Merge branch 'parse-opts'

1 files changed, 141 insertions, 0 deletions

diff --git a/scripts/library/parseopts.sh b/scripts/library/parseopts.sh
new file mode 100644
index 00000000..11589ce3
--- /dev/null
+++ b/scripts/library/parseopts.sh
@@ -0,0 +1,141 @@
+# getopt-like parser
+parseopts() {
+	local opt= optarg= i= shortopts=$1
+	local -a longopts=() unused_argv=()
+
+	shift
+	while [[ $1 && $1 != '--' ]]; do
+		longopts+=("$1")
+		shift
+	done
+	shift
+
+	longoptmatch() {
+		local o longmatch=()
+		for o in "${longopts[@]}"; do
+			if [[ ${o%:} = "$1" ]]; then
+				longmatch=("$o")
+				break
+			fi
+			[[ ${o%:} = "$1"* ]] && longmatch+=("$o")
+		done
+
+		case ${#longmatch[*]} in
+			1)
+				# success, override with opt and return arg req (0 == none, 1 == required)
+				opt=${longmatch%:}
+				if [[ $longmatch = *: ]]; then
+					return 1
+				else
+					return 0
+				fi ;;
+			0)
+				# fail, no match found
+				return 255 ;;
+			*)
+				# fail, ambiguous match
+				printf "@SCRIPTNAME@: $(gettext "option '%s' is ambiguous; possibilities:")" "--$1"
+				printf " '%s'" "${longmatch[@]%:}"
+				printf '\n'
+				return 254 ;;
+		esac >&2
+	}
+
+	while (( $# )); do
+		case $1 in
+			--) # explicit end of options
+				shift
+				break
+				;;
+			-[!-]*) # short option
+				for (( i = 1; i < ${#1}; i++ )); do
+					opt=${1:i:1}
+
+					# option doesn't exist
+					if [[ $shortopts != *$opt* ]]; then
+						printf "@SCRIPTNAME@: $(gettext "invalid option") -- '%s'\n" "$opt" >&2
+						OPTRET=(--)
+						return 1
+					fi
+
+					OPTRET+=("-$opt")
+					# option requires optarg
+					if [[ $shortopts = *$opt:* ]]; then
+						# if we're not at the end of the option chunk, the rest is the optarg
+						if (( i < ${#1} - 1 )); then
+							OPTRET+=("${1:i+1}")
+							break
+						# if we're at the end, grab the the next positional, if it exists
+						elif (( i == ${#1} - 1 )) && [[ $2 ]]; then
+							OPTRET+=("$2")
+							shift
+							break
+						# parse failure
+						else
+							printf "@SCRIPTNAME@: $(gettext "option requires an argument") -- '%s'\n" "$opt" >&2
+							OPTRET=(--)
+							return 1
+						fi
+					fi
+				done
+				;;
+			--?*=*|--?*) # long option
+				IFS='=' read -r opt optarg <<< "${1#--}"
+				longoptmatch "$opt"
+				case $? in
+					0)
+						# parse failure
+						if [[ $optarg ]]; then
+							printf "@SCRIPTNAME@: $(gettext "option '%s' does not allow an argument")\n" "--$opt" >&2
+							OPTRET=(--)
+							return 1
+						# --longopt
+						else
+							OPTRET+=("--$opt")
+							shift
+							continue 2
+						fi
+						;;
+					1)
+						# --longopt=optarg
+						if [[ $optarg ]]; then
+							OPTRET+=("--$opt" "$optarg")
+							shift
+						# --longopt optarg
+						elif [[ $2 ]]; then
+							OPTRET+=("--$opt" "$2" )
+							shift 2
+						# parse failure
+						else
+							printf "@SCRIPTNAME@: $(gettext "option '%s' requires an argument")\n" "--$opt" >&2
+							OPTRET=(--)
+							return 1
+						fi
+						continue 2
+						;;
+					254)
+						# ambiguous option -- error was reported for us by longoptmatch()
+						OPTRET=(--)
+						return 1
+						;;
+					255)
+						# parse failure
+						printf "@SCRIPTNAME@: $(gettext "invalid option") '--%s'\n" "$opt" >&2
+						OPTRET=(--)
+						return 1
+						;;
+				esac
+				;;
+			*) # non-option arg encountered, add it as a parameter
+				unused_argv+=("$1")
+				;;
+		esac
+		shift
+	done
+
+	# add end-of-opt terminator and any leftover positional parameters
+	OPTRET+=('--' "${unused_argv[@]}" "$@")
+	unset longoptmatch
+
+	return 0
+}