nixpkgs/modules/system/upstart-events/halt.nix
Eelco Dolstra bed6fd6a61 * `umount -f' causes lots of problems, so don't do it.
svn path=/nixos/trunk/; revision=16688
2009-08-11 21:08:05 +00:00

125 lines
3.4 KiB
Nix

{pkgs, config, ...}:
###### implementation
let
inherit (pkgs) bash utillinux;
jobFun = event : {
name = "sys-" + event;
job = ''
start on ${event}
script
set +e # continue in case of errors
exec < /dev/tty1 > /dev/tty1 2>&1
echo ""
echo "<<< SYSTEM SHUTDOWN >>>"
echo ""
export PATH=${utillinux}/bin:${utillinux}/sbin:$PATH
# Set the hardware clock to the system time.
echo "setting the hardware clock..."
hwclock --systohc --utc
# Do an initial sync just in case.
sync
# Kill all remaining processes except init and this one.
echo "sending the TERM signal to all processes..."
kill -TERM -1
sleep 1 # wait briefly
echo "sending the KILL signal to all processes..."
kill -KILL -1
# Unmount helper functions.
getMountPoints() {
cat /proc/mounts \
| grep -v '^rootfs' \
| sed 's|^[^ ]\+ \+\([^ ]\+\).*|\1|' \
| grep -v '/proc\|/sys\|/dev'
}
getDevice() {
local mountPoint=$1
cat /proc/mounts \
| grep -v '^rootfs' \
| grep "^[^ ]\+ \+$mountPoint \+" \
| sed 's|^\([^ ]\+\).*|\1|'
}
# Unmount file systems. We repeat this until no more file systems
# can be unmounted. This is to handle loopback devices, file
# systems mounted on other file systems and so on.
tryAgain=1
while test -n "$tryAgain"; do
tryAgain=
for mp in $(getMountPoints); do
device=$(getDevice $mp)
echo "unmounting $mp..."
# Note: don't use `umount -f'; it's very buggy.
# (For instance, when applied to a bind-mount it
# unmounts the target of the bind-mount.) !!! But
# we should use `-f' for NFS.
if umount -n "$mp"; then
if test "$mp" != /; then tryAgain=1; fi
else
# `-i' is to workaround a bug in mount.cifs (it
# doesn't recognise the `remount' option, and
# instead mounts the FS again).
mount -n -i -o remount,ro "$mp"
fi
# Hack: work around a bug in mount (mount -o remount on a
# loop device forgets the loop=/dev/loopN entry in
# /etc/mtab).
if echo "$device" | grep -q '/dev/loop'; then
echo "removing loop device $device..."
losetup -d "$device"
fi
done
done
# Final sync.
sync
# Either reboot or power-off the system. Note that the "halt"
# event also does a power-off.
if test ${event} = reboot; then
echo "rebooting..."
sleep 1
exec reboot -f
else
echo "powering off..."
sleep 1
exec halt -f -p
fi
end script
'';
};
in
{
services = {
extraJobs = map jobFun ["reboot" "halt" "system-halt" "power-off"];
};
}