xref: /dragonfly/usr.bin/col/col.c (revision c3762235)
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. 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  * @(#) Copyright (c) 1990, 1993, 1994 The Regents of the University of California.  All rights reserved.
33  * @(#)col.c	8.5 (Berkeley) 5/4/95
34  * $FreeBSD: src/usr.bin/col/col.c,v 1.6.6.4 2001/08/02 01:27:12 obrien Exp $
35  */
36 
37 #include <ctype.h>
38 #include <err.h>
39 #include <string.h>
40 #include <stdio.h>
41 #include <stdlib.h>
42 #include <unistd.h>
43 #include <locale.h>
44 
45 #define	BS	'\b'		/* backspace */
46 #define	TAB	'\t'		/* tab */
47 #define	SPACE	' '		/* space */
48 #define	NL	'\n'		/* newline */
49 #define	CR	'\r'		/* carriage return */
50 #define	ESC	'\033'		/* escape */
51 #define	SI	'\017'		/* shift in to normal character set */
52 #define	SO	'\016'		/* shift out to alternate character set */
53 #define	VT	'\013'		/* vertical tab (aka reverse line feed) */
54 #define	RLF	'\007'		/* ESC-07 reverse line feed */
55 #define	RHLF	'\010'		/* ESC-010 reverse half-line feed */
56 #define	FHLF	'\011'		/* ESC-011 forward half-line feed */
57 
58 /* build up at least this many lines before flushing them out */
59 #define	BUFFER_MARGIN		32
60 
61 typedef char CSET;
62 
63 typedef struct char_str {
64 #define	CS_NORMAL	1
65 #define	CS_ALTERNATE	2
66 	short		c_column;	/* column character is in */
67 	CSET		c_set;		/* character set (currently only 2) */
68 	char		c_char;		/* character in question */
69 } CHAR;
70 
71 typedef struct line_str LINE;
72 struct line_str {
73 	CHAR	*l_line;		/* characters on the line */
74 	LINE	*l_prev;		/* previous line */
75 	LINE	*l_next;		/* next line */
76 	int	l_lsize;		/* allocated sizeof l_line */
77 	int	l_line_len;		/* strlen(l_line) */
78 	int	l_needs_sort;		/* set if chars went in out of order */
79 	int	l_max_col;		/* max column in the line */
80 };
81 
82 LINE   *alloc_line(void);
83 void	dowarn(int);
84 void	flush_line(LINE *);
85 void	flush_lines(int);
86 void	flush_blanks(void);
87 void	free_line(LINE *);
88 void	usage(void);
89 
90 CSET	last_set;		/* char_set of last char printed */
91 LINE   *lines;
92 int	compress_spaces;	/* if doing space -> tab conversion */
93 int	fine;			/* if `fine' resolution (half lines) */
94 int	max_bufd_lines;		/* max # lines to keep in memory */
95 int	nblank_lines;		/* # blanks after last flushed line */
96 int	no_backspaces;		/* if not to output any backspaces */
97 int	pass_unknown_seqs;	/* pass unknown control sequences */
98 
99 #define	PUTC(ch) \
100 	do {					\
101 		if (putchar(ch) == EOF)		\
102 			errx(1, "write error");	\
103 	} while (0)
104 
105 int
106 main(int argc, char **argv)
107 {
108 	int ch;
109 	CHAR *c;
110 	CSET cur_set;			/* current character set */
111 	LINE *l;			/* current line */
112 	int extra_lines;		/* # of lines above first line */
113 	int cur_col;			/* current column */
114 	int cur_line;			/* line number of current position */
115 	int max_line;			/* max value of cur_line */
116 	int this_line;			/* line l points to */
117 	int nflushd_lines;		/* number of lines that were flushed */
118 	int adjust, opt, warned;
119 
120 	(void)setlocale(LC_CTYPE, "");
121 
122 	max_bufd_lines = 128;
123 	compress_spaces = 1;		/* compress spaces into tabs */
124 	while ((opt = getopt(argc, argv, "bfhl:px")) != -1)
125 		switch (opt) {
126 		case 'b':		/* do not output backspaces */
127 			no_backspaces = 1;
128 			break;
129 		case 'f':		/* allow half forward line feeds */
130 			fine = 1;
131 			break;
132 		case 'h':		/* compress spaces into tabs */
133 			compress_spaces = 1;
134 			break;
135 		case 'l':		/* buffered line count */
136 			if ((max_bufd_lines = atoi(optarg)) <= 0)
137 				errx(1, "bad -l argument %s", optarg);
138 			break;
139 		case 'p':		/* pass unknown control sequences */
140 			pass_unknown_seqs = 1;
141 			break;
142 		case 'x':		/* do not compress spaces into tabs */
143 			compress_spaces = 0;
144 			break;
145 		case '?':
146 		default:
147 			usage();
148 		}
149 
150 	if (optind != argc)
151 		usage();
152 
153 	/* this value is in half lines */
154 	max_bufd_lines *= 2;
155 
156 	adjust = cur_col = extra_lines = warned = 0;
157 	cur_line = max_line = nflushd_lines = this_line = 0;
158 	cur_set = last_set = CS_NORMAL;
159 	lines = l = alloc_line();
160 
161 	while ((ch = getchar()) != EOF) {
162 		if (!isgraph(ch)) {
163 			switch (ch) {
164 			case BS:		/* can't go back further */
165 				if (cur_col == 0)
166 					continue;
167 				--cur_col;
168 				continue;
169 			case CR:
170 				cur_col = 0;
171 				continue;
172 			case ESC:		/* just ignore EOF */
173 				switch(getchar()) {
174 				case RLF:
175 					cur_line -= 2;
176 					break;
177 				case RHLF:
178 					cur_line--;
179 					break;
180 				case FHLF:
181 					cur_line++;
182 					if (cur_line > max_line)
183 						max_line = cur_line;
184 				}
185 				continue;
186 			case NL:
187 				cur_line += 2;
188 				if (cur_line > max_line)
189 					max_line = cur_line;
190 				cur_col = 0;
191 				continue;
192 			case SPACE:
193 				++cur_col;
194 				continue;
195 			case SI:
196 				cur_set = CS_NORMAL;
197 				continue;
198 			case SO:
199 				cur_set = CS_ALTERNATE;
200 				continue;
201 			case TAB:		/* adjust column */
202 				cur_col |= 7;
203 				++cur_col;
204 				continue;
205 			case VT:
206 				cur_line -= 2;
207 				continue;
208 			}
209 			if (!pass_unknown_seqs)
210 				continue;
211 		}
212 
213 		/* Must stuff ch in a line - are we at the right one? */
214 		if (cur_line != this_line - adjust) {
215 			LINE *lnew;
216 			int nmove;
217 
218 			adjust = 0;
219 			nmove = cur_line - this_line;
220 			if (!fine) {
221 				/* round up to next line */
222 				if (cur_line & 1) {
223 					adjust = 1;
224 					nmove++;
225 				}
226 			}
227 			if (nmove < 0) {
228 				for (; nmove < 0 && l->l_prev; nmove++)
229 					l = l->l_prev;
230 				if (nmove) {
231 					if (nflushd_lines == 0) {
232 						/*
233 						 * Allow backup past first
234 						 * line if nothing has been
235 						 * flushed yet.
236 						 */
237 						for (; nmove < 0; nmove++) {
238 							lnew = alloc_line();
239 							l->l_prev = lnew;
240 							lnew->l_next = l;
241 							l = lines = lnew;
242 							extra_lines++;
243 						}
244 					} else {
245 						if (!warned++)
246 							dowarn(cur_line);
247 						cur_line -= nmove;
248 					}
249 				}
250 			} else {
251 				/* may need to allocate here */
252 				for (; nmove > 0 && l->l_next; nmove--)
253 					l = l->l_next;
254 				for (; nmove > 0; nmove--) {
255 					lnew = alloc_line();
256 					lnew->l_prev = l;
257 					l->l_next = lnew;
258 					l = lnew;
259 				}
260 			}
261 			this_line = cur_line + adjust;
262 			nmove = this_line - nflushd_lines;
263 			if (nmove >= max_bufd_lines + BUFFER_MARGIN) {
264 				nflushd_lines += nmove - max_bufd_lines;
265 				flush_lines(nmove - max_bufd_lines);
266 			}
267 		}
268 		/* grow line's buffer? */
269 		if (l->l_line_len + 1 >= l->l_lsize) {
270 			int need;
271 
272 			need = l->l_lsize ? l->l_lsize * 2 : 90;
273 			if ((l->l_line = realloc(l->l_line,
274 			    (unsigned)need * sizeof(CHAR))) == NULL)
275 				err(1, NULL);
276 			l->l_lsize = need;
277 		}
278 		c = &l->l_line[l->l_line_len++];
279 		c->c_char = ch;
280 		c->c_set = cur_set;
281 		c->c_column = cur_col;
282 		/*
283 		 * If things are put in out of order, they will need sorting
284 		 * when it is flushed.
285 		 */
286 		if (cur_col < l->l_max_col)
287 			l->l_needs_sort = 1;
288 		else
289 			l->l_max_col = cur_col;
290 		cur_col++;
291 	}
292 	if (max_line == 0)
293 		exit(0);	/* no lines, so just exit */
294 
295 	/* goto the last line that had a character on it */
296 	for (; l->l_next; l = l->l_next)
297 		this_line++;
298 	flush_lines(this_line - nflushd_lines + extra_lines + 1);
299 
300 	/* make sure we leave things in a sane state */
301 	if (last_set != CS_NORMAL)
302 		PUTC('\017');
303 
304 	/* flush out the last few blank lines */
305 	nblank_lines = max_line - this_line;
306 	if (max_line & 1)
307 		nblank_lines++;
308 	else if (!nblank_lines)
309 		/* missing a \n on the last line? */
310 		nblank_lines = 2;
311 	flush_blanks();
312 	exit(0);
313 }
314 
315 void
316 flush_lines(int nflush)
317 {
318 	LINE *l;
319 
320 	while (--nflush >= 0) {
321 		l = lines;
322 		lines = l->l_next;
323 		if (l->l_line) {
324 			flush_blanks();
325 			flush_line(l);
326 		}
327 		nblank_lines++;
328 		if (l->l_line)
329 			(void)free(l->l_line);
330 		free_line(l);
331 	}
332 	if (lines)
333 		lines->l_prev = NULL;
334 }
335 
336 /*
337  * Print a number of newline/half newlines.  If fine flag is set, nblank_lines
338  * is the number of half line feeds, otherwise it is the number of whole line
339  * feeds.
340  */
341 void
342 flush_blanks(void)
343 {
344 	int half, i, nb;
345 
346 	half = 0;
347 	nb = nblank_lines;
348 	if (nb & 1) {
349 		if (fine)
350 			half = 1;
351 		else
352 			nb++;
353 	}
354 	nb /= 2;
355 	for (i = nb; --i >= 0;)
356 		PUTC('\n');
357 	if (half) {
358 		PUTC('\033');
359 		PUTC('9');
360 		if (!nb)
361 			PUTC('\r');
362 	}
363 	nblank_lines = 0;
364 }
365 
366 /*
367  * Write a line to stdout taking care of space to tab conversion (-h flag)
368  * and character set shifts.
369  */
370 void
371 flush_line(LINE *l)
372 {
373 	CHAR *c, *endc;
374 	int nchars, last_col, this_col;
375 
376 	last_col = 0;
377 	nchars = l->l_line_len;
378 
379 	if (l->l_needs_sort) {
380 		static CHAR *sorted;
381 		static int count_size, *count, i, save, sorted_size, tot;
382 
383 		/*
384 		 * Do an O(n) sort on l->l_line by column being careful to
385 		 * preserve the order of characters in the same column.
386 		 */
387 		if (l->l_lsize > sorted_size) {
388 			sorted_size = l->l_lsize;
389 			if ((sorted = realloc(sorted,
390 			    (unsigned)sizeof(CHAR) * sorted_size)) == NULL)
391 				err(1, NULL);
392 		}
393 		if (l->l_max_col >= count_size) {
394 			count_size = l->l_max_col + 1;
395 			if ((count = realloc(count,
396 			    (unsigned)sizeof(int) * count_size)) == NULL)
397 				err(1, NULL);
398 		}
399 		memset(count, 0, sizeof(int) * l->l_max_col + 1);
400 		for (i = nchars, c = l->l_line; --i >= 0; c++)
401 			count[c->c_column]++;
402 
403 		/*
404 		 * calculate running total (shifted down by 1) to use as
405 		 * indices into new line.
406 		 */
407 		for (tot = 0, i = 0; i <= l->l_max_col; i++) {
408 			save = count[i];
409 			count[i] = tot;
410 			tot += save;
411 		}
412 
413 		for (i = nchars, c = l->l_line; --i >= 0; c++)
414 			sorted[count[c->c_column]++] = *c;
415 		c = sorted;
416 	} else
417 		c = l->l_line;
418 	while (nchars > 0) {
419 		this_col = c->c_column;
420 		endc = c;
421 		do {
422 			++endc;
423 		} while (--nchars > 0 && this_col == endc->c_column);
424 
425 		/* if -b only print last character */
426 		if (no_backspaces)
427 			c = endc - 1;
428 
429 		if (this_col > last_col) {
430 			int nspace = this_col - last_col;
431 
432 			if (compress_spaces && nspace > 1) {
433 				while (1) {
434 					int tab_col, tab_size;
435 
436 					tab_col = (last_col + 8) & ~7;
437 					if (tab_col > this_col)
438 						break;
439 					tab_size = tab_col - last_col;
440 					if (tab_size == 1)
441 						PUTC(' ');
442 					else
443 						PUTC('\t');
444 					nspace -= tab_size;
445 					last_col = tab_col;
446 				}
447 			}
448 			while (--nspace >= 0)
449 				PUTC(' ');
450 			last_col = this_col;
451 		}
452 		last_col++;
453 
454 		for (;;) {
455 			if (c->c_set != last_set) {
456 				switch (c->c_set) {
457 				case CS_NORMAL:
458 					PUTC('\017');
459 					break;
460 				case CS_ALTERNATE:
461 					PUTC('\016');
462 				}
463 				last_set = c->c_set;
464 			}
465 			PUTC(c->c_char);
466 			if (++c >= endc)
467 				break;
468 			PUTC('\b');
469 		}
470 	}
471 }
472 
473 #define	NALLOC 64
474 
475 static LINE *line_freelist;
476 
477 LINE *
478 alloc_line(void)
479 {
480 	LINE *l;
481 	int i;
482 
483 	if (!line_freelist) {
484 		if ((l = realloc(NULL, sizeof(LINE) * NALLOC)) == NULL)
485 			err(1, NULL);
486 		line_freelist = l;
487 		for (i = 1; i < NALLOC; i++, l++)
488 			l->l_next = l + 1;
489 		l->l_next = NULL;
490 	}
491 	l = line_freelist;
492 	line_freelist = l->l_next;
493 
494 	memset(l, 0, sizeof(LINE));
495 	return (l);
496 }
497 
498 void
499 free_line(LINE *l)
500 {
501 
502 	l->l_next = line_freelist;
503 	line_freelist = l;
504 }
505 
506 void
507 usage(void)
508 {
509 
510 	(void)fprintf(stderr, "usage: col [-bfhpx] [-l nline]\n");
511 	exit(1);
512 }
513 
514 void
515 dowarn(int line)
516 {
517 
518 	warnx("warning: can't back up %s",
519 		line < 0 ? "past first line" : "-- line already flushed");
520 }
521