xref: /freebsd/usr.bin/fmt/fmt.c (revision afe61c15161c324a7af299a9b8457aba5afc92db)
1 /*
2  * Copyright (c) 1980, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. All advertising materials mentioning features or use of this software
14  *    must display the following acknowledgement:
15  *	This product includes software developed by the University of
16  *	California, Berkeley and its contributors.
17  * 4. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  */
33 
34 #ifndef lint
35 static char copyright[] =
36 "@(#) Copyright (c) 1980, 1993\n\
37 	The Regents of the University of California.  All rights reserved.\n";
38 #endif /* not lint */
39 
40 #ifndef lint
41 static char sccsid[] = "@(#)fmt.c	8.1 (Berkeley) 7/20/93";
42 #endif /* not lint */
43 
44 #include <stdio.h>
45 #include <ctype.h>
46 
47 /*
48  * fmt -- format the concatenation of input files or standard input
49  * onto standard output.  Designed for use with Mail ~|
50  *
51  * Syntax : fmt [ goal [ max ] ] [ name ... ]
52  * Authors: Kurt Shoens (UCB) 12/7/78;
53  *          Liz Allen (UMCP) 2/24/83 [Addition of goal length concept].
54  */
55 
56 /* LIZ@UOM 6/18/85 -- Don't need LENGTH any more.
57  * #define	LENGTH	72		Max line length in output
58  */
59 #define	NOSTR	((char *) 0)	/* Null string pointer for lint */
60 
61 /* LIZ@UOM 6/18/85 --New variables goal_length and max_length */
62 #define GOAL_LENGTH 65
63 #define MAX_LENGTH 75
64 int	goal_length;		/* Target or goal line length in output */
65 int	max_length;		/* Max line length in output */
66 int	pfx;			/* Current leading blank count */
67 int	lineno;			/* Current input line */
68 int	mark;			/* Last place we saw a head line */
69 
70 char	*malloc();		/* for lint . . . */
71 char	*headnames[] = {"To", "Subject", "Cc", 0};
72 
73 /*
74  * Drive the whole formatter by managing input files.  Also,
75  * cause initialization of the output stuff and flush it out
76  * at the end.
77  */
78 
79 main(argc, argv)
80 	int argc;
81 	char **argv;
82 {
83 	register FILE *fi;
84 	register int errs = 0;
85 	int number;		/* LIZ@UOM 6/18/85 */
86 
87 	goal_length = GOAL_LENGTH;
88 	max_length = MAX_LENGTH;
89 	setout();
90 	lineno = 1;
91 	mark = -10;
92 	/*
93 	 * LIZ@UOM 6/18/85 -- Check for goal and max length arguments
94 	 */
95 	if (argc > 1 && (1 == (sscanf(argv[1], "%d", &number)))) {
96 		argv++;
97 		argc--;
98 		goal_length = number;
99 		if (argc > 1 && (1 == (sscanf(argv[1], "%d", &number)))) {
100 			argv++;
101 			argc--;
102 			max_length = number;
103 		}
104 	}
105 	if (max_length <= goal_length) {
106 		fprintf(stderr, "Max length must be greater than %s\n",
107 			"goal length");
108 		exit(1);
109 	}
110 	if (argc < 2) {
111 		fmt(stdin);
112 		oflush();
113 		exit(0);
114 	}
115 	while (--argc) {
116 		if ((fi = fopen(*++argv, "r")) == NULL) {
117 			perror(*argv);
118 			errs++;
119 			continue;
120 		}
121 		fmt(fi);
122 		fclose(fi);
123 	}
124 	oflush();
125 	exit(errs);
126 }
127 
128 /*
129  * Read up characters from the passed input file, forming lines,
130  * doing ^H processing, expanding tabs, stripping trailing blanks,
131  * and sending each line down for analysis.
132  */
133 fmt(fi)
134 	FILE *fi;
135 {
136 	char linebuf[BUFSIZ], canonb[BUFSIZ];
137 	register char *cp, *cp2;
138 	register int c, col;
139 
140 	c = getc(fi);
141 	while (c != EOF) {
142 		/*
143 		 * Collect a line, doing ^H processing.
144 		 * Leave tabs for now.
145 		 */
146 		cp = linebuf;
147 		while (c != '\n' && c != EOF && cp-linebuf < BUFSIZ-1) {
148 			if (c == '\b') {
149 				if (cp > linebuf)
150 					cp--;
151 				c = getc(fi);
152 				continue;
153 			}
154 			if ((c < ' ' || c >= 0177) && c != '\t') {
155 				c = getc(fi);
156 				continue;
157 			}
158 			*cp++ = c;
159 			c = getc(fi);
160 		}
161 		*cp = '\0';
162 
163 		/*
164 		 * Toss anything remaining on the input line.
165 		 */
166 		while (c != '\n' && c != EOF)
167 			c = getc(fi);
168 
169 		/*
170 		 * Expand tabs on the way to canonb.
171 		 */
172 		col = 0;
173 		cp = linebuf;
174 		cp2 = canonb;
175 		while (c = *cp++) {
176 			if (c != '\t') {
177 				col++;
178 				if (cp2-canonb < BUFSIZ-1)
179 					*cp2++ = c;
180 				continue;
181 			}
182 			do {
183 				if (cp2-canonb < BUFSIZ-1)
184 					*cp2++ = ' ';
185 				col++;
186 			} while ((col & 07) != 0);
187 		}
188 
189 		/*
190 		 * Swipe trailing blanks from the line.
191 		 */
192 		for (cp2--; cp2 >= canonb && *cp2 == ' '; cp2--)
193 			;
194 		*++cp2 = '\0';
195 		prefix(canonb);
196 		if (c != EOF)
197 			c = getc(fi);
198 	}
199 }
200 
201 /*
202  * Take a line devoid of tabs and other garbage and determine its
203  * blank prefix.  If the indent changes, call for a linebreak.
204  * If the input line is blank, echo the blank line on the output.
205  * Finally, if the line minus the prefix is a mail header, try to keep
206  * it on a line by itself.
207  */
208 prefix(line)
209 	char line[];
210 {
211 	register char *cp, **hp;
212 	register int np, h;
213 
214 	if (strlen(line) == 0) {
215 		oflush();
216 		putchar('\n');
217 		return;
218 	}
219 	for (cp = line; *cp == ' '; cp++)
220 		;
221 	np = cp - line;
222 
223 	/*
224 	 * The following horrible expression attempts to avoid linebreaks
225 	 * when the indent changes due to a paragraph.
226 	 */
227 	if (np != pfx && (np > pfx || abs(pfx-np) > 8))
228 		oflush();
229 	if (h = ishead(cp))
230 		oflush(), mark = lineno;
231 	if (lineno - mark < 3 && lineno - mark > 0)
232 		for (hp = &headnames[0]; *hp != (char *) 0; hp++)
233 			if (ispref(*hp, cp)) {
234 				h = 1;
235 				oflush();
236 				break;
237 			}
238 	if (!h && (h = (*cp == '.')))
239 		oflush();
240 	pfx = np;
241 	if (h)
242 		pack(cp, strlen(cp));
243 	else	split(cp);
244 	if (h)
245 		oflush();
246 	lineno++;
247 }
248 
249 /*
250  * Split up the passed line into output "words" which are
251  * maximal strings of non-blanks with the blank separation
252  * attached at the end.  Pass these words along to the output
253  * line packer.
254  */
255 split(line)
256 	char line[];
257 {
258 	register char *cp, *cp2;
259 	char word[BUFSIZ];
260 	int wordl;		/* LIZ@UOM 6/18/85 */
261 
262 	cp = line;
263 	while (*cp) {
264 		cp2 = word;
265 		wordl = 0;	/* LIZ@UOM 6/18/85 */
266 
267 		/*
268 		 * Collect a 'word,' allowing it to contain escaped white
269 		 * space.
270 		 */
271 		while (*cp && *cp != ' ') {
272 			if (*cp == '\\' && isspace(cp[1]))
273 				*cp2++ = *cp++;
274 			*cp2++ = *cp++;
275 			wordl++;/* LIZ@UOM 6/18/85 */
276 		}
277 
278 		/*
279 		 * Guarantee a space at end of line. Two spaces after end of
280 		 * sentence punctuation.
281 		 */
282 		if (*cp == '\0') {
283 			*cp2++ = ' ';
284 			if (index(".:!", cp[-1]))
285 				*cp2++ = ' ';
286 		}
287 		while (*cp == ' ')
288 			*cp2++ = *cp++;
289 		*cp2 = '\0';
290 		/*
291 		 * LIZ@UOM 6/18/85 pack(word);
292 		 */
293 		pack(word, wordl);
294 	}
295 }
296 
297 /*
298  * Output section.
299  * Build up line images from the words passed in.  Prefix
300  * each line with correct number of blanks.  The buffer "outbuf"
301  * contains the current partial line image, including prefixed blanks.
302  * "outp" points to the next available space therein.  When outp is NOSTR,
303  * there ain't nothing in there yet.  At the bottom of this whole mess,
304  * leading tabs are reinserted.
305  */
306 char	outbuf[BUFSIZ];			/* Sandbagged output line image */
307 char	*outp;				/* Pointer in above */
308 
309 /*
310  * Initialize the output section.
311  */
312 setout()
313 {
314 	outp = NOSTR;
315 }
316 
317 /*
318  * Pack a word onto the output line.  If this is the beginning of
319  * the line, push on the appropriately-sized string of blanks first.
320  * If the word won't fit on the current line, flush and begin a new
321  * line.  If the word is too long to fit all by itself on a line,
322  * just give it its own and hope for the best.
323  *
324  * LIZ@UOM 6/18/85 -- If the new word will fit in at less than the
325  *	goal length, take it.  If not, then check to see if the line
326  *	will be over the max length; if so put the word on the next
327  *	line.  If not, check to see if the line will be closer to the
328  *	goal length with or without the word and take it or put it on
329  *	the next line accordingly.
330  */
331 
332 /*
333  * LIZ@UOM 6/18/85 -- pass in the length of the word as well
334  * pack(word)
335  *	char word[];
336  */
337 pack(word,wl)
338 	char word[];
339 	int wl;
340 {
341 	register char *cp;
342 	register int s, t;
343 
344 	if (outp == NOSTR)
345 		leadin();
346 	/*
347 	 * LIZ@UOM 6/18/85 -- change condition to check goal_length; s is the
348 	 * length of the line before the word is added; t is now the length
349 	 * of the line after the word is added
350 	 *	t = strlen(word);
351 	 *	if (t+s <= LENGTH)
352 	 */
353 	s = outp - outbuf;
354 	t = wl + s;
355 	if ((t <= goal_length) ||
356 	    ((t <= max_length) && (t - goal_length <= goal_length - s))) {
357 		/*
358 		 * In like flint!
359 		 */
360 		for (cp = word; *cp; *outp++ = *cp++);
361 		return;
362 	}
363 	if (s > pfx) {
364 		oflush();
365 		leadin();
366 	}
367 	for (cp = word; *cp; *outp++ = *cp++);
368 }
369 
370 /*
371  * If there is anything on the current output line, send it on
372  * its way.  Set outp to NOSTR to indicate the absence of the current
373  * line prefix.
374  */
375 oflush()
376 {
377 	if (outp == NOSTR)
378 		return;
379 	*outp = '\0';
380 	tabulate(outbuf);
381 	outp = NOSTR;
382 }
383 
384 /*
385  * Take the passed line buffer, insert leading tabs where possible, and
386  * output on standard output (finally).
387  */
388 tabulate(line)
389 	char line[];
390 {
391 	register char *cp;
392 	register int b, t;
393 
394 	/*
395 	 * Toss trailing blanks in the output line.
396 	 */
397 	cp = line + strlen(line) - 1;
398 	while (cp >= line && *cp == ' ')
399 		cp--;
400 	*++cp = '\0';
401 
402 	/*
403 	 * Count the leading blank space and tabulate.
404 	 */
405 	for (cp = line; *cp == ' '; cp++)
406 		;
407 	b = cp-line;
408 	t = b >> 3;
409 	b &= 07;
410 	if (t > 0)
411 		do
412 			putc('\t', stdout);
413 		while (--t);
414 	if (b > 0)
415 		do
416 			putc(' ', stdout);
417 		while (--b);
418 	while (*cp)
419 		putc(*cp++, stdout);
420 	putc('\n', stdout);
421 }
422 
423 /*
424  * Initialize the output line with the appropriate number of
425  * leading blanks.
426  */
427 leadin()
428 {
429 	register int b;
430 	register char *cp;
431 
432 	for (b = 0, cp = outbuf; b < pfx; b++)
433 		*cp++ = ' ';
434 	outp = cp;
435 }
436 
437 /*
438  * Save a string in dynamic space.
439  * This little goodie is needed for
440  * a headline detector in head.c
441  */
442 char *
443 savestr(str)
444 	char str[];
445 {
446 	register char *top;
447 
448 	top = malloc(strlen(str) + 1);
449 	if (top == NOSTR) {
450 		fprintf(stderr, "fmt:  Ran out of memory\n");
451 		exit(1);
452 	}
453 	strcpy(top, str);
454 	return (top);
455 }
456 
457 /*
458  * Is s1 a prefix of s2??
459  */
460 ispref(s1, s2)
461 	register char *s1, *s2;
462 {
463 
464 	while (*s1++ == *s2)
465 		;
466 	return (*s1 == '\0');
467 }
468