#!/bin/sh

. /etc/default/rcS

CFGDIR="/etc/default/volatiles"
TMPROOT="/var/tmp"
COREDEF="00_core"

[ "${VERBOSE}" != "no" ] && echo "Populating volatile Filesystems."

create_file() {
	EXEC=" 
	touch \"$1\"; 
	chown ${TUSER}.${TGROUP} $1 || echo \"Failed to set owner -${TUSER}- for -$1-.\" >/dev/tty0 2>&1; 
	chmod ${TMODE} $1 || echo \"Failed to set mode -${TMODE}- for -$1-.\" >/dev/tty0 2>&1 " 

	test "$VOLATILE_ENABLE_CACHE" = yes && echo "$EXEC" >> /etc/volatile.cache

	[ -e "$1" ] && {
	  [ "${VERBOSE}" != "no" ] && echo "Target already exists. Skipping."
	} || {
	  eval $EXEC &
	}
}

mk_dir() {
	EXEC=" 
	mkdir -p \"$1\"; 
	chown ${TUSER}.${TGROUP} $1 || echo \"Failed to set owner -${TUSER}- for -$1-.\" >/dev/tty0 2>&1; 
	chmod ${TMODE} $1 || echo \"Failed to set mode -${TMODE}- for -$1-.\" >/dev/tty0 2>&1 "

	test "$VOLATILE_ENABLE_CACHE" = yes && echo "$EXEC" >> /etc/volatile.cache
	
	[ -e "$1" ] && {
	  [ "${VERBOSE}" != "no" ] && echo "Target already exists. Skipping."
	} || {
	  eval $EXEC &
	}
}

link_file() {
	EXEC="test -e \"$2\" -o -L $2 || ln -s \"$1\" \"$2\" >/dev/tty0 2>&1" 

	test "$VOLATILE_ENABLE_CACHE" = yes && echo "	$EXEC" >> /etc/volatile.cache
	
	[ -e "$2" ] && {
	  echo "Cannot create link over existing -${TNAME}-." >&2
	} || {
	  eval $EXEC &
	}
}

check_requirements() {

  cleanup() {
    rm "${TMP_INTERMED}"
    rm "${TMP_DEFINED}"
    rm "${TMP_COMBINED}"
    }
    
  CFGFILE="$1"

  [ `basename "${CFGFILE}"` = "${COREDEF}" ] && return 0

  TMP_INTERMED="${TMPROOT}/tmp.$$"
  TMP_DEFINED="${TMPROOT}/tmpdefined.$$"
  TMP_COMBINED="${TMPROOT}/tmpcombined.$$"


  cat /etc/passwd | sed 's@\(^:\)*:.*@\1@' | sort | uniq > "${TMP_DEFINED}"
  cat ${CFGFILE} | grep -v "^#" | cut -d " " -f 2 > "${TMP_INTERMED}"
  cat "${TMP_DEFINED}" "${TMP_INTERMED}" | sort | uniq > "${TMP_COMBINED}"

  NR_DEFINED_USERS="`cat "${TMP_DEFINED}" | wc -l`"
  NR_COMBINED_USERS="`cat "${TMP_COMBINED}" | wc -l`"

  [ "${NR_DEFINED_USERS}" -ne "${NR_COMBINED_USERS}" ] && {
    echo "Undefined users:"
    diff "${TMP_DEFINED}" "${TMP_COMBINED}" | grep "^>"
    cleanup
    return 1
    }


  cat /etc/group | sed 's@\(^:\)*:.*@\1@' | sort | uniq > "${TMP_DEFINED}"
  cat ${CFGFILE} | grep -v "^#" | cut -d " " -f 3 > "${TMP_INTERMED}"
  cat "${TMP_DEFINED}" "${TMP_INTERMED}" | sort | uniq > "${TMP_COMBINED}"

  NR_DEFINED_GROUPS="`cat "${TMP_DEFINED}" | wc -l`"
  NR_COMBINED_GROUPS="`cat "${TMP_COMBINED}" | wc -l`"

  [ "${NR_DEFINED_GROUPS}" -ne "${NR_COMBINED_GROUPS}" ] && {
    echo "Undefined groups:"
    diff "${TMP_DEFINED}" "${TMP_COMBINED}" | grep "^>"
    cleanup
    return 1
    }

  # Add checks for required directories here

  cleanup
  return 0
  }

apply_cfgfile() {

  CFGFILE="$1"

  check_requirements "${CFGFILE}" || {
    echo "Skipping ${CFGFILE}"
    return 1
    }

  cat ${CFGFILE} | grep -v "^#" | \
  while read LINE; do

    eval `echo "$LINE" | sed -n "s/\(.*\)\ \(.*\) \(.*\)\ \(.*\)\ \(.*\)\ \(.*\)/TTYPE=\1 ; TUSER=\2; TGROUP=\3; TMODE=\4; TNAME=\5 TLTARGET=\6/p"`

    [ "${VERBOSE}" != "no" ] && echo "Checking for -${TNAME}-."


    [ "${TTYPE}" = "l" ] && {
      TSOURCE="$TLTARGET"
      [ -L "${TNAME}" ] || {
        [ "${VERBOSE}" != "no" ] && echo "Creating link -${TNAME}- pointing to -${TSOURCE}-."
        link_file "${TSOURCE}" "${TNAME}" &
        }
      continue
      }

    [ -L "${TNAME}" ] && {
      [ "${VERBOSE}" != "no" ] && echo "Found link."
      NEWNAME=`ls -l "${TNAME}" | sed -e 's/^.*-> \(.*\)$/\1/'`
      echo ${NEWNAME} | grep -v "^/" >/dev/null && {
        TNAME="`echo ${TNAME} | sed -e 's@\(.*\)/.*@\1@'`/${NEWNAME}"
        [ "${VERBOSE}" != "no" ] && echo "Converted relative linktarget to absolute path -${TNAME}-."
        } || {
        TNAME="${NEWNAME}"
        [ "${VERBOSE}" != "no" ] && echo "Using absolute link target -${TNAME}-."
        }
      }

    case "${TTYPE}" in
      "f")  [ "${VERBOSE}" != "no" ] && echo "Creating file -${TNAME}-."
            create_file "${TNAME}" &
	    ;;
      "d")  [ "${VERBOSE}" != "no" ] && echo "Creating directory -${TNAME}-."
            mk_dir "${TNAME}" &
	    # Add check to see if there's an entry in fstab to mount.
	    ;;
      *)    [ "${VERBOSE}" != "no" ] && echo "Invalid type -${TTYPE}-."
            continue
	    ;;
    esac


    done

  return 0

  }

if test -e /etc/volatile.cache -a "$VOLATILE_ENABLE_CACHE" = "yes" -a "x$1" != "xupdate"
then
	sh /etc/volatile.cache
else	
	rm -f /etc/volatile.cache
	for file in `ls -1 "${CFGDIR}" | sort`; do
		apply_cfgfile "${CFGDIR}/${file}"
	done
fi
