/* This work is copyrighted. See COPYRIGHT.OLD & COPYRIGHT.NEW for   *
*  details. If they are missing then this copy is in violation of    *
*  the copyright conditions.                                        */

/*
**	lib_twait.c
**
**	The routine timed_wait().
**
*/

#include <string.h>
#include <sys/time.h>
#include <unistd.h>
#include "curses.priv.h"

int timed_wait(int fd, int wait, int *timeleft)
{
int result;
struct timeval timeout;
static fd_set set;
#ifndef GOOD_SELECT
struct timeval starttime, returntime;

    gettimeofday(&starttime, NULL);
#endif

    FD_ZERO(&set);
    FD_SET(fd, &set);

    /* the units of wait are milliseconds */
    timeout.tv_sec = wait / 1000;
    timeout.tv_usec = (wait % 1000) * 1000;

    T(("start twait: sec = %d, usec = %d", timeout.tv_sec, timeout.tv_usec));

    result = select(fd+1, &set, NULL, NULL, &timeout);

#ifndef GOOD_SELECT
    gettimeofday(&returntime, NULL);
    timeout.tv_sec -= (returntime.tv_sec - starttime.tv_sec);
    timeout.tv_usec -= (returntime.tv_usec - starttime.tv_usec);
    if (timeout.tv_usec < 0 && timeout.tv_sec > 0) {
		timeout.tv_sec--;
		timeout.tv_usec += 1000000;
    }
    if (timeout.tv_sec < 0)
		timeout.tv_sec = timeout.tv_usec = 0;
#endif

    /* return approximate time left on the timeout, in milliseconds */
    if (timeleft)
		*timeleft = (timeout.tv_sec * 1000) + (timeout.tv_usec / 1000);

    T(("end twait: returned %d, sec = %d, usec = %d (%d msec)",
	    result, timeout.tv_sec, timeout.tv_usec, *timeleft));

    return(result);
}