From 0e3e95794fc5a250ab783925fa4d75bfb1aef0cd Mon Sep 17 00:00:00 2001
From: Magnus Olsen <magnus@greatlord.com>
Date: Sun, 21 May 2006 09:21:38 +0000
Subject: [PATCH] patch from w3seek : optimize FindWindowEx and fix passing a
 NULL window class

svn path=/trunk/; revision=21960
---
 reactos/dll/win32/user32/windows/window.c     | 78 +++++++++------
 .../subsystems/win32/win32k/ntuser/window.c   | 95 ++++++++++---------
 2 files changed, 100 insertions(+), 73 deletions(-)

diff --git a/reactos/dll/win32/user32/windows/window.c b/reactos/dll/win32/user32/windows/window.c
index 26ad8bc8466..dfee0db790b 100644
--- a/reactos/dll/win32/user32/windows/window.c
+++ b/reactos/dll/win32/user32/windows/window.c
@@ -516,33 +516,51 @@ FindWindowExA(HWND hwndParent,
 	      LPCSTR lpszClass,
 	      LPCSTR lpszWindow)
 {
-   UNICODE_STRING ucClassName;
-   UNICODE_STRING ucWindowName;
+   UNICODE_STRING ucClassName, *pucClassName = NULL;
+   UNICODE_STRING ucWindowName, *pucWindowName = NULL;
    HWND Result;
 
-   if (lpszClass == NULL)
-   {
-      ucClassName.Buffer = NULL;
-      ucClassName.Length = 0;
-   }
-   else if (IS_ATOM(lpszClass))
+   if (IS_ATOM(lpszClass))
    {
       ucClassName.Buffer = (LPWSTR)lpszClass;
       ucClassName.Length = 0;
+      pucClassName = &ucClassName;
    }
-   else
+   else if (lpszClass != NULL)
    {
-      RtlCreateUnicodeStringFromAsciiz(&ucClassName, (LPSTR)lpszClass);
+      if (!RtlCreateUnicodeStringFromAsciiz(&ucClassName,
+                                            (LPSTR)lpszClass))
+      {
+         SetLastError(ERROR_NOT_ENOUGH_MEMORY);
+         return NULL;
+      }
+      pucClassName = &ucClassName;
    }
 
-   RtlCreateUnicodeStringFromAsciiz(&ucWindowName, (LPSTR)lpszWindow);
+   if (lpszWindow != NULL)
+   {
+      if (!RtlCreateUnicodeStringFromAsciiz(&ucWindowName,
+                                            (LPSTR)lpszWindow))
+      {
+         if (!IS_ATOM(lpszClass) && lpszClass != NULL)
+            RtlFreeUnicodeString(&ucWindowName);
 
-   Result = NtUserFindWindowEx(hwndParent, hwndChildAfter, &ucClassName,
-      &ucWindowName);
+         SetLastError(ERROR_NOT_ENOUGH_MEMORY);
+         return NULL;
+      }
 
-   if (!IS_ATOM(lpszClass))
+      pucWindowName = &ucWindowName;
+   }
+
+   Result = NtUserFindWindowEx(hwndParent,
+                               hwndChildAfter,
+                               pucClassName,
+                               pucWindowName);
+
+   if (!IS_ATOM(lpszClass) && lpszClass != NULL)
       RtlFreeUnicodeString(&ucClassName);
-   RtlFreeUnicodeString(&ucWindowName);
+   if (lpszWindow != NULL)
+      RtlFreeUnicodeString(&ucWindowName);
 
    return Result;
 }
@@ -557,27 +575,33 @@ FindWindowExW(HWND hwndParent,
 	      LPCWSTR lpszClass,
 	      LPCWSTR lpszWindow)
 {
-   UNICODE_STRING ucClassName;
-   UNICODE_STRING ucWindowName;
+   UNICODE_STRING ucClassName, *pucClassName = NULL;
+   UNICODE_STRING ucWindowName, *pucWindowName = NULL;
 
-   if (lpszClass == NULL)
+   if (IS_ATOM(lpszClass))
    {
-      ucClassName.Buffer = NULL;
       ucClassName.Length = 0;
-   }
-   else if (IS_ATOM(lpszClass))
-   {
-      RtlInitUnicodeString(&ucClassName, NULL);
       ucClassName.Buffer = (LPWSTR)lpszClass;
+      pucClassName = &ucClassName;
    }
-   else
+   else if (lpszClass != NULL)
    {
-      RtlInitUnicodeString(&ucClassName, lpszClass);
+      RtlInitUnicodeString(&ucClassName,
+                           lpszClass);
+      pucClassName = &ucClassName;
    }
 
-   RtlInitUnicodeString(&ucWindowName, lpszWindow);
+   if (lpszWindow != NULL)
+   {
+      RtlInitUnicodeString(&ucWindowName,
+                           lpszWindow);
+      pucWindowName = &ucWindowName;
+   }
 
-   return NtUserFindWindowEx(hwndParent, hwndChildAfter, &ucClassName, &ucWindowName);
+   return NtUserFindWindowEx(hwndParent,
+                             hwndChildAfter,
+                             pucClassName,
+                             pucWindowName);
 }
 
 
diff --git a/reactos/subsystems/win32/win32k/ntuser/window.c b/reactos/subsystems/win32/win32k/ntuser/window.c
index a0b375e909d..b35d07d5f2d 100644
--- a/reactos/subsystems/win32/win32k/ntuser/window.c
+++ b/reactos/subsystems/win32/win32k/ntuser/window.c
@@ -2433,61 +2433,64 @@ NtUserFindWindowEx(HWND hwndParent,
    DPRINT("Enter NtUserFindWindowEx\n");
    UserEnterShared();
 
-   _SEH_TRY
+   if (ucClassName != NULL || ucWindowName != NULL)
    {
+       _SEH_TRY
+       {
+           if (ucClassName != NULL)
+           {
+               ClassName = ProbeForReadUnicodeString(ucClassName);
+               if (ClassName.Length != 0)
+               {
+                   ProbeForRead(ClassName.Buffer,
+                                ClassName.Length,
+                                sizeof(WCHAR));
+               }
+               else if (!IS_ATOM(ClassName.Buffer))
+               {
+                   SetLastWin32Error(ERROR_INVALID_PARAMETER);
+                   _SEH_LEAVE;
+               }
+
+               if (!IntGetAtomFromStringOrAtom(&ClassName,
+                                               &ClassAtom))
+               {
+                   _SEH_LEAVE;
+               }
+           }
+
+           if (ucWindowName != NULL)
+           {
+               WindowName = ProbeForReadUnicodeString(ucWindowName);
+               if (WindowName.Length != 0)
+               {
+                   ProbeForRead(WindowName.Buffer,
+                                WindowName.Length,
+                                sizeof(WCHAR));
+               }
+           }
+       }
+       _SEH_HANDLE
+       {
+           SetLastNtError(_SEH_GetExceptionCode());
+           RETURN(NULL);
+       }
+       _SEH_END;
+
        if (ucClassName != NULL)
        {
-           ClassName = ProbeForReadUnicodeString(ucClassName);
-           if (ClassName.Length != 0)
-           {
-               ProbeForRead(ClassName.Buffer,
-                            ClassName.Length,
-                            sizeof(WCHAR));
-           }
-           else if (ClassName.Buffer != NULL && !IS_ATOM(ClassName.Buffer))
+           if (ClassName.Length == 0 && ClassName.Buffer != NULL &&
+               !IS_ATOM(ClassName.Buffer))
            {
                SetLastWin32Error(ERROR_INVALID_PARAMETER);
-               _SEH_LEAVE;
+               RETURN(NULL);
            }
-
-           if (!IntGetAtomFromStringOrAtom(&ClassName,
-                                           &ClassAtom))
+           else if (ClassAtom == (RTL_ATOM)0)
            {
-               _SEH_LEAVE;
+               /* LastError code was set by IntGetAtomFromStringOrAtom */
+               RETURN(NULL);
            }
        }
-
-       if (ucWindowName != NULL)
-       {
-           WindowName = ProbeForReadUnicodeString(ucWindowName);
-           if (WindowName.Length != 0)
-           {
-               ProbeForRead(WindowName.Buffer,
-                            WindowName.Length,
-                            sizeof(WCHAR));
-           }
-       }
-   }
-   _SEH_HANDLE
-   {
-       SetLastNtError(_SEH_GetExceptionCode());
-       RETURN(NULL);
-   }
-   _SEH_END;
-
-   if (ucClassName != NULL)
-   {
-       if (ClassName.Length == 0 && ClassName.Buffer != NULL &&
-           !IS_ATOM(ClassName.Buffer))
-       {
-           SetLastWin32Error(ERROR_INVALID_PARAMETER);
-           RETURN(NULL);
-       }
-       else if (ClassAtom == (RTL_ATOM)0)
-       {
-           /* LastError code was set by IntGetAtomFromStringOrAtom */
-           RETURN(NULL);
-       }
    }
 
    Desktop = IntGetCurrentThreadDesktopWindow();