Cleanup common POSIX functionality.

src/platform-macos.cc

Index: src/platform-macos.cc
diff --git a/src/platform-macos.cc b/src/platform-macos.cc
index f4d8b33817990f918c4d25eefbbcf453702f91b2..e8c25fae93ad0cce3ec54a96a50270fc762c47f8 100644
--- a/src/platform-macos.cc
+++ b/src/platform-macos.cc
@@ -652,45 +652,6 @@ void Thread::SetThreadLocal(LocalStorageKey key, void* value) {
 }
 
 
-void Thread::YieldCPU() {
-  sched_yield();
-}
-
-
-class MacOSMutex : public Mutex {
- public:
-  MacOSMutex() {
-    pthread_mutexattr_t attr;
-    pthread_mutexattr_init(&attr);
-    pthread_mutexattr_settype(&attr, PTHREAD_MUTEX_RECURSIVE);
-    pthread_mutex_init(&mutex_, &attr);

[Dmitry Lomov (no reviews), 2013/07/11 10:52:16]

Hmm MacOS mutex did not have pthread_mutexattr_destroy before, but it should be
fine.

[Benedikt Meurer, 2013/07/11 10:58:45]

Yeah, it's currently a no-op on OS X, but that might change in the future, so we
should do proper cleanup.

-  }
-
-  virtual ~MacOSMutex() { pthread_mutex_destroy(&mutex_); }
-
-  virtual int Lock() { return pthread_mutex_lock(&mutex_); }
-  virtual int Unlock() { return pthread_mutex_unlock(&mutex_); }
-
-  virtual bool TryLock() {
-    int result = pthread_mutex_trylock(&mutex_);
-    // Return false if the lock is busy and locking failed.
-    if (result == EBUSY) {
-      return false;
-    }
-    ASSERT(result == 0);  // Verify no other errors.
-    return true;
-  }
-
- private:
-  pthread_mutex_t mutex_;
-};
-
-
-Mutex* OS::CreateMutex() {
-  return new MacOSMutex();
-}
-
-
 class MacOSSemaphore : public Semaphore {
  public:
   explicit MacOSSemaphore(int count) {