xref: /freebsd/usr.sbin/etcupdate/etcupdate.sh (revision 4f7336a93cb84a0633ca9aa715e474625b4adce5)
1#!/bin/sh
2#
3# SPDX-License-Identifier: BSD-2-Clause
4#
5# Copyright (c) 2010-2013 Hudson River Trading LLC
6# Written by: John H. Baldwin <jhb@FreeBSD.org>
7# All rights reserved.
8#
9# Redistribution and use in source and binary forms, with or without
10# modification, are permitted provided that the following conditions
11# are met:
12# 1. Redistributions of source code must retain the above copyright
13#    notice, this list of conditions and the following disclaimer.
14# 2. Redistributions in binary form must reproduce the above copyright
15#    notice, this list of conditions and the following disclaimer in the
16#    documentation and/or other materials provided with the distribution.
17#
18# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21# ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28# SUCH DAMAGE.
29#
30
31# This is a tool to manage updating files that are not updated as part
32# of 'make installworld' such as files in /etc.  Unlike other tools,
33# this one is specifically tailored to assisting with mass upgrades.
34# To that end it does not require user intervention while running.
35#
36# Theory of operation:
37#
38# The most reliable way to update changes to files that have local
39# modifications is to perform a three-way merge between the original
40# unmodified file, the new version of the file, and the modified file.
41# This requires having all three versions of the file available when
42# performing an update.
43#
44# To that end, etcupdate uses a strategy where the current unmodified
45# tree is kept in WORKDIR/current and the previous unmodified tree is
46# kept in WORKDIR/old.  When performing a merge, a new tree is built
47# if needed and then the changes are merged into DESTDIR.  Any files
48# with unresolved conflicts after the merge are left in a tree rooted
49# at WORKDIR/conflicts.
50#
51# To provide extra flexibility, etcupdate can also build tarballs of
52# root trees that can later be used.  It can also use a tarball as the
53# source of a new tree instead of building it from /usr/src.
54
55# Global settings.  These can be adjusted by config files and in some
56# cases by command line options.
57
58# TODO:
59# - automatable conflict resolution
60
61usage()
62{
63	cat <<EOF
64usage: etcupdate [-npBFN] [-d workdir] [-r | -s source | -t tarball]
65                 [-A patterns] [-D destdir] [-I patterns] [-L logfile]
66                 [-M options] [-m make]
67       etcupdate build [-BN] [-d workdir] [-s source] [-L logfile] [-M options]
68                 [-m make] <tarball>
69       etcupdate diff [-d workdir] [-D destdir] [-I patterns] [-L logfile]
70       etcupdate extract [-BN] [-d workdir] [-s source | -t tarball]
71                 [-D destdir] [-L logfile] [-M options] [-m make]
72       etcupdate resolve [-p] [-d workdir] [-D destdir] [-L logfile]
73       etcupdate revert [-d workdir] [-D destdir] [-L logfile] file ...
74       etcupdate status [-d workdir] [-D destdir]
75EOF
76	exit 1
77}
78
79# Used to write a message prepended with '>>>' to the logfile.
80log()
81{
82	echo ">>>" "$@" >&3
83}
84
85# Used for assertion conditions that should never happen.
86panic()
87{
88	echo "PANIC:" "$@"
89	exit 10
90}
91
92# Used to write a warning message.  These are saved to the WARNINGS
93# file with "  " prepended.
94warn()
95{
96	echo -n "  " >> $WARNINGS
97	echo "$@" >> $WARNINGS
98}
99
100# Output a horizontal rule using the passed-in character.  Matches the
101# length used for Index lines in CVS and SVN diffs.
102#
103# $1 - character
104rule()
105{
106	jot -b "$1" -s "" 67
107}
108
109# Output a text description of a specified file's type.
110#
111# $1 - file pathname.
112file_type()
113{
114	stat -f "%HT" $1 | tr "[:upper:]" "[:lower:]"
115}
116
117# Returns true (0) if a file exists
118#
119# $1 - file pathname.
120exists()
121{
122	[ -e $1 -o -L $1 ]
123}
124
125# Returns true (0) if a file should be ignored, false otherwise.
126#
127# $1 - file pathname
128ignore()
129{
130	local pattern -
131
132	set -o noglob
133	for pattern in $IGNORE_FILES; do
134		set +o noglob
135		case $1 in
136			$pattern)
137				return 0
138				;;
139		esac
140		set -o noglob
141	done
142
143	# Ignore /.cshrc and /.profile if they are hardlinked to the
144	# same file in /root.  This ensures we only compare those
145	# files once in that case.
146	case $1 in
147		/.cshrc|/.profile)
148			if [ ${DESTDIR}$1 -ef ${DESTDIR}/root$1 ]; then
149				return 0
150			fi
151			;;
152		*)
153			;;
154	esac
155
156	return 1
157}
158
159# Returns true (0) if the new version of a file should always be
160# installed rather than attempting to do a merge.
161#
162# $1 - file pathname
163always_install()
164{
165	local pattern -
166
167	set -o noglob
168	for pattern in $ALWAYS_INSTALL; do
169		set +o noglob
170		case $1 in
171			$pattern)
172				return 0
173				;;
174		esac
175		set -o noglob
176	done
177
178	return 1
179}
180
181# Build a new tree.  This runs inside a subshell to trap SIGINT.
182#
183# $1 - directory to store new tree in
184build_tree()
185(
186	local destdir dir file make autogenfiles metatmp
187
188	make="$MAKE_CMD $MAKE_OPTIONS -DNO_FILEMON"
189
190	if [ -n "$noroot" ]; then
191		make="$make -DNO_ROOT"
192		metatmp=`mktemp $WORKDIR/etcupdate-XXXXXXX`
193		: > $metatmp
194		trap "rm -f $metatmp; trap '' EXIT; return 1" INT
195		trap "rm -f $metatmp" EXIT
196	else
197		metatmp="/dev/null"
198		trap "return 1" INT
199	fi
200
201	log "Building tree at $1 with $make"
202
203	exec >&3 2>&1
204
205	mkdir -p $1/usr/obj
206	destdir=`realpath $1`
207
208	if [ -n "$preworld" ]; then
209		# Build a limited tree that only contains files that are
210		# crucial to installworld.
211		for file in $PREWORLD_FILES; do
212			name=$(basename $file)
213			mkdir -p $1/etc || return 1
214			cp -p $SRCDIR/$file $1/etc/$name || return 1
215		done
216	else
217		(
218			cd $SRCDIR || exit 1
219			if ! [ -n "$nobuild" ]; then
220				export MAKEOBJDIRPREFIX=$destdir/usr/obj
221				if [ -n "$($make -V.ALLTARGETS:Mbuildetc)" ]; then
222					$make buildetc || exit 1
223				else
224					$make _obj SUBDIR_OVERRIDE=etc || exit 1
225					$make everything SUBDIR_OVERRIDE=etc || exit 1
226				fi
227			fi
228			if [ -n "$($make -V.ALLTARGETS:Minstalletc)" ]; then
229				$make DESTDIR=$destdir installetc || exit 1
230			else
231				$make DESTDIR=$destdir distrib-dirs || exit 1
232				$make DESTDIR=$destdir distribution || exit 1
233			fi
234		) || return 1
235	fi
236	chflags -R noschg $1 || return 1
237	rm -rf $1/usr/obj || return 1
238
239	# Purge auto-generated files.  Only the source files need to
240	# be updated after which these files are regenerated.
241	autogenfiles="./etc/*.db ./etc/passwd ./var/db/services.db"
242	(cd $1 && printf '%s\n' $autogenfiles >> $metatmp && \
243	    rm -f $autogenfiles) || return 1
244
245	# Trim empty directories.
246	(cd $1 && find . -depth -type d -empty -delete -print >> $metatmp) || \
247	    return 1
248
249	if [ -n "$noroot" ]; then
250		# Rewrite the METALOG to exclude the files (and directories)
251		# removed above. $metatmp contains the list of files to delete,
252		# and we append #METALOG# as a delimiter followed by the
253		# original METALOG. This lets us scan through $metatmp in awk
254		# building up a table of names to delete until we reach the
255		# delimiter, then emit all the entries of the original METALOG
256		# after it that aren't in that table. We also exclude ./usr/obj
257		# and its children explicitly for simplicity rather than
258		# building up that list (and in practice only ./usr/obj itself
259		# will be in the METALOG since nothing is installed there).
260		echo '#METALOG#' >> $metatmp || return 1
261		cat $1/METALOG >> $metatmp || return 1
262		awk '/^#METALOG#$/ { metalog = 1; next }
263		    { f=$1; gsub(/\/\/+/, "/", f) }
264		    !metalog { rm[f] = 1; next }
265		    !rm[f] && f !~ /^\.\/usr\/obj(\/|$)/ { print }' \
266		    $metatmp > $1/METALOG || return 1
267	fi
268
269	return 0
270)
271
272# Generate a new tree.  If tarball is set, then the tree is
273# extracted from the tarball.  Otherwise the tree is built from a
274# source tree.
275#
276# $1 - directory to store new tree in
277extract_tree()
278{
279	local files
280
281	# If we have a tarball, extract that into the new directory.
282	if [ -n "$tarball" ]; then
283		files=
284		if [ -n "$preworld" ]; then
285			files="$PREWORLD_FILES"
286		fi
287		if ! (mkdir -p $1 && tar xf $tarball -C $1 $files) \
288		    >&3 2>&1; then
289			echo "Failed to extract new tree."
290			remove_tree $1
291			exit 1
292		fi
293	else
294		if ! build_tree $1; then
295			echo "Failed to build new tree."
296			remove_tree $1
297			exit 1
298		fi
299	fi
300}
301
302# Forcefully remove a tree.  Returns true (0) if the operation succeeds.
303#
304# $1 - path to tree
305remove_tree()
306{
307
308	rm -rf $1 >&3 2>&1
309	if [ -e $1 ]; then
310		chflags -R noschg $1 >&3 2>&1
311		rm -rf $1 >&3 2>&1
312	fi
313	[ ! -e $1 ]
314}
315
316# Return values for compare()
317COMPARE_EQUAL=0
318COMPARE_ONLYFIRST=1
319COMPARE_ONLYSECOND=2
320COMPARE_DIFFTYPE=3
321COMPARE_DIFFLINKS=4
322COMPARE_DIFFFILES=5
323
324# Compare two files/directories/symlinks.  Note that this does not
325# recurse into subdirectories.  Instead, if two nodes are both
326# directories, they are assumed to be equivalent.
327#
328# Returns true (0) if the nodes are identical.  If only one of the two
329# nodes are present, return one of the COMPARE_ONLY* constants.  If
330# the nodes are different, return one of the COMPARE_DIFF* constants
331# to indicate the type of difference.
332#
333# $1 - first node
334# $2 - second node
335compare()
336{
337	local first second
338
339	# If the first node doesn't exist, then check for the second
340	# node.  Note that -e will fail for a symbolic link that
341	# points to a missing target.
342	if ! exists $1; then
343		if exists $2; then
344			return $COMPARE_ONLYSECOND
345		else
346			return $COMPARE_EQUAL
347		fi
348	elif ! exists $2; then
349		return $COMPARE_ONLYFIRST
350	fi
351
352	# If the two nodes are different file types fail.
353	first=`stat -f "%Hp" $1`
354	second=`stat -f "%Hp" $2`
355	if [ "$first" != "$second" ]; then
356		return $COMPARE_DIFFTYPE
357	fi
358
359	# If both are symlinks, compare the link values.
360	if [ -L $1 ]; then
361		first=`readlink $1`
362		second=`readlink $2`
363		if [ "$first" = "$second" ]; then
364			return $COMPARE_EQUAL
365		else
366			return $COMPARE_DIFFLINKS
367		fi
368	fi
369
370	# If both are files, compare the file contents.
371	if [ -f $1 ]; then
372		if cmp -s $1 $2; then
373			return $COMPARE_EQUAL
374		else
375			return $COMPARE_DIFFFILES
376		fi
377	fi
378
379	# As long as the two nodes are the same type of file, consider
380	# them equivalent.
381	return $COMPARE_EQUAL
382}
383
384# Returns true (0) if the only difference between two regular files is a
385# change in the FreeBSD ID string.
386#
387# $1 - path of first file
388# $2 - path of second file
389fbsdid_only()
390{
391
392	diff -qI '\$FreeBSD.*\$' $1 $2 >/dev/null 2>&1
393}
394
395# This is a wrapper around compare that will return COMPARE_EQUAL if
396# the only difference between two regular files is a change in the
397# FreeBSD ID string.  It only makes this adjustment if the -F flag has
398# been specified.
399#
400# $1 - first node
401# $2 - second node
402compare_fbsdid()
403{
404	local cmp
405
406	compare $1 $2
407	cmp=$?
408
409	if [ -n "$FREEBSD_ID" -a "$cmp" -eq $COMPARE_DIFFFILES ] && \
410	    fbsdid_only $1 $2; then
411		return $COMPARE_EQUAL
412	fi
413
414	return $cmp
415}
416
417# Returns true (0) if a directory is empty.
418#
419# $1 - pathname of the directory to check
420empty_dir()
421{
422	local contents
423
424	contents=`ls -A $1`
425	[ -z "$contents" ]
426}
427
428# Returns true (0) if one directories contents are a subset of the
429# other.  This will recurse to handle subdirectories and compares
430# individual files in the trees.  Its purpose is to quiet spurious
431# directory warnings for dryrun invocations.
432#
433# $1 - first directory (sub)
434# $2 - second directory (super)
435dir_subset()
436{
437	local contents file
438
439	if ! [ -d $1 -a -d $2 ]; then
440		return 1
441	fi
442
443	# Ignore files that are present in the second directory but not
444	# in the first.
445	contents=`ls -A $1`
446	for file in $contents; do
447		if ! compare $1/$file $2/$file; then
448			return 1
449		fi
450
451		if [ -d $1/$file ]; then
452			if ! dir_subset $1/$file $2/$file; then
453				return 1
454			fi
455		fi
456	done
457	return 0
458}
459
460# Returns true (0) if a directory in the destination tree is empty.
461# If this is a dryrun, then this returns true as long as the contents
462# of the directory are a subset of the contents in the old tree
463# (meaning that the directory would be empty in a non-dryrun when this
464# was invoked) to quiet spurious warnings.
465#
466# $1 - pathname of the directory to check relative to DESTDIR.
467empty_destdir()
468{
469
470	if [ -n "$dryrun" ]; then
471		dir_subset $DESTDIR/$1 $OLDTREE/$1
472		return
473	fi
474
475	empty_dir $DESTDIR/$1
476}
477
478# Output a diff of two directory entries with the same relative name
479# in different trees.  Note that as with compare(), this does not
480# recurse into subdirectories.  If the nodes are identical, nothing is
481# output.
482#
483# $1 - first tree
484# $2 - second tree
485# $3 - node name
486# $4 - label for first tree
487# $5 - label for second tree
488diffnode()
489{
490	local first second file old new diffargs
491
492	if [ -n "$FREEBSD_ID" ]; then
493		diffargs="-I \\\$FreeBSD.*\\\$"
494	else
495		diffargs=""
496	fi
497
498	compare_fbsdid $1/$3 $2/$3
499	case $? in
500		$COMPARE_EQUAL)
501			;;
502		$COMPARE_ONLYFIRST)
503			echo
504			echo "Removed: $3"
505			echo
506			;;
507		$COMPARE_ONLYSECOND)
508			echo
509			echo "Added: $3"
510			echo
511			;;
512		$COMPARE_DIFFTYPE)
513			first=`file_type $1/$3`
514			second=`file_type $2/$3`
515			echo
516			echo "Node changed from a $first to a $second: $3"
517			echo
518			;;
519		$COMPARE_DIFFLINKS)
520			first=`readlink $1/$file`
521			second=`readlink $2/$file`
522			echo
523			echo "Link changed: $file"
524			rule "="
525			echo "-$first"
526			echo "+$second"
527			echo
528			;;
529		$COMPARE_DIFFFILES)
530			echo "Index: $3"
531			rule "="
532			diff -u $diffargs -L "$3 ($4)" $1/$3 -L "$3 ($5)" $2/$3
533			;;
534	esac
535}
536
537# Run one-off commands after an update has completed.  These commands
538# are not tied to a specific file, so they cannot be handled by
539# post_install_file().
540post_update()
541{
542	local args
543
544	# None of these commands should be run for a pre-world update.
545	if [ -n "$preworld" ]; then
546		return
547	fi
548
549	# If /etc/localtime exists and is not a symlink and /var/db/zoneinfo
550	# exists, run tzsetup -r to refresh /etc/localtime.
551	if [ -f ${DESTDIR}/etc/localtime -a \
552	    ! -L ${DESTDIR}/etc/localtime ]; then
553		if [ -f ${DESTDIR}/var/db/zoneinfo ]; then
554			if [ -n "${DESTDIR}" ]; then
555				args="-C ${DESTDIR}"
556			else
557				args=""
558			fi
559			log "tzsetup -r ${args}"
560			if [ -z "$dryrun" ]; then
561				tzsetup -r ${args} >&3 2>&1
562			fi
563		else
564			warn "Needs update: /etc/localtime (required" \
565			    "manual update via tzsetup(8))"
566		fi
567	fi
568}
569
570# Create missing parent directories of a node in a target tree
571# preserving the owner, group, and permissions from a specified
572# template tree.
573#
574# $1 - template tree
575# $2 - target tree
576# $3 - pathname of the node (relative to both trees)
577install_dirs()
578{
579	local args dir
580
581	dir=`dirname $3`
582
583	# Nothing to do if the parent directory exists.  This also
584	# catches the degenerate cases when the path is just a simple
585	# filename.
586	if [ -d ${2}$dir ]; then
587		return 0
588	fi
589
590	# If non-directory file exists with the desired directory
591	# name, then fail.
592	if exists ${2}$dir; then
593		# If this is a dryrun and we are installing the
594		# directory in the DESTDIR and the file in the DESTDIR
595		# matches the file in the old tree, then fake success
596		# to quiet spurious warnings.
597		if [ -n "$dryrun" -a "$2" = "$DESTDIR" ]; then
598			if compare $OLDTREE/$dir $DESTDIR/$dir; then
599				return 0
600			fi
601		fi
602
603		args=`file_type ${2}$dir`
604		warn "Directory mismatch: ${2}$dir ($args)"
605		return 1
606	fi
607
608	# Ensure the parent directory of the directory is present
609	# first.
610	if ! install_dirs $1 "$2" $dir; then
611		return 1
612	fi
613
614	# Format attributes from template directory as install(1)
615	# arguments.
616	args=`stat -f "-o %Su -g %Sg -m %0Mp%0Lp" $1/$dir`
617
618	log "install -d $args ${2}$dir"
619	if [ -z "$dryrun" ]; then
620		install -d $args ${2}$dir >&3 2>&1
621	fi
622	return 0
623}
624
625# Perform post-install fixups for a file.  This largely consists of
626# regenerating any files that depend on the newly installed file.
627#
628# $1 - pathname of the updated file (relative to DESTDIR)
629post_install_file()
630{
631	case $1 in
632		/etc/mail/aliases)
633			# Grr, newaliases only works for an empty DESTDIR.
634			if [ -z "$DESTDIR" ]; then
635				log "newaliases"
636				if [ -z "$dryrun" ]; then
637					newaliases >&3 2>&1
638				fi
639			else
640				NEWALIAS_WARN=yes
641			fi
642			;;
643		/usr/share/certs/trusted/* | /usr/share/certs/untrusted/*)
644			log "certctl rehash"
645			if [ -z "$dryrun" ]; then
646				env DESTDIR=${DESTDIR} certctl rehash >&3 2>&1
647			fi
648			;;
649		/etc/login.conf)
650			log "cap_mkdb ${DESTDIR}$1"
651			if [ -z "$dryrun" ]; then
652				cap_mkdb ${DESTDIR}$1 >&3 2>&1
653			fi
654			;;
655		/etc/master.passwd)
656			log "pwd_mkdb -p -d $DESTDIR/etc ${DESTDIR}$1"
657			if [ -z "$dryrun" ]; then
658				pwd_mkdb -p -d $DESTDIR/etc ${DESTDIR}$1 \
659				    >&3 2>&1
660			fi
661			;;
662		/etc/motd)
663			# /etc/rc.d/motd hardcodes the /etc/motd path.
664			# Don't warn about non-empty DESTDIR's since this
665			# change is only cosmetic anyway.
666			if [ -z "$DESTDIR" ]; then
667				log "sh /etc/rc.d/motd start"
668				if [ -z "$dryrun" ]; then
669					sh /etc/rc.d/motd start >&3 2>&1
670				fi
671			fi
672			;;
673		/etc/services)
674			log "services_mkdb -q -o $DESTDIR/var/db/services.db" \
675			    "${DESTDIR}$1"
676			if [ -z "$dryrun" ]; then
677				services_mkdb -q -o $DESTDIR/var/db/services.db \
678				    ${DESTDIR}$1 >&3 2>&1
679			fi
680			;;
681	esac
682}
683
684# Install the "new" version of a file.  Returns true if it succeeds
685# and false otherwise.
686#
687# $1 - pathname of the file to install (relative to DESTDIR)
688install_new()
689{
690
691	if ! install_dirs $NEWTREE "$DESTDIR" $1; then
692		return 1
693	fi
694	log "cp -Rp ${NEWTREE}$1 ${DESTDIR}$1"
695	if [ -z "$dryrun" ]; then
696		cp -Rp ${NEWTREE}$1 ${DESTDIR}$1 >&3 2>&1
697	fi
698	post_install_file $1
699	return 0
700}
701
702# Install the "resolved" version of a file.  Returns true if it succeeds
703# and false otherwise.
704#
705# $1 - pathname of the file to install (relative to DESTDIR)
706install_resolved()
707{
708
709	# This should always be present since the file is already
710	# there (it caused a conflict).  However, it doesn't hurt to
711	# just be safe.
712	if ! install_dirs $NEWTREE "$DESTDIR" $1; then
713		return 1
714	fi
715
716	# Use cat rather than cp to preserve metadata
717	log "cat ${CONFLICTS}$1 > ${DESTDIR}$1"
718	cat ${CONFLICTS}$1 > ${DESTDIR}$1 2>&3
719	post_install_file $1
720	return 0
721}
722
723# Generate a conflict file when a "new" file conflicts with an
724# existing file in DESTDIR.
725#
726# $1 - pathname of the file that conflicts (relative to DESTDIR)
727new_conflict()
728{
729
730	if [ -n "$dryrun" ]; then
731		return
732	fi
733
734	install_dirs $NEWTREE $CONFLICTS $1
735	diff --changed-group-format='<<<<<<< (local)
736%<=======
737%>>>>>>>> (stock)
738' $DESTDIR/$1 $NEWTREE/$1 > $CONFLICTS/$1
739}
740
741# Remove the "old" version of a file.
742#
743# $1 - pathname of the old file to remove (relative to DESTDIR)
744remove_old()
745{
746	log "rm -f ${DESTDIR}$1"
747	if [ -z "$dryrun" ]; then
748		rm -f ${DESTDIR}$1 >&3 2>&1
749	fi
750	echo "  D $1"
751}
752
753# Update a file that has no local modifications.
754#
755# $1 - pathname of the file to update (relative to DESTDIR)
756update_unmodified()
757{
758	local new old
759
760	# If the old file is a directory, then remove it with rmdir
761	# (this should only happen if the file has changed its type
762	# from a directory to a non-directory).  If the directory
763	# isn't empty, then fail.  This will be reported as a warning
764	# later.
765	if [ -d $DESTDIR/$1 ]; then
766		if empty_destdir $1; then
767			log "rmdir ${DESTDIR}$1"
768			if [ -z "$dryrun" ]; then
769				rmdir ${DESTDIR}$1 >&3 2>&1
770			fi
771		else
772			return 1
773		fi
774
775	# If both the old and new files are regular files, leave the
776	# existing file.  This avoids breaking hard links for /.cshrc
777	# and /.profile.  Otherwise, explicitly remove the old file.
778	elif ! [ -f ${DESTDIR}$1 -a -f ${NEWTREE}$1 ]; then
779		log "rm -f ${DESTDIR}$1"
780		if [ -z "$dryrun" ]; then
781			rm -f ${DESTDIR}$1 >&3 2>&1
782		fi
783	fi
784
785	# If the new file is a directory, note that the old file has
786	# been removed, but don't do anything else for now.  The
787	# directory will be installed if needed when new files within
788	# that directory are installed.
789	if [ -d $NEWTREE/$1 ]; then
790		if empty_dir $NEWTREE/$1; then
791			echo "  D $file"
792		else
793			echo "  U $file"
794		fi
795	elif install_new $1; then
796		echo "  U $file"
797	fi
798	return 0
799}
800
801# Update the FreeBSD ID string in a locally modified file to match the
802# FreeBSD ID string from the "new" version of the file.
803#
804# $1 - pathname of the file to update (relative to DESTDIR)
805update_freebsdid()
806{
807	local new dest file
808
809	# If the FreeBSD ID string is removed from the local file,
810	# there is nothing to do.  In this case, treat the file as
811	# updated.  Otherwise, if either file has more than one
812	# FreeBSD ID string, just punt and let the user handle the
813	# conflict manually.
814	new=`grep -c '\$FreeBSD.*\$' ${NEWTREE}$1`
815	dest=`grep -c '\$FreeBSD.*\$' ${DESTDIR}$1`
816	if [ "$dest" -eq 0 ]; then
817		return 0
818	fi
819	if [ "$dest" -ne 1 -o "$dest" -ne 1 ]; then
820		return 1
821	fi
822
823	# If the FreeBSD ID string in the new file matches the FreeBSD ID
824	# string in the local file, there is nothing to do.
825	new=`grep '\$FreeBSD.*\$' ${NEWTREE}$1`
826	dest=`grep '\$FreeBSD.*\$' ${DESTDIR}$1`
827	if [ "$new" = "$dest" ]; then
828		return 0
829	fi
830
831	# Build the new file in three passes.  First, copy all the
832	# lines preceding the FreeBSD ID string from the local version
833	# of the file.  Second, append the FreeBSD ID string line from
834	# the new version.  Finally, append all the lines after the
835	# FreeBSD ID string from the local version of the file.
836	file=`mktemp $WORKDIR/etcupdate-XXXXXXX`
837	awk '/\$FreeBSD.*\$/ { exit } { print }' ${DESTDIR}$1 >> $file
838	awk '/\$FreeBSD.*\$/ { print }' ${NEWTREE}$1 >> $file
839	awk '/\$FreeBSD.*\$/ { ok = 1; next } { if (ok) print }' \
840	    ${DESTDIR}$1 >> $file
841
842	# As an extra sanity check, fail the attempt if the updated
843	# version of the file has any differences aside from the
844	# FreeBSD ID string.
845	if ! fbsdid_only ${DESTDIR}$1 $file; then
846		rm -f $file
847		return 1
848	fi
849
850	log "cp $file ${DESTDIR}$1"
851	if [ -z "$dryrun" ]; then
852		cp $file ${DESTDIR}$1 >&3 2>&1
853	fi
854	rm -f $file
855	post_install_file $1
856	echo "  M $1"
857	return 0
858}
859
860# Attempt to update a file that has local modifications.  This routine
861# only handles regular files.  If the 3-way merge succeeds without
862# conflicts, the updated file is installed.  If the merge fails, the
863# merged version with conflict markers is left in the CONFLICTS tree.
864#
865# $1 - pathname of the file to merge (relative to DESTDIR)
866merge_file()
867{
868	local res
869
870	# Try the merge to see if there is a conflict.
871	diff3 -E -m ${DESTDIR}$1 ${OLDTREE}$1 ${NEWTREE}$1 > /dev/null 2>&3
872	res=$?
873	case $res in
874		0)
875			# No conflicts, so just redo the merge to the
876			# real file.
877			log "diff3 -E -m ${DESTDIR}$1 ${OLDTREE}$1 ${NEWTREE}$1"
878			if [ -z "$dryrun" ]; then
879				temp=$(mktemp -t etcupdate)
880				diff3 -E -m ${DESTDIR}$1 ${OLDTREE}$1 ${NEWTREE}$1 > ${temp}
881				# Use "cat >" to preserve metadata.
882				cat ${temp} > ${DESTDIR}$1
883				rm -f ${temp}
884			fi
885			post_install_file $1
886			echo "  M $1"
887			;;
888		1)
889			# Conflicts, save a version with conflict markers in
890			# the conflicts directory.
891			if [ -z "$dryrun" ]; then
892				install_dirs $NEWTREE $CONFLICTS $1
893				log "diff3 -m ${DESTDIR}$1 ${CONFLICTS}$1"
894				diff3 -m -L "yours" -L "original" -L "new" \
895				    ${DESTDIR}$1 ${OLDTREE}$1 ${NEWTREE}$1 > \
896				    ${CONFLICTS}$1
897			fi
898			echo "  C $1"
899			;;
900		*)
901			panic "merge failed with status $res"
902			;;
903	esac
904}
905
906# Returns true if a file contains conflict markers from a merge conflict.
907#
908# $1 - pathname of the file to resolve (relative to DESTDIR)
909has_conflicts()
910{
911
912	egrep -q '^(<{7}|\|{7}|={7}|>{7}) ' $CONFLICTS/$1
913}
914
915# Attempt to resolve a conflict.  The user is prompted to choose an
916# action for each conflict.  If the user edits the file, they are
917# prompted again for an action.  The process is very similar to
918# resolving conflicts after an update or merge with Perforce or
919# Subversion.  The prompts are modelled on a subset of the available
920# commands for resolving conflicts with Subversion.
921#
922# $1 - pathname of the file to resolve (relative to DESTDIR)
923resolve_conflict()
924{
925	local command junk
926
927	echo "Resolving conflict in '$1':"
928	edit=
929	while true; do
930		# Only display the resolved command if the file
931		# doesn't contain any conflicts.
932		echo -n "Select: (p) postpone, (df) diff-full, (e) edit,"
933		if ! has_conflicts $1; then
934			echo -n " (r) resolved,"
935		fi
936		echo
937		echo -n "        (h) help for more options: "
938		read command
939		case $command in
940			df)
941				diff -u ${DESTDIR}$1 ${CONFLICTS}$1
942				;;
943			e)
944				$EDITOR ${CONFLICTS}$1
945				;;
946			h)
947				cat <<EOF
948  (p)  postpone    - ignore this conflict for now
949  (df) diff-full   - show all changes made to merged file
950  (e)  edit        - change merged file in an editor
951  (r)  resolved    - accept merged version of file
952  (mf) mine-full   - accept local version of entire file (ignore new changes)
953  (tf) theirs-full - accept new version of entire file (lose local changes)
954  (h)  help        - show this list
955EOF
956				;;
957			mf)
958				# For mine-full, just delete the
959				# merged file and leave the local
960				# version of the file as-is.
961				rm ${CONFLICTS}$1
962				return
963				;;
964			p)
965				return
966				;;
967			r)
968				# If the merged file has conflict
969				# markers, require confirmation.
970				if has_conflicts $1; then
971					echo "File '$1' still has conflicts," \
972					    "are you sure? (y/n) "
973					read junk
974					if [ "$junk" != "y" ]; then
975						continue
976					fi
977				fi
978
979				if ! install_resolved $1; then
980					panic "Unable to install merged" \
981					    "version of $1"
982				fi
983				rm ${CONFLICTS}$1
984				return
985				;;
986			tf)
987				# For theirs-full, install the new
988				# version of the file over top of the
989				# existing file.
990				if ! install_new $1; then
991					panic "Unable to install new" \
992					    "version of $1"
993				fi
994				rm ${CONFLICTS}$1
995				return
996				;;
997			*)
998				echo "Invalid command."
999				;;
1000		esac
1001	done
1002}
1003
1004# Handle a file that has been removed from the new tree.  If the file
1005# does not exist in DESTDIR, then there is nothing to do.  If the file
1006# exists in DESTDIR and is identical to the old version, remove it
1007# from DESTDIR.  Otherwise, whine about the conflict but leave the
1008# file in DESTDIR.  To handle directories, this uses two passes.  The
1009# first pass handles all non-directory files.  The second pass handles
1010# just directories and removes them if they are empty.
1011#
1012# If -F is specified, and the only difference in the file in DESTDIR
1013# is a change in the FreeBSD ID string, then remove the file.
1014#
1015# $1 - pathname of the file (relative to DESTDIR)
1016handle_removed_file()
1017{
1018	local dest file
1019
1020	file=$1
1021	if ignore $file; then
1022		log "IGNORE: removed file $file"
1023		return
1024	fi
1025
1026	compare_fbsdid $DESTDIR/$file $OLDTREE/$file
1027	case $? in
1028		$COMPARE_EQUAL)
1029			if ! [ -d $DESTDIR/$file ]; then
1030				remove_old $file
1031			fi
1032			;;
1033		$COMPARE_ONLYFIRST)
1034			panic "Removed file now missing"
1035			;;
1036		$COMPARE_ONLYSECOND)
1037			# Already removed, nothing to do.
1038			;;
1039		$COMPARE_DIFFTYPE|$COMPARE_DIFFLINKS|$COMPARE_DIFFFILES)
1040			dest=`file_type $DESTDIR/$file`
1041			warn "Modified $dest remains: $file"
1042			;;
1043	esac
1044}
1045
1046# Handle a directory that has been removed from the new tree.  Only
1047# remove the directory if it is empty.
1048#
1049# $1 - pathname of the directory (relative to DESTDIR)
1050handle_removed_directory()
1051{
1052	local dir
1053
1054	dir=$1
1055	if ignore $dir; then
1056		log "IGNORE: removed dir $dir"
1057		return
1058	fi
1059
1060	if [ -d $DESTDIR/$dir -a -d $OLDTREE/$dir ]; then
1061		if empty_destdir $dir; then
1062			log "rmdir ${DESTDIR}$dir"
1063			if [ -z "$dryrun" ]; then
1064				rmdir ${DESTDIR}$dir >/dev/null 2>&1
1065			fi
1066			echo "  D $dir"
1067		else
1068			warn "Non-empty directory remains: $dir"
1069		fi
1070	fi
1071}
1072
1073# Handle a file that exists in both the old and new trees.  If the
1074# file has not changed in the old and new trees, there is nothing to
1075# do.  If the file in the destination directory matches the new file,
1076# there is nothing to do.  If the file in the destination directory
1077# matches the old file, then the new file should be installed.
1078# Everything else becomes some sort of conflict with more detailed
1079# handling.
1080#
1081# $1 - pathname of the file (relative to DESTDIR)
1082handle_modified_file()
1083{
1084	local cmp dest file new newdestcmp old
1085
1086	file=$1
1087	if ignore $file; then
1088		log "IGNORE: modified file $file"
1089		return
1090	fi
1091
1092	compare $OLDTREE/$file $NEWTREE/$file
1093	cmp=$?
1094	if [ $cmp -eq $COMPARE_EQUAL ]; then
1095		return
1096	fi
1097
1098	if [ $cmp -eq $COMPARE_ONLYFIRST -o $cmp -eq $COMPARE_ONLYSECOND ]; then
1099		panic "Changed file now missing"
1100	fi
1101
1102	compare $NEWTREE/$file $DESTDIR/$file
1103	newdestcmp=$?
1104	if [ $newdestcmp -eq $COMPARE_EQUAL ]; then
1105		return
1106	fi
1107
1108	# If the only change in the new file versus the destination
1109	# file is a change in the FreeBSD ID string and -F is
1110	# specified, just install the new file.
1111	if [ -n "$FREEBSD_ID" -a $newdestcmp -eq $COMPARE_DIFFFILES ] && \
1112	    fbsdid_only $NEWTREE/$file $DESTDIR/$file; then
1113		if update_unmodified $file; then
1114			return
1115		else
1116			panic "Updating FreeBSD ID string failed"
1117		fi
1118	fi
1119
1120	# If the local file is the same as the old file, install the
1121	# new file.  If -F is specified and the only local change is
1122	# in the FreeBSD ID string, then install the new file as well.
1123	if compare_fbsdid $OLDTREE/$file $DESTDIR/$file; then
1124		if update_unmodified $file; then
1125			return
1126		fi
1127	fi
1128
1129	# If the file was removed from the dest tree, just whine.
1130	if [ $newdestcmp -eq $COMPARE_ONLYFIRST ]; then
1131		# If the removed file matches an ALWAYS_INSTALL glob,
1132		# then just install the new version of the file.
1133		if always_install $file; then
1134			log "ALWAYS: adding $file"
1135			if ! [ -d $NEWTREE/$file ]; then
1136				if install_new $file; then
1137					echo "  A $file"
1138				fi
1139			fi
1140			return
1141		fi
1142
1143		# If the only change in the new file versus the old
1144		# file is a change in the FreeBSD ID string and -F is
1145		# specified, don't warn.
1146		if [ -n "$FREEBSD_ID" -a $cmp -eq $COMPARE_DIFFFILES ] && \
1147		    fbsdid_only $OLDTREE/$file $NEWTREE/$file; then
1148			return
1149		fi
1150
1151		case $cmp in
1152			$COMPARE_DIFFTYPE)
1153				old=`file_type $OLDTREE/$file`
1154				new=`file_type $NEWTREE/$file`
1155				warn "Remove mismatch: $file ($old became $new)"
1156				;;
1157			$COMPARE_DIFFLINKS)
1158				old=`readlink $OLDTREE/$file`
1159				new=`readlink $NEWTREE/$file`
1160				warn \
1161		"Removed link changed: $file (\"$old\" became \"$new\")"
1162				;;
1163			$COMPARE_DIFFFILES)
1164				warn "Removed file changed: $file"
1165				;;
1166		esac
1167		return
1168	fi
1169
1170	# Treat the file as unmodified and force install of the new
1171	# file if it matches an ALWAYS_INSTALL glob.  If the update
1172	# attempt fails, then fall through to the normal case so a
1173	# warning is generated.
1174	if always_install $file; then
1175		log "ALWAYS: updating $file"
1176		if update_unmodified $file; then
1177			return
1178		fi
1179	fi
1180
1181	# If the only change in the new file versus the old file is a
1182	# change in the FreeBSD ID string and -F is specified, just
1183	# update the FreeBSD ID string in the local file.
1184	if [ -n "$FREEBSD_ID" -a $cmp -eq $COMPARE_DIFFFILES ] && \
1185	    fbsdid_only $OLDTREE/$file $NEWTREE/$file; then
1186		if update_freebsdid $file; then
1187			continue
1188		fi
1189	fi
1190
1191	# If the file changed types between the old and new trees but
1192	# the files in the new and dest tree are both of the same
1193	# type, treat it like an added file just comparing the new and
1194	# dest files.
1195	if [ $cmp -eq $COMPARE_DIFFTYPE ]; then
1196		case $newdestcmp in
1197			$COMPARE_DIFFLINKS)
1198				new=`readlink $NEWTREE/$file`
1199				dest=`readlink $DESTDIR/$file`
1200				warn \
1201			"New link conflict: $file (\"$new\" vs \"$dest\")"
1202				return
1203				;;
1204			$COMPARE_DIFFFILES)
1205				new_conflict $file
1206				echo "  C $file"
1207				return
1208				;;
1209		esac
1210	else
1211		# If the file has not changed types between the old
1212		# and new trees, but it is a different type in
1213		# DESTDIR, then just warn.
1214		if [ $newdestcmp -eq $COMPARE_DIFFTYPE ]; then
1215			new=`file_type $NEWTREE/$file`
1216			dest=`file_type $DESTDIR/$file`
1217			warn "Modified mismatch: $file ($new vs $dest)"
1218			return
1219		fi
1220	fi
1221
1222	case $cmp in
1223		$COMPARE_DIFFTYPE)
1224			old=`file_type $OLDTREE/$file`
1225			new=`file_type $NEWTREE/$file`
1226			dest=`file_type $DESTDIR/$file`
1227			warn "Modified $dest changed: $file ($old became $new)"
1228			;;
1229		$COMPARE_DIFFLINKS)
1230			old=`readlink $OLDTREE/$file`
1231			new=`readlink $NEWTREE/$file`
1232			warn \
1233		"Modified link changed: $file (\"$old\" became \"$new\")"
1234			;;
1235		$COMPARE_DIFFFILES)
1236			merge_file $file
1237			;;
1238	esac
1239}
1240
1241# Handle a file that has been added in the new tree.  If the file does
1242# not exist in DESTDIR, simply copy the file into DESTDIR.  If the
1243# file exists in the DESTDIR and is identical to the new version, do
1244# nothing.  Otherwise, generate a diff of the two versions of the file
1245# and mark it as a conflict.
1246#
1247# $1 - pathname of the file (relative to DESTDIR)
1248handle_added_file()
1249{
1250	local cmp dest file new
1251
1252	file=$1
1253	if ignore $file; then
1254		log "IGNORE: added file $file"
1255		return
1256	fi
1257
1258	compare $DESTDIR/$file $NEWTREE/$file
1259	cmp=$?
1260	case $cmp in
1261		$COMPARE_EQUAL)
1262			return
1263			;;
1264		$COMPARE_ONLYFIRST)
1265			panic "Added file now missing"
1266			;;
1267		$COMPARE_ONLYSECOND)
1268			# Ignore new directories.  They will be
1269			# created as needed when non-directory nodes
1270			# are installed.
1271			if ! [ -d $NEWTREE/$file ]; then
1272				if install_new $file; then
1273					echo "  A $file"
1274				fi
1275			fi
1276			return
1277			;;
1278	esac
1279
1280
1281	# Treat the file as unmodified and force install of the new
1282	# file if it matches an ALWAYS_INSTALL glob.  If the update
1283	# attempt fails, then fall through to the normal case so a
1284	# warning is generated.
1285	if always_install $file; then
1286		log "ALWAYS: updating $file"
1287		if update_unmodified $file; then
1288			return
1289		fi
1290	fi
1291
1292	case $cmp in
1293		$COMPARE_DIFFTYPE)
1294			new=`file_type $NEWTREE/$file`
1295			dest=`file_type $DESTDIR/$file`
1296			warn "New file mismatch: $file ($new vs $dest)"
1297			;;
1298		$COMPARE_DIFFLINKS)
1299			new=`readlink $NEWTREE/$file`
1300			dest=`readlink $DESTDIR/$file`
1301			warn "New link conflict: $file (\"$new\" vs \"$dest\")"
1302			;;
1303		$COMPARE_DIFFFILES)
1304			# If the only change in the new file versus
1305			# the destination file is a change in the
1306			# FreeBSD ID string and -F is specified, just
1307			# install the new file.
1308			if [ -n "$FREEBSD_ID" ] && \
1309			    fbsdid_only $NEWTREE/$file $DESTDIR/$file; then
1310				if update_unmodified $file; then
1311					return
1312				else
1313					panic \
1314					"Updating FreeBSD ID string failed"
1315				fi
1316			fi
1317
1318			new_conflict $file
1319			echo "  C $file"
1320			;;
1321	esac
1322}
1323
1324# Main routines for each command
1325
1326# Build a new tree and save it in a tarball.
1327build_cmd()
1328{
1329	local dir tartree
1330
1331	if [ $# -ne 1 ]; then
1332		echo "Missing required tarball."
1333		echo
1334		usage
1335	fi
1336
1337	log "build command: $1"
1338
1339	# Create a temporary directory to hold the tree
1340	dir=`mktemp -d $WORKDIR/etcupdate-XXXXXXX`
1341	if [ $? -ne 0 ]; then
1342		echo "Unable to create temporary directory."
1343		exit 1
1344	fi
1345	if ! build_tree $dir; then
1346		echo "Failed to build tree."
1347		remove_tree $dir
1348		exit 1
1349	fi
1350	if [ -n "$noroot" ]; then
1351		tartree=@METALOG
1352	else
1353		tartree=.
1354	fi
1355	if ! tar cfj $1 -C $dir $tartree >&3 2>&1; then
1356		echo "Failed to create tarball."
1357		remove_tree $dir
1358		exit 1
1359	fi
1360	remove_tree $dir
1361}
1362
1363# Output a diff comparing the tree at DESTDIR to the current
1364# unmodified tree.  Note that this diff does not include files that
1365# are present in DESTDIR but not in the unmodified tree.
1366diff_cmd()
1367{
1368	local file
1369
1370	if [ $# -ne 0 ]; then
1371		usage
1372	fi
1373
1374	# Requires an unmodified tree to diff against.
1375	if ! [ -d $NEWTREE ]; then
1376		echo "Reference tree to diff against unavailable."
1377		exit 1
1378	fi
1379
1380	# Unfortunately, diff alone does not quite provide the right
1381	# level of options that we want, so improvise.
1382	for file in `(cd $NEWTREE; find .) | sed -e 's/^\.//'`; do
1383		if ignore $file; then
1384			continue
1385		fi
1386
1387		diffnode $NEWTREE "$DESTDIR" $file "stock" "local"
1388	done
1389}
1390
1391# Just extract a new tree into NEWTREE either by building a tree or
1392# extracting a tarball.  This can be used to bootstrap updates by
1393# initializing the current "stock" tree to match the currently
1394# installed system.
1395#
1396# Unlike 'update', this command does not rotate or preserve an
1397# existing NEWTREE, it just replaces any existing tree.
1398extract_cmd()
1399{
1400
1401	if [ $# -ne 0 ]; then
1402		usage
1403	fi
1404
1405	log "extract command: tarball=$tarball"
1406
1407	# Create a temporary directory to hold the tree
1408	dir=`mktemp -d $WORKDIR/etcupdate-XXXXXXX`
1409	if [ $? -ne 0 ]; then
1410		echo "Unable to create temporary directory."
1411		exit 1
1412	fi
1413
1414	extract_tree $dir
1415
1416	if [ -d $NEWTREE ]; then
1417		if ! remove_tree $NEWTREE; then
1418			echo "Unable to remove current tree."
1419			remove_tree $dir
1420			exit 1
1421		fi
1422	fi
1423
1424	if ! mv $dir $NEWTREE >&3 2>&1; then
1425		echo "Unable to rename temp tree to current tree."
1426		remove_tree $dir
1427		exit 1
1428	fi
1429}
1430
1431# Resolve conflicts left from an earlier merge.
1432resolve_cmd()
1433{
1434	local conflicts
1435
1436	if [ $# -ne 0 ]; then
1437		usage
1438	fi
1439
1440	if ! [ -d $CONFLICTS ]; then
1441		return
1442	fi
1443
1444	if ! [ -d $NEWTREE ]; then
1445		echo "The current tree is not present to resolve conflicts."
1446		exit 1
1447	fi
1448
1449	conflicts=`(cd $CONFLICTS; find . ! -type d) | sed -e 's/^\.//'`
1450	for file in $conflicts; do
1451		resolve_conflict $file
1452	done
1453
1454	if [ -n "$NEWALIAS_WARN" ]; then
1455		warn "Needs update: /etc/mail/aliases.db" \
1456		    "(requires manual update via newaliases(1))"
1457		echo
1458		echo "Warnings:"
1459		echo "  Needs update: /etc/mail/aliases.db" \
1460		    "(requires manual update via newaliases(1))"
1461	fi
1462}
1463
1464# Restore files to the stock version.  Only files with a local change
1465# are restored from the stock version.
1466revert_cmd()
1467{
1468	local cmp file
1469
1470	if [ $# -eq 0 ]; then
1471		usage
1472	fi
1473
1474	for file; do
1475		log "revert $file"
1476
1477		if ! [ -e $NEWTREE/$file ]; then
1478			echo "File $file does not exist in the current tree."
1479			exit 1
1480		fi
1481		if [ -d $NEWTREE/$file ]; then
1482			echo "File $file is a directory."
1483			exit 1
1484		fi
1485
1486		compare $DESTDIR/$file $NEWTREE/$file
1487		cmp=$?
1488		if [ $cmp -eq $COMPARE_EQUAL ]; then
1489			continue
1490		fi
1491
1492		if update_unmodified $file; then
1493			# If this file had a conflict, clean up the
1494			# conflict.
1495			if [ -e $CONFLICTS/$file ]; then
1496				if ! rm $CONFLICTS/$file >&3 2>&1; then
1497					echo "Failed to remove conflict " \
1498					     "for $file".
1499				fi
1500			fi
1501		fi
1502	done
1503}
1504
1505# Report a summary of the previous merge.  Specifically, list any
1506# remaining conflicts followed by any warnings from the previous
1507# update.
1508status_cmd()
1509{
1510
1511	if [ $# -ne 0 ]; then
1512		usage
1513	fi
1514
1515	if [ -d $CONFLICTS ]; then
1516		(cd $CONFLICTS; find . ! -type d) | sed -e 's/^\./  C /'
1517	fi
1518	if [ -s $WARNINGS ]; then
1519		echo "Warnings:"
1520		cat $WARNINGS
1521	fi
1522}
1523
1524# Perform an actual merge.  The new tree can either already exist (if
1525# rerunning a merge), be extracted from a tarball, or generated from a
1526# source tree.
1527update_cmd()
1528{
1529	local dir new old
1530
1531	if [ $# -ne 0 ]; then
1532		usage
1533	fi
1534
1535	log "update command: rerun=$rerun tarball=$tarball preworld=$preworld"
1536
1537	if [ `id -u` -ne 0 ]; then
1538		echo "Must be root to update a tree."
1539		exit 1
1540	fi
1541
1542	# Enforce a sane umask
1543	umask 022
1544
1545	# XXX: Should existing conflicts be ignored and removed during
1546	# a rerun?
1547
1548	# Trim the conflicts tree.  Whine if there is anything left.
1549	if [ -e $CONFLICTS ]; then
1550		find -d $CONFLICTS -type d -empty -delete >&3 2>&1
1551		rmdir $CONFLICTS >&3 2>&1
1552	fi
1553	if [ -d $CONFLICTS ]; then
1554		echo "Conflicts remain from previous update, aborting."
1555		exit 1
1556	fi
1557
1558	# Save tree names to use for rotation later.
1559	old=$OLDTREE
1560	new=$NEWTREE
1561	if [ -z "$rerun" ]; then
1562		# Extract the new tree to a temporary directory.  The
1563	        # trees are only rotated after a successful update to
1564	        # avoid races if an update command is interrupted
1565	        # before it completes.
1566		dir=`mktemp -d $WORKDIR/etcupdate-XXXXXXX`
1567		if [ $? -ne 0 ]; then
1568			echo "Unable to create temporary directory."
1569			exit 1
1570		fi
1571
1572		# Populate the new tree.
1573		extract_tree $dir
1574
1575		# Compare the new tree against the previous tree.  For
1576		# the preworld case OLDTREE already points to the
1577		# current stock tree.
1578		if [ -z "$preworld" ]; then
1579			OLDTREE=$NEWTREE
1580		fi
1581		NEWTREE=$dir
1582	fi
1583
1584	if ! [ -d $OLDTREE ]; then
1585		cat <<EOF
1586No previous tree to compare against, a sane comparison is not possible.
1587EOF
1588		log "No previous tree to compare against."
1589		if [ -n "$dir" ]; then
1590			if [ -n "$rerun" ]; then
1591				panic "Should not have a temporary directory"
1592			fi
1593			remove_tree $dir
1594		fi
1595		exit 1
1596	fi
1597
1598	# Build lists of nodes in the old and new trees.
1599	(cd $OLDTREE; find .) | sed -e 's/^\.//' | sort > $WORKDIR/old.files
1600	(cd $NEWTREE; find .) | sed -e 's/^\.//' | sort > $WORKDIR/new.files
1601
1602	# Split the files up into three groups using comm.
1603	comm -23 $WORKDIR/old.files $WORKDIR/new.files > $WORKDIR/removed.files
1604	comm -13 $WORKDIR/old.files $WORKDIR/new.files > $WORKDIR/added.files
1605	comm -12 $WORKDIR/old.files $WORKDIR/new.files > $WORKDIR/both.files
1606
1607	# Initialize conflicts and warnings handling.
1608	rm -f $WARNINGS
1609	mkdir -p $CONFLICTS
1610	if ! chmod 0700 ${CONFLICTS}; then
1611		panic "Unable to set permissions on conflicts directory"
1612	fi
1613
1614	# Ignore removed files for the pre-world case.  A pre-world
1615	# update uses a stripped-down tree.
1616	if [ -n "$preworld" ]; then
1617		> $WORKDIR/removed.files
1618	fi
1619
1620	# The order for the following sections is important.  In the
1621	# odd case that a directory is converted into a file, the
1622	# existing subfiles need to be removed if possible before the
1623	# file is converted.  Similarly, in the case that a file is
1624	# converted into a directory, the file needs to be converted
1625	# into a directory if possible before the new files are added.
1626
1627	# First, handle removed files.
1628	for file in `cat $WORKDIR/removed.files`; do
1629		handle_removed_file $file
1630	done
1631
1632	# For the directory pass, reverse sort the list to effect a
1633	# depth-first traversal.  This is needed to ensure that if a
1634	# directory with subdirectories is removed, the entire
1635	# directory is removed if there are no local modifications.
1636	for file in `sort -r $WORKDIR/removed.files`; do
1637		handle_removed_directory $file
1638	done
1639
1640	# Second, handle files that exist in both the old and new
1641	# trees.
1642	for file in `cat $WORKDIR/both.files`; do
1643		handle_modified_file $file
1644	done
1645
1646	# Finally, handle newly added files.
1647	for file in `cat $WORKDIR/added.files`; do
1648		handle_added_file $file
1649	done
1650
1651	if [ -n "$NEWALIAS_WARN" ]; then
1652		warn "Needs update: /etc/mail/aliases.db" \
1653		    "(requires manual update via newaliases(1))"
1654	fi
1655
1656	# Run any special one-off commands after an update has completed.
1657	post_update
1658
1659	if [ -s $WARNINGS ]; then
1660		echo "Warnings:"
1661		cat $WARNINGS
1662	fi
1663
1664	# If this was a dryrun, remove the temporary tree if we built
1665	# a new one.
1666	if [ -n "$dryrun" ]; then
1667		if [ -n "$dir" ]; then
1668			if [ -n "$rerun" ]; then
1669				panic "Should not have a temporary directory"
1670			fi
1671			remove_tree $dir
1672		fi
1673		return
1674	fi
1675
1676	# Finally, rotate any needed trees.
1677	if [ "$new" != "$NEWTREE" ]; then
1678		if [ -n "$rerun" ]; then
1679			panic "Should not have a temporary directory"
1680		fi
1681		if [ -z "$dir" ]; then
1682			panic "Should have a temporary directory"
1683		fi
1684
1685		# Rotate the old tree if needed
1686		if [ "$old" != "$OLDTREE" ]; then
1687			if [ -n "$preworld" ]; then
1688				panic "Old tree should be unchanged"
1689			fi
1690
1691			if ! remove_tree $old; then
1692				echo "Unable to remove previous old tree."
1693				exit 1
1694			fi
1695
1696			if ! mv $OLDTREE $old >&3 2>&1; then
1697				echo "Unable to rename old tree."
1698				exit 1
1699			fi
1700		fi
1701
1702		# Rotate the new tree.  Remove a previous pre-world
1703		# tree if it exists.
1704		if [ -d $new ]; then
1705			if [ -z "$preworld" ]; then
1706				panic "New tree should be rotated to old"
1707			fi
1708			if ! remove_tree $new; then
1709				echo "Unable to remove previous pre-world tree."
1710				exit 1
1711			fi
1712		fi
1713
1714		if ! mv $NEWTREE $new >&3 2>&1; then
1715			echo "Unable to rename current tree."
1716			exit 1
1717		fi
1718	fi
1719}
1720
1721# Determine which command we are executing.  A command may be
1722# specified as the first word.  If one is not specified then 'update'
1723# is assumed as the default command.
1724command="update"
1725if [ $# -gt 0 ]; then
1726	case "$1" in
1727		build|diff|extract|status|resolve|revert)
1728			command="$1"
1729			shift
1730			;;
1731		-*)
1732			# If first arg is an option, assume the
1733			# default command.
1734			;;
1735		*)
1736			usage
1737			;;
1738	esac
1739fi
1740
1741# Set default variable values.
1742
1743# The path to the source tree used to build trees.
1744SRCDIR=/usr/src
1745
1746# The destination directory where the modified files live.
1747DESTDIR=
1748
1749# Ignore changes in the FreeBSD ID string.
1750FREEBSD_ID=
1751
1752# Files that should always have the new version of the file installed.
1753ALWAYS_INSTALL=
1754
1755# Files to ignore and never update during a merge.
1756IGNORE_FILES=
1757
1758# The path to the make binary
1759MAKE_CMD=make
1760
1761# Flags to pass to 'make' when building a tree.
1762MAKE_OPTIONS=
1763
1764# Include a config file if it exists.  Note that command line options
1765# override any settings in the config file.  More details are in the
1766# manual, but in general the following variables can be set:
1767# - ALWAYS_INSTALL
1768# - DESTDIR
1769# - EDITOR
1770# - FREEBSD_ID
1771# - IGNORE_FILES
1772# - LOGFILE
1773# - MAKE_CMD
1774# - MAKE_OPTIONS
1775# - SRCDIR
1776# - WORKDIR
1777if [ -r /etc/etcupdate.conf ]; then
1778	. /etc/etcupdate.conf
1779fi
1780
1781# Parse command line options
1782tarball=
1783rerun=
1784always=
1785dryrun=
1786ignore=
1787nobuild=
1788preworld=
1789noroot=
1790while getopts "d:m:nprs:t:A:BD:FI:L:M:N" option; do
1791	case "$option" in
1792		d)
1793			WORKDIR=$OPTARG
1794			;;
1795		m)
1796			MAKE_CMD=$OPTARG
1797			;;
1798		n)
1799			dryrun=YES
1800			;;
1801		p)
1802			preworld=YES
1803			;;
1804		r)
1805			rerun=YES
1806			;;
1807		s)
1808			SRCDIR=$OPTARG
1809			;;
1810		t)
1811			tarball=$OPTARG
1812			;;
1813		A)
1814			# To allow this option to be specified
1815			# multiple times, accumulate command-line
1816			# specified patterns in an 'always' variable
1817			# and use that to overwrite ALWAYS_INSTALL
1818			# after parsing all options.  Need to be
1819			# careful here with globbing expansion.
1820			set -o noglob
1821			always="$always $OPTARG"
1822			set +o noglob
1823			;;
1824		B)
1825			nobuild=YES
1826			;;
1827		D)
1828			DESTDIR=$OPTARG
1829			;;
1830		F)
1831			FREEBSD_ID=YES
1832			;;
1833		I)
1834			# To allow this option to be specified
1835			# multiple times, accumulate command-line
1836			# specified patterns in an 'ignore' variable
1837			# and use that to overwrite IGNORE_FILES after
1838			# parsing all options.  Need to be careful
1839			# here with globbing expansion.
1840			set -o noglob
1841			ignore="$ignore $OPTARG"
1842			set +o noglob
1843			;;
1844		L)
1845			LOGFILE=$OPTARG
1846			;;
1847		M)
1848			MAKE_OPTIONS="$OPTARG"
1849			;;
1850		N)
1851			noroot=YES
1852			;;
1853		*)
1854			echo
1855			usage
1856			;;
1857	esac
1858done
1859shift $((OPTIND - 1))
1860
1861# Allow -A command line options to override ALWAYS_INSTALL set from
1862# the config file.
1863set -o noglob
1864if [ -n "$always" ]; then
1865	ALWAYS_INSTALL="$always"
1866fi
1867
1868# Allow -I command line options to override IGNORE_FILES set from the
1869# config file.
1870if [ -n "$ignore" ]; then
1871	IGNORE_FILES="$ignore"
1872fi
1873set +o noglob
1874
1875# Where the "old" and "new" trees are stored.
1876WORKDIR=${WORKDIR:-$DESTDIR/var/db/etcupdate}
1877
1878# Log file for verbose output from program that are run.  The log file
1879# is opened on fd '3'.
1880LOGFILE=${LOGFILE:-$WORKDIR/log}
1881
1882# The path of the "old" tree
1883OLDTREE=$WORKDIR/old
1884
1885# The path of the "new" tree
1886NEWTREE=$WORKDIR/current
1887
1888# The path of the "conflicts" tree where files with merge conflicts are saved.
1889CONFLICTS=$WORKDIR/conflicts
1890
1891# The path of the "warnings" file that accumulates warning notes from an update.
1892WARNINGS=$WORKDIR/warnings
1893
1894# Use $EDITOR for resolving conflicts.  If it is not set, default to vi.
1895EDITOR=${EDITOR:-/usr/bin/vi}
1896
1897# Files that need to be updated before installworld.
1898PREWORLD_FILES="etc/master.passwd etc/group"
1899
1900# Handle command-specific argument processing such as complaining
1901# about unsupported options.  Since the configuration file is always
1902# included, do not complain about extra command line arguments that
1903# may have been set via the config file rather than the command line.
1904case $command in
1905	update)
1906		if [ -n "$rerun" -a -n "$tarball" ]; then
1907			echo "Only one of -r or -t can be specified."
1908			echo
1909			usage
1910		fi
1911		if [ -n "$rerun" -a -n "$preworld" ]; then
1912			echo "Only one of -p or -r can be specified."
1913			echo
1914			usage
1915		fi
1916		;;
1917	build|diff|status|revert)
1918		if [ -n "$dryrun" -o -n "$rerun" -o -n "$tarball" -o \
1919		     -n "$preworld" ]; then
1920			usage
1921		fi
1922		;;
1923	resolve)
1924		if [ -n "$dryrun" -o -n "$rerun" -o -n "$tarball" ]; then
1925			usage
1926		fi
1927		;;
1928	extract)
1929		if [ -n "$dryrun" -o -n "$rerun" -o -n "$preworld" ]; then
1930			usage
1931		fi
1932		;;
1933esac
1934
1935# Pre-world mode uses a different set of trees.  It leaves the current
1936# tree as-is so it is still present for a full etcupdate run after the
1937# world install is complete.  Instead, it installs a few critical files
1938# into a separate tree.
1939if [ -n "$preworld" ]; then
1940	OLDTREE=$NEWTREE
1941	NEWTREE=$WORKDIR/preworld
1942fi
1943
1944# Open the log file.  Don't truncate it if doing a minor operation so
1945# that a minor operation doesn't lose log info from a major operation.
1946if ! mkdir -p $WORKDIR 2>/dev/null; then
1947	echo "Failed to create work directory $WORKDIR"
1948fi
1949
1950case $command in
1951	diff|resolve|revert|status)
1952		exec 3>>$LOGFILE
1953		;;
1954	*)
1955		exec 3>$LOGFILE
1956		;;
1957esac
1958
1959${command}_cmd "$@"
1960