gecko-dev/accessible/atk/Platform.cpp

373 lines
11 KiB
C++

/* -*- 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
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#include "Platform.h"
#include "nsIAccessibleEvent.h"
#include "nsIGConfService.h"
#include "nsIServiceManager.h"
#include "nsMai.h"
#include "AtkSocketAccessible.h"
#include "prenv.h"
#include "prlink.h"
#ifdef MOZ_ENABLE_DBUS
#include <dbus/dbus.h>
#endif
#include <gtk/gtk.h>
#if (MOZ_WIDGET_GTK == 3)
extern "C" __attribute__((weak,visibility("default"))) int atk_bridge_adaptor_init(int*, char **[]);
#endif
using namespace mozilla;
using namespace mozilla::a11y;
int atkMajorVersion = 1, atkMinorVersion = 12;
extern "C" {
typedef GType (* AtkGetTypeType) (void);
typedef void (*GnomeAccessibilityInit) (void);
typedef void (*GnomeAccessibilityShutdown) (void);
}
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 GnomeAccessibilityModule
{
const char *libName;
PRLibrary *lib;
const char *initName;
GnomeAccessibilityInit init;
const char *shutdownName;
GnomeAccessibilityShutdown shutdown;
};
static GnomeAccessibilityModule sAtkBridge = {
#ifdef AIX
"libatk-bridge.a(libatk-bridge.so.0)", nullptr,
#else
"libatk-bridge.so", nullptr,
#endif
"gnome_accessibility_module_init", nullptr,
"gnome_accessibility_module_shutdown", nullptr
};
#if (MOZ_WIDGET_GTK == 2)
static GnomeAccessibilityModule sGail = {
"libgail.so", nullptr,
"gnome_accessibility_module_init", nullptr,
"gnome_accessibility_module_shutdown", nullptr
};
#endif
static nsresult
LoadGtkModule(GnomeAccessibilityModule& aModule)
{
NS_ENSURE_ARG(aModule.libName);
if (!(aModule.lib = PR_LoadLibrary(aModule.libName))) {
//try to load the module with "gtk-2.0/modules" appended
char *curLibPath = PR_GetLibraryPath();
nsAutoCString libPath(curLibPath);
#if defined(LINUX) && defined(__x86_64__)
libPath.AppendLiteral(":/usr/lib64:/usr/lib");
#else
libPath.AppendLiteral(":/usr/lib");
#endif
PR_FreeLibraryName(curLibPath);
int16_t loc1 = 0, loc2 = 0;
int16_t subLen = 0;
while (loc2 >= 0) {
loc2 = libPath.FindChar(':', loc1);
if (loc2 < 0)
subLen = libPath.Length() - loc1;
else
subLen = loc2 - loc1;
nsAutoCString sub(Substring(libPath, loc1, subLen));
#if (MOZ_WIDGET_GTK == 2)
sub.AppendLiteral("/gtk-2.0/modules/");
#else
sub.AppendLiteral("/gtk-3.0/modules/");
#endif
sub.Append(aModule.libName);
aModule.lib = PR_LoadLibrary(sub.get());
if (aModule.lib)
break;
loc1 = loc2+1;
}
if (!aModule.lib)
return NS_ERROR_FAILURE;
}
//we have loaded the library, try to get the function ptrs
if (!(aModule.init = PR_FindFunctionSymbol(aModule.lib,
aModule.initName)) ||
!(aModule.shutdown = PR_FindFunctionSymbol(aModule.lib,
aModule.shutdownName))) {
//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();
AtkGetTypeType pfn_atk_socket_get_type = (AtkGetTypeType)
PR_FindFunctionSymbol(sATKLib, AtkSocketAccessible::sATKSocketGetTypeSymbol);
if (pfn_atk_socket_get_type) {
AtkSocketAccessible::g_atk_socket_type = pfn_atk_socket_get_type();
AtkSocketAccessible::g_atk_socket_embed = (AtkSocketEmbedType)
PR_FindFunctionSymbol(sATKLib, AtkSocketAccessible ::sATKSocketEmbedSymbol);
AtkSocketAccessible::gCanEmbed =
AtkSocketAccessible::g_atk_socket_type != G_TYPE_INVALID &&
AtkSocketAccessible::g_atk_socket_embed;
}
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 (*endPtr == '.')
atkMinorVersion = strtol(endPtr + 1, &endPtr, 10);
}
}
#if (MOZ_WIDGET_GTK == 2)
// Load and initialize gail library.
nsresult rv = LoadGtkModule(sGail);
if (NS_SUCCEEDED(rv))
(*sGail.init)();
#endif
// 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");
#if (MOZ_WIDGET_GTK == 3)
if (atk_bridge_adaptor_init) {
atk_bridge_adaptor_init(nullptr, nullptr);
} else
#endif
{
nsresult rv = LoadGtkModule(sAtkBridge);
if (NS_SUCCEEDED(rv)) {
(*sAtkBridge.init)();
}
}
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
// if (sAtkBridge.shutdown)
// (*sAtkBridge.shutdown)();
// PR_UnloadLibrary(sAtkBridge.lib);
sAtkBridge.lib = nullptr;
sAtkBridge.init = nullptr;
sAtkBridge.shutdown = nullptr;
}
#if (MOZ_WIDGET_GTK == 2)
if (sGail.lib) {
// Do not shutdown gail because
// 1) Maybe it's not init-ed by us. e.g. GtkEmbed
// 2) We need it to avoid assert in spi_atk_tidy_windows
// if (sGail.shutdown)
// (*sGail.shutdown)();
// PR_UnloadLibrary(sGail.lib);
sGail.lib = nullptr;
sGail.init = nullptr;
sGail.shutdown = nullptr;
}
#endif
// 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
// process (see bug 693343)
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;
// 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 gconf-2 setting
#define GCONF_A11Y_KEY "/desktop/gnome/interface/accessibility"
nsresult rv = NS_OK;
nsCOMPtr<nsIGConfService> gconf =
do_GetService(NS_GCONFSERVICE_CONTRACTID, &rv);
if (NS_SUCCEEDED(rv) && gconf)
gconf->GetBool(NS_LITERAL_CSTRING(GCONF_A11Y_KEY), &sShouldEnable);
return sShouldEnable;
}