HTTP now automatically encodes jsonvalue content

luprex/core/cpp/json.cpp

@@ -13,6 +13,7 @@
 
 LuaTokenConstant(json_null, "null", "");
 LuaTokenConstant(json_object, "object", "");
+LuaTokenConstant(json_error, "error", "");
 
 static void indent(eng::ostringstream &oss, int level) {
     if (level < NOINDENT_LEVEL) {
@@ -543,23 +544,26 @@ bool decode(LuaStack &LS, LuaSlot out, std::string_view v) {
     lua_State *L = LS.state();
 
     // Try to read a single value from the view.
+    int top = lua_gettop(L);
     bool ok = decode_value(L, v);
     lua_replace(L, out.index());
-    if (!ok) return false;
-
-    // There should be nothing left of the input text.
-    if (v.size() > 0) {
-        lua_pushnil(L);
-        lua_replace(L, out.index());
+    lua_settop(L, top);
+    if (!ok) {
+        LS.set(out, LuaToken("error"));
         return false;
     }
 
-    // Special case: if the top-level result is jsonnull,
-    // then change it to nil.
+    // Special case: if the top level value is 'null', change
+    // it to 'nil.'
     if (LS.istoken(out)) {
         LS.set(out, LuaNil);
     }
 
+    // There should be nothing left of the input text.
+    if (v.size() > 0) {
+        LS.set(out, LuaToken("error"));
+        return false;
+    }
     return true;
 }