From e0759926e6db62c9231018fb1a3c0420e20c5b94 Mon Sep 17 00:00:00 2001
From: Cameron McCormack <cam@mcc.id.au>
Date: Thu, 23 Jun 2011 08:48:24 +1200
Subject: [PATCH] Bug 640587 - Disable the swipe gesture half of the Elantech
 hack for driver versions < 8. r=jimm

---
 widget/src/windows/nsWindow.cpp | 35 +++++++++++++++++++--------------
 widget/src/windows/nsWindow.h   |  3 ++-
 2 files changed, 22 insertions(+), 16 deletions(-)

diff --git a/widget/src/windows/nsWindow.cpp b/widget/src/windows/nsWindow.cpp
index 5672373008f..3746be107aa 100644
--- a/widget/src/windows/nsWindow.cpp
+++ b/widget/src/windows/nsWindow.cpp
@@ -274,8 +274,10 @@ int             nsWindow::sTrimOnMinimize         = 2;
 PRBool          nsWindow::sDefaultTrackPointHack  = PR_FALSE;
 // Default value for general window class (used when the pref is the empty string).
 const char*     nsWindow::sDefaultMainWindowClass = kClassNameGeneral;
-// Whether to enable the Elantech gesture hack.
-PRBool          nsWindow::sUseElantechGestureHacks = PR_FALSE;
+// Whether to enable the Elantech swipe gesture hack.
+PRBool          nsWindow::sUseElantechSwipeHack  = PR_FALSE;
+// Whether to enable the Elantech pinch-to-zoom gesture hack.
+PRBool          nsWindow::sUseElantechPinchHack  = PR_FALSE;
 
 // If we're using D3D9, this will not be allowed during initial 5 seconds.
 bool            nsWindow::sAllowD3D9              = false;
@@ -6651,7 +6653,7 @@ LRESULT nsWindow::OnKeyDown(const MSG &aMsg,
     aMsg.wParam != VK_PROCESSKEY ? aMsg.wParam : ::ImmGetVirtualKey(mWnd);
   gKbdLayout.OnKeyDown(virtualKeyCode);
 
-  if (sUseElantechGestureHacks) {
+  if (sUseElantechSwipeHack) {
     PerformElantechSwipeGestureHack(virtualKeyCode, aModKeyState);
   }
 
@@ -6994,9 +6996,11 @@ LRESULT nsWindow::OnKeyUp(const MSG &aMsg,
 {
   UINT virtualKeyCode = aMsg.wParam;
 
-  if (sUseElantechGestureHacks) {
+  if (sUseElantechSwipeHack) {
     PerformElantechSwipeGestureHack(virtualKeyCode, aModKeyState);
+  }
 
+  if (sUseElantechPinchHack) {
     // Version 8 of the Elantech touchpad driver sends these messages for
     // zoom gestures:
     //
@@ -7609,7 +7613,7 @@ PRBool nsWindow::HandleScrollingPlugins(UINT aMsg, WPARAM aWParam,
   // is another app's window or no window under the
   // pointer.
 
-  if (sUseElantechGestureHacks && IsElantechHelperWindow(destWnd)) {
+  if (sUseElantechPinchHack && IsElantechHelperWindow(destWnd)) {
     // The Elantech driver places a window right underneath the cursor
     // when sending a WM_MOUSEWHEEL event to us as part of a pinch-to-zoom
     // gesture.  We detect that here, and search for our window that would
@@ -8883,8 +8887,8 @@ IsObsoleteSynapticsDriver()
   return majorVersion < 15;
 }
 
-static PRBool
-IsObsoleteElantechDriver()
+static PRInt32
+GetElantechDriverMajorVersion()
 {
   PRUnichar buf[40];
   // The driver version is found in one of these two registry keys.
@@ -8907,18 +8911,17 @@ IsObsoleteElantechDriver()
   // or at the start of the string.
   for (PRUnichar* p = buf; *p; p++) {
     if (*p >= L'0' && *p <= L'9' && (p == buf || *(p - 1) == L' ')) {
-      int majorVersion = wcstol(p, NULL, 10);
-      // Versions 7 and 8 need the hack.
-      if (majorVersion == 7 || majorVersion == 8)
-        return PR_TRUE;
+      return wcstol(p, NULL, 10);
     }
   }
 
-  return PR_FALSE;
+  return 0;
 }
 
 void nsWindow::InitInputWorkaroundPrefDefaults()
 {
+  PRUint32 elantechDriverVersion = GetElantechDriverMajorVersion();
+
   if (HasRegistryKey(HKEY_CURRENT_USER, L"Software\\Lenovo\\TrackPoint")) {
     sDefaultTrackPointHack = PR_TRUE;
   } else if (HasRegistryKey(HKEY_CURRENT_USER, L"Software\\Lenovo\\UltraNav")) {
@@ -8927,13 +8930,15 @@ void nsWindow::InitInputWorkaroundPrefDefaults()
     sDefaultTrackPointHack = PR_TRUE;
   } else if ((HasRegistryKey(HKEY_CURRENT_USER, L"Software\\Synaptics\\SynTPEnh\\UltraNavUSB") ||
               HasRegistryKey(HKEY_CURRENT_USER, L"Software\\Synaptics\\SynTPEnh\\UltraNavPS2")) &&
-              IsObsoleteSynapticsDriver()) {
+              elantechDriverVersion != 0 && elantechDriverVersion <= 8) {
     sDefaultTrackPointHack = PR_TRUE;
   }
 
-  sUseElantechGestureHacks =
+  PRBool useElantechGestureHacks =
     GetInputWorkaroundPref("ui.elantech_gesture_hacks.enabled",
-                           IsObsoleteElantechDriver());
+                           elantechDriverVersion != 0);
+  sUseElantechSwipeHack = useElantechGestureHacks && elantechDriverVersion <= 7;
+  sUseElantechPinchHack = useElantechGestureHacks && elantechDriverVersion <= 8;
 }
 
 LPARAM nsWindow::lParamToScreen(LPARAM lParam)
diff --git a/widget/src/windows/nsWindow.h b/widget/src/windows/nsWindow.h
index 3279ed2798f..3488cf3011c 100644
--- a/widget/src/windows/nsWindow.h
+++ b/widget/src/windows/nsWindow.h
@@ -526,7 +526,8 @@ protected:
   static int            sTrimOnMinimize;
   static PRBool         sDefaultTrackPointHack;
   static const char*    sDefaultMainWindowClass;
-  static PRBool         sUseElantechGestureHacks;
+  static PRBool         sUseElantechSwipeHack;
+  static PRBool         sUseElantechPinchHack;
   static bool           sAllowD3D9;
 
   // Always use the helper method to read this property.  See bug 603793.