source: trunk/essentials/app-shells/bash/examples/functions/getoptx.bash@ 3951

#From: "Grigoriy Strokin" <[email protected]>
#Newsgroups: comp.unix.shell
#Subject: BASH: getopt function that parses long-named options
#Date: Mon, 22 Dec 1997 20:35:18 +0300

#Hi, I have written a BASH function named getoptex, that is like bash builtin
#"getopts", but does parse long-named options and optional arguments. It only
#uses builtin bash commands, so it is very fast.  In order to use it in your
#bash scripts, include a command ". getopt.sh" (<dot> getopt.sh) to the file
#containing your script, and that will define functions getopt, getoptex, and
#optlistex (the file getopt.sh with its detailed description is listed
#below).

#*** file getopt.sh ***

#! /bin/bash
#
# getopt.sh:
# functions like getopts but do long-named options parsing
# and support optional arguments
#
# Version 1.0 1997 by Grigoriy Strokin ([email protected]), Public Domain
# Date created:  December 21, 1997
# Date modified: December 21, 1997
#
# IMPORTANT FEATURES
#
# 1) Parses both short and long-named options
# 2) Supports optional arguments
# 3) Only uses bash builtins, thus no calls to external
#    utilities such as expr or sed is done. Therefore,
#    parsing speed is high enough
#
#
# DESCRIPTION
#
# FUNCTION getopt
# Usage: getopt OPTLIST {"$@"|ALTERNATIVE_PARAMETERS}
#
# like getopts, but parse options with both required and optional arguments,
# Options with optional arguments must have "." instead of ":" after them.
# Furthemore, a variable name to place option name cannot be specified
# and is always placed in OPTOPT variable
#
# This function is provided for compatibility with getopts()
# OPTLIST style, and it actually calls getoptex (see bellow)
#
# NOTE that a list of parameters is required and must be either "$@",
# if processing command line arguments, or some alternative parameters.
#
# FUNCTION getoptex
# Usage: getoptex OPTION_LIST {"$@"|ALTERNATIVE_PARAMETERS}
#
# like getopts, but parse long-named options.
#
# Both getopt and getoptex return 0 if an option has been parsed,
# and 1 if all options are already parsed or an error occured
#
# Both getopt and getoptex set or test the following variables:
#
# OPTERR -- tested for whether error messages must be given for invalid
options
#
# OPTOPT -- set to the name of an option parsed,
#           or to "?" if no more options or error
# OPTARG -- set to the option argument, if any;
#           unset if ther is no argument;
#           on error, set to the erroneous option name
#
# OPTIND -- Initialized to 1.
#           Then set to the number of the next parameter to be parsed
#           when getopt or getoptex will be called next time.
#           When all options are parsed, contains a number of
#           the first non-option argument.
#
#
# OPTOFS -- If a parameter number $OPTIND containg an option parsed
#           does not contain any more options, OPTOFS is unset;
#           otherwise, OPTOFS is set to such a number of "?" signs
#           which is equal to the number of options parsed
#
#           You might not set variables OPTIND and OPTOFS yourself
#           unless you want to parse a list of parameters more than once.
#           Otherwise, you whould unset OPTIND (or set it to 1)
#           and unset OPTOFS each time you want to parse a new parameters
list
#
# Option list format is DIFFERENT from one for getopts or getopt.
getopts-style
# option list can be converted to getoptex-style using a function optlistex
# (see bellow)
#
# DESCRIPTION of option list used with getoptex:
# Option names are separated by whitespace. Options consiting of
# more than one character are treated as long-named (--option)
#
# Special characters can appear at the and of option names specifying
# whether an argument is required (default is ";"):
# ";" (default) -- no argument
# ":" -- required argument
# "," -- optional argument
#
# For example, an option list "a b c help version f: file: separator."
# defines the following options:
#    -a, -b, -c, --help, --version -- no argument
#    -f, --file -- argument required
#    --separator -- optional argument
#
# FUNCTION optlistex
# Usage new_style_optlist=`optlistex OLD_STYLE_OPTLIST`
#
# Converts getopts-style option list in a format suitable for use with getoptex
# Namely, it inserts spaces after each option name.
#
#
# HOW TO USE
#
# In order o use in your bash scripts the functions described,
# include a command ". getopt.sh" to the file containing the script,
# which will define functions getopt, getoptex, and optlistex
#
# EXAMPLES
#
# See files 'getopt1' and 'getopt2' that contain sample scripts that use
# getopt and getoptex functions respectively
#
#
# Please send your comments to [email protected]

function getoptex()
{
  let $# || return 1
  local optlist="${1#;}"
  let OPTIND || OPTIND=1
  [ $OPTIND -lt $# ] || return 1