chrootctl.in

#!/bin/bash

m4_include(common)
status() { out "Status:" "$@"; }
running() { eval "status running; return 0"; }
stopped() { eval "status stopped; return 1"; }

source_profile(){
    PROFILE=/etc/chroot-service/profile
    [ -f $PROFILE ] && source $PROFILE
}
# init
chroot_init(){
    source_profile
    out "$CHROOT $args $INIT"
    exec $CHROOT $args $INIT
}
# Add $1 to $accepted_args if $1 not in.
process_arg() {
    local arg="$1"
    case " ${accepted_args[*]} " in
        *" $arg "*)
            ;;
        *)
            out "$arg"
            accepted_args+=("$arg")
            ;;
    esac
}
# Get all active chroot from /proc/*/root.
chroot_list() {
    local accepted_args=()
    for symlink in /proc/*/root; do
        [[ -L $symlink ]] && process_arg $(realpath "$symlink")
    done
}
# check status
chroot_status(){
    local chrootdir=$1
    case $chrootdir in
        /)  status running; return 0    ;;
        '') status stopped; return 1    ;;
    esac
    for active_chroot in $(chroot_list) ;do
        case $active_chroot in
            *"/$chrootdir"|"$chrootdir")
                status running
                return 0    ;;
        esac
    done
    status stopped
    return 1
}
# exec command
chroot_exec() {
    if chroot_status $chrootdir;then
        exec chroot $chrootdir $args
    else
        exec $CHROOT $chrootdir $args
    fi
}
# Kill all pid in container $1 with signal $2.
kill_chroot(){
    for chrootdir in /proc/*/root ;do
        pid=$(basename $(dirname $chrootdir))
        if [[ $(readlink -f $chrootdir) = $1 ]] && \
        [[ $pid =~ ^[0-9]+$ ]];then
            kill $2 $pid
        fi
    done
}
# stop chrootdir
chroot_halt(){
    [[ ! -d "$chrootdir" || "$chrootdir" == "/" ]] && return 1
    [ -z "$HALT" ] && source_profile
    [ -n "$HALT" ] && chroot "$chrootdir" $HALT
    kill_chroot "$chrootdir" $args
    kill_chroot "$chrootdir" -9
    mountpoint -q "$chrootdir" && umount -lr "$chrootdir"
}

usage(){
    cat <<EOF
Usage: ${0##*/} [init|start|login|shell|exec|list|status|halt|stop|kill|poweroff]
EOF
}

applet=$1
shift
chrootdir=$(readlink -f "$1")
shift
args=${@}

case $applet in
    init|start)
        chroot_init     ;;
    login|shell|exec)
        chroot_exec     ;;
    list)
        chroot_list     ;;
    status)
        chroot_status   ;;
    halt|stop|kill|poweroff)
	chroot_halt     ;;
    -h|help|--help)
        usage && exit 0 ;;
    *)
        usage && exit 1 ;;
esac