/*      $OpenBSD: tipout.c,v 1.18 2006/05/31 07:03:08 jason Exp $       */
/*      $NetBSD: tipout.c,v 1.5 1996/12/29 10:34:12 cgd Exp $   */

/*-
 * SPDX-License-Identifier: BSD-3-Clause
 *
 * Copyright (c) 1983, 1993
 *      The Regents of the University of California.  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.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 REGENTS OR CONTRIBUTORS 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 "tip.h"

/*
 * tip
 *
 * lower fork of tip -- handles passive side
 *  reading from the remote host
 */

static  jmp_buf sigbuf;

static void     intIOT(int);
static void     intEMT(int);
static void     intTERM(int);
static void     intSYS(int);

/*
 * TIPOUT wait state routine --
 *   sent by TIPIN when it wants to posses the remote host
 */
/*ARGSUSED*/
static void
intIOT(int signo)
{
        write(repdes[1],&ccc,1);
        read(fildes[0], &ccc,1);
        longjmp(sigbuf, 1);
}

/*
 * Scripting command interpreter --
 *  accepts script file name over the pipe and acts accordingly
 */
/*ARGSUSED*/
static void
intEMT(int signo)
{
        char c, line[256];
        char *pline = line;
        char reply;

        read(fildes[0], &c, 1);
        while (c != '\n' && (size_t)(pline - line) < sizeof(line)) {
                *pline++ = c;
                read(fildes[0], &c, 1);
        }
        *pline = '\0';
        if (boolean(value(SCRIPT)) && fscript != NULL)
                fclose(fscript);
        if (pline == line) {
                setboolean(value(SCRIPT), FALSE);
                reply = 'y';
        } else {
                if ((fscript = fopen(line, "a")) == NULL)
                        reply = 'n';
                else {
                        reply = 'y';
                        setboolean(value(SCRIPT), TRUE);
                }
        }
        write(repdes[1], &reply, 1);
        longjmp(sigbuf, 1);
}

static void
intTERM(int signo)
{
        if (boolean(value(SCRIPT)) && fscript != NULL)
                fclose(fscript);
        if (signo && tipin_pid)
                kill(tipin_pid, signo);
        exit(0);
}

/*ARGSUSED*/
static void
intSYS(int signo)
{
        setboolean(value(BEAUTIFY), !boolean(value(BEAUTIFY)));
        longjmp(sigbuf, 1);
}

/*
 * ****TIPOUT   TIPOUT****
 */
void
tipout(void)
{
        char buf[BUFSIZ];
        char *cp;
        ssize_t scnt;
        size_t cnt;
        sigset_t mask, omask;

        signal(SIGINT, SIG_IGN);
        signal(SIGQUIT, SIG_IGN);
        signal(SIGEMT, intEMT);         /* attention from TIPIN */
        signal(SIGTERM, intTERM);       /* time to go signal */
        signal(SIGIOT, intIOT);         /* scripting going on signal */
        signal(SIGHUP, intTERM);        /* for dial-ups */
        signal(SIGSYS, intSYS);         /* beautify toggle */
        (void) setjmp(sigbuf);
        sigprocmask(SIG_BLOCK, NULL, &omask);
        for (;;) {
                sigprocmask(SIG_SETMASK, &omask, NULL);
                scnt = read(FD, buf, BUFSIZ);
                if (scnt <= 0) {
                        /* lost carrier */
                        if (scnt == 0 ||
                            (scnt < 0 && (errno == EIO || errno == ENXIO))) {
                                sigemptyset(&mask);
                                sigaddset(&mask, SIGTERM);
                                sigprocmask(SIG_BLOCK, &mask, NULL);
                                intTERM(SIGHUP);
                                /*NOTREACHED*/
                        }
                        continue;
                }
                cnt = scnt;
                sigemptyset(&mask);
                sigaddset(&mask, SIGEMT);
                sigaddset(&mask, SIGTERM);
                sigaddset(&mask, SIGIOT);
                sigaddset(&mask, SIGSYS);
                sigprocmask(SIG_BLOCK, &mask, NULL);
                for (cp = buf; cp < buf + cnt; cp++)
                        *cp &= STRIP_PAR;
                write(STDOUT_FILENO, buf, cnt);
                if (boolean(value(SCRIPT)) && fscript != NULL) {
                        if (!boolean(value(BEAUTIFY))) {
                                fwrite(buf, 1, cnt, fscript);
                        } else {
                                for (cp = buf; cp < buf + cnt; cp++)
                                        if ((*cp >= ' ' && *cp <= '~') ||
                                            any(*cp, value(EXCEPTIONS)))
                                                putc(*cp, fscript);
                        }
                        for (cp = buf; cp < buf + cnt; cp++) {
                                if (!isgraph(*cp)) {
                                        fflush(fscript);
                                        break;
                                }
                        }
                }
        }
}