| // Copyright (c) 2012 The Chromium Authors. All rights reserved. | 
 | // Use of this source code is governed by a BSD-style license that can be | 
 | // found in the LICENSE file. | 
 |  | 
 | #include "base/guid.h" | 
 |  | 
 | #include "base/strings/string_util.h" | 
 |  | 
 | namespace base { | 
 |  | 
 | bool IsValidGUID(const std::string& guid) { | 
 |   const size_t kGUIDLength = 36U; | 
 |   if (guid.length() != kGUIDLength) | 
 |     return false; | 
 |  | 
 |   for (size_t i = 0; i < guid.length(); ++i) { | 
 |     char current = guid[i]; | 
 |     if (i == 8 || i == 13 || i == 18 || i == 23) { | 
 |       if (current != '-') | 
 |         return false; | 
 |     } else { | 
 |       if (!IsHexDigit(current)) | 
 |         return false; | 
 |     } | 
 |   } | 
 |  | 
 |   return true; | 
 | } | 
 |  | 
 | }  // namespace base |