chrome/common/importer/ie_importer_test_registry_overrider_win.cc

   1 // Copyright (c) 2013 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "chrome/common/importer/ie_importer_test_registry_overrider_win.h"
   6
   7 #include <windows.h>
   8
   9 #include <string>
  10
  11 #include "base/environment.h"
  12 #include "base/guid.h"
  13 #include "base/memory/scoped_ptr.h"
  14 #include "base/strings/utf_string_conversions.h"
  15 #include "base/win/registry.h"
  16
  17 namespace {
  18
  19 // The key to which a random subkey will be appended. This key itself will never
  20 // be deleted.
  21 const wchar_t kTestHKCUOverrideKeyPrefix[] = L"SOFTWARE\\Chromium Unit Tests\\";
  22 const char kTestHKCUOverrideEnvironmentVariable[] =
  23     "IE_IMPORTER_TEST_OVERRIDE_HKCU";
  24
  25 // Reads the environment variable set by a previous call to
  26 // SetTestRegistryOverride() into |key| if it exists and |key| is not NULL.
  27 // Returns true if the variable was successfully read.
  28 bool GetTestKeyFromEnvironment(base::string16* key) {
  29   scoped_ptr<base::Environment> env(base::Environment::Create());
  30   std::string value;
  31   bool result = env->GetVar(kTestHKCUOverrideEnvironmentVariable, &value);
  32   if (result)
  33     *key = base::UTF8ToUTF16(value);
  34   return result;
  35 }
  36
  37 }  // namespace
  38
  39 ////////////////////////////////////////////////////////////////////////////////
  40 // IEImporterTestRegistryOverrider, public:
  41
  42 IEImporterTestRegistryOverrider::IEImporterTestRegistryOverrider()
  43     : temporary_key_(kTestHKCUOverrideKeyPrefix +
  44                      base::UTF8ToUTF16(base::GenerateGUID())) {
  45   DCHECK(!GetTestKeyFromEnvironment(NULL));
  46
  47   scoped_ptr<base::Environment> env(base::Environment::Create());
  48   bool success = env->SetVar(kTestHKCUOverrideEnvironmentVariable,
  49                              base::UTF16ToUTF8(temporary_key_));
  50   DCHECK(success);
  51 }
  52
  53 IEImporterTestRegistryOverrider::~IEImporterTestRegistryOverrider() {
  54   base::win::RegKey reg_key(HKEY_CURRENT_USER, temporary_key_.c_str(),
  55                             KEY_ALL_ACCESS);
  56   DCHECK(reg_key.Valid());
  57   reg_key.DeleteKey(L"");
  58
  59   scoped_ptr<base::Environment> env(base::Environment::Create());
  60   bool success = env->UnSetVar(kTestHKCUOverrideEnvironmentVariable);
  61   DCHECK(success);
  62 }
  63
  64 // static
  65 base::string16 IEImporterTestRegistryOverrider::GetTestRegistryOverride() {
  66   base::string16 key;
  67   if (!GetTestKeyFromEnvironment(&key))
  68     return base::string16();
  69   return key;
  70 }