1 files changed, 112 insertions, 0 deletions
diff --git a/accessible/windows/msaa/Compatibility.cpp b/accessible/windows/msaa/Compatibility.cpp
new file mode 100644
index 0000000000..31026c586f
--- /dev/null
+++ b/accessible/windows/msaa/Compatibility.cpp
@@ -0,0 +1,112 @@
+/* -*- 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 "Compatibility.h"
+
+#include "nsWinUtils.h"
+#include "Statistics.h"
+
+#include "mozilla/Preferences.h"
+
+using namespace mozilla;
+using namespace mozilla::a11y;
+
+/**
+ * Return true if module version is lesser than the given version.
+ */
+bool
+IsModuleVersionLessThan(HMODULE aModuleHandle, DWORD aMajor, DWORD aMinor)
+{
+  wchar_t fileName[MAX_PATH];
+  ::GetModuleFileNameW(aModuleHandle, fileName, MAX_PATH);
+
+  DWORD dummy = 0;
+  DWORD length = ::GetFileVersionInfoSizeW(fileName, &dummy);
+
+  LPBYTE versionInfo = new BYTE[length];
+  ::GetFileVersionInfoW(fileName, 0, length, versionInfo);
+
+  UINT uLen;
+  VS_FIXEDFILEINFO* fixedFileInfo = nullptr;
+  ::VerQueryValueW(versionInfo, L"\\", (LPVOID*)&fixedFileInfo, &uLen);
+  DWORD dwFileVersionMS = fixedFileInfo->dwFileVersionMS;
+  DWORD dwFileVersionLS = fixedFileInfo->dwFileVersionLS;
+  delete [] versionInfo;
+
+  DWORD dwLeftMost = HIWORD(dwFileVersionMS);
+  DWORD dwSecondRight = HIWORD(dwFileVersionLS);
+  return (dwLeftMost < aMajor ||
+    (dwLeftMost == aMajor && dwSecondRight < aMinor));
+}
+
+
+////////////////////////////////////////////////////////////////////////////////
+// Compatibility
+////////////////////////////////////////////////////////////////////////////////
+
+uint32_t Compatibility::sConsumers = Compatibility::UNKNOWN;
+
+void
+Compatibility::Init()
+{
+  // Note we collect some AT statistics/telemetry here for convenience.
+
+  HMODULE jawsHandle = ::GetModuleHandleW(L"jhook");
+  if (jawsHandle)
+    sConsumers |= (IsModuleVersionLessThan(jawsHandle, 8, 2173)) ?
+                   OLDJAWS : JAWS;
+
+  if (::GetModuleHandleW(L"gwm32inc"))
+    sConsumers |= WE;
+
+  if (::GetModuleHandleW(L"dolwinhk"))
+    sConsumers |= DOLPHIN;
+
+  if (::GetModuleHandleW(L"STSA32"))
+    sConsumers |= SEROTEK;
+
+  if (::GetModuleHandleW(L"nvdaHelperRemote"))
+    sConsumers |= NVDA;
+
+  if (::GetModuleHandleW(L"OsmHooks"))
+    sConsumers |= COBRA;
+
+  if (::GetModuleHandleW(L"WebFinderRemote"))
+    sConsumers |= ZOOMTEXT;
+
+  if (::GetModuleHandleW(L"Kazahook"))
+    sConsumers |= KAZAGURU;
+
+  if (::GetModuleHandleW(L"TextExtractorImpl32") ||
+      ::GetModuleHandleW(L"TextExtractorImpl64"))
+    sConsumers |= YOUDAO;
+
+  if (::GetModuleHandleW(L"uiautomation") ||
+      ::GetModuleHandleW(L"uiautomationcore"))
+    sConsumers |= UIAUTOMATION;
+
+  // If we have a known consumer remove the unknown bit.
+  if (sConsumers != Compatibility::UNKNOWN)
+    sConsumers ^= Compatibility::UNKNOWN;
+
+  // Gather telemetry
+  uint32_t temp = sConsumers;
+  for (int i = 0; temp; i++) {
+    if (temp & 0x1)
+      statistics::A11yConsumers(i);
+
+    temp >>= 1;
+  }
+
+  // Turn off new tab switching for Jaws and WE.
+  if (sConsumers & (JAWS | OLDJAWS | WE)) {
+    // Check to see if the pref for disallowing CtrlTab is already set. If so,
+    // bail out (respect the user settings). If not, set it.
+    if (!Preferences::HasUserValue("browser.ctrlTab.disallowForScreenReaders"))
+      Preferences::SetBool("browser.ctrlTab.disallowForScreenReaders", true);
+  }
+}
+