/* Program: test_timeout.c */

#include <stdio.h>
#include <signal.h>
#include <string.h>
#include <errno.h>
#include <fcntl.h>
#include <time.h> /* timespec definition */
#include <poll.h>
#include <sys/select.h>
#include <sys/time.h> /* timespec definition */
#include <unistd.h>

int main(void)
{
  printf("\nPoll test\n");
  /* Data structure describing a polling request.  */
  //struct pollfd
  //{
  //  int fd;                     /* File descriptor to poll.  */
  //  short int events;           /* Types of events poller cares about.  */
  //  short int revents;          /* Types of events that actually occurred.  */
  //};

  int nfound = -1, nfds = -1;
  int timeout_msecs = 0;
  struct pollfd fds[1];

  nfound = -1;
  nfds = 1;
  fds[0].fd = 0;
  fds[0].events = POLLIN | POLLRDNORM | POLLOUT | POLLRDBAND;
  fds[0].revents = 0;
  timeout_msecs = 0;
  fprintf(stderr,"\nTest 1: timeout_msec=%d\n", timeout_msecs);
  printf("Input: nfound=%d, fds[0].{fd,events,revents}={%d,%d,%d}\n", nfound, fds[0].fd, fds[0].events, fds[0].revents);
  nfound = poll(fds, nfds, timeout_msecs);
  printf("Output: nfound=%d, fds[0].{fd,events,revents}={%d,%d,%d}\n", nfound, fds[0].fd, fds[0].events, fds[0].revents);

  nfound = -1;
  nfds = 1;
  fds[0].fd = 0;
  fds[0].events =  POLLIN | POLLRDNORM | POLLOUT | POLLRDBAND;
  fds[0].revents = 0;
  timeout_msecs = 1;
  fprintf(stderr,"\nTest 2: timeout_msec=%d\n", timeout_msecs);
  printf("Input: nfound=%d, fds[0].{fd,events,revents}={%d,%d,%d}\n", nfound, fds[0].fd, fds[0].events, fds[0].revents);
  nfound = poll(fds, nfds, timeout_msecs);
  printf("Output: nfound=%d, fds[0].{fd,events,revents}={%d,%d,%d}\n", nfound, fds[0].fd, fds[0].events, fds[0].revents);

  printf("\nSelect test\n");

// typedef struct
//  {
//  __fd_mask __fds_bits[__FD_SETSIZE / __NFDBITS];
// # define __FDS_BITS(set) ((set)->__fds_bits)
//  } fd_set;

// struct timeval {
//  __time_t tv_sec;            /* Seconds.  */
//  __suseconds_t tv_usec;      /* Microseconds.  */
// };

/* Code inspired by: http://bugs.debian.org/79358*/

  fd_set rfds;
  struct timeval timeout_usecs = {0,0};

  nfound = -1;
  nfds = 1;
  FD_ZERO(&rfds);
  FD_SET(0, &rfds);
  timeout_usecs.tv_sec = 0;
  timeout_usecs.tv_usec = 0;
  fprintf(stderr,"\nTest 1: timeout_usecs=(%ld,%ld)\n", timeout_usecs.tv_sec,timeout_usecs.tv_usec);
  printf ("Press Enter ");
  fflush(stdout);
  sleep(3);
  nfound = select(nfds, &rfds, NULL, NULL, &timeout_usecs);
  printf("Output: nfound=%d\n",nfound);

  nfound = -1;
  nfds = 1;
  FD_ZERO(&rfds);
  FD_SET(0, &rfds);
  timeout_usecs.tv_sec = 0;
  timeout_usecs.tv_usec = 1;
  fprintf(stderr,"\nTest 2: timeout_usecs=(%ld,%ld)\n", timeout_usecs.tv_sec,timeout_usecs.tv_usec);
  printf("Input: nfound=%d\n", nfound);
  printf ("Press Enter ");
  fflush(stdout);
  sleep(3);
  nfound = select(nfds, &rfds, NULL, NULL, &timeout_usecs);
  printf("Output: nfound=%d\n",nfound);


  return 0;
}