#From: "Grigoriy Strokin" #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" ( 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 (grg@philol.msu.ru), 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 grg@philol.msu.ru function getoptex() { let $# || return 1 local optlist="${1#;}" let OPTIND || OPTIND=1 [ $OPTIND -lt $# ] || return 1 shift $OPTIND if [ "$1" != "-" ] && [ "$1" != "${1#-}" ] then OPTIND=$[OPTIND+1]; if [ "$1" != "--" ] then local o o="-${1#-$OPTOFS}" for opt in ${optlist#;} do OPTOPT="${opt%[;.:]}" unset OPTARG local opttype="${opt##*[^;:.]}" [ -z "$opttype" ] && opttype=";" if [ ${#OPTOPT} -gt 1 ] then # long-named option case $o in "--$OPTOPT") if [ "$opttype" != ":" ]; then return 0; fi OPTARG="$2" if [ -z "$OPTARG" ]; then # error: must have an agrument let OPTERR && echo "$0: error: $OPTOPT must have an argument" >&2 OPTARG="$OPTOPT"; OPTOPT="?" return 1; fi OPTIND=$[OPTIND+1] # skip option's argument return 0 ;; "--$OPTOPT="*) if [ "$opttype" = ";" ]; then # error: must not have arguments let OPTERR && echo "$0: error: $OPTOPT must not have arguments" >&2 OPTARG="$OPTOPT" OPTOPT="?" return 1 fi OPTARG=${o#"--$OPTOPT="} return 0 ;; esac else # short-named option case "$o" in "-$OPTOPT") unset OPTOFS [ "$opttype" != ":" ] && return 0 OPTARG="$2" if [ -z "$OPTARG" ] then echo "$0: error: -$OPTOPT must have an argument" >&2 OPTARG="$OPTOPT" OPTOPT="?" return 1 fi OPTIND=$[OPTIND+1] # skip option's argument return 0 ;; "-$OPTOPT"*) if [ $opttype = ";" ] then # an option with no argument is in a chain of options OPTOFS="$OPTOFS?" # move to the next option in the chain OPTIND=$[OPTIND-1] # the chain still has other options return 0 else unset OPTOFS OPTARG="${o#-$OPTOPT}" return 0 fi ;; esac fi done echo "$0: error: invalid option: $o" fi; fi OPTOPT="?" unset OPTARG return 1 } function optlistex { local l="$1" local m # mask local r # to store result while [ ${#m} -lt $[${#l}-1] ]; do m="$m?"; done # create a "???..." mask while [ -n "$l" ] do r="${r:+"$r "}${l%$m}" # append the first character of $l to $r l="${l#?}" # cut the first charecter from $l m="${m#?}" # cut one "?" sign from m if [ -n "${l%%[^:.;]*}" ] then # a special character (";", ".", or ":") was found r="$r${l%$m}" # append it to $r l="${l#?}" # cut the special character from l m="${m#?}" # cut one more "?" sign fi done echo $r } function getopt() { local optlist=`optlistex "$1"` shift getoptex "$optlist" "$@" return $? } #************************************** # cut here #************************************** #*** (end of getopt.sh) *** #*** file getopt1 *** #! /bin/bash # getopt1: # Sample script using the function getopt # # Type something like "getopt1 -ab -d 10 -e20 text1 text2" # on the command line to see how it works # # See getopt.sh for more information #. getopt.sh #echo Using getopt to parse arguments: #while getopt "abcd:e." "$@" #do # echo "Option ${OPTARG:+has an arg }" #done #shift $[OPTIND-1] #for arg in "$@" #do # echo "Non option argument " #done # #************************************** # cut here #************************************** #*** (end of getopt1) *** # # #*** file getopt2 *** # #! /bin/bash # getopt2: # Sample script using the function getoptex # # Type something like "getopt2 -ab -d 10 -e20 --opt1 --opt4=100 text1 text2" # to see how it works # # See getopt.sh for more information . getopt.sh #echo Using getoptex to parse arguments: #while getoptex "a; b; c; d: e. opt1 opt2 opt3 opt4: opt5." "$@" #do # echo "Option ${OPTARG:+has an arg }" #done #shift $[OPTIND-1] #for arg in "$@" #do # echo "Non option argument " #done # #************************************** # cut here #************************************** #*** (end of getopt2) ***
