- return a precomputed result for a NULL string

dlls/ole32/compobj.c

@@ -813,27 +813,29 @@ HRESULT WINAPI CoCreateGuid(GUID *pguid)
  */
 HRESULT WINAPI __CLSIDFromStringA(LPCSTR idstr, CLSID *id)
 {
-  const BYTE *s = (const BYTE *) idstr;
+  const BYTE *s;
   int	i;
   BYTE table[256];
 
-  if (!s)
-	  s = "{00000000-0000-0000-0000-000000000000}";
-  else {  /* validate the CLSID string */
+  if (!idstr) {
+    memset( id, 0, sizeof (CLSID) );
+    return S_OK;
+  }
 
-      if (strlen(s) != 38)
-          return CO_E_CLASSSTRING;
+  /* validate the CLSID string */
+  if (strlen(idstr) != 38)
+    return CO_E_CLASSSTRING;
 
-      if ((s[0]!='{') || (s[9]!='-') || (s[14]!='-') || (s[19]!='-') || (s[24]!='-') || (s[37]!='}'))
-          return CO_E_CLASSSTRING;
+  s = (const BYTE *) idstr;
+  if ((s[0]!='{') || (s[9]!='-') || (s[14]!='-') || (s[19]!='-') || (s[24]!='-') || (s[37]!='}'))
+    return CO_E_CLASSSTRING;
 
-      for (i=1; i<37; i++) {
-          if ((i == 9)||(i == 14)||(i == 19)||(i == 24)) continue;
-          if (!(((s[i] >= '0') && (s[i] <= '9'))  ||
-                ((s[i] >= 'a') && (s[i] <= 'f'))  ||
-                ((s[i] >= 'A') && (s[i] <= 'F'))))
-              return CO_E_CLASSSTRING;
-      }
+  for (i=1; i<37; i++) {
+    if ((i == 9)||(i == 14)||(i == 19)||(i == 24)) continue;
+    if (!(((s[i] >= '0') && (s[i] <= '9'))  ||
+          ((s[i] >= 'a') && (s[i] <= 'f'))  ||
+          ((s[i] >= 'A') && (s[i] <= 'F'))))
+       return CO_E_CLASSSTRING;
   }
 
   TRACE("%s -> %p\n", s, id);