xref: /illumos-gate/usr/src/cmd/man/makewhatis.c (revision eb9a1df2aeb866bf1de4494433b6d7e5fa07b3ae)
1 /*
2  * Copyright (c) 2002 John Rochester
3  * 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  *    in this position and unchanged.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. The name of the author may not be used to endorse or promote products
15  *    derived from this software without specific prior written permission
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
27  */
28 
29 /*
30  * Copyright 2012 Nexenta Systems, Inc. All rights reserved.
31  * Copyright 2014 Garrett D'Amore <garrett@damore.org>
32  */
33 
34 #include <sys/types.h>
35 #include <sys/stat.h>
36 #include <sys/param.h>
37 
38 #include <ctype.h>
39 #include <dirent.h>
40 #include <err.h>
41 #include <signal.h>
42 #include <stddef.h>
43 #include <stdio.h>
44 #include <stdlib.h>
45 #include <string.h>
46 #include <unistd.h>
47 
48 #include "man.h"
49 #include "stringlist.h"
50 
51 
52 /* Information collected about each man page in a section */
53 struct page_info {
54 	char	*filename;
55 	char	*name;
56 	char	*suffix;
57 	ino_t	inode;
58 };
59 
60 /* An expanding string */
61 struct sbuf {
62 	char	*content;	/* the start of the buffer */
63 	char	*end;		/* just past the end of the content */
64 	char	*last;		/* the last allocated character */
65 };
66 
67 /* Remove the last amount characters from the sbuf */
68 #define	sbuf_retract(sbuf, amount) ((sbuf)->end -= (amount))
69 /* Return the length of the sbuf content */
70 #define	sbuf_length(sbuf) ((sbuf)->end - (sbuf)->content)
71 
72 typedef char *edited_copy(char *from, char *to, int length);
73 
74 /*
75  * While the whatis line is being formed, it is stored in whatis_proto.
76  * When finished, it is reformatted into whatis_final and then appended
77  * to whatis_lines.
78  */
79 static struct sbuf	*whatis_proto;
80 static struct sbuf	*whatis_final;
81 static stringlist	*whatis_lines;	/* collected output lines */
82 
83 static char tempfile[MAXPATHLEN];	/* path of temporary file, if any */
84 
85 #define	MDOC_COMMANDS	"ArDvErEvFlLiNmPa"
86 
87 
88 /* Free a struct page_info and its content */
89 static void
90 free_page_info(struct page_info *info)
91 {
92 
93 	free(info->filename);
94 	free(info->name);
95 	free(info->suffix);
96 	free(info);
97 }
98 
99 /*
100  * Allocate and fill in a new struct page_info given the
101  * name of the man section directory and the dirent of the file.
102  * If the file is not a man page, return NULL.
103  */
104 static struct page_info *
105 new_page_info(char *dir, struct dirent *dirent)
106 {
107 	struct page_info *info;
108 	int		basename_length;
109 	char		*suffix;
110 	struct stat	st;
111 
112 	if ((info = malloc(sizeof (struct page_info))) == NULL)
113 		err(1, "malloc");
114 	basename_length = strlen(dirent->d_name);
115 	suffix = &dirent->d_name[basename_length];
116 	if (asprintf(&info->filename, "%s/%s", dir, dirent->d_name) == -1)
117 		err(1, "asprintf");
118 	for (;;) {
119 		if (--suffix == dirent->d_name || !isalnum(*suffix)) {
120 			if (*suffix == '.')
121 				break;
122 			free(info->filename);
123 			free(info);
124 			return (NULL);
125 		}
126 	}
127 	*suffix++ = '\0';
128 	info->name = strdup(dirent->d_name);
129 	info->suffix = strdup(suffix);
130 	if (stat(info->filename, &st) < 0) {
131 		warn("%s", info->filename);
132 		free_page_info(info);
133 		return (NULL);
134 	}
135 	if (!S_ISREG(st.st_mode)) {
136 		free_page_info(info);
137 		return (NULL);
138 	}
139 	info->inode = st.st_ino;
140 	return (info);
141 }
142 
143 /*
144  * Reset sbuf length to 0.
145  */
146 static void
147 sbuf_clear(struct sbuf *sbuf)
148 {
149 
150 	sbuf->end = sbuf->content;
151 }
152 
153 /*
154  * Allocate a new sbuf.
155  */
156 static struct sbuf *
157 new_sbuf(void)
158 {
159 	struct sbuf	*sbuf;
160 
161 	if ((sbuf = malloc(sizeof (struct sbuf))) == NULL)
162 		err(1, "malloc");
163 	if ((sbuf->content = (char *)malloc(LINE_ALLOC)) == NULL)
164 		err(1, "malloc");
165 	sbuf->last = sbuf->content + LINE_ALLOC - 1;
166 	sbuf_clear(sbuf);
167 
168 	return (sbuf);
169 }
170 
171 /*
172  * Ensure that there is enough room in the sbuf
173  * for nchars more characters.
174  */
175 static void
176 sbuf_need(struct sbuf *sbuf, int nchars)
177 {
178 	char *new_content;
179 	size_t size, cntsize;
180 	size_t grow = 128;
181 
182 	while (grow < nchars) {
183 		grow += 128;	/* we grow in chunks of 128 bytes */
184 	}
185 
186 	/* Grow if the buffer isn't big enough */
187 	if (sbuf->end + nchars > sbuf->last) {
188 		size = sbuf->last + 1 - sbuf->content;
189 		size += grow;
190 		cntsize = sbuf->end - sbuf->content;
191 
192 		if ((new_content = realloc(sbuf->content, size)) == NULL) {
193 			perror("realloc");
194 			if (tempfile[0] != '\0')
195 				(void) unlink(tempfile);
196 			exit(1);
197 		}
198 		sbuf->content = new_content;
199 		sbuf->end = new_content + cntsize;
200 		sbuf->last = new_content + size - 1;
201 	}
202 }
203 
204 /*
205  * Append a string of a given length to the sbuf.
206  */
207 static void
208 sbuf_append(struct sbuf *sbuf, const char *text, int length)
209 {
210 	if (length > 0) {
211 		sbuf_need(sbuf, length);
212 		(void) memcpy(sbuf->end, text, length);
213 		sbuf->end += length;
214 	}
215 }
216 
217 /*
218  * Append a null-terminated string to the sbuf.
219  */
220 static void
221 sbuf_append_str(struct sbuf *sbuf, char *text)
222 {
223 
224 	sbuf_append(sbuf, text, strlen(text));
225 }
226 
227 /*
228  * Append an edited null-terminated string to the sbuf.
229  */
230 static void
231 sbuf_append_edited(struct sbuf *sbuf, char *text, edited_copy copy)
232 {
233 	int	length;
234 
235 	if ((length = strlen(text)) > 0) {
236 		sbuf_need(sbuf, length);
237 		sbuf->end = copy(text, sbuf->end, length);
238 	}
239 }
240 
241 /*
242  * Strip any of a set of chars from the end of the sbuf.
243  */
244 static void
245 sbuf_strip(struct sbuf *sbuf, const char *set)
246 {
247 
248 	while (sbuf->end > sbuf->content && strchr(set, sbuf->end[-1]) != NULL)
249 		sbuf->end--;
250 }
251 
252 /*
253  * Return the null-terminated string built by the sbuf.
254  */
255 static char *
256 sbuf_content(struct sbuf *sbuf)
257 {
258 
259 	*sbuf->end = '\0';
260 	return (sbuf->content);
261 }
262 
263 /*
264  * Return true if no man page exists in the directory with
265  * any of the names in the stringlist.
266  */
267 static int
268 no_page_exists(char *dir, stringlist *names, char *suffix)
269 {
270 	char	path[MAXPATHLEN];
271 	char	*suffixes[] = { "", ".gz", ".bz2", NULL };
272 	size_t	i;
273 	int	j;
274 
275 	for (i = 0; i < names->sl_cur; i++) {
276 		for (j = 0; suffixes[j] != NULL; j++) {
277 			(void) snprintf(path, MAXPATHLEN, "%s/%s.%s%s",
278 			    dir, names->sl_str[i], suffix, suffixes[j]);
279 			if (access(path, F_OK) == 0) {
280 				return (0);
281 			}
282 		}
283 	}
284 	return (1);
285 }
286 
287 /* ARGSUSED sig */
288 static void
289 trap_signal(int sig)
290 {
291 
292 	if (tempfile[0] != '\0')
293 		(void) unlink(tempfile);
294 
295 	exit(1);
296 }
297 
298 /*
299  * Attempt to open an output file.
300  * Return NULL if unsuccessful.
301  */
302 static FILE *
303 open_output(char *name)
304 {
305 	FILE	*output;
306 
307 	whatis_lines = sl_init();
308 	(void) snprintf(tempfile, MAXPATHLEN, "%s.tmp", name);
309 	name = tempfile;
310 	if ((output = fopen(name, "w")) == NULL) {
311 		warn("%s", name);
312 		return (NULL);
313 	}
314 	return (output);
315 }
316 
317 static int
318 linesort(const void *a, const void *b)
319 {
320 
321 	return (strcmp((*(const char * const *)a), (*(const char * const *)b)));
322 }
323 
324 /*
325  * Write the unique sorted lines to the output file.
326  */
327 static void
328 finish_output(FILE *output, char *name)
329 {
330 	size_t	i;
331 	char	*prev = NULL;
332 
333 	qsort(whatis_lines->sl_str, whatis_lines->sl_cur, sizeof (char *),
334 	    linesort);
335 	for (i = 0; i < whatis_lines->sl_cur; i++) {
336 		char *line = whatis_lines->sl_str[i];
337 		if (i > 0 && strcmp(line, prev) == 0)
338 			continue;
339 		prev = line;
340 		(void) fputs(line, output);
341 		(void) putc('\n', output);
342 	}
343 	(void) fclose(output);
344 	sl_free(whatis_lines, 1);
345 	(void) rename(tempfile, name);
346 	(void) unlink(tempfile);
347 }
348 
349 static FILE *
350 open_whatis(char *mandir)
351 {
352 	char	filename[MAXPATHLEN];
353 
354 	(void) snprintf(filename, MAXPATHLEN, "%s/%s", mandir, WHATIS);
355 	return (open_output(filename));
356 }
357 
358 static void
359 finish_whatis(FILE *output, char *mandir)
360 {
361 	char	filename[MAXPATHLEN];
362 
363 	(void) snprintf(filename, MAXPATHLEN, "%s/%s", mandir, WHATIS);
364 	finish_output(output, filename);
365 }
366 
367 /*
368  * Remove trailing spaces from a string, returning a pointer to just
369  * beyond the new last character.
370  */
371 static char *
372 trim_rhs(char *str)
373 {
374 	char	*rhs;
375 
376 	rhs = &str[strlen(str)];
377 	while (--rhs > str && isspace(*rhs))
378 		;
379 	*++rhs = '\0';
380 	return (rhs);
381 }
382 
383 /*
384  * Return a pointer to the next non-space character in the string.
385  */
386 static char *
387 skip_spaces(char *s)
388 {
389 
390 	while (*s != '\0' && isspace(*s))
391 		s++;
392 
393 	return (s);
394 }
395 
396 /*
397  * Return whether the line is of one of the forms:
398  *	.Sh NAME
399  *	.Sh "NAME"
400  *	etc.
401  * assuming that section_start is ".Sh".
402  */
403 static int
404 name_section_line(char *line, const char *section_start)
405 {
406 	char		*rhs;
407 
408 	if (strncmp(line, section_start, 3) != 0)
409 		return (0);
410 	line = skip_spaces(line + 3);
411 	rhs = trim_rhs(line);
412 	if (*line == '"') {
413 		line++;
414 		if (*--rhs == '"')
415 			*rhs = '\0';
416 	}
417 	if (strcmp(line, "NAME") == 0)
418 		return (1);
419 
420 	return (0);
421 }
422 
423 /*
424  * Copy characters while removing the most common nroff/troff markup:
425  *	\(em, \(mi, \s[+-N], \&
426  *	\fF, \f(fo, \f[font]
427  *	\*s, \*(st, \*[stringvar]
428  */
429 static char *
430 de_nroff_copy(char *from, char *to, int fromlen)
431 {
432 	char	*from_end = &from[fromlen];
433 
434 	while (from < from_end) {
435 		switch (*from) {
436 		case '\\':
437 			switch (*++from) {
438 			case '(':
439 				if (strncmp(&from[1], "em", 2) == 0 ||
440 				    strncmp(&from[1], "mi", 2) == 0) {
441 					from += 3;
442 					continue;
443 				}
444 				break;
445 			case 's':
446 				if (*++from == '-')
447 					from++;
448 				while (isdigit(*from))
449 					from++;
450 				continue;
451 			case 'f':
452 			case '*':
453 				if (*++from == '(') {
454 					from += 3;
455 				} else if (*from == '[') {
456 					while (*++from != ']' &&
457 					    from < from_end)
458 						;
459 					from++;
460 				} else {
461 					from++;
462 				}
463 				continue;
464 			case '&':
465 				from++;
466 				continue;
467 			}
468 			break;
469 		}
470 		*to++ = *from++;
471 	}
472 	return (to);
473 }
474 
475 /*
476  * Append a string with the nroff formatting removed.
477  */
478 static void
479 add_nroff(char *text)
480 {
481 
482 	sbuf_append_edited(whatis_proto, text, de_nroff_copy);
483 }
484 
485 /*
486  * Appends "name(suffix), " to whatis_final
487  */
488 static void
489 add_whatis_name(char *name, char *suffix)
490 {
491 
492 	if (*name != '\0') {
493 		sbuf_append_str(whatis_final, name);
494 		sbuf_append(whatis_final, "(", 1);
495 		sbuf_append_str(whatis_final, suffix);
496 		sbuf_append(whatis_final, "), ", 3);
497 	}
498 }
499 
500 /*
501  * Processes an old-style man(7) line. This ignores commands with only
502  * a single number argument.
503  */
504 static void
505 process_man_line(char *line)
506 {
507 	char	*p;
508 
509 	if (*line == '.') {
510 		while (isalpha(*++line))
511 			;
512 		p = line = skip_spaces(line);
513 		while (*p != '\0') {
514 			if (!isdigit(*p))
515 				break;
516 			p++;
517 		}
518 		if (*p == '\0')
519 			return;
520 	} else
521 		line = skip_spaces(line);
522 	if (*line != '\0') {
523 		add_nroff(line);
524 		sbuf_append(whatis_proto, " ", 1);
525 	}
526 }
527 
528 /*
529  * Processes a new-style mdoc(7) line.
530  */
531 static void
532 process_mdoc_line(char *line)
533 {
534 	int	xref;
535 	int	arg = 0;
536 	char	*line_end = &line[strlen(line)];
537 	int	orig_length = sbuf_length(whatis_proto);
538 	char	*next;
539 
540 	if (*line == '\0')
541 		return;
542 	if (line[0] != '.' || !isupper(line[1]) || !islower(line[2])) {
543 		add_nroff(skip_spaces(line));
544 		sbuf_append(whatis_proto, " ", 1);
545 		return;
546 	}
547 	xref = strncmp(line, ".Xr", 3) == 0;
548 	line += 3;
549 	while ((line = skip_spaces(line)) < line_end) {
550 		if (*line == '"') {
551 			next = ++line;
552 			for (;;) {
553 				next = strchr(next, '"');
554 				if (next == NULL)
555 					break;
556 				(void) memmove(next, next + 1, strlen(next));
557 				line_end--;
558 				if (*next != '"')
559 					break;
560 				next++;
561 			}
562 		} else {
563 			next = strpbrk(line, " \t");
564 		}
565 		if (next != NULL)
566 			*next++ = '\0';
567 		else
568 			next = line_end;
569 		if (isupper(*line) && islower(line[1]) && line[2] == '\0') {
570 			if (strcmp(line, "Ns") == 0) {
571 				arg = 0;
572 				line = next;
573 				continue;
574 			}
575 			if (strstr(line, MDOC_COMMANDS) != NULL) {
576 				line = next;
577 				continue;
578 			}
579 		}
580 		if (arg > 0 && strchr(",.:;?!)]", *line) == 0) {
581 			if (xref) {
582 				sbuf_append(whatis_proto, "(", 1);
583 				add_nroff(line);
584 				sbuf_append(whatis_proto, ")", 1);
585 				xref = 0;
586 			} else {
587 				sbuf_append(whatis_proto, " ", 1);
588 			}
589 		}
590 		add_nroff(line);
591 		arg++;
592 		line = next;
593 	}
594 	if (sbuf_length(whatis_proto) > orig_length)
595 		sbuf_append(whatis_proto, " ", 1);
596 }
597 
598 /*
599  * Collect a list of comma-separated names from the text.
600  */
601 static void
602 collect_names(stringlist *names, char *text)
603 {
604 	char	*arg;
605 
606 	for (;;) {
607 		arg = text;
608 		text = strchr(text, ',');
609 		if (text != NULL)
610 			*text++ = '\0';
611 		(void) sl_add(names, arg);
612 		if (text == NULL)
613 			return;
614 		if (*text == ' ')
615 			text++;
616 	}
617 }
618 
619 enum { STATE_UNKNOWN, STATE_MANSTYLE, STATE_MDOCNAME, STATE_MDOCDESC };
620 
621 /*
622  * Process a man page source into a single whatis line and add it
623  * to whatis_lines.
624  */
625 static void
626 process_page(struct page_info *page, char *section_dir)
627 {
628 	FILE		*fp;
629 	stringlist	*names;
630 	char		*descr;
631 	int		state = STATE_UNKNOWN;
632 	size_t		i;
633 	char		*line = NULL;
634 	size_t		linecap = 0;
635 
636 	sbuf_clear(whatis_proto);
637 	if ((fp = fopen(page->filename, "r")) == NULL) {
638 		warn("%s", page->filename);
639 		return;
640 	}
641 	while (getline(&line, &linecap, fp) > 0) {
642 		/* Skip comments */
643 		if (strncmp(line, ".\\\"", 3) == 0)
644 			continue;
645 		switch (state) {
646 		/* Haven't reached the NAME section yet */
647 		case STATE_UNKNOWN:
648 			if (name_section_line(line, ".SH"))
649 				state = STATE_MANSTYLE;
650 			else if (name_section_line(line, ".Sh"))
651 				state = STATE_MDOCNAME;
652 			continue;
653 		/* Inside an old-style .SH NAME section */
654 		case STATE_MANSTYLE:
655 			if (strncmp(line, ".SH", 3) == 0 ||
656 			    strncmp(line, ".SS", 3) == 0)
657 				break;
658 			(void) trim_rhs(line);
659 			if (strcmp(line, ".") == 0)
660 				continue;
661 			if (strncmp(line, ".IX", 3) == 0) {
662 				line += 3;
663 				line = skip_spaces(line);
664 			}
665 			process_man_line(line);
666 			continue;
667 		/* Inside a new-style .Sh NAME section (the .Nm part) */
668 		case STATE_MDOCNAME:
669 			(void) trim_rhs(line);
670 			if (strncmp(line, ".Nm", 3) == 0) {
671 				process_mdoc_line(line);
672 				continue;
673 			} else {
674 				if (strcmp(line, ".") == 0)
675 					continue;
676 				sbuf_append(whatis_proto, "- ", 2);
677 				state = STATE_MDOCDESC;
678 			}
679 			/* FALLTHROUGH */
680 		/* Inside a new-style .Sh NAME section (after the .Nm-s) */
681 		case STATE_MDOCDESC:
682 			if (strncmp(line, ".Sh", 3) == 0)
683 				break;
684 			(void) trim_rhs(line);
685 			if (strcmp(line, ".") == 0)
686 				continue;
687 			process_mdoc_line(line);
688 			continue;
689 		}
690 		break;
691 	}
692 	(void) fclose(fp);
693 	sbuf_strip(whatis_proto, " \t.-");
694 	line = sbuf_content(whatis_proto);
695 	/*
696 	 * Line now contains the appropriate data, but without the
697 	 * proper indentation or the section appended to each name.
698 	 */
699 	descr = strstr(line, " - ");
700 	if (descr == NULL) {
701 		descr = strchr(line, ' ');
702 		if (descr == NULL)
703 			return;
704 		*descr++ = '\0';
705 	} else {
706 		*descr = '\0';
707 		descr += 3;
708 	}
709 	names = sl_init();
710 	collect_names(names, line);
711 	sbuf_clear(whatis_final);
712 	if (!sl_find(names, page->name) &&
713 	    no_page_exists(section_dir, names, page->suffix)) {
714 		/*
715 		 * Add the page name since that's the only
716 		 * thing that man(1) will find.
717 		 */
718 		add_whatis_name(page->name, page->suffix);
719 	}
720 	for (i = 0; i < names->sl_cur; i++)
721 		add_whatis_name(names->sl_str[i], page->suffix);
722 	sl_free(names, 0);
723 	/* Remove last ", " */
724 	sbuf_retract(whatis_final, 2);
725 	while (sbuf_length(whatis_final) < INDENT)
726 		sbuf_append(whatis_final, " ", 1);
727 	sbuf_append(whatis_final, " - ", 3);
728 	sbuf_append_str(whatis_final, skip_spaces(descr));
729 	(void) sl_add(whatis_lines, strdup(sbuf_content(whatis_final)));
730 }
731 
732 /*
733  * Sort pages first by inode number, then by name.
734  */
735 static int
736 pagesort(const void *a, const void *b)
737 {
738 	const struct page_info *p1 = *(struct page_info * const *) a;
739 	const struct page_info *p2 = *(struct page_info * const *) b;
740 
741 	if (p1->inode == p2->inode)
742 		return (strcmp(p1->name, p2->name));
743 
744 	return (p1->inode - p2->inode);
745 }
746 
747 /*
748  * Process a single man section.
749  */
750 static void
751 process_section(char *section_dir)
752 {
753 	struct dirent	**entries;
754 	int		nentries;
755 	struct page_info **pages;
756 	int		npages = 0;
757 	int		i;
758 	ino_t		prev_inode = 0;
759 
760 	/* Scan the man section directory for pages */
761 	nentries = scandir(section_dir, &entries, NULL, alphasort);
762 
763 	/* Collect information about man pages */
764 	pages = (struct page_info **)calloc(nentries,
765 	    sizeof (struct page_info *));
766 	for (i = 0; i < nentries; i++) {
767 		struct page_info *info = new_page_info(section_dir, entries[i]);
768 		if (info != NULL)
769 			pages[npages++] = info;
770 		free(entries[i]);
771 	}
772 	free(entries);
773 	qsort(pages, npages, sizeof (struct page_info *), pagesort);
774 
775 	/* Process each unique page */
776 	for (i = 0; i < npages; i++) {
777 		struct page_info *page = pages[i];
778 		if (page->inode != prev_inode) {
779 			prev_inode = page->inode;
780 			process_page(page, section_dir);
781 		}
782 		free_page_info(page);
783 	}
784 	free(pages);
785 }
786 
787 /*
788  * Return whether the directory entry is a man page section.
789  */
790 static int
791 select_sections(const struct dirent *entry)
792 {
793 	const char	*p = &entry->d_name[3];
794 
795 	if (strncmp(entry->d_name, "man", 3) != 0)
796 		return (0);
797 	while (*p != '\0') {
798 		if (!isalnum(*p++))
799 			return (0);
800 	}
801 	return (1);
802 }
803 
804 /*
805  * Process a single top-level man directory by finding all the
806  * sub-directories named man* and processing each one in turn.
807  */
808 void
809 mwpath(char *path)
810 {
811 	FILE		*fp = NULL;
812 	struct dirent	**entries;
813 	int		nsections;
814 	int		i;
815 
816 	(void) signal(SIGINT, trap_signal);
817 	(void) signal(SIGHUP, trap_signal);
818 	(void) signal(SIGQUIT, trap_signal);
819 	(void) signal(SIGTERM, trap_signal);
820 
821 	whatis_proto = new_sbuf();
822 	whatis_final = new_sbuf();
823 
824 	nsections = scandir(path, &entries, select_sections, alphasort);
825 	if ((fp = open_whatis(path)) == NULL)
826 		return;
827 	for (i = 0; i < nsections; i++) {
828 		char	section_dir[MAXPATHLEN];
829 
830 		(void) snprintf(section_dir, MAXPATHLEN, "%s/%s",
831 		    path, entries[i]->d_name);
832 		process_section(section_dir);
833 		free(entries[i]);
834 	}
835 	free(entries);
836 	finish_whatis(fp, path);
837 }
838