jshn: only keep UP_* variables around while they are needed

[project/libubox.git] / sh / jshn.sh

diff --git a/sh/jshn.sh b/sh/jshn.sh
index 9e7f444..78414f0 100644 (file)
--- a/sh/jshn.sh
+++ b/sh/jshn.sh
@@ -23,20 +23,7 @@ __jshn_raw_append() {
 _jshn_append() {
        # var=$1
        local _a_value="$2"
-       local _a_sep="${3:- }"
-       eval "${JSON_PREFIX}$1=\"\${${JSON_PREFIX}$1:+\${${JSON_PREFIX}$1}\${_a_value:+\$_a_sep}}\$_a_value\""
-}
-
-_json_export() {
-       # var=$1
-       # value=$2
-       export -- "${JSON_PREFIX}$1=$2"
-}
-
-_json_add_key() {
-       # var=$1
-       # value=$2
-       _jshn_append "KEYS_$1" "$2"
+       eval "${JSON_PREFIX}$1=\"\${${JSON_PREFIX}$1} \$_a_value\""
 }
 
 _get_var() {
@@ -54,63 +41,58 @@ _set_var() {
 _json_inc() {
        # var=$1
        # dest=$2
-       local _seq
 
-       _json_get_var _seq "$1"
-       _seq="$((${_seq:-0} + 1))"
-       _json_set_var "$1" "$_seq"
-       [ -n "$2" ] && _set_var "$2" "$_seq"
+       let "${JSON_PREFIX}$1 += 1" "$2 = ${JSON_PREFIX}$1"
 }
 
 _json_add_generic() {
        # type=$1
-       local var="$2"
+       # name=$2
        # value=$3
-       local cur="$4"
+       # cur=$4
 
-       [ -n "$cur" ] || _json_get_var cur JSON_CUR
-
-       if [ "${cur%%[0-9]*}" = "JSON_ARRAY" ]; then
-               _json_inc "SEQ_$cur" var
+       local var
+       if [ "${4%%[0-9]*}" = "JSON_ARRAY" ]; then
+               _json_inc "SEQ_$4" var
        else
-               local name="${var//[^a-zA-Z0-9_]/_}"
-               [[ "$name" == "$var" ]] || _json_export "NAME_${cur}_${name}" "$var"
+               local name="${2//[^a-zA-Z0-9_]/_}"
+               [[ "$name" == "$2" ]] || export -- "${JSON_PREFIX}NAME_${4}_${name}=$2"
                var="$name"
        fi
 
        local cur_var=
-       _json_export "${cur}_$var" "$3"
-       _json_export "TYPE_${cur}_$var" "$1"
-       _jshn_append "JSON_UNSET" "${cur}_$var"
-       _json_add_key "$cur" "$var"
+       export -- \
+               "${JSON_PREFIX}${4}_$var=$3" \
+               "${JSON_PREFIX}TYPE_${4}_$var=$1"
+       _jshn_append "JSON_UNSET" "${4}_$var"
+       _jshn_append "KEYS_$4" "$var"
 }
 
 _json_add_table() {
        # name=$1
        # type=$2
        # itype=$3
-       local cur new_cur seq
+       local cur seq
 
        _json_get_var cur JSON_CUR
        _json_inc JSON_SEQ seq
 
        local table="JSON_$3$seq"
        _json_set_var "UP_$table" "$cur"
-       _json_export "KEYS_$table" ""
-       [ "$itype" = "ARRAY" ] && _json_set_var "SEQ_$table" ""
+       export -- "${JSON_PREFIX}KEYS_$table="
+       unset "${JSON_PREFIX}SEQ_$table"
        _json_set_var JSON_CUR "$table"
        _jshn_append "JSON_UNSET" "$table"
 
-       _json_get_var new_cur JSON_CUR
-       _json_add_generic "$2" "$1" "$new_cur" "$cur"
+       _json_add_generic "$2" "$1" "$table" "$cur"
 }
 
 _json_close_table() {
-       local _s_cur _s_new
+       local _s_cur
 
        _json_get_var _s_cur JSON_CUR
-       _json_get_var _s_new "UP_$_s_cur"
-       _json_set_var JSON_CUR "$_s_new"
+       _json_get_var "${JSON_PREFIX}JSON_CUR" "UP_$_s_cur"
+       unset "${JSON_PREFIX}UP_$_s_cur"
 }
 
 json_set_namespace() {
@@ -122,7 +104,7 @@ json_set_namespace() {
 }
 
 json_cleanup() {
-       local unset
+       local unset tmp
 
        _json_get_var unset JSON_UNSET
        for tmp in $unset JSON_VAR; do
@@ -167,25 +149,33 @@ json_close_array() {
 }
 
 json_add_string() {
-       _json_add_generic string "$1" "$2"
+       local cur
+       _json_get_var cur JSON_CUR
+       _json_add_generic string "$1" "$2" "$cur"
 }
 
 json_add_int() {
-       _json_add_generic int "$1" "$2"
+       local cur
+       _json_get_var cur JSON_CUR
+       _json_add_generic int "$1" "$2" "$cur"
 }
 
 json_add_boolean() {
-       _json_add_generic boolean "$1" "$2"
+       local cur
+       _json_get_var cur JSON_CUR
+       _json_add_generic boolean "$1" "$2" "$cur"
 }
 
 json_add_double() {
-       _json_add_generic double "$1" "$2"
+       local cur
+       _json_get_var cur JSON_CUR
+       _json_add_generic double "$1" "$2" "$cur"
 }
 
 # functions read access to json variables
 
 json_load() {
-       eval `jshn -r "$1"`
+       eval "`jshn -r "$1"`"
 }
 
 json_dump() {
@@ -217,10 +207,11 @@ json_get_keys() {
 json_get_values() {
        local _v_dest="$1"
        local _v_keys _v_val _select=
+       local _json_no_warning=1
 
        unset "$_v_dest"
        [ -n "$2" ] && {
-               json_select "$2"
+               json_select "$2" || return 1
                _select=1
        }
 
@@ -242,13 +233,17 @@ json_get_var() {
 
        _json_get_var __cur JSON_CUR
        local __var="${JSON_PREFIX}${__cur}_${2//[^a-zA-Z0-9_]/_}"
-       eval "export -- \"$__dest=\${$__var}\"; [ -n \"\${$__var+x}\" ]"
+       eval "export -- \"$__dest=\${$__var:-$3}\"; [ -n \"\${$__var+x}\${3+x}\" ]"
 }
 
 json_get_vars() {
        while [ "$#" -gt 0 ]; do
                local _var="$1"; shift
-               json_get_var "$_var" "$_var"
+               if [ "$_var" != "${_var#*:}" ]; then
+                       json_get_var "${_var%%:*}" "${_var%%:*}" "${_var#*:}"
+               else
+                       json_get_var "$_var" "$_var"
+               fi
        done
 }
 
@@ -264,6 +259,7 @@ json_select() {
        [[ "$1" == ".." ]] && {
                _json_get_var cur JSON_CUR
                _json_get_var cur "UP_$cur"
+               unset "${JSON_PREFIX}UP_$cur"
                _json_set_var JSON_CUR "$cur"
                return 0
        }
@@ -271,10 +267,12 @@ json_select() {
        case "$type" in
                object|array)
                        json_get_var cur "$target"
+                       _json_get_var "${JSON_PREFIX}UP_$cur" JSON_CUR
                        _json_set_var JSON_CUR "$cur"
                ;;
                *)
-                       echo "WARNING: Variable '$target' does not exist or is not an array/object"
+                       [ -n "$_json_no_warning" ] || \
+                               echo "WARNING: Variable '$target' does not exist or is not an array/object"
                        return 1
                ;;
        esac