Add function to fake a poll call using select

/*

 * fakepoll.c

 *

 * On systems where 'poll' doesn't exist, fake it with 'select'.

 *

 * Nick Mathewson <nickm@freehaven.net>

 */

/*

 * Changes :

 * $Log$

 * Revision 1.1  2002/09/03 18:43:50  nickm

 * Add function to fake a poll call using select

 *

 */

#include "fakepoll.h"

#ifdef USE_FAKE_POLL

#include <sys/time.h>

#include <sys/types.h>

#include <unistd.h>

#include <string.h>

int

poll(struct pollfd *ufds, unsigned int nfds, int timeout)

{

	int idx, maxfd, fd, r;

	fd_set readfds, writefds, exceptfds;

	struct timeval _timeout;

	_timeout.tv_sec = timeout/1000;

	_timeout.tv_usec = (timeout%1000)*1000;

	FD_ZERO(&readfds);

	FD_ZERO(&writefds);

	FD_ZERO(&exceptfds);

	maxfd = -1;

	for (idx = 0; idx < nfds; ++idx) {

		fd = ufds[idx].fd;

		if (fd > maxfd && ufds[idx].events)

			maxfd = fd;

		if (ufds[idx].events & (POLLIN))

			FD_SET(fd, &readfds);

		if (ufds[idx].events & POLLOUT)

			FD_SET(fd, &writefds);

		if (ufds[idx].events & (POLLERR))

			FD_SET(fd, &exceptfds);

	}

	r = select(maxfd+1, &readfds, &writefds, &exceptfds, 

		   timeout == -1 ? NULL : &_timeout);

	if (r <= 0)

		return r;

	r = 0;

	for (idx = 0; idx < nfds; ++idx) {

		fd = ufds[idx].fd;

		ufds[idx].revents = 0;

		if (FD_ISSET(fd, &readfds))

			ufds[idx].revents |= POLLIN;

		if (FD_ISSET(fd, &writefds))

			ufds[idx].revents |= POLLOUT;

		if (FD_ISSET(fd, &exceptfds))

			ufds[idx].revents |= POLLERR;

		if (ufds[idx].revents)

			++r;

	}

	return r;

}

#endif

/*

 * fakepoll.h

 *

 * On systems where 'poll' doesn't exist, fake it with 'select'.

 *

 * Nick Mathewson <nickm@freehaven.net>

 */

/*

 * Changes :

 * $Log$

 * Revision 1.1  2002/09/03 18:43:50  nickm

 * Add function to fake a poll call using select

 *

 */

#ifndef __FAKEPOLL_H

#define __FAKEPOLL_H

#include "orconfig.h"

#undef VERSION

#ifndef HAVE_POLL_H

#ifndef HAVE_SYS_POLL_H

#define USE_FAKE_POLL

struct pollfd {

	int fd;

	short events;

	short revents;

};

#define POLLIN   0x0001

#define POLLPRI  0x0002

#define POLLOUT  0x0004

#define POLLERR  0x0008

#define POLLHUP  0x0010

#define POLLNVAL 0x0020

int poll(struct pollfd *ufds, unsigned int nfds, int timeout);

#endif

#endif

#endif