Local USER classes act as global

[Joshua Thielen]

Hello,

When I checked out the latest CVS, all the dialog boxes in Finale 
stopped working (again) . This happened since Alexandre fixed a function 
call from GetModuleHandleA("USER") to GetModuleHandle16("USER") in my 
previous GetClassInfo16 patch (thanks Alexnadre!). My patch had worked 
because GetModuleHandleA returned hInstance 0 for USER and Finale would 
proceed to register a window class with hInstance 0. Since classes with 
hInst=0 are treated sort of like global classes in wine, the window 
class was found.

After more investigating, I discovered that in Win16, any window class 
that is registered with a USER instance handle will be found even if the 
hInstance passed to the function (GetClassInfo, CreateWindow etv c.) is 
completely different. This happens even for classes without the 
CS_GLOBALCLASS style. I have some small test apps if anyone is intrigued 
by this. Anyway, this patch implements this undocumented bug, uh.. er.. 
feature in wine and gets Finale working again .

Changelog:
Local classes registered with USER instance handle now are now found in 
CLASS_FindClassByAtom.

Modified Files:
wine/windows/wnd16.c

Josh Thielen

Index: wine/windows/class.c
===================================================================
RCS file: /home/wine/wine/windows/class.c,v
retrieving revision 1.42
diff -u -r1.42 class.c
--- wine/windows/class.c	2001/11/06 20:57:27	1.42
+++ wine/windows/class.c	2001/11/13 23:23:39
@@ -279,10 +279,14 @@
  * NOTES
  *  980805 a local class will be found now if registred with hInst=0
  *  and looed up with a hInst!=0. msmoney does it (jsch)
+ *  
+ *  Local class registered with a USER instance handle are found as if 
+ *  they were global classes.
  */
 static CLASS *CLASS_FindClassByAtom( ATOM atom, HINSTANCE hinstance )
 {
-    CLASS * class, *tclass=0;
+    CLASS * class, *tclass = 0, *user_class = 0;
+    HINSTANCE hUser = GetModuleHandle16("USER");

TRACE("0x%08x 0x%08x\n", atom, hinstance);

@@ -293,16 +297,20 @@
         if (class->style & CS_GLOBALCLASS) continue;
         if (class->atomName == atom)
         {
-            if (hinstance==class->hInstance || hinstance==0xffff )
+            if (hinstance==class->hInstance || hinstance==0xffff)
             {
                 TRACE("-- found local %p\n", class);
                 return class;
             }
-            if (class->hInstance==0) tclass = class;
+            if (class->hInstance == 0) tclass = class;
+            else if(class->hInstance == hUser)
+            {
+                user_class = class;
+            }
         }
     }

-      /* Then search global classes */
+    /* Then search global classes */

for (class = firstClass; (class); class = class->next)
     {
@@ -312,6 +320,13 @@
             TRACE("-- found global %p\n", class);
             return class;
         }
+    }
+
+    /* Check if there was a local class registered with USER */
+    if( user_class )
+    {
+        TRACE("--found local USER class %p\n", user_class);
+        return user_class;
     }

/* Then check if there was a local class with hInst=0*/