diff options
| -rw-r--r-- | Makefile | 2 | ||||
| -rw-r--r-- | shutdown | 66 |
2 files changed, 67 insertions, 1 deletions
@@ -1,5 +1,5 @@ -SCRIPTS = init +SCRIPTS = init shutdown all: diff --git a/shutdown b/shutdown new file mode 100644 index 0000000..09281dd --- /dev/null +++ b/shutdown @@ -0,0 +1,66 @@ +#!/bin/sh + +fail(){ + echo "$@" >&2 + # The behaviour on failure of systemd when shutting down without a + # shutdownramfs is to freeze if it fails, but the behaviour of an initramfs + # on failure is to drop you into a recovery shell. The latter seems more + # useful. + exec /bin/sh +} + +startswith(){ + # Filter out lines that don't start with $1 + # grep ^EXPR is usually sufficient, but would require escaping of EXPR. + # Instead this compares the line to the line with its prefix stripped, + # so if the line is different, then it started with that prefix. + # It's ugly, but is less logic than escaping the regular expression and + # using grep, more reliable than not making any effort to escape, and + # less surprising than requiring the parameter to be pre-escaped. + while read -r line; do + if [ "${line#"$1"}" != "$line" ]; then + printf '%s\n' "$line" + fi + done +} + +recursive_umount(){ + # Recursively unmount every mountpoint under $1. + # This works by filtering to select mountpoints from mountinfo that start + # with the absolute path of the directory given. + # It unmounts in reverse-order, so that it may unmount dependent mounts + # first, and it has to handle the paths having octal escape sequences. + set -- "$(readlink -f "$1")" + cut -d' ' -f5 /proc/self/mountinfo | startswith "$1" \ + | sort -r | while read -r mp; do + umount "$(echo -e "$mp")" + done +} + +# Give the rootfs another chance to write its state to disk. +sync + +# Kill any http://www.freedesktop.org/wiki/Software/systemd/RootStorageDaemons/ +# as we don't have any facility to cleanly shut them down in this initramfs. +killall5 + +# Recursively unmount the old root, so they have a chance of performing +# unmount-time cleanup. +recursive_umount /oldroot + +case "$1" in +reboot|poweroff|halt) + if ! "$1" -f; then + fail "$1 command failed" + fi + ;; +kexec) + # probably don't have this, but we'll try anyway + if ! kexec -e; then + fail "$1 command failed" + fi + ;; +*) + fail "Unrecognized shutdown verb $1" + ;; +esac |