rpm2cpio shell script

README

You just need to save that to rpm2cpio.sh, make it executable, and then
run

	rpm2cpio rpm-4.1.1-1.7x.src.rpm | cpio -idv


Source: http://www.redhat.com/archives/rpm-list/2003-June/msg00367.html

rpm2cpio.sh

#!/bin/sh

pkg=$1
if [ "$pkg" = "" -o ! -e "$pkg" ]; then
    echo "no package supplied" 1>&2
   exit 1
fi

leadsize=96
o=`expr $leadsize + 8`
set `od -j $o -N 8 -t u1 $pkg`
il=`expr 256 \* \( 256 \* \( 256 \* $2 + $3 \) + $4 \) + $5`
dl=`expr 256 \* \( 256 \* \( 256 \* $6 + $7 \) + $8 \) + $9`

sigsize=`expr 8 + 16 \* $il + $dl`
o=`expr $o + $sigsize + \( 8 - \( $sigsize \% 8 \) \) \% 8 + 8`
set `od -j $o -N 8 -t u1 $pkg`
il=`expr 256 \* \( 256 \* \( 256 \* $2 + $3 \) + $4 \) + $5`
dl=`expr 256 \* \( 256 \* \( 256 \* $6 + $7 \) + $8 \) + $9`

hdrsize=`expr 8 + 16 \* $il + $dl`
o=`expr $o + $hdrsize`

dd if=$pkg ibs=$o skip=1 2>/dev/null | gunzip