lix/src/libutil/monitor-fd.hh
2014-07-24 01:21:56 +02:00

51 lines
1 KiB
C++

#pragma once
#include <thread>
#include <atomic>
#include <poll.h>
#include <sys/types.h>
#include <unistd.h>
#include <signal.h>
namespace nix {
class MonitorFdHup
{
private:
std::thread thread;
std::atomic_bool quit;
public:
MonitorFdHup(int fd)
{
quit = false;
thread = std::thread([&]() {
/* Wait indefinitely until a POLLHUP occurs. */
struct pollfd fds[1];
fds[0].fd = fd;
fds[0].events = 0;
if (poll(fds, 1, -1) == -1) {
if (errno != EINTR) abort(); // can't happen
assert(quit);
return; // destructor is asking us to exit
}
fprintf(stderr, "GOT: %d\n", fds[0].revents);
assert(fds[0].revents & POLLHUP);
/* We got POLLHUP, so send an INT signal to the main thread. */
kill(getpid(), SIGINT);
});
};
~MonitorFdHup()
{
quit = true;
pthread_kill(thread.native_handle(), SIGINT);
thread.join();
}
};
}