src/seat-unity.c

   1 /*
   2  * Copyright (C) 2012-2013 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 <string.h>
  13 #include <fcntl.h>
  14 #include <errno.h>
  15
  16 #include "seat-unity.h"
  17 #include "configuration.h"
  18 #include "xserver-local.h"
  19 #include "xgreeter.h"
  20 #include "xsession.h"
  21 #include "vt.h"
  22 #include "plymouth.h"
  23
  24 typedef enum
  25 {
  26    USC_MESSAGE_PING = 0,
  27    USC_MESSAGE_PONG = 1,
  28    USC_MESSAGE_READY = 2,
  29    USC_MESSAGE_SESSION_CONNECTED = 3,
  30    USC_MESSAGE_SET_ACTIVE_SESSION = 4
  31 } USCMessageID;
  32
  33 struct SeatUnityPrivate
  34 {
  35     /* VT we are running on */
  36     gint vt;
  37
  38     /* TRUE if waiting for X server to start before stopping Plymouth */
  39     gboolean stopping_plymouth;
  40
  41     /* File to log to */
  42     gchar *log_file;
  43
  44     /* Filename of Mir socket */
  45     gchar *mir_socket_filename;
  46
  47     /* Pipes to communicate with compositor */
  48     int to_compositor_pipe[2];
  49     int from_compositor_pipe[2];
  50
  51     /* IO channel listening on for messages from the compositor */
  52     GIOChannel *from_compositor_channel;
  53
  54     /* TRUE when the compositor indicates it is ready */
  55     gboolean compositor_ready;
  56
  57     /* Buffer reading from channel */
  58     guint8 *read_buffer;
  59     gsize read_buffer_length;
  60     gsize read_buffer_n_used;
  61
  62     /* Compositor process */
  63     Process *compositor_process;
  64
  65     /* Timeout when waiting for compositor to start */
  66     guint compositor_timeout;
  67
  68     /* Next Mir ID to use for a compositor client */
  69     gint next_id;
  70
  71     /* TRUE if using VT switching fallback */
  72     gboolean use_vt_switching;
  73
  74     /* The currently visible session */
  75     Session *active_session;
  76     DisplayServer *active_display_server;
  77 };
  78
  79 G_DEFINE_TYPE (SeatUnity, seat_unity, SEAT_TYPE);
  80
  81 static void
  82 seat_unity_setup (Seat *seat)
  83 {
  84     seat_set_can_switch (seat, TRUE);
  85     SEAT_CLASS (seat_unity_parent_class)->setup (seat);
  86 }
  87
  88 static void
  89 compositor_stopped_cb (Process *process, SeatUnity *seat)
  90 {
  91     if (seat->priv->compositor_timeout != 0)
  92         g_source_remove (seat->priv->compositor_timeout);
  93     seat->priv->compositor_timeout = 0;
  94
  95     /* Finished with the VT */
  96     vt_unref (seat->priv->vt);
  97     seat->priv->vt = -1;
  98
  99     if (seat_get_is_stopping (SEAT (seat)))
 100     {
 101         SEAT_CLASS (seat_unity_parent_class)->stop (SEAT (seat));
 102         return;
 103     }
 104
 105     /* If stopped before it was ready, then revert to VT mode */
 106     if (!seat->priv->compositor_ready)
 107     {
 108         g_debug ("Compositor failed to start, switching to VT mode");
 109         seat->priv->use_vt_switching = TRUE;
 110         SEAT_CLASS (seat_unity_parent_class)->start (SEAT (seat));
 111         return;
 112     }
 113
 114     g_debug ("Stopping Unity seat, compositor terminated");
 115
 116     if (seat->priv->stopping_plymouth)
 117     {
 118         g_debug ("Stopping Plymouth, compositor failed to start");
 119         plymouth_quit (FALSE);
 120         seat->priv->stopping_plymouth = FALSE;
 121     }
 122
 123     seat_stop (SEAT (seat));
 124 }
 125
 126 static void
 127 compositor_run_cb (Process *process, SeatUnity *seat)
 128 {
 129     int fd;
 130
 131     /* Make input non-blocking */
 132     fd = open ("/dev/null", O_RDONLY);
 133     dup2 (fd, STDIN_FILENO);
 134     close (fd);
 135
 136     /* Redirect output to logfile */
 137     if (seat->priv->log_file)
 138     {
 139          int fd;
 140
 141          fd = g_open (seat->priv->log_file, O_WRONLY | O_CREAT | O_TRUNC, 0600);
 142          if (fd < 0)
 143              g_warning ("Failed to open log file %s: %s", seat->priv->log_file, g_strerror (errno));
 144          else
 145          {
 146              dup2 (fd, STDOUT_FILENO);
 147              dup2 (fd, STDERR_FILENO);
 148              close (fd);
 149          }
 150     }
 151
 152     if (seat->priv->stopping_plymouth)
 153     {
 154         seat->priv->stopping_plymouth = FALSE;
 155         plymouth_quit (TRUE);
 156     }
 157 }
 158
 159 static void
 160 write_message (SeatUnity *seat, guint16 id, const guint8 *payload, guint16 payload_length)
 161 {
 162     guint8 *data;
 163     gsize data_length = 4 + payload_length;
 164
 165     data = g_malloc (data_length);
 166     data[0] = id >> 8;
 167     data[1] = id & 0xFF;
 168     data[2] = payload_length >> 8;
 169     data[3] = payload_length & 0xFF;
 170     memcpy (data + 4, payload, payload_length);
 171
 172     errno = 0;
 173     if (write (seat->priv->to_compositor_pipe[1], data, data_length) != data_length)
 174         g_warning ("Failed to write to compositor: %s", strerror (errno));
 175 }
 176
 177 static gboolean
 178 read_cb (GIOChannel *source, GIOCondition condition, gpointer data)
 179 {
 180     SeatUnity *seat = data;
 181     gsize n_to_read = 0;
 182     guint16 id, payload_length;
 183     guint8 *payload;
 184
 185     if (condition == G_IO_HUP)
 186     {
 187         g_debug ("Compositor closed communication channel");
 188         return FALSE;
 189     }
 190
 191     /* Work out how much required for a message */
 192     if (seat->priv->read_buffer_n_used < 4)
 193         n_to_read = 4 - seat->priv->read_buffer_n_used;
 194     else
 195     {
 196         payload_length = seat->priv->read_buffer[2] << 8 | seat->priv->read_buffer[3];
 197         n_to_read = 4 + payload_length - seat->priv->read_buffer_n_used;
 198     }
 199
 200     /* Read from compositor */
 201     if (n_to_read > 0)
 202     {
 203         gsize n_total, n_read = 0;
 204         GIOStatus status;
 205         GError *error = NULL;
 206
 207         n_total = seat->priv->read_buffer_n_used + n_to_read;
 208         if (seat->priv->read_buffer_length < n_total)
 209             seat->priv->read_buffer = g_realloc (seat->priv->read_buffer, n_total);
 210
 211         status = g_io_channel_read_chars (source,
 212                                           seat->priv->read_buffer + seat->priv->read_buffer_n_used,
 213                                           n_to_read,
 214                                           &n_read,
 215                                           &error);
 216         if (error)
 217             g_warning ("Failed to read from compositor: %s", error->message);
 218         if (status != G_IO_STATUS_NORMAL)
 219             return TRUE;
 220         g_clear_error (&error);
 221         seat->priv->read_buffer_n_used += n_read;
 222     }
 223
 224     /* Read header */
 225     if (seat->priv->read_buffer_n_used < 4)
 226          return TRUE;
 227     id = seat->priv->read_buffer[0] << 8 | seat->priv->read_buffer[1];
 228     payload_length = seat->priv->read_buffer[2] << 8 | seat->priv->read_buffer[3];
 229
 230     /* Read payload */
 231     if (seat->priv->read_buffer_n_used < 4 + payload_length)
 232         return TRUE;
 233     payload = seat->priv->read_buffer + 4;
 234
 235     switch (id)
 236     {
 237     case USC_MESSAGE_PING:
 238         g_debug ("PING!");
 239         write_message (seat, USC_MESSAGE_PONG, NULL, 0);
 240         break;
 241     case USC_MESSAGE_PONG:
 242         g_debug ("PONG!");
 243         break;
 244     case USC_MESSAGE_READY:
 245         g_debug ("READY");
 246         if (!seat->priv->compositor_ready)
 247         {
 248             seat->priv->compositor_ready = TRUE;
 249             g_debug ("Compositor ready");
 250             g_source_remove (seat->priv->compositor_timeout);
 251             seat->priv->compositor_timeout = 0;
 252             SEAT_CLASS (seat_unity_parent_class)->start (SEAT (seat));
 253         }
 254         break;
 255     case USC_MESSAGE_SESSION_CONNECTED:
 256         g_debug ("SESSION CONNECTED");
 257         break;
 258     default:
 259         g_warning ("Ingoring unknown message %d with %d octets from system compositor", id, payload_length);
 260         break;
 261     }
 262
 263     /* Clear buffer */
 264     seat->priv->read_buffer_n_used = 0;
 265
 266     return TRUE;
 267 }
 268
 269 static gchar *
 270 get_absolute_command (const gchar *command)
 271 {
 272     gchar **tokens;
 273     gchar *absolute_binary, *absolute_command = NULL;
 274
 275     tokens = g_strsplit (command, " ", 2);
 276
 277     absolute_binary = g_find_program_in_path (tokens[0]);
 278     if (absolute_binary)
 279     {
 280         if (tokens[1])
 281             absolute_command = g_strjoin (" ", absolute_binary, tokens[1], NULL);
 282         else
 283             absolute_command = g_strdup (absolute_binary);
 284         g_free (absolute_binary);
 285     }
 286     else
 287         absolute_command = g_strdup (command);
 288
 289     g_strfreev (tokens);
 290
 291     return absolute_command;
 292 }
 293
 294 static gboolean
 295 compositor_timeout_cb (gpointer data)
 296 {
 297     SeatUnity *seat = data;
 298
 299     /* Stop the compositor - it is not working */
 300     process_stop (seat->priv->compositor_process);
 301
 302     return TRUE;
 303 }
 304
 305 static gboolean
 306 seat_unity_start (Seat *seat)
 307 {
 308     const gchar *compositor_command;
 309     gchar *command, *absolute_command, *dir;
 310     gboolean result;
 311     int timeout;
 312
 313     /* Replace Plymouth if it is running */
 314     if (plymouth_get_is_active () && plymouth_has_active_vt ())
 315     {
 316         gint active_vt = vt_get_active ();
 317         if (active_vt >= vt_get_min ())
 318         {
 319             g_debug ("Compositor will replace Plymouth");
 320             SEAT_UNITY (seat)->priv->stopping_plymouth = TRUE;
 321             SEAT_UNITY (seat)->priv->vt = active_vt;
 322             plymouth_deactivate ();
 323         }
 324         else
 325             g_debug ("Plymouth is running on VT %d, but this is less than the configured minimum of %d so not replacing it", active_vt, vt_get_min ());
 326     }
 327     if (SEAT_UNITY (seat)->priv->vt < 0)
 328         SEAT_UNITY (seat)->priv->vt = vt_get_unused ();
 329     if (SEAT_UNITY (seat)->priv->vt < 0)
 330     {
 331         g_debug ("Failed to get a VT to run on");
 332         return FALSE;
 333     }
 334     vt_ref (SEAT_UNITY (seat)->priv->vt);
 335
 336     /* Create pipes to talk to compositor */
 337     if (pipe (SEAT_UNITY (seat)->priv->to_compositor_pipe) < 0 || pipe (SEAT_UNITY (seat)->priv->from_compositor_pipe) < 0)
 338     {
 339         g_debug ("Failed to create compositor pipes: %s", g_strerror (errno));
 340         return FALSE;
 341     }
 342
 343     /* Don't allow the daemon end of the pipes to be accessed in the compositor */
 344     fcntl (SEAT_UNITY (seat)->priv->to_compositor_pipe[1], F_SETFD, FD_CLOEXEC);
 345     fcntl (SEAT_UNITY (seat)->priv->from_compositor_pipe[0], F_SETFD, FD_CLOEXEC);
 346
 347     /* Listen for messages from the compositor */
 348     SEAT_UNITY (seat)->priv->from_compositor_channel = g_io_channel_unix_new (SEAT_UNITY (seat)->priv->from_compositor_pipe[0]);
 349     g_io_add_watch (SEAT_UNITY (seat)->priv->from_compositor_channel, G_IO_IN | G_IO_HUP, read_cb, seat);
 350
 351     /* Setup logging */
 352     dir = config_get_string (config_get_instance (), "LightDM", "log-directory");
 353     SEAT_UNITY (seat)->priv->log_file = g_build_filename (dir, "unity-system-compositor.log", NULL);
 354     g_debug ("Logging to %s", SEAT_UNITY (seat)->priv->log_file);
 355     g_free (dir);
 356
 357     SEAT_UNITY (seat)->priv->mir_socket_filename = g_strdup ("/tmp/mir_socket"); // FIXME: Use this socket by default as XMir is hardcoded to this
 358     timeout = seat_get_integer_property (seat, "unity-compositor-timeout");
 359     compositor_command = seat_get_string_property (seat, "unity-compositor-command");
 360     command = g_strdup_printf ("%s --from-dm-fd %d --to-dm-fd %d --vt %d", compositor_command, SEAT_UNITY (seat)->priv->to_compositor_pipe[0], SEAT_UNITY (seat)->priv->from_compositor_pipe[1], SEAT_UNITY (seat)->priv->vt);
 361
 362     absolute_command = get_absolute_command (command);
 363     g_free (command);
 364
 365     /* Start the compositor */
 366     process_set_command (SEAT_UNITY (seat)->priv->compositor_process, absolute_command);
 367     g_free (absolute_command);
 368     g_signal_connect (SEAT_UNITY (seat)->priv->compositor_process, "stopped", G_CALLBACK (compositor_stopped_cb), seat);
 369     g_signal_connect (SEAT_UNITY (seat)->priv->compositor_process, "run", G_CALLBACK (compositor_run_cb), seat);
 370     result = process_start (SEAT_UNITY (seat)->priv->compositor_process, FALSE);
 371
 372     /* Close compostor ends of the pipes */
 373     close (SEAT_UNITY (seat)->priv->to_compositor_pipe[0]);
 374     SEAT_UNITY (seat)->priv->to_compositor_pipe[0] = 0;
 375     close (SEAT_UNITY (seat)->priv->from_compositor_pipe[1]);
 376     SEAT_UNITY (seat)->priv->from_compositor_pipe[1] = 0;
 377
 378     if (!result)
 379         return FALSE;
 380
 381     /* Connect to the compositor */
 382     timeout = seat_get_integer_property (seat, "unity-compositor-timeout");
 383     if (timeout <= 0)
 384         timeout = 60;
 385     g_debug ("Waiting for system compositor for %ds", timeout);
 386     SEAT_UNITY (seat)->priv->compositor_timeout = g_timeout_add (timeout * 1000, compositor_timeout_cb, seat);
 387
 388     return TRUE;
 389 }
 390
 391 static DisplayServer *
 392 seat_unity_create_display_server (Seat *seat)
 393 {
 394     XServerLocal *xserver;
 395     const gchar *command = NULL, *layout = NULL, *config_file = NULL, *xdmcp_manager = NULL, *key_name = NULL;
 396     gboolean allow_tcp;
 397     gint port = 0;
 398     gchar *id;
 399
 400     g_debug ("Starting X server on Unity compositor");
 401
 402     xserver = xserver_local_new ();
 403
 404     if (!SEAT_UNITY (seat)->priv->use_vt_switching)
 405     {
 406         id = g_strdup_printf ("%d", SEAT_UNITY (seat)->priv->next_id);
 407         SEAT_UNITY (seat)->priv->next_id++;
 408         xserver_local_set_mir_id (xserver, id);
 409         xserver_local_set_mir_socket (xserver, SEAT_UNITY (seat)->priv->mir_socket_filename);
 410         g_free (id);
 411     }
 412
 413     command = seat_get_string_property (seat, "xserver-command");
 414     if (command)
 415         xserver_local_set_command (xserver, command);
 416
 417     layout = seat_get_string_property (seat, "xserver-layout");
 418     if (layout)
 419         xserver_local_set_layout (xserver, layout);
 420
 421     config_file = seat_get_string_property (seat, "xserver-config");
 422     if (config_file)
 423         xserver_local_set_config (xserver, config_file);
 424
 425     allow_tcp = seat_get_boolean_property (seat, "xserver-allow-tcp");
 426     xserver_local_set_allow_tcp (xserver, allow_tcp);
 427
 428     xdmcp_manager = seat_get_string_property (seat, "xdmcp-manager");
 429     if (xdmcp_manager)
 430         xserver_local_set_xdmcp_server (xserver, xdmcp_manager);
 431
 432     port = seat_get_integer_property (seat, "xdmcp-port");
 433     if (port > 0)
 434         xserver_local_set_xdmcp_port (xserver, port);
 435
 436     key_name = seat_get_string_property (seat, "xdmcp-key");
 437     if (key_name)
 438     {
 439         gchar *dir, *path;
 440         GKeyFile *keys;
 441         gboolean result;
 442         GError *error = NULL;
 443
 444         dir = config_get_string (config_get_instance (), "LightDM", "config-directory");
 445         path = g_build_filename (dir, "keys.conf", NULL);
 446         g_free (dir);
 447
 448         keys = g_key_file_new ();
 449         result = g_key_file_load_from_file (keys, path, G_KEY_FILE_NONE, &error);
 450         if (error)
 451             g_debug ("Error getting key %s", error->message);
 452         g_clear_error (&error);
 453
 454         if (result)
 455         {
 456             gchar *key = NULL;
 457
 458             if (g_key_file_has_key (keys, "keyring", key_name, NULL))
 459                 key = g_key_file_get_string (keys, "keyring", key_name, NULL);
 460             else
 461                 g_debug ("Key %s not defined", key_name);
 462
 463             if (key)
 464                 xserver_local_set_xdmcp_key (xserver, key);
 465             g_free (key);
 466         }
 467
 468         g_free (path);
 469         g_key_file_free (keys);
 470     }
 471
 472     return DISPLAY_SERVER (xserver);
 473 }
 474
 475 static Greeter *
 476 seat_unity_create_greeter_session (Seat *seat)
 477 {
 478     XGreeter *greeter_session;
 479
 480     greeter_session = xgreeter_new ();
 481     session_set_env (SESSION (greeter_session), "XDG_SEAT", "seat0");
 482
 483     return GREETER (greeter_session);
 484 }
 485
 486 static Session *
 487 seat_unity_create_session (Seat *seat)
 488 {
 489     XSession *session;
 490
 491     session = xsession_new ();
 492     session_set_env (SESSION (session), "XDG_SEAT", "seat0");
 493
 494     return SESSION (session);
 495 }
 496
 497 static void
 498 seat_unity_set_active_session (Seat *seat, Session *session)
 499 {
 500     DisplayServer *display_server;
 501
 502     /* If no compositor, have to use VT switching */
 503     if (SEAT_UNITY (seat)->priv->use_vt_switching)
 504     {
 505         gint vt = display_server_get_vt (session_get_display_server (session));
 506         if (vt >= 0)
 507             vt_set_active (vt);
 508
 509         SEAT_CLASS (seat_unity_parent_class)->set_active_session (seat, session);
 510         return;
 511     }
 512
 513     if (session == SEAT_UNITY (seat)->priv->active_session)
 514         return;
 515     SEAT_UNITY (seat)->priv->active_session = g_object_ref (session);
 516
 517     display_server = session_get_display_server (session);
 518     if (SEAT_UNITY (seat)->priv->active_display_server != display_server)
 519     {
 520         const gchar *id;
 521
 522         SEAT_UNITY (seat)->priv->active_display_server = g_object_ref (display_server);
 523         id = xserver_local_get_mir_id (XSERVER_LOCAL (display_server));
 524
 525         g_debug ("Switching to Mir session %s", id);
 526         write_message (SEAT_UNITY (seat), USC_MESSAGE_SET_ACTIVE_SESSION, id, strlen (id));
 527     }
 528
 529     SEAT_CLASS (seat_unity_parent_class)->set_active_session (seat, session);
 530 }
 531
 532 static Session *
 533 seat_unity_get_active_session (Seat *seat)
 534 {
 535     if (SEAT_UNITY (seat)->priv->use_vt_switching)
 536     {
 537         gint vt;
 538         GList *link;
 539         vt = vt_get_active ();
 540         if (vt < 0)
 541             return NULL;
 542
 543         for (link = seat_get_sessions (seat); link; link = link->next)
 544         {
 545             Session *session = link->data;
 546             if (display_server_get_vt (session_get_display_server (session)) == vt)
 547                 return session;
 548         }
 549
 550         return NULL;
 551     }
 552
 553     return SEAT_UNITY (seat)->priv->active_session;
 554 }
 555
 556 static void
 557 seat_unity_run_script (Seat *seat, DisplayServer *display_server, Process *script)
 558 {
 559     const gchar *path;
 560     XServerLocal *xserver;
 561
 562     xserver = XSERVER_LOCAL (display_server);
 563     path = xserver_local_get_authority_file_path (xserver);
 564     process_set_env (script, "DISPLAY", xserver_get_address (XSERVER (xserver)));
 565     process_set_env (script, "XAUTHORITY", path);
 566
 567     SEAT_CLASS (seat_unity_parent_class)->run_script (seat, display_server, script);
 568 }
 569
 570 static void
 571 seat_unity_stop (Seat *seat)
 572 {
 573     /* Stop the compositor first */
 574     if (process_get_is_running (SEAT_UNITY (seat)->priv->compositor_process))
 575     {
 576         process_stop (SEAT_UNITY (seat)->priv->compositor_process);
 577         return;
 578     }
 579
 580     SEAT_CLASS (seat_unity_parent_class)->stop (seat);
 581 }
 582
 583 static void
 584 seat_unity_init (SeatUnity *seat)
 585 {
 586     seat->priv = G_TYPE_INSTANCE_GET_PRIVATE (seat, SEAT_UNITY_TYPE, SeatUnityPrivate);
 587     seat->priv->vt = -1;
 588     seat->priv->compositor_process = process_new ();
 589 }
 590
 591 static void
 592 seat_unity_finalize (GObject *object)
 593 {
 594     SeatUnity *seat = SEAT_UNITY (object);
 595
 596     if (seat->priv->vt >= 0)
 597         vt_unref (seat->priv->vt);
 598     g_free (seat->priv->log_file);
 599     g_free (seat->priv->mir_socket_filename);
 600     close (seat->priv->to_compositor_pipe[0]);
 601     close (seat->priv->to_compositor_pipe[1]);
 602     close (seat->priv->from_compositor_pipe[0]);
 603     close (seat->priv->from_compositor_pipe[1]);
 604     g_io_channel_unref (seat->priv->from_compositor_channel);
 605     g_free (seat->priv->read_buffer);
 606     g_object_unref (seat->priv->compositor_process);
 607     if (seat->priv->active_session)
 608         g_object_unref (seat->priv->active_session);
 609     if (seat->priv->active_display_server)
 610         g_object_unref (seat->priv->active_display_server);
 611
 612     G_OBJECT_CLASS (seat_unity_parent_class)->finalize (object);
 613 }
 614
 615 static void
 616 seat_unity_class_init (SeatUnityClass *klass)
 617 {
 618     GObjectClass *object_class = G_OBJECT_CLASS (klass);
 619     SeatClass *seat_class = SEAT_CLASS (klass);
 620
 621     object_class->finalize = seat_unity_finalize;
 622     seat_class->setup = seat_unity_setup;
 623     seat_class->start = seat_unity_start;
 624     seat_class->create_display_server = seat_unity_create_display_server;
 625     seat_class->create_greeter_session = seat_unity_create_greeter_session;
 626     seat_class->create_session = seat_unity_create_session;
 627     seat_class->set_active_session = seat_unity_set_active_session;
 628     seat_class->get_active_session = seat_unity_get_active_session;
 629     seat_class->run_script = seat_unity_run_script;
 630     seat_class->stop = seat_unity_stop;
 631
 632     g_type_class_add_private (klass, sizeof (SeatUnityPrivate));
 633 }