Introduce IEImporterTestRegistryOverrider to be able to override the registry for a test and flag t…

chrome/browser/importer/ie_importer_test_registry_overrider_win.cc

+// Copyright (c) 2013 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 "chrome/browser/importer/ie_importer_test_registry_overrider_win.h"
+
+#include <windows.h>
+#include <processenv.h>
+
+#include "base/string16.h"
+#include "base/win/registry.h"
+
+namespace {
+
+const char16 kTestHKCUOverrideKey[] = L"SOFTWARE\\Chromium Unit Tests";
+const char16 kTestHKCUOverrideSubKey[] =
+    L"SOFTWARE\\Chromium Unit Tests\\HKCU Override";
+const char16 kTestHKCUOverrideEnvironmentVariable[] =
+    L"IE_IMPORTER_TEST_OVERRIDE_HKCU";
+const char16 kTestHKCUOverrideEnvironmentVariableValue[] =

[robertshield, 2013/04/26 19:20:53]

nit: don't wrap

[gab, 2013/04/29 02:00:43]

Done.

+    L"1";
+
+}  // namespace
+
+////////////////////////////////////////////////////////////////////////////////
+// IEImporterTestRegistryOverrider, public:
+
+IEImporterTestRegistryOverrider::~IEImporterTestRegistryOverrider() {
+  if (override_active_) {
+    if (RegOverridePredefKey(HKEY_CURRENT_USER, NULL) != ERROR_SUCCESS)
+      LOG(ERROR) << "Failed to unset registry override";
+
+    if (override_set_by_current_process_) {
+      base::win::RegKey key(HKEY_CURRENT_USER, kTestHKCUOverrideKey,
+                            KEY_ALL_ACCESS);
+      key.DeleteKey(L"");
+    }
+  }
+}
+
+bool IEImporterTestRegistryOverrider::SetRegistryOverride() {
+  override_set_by_current_process_ = true;
+  return StartRegistryOverride() &&
+      ::SetEnvironmentVariable(kTestHKCUOverrideEnvironmentVariable,
+                               kTestHKCUOverrideEnvironmentVariableValue) != 0;

[robertshield, 2013/04/26 19:20:53]

use the stuff in base\environment.h here

[gab, 2013/04/29 02:00:43]

Done.

+}
+
+bool IEImporterTestRegistryOverrider::StartRegistryOverrideIfNeeded() {
+  char16 buffer[arraysize(kTestHKCUOverrideEnvironmentVariableValue)];
+  DWORD result = ::GetEnvironmentVariable(
+                     kTestHKCUOverrideEnvironmentVariable, buffer,
+                     arraysize(buffer));

[robertshield, 2013/04/26 19:20:53]

use the stuff in base\environment.h here

[gab, 2013/04/29 02:00:43]

Done.

+  if (result == 1 &&
+      buffer[0] == kTestHKCUOverrideEnvironmentVariableValue[0]) {
+    // If the variable was set, GetEnvironmentVariable should read it into
+    // |buffer| and return the size of the string read (without the
+    // null-terminating character).
+    return StartRegistryOverride();
+  } else {
+    // Failing to read the value should mean it was not found.
+    return ::GetLastError() == ERROR_ENVVAR_NOT_FOUND;
+  }
+}
+
+////////////////////////////////////////////////////////////////////////////////
+// IEImporterTestRegistryOverrider, private:
+
+bool IEImporterTestRegistryOverrider::StartRegistryOverride() {
+  base::win::RegKey temp_hkcu_hive_key;
+  DWORD result = temp_hkcu_hive_key.Create(HKEY_CURRENT_USER,
+                                           kTestHKCUOverrideSubKey,
+                                           KEY_ALL_ACCESS);
+  if (result != ERROR_SUCCESS || !temp_hkcu_hive_key.Valid()) {
+    DPLOG(ERROR) << result;
+    return false;
+  }
+
+  override_active_ = true;
+  return RegOverridePredefKey(HKEY_CURRENT_USER,
+                              temp_hkcu_hive_key.Handle()) == ERROR_SUCCESS;
+}