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-session.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     /* XDG name for this seat */
  34     gchar *name;
  35
  36     /* Configuration for this seat */
  37     GHashTable *properties;
  38
  39     /* TRUE if this seat can run multiple sessions at once */
  40     gboolean supports_multi_session;
  41
  42     /* TRUE if display server can be shared for sessions */
  43     gboolean share_display_server;
  44
  45     /* The display servers on this seat */
  46     GList *display_servers;
  47
  48     /* The sessions on this seat */
  49     GList *sessions;
  50
  51     /* The last session set to active */
  52     Session *active_session;
  53
  54     /* The session belonging to the active greeter user */
  55     Session *next_session;
  56
  57     /* The session to set active when it starts */
  58     Session *session_to_activate;
  59
  60     /* TRUE once we have started */
  61     gboolean started;
  62
  63     /* TRUE if stopping this seat (waiting for displays to stop) */
  64     gboolean stopping;
  65
  66     /* TRUE if stopped */
  67     gboolean stopped;
  68
  69     /* The greeter to be started to replace the current one */
  70     GreeterSession *replacement_greeter;
  71 };
  72
  73 static void seat_logger_iface_init (LoggerInterface *iface);
  74
  75 G_DEFINE_TYPE_WITH_CODE (Seat, seat, G_TYPE_OBJECT,
  76                          G_IMPLEMENT_INTERFACE (
  77                              LOGGER_TYPE, seat_logger_iface_init));
  78
  79 typedef struct
  80 {
  81     gchar *name;
  82     GType type;
  83 } SeatModule;
  84 static GHashTable *seat_modules = NULL;
  85
  86 // FIXME: Make a get_display_server() that re-uses display servers if supported
  87 static DisplayServer *create_display_server (Seat *seat, Session *session);
  88 static gboolean start_display_server (Seat *seat, DisplayServer *display_server);
  89 static GreeterSession *create_greeter_session (Seat *seat);
  90 static void start_session (Seat *seat, Session *session);
  91
  92 static void
  93 free_seat_module (gpointer data)
  94 {
  95     SeatModule *module = data;
  96     g_free (module->name);
  97     g_free (module);
  98 }
  99
 100 void
 101 seat_register_module (const gchar *name, GType type)
 102 {
 103     SeatModule *module;
 104
 105     if (!seat_modules)
 106         seat_modules = g_hash_table_new_full (g_str_hash, g_str_equal, free_seat_module, NULL);
 107
 108     g_debug ("Registered seat module %s", name);
 109
 110     module = g_malloc0 (sizeof (SeatModule));
 111     module->name = g_strdup (name);
 112     module->type = type;
 113     g_hash_table_insert (seat_modules, g_strdup (name), module);
 114 }
 115
 116 Seat *
 117 seat_new (const gchar *module_name, const gchar *name)
 118 {
 119     Seat *seat;
 120     SeatModule *m = NULL;
 121
 122     g_return_val_if_fail (module_name != NULL, NULL);
 123
 124     if (seat_modules)
 125         m = g_hash_table_lookup (seat_modules, module_name);
 126     if (!m)
 127         return NULL;
 128
 129     seat = g_object_new (m->type, NULL);
 130     seat->priv->name = g_strdup (name);
 131
 132     return seat;
 133 }
 134
 135 void
 136 seat_set_property (Seat *seat, const gchar *name, const gchar *value)
 137 {
 138     g_return_if_fail (seat != NULL);
 139     g_hash_table_insert (seat->priv->properties, g_strdup (name), g_strdup (value));
 140 }
 141
 142 const gchar *
 143 seat_get_string_property (Seat *seat, const gchar *name)
 144 {
 145     g_return_val_if_fail (seat != NULL, NULL);
 146     return g_hash_table_lookup (seat->priv->properties, name);
 147 }
 148
 149 gchar **
 150 seat_get_string_list_property (Seat *seat, const gchar *name)
 151 {
 152     g_return_val_if_fail (seat != NULL, NULL);
 153     return g_strsplit (g_hash_table_lookup (seat->priv->properties, name), ";", 0);
 154 }
 155
 156 gboolean
 157 seat_get_boolean_property (Seat *seat, const gchar *name)
 158 {
 159     const gchar *value;
 160     gint i, length = 0;
 161
 162     value = seat_get_string_property (seat, name);
 163     if (!value)
 164         return FALSE;
 165
 166     /* Count the number of non-whitespace characters */
 167     for (i = 0; value[i]; i++)
 168         if (!g_ascii_isspace (value[i]))
 169             length = i + 1;
 170
 171     return strncmp (value, "true", MAX (length, 4)) == 0;
 172 }
 173
 174 gint
 175 seat_get_integer_property (Seat *seat, const gchar *name)
 176 {
 177     const gchar *value;
 178
 179     value = seat_get_string_property (seat, name);
 180     return value ? atoi (value) : 0;
 181 }
 182
 183 const gchar *
 184 seat_get_name (Seat *seat)
 185 {
 186     return seat->priv->name;
 187 }
 188
 189 void
 190 seat_set_supports_multi_session (Seat *seat, gboolean supports_multi_session)
 191 {
 192     g_return_if_fail (seat != NULL);
 193     seat->priv->supports_multi_session = supports_multi_session;
 194 }
 195
 196 void
 197 seat_set_share_display_server (Seat *seat, gboolean share_display_server)
 198 {
 199     g_return_if_fail (seat != NULL);
 200     seat->priv->share_display_server = share_display_server;
 201 }
 202
 203 gboolean
 204 seat_start (Seat *seat)
 205 {
 206     g_return_val_if_fail (seat != NULL, FALSE);
 207
 208     l_debug (seat, "Starting");
 209
 210     SEAT_GET_CLASS (seat)->setup (seat);
 211     seat->priv->started = SEAT_GET_CLASS (seat)->start (seat);
 212
 213     return seat->priv->started;
 214 }
 215
 216 GList *
 217 seat_get_sessions (Seat *seat)
 218 {
 219     g_return_val_if_fail (seat != NULL, NULL);
 220     return seat->priv->sessions;
 221 }
 222
 223 static gboolean
 224 set_greeter_idle (gpointer greeter)
 225 {
 226     greeter_idle (GREETER (greeter));
 227     return FALSE;
 228 }
 229
 230 void
 231 seat_set_active_session (Seat *seat, Session *session)
 232 {
 233     GList *link;
 234
 235     g_return_if_fail (seat != NULL);
 236
 237     SEAT_GET_CLASS (seat)->set_active_session (seat, session);
 238
 239     /* Stop any greeters */
 240     for (link = seat->priv->sessions; link; link = link->next)
 241     {
 242         Session *s = link->data;
 243
 244         if (s == session || session_get_is_stopping (s))
 245             continue;
 246
 247         if (IS_GREETER_SESSION (s))
 248         {
 249             Greeter *greeter = greeter_session_get_greeter (GREETER_SESSION (s));
 250             if (greeter_get_resettable (greeter))
 251             {
 252                 if (seat->priv->active_session == s)
 253                 {
 254                     l_debug (seat, "Idling greeter");
 255                     /* Do this in an idle callback, because we might very well
 256                        be in the middle of responding to a START_SESSION
 257                        request by a greeter.  So they won't expect an IDLE
 258                        call during that.  Plus, this isn't time-sensitive. */
 259                     g_idle_add (set_greeter_idle, greeter);
 260                 }
 261             }
 262             else
 263             {
 264                 l_debug (seat, "Stopping greeter");
 265                 session_stop (s);
 266             }
 267         }
 268     }
 269
 270     /* Lock previous sessions */
 271     if (seat->priv->active_session && session != seat->priv->active_session && !IS_GREETER_SESSION (seat->priv->active_session))
 272         session_lock (seat->priv->active_session);
 273
 274     session_activate (session);
 275     g_clear_object (&seat->priv->active_session);
 276     seat->priv->active_session = g_object_ref (session);
 277 }
 278
 279 Session *
 280 seat_get_active_session (Seat *seat)
 281 {
 282     g_return_val_if_fail (seat != NULL, NULL);
 283     return SEAT_GET_CLASS (seat)->get_active_session (seat);
 284 }
 285
 286 Session *
 287 seat_get_next_session (Seat *seat)
 288 {
 289     g_return_val_if_fail (seat != NULL, NULL);
 290     return seat->priv->next_session;
 291 }
 292
 293 /**
 294  * Obtains the active session which lightdm expects to be active.
 295  *
 296  * This function is different from seat_get_active_session() in that the
 297  * later (in the case of local seats) dynamically finds the session that is
 298  * really active (based on the active VT), whereas this function returns the
 299  * session that lightdm activated last by itself, which may not be the actual
 300  * active session (i.e. VT changes).
 301  */
 302 Session *
 303 seat_get_expected_active_session (Seat *seat)
 304 {
 305     g_return_val_if_fail (seat != NULL, NULL);
 306     return seat->priv->active_session;
 307 }
 308
 309 /**
 310  * Sets the active session which lightdm expects to be active.
 311  *
 312  * This function is different from seat_set_active_session() in that the
 313  * later performs an actual session activation, whereas this function just
 314  * updates the active session after the session has been activated by some
 315  * means external to lightdm (i.e. VT changes).
 316  */
 317 void
 318 seat_set_externally_activated_session (Seat *seat, Session *session)
 319 {
 320     g_return_if_fail (seat != NULL);
 321     g_clear_object (&seat->priv->active_session);
 322     seat->priv->active_session = g_object_ref (session);
 323 }
 324
 325 Session *
 326 seat_find_session_by_login1_id (Seat *seat, const gchar *login1_session_id)
 327 {
 328     GList *session_link;
 329
 330     for (session_link = seat->priv->sessions; session_link; session_link = session_link->next)
 331     {
 332         Session *session = session_link->data;
 333         if (g_strcmp0 (login1_session_id, session_get_login1_session_id (session)) == 0)
 334             return session;
 335     }
 336
 337     return NULL;
 338 }
 339
 340 gboolean
 341 seat_get_can_switch (Seat *seat)
 342 {
 343     g_return_val_if_fail (seat != NULL, FALSE);
 344     return seat_get_boolean_property (seat, "allow-user-switching") && seat->priv->supports_multi_session;
 345 }
 346
 347 gboolean
 348 seat_get_allow_guest (Seat *seat)
 349 {
 350     g_return_val_if_fail (seat != NULL, FALSE);
 351     return seat_get_boolean_property (seat, "allow-guest") && guest_account_is_installed ();
 352 }
 353
 354 static gboolean
 355 run_script (Seat *seat, DisplayServer *display_server, const gchar *script_name, User *user)
 356 {
 357     Process *script;
 358     gboolean result = FALSE;
 359
 360     script = process_new (NULL, NULL);
 361
 362     process_set_command (script, script_name);
 363
 364     /* Set POSIX variables */
 365     process_set_clear_environment (script, TRUE);
 366     process_set_env (script, "SHELL", "/bin/sh");
 367
 368     /* Variables required for regression tests */
 369     if (g_getenv ("LIGHTDM_TEST_ROOT"))
 370     {
 371         process_set_env (script, "LIGHTDM_TEST_ROOT", g_getenv ("LIGHTDM_TEST_ROOT"));
 372         process_set_env (script, "LD_PRELOAD", g_getenv ("LD_PRELOAD"));
 373         process_set_env (script, "LD_LIBRARY_PATH", g_getenv ("LD_LIBRARY_PATH"));
 374         process_set_env (script, "PATH", g_getenv ("PATH"));
 375     }
 376     else
 377         process_set_env (script, "PATH", "/usr/local/bin:/usr/bin:/bin");
 378
 379     if (user)
 380     {
 381         process_set_env (script, "USER", user_get_name (user));
 382         process_set_env (script, "LOGNAME", user_get_name (user));
 383         process_set_env (script, "HOME", user_get_home_directory (user));
 384     }
 385     else
 386         process_set_env (script, "HOME", "/");
 387
 388     SEAT_GET_CLASS (seat)->run_script (seat, display_server, script);
 389
 390     if (process_start (script, TRUE))
 391     {
 392         int exit_status;
 393
 394         exit_status = process_get_exit_status (script);
 395         if (WIFEXITED (exit_status))
 396         {
 397             l_debug (seat, "Exit status of %s: %d", script_name, WEXITSTATUS (exit_status));
 398             result = WEXITSTATUS (exit_status) == EXIT_SUCCESS;
 399         }
 400     }
 401
 402     g_object_unref (script);
 403
 404     return result;
 405 }
 406
 407 static void
 408 seat_real_run_script (Seat *seat, DisplayServer *display_server, Process *process)
 409 {
 410 }
 411
 412 static void
 413 emit_upstart_signal (const gchar *signal)
 414 {
 415     g_return_if_fail (signal != NULL);
 416     g_return_if_fail (signal[0] != 0);
 417     GSubprocess *p;
 418
 419     if (getuid () != 0)
 420         return;
 421
 422     /* OK if it fails, probably not installed or not running upstart */
 423     p = g_subprocess_new (G_SUBPROCESS_FLAGS_STDERR_SILENCE, NULL, "initctl", "-q", "emit", signal, "DISPLAY_MANAGER=lightdm", NULL);
 424     g_object_unref (p);
 425 }
 426
 427 static void
 428 check_stopped (Seat *seat)
 429 {
 430     if (seat->priv->stopping &&
 431         !seat->priv->stopped &&
 432         g_list_length (seat->priv->display_servers) == 0 &&
 433         g_list_length (seat->priv->sessions) == 0)
 434     {
 435         seat->priv->stopped = TRUE;
 436         l_debug (seat, "Stopped");
 437         g_signal_emit (seat, signals[STOPPED], 0);
 438     }
 439 }
 440
 441 static void
 442 display_server_stopped_cb (DisplayServer *display_server, Seat *seat)
 443 {
 444     const gchar *script;
 445     GList *list, *link;
 446     Session *active_session;
 447
 448     l_debug (seat, "Display server stopped");
 449
 450     /* Run a script right after stopping the display server */
 451     script = seat_get_string_property (seat, "display-stopped-script");
 452     if (script)
 453         run_script (seat, NULL, script, NULL);
 454
 455     g_signal_handlers_disconnect_matched (display_server, G_SIGNAL_MATCH_DATA, 0, 0, NULL, NULL, seat);
 456     seat->priv->display_servers = g_list_remove (seat->priv->display_servers, display_server);
 457
 458     if (seat->priv->stopping || !seat->priv->started)
 459     {
 460         check_stopped (seat);
 461         g_object_unref (display_server);
 462         return;
 463     }
 464
 465     /* Stop all sessions on this display server */
 466     list = g_list_copy (seat->priv->sessions);
 467     for (link = list; link; link = link->next)
 468         g_object_ref (link->data);
 469     for (link = list; link; link = link->next)
 470     {
 471         Session *session = link->data;
 472
 473         if (session_get_display_server (session) != display_server || session_get_is_stopping (session))
 474             continue;
 475
 476         /* Stop seat if this is the only display server and it failed to start a greeter */
 477         if (IS_GREETER_SESSION (session) &&
 478             !session_get_is_started (session) &&
 479             g_list_length (seat->priv->display_servers) == 0)
 480         {
 481             l_debug (seat, "Stopping; greeter display server failed to start");
 482             seat_stop (seat);
 483         }
 484
 485         l_debug (seat, "Stopping session");
 486         session_stop (session);
 487     }
 488     g_list_free_full (list, g_object_unref);
 489
 490     if (!seat->priv->stopping)
 491     {
 492         /* If we were the active session, switch to a greeter */
 493         active_session = seat_get_active_session (seat);
 494         if (!active_session || session_get_display_server (active_session) == display_server)
 495         {
 496             l_debug (seat, "Active display server stopped, starting greeter");
 497             if (!seat_switch_to_greeter (seat))
 498             {
 499                 l_debug (seat, "Stopping; failed to start a greeter");
 500                 seat_stop (seat);
 501             }
 502         }
 503     }
 504
 505     g_object_unref (display_server);
 506 }
 507
 508 static gboolean
 509 can_share_display_server (Seat *seat, DisplayServer *display_server)
 510 {
 511     return seat->priv->share_display_server && display_server_get_can_share (display_server);
 512 }
 513
 514 static GreeterSession *
 515 find_greeter_session (Seat *seat)
 516 {
 517     GList *link;
 518
 519     for (link = seat->priv->sessions; link; link = link->next)
 520     {
 521         Session *session = link->data;
 522         if (!session_get_is_stopping (session) && IS_GREETER_SESSION (session))
 523             return GREETER_SESSION (session);
 524     }
 525
 526     return NULL;
 527 }
 528
 529 static GreeterSession *
 530 find_resettable_greeter (Seat *seat)
 531 {
 532     GList *link;
 533
 534     for (link = seat->priv->sessions; link; link = link->next)
 535     {
 536         Session *session = link->data;
 537         if (!session_get_is_stopping (session) && IS_GREETER_SESSION (session) &&
 538             greeter_get_resettable (greeter_session_get_greeter (GREETER_SESSION (session))))
 539             return GREETER_SESSION (session);
 540     }
 541
 542     return NULL;
 543 }
 544
 545 static void
 546 set_greeter_hints (Seat *seat, Greeter *greeter)
 547 {
 548     greeter_clear_hints (greeter);
 549     greeter_set_hint (greeter, "default-session", seat_get_string_property (seat, "user-session"));
 550     greeter_set_hint (greeter, "hide-users", seat_get_boolean_property (seat, "greeter-hide-users") ? "true" : "false");
 551     greeter_set_hint (greeter, "show-manual-login", seat_get_boolean_property (seat, "greeter-show-manual-login") ? "true" : "false");
 552     greeter_set_hint (greeter, "show-remote-login", seat_get_boolean_property (seat, "greeter-show-remote-login") ? "true" : "false");
 553     greeter_set_hint (greeter, "has-guest-account", seat_get_allow_guest (seat) && seat_get_boolean_property (seat, "greeter-allow-guest") ? "true" : "false");
 554 }
 555
 556 static void
 557 switch_to_greeter_from_failed_session (Seat *seat, Session *session)
 558 {
 559     GreeterSession *greeter_session;
 560     Greeter *greeter;
 561     gboolean existing = FALSE;
 562
 563     /* Switch to greeter if one open */
 564     greeter_session = find_resettable_greeter (seat);
 565     if (greeter_session)
 566     {
 567         l_debug (seat, "Switching to existing greeter");
 568         set_greeter_hints (seat, greeter_session_get_greeter (greeter_session));
 569         existing = TRUE;
 570     }
 571     else
 572     {
 573         greeter_session = create_greeter_session (seat);
 574     }
 575     greeter = greeter_session_get_greeter (greeter_session);
 576
 577     if (session_get_is_guest (session))
 578         greeter_set_hint (greeter, "select-guest", "true");
 579     else
 580         greeter_set_hint (greeter, "select-user", session_get_username (session));
 581
 582     if (existing)
 583     {
 584         greeter_reset (greeter);
 585         seat_set_active_session (seat, SESSION (greeter_session));
 586     }
 587     else
 588     {
 589         g_clear_object (&seat->priv->session_to_activate);
 590         seat->priv->session_to_activate = g_object_ref (greeter_session);
 591
 592         if (can_share_display_server (seat, session_get_display_server (session)))
 593             session_set_display_server (SESSION (greeter_session), session_get_display_server (session));
 594         else
 595         {
 596             DisplayServer *display_server;
 597
 598             display_server = create_display_server (seat, session);
 599             session_set_display_server (session, display_server);
 600             if (!start_display_server (seat, display_server))
 601             {
 602                 l_debug (seat, "Failed to start display server for greeter");
 603                 seat_stop (seat);
 604             }
 605         }
 606
 607         start_session (seat, SESSION (greeter_session));
 608     }
 609
 610     /* Stop failed session */
 611     session_stop (session);
 612 }
 613
 614 static void
 615 start_session (Seat *seat, Session *session)
 616 {
 617     /* Use system location for greeter log file */
 618     if (IS_GREETER_SESSION (session))
 619     {
 620         gchar *log_dir, *filename, *log_filename;
 621         gboolean backup_logs;
 622
 623         log_dir = config_get_string (config_get_instance (), "LightDM", "log-directory");
 624         filename = g_strdup_printf ("%s-greeter.log", seat->priv->name);
 625         log_filename = g_build_filename (log_dir, filename, NULL);
 626         g_free (log_dir);
 627         g_free (filename);
 628         backup_logs = config_get_boolean (config_get_instance (), "LightDM", "backup-logs");
 629         session_set_log_file (session, log_filename, backup_logs ? LOG_MODE_BACKUP_AND_TRUNCATE : LOG_MODE_APPEND);
 630         g_free (log_filename);
 631     }
 632
 633     if (session_start (session))
 634         return;
 635
 636     if (IS_GREETER_SESSION (session))
 637     {
 638         l_debug (seat, "Failed to start greeter");
 639         display_server_stop (session_get_display_server (session));
 640         return;
 641     }
 642
 643     l_debug (seat, "Failed to start session, starting greeter");
 644     switch_to_greeter_from_failed_session (seat, session);
 645 }
 646
 647 static void
 648 run_session (Seat *seat, Session *session)
 649 {
 650     const gchar *script;
 651
 652     if (IS_GREETER_SESSION (session))
 653         script = seat_get_string_property (seat, "greeter-setup-script");
 654     else
 655         script = seat_get_string_property (seat, "session-setup-script");
 656     if (script && !run_script (seat, session_get_display_server (session), script, session_get_user (session)))
 657     {
 658         l_debug (seat, "Switching to greeter due to failed setup script");
 659         switch_to_greeter_from_failed_session (seat, session);
 660         return;
 661     }
 662
 663     if (!IS_GREETER_SESSION (session))
 664     {
 665         g_signal_emit (seat, signals[RUNNING_USER_SESSION], 0, session);
 666         emit_upstart_signal ("desktop-session-start");
 667     }
 668
 669     session_run (session);
 670
 671     // FIXME: Wait until the session is ready
 672
 673     if (session == seat->priv->session_to_activate)
 674     {
 675         seat_set_active_session (seat, session);
 676         g_clear_object (&seat->priv->session_to_activate);
 677     }
 678     else if (seat->priv->active_session)
 679     {
 680         /* Multiple sessions can theoretically be on the same VT (especially
 681            if using Mir).  If a new session appears on an existing active VT,
 682            logind will mark it as active, while ConsoleKit will re-mark the
 683            oldest session as active.  In either case, that may not be the
 684            session that we want to be active.  So let's be explicit and
 685            re-activate the correct session whenever a new session starts.
 686            There's no harm to do this in seats that enforce separate VTs. */
 687         session_activate (seat->priv->active_session);
 688     }
 689 }
 690
 691 static Session *
 692 find_user_session (Seat *seat, const gchar *username, Session *ignore_session)
 693 {
 694     GList *link;
 695
 696     if (!username)
 697         return NULL;
 698
 699     for (link = seat->priv->sessions; link; link = link->next)
 700     {
 701         Session *session = link->data;
 702
 703         if (session == ignore_session)
 704             continue;
 705
 706         if (!session_get_is_stopping (session) && g_strcmp0 (session_get_username (session), username) == 0)
 707             return session;
 708     }
 709
 710     return NULL;
 711 }
 712
 713 static void
 714 greeter_active_username_changed_cb (Greeter *greeter, GParamSpec *pspec, Seat *seat)
 715 {
 716     Session *session;
 717
 718     session = find_user_session (seat, greeter_get_active_username (greeter), seat->priv->active_session);
 719
 720     g_clear_object (&seat->priv->next_session);
 721     seat->priv->next_session = session ? g_object_ref (session) : NULL;
 722
 723     SEAT_GET_CLASS (seat)->set_next_session (seat, session);
 724 }
 725
 726 static void
 727 session_authentication_complete_cb (Session *session, Seat *seat)
 728 {
 729     if (session_get_is_authenticated (session))
 730     {
 731         Session *s;
 732
 733         s = find_user_session (seat, session_get_username (session), session);
 734         if (s)
 735         {
 736             l_debug (seat, "Session authenticated, switching to existing user session");
 737             seat_set_active_session (seat, s);
 738             session_stop (session);
 739         }
 740         else
 741         {
 742             l_debug (seat, "Session authenticated, running command");
 743             run_session (seat, session);
 744         }
 745     }
 746     else if (!IS_GREETER_SESSION (session))
 747     {
 748         l_debug (seat, "Switching to greeter due to failed authentication");
 749         switch_to_greeter_from_failed_session (seat, session);
 750     }
 751     else
 752     {
 753         l_debug (seat, "Stopping session that failed authentication");
 754         session_stop (session);
 755     }
 756 }
 757
 758 static void
 759 session_stopped_cb (Session *session, Seat *seat)
 760 {
 761     DisplayServer *display_server;
 762
 763     l_debug (seat, "Session stopped");
 764
 765     g_signal_handlers_disconnect_matched (session, G_SIGNAL_MATCH_DATA, 0, 0, NULL, NULL, seat);
 766     seat->priv->sessions = g_list_remove (seat->priv->sessions, session);
 767     if (session == seat->priv->active_session)
 768         g_clear_object (&seat->priv->active_session);
 769     if (session == seat->priv->next_session)
 770         g_clear_object (&seat->priv->next_session);
 771     if (session == seat->priv->session_to_activate)
 772         g_clear_object (&seat->priv->session_to_activate);
 773
 774     display_server = session_get_display_server (session);
 775     if (!display_server)
 776     {
 777         g_object_unref (session);
 778         return;
 779     }
 780
 781     /* Cleanup */
 782     if (!IS_GREETER_SESSION (session))
 783     {
 784         const gchar *script;
 785         script = seat_get_string_property (seat, "session-cleanup-script");
 786         if (script)
 787             run_script (seat, display_server, script, session_get_user (session));
 788     }
 789
 790     /* We were waiting for this session, but it didn't start :( */
 791     // FIXME: Start a greeter on this?
 792     if (session == seat->priv->session_to_activate)
 793         g_clear_object (&seat->priv->session_to_activate);
 794
 795     if (seat->priv->stopping)
 796     {
 797         check_stopped (seat);
 798         g_object_unref (session);
 799         return;
 800     }
 801
 802     /* If there is a pending replacement greeter, start it */
 803     if (IS_GREETER_SESSION (session) && seat->priv->replacement_greeter)
 804     {
 805         GreeterSession *replacement_greeter = seat->priv->replacement_greeter;
 806         seat->priv->replacement_greeter = NULL;
 807
 808         if (session_get_is_authenticated (SESSION (replacement_greeter)))
 809         {
 810             l_debug (seat, "Greeter stopped, running session");
 811             run_session (seat, SESSION (replacement_greeter));
 812         }
 813         else
 814         {
 815             l_debug (seat, "Greeter stopped, starting session authentication");
 816             start_session (seat, SESSION (replacement_greeter));
 817         }
 818
 819         g_object_unref (replacement_greeter);
 820     }
 821     /* If this is the greeter session then re-use this display server */
 822     else if (IS_GREETER_SESSION (session) &&
 823         can_share_display_server (seat, display_server) &&
 824         greeter_get_start_session (greeter_session_get_greeter (GREETER_SESSION (session))))
 825     {
 826         GList *link;
 827
 828         for (link = seat->priv->sessions; link; link = link->next)
 829         {
 830             Session *s = link->data;
 831
 832             /* Skip this session and sessions on other display servers */
 833             if (s == session || session_get_display_server (s) != display_server || session_get_is_stopping (s))
 834                 continue;
 835
 836             if (session_get_is_authenticated (s))
 837             {
 838                 l_debug (seat, "Greeter stopped, running session");
 839                 run_session (seat, s);
 840             }
 841             else
 842             {
 843                 l_debug (seat, "Greeter stopped, starting session authentication");
 844                 start_session (seat, s);
 845             }
 846             break;
 847         }
 848     }
 849     /* If this is the greeter and nothing else is running then stop the seat */
 850     else if (IS_GREETER_SESSION (session) &&
 851         !greeter_get_start_session (greeter_session_get_greeter (GREETER_SESSION (session))) &&
 852         g_list_length (seat->priv->display_servers) == 1 &&
 853         g_list_nth_data (seat->priv->display_servers, 0) == display_server)
 854     {
 855         l_debug (seat, "Stopping; failed to start a greeter");
 856         seat_stop (seat);
 857     }
 858     /* If we were the active session, switch to a greeter */
 859     else if (!IS_GREETER_SESSION (session) && session == seat_get_active_session (seat))
 860     {
 861         l_debug (seat, "Active session stopped, starting greeter");
 862         if (!seat_switch_to_greeter (seat))
 863         {
 864             l_debug (seat, "Stopping; failed to start a greeter");
 865             seat_stop (seat);
 866         }
 867     }
 868
 869     /* Stop the display server if no-longer required */
 870     if (display_server && !display_server_get_is_stopping (display_server) &&
 871         !SEAT_GET_CLASS (seat)->display_server_is_used (seat, display_server))
 872     {
 873         l_debug (seat, "Stopping display server, no sessions require it");
 874         display_server_stop (display_server);
 875     }
 876
 877     g_signal_emit (seat, signals[SESSION_REMOVED], 0, session);
 878     g_object_unref (session);
 879 }
 880
 881 static void
 882 set_session_env (Session *session)
 883 {
 884     /* Connect using the session bus */
 885     if (getuid () != 0)
 886     {
 887         if (g_getenv ("DBUS_SESSION_BUS_ADDRESS"))
 888             session_set_env (session, "DBUS_SESSION_BUS_ADDRESS", g_getenv ("DBUS_SESSION_BUS_ADDRESS"));
 889         session_set_env (session, "LDM_BUS", "SESSION");
 890         if (g_getenv ("LD_PRELOAD"))
 891             session_set_env (session, "LD_PRELOAD", g_getenv ("LD_PRELOAD"));
 892         if (g_getenv ("LD_LIBRARY_PATH"))
 893             session_set_env (session, "LD_LIBRARY_PATH", g_getenv ("LD_LIBRARY_PATH"));
 894         if (g_getenv ("PATH"))
 895             session_set_env (session, "PATH", g_getenv ("PATH"));
 896     }
 897
 898     /* Variables required for regression tests */
 899     if (g_getenv ("LIGHTDM_TEST_ROOT"))
 900     {
 901         session_set_env (session, "LIGHTDM_TEST_ROOT", g_getenv ("LIGHTDM_TEST_ROOT"));
 902         session_set_env (session, "DBUS_SYSTEM_BUS_ADDRESS", g_getenv ("DBUS_SYSTEM_BUS_ADDRESS"));
 903         session_set_env (session, "DBUS_SESSION_BUS_ADDRESS", g_getenv ("DBUS_SESSION_BUS_ADDRESS"));
 904         session_set_env (session, "LD_PRELOAD", g_getenv ("LD_PRELOAD"));
 905         session_set_env (session, "LD_LIBRARY_PATH", g_getenv ("LD_LIBRARY_PATH"));
 906         session_set_env (session, "GI_TYPELIB_PATH", g_getenv ("GI_TYPELIB_PATH"));
 907     }
 908 }
 909
 910 static Session *
 911 create_session (Seat *seat, gboolean autostart)
 912 {
 913     Session *session;
 914
 915     session = SEAT_GET_CLASS (seat)->create_session (seat);
 916     seat->priv->sessions = g_list_append (seat->priv->sessions, session);
 917     if (autostart)
 918         g_signal_connect (session, SESSION_SIGNAL_AUTHENTICATION_COMPLETE, G_CALLBACK (session_authentication_complete_cb), seat);
 919     g_signal_connect (session, SESSION_SIGNAL_STOPPED, G_CALLBACK (session_stopped_cb), seat);
 920
 921     set_session_env (session);
 922
 923     g_signal_emit (seat, signals[SESSION_ADDED], 0, session);
 924
 925     return session;
 926 }
 927
 928 static gchar **
 929 get_session_argv (Seat *seat, SessionConfig *session_config, const gchar *session_wrapper)
 930 {
 931     gboolean result;
 932     int argc;
 933     gchar **argv, *path;
 934     GError *error = NULL;
 935
 936     /* If configured, run sessions through a wrapper */
 937     if (session_wrapper)
 938     {
 939         argv = g_malloc (sizeof (gchar *) * 3);
 940         path = g_find_program_in_path (session_wrapper);
 941         argv[0] = path ? path : g_strdup (session_wrapper);
 942         argv[1] = g_strdup (session_config_get_command (session_config));
 943         argv[2] = NULL;
 944         return argv;
 945     }
 946
 947     /* Split command into an array listing and make command absolute */
 948     result = g_shell_parse_argv (session_config_get_command (session_config), &argc, &argv, &error);
 949     if (error)
 950         l_debug (seat, "Invalid session command '%s': %s", session_config_get_command (session_config), error->message);
 951     g_clear_error (&error);
 952     if (!result)
 953         return NULL;
 954     path = g_find_program_in_path (argv[0]);
 955     if (path)
 956     {
 957         g_free (argv[0]);
 958         argv[0] = path;
 959     }
 960
 961     return argv;
 962 }
 963
 964 static SessionConfig *
 965 find_session_config (Seat *seat, const gchar *sessions_dir, const gchar *session_name)
 966 {
 967     gchar **dirs;
 968     SessionConfig *session_config = NULL;
 969     int i;
 970     GError *error = NULL;
 971
 972     g_return_val_if_fail (sessions_dir != NULL, NULL);
 973     g_return_val_if_fail (session_name != NULL, NULL);
 974
 975     dirs = g_strsplit (sessions_dir, ":", -1);
 976     for (i = 0; dirs[i]; i++)
 977     {
 978         gchar *filename, *path;
 979         const gchar *default_session_type = "x";
 980
 981         if (strcmp (dirs[i], WAYLAND_SESSIONS_DIR) == 0)
 982             default_session_type = "wayland";
 983
 984         filename = g_strdup_printf ("%s.desktop", session_name);
 985         path = g_build_filename (dirs[i], filename, NULL);
 986         g_free (filename);
 987         session_config = session_config_new_from_file (path, default_session_type, &error);
 988         g_free (path);
 989         if (session_config)
 990             break;
 991
 992         if (dirs[i+1] == NULL)
 993             l_debug (seat, "Failed to find session configuration %s", session_name);
 994         g_clear_error (&error);
 995     }
 996     g_strfreev (dirs);
 997
 998     return session_config;
 999 }
1000
1001 static void
1002 configure_session (Session *session, SessionConfig *config, const gchar *session_name, const gchar *language)
1003 {
1004     gchar **desktop_names;
1005
1006     session_set_config (session, config);
1007     session_set_env (session, "XDG_SESSION_DESKTOP", session_name);
1008     session_set_env (session, "DESKTOP_SESSION", session_name);
1009     session_set_env (session, "GDMSESSION", session_name);
1010     desktop_names = session_config_get_desktop_names (config);
1011     if (desktop_names)
1012     {
1013         gchar *value;
1014         value = g_strjoinv (":", desktop_names);
1015         session_set_env (session, "XDG_CURRENT_DESKTOP", value);
1016         g_free (value);
1017     }
1018     if (language && language[0] != '\0')
1019     {
1020         session_set_env (session, "LANG", language);
1021         session_set_env (session, "GDM_LANG", language);
1022     }
1023 }
1024
1025 static Session *
1026 create_user_session (Seat *seat, const gchar *username, gboolean autostart)
1027 {
1028     User *user;
1029     gchar *sessions_dir;
1030     const gchar *session_name, *language;
1031     SessionConfig *session_config;
1032     Session *session = NULL;
1033
1034     l_debug (seat, "Creating user session");
1035
1036     /* Load user preferences */
1037     user = accounts_get_user_by_name (username);
1038     if (!user)
1039     {
1040         l_debug (seat, "Can't login unknown user '%s'", username);
1041         return NULL;
1042     }
1043     session_name = user_get_xsession (user);
1044     language = user_get_language (user);
1045
1046     /* Override session for autologin if configured */
1047     if (autostart)
1048     {
1049         const gchar *autologin_session_name = seat_get_string_property (seat, "autologin-session");
1050         if (autologin_session_name)
1051             session_name = autologin_session_name;
1052     }
1053
1054     if (!session_name)
1055         session_name = seat_get_string_property (seat, "user-session");
1056     sessions_dir = config_get_string (config_get_instance (), "LightDM", "sessions-directory");
1057     session_config = find_session_config (seat, sessions_dir, session_name);
1058     g_free (sessions_dir);
1059     if (session_config)
1060     {
1061         gchar **argv;
1062
1063         session = create_session (seat, autostart);
1064         configure_session (session, session_config, session_name, language);
1065         session_set_username (session, username);
1066         session_set_do_authenticate (session, TRUE);
1067         argv = get_session_argv (seat, session_config, seat_get_string_property (seat, "session-wrapper"));
1068         session_set_argv (session, argv);
1069         g_strfreev (argv);
1070         g_object_unref (session_config);
1071     }
1072     else
1073         l_debug (seat, "Can't find session '%s'", session_name);
1074
1075     g_object_unref (user);
1076
1077     return session;
1078 }
1079
1080 static void
1081 prepend_argv (gchar ***argv, const gchar *value)
1082 {
1083     gchar **old_argv, **new_argv;
1084     gint i;
1085
1086     old_argv = *argv;
1087     new_argv = g_malloc (sizeof (gchar *) * (g_strv_length (*argv) + 2));
1088     new_argv[0] = g_strdup (value);
1089     for (i = 0; old_argv[i]; i++)
1090         new_argv[i + 1] = old_argv[i];
1091     new_argv[i + 1] = NULL;
1092
1093     g_free (*argv);
1094     *argv = new_argv;
1095 }
1096
1097 static Session *
1098 create_guest_session (Seat *seat, const gchar *session_name)
1099 {
1100     const gchar *guest_wrapper;
1101     gchar *sessions_dir, **argv;
1102     SessionConfig *session_config;
1103     Session *session;
1104
1105     if (!session_name)
1106         session_name = seat_get_string_property (seat, "guest-session");
1107     if (!session_name)
1108         session_name = seat_get_string_property (seat, "user-session");
1109     sessions_dir = config_get_string (config_get_instance (), "LightDM", "sessions-directory");
1110     session_config = find_session_config (seat, sessions_dir, session_name);
1111     g_free (sessions_dir);
1112     if (!session_config)
1113     {
1114         l_debug (seat, "Can't find session '%s'", session_name);
1115         return NULL;
1116     }
1117
1118     session = create_session (seat, TRUE);
1119     configure_session (session, session_config, session_name, NULL);
1120     session_set_do_authenticate (session, TRUE);
1121     session_set_is_guest (session, TRUE);
1122     argv = get_session_argv (seat, session_config, seat_get_string_property (seat, "session-wrapper"));
1123     guest_wrapper = seat_get_string_property (seat, "guest-wrapper");
1124     if (guest_wrapper)
1125     {
1126         gchar *path;
1127         path = g_find_program_in_path (guest_wrapper);
1128         prepend_argv (&argv, path ? path : guest_wrapper);
1129         g_free (path);
1130     }
1131
1132     session_set_argv (session, argv);
1133     g_strfreev (argv);
1134     g_object_unref (session_config);
1135
1136     return session;
1137 }
1138
1139 // FIXME: This is inefficient and we already know the greeter session when we set the callbacks...
1140 static Session *
1141 get_greeter_session (Seat *seat, Greeter *greeter)
1142 {
1143     GList *link;
1144
1145     /* Stop any greeters */
1146     for (link = seat->priv->sessions; link; link = link->next)
1147     {
1148         Session *session = link->data;
1149
1150         if (IS_GREETER_SESSION (session) && greeter_session_get_greeter (GREETER_SESSION (session)))
1151             return session;
1152     }
1153
1154     return NULL;
1155 }
1156
1157 static Session *
1158 greeter_create_session_cb (Greeter *greeter, Seat *seat)
1159 {
1160     Session *greeter_session, *session;
1161
1162     greeter_session = get_greeter_session (seat, greeter);
1163     session = create_session (seat, FALSE);
1164     session_set_config (session, session_get_config (greeter_session));
1165     session_set_display_server (session, session_get_display_server (greeter_session));
1166
1167     return g_object_ref (session);
1168 }
1169
1170 static gboolean
1171 greeter_start_session_cb (Greeter *greeter, SessionType type, const gchar *session_name, Seat *seat)
1172 {
1173     Session *session, *existing_session, *greeter_session;
1174     const gchar *username;
1175     DisplayServer *display_server;
1176
1177     /* Get the session to use */
1178     if (greeter_get_guest_authenticated (greeter))
1179     {
1180         session = g_object_ref (create_guest_session (seat, session_name));
1181         if (!session)
1182             return FALSE;
1183         session_set_pam_service (session, seat_get_string_property (seat, "pam-autologin-service"));
1184     }
1185     else
1186     {
1187         const gchar *language = NULL;
1188         SessionConfig *session_config;
1189         User *user;
1190         gchar *sessions_dir = NULL;
1191         gchar **argv;
1192
1193         session = greeter_take_authentication_session (greeter);
1194
1195         /* Get session command to run */
1196         switch (type)
1197         {
1198         case SESSION_TYPE_LOCAL:
1199             sessions_dir = config_get_string (config_get_instance (), "LightDM", "sessions-directory");
1200             break;
1201         case SESSION_TYPE_REMOTE:
1202             sessions_dir = config_get_string (config_get_instance (), "LightDM", "remote-sessions-directory");
1203             break;
1204         }
1205
1206         /* Load user preferences */
1207         user = session_get_user (session);
1208         if (user)
1209         {
1210             if (!session_name)
1211                 session_name = user_get_xsession (user);
1212             language = user_get_language (user);
1213         }
1214
1215         if (!session_name)
1216             session_name = seat_get_string_property (seat, "user-session");
1217         if (user)
1218             user_set_xsession (session_get_user (session), session_name);
1219
1220         session_config = find_session_config (seat, sessions_dir, session_name);
1221         g_free (sessions_dir);
1222         if (!session_config)
1223         {
1224             l_debug (seat, "Can't find session '%s'", session_name);
1225             return FALSE;
1226         }
1227
1228         configure_session (session, session_config, session_name, language);
1229         argv = get_session_argv (seat, session_config, seat_get_string_property (seat, "session-wrapper"));
1230         session_set_argv (session, argv);
1231         g_strfreev (argv);
1232         g_object_unref (session_config);
1233     }
1234
1235     /* Switch to this session when it is ready */
1236     g_clear_object (&seat->priv->session_to_activate);
1237     seat->priv->session_to_activate = session;
1238
1239     /* Return to existing session if it is open */
1240     username = session_get_username (session);
1241     existing_session = find_user_session (seat, username, NULL);
1242     if (existing_session && session != existing_session)
1243     {
1244         l_debug (seat, "Returning to existing user session %s", username);
1245         session_stop (session);
1246         session_unlock (existing_session);
1247         seat_set_active_session (seat, existing_session);
1248         return TRUE;
1249     }
1250
1251     /* If can re-use the display server, stop the greeter first */
1252     greeter_session = get_greeter_session (seat, greeter);
1253     if (greeter_session)
1254     {
1255         display_server = session_get_display_server (greeter_session);
1256         if (display_server &&
1257             !greeter_get_resettable (greeter) &&
1258             can_share_display_server (seat, display_server) &&
1259             strcmp (display_server_get_session_type (display_server), session_get_session_type (session)) == 0)
1260         {
1261             l_debug (seat, "Stopping greeter; display server will be re-used for user session");
1262
1263             /* Run on the same display server after the greeter has stopped */
1264             session_set_display_server (session, display_server);
1265
1266             /* Stop the greeter */
1267             session_stop (greeter_session);
1268
1269             return TRUE;
1270         }
1271     }
1272
1273     /* Otherwise start a new display server for this session */
1274     display_server = create_display_server (seat, session);
1275     session_set_display_server (session, display_server);
1276     if (!start_display_server (seat, display_server))
1277     {
1278         l_debug (seat, "Failed to start display server for new session");
1279         return FALSE;
1280     }
1281
1282     return TRUE;
1283 }
1284
1285 static GreeterSession *
1286 create_greeter_session (Seat *seat)
1287 {
1288     gchar *sessions_dir, **argv;
1289     SessionConfig *session_config;
1290     GreeterSession *greeter_session;
1291     Greeter *greeter;
1292     const gchar *greeter_wrapper;
1293     const gchar *autologin_username;
1294     int autologin_timeout;
1295     gboolean autologin_guest;
1296
1297     l_debug (seat, "Creating greeter session");
1298
1299     sessions_dir = config_get_string (config_get_instance (), "LightDM", "greeters-directory");
1300     session_config = find_session_config (seat, sessions_dir, seat_get_string_property (seat, "greeter-session"));
1301     g_free (sessions_dir);
1302     if (!session_config)
1303         return NULL;
1304
1305     argv = get_session_argv (seat, session_config, NULL);
1306     greeter_wrapper = seat_get_string_property (seat, "greeter-wrapper");
1307     if (greeter_wrapper)
1308     {
1309         gchar *path;
1310         path = g_find_program_in_path (greeter_wrapper);
1311         prepend_argv (&argv, path ? path : greeter_wrapper);
1312         g_free (path);
1313     }
1314
1315     greeter_session = SEAT_GET_CLASS (seat)->create_greeter_session (seat);
1316     greeter = greeter_session_get_greeter (greeter_session);
1317     session_set_config (SESSION (greeter_session), session_config);
1318     seat->priv->sessions = g_list_append (seat->priv->sessions, SESSION (greeter_session));
1319     g_signal_connect (greeter, GREETER_SIGNAL_ACTIVE_USERNAME_CHANGED, G_CALLBACK (greeter_active_username_changed_cb), seat);
1320     g_signal_connect (greeter_session, SESSION_SIGNAL_AUTHENTICATION_COMPLETE, G_CALLBACK (session_authentication_complete_cb), seat);
1321     g_signal_connect (greeter_session, SESSION_SIGNAL_STOPPED, G_CALLBACK (session_stopped_cb), seat);
1322
1323     set_session_env (SESSION (greeter_session));
1324     session_set_env (SESSION (greeter_session), "XDG_SESSION_CLASS", "greeter");
1325
1326     session_set_pam_service (SESSION (greeter_session), seat_get_string_property (seat, "pam-greeter-service"));
1327     if (getuid () == 0)
1328     {
1329         gchar *greeter_user;
1330         greeter_user = config_get_string (config_get_instance (), "LightDM", "greeter-user");
1331         session_set_username (SESSION (greeter_session), greeter_user);
1332         g_free (greeter_user);
1333     }
1334     else
1335     {
1336         /* In test mode run the greeter as ourself */
1337         session_set_username (SESSION (greeter_session), user_get_name (accounts_get_current_user ()));
1338     }
1339     session_set_argv (SESSION (greeter_session), argv);
1340     g_strfreev (argv);
1341
1342     greeter_set_pam_services (greeter,
1343                               seat_get_string_property (seat, "pam-service"),
1344                               seat_get_string_property (seat, "pam-autologin-service"));
1345     g_signal_connect (greeter, GREETER_SIGNAL_CREATE_SESSION, G_CALLBACK (greeter_create_session_cb), seat);
1346     g_signal_connect (greeter, GREETER_SIGNAL_START_SESSION, G_CALLBACK (greeter_start_session_cb), seat);
1347
1348     /* Set hints to greeter */
1349     greeter_set_allow_guest (greeter, seat_get_allow_guest (seat));
1350     set_greeter_hints (seat, greeter);
1351
1352     /* Configure for automatic login */
1353     autologin_username = seat_get_string_property (seat, "autologin-user");
1354     if (g_strcmp0 (autologin_username, "") == 0)
1355         autologin_username = NULL;
1356     autologin_timeout = seat_get_integer_property (seat, "autologin-user-timeout");
1357     autologin_guest = seat_get_boolean_property (seat, "autologin-guest");
1358     if (autologin_timeout > 0)
1359     {
1360         gchar *value;
1361
1362         value = g_strdup_printf ("%d", autologin_timeout);
1363         greeter_set_hint (greeter, "autologin-timeout", value);
1364         g_free (value);
1365         if (autologin_username)
1366             greeter_set_hint (greeter, "autologin-user", autologin_username);
1367         if (autologin_guest)
1368             greeter_set_hint (greeter, "autologin-guest", "true");
1369     }
1370
1371     g_object_unref (session_config);
1372
1373     return greeter_session;
1374 }
1375
1376 static Session *
1377 find_session_for_display_server (Seat *seat, DisplayServer *display_server)
1378 {
1379     GList *link;
1380
1381     for (link = seat->priv->sessions; link; link = link->next)
1382     {
1383         Session *session = link->data;
1384
1385         if (session_get_display_server (session) == display_server &&
1386             !session_get_is_stopping (session) &&
1387             !session_get_is_run (session))
1388             return session;
1389     }
1390
1391     return NULL;
1392 }
1393
1394 static void
1395 display_server_ready_cb (DisplayServer *display_server, Seat *seat)
1396 {
1397     const gchar *script;
1398     Session *session;
1399
1400     /* Run setup script */
1401     script = seat_get_string_property (seat, "display-setup-script");
1402     if (script && !run_script (seat, display_server, script, NULL))
1403     {
1404         l_debug (seat, "Stopping display server due to failed setup script");
1405         display_server_stop (display_server);
1406         return;
1407     }
1408
1409     emit_upstart_signal ("login-session-start");
1410
1411     /* Start the session waiting for this display server */
1412     session = find_session_for_display_server (seat, display_server);
1413     if (session)
1414     {
1415         if (session_get_is_authenticated (session))
1416         {
1417             l_debug (seat, "Display server ready, running session");
1418             run_session (seat, session);
1419         }
1420         else
1421         {
1422             l_debug (seat, "Display server ready, starting session authentication");
1423             start_session (seat, session);
1424         }
1425     }
1426     else
1427     {
1428         l_debug (seat, "Stopping not required display server");
1429         display_server_stop (display_server);
1430     }
1431 }
1432
1433 static DisplayServer *
1434 create_display_server (Seat *seat, Session *session)
1435 {
1436     DisplayServer *display_server;
1437
1438     l_debug (seat, "Creating display server of type %s", session_get_session_type (session));
1439
1440     display_server = SEAT_GET_CLASS (seat)->create_display_server (seat, session);
1441     if (!display_server)
1442         return NULL;
1443
1444     /* Remember this display server */
1445     if (!g_list_find (seat->priv->display_servers, display_server))
1446     {
1447         seat->priv->display_servers = g_list_append (seat->priv->display_servers, display_server);
1448         g_signal_connect (display_server, DISPLAY_SERVER_SIGNAL_READY, G_CALLBACK (display_server_ready_cb), seat);
1449         g_signal_connect (display_server, DISPLAY_SERVER_SIGNAL_STOPPED, G_CALLBACK (display_server_stopped_cb), seat);
1450     }
1451
1452     return display_server;
1453 }
1454
1455 static gboolean
1456 start_display_server (Seat *seat, DisplayServer *display_server)
1457 {
1458     if (display_server_get_is_ready (display_server))
1459     {
1460         display_server_ready_cb (display_server, seat);
1461         return TRUE;
1462     }
1463     else
1464         return display_server_start (display_server);
1465 }
1466
1467 gboolean
1468 seat_switch_to_greeter (Seat *seat)
1469 {
1470     GreeterSession *greeter_session;
1471     DisplayServer *display_server;
1472
1473     g_return_val_if_fail (seat != NULL, FALSE);
1474
1475     if (!seat_get_can_switch (seat))
1476         return FALSE;
1477
1478     /* Switch to greeter if one open */
1479     greeter_session = find_greeter_session (seat);
1480     if (greeter_session)
1481     {
1482         l_debug (seat, "Switching to existing greeter");
1483         seat_set_active_session (seat, SESSION (greeter_session));
1484         return TRUE;
1485     }
1486
1487     greeter_session = create_greeter_session (seat);
1488     if (!greeter_session)
1489         return FALSE;
1490
1491     g_clear_object (&seat->priv->session_to_activate);
1492     seat->priv->session_to_activate = g_object_ref (greeter_session);
1493
1494     display_server = create_display_server (seat, SESSION (greeter_session));
1495     session_set_display_server (SESSION (greeter_session), display_server);
1496
1497     return start_display_server (seat, display_server);
1498 }
1499
1500 static void
1501 switch_authentication_complete_cb (Session *session, Seat *seat)
1502 {
1503     GreeterSession *greeter_session;
1504     Greeter *greeter;
1505     DisplayServer *display_server;
1506     gboolean existing = FALSE;
1507
1508     /* If authenticated, then unlock existing session or start new one */
1509     if (session_get_is_authenticated (session))
1510     {
1511         Session *s;
1512
1513         s = find_user_session (seat, session_get_username (session), session);
1514         if (s)
1515         {
1516             l_debug (seat, "Session authenticated, switching to existing user session");
1517             session_unlock (s);
1518             seat_set_active_session (seat, s);
1519             session_stop (session);
1520         }
1521         else
1522         {
1523             l_debug (seat, "Session authenticated, starting display server");
1524             g_clear_object (&seat->priv->session_to_activate);
1525             seat->priv->session_to_activate = g_object_ref (session);
1526             display_server = create_display_server (seat, session);
1527             session_set_display_server (session, display_server);
1528             start_display_server (seat, display_server);
1529         }
1530
1531         return;
1532     }
1533
1534     session_stop (session);
1535
1536     /* See if we already have a greeter up and reuse it if so */
1537     greeter_session = find_resettable_greeter (seat);
1538     if (greeter_session)
1539     {
1540         l_debug (seat, "Switching to existing greeter to authenticate session");
1541         set_greeter_hints (seat, greeter_session_get_greeter (greeter_session));
1542         existing = TRUE;
1543     }
1544     else
1545     {
1546         l_debug (seat, "Starting greeter to authenticate session");
1547         greeter_session = create_greeter_session (seat);
1548     }
1549     greeter = greeter_session_get_greeter (greeter_session);
1550
1551     if (session_get_is_guest (session))
1552         greeter_set_hint (greeter, "select-guest", "true");
1553     else
1554         greeter_set_hint (greeter, "select-user", session_get_username (session));
1555
1556     if (existing)
1557     {
1558         greeter_reset (greeter);
1559         seat_set_active_session (seat, SESSION (greeter_session));
1560     }
1561     else
1562     {
1563         g_clear_object (&seat->priv->session_to_activate);
1564         seat->priv->session_to_activate = g_object_ref (greeter_session);
1565
1566         display_server = create_display_server (seat, SESSION (greeter_session));
1567         session_set_display_server (SESSION (greeter_session), display_server);
1568         start_display_server (seat, display_server);
1569     }
1570 }
1571
1572 gboolean
1573 seat_switch_to_user (Seat *seat, const gchar *username, const gchar *session_name)
1574 {
1575     Session *session;
1576
1577     g_return_val_if_fail (seat != NULL, FALSE);
1578     g_return_val_if_fail (username != NULL, FALSE);
1579
1580     if (!seat_get_can_switch (seat))
1581         return FALSE;
1582
1583     /* If we're already on this session, then ignore */
1584     session = find_user_session (seat, username, NULL);
1585     if (session && session == seat->priv->active_session)
1586         return TRUE;
1587
1588     l_debug (seat, "Switching to user %s", username);
1589
1590     /* Attempt to authenticate them */
1591     session = create_user_session (seat, username, FALSE);
1592     g_signal_connect (session, SESSION_SIGNAL_AUTHENTICATION_COMPLETE, G_CALLBACK (switch_authentication_complete_cb), seat);
1593     session_set_pam_service (session, seat_get_string_property (seat, "pam-service"));
1594
1595     return session_start (session);
1596 }
1597
1598 static Session *
1599 find_guest_session (Seat *seat)
1600 {
1601     GList *link;
1602
1603     for (link = seat->priv->sessions; link; link = link->next)
1604     {
1605         Session *session = link->data;
1606         if (!session_get_is_stopping (session) && session_get_is_guest (session))
1607             return session;
1608     }
1609
1610     return NULL;
1611 }
1612
1613 gboolean
1614 seat_switch_to_guest (Seat *seat, const gchar *session_name)
1615 {
1616     Session *session;
1617     DisplayServer *display_server;
1618
1619     g_return_val_if_fail (seat != NULL, FALSE);
1620
1621     if (!seat_get_can_switch (seat) || !seat_get_allow_guest (seat))
1622         return FALSE;
1623
1624     /* Switch to session if one open */
1625     session = find_guest_session (seat);
1626     if (session)
1627     {
1628         l_debug (seat, "Switching to existing guest account %s", session_get_username (session));
1629         seat_set_active_session (seat, session);
1630         return TRUE;
1631     }
1632
1633     session = create_guest_session (seat, session_name);
1634     if (!session)
1635         return FALSE;
1636
1637     display_server = create_display_server (seat, session);
1638
1639     g_clear_object (&seat->priv->session_to_activate);
1640     seat->priv->session_to_activate = g_object_ref (session);
1641     session_set_pam_service (session, seat_get_string_property (seat, "pam-autologin-service"));
1642     session_set_display_server (session, display_server);
1643
1644     return start_display_server (seat, display_server);
1645 }
1646
1647 gboolean
1648 seat_lock (Seat *seat, const gchar *username)
1649 {
1650     GreeterSession *greeter_session;
1651     Greeter *greeter;
1652     DisplayServer *display_server = NULL;
1653     gboolean reset_existing = FALSE;
1654     gboolean reuse_xserver = FALSE;
1655
1656     g_return_val_if_fail (seat != NULL, FALSE);
1657
1658     if (!seat_get_can_switch (seat))
1659         return FALSE;
1660
1661     // FIXME: If already locked then don't bother...
1662
1663     l_debug (seat, "Locking");
1664
1665     /* Switch to greeter we can reuse */
1666     greeter_session = find_resettable_greeter (seat);
1667     if (greeter_session)
1668     {
1669         l_debug (seat, "Switching to existing greeter");
1670         set_greeter_hints (seat, greeter_session_get_greeter (greeter_session));
1671         reset_existing = TRUE;
1672     }
1673     else
1674     {
1675         /* If the existing greeter can't be reused, stop it and reuse its display server */
1676         greeter_session = find_greeter_session (seat);
1677         if (greeter_session)
1678         {
1679             display_server = session_get_display_server (SESSION (greeter_session));
1680             if (!session_get_is_stopping (SESSION (greeter_session)))
1681             {
1682                 l_debug (seat, "Stopping session");
1683                 session_stop (SESSION (greeter_session));
1684             }
1685             reuse_xserver = TRUE;
1686         }
1687
1688         greeter_session = create_greeter_session (seat);
1689         if (!greeter_session)
1690             return FALSE;
1691     }
1692     greeter = greeter_session_get_greeter (greeter_session);
1693
1694     greeter_set_hint (greeter, "lock-screen", "true");
1695     if (username)
1696         greeter_set_hint (greeter, "select-user", username);
1697
1698     if (reset_existing)
1699     {
1700         greeter_reset (greeter);
1701         seat_set_active_session (seat, SESSION (greeter_session));
1702         return TRUE;
1703     }
1704     else
1705     {
1706         if (!reuse_xserver)
1707             display_server = create_display_server (seat, SESSION (greeter_session));
1708         session_set_display_server (SESSION (greeter_session), display_server);
1709
1710         g_clear_object (&seat->priv->session_to_activate);
1711         seat->priv->session_to_activate = g_object_ref (greeter_session);
1712
1713         if (reuse_xserver)
1714         {
1715             g_clear_object (&seat->priv->replacement_greeter);
1716             seat->priv->replacement_greeter = g_object_ref (greeter_session);
1717             return TRUE;
1718         }
1719         else
1720             return start_display_server (seat, display_server);
1721     }
1722 }
1723
1724 void
1725 seat_stop (Seat *seat)
1726 {
1727     g_return_if_fail (seat != NULL);
1728
1729     if (seat->priv->stopping)
1730         return;
1731
1732     l_debug (seat, "Stopping");
1733     seat->priv->stopping = TRUE;
1734     SEAT_GET_CLASS (seat)->stop (seat);
1735 }
1736
1737 gboolean
1738 seat_get_is_stopping (Seat *seat)
1739 {
1740     g_return_val_if_fail (seat != NULL, FALSE);
1741     return seat->priv->stopping;
1742 }
1743
1744 static void
1745 seat_real_setup (Seat *seat)
1746 {
1747 }
1748
1749 static gboolean
1750 seat_real_start (Seat *seat)
1751 {
1752     const gchar *autologin_username;
1753     int autologin_timeout;
1754     gboolean autologin_guest;
1755     gboolean autologin_in_background;
1756     Session *session = NULL, *background_session = NULL;
1757
1758     /* Get autologin settings */
1759     autologin_username = seat_get_string_property (seat, "autologin-user");
1760     if (g_strcmp0 (autologin_username, "") == 0)
1761         autologin_username = NULL;
1762     autologin_timeout = seat_get_integer_property (seat, "autologin-user-timeout");
1763     autologin_guest = seat_get_boolean_property (seat, "autologin-guest");
1764     autologin_in_background = seat_get_boolean_property (seat, "autologin-in-background");
1765
1766     /* Autologin if configured */
1767     if (autologin_timeout == 0 || autologin_in_background)
1768     {
1769         if (autologin_guest)
1770             session = create_guest_session (seat, NULL);
1771         else if (autologin_username != NULL)
1772             session = create_user_session (seat, autologin_username, TRUE);
1773
1774         if (session)
1775             session_set_pam_service (session, seat_get_string_property (seat, "pam-autologin-service"));
1776
1777         /* Load in background if required */
1778         if (autologin_in_background && session)
1779         {
1780             background_session = session;
1781             session = NULL;
1782         }
1783
1784         if (session)
1785         {
1786             DisplayServer *display_server;
1787
1788             g_clear_object (&seat->priv->session_to_activate);
1789             seat->priv->session_to_activate = g_object_ref (session);
1790
1791             display_server = create_display_server (seat, session);
1792             session_set_display_server (session, display_server);
1793             if (!display_server || !start_display_server (seat, display_server))
1794             {
1795                 l_debug (seat, "Can't create display server for automatic login");
1796                 session_stop (session);
1797                 if (display_server)
1798                     display_server_stop (display_server);
1799                 session = NULL;
1800             }
1801         }
1802     }
1803
1804     /* Fallback to a greeter */
1805     if (!session)
1806     {
1807         GreeterSession *greeter_session;
1808         DisplayServer *display_server;
1809
1810         greeter_session = create_greeter_session (seat);
1811         if (!greeter_session)
1812         {
1813             l_debug (seat, "Failed to create greeter session");
1814             return FALSE;
1815         }
1816
1817         g_clear_object (&seat->priv->session_to_activate);
1818         seat->priv->session_to_activate = g_object_ref (greeter_session);
1819         session = SESSION (greeter_session);
1820
1821         display_server = create_display_server (seat, session);
1822         session_set_display_server (session, display_server);
1823         if (!display_server || !start_display_server (seat, display_server))
1824         {
1825             l_debug (seat, "Can't create display server for greeter");
1826             session_stop (session);
1827             if (display_server)
1828                 display_server_stop (display_server);
1829             session = NULL;
1830         }
1831     }
1832
1833     /* Fail if can't start a session */
1834     if (!session)
1835     {
1836         seat_stop (seat);
1837         return FALSE;
1838     }
1839
1840     /* Start background session */
1841     if (background_session)
1842     {
1843         DisplayServer *background_display_server;
1844
1845         background_display_server = create_display_server (seat, background_session);
1846         session_set_display_server (background_session, background_display_server);
1847         if (!start_display_server (seat, background_display_server))
1848             l_warning (seat, "Failed to start display server for background session");
1849     }
1850
1851     return TRUE;
1852 }
1853
1854 static DisplayServer *
1855 seat_real_create_display_server (Seat *seat, Session *session)
1856 {
1857     return NULL;
1858 }
1859
1860 static gboolean
1861 seat_real_display_server_is_used (Seat *seat, DisplayServer *display_server)
1862 {
1863     GList *link;
1864
1865     for (link = seat->priv->sessions; link; link = link->next)
1866     {
1867         Session *session = link->data;
1868         DisplayServer *d;
1869
1870         d = session_get_display_server (session);
1871         if (!d)
1872             continue;
1873
1874         if (d == display_server || display_server_get_parent (d) == display_server)
1875             return TRUE;
1876     }
1877
1878     return FALSE;
1879 }
1880
1881 static GreeterSession *
1882 seat_real_create_greeter_session (Seat *seat)
1883 {
1884     return greeter_session_new ();
1885 }
1886
1887 static Session *
1888 create_session_cb (Greeter *greeter, Seat *seat)
1889 {
1890     return g_object_ref (create_session (seat, FALSE));
1891 }
1892
1893 static Greeter *
1894 create_greeter_cb (Session *session, Seat *seat)
1895 {
1896     Greeter *greeter;
1897
1898     greeter = greeter_new ();
1899     greeter_set_pam_services (greeter,
1900                               seat_get_string_property (seat, "pam-service"),
1901                               seat_get_string_property (seat, "pam-autologin-service"));
1902     g_signal_connect (greeter, GREETER_SIGNAL_CREATE_SESSION, G_CALLBACK (create_session_cb), seat);
1903     g_signal_connect (greeter, GREETER_SIGNAL_START_SESSION, G_CALLBACK (greeter_start_session_cb), seat);
1904
1905     return greeter;
1906 }
1907
1908 static Session *
1909 seat_real_create_session (Seat *seat)
1910 {
1911     Session *session;
1912
1913     session = session_new ();
1914     g_signal_connect (session, SESSION_SIGNAL_CREATE_GREETER, G_CALLBACK (create_greeter_cb), seat);
1915
1916     return session;
1917 }
1918
1919 static void
1920 seat_real_set_active_session (Seat *seat, Session *session)
1921 {
1922 }
1923
1924 static void
1925 seat_real_set_next_session (Seat *seat, Session *session)
1926 {
1927 }
1928
1929 static Session *
1930 seat_real_get_active_session (Seat *seat)
1931 {
1932     return NULL;
1933 }
1934
1935 static void
1936 seat_real_stop (Seat *seat)
1937 {
1938     GList *list, *link;
1939
1940     check_stopped (seat);
1941     if (seat->priv->stopped)
1942         return;
1943
1944     /* Stop all the display servers and sessions on the seat. Copy the list as
1945      * it might be modified if a display server / session stops during this loop */
1946     list = g_list_copy (seat->priv->display_servers);
1947     for (link = list; link; link = link->next)
1948         g_object_ref (link->data);
1949     for (link = list; link; link = link->next)
1950     {
1951         DisplayServer *display_server = link->data;
1952         if (!display_server_get_is_stopping (display_server))
1953         {
1954             l_debug (seat, "Stopping display server");
1955             display_server_stop (display_server);
1956         }
1957     }
1958     g_list_free_full (list, g_object_unref);
1959     list = g_list_copy (seat->priv->sessions);
1960     for (link = list; link; link = link->next)
1961         g_object_ref (link->data);
1962     for (link = list; link; link = link->next)
1963     {
1964         Session *session = link->data;
1965         if (!session_get_is_stopping (session))
1966         {
1967             l_debug (seat, "Stopping session");
1968             session_stop (session);
1969         }
1970     }
1971     g_list_free_full (list, g_object_unref);
1972 }
1973
1974 static void
1975 seat_init (Seat *seat)
1976 {
1977     seat->priv = G_TYPE_INSTANCE_GET_PRIVATE (seat, SEAT_TYPE, SeatPrivate);
1978     seat->priv->properties = g_hash_table_new_full (g_str_hash, g_str_equal, g_free, g_free);
1979     seat->priv->share_display_server = TRUE;
1980 }
1981
1982 static void
1983 seat_finalize (GObject *object)
1984 {
1985     Seat *self = SEAT (object);
1986     GList *link;
1987
1988     g_free (self->priv->name);
1989     g_hash_table_unref (self->priv->properties);
1990     for (link = self->priv->display_servers; link; link = link->next)
1991     {
1992         DisplayServer *display_server = link->data;
1993         g_signal_handlers_disconnect_matched (display_server, G_SIGNAL_MATCH_DATA, 0, 0, NULL, NULL, self);
1994     }
1995     g_list_free_full (self->priv->display_servers, g_object_unref);
1996     for (link = self->priv->sessions; link; link = link->next)
1997     {
1998         Session *session = link->data;
1999         g_signal_handlers_disconnect_matched (session, G_SIGNAL_MATCH_DATA, 0, 0, NULL, NULL, self);
2000     }
2001     g_list_free_full (self->priv->sessions, g_object_unref);
2002     g_clear_object (&self->priv->active_session);
2003     g_clear_object (&self->priv->next_session);
2004     g_clear_object (&self->priv->session_to_activate);
2005     g_clear_object (&self->priv->replacement_greeter);
2006
2007     G_OBJECT_CLASS (seat_parent_class)->finalize (object);
2008 }
2009
2010 static void
2011 seat_class_init (SeatClass *klass)
2012 {
2013     GObjectClass *object_class = G_OBJECT_CLASS (klass);
2014
2015     klass->setup = seat_real_setup;
2016     klass->start = seat_real_start;
2017     klass->create_display_server = seat_real_create_display_server;
2018     klass->display_server_is_used = seat_real_display_server_is_used;
2019     klass->create_greeter_session = seat_real_create_greeter_session;
2020     klass->create_session = seat_real_create_session;
2021     klass->set_active_session = seat_real_set_active_session;
2022     klass->get_active_session = seat_real_get_active_session;
2023     klass->set_next_session = seat_real_set_next_session;
2024     klass->run_script = seat_real_run_script;
2025     klass->stop = seat_real_stop;
2026
2027     object_class->finalize = seat_finalize;
2028
2029     g_type_class_add_private (klass, sizeof (SeatPrivate));
2030
2031     signals[SESSION_ADDED] =
2032         g_signal_new (SEAT_SIGNAL_SESSION_ADDED,
2033                       G_TYPE_FROM_CLASS (klass),
2034                       G_SIGNAL_RUN_LAST,
2035                       G_STRUCT_OFFSET (SeatClass, session_added),
2036                       NULL, NULL,
2037                       NULL,
2038                       G_TYPE_NONE, 1, SESSION_TYPE);
2039     signals[RUNNING_USER_SESSION] =
2040         g_signal_new (SEAT_SIGNAL_RUNNING_USER_SESSION,
2041                       G_TYPE_FROM_CLASS (klass),
2042                       G_SIGNAL_RUN_LAST,
2043                       G_STRUCT_OFFSET (SeatClass, running_user_session),
2044                       NULL, NULL,
2045                       NULL,
2046                       G_TYPE_NONE, 1, SESSION_TYPE);
2047     signals[SESSION_REMOVED] =
2048         g_signal_new (SEAT_SIGNAL_SESSION_REMOVED,
2049                       G_TYPE_FROM_CLASS (klass),
2050                       G_SIGNAL_RUN_LAST,
2051                       G_STRUCT_OFFSET (SeatClass, session_removed),
2052                       NULL, NULL,
2053                       NULL,
2054                       G_TYPE_NONE, 1, SESSION_TYPE);
2055     signals[STOPPED] =
2056         g_signal_new (SEAT_SIGNAL_STOPPED,
2057                       G_TYPE_FROM_CLASS (klass),
2058                       G_SIGNAL_RUN_LAST,
2059                       G_STRUCT_OFFSET (SeatClass, stopped),
2060                       NULL, NULL,
2061                       NULL,
2062                       G_TYPE_NONE, 0);
2063 }
2064
2065 static gint
2066 seat_real_logprefix (Logger *self, gchar *buf, gulong buflen)
2067 {
2068     return g_snprintf (buf, buflen, "Seat %s: ", SEAT (self)->priv->name);
2069 }
2070
2071 static void
2072 seat_logger_iface_init (LoggerInterface *iface)
2073 {
2074     iface->logprefix = &seat_real_logprefix;
2075 }