osip_dialog.c

mediastreamer2是开源的网络传输媒体流的库

     From: remote_uri;remote_tag
   */

  if (dlg->local_tag == NULL)
    /* NOT POSSIBLE BECAUSE I MANAGE REMOTE_TAG AND I ALWAYS ADD IT! */
    return OSIP_SYNTAXERROR;

  i = osip_from_get_tag (request->from, &tag_param_remote);
  if (i != 0 && dlg->remote_tag != NULL)        /* no tag in request but tag in dialog */
    return OSIP_SYNTAXERROR;                  /* impossible... */
  if (i != 0 && dlg->remote_tag == NULL)        /* no tag in request AND no tag in dialog */
    {
      if (0 ==
          osip_from_compare ((osip_from_t *) dlg->remote_uri,
                             (osip_from_t *) request->from)
          && 0 == osip_from_compare (dlg->local_uri, request->to))
        return OSIP_SUCCESS;
      return OSIP_UNDEFINED_ERROR;
    }

  if (dlg->remote_tag == NULL)  /* tag in response BUT no tag in dialog */
    {
      OSIP_TRACE (osip_trace
                  (__FILE__, __LINE__, OSIP_WARNING, NULL,
                   "Remote UA is not compliant: missing a tag in To feilds!\n"));
      if (0 ==
          osip_from_compare ((osip_from_t *) dlg->remote_uri,
                             (osip_from_t *) request->from)
          && 0 == osip_from_compare (dlg->local_uri, request->to))
        return OSIP_SUCCESS;
      return OSIP_UNDEFINED_ERROR;
    }
  /* we don't have to compare
     remote_uri with from
     && local_uri with to.    ----> we have both tag recognized, it's enough..
   */
  if (0 == strcmp (tag_param_remote->gvalue, dlg->remote_tag))
    return OSIP_SUCCESS;

  return OSIP_UNDEFINED_ERROR;
}

static int
__osip_dialog_init (osip_dialog_t ** dialog,
		    osip_message_t * invite,
		    osip_message_t * response,
		    osip_from_t *local, osip_to_t *remote,
		    osip_message_t *remote_msg)
{
  int i;
  int pos;
  osip_generic_param_t *tag;

  *dialog = NULL;
  if (response==NULL)
    return OSIP_BADPARAMETER;
  if (response->cseq==NULL || local==NULL || remote==NULL)
    return OSIP_SYNTAXERROR;

  (*dialog) = (osip_dialog_t *) osip_malloc (sizeof (osip_dialog_t));
  if (*dialog == NULL)
    return OSIP_NOMEM;

  memset (*dialog, 0, sizeof (osip_dialog_t));
  (*dialog)->your_instance = NULL;

  if (MSG_IS_STATUS_2XX (response))
    (*dialog)->state = DIALOG_CONFIRMED;
  else                          /* 1XX */
    (*dialog)->state = DIALOG_EARLY;

  i = osip_call_id_to_str (response->call_id, &((*dialog)->call_id));
  if (i != 0)
  {
	  OSIP_TRACE (osip_trace
				  (__FILE__, __LINE__, OSIP_ERROR, NULL,
				   "Could not establish dialog!\n"));
	  osip_dialog_free(*dialog);
	  *dialog = NULL;
	  return i;
  }

  i = osip_to_get_tag (local, &tag);
  if (i != 0)
  {
	  OSIP_TRACE (osip_trace
				  (__FILE__, __LINE__, OSIP_ERROR, NULL,
				   "Could not establish dialog!\n"));
	  osip_dialog_free(*dialog);
	  *dialog = NULL;
	  return i;
  }

  (*dialog)->local_tag = osip_strdup (tag->gvalue);

  i = osip_from_get_tag (remote, &tag);
  if (i == 0)
    (*dialog)->remote_tag = osip_strdup (tag->gvalue);

  osip_list_init (&(*dialog)->route_set);

  pos = 0;
  while (!osip_list_eol (&response->record_routes, pos))
    {
      osip_record_route_t *rr;
      osip_record_route_t *rr2;

      rr = (osip_record_route_t *) osip_list_get (&response->record_routes, pos);
      i = osip_record_route_clone (rr, &rr2);
      if (i != 0)
	  {
		  OSIP_TRACE (osip_trace
					  (__FILE__, __LINE__, OSIP_ERROR, NULL,
					   "Could not establish dialog!\n"));
		  osip_dialog_free(*dialog);
		  *dialog = NULL;
		  return i;
	  }
      if (invite==NULL)
	osip_list_add (&(*dialog)->route_set, rr2, 0);
      else
	osip_list_add (&(*dialog)->route_set, rr2, -1);

      pos++;
    }

  /* local_cseq is set to response->cseq->number for better
     handling of bad UA */
  (*dialog)->local_cseq = osip_atoi (response->cseq->number);

  i = osip_from_clone (remote, &((*dialog)->remote_uri));
  if (i != 0)
  {
	  OSIP_TRACE (osip_trace
				  (__FILE__, __LINE__, OSIP_ERROR, NULL,
				   "Could not establish dialog!\n"));
	  osip_dialog_free(*dialog);
	  *dialog = NULL;
	  return i;
  }

  i = osip_to_clone (local, &((*dialog)->local_uri));
  if (i != 0)
  {
	  OSIP_TRACE (osip_trace
				  (__FILE__, __LINE__, OSIP_ERROR, NULL,
				   "Could not establish dialog!\n"));
	  osip_dialog_free(*dialog);
	  *dialog = NULL;
	  return i;
  }

  {
    osip_contact_t *contact;

    if (!osip_list_eol (&remote_msg->contacts, 0))
      {
        contact = osip_list_get (&remote_msg->contacts, 0);
        i = osip_contact_clone (contact, &((*dialog)->remote_contact_uri));
        if (i != 0)
		{
		  OSIP_TRACE (osip_trace
					  (__FILE__, __LINE__, OSIP_ERROR, NULL,
					   "Could not establish dialog!\n"));
		  osip_dialog_free(*dialog);
		  *dialog = NULL;
		  return i;
		}
    } else
      {
        (*dialog)->remote_contact_uri = NULL;
        OSIP_TRACE (osip_trace
                    (__FILE__, __LINE__, OSIP_WARNING, NULL,
                     "Remote UA is not compliant: missing a contact in remote message!\n"));
      }
  }
  (*dialog)->secure = -1;       /* non secure */

  return OSIP_SUCCESS;
}

int
osip_dialog_init_as_uac (osip_dialog_t ** dialog, osip_message_t * response)
{
  int i;

  i = __osip_dialog_init (dialog,
			  NULL,
			  response,
			  response->from, response->to,
			  response);

  if (i!=0)
    {
      *dialog = NULL;
      return i;
    }

  (*dialog)->type = CALLER;
  (*dialog)->remote_cseq = -1;

  return OSIP_SUCCESS;
}

/* SIPIT13 */
int
osip_dialog_init_as_uac_with_remote_request (osip_dialog_t ** dialog,
                                             osip_message_t * next_request,
                                             int local_cseq)
{
  int i;

  *dialog = NULL;
  if (next_request->cseq==NULL)
    return OSIP_BADPARAMETER;

  i = __osip_dialog_init (dialog,
			  next_request,
			  next_request,
			  next_request->to, next_request->from,
			  next_request);

  if (i!=0)
    {
      *dialog = NULL;
      return i;
    }

  (*dialog)->type = CALLER;
  (*dialog)->state = DIALOG_CONFIRMED;

  (*dialog)->local_cseq = local_cseq;   /* -1 osip_atoi (xxx->cseq->number); */
  (*dialog)->remote_cseq = osip_atoi (next_request->cseq->number);

  return OSIP_SUCCESS;
}

int
osip_dialog_init_as_uas (osip_dialog_t ** dialog, osip_message_t * invite,
                         osip_message_t * response)
{
  int i;

  *dialog = NULL;
  if (response->cseq==NULL)
    return OSIP_SYNTAXERROR;

  i = __osip_dialog_init (dialog,
			  invite,
			  response,
			  response->to, response->from,
			  invite);

  if (i!=0)
    {
      *dialog = NULL;
      return i;
    }

  (*dialog)->type = CALLEE;
  (*dialog)->remote_cseq = osip_atoi (response->cseq->number);

  return OSIP_SUCCESS;
}

void
osip_dialog_free (osip_dialog_t * dialog)
{
  if (dialog == NULL)
    return;
  osip_contact_free (dialog->remote_contact_uri);
  osip_from_free (dialog->local_uri);
  osip_to_free (dialog->remote_uri);
  osip_list_special_free (&dialog->route_set,
                          (void *(*)(void *)) &osip_record_route_free);
  osip_free (dialog->remote_tag);
  osip_free (dialog->local_tag);
  osip_free (dialog->call_id);
  osip_free (dialog);
}