DC hook proc thunk management simplified.

if1632/gdi.spec

@@ -157,8 +157,8 @@ file	gdi.exe
 180 pascal16 SetDCState(word word) SetDCState16
 181 pascal16 RectInRegionOld(word ptr) RectInRegion16
 188 stub GetTextExtentEx
-190 pascal16 SetDCHook(word segptr long) THUNK_SetDCHook
-191 pascal   GetDCHook(word ptr) THUNK_GetDCHook
+190 pascal16 SetDCHook(word segptr long) SetDCHook
+191 pascal   GetDCHook(word ptr) GetDCHook
 192 pascal16 SetHookFlags(word word) SetHookFlags16
 193 pascal16 SetBoundsRect(word ptr word) SetBoundsRect16
 194 pascal16 GetBoundsRect(word ptr word) GetBoundsRect16

include/gdi.h

@@ -137,6 +137,9 @@ typedef struct
     BOOL          vport2WorldValid;  /* Is xformVport2World valid? */
 } WIN_DC_INFO;
 
+
+typedef BOOL16 (CALLBACK *DCHOOKPROC)(HDC16,WORD,DWORD,LPARAM);
+
 typedef struct tagDC
 {
     GDIOBJHDR    header;
@@ -145,7 +148,8 @@ typedef struct tagDC
     void         *physDev;         /* Physical device (driver-specific) */
     INT          saveLevel;
     DWORD        dwHookData;
-    FARPROC16      hookProc;
+    FARPROC16    hookProc;         /* the original SEGPTR ... */
+    DCHOOKPROC   hookThunk;        /* ... and the thunk to call it */
 
     INT          wndOrgX;          /* Window origin */
     INT          wndOrgY;

objects/.cvsignore

 Makefile
+dc.glue.c

objects/Makefile.in

@@ -24,6 +24,8 @@ C_SRCS = \
 	region.c \
 	text.c
 
+GLUE = dc.c
+
 all: $(MODULE).o
 
 @MAKE_RULES@

objects/clipping.c

@@ -15,8 +15,8 @@ DECLARE_DEBUG_CHANNEL(region)
 
 #define UPDATE_DIRTY_DC(dc) \
  do { \
-   if ((dc)->hookProc && !((dc)->w.flags & (DC_SAVED | DC_MEMORY))) \
-     (dc)->hookProc( (dc)->hSelf, DCHC_INVALIDVISRGN, (dc)->dwHookData, 0 ); \
+   if ((dc)->hookThunk && !((dc)->w.flags & (DC_SAVED | DC_MEMORY))) \
+     (dc)->hookThunk( (dc)->hSelf, DCHC_INVALIDVISRGN, (dc)->dwHookData, 0 ); \
  } while(0)
 
 

objects/dc.c

@@ -99,6 +99,7 @@ DC *DC_AllocDC( const DC_FUNCTIONS *funcs )
     dc->saveLevel  = 0;
     dc->dwHookData = 0L;
     dc->hookProc   = NULL;
+    dc->hookThunk  = NULL;
     dc->wndOrgX    = 0;
     dc->wndOrgY    = 0;
     dc->wndExtX    = 1;
@@ -680,8 +681,8 @@ BOOL WINAPI DeleteDC( HDC hdc )
     TRACE("%04x\n", hdc );
 
     /* Call hook procedure to check whether is it OK to delete this DC */
-    if (    dc->hookProc && !(dc->w.flags & (DC_SAVED | DC_MEMORY))
-         && dc->hookProc( hdc, DCHC_DELETEDC, dc->dwHookData, 0 ) == FALSE )
+    if (    dc->hookThunk && !(dc->w.flags & (DC_SAVED | DC_MEMORY))
+         && dc->hookThunk( hdc, DCHC_DELETEDC, dc->dwHookData, 0 ) == FALSE )
     {
         GDI_HEAP_UNLOCK( hdc );
         return FALSE;
@@ -710,6 +711,7 @@ BOOL WINAPI DeleteDC( HDC hdc )
     if (dc->w.hVisRgn) DeleteObject( dc->w.hVisRgn );
     if (dc->w.hGCClipRgn) DeleteObject( dc->w.hGCClipRgn );
     if (dc->w.pAbortProc) THUNK_Free( (FARPROC)dc->w.pAbortProc );
+    if (dc->hookThunk) THUNK_Free( (FARPROC)dc->hookThunk );
     PATH_DestroyGdiPath(&dc->w.path);
     
     return GDI_FreeObject( hdc );
@@ -1201,16 +1203,35 @@ BOOL WINAPI CombineTransform( LPXFORM xformResult, const XFORM *xform1,
 /***********************************************************************
  *           SetDCHook   (GDI.190)
  */
+/* ### start build ### */
+extern WORD CALLBACK GDI_CallTo16_word_wwll(FARPROC16,WORD,WORD,LONG,LONG);
+/* ### stop build ### */
 BOOL16 WINAPI SetDCHook( HDC16 hdc, FARPROC16 hookProc, DWORD dwHookData )
 {
     DC *dc = (DC *)GDI_GetObjPtr( hdc, DC_MAGIC );
+    if (!dc) return FALSE;
 
-    TRACE("hookProc %08x, default is %08x\n",
-                (UINT)hookProc, (UINT)DCHook16 );
+    /*
+     * Note: We store the original SEGPTR 'hookProc' as we need to be
+     *       able to return it verbatim in GetDCHook,
+     *
+     *       On the other hand, we still call THUNK_Alloc and store the
+     *       32-bit thunk into another DC member, because THUNK_Alloc
+     *       recognizes the (typical) case that the 'hookProc' is indeed
+     *       the 16-bit API entry point of a built-in routine (e.g. DCHook16)
+     *
+     *       We could perform that test every time the hook is about to
+     *       be called (or else we could live with the 32->16->32 detour),
+     *       but this way is the most efficient ...
+     */
 
-    if (!dc) return FALSE;
     dc->hookProc = hookProc;
     dc->dwHookData = dwHookData;
+
+    THUNK_Free( (FARPROC)dc->hookThunk );
+    dc->hookThunk = (DCHOOKPROC)
+                    THUNK_Alloc( hookProc, (RELAY)GDI_CallTo16_word_wwll );
+
     GDI_HEAP_UNLOCK( hdc );
     return TRUE;
 }

windows/dce.c

@@ -27,7 +27,9 @@
 #include "region.h"
 #include "heap.h"
 #include "local.h"
+#include "module.h"
 #include "debugtools.h"
+#include "wine/winbase16.h"
 #include "wine/winuser16.h"
 
 DEFAULT_DEBUG_CHANNEL(dc)
@@ -71,6 +73,7 @@ static void DCE_DumpCache(void)
  */
 DCE *DCE_AllocDCE( HWND hWnd, DCE_TYPE type )
 {
+    FARPROC16 hookProc;
     DCE * dce;
     WND* wnd;
     
@@ -85,7 +88,8 @@ DCE *DCE_AllocDCE( HWND hWnd, DCE_TYPE type )
     
     /* store DCE handle in DC hook data field */
 
-    SetDCHook( dce->hDC, (FARPROC16)DCHook16, (DWORD)dce );
+    hookProc = (FARPROC16)NE_GetEntryPoint( GetModuleHandle16("USER"), 362 );
+    SetDCHook( dce->hDC, hookProc, (DWORD)dce );
 
     dce->hwndCurrent = hWnd;
     dce->hClipRgn    = 0;