X-Git-Url: http://git.tuebingen.mpg.de/?p=gsu.git;a=blobdiff_plain;f=subcommand;h=1b204e0dc3abe0f31ab8de41b6f148acfb6ec0cf;hp=bab8ded4ea1d9f0b99562eca7dc8d257244062a0;hb=refs%2Fheads%2Fpu;hpb=8d89aa241a5199b0a25edcf0e56da08c64aa4014

diff --git a/subcommand b/subcommand
index bab8ded..d37481c 100644
--- a/subcommand
+++ b/subcommand
@@ -1,15 +1,16 @@
 #!/bin/bash
-# (C) 2006-2011 Andre Noll
+# Copyright (C) 2006 Andre Noll
+# Licensed under the LGPL, version 3. See COPYING and COPYING.LESSER.
 
 if [[ "$(type -t _gsu_setup)" != "function" ]]; then
 	gsu_dir=${gsu_dir:-${BASH_SOURCE[0]%/*}}
-	. $gsu_dir/common || exit 1
+	. "$gsu_dir/common" || exit 1
 	_gsu_setup
 fi
 
 _gsu_usage()
 {
-	gsu_short_msg "# Usage: $_gsu_self command [options]"
+	gsu_short_msg "# Usage: $gsu_name command [options]"
 }
 
 # Return an extended regular expression to match against $0.
@@ -24,7 +25,7 @@ _gsu_usage()
 # exactly one parenthesized subexpression for matching the command name.
 _gsu_get_command_regex()
 {
-	local cmd="${1:-[-a-zA-Z_0-9]+}"
+	local cmd="${1:-[-a-zA-Z_0-9]{1,\}}"
 	result="^com_($cmd)\(\)"
 }
 
@@ -45,30 +46,155 @@ _gsu_available_commands()
 
 			# otherwise delete it
 			d
-		' $0
+		' "$0"
 	} | sort | tr '\n' ' ')"
 }
 
-_gsu_print_available_commands()
-{(
-	local i count=0
-	gsu_short_msg "Available commands:"
-	for i in $gsu_cmds; do
-		printf "$i"
-		count=$(($count + 1))
-		if test $(($count % 4)) -eq 0; then
-			echo
+# Check number of arguments.
+#
+# Usage: gsu_check_arg_count <num_given> <num1> [<num2>]
+#
+# Check that <num_given> is between <num1> and <num2> inclusively.
+# If only <num1> ist given, num2 is assumed to be infinity.
+#
+# Examples:
+# 	0 0 no argument allowed
+# 	1 1 exactly one argument required
+# 	0 2 at most two arguments admissible
+# 	2   at least two arguments required
+gsu_check_arg_count()
+{
+	ret=-$E_GSU_BAD_ARG_COUNT
+	if (($# == 2)); then # only num1 is given
+		result="at least $2 args required, $1 given"
+		(($1 < $2)) && return
+		ret=$GSU_SUCCESS
+		return
+	fi
+	# num1 and num2 given
+	result="need at least $2 args, $1 given"
+	(($1 < $2)) && return
+	result="need at most $3 args, $1 given"
+	(($1 > $3)) && return
+	ret=$GSU_SUCCESS
+}
+
+# Wrapper for the bash getopts builtin.
+#
+# Aborts on programming errors such as missing or invalid option string.  On
+# success $result contains shell code that can be eval'ed. For each defined
+# option x, the local variable o_x will be created when calling eval "$result".
+# o_x contains true/false for options without argument and either the empty
+# string or the given argument for options that take an argument.
+#
+# Example:
+# 	gsu_getopts abc:x:y
+# 	eval "$result"
+# 	(($ret < 0)) && return
+#
+# 	[[ "$o_a" = 'true' ]] && echo 'The -a flag was given'
+# 	[[ -n "$o_c" ]] && echo "The -c option was given with arg $o_c"
+gsu_getopts()
+{
+	local -i i
+	local c c1 c2 tab='	' cr='
+'
+
+	gsu_check_arg_count $# 1 1
+	if ((ret < 0)); then
+		gsu_err_msg
+		exit 1
+	fi
+
+	ret=-$E_GSU_GETOPTS
+	result="invalid optstring $1"
+	if [[ -z "$1" ]] || grep -q '::' <<< "$1" ; then
+		gsu_err_msg
+		exit 1
+	fi
+
+	for ((i=0; i < ${#1}; i++)); do
+		c=${1:$i:1}
+		case "$c" in
+		[a-zA-Z:]);;
+		*)
+			ret=-$E_GSU_GETOPTS
+			result="invalid character $c in optstring"
+			gsu_err_msg
+			exit 1
+		esac
+	done
+	result="local _gsu_getopts_opt"
+	for ((i=0; i < ${#1}; i++)); do
+		c1=${1:$i:1}
+		c2=${1:$((i + 1)):1}
+		result+=" o_$c1="
+		if [[ "$c2" = ":" ]]; then
+			let i++
 		else
-			printf "\t"
-			if test ${#i} -lt 8; then
-				printf "\t"
-			fi
+			result+="false"
 		fi
 	done
-	echo
-) 2>&1
+	result+="
+	OPTIND=1
+	while getopts $1 _gsu_getopts_opt \"\$@\"; do
+		case \"\$_gsu_getopts_opt\" in
+"
+	for ((i=0; i < ${#1}; i++)); do
+		c1=${1:$i:1}
+		c2=${1:$((i + 1)):1}
+		result+="$tab$tab$c1) o_$c1="
+		if [[ "$c2" = ":" ]]; then
+			result+="\"\$OPTARG\""
+			let i++
+		else
+			result+="true"
+		fi
+		result+=";;$cr"
+	done
+	result+="
+		*)
+			ret=-\$E_GSU_GETOPTS
+			result=\"invalid option given\"
+			return
+			;;
+		esac
+	done
+	shift \$((\$OPTIND - 1))
+"
+	ret=$GSU_SUCCESS
+}
+
+_gsu_print_available_commands()
+{
+	local cmd cmds
+	local -i maxlen=0 cols width=80 count=0
+
+	result=$(stty size 2>/dev/null)
+	if (($? == 0)); then
+		gsu_is_a_number "${result#* }"
+		((ret >= 0)) && ((result > 0)) && width=$result
+	fi
+	_gsu_available_commands
+	cmds=$result
+	for cmd in $cmds; do
+		((${#cmd} > maxlen)) && maxlen=${#cmd}
+	done
+	let maxlen++
+	((width < maxlen)) && cols=1 || cols=$((width / maxlen))
+	printf 'Available commands:'
+	for cmd in $cmds; do
+		((count % cols == 0)) && printf '\n'
+		printf '%-*s' $maxlen $cmd
+		let ++count
+	done
+	printf '\n'
 }
 
+# Print all options of the given optstring to stdout if the word in the current
+# command line begins with a hyphen character.
+#
+# Returns 0 if the current word does not start with a hyphen, one otherwise.
 gsu_complete_options()
 {
 	local opts="$1" cword="$2" cur opt
@@ -80,42 +206,46 @@ gsu_complete_options()
 	ret=0
 	[[ ! "$cur" == -* ]] && return
 
-	ret=0
 	for ((i=0; i < ${#opts}; i++)); do
 		opt="${opts:$i:1}"
 		[[ "$opt" == ":" ]] && continue
 		printf "%s" "-$opt "
-		let ret++
 	done
+	ret=1
 }
 
-export gsu_prefs_txt="
+declare -A _gsu_help_text=() # indexed by autocmd
+com_prefs_options='e'
+
+_gsu_help_text['prefs']='
 Print the current preferences.
 
 Usage: prefs [-e]
 
-If -e is given, the config file is opened with the default editor.  Without
-options, the command prints out a list of all cmt config variables, together
-with their current value and the default value."
-_com_prefs()
+If -e is given, the config file is opened with the default editor.
+Without options, the command prints out a list of all config variables,
+together with their current value and the default value.
+'
+
+com_prefs()
 {
 	local i conf="${gsu_config_file:=${HOME:-}/.$gsu_name.rc}"
 
-	gsu_getopts "e"
+	gsu_getopts "$com_prefs_options"
 	eval "$result"
-	(($ret < 0)) && return
+	((ret < 0)) && return
 	gsu_check_arg_count $# 0 0
-	(($ret < 0)) && return
+	((ret < 0)) && return
 
 	if [[ "$o_e" == "true" ]]; then
 		ret=-$E_GSU_MKDIR
 		result="${conf%/*}"
 		mkdir -p "$result"
-		[[ $? -ne 0 ]] && return
+		(($? != 0)) && return
 		ret=-$E_GSU_EDITOR
 		result="${EDITOR:-vi}"
-		"$result" "$conf"
-		[[ $? -ne 0 ]] && return
+		"$result" $conf
+		(($? != 0)) && return
 		ret=$GSU_SUCCESS
 		return
 	fi
@@ -133,43 +263,334 @@ _com_prefs()
 			printf "# optional"
 			;;
 		esac
-		printf " $option_type: $description"
+		printf " %s: %s" "$option_type" "$description"
 		if [[ "$required" != "yes" && "$required" != "true" ]]; then
-			printf " [$default_value]"
+			printf " [%s]" "$default_value"
 		fi
 		echo
 		[[ -n "$help_text" ]] && sed -e '/^[	]*$/d; s/^[ 	]*/#	/g' <<< "$help_text"
-		printf "$name=$val"
+		printf "%s=%s" "$name" "$val"
 		[[ "$val" == "$default_value" ]] && printf " # default"
 		echo
 	done
 }
 
+_gsu_isatty()
+{(
+	exec 3<&1
+	stty 0<&3 &> /dev/null
+)}
+
 complete_prefs()
 {
-	gsu_complete_options "e" "$@"
+	gsu_complete_options "$com_prefs_options" "$@"
+}
+
+_gsu_man_options='m:b:'
+
+complete_man()
+{
+	gsu_complete_options "$_gsu_man_options" "$@"
+	((ret > 0)) && return
+	gsu_cword_is_option_parameter "$_gsu_man_options" "$@"
+	[[ "$result" == 'm' ]] && printf 'roff\ntext\nhtml\n'
 }
 
-export gsu_man_txt="
+_gsu_help_text['man']='
 Print the manual.
 
-Usage: man"
+Usage: man [-m <mode>] [-b <browser>]
+
+-m: Set output format (text, roff or html). Default: roff.
+-b: Use the specified browser. Implies html mode.
+
+If stdout is not associated with a terminal device, the command
+dumps the man page to stdout and exits.
+
+Otherwise, it tries to display the manual page as follows. In text
+mode, plain text is piped to $PAGER. In roff mode, the roff output
+is filtered through nroff, then piped to $PAGER. For both formats,
+if $PAGER is unset, less(1) is assumed.
+
+In html mode, html output is written to a temporary file, and this
+file is displayed as a page in the web browser. If -b is not given,
+the command stored in the $BROWSER environment variable is executed
+with the path to the temporary file as an argument. If $BROWSER is
+unset, elinks(1) is assumed.
+'
+
+_gsu_read_line()
+{
+	local -n p="$1"
+	local l OIFS="$IFS"
+
+	IFS=
+	read -r l || return
+	IFS="$OIFS"
+	p="$l"
+}
+
+_gsu_change_roffify_state()
+{
+	local -n statep="$1"
+	local new_state="$2"
+	local old_state="$statep"
+
+	[[ "$old_state" == "$new_state" ]] && return 0
+
+	case "$old_state" in
+	text);;
+	example) printf '.EE\n';;
+	enum) printf '.RE\n';;
+	esac
+	case "$new_state" in
+	text);;
+	example) printf '.EX\n';;
+	enum) printf '.RS 2\n';;
+	esac
+
+	statep="$new_state"
+	return 1
+}
+
+_gsu_print_protected_roff_line()
+{
+	local line="$1"
+	local -i n=0
+
+	while [[ "${line:$n:1}" == ' ' ]]; do
+		let n++
+	done
+	line="${line:$n}"
+	printf '\\&%s\n' "${line//\\/\\\\}"
+}
+
+_gsu_roffify_maindoc()
+{
+	local state='text' TAB='	'
+	local line next_line
+	local -i n
+
+	_gsu_read_line 'line' || return
+	while _gsu_read_line next_line; do
+		if [[ "$next_line" =~ ^(----|====|~~~~) ]]; then # heading
+			printf '.SS %s\n' "$line"
+			_gsu_read_line line || return
+			_gsu_change_roffify_state 'state' 'text'
+			continue
+		fi
+		if [[ "${line:0:1}" == "$TAB" ]]; then # example
+			_gsu_change_roffify_state 'state' 'example'
+			_gsu_print_protected_roff_line "$line"
+			line="$next_line"
+			continue
+		fi
+		n=0
+		while [[ "${line:$n:1}" == ' ' ]]; do
+			let n++
+		done
+		line=${line:$n};
+		if [[ "${line:0:1}" == '*' ]]; then # enum
+			line=${line#\*}
+			_gsu_change_roffify_state 'state' 'enum'
+			printf '\n\(bu %s\n' "$line"
+			line="$next_line"
+			continue
+		fi
+		if [[ "$line" =~ ^$ ]]; then # new paragraph
+			_gsu_change_roffify_state 'state' 'text'
+			printf '.PP\n'
+		else
+			_gsu_print_protected_roff_line "$line"
+		fi
+		line="$next_line"
+	done
+	_gsu_print_protected_roff_line "$line"
+}
+
+_gsu_extract_maindoc()
+{
+	sed -e '1,/^#\{70,\}/d' -e '/^#\{70,\}/,$d' -e 's/^# *//' -e 's/^#//g' "$0"
+}
+
+_gsu_roffify_cmds()
+{
+	local line cmd= desc= state='text' TAB='	'
+
+	while _gsu_read_line line; do
+		if [[ "${line:0:1}" != '#' ]]; then # com_foo()
+			line="${line#com_}"
+			cmd="${line%()}"
+			continue
+		fi
+		line="${line####}"
+		if [[ "$line" =~ ^[[:space:]]*$ ]]; then
+			printf '.PP\n'
+			_gsu_change_roffify_state 'state' 'text'
+			continue
+		fi
+		if [[ -n "$cmd" ]]; then # desc or usage
+			if [[ -z "$desc" ]]; then # desc
+				desc="$line"
+				continue
+			fi
+			# usage
+			_gsu_change_roffify_state 'state' 'text'
+			printf '\n.SS %s \\- %s\n' "$cmd" "$desc"
+			printf '\n.I %s\n'  "$line"
+			cmd=
+			desc=
+			continue
+		fi
+		line="${line# }"
+		if [[ "${line:0:1}" == "$TAB" ]]; then
+			_gsu_change_roffify_state 'state' 'example'
+			_gsu_print_protected_roff_line "$line"
+			continue
+		fi
+		if [[ "$line" == -*:* ]]; then
+			_gsu_change_roffify_state 'state' 'enum'
+			printf '.PP\n.B %s:\n' "${line%%:*}"
+			_gsu_print_protected_roff_line "${line#*:}"
+			continue
+		fi
+		_gsu_print_protected_roff_line "$line"
+	done
+}
+
+_gsu_roffify_autocmds()
+{
+	local cmd help_txt
+
+	for cmd in "${!_gsu_help_text[@]}"; do
+		help_txt="${_gsu_help_text["$cmd"]}"
+		{
+			printf 'com_%s()\n' "$cmd"
+			sed -e 's/^/## /g' <<< "$help_txt"
+		} | _gsu_roffify_cmds
+	done
+}
+
+_gsu_roff_man()
+{
+	local name="$1" sect_num="$2" month_year="$3" pkg="$4" sect_name="$5"
+	local purpose="$6"
+	local ere
+
+	cat << EOF
+.TH "${name^^}" "$sect_num" "$month_year" "$pkg" "$sect_name"
+.SH NAME
+$name \- $purpose
+.SH SYNOPSIS
+.B $name
+\fI\,<subcommand>\/\fR [\fI\,<options>\/\fR] [\fI\,<arguments>\/\fR]
+.SH DESCRIPTION
+EOF
+	_gsu_extract_maindoc | _gsu_roffify_maindoc
+
+	printf '\n.SH "GENERIC SUBCOMMANDS"\n'
+	printf 'The following commands are automatically created by gsu\n'
+	_gsu_roffify_autocmds
+
+	printf '\n.SH "LIST OF SUBCOMMANDS"\n'
+	printf 'Each command has its own set of options as described below.\n'
+
+	_gsu_get_command_regex
+	ere="$result"
+	# only consider lines in the comment of the function
+	sed -nEe '/'"$ere"'/,/^[^#]/p' "$0" | _gsu_roffify_cmds
+}
+
+_gsu_file_mtime()
+{
+	local file="$1"
+	result="$(find "$file" -printf '%TB %TY' 2>/dev/null)" # GNU
+	(($? == 0)) && [[ -n "$result" ]] && return
+	result="$(stat -f %Sm -t '%B %Y' "$file" 2>/dev/null)" # BSD
+	(($? == 0)) && [[ -n "$result" ]] && return
+	result="$(date '+%B %Y' 2>/dev/null)" # POSIX
+	(($? == 0)) && [[ -n "$result" ]] && return
+	result='[unknown date]'
+}
 
-_com_man()
+com_man()
 {
 	local equal_signs="=================================================="
 	local minus_signs="--------------------------------------------------"
-        local com num
+	local filter='cat' pager='cat' browser=${BROWSER:-elinks} tmpfile=
+	local com num isatty pipeline
 
-	echo "$_gsu_self (_${gsu_banner_txt}_) manual"
-	echo "${equal_signs:0:${#_gsu_self} + ${#gsu_banner_txt} + 16}"
-	echo
+	gsu_getopts "$_gsu_man_options"
+	eval "$result"
+	((ret < 0)) && return
+	if [[ -n "$o_b" ]]; then
+		o_m='html'
+		browser="$o_b"
+	elif [[ -z "$o_m" ]]; then
+		o_m='roff'
+	fi
 
-        sed -e '1,/^#\{70,\}/d' -e '/^#\{70,\}/,$d' $0 -e 's/^# *//'
+	_gsu_isatty && isatty='true' || isatty='false'
+	if [[ "$o_m" == 'roff' ]]; then
+		if [[ "$isatty" == 'true' ]]; then
+			filter='nroff -Tutf8 -mandoc'
+			pager="${PAGER:-less}"
+		fi
+	elif [[ "$o_m" == 'text' ]]; then
+		if [[ "$isatty" == 'true' ]]; then
+			pager="${PAGER:-less}"
+		fi
+	elif [[ "$o_m" == 'html' ]]; then
+		filter='groff -T html -m man'
+		if [[ "$isatty" == 'true' ]]; then
+			gsu_make_tempfile "gsu_html_man.XXXXXX.html"
+			((ret < 0)) && return || tmpfile="$result"
+			trap "rm -f $tmpfile" RETURN EXIT
+		fi
+	fi
+	[[ "$pager" == 'less' ]] && export LESS=${LESS-RI}
+	case "$o_m" in
+	roff|html)
+		_gsu_file_mtime	"$0"
+		_gsu_roff_man "$gsu_name" '1' "$result" \
+			"${gsu_package-${gsu_name^^}(1)}" \
+			"User Commands" "${gsu_banner_txt}" \
+		| $filter | {
+			if [[ -n "$tmpfile" ]]; then
+				cat > "$tmpfile"
+			else
+				$pager
+			fi
+		}
+		if (($? != 0)); then
+			ret=-$E_GSU_XCMD
+			result="filter: $filter"
+			return
+		fi
+		if [[ -n "$tmpfile" ]]; then
+			ret=-$E_GSU_XCMD
+			result="$browser"
+			"$browser" "$tmpfile" || return
+		fi
+		ret=$GSU_SUCCESS
+		return
+		;;
+	text) ;;
+	"") ;;
+	*)
+		ret=-$E_GSU_INVAL
+		result="$o_m"
+		return
+	esac
+	{
+	echo "$gsu_name (_${gsu_banner_txt}_) manual"
+	echo "${equal_signs:0:${#gsu_name} + ${#gsu_banner_txt} + 16}"
+	echo
+	_gsu_extract_maindoc
 	echo "----"
-        echo
-	echo "$_gsu_self usage"
-	echo "${minus_signs:0:${#_gsu_self} + 6}"
+	echo
+	echo "$gsu_name usage"
+	echo "${minus_signs:0:${#gsu_name} + 6}"
 	printf "\t"
 	_gsu_usage 2>&1
 	echo "Each command has its own set of options as described below."
@@ -179,34 +600,31 @@ _com_man()
 	echo "Available commands:"
 
 	_gsu_available_commands
-        for com in $result; do
+	for com in $result; do
 		num=${#com}
-		if test $num -lt 4; then
-			num=4
-		fi
-                echo "${minus_signs:0:$num}"
-                echo "$com"
-                echo "${minus_signs:0:$num}"
-                $0 help $com
+		((num < 4)) && num=4
+		echo "${minus_signs:0:$num}"
+		echo "$com"
+		echo "${minus_signs:0:$num}"
+		"$0" help "$com"
 		echo
-        done
-        ret=$GSU_SUCCESS
-}
-
-_gsu_banner_msg()
-{
-	gsu_short_msg "### $_gsu_self -- ###"
+	done
+	} | $pager
+	ret=$GSU_SUCCESS
 }
 
-export gsu_help_txt="
+_gsu_help_text['help']='
 Print online help.
 
-Usage: help [command]
+Usage: help [-a] [command]
 
 Without arguments, print the list of available commands. Otherwise,
-print the help text for the given command."
+print the help text for the given command.
+
+-a: Also show the help of automatic commands. Ignored if a command
+is given.'
 
-export gsu_complete_txt="
+_gsu_help_text['complete']='
 Command line completion.
 
 Usage: complete [<cword> <word>...]
@@ -218,24 +636,34 @@ completion.
 If at least one argument is given, all possible completions are
 written to stdout. This can be used from the completion function of
 the subcommand.
-"
+'
 
-_com_help()
+com_help_options='a'
+com_help()
 {
-	local a b ere tab='	'
+	local ere tab='	' txt
+
+	gsu_getopts "$com_help_options"
+	eval "$result"
+	((ret < 0)) && return
 
 	_gsu_get_command_regex
 	ere="$result"
 
 	if (($# == 0)); then
-		_gsu_banner_msg 2>&1
+		gsu_short_msg "### $gsu_name -- $gsu_banner_txt ###"
 		_gsu_usage 2>&1
 		{
-			printf "com_help()\n$gsu_help_txt" | head -n 4; echo "--"
-			printf "com_man()\n$gsu_man_txt" | head -n 4; echo "--"
-			printf "com_prefs()\n$gsu_prefs_txt" | head -n 4; echo "--"
-			printf "com_complete()\n$gsu_complete_txt" | head -n 4; echo "--"
-			grep -EA 2 "$ere" $0
+			if [[ "$o_a" == 'true' ]]; then
+				_gsu_mfcb() { printf '%s\n' "$2"; }
+				for cmd in "${!_gsu_help_text[@]}"; do
+					printf "com_%s()" "$cmd"
+					txt="${_gsu_help_text["$cmd"]}"
+					mapfile -n 3 -c 1 -C _gsu_mfcb <<< "$txt"
+				printf -- '--\n'
+				done
+			fi
+			grep -EA 2 "$ere" "$0"
 		} | grep -v -- '--' \
 			| sed -En "/$ere/"'!d
 				# remove everything but the command name
@@ -256,36 +684,36 @@ _com_help()
 				y/\n/'"$tab"'/
 
 				# and print the sucker
-				p'
-		echo
-		echo "# Try $_gsu_self help <command> for info on <command>."
-		ret=$GSU_SUCCESS
-		return
-	fi
-	if test "$1" = "help"; then
-		echo "$gsu_help_txt"
-		ret=$GSU_SUCCESS
-		return
-	fi
-	if test "$1" = "man"; then
-		echo "$gsu_man_txt"
-		ret=$GSU_SUCCESS
-		return
-	fi
-	if test "$1" = "prefs"; then
-		echo "$gsu_prefs_txt"
+				p
+			' | {
+				local -a cmds=() descs=()
+				local -i i maxlen=1
+				local cmd desc
+				while read cmd desc; do
+					((maxlen < ${#cmd})) && maxlen=${#cmd}
+					cmds[${#cmds[@]}]=$cmd
+					descs[${#descs[@]}]=$desc
+				done
+				for ((i = 0; i < ${#cmds[@]}; i++)); do
+					printf '%-*s %s\n' $maxlen ${cmds[$i]} \
+						"${descs[$i]}"
+				done
+			}
+		printf "\n# Try %s help <command> for info on <command>, or %s help -a to see\n" \
+			"$gsu_name" "$gsu_name"
+		printf '# also the subcommands which are automatically generated by gsu.\n'
 		ret=$GSU_SUCCESS
 		return
 	fi
-	if test "$1" = "complete"; then
-		echo "$gsu_complete_txt"
+	for cmd in "${!_gsu_help_text[@]}"; do
+		[[ "$1" != "$cmd" ]] && continue
+		printf '%s\n' "${_gsu_help_text["$cmd"]}"
 		ret=$GSU_SUCCESS
 		return
-	fi
-	ret=$GSU_SUCCESS
+	done
 	_gsu_get_command_regex "$1"
 	ere="$result"
-	if ! grep -Eq "$ere" $0; then
+	if ! grep -Eq "$ere" "$0"; then
 		_gsu_print_available_commands
 		result="$1"
 		ret=-$E_GSU_BAD_COMMAND
@@ -308,7 +736,8 @@ _com_help()
 			:p
 			p
 		}
-	' $0
+	' "$0"
+	ret=$GSU_SUCCESS
 }
 
 complete_help()
@@ -317,92 +746,7 @@ complete_help()
 	echo "$result"
 }
 
-# Wrapper for the bash getopts builtin.
-#
-# Aborts on programming errors such as missing or invalid option string.  On
-# success $result contains shell code that can be eval'ed. For each defined
-# option x, the local variable o_x will be created when calling eval "$result".
-# o_x contains true/false for options without argument and either the emtpy
-# string or the given argument for options that take an argument.
-#
-# Example:
-# 	gsu_getopts abc:x:y
-# 	eval "$result"
-# 	(($ret < 0)) && return
-#
-# 	[[ "$o_a" = 'true' ]] && echo 'The -a flag was given'
-# 	[[ -n "$o_c" ]] && echo "The -c option was given with arg $o_c"
-gsu_getopts()
-{
-	local i c tab='	' cr='
-'
-
-	gsu_check_arg_count $# 1 1
-	if [[ $ret -lt 0 ]]; then
-		gsu_err_msg
-		exit 1
-	fi
-
-	ret=-$E_GSU_GETOPTS
-	result="invalid optstring $1"
-	if [[ -z "$1" ]] || grep -q '::' <<< "$1" ; then
-		gsu_err_msg
-		exit 1
-	fi
-
-	for ((i=0; i < ${#1}; i++)); do
-		c=${1:$i:1}
-		case "$c" in
-		[a-zA-Z:]);;
-		*)
-			ret=-$E_GSU_GETOPTS
-			result="invalid character $c in optstring"
-			gsu_err_msg
-			exit 1
-		esac
-	done
-	result="local _gsu_getopts_opt"
-	for ((i=0; i < ${#1}; i++)); do
-		c1=${1:$i:1}
-		c2=${1:$(($i + 1)):1}
-		result+=" o_$c1="
-		if [[ "$c2" = ":" ]]; then
-			let i++
-		else
-			result+="false"
-		fi
-	done
-	result+="
-	OPTIND=1
-	while getopts $1 _gsu_getopts_opt \"\$@\"; do
-		case \"\$_gsu_getopts_opt\" in
-"
-	for ((i=0; i < ${#1}; i++)); do
-		c1=${1:$i:1}
-		c2=${1:$(($i + 1)):1}
-		result+="$tab$tab$c1) o_$c1="
-		if [[ "$c2" = ":" ]]; then
-			result+="\"\$OPTARG\""
-			let i++
-		else
-			result+="true"
-		fi
-		result+=";;$cr"
-	done
-	result+="
-		*)
-			ret=-\$E_GSU_GETOPTS
-			result=\"invalid option given\"
-			return
-			;;
-		esac
-	done
-	shift \$((\$OPTIND - 1))
-"
-	ret=$GSU_SUCCESS
-}
-
-_com_complete()
+com_complete()
 {
 	local cmd n cword
 	local -a words
@@ -413,7 +757,12 @@ _com_complete()
 		local -a candidates;
 
 		candidates=(\$($0 complete "\$COMP_CWORD" "\${COMP_WORDS[@]}"));
-		COMPREPLY=(\$(compgen -W "\${candidates[*]}" -- "\$cur"));
+		if ((\$? == 0)); then
+			COMPREPLY=(\$(compgen -W "\${candidates[*]}" -- "\$cur"));
+		else
+			compopt -o filenames;
+			COMPREPLY=(\$(compgen -fd -- "\$cur"));
+		fi
 EOF
 		ret=$GSU_SUCCESS
 		return
@@ -421,8 +770,8 @@ EOF
 
 	cword="$1"
 	gsu_is_a_number "$cword"
-	(($ret < 0)) && return
-	if (($cword <= 1)); then
+	((ret < 0)) && return
+	if ((cword <= 1)); then
 		_gsu_available_commands
 		echo "${result}"
 		ret=$GSU_SUCCESS
@@ -431,9 +780,10 @@ EOF
 	shift
 	words=("$@")
 	cmd="${words[1]}"
-	ret=$GSU_SUCCESS # It's not an error if no completer was defined
-	[[ "$(type -t complete_$cmd)" != "function" ]] && return
-	complete_$cmd "$cword" "${words[@]}"
+	# if no completer is defined for this subcommand we exit unsuccessfully
+	# to let the generic completer above fall back to file name completion.
+	[[ "$(type -t "complete_$cmd")" != "function" ]] && exit 1
+	"complete_$cmd" "$cword" "${words[@]}"
 	# ignore errors, they would only clutter the completion output
 	ret=$GSU_SUCCESS
 }
@@ -449,24 +799,25 @@ EOF
 #
 gsu_cword_is_option_parameter()
 {
-	local opts="$1" cword="$2" prev i n
+	local opts="$1" cword="$2"
+	local opt prev i n
 	local -a words
 
 	result=
-	(($cword == 0)) && return
+	((cword == 0)) && return
 	((${#opts} < 2)) && return
 
 	shift 2
 	words=("$@")
-	prev="${words[$(($cword - 1))]}"
+	prev="${words[$((cword - 1))]}"
 	[[ ! "$prev" == -* ]] && return
 
 	n=$((${#opts} - 1))
 	for ((i=0; i <= $n; i++)); do
 		opt="${opts:$i:1}"
-		[[ "${opts:$(($i + 1)):1}" != ":" ]] && continue
+		[[ "${opts:$((i + 1)):1}" != ":" ]] && continue
 		let i++
-		[[ "$prev" != "-$opt" ]] && continue
+		[[ ! "$prev" =~ ^-.*$opt$ ]] && continue
 		result="$opt"
 		return
 	done
@@ -495,13 +846,13 @@ gsu_get_unnamed_arg_num()
 	shift 2
 	words=("$@")
 	cur="${words[$cword]}"
-	prev="${words[$(($cword - 1))]}"
+	prev="${words[$((cword - 1))]}"
 	result=-1
 	[[ "$cur" == -* ]] && return
 	[[ "$prev" == -* ]] && [[ "$opts" == *${prev#-}:* ]] && return
 
 	for ((i=1; i <= $cword; i++)); do
-		prev="${words[$(($i - 1))]}"
+		prev="${words[$((i - 1))]}"
 		cur="${words[$i]}"
 		[[ "$cur" == -* ]] && continue
 		if [[ "$prev" == -* ]]; then
@@ -511,7 +862,7 @@ gsu_get_unnamed_arg_num()
 		fi
 		let n++
 	done
-	result="$(($n - 1))"
+	result="$((n - 1))"
 }
 
 # Entry point for all gsu-based scripts.
@@ -532,70 +883,25 @@ gsu_get_unnamed_arg_num()
 gsu()
 {
 	local i
-	_gsu_available_commands
-	gsu_cmds="$result"
-	if test $# -eq 0; then
+
+	if (($# == 0)); then
 		_gsu_usage
 		_gsu_print_available_commands
 		exit 1
 	fi
 	arg="$1"
 	shift
-	# check internal commands
-	if [[ "$arg" = "help" || "$arg" = "man" || "$arg" = "prefs" || "$arg" = "complete" ]]; then
-		_com_$arg "$@"
-		if [[ "$ret" -lt 0 ]]; then
+	if [[ "$(type -t "com_$arg")" == 'function' ]]; then
+		"com_$arg" "$@"
+		if ((ret < 0)); then
 			gsu_err_msg
 			exit 1
 		fi
 		exit 0
 	fi
-
-	# external commands
-	for i in $gsu_cmds; do
-		if test "$arg" = "$i"; then
-			com_$arg "$@"
-			if [[ "$ret" -lt 0 ]]; then
-				gsu_err_msg
-				exit 1
-			fi
-			exit 0
-		fi
-	done
-
 	ret=-$E_GSU_BAD_COMMAND
 	result="$arg"
 	gsu_err_msg
-	_gsu_print_available_commands
+	_gsu_print_available_commands 1>&2
 	exit 1
 }
-
-# Check number of arguments.
-#
-# Usage: gsu_check_arg_count <num_given> <num1> [<num2>]
-#
-# Check that <num_given> is between <num1> and <num2> inclusively.
-# If only <num1> ist given, num2 is assumed to be infinity.
-#
-# Examples:
-# 	0 0 no argument allowed
-# 	1 1 exactly one argument required
-# 	0 2 at most two arguments admissible
-# 	2   at least two arguments reqired
-#
-gsu_check_arg_count()
-{
-	ret=-$E_GSU_BAD_ARG_COUNT
-	if [[ $# -eq 2 ]]; then # only num1 is given
-		result="at least $2 args required, $1 given"
-		[[ $1 -lt $2 ]] && return
-		ret=$GSU_SUCCESS
-		return
-	fi
-	# num1 and num2 given
-	result="need at least $2 args, $1 given"
-	[[ $1 -lt $2 ]] && return
-	result="need at most $3 args, $1 given"
-	[[ $1 -gt $3 ]] && return
-	ret=$GSU_SUCCESS
-}