xref: /illumos-gate/usr/src/cmd/mandoc/mandocdb.c (revision c66b8046)
1 /*	$Id: mandocdb.c,v 1.253 2017/07/28 14:48:25 schwarze Exp $ */
2 /*
3  * Copyright (c) 2011, 2012 Kristaps Dzonsons <kristaps@bsd.lv>
4  * Copyright (c) 2011-2017 Ingo Schwarze <schwarze@openbsd.org>
5  * Copyright (c) 2016 Ed Maste <emaste@freebsd.org>
6  *
7  * Permission to use, copy, modify, and distribute this software for any
8  * purpose with or without fee is hereby granted, provided that the above
9  * copyright notice and this permission notice appear in all copies.
10  *
11  * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHORS DISCLAIM ALL WARRANTIES
12  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13  * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHORS BE LIABLE FOR
14  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
16  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
17  * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
18  */
19 #include "config.h"
20 
21 #include <sys/types.h>
22 #include <sys/stat.h>
23 #include <sys/wait.h>
24 
25 #include <assert.h>
26 #include <ctype.h>
27 #if HAVE_ERR
28 #include <err.h>
29 #endif
30 #include <errno.h>
31 #include <fcntl.h>
32 #if HAVE_FTS
33 #include <fts.h>
34 #else
35 #include "compat_fts.h"
36 #endif
37 #include <limits.h>
38 #if HAVE_SANDBOX_INIT
39 #include <sandbox.h>
40 #endif
41 #include <stdarg.h>
42 #include <stddef.h>
43 #include <stdio.h>
44 #include <stdint.h>
45 #include <stdlib.h>
46 #include <string.h>
47 #include <unistd.h>
48 
49 #include "mandoc_aux.h"
50 #include "mandoc_ohash.h"
51 #include "mandoc.h"
52 #include "roff.h"
53 #include "mdoc.h"
54 #include "man.h"
55 #include "manconf.h"
56 #include "mansearch.h"
57 #include "dba_array.h"
58 #include "dba.h"
59 
60 extern const char *const mansearch_keynames[];
61 
62 enum	op {
63 	OP_DEFAULT = 0, /* new dbs from dir list or default config */
64 	OP_CONFFILE, /* new databases from custom config file */
65 	OP_UPDATE, /* delete/add entries in existing database */
66 	OP_DELETE, /* delete entries from existing database */
67 	OP_TEST /* change no databases, report potential problems */
68 };
69 
70 struct	str {
71 	const struct mpage *mpage; /* if set, the owning parse */
72 	uint64_t	 mask; /* bitmask in sequence */
73 	char		 key[]; /* rendered text */
74 };
75 
76 struct	inodev {
77 	ino_t		 st_ino;
78 	dev_t		 st_dev;
79 };
80 
81 struct	mpage {
82 	struct inodev	 inodev;  /* used for hashing routine */
83 	struct dba_array *dba;
84 	char		*sec;     /* section from file content */
85 	char		*arch;    /* architecture from file content */
86 	char		*title;   /* title from file content */
87 	char		*desc;    /* description from file content */
88 	struct mpage	*next;    /* singly linked list */
89 	struct mlink	*mlinks;  /* singly linked list */
90 	int		 name_head_done;
91 	enum form	 form;    /* format from file content */
92 };
93 
94 struct	mlink {
95 	char		 file[PATH_MAX]; /* filename rel. to manpath */
96 	char		*dsec;    /* section from directory */
97 	char		*arch;    /* architecture from directory */
98 	char		*name;    /* name from file name (not empty) */
99 	char		*fsec;    /* section from file name suffix */
100 	struct mlink	*next;    /* singly linked list */
101 	struct mpage	*mpage;   /* parent */
102 	int		 gzip;	  /* filename has a .gz suffix */
103 	enum form	 dform;   /* format from directory */
104 	enum form	 fform;   /* format from file name suffix */
105 };
106 
107 typedef	int (*mdoc_fp)(struct mpage *, const struct roff_meta *,
108 			const struct roff_node *);
109 
110 struct	mdoc_handler {
111 	mdoc_fp		 fp; /* optional handler */
112 	uint64_t	 mask;  /* set unless handler returns 0 */
113 	int		 taboo;  /* node flags that must not be set */
114 };
115 
116 
117 int		 mandocdb(int, char *[]);
118 
119 static	void	 dbadd(struct dba *, struct mpage *);
120 static	void	 dbadd_mlink(const struct mlink *mlink);
121 static	void	 dbprune(struct dba *);
122 static	void	 dbwrite(struct dba *);
123 static	void	 filescan(const char *);
124 #if HAVE_FTS_COMPARE_CONST
125 static	int	 fts_compare(const FTSENT *const *, const FTSENT *const *);
126 #else
127 static	int	 fts_compare(const FTSENT **, const FTSENT **);
128 #endif
129 static	void	 mlink_add(struct mlink *, const struct stat *);
130 static	void	 mlink_check(struct mpage *, struct mlink *);
131 static	void	 mlink_free(struct mlink *);
132 static	void	 mlinks_undupe(struct mpage *);
133 static	void	 mpages_free(void);
134 static	void	 mpages_merge(struct dba *, struct mparse *);
135 static	void	 parse_cat(struct mpage *, int);
136 static	void	 parse_man(struct mpage *, const struct roff_meta *,
137 			const struct roff_node *);
138 static	void	 parse_mdoc(struct mpage *, const struct roff_meta *,
139 			const struct roff_node *);
140 static	int	 parse_mdoc_head(struct mpage *, const struct roff_meta *,
141 			const struct roff_node *);
142 static	int	 parse_mdoc_Fd(struct mpage *, const struct roff_meta *,
143 			const struct roff_node *);
144 static	void	 parse_mdoc_fname(struct mpage *, const struct roff_node *);
145 static	int	 parse_mdoc_Fn(struct mpage *, const struct roff_meta *,
146 			const struct roff_node *);
147 static	int	 parse_mdoc_Fo(struct mpage *, const struct roff_meta *,
148 			const struct roff_node *);
149 static	int	 parse_mdoc_Nd(struct mpage *, const struct roff_meta *,
150 			const struct roff_node *);
151 static	int	 parse_mdoc_Nm(struct mpage *, const struct roff_meta *,
152 			const struct roff_node *);
153 static	int	 parse_mdoc_Sh(struct mpage *, const struct roff_meta *,
154 			const struct roff_node *);
155 static	int	 parse_mdoc_Va(struct mpage *, const struct roff_meta *,
156 			const struct roff_node *);
157 static	int	 parse_mdoc_Xr(struct mpage *, const struct roff_meta *,
158 			const struct roff_node *);
159 static	void	 putkey(const struct mpage *, char *, uint64_t);
160 static	void	 putkeys(const struct mpage *, char *, size_t, uint64_t);
161 static	void	 putmdockey(const struct mpage *,
162 			const struct roff_node *, uint64_t, int);
163 static	int	 render_string(char **, size_t *);
164 static	void	 say(const char *, const char *, ...)
165 			__attribute__((__format__ (__printf__, 2, 3)));
166 static	int	 set_basedir(const char *, int);
167 static	int	 treescan(void);
168 static	size_t	 utf8(unsigned int, char [7]);
169 
170 static	int		 nodb; /* no database changes */
171 static	int		 mparse_options; /* abort the parse early */
172 static	int		 use_all; /* use all found files */
173 static	int		 debug; /* print what we're doing */
174 static	int		 warnings; /* warn about crap */
175 static	int		 write_utf8; /* write UTF-8 output; else ASCII */
176 static	int		 exitcode; /* to be returned by main */
177 static	enum op		 op; /* operational mode */
178 static	char		 basedir[PATH_MAX]; /* current base directory */
179 static	struct mpage	*mpage_head; /* list of distinct manual pages */
180 static	struct ohash	 mpages; /* table of distinct manual pages */
181 static	struct ohash	 mlinks; /* table of directory entries */
182 static	struct ohash	 names; /* table of all names */
183 static	struct ohash	 strings; /* table of all strings */
184 static	uint64_t	 name_mask;
185 
186 static	const struct mdoc_handler __mdocs[MDOC_MAX - MDOC_Dd] = {
187 	{ NULL, 0, NODE_NOPRT },  /* Dd */
188 	{ NULL, 0, NODE_NOPRT },  /* Dt */
189 	{ NULL, 0, NODE_NOPRT },  /* Os */
190 	{ parse_mdoc_Sh, TYPE_Sh, 0 }, /* Sh */
191 	{ parse_mdoc_head, TYPE_Ss, 0 }, /* Ss */
192 	{ NULL, 0, 0 },  /* Pp */
193 	{ NULL, 0, 0 },  /* D1 */
194 	{ NULL, 0, 0 },  /* Dl */
195 	{ NULL, 0, 0 },  /* Bd */
196 	{ NULL, 0, 0 },  /* Ed */
197 	{ NULL, 0, 0 },  /* Bl */
198 	{ NULL, 0, 0 },  /* El */
199 	{ NULL, 0, 0 },  /* It */
200 	{ NULL, 0, 0 },  /* Ad */
201 	{ NULL, TYPE_An, 0 },  /* An */
202 	{ NULL, 0, 0 },  /* Ap */
203 	{ NULL, TYPE_Ar, 0 },  /* Ar */
204 	{ NULL, TYPE_Cd, 0 },  /* Cd */
205 	{ NULL, TYPE_Cm, 0 },  /* Cm */
206 	{ NULL, TYPE_Dv, 0 },  /* Dv */
207 	{ NULL, TYPE_Er, 0 },  /* Er */
208 	{ NULL, TYPE_Ev, 0 },  /* Ev */
209 	{ NULL, 0, 0 },  /* Ex */
210 	{ NULL, TYPE_Fa, 0 },  /* Fa */
211 	{ parse_mdoc_Fd, 0, 0 },  /* Fd */
212 	{ NULL, TYPE_Fl, 0 },  /* Fl */
213 	{ parse_mdoc_Fn, 0, 0 },  /* Fn */
214 	{ NULL, TYPE_Ft, 0 },  /* Ft */
215 	{ NULL, TYPE_Ic, 0 },  /* Ic */
216 	{ NULL, TYPE_In, 0 },  /* In */
217 	{ NULL, TYPE_Li, 0 },  /* Li */
218 	{ parse_mdoc_Nd, 0, 0 },  /* Nd */
219 	{ parse_mdoc_Nm, 0, 0 },  /* Nm */
220 	{ NULL, 0, 0 },  /* Op */
221 	{ NULL, 0, 0 },  /* Ot */
222 	{ NULL, TYPE_Pa, NODE_NOSRC },  /* Pa */
223 	{ NULL, 0, 0 },  /* Rv */
224 	{ NULL, TYPE_St, 0 },  /* St */
225 	{ parse_mdoc_Va, TYPE_Va, 0 },  /* Va */
226 	{ parse_mdoc_Va, TYPE_Vt, 0 },  /* Vt */
227 	{ parse_mdoc_Xr, 0, 0 },  /* Xr */
228 	{ NULL, 0, 0 },  /* %A */
229 	{ NULL, 0, 0 },  /* %B */
230 	{ NULL, 0, 0 },  /* %D */
231 	{ NULL, 0, 0 },  /* %I */
232 	{ NULL, 0, 0 },  /* %J */
233 	{ NULL, 0, 0 },  /* %N */
234 	{ NULL, 0, 0 },  /* %O */
235 	{ NULL, 0, 0 },  /* %P */
236 	{ NULL, 0, 0 },  /* %R */
237 	{ NULL, 0, 0 },  /* %T */
238 	{ NULL, 0, 0 },  /* %V */
239 	{ NULL, 0, 0 },  /* Ac */
240 	{ NULL, 0, 0 },  /* Ao */
241 	{ NULL, 0, 0 },  /* Aq */
242 	{ NULL, TYPE_At, 0 },  /* At */
243 	{ NULL, 0, 0 },  /* Bc */
244 	{ NULL, 0, 0 },  /* Bf */
245 	{ NULL, 0, 0 },  /* Bo */
246 	{ NULL, 0, 0 },  /* Bq */
247 	{ NULL, TYPE_Bsx, NODE_NOSRC },  /* Bsx */
248 	{ NULL, TYPE_Bx, NODE_NOSRC },  /* Bx */
249 	{ NULL, 0, 0 },  /* Db */
250 	{ NULL, 0, 0 },  /* Dc */
251 	{ NULL, 0, 0 },  /* Do */
252 	{ NULL, 0, 0 },  /* Dq */
253 	{ NULL, 0, 0 },  /* Ec */
254 	{ NULL, 0, 0 },  /* Ef */
255 	{ NULL, TYPE_Em, 0 },  /* Em */
256 	{ NULL, 0, 0 },  /* Eo */
257 	{ NULL, TYPE_Fx, NODE_NOSRC },  /* Fx */
258 	{ NULL, TYPE_Ms, 0 },  /* Ms */
259 	{ NULL, 0, 0 },  /* No */
260 	{ NULL, 0, 0 },  /* Ns */
261 	{ NULL, TYPE_Nx, NODE_NOSRC },  /* Nx */
262 	{ NULL, TYPE_Ox, NODE_NOSRC },  /* Ox */
263 	{ NULL, 0, 0 },  /* Pc */
264 	{ NULL, 0, 0 },  /* Pf */
265 	{ NULL, 0, 0 },  /* Po */
266 	{ NULL, 0, 0 },  /* Pq */
267 	{ NULL, 0, 0 },  /* Qc */
268 	{ NULL, 0, 0 },  /* Ql */
269 	{ NULL, 0, 0 },  /* Qo */
270 	{ NULL, 0, 0 },  /* Qq */
271 	{ NULL, 0, 0 },  /* Re */
272 	{ NULL, 0, 0 },  /* Rs */
273 	{ NULL, 0, 0 },  /* Sc */
274 	{ NULL, 0, 0 },  /* So */
275 	{ NULL, 0, 0 },  /* Sq */
276 	{ NULL, 0, 0 },  /* Sm */
277 	{ NULL, 0, 0 },  /* Sx */
278 	{ NULL, TYPE_Sy, 0 },  /* Sy */
279 	{ NULL, TYPE_Tn, 0 },  /* Tn */
280 	{ NULL, 0, NODE_NOSRC },  /* Ux */
281 	{ NULL, 0, 0 },  /* Xc */
282 	{ NULL, 0, 0 },  /* Xo */
283 	{ parse_mdoc_Fo, 0, 0 },  /* Fo */
284 	{ NULL, 0, 0 },  /* Fc */
285 	{ NULL, 0, 0 },  /* Oo */
286 	{ NULL, 0, 0 },  /* Oc */
287 	{ NULL, 0, 0 },  /* Bk */
288 	{ NULL, 0, 0 },  /* Ek */
289 	{ NULL, 0, 0 },  /* Bt */
290 	{ NULL, 0, 0 },  /* Hf */
291 	{ NULL, 0, 0 },  /* Fr */
292 	{ NULL, 0, 0 },  /* Ud */
293 	{ NULL, TYPE_Lb, NODE_NOSRC },  /* Lb */
294 	{ NULL, 0, 0 },  /* Lp */
295 	{ NULL, TYPE_Lk, 0 },  /* Lk */
296 	{ NULL, TYPE_Mt, NODE_NOSRC },  /* Mt */
297 	{ NULL, 0, 0 },  /* Brq */
298 	{ NULL, 0, 0 },  /* Bro */
299 	{ NULL, 0, 0 },  /* Brc */
300 	{ NULL, 0, 0 },  /* %C */
301 	{ NULL, 0, 0 },  /* Es */
302 	{ NULL, 0, 0 },  /* En */
303 	{ NULL, TYPE_Dx, NODE_NOSRC },  /* Dx */
304 	{ NULL, 0, 0 },  /* %Q */
305 	{ NULL, 0, 0 },  /* %U */
306 	{ NULL, 0, 0 },  /* Ta */
307 };
308 static	const struct mdoc_handler *const mdocs = __mdocs - MDOC_Dd;
309 
310 
311 int
312 mandocdb(int argc, char *argv[])
313 {
314 	struct manconf	  conf;
315 	struct mparse	 *mp;
316 	struct dba	 *dba;
317 	const char	 *path_arg, *progname;
318 	size_t		  j, sz;
319 	int		  ch, i;
320 
321 #if HAVE_PLEDGE
322 	if (pledge("stdio rpath wpath cpath fattr flock proc exec", NULL) == -1) {
323 		warn("pledge");
324 		return (int)MANDOCLEVEL_SYSERR;
325 	}
326 #endif
327 
328 #if HAVE_SANDBOX_INIT
329 	if (sandbox_init(kSBXProfileNoInternet, SANDBOX_NAMED, NULL) == -1) {
330 		warnx("sandbox_init");
331 		return (int)MANDOCLEVEL_SYSERR;
332 	}
333 #endif
334 
335 	memset(&conf, 0, sizeof(conf));
336 
337 	/*
338 	 * We accept a few different invocations.
339 	 * The CHECKOP macro makes sure that invocation styles don't
340 	 * clobber each other.
341 	 */
342 #define	CHECKOP(_op, _ch) do \
343 	if (OP_DEFAULT != (_op)) { \
344 		warnx("-%c: Conflicting option", (_ch)); \
345 		goto usage; \
346 	} while (/*CONSTCOND*/0)
347 
348 	path_arg = NULL;
349 	op = OP_DEFAULT;
350 
351 	while (-1 != (ch = getopt(argc, argv, "aC:Dd:npQT:tu:v")))
352 		switch (ch) {
353 		case 'a':
354 			use_all = 1;
355 			break;
356 		case 'C':
357 			CHECKOP(op, ch);
358 			path_arg = optarg;
359 			op = OP_CONFFILE;
360 			break;
361 		case 'D':
362 			debug++;
363 			break;
364 		case 'd':
365 			CHECKOP(op, ch);
366 			path_arg = optarg;
367 			op = OP_UPDATE;
368 			break;
369 		case 'n':
370 			nodb = 1;
371 			break;
372 		case 'p':
373 			warnings = 1;
374 			break;
375 		case 'Q':
376 			mparse_options |= MPARSE_QUICK;
377 			break;
378 		case 'T':
379 			if (strcmp(optarg, "utf8")) {
380 				warnx("-T%s: Unsupported output format",
381 				    optarg);
382 				goto usage;
383 			}
384 			write_utf8 = 1;
385 			break;
386 		case 't':
387 			CHECKOP(op, ch);
388 			dup2(STDOUT_FILENO, STDERR_FILENO);
389 			op = OP_TEST;
390 			nodb = warnings = 1;
391 			break;
392 		case 'u':
393 			CHECKOP(op, ch);
394 			path_arg = optarg;
395 			op = OP_DELETE;
396 			break;
397 		case 'v':
398 			/* Compatibility with espie@'s makewhatis. */
399 			break;
400 		default:
401 			goto usage;
402 		}
403 
404 	argc -= optind;
405 	argv += optind;
406 
407 #if HAVE_PLEDGE
408 	if (nodb) {
409 		if (pledge("stdio rpath", NULL) == -1) {
410 			warn("pledge");
411 			return (int)MANDOCLEVEL_SYSERR;
412 		}
413 	}
414 #endif
415 
416 	if (OP_CONFFILE == op && argc > 0) {
417 		warnx("-C: Too many arguments");
418 		goto usage;
419 	}
420 
421 	exitcode = (int)MANDOCLEVEL_OK;
422 	mchars_alloc();
423 	mp = mparse_alloc(mparse_options, MANDOCERR_MAX, NULL,
424 	    MANDOC_OS_OTHER, NULL);
425 	mandoc_ohash_init(&mpages, 6, offsetof(struct mpage, inodev));
426 	mandoc_ohash_init(&mlinks, 6, offsetof(struct mlink, file));
427 
428 	if (OP_UPDATE == op || OP_DELETE == op || OP_TEST == op) {
429 
430 		/*
431 		 * Most of these deal with a specific directory.
432 		 * Jump into that directory first.
433 		 */
434 		if (OP_TEST != op && 0 == set_basedir(path_arg, 1))
435 			goto out;
436 
437 		dba = nodb ? dba_new(128) : dba_read(MANDOC_DB);
438 		if (dba != NULL) {
439 			/*
440 			 * The existing database is usable.  Process
441 			 * all files specified on the command-line.
442 			 */
443 #if HAVE_PLEDGE
444 			if (!nodb) {
445 				if (pledge("stdio rpath wpath cpath fattr flock", NULL) == -1) {
446 					warn("pledge");
447 					exitcode = (int)MANDOCLEVEL_SYSERR;
448 					goto out;
449 				}
450 			}
451 #endif
452 			use_all = 1;
453 			for (i = 0; i < argc; i++)
454 				filescan(argv[i]);
455 			if (nodb == 0)
456 				dbprune(dba);
457 		} else {
458 			/* Database missing or corrupt. */
459 			if (op != OP_UPDATE || errno != ENOENT)
460 				say(MANDOC_DB, "%s: Automatically recreating"
461 				    " from scratch", strerror(errno));
462 			exitcode = (int)MANDOCLEVEL_OK;
463 			op = OP_DEFAULT;
464 			if (0 == treescan())
465 				goto out;
466 			dba = dba_new(128);
467 		}
468 		if (OP_DELETE != op)
469 			mpages_merge(dba, mp);
470 		if (nodb == 0)
471 			dbwrite(dba);
472 		dba_free(dba);
473 	} else {
474 		/*
475 		 * If we have arguments, use them as our manpaths.
476 		 * If we don't, use man.conf(5).
477 		 */
478 		if (argc > 0) {
479 			conf.manpath.paths = mandoc_reallocarray(NULL,
480 			    argc, sizeof(char *));
481 			conf.manpath.sz = (size_t)argc;
482 			for (i = 0; i < argc; i++)
483 				conf.manpath.paths[i] = mandoc_strdup(argv[i]);
484 		} else
485 			manconf_parse(&conf, path_arg, NULL, NULL);
486 
487 		if (conf.manpath.sz == 0) {
488 			exitcode = (int)MANDOCLEVEL_BADARG;
489 			say("", "Empty manpath");
490 		}
491 
492 		/*
493 		 * First scan the tree rooted at a base directory, then
494 		 * build a new database and finally move it into place.
495 		 * Ignore zero-length directories and strip trailing
496 		 * slashes.
497 		 */
498 		for (j = 0; j < conf.manpath.sz; j++) {
499 			sz = strlen(conf.manpath.paths[j]);
500 			if (sz && conf.manpath.paths[j][sz - 1] == '/')
501 				conf.manpath.paths[j][--sz] = '\0';
502 			if (0 == sz)
503 				continue;
504 
505 			if (j) {
506 				mandoc_ohash_init(&mpages, 6,
507 				    offsetof(struct mpage, inodev));
508 				mandoc_ohash_init(&mlinks, 6,
509 				    offsetof(struct mlink, file));
510 			}
511 
512 			if ( ! set_basedir(conf.manpath.paths[j], argc > 0))
513 				continue;
514 			if (0 == treescan())
515 				continue;
516 			dba = dba_new(128);
517 			mpages_merge(dba, mp);
518 			if (nodb == 0)
519 				dbwrite(dba);
520 			dba_free(dba);
521 
522 			if (j + 1 < conf.manpath.sz) {
523 				mpages_free();
524 				ohash_delete(&mpages);
525 				ohash_delete(&mlinks);
526 			}
527 		}
528 	}
529 out:
530 	manconf_free(&conf);
531 	mparse_free(mp);
532 	mchars_free();
533 	mpages_free();
534 	ohash_delete(&mpages);
535 	ohash_delete(&mlinks);
536 	return exitcode;
537 usage:
538 	progname = getprogname();
539 	fprintf(stderr, "usage: %s [-aDnpQ] [-C file] [-Tutf8]\n"
540 			"       %s [-aDnpQ] [-Tutf8] dir ...\n"
541 			"       %s [-DnpQ] [-Tutf8] -d dir [file ...]\n"
542 			"       %s [-Dnp] -u dir [file ...]\n"
543 			"       %s [-Q] -t file ...\n",
544 		        progname, progname, progname, progname, progname);
545 
546 	return (int)MANDOCLEVEL_BADARG;
547 }
548 
549 /*
550  * To get a singly linked list in alpha order while inserting entries
551  * at the beginning, process directory entries in reverse alpha order.
552  */
553 static int
554 #if HAVE_FTS_COMPARE_CONST
555 fts_compare(const FTSENT *const *a, const FTSENT *const *b)
556 #else
557 fts_compare(const FTSENT **a, const FTSENT **b)
558 #endif
559 {
560 	return -strcmp((*a)->fts_name, (*b)->fts_name);
561 }
562 
563 /*
564  * Scan a directory tree rooted at "basedir" for manpages.
565  * We use fts(), scanning directory parts along the way for clues to our
566  * section and architecture.
567  *
568  * If use_all has been specified, grok all files.
569  * If not, sanitise paths to the following:
570  *
571  *   [./]man*[/<arch>]/<name>.<section>
572  *   or
573  *   [./]cat<section>[/<arch>]/<name>.0
574  *
575  * TODO: accommodate for multi-language directories.
576  */
577 static int
578 treescan(void)
579 {
580 	char		 buf[PATH_MAX];
581 	FTS		*f;
582 	FTSENT		*ff;
583 	struct mlink	*mlink;
584 	int		 gzip;
585 	enum form	 dform;
586 	char		*dsec, *arch, *fsec, *cp;
587 	const char	*path;
588 	const char	*argv[2];
589 
590 	argv[0] = ".";
591 	argv[1] = NULL;
592 
593 	f = fts_open((char * const *)argv, FTS_PHYSICAL | FTS_NOCHDIR,
594 	    fts_compare);
595 	if (f == NULL) {
596 		exitcode = (int)MANDOCLEVEL_SYSERR;
597 		say("", "&fts_open");
598 		return 0;
599 	}
600 
601 	dsec = arch = NULL;
602 	dform = FORM_NONE;
603 
604 	while ((ff = fts_read(f)) != NULL) {
605 		path = ff->fts_path + 2;
606 		switch (ff->fts_info) {
607 
608 		/*
609 		 * Symbolic links require various sanity checks,
610 		 * then get handled just like regular files.
611 		 */
612 		case FTS_SL:
613 			if (realpath(path, buf) == NULL) {
614 				if (warnings)
615 					say(path, "&realpath");
616 				continue;
617 			}
618 			if (strstr(buf, basedir) != buf
619 #ifdef HOMEBREWDIR
620 			    && strstr(buf, HOMEBREWDIR) != buf
621 #endif
622 			) {
623 				if (warnings) say("",
624 				    "%s: outside base directory", buf);
625 				continue;
626 			}
627 			/* Use logical inode to avoid mpages dupe. */
628 			if (stat(path, ff->fts_statp) == -1) {
629 				if (warnings)
630 					say(path, "&stat");
631 				continue;
632 			}
633 			/* FALLTHROUGH */
634 
635 		/*
636 		 * If we're a regular file, add an mlink by using the
637 		 * stored directory data and handling the filename.
638 		 */
639 		case FTS_F:
640 			if ( ! strcmp(path, MANDOC_DB))
641 				continue;
642 			if ( ! use_all && ff->fts_level < 2) {
643 				if (warnings)
644 					say(path, "Extraneous file");
645 				continue;
646 			}
647 			gzip = 0;
648 			fsec = NULL;
649 			while (fsec == NULL) {
650 				fsec = strrchr(ff->fts_name, '.');
651 				if (fsec == NULL || strcmp(fsec+1, "gz"))
652 					break;
653 				gzip = 1;
654 				*fsec = '\0';
655 				fsec = NULL;
656 			}
657 			if (fsec == NULL) {
658 				if ( ! use_all) {
659 					if (warnings)
660 						say(path,
661 						    "No filename suffix");
662 					continue;
663 				}
664 			} else if ( ! strcmp(++fsec, "html")) {
665 				if (warnings)
666 					say(path, "Skip html");
667 				continue;
668 			} else if ( ! strcmp(fsec, "ps")) {
669 				if (warnings)
670 					say(path, "Skip ps");
671 				continue;
672 			} else if ( ! strcmp(fsec, "pdf")) {
673 				if (warnings)
674 					say(path, "Skip pdf");
675 				continue;
676 			} else if ( ! use_all &&
677 			    ((dform == FORM_SRC &&
678 			      strncmp(fsec, dsec, strlen(dsec))) ||
679 			     (dform == FORM_CAT && strcmp(fsec, "0")))) {
680 				if (warnings)
681 					say(path, "Wrong filename suffix");
682 				continue;
683 			} else
684 				fsec[-1] = '\0';
685 
686 			mlink = mandoc_calloc(1, sizeof(struct mlink));
687 			if (strlcpy(mlink->file, path,
688 			    sizeof(mlink->file)) >=
689 			    sizeof(mlink->file)) {
690 				say(path, "Filename too long");
691 				free(mlink);
692 				continue;
693 			}
694 			mlink->dform = dform;
695 			mlink->dsec = dsec;
696 			mlink->arch = arch;
697 			mlink->name = ff->fts_name;
698 			mlink->fsec = fsec;
699 			mlink->gzip = gzip;
700 			mlink_add(mlink, ff->fts_statp);
701 			continue;
702 
703 		case FTS_D:
704 		case FTS_DP:
705 			break;
706 
707 		default:
708 			if (warnings)
709 				say(path, "Not a regular file");
710 			continue;
711 		}
712 
713 		switch (ff->fts_level) {
714 		case 0:
715 			/* Ignore the root directory. */
716 			break;
717 		case 1:
718 			/*
719 			 * This might contain manX/ or catX/.
720 			 * Try to infer this from the name.
721 			 * If we're not in use_all, enforce it.
722 			 */
723 			cp = ff->fts_name;
724 			if (ff->fts_info == FTS_DP) {
725 				dform = FORM_NONE;
726 				dsec = NULL;
727 				break;
728 			}
729 
730 			if ( ! strncmp(cp, "man", 3)) {
731 				dform = FORM_SRC;
732 				dsec = cp + 3;
733 			} else if ( ! strncmp(cp, "cat", 3)) {
734 				dform = FORM_CAT;
735 				dsec = cp + 3;
736 			} else {
737 				dform = FORM_NONE;
738 				dsec = NULL;
739 			}
740 
741 			if (dsec != NULL || use_all)
742 				break;
743 
744 			if (warnings)
745 				say(path, "Unknown directory part");
746 			fts_set(f, ff, FTS_SKIP);
747 			break;
748 		case 2:
749 			/*
750 			 * Possibly our architecture.
751 			 * If we're descending, keep tabs on it.
752 			 */
753 			if (ff->fts_info != FTS_DP && dsec != NULL)
754 				arch = ff->fts_name;
755 			else
756 				arch = NULL;
757 			break;
758 		default:
759 			if (ff->fts_info == FTS_DP || use_all)
760 				break;
761 			if (warnings)
762 				say(path, "Extraneous directory part");
763 			fts_set(f, ff, FTS_SKIP);
764 			break;
765 		}
766 	}
767 
768 	fts_close(f);
769 	return 1;
770 }
771 
772 /*
773  * Add a file to the mlinks table.
774  * Do not verify that it's a "valid" looking manpage (we'll do that
775  * later).
776  *
777  * Try to infer the manual section, architecture, and page name from the
778  * path, assuming it looks like
779  *
780  *   [./]man*[/<arch>]/<name>.<section>
781  *   or
782  *   [./]cat<section>[/<arch>]/<name>.0
783  *
784  * See treescan() for the fts(3) version of this.
785  */
786 static void
787 filescan(const char *file)
788 {
789 	char		 buf[PATH_MAX];
790 	struct stat	 st;
791 	struct mlink	*mlink;
792 	char		*p, *start;
793 
794 	assert(use_all);
795 
796 	if (0 == strncmp(file, "./", 2))
797 		file += 2;
798 
799 	/*
800 	 * We have to do lstat(2) before realpath(3) loses
801 	 * the information whether this is a symbolic link.
802 	 * We need to know that because for symbolic links,
803 	 * we want to use the orginal file name, while for
804 	 * regular files, we want to use the real path.
805 	 */
806 	if (-1 == lstat(file, &st)) {
807 		exitcode = (int)MANDOCLEVEL_BADARG;
808 		say(file, "&lstat");
809 		return;
810 	} else if (0 == ((S_IFREG | S_IFLNK) & st.st_mode)) {
811 		exitcode = (int)MANDOCLEVEL_BADARG;
812 		say(file, "Not a regular file");
813 		return;
814 	}
815 
816 	/*
817 	 * We have to resolve the file name to the real path
818 	 * in any case for the base directory check.
819 	 */
820 	if (NULL == realpath(file, buf)) {
821 		exitcode = (int)MANDOCLEVEL_BADARG;
822 		say(file, "&realpath");
823 		return;
824 	}
825 
826 	if (OP_TEST == op)
827 		start = buf;
828 	else if (strstr(buf, basedir) == buf)
829 		start = buf + strlen(basedir);
830 #ifdef HOMEBREWDIR
831 	else if (strstr(buf, HOMEBREWDIR) == buf)
832 		start = buf;
833 #endif
834 	else {
835 		exitcode = (int)MANDOCLEVEL_BADARG;
836 		say("", "%s: outside base directory", buf);
837 		return;
838 	}
839 
840 	/*
841 	 * Now we are sure the file is inside our tree.
842 	 * If it is a symbolic link, ignore the real path
843 	 * and use the original name.
844 	 * This implies passing stuff like "cat1/../man1/foo.1"
845 	 * on the command line won't work.  So don't do that.
846 	 * Note the stat(2) can still fail if the link target
847 	 * doesn't exist.
848 	 */
849 	if (S_IFLNK & st.st_mode) {
850 		if (-1 == stat(buf, &st)) {
851 			exitcode = (int)MANDOCLEVEL_BADARG;
852 			say(file, "&stat");
853 			return;
854 		}
855 		if (strlcpy(buf, file, sizeof(buf)) >= sizeof(buf)) {
856 			say(file, "Filename too long");
857 			return;
858 		}
859 		start = buf;
860 		if (OP_TEST != op && strstr(buf, basedir) == buf)
861 			start += strlen(basedir);
862 	}
863 
864 	mlink = mandoc_calloc(1, sizeof(struct mlink));
865 	mlink->dform = FORM_NONE;
866 	if (strlcpy(mlink->file, start, sizeof(mlink->file)) >=
867 	    sizeof(mlink->file)) {
868 		say(start, "Filename too long");
869 		free(mlink);
870 		return;
871 	}
872 
873 	/*
874 	 * In test mode or when the original name is absolute
875 	 * but outside our tree, guess the base directory.
876 	 */
877 
878 	if (op == OP_TEST || (start == buf && *start == '/')) {
879 		if (strncmp(buf, "man/", 4) == 0)
880 			start = buf + 4;
881 		else if ((start = strstr(buf, "/man/")) != NULL)
882 			start += 5;
883 		else
884 			start = buf;
885 	}
886 
887 	/*
888 	 * First try to guess our directory structure.
889 	 * If we find a separator, try to look for man* or cat*.
890 	 * If we find one of these and what's underneath is a directory,
891 	 * assume it's an architecture.
892 	 */
893 	if (NULL != (p = strchr(start, '/'))) {
894 		*p++ = '\0';
895 		if (0 == strncmp(start, "man", 3)) {
896 			mlink->dform = FORM_SRC;
897 			mlink->dsec = start + 3;
898 		} else if (0 == strncmp(start, "cat", 3)) {
899 			mlink->dform = FORM_CAT;
900 			mlink->dsec = start + 3;
901 		}
902 
903 		start = p;
904 		if (NULL != mlink->dsec && NULL != (p = strchr(start, '/'))) {
905 			*p++ = '\0';
906 			mlink->arch = start;
907 			start = p;
908 		}
909 	}
910 
911 	/*
912 	 * Now check the file suffix.
913 	 * Suffix of `.0' indicates a catpage, `.1-9' is a manpage.
914 	 */
915 	p = strrchr(start, '\0');
916 	while (p-- > start && '/' != *p && '.' != *p)
917 		/* Loop. */ ;
918 
919 	if ('.' == *p) {
920 		*p++ = '\0';
921 		mlink->fsec = p;
922 	}
923 
924 	/*
925 	 * Now try to parse the name.
926 	 * Use the filename portion of the path.
927 	 */
928 	mlink->name = start;
929 	if (NULL != (p = strrchr(start, '/'))) {
930 		mlink->name = p + 1;
931 		*p = '\0';
932 	}
933 	mlink_add(mlink, &st);
934 }
935 
936 static void
937 mlink_add(struct mlink *mlink, const struct stat *st)
938 {
939 	struct inodev	 inodev;
940 	struct mpage	*mpage;
941 	unsigned int	 slot;
942 
943 	assert(NULL != mlink->file);
944 
945 	mlink->dsec = mandoc_strdup(mlink->dsec ? mlink->dsec : "");
946 	mlink->arch = mandoc_strdup(mlink->arch ? mlink->arch : "");
947 	mlink->name = mandoc_strdup(mlink->name ? mlink->name : "");
948 	mlink->fsec = mandoc_strdup(mlink->fsec ? mlink->fsec : "");
949 
950 	if ('0' == *mlink->fsec) {
951 		free(mlink->fsec);
952 		mlink->fsec = mandoc_strdup(mlink->dsec);
953 		mlink->fform = FORM_CAT;
954 	} else if ('1' <= *mlink->fsec && '9' >= *mlink->fsec)
955 		mlink->fform = FORM_SRC;
956 	else
957 		mlink->fform = FORM_NONE;
958 
959 	slot = ohash_qlookup(&mlinks, mlink->file);
960 	assert(NULL == ohash_find(&mlinks, slot));
961 	ohash_insert(&mlinks, slot, mlink);
962 
963 	memset(&inodev, 0, sizeof(inodev));  /* Clear padding. */
964 	inodev.st_ino = st->st_ino;
965 	inodev.st_dev = st->st_dev;
966 	slot = ohash_lookup_memory(&mpages, (char *)&inodev,
967 	    sizeof(struct inodev), inodev.st_ino);
968 	mpage = ohash_find(&mpages, slot);
969 	if (NULL == mpage) {
970 		mpage = mandoc_calloc(1, sizeof(struct mpage));
971 		mpage->inodev.st_ino = inodev.st_ino;
972 		mpage->inodev.st_dev = inodev.st_dev;
973 		mpage->form = FORM_NONE;
974 		mpage->next = mpage_head;
975 		mpage_head = mpage;
976 		ohash_insert(&mpages, slot, mpage);
977 	} else
978 		mlink->next = mpage->mlinks;
979 	mpage->mlinks = mlink;
980 	mlink->mpage = mpage;
981 }
982 
983 static void
984 mlink_free(struct mlink *mlink)
985 {
986 
987 	free(mlink->dsec);
988 	free(mlink->arch);
989 	free(mlink->name);
990 	free(mlink->fsec);
991 	free(mlink);
992 }
993 
994 static void
995 mpages_free(void)
996 {
997 	struct mpage	*mpage;
998 	struct mlink	*mlink;
999 
1000 	while ((mpage = mpage_head) != NULL) {
1001 		while ((mlink = mpage->mlinks) != NULL) {
1002 			mpage->mlinks = mlink->next;
1003 			mlink_free(mlink);
1004 		}
1005 		mpage_head = mpage->next;
1006 		free(mpage->sec);
1007 		free(mpage->arch);
1008 		free(mpage->title);
1009 		free(mpage->desc);
1010 		free(mpage);
1011 	}
1012 }
1013 
1014 /*
1015  * For each mlink to the mpage, check whether the path looks like
1016  * it is formatted, and if it does, check whether a source manual
1017  * exists by the same name, ignoring the suffix.
1018  * If both conditions hold, drop the mlink.
1019  */
1020 static void
1021 mlinks_undupe(struct mpage *mpage)
1022 {
1023 	char		  buf[PATH_MAX];
1024 	struct mlink	**prev;
1025 	struct mlink	 *mlink;
1026 	char		 *bufp;
1027 
1028 	mpage->form = FORM_CAT;
1029 	prev = &mpage->mlinks;
1030 	while (NULL != (mlink = *prev)) {
1031 		if (FORM_CAT != mlink->dform) {
1032 			mpage->form = FORM_NONE;
1033 			goto nextlink;
1034 		}
1035 		(void)strlcpy(buf, mlink->file, sizeof(buf));
1036 		bufp = strstr(buf, "cat");
1037 		assert(NULL != bufp);
1038 		memcpy(bufp, "man", 3);
1039 		if (NULL != (bufp = strrchr(buf, '.')))
1040 			*++bufp = '\0';
1041 		(void)strlcat(buf, mlink->dsec, sizeof(buf));
1042 		if (NULL == ohash_find(&mlinks,
1043 		    ohash_qlookup(&mlinks, buf)))
1044 			goto nextlink;
1045 		if (warnings)
1046 			say(mlink->file, "Man source exists: %s", buf);
1047 		if (use_all)
1048 			goto nextlink;
1049 		*prev = mlink->next;
1050 		mlink_free(mlink);
1051 		continue;
1052 nextlink:
1053 		prev = &(*prev)->next;
1054 	}
1055 }
1056 
1057 static void
1058 mlink_check(struct mpage *mpage, struct mlink *mlink)
1059 {
1060 	struct str	*str;
1061 	unsigned int	 slot;
1062 
1063 	/*
1064 	 * Check whether the manual section given in a file
1065 	 * agrees with the directory where the file is located.
1066 	 * Some manuals have suffixes like (3p) on their
1067 	 * section number either inside the file or in the
1068 	 * directory name, some are linked into more than one
1069 	 * section, like encrypt(1) = makekey(8).
1070 	 */
1071 
1072 	if (FORM_SRC == mpage->form &&
1073 	    strcasecmp(mpage->sec, mlink->dsec))
1074 		say(mlink->file, "Section \"%s\" manual in %s directory",
1075 		    mpage->sec, mlink->dsec);
1076 
1077 	/*
1078 	 * Manual page directories exist for each kernel
1079 	 * architecture as returned by machine(1).
1080 	 * However, many manuals only depend on the
1081 	 * application architecture as returned by arch(1).
1082 	 * For example, some (2/ARM) manuals are shared
1083 	 * across the "armish" and "zaurus" kernel
1084 	 * architectures.
1085 	 * A few manuals are even shared across completely
1086 	 * different architectures, for example fdformat(1)
1087 	 * on amd64, i386, and sparc64.
1088 	 */
1089 
1090 	if (strcasecmp(mpage->arch, mlink->arch))
1091 		say(mlink->file, "Architecture \"%s\" manual in "
1092 		    "\"%s\" directory", mpage->arch, mlink->arch);
1093 
1094 	/*
1095 	 * XXX
1096 	 * parse_cat() doesn't set NAME_TITLE yet.
1097 	 */
1098 
1099 	if (FORM_CAT == mpage->form)
1100 		return;
1101 
1102 	/*
1103 	 * Check whether this mlink
1104 	 * appears as a name in the NAME section.
1105 	 */
1106 
1107 	slot = ohash_qlookup(&names, mlink->name);
1108 	str = ohash_find(&names, slot);
1109 	assert(NULL != str);
1110 	if ( ! (NAME_TITLE & str->mask))
1111 		say(mlink->file, "Name missing in NAME section");
1112 }
1113 
1114 /*
1115  * Run through the files in the global vector "mpages"
1116  * and add them to the database specified in "basedir".
1117  *
1118  * This handles the parsing scheme itself, using the cues of directory
1119  * and filename to determine whether the file is parsable or not.
1120  */
1121 static void
1122 mpages_merge(struct dba *dba, struct mparse *mp)
1123 {
1124 	struct mpage		*mpage, *mpage_dest;
1125 	struct mlink		*mlink, *mlink_dest;
1126 	struct roff_man		*man;
1127 	char			*sodest;
1128 	char			*cp;
1129 	int			 fd;
1130 
1131 	for (mpage = mpage_head; mpage != NULL; mpage = mpage->next) {
1132 		mlinks_undupe(mpage);
1133 		if ((mlink = mpage->mlinks) == NULL)
1134 			continue;
1135 
1136 		name_mask = NAME_MASK;
1137 		mandoc_ohash_init(&names, 4, offsetof(struct str, key));
1138 		mandoc_ohash_init(&strings, 6, offsetof(struct str, key));
1139 		mparse_reset(mp);
1140 		man = NULL;
1141 		sodest = NULL;
1142 
1143 		if ((fd = mparse_open(mp, mlink->file)) == -1) {
1144 			say(mlink->file, "&open");
1145 			goto nextpage;
1146 		}
1147 
1148 		/*
1149 		 * Interpret the file as mdoc(7) or man(7) source
1150 		 * code, unless it is known to be formatted.
1151 		 */
1152 		if (mlink->dform != FORM_CAT || mlink->fform != FORM_CAT) {
1153 			mparse_readfd(mp, fd, mlink->file);
1154 			close(fd);
1155 			fd = -1;
1156 			mparse_result(mp, &man, &sodest);
1157 		}
1158 
1159 		if (sodest != NULL) {
1160 			mlink_dest = ohash_find(&mlinks,
1161 			    ohash_qlookup(&mlinks, sodest));
1162 			if (mlink_dest == NULL) {
1163 				mandoc_asprintf(&cp, "%s.gz", sodest);
1164 				mlink_dest = ohash_find(&mlinks,
1165 				    ohash_qlookup(&mlinks, cp));
1166 				free(cp);
1167 			}
1168 			if (mlink_dest != NULL) {
1169 
1170 				/* The .so target exists. */
1171 
1172 				mpage_dest = mlink_dest->mpage;
1173 				while (1) {
1174 					mlink->mpage = mpage_dest;
1175 
1176 					/*
1177 					 * If the target was already
1178 					 * processed, add the links
1179 					 * to the database now.
1180 					 * Otherwise, this will
1181 					 * happen when we come
1182 					 * to the target.
1183 					 */
1184 
1185 					if (mpage_dest->dba != NULL)
1186 						dbadd_mlink(mlink);
1187 
1188 					if (mlink->next == NULL)
1189 						break;
1190 					mlink = mlink->next;
1191 				}
1192 
1193 				/* Move all links to the target. */
1194 
1195 				mlink->next = mlink_dest->next;
1196 				mlink_dest->next = mpage->mlinks;
1197 				mpage->mlinks = NULL;
1198 			}
1199 			goto nextpage;
1200 		} else if (man != NULL && man->macroset == MACROSET_MDOC) {
1201 			mdoc_validate(man);
1202 			mpage->form = FORM_SRC;
1203 			mpage->sec = man->meta.msec;
1204 			mpage->sec = mandoc_strdup(
1205 			    mpage->sec == NULL ? "" : mpage->sec);
1206 			mpage->arch = man->meta.arch;
1207 			mpage->arch = mandoc_strdup(
1208 			    mpage->arch == NULL ? "" : mpage->arch);
1209 			mpage->title = mandoc_strdup(man->meta.title);
1210 		} else if (man != NULL && man->macroset == MACROSET_MAN) {
1211 			man_validate(man);
1212 			if (*man->meta.msec != '\0' ||
1213 			    *man->meta.title != '\0') {
1214 				mpage->form = FORM_SRC;
1215 				mpage->sec = mandoc_strdup(man->meta.msec);
1216 				mpage->arch = mandoc_strdup(mlink->arch);
1217 				mpage->title = mandoc_strdup(man->meta.title);
1218 			} else
1219 				man = NULL;
1220 		}
1221 
1222 		assert(mpage->desc == NULL);
1223 		if (man == NULL) {
1224 			mpage->form = FORM_CAT;
1225 			mpage->sec = mandoc_strdup(mlink->dsec);
1226 			mpage->arch = mandoc_strdup(mlink->arch);
1227 			mpage->title = mandoc_strdup(mlink->name);
1228 			parse_cat(mpage, fd);
1229 		} else if (man->macroset == MACROSET_MDOC)
1230 			parse_mdoc(mpage, &man->meta, man->first);
1231 		else
1232 			parse_man(mpage, &man->meta, man->first);
1233 		if (mpage->desc == NULL) {
1234 			mpage->desc = mandoc_strdup(mlink->name);
1235 			if (warnings)
1236 				say(mlink->file, "No one-line description, "
1237 				    "using filename \"%s\"", mlink->name);
1238 		}
1239 
1240 		for (mlink = mpage->mlinks;
1241 		     mlink != NULL;
1242 		     mlink = mlink->next) {
1243 			putkey(mpage, mlink->name, NAME_FILE);
1244 			if (warnings && !use_all)
1245 				mlink_check(mpage, mlink);
1246 		}
1247 
1248 		dbadd(dba, mpage);
1249 
1250 nextpage:
1251 		ohash_delete(&strings);
1252 		ohash_delete(&names);
1253 	}
1254 }
1255 
1256 static void
1257 parse_cat(struct mpage *mpage, int fd)
1258 {
1259 	FILE		*stream;
1260 	struct mlink	*mlink;
1261 	char		*line, *p, *title, *sec;
1262 	size_t		 linesz, plen, titlesz;
1263 	ssize_t		 len;
1264 	int		 offs;
1265 
1266 	mlink = mpage->mlinks;
1267 	stream = fd == -1 ? fopen(mlink->file, "r") : fdopen(fd, "r");
1268 	if (stream == NULL) {
1269 		if (fd != -1)
1270 			close(fd);
1271 		if (warnings)
1272 			say(mlink->file, "&fopen");
1273 		return;
1274 	}
1275 
1276 	line = NULL;
1277 	linesz = 0;
1278 
1279 	/* Parse the section number from the header line. */
1280 
1281 	while (getline(&line, &linesz, stream) != -1) {
1282 		if (*line == '\n')
1283 			continue;
1284 		if ((sec = strchr(line, '(')) == NULL)
1285 			break;
1286 		if ((p = strchr(++sec, ')')) == NULL)
1287 			break;
1288 		free(mpage->sec);
1289 		mpage->sec = mandoc_strndup(sec, p - sec);
1290 		if (warnings && *mlink->dsec != '\0' &&
1291 		    strcasecmp(mpage->sec, mlink->dsec))
1292 			say(mlink->file,
1293 			    "Section \"%s\" manual in %s directory",
1294 			    mpage->sec, mlink->dsec);
1295 		break;
1296 	}
1297 
1298 	/* Skip to first blank line. */
1299 
1300 	while (line == NULL || *line != '\n')
1301 		if (getline(&line, &linesz, stream) == -1)
1302 			break;
1303 
1304 	/*
1305 	 * Assume the first line that is not indented
1306 	 * is the first section header.  Skip to it.
1307 	 */
1308 
1309 	while (getline(&line, &linesz, stream) != -1)
1310 		if (*line != '\n' && *line != ' ')
1311 			break;
1312 
1313 	/*
1314 	 * Read up until the next section into a buffer.
1315 	 * Strip the leading and trailing newline from each read line,
1316 	 * appending a trailing space.
1317 	 * Ignore empty (whitespace-only) lines.
1318 	 */
1319 
1320 	titlesz = 0;
1321 	title = NULL;
1322 
1323 	while ((len = getline(&line, &linesz, stream)) != -1) {
1324 		if (*line != ' ')
1325 			break;
1326 		offs = 0;
1327 		while (isspace((unsigned char)line[offs]))
1328 			offs++;
1329 		if (line[offs] == '\0')
1330 			continue;
1331 		title = mandoc_realloc(title, titlesz + len - offs);
1332 		memcpy(title + titlesz, line + offs, len - offs);
1333 		titlesz += len - offs;
1334 		title[titlesz - 1] = ' ';
1335 	}
1336 	free(line);
1337 
1338 	/*
1339 	 * If no page content can be found, or the input line
1340 	 * is already the next section header, or there is no
1341 	 * trailing newline, reuse the page title as the page
1342 	 * description.
1343 	 */
1344 
1345 	if (NULL == title || '\0' == *title) {
1346 		if (warnings)
1347 			say(mlink->file, "Cannot find NAME section");
1348 		fclose(stream);
1349 		free(title);
1350 		return;
1351 	}
1352 
1353 	title[titlesz - 1] = '\0';
1354 
1355 	/*
1356 	 * Skip to the first dash.
1357 	 * Use the remaining line as the description (no more than 70
1358 	 * bytes).
1359 	 */
1360 
1361 	if (NULL != (p = strstr(title, "- "))) {
1362 		for (p += 2; ' ' == *p || '\b' == *p; p++)
1363 			/* Skip to next word. */ ;
1364 	} else {
1365 		if (warnings)
1366 			say(mlink->file, "No dash in title line, "
1367 			    "reusing \"%s\" as one-line description", title);
1368 		p = title;
1369 	}
1370 
1371 	plen = strlen(p);
1372 
1373 	/* Strip backspace-encoding from line. */
1374 
1375 	while (NULL != (line = memchr(p, '\b', plen))) {
1376 		len = line - p;
1377 		if (0 == len) {
1378 			memmove(line, line + 1, plen--);
1379 			continue;
1380 		}
1381 		memmove(line - 1, line + 1, plen - len);
1382 		plen -= 2;
1383 	}
1384 
1385 	mpage->desc = mandoc_strdup(p);
1386 	fclose(stream);
1387 	free(title);
1388 }
1389 
1390 /*
1391  * Put a type/word pair into the word database for this particular file.
1392  */
1393 static void
1394 putkey(const struct mpage *mpage, char *value, uint64_t type)
1395 {
1396 	putkeys(mpage, value, strlen(value), type);
1397 }
1398 
1399 /*
1400  * Grok all nodes at or below a certain mdoc node into putkey().
1401  */
1402 static void
1403 putmdockey(const struct mpage *mpage,
1404 	const struct roff_node *n, uint64_t m, int taboo)
1405 {
1406 
1407 	for ( ; NULL != n; n = n->next) {
1408 		if (n->flags & taboo)
1409 			continue;
1410 		if (NULL != n->child)
1411 			putmdockey(mpage, n->child, m, taboo);
1412 		if (n->type == ROFFT_TEXT)
1413 			putkey(mpage, n->string, m);
1414 	}
1415 }
1416 
1417 static void
1418 parse_man(struct mpage *mpage, const struct roff_meta *meta,
1419 	const struct roff_node *n)
1420 {
1421 	const struct roff_node *head, *body;
1422 	char		*start, *title;
1423 	char		 byte;
1424 	size_t		 sz;
1425 
1426 	if (n == NULL)
1427 		return;
1428 
1429 	/*
1430 	 * We're only searching for one thing: the first text child in
1431 	 * the BODY of a NAME section.  Since we don't keep track of
1432 	 * sections in -man, run some hoops to find out whether we're in
1433 	 * the correct section or not.
1434 	 */
1435 
1436 	if (n->type == ROFFT_BODY && n->tok == MAN_SH) {
1437 		body = n;
1438 		if ((head = body->parent->head) != NULL &&
1439 		    (head = head->child) != NULL &&
1440 		    head->next == NULL &&
1441 		    head->type == ROFFT_TEXT &&
1442 		    strcmp(head->string, "NAME") == 0 &&
1443 		    body->child != NULL) {
1444 
1445 			/*
1446 			 * Suck the entire NAME section into memory.
1447 			 * Yes, we might run away.
1448 			 * But too many manuals have big, spread-out
1449 			 * NAME sections over many lines.
1450 			 */
1451 
1452 			title = NULL;
1453 			deroff(&title, body);
1454 			if (NULL == title)
1455 				return;
1456 
1457 			/*
1458 			 * Go through a special heuristic dance here.
1459 			 * Conventionally, one or more manual names are
1460 			 * comma-specified prior to a whitespace, then a
1461 			 * dash, then a description.  Try to puzzle out
1462 			 * the name parts here.
1463 			 */
1464 
1465 			start = title;
1466 			for ( ;; ) {
1467 				sz = strcspn(start, " ,");
1468 				if ('\0' == start[sz])
1469 					break;
1470 
1471 				byte = start[sz];
1472 				start[sz] = '\0';
1473 
1474 				/*
1475 				 * Assume a stray trailing comma in the
1476 				 * name list if a name begins with a dash.
1477 				 */
1478 
1479 				if ('-' == start[0] ||
1480 				    ('\\' == start[0] && '-' == start[1]))
1481 					break;
1482 
1483 				putkey(mpage, start, NAME_TITLE);
1484 				if ( ! (mpage->name_head_done ||
1485 				    strcasecmp(start, meta->title))) {
1486 					putkey(mpage, start, NAME_HEAD);
1487 					mpage->name_head_done = 1;
1488 				}
1489 
1490 				if (' ' == byte) {
1491 					start += sz + 1;
1492 					break;
1493 				}
1494 
1495 				assert(',' == byte);
1496 				start += sz + 1;
1497 				while (' ' == *start)
1498 					start++;
1499 			}
1500 
1501 			if (start == title) {
1502 				putkey(mpage, start, NAME_TITLE);
1503 				if ( ! (mpage->name_head_done ||
1504 				    strcasecmp(start, meta->title))) {
1505 					putkey(mpage, start, NAME_HEAD);
1506 					mpage->name_head_done = 1;
1507 				}
1508 				free(title);
1509 				return;
1510 			}
1511 
1512 			while (isspace((unsigned char)*start))
1513 				start++;
1514 
1515 			if (0 == strncmp(start, "-", 1))
1516 				start += 1;
1517 			else if (0 == strncmp(start, "\\-\\-", 4))
1518 				start += 4;
1519 			else if (0 == strncmp(start, "\\-", 2))
1520 				start += 2;
1521 			else if (0 == strncmp(start, "\\(en", 4))
1522 				start += 4;
1523 			else if (0 == strncmp(start, "\\(em", 4))
1524 				start += 4;
1525 
1526 			while (' ' == *start)
1527 				start++;
1528 
1529 			mpage->desc = mandoc_strdup(start);
1530 			free(title);
1531 			return;
1532 		}
1533 	}
1534 
1535 	for (n = n->child; n; n = n->next) {
1536 		if (NULL != mpage->desc)
1537 			break;
1538 		parse_man(mpage, meta, n);
1539 	}
1540 }
1541 
1542 static void
1543 parse_mdoc(struct mpage *mpage, const struct roff_meta *meta,
1544 	const struct roff_node *n)
1545 {
1546 
1547 	for (n = n->child; n != NULL; n = n->next) {
1548 		if (n->tok == TOKEN_NONE ||
1549 		    n->tok < ROFF_MAX ||
1550 		    n->flags & mdocs[n->tok].taboo)
1551 			continue;
1552 		assert(n->tok >= MDOC_Dd && n->tok < MDOC_MAX);
1553 		switch (n->type) {
1554 		case ROFFT_ELEM:
1555 		case ROFFT_BLOCK:
1556 		case ROFFT_HEAD:
1557 		case ROFFT_BODY:
1558 		case ROFFT_TAIL:
1559 			if (mdocs[n->tok].fp != NULL &&
1560 			    (*mdocs[n->tok].fp)(mpage, meta, n) == 0)
1561 				break;
1562 			if (mdocs[n->tok].mask)
1563 				putmdockey(mpage, n->child,
1564 				    mdocs[n->tok].mask, mdocs[n->tok].taboo);
1565 			break;
1566 		default:
1567 			continue;
1568 		}
1569 		if (NULL != n->child)
1570 			parse_mdoc(mpage, meta, n);
1571 	}
1572 }
1573 
1574 static int
1575 parse_mdoc_Fd(struct mpage *mpage, const struct roff_meta *meta,
1576 	const struct roff_node *n)
1577 {
1578 	char		*start, *end;
1579 	size_t		 sz;
1580 
1581 	if (SEC_SYNOPSIS != n->sec ||
1582 	    NULL == (n = n->child) ||
1583 	    n->type != ROFFT_TEXT)
1584 		return 0;
1585 
1586 	/*
1587 	 * Only consider those `Fd' macro fields that begin with an
1588 	 * "inclusion" token (versus, e.g., #define).
1589 	 */
1590 
1591 	if (strcmp("#include", n->string))
1592 		return 0;
1593 
1594 	if ((n = n->next) == NULL || n->type != ROFFT_TEXT)
1595 		return 0;
1596 
1597 	/*
1598 	 * Strip away the enclosing angle brackets and make sure we're
1599 	 * not zero-length.
1600 	 */
1601 
1602 	start = n->string;
1603 	if ('<' == *start || '"' == *start)
1604 		start++;
1605 
1606 	if (0 == (sz = strlen(start)))
1607 		return 0;
1608 
1609 	end = &start[(int)sz - 1];
1610 	if ('>' == *end || '"' == *end)
1611 		end--;
1612 
1613 	if (end > start)
1614 		putkeys(mpage, start, end - start + 1, TYPE_In);
1615 	return 0;
1616 }
1617 
1618 static void
1619 parse_mdoc_fname(struct mpage *mpage, const struct roff_node *n)
1620 {
1621 	char	*cp;
1622 	size_t	 sz;
1623 
1624 	if (n->type != ROFFT_TEXT)
1625 		return;
1626 
1627 	/* Skip function pointer punctuation. */
1628 
1629 	cp = n->string;
1630 	while (*cp == '(' || *cp == '*')
1631 		cp++;
1632 	sz = strcspn(cp, "()");
1633 
1634 	putkeys(mpage, cp, sz, TYPE_Fn);
1635 	if (n->sec == SEC_SYNOPSIS)
1636 		putkeys(mpage, cp, sz, NAME_SYN);
1637 }
1638 
1639 static int
1640 parse_mdoc_Fn(struct mpage *mpage, const struct roff_meta *meta,
1641 	const struct roff_node *n)
1642 {
1643 
1644 	if (n->child == NULL)
1645 		return 0;
1646 
1647 	parse_mdoc_fname(mpage, n->child);
1648 
1649 	for (n = n->child->next; n != NULL; n = n->next)
1650 		if (n->type == ROFFT_TEXT)
1651 			putkey(mpage, n->string, TYPE_Fa);
1652 
1653 	return 0;
1654 }
1655 
1656 static int
1657 parse_mdoc_Fo(struct mpage *mpage, const struct roff_meta *meta,
1658 	const struct roff_node *n)
1659 {
1660 
1661 	if (n->type != ROFFT_HEAD)
1662 		return 1;
1663 
1664 	if (n->child != NULL)
1665 		parse_mdoc_fname(mpage, n->child);
1666 
1667 	return 0;
1668 }
1669 
1670 static int
1671 parse_mdoc_Va(struct mpage *mpage, const struct roff_meta *meta,
1672 	const struct roff_node *n)
1673 {
1674 	char *cp;
1675 
1676 	if (n->type != ROFFT_ELEM && n->type != ROFFT_BODY)
1677 		return 0;
1678 
1679 	if (n->child != NULL &&
1680 	    n->child->next == NULL &&
1681 	    n->child->type == ROFFT_TEXT)
1682 		return 1;
1683 
1684 	cp = NULL;
1685 	deroff(&cp, n);
1686 	if (cp != NULL) {
1687 		putkey(mpage, cp, TYPE_Vt | (n->tok == MDOC_Va ||
1688 		    n->type == ROFFT_BODY ? TYPE_Va : 0));
1689 		free(cp);
1690 	}
1691 
1692 	return 0;
1693 }
1694 
1695 static int
1696 parse_mdoc_Xr(struct mpage *mpage, const struct roff_meta *meta,
1697 	const struct roff_node *n)
1698 {
1699 	char	*cp;
1700 
1701 	if (NULL == (n = n->child))
1702 		return 0;
1703 
1704 	if (NULL == n->next) {
1705 		putkey(mpage, n->string, TYPE_Xr);
1706 		return 0;
1707 	}
1708 
1709 	mandoc_asprintf(&cp, "%s(%s)", n->string, n->next->string);
1710 	putkey(mpage, cp, TYPE_Xr);
1711 	free(cp);
1712 	return 0;
1713 }
1714 
1715 static int
1716 parse_mdoc_Nd(struct mpage *mpage, const struct roff_meta *meta,
1717 	const struct roff_node *n)
1718 {
1719 
1720 	if (n->type == ROFFT_BODY)
1721 		deroff(&mpage->desc, n);
1722 	return 0;
1723 }
1724 
1725 static int
1726 parse_mdoc_Nm(struct mpage *mpage, const struct roff_meta *meta,
1727 	const struct roff_node *n)
1728 {
1729 
1730 	if (SEC_NAME == n->sec)
1731 		putmdockey(mpage, n->child, NAME_TITLE, 0);
1732 	else if (n->sec == SEC_SYNOPSIS && n->type == ROFFT_HEAD) {
1733 		if (n->child == NULL)
1734 			putkey(mpage, meta->name, NAME_SYN);
1735 		else
1736 			putmdockey(mpage, n->child, NAME_SYN, 0);
1737 	}
1738 	if ( ! (mpage->name_head_done ||
1739 	    n->child == NULL || n->child->string == NULL ||
1740 	    strcasecmp(n->child->string, meta->title))) {
1741 		putkey(mpage, n->child->string, NAME_HEAD);
1742 		mpage->name_head_done = 1;
1743 	}
1744 	return 0;
1745 }
1746 
1747 static int
1748 parse_mdoc_Sh(struct mpage *mpage, const struct roff_meta *meta,
1749 	const struct roff_node *n)
1750 {
1751 
1752 	return n->sec == SEC_CUSTOM && n->type == ROFFT_HEAD;
1753 }
1754 
1755 static int
1756 parse_mdoc_head(struct mpage *mpage, const struct roff_meta *meta,
1757 	const struct roff_node *n)
1758 {
1759 
1760 	return n->type == ROFFT_HEAD;
1761 }
1762 
1763 /*
1764  * Add a string to the hash table for the current manual.
1765  * Each string has a bitmask telling which macros it belongs to.
1766  * When we finish the manual, we'll dump the table.
1767  */
1768 static void
1769 putkeys(const struct mpage *mpage, char *cp, size_t sz, uint64_t v)
1770 {
1771 	struct ohash	*htab;
1772 	struct str	*s;
1773 	const char	*end;
1774 	unsigned int	 slot;
1775 	int		 i, mustfree;
1776 
1777 	if (0 == sz)
1778 		return;
1779 
1780 	mustfree = render_string(&cp, &sz);
1781 
1782 	if (TYPE_Nm & v) {
1783 		htab = &names;
1784 		v &= name_mask;
1785 		if (v & NAME_FIRST)
1786 			name_mask &= ~NAME_FIRST;
1787 		if (debug > 1)
1788 			say(mpage->mlinks->file,
1789 			    "Adding name %*s, bits=0x%llx", (int)sz, cp,
1790 			    (unsigned long long)v);
1791 	} else {
1792 		htab = &strings;
1793 		if (debug > 1)
1794 		    for (i = 0; i < KEY_MAX; i++)
1795 			if ((uint64_t)1 << i & v)
1796 			    say(mpage->mlinks->file,
1797 				"Adding key %s=%*s",
1798 				mansearch_keynames[i], (int)sz, cp);
1799 	}
1800 
1801 	end = cp + sz;
1802 	slot = ohash_qlookupi(htab, cp, &end);
1803 	s = ohash_find(htab, slot);
1804 
1805 	if (NULL != s && mpage == s->mpage) {
1806 		s->mask |= v;
1807 		return;
1808 	} else if (NULL == s) {
1809 		s = mandoc_calloc(1, sizeof(struct str) + sz + 1);
1810 		memcpy(s->key, cp, sz);
1811 		ohash_insert(htab, slot, s);
1812 	}
1813 	s->mpage = mpage;
1814 	s->mask = v;
1815 
1816 	if (mustfree)
1817 		free(cp);
1818 }
1819 
1820 /*
1821  * Take a Unicode codepoint and produce its UTF-8 encoding.
1822  * This isn't the best way to do this, but it works.
1823  * The magic numbers are from the UTF-8 packaging.
1824  * They're not as scary as they seem: read the UTF-8 spec for details.
1825  */
1826 static size_t
1827 utf8(unsigned int cp, char out[7])
1828 {
1829 	size_t		 rc;
1830 
1831 	rc = 0;
1832 	if (cp <= 0x0000007F) {
1833 		rc = 1;
1834 		out[0] = (char)cp;
1835 	} else if (cp <= 0x000007FF) {
1836 		rc = 2;
1837 		out[0] = (cp >> 6  & 31) | 192;
1838 		out[1] = (cp       & 63) | 128;
1839 	} else if (cp <= 0x0000FFFF) {
1840 		rc = 3;
1841 		out[0] = (cp >> 12 & 15) | 224;
1842 		out[1] = (cp >> 6  & 63) | 128;
1843 		out[2] = (cp       & 63) | 128;
1844 	} else if (cp <= 0x001FFFFF) {
1845 		rc = 4;
1846 		out[0] = (cp >> 18 &  7) | 240;
1847 		out[1] = (cp >> 12 & 63) | 128;
1848 		out[2] = (cp >> 6  & 63) | 128;
1849 		out[3] = (cp       & 63) | 128;
1850 	} else if (cp <= 0x03FFFFFF) {
1851 		rc = 5;
1852 		out[0] = (cp >> 24 &  3) | 248;
1853 		out[1] = (cp >> 18 & 63) | 128;
1854 		out[2] = (cp >> 12 & 63) | 128;
1855 		out[3] = (cp >> 6  & 63) | 128;
1856 		out[4] = (cp       & 63) | 128;
1857 	} else if (cp <= 0x7FFFFFFF) {
1858 		rc = 6;
1859 		out[0] = (cp >> 30 &  1) | 252;
1860 		out[1] = (cp >> 24 & 63) | 128;
1861 		out[2] = (cp >> 18 & 63) | 128;
1862 		out[3] = (cp >> 12 & 63) | 128;
1863 		out[4] = (cp >> 6  & 63) | 128;
1864 		out[5] = (cp       & 63) | 128;
1865 	} else
1866 		return 0;
1867 
1868 	out[rc] = '\0';
1869 	return rc;
1870 }
1871 
1872 /*
1873  * If the string contains escape sequences,
1874  * replace it with an allocated rendering and return 1,
1875  * such that the caller can free it after use.
1876  * Otherwise, do nothing and return 0.
1877  */
1878 static int
1879 render_string(char **public, size_t *psz)
1880 {
1881 	const char	*src, *scp, *addcp, *seq;
1882 	char		*dst;
1883 	size_t		 ssz, dsz, addsz;
1884 	char		 utfbuf[7], res[6];
1885 	int		 seqlen, unicode;
1886 
1887 	res[0] = '\\';
1888 	res[1] = '\t';
1889 	res[2] = ASCII_NBRSP;
1890 	res[3] = ASCII_HYPH;
1891 	res[4] = ASCII_BREAK;
1892 	res[5] = '\0';
1893 
1894 	src = scp = *public;
1895 	ssz = *psz;
1896 	dst = NULL;
1897 	dsz = 0;
1898 
1899 	while (scp < src + *psz) {
1900 
1901 		/* Leave normal characters unchanged. */
1902 
1903 		if (strchr(res, *scp) == NULL) {
1904 			if (dst != NULL)
1905 				dst[dsz++] = *scp;
1906 			scp++;
1907 			continue;
1908 		}
1909 
1910 		/*
1911 		 * Found something that requires replacing,
1912 		 * make sure we have a destination buffer.
1913 		 */
1914 
1915 		if (dst == NULL) {
1916 			dst = mandoc_malloc(ssz + 1);
1917 			dsz = scp - src;
1918 			memcpy(dst, src, dsz);
1919 		}
1920 
1921 		/* Handle single-char special characters. */
1922 
1923 		switch (*scp) {
1924 		case '\\':
1925 			break;
1926 		case '\t':
1927 		case ASCII_NBRSP:
1928 			dst[dsz++] = ' ';
1929 			scp++;
1930 			continue;
1931 		case ASCII_HYPH:
1932 			dst[dsz++] = '-';
1933 			/* FALLTHROUGH */
1934 		case ASCII_BREAK:
1935 			scp++;
1936 			continue;
1937 		default:
1938 			abort();
1939 		}
1940 
1941 		/*
1942 		 * Found an escape sequence.
1943 		 * Read past the slash, then parse it.
1944 		 * Ignore everything except characters.
1945 		 */
1946 
1947 		scp++;
1948 		if (mandoc_escape(&scp, &seq, &seqlen) != ESCAPE_SPECIAL)
1949 			continue;
1950 
1951 		/*
1952 		 * Render the special character
1953 		 * as either UTF-8 or ASCII.
1954 		 */
1955 
1956 		if (write_utf8) {
1957 			unicode = mchars_spec2cp(seq, seqlen);
1958 			if (unicode <= 0)
1959 				continue;
1960 			addsz = utf8(unicode, utfbuf);
1961 			if (addsz == 0)
1962 				continue;
1963 			addcp = utfbuf;
1964 		} else {
1965 			addcp = mchars_spec2str(seq, seqlen, &addsz);
1966 			if (addcp == NULL)
1967 				continue;
1968 			if (*addcp == ASCII_NBRSP) {
1969 				addcp = " ";
1970 				addsz = 1;
1971 			}
1972 		}
1973 
1974 		/* Copy the rendered glyph into the stream. */
1975 
1976 		ssz += addsz;
1977 		dst = mandoc_realloc(dst, ssz + 1);
1978 		memcpy(dst + dsz, addcp, addsz);
1979 		dsz += addsz;
1980 	}
1981 	if (dst != NULL) {
1982 		*public = dst;
1983 		*psz = dsz;
1984 	}
1985 
1986 	/* Trim trailing whitespace and NUL-terminate. */
1987 
1988 	while (*psz > 0 && (*public)[*psz - 1] == ' ')
1989 		--*psz;
1990 	if (dst != NULL) {
1991 		(*public)[*psz] = '\0';
1992 		return 1;
1993 	} else
1994 		return 0;
1995 }
1996 
1997 static void
1998 dbadd_mlink(const struct mlink *mlink)
1999 {
2000 	dba_page_alias(mlink->mpage->dba, mlink->name, NAME_FILE);
2001 	dba_page_add(mlink->mpage->dba, DBP_SECT, mlink->dsec);
2002 	dba_page_add(mlink->mpage->dba, DBP_SECT, mlink->fsec);
2003 	dba_page_add(mlink->mpage->dba, DBP_ARCH, mlink->arch);
2004 	dba_page_add(mlink->mpage->dba, DBP_FILE, mlink->file);
2005 }
2006 
2007 /*
2008  * Flush the current page's terms (and their bits) into the database.
2009  * Also, handle escape sequences at the last possible moment.
2010  */
2011 static void
2012 dbadd(struct dba *dba, struct mpage *mpage)
2013 {
2014 	struct mlink	*mlink;
2015 	struct str	*key;
2016 	char		*cp;
2017 	uint64_t	 mask;
2018 	size_t		 i;
2019 	unsigned int	 slot;
2020 	int		 mustfree;
2021 
2022 	mlink = mpage->mlinks;
2023 
2024 	if (nodb) {
2025 		for (key = ohash_first(&names, &slot); NULL != key;
2026 		     key = ohash_next(&names, &slot))
2027 			free(key);
2028 		for (key = ohash_first(&strings, &slot); NULL != key;
2029 		     key = ohash_next(&strings, &slot))
2030 			free(key);
2031 		if (0 == debug)
2032 			return;
2033 		while (NULL != mlink) {
2034 			fputs(mlink->name, stdout);
2035 			if (NULL == mlink->next ||
2036 			    strcmp(mlink->dsec, mlink->next->dsec) ||
2037 			    strcmp(mlink->fsec, mlink->next->fsec) ||
2038 			    strcmp(mlink->arch, mlink->next->arch)) {
2039 				putchar('(');
2040 				if ('\0' == *mlink->dsec)
2041 					fputs(mlink->fsec, stdout);
2042 				else
2043 					fputs(mlink->dsec, stdout);
2044 				if ('\0' != *mlink->arch)
2045 					printf("/%s", mlink->arch);
2046 				putchar(')');
2047 			}
2048 			mlink = mlink->next;
2049 			if (NULL != mlink)
2050 				fputs(", ", stdout);
2051 		}
2052 		printf(" - %s\n", mpage->desc);
2053 		return;
2054 	}
2055 
2056 	if (debug)
2057 		say(mlink->file, "Adding to database");
2058 
2059 	cp = mpage->desc;
2060 	i = strlen(cp);
2061 	mustfree = render_string(&cp, &i);
2062 	mpage->dba = dba_page_new(dba->pages,
2063 	    *mpage->arch == '\0' ? mlink->arch : mpage->arch,
2064 	    cp, mlink->file, mpage->form);
2065 	if (mustfree)
2066 		free(cp);
2067 	dba_page_add(mpage->dba, DBP_SECT, mpage->sec);
2068 
2069 	while (mlink != NULL) {
2070 		dbadd_mlink(mlink);
2071 		mlink = mlink->next;
2072 	}
2073 
2074 	for (key = ohash_first(&names, &slot); NULL != key;
2075 	     key = ohash_next(&names, &slot)) {
2076 		assert(key->mpage == mpage);
2077 		dba_page_alias(mpage->dba, key->key, key->mask);
2078 		free(key);
2079 	}
2080 	for (key = ohash_first(&strings, &slot); NULL != key;
2081 	     key = ohash_next(&strings, &slot)) {
2082 		assert(key->mpage == mpage);
2083 		i = 0;
2084 		for (mask = TYPE_Xr; mask <= TYPE_Lb; mask *= 2) {
2085 			if (key->mask & mask)
2086 				dba_macro_add(dba->macros, i,
2087 				    key->key, mpage->dba);
2088 			i++;
2089 		}
2090 		free(key);
2091 	}
2092 }
2093 
2094 static void
2095 dbprune(struct dba *dba)
2096 {
2097 	struct dba_array	*page, *files;
2098 	char			*file;
2099 
2100 	dba_array_FOREACH(dba->pages, page) {
2101 		files = dba_array_get(page, DBP_FILE);
2102 		dba_array_FOREACH(files, file) {
2103 			if (*file < ' ')
2104 				file++;
2105 			if (ohash_find(&mlinks, ohash_qlookup(&mlinks,
2106 			    file)) != NULL) {
2107 				if (debug)
2108 					say(file, "Deleting from database");
2109 				dba_array_del(dba->pages);
2110 				break;
2111 			}
2112 		}
2113 	}
2114 }
2115 
2116 /*
2117  * Write the database from memory to disk.
2118  */
2119 static void
2120 dbwrite(struct dba *dba)
2121 {
2122 	char		 tfn[32];
2123 	int		 status;
2124 	pid_t		 child;
2125 
2126 	/*
2127 	 * Do not write empty databases, and delete existing ones
2128 	 * when makewhatis -u causes them to become empty.
2129 	 */
2130 
2131 	dba_array_start(dba->pages);
2132 	if (dba_array_next(dba->pages) == NULL) {
2133 		if (unlink(MANDOC_DB) == -1 && errno != ENOENT)
2134 			say(MANDOC_DB, "&unlink");
2135 		return;
2136 	}
2137 
2138 	/*
2139 	 * Build the database in a temporary file,
2140 	 * then atomically move it into place.
2141 	 */
2142 
2143 	if (dba_write(MANDOC_DB "~", dba) != -1) {
2144 		if (rename(MANDOC_DB "~", MANDOC_DB) == -1) {
2145 			exitcode = (int)MANDOCLEVEL_SYSERR;
2146 			say(MANDOC_DB, "&rename");
2147 			unlink(MANDOC_DB "~");
2148 		}
2149 		return;
2150 	}
2151 
2152 	/*
2153 	 * We lack write permission and cannot replace the database
2154 	 * file, but let's at least check whether the data changed.
2155 	 */
2156 
2157 	(void)strlcpy(tfn, "/tmp/mandocdb.XXXXXXXX", sizeof(tfn));
2158 	if (mkdtemp(tfn) == NULL) {
2159 		exitcode = (int)MANDOCLEVEL_SYSERR;
2160 		say("", "&%s", tfn);
2161 		return;
2162 	}
2163 
2164 	(void)strlcat(tfn, "/" MANDOC_DB, sizeof(tfn));
2165 	if (dba_write(tfn, dba) == -1) {
2166 		exitcode = (int)MANDOCLEVEL_SYSERR;
2167 		say(tfn, "&dba_write");
2168 		goto out;
2169 	}
2170 
2171 	switch (child = fork()) {
2172 	case -1:
2173 		exitcode = (int)MANDOCLEVEL_SYSERR;
2174 		say("", "&fork cmp");
2175 		return;
2176 	case 0:
2177 		execlp("cmp", "cmp", "-s", tfn, MANDOC_DB, (char *)NULL);
2178 		say("", "&exec cmp");
2179 		exit(0);
2180 	default:
2181 		break;
2182 	}
2183 	if (waitpid(child, &status, 0) == -1) {
2184 		exitcode = (int)MANDOCLEVEL_SYSERR;
2185 		say("", "&wait cmp");
2186 	} else if (WIFSIGNALED(status)) {
2187 		exitcode = (int)MANDOCLEVEL_SYSERR;
2188 		say("", "cmp died from signal %d", WTERMSIG(status));
2189 	} else if (WEXITSTATUS(status)) {
2190 		exitcode = (int)MANDOCLEVEL_SYSERR;
2191 		say(MANDOC_DB,
2192 		    "Data changed, but cannot replace database");
2193 	}
2194 
2195 out:
2196 	*strrchr(tfn, '/') = '\0';
2197 	switch (child = fork()) {
2198 	case -1:
2199 		exitcode = (int)MANDOCLEVEL_SYSERR;
2200 		say("", "&fork rm");
2201 		return;
2202 	case 0:
2203 		execlp("rm", "rm", "-rf", tfn, (char *)NULL);
2204 		say("", "&exec rm");
2205 		exit((int)MANDOCLEVEL_SYSERR);
2206 	default:
2207 		break;
2208 	}
2209 	if (waitpid(child, &status, 0) == -1) {
2210 		exitcode = (int)MANDOCLEVEL_SYSERR;
2211 		say("", "&wait rm");
2212 	} else if (WIFSIGNALED(status) || WEXITSTATUS(status)) {
2213 		exitcode = (int)MANDOCLEVEL_SYSERR;
2214 		say("", "%s: Cannot remove temporary directory", tfn);
2215 	}
2216 }
2217 
2218 static int
2219 set_basedir(const char *targetdir, int report_baddir)
2220 {
2221 	static char	 startdir[PATH_MAX];
2222 	static int	 getcwd_status;  /* 1 = ok, 2 = failure */
2223 	static int	 chdir_status;  /* 1 = changed directory */
2224 	char		*cp;
2225 
2226 	/*
2227 	 * Remember the original working directory, if possible.
2228 	 * This will be needed if the second or a later directory
2229 	 * on the command line is given as a relative path.
2230 	 * Do not error out if the current directory is not
2231 	 * searchable: Maybe it won't be needed after all.
2232 	 */
2233 	if (0 == getcwd_status) {
2234 		if (NULL == getcwd(startdir, sizeof(startdir))) {
2235 			getcwd_status = 2;
2236 			(void)strlcpy(startdir, strerror(errno),
2237 			    sizeof(startdir));
2238 		} else
2239 			getcwd_status = 1;
2240 	}
2241 
2242 	/*
2243 	 * We are leaving the old base directory.
2244 	 * Do not use it any longer, not even for messages.
2245 	 */
2246 	*basedir = '\0';
2247 
2248 	/*
2249 	 * If and only if the directory was changed earlier and
2250 	 * the next directory to process is given as a relative path,
2251 	 * first go back, or bail out if that is impossible.
2252 	 */
2253 	if (chdir_status && '/' != *targetdir) {
2254 		if (2 == getcwd_status) {
2255 			exitcode = (int)MANDOCLEVEL_SYSERR;
2256 			say("", "getcwd: %s", startdir);
2257 			return 0;
2258 		}
2259 		if (-1 == chdir(startdir)) {
2260 			exitcode = (int)MANDOCLEVEL_SYSERR;
2261 			say("", "&chdir %s", startdir);
2262 			return 0;
2263 		}
2264 	}
2265 
2266 	/*
2267 	 * Always resolve basedir to the canonicalized absolute
2268 	 * pathname and append a trailing slash, such that
2269 	 * we can reliably check whether files are inside.
2270 	 */
2271 	if (NULL == realpath(targetdir, basedir)) {
2272 		if (report_baddir || errno != ENOENT) {
2273 			exitcode = (int)MANDOCLEVEL_BADARG;
2274 			say("", "&%s: realpath", targetdir);
2275 		}
2276 		return 0;
2277 	} else if (-1 == chdir(basedir)) {
2278 		if (report_baddir || errno != ENOENT) {
2279 			exitcode = (int)MANDOCLEVEL_BADARG;
2280 			say("", "&chdir");
2281 		}
2282 		return 0;
2283 	}
2284 	chdir_status = 1;
2285 	cp = strchr(basedir, '\0');
2286 	if ('/' != cp[-1]) {
2287 		if (cp - basedir >= PATH_MAX - 1) {
2288 			exitcode = (int)MANDOCLEVEL_SYSERR;
2289 			say("", "Filename too long");
2290 			return 0;
2291 		}
2292 		*cp++ = '/';
2293 		*cp = '\0';
2294 	}
2295 	return 1;
2296 }
2297 
2298 static void
2299 say(const char *file, const char *format, ...)
2300 {
2301 	va_list		 ap;
2302 	int		 use_errno;
2303 
2304 	if ('\0' != *basedir)
2305 		fprintf(stderr, "%s", basedir);
2306 	if ('\0' != *basedir && '\0' != *file)
2307 		fputc('/', stderr);
2308 	if ('\0' != *file)
2309 		fprintf(stderr, "%s", file);
2310 
2311 	use_errno = 1;
2312 	if (NULL != format) {
2313 		switch (*format) {
2314 		case '&':
2315 			format++;
2316 			break;
2317 		case '\0':
2318 			format = NULL;
2319 			break;
2320 		default:
2321 			use_errno = 0;
2322 			break;
2323 		}
2324 	}
2325 	if (NULL != format) {
2326 		if ('\0' != *basedir || '\0' != *file)
2327 			fputs(": ", stderr);
2328 		va_start(ap, format);
2329 		vfprintf(stderr, format, ap);
2330 		va_end(ap);
2331 	}
2332 	if (use_errno) {
2333 		if ('\0' != *basedir || '\0' != *file || NULL != format)
2334 			fputs(": ", stderr);
2335 		perror(NULL);
2336 	} else
2337 		fputc('\n', stderr);
2338 }
2339