/*-
 * 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 "lp.cdefs.h"           /* A cross-platform version of <sys/cdefs.h> */
/*
 *      filter which reads the output of nroff and converts lines
 *      with ^H's to overwritten lines.  Thus this works like 'ul'
 *      but is much better: it can handle more than 2 overwrites
 *      and it is written with some style.
 *      modified by kls to use register references instead of arrays
 *      to try to gain a little speed.
 */

#include <signal.h>
#include <unistd.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>

#define MAXWIDTH  132
#define MAXREP    10

static char     buf[MAXREP][MAXWIDTH];
static int      maxcol[MAXREP] = {-1};
static int      lineno;
static int      width = 132;    /* default line length */
static int      length = 66;    /* page length */
static int      indent;         /* indentation length */
static int      npages = 1;
static int      literal;        /* print control characters */
static char     *name;          /* user's login name */
static char     *host;          /* user's machine name */
static char     *acctfile;      /* accounting information file */

int
main(int argc, char *argv[])
{
        register FILE *p = stdin, *o = stdout;
        register int i, col;
        register char *cp;
        int done, linedone, maxrep;
        char *limit;
        int ch;

        while (--argc) {
                if (*(cp = *++argv) == '-') {
                        switch (cp[1]) {
                        case 'n':
                                argc--;
                                name = *++argv;
                                break;

                        case 'h':
                                argc--;
                                host = *++argv;
                                break;

                        case 'w':
                                if ((i = atoi(&cp[2])) > 0 && i <= MAXWIDTH)
                                        width = i;
                                break;

                        case 'l':
                                length = atoi(&cp[2]);
                                break;

                        case 'i':
                                indent = atoi(&cp[2]);
                                break;

                        case 'c':       /* Print control chars */
                                literal++;
                                break;
                        }
                } else
                        acctfile = cp;
        }

        memset(buf, ' ', sizeof(buf));
        done = 0;

        while (!done) {
                col = indent;
                maxrep = -1;
                linedone = 0;
                while (!linedone) {
                        switch (ch = getc(p)) {
                        case EOF:
                                linedone = done = 1;
                                ch = '\n';
                                break;

                        case '\f':
                                lineno = length;
                        case '\n':
                                if (maxrep < 0)
                                        maxrep = 0;
                                linedone = 1;
                                break;

                        case '\b':
                                if (--col < indent)
                                        col = indent;
                                break;

                        case '\r':
                                col = indent;
                                break;

                        case '\t':
                                col = ((col - indent) | 07) + indent + 1;
                                break;

                        case '\031':
                                /*
                                 * lpd needs to use a different filter to
                                 * print data so stop what we are doing and
                                 * wait for lpd to restart us.
                                 */
                                if ((ch = getchar()) == '\1') {
                                        fflush(stdout);
                                        kill(getpid(), SIGSTOP);
                                        break;
                                } else {
                                        ungetc(ch, stdin);
                                        ch = '\031';
                                }

                        default:
                                if (col >= width || (!literal && ch < ' ')) {
                                        col++;
                                        break;
                                }
                                cp = &buf[0][col];
                                for (i = 0; i < MAXREP; i++) {
                                        if (i > maxrep)
                                                maxrep = i;
                                        if (*cp == ' ') {
                                                *cp = ch;
                                                if (col > maxcol[i])
                                                        maxcol[i] = col;
                                                break;
                                        }
                                        cp += MAXWIDTH;
                                }
                                col++;
                                break;
                        }
                }

                /* print out lines */
                for (i = 0; i <= maxrep; i++) {
                        for (cp = buf[i], limit = cp+maxcol[i]; cp <= limit;) {
                                putc(*cp, o);
                                *cp++ = ' ';
                        }
                        if (i < maxrep)
                                putc('\r', o);
                        else
                                putc(ch, o);
                        if (++lineno >= length) {
                                fflush(o);
                                npages++;
                                lineno = 0;
                        }
                        maxcol[i] = -1;
                }
        }
        if (lineno) {           /* be sure to end on a page boundary */
                putchar('\f');
                npages++;
        }
        if (name && acctfile && access(acctfile, 02) >= 0 &&
            freopen(acctfile, "a", stdout) != NULL) {
                printf("%7.2f\t%s:%s\n", (float)npages, host, name);
        }
        exit(0);
}