soa.c

this is simple sip stack.

/** Get local SDP.
 *
 * The local SDP is usually result of SDP negotiation.
 */
int soa_get_local_sdp(soa_session_t const *ss,
		      sdp_session_t const **return_sdp,
		      char const **return_sdp_str,
		      int *return_len)
{
  sdp_session_t const *sdp;
  char const *sdp_str;

  SU_DEBUG_9(("soa_get_local_sdp(%s::%p, [%p], [%p], [%p]) called\n",
	      ss ? ss->ss_actions->soa_name : "", ss,
	      return_sdp, return_sdp_str, return_len));

  if (ss == NULL)
    return (void)su_seterrno(EFAULT), -1;

  sdp = ss->ss_local->ssd_sdp;
  sdp_str = ss->ss_local->ssd_str;

  if (sdp == NULL)
    return 0;
  if (return_sdp)
    *return_sdp = sdp;
  if (return_sdp_str)
    *return_sdp_str = sdp_str;
  if (return_len)
    *return_len = strlen(sdp_str);

  return 1;
}

/** Initialize offer/answer state machine */
int soa_init_offer_answer(soa_session_t *ss)
{
  int complete;

  SU_DEBUG_9(("soa_init_offer_answer(%s::%p) called\n",
	      ss ? ss->ss_actions->soa_name : "", ss));

  if (!ss)
    return 0;

  complete = ss->ss_complete;

  ss->ss_complete = 0;
  ss->ss_offer_sent = 0;
  ss->ss_offer_recv = 0;
  ss->ss_answer_sent = 0;
  ss->ss_answer_recv = 0;

  ss->ss_unprocessed_remote = 0;

  return complete;
}

char **soa_media_features(soa_session_t *ss, int live, su_home_t *home)
{
  SU_DEBUG_9(("soa_media_features(%s::%p, %u, %p) called\n",
	      ss ? ss->ss_actions->soa_name : "", ss, live, home));

  if (ss)
    return ss->ss_actions->soa_media_features(ss, live, home);
  else
    return (void)su_seterrno(EFAULT), NULL;
}

char **soa_base_media_features(soa_session_t *ss, int live, su_home_t *home)
{
  return su_zalloc(home, 8 * sizeof (char **));
}

char const * const * soa_sip_require(soa_session_t const *ss)
{
  SU_DEBUG_9(("soa_sip_require(%s::%p) called\n",
	      ss ? ss->ss_actions->soa_name : "", ss));

  if (ss)
    return ss->ss_actions->soa_sip_require(ss);
  else
    return (void)su_seterrno(EFAULT), NULL;
}

char const * const * soa_base_sip_require(soa_session_t const *ss)
{
  static char const *null = NULL;
  return &null;
}

char const * const * soa_sip_supported(soa_session_t const *ss)
{
  SU_DEBUG_9(("soa_sip_supported(%s::%p) called\n",
	      ss ? ss->ss_actions->soa_name : "", ss));

  if (ss)
    return ss->ss_actions->soa_sip_supported(ss);
  else
    return (void)su_seterrno(EFAULT), NULL;
}

char const * const * soa_base_sip_supported(soa_session_t const *ss)
{
  static char const *null = NULL;
  return &null;
}

int soa_remote_sip_features(soa_session_t *ss,
			    char const * const * supported,
			    char const * const * require)
{
  SU_DEBUG_9(("soa_remote_sip_features(%s::%p, %p, %p) called\n",
	      ss ? ss->ss_actions->soa_name : "", ss, supported, require));

  if (ss)
    return ss->ss_actions->soa_remote_sip_features(ss, supported, require);
  else
    return (void)su_seterrno(EFAULT), -1;
}

int soa_base_remote_sip_features(soa_session_t *ss,
				    char const * const * supported,
				    char const * const * require)
{
  return 0;
}


/** Run Offer step.
 *
 * @param ss pointer to session object
 * @param always always send offer (even if offer/answer has been completed)
 * @param completed pointer to callback function which is invoked when
 *                  operation is completed
 *
 * @retval 1 when operation is successful
 * @retval 0 when operation is not needed
 * @retval -1 upon an error
 *
 * @ERRORS
 */
int soa_generate_offer(soa_session_t *ss,
		       int always,
		       soa_callback_f *completed)
{
  SU_DEBUG_9(("soa_generate_offer(%s::%p, %u, %p) called\n",
	      ss ? ss->ss_actions->soa_name : "", ss, always, completed));

  /** @ERROR EFAULT Bad address. */
  if (ss == NULL)
    return su_seterrno(EFAULT), -1;

  /** @ERROR An operation is already in progress */
  if (ss->ss_in_progress)
    return su_seterrno(EALREADY), -1;

  /** @ERROR EPROTO We have received offer, now we should send answer */
  if (ss->ss_offer_recv && !ss->ss_answer_sent)
    return su_seterrno(EPROTO), -1;

  /** @ERROR EPROTO We have received SDP, but it has not been processed */
  if (soa_has_received_sdp(ss))
    return su_seterrno(EPROTO), -1;

  /** @ERROR EPROTO We have sent an offer, but have received no answer */
  if (ss->ss_offer_sent && !ss->ss_answer_recv)
    return su_seterrno(EPROTO), -1;

  /** @ERROR EPROTO We have received offer. */
  if (ss->ss_unprocessed_remote)
    return su_seterrno(EPROTO), -1;

  /* We should avoid actual operation unless always is true */
  (void)always;  /* We always regenerate offer */

  return ss->ss_actions->soa_generate_offer(ss, completed);
}

int soa_base_generate_offer(soa_session_t *ss,
			    soa_callback_f *completed)
{
  sdp_session_t const *sdp = ss->ss_local->ssd_sdp;

  (void)completed;

  if (!sdp)
    return -1;

  soa_set_activity(ss, sdp->sdp_media, 0);

  ss->ss_offer_sent = 1;
  ss->ss_answer_recv = 0;

  return 0;
}

/* Generate answer */
int soa_generate_answer(soa_session_t *ss,
			soa_callback_f *completed)
{
  SU_DEBUG_9(("soa_generate_answer(%s::%p, %p) called\n",
	      ss ? ss->ss_actions->soa_name : "", ss, completed));

  /** @ERROR EFAULT Bad address as @a ss. */
  if (ss == NULL)
    return su_seterrno(EFAULT), -1;

  /** @ERROR An operation is already in progress. */
  if (ss->ss_in_progress)
    return su_seterrno(EALREADY), -1;

  /** @ERROR EPROTO We have sent an offer, but have received no answer. */
  if (ss->ss_offer_sent && !ss->ss_answer_recv)
    return su_seterrno(EPROTO), -1;

  /** @ERROR EPROTO We have not received offer. */
  if (!ss->ss_unprocessed_remote)
    return su_seterrno(EPROTO), -1;

  return ss->ss_actions->soa_generate_answer(ss, completed);
}

int soa_base_generate_answer(soa_session_t *ss,
			     soa_callback_f *completed)
{
  sdp_session_t const *l_sdp = ss->ss_local->ssd_sdp;
  sdp_session_t const *r_sdp = ss->ss_remote->ssd_sdp;
  sdp_session_t *rsession;

  (void)completed;

  if (!l_sdp || !r_sdp)
    return -1;
  rsession = sdp_session_dup(ss->ss_home, r_sdp);
  if (!rsession)
    return -1;

  if (ss->ss_rsession)
    su_free(ss->ss_home, ss->ss_rsession);
  ss->ss_rsession = rsession;

  soa_set_activity(ss, l_sdp->sdp_media, 0);
  soa_set_activity(ss, r_sdp->sdp_media, 1);

  ss->ss_offer_recv = 1;
  ss->ss_answer_sent = 1;
  ss->ss_complete = 1;
  ss->ss_unprocessed_remote = 0;

  return 0;
}

/** Complete offer-answer after receiving answer */
int soa_process_answer(soa_session_t *ss,
		       soa_callback_f *completed)
{
  SU_DEBUG_9(("soa_process_answer(%s::%p, %p) called\n",
	      ss ? ss->ss_actions->soa_name : "", ss, completed));

  /** @ERROR EFAULT Bad address as @a ss. */
  if (ss == NULL)
    return su_seterrno(EFAULT), -1;

  /** @ERROR An operation is already in progress. */
  if (ss->ss_in_progress)
    return su_seterrno(EALREADY), -1;

  /** @ERROR EPROTO We have not sent an offer 
      or already have received answer. */
  if (!ss->ss_offer_sent || ss->ss_answer_recv)
    return su_seterrno(EPROTO), -1;

  /** @ERROR EPROTO We have not received answer. */
  if (!ss->ss_unprocessed_remote)
    return su_seterrno(EPROTO), -1;

  return ss->ss_actions->soa_process_answer(ss, completed);
}

/** 
 * Processes answer from remote end.
 */
int soa_base_process_answer(soa_session_t *ss,
			    soa_callback_f *completed)
{
  sdp_session_t const *l_sdp = ss->ss_local->ssd_sdp;
  sdp_session_t const *r_sdp = ss->ss_remote->ssd_sdp;
  sdp_session_t *rsession;

  (void)completed;

  if (!l_sdp || !r_sdp)
    return -1;
  rsession = sdp_session_dup(ss->ss_home, r_sdp);
  if (!rsession)
    return -1;

  if (ss->ss_rsession)
    su_free(ss->ss_home, ss->ss_rsession);
  ss->ss_rsession = rsession;

  soa_set_activity(ss, l_sdp->sdp_media, 0);
  soa_set_activity(ss, r_sdp->sdp_media, 1);

  ss->ss_answer_recv = 1;
  ss->ss_complete = 1;
  ss->ss_unprocessed_remote = 0;

  return 0;
}

/** Process rejection of offer */
int soa_process_reject(soa_session_t *ss,
		       soa_callback_f *completed)
{
  SU_DEBUG_9(("soa_process_reject(%s::%p, %p) called\n",
	      ss ? ss->ss_actions->soa_name : "", ss, completed));

  /** @ERROR EFAULT Bad address as @a ss. */
  if (ss == NULL)
    return su_seterrno(EFAULT), -1;

  /** @ERROR An operation is already in progress. */
  if (ss->ss_in_progress)
    return su_seterrno(EALREADY), -1;

  /** @ERROR EPROTO We have not sent an offer 
      or already have received answer. */
  if (!ss->ss_offer_sent || ss->ss_answer_recv)
    return su_seterrno(EPROTO), -1;

  return ss->ss_actions->soa_process_reject(ss, completed);
}

/** 
 * Process reject from remote end.
 */
int soa_base_process_reject(soa_session_t *ss,
			    soa_callback_f *completed)
{
  sdp_session_t const *l_sdp = ss->ss_local->ssd_sdp;

  (void)completed;

  if (!l_sdp)
    return -1;

  soa_set_activity(ss, l_sdp->sdp_media, 0);

  ss->ss_offer_sent = 0;

  return 0;
}

/** Activate session */
int soa_activate(soa_session_t *ss, char const *option)
{
  SU_DEBUG_9(("soa_activate(%s::%p, %s%s%s) called\n",
	      ss ? ss->ss_actions->soa_name : "", ss, NICE(option)));

  /** @ERROR EFAULT Bad address as @a ss. */
  if (ss == NULL)
    return -1;

  ss->ss_active = 1;

  return ss->ss_actions->soa_activate_session(ss, option);
}

int soa_base_activate(soa_session_t *ss, char const *option)
{
  (void)ss;
  (void)option;
  return 0;
}

/** Deactivate session */
int soa_deactivate(soa_session_t *ss, char const *option)
{
  SU_DEBUG_9(("soa_deactivate(%s::%p, %s%s%s) called\n",
	      ss ? ss->ss_actions->soa_name : "", ss, NICE(option)));

  /** @ERROR EFAULT Bad address as @a ss. */
  if (ss == NULL)
    return -1;

  ss->ss_active = 0;

  return ss->ss_actions->soa_deactivate_session(ss, option);
}

int soa_base_deactivate(soa_session_t *ss, char const *option)
{
  (void)ss;
  (void)option;
  return 0;
}

/** Terminate session */
void soa_terminate(soa_session_t *ss, char const *option)
{
  SU_DEBUG_9(("soa_terminate(%s::%p) called\n",
	      ss ? ss->ss_actions->soa_name : "", ss));

  /** @ERROR EFAULT Bad address as @a ss. */
  if (ss == NULL)
    return;

  ss->ss_active = 0;
  ss->ss_terminated++;

  ss->ss_actions->soa_terminate_session(ss, option);
}

void soa_base_terminate(soa_session_t *ss, char const *option)
{
  (void)option;

  soa_init_offer_answer(ss);
  ss->ss_oa_rounds = 0;

  soa_description_free(ss, ss->ss_remote);
  soa_set_activity(ss, NULL, 0);
  soa_set_activity(ss, NULL, 1);
}

int soa_has_received_sdp(soa_session_t const *ss)
{
  return ss && ss->ss_unprocessed_remote;
}

int soa_is_complete(soa_session_t const *ss)
{
  return ss && ss->ss_complete;
}

int soa_is_audio_active(soa_session_t const *ss)
{
  return ss ? ss->ss_local_activity->ma_audio : SOA_ACTIVE_DISABLED;
}

int soa_is_video_active(soa_session_t const *ss)
{
  return ss ? ss->ss_local_activity->ma_video : SOA_ACTIVE_DISABLED;
}

int soa_is_image_active(soa_session_t const *ss)
{
  return ss ? ss->ss_local_activity->ma_image : SOA_ACTIVE_DISABLED;
}

int soa_is_chat_active(soa_session_t const *ss)
{
  return ss ? ss->ss_local_activity->ma_chat : SOA_ACTIVE_DISABLED;
}

int soa_is_remote_audio_active(soa_session_t const *ss)
{
  return ss ? ss->ss_remote_activity->ma_audio : SOA_ACTIVE_DISABLED;
}

int soa_is_remote_video_active(soa_session_t const *ss)
{
  return ss ? ss->ss_remote_activity->ma_video : SOA_ACTIVE_DISABLED;
}

int soa_is_remote_image_active(soa_session_t const *ss)
{
  return ss ? ss->ss_remote_activity->ma_image : SOA_ACTIVE_DISABLED;
}

int soa_is_remote_chat_active(soa_session_t const *ss)
{
  return ss ? ss->ss_remote_activity->ma_chat : SOA_ACTIVE_DISABLED;