/*
 * 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. All advertising materials mentioning features or use of this software
 *    must display the following acknowledgement:
 *	This product includes software developed by the University of
 *	California, Berkeley and its contributors.
 * 4. 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.
 *
 * @(#) Copyright (c) 1983, 1993 The Regents of the University of California.  All rights reserved.
 * @(#)lpf.c	8.1 (Berkeley) 6/6/93
 * $FreeBSD: src/usr.sbin/lpr/filters/lpf.c,v 1.6.2.2 2001/10/13 19:01:45 gad Exp $
 * $DragonFly: src/usr.sbin/lpr/filters/lpf.c,v 1.3 2004/03/22 22:32:50 cpressey Exp $
 */

/*
 * 	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.
 *	further modified to let the compiler figure out which
 *	variables should be registers; they're very good at it these days.
 */

#include <signal.h>
#include <unistd.h>
#include <stdlib.h>
#include <stdio.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 */
char	*name;		/* user's login name */
char	*host;		/* user's machine name */
char	*acctfile;	/* accounting information file */

int
main(int argc, char **argv)
{
	FILE *p = stdin, *o = stdout;
	int i, col;
	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;
	}

	for (cp = buf[0], limit = buf[MAXREP]; cp < limit; *cp++ = ' ');
	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);
}