From ee39f37ff22194ed45ec5d470f36b52f316d98d9 Mon Sep 17 00:00:00 2001
From: Andre Noll <maan@systemlinux.org>
Date: Wed, 10 Jun 2009 16:48:47 +0200
Subject: [PATCH] Priliminary version of gsu2.

Backwards compatible, new features are only used by dpch yet.
---
 funcs/gsu | 154 +++++++++++++++++++++++++++++++++++++++---------------
 1 file changed, 112 insertions(+), 42 deletions(-)

diff --git a/funcs/gsu b/funcs/gsu
index 9611b30..81066f7 100644
--- a/funcs/gsu
+++ b/funcs/gsu
@@ -10,6 +10,11 @@ E_GSU_BAD_COMMAND		invalid command
 E_GSU_NOT_A_NUMBER		not a number
 E_GSU_SOURCE			error in config file
 E_GSU_CONFIG			bad/missing config file option
+E_GSU_BAD_CONFIG_VAR		invalid config variable
+E_GSU_NEED_VALUE		value required but not given
+E_GSU_BAD_BOOL			bad value for boolian option
+E_GSU_BAD_OPTION_TYPE		invalid option type
+E_NO_DEFAULT			missing default value
 $gsu_errors
 "
 	local a b i=0
@@ -100,7 +105,7 @@ export -f _gsu_usage
 
 _gsu_available_commands()
 {
-	result="$( (printf "help\nman\n"; grep "^com_[a-z_]\+()" $0) \
+	result="$( (printf "help\nman\nprefs\n"; grep "^com_[a-z_]\+()" $0) \
 		| sed -e 's/^com_//' -e 's/()//' \
 		| sort \
 		| tr '\n' ' ')"
@@ -129,6 +134,42 @@ _gsu_print_available_commands()
 }
 export -f _gsu_print_available_commands
 
+export gsu_prefs_txt="
+Print the current preferences.
+
+Usage: prefs
+
+Print out a list of all cmt config variables, together with their current value
+and the default value."
+com_prefs()
+{
+	local i
+
+	for ((i=0; i < ${#gsu_options[@]}; i++)); do
+		local name= option_type= default_value= required=
+		local description= help_text=
+		eval "${gsu_options[$i]}"
+		eval val='"$'${gsu_name}_$name'"'
+		case "$required" in
+		true|yes)
+			printf "# required"
+			;;
+		*)
+			printf "# optional"
+			;;
+		esac
+		printf " $option_type: $description"
+		if [[ "$required" != "yes" && "$required" != "true" ]]; then
+			printf " [$default_value]"
+		fi
+		echo
+		printf "$name=$val"
+		[[ "$val" == "$default_value" ]] && printf " # default"
+		echo
+	done
+}
+export -f com_prefs
+
 export gsu_man_txt="
 Print the manual.
 
@@ -190,6 +231,7 @@ com_help()
 		# sed is magic, baby
 		(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 "--"
 
 		grep -A 2 "^com_\([a-zA-Z_0-9]\+\)()" $0) \
 			| grep -v -- '--' \
@@ -221,6 +263,11 @@ com_help()
 		ret=$GSU_SUCCESS
 		return
 	fi
+	if test "$1" = "prefs"; then
+		echo "$gsu_prefs_txt"
+		ret=$GSU_SUCCESS
+		return
+	fi
 	ret=$GSU_SUCCESS
 	if grep -q "^com_$1()" $0; then
 		sed -e "1,/com_$1()/d" -e '/^{/,$d' -e 's/^## *//' $0
@@ -232,51 +279,68 @@ com_help()
 }
 export -f com_help
 
-_gsu_init_config()
+# internal gsu function that syntactically checks the gsu_options array
+# for errors and parses the config file.
+_gsu_check_options()
 {
-	local name val default_val required ty comment
+	local i conf="${gsu_config_file:=$HOME/.$gsu_name.rc}"
 
-	# set default values
-	while read name default_val required ty comment; do
-		if test -z "$name"; then
-			continue
-		fi
-		eval ${gsu_self}_$name="$default_val"
-	done << EOF
-	$gsu_config_vars
-EOF
-	result="$HOME/.${gsu_self}rc"
-	# overwrite by custom configuration
-	if [ -r "$result" ]; then
-		ret=-$E_GSU_SOURCE
-		if ! . "$result"; then
-			gsu_err_msg
-			exit 1
-		fi
-	fi
-	while read name default_val required ty comment; do
-		[ -z "$name" ] && continue
-		eval val="\$$name"
-		# abort if any required config var remains unset
-		ret=-$_E_GSU_CONFIG
-		if [ "$val" = "-" -a "$required" = "required" ]; then
+	[[ -r "$conf" ]] && source "$conf"
+
+	for ((i=0; i < ${#gsu_options[@]}; i++)); do
+		local name= option_type= default_value= required=
+		local description= help_text=
+		local val
+
+		eval "${gsu_options[$i]}"
+
+		# Check name. It must be non-empty and consist of [a-zA-Z_0-9]
+		# only.  Moreover it must not start with [a-zA-Z].
+
+		ret=-$E_GSU_BAD_CONFIG_VAR
+		result="$name"
+		# bash's =~ works only for 3.2 and newer, so use grep
+		echo "$name" | grep '^[a-zA-Z][a-zA-Z_0123456789]*$' &> /dev/null;
+		[[ $? -ne 0 ]] && return
+
+		eval val='"'\$$name'"'
+		case "$required" in
+		true|yes)
+			ret=-$E_GSU_NEED_VALUE
 			result="$name"
-			gsu_err_msg
-			exit 1
-		fi
-		if [ $ty == "number" ]; then
+			[[ -z "$val" ]] && return
+			;;
+		false|no)
+			ret=-$E_NO_DEFAULT
+			result="$name"
+			[[ -z "$default_value" ]] && return
+			;;
+		*)
+			ret=-$E_GSU_BAD_BOOL
+			result="required: $required, name: $name, val: $val"
+			return
+		esac
+
+		eval ${gsu_name}_$name='"'${val:=$default_value}'"'
+
+		# Check option type. ATM, only num and string are supported
+		# Other types may be added without breaking compatibility
+		case "$option_type" in
+		string)
+			;;
+		num)
 			gsu_is_a_number "$val"
-			if [ $ret -lt 0];  then
-				gsu_err_msg
-				exit 1
-			fi
-		fi
-		eval export ${gsu_self}_$name
-	done << EOF
-	$config_vars
-EOF
+			[[ $ret -lt 0 ]] && return
+			;;
+		*)
+			ret=-$E_BAD_OPTION_TYPE
+			result="$name/$option_type"
+			return
+		esac
+	done
+	ret=$GSU_SUCCESS
 }
-export -f _gsu_init_config
+export -f _gsu_check_options
 
 gsu()
 {
@@ -284,7 +348,11 @@ gsu()
 
 	_gsu_self="$(basename $0)"
 	_gsu_init_errors
-	_gsu_init_config
+	_gsu_check_options
+	if [[ "$ret" -lt 0 ]]; then
+		gsu_err_msg
+		exit 1
+	fi
 	_gsu_available_commands
 	gsu_cmds="$result"
 	if test $# -eq 0; then
@@ -311,3 +379,5 @@ gsu()
 	exit 1
 }
 export -f gsu
+
+# TODO: gsu_strerror: get error string
-- 
2.30.2