Simplify implementation of Mutex.

test/cctest/test-lock.cc

 // Copyright 2006-2008 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 22 matching lines @@
 
 #include "platform.h"
 #include "cctest.h"
 
 
 using namespace ::v8::internal;
 
 
 // Simple test of locking logic
 TEST(Simple) {
-  Mutex* mutex = OS::CreateMutex();
-  CHECK_EQ(0, mutex->Lock());  // acquire the lock with the right token
-  CHECK_EQ(0, mutex->Unlock());  // can unlock with the right token
-  delete mutex;
-}
-
-
-TEST(MultiLock) {
-  Mutex* mutex = OS::CreateMutex();
-  CHECK_EQ(0, mutex->Lock());
-  CHECK_EQ(0, mutex->Unlock());
-  delete mutex;
+  Mutex mutex;
+  mutex.Lock();  // acquire the lock with the right token
+  mutex.Unlock();  // can unlock with the right token
 }
 
 
 TEST(ShallowLock) {
-  Mutex* mutex = OS::CreateMutex();
-  CHECK_EQ(0, mutex->Lock());
-  CHECK_EQ(0, mutex->Unlock());
-  CHECK_EQ(0, mutex->Lock());
-  CHECK_EQ(0, mutex->Unlock());
-  delete mutex;
+  Mutex mutex;
+  mutex.Lock();
+  mutex.Unlock();
+  mutex.Lock();
+  mutex.Unlock();
 }
 
 
 TEST(SemaphoreTimeout) {
   bool ok;
   Semaphore* sem = OS::CreateSemaphore(0);
 
   // Semaphore not signalled - timeout.
   ok = sem->Wait(0);
   CHECK(!ok);
   ok = sem->Wait(100);
   CHECK(!ok);
   ok = sem->Wait(1000);
   CHECK(!ok);
 
   // Semaphore signalled - no timeout.
   sem->Signal();
   ok = sem->Wait(0);
   sem->Signal();
   ok = sem->Wait(100);
   sem->Signal();
   ok = sem->Wait(1000);
   CHECK(ok);
   delete sem;
 }