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 /* PAM services to use */
  68 #define GREETER_SERVICE   "lightdm-greeter"
  69 #define USER_SERVICE      "lightdm"
  70 #define AUTOLOGIN_SERVICE "lightdm-autologin"
  71
  72 static void seat_logger_iface_init (LoggerInterface *iface);
  73
  74 G_DEFINE_TYPE_WITH_CODE (Seat, seat, G_TYPE_OBJECT,
  75                          G_IMPLEMENT_INTERFACE (
  76                              LOGGER_TYPE, seat_logger_iface_init));
  77
  78 typedef struct
  79 {
  80     const gchar *name;
  81     GType type;
  82 } SeatModule;
  83 static GHashTable *seat_modules = NULL;
  84
  85 // FIXME: Make a get_display_server() that re-uses display servers if supported
  86 static DisplayServer *create_display_server (Seat *seat, const gchar *session_type);
  87 static Greeter *create_greeter_session (Seat *seat);
  88 static void start_session (Seat *seat, Session *session);
  89
  90 void
  91 seat_register_module (const gchar *name, GType type)
  92 {
  93     SeatModule *module;
  94
  95     if (!seat_modules)
  96         seat_modules = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, NULL);
  97
  98     g_debug ("Registered seat module %s", name);
  99
 100     module = g_malloc0 (sizeof (SeatModule));
 101     module->name = g_strdup (name);
 102     module->type = type;
 103     g_hash_table_insert (seat_modules, g_strdup (name), module);
 104 }
 105
 106 Seat *
 107 seat_new (const gchar *module_name)
 108 {
 109     Seat *seat;
 110     SeatModule *m = NULL;
 111
 112     g_return_val_if_fail (module_name != NULL, NULL);
 113
 114     if (seat_modules)
 115         m = g_hash_table_lookup (seat_modules, module_name);
 116     if (!m)
 117         return NULL;
 118
 119     seat = g_object_new (m->type, NULL);
 120
 121     return seat;
 122 }
 123
 124 void
 125 seat_set_property (Seat *seat, const gchar *name, const gchar *value)
 126 {
 127     g_return_if_fail (seat != NULL);
 128     g_hash_table_insert (seat->priv->properties, g_strdup (name), g_strdup (value));
 129 }
 130
 131 const gchar *
 132 seat_get_string_property (Seat *seat, const gchar *name)
 133 {
 134     g_return_val_if_fail (seat != NULL, NULL);
 135     return g_hash_table_lookup (seat->priv->properties, name);
 136 }
 137
 138 gchar **
 139 seat_get_string_list_property (Seat *seat, const gchar *name)
 140 {
 141     g_return_val_if_fail (seat != NULL, NULL);
 142     return g_strsplit (g_hash_table_lookup (seat->priv->properties, name), ";", 0);
 143 }
 144
 145 gboolean
 146 seat_get_boolean_property (Seat *seat, const gchar *name)
 147 {
 148     return g_strcmp0 (seat_get_string_property (seat, name), "true") == 0;
 149 }
 150
 151 gint
 152 seat_get_integer_property (Seat *seat, const gchar *name)
 153 {
 154     const gchar *value;
 155
 156     value = seat_get_string_property (seat, name);
 157     return value ? atoi (value) : 0;
 158 }
 159
 160 const gchar *
 161 seat_get_name (Seat *seat)
 162 {
 163     const gchar *name;
 164
 165     name = seat_get_string_property (seat, "xdg-seat");
 166     if (name)
 167         return name;
 168
 169     return "seat0";
 170 }
 171
 172 void
 173 seat_set_can_switch (Seat *seat, gboolean can_switch)
 174 {
 175     g_return_if_fail (seat != NULL);
 176
 177     seat->priv->can_switch = can_switch;
 178 }
 179
 180 void
 181 seat_set_share_display_server (Seat *seat, gboolean share_display_server)
 182 {
 183     g_return_if_fail (seat != NULL);
 184
 185     seat->priv->share_display_server = share_display_server;
 186 }
 187
 188 gboolean
 189 seat_start (Seat *seat)
 190 {
 191     g_return_val_if_fail (seat != NULL, FALSE);
 192
 193     SEAT_GET_CLASS (seat)->setup (seat);
 194     return SEAT_GET_CLASS (seat)->start (seat);
 195 }
 196
 197 GList *
 198 seat_get_sessions (Seat *seat)
 199 {
 200     g_return_val_if_fail (seat != NULL, NULL);
 201     return seat->priv->sessions;
 202 }
 203
 204 void
 205 seat_set_active_session (Seat *seat, Session *session)
 206 {
 207     GList *link;
 208
 209     g_return_if_fail (seat != NULL);
 210
 211     SEAT_GET_CLASS (seat)->set_active_session (seat, session);
 212
 213     /* Stop any greeters */
 214     for (link = seat->priv->sessions; link; link = link->next)
 215     {
 216         Session *s = link->data;
 217
 218         if (s == session || session_get_is_stopping (s))
 219             continue;
 220
 221         if (IS_GREETER (s))
 222         {
 223             Greeter *greeter = GREETER (s);
 224             if (greeter_get_resettable (greeter))
 225             {
 226                 l_debug (seat, "Idling greeter");
 227                 greeter_idle (greeter);
 228             }
 229             else
 230             {
 231                 l_debug (seat, "Stopping greeter");
 232                 session_stop (s);
 233             }
 234         }
 235     }
 236
 237     /* Lock previous sessions */
 238     if (seat->priv->active_session)
 239     {
 240         if (session != seat->priv->active_session && !IS_GREETER (seat->priv->active_session))
 241             session_lock (seat->priv->active_session);
 242         g_object_unref (seat->priv->active_session);
 243     }
 244
 245     session_activate (session);
 246     seat->priv->active_session = g_object_ref (session);
 247 }
 248
 249 Session *
 250 seat_get_active_session (Seat *seat)
 251 {
 252     g_return_val_if_fail (seat != NULL, NULL);
 253     return SEAT_GET_CLASS (seat)->get_active_session (seat);
 254 }
 255
 256 Session *
 257 seat_get_next_session (Seat *seat)
 258 {
 259     g_return_val_if_fail (seat != NULL, NULL);
 260     return seat->priv->next_session;
 261 }
 262
 263 gboolean
 264 seat_get_can_switch (Seat *seat)
 265 {
 266     g_return_val_if_fail (seat != NULL, FALSE);
 267     return seat->priv->can_switch;
 268 }
 269
 270 gboolean
 271 seat_get_allow_guest (Seat *seat)
 272 {
 273     g_return_val_if_fail (seat != NULL, FALSE);
 274     return seat_get_boolean_property (seat, "allow-guest") && guest_account_is_installed ();
 275 }
 276
 277 static gboolean
 278 run_script (Seat *seat, DisplayServer *display_server, const gchar *script_name, User *user)
 279 {
 280     Process *script;
 281     gboolean result = FALSE;
 282
 283     script = process_new (NULL, NULL);
 284
 285     process_set_command (script, script_name);
 286
 287     /* Set POSIX variables */
 288     process_set_clear_environment (script, TRUE);
 289     process_set_env (script, "SHELL", "/bin/sh");
 290
 291     /* Variables required for regression tests */
 292     if (g_getenv ("LIGHTDM_TEST_ROOT"))
 293     {
 294         process_set_env (script, "LIGHTDM_TEST_ROOT", g_getenv ("LIGHTDM_TEST_ROOT"));
 295         process_set_env (script, "LD_PRELOAD", g_getenv ("LD_PRELOAD"));
 296         process_set_env (script, "LD_LIBRARY_PATH", g_getenv ("LD_LIBRARY_PATH"));
 297         process_set_env (script, "PATH", g_getenv ("PATH"));
 298     }
 299     else
 300         process_set_env (script, "PATH", "/usr/local/bin:/usr/bin:/bin");
 301
 302     if (user)
 303     {
 304         process_set_env (script, "USER", user_get_name (user));
 305         process_set_env (script, "LOGNAME", user_get_name (user));
 306         process_set_env (script, "HOME", user_get_home_directory (user));
 307     }
 308     else
 309         process_set_env (script, "HOME", "/");
 310
 311     SEAT_GET_CLASS (seat)->run_script (seat, display_server, script);
 312
 313     if (process_start (script, TRUE))
 314     {
 315         int exit_status;
 316
 317         exit_status = process_get_exit_status (script);
 318         if (WIFEXITED (exit_status))
 319         {
 320             l_debug (seat, "Exit status of %s: %d", script_name, WEXITSTATUS (exit_status));
 321             result = WEXITSTATUS (exit_status) == EXIT_SUCCESS;
 322         }
 323     }
 324
 325     g_object_unref (script);
 326
 327     return result;
 328 }
 329
 330 static void
 331 seat_real_run_script (Seat *seat, DisplayServer *display_server, Process *process)
 332 {
 333 }
 334
 335 static void
 336 emit_upstart_signal (const gchar *signal)
 337 {
 338     g_return_if_fail (signal != NULL);
 339     g_return_if_fail (signal[0] != 0);
 340
 341     if (getuid () != 0)
 342         return;
 343
 344     gchar *cmd = g_strdup_printf ("initctl -q emit %s DISPLAY_MANAGER=lightdm", signal);
 345     g_spawn_command_line_async (cmd, NULL); /* OK if it fails, probably not installed */
 346     g_free (cmd);
 347 }
 348
 349 static void
 350 check_stopped (Seat *seat)
 351 {
 352     if (seat->priv->stopping &&
 353         !seat->priv->stopped &&
 354         g_list_length (seat->priv->display_servers) == 0 &&
 355         g_list_length (seat->priv->sessions) == 0)
 356     {
 357         seat->priv->stopped = TRUE;
 358         l_debug (seat, "Stopped");
 359         g_signal_emit (seat, signals[STOPPED], 0);
 360     }
 361 }
 362
 363 static gboolean
 364 get_start_local_sessions (Seat *seat)
 365 {
 366     return SEAT_GET_CLASS (seat)->get_start_local_sessions (seat);
 367 }
 368
 369 static void
 370 display_server_stopped_cb (DisplayServer *display_server, Seat *seat)
 371 {
 372     const gchar *script;
 373     GList *list, *link;
 374     Session *active_session;
 375
 376     l_debug (seat, "Display server stopped");
 377
 378     /* Run a script right after stopping the display server */
 379     script = seat_get_string_property (seat, "display-stopped-script");
 380     if (script)
 381         run_script (seat, NULL, script, NULL);
 382
 383     g_signal_handlers_disconnect_matched (display_server, G_SIGNAL_MATCH_DATA, 0, 0, NULL, NULL, seat);
 384     seat->priv->display_servers = g_list_remove (seat->priv->display_servers, display_server);
 385
 386     if (seat->priv->stopping || !seat->priv->started)
 387     {
 388         check_stopped (seat);
 389         g_object_unref (display_server);
 390         return;
 391     }
 392
 393     /* Stop all sessions on this display server */
 394     list = g_list_copy (seat->priv->sessions);
 395     for (link = list; link; link = link->next)
 396         g_object_ref (link->data);
 397     for (link = list; link; link = link->next)
 398     {
 399         Session *session = link->data;
 400
 401         if (session_get_display_server (session) != display_server || session_get_is_stopping (session))
 402             continue;
 403
 404         /* Stop seat if this is the only display server and it failed to start a greeter */
 405         if (IS_GREETER (session) &&
 406             !session_get_is_started (session) &&
 407             g_list_length (seat->priv->display_servers) == 0)
 408         {
 409             l_debug (seat, "Stopping; greeter display server failed to start");
 410             seat_stop (seat);
 411         }
 412
 413         l_debug (seat, "Stopping session");
 414         session_stop (session);
 415     }
 416     g_list_free_full (list, g_object_unref);
 417
 418     if (!seat->priv->stopping && get_start_local_sessions (seat))
 419     {
 420         /* If we were the active session, switch to a greeter */
 421         active_session = seat_get_active_session (seat);
 422         if (!active_session || session_get_display_server (active_session) == display_server)
 423         {
 424             l_debug (seat, "Active display server stopped, starting greeter");
 425             if (!seat_switch_to_greeter (seat))
 426             {
 427                 l_debug (seat, "Stopping; failed to start a greeter");
 428                 seat_stop (seat);
 429             }
 430         }
 431     }
 432
 433     g_object_unref (display_server);
 434 }
 435
 436 static gboolean
 437 can_share_display_server (Seat *seat, DisplayServer *display_server)
 438 {
 439     return seat->priv->share_display_server && display_server_get_can_share (display_server);
 440 }
 441
 442 static Greeter *
 443 find_greeter_session (Seat *seat)
 444 {
 445     GList *link;
 446
 447     for (link = seat->priv->sessions; link; link = link->next)
 448     {
 449         Session *session = link->data;
 450         if (!session_get_is_stopping (session) && IS_GREETER (session))
 451             return GREETER (session);
 452     }
 453
 454     return NULL;
 455 }
 456
 457 static void
 458 reset_greeter_hints (Seat *seat, Greeter *greeter_session)
 459 {
 460     greeter_clear_hints (greeter_session);
 461     greeter_set_hint (greeter_session, "default-session", seat_get_string_property (seat, "user-session"));
 462     greeter_set_hint (greeter_session, "hide-users", seat_get_boolean_property (seat, "greeter-hide-users") ? "true" : "false");
 463     greeter_set_hint (greeter_session, "show-manual-login", seat_get_boolean_property (seat, "greeter-show-manual-login") ? "true" : "false");
 464     greeter_set_hint (greeter_session, "show-remote-login", seat_get_boolean_property (seat, "greeter-show-remote-login") ? "true" : "false");
 465     greeter_set_hint (greeter_session, "has-guest-account", seat_get_allow_guest (seat) && seat_get_boolean_property (seat, "greeter-allow-guest") ? "true" : "false");
 466 }
 467
 468 static void
 469 switch_to_greeter_from_failed_session (Seat *seat, Session *session)
 470 {
 471     Greeter *greeter_session;
 472     gboolean existing = FALSE;
 473
 474     /* Switch to greeter if one open */
 475     greeter_session = find_greeter_session (seat);
 476     if (greeter_session)
 477     {
 478         l_debug (seat, "Switching to existing greeter");
 479         reset_greeter_hints (seat, greeter_session);
 480         existing = TRUE;
 481     }
 482     else
 483     {
 484         greeter_session = create_greeter_session (seat);
 485     }
 486
 487     if (session_get_is_guest (session))
 488         greeter_set_hint (greeter_session, "select-guest", "true");
 489     else
 490         greeter_set_hint (greeter_session, "select-user", session_get_username (session));
 491
 492     if (existing)
 493     {
 494         greeter_reset (greeter_session);
 495         seat_set_active_session (seat, SESSION (greeter_session));
 496     }
 497     else
 498     {
 499         if (seat->priv->session_to_activate)
 500             g_object_unref (seat->priv->session_to_activate);
 501         seat->priv->session_to_activate = g_object_ref (greeter_session);
 502
 503         if (can_share_display_server (seat, session_get_display_server (session)))
 504             session_set_display_server (SESSION (greeter_session), session_get_display_server (session));
 505         else
 506         {
 507             DisplayServer *display_server;
 508
 509             display_server = create_display_server (seat, session_get_session_type (session));
 510             session_set_display_server (session, display_server);
 511             if (!display_server_start (display_server))
 512             {
 513                 l_debug (seat, "Failed to start display server for greeter");
 514                 seat_stop (seat);
 515             }
 516         }
 517
 518         start_session (seat, SESSION (greeter_session));
 519     }
 520
 521     /* Stop failed session */
 522     session_stop (session);
 523 }
 524
 525 static void
 526 start_session (Seat *seat, Session *session)
 527 {
 528     /* Use system location for greeter log file */
 529     if (IS_GREETER (session))
 530     {
 531         gchar *log_dir, *filename, *log_filename;
 532
 533         log_dir = config_get_string (config_get_instance (), "LightDM", "log-directory");
 534         filename = g_strdup_printf ("%s-greeter.log", display_server_get_name (session_get_display_server (session)));
 535         log_filename = g_build_filename (log_dir, filename, NULL);
 536         g_free (log_dir);
 537         g_free (filename);
 538         session_set_log_file (session, log_filename);
 539         g_free (log_filename);
 540     }
 541
 542     if (session_start (session))
 543         return;
 544
 545     if (IS_GREETER (session))
 546     {
 547         l_debug (seat, "Failed to start greeter");
 548         display_server_stop (session_get_display_server (session));
 549         return;
 550     }
 551
 552     l_debug (seat, "Failed to start session, starting greeter");
 553     switch_to_greeter_from_failed_session (seat, session);
 554 }
 555
 556 static void
 557 run_session (Seat *seat, Session *session)
 558 {
 559     const gchar *script;
 560
 561     if (IS_GREETER (session))
 562         script = seat_get_string_property (seat, "greeter-setup-script");
 563     else
 564         script = seat_get_string_property (seat, "session-setup-script");
 565     if (script && !run_script (seat, session_get_display_server (session), script, session_get_user (session)))
 566     {
 567         l_debug (seat, "Switching to greeter due to failed setup script");
 568         switch_to_greeter_from_failed_session (seat, session);
 569         return;
 570     }
 571
 572     if (!IS_GREETER (session))
 573     {
 574         g_signal_emit (seat, signals[RUNNING_USER_SESSION], 0, session);
 575         emit_upstart_signal ("desktop-session-start");
 576     }
 577
 578     session_run (session);
 579
 580     // FIXME: Wait until the session is ready
 581
 582     if (session == seat->priv->session_to_activate)
 583     {
 584         seat_set_active_session (seat, session);
 585         g_object_unref (seat->priv->session_to_activate);
 586         seat->priv->session_to_activate = NULL;
 587     }
 588     else if (seat->priv->active_session)
 589     {
 590         /* Multiple sessions can theoretically be on the same VT (especially
 591            if using Mir).  If a new session appears on an existing active VT,
 592            logind will mark it as active, while ConsoleKit will re-mark the
 593            oldest session as active.  In either case, that may not be the
 594            session that we want to be active.  So let's be explicit and
 595            re-activate the correct session whenever a new session starts.
 596            There's no harm to do this in seats that enforce separate VTs. */
 597         session_activate (seat->priv->active_session);
 598     }
 599 }
 600
 601 static Session *
 602 find_user_session (Seat *seat, const gchar *username, Session *ignore_session)
 603 {
 604     GList *link;
 605
 606     if (!username)
 607         return NULL;
 608
 609     for (link = seat->priv->sessions; link; link = link->next)
 610     {
 611         Session *session = link->data;
 612
 613         if (session == ignore_session)
 614             continue;
 615
 616         if (!session_get_is_stopping (session) && g_strcmp0 (session_get_username (session), username) == 0)
 617             return session;
 618     }
 619
 620     return NULL;
 621 }
 622
 623 static void
 624 greeter_active_username_changed_cb (Greeter *greeter, GParamSpec *pspec, Seat *seat)
 625 {
 626     Session *session;
 627
 628     session = find_user_session (seat, greeter_get_active_username (greeter), seat->priv->active_session);
 629
 630     if (seat->priv->next_session)
 631         g_object_unref (seat->priv->next_session);
 632     seat->priv->next_session = session ? g_object_ref (session) : NULL;
 633
 634     SEAT_GET_CLASS (seat)->set_next_session (seat, session);
 635 }
 636
 637 static void
 638 session_authentication_complete_cb (Session *session, Seat *seat)
 639 {
 640     if (session_get_is_authenticated (session))
 641     {
 642         Session *s;
 643
 644         s = find_user_session (seat, session_get_username (session), session);
 645         if (s)
 646         {
 647             l_debug (seat, "Session authenticated, switching to existing user session");
 648             seat_set_active_session (seat, s);
 649             session_stop (session);
 650         }
 651         else
 652         {
 653             l_debug (seat, "Session authenticated, running command");
 654             run_session (seat, session);
 655         }
 656     }
 657     else if (!IS_GREETER (session))
 658     {
 659         l_debug (seat, "Switching to greeter due to failed authentication");
 660         switch_to_greeter_from_failed_session (seat, session);
 661     }
 662     else
 663     {
 664         l_debug (seat, "Stopping session that failed authentication");
 665         session_stop (session);
 666     }
 667 }
 668
 669 static void
 670 session_stopped_cb (Session *session, Seat *seat)
 671 {
 672     DisplayServer *display_server;
 673
 674     l_debug (seat, "Session stopped");
 675
 676     g_signal_handlers_disconnect_matched (session, G_SIGNAL_MATCH_DATA, 0, 0, NULL, NULL, seat);
 677     seat->priv->sessions = g_list_remove (seat->priv->sessions, session);
 678     if (session == seat->priv->active_session)
 679     {
 680         g_object_unref (seat->priv->active_session);
 681         seat->priv->active_session = NULL;
 682     }
 683     if (session == seat->priv->next_session)
 684     {
 685         g_object_unref (seat->priv->next_session);
 686         seat->priv->next_session = NULL;
 687     }
 688     if (session == seat->priv->session_to_activate)
 689     {
 690         g_object_unref (seat->priv->session_to_activate);
 691         seat->priv->session_to_activate = NULL;
 692     }
 693
 694     display_server = session_get_display_server (session);
 695     if (!display_server)
 696     {
 697         g_object_unref (session);
 698         return;
 699     }
 700
 701     /* Cleanup */
 702     if (!IS_GREETER (session))
 703     {
 704         const gchar *script;
 705         script = seat_get_string_property (seat, "session-cleanup-script");
 706         if (script)
 707             run_script (seat, display_server, script, session_get_user (session));
 708     }
 709
 710     /* We were waiting for this session, but it didn't start :( */
 711     // FIXME: Start a greeter on this?
 712     if (session == seat->priv->session_to_activate)
 713     {
 714         g_object_unref (seat->priv->session_to_activate);
 715         seat->priv->session_to_activate = NULL;
 716     }
 717
 718     if (seat->priv->stopping)
 719     {
 720         check_stopped (seat);
 721         g_object_unref (session);
 722         return;
 723     }
 724
 725     /* If this is the greeter session then re-use this display server */
 726     if (IS_GREETER (session) &&
 727         can_share_display_server (seat, display_server) &&
 728         greeter_get_start_session (GREETER (session)))
 729     {
 730         GList *link;
 731
 732         for (link = seat->priv->sessions; link; link = link->next)
 733         {
 734             Session *s = link->data;
 735
 736             /* Skip this session and sessions on other display servers */
 737             if (s == session || session_get_display_server (s) != display_server || session_get_is_stopping (s))
 738                 continue;
 739
 740             if (session_get_is_authenticated (s))
 741             {
 742                 l_debug (seat, "Greeter stopped, running session");
 743                 run_session (seat, s);
 744             }
 745             else
 746             {
 747                 l_debug (seat, "Greeter stopped, starting session authentication");
 748                 start_session (seat, s);
 749             }
 750             break;
 751         }
 752     }
 753     /* If this is the greeter and nothing else is running then stop the seat */
 754     else if (IS_GREETER (session) &&
 755         !greeter_get_start_session (GREETER (session)) &&
 756         g_list_length (seat->priv->display_servers) == 1 &&
 757         g_list_nth_data (seat->priv->display_servers, 0) == display_server)
 758     {
 759         l_debug (seat, "Stopping; failed to start a greeter");
 760         seat_stop (seat);
 761     }
 762     /* If we were the active session, switch to a greeter */
 763     else if (!IS_GREETER (session) && session == seat_get_active_session (seat))
 764     {
 765         l_debug (seat, "Active session stopped, starting greeter");
 766         if (!seat_switch_to_greeter (seat))
 767         {
 768             l_debug (seat, "Stopping; failed to start a greeter");
 769             seat_stop (seat);
 770         }
 771     }
 772
 773     /* Stop the display server if no-longer required */
 774     if (display_server && !display_server_get_is_stopping (display_server))
 775     {
 776         GList *link;
 777         int n_sessions = 0;
 778
 779         for (link = seat->priv->sessions; link; link = link->next)
 780         {
 781             Session *s = link->data;
 782             if (s == session)
 783                 continue;
 784             if (session_get_display_server (s) == display_server)
 785                 n_sessions++;
 786         }
 787         if (n_sessions == 0)
 788         {
 789             l_debug (seat, "Stopping display server, no sessions require it");
 790             display_server_stop (display_server);
 791         }
 792     }
 793
 794     g_signal_emit (seat, signals[SESSION_REMOVED], 0, session);
 795     g_object_unref (session);
 796 }
 797
 798 static void
 799 set_session_env (Session *session)
 800 {
 801     /* Connect using the session bus */
 802     if (getuid () != 0)
 803     {
 804         if (g_getenv ("DBUS_SESSION_BUS_ADDRESS"))
 805             session_set_env (session, "DBUS_SESSION_BUS_ADDRESS", g_getenv ("DBUS_SESSION_BUS_ADDRESS"));
 806         session_set_env (session, "LDM_BUS", "SESSION");
 807         if (g_getenv ("LD_PRELOAD"))
 808             session_set_env (session, "LD_PRELOAD", g_getenv ("LD_PRELOAD"));
 809         if (g_getenv ("LD_LIBRARY_PATH"))
 810             session_set_env (session, "LD_LIBRARY_PATH", g_getenv ("LD_LIBRARY_PATH"));
 811         if (g_getenv ("PATH"))
 812             session_set_env (session, "PATH", g_getenv ("PATH"));
 813     }
 814
 815     /* Variables required for regression tests */
 816     if (g_getenv ("LIGHTDM_TEST_ROOT"))
 817     {
 818         session_set_env (session, "LIGHTDM_TEST_ROOT", g_getenv ("LIGHTDM_TEST_ROOT"));
 819         session_set_env (session, "DBUS_SYSTEM_BUS_ADDRESS", g_getenv ("DBUS_SYSTEM_BUS_ADDRESS"));
 820         session_set_env (session, "DBUS_SESSION_BUS_ADDRESS", g_getenv ("DBUS_SESSION_BUS_ADDRESS"));
 821         session_set_env (session, "LD_PRELOAD", g_getenv ("LD_PRELOAD"));
 822         session_set_env (session, "LD_LIBRARY_PATH", g_getenv ("LD_LIBRARY_PATH"));
 823         session_set_env (session, "GI_TYPELIB_PATH", g_getenv ("GI_TYPELIB_PATH"));
 824     }
 825 }
 826
 827 static Session *
 828 create_session (Seat *seat, gboolean autostart)
 829 {
 830     Session *session;
 831
 832     session = SEAT_GET_CLASS (seat)->create_session (seat);
 833     seat->priv->sessions = g_list_append (seat->priv->sessions, session);
 834     if (autostart)
 835         g_signal_connect (session, "authentication-complete", G_CALLBACK (session_authentication_complete_cb), seat);
 836     g_signal_connect (session, "stopped", G_CALLBACK (session_stopped_cb), seat);
 837
 838     set_session_env (session);
 839
 840     g_signal_emit (seat, signals[SESSION_ADDED], 0, session);
 841
 842     return session;
 843 }
 844
 845 static gchar **
 846 get_session_argv (Seat *seat, SessionConfig *session_config, const gchar *session_wrapper)
 847 {
 848     gboolean result;
 849     int argc;
 850     gchar **argv, *path;
 851     GError *error = NULL;
 852
 853     /* If configured, run sessions through a wrapper */
 854     if (session_wrapper)
 855     {
 856         argv = g_malloc (sizeof (gchar *) * 3);
 857         path = g_find_program_in_path (session_wrapper);
 858         argv[0] = path ? path : g_strdup (session_wrapper);
 859         argv[1] = g_strdup (session_config_get_command (session_config));
 860         argv[2] = NULL;
 861         return argv;
 862     }
 863
 864     /* Split command into an array listing and make command absolute */
 865     result = g_shell_parse_argv (session_config_get_command (session_config), &argc, &argv, &error);
 866     if (error)
 867         l_debug (seat, "Invalid session command '%s': %s", session_config_get_command (session_config), error->message);
 868     g_clear_error (&error);
 869     if (!result)
 870         return NULL;
 871     path = g_find_program_in_path (argv[0]);
 872     if (path)
 873     {
 874         g_free (argv[0]);
 875         argv[0] = path;
 876     }
 877
 878     return argv;
 879 }
 880
 881 static SessionConfig *
 882 find_session_config (Seat *seat, const gchar *sessions_dir, const gchar *session_name)
 883 {
 884     gchar **dirs;
 885     SessionConfig *session_config = NULL;
 886     int i;
 887     GError *error = NULL;
 888
 889     g_return_val_if_fail (sessions_dir != NULL, NULL);
 890     g_return_val_if_fail (session_name != NULL, NULL);
 891
 892     dirs = g_strsplit (sessions_dir, ":", -1);
 893     for (i = 0; dirs[i]; i++)
 894     {
 895         gchar *filename, *path;
 896
 897         filename = g_strdup_printf ("%s.desktop", session_name);
 898         path = g_build_filename (dirs[i], filename, NULL);
 899         g_free (filename);
 900         session_config = session_config_new_from_file (path, &error);
 901         g_free (path);
 902         if (session_config)
 903             break;
 904
 905         if (dirs[i+1] == NULL)
 906             l_debug (seat, "Failed to find session configuration %s", session_name);
 907         g_clear_error (&error);
 908     }
 909     g_strfreev (dirs);
 910
 911     return session_config;
 912 }
 913
 914 static void
 915 configure_session (Session *session, SessionConfig *config, const gchar *session_name, const gchar *language)
 916 {
 917     const gchar *desktop_name;
 918
 919     session_set_session_type (session, session_config_get_session_type (config));
 920     session_set_env (session, "XDG_SESSION_DESKTOP", session_name);
 921     session_set_env (session, "DESKTOP_SESSION", session_name);
 922     session_set_env (session, "GDMSESSION", session_name);
 923     desktop_name = session_config_get_desktop_name (config);
 924     if (desktop_name)
 925         session_set_env (session, "XDG_CURRENT_DESKTOP", desktop_name);
 926     if (language && language[0] != '\0')
 927     {
 928         session_set_env (session, "LANG", language);
 929         session_set_env (session, "GDM_LANG", language);
 930     }
 931 }
 932
 933 static Session *
 934 create_user_session (Seat *seat, const gchar *username, gboolean autostart)
 935 {
 936     User *user;
 937     gchar *sessions_dir;
 938     const gchar *session_name, *language;
 939     SessionConfig *session_config;
 940     Session *session = NULL;
 941
 942     l_debug (seat, "Creating user session");
 943
 944     /* Load user preferences */
 945     user = accounts_get_user_by_name (username);
 946     if (!user)
 947     {
 948         l_debug (seat, "Can't login unknown user '%s'", username);
 949         return NULL;
 950     }
 951     session_name = user_get_xsession (user);
 952     language = user_get_language (user);
 953
 954     if (!session_name)
 955         session_name = seat_get_string_property (seat, "user-session");
 956     sessions_dir = config_get_string (config_get_instance (), "LightDM", "sessions-directory");
 957     session_config = find_session_config (seat, sessions_dir, session_name);
 958     g_free (sessions_dir);
 959     if (session_config)
 960     {
 961         gchar **argv;
 962
 963         session = create_session (seat, autostart);
 964         configure_session (session, session_config, session_name, language);
 965         session_set_username (session, username);
 966         session_set_do_authenticate (session, TRUE);
 967         argv = get_session_argv (seat, session_config, seat_get_string_property (seat, "session-wrapper"));
 968         session_set_argv (session, argv);
 969         g_strfreev (argv);
 970         g_object_unref (session_config);
 971     }
 972     else
 973         l_debug (seat, "Can't find session '%s'", session_name);
 974
 975     g_object_unref (user);
 976
 977     return session;
 978 }
 979
 980 static void
 981 prepend_argv (gchar ***argv, const gchar *value)
 982 {
 983     gchar **old_argv, **new_argv;
 984     gint i;
 985
 986     old_argv = *argv;
 987     new_argv = g_malloc (sizeof (gchar *) * (g_strv_length (*argv) + 2));
 988     new_argv[0] = g_strdup (value);
 989     for (i = 0; old_argv[i]; i++)
 990         new_argv[i + 1] = old_argv[i];
 991     new_argv[i + 1] = NULL;
 992
 993     g_free (*argv);
 994     *argv = new_argv;
 995 }
 996
 997 static Session *
 998 create_guest_session (Seat *seat, const gchar *session_name)
 999 {
1000     const gchar *guest_wrapper;
1001     gchar *sessions_dir, **argv;
1002     SessionConfig *session_config;
1003     Session *session;
1004
1005     if (!session_name)
1006         session_name = seat_get_string_property (seat, "guest-session");
1007     if (!session_name)
1008         session_name = seat_get_string_property (seat, "user-session");
1009     sessions_dir = config_get_string (config_get_instance (), "LightDM", "sessions-directory");
1010     session_config = find_session_config (seat, sessions_dir, session_name);
1011     g_free (sessions_dir);
1012     if (!session_config)
1013     {
1014         l_debug (seat, "Can't find session '%s'", session_name);
1015         return NULL;
1016     }
1017
1018     session = create_session (seat, TRUE);
1019     configure_session (session, session_config, session_name, NULL);
1020     session_set_do_authenticate (session, TRUE);
1021     session_set_is_guest (session, TRUE);
1022     argv = get_session_argv (seat, session_config, seat_get_string_property (seat, "session-wrapper"));
1023     guest_wrapper = seat_get_string_property (seat, "guest-wrapper");
1024     if (guest_wrapper)
1025     {
1026         gchar *path;
1027         path = g_find_program_in_path (guest_wrapper);
1028         prepend_argv (&argv, path ? path : guest_wrapper);
1029         g_free (path);
1030     }
1031
1032     session_set_argv (session, argv);
1033     g_strfreev (argv);
1034     g_object_unref (session_config);
1035
1036     return session;
1037 }
1038
1039 static Session *
1040 greeter_create_session_cb (Greeter *greeter, Seat *seat)
1041 {
1042     Session *session;
1043
1044     session = create_session (seat, FALSE);
1045     session_set_session_type (session, session_get_session_type (SESSION (greeter)));
1046     session_set_display_server (session, session_get_display_server (SESSION (greeter)));
1047
1048     return g_object_ref (session);
1049 }
1050
1051 static gboolean
1052 greeter_start_session_cb (Greeter *greeter, SessionType type, const gchar *session_name, Seat *seat)
1053 {
1054     Session *session, *existing_session;
1055     const gchar *username;
1056     DisplayServer *display_server;
1057
1058     /* Get the session to use */
1059     if (greeter_get_guest_authenticated (greeter))
1060     {
1061         session = create_guest_session (seat, session_name);
1062         if (!session)
1063             return FALSE;
1064         session_set_pam_service (session, AUTOLOGIN_SERVICE);
1065     }
1066     else
1067     {
1068         const gchar *language = NULL;
1069         SessionConfig *session_config;
1070         User *user;
1071         gchar *sessions_dir = NULL;
1072         gchar **argv;
1073
1074         session = greeter_get_authentication_session (greeter);
1075
1076         /* Get session command to run */
1077         switch (type)
1078         {
1079         case SESSION_TYPE_LOCAL:
1080             sessions_dir = config_get_string (config_get_instance (), "LightDM", "sessions-directory");
1081             break;
1082         case SESSION_TYPE_REMOTE:
1083             sessions_dir = config_get_string (config_get_instance (), "LightDM", "remote-sessions-directory");
1084             break;
1085         }
1086
1087         /* Load user preferences */
1088         user = session_get_user (session);
1089         if (user)
1090         {
1091             if (!session_name)
1092                 session_name = user_get_xsession (user);
1093             language = user_get_language (user);
1094         }
1095
1096         if (!session_name)
1097             session_name = seat_get_string_property (seat, "user-session");
1098         if (user)
1099             user_set_xsession (session_get_user (session), session_name);
1100
1101         session_config = find_session_config (seat, sessions_dir, session_name);
1102         g_free (sessions_dir);
1103         if (!session_config)
1104         {
1105             l_debug (seat, "Can't find session '%s'", session_name);
1106             return FALSE;
1107         }
1108
1109         configure_session (session, session_config, session_name, language);
1110         argv = get_session_argv (seat, session_config, seat_get_string_property (seat, "session-wrapper"));
1111         session_set_argv (session, argv);
1112         g_strfreev (argv);
1113         g_object_unref (session_config);
1114     }
1115
1116     /* Switch to this session when it is ready */
1117     if (seat->priv->session_to_activate)
1118         g_object_unref (seat->priv->session_to_activate);
1119     seat->priv->session_to_activate = g_object_ref (session);
1120
1121     /* Return to existing session if it is open */
1122     username = session_get_username (session);
1123     existing_session = find_user_session (seat, username, NULL);
1124     if (existing_session && session != existing_session)
1125     {
1126         l_debug (seat, "Returning to existing user session %s", username);
1127         session_stop (session);
1128         session_unlock (existing_session);
1129         seat_set_active_session (seat, existing_session);
1130         return TRUE;
1131     }
1132
1133     /* If can re-use the display server, stop the greeter first */
1134     display_server = session_get_display_server (SESSION (greeter));
1135     if (can_share_display_server (seat, display_server) &&
1136         strcmp (display_server_get_session_type (display_server), session_get_session_type (session)) == 0)
1137     {
1138         l_debug (seat, "Stopping greeter; display server will be re-used for user session");
1139
1140         /* Run on the same display server after the greeter has stopped */
1141         session_set_display_server (session, display_server);
1142
1143         /* Stop the greeter */
1144         session_stop (SESSION (greeter));
1145
1146         return TRUE;
1147     }
1148     /* Otherwise start a new display server for this session */
1149     else
1150     {
1151         display_server = create_display_server (seat, session_get_session_type (session));
1152         session_set_display_server (session, display_server);
1153         if (!display_server_start (display_server))
1154         {
1155             l_debug (seat, "Failed to start display server for new session");
1156             return FALSE;
1157         }
1158
1159         return TRUE;
1160     }
1161 }
1162
1163 static Greeter *
1164 create_greeter_session (Seat *seat)
1165 {
1166     gchar *sessions_dir, **argv;
1167     SessionConfig *session_config;
1168     Greeter *greeter_session;
1169     const gchar *greeter_wrapper;
1170
1171     l_debug (seat, "Creating greeter session");
1172
1173     sessions_dir = config_get_string (config_get_instance (), "LightDM", "greeters-directory");
1174     session_config = find_session_config (seat, sessions_dir, seat_get_string_property (seat, "greeter-session"));
1175     g_free (sessions_dir);
1176     if (!session_config)
1177         return NULL;
1178
1179     argv = get_session_argv (seat, session_config, NULL);
1180     greeter_wrapper = seat_get_string_property (seat, "greeter-wrapper");
1181     if (greeter_wrapper)
1182     {
1183         gchar *path;
1184         path = g_find_program_in_path (greeter_wrapper);
1185         prepend_argv (&argv, path ? path : greeter_wrapper);
1186         g_free (path);
1187     }
1188
1189     greeter_session = SEAT_GET_CLASS (seat)->create_greeter_session (seat);
1190     session_set_session_type (SESSION (greeter_session), session_config_get_session_type (session_config));
1191     seat->priv->sessions = g_list_append (seat->priv->sessions, SESSION (greeter_session));
1192     g_signal_connect (greeter_session, "notify::active-username", G_CALLBACK (greeter_active_username_changed_cb), seat);
1193     g_signal_connect (greeter_session, "authentication-complete", G_CALLBACK (session_authentication_complete_cb), seat);
1194     g_signal_connect (greeter_session, "stopped", G_CALLBACK (session_stopped_cb), seat);
1195
1196     set_session_env (SESSION (greeter_session));
1197     session_set_env (SESSION (greeter_session), "XDG_SESSION_CLASS", "greeter");
1198
1199     session_set_pam_service (SESSION (greeter_session), GREETER_SERVICE);
1200     if (getuid () == 0)
1201     {
1202         gchar *greeter_user;
1203         greeter_user = config_get_string (config_get_instance (), "LightDM", "greeter-user");
1204         session_set_username (SESSION (greeter_session), greeter_user);
1205         g_free (greeter_user);
1206     }
1207     else
1208     {
1209         /* In test mode run the greeter as ourself */
1210         session_set_username (SESSION (greeter_session), user_get_name (accounts_get_current_user ()));
1211     }
1212     session_set_argv (SESSION (greeter_session), argv);
1213     g_strfreev (argv);
1214
1215     greeter_set_pam_services (greeter_session, USER_SERVICE, AUTOLOGIN_SERVICE);
1216     g_signal_connect (greeter_session, "create-session", G_CALLBACK (greeter_create_session_cb), seat);
1217     g_signal_connect (greeter_session, "start-session", G_CALLBACK (greeter_start_session_cb), seat);
1218
1219     /* Set hints to greeter */
1220     greeter_set_allow_guest (greeter_session, seat_get_allow_guest (seat));
1221     reset_greeter_hints (seat, greeter_session);
1222
1223     g_object_unref (session_config);
1224
1225     return greeter_session;
1226 }
1227
1228 static Session *
1229 find_session_for_display_server (Seat *seat, DisplayServer *display_server)
1230 {
1231     GList *link;
1232
1233     for (link = seat->priv->sessions; link; link = link->next)
1234     {
1235         Session *session = link->data;
1236         if (session_get_display_server (session) == display_server && !session_get_is_stopping (session))
1237             return session;
1238     }
1239
1240     return NULL;
1241 }
1242
1243 static void
1244 display_server_ready_cb (DisplayServer *display_server, Seat *seat)
1245 {
1246     const gchar *script;
1247     Session *session;
1248
1249     /* Run setup script */
1250     script = seat_get_string_property (seat, "display-setup-script");
1251     if (script && !run_script (seat, display_server, script, NULL))
1252     {
1253         l_debug (seat, "Stopping display server due to failed setup script");
1254         display_server_stop (display_server);
1255         return;
1256     }
1257
1258     /* Stop if don't need to run a session */
1259     if (!get_start_local_sessions (seat))
1260         return;
1261
1262     emit_upstart_signal ("login-session-start");
1263
1264     /* Start the session waiting for this display server */
1265     session = find_session_for_display_server (seat, display_server);
1266     if (session)
1267     {
1268         if (session_get_is_authenticated (session))
1269         {
1270             l_debug (seat, "Display server ready, running session");
1271             run_session (seat, session);
1272         }
1273         else
1274         {
1275             l_debug (seat, "Display server ready, starting session authentication");
1276             start_session (seat, session);
1277         }
1278     }
1279     else
1280     {
1281         l_debug (seat, "Stopping not required display server");
1282         display_server_stop (display_server);
1283     }
1284 }
1285
1286 static DisplayServer *
1287 create_display_server (Seat *seat, const gchar *session_type)
1288 {
1289     DisplayServer *display_server;
1290
1291     l_debug (seat, "Creating display server of type %s", session_type);
1292
1293     display_server = SEAT_GET_CLASS (seat)->create_display_server (seat, session_type);
1294     if (!display_server)
1295         return NULL;
1296
1297     seat->priv->display_servers = g_list_append (seat->priv->display_servers, display_server);
1298     g_signal_connect (display_server, "ready", G_CALLBACK (display_server_ready_cb), seat);
1299     g_signal_connect (display_server, "stopped", G_CALLBACK (display_server_stopped_cb), seat);
1300
1301     return display_server;
1302 }
1303
1304 gboolean
1305 seat_switch_to_greeter (Seat *seat)
1306 {
1307     Greeter *greeter_session;
1308     DisplayServer *display_server;
1309
1310     g_return_val_if_fail (seat != NULL, FALSE);
1311
1312     if (!seat->priv->can_switch)
1313         return FALSE;
1314
1315     /* Switch to greeter if one open */
1316     greeter_session = find_greeter_session (seat);
1317     if (greeter_session)
1318     {
1319         l_debug (seat, "Switching to existing greeter");
1320         seat_set_active_session (seat, SESSION (greeter_session));
1321         return TRUE;
1322     }
1323
1324     greeter_session = create_greeter_session (seat);
1325     if (!greeter_session)
1326         return FALSE;
1327
1328     if (seat->priv->session_to_activate)
1329         g_object_unref (seat->priv->session_to_activate);
1330     seat->priv->session_to_activate = g_object_ref (greeter_session);
1331
1332     display_server = create_display_server (seat, session_get_session_type (SESSION (greeter_session)));
1333     session_set_display_server (SESSION (greeter_session), display_server);
1334     if (!display_server_start (display_server))
1335         return FALSE;
1336
1337     return TRUE;
1338 }
1339
1340 static void
1341 switch_authentication_complete_cb (Session *session, Seat *seat)
1342 {
1343     Greeter *greeter_session;
1344     DisplayServer *display_server;
1345     gboolean existing = FALSE;
1346
1347     /* If authenticated, then unlock existing session or start new one */
1348     if (session_get_is_authenticated (session))
1349     {
1350         Session *s;
1351
1352         s = find_user_session (seat, session_get_username (session), session);
1353         if (s)
1354         {
1355             l_debug (seat, "Session authenticated, switching to existing user session");
1356             session_unlock (s);
1357             seat_set_active_session (seat, s);
1358             session_stop (session);
1359         }
1360         else
1361         {
1362             l_debug (seat, "Session authenticated, starting display server");
1363             if (seat->priv->session_to_activate)
1364                 g_object_unref (seat->priv->session_to_activate);
1365             seat->priv->session_to_activate = g_object_ref (session);
1366             display_server = create_display_server (seat, session_get_session_type (session));
1367             session_set_display_server (session, display_server);
1368             display_server_start (display_server);
1369         }
1370
1371         return;
1372     }
1373
1374     session_stop (session);
1375
1376     /* See if we already have a greeter up and reuse it if so.  Which will only
1377        happen if the greeter marked itself as resettable and we thus didn't
1378        kill it when a user session started */
1379     greeter_session = find_greeter_session (seat);
1380     if (greeter_session)
1381     {
1382         l_debug (seat, "Switching to existing greeter to authenticate session");
1383         reset_greeter_hints (seat, greeter_session);
1384         existing = TRUE;
1385     }
1386     else
1387     {
1388         l_debug (seat, "Starting greeter to authenticate session");
1389         greeter_session = create_greeter_session (seat);
1390     }
1391
1392     if (session_get_is_guest (session))
1393         greeter_set_hint (greeter_session, "select-guest", "true");
1394     else
1395         greeter_set_hint (greeter_session, "select-user", session_get_username (session));
1396
1397     if (existing)
1398     {
1399         greeter_reset (greeter_session);
1400         seat_set_active_session (seat, SESSION (greeter_session));
1401     }
1402     else
1403     {
1404         if (seat->priv->session_to_activate)
1405             g_object_unref (seat->priv->session_to_activate);
1406         seat->priv->session_to_activate = g_object_ref (greeter_session);
1407
1408         display_server = create_display_server (seat, session_get_session_type (SESSION (greeter_session)));
1409         session_set_display_server (SESSION (greeter_session), display_server);
1410         display_server_start (display_server);
1411     }
1412 }
1413
1414 gboolean
1415 seat_switch_to_user (Seat *seat, const gchar *username, const gchar *session_name)
1416 {
1417     Session *session;
1418
1419     g_return_val_if_fail (seat != NULL, FALSE);
1420     g_return_val_if_fail (username != NULL, FALSE);
1421
1422     if (!seat->priv->can_switch)
1423         return FALSE;
1424
1425     /* If we're already on this session, then ignore */
1426     session = find_user_session (seat, username, NULL);
1427     if (session && session == seat->priv->active_session)
1428         return TRUE;
1429
1430     l_debug (seat, "Switching to user %s", username);
1431
1432     /* Attempt to authenticate them */
1433     session = create_user_session (seat, username, FALSE);
1434     g_signal_connect (session, "authentication-complete", G_CALLBACK (switch_authentication_complete_cb), seat);
1435     session_set_pam_service (session, USER_SERVICE);
1436     session_start (session);
1437
1438     return FALSE;
1439 }
1440
1441 static Session *
1442 find_guest_session (Seat *seat)
1443 {
1444     GList *link;
1445
1446     for (link = seat->priv->sessions; link; link = link->next)
1447     {
1448         Session *session = link->data;
1449         if (!session_get_is_stopping (session) && session_get_is_guest (session))
1450             return session;
1451     }
1452
1453     return NULL;
1454 }
1455
1456 gboolean
1457 seat_switch_to_guest (Seat *seat, const gchar *session_name)
1458 {
1459     Session *session;
1460     DisplayServer *display_server;
1461
1462     g_return_val_if_fail (seat != NULL, FALSE);
1463
1464     if (!seat->priv->can_switch || !seat_get_allow_guest (seat))
1465         return FALSE;
1466
1467     /* Switch to session if one open */
1468     session = find_guest_session (seat);
1469     if (session)
1470     {
1471         l_debug (seat, "Switching to existing guest account %s", session_get_username (session));
1472         seat_set_active_session (seat, session);
1473         return TRUE;
1474     }
1475
1476     session = create_guest_session (seat, session_name);
1477     if (!session)
1478         return FALSE;
1479
1480     display_server = create_display_server (seat, session_get_session_type (session));
1481
1482     if (seat->priv->session_to_activate)
1483         g_object_unref (seat->priv->session_to_activate);
1484     seat->priv->session_to_activate = g_object_ref (session);
1485     session_set_pam_service (session, AUTOLOGIN_SERVICE);
1486     session_set_display_server (session, display_server);
1487
1488     return display_server_start (display_server);
1489 }
1490
1491 gboolean
1492 seat_lock (Seat *seat, const gchar *username)
1493 {
1494     Greeter *greeter_session;
1495     DisplayServer *display_server;
1496     gboolean existing = FALSE;
1497
1498     g_return_val_if_fail (seat != NULL, FALSE);
1499
1500     if (!seat->priv->can_switch)
1501         return FALSE;
1502
1503     l_debug (seat, "Locking");
1504
1505     /* Switch to greeter if one open (only true if it's a resettable greeter) */
1506     greeter_session = find_greeter_session (seat);
1507     if (greeter_session)
1508     {
1509         l_debug (seat, "Switching to existing greeter");
1510         reset_greeter_hints (seat, greeter_session);
1511         existing = TRUE;
1512     }
1513     else
1514     {
1515         greeter_session = create_greeter_session (seat);
1516         if (!greeter_session)
1517             return FALSE;
1518     }
1519
1520     greeter_set_hint (greeter_session, "lock-screen", "true");
1521     if (username)
1522         greeter_set_hint (greeter_session, "select-user", username);
1523
1524     if (existing)
1525     {
1526         greeter_reset (greeter_session);
1527         seat_set_active_session (seat, SESSION (greeter_session));
1528         return TRUE;
1529     }
1530     else
1531     {
1532         display_server = create_display_server (seat, session_get_session_type (SESSION (greeter_session)));
1533
1534         if (seat->priv->session_to_activate)
1535             g_object_unref (seat->priv->session_to_activate);
1536         seat->priv->session_to_activate = g_object_ref (greeter_session);
1537         session_set_display_server (SESSION (greeter_session), display_server);
1538
1539         return display_server_start (display_server);
1540     }
1541 }
1542
1543 void
1544 seat_stop (Seat *seat)
1545 {
1546     g_return_if_fail (seat != NULL);
1547
1548     if (seat->priv->stopping)
1549         return;
1550
1551     l_debug (seat, "Stopping");
1552     seat->priv->stopping = TRUE;
1553     SEAT_GET_CLASS (seat)->stop (seat);
1554 }
1555
1556 gboolean
1557 seat_get_is_stopping (Seat *seat)
1558 {
1559     g_return_val_if_fail (seat != NULL, FALSE);
1560     return seat->priv->stopping;
1561 }
1562
1563 static gboolean
1564 seat_real_get_start_local_sessions (Seat *seat)
1565 {
1566     return TRUE;
1567 }
1568
1569 static void
1570 seat_real_setup (Seat *seat)
1571 {
1572 }
1573
1574 static gboolean
1575 seat_real_start (Seat *seat)
1576 {
1577     const gchar *autologin_username;
1578     int autologin_timeout;
1579     gboolean autologin_guest;
1580     gboolean autologin_in_background;
1581     Session *session = NULL, *background_session = NULL;
1582
1583     l_debug (seat, "Starting");
1584
1585     /* If this display server doesn't have a session running on it, just start it */
1586     if (!get_start_local_sessions (seat))
1587     {
1588         DisplayServer *display_server;
1589         display_server = create_display_server (seat, "x"); // FIXME: Not necessarily an X seat, but not sure what to put here
1590         return display_server_start (display_server);
1591     }
1592
1593     /* Get autologin settings */
1594     autologin_username = seat_get_string_property (seat, "autologin-user");
1595     if (g_strcmp0 (autologin_username, "") == 0)
1596         autologin_username = NULL;
1597     autologin_timeout = seat_get_integer_property (seat, "autologin-user-timeout");
1598     autologin_guest = seat_get_boolean_property (seat, "autologin-guest");
1599     autologin_in_background = seat_get_boolean_property (seat, "autologin-in-background");
1600
1601     /* Autologin if configured */
1602     if (autologin_timeout == 0 || autologin_in_background)
1603     {
1604         if (autologin_guest)
1605             session = create_guest_session (seat, NULL);
1606         else if (autologin_username != NULL)
1607             session = create_user_session (seat, autologin_username, TRUE);
1608
1609         if (session)
1610             session_set_pam_service (session, AUTOLOGIN_SERVICE);
1611
1612         /* Load in background if required */
1613         if (autologin_in_background && session)
1614         {
1615             background_session = session;
1616             session = NULL;
1617         }
1618
1619         if (session)
1620         {
1621             DisplayServer *display_server;
1622
1623             if (seat->priv->session_to_activate)
1624                 g_object_unref (seat->priv->session_to_activate);
1625             seat->priv->session_to_activate = g_object_ref (session);
1626
1627             display_server = create_display_server (seat, session_get_session_type (session));
1628             session_set_display_server (session, display_server);
1629             if (!display_server || !display_server_start (display_server))
1630             {
1631                 l_debug (seat, "Can't create display server for automatic login");
1632                 session_stop (session);
1633                 if (display_server)
1634                     display_server_stop (display_server);
1635                 session = NULL;
1636             }
1637         }
1638     }
1639
1640     /* Fallback to a greeter */
1641     if (!session)
1642     {
1643         Greeter *greeter_session;
1644         DisplayServer *display_server;
1645
1646         greeter_session = create_greeter_session (seat);
1647         if (!greeter_session)
1648         {
1649             l_debug (seat, "Failed to create greeter session");
1650             return FALSE;
1651         }
1652
1653         if (seat->priv->session_to_activate)
1654             g_object_unref (seat->priv->session_to_activate);
1655         seat->priv->session_to_activate = g_object_ref (greeter_session);
1656         session = SESSION (greeter_session);
1657
1658         if (autologin_timeout)
1659         {
1660             gchar *value;
1661
1662             value = g_strdup_printf ("%d", autologin_timeout);
1663             greeter_set_hint (greeter_session, "autologin-timeout", value);
1664             g_free (value);
1665             if (autologin_username)
1666                 greeter_set_hint (greeter_session, "autologin-user", autologin_username);
1667             if (autologin_guest)
1668                 greeter_set_hint (greeter_session, "autologin-guest", "true");
1669         }
1670
1671         display_server = create_display_server (seat, session_get_session_type (session));
1672         session_set_display_server (session, display_server);
1673         if (!display_server || !display_server_start (display_server))
1674         {
1675             l_debug (seat, "Can't create display server for greeter");
1676             session_stop (session);
1677             if (display_server)
1678                 display_server_stop (display_server);
1679             session = NULL;
1680         }
1681     }
1682
1683     /* Fail if can't start a session */
1684     if (!session)
1685     {
1686         seat_stop (seat);
1687         return FALSE;
1688     }
1689
1690     /* Start background session */
1691     if (background_session)
1692     {
1693         DisplayServer *background_display_server;
1694
1695         background_display_server = create_display_server (seat, session_get_session_type (background_session));
1696         session_set_display_server (background_session, background_display_server);
1697         if (!display_server_start (background_display_server))
1698             l_warning (seat, "Failed to start display server for background session");
1699     }
1700
1701     seat->priv->started = TRUE;
1702     return TRUE;
1703 }
1704
1705 static Greeter *
1706 seat_real_create_greeter_session (Seat *seat)
1707 {
1708     return greeter_new ();
1709 }
1710
1711 static Session *
1712 seat_real_create_session (Seat *seat)
1713 {
1714     return session_new ();
1715 }
1716
1717 static void
1718 seat_real_set_active_session (Seat *seat, Session *session)
1719 {
1720 }
1721
1722 static void
1723 seat_real_set_next_session (Seat *seat, Session *session)
1724 {
1725 }
1726
1727 static Session *
1728 seat_real_get_active_session (Seat *seat)
1729 {
1730     return NULL;
1731 }
1732
1733 static void
1734 seat_real_stop (Seat *seat)
1735 {
1736     GList *list, *link;
1737
1738     check_stopped (seat);
1739     if (seat->priv->stopped)
1740         return;
1741
1742     /* Stop all the display servers and sessions on the seat. Copy the list as
1743      * it might be modified if a display server / session stops during this loop */
1744     list = g_list_copy (seat->priv->display_servers);
1745     for (link = list; link; link = link->next)
1746         g_object_ref (link->data);
1747     for (link = list; link; link = link->next)
1748     {
1749         DisplayServer *display_server = link->data;
1750         if (!display_server_get_is_stopping (display_server))
1751         {
1752             l_debug (seat, "Stopping display server");
1753             display_server_stop (display_server);
1754         }
1755     }
1756     g_list_free_full (list, g_object_unref);
1757     list = g_list_copy (seat->priv->sessions);
1758     for (link = list; link; link = link->next)
1759         g_object_ref (link->data);
1760     for (link = list; link; link = link->next)
1761     {
1762         Session *session = link->data;
1763         if (!session_get_is_stopping (session))
1764         {
1765             l_debug (seat, "Stopping session");
1766             session_stop (session);
1767         }
1768     }
1769     g_list_free_full (list, g_object_unref);
1770 }
1771
1772 static void
1773 seat_init (Seat *seat)
1774 {
1775     seat->priv = G_TYPE_INSTANCE_GET_PRIVATE (seat, SEAT_TYPE, SeatPrivate);
1776     seat->priv->properties = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, g_free);
1777     seat->priv->share_display_server = TRUE;
1778 }
1779
1780 static void
1781 seat_finalize (GObject *object)
1782 {
1783     Seat *self;
1784     GList *link;
1785
1786     self = SEAT (object);
1787
1788     g_hash_table_unref (self->priv->properties);
1789     for (link = self->priv->display_servers; link; link = link->next)
1790     {
1791         DisplayServer *display_server = link->data;
1792         g_signal_handlers_disconnect_matched (display_server, G_SIGNAL_MATCH_DATA, 0, 0, NULL, NULL, self);
1793     }
1794     g_list_free_full (self->priv->display_servers, g_object_unref);
1795     for (link = self->priv->sessions; link; link = link->next)
1796     {
1797         Session *session = link->data;
1798         g_signal_handlers_disconnect_matched (session, G_SIGNAL_MATCH_DATA, 0, 0, NULL, NULL, self);
1799     }
1800     g_list_free_full (self->priv->sessions, g_object_unref);
1801     if (self->priv->active_session)
1802         g_object_unref (self->priv->active_session);
1803     if (self->priv->next_session)
1804         g_object_unref (self->priv->next_session);
1805     if (self->priv->session_to_activate)
1806         g_object_unref (self->priv->session_to_activate);
1807
1808     G_OBJECT_CLASS (seat_parent_class)->finalize (object);
1809 }
1810
1811 static void
1812 seat_class_init (SeatClass *klass)
1813 {
1814     GObjectClass *object_class = G_OBJECT_CLASS (klass);
1815
1816     klass->get_start_local_sessions = seat_real_get_start_local_sessions;
1817     klass->setup = seat_real_setup;
1818     klass->start = seat_real_start;
1819     klass->create_greeter_session = seat_real_create_greeter_session;
1820     klass->create_session = seat_real_create_session;
1821     klass->set_active_session = seat_real_set_active_session;
1822     klass->get_active_session = seat_real_get_active_session;
1823     klass->set_next_session = seat_real_set_next_session;
1824     klass->run_script = seat_real_run_script;
1825     klass->stop = seat_real_stop;
1826
1827     object_class->finalize = seat_finalize;
1828
1829     g_type_class_add_private (klass, sizeof (SeatPrivate));
1830
1831     signals[SESSION_ADDED] =
1832         g_signal_new ("session-added",
1833                       G_TYPE_FROM_CLASS (klass),
1834                       G_SIGNAL_RUN_LAST,
1835                       G_STRUCT_OFFSET (SeatClass, session_added),
1836                       NULL, NULL,
1837                       NULL,
1838                       G_TYPE_NONE, 1, SESSION_TYPE);
1839     signals[RUNNING_USER_SESSION] =
1840         g_signal_new ("running-user-session",
1841                       G_TYPE_FROM_CLASS (klass),
1842                       G_SIGNAL_RUN_LAST,
1843                       G_STRUCT_OFFSET (SeatClass, running_user_session),
1844                       NULL, NULL,
1845                       NULL,
1846                       G_TYPE_NONE, 1, SESSION_TYPE);
1847     signals[SESSION_REMOVED] =
1848         g_signal_new ("session-removed",
1849                       G_TYPE_FROM_CLASS (klass),
1850                       G_SIGNAL_RUN_LAST,
1851                       G_STRUCT_OFFSET (SeatClass, session_removed),
1852                       NULL, NULL,
1853                       NULL,
1854                       G_TYPE_NONE, 1, SESSION_TYPE);
1855     signals[STOPPED] =
1856         g_signal_new ("stopped",
1857                       G_TYPE_FROM_CLASS (klass),
1858                       G_SIGNAL_RUN_LAST,
1859                       G_STRUCT_OFFSET (SeatClass, stopped),
1860                       NULL, NULL,
1861                       NULL,
1862                       G_TYPE_NONE, 0);
1863 }
1864
1865 static gint
1866 seat_real_logprefix (Logger *self, gchar *buf, gulong buflen)
1867 {
1868     Seat *seat = SEAT (self);
1869     const gchar *name = seat_get_string_property (seat, "seat-name");
1870     if (name)
1871         return g_snprintf (buf, buflen, "Seat %s: ", name);
1872     else
1873         return g_snprintf (buf, buflen, "Seat: ");
1874 }
1875
1876 static void
1877 seat_logger_iface_init (LoggerInterface *iface)
1878 {
1879     iface->logprefix = &seat_real_logprefix;
1880 }