#!/bin/sh # # shutdown -- wrapper script to guard against accidental shutdowns # # Copyright © martin f. krafft # Released under the terms of the Artistic Licence 2.0 # set -eu ME=molly-guard VERSION=0.4 SCRIPTSDIR=/etc/molly-guard/run.d SCRIPTSDIR="${0%/*}/run.d" CMD="${0##*/}" EXEC="/sbin/$CMD" case "$CMD" in halt|reboot|shutdown|poweroff) if [ ! -f $EXEC ]; then echo "E: $ME: not a regular file: $EXEC" >&2 exit 4 fi if [ ! -x $EXEC ]; then echo "E: $ME: not an executable: $EXEC" >&2 exit 3 fi ;; *) echo "E: $ME: unsupported command: $CMD" >&2 exit 1 ;; esac usage() { cat <<-_eousage Usage: $ME [options] [-- script options] (shielding $EXEC) molly-guard's primary goal is to guard against accidental shutdowns/reboots. $ME will run all scripts in $SCRIPTSDIR and only invokes $EXEC if all scripts exited successfully. Specifying --molly-guard-do-nothing as argument to the command will make $ME echo the command it would execute rather than actually executing it. Options following the double hyphen will be passed unchanged to the scripts. Please see molly-guard(8) for more information. The actual command's help output follows: _eousage } CMDARGS= SCRIPTARGS= END_OF_ARGS=0 DO_NOTHING=0 for arg in "$@"; do case "$arg" in (*-molly-guard-do-nothing) DO_NOTHING=1;; (*-help) usage 2>&1 eval $EXEC --help 2>&1 exit 0 ;; --) END_OF_ARGS=1;; *) if [ $END_OF_ARGS -eq 0 ]; then CMDARGS="${args:+$args }$arg" else SCRIPTARGS="${args:+$args }--arg $arg" fi ;; esac done do_real_cmd() { if [ $DO_NOTHING -eq 1 ]; then echo "$ME: would run: $EXEC $CMDARGS" exit 0 else eval exec $EXEC "$CMDARGS" fi } if [ $DO_NOTHING -eq 1 ]; then echo "I: demo mode; $ME will not do anything due to --molly-guard-do-nothing." >&2 fi # pass through certain commands case "$CMD $CMDARGS" in (*shutdown\ *-c*) # allow canceling shutdowns echo "I: executing $CMD $CMDARGS regardless of check results." >&2 do_real_cmd ;; esac MOLLYGUARD_CMD=$CMD; export MOLLYGUARD_CMD MOLLYGUARD_DO_NOTHING=$DO_NOTHING; export MOLLYGUARD_DO_NOTHING MOLLYGUARD_SETTINGS="/etc/default/$ME"; export MOLLYGUARD_SETTINGS for script in $(run-parts --test $SCRIPTSDIR); do ret=0 eval $script $SCRIPTARGS || ret=$? if [ $ret -ne 0 ]; then echo "W: aborting $CMD due to ${script##*/} exiting with code $ret." >&2 exit $ret fi done do_real_cmd