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 #include <glib/gstdio.h>
  16
  17 #include "seat-unity.h"
  18 #include "configuration.h"
  19 #include "x-server-local.h"
  20 #include "x-greeter.h"
  21 #include "x-session.h"
  22 #include "vt.h"
  23 #include "plymouth.h"
  24
  25 typedef enum
  26 {
  27    USC_MESSAGE_PING = 0,
  28    USC_MESSAGE_PONG = 1,
  29    USC_MESSAGE_READY = 2,
  30    USC_MESSAGE_SESSION_CONNECTED = 3,
  31    USC_MESSAGE_SET_ACTIVE_SESSION = 4
  32 } USCMessageID;
  33
  34 struct SeatUnityPrivate
  35 {
  36     /* VT we are running on */
  37     gint vt;
  38
  39     /* TRUE if waiting for X server to start before stopping Plymouth */
  40     gboolean stopping_plymouth;
  41
  42     /* File to log to */
  43     gchar *log_file;
  44
  45     /* Filename of Mir socket */
  46     gchar *mir_socket_filename;
  47
  48     /* Pipes to communicate with compositor */
  49     int to_compositor_pipe[2];
  50     int from_compositor_pipe[2];
  51
  52     /* IO channel listening on for messages from the compositor */
  53     GIOChannel *from_compositor_channel;
  54
  55     /* TRUE when the compositor indicates it is ready */
  56     gboolean compositor_ready;
  57
  58     /* Buffer reading from channel */
  59     guint8 *read_buffer;
  60     gsize read_buffer_length;
  61     gsize read_buffer_n_used;
  62
  63     /* Compositor process */
  64     Process *compositor_process;
  65
  66     /* Timeout when waiting for compositor to start */
  67     guint compositor_timeout;
  68
  69     /* Next Mir ID to use for a compositor client */
  70     gint next_id;
  71
  72     /* TRUE if using VT switching fallback */
  73     gboolean use_vt_switching;
  74
  75     /* The currently visible session */
  76     Session *active_session;
  77     DisplayServer *active_display_server;
  78 };
  79
  80 G_DEFINE_TYPE (SeatUnity, seat_unity, SEAT_TYPE);
  81
  82 static void
  83 seat_unity_setup (Seat *seat)
  84 {
  85     seat_set_can_switch (seat, TRUE);
  86     SEAT_CLASS (seat_unity_parent_class)->setup (seat);
  87 }
  88
  89 static void
  90 compositor_stopped_cb (Process *process, SeatUnity *seat)
  91 {
  92     if (seat->priv->compositor_timeout != 0)
  93         g_source_remove (seat->priv->compositor_timeout);
  94     seat->priv->compositor_timeout = 0;
  95
  96     /* Finished with the VT */
  97     vt_unref (seat->priv->vt);
  98     seat->priv->vt = -1;
  99
 100     if (seat_get_is_stopping (SEAT (seat)))
 101     {
 102         SEAT_CLASS (seat_unity_parent_class)->stop (SEAT (seat));
 103         return;
 104     }
 105
 106     /* If stopped before it was ready, then revert to VT mode */
 107     if (!seat->priv->compositor_ready)
 108     {
 109         g_debug ("Compositor failed to start, switching to VT mode");
 110         seat->priv->use_vt_switching = TRUE;
 111         SEAT_CLASS (seat_unity_parent_class)->start (SEAT (seat));
 112         return;
 113     }
 114
 115     g_debug ("Stopping Unity seat, compositor terminated");
 116
 117     if (seat->priv->stopping_plymouth)
 118     {
 119         g_debug ("Stopping Plymouth, compositor failed to start");
 120         plymouth_quit (FALSE);
 121         seat->priv->stopping_plymouth = FALSE;
 122     }
 123
 124     seat_stop (SEAT (seat));
 125 }
 126
 127 static void
 128 compositor_run_cb (Process *process, SeatUnity *seat)
 129 {
 130     int fd;
 131
 132     /* Make input non-blocking */
 133     fd = open ("/dev/null", O_RDONLY);
 134     dup2 (fd, STDIN_FILENO);
 135     close (fd);
 136
 137     /* Redirect output to logfile */
 138     if (seat->priv->log_file)
 139     {
 140          int fd;
 141
 142          fd = g_open (seat->priv->log_file, O_WRONLY | O_CREAT | O_TRUNC, 0600);
 143          if (fd < 0)
 144              g_warning ("Failed to open log file %s: %s", seat->priv->log_file, g_strerror (errno));
 145          else
 146          {
 147              dup2 (fd, STDOUT_FILENO);
 148              dup2 (fd, STDERR_FILENO);
 149              close (fd);
 150          }
 151     }
 152
 153     if (seat->priv->stopping_plymouth)
 154     {
 155         seat->priv->stopping_plymouth = FALSE;
 156         plymouth_quit (TRUE);
 157     }
 158 }
 159
 160 static void
 161 write_message (SeatUnity *seat, guint16 id, const guint8 *payload, guint16 payload_length)
 162 {
 163     guint8 *data;
 164     gsize data_length = 4 + payload_length;
 165
 166     data = g_malloc (data_length);
 167     data[0] = id >> 8;
 168     data[1] = id & 0xFF;
 169     data[2] = payload_length >> 8;
 170     data[3] = payload_length & 0xFF;
 171     memcpy (data + 4, payload, payload_length);
 172
 173     errno = 0;
 174     if (write (seat->priv->to_compositor_pipe[1], data, data_length) != data_length)
 175         g_warning ("Failed to write to compositor: %s", strerror (errno));
 176 }
 177
 178 static gboolean
 179 read_cb (GIOChannel *source, GIOCondition condition, gpointer data)
 180 {
 181     SeatUnity *seat = data;
 182     gsize n_to_read = 0;
 183     guint16 id, payload_length;
 184     /*guint8 *payload;*/
 185
 186     if (condition == G_IO_HUP)
 187     {
 188         g_debug ("Compositor closed communication channel");
 189         return FALSE;
 190     }
 191
 192     /* Work out how much required for a message */
 193     if (seat->priv->read_buffer_n_used < 4)
 194         n_to_read = 4 - seat->priv->read_buffer_n_used;
 195     else
 196     {
 197         payload_length = seat->priv->read_buffer[2] << 8 | seat->priv->read_buffer[3];
 198         n_to_read = 4 + payload_length - seat->priv->read_buffer_n_used;
 199     }
 200
 201     /* Read from compositor */
 202     if (n_to_read > 0)
 203     {
 204         gsize n_total, n_read = 0;
 205         GIOStatus status;
 206         GError *error = NULL;
 207
 208         n_total = seat->priv->read_buffer_n_used + n_to_read;
 209         if (seat->priv->read_buffer_length < n_total)
 210             seat->priv->read_buffer = g_realloc (seat->priv->read_buffer, n_total);
 211
 212         status = g_io_channel_read_chars (source,
 213                                           (gchar *)seat->priv->read_buffer + seat->priv->read_buffer_n_used,
 214                                           n_to_read,
 215                                           &n_read,
 216                                           &error);
 217         if (error)
 218             g_warning ("Failed to read from compositor: %s", error->message);
 219         if (status != G_IO_STATUS_NORMAL)
 220             return TRUE;
 221         g_clear_error (&error);
 222         seat->priv->read_buffer_n_used += n_read;
 223     }
 224
 225     /* Read header */
 226     if (seat->priv->read_buffer_n_used < 4)
 227          return TRUE;
 228     id = seat->priv->read_buffer[0] << 8 | seat->priv->read_buffer[1];
 229     payload_length = seat->priv->read_buffer[2] << 8 | seat->priv->read_buffer[3];
 230
 231     /* Read payload */
 232     if (seat->priv->read_buffer_n_used < 4 + payload_length)
 233         return TRUE;
 234     /*payload = seat->priv->read_buffer + 4;*/
 235
 236     switch (id)
 237     {
 238     case USC_MESSAGE_PING:
 239         g_debug ("PING!");
 240         write_message (seat, USC_MESSAGE_PONG, NULL, 0);
 241         break;
 242     case USC_MESSAGE_PONG:
 243         g_debug ("PONG!");
 244         break;
 245     case USC_MESSAGE_READY:
 246         g_debug ("READY");
 247         if (!seat->priv->compositor_ready)
 248         {
 249             seat->priv->compositor_ready = TRUE;
 250             g_debug ("Compositor ready");
 251             g_source_remove (seat->priv->compositor_timeout);
 252             seat->priv->compositor_timeout = 0;
 253             SEAT_CLASS (seat_unity_parent_class)->start (SEAT (seat));
 254         }
 255         break;
 256     case USC_MESSAGE_SESSION_CONNECTED:
 257         g_debug ("SESSION CONNECTED");
 258         break;
 259     default:
 260         g_warning ("Ingoring unknown message %d with %d octets from system compositor", id, payload_length);
 261         break;
 262     }
 263
 264     /* Clear buffer */
 265     seat->priv->read_buffer_n_used = 0;
 266
 267     return TRUE;
 268 }
 269
 270 static gchar *
 271 get_absolute_command (const gchar *command)
 272 {
 273     gchar **tokens;
 274     gchar *absolute_binary, *absolute_command = NULL;
 275
 276     tokens = g_strsplit (command, " ", 2);
 277
 278     absolute_binary = g_find_program_in_path (tokens[0]);
 279     if (absolute_binary)
 280     {
 281         if (tokens[1])
 282             absolute_command = g_strjoin (" ", absolute_binary, tokens[1], NULL);
 283         else
 284             absolute_command = g_strdup (absolute_binary);
 285         g_free (absolute_binary);
 286     }
 287     else
 288         absolute_command = g_strdup (command);
 289
 290     g_strfreev (tokens);
 291
 292     return absolute_command;
 293 }
 294
 295 static gboolean
 296 compositor_timeout_cb (gpointer data)
 297 {
 298     SeatUnity *seat = data;
 299
 300     /* Stop the compositor - it is not working */
 301     process_stop (seat->priv->compositor_process);
 302
 303     return TRUE;
 304 }
 305
 306 static gboolean
 307 seat_unity_start (Seat *seat)
 308 {
 309     const gchar *compositor_command;
 310     gchar *command, *absolute_command, *dir;
 311     gboolean result;
 312     int timeout;
 313
 314     /* Replace Plymouth if it is running */
 315     if (plymouth_get_is_active () && plymouth_has_active_vt ())
 316     {
 317         gint active_vt = vt_get_active ();
 318         if (active_vt >= vt_get_min ())
 319         {
 320             g_debug ("Compositor will replace Plymouth");
 321             SEAT_UNITY (seat)->priv->stopping_plymouth = TRUE;
 322             SEAT_UNITY (seat)->priv->vt = active_vt;
 323             plymouth_deactivate ();
 324         }
 325         else
 326             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 ());
 327     }
 328     if (SEAT_UNITY (seat)->priv->vt < 0)
 329         SEAT_UNITY (seat)->priv->vt = vt_get_unused ();
 330     if (SEAT_UNITY (seat)->priv->vt < 0)
 331     {
 332         g_debug ("Failed to get a VT to run on");
 333         return FALSE;
 334     }
 335     vt_ref (SEAT_UNITY (seat)->priv->vt);
 336
 337     /* Create pipes to talk to compositor */
 338     if (pipe (SEAT_UNITY (seat)->priv->to_compositor_pipe) < 0 || pipe (SEAT_UNITY (seat)->priv->from_compositor_pipe) < 0)
 339     {
 340         g_debug ("Failed to create compositor pipes: %s", g_strerror (errno));
 341         return FALSE;
 342     }
 343
 344     /* Don't allow the daemon end of the pipes to be accessed in the compositor */
 345     fcntl (SEAT_UNITY (seat)->priv->to_compositor_pipe[1], F_SETFD, FD_CLOEXEC);
 346     fcntl (SEAT_UNITY (seat)->priv->from_compositor_pipe[0], F_SETFD, FD_CLOEXEC);
 347
 348     /* Listen for messages from the compositor */
 349     SEAT_UNITY (seat)->priv->from_compositor_channel = g_io_channel_unix_new (SEAT_UNITY (seat)->priv->from_compositor_pipe[0]);
 350     g_io_add_watch (SEAT_UNITY (seat)->priv->from_compositor_channel, G_IO_IN | G_IO_HUP, read_cb, seat);
 351
 352     /* Setup logging */
 353     dir = config_get_string (config_get_instance (), "LightDM", "log-directory");
 354     SEAT_UNITY (seat)->priv->log_file = g_build_filename (dir, "unity-system-compositor.log", NULL);
 355     g_debug ("Logging to %s", SEAT_UNITY (seat)->priv->log_file);
 356     g_free (dir);
 357
 358     SEAT_UNITY (seat)->priv->mir_socket_filename = g_strdup ("/tmp/mir_socket"); // FIXME: Use this socket by default as XMir is hardcoded to this
 359     timeout = seat_get_integer_property (seat, "unity-compositor-timeout");
 360     compositor_command = seat_get_string_property (seat, "unity-compositor-command");
 361     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);
 362
 363     absolute_command = get_absolute_command (command);
 364     g_free (command);
 365
 366     /* Start the compositor */
 367     process_set_command (SEAT_UNITY (seat)->priv->compositor_process, absolute_command);
 368     g_free (absolute_command);
 369     g_signal_connect (SEAT_UNITY (seat)->priv->compositor_process, "stopped", G_CALLBACK (compositor_stopped_cb), seat);
 370     g_signal_connect (SEAT_UNITY (seat)->priv->compositor_process, "run", G_CALLBACK (compositor_run_cb), seat);
 371     result = process_start (SEAT_UNITY (seat)->priv->compositor_process, FALSE);
 372
 373     /* Close compostor ends of the pipes */
 374     close (SEAT_UNITY (seat)->priv->to_compositor_pipe[0]);
 375     SEAT_UNITY (seat)->priv->to_compositor_pipe[0] = 0;
 376     close (SEAT_UNITY (seat)->priv->from_compositor_pipe[1]);
 377     SEAT_UNITY (seat)->priv->from_compositor_pipe[1] = 0;
 378
 379     if (!result)
 380         return FALSE;
 381
 382     /* Connect to the compositor */
 383     timeout = seat_get_integer_property (seat, "unity-compositor-timeout");
 384     if (timeout <= 0)
 385         timeout = 60;
 386     g_debug ("Waiting for system compositor for %ds", timeout);
 387     SEAT_UNITY (seat)->priv->compositor_timeout = g_timeout_add (timeout * 1000, compositor_timeout_cb, seat);
 388
 389     return TRUE;
 390 }
 391
 392 static DisplayServer *
 393 seat_unity_create_display_server (Seat *seat)
 394 {
 395     XServerLocal *x_server;
 396     const gchar *command = NULL, *layout = NULL, *config_file = NULL, *xdmcp_manager = NULL, *key_name = NULL;
 397     gboolean allow_tcp;
 398     gint port = 0;
 399     gchar *id;
 400
 401     g_debug ("Starting X server on Unity compositor");
 402
 403     x_server = x_server_local_new ();
 404
 405     if (!SEAT_UNITY (seat)->priv->use_vt_switching)
 406     {
 407         id = g_strdup_printf ("%d", SEAT_UNITY (seat)->priv->next_id);
 408         SEAT_UNITY (seat)->priv->next_id++;
 409         x_server_local_set_mir_id (x_server, id);
 410         x_server_local_set_mir_socket (x_server, SEAT_UNITY (seat)->priv->mir_socket_filename);
 411         g_free (id);
 412     }
 413
 414     command = seat_get_string_property (seat, "xserver-command");
 415     if (command)
 416         x_server_local_set_command (x_server, command);
 417
 418     layout = seat_get_string_property (seat, "xserver-layout");
 419     if (layout)
 420         x_server_local_set_layout (x_server, layout);
 421
 422     config_file = seat_get_string_property (seat, "xserver-config");
 423     if (config_file)
 424         x_server_local_set_config (x_server, config_file);
 425
 426     allow_tcp = seat_get_boolean_property (seat, "xserver-allow-tcp");
 427     x_server_local_set_allow_tcp (x_server, allow_tcp);
 428
 429     xdmcp_manager = seat_get_string_property (seat, "xdmcp-manager");
 430     if (xdmcp_manager)
 431         x_server_local_set_xdmcp_server (x_server, xdmcp_manager);
 432
 433     port = seat_get_integer_property (seat, "xdmcp-port");
 434     if (port > 0)
 435         x_server_local_set_xdmcp_port (x_server, port);
 436
 437     key_name = seat_get_string_property (seat, "xdmcp-key");
 438     if (key_name)
 439     {
 440         gchar *dir, *path;
 441         GKeyFile *keys;
 442         gboolean result;
 443         GError *error = NULL;
 444
 445         dir = config_get_string (config_get_instance (), "LightDM", "config-directory");
 446         path = g_build_filename (dir, "keys.conf", NULL);
 447         g_free (dir);
 448
 449         keys = g_key_file_new ();
 450         result = g_key_file_load_from_file (keys, path, G_KEY_FILE_NONE, &error);
 451         if (error)
 452             g_debug ("Error getting key %s", error->message);
 453         g_clear_error (&error);
 454
 455         if (result)
 456         {
 457             gchar *key = NULL;
 458
 459             if (g_key_file_has_key (keys, "keyring", key_name, NULL))
 460                 key = g_key_file_get_string (keys, "keyring", key_name, NULL);
 461             else
 462                 g_debug ("Key %s not defined", key_name);
 463
 464             if (key)
 465                 x_server_local_set_xdmcp_key (x_server, key);
 466             g_free (key);
 467         }
 468
 469         g_free (path);
 470         g_key_file_free (keys);
 471     }
 472
 473     return DISPLAY_SERVER (x_server);
 474 }
 475
 476 static Greeter *
 477 seat_unity_create_greeter_session (Seat *seat)
 478 {
 479     XGreeter *greeter_session;
 480
 481     greeter_session = x_greeter_new ();
 482     session_set_env (SESSION (greeter_session), "XDG_SEAT", "seat0");
 483
 484     return GREETER (greeter_session);
 485 }
 486
 487 static Session *
 488 seat_unity_create_session (Seat *seat)
 489 {
 490     XSession *session;
 491
 492     session = x_session_new ();
 493     session_set_env (SESSION (session), "XDG_SEAT", "seat0");
 494
 495     return SESSION (session);
 496 }
 497
 498 static void
 499 seat_unity_set_active_session (Seat *seat, Session *session)
 500 {
 501     DisplayServer *display_server;
 502
 503     /* If no compositor, have to use VT switching */
 504     if (SEAT_UNITY (seat)->priv->use_vt_switching)
 505     {
 506         gint vt = display_server_get_vt (session_get_display_server (session));
 507         if (vt >= 0)
 508             vt_set_active (vt);
 509
 510         SEAT_CLASS (seat_unity_parent_class)->set_active_session (seat, session);
 511         return;
 512     }
 513
 514     if (session == SEAT_UNITY (seat)->priv->active_session)
 515         return;
 516     SEAT_UNITY (seat)->priv->active_session = g_object_ref (session);
 517
 518     display_server = session_get_display_server (session);
 519     if (SEAT_UNITY (seat)->priv->active_display_server != display_server)
 520     {
 521         const gchar *id;
 522
 523         SEAT_UNITY (seat)->priv->active_display_server = g_object_ref (display_server);
 524         id = x_server_local_get_mir_id (X_SERVER_LOCAL (display_server));
 525
 526         g_debug ("Switching to Mir session %s", id);
 527         write_message (SEAT_UNITY (seat), USC_MESSAGE_SET_ACTIVE_SESSION, (const guint8 *) id, strlen (id));
 528     }
 529
 530     SEAT_CLASS (seat_unity_parent_class)->set_active_session (seat, session);
 531 }
 532
 533 static Session *
 534 seat_unity_get_active_session (Seat *seat)
 535 {
 536     if (SEAT_UNITY (seat)->priv->use_vt_switching)
 537     {
 538         gint vt;
 539         GList *link;
 540         vt = vt_get_active ();
 541         if (vt < 0)
 542             return NULL;
 543
 544         for (link = seat_get_sessions (seat); link; link = link->next)
 545         {
 546             Session *session = link->data;
 547             if (display_server_get_vt (session_get_display_server (session)) == vt)
 548                 return session;
 549         }
 550
 551         return NULL;
 552     }
 553
 554     return SEAT_UNITY (seat)->priv->active_session;
 555 }
 556
 557 static void
 558 seat_unity_run_script (Seat *seat, DisplayServer *display_server, Process *script)
 559 {
 560     const gchar *path;
 561     XServerLocal *x_server;
 562
 563     x_server = X_SERVER_LOCAL (display_server);
 564     path = x_server_local_get_authority_file_path (x_server);
 565     process_set_env (script, "DISPLAY", x_server_get_address (X_SERVER (x_server)));
 566     process_set_env (script, "XAUTHORITY", path);
 567
 568     SEAT_CLASS (seat_unity_parent_class)->run_script (seat, display_server, script);
 569 }
 570
 571 static void
 572 seat_unity_stop (Seat *seat)
 573 {
 574     /* Stop the compositor first */
 575     if (process_get_is_running (SEAT_UNITY (seat)->priv->compositor_process))
 576     {
 577         process_stop (SEAT_UNITY (seat)->priv->compositor_process);
 578         return;
 579     }
 580
 581     SEAT_CLASS (seat_unity_parent_class)->stop (seat);
 582 }
 583
 584 static void
 585 seat_unity_init (SeatUnity *seat)
 586 {
 587     seat->priv = G_TYPE_INSTANCE_GET_PRIVATE (seat, SEAT_UNITY_TYPE, SeatUnityPrivate);
 588     seat->priv->vt = -1;
 589     seat->priv->compositor_process = process_new ();
 590 }
 591
 592 static void
 593 seat_unity_finalize (GObject *object)
 594 {
 595     SeatUnity *seat = SEAT_UNITY (object);
 596
 597     if (seat->priv->vt >= 0)
 598         vt_unref (seat->priv->vt);
 599     g_free (seat->priv->log_file);
 600     g_free (seat->priv->mir_socket_filename);
 601     close (seat->priv->to_compositor_pipe[0]);
 602     close (seat->priv->to_compositor_pipe[1]);
 603     close (seat->priv->from_compositor_pipe[0]);
 604     close (seat->priv->from_compositor_pipe[1]);
 605     g_io_channel_unref (seat->priv->from_compositor_channel);
 606     g_free (seat->priv->read_buffer);
 607     g_object_unref (seat->priv->compositor_process);
 608     if (seat->priv->active_session)
 609         g_object_unref (seat->priv->active_session);
 610     if (seat->priv->active_display_server)
 611         g_object_unref (seat->priv->active_display_server);
 612
 613     G_OBJECT_CLASS (seat_unity_parent_class)->finalize (object);
 614 }
 615
 616 static void
 617 seat_unity_class_init (SeatUnityClass *klass)
 618 {
 619     GObjectClass *object_class = G_OBJECT_CLASS (klass);
 620     SeatClass *seat_class = SEAT_CLASS (klass);
 621
 622     object_class->finalize = seat_unity_finalize;
 623     seat_class->setup = seat_unity_setup;
 624     seat_class->start = seat_unity_start;
 625     seat_class->create_display_server = seat_unity_create_display_server;
 626     seat_class->create_greeter_session = seat_unity_create_greeter_session;
 627     seat_class->create_session = seat_unity_create_session;
 628     seat_class->set_active_session = seat_unity_set_active_session;
 629     seat_class->get_active_session = seat_unity_get_active_session;
 630     seat_class->run_script = seat_unity_run_script;
 631     seat_class->stop = seat_unity_stop;
 632
 633     g_type_class_add_private (klass, sizeof (SeatUnityPrivate));
 634 }