root/usr.sbin/mopd/common/loop-linux2.c
/*      $NetBSD: loop-linux2.c,v 1.3 2020/04/22 23:55:29 joerg Exp $    */

/*
 * Copyright (c) 1993-95 Mats O Jansson.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "port.h"
#ifndef lint
__RCSID("$NetBSD: loop-linux2.c,v 1.3 2020/04/22 23:55:29 joerg Exp $");
#endif

#include <stdlib.h>
#include <strings.h>
#include <unistd.h>
#include <errno.h>
#if defined(__bsdi__) || defined(__FreeBSD__)
#include <sys/time.h>
#endif
#include <sys/ioctl.h>

#include "os.h"
#include "common.h"
#include "mopdef.h"

int
mopOpenRC(struct if_info *p, int trans)
{
#ifndef NORC
        return (*(p->iopen))(p->if_name,
                             O_RDWR,
                             MOP_K_PROTO_RC,
                             trans);
#else
        return -1;
#endif
}

int
mopOpenDL(struct if_info *p, int trans)
{
#ifndef NODL
        return (*(p->iopen))(p->if_name,
                             O_RDWR,
                             MOP_K_PROTO_DL,
                             trans);
#else
        return -1;
#endif
}

void
mopReadRC(void)
{
}

void
mopReadDL(void)
{
}

/*
 * The list of all interfaces that are being listened to.  loop()
 * "selects" on the descriptors in this list.
 */
extern struct if_info *iflist;

void   mopProcess(struct if_info *, u_char *);

/*
 * Loop indefinitely listening for MOP requests on the
 * interfaces in 'iflist'.
 */
void
Loop(void)
{
        u_char *buf, *bp, *ep;
        int     cc;
        fd_set  fds, listeners;
        int     bufsize = 1100, maxfd =0;
        struct if_info *ii;


        if (iflist == 0) {
                syslog(LOG_ERR, "no interfaces");
                exit(0);
        }

         buf = (u_char *) malloc((unsigned) bufsize); 

        if (buf == 0) {
                syslog(LOG_ERR, "malloc: %m");
                exit(0);
        }
        /*
         * Find the highest numbered file descriptor for select().
         * Initialize the set of descriptors to listen to.
         */
        FD_ZERO(&fds);
        for (ii = iflist; ii; ii = ii->next) {
                if (ii->fd != -1) {
                        FD_SET(ii->fd, &fds);
                        if (ii->fd > maxfd)
                                maxfd = ii->fd;
                }
        }
        while (1) {
                listeners = fds;
                if (select(maxfd + 1, &listeners, (fd_set *) 0,
                        (fd_set *) 0, (struct timeval *) 0) < 0) {
                        syslog(LOG_ERR, "select: %m");
                        exit(0);
                }
                for (ii = iflist; ii; ii = ii->next) {
                        if (ii->fd != -1) {
                                if (!FD_ISSET(ii->fd, &listeners))
                                        continue;
                        }
        again:
                        cc = read(ii->fd, (char *) buf, bufsize);
                        /* Don't choke when we get ptraced */
                        if (cc < 0 && errno == EINTR)
                                goto again;

                        bp = buf;
                        ep = bp + cc;
        
                        if(bp < ep) {
                                mopProcess(ii,buf);
                        }

                }
        }               
}