Simplify implementation of Mutex.

src/platform.h

 // Copyright 2012 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 82 matching lines @@
 
 #endif  // _MSC_VER
 
 #ifndef __CYGWIN__
 // Random is missing on both Visual Studio and MinGW.
 int random();
 #endif
 
 #endif  // WIN32
 
-#include "lazy-instance.h"
+#include "mutex.h"
 #include "utils.h"
 #include "v8globals.h"
 
 namespace v8 {
 namespace internal {
 
 class Semaphore;
 class Mutex;
 
 double ceiling(double x);
@@ skipping 188 matching lines @@
   static const int kStackWalkError = -1;
   static const int kStackWalkMaxNameLen = 256;
   static const int kStackWalkMaxTextLen = 256;
   struct StackFrame {
     void* address;
     char text[kStackWalkMaxTextLen];
   };
 
   static int StackWalk(Vector<StackFrame> frames);
 
-  // Factory method for creating platform dependent Mutex.
-  // Please use delete to reclaim the storage for the returned Mutex.
-  static Mutex* CreateMutex();
-
   // Factory method for creating platform dependent Semaphore.
   // Please use delete to reclaim the storage for the returned Semaphore.
   static Semaphore* CreateSemaphore(int count);
 
   // Factory method for creating platform dependent Socket.
   // Please use delete to reclaim the storage for the returned Socket.
   static Socket* CreateSocket();
 
   class MemoryMappedFile {
    public:
@@ skipping 383 matching lines @@
 
   char name_[kMaxThreadNameLength];
   int stack_size_;
   Semaphore* start_semaphore_;
 
   DISALLOW_COPY_AND_ASSIGN(Thread);
 };
 
 
 // ----------------------------------------------------------------------------
-// Mutex
-//
-// Mutexes are used for serializing access to non-reentrant sections of code.
-// The implementations of mutex should allow for nested/recursive locking.
-
-class Mutex {
- public:
-  virtual ~Mutex() {}
-
-  // Locks the given mutex. If the mutex is currently unlocked, it becomes
-  // locked and owned by the calling thread, and immediately. If the mutex
-  // is already locked by another thread, suspends the calling thread until
-  // the mutex is unlocked.
-  virtual int Lock() = 0;
-
-  // Unlocks the given mutex. The mutex is assumed to be locked and owned by
-  // the calling thread on entrance.
-  virtual int Unlock() = 0;
-
-  // Tries to lock the given mutex. Returns whether the mutex was
-  // successfully locked.
-  virtual bool TryLock() = 0;
-};
-
-struct CreateMutexTrait {
-  static Mutex* Create() {
-    return OS::CreateMutex();
-  }
-};
-
-// POD Mutex initialized lazily (i.e. the first time Pointer() is called).
-// Usage:
-//   static LazyMutex my_mutex = LAZY_MUTEX_INITIALIZER;
-//
-//   void my_function() {
-//     ScopedLock my_lock(my_mutex.Pointer());
-//     // Do something.
-//   }
-//
-typedef LazyDynamicInstance<
-    Mutex, CreateMutexTrait, ThreadSafeInitOnceTrait>::type LazyMutex;
-
-#define LAZY_MUTEX_INITIALIZER LAZY_DYNAMIC_INSTANCE_INITIALIZER
-
-// ----------------------------------------------------------------------------
-// ScopedLock
-//
-// Stack-allocated ScopedLocks provide block-scoped locking and
-// unlocking of a mutex.
-class ScopedLock {
- public:
-  explicit ScopedLock(Mutex* mutex): mutex_(mutex) {
-    ASSERT(mutex_ != NULL);
-    mutex_->Lock();
-  }
-  ~ScopedLock() {
-    mutex_->Unlock();
-  }
-
- private:
-  Mutex* mutex_;
-  DISALLOW_COPY_AND_ASSIGN(ScopedLock);
-};
-
-
-// ----------------------------------------------------------------------------
 // Socket
 //
 
 class Socket {
  public:
   virtual ~Socket() {}
 
   // Server initialization.
   virtual bool Bind(const int port) = 0;
   virtual bool Listen(int backlog) const = 0;
@@ skipping 22 matching lines @@
   static uint16_t HToN(uint16_t value);
   static uint16_t NToH(uint16_t value);
   static uint32_t HToN(uint32_t value);
   static uint32_t NToH(uint32_t value);
 };
 
 
 } }  // namespace v8::internal
 
 #endif  // V8_PLATFORM_H_