bus/at-spi-bus-launcher.c

   1 /* -*- mode: c; c-basic-offset: 2; indent-tabs-mode: nil; -*-
   2  *
   3  * at-spi-bus-launcher: Manage the a11y bus as a child process
   4  *
   5  * Copyright 2011 Red Hat, Inc.
   6  *
   7  * This library is free software; you can redistribute it and/or
   8  * modify it under the terms of the GNU Library General Public
   9  * License as published by the Free Software Foundation; either
  10  * version 2 of the License, or (at your option) any later version.
  11  *
  12  * This library is distributed in the hope that it will be useful,
  13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15  * Library General Public License for more details.
  16  *
  17  * You should have received a copy of the GNU Library General Public
  18  * License along with this library; if not, write to the
  19  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  20  * Boston, MA 02111-1307, USA.
  21  */
  22
  23 #include "config.h"
  24
  25 #include <unistd.h>
  26 #include <string.h>
  27 #include <signal.h>
  28 #include <sys/wait.h>
  29 #include <errno.h>
  30 #include <stdio.h>
  31
  32 #include <gio/gio.h>
  33 #ifdef HAVE_X11
  34 #include <X11/Xlib.h>
  35 #include <X11/Xatom.h>
  36 #endif
  37
  38 #define APP_CONTROL_OPERATION_SCREEN_READ "http://tizen.org/appcontrol/operation/read_screen"
  39 #include <appsvc.h>
  40 #include <vconf.h>
  41
  42 //uncomment if you want debug
  43 //#ifndef TIZEN_ENGINEER_MODE
  44 //#define TIZEN_ENGINEER_MODE
  45 //#endif
  46 #ifdef LOG_TAG
  47 #undef LOG_TAG
  48 #endif
  49
  50 #define LOG_TAG "ATSPI_BUS_LAUNCHER"
  51
  52 #include <dlog.h>
  53 #include <aul.h>
  54
  55 //uncomment this if you want log suring startup
  56 //seems like dlog is not working at startup time
  57 #define ATSPI_BUS_LAUNCHER_LOG_TO_FILE
  58
  59 #ifdef ATSPI_BUS_LAUNCHER_LOG_TO_FILE
  60 FILE *log_file;
  61 #ifdef LOGD
  62 #undef LOGD
  63 #endif
  64 #define LOGD(arg...) do {if (log_file) {fprintf(log_file, ##arg);fprintf(log_file, "\n"); fflush(log_file);}} while(0)
  65 #endif
  66
  67
  68 typedef enum {
  69   A11Y_BUS_STATE_IDLE = 0,
  70   A11Y_BUS_STATE_READING_ADDRESS,
  71   A11Y_BUS_STATE_RUNNING,
  72   A11Y_BUS_STATE_ERROR
  73 } A11yBusState;
  74
  75 typedef struct {
  76   GMainLoop *loop;
  77   gboolean launch_immediately;
  78   gboolean a11y_enabled;
  79   gboolean screen_reader_enabled;
  80   GDBusConnection *session_bus;
  81   GSettings *a11y_schema;
  82   GSettings *interface_schema;
  83
  84   int launch_screen_reader_repeats;
  85   gboolean screen_reader_needed;
  86   int pid;
  87
  88   A11yBusState state;
  89
  90   /* -1 == error, 0 == pending, > 0 == running */
  91   int a11y_bus_pid;
  92   char *a11y_bus_address;
  93   int pipefd[2];
  94   char *a11y_launch_error_message;
  95 } A11yBusLauncher;
  96
  97 static A11yBusLauncher *_global_app = NULL;
  98
  99 static const gchar introspection_xml[] =
 100   "<node>"
 101   "  <interface name='org.a11y.Bus'>"
 102   "    <method name='GetAddress'>"
 103   "      <arg type='s' name='address' direction='out'/>"
 104   "    </method>"
 105   "  </interface>"
 106   "<interface name='org.a11y.Status'>"
 107   "<property name='IsEnabled' type='b' access='readwrite'/>"
 108   "<property name='ScreenReaderEnabled' type='b' access='readwrite'/>"
 109   "</interface>"
 110   "</node>";
 111 static GDBusNodeInfo *introspection_data = NULL;
 112
 113 static void
 114 setup_bus_child (gpointer data)
 115 {
 116   A11yBusLauncher *app = data;
 117   (void) app;
 118
 119   close (app->pipefd[0]);
 120   dup2 (app->pipefd[1], 3);
 121   close (app->pipefd[1]);
 122
 123   /* On Linux, tell the bus process to exit if this process goes away */
 124 #ifdef __linux
 125 #include <sys/prctl.h>
 126   prctl (PR_SET_PDEATHSIG, 15);
 127 #endif
 128 }
 129
 130 /**
 131  * unix_read_all_fd_to_string:
 132  *
 133  * Read all data from a file descriptor to a C string buffer.
 134  */
 135 static gboolean
 136 unix_read_all_fd_to_string (int      fd,
 137                             char    *buf,
 138                             ssize_t  max_bytes)
 139 {
 140   ssize_t bytes_read;
 141
 142   while (max_bytes > 1 && (bytes_read = read (fd, buf, MAX (4096, max_bytes - 1))))
 143     {
 144       if (bytes_read < 0)
 145         return FALSE;
 146       buf += bytes_read;
 147       max_bytes -= bytes_read;
 148     }
 149   *buf = '\0';
 150   return TRUE;
 151 }
 152
 153 static void
 154 on_bus_exited (GPid     pid,
 155                gint     status,
 156                gpointer data)
 157 {
 158   A11yBusLauncher *app = data;
 159
 160   app->a11y_bus_pid = -1;
 161   app->state = A11Y_BUS_STATE_ERROR;
 162   if (app->a11y_launch_error_message == NULL)
 163     {
 164       if (WIFEXITED (status))
 165         app->a11y_launch_error_message = g_strdup_printf ("Bus exited with code %d", WEXITSTATUS (status));
 166       else if (WIFSIGNALED (status))
 167         app->a11y_launch_error_message = g_strdup_printf ("Bus killed by signal %d", WTERMSIG (status));
 168       else if (WIFSTOPPED (status))
 169         app->a11y_launch_error_message = g_strdup_printf ("Bus stopped by signal %d", WSTOPSIG (status));
 170     }
 171   g_main_loop_quit (app->loop);
 172 }
 173
 174 static gboolean
 175 ensure_a11y_bus (A11yBusLauncher *app)
 176 {
 177   GPid pid;
 178   char *argv[] = { DBUS_DAEMON, NULL, "--nofork", "--print-address", "3", NULL };
 179   char addr_buf[2048];
 180   GError *error = NULL;
 181
 182   if (app->a11y_bus_pid != 0)
 183     return FALSE;
 184
 185   argv[1] = g_strdup_printf ("--config-file=%s/at-spi2/accessibility.conf", SYSCONFDIR);
 186
 187   if (pipe (app->pipefd) < 0)
 188     g_error ("Failed to create pipe: %s", strerror (errno));
 189
 190   if (!g_spawn_async (NULL,
 191                       argv,
 192                       NULL,
 193                       G_SPAWN_SEARCH_PATH | G_SPAWN_DO_NOT_REAP_CHILD,
 194                       setup_bus_child,
 195                       app,
 196                       &pid,
 197                       &error))
 198     {
 199       app->a11y_bus_pid = -1;
 200       app->a11y_launch_error_message = g_strdup (error->message);
 201       g_clear_error (&error);
 202       goto error;
 203     }
 204
 205   close (app->pipefd[1]);
 206   app->pipefd[1] = -1;
 207
 208   g_child_watch_add (pid, on_bus_exited, app);
 209
 210   app->state = A11Y_BUS_STATE_READING_ADDRESS;
 211   app->a11y_bus_pid = pid;
 212   LOGD("Launched a11y bus, child is %ld", (long) pid);
 213   if (!unix_read_all_fd_to_string (app->pipefd[0], addr_buf, sizeof (addr_buf)))
 214     {
 215       app->a11y_launch_error_message = g_strdup_printf ("Failed to read address: %s", strerror (errno));
 216       kill (app->a11y_bus_pid, SIGTERM);
 217       goto error;
 218     }
 219   close (app->pipefd[0]);
 220   app->pipefd[0] = -1;
 221   app->state = A11Y_BUS_STATE_RUNNING;
 222
 223   /* Trim the trailing newline */
 224   app->a11y_bus_address = g_strchomp (g_strdup (addr_buf));
 225   LOGD("a11y bus address: %s", app->a11y_bus_address);
 226
 227 #ifdef HAVE_X11
 228   {
 229     Display *display = XOpenDisplay (NULL);
 230     if (display)
 231       {
 232         Atom bus_address_atom = XInternAtom (display, "AT_SPI_BUS", False);
 233         XChangeProperty (display,
 234                          XDefaultRootWindow (display),
 235                          bus_address_atom,
 236                          XA_STRING, 8, PropModeReplace,
 237                          (guchar *) app->a11y_bus_address, strlen (app->a11y_bus_address));
 238         XFlush (display);
 239         XCloseDisplay (display);
 240       }
 241   }
 242 #endif
 243
 244   return TRUE;
 245
 246  error:
 247   close (app->pipefd[0]);
 248   close (app->pipefd[1]);
 249   app->state = A11Y_BUS_STATE_ERROR;
 250
 251   return FALSE;
 252 }
 253
 254 static void
 255 handle_method_call (GDBusConnection       *connection,
 256                     const gchar           *sender,
 257                     const gchar           *object_path,
 258                     const gchar           *interface_name,
 259                     const gchar           *method_name,
 260                     GVariant              *parameters,
 261                     GDBusMethodInvocation *invocation,
 262                     gpointer               user_data)
 263 {
 264   A11yBusLauncher *app = user_data;
 265
 266   if (g_strcmp0 (method_name, "GetAddress") == 0)
 267     {
 268       ensure_a11y_bus (app);
 269       if (app->a11y_bus_pid > 0)
 270         g_dbus_method_invocation_return_value (invocation,
 271                                                g_variant_new ("(s)", app->a11y_bus_address));
 272       else
 273         g_dbus_method_invocation_return_dbus_error (invocation,
 274                                                     "org.a11y.Bus.Error",
 275                                                     app->a11y_launch_error_message);
 276     }
 277 }
 278
 279 static GVariant *
 280 handle_get_property  (GDBusConnection       *connection,
 281                       const gchar           *sender,
 282                       const gchar           *object_path,
 283                       const gchar           *interface_name,
 284                       const gchar           *property_name,
 285                     GError **error,
 286                     gpointer               user_data)
 287 {
 288   A11yBusLauncher *app = user_data;
 289
 290   if (g_strcmp0 (property_name, "IsEnabled") == 0)
 291     return g_variant_new ("b", app->a11y_enabled);
 292   else if (g_strcmp0 (property_name, "ScreenReaderEnabled") == 0)
 293     return g_variant_new ("b", app->screen_reader_enabled);
 294   else
 295     return NULL;
 296 }
 297
 298 static void
 299 handle_a11y_enabled_change (A11yBusLauncher *app, gboolean enabled,
 300                                gboolean notify_gsettings)
 301 {
 302   GVariantBuilder builder;
 303   GVariantBuilder invalidated_builder;
 304
 305   if (enabled == app->a11y_enabled)
 306     return;
 307
 308   app->a11y_enabled = enabled;
 309
 310   if (notify_gsettings && app->interface_schema)
 311     {
 312       g_settings_set_boolean (app->interface_schema, "toolkit-accessibility",
 313                               enabled);
 314       g_settings_sync ();
 315     }
 316
 317   g_variant_builder_init (&builder, G_VARIANT_TYPE_ARRAY);
 318   g_variant_builder_init (&invalidated_builder, G_VARIANT_TYPE ("as"));
 319   g_variant_builder_add (&builder, "{sv}", "IsEnabled",
 320                          g_variant_new_boolean (enabled));
 321
 322   g_dbus_connection_emit_signal (app->session_bus, NULL, "/org/a11y/bus",
 323                                  "org.freedesktop.DBus.Properties",
 324                                  "PropertiesChanged",
 325                                  g_variant_new ("(sa{sv}as)", "org.a11y.Status",
 326                                                 &builder,
 327                                                 &invalidated_builder),
 328                                  NULL);
 329 }
 330
 331 static void
 332 handle_screen_reader_enabled_change (A11yBusLauncher *app, gboolean enabled,
 333                                gboolean notify_gsettings)
 334 {
 335   GVariantBuilder builder;
 336   GVariantBuilder invalidated_builder;
 337
 338   if (enabled == app->screen_reader_enabled)
 339     return;
 340
 341   /* If the screen reader is being enabled, we should enable accessibility
 342    * if it isn't enabled already */
 343   if (enabled)
 344     handle_a11y_enabled_change (app, enabled, notify_gsettings);
 345
 346   app->screen_reader_enabled = enabled;
 347
 348   if (notify_gsettings && app->a11y_schema)
 349     {
 350       g_settings_set_boolean (app->a11y_schema, "screen-reader-enabled",
 351                               enabled);
 352       g_settings_sync ();
 353     }
 354
 355   g_variant_builder_init (&builder, G_VARIANT_TYPE_ARRAY);
 356   g_variant_builder_init (&invalidated_builder, G_VARIANT_TYPE ("as"));
 357   g_variant_builder_add (&builder, "{sv}", "ScreenReaderEnabled",
 358                          g_variant_new_boolean (enabled));
 359
 360   g_dbus_connection_emit_signal (app->session_bus, NULL, "/org/a11y/bus",
 361                                  "org.freedesktop.DBus.Properties",
 362                                  "PropertiesChanged",
 363                                  g_variant_new ("(sa{sv}as)", "org.a11y.Status",
 364                                                 &builder,
 365                                                 &invalidated_builder),
 366                                  NULL);
 367 }
 368
 369 static gboolean
 370 handle_set_property  (GDBusConnection       *connection,
 371                       const gchar           *sender,
 372                       const gchar           *object_path,
 373                       const gchar           *interface_name,
 374                       const gchar           *property_name,
 375                       GVariant *value,
 376                     GError **error,
 377                     gpointer               user_data)
 378 {
 379   A11yBusLauncher *app = user_data;
 380   const gchar *type = g_variant_get_type_string (value);
 381   gboolean enabled;
 382
 383   if (g_strcmp0 (type, "b") != 0)
 384     {
 385       g_set_error (error, G_DBUS_ERROR, G_DBUS_ERROR_INVALID_ARGS,
 386                        "org.a11y.Status.%s expects a boolean but got %s", property_name, type);
 387       return FALSE;
 388     }
 389
 390   enabled = g_variant_get_boolean (value);
 391
 392   if (g_strcmp0 (property_name, "IsEnabled") == 0)
 393     {
 394       handle_a11y_enabled_change (app, enabled, TRUE);
 395       return TRUE;
 396     }
 397   else if (g_strcmp0 (property_name, "ScreenReaderEnabled") == 0)
 398     {
 399       handle_screen_reader_enabled_change (app, enabled, TRUE);
 400       return TRUE;
 401     }
 402   else
 403     {
 404       g_set_error (error, G_DBUS_ERROR, G_DBUS_ERROR_INVALID_ARGS,
 405                        "Unknown property '%s'", property_name);
 406       return FALSE;
 407     }
 408 }
 409
 410 static const GDBusInterfaceVTable bus_vtable =
 411 {
 412   handle_method_call,
 413   NULL, /* handle_get_property, */
 414   NULL  /* handle_set_property */
 415 };
 416
 417 static const GDBusInterfaceVTable status_vtable =
 418 {
 419   NULL, /* handle_method_call */
 420   handle_get_property,
 421   handle_set_property
 422 };
 423
 424 static void
 425 on_bus_acquired (GDBusConnection *connection,
 426                  const gchar     *name,
 427                  gpointer         user_data)
 428 {
 429   A11yBusLauncher *app = user_data;
 430   GError *error;
 431   guint registration_id;
 432
 433   if (connection == NULL)
 434     {
 435       g_main_loop_quit (app->loop);
 436       return;
 437     }
 438   app->session_bus = connection;
 439
 440   if (app->launch_immediately)
 441     {
 442       ensure_a11y_bus (app);
 443       if (app->state == A11Y_BUS_STATE_ERROR)
 444         {
 445           g_main_loop_quit (app->loop);
 446           return;
 447         }
 448     }
 449
 450   error = NULL;
 451   registration_id = g_dbus_connection_register_object (connection,
 452                                                        "/org/a11y/bus",
 453                                                        introspection_data->interfaces[0],
 454                                                        &bus_vtable,
 455                                                        _global_app,
 456                                                        NULL,
 457                                                        &error);
 458   if (registration_id == 0)
 459     {
 460       g_error ("%s", error->message);
 461       g_clear_error (&error);
 462     }
 463
 464   g_dbus_connection_register_object (connection,
 465                                      "/org/a11y/bus",
 466                                      introspection_data->interfaces[1],
 467                                      &status_vtable,
 468                                      _global_app,
 469                                      NULL,
 470                                      NULL);
 471 }
 472
 473 static void
 474 on_name_lost (GDBusConnection *connection,
 475               const gchar     *name,
 476               gpointer         user_data)
 477 {
 478   A11yBusLauncher *app = user_data;
 479   if (app->session_bus == NULL
 480       && connection == NULL
 481       && app->a11y_launch_error_message == NULL)
 482     app->a11y_launch_error_message = g_strdup ("Failed to connect to session bus");
 483   g_main_loop_quit (app->loop);
 484 }
 485
 486 static void
 487 on_name_acquired (GDBusConnection *connection,
 488                   const gchar     *name,
 489                   gpointer         user_data)
 490 {
 491   A11yBusLauncher *app = user_data;
 492   (void) app;
 493 }
 494
 495 static int sigterm_pipefd[2];
 496
 497 static void
 498 sigterm_handler (int signum)
 499 {
 500   write (sigterm_pipefd[1], "X", 1);
 501 }
 502
 503 static gboolean
 504 on_sigterm_pipe (GIOChannel  *channel,
 505                  GIOCondition condition,
 506                  gpointer     data)
 507 {
 508   A11yBusLauncher *app = data;
 509
 510   g_main_loop_quit (app->loop);
 511
 512   return FALSE;
 513 }
 514
 515 static void
 516 init_sigterm_handling (A11yBusLauncher *app)
 517 {
 518   GIOChannel *sigterm_channel;
 519
 520   if (pipe (sigterm_pipefd) < 0)
 521     g_error ("Failed to create pipe: %s", strerror (errno));
 522   signal (SIGTERM, sigterm_handler);
 523
 524   sigterm_channel = g_io_channel_unix_new (sigterm_pipefd[0]);
 525   g_io_add_watch (sigterm_channel,
 526                   G_IO_IN | G_IO_ERR | G_IO_HUP,
 527                   on_sigterm_pipe,
 528                   app);
 529 }
 530
 531 static gboolean
 532 already_running ()
 533 {
 534 #ifdef HAVE_X11
 535   Atom AT_SPI_BUS;
 536   Atom actual_type;
 537   Display *bridge_display;
 538   int actual_format;
 539   unsigned char *data = NULL;
 540   unsigned long nitems;
 541   unsigned long leftover;
 542   gboolean result = FALSE;
 543
 544   bridge_display = XOpenDisplay (NULL);
 545   if (!bridge_display)
 546               return FALSE;
 547
 548   AT_SPI_BUS = XInternAtom (bridge_display, "AT_SPI_BUS", False);
 549   XGetWindowProperty (bridge_display,
 550                       XDefaultRootWindow (bridge_display),
 551                       AT_SPI_BUS, 0L,
 552                       (long) BUFSIZ, False,
 553                       (Atom) 31, &actual_type, &actual_format,
 554                       &nitems, &leftover, &data);
 555
 556   if (data)
 557   {
 558     GDBusConnection *bus;
 559     bus = g_dbus_connection_new_for_address_sync ((const gchar *)data, 0,
 560                                                   NULL, NULL, NULL);
 561     if (bus != NULL)
 562       {
 563         result = TRUE;
 564         g_object_unref (bus);
 565       }
 566   }
 567
 568   XCloseDisplay (bridge_display);
 569   return result;
 570 #else
 571   return FALSE;
 572 #endif
 573 }
 574
 575 static GSettings *
 576 get_schema (const gchar *name)
 577 {
 578   const char * const *schemas = NULL;
 579   gint i;
 580
 581   schemas = g_settings_list_schemas ();
 582   for (i = 0; schemas[i]; i++)
 583   {
 584     if (!strcmp (schemas[i], name))
 585       return g_settings_new (schemas[i]);
 586   }
 587
 588   return NULL;
 589 }
 590
 591 static void
 592 gsettings_key_changed (GSettings *gsettings, const gchar *key, void *user_data)
 593 {
 594   gboolean new_val = g_settings_get_boolean (gsettings, key);
 595   A11yBusLauncher *app = user_data;
 596
 597   if (!strcmp (key, "toolkit-accessibility"))
 598     handle_a11y_enabled_change (_global_app, new_val, FALSE);
 599   else if (!strcmp (key, "screen-reader-enabled"))
 600     handle_screen_reader_enabled_change (_global_app, new_val, FALSE);
 601 }
 602
 603 static gboolean
 604 _launch_screen_reader(gpointer user_data)
 605 {
 606    A11yBusLauncher *bl = user_data;
 607    LOGD("Launching screen reader");
 608
 609    bundle *kb = NULL;
 610    gboolean ret = FALSE;
 611
 612    kb = bundle_create();
 613
 614    if (kb == NULL)
 615      {
 616         LOGD("Can't create bundle");
 617         return FALSE;
 618      }
 619    int operation_error = appsvc_set_operation(kb, APP_CONTROL_OPERATION_SCREEN_READ);
 620    LOGD("appsvc_set_operation: %i", operation_error);
 621
 622    bl->pid = appsvc_run_service(kb, 0, NULL, NULL);
 623
 624    if (bl->pid > 0)
 625      {
 626         LOGD("Screen reader launched with pid: %i", bl->pid);
 627         ret = TRUE;
 628      }
 629    else
 630      {
 631         LOGD("Can't start screen-reader - error code: %i", bl->pid);
 632      }
 633
 634
 635    bundle_free(kb);
 636    return ret;
 637 }
 638
 639 static gboolean
 640 _launch_screen_reader_repeat_until_success(gpointer user_data) {
 641     A11yBusLauncher *bl = user_data;
 642
 643     if (bl->launch_screen_reader_repeats > 100 || bl->pid > 0)
 644       {
 645          //do not try anymore
 646          return FALSE;
 647       }
 648
 649     gboolean ret = _launch_screen_reader(user_data);
 650
 651     if (ret)
 652       {
 653          //we managed to
 654          bl->launch_screen_reader_repeats = 0;
 655          return FALSE;
 656       }
 657     //try again
 658     return TRUE;
 659 }
 660
 661 static gboolean
 662 _terminate_screen_reader(A11yBusLauncher *bl)
 663 {
 664    LOGD("Terminating screen reader");
 665    int ret;
 666    int ret_aul;
 667    if (bl->pid <= 0)
 668      return FALSE;
 669
 670
 671    int status = aul_app_get_status_bypid(bl->pid);
 672
 673    if (status < 0)
 674      {
 675        LOGD("App with pid %d already terminated", bl->pid);
 676        bl->pid = 0;
 677        return TRUE;
 678      }
 679
 680    LOGD("terminate process with pid %d", bl->pid);
 681    ret_aul = aul_terminate_pid(bl->pid);
 682    if (ret_aul >= 0)
 683      {
 684         LOGD("Terminating with aul_terminate_pid: return is %d", ret_aul);
 685         bl->pid = 0;
 686         return TRUE;
 687      }
 688    else
 689      LOGD("aul_terminate_pid failed: return is %d", ret_aul);
 690
 691    LOGD("Unable to terminate process using aul api. Sending SIGTERM signal");
 692    ret = kill(bl->pid, SIGTERM);
 693    if (!ret)
 694      {
 695         bl->pid = 0;
 696         return TRUE;
 697      }
 698
 699    LOGD("Unable to terminate process: %d with api or signal.", bl->pid);
 700    return FALSE;
 701 }
 702
 703 void screen_reader_cb(keynode_t *node, void *user_data)
 704 {
 705    A11yBusLauncher *bl = user_data;
 706    int ret;
 707
 708    ret = vconf_keynode_get_bool(node);
 709    LOGD("vconf_keynode_get_bool(node): %i", ret);
 710    if (ret < 0)
 711      return;
 712
 713    //check if process really exists (e.g didn't crash)
 714    if (bl->pid > 0)
 715      {
 716         int err = kill(bl->pid,0);
 717         //process doesn't exist
 718         if (err == ESRCH)
 719           bl->pid = 0;
 720      }
 721
 722    bl->screen_reader_needed = ret;
 723    LOGD("bl->screen_reader_needed: %i, bl->pid: %i", ret, bl->pid);
 724    if (!bl->screen_reader_needed && (bl->pid > 0))
 725      _terminate_screen_reader(bl);
 726    else if (bl->screen_reader_needed && (bl->pid <= 0))
 727      _launch_screen_reader(bl);
 728 }
 729
 730 int
 731 main (int    argc,
 732       char **argv)
 733 {
 734 #ifdef ATSPI_BUS_LAUNCHER_LOG_TO_FILE
 735   log_file = fopen("/tmp/at-spi-bus-launcher.log", "a");
 736 #endif
 737
 738   LOGD("Starting atspi bus launcher");
 739   GError *error = NULL;
 740   GMainLoop *loop;
 741   GDBusConnection *session_bus;
 742   int name_owner_id;
 743   gboolean a11y_set = FALSE;
 744   gboolean screen_reader_set = FALSE;
 745   gint i;
 746
 747   if (already_running ())
 748     {
 749        LOGD("atspi bus launcher is already running");
 750        return 0;
 751     }
 752
 753   _global_app = g_slice_new0 (A11yBusLauncher);
 754   _global_app->loop = g_main_loop_new (NULL, FALSE);
 755   _global_app->launch_screen_reader_repeats = 0;
 756
 757   for (i = 1; i < argc; i++)
 758     {
 759       if (!strcmp (argv[i], "--launch-immediately"))
 760         _global_app->launch_immediately = TRUE;
 761       else if (sscanf (argv[i], "--a11y=%d", &_global_app->a11y_enabled) == 2)
 762         a11y_set = TRUE;
 763       else if (sscanf (argv[i], "--screen-reader=%d",
 764                        &_global_app->screen_reader_enabled) == 2)
 765         screen_reader_set = TRUE;
 766     else
 767       g_error ("usage: %s [--launch-immediately] [--a11y=0|1] [--screen-reader=0|1]", argv[0]);
 768     }
 769
 770   _global_app->interface_schema = get_schema ("org.gnome.desktop.interface");
 771   _global_app->a11y_schema = get_schema ("org.gnome.desktop.a11y.applications");
 772
 773   if (!a11y_set)
 774     {
 775       _global_app->a11y_enabled = _global_app->interface_schema
 776                                   ? g_settings_get_boolean (_global_app->interface_schema, "toolkit-accessibility")
 777                                   : _global_app->launch_immediately;
 778     }
 779
 780   if (!screen_reader_set)
 781     {
 782       _global_app->screen_reader_enabled = _global_app->a11y_schema
 783                                   ? g_settings_get_boolean (_global_app->a11y_schema, "screen-reader-enabled")
 784                                   : FALSE;
 785     }
 786
 787   if (_global_app->interface_schema)
 788     g_signal_connect (_global_app->interface_schema,
 789                       "changed::toolkit-accessibility",
 790                       G_CALLBACK (gsettings_key_changed), _global_app);
 791
 792   if (_global_app->a11y_schema)
 793     g_signal_connect (_global_app->a11y_schema,
 794                       "changed::screen-reader-enabled",
 795                       G_CALLBACK (gsettings_key_changed), _global_app);
 796
 797   init_sigterm_handling (_global_app);
 798
 799   introspection_data = g_dbus_node_info_new_for_xml (introspection_xml, NULL);
 800   g_assert (introspection_data != NULL);
 801
 802   name_owner_id = g_bus_own_name (G_BUS_TYPE_SESSION,
 803                                   "org.a11y.Bus",
 804                                   G_BUS_NAME_OWNER_FLAGS_ALLOW_REPLACEMENT,
 805                                   on_bus_acquired,
 806                                   on_name_acquired,
 807                                   on_name_lost,
 808                                   _global_app,
 809                                   NULL);
 810
 811   int ret = vconf_get_bool(VCONFKEY_SETAPPL_ACCESSIBILITY_TTS, &_global_app->screen_reader_needed);
 812   if (ret != 0)
 813     {
 814       LOGD("Could not read VCONFKEY_SETAPPL_ACCESSIBILITY_TTS key value.\n");
 815       return FALSE;
 816     }
 817   ret = vconf_notify_key_changed(VCONFKEY_SETAPPL_ACCESSIBILITY_TTS, screen_reader_cb, _global_app);
 818   if(ret != 0)
 819     {
 820       LOGD("Could not add information level callback\n");
 821       return FALSE;
 822     }
 823   if (_global_app->screen_reader_needed)
 824     g_timeout_add_seconds(2,_launch_screen_reader_repeat_until_success, _global_app);
 825
 826   g_main_loop_run (_global_app->loop);
 827
 828   if (_global_app->a11y_bus_pid > 0)
 829     kill (_global_app->a11y_bus_pid, SIGTERM);
 830
 831   /* Clear the X property if our bus is gone; in the case where e.g.
 832    * GDM is launching a login on an X server it was using before,
 833    * we don't want early login processes to pick up the stale address.
 834    */
 835 #ifdef HAVE_X11
 836   {
 837     Display *display = XOpenDisplay (NULL);
 838     if (display)
 839       {
 840         Atom bus_address_atom = XInternAtom (display, "AT_SPI_BUS", False);
 841         XDeleteProperty (display,
 842                          XDefaultRootWindow (display),
 843                          bus_address_atom);
 844
 845         XFlush (display);
 846         XCloseDisplay (display);
 847       }
 848   }
 849 #endif
 850
 851   if (_global_app->a11y_launch_error_message)
 852     {
 853       g_printerr ("Failed to launch bus: %s", _global_app->a11y_launch_error_message);
 854       return 1;
 855     }
 856   return 0;
 857 }