/*
 * Set default codec parameter.
 */
PJ_DEF(pj_status_t) pjmedia_codec_mgr_set_default_param( 
					    pjmedia_codec_mgr *mgr,
					    const pjmedia_codec_info *info,
					    const pjmedia_codec_param *param )
{
    unsigned i;
    pjmedia_codec_id codec_id;
    pj_pool_t *pool, *old_pool = NULL;
    struct pjmedia_codec_desc *codec_desc = NULL;
    pjmedia_codec_default_param *p;

    PJ_ASSERT_RETURN(mgr && info, PJ_EINVAL);

    if (!pjmedia_codec_info_to_id(info, (char*)&codec_id, sizeof(codec_id)))
	return PJ_EINVAL;

    pj_mutex_lock(mgr->mutex);

    /* Lookup codec desc */
    for (i=0; i < mgr->codec_cnt; ++i) {
	if (pj_ansi_stricmp(codec_id, mgr->codec_desc[i].id) == 0) {
	    codec_desc = &mgr->codec_desc[i];
	    break;
	}
    }

    /* Codec not found */
    if (!codec_desc) {
	pj_mutex_unlock(mgr->mutex);
	return PJMEDIA_CODEC_EUNSUP;
    }

    /* If codec param is previously set, reset the codec param but release
     * the codec param pool later after the new param is set (ticket #1171).
     */
    if (codec_desc->param) {
	pj_assert(codec_desc->param->pool);
        old_pool = codec_desc->param->pool;
	codec_desc->param = NULL;
    }

    /* When param is set to NULL, i.e: setting default codec param to library
     * default setting, just return PJ_SUCCESS.
     */
    if (NULL == param) {
	pj_mutex_unlock(mgr->mutex);
        if (old_pool)
	    pj_pool_release(old_pool);
	return PJ_SUCCESS;
    }

    /* Instantiate and initialize codec param */
    pool = pj_pool_create(mgr->pf, (char*)codec_id, 256, 256, NULL);
    codec_desc->param = PJ_POOL_ZALLOC_T(pool, pjmedia_codec_default_param);
    p = codec_desc->param;
    p->pool = pool;
    p->param = PJ_POOL_ZALLOC_T(pool, pjmedia_codec_param);

    /* Update codec param */
    pj_memcpy(p->param, param, sizeof(pjmedia_codec_param));
    for (i = 0; i < param->setting.dec_fmtp.cnt; ++i) {
	pj_strdup(pool, &p->param->setting.dec_fmtp.param[i].name, 
		  &param->setting.dec_fmtp.param[i].name);
	pj_strdup(pool, &p->param->setting.dec_fmtp.param[i].val, 
		  &param->setting.dec_fmtp.param[i].val);
    }
    for (i = 0; i < param->setting.enc_fmtp.cnt; ++i) {
	pj_strdup(pool, &p->param->setting.enc_fmtp.param[i].name, 
		  &param->setting.enc_fmtp.param[i].name);
	pj_strdup(pool, &p->param->setting.enc_fmtp.param[i].val, 
		  &param->setting.enc_fmtp.param[i].val);
    }

    pj_mutex_unlock(mgr->mutex);

    if (old_pool)
	pj_pool_release(old_pool);

    return PJ_SUCCESS;
}

/*
 * Create the AEC. 
 */
PJ_DEF(pj_status_t) speex_aec_create(pj_pool_t *pool,
				     unsigned clock_rate,
				     unsigned channel_count,
				     unsigned samples_per_frame,
				     unsigned tail_ms,
				     unsigned options,
				     void **p_echo )
{
    speex_ec *echo;
    int sampling_rate;

    *p_echo = NULL;

    echo = PJ_POOL_ZALLOC_T(pool, speex_ec);
    PJ_ASSERT_RETURN(echo != NULL, PJ_ENOMEM);

    echo->samples_per_frame = samples_per_frame;
    echo->options = options;

#if 0
    echo->state = speex_echo_state_init_mc(echo->samples_per_frame,
					   clock_rate * tail_ms / 1000,
					   channel_count, channel_count);
#else
    if (channel_count != 1) {
	PJ_LOG(2,("echo_speex.c", "Multichannel EC is not supported by this "
				  "echo canceller. It may not work."));
    }
    echo->state = speex_echo_state_init(echo->samples_per_frame,
    					clock_rate * tail_ms / 1000);
#endif
    if (echo->state == NULL) {
	return PJ_ENOMEM;
    }

    /* Set sampling rate */
    sampling_rate = clock_rate;
    speex_echo_ctl(echo->state, SPEEX_ECHO_SET_SAMPLING_RATE, 
		   &sampling_rate);

    echo->preprocess = speex_preprocess_state_init(echo->samples_per_frame,
						   clock_rate);
    if (echo->preprocess == NULL) {
	speex_echo_state_destroy(echo->state);
	return PJ_ENOMEM;
    }

    /* Disable all preprocessing, we only want echo cancellation */
#if 0
    disabled = 0;
    enabled = 1;
    speex_preprocess_ctl(echo->preprocess, SPEEX_PREPROCESS_SET_DENOISE, 
			 &enabled);
    speex_preprocess_ctl(echo->preprocess, SPEEX_PREPROCESS_SET_AGC, 
			 &disabled);
    speex_preprocess_ctl(echo->preprocess, SPEEX_PREPROCESS_SET_VAD, 
			 &disabled);
    speex_preprocess_ctl(echo->preprocess, SPEEX_PREPROCESS_SET_DEREVERB, 
			 &enabled);
#endif

    /* Control echo cancellation in the preprocessor */
   speex_preprocess_ctl(echo->preprocess, SPEEX_PREPROCESS_SET_ECHO_STATE, 
			echo->state);


    /* Create temporary frame for echo cancellation */
    echo->tmp_frame = (pj_int16_t*) pj_pool_zalloc(pool, 2*samples_per_frame);
    PJ_ASSERT_RETURN(echo->tmp_frame != NULL, PJ_ENOMEM);

    /* Done */
    *p_echo = echo;
    return PJ_SUCCESS;

}

/* API: create stream */
static pj_status_t vid4lin_factory_create_stream(pjmedia_vid_dev_factory *f,
				      pjmedia_vid_dev_param *param,
				      const pjmedia_vid_dev_cb *cb,
				      void *user_data,
				      pjmedia_vid_dev_stream **p_vid_strm)
{
    vid4lin_factory *cf = (vid4lin_factory*)f;
    pj_pool_t *pool;
    vid4lin_stream *stream;
    vid4lin_dev_info *vdi;
    const vid4lin_fmt_map *fmt_map;
    const pjmedia_video_format_info *fmt_info;
    pjmedia_video_format_detail *vfd;
    pj_status_t status = PJ_SUCCESS;


    PJ_ASSERT_RETURN(f && param && p_vid_strm, PJ_EINVAL);
    PJ_ASSERT_RETURN(param->fmt.type == PJMEDIA_TYPE_VIDEO &&
		     param->fmt.detail_type == PJMEDIA_FORMAT_DETAIL_VIDEO &&
                     param->dir == PJMEDIA_DIR_CAPTURE,
		     PJ_EINVAL);
    PJ_ASSERT_RETURN(param->cap_id >= 0 && param->cap_id < cf->dev_count,
		     PJMEDIA_EVID_INVDEV);

    fmt_info = pjmedia_get_video_format_info(NULL, param->fmt.id);
    if (!fmt_info || (fmt_map=get_v4l2_format_info(param->fmt.id))==NULL)
        return PJMEDIA_EVID_BADFORMAT;

    vdi = &cf->dev_info[param->cap_id];
    vfd = pjmedia_format_get_video_format_detail(&param->fmt, PJ_TRUE);

    /* Create and Initialize stream descriptor */
    pool = pj_pool_create(cf->pf, vdi->info.name, 512, 512, NULL);
    PJ_ASSERT_RETURN(pool != NULL, PJ_ENOMEM);

    stream = PJ_POOL_ZALLOC_T(pool, vid4lin_stream);
    pj_memcpy(&stream->param, param, sizeof(*param));
    stream->pool = pool;
    pj_memcpy(&stream->vid_cb, cb, sizeof(*cb));
    strncpy(stream->name, vdi->info.name, sizeof(stream->name));
    stream->name[sizeof(stream->name)-1] = '\0';
    stream->user_data = user_data;
    stream->fd = INVALID_FD;

    stream->fd = v4l2_open(vdi->dev_name, O_RDWR, 0);
    if (stream->fd < 0)
	goto on_error;

    status = vid4lin_stream_init_fmt(stream, param, fmt_map->v4l2_fmt_id);
    if (status != PJ_SUCCESS)
	goto on_error;

    if (vdi->v4l2_cap.capabilities & V4L2_CAP_STREAMING)
	status = vid4lin_stream_init_streaming(stream);

    if (status!=PJ_SUCCESS && vdi->v4l2_cap.capabilities & V4L2_CAP_STREAMING)
	status = vid4lin_stream_init_streaming_user(stream);

    if (status!=PJ_SUCCESS && vdi->v4l2_cap.capabilities & V4L2_CAP_READWRITE)
	status = vid4lin_stream_init_read_write(stream);

    if (status != PJ_SUCCESS) {
	PJ_LOG(1,(THIS_FILE, "Error: unable to initiate I/O on %s",
		  stream->name));
	goto on_error;
    }

    /* Done */
    stream->base.op = &stream_op;
    *p_vid_strm = &stream->base;

    return PJ_SUCCESS;

on_error:
    if (status == PJ_SUCCESS)
	status = PJ_RETURN_OS_ERROR(errno);

    vid4lin_stream_destroy(&stream->base);
    return status;
}

static pj_xml_attr *alloc_attr( pj_pool_t *pool )
{
    return PJ_POOL_ZALLOC_T(pool, pj_xml_attr);
}

static pj_status_t set_contact( pjsip_regc *regc,
			        int contact_cnt,
				const pj_str_t contact[] )
{
    const pj_str_t CONTACT = { "Contact", 7 };
    pjsip_contact_hdr *h;
    int i;
    
    /* Save existing contact list to removed_contact_hdr_list and
     * clear contact_hdr_list.
     */
    pj_list_merge_last(&regc->removed_contact_hdr_list, 
		       &regc->contact_hdr_list);

    /* Set the expiration of Contacts in to removed_contact_hdr_list 
     * zero.
     */
    h = regc->removed_contact_hdr_list.next;
    while (h != &regc->removed_contact_hdr_list) {
	h->expires = 0;
	h = h->next;
    }

    /* Process new contacts */
    for (i=0; i<contact_cnt; ++i) {
	pjsip_contact_hdr *hdr;
	pj_str_t tmp;

	pj_strdup_with_null(regc->pool, &tmp, &contact[i]);
	hdr = (pjsip_contact_hdr*)
              pjsip_parse_hdr(regc->pool, &CONTACT, tmp.ptr, tmp.slen, NULL);
	if (hdr == NULL) {
	    PJ_LOG(4,(THIS_FILE, "Invalid Contact: \"%.*s\"", 
		     (int)tmp.slen, tmp.ptr));
	    return PJSIP_EINVALIDURI;
	}

	/* Find the new contact in old contact list. If found, remove
	 * the old header from the old header list.
	 */
	h = regc->removed_contact_hdr_list.next;
	while (h != &regc->removed_contact_hdr_list) {
	    int rc;

	    rc = pjsip_uri_cmp(PJSIP_URI_IN_CONTACT_HDR, 
			       h->uri, hdr->uri);
	    if (rc == 0) {
		/* Match */
		pj_list_erase(h);
		break;
	    }

	    h = h->next;
	}

	/* If add_xuid_param option is enabled and Contact URI is sip/sips,
	 * add xuid parameter to assist matching the Contact URI in the 
	 * REGISTER response later.
	 */
	if (regc->add_xuid_param && (PJSIP_URI_SCHEME_IS_SIP(hdr->uri) ||
				     PJSIP_URI_SCHEME_IS_SIPS(hdr->uri))) 
	{
	    pjsip_param *xuid_param;
	    pjsip_sip_uri *sip_uri;

	    xuid_param = PJ_POOL_ZALLOC_T(regc->pool, pjsip_param);
	    xuid_param->name = XUID_PARAM_NAME;
	    pj_create_unique_string(regc->pool, &xuid_param->value);

	    sip_uri = (pjsip_sip_uri*) pjsip_uri_get_uri(hdr->uri);
	    pj_list_push_back(&sip_uri->other_param, xuid_param);
	}

	pj_list_push_back(&regc->contact_hdr_list, hdr);
    }

    return PJ_SUCCESS;
}

/*
 * Create new allocation.
 */
PJ_DEF(pj_status_t) pj_turn_allocation_create(pj_turn_transport *transport,
					      const pj_sockaddr_t *src_addr,
					      unsigned src_addr_len,
					      const pj_stun_rx_data *rdata,
					      pj_stun_session *srv_sess,
					      pj_turn_allocation **p_alloc)
{
    pj_turn_srv *srv = transport->listener->server;
    const pj_stun_msg *msg = rdata->msg;
    pj_pool_t *pool;
    alloc_request req;
    pj_turn_allocation *alloc;
    pj_stun_session_cb sess_cb;
    char str_tmp[80];
    pj_status_t status;

    /* Parse ALLOCATE request */
    status = parse_allocate_req(&req, srv_sess, rdata, src_addr, src_addr_len);
    if (status != PJ_SUCCESS)
	return status;

    pool = pj_pool_create(srv->core.pf, "alloc%p", 1000, 1000, NULL);

    /* Init allocation structure */
    alloc = PJ_POOL_ZALLOC_T(pool, pj_turn_allocation);
    alloc->pool = pool;
    alloc->obj_name = pool->obj_name;
    alloc->relay.tp.sock = PJ_INVALID_SOCKET;
    alloc->server = transport->listener->server;

    alloc->bandwidth = req.bandwidth;

    /* Set transport */
    alloc->transport = transport;
    pj_turn_transport_add_ref(transport, alloc);

    alloc->hkey.tp_type = transport->listener->tp_type;
    pj_memcpy(&alloc->hkey.clt_addr, src_addr, src_addr_len);

    status = pj_lock_create_recursive_mutex(pool, alloc->obj_name, 
					    &alloc->lock);
    if (status != PJ_SUCCESS) {
	goto on_error;
    }

    /* Create peer hash table */
    alloc->peer_table = pj_hash_create(pool, PEER_TABLE_SIZE);

    /* Create channel hash table */
    alloc->ch_table = pj_hash_create(pool, PEER_TABLE_SIZE);

    /* Print info */
    pj_ansi_strcpy(alloc->info, 
		   pj_turn_tp_type_name(transport->listener->tp_type));
    alloc->info[3] = ':';
    pj_sockaddr_print(src_addr, alloc->info+4, sizeof(alloc->info)-4, 3);

    /* Create STUN session to handle STUN communication with client */
    pj_bzero(&sess_cb, sizeof(sess_cb));
    sess_cb.on_send_msg = &stun_on_send_msg;
    sess_cb.on_rx_request = &stun_on_rx_request;
    sess_cb.on_rx_indication = &stun_on_rx_indication;
    status = pj_stun_session_create(&srv->core.stun_cfg, alloc->obj_name,
				    &sess_cb, PJ_FALSE, &alloc->sess);
    if (status != PJ_SUCCESS) {
	goto on_error;
    }

    /* Attach to STUN session */
    pj_stun_session_set_user_data(alloc->sess, alloc);

    /* Init authentication credential */
    status = init_cred(alloc, msg);
    if (status != PJ_SUCCESS) {
	goto on_error;
    }

    /* Attach authentication credential to STUN session */
    pj_stun_session_set_credential(alloc->sess, PJ_STUN_AUTH_LONG_TERM,
				   &alloc->cred);

    /* Create the relay resource */
    status = create_relay(srv, alloc, msg, &req, &alloc->relay);
    if (status != PJ_SUCCESS) {
	goto on_error;
    }

    /* Register this allocation */
    pj_turn_srv_register_allocation(srv, alloc);

    /* Respond to ALLOCATE request */
    status = send_allocate_response(alloc, srv_sess, transport, rdata);
    if (status != PJ_SUCCESS)
	goto on_error;

    /* Done */
    pj_sockaddr_print(&alloc->relay.hkey.addr, str_tmp, 
//.........这里部分代码省略.........

pj_status_t create_test_server(pj_stun_config *stun_cfg,
			       pj_uint32_t flags,
			       const char *domain,
			       test_server **p_test_srv)
{
    pj_pool_t *pool;
    test_server *test_srv;
    pj_sockaddr hostip;
    char strbuf[100];
    pj_status_t status;

    PJ_ASSERT_RETURN(stun_cfg && domain && p_test_srv, PJ_EINVAL);

    status = pj_gethostip(pj_AF_INET(), &hostip);
    if (status != PJ_SUCCESS)
	return status;

    pool = pj_pool_create(mem, THIS_FILE, 512, 512, NULL);
    test_srv = (test_server*) PJ_POOL_ZALLOC_T(pool, test_server);
    test_srv->pool = pool;
    test_srv->flags = flags;
    test_srv->stun_cfg = stun_cfg;

    pj_strdup2(pool, &test_srv->domain, domain);
    test_srv->username = pj_str(TURN_USERNAME);
    test_srv->passwd = pj_str(TURN_PASSWD);

    pj_ioqueue_op_key_init(&test_srv->send_key, sizeof(test_srv->send_key));

    if (flags & CREATE_DNS_SERVER) {
	status = pj_dns_server_create(mem, test_srv->stun_cfg->ioqueue,
				      pj_AF_INET(), DNS_SERVER_PORT,
				      0, &test_srv->dns_server);
	if (status != PJ_SUCCESS) {
	    destroy_test_server(test_srv);
	    return status;
	}

	/* Add DNS A record for the domain, for fallback */
	if (flags & CREATE_A_RECORD_FOR_DOMAIN) {
	    pj_dns_parsed_rr rr;
	    pj_str_t res_name;
	    pj_in_addr ip_addr;

	    pj_strdup2(pool, &res_name, domain);
	    ip_addr = hostip.ipv4.sin_addr;
	    pj_dns_init_a_rr(&rr, &res_name, PJ_DNS_CLASS_IN, 60, &ip_addr);
	    pj_dns_server_add_rec(test_srv->dns_server, 1, &rr);
	}

    }

    if (flags & CREATE_STUN_SERVER) {
	pj_activesock_cb stun_sock_cb;
	pj_sockaddr bound_addr;

	pj_bzero(&stun_sock_cb, sizeof(stun_sock_cb));
	stun_sock_cb.on_data_recvfrom = &stun_on_data_recvfrom;

	pj_sockaddr_in_init(&bound_addr.ipv4, NULL, STUN_SERVER_PORT);

	status = pj_activesock_create_udp(pool, &bound_addr, NULL, 
					  test_srv->stun_cfg->ioqueue,
					  &stun_sock_cb, test_srv, 
					  &test_srv->stun_sock, NULL);
	if (status != PJ_SUCCESS) {
	    destroy_test_server(test_srv);
	    return status;
	}

	status = pj_activesock_start_recvfrom(test_srv->stun_sock, pool,
					      MAX_STUN_PKT, 0);
	if (status != PJ_SUCCESS) {
	    destroy_test_server(test_srv);
	    return status;
	}

	if (test_srv->dns_server && (flags & CREATE_STUN_SERVER_DNS_SRV)) {
	    pj_str_t res_name, target;
	    pj_dns_parsed_rr rr;
	    pj_in_addr ip_addr;

	    /* Add DNS entries:
	     *  _stun._udp.domain 60 IN SRV 0 0 PORT stun.domain.
	     *  stun.domain IN A 127.0.0.1
	     */
	    pj_ansi_snprintf(strbuf, sizeof(strbuf),
			     "_stun._udp.%s", domain);
	    pj_strdup2(pool, &res_name, strbuf);
	    pj_ansi_snprintf(strbuf, sizeof(strbuf),
			     "stun.%s", domain);
	    pj_strdup2(pool, &target, strbuf);
	    pj_dns_init_srv_rr(&rr, &res_name, PJ_DNS_CLASS_IN, 60, 0, 0, 
			       STUN_SERVER_PORT, &target);
	    pj_dns_server_add_rec(test_srv->dns_server, 1, &rr);

	    res_name = target;
	    ip_addr = hostip.ipv4.sin_addr;
	    pj_dns_init_a_rr(&rr, &res_name, PJ_DNS_CLASS_IN, 60, &ip_addr);
	    pj_dns_server_add_rec(test_srv->dns_server, 1, &rr);
//.........这里部分代码省略.........

/*
 * Create an SRTP media transport.
 */
PJ_DEF(pj_status_t) pjmedia_transport_srtp_create(
				       pjmedia_endpt *endpt,
				       pjmedia_transport *tp,
				       const pjmedia_srtp_setting *opt,
				       pjmedia_transport **p_tp)
{
    pj_pool_t *pool;
    transport_srtp *srtp;
    pj_status_t status;
    unsigned i;

    PJ_ASSERT_RETURN(endpt && tp && p_tp, PJ_EINVAL);

    /* Check crypto availability */
    if (opt && opt->crypto_count == 0 && 
	opt->use == PJMEDIA_SRTP_MANDATORY)
	return PJMEDIA_SRTP_ESDPREQCRYPTO;

    /* Check crypto */
    if (opt && opt->use != PJMEDIA_SRTP_DISABLED) {
	for (i=0; i < opt->crypto_count; ++i) {
	    int cs_idx = get_crypto_idx(&opt->crypto[i].name);

	    /* check crypto name */
	    if (cs_idx == -1)
		return PJMEDIA_SRTP_ENOTSUPCRYPTO;

	    /* check key length */
	    if (opt->crypto[i].key.slen && 
		opt->crypto[i].key.slen < 
		(pj_ssize_t)crypto_suites[cs_idx].cipher_key_len)
		return PJMEDIA_SRTP_EINKEYLEN;
	}
    }

    /* Init libsrtp. */
    status = pjmedia_srtp_init_lib();
    if (status != PJ_SUCCESS)
	return status;

    pool = pjmedia_endpt_create_pool(endpt, "srtp%p", 1000, 1000);
    srtp = PJ_POOL_ZALLOC_T(pool, transport_srtp);

    srtp->pool = pool;
    srtp->session_inited = PJ_FALSE;
    srtp->bypass_srtp = PJ_FALSE;
    srtp->probation_cnt = PROBATION_CNT_INIT;

    if (opt) {
	srtp->setting = *opt;
	if (opt->use == PJMEDIA_SRTP_DISABLED)
	    srtp->setting.crypto_count = 0;

	for (i=0; i < srtp->setting.crypto_count; ++i) {
	    int cs_idx = get_crypto_idx(&opt->crypto[i].name);
	    pj_str_t tmp_key = opt->crypto[i].key;

	    /* re-set crypto */
	    srtp->setting.crypto[i].name = pj_str(crypto_suites[cs_idx].name);
	    /* cut key length */
	    if (tmp_key.slen)
		tmp_key.slen = crypto_suites[cs_idx].cipher_key_len;
	    pj_strdup(pool, &srtp->setting.crypto[i].key, &tmp_key);
	}
    } else {
	pjmedia_srtp_setting_default(&srtp->setting);
    }

    status = pj_lock_create_recursive_mutex(pool, pool->obj_name, &srtp->mutex);
    if (status != PJ_SUCCESS) {
	pj_pool_release(pool);
	return status;
    }

    /* Initialize base pjmedia_transport */
    pj_memcpy(srtp->base.name, pool->obj_name, PJ_MAX_OBJ_NAME);
    if (tp)
	srtp->base.type = tp->type;
    else
	srtp->base.type = PJMEDIA_TRANSPORT_TYPE_UDP;
    srtp->base.op = &transport_srtp_op;

    /* Set underlying transport */
    srtp->member_tp = tp;

    /* Initialize peer's SRTP usage mode. */
    srtp->peer_use = srtp->setting.use;

    /* Done */
    *p_tp = &srtp->base;

    return PJ_SUCCESS;
}

/**
 * Create new session.
 */
PJ_DEF(pj_status_t) pjmedia_session_create( pjmedia_endpt *endpt, 
					    const pjmedia_session_info *si,
					    pjmedia_transport *transports[],
					    void *user_data,
					    pjmedia_session **p_session )
{
    pj_pool_t *pool;
    pjmedia_session *session;
    int i; /* Must be signed */
    pj_status_t status;

    /* Verify arguments. */
    PJ_ASSERT_RETURN(endpt && si && p_session, PJ_EINVAL);

    /* Create pool for the session. */
    pool = pjmedia_endpt_create_pool( endpt, "session", 
				      PJMEDIA_SESSION_SIZE, 
				      PJMEDIA_SESSION_INC);
    PJ_ASSERT_RETURN(pool != NULL, PJ_ENOMEM);

    session = PJ_POOL_ZALLOC_T(pool, pjmedia_session);
    session->pool = pool;
    session->endpt = endpt;
    session->stream_cnt = si->stream_cnt;
    session->user_data = user_data;

    /* Copy stream info (this simple memcpy may break sometime) */
    pj_memcpy(session->stream_info, si->stream_info,
	      si->stream_cnt * sizeof(pjmedia_stream_info));

    /*
     * Now create and start the stream!
     */
    for (i=0; i<(int)si->stream_cnt; ++i) {

	/* Create the stream */
	status = pjmedia_stream_create(endpt, session->pool,
				       &session->stream_info[i],
				       (transports?transports[i]:NULL),
				       session,
				       &session->stream[i]);
	if (status == PJ_SUCCESS)
	    status = pjmedia_stream_start(session->stream[i]);

	if (status != PJ_SUCCESS) {

	    for ( --i; i>=0; ++i) {
		pjmedia_stream_destroy(session->stream[i]);
	    }

	    pj_pool_release(session->pool);
	    return status;
	}
    }


    /* Done. */

    *p_session = session;
    return PJ_SUCCESS;
}

/*
 * Create the STUN transport using the specified configuration.
 */
PJ_DEF(pj_status_t) pj_stun_sock_create( pj_stun_config *stun_cfg,
					 const char *name,
					 int af,
					 const pj_stun_sock_cb *cb,
					 const pj_stun_sock_cfg *cfg,
					 void *user_data,
					 pj_stun_sock **p_stun_sock)
{
    pj_pool_t *pool;
    pj_stun_sock *stun_sock;
    pj_stun_sock_cfg default_cfg;
    unsigned i;
    pj_status_t status;

    PJ_ASSERT_RETURN(stun_cfg && cb && p_stun_sock, PJ_EINVAL);
    PJ_ASSERT_RETURN(af==pj_AF_INET()||af==pj_AF_INET6(), PJ_EAFNOTSUP);
    PJ_ASSERT_RETURN(!cfg || pj_stun_sock_cfg_is_valid(cfg), PJ_EINVAL);
    PJ_ASSERT_RETURN(cb->on_status, PJ_EINVAL);

    status = pj_stun_config_check_valid(stun_cfg);
    if (status != PJ_SUCCESS)
	return status;

    if (name == NULL)
	name = "stuntp%p";

    if (cfg == NULL) {
	pj_stun_sock_cfg_default(&default_cfg);
	cfg = &default_cfg;
    }


    /* Create structure */
    pool = pj_pool_create(stun_cfg->pf, name, 256, 512, NULL);
    stun_sock = PJ_POOL_ZALLOC_T(pool, pj_stun_sock);
    stun_sock->pool = pool;
    stun_sock->obj_name = pool->obj_name;
    stun_sock->user_data = user_data;
    stun_sock->af = af;
    stun_sock->sock_fd = PJ_INVALID_SOCKET;
    pj_memcpy(&stun_sock->stun_cfg, stun_cfg, sizeof(*stun_cfg));
    pj_memcpy(&stun_sock->cb, cb, sizeof(*cb));

    stun_sock->ka_interval = cfg->ka_interval;
    if (stun_sock->ka_interval == 0)
	stun_sock->ka_interval = PJ_STUN_KEEP_ALIVE_SEC;

    /* Create socket and bind socket */
    status = pj_sock_socket(af, pj_SOCK_DGRAM(), 0, &stun_sock->sock_fd);
    if (status != PJ_SUCCESS)
	goto on_error;

    /* Apply QoS, if specified */
    status = pj_sock_apply_qos2(stun_sock->sock_fd, cfg->qos_type,
				&cfg->qos_params, 2, stun_sock->obj_name,
				NULL);
    if (status != PJ_SUCCESS && !cfg->qos_ignore_error)
	goto on_error;

    /* Bind socket */
    if (pj_sockaddr_has_addr(&cfg->bound_addr)) {
	status = pj_sock_bind(stun_sock->sock_fd, &cfg->bound_addr,
			      pj_sockaddr_get_len(&cfg->bound_addr));
    } else {
	pj_sockaddr bound_addr;

	pj_sockaddr_init(af, &bound_addr, NULL, 0);
	status = pj_sock_bind(stun_sock->sock_fd, &bound_addr,
			      pj_sockaddr_get_len(&bound_addr));
    }

    if (status != PJ_SUCCESS)
	goto on_error;

    /* Create more useful information string about this transport */
#if 0
    {
	pj_sockaddr bound_addr;
	int addr_len = sizeof(bound_addr);

	status = pj_sock_getsockname(stun_sock->sock_fd, &bound_addr, 
				     &addr_len);
	if (status != PJ_SUCCESS)
	    goto on_error;

	stun_sock->info = pj_pool_alloc(pool, PJ_INET6_ADDRSTRLEN+10);
	pj_sockaddr_print(&bound_addr, stun_sock->info, 
			  PJ_INET6_ADDRSTRLEN, 3);
    }
#endif

    /* Init active socket configuration */
    {
	pj_activesock_cfg activesock_cfg;
	pj_activesock_cb activesock_cb;

	pj_activesock_cfg_default(&activesock_cfg);
//.........这里部分代码省略.........

/*
 * Create PRACK request for the incoming reliable provisional response.
 */
PJ_DEF(pj_status_t) pjsip_100rel_create_prack( pjsip_inv_session *inv,
					       pjsip_rx_data *rdata,
					       pjsip_tx_data **p_tdata)
{
    dlg_data *dd;
    uac_state_t *uac_state = NULL;
    const pj_str_t *to_tag = &rdata->msg_info.to->tag;
    pjsip_transaction *tsx;
    pjsip_msg *msg;
    pjsip_generic_string_hdr *rseq_hdr;
    pjsip_generic_string_hdr *rack_hdr;
    unsigned rseq;
    pj_str_t rack;
    char rack_buf[80];
    pjsip_tx_data *tdata;
    pj_status_t status;

    *p_tdata = NULL;

    dd = (dlg_data*) inv->dlg->mod_data[mod_100rel.mod.id];
    PJ_ASSERT_RETURN(dd != NULL, PJSIP_ENOTINITIALIZED);

    tsx = pjsip_rdata_get_tsx(rdata);
    msg = rdata->msg_info.msg;

    /* Check our assumptions */
    pj_assert( tsx->role == PJSIP_ROLE_UAC &&
	       tsx->method.id == PJSIP_INVITE_METHOD &&
	       msg->line.status.code > 100 &&
	       msg->line.status.code < 200);


    /* Get the RSeq header */
    rseq_hdr = (pjsip_generic_string_hdr*)
	       pjsip_msg_find_hdr_by_name(msg, &RSEQ, NULL);
    if (rseq_hdr == NULL) {
	PJ_LOG(4,(dd->inv->dlg->obj_name, 
		 "Ignoring 100rel response with no RSeq header"));
	return PJSIP_EMISSINGHDR;
    }
    rseq = (pj_uint32_t) pj_strtoul(&rseq_hdr->hvalue);

    /* Find UAC state for the specified call leg */
    uac_state = dd->uac_state_list;
    while (uac_state) {
	if (pj_stricmp(&uac_state->tag, to_tag)==0)
	    break;
	uac_state = uac_state->next;
    }

    /* Create new UAC state if we don't have one */
    if (uac_state == NULL) {
	uac_state = PJ_POOL_ZALLOC_T(dd->inv->dlg->pool, uac_state_t);
	uac_state->cseq = rdata->msg_info.cseq->cseq;
	uac_state->rseq = rseq - 1;
	pj_strdup(dd->inv->dlg->pool, &uac_state->tag, to_tag);
	uac_state->next = dd->uac_state_list;
	dd->uac_state_list = uac_state;
    }

    /* If this is from new INVITE transaction, reset UAC state. */
    if (rdata->msg_info.cseq->cseq != uac_state->cseq) {
	uac_state->cseq = rdata->msg_info.cseq->cseq;
	uac_state->rseq = rseq - 1;
    }

    /* Ignore provisional response retransmission */
    if (rseq <= uac_state->rseq) {
	/* This should have been handled before */
	return PJ_EIGNORED;

    /* Ignore provisional response with out-of-order RSeq */
    } else if (rseq != uac_state->rseq + 1) {
	PJ_LOG(4,(dd->inv->dlg->obj_name, 
		 "Ignoring 100rel response because RSeq jump "
		 "(expecting %u, got %u)",
		 uac_state->rseq+1, rseq));
	return PJ_EIGNORED;
    }

    /* Update our RSeq */
    uac_state->rseq = rseq;

    /* Create PRACK */
    status = pjsip_dlg_create_request(dd->inv->dlg, &pjsip_prack_method,
				      -1, &tdata);
    if (status != PJ_SUCCESS)
	return status;

    /* If this response is a forked response from a different call-leg,
     * update the req URI (https://trac.pjsip.org/repos/ticket/1364)
     */
    if (pj_stricmp(&uac_state->tag, &dd->inv->dlg->remote.info->tag)) {
	const pjsip_contact_hdr *mhdr;

	mhdr = (const pjsip_contact_hdr*)
	       pjsip_msg_find_hdr(rdata->msg_info.msg,
//.........这里部分代码省略.........

/*
 * This is a utility function to create PIDF message body from PJSIP
 * presence status (pjsip_pres_status).
 */
PJ_DEF(pj_status_t) pjsip_pres_create_pidf( pj_pool_t *pool,
					    const pjsip_pres_status *status,
					    const pj_str_t *entity,
					    pjsip_msg_body **p_body )
{
    pjpidf_pres *pidf;
    pjsip_msg_body *body;
    unsigned i;

    /* Create <presence>. */
    pidf = pjpidf_create(pool, entity);

    /* Create <tuple> */
    for (i=0; i<status->info_cnt; ++i) {

	pjpidf_tuple *pidf_tuple;
	pjpidf_status *pidf_status;
	pj_str_t id;

	/* Add tuple id. */
	if (status->info[i].id.slen == 0) {
	    /* xs:ID must start with letter */
	    //pj_create_unique_string(pool, &id);
	    id.ptr = (char*)pj_pool_alloc(pool, PJ_GUID_STRING_LENGTH+2);
	    id.ptr += 2;
	    pj_generate_unique_string(&id);
	    id.ptr -= 2;
	    id.ptr[0] = 'p';
	    id.ptr[1] = 'j';
	    id.slen += 2;
	} else {
	    id = status->info[i].id;
	}

	pidf_tuple = pjpidf_pres_add_tuple(pool, pidf, &id);

	/* Set <contact> */
	if (status->info[i].contact.slen)
	    pjpidf_tuple_set_contact(pool, pidf_tuple, 
				     &status->info[i].contact);


	/* Set basic status */
	pidf_status = pjpidf_tuple_get_status(pidf_tuple);
	pjpidf_status_set_basic_open(pidf_status, 
				     status->info[i].basic_open);

	/* Add <timestamp> if configured */
#if defined(PJSIP_PRES_PIDF_ADD_TIMESTAMP) && PJSIP_PRES_PIDF_ADD_TIMESTAMP
	if (PJSIP_PRES_PIDF_ADD_TIMESTAMP) {
	  char buf[50];
	  int tslen = 0;
	  pj_time_val tv;
	  pj_parsed_time pt;

	  pj_gettimeofday(&tv);
	  /* TODO: convert time to GMT! (unsupported by pjlib) */
	  pj_time_decode( &tv, &pt);

	  tslen = pj_ansi_snprintf(buf, sizeof(buf),
				   "%04d-%02d-%02dT%02d:%02d:%02d.%03dZ",
				   pt.year, pt.mon+1, pt.day, 
				   pt.hour, pt.min, pt.sec, pt.msec);
	  if (tslen > 0 && tslen < (int)sizeof(buf)) {
	      pj_str_t time = pj_str(buf);
	      pjpidf_tuple_set_timestamp(pool, pidf_tuple, &time);
	  }
	}
#endif
    }

    /* Create <person> (RPID) */
    if (status->info_cnt) {
	pjrpid_add_element(pidf, pool, 0, &status->info[0].rpid);
    }

    body = PJ_POOL_ZALLOC_T(pool, pjsip_msg_body);
    body->data = pidf;
    body->content_type.type = STR_APPLICATION;
    body->content_type.subtype = STR_PIDF_XML;
    body->print_body = &pres_print_body;
    body->clone_data = &xml_clone_data;

    *p_body = body;

    return PJ_SUCCESS;    
}

/*
 * Create server subscription.
 */
PJ_DEF(pj_status_t) pjsip_mwi_create_uas( pjsip_dialog *dlg,
					  const pjsip_evsub_user *user_cb,
					  pjsip_rx_data *rdata,
					  pjsip_evsub **p_evsub )
{
    pjsip_accept_hdr *accept;
    pjsip_event_hdr *event;
    pjsip_evsub *sub;
    pjsip_mwi *mwi;
    char obj_name[PJ_MAX_OBJ_NAME];
    pj_status_t status;

    /* Check arguments */
    PJ_ASSERT_RETURN(dlg && rdata && p_evsub, PJ_EINVAL);

    /* Must be request message */
    PJ_ASSERT_RETURN(rdata->msg_info.msg->type == PJSIP_REQUEST_MSG,
		     PJSIP_ENOTREQUESTMSG);

    /* Check that request is SUBSCRIBE */
    PJ_ASSERT_RETURN(pjsip_method_cmp(&rdata->msg_info.msg->line.req.method,
				      &pjsip_subscribe_method)==0,
		     PJSIP_SIMPLE_ENOTSUBSCRIBE);

    /* Check that Event header contains "mwi" */
    event = (pjsip_event_hdr*)
    	    pjsip_msg_find_hdr_by_name(rdata->msg_info.msg, &STR_EVENT, NULL);
    if (!event) {
	return PJSIP_ERRNO_FROM_SIP_STATUS(PJSIP_SC_BAD_REQUEST);
    }
    if (pj_stricmp(&event->event_type, &STR_MWI) != 0) {
	return PJSIP_ERRNO_FROM_SIP_STATUS(PJSIP_SC_BAD_EVENT);
    }

    /* Check that request contains compatible Accept header. */
    accept = (pjsip_accept_hdr*)
    	     pjsip_msg_find_hdr(rdata->msg_info.msg, PJSIP_H_ACCEPT, NULL);
    if (accept) {
	unsigned i;
	for (i=0; i<accept->count; ++i) {
	    if (pj_stricmp(&accept->values[i], &STR_APP_SIMPLE_SMS)==0) {
		break;
	    }
	}

	if (i==accept->count) {
	    /* Nothing is acceptable */
	    return PJSIP_ERRNO_FROM_SIP_STATUS(PJSIP_SC_NOT_ACCEPTABLE);
	}

    } else {
	/* No Accept header. 
	 * Assume client supports "application/simple-message-summary" 
	*/
    }

    /* Lock dialog */
    pjsip_dlg_inc_lock(dlg);


    /* Create server subscription */
    status = pjsip_evsub_create_uas( dlg, &mwi_user, rdata, 0, &sub);
    if (status != PJ_SUCCESS)
	goto on_return;

    /* Create server mwi subscription */
    mwi = PJ_POOL_ZALLOC_T(dlg->pool, pjsip_mwi);
    mwi->dlg = dlg;
    mwi->sub = sub;
    if (user_cb)
	pj_memcpy(&mwi->user_cb, user_cb, sizeof(pjsip_evsub_user));

    pj_ansi_snprintf(obj_name, PJ_MAX_OBJ_NAME, "mwibd%p", dlg->pool);
    mwi->body_pool = pj_pool_create(dlg->pool->factory, obj_name, 
				    512, 512, NULL);

    /* Attach to evsub */
    pjsip_evsub_set_mod_data(sub, mod_mwi.id, mwi);

    /* Done: */
    *p_evsub = sub;

on_return:
    pjsip_dlg_dec_lock(dlg);
    return status;
}

/* Create m=audio SDP media line */
PJ_DEF(pj_status_t) pjmedia_endpt_create_audio_sdp(pjmedia_endpt *endpt,
        pj_pool_t *pool,
        const pjmedia_sock_info *si,
        unsigned options,
        pjmedia_sdp_media **p_m)
{
    const pj_str_t STR_AUDIO = { "audio", 5 };
    pjmedia_sdp_media *m;
    pjmedia_sdp_attr *attr;
    unsigned i;
    unsigned max_bitrate = 0;
    pj_status_t status;

    PJ_UNUSED_ARG(options);

    /* Check that there are not too many codecs */
    PJ_ASSERT_RETURN(endpt->codec_mgr.codec_cnt <= PJMEDIA_MAX_SDP_FMT,
                     PJ_ETOOMANY);

    /* Create and init basic SDP media */
    m = PJ_POOL_ZALLOC_T(pool, pjmedia_sdp_media);
    status = init_sdp_media(m, pool, &STR_AUDIO, si);
    if (status != PJ_SUCCESS)
        return status;

    /* Add format, rtpmap, and fmtp (when applicable) for each codec */
    for (i=0; i<endpt->codec_mgr.codec_cnt; ++i) {

        pjmedia_codec_info *codec_info;
        pjmedia_sdp_rtpmap rtpmap;
        char tmp_param[3];
        pjmedia_codec_param codec_param;
        pj_str_t *fmt;

        if (endpt->codec_mgr.codec_desc[i].prio == PJMEDIA_CODEC_PRIO_DISABLED)
            break;

        codec_info = &endpt->codec_mgr.codec_desc[i].info;
        pjmedia_codec_mgr_get_default_param(&endpt->codec_mgr, codec_info,
                                            &codec_param);
        fmt = &m->desc.fmt[m->desc.fmt_count++];

        fmt->ptr = (char*) pj_pool_alloc(pool, 8);
        fmt->slen = pj_utoa(codec_info->pt, fmt->ptr);

        rtpmap.pt = *fmt;
        rtpmap.enc_name = codec_info->encoding_name;

#if defined(PJMEDIA_HANDLE_G722_MPEG_BUG) && (PJMEDIA_HANDLE_G722_MPEG_BUG != 0)
        if (codec_info->pt == PJMEDIA_RTP_PT_G722)
            rtpmap.clock_rate = 8000;
        else
            rtpmap.clock_rate = codec_info->clock_rate;
#else
        rtpmap.clock_rate = codec_info->clock_rate;
#endif

        /* For audio codecs, rtpmap parameters denotes the number
         * of channels, which can be omited if the value is 1.
         */
        if (codec_info->type == PJMEDIA_TYPE_AUDIO &&
                codec_info->channel_cnt > 1)
        {
            /* Can only support one digit channel count */
            pj_assert(codec_info->channel_cnt < 10);

            tmp_param[0] = (char)('0' + codec_info->channel_cnt);

            rtpmap.param.ptr = tmp_param;
            rtpmap.param.slen = 1;

        } else {
            rtpmap.param.ptr = "";
            rtpmap.param.slen = 0;
        }

        if (codec_info->pt >= 96 || pjmedia_add_rtpmap_for_static_pt) {
            pjmedia_sdp_rtpmap_to_attr(pool, &rtpmap, &attr);
            m->attr[m->attr_count++] = attr;
        }

        /* Add fmtp params */
        if (codec_param.setting.dec_fmtp.cnt > 0) {
            enum { MAX_FMTP_STR_LEN = 160 };
            char buf[MAX_FMTP_STR_LEN];
            unsigned buf_len = 0, i;
            pjmedia_codec_fmtp *dec_fmtp = &codec_param.setting.dec_fmtp;

            /* Print codec PT */
            buf_len += pj_ansi_snprintf(buf,
                                        MAX_FMTP_STR_LEN - buf_len,
                                        "%d",
                                        codec_info->pt);

            for (i = 0; i < dec_fmtp->cnt; ++i) {
                pj_size_t test_len = 2;

                /* Check if buf still available */
                test_len = dec_fmtp->param[i].val.slen +
//.........这里部分代码省略.........

/* Reinitialize outgoing request after 401/407 response is received.
 * The purpose of this function is:
 *  - to add a Authorization/Proxy-Authorization header.
 *  - to put the newly created Authorization/Proxy-Authorization header
 *    in cached_list.
 */
PJ_DEF(pj_status_t) pjsip_auth_clt_reinit_req(	pjsip_auth_clt_sess *sess,
						const pjsip_rx_data *rdata,
						pjsip_tx_data *old_request,
						pjsip_tx_data **new_request )
{
    pjsip_tx_data *tdata;
    const pjsip_hdr *hdr;
    unsigned chal_cnt;
    pjsip_via_hdr *via;
    pj_status_t status;

    PJ_ASSERT_RETURN(sess && rdata && old_request && new_request,
		     PJ_EINVAL);
    PJ_ASSERT_RETURN(sess->pool, PJSIP_ENOTINITIALIZED);
    PJ_ASSERT_RETURN(rdata->msg_info.msg->type == PJSIP_RESPONSE_MSG,
		     PJSIP_ENOTRESPONSEMSG);
    PJ_ASSERT_RETURN(old_request->msg->type == PJSIP_REQUEST_MSG,
		     PJSIP_ENOTREQUESTMSG);
    PJ_ASSERT_RETURN(rdata->msg_info.msg->line.status.code == 401 ||
		     rdata->msg_info.msg->line.status.code == 407,
		     PJSIP_EINVALIDSTATUS);

    tdata = old_request;
    tdata->auth_retry = PJ_FALSE;

    /*
     * Respond to each authentication challenge.
     */
    hdr = rdata->msg_info.msg->hdr.next;
    chal_cnt = 0;
    while (hdr != &rdata->msg_info.msg->hdr) {
	pjsip_cached_auth *cached_auth;
	const pjsip_www_authenticate_hdr *hchal;
	pjsip_authorization_hdr *hauth;

	/* Find WWW-Authenticate or Proxy-Authenticate header. */
	while (hdr != &rdata->msg_info.msg->hdr &&
	       hdr->type != PJSIP_H_WWW_AUTHENTICATE &&
	       hdr->type != PJSIP_H_PROXY_AUTHENTICATE)
	{
	    hdr = hdr->next;
	}
	if (hdr == &rdata->msg_info.msg->hdr)
	    break;

	hchal = (const pjsip_www_authenticate_hdr*) hdr;
	++chal_cnt;

	/* Find authentication session for this realm, create a new one
	 * if not present.
	 */
	cached_auth = find_cached_auth(sess, &hchal->challenge.common.realm );
	if (!cached_auth) {
	    cached_auth = PJ_POOL_ZALLOC_T( sess->pool, pjsip_cached_auth);
	    pj_strdup( sess->pool, &cached_auth->realm, &hchal->challenge.common.realm);
	    cached_auth->is_proxy = (hchal->type == PJSIP_H_PROXY_AUTHENTICATE);
#	    if (PJSIP_AUTH_HEADER_CACHING)
	    {
		pj_list_init(&cached_auth->cached_hdr);
	    }
#	    endif
	    pj_list_insert_before( &sess->cached_auth, cached_auth );
	}

	/* Create authorization header for this challenge, and update
	 * authorization session.
	 */
	status = process_auth( tdata->pool, hchal, tdata->msg->line.req.uri, 
			       tdata, sess, cached_auth, &hauth);
	if (status != PJ_SUCCESS)
	    return status;

	/* Add to the message. */
	pjsip_msg_add_hdr(tdata->msg, (pjsip_hdr*)hauth);

	/* Process next header. */
	hdr = hdr->next;
    }

    /* Check if challenge is present */
    if (chal_cnt == 0)
	return PJSIP_EAUTHNOCHAL;

    /* Remove branch param in Via header. */
    via = (pjsip_via_hdr*) pjsip_msg_find_hdr(tdata->msg, PJSIP_H_VIA, NULL);
    via->branch_param.slen = 0;

    /* Restore strict route set.
     * See http://trac.pjsip.org/repos/ticket/492
     */
    pjsip_restore_strict_route_set(tdata);

    /* Must invalidate the message! */
    pjsip_tx_data_invalidate_msg(tdata);
//.........这里部分代码省略.........

/*
 * The public API to invoke DNS SRV resolution.
 */
PJ_DEF(pj_status_t) pj_dns_srv_resolve( const pj_str_t *domain_name,
                                        const pj_str_t *res_name,
                                        unsigned def_port,
                                        pj_pool_t *pool,
                                        pj_dns_resolver *resolver,
                                        unsigned option,
                                        void *token,
                                        pj_dns_srv_resolver_cb *cb,
                                        pj_dns_srv_async_query **p_query)
{
    int len;
    pj_str_t target_name;
    pj_dns_srv_async_query *query_job;
    pj_status_t status;

    PJ_ASSERT_RETURN(domain_name && domain_name->slen &&
                     res_name && res_name->slen &&
                     pool && resolver && cb, PJ_EINVAL);

    /* Build full name */
    len = domain_name->slen + res_name->slen + 2;
    target_name.ptr = (char*) pj_pool_alloc(pool, len);
    pj_strcpy(&target_name, res_name);
    if (res_name->ptr[res_name->slen-1] != '.')
        pj_strcat2(&target_name, ".");
    len = target_name.slen;
    pj_strcat(&target_name, domain_name);
    target_name.ptr[target_name.slen] = '\0';


    /* Build the query_job state */
    query_job = PJ_POOL_ZALLOC_T(pool, pj_dns_srv_async_query);
    query_job->common.type = PJ_DNS_TYPE_SRV;
    query_job->objname = target_name.ptr;
    query_job->resolver = resolver;
    query_job->token = token;
    query_job->cb = cb;
    query_job->option = option;
    query_job->full_name = target_name;
    query_job->domain_part.ptr = target_name.ptr + len;
    query_job->domain_part.slen = target_name.slen - len;
    query_job->def_port = (pj_uint16_t)def_port;

    /* Start the asynchronous