propagator/mkinitfs

#!/bin/sh -e

PROG=mkinitfs

Fatal()
{
    echo "$PROG: $*" >&2
    exit 1
}

TEMP=

exit_handler()
{
    local rc=$?
    trap - EXIT
    [ -z "$TEMP" ] || rm -f -- "$TEMP"
    [ $rc -eq 0 ] || rm -f -- "$OUT"
    exit $rc
}

[ -n "$1" ] || Fatal "Usage: mkinitfs outfile"
OUT="$1"; shift

trap exit_handler HUP PIPE INT TERM QUIT EXIT
TEMP=`mktemp -t mkinitfs.XXXXXXXXXX` || Fatal "Failed to create temporary file."

udevd="/lib/mkinitrd/udev/sbin/udevd"
[ -x "$udevd" ] && {
    udev_version="$($udevd --version 2>/dev/null)"
    printf '%s\n' "${udev_version:-105}" > udev_version
} || {
    Fatal "$udevd doesn't exists or not executable"
}

(

cat <<EOF
dir	/dev 		0755	0 0
dir	/image		0755	0 0
dir	/proc		0755	0 0
dir	/sys		0755	0 0
dir	/root		0755	0 0
dir	/tmp		0755	0 0
dir	/var		0755	0 0
dir	/var/lock	0755	0 0

dir	/etc		0755	0 0
dir	/etc/modprobe.d	0755	0 0

dir	/etc/terminfo	0755	0 0
dir	/etc/terminfo/l	0755	0 0
file	/etc/terminfo/l/linux	/lib/terminfo/l/linux	0644	0 0

dir	/etc/udev	0755	0 0

dir	/lib		0755	0 0
dir	/lib64		0755	0 0
dir	/lib/udev	0755	0 0
dir	/lib/udev/rules.d	0755	0 0
dir	/lib/modules	0755	0 0
dir	/lib/firmware	0755	0 0

dir	/bin		0755	0 0
file	/bin/sh		/lib/mkinitrd/klibc/bin/sh	0755	0 0
file	/bin/mount	/lib/mkinitrd/klibc/bin/mount	0755	0 0
file	/bin/umount	/lib/mkinitrd/klibc/bin/umount	0755	0 0
file	/bin/nfsmount	/lib/mkinitrd/klibc/bin/nfsmount	0755	0 0

dir	/sbin		0755	0 0
file	/sbin/modprobe	/lib/mkinitrd/module-init-tools/sbin/modprobe	0755	0 0

file	/init		init	0755	0 0
file	/.udev_version	udev_version	0644	0 0
EOF

find /lib/mkinitrd/klibc -xtype f -name klibc\*.so|\
    sed -e 's,^.\+/\([^\/]\+/[^\/]\+\)$,file\t/\1\t&\t0755\t0 0,g'
find /lib/mkinitrd/udev -type f|\
    sed -e 's,/lib/mkinitrd/udev,,' -e 's,^.\+$,file\t&\t/lib/mkinitrd/udev&\t0755\t0 0,g'
find /etc/udev/initramfs-rules.d/ -xtype f|\
    sed -e 's,^.\+rules\.d\(.\+\)$,file\t/lib/udev/rules.d\1\t&\t0644\t0 0,g'
find /etc/modprobe.d/ -type f|\
    sed -e 's,^.\+$,file\t&\t&\t0644\t0 0,g'
) | `pwd`/gencpio - > "$TEMP"

gzip -c < "$TEMP" > "$OUT"