DAQ++ git-daqpp

#include <iostream>
#include <cstdio>
#include "Trigger.h"


Trigger::Trigger(double f)
    : fd(-1), freq(f), fname("/tmp/trigger.dat"), running(false)
{
    if (! access(fname.c_str(), F_OK) )
        unlink(fname.c_str());


    if ( mkfifo(fname.c_str(), 0660) )
    {
        perror("Could not create the fifo:\n\t");
        return;
    }
    fd = open(fname.c_str(), O_RDWR);

    if (freq <= 0)
        freq = 50.;

    set_freq(freq);
}
Trigger::~Trigger()
{
    if (fd >= 0)
    {
        close(fd);
        unlink(fname.c_str());
    }
}
void Trigger::run()
{
    char val = 'A';
    running = true;
    while (running)
    {
        loop();
        write(fd, &val, sizeof(char));
        test_cancel();
    }
}

void Trigger::loop()
{
//    volatile unsigned long iloop;
//    for (iloop = 0;iloop < nloop;iloop++);
    DAQpp::wait(period);
}

void Trigger::set_freq(double x)
{
    DAQpp::GTimer timer;
    if (x > 0.)
    {
        freq = x;
        period = 1./freq;
    }
//    nloop = 100000000;
//    timer.start();
//    loop();
//    timer.stop();
//    nloop = (unsigned long)(((double)nloop) / timer() / freq);
//    std::cout << "nloop " << nloop << std::endl;
}

/*
  Function to enable and disable the external trigger, and the trigger
  function.
 */
bool Trigger::operator()()
{
    int rc=0;
    char val;
    if ( fdlist.fd < 0 )
        return false;

    while (rc == 0)
    {
        // we poll with a timeout to avoid hang ups
        rc = poll(&fdlist, 1, 100);
        if ( ! DAQpp::DAQmanager::theDAQmanager()->isRunning() )
            break;
        if (rc == 0)
            continue;
        if (rc > 0)
        {
            if ( fdlist.revents & (POLLNVAL | POLLERR | POLLHUP | POLLERR) )
                return false;
            if ( fdlist.revents & (POLLIN | POLLPRI) )
            {
                read(fdlist.fd, &val, sizeof(char));
                return true;
            }
        }
        else
        {
            std::cout << "InterruptTrigger: something happened" << std::endl;
        }
    }
    return false;
}

void Trigger::enableInterrupts()
{
    fdlist.fd = open(get_file_name().c_str(), O_RDONLY);
    fdlist.events = POLLIN | POLLPRI;

    // Make DAQmanager aware of this
    DAQpp::DAQmanager::theDAQmanager()->set_trigger(this);

    // start the thread that generates the data
    start();

    return;
}

void Trigger::disableInterrupts()
{
    DAQpp::DAQmanager::theDAQmanager()->set_trigger(0);

    running = false;
    DAQpp::wait(0.001);
    if (is_running())
        stop();

    if ( fdlist.fd >= 0 )
        close(fdlist.fd);

    fdlist.fd = -1;


    return;
}