[NaCl SDK] Upate atomic ops in nacl_io

native_client_sdk/src/libraries/sdk_util/auto_lock.h

 /* Copyright (c) 2012 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.
  */
 
 #ifndef LIBRARIES_SDK_UTIL_AUTO_LOCK_H_
 #define LIBRARIES_SDK_UTIL_AUTO_LOCK_H_
 
 #include <pthread.h>
+#include "sdk_util/macros.h"
+#include "sdk_util/simple_lock.h"
+
+
+// This macro is provided to allow us to quickly instrument locking for
+// debugging purposes.
+#define AUTO_LOCK(lock)                         \
+  AutoLock Lock##__LINE__(lock);
 
 class AutoLock {
  public:
-  explicit AutoLock(pthread_mutex_t* lock) {
-    lock_ = lock;
+  AutoLock(const SimpleLock& lock) {
+    lock_ = lock.mutex();
     pthread_mutex_lock(lock_);
   }
+
   ~AutoLock() {
     if (lock_) pthread_mutex_unlock(lock_);
   }
 
   void Unlock() {
     if (lock_) pthread_mutex_unlock(lock_);
     lock_ = NULL;
   }
 
  private:
   pthread_mutex_t* lock_;
+
+  DISALLOW_COPY_AND_ASSIGN(AutoLock);
 };
 
 #endif  // LIBRARIES_SDK_UTIL_AUTO_LOCK_H_