/*	$NetBSD: fpr.c,v 1.8 2008/07/21 14:19:22 lukem Exp $	*/

/*
 * Copyright (c) 1989, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Robert Corbett.
 *
 * 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 <sys/cdefs.h>
#ifndef lint
__COPYRIGHT("@(#) Copyright (c) 1989, 1993\
 The Regents of the University of California.  All rights reserved.");
#endif				/* not lint */

#ifndef lint
#if 0
static char sccsid[] = "@(#)fpr.c	8.1 (Berkeley) 6/6/93";
#endif
__RCSID("$NetBSD: fpr.c,v 1.8 2008/07/21 14:19:22 lukem Exp $");
#endif				/* not lint */

#include <err.h>
#include <stdio.h>
#include <stdlib.h>

#define BLANK ' '
#define TAB '\t'
#define NUL '\000'
#define FF '\f'
#define BS '\b'
#define CR '\r'
#define VTAB '\013'
#define EOL '\n'

#define TRUE 1
#define FALSE 0

#define MAXCOL 170
#define TABSIZE 8
#define INITWIDTH 8

typedef
struct column {
	int     count;
	int     width;
	char   *str;
}
        COLUMN;

char    cc;
char    saved;
int     length;
char   *text;
int     highcol;
COLUMN *line;
int     maxpos;
int     maxcol;

void	flush __P((void));
void	get_text __P((void));
void	init __P((void));
int	main __P((int, char **));
void	nospace __P((void));
void	savech __P((int));

int
main(argc, argv)
	int argc;
	char **argv;
{
	int ch;
	char ateof;
	int i;
	int errorcount;


	init();
	errorcount = 0;
	ateof = FALSE;

	ch = getchar();
	if (ch == EOF)
		exit(0);

	if (ch == EOL) {
		cc = NUL;
		ungetc((int) EOL, stdin);
	} else
		if (ch == BLANK)
			cc = NUL;
		else
			if (ch == '1')
				cc = FF;
			else
				if (ch == '0')
					cc = EOL;
				else
					if (ch == '+')
						cc = CR;
					else {
						errorcount = 1;
						cc = NUL;
						ungetc(ch, stdin);
					}

	while (!ateof) {
		get_text();
		ch = getchar();
		if (ch == EOF) {
			flush();
			ateof = TRUE;
		} else
			if (ch == EOL) {
				flush();
				cc = NUL;
				ungetc((int) EOL, stdin);
			} else
				if (ch == BLANK) {
					flush();
					cc = NUL;
				} else
					if (ch == '1') {
						flush();
						cc = FF;
					} else
						if (ch == '0') {
							flush();
							cc = EOL;
						} else
							if (ch == '+') {
								for (i = 0; i < length; i++)
									savech(i);
							} else {
								errorcount++;
								flush();
								cc = NUL;
								ungetc(ch, stdin);
							}
	}

	if (errorcount == 1)
		fprintf(stderr, "Illegal carriage control - 1 line.\n");
	else
		if (errorcount > 1)
			fprintf(stderr, "Illegal carriage control - %d lines.\n", errorcount);

	exit(0);
}

void
init()
{
	COLUMN *cp;
	COLUMN *cend;
	char *sp;


	length = 0;
	maxpos = MAXCOL;
	sp = malloc((unsigned) maxpos);
	if (sp == NULL)
		nospace();
	text = sp;

	highcol = -1;
	maxcol = MAXCOL;
	line = (COLUMN *) calloc(maxcol, (unsigned) sizeof(COLUMN));
	if (line == NULL)
		nospace();
	cp = line;
	cend = line + (maxcol - 1);
	while (cp <= cend) {
		cp->width = INITWIDTH;
		sp = calloc(INITWIDTH, (unsigned) sizeof(char));
		if (sp == NULL)
			nospace();
		cp->str = sp;
		cp++;
	}
}

void
get_text()
{
	int i;
	char ateol;
	int ch;
	int pos;
	char *n;

	i = 0;
	ateol = FALSE;

	while (!ateol) {
		ch = getchar();
		if (ch == EOL || ch == EOF)
			ateol = TRUE;
		else
			if (ch == TAB) {
				pos = (1 + i / TABSIZE) * TABSIZE;
				if (pos > maxpos) {
					n = realloc(text, (unsigned)(pos + 10));
					if (n == NULL)
						nospace();
					text = n;
					maxpos = pos + 10;
				}
				while (i < pos) {
					text[i] = BLANK;
					i++;
				}
			} else
				if (ch == BS) {
					if (i > 0) {
						i--;
						savech(i);
					}
				} else
					if (ch == CR) {
						while (i > 0) {
							i--;
							savech(i);
						}
					} else
						if (ch == FF || ch == VTAB) {
							flush();
							cc = ch;
							i = 0;
						} else {
							if (i >= maxpos) {
								n = realloc(text, (unsigned)(i + 10));
								if (n == NULL)
									nospace();
								maxpos = i + 10;
							}
							text[i] = ch;
							i++;
						}
	}

	length = i;
}

void
savech(col)
	int     col;
{
	char ch;
	int oldmax;
	COLUMN *cp;
	COLUMN *cend;
	char *sp;
	int newcount;
	COLUMN *newline;

	ch = text[col];
	if (ch == BLANK)
		return;

	saved = TRUE;

	if (col >= highcol)
		highcol = col;

	if (col >= maxcol) {
		newline = (COLUMN *) realloc(line,
		    (unsigned) (col + 10) * sizeof(COLUMN));
		if (newline == NULL)
			nospace();
		line = newline;
		oldmax = maxcol;
		maxcol = col + 10;
		cp = line + oldmax;
		cend = line + (maxcol - 1);
		while (cp <= cend) {
			cp->width = INITWIDTH;
			cp->count = 0;
			sp = calloc(INITWIDTH, (unsigned) sizeof(char));
			if (sp == NULL)
				nospace();
			cp->str = sp;
			cp++;
		}
	}
	cp = line + col;
	newcount = cp->count + 1;
	if (newcount > cp->width) {
		cp->width = newcount;
		sp = realloc(cp->str, (unsigned) newcount * sizeof(char));
		if (sp == NULL)
			nospace();
		cp->str = sp;
	}
	cp->count = newcount;
	cp->str[newcount - 1] = ch;
}

void
flush()
{
	int i;
	int anchor;
	int height;
	int j;

	if (cc != NUL)
		putchar(cc);

	if (!saved) {
		i = length;
		while (i > 0 && text[i - 1] == BLANK)
			i--;
		length = i;
		for (i = 0; i < length; i++)
			putchar(text[i]);
		putchar(EOL);
		return;
	}
	for (i = 0; i < length; i++)
		savech(i);

	anchor = 0;
	while (anchor <= highcol) {
		height = line[anchor].count;
		if (height == 0) {
			putchar(BLANK);
			anchor++;
		} else
			if (height == 1) {
				putchar(*(line[anchor].str));
				line[anchor].count = 0;
				anchor++;
			} else {
				i = anchor;
				while (i < highcol && line[i + 1].count > 1)
					i++;
				for (j = anchor; j <= i; j++) {
					height = line[j].count - 1;
					putchar(line[j].str[height]);
					line[j].count = height;
				}
				for (j = anchor; j <= i; j++)
					putchar(BS);
			}
	}

	putchar(EOL);
	highcol = -1;
}

void
nospace()
{
	errx(1, "Storage limit exceeded.");
}