oledb32: Source status DBSTATUS_S_ISNULL applies to all conversions.

dlls/oledb32/convert.c

@@ -184,6 +184,13 @@ static HRESULT WINAPI convert_DataConvert(IDataConvert* iface,
         return DB_E_UNSUPPORTEDCONVERSION;
     }
 
+    if(src_status == DBSTATUS_S_ISNULL)
+    {
+        *dst_status = DBSTATUS_S_ISNULL;
+        *dst_len = 0;
+        return S_OK;
+    }
+
     if(src_type == DBTYPE_STR)
     {
         BSTR b;
@@ -805,13 +812,6 @@ static HRESULT WINAPI convert_DataConvert(IDataConvert* iface,
     {
         VARIANT *v = dst;
 
-        if(src_status == DBSTATUS_S_ISNULL)
-        {
-            *dst_status = DBSTATUS_S_ISNULL;
-            *dst_len = 0;
-            return S_OK;
-        }
-
         switch(src_type)
         {
         case DBTYPE_BOOL:

dlls/oledb32/tests/convert.c

@@ -884,6 +884,14 @@ todo_wine
     ok(dst_status == DBSTATUS_S_OK, "got %08x\n", dst_status);
     ok(dst_len == sizeof(i4), "got %ld\n", dst_len);
     ok(i4 == 10, "got %08x\n", i4);
+
+    /* src_status = DBSTATUS_S_ISNULL */
+    i4 = 0x12345678;
+    hr = IDataConvert_DataConvert(convert, DBTYPE_I4, DBTYPE_I4, 0, &dst_len, src, &i4, sizeof(i4), DBSTATUS_S_ISNULL, &dst_status, 0, 0, 0);
+    ok(hr == S_OK, "got %08x\n", hr);
+    ok(dst_status == DBSTATUS_S_ISNULL, "got %08x\n", dst_status);
+    ok(dst_len == 0, "got %ld\n", dst_len);
+
 }
 
 static void test_converttoi8(void)