xref: /netbsd-src/usr.bin/fmt/fmt.c (revision 8b0f9554ff8762542c4defc4f70e1eb76fb508fa)
1 /*	$NetBSD: fmt.c,v 1.28 2007/12/15 19:44:50 perry Exp $	*/
2 
3 /*
4  * Copyright (c) 1980, 1993
5  *	The Regents of the University of California.  All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  * 3. Neither the name of the University nor the names of its contributors
16  *    may be used to endorse or promote products derived from this software
17  *    without specific prior written permission.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #include <sys/cdefs.h>
33 #ifndef lint
34 __COPYRIGHT("@(#) Copyright (c) 1980, 1993\n\
35 	The Regents of the University of California.  All rights reserved.\n");
36 #endif /* not lint */
37 
38 #ifndef lint
39 #if 0
40 static char sccsid[] = "@(#)fmt.c	8.1 (Berkeley) 7/20/93";
41 #endif
42 __RCSID("$NetBSD: fmt.c,v 1.28 2007/12/15 19:44:50 perry Exp $");
43 #endif /* not lint */
44 
45 #include <ctype.h>
46 #include <locale.h>
47 #include <stdio.h>
48 #include <stdlib.h>
49 #include <unistd.h>
50 #include <errno.h>
51 #include <err.h>
52 #include <limits.h>
53 #include <string.h>
54 #include "buffer.h"
55 
56 /*
57  * fmt -- format the concatenation of input files or standard input
58  * onto standard output.  Designed for use with Mail ~|
59  *
60  * Syntax : fmt [ goal [ max ] ] [ name ... ]
61  * Authors: Kurt Shoens (UCB) 12/7/78;
62  *          Liz Allen (UMCP) 2/24/83 [Addition of goal length concept].
63  */
64 
65 /* LIZ@UOM 6/18/85 --New variables goal_length and max_length */
66 #define GOAL_LENGTH 65
67 #define MAX_LENGTH 75
68 static size_t	goal_length;	/* Target or goal line length in output */
69 static size_t	max_length;	/* Max line length in output */
70 static size_t	pfx;		/* Current leading blank count */
71 static int	raw;		/* Don't treat mail specially */
72 static int	lineno;		/* Current input line */
73 static int	mark;		/* Last place we saw a head line */
74 static int	center;
75 static struct buffer outbuf;
76 
77 static const char	*headnames[] = {"To", "Subject", "Cc", 0};
78 
79 static void	usage(void) __dead;
80 static int 	getnum(const char *, const char *, size_t *, int);
81 static void	fmt(FILE *);
82 static int	ispref(const char *, const char *);
83 static void	leadin(void);
84 static void	oflush(void);
85 static void	pack(const char *, size_t);
86 static void	prefix(const struct buffer *, int);
87 static void	split(const char *, int);
88 static void	tabulate(struct buffer *);
89 
90 
91 int		ishead(const char *);
92 
93 /*
94  * Drive the whole formatter by managing input files.  Also,
95  * cause initialization of the output stuff and flush it out
96  * at the end.
97  */
98 
99 int
100 main(int argc, char **argv)
101 {
102 	FILE *fi;
103 	int errs = 0;
104 	int compat = 1;
105 	int c;
106 
107 	goal_length = GOAL_LENGTH;
108 	max_length = MAX_LENGTH;
109 	buf_init(&outbuf);
110 	lineno = 1;
111 	mark = -10;
112 
113 	setprogname(*argv);
114 	(void)setlocale(LC_ALL, "");
115 
116 	while ((c = getopt(argc, argv, "Cg:m:r")) != -1)
117 		switch (c) {
118 		case 'C':
119 			center++;
120 			break;
121 		case 'g':
122 			(void)getnum(optarg, "goal", &goal_length, 1);
123 			compat = 0;
124 			break;
125 		case 'm':
126 			(void)getnum(optarg, "max", &max_length, 1);
127 			compat = 0;
128 			break;
129 		case 'r':
130 			raw++;
131 			break;
132 		default:
133 			usage();
134 		}
135 
136 	argc -= optind;
137 	argv += optind;
138 
139 	/*
140 	 * compatibility with old usage.
141 	 */
142 	if (compat && argc > 0 && getnum(*argv, "goal", &goal_length, 0)) {
143 		argv++;
144 		argc--;
145 		if (argc > 0 && getnum(*argv, "max", &max_length, 0)) {
146 			argv++;
147 			argc--;
148 		}
149 	}
150 
151 	if (max_length <= goal_length) {
152 		errx(1, "Max length (%zu) must be greater than goal "
153 		    "length (%zu)", max_length, goal_length);
154 	}
155 	if (argc == 0) {
156 		fmt(stdin);
157 		oflush();
158 		return 0;
159 	}
160 	while (argc--) {
161 		if ((fi = fopen(*argv++, "r")) == NULL) {
162 			warn("Cannot open `%s'", *argv);
163 			errs++;
164 			continue;
165 		}
166 		fmt(fi);
167 		(void)fclose(fi);
168 	}
169 	oflush();
170 	buf_end(&outbuf);
171 	return errs;
172 }
173 
174 static void
175 usage(void)
176 {
177 	(void)fprintf(stderr,
178 	    "Usage: %s [-Cr] [-g <goal>] [-m <max>] [<files>..]\n"
179 	    "\t %s [-Cr] [<goal>] [<max>] [<files>]\n",
180 	    getprogname(), getprogname());
181 	exit(1);
182 }
183 
184 static int
185 getnum(const char *str, const char *what, size_t *res, int badnum)
186 {
187 	unsigned long ul;
188 	char *ep;
189 
190 	errno = 0;
191 	ul = strtoul(str, &ep, 0);
192         if (*str != '\0' && *ep == '\0') {
193 		 if ((errno == ERANGE && ul == ULONG_MAX) || ul > SIZE_T_MAX)
194 			errx(1, "%s number `%s' too big", what, str);
195 		*res = (size_t)ul;
196 		return 1;
197 	} else if (badnum)
198 		errx(1, "Bad %s number `%s'", what, str);
199 
200 	return 0;
201 }
202 
203 /*
204  * Read up characters from the passed input file, forming lines,
205  * doing ^H processing, expanding tabs, stripping trailing blanks,
206  * and sending each line down for analysis.
207  */
208 static void
209 fmt(FILE *fi)
210 {
211 	struct buffer lbuf, cbuf;
212 	char *cp, *cp2;
213 	int c, add_space;
214 	size_t len, col;
215 
216 	if (center) {
217 		for (;;) {
218 			cp = fgetln(fi, &len);
219 			if (!cp)
220 				return;
221 			cp2 = cp + len - 1;
222 			while (len-- && isspace((unsigned char)*cp))
223 				cp++;
224 			while (cp2 > cp && isspace((unsigned char)*cp2))
225 				cp2--;
226 			if (cp == cp2)
227 				(void)putchar('\n');
228 			col = cp2 - cp;
229 			if (goal_length > col)
230 				for (c = 0; c < (goal_length - col) / 2; c++)
231 					(void)putchar(' ');
232 			while (cp <= cp2)
233 				(void)putchar(*cp++);
234 			(void)putchar('\n');
235 		}
236 	}
237 
238 	buf_init(&lbuf);
239 	buf_init(&cbuf);
240 	c = getc(fi);
241 
242 	while (c != EOF) {
243 		/*
244 		 * Collect a line, doing ^H processing.
245 		 * Leave tabs for now.
246 		 */
247 		buf_reset(&lbuf);
248 		while (c != '\n' && c != EOF) {
249 			if (c == '\b') {
250 				(void)buf_unputc(&lbuf);
251 				c = getc(fi);
252 				continue;
253 			}
254 			if(!(isprint(c) || c == '\t' || c >= 160)) {
255 				c = getc(fi);
256 				continue;
257 			}
258 			buf_putc(&lbuf, c);
259 			c = getc(fi);
260 		}
261 		buf_putc(&lbuf, '\0');
262 		(void)buf_unputc(&lbuf);
263 		add_space = c != EOF;
264 
265 		/*
266 		 * Expand tabs on the way.
267 		 */
268 		col = 0;
269 		cp = lbuf.bptr;
270 		buf_reset(&cbuf);
271 		while ((c = *cp++) != '\0') {
272 			if (c != '\t') {
273 				col++;
274 				buf_putc(&cbuf, c);
275 				continue;
276 			}
277 			do {
278 				buf_putc(&cbuf, ' ');
279 				col++;
280 			} while ((col & 07) != 0);
281 		}
282 
283 		/*
284 		 * Swipe trailing blanks from the line.
285 		 */
286 		for (cp2 = cbuf.ptr - 1; cp2 >= cbuf.bptr && *cp2 == ' '; cp2--)
287 			continue;
288 		cbuf.ptr = cp2 + 1;
289 		buf_putc(&cbuf, '\0');
290 		(void)buf_unputc(&cbuf);
291 		prefix(&cbuf, add_space);
292 		if (c != EOF)
293 			c = getc(fi);
294 	}
295 	buf_end(&cbuf);
296 	buf_end(&lbuf);
297 }
298 
299 /*
300  * Take a line devoid of tabs and other garbage and determine its
301  * blank prefix.  If the indent changes, call for a linebreak.
302  * If the input line is blank, echo the blank line on the output.
303  * Finally, if the line minus the prefix is a mail header, try to keep
304  * it on a line by itself.
305  */
306 static void
307 prefix(const struct buffer *buf, int add_space)
308 {
309 	const char *cp;
310 	const char **hp;
311 	size_t np;
312 	int h;
313 
314 	if (buf->ptr == buf->bptr) {
315 		oflush();
316 		(void)putchar('\n');
317 		return;
318 	}
319 	for (cp = buf->bptr; *cp == ' '; cp++)
320 		continue;
321 	np = cp - buf->bptr;
322 
323 	/*
324 	 * The following horrible expression attempts to avoid linebreaks
325 	 * when the indent changes due to a paragraph.
326 	 */
327 	if (np != pfx && (np > pfx || abs((int)(pfx - np)) > 8))
328 		oflush();
329 	if (!raw) {
330 		if ((h = ishead(cp)) != 0) {
331 			oflush();
332 			mark = lineno;
333 		}
334 		if (lineno - mark < 3 && lineno - mark > 0)
335 			for (hp = &headnames[0]; *hp != NULL; hp++)
336 				if (ispref(*hp, cp)) {
337 					h = 1;
338 					oflush();
339 					break;
340 				}
341 		if (!h && (h = (*cp == '.')))
342 			oflush();
343 	} else
344 		h = 0;
345 	pfx = np;
346 	if (h) {
347 		pack(cp, (size_t)(buf->ptr - cp));
348 		oflush();
349 	} else
350 		split(cp, add_space);
351 	lineno++;
352 }
353 
354 /*
355  * Split up the passed line into output "words" which are
356  * maximal strings of non-blanks with the blank separation
357  * attached at the end.  Pass these words along to the output
358  * line packer.
359  */
360 static void
361 split(const char line[], int add_space)
362 {
363 	const char *cp;
364 	struct buffer word;
365 	size_t wlen;
366 
367 	buf_init(&word);
368 	cp = line;
369 	while (*cp) {
370 		buf_reset(&word);
371 		wlen = 0;
372 
373 		/*
374 		 * Collect a 'word,' allowing it to contain escaped white
375 		 * space.
376 		 */
377 		while (*cp && *cp != ' ') {
378 			if (*cp == '\\' && isspace((unsigned char)cp[1]))
379 				buf_putc(&word, *cp++);
380 			buf_putc(&word, *cp++);
381 			wlen++;
382 		}
383 
384 		/*
385 		 * Guarantee a space at end of line. Two spaces after end of
386 		 * sentence punctuation.
387 		 */
388 		if (*cp == '\0' && add_space) {
389 			buf_putc(&word, ' ');
390 			if (strchr(".:!", cp[-1]))
391 				buf_putc(&word, ' ');
392 		}
393 		while (*cp == ' ')
394 			buf_putc(&word, *cp++);
395 
396 		buf_putc(&word, '\0');
397 		(void)buf_unputc(&word);
398 
399 		pack(word.bptr, wlen);
400 	}
401 	buf_end(&word);
402 }
403 
404 /*
405  * Output section.
406  * Build up line images from the words passed in.  Prefix
407  * each line with correct number of blanks.
408  *
409  * At the bottom of this whole mess, leading tabs are reinserted.
410  */
411 
412 /*
413  * Pack a word onto the output line.  If this is the beginning of
414  * the line, push on the appropriately-sized string of blanks first.
415  * If the word won't fit on the current line, flush and begin a new
416  * line.  If the word is too long to fit all by itself on a line,
417  * just give it its own and hope for the best.
418  *
419  * LIZ@UOM 6/18/85 -- If the new word will fit in at less than the
420  *	goal length, take it.  If not, then check to see if the line
421  *	will be over the max length; if so put the word on the next
422  *	line.  If not, check to see if the line will be closer to the
423  *	goal length with or without the word and take it or put it on
424  *	the next line accordingly.
425  */
426 
427 static void
428 pack(const char *word, size_t wlen)
429 {
430 	const char *cp;
431 	size_t s, t;
432 
433 	if (outbuf.bptr == outbuf.ptr)
434 		leadin();
435 	/*
436 	 * LIZ@UOM 6/18/85 -- change condition to check goal_length; s is the
437 	 * length of the line before the word is added; t is now the length
438 	 * of the line after the word is added
439 	 */
440 	s = outbuf.ptr - outbuf.bptr;
441 	t = wlen + s;
442 	if ((t <= goal_length) || ((t <= max_length) &&
443 	    (s <= goal_length) && (t - goal_length <= goal_length - s))) {
444 		/*
445 		 * In like flint!
446 		 */
447 		for (cp = word; *cp;)
448 			buf_putc(&outbuf, *cp++);
449 		return;
450 	}
451 	if (s > pfx) {
452 		oflush();
453 		leadin();
454 	}
455 	for (cp = word; *cp;)
456 		buf_putc(&outbuf, *cp++);
457 }
458 
459 /*
460  * If there is anything on the current output line, send it on
461  * its way.  Reset outbuf.
462  */
463 static void
464 oflush(void)
465 {
466 	if (outbuf.bptr == outbuf.ptr)
467 		return;
468 	buf_putc(&outbuf, '\0');
469 	(void)buf_unputc(&outbuf);
470 	tabulate(&outbuf);
471 	buf_reset(&outbuf);
472 }
473 
474 /*
475  * Take the passed line buffer, insert leading tabs where possible, and
476  * output on standard output (finally).
477  */
478 static void
479 tabulate(struct buffer *buf)
480 {
481 	char *cp;
482 	size_t b, t;
483 
484 	/*
485 	 * Toss trailing blanks in the output line.
486 	 */
487 	for (cp = buf->ptr - 1; cp >= buf->bptr && *cp == ' '; cp--)
488 		continue;
489 	*++cp = '\0';
490 
491 	/*
492 	 * Count the leading blank space and tabulate.
493 	 */
494 	for (cp = buf->bptr; *cp == ' '; cp++)
495 		continue;
496 	b = cp - buf->bptr;
497 	t = b / 8;
498 	b = b % 8;
499 	if (t > 0)
500 		do
501 			(void)putchar('\t');
502 		while (--t);
503 	if (b > 0)
504 		do
505 			(void)putchar(' ');
506 		while (--b);
507 	while (*cp)
508 		(void)putchar(*cp++);
509 	(void)putchar('\n');
510 }
511 
512 /*
513  * Initialize the output line with the appropriate number of
514  * leading blanks.
515  */
516 static void
517 leadin(void)
518 {
519 	size_t b;
520 
521 	buf_reset(&outbuf);
522 
523 	for (b = 0; b < pfx; b++)
524 		buf_putc(&outbuf, ' ');
525 }
526 
527 /*
528  * Is s1 a prefix of s2??
529  */
530 static int
531 ispref(const char *s1, const char *s2)
532 {
533 
534 	while (*s1++ == *s2)
535 		continue;
536 	return *s1 == '\0';
537 }
538