Commit a7a05deb authored by Jan Alexander Steffens (heftig)'s avatar Jan Alexander Steffens (heftig)
Browse files

lib/common.sh: Introduce locking helper functions 

Reduces code duplication.

With makechrootpkg not calling mkarchroot anymore,
the lock handover protocol is unneeded.

arch-nspawn does not do any locking, so add protection to archbuild.
parent 0e98bd8c

archbuild.in

+2 −6
Original line number Diff line number Diff line
@@ -51,12 +51,7 @@ if ${clean_first} || [[ ! -d "${chroots}/${repo}-${arch}" ]]; then 
		[[ -d $copy ]] || continue

		msg2 "Deleting chroot copy '$(basename "${copy}")'..."



		exec 9>"$copydir.lock"

		if ! flock -n 9; then

			stat_busy "Locking chroot copy '$copy'"

			flock 9

			stat_done

		fi

		lock 9 "$copydir.lock" "Locking chroot copy '$copy'"



		if [[ "$(stat -f -c %T "${copy}")" == btrfs ]]; then

			{ type -P btrfs && btrfs subvolume delete "${copy}"; } &>/dev/null
@@ -73,6 +68,7 @@ if ${clean_first} || [[ ! -d "${chroots}/${repo}-${arch}" ]]; then 
		"${chroots}/${repo}-${arch}/root" \

		"${base_packages[@]}" || abort

else

	lock 9 "${chroots}/${repo}-${arch}/root.lock" "Locking clean chroot"

	setarch ${arch} arch-nspawn \

		-C "@pkgdatadir@/pacman-${repo}.conf" \

		-M "@pkgdatadir@/makepkg-${arch}.conf" \

lib/common.sh

+24 −0
Original line number Diff line number Diff line
@@ -130,3 +130,27 @@ get_full_version() { 
		fi

	fi

}



##

#  usage : lock( $fd, $file, $message )

##

lock() {

	eval "exec $1>"'"$2"'

	if ! flock -n $1; then

		stat_busy "$3"

		flock $1

		stat_done

	fi

}



##

#  usage : slock( $fd, $file, $message )

##

slock() {

	eval "exec $1>"'"$2"'

	if ! flock -sn $1; then

		stat_busy "$3"

		flock -s $1

		stat_done

	fi

}

makechrootpkg.in

+2 −14
Original line number Diff line number Diff line
@@ -120,24 +120,12 @@ umask 0022 
chroottype=$(stat -f -c %T "$chrootdir")



# Lock the chroot we want to use. We'll keep this lock until we exit.

# Note this is the same FD number as in mkarchroot

exec 9>"$copydir.lock"

if ! flock -n 9; then

	stat_busy "Locking chroot copy [$copy]"

	flock 9

	stat_done

fi

lock 9 "$copydir.lock" "Locking chroot copy [$copy]"



if [[ ! -d $copydir ]] || $clean_first; then

	# Get a read lock on the root chroot to make

	# sure we don't clone a half-updated chroot

	exec 8>"$chrootdir/root.lock"



	if ! flock -sn 8; then

		stat_busy "Locking clean chroot"

		flock -s 8

		stat_done

	fi

	slock 8 "$chrootdir/root.lock" "Locking clean chroot"



	stat_busy "Creating clean working copy [$copy]"

	if [[ "$chroottype" == btrfs ]]; then

mkarchroot.in

+1 −17
Original line number Diff line number Diff line
@@ -49,29 +49,13 @@ else 
	cache_dirs=(${cache_dir})

fi



# {{{ functions

chroot_lock () {

	# Only reopen the FD if it wasn't handed to us

	if [[ $(readlink -f /dev/fd/9) != "${working_dir}.lock" ]]; then

	  exec 9>"${working_dir}.lock"

	fi



	# Lock the chroot. Take note of the FD number.

	if ! flock -n 9; then

		stat_busy "Locking chroot"

		flock 9

		stat_done

	fi

}

# }}}



umask 0022



[[ -e $working_dir ]] && die "Working directory '$working_dir' already exists"



mkdir -p "$working_dir"



chroot_lock

lock 9 "${working_dir}.lock" "Locking chroot"



if [[ $(stat -f -c %T "$working_dir") == btrfs ]]; then

	rmdir "$working_dir"