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man.c revision 1.35.4.1
      1 /*	$NetBSD: man.c,v 1.35.4.1 2007/11/06 23:36:06 matt Exp $	*/
      2 
      3 /*
      4  * Copyright (c) 1987, 1993, 1994, 1995
      5  *	The Regents of the University of California.  All rights reserved.
      6  *
      7  * Redistribution and use in source and binary forms, with or without
      8  * modification, are permitted provided that the following conditions
      9  * are met:
     10  * 1. Redistributions of source code must retain the above copyright
     11  *    notice, this list of conditions and the following disclaimer.
     12  * 2. Redistributions in binary form must reproduce the above copyright
     13  *    notice, this list of conditions and the following disclaimer in the
     14  *    documentation and/or other materials provided with the distribution.
     15  * 3. Neither the name of the University nor the names of its contributors
     16  *    may be used to endorse or promote products derived from this software
     17  *    without specific prior written permission.
     18  *
     19  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
     20  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
     21  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
     22  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
     23  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
     24  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
     25  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
     26  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
     27  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
     28  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
     29  * SUCH DAMAGE.
     30  */
     31 
     32 #include <sys/cdefs.h>
     33 
     34 #ifndef lint
     35 __COPYRIGHT("@(#) Copyright (c) 1987, 1993, 1994, 1995\n\
     36 	The Regents of the University of California.  All rights reserved.\n");
     37 #endif /* not lint */
     38 
     39 #ifndef lint
     40 #if 0
     41 static char sccsid[] = "@(#)man.c	8.17 (Berkeley) 1/31/95";
     42 #else
     43 __RCSID("$NetBSD: man.c,v 1.35.4.1 2007/11/06 23:36:06 matt Exp $");
     44 #endif
     45 #endif /* not lint */
     46 
     47 #include <sys/param.h>
     48 #include <sys/queue.h>
     49 #include <sys/utsname.h>
     50 
     51 #include <ctype.h>
     52 #include <err.h>
     53 #include <errno.h>
     54 #include <fcntl.h>
     55 #include <fnmatch.h>
     56 #include <glob.h>
     57 #include <signal.h>
     58 #include <stdio.h>
     59 #include <stdlib.h>
     60 #include <string.h>
     61 #include <unistd.h>
     62 #include <util.h>
     63 
     64 #include "manconf.h"
     65 #include "pathnames.h"
     66 
     67 #ifndef MAN_DEBUG
     68 #define MAN_DEBUG 0		/* debug path output */
     69 #endif
     70 
     71 /*
     72  * manstate: structure collecting the current global state so we can
     73  * easily identify it and pass it to helper functions in one arg.
     74  */
     75 struct manstate {
     76 	/* command line flags */
     77 	int all;		/* -a: show all matches rather than first */
     78 	int cat;		/* -c: do not use a pager */
     79 	char *conffile;		/* -C: use alternate config file */
     80 	int how;		/* -h: show SYNOPSIS only */
     81 	char *manpath;		/* -M: alternate MANPATH */
     82 	char *addpath;		/* -m: add these dirs to front of manpath */
     83 	char *pathsearch;	/* -S: path of man must contain this string */
     84 	char *sectionname;	/* -s: limit search to a given man section */
     85 	int where;		/* -w: just show paths of all matching files */
     86 
     87 	/* important tags from the config file */
     88 	TAG *defaultpath;	/* _default: default MANPATH */
     89 	TAG *subdirs;		/* _subdir: default subdir search list */
     90 	TAG *suffixlist;	/* _suffix: for files that can be cat()'d */
     91 	TAG *buildlist;		/* _build: for files that must be built */
     92 
     93 	/* tags for internal use */
     94 	TAG *intmp;		/* _intmp: tmp files we must cleanup */
     95 	TAG *missinglist;	/* _missing: pages we couldn't find */
     96 	TAG *mymanpath;		/* _new_path: final version of MANPATH */
     97 	TAG *section;		/* <sec>: tag for m.sectionname */
     98 
     99 	/* other misc stuff */
    100 	const char *pager;	/* pager to use */
    101 	size_t pagerlen;	/* length of the above */
    102 };
    103 
    104 /*
    105  * prototypes
    106  */
    107 int		 main(int, char **);
    108 static void	 build_page(char *, char **, struct manstate *);
    109 static void	 cat(char *);
    110 static const char	*check_pager(const char *);
    111 static int	 cleanup(void);
    112 static void	 how(char *);
    113 static void	 jump(char **, char *, char *);
    114 static int	 manual(char *, struct manstate *, glob_t *);
    115 static void	 onsig(int);
    116 static void	 usage(void);
    117 
    118 /*
    119  * main function
    120  */
    121 int
    122 main(int argc, char **argv)
    123 {
    124 	static struct manstate m = { 0 }; 	/* init to zero */
    125 	int ch, abs_section, found;
    126 	const char *machine;
    127 	ENTRY *esubd, *epath;
    128 	char *p, **ap, *cmd, buf[MAXPATHLEN * 2];
    129 	size_t len;
    130 	glob_t pg;
    131 
    132 	/*
    133 	 * parse command line...
    134 	 */
    135 	while ((ch = getopt(argc, argv, "-aC:cfhkM:m:P:s:S:w")) != -1)
    136 		switch (ch) {
    137 		case 'a':
    138 			m.all = 1;
    139 			break;
    140 		case 'C':
    141 			m.conffile = optarg;
    142 			break;
    143 		case 'c':
    144 		case '-':	/* XXX: '-' is a deprecated version of '-c' */
    145 			m.cat = 1;
    146 			break;
    147 		case 'h':
    148 			m.how = 1;
    149 			break;
    150 		case 'm':
    151 			m.addpath = optarg;
    152 			break;
    153 		case 'M':
    154 		case 'P':	/* -P for backward compatibility */
    155 			m.manpath = strdup(optarg);
    156 			break;
    157 		/*
    158 		 * The -f and -k options are backward compatible,
    159 		 * undocumented ways of calling whatis(1) and apropos(1).
    160 		 */
    161 		case 'f':
    162 			jump(argv, "-f", "whatis");
    163 			/* NOTREACHED */
    164 		case 'k':
    165 			jump(argv, "-k", "apropos");
    166 			/* NOTREACHED */
    167 		case 's':
    168 			if (m.sectionname != NULL)
    169 				usage();
    170 			m.sectionname = optarg;
    171 			break;
    172 		case 'S':
    173 			m.pathsearch = optarg;
    174 			break;
    175 		case 'w':
    176 			m.all = m.where = 1;
    177 			break;
    178 		case '?':
    179 		default:
    180 			usage();
    181 		}
    182 	argc -= optind;
    183 	argv += optind;
    184 
    185 	if (!argc)
    186 		usage();
    187 
    188 	/*
    189 	 * read the configuration file and collect any other information
    190 	 * we will need (machine type, pager, section [if specified
    191 	 * without '-s'], and MANPATH through the environment).
    192 	 */
    193 	config(m.conffile);    /* exits on error ... */
    194 
    195 	if ((machine = getenv("MACHINE")) == NULL) {
    196 		struct utsname utsname;
    197 
    198 		if (uname(&utsname) == -1) {
    199 			perror("uname");
    200 			exit(1);
    201 		}
    202 		machine = utsname.machine;
    203 	}
    204 
    205 	if (!m.cat && !m.how && !m.where) {  /* if we need a pager ... */
    206 		if (!isatty(STDOUT_FILENO)) {
    207 			m.cat = 1;
    208 		} else {
    209 			if ((m.pager = getenv("PAGER")) != NULL &&
    210 			    m.pager[0] != '\0')
    211 				m.pager = check_pager(m.pager);
    212 			else
    213 				m.pager = _PATH_PAGER;
    214 			m.pagerlen = strlen(m.pager);
    215 		}
    216 	}
    217 
    218 	/* do we need to set m.section to a non-null value? */
    219 	if (m.sectionname) {
    220 
    221 		m.section = gettag(m.sectionname, 0); /* -s must be a section */
    222 		if (m.section == NULL)
    223 			errx(1, "unknown section: %s", m.sectionname);
    224 
    225 	} else if (argc > 1) {
    226 
    227 		m.section = gettag(*argv, 0);  /* might be a section? */
    228 		if (m.section) {
    229 			argv++;
    230 			argc--;
    231 		}
    232 
    233 	}
    234 
    235 	if (m.manpath == NULL)
    236 		m.manpath = getenv("MANPATH"); /* note: -M overrides getenv */
    237 
    238 
    239 	/*
    240 	 * get default values from config file, plus create the tags we
    241 	 * use for keeping internal state.  make sure all our mallocs
    242 	 * go through.
    243 	 */
    244 	/* from cfg file */
    245 	m.defaultpath = gettag("_default", 1);
    246 	m.subdirs = gettag("_subdir", 1);
    247 	m.suffixlist = gettag("_suffix", 1);
    248 	m.buildlist = gettag("_build", 1);
    249 	/* internal use */
    250 	m.mymanpath = gettag("_new_path", 1);
    251 	m.missinglist = gettag("_missing", 1);
    252 	m.intmp = gettag("_intmp", 1);
    253 	if (!m.defaultpath || !m.subdirs || !m.suffixlist || !m.buildlist ||
    254 	    !m.mymanpath || !m.missinglist || !m.intmp)
    255 		errx(1, "malloc failed");
    256 
    257 	/*
    258 	 * are we using a section whose elements are all absolute paths?
    259 	 * (we only need to look at the first entry on the section list,
    260 	 * as config() will ensure that any additional entries will match
    261 	 * the first one.)
    262 	 */
    263 	abs_section = (m.section != NULL &&
    264 		!TAILQ_EMPTY(&m.section->entrylist) &&
    265 	    		*(TAILQ_FIRST(&m.section->entrylist)->s) == '/');
    266 
    267 	/*
    268 	 * now that we have all the data we need, we must determine the
    269 	 * manpath we are going to use to find the requested entries using
    270 	 * the following steps...
    271 	 *
    272 	 * [1] if the user specified a section and that section's elements
    273 	 *     from the config file are all absolute paths, then we override
    274 	 *     defaultpath and -M/MANPATH with the section's absolute paths.
    275 	 */
    276 	if (abs_section) {
    277 		m.manpath = NULL;	   	/* ignore -M/MANPATH */
    278 		m.defaultpath = m.section;	/* overwrite _default path */
    279 		m.section = NULL;		/* promoted to defaultpath */
    280 	}
    281 
    282 	/*
    283 	 * [2] section can now only be non-null if the user asked for
    284 	 *     a section and that section's elements did not have
    285          *     absolute paths.  in this case we use the section's
    286 	 *     elements to override _subdir from the config file.
    287 	 *
    288 	 * after this step, we are done processing "m.section"...
    289 	 */
    290 	if (m.section)
    291 		m.subdirs = m.section;
    292 
    293 	/*
    294 	 * [3] we need to setup the path we want to use (m.mymanpath).
    295 	 *     if the user gave us a path (m.manpath) use it, otherwise
    296 	 *     go with the default.   in either case we need to append
    297 	 *     the subdir and machine spec to each element of the path.
    298 	 *
    299 	 *     for absolute section paths that come from the config file,
    300 	 *     we only append the subdir spec if the path ends in
    301 	 *     a '/' --- elements that do not end in '/' are assumed to
    302 	 *     not have subdirectories.  this is mainly for backward compat,
    303 	 *     but it allows non-subdir configs like:
    304 	 *	sect3       /usr/share/man/{old/,}cat3
    305 	 *	doc         /usr/{pkg,share}/doc/{sendmail/op,sendmail/intro}
    306 	 *
    307 	 *     note that we try and be careful to not put double slashes
    308 	 *     in the path (e.g. we want /usr/share/man/man1, not
    309 	 *     /usr/share/man//man1) because "more" will put the filename
    310 	 *     we generate in its prompt and the double slashes look ugly.
    311 	 */
    312 	if (m.manpath) {
    313 
    314 		/* note: strtok is going to destroy m.manpath */
    315 		for (p = strtok(m.manpath, ":") ; p ; p = strtok(NULL, ":")) {
    316 			len = strlen(p);
    317 			if (len < 1)
    318 				continue;
    319 			TAILQ_FOREACH(esubd, &m.subdirs->entrylist, q) {
    320 				snprintf(buf, sizeof(buf), "%s%s%s{/%s,}",
    321 					 p, (p[len-1] == '/') ? "" : "/",
    322 					 esubd->s, machine);
    323 				if (addentry(m.mymanpath, buf, 0) < 0)
    324 					errx(1, "malloc failed");
    325 			}
    326 		}
    327 
    328 	} else {
    329 
    330 		TAILQ_FOREACH(epath, &m.defaultpath->entrylist, q) {
    331 			/* handle trailing "/" magic here ... */
    332 		  	if (abs_section &&
    333 			    epath->s[epath->len - 1] != '/') {
    334 
    335 				(void)snprintf(buf, sizeof(buf),
    336 				    "%s{/%s,}", epath->s, machine);
    337 				if (addentry(m.mymanpath, buf, 0) < 0)
    338 					errx(1, "malloc failed");
    339 				continue;
    340 			}
    341 
    342 			TAILQ_FOREACH(esubd, &m.subdirs->entrylist, q) {
    343 				snprintf(buf, sizeof(buf), "%s%s%s{/%s,}",
    344 					 epath->s,
    345 					 (epath->s[epath->len-1] == '/') ? ""
    346 									 : "/",
    347 					 esubd->s, machine);
    348 				if (addentry(m.mymanpath, buf, 0) < 0)
    349 					errx(1, "malloc failed");
    350 			}
    351 		}
    352 
    353 	}
    354 
    355 	/*
    356 	 * [4] finally, prepend the "-m" m.addpath to mymanpath if it
    357 	 *     was specified.   subdirs and machine are always applied to
    358 	 *     m.addpath.
    359 	 */
    360 	if (m.addpath) {
    361 
    362 		/* note: strtok is going to destroy m.addpath */
    363 		for (p = strtok(m.addpath, ":") ; p ; p = strtok(NULL, ":")) {
    364 			len = strlen(p);
    365 			if (len < 1)
    366 				continue;
    367 			TAILQ_FOREACH(esubd, &m.subdirs->entrylist, q) {
    368 				snprintf(buf, sizeof(buf), "%s%s%s{/%s,}",
    369 					 p, (p[len-1] == '/') ? "" : "/",
    370 					 esubd->s, machine);
    371 				/* add at front */
    372 				if (addentry(m.mymanpath, buf, 1) < 0)
    373 					errx(1, "malloc failed");
    374 			}
    375 		}
    376 
    377 	}
    378 
    379 	/*
    380 	 * now m.mymanpath is complete!
    381 	 */
    382 #if MAN_DEBUG
    383 	printf("mymanpath:\n");
    384 	TAILQ_FOREACH(epath, &m.mymanpath->entrylist, q) {
    385 		printf("\t%s\n", epath->s);
    386 	}
    387 #endif
    388 
    389 	/*
    390 	 * start searching for matching files and format them if necessary.
    391 	 * setup an interrupt handler so that we can ensure that temporary
    392 	 * files go away.
    393 	 */
    394 	(void)signal(SIGINT, onsig);
    395 	(void)signal(SIGHUP, onsig);
    396 	(void)signal(SIGPIPE, onsig);
    397 
    398 	memset(&pg, 0, sizeof(pg));
    399 	for (found = 0; *argv; ++argv)
    400 		if (manual(*argv, &m, &pg)) {
    401 			found = 1;
    402 		}
    403 
    404 	/* if nothing found, we're done. */
    405 	if (!found) {
    406 		(void)cleanup();
    407 		exit (1);
    408 	}
    409 
    410 	/*
    411 	 * handle the simple display cases first (m.cat, m.how, m.where)
    412 	 */
    413 	if (m.cat) {
    414 		for (ap = pg.gl_pathv; *ap != NULL; ++ap) {
    415 			if (**ap == '\0')
    416 				continue;
    417 			cat(*ap);
    418 		}
    419 		exit (cleanup());
    420 	}
    421 	if (m.how) {
    422 		for (ap = pg.gl_pathv; *ap != NULL; ++ap) {
    423 			if (**ap == '\0')
    424 				continue;
    425 			how(*ap);
    426 		}
    427 		exit(cleanup());
    428 	}
    429 	if (m.where) {
    430 		for (ap = pg.gl_pathv; *ap != NULL; ++ap) {
    431 			if (**ap == '\0')
    432 				continue;
    433 			(void)printf("%s\n", *ap);
    434 		}
    435 		exit(cleanup());
    436 	}
    437 
    438 	/*
    439 	 * normal case - we display things in a single command, so
    440          * build a list of things to display.  first compute total
    441 	 * length of buffer we will need so we can malloc it.
    442 	 */
    443 	for (ap = pg.gl_pathv, len = m.pagerlen + 1; *ap != NULL; ++ap) {
    444 		if (**ap == '\0')
    445 			continue;
    446 		len += strlen(*ap) + 1;
    447 	}
    448 	if ((cmd = malloc(len)) == NULL) {
    449 		warn("malloc");
    450 		(void)cleanup();
    451 		exit(1);
    452 	}
    453 
    454 	/* now build the command string... */
    455 	p = cmd;
    456 	len = m.pagerlen;
    457 	memcpy(p, m.pager, len);
    458 	p += len;
    459 	*p++ = ' ';
    460 	for (ap = pg.gl_pathv; *ap != NULL; ++ap) {
    461 		if (**ap == '\0')
    462 			continue;
    463 		len = strlen(*ap);
    464 		memcpy(p, *ap, len);
    465 		p += len;
    466 		*p++ = ' ';
    467 	}
    468 	*--p = '\0';
    469 
    470 	/* Use system(3) in case someone's pager is "pager arg1 arg2". */
    471 	(void)system(cmd);
    472 
    473 	exit(cleanup());
    474 }
    475 
    476 /*
    477  * manual --
    478  *	Search the manuals for the pages.
    479  */
    480 static int
    481 manual(char *page, struct manstate *mp, glob_t *pg)
    482 {
    483 	ENTRY *suffix, *mdir;
    484 	int anyfound, error, found;
    485 	size_t cnt;
    486 	char *p, buf[MAXPATHLEN], *escpage, *eptr;
    487 	static const char escglob[] = "\\~?*{}[]";
    488 
    489 	anyfound = 0;
    490 
    491 	/*
    492 	 * Fixup page which may contain glob(3) special characters, e.g.
    493 	 * the famous "No man page for [" FAQ.
    494 	 */
    495 	if ((escpage = malloc((2 * strlen(page)) + 1)) == NULL) {
    496 		warn("malloc");
    497 		(void)cleanup();
    498 		exit(1);
    499 	}
    500 
    501 	p = page;
    502 	eptr = escpage;
    503 
    504 	while (*p) {
    505 		if (strchr(escglob, *p) != NULL) {
    506 			*eptr++ = '\\';
    507 			*eptr++ = *p++;
    508 		} else
    509 			*eptr++ = *p++;
    510 	}
    511 
    512 	*eptr = '\0';
    513 
    514 	/* For each man directory in mymanpath ... */
    515 	TAILQ_FOREACH(mdir, &mp->mymanpath->entrylist, q) {
    516 
    517 		/*
    518 		 * use glob(3) to look in the filesystem for matching files.
    519 		 * match any suffix here, as we will check that later.
    520 		 */
    521 		(void)snprintf(buf, sizeof(buf), "%s/%s.*", mdir->s, escpage);
    522 		if ((error = glob(buf,
    523 		    GLOB_APPEND | GLOB_BRACE | GLOB_NOSORT, NULL, pg)) != 0) {
    524 			if (error == GLOB_NOMATCH)
    525 				continue;
    526 			else {
    527 				warn("globbing");
    528 				(void)cleanup();
    529 				exit(1);
    530 			}
    531 		}
    532 		if (pg->gl_matchc == 0)
    533 			continue;
    534 
    535 		/*
    536 		 * start going through the matches glob(3) just found and
    537 		 * use m.pathsearch (if present) to filter out pages we
    538 		 * don't want.  then verify the suffix is valid, and build
    539 		 * the page if we have a _build suffix.
    540 		 */
    541 		for (cnt = pg->gl_pathc - pg->gl_matchc;
    542 		    cnt < pg->gl_pathc; ++cnt) {
    543 
    544 			/* filter on directory path name */
    545 			if (mp->pathsearch) {
    546 				p = strstr(pg->gl_pathv[cnt], mp->pathsearch);
    547 				if (!p || strchr(p, '/') == NULL) {
    548 					pg->gl_pathv[cnt] = ""; /* zap! */
    549 					continue;
    550 				}
    551 			}
    552 
    553 			/*
    554 			 * Try the _suffix key words first.
    555 			 *
    556 			 * XXX
    557 			 * Older versions of man.conf didn't have the suffix
    558 			 * key words, it was assumed that everything was a .0.
    559 			 * We just test for .0 first, it's fast and probably
    560 			 * going to hit.
    561 			 */
    562 			(void)snprintf(buf, sizeof(buf), "*/%s.0", escpage);
    563 			if (!fnmatch(buf, pg->gl_pathv[cnt], 0))
    564 				goto next;
    565 
    566 			found = 0;
    567 			TAILQ_FOREACH(suffix, &mp->suffixlist->entrylist, q) {
    568 				(void)snprintf(buf,
    569 				     sizeof(buf), "*/%s%s", escpage,
    570 				     suffix->s);
    571 				if (!fnmatch(buf, pg->gl_pathv[cnt], 0)) {
    572 					found = 1;
    573 					break;
    574 				}
    575 			}
    576 			if (found)
    577 				goto next;
    578 
    579 			/* Try the _build key words next. */
    580 			found = 0;
    581 			TAILQ_FOREACH(suffix, &mp->buildlist->entrylist, q) {
    582 				for (p = suffix->s;
    583 				    *p != '\0' && !isspace((unsigned char)*p);
    584 				    ++p)
    585 					continue;
    586 				if (*p == '\0')
    587 					continue;
    588 				*p = '\0';
    589 				(void)snprintf(buf,
    590 				     sizeof(buf), "*/%s%s", escpage,
    591 				     suffix->s);
    592 				if (!fnmatch(buf, pg->gl_pathv[cnt], 0)) {
    593 					if (!mp->where)
    594 						build_page(p + 1,
    595 						    &pg->gl_pathv[cnt], mp);
    596 					*p = ' ';
    597 					found = 1;
    598 					break;
    599 				}
    600 				*p = ' ';
    601 			}
    602 			if (found) {
    603 next:				anyfound = 1;
    604 				if (!mp->all) {
    605 					/* Delete any other matches. */
    606 					while (++cnt< pg->gl_pathc)
    607 						pg->gl_pathv[cnt] = "";
    608 					break;
    609 				}
    610 				continue;
    611 			}
    612 
    613 			/* It's not a man page, forget about it. */
    614 			pg->gl_pathv[cnt] = "";
    615 		}
    616 
    617 		if (anyfound && !mp->all)
    618 			break;
    619 	}
    620 
    621 	/* If not found, enter onto the missing list. */
    622 	if (!anyfound) {
    623 		if (addentry(mp->missinglist, page, 0) < 0) {
    624 			warn("malloc");
    625 			(void)cleanup();
    626 			exit(1);
    627 		}
    628 	}
    629 
    630 	free(escpage);
    631 	return (anyfound);
    632 }
    633 
    634 /*
    635  * build_page --
    636  *	Build a man page for display.
    637  */
    638 static void
    639 build_page(char *fmt, char **pathp, struct manstate *mp)
    640 {
    641 	static int warned;
    642 	int olddir, fd, n, tmpdirlen;
    643 	char *p, *b;
    644 	char buf[MAXPATHLEN], cmd[MAXPATHLEN], tpath[MAXPATHLEN];
    645 	const char *tmpdir;
    646 
    647 	/* Let the user know this may take awhile. */
    648 	if (!warned) {
    649 		warned = 1;
    650 		warnx("Formatting manual page...");
    651 	}
    652 
    653        /*
    654         * Historically man chdir'd to the root of the man tree.
    655         * This was used in man pages that contained relative ".so"
    656         * directives (including other man pages for command aliases etc.)
    657         * It even went one step farther, by examining the first line
    658         * of the man page and parsing the .so filename so it would
    659         * make hard(?) links to the cat'ted man pages for space savings.
    660         * (We don't do that here, but we could).
    661         */
    662 
    663        /* copy and find the end */
    664        for (b = buf, p = *pathp; (*b++ = *p++) != '\0';)
    665                continue;
    666 
    667 	/*
    668 	 * skip the last two path components, page name and man[n] ...
    669 	 * (e.g. buf will be "/usr/share/man" and p will be "man1/man.1")
    670 	 * we also save a pointer to our current directory so that we
    671 	 * can fchdir() back to it.  this allows relative MANDIR paths
    672 	 * to work with multiple man pages... e.g. consider:
    673 	 *   	cd /usr/share && man -M ./man cat ls
    674 	 * when no "cat1" subdir files are present.
    675 	 */
    676 	olddir = -1;
    677 	for (--b, --p, n = 2; b != buf; b--, p--)
    678 		if (*b == '/')
    679 			if (--n == 0) {
    680 				*b = '\0';
    681 				olddir = open(".", O_RDONLY);
    682 				(void) chdir(buf);
    683 				p++;
    684 				break;
    685 			}
    686 
    687 
    688 	/* advance fmt pass the suffix spec to the printf format string */
    689 	for (; *fmt && isspace((unsigned char)*fmt); ++fmt)
    690 		continue;
    691 
    692 	/*
    693 	 * Get a temporary file and build a version of the file
    694 	 * to display.  Replace the old file name with the new one.
    695 	 */
    696 	if ((tmpdir = getenv("TMPDIR")) == NULL)
    697 		tmpdir = _PATH_TMP;
    698 	tmpdirlen = strlen(tmpdir);
    699 	(void)snprintf(tpath, sizeof (tpath), "%s%s%s", tmpdir,
    700 	    (tmpdirlen && tmpdir[tmpdirlen-1] == '/') ? "" : "/", TMPFILE);
    701 	if ((fd = mkstemp(tpath)) == -1) {
    702 		warn("%s", tpath);
    703 		(void)cleanup();
    704 		exit(1);
    705 	}
    706 	(void)snprintf(buf, sizeof(buf), "%s > %s", fmt, tpath);
    707 	(void)snprintf(cmd, sizeof(cmd), buf, p);
    708 	(void)system(cmd);
    709 	(void)close(fd);
    710 	if ((*pathp = strdup(tpath)) == NULL) {
    711 		warn("malloc");
    712 		(void)cleanup();
    713 		exit(1);
    714 	}
    715 
    716 	/* Link the built file into the remove-when-done list. */
    717 	if (addentry(mp->intmp, *pathp, 0) < 0) {
    718 		warn("malloc");
    719 		(void)cleanup();
    720 		exit(1);
    721 	}
    722 
    723 	/* restore old directory so relative manpaths still work */
    724 	if (olddir != -1) {
    725 		fchdir(olddir);
    726 		close(olddir);
    727 	}
    728 }
    729 
    730 /*
    731  * how --
    732  *	display how information
    733  */
    734 static void
    735 how(char *fname)
    736 {
    737 	FILE *fp;
    738 
    739 	int lcnt, print;
    740 	char *p, buf[256];
    741 
    742 	if (!(fp = fopen(fname, "r"))) {
    743 		warn("%s", fname);
    744 		(void)cleanup();
    745 		exit (1);
    746 	}
    747 #define	S1	"SYNOPSIS"
    748 #define	S2	"S\bSY\bYN\bNO\bOP\bPS\bSI\bIS\bS"
    749 #define	D1	"DESCRIPTION"
    750 #define	D2	"D\bDE\bES\bSC\bCR\bRI\bIP\bPT\bTI\bIO\bON\bN"
    751 	for (lcnt = print = 0; fgets(buf, sizeof(buf), fp);) {
    752 		if (!strncmp(buf, S1, sizeof(S1) - 1) ||
    753 		    !strncmp(buf, S2, sizeof(S2) - 1)) {
    754 			print = 1;
    755 			continue;
    756 		} else if (!strncmp(buf, D1, sizeof(D1) - 1) ||
    757 		    !strncmp(buf, D2, sizeof(D2) - 1)) {
    758 			if (fp)
    759 				(void)fclose(fp);
    760 			return;
    761 		}
    762 		if (!print)
    763 			continue;
    764 		if (*buf == '\n')
    765 			++lcnt;
    766 		else {
    767 			for(; lcnt; --lcnt)
    768 				(void)putchar('\n');
    769 			for (p = buf; isspace((unsigned char)*p); ++p)
    770 				continue;
    771 			(void)fputs(p, stdout);
    772 		}
    773 	}
    774 	(void)fclose(fp);
    775 }
    776 
    777 /*
    778  * cat --
    779  *	cat out the file
    780  */
    781 static void
    782 cat(char *fname)
    783 {
    784 	int fd, n;
    785 	char buf[2048];
    786 
    787 	if ((fd = open(fname, O_RDONLY, 0)) < 0) {
    788 		warn("%s", fname);
    789 		(void)cleanup();
    790 		exit(1);
    791 	}
    792 	while ((n = read(fd, buf, sizeof(buf))) > 0)
    793 		if (write(STDOUT_FILENO, buf, n) != n) {
    794 			warn("write");
    795 			(void)cleanup();
    796 			exit (1);
    797 		}
    798 	if (n == -1) {
    799 		warn("read");
    800 		(void)cleanup();
    801 		exit(1);
    802 	}
    803 	(void)close(fd);
    804 }
    805 
    806 /*
    807  * check_pager --
    808  *	check the user supplied page information
    809  */
    810 static const char *
    811 check_pager(const char *name)
    812 {
    813 	const char *p;
    814 
    815 	/*
    816 	 * if the user uses "more", we make it "more -s"; watch out for
    817 	 * PAGER = "mypager /usr/ucb/more"
    818 	 */
    819 	for (p = name; *p && !isspace((unsigned char)*p); ++p)
    820 		continue;
    821 	for (; p > name && *p != '/'; --p);
    822 	if (p != name)
    823 		++p;
    824 
    825 	/* make sure it's "more", not "morex" */
    826 	if (!strncmp(p, "more", 4) && (!p[4] || isspace((unsigned char)p[4]))){
    827 		char *newname;
    828 		(void)asprintf(&newname, "%s %s", p, "-s");
    829 		name = newname;
    830 	}
    831 
    832 	return (name);
    833 }
    834 
    835 /*
    836  * jump --
    837  *	strip out flag argument and jump
    838  */
    839 static void
    840 jump(char **argv, char *flag, char *name)
    841 {
    842 	char **arg;
    843 
    844 	argv[0] = name;
    845 	for (arg = argv + 1; *arg; ++arg)
    846 		if (!strcmp(*arg, flag))
    847 			break;
    848 	for (; *arg; ++arg)
    849 		arg[0] = arg[1];
    850 	execvp(name, argv);
    851 	(void)fprintf(stderr, "%s: Command not found.\n", name);
    852 	exit(1);
    853 }
    854 
    855 /*
    856  * onsig --
    857  *	If signaled, delete the temporary files.
    858  */
    859 static void
    860 onsig(int signo)
    861 {
    862 
    863 	(void)cleanup();
    864 
    865 	(void)raise_default_signal(signo);
    866 
    867 	/* NOTREACHED */
    868 	exit (1);
    869 }
    870 
    871 /*
    872  * cleanup --
    873  *	Clean up temporary files, show any error messages.
    874  */
    875 static int
    876 cleanup()
    877 {
    878 	TAG *intmpp, *missp;
    879 	ENTRY *ep;
    880 	int rval;
    881 
    882 	rval = 0;
    883 	/*
    884 	 * note that _missing and _intmp were created by main(), so
    885 	 * gettag() cannot return NULL here.
    886 	 */
    887 	missp = gettag("_missing", 0);	/* missing man pages */
    888 	intmpp = gettag("_intmp", 0);	/* tmp files we need to unlink */
    889 
    890 	TAILQ_FOREACH(ep, &missp->entrylist, q) {
    891 		warnx("no entry for %s in the manual.", ep->s);
    892 		rval = 1;
    893 	}
    894 
    895 	TAILQ_FOREACH(ep, &intmpp->entrylist, q)
    896 		(void)unlink(ep->s);
    897 
    898 	return (rval);
    899 }
    900 
    901 /*
    902  * usage --
    903  *	print usage message and die
    904  */
    905 static void
    906 usage()
    907 {
    908 	(void)fprintf(stderr, "usage: %s [-acw|-h] [-C cfg] [-M path] "
    909 	    "[-m path] [-S srch] [[-s] sect] name ...\n", getprogname());
    910 	(void)fprintf(stderr,
    911 	    "usage: %s -k [-C cfg] [-M path] [-m path] keyword ...\n",
    912 	    getprogname());
    913 	exit(1);
    914 }
    915