xref: /freebsd/usr.bin/col/col.c (revision 2be1a816b9ff69588e55be0a84cbe2a31efc0f2f)
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
38 static 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
45 static char sccsid[] = "@(#)col.c	8.5 (Berkeley) 5/4/95";
46 #endif
47 #endif
48 
49 #include <sys/cdefs.h>
50 __FBSDID("$FreeBSD$");
51 
52 #include <err.h>
53 #include <locale.h>
54 #include <stdio.h>
55 #include <stdlib.h>
56 #include <string.h>
57 #include <unistd.h>
58 #include <wchar.h>
59 #include <wctype.h>
60 
61 #define	BS	'\b'		/* backspace */
62 #define	TAB	'\t'		/* tab */
63 #define	SPACE	' '		/* space */
64 #define	NL	'\n'		/* newline */
65 #define	CR	'\r'		/* carriage return */
66 #define	ESC	'\033'		/* escape */
67 #define	SI	'\017'		/* shift in to normal character set */
68 #define	SO	'\016'		/* shift out to alternate character set */
69 #define	VT	'\013'		/* vertical tab (aka reverse line feed) */
70 #define	RLF	'\007'		/* ESC-07 reverse line feed */
71 #define	RHLF	'\010'		/* ESC-010 reverse half-line feed */
72 #define	FHLF	'\011'		/* ESC-011 forward half-line feed */
73 
74 /* build up at least this many lines before flushing them out */
75 #define	BUFFER_MARGIN		32
76 
77 typedef char CSET;
78 
79 typedef struct char_str {
80 #define	CS_NORMAL	1
81 #define	CS_ALTERNATE	2
82 	short		c_column;	/* column character is in */
83 	CSET		c_set;		/* character set (currently only 2) */
84 	wchar_t		c_char;		/* character in question */
85 	int		c_width;	/* character width */
86 } CHAR;
87 
88 typedef struct line_str LINE;
89 struct line_str {
90 	CHAR	*l_line;		/* characters on the line */
91 	LINE	*l_prev;		/* previous line */
92 	LINE	*l_next;		/* next line */
93 	int	l_lsize;		/* allocated sizeof l_line */
94 	int	l_line_len;		/* strlen(l_line) */
95 	int	l_needs_sort;		/* set if chars went in out of order */
96 	int	l_max_col;		/* max column in the line */
97 };
98 
99 LINE   *alloc_line(void);
100 void	dowarn(int);
101 void	flush_line(LINE *);
102 void	flush_lines(int);
103 void	flush_blanks(void);
104 void	free_line(LINE *);
105 void	usage(void);
106 
107 CSET	last_set;		/* char_set of last char printed */
108 LINE   *lines;
109 int	compress_spaces;	/* if doing space -> tab conversion */
110 int	fine;			/* if `fine' resolution (half lines) */
111 int	max_bufd_lines;		/* max # lines to keep in memory */
112 int	nblank_lines;		/* # blanks after last flushed line */
113 int	no_backspaces;		/* if not to output any backspaces */
114 int	pass_unknown_seqs;	/* pass unknown control sequences */
115 
116 #define	PUTC(ch) \
117 	do {					\
118 		if (putwchar(ch) == WEOF)	\
119 			errx(1, "write error");	\
120 	} while (0)
121 
122 int
123 main(int argc, char **argv)
124 {
125 	wint_t ch;
126 	CHAR *c;
127 	CSET cur_set;			/* current character set */
128 	LINE *l;			/* current line */
129 	int extra_lines;		/* # of lines above first line */
130 	int cur_col;			/* current column */
131 	int cur_line;			/* line number of current position */
132 	int max_line;			/* max value of cur_line */
133 	int this_line;			/* line l points to */
134 	int nflushd_lines;		/* number of lines that were flushed */
135 	int adjust, opt, warned, width;
136 
137 	(void)setlocale(LC_CTYPE, "");
138 
139 	max_bufd_lines = 128;
140 	compress_spaces = 1;		/* compress spaces into tabs */
141 	while ((opt = getopt(argc, argv, "bfhl:px")) != -1)
142 		switch (opt) {
143 		case 'b':		/* do not output backspaces */
144 			no_backspaces = 1;
145 			break;
146 		case 'f':		/* allow half forward line feeds */
147 			fine = 1;
148 			break;
149 		case 'h':		/* compress spaces into tabs */
150 			compress_spaces = 1;
151 			break;
152 		case 'l':		/* buffered line count */
153 			if ((max_bufd_lines = atoi(optarg)) <= 0)
154 				errx(1, "bad -l argument %s", optarg);
155 			break;
156 		case 'p':		/* pass unknown control sequences */
157 			pass_unknown_seqs = 1;
158 			break;
159 		case 'x':		/* do not compress spaces into tabs */
160 			compress_spaces = 0;
161 			break;
162 		case '?':
163 		default:
164 			usage();
165 		}
166 
167 	if (optind != argc)
168 		usage();
169 
170 	/* this value is in half lines */
171 	max_bufd_lines *= 2;
172 
173 	adjust = cur_col = extra_lines = warned = 0;
174 	cur_line = max_line = nflushd_lines = this_line = 0;
175 	cur_set = last_set = CS_NORMAL;
176 	lines = l = alloc_line();
177 
178 	while ((ch = getwchar()) != WEOF) {
179 		if (!iswgraph(ch)) {
180 			switch (ch) {
181 			case BS:		/* can't go back further */
182 				if (cur_col == 0)
183 					continue;
184 				--cur_col;
185 				continue;
186 			case CR:
187 				cur_col = 0;
188 				continue;
189 			case ESC:		/* just ignore EOF */
190 				switch(getwchar()) {
191 				case RLF:
192 					cur_line -= 2;
193 					break;
194 				case RHLF:
195 					cur_line--;
196 					break;
197 				case FHLF:
198 					cur_line++;
199 					if (cur_line > max_line)
200 						max_line = cur_line;
201 				}
202 				continue;
203 			case NL:
204 				cur_line += 2;
205 				if (cur_line > max_line)
206 					max_line = cur_line;
207 				cur_col = 0;
208 				continue;
209 			case SPACE:
210 				++cur_col;
211 				continue;
212 			case SI:
213 				cur_set = CS_NORMAL;
214 				continue;
215 			case SO:
216 				cur_set = CS_ALTERNATE;
217 				continue;
218 			case TAB:		/* adjust column */
219 				cur_col |= 7;
220 				++cur_col;
221 				continue;
222 			case VT:
223 				cur_line -= 2;
224 				continue;
225 			}
226 			if (iswspace(ch)) {
227 				if ((width = wcwidth(ch)) > 0)
228 					cur_col += width;
229 				continue;
230 			}
231 			if (!pass_unknown_seqs)
232 				continue;
233 		}
234 
235 		/* Must stuff ch in a line - are we at the right one? */
236 		if (cur_line != this_line - adjust) {
237 			LINE *lnew;
238 			int nmove;
239 
240 			adjust = 0;
241 			nmove = cur_line - this_line;
242 			if (!fine) {
243 				/* round up to next line */
244 				if (cur_line & 1) {
245 					adjust = 1;
246 					nmove++;
247 				}
248 			}
249 			if (nmove < 0) {
250 				for (; nmove < 0 && l->l_prev; nmove++)
251 					l = l->l_prev;
252 				if (nmove) {
253 					if (nflushd_lines == 0) {
254 						/*
255 						 * Allow backup past first
256 						 * line if nothing has been
257 						 * flushed yet.
258 						 */
259 						for (; nmove < 0; nmove++) {
260 							lnew = alloc_line();
261 							l->l_prev = lnew;
262 							lnew->l_next = l;
263 							l = lines = lnew;
264 							extra_lines++;
265 						}
266 					} else {
267 						if (!warned++)
268 							dowarn(cur_line);
269 						cur_line -= nmove;
270 					}
271 				}
272 			} else {
273 				/* may need to allocate here */
274 				for (; nmove > 0 && l->l_next; nmove--)
275 					l = l->l_next;
276 				for (; nmove > 0; nmove--) {
277 					lnew = alloc_line();
278 					lnew->l_prev = l;
279 					l->l_next = lnew;
280 					l = lnew;
281 				}
282 			}
283 			this_line = cur_line + adjust;
284 			nmove = this_line - nflushd_lines;
285 			if (nmove >= max_bufd_lines + BUFFER_MARGIN) {
286 				nflushd_lines += nmove - max_bufd_lines;
287 				flush_lines(nmove - max_bufd_lines);
288 			}
289 		}
290 		/* grow line's buffer? */
291 		if (l->l_line_len + 1 >= l->l_lsize) {
292 			int need;
293 
294 			need = l->l_lsize ? l->l_lsize * 2 : 90;
295 			if ((l->l_line = realloc(l->l_line,
296 			    (unsigned)need * sizeof(CHAR))) == NULL)
297 				err(1, (char *)NULL);
298 			l->l_lsize = need;
299 		}
300 		c = &l->l_line[l->l_line_len++];
301 		c->c_char = ch;
302 		c->c_set = cur_set;
303 		c->c_column = cur_col;
304 		c->c_width = wcwidth(ch);
305 		/*
306 		 * If things are put in out of order, they will need sorting
307 		 * when it is flushed.
308 		 */
309 		if (cur_col < l->l_max_col)
310 			l->l_needs_sort = 1;
311 		else
312 			l->l_max_col = cur_col;
313 		if (c->c_width > 0)
314 			cur_col += c->c_width;
315 	}
316 	if (ferror(stdin))
317 		err(1, NULL);
318 	if (max_line == 0)
319 		exit(0);	/* no lines, so just exit */
320 
321 	/* goto the last line that had a character on it */
322 	for (; l->l_next; l = l->l_next)
323 		this_line++;
324 	flush_lines(this_line - nflushd_lines + extra_lines + 1);
325 
326 	/* make sure we leave things in a sane state */
327 	if (last_set != CS_NORMAL)
328 		PUTC('\017');
329 
330 	/* flush out the last few blank lines */
331 	nblank_lines = max_line - this_line;
332 	if (max_line & 1)
333 		nblank_lines++;
334 	else if (!nblank_lines)
335 		/* missing a \n on the last line? */
336 		nblank_lines = 2;
337 	flush_blanks();
338 	exit(0);
339 }
340 
341 void
342 flush_lines(int nflush)
343 {
344 	LINE *l;
345 
346 	while (--nflush >= 0) {
347 		l = lines;
348 		lines = l->l_next;
349 		if (l->l_line) {
350 			flush_blanks();
351 			flush_line(l);
352 		}
353 		nblank_lines++;
354 		if (l->l_line)
355 			(void)free(l->l_line);
356 		free_line(l);
357 	}
358 	if (lines)
359 		lines->l_prev = NULL;
360 }
361 
362 /*
363  * Print a number of newline/half newlines.  If fine flag is set, nblank_lines
364  * is the number of half line feeds, otherwise it is the number of whole line
365  * feeds.
366  */
367 void
368 flush_blanks(void)
369 {
370 	int half, i, nb;
371 
372 	half = 0;
373 	nb = nblank_lines;
374 	if (nb & 1) {
375 		if (fine)
376 			half = 1;
377 		else
378 			nb++;
379 	}
380 	nb /= 2;
381 	for (i = nb; --i >= 0;)
382 		PUTC('\n');
383 	if (half) {
384 		PUTC('\033');
385 		PUTC('9');
386 		if (!nb)
387 			PUTC('\r');
388 	}
389 	nblank_lines = 0;
390 }
391 
392 /*
393  * Write a line to stdout taking care of space to tab conversion (-h flag)
394  * and character set shifts.
395  */
396 void
397 flush_line(LINE *l)
398 {
399 	CHAR *c, *endc;
400 	int i, j, nchars, last_col, save, this_col, tot;
401 
402 	last_col = 0;
403 	nchars = l->l_line_len;
404 
405 	if (l->l_needs_sort) {
406 		static CHAR *sorted;
407 		static int count_size, *count, sorted_size;
408 
409 		/*
410 		 * Do an O(n) sort on l->l_line by column being careful to
411 		 * preserve the order of characters in the same column.
412 		 */
413 		if (l->l_lsize > sorted_size) {
414 			sorted_size = l->l_lsize;
415 			if ((sorted = realloc(sorted,
416 			    (unsigned)sizeof(CHAR) * sorted_size)) == NULL)
417 				err(1, (char *)NULL);
418 		}
419 		if (l->l_max_col >= count_size) {
420 			count_size = l->l_max_col + 1;
421 			if ((count = realloc(count,
422 			    (unsigned)sizeof(int) * count_size)) == NULL)
423 				err(1, (char *)NULL);
424 		}
425 		memset(count, 0, sizeof(int) * l->l_max_col + 1);
426 		for (i = nchars, c = l->l_line; --i >= 0; c++)
427 			count[c->c_column]++;
428 
429 		/*
430 		 * calculate running total (shifted down by 1) to use as
431 		 * indices into new line.
432 		 */
433 		for (tot = 0, i = 0; i <= l->l_max_col; i++) {
434 			save = count[i];
435 			count[i] = tot;
436 			tot += save;
437 		}
438 
439 		for (i = nchars, c = l->l_line; --i >= 0; c++)
440 			sorted[count[c->c_column]++] = *c;
441 		c = sorted;
442 	} else
443 		c = l->l_line;
444 	while (nchars > 0) {
445 		this_col = c->c_column;
446 		endc = c;
447 		do {
448 			++endc;
449 		} while (--nchars > 0 && this_col == endc->c_column);
450 
451 		/* if -b only print last character */
452 		if (no_backspaces) {
453 			c = endc - 1;
454 			if (nchars > 0 &&
455 			    this_col + c->c_width > endc->c_column)
456 				continue;
457 		}
458 
459 		if (this_col > last_col) {
460 			int nspace = this_col - last_col;
461 
462 			if (compress_spaces && nspace > 1) {
463 				while (1) {
464 					int tab_col, tab_size;;
465 
466 					tab_col = (last_col + 8) & ~7;
467 					if (tab_col > this_col)
468 						break;
469 					tab_size = tab_col - last_col;
470 					if (tab_size == 1)
471 						PUTC(' ');
472 					else
473 						PUTC('\t');
474 					nspace -= tab_size;
475 					last_col = tab_col;
476 				}
477 			}
478 			while (--nspace >= 0)
479 				PUTC(' ');
480 			last_col = this_col;
481 		}
482 
483 		for (;;) {
484 			if (c->c_set != last_set) {
485 				switch (c->c_set) {
486 				case CS_NORMAL:
487 					PUTC('\017');
488 					break;
489 				case CS_ALTERNATE:
490 					PUTC('\016');
491 				}
492 				last_set = c->c_set;
493 			}
494 			PUTC(c->c_char);
495 			if ((c + 1) < endc)
496 				for (j = 0; j < c->c_width; j++)
497 					PUTC('\b');
498 			if (++c >= endc)
499 				break;
500 		}
501 		last_col += (c - 1)->c_width;
502 	}
503 }
504 
505 #define	NALLOC 64
506 
507 static LINE *line_freelist;
508 
509 LINE *
510 alloc_line(void)
511 {
512 	LINE *l;
513 	int i;
514 
515 	if (!line_freelist) {
516 		if ((l = realloc(NULL, sizeof(LINE) * NALLOC)) == NULL)
517 			err(1, (char *)NULL);
518 		line_freelist = l;
519 		for (i = 1; i < NALLOC; i++, l++)
520 			l->l_next = l + 1;
521 		l->l_next = NULL;
522 	}
523 	l = line_freelist;
524 	line_freelist = l->l_next;
525 
526 	memset(l, 0, sizeof(LINE));
527 	return (l);
528 }
529 
530 void
531 free_line(LINE *l)
532 {
533 
534 	l->l_next = line_freelist;
535 	line_freelist = l;
536 }
537 
538 void
539 usage(void)
540 {
541 
542 	(void)fprintf(stderr, "usage: col [-bfhpx] [-l nline]\n");
543 	exit(1);
544 }
545 
546 void
547 dowarn(int line)
548 {
549 
550 	warnx("warning: can't back up %s",
551 		line < 0 ? "past first line" : "-- line already flushed");
552 }
553