setupapi: Respect samDesired in SetupDiOpenClassRegKeyExW.

dlls/setupapi/devinst.c

@@ -2337,7 +2337,6 @@ HKEY WINAPI SetupDiOpenClassRegKeyExW(
         PCWSTR MachineName,
         PVOID Reserved)
 {
-    WCHAR bracedGuidString[39];
     HKEY hClassesKey;
     HKEY hClassKey;
     LPCWSTR lpKeyName;
@@ -2363,24 +2362,36 @@ HKEY WINAPI SetupDiOpenClassRegKeyExW(
         return INVALID_HANDLE_VALUE;
     }
 
+    if (!ClassGuid)
+    {
         if (RegOpenKeyExW(HKEY_LOCAL_MACHINE,
                           lpKeyName,
                           0,
-		      KEY_ALL_ACCESS,
+                          samDesired,
                           &hClassesKey))
         {
             return INVALID_HANDLE_VALUE;
         }
-
-    if (ClassGuid == NULL)
         return hClassesKey;
+    }
+    else
+    {
+        WCHAR bracedGuidString[39];
 
         SETUPDI_GuidToString(ClassGuid, bracedGuidString);
 
+        if (RegOpenKeyExW(HKEY_LOCAL_MACHINE,
+                          lpKeyName,
+                          0,
+                          samDesired,
+                          &hClassesKey))
+        {
+            return INVALID_HANDLE_VALUE;
+        }
         if (RegOpenKeyExW(hClassesKey,
                           bracedGuidString,
                           0,
-		      KEY_ALL_ACCESS,
+                          samDesired,
                           &hClassKey))
         {
             RegCloseKey(hClassesKey);
@@ -2390,6 +2401,7 @@ HKEY WINAPI SetupDiOpenClassRegKeyExW(
         RegCloseKey(hClassesKey);
 
         return hClassKey;
+    }
 }
 
 /***********************************************************************