xref: /openbsd-src/usr.bin/col/col.c (revision 2b0358df1d88d06ef4139321dd05bd5e05d91eaf)
1 /*	$OpenBSD: col.c,v 1.10 2007/05/01 01:26:19 jdixon Exp $	*/
2 /*	$NetBSD: col.c,v 1.7 1995/09/02 05:48:50 jtc Exp $	*/
3 
4 /*-
5  * Copyright (c) 1990, 1993, 1994
6  *	The Regents of the University of California.  All rights reserved.
7  *
8  * This code is derived from software contributed to Berkeley by
9  * Michael Rendell of the Memorial University of Newfoundland.
10  *
11  * Redistribution and use in source and binary forms, with or without
12  * modification, are permitted provided that the following conditions
13  * are met:
14  * 1. Redistributions of source code must retain the above copyright
15  *    notice, this list of conditions and the following disclaimer.
16  * 2. Redistributions in binary form must reproduce the above copyright
17  *    notice, this list of conditions and the following disclaimer in the
18  *    documentation and/or other materials provided with the distribution.
19  * 3. Neither the name of the University nor the names of its contributors
20  *    may be used to endorse or promote products derived from this software
21  *    without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33  * SUCH DAMAGE.
34  */
35 
36 #ifndef lint
37 static char copyright[] =
38 "@(#) Copyright (c) 1990, 1993, 1994\n\
39 	The Regents of the University of California.  All rights reserved.\n";
40 #endif /* not lint */
41 
42 #ifndef lint
43 #if 0
44 static char sccsid[] = "@(#)col.c	8.5 (Berkeley) 5/4/95";
45 #endif
46 static char rcsid[] = "$OpenBSD: col.c,v 1.10 2007/05/01 01:26:19 jdixon Exp $";
47 #endif /* not lint */
48 
49 #include <ctype.h>
50 #include <err.h>
51 #include <string.h>
52 #include <stdio.h>
53 #include <stdlib.h>
54 #include <unistd.h>
55 #include <limits.h>
56 
57 #define	BS	'\b'		/* backspace */
58 #define	TAB	'\t'		/* tab */
59 #define	SPACE	' '		/* space */
60 #define	NL	'\n'		/* newline */
61 #define	CR	'\r'		/* carriage return */
62 #define	ESC	'\033'		/* escape */
63 #define	SI	'\017'		/* shift in to normal character set */
64 #define	SO	'\016'		/* shift out to alternate character set */
65 #define	VT	'\013'		/* vertical tab (aka reverse line feed) */
66 #define	RLF	'\007'		/* ESC-07 reverse line feed */
67 #define	RHLF	'\010'		/* ESC-010 reverse half-line feed */
68 #define	FHLF	'\011'		/* ESC-011 forward half-line feed */
69 
70 /* build up at least this many lines before flushing them out */
71 #define	BUFFER_MARGIN		32
72 
73 typedef char CSET;
74 
75 typedef struct char_str {
76 #define	CS_NORMAL	1
77 #define	CS_ALTERNATE	2
78 	short		c_column;	/* column character is in */
79 	CSET		c_set;		/* character set (currently only 2) */
80 	char		c_char;		/* character in question */
81 } CHAR;
82 
83 typedef struct line_str LINE;
84 struct line_str {
85 	CHAR	*l_line;		/* characters on the line */
86 	LINE	*l_prev;		/* previous line */
87 	LINE	*l_next;		/* next line */
88 	int	l_lsize;		/* allocated sizeof l_line */
89 	int	l_line_len;		/* strlen(l_line) */
90 	int	l_needs_sort;		/* set if chars went in out of order */
91 	int	l_max_col;		/* max column in the line */
92 };
93 
94 LINE   *alloc_line(void);
95 void	dowarn(int);
96 void	flush_line(LINE *);
97 void	flush_lines(int);
98 void	flush_blanks(void);
99 void	free_line(LINE *);
100 void	usage(void);
101 void   *xmalloc(void *, size_t);
102 
103 CSET	last_set;		/* char_set of last char printed */
104 LINE   *lines;
105 int	compress_spaces;	/* if doing space -> tab conversion */
106 int	fine;			/* if `fine' resolution (half lines) */
107 int	max_bufd_lines;		/* max # lines to keep in memory */
108 int	nblank_lines;		/* # blanks after last flushed line */
109 int	no_backspaces;		/* if not to output any backspaces */
110 
111 #define	PUTC(ch) \
112 	if (putchar(ch) == EOF) \
113 		err(1, "stdout");
114 
115 int
116 main(int argc, char *argv[])
117 {
118 	int ch;
119 	CHAR *c;
120 	CSET cur_set;			/* current character set */
121 	LINE *l;			/* current line */
122 	int extra_lines;		/* # of lines above first line */
123 	int cur_col;			/* current column */
124 	int cur_line;			/* line number of current position */
125 	int max_line;			/* max value of cur_line */
126 	int this_line;			/* line l points to */
127 	int nflushd_lines;		/* number of lines that were flushed */
128 	int adjust, opt, warned;
129 	const char *errstr;
130 
131 	max_bufd_lines = 128;
132 	compress_spaces = 1;		/* compress spaces into tabs */
133 	while ((opt = getopt(argc, argv, "bfhl:x")) != -1)
134 		switch (opt) {
135 		case 'b':		/* do not output backspaces */
136 			no_backspaces = 1;
137 			break;
138 		case 'f':		/* allow half forward line feeds */
139 			fine = 1;
140 			break;
141 		case 'h':		/* compress spaces into tabs */
142 			compress_spaces = 1;
143 			break;
144 		case 'l':		/* buffered line count */
145 			max_bufd_lines = strtonum(optarg, 1, INT_MAX, &errstr);
146 			if (errstr != NULL)
147 				errx(1, "bad -l argument, %s: %s", errstr,
148 					optarg);
149 			break;
150 		case 'x':		/* do not compress spaces into tabs */
151 			compress_spaces = 0;
152 			break;
153 		case '?':
154 		default:
155 			usage();
156 		}
157 
158 	if (optind != argc)
159 		usage();
160 
161 	/* this value is in half lines */
162 	max_bufd_lines *= 2;
163 
164 	adjust = cur_col = extra_lines = warned = 0;
165 	cur_line = max_line = nflushd_lines = this_line = 0;
166 	cur_set = last_set = CS_NORMAL;
167 	lines = l = alloc_line();
168 
169 	while ((ch = getchar()) != EOF) {
170 		if (!isgraph(ch)) {
171 			switch (ch) {
172 			case BS:		/* can't go back further */
173 				if (cur_col == 0)
174 					continue;
175 				--cur_col;
176 				continue;
177 			case CR:
178 				cur_col = 0;
179 				continue;
180 			case ESC:		/* just ignore EOF */
181 				switch(getchar()) {
182 				case RLF:
183 					cur_line -= 2;
184 					break;
185 				case RHLF:
186 					cur_line--;
187 					break;
188 				case FHLF:
189 					cur_line++;
190 					if (cur_line > max_line)
191 						max_line = cur_line;
192 				}
193 				continue;
194 			case NL:
195 				cur_line += 2;
196 				if (cur_line > max_line)
197 					max_line = cur_line;
198 				cur_col = 0;
199 				continue;
200 			case SPACE:
201 				++cur_col;
202 				continue;
203 			case SI:
204 				cur_set = CS_NORMAL;
205 				continue;
206 			case SO:
207 				cur_set = CS_ALTERNATE;
208 				continue;
209 			case TAB:		/* adjust column */
210 				cur_col |= 7;
211 				++cur_col;
212 				continue;
213 			case VT:
214 				cur_line -= 2;
215 				continue;
216 			}
217 			continue;
218 		}
219 
220 		/* Must stuff ch in a line - are we at the right one? */
221 		if (cur_line != this_line - adjust) {
222 			LINE *lnew;
223 			int nmove;
224 
225 			adjust = 0;
226 			nmove = cur_line - this_line;
227 			if (!fine) {
228 				/* round up to next line */
229 				if (cur_line & 1) {
230 					adjust = 1;
231 					nmove++;
232 				}
233 			}
234 			if (nmove < 0) {
235 				for (; nmove < 0 && l->l_prev; nmove++)
236 					l = l->l_prev;
237 				if (nmove) {
238 					if (nflushd_lines == 0) {
239 						/*
240 						 * Allow backup past first
241 						 * line if nothing has been
242 						 * flushed yet.
243 						 */
244 						for (; nmove < 0; nmove++) {
245 							lnew = alloc_line();
246 							l->l_prev = lnew;
247 							lnew->l_next = l;
248 							l = lines = lnew;
249 							extra_lines++;
250 						}
251 					} else {
252 						if (!warned++)
253 							dowarn(cur_line);
254 						cur_line -= nmove;
255 					}
256 				}
257 			} else {
258 				/* may need to allocate here */
259 				for (; nmove > 0 && l->l_next; nmove--)
260 					l = l->l_next;
261 				for (; nmove > 0; nmove--) {
262 					lnew = alloc_line();
263 					lnew->l_prev = l;
264 					l->l_next = lnew;
265 					l = lnew;
266 				}
267 			}
268 			this_line = cur_line + adjust;
269 			nmove = this_line - nflushd_lines;
270 			if (nmove >= max_bufd_lines + BUFFER_MARGIN) {
271 				nflushd_lines += nmove - max_bufd_lines;
272 				flush_lines(nmove - max_bufd_lines);
273 			}
274 		}
275 		/* grow line's buffer? */
276 		if (l->l_line_len + 1 >= l->l_lsize) {
277 			int need;
278 
279 			need = l->l_lsize ? l->l_lsize * 2 : 90;
280 			l->l_line = (CHAR *)xmalloc((void *) l->l_line,
281 			    (unsigned) need * sizeof(CHAR));
282 			l->l_lsize = need;
283 		}
284 		c = &l->l_line[l->l_line_len++];
285 		c->c_char = ch;
286 		c->c_set = cur_set;
287 		c->c_column = cur_col;
288 		/*
289 		 * If things are put in out of order, they will need sorting
290 		 * when it is flushed.
291 		 */
292 		if (cur_col < l->l_max_col)
293 			l->l_needs_sort = 1;
294 		else
295 			l->l_max_col = cur_col;
296 		cur_col++;
297 	}
298 	if (max_line == 0)
299 		exit(0);	/* no lines, so just exit */
300 
301 	/* goto the last line that had a character on it */
302 	for (; l->l_next; l = l->l_next)
303 		this_line++;
304 	flush_lines(this_line - nflushd_lines + extra_lines + 1);
305 
306 	/* make sure we leave things in a sane state */
307 	if (last_set != CS_NORMAL)
308 		PUTC('\017');
309 
310 	/* flush out the last few blank lines */
311 	nblank_lines = max_line - this_line;
312 	if (max_line & 1)
313 		nblank_lines++;
314 	else if (!nblank_lines)
315 		/* missing a \n on the last line? */
316 		nblank_lines = 2;
317 	flush_blanks();
318 	exit(0);
319 }
320 
321 void
322 flush_lines(int nflush)
323 {
324 	LINE *l;
325 
326 	while (--nflush >= 0) {
327 		l = lines;
328 		lines = l->l_next;
329 		if (l->l_line) {
330 			flush_blanks();
331 			flush_line(l);
332 		}
333 		nblank_lines++;
334 		if (l->l_line)
335 			(void)free((void *)l->l_line);
336 		free_line(l);
337 	}
338 	if (lines)
339 		lines->l_prev = NULL;
340 }
341 
342 /*
343  * Print a number of newline/half newlines.  If fine flag is set, nblank_lines
344  * is the number of half line feeds, otherwise it is the number of whole line
345  * feeds.
346  */
347 void
348 flush_blanks(void)
349 {
350 	int half, i, nb;
351 
352 	half = 0;
353 	nb = nblank_lines;
354 	if (nb & 1) {
355 		if (fine)
356 			half = 1;
357 		else
358 			nb++;
359 	}
360 	nb /= 2;
361 	for (i = nb; --i >= 0;)
362 		PUTC('\n');
363 	if (half) {
364 		PUTC('\033');
365 		PUTC('9');
366 		if (!nb)
367 			PUTC('\r');
368 	}
369 	nblank_lines = 0;
370 }
371 
372 /*
373  * Write a line to stdout taking care of space to tab conversion (-h flag)
374  * and character set shifts.
375  */
376 void
377 flush_line(LINE *l)
378 {
379 	CHAR *c, *endc;
380 	int nchars, last_col, this_col;
381 
382 	last_col = 0;
383 	nchars = l->l_line_len;
384 
385 	if (l->l_needs_sort) {
386 		static CHAR *sorted;
387 		static int count_size, *count, i, save, sorted_size, tot;
388 
389 		/*
390 		 * Do an O(n) sort on l->l_line by column being careful to
391 		 * preserve the order of characters in the same column.
392 		 */
393 		if (l->l_lsize > sorted_size) {
394 			sorted_size = l->l_lsize;
395 			sorted = (CHAR *)xmalloc((void *)sorted,
396 			    (unsigned)sizeof(CHAR) * sorted_size);
397 		}
398 		if (l->l_max_col >= count_size) {
399 			count_size = l->l_max_col + 1;
400 			count = (int *)xmalloc((void *)count,
401 			    (unsigned)sizeof(int) * count_size);
402 		}
403 		memset((char *)count, 0, sizeof(int) * l->l_max_col + 1);
404 		for (i = nchars, c = l->l_line; --i >= 0; c++)
405 			count[c->c_column]++;
406 
407 		/*
408 		 * calculate running total (shifted down by 1) to use as
409 		 * indices into new line.
410 		 */
411 		for (tot = 0, i = 0; i <= l->l_max_col; i++) {
412 			save = count[i];
413 			count[i] = tot;
414 			tot += save;
415 		}
416 
417 		for (i = nchars, c = l->l_line; --i >= 0; c++)
418 			sorted[count[c->c_column]++] = *c;
419 		c = sorted;
420 	} else
421 		c = l->l_line;
422 	while (nchars > 0) {
423 		this_col = c->c_column;
424 		endc = c;
425 		do {
426 			++endc;
427 		} while (--nchars > 0 && this_col == endc->c_column);
428 
429 		/* if -b only print last character */
430 		if (no_backspaces)
431 			c = endc - 1;
432 
433 		if (this_col > last_col) {
434 			int nspace = this_col - last_col;
435 
436 			if (compress_spaces && nspace > 1) {
437 				int ntabs;
438 
439 				ntabs = ((last_col % 8) + nspace) / 8;
440 				if (ntabs) {
441 					nspace -= (ntabs * 8) - (last_col % 8);
442 					while (--ntabs >= 0)
443 						PUTC('\t');
444 				}
445 			}
446 			while (--nspace >= 0)
447 				PUTC(' ');
448 			last_col = this_col;
449 		}
450 		last_col++;
451 
452 		for (;;) {
453 			if (c->c_set != last_set) {
454 				switch (c->c_set) {
455 				case CS_NORMAL:
456 					PUTC('\017');
457 					break;
458 				case CS_ALTERNATE:
459 					PUTC('\016');
460 				}
461 				last_set = c->c_set;
462 			}
463 			PUTC(c->c_char);
464 			if (++c >= endc)
465 				break;
466 			PUTC('\b');
467 		}
468 	}
469 }
470 
471 #define	NALLOC 64
472 
473 static LINE *line_freelist;
474 
475 LINE *
476 alloc_line(void)
477 {
478 	LINE *l;
479 	int i;
480 
481 	if (!line_freelist) {
482 		l = (LINE *)xmalloc(NULL, sizeof(LINE) * NALLOC);
483 		line_freelist = l;
484 		for (i = 1; i < NALLOC; i++, l++)
485 			l->l_next = l + 1;
486 		l->l_next = NULL;
487 	}
488 	l = line_freelist;
489 	line_freelist = l->l_next;
490 
491 	memset(l, 0, sizeof(LINE));
492 	return (l);
493 }
494 
495 void
496 free_line(LINE *l)
497 {
498 
499 	l->l_next = line_freelist;
500 	line_freelist = l;
501 }
502 
503 void *
504 xmalloc(void *p, size_t size)
505 {
506 
507 	if (!(p = (void *)realloc(p, size)))
508 		err(1, "realloc failed");
509 	return (p);
510 }
511 
512 void
513 usage(void)
514 {
515 	(void)fprintf(stderr, "usage: col [-bfhx] [-l num]\n");
516 	exit(1);
517 }
518 
519 void
520 dowarn(int line)
521 {
522 
523 	warnx("warning: can't back up %s",
524 		line < 0 ? "past first line" : "-- line already flushed");
525 }
526