1 /* -*- mode: c; c-basic-offset: 2; indent-tabs-mode: nil; -*-
3 * at-spi-bus-launcher: Manage the a11y bus as a child process
5 * Copyright 2011 Red Hat, Inc.
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.
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.
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.
35 #include <X11/Xatom.h>
38 #define APP_CONTROL_OPERATION_SCREEN_READ "http://tizen.org/appcontrol/operation/read_screen"
45 A11Y_BUS_STATE_IDLE = 0,
46 A11Y_BUS_STATE_READING_ADDRESS,
47 A11Y_BUS_STATE_RUNNING,
53 gboolean launch_immediately;
54 gboolean a11y_enabled;
55 gboolean screen_reader_enabled;
56 GDBusConnection *session_bus;
57 GSettings *a11y_schema;
58 GSettings *interface_schema;
60 gboolean screen_reader_needed;
65 /* -1 == error, 0 == pending, > 0 == running */
67 char *a11y_bus_address;
69 char *a11y_launch_error_message;
72 static A11yBusLauncher *_global_app = NULL;
74 static const gchar introspection_xml[] =
76 " <interface name='org.a11y.Bus'>"
77 " <method name='GetAddress'>"
78 " <arg type='s' name='address' direction='out'/>"
81 "<interface name='org.a11y.Status'>"
82 "<property name='IsEnabled' type='b' access='readwrite'/>"
83 "<property name='ScreenReaderEnabled' type='b' access='readwrite'/>"
86 static GDBusNodeInfo *introspection_data = NULL;
89 setup_bus_child (gpointer data)
91 A11yBusLauncher *app = data;
94 close (app->pipefd[0]);
95 dup2 (app->pipefd[1], 3);
96 close (app->pipefd[1]);
98 /* On Linux, tell the bus process to exit if this process goes away */
100 #include <sys/prctl.h>
101 prctl (PR_SET_PDEATHSIG, 15);
106 * unix_read_all_fd_to_string:
108 * Read all data from a file descriptor to a C string buffer.
111 unix_read_all_fd_to_string (int fd,
117 while (max_bytes > 1 && (bytes_read = read (fd, buf, MAX (4096, max_bytes - 1))))
122 max_bytes -= bytes_read;
129 on_bus_exited (GPid pid,
133 A11yBusLauncher *app = data;
135 app->a11y_bus_pid = -1;
136 app->state = A11Y_BUS_STATE_ERROR;
137 if (app->a11y_launch_error_message == NULL)
139 if (WIFEXITED (status))
140 app->a11y_launch_error_message = g_strdup_printf ("Bus exited with code %d", WEXITSTATUS (status));
141 else if (WIFSIGNALED (status))
142 app->a11y_launch_error_message = g_strdup_printf ("Bus killed by signal %d", WTERMSIG (status));
143 else if (WIFSTOPPED (status))
144 app->a11y_launch_error_message = g_strdup_printf ("Bus stopped by signal %d", WSTOPSIG (status));
146 g_main_loop_quit (app->loop);
150 ensure_a11y_bus (A11yBusLauncher *app)
153 char *argv[] = { DBUS_DAEMON, NULL, "--nofork", "--print-address", "3", NULL };
155 GError *error = NULL;
157 if (app->a11y_bus_pid != 0)
160 argv[1] = g_strdup_printf ("--config-file=%s/at-spi2/accessibility.conf", SYSCONFDIR);
162 if (pipe (app->pipefd) < 0)
163 g_error ("Failed to create pipe: %s", strerror (errno));
165 if (!g_spawn_async (NULL,
168 G_SPAWN_SEARCH_PATH | G_SPAWN_DO_NOT_REAP_CHILD,
174 app->a11y_bus_pid = -1;
175 app->a11y_launch_error_message = g_strdup (error->message);
176 g_clear_error (&error);
180 close (app->pipefd[1]);
183 g_child_watch_add (pid, on_bus_exited, app);
185 app->state = A11Y_BUS_STATE_READING_ADDRESS;
186 app->a11y_bus_pid = pid;
187 g_debug ("Launched a11y bus, child is %ld", (long) pid);
188 if (!unix_read_all_fd_to_string (app->pipefd[0], addr_buf, sizeof (addr_buf)))
190 app->a11y_launch_error_message = g_strdup_printf ("Failed to read address: %s", strerror (errno));
191 kill (app->a11y_bus_pid, SIGTERM);
194 close (app->pipefd[0]);
196 app->state = A11Y_BUS_STATE_RUNNING;
198 /* Trim the trailing newline */
199 app->a11y_bus_address = g_strchomp (g_strdup (addr_buf));
200 g_debug ("a11y bus address: %s", app->a11y_bus_address);
204 Display *display = XOpenDisplay (NULL);
207 Atom bus_address_atom = XInternAtom (display, "AT_SPI_BUS", False);
208 XChangeProperty (display,
209 XDefaultRootWindow (display),
211 XA_STRING, 8, PropModeReplace,
212 (guchar *) app->a11y_bus_address, strlen (app->a11y_bus_address));
214 XCloseDisplay (display);
222 close (app->pipefd[0]);
223 close (app->pipefd[1]);
224 app->state = A11Y_BUS_STATE_ERROR;
230 handle_method_call (GDBusConnection *connection,
232 const gchar *object_path,
233 const gchar *interface_name,
234 const gchar *method_name,
235 GVariant *parameters,
236 GDBusMethodInvocation *invocation,
239 A11yBusLauncher *app = user_data;
241 if (g_strcmp0 (method_name, "GetAddress") == 0)
243 ensure_a11y_bus (app);
244 if (app->a11y_bus_pid > 0)
245 g_dbus_method_invocation_return_value (invocation,
246 g_variant_new ("(s)", app->a11y_bus_address));
248 g_dbus_method_invocation_return_dbus_error (invocation,
249 "org.a11y.Bus.Error",
250 app->a11y_launch_error_message);
255 handle_get_property (GDBusConnection *connection,
257 const gchar *object_path,
258 const gchar *interface_name,
259 const gchar *property_name,
263 A11yBusLauncher *app = user_data;
265 if (g_strcmp0 (property_name, "IsEnabled") == 0)
266 return g_variant_new ("b", app->a11y_enabled);
267 else if (g_strcmp0 (property_name, "ScreenReaderEnabled") == 0)
268 return g_variant_new ("b", app->screen_reader_enabled);
274 handle_a11y_enabled_change (A11yBusLauncher *app, gboolean enabled,
275 gboolean notify_gsettings)
277 GVariantBuilder builder;
278 GVariantBuilder invalidated_builder;
280 if (enabled == app->a11y_enabled)
283 app->a11y_enabled = enabled;
285 if (notify_gsettings && app->interface_schema)
287 g_settings_set_boolean (app->interface_schema, "toolkit-accessibility",
292 g_variant_builder_init (&builder, G_VARIANT_TYPE_ARRAY);
293 g_variant_builder_init (&invalidated_builder, G_VARIANT_TYPE ("as"));
294 g_variant_builder_add (&builder, "{sv}", "IsEnabled",
295 g_variant_new_boolean (enabled));
297 g_dbus_connection_emit_signal (app->session_bus, NULL, "/org/a11y/bus",
298 "org.freedesktop.DBus.Properties",
300 g_variant_new ("(sa{sv}as)", "org.a11y.Status",
302 &invalidated_builder),
307 handle_screen_reader_enabled_change (A11yBusLauncher *app, gboolean enabled,
308 gboolean notify_gsettings)
310 GVariantBuilder builder;
311 GVariantBuilder invalidated_builder;
313 if (enabled == app->screen_reader_enabled)
316 /* If the screen reader is being enabled, we should enable accessibility
317 * if it isn't enabled already */
319 handle_a11y_enabled_change (app, enabled, notify_gsettings);
321 app->screen_reader_enabled = enabled;
323 if (notify_gsettings && app->a11y_schema)
325 g_settings_set_boolean (app->a11y_schema, "screen-reader-enabled",
330 g_variant_builder_init (&builder, G_VARIANT_TYPE_ARRAY);
331 g_variant_builder_init (&invalidated_builder, G_VARIANT_TYPE ("as"));
332 g_variant_builder_add (&builder, "{sv}", "ScreenReaderEnabled",
333 g_variant_new_boolean (enabled));
335 g_dbus_connection_emit_signal (app->session_bus, NULL, "/org/a11y/bus",
336 "org.freedesktop.DBus.Properties",
338 g_variant_new ("(sa{sv}as)", "org.a11y.Status",
340 &invalidated_builder),
345 handle_set_property (GDBusConnection *connection,
347 const gchar *object_path,
348 const gchar *interface_name,
349 const gchar *property_name,
354 A11yBusLauncher *app = user_data;
355 const gchar *type = g_variant_get_type_string (value);
358 if (g_strcmp0 (type, "b") != 0)
360 g_set_error (error, G_DBUS_ERROR, G_DBUS_ERROR_INVALID_ARGS,
361 "org.a11y.Status.%s expects a boolean but got %s", property_name, type);
365 enabled = g_variant_get_boolean (value);
367 if (g_strcmp0 (property_name, "IsEnabled") == 0)
369 handle_a11y_enabled_change (app, enabled, TRUE);
372 else if (g_strcmp0 (property_name, "ScreenReaderEnabled") == 0)
374 handle_screen_reader_enabled_change (app, enabled, TRUE);
379 g_set_error (error, G_DBUS_ERROR, G_DBUS_ERROR_INVALID_ARGS,
380 "Unknown property '%s'", property_name);
385 static const GDBusInterfaceVTable bus_vtable =
388 NULL, /* handle_get_property, */
389 NULL /* handle_set_property */
392 static const GDBusInterfaceVTable status_vtable =
394 NULL, /* handle_method_call */
400 on_bus_acquired (GDBusConnection *connection,
404 A11yBusLauncher *app = user_data;
406 guint registration_id;
408 if (connection == NULL)
410 g_main_loop_quit (app->loop);
413 app->session_bus = connection;
415 if (app->launch_immediately)
417 ensure_a11y_bus (app);
418 if (app->state == A11Y_BUS_STATE_ERROR)
420 g_main_loop_quit (app->loop);
426 registration_id = g_dbus_connection_register_object (connection,
428 introspection_data->interfaces[0],
433 if (registration_id == 0)
435 g_error ("%s", error->message);
436 g_clear_error (&error);
439 g_dbus_connection_register_object (connection,
441 introspection_data->interfaces[1],
449 on_name_lost (GDBusConnection *connection,
453 A11yBusLauncher *app = user_data;
454 if (app->session_bus == NULL
455 && connection == NULL
456 && app->a11y_launch_error_message == NULL)
457 app->a11y_launch_error_message = g_strdup ("Failed to connect to session bus");
458 g_main_loop_quit (app->loop);
462 on_name_acquired (GDBusConnection *connection,
466 A11yBusLauncher *app = user_data;
470 static int sigterm_pipefd[2];
473 sigterm_handler (int signum)
475 write (sigterm_pipefd[1], "X", 1);
479 on_sigterm_pipe (GIOChannel *channel,
480 GIOCondition condition,
483 A11yBusLauncher *app = data;
485 g_main_loop_quit (app->loop);
491 init_sigterm_handling (A11yBusLauncher *app)
493 GIOChannel *sigterm_channel;
495 if (pipe (sigterm_pipefd) < 0)
496 g_error ("Failed to create pipe: %s", strerror (errno));
497 signal (SIGTERM, sigterm_handler);
499 sigterm_channel = g_io_channel_unix_new (sigterm_pipefd[0]);
500 g_io_add_watch (sigterm_channel,
501 G_IO_IN | G_IO_ERR | G_IO_HUP,
512 Display *bridge_display;
514 unsigned char *data = NULL;
515 unsigned long nitems;
516 unsigned long leftover;
517 gboolean result = FALSE;
519 bridge_display = XOpenDisplay (NULL);
523 AT_SPI_BUS = XInternAtom (bridge_display, "AT_SPI_BUS", False);
524 XGetWindowProperty (bridge_display,
525 XDefaultRootWindow (bridge_display),
527 (long) BUFSIZ, False,
528 (Atom) 31, &actual_type, &actual_format,
529 &nitems, &leftover, &data);
533 GDBusConnection *bus;
534 bus = g_dbus_connection_new_for_address_sync ((const gchar *)data, 0,
539 g_object_unref (bus);
543 XCloseDisplay (bridge_display);
551 get_schema (const gchar *name)
553 const char * const *schemas = NULL;
556 schemas = g_settings_list_schemas ();
557 for (i = 0; schemas[i]; i++)
559 if (!strcmp (schemas[i], name))
560 return g_settings_new (schemas[i]);
567 gsettings_key_changed (GSettings *gsettings, const gchar *key, void *user_data)
569 gboolean new_val = g_settings_get_boolean (gsettings, key);
570 A11yBusLauncher *app = user_data;
572 if (!strcmp (key, "toolkit-accessibility"))
573 handle_a11y_enabled_change (_global_app, new_val, FALSE);
574 else if (!strcmp (key, "screen-reader-enabled"))
575 handle_screen_reader_enabled_change (_global_app, new_val, FALSE);
579 _launch_screen_reader(A11yBusLauncher *bl)
582 gboolean ret = FALSE;
584 kb = bundle_create();
588 appsvc_set_operation(kb, APP_CONTROL_OPERATION_SCREEN_READ);
590 bl->pid = appsvc_usr_run_service(kb, 0, NULL, NULL, getuid());
600 _terminate_screen_reader(A11yBusLauncher *bl)
606 LOGD("terminate process with pid %d", bl->pid);
607 if (!aul_terminate_pid(bl->pid))
613 LOGD("Unable to terminate process using aul api. Sending SIGTERM signal");
614 ret = kill(bl->pid, SIGTERM);
621 LOGD("Unable to terminate process: %d with api or signal.", bl->pid);
625 void screen_reader_cb(keynode_t *node, void *user_data)
627 A11yBusLauncher *bl = user_data;
630 ret = vconf_keynode_get_bool(node);
634 bl->screen_reader_needed = ret;
636 if (!bl->screen_reader_needed && (bl->pid > 0))
637 _terminate_screen_reader(bl);
638 else if (bl->screen_reader_needed && (bl->pid <= 0))
639 _launch_screen_reader(bl);
646 GError *error = NULL;
648 GDBusConnection *session_bus;
650 gboolean a11y_set = FALSE;
651 gboolean screen_reader_set = FALSE;
654 if (already_running ())
657 _global_app = g_slice_new0 (A11yBusLauncher);
658 _global_app->loop = g_main_loop_new (NULL, FALSE);
660 for (i = 1; i < argc; i++)
662 if (!strcmp (argv[i], "--launch-immediately"))
663 _global_app->launch_immediately = TRUE;
664 else if (sscanf (argv[i], "--a11y=%d", &_global_app->a11y_enabled) == 2)
666 else if (sscanf (argv[i], "--screen-reader=%d",
667 &_global_app->screen_reader_enabled) == 2)
668 screen_reader_set = TRUE;
670 g_error ("usage: %s [--launch-immediately] [--a11y=0|1] [--screen-reader=0|1]", argv[0]);
673 _global_app->interface_schema = get_schema ("org.gnome.desktop.interface");
674 _global_app->a11y_schema = get_schema ("org.gnome.desktop.a11y.applications");
678 _global_app->a11y_enabled = _global_app->interface_schema
679 ? g_settings_get_boolean (_global_app->interface_schema, "toolkit-accessibility")
680 : _global_app->launch_immediately;
683 if (!screen_reader_set)
685 _global_app->screen_reader_enabled = _global_app->a11y_schema
686 ? g_settings_get_boolean (_global_app->a11y_schema, "screen-reader-enabled")
690 if (_global_app->interface_schema)
691 g_signal_connect (_global_app->interface_schema,
692 "changed::toolkit-accessibility",
693 G_CALLBACK (gsettings_key_changed), _global_app);
695 if (_global_app->a11y_schema)
696 g_signal_connect (_global_app->a11y_schema,
697 "changed::screen-reader-enabled",
698 G_CALLBACK (gsettings_key_changed), _global_app);
700 init_sigterm_handling (_global_app);
702 introspection_data = g_dbus_node_info_new_for_xml (introspection_xml, NULL);
703 g_assert (introspection_data != NULL);
705 name_owner_id = g_bus_own_name (G_BUS_TYPE_SESSION,
707 G_BUS_NAME_OWNER_FLAGS_ALLOW_REPLACEMENT,
714 int ret = vconf_get_bool("db/menu/accessibility/screen_reader", &_global_app->screen_reader_needed);
717 LOGD("Could not read 'db/menu/accessibility/screen_reader' key value.\n");
720 ret = vconf_notify_key_changed("db/menu/accessibility/screen_reader", screen_reader_cb, _global_app);
723 LOGD("Could not add information level callback\n");
726 if (_global_app->screen_reader_needed)
727 _launch_screen_reader(_global_app);
729 g_main_loop_run (_global_app->loop);
731 if (_global_app->a11y_bus_pid > 0)
732 kill (_global_app->a11y_bus_pid, SIGTERM);
734 /* Clear the X property if our bus is gone; in the case where e.g.
735 * GDM is launching a login on an X server it was using before,
736 * we don't want early login processes to pick up the stale address.
740 Display *display = XOpenDisplay (NULL);
743 Atom bus_address_atom = XInternAtom (display, "AT_SPI_BUS", False);
744 XDeleteProperty (display,
745 XDefaultRootWindow (display),
749 XCloseDisplay (display);
754 if (_global_app->a11y_launch_error_message)
756 g_printerr ("Failed to launch bus: %s", _global_app->a11y_launch_error_message);