xref: /freebsd/usr.bin/col/col.c (revision 50d6b258b2511b2b1c3ee6195d9e9d17d49e04fd)
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 /* not lint */
42 
43 #ifndef lint
44 #if 0
45 static char sccsid[] = "@(#)col.c	8.5 (Berkeley) 5/4/95";
46 #endif
47 static const char rcsid[] =
48   "$FreeBSD$";
49 #endif /* not lint */
50 
51 #include <ctype.h>
52 #include <err.h>
53 #include <string.h>
54 #include <stdio.h>
55 #include <stdlib.h>
56 #include <unistd.h>
57 #include <locale.h>
58 
59 #define	BS	'\b'		/* backspace */
60 #define	TAB	'\t'		/* tab */
61 #define	SPACE	' '		/* space */
62 #define	NL	'\n'		/* newline */
63 #define	CR	'\r'		/* carriage return */
64 #define	ESC	'\033'		/* escape */
65 #define	SI	'\017'		/* shift in to normal character set */
66 #define	SO	'\016'		/* shift out to alternate character set */
67 #define	VT	'\013'		/* vertical tab (aka reverse line feed) */
68 #define	RLF	'\007'		/* ESC-07 reverse line feed */
69 #define	RHLF	'\010'		/* ESC-010 reverse half-line feed */
70 #define	FHLF	'\011'		/* ESC-011 forward half-line feed */
71 
72 /* build up at least this many lines before flushing them out */
73 #define	BUFFER_MARGIN		32
74 
75 typedef char CSET;
76 
77 typedef struct char_str {
78 #define	CS_NORMAL	1
79 #define	CS_ALTERNATE	2
80 	short		c_column;	/* column character is in */
81 	CSET		c_set;		/* character set (currently only 2) */
82 	char		c_char;		/* character in question */
83 } CHAR;
84 
85 typedef struct line_str LINE;
86 struct line_str {
87 	CHAR	*l_line;		/* characters on the line */
88 	LINE	*l_prev;		/* previous line */
89 	LINE	*l_next;		/* next line */
90 	int	l_lsize;		/* allocated sizeof l_line */
91 	int	l_line_len;		/* strlen(l_line) */
92 	int	l_needs_sort;		/* set if chars went in out of order */
93 	int	l_max_col;		/* max column in the line */
94 };
95 
96 LINE   *alloc_line __P((void));
97 void	dowarn __P((int));
98 void	flush_line __P((LINE *));
99 void	flush_lines __P((int));
100 void	flush_blanks __P((void));
101 void	free_line __P((LINE *));
102 int	main __P((int, char **));
103 void	usage __P((void));
104 void	wrerr __P((void));
105 void   *xmalloc __P((void *, size_t));
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 
115 #define	PUTC(ch) \
116 	do {				\
117 		if (putchar(ch) == EOF) \
118 			wrerr();	\
119 	} while (0)
120 
121 int
122 main(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:x")) != -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 'x':		/* do not compress spaces into tabs */
158 			compress_spaces = 0;
159 			break;
160 		case '?':
161 		default:
162 			usage();
163 		}
164 
165 	if (optind != argc)
166 		usage();
167 
168 	/* this value is in half lines */
169 	max_bufd_lines *= 2;
170 
171 	adjust = cur_col = extra_lines = warned = 0;
172 	cur_line = max_line = nflushd_lines = this_line = 0;
173 	cur_set = last_set = CS_NORMAL;
174 	lines = l = alloc_line();
175 
176 	while ((ch = getchar()) != EOF) {
177 		if (!isgraph(ch)) {
178 			switch (ch) {
179 			case BS:		/* can't go back further */
180 				if (cur_col == 0)
181 					continue;
182 				--cur_col;
183 				continue;
184 			case CR:
185 				cur_col = 0;
186 				continue;
187 			case ESC:		/* just ignore EOF */
188 				switch(getchar()) {
189 				case RLF:
190 					cur_line -= 2;
191 					break;
192 				case RHLF:
193 					cur_line--;
194 					break;
195 				case FHLF:
196 					cur_line++;
197 					if (cur_line > max_line)
198 						max_line = cur_line;
199 				}
200 				continue;
201 			case NL:
202 				cur_line += 2;
203 				if (cur_line > max_line)
204 					max_line = cur_line;
205 				cur_col = 0;
206 				continue;
207 			case SPACE:
208 				++cur_col;
209 				continue;
210 			case SI:
211 				cur_set = CS_NORMAL;
212 				continue;
213 			case SO:
214 				cur_set = CS_ALTERNATE;
215 				continue;
216 			case TAB:		/* adjust column */
217 				cur_col |= 7;
218 				++cur_col;
219 				continue;
220 			case VT:
221 				cur_line -= 2;
222 				continue;
223 			}
224 			continue;
225 		}
226 
227 		/* Must stuff ch in a line - are we at the right one? */
228 		if (cur_line != this_line - adjust) {
229 			LINE *lnew;
230 			int nmove;
231 
232 			adjust = 0;
233 			nmove = cur_line - this_line;
234 			if (!fine) {
235 				/* round up to next line */
236 				if (cur_line & 1) {
237 					adjust = 1;
238 					nmove++;
239 				}
240 			}
241 			if (nmove < 0) {
242 				for (; nmove < 0 && l->l_prev; nmove++)
243 					l = l->l_prev;
244 				if (nmove) {
245 					if (nflushd_lines == 0) {
246 						/*
247 						 * Allow backup past first
248 						 * line if nothing has been
249 						 * flushed yet.
250 						 */
251 						for (; nmove < 0; nmove++) {
252 							lnew = alloc_line();
253 							l->l_prev = lnew;
254 							lnew->l_next = l;
255 							l = lines = lnew;
256 							extra_lines++;
257 						}
258 					} else {
259 						if (!warned++)
260 							dowarn(cur_line);
261 						cur_line -= nmove;
262 					}
263 				}
264 			} else {
265 				/* may need to allocate here */
266 				for (; nmove > 0 && l->l_next; nmove--)
267 					l = l->l_next;
268 				for (; nmove > 0; nmove--) {
269 					lnew = alloc_line();
270 					lnew->l_prev = l;
271 					l->l_next = lnew;
272 					l = lnew;
273 				}
274 			}
275 			this_line = cur_line + adjust;
276 			nmove = this_line - nflushd_lines;
277 			if (nmove >= max_bufd_lines + BUFFER_MARGIN) {
278 				nflushd_lines += nmove - max_bufd_lines;
279 				flush_lines(nmove - max_bufd_lines);
280 			}
281 		}
282 		/* grow line's buffer? */
283 		if (l->l_line_len + 1 >= l->l_lsize) {
284 			int need;
285 
286 			need = l->l_lsize ? l->l_lsize * 2 : 90;
287 			l->l_line = (CHAR *)xmalloc((void *) l->l_line,
288 			    (unsigned) need * sizeof(CHAR));
289 			l->l_lsize = need;
290 		}
291 		c = &l->l_line[l->l_line_len++];
292 		c->c_char = ch;
293 		c->c_set = cur_set;
294 		c->c_column = cur_col;
295 		/*
296 		 * If things are put in out of order, they will need sorting
297 		 * when it is flushed.
298 		 */
299 		if (cur_col < l->l_max_col)
300 			l->l_needs_sort = 1;
301 		else
302 			l->l_max_col = cur_col;
303 		cur_col++;
304 	}
305 	if (max_line == 0)
306 		exit(0);	/* no lines, so just exit */
307 
308 	/* goto the last line that had a character on it */
309 	for (; l->l_next; l = l->l_next)
310 		this_line++;
311 	flush_lines(this_line - nflushd_lines + extra_lines + 1);
312 
313 	/* make sure we leave things in a sane state */
314 	if (last_set != CS_NORMAL)
315 		PUTC('\017');
316 
317 	/* flush out the last few blank lines */
318 	nblank_lines = max_line - this_line;
319 	if (max_line & 1)
320 		nblank_lines++;
321 	else if (!nblank_lines)
322 		/* missing a \n on the last line? */
323 		nblank_lines = 2;
324 	flush_blanks();
325 	exit(0);
326 }
327 
328 void
329 flush_lines(nflush)
330 	int nflush;
331 {
332 	LINE *l;
333 
334 	while (--nflush >= 0) {
335 		l = lines;
336 		lines = l->l_next;
337 		if (l->l_line) {
338 			flush_blanks();
339 			flush_line(l);
340 		}
341 		nblank_lines++;
342 		if (l->l_line)
343 			(void)free((void *)l->l_line);
344 		free_line(l);
345 	}
346 	if (lines)
347 		lines->l_prev = NULL;
348 }
349 
350 /*
351  * Print a number of newline/half newlines.  If fine flag is set, nblank_lines
352  * is the number of half line feeds, otherwise it is the number of whole line
353  * feeds.
354  */
355 void
356 flush_blanks()
357 {
358 	int half, i, nb;
359 
360 	half = 0;
361 	nb = nblank_lines;
362 	if (nb & 1) {
363 		if (fine)
364 			half = 1;
365 		else
366 			nb++;
367 	}
368 	nb /= 2;
369 	for (i = nb; --i >= 0;)
370 		PUTC('\n');
371 	if (half) {
372 		PUTC('\033');
373 		PUTC('9');
374 		if (!nb)
375 			PUTC('\r');
376 	}
377 	nblank_lines = 0;
378 }
379 
380 /*
381  * Write a line to stdout taking care of space to tab conversion (-h flag)
382  * and character set shifts.
383  */
384 void
385 flush_line(l)
386 	LINE *l;
387 {
388 	CHAR *c, *endc;
389 	int nchars, last_col, this_col;
390 
391 	last_col = 0;
392 	nchars = l->l_line_len;
393 
394 	if (l->l_needs_sort) {
395 		static CHAR *sorted;
396 		static int count_size, *count, i, save, sorted_size, tot;
397 
398 		/*
399 		 * Do an O(n) sort on l->l_line by column being careful to
400 		 * preserve the order of characters in the same column.
401 		 */
402 		if (l->l_lsize > sorted_size) {
403 			sorted_size = l->l_lsize;
404 			sorted = (CHAR *)xmalloc((void *)sorted,
405 			    (unsigned)sizeof(CHAR) * sorted_size);
406 		}
407 		if (l->l_max_col >= count_size) {
408 			count_size = l->l_max_col + 1;
409 			count = (int *)xmalloc((void *)count,
410 			    (unsigned)sizeof(int) * count_size);
411 		}
412 		memset((char *)count, 0, sizeof(int) * l->l_max_col + 1);
413 		for (i = nchars, c = l->l_line; --i >= 0; c++)
414 			count[c->c_column]++;
415 
416 		/*
417 		 * calculate running total (shifted down by 1) to use as
418 		 * indices into new line.
419 		 */
420 		for (tot = 0, i = 0; i <= l->l_max_col; i++) {
421 			save = count[i];
422 			count[i] = tot;
423 			tot += save;
424 		}
425 
426 		for (i = nchars, c = l->l_line; --i >= 0; c++)
427 			sorted[count[c->c_column]++] = *c;
428 		c = sorted;
429 	} else
430 		c = l->l_line;
431 	while (nchars > 0) {
432 		this_col = c->c_column;
433 		endc = c;
434 		do {
435 			++endc;
436 		} while (--nchars > 0 && this_col == endc->c_column);
437 
438 		/* if -b only print last character */
439 		if (no_backspaces)
440 			c = endc - 1;
441 
442 		if (this_col > last_col) {
443 			int nspace = this_col - last_col;
444 
445 			if (compress_spaces && nspace > 1) {
446 				while (1) {
447 					int tab_col, tab_size;;
448 
449 					tab_col = (last_col + 8) & ~7;
450 					if (tab_col > this_col)
451 						break;
452 					tab_size = tab_col - last_col;
453 					if (tab_size == 1)
454 						PUTC(' ');
455 					else
456 						PUTC('\t');
457 					nspace -= tab_size;
458 					last_col = tab_col;
459 				}
460 			}
461 			while (--nspace >= 0)
462 				PUTC(' ');
463 			last_col = this_col;
464 		}
465 		last_col++;
466 
467 		for (;;) {
468 			if (c->c_set != last_set) {
469 				switch (c->c_set) {
470 				case CS_NORMAL:
471 					PUTC('\017');
472 					break;
473 				case CS_ALTERNATE:
474 					PUTC('\016');
475 				}
476 				last_set = c->c_set;
477 			}
478 			PUTC(c->c_char);
479 			if (++c >= endc)
480 				break;
481 			PUTC('\b');
482 		}
483 	}
484 }
485 
486 #define	NALLOC 64
487 
488 static LINE *line_freelist;
489 
490 LINE *
491 alloc_line()
492 {
493 	LINE *l;
494 	int i;
495 
496 	if (!line_freelist) {
497 		l = (LINE *)xmalloc((void *)NULL, sizeof(LINE) * NALLOC);
498 		line_freelist = l;
499 		for (i = 1; i < NALLOC; i++, l++)
500 			l->l_next = l + 1;
501 		l->l_next = NULL;
502 	}
503 	l = line_freelist;
504 	line_freelist = l->l_next;
505 
506 	memset(l, 0, sizeof(LINE));
507 	return (l);
508 }
509 
510 void
511 free_line(l)
512 	LINE *l;
513 {
514 
515 	l->l_next = line_freelist;
516 	line_freelist = l;
517 }
518 
519 void *
520 xmalloc(p, size)
521 	void *p;
522 	size_t size;
523 {
524 
525 	if (!(p = (void *)realloc(p, size)))
526 		err(1, NULL);
527 	return (p);
528 }
529 
530 void
531 usage()
532 {
533 
534 	(void)fprintf(stderr, "usage: col [-bfhx] [-l nline]\n");
535 	exit(1);
536 }
537 
538 void
539 wrerr()
540 {
541 
542 	errx(1, "write error");
543 }
544 
545 void
546 dowarn(line)
547 	int line;
548 {
549 
550 	warnx("warning: can't back up %s",
551 		line < 0 ? "past first line" : "-- line already flushed");
552 }
553