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 this seat can run multiple sessions at once */
  37     gboolean supports_multi_session;
  38
  39     /* TRUE if display server can be shared for sessions */
  40     gboolean share_display_server;
  41
  42     /* The display servers on this seat */
  43     GList *display_servers;
  44
  45     /* The sessions on this seat */
  46     GList *sessions;
  47
  48     /* The last session set to active */
  49     Session *active_session;
  50
  51     /* The session belonging to the active greeter user */
  52     Session *next_session;
  53
  54     /* The session to set active when it starts */
  55     Session *session_to_activate;
  56
  57     /* TRUE once we have started */
  58     gboolean started;
  59
  60     /* TRUE if stopping this seat (waiting for displays to stop) */
  61     gboolean stopping;
  62
  63     /* TRUE if stopped */
  64     gboolean stopped;
  65 };
  66
  67 static void seat_logger_iface_init (LoggerInterface *iface);
  68
  69 G_DEFINE_TYPE_WITH_CODE (Seat, seat, G_TYPE_OBJECT,
  70                          G_IMPLEMENT_INTERFACE (
  71                              LOGGER_TYPE, seat_logger_iface_init));
  72
  73 typedef struct
  74 {
  75     const gchar *name;
  76     GType type;
  77 } SeatModule;
  78 static GHashTable *seat_modules = NULL;
  79
  80 // FIXME: Make a get_display_server() that re-uses display servers if supported
  81 static DisplayServer *create_display_server (Seat *seat, Session *session);
  82 static Greeter *create_greeter_session (Seat *seat);
  83 static void start_session (Seat *seat, Session *session);
  84
  85 void
  86 seat_register_module (const gchar *name, GType type)
  87 {
  88     SeatModule *module;
  89
  90     if (!seat_modules)
  91         seat_modules = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, NULL);
  92
  93     g_debug ("Registered seat module %s", name);
  94
  95     module = g_malloc0 (sizeof (SeatModule));
  96     module->name = g_strdup (name);
  97     module->type = type;
  98     g_hash_table_insert (seat_modules, g_strdup (name), module);
  99 }
 100
 101 Seat *
 102 seat_new (const gchar *module_name)
 103 {
 104     Seat *seat;
 105     SeatModule *m = NULL;
 106
 107     g_return_val_if_fail (module_name != NULL, NULL);
 108
 109     if (seat_modules)
 110         m = g_hash_table_lookup (seat_modules, module_name);
 111     if (!m)
 112         return NULL;
 113
 114     seat = g_object_new (m->type, NULL);
 115
 116     return seat;
 117 }
 118
 119 void
 120 seat_set_property (Seat *seat, const gchar *name, const gchar *value)
 121 {
 122     g_return_if_fail (seat != NULL);
 123     g_hash_table_insert (seat->priv->properties, g_strdup (name), g_strdup (value));
 124 }
 125
 126 const gchar *
 127 seat_get_string_property (Seat *seat, const gchar *name)
 128 {
 129     g_return_val_if_fail (seat != NULL, NULL);
 130     return g_hash_table_lookup (seat->priv->properties, name);
 131 }
 132
 133 gchar **
 134 seat_get_string_list_property (Seat *seat, const gchar *name)
 135 {
 136     g_return_val_if_fail (seat != NULL, NULL);
 137     return g_strsplit (g_hash_table_lookup (seat->priv->properties, name), ";", 0);
 138 }
 139
 140 gboolean
 141 seat_get_boolean_property (Seat *seat, const gchar *name)
 142 {
 143     return g_strcmp0 (seat_get_string_property (seat, name), "true") == 0;
 144 }
 145
 146 gint
 147 seat_get_integer_property (Seat *seat, const gchar *name)
 148 {
 149     const gchar *value;
 150
 151     value = seat_get_string_property (seat, name);
 152     return value ? atoi (value) : 0;
 153 }
 154
 155 const gchar *
 156 seat_get_name (Seat *seat)
 157 {
 158     const gchar *name;
 159
 160     name = seat_get_string_property (seat, "xdg-seat");
 161     if (name)
 162         return name;
 163
 164     return "seat0";
 165 }
 166
 167 void
 168 seat_set_supports_multi_session (Seat *seat, gboolean supports_multi_session)
 169 {
 170     g_return_if_fail (seat != NULL);
 171     seat->priv->supports_multi_session = supports_multi_session;
 172 }
 173
 174 void
 175 seat_set_share_display_server (Seat *seat, gboolean share_display_server)
 176 {
 177     g_return_if_fail (seat != NULL);
 178     seat->priv->share_display_server = share_display_server;
 179 }
 180
 181 gboolean
 182 seat_start (Seat *seat)
 183 {
 184     g_return_val_if_fail (seat != NULL, FALSE);
 185
 186     l_debug (seat, "Starting");
 187
 188     SEAT_GET_CLASS (seat)->setup (seat);
 189     seat->priv->started = SEAT_GET_CLASS (seat)->start (seat);
 190
 191     return seat->priv->started;
 192 }
 193
 194 GList *
 195 seat_get_sessions (Seat *seat)
 196 {
 197     g_return_val_if_fail (seat != NULL, NULL);
 198     return seat->priv->sessions;
 199 }
 200
 201 static gboolean
 202 set_greeter_idle (gpointer greeter)
 203 {
 204     greeter_idle (GREETER (greeter));
 205     return FALSE;
 206 }
 207
 208 void
 209 seat_set_active_session (Seat *seat, Session *session)
 210 {
 211     GList *link;
 212
 213     g_return_if_fail (seat != NULL);
 214
 215     SEAT_GET_CLASS (seat)->set_active_session (seat, session);
 216
 217     /* Stop any greeters */
 218     for (link = seat->priv->sessions; link; link = link->next)
 219     {
 220         Session *s = link->data;
 221
 222         if (s == session || session_get_is_stopping (s))
 223             continue;
 224
 225         if (IS_GREETER (s))
 226         {
 227             Greeter *greeter = GREETER (s);
 228             if (greeter_get_resettable (greeter))
 229             {
 230                 if (seat->priv->active_session == SESSION (greeter))
 231                 {
 232                     l_debug (seat, "Idling greeter");
 233                     /* Do this in an idle callback, because we might very well
 234                        be in the middle of responding to a START_SESSION
 235                        request by a greeter.  So they won't expect an IDLE
 236                        call during that.  Plus, this isn't time-sensitive. */
 237                     g_idle_add (set_greeter_idle, greeter);
 238                 }
 239             }
 240             else
 241             {
 242                 l_debug (seat, "Stopping greeter");
 243                 session_stop (s);
 244             }
 245         }
 246     }
 247
 248     /* Lock previous sessions */
 249     if (seat->priv->active_session)
 250     {
 251         if (session != seat->priv->active_session && !IS_GREETER (seat->priv->active_session))
 252             session_lock (seat->priv->active_session);
 253         g_object_unref (seat->priv->active_session);
 254     }
 255
 256     session_activate (session);
 257     seat->priv->active_session = g_object_ref (session);
 258 }
 259
 260 Session *
 261 seat_get_active_session (Seat *seat)
 262 {
 263     g_return_val_if_fail (seat != NULL, NULL);
 264     return SEAT_GET_CLASS (seat)->get_active_session (seat);
 265 }
 266
 267 Session *
 268 seat_get_next_session (Seat *seat)
 269 {
 270     g_return_val_if_fail (seat != NULL, NULL);
 271     return seat->priv->next_session;
 272 }
 273
 274 gboolean
 275 seat_get_can_switch (Seat *seat)
 276 {
 277     g_return_val_if_fail (seat != NULL, FALSE);
 278     return seat_get_boolean_property (seat, "allow-user-switching") && seat->priv->supports_multi_session;
 279 }
 280
 281 gboolean
 282 seat_get_allow_guest (Seat *seat)
 283 {
 284     g_return_val_if_fail (seat != NULL, FALSE);
 285     return seat_get_boolean_property (seat, "allow-guest") && guest_account_is_installed ();
 286 }
 287
 288 static gboolean
 289 run_script (Seat *seat, DisplayServer *display_server, const gchar *script_name, User *user)
 290 {
 291     Process *script;
 292     gboolean result = FALSE;
 293
 294     script = process_new (NULL, NULL);
 295
 296     process_set_command (script, script_name);
 297
 298     /* Set POSIX variables */
 299     process_set_clear_environment (script, TRUE);
 300     process_set_env (script, "SHELL", "/bin/sh");
 301
 302     /* Variables required for regression tests */
 303     if (g_getenv ("LIGHTDM_TEST_ROOT"))
 304     {
 305         process_set_env (script, "LIGHTDM_TEST_ROOT", g_getenv ("LIGHTDM_TEST_ROOT"));
 306         process_set_env (script, "LD_PRELOAD", g_getenv ("LD_PRELOAD"));
 307         process_set_env (script, "LD_LIBRARY_PATH", g_getenv ("LD_LIBRARY_PATH"));
 308         process_set_env (script, "PATH", g_getenv ("PATH"));
 309     }
 310     else
 311         process_set_env (script, "PATH", "/usr/local/bin:/usr/bin:/bin");
 312
 313     if (user)
 314     {
 315         process_set_env (script, "USER", user_get_name (user));
 316         process_set_env (script, "LOGNAME", user_get_name (user));
 317         process_set_env (script, "HOME", user_get_home_directory (user));
 318     }
 319     else
 320         process_set_env (script, "HOME", "/");
 321
 322     SEAT_GET_CLASS (seat)->run_script (seat, display_server, script);
 323
 324     if (process_start (script, TRUE))
 325     {
 326         int exit_status;
 327
 328         exit_status = process_get_exit_status (script);
 329         if (WIFEXITED (exit_status))
 330         {
 331             l_debug (seat, "Exit status of %s: %d", script_name, WEXITSTATUS (exit_status));
 332             result = WEXITSTATUS (exit_status) == EXIT_SUCCESS;
 333         }
 334     }
 335
 336     g_object_unref (script);
 337
 338     return result;
 339 }
 340
 341 static void
 342 seat_real_run_script (Seat *seat, DisplayServer *display_server, Process *process)
 343 {
 344 }
 345
 346 static void
 347 emit_upstart_signal (const gchar *signal)
 348 {
 349     g_return_if_fail (signal != NULL);
 350     g_return_if_fail (signal[0] != 0);
 351
 352     if (getuid () != 0)
 353         return;
 354
 355     gchar *cmd = g_strdup_printf ("initctl -q emit %s DISPLAY_MANAGER=lightdm", signal);
 356     g_spawn_command_line_async (cmd, NULL); /* OK if it fails, probably not installed */
 357     g_free (cmd);
 358 }
 359
 360 static void
 361 check_stopped (Seat *seat)
 362 {
 363     if (seat->priv->stopping &&
 364         !seat->priv->stopped &&
 365         g_list_length (seat->priv->display_servers) == 0 &&
 366         g_list_length (seat->priv->sessions) == 0)
 367     {
 368         seat->priv->stopped = TRUE;
 369         l_debug (seat, "Stopped");
 370         g_signal_emit (seat, signals[STOPPED], 0);
 371     }
 372 }
 373
 374 static void
 375 display_server_stopped_cb (DisplayServer *display_server, Seat *seat)
 376 {
 377     const gchar *script;
 378     GList *list, *link;
 379     Session *active_session;
 380
 381     l_debug (seat, "Display server stopped");
 382
 383     /* Run a script right after stopping the display server */
 384     script = seat_get_string_property (seat, "display-stopped-script");
 385     if (script)
 386         run_script (seat, NULL, script, NULL);
 387
 388     g_signal_handlers_disconnect_matched (display_server, G_SIGNAL_MATCH_DATA, 0, 0, NULL, NULL, seat);
 389     seat->priv->display_servers = g_list_remove (seat->priv->display_servers, display_server);
 390
 391     if (seat->priv->stopping || !seat->priv->started)
 392     {
 393         check_stopped (seat);
 394         g_object_unref (display_server);
 395         return;
 396     }
 397
 398     /* Stop all sessions on this display server */
 399     list = g_list_copy (seat->priv->sessions);
 400     for (link = list; link; link = link->next)
 401         g_object_ref (link->data);
 402     for (link = list; link; link = link->next)
 403     {
 404         Session *session = link->data;
 405
 406         if (session_get_display_server (session) != display_server || session_get_is_stopping (session))
 407             continue;
 408
 409         /* Stop seat if this is the only display server and it failed to start a greeter */
 410         if (IS_GREETER (session) &&
 411             !session_get_is_started (session) &&
 412             g_list_length (seat->priv->display_servers) == 0)
 413         {
 414             l_debug (seat, "Stopping; greeter display server failed to start");
 415             seat_stop (seat);
 416         }
 417
 418         l_debug (seat, "Stopping session");
 419         session_stop (session);
 420     }
 421     g_list_free_full (list, g_object_unref);
 422
 423     if (!seat->priv->stopping)
 424     {
 425         /* If we were the active session, switch to a greeter */
 426         active_session = seat_get_active_session (seat);
 427         if (!active_session || session_get_display_server (active_session) == display_server)
 428         {
 429             l_debug (seat, "Active display server stopped, starting greeter");
 430             if (!seat_switch_to_greeter (seat))
 431             {
 432                 l_debug (seat, "Stopping; failed to start a greeter");
 433                 seat_stop (seat);
 434             }
 435         }
 436     }
 437
 438     g_object_unref (display_server);
 439 }
 440
 441 static gboolean
 442 can_share_display_server (Seat *seat, DisplayServer *display_server)
 443 {
 444     return seat->priv->share_display_server && display_server_get_can_share (display_server);
 445 }
 446
 447 static Greeter *
 448 find_greeter_session (Seat *seat)
 449 {
 450     GList *link;
 451
 452     for (link = seat->priv->sessions; link; link = link->next)
 453     {
 454         Session *session = link->data;
 455         if (!session_get_is_stopping (session) && IS_GREETER (session))
 456             return GREETER (session);
 457     }
 458
 459     return NULL;
 460 }
 461
 462 static Greeter *
 463 find_resettable_greeter (Seat *seat)
 464 {
 465     GList *link;
 466
 467     for (link = seat->priv->sessions; link; link = link->next)
 468     {
 469         Session *session = link->data;
 470         if (!session_get_is_stopping (session) && IS_GREETER (session) &&
 471             greeter_get_resettable (GREETER (session)))
 472             return GREETER (session);
 473     }
 474
 475     return NULL;
 476 }
 477
 478 static void
 479 set_greeter_hints (Seat *seat, Greeter *greeter_session)
 480 {
 481     greeter_clear_hints (greeter_session);
 482     greeter_set_hint (greeter_session, "default-session", seat_get_string_property (seat, "user-session"));
 483     greeter_set_hint (greeter_session, "hide-users", seat_get_boolean_property (seat, "greeter-hide-users") ? "true" : "false");
 484     greeter_set_hint (greeter_session, "show-manual-login", seat_get_boolean_property (seat, "greeter-show-manual-login") ? "true" : "false");
 485     greeter_set_hint (greeter_session, "show-remote-login", seat_get_boolean_property (seat, "greeter-show-remote-login") ? "true" : "false");
 486     greeter_set_hint (greeter_session, "has-guest-account", seat_get_allow_guest (seat) && seat_get_boolean_property (seat, "greeter-allow-guest") ? "true" : "false");
 487 }
 488
 489 static void
 490 switch_to_greeter_from_failed_session (Seat *seat, Session *session)
 491 {
 492     Greeter *greeter_session;
 493     gboolean existing = FALSE;
 494
 495     /* Switch to greeter if one open */
 496     greeter_session = find_resettable_greeter (seat);
 497     if (greeter_session)
 498     {
 499         l_debug (seat, "Switching to existing greeter");
 500         set_greeter_hints (seat, greeter_session);
 501         existing = TRUE;
 502     }
 503     else
 504     {
 505         greeter_session = create_greeter_session (seat);
 506     }
 507
 508     if (session_get_is_guest (session))
 509         greeter_set_hint (greeter_session, "select-guest", "true");
 510     else
 511         greeter_set_hint (greeter_session, "select-user", session_get_username (session));
 512
 513     if (existing)
 514     {
 515         greeter_reset (greeter_session);
 516         seat_set_active_session (seat, SESSION (greeter_session));
 517     }
 518     else
 519     {
 520         if (seat->priv->session_to_activate)
 521             g_object_unref (seat->priv->session_to_activate);
 522         seat->priv->session_to_activate = g_object_ref (greeter_session);
 523
 524         if (can_share_display_server (seat, session_get_display_server (session)))
 525             session_set_display_server (SESSION (greeter_session), session_get_display_server (session));
 526         else
 527         {
 528             DisplayServer *display_server;
 529
 530             display_server = create_display_server (seat, session);
 531             session_set_display_server (session, display_server);
 532             if (!display_server_start (display_server))
 533             {
 534                 l_debug (seat, "Failed to start display server for greeter");
 535                 seat_stop (seat);
 536             }
 537         }
 538
 539         start_session (seat, SESSION (greeter_session));
 540     }
 541
 542     /* Stop failed session */
 543     session_stop (session);
 544 }
 545
 546 static void
 547 start_session (Seat *seat, Session *session)
 548 {
 549     /* Use system location for greeter log file */
 550     if (IS_GREETER (session))
 551     {
 552         gchar *log_dir, *filename, *log_filename;
 553
 554         log_dir = config_get_string (config_get_instance (), "LightDM", "log-directory");
 555         filename = g_strdup_printf ("%s-greeter.log", display_server_get_name (session_get_display_server (session)));
 556         log_filename = g_build_filename (log_dir, filename, NULL);
 557         g_free (log_dir);
 558         g_free (filename);
 559         session_set_log_file (session, log_filename);
 560         g_free (log_filename);
 561     }
 562
 563     if (session_start (session))
 564         return;
 565
 566     if (IS_GREETER (session))
 567     {
 568         l_debug (seat, "Failed to start greeter");
 569         display_server_stop (session_get_display_server (session));
 570         return;
 571     }
 572
 573     l_debug (seat, "Failed to start session, starting greeter");
 574     switch_to_greeter_from_failed_session (seat, session);
 575 }
 576
 577 static void
 578 run_session (Seat *seat, Session *session)
 579 {
 580     const gchar *script;
 581
 582     if (IS_GREETER (session))
 583         script = seat_get_string_property (seat, "greeter-setup-script");
 584     else
 585         script = seat_get_string_property (seat, "session-setup-script");
 586     if (script && !run_script (seat, session_get_display_server (session), script, session_get_user (session)))
 587     {
 588         l_debug (seat, "Switching to greeter due to failed setup script");
 589         switch_to_greeter_from_failed_session (seat, session);
 590         return;
 591     }
 592
 593     if (!IS_GREETER (session))
 594     {
 595         g_signal_emit (seat, signals[RUNNING_USER_SESSION], 0, session);
 596         emit_upstart_signal ("desktop-session-start");
 597     }
 598
 599     session_run (session);
 600
 601     // FIXME: Wait until the session is ready
 602
 603     if (session == seat->priv->session_to_activate)
 604     {
 605         seat_set_active_session (seat, session);
 606         g_object_unref (seat->priv->session_to_activate);
 607         seat->priv->session_to_activate = NULL;
 608     }
 609     else if (seat->priv->active_session)
 610     {
 611         /* Multiple sessions can theoretically be on the same VT (especially
 612            if using Mir).  If a new session appears on an existing active VT,
 613            logind will mark it as active, while ConsoleKit will re-mark the
 614            oldest session as active.  In either case, that may not be the
 615            session that we want to be active.  So let's be explicit and
 616            re-activate the correct session whenever a new session starts.
 617            There's no harm to do this in seats that enforce separate VTs. */
 618         session_activate (seat->priv->active_session);
 619     }
 620 }
 621
 622 static Session *
 623 find_user_session (Seat *seat, const gchar *username, Session *ignore_session)
 624 {
 625     GList *link;
 626
 627     if (!username)
 628         return NULL;
 629
 630     for (link = seat->priv->sessions; link; link = link->next)
 631     {
 632         Session *session = link->data;
 633
 634         if (session == ignore_session)
 635             continue;
 636
 637         if (!session_get_is_stopping (session) && g_strcmp0 (session_get_username (session), username) == 0)
 638             return session;
 639     }
 640
 641     return NULL;
 642 }
 643
 644 static void
 645 greeter_active_username_changed_cb (Greeter *greeter, GParamSpec *pspec, Seat *seat)
 646 {
 647     Session *session;
 648
 649     session = find_user_session (seat, greeter_get_active_username (greeter), seat->priv->active_session);
 650
 651     if (seat->priv->next_session)
 652         g_object_unref (seat->priv->next_session);
 653     seat->priv->next_session = session ? g_object_ref (session) : NULL;
 654
 655     SEAT_GET_CLASS (seat)->set_next_session (seat, session);
 656 }
 657
 658 static void
 659 session_authentication_complete_cb (Session *session, Seat *seat)
 660 {
 661     if (session_get_is_authenticated (session))
 662     {
 663         Session *s;
 664
 665         s = find_user_session (seat, session_get_username (session), session);
 666         if (s)
 667         {
 668             l_debug (seat, "Session authenticated, switching to existing user session");
 669             seat_set_active_session (seat, s);
 670             session_stop (session);
 671         }
 672         else
 673         {
 674             l_debug (seat, "Session authenticated, running command");
 675             run_session (seat, session);
 676         }
 677     }
 678     else if (!IS_GREETER (session))
 679     {
 680         l_debug (seat, "Switching to greeter due to failed authentication");
 681         switch_to_greeter_from_failed_session (seat, session);
 682     }
 683     else
 684     {
 685         l_debug (seat, "Stopping session that failed authentication");
 686         session_stop (session);
 687     }
 688 }
 689
 690 static void
 691 session_stopped_cb (Session *session, Seat *seat)
 692 {
 693     DisplayServer *display_server;
 694
 695     l_debug (seat, "Session stopped");
 696
 697     g_signal_handlers_disconnect_matched (session, G_SIGNAL_MATCH_DATA, 0, 0, NULL, NULL, seat);
 698     seat->priv->sessions = g_list_remove (seat->priv->sessions, session);
 699     if (session == seat->priv->active_session)
 700     {
 701         g_object_unref (seat->priv->active_session);
 702         seat->priv->active_session = NULL;
 703     }
 704     if (session == seat->priv->next_session)
 705     {
 706         g_object_unref (seat->priv->next_session);
 707         seat->priv->next_session = NULL;
 708     }
 709     if (session == seat->priv->session_to_activate)
 710     {
 711         g_object_unref (seat->priv->session_to_activate);
 712         seat->priv->session_to_activate = NULL;
 713     }
 714
 715     display_server = session_get_display_server (session);
 716     if (!display_server)
 717     {
 718         g_object_unref (session);
 719         return;
 720     }
 721
 722     /* Cleanup */
 723     if (!IS_GREETER (session))
 724     {
 725         const gchar *script;
 726         script = seat_get_string_property (seat, "session-cleanup-script");
 727         if (script)
 728             run_script (seat, display_server, script, session_get_user (session));
 729     }
 730
 731     /* We were waiting for this session, but it didn't start :( */
 732     // FIXME: Start a greeter on this?
 733     if (session == seat->priv->session_to_activate)
 734     {
 735         g_object_unref (seat->priv->session_to_activate);
 736         seat->priv->session_to_activate = NULL;
 737     }
 738
 739     if (seat->priv->stopping)
 740     {
 741         check_stopped (seat);
 742         g_object_unref (session);
 743         return;
 744     }
 745
 746     /* If this is the greeter session then re-use this display server */
 747     if (IS_GREETER (session) &&
 748         can_share_display_server (seat, display_server) &&
 749         greeter_get_start_session (GREETER (session)))
 750     {
 751         GList *link;
 752
 753         for (link = seat->priv->sessions; link; link = link->next)
 754         {
 755             Session *s = link->data;
 756
 757             /* Skip this session and sessions on other display servers */
 758             if (s == session || session_get_display_server (s) != display_server || session_get_is_stopping (s))
 759                 continue;
 760
 761             if (session_get_is_authenticated (s))
 762             {
 763                 l_debug (seat, "Greeter stopped, running session");
 764                 run_session (seat, s);
 765             }
 766             else
 767             {
 768                 l_debug (seat, "Greeter stopped, starting session authentication");
 769                 start_session (seat, s);
 770             }
 771             break;
 772         }
 773     }
 774     /* If this is the greeter and nothing else is running then stop the seat */
 775     else if (IS_GREETER (session) &&
 776         !greeter_get_start_session (GREETER (session)) &&
 777         g_list_length (seat->priv->display_servers) == 1 &&
 778         g_list_nth_data (seat->priv->display_servers, 0) == display_server)
 779     {
 780         l_debug (seat, "Stopping; failed to start a greeter");
 781         seat_stop (seat);
 782     }
 783     /* If we were the active session, switch to a greeter */
 784     else if (!IS_GREETER (session) && session == seat_get_active_session (seat))
 785     {
 786         l_debug (seat, "Active session stopped, starting greeter");
 787         if (!seat_switch_to_greeter (seat))
 788         {
 789             l_debug (seat, "Stopping; failed to start a greeter");
 790             seat_stop (seat);
 791         }
 792     }
 793
 794     /* Stop the display server if no-longer required */
 795     if (display_server && !display_server_get_is_stopping (display_server))
 796     {
 797         GList *link;
 798         int n_sessions = 0;
 799
 800         for (link = seat->priv->sessions; link; link = link->next)
 801         {
 802             Session *s = link->data;
 803             if (s == session)
 804                 continue;
 805             if (session_get_display_server (s) == display_server)
 806                 n_sessions++;
 807         }
 808         if (n_sessions == 0)
 809         {
 810             l_debug (seat, "Stopping display server, no sessions require it");
 811             display_server_stop (display_server);
 812         }
 813     }
 814
 815     g_signal_emit (seat, signals[SESSION_REMOVED], 0, session);
 816     g_object_unref (session);
 817 }
 818
 819 static void
 820 set_session_env (Session *session)
 821 {
 822     /* Connect using the session bus */
 823     if (getuid () != 0)
 824     {
 825         if (g_getenv ("DBUS_SESSION_BUS_ADDRESS"))
 826             session_set_env (session, "DBUS_SESSION_BUS_ADDRESS", g_getenv ("DBUS_SESSION_BUS_ADDRESS"));
 827         session_set_env (session, "LDM_BUS", "SESSION");
 828         if (g_getenv ("LD_PRELOAD"))
 829             session_set_env (session, "LD_PRELOAD", g_getenv ("LD_PRELOAD"));
 830         if (g_getenv ("LD_LIBRARY_PATH"))
 831             session_set_env (session, "LD_LIBRARY_PATH", g_getenv ("LD_LIBRARY_PATH"));
 832         if (g_getenv ("PATH"))
 833             session_set_env (session, "PATH", g_getenv ("PATH"));
 834     }
 835
 836     /* Variables required for regression tests */
 837     if (g_getenv ("LIGHTDM_TEST_ROOT"))
 838     {
 839         session_set_env (session, "LIGHTDM_TEST_ROOT", g_getenv ("LIGHTDM_TEST_ROOT"));
 840         session_set_env (session, "DBUS_SYSTEM_BUS_ADDRESS", g_getenv ("DBUS_SYSTEM_BUS_ADDRESS"));
 841         session_set_env (session, "DBUS_SESSION_BUS_ADDRESS", g_getenv ("DBUS_SESSION_BUS_ADDRESS"));
 842         session_set_env (session, "LD_PRELOAD", g_getenv ("LD_PRELOAD"));
 843         session_set_env (session, "LD_LIBRARY_PATH", g_getenv ("LD_LIBRARY_PATH"));
 844         session_set_env (session, "GI_TYPELIB_PATH", g_getenv ("GI_TYPELIB_PATH"));
 845     }
 846 }
 847
 848 static Session *
 849 create_session (Seat *seat, gboolean autostart)
 850 {
 851     Session *session;
 852
 853     session = SEAT_GET_CLASS (seat)->create_session (seat);
 854     seat->priv->sessions = g_list_append (seat->priv->sessions, session);
 855     if (autostart)
 856         g_signal_connect (session, "authentication-complete", G_CALLBACK (session_authentication_complete_cb), seat);
 857     g_signal_connect (session, "stopped", G_CALLBACK (session_stopped_cb), seat);
 858
 859     set_session_env (session);
 860
 861     g_signal_emit (seat, signals[SESSION_ADDED], 0, session);
 862
 863     return session;
 864 }
 865
 866 static gchar **
 867 get_session_argv (Seat *seat, SessionConfig *session_config, const gchar *session_wrapper)
 868 {
 869     gboolean result;
 870     int argc;
 871     gchar **argv, *path;
 872     GError *error = NULL;
 873
 874     /* If configured, run sessions through a wrapper */
 875     if (session_wrapper)
 876     {
 877         argv = g_malloc (sizeof (gchar *) * 3);
 878         path = g_find_program_in_path (session_wrapper);
 879         argv[0] = path ? path : g_strdup (session_wrapper);
 880         argv[1] = g_strdup (session_config_get_command (session_config));
 881         argv[2] = NULL;
 882         return argv;
 883     }
 884
 885     /* Split command into an array listing and make command absolute */
 886     result = g_shell_parse_argv (session_config_get_command (session_config), &argc, &argv, &error);
 887     if (error)
 888         l_debug (seat, "Invalid session command '%s': %s", session_config_get_command (session_config), error->message);
 889     g_clear_error (&error);
 890     if (!result)
 891         return NULL;
 892     path = g_find_program_in_path (argv[0]);
 893     if (path)
 894     {
 895         g_free (argv[0]);
 896         argv[0] = path;
 897     }
 898
 899     return argv;
 900 }
 901
 902 static SessionConfig *
 903 find_session_config (Seat *seat, const gchar *sessions_dir, const gchar *session_name)
 904 {
 905     gchar **dirs;
 906     SessionConfig *session_config = NULL;
 907     int i;
 908     GError *error = NULL;
 909
 910     g_return_val_if_fail (sessions_dir != NULL, NULL);
 911     g_return_val_if_fail (session_name != NULL, NULL);
 912
 913     dirs = g_strsplit (sessions_dir, ":", -1);
 914     for (i = 0; dirs[i]; i++)
 915     {
 916         gchar *filename, *path;
 917
 918         filename = g_strdup_printf ("%s.desktop", session_name);
 919         path = g_build_filename (dirs[i], filename, NULL);
 920         g_free (filename);
 921         session_config = session_config_new_from_file (path, &error);
 922         g_free (path);
 923         if (session_config)
 924             break;
 925
 926         if (dirs[i+1] == NULL)
 927             l_debug (seat, "Failed to find session configuration %s", session_name);
 928         g_clear_error (&error);
 929     }
 930     g_strfreev (dirs);
 931
 932     return session_config;
 933 }
 934
 935 static void
 936 configure_session (Session *session, SessionConfig *config, const gchar *session_name, const gchar *language)
 937 {
 938     const gchar *desktop_name;
 939
 940     session_set_config (session, config);
 941     session_set_env (session, "XDG_SESSION_DESKTOP", session_name);
 942     session_set_env (session, "DESKTOP_SESSION", session_name);
 943     session_set_env (session, "GDMSESSION", session_name);
 944     desktop_name = session_config_get_desktop_name (config);
 945     if (desktop_name)
 946         session_set_env (session, "XDG_CURRENT_DESKTOP", desktop_name);
 947     if (language && language[0] != '\0')
 948     {
 949         session_set_env (session, "LANG", language);
 950         session_set_env (session, "GDM_LANG", language);
 951     }
 952 }
 953
 954 static Session *
 955 create_user_session (Seat *seat, const gchar *username, gboolean autostart)
 956 {
 957     User *user;
 958     gchar *sessions_dir;
 959     const gchar *session_name, *language;
 960     SessionConfig *session_config;
 961     Session *session = NULL;
 962
 963     l_debug (seat, "Creating user session");
 964
 965     /* Load user preferences */
 966     user = accounts_get_user_by_name (username);
 967     if (!user)
 968     {
 969         l_debug (seat, "Can't login unknown user '%s'", username);
 970         return NULL;
 971     }
 972     session_name = user_get_xsession (user);
 973     language = user_get_language (user);
 974
 975     if (!session_name)
 976         session_name = seat_get_string_property (seat, "user-session");
 977     sessions_dir = config_get_string (config_get_instance (), "LightDM", "sessions-directory");
 978     session_config = find_session_config (seat, sessions_dir, session_name);
 979     g_free (sessions_dir);
 980     if (session_config)
 981     {
 982         gchar **argv;
 983
 984         session = create_session (seat, autostart);
 985         configure_session (session, session_config, session_name, language);
 986         session_set_username (session, username);
 987         session_set_do_authenticate (session, TRUE);
 988         argv = get_session_argv (seat, session_config, seat_get_string_property (seat, "session-wrapper"));
 989         session_set_argv (session, argv);
 990         g_strfreev (argv);
 991         g_object_unref (session_config);
 992     }
 993     else
 994         l_debug (seat, "Can't find session '%s'", session_name);
 995
 996     g_object_unref (user);
 997
 998     return session;
 999 }
1000
1001 static void
1002 prepend_argv (gchar ***argv, const gchar *value)
1003 {
1004     gchar **old_argv, **new_argv;
1005     gint i;
1006
1007     old_argv = *argv;
1008     new_argv = g_malloc (sizeof (gchar *) * (g_strv_length (*argv) + 2));
1009     new_argv[0] = g_strdup (value);
1010     for (i = 0; old_argv[i]; i++)
1011         new_argv[i + 1] = old_argv[i];
1012     new_argv[i + 1] = NULL;
1013
1014     g_free (*argv);
1015     *argv = new_argv;
1016 }
1017
1018 static Session *
1019 create_guest_session (Seat *seat, const gchar *session_name)
1020 {
1021     const gchar *guest_wrapper;
1022     gchar *sessions_dir, **argv;
1023     SessionConfig *session_config;
1024     Session *session;
1025
1026     if (!session_name)
1027         session_name = seat_get_string_property (seat, "guest-session");
1028     if (!session_name)
1029         session_name = seat_get_string_property (seat, "user-session");
1030     sessions_dir = config_get_string (config_get_instance (), "LightDM", "sessions-directory");
1031     session_config = find_session_config (seat, sessions_dir, session_name);
1032     g_free (sessions_dir);
1033     if (!session_config)
1034     {
1035         l_debug (seat, "Can't find session '%s'", session_name);
1036         return NULL;
1037     }
1038
1039     session = create_session (seat, TRUE);
1040     configure_session (session, session_config, session_name, NULL);
1041     session_set_do_authenticate (session, TRUE);
1042     session_set_is_guest (session, TRUE);
1043     argv = get_session_argv (seat, session_config, seat_get_string_property (seat, "session-wrapper"));
1044     guest_wrapper = seat_get_string_property (seat, "guest-wrapper");
1045     if (guest_wrapper)
1046     {
1047         gchar *path;
1048         path = g_find_program_in_path (guest_wrapper);
1049         prepend_argv (&argv, path ? path : guest_wrapper);
1050         g_free (path);
1051     }
1052
1053     session_set_argv (session, argv);
1054     g_strfreev (argv);
1055     g_object_unref (session_config);
1056
1057     return session;
1058 }
1059
1060 static Session *
1061 greeter_create_session_cb (Greeter *greeter, Seat *seat)
1062 {
1063     Session *session;
1064
1065     session = create_session (seat, FALSE);
1066     session_set_config (session, session_get_config (SESSION (greeter)));
1067     session_set_display_server (session, session_get_display_server (SESSION (greeter)));
1068
1069     return g_object_ref (session);
1070 }
1071
1072 static gboolean
1073 greeter_start_session_cb (Greeter *greeter, SessionType type, const gchar *session_name, Seat *seat)
1074 {
1075     Session *session, *existing_session;
1076     const gchar *username;
1077     DisplayServer *display_server;
1078
1079     /* Get the session to use */
1080     if (greeter_get_guest_authenticated (greeter))
1081     {
1082         session = create_guest_session (seat, session_name);
1083         if (!session)
1084             return FALSE;
1085         session_set_pam_service (session, seat_get_string_property (seat, "pam-autologin-service"));
1086     }
1087     else
1088     {
1089         const gchar *language = NULL;
1090         SessionConfig *session_config;
1091         User *user;
1092         gchar *sessions_dir = NULL;
1093         gchar **argv;
1094
1095         session = greeter_get_authentication_session (greeter);
1096
1097         /* Get session command to run */
1098         switch (type)
1099         {
1100         case SESSION_TYPE_LOCAL:
1101             sessions_dir = config_get_string (config_get_instance (), "LightDM", "sessions-directory");
1102             break;
1103         case SESSION_TYPE_REMOTE:
1104             sessions_dir = config_get_string (config_get_instance (), "LightDM", "remote-sessions-directory");
1105             break;
1106         }
1107
1108         /* Load user preferences */
1109         user = session_get_user (session);
1110         if (user)
1111         {
1112             if (!session_name)
1113                 session_name = user_get_xsession (user);
1114             language = user_get_language (user);
1115         }
1116
1117         if (!session_name)
1118             session_name = seat_get_string_property (seat, "user-session");
1119         if (user)
1120             user_set_xsession (session_get_user (session), session_name);
1121
1122         session_config = find_session_config (seat, sessions_dir, session_name);
1123         g_free (sessions_dir);
1124         if (!session_config)
1125         {
1126             l_debug (seat, "Can't find session '%s'", session_name);
1127             return FALSE;
1128         }
1129
1130         configure_session (session, session_config, session_name, language);
1131         argv = get_session_argv (seat, session_config, seat_get_string_property (seat, "session-wrapper"));
1132         session_set_argv (session, argv);
1133         g_strfreev (argv);
1134         g_object_unref (session_config);
1135     }
1136
1137     /* Switch to this session when it is ready */
1138     if (seat->priv->session_to_activate)
1139         g_object_unref (seat->priv->session_to_activate);
1140     seat->priv->session_to_activate = g_object_ref (session);
1141
1142     /* Return to existing session if it is open */
1143     username = session_get_username (session);
1144     existing_session = find_user_session (seat, username, NULL);
1145     if (existing_session && session != existing_session)
1146     {
1147         l_debug (seat, "Returning to existing user session %s", username);
1148         session_stop (session);
1149         session_unlock (existing_session);
1150         seat_set_active_session (seat, existing_session);
1151         return TRUE;
1152     }
1153
1154     /* If can re-use the display server, stop the greeter first */
1155     display_server = session_get_display_server (SESSION (greeter));
1156     if (!greeter_get_resettable (greeter) &&
1157         can_share_display_server (seat, display_server) &&
1158         strcmp (display_server_get_session_type (display_server), session_get_session_type (session)) == 0)
1159     {
1160         l_debug (seat, "Stopping greeter; display server will be re-used for user session");
1161
1162         /* Run on the same display server after the greeter has stopped */
1163         session_set_display_server (session, display_server);
1164
1165         /* Stop the greeter */
1166         session_stop (SESSION (greeter));
1167
1168         return TRUE;
1169     }
1170     /* Otherwise start a new display server for this session */
1171     else
1172     {
1173         display_server = create_display_server (seat, session);
1174         session_set_display_server (session, display_server);
1175         if (!display_server_start (display_server))
1176         {
1177             l_debug (seat, "Failed to start display server for new session");
1178             return FALSE;
1179         }
1180
1181         return TRUE;
1182     }
1183 }
1184
1185 static Greeter *
1186 create_greeter_session (Seat *seat)
1187 {
1188     gchar *sessions_dir, **argv;
1189     SessionConfig *session_config;
1190     Greeter *greeter_session;
1191     const gchar *greeter_wrapper;
1192     const gchar *autologin_username;
1193     int autologin_timeout;
1194     gboolean autologin_guest;
1195
1196     l_debug (seat, "Creating greeter session");
1197
1198     sessions_dir = config_get_string (config_get_instance (), "LightDM", "greeters-directory");
1199     session_config = find_session_config (seat, sessions_dir, seat_get_string_property (seat, "greeter-session"));
1200     g_free (sessions_dir);
1201     if (!session_config)
1202         return NULL;
1203
1204     argv = get_session_argv (seat, session_config, NULL);
1205     greeter_wrapper = seat_get_string_property (seat, "greeter-wrapper");
1206     if (greeter_wrapper)
1207     {
1208         gchar *path;
1209         path = g_find_program_in_path (greeter_wrapper);
1210         prepend_argv (&argv, path ? path : greeter_wrapper);
1211         g_free (path);
1212     }
1213
1214     greeter_session = SEAT_GET_CLASS (seat)->create_greeter_session (seat);
1215     session_set_config (SESSION (greeter_session), session_config);
1216     seat->priv->sessions = g_list_append (seat->priv->sessions, SESSION (greeter_session));
1217     g_signal_connect (greeter_session, "notify::active-username", G_CALLBACK (greeter_active_username_changed_cb), seat);
1218     g_signal_connect (greeter_session, "authentication-complete", G_CALLBACK (session_authentication_complete_cb), seat);
1219     g_signal_connect (greeter_session, "stopped", G_CALLBACK (session_stopped_cb), seat);
1220
1221     set_session_env (SESSION (greeter_session));
1222     session_set_env (SESSION (greeter_session), "XDG_SESSION_CLASS", "greeter");
1223
1224     session_set_pam_service (SESSION (greeter_session), seat_get_string_property (seat, "pam-greeter-service"));
1225     if (getuid () == 0)
1226     {
1227         gchar *greeter_user;
1228         greeter_user = config_get_string (config_get_instance (), "LightDM", "greeter-user");
1229         session_set_username (SESSION (greeter_session), greeter_user);
1230         g_free (greeter_user);
1231     }
1232     else
1233     {
1234         /* In test mode run the greeter as ourself */
1235         session_set_username (SESSION (greeter_session), user_get_name (accounts_get_current_user ()));
1236     }
1237     session_set_argv (SESSION (greeter_session), argv);
1238     g_strfreev (argv);
1239
1240     greeter_set_pam_services (greeter_session,
1241                               seat_get_string_property (seat, "pam-service"),
1242                               seat_get_string_property (seat, "pam-autologin-service"));
1243     g_signal_connect (greeter_session, "create-session", G_CALLBACK (greeter_create_session_cb), seat);
1244     g_signal_connect (greeter_session, "start-session", G_CALLBACK (greeter_start_session_cb), seat);
1245
1246     /* Set hints to greeter */
1247     greeter_set_allow_guest (greeter_session, seat_get_allow_guest (seat));
1248     set_greeter_hints (seat, greeter_session);
1249
1250     /* Configure for automatic login */
1251     autologin_username = seat_get_string_property (seat, "autologin-user");
1252     if (g_strcmp0 (autologin_username, "") == 0)
1253         autologin_username = NULL;
1254     autologin_timeout = seat_get_integer_property (seat, "autologin-user-timeout");
1255     autologin_guest = seat_get_boolean_property (seat, "autologin-guest");
1256     if (autologin_timeout > 0)
1257     {
1258         gchar *value;
1259
1260         value = g_strdup_printf ("%d", autologin_timeout);
1261         greeter_set_hint (greeter_session, "autologin-timeout", value);
1262         g_free (value);
1263         if (autologin_username)
1264             greeter_set_hint (greeter_session, "autologin-user", autologin_username);
1265         if (autologin_guest)
1266             greeter_set_hint (greeter_session, "autologin-guest", "true");
1267     }
1268
1269     g_object_unref (session_config);
1270
1271     return greeter_session;
1272 }
1273
1274 static Session *
1275 find_session_for_display_server (Seat *seat, DisplayServer *display_server)
1276 {
1277     GList *link;
1278
1279     for (link = seat->priv->sessions; link; link = link->next)
1280     {
1281         Session *session = link->data;
1282         if (session_get_display_server (session) == display_server && !session_get_is_stopping (session))
1283             return session;
1284     }
1285
1286     return NULL;
1287 }
1288
1289 static void
1290 display_server_ready_cb (DisplayServer *display_server, Seat *seat)
1291 {
1292     const gchar *script;
1293     Session *session;
1294
1295     /* Run setup script */
1296     script = seat_get_string_property (seat, "display-setup-script");
1297     if (script && !run_script (seat, display_server, script, NULL))
1298     {
1299         l_debug (seat, "Stopping display server due to failed setup script");
1300         display_server_stop (display_server);
1301         return;
1302     }
1303
1304     emit_upstart_signal ("login-session-start");
1305
1306     /* Start the session waiting for this display server */
1307     session = find_session_for_display_server (seat, display_server);
1308     if (session)
1309     {
1310         if (session_get_is_authenticated (session))
1311         {
1312             l_debug (seat, "Display server ready, running session");
1313             run_session (seat, session);
1314         }
1315         else
1316         {
1317             l_debug (seat, "Display server ready, starting session authentication");
1318             start_session (seat, session);
1319         }
1320     }
1321     else
1322     {
1323         l_debug (seat, "Stopping not required display server");
1324         display_server_stop (display_server);
1325     }
1326 }
1327
1328 static DisplayServer *
1329 create_display_server (Seat *seat, Session *session)
1330 {
1331     DisplayServer *display_server;
1332
1333     l_debug (seat, "Creating display server of type %s", session_get_session_type (session));
1334
1335     display_server = SEAT_GET_CLASS (seat)->create_display_server (seat, session);
1336     if (!display_server)
1337         return NULL;
1338
1339     seat->priv->display_servers = g_list_append (seat->priv->display_servers, display_server);
1340     g_signal_connect (display_server, "ready", G_CALLBACK (display_server_ready_cb), seat);
1341     g_signal_connect (display_server, "stopped", G_CALLBACK (display_server_stopped_cb), seat);
1342
1343     return display_server;
1344 }
1345
1346 gboolean
1347 seat_switch_to_greeter (Seat *seat)
1348 {
1349     Greeter *greeter_session;
1350     DisplayServer *display_server;
1351
1352     g_return_val_if_fail (seat != NULL, FALSE);
1353
1354     if (!seat_get_can_switch (seat))
1355         return FALSE;
1356
1357     /* Switch to greeter if one open */
1358     greeter_session = find_greeter_session (seat);
1359     if (greeter_session)
1360     {
1361         l_debug (seat, "Switching to existing greeter");
1362         seat_set_active_session (seat, SESSION (greeter_session));
1363         return TRUE;
1364     }
1365
1366     greeter_session = create_greeter_session (seat);
1367     if (!greeter_session)
1368         return FALSE;
1369
1370     if (seat->priv->session_to_activate)
1371         g_object_unref (seat->priv->session_to_activate);
1372     seat->priv->session_to_activate = g_object_ref (greeter_session);
1373
1374     display_server = create_display_server (seat, SESSION (greeter_session));
1375     session_set_display_server (SESSION (greeter_session), display_server);
1376
1377     return display_server_start (display_server);
1378 }
1379
1380 static void
1381 switch_authentication_complete_cb (Session *session, Seat *seat)
1382 {
1383     Greeter *greeter_session;
1384     DisplayServer *display_server;
1385     gboolean existing = FALSE;
1386
1387     /* If authenticated, then unlock existing session or start new one */
1388     if (session_get_is_authenticated (session))
1389     {
1390         Session *s;
1391
1392         s = find_user_session (seat, session_get_username (session), session);
1393         if (s)
1394         {
1395             l_debug (seat, "Session authenticated, switching to existing user session");
1396             session_unlock (s);
1397             seat_set_active_session (seat, s);
1398             session_stop (session);
1399         }
1400         else
1401         {
1402             l_debug (seat, "Session authenticated, starting display server");
1403             if (seat->priv->session_to_activate)
1404                 g_object_unref (seat->priv->session_to_activate);
1405             seat->priv->session_to_activate = g_object_ref (session);
1406             display_server = create_display_server (seat, session);
1407             session_set_display_server (session, display_server);
1408             display_server_start (display_server);
1409         }
1410
1411         return;
1412     }
1413
1414     session_stop (session);
1415
1416     /* See if we already have a greeter up and reuse it if so */
1417     greeter_session = find_resettable_greeter (seat);
1418     if (greeter_session)
1419     {
1420         l_debug (seat, "Switching to existing greeter to authenticate session");
1421         set_greeter_hints (seat, greeter_session);
1422         existing = TRUE;
1423     }
1424     else
1425     {
1426         l_debug (seat, "Starting greeter to authenticate session");
1427         greeter_session = create_greeter_session (seat);
1428     }
1429
1430     if (session_get_is_guest (session))
1431         greeter_set_hint (greeter_session, "select-guest", "true");
1432     else
1433         greeter_set_hint (greeter_session, "select-user", session_get_username (session));
1434
1435     if (existing)
1436     {
1437         greeter_reset (greeter_session);
1438         seat_set_active_session (seat, SESSION (greeter_session));
1439     }
1440     else
1441     {
1442         if (seat->priv->session_to_activate)
1443             g_object_unref (seat->priv->session_to_activate);
1444         seat->priv->session_to_activate = g_object_ref (greeter_session);
1445
1446         display_server = create_display_server (seat, SESSION (greeter_session));
1447         session_set_display_server (SESSION (greeter_session), display_server);
1448         display_server_start (display_server);
1449     }
1450 }
1451
1452 gboolean
1453 seat_switch_to_user (Seat *seat, const gchar *username, const gchar *session_name)
1454 {
1455     Session *session;
1456
1457     g_return_val_if_fail (seat != NULL, FALSE);
1458     g_return_val_if_fail (username != NULL, FALSE);
1459
1460     if (!seat_get_can_switch (seat))
1461         return FALSE;
1462
1463     /* If we're already on this session, then ignore */
1464     session = find_user_session (seat, username, NULL);
1465     if (session && session == seat->priv->active_session)
1466         return TRUE;
1467
1468     l_debug (seat, "Switching to user %s", username);
1469
1470     /* Attempt to authenticate them */
1471     session = create_user_session (seat, username, FALSE);
1472     g_signal_connect (session, "authentication-complete", G_CALLBACK (switch_authentication_complete_cb), seat);
1473     session_set_pam_service (session, seat_get_string_property (seat, "pam-service"));
1474
1475     return session_start (session);
1476 }
1477
1478 static Session *
1479 find_guest_session (Seat *seat)
1480 {
1481     GList *link;
1482
1483     for (link = seat->priv->sessions; link; link = link->next)
1484     {
1485         Session *session = link->data;
1486         if (!session_get_is_stopping (session) && session_get_is_guest (session))
1487             return session;
1488     }
1489
1490     return NULL;
1491 }
1492
1493 gboolean
1494 seat_switch_to_guest (Seat *seat, const gchar *session_name)
1495 {
1496     Session *session;
1497     DisplayServer *display_server;
1498
1499     g_return_val_if_fail (seat != NULL, FALSE);
1500
1501     if (!seat_get_can_switch (seat) || !seat_get_allow_guest (seat))
1502         return FALSE;
1503
1504     /* Switch to session if one open */
1505     session = find_guest_session (seat);
1506     if (session)
1507     {
1508         l_debug (seat, "Switching to existing guest account %s", session_get_username (session));
1509         seat_set_active_session (seat, session);
1510         return TRUE;
1511     }
1512
1513     session = create_guest_session (seat, session_name);
1514     if (!session)
1515         return FALSE;
1516
1517     display_server = create_display_server (seat, session);
1518
1519     if (seat->priv->session_to_activate)
1520         g_object_unref (seat->priv->session_to_activate);
1521     seat->priv->session_to_activate = g_object_ref (session);
1522     session_set_pam_service (session, seat_get_string_property (seat, "pam-autologin-service"));
1523     session_set_display_server (session, display_server);
1524
1525     return display_server_start (display_server);
1526 }
1527
1528 gboolean
1529 seat_lock (Seat *seat, const gchar *username)
1530 {
1531     Greeter *greeter_session;
1532     DisplayServer *display_server;
1533     gboolean existing = FALSE;
1534
1535     g_return_val_if_fail (seat != NULL, FALSE);
1536
1537     if (!seat_get_can_switch (seat))
1538         return FALSE;
1539
1540     l_debug (seat, "Locking");
1541
1542     /* Switch to greeter we can reuse */
1543     greeter_session = find_resettable_greeter (seat);
1544     if (greeter_session)
1545     {
1546         l_debug (seat, "Switching to existing greeter");
1547         set_greeter_hints (seat, greeter_session);
1548         existing = TRUE;
1549     }
1550     else
1551     {
1552         greeter_session = create_greeter_session (seat);
1553         if (!greeter_session)
1554             return FALSE;
1555     }
1556
1557     greeter_set_hint (greeter_session, "lock-screen", "true");
1558     if (username)
1559         greeter_set_hint (greeter_session, "select-user", username);
1560
1561     if (existing)
1562     {
1563         greeter_reset (greeter_session);
1564         seat_set_active_session (seat, SESSION (greeter_session));
1565         return TRUE;
1566     }
1567     else
1568     {
1569         display_server = create_display_server (seat, SESSION (greeter_session));
1570
1571         if (seat->priv->session_to_activate)
1572             g_object_unref (seat->priv->session_to_activate);
1573         seat->priv->session_to_activate = g_object_ref (greeter_session);
1574         session_set_display_server (SESSION (greeter_session), display_server);
1575
1576         return display_server_start (display_server);
1577     }
1578 }
1579
1580 void
1581 seat_stop (Seat *seat)
1582 {
1583     g_return_if_fail (seat != NULL);
1584
1585     if (seat->priv->stopping)
1586         return;
1587
1588     l_debug (seat, "Stopping");
1589     seat->priv->stopping = TRUE;
1590     SEAT_GET_CLASS (seat)->stop (seat);
1591 }
1592
1593 gboolean
1594 seat_get_is_stopping (Seat *seat)
1595 {
1596     g_return_val_if_fail (seat != NULL, FALSE);
1597     return seat->priv->stopping;
1598 }
1599
1600 static void
1601 seat_real_setup (Seat *seat)
1602 {
1603 }
1604
1605 static gboolean
1606 seat_real_start (Seat *seat)
1607 {
1608     const gchar *autologin_username;
1609     int autologin_timeout;
1610     gboolean autologin_guest;
1611     gboolean autologin_in_background;
1612     Session *session = NULL, *background_session = NULL;
1613
1614     /* Get autologin settings */
1615     autologin_username = seat_get_string_property (seat, "autologin-user");
1616     if (g_strcmp0 (autologin_username, "") == 0)
1617         autologin_username = NULL;
1618     autologin_timeout = seat_get_integer_property (seat, "autologin-user-timeout");
1619     autologin_guest = seat_get_boolean_property (seat, "autologin-guest");
1620     autologin_in_background = seat_get_boolean_property (seat, "autologin-in-background");
1621
1622     /* Autologin if configured */
1623     if (autologin_timeout == 0 || autologin_in_background)
1624     {
1625         if (autologin_guest)
1626             session = create_guest_session (seat, NULL);
1627         else if (autologin_username != NULL)
1628             session = create_user_session (seat, autologin_username, TRUE);
1629
1630         if (session)
1631             session_set_pam_service (session, seat_get_string_property (seat, "pam-autologin-service"));
1632
1633         /* Load in background if required */
1634         if (autologin_in_background && session)
1635         {
1636             background_session = session;
1637             session = NULL;
1638         }
1639
1640         if (session)
1641         {
1642             DisplayServer *display_server;
1643
1644             if (seat->priv->session_to_activate)
1645                 g_object_unref (seat->priv->session_to_activate);
1646             seat->priv->session_to_activate = g_object_ref (session);
1647
1648             display_server = create_display_server (seat, session);
1649             session_set_display_server (session, display_server);
1650             if (!display_server || !display_server_start (display_server))
1651             {
1652                 l_debug (seat, "Can't create display server for automatic login");
1653                 session_stop (session);
1654                 if (display_server)
1655                     display_server_stop (display_server);
1656                 session = NULL;
1657             }
1658         }
1659     }
1660
1661     /* Fallback to a greeter */
1662     if (!session)
1663     {
1664         Greeter *greeter_session;
1665         DisplayServer *display_server;
1666
1667         greeter_session = create_greeter_session (seat);
1668         if (!greeter_session)
1669         {
1670             l_debug (seat, "Failed to create greeter session");
1671             return FALSE;
1672         }
1673
1674         if (seat->priv->session_to_activate)
1675             g_object_unref (seat->priv->session_to_activate);
1676         seat->priv->session_to_activate = g_object_ref (greeter_session);
1677         session = SESSION (greeter_session);
1678
1679         display_server = create_display_server (seat, session);
1680         session_set_display_server (session, display_server);
1681         if (!display_server || !display_server_start (display_server))
1682         {
1683             l_debug (seat, "Can't create display server for greeter");
1684             session_stop (session);
1685             if (display_server)
1686                 display_server_stop (display_server);
1687             session = NULL;
1688         }
1689     }
1690
1691     /* Fail if can't start a session */
1692     if (!session)
1693     {
1694         seat_stop (seat);
1695         return FALSE;
1696     }
1697
1698     /* Start background session */
1699     if (background_session)
1700     {
1701         DisplayServer *background_display_server;
1702
1703         background_display_server = create_display_server (seat, background_session);
1704         session_set_display_server (background_session, background_display_server);
1705         if (!display_server_start (background_display_server))
1706             l_warning (seat, "Failed to start display server for background session");
1707     }
1708
1709     return TRUE;
1710 }
1711
1712 static Greeter *
1713 seat_real_create_greeter_session (Seat *seat)
1714 {
1715     return greeter_new ();
1716 }
1717
1718 static Session *
1719 seat_real_create_session (Seat *seat)
1720 {
1721     return session_new ();
1722 }
1723
1724 static void
1725 seat_real_set_active_session (Seat *seat, Session *session)
1726 {
1727 }
1728
1729 static void
1730 seat_real_set_next_session (Seat *seat, Session *session)
1731 {
1732 }
1733
1734 static Session *
1735 seat_real_get_active_session (Seat *seat)
1736 {
1737     return NULL;
1738 }
1739
1740 static void
1741 seat_real_stop (Seat *seat)
1742 {
1743     GList *list, *link;
1744
1745     check_stopped (seat);
1746     if (seat->priv->stopped)
1747         return;
1748
1749     /* Stop all the display servers and sessions on the seat. Copy the list as
1750      * it might be modified if a display server / session stops during this loop */
1751     list = g_list_copy (seat->priv->display_servers);
1752     for (link = list; link; link = link->next)
1753         g_object_ref (link->data);
1754     for (link = list; link; link = link->next)
1755     {
1756         DisplayServer *display_server = link->data;
1757         if (!display_server_get_is_stopping (display_server))
1758         {
1759             l_debug (seat, "Stopping display server");
1760             display_server_stop (display_server);
1761         }
1762     }
1763     g_list_free_full (list, g_object_unref);
1764     list = g_list_copy (seat->priv->sessions);
1765     for (link = list; link; link = link->next)
1766         g_object_ref (link->data);
1767     for (link = list; link; link = link->next)
1768     {
1769         Session *session = link->data;
1770         if (!session_get_is_stopping (session))
1771         {
1772             l_debug (seat, "Stopping session");
1773             session_stop (session);
1774         }
1775     }
1776     g_list_free_full (list, g_object_unref);
1777 }
1778
1779 static void
1780 seat_init (Seat *seat)
1781 {
1782     seat->priv = G_TYPE_INSTANCE_GET_PRIVATE (seat, SEAT_TYPE, SeatPrivate);
1783     seat->priv->properties = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, g_free);
1784     seat->priv->share_display_server = TRUE;
1785 }
1786
1787 static void
1788 seat_finalize (GObject *object)
1789 {
1790     Seat *self;
1791     GList *link;
1792
1793     self = SEAT (object);
1794
1795     g_hash_table_unref (self->priv->properties);
1796     for (link = self->priv->display_servers; link; link = link->next)
1797     {
1798         DisplayServer *display_server = link->data;
1799         g_signal_handlers_disconnect_matched (display_server, G_SIGNAL_MATCH_DATA, 0, 0, NULL, NULL, self);
1800     }
1801     g_list_free_full (self->priv->display_servers, g_object_unref);
1802     for (link = self->priv->sessions; link; link = link->next)
1803     {
1804         Session *session = link->data;
1805         g_signal_handlers_disconnect_matched (session, G_SIGNAL_MATCH_DATA, 0, 0, NULL, NULL, self);
1806     }
1807     g_list_free_full (self->priv->sessions, g_object_unref);
1808     if (self->priv->active_session)
1809         g_object_unref (self->priv->active_session);
1810     if (self->priv->next_session)
1811         g_object_unref (self->priv->next_session);
1812     if (self->priv->session_to_activate)
1813         g_object_unref (self->priv->session_to_activate);
1814
1815     G_OBJECT_CLASS (seat_parent_class)->finalize (object);
1816 }
1817
1818 static void
1819 seat_class_init (SeatClass *klass)
1820 {
1821     GObjectClass *object_class = G_OBJECT_CLASS (klass);
1822
1823     klass->setup = seat_real_setup;
1824     klass->start = seat_real_start;
1825     klass->create_greeter_session = seat_real_create_greeter_session;
1826     klass->create_session = seat_real_create_session;
1827     klass->set_active_session = seat_real_set_active_session;
1828     klass->get_active_session = seat_real_get_active_session;
1829     klass->set_next_session = seat_real_set_next_session;
1830     klass->run_script = seat_real_run_script;
1831     klass->stop = seat_real_stop;
1832
1833     object_class->finalize = seat_finalize;
1834
1835     g_type_class_add_private (klass, sizeof (SeatPrivate));
1836
1837     signals[SESSION_ADDED] =
1838         g_signal_new ("session-added",
1839                       G_TYPE_FROM_CLASS (klass),
1840                       G_SIGNAL_RUN_LAST,
1841                       G_STRUCT_OFFSET (SeatClass, session_added),
1842                       NULL, NULL,
1843                       NULL,
1844                       G_TYPE_NONE, 1, SESSION_TYPE);
1845     signals[RUNNING_USER_SESSION] =
1846         g_signal_new ("running-user-session",
1847                       G_TYPE_FROM_CLASS (klass),
1848                       G_SIGNAL_RUN_LAST,
1849                       G_STRUCT_OFFSET (SeatClass, running_user_session),
1850                       NULL, NULL,
1851                       NULL,
1852                       G_TYPE_NONE, 1, SESSION_TYPE);
1853     signals[SESSION_REMOVED] =
1854         g_signal_new ("session-removed",
1855                       G_TYPE_FROM_CLASS (klass),
1856                       G_SIGNAL_RUN_LAST,
1857                       G_STRUCT_OFFSET (SeatClass, session_removed),
1858                       NULL, NULL,
1859                       NULL,
1860                       G_TYPE_NONE, 1, SESSION_TYPE);
1861     signals[STOPPED] =
1862         g_signal_new ("stopped",
1863                       G_TYPE_FROM_CLASS (klass),
1864                       G_SIGNAL_RUN_LAST,
1865                       G_STRUCT_OFFSET (SeatClass, stopped),
1866                       NULL, NULL,
1867                       NULL,
1868                       G_TYPE_NONE, 0);
1869 }
1870
1871 static gint
1872 seat_real_logprefix (Logger *self, gchar *buf, gulong buflen)
1873 {
1874     Seat *seat = SEAT (self);
1875     const gchar *name = seat_get_string_property (seat, "seat-name");
1876     if (name)
1877         return g_snprintf (buf, buflen, "Seat %s: ", name);
1878     else
1879         return g_snprintf (buf, buflen, "Seat: ");
1880 }
1881
1882 static void
1883 seat_logger_iface_init (LoggerInterface *iface)
1884 {
1885     iface->logprefix = &seat_real_logprefix;
1886 }