xref: /freebsd/usr.bin/col/col.c (revision 380a989b3223d455375b4fae70fd0b9bdd43bafb)
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 static const char sccsid[] = "@(#)col.c	8.5 (Berkeley) 5/4/95";
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 #include <unistd.h>
53 #include <locale.h>
54 
55 #define	BS	'\b'		/* backspace */
56 #define	TAB	'\t'		/* tab */
57 #define	SPACE	' '		/* space */
58 #define	NL	'\n'		/* newline */
59 #define	CR	'\r'		/* carriage return */
60 #define	ESC	'\033'		/* escape */
61 #define	SI	'\017'		/* shift in to normal character set */
62 #define	SO	'\016'		/* shift out to alternate character set */
63 #define	VT	'\013'		/* vertical tab (aka reverse line feed) */
64 #define	RLF	'\007'		/* ESC-07 reverse line feed */
65 #define	RHLF	'\010'		/* ESC-010 reverse half-line feed */
66 #define	FHLF	'\011'		/* ESC-011 forward half-line feed */
67 
68 /* build up at least this many lines before flushing them out */
69 #define	BUFFER_MARGIN		32
70 
71 typedef char CSET;
72 
73 typedef struct char_str {
74 #define	CS_NORMAL	1
75 #define	CS_ALTERNATE	2
76 	short		c_column;	/* column character is in */
77 	CSET		c_set;		/* character set (currently only 2) */
78 	char		c_char;		/* character in question */
79 } CHAR;
80 
81 typedef struct line_str LINE;
82 struct line_str {
83 	CHAR	*l_line;		/* characters on the line */
84 	LINE	*l_prev;		/* previous line */
85 	LINE	*l_next;		/* next line */
86 	int	l_lsize;		/* allocated sizeof l_line */
87 	int	l_line_len;		/* strlen(l_line) */
88 	int	l_needs_sort;		/* set if chars went in out of order */
89 	int	l_max_col;		/* max column in the line */
90 };
91 
92 LINE   *alloc_line __P((void));
93 void	dowarn __P((int));
94 void	flush_line __P((LINE *));
95 void	flush_lines __P((int));
96 void	flush_blanks __P((void));
97 void	free_line __P((LINE *));
98 void	usage __P((void));
99 void	wrerr __P((void));
100 void   *xmalloc __P((void *, size_t));
101 
102 CSET	last_set;		/* char_set of last char printed */
103 LINE   *lines;
104 int	compress_spaces;	/* if doing space -> tab conversion */
105 int	fine;			/* if `fine' resolution (half lines) */
106 int	max_bufd_lines;		/* max # lines to keep in memory */
107 int	nblank_lines;		/* # blanks after last flushed line */
108 int	no_backspaces;		/* if not to output any backspaces */
109 
110 #define	PUTC(ch) \
111 	do {				\
112 		if (putchar(ch) == EOF) \
113 			wrerr();	\
114 	} while (0)
115 
116 int
117 main(argc, argv)
118 	int argc;
119 	char **argv;
120 {
121 	int 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;
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:x")) != -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 				(void)fprintf(stderr,
151 				    "col: bad -l argument %s.\n", optarg);
152 				exit(1);
153 			}
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 = getchar()) != EOF) {
175 		if (!isgraph(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(getchar()) {
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 			continue;
223 		}
224 
225 		/* Must stuff ch in a line - are we at the right one? */
226 		if (cur_line != this_line - adjust) {
227 			LINE *lnew;
228 			int nmove;
229 
230 			adjust = 0;
231 			nmove = cur_line - this_line;
232 			if (!fine) {
233 				/* round up to next line */
234 				if (cur_line & 1) {
235 					adjust = 1;
236 					nmove++;
237 				}
238 			}
239 			if (nmove < 0) {
240 				for (; nmove < 0 && l->l_prev; nmove++)
241 					l = l->l_prev;
242 				if (nmove) {
243 					if (nflushd_lines == 0) {
244 						/*
245 						 * Allow backup past first
246 						 * line if nothing has been
247 						 * flushed yet.
248 						 */
249 						for (; nmove < 0; nmove++) {
250 							lnew = alloc_line();
251 							l->l_prev = lnew;
252 							lnew->l_next = l;
253 							l = lines = lnew;
254 							extra_lines++;
255 						}
256 					} else {
257 						if (!warned++)
258 							dowarn(cur_line);
259 						cur_line -= nmove;
260 					}
261 				}
262 			} else {
263 				/* may need to allocate here */
264 				for (; nmove > 0 && l->l_next; nmove--)
265 					l = l->l_next;
266 				for (; nmove > 0; nmove--) {
267 					lnew = alloc_line();
268 					lnew->l_prev = l;
269 					l->l_next = lnew;
270 					l = lnew;
271 				}
272 			}
273 			this_line = cur_line + adjust;
274 			nmove = this_line - nflushd_lines;
275 			if (nmove >= max_bufd_lines + BUFFER_MARGIN) {
276 				nflushd_lines += nmove - max_bufd_lines;
277 				flush_lines(nmove - max_bufd_lines);
278 			}
279 		}
280 		/* grow line's buffer? */
281 		if (l->l_line_len + 1 >= l->l_lsize) {
282 			int need;
283 
284 			need = l->l_lsize ? l->l_lsize * 2 : 90;
285 			l->l_line = (CHAR *)xmalloc((void *) l->l_line,
286 			    (unsigned) need * sizeof(CHAR));
287 			l->l_lsize = need;
288 		}
289 		c = &l->l_line[l->l_line_len++];
290 		c->c_char = ch;
291 		c->c_set = cur_set;
292 		c->c_column = cur_col;
293 		/*
294 		 * If things are put in out of order, they will need sorting
295 		 * when it is flushed.
296 		 */
297 		if (cur_col < l->l_max_col)
298 			l->l_needs_sort = 1;
299 		else
300 			l->l_max_col = cur_col;
301 		cur_col++;
302 	}
303 	if (max_line == 0)
304 		exit(0);	/* no lines, so just exit */
305 
306 	/* goto the last line that had a character on it */
307 	for (; l->l_next; l = l->l_next)
308 		this_line++;
309 	flush_lines(this_line - nflushd_lines + extra_lines + 1);
310 
311 	/* make sure we leave things in a sane state */
312 	if (last_set != CS_NORMAL)
313 		PUTC('\017');
314 
315 	/* flush out the last few blank lines */
316 	nblank_lines = max_line - this_line;
317 	if (max_line & 1)
318 		nblank_lines++;
319 	else if (!nblank_lines)
320 		/* missing a \n on the last line? */
321 		nblank_lines = 2;
322 	flush_blanks();
323 	exit(0);
324 }
325 
326 void
327 flush_lines(nflush)
328 	int nflush;
329 {
330 	LINE *l;
331 
332 	while (--nflush >= 0) {
333 		l = lines;
334 		lines = l->l_next;
335 		if (l->l_line) {
336 			flush_blanks();
337 			flush_line(l);
338 		}
339 		nblank_lines++;
340 		if (l->l_line)
341 			(void)free((void *)l->l_line);
342 		free_line(l);
343 	}
344 	if (lines)
345 		lines->l_prev = NULL;
346 }
347 
348 /*
349  * Print a number of newline/half newlines.  If fine flag is set, nblank_lines
350  * is the number of half line feeds, otherwise it is the number of whole line
351  * feeds.
352  */
353 void
354 flush_blanks()
355 {
356 	int half, i, nb;
357 
358 	half = 0;
359 	nb = nblank_lines;
360 	if (nb & 1) {
361 		if (fine)
362 			half = 1;
363 		else
364 			nb++;
365 	}
366 	nb /= 2;
367 	for (i = nb; --i >= 0;)
368 		PUTC('\n');
369 	if (half) {
370 		PUTC('\033');
371 		PUTC('9');
372 		if (!nb)
373 			PUTC('\r');
374 	}
375 	nblank_lines = 0;
376 }
377 
378 /*
379  * Write a line to stdout taking care of space to tab conversion (-h flag)
380  * and character set shifts.
381  */
382 void
383 flush_line(l)
384 	LINE *l;
385 {
386 	CHAR *c, *endc;
387 	int nchars, last_col, this_col;
388 
389 	last_col = 0;
390 	nchars = l->l_line_len;
391 
392 	if (l->l_needs_sort) {
393 		static CHAR *sorted;
394 		static int count_size, *count, i, save, sorted_size, tot;
395 
396 		/*
397 		 * Do an O(n) sort on l->l_line by column being careful to
398 		 * preserve the order of characters in the same column.
399 		 */
400 		if (l->l_lsize > sorted_size) {
401 			sorted_size = l->l_lsize;
402 			sorted = (CHAR *)xmalloc((void *)sorted,
403 			    (unsigned)sizeof(CHAR) * sorted_size);
404 		}
405 		if (l->l_max_col >= count_size) {
406 			count_size = l->l_max_col + 1;
407 			count = (int *)xmalloc((void *)count,
408 			    (unsigned)sizeof(int) * count_size);
409 		}
410 		memset((char *)count, 0, sizeof(int) * l->l_max_col + 1);
411 		for (i = nchars, c = l->l_line; --i >= 0; c++)
412 			count[c->c_column]++;
413 
414 		/*
415 		 * calculate running total (shifted down by 1) to use as
416 		 * indices into new line.
417 		 */
418 		for (tot = 0, i = 0; i <= l->l_max_col; i++) {
419 			save = count[i];
420 			count[i] = tot;
421 			tot += save;
422 		}
423 
424 		for (i = nchars, c = l->l_line; --i >= 0; c++)
425 			sorted[count[c->c_column]++] = *c;
426 		c = sorted;
427 	} else
428 		c = l->l_line;
429 	while (nchars > 0) {
430 		this_col = c->c_column;
431 		endc = c;
432 		do {
433 			++endc;
434 		} while (--nchars > 0 && this_col == endc->c_column);
435 
436 		/* if -b only print last character */
437 		if (no_backspaces)
438 			c = endc - 1;
439 
440 		if (this_col > last_col) {
441 			int nspace = this_col - last_col;
442 
443 			if (compress_spaces && nspace > 1) {
444 				while (1) {
445 					int tab_col, tab_size;;
446 
447 					tab_col = (last_col + 8) & ~7;
448 					if (tab_col > this_col)
449 						break;
450 					tab_size = tab_col - last_col;
451 					if (tab_size == 1)
452 						PUTC(' ');
453 					else
454 						PUTC('\t');
455 					nspace -= tab_size;
456 					last_col = tab_col;
457 				}
458 			}
459 			while (--nspace >= 0)
460 				PUTC(' ');
461 			last_col = this_col;
462 		}
463 		last_col++;
464 
465 		for (;;) {
466 			if (c->c_set != last_set) {
467 				switch (c->c_set) {
468 				case CS_NORMAL:
469 					PUTC('\017');
470 					break;
471 				case CS_ALTERNATE:
472 					PUTC('\016');
473 				}
474 				last_set = c->c_set;
475 			}
476 			PUTC(c->c_char);
477 			if (++c >= endc)
478 				break;
479 			PUTC('\b');
480 		}
481 	}
482 }
483 
484 #define	NALLOC 64
485 
486 static LINE *line_freelist;
487 
488 LINE *
489 alloc_line()
490 {
491 	LINE *l;
492 	int i;
493 
494 	if (!line_freelist) {
495 		l = (LINE *)xmalloc((void *)NULL, sizeof(LINE) * NALLOC);
496 		line_freelist = l;
497 		for (i = 1; i < NALLOC; i++, l++)
498 			l->l_next = l + 1;
499 		l->l_next = NULL;
500 	}
501 	l = line_freelist;
502 	line_freelist = l->l_next;
503 
504 	memset(l, 0, sizeof(LINE));
505 	return (l);
506 }
507 
508 void
509 free_line(l)
510 	LINE *l;
511 {
512 
513 	l->l_next = line_freelist;
514 	line_freelist = l;
515 }
516 
517 void *
518 xmalloc(p, size)
519 	void *p;
520 	size_t size;
521 {
522 
523 	if (!(p = (void *)realloc(p, size)))
524 		err(1, NULL);
525 	return (p);
526 }
527 
528 void
529 usage()
530 {
531 
532 	(void)fprintf(stderr, "usage: col [-bfx] [-l nline]\n");
533 	exit(1);
534 }
535 
536 void
537 wrerr()
538 {
539 
540 	(void)fprintf(stderr, "col: write error.\n");
541 	exit(1);
542 }
543 
544 void
545 dowarn(line)
546 	int line;
547 {
548 
549 	warnx("warning: can't back up %s",
550 		line < 0 ? "past first line" : "-- line already flushed");
551 }
552