xref: /freebsd/usr.bin/col/col.c (revision 953a3198a35204535cc9d450f04da982a4fea59b)
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 	do {				\
110 		if (putchar(ch) == EOF) \
111 			wrerr();	\
112 	} while (0)
113 
114 int
115 main(argc, argv)
116 	int argc;
117 	char **argv;
118 {
119 	int ch;
120 	CHAR *c;
121 	CSET cur_set;			/* current character set */
122 	LINE *l;			/* current line */
123 	int extra_lines;		/* # of lines above first line */
124 	int cur_col;			/* current column */
125 	int cur_line;			/* line number of current position */
126 	int max_line;			/* max value of cur_line */
127 	int this_line;			/* line l points to */
128 	int nflushd_lines;		/* number of lines that were flushed */
129 	int adjust, opt, warned;
130 
131 	max_bufd_lines = 128;
132 	compress_spaces = 1;		/* compress spaces into tabs */
133 	while ((opt = getopt(argc, argv, "bfhl:x")) != EOF)
134 		switch (opt) {
135 		case 'b':		/* do not output backspaces */
136 			no_backspaces = 1;
137 			break;
138 		case 'f':		/* allow half forward line feeds */
139 			fine = 1;
140 			break;
141 		case 'h':		/* compress spaces into tabs */
142 			compress_spaces = 1;
143 			break;
144 		case 'l':		/* buffered line count */
145 			if ((max_bufd_lines = atoi(optarg)) <= 0) {
146 				(void)fprintf(stderr,
147 				    "col: bad -l argument %s.\n", optarg);
148 				exit(1);
149 			}
150 			break;
151 		case 'x':		/* do not compress spaces into tabs */
152 			compress_spaces = 0;
153 			break;
154 		case '?':
155 		default:
156 			usage();
157 		}
158 
159 	if (optind != argc)
160 		usage();
161 
162 	/* this value is in half lines */
163 	max_bufd_lines *= 2;
164 
165 	adjust = cur_col = extra_lines = warned = 0;
166 	cur_line = max_line = nflushd_lines = this_line = 0;
167 	cur_set = last_set = CS_NORMAL;
168 	lines = l = alloc_line();
169 
170 	while ((ch = getchar()) != EOF) {
171 		if (!isgraph(ch)) {
172 			switch (ch) {
173 			case BS:		/* can't go back further */
174 				if (cur_col == 0)
175 					continue;
176 				--cur_col;
177 				continue;
178 			case CR:
179 				cur_col = 0;
180 				continue;
181 			case ESC:		/* just ignore EOF */
182 				switch(getchar()) {
183 				case RLF:
184 					cur_line -= 2;
185 					break;
186 				case RHLF:
187 					cur_line--;
188 					break;
189 				case FHLF:
190 					cur_line++;
191 					if (cur_line > max_line)
192 						max_line = cur_line;
193 				}
194 				continue;
195 			case NL:
196 				cur_line += 2;
197 				if (cur_line > max_line)
198 					max_line = cur_line;
199 				cur_col = 0;
200 				continue;
201 			case SPACE:
202 				++cur_col;
203 				continue;
204 			case SI:
205 				cur_set = CS_NORMAL;
206 				continue;
207 			case SO:
208 				cur_set = CS_ALTERNATE;
209 				continue;
210 			case TAB:		/* adjust column */
211 				cur_col |= 7;
212 				++cur_col;
213 				continue;
214 			case VT:
215 				cur_line -= 2;
216 				continue;
217 			}
218 			continue;
219 		}
220 
221 		/* Must stuff ch in a line - are we at the right one? */
222 		if (cur_line != this_line - adjust) {
223 			LINE *lnew;
224 			int nmove;
225 
226 			adjust = 0;
227 			nmove = cur_line - this_line;
228 			if (!fine) {
229 				/* round up to next line */
230 				if (cur_line & 1) {
231 					adjust = 1;
232 					nmove++;
233 				}
234 			}
235 			if (nmove < 0) {
236 				for (; nmove < 0 && l->l_prev; nmove++)
237 					l = l->l_prev;
238 				if (nmove) {
239 					if (nflushd_lines == 0) {
240 						/*
241 						 * Allow backup past first
242 						 * line if nothing has been
243 						 * flushed yet.
244 						 */
245 						for (; nmove < 0; nmove++) {
246 							lnew = alloc_line();
247 							l->l_prev = lnew;
248 							lnew->l_next = l;
249 							l = lines = lnew;
250 							extra_lines++;
251 						}
252 					} else {
253 						if (!warned++)
254 							dowarn(cur_line);
255 						cur_line -= nmove;
256 					}
257 				}
258 			} else {
259 				/* may need to allocate here */
260 				for (; nmove > 0 && l->l_next; nmove--)
261 					l = l->l_next;
262 				for (; nmove > 0; nmove--) {
263 					lnew = alloc_line();
264 					lnew->l_prev = l;
265 					l->l_next = lnew;
266 					l = lnew;
267 				}
268 			}
269 			this_line = cur_line + adjust;
270 			nmove = this_line - nflushd_lines;
271 			if (nmove >= max_bufd_lines + BUFFER_MARGIN) {
272 				nflushd_lines += nmove - max_bufd_lines;
273 				flush_lines(nmove - max_bufd_lines);
274 			}
275 		}
276 		/* grow line's buffer? */
277 		if (l->l_line_len + 1 >= l->l_lsize) {
278 			int need;
279 
280 			need = l->l_lsize ? l->l_lsize * 2 : 90;
281 			l->l_line = (CHAR *)xmalloc((void *) l->l_line,
282 			    (unsigned) need * sizeof(CHAR));
283 			l->l_lsize = need;
284 		}
285 		c = &l->l_line[l->l_line_len++];
286 		c->c_char = ch;
287 		c->c_set = cur_set;
288 		c->c_column = cur_col;
289 		/*
290 		 * If things are put in out of order, they will need sorting
291 		 * when it is flushed.
292 		 */
293 		if (cur_col < l->l_max_col)
294 			l->l_needs_sort = 1;
295 		else
296 			l->l_max_col = cur_col;
297 		cur_col++;
298 	}
299 	/* goto the last line that had a character on it */
300 	for (; l->l_next; l = l->l_next)
301 		this_line++;
302 	flush_lines(this_line - nflushd_lines + extra_lines + 1);
303 
304 	/* make sure we leave things in a sane state */
305 	if (last_set != CS_NORMAL)
306 		PUTC('\017');
307 
308 	/* flush out the last few blank lines */
309 	nblank_lines = max_line - this_line;
310 	if (max_line & 1)
311 		nblank_lines++;
312 	else if (!nblank_lines)
313 		/* missing a \n on the last line? */
314 		nblank_lines = 2;
315 	flush_blanks();
316 	exit(0);
317 }
318 
319 void
320 flush_lines(nflush)
321 	int nflush;
322 {
323 	LINE *l;
324 
325 	while (--nflush >= 0) {
326 		l = lines;
327 		lines = l->l_next;
328 		if (l->l_line) {
329 			flush_blanks();
330 			flush_line(l);
331 		}
332 		nblank_lines++;
333 		if (l->l_line)
334 			(void)free((void *)l->l_line);
335 		free_line(l);
336 	}
337 	if (lines)
338 		lines->l_prev = NULL;
339 }
340 
341 /*
342  * Print a number of newline/half newlines.  If fine flag is set, nblank_lines
343  * is the number of half line feeds, otherwise it is the number of whole line
344  * feeds.
345  */
346 void
347 flush_blanks()
348 {
349 	int half, i, nb;
350 
351 	half = 0;
352 	nb = nblank_lines;
353 	if (nb & 1) {
354 		if (fine)
355 			half = 1;
356 		else
357 			nb++;
358 	}
359 	nb /= 2;
360 	for (i = nb; --i >= 0;)
361 		PUTC('\n');
362 	if (half) {
363 		PUTC('\033');
364 		PUTC('9');
365 		if (!nb)
366 			PUTC('\r');
367 	}
368 	nblank_lines = 0;
369 }
370 
371 /*
372  * Write a line to stdout taking care of space to tab conversion (-h flag)
373  * and character set shifts.
374  */
375 void
376 flush_line(l)
377 	LINE *l;
378 {
379 	CHAR *c, *endc;
380 	int nchars, last_col, this_col;
381 
382 	last_col = 0;
383 	nchars = l->l_line_len;
384 
385 	if (l->l_needs_sort) {
386 		static CHAR *sorted;
387 		static int count_size, *count, i, save, sorted_size, tot;
388 
389 		/*
390 		 * Do an O(n) sort on l->l_line by column being careful to
391 		 * preserve the order of characters in the same column.
392 		 */
393 		if (l->l_lsize > sorted_size) {
394 			sorted_size = l->l_lsize;
395 			sorted = (CHAR *)xmalloc((void *)sorted,
396 			    (unsigned)sizeof(CHAR) * sorted_size);
397 		}
398 		if (l->l_max_col >= count_size) {
399 			count_size = l->l_max_col + 1;
400 			count = (int *)xmalloc((void *)count,
401 			    (unsigned)sizeof(int) * count_size);
402 		}
403 		memset((char *)count, 0, sizeof(int) * l->l_max_col + 1);
404 		for (i = nchars, c = l->l_line; --i >= 0; c++)
405 			count[c->c_column]++;
406 
407 		/*
408 		 * calculate running total (shifted down by 1) to use as
409 		 * indices into new line.
410 		 */
411 		for (tot = 0, i = 0; i <= l->l_max_col; i++) {
412 			save = count[i];
413 			count[i] = tot;
414 			tot += save;
415 		}
416 
417 		for (i = nchars, c = l->l_line; --i >= 0; c++)
418 			sorted[count[c->c_column]++] = *c;
419 		c = sorted;
420 	} else
421 		c = l->l_line;
422 	while (nchars > 0) {
423 		this_col = c->c_column;
424 		endc = c;
425 		do {
426 			++endc;
427 		} while (--nchars > 0 && this_col == endc->c_column);
428 
429 		/* if -b only print last character */
430 		if (no_backspaces)
431 			c = endc - 1;
432 
433 		if (this_col > last_col) {
434 			int nspace = this_col - last_col;
435 
436 			if (compress_spaces && nspace > 1) {
437 				while (1) {
438 					int tab_col, tab_size;;
439 
440 					tab_col = (last_col + 8) & ~7;
441 					if (tab_col > this_col)
442 						break;
443 					tab_size = tab_col - last_col;
444 					if (tab_size == 1)
445 						PUTC(' ');
446 					else
447 						PUTC('\t');
448 					nspace -= tab_size;
449 					last_col = tab_col;
450 				}
451 			}
452 			while (--nspace >= 0)
453 				PUTC(' ');
454 			last_col = this_col;
455 		}
456 		last_col++;
457 
458 		for (;;) {
459 			if (c->c_set != last_set) {
460 				switch (c->c_set) {
461 				case CS_NORMAL:
462 					PUTC('\017');
463 					break;
464 				case CS_ALTERNATE:
465 					PUTC('\016');
466 				}
467 				last_set = c->c_set;
468 			}
469 			PUTC(c->c_char);
470 			if (++c >= endc)
471 				break;
472 			PUTC('\b');
473 		}
474 	}
475 }
476 
477 #define	NALLOC 64
478 
479 static LINE *line_freelist;
480 
481 LINE *
482 alloc_line()
483 {
484 	LINE *l;
485 	int i;
486 
487 	if (!line_freelist) {
488 		l = (LINE *)xmalloc((void *)NULL, sizeof(LINE) * NALLOC);
489 		line_freelist = l;
490 		for (i = 1; i < NALLOC; i++, l++)
491 			l->l_next = l + 1;
492 		l->l_next = NULL;
493 	}
494 	l = line_freelist;
495 	line_freelist = l->l_next;
496 
497 	memset(l, 0, sizeof(LINE));
498 	return (l);
499 }
500 
501 void
502 free_line(l)
503 	LINE *l;
504 {
505 
506 	l->l_next = line_freelist;
507 	line_freelist = l;
508 }
509 
510 void *
511 xmalloc(p, size)
512 	void *p;
513 	size_t size;
514 {
515 
516 	if (!(p = (void *)realloc(p, size)))
517 		err(1, NULL);
518 	return (p);
519 }
520 
521 void
522 usage()
523 {
524 
525 	(void)fprintf(stderr, "usage: col [-bfx] [-l nline]\n");
526 	exit(1);
527 }
528 
529 void
530 wrerr()
531 {
532 
533 	(void)fprintf(stderr, "col: write error.\n");
534 	exit(1);
535 }
536 
537 void
538 dowarn(line)
539 	int line;
540 {
541 
542 	warnx("warning: can't back up %s",
543 		line < 0 ? "past first line" : "-- line already flushed");
544 }
545