countingsemaphore.cpp

Generic template class library for message queue implementation, uses pthread mutex.

#include "CountingSemaphore.h"
#include <cassert>

CountingSemaphore::CountingSemaphore(
    unsigned long value
)
{
  int sysCallResult;

  sysCallResult = sem_init( &posixSemaphore, 0, value );
  assert( sysCallResult != -1 );
}


CountingSemaphore::~CountingSemaphore()
{
  int sysCallResult;

  sysCallResult = sem_destroy( &posixSemaphore );
  assert( sysCallResult != -1 );
}

void CountingSemaphore::post()
{
  int sysCallResult;

  sysCallResult = sem_post( &posixSemaphore );
  assert( sysCallResult != -1 );
}

void CountingSemaphore::wait()
{
  int sysCallResult;

  sysCallResult = sem_wait( &posixSemaphore );
  assert( sysCallResult != -1 );
}

bool CountingSemaphore::trywait()
{
  int sysCallResult;
  bool returnValue;

  sysCallResult = sem_wait( &posixSemaphore );

  if ( sysCallResult == 0 )
    {
      returnValue = true;
    }
  else
    {
      returnValue = false;
    }

  return returnValue;
}