#!/bin/bash

. ../.config

INITRAMFS=/tmp/$LIVEKITNAME-initramfs-$$

# copy file to initramfs tree, including
# all library dependencies (as shown by ldd)
# $1 = file to copy (full path)
copy_including_deps()
{
   # if source doesn't exist or target exists, do nothing
   if [ ! -e "$1" -o -e "$INITRAMFS"/"$1" ]; then
      return
   fi

   cp -R --parents "$1" "$INITRAMFS"
   if [ -L "$1" ]; then
      DIR="$(dirname "$1")"
      LNK="$(readlink "$1")"
      copy_including_deps "$(cd "$DIR"; realpath -s "$LNK")"
   fi

   ldd "$1" 2>/dev/null | sed -r "s/.*=>|[(].*//g" | sed -r "s/^\\s+|\\s+\$//" \
     | while read LIB; do
        copy_including_deps "$LIB"
     done

   shift
   if [ "$1" != "" ]; then
       copy_including_deps "$@"
   fi
}

rm -Rf $INITRAMFS
mkdir -p $INITRAMFS/{bin,dev,etc,lib,lib64,mnt,proc,root,run,sbin,sys,tmp,usr,var/log}

modprobe zram
copy_including_deps /dev/zram0

copy_including_deps /dev/console /dev/null /dev/fb0 /dev/zero
copy_including_deps /dev/ram /dev/systty /dev/fuse
copy_including_deps /dev/tty /dev/tty?
copy_including_deps /bin/bash /bin/mount /bin/mkdir
copy_including_deps /bin/ln /bin/cat /bin/ls /bin/free
copy_including_deps /sbin/blkid /sbin/swapon /sbin/mkswap /sbin/modprobe
copy_including_deps /bin/grep /bin/egrep /bin/cut /bin/tr
copy_including_deps /sbin/lsmod
copy_including_deps /sbin/fdisk

copy_including_deps /usr/bin/vi
copy_including_deps /usr/bin/strace

# TODO: add all comon filesystems which are NOT compiled in kernel already
copy_including_deps /$LMK/kernel/fs/squashfs
copy_including_deps /$LMK/kernel/drivers/staging/zram
copy_including_deps /$LMK/modules.*

depmod -b $INITRAMFS

echo "root::0:0::/root:/bin/bash" >$INITRAMFS/etc/passwd
touch $INITRAMFS/etc/{m,fs}tab

cp init $INITRAMFS/
chmod a+x $INITRAMFS/init

cd $INITRAMFS
find . -print | cpio -o -H newc 2>/dev/null | gzip -f --best >$INITRAMFS.img
echo $INITRAMFS.img