jshn: get rid of the table stack, use the UP_* variable instead to speed up processing

Signed-off-by: Felix Fietkau <nbd@openwrt.org>

diff --git a/sh/jshn.sh b/sh/jshn.sh
index efac0af..3aff5ea 100644 (file)
--- a/sh/jshn.sh
+++ b/sh/jshn.sh
@@ -68,15 +68,6 @@ _json_inc() {
        [ -n "$_dest" ] && _set_var "$_dest" "$_seq"
 }
 
-_json_stack_push() {
-       local new_cur="$1"
-       local cur
-
-       _json_get_var cur JSON_CUR
-       _jshn_append JSON_STACK "$cur"
-       _json_set_var JSON_CUR "$new_cur"
-}
-
 _json_add_generic() {
        local type="$1"
        local var="$2"
@@ -110,10 +101,10 @@ _json_add_table() {
        _json_inc JSON_SEQ seq
 
        local table="JSON_$itype$seq"
-       _json_export "UP_$table" "$cur"
+       _json_set_var "UP_$table" "$cur"
        _json_export "KEYS_$table" ""
        [ "$itype" = "ARRAY" ] && _json_export "SEQ_$table" ""
-       _json_stack_push "$table"
+       _json_set_var JSON_CUR "$table"
        _jshn_append "JSON_UNSET" "$table"
 
        _json_get_var new_cur JSON_CUR
@@ -121,13 +112,11 @@ _json_add_table() {
 }
 
 _json_close_table() {
-       local stack new_stack
+       local _s_cur _s_new
 
-       _json_get_var stack JSON_STACK
-       _json_set_var JSON_CUR "${stack##* }"
-       new_stack="${stack% *}"
-       [[ "$stack" == "$new_stack" ]] && new_stack=
-       _json_set_var JSON_STACK "$new_stack"
+       _json_get_var _s_cur JSON_CUR
+       _json_get_var _s_new "UP_$_s_cur"
+       _json_set_var JSON_CUR "$_s_new"
 }
 
 json_set_namespace() {
@@ -154,7 +143,6 @@ json_cleanup() {
 
        unset \
                ${JSON_PREFIX}JSON_SEQ \
-               ${JSON_PREFIX}JSON_STACK \
                ${JSON_PREFIX}JSON_CUR \
                ${JSON_PREFIX}JSON_UNSET
 }
@@ -163,7 +151,6 @@ json_init() {
        json_cleanup
        export -- \
                ${JSON_PREFIX}JSON_SEQ=0 \
-               ${JSON_PREFIX}JSON_STACK= \
                ${JSON_PREFIX}JSON_CUR="JSON_VAR" \
                ${JSON_PREFIX}JSON_UNSET="" \
                ${JSON_PREFIX}KEYS_JSON_VAR= \