Initrd image for busybox

Here is a script to create initrd image for busybox:



#!/bin/bash



# 2006 by Marco Amrein, released into Public Domain, except the patch lines for

# .config, which are probably GPL'd and thus (C).



set -euv



BB=busybox-1.1.0



apt-get install wget gcc e2fsprogs || true



[ -f $BB.tar.gz ] || wget http://www.busybox.net/downloads/$BB.tar.gz || exit 1

[ -d $BB ] || tar xvfz $BB.tar.gz || exit 1



if [ ! -x $BB/busybox ] ; then

        cd $BB

        make clean

        make allyesconfig

 patch <<__endconfpatch__ span="">

--- .config.orig 2006-02-11 18:03:59.000000000 +0100

+++ .config 2006-02-11 18:05:08.000000000 +0100

@@ -24,5 +24,5 @@

 # Build Options

 #

-# CONFIG_STATIC is not set

+CONFIG_STATIC=y

 CONFIG_LFS=y

 # USING_CROSS_COMPILER is not set

@@ -511,9 +511,9 @@

 # Shells

 #

-# CONFIG_FEATURE_SH_IS_ASH is not set

+CONFIG_FEATURE_SH_IS_ASH=y

 # CONFIG_FEATURE_SH_IS_HUSH is not set

 # CONFIG_FEATURE_SH_IS_LASH is not set

 # CONFIG_FEATURE_SH_IS_MSH is not set

-CONFIG_FEATURE_SH_IS_NONE=y

+# CONFIG_FEATURE_SH_IS_NONE is not set

 CONFIG_ASH=y

 

__ENDCONFPATCH__

 make oldconfig

        make

        cd ..

fi



dd if=/dev/zero of=bb-initrd.img count=1 bs=12M

mke2fs -F -i 1024 bb-initrd.img



mkdir -p bb-initrd

mount -o loop bb-initrd.img bb-initrd



cp -a /dev/.static/dev bb-initrd

mkdir bb-initrd/proc

mkdir bb-initrd/bin

mkdir bb-initrd/sbin

mkdir bb-initrd/tmp

chmod 1777 bb-initrd/tmp

mkdir bb-initrd/mnt

mkdir bb-initrd/etc

mkdir bb-initrd/etc/init.d

touch bb-initrd/etc/mtab



cp -a $BB/busybox bb-initrd/bin/



mount -t proc proc bb-initrd/proc

chroot bb-initrd /bin/busybox --install -s

umount bb-initrd/proc



cat >bb-initrd/etc/init.d/rcS <

#! /bin/sh

/bin/mount -t proc proc proc

#echo go for it!

/bin/ash

EOFrcS



chmod 755 bb-initrd/etc/init.d/rcS



umount bb-initrd



gzip -9 bb-initrd.img



echo 'We are done...'



Thanks Marco Amrein!