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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
#include "Platform.h"
#include "nsIAccessibleEvent.h"
#include "nsIGSettingsService.h"
#include "nsMai.h"
#include "nsServiceManagerUtils.h"
#include "prenv.h"
#include "prlink.h"
#ifdef MOZ_ENABLE_DBUS
# include <dbus/dbus.h>
#endif
#include <gtk/gtk.h>
using namespace mozilla;
using namespace mozilla::a11y;
int atkMajorVersion = 1, atkMinorVersion = 12, atkMicroVersion = 0;
GType (*gAtkTableCellGetTypeFunc)();
extern "C" {
typedef GType (*AtkGetTypeType)(void);
typedef void (*AtkBridgeAdaptorInit)(int*, char**[]);
}
static PRLibrary* sATKLib = nullptr;
static const char sATKLibName[] = "libatk-1.0.so.0";
static const char sATKHyperlinkImplGetTypeSymbol[] =
"atk_hyperlink_impl_get_type";
gboolean toplevel_event_watcher(GSignalInvocationHint*, guint, const GValue*,
gpointer);
static bool sToplevel_event_hook_added = false;
static gulong sToplevel_show_hook = 0;
static gulong sToplevel_hide_hook = 0;
GType g_atk_hyperlink_impl_type = G_TYPE_INVALID;
struct AtkBridgeModule {
const char* libName;
PRLibrary* lib;
const char* initName;
AtkBridgeAdaptorInit init;
};
static AtkBridgeModule sAtkBridge = {"libatk-bridge-2.0.so.0", nullptr,
"atk_bridge_adaptor_init", nullptr};
static nsresult LoadGtkModule(AtkBridgeModule& aModule) {
NS_ENSURE_ARG(aModule.libName);
if (!(aModule.lib = PR_LoadLibrary(aModule.libName))) {
return NS_ERROR_FAILURE;
}
// we have loaded the library, try to get the function ptrs
if (!(aModule.init = (AtkBridgeAdaptorInit)PR_FindFunctionSymbol(
aModule.lib, aModule.initName))) {
// fail, :(
PR_UnloadLibrary(aModule.lib);
aModule.lib = nullptr;
return NS_ERROR_FAILURE;
}
return NS_OK;
}
void a11y::PlatformInit() {
if (!ShouldA11yBeEnabled()) return;
sATKLib = PR_LoadLibrary(sATKLibName);
if (!sATKLib) return;
AtkGetTypeType pfn_atk_hyperlink_impl_get_type =
(AtkGetTypeType)PR_FindFunctionSymbol(sATKLib,
sATKHyperlinkImplGetTypeSymbol);
if (pfn_atk_hyperlink_impl_get_type) {
g_atk_hyperlink_impl_type = pfn_atk_hyperlink_impl_get_type();
}
gAtkTableCellGetTypeFunc =
(GType(*)())PR_FindFunctionSymbol(sATKLib, "atk_table_cell_get_type");
const char* (*atkGetVersion)() =
(const char* (*)())PR_FindFunctionSymbol(sATKLib, "atk_get_version");
if (atkGetVersion) {
const char* version = atkGetVersion();
if (version) {
char* endPtr = nullptr;
atkMajorVersion = strtol(version, &endPtr, 10);
if (atkMajorVersion != 0L) {
atkMinorVersion = strtol(endPtr + 1, &endPtr, 10);
if (atkMinorVersion != 0L) {
atkMicroVersion = strtol(endPtr + 1, &endPtr, 10);
}
}
}
}
// Initialize the MAI Utility class, it will overwrite gail_util.
g_type_class_unref(g_type_class_ref(mai_util_get_type()));
// Init atk-bridge now
PR_SetEnv("NO_AT_BRIDGE=0");
nsresult rv = LoadGtkModule(sAtkBridge);
if (NS_SUCCEEDED(rv)) {
(*sAtkBridge.init)(nullptr, nullptr);
}
if (!sToplevel_event_hook_added) {
sToplevel_event_hook_added = true;
sToplevel_show_hook = g_signal_add_emission_hook(
g_signal_lookup("show", GTK_TYPE_WINDOW), 0, toplevel_event_watcher,
reinterpret_cast<gpointer>(nsIAccessibleEvent::EVENT_SHOW), nullptr);
sToplevel_hide_hook = g_signal_add_emission_hook(
g_signal_lookup("hide", GTK_TYPE_WINDOW), 0, toplevel_event_watcher,
reinterpret_cast<gpointer>(nsIAccessibleEvent::EVENT_HIDE), nullptr);
}
}
void a11y::PlatformShutdown() {
if (sToplevel_event_hook_added) {
sToplevel_event_hook_added = false;
g_signal_remove_emission_hook(g_signal_lookup("show", GTK_TYPE_WINDOW),
sToplevel_show_hook);
g_signal_remove_emission_hook(g_signal_lookup("hide", GTK_TYPE_WINDOW),
sToplevel_hide_hook);
}
if (sAtkBridge.lib) {
// Do not shutdown/unload atk-bridge,
// an exit function registered will take care of it
// PR_UnloadLibrary(sAtkBridge.lib);
sAtkBridge.lib = nullptr;
sAtkBridge.init = nullptr;
}
// if (sATKLib) {
// PR_UnloadLibrary(sATKLib);
// sATKLib = nullptr;
// }
}
static const char sAccEnv[] = "GNOME_ACCESSIBILITY";
#ifdef MOZ_ENABLE_DBUS
static DBusPendingCall* sPendingCall = nullptr;
#endif
void a11y::PreInit() {
#ifdef MOZ_ENABLE_DBUS
static bool sChecked = FALSE;
if (sChecked) return;
sChecked = TRUE;
// dbus is only checked if GNOME_ACCESSIBILITY is unset
// also make sure that a session bus address is available to prevent dbus from
// starting a new one. Dbus confuses the test harness when it creates a new
if (PR_GetEnv(sAccEnv) || !PR_GetEnv("DBUS_SESSION_BUS_ADDRESS")) return;
DBusConnection* bus = dbus_bus_get(DBUS_BUS_SESSION, nullptr);
if (!bus) return;
dbus_connection_set_exit_on_disconnect(bus, FALSE);
static const char* iface = "org.a11y.Status";
static const char* member = "IsEnabled";
DBusMessage* message;
message =
dbus_message_new_method_call("org.a11y.Bus", "/org/a11y/bus",
"org.freedesktop.DBus.Properties", "Get");
if (!message) goto dbus_done;
dbus_message_append_args(message, DBUS_TYPE_STRING, &iface, DBUS_TYPE_STRING,
&member, DBUS_TYPE_INVALID);
dbus_connection_send_with_reply(bus, message, &sPendingCall, 1000);
dbus_message_unref(message);
dbus_done:
dbus_connection_unref(bus);
#endif
}
bool a11y::ShouldA11yBeEnabled() {
static bool sChecked = false, sShouldEnable = false;
if (sChecked) return sShouldEnable;
sChecked = true;
EPlatformDisabledState disabledState = PlatformDisabledState();
if (disabledState == ePlatformIsDisabled) {
return sShouldEnable = false;
}
if (disabledState == ePlatformIsForceEnabled) {
return sShouldEnable = true;
}
// check if accessibility enabled/disabled by environment variable
const char* envValue = PR_GetEnv(sAccEnv);
if (envValue) return sShouldEnable = !!atoi(envValue);
#ifdef MOZ_ENABLE_DBUS
PreInit();
bool dbusSuccess = false;
DBusMessage* reply = nullptr;
if (!sPendingCall) goto dbus_done;
dbus_pending_call_block(sPendingCall);
reply = dbus_pending_call_steal_reply(sPendingCall);
dbus_pending_call_unref(sPendingCall);
sPendingCall = nullptr;
if (!reply ||
dbus_message_get_type(reply) != DBUS_MESSAGE_TYPE_METHOD_RETURN ||
strcmp(dbus_message_get_signature(reply), DBUS_TYPE_VARIANT_AS_STRING)) {
goto dbus_done;
}
DBusMessageIter iter, iter_variant, iter_struct;
dbus_bool_t dResult;
dbus_message_iter_init(reply, &iter);
dbus_message_iter_recurse(&iter, &iter_variant);
switch (dbus_message_iter_get_arg_type(&iter_variant)) {
case DBUS_TYPE_STRUCT:
// at-spi2-core 2.2.0-2.2.1 had a bug where it returned a struct
dbus_message_iter_recurse(&iter_variant, &iter_struct);
if (dbus_message_iter_get_arg_type(&iter_struct) == DBUS_TYPE_BOOLEAN) {
dbus_message_iter_get_basic(&iter_struct, &dResult);
sShouldEnable = dResult;
dbusSuccess = true;
}
break;
case DBUS_TYPE_BOOLEAN:
dbus_message_iter_get_basic(&iter_variant, &dResult);
sShouldEnable = dResult;
dbusSuccess = true;
break;
default:
break;
}
dbus_done:
if (reply) dbus_message_unref(reply);
if (dbusSuccess) return sShouldEnable;
#endif
// check GSettings
#define GSETINGS_A11Y_INTERFACE "org.gnome.desktop.interface"
#define GSETINGS_A11Y_KEY "toolkit-accessibility"
nsCOMPtr<nsIGSettingsService> gsettings =
do_GetService(NS_GSETTINGSSERVICE_CONTRACTID);
nsCOMPtr<nsIGSettingsCollection> a11y_settings;
if (gsettings) {
gsettings->GetCollectionForSchema(nsLiteralCString(GSETINGS_A11Y_INTERFACE),
getter_AddRefs(a11y_settings));
if (a11y_settings) {
a11y_settings->GetBoolean(nsLiteralCString(GSETINGS_A11Y_KEY),
&sShouldEnable);
}
}
return sShouldEnable;
}