nua_session.c

Sofia SIP is an open-source SIP User-Agent library, compliant with the IETF RFC3261 specification.

    ss->ss_update_needed = ss->ss_100rel = 1;

  if (nh->nh_soa) {
    soa_init_offer_answer(nh->nh_soa);

    if (sip->sip_payload)
      offer_sent = 0;		/* XXX - kludge */
    else if (soa_generate_offer(nh->nh_soa, 0, NULL) < 0)
      return -1;
    else
      offer_sent = 1;

    if (offer_sent > 0 &&
	session_include_description(nh->nh_soa, 1, msg, sip) < 0)
      return nua_client_return(cr, 900, "Internal media error", msg);

    if (NH_PGET(nh, media_features) &&
	!nua_dialog_is_established(nh->nh_ds) &&
	!sip->sip_accept_contact && !sip->sip_reject_contact) {
      sip_accept_contact_t ac[1];
      sip_accept_contact_init(ac);

      ac->cp_params = (msg_param_t *)
	soa_media_features(nh->nh_soa, 1, msg_home(msg));

      if (ac->cp_params) {
	msg_header_replace_param(msg_home(msg), ac->cp_common, "explicit");
	sip_add_dup(msg, sip, (sip_header_t *)ac);
      }
    }
  }
  else {
    offer_sent = session_get_description(sip, NULL, NULL);
  }

  retval = nua_base_client_trequest(cr, msg, sip,
				    NTATAG_REL100(ss->ss_100rel),
				    TAG_NEXT(tags));
  if (retval == 0) {
    if ((cr->cr_offer_sent = offer_sent))
      ss->ss_oa_sent = Offer;

    if (!cr->cr_restarting) /* Restart logic calls nua_invite_client_report */
      signal_call_state_change(nh, ss, 0, "INVITE sent", 
			       nua_callstate_calling);
  }

  return retval;
}

static int nua_invite_client_response(nua_client_request_t *cr,
				      int status, char const *phrase,
				      sip_t const *sip)
{
  nua_dialog_usage_t *du = cr->cr_usage;
  nua_session_usage_t *ss = nua_dialog_usage_private(du);

  if (ss == NULL || sip == NULL) {
    /* Xyzzy */
  }
  else if (status < 300) {
    du->du_ready = 1;

    if (session_timer_is_supported(ss->ss_timer))
      session_timer_store(ss->ss_timer, sip);

    session_timer_set(ss);
  }
  
  return nua_session_client_response(cr, status, phrase, sip);
}

static int nua_invite_client_preliminary(nua_client_request_t *cr,
					 int status, char const *phrase,
					 sip_t const *sip)
{
  nua_handle_t *nh = cr->cr_owner;
  nua_dialog_usage_t *du = cr->cr_usage;
  nua_session_usage_t *ss = nua_dialog_usage_private(du);

  assert(sip);

  if (ss && sip && sip->sip_rseq) {
    /* Handle 100rel responses */
    sip_rseq_t *rseq = sip->sip_rseq;

    /* Establish early dialog - we should fork here */
    if (!nua_dialog_is_established(nh->nh_ds)) {
      nta_outgoing_t *tagged;

      nua_dialog_uac_route(nh, nh->nh_ds, sip, 1);
      nua_dialog_store_peer_info(nh, nh->nh_ds, sip);
      
      /* Tag the INVITE request */
      tagged = nta_outgoing_tagged(cr->cr_orq,
				   nua_client_orq_response, cr,
				   sip->sip_to->a_tag, sip->sip_rseq);
      if (tagged) {
	nta_outgoing_destroy(cr->cr_orq), cr->cr_orq = tagged;
      }
      else {
	cr->cr_graceful = 1;
	ss->ss_reason = "SIP;cause=500;text=\"Cannot Create Early Dialog\"";
      }
    }
  
    if (!rseq) {
      SU_DEBUG_5(("nua(%p): 100rel missing RSeq\n", (void *)nh));
    }
    else if (nta_outgoing_rseq(cr->cr_orq) > rseq->rs_response) {
      SU_DEBUG_5(("nua(%p): 100rel bad RSeq %u (got %u)\n", (void *)nh, 
		  (unsigned)rseq->rs_response,
		  nta_outgoing_rseq(cr->cr_orq)));
      return 1;    /* Do not send event */
    }
    else if (nta_outgoing_setrseq(cr->cr_orq, rseq->rs_response) < 0) {
      SU_DEBUG_1(("nua(%p): cannot set RSeq %u\n", (void *)nh, 
		  (unsigned)rseq->rs_response));
      cr->cr_graceful = 1;
      ss->ss_reason = "SIP;cause=400;text=\"Bad RSeq\"";
    }
  }

  return nua_session_client_response(cr, status, phrase, sip);
}

/** Process response to a session request (INVITE, PRACK, UPDATE) */
static int nua_session_client_response(nua_client_request_t *cr,
				       int status, char const *phrase,
				       sip_t const *sip)
{
  nua_handle_t *nh = cr->cr_owner;
  nua_dialog_usage_t *du = cr->cr_usage;
  nua_session_usage_t *ss = nua_dialog_usage_private(du);

  char const *sdp = NULL;
  size_t len;
  char const *received = NULL;

#define LOG3(m) \
  SU_DEBUG_3(("nua(%p): %s: %s %s in %u %s\n", \
	      (void *)nh, cr->cr_method_name, (m), \
	      received ? received : "SDP", status, phrase))
#define LOG5(m) \
  SU_DEBUG_5(("nua(%p): %s: %s %s in %u %s\n", \
	      (void *)nh, cr->cr_method_name, (m), received, status, phrase))

  if (!ss || !sip || 300 <= status)
    /* Xyzzy */;
  else if (!session_get_description(sip, &sdp, &len))
    /* No SDP */;
  else if (cr->cr_answer_recv) {
    /* Ignore spurious answers after completing O/A */
    LOG3("ignoring duplicate");
    sdp = NULL;
  }
  else if (cr->cr_offer_sent) {
    /* case 1: answer to our offer */
    cr->cr_answer_recv = status;
    received = Answer;

    if (nh->nh_soa == NULL)
      LOG5("got SDP");
    else if (soa_set_remote_sdp(nh->nh_soa, NULL, sdp, len) < 0) {
      LOG3("error parsing SDP");
      sdp = NULL;
      cr->cr_graceful = 1;
      ss->ss_reason = "SIP;cause=400;text=\"Malformed Session Description\"";
    }
    else if (soa_process_answer(nh->nh_soa, NULL) < 0) {
      LOG5("error processing SDP");
      /* XXX */
      sdp = NULL;
    }
    else if (soa_activate(nh->nh_soa, NULL) < 0)
      /* XXX - what about errors? */
      LOG3("error activating media after");
    else
      LOG5("processed SDP");
  }
  else if (cr->cr_method != sip_method_invite) {
    /* If non-invite request did not have offer, ignore SDP in response */
    LOG3("ignoring extra");
    sdp = NULL;
  }
  else {
    /* case 2: new offer */
    cr->cr_offer_recv = 1, cr->cr_answer_sent = 0;
    received = Offer;

    if (nh->nh_soa && soa_set_remote_sdp(nh->nh_soa, NULL, sdp, len) < 0) {
      LOG3("error parsing SDP");
      sdp = NULL;
      cr->cr_graceful = 1;
      ss->ss_reason = "SIP;cause=400;text=\"Malformed Session Description\"";
    }
    else 
      LOG5("got SDP");
  }

  if (ss && received)
    ss->ss_oa_recv = received;

  if (sdp && nh->nh_soa)
    return nua_base_client_tresponse(cr, status, phrase, sip,
				     NH_REMOTE_MEDIA_TAGS(1, nh->nh_soa),
				     TAG_END());
  else
    return nua_base_client_response(cr, status, phrase, sip, NULL);
}

static int nua_invite_client_report(nua_client_request_t *cr,
				    int status, char const *phrase,
				    sip_t const *sip,
				    nta_outgoing_t *orq,
				    tagi_t const *tags)
{
  nua_handle_t *nh = cr->cr_owner;
  nua_dialog_state_t *ds = nh->nh_ds;
  nua_dialog_usage_t *du = cr->cr_usage;
  nua_session_usage_t *ss = nua_dialog_usage_private(du);
  unsigned next_state;
  int error;

  nh_referral_respond(nh, status, phrase); /* XXX - restarting after 401/407 */

  nua_stack_event(nh->nh_nua, nh, 
		  nta_outgoing_getresponse(orq),
		  cr->cr_event,
		  status, phrase,
		  tags);

  if (cr->cr_waiting)
    /* Do not report call state change if waiting for restart */
    return 1;

  if (ss == NULL) {
    signal_call_state_change(nh, ss, status, phrase, nua_callstate_terminated);
    return 1;
  }

  ss->ss_reporting = 1;

  if (cr->cr_neutral) {
    signal_call_state_change(nh, ss, status, phrase, ss->ss_state);
    ss->ss_reporting = 0;
    return 1;
  }

  if (orq != cr->cr_orq && cr->cr_orq) {	/* Being restarted */
    next_state = nua_callstate_calling;
  }
  else if (status == 100) {
    next_state = nua_callstate_calling;
  }
  else if (status < 300 && cr->cr_graceful) {
    next_state = nua_callstate_terminating;
    if (200 <= status) {
      nua_invite_client_ack(cr, NULL);
    }
  }
  else if (status < 200) {
    next_state = nua_callstate_proceeding;

    if (sip && sip->sip_rseq && 
	!SIP_IS_ALLOWED(NH_PGET(nh, appl_method), sip_method_prack)) {
      sip_rack_t rack[1];

      sip_rack_init(rack);
      rack->ra_response    = sip->sip_rseq->rs_response;
      rack->ra_cseq        = sip->sip_cseq->cs_seq;
      rack->ra_method      = sip->sip_cseq->cs_method;
      rack->ra_method_name = sip->sip_cseq->cs_method_name;

      error = nua_client_tcreate(nh, nua_r_prack, &nua_prack_client_methods, 
				 SIPTAG_RACK(rack),
				 TAG_END());
      if (error < 0) {
	cr->cr_graceful = 1;
	next_state = nua_callstate_terminating;
      }
    }
  }
  else if (status < 300) {
    next_state = nua_callstate_completing;
  }
  else if (cr->cr_terminated) {
    next_state = nua_callstate_terminated;
  }
  else if (cr->cr_graceful && ss->ss_state >= nua_callstate_completing) {
    next_state = nua_callstate_terminating;
  }
  else {
    next_state = nua_callstate_init;
  }

  if (next_state == nua_callstate_calling) {
    if (sip && sip->sip_status && sip->sip_status->st_status == 100) {
      ss->ss_reporting = 0;
      return 1;
    }
  }

  if (next_state == nua_callstate_completing) {
    if (NH_PGET(nh, auto_ack) ||
	/* Auto-ACK response to re-INVITE unless auto_ack is set to 0 */
	(ss->ss_state == nua_callstate_ready &&
	 !NH_PISSET(nh, auto_ack))) {
      nua_client_request_t *cru;

      for (cru = ds->ds_cr; cru; cru = cru->cr_next) {
	if (cr != cru && cru->cr_offer_sent && !cru->cr_answer_recv)
	  break;
      }

      if (cru)
	/* A final response to UPDATE or PRACK with answer on its way? */;
      else if (nua_invite_client_ack(cr, NULL) > 0)
	next_state = nua_callstate_ready;
      else
	next_state = nua_callstate_terminating;
    }
  }

  if (next_state == nua_callstate_terminating) {
    /* Send BYE or CANCEL */
    /* XXX - Forking - send BYE to early dialog?? */
    if (ss->ss_state > nua_callstate_proceeding || status >= 200)
      error = nua_client_create(nh, nua_r_bye, &nua_bye_client_methods, NULL);
    else
      error = nua_client_create(nh, nua_r_cancel, 
				&nua_cancel_client_methods, tags);

    if (error) {
      next_state = nua_callstate_terminated;
      cr->cr_terminated = 1;
    }
    cr->cr_graceful = 0;
  }

  ss->ss_reporting = 0;

  signal_call_state_change(nh, ss, status, phrase, next_state);

  return 1;
}

/**@fn void nua_ack(nua_handle_t *nh, tag_type_t tag, tag_value_t value, ...);
 *
 * Acknowledge a succesful response to INVITE request.
 *
 * Acknowledge a successful response (200..299) to INVITE request with the
 * SIP ACK request message. This function is needed only if NUTAG_AUTOACK()
 * parameter has been cleared.
 *
 * @param nh              Pointer to operation handle
 * @param tag, value, ... List of tagged parameters
 *
 * @return 
 *    nothing
 *
 * @par Related Tags:
 *    Header tags defined in <sofia-sip/sip_tag.h>
 *
 * @par Events:
 *    #nua_i_media_error \n
 *    #nua_i_state  (#nua_i_active, #nua_i_terminated) 
 *
 * @sa NUTAG_AUTOACK(), @ref nua_call_model, #nua_i_state
 */

int nua_stack_ack(nua_t *nua, nua_handle_t *nh, nua_event_t e,
		  tagi_t const *tags)
{
  nua_dialog_usage_t *du = nua_dialog_usage_for_session(nh->nh_ds);
  nua_session_usage_t *ss = nua_dialog_usage_private(du);
  nua_client_request_t *cr = du ? du->du_cr : NULL;
  int error;

  if (!cr || cr->cr_orq == NULL || cr->cr_status < 200) {
    UA_EVENT2(nua_i_error, 900, "No response to ACK");
    return 1;
  }

  if (tags) {
    nua_stack_set_params(nua, nh, nua_i_error, tags);
    if (nh->nh_soa)
      soa_set_params(nh->nh_soa, TAG_NEXT(tags));
  }

  error = nua_invite_client_ack(cr, tags);

  if (error < 0) {
    if (ss->ss_reason == NULL)
      ss->ss_reason = "SIP;cause=500;text=\"Internal Error\"";