xref: /freebsd/usr.bin/man/man.sh (revision dc38cf116c820df0be341ec5e359de0012b2d58a)
1#! /bin/sh
2#
3# SPDX-License-Identifier: BSD-2-Clause
4#
5#  Copyright (c) 2010 Gordon Tetlow
6#  All rights reserved.
7#
8#  Redistribution and use in source and binary forms, with or without
9#  modification, are permitted provided that the following conditions
10#  are met:
11#  1. Redistributions of source code must retain the above copyright
12#     notice, this list of conditions and the following disclaimer.
13#  2. Redistributions in binary form must reproduce the above copyright
14#     notice, this list of conditions and the following disclaimer in the
15#     documentation and/or other materials provided with the distribution.
16#
17#  THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18#  ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19#  IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20#  ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21#  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22#  DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23#  OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24#  HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25#  LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26#  OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27#  SUCH DAMAGE.
28#
29
30# Rendering a manual page is fast. Even a manual page several 100k in size
31# takes less than a CPU second. If it takes much longer, it is very likely
32# that a tool like mandoc(1) is running in an infinite loop. In this case
33# it is better to terminate it.
34ulimit -t 20
35
36# Do not ignore the exit codes of roff tools, as they may indicate a
37# problem with the page being rendered.  Note that this also causes a
38# nonzero exit when the user quits reading before reaching the end, so
39# we need to look out for and deal with that specific case.
40set -o pipefail
41
42# Usage: add_to_manpath path
43# Adds a variable to manpath while ensuring we don't have duplicates.
44# Returns true if we were able to add something. False otherwise.
45add_to_manpath() {
46	case "$manpath" in
47	*:$1)	decho "  Skipping duplicate manpath entry $1" 2 ;;
48	$1:*)	decho "  Skipping duplicate manpath entry $1" 2 ;;
49	*:$1:*)	decho "  Skipping duplicate manpath entry $1" 2 ;;
50	*)	if [ -d "$1" ]; then
51			decho "  Adding $1 to manpath"
52			manpath="$manpath:$1"
53			return 0
54		fi
55		;;
56	esac
57
58	return 1
59}
60
61# Usage: build_manlocales
62# Builds a correct MANLOCALES variable.
63build_manlocales() {
64	# If the user has set manlocales, who are we to argue.
65	if [ -n "$MANLOCALES" ]; then
66		return
67	fi
68
69	parse_configs
70
71	# Trim leading colon
72	MANLOCALES=${manlocales#:}
73
74	decho "Available manual locales: $MANLOCALES"
75}
76
77# Usage: build_mansect
78# Builds a correct MANSECT variable.
79build_mansect() {
80	# If the user has set mansect, who are we to argue.
81	if [ -n "$MANSECT" ]; then
82		return
83	fi
84
85	parse_configs
86
87	# Trim leading colon
88	MANSECT=${mansect#:}
89
90	if [ -z "$MANSECT" ]; then
91		MANSECT=$man_default_sections
92	fi
93	decho "Using manual sections: $MANSECT"
94}
95
96# Usage: build_manpath
97# Builds a correct MANPATH variable.
98build_manpath() {
99	local IFS
100
101	# If the user has set a manpath, who are we to argue.
102	if [ -n "$MANPATH" ]; then
103		case "$MANPATH" in
104		*:) PREPEND_MANPATH=${MANPATH} ;;
105		:*) APPEND_MANPATH=${MANPATH} ;;
106		*::*)
107			PREPEND_MANPATH=${MANPATH%%::*}
108			APPEND_MANPATH=${MANPATH#*::}
109			;;
110		*) return ;;
111		esac
112	fi
113
114	if [ -n "$PREPEND_MANPATH" ]; then
115		IFS=:
116		for path in $PREPEND_MANPATH; do
117			add_to_manpath "$path"
118		done
119		unset IFS
120	fi
121
122	search_path
123
124	decho "Adding default manpath entries"
125	IFS=:
126	for path in $man_default_path; do
127		add_to_manpath "$path"
128	done
129	unset IFS
130
131	parse_configs
132
133	if [ -n "$APPEND_MANPATH" ]; then
134		IFS=:
135		for path in $APPEND_MANPATH; do
136			add_to_manpath "$path"
137		done
138		unset IFS
139	fi
140	# Trim leading colon
141	MANPATH=${manpath#:}
142
143	decho "Using manual path: $MANPATH"
144}
145
146# Usage: check_cat catglob
147# Checks to see if a cat glob is available.
148check_cat() {
149	if exists "$1"; then
150		use_cat=yes
151		catpage=$found
152		setup_cattool "$catpage"
153		decho "    Found catpage \"$catpage\""
154		return 0
155	else
156		return 1
157	fi
158}
159
160# Usage: check_man manglob catglob
161# Given 2 globs, figures out if the manglob is available, if so, check to
162# see if the catglob is also available and up to date.
163check_man() {
164	if exists "$1"; then
165		# We have a match, check for a cat page
166		manpage=$found
167		setup_cattool "$manpage"
168		decho "    Found manpage \"$manpage\""
169
170		if [ -n "${use_width}" ]; then
171			# non-standard width
172			unset use_cat
173			decho "    Skipping catpage: non-standard page width"
174		elif exists "$2" && is_newer $found "$manpage"; then
175			# cat page found and is newer, use that
176			use_cat=yes
177			catpage=$found
178			setup_cattool "$catpage"
179			decho "    Using catpage \"$catpage\""
180		else
181			# no cat page or is older
182			unset use_cat
183			decho "    Skipping catpage: not found or old"
184		fi
185		return 0
186	fi
187
188	return 1
189}
190
191# Usage: decho "string" [debuglevel]
192# Echoes to stderr string prefaced with -- if high enough debuglevel.
193decho() {
194	if [ $debug -ge ${2:-1} ]; then
195		echo "-- $1" >&2
196	fi
197}
198
199# Usage: exists glob
200#
201# Returns true if glob resolves to a real file and store the first
202# found filename in the variable $found
203exists() {
204	if [ -z "$1" ]; then
205		return 1
206	fi
207
208	local IFS
209
210	# Don't accidentally inherit callers IFS (breaks perl manpages)
211	unset IFS
212
213	# Use some globbing tricks in the shell to determine if a file
214	# exists or not.
215	set +f
216	for file in "$1"*
217	do
218		if [ -r "$file" ]; then
219			found="$file"
220			set -f
221			return 0
222		fi
223	done
224	set -f
225
226	return 1
227}
228
229# Usage: find_file path section subdir pagename
230# Returns: true if something is matched and found.
231# Search the given path/section combo for a given page.
232find_file() {
233	local manroot catroot mann man0 catn cat0
234
235	manroot="$1/man$2"
236	catroot="$1/cat$2"
237	if [ -n "$3" ]; then
238		manroot="$manroot/$3"
239		catroot="$catroot/$3"
240	fi
241
242	if [ ! -d "$manroot" -a ! -d "$catroot" ]; then
243		return 1
244	fi
245	decho "  Searching directory $manroot" 2
246
247	mann="$manroot/$4.$2"
248	man0="$manroot/$4.0"
249	catn="$catroot/$4.$2"
250	cat0="$catroot/$4.0"
251
252	# This is the behavior as seen by the original man utility.
253	# Let's not change that which doesn't seem broken.
254	if check_man "$mann" "$catn"; then
255		return 0
256	elif check_man "$man0" "$cat0"; then
257		return 0
258	elif check_cat "$catn"; then
259		return 0
260	elif check_cat "$cat0"; then
261		return 0
262	fi
263
264	return 1
265}
266
267# Usage: is_newer file1 file2
268# Returns true if file1 is newer than file2 as calculated by mtime.
269is_newer() {
270	if ! [ "$1" -ot "$2" ]; then
271		decho "    mtime: $1 not older than $2" 3
272		return 0
273	else
274		decho "    mtime: $1 older than $2" 3
275		return 1
276	fi
277}
278
279# Usage: manpath_parse_args "$@"
280# Parses commandline options for manpath.
281manpath_parse_args() {
282	local cmd_arg
283
284	OPTIND=1
285	while getopts 'Ldq' cmd_arg; do
286		case "${cmd_arg}" in
287		L)	Lflag=Lflag ;;
288		d)	debug=$(( $debug + 1 )) ;;
289		q)	qflag=qflag ;;
290		*)	manpath_usage ;;
291		esac
292	done >&2
293}
294
295# Usage: manpath_usage
296# Display usage for the manpath(1) utility.
297manpath_usage() {
298	echo 'usage: manpath [-Ldq]' >&2
299	exit 1
300}
301
302# Usage: manpath_warnings
303# Display some warnings to stderr.
304manpath_warnings() {
305	if [ -n "$Lflag" -a -n "$MANLOCALES" ]; then
306		echo "(Warning: MANLOCALES environment variable set)" >&2
307	fi
308}
309
310# Usage: man_check_for_so path
311# Returns: True if able to resolve the file, false if it ended in tears.
312# Detects the presence of the .so directive and causes the file to be
313# redirected to another source file.
314man_check_for_so() {
315	local IFS line tstr
316	local counter_so=0
317	local counter_so_limit=32
318
319	unset IFS
320	if [ -n "$catpage" ]; then
321		return 0
322	fi
323
324	# We need to loop to accommodate multiple .so directives.
325	while [ $counter_so -lt $counter_so_limit ]
326	do
327		counter_so=$((counter_so + 1))
328
329		line=$($cattool "$manpage" 2>/dev/null | grep -E -m1 -v '^\.\\"[ ]*|^[ ]*$')
330		case "$line" in
331               '.so /'*) break ;; # ignore absolute path
332               '.so '*) trim "${line#.so}"
333			decho "$manpage includes $tstri level=$counter_so"
334
335			# Glob and check for the file.
336			if ! check_man "$1/$tstr" ""; then
337				decho "  Unable to find $tstr"
338				return 1
339			fi
340			;;
341		*)	break ;;
342		esac
343	done
344
345	if [ $counter_so -ge $counter_so_limit ]; then
346		decho ".so include limit of $counter_so_limit reached, stop"
347	fi
348
349	return 0
350}
351
352# Usage: man_display_page
353# Display either the manpage or catpage depending on the use_cat variable
354man_display_page() {
355	local IFS pipeline testline
356
357	# We are called with IFS set to colon. This causes really weird
358	# things to happen for the variables that have spaces in them.
359	unset IFS
360
361	# If we are supposed to use a catpage and we aren't using troff(1)
362	# just zcat the catpage and we are done.
363	if [ -z "$tflag" -a -n "$use_cat" ]; then
364		if [ -n "$wflag" ]; then
365			echo "$catpage (source: \"$manpage\")"
366			ret=0
367		else
368			if [ $debug -gt 0 ]; then
369				decho "Command: $cattool \"$catpage\" | $MANPAGER"
370				ret=0
371			else
372				$cattool "$catpage" | $MANPAGER
373				ret=$?
374			fi
375		fi
376		return
377	fi
378
379	# Okay, we are using the manpage, do we just need to output the
380	# name of the manpage?
381	if [ -n "$wflag" ]; then
382		echo "$manpage"
383		ret=0
384		return
385	fi
386
387	if [ -n "$use_width" ]; then
388		mandoc_args="-O width=${use_width}"
389	fi
390	testline="mandoc -Tlint -Wunsupp >/dev/null 2>&1"
391	if [ -n "$tflag" ]; then
392		pipeline="mandoc -Tps $mandoc_args"
393	else
394		pipeline="mandoc $mandoc_args | $MANPAGER"
395	fi
396
397	if ! $cattool "$manpage" | eval "$testline"; then
398		if which -s groff; then
399			man_display_page_groff
400		else
401			echo "This manpage needs groff(1) to be rendered" >&2
402			echo "First install groff(1): " >&2
403			echo "pkg install groff " >&2
404			ret=1
405		fi
406		return
407	fi
408
409	if [ $debug -gt 0 ]; then
410		decho "Command: $cattool \"$manpage\" | eval \"$pipeline\""
411		ret=0
412	else
413		$cattool "$manpage" | eval "$pipeline"
414		ret=$?
415	fi
416}
417
418# Usage: man_display_page_groff
419# Display the manpage using groff
420man_display_page_groff() {
421	local EQN NROFF PIC TBL TROFF REFER VGRIND
422	local IFS l nroff_dev pipeline preproc_arg tool
423
424	# So, we really do need to parse the manpage. First, figure out the
425	# device flag (-T) we have to pass to eqn(1) and groff(1). Then,
426	# setup the pipeline of commands based on the user's request.
427
428	# If the manpage is from a particular charset, we need to setup nroff
429	# to properly output for the correct device.
430	case "${manpage}" in
431	*.${man_charset}/*)
432		# I don't pretend to know this; I'm just copying from the
433		# previous version of man(1).
434		case "$man_charset" in
435		KOI8-R)		nroff_dev="koi8-r" ;;
436		ISO8859-1)	nroff_dev="latin1" ;;
437		ISO8859-15)	nroff_dev="latin1" ;;
438		UTF-8)		nroff_dev="utf8" ;;
439		*)		nroff_dev="ascii" ;;
440		esac
441
442		NROFF="$NROFF -T$nroff_dev"
443		EQN="$EQN -T$nroff_dev"
444
445		# Iff the manpage is from the locale and not just the charset,
446		# then we need to define the locale string.
447		case "${manpage}" in
448		*/${man_lang}_${man_country}.${man_charset}/*)
449			NROFF="$NROFF -dlocale=$man_lang.$man_charset"
450			;;
451		*/${man_lang}.${man_charset}/*)
452			NROFF="$NROFF -dlocale=$man_lang.$man_charset"
453			;;
454		esac
455
456		# Allow language specific calls to override the default
457		# set of utilities.
458		l=$(echo $man_lang | tr [:lower:] [:upper:])
459		for tool in EQN NROFF PIC TBL TROFF REFER VGRIND; do
460			eval "$tool=\${${tool}_$l:-\$$tool}"
461		done
462		;;
463	*)	NROFF="$NROFF -Tascii"
464		EQN="$EQN -Tascii"
465		;;
466	esac
467
468	if [ -z "$MANCOLOR" ]; then
469		NROFF="$NROFF -P-c"
470	fi
471
472	if [ -n "${use_width}" ]; then
473		NROFF="$NROFF -rLL=${use_width}n -rLT=${use_width}n"
474	fi
475
476	if [ -n "$MANROFFSEQ" ]; then
477		set -- -$MANROFFSEQ
478		OPTIND=1
479		while getopts 'egprtv' preproc_arg; do
480			case "${preproc_arg}" in
481			e)	pipeline="$pipeline | $EQN" ;;
482			g)	;; # Ignore for compatibility.
483			p)	pipeline="$pipeline | $PIC" ;;
484			r)	pipeline="$pipeline | $REFER" ;;
485			t)	pipeline="$pipeline | $TBL" ;;
486			v)	pipeline="$pipeline | $VGRIND" ;;
487			*)	usage ;;
488			esac
489		done
490		# Strip the leading " | " from the resulting pipeline.
491		pipeline="${pipeline#" | "}"
492	else
493		pipeline="$TBL"
494	fi
495
496	if [ -n "$tflag" ]; then
497		pipeline="$pipeline | $TROFF"
498	else
499		pipeline="$pipeline | $NROFF | $MANPAGER"
500	fi
501
502	if [ $debug -gt 0 ]; then
503		decho "Command: $cattool \"$manpage\" | eval \"$pipeline\""
504		ret=0
505	else
506		$cattool "$manpage" | eval "$pipeline"
507		ret=$?
508	fi
509}
510
511# Usage: man_find_and_display page
512# Search through the manpaths looking for the given page.
513man_find_and_display() {
514	local found_page has_slash locpath p path sect
515
516	# Check to see if it's a file. But only if it has a '/' in
517	# the filename or if -l was specified.
518	case "$1" in
519	*/*)	has_slash=yes
520		;;
521	esac
522	if [ -n "$has_slash" -o -n "$lflag" ]; then
523		if [ -f "$1" -a -r "$1" ]; then
524			decho "Found a usable page, displaying that"
525			if [ -z "$lflag" ]; then
526				echo "Opening a file directly is deprecated," \
527				    "use -l instead." >&2
528			fi
529			unset use_cat
530			manpage="$1"
531			setup_cattool "$manpage"
532			p=$(cd "$(dirname "$manpage")" && pwd)
533			case "$(basename "$p")" in
534				man*|cat*) p=$p/.. ;;
535				*) p=$p/../.. ;;
536			esac
537			if man_check_for_so "$p"; then
538				found_page=yes
539				man_display_page
540			fi
541			return
542		elif [ -n "$lflag" ]; then
543			echo "Cannot read $1" >&2
544			ret=1
545			return
546		fi
547	fi
548
549	IFS=:
550	for sect in $MANSECT; do
551		decho "Searching section $sect" 2
552		for path in $MANPATH; do
553			for locpath in $locpaths; do
554				p=$path/$locpath
555				p=${p%/.} # Rid ourselves of the trailing /.
556
557				# Check if there is a MACHINE specific manpath.
558				if find_file $p $sect $MACHINE "$1"; then
559					if man_check_for_so $p; then
560						found_page=yes
561						man_display_page
562						if [ -n "$aflag" ]; then
563							continue 2
564						else
565							return
566						fi
567					fi
568				fi
569
570				# Check if there is a MACHINE_ARCH
571				# specific manpath.
572				if find_file $p $sect $MACHINE_ARCH "$1"; then
573					if man_check_for_so $p; then
574						found_page=yes
575						man_display_page
576						if [ -n "$aflag" ]; then
577							continue 2
578						else
579							return
580						fi
581					fi
582				fi
583
584				# Check plain old manpath.
585				if find_file $p $sect '' "$1"; then
586					if man_check_for_so $p; then
587						found_page=yes
588						man_display_page
589						if [ -n "$aflag" ]; then
590							continue 2
591						else
592							return
593						fi
594					fi
595				fi
596			done
597		done
598	done
599	unset IFS
600
601	# Nothing? Well, we are done then.
602	if [ -z "$found_page" ]; then
603		echo "No manual entry for \"$1\"" >&2
604		ret=1
605		return
606	fi
607}
608
609# Usage: man_parse_opts "$@"
610# Parses commandline options for man.
611man_parse_opts() {
612	local cmd_arg
613
614	OPTIND=1
615	while getopts 'K:M:P:S:adfhklm:op:tw' cmd_arg; do
616		case "${cmd_arg}" in
617		K)	Kflag=Kflag
618			REGEXP=$OPTARG ;;
619		M)	MANPATH=$OPTARG ;;
620		P)	MANPAGER=$OPTARG ;;
621		S)	MANSECT=$OPTARG ;;
622		a)	aflag=aflag ;;
623		d)	debug=$(( $debug + 1 )) ;;
624		f)	fflag=fflag ;;
625		h)	man_usage 0 ;;
626		k)	kflag=kflag ;;
627		l)	lflag=lflag ;;
628		m)	mflag=$OPTARG ;;
629		o)	oflag=oflag ;;
630		p)	MANROFFSEQ=$OPTARG ;;
631		t)	tflag=tflag ;;
632		w)	wflag=wflag ;;
633		*)	man_usage ;;
634		esac
635	done >&2
636
637	shift $(( $OPTIND - 1 ))
638
639	# Check the args for incompatible options.
640	case "${Kflag}${fflag}${kflag}${lflag}${tflag}${wflag}" in
641	Kflagfflag*)	echo "Incompatible options: -K and -f"; man_usage ;;
642	Kflag*kflag*)	echo "Incompatible options: -K and -k"; man_usage ;;
643	Kflag*lflag*)	echo "Incompatible options: -K and -l"; man_usage ;;
644	Kflag*tflag)	echo "Incompatible options: -K and -t"; man_usage ;;
645	fflagkflag*)	echo "Incompatible options: -f and -k"; man_usage ;;
646	fflag*lflag*)	echo "Incompatible options: -f and -l"; man_usage ;;
647	fflag*tflag*)	echo "Incompatible options: -f and -t"; man_usage ;;
648	fflag*wflag)	echo "Incompatible options: -f and -w"; man_usage ;;
649	*kflaglflag*)	echo "Incompatible options: -k and -l"; man_usage ;;
650	*kflag*tflag*)	echo "Incompatible options: -k and -t"; man_usage ;;
651	*kflag*wflag)	echo "Incompatible options: -k and -w"; man_usage ;;
652	*lflag*wflag)	echo "Incompatible options: -l and -w"; man_usage ;;
653	*tflagwflag)	echo "Incompatible options: -t and -w"; man_usage ;;
654	esac
655
656	# Short circuit for whatis(1) and apropos(1)
657	if [ -n "$fflag" ]; then
658		do_whatis "$@"
659		exit
660	fi
661
662	if [ -n "$kflag" ]; then
663		do_apropos "$@"
664		exit
665	fi
666}
667
668# Usage: man_setup
669# Setup various trivial but essential variables.
670man_setup() {
671	# Setup machine and architecture variables.
672	if [ -n "$mflag" ]; then
673		MACHINE_ARCH=${mflag%%:*}
674		MACHINE=${mflag##*:}
675	fi
676	if [ -z "$MACHINE_ARCH" ]; then
677		MACHINE_ARCH=$($SYSCTL -n hw.machine_arch)
678	fi
679	if [ -z "$MACHINE" ]; then
680		MACHINE=$($SYSCTL -n hw.machine)
681	fi
682	decho "Using architecture: $MACHINE_ARCH:$MACHINE"
683
684	setup_pager
685	build_manpath
686	build_mansect
687	man_setup_locale
688	man_setup_width
689}
690
691# Usage: man_setup_width
692# Set up page width.
693man_setup_width() {
694	local sizes
695
696	unset use_width
697	case "$MANWIDTH" in
698	[0-9]*)
699		if [ "$MANWIDTH" -gt 0 2>/dev/null ]; then
700			use_width=$MANWIDTH
701		fi
702		;;
703	[Tt][Tt][Yy])
704		if { sizes=$($STTY size 0>&3 2>/dev/null); } 3>&1; then
705			set -- $sizes
706			if [ $2 -gt 80 ]; then
707				use_width=$(($2-2))
708			fi
709		fi
710		;;
711	esac
712	if [ -n "$use_width" ]; then
713		decho "Using non-standard page width: ${use_width}"
714	else
715		decho 'Using standard page width'
716	fi
717}
718
719# Usage: man_setup_locale
720# Setup necessary locale variables.
721man_setup_locale() {
722	local lang_cc
723	local locstr
724
725	locpaths='.'
726	man_charset='US-ASCII'
727
728	# Setup locale information.
729	if [ -n "$oflag" ]; then
730		decho 'Using non-localized manpages'
731	else
732		# Use the locale tool to give us proper locale information
733		eval $( $LOCALE )
734
735		if [ -n "$LANG" ]; then
736			locstr=$LANG
737		else
738			locstr=$LC_CTYPE
739		fi
740
741		case "$locstr" in
742		C)		;;
743		C.UTF-8)	;;
744		POSIX)		;;
745		[a-z][a-z]_[A-Z][A-Z]\.*)
746				lang_cc="${locstr%.*}"
747				man_lang="${locstr%_*}"
748				man_country="${lang_cc#*_}"
749				man_charset="${locstr#*.}"
750				locpaths="$locstr"
751				locpaths="$locpaths:$man_lang.$man_charset"
752				if [ "$man_lang" != "en" ]; then
753					locpaths="$locpaths:en.$man_charset"
754				fi
755				locpaths="$locpaths:."
756				;;
757		*)		echo 'Unknown locale, assuming C' >&2
758				;;
759		esac
760	fi
761
762	decho "Using locale paths: $locpaths"
763}
764
765# Usage: man_usage [exitcode]
766# Display usage for the man utility.
767man_usage() {
768	echo 'Usage:'
769	echo ' man [-adhlo] [-t | -w] [-M manpath] [-P pager] [-S mansect]'
770	echo '     [-m arch[:machine]] [-p [eprtv]] [mansect] page [...]'
771	echo ' man -K | -f | -k expression [...] -- Search manual pages'
772
773	# When exit'ing with -h, it's not an error.
774	exit ${1:-1}
775}
776
777# Usage: parse_configs
778# Reads the end-user adjustable config files.
779parse_configs() {
780	local IFS file files
781
782	if [ -n "$parsed_configs" ]; then
783		return
784	fi
785
786	unset IFS
787
788	# Read the global config first in case the user wants
789	# to override config_local.
790	if [ -r "$config_global" ]; then
791		parse_file "$config_global"
792	fi
793
794	# Glob the list of files to parse.
795	set +f
796	files=$(echo $config_local)
797	set -f
798
799	for file in $files; do
800		if [ -r "$file" ]; then
801			parse_file "$file"
802		fi
803	done
804
805	parsed_configs='yes'
806}
807
808# Usage: parse_file file
809# Reads the specified config files.
810parse_file() {
811	local file line tstr var
812
813	file="$1"
814	decho "Parsing config file: $file"
815	while read line; do
816		decho "  $line" 2
817		case "$line" in
818		\#*)		decho "    Comment" 3
819				;;
820		MANPATH*)	decho "    MANPATH" 3
821				trim "${line#MANPATH}"
822				add_to_manpath "$tstr"
823				;;
824		MANLOCALE*)	decho "    MANLOCALE" 3
825				trim "${line#MANLOCALE}"
826				manlocales="$manlocales:$tstr"
827				;;
828		MANCONFIG*)	decho "    MANCONFIG" 3
829				trim "${line#MANCONFIG}"
830				config_local="$tstr"
831				;;
832		MANSECT*)	decho "    MANSECT" 3
833				trim "${line#MANSECT}"
834				mansect="$mansect:$tstr"
835				;;
836		# Set variables in the form of FOO_BAR
837		*_*[\ \	]*)	var="${line%%[\ \	]*}"
838				trim "${line#$var}"
839				eval "$var=\"$tstr\""
840				decho "    Parsed $var" 3
841				;;
842		esac
843	done < "$file"
844}
845
846# Usage: search_path
847# Traverse $PATH looking for manpaths.
848search_path() {
849	local IFS p path
850
851	decho "Searching PATH for man directories"
852
853	IFS=:
854	for path in $PATH; do
855		if add_to_manpath "$path/man"; then
856			:
857		elif add_to_manpath "$path/MAN"; then
858			:
859		else
860			case "$path" in
861			*/bin)	p="${path%/bin}/share/man"
862				add_to_manpath "$p"
863				p="${path%/bin}/man"
864				add_to_manpath "$p"
865				;;
866			esac
867		fi
868	done
869	unset IFS
870
871	if [ -z "$manpath" ]; then
872		decho '  Unable to find any manpaths, using default'
873		manpath=$man_default_path
874	fi
875}
876
877# Usage: search_whatis cmd [arglist]
878# Do the heavy lifting for apropos/whatis
879search_whatis() {
880	local IFS bad cmd f good key keywords loc opt out path rval wlist
881
882	cmd="$1"
883	shift
884
885	whatis_parse_args "$@"
886
887	build_manpath
888	build_manlocales
889	setup_pager
890
891	if [ "$cmd" = "whatis" ]; then
892		opt="-w"
893	fi
894
895	f='whatis'
896
897	IFS=:
898	for path in $MANPATH; do
899		if [ \! -d "$path" ]; then
900			decho "Skipping non-existent path: $path" 2
901			continue
902		fi
903
904		if [ -f "$path/$f" -a -r "$path/$f" ]; then
905			decho "Found whatis: $path/$f"
906			wlist="$wlist $path/$f"
907		fi
908
909		for loc in $MANLOCALES; do
910			if [ -f "$path/$loc/$f" -a -r "$path/$loc/$f" ]; then
911				decho "Found whatis: $path/$loc/$f"
912				wlist="$wlist $path/$loc/$f"
913			fi
914		done
915	done
916	unset IFS
917
918	if [ -z "$wlist" ]; then
919		echo "$cmd: no whatis databases in $MANPATH" >&2
920		exit 1
921	fi
922
923	rval=0
924	for key in $keywords; do
925		out=$(grep -Ehi $opt -- "$key" $wlist)
926		if [ -n "$out" ]; then
927			good="$good\\n$out"
928		else
929			bad="$bad\\n$key: nothing appropriate"
930			rval=1
931		fi
932	done
933
934	# Strip leading carriage return.
935	good=${good#\\n}
936	bad=${bad#\\n}
937
938	if [ -n "$good" ]; then
939		printf '%b\n' "$good" | $MANPAGER
940	fi
941
942	if [ -n "$bad" ]; then
943		printf '%b\n' "$bad" >&2
944	fi
945
946	exit $rval
947}
948
949# Usage: setup_cattool page
950# Finds an appropriate decompressor based on extension
951setup_cattool() {
952	case "$1" in
953	*.bz)	cattool='/usr/bin/bzcat' ;;
954	*.bz2)	cattool='/usr/bin/bzcat' ;;
955	*.gz)	cattool='/usr/bin/gzcat' ;;
956	*.lzma)	cattool='/usr/bin/lzcat' ;;
957	*.xz)	cattool='/usr/bin/xzcat' ;;
958	*.zst)	cattool='/usr/bin/zstdcat' ;;
959	*)	cattool='/usr/bin/zcat -f' ;;
960	esac
961}
962
963# Usage: setup_pager
964# Correctly sets $MANPAGER
965setup_pager() {
966	# Setup pager.
967	if [ -z "$MANPAGER" ]; then
968		if [ -n "$MANCOLOR" ]; then
969			MANPAGER="less -sR"
970		else
971			if [ -n "$PAGER" ]; then
972				MANPAGER="$PAGER"
973			else
974				MANPAGER="less -s"
975			fi
976		fi
977	fi
978	decho "Using pager: $MANPAGER"
979}
980
981# Usage: trim string
982# Trims whitespace from beginning and end of a variable
983trim() {
984	tstr=$1
985	while true; do
986		case "$tstr" in
987		[\ \	]*)	tstr="${tstr##[\ \	]}" ;;
988		*[\ \	])	tstr="${tstr%%[\ \	]}" ;;
989		*)		break ;;
990		esac
991	done
992}
993
994# Usage: whatis_parse_args "$@"
995# Parse commandline args for whatis and apropos.
996whatis_parse_args() {
997	local cmd_arg
998	OPTIND=1
999	while getopts 'd' cmd_arg; do
1000		case "${cmd_arg}" in
1001		d)	debug=$(( $debug + 1 )) ;;
1002		*)	whatis_usage ;;
1003		esac
1004	done >&2
1005
1006	shift $(( $OPTIND - 1 ))
1007
1008	keywords="$*"
1009}
1010
1011# Usage: whatis_usage
1012# Display usage for the whatis/apropos utility.
1013whatis_usage() {
1014	echo "usage: $cmd [-d] keyword [...]"
1015	exit 1
1016}
1017
1018
1019
1020# Supported commands
1021do_apropos() {
1022	[ $(stat -f %i /usr/bin/man) -ne $(stat -f %i /usr/bin/apropos) ] && \
1023		exec apropos "$@"
1024	search_whatis apropos "$@"
1025}
1026
1027# Usage: do_full_search reg_exp
1028# Do a full search of the regular expression passed
1029# as parameter in all man pages
1030do_full_search() {
1031	local gflags re
1032	re=${1}
1033
1034	# Build grep(1) flags
1035	gflags="-H"
1036
1037	# wflag implies -l for grep(1)
1038	if [ -n "$wflag" ]; then
1039		gflags="${gflags} -l"
1040	fi
1041
1042	gflags="${gflags} --label"
1043
1044	set +f
1045	for mpath in $(echo "${MANPATH}" | tr : '[:blank:]'); do
1046		for section in $(echo "${MANSECT}" | tr : '[:blank:]'); do
1047			for manfile in ${mpath}/man${section}/*.${section}*; do
1048				mandoc "${manfile}" 2>/dev/null |
1049					grep -E ${gflags} "${manfile}" -e "${re}"
1050			done
1051		done
1052	done
1053	set -f
1054}
1055
1056do_man() {
1057	local IFS
1058
1059	man_parse_opts "$@"
1060	man_setup
1061
1062	shift $(( $OPTIND - 1 ))
1063	IFS=:
1064	for sect in $MANSECT; do
1065		if [ "$sect" = "$1" ]; then
1066			decho "Detected manual section as first arg: $1"
1067			MANSECT="$1"
1068			shift
1069			break
1070		fi
1071	done
1072	unset IFS
1073	pages="$*"
1074
1075	if [ -z "$pages" -a -z "${Kflag}" ]; then
1076		echo 'What manual page do you want?' >&2
1077		exit 1
1078	fi
1079
1080	if [ ! -z "${Kflag}" ]; then
1081		# Short circuit because -K flag does a sufficiently
1082		# different thing like not showing the man page at all
1083		do_full_search "${REGEXP}"
1084	fi
1085
1086	for page in "$@"; do
1087		decho "Searching for \"$page\""
1088		man_find_and_display "$page"
1089	done
1090
1091	# The user will very commonly quit reading the page before
1092	# reaching the bottom.  Depending on the length of the page
1093	# and the pager's buffer size, this may result in a SIGPIPE.
1094	# This is normal, so convert that exit code to zero.
1095	if [ ${ret:-0} -gt 128 ]; then
1096		if [ "$(kill -l "${ret}")" = "PIPE" ]; then
1097			ret=0
1098		fi
1099	fi
1100
1101	exit ${ret:-0}
1102}
1103
1104do_manpath() {
1105	manpath_parse_args "$@"
1106	if [ -z "$qflag" ]; then
1107		manpath_warnings
1108	fi
1109	if [ -n "$Lflag" ]; then
1110		build_manlocales
1111		echo $MANLOCALES
1112	else
1113		build_manpath
1114		echo $MANPATH
1115	fi
1116	exit 0
1117}
1118
1119do_whatis() {
1120	[ $(stat -f %i /usr/bin/man) -ne $(stat -f %i /usr/bin/whatis) ] && \
1121		exec whatis "$@"
1122	search_whatis whatis "$@"
1123}
1124
1125# User's PATH setting decides on the groff-suite to pick up.
1126EQN=eqn
1127NROFF='groff -S -P-h -Wall -mtty-char -mandoc'
1128PIC=pic
1129REFER=refer
1130TBL=tbl
1131TROFF='groff -S -mandoc'
1132VGRIND=vgrind
1133
1134LOCALE=/usr/bin/locale
1135STTY=/bin/stty
1136SYSCTL=/sbin/sysctl
1137
1138debug=0
1139man_default_sections='1:8:2:3:3lua:n:4:5:6:7:9:l'
1140man_default_path='/usr/share/man:/usr/share/openssl/man:/usr/local/share/man:/usr/local/man'
1141cattool='/usr/bin/zcat -f'
1142
1143config_global='/etc/man.conf'
1144
1145# This can be overridden via a setting in /etc/man.conf.
1146config_local='/usr/local/etc/man.d/*.conf'
1147
1148# Set noglobbing for now. I don't want spurious globbing.
1149set -f
1150
1151case "$0" in
1152*apropos)	do_apropos "$@" ;;
1153*manpath)	do_manpath "$@" ;;
1154*whatis)	do_whatis "$@" ;;
1155*)		do_man "$@" ;;
1156esac
1157