problem about send_bs_remain

[zhangjinus]

when sending multi-frame, tp_poll handle remain packets. but in isotp_send_with_id function，send_bs_remain set to 0, causing tp_poll can not do sending. link->send_status will stay in ISOTP_SEND_STATUS_INPROGRESS.
/* send multi-frame */
ret = isotp_send_first_frame(link, id);
if (ISOTP_RET_OK == ret) {
link->send_bs_remain = 0;
link->send_st_min = 0;
link->send_wtf_count = 0;
link->send_timer_st = link->isotp_user_get_ms();
link->send_timer_bs = link->isotp_user_get_ms() + ISO_TP_DEFAULT_RESPONSE_TIMEOUT;
link->send_protocol_result = ISOTP_PROTOCOL_RESULT_OK;
link->send_status = ISOTP_SEND_STATUS_INPROGRESS;
}
....
void isotp_poll(IsoTpLink *link) {
int ret;

/* only polling when operation in progress */
if (ISOTP_SEND_STATUS_INPROGRESS == link->send_status) {

    /* continue send data */
    if (/* send data if bs_remain is invalid or bs_remain large than zero */
    **(ISOTP_INVALID_BS == link->send_bs_remain || link->send_bs_remain > 0)** &&
    /* and if st_min is zero or go beyond interval time */
    (0 == link->send_st_min || (0 != link->send_st_min && IsoTpTimeAfter(link->isotp_user_get_ms(), link->send_timer_st)))) {
        
        ret = isotp_send_consecutive_frame(link);

......

[prj]

When you initiate a send, then link status gets set to ISOTP_SEND_STATUS_INPROGRESS.
This never changes unless it fails (ERROR) or completes (IDLE).

So not sure where you see a problem.

There is a check before:

if (ISOTP_SEND_STATUS_INPROGRESS == link->send_status) {
    isotp_user_debug("Abort previous message, transmission in progress.\n");
    return ISOTP_RET_INPROGRESS;
}