#!/bin/bash
#
# syntax: mkbootp [nobuild] [startpkg]

# version numbers of packages to use
libc="glibc-2.3.2-r9"
#busybox="busybox-0.60.3-r1"
busybox="busybox-1.0.0_pre20040726"
util="util-linux-2.12-r4"
#kernel="vanilla-sources-2.4.26"
kernel="alpha-sources-2.4.21-r10"
e2fs="e2fsprogs-1.35"
reiserfs="reiserfsprogs-3.6.17"
xfs="xfsprogs-2.6.3"

instdir=`pwd`
target=${instdir}/rootdisk

# should double-check libc version with what is currently installed.

if [[ $1 == nobuild ]]; then
    ebuild() { true; }
    shift
fi

if [[ -z $1 ]]; then 
    echo Create clean install target
    rm -rf initrd* ${target}
    mkdir ${target}
    /bin/tar -C skel -cf - . --exclude CVS | /bin/tar -C ${target} -xvf -
else
    start=$1
fi

# override some /etc/make.conf settings so that what we build here will
# work on as many alpha boxes as possible
export CHOST="alpha-unknown-linux-gnu"
export CFLAGS="-mcpu=ev4 -O3 -pipe"
export CXXFLAGS="$CFLAGS"
export USE="-* build bootstrap"

# This is for the sake of finding ebuilds below
eval $(grep ^PORTDIR= /etc/make.conf)

main() {
    declare pkg

    for pkg in e2fs xfs reiser libc busybox util kernel; do
        [[ -n ${start} && ${start} != ${pkg} ]] && continue
        echo "--- Build ${pkg} ---"
        ${pkg} || exit 1
        unset start
    done
}

e2fs() {
    ebuild ${PORTDIR}/sys-fs/e2fsprogs/${e2fs}.ebuild clean compile install || return 1
    cp -av /var/tmp/portage/${e2fs}/image/lib/*     ${target}/lib/ || return 1
    cp -av /var/tmp/portage/${e2fs}/image/bin/*     ${target}/bin/ || return 1
    cp -av /var/tmp/portage/${e2fs}/image/sbin/*    ${target}/sbin/ || return 1
}

xfs() {
    ebuild ${PORTDIR}/sys-fs/xfsprogs/${xfs}.ebuild clean compile install || return 1
    cp -av /var/tmp/portage/${xfs}/image/lib/*     ${target}/lib/ || return 1
    cp -av /var/tmp/portage/${xfs}/image/bin/*     ${target}/bin/ || return 1
    cp -av /var/tmp/portage/${xfs}/image/sbin/*    ${target}/sbin/ || return 1
}

reiser() {
    ebuild ${PORTDIR}/sys-fs/reiserfsprogs/${reiserfs}.ebuild clean compile install || return 1
    cp -av /var/tmp/portage/${reiserfs}/image/sbin/*    ${target}/sbin/ || return 1
}

libc() {
    ebuild ${PORTDIR}/sys-libs/glibc/${libc}.ebuild clean compile install || return 1
    cp -av /var/tmp/portage/${libc}/image/lib/libc.so.*     ${target}/lib/ || return 1
    cp -av /var/tmp/portage/${libc}/image/lib/ld-linux.so.* ${target}/lib/ || return 1
}

util() {
    ebuild ${PORTDIR}/sys-apps/util-linux/${util}.ebuild clean compile install || return 1
    cp -av /var/tmp/portage/${util}/image/sbin/fdisk ${target}/bin/ || return 1
}

busybox() {
    #ebuild ${PORTDIR}/sys-apps/busybox/${busybox}.ebuild clean unpack || return 1
    #cp -v config-${busybox} /var/tmp/portage/${busybox}/work/*/Config.h || return 1
    ebuild ${PORTDIR}/sys-apps/busybox/${busybox}.ebuild clean compile install || return 1
    cp -av /var/tmp/portage/${busybox}/image/bin/busybox ${target}/bin/ || return 1
    sed "s:^:${target}:" /var/tmp/portage/${busybox}/work/*/busybox.links \
        | xargs -n1 ln -svfn /bin/busybox
}

kernel() {
    ebuild ${PORTDIR}/sys-kernel/${kernel%%-[0-9]*}/${kernel}.ebuild clean install || return 1
    linuxsrc=`echo "/var/tmp/portage/${kernel}/image/usr/src/linux"*`
    make -C ${linuxsrc} mrproper || return 1
    cp config-${kernel} ${linuxsrc}/.config || return 1
    #yes '' |
    make -C ${linuxsrc} oldconfig dep || return 1
    # Only uncomment if you want to use kernel modules -- not really supported
    #make -C ${linuxsrc} modules modules_install INSTALL_MOD_PATH="${target}"

    size=$(( $(du -s ${target} | cut -f1) * 11 / 10 ))
    echo Building root disk of ${size}k
    dd if=/dev/zero of=initrd.img bs=1k count=${size} || return 1
    mke2fs -F initrd.img || return 1
    mkdir -p initrd || return 1
    mount initrd.img initrd -o loop || return 1
    cp -a ${target}/* initrd || return 1
    umount initrd || return 1
    gzip -9 initrd.img || return 1

    make -C ${linuxsrc} vmlinux bootpfile \
        INITRD="${instdir}/initrd.img.gz" \
        HPATH="${linuxsrc}/include" || return 1

    cp ${linuxsrc}/arch/alpha/boot/bootpfile .
    echo "Your bootp/tftp file is complete:"
    ls -l bootpfile
}

main