[tkreuzer] 29123: - make gdi object's type field more windows compatible, using only the basetype in the upper 16 bits - On windows deleted objects have a KernelData value != NULL, so don't check for that when validating a handle, instead check if the type field in the upper 16 bits is 0

Author: tkreuzer
Date: Thu Sep 20 20:13:55 2007
New Revision: 29123

URL: http://svn.reactos.org/svn/reactos?rev=29123&view=rev
Log:
- make gdi object's type field more windows compatible, using only the basetype in the upper 16 bits
- On windows deleted objects have a KernelData value != NULL, so don't check for that when validating a handle, instead check if the type field in the upper 16 bits is 0

Modified:
    trunk/reactos/dll/win32/gdi32/misc/misc.c
    trunk/reactos/include/reactos/win32k/ntgdihdl.h
    trunk/reactos/subsystems/win32/win32k/objects/gdiobj.c

Modified: trunk/reactos/dll/win32/gdi32/misc/misc.c
URL: http://svn.reactos.org/svn/reactos/trunk/reactos/dll/win32/gdi32/misc/misc.c...
==============================================================================
--- trunk/reactos/dll/win32/gdi32/misc/misc.c (original)
+++ trunk/reactos/dll/win32/gdi32/misc/misc.c Thu Sep 20 20:13:55 2007
@@ -94,9 +94,8 @@
 BOOL GdiIsHandleValid(HGDIOBJ hGdiObj)
 {
   PGDI_TABLE_ENTRY Entry = GdiHandleTable + GDI_HANDLE_GET_INDEX(hGdiObj);
-  if(Entry->KernelData != NULL && 
-                        (Entry->Type & GDI_HANDLE_TYPE_MASK) == 
-                                       (LONG)GDI_HANDLE_GET_TYPE(hGdiObj))
+  if((Entry->Type & GDI_ENTRY_BASETYPE_MASK) != 0 && 
+     (Entry->Type << GDI_ENTRY_UPPER_SHIFT) == GDI_HANDLE_GET_UPPER(hGdiObj))
   {
     HANDLE pid = (HANDLE)((ULONG_PTR)Entry->ProcessId & ~0x1);
     if(pid == NULL || pid == CurrentProcessId)
@@ -110,9 +109,8 @@
 BOOL GdiGetHandleUserData(HGDIOBJ hGdiObj, PVOID *UserData)
 {
   PGDI_TABLE_ENTRY Entry = GdiHandleTable + GDI_HANDLE_GET_INDEX(hGdiObj);
-  if(Entry->KernelData != NULL && 
-                        (Entry->Type & GDI_HANDLE_TYPE_MASK) == 
-                                       (LONG)GDI_HANDLE_GET_TYPE(hGdiObj))
+  if((Entry->Type & GDI_ENTRY_BASETYPE_MASK) != 0 && 
+     (Entry->Type << GDI_ENTRY_UPPER_SHIFT) == GDI_HANDLE_GET_UPPER(hGdiObj))
   {
     HANDLE pid = (HANDLE)((ULONG_PTR)Entry->ProcessId & ~0x1);
     if(pid == NULL || pid == CurrentProcessId)

Modified: trunk/reactos/include/reactos/win32k/ntgdihdl.h
URL: http://svn.reactos.org/svn/reactos/trunk/reactos/include/reactos/win32k/ntgd...
==============================================================================
--- trunk/reactos/include/reactos/win32k/ntgdihdl.h (original)
+++ trunk/reactos/include/reactos/win32k/ntgdihdl.h Thu Sep 20 20:13:55 2007
@@ -33,6 +33,7 @@
 #define GDI_ENTRY_STOCK_MASK 0x00000080
 #define GDI_ENTRY_REUSE_MASK 0x0000ff00
 #define GDI_ENTRY_REUSE_INC 0x00000100
+#define GDI_ENTRY_BASETYPE_MASK 0x001f0000
 #define GDI_ENTRY_REUSECNT_SHIFT 8
 #define GDI_ENTRY_UPPER_SHIFT 16

Modified: trunk/reactos/subsystems/win32/win32k/objects/gdiobj.c
URL: http://svn.reactos.org/svn/reactos/trunk/reactos/subsystems/win32/win32k/obj...
==============================================================================
--- trunk/reactos/subsystems/win32/win32k/objects/gdiobj.c (original)
+++ trunk/reactos/subsystems/win32/win32k/objects/gdiobj.c Thu Sep 20 20:13:55 2007
@@ -316,10 +316,10 @@
         DPRINT1("%s: Attempted to lock object 0x%x, wrong reuse counter (Handle: 0x%x, Entry: 0x%x)\n",
                 Function, hObj, GDI_HANDLE_GET_REUSECNT(hObj), GDI_ENTRY_GET_REUSECNT(Entry->Type));
     }
-    else if (GDI_HANDLE_GET_TYPE(hObj) != GDI_HANDLE_GET_TYPE(Entry->Type))
+    else if (GDI_HANDLE_GET_TYPE(hObj) != ((Entry->Type << GDI_ENTRY_UPPER_SHIFT) & GDI_HANDLE_TYPE_MASK))
     {
         DPRINT1("%s: Attempted to lock object 0x%x, type mismatch (Handle: 0x%x, Entry: 0x%x)\n",
-                Function, hObj, GDI_HANDLE_GET_TYPE(hObj), GDI_HANDLE_GET_TYPE(Entry->Type));
+                Function, hObj, GDI_HANDLE_GET_TYPE(hObj), (Entry->Type << GDI_ENTRY_UPPER_SHIFT) & GDI_HANDLE_TYPE_MASK);
     }
     else
     {
@@ -403,10 +403,10 @@

RtlZeroMemory(ObjectBody, GetObjectSize(TypeIndex));

-      /* FIXME: On Windows the higher 16 bit of the type field don't always match
-         the type from the handle, it is probably a storage type 
-         (type = pen, storage = brush) */
-    TypeInfo = (ObjectType & GDI_HANDLE_TYPE_MASK) | (ObjectType >> GDI_ENTRY_UPPER_SHIFT);
+    /* On Windows the higher 16 bit of the type field don't contain the
+       full type from the handle, but the base type.
+       (type = BRSUH, PEN, EXTPEN, basetype = BRUSH) */
+    TypeInfo = (ObjectType & GDI_HANDLE_BASETYPE_MASK) | (ObjectType >> GDI_ENTRY_UPPER_SHIFT);

FreeEntry = InterlockedPopEntrySList(&HandleTable->FreeEntriesHead);
     if(FreeEntry != NULL)
@@ -705,7 +705,7 @@
         Entry++, Index++)
     {
       /* ignore the lock bit */
-      if((HANDLE)((ULONG_PTR)Entry->ProcessId & ~0x1) == ProcId && (Entry->Type & ~GDI_HANDLE_REUSE_MASK) != 0)
+      if((HANDLE)((ULONG_PTR)Entry->ProcessId & ~0x1) == ProcId && (Entry->Type & ~GDI_ENTRY_REUSE_MASK) != 0)
       {
         HGDIOBJ ObjectHandle;

@@ -1050,7 +1050,7 @@

Entry = GDI_HANDLE_GET_ENTRY(HandleTable, ObjectHandle);
     Ret = Entry->KernelData != NULL &&
-          (Entry->Type & ~GDI_HANDLE_REUSE_MASK) != 0 &&
+          (Entry->Type & ~GDI_ENTRY_REUSE_MASK) != 0 &&
           (HANDLE)((ULONG_PTR)Entry->ProcessId & ~0x1) == ProcessId;

return Ret;
@@ -1060,7 +1060,7 @@
 }

BOOL INTERNAL_CALL
-GDIOBJ_ConvertToStockObj(PGDI_HANDLE_TABLE HandleTable, HGDIOBJ *hObj)
+GDIOBJ_ConvertToStockObj(PGDI_HANDLE_TABLE HandleTable, HGDIOBJ *phObj)
 {
 /*
  * FIXME !!!!! THIS FUNCTION NEEDS TO BE FIXED - IT IS NOT SAFE WHEN OTHER THREADS
@@ -1069,22 +1069,24 @@
   PGDI_TABLE_ENTRY Entry;
   HANDLE ProcessId, LockedProcessId, PrevProcId;
   PETHREAD Thread;
+  HGDIOBJ hObj;
 #ifdef GDI_DEBUG
   ULONG Attempts = 0;
 #endif

-  ASSERT(hObj);
-
-  DPRINT("GDIOBJ_ConvertToStockObj: hObj: 0x%08x\n", *hObj);
+  ASSERT(phObj);
+  hObj = *phObj;
+
+  DPRINT("GDIOBJ_ConvertToStockObj: hObj: 0x%08x\n", hObj);

Thread = PsGetCurrentThread();

-  if(!GDI_HANDLE_IS_STOCKOBJ(*hObj))
+  if(!GDI_HANDLE_IS_STOCKOBJ(hObj))
   {
     ProcessId = PsGetCurrentProcessId();
     LockedProcessId = (HANDLE)((ULONG_PTR)ProcessId | 0x1);

-    Entry = GDI_HANDLE_GET_ENTRY(HandleTable, *hObj);
+    Entry = GDI_HANDLE_GET_ENTRY(HandleTable, hObj);

LockHandle:
     /* lock the object, we must not convert stock objects, so don't check!!! */
@@ -1096,16 +1098,11 @@
       /* we're locking an object that belongs to our process. First calculate
          the new object type including the stock object flag and then try to
          exchange it.*/
-      /* FIXME: On Windows the higher 16 bit of the type field don't always match
-         the type from the handle, it is probably a storage type 
-         (type = pen, storage = brush) */
-      NewType = GDI_HANDLE_GET_TYPE(*hObj);
-      NewType |= GDI_HANDLE_GET_UPPER(*hObj) >> GDI_ENTRY_UPPER_SHIFT;
-
-      /* This is the type that the object should have right now, save it */
-      OldType = NewType;
+      OldType = ((ULONG)hObj & GDI_HANDLE_BASETYPE_MASK);
+      OldType |= GDI_HANDLE_GET_UPPER(hObj) >> GDI_ENTRY_UPPER_SHIFT;
+
       /* As the object should be a stock object, set it's flag, but only in the lower 16 bits */
-      NewType |= GDI_ENTRY_STOCK_MASK;
+      NewType = OldType | GDI_ENTRY_STOCK_MASK;

/* Try to exchange the type field - but only if the old (previous type) matches! */
       PrevType = InterlockedCompareExchange(&Entry->Type, NewType, OldType);
@@ -1146,7 +1143,8 @@
           /* remove the process id lock and make it global */
           (void)InterlockedExchangePointer(&Entry->ProcessId, GDI_GLOBAL_PROCESS);

-          *hObj = (HGDIOBJ)((ULONG)(*hObj) | GDI_HANDLE_STOCK_MASK);
+          hObj = (HGDIOBJ)((ULONG)(hObj) | GDI_HANDLE_STOCK_MASK);
+          *phObj = hObj;

/* we're done, successfully converted the object */
           return TRUE;