The Tor Browser: accessible/src/atk/Platform.cpp@97036ab72558 (annotated)

accessible/src/atk/Platform.cpp@97036ab72558 (annotated)

accessible/src/atk/Platform.cpp

Tue, 06 Jan 2015 21:39:09 +0100

author: Michael Schloh von Bennewitz <michael@schloh.com>
date: Tue, 06 Jan 2015 21:39:09 +0100
branch: TOR_BUG_9701
changeset 8: 97036ab72558
permissions: -rw-r--r--

Conditionally force memory storage according to privacy.thirdparty.isolate;
This solves Tor bug #9701, complying with disk avoidance documented in
https://www.torproject.org/projects/torbrowser/design/#disk-avoidance.

 /* -*- 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>
 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
 };
 static GnomeAccessibilityModule sGail = {
     "libgail.so", nullptr,
     "gnome_accessibility_module_init", nullptr,
     "gnome_accessibility_module_shutdown", nullptr
 };
 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.Append(":/usr/lib64:/usr/lib");
 #else
         libPath.Append(":/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));
             sub.Append("/gtk-2.0/modules/");
             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);
     }
   }
   // Load and initialize gail library.
   nsresult rv = LoadGtkModule(sGail);
   if (NS_SUCCEEDED(rv))
     (*sGail.init)();
   // 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");
   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),
 , 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 (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;
     }
     // 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
 static const char sGconfAccessibilityKey[] =
     "/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(sGconfAccessibilityKey), &sShouldEnable);
   return sShouldEnable;
 }

The Tor Browser / annotate

accessible/src/atk/Platform.cpp@97036ab72558 (annotated)

accessible/src/atk/Platform.cpp