Torque2D/engine/source/platform/threads/semaphore.h

//-----------------------------------------------------------------------------
// Copyright (c) 2013 GarageGames, LLC
//
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// of this software and associated documentation files (the "Software"), to
// deal in the Software without restriction, including without limitation the
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// sell copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
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// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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//-----------------------------------------------------------------------------

#ifndef _PLATFORM_THREAD_SEMAPHORE_H_
#define _PLATFORM_THREAD_SEMAPHORE_H_

#ifndef _TORQUE_TYPES_H_
#include "platform/types.h"
#endif

// Forward ref used by platform code
struct PlatformSemaphore;

class Semaphore
{
protected:
   PlatformSemaphore *mData;
public:
   /// Create a semaphore. initialCount defaults to 1.
   Semaphore(S32 initialCount = 1);
   /// Delete a semaphore, ignoring it's count.
   ~Semaphore();

   /// Acquire the semaphore, decrementing its count.
   /// if the initial count is less than 1, block until it goes above 1, then acquire.
   /// Returns true if the semaphore was acquired, false if the semaphore could
   /// not be acquired and block was false.
   bool acquire(bool block = true, S32 timeoutMS = -1);
   
   /// Release the semaphore, incrementing its count.
   /// Never blocks.
   void release();
   
   // Old API so that we don't have to change a load of code
   static void* createSemaphore(U32 initialCount = 1)
   {
      return new Semaphore(initialCount);
   }

   static void destroySemaphore(void * semaphore)
   {
      Semaphore* realSem = reinterpret_cast<Semaphore*>(semaphore);
      delete realSem;
   }

   static bool acquireSemaphore(void * semaphore, bool block = true)
   {
      Semaphore* realSem = reinterpret_cast<Semaphore*>(semaphore);
      return realSem->acquire(block);
   }

   static void releaseSemaphore(void * semaphore)
   {
      Semaphore* realSem = reinterpret_cast<Semaphore*>(semaphore);
      realSem->release();
   }
};

#endif