#! /bin/sh

set -e

# Gracefully exit if ltsp_chroot file is not present
test -f /etc/ltsp_chroot || exit 0

bind_mounts () {
    # set defaults
    test -z "$tmpfs_dir" && tmpfs_dir=/var/lib/ltsp-client-setup
    mount -t tmpfs -o mode=0755 tmpfs $tmpfs_dir
    bind_missing=""
    # preserve directory structure
    for d in $rw_dirs ; do
        if [ -d "$d" ]; then
            cd $tmpfs_dir
            tar --no-recursion -cpf - $(find $d -type d 2> /dev/null) 2> /dev/null | tar xpf -
            mount --bind $tmpfs_dir/$d $d
        else
            bind_missing="$bind_missing $d"
        fi
    done
    # copy contents into tmpfs
    for d in $copy_dirs $temp_copy_dirs; do
        if [ -d "$d" ]; then
            cd $tmpfs_dir
            tar -cpf - $d 2> /dev/null | tar xpf -
            mount --bind $tmpfs_dir/$d $d
        else
            bind_missing="$bind_missing $d"
        fi
    done
    # mount one file on top of another
    for f in $bindfiles ; do
        if [ -e "$f" ]; then
            mkdir -p "$(dirname $tmpfs_dir/$f)"
            cp $f $tmpfs_dir/$f
            mount --bind $tmpfs_dir/$f $f
        else
            bind_missing="$bind_missing $f"
        fi
    done
    if [ -n "$bind_missing" ]; then
        echo "note: ltsp: missing files or directories for bind mounting: $bind_missing"
    fi
}

bind_unmounts() {
    for dir in $temp_copy_dirs; do
        umount $dir
        rm -rf $tmpfs_dir/${dir#/}
    done
}

# tmpfs/bind directories that get mounted with only directory structure
# preserved

rw_dirs="/var/lib/xkb /var/log /var/spool /var/tmp /tmp /etc/console-setup /var/lib/pulse /var/lib/dbus /var/cache/hald /var/cache/ltsp /var/lib/urandom"

# tmpfs/bind directories that get mounted with directory structure and data
# copied
copy_dirs="/root /home /var/cache/ltsp-localapps /etc/rsyslog.d /etc/cups /media /etc/cron.d /etc/udev/rules.d"

# tmpfs/bind files that mounted on top of other files
bindfiles="/etc/network/interfaces /etc/hostname /etc/hosts /etc/syslog.conf /etc/fstab /etc/resolv.conf /etc/X11/xorg.conf /etc/passwd /etc/group /etc/localtime" 

. /usr/share/ltsp/ltsp-init-common

# override variables if configured via lts.conf or ltsp_config
[ -n "$LTSP_RW_DIRS" ] && rw_dirs="$LTSP_RW_DIRS"
[ -n "$LTSP_RW_DIRS_EXTRA" ] && rw_dirs="$rw_dirs $LTSP_RW_DIRS_EXTRA"
[ -n "$LTSP_COPY_DIRS" ] && copy_dirs="$LTSP_COPY_DIRS"
[ -n "$LTSP_COPY_DIRS_EXTRA" ] && copy_dirs="$rw_dirs $LTSP_COPY_DIRS_EXTRA"
[ -n "$LTSP_BINDFILES" ] && bindfiles="$LTSP_BINDFILES"
[ -n "$LTSP_BINDFILES_EXTRA" ] && bindfiles="$rw_dirs $LTSP_BINDFILES_EXTRA"

bind_mounts