xref: /illumos-gate/usr/src/cmd/mandoc/main.c (revision 4d131170)
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
main(int argc,char * argv[])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 			defpaths = optarg;
275 			break;
276 		case 'm':
277 			auxpaths = optarg;
278 			break;
279 		case 'O':
280 			oarg = optarg;
281 			break;
282 		case 'S':
283 			search.arch = optarg;
284 			break;
285 		case 's':
286 			search.sec = optarg;
287 			break;
288 		case 'T':
289 			if (strcmp(optarg, "ascii") == 0)
290 				outst.outtype = OUTT_ASCII;
291 			else if (strcmp(optarg, "lint") == 0) {
292 				outst.outtype = OUTT_LINT;
293 				mandoc_msg_setoutfile(stdout);
294 				mandoc_msg_setmin(MANDOCERR_BASE);
295 			} else if (strcmp(optarg, "tree") == 0)
296 				outst.outtype = OUTT_TREE;
297 			else if (strcmp(optarg, "man") == 0)
298 				outst.outtype = OUTT_MAN;
299 			else if (strcmp(optarg, "html") == 0)
300 				outst.outtype = OUTT_HTML;
301 			else if (strcmp(optarg, "markdown") == 0)
302 				outst.outtype = OUTT_MARKDOWN;
303 			else if (strcmp(optarg, "utf8") == 0)
304 				outst.outtype = OUTT_UTF8;
305 			else if (strcmp(optarg, "locale") == 0)
306 				outst.outtype = OUTT_LOCALE;
307 			else if (strcmp(optarg, "ps") == 0)
308 				outst.outtype = OUTT_PS;
309 			else if (strcmp(optarg, "pdf") == 0)
310 				outst.outtype = OUTT_PDF;
311 			else {
312 				mandoc_msg(MANDOCERR_BADARG_BAD, 0, 0,
313 				    "-T %s", optarg);
314 				return mandoc_msg_getrc();
315 			}
316 			break;
317 		case 'W':
318 			if (woptions(optarg, &os_e, &outst.wstop) == -1)
319 				return mandoc_msg_getrc();
320 			break;
321 		case 'w':
322 			outmode = OUTMODE_FLN;
323 			break;
324 		default:
325 			show_usage = 1;
326 			break;
327 		}
328 	}
329 
330 	if (show_usage)
331 		usage(search.argmode);
332 
333 	/* Postprocess options. */
334 
335 	switch (outmode) {
336 	case OUTMODE_DEF:
337 		switch (search.argmode) {
338 		case ARG_FILE:
339 			outmode = OUTMODE_ALL;
340 			outst.use_pager = 0;
341 			break;
342 		case ARG_NAME:
343 			outmode = OUTMODE_ONE;
344 			break;
345 		default:
346 			outmode = OUTMODE_LST;
347 			break;
348 		}
349 		break;
350 	case OUTMODE_FLN:
351 		if (search.argmode == ARG_FILE)
352 			outmode = OUTMODE_ALL;
353 		break;
354 	case OUTMODE_ALL:
355 		break;
356 	case OUTMODE_LST:
357 	case OUTMODE_ONE:
358 		abort();
359 	}
360 
361 	if (oarg != NULL) {
362 		if (outmode == OUTMODE_LST)
363 			search.outkey = oarg;
364 		else {
365 			while (oarg != NULL) {
366 				if (manconf_output(&conf.output,
367 				    strsep(&oarg, ","), 0) == -1)
368 					return mandoc_msg_getrc();
369 			}
370 		}
371 	}
372 
373 	if (outst.outtype != OUTT_TREE || conf.output.noval == 0)
374 		options |= MPARSE_VALIDATE;
375 
376 	if (outmode == OUTMODE_FLN ||
377 	    outmode == OUTMODE_LST ||
378 	    (conf.output.outfilename == NULL &&
379 	     conf.output.tagfilename == NULL &&
380 	     isatty(STDOUT_FILENO) == 0))
381 		outst.use_pager = 0;
382 
383 	if (outst.use_pager &&
384 	    (conf.output.width == 0 || conf.output.indent == 0) &&
385 	    ioctl(STDOUT_FILENO, TIOCGWINSZ, &ws) != -1 &&
386 	    ws.ws_col > 1) {
387 		if (conf.output.width == 0 && ws.ws_col < 79)
388 			conf.output.width = ws.ws_col - 1;
389 		if (conf.output.indent == 0 && ws.ws_col < 66)
390 			conf.output.indent = 3;
391 	}
392 
393 #if HAVE_PLEDGE
394 	if (outst.use_pager == 0)
395 		c = pledge("stdio rpath", NULL);
396 	else if (conf.output.outfilename != NULL ||
397 	    conf.output.tagfilename != NULL)
398 		c = pledge("stdio rpath wpath cpath", NULL);
399 	else
400 		c = pledge("stdio rpath tmppath tty proc exec", NULL);
401 	if (c == -1) {
402 		mandoc_msg(MANDOCERR_PLEDGE, 0, 0, "%s", strerror(errno));
403 		return mandoc_msg_getrc();
404 	}
405 #endif
406 
407 	/* Parse arguments. */
408 
409 	if (argc > 0) {
410 		argc -= optind;
411 		argv += optind;
412 	}
413 
414 	/*
415 	 * Quirks for help(1) and man(1),
416 	 * in particular for a section argument without -s.
417 	 */
418 
419 	if (search.argmode == ARG_NAME) {
420 		if (*progname == 'h') {
421 			if (argc == 0) {
422 				argv = help_argv;
423 				argc = 1;
424 			}
425 		} else if (argc > 1 &&
426 		    ((uc = (unsigned char *)argv[0]) != NULL) &&
427 		    ((isdigit(uc[0]) && (uc[1] == '\0' ||
428 		      isalpha(uc[1]))) ||
429 		     (uc[0] == 'n' && uc[1] == '\0'))) {
430 			search.sec = (char *)uc;
431 			argv++;
432 			argc--;
433 		}
434 		if (search.arch == NULL)
435 			search.arch = getenv("MACHINE");
436 #ifdef MACHINE
437 		if (search.arch == NULL)
438 			search.arch = MACHINE;
439 #endif
440 		if (outmode == OUTMODE_ONE)
441 			search.firstmatch = 1;
442 	}
443 
444 	/*
445 	 * Use the first argument for -O tag in addition to
446 	 * using it as a search term for man(1) or apropos(1).
447 	 */
448 
449 	if (conf.output.tag != NULL && *conf.output.tag == '\0') {
450 		tagarg = argc > 0 && search.argmode == ARG_EXPR ?
451 		    strchr(*argv, '=') : NULL;
452 		conf.output.tag = tagarg == NULL ? *argv : tagarg + 1;
453 	}
454 
455 	/* Read the configuration file. */
456 
457 	if (search.argmode != ARG_FILE ||
458 	    mandoc_msg_getmin() == MANDOCERR_STYLE)
459 		manconf_parse(&conf, conf_file, defpaths, auxpaths);
460 
461 	/* man(1): Resolve each name individually. */
462 
463 	if (search.argmode == ARG_NAME) {
464 		if (argc < 1) {
465 			if (outmode != OUTMODE_FLN)
466 				usage(ARG_NAME);
467 			if (conf.manpath.sz == 0) {
468 				warnx("The manpath is empty.");
469 				mandoc_msg_setrc(MANDOCLEVEL_BADARG);
470 			} else {
471 				for (i = 0; i + 1 < conf.manpath.sz; i++)
472 					printf("%s:", conf.manpath.paths[i]);
473 				printf("%s\n", conf.manpath.paths[i]);
474 			}
475 			manconf_free(&conf);
476 			return (int)mandoc_msg_getrc();
477 		}
478 		for (res = NULL, ressz = 0; argc > 0; argc--, argv++) {
479 			(void)mansearch(&search, &conf.manpath,
480 			    1, argv, &resn, &resnsz);
481 			if (resnsz == 0)
482 				(void)fs_search(&search, &conf.manpath,
483 				    *argv, &resn, &resnsz);
484 			if (resnsz == 0 && strchr(*argv, '/') == NULL) {
485 				if (search.arch != NULL &&
486 				    arch_valid(search.arch, OSENUM) == 0)
487 					warnx("Unknown architecture \"%s\".",
488 					    search.arch);
489 				else if (search.sec != NULL)
490 					warnx("No entry for %s in "
491 					    "section %s of the manual.",
492 					    *argv, search.sec);
493 				else
494 					warnx("No entry for %s in "
495 					    "the manual.", *argv);
496 				mandoc_msg_setrc(MANDOCLEVEL_BADARG);
497 				continue;
498 			}
499 			if (resnsz == 0) {
500 				if (access(*argv, R_OK) == -1) {
501 					mandoc_msg_setinfilename(*argv);
502 					mandoc_msg(MANDOCERR_BADARG_BAD,
503 					    0, 0, "%s", strerror(errno));
504 					mandoc_msg_setinfilename(NULL);
505 					continue;
506 				}
507 				resnsz = 1;
508 				resn = mandoc_calloc(resnsz, sizeof(*res));
509 				resn->file = mandoc_strdup(*argv);
510 				resn->ipath = SIZE_MAX;
511 				resn->form = FORM_SRC;
512 			}
513 			if (outmode != OUTMODE_ONE || resnsz == 1) {
514 				res = mandoc_reallocarray(res,
515 				    ressz + resnsz, sizeof(*res));
516 				memcpy(res + ressz, resn,
517 				    sizeof(*resn) * resnsz);
518 				ressz += resnsz;
519 				continue;
520 			}
521 
522 			/* Search for the best section. */
523 
524 			best_prio = 40;
525 			for (ib = i = 0; i < resnsz; i++) {
526 				sec = resn[i].file;
527 				sec += strcspn(sec, "123456789");
528 				if (sec[0] == '\0')
529 					continue; /* No section at all. */
530 				prio = sec_prios[sec[0] - '1'];
531 				if (search.sec != NULL) {
532 					ssz = strlen(search.sec);
533 					if (strncmp(sec, search.sec, ssz) == 0)
534 						sec += ssz;
535 				} else
536 					sec++; /* Prefer without suffix. */
537 				if (*sec != '/')
538 					prio += 10; /* Wrong dir name. */
539 				if (search.sec != NULL) {
540 					ep = strchr(sec, '\0');
541 					if (ep - sec > 3 &&
542 					    strncmp(ep - 3, ".gz", 3) == 0)
543 						ep -= 3;
544 					if ((size_t)(ep - sec) < ssz + 3 ||
545 					    strncmp(ep - ssz, search.sec,
546 					     ssz) != 0)      /* Wrong file */
547 						prio += 20;  /* extension. */
548 				}
549 				if (prio >= best_prio)
550 					continue;
551 				best_prio = prio;
552 				ib = i;
553 			}
554 			res = mandoc_reallocarray(res, ressz + 1,
555 			    sizeof(*res));
556 			memcpy(res + ressz++, resn + ib, sizeof(*resn));
557 		}
558 
559 	/* apropos(1), whatis(1): Process the full search expression. */
560 
561 	} else if (search.argmode != ARG_FILE) {
562 		if (mansearch(&search, &conf.manpath,
563 		    argc, argv, &res, &ressz) == 0)
564 			usage(search.argmode);
565 
566 		if (ressz == 0) {
567 			warnx("nothing appropriate");
568 			mandoc_msg_setrc(MANDOCLEVEL_BADARG);
569 			goto out;
570 		}
571 
572 	/* mandoc(1): Take command line arguments as file names. */
573 
574 	} else {
575 		ressz = argc > 0 ? argc : 1;
576 		res = mandoc_calloc(ressz, sizeof(*res));
577 		for (i = 0; i < ressz; i++) {
578 			if (argc > 0)
579 				res[i].file = mandoc_strdup(argv[i]);
580 			res[i].ipath = SIZE_MAX;
581 			res[i].form = FORM_SRC;
582 		}
583 	}
584 
585 	switch (outmode) {
586 	case OUTMODE_FLN:
587 		for (i = 0; i < ressz; i++)
588 			puts(res[i].file);
589 		goto out;
590 	case OUTMODE_LST:
591 		for (i = 0; i < ressz; i++)
592 			printf("%s - %s\n", res[i].names,
593 			    res[i].output == NULL ? "" :
594 			    res[i].output);
595 		goto out;
596 	default:
597 		break;
598 	}
599 
600 	if (search.argmode == ARG_FILE && auxpaths != NULL) {
601 		if (strcmp(auxpaths, "doc") == 0)
602 			options |= MPARSE_MDOC;
603 		else if (strcmp(auxpaths, "an") == 0)
604 			options |= MPARSE_MAN;
605 	}
606 
607 	mchars_alloc();
608 	mp = mparse_alloc(options, os_e, os_s);
609 
610 	/*
611 	 * Remember the original working directory, if possible.
612 	 * This will be needed if some names on the command line
613 	 * are page names and some are relative file names.
614 	 * Do not error out if the current directory is not
615 	 * readable: Maybe it won't be needed after all.
616 	 */
617 	startdir = open(".", O_RDONLY | O_DIRECTORY);
618 	for (i = 0; i < ressz; i++) {
619 		process_onefile(mp, res + i, startdir, &outst, &conf);
620 		if (outst.wstop && mandoc_msg_getrc() != MANDOCLEVEL_OK)
621 			break;
622 	}
623 	if (startdir != -1) {
624 		(void)fchdir(startdir);
625 		close(startdir);
626 	}
627 	if (conf.output.tag != NULL && conf.output.tag_found == 0) {
628 		mandoc_msg(MANDOCERR_TAG, 0, 0, "%s", conf.output.tag);
629 		conf.output.tag = NULL;
630 	}
631 	if (outst.outdata != NULL) {
632 		switch (outst.outtype) {
633 		case OUTT_HTML:
634 			html_free(outst.outdata);
635 			break;
636 		case OUTT_UTF8:
637 		case OUTT_LOCALE:
638 		case OUTT_ASCII:
639 			ascii_free(outst.outdata);
640 			break;
641 		case OUTT_PDF:
642 		case OUTT_PS:
643 			pspdf_free(outst.outdata);
644 			break;
645 		default:
646 			break;
647 		}
648 	}
649 	mandoc_xr_free();
650 	mparse_free(mp);
651 	mchars_free();
652 
653 out:
654 	mansearch_free(res, ressz);
655 	if (search.argmode != ARG_FILE)
656 		manconf_free(&conf);
657 
658 	if (outst.tag_files != NULL) {
659 		if (term_tag_close() != -1 &&
660 		    conf.output.outfilename == NULL &&
661 		    conf.output.tagfilename == NULL)
662 			run_pager(&outst, conf.output.tag);
663 		term_tag_unlink();
664 	} else if (outst.had_output && outst.outtype != OUTT_LINT)
665 		mandoc_msg_summary();
666 
667 	return (int)mandoc_msg_getrc();
668 }
669 
670 static void
usage(enum argmode argmode)671 usage(enum argmode argmode)
672 {
673 	switch (argmode) {
674 	case ARG_FILE:
675 		fputs("usage: mandoc [-ac] [-I os=name] "
676 		    "[-K encoding] [-mdoc | -man] [-O options]\n"
677 		    "\t      [-T output] [-W level] [file ...]\n", stderr);
678 		break;
679 	case ARG_NAME:
680 		fputs("usage: man [-acfhklw] [-C file] [-M path] "
681 		    "[-m path] [-S subsection]\n"
682 		    "\t   [[-s] section] name ...\n", stderr);
683 		break;
684 	case ARG_WORD:
685 		fputs("usage: whatis [-afk] [-C file] "
686 		    "[-M path] [-m path] [-O outkey] [-S arch]\n"
687 		    "\t      [-s section] name ...\n", stderr);
688 		break;
689 	case ARG_EXPR:
690 		fputs("usage: apropos [-afk] [-C file] "
691 		    "[-M path] [-m path] [-O outkey] [-S arch]\n"
692 		    "\t       [-s section] expression ...\n", stderr);
693 		break;
694 	}
695 	exit((int)MANDOCLEVEL_BADARG);
696 }
697 
698 static void
glob_esc(char ** dst,const char * src,const char * suffix)699 glob_esc(char **dst, const char *src, const char *suffix)
700 {
701 	while (*src != '\0') {
702 		if (strchr("*?[", *src) != NULL)
703 			*(*dst)++ = '\\';
704 		*(*dst)++ = *src++;
705 	}
706 	while (*suffix != '\0')
707 		*(*dst)++ = *suffix++;
708 }
709 
710 static void
fs_append(char ** file,size_t filesz,int copy,size_t ipath,const char * sec,enum form form,struct manpage ** res,size_t * ressz)711 fs_append(char **file, size_t filesz, int copy, size_t ipath,
712     const char *sec, enum form form, struct manpage **res, size_t *ressz)
713 {
714 	struct manpage	*page;
715 
716 	*res = mandoc_reallocarray(*res, *ressz + filesz, sizeof(**res));
717 	page = *res + *ressz;
718 	*ressz += filesz;
719 	for (;;) {
720 		page->file = copy ? mandoc_strdup(*file) : *file;
721 		page->names = NULL;
722 		page->output = NULL;
723 		page->bits = NAME_FILE & NAME_MASK;
724 		page->ipath = ipath;
725 		page->sec = (*sec >= '1' && *sec <= '9') ? *sec - '1' + 1 : 10;
726 		page->form = form;
727 		if (--filesz == 0)
728 			break;
729 		file++;
730 		page++;
731 	}
732 }
733 
734 static int
fs_lookup(const struct manpaths * paths,size_t ipath,const char * sec,const char * arch,const char * name,struct manpage ** res,size_t * ressz)735 fs_lookup(const struct manpaths *paths, size_t ipath,
736 	const char *sec, const char *arch, const char *name,
737 	struct manpage **res, size_t *ressz)
738 {
739 	struct stat	 sb;
740 	glob_t		 globinfo;
741 	char		*file, *cp, secnum[2];
742 	int		 globres;
743 	enum form	 form;
744 
745 	const char *const slman = "/man";
746 	const char *const slash = "/";
747 	const char *const sglob = ".[01-9]*";
748 	const char *const dot   = ".";
749 	const char *const aster = "*";
750 
751 	memset(&globinfo, 0, sizeof(globinfo));
752 	form = FORM_SRC;
753 
754 	mandoc_asprintf(&file, "%s/man%s/%s.%s",
755 	    paths->paths[ipath], sec, name, sec);
756 	if (stat(file, &sb) != -1)
757 		goto found;
758 	free(file);
759 
760 	mandoc_asprintf(&file, "%s/cat%s/%s.0",
761 	    paths->paths[ipath], sec, name);
762 	if (stat(file, &sb) != -1) {
763 		form = FORM_CAT;
764 		goto found;
765 	}
766 	free(file);
767 
768 	if (arch != NULL) {
769 		mandoc_asprintf(&file, "%s/man%s/%s/%s.%s",
770 		    paths->paths[ipath], sec, arch, name, sec);
771 		if (stat(file, &sb) != -1)
772 			goto found;
773 		free(file);
774 	}
775 
776 	cp = file = mandoc_malloc(strlen(paths->paths[ipath]) * 2 +
777 	    strlen(slman) + strlen(sec) * 2 + strlen(slash) +
778 	    strlen(name) * 2 + strlen(sglob) + 1);
779 	glob_esc(&cp, paths->paths[ipath], slman);
780 	glob_esc(&cp, sec, slash);
781 	glob_esc(&cp, name, sglob);
782 	*cp = '\0';
783 	globres = glob(file, 0, NULL, &globinfo);
784 	if (globres != 0 && globres != GLOB_NOMATCH)
785 		mandoc_msg(MANDOCERR_GLOB, 0, 0,
786 		    "%s: %s", file, strerror(errno));
787 	free(file);
788 	file = NULL;
789 	if (globres == 0)
790 		goto found;
791 	globfree(&globinfo);
792 
793 	if (sec[1] != '\0' && *ressz == 0) {
794 		secnum[0] = sec[0];
795 		secnum[1] = '\0';
796 		cp = file = mandoc_malloc(strlen(paths->paths[ipath]) * 2 +
797 		    strlen(slman) + strlen(secnum) * 2 + strlen(slash) +
798 		    strlen(name) * 2 + strlen(dot) +
799 		    strlen(sec) * 2 + strlen(aster) + 1);
800 		glob_esc(&cp, paths->paths[ipath], slman);
801 		glob_esc(&cp, secnum, slash);
802 		glob_esc(&cp, name, dot);
803 		glob_esc(&cp, sec, aster);
804 		*cp = '\0';
805 		globres = glob(file, 0, NULL, &globinfo);
806 		if (globres != 0 && globres != GLOB_NOMATCH)
807 			mandoc_msg(MANDOCERR_GLOB, 0, 0,
808 			    "%s: %s", file, strerror(errno));
809 		free(file);
810 		file = NULL;
811 		if (globres == 0)
812 			goto found;
813 		globfree(&globinfo);
814 	}
815 
816 	if (res != NULL || ipath + 1 != paths->sz)
817 		return -1;
818 
819 	mandoc_asprintf(&file, "%s.%s", name, sec);
820 	globres = stat(file, &sb);
821 	free(file);
822 	return globres;
823 
824 found:
825 	warnx("outdated mandoc.db lacks %s(%s) entry, run %s %s",
826 	    name, sec, BINM_MAKEWHATIS, paths->paths[ipath]);
827 	if (res == NULL)
828 		free(file);
829 	else if (file == NULL)
830 		fs_append(globinfo.gl_pathv, globinfo.gl_pathc, 1,
831 		    ipath, sec, form, res, ressz);
832 	else
833 		fs_append(&file, 1, 0, ipath, sec, form, res, ressz);
834 	globfree(&globinfo);
835 	return 0;
836 }
837 
838 static int
fs_search(const struct mansearch * cfg,const struct manpaths * paths,const char * name,struct manpage ** res,size_t * ressz)839 fs_search(const struct mansearch *cfg, const struct manpaths *paths,
840 	const char *name, struct manpage **res, size_t *ressz)
841 {
842 	const char *const sections[] =
843 	    {"1", "8", "6", "2", "3", "5", "7", "4", "9", "3p"};
844 	const size_t nsec = sizeof(sections)/sizeof(sections[0]);
845 
846 	size_t		 ipath, isec;
847 
848 	assert(cfg->argmode == ARG_NAME);
849 	if (res != NULL)
850 		*res = NULL;
851 	*ressz = 0;
852 	for (ipath = 0; ipath < paths->sz; ipath++) {
853 		if (cfg->sec != NULL) {
854 			if (fs_lookup(paths, ipath, cfg->sec, cfg->arch,
855 			    name, res, ressz) != -1 && cfg->firstmatch)
856 				return 0;
857 		} else {
858 			for (isec = 0; isec < nsec; isec++)
859 				if (fs_lookup(paths, ipath, sections[isec],
860 				    cfg->arch, name, res, ressz) != -1 &&
861 				    cfg->firstmatch)
862 					return 0;
863 		}
864 	}
865 	return -1;
866 }
867 
868 static void
process_onefile(struct mparse * mp,struct manpage * resp,int startdir,struct outstate * outst,struct manconf * conf)869 process_onefile(struct mparse *mp, struct manpage *resp, int startdir,
870     struct outstate *outst, struct manconf *conf)
871 {
872 	int	 fd;
873 
874 	/*
875 	 * Changing directories is not needed in ARG_FILE mode.
876 	 * Do it on a best-effort basis.  Even in case of
877 	 * failure, some functionality may still work.
878 	 */
879 	if (resp->ipath != SIZE_MAX)
880 		(void)chdir(conf->manpath.paths[resp->ipath]);
881 	else if (startdir != -1)
882 		(void)fchdir(startdir);
883 
884 	mandoc_msg_setinfilename(resp->file);
885 	if (resp->file != NULL) {
886 		if ((fd = mparse_open(mp, resp->file)) == -1) {
887 			mandoc_msg(resp->ipath == SIZE_MAX ?
888 			    MANDOCERR_BADARG_BAD : MANDOCERR_OPEN,
889 			    0, 0, "%s", strerror(errno));
890 			mandoc_msg_setinfilename(NULL);
891 			return;
892 		}
893 	} else
894 		fd = STDIN_FILENO;
895 
896 	if (outst->use_pager) {
897 		outst->use_pager = 0;
898 		outst->tag_files = term_tag_init(conf->output.outfilename,
899 		    outst->outtype == OUTT_HTML ? ".html" : "",
900 		    conf->output.tagfilename);
901 #if HAVE_PLEDGE
902 		if ((conf->output.outfilename != NULL ||
903 		     conf->output.tagfilename != NULL) &&
904 		    pledge("stdio rpath cpath", NULL) == -1) {
905 			mandoc_msg(MANDOCERR_PLEDGE, 0, 0,
906 			    "%s", strerror(errno));
907 			exit(mandoc_msg_getrc());
908 		}
909 #endif
910 	}
911 	if (outst->had_output && outst->outtype <= OUTT_UTF8) {
912 		if (outst->outdata == NULL)
913 			outdata_alloc(outst, &conf->output);
914 		terminal_sepline(outst->outdata);
915 	}
916 
917 	if (resp->form == FORM_SRC)
918 		parse(mp, fd, resp->file, outst, conf);
919 	else {
920 		passthrough(fd, conf->output.synopsisonly);
921 		outst->had_output = 1;
922 	}
923 
924 	if (ferror(stdout)) {
925 		if (outst->tag_files != NULL) {
926 			mandoc_msg(MANDOCERR_WRITE, 0, 0, "%s: %s",
927 			    outst->tag_files->ofn, strerror(errno));
928 			term_tag_unlink();
929 			outst->tag_files = NULL;
930 		} else
931 			mandoc_msg(MANDOCERR_WRITE, 0, 0, "%s",
932 			    strerror(errno));
933 	}
934 	mandoc_msg_setinfilename(NULL);
935 }
936 
937 static void
parse(struct mparse * mp,int fd,const char * file,struct outstate * outst,struct manconf * conf)938 parse(struct mparse *mp, int fd, const char *file,
939     struct outstate *outst, struct manconf *conf)
940 {
941 	static struct manpaths	 basepaths;
942 	static int		 previous;
943 	struct roff_meta	*meta;
944 
945 	assert(fd >= 0);
946 	if (file == NULL)
947 		file = "<stdin>";
948 
949 	if (previous)
950 		mparse_reset(mp);
951 	else
952 		previous = 1;
953 
954 	mparse_readfd(mp, fd, file);
955 	if (fd != STDIN_FILENO)
956 		close(fd);
957 
958 	/*
959 	 * With -Wstop and warnings or errors of at least the requested
960 	 * level, do not produce output.
961 	 */
962 
963 	if (outst->wstop && mandoc_msg_getrc() != MANDOCLEVEL_OK)
964 		return;
965 
966 	if (outst->outdata == NULL)
967 		outdata_alloc(outst, &conf->output);
968 	else if (outst->outtype == OUTT_HTML)
969 		html_reset(outst->outdata);
970 
971 	mandoc_xr_reset();
972 	meta = mparse_result(mp);
973 
974 	/* Execute the out device, if it exists. */
975 
976 	outst->had_output = 1;
977 	if (meta->macroset == MACROSET_MDOC) {
978 		switch (outst->outtype) {
979 		case OUTT_HTML:
980 			html_mdoc(outst->outdata, meta);
981 			break;
982 		case OUTT_TREE:
983 			tree_mdoc(outst->outdata, meta);
984 			break;
985 		case OUTT_MAN:
986 			man_mdoc(outst->outdata, meta);
987 			break;
988 		case OUTT_PDF:
989 		case OUTT_ASCII:
990 		case OUTT_UTF8:
991 		case OUTT_LOCALE:
992 		case OUTT_PS:
993 			terminal_mdoc(outst->outdata, meta);
994 			break;
995 		case OUTT_MARKDOWN:
996 			markdown_mdoc(outst->outdata, meta);
997 			break;
998 		default:
999 			break;
1000 		}
1001 	}
1002 	if (meta->macroset == MACROSET_MAN) {
1003 		switch (outst->outtype) {
1004 		case OUTT_HTML:
1005 			html_man(outst->outdata, meta);
1006 			break;
1007 		case OUTT_TREE:
1008 			tree_man(outst->outdata, meta);
1009 			break;
1010 		case OUTT_MAN:
1011 			mparse_copy(mp);
1012 			break;
1013 		case OUTT_PDF:
1014 		case OUTT_ASCII:
1015 		case OUTT_UTF8:
1016 		case OUTT_LOCALE:
1017 		case OUTT_PS:
1018 			terminal_man(outst->outdata, meta);
1019 			break;
1020 		case OUTT_MARKDOWN:
1021 			mandoc_msg(MANDOCERR_MAN_TMARKDOWN, 0, 0, NULL);
1022 			break;
1023 		default:
1024 			break;
1025 		}
1026 	}
1027 	if (conf->output.tag != NULL && conf->output.tag_found == 0 &&
1028 	    tag_exists(conf->output.tag))
1029 		conf->output.tag_found = 1;
1030 
1031 	if (mandoc_msg_getmin() < MANDOCERR_STYLE) {
1032 		if (basepaths.sz == 0)
1033 			manpath_base(&basepaths);
1034 		check_xr(&basepaths);
1035 	} else if (mandoc_msg_getmin() < MANDOCERR_WARNING)
1036 		check_xr(&conf->manpath);
1037 }
1038 
1039 static void
check_xr(struct manpaths * paths)1040 check_xr(struct manpaths *paths)
1041 {
1042 	struct mansearch	 search;
1043 	struct mandoc_xr	*xr;
1044 	size_t			 sz;
1045 
1046 	for (xr = mandoc_xr_get(); xr != NULL; xr = xr->next) {
1047 		if (xr->line == -1)
1048 			continue;
1049 		search.arch = NULL;
1050 		search.sec = xr->sec;
1051 		search.outkey = NULL;
1052 		search.argmode = ARG_NAME;
1053 		search.firstmatch = 1;
1054 		if (mansearch(&search, paths, 1, &xr->name, NULL, &sz))
1055 			continue;
1056 		if (fs_search(&search, paths, xr->name, NULL, &sz) != -1)
1057 			continue;
1058 		if (xr->count == 1)
1059 			mandoc_msg(MANDOCERR_XR_BAD, xr->line,
1060 			    xr->pos + 1, "Xr %s %s", xr->name, xr->sec);
1061 		else
1062 			mandoc_msg(MANDOCERR_XR_BAD, xr->line,
1063 			    xr->pos + 1, "Xr %s %s (%d times)",
1064 			    xr->name, xr->sec, xr->count);
1065 	}
1066 }
1067 
1068 static void
outdata_alloc(struct outstate * outst,struct manoutput * outconf)1069 outdata_alloc(struct outstate *outst, struct manoutput *outconf)
1070 {
1071 	switch (outst->outtype) {
1072 	case OUTT_HTML:
1073 		outst->outdata = html_alloc(outconf);
1074 		break;
1075 	case OUTT_UTF8:
1076 		outst->outdata = utf8_alloc(outconf);
1077 		break;
1078 	case OUTT_LOCALE:
1079 		outst->outdata = locale_alloc(outconf);
1080 		break;
1081 	case OUTT_ASCII:
1082 		outst->outdata = ascii_alloc(outconf);
1083 		break;
1084 	case OUTT_PDF:
1085 		outst->outdata = pdf_alloc(outconf);
1086 		break;
1087 	case OUTT_PS:
1088 		outst->outdata = ps_alloc(outconf);
1089 		break;
1090 	default:
1091 		break;
1092 	}
1093 }
1094 
1095 static void
passthrough(int fd,int synopsis_only)1096 passthrough(int fd, int synopsis_only)
1097 {
1098 	const char	 synb[] = "S\bSY\bYN\bNO\bOP\bPS\bSI\bIS\bS";
1099 	const char	 synr[] = "SYNOPSIS";
1100 
1101 	FILE		*stream;
1102 	char		*line, *cp;
1103 	size_t		 linesz;
1104 	ssize_t		 len, written;
1105 	int		 lno, print;
1106 
1107 	stream = NULL;
1108 	line = NULL;
1109 	linesz = 0;
1110 
1111 	if (fflush(stdout) == EOF) {
1112 		mandoc_msg(MANDOCERR_FFLUSH, 0, 0, "%s", strerror(errno));
1113 		goto done;
1114 	}
1115 	if ((stream = fdopen(fd, "r")) == NULL) {
1116 		close(fd);
1117 		mandoc_msg(MANDOCERR_FDOPEN, 0, 0, "%s", strerror(errno));
1118 		goto done;
1119 	}
1120 
1121 	lno = print = 0;
1122 	while ((len = getline(&line, &linesz, stream)) != -1) {
1123 		lno++;
1124 		cp = line;
1125 		if (synopsis_only) {
1126 			if (print) {
1127 				if ( ! isspace((unsigned char)*cp))
1128 					goto done;
1129 				while (isspace((unsigned char)*cp)) {
1130 					cp++;
1131 					len--;
1132 				}
1133 			} else {
1134 				if (strcmp(cp, synb) == 0 ||
1135 				    strcmp(cp, synr) == 0)
1136 					print = 1;
1137 				continue;
1138 			}
1139 		}
1140 		for (; len > 0; len -= written) {
1141 			if ((written = write(STDOUT_FILENO, cp, len)) == -1) {
1142 				mandoc_msg(MANDOCERR_WRITE, 0, 0,
1143 				    "%s", strerror(errno));
1144 				goto done;
1145 			}
1146 		}
1147 	}
1148 	if (ferror(stream))
1149 		mandoc_msg(MANDOCERR_GETLINE, lno, 0, "%s", strerror(errno));
1150 
1151 done:
1152 	free(line);
1153 	if (stream != NULL)
1154 		fclose(stream);
1155 }
1156 
1157 static int
woptions(char * arg,enum mandoc_os * os_e,int * wstop)1158 woptions(char *arg, enum mandoc_os *os_e, int *wstop)
1159 {
1160 	char		*v, *o;
1161 	const char	*toks[11];
1162 
1163 	toks[0] = "stop";
1164 	toks[1] = "all";
1165 	toks[2] = "base";
1166 	toks[3] = "style";
1167 	toks[4] = "warning";
1168 	toks[5] = "error";
1169 	toks[6] = "unsupp";
1170 	toks[7] = "fatal";
1171 	toks[8] = "openbsd";
1172 	toks[9] = "netbsd";
1173 	toks[10] = NULL;
1174 
1175 	while (*arg) {
1176 		o = arg;
1177 		switch (getsubopt(&arg, (char * const *)toks, &v)) {
1178 		case 0:
1179 			*wstop = 1;
1180 			break;
1181 		case 1:
1182 		case 2:
1183 			mandoc_msg_setmin(MANDOCERR_BASE);
1184 			break;
1185 		case 3:
1186 			mandoc_msg_setmin(MANDOCERR_STYLE);
1187 			break;
1188 		case 4:
1189 			mandoc_msg_setmin(MANDOCERR_WARNING);
1190 			break;
1191 		case 5:
1192 			mandoc_msg_setmin(MANDOCERR_ERROR);
1193 			break;
1194 		case 6:
1195 			mandoc_msg_setmin(MANDOCERR_UNSUPP);
1196 			break;
1197 		case 7:
1198 			mandoc_msg_setmin(MANDOCERR_BADARG);
1199 			break;
1200 		case 8:
1201 			mandoc_msg_setmin(MANDOCERR_BASE);
1202 			*os_e = MANDOC_OS_OPENBSD;
1203 			break;
1204 		case 9:
1205 			mandoc_msg_setmin(MANDOCERR_BASE);
1206 			*os_e = MANDOC_OS_NETBSD;
1207 			break;
1208 		default:
1209 			mandoc_msg(MANDOCERR_BADARG_BAD, 0, 0, "-W %s", o);
1210 			return -1;
1211 		}
1212 	}
1213 	return 0;
1214 }
1215 
1216 /*
1217  * Wait until moved to the foreground,
1218  * then fork the pager and wait for the user to close it.
1219  */
1220 static void
run_pager(struct outstate * outst,char * tag_target)1221 run_pager(struct outstate *outst, char *tag_target)
1222 {
1223 	int	 signum, status;
1224 	pid_t	 man_pgid, tc_pgid;
1225 	pid_t	 pager_pid, wait_pid;
1226 
1227 	man_pgid = getpgid(0);
1228 	outst->tag_files->tcpgid =
1229 	    man_pgid == getpid() ? getpgid(getppid()) : man_pgid;
1230 	pager_pid = 0;
1231 	signum = SIGSTOP;
1232 
1233 	for (;;) {
1234 		/* Stop here until moved to the foreground. */
1235 
1236 		tc_pgid = tcgetpgrp(STDOUT_FILENO);
1237 		if (tc_pgid != man_pgid) {
1238 			if (tc_pgid == pager_pid) {
1239 				(void)tcsetpgrp(STDOUT_FILENO, man_pgid);
1240 				if (signum == SIGTTIN)
1241 					continue;
1242 			} else
1243 				outst->tag_files->tcpgid = tc_pgid;
1244 			kill(0, signum);
1245 			continue;
1246 		}
1247 
1248 		/* Once in the foreground, activate the pager. */
1249 
1250 		if (pager_pid) {
1251 			(void)tcsetpgrp(STDOUT_FILENO, pager_pid);
1252 			kill(pager_pid, SIGCONT);
1253 		} else
1254 			pager_pid = spawn_pager(outst, tag_target);
1255 
1256 		/* Wait for the pager to stop or exit. */
1257 
1258 		while ((wait_pid = waitpid(pager_pid, &status,
1259 		    WUNTRACED)) == -1 && errno == EINTR)
1260 			continue;
1261 
1262 		if (wait_pid == -1) {
1263 			mandoc_msg(MANDOCERR_WAIT, 0, 0,
1264 			    "%s", strerror(errno));
1265 			break;
1266 		}
1267 		if (!WIFSTOPPED(status))
1268 			break;
1269 
1270 		signum = WSTOPSIG(status);
1271 	}
1272 }
1273 
1274 static pid_t
spawn_pager(struct outstate * outst,char * tag_target)1275 spawn_pager(struct outstate *outst, char *tag_target)
1276 {
1277 	const struct timespec timeout = { 0, 100000000 };  /* 0.1s */
1278 #define MAX_PAGER_ARGS 16
1279 	char		*argv[MAX_PAGER_ARGS];
1280 	const char	*pager;
1281 	char		*cp;
1282 #if HAVE_LESS_T
1283 	size_t		 cmdlen;
1284 #endif
1285 	int		 argc, use_ofn;
1286 	pid_t		 pager_pid;
1287 
1288 	assert(outst->tag_files->ofd == -1);
1289 	assert(outst->tag_files->tfs == NULL);
1290 
1291 	pager = getenv("MANPAGER");
1292 	if (pager == NULL || *pager == '\0')
1293 		pager = getenv("PAGER");
1294 	if (pager == NULL || *pager == '\0')
1295 		pager = BINM_PAGER;
1296 	cp = mandoc_strdup(pager);
1297 
1298 	/*
1299 	 * Parse the pager command into words.
1300 	 * Intentionally do not do anything fancy here.
1301 	 */
1302 
1303 	argc = 0;
1304 	while (argc + 5 < MAX_PAGER_ARGS) {
1305 		argv[argc++] = cp;
1306 		cp = strchr(cp, ' ');
1307 		if (cp == NULL)
1308 			break;
1309 		*cp++ = '\0';
1310 		while (*cp == ' ')
1311 			cp++;
1312 		if (*cp == '\0')
1313 			break;
1314 	}
1315 
1316 	/* For less(1), use the tag file. */
1317 
1318 	use_ofn = 1;
1319 #if HAVE_LESS_T
1320 	if (*outst->tag_files->tfn != '\0' &&
1321 	    (cmdlen = strlen(argv[0])) >= 4) {
1322 		cp = argv[0] + cmdlen - 4;
1323 		if (strcmp(cp, "less") == 0) {
1324 			argv[argc++] = mandoc_strdup("-T");
1325 			argv[argc++] = outst->tag_files->tfn;
1326 			if (tag_target != NULL) {
1327 				argv[argc++] = mandoc_strdup("-t");
1328 				argv[argc++] = tag_target;
1329 				use_ofn = 0;
1330 			}
1331 		}
1332 	}
1333 #endif
1334 	if (use_ofn) {
1335 		if (outst->outtype == OUTT_HTML && tag_target != NULL)
1336 			mandoc_asprintf(&argv[argc], "file://%s#%s",
1337 			    outst->tag_files->ofn, tag_target);
1338 		else
1339 			argv[argc] = outst->tag_files->ofn;
1340 		argc++;
1341 	}
1342 	argv[argc] = NULL;
1343 
1344 	switch (pager_pid = fork()) {
1345 	case -1:
1346 		mandoc_msg(MANDOCERR_FORK, 0, 0, "%s", strerror(errno));
1347 		exit(mandoc_msg_getrc());
1348 	case 0:
1349 		break;
1350 	default:
1351 		(void)setpgid(pager_pid, 0);
1352 		(void)tcsetpgrp(STDOUT_FILENO, pager_pid);
1353 #if HAVE_PLEDGE
1354 		if (pledge("stdio rpath tmppath tty proc", NULL) == -1) {
1355 			mandoc_msg(MANDOCERR_PLEDGE, 0, 0,
1356 			    "%s", strerror(errno));
1357 			exit(mandoc_msg_getrc());
1358 		}
1359 #endif
1360 		outst->tag_files->pager_pid = pager_pid;
1361 		return pager_pid;
1362 	}
1363 
1364 	/*
1365 	 * The child process becomes the pager.
1366 	 * Do not start it before controlling the terminal.
1367 	 */
1368 
1369 	while (tcgetpgrp(STDOUT_FILENO) != getpid())
1370 		nanosleep(&timeout, NULL);
1371 
1372 	execvp(argv[0], argv);
1373 	mandoc_msg(MANDOCERR_EXEC, 0, 0, "%s: %s", argv[0], strerror(errno));
1374 	_exit(mandoc_msg_getrc());
1375 }
1376