jshn: refactor _jshn_append to require fewer evals

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

diff --git a/sh/jshn.sh b/sh/jshn.sh
index 93fbec2..9e7f444 100644 (file)
--- a/sh/jshn.sh
+++ b/sh/jshn.sh
@@ -1,77 +1,71 @@
 # functions for parsing and generating json
 
 _json_get_var() {
-       local ___dest="$1"
-       local ___var="$2"
-       eval "$___dest=\"\$${JSON_PREFIX}$___var\""
+       # dest=$1
+       # var=$2
+       eval "$1=\"\$${JSON_PREFIX}$2\""
 }
 
 _json_set_var() {
-       local ___var="$1"
+       # var=$1
        local ___val="$2"
-       eval "${JSON_PREFIX}$___var=\"\$___val\""
+       eval "${JSON_PREFIX}$1=\"\$___val\""
 }
 
 __jshn_raw_append() {
-       local var="$1"
+       # var=$1
        local value="$2"
        local sep="${3:- }"
 
-       eval "export -- \"$var=\${$var:+\${$var}\${value:+\$sep}}\$value\""
+       eval "export -- \"$1=\${$1:+\${$1}\${value:+\$sep}}\$value\""
 }
 
-
 _jshn_append() {
-       local __var="$1"
-       local __value="$2"
-       local __sep="${3:- }"
-       local __old_val
-
-       _json_get_var __old_val "$__var"
-       __value="${__old_val:+$__old_val$__sep}$__value"
-       _json_set_var "$__var" "$__value"
+       # 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() {
-       local __var="${JSON_PREFIX}$1"
-       local __val="$2"
-
-       export -- "$__var=$__val"
+       # var=$1
+       # value=$2
+       export -- "${JSON_PREFIX}$1=$2"
 }
 
 _json_add_key() {
-       local table="$1"
-       local var="$2"
-       _jshn_append "KEYS_${table}" "$var"
+       # var=$1
+       # value=$2
+       _jshn_append "KEYS_$1" "$2"
 }
 
 _get_var() {
-       local __dest="$1"
-       local __var="$2"
-       eval "$__dest=\"\$$__var\""
+       # var=$1
+       # value=$2
+       eval "$1=\"\$$2\""
 }
 
 _set_var() {
-       local __var="$1"
+       # var=$1
        local __val="$2"
-       eval "$__var=\"\$__val\""
+       eval "$1=\"\$__val\""
 }
 
 _json_inc() {
-       local _var="$1"
-       local _dest="$2"
+       # var=$1
+       # dest=$2
        local _seq
 
-       _json_get_var _seq "$_var"
+       _json_get_var _seq "$1"
        _seq="$((${_seq:-0} + 1))"
-       _json_set_var "$_var" "$_seq"
-       [ -n "$_dest" ] && _set_var "$_dest" "$_seq"
+       _json_set_var "$1" "$_seq"
+       [ -n "$2" ] && _set_var "$2" "$_seq"
 }
 
 _json_add_generic() {
-       local type="$1"
+       # type=$1
        local var="$2"
-       local val="$3"
+       # value=$3
        local cur="$4"
 
        [ -n "$cur" ] || _json_get_var cur JSON_CUR
@@ -84,23 +78,23 @@ _json_add_generic() {
                var="$name"
        fi
 
-       _json_export "${cur}_$var" "$val"
-       _json_export "TYPE_${cur}_$var" "$type"
+       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"
 }
 
 _json_add_table() {
-       local name="$1"
-       local type="$2"
-       local itype="$3"
-       local cur new_cur
-       local seq
+       # name=$1
+       # type=$2
+       # itype=$3
+       local cur new_cur seq
 
        _json_get_var cur JSON_CUR
        _json_inc JSON_SEQ seq
 
-       local table="JSON_$itype$seq"
+       local table="JSON_$3$seq"
        _json_set_var "UP_$table" "$cur"
        _json_export "KEYS_$table" ""
        [ "$itype" = "ARRAY" ] && _json_set_var "SEQ_$table" ""
@@ -108,7 +102,7 @@ _json_add_table() {
        _jshn_append "JSON_UNSET" "$table"
 
        _json_get_var new_cur JSON_CUR
-       _json_add_generic "$type" "$1" "$new_cur" "$cur"
+       _json_add_generic "$2" "$1" "$new_cur" "$cur"
 }
 
 _json_close_table() {
@@ -152,7 +146,6 @@ json_init() {
        export -- \
                ${JSON_PREFIX}JSON_SEQ=0 \
                ${JSON_PREFIX}JSON_CUR="JSON_VAR" \
-               ${JSON_PREFIX}JSON_UNSET="" \
                ${JSON_PREFIX}KEYS_JSON_VAR= \
                ${JSON_PREFIX}TYPE_JSON_VAR=
 }