#!/bin/sh
# Filename:      sh-lib
# Purpose:       Shellscript library
# Authors:       grml-team (grml.org), (c) Michael Gebetsroither <gebi@grml.org>
# Bug-Reports:   see http://grml.org/bugs/
# License:       This file is licensed under the GPL v2.
# Latest change: Mon May 02 00:17:44 CEST 2005 [gebi]
################################################################################


VERBOSE__=0
VERBOSE_TMP__=0

# FIXME maybe PROG_PATH__ for better error reporting?
PROG_NAME__=""    # initialised within init section

# directory for init scripts
INITD_DIR__="/etc/init.d/"

# >= level and the function will print the message
EPRINT__=1    # eprint (error print)
EEPRINT__=2   # 2print (intern error print)
DPRINT__=3    # dprint (debug print)

EXIT_FUNCTION__="_syslog"    # function to call upon die (can be set by user)

SYSLOG__="YES"

CMD_LINE__=""   # /proc/cmdline

LANG__="$LANG"
LC_ALL__="$LC_ALL"


# CONFIG FUNCTIONS  {{{

function setProgName  { PROG_NAME__="$1"; }

function setExitFunction  { EXIT_FUNCTION__="$1"; }

function disableSyslog  { SYSLOG__="NO";  }
function enableSyslog   { SYSLOG__="YES"; }

function saveLang { LANG__="$LANG"; LC_ALL__="$LC_ALL"; }
function restoreLang { LANG="$LANG__"; LC_ALL="$LC_ALL__"; }
function setCLang { saveLang; LANG="C"; LC_ALL="C"; }
# }}}


# DEBUG FRAMEWORK  {{{

function setVerbose     { VERBOSE__=${1:-1}; }
function unsetVerbose   { VERBOSE_TMP__=$VERBOSE__; VERBOSE__=0; }
function restoreVerbose { VERBOSE__=$VERBOSE_TMP__; }
function getVerbose     { echo "$VERBOSE__"; }

function setDebug       { setVerbose "$DPRINT__"; }
function unsetDebug     { restoreVerbose; }

function setExitFunction    { EXIT_FUNCTION__="$1"; }
function resetExitFunction  { EXIT_FUNCTION__="_syslog"; }
# }}}


# ERROR REPORTING FUNCTIONS  {{{

# default print backend (there may be other functions)
function vprint
{
  local level_="$1"
  local type_="$2"
  local message_="$3"
  
  if [ $VERBOSE__ -ge $level_ -a -n "$message_" ]; then
    echo -n "$type_" >&2
    echo "$message_" >&2
  fi
}

# print error output
function eprint
{
  # FIXME vprint should be a var, because we want to call user-defined functions
  # global var (there should be a syslog, and vprint + syslog function)
  vprint $EPRINT__ "Error - " "$1"
}

# should be used for intern silentExecutes
function eeprint
{
  vprint $EEPRINT__ "  Error2 - " "$1"
}

# print debug output (function intern errors)
function dprint
{
  vprint $DPRINT__ "Debug - " "$1"
}

# for program notice messages
function notice
{
  vprint $EPRINT__ "Notice - " "$1"
}

function die
{
  local error_message_="$1"   # print this error message
  local exit_code_="$2"  # command exited with this exit code

  echo -n "PANIC: $error_message_" >&2
  if [ -n "$2" ]; then
    echo "; ret($exit_code_)" >&2
  else
    echo >&2
  fi

  if [ -n "$EXIT_FUNCTION__" ]; then
    $EXIT_FUNCTION__ "$error_message_" "$exit_code_" >&2
  fi
  kill $$
}

function warn
{
  local error_message_="$1"   # print this error message
  local exit_code_="$2"  # command exits with this exit code

  echo -n "WARN: $error_message_" >&2
  if [ -n "$exit_code_" ]; then
    echo "; ret($exit_code_)" >&2
  else
    echo >&2
  fi
}

function _syslog
{
  local message_="$1"   # error message
  local exit_code_="$2"

  if [ "$SYSLOG__" = "YES" ]; then
    if [ -n "$exit_code_" ]; then
      logger -p user.alert -t "$PROG_NAME__" -i "$message_ ret($exit_code_)" >&2
    else
      logger -p user.alert -t "$PROG_NAME__" -i "$message_" >&2
    fi
  fi
}

function syslog
{
  local message_="$1"   # error message
  local exit_code_="$2"
  
  if [ -n "$exit_code_" ]; then
    logger -p user.alert -t "$PROG_NAME__" -i "$message_ ret($exit_code_)" >&2
  else
    logger -p user.alert -t "$PROG_NAME__" -i "$message_" >&2
  fi
}

function warnLog
{
  local error_message_="$1"   # print this error message
  local exit_code_="$2"  # command exits with this exit code

  warn "$error_message_" "$exit_code_"
  syslog "$error_message_" "$exit_code_"
}
# }}}


###
#
# CORE FUNCTIONS
#
###

# i don't want to write exit status controle stuff every time
function execute
{
  local to_exec_="$1"   # command to execute
  local error_function_=${2:-"eprint"}    # function to call on error
  local message_="$3"   # user supplied error message

  local ret_=''

  eval "$to_exec_"
  ret_=$?

  if [ $ret_ -eq 127 ]; then
    syslog "problems executing ( $to_exec_ )" $ret_
  fi
  if [ $ret_ -ne 0 ]; then
    if [ -z "$message_" ]; then
      $error_function_ "problems executing ( $to_exec_ )" "$ret_"
    else
      $error_function_ "$message_" "$ret_"
    fi
  fi
  dprint "exec-$error_function_: ( $to_exec_ ) ret($ret_)"
  return $ret_
}

function silentExecute
{
  unsetVerbose
  execute "$@"
  local ret_=$?
  restoreVerbose
  return $ret_
}


###
#
# TEST FUNCTIONS
#
###

# if the file DOES exist, everything is fine
function isExistent
{
  local file_to_test_="$1"    # file to test
  local error_function_=${2:-"eprint"}    # function to call on error
  local message_="$3"    # user supplied error message

  if [ ! -e "$file_to_test_" ]; then
    if [ -z "$message_" ]; then
      $error_function_ "file does not exist \"$file_to_test_\"" 66
    else
      $error_function_ "$message_"
    fi
    return 1
  fi
  dprint "isExistent(): file \"$1\" does exist => ready to go"
  return 0
}

function isNotExistent
{
  local file_to_test_="$1"    # file to test
  local error_function_=${2:-"eprint"}    # function to call on error
  local message_="$3"    # user supplied error message

  if [ -e "$file_to_test_" ]; then
    if [ -z "$message_" ]; then
      $error_function_ "file does allready exist \"$file_to_test_\"" 67
    else
      $error_function_ "$message_"
    fi
    return 1
  fi
  dprint "isNotExistent(): file \"$1\" does not exist => ready to go"
  return 0
}


function checkUser
{
  local to_check_="$1"    # username to check against running process
  local error_function_=${2:-"eprint"}    # function to call on error
  local message_="$3"    # user supplied error message

  local user_=''

  user_=`id -un`
  if [ $user_ != "$to_check_" ]; then
    if [ -z "$message_" ]; then
      $error_function_ "username \"$user_\" is not \"$to_check_\"" 77 $exit_function_
    else
      $error_function_ "$message_"
    fi
    return 1
  else
    dprint "checkUser(): accepted, username matches \"$to_check_\""
    return 0
  fi
}

function checkId
{
  local to_check_="$1"    # user-id to check against running process
  local error_function_=${2:-"eprint"}    # function to call on error
  local message_="$3"    # user supplied error message

  local user_id_=''

  user_id_=`id -u`
  if [ $user_id_ != "$to_check_" ]; then
    if [ -z "$message_" ]; then
      $error_function_ "UID \"$user_id_\" is not \"$to_check_\"" 77
    else
      $error_function_ "$message_"
    fi
    return 1
  else
    dprint "checkId(): accepted, UID matches \"$to_check_\""
    return 0
  fi
}

function checkRoot
{
  checkId 0 "$1" "$2"
}


function runsFromHd
{
  if [ -e "/etc/grml_cd" ]; then
    dprint "runsFromHd(): grml is on CD"
    return 1
  else
    dprint "runsFromHd(): grml is on HD"
    return 0
  fi
}

function runsFromCd
{
  if [ -e "/etc/grml_cd" ]; then
    dprint "runsFromCd(): grml is on CD"
    return 0
  else
    dprint "runsFromCd(): grml is on HD"
    return 1
  fi
}


# secure input from console
function secureInput
{
  local to_secure_="$1"
  
  local secured_=''

  secured_=`echo -n "$to_secure_" |tr -c '[:alnum:]/.\-,\(\)' '_'`
  dprint "secureInput(): \"$to_secure_\" => \"$secured_\""
  echo "$secured_"
}


# convert all possible path formats to absolute paths
function relToAbs
{
  local relpath_="$1"
  local abspath_=''

  abspath_="`readlink -f \"$relpath_\"`" || \
    warn "relToAbs(): Problems getting absolute path" "$?" || return 1
  dprint "relToAbs(): \"$relpath_\" => \"$abspath_\""
  echo "$abspath_"
}

# Simple shell grep
function stringInFile
{
  local to_test_="$1"   # matching pattern
  local source_="$2"    # source-file to grep

  if [ ! -e "$source_" ]; then
    eprint "stringInFile(): \"$source_\" does not exist"
    return 1
  fi

  case "$(cat $source_)" in *$to_test_*) return 0;; esac
  return 1
}

# same for strings
function stringInString
{
  local to_test_="$1"   # matching pattern
  local source_="$2"    # string to search in

  case "$source_" in *$to_test_*) return 0;; esac
  return 1
}

# get value for bootparam given as first param
function getBootParam
{
  local param_to_search_="$1"
  local result_=''

  stringInString " $param_to_search_=" "$CMD_LINE__" || return 1
  result_="${CMD_LINE__##*$param_to_search_=}"
  result_="${result_%%[   ]*}"
  echo "$result_"
  return 0
}

# Check boot commandline for specified option
function checkBootParam
{
  stringInString " $1" "$CMD_LINE__"
  return "$?"
}


# NETWORK  {{{

# validates an IP FIXME
function netValidIp
{
  local ip_="$1"    # ip addresse to validate
  local error_function_=${2:-"eprint"}    # function to call on error
  local message_="$3"    # user supplied error message
  
  local ret_=''

  echo "$ip_" | grep -E -q -e '[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}.[0-9]{1,3}' \
    &>/dev/null
  ret_=$?
  if [ $ret_ -ne 0 ]; then
    if [ -z "$message_" ]; then
      "$error_function_" "ip-addresse \"$ip_\" is NOT valied" $ret_
    else
      "$error_function_" "$message_" $ret_
    fi
    return 1
  fi

  dprint "ip-addresse \"$ip_\" is valied" $ret_
  return $ret_
}

function netGetIfaces
{
  local error_function_=${1:-"eprint"}    # function to call on error
  local message_="$2"    # user supplied error message
  local if_=''
  local ret_=''

  #ip a|grep 'inet ' |awk '$NF !~ /lo/{print $NF}'
  if_="`ip a|grep 'inet ' |awk '{print $NF}'`"
  ret_=$?
  if [ -z "$if_" ]; then
    if [ -z "$message_" ]; then
      "$error_function_" "no interfaces found" $ret_
    else
      "$error_function_" "$message_" $ret_
    fi
    return 1
  fi
  dprint "interfaces found" $ret_
  echo "$if_"
}

# FIXME
function netGetDefaultGateway
{
  local error_function_=${1:-"eprint"}    # function to call on error
  local message_="$2"    # user supplied error message
  
  local ip_=''
  local ret_=''
  
  setCLang
  ip_=`route -n | awk '/^0\.0\.0\.0/{print $2; exit}'`
  ret_=$?
  restoreLang
  if [ -z "$ip_" ]; then
    if [ -z "$message_" ]; then
      "$error_function_" "no default gateway found" $ret_
    else
      "$error_function_" "$message_" $ret_
    fi
    return 1
  fi
  dprint "default gateway is \"$ip_\"" $ret_
  echo "$ip_"
  return 0
}

# FIXME
function netGetNetmask
{
  local iface_="$1"
  local error_function_=${2:-"eprint"}    # function to call on error
  local message_="$3"    # user supplied error message
  
  local nm_=''
  local ret_=''
  
  setCLang
  nm_=`ifconfig "$iface_" | awk '/[Mm]ask/{FS="[:   ]*"; $0=$0; print $8; exit}'`
  ret_=$?
  restoreLang
  if [ -z "$nm_" ]; then
    if [ -z "$message_" ]; then
      "$error_function_" "could not find a netmask for \"$iface_\"" $ret_
    else 
      "$error_function_" "$message_" $ret_
    fi
    return 1
  fi
  dprint "netmask on \"$iface_\" is \"$nm_\"" $ret_
  echo "$nm_"
  return 0
}

# FIXME
function netGetIp
{
  local iface_="$1"
  local error_function_=${2:-"eprint"}    # function to call on error
  local message_="$3"    # user supplied error message

  local ip_=""
  local ret_=""

  setCLang
  #ip_=`ip addr list eth0 |mawk '/inet/{split($2,A,"/"); print A[1]}'`
  ip_=`ifconfig "$iface_" | awk '/[Ii]net [Aa]ddr/{FS="[:  ]*"; $0=$0; print $4; exit}'`
  ret_=$?
  restoreLang
  if [ -z "$ip_" ]; then
    if [ -z "$message_" ]; then
      "$error_function_" "no ip for \"$iface_\" found" $ret_
    else
      "$error_function_" "$message_" $ret_
    fi
    return 1
  fi
  dprint "addresse for \"$iface_\" is \"$ip_\"" $ret_
  echo "$ip_"
  return 0
} 

function netGetNameservers
{
  local error_function_=${1:-"eprint"}    # function to call on error
  local message_="$2"    # user supplied error message
  
  local file_="/etc/resolv.conf"
  local ns_=""

  if [ ! -e $file_ ]; then
    warn "file \"$file_\" does not exist, could not get nameservers"
    return 1
  fi
  
  setCLang
  ns_=`awk '/^nameserver/{printf "%s ",$2}' $file_ |xargs echo`
  restoreLang
  if [ -z "$ns_" ]; then
    if [ -z "$message_" ]; then
      "$error_function_" "no nameservers found" $ret_
    else
      "$error_function_" "$message_" $ret_
    fi
    return 1
  fi
  dprint "nameservers: \"$ns_\"" $ret_
  echo "$ns_"
  return 0
}

# }}}

# SERVICES {{{
function _touchService
{
  local action_="${1:-"start"}"
  local service_="$2"
  local error_function_=${3:-"eprint"}    # function to call on error
  local message_="$4"     # user supplied error message

  local i=""
  local known_action_='false'
  for i in "start" "stop" "restart" "reload" "force-reload"; do
    if [[ $i == $action_ ]]; then
      known_action_='true'
      break
    fi
  done
  $known_action_ || warn "_touchService(): unknown action \"$action_\""


  local service_path_=""
  service_path_="${INITD_DIR__}/$service_"
  if [ ! -e "$service_path_" ]; then
    warn "_touchService(): service does not exist: \"$service_\""
    return 1
  fi
  if [ ! -x "$service_path_" ]; then
    warn "_touchService(): service is not executable: \"$service_\""
  fi
  
  local ret_=""
  "$service_path_" "$action_"
  ret_=$?
  if [[ $ret_ != 0 ]]; then
    if [ -z "$message_" ]; then
      "$error_function_" "Problems ${action_}ing service \"$service_\"" $ret_
    else
      "$error_function_" "$message_" $ret_
    fi
    return 1
  fi
  dprint "_touchService(): successfully started service \"$service_\""
  return 0
}

function _createServiceFunctions
{
  for i in "start" "stop" "restart" "reload" "force-reload"; do
    eval "function ${i}Service { _touchService ${i} \"\$1\" \"\$2\" \"\$3\"; }"
  done
}
_createServiceFunctions
# }}}

# prints the next free /dev/loop* to stdout
function findNextFreeLoop
{
  local error_function_=${1:-"eprint"}    # function to call on error
  local message_="$2"    # user supplied error message

  local tmp_=''   # tmp
  local i=''      # counter
  local ret_=''   # saved return value
  
  for i in 'losetup' 'losetup.orig'; do
    tmp_=`$i -f 2>/dev/null`
    if [ $? -eq 0 ]; then
      echo $tmp_
      return 0
    fi
  done

  # we have to search
  dprint 'findNextFreeLoop(): losetup does not recognice option -f, searching next free loop device'
  for i in `seq 0 100`; do
    test -e /dev/loop$i || continue
    losetup /dev/loop$i &>/dev/null
    ret_=$?
    case "$ret_" in
      2) continue ;;  # losetup could not get status of loopdevice (EPERM)
      0) continue ;;  # device exist
      1) echo "/dev/loop$i"; return 0 ;;  # device does not exist and no error
      ?) continue ;;  # return value not available in 'man losetup'
    esac
  done

  # hmm... could not find a loopdevice
  if [ -z "$message_" ]; then
    $error_function_ "could not find a free loop device"
  else
    $error_function_ "$message_"
  fi
  return 1
}


# INIT {{{

function _initProgName
{
  local name_="$1"    # program name
  
  local tmp_name_=`basename "$name_"` || \
    logger -p user.alert -i "Init-initProgName: problems executing ( basename \"$name_\" ) ret($?)" >/dev/null
  
  secureInput "$tmp_name_"
}
PROG_NAME__=`_initProgName "$0"`


function _checkExecutables
{
  local tmp_=""
  for i in tr dirname basename id logger kill cat grep route awk ifconfig; do
    type -p $i &>/dev/null || tmp_="${tmp_}$i "
  done
  if [ -n "$tmp_" ]; then
    eprint "Init-checkExecutables: following executables not found or not executable:\n$tmp_"
    #syslog "Init-checkExecutables: following executables not found or not executable: $tmp_"
  fi
}
_checkExecutables


function _checkBootParam
{
  local path_="/proc/cmdline"
  if [ -e "$path_" ]; then
    CMD_LINE__=`execute "cat $path_" warnLog`
    return 0
  fi
  warnLog "$path_ does not exist, thus sh-lib may not work reliable!"
  return 1
}
_checkBootParam


function _setDebugLevel
{
  local debug_="${DEBUG:-0}"
  VERBOSE__="$debug_"
}
_setDebugLevel
# }}}

# END OF FILE
################################################################################
# vim:foldmethod=marker expandtab shiftwidth=2 tabstop=2