xref: /freebsd/usr.bin/col/col.c (revision b7a1a0a5ff8895e6a5c9404d02357ac9e2eb8091)
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 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 static char sccsid[] = "@(#)col.c	8.3 (Berkeley) 4/2/94";
45 #endif /* not lint */
46 
47 #include <ctype.h>
48 #include <err.h>
49 #include <string.h>
50 #include <stdio.h>
51 #include <stdlib.h>
52 
53 #define	BS	'\b'		/* backspace */
54 #define	TAB	'\t'		/* tab */
55 #define	SPACE	' '		/* space */
56 #define	NL	'\n'		/* newline */
57 #define	CR	'\r'		/* carriage return */
58 #define	ESC	'\033'		/* escape */
59 #define	SI	'\017'		/* shift in to normal character set */
60 #define	SO	'\016'		/* shift out to alternate character set */
61 #define	VT	'\013'		/* vertical tab (aka reverse line feed) */
62 #define	RLF	'\007'		/* ESC-07 reverse line feed */
63 #define	RHLF	'\010'		/* ESC-010 reverse half-line feed */
64 #define	FHLF	'\011'		/* ESC-011 forward half-line feed */
65 
66 /* build up at least this many lines before flushing them out */
67 #define	BUFFER_MARGIN		32
68 
69 typedef char CSET;
70 
71 typedef struct char_str {
72 #define	CS_NORMAL	1
73 #define	CS_ALTERNATE	2
74 	short		c_column;	/* column character is in */
75 	CSET		c_set;		/* character set (currently only 2) */
76 	char		c_char;		/* character in question */
77 } CHAR;
78 
79 typedef struct line_str LINE;
80 struct line_str {
81 	CHAR	*l_line;		/* characters on the line */
82 	LINE	*l_prev;		/* previous line */
83 	LINE	*l_next;		/* next line */
84 	int	l_lsize;		/* allocated sizeof l_line */
85 	int	l_line_len;		/* strlen(l_line) */
86 	int	l_needs_sort;		/* set if chars went in out of order */
87 	int	l_max_col;		/* max column in the line */
88 };
89 
90 LINE   *alloc_line __P((void));
91 void	dowarn __P((int));
92 void	flush_line __P((LINE *));
93 void	flush_lines __P((int));
94 void	flush_blanks __P((void));
95 void	free_line __P((LINE *));
96 void	usage __P((void));
97 void	wrerr __P((void));
98 void   *xmalloc __P((void *, size_t));
99 
100 CSET	last_set;		/* char_set of last char printed */
101 LINE   *lines;
102 int	compress_spaces;	/* if doing space -> tab conversion */
103 int	fine;			/* if `fine' resolution (half lines) */
104 int	max_bufd_lines;		/* max # lines to keep in memory */
105 int	nblank_lines;		/* # blanks after last flushed line */
106 int	no_backspaces;		/* if not to output any backspaces */
107 
108 #define	PUTC(ch) \
109 	if (putchar(ch) == EOF) \
110 		wrerr();
111 
112 int
113 main(argc, argv)
114 	int argc;
115 	char **argv;
116 {
117 	int ch;
118 	CHAR *c;
119 	CSET cur_set;			/* current character set */
120 	LINE *l;			/* current line */
121 	int extra_lines;		/* # of lines above first line */
122 	int cur_col;			/* current column */
123 	int cur_line;			/* line number of current position */
124 	int max_line;			/* max value of cur_line */
125 	int this_line;			/* line l points to */
126 	int nflushd_lines;		/* number of lines that were flushed */
127 	int adjust, opt, warned;
128 
129 	max_bufd_lines = 128;
130 	compress_spaces = 1;		/* compress spaces into tabs */
131 	while ((opt = getopt(argc, argv, "bfhl:x")) != EOF)
132 		switch (opt) {
133 		case 'b':		/* do not output backspaces */
134 			no_backspaces = 1;
135 			break;
136 		case 'f':		/* allow half forward line feeds */
137 			fine = 1;
138 			break;
139 		case 'h':		/* compress spaces into tabs */
140 			compress_spaces = 1;
141 			break;
142 		case 'l':		/* buffered line count */
143 			if ((max_bufd_lines = atoi(optarg)) <= 0) {
144 				(void)fprintf(stderr,
145 				    "col: bad -l argument %s.\n", optarg);
146 				exit(1);
147 			}
148 			break;
149 		case 'x':		/* do not compress spaces into tabs */
150 			compress_spaces = 0;
151 			break;
152 		case '?':
153 		default:
154 			usage();
155 		}
156 
157 	if (optind != argc)
158 		usage();
159 
160 	/* this value is in half lines */
161 	max_bufd_lines *= 2;
162 
163 	adjust = cur_col = extra_lines = warned = 0;
164 	cur_line = max_line = nflushd_lines = this_line = 0;
165 	cur_set = last_set = CS_NORMAL;
166 	lines = l = alloc_line();
167 
168 	while ((ch = getchar()) != EOF) {
169 		if (!isgraph(ch)) {
170 			switch (ch) {
171 			case BS:		/* can't go back further */
172 				if (cur_col == 0)
173 					continue;
174 				--cur_col;
175 				continue;
176 			case CR:
177 				cur_col = 0;
178 				continue;
179 			case ESC:		/* just ignore EOF */
180 				switch(getchar()) {
181 				case RLF:
182 					cur_line -= 2;
183 					break;
184 				case RHLF:
185 					cur_line--;
186 					break;
187 				case FHLF:
188 					cur_line++;
189 					if (cur_line > max_line)
190 						max_line = cur_line;
191 				}
192 				continue;
193 			case NL:
194 				cur_line += 2;
195 				if (cur_line > max_line)
196 					max_line = cur_line;
197 				cur_col = 0;
198 				continue;
199 			case SPACE:
200 				++cur_col;
201 				continue;
202 			case SI:
203 				cur_set = CS_NORMAL;
204 				continue;
205 			case SO:
206 				cur_set = CS_ALTERNATE;
207 				continue;
208 			case TAB:		/* adjust column */
209 				cur_col |= 7;
210 				++cur_col;
211 				continue;
212 			case VT:
213 				cur_line -= 2;
214 				continue;
215 			}
216 			continue;
217 		}
218 
219 		/* Must stuff ch in a line - are we at the right one? */
220 		if (cur_line != this_line - adjust) {
221 			LINE *lnew;
222 			int nmove;
223 
224 			adjust = 0;
225 			nmove = cur_line - this_line;
226 			if (!fine) {
227 				/* round up to next line */
228 				if (cur_line & 1) {
229 					adjust = 1;
230 					nmove++;
231 				}
232 			}
233 			if (nmove < 0) {
234 				for (; nmove < 0 && l->l_prev; nmove++)
235 					l = l->l_prev;
236 				if (nmove) {
237 					if (nflushd_lines == 0) {
238 						/*
239 						 * Allow backup past first
240 						 * line if nothing has been
241 						 * flushed yet.
242 						 */
243 						for (; nmove < 0; nmove++) {
244 							lnew = alloc_line();
245 							l->l_prev = lnew;
246 							lnew->l_next = l;
247 							l = lines = lnew;
248 							extra_lines++;
249 						}
250 					} else {
251 						if (!warned++)
252 							dowarn(cur_line);
253 						cur_line -= nmove;
254 					}
255 				}
256 			} else {
257 				/* may need to allocate here */
258 				for (; nmove > 0 && l->l_next; nmove--)
259 					l = l->l_next;
260 				for (; nmove > 0; nmove--) {
261 					lnew = alloc_line();
262 					lnew->l_prev = l;
263 					l->l_next = lnew;
264 					l = lnew;
265 				}
266 			}
267 			this_line = cur_line + adjust;
268 			nmove = this_line - nflushd_lines;
269 			if (nmove >= max_bufd_lines + BUFFER_MARGIN) {
270 				nflushd_lines += nmove - max_bufd_lines;
271 				flush_lines(nmove - max_bufd_lines);
272 			}
273 		}
274 		/* grow line's buffer? */
275 		if (l->l_line_len + 1 >= l->l_lsize) {
276 			int need;
277 
278 			need = l->l_lsize ? l->l_lsize * 2 : 90;
279 			l->l_line = (CHAR *)xmalloc((void *) l->l_line,
280 			    (unsigned) need * sizeof(CHAR));
281 			l->l_lsize = need;
282 		}
283 		c = &l->l_line[l->l_line_len++];
284 		c->c_char = ch;
285 		c->c_set = cur_set;
286 		c->c_column = cur_col;
287 		/*
288 		 * If things are put in out of order, they will need sorting
289 		 * when it is flushed.
290 		 */
291 		if (cur_col < l->l_max_col)
292 			l->l_needs_sort = 1;
293 		else
294 			l->l_max_col = cur_col;
295 		cur_col++;
296 	}
297 	/* goto the last line that had a character on it */
298 	for (; l->l_next; l = l->l_next)
299 		this_line++;
300 	flush_lines(this_line - nflushd_lines + extra_lines + 1);
301 
302 	/* make sure we leave things in a sane state */
303 	if (last_set != CS_NORMAL)
304 		PUTC('\017');
305 
306 	/* flush out the last few blank lines */
307 	nblank_lines = max_line - this_line;
308 	if (max_line & 1)
309 		nblank_lines++;
310 	else if (!nblank_lines)
311 		/* missing a \n on the last line? */
312 		nblank_lines = 2;
313 	flush_blanks();
314 	exit(0);
315 }
316 
317 void
318 flush_lines(nflush)
319 	int nflush;
320 {
321 	LINE *l;
322 
323 	while (--nflush >= 0) {
324 		l = lines;
325 		lines = l->l_next;
326 		if (l->l_line) {
327 			flush_blanks();
328 			flush_line(l);
329 		}
330 		nblank_lines++;
331 		if (l->l_line)
332 			(void)free((void *)l->l_line);
333 		free_line(l);
334 	}
335 	if (lines)
336 		lines->l_prev = NULL;
337 }
338 
339 /*
340  * Print a number of newline/half newlines.  If fine flag is set, nblank_lines
341  * is the number of half line feeds, otherwise it is the number of whole line
342  * feeds.
343  */
344 void
345 flush_blanks()
346 {
347 	int half, i, nb;
348 
349 	half = 0;
350 	nb = nblank_lines;
351 	if (nb & 1) {
352 		if (fine)
353 			half = 1;
354 		else
355 			nb++;
356 	}
357 	nb /= 2;
358 	for (i = nb; --i >= 0;)
359 		PUTC('\n');
360 	if (half) {
361 		PUTC('\033');
362 		PUTC('9');
363 		if (!nb)
364 			PUTC('\r');
365 	}
366 	nblank_lines = 0;
367 }
368 
369 /*
370  * Write a line to stdout taking care of space to tab conversion (-h flag)
371  * and character set shifts.
372  */
373 void
374 flush_line(l)
375 	LINE *l;
376 {
377 	CHAR *c, *endc;
378 	int nchars, last_col, this_col;
379 
380 	last_col = 0;
381 	nchars = l->l_line_len;
382 
383 	if (l->l_needs_sort) {
384 		static CHAR *sorted;
385 		static int count_size, *count, i, save, sorted_size, tot;
386 
387 		/*
388 		 * Do an O(n) sort on l->l_line by column being careful to
389 		 * preserve the order of characters in the same column.
390 		 */
391 		if (l->l_lsize > sorted_size) {
392 			sorted_size = l->l_lsize;
393 			sorted = (CHAR *)xmalloc((void *)sorted,
394 			    (unsigned)sizeof(CHAR) * sorted_size);
395 		}
396 		if (l->l_max_col >= count_size) {
397 			count_size = l->l_max_col + 1;
398 			count = (int *)xmalloc((void *)count,
399 			    (unsigned)sizeof(int) * count_size);
400 		}
401 		memset((char *)count, 0, sizeof(int) * l->l_max_col + 1);
402 		for (i = nchars, c = l->l_line; --i >= 0; c++)
403 			count[c->c_column]++;
404 
405 		/*
406 		 * calculate running total (shifted down by 1) to use as
407 		 * indices into new line.
408 		 */
409 		for (tot = 0, i = 0; i <= l->l_max_col; i++) {
410 			save = count[i];
411 			count[i] = tot;
412 			tot += save;
413 		}
414 
415 		for (i = nchars, c = l->l_line; --i >= 0; c++)
416 			sorted[count[c->c_column]++] = *c;
417 		c = sorted;
418 	} else
419 		c = l->l_line;
420 	while (nchars > 0) {
421 		this_col = c->c_column;
422 		endc = c;
423 		do {
424 			++endc;
425 		} while (--nchars > 0 && this_col == endc->c_column);
426 
427 		/* if -b only print last character */
428 		if (no_backspaces)
429 			c = endc - 1;
430 
431 		if (this_col > last_col) {
432 			int nspace = this_col - last_col;
433 
434 			if (compress_spaces && nspace > 1) {
435 				int ntabs;
436 
437 				ntabs = this_col / 8 - last_col / 8;
438 				nspace -= ntabs * 8;
439 				while (--ntabs >= 0)
440 					PUTC('\t');
441 			}
442 			while (--nspace >= 0)
443 				PUTC(' ');
444 			last_col = this_col;
445 		}
446 		last_col++;
447 
448 		for (;;) {
449 			if (c->c_set != last_set) {
450 				switch (c->c_set) {
451 				case CS_NORMAL:
452 					PUTC('\017');
453 					break;
454 				case CS_ALTERNATE:
455 					PUTC('\016');
456 				}
457 				last_set = c->c_set;
458 			}
459 			PUTC(c->c_char);
460 			if (++c >= endc)
461 				break;
462 			PUTC('\b');
463 		}
464 	}
465 }
466 
467 #define	NALLOC 64
468 
469 static LINE *line_freelist;
470 
471 LINE *
472 alloc_line()
473 {
474 	LINE *l;
475 	int i;
476 
477 	if (!line_freelist) {
478 		l = (LINE *)xmalloc((void *)NULL, sizeof(LINE) * NALLOC);
479 		line_freelist = l;
480 		for (i = 1; i < NALLOC; i++, l++)
481 			l->l_next = l + 1;
482 		l->l_next = NULL;
483 	}
484 	l = line_freelist;
485 	line_freelist = l->l_next;
486 
487 	memset(l, 0, sizeof(LINE));
488 	return (l);
489 }
490 
491 void
492 free_line(l)
493 	LINE *l;
494 {
495 
496 	l->l_next = line_freelist;
497 	line_freelist = l;
498 }
499 
500 void *
501 xmalloc(p, size)
502 	void *p;
503 	size_t size;
504 {
505 
506 	if (!(p = (void *)realloc(p, size)))
507 		err(1, NULL);
508 	return (p);
509 }
510 
511 void
512 usage()
513 {
514 
515 	(void)fprintf(stderr, "usage: col [-bfx] [-l nline]\n");
516 	exit(1);
517 }
518 
519 void
520 wrerr()
521 {
522 
523 	(void)fprintf(stderr, "col: write error.\n");
524 	exit(1);
525 }
526 
527 void
528 dowarn(line)
529 	int line;
530 {
531 
532 	warnx("warning: can't back up %s",
533 		line < 0 ? "past first line" : "-- line already flushed");
534 }
535