xref: /freebsd/usr.bin/col/col.c (revision ff0ba87247820afbdfdc1b307c803f7923d0e4d3)
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  * 4. Neither the name of the University nor the names of its contributors
17  *    may be used to endorse or promote products derived from this software
18  *    without specific prior written permission.
19  *
20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30  * SUCH DAMAGE.
31  */
32 
33 #ifndef lint
34 static const char copyright[] =
35 "@(#) Copyright (c) 1990, 1993, 1994\n\
36 	The Regents of the University of California.  All rights reserved.\n";
37 #endif
38 
39 #if 0
40 #ifndef lint
41 static char sccsid[] = "@(#)col.c	8.5 (Berkeley) 5/4/95";
42 #endif
43 #endif
44 
45 #include <sys/cdefs.h>
46 __FBSDID("$FreeBSD$");
47 
48 #include <err.h>
49 #include <locale.h>
50 #include <stdio.h>
51 #include <stdlib.h>
52 #include <string.h>
53 #include <unistd.h>
54 #include <wchar.h>
55 #include <wctype.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 	wchar_t		c_char;		/* character in question */
81 	int		c_width;	/* character width */
82 } CHAR;
83 
84 typedef struct line_str LINE;
85 struct line_str {
86 	CHAR	*l_line;		/* characters on the line */
87 	LINE	*l_prev;		/* previous line */
88 	LINE	*l_next;		/* next line */
89 	int	l_lsize;		/* allocated sizeof l_line */
90 	int	l_line_len;		/* strlen(l_line) */
91 	int	l_needs_sort;		/* set if chars went in out of order */
92 	int	l_max_col;		/* max column in the line */
93 };
94 
95 static LINE   *alloc_line(void);
96 static void	dowarn(int);
97 static void	flush_line(LINE *);
98 static void	flush_lines(int);
99 static void	flush_blanks(void);
100 static void	free_line(LINE *);
101 static void	usage(void);
102 
103 static CSET	last_set;		/* char_set of last char printed */
104 static LINE    *lines;
105 static int	compress_spaces;	/* if doing space -> tab conversion */
106 static int	fine;			/* if `fine' resolution (half lines) */
107 static int	max_bufd_lines;		/* max # lines to keep in memory */
108 static int	nblank_lines;		/* # blanks after last flushed line */
109 static int	no_backspaces;		/* if not to output any backspaces */
110 static int	pass_unknown_seqs;	/* pass unknown control sequences */
111 
112 #define	PUTC(ch) \
113 	do {					\
114 		if (putwchar(ch) == WEOF)	\
115 			errx(1, "write error");	\
116 	} while (0)
117 
118 int
119 main(int argc, char **argv)
120 {
121 	wint_t ch;
122 	CHAR *c;
123 	CSET cur_set;			/* current character set */
124 	LINE *l;			/* current line */
125 	int extra_lines;		/* # of lines above first line */
126 	int cur_col;			/* current column */
127 	int cur_line;			/* line number of current position */
128 	int max_line;			/* max value of cur_line */
129 	int this_line;			/* line l points to */
130 	int nflushd_lines;		/* number of lines that were flushed */
131 	int adjust, opt, warned, width;
132 
133 	(void)setlocale(LC_CTYPE, "");
134 
135 	max_bufd_lines = 128;
136 	compress_spaces = 1;		/* compress spaces into tabs */
137 	while ((opt = getopt(argc, argv, "bfhl:px")) != -1)
138 		switch (opt) {
139 		case 'b':		/* do not output backspaces */
140 			no_backspaces = 1;
141 			break;
142 		case 'f':		/* allow half forward line feeds */
143 			fine = 1;
144 			break;
145 		case 'h':		/* compress spaces into tabs */
146 			compress_spaces = 1;
147 			break;
148 		case 'l':		/* buffered line count */
149 			if ((max_bufd_lines = atoi(optarg)) <= 0)
150 				errx(1, "bad -l argument %s", optarg);
151 			break;
152 		case 'p':		/* pass unknown control sequences */
153 			pass_unknown_seqs = 1;
154 			break;
155 		case 'x':		/* do not compress spaces into tabs */
156 			compress_spaces = 0;
157 			break;
158 		case '?':
159 		default:
160 			usage();
161 		}
162 
163 	if (optind != argc)
164 		usage();
165 
166 	/* this value is in half lines */
167 	max_bufd_lines *= 2;
168 
169 	adjust = cur_col = extra_lines = warned = 0;
170 	cur_line = max_line = nflushd_lines = this_line = 0;
171 	cur_set = last_set = CS_NORMAL;
172 	lines = l = alloc_line();
173 
174 	while ((ch = getwchar()) != WEOF) {
175 		if (!iswgraph(ch)) {
176 			switch (ch) {
177 			case BS:		/* can't go back further */
178 				if (cur_col == 0)
179 					continue;
180 				--cur_col;
181 				continue;
182 			case CR:
183 				cur_col = 0;
184 				continue;
185 			case ESC:		/* just ignore EOF */
186 				switch(getwchar()) {
187 				case RLF:
188 					cur_line -= 2;
189 					break;
190 				case RHLF:
191 					cur_line--;
192 					break;
193 				case FHLF:
194 					cur_line++;
195 					if (cur_line > max_line)
196 						max_line = cur_line;
197 				}
198 				continue;
199 			case NL:
200 				cur_line += 2;
201 				if (cur_line > max_line)
202 					max_line = cur_line;
203 				cur_col = 0;
204 				continue;
205 			case SPACE:
206 				++cur_col;
207 				continue;
208 			case SI:
209 				cur_set = CS_NORMAL;
210 				continue;
211 			case SO:
212 				cur_set = CS_ALTERNATE;
213 				continue;
214 			case TAB:		/* adjust column */
215 				cur_col |= 7;
216 				++cur_col;
217 				continue;
218 			case VT:
219 				cur_line -= 2;
220 				continue;
221 			}
222 			if (iswspace(ch)) {
223 				if ((width = wcwidth(ch)) > 0)
224 					cur_col += width;
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 		c->c_width = wcwidth(ch);
301 		/*
302 		 * If things are put in out of order, they will need sorting
303 		 * when it is flushed.
304 		 */
305 		if (cur_col < l->l_max_col)
306 			l->l_needs_sort = 1;
307 		else
308 			l->l_max_col = cur_col;
309 		if (c->c_width > 0)
310 			cur_col += c->c_width;
311 	}
312 	if (ferror(stdin))
313 		err(1, NULL);
314 	if (max_line == 0)
315 		exit(0);	/* no lines, so just exit */
316 
317 	/* goto the last line that had a character on it */
318 	for (; l->l_next; l = l->l_next)
319 		this_line++;
320 	flush_lines(this_line - nflushd_lines + extra_lines + 1);
321 
322 	/* make sure we leave things in a sane state */
323 	if (last_set != CS_NORMAL)
324 		PUTC('\017');
325 
326 	/* flush out the last few blank lines */
327 	nblank_lines = max_line - this_line;
328 	if (max_line & 1)
329 		nblank_lines++;
330 	else if (!nblank_lines)
331 		/* missing a \n on the last line? */
332 		nblank_lines = 2;
333 	flush_blanks();
334 	exit(0);
335 }
336 
337 static void
338 flush_lines(int nflush)
339 {
340 	LINE *l;
341 
342 	while (--nflush >= 0) {
343 		l = lines;
344 		lines = l->l_next;
345 		if (l->l_line) {
346 			flush_blanks();
347 			flush_line(l);
348 		}
349 		nblank_lines++;
350 		if (l->l_line)
351 			(void)free(l->l_line);
352 		free_line(l);
353 	}
354 	if (lines)
355 		lines->l_prev = NULL;
356 }
357 
358 /*
359  * Print a number of newline/half newlines.  If fine flag is set, nblank_lines
360  * is the number of half line feeds, otherwise it is the number of whole line
361  * feeds.
362  */
363 static void
364 flush_blanks(void)
365 {
366 	int half, i, nb;
367 
368 	half = 0;
369 	nb = nblank_lines;
370 	if (nb & 1) {
371 		if (fine)
372 			half = 1;
373 		else
374 			nb++;
375 	}
376 	nb /= 2;
377 	for (i = nb; --i >= 0;)
378 		PUTC('\n');
379 	if (half) {
380 		PUTC('\033');
381 		PUTC('\011');
382 		if (!nb)
383 			PUTC('\r');
384 	}
385 	nblank_lines = 0;
386 }
387 
388 /*
389  * Write a line to stdout taking care of space to tab conversion (-h flag)
390  * and character set shifts.
391  */
392 static void
393 flush_line(LINE *l)
394 {
395 	CHAR *c, *endc;
396 	int i, j, nchars, last_col, save, this_col, tot;
397 
398 	last_col = 0;
399 	nchars = l->l_line_len;
400 
401 	if (l->l_needs_sort) {
402 		static CHAR *sorted;
403 		static int count_size, *count, sorted_size;
404 
405 		/*
406 		 * Do an O(n) sort on l->l_line by column being careful to
407 		 * preserve the order of characters in the same column.
408 		 */
409 		if (l->l_lsize > sorted_size) {
410 			sorted_size = l->l_lsize;
411 			if ((sorted = realloc(sorted,
412 			    (unsigned)sizeof(CHAR) * sorted_size)) == NULL)
413 				err(1, (char *)NULL);
414 		}
415 		if (l->l_max_col >= count_size) {
416 			count_size = l->l_max_col + 1;
417 			if ((count = realloc(count,
418 			    (unsigned)sizeof(int) * count_size)) == NULL)
419 				err(1, (char *)NULL);
420 		}
421 		memset(count, 0, sizeof(int) * l->l_max_col + 1);
422 		for (i = nchars, c = l->l_line; --i >= 0; c++)
423 			count[c->c_column]++;
424 
425 		/*
426 		 * calculate running total (shifted down by 1) to use as
427 		 * indices into new line.
428 		 */
429 		for (tot = 0, i = 0; i <= l->l_max_col; i++) {
430 			save = count[i];
431 			count[i] = tot;
432 			tot += save;
433 		}
434 
435 		for (i = nchars, c = l->l_line; --i >= 0; c++)
436 			sorted[count[c->c_column]++] = *c;
437 		c = sorted;
438 	} else
439 		c = l->l_line;
440 	while (nchars > 0) {
441 		this_col = c->c_column;
442 		endc = c;
443 		do {
444 			++endc;
445 		} while (--nchars > 0 && this_col == endc->c_column);
446 
447 		/* if -b only print last character */
448 		if (no_backspaces) {
449 			c = endc - 1;
450 			if (nchars > 0 &&
451 			    this_col + c->c_width > endc->c_column)
452 				continue;
453 		}
454 
455 		if (this_col > last_col) {
456 			int nspace = this_col - last_col;
457 
458 			if (compress_spaces && nspace > 1) {
459 				while (1) {
460 					int tab_col, tab_size;
461 
462 					tab_col = (last_col + 8) & ~7;
463 					if (tab_col > this_col)
464 						break;
465 					tab_size = tab_col - last_col;
466 					if (tab_size == 1)
467 						PUTC(' ');
468 					else
469 						PUTC('\t');
470 					nspace -= tab_size;
471 					last_col = tab_col;
472 				}
473 			}
474 			while (--nspace >= 0)
475 				PUTC(' ');
476 			last_col = this_col;
477 		}
478 
479 		for (;;) {
480 			if (c->c_set != last_set) {
481 				switch (c->c_set) {
482 				case CS_NORMAL:
483 					PUTC('\017');
484 					break;
485 				case CS_ALTERNATE:
486 					PUTC('\016');
487 				}
488 				last_set = c->c_set;
489 			}
490 			PUTC(c->c_char);
491 			if ((c + 1) < endc)
492 				for (j = 0; j < c->c_width; j++)
493 					PUTC('\b');
494 			if (++c >= endc)
495 				break;
496 		}
497 		last_col += (c - 1)->c_width;
498 	}
499 }
500 
501 #define	NALLOC 64
502 
503 static LINE *line_freelist;
504 
505 static LINE *
506 alloc_line(void)
507 {
508 	LINE *l;
509 	int i;
510 
511 	if (!line_freelist) {
512 		if ((l = realloc(NULL, sizeof(LINE) * NALLOC)) == NULL)
513 			err(1, (char *)NULL);
514 		line_freelist = l;
515 		for (i = 1; i < NALLOC; i++, l++)
516 			l->l_next = l + 1;
517 		l->l_next = NULL;
518 	}
519 	l = line_freelist;
520 	line_freelist = l->l_next;
521 
522 	memset(l, 0, sizeof(LINE));
523 	return (l);
524 }
525 
526 static void
527 free_line(LINE *l)
528 {
529 
530 	l->l_next = line_freelist;
531 	line_freelist = l;
532 }
533 
534 static void
535 usage(void)
536 {
537 
538 	(void)fprintf(stderr, "usage: col [-bfhpx] [-l nline]\n");
539 	exit(1);
540 }
541 
542 static void
543 dowarn(int line)
544 {
545 
546 	warnx("warning: can't back up %s",
547 		line < 0 ? "past first line" : "-- line already flushed");
548 }
549