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