Regkey functions return error code instead of bool

net/base/platform_mime_util_win.cc

 // Copyright (c) 2010 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 <string>
 
 #include "net/base/platform_mime_util.h"
 
 #include "base/utf_string_conversions.h"
 #include "base/win/registry.h"
 
 namespace net {
 
 bool PlatformMimeUtil::GetPlatformMimeTypeFromExtension(
     const FilePath::StringType& ext, std::string* result) const {
   // check windows registry for file extension's mime type (registry key
   // names are not case-sensitive).
   std::wstring value, key = L"." + ext;
-  base::win::RegKey(HKEY_CLASSES_ROOT, key.c_str(), KEY_READ).ReadValue(
-      L"Content Type", &value);
+  base::win::RegKey mime_key;
+  LONG ret = mime_key.Open(HKEY_CLASSES_ROOT, key.c_str(), KEY_READ);
+  if (ret == ERROR_SUCCESS)
+    ret = mime_key.ReadValue(L"Content Type", &value);
   if (!value.empty()) {
     *result = WideToUTF8(value);
     return true;
   }
   return false;
 }
 
 bool PlatformMimeUtil::GetPreferredExtensionForMimeType(
     const std::string& mime_type, FilePath::StringType* ext) const {
   std::wstring key(L"MIME\\Database\\Content Type\\" + UTF8ToWide(mime_type));
-  if (!base::win::RegKey(HKEY_CLASSES_ROOT, key.c_str(), KEY_READ).ReadValue(
-          L"Extension", ext)) {
+  base::win::RegKey extension_key;
+  LONG ret = extension_key.Open(HKEY_CLASSES_ROOT, key.c_str(), KEY_READ);
+  if (ret == ERROR_SUCCESS)
+    ret = extension_key.ReadValue(L"Extension", ext);
+  if (ret != ERROR_SUCCESS) {

[robertshield, 2011/01/12 15:01:34]

nit: how about

if (extension_key.Open(HKEY_CLASSES_ROOT, key.c_str(),
                       KEY_READ) != ERROR_SUCCESS ||
    extension_key.ReadValue(L"Extension", ext) != ERROR_SUCCESS) {
  return false;
}

     return false;
   }
   // Strip off the leading dot, this should always be the case.
   if (!ext->empty() && ext->at(0) == L'.')
     ext->erase(ext->begin());
 
   return true;
 }
 
 }  // namespace net