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