mansearch.c revision 322249 
1/*	$OpenBSD: mansearch.c,v 1.50 2016/07/09 15:23:36 schwarze Exp $ */
2/*
3 * Copyright (c) 2012 Kristaps Dzonsons <kristaps@bsd.lv>
4 * Copyright (c) 2013-2017 Ingo Schwarze <schwarze@openbsd.org>
5 *
6 * Permission to use, copy, modify, and distribute this software for any
7 * purpose with or without fee is hereby granted, provided that the above
8 * copyright notice and this permission notice appear in all copies.
9 *
10 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHORS DISCLAIM ALL WARRANTIES
11 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR
13 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17 */
18#include "config.h"
19
20#include <sys/mman.h>
21#include <sys/types.h>
22
23#include <assert.h>
24#if HAVE_ERR
25#include <err.h>
26#endif
27#include <errno.h>
28#include <fcntl.h>
29#include <glob.h>
30#include <limits.h>
31#include <regex.h>
32#include <stdio.h>
33#include <stdint.h>
34#include <stddef.h>
35#include <stdlib.h>
36#include <string.h>
37#include <unistd.h>
38
39#include "mandoc.h"
40#include "mandoc_aux.h"
41#include "mandoc_ohash.h"
42#include "manconf.h"
43#include "mansearch.h"
44#include "dbm.h"
45
46struct	expr {
47	/* Used for terms: */
48	struct dbm_match match;   /* Match type and expression. */
49	uint64_t	 bits;    /* Type mask. */
50	/* Used for OR and AND groups: */
51	struct expr	*next;    /* Next child in the parent group. */
52	struct expr	*child;   /* First child in this group. */
53	enum { EXPR_TERM, EXPR_OR, EXPR_AND } type;
54};
55
56const char *const mansearch_keynames[KEY_MAX] = {
57	"arch",	"sec",	"Xr",	"Ar",	"Fa",	"Fl",	"Dv",	"Fn",
58	"Ic",	"Pa",	"Cm",	"Li",	"Em",	"Cd",	"Va",	"Ft",
59	"Tn",	"Er",	"Ev",	"Sy",	"Sh",	"In",	"Ss",	"Ox",
60	"An",	"Mt",	"St",	"Bx",	"At",	"Nx",	"Fx",	"Lk",
61	"Ms",	"Bsx",	"Dx",	"Rs",	"Vt",	"Lb",	"Nm",	"Nd"
62};
63
64
65static	struct ohash	*manmerge(struct expr *, struct ohash *);
66static	struct ohash	*manmerge_term(struct expr *, struct ohash *);
67static	struct ohash	*manmerge_or(struct expr *, struct ohash *);
68static	struct ohash	*manmerge_and(struct expr *, struct ohash *);
69static	char		*buildnames(const struct dbm_page *);
70static	char		*buildoutput(size_t, struct dbm_page *);
71static	size_t		 lstlen(const char *, size_t);
72static	void		 lstcat(char *, size_t *, const char *, const char *);
73static	int		 lstmatch(const char *, const char *);
74static	struct expr	*exprcomp(const struct mansearch *,
75				int, char *[], int *);
76static	struct expr	*expr_and(const struct mansearch *,
77				int, char *[], int *);
78static	struct expr	*exprterm(const struct mansearch *,
79				int, char *[], int *);
80static	void		 exprfree(struct expr *);
81static	int		 manpage_compare(const void *, const void *);
82
83
84int
85mansearch(const struct mansearch *search,
86		const struct manpaths *paths,
87		int argc, char *argv[],
88		struct manpage **res, size_t *sz)
89{
90	char		 buf[PATH_MAX];
91	struct dbm_res	*rp;
92	struct expr	*e;
93	struct dbm_page	*page;
94	struct manpage	*mpage;
95	struct ohash	*htab;
96	size_t		 cur, i, maxres, outkey;
97	unsigned int	 slot;
98	int		 argi, chdir_status, getcwd_status, im;
99
100	argi = 0;
101	if ((e = exprcomp(search, argc, argv, &argi)) == NULL) {
102		*sz = 0;
103		return 0;
104	}
105
106	cur = maxres = 0;
107	if (res != NULL)
108		*res = NULL;
109
110	outkey = KEY_Nd;
111	if (search->outkey != NULL)
112		for (im = 0; im < KEY_MAX; im++)
113			if (0 == strcasecmp(search->outkey,
114			    mansearch_keynames[im])) {
115				outkey = im;
116				break;
117			}
118
119	/*
120	 * Remember the original working directory, if possible.
121	 * This will be needed if the second or a later directory
122	 * is given as a relative path.
123	 * Do not error out if the current directory is not
124	 * searchable: Maybe it won't be needed after all.
125	 */
126
127	if (getcwd(buf, PATH_MAX) == NULL) {
128		getcwd_status = 0;
129		(void)strlcpy(buf, strerror(errno), sizeof(buf));
130	} else
131		getcwd_status = 1;
132
133	/*
134	 * Loop over the directories (containing databases) for us to
135	 * search.
136	 * Don't let missing/bad databases/directories phase us.
137	 * In each, try to open the resident database and, if it opens,
138	 * scan it for our match expression.
139	 */
140
141	chdir_status = 0;
142	for (i = 0; i < paths->sz; i++) {
143		if (chdir_status && paths->paths[i][0] != '/') {
144			if ( ! getcwd_status) {
145				warnx("%s: getcwd: %s", paths->paths[i], buf);
146				continue;
147			} else if (chdir(buf) == -1) {
148				warn("%s", buf);
149				continue;
150			}
151		}
152		if (chdir(paths->paths[i]) == -1) {
153			warn("%s", paths->paths[i]);
154			continue;
155		}
156		chdir_status = 1;
157
158		if (dbm_open(MANDOC_DB) == -1) {
159			if (errno != ENOENT)
160				warn("%s/%s", paths->paths[i], MANDOC_DB);
161			continue;
162		}
163
164		if ((htab = manmerge(e, NULL)) == NULL) {
165			dbm_close();
166			continue;
167		}
168
169		for (rp = ohash_first(htab, &slot); rp != NULL;
170		    rp = ohash_next(htab, &slot)) {
171			page = dbm_page_get(rp->page);
172
173			if (lstmatch(search->sec, page->sect) == 0 ||
174			    lstmatch(search->arch, page->arch) == 0)
175				continue;
176
177			if (res == NULL) {
178				cur = 1;
179				break;
180			}
181			if (cur + 1 > maxres) {
182				maxres += 1024;
183				*res = mandoc_reallocarray(*res,
184				    maxres, sizeof(**res));
185			}
186			mpage = *res + cur;
187			mandoc_asprintf(&mpage->file, "%s/%s",
188			    paths->paths[i], page->file + 1);
189			mpage->names = buildnames(page);
190			mpage->output = buildoutput(outkey, page);
191			mpage->ipath = i;
192			mpage->bits = rp->bits;
193			mpage->sec = *page->sect - '0';
194			if (mpage->sec < 0 || mpage->sec > 9)
195				mpage->sec = 10;
196			mpage->form = *page->file;
197			free(rp);
198			cur++;
199		}
200		ohash_delete(htab);
201		free(htab);
202		dbm_close();
203
204		/*
205		 * In man(1) mode, prefer matches in earlier trees
206		 * over matches in later trees.
207		 */
208
209		if (cur && search->firstmatch)
210			break;
211	}
212	if (res != NULL)
213		qsort(*res, cur, sizeof(struct manpage), manpage_compare);
214	if (chdir_status && getcwd_status && chdir(buf) == -1)
215		warn("%s", buf);
216	exprfree(e);
217	*sz = cur;
218	return res != NULL || cur;
219}
220
221/*
222 * Merge the results for the expression tree rooted at e
223 * into the the result list htab.
224 */
225static struct ohash *
226manmerge(struct expr *e, struct ohash *htab)
227{
228	switch (e->type) {
229	case EXPR_TERM:
230		return manmerge_term(e, htab);
231	case EXPR_OR:
232		return manmerge_or(e->child, htab);
233	case EXPR_AND:
234		return manmerge_and(e->child, htab);
235	default:
236		abort();
237	}
238}
239
240static struct ohash *
241manmerge_term(struct expr *e, struct ohash *htab)
242{
243	struct dbm_res	 res, *rp;
244	uint64_t	 ib;
245	unsigned int	 slot;
246	int		 im;
247
248	if (htab == NULL) {
249		htab = mandoc_malloc(sizeof(*htab));
250		mandoc_ohash_init(htab, 4, offsetof(struct dbm_res, page));
251	}
252
253	for (im = 0, ib = 1; im < KEY_MAX; im++, ib <<= 1) {
254		if ((e->bits & ib) == 0)
255			continue;
256
257		switch (ib) {
258		case TYPE_arch:
259			dbm_page_byarch(&e->match);
260			break;
261		case TYPE_sec:
262			dbm_page_bysect(&e->match);
263			break;
264		case TYPE_Nm:
265			dbm_page_byname(&e->match);
266			break;
267		case TYPE_Nd:
268			dbm_page_bydesc(&e->match);
269			break;
270		default:
271			dbm_page_bymacro(im - 2, &e->match);
272			break;
273		}
274
275		/*
276		 * When hashing for deduplication, use the unique
277		 * page ID itself instead of a hash function;
278		 * that is quite efficient.
279		 */
280
281		for (;;) {
282			res = dbm_page_next();
283			if (res.page == -1)
284				break;
285			slot = ohash_lookup_memory(htab,
286			    (char *)&res, sizeof(res.page), res.page);
287			if ((rp = ohash_find(htab, slot)) != NULL) {
288				rp->bits |= res.bits;
289				continue;
290			}
291			rp = mandoc_malloc(sizeof(*rp));
292			*rp = res;
293			ohash_insert(htab, slot, rp);
294		}
295	}
296	return htab;
297}
298
299static struct ohash *
300manmerge_or(struct expr *e, struct ohash *htab)
301{
302	while (e != NULL) {
303		htab = manmerge(e, htab);
304		e = e->next;
305	}
306	return htab;
307}
308
309static struct ohash *
310manmerge_and(struct expr *e, struct ohash *htab)
311{
312	struct ohash	*hand, *h1, *h2;
313	struct dbm_res	*res;
314	unsigned int	 slot1, slot2;
315
316	/* Evaluate the first term of the AND clause. */
317
318	hand = manmerge(e, NULL);
319
320	while ((e = e->next) != NULL) {
321
322		/* Evaluate the next term and prepare for ANDing. */
323
324		h2 = manmerge(e, NULL);
325		if (ohash_entries(h2) < ohash_entries(hand)) {
326			h1 = h2;
327			h2 = hand;
328		} else
329			h1 = hand;
330		hand = mandoc_malloc(sizeof(*hand));
331		mandoc_ohash_init(hand, 4, offsetof(struct dbm_res, page));
332
333		/* Keep all pages that are in both result sets. */
334
335		for (res = ohash_first(h1, &slot1); res != NULL;
336		    res = ohash_next(h1, &slot1)) {
337			if (ohash_find(h2, ohash_lookup_memory(h2,
338			    (char *)res, sizeof(res->page),
339			    res->page)) == NULL)
340				free(res);
341			else
342				ohash_insert(hand, ohash_lookup_memory(hand,
343				    (char *)res, sizeof(res->page),
344				    res->page), res);
345		}
346
347		/* Discard the merged results. */
348
349		for (res = ohash_first(h2, &slot2); res != NULL;
350		    res = ohash_next(h2, &slot2))
351			free(res);
352		ohash_delete(h2);
353		free(h2);
354		ohash_delete(h1);
355		free(h1);
356	}
357
358	/* Merge the result of the AND into htab. */
359
360	if (htab == NULL)
361		return hand;
362
363	for (res = ohash_first(hand, &slot1); res != NULL;
364	    res = ohash_next(hand, &slot1)) {
365		slot2 = ohash_lookup_memory(htab,
366		    (char *)res, sizeof(res->page), res->page);
367		if (ohash_find(htab, slot2) == NULL)
368			ohash_insert(htab, slot2, res);
369		else
370			free(res);
371	}
372
373	/* Discard the merged result. */
374
375	ohash_delete(hand);
376	free(hand);
377	return htab;
378}
379
380void
381mansearch_free(struct manpage *res, size_t sz)
382{
383	size_t	 i;
384
385	for (i = 0; i < sz; i++) {
386		free(res[i].file);
387		free(res[i].names);
388		free(res[i].output);
389	}
390	free(res);
391}
392
393static int
394manpage_compare(const void *vp1, const void *vp2)
395{
396	const struct manpage	*mp1, *mp2;
397	const char		*cp1, *cp2;
398	size_t			 sz1, sz2;
399	int			 diff;
400
401	mp1 = vp1;
402	mp2 = vp2;
403	if ((diff = mp2->bits - mp1->bits) ||
404	    (diff = mp1->sec - mp2->sec))
405		return diff;
406
407	/* Fall back to alphabetic ordering of names. */
408	sz1 = strcspn(mp1->names, "(");
409	sz2 = strcspn(mp2->names, "(");
410	if (sz1 < sz2)
411		sz1 = sz2;
412	if ((diff = strncasecmp(mp1->names, mp2->names, sz1)))
413		return diff;
414
415	/* For identical names and sections, prefer arch-dependent. */
416	cp1 = strchr(mp1->names + sz1, '/');
417	cp2 = strchr(mp2->names + sz2, '/');
418	return cp1 != NULL && cp2 != NULL ? strcasecmp(cp1, cp2) :
419	    cp1 != NULL ? -1 : cp2 != NULL ? 1 : 0;
420}
421
422static char *
423buildnames(const struct dbm_page *page)
424{
425	char	*buf;
426	size_t	 i, sz;
427
428	sz = lstlen(page->name, 2) + 1 + lstlen(page->sect, 2) +
429	    (page->arch == NULL ? 0 : 1 + lstlen(page->arch, 2)) + 2;
430	buf = mandoc_malloc(sz);
431	i = 0;
432	lstcat(buf, &i, page->name, ", ");
433	buf[i++] = '(';
434	lstcat(buf, &i, page->sect, ", ");
435	if (page->arch != NULL) {
436		buf[i++] = '/';
437		lstcat(buf, &i, page->arch, ", ");
438	}
439	buf[i++] = ')';
440	buf[i++] = '\0';
441	assert(i == sz);
442	return buf;
443}
444
445/*
446 * Count the buffer space needed to print the NUL-terminated
447 * list of NUL-terminated strings, when printing sep separator
448 * characters between strings.
449 */
450static size_t
451lstlen(const char *cp, size_t sep)
452{
453	size_t	 sz;
454
455	for (sz = 0;; sz++) {
456		if (cp[0] == '\0') {
457			if (cp[1] == '\0')
458				break;
459			sz += sep - 1;
460		} else if (cp[0] < ' ')
461			sz--;
462		cp++;
463	}
464	return sz;
465}
466
467/*
468 * Print the NUL-terminated list of NUL-terminated strings
469 * into the buffer, seperating strings with sep.
470 */
471static void
472lstcat(char *buf, size_t *i, const char *cp, const char *sep)
473{
474	const char *s;
475
476	for (;;) {
477		if (cp[0] == '\0') {
478			if (cp[1] == '\0')
479				break;
480			s = sep;
481			while (*s != '\0')
482				buf[(*i)++] = *s++;
483		} else if (cp[0] >= ' ')
484			buf[(*i)++] = cp[0];
485		cp++;
486	}
487}
488
489/*
490 * Return 1 if the string *want occurs in any of the strings
491 * in the NUL-terminated string list *have, or 0 otherwise.
492 * If either argument is NULL or empty, assume no filtering
493 * is desired and return 1.
494 */
495static int
496lstmatch(const char *want, const char *have)
497{
498        if (want == NULL || have == NULL || *have == '\0')
499                return 1;
500        while (*have != '\0') {
501                if (strcasestr(have, want) != NULL)
502                        return 1;
503                have = strchr(have, '\0') + 1;
504        }
505        return 0;
506}
507
508/*
509 * Build a list of values taken by the macro im in the manual page.
510 */
511static char *
512buildoutput(size_t im, struct dbm_page *page)
513{
514	const char	*oldoutput, *sep, *input;
515	char		*output, *newoutput, *value;
516	size_t		 sz, i;
517
518	switch (im) {
519	case KEY_Nd:
520		return mandoc_strdup(page->desc);
521	case KEY_Nm:
522		input = page->name;
523		break;
524	case KEY_sec:
525		input = page->sect;
526		break;
527	case KEY_arch:
528		input = page->arch;
529		if (input == NULL)
530			input = "all\0";
531		break;
532	default:
533		input = NULL;
534		break;
535	}
536
537	if (input != NULL) {
538		sz = lstlen(input, 3) + 1;
539		output = mandoc_malloc(sz);
540		i = 0;
541		lstcat(output, &i, input, " # ");
542		output[i++] = '\0';
543		assert(i == sz);
544		return output;
545	}
546
547	output = NULL;
548	dbm_macro_bypage(im - 2, page->addr);
549	while ((value = dbm_macro_next()) != NULL) {
550		if (output == NULL) {
551			oldoutput = "";
552			sep = "";
553		} else {
554			oldoutput = output;
555			sep = " # ";
556		}
557		mandoc_asprintf(&newoutput, "%s%s%s", oldoutput, sep, value);
558		free(output);
559		output = newoutput;
560	}
561	return output;
562}
563
564/*
565 * Compile a set of string tokens into an expression.
566 * Tokens in "argv" are assumed to be individual expression atoms (e.g.,
567 * "(", "foo=bar", etc.).
568 */
569static struct expr *
570exprcomp(const struct mansearch *search, int argc, char *argv[], int *argi)
571{
572	struct expr	*parent, *child;
573	int		 needterm, nested;
574
575	if ((nested = *argi) == argc)
576		return NULL;
577	needterm = 1;
578	parent = child = NULL;
579	while (*argi < argc) {
580		if (strcmp(")", argv[*argi]) == 0) {
581			if (needterm)
582				warnx("missing term "
583				    "before closing parenthesis");
584			needterm = 0;
585			if (nested)
586				break;
587			warnx("ignoring unmatched right parenthesis");
588			++*argi;
589			continue;
590		}
591		if (strcmp("-o", argv[*argi]) == 0) {
592			if (needterm) {
593				if (*argi > 0)
594					warnx("ignoring -o after %s",
595					    argv[*argi - 1]);
596				else
597					warnx("ignoring initial -o");
598			}
599			needterm = 1;
600			++*argi;
601			continue;
602		}
603		needterm = 0;
604		if (child == NULL) {
605			child = expr_and(search, argc, argv, argi);
606			continue;
607		}
608		if (parent == NULL) {
609			parent = mandoc_calloc(1, sizeof(*parent));
610			parent->type = EXPR_OR;
611			parent->next = NULL;
612			parent->child = child;
613		}
614		child->next = expr_and(search, argc, argv, argi);
615		child = child->next;
616	}
617	if (needterm && *argi)
618		warnx("ignoring trailing %s", argv[*argi - 1]);
619	return parent == NULL ? child : parent;
620}
621
622static struct expr *
623expr_and(const struct mansearch *search, int argc, char *argv[], int *argi)
624{
625	struct expr	*parent, *child;
626	int		 needterm;
627
628	needterm = 1;
629	parent = child = NULL;
630	while (*argi < argc) {
631		if (strcmp(")", argv[*argi]) == 0) {
632			if (needterm)
633				warnx("missing term "
634				    "before closing parenthesis");
635			needterm = 0;
636			break;
637		}
638		if (strcmp("-o", argv[*argi]) == 0)
639			break;
640		if (strcmp("-a", argv[*argi]) == 0) {
641			if (needterm) {
642				if (*argi > 0)
643					warnx("ignoring -a after %s",
644					    argv[*argi - 1]);
645				else
646					warnx("ignoring initial -a");
647			}
648			needterm = 1;
649			++*argi;
650			continue;
651		}
652		if (needterm == 0)
653			break;
654		if (child == NULL) {
655			child = exprterm(search, argc, argv, argi);
656			if (child != NULL)
657				needterm = 0;
658			continue;
659		}
660		needterm = 0;
661		if (parent == NULL) {
662			parent = mandoc_calloc(1, sizeof(*parent));
663			parent->type = EXPR_AND;
664			parent->next = NULL;
665			parent->child = child;
666		}
667		child->next = exprterm(search, argc, argv, argi);
668		if (child->next != NULL) {
669			child = child->next;
670			needterm = 0;
671		}
672	}
673	if (needterm && *argi)
674		warnx("ignoring trailing %s", argv[*argi - 1]);
675	return parent == NULL ? child : parent;
676}
677
678static struct expr *
679exprterm(const struct mansearch *search, int argc, char *argv[], int *argi)
680{
681	char		 errbuf[BUFSIZ];
682	struct expr	*e;
683	char		*key, *val;
684	uint64_t	 iterbit;
685	int		 cs, i, irc;
686
687	if (strcmp("(", argv[*argi]) == 0) {
688		++*argi;
689		e = exprcomp(search, argc, argv, argi);
690		if (*argi < argc) {
691			assert(strcmp(")", argv[*argi]) == 0);
692			++*argi;
693		} else
694			warnx("unclosed parenthesis");
695		return e;
696	}
697
698	if (strcmp("-i", argv[*argi]) == 0 && *argi + 1 < argc) {
699		cs = 0;
700		++*argi;
701	} else
702		cs = 1;
703
704	e = mandoc_calloc(1, sizeof(*e));
705	e->type = EXPR_TERM;
706	e->bits = 0;
707	e->next = NULL;
708	e->child = NULL;
709
710	if (search->argmode == ARG_NAME) {
711		e->bits = TYPE_Nm;
712		e->match.type = DBM_EXACT;
713		e->match.str = argv[(*argi)++];
714		return e;
715	}
716
717	/*
718	 * Separate macro keys from search string.
719	 * If needed, request regular expression handling.
720	 */
721
722	if (search->argmode == ARG_WORD) {
723		e->bits = TYPE_Nm;
724		e->match.type = DBM_REGEX;
725#if HAVE_REWB_BSD
726		mandoc_asprintf(&val, "[[:<:]]%s[[:>:]]", argv[*argi]);
727#elif HAVE_REWB_SYSV
728		mandoc_asprintf(&val, "\\<%s\\>", argv[*argi]);
729#else
730		mandoc_asprintf(&val,
731		    "(^|[^a-zA-Z01-9_])%s([^a-zA-Z01-9_]|$)", argv[*argi]);
732#endif
733		cs = 0;
734	} else if ((val = strpbrk(argv[*argi], "=~")) == NULL) {
735		e->bits = TYPE_Nm | TYPE_Nd;
736		e->match.type = DBM_SUB;
737		e->match.str = argv[*argi];
738	} else {
739		if (val == argv[*argi])
740			e->bits = TYPE_Nm | TYPE_Nd;
741		if (*val == '=') {
742			e->match.type = DBM_SUB;
743			e->match.str = val + 1;
744		} else
745			e->match.type = DBM_REGEX;
746		*val++ = '\0';
747		if (strstr(argv[*argi], "arch") != NULL)
748			cs = 0;
749	}
750
751	/* Compile regular expressions. */
752
753	if (e->match.type == DBM_REGEX) {
754		e->match.re = mandoc_malloc(sizeof(*e->match.re));
755		irc = regcomp(e->match.re, val,
756		    REG_EXTENDED | REG_NOSUB | (cs ? 0 : REG_ICASE));
757		if (irc) {
758			regerror(irc, e->match.re, errbuf, sizeof(errbuf));
759			warnx("regcomp /%s/: %s", val, errbuf);
760		}
761		if (search->argmode == ARG_WORD)
762			free(val);
763		if (irc) {
764			free(e->match.re);
765			free(e);
766			++*argi;
767			return NULL;
768		}
769	}
770
771	if (e->bits) {
772		++*argi;
773		return e;
774	}
775
776	/*
777	 * Parse out all possible fields.
778	 * If the field doesn't resolve, bail.
779	 */
780
781	while (NULL != (key = strsep(&argv[*argi], ","))) {
782		if ('\0' == *key)
783			continue;
784		for (i = 0, iterbit = 1; i < KEY_MAX; i++, iterbit <<= 1) {
785			if (0 == strcasecmp(key, mansearch_keynames[i])) {
786				e->bits |= iterbit;
787				break;
788			}
789		}
790		if (i == KEY_MAX) {
791			if (strcasecmp(key, "any"))
792				warnx("treating unknown key "
793				    "\"%s\" as \"any\"", key);
794			e->bits |= ~0ULL;
795		}
796	}
797
798	++*argi;
799	return e;
800}
801
802static void
803exprfree(struct expr *e)
804{
805	if (e->next != NULL)
806		exprfree(e->next);
807	if (e->child != NULL)
808		exprfree(e->child);
809	free(e);
810}
811