From 0a205b8bd5da3eb2cb61f00c09120052e8e4601c Mon Sep 17 00:00:00 2001
From: Thomas Bluemel <thomas@reactsoft.com>
Date: Mon, 5 Apr 2004 20:46:15 +0000
Subject: [PATCH] made the DCE list thread-safe

svn path=/trunk/; revision=8978
---
 reactos/subsys/win32k/ntuser/windc.c | 52 +++++++++++++++++++++-------
 1 file changed, 40 insertions(+), 12 deletions(-)

diff --git a/reactos/subsys/win32k/ntuser/windc.c b/reactos/subsys/win32k/ntuser/windc.c
index 2aaf0bd586b..8aa9f5fbb6a 100644
--- a/reactos/subsys/win32k/ntuser/windc.c
+++ b/reactos/subsys/win32k/ntuser/windc.c
@@ -16,7 +16,7 @@
  *  along with this program; if not, write to the Free Software
  *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
-/* $Id: windc.c,v 1.61 2004/03/23 18:08:07 weiden Exp $
+/* $Id: windc.c,v 1.62 2004/04/05 20:46:15 weiden Exp $
  *
  * COPYRIGHT:        See COPYING in the top level directory
  * PROJECT:          ReactOS kernel
@@ -49,14 +49,26 @@
 
 /* GLOBALS *******************************************************************/
 
+/* NOTE - I think we should store this per window station (including gdi objects) */
+
+static FAST_MUTEX DceListLock;
 static PDCE FirstDce = NULL;
 static HDC defaultDCstate;
 
+#define DCE_LockList ExAcquireFastMutex(&DceListLock)
+#define DCE_UnlockList ExReleaseFastMutex(&DceListLock)
+
 #define DCX_CACHECOMPAREMASK (DCX_CLIPSIBLINGS | DCX_CLIPCHILDREN | \
                               DCX_CACHE | DCX_WINDOW | DCX_PARENTCLIP)
 
 /* FUNCTIONS *****************************************************************/
 
+VOID FASTCALL
+DceInit(VOID)
+{
+  ExInitializeFastMutex(&DceListLock);
+}
+
 HRGN STDCALL
 DceGetVisRgn(HWND hWnd, ULONG Flags, HWND hWndChild, ULONG CFlags)
 {
@@ -111,8 +123,10 @@ DceAllocDCE(HWND hWnd, DCE_TYPE Type)
     }
   Dce->hwndCurrent = hWnd;
   Dce->hClipRgn = NULL;
+  DCE_LockList;
   Dce->next = FirstDce;
   FirstDce = Dce;
+  DCE_UnlockList;
 
   if (Type != DCE_CACHE_DC)
     {
@@ -408,6 +422,8 @@ NtUserGetDCEx(HWND hWnd, HANDLE ClipRegion, ULONG Flags)
     {
       DCE* DceEmpty = NULL;
       DCE* DceUnused = NULL;
+      
+      DCE_LockList;
 
       for (Dce = FirstDce; Dce != NULL; Dce = Dce->next)
 	{
@@ -430,6 +446,8 @@ NtUserGetDCEx(HWND hWnd, HANDLE ClipRegion, ULONG Flags)
 	    }
 	}
 
+      DCE_UnlockList;
+      
       if (Dce == NULL)
 	{
 	  Dce = (DceEmpty == NULL) ? DceEmpty : DceUnused;
@@ -555,7 +573,9 @@ BOOL FASTCALL
 DCE_InternalDelete(PDCE Dce)
 {
   PDCE PrevInList;
-
+  
+  DCE_LockList;
+  
   if (Dce == FirstDce)
     {
       FirstDce = Dce->next;
@@ -574,6 +594,8 @@ DCE_InternalDelete(PDCE Dce)
       assert(NULL != PrevInList);
     }
 
+  DCE_UnlockList;
+  
   return NULL != PrevInList;
 }
 
@@ -581,13 +603,17 @@ HWND FASTCALL
 IntWindowFromDC(HDC hDc)
 {
   DCE *Dce;
+  
+  DCE_LockList;
   for (Dce = FirstDce; Dce != NULL; Dce = Dce->next)
   {
     if(Dce->hDC == hDc)
     {
+      DCE_UnlockList;
       return Dce->hwndCurrent;
     }
   }
+  DCE_UnlockList;
   return 0;
 }
 
@@ -597,7 +623,8 @@ NtUserReleaseDC(HWND hWnd, HDC hDc)
   DCE *dce;
   INT nRet = 0;
 
-  /* FIXME USER_Lock(); */
+  DCE_LockList;
+  
   dce = FirstDce;
 
   DPRINT("%p %p\n", hWnd, hDc);
@@ -612,7 +639,7 @@ NtUserReleaseDC(HWND hWnd, HDC hDc)
       nRet = DceReleaseDC(dce);
     }
 
-  /* FIXME USER_Unlock(); */
+  DCE_UnlockList;
 
   return nRet;
 }
@@ -631,16 +658,8 @@ DceFreeDCE(PDCE dce)
       return NULL;
     }
 
-#if 0  /* FIXME */
-  USER_Lock();
-#endif
-
   ret = dce->next;
 
-#if 0 /* FIXME */
-  USER_Unlock();
-#endif
-
 #if 0 /* FIXME */
   SetDCHook(dce->hDC, NULL, 0L);
 #endif
@@ -668,6 +687,8 @@ DceFreeWindowDCE(PWINDOW_OBJECT Window)
 {
   DCE *pDCE;
 
+  DCE_LockList;
+  
   pDCE = FirstDce;
   while (pDCE)
     {
@@ -709,15 +730,18 @@ DceFreeWindowDCE(PWINDOW_OBJECT Window)
         }
       pDCE = pDCE->next;
     }
+    DCE_UnlockList;
 }
 
 void FASTCALL
 DceEmptyCache()
 {
+  DCE_LockList;
   while (FirstDce != NULL)
     {
       DceFreeDCE(FirstDce);
     }
+  DCE_UnlockList;
 }
 
 VOID FASTCALL 
@@ -732,6 +756,8 @@ DceResetActiveDCEs(PWINDOW_OBJECT Window, int DeltaX, int DeltaY)
       return;
     }
 
+  DCE_LockList;
+  
   pDCE = FirstDce;
   while (pDCE)
     {
@@ -785,6 +811,8 @@ DceResetActiveDCEs(PWINDOW_OBJECT Window, int DeltaX, int DeltaY)
         }
       pDCE = pDCE->next;
     }
+  
+  DCE_UnlockList;
 }
 
 /* EOF */