Ubuntu-fr

#!/bin/bash

# run as root?
if [[ $EUID -ne 0 ]]; then
   echo "This script must be run as root" 
   exit 1
fi

# one argument?
if [[ $# -ne 1 ]]; then
    echo "Usage: ./my_script {path_iso}"
    exit
fi

# file exists?
if [[ ! -e $1 ]]; then
    echo "File $1 not found"
    exit
fi

# install utilities
apt install -y squashfs-tools schroot genisoimage syslinux-utils

# create all directories and copy files on it
mkdir -p ~/livecd/{iso,squashfs}
cd ~/livecd || exit
mount -o loop "$1" /mnt
cp -av /mnt/. iso
umount /mnt
mount -t squashfs -o loop iso/casper/filesystem.squashfs /mnt
cp -av /mnt/. squashfs
umount /mnt

# add endless OS repo
echo "deb https://deb.endlessos.org/debian master endless" | tee -a squashfs/etc/apt/sources.list

# add modif for sources.list and prefs of apt
echo -e "# don't use packages of endless OS
Package: *
Pin: origin "https://deb.endlessos.org/debian/"
Pin-Priority: -1

# only use linux-{image,headers} packages of endless OS
Package: linux-{image-generic,base,headers-generic}
Pin: origin "https://deb.endlessos.org/debian/"
Pin-Priority: 1000" > squashfs/etc/apt/preferences.d/eos.pref


cp /etc/resolv.conf squashfs/etc/


mount --bind /dev/ squashfs/dev
# let's go deeper
chroot squashfs
mount -t proc none /proc
mount -t sysfs none /sys
mount -t devpts none /dev/pts

export HOME=/root
export LC_ALL=C

# install linux kernel from endless OS thanks to apt preferences set before
wget -q https://deb.endlessos.org/keys/eos-pub-archive-key.asc -O- | apt-key add -
apt update
# install kernel of endless OS
apt install -y linux-base linux-image-generic linux-headers-generic

# it's time to clean
apt clean
rm -rf /tmp/* ~/.bash_history
rm -r /var/crash/*
rm /etc/resolv.conf

# unmount and exit the chroot
umount /proc || umount -lf /proc
umount /sys
umount /dev/pts
umount /dev || echo "W: Failed to unmount /dev"
exit

# in case they are needed, for debug purpose
mv iso/casper/{initrd,vmlinuz} .

# insert new kernel
cp squashfs/boot/initrd.img-* iso/casper/initrd # .gz useful?
cp squashfs/boot/vmlinuz-* iso/casper/vmlinuz

# renew squashfs
chmod a+w iso/casper/filesystem.manifest
chroot squashfs dpkg-query -W --showformat='${Package}  ${Version}\n' > iso/casper/filesystem.manifest
chmod go-w iso/casper/filesystem.manifest

# update squashfs
rm iso/casper/filesystem.squashfs
mksquashfs squashfs iso/casper/filesystem.squashfs

# update filesystem.size
printf $(du -sx --block-size=1 squashfs | cut -f1) > iso/casper/filesystem.size

# update md5sums
cd iso
rm md5sum.txt
find -type f -print0 | xargs -0 md5sum | grep -v isolinux/boot.cat | tee md5sum.txt

# create iso
#from help.ubuntu
# mkisofs -D -r -V "custom" -cache-inodes -J -l -b isolinux/isolinux.bin -c isolinux/boot.cat -no-emul-boot -boot-load-size 4 -boot-info-table -o ../Custom.iso .
mkisofs -U -A "Custom" -V "Custom" -volset "Custom" -J -joliet-long -r -v -T -o ../Custom.iso -b isolinux/isolinux.bin -c isolinux/boot.cat -no-emul-boot -boot-load-size 4 -boot-info-table -eltorito-alt-boot -e boot/grub/efi.img -no-emul-boot .
#usb compatible
cd ..
isohybrid -u Custom.iso

### old script

# cd iso
# bash -c "find . -path ./isolinux -prune -o -type f -not -name md5sum.txt -print0 | xargs -0 md5sum | tee md5sum.txt"

# # reconstruct the iso file
# mkisofs -U -A "Custom" -V "Custom" -volset "Custom" -J -joliet-long -r -v -T -o ../Custom.iso -b isolinux/isolinux.bin -c isolinux/boot.cat -no-emul-boot -boot-load-size 4 -boot-info-table -eltorito-alt-boot -e boot/grub/efi.img -no-emul-boot .
# cd ..
# isohybrid -u Custom.iso
# cd ~
# rm -r ~/livecd
# echo "Finished"

Package: *
Pin: origin "deb.endlessos.org"
Pin-Priority: 1

Package: linux-image-generic, linux-headers-generic
Pin: origin "deb.endlessos.org"
Pin-Priority: 1000