exit 1
;;
esac
-ARGS="$@"
-do_real_cmd()
+usage()
{
- case "$ARGS" in
- (*--molly-guard-do-nothing*)
- ARGS0="${ARGS%%--molly-guard-do-nothing*}"
- ARGS1="${ARGS##*--molly-guard-do-nothing}"
- echo "$ME: would run: $EXEC ${ARGS0# } ${ARGS1# }"
- exit 0;;
- *) eval exec $EXEC "$ARGS";;
+ cat <<-_eousage
+ Usage: $ME [options]
+ (shielding $EXEC)
+
+ Instead of invoking $EXEC directly, $ME will prompt the user for the
+ machine's hostname to guard against accidental shutdowns/reboots, if the
+ current shell is a child of an SSH connection (or --pretend-ssh) has been
+ given on the command line, if the shell is connected to an interactive
+ terminal, and the actual command to execute is does not involve --help or is
+ \`shutdown -c'.
+
+ Only if the user enters the machine's hostname correctly will $ME take
+ action. Specifying --molly-guard-do-nothing as argument to the command will
+ make $ME echo the command it would execute rather than actually executing
+ it.
+
+ The actual command's help output follows:
+
+ _eousage
+}
+
+ARGS=
+DO_NOTHING=0
+PRETEND_SSH=0
+for arg in "$@"; do
+ case "$arg" in
+ (*-molly-guard-do-nothing) DO_NOTHING=1;;
+ (*-help)
+ usage 2>&1
+ eval $EXEC --help 2>&1
+ exit 0
+ ;;
+ (*-pretend-ssh) PRETEND_SSH=1;;
+ *) ARGS="${ARGS:+$ARGS }$arg";;
esac
+done
+
+do_real_cmd()
+{
+ if [ $DO_NOTHING -eq 1 ]; then
+ echo "$ME: would run: $EXEC $ARGS"
+ exit 0
+ else
+ eval exec $EXEC "$ARGS"
+ fi
}
+if [ $DO_NOTHING -eq 1 ]; then
+ echo "I: demo mode; $ME will not do anything due to --molly-guard-do-nothing."
+fi
+
# require an interactive terminal connected to stdin
test -t 0 || do_real_cmd
# only run if we are being called over SSH, that is if the current terminal
# was created by sshd.
PTS=$(readlink /proc/$$/fd/0)
-pgrep -f "^sshd.+${PTS#/dev/}[[:space:]]*$" >/dev/null || do_real_cmd
+if ! pgrep -f "^sshd.+${PTS#/dev/}[[:space:]]*$" >/dev/null; then
+ if [ $PRETEND_SSH -eq 1 ]; then
+ echo "I: this is not an SSH session, but --pretend-ssh was given..."
+ else
+ do_real_cmd
+ fi
+else
+ echo "W: $ME: SSH session detected!"
+fi
-# pass through help commands
+# pass through certain commands
case "$CMD $ARGS" in
- (shutdown\ *-c*) do_real_cmd;;
- (shutdown\ *-h*) do_real_cmd;;
- (*--help*) do_real_cmd;;
- *) :;;
+ (*shutdown\ *-c*)
+ echo "I: executing $CMD $ARGS regardless of SSH session."
+ do_real_cmd
+ ;;
esac
HOSTNAME="$(hostname)"
trap 'echo;sigh' 1 2 3 9 10 12 15
-echo "$ME: SSH session detected!"
echo -n "Please type in hostname of the machine to $CMD: "
read HOSTNAME_USER || :