cmd/tip/hunt.c

	hunt.c revision 7c478bd95313f5f23a4c958a745db2134aa03244
/*
 * Copyright 2005 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */
/*
 * Copyright (c) 1983 Regents of the University of California.
 * All rights reserved. The Berkeley software License Agreement
 * specifies the terms and conditions for redistribution.
 */
#ident  "%Z%%M% %I% %E% SMI"    /* from UCB 4.7 6/25/83 */

#include "tip.h"

extern char *getremote();
extern int errno;

static  sigjmp_buf deadline;
static  int deadfl;

void
dead()
{

    deadfl = 1;
    siglongjmp(deadline, 1);
}

hunt(name)
    char *name;
{
    register char *cp;
    void (*f)();

    f = signal(SIGALRM, (sig_handler_t)dead);
    while (cp = getremote(name)) {
        deadfl = 0;
        uucplock = cp;
        if (mlock(uucplock) < 0) {
            delock(uucplock);
            continue;
        }
        /*
         * Straight through call units, such as the BIZCOMP,
         * VADIC and the DF, must indicate they're hardwired in
         *  order to get an open file descriptor placed in FD.
         * Otherwise, as for a DN-11, the open will have to
         *  be done in the "open" routine.
         */
        if (!HW)
            break;
        if (sigsetjmp(deadline, 1) == 0) {
            alarm(10);
            if (!trusted_device)
                userperm();
            errno = 0;
            if ((FD = open(cp, O_RDWR)) < 0 && errno != EBUSY) {
                fprintf(stderr, "tip: ");
                perror(cp);
            }
            if (!trusted_device)
                myperm();
            if (FD >= 0 && !isatty(FD)) {
                fprintf(stderr, "tip: %s: not a tty\n", cp);
                close(FD);
                FD = -1;
            }
        }
        alarm(0);
        if (!deadfl && FD >= 0) {
            struct termios t;

            ioctl(FD, TCGETS, &t);
            t.c_cflag |= XCLUDE|HUPCL;
            ioctl(FD, TCSETSF, &t);
            signal(SIGALRM, f);
            return ((int)cp);
        }
        delock(uucplock);
    }
    signal(SIGALRM, f);
    return (deadfl ? -1 : (int)cp);
}