Poller.cc

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#include "Poller.hh"

#ifndef _WIN32
#include <cstdio>
#include <poll.h>
#include <unistd.h>
#endif


namespace openmsx {

Poller::Poller()
        : abortFlag(false)
{
#ifndef _WIN32
        if (pipe(wakeupPipe)) {
                wakeupPipe[0] = wakeupPipe[1] = -1;
                perror("Failed to open wakeup pipe");
        }
#endif
}

Poller::~Poller()
{
#ifndef _WIN32
        close(wakeupPipe[0]);
        close(wakeupPipe[1]);
#endif
}

void Poller::abort()
{
        abortFlag = true;
#ifndef _WIN32
        char dummy = 'X';
        if (write(wakeupPipe[1], &dummy, sizeof(dummy)) == -1) {
                // Nothing we can do here; we'll have to rely on the poll() timeout.
        }
#endif
}

#ifndef _WIN32
bool Poller::poll(int fd)
{
        while (true) {
                struct pollfd fds[2] = {
                        { .fd = fd, .events = POLLIN, .revents = 0 },
                        { .fd = wakeupPipe[0], .events = POLLIN, .revents = 0 },
                };
                int pollResult = ::poll(fds, 2, 1000);
                if (abortFlag) {
                        return true;
                }
                if (pollResult == -1) { // error
                        return true;
                }
                if (pollResult != 0) { // no timeout
                        return false;
                }
        }
}
#endif

} // namespace openmsx