poll.c

 
#include "types.h"
#include "defs.h"
#include "irx.h"
#include "stdio.h"
#include "sysclib.h"
#include "ps2ip.h"
 
#include "poll.h"
 
#define POLL_CAN_READ  (POLLIN | POLLRDNORM)
#define POLL_CAN_WRITE (POLLOUT | POLLWRNORM | POLLWRBAND)
#define POLL_HAS_EXCP  (POLLRDBAND | POLLPRI)
 
#define POLL_EVENTS_MASK (POLL_CAN_READ | POLL_CAN_WRITE | POLL_HAS_EXCP)
 
int poll(struct pollfd *fds, unsigned long nfds, int timeout)
{
    int i, err;
    fd_set rfd, wfd, efd, ifd;
    struct timeval timebuf;
    struct timeval *tbuf = (struct timeval *)0;
    int n                = 0;
    int count;
 
    FD_ZERO(&ifd);
    FD_ZERO(&rfd);
    FD_ZERO(&wfd);
    FD_ZERO(&efd);
 
    for (i = 0; (unsigned long)i < nfds; i++) {
        int events = fds[i].events;
        int fd     = fds[i].fd;
 
        fds[i].revents = 0;
 
        if ((fd < 0) || (FD_ISSET(fd, &ifd)))
            continue;
 
        if (fd > n)
            n = fd;
 
        if (events & POLL_CAN_READ)
            FD_SET(fd, &rfd);
 
        if (events & POLL_CAN_WRITE)
            FD_SET(fd, &wfd);
 
        if (events & POLL_HAS_EXCP)
            FD_SET(fd, &efd);
    }
 
    if (timeout >= 0) {
        timebuf.tv_sec  = timeout / 1000;
        timebuf.tv_usec = (timeout % 1000) * 1000;
        tbuf            = &timebuf;
    }
 
    err = lwip_select(n + 1, &rfd, &wfd, &efd, tbuf);
 
    if (err < 0)
        return err;
 
    count = 0;
 
    for (i = 0; (unsigned long)i < nfds; i++) {
        int revents = (fds[i].events & POLL_EVENTS_MASK);
        int fd      = fds[i].fd;
 
        if (fd < 0)
            continue;
 
        if (FD_ISSET(fd, &ifd))
            revents = POLLNVAL;
        else {
            if (!FD_ISSET(fd, &rfd))
                revents &= ~POLL_CAN_READ;
 
            if (!FD_ISSET(fd, &wfd))
                revents &= ~POLL_CAN_WRITE;
 
            if (!FD_ISSET(fd, &efd))
                revents &= ~POLL_HAS_EXCP;
        }
 
        if ((fds[i].revents = revents) != 0)
            count++;
    }
 
    return count;
}