# This file contains common functions used in init and in hooks

msg () {
    [ "${quiet}" != "y" ] && echo $@
}
err () {
    echo "ERROR: $@"
}

poll_device() {
    local device=$1 seconds=${2//[!0-9]}

    [ -z "$seconds" ] && seconds=5

    [ -b "$device" ] && return 0

    if [ "$udevd_running" -eq 1 ]; then
        msg "Waiting $seconds seconds for device $device ..."
        while [ ! -b "$device" -a "$seconds" -gt 0 ]; do
            sleep 1
            seconds=$(( $seconds - 1 ))
        done
    fi

    [ -b "$device" ]
}

launch_interactive_shell() {
    export PS1='[ramfs \W]\$ '
    [ "$1" = "--exec" ] && exec sh -i
    sh -i
}

major_minor_to_device() {
    local dev

    [ -e "/sys/dev/block/$1:$2" ] || return 1

    if dev=$(readlink -f "/sys/dev/block/$1:$2" 2>/dev/null); then
        echo "/dev/${dev##*/}"
        return 0
    fi

    return 1
}

parse_cmdline() {
    local w in_quotes lhs rhs
    in_quotes=0
    for w in $(cat /proc/cmdline); do
        if [ ${in_quotes} -eq 0 ]; then
            case "${w}" in
                \#*) break ;; # ignore everything after a # in the commandline
                # The kernel passes those to init on its own
                [0123456Ss]) ;;
                single) ;;
                rw|ro) rwopt="$w" ;;
                # only export stuff that does work with ash :)
                =*) ;;
                *=*) rhs=${w#*=}
                    lhs=${w%%=*}
                    lhs=${lhs//[-.]/_}
                    if [ '"' = "${rhs:0:1}" ]; then
                        if [ "${rhs:$((${#rhs}-1))}" = '"' ]; then
                            rhs="${rhs:1:$((${#rhs}-2))}"
                        else
                            rhs="${rhs:1}"
                            in_quotes=1
                            continue
                        fi
                    fi
                    [ "$lhs" = "${lhs//[^0-9a-zA-Z]}" ] && [ "$lhs" = "${lhs#[0-9]}" ] && eval ${lhs}=\${rhs}
                    ;;
                *)  lhs=${w//[-.]/_}
                    [ "$lhs" = "${lhs//[^0-9a-zA-Z]}" ] && [ "$lhs" = "${lhs#[0-9]}" ] && eval ${lhs}=y
                    ;;
            esac
        else
            if [ '"' = "${w:$((${#w}-1))}" ]; then
                rhs="${rhs} ${w%\"}"
                in_quotes=0
                [ "$lhs" = "${lhs//[^0-9a-zA-Z]}" ] && [ "$lhs" = "${lhs#[0-9]}" ] && eval ${lhs}=\${rhs}
            else
                rhs="${rhs} ${w}"
            fi
        fi
    done
}

resolve_device() {
    local major minor dev device=$1

    case $device in
        # resolve tag name to block device
        UUID=*|LABEL=*)
            dev=$(blkid -lt "$device" -o device)
            [ -n "$device" ] && device=$dev
            ;;
    esac

    case $device in
        /dev/*)
            if poll_device "$device" "$rootdelay"; then
                echo "$device"
                return 0
            fi

            # block device, e.g. (/dev/sda1) -> /sys/class/block/sda1/dev
            if [ -e /sys/class/block/${device:5}/dev ]; then
                IFS=':' read major minor < "/sys/class/block/${device:5}/dev"
            fi
            ;;
        [0-9a-fA-F][0-9a-fA-F][0-9a-fA-F]|[0-9a-fA-F][0-9a-fA-F][0-9a-fA-F][0-9a-fA-F])
            # hex encoded major/minor, such as from LILO
            major=$(( 0x0$device >> 8 ))
            minor=$(( 0x0$device & 0xff ))
            ;;
        0x[0-9a-fA-F][0-9a-fA-F]*)
            major=$(( $device >> 8 ))
            minor=$(( $device & 0xff ))
            ;;
    esac

    if [ -n "$major" -a -n "$minor" ]; then
        device=$(major_minor_to_device "$major" "$minor" || echo '/dev/root')

        if [ ! -b "$device" ]; then
            msg "Creating device node with major $major and minor $minor." >&2
            mknod "$device" b "$major" "$minor"
        fi
        echo "$device"
        return 0
    fi

    return 1
}

default_mount_handler() {
    local rootdev

    if ! rootdev=$(resolve_device "$root"); then
        err "Unable to determine major/minor number of root device '$root'."
        echo "You are being dropped to a recovery shell"
        echo "    Type 'exit' to try and continue booting"
        launch_interactive_shell
        msg "Trying to continue (this will most likely fail) ..."
    fi

    if ! mount ${fstype:+-t $fstype} -o ${rwopt:-ro}${rootflags:+,$rootflags} "$rootdev" "$1"; then
        echo "You are now being dropped into an emergency shell."
        launch_interactive_shell
        msg "Trying to continue (this will most likely fail) ..."
    fi
}

# vim: set ft=sh ts=4 sw=4 et: