col.c revision 87628 
1/*-
2 * Copyright (c) 1990, 1993, 1994
3 *	The Regents of the University of California.  All rights reserved.
4 *
5 * This code is derived from software contributed to Berkeley by
6 * Michael Rendell of the Memorial University of Newfoundland.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 * 3. All advertising materials mentioning features or use of this software
17 *    must display the following acknowledgement:
18 *	This product includes software developed by the University of
19 *	California, Berkeley and its contributors.
20 * 4. Neither the name of the University nor the names of its contributors
21 *    may be used to endorse or promote products derived from this software
22 *    without specific prior written permission.
23 *
24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34 * SUCH DAMAGE.
35 */
36
37#ifndef lint
38static const char copyright[] =
39"@(#) Copyright (c) 1990, 1993, 1994\n\
40	The Regents of the University of California.  All rights reserved.\n";
41#endif
42
43#if 0
44#ifndef lint
45static char sccsid[] = "@(#)col.c	8.5 (Berkeley) 5/4/95";
46#endif
47#endif
48
49#include <sys/cdefs.h>
50__FBSDID("$FreeBSD: head/usr.bin/col/col.c 87628 2001-12-10 21:13:08Z dwmalone $");
51
52#include <ctype.h>
53#include <err.h>
54#include <string.h>
55#include <stdio.h>
56#include <stdlib.h>
57#include <unistd.h>
58#include <locale.h>
59
60#define	BS	'\b'		/* backspace */
61#define	TAB	'\t'		/* tab */
62#define	SPACE	' '		/* space */
63#define	NL	'\n'		/* newline */
64#define	CR	'\r'		/* carriage return */
65#define	ESC	'\033'		/* escape */
66#define	SI	'\017'		/* shift in to normal character set */
67#define	SO	'\016'		/* shift out to alternate character set */
68#define	VT	'\013'		/* vertical tab (aka reverse line feed) */
69#define	RLF	'\007'		/* ESC-07 reverse line feed */
70#define	RHLF	'\010'		/* ESC-010 reverse half-line feed */
71#define	FHLF	'\011'		/* ESC-011 forward half-line feed */
72
73/* build up at least this many lines before flushing them out */
74#define	BUFFER_MARGIN		32
75
76typedef char CSET;
77
78typedef struct char_str {
79#define	CS_NORMAL	1
80#define	CS_ALTERNATE	2
81	short		c_column;	/* column character is in */
82	CSET		c_set;		/* character set (currently only 2) */
83	char		c_char;		/* character in question */
84} CHAR;
85
86typedef struct line_str LINE;
87struct line_str {
88	CHAR	*l_line;		/* characters on the line */
89	LINE	*l_prev;		/* previous line */
90	LINE	*l_next;		/* next line */
91	int	l_lsize;		/* allocated sizeof l_line */
92	int	l_line_len;		/* strlen(l_line) */
93	int	l_needs_sort;		/* set if chars went in out of order */
94	int	l_max_col;		/* max column in the line */
95};
96
97LINE   *alloc_line __P((void));
98void	dowarn __P((int));
99void	flush_line __P((LINE *));
100void	flush_lines __P((int));
101void	flush_blanks __P((void));
102void	free_line __P((LINE *));
103int	main __P((int, char **));
104void	usage __P((void));
105
106CSET	last_set;		/* char_set of last char printed */
107LINE   *lines;
108int	compress_spaces;	/* if doing space -> tab conversion */
109int	fine;			/* if `fine' resolution (half lines) */
110int	max_bufd_lines;		/* max # lines to keep in memory */
111int	nblank_lines;		/* # blanks after last flushed line */
112int	no_backspaces;		/* if not to output any backspaces */
113int	pass_unknown_seqs;	/* pass unknown control sequences */
114
115#define	PUTC(ch) \
116	do {					\
117		if (putchar(ch) == EOF)		\
118			errx(1, "write error");	\
119	} while (0)
120
121int
122main(argc, argv)
123	int argc;
124	char **argv;
125{
126	int ch;
127	CHAR *c;
128	CSET cur_set;			/* current character set */
129	LINE *l;			/* current line */
130	int extra_lines;		/* # of lines above first line */
131	int cur_col;			/* current column */
132	int cur_line;			/* line number of current position */
133	int max_line;			/* max value of cur_line */
134	int this_line;			/* line l points to */
135	int nflushd_lines;		/* number of lines that were flushed */
136	int adjust, opt, warned;
137
138	(void)setlocale(LC_CTYPE, "");
139
140	max_bufd_lines = 128;
141	compress_spaces = 1;		/* compress spaces into tabs */
142	while ((opt = getopt(argc, argv, "bfhl:px")) != -1)
143		switch (opt) {
144		case 'b':		/* do not output backspaces */
145			no_backspaces = 1;
146			break;
147		case 'f':		/* allow half forward line feeds */
148			fine = 1;
149			break;
150		case 'h':		/* compress spaces into tabs */
151			compress_spaces = 1;
152			break;
153		case 'l':		/* buffered line count */
154			if ((max_bufd_lines = atoi(optarg)) <= 0)
155				errx(1, "bad -l argument %s", optarg);
156			break;
157		case 'p':		/* pass unknown control sequences */
158			pass_unknown_seqs = 1;
159			break;
160		case 'x':		/* do not compress spaces into tabs */
161			compress_spaces = 0;
162			break;
163		case '?':
164		default:
165			usage();
166		}
167
168	if (optind != argc)
169		usage();
170
171	/* this value is in half lines */
172	max_bufd_lines *= 2;
173
174	adjust = cur_col = extra_lines = warned = 0;
175	cur_line = max_line = nflushd_lines = this_line = 0;
176	cur_set = last_set = CS_NORMAL;
177	lines = l = alloc_line();
178
179	while ((ch = getchar()) != EOF) {
180		if (!isgraph(ch)) {
181			switch (ch) {
182			case BS:		/* can't go back further */
183				if (cur_col == 0)
184					continue;
185				--cur_col;
186				continue;
187			case CR:
188				cur_col = 0;
189				continue;
190			case ESC:		/* just ignore EOF */
191				switch(getchar()) {
192				case RLF:
193					cur_line -= 2;
194					break;
195				case RHLF:
196					cur_line--;
197					break;
198				case FHLF:
199					cur_line++;
200					if (cur_line > max_line)
201						max_line = cur_line;
202				}
203				continue;
204			case NL:
205				cur_line += 2;
206				if (cur_line > max_line)
207					max_line = cur_line;
208				cur_col = 0;
209				continue;
210			case SPACE:
211				++cur_col;
212				continue;
213			case SI:
214				cur_set = CS_NORMAL;
215				continue;
216			case SO:
217				cur_set = CS_ALTERNATE;
218				continue;
219			case TAB:		/* adjust column */
220				cur_col |= 7;
221				++cur_col;
222				continue;
223			case VT:
224				cur_line -= 2;
225				continue;
226			}
227			if (!pass_unknown_seqs)
228				continue;
229		}
230
231		/* Must stuff ch in a line - are we at the right one? */
232		if (cur_line != this_line - adjust) {
233			LINE *lnew;
234			int nmove;
235
236			adjust = 0;
237			nmove = cur_line - this_line;
238			if (!fine) {
239				/* round up to next line */
240				if (cur_line & 1) {
241					adjust = 1;
242					nmove++;
243				}
244			}
245			if (nmove < 0) {
246				for (; nmove < 0 && l->l_prev; nmove++)
247					l = l->l_prev;
248				if (nmove) {
249					if (nflushd_lines == 0) {
250						/*
251						 * Allow backup past first
252						 * line if nothing has been
253						 * flushed yet.
254						 */
255						for (; nmove < 0; nmove++) {
256							lnew = alloc_line();
257							l->l_prev = lnew;
258							lnew->l_next = l;
259							l = lines = lnew;
260							extra_lines++;
261						}
262					} else {
263						if (!warned++)
264							dowarn(cur_line);
265						cur_line -= nmove;
266					}
267				}
268			} else {
269				/* may need to allocate here */
270				for (; nmove > 0 && l->l_next; nmove--)
271					l = l->l_next;
272				for (; nmove > 0; nmove--) {
273					lnew = alloc_line();
274					lnew->l_prev = l;
275					l->l_next = lnew;
276					l = lnew;
277				}
278			}
279			this_line = cur_line + adjust;
280			nmove = this_line - nflushd_lines;
281			if (nmove >= max_bufd_lines + BUFFER_MARGIN) {
282				nflushd_lines += nmove - max_bufd_lines;
283				flush_lines(nmove - max_bufd_lines);
284			}
285		}
286		/* grow line's buffer? */
287		if (l->l_line_len + 1 >= l->l_lsize) {
288			int need;
289
290			need = l->l_lsize ? l->l_lsize * 2 : 90;
291			if ((l->l_line = realloc(l->l_line,
292			    (unsigned)need * sizeof(CHAR))) == NULL)
293				err(1, (char *)NULL);
294			l->l_lsize = need;
295		}
296		c = &l->l_line[l->l_line_len++];
297		c->c_char = ch;
298		c->c_set = cur_set;
299		c->c_column = cur_col;
300		/*
301		 * If things are put in out of order, they will need sorting
302		 * when it is flushed.
303		 */
304		if (cur_col < l->l_max_col)
305			l->l_needs_sort = 1;
306		else
307			l->l_max_col = cur_col;
308		cur_col++;
309	}
310	if (max_line == 0)
311		exit(0);	/* no lines, so just exit */
312
313	/* goto the last line that had a character on it */
314	for (; l->l_next; l = l->l_next)
315		this_line++;
316	flush_lines(this_line - nflushd_lines + extra_lines + 1);
317
318	/* make sure we leave things in a sane state */
319	if (last_set != CS_NORMAL)
320		PUTC('\017');
321
322	/* flush out the last few blank lines */
323	nblank_lines = max_line - this_line;
324	if (max_line & 1)
325		nblank_lines++;
326	else if (!nblank_lines)
327		/* missing a \n on the last line? */
328		nblank_lines = 2;
329	flush_blanks();
330	exit(0);
331}
332
333void
334flush_lines(nflush)
335	int nflush;
336{
337	LINE *l;
338
339	while (--nflush >= 0) {
340		l = lines;
341		lines = l->l_next;
342		if (l->l_line) {
343			flush_blanks();
344			flush_line(l);
345		}
346		nblank_lines++;
347		if (l->l_line)
348			(void)free(l->l_line);
349		free_line(l);
350	}
351	if (lines)
352		lines->l_prev = NULL;
353}
354
355/*
356 * Print a number of newline/half newlines.  If fine flag is set, nblank_lines
357 * is the number of half line feeds, otherwise it is the number of whole line
358 * feeds.
359 */
360void
361flush_blanks()
362{
363	int half, i, nb;
364
365	half = 0;
366	nb = nblank_lines;
367	if (nb & 1) {
368		if (fine)
369			half = 1;
370		else
371			nb++;
372	}
373	nb /= 2;
374	for (i = nb; --i >= 0;)
375		PUTC('\n');
376	if (half) {
377		PUTC('\033');
378		PUTC('9');
379		if (!nb)
380			PUTC('\r');
381	}
382	nblank_lines = 0;
383}
384
385/*
386 * Write a line to stdout taking care of space to tab conversion (-h flag)
387 * and character set shifts.
388 */
389void
390flush_line(l)
391	LINE *l;
392{
393	CHAR *c, *endc;
394	int nchars, last_col, this_col;
395
396	last_col = 0;
397	nchars = l->l_line_len;
398
399	if (l->l_needs_sort) {
400		static CHAR *sorted;
401		static int count_size, *count, i, save, sorted_size, tot;
402
403		/*
404		 * Do an O(n) sort on l->l_line by column being careful to
405		 * preserve the order of characters in the same column.
406		 */
407		if (l->l_lsize > sorted_size) {
408			sorted_size = l->l_lsize;
409			if ((sorted = realloc(sorted,
410			    (unsigned)sizeof(CHAR) * sorted_size)) == NULL)
411				err(1, (char *)NULL);
412		}
413		if (l->l_max_col >= count_size) {
414			count_size = l->l_max_col + 1;
415			if ((count = realloc(count,
416			    (unsigned)sizeof(int) * count_size)) == NULL)
417				err(1, (char *)NULL);
418		}
419		memset(count, 0, sizeof(int) * l->l_max_col + 1);
420		for (i = nchars, c = l->l_line; --i >= 0; c++)
421			count[c->c_column]++;
422
423		/*
424		 * calculate running total (shifted down by 1) to use as
425		 * indices into new line.
426		 */
427		for (tot = 0, i = 0; i <= l->l_max_col; i++) {
428			save = count[i];
429			count[i] = tot;
430			tot += save;
431		}
432
433		for (i = nchars, c = l->l_line; --i >= 0; c++)
434			sorted[count[c->c_column]++] = *c;
435		c = sorted;
436	} else
437		c = l->l_line;
438	while (nchars > 0) {
439		this_col = c->c_column;
440		endc = c;
441		do {
442			++endc;
443		} while (--nchars > 0 && this_col == endc->c_column);
444
445		/* if -b only print last character */
446		if (no_backspaces)
447			c = endc - 1;
448
449		if (this_col > last_col) {
450			int nspace = this_col - last_col;
451
452			if (compress_spaces && nspace > 1) {
453				while (1) {
454					int tab_col, tab_size;;
455
456					tab_col = (last_col + 8) & ~7;
457					if (tab_col > this_col)
458						break;
459					tab_size = tab_col - last_col;
460					if (tab_size == 1)
461						PUTC(' ');
462					else
463						PUTC('\t');
464					nspace -= tab_size;
465					last_col = tab_col;
466				}
467			}
468			while (--nspace >= 0)
469				PUTC(' ');
470			last_col = this_col;
471		}
472		last_col++;
473
474		for (;;) {
475			if (c->c_set != last_set) {
476				switch (c->c_set) {
477				case CS_NORMAL:
478					PUTC('\017');
479					break;
480				case CS_ALTERNATE:
481					PUTC('\016');
482				}
483				last_set = c->c_set;
484			}
485			PUTC(c->c_char);
486			if (++c >= endc)
487				break;
488			PUTC('\b');
489		}
490	}
491}
492
493#define	NALLOC 64
494
495static LINE *line_freelist;
496
497LINE *
498alloc_line()
499{
500	LINE *l;
501	int i;
502
503	if (!line_freelist) {
504		if ((l = realloc(NULL, sizeof(LINE) * NALLOC)) == NULL)
505			err(1, (char *)NULL);
506		line_freelist = l;
507		for (i = 1; i < NALLOC; i++, l++)
508			l->l_next = l + 1;
509		l->l_next = NULL;
510	}
511	l = line_freelist;
512	line_freelist = l->l_next;
513
514	memset(l, 0, sizeof(LINE));
515	return (l);
516}
517
518void
519free_line(l)
520	LINE *l;
521{
522
523	l->l_next = line_freelist;
524	line_freelist = l;
525}
526
527void
528usage()
529{
530
531	(void)fprintf(stderr, "usage: col [-bfhpx] [-l nline]\n");
532	exit(1);
533}
534
535void
536dowarn(line)
537	int line;
538{
539
540	warnx("warning: can't back up %s",
541		line < 0 ? "past first line" : "-- line already flushed");
542}
543