DXR is a code search and navigation tool aimed at making sense of large projects. It supports full-text and regex searches as well as structural queries.

Mercurial (dcc6d7a0dc00)

VCS Links

Line Code
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372
/* -*- 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;
}