| // Copyright (c) 2011 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/synchronization/lock_impl.h" | 
 |  | 
 | namespace base { | 
 | namespace internal { | 
 |  | 
 | LockImpl::LockImpl() { | 
 |   // The second parameter is the spin count, for short-held locks it avoid the | 
 |   // contending thread from going to sleep which helps performance greatly. | 
 |   ::InitializeCriticalSectionAndSpinCount(&native_handle_, 2000); | 
 | } | 
 |  | 
 | LockImpl::~LockImpl() { | 
 |   ::DeleteCriticalSection(&native_handle_); | 
 | } | 
 |  | 
 | bool LockImpl::Try() { | 
 |   if (::TryEnterCriticalSection(&native_handle_) != FALSE) { | 
 |     return true; | 
 |   } | 
 |   return false; | 
 | } | 
 |  | 
 | void LockImpl::Lock() { | 
 |   ::EnterCriticalSection(&native_handle_); | 
 | } | 
 |  | 
 | void LockImpl::Unlock() { | 
 |   ::LeaveCriticalSection(&native_handle_); | 
 | } | 
 |  | 
 | }  // namespace internal | 
 | }  // namespace base |