Move ScopedTokenPrivilege to chrome/installer/util

chrome/installer/util/scoped_token_privilege.cc

+// Copyright 2017 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/installer/util/scoped_token_privilege.h"
+
+ScopedTokenPrivilege::ScopedTokenPrivilege(const wchar_t* privilege_name)
+    : is_enabled_(false) {
+  HANDLE temp_handle;
+  if (!::OpenProcessToken(::GetCurrentProcess(),
+                          TOKEN_ADJUST_PRIVILEGES | TOKEN_QUERY,
+                          &temp_handle)) {
+    return;
+  }
+  token_.Set(temp_handle);
+
+  LUID privilege_luid;
+  if (!::LookupPrivilegeValue(NULL, privilege_name, &privilege_luid)) {
+    token_.Close();
+    return;
+  }
+
+  // Adjust the token's privileges to enable |privilege_name|. If this privilege
+  // was already enabled, |previous_privileges_|.PrivilegeCount will be set to 0
+  // and we then know not to disable this privilege upon destruction.
+  TOKEN_PRIVILEGES tp;
+  tp.PrivilegeCount = 1;
+  tp.Privileges[0].Luid = privilege_luid;
+  tp.Privileges[0].Attributes = SE_PRIVILEGE_ENABLED;
+  DWORD return_length;
+  if (!::AdjustTokenPrivileges(token_.Get(), FALSE, &tp,
+                               sizeof(TOKEN_PRIVILEGES), &previous_privileges_,
+                               &return_length)) {
+    token_.Close();
+    return;
+  }
+
+  is_enabled_ = true;
+}
+
+ScopedTokenPrivilege::~ScopedTokenPrivilege() {
+  if (is_enabled_ && previous_privileges_.PrivilegeCount != 0) {
+    ::AdjustTokenPrivileges(token_.Get(), FALSE, &previous_privileges_,
+                            sizeof(TOKEN_PRIVILEGES), NULL, NULL);
+  }
+}