initrd/init:search_func() LN# 742-783 (tahrpup)

# LN# 742-783 of /initrd/init (tahrpup) - https://www.pearltrees.com/s243a/initrd-init/id19535893/item224275421
# LN# 802-843 of https://github.com/puppylinux-woof-CE/woof-CE/blob/c96d661c2232caef1d69c693de673fb0e54796f8/initrd-progs/0initrd/init#L802 (13 Mar 2018)
search_func() {
 [ "$PDEBUG" -a "$LOOK_SAVE" ] && echo "3: filename=${PSUBDIR}/${DISTRO_FILE_PREFIX}save"
 [ "$PDEBUG" -a "$LOOK_PUP" ] && echo "3: PSUBDIR=$PSUBDIR P_BP_FN=$P_BP_FN P_DEF_FN=$P_DEF_FN"
 echo "HAVE_PARTS='${HAVE_PARTS}'" #debug
 if [ "${1}" ];then
  echo "param='${1}'" #debug
  TRY_PARTS_FIRST="$(echo "$HAVE_PARTS" | grep -E "${1}")"
  TRY_PARTS_LAST="$(echo "$HAVE_PARTS" | grep -Ev "${1}")"
  TRY_PARTS="$TRY_PARTS_FIRST
$TRY_PARTS_LAST"
 else
  TRY_PARTS="$HAVE_PARTS"
 fi
 echo "TRY_PARTS='${TRY_PARTS}'" #debug
 [ "$TRY_PARTS" ] || return
 for ONETRY in $TRY_PARTS;do
  ONE_PART="$(echo -n "$ONETRY" | cut -f 1 -d '|')"
  [ "$PDEBUG" ] && echo "4: ONE_PART=$ONE_PART"
  ensure_mounted "$ONE_PART" "/mnt/pdrv"
  if [ "$ONE_MP" ];then
   if [ "$LOOK_SAVE" -a "$SAVEPART" = "" ];then
    set_fs_linux "$ONE_FS"
    find_save_file "$ONE_MP" "$ONE_PART" "$ONE_FS"
    if [ "$PUP_SAVES" ];then
     SAVEPART="$ONE_PART"
     [ "$PDEBUG" ] && echo "5: ONE_PART=$ONE_PART filename=${PSUBDIR}/${DISTRO_FILE_PREFIX}save"
    fi
   fi
   if [ "$LOOK_PUP" ];then
    find_drv_file "$P_BP_FN" "$P_DEF_FN"
    if [ "$ONE_FN" ];then
     PDRV="$ONE_PART,$ONE_FS,$ONE_FN"
     P_MP="$ONE_MP"
     P_PART="$ONE_PART"
     [ "$PDEBUG" ] && echo "5: ONE_PART=$ONE_PART PSUBDIR=$PSUBDIR P_BP_FN=$P_BP_FN P_DEF_FN=$P_DEF_FN"
     break;
    fi
   fi
   umount $ONE_MP
  fi
 done
}