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