Semaphore.hpp

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#ifndef BLOCXX_SEMAPHORE_HPP_INCLUDE_GUARD_
#define BLOCXX_SEMAPHORE_HPP_INCLUDE_GUARD_
#include "blocxx/BLOCXX_config.h"
#include "blocxx/Types.hpp"
#include "blocxx/NonRecursiveMutex.hpp"
#include "blocxx/Condition.hpp"
#include "blocxx/NonRecursiveMutexLock.hpp"
#include "blocxx/Timeout.hpp"
#include "blocxx/TimeoutTimer.hpp"
 
namespace BLOCXX_NAMESPACE
{
// TODO: uninline this class.
class Semaphore
{
public:
   Semaphore()
      : m_curCount(0)
   {}
   Semaphore(Int32 initCount)
      : m_curCount(initCount)
   {}
   void wait()
   {
      NonRecursiveMutexLock l(m_mutex);
      while (m_curCount <= 0)
      {
         m_cond.wait(l);
      }
      --m_curCount;
   }
   BLOCXX_DEPRECATED bool timedWait(UInt32 sTimeout, UInt32 usTimeout=0) // in 4.0.0
   {
      return timedWait(Timeout::relative(sTimeout + static_cast<float>(usTimeout) * 1000000.0));
   }
   bool timedWait(const Timeout& timeout)
   {
      bool ret = true;
      NonRecursiveMutexLock l(m_mutex);
      TimeoutTimer timer(timeout);
      while (m_curCount <= 0 && ret == true)
      {
         ret = m_cond.timedWait(l, timer.asAbsoluteTimeout());
      }
      if (ret == true)
      {
         --m_curCount;
      }
      return ret;
   }
   void signal()
   {
      NonRecursiveMutexLock l(m_mutex);
      ++m_curCount;
      m_cond.notifyAll();
   }
   Int32 getCount()
   {
      NonRecursiveMutexLock l(m_mutex);
      return m_curCount;
   }
private:
   Int32 m_curCount;
   Condition m_cond;
   NonRecursiveMutex m_mutex;
   // noncopyable
   Semaphore(const Semaphore&);
   Semaphore& operator=(const Semaphore&);
};
 
} // end namespace BLOCXX_NAMESPACE
 
#endif