求助：哪位用过webnet处理解析web端下发的json数据？

tih_gw_paracfg = function() {
    var txd = {
        "rid": "gwSet",
        "prokey": $("#productkey").val(), 
        "devname": $("#devicename").val(), 
        "devsec": $("#devicesecret").val()
    };
    tih_txhttp(txd);
};
tih_txhttp = function(txd) {
    $.get("/cgi-bin/tihcfg", txd, tih_rxhttp, "JSON");
};

static void cgi_tihcfg_handler(struct webnet_session* session)
{
    const char* mimetype;
    struct webnet_request* request;
    const char *reqflag,*prokey,*devname,*devsec,*reqflag2;
    cJSON *root,*subroot;
    gwdata *gwdata_t = RT_NULL;
    loradata *loradata_t = RT_NULL;
    char *buff;
    RT_ASSERT(session != RT_NULL);
    request = session->request;
    RT_ASSERT(request != RT_NULL);
    /* get mimetype */
//    mimetype = mime_get_type(".xml");
    session->request->result_code = 200;
//    webnet_session_set_header(session, mimetype, 200, "Ok", -1);
    webnet_session_set_header(session, "application/json", 200, "Ok", -1);
    reqflag = webnet_request_get_query(request, "rid");
//    reqflag2 = webnet_request_get_query(request, "devname");
    rt_kprintf("-> cgi_tihcfg_handler - reqflag = %s\n",reqflag);
//    rt_kprintf("-> cgi_tihcfg_handler - reqflag2 = %s\n",reqflag2);
....
}