/*      $OpenBSD: lpf.c,v 1.13 2015/02/09 23:00:14 deraadt Exp $        */
/*      $NetBSD: lpf.c,v 1.8 2000/04/29 00:12:32 abs Exp $      */

/*
 * 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.
 */

/*
 *      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.
 */

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

#define MAXWIDTH  132
#define MAXREP    10

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

__dead void usage(void);

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

        while ((ch = getopt(argc, argv, "crh:i:j:l:n:w:")) != -1) {
                switch (ch) {
                case 'n':
                        name = optarg;
                        break;
                case 'h':
                        host = optarg;
                        break;
                case 'w':
                        if ((i = atoi(optarg)) > 0 && i <= MAXWIDTH)
                                width = i;
                        break;
                case 'l':
                        length = atoi(optarg);
                        break;
                case 'i':
                        indent = atoi(optarg);
                        break;
                case 'r':       /* map nl->cr-nl */
                        onlcr = 1;
                        break;
                case 'c':       /* Print control chars */
                        literal++;
                        break;
                case 'j':       /* ignore job name */
                        break;
                default:
                        usage();
                }
        }
        argc -= optind;
        argv += optind;
        if (argc)
                acctfile = *argv;

        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 {
                                if (onlcr)
                                        putc('\r', o);
                                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);
}

__dead void
usage(void)
{
        extern char *__progname;

        fprintf(stderr, "usage: %s [-c] [-r] [-h host] [-i indent] [-l length]"
            " [-n name] [-w width] [acctfile]\n", __progname);
        exit(1);
}