trequest.cpp

// #################################################################################################
//  ALib C++ Library
//
//  Copyright 2013-2019 A-Worx GmbH, Germany
//  Published under 'Boost Software License' (a free software license, see LICENSE.txt)
// #################################################################################################
 
#if !defined(HPP_AWORX_ALIB_THREADS_MODEL_THREADMANAGER)
#   include "alib/threads/model/trequest.hpp"
#endif
 
#if !defined(ALIB_DOX)  // todo remove
 
namespace alib::threads::model {
 
TRequest::TRequest(void *pData)
{
    // save parameters
    this->data=     pData;
    data2     =  nullptr;
    status    =     0;
 
    // initialize semaphore, it is local and has count 0 (wake up condition is > 0)
    sem_init(&event, 0, 0);
}
 
TRequest::~TRequest()
{
    waitUntilProcessed();
 
    if (sem_destroy(&event)==-1 && errno==EBUSY)
    ALIB_MESSAGE("ATHR", "Can't destroy semaphore")
}
 
void TRequest::setProcessed()
{
    // set processed: semaphore is increased
    sem_post(&event);
}
 
bool TRequest::isProcessed()
{
    int retVal;
 
    // read count from the semaphore
    lock.Acquire(ALIB_CALLER_PRUNED);
        sem_getvalue(&event, &retVal);
    lock.Release();
 
    return (retVal != 0);
}
 
bool TRequest::waitUntilProcessed(int millisecs)
{
    bool    retval;
 
    lock.Acquire(ALIB_CALLER_PRUNED);
        if (millisecs >= 0)
        {
            // calc breaktime
            Ticks breakTime;
            breakTime+= Ticks::Duration::FromAbsoluteMilliseconds( millisecs );
 
            // wait until timeout
            retval= true;
            while (sem_trywait(&event) == -1 && errno == EAGAIN)
            {
                Ticks now;
                if( breakTime > now )
                    Thread::SleepMicros( (breakTime - now).InAbsoluteMicroseconds() );
                else
                {
                    retval= false;
                    break;
                }
            }
        }
        else
        {
            // wait for an unlimited time (millisecs < 0)
            // until semaphore is increased to > 0
            sem_wait(&event);
            retval= true;
        }
 
        // set semaphore to signaled again
        // to maintain the signal for other waiters or for
        // deletion
        sem_post(&event);
    lock.Release();
 
    return retval;
}
 
 
} // namespace [alib::threads::model]
 
#endif // !defined(ALIB_DOX)