+/* process bchannel export/import message from join */
+void message_bchannel_from_join(class JoinRemote *joinremote, int type, unsigned long handle)
+{
+ class Endpoint *epoint;
+ class Port *port;
+ class PmISDN *isdnport;
+ struct mISDNport *mISDNport;
+ int i, ii;
+
+ switch(type)
+ {
+ case BCHANNEL_REQUEST:
+ /* find the port object for the join object ref */
+ if (!(epoint = find_epoint_id(joinremote->j_epoint_id)))
+ {
+ PDEBUG(DEBUG_BCHANNEL, "join %d has no endpoint (anymore)\n", joinremote->j_serial);
+ return;
+ }
+ if (!epoint->ep_portlist)
+ {
+ PDEBUG(DEBUG_BCHANNEL, "join %d has no port (anymore in portlist)\n", joinremote->j_serial);
+ return;
+ }
+ if (epoint->ep_portlist->next)
+ {
+ PERROR("join %d has enpoint %d with more than one port. this shall not happen to remote joins.\n", joinremote->j_serial, epoint->ep_serial);
+ }
+ if (!(port = find_port_id(epoint->ep_portlist->port_id)))
+ {
+ PDEBUG(DEBUG_BCHANNEL, "join %d has no port (anymore as object)\n", joinremote->j_serial);
+ return;
+ }
+ if (!((port->p_type&PORT_CLASS_MASK) != PORT_CLASS_mISDN))
+ {
+ PERROR("join %d has port %d not of mISDN type. This shall not happen.\n", joinremote->j_serial, port->p_serial);
+ }
+ isdnport = (class PmISDN *)port;
+
+ /* assign */
+ if (isdnport->p_m_remote_id)
+ {
+ PERROR("join %d recevied bchannel request from remote, but channel is already assinged.\n", joinremote->j_serial);
+ break;
+ }
+ mISDNport = isdnport->p_m_mISDNport;
+ i = isdnport->p_m_b_index;
+ chan_trace_header(mISDNport, isdnport, "MESSAGE_BCHANNEL (from remote application)", DIRECTION_NONE);
+ add_trace("type", NULL, "export request");
+ isdnport->p_m_remote_ref = joinremote->j_serial;
+ isdnport->p_m_remote_id = joinremote->j_remote_id;
+ if (mISDNport && i>=0)
+ {
+ bchannel_event(mISDNport, i, B_EVENT_EXPORTREQUEST);
+ }
+ end_trace();
+ break;
+
+ case BCHANNEL_ASSIGN_ACK:
+ case BCHANNEL_REMOVE_ACK:
+ /* find mISDNport for stack ID */
+ mISDNport = mISDNport_first;
+ while(mISDNport)
+ {
+ i = 0;
+ ii = mISDNport->b_num;
+ while(i < ii)
+ {
+#ifdef SOCKET_MISDN
+ if ((unsigned long)(mISDNport->portnum<<8)+i+1+(i>=15) == handle)
+#else
+ if (mISDNport->b_addr[i] == handle)
+#endif
+ break;
+ i++;
+ }
+ if (i != ii)
+ break;
+ mISDNport = mISDNport->next;
+ }
+ if (!mISDNport)
+ {
+ PERROR("received assign/remove ack for bchannel's handle=%x, but handle does not exist in any mISDNport structure.\n", handle);
+ break;
+ }
+ /* mISDNport may now be set or NULL */
+
+ /* set */
+ chan_trace_header(mISDNport, mISDNport->b_port[i], "MESSAGE_BCHANNEL (from remote application)", DIRECTION_NONE);
+ add_trace("type", NULL, (type==BCHANNEL_ASSIGN_ACK)?"assign_ack":"remove_ack");
+ if (mISDNport && i>=0)
+ bchannel_event(mISDNport, i, (type==BCHANNEL_ASSIGN_ACK)?B_EVENT_EXPORTED:B_EVENT_IMPORTED);
+ end_trace();
+ break;
+ default:
+ PERROR("received wrong bchannel message type %d from remote\n", type);
+ }
+}
+
+
+/*
+ * handler
+
+audio transmission procedure:
+-----------------------------
+
+* priority
+three sources of audio transmission:
+- crypto-data high priority
+- tones high priority (also high)
+- remote-data low priority
+
+* elapsed
+a variable that temporarily shows the number of samples elapsed since last transmission process.
+p_m_last_tv_* is used to store that last timestamp. this is used to calculate the time elapsed.
+
+* load
+a variable that is increased whenever data is transmitted.
+it is decreased while time elapses. it stores the number of samples that
+are currently loaded to dsp module.
+since clock in dsp module is the same clock for user space process, these
+times have no skew.
+
+* levels
+there are two levels:
+ISDN_LOAD will give the load that have to be kept in dsp.
+ISDN_MAXLOAD will give the maximum load before dropping.
+
+* procedure for low priority data
+see txfromup() for procedure
+in short: remote data is ignored during high priority tones
+
+* procedure for high priority data
+whenever load is below ISDN_LOAD, load is filled up to ISDN_LOAD
+if no more data is available, load becomes empty again.
+
+'load' variable:
+0 ISDN_LOAD ISDN_MAXLOAD
++--------------------+----------------------+
+| | |
++--------------------+----------------------+
+
+on empty load or on load below ISDN_LOAD, the load is inceased to ISDN_LOAD:
+0 ISDN_LOAD ISDN_MAXLOAD
++--------------------+----------------------+
+|TTTTTTTTTTTTTTTTTTTT| |
++--------------------+----------------------+
+
+on empty load, remote-audio causes the load with the remote audio to be increased to ISDN_LOAD.
+0 ISDN_LOAD ISDN_MAXLOAD
++--------------------+----------------------+
+|TTTTTTTTTTTTTTTTTTTTRRRRR |
++--------------------+----------------------+
+
+ */
+int PmISDN::handler(void)
+{
+ struct lcr_msg *message;
+ int elapsed = 0;
+ int ret;
+
+ if ((ret = Port::handler()))
+ return(ret);
+
+ /* get elapsed */
+ if (p_m_last_tv_sec)
+ {
+ elapsed = 8000 * (now_tv.tv_sec - p_m_last_tv_sec)
+ + 8 * (now_tv.tv_usec/1000 - p_m_last_tv_msec);
+ } else
+ {
+ /* set clock of first process ever in this instance */
+ p_m_last_tv_sec = now_tv.tv_sec;
+ p_m_last_tv_msec = now_tv.tv_usec/1000;
+ }
+ /* process only if we have a minimum of samples, to make packets not too small */
+ if (elapsed >= ISDN_TRANSMIT)
+ {
+ /* set clock of last process! */
+ p_m_last_tv_sec = now_tv.tv_sec;
+ p_m_last_tv_msec = now_tv.tv_usec/1000;
+
+ /* update load */
+ if (elapsed < p_m_load)
+ p_m_load -= elapsed;
+ else
+ p_m_load = 0;
+
+ /* to send data, tone must be active OR crypt messages must be on */
+ if ((p_tone_name[0] || p_m_crypt_msg_loops)
+ && (p_m_load < ISDN_LOAD)
+ && (p_state==PORT_STATE_CONNECT || p_m_mISDNport->tones))
+ {
+ int tosend = ISDN_LOAD - p_m_load, length;
+#ifdef SOCKET_MISDN
+ unsigned char buf[MISDN_HEADER_LEN+tosend];
+ struct mISDNhead *frm = (struct mISDNhead *)buf;
+ unsigned char *p = buf+MISDN_HEADER_LEN;
+#else
+ unsigned char buf[mISDN_HEADER_LEN+tosend];
+ iframe_t *frm = (iframe_t *)buf;
+ unsigned char *p = buf+mISDN_HEADER_LEN;
+#endif
+
+ /* copy crypto loops */
+ while (p_m_crypt_msg_loops && tosend)
+ {
+ /* how much do we have to send */
+ length = p_m_crypt_msg_len - p_m_crypt_msg_current;
+
+ /* clip tosend */
+ if (length > tosend)
+ length = tosend;
+
+ /* copy message (part) to buffer */
+ memcpy(p, p_m_crypt_msg+p_m_crypt_msg_current, length);
+
+ /* new position */
+ p_m_crypt_msg_current += length;
+ if (p_m_crypt_msg_current == p_m_crypt_msg_len)
+ {
+ /* next loop */
+ p_m_crypt_msg_current = 0;
+ p_m_crypt_msg_loops--;
+// puts("eine loop weniger");
+ }
+
+ /* new length */
+ tosend -= length;
+ }
+
+ /* copy tones */
+ if (p_tone_name[0] && tosend)
+ {
+ tosend -= read_audio(p, tosend);
+ }
+
+ /* send data */
+#ifdef SOCKET_MISDN
+ frm->prim = DL_DATA_REQ;
+ frm->id = 0;
+ ret = sendto(p_m_mISDNport->b_socket[p_m_b_index], buf, MISDN_HEADER_LEN+ISDN_LOAD-p_m_load-tosend, 0, NULL, 0);
+ if (!ret)
+ PERROR("Failed to send to socket %d\n", p_m_mISDNport->b_socket[p_m_b_index]);
+#else
+ frm->prim = DL_DATA | REQUEST;
+ frm->addr = p_m_mISDNport->b_addr[p_m_b_index] | FLG_MSG_DOWN;
+ frm->dinfo = 0;
+ frm->len = ISDN_LOAD - p_m_load - tosend;
+ if (frm->len)
+ mISDN_write(mISDNdevice, frm, mISDN_HEADER_LEN+frm->len, TIMEOUT_1SEC);
+#endif
+ p_m_load += ISDN_LOAD - p_m_load - tosend;
+ }
+ }