update_save_back

#!/bin/bash
#IFS=$'\0' #https://stackoverflow.com/questions/8677546/reading-null-delimited-strings-through-a-bash-loop
#IFS='' #https://stackoverflow.com/questions/6563979/how-to-use-null-0-as-the-delimiter-in-gnu-sort
#IFS='  '
#IFS=''
OUT="/tmp/Udate_save/"

mkdir -p "$OUT"
decode_id() {
  if [ -f "$OUT"'BLKIDOUT' ]; then
     DECODE_ID_RTN=`cat "$OUT"'BLKIDOUT'`
  else
    BLKIDOUT="$(blkid)"
    DECODE_ID_RTN="$(echo "$BLKIDOUT" | grep -m1 -E " LABEL=.${1}| UUID=.${1}" | cut -f1 -d: | cut -f3 -d/)" #is LABEL or UUID
    echo "$DECODE_ID_RTN" > "$OUT"'BLKIDOUT'
  fi
  echo "$DECODE_ID_RTN"
}

###################### Initial Parmaters ############

#ROOT_UUI="fab3b011-746f-448b-85a3-5f7fb7f8e7f6" #sdd4 (Toshiba)
ROOT_UUI="ebeda76b-c7e8-d201-a020-a46bc7e8d201" #sdd6


#ROOT_REL_PATH  #Variable not yet defined

decode_id "$ROOT_UUI"
SAVE_ROOT_DRV="$DECODE_ID_RTN"
ROOT_REL_PATH="/tahrsave"
SAVE_ROOT="/mnt/$SAVE_ROOT_DRV$ROOT_REL_PATH"
RW_ROOT=`readlink /initrd/pup_rw`

#taken from line 222 if initrd/init tahrpup and trimmed extensively

###################### Functions ############

save_dir_array(){ #Was bind_and_link_array in map_save
  local -n one=${1} # https://stackoverflow.com/questions/16461656/how-to-pass-array-as-an-argument-to-a-function-in-bash
  #declair -a one=$one1
  if [ $# -lt 2 ]; then
    SR="$SAVE_ROOT"
  else
    SR=$2
  fi
  one=${one[*]} #https://stackoverflow.com/questions/3348443/a-confusion-about-array-versus-array-in-the-context-of-a-bash-comple?utm_medium=organic&utm_source=google_rich_qa&utm_campaign=google_rich_qa
  one=${one#'('} #https://stackoverflow.com/questions/16623835/remove-a-fixed-prefix-suffix-from-a-string-in-bash?utm_medium=organic&utm_source=google_rich_qa&utm_campaign=google_rich_qa
  one=${one%')#'}
  echo "Ln 49 one=${one[@]}"
  IFS_OLD=$IFS
  IFS=$'\n'
  for a in ${one[@]}; do
     echo "LN#53 save_file $a"
     save_file "$a" "$SR"
  done
  IFS=IFS_OLD
}


save_dir_files(){ #Was bind_and_link_dir in map_save
  #local -n one=$1
  if [ $# -lt 2 ]; then
    SR="$SAVE_ROOT"
  else
    SR=$2
  fi
  one="$1"
  echo "LN#68 one=$one"
  [ ! `mountpoint -q "$one"` ] || return _
  mkdir -p "$SAVE_ROOT$one"
  DIRS2=( $( find $RW_ROOT$one -mindepth 1 -maxdepth 1 -print0 -name '*'  | removePrefix "$RW_ROOT" ) )#
  echo "LN#72 DIRS2=${DIRS2[@]}"
  save_dir_array DIRS2 $2
}
save_file(){ #Was bind_and_link in map_save
  f="$1"
  if [ $# -gt 1 ]; then
    SR="$2"
  else
    SR="$SAVE_ROOT"
  fi
  echo "LN#82 save_file $RW_ROOT$f"
  if [ -L "$f" ]; then #Don't copy if the link links back to the save file
    [[ `readlink $f` =~ ^$SAVE_ROOT ]] && return _ #https://stackoverflow.com/questions/4132510/how-to-test-that-a-variable-starts-with-a-string-in-bash
  elif [ -d "$RW_ROOT$f" ]; then
    save_dir_files "$f"
    return _
  fi
  #Copy only if knewer.
  cp -a -u "$RW_ROOT$f" "$SR$f"  #we reversed the from to direction in copy from map_save
}
#echo $(dirname $(readlink -f "$fname")) # get directory name https://stackoverflow.com/questions/6121091/get-file-directory-path-from-file-path
######################### MAIN ###########################
declare -a  dirs_to_link_and_bind=\
( "/etc" "/DEBIAN" "/bin" "/etc" "/lib" "/lib64" \
   "/opt" "/root" "/sbin" "/var" "/usr" "/var" \
)

for dir in ${dirs_to_link_and_bind[@]}; do
  mkdir -p $SAVE_ROOT$dir
  save_dir_files $dir
done