nua_stack.c

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

  size_t len, xtra, ee_len, l_len = 0, l_xtra = 0;
  ta_list ta;
  int retval = -1;

  if (nua == NULL)
    return -1;

  if (nua->nua_shutdown_started && event != nua_r_shutdown)
    return -1;

  ta_start(ta, tag, value);

  ee_len = offsetof(nua_ee_data_t, ee_data[0].e_tags);
  len = tl_len(ta_args(ta));
  xtra = tl_xtra(ta_args(ta), len);

  if (su_msg_new(sumsg, ee_len + len + l_len + xtra + l_xtra) == 0) {
    nua_ee_data_t *ee = su_msg_data(sumsg);
    nua_event_data_t *e = ee->ee_data;
    tagi_t *t = e->e_tags;
    void *b = (char *)t + len + l_len;

    tagi_t *tend = (tagi_t *)b;
    char *bend = (char *)b + xtra + l_xtra;

    t = tl_dup(t, ta_args(ta), &b);

    assert(tend == t); (void)tend; assert(b == bend); (void)bend;

    e->e_always = event == nua_r_destroy || event == nua_r_shutdown;
    e->e_event = event;
    e->e_nh = nh ? nua_handle_ref(nh) : NULL;
    e->e_status = status;
    e->e_phrase = phrase;

    su_msg_deinitializer(sumsg, nua_event_deinit);
      
    retval = su_msg_send_to(sumsg, nua->nua_server, nua_stack_signal);

    if (retval == 0){
      SU_DEBUG_7(("nua(%p): %s signal %s\n", (void *)nh,
		  "sent", nua_event_name(event) + 4));
    }
    else {
      SU_DEBUG_0(("nua(%p): %s signal %s\n", (void *)nh,
		  "FAILED TO SEND", nua_event_name(event) + 4));

    }
  }

  ta_end(ta);

  return retval;
}

/* ----------------------------------------------------------------------
 * Receiving events from client
 */
static
void nua_stack_signal(nua_t *nua, su_msg_r msg, nua_ee_data_t *ee)
{
  nua_event_data_t *e = ee->ee_data;
  nua_handle_t *nh = e->e_nh;
  tagi_t *tags = e->e_tags;
  nua_event_t event;
  int error = 0;

  if (nh) {
    if (!nh->nh_prev)
      nh_append(nua, nh);
    if (!nh->nh_ref_by_stack) {
      /* Mark handle as used by stack */
      nh->nh_ref_by_stack = 1;
      nua_handle_ref(nh);
    }
  }

  if (nua_log->log_level >= 5) {
    char const *name = nua_event_name(e->e_event);

    if (e->e_status == 0)
      SU_DEBUG_5(("nua(%p): %s signal %s\n", (void *)nh, "recv", name + 4));
    else
      SU_DEBUG_5(("nua(%p): recv signal %s %u %s\n",
		  (void *)nh, name + 4,
		  e->e_status, e->e_phrase ? e->e_phrase : ""));
  }

  su_msg_save(nua->nua_signal, msg);

  event = e->e_event;

  if (nua->nua_shutdown && !e->e_always) {
    /* Shutting down */
    nua_stack_event(nua, nh, NULL, event,
		    901, "Stack is going down",
		    NULL);
  }
  else switch (event) {
  case nua_r_get_params:
    nua_stack_get_params(nua, nh ? nh : nua->nua_dhandle, event, tags);
    break;
  case nua_r_set_params:
    nua_stack_set_params(nua, nh ? nh : nua->nua_dhandle, event, tags);
    break;
  case nua_r_shutdown:
    nua_stack_shutdown(nua);
    break;
  case nua_r_register:
  case nua_r_unregister:
    nua_stack_register(nua, nh, event, tags);
    break;
  case nua_r_invite:
    error = nua_stack_invite(nua, nh, event, tags);
    break;
  case nua_r_cancel:
    error = nua_stack_cancel(nua, nh, event, tags);
    break;
  case nua_r_bye:
    error = nua_stack_bye(nua, nh, event, tags);
    break;
  case nua_r_options:
    error = nua_stack_options(nua, nh, event, tags);
    break;
  case nua_r_refer:
    error = nua_stack_refer(nua, nh, event, tags);
    break;
  case nua_r_publish:
  case nua_r_unpublish:
    error = nua_stack_publish(nua, nh, event, tags);
    break;
  case nua_r_info:
    error = nua_stack_info(nua, nh, event, tags);
    break;
  case nua_r_prack:
    error = nua_stack_prack(nua, nh, event, tags);
    break;
  case nua_r_update:
    error = nua_stack_update(nua, nh, event, tags);
    break;
  case nua_r_message:
    error = nua_stack_message(nua, nh, event, tags);
    break;
  case nua_r_subscribe:
  case nua_r_unsubscribe:
    error = nua_stack_subscribe(nua, nh, event, tags);
    break;
  case nua_r_notify:
    error = nua_stack_notify(nua, nh, event, tags);
    break;
  case nua_r_notifier:
    nua_stack_notifier(nua, nh, event, tags);
    break;
  case nua_r_terminate:
    nua_stack_terminate(nua, nh, event, tags);
    break;
  case nua_r_method:
    error = nua_stack_method(nua, nh, event, tags);
    break;
  case nua_r_authenticate:
    nua_stack_authenticate(nua, nh, event, tags);
    break;
  case nua_r_authorize:
    nua_stack_authorize(nua, nh, event, tags);
    break;
  case nua_r_ack:
    error = nua_stack_ack(nua, nh, event, tags);
    break;
  case nua_r_respond:
    nua_stack_respond(nua, nh, e->e_status, e->e_phrase, tags);
    break;
  case nua_r_destroy: 
    nua_stack_destroy_handle(nua, nh, tags);
    su_msg_destroy(nua->nua_signal);
    return;
  default:
    break;
  }

  if (error < 0) {
    nua_stack_event(nh->nh_nua, nh, NULL, event,
		    NUA_ERROR_AT(__FILE__, __LINE__), NULL);
  }

  su_msg_destroy(nua->nua_signal);
}

/* ====================================================================== */
/* Signal and event handling */

/** Get event data.
 *
 * @sa #nua_event_e, nua_event_save(), nua_saved_event_request(), nua_destroy_event().
 */
nua_event_data_t const *nua_event_data(nua_saved_event_t const saved[1])
{
  return saved && saved[0] ? su_msg_data(saved)->ee_data : NULL;
}

/** Destroy saved event.
 *
 * @sa #nua_event_e, nua_event_save(), nua_event_data(), nua_saved_event_request().
 */
void nua_destroy_event(nua_saved_event_t saved[1])
{
  if (saved) su_msg_destroy(saved);
}

/** @internal Move signal. */
void nua_move_signal(nua_saved_signal_t a[1], nua_saved_signal_t b[1])
{
  su_msg_save(a, b);
}

void nua_destroy_signal(nua_saved_signal_t saved[1])
{
  if (saved) su_msg_destroy(saved);
}

nua_signal_data_t const *nua_signal_data(nua_saved_signal_t const saved[1])
{
  return nua_event_data(saved);
}

/* ====================================================================== */

static int nh_call_pending(nua_handle_t *nh, sip_time_t time);

/**@internal
 * Timer routine.
 *
 * Go through all active handles and execute pending tasks
 */
void nua_stack_timer(nua_t *nua, su_timer_t *t, su_timer_arg_t *a)
{
  nua_handle_t *nh, *nh_next;
  sip_time_t now = sip_now();
  su_root_t *root = su_timer_root(t);

  su_timer_set(t, nua_stack_timer, a);

  if (nua->nua_shutdown) {
    nua_stack_shutdown(nua);
    return;
  }

  for (nh = nua->nua_handles; nh; nh = nh_next) {
    nh_next = nh->nh_next;
    nh_call_pending(nh, now);
    su_root_yield(root);	/* Handle received packets */
  }
}


static
int nh_call_pending(nua_handle_t *nh, sip_time_t now)
{
  nua_dialog_state_t *ds = nh->nh_ds;
  nua_dialog_usage_t *du;
  sip_time_t next = now + NUA_STACK_TIMER_INTERVAL / 1000;

  for (du = ds->ds_usage; du; du = du->du_next) {
    if (now == 0)
      break;
    if (du->du_refresh && du->du_refresh < next)
      break;
  }

  if (du == NULL)
    return 0;

  nua_handle_ref(nh);

  while (du) {
    nua_dialog_usage_t *du_next = du->du_next;

    nua_dialog_usage_refresh(nh, ds, du, now);

    if (du_next == NULL)
      break;

    for (du = nh->nh_ds->ds_usage; du; du = du->du_next)
      if (du == du_next)
	break;

    for (; du; du = du->du_next) {
      if (now == 0)
	break;
      if (du->du_refresh && du->du_refresh < next)
	break;
    }
  }

  nua_handle_unref(nh);

  return 1;
}



/* ====================================================================== */

/**Shutdown a @nua stack.
 *
 * When the @nua stack is shutdown, ongoing calls are released,
 * registrations unregistered, publications un-PUBLISHed and subscriptions
 * terminated. If the stack cannot terminate everything within 30 seconds,
 * it sends the #nua_r_shutdown event with status 500.
 *
 * @param nua         Pointer to @nua stack object
 *
 * @return
 *     nothing
 *
 * @par Related tags:
 *     none
 *
 * @par Events:
 *     #nua_r_shutdown
 *
 * @sa #nua_r_shutdown, nua_destroy(), nua_create(), nua_bye(),
 * nua_unregister(), nua_unpublish(), nua_unsubscribe(), nua_notify(),
 * nua_handle_destroy(), nua_handle_unref()
 */

/** @NUA_EVENT nua_r_shutdown
 *
 * Answer to nua_shutdown().
 *
 * Status codes
 * - 100 shutdown started
 * - 101 shutdown in progress (sent when shutdown has been progressed)
 * - 200 shutdown was successful
 * - 500 shutdown timeout after 30 sec
 *
 * @param status shutdown status code
 * @param nh     NULL
 * @param hmagic NULL
 * @param sip    NULL
 * @param tags   empty
 *
 * @sa nua_shutdown(), nua_destroy()
 *
 * @END_NUA_EVENT
 */

/** @internal Shut down stack. */
void nua_stack_shutdown(nua_t *nua)
{
  nua_handle_t *nh, *nh_next;
  int busy = 0;
  sip_time_t now = sip_now();
  int status;
  char const *phrase;

  enter;

  if (!nua->nua_shutdown)
    nua->nua_shutdown = now;

  for (nh = nua->nua_handles; nh; nh = nh_next) {
    nua_dialog_state_t *ds = nh->nh_ds;

    nh_next = nh->nh_next;

    busy += nua_dialog_repeat_shutdown(nh, ds);

    if (nh->nh_soa) {
      soa_destroy(nh->nh_soa), nh->nh_soa = NULL;
    }

    if (nua_client_request_pending(ds->ds_cr))
      busy++;

    if (nh_notifier_shutdown(nh, NULL, NEATAG_REASON("noresource"), TAG_END()))
      busy++;
  }

  if (!busy)
    SET_STATUS(200, "Shutdown successful");
  else if (now == nua->nua_shutdown)
    SET_STATUS(100, "Shutdown started");
  else if (now - nua->nua_shutdown < 30)
    SET_STATUS(101, "Shutdown in progress");
  else
    SET_STATUS(500, "Shutdown timeout");

  if (status >= 200) {
    for (nh = nua->nua_handles; nh; nh = nh_next) {
      nh_next = nh->nh_next;
      while (nh->nh_ds && nh->nh_ds->ds_usage) {
	nua_dialog_usage_remove(nh, nh->nh_ds, nh->nh_ds->ds_usage, NULL, NULL);
      }
    }
    su_timer_destroy(nua->nua_timer), nua->nua_timer = NULL;
    nta_agent_destroy(nua->nua_nta), nua->nua_nta = NULL;
  }

  nua_stack_event(nua, NULL, NULL, nua_r_shutdown, status, phrase, NULL);
}

/* ---------------------------------------------------------------------- */

/** @internal Create a handle */
nua_handle_t *nh_create(nua_t *nua, tag_type_t tag, tag_value_t value, ...)
{
  ta_list ta;
  nua_handle_t *nh;

  enter;

  ta_start(ta, tag, value);
  nh = nh_create_handle(nua, NULL, ta_args(ta));
  ta_end(ta);

  if (nh) {
    nh->nh_ref_by_stack = 1;
    nh_append(nua, nh);
  }

  return nh;
}

/** @internal Append a handle to the list of handles */
void nh_append(nua_t *nua, nua_handle_t *nh)
{
  nh->nh_next = NULL;
  nh->nh_prev = nua->nua_handles_tail;
  *nua->nua_handles_tail = nh;
  nua->nua_handles_tail = &nh->nh_next;
}

nua_handle_t *nh_validate(nua_t *nua, nua_handle_t *maybe)
{
  nua_handle_t *nh;

  if (maybe)
    for (nh = nua->nua_handles; nh; nh = nh->nh_next)
      if (nh == maybe)
	return nh;

  return NULL;
}

void nua_stack_destroy_handle(nua_t *nua, nua_handle_t *nh, tagi_t const *tags)
{
  if (nh->nh_notifier)
    nua_stack_terminate(nua, nh, 0, NULL);

  nua_dialog_shutdown(nh, nh->nh_ds);

  if (nh->nh_ref_by_user) {
    nh->nh_ref_by_user = 0;
    nua_handle_unref(nh);
  }

  nh_destroy(nua, nh);
}

#define nh_is_inserted(nh) ((nh)->nh_prev != NULL)

/** @internal Remove a handle from list of handles */
static
void nh_remove(nua_t *nua, nua_handle_t *nh)
{
  assert(nh_is_inserted(nh)); assert(*nh->nh_prev == nh);

  if (nh->nh_next)
    nh->nh_next->nh_prev = nh->nh_prev;
  else
    nua->nua_handles_tail = nh->nh_prev;

  *nh->nh_prev = nh->nh_next;

  nh->nh_prev = NULL;
  nh->nh_next = NULL;
}