_connect (greeter_session, "start-session", G_CALLBACK (greeter_start_session_cb), seat);
1249
1250     /* Set hints to greeter */
1251     greeter_set_allow_guest (greeter_session, seat_get_allow_guest (seat));
1252     set_greeter_hints (seat, greeter_session);
1253
1254     /* Configure for automatic login */
1255     autologin_username = seat_get_string_property (seat, "autologin-user");
1256     if (g_strcmp0 (autologin_username, "") == 0)
1257         autologin_username = NULL;
1258     autologin_timeout = seat_get_integer_property (seat, "autologin-user-timeout");
1259     autologin_guest = seat_get_boolean_property (seat, "autologin-guest");
1260     if (autologin_timeout > 0)
1261     {
1262         gchar *value;
1263
1264         value = g_strdup_printf ("%d", autologin_timeout);
1265         greeter_set_hint (greeter_session, "autologin-timeout", value);
1266         g_free (value);
1267         if (autologin_username)
1268             greeter_set_hint (greeter_session, "autologin-user", autologin_username);
1269         if (autologin_guest)
1270             greeter_set_hint (greeter_session, "autologin-guest", "true");
1271     }
1272
1273     g_object_unref (session_config);
1274
1275     return greeter_session;
1276 }
1277
1278 static Session *
1279 find_session_for_display_server (Seat *seat, DisplayServer *display_server)
1280 {
1281     GList *link;
1282
1283     for (link = seat->priv->sessions; link; link = link->next)
1284     {
1285         Session *session = link->data;
1286         if (session_get_display_server (session) == display_server && !session_get_is_stopping (session))
1287             return session;
1288     }
1289
1290     return NULL;
1291 }
1292
1293 static void
1294 display_server_ready_cb (DisplayServer *display_server, Seat *seat)
1295 {
1296     const gchar *script;
1297     Session *session;
1298
1299     /* Run setup script */
1300     script = seat_get_string_property (seat, "display-setup-script");
1301     if (script && !run_script (seat, display_server, script, NULL))
1302     {
1303         l_debug (seat, "Stopping display server due to failed setup script");
1304         display_server_stop (display_server);
1305         return;
1306     }
1307
1308     /* Stop if don't need to run a session */
1309     if (!get_start_local_sessions (seat))
1310         return;
1311
1312     emit_upstart_signal ("login-session-start");
1313
1314     /* Start the session waiting for this display server */
1315     session = find_session_for_display_server (seat, display_server);
1316     if (session)
1317     {
1318         if (session_get_is_authenticated (session))
1319         {
1320             l_debug (seat, "Display server ready, running session");
1321             run_session (seat, session);
1322         }
1323         else
1324         {
1325             l_debug (seat, "Display server ready, starting session authentication");
1326             start_session (seat, session);
1327         }
1328     }
1329     else
1330     {
1331         l_debug (seat, "Stopping not required display server");
1332         display_server_stop (display_server);
1333     }
1334 }
1335
1336 static DisplayServer *
1337 create_display_server (Seat *seat, const gchar *session_type)
1338 {
1339     DisplayServer *display_server;
1340
1341     l_debug (seat, "Creating display server of type %s", session_type);
1342
1343     display_server = SEAT_GET_CLASS (seat)->create_display_server (seat, session_type);
1344     if (!display_server)
1345         return NULL;
1346
1347     seat->priv->display_servers = g_list_append (seat->priv->display_servers, display_server);
1348     g_signal_connect (display_server, "ready", G_CALLBACK (display_server_ready_cb), seat);
1349     g_signal_connect (display_server, "stopped", G_CALLBACK (display_server_stopped_cb), seat);
1350
1351     return display_server;
1352 }
1353
1354 gboolean
1355 seat_switch_to_greeter (Seat *seat)
1356 {
1357     Greeter *greeter_session;
1358     DisplayServer *display_server;
1359
1360     g_return_val_if_fail (seat != NULL, FALSE);
1361
1362     if (!seat->priv->can_switch)
1363         return FALSE;
1364
1365     /* Switch to greeter if one open */
1366     greeter_session = find_greeter_session (seat);
1367     if (greeter_session)
1368     {
1369         l_debug (seat, "Switching to existing greeter");
1370         seat_set_active_session (seat, SESSION (greeter_session));
1371         return TRUE;
1372     }
1373
1374     greeter_session = create_greeter_session (seat);
1375     if (!greeter_session)
1376         return FALSE;
1377
1378     if (seat->priv->session_to_activate)
1379         g_object_unref (seat->priv->session_to_activate);
1380     seat->priv->session_to_activate = g_object_ref (greeter_session);
1381
1382     display_server = create_display_server (seat, session_get_session_type (SESSION (greeter_session)));
1383     session_set_display_server (SESSION (greeter_session), display_server);
1384     if (!display_server_start (display_server))
1385         return FALSE;
1386
1387     return TRUE;
1388 }
1389
1390 static void
1391 switch_authentication_complete_cb (Session *session, Seat *seat)
1392 {
1393     Greeter *greeter_session;
1394     DisplayServer *display_server;
1395     gboolean existing = FALSE;
1396
1397     /* If authenticated, then unlock existing session or start new one */
1398     if (session_get_is_authenticated (session))
1399     {
1400         Session *s;
1401
1402         s = find_user_session (seat, session_get_username (session), session);
1403         if (s)
1404         {
1405             l_debug (seat, "Session authenticated, switching to existing user session");
1406             session_unlock (s);
1407             seat_set_active_session (seat, s);
1408             session_stop (session);
1409         }
1410         else
1411         {
1412             l_debug (seat, "Session authenticated, starting display server");
1413             if (seat->priv->session_to_activate)
1414                 g_object_unref (seat->priv->session_to_activate);
1415             seat->priv->session_to_activate = g_object_ref (session);
1416             display_server = create_display_server (seat, session_get_session_type (session));
1417             session_set_display_server (session, display_server);
1418             display_server_start (display_server);
1419         }
1420
1421         return;
1422     }
1423
1424     session_stop (session);
1425
1426     /* See if we already have a greeter up and reuse it if so */
1427     greeter_session = find_resettable_greeter (seat);
1428     if (greeter_session)
1429     {
1430         l_debug (seat, "Switching to existing greeter to authenticate session");
1431         set_greeter_hints (seat, greeter_session);
1432         existing = TRUE;
1433     }
1434     else
1435     {
1436         l_debug (seat, "Starting greeter to authenticate session");
1437         greeter_session = create_greeter_session (seat);
1438     }
1439
1440     if (session_get_is_guest (session))
1441         greeter_set_hint (greeter_session, "select-guest", "true");
1442     else
1443         greeter_set_hint (greeter_session, "select-user", session_get_username (session));
1444
1445     if (existing)
1446     {
1447         greeter_reset (greeter_session);
1448         seat_set_active_session (seat, SESSION (greeter_session));
1449     }
1450     else
1451     {
1452         if (seat->priv->session_to_activate)
1453             g_object_unref (seat->priv->session_to_activate);
1454         seat->priv->session_to_activate = g_object_ref (greeter_session);
1455
1456         display_server = create_display_server (seat, session_get_session_type (SESSION (greeter_session)));
1457         session_set_display_server (SESSION (greeter_session), display_server);
1458         display_server_start (display_server);
1459     }
1460 }
1461
1462 gboolean
1463 seat_switch_to_user (Seat *seat, const gchar *username, const gchar *session_name)
1464 {
1465     Session *session;
1466
1467     g_return_val_if_fail (seat != NULL, FALSE);
1468     g_return_val_if_fail (username != NULL, FALSE);
1469
1470     if (!seat->priv->can_switch)
1471         return FALSE;
1472
1473     /* If we're already on this session, then ignore */
1474     session = find_user_session (seat, username, NULL);
1475     if (session && session == seat->priv->active_session)
1476         return TRUE;
1477
1478     l_debug (seat, "Switching to user %s", username);
1479
1480     /* Attempt to authenticate them */
1481     session = create_user_session (seat, username, FALSE);
1482     g_signal_connect (session, "authentication-complete", G_CALLBACK (switch_authentication_complete_cb), seat);
1483     session_set_pam_service (session, seat_get_string_property (seat, "pam-service"));
1484     session_start (session);
1485
1486     return FALSE;
1487 }
1488
1489 static Session *
1490 find_guest_session (Seat *seat)
1491 {
1492     GList *link;
1493
1494     for (link = seat->priv->sessions; link; link = link->next)
1495     {
1496         Session *session = link->data;
1497         if (!session_get_is_stopping (session) && session_get_is_guest (session))
1498             return session;
1499     }
1500
1501     return NULL;
1502 }
1503
1504 gboolean
1505 seat_switch_to_guest (Seat *seat, const gchar *session_name)
1506 {
1507     Session *session;
1508     DisplayServer *display_server;
1509
1510     g_return_val_if_fail (seat != NULL, FALSE);
1511
1512     if (!seat->priv->can_switch || !seat_get_allow_guest (seat))
1513         return FALSE;
1514
1515     /* Switch to session if one open */
1516     session = find_guest_session (seat);
1517     if (session)
1518     {
1519         l_debug (seat, "Switching to existing guest account %s", session_get_username (session));
1520         seat_set_active_session (seat, session);
1521         return TRUE;
1522     }
1523
1524     session = create_guest_session (seat, session_name);
1525     if (!session)
1526         return FALSE;
1527
1528     display_server = create_display_server (seat, session_get_session_type (session));
1529
1530     if (seat->priv->session_to_activate)
1531         g_object_unref (seat->priv->session_to_activate);
1532     seat->priv->session_to_activate = g_object_ref (session);
1533     session_set_pam_service (session, seat_get_string_property (seat, "pam-autologin-service"));
1534     session_set_display_server (session, display_server);
1535
1536     return display_server_start (display_server);
1537 }
1538
1539 gboolean
1540 seat_lock (Seat *seat, const gchar *username)
1541 {
1542     Greeter *greeter_session;
1543     DisplayServer *display_server;
1544     gboolean existing = FALSE;
1545
1546     g_return_val_if_fail (seat != NULL, FALSE);
1547
1548     if (!seat->priv->can_switch)
1549         return FALSE;
1550
1551     l_debug (seat, "Locking");
1552
1553     /* Switch to greeter we can reuse */
1554     greeter_session = find_resettable_greeter (seat);
1555     if (greeter_session)
1556     {
1557         l_debug (seat, "Switching to existing greeter");
1558         set_greeter_hints (seat, greeter_session);
1559         existing = TRUE;
1560     }
1561     else
1562     {
1563         greeter_session = create_greeter_session (seat);
1564         if (!greeter_session)
1565             return FALSE;
1566     }
1567
1568     greeter_set_hint (greeter_session, "lock-screen", "true");
1569     if (username)
1570         greeter_set_hint (greeter_session, "select-user", username);
1571
1572     if (existing)
1573     {
1574         greeter_reset (greeter_session);
1575         seat_set_active_session (seat, SESSION (greeter_session));
1576         return TRUE;
1577     }
1578     else
1579     {
1580         display_server = create_display_server (seat, session_get_session_type (SESSION (greeter_session)));
1581
1582         if (seat->priv->session_to_activate)
1583             g_object_unref (seat->priv->session_to_activate);
1584         seat->priv->session_to_activate = g_object_ref (greeter_session);
1585         session_set_display_server (SESSION (greeter_session), display_server);
1586
1587         return display_server_start (display_server);
1588     }
1589 }
1590
1591 void
1592 seat_stop (Seat *seat)
1593 {
1594     g_return_if_fail (seat != NULL);
1595
1596     if (seat->priv->stopping)
1597         return;
1598
1599     l_debug (seat, "Stopping");
1600     seat->priv->stopping = TRUE;
1601     SEAT_GET_CLASS (seat)->stop (seat);
1602 }
1603
1604 gboolean
1605 seat_get_is_stopping (Seat *seat)
1606 {
1607     g_return_val_if_fail (seat != NULL, FALSE);
1608     return seat->priv->stopping;
1609 }
1610
1611 static gboolean
1612 seat_real_get_start_local_sessions (Seat *seat)
1613 {
1614     return TRUE;
1615 }
1616
1617 static void
1618 seat_real_setup (Seat *seat)
1619 {
1620 }
1621
1622 static gboolean
1623 seat_real_start (Seat *seat)
1624 {
1625     const gchar *autologin_username;
1626     int autologin_timeout;
1627     gboolean autologin_guest;
1628     gboolean autologin_in_background;
1629     Session *session = NULL, *background_session = NULL;
1630
1631     l_debug (seat, "Starting");
1632
1633     /* If this display server doesn't have a session running on it, just start it */
1634     if (!get_start_local_sessions (seat))
1635     {
1636         DisplayServer *display_server;
1637         display_server = create_display_server (seat, "x"); // FIXME: Not necessarily an X seat, but not sure what to put here
1638         return display_server_start (display_server);
1639     }
1640
1641     /* Get autologin settings */
1642     autologin_username = seat_get_string_property (seat, "autologin-user");
1643     if (g_strcmp0 (autologin_username, "") == 0)
1644         autologin_username = NULL;
1645     autologin_timeout = seat_get_integer_property (seat, "autologin-user-timeout");
1646     autologin_guest = seat_get_boolean_property (seat, "autologin-guest");
1647     autologin_in_background = seat_get_boolean_property (seat, "autologin-in-background");
1648
1649     /* Autologin if configured */
1650     if (autologin_timeout == 0 || autologin_in_background)
1651     {
1652         if (autologin_guest)
1653             session = create_guest_session (seat, NULL);
1654         else if (autologin_username != NULL)
1655             session = create_user_session (seat, autologin_username, TRUE);
1656
1657         if (session)
1658             session_set_pam_service (session, seat_get_string_property (seat, "pam-autologin-service"));
1659
1660         /* Load in background if required */
1661         if (autologin_in_background && session)
1662         {
1663             background_session = session;
1664             session = NULL;
1665         }
1666
1667         if (session)
1668         {
1669             DisplayServer *display_server;
1670
1671             if (seat->priv->session_to_activate)
1672                 g_object_unref (seat->priv->session_to_activate);
1673             seat->priv->session_to_activate = g_object_ref (session);
1674
1675             display_server = create_display_server (seat, session_get_session_type (session));
1676             session_set_display_server (session, display_server);
1677             if (!display_server || !display_server_start (display_server))
1678             {
1679                 l_debug (seat, "Can't create display server for automatic login");
1680                 session_stop (session);
1681                 if (display_server)
1682                     display_server_stop (display_server);
1683                 session = NULL;
1684             }
1685         }
1686     }
1687
1688     /* Fallback to a greeter */
1689     if (!session)
1690     {
1691         Greeter *greeter_session;
1692         DisplayServer *display_server;
1693
1694         greeter_session = create_greeter_session (seat);
1695         if (!greeter_session)
1696         {
1697             l_debug (seat, "Failed to create greeter session");
1698             return FALSE;
1699         }
1700
1701         if (seat->priv->session_to_activate)
1702             g_object_unref (seat->priv->session_to_activate);
1703         seat->priv->session_to_activate = g_object_ref (greeter_session);
1704         session = SESSION (greeter_session);
1705
1706         display_server = create_display_server (seat, session_get_session_type (session));
1707         session_set_display_server (session, display_server);
1708         if (!display_server || !display_server_start (display_server))
1709         {
1710             l_debug (seat, "Can't create display server for greeter");
1711             session_stop (session);
1712             if (display_server)
1713                 display_server_stop (display_server);
1714             session = NULL;
1715         }
1716     }
1717
1718     /* Fail if can't start a session */
1719     if (!session)
1720     {
1721         seat_stop (seat);
1722         return FALSE;
1723     }
1724
1725     /* Start background session */
1726     if (background_session)
1727     {
1728         DisplayServer *background_display_server;
1729
1730         background_display_server = create_display_server (seat, session_get_session_type (background_session));
1731         session_set_display_server (background_session, background_display_server);
1732         if (!display_server_start (background_display_server))
1733             l_warning (seat, "Failed to start display server for background session");
1734     }
1735
1736     seat->priv->started = TRUE;
1737     return TRUE;
1738 }
1739
1740 static Greeter *
1741 seat_real_create_greeter_session (Seat *seat)
1742 {
1743     return greeter_new ();
1744 }
1745
1746 static Session *
1747 seat_real_create_session (Seat *seat)
1748 {
1749     return session_new ();
1750 }
1751
1752 static void
1753 seat_real_set_active_session (Seat *seat, Session *session)
1754 {
1755 }
1756
1757 static void
1758 seat_real_set_next_session (Seat *seat, Session *session)
1759 {
1760 }
1761
1762 static Session *
1763 seat_real_get_active_session (Seat *seat)
1764 {
1765     return NULL;
1766 }
1767
1768 static void
1769 seat_real_stop (Seat *seat)
1770 {
1771     GList *list, *link;
1772
1773     check_stopped (seat);
1774     if (seat->priv->stopped)
1775         return;
1776
1777     /* Stop all the display servers and sessions on the seat. Copy the list as
1778      * it might be modified if a display server / session stops during this loop */
1779     list = g_list_copy (seat->priv->display_servers);
1780     for (link = list; link; link = link->next)
1781         g_object_ref (link->data);
1782     for (link = list; link; link = link->next)
1783     {
1784         DisplayServer *display_server = link->data;
1785         if (!display_server_get_is_stopping (display_server))
1786         {
1787             l_debug (seat, "Stopping display server");
1788             display_server_stop (display_server);
1789         }
1790     }
1791     g_list_free_full (list, g_object_unref);
1792     list = g_list_copy (seat->priv->sessions);
1793     for (link = list; link; link = link->next)
1794         g_object_ref (link->data);
1795     for (link = list; link; link = link->next)
1796     {
1797         Session *session = link->data;
1798         if (!session_get_is_stopping (session))
1799         {
1800             l_debug (seat, "Stopping session");
1801             session_stop (session);
1802         }
1803     }
1804     g_list_free_full (list, g_object_unref);
1805 }
1806
1807 static void
1808 seat_init (Seat *seat)
1809 {
1810     seat->priv = G_TYPE_INSTANCE_GET_PRIVATE (seat, SEAT_TYPE, SeatPrivate);
1811     seat->priv->properties = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, g_free);
1812     seat->priv->share_display_server = TRUE;
1813 }
1814
1815 static void
1816 seat_finalize (GObject *object)
1817 {
1818     Seat *self;
1819     GList *link;
1820
1821     self = SEAT (object);
1822
1823     g_hash_table_unref (self->priv->properties);
1824     for (link = self->priv->display_servers; link; link = link->next)
1825     {
1826         DisplayServer *display_server = link->data;
1827         g_signal_handlers_disconnect_matched (display_server, G_SIGNAL_MATCH_DATA, 0, 0, NULL, NULL, self);
1828     }
1829     g_list_free_full (self->priv->display_servers, g_object_unref);
1830     for (link = self->priv->sessions; link; link = link->next)
1831     {
1832         Session *session = link->data;
1833         g_signal_handlers_disconnect_matched (session, G_SIGNAL_MATCH_DATA, 0, 0, NULL, NULL, self);
1834     }
1835     g_list_free_full (self->priv->sessions, g_object_unref);
1836     if (self->priv->active_session)
1837         g_object_unref (self->priv->active_session);
1838     if (self->priv->next_session)
1839         g_object_unref (self->priv->next_session);
1840     if (self->priv->session_to_activate)
1841         g_object_unref (self->priv->session_to_activate);
1842
1843     G_OBJECT_CLASS (seat_parent_class)->finalize (object);
1844 }
1845
1846 static void
1847 seat_class_init (SeatClass *klass)
1848 {
1849     GObjectClass *object_class = G_OBJECT_CLASS (klass);
1850
1851     klass->get_start_local_sessions = seat_real_get_start_local_sessions;
1852     klass->setup = seat_real_setup;
1853     klass->start = seat_real_start;
1854     klass->create_greeter_session = seat_real_create_greeter_session;
1855     klass->create_session = seat_real_create_session;
1856     klass->set_active_session = seat_real_set_active_session;
1857     klass->get_active_session = seat_real_get_active_session;
1858     klass->set_next_session = seat_real_set_next_session;
1859     klass->run_script = seat_real_run_script;
1860     klass->stop = seat_real_stop;
1861
1862     object_class->finalize = seat_finalize;
1863
1864     g_type_class_add_private (klass, sizeof (SeatPrivate));
1865
1866     signals[SESSION_ADDED] =
1867         g_signal_new ("session-added",
1868                       G_TYPE_FROM_CLASS (klass),
1869                       G_SIGNAL_RUN_LAST,
1870                       G_STRUCT_OFFSET (SeatClass, session_added),
1871                       NULL, NULL,
1872                       NULL,
1873                       G_TYPE_NONE, 1, SESSION_TYPE);
1874     signals[RUNNING_USER_SESSION] =
1875         g_signal_new ("running-user-session",
1876                       G_TYPE_FROM_CLASS (klass),
1877                       G_SIGNAL_RUN_LAST,
1878                       G_STRUCT_OFFSET (SeatClass, running_user_session),
1879                       NULL, NULL,
1880                       NULL,
1881                       G_TYPE_NONE, 1, SESSION_TYPE);
1882     signals[SESSION_REMOVED] =
1883         g_signal_new ("session-removed",
1884                       G_TYPE_FROM_CLASS (klass),
1885                       G_SIGNAL_RUN_LAST,
1886                       G_STRUCT_OFFSET (SeatClass, session_removed),
1887                       NULL, NULL,
1888                       NULL,
1889                       G_TYPE_NONE, 1, SESSION_TYPE);
1890     signals[STOPPED] =
1891         g_signal_new ("stopped",
1892                       G_TYPE_FROM_CLASS (klass),
1893                       G_SIGNAL_RUN_LAST,
1894                       G_STRUCT_OFFSET (SeatClass, stopped),
1895                       NULL, NULL,
1896                       NULL,
1897                       G_TYPE_NONE, 0);
1898 }
1899
1900 static gint
1901 seat_real_logprefix (Logger *self, gchar *buf, gulong buflen)
1902 {
1903     Seat *seat = SEAT (self);
1904     const gchar *name = seat_get_string_property (seat, "seat-name");
1905     if (name)
1906         return g_snprintf (buf, buflen, "Seat %s: ", name);
1907     else
1908         return g_snprintf (buf, buflen, "Seat: ");
1909 }
1910
1911 static void
1912 seat_logger_iface_init (LoggerInterface *iface)
1913 {
1914     iface->logprefix = &seat_real_logprefix;
1915 }