xref: /freebsd/contrib/mandoc/main.c (revision 2e4311906d8c8dc7a7c726345268253bca6d4acc)
1 /* $Id: main.c,v 1.358 2021/09/04 22:38:46 schwarze Exp $ */
2 /*
3  * Copyright (c) 2010-2012, 2014-2021 Ingo Schwarze <schwarze@openbsd.org>
4  * Copyright (c) 2008-2012 Kristaps Dzonsons <kristaps@bsd.lv>
5  * Copyright (c) 2010 Joerg Sonnenberger <joerg@netbsd.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  * Main program for mandoc(1), man(1), apropos(1), whatis(1), and help(1).
20  */
21 #include "config.h"
22 
23 #include <sys/types.h>
24 #include <sys/ioctl.h>
25 #include <sys/param.h>	/* MACHINE */
26 #include <sys/stat.h>
27 #include <sys/wait.h>
28 
29 #include <assert.h>
30 #include <ctype.h>
31 #if HAVE_ERR
32 #include <err.h>
33 #endif
34 #include <errno.h>
35 #include <fcntl.h>
36 #include <glob.h>
37 #include <limits.h>
38 #if HAVE_SANDBOX_INIT
39 #include <sandbox.h>
40 #endif
41 #include <signal.h>
42 #include <stdio.h>
43 #include <stdint.h>
44 #include <stdlib.h>
45 #include <string.h>
46 #include <termios.h>
47 #include <time.h>
48 #include <unistd.h>
49 
50 #include "mandoc_aux.h"
51 #include "mandoc.h"
52 #include "mandoc_xr.h"
53 #include "roff.h"
54 #include "mdoc.h"
55 #include "man.h"
56 #include "mandoc_parse.h"
57 #include "tag.h"
58 #include "term_tag.h"
59 #include "main.h"
60 #include "manconf.h"
61 #include "mansearch.h"
62 
63 enum	outmode {
64 	OUTMODE_DEF = 0,
65 	OUTMODE_FLN,
66 	OUTMODE_LST,
67 	OUTMODE_ALL,
68 	OUTMODE_ONE
69 };
70 
71 enum	outt {
72 	OUTT_ASCII = 0,	/* -Tascii */
73 	OUTT_LOCALE,	/* -Tlocale */
74 	OUTT_UTF8,	/* -Tutf8 */
75 	OUTT_TREE,	/* -Ttree */
76 	OUTT_MAN,	/* -Tman */
77 	OUTT_HTML,	/* -Thtml */
78 	OUTT_MARKDOWN,	/* -Tmarkdown */
79 	OUTT_LINT,	/* -Tlint */
80 	OUTT_PS,	/* -Tps */
81 	OUTT_PDF	/* -Tpdf */
82 };
83 
84 struct	outstate {
85 	struct tag_files *tag_files;	/* Tagging state variables. */
86 	void		 *outdata;	/* data for output */
87 	int		  use_pager;
88 	int		  wstop;	/* stop after a file with a warning */
89 	int		  had_output;	/* Some output was generated. */
90 	enum outt	  outtype;	/* which output to use */
91 };
92 
93 
94 int			  mandocdb(int, char *[]);
95 
96 static	void		  check_xr(struct manpaths *);
97 static	void		  fs_append(char **, size_t, int,
98 				size_t, const char *, enum form,
99 				struct manpage **, size_t *);
100 static	int		  fs_lookup(const struct manpaths *, size_t,
101 				const char *, const char *, const char *,
102 				struct manpage **, size_t *);
103 static	int		  fs_search(const struct mansearch *,
104 				const struct manpaths *, const char *,
105 				struct manpage **, size_t *);
106 static	void		  glob_esc(char **, const char *, const char *);
107 static	void		  outdata_alloc(struct outstate *, struct manoutput *);
108 static	void		  parse(struct mparse *, int, const char *,
109 				struct outstate *, struct manconf *);
110 static	void		  passthrough(int, int);
111 static	void		  process_onefile(struct mparse *, struct manpage *,
112 				int, struct outstate *, struct manconf *);
113 static	void		  run_pager(struct outstate *, char *);
114 static	pid_t		  spawn_pager(struct outstate *, char *);
115 static	void		  usage(enum argmode) __attribute__((__noreturn__));
116 static	int		  woptions(char *, enum mandoc_os *, int *);
117 
118 static	const int sec_prios[] = {1, 4, 5, 8, 6, 3, 7, 2, 9};
119 static	char		  help_arg[] = "help";
120 static	char		 *help_argv[] = {help_arg, NULL};
121 
122 
123 int
124 main(int argc, char *argv[])
125 {
126 	struct manconf	 conf;		/* Manpaths and output options. */
127 	struct outstate	 outst;		/* Output state. */
128 	struct winsize	 ws;		/* Result of ioctl(TIOCGWINSZ). */
129 	struct mansearch search;	/* Search options. */
130 	struct manpage	*res;		/* Complete list of search results. */
131 	struct manpage	*resn;		/* Search results for one name. */
132 	struct mparse	*mp;		/* Opaque parser object. */
133 	const char	*conf_file;	/* -C: alternate config file. */
134 	const char	*os_s;		/* -I: Operating system for display. */
135 	const char	*progname, *sec, *ep;
136 	char		*defpaths;	/* -M: override manpaths. */
137 	char		*auxpaths;	/* -m: additional manpaths. */
138 	char		*oarg;		/* -O: output option string. */
139 	char		*tagarg;	/* -O tag: default value. */
140 	unsigned char	*uc;
141 	size_t		 ressz;		/* Number of elements in res[]. */
142 	size_t		 resnsz;	/* Number of elements in resn[]. */
143 	size_t		 i, ib, ssz;
144 	int		 options;	/* Parser options. */
145 	int		 show_usage;	/* Invalid argument: give up. */
146 	int		 prio, best_prio;
147 	int		 startdir;
148 	int		 c;
149 	enum mandoc_os	 os_e;		/* Check base system conventions. */
150 	enum outmode	 outmode;	/* According to command line. */
151 
152 #if HAVE_PROGNAME
153 	progname = getprogname();
154 #else
155 	if (argc < 1)
156 		progname = mandoc_strdup("mandoc");
157 	else if ((progname = strrchr(argv[0], '/')) == NULL)
158 		progname = argv[0];
159 	else
160 		++progname;
161 	setprogname(progname);
162 #endif
163 
164 	mandoc_msg_setoutfile(stderr);
165 	if (strncmp(progname, "mandocdb", 8) == 0 ||
166 	    strcmp(progname, BINM_MAKEWHATIS) == 0)
167 		return mandocdb(argc, argv);
168 
169 #if HAVE_PLEDGE
170 	if (pledge("stdio rpath wpath cpath tmppath tty proc exec", NULL) == -1) {
171 		mandoc_msg(MANDOCERR_PLEDGE, 0, 0, "%s", strerror(errno));
172 		return mandoc_msg_getrc();
173 	}
174 #endif
175 #if HAVE_SANDBOX_INIT
176 	if (sandbox_init(kSBXProfileNoInternet, SANDBOX_NAMED, NULL) == -1)
177 		errx((int)MANDOCLEVEL_SYSERR, "sandbox_init");
178 #endif
179 
180 	/* Search options. */
181 
182 	memset(&conf, 0, sizeof(conf));
183 	conf_file = NULL;
184 	defpaths = auxpaths = NULL;
185 
186 	memset(&search, 0, sizeof(struct mansearch));
187 	search.outkey = "Nd";
188 	oarg = NULL;
189 
190 	if (strcmp(progname, BINM_MAN) == 0)
191 		search.argmode = ARG_NAME;
192 	else if (strcmp(progname, BINM_APROPOS) == 0)
193 		search.argmode = ARG_EXPR;
194 	else if (strcmp(progname, BINM_WHATIS) == 0)
195 		search.argmode = ARG_WORD;
196 	else if (strncmp(progname, "help", 4) == 0)
197 		search.argmode = ARG_NAME;
198 	else
199 		search.argmode = ARG_FILE;
200 
201 	/* Parser options. */
202 
203 	options = MPARSE_SO | MPARSE_UTF8 | MPARSE_LATIN1;
204 	os_e = MANDOC_OS_OTHER;
205 	os_s = NULL;
206 
207 	/* Formatter options. */
208 
209 	memset(&outst, 0, sizeof(outst));
210 	outst.tag_files = NULL;
211 	outst.outtype = OUTT_LOCALE;
212 	outst.use_pager = 1;
213 
214 	show_usage = 0;
215 	outmode = OUTMODE_DEF;
216 
217 	while ((c = getopt(argc, argv,
218 	    "aC:cfhI:iK:klM:m:O:S:s:T:VW:w")) != -1) {
219 		if (c == 'i' && search.argmode == ARG_EXPR) {
220 			optind--;
221 			break;
222 		}
223 		switch (c) {
224 		case 'a':
225 			outmode = OUTMODE_ALL;
226 			break;
227 		case 'C':
228 			conf_file = optarg;
229 			break;
230 		case 'c':
231 			outst.use_pager = 0;
232 			break;
233 		case 'f':
234 			search.argmode = ARG_WORD;
235 			break;
236 		case 'h':
237 			conf.output.synopsisonly = 1;
238 			outst.use_pager = 0;
239 			outmode = OUTMODE_ALL;
240 			break;
241 		case 'I':
242 			if (strncmp(optarg, "os=", 3) != 0) {
243 				mandoc_msg(MANDOCERR_BADARG_BAD, 0, 0,
244 				    "-I %s", optarg);
245 				return mandoc_msg_getrc();
246 			}
247 			if (os_s != NULL) {
248 				mandoc_msg(MANDOCERR_BADARG_DUPE, 0, 0,
249 				    "-I %s", optarg);
250 				return mandoc_msg_getrc();
251 			}
252 			os_s = optarg + 3;
253 			break;
254 		case 'K':
255 			options &= ~(MPARSE_UTF8 | MPARSE_LATIN1);
256 			if (strcmp(optarg, "utf-8") == 0)
257 				options |=  MPARSE_UTF8;
258 			else if (strcmp(optarg, "iso-8859-1") == 0)
259 				options |=  MPARSE_LATIN1;
260 			else if (strcmp(optarg, "us-ascii") != 0) {
261 				mandoc_msg(MANDOCERR_BADARG_BAD, 0, 0,
262 				    "-K %s", optarg);
263 				return mandoc_msg_getrc();
264 			}
265 			break;
266 		case 'k':
267 			search.argmode = ARG_EXPR;
268 			break;
269 		case 'l':
270 			search.argmode = ARG_FILE;
271 			outmode = OUTMODE_ALL;
272 			break;
273 		case 'M':
274 #ifdef __FreeBSD__
275 			defpaths = strdup(optarg);
276 			if (defpaths == NULL)
277 				err(1, "strdup");
278 #else
279 			defpaths = optarg;
280 #endif
281 			break;
282 		case 'm':
283 			auxpaths = optarg;
284 			break;
285 		case 'O':
286 			oarg = optarg;
287 			break;
288 		case 'S':
289 			search.arch = optarg;
290 			break;
291 		case 's':
292 			search.sec = optarg;
293 			break;
294 		case 'T':
295 			if (strcmp(optarg, "ascii") == 0)
296 				outst.outtype = OUTT_ASCII;
297 			else if (strcmp(optarg, "lint") == 0) {
298 				outst.outtype = OUTT_LINT;
299 				mandoc_msg_setoutfile(stdout);
300 				mandoc_msg_setmin(MANDOCERR_BASE);
301 			} else if (strcmp(optarg, "tree") == 0)
302 				outst.outtype = OUTT_TREE;
303 			else if (strcmp(optarg, "man") == 0)
304 				outst.outtype = OUTT_MAN;
305 			else if (strcmp(optarg, "html") == 0)
306 				outst.outtype = OUTT_HTML;
307 			else if (strcmp(optarg, "markdown") == 0)
308 				outst.outtype = OUTT_MARKDOWN;
309 			else if (strcmp(optarg, "utf8") == 0)
310 				outst.outtype = OUTT_UTF8;
311 			else if (strcmp(optarg, "locale") == 0)
312 				outst.outtype = OUTT_LOCALE;
313 			else if (strcmp(optarg, "ps") == 0)
314 				outst.outtype = OUTT_PS;
315 			else if (strcmp(optarg, "pdf") == 0)
316 				outst.outtype = OUTT_PDF;
317 			else {
318 				mandoc_msg(MANDOCERR_BADARG_BAD, 0, 0,
319 				    "-T %s", optarg);
320 				return mandoc_msg_getrc();
321 			}
322 			break;
323 		case 'W':
324 			if (woptions(optarg, &os_e, &outst.wstop) == -1)
325 				return mandoc_msg_getrc();
326 			break;
327 		case 'w':
328 			outmode = OUTMODE_FLN;
329 			break;
330 		default:
331 			show_usage = 1;
332 			break;
333 		}
334 	}
335 
336 	if (show_usage)
337 		usage(search.argmode);
338 
339 	/* Postprocess options. */
340 
341 	switch (outmode) {
342 	case OUTMODE_DEF:
343 		switch (search.argmode) {
344 		case ARG_FILE:
345 			outmode = OUTMODE_ALL;
346 			outst.use_pager = 0;
347 			break;
348 		case ARG_NAME:
349 			outmode = OUTMODE_ONE;
350 			break;
351 		default:
352 			outmode = OUTMODE_LST;
353 			break;
354 		}
355 		break;
356 	case OUTMODE_FLN:
357 		if (search.argmode == ARG_FILE)
358 			outmode = OUTMODE_ALL;
359 		break;
360 	case OUTMODE_ALL:
361 		break;
362 	case OUTMODE_LST:
363 	case OUTMODE_ONE:
364 		abort();
365 	}
366 
367 	if (oarg != NULL) {
368 		if (outmode == OUTMODE_LST)
369 			search.outkey = oarg;
370 		else {
371 			while (oarg != NULL) {
372 				if (manconf_output(&conf.output,
373 				    strsep(&oarg, ","), 0) == -1)
374 					return mandoc_msg_getrc();
375 			}
376 		}
377 	}
378 
379 	if (outst.outtype != OUTT_TREE || conf.output.noval == 0)
380 		options |= MPARSE_VALIDATE;
381 
382 	if (outmode == OUTMODE_FLN ||
383 	    outmode == OUTMODE_LST ||
384 	    (conf.output.outfilename == NULL &&
385 	     conf.output.tagfilename == NULL &&
386 	     isatty(STDOUT_FILENO) == 0))
387 		outst.use_pager = 0;
388 
389 	if (outst.use_pager &&
390 	    (conf.output.width == 0 || conf.output.indent == 0) &&
391 	    ioctl(STDOUT_FILENO, TIOCGWINSZ, &ws) != -1 &&
392 	    ws.ws_col > 1) {
393 		if (conf.output.width == 0 && ws.ws_col < 79)
394 			conf.output.width = ws.ws_col - 1;
395 		if (conf.output.indent == 0 && ws.ws_col < 66)
396 			conf.output.indent = 3;
397 	}
398 
399 #if HAVE_PLEDGE
400 	if (outst.use_pager == 0)
401 		c = pledge("stdio rpath", NULL);
402 	else if (conf.output.outfilename != NULL ||
403 	    conf.output.tagfilename != NULL)
404 		c = pledge("stdio rpath wpath cpath", NULL);
405 	else
406 		c = pledge("stdio rpath tmppath tty proc exec", NULL);
407 	if (c == -1) {
408 		mandoc_msg(MANDOCERR_PLEDGE, 0, 0, "%s", strerror(errno));
409 		return mandoc_msg_getrc();
410 	}
411 #endif
412 
413 	/* Parse arguments. */
414 
415 	if (argc > 0) {
416 		argc -= optind;
417 		argv += optind;
418 	}
419 
420 	/*
421 	 * Quirks for help(1) and man(1),
422 	 * in particular for a section argument without -s.
423 	 */
424 
425 	if (search.argmode == ARG_NAME) {
426 		if (*progname == 'h') {
427 			if (argc == 0) {
428 				argv = help_argv;
429 				argc = 1;
430 			}
431 		} else if (argc > 1 &&
432 		    ((uc = (unsigned char *)argv[0]) != NULL) &&
433 		    ((isdigit(uc[0]) && (uc[1] == '\0' ||
434 		      isalpha(uc[1]))) ||
435 		     (uc[0] == 'n' && uc[1] == '\0'))) {
436 			search.sec = (char *)uc;
437 			argv++;
438 			argc--;
439 		}
440 		if (search.arch == NULL)
441 			search.arch = getenv("MACHINE");
442 #ifdef MACHINE
443 		if (search.arch == NULL)
444 			search.arch = MACHINE;
445 #endif
446 		if (outmode == OUTMODE_ONE)
447 			search.firstmatch = 1;
448 	}
449 
450 	/*
451 	 * Use the first argument for -O tag in addition to
452 	 * using it as a search term for man(1) or apropos(1).
453 	 */
454 
455 	if (conf.output.tag != NULL && *conf.output.tag == '\0') {
456 		tagarg = argc > 0 && search.argmode == ARG_EXPR ?
457 		    strchr(*argv, '=') : NULL;
458 		conf.output.tag = tagarg == NULL ? *argv : tagarg + 1;
459 	}
460 
461 	if (search.argmode != ARG_FILE ||
462 	    mandoc_msg_getmin() == MANDOCERR_STYLE)
463 #ifdef __FreeBSD__
464 	{
465 		/*
466 		 * Use manpath(1) to populate defpaths if -M is not specified.
467 		 * Don't treat any failures as fatal.
468 		 */
469 		if (defpaths == NULL) {
470 			FILE *fp;
471 			size_t linecap = 0;
472 			ssize_t linelen;
473 
474 			if ((fp = popen("/usr/bin/manpath -q", "r")) != NULL) {
475 				if ((linelen = getline(&defpaths,
476 				    &linecap, fp)) > 0) {
477 					/* Strip trailing newline */
478 					defpaths[linelen - 1] = '\0';
479 				}
480 				pclose(fp);
481 			}
482 		}
483 #endif
484 	/* Read the configuration file. */
485 		manconf_parse(&conf, conf_file, defpaths, auxpaths);
486 #ifdef __FreeBSD__
487 		free(defpaths);
488 	}
489 #endif
490 
491 	/* man(1): Resolve each name individually. */
492 
493 	if (search.argmode == ARG_NAME) {
494 		if (argc < 1) {
495 			if (outmode != OUTMODE_FLN)
496 				usage(ARG_NAME);
497 			if (conf.manpath.sz == 0) {
498 				warnx("The manpath is empty.");
499 				mandoc_msg_setrc(MANDOCLEVEL_BADARG);
500 			} else {
501 				for (i = 0; i + 1 < conf.manpath.sz; i++)
502 					printf("%s:", conf.manpath.paths[i]);
503 				printf("%s\n", conf.manpath.paths[i]);
504 			}
505 			manconf_free(&conf);
506 			return (int)mandoc_msg_getrc();
507 		}
508 		for (res = NULL, ressz = 0; argc > 0; argc--, argv++) {
509 			(void)mansearch(&search, &conf.manpath,
510 			    1, argv, &resn, &resnsz);
511 			if (resnsz == 0)
512 				(void)fs_search(&search, &conf.manpath,
513 				    *argv, &resn, &resnsz);
514 			if (resnsz == 0 && strchr(*argv, '/') == NULL) {
515 				if (search.arch != NULL &&
516 				    arch_valid(search.arch, OSENUM) == 0)
517 					warnx("Unknown architecture \"%s\".",
518 					    search.arch);
519 				else if (search.sec != NULL)
520 					warnx("No entry for %s in "
521 					    "section %s of the manual.",
522 					    *argv, search.sec);
523 				else
524 					warnx("No entry for %s in "
525 					    "the manual.", *argv);
526 				mandoc_msg_setrc(MANDOCLEVEL_BADARG);
527 				continue;
528 			}
529 			if (resnsz == 0) {
530 				if (access(*argv, R_OK) == -1) {
531 					mandoc_msg_setinfilename(*argv);
532 					mandoc_msg(MANDOCERR_BADARG_BAD,
533 					    0, 0, "%s", strerror(errno));
534 					mandoc_msg_setinfilename(NULL);
535 					continue;
536 				}
537 				resnsz = 1;
538 				resn = mandoc_calloc(resnsz, sizeof(*res));
539 				resn->file = mandoc_strdup(*argv);
540 				resn->ipath = SIZE_MAX;
541 				resn->form = FORM_SRC;
542 			}
543 			if (outmode != OUTMODE_ONE || resnsz == 1) {
544 				res = mandoc_reallocarray(res,
545 				    ressz + resnsz, sizeof(*res));
546 				memcpy(res + ressz, resn,
547 				    sizeof(*resn) * resnsz);
548 				ressz += resnsz;
549 				continue;
550 			}
551 
552 			/* Search for the best section. */
553 
554 			best_prio = 40;
555 			for (ib = i = 0; i < resnsz; i++) {
556 				sec = resn[i].file;
557 				sec += strcspn(sec, "123456789");
558 				if (sec[0] == '\0')
559 					continue; /* No section at all. */
560 				prio = sec_prios[sec[0] - '1'];
561 				if (search.sec != NULL) {
562 					ssz = strlen(search.sec);
563 					if (strncmp(sec, search.sec, ssz) == 0)
564 						sec += ssz;
565 				} else
566 					sec++; /* Prefer without suffix. */
567 				if (*sec != '/')
568 					prio += 10; /* Wrong dir name. */
569 				if (search.sec != NULL) {
570 					ep = strchr(sec, '\0');
571 					if (ep - sec > 3 &&
572 					    strncmp(ep - 3, ".gz", 3) == 0)
573 						ep -= 3;
574 					if ((size_t)(ep - sec) < ssz + 3 ||
575 					    strncmp(ep - ssz, search.sec,
576 					     ssz) != 0)      /* Wrong file */
577 						prio += 20;  /* extension. */
578 				}
579 				if (prio >= best_prio)
580 					continue;
581 				best_prio = prio;
582 				ib = i;
583 			}
584 			res = mandoc_reallocarray(res, ressz + 1,
585 			    sizeof(*res));
586 			memcpy(res + ressz++, resn + ib, sizeof(*resn));
587 		}
588 
589 	/* apropos(1), whatis(1): Process the full search expression. */
590 
591 	} else if (search.argmode != ARG_FILE) {
592 		if (mansearch(&search, &conf.manpath,
593 		    argc, argv, &res, &ressz) == 0)
594 			usage(search.argmode);
595 
596 		if (ressz == 0) {
597 			warnx("nothing appropriate");
598 			mandoc_msg_setrc(MANDOCLEVEL_BADARG);
599 			goto out;
600 		}
601 
602 	/* mandoc(1): Take command line arguments as file names. */
603 
604 	} else {
605 		ressz = argc > 0 ? argc : 1;
606 		res = mandoc_calloc(ressz, sizeof(*res));
607 		for (i = 0; i < ressz; i++) {
608 			if (argc > 0)
609 				res[i].file = mandoc_strdup(argv[i]);
610 			res[i].ipath = SIZE_MAX;
611 			res[i].form = FORM_SRC;
612 		}
613 	}
614 
615 	switch (outmode) {
616 	case OUTMODE_FLN:
617 		for (i = 0; i < ressz; i++)
618 			puts(res[i].file);
619 		goto out;
620 	case OUTMODE_LST:
621 		for (i = 0; i < ressz; i++)
622 			printf("%s - %s\n", res[i].names,
623 			    res[i].output == NULL ? "" :
624 			    res[i].output);
625 		goto out;
626 	default:
627 		break;
628 	}
629 
630 	if (search.argmode == ARG_FILE && auxpaths != NULL) {
631 		if (strcmp(auxpaths, "doc") == 0)
632 			options |= MPARSE_MDOC;
633 		else if (strcmp(auxpaths, "an") == 0)
634 			options |= MPARSE_MAN;
635 	}
636 
637 	mchars_alloc();
638 	mp = mparse_alloc(options, os_e, os_s);
639 
640 	/*
641 	 * Remember the original working directory, if possible.
642 	 * This will be needed if some names on the command line
643 	 * are page names and some are relative file names.
644 	 * Do not error out if the current directory is not
645 	 * readable: Maybe it won't be needed after all.
646 	 */
647 	startdir = open(".", O_RDONLY | O_DIRECTORY);
648 	for (i = 0; i < ressz; i++) {
649 		process_onefile(mp, res + i, startdir, &outst, &conf);
650 		if (outst.wstop && mandoc_msg_getrc() != MANDOCLEVEL_OK)
651 			break;
652 	}
653 	if (startdir != -1) {
654 		(void)fchdir(startdir);
655 		close(startdir);
656 	}
657 	if (conf.output.tag != NULL && conf.output.tag_found == 0) {
658 		mandoc_msg(MANDOCERR_TAG, 0, 0, "%s", conf.output.tag);
659 		conf.output.tag = NULL;
660 	}
661 	if (outst.outdata != NULL) {
662 		switch (outst.outtype) {
663 		case OUTT_HTML:
664 			html_free(outst.outdata);
665 			break;
666 		case OUTT_UTF8:
667 		case OUTT_LOCALE:
668 		case OUTT_ASCII:
669 			ascii_free(outst.outdata);
670 			break;
671 		case OUTT_PDF:
672 		case OUTT_PS:
673 			pspdf_free(outst.outdata);
674 			break;
675 		default:
676 			break;
677 		}
678 	}
679 	mandoc_xr_free();
680 	mparse_free(mp);
681 	mchars_free();
682 
683 out:
684 	mansearch_free(res, ressz);
685 	if (search.argmode != ARG_FILE)
686 		manconf_free(&conf);
687 
688 	if (outst.tag_files != NULL) {
689 		if (term_tag_close() != -1 &&
690 		    conf.output.outfilename == NULL &&
691 		    conf.output.tagfilename == NULL)
692 			run_pager(&outst, conf.output.tag);
693 		term_tag_unlink();
694 	} else if (outst.had_output && outst.outtype != OUTT_LINT)
695 		mandoc_msg_summary();
696 
697 	return (int)mandoc_msg_getrc();
698 }
699 
700 static void
701 usage(enum argmode argmode)
702 {
703 	switch (argmode) {
704 	case ARG_FILE:
705 		fputs("usage: mandoc [-ac] [-I os=name] "
706 		    "[-K encoding] [-mdoc | -man] [-O options]\n"
707 		    "\t      [-T output] [-W level] [file ...]\n", stderr);
708 		break;
709 	case ARG_NAME:
710 		fputs("usage: man [-acfhklw] [-C file] [-M path] "
711 		    "[-m path] [-S subsection]\n"
712 		    "\t   [[-s] section] name ...\n", stderr);
713 		break;
714 	case ARG_WORD:
715 		fputs("usage: whatis [-afk] [-C file] "
716 		    "[-M path] [-m path] [-O outkey] [-S arch]\n"
717 		    "\t      [-s section] name ...\n", stderr);
718 		break;
719 	case ARG_EXPR:
720 		fputs("usage: apropos [-afk] [-C file] "
721 		    "[-M path] [-m path] [-O outkey] [-S arch]\n"
722 		    "\t       [-s section] expression ...\n", stderr);
723 		break;
724 	}
725 	exit((int)MANDOCLEVEL_BADARG);
726 }
727 
728 static void
729 glob_esc(char **dst, const char *src, const char *suffix)
730 {
731 	while (*src != '\0') {
732 		if (strchr("*?[", *src) != NULL)
733 			*(*dst)++ = '\\';
734 		*(*dst)++ = *src++;
735 	}
736 	while (*suffix != '\0')
737 		*(*dst)++ = *suffix++;
738 }
739 
740 static void
741 fs_append(char **file, size_t filesz, int copy, size_t ipath,
742     const char *sec, enum form form, struct manpage **res, size_t *ressz)
743 {
744 	struct manpage	*page;
745 
746 	*res = mandoc_reallocarray(*res, *ressz + filesz, sizeof(**res));
747 	page = *res + *ressz;
748 	*ressz += filesz;
749 	for (;;) {
750 		page->file = copy ? mandoc_strdup(*file) : *file;
751 		page->names = NULL;
752 		page->output = NULL;
753 		page->bits = NAME_FILE & NAME_MASK;
754 		page->ipath = ipath;
755 		page->sec = (*sec >= '1' && *sec <= '9') ? *sec - '1' + 1 : 10;
756 		page->form = form;
757 		if (--filesz == 0)
758 			break;
759 		file++;
760 		page++;
761 	}
762 }
763 
764 static int
765 fs_lookup(const struct manpaths *paths, size_t ipath,
766 	const char *sec, const char *arch, const char *name,
767 	struct manpage **res, size_t *ressz)
768 {
769 	struct stat	 sb;
770 	glob_t		 globinfo;
771 	char		*file, *cp, secnum[2];
772 	int		 globres;
773 	enum form	 form;
774 
775 	const char *const slman = "/man";
776 	const char *const slash = "/";
777 	const char *const sglob = ".[01-9]*";
778 	const char *const dot   = ".";
779 	const char *const aster = "*";
780 
781 	memset(&globinfo, 0, sizeof(globinfo));
782 	form = FORM_SRC;
783 
784 	mandoc_asprintf(&file, "%s/man%s/%s.%s",
785 	    paths->paths[ipath], sec, name, sec);
786 	if (stat(file, &sb) != -1)
787 		goto found;
788 	free(file);
789 
790 	mandoc_asprintf(&file, "%s/cat%s/%s.0",
791 	    paths->paths[ipath], sec, name);
792 	if (stat(file, &sb) != -1) {
793 		form = FORM_CAT;
794 		goto found;
795 	}
796 	free(file);
797 
798 	if (arch != NULL) {
799 		mandoc_asprintf(&file, "%s/man%s/%s/%s.%s",
800 		    paths->paths[ipath], sec, arch, name, sec);
801 		if (stat(file, &sb) != -1)
802 			goto found;
803 		free(file);
804 	}
805 
806 	cp = file = mandoc_malloc(strlen(paths->paths[ipath]) * 2 +
807 	    strlen(slman) + strlen(sec) * 2 + strlen(slash) +
808 	    strlen(name) * 2 + strlen(sglob) + 1);
809 	glob_esc(&cp, paths->paths[ipath], slman);
810 	glob_esc(&cp, sec, slash);
811 	glob_esc(&cp, name, sglob);
812 	*cp = '\0';
813 	globres = glob(file, 0, NULL, &globinfo);
814 	if (globres != 0 && globres != GLOB_NOMATCH)
815 		mandoc_msg(MANDOCERR_GLOB, 0, 0,
816 		    "%s: %s", file, strerror(errno));
817 	free(file);
818 	file = NULL;
819 	if (globres == 0)
820 		goto found;
821 	globfree(&globinfo);
822 
823 	if (sec[1] != '\0' && *ressz == 0) {
824 		secnum[0] = sec[0];
825 		secnum[1] = '\0';
826 		cp = file = mandoc_malloc(strlen(paths->paths[ipath]) * 2 +
827 		    strlen(slman) + strlen(secnum) * 2 + strlen(slash) +
828 		    strlen(name) * 2 + strlen(dot) +
829 		    strlen(sec) * 2 + strlen(aster) + 1);
830 		glob_esc(&cp, paths->paths[ipath], slman);
831 		glob_esc(&cp, secnum, slash);
832 		glob_esc(&cp, name, dot);
833 		glob_esc(&cp, sec, aster);
834 		*cp = '\0';
835 		globres = glob(file, 0, NULL, &globinfo);
836 		if (globres != 0 && globres != GLOB_NOMATCH)
837 			mandoc_msg(MANDOCERR_GLOB, 0, 0,
838 			    "%s: %s", file, strerror(errno));
839 		free(file);
840 		file = NULL;
841 		if (globres == 0)
842 			goto found;
843 		globfree(&globinfo);
844 	}
845 
846 	if (res != NULL || ipath + 1 != paths->sz)
847 		return -1;
848 
849 	mandoc_asprintf(&file, "%s.%s", name, sec);
850 	globres = stat(file, &sb);
851 	free(file);
852 	return globres;
853 
854 found:
855 	warnx("outdated mandoc.db lacks %s(%s) entry, run %s %s",
856 	    name, sec, BINM_MAKEWHATIS, paths->paths[ipath]);
857 	if (res == NULL)
858 		free(file);
859 	else if (file == NULL)
860 		fs_append(globinfo.gl_pathv, globinfo.gl_pathc, 1,
861 		    ipath, sec, form, res, ressz);
862 	else
863 		fs_append(&file, 1, 0, ipath, sec, form, res, ressz);
864 	globfree(&globinfo);
865 	return 0;
866 }
867 
868 static int
869 fs_search(const struct mansearch *cfg, const struct manpaths *paths,
870 	const char *name, struct manpage **res, size_t *ressz)
871 {
872 	const char *const sections[] =
873 	    {"1", "8", "6", "2", "3", "5", "7", "4", "9", "3p"};
874 	const size_t nsec = sizeof(sections)/sizeof(sections[0]);
875 
876 	size_t		 ipath, isec;
877 
878 	assert(cfg->argmode == ARG_NAME);
879 	if (res != NULL)
880 		*res = NULL;
881 	*ressz = 0;
882 	for (ipath = 0; ipath < paths->sz; ipath++) {
883 		if (cfg->sec != NULL) {
884 			if (fs_lookup(paths, ipath, cfg->sec, cfg->arch,
885 			    name, res, ressz) != -1 && cfg->firstmatch)
886 				return 0;
887 		} else {
888 			for (isec = 0; isec < nsec; isec++)
889 				if (fs_lookup(paths, ipath, sections[isec],
890 				    cfg->arch, name, res, ressz) != -1 &&
891 				    cfg->firstmatch)
892 					return 0;
893 		}
894 	}
895 	return -1;
896 }
897 
898 static void
899 process_onefile(struct mparse *mp, struct manpage *resp, int startdir,
900     struct outstate *outst, struct manconf *conf)
901 {
902 	int	 fd;
903 
904 	/*
905 	 * Changing directories is not needed in ARG_FILE mode.
906 	 * Do it on a best-effort basis.  Even in case of
907 	 * failure, some functionality may still work.
908 	 */
909 	if (resp->ipath != SIZE_MAX)
910 		(void)chdir(conf->manpath.paths[resp->ipath]);
911 	else if (startdir != -1)
912 		(void)fchdir(startdir);
913 
914 	mandoc_msg_setinfilename(resp->file);
915 	if (resp->file != NULL) {
916 		if ((fd = mparse_open(mp, resp->file)) == -1) {
917 			mandoc_msg(resp->ipath == SIZE_MAX ?
918 			    MANDOCERR_BADARG_BAD : MANDOCERR_OPEN,
919 			    0, 0, "%s", strerror(errno));
920 			mandoc_msg_setinfilename(NULL);
921 			return;
922 		}
923 	} else
924 		fd = STDIN_FILENO;
925 
926 	if (outst->use_pager) {
927 		outst->use_pager = 0;
928 		outst->tag_files = term_tag_init(conf->output.outfilename,
929 		    outst->outtype == OUTT_HTML ? ".html" : "",
930 		    conf->output.tagfilename);
931 #if HAVE_PLEDGE
932 		if ((conf->output.outfilename != NULL ||
933 		     conf->output.tagfilename != NULL) &&
934 		    pledge("stdio rpath cpath", NULL) == -1) {
935 			mandoc_msg(MANDOCERR_PLEDGE, 0, 0,
936 			    "%s", strerror(errno));
937 			exit(mandoc_msg_getrc());
938 		}
939 #endif
940 	}
941 	if (outst->had_output && outst->outtype <= OUTT_UTF8) {
942 		if (outst->outdata == NULL)
943 			outdata_alloc(outst, &conf->output);
944 		terminal_sepline(outst->outdata);
945 	}
946 
947 	if (resp->form == FORM_SRC)
948 		parse(mp, fd, resp->file, outst, conf);
949 	else {
950 		passthrough(fd, conf->output.synopsisonly);
951 		outst->had_output = 1;
952 	}
953 
954 	if (ferror(stdout)) {
955 		if (outst->tag_files != NULL) {
956 			mandoc_msg(MANDOCERR_WRITE, 0, 0, "%s: %s",
957 			    outst->tag_files->ofn, strerror(errno));
958 			term_tag_unlink();
959 			outst->tag_files = NULL;
960 		} else
961 			mandoc_msg(MANDOCERR_WRITE, 0, 0, "%s",
962 			    strerror(errno));
963 	}
964 	mandoc_msg_setinfilename(NULL);
965 }
966 
967 static void
968 parse(struct mparse *mp, int fd, const char *file,
969     struct outstate *outst, struct manconf *conf)
970 {
971 	static struct manpaths	 basepaths;
972 	static int		 previous;
973 	struct roff_meta	*meta;
974 
975 	assert(fd >= 0);
976 	if (file == NULL)
977 		file = "<stdin>";
978 
979 	if (previous)
980 		mparse_reset(mp);
981 	else
982 		previous = 1;
983 
984 	mparse_readfd(mp, fd, file);
985 	if (fd != STDIN_FILENO)
986 		close(fd);
987 
988 	/*
989 	 * With -Wstop and warnings or errors of at least the requested
990 	 * level, do not produce output.
991 	 */
992 
993 	if (outst->wstop && mandoc_msg_getrc() != MANDOCLEVEL_OK)
994 		return;
995 
996 	if (outst->outdata == NULL)
997 		outdata_alloc(outst, &conf->output);
998 	else if (outst->outtype == OUTT_HTML)
999 		html_reset(outst->outdata);
1000 
1001 	mandoc_xr_reset();
1002 	meta = mparse_result(mp);
1003 
1004 	/* Execute the out device, if it exists. */
1005 
1006 	outst->had_output = 1;
1007 	if (meta->macroset == MACROSET_MDOC) {
1008 		switch (outst->outtype) {
1009 		case OUTT_HTML:
1010 			html_mdoc(outst->outdata, meta);
1011 			break;
1012 		case OUTT_TREE:
1013 			tree_mdoc(outst->outdata, meta);
1014 			break;
1015 		case OUTT_MAN:
1016 			man_mdoc(outst->outdata, meta);
1017 			break;
1018 		case OUTT_PDF:
1019 		case OUTT_ASCII:
1020 		case OUTT_UTF8:
1021 		case OUTT_LOCALE:
1022 		case OUTT_PS:
1023 			terminal_mdoc(outst->outdata, meta);
1024 			break;
1025 		case OUTT_MARKDOWN:
1026 			markdown_mdoc(outst->outdata, meta);
1027 			break;
1028 		default:
1029 			break;
1030 		}
1031 	}
1032 	if (meta->macroset == MACROSET_MAN) {
1033 		switch (outst->outtype) {
1034 		case OUTT_HTML:
1035 			html_man(outst->outdata, meta);
1036 			break;
1037 		case OUTT_TREE:
1038 			tree_man(outst->outdata, meta);
1039 			break;
1040 		case OUTT_MAN:
1041 			mparse_copy(mp);
1042 			break;
1043 		case OUTT_PDF:
1044 		case OUTT_ASCII:
1045 		case OUTT_UTF8:
1046 		case OUTT_LOCALE:
1047 		case OUTT_PS:
1048 			terminal_man(outst->outdata, meta);
1049 			break;
1050 		case OUTT_MARKDOWN:
1051 			mandoc_msg(MANDOCERR_MAN_TMARKDOWN, 0, 0, NULL);
1052 			break;
1053 		default:
1054 			break;
1055 		}
1056 	}
1057 	if (conf->output.tag != NULL && conf->output.tag_found == 0 &&
1058 	    tag_exists(conf->output.tag))
1059 		conf->output.tag_found = 1;
1060 
1061 	if (mandoc_msg_getmin() < MANDOCERR_STYLE) {
1062 		if (basepaths.sz == 0)
1063 			manpath_base(&basepaths);
1064 		check_xr(&basepaths);
1065 	} else if (mandoc_msg_getmin() < MANDOCERR_WARNING)
1066 		check_xr(&conf->manpath);
1067 }
1068 
1069 static void
1070 check_xr(struct manpaths *paths)
1071 {
1072 	struct mansearch	 search;
1073 	struct mandoc_xr	*xr;
1074 	size_t			 sz;
1075 
1076 	for (xr = mandoc_xr_get(); xr != NULL; xr = xr->next) {
1077 		if (xr->line == -1)
1078 			continue;
1079 		search.arch = NULL;
1080 		search.sec = xr->sec;
1081 		search.outkey = NULL;
1082 		search.argmode = ARG_NAME;
1083 		search.firstmatch = 1;
1084 		if (mansearch(&search, paths, 1, &xr->name, NULL, &sz))
1085 			continue;
1086 		if (fs_search(&search, paths, xr->name, NULL, &sz) != -1)
1087 			continue;
1088 		if (xr->count == 1)
1089 			mandoc_msg(MANDOCERR_XR_BAD, xr->line,
1090 			    xr->pos + 1, "Xr %s %s", xr->name, xr->sec);
1091 		else
1092 			mandoc_msg(MANDOCERR_XR_BAD, xr->line,
1093 			    xr->pos + 1, "Xr %s %s (%d times)",
1094 			    xr->name, xr->sec, xr->count);
1095 	}
1096 }
1097 
1098 static void
1099 outdata_alloc(struct outstate *outst, struct manoutput *outconf)
1100 {
1101 	switch (outst->outtype) {
1102 	case OUTT_HTML:
1103 		outst->outdata = html_alloc(outconf);
1104 		break;
1105 	case OUTT_UTF8:
1106 		outst->outdata = utf8_alloc(outconf);
1107 		break;
1108 	case OUTT_LOCALE:
1109 		outst->outdata = locale_alloc(outconf);
1110 		break;
1111 	case OUTT_ASCII:
1112 		outst->outdata = ascii_alloc(outconf);
1113 		break;
1114 	case OUTT_PDF:
1115 		outst->outdata = pdf_alloc(outconf);
1116 		break;
1117 	case OUTT_PS:
1118 		outst->outdata = ps_alloc(outconf);
1119 		break;
1120 	default:
1121 		break;
1122 	}
1123 }
1124 
1125 static void
1126 passthrough(int fd, int synopsis_only)
1127 {
1128 	const char	 synb[] = "S\bSY\bYN\bNO\bOP\bPS\bSI\bIS\bS";
1129 	const char	 synr[] = "SYNOPSIS";
1130 
1131 	FILE		*stream;
1132 	char		*line, *cp;
1133 	size_t		 linesz;
1134 	ssize_t		 len, written;
1135 	int		 lno, print;
1136 
1137 	stream = NULL;
1138 	line = NULL;
1139 	linesz = 0;
1140 
1141 	if (fflush(stdout) == EOF) {
1142 		mandoc_msg(MANDOCERR_FFLUSH, 0, 0, "%s", strerror(errno));
1143 		goto done;
1144 	}
1145 	if ((stream = fdopen(fd, "r")) == NULL) {
1146 		close(fd);
1147 		mandoc_msg(MANDOCERR_FDOPEN, 0, 0, "%s", strerror(errno));
1148 		goto done;
1149 	}
1150 
1151 	lno = print = 0;
1152 	while ((len = getline(&line, &linesz, stream)) != -1) {
1153 		lno++;
1154 		cp = line;
1155 		if (synopsis_only) {
1156 			if (print) {
1157 				if ( ! isspace((unsigned char)*cp))
1158 					goto done;
1159 				while (isspace((unsigned char)*cp)) {
1160 					cp++;
1161 					len--;
1162 				}
1163 			} else {
1164 				if (strcmp(cp, synb) == 0 ||
1165 				    strcmp(cp, synr) == 0)
1166 					print = 1;
1167 				continue;
1168 			}
1169 		}
1170 		for (; len > 0; len -= written) {
1171 			if ((written = write(STDOUT_FILENO, cp, len)) == -1) {
1172 				mandoc_msg(MANDOCERR_WRITE, 0, 0,
1173 				    "%s", strerror(errno));
1174 				goto done;
1175 			}
1176 		}
1177 	}
1178 	if (ferror(stream))
1179 		mandoc_msg(MANDOCERR_GETLINE, lno, 0, "%s", strerror(errno));
1180 
1181 done:
1182 	free(line);
1183 	if (stream != NULL)
1184 		fclose(stream);
1185 }
1186 
1187 static int
1188 woptions(char *arg, enum mandoc_os *os_e, int *wstop)
1189 {
1190 	char		*v, *o;
1191 	const char	*toks[11];
1192 
1193 	toks[0] = "stop";
1194 	toks[1] = "all";
1195 	toks[2] = "base";
1196 	toks[3] = "style";
1197 	toks[4] = "warning";
1198 	toks[5] = "error";
1199 	toks[6] = "unsupp";
1200 	toks[7] = "fatal";
1201 	toks[8] = "openbsd";
1202 	toks[9] = "netbsd";
1203 	toks[10] = NULL;
1204 
1205 	while (*arg) {
1206 		o = arg;
1207 		switch (getsubopt(&arg, (char * const *)toks, &v)) {
1208 		case 0:
1209 			*wstop = 1;
1210 			break;
1211 		case 1:
1212 		case 2:
1213 			mandoc_msg_setmin(MANDOCERR_BASE);
1214 			break;
1215 		case 3:
1216 			mandoc_msg_setmin(MANDOCERR_STYLE);
1217 			break;
1218 		case 4:
1219 			mandoc_msg_setmin(MANDOCERR_WARNING);
1220 			break;
1221 		case 5:
1222 			mandoc_msg_setmin(MANDOCERR_ERROR);
1223 			break;
1224 		case 6:
1225 			mandoc_msg_setmin(MANDOCERR_UNSUPP);
1226 			break;
1227 		case 7:
1228 			mandoc_msg_setmin(MANDOCERR_BADARG);
1229 			break;
1230 		case 8:
1231 			mandoc_msg_setmin(MANDOCERR_BASE);
1232 			*os_e = MANDOC_OS_OPENBSD;
1233 			break;
1234 		case 9:
1235 			mandoc_msg_setmin(MANDOCERR_BASE);
1236 			*os_e = MANDOC_OS_NETBSD;
1237 			break;
1238 		default:
1239 			mandoc_msg(MANDOCERR_BADARG_BAD, 0, 0, "-W %s", o);
1240 			return -1;
1241 		}
1242 	}
1243 	return 0;
1244 }
1245 
1246 /*
1247  * Wait until moved to the foreground,
1248  * then fork the pager and wait for the user to close it.
1249  */
1250 static void
1251 run_pager(struct outstate *outst, char *tag_target)
1252 {
1253 	int	 signum, status;
1254 	pid_t	 man_pgid, tc_pgid;
1255 	pid_t	 pager_pid, wait_pid;
1256 
1257 	man_pgid = getpgid(0);
1258 	outst->tag_files->tcpgid =
1259 	    man_pgid == getpid() ? getpgid(getppid()) : man_pgid;
1260 	pager_pid = 0;
1261 	signum = SIGSTOP;
1262 
1263 	for (;;) {
1264 		/* Stop here until moved to the foreground. */
1265 
1266 		tc_pgid = tcgetpgrp(STDOUT_FILENO);
1267 		if (tc_pgid != man_pgid) {
1268 			if (tc_pgid == pager_pid) {
1269 				(void)tcsetpgrp(STDOUT_FILENO, man_pgid);
1270 				if (signum == SIGTTIN)
1271 					continue;
1272 			} else
1273 				outst->tag_files->tcpgid = tc_pgid;
1274 			kill(0, signum);
1275 			continue;
1276 		}
1277 
1278 		/* Once in the foreground, activate the pager. */
1279 
1280 		if (pager_pid) {
1281 			(void)tcsetpgrp(STDOUT_FILENO, pager_pid);
1282 			kill(pager_pid, SIGCONT);
1283 		} else
1284 			pager_pid = spawn_pager(outst, tag_target);
1285 
1286 		/* Wait for the pager to stop or exit. */
1287 
1288 		while ((wait_pid = waitpid(pager_pid, &status,
1289 		    WUNTRACED)) == -1 && errno == EINTR)
1290 			continue;
1291 
1292 		if (wait_pid == -1) {
1293 			mandoc_msg(MANDOCERR_WAIT, 0, 0,
1294 			    "%s", strerror(errno));
1295 			break;
1296 		}
1297 		if (!WIFSTOPPED(status))
1298 			break;
1299 
1300 		signum = WSTOPSIG(status);
1301 	}
1302 }
1303 
1304 static pid_t
1305 spawn_pager(struct outstate *outst, char *tag_target)
1306 {
1307 	const struct timespec timeout = { 0, 100000000 };  /* 0.1s */
1308 #define MAX_PAGER_ARGS 16
1309 	char		*argv[MAX_PAGER_ARGS];
1310 	const char	*pager;
1311 	char		*cp;
1312 #if HAVE_LESS_T
1313 	size_t		 cmdlen;
1314 #endif
1315 	int		 argc, use_ofn;
1316 	pid_t		 pager_pid;
1317 
1318 	assert(outst->tag_files->ofd == -1);
1319 	assert(outst->tag_files->tfs == NULL);
1320 
1321 	pager = getenv("MANPAGER");
1322 	if (pager == NULL || *pager == '\0')
1323 		pager = getenv("PAGER");
1324 	if (pager == NULL || *pager == '\0')
1325 		pager = BINM_PAGER;
1326 	cp = mandoc_strdup(pager);
1327 
1328 	/*
1329 	 * Parse the pager command into words.
1330 	 * Intentionally do not do anything fancy here.
1331 	 */
1332 
1333 	argc = 0;
1334 	while (argc + 5 < MAX_PAGER_ARGS) {
1335 		argv[argc++] = cp;
1336 		cp = strchr(cp, ' ');
1337 		if (cp == NULL)
1338 			break;
1339 		*cp++ = '\0';
1340 		while (*cp == ' ')
1341 			cp++;
1342 		if (*cp == '\0')
1343 			break;
1344 	}
1345 
1346 	/* For less(1), use the tag file. */
1347 
1348 	use_ofn = 1;
1349 #if HAVE_LESS_T
1350 	if (*outst->tag_files->tfn != '\0' &&
1351 	    (cmdlen = strlen(argv[0])) >= 4) {
1352 		cp = argv[0] + cmdlen - 4;
1353 		if (strcmp(cp, "less") == 0) {
1354 			argv[argc++] = mandoc_strdup("-T");
1355 			argv[argc++] = outst->tag_files->tfn;
1356 			if (tag_target != NULL) {
1357 				argv[argc++] = mandoc_strdup("-t");
1358 				argv[argc++] = tag_target;
1359 				use_ofn = 0;
1360 			}
1361 		}
1362 	}
1363 #endif
1364 	if (use_ofn) {
1365 		if (outst->outtype == OUTT_HTML && tag_target != NULL)
1366 			mandoc_asprintf(&argv[argc], "file://%s#%s",
1367 			    outst->tag_files->ofn, tag_target);
1368 		else
1369 			argv[argc] = outst->tag_files->ofn;
1370 		argc++;
1371 	}
1372 	argv[argc] = NULL;
1373 
1374 	switch (pager_pid = fork()) {
1375 	case -1:
1376 		mandoc_msg(MANDOCERR_FORK, 0, 0, "%s", strerror(errno));
1377 		exit(mandoc_msg_getrc());
1378 	case 0:
1379 		break;
1380 	default:
1381 		(void)setpgid(pager_pid, 0);
1382 		(void)tcsetpgrp(STDOUT_FILENO, pager_pid);
1383 #if HAVE_PLEDGE
1384 		if (pledge("stdio rpath tmppath tty proc", NULL) == -1) {
1385 			mandoc_msg(MANDOCERR_PLEDGE, 0, 0,
1386 			    "%s", strerror(errno));
1387 			exit(mandoc_msg_getrc());
1388 		}
1389 #endif
1390 		outst->tag_files->pager_pid = pager_pid;
1391 		return pager_pid;
1392 	}
1393 
1394 	/*
1395 	 * The child process becomes the pager.
1396 	 * Do not start it before controlling the terminal.
1397 	 */
1398 
1399 	while (tcgetpgrp(STDOUT_FILENO) != getpid())
1400 		nanosleep(&timeout, NULL);
1401 
1402 	execvp(argv[0], argv);
1403 	mandoc_msg(MANDOCERR_EXEC, 0, 0, "%s: %s", argv[0], strerror(errno));
1404 	_exit(mandoc_msg_getrc());
1405 }
1406