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

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

poll_device() {
    device="$1"
    if [ "$2" -ge 0 ]; then
        seconds="$2"
    else
        seconds=5
    fi
    if [ "${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
}

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
}

default_mount_handler() {
    # resolve tag name to block device
    if [ "${root:0:5}" = 'UUID=' ] || [ "${root:0:6}" = 'LABEL=' ]; then
        device=$(blkid -l -t "$root" -o device)
        if [ -n "$device" ]; then
            root=$device
        fi
        unset device
    fi

    if [ ${root:0:5} != "/dev/" ] || ! poll_device "${root}" ${rootdelay}; then
        msg "Root device '${root}' doesn't exist. Attempting to create it."
        major=""
        minor=""
        if [ ${devtmpfs_mounted} -eq 0 -a ${root:0:5} = "/dev/" ]; then
            # It might be a block device (/dev/sda) -> /sys/class/block/sda/dev
            if [ -e /sys/class/block/${root:5}/dev ]; then
                IFS=':' read major minor < "/sys/class/block/${root:5}/dev"
                break
            fi
        # It might be a major/minor pair (8:1)
        elif [ "$root" != "${root/:}" ]; then
            major="$(echo ${root} | cut -d: -f1)"
            minor="$(echo ${root} | cut -d: -f2)"
            root="/dev/root"
        # It might be major/minor encoded as a single hex-number (lilo-style) (801)
        elif [ ${#root} -le 4 -a ${#root} -gt 2 -a -z "${root//[0-9a-fA-F]}" ]; then
            str_offset=$((${#root}-2))
            major=$((0x${root:0:${str_offset}}))
            minor=$((0x${root:${str_offset}}))
            root="/dev/root"
        fi
        if [ -n "${major}" -a -n "${minor}" ]; then
            msg "Creating root device ${root} with major ${major} and minor ${minor}."
            mknod ${root} b ${major} ${minor}
        else
            err "Unable to determine major/minor number of root device '${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
    fi
    # We didn't build filesystem support into busybox,
    # instead we use util-linux's blkid for best compatibility
    fstype=${rootfstype:-$(blkid -u filesystem -o value -s TYPE -p "$root")}
    if [ -z "$fstype" ]; then
        err "Unable to determine the file system type of ${root}:"
        echo "Either it contains no filesystem, an unknown filesystem,"
        echo "or more than one valid file system signature was found."
        echo
        echo "Try adding"
        echo "    rootfstype=your_filesystem_type"
        echo "to the kernel command line."
        echo
        echo "You are now being dropped into an emergency shell."
        launch_interactive_shell
        msg "Trying to continue (this will most likely fail) ..."
    fi
    mount ${fstype:+-t $fstype} -o ${rwopt:-ro}${rootflags:+,$rootflags} "$root" "$1"
}

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