static pj_status_t g729_open(pjmedia_codec *codec,
			     pjmedia_codec_param *attr )
{
    struct g729_private *priv = (struct g729_private*) codec->codec_data;
    pj_pool_t *pool;

    priv->pt = attr->info.pt;
    pool = priv->pool;

  /* PREPARING THE ENCODER */
  priv->encoder = pj_pool_zalloc(pool, g729a_enc_mem_size());
	if (!priv->encoder)
		return PJMEDIA_CODEC_EFAILED;
    if (!g729a_enc_init(priv->encoder))
    	return PJMEDIA_CODEC_EFAILED;

    /* PREPARING THE DECODER */
    priv->decoder = pj_pool_zalloc(pool, g729a_dec_mem_size());
	if (!priv->decoder)
		return PJMEDIA_CODEC_EFAILED;
    if (!g729a_dec_init(priv->decoder))
		return PJMEDIA_CODEC_EFAILED;

#if !PLC_DISABLED
    priv->plc_enabled = (attr->setting.plc != 0);
#endif
    priv->vad_enabled = (attr->setting.vad != 0);
    return PJ_SUCCESS;
}

/*
 * Create the ZRTP transport.
 */
PJ_DEF(pj_status_t) pjmedia_transport_zrtp_create(pjmedia_endpt *endpt,
        const char *name,
        pjmedia_transport *transport,
        pjmedia_transport **p_tp,
        pj_bool_t close_slave)
{
    pj_pool_t *pool;
    struct tp_zrtp *zrtp;
    pj_status_t rc;

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

    /* Create the pool and initialize the adapter structure */
    pool = pjmedia_endpt_create_pool(endpt, name, 5*1024, 512);
    zrtp = PJ_POOL_ZALLOC_T(pool, struct tp_zrtp);
    zrtp->pool = pool;
    pj_ansi_strncpy(zrtp->base.name, pool->obj_name,
                    sizeof(zrtp->base.name));
    zrtp->base.type = (pjmedia_transport_type)
                      (PJMEDIA_TRANSPORT_TYPE_USER + 2);
    zrtp->base.op = &tp_zrtp_op;

#ifndef DYNAMIC_TIMER
    if (timer_pool == NULL)
    {
        timer_pool = pjmedia_endpt_create_pool(endpt, "zrtp_timer", 256, 256);
        rc = timer_initialize();
        if (rc != PJ_SUCCESS)
        {
            pj_pool_release(timer_pool);
            pj_pool_release(zrtp->pool);
            return rc;
        }
    }
#else
    zrtp->timer_heap = pjsip_endpt_get_timer_heap(pjsua_var.endpt);
#endif

    /* Create the empty wrapper */
    zrtp->zrtpCtx = zrtp_CreateWrapper();

    /* Initialize standard values */
    zrtp->clientIdString = clientId;    /* Set standard name */
    zrtp->zrtpSeq = 1;                  /* TODO: randomize */
    rc = pj_mutex_create_simple(zrtp->pool, "zrtp", &zrtp->zrtpMutex);
    zrtp->zrtpBuffer = pj_pool_zalloc(pool, MAX_ZRTP_SIZE);
    zrtp->sendBuffer = pj_pool_zalloc(pool, MAX_RTP_BUFFER_LEN);
    zrtp->sendBufferCtrl = pj_pool_zalloc(pool, MAX_RTCP_BUFFER_LEN);

    zrtp->slave_tp = transport;
    zrtp->close_slave = close_slave;
    zrtp->mitmMode = PJ_FALSE;

    /* Done */
    zrtp->refcount++;
    *p_tp = &zrtp->base;
    return PJ_SUCCESS;
}

/*
 * Create the splitter/combiner.
 */
PJ_DEF(pj_status_t) pjmedia_splitcomb_create( pj_pool_t *pool,
					      unsigned clock_rate,
					      unsigned channel_count,
					      unsigned samples_per_frame,
					      unsigned bits_per_sample,
					      unsigned options,
					      pjmedia_port **p_splitcomb)
{
    const pj_str_t name = pj_str("splitcomb");
    struct splitcomb *sc;

    /* Sanity check */
    PJ_ASSERT_RETURN(pool && clock_rate && channel_count &&
		     samples_per_frame && bits_per_sample &&
		     p_splitcomb, PJ_EINVAL);

    /* Only supports 16 bits per sample */
    PJ_ASSERT_RETURN(bits_per_sample == 16, PJ_EINVAL);

    *p_splitcomb = NULL;

    /* Create the splitter/combiner structure */
    sc = pj_pool_zalloc(pool, sizeof(struct splitcomb));
    PJ_ASSERT_RETURN(sc != NULL, PJ_ENOMEM);

    /* Create temporary buffers */
    sc->get_buf = pj_pool_alloc(pool, samples_per_frame * 
				      sizeof(TMP_SAMP_TYPE) /
				      channel_count);
    PJ_ASSERT_RETURN(sc->get_buf, PJ_ENOMEM);

    sc->put_buf = pj_pool_alloc(pool, samples_per_frame * 
				      sizeof(TMP_SAMP_TYPE) /
				      channel_count);
    PJ_ASSERT_RETURN(sc->put_buf, PJ_ENOMEM);


    /* Save options */
    sc->options = options;

    /* Initialize port */
    pjmedia_port_info_init(&sc->base.info, &name, SIGNATURE, clock_rate,
			   channel_count, bits_per_sample, samples_per_frame);

    sc->base.put_frame = &put_frame;
    sc->base.get_frame = &get_frame;
    sc->base.on_destroy = &on_destroy;

    /* Init ports array */
    sc->port_desc = pj_pool_zalloc(pool, channel_count*sizeof(*sc->port_desc));

    /* Done for now */
    *p_splitcomb = &sc->base;

    return PJ_SUCCESS;
}

/*
 * Create a media port to generate sine wave samples.
 */
static pj_status_t create_sine_port(pj_pool_t *pool,
				    unsigned sampling_rate,
				    unsigned channel_count,
				    pjmedia_port **p_port)
{
    pjmedia_port *port;
    unsigned i;
    unsigned count;
    port_data *sine;

    PJ_ASSERT_RETURN(pool && channel_count > 0 && channel_count <= 2, 
		     PJ_EINVAL);

    port = pj_pool_zalloc(pool, sizeof(pjmedia_port));
    PJ_ASSERT_RETURN(port != NULL, PJ_ENOMEM);

    /* Fill in port info. */
    port->info.bits_per_sample = 16;
    port->info.channel_count = channel_count;
    port->info.encoding_name = pj_str("pcm");
    port->info.has_info = 1;
    port->info.name = pj_str("sine generator");
    port->info.need_info = 0;
    port->info.pt = 0xFF;
    port->info.clock_rate = sampling_rate;
    port->info.samples_per_frame = sampling_rate * 20 / 1000 * channel_count;
    port->info.bytes_per_frame = port->info.samples_per_frame * 2;
    port->info.type = PJMEDIA_TYPE_AUDIO;
    
    /* Set the function to feed frame */
    port->get_frame = &sine_get_frame;

    /* Create sine port data */
    port->port_data.pdata = sine = pj_pool_zalloc(pool, sizeof(port_data));

    /* Create samples */
    count = port->info.samples_per_frame / channel_count;
    sine->samples = pj_pool_alloc(pool, count * sizeof(pj_int16_t));
    PJ_ASSERT_RETURN(sine->samples != NULL, PJ_ENOMEM);

    /* initialise sinusoidal wavetable */
    for( i=0; i<count; i++ )
    {
        sine->samples[i] = (pj_int16_t) (10000.0 * 
		sin(((double)i/(double)count) * M_PI * 8.) );
    }

    *p_port = port;

    return PJ_SUCCESS;
}

/*
 * Allocate a new iLBC codec instance.
 */
static pj_status_t ilbc_alloc_codec(pjmedia_codec_factory *factory, 
				    const pjmedia_codec_info *id,
				    pjmedia_codec **p_codec)
{
    pj_pool_t *pool;
    struct ilbc_codec *codec;

    PJ_ASSERT_RETURN(factory && id && p_codec, PJ_EINVAL);
    PJ_ASSERT_RETURN(factory == &ilbc_factory.base, PJ_EINVAL);

    pool = pjmedia_endpt_create_pool(ilbc_factory.endpt, "iLBC%p",
				     2000, 2000);
    PJ_ASSERT_RETURN(pool != NULL, PJ_ENOMEM);

    codec = pj_pool_zalloc(pool, sizeof(struct ilbc_codec));
    codec->base.op = &ilbc_op;
    codec->base.factory = factory;
    codec->pool = pool;

    pj_ansi_snprintf(codec->obj_name,  sizeof(codec->obj_name),
		     "ilbc%p", codec);

    *p_codec = &codec->base;
    return PJ_SUCCESS;
}

PJ_DEF(pj_status_t) pjmedia_silence_det_create( pj_pool_t *pool,
						unsigned clock_rate,
						unsigned samples_per_frame,
						pjmedia_silence_det **p_sd)
{
    pjmedia_silence_det *sd;

    PJ_ASSERT_RETURN(pool && p_sd, PJ_EINVAL);

    sd = pj_pool_zalloc(pool, sizeof(struct pjmedia_silence_det));

    pj_ansi_strncpy(sd->objname, THIS_FILE, PJ_MAX_OBJ_NAME);
    sd->objname[PJ_MAX_OBJ_NAME-1] = '\0';

    sd->ptime = samples_per_frame * 1000 / clock_rate;
    sd->signal_cnt = 0;
    sd->silence_cnt = 0;
    sd->weakest_signal = 0xFFFFFFFFUL;
    sd->loudest_silence = 0;
     
    /* Default settings */
    pjmedia_silence_det_set_params(sd, -1, -1, -1);

    /* Restart in fixed, silent mode */
    sd->in_talk = PJ_FALSE;
    pjmedia_silence_det_set_adaptive( sd, -1 );

    *p_sd = sd;
    return PJ_SUCCESS;
}

PJ_DEF(pj_status_t) pjmedia_null_port_create( pj_pool_t *pool,
					      unsigned sampling_rate,
					      unsigned channel_count,
					      unsigned samples_per_frame,
					      unsigned bits_per_sample,
					      pjmedia_port **p_port )
{
    pjmedia_port *port;
    const pj_str_t name = pj_str("null-port");

    PJ_ASSERT_RETURN(pool && p_port, PJ_EINVAL);

    port = pj_pool_zalloc(pool, sizeof(pjmedia_port));
    PJ_ASSERT_RETURN(pool != NULL, PJ_ENOMEM);

    pjmedia_port_info_init(&port->info, &name, SIGNATURE, sampling_rate,
			   channel_count, bits_per_sample, samples_per_frame);

    port->get_frame = &null_get_frame;
    port->put_frame = &null_put_frame;
    port->on_destroy = &null_on_destroy;


    *p_port = port;
    
    return PJ_SUCCESS;
}

static int xml_parse_print_test(const char *doc)
{
    pj_str_t msg;
    pj_pool_t *pool;
    pj_xml_node *root;
    char *output;
    int output_len;

    pool = pj_pool_create(mem, "xml", 4096, 1024, NULL);
    pj_strdup2(pool, &msg, doc);
    root = pj_xml_parse(pool, msg.ptr, msg.slen);
    if (!root) {
	PJ_LOG(1, (THIS_FILE, "  Error: unable to parse XML"));
	return -10;
    }

    output = (char*)pj_pool_zalloc(pool, msg.slen + 512);
    output_len = pj_xml_print(root, output, msg.slen+512, PJ_TRUE);
    if (output_len < 1) {
	PJ_LOG(1, (THIS_FILE, "  Error: buffer too small to print XML file"));
	return -20;
    }
    output[output_len] = '\0';


    pj_pool_release(pool);
    return 0;
}

/*
 * Create. 
 */
PJ_DEF(pj_status_t) echo_supp_create( pj_pool_t *pool,
				      unsigned clock_rate,
				      unsigned samples_per_frame,
				      unsigned tail_ms,
				      unsigned latency_ms,
				      unsigned options,
				      void **p_state )
{
    echo_supp *ec;
    pj_status_t status;

    PJ_UNUSED_ARG(clock_rate);
    PJ_UNUSED_ARG(options);
    PJ_UNUSED_ARG(latency_ms);

    ec = pj_pool_zalloc(pool, sizeof(struct echo_supp));
    ec->samples_per_frame = samples_per_frame;
    ec->tail_ms = tail_ms;

    status = pjmedia_silence_det_create(pool, clock_rate, samples_per_frame,
					&ec->sd);
    if (status != PJ_SUCCESS)
	return status;

    pjmedia_silence_det_set_name(ec->sd, "ecsu%p");
    pjmedia_silence_det_set_adaptive(ec->sd, PJMEDIA_ECHO_SUPPRESS_THRESHOLD);
    pjmedia_silence_det_set_params(ec->sd, 100, 500, 3000);

    *p_state = ec;
    return PJ_SUCCESS;
}

/*
 * Make outgoing call.
 */
static pj_status_t make_call(const pj_str_t *dst_uri)
{
    struct call *call;
    pjsip_dialog *dlg;
    pjmedia_sdp_session *sdp;
    pjsip_tx_data *tdata;
    pj_status_t status;


    /* Create UAC dialog */
    status = pjsip_dlg_create_uac( pjsip_ua_instance(), 
				   &app.local_uri,	/* local URI	    */
				   &app.local_contact,	/* local Contact    */
				   dst_uri,		/* remote URI	    */
				   dst_uri,		/* remote target    */
				   &dlg);		/* dialog	    */
    if (status != PJ_SUCCESS) {
	return status;
    }

    /* Create call */
    call = pj_pool_zalloc(dlg->pool, sizeof(struct call));

    /* Create SDP */
    if (app.real_sdp) {
	status = pjmedia_endpt_create_sdp(app.med_endpt, dlg->pool, 1, 
					  app.skinfo, &sdp);
	if (status != PJ_SUCCESS) {
	    pjsip_dlg_terminate(dlg);
	    return status;
	}
    } else
	sdp = app.dummy_sdp;

    /* Create the INVITE session. */
    status = pjsip_inv_create_uac( dlg, sdp, 0, &call->inv);
    if (status != PJ_SUCCESS) {
	pjsip_dlg_terminate(dlg);
	return status;
    }


    /* Create initial INVITE request.
     * This INVITE request will contain a perfectly good request and 
     * an SDP body as well.
     */
    status = pjsip_inv_invite(call->inv, &tdata);
    PJ_ASSERT_RETURN(status == PJ_SUCCESS, status);


    /* Send initial INVITE request. 
     * From now on, the invite session's state will be reported to us
     * via the invite session callbacks.
     */
    status = pjsip_inv_send_msg(call->inv, tdata);
    PJ_ASSERT_RETURN(status == PJ_SUCCESS, status);


    return PJ_SUCCESS;
}

/*
 * Create PLC session. This function will select the PLC algorithm to
 * use based on the arguments.
 */
PJ_DEF(pj_status_t) pjmedia_plc_create( pj_pool_t *pool,
					unsigned clock_rate,
					unsigned samples_per_frame,
					unsigned options,
					pjmedia_plc **p_plc)
{
    pjmedia_plc *plc;

    PJ_ASSERT_RETURN(pool && clock_rate && samples_per_frame && p_plc,
		     PJ_EINVAL);
    PJ_ASSERT_RETURN(options == 0, PJ_EINVAL);

    PJ_UNUSED_ARG(options);

    plc = pj_pool_zalloc(pool, sizeof(pjmedia_plc));

    if (0)
	;
#if defined(PJMEDIA_HAS_STEVEU_PLC) && PJMEDIA_HAS_STEVEU_PLC!=0
    else if (clock_rate == 8000)
	plc->op = &plc_steveu;
#endif
    else
	plc->op = &plc_replay;

    plc->obj = plc->op->plc_create(pool, clock_rate, samples_per_frame);

    *p_plc = plc;

    return PJ_SUCCESS;
}

/*
 * Create a media port to generate sine wave samples.
 */
static pj_status_t create_sine_port(pj_pool_t *pool,
				    unsigned sampling_rate,
				    unsigned channel_count,
				    pjmedia_port **p_port)
{
    pjmedia_port *port;
    unsigned i;
    unsigned count;
    pj_str_t name;
    port_data *sine;

    PJ_ASSERT_RETURN(pool && channel_count > 0 && channel_count <= 2, 
		     PJ_EINVAL);

    port = pj_pool_zalloc(pool, sizeof(pjmedia_port));
    PJ_ASSERT_RETURN(port != NULL, PJ_ENOMEM);

    /* Fill in port info. */
    name = pj_str("sine generator");
    pjmedia_port_info_init(&port->info, &name,
                           PJMEDIA_SIG_CLASS_PORT_AUD('s', 'i'),
			   sampling_rate,
			   channel_count,
			   16, sampling_rate * 20 / 1000 * channel_count);
    
    /* Set the function to feed frame */
    port->get_frame = &sine_get_frame;

    /* Create sine port data */
    port->port_data.pdata = sine = pj_pool_zalloc(pool, sizeof(port_data));

    /* Create samples */
    count = PJMEDIA_PIA_SPF(&port->info) / channel_count;
    sine->samples = pj_pool_alloc(pool, count * sizeof(pj_int16_t));
    PJ_ASSERT_RETURN(sine->samples != NULL, PJ_ENOMEM);

    /* initialise sinusoidal wavetable */
    for( i=0; i<count; i++ )
    {
        sine->samples[i] = (pj_int16_t) (10000.0 * 
		sin(((double)i/(double)count) * M_PI * 8.) );
    }

    *p_port = port;

    return PJ_SUCCESS;
}

void Sdp::setTelephoneEventRtpmap(pjmedia_sdp_media *med)
{
    pjmedia_sdp_attr *attr_rtpmap = NULL;
    pjmedia_sdp_attr *attr_fmtp = NULL;

    attr_rtpmap = static_cast<pjmedia_sdp_attr *>(pj_pool_zalloc(memPool_, sizeof(pjmedia_sdp_attr)));
    attr_rtpmap->name = pj_str((char *) "rtpmap");
    attr_rtpmap->value = pj_str((char *) "101 telephone-event/8000");

    med->attr[med->attr_count++] = attr_rtpmap;

    attr_fmtp = static_cast<pjmedia_sdp_attr *>(pj_pool_zalloc(memPool_, sizeof(pjmedia_sdp_attr)));
    attr_fmtp->name = pj_str((char *) "fmtp");
    attr_fmtp->value = pj_str((char *) "101 0-15");

    med->attr[med->attr_count++] = attr_fmtp;
}

/*
 * Create the echo canceller.
 */
pjs_echo_canceller::pjs_echo_canceller(pj_pool_t *pool_, unsigned clock_rate,
		unsigned samples_per_frame_, unsigned tail_ms, unsigned latency_ms,
		unsigned options) {
	int sampling_rate = clock_rate;
	unsigned ptime, lat_cnt;
	unsigned delay_buf_opt = 0;

	lat_ready = PJ_FALSE;
	/* Create new pool and instantiate and init the EC */
	pool = pj_pool_create(pool_->factory, "ec%p", 256, 256, NULL);
	lock = new PPJ_SemaphoreLock(pool, NULL, 1, 1);
	samples_per_frame = samples_per_frame_;
	frm_buf = (pj_int16_t*) pj_pool_alloc(pool, samples_per_frame << 1);

    state = speex_echo_state_init(samples_per_frame,
    					clock_rate * tail_ms / 1000);

    speex_echo_ctl(state, SPEEX_ECHO_SET_SAMPLING_RATE,
		   &sampling_rate);

    preprocess = speex_preprocess_state_init(samples_per_frame,
						   clock_rate);
    tmp_frame = (pj_int16_t*) pj_pool_zalloc(pool, 2*samples_per_frame);

    speex_preprocess_ctl(preprocess, SPEEX_PREPROCESS_SET_ECHO_STATE,
 			state);

	pj_list_init(&lat_buf);
	pj_list_init(&lat_free);

	PJ_LOG(5, (THIS_FILE, "Creating echo canceler"));

	/* Create latency buffers */
	ptime = samples_per_frame * 1000 / clock_rate;
	if (latency_ms < ptime) {
		/* Give at least one frame delay to simplify programming */
		latency_ms = ptime;
	}
	lat_cnt = latency_ms / ptime;
	while (lat_cnt--) {
		struct frame *frm;

		frm = (struct frame*) pj_pool_alloc(pool,
				(samples_per_frame << 1) + sizeof(struct frame));
		pj_list_push_back(&lat_free, frm);
	}

	/* Create delay buffer to compensate drifts */
	if (options & PJMEDIA_ECHO_USE_SIMPLE_FIFO)
		delay_buf_opt |= PJMEDIA_DELAY_BUF_SIMPLE_FIFO;
	pjmedia_delay_buf_create(pool, NULL, clock_rate, samples_per_frame,
			1, (PJMEDIA_SOUND_BUFFER_COUNT + 1) * ptime, delay_buf_opt,
			&delay_buf);
	PJ_LOG(4, (THIS_FILE, "ECHO canceller created, clock_rate=%d, channel=%d, "
	"samples per frame=%d, tail length=%d ms, "
	"latency=%d ms", clock_rate, 1, samples_per_frame, tail_ms, latency_ms));
}

PJ_DEF(int) jitter_buffer_create(Jitter_Buffer ** jitter_buffer, pj_pool_t *pool,
    int max_number_of_frames, NACK_MODE nack_mode, 
    int low_rtt_threshold_ms, int high_rtt_threshold_ms) {
    pj_assert(low_rtt_threshold_ms <= high_rtt_threshold_ms);
    //alloc jitter buffer
    Jitter_Buffer *jitter_buffer_internal = (Jitter_Buffer*)pj_pool_zalloc(pool, sizeof(Jitter_Buffer));
    //init list alloc
    list_alloc_init(&jitter_buffer_internal->frame_alloc, pool);
    list_alloc_init(&jitter_buffer_internal->packet_alloc, pool);
    //init frame list, don't call frame_buffer_init, 
    //since the header is not used as a real frame
    pj_list_init(&jitter_buffer_internal->frameList);
    pj_list_init(&jitter_buffer_internal->decodingFrameList);
    //init frame number
    jitter_buffer_internal->max_number_of_frames = max_number_of_frames 
            < MIN_NUM_OF_FRAMES? MIN_NUM_OF_FRAMES : max_number_of_frames;
    jitter_buffer_internal->number_of_frames = 0;
    //init decode state
    decode_state_init(&jitter_buffer_internal->decode_state);
    //init jitter estimator
    jitter_estimator_init(&jitter_buffer_internal->jitter_estimator);
    //init inter_frame_delay
    inter_frame_delay_init(&jitter_buffer_internal->inter_frame_delay);
    //init rtt
    jitter_buffer_internal->rttMs = DEFAULT_RTT_MS;
    //init nack
    if(high_rtt_threshold_ms != -1) 
        jitter_buffer_internal->rttMs = 0;
    jitter_buffer_internal->nack_mode = nack_mode;
    jitter_buffer_internal->low_rtt_threshold_ms = low_rtt_threshold_ms;
    jitter_buffer_internal->high_rtt_threshold_ms = high_rtt_threshold_ms;
    jitter_buffer_internal->nack_seq_num = 0;
    //init event
    if(event_create(&jitter_buffer_internal->frame_event) != 0) {
        return -1;
    }
    if(event_create(&jitter_buffer_internal->packet_event) != 0)
        return -1;
    
    //not running
    jitter_buffer_internal->running = PJ_FALSE;
    //first packet 
    jitter_buffer_internal->first_packet = PJ_FALSE;
    //the first frame must be key frame
    jitter_buffer_internal->waiting_for_key_frame = PJ_TRUE;
    //waiting for completed frame
    jitter_buffer_internal->waiting_for_completed_frame.timestamp = 0;
    jitter_buffer_internal->waiting_for_completed_frame.frame_size = 0;
    jitter_buffer_internal->waiting_for_completed_frame.latest_packet_timestamp = -1;
    //init mutex
    if(pj_mutex_create_simple(pool, NULL, &jitter_buffer_internal->jb_mutex) != PJ_SUCCESS)
        return -1;
    //ret
    *jitter_buffer = jitter_buffer_internal;
    return 0;
    
}

void queue_init(queue_t *queue, int cap, int data_size, pj_pool_t *p_mempool) {
    queue->capacity = cap;
    queue->buffer = pj_pool_zalloc(p_mempool, sizeof(void *) * cap);
    queue->size = 0;
    queue->in = 0;
    queue->out = 0;

//#define QEPOOL_SIZE(queue) (5*queue->capacity)
//    qepool_init(&(queue->qepool), QEPOOL_SIZE(queue), data_size, p_mempool);
    pthread_mutex_init(&queue->mutex, NULL);
    pthread_cond_init(&queue->cond_full, NULL);
    pthread_cond_init(&queue->cond_empty, NULL);
}

Jt_Car::Jt_Car(pj_uint32_t id):_id(id)
{
	PJ_LOG(3, ("car.cpp", "build a car"));
	_pool = pj_pool_create(&g_cp.factory, "car", INIT_POOL_CAR_SIZE, INC_POOL_CAR_SIZE, NULL);
	
	_event_track = (jt_e_track_node*)PJ_POOL_ZALLOC_T(_pool, jt_e_track_node);
	pj_list_init(_event_track);
	
	_station_track = (jt_s_track_node*)PJ_POOL_ZALLOC_T(_pool, jt_s_track_node);
	pj_list_init(_station_track);
	_station_track->station = NULL;
	_data = pj_pool_zalloc(_pool, MAX_CAR_DATA_LEN);
}

/**
 * This method is to parse and add the choice type 
 * argument values to command structure.
 **/
static pj_status_t add_choice_node(pj_cli_t *cli,
				   pj_xml_node *xml_node,
				   pj_cli_arg_spec *arg,
				   pj_cli_get_dyn_choice get_choice)
{
    pj_xml_node *choice_node;
    pj_xml_node *sub_node;
    pj_cli_arg_choice_val choice_values[PJ_CLI_MAX_CHOICE_VAL];
    pj_status_t status = PJ_SUCCESS;

    sub_node = xml_node;
    arg->type = PJ_CLI_ARG_CHOICE;
    arg->get_dyn_choice = get_choice;						

    choice_node = sub_node->node_head.next;
    while (choice_node != (pj_xml_node*)&sub_node->node_head) {
	pj_xml_attr *choice_attr;
	unsigned *stat_cnt = &arg->stat_choice_cnt;
	pj_cli_arg_choice_val *choice_val = &choice_values[*stat_cnt];		     
	pj_bzero(choice_val, sizeof(*choice_val));

	choice_attr = choice_node->attr_head.next;
	while (choice_attr != &choice_node->attr_head) {
	    if (!pj_stricmp2(&choice_attr->name, "value")) {
		pj_strassign(&choice_val->value, &choice_attr->value);
	    } else if (!pj_stricmp2(&choice_attr->name, "desc")) {
		pj_strassign(&choice_val->desc, &choice_attr->value);
	    }
	    choice_attr = choice_attr->next;
	}		
	if (++(*stat_cnt) >= PJ_CLI_MAX_CHOICE_VAL)
	    break;
	choice_node = choice_node->next;
    }    
    if (arg->stat_choice_cnt > 0) {
        unsigned i;

	arg->stat_choice_val = (pj_cli_arg_choice_val *)
				pj_pool_zalloc(cli->pool, 
					       arg->stat_choice_cnt *
					       sizeof(pj_cli_arg_choice_val));

        for (i = 0; i < arg->stat_choice_cnt; i++) {
	    pj_strdup(cli->pool, &arg->stat_choice_val[i].value, 
		      &choice_values[i].value);
            pj_strdup(cli->pool, &arg->stat_choice_val[i].desc, 
		      &choice_values[i].desc);            
        }
    }
    return status;
}

static void* plc_replay_create(pj_pool_t *pool, unsigned clock_rate, 
			       unsigned samples_per_frame)
{
    struct replay_plc *o;

    PJ_UNUSED_ARG(clock_rate);

    o = pj_pool_alloc(pool, sizeof(struct replay_plc));
    o->size = samples_per_frame * 2;
    o->replay_cnt = 0;
    o->frame = pj_pool_zalloc(pool, o->size);

    return o;
}

pjmedia_sdp_session_clone( pj_pool_t *pool,
			   const pjmedia_sdp_session *rhs)
{
    pjmedia_sdp_session *sess;
    unsigned i;

    PJ_ASSERT_RETURN(pool && rhs, NULL);

    sess = pj_pool_zalloc(pool, sizeof(pjmedia_sdp_session));
    PJ_ASSERT_RETURN(sess != NULL, NULL);

    /* Clone origin line. */
    pj_strdup(pool, &sess->origin.user, &rhs->origin.user);
    sess->origin.id = rhs->origin.id;
    sess->origin.version = rhs->origin.version;
    pj_strdup(pool, &sess->origin.net_type, &rhs->origin.net_type);
    pj_strdup(pool, &sess->origin.addr_type, &rhs->origin.addr_type);
    pj_strdup(pool, &sess->origin.addr, &rhs->origin.addr);

    /* Clone subject line. */
    pj_strdup(pool, &sess->name, &rhs->name);

    /* Clone connection line */
    if (rhs->conn) {
	sess->conn = pjmedia_sdp_conn_clone(pool, rhs->conn);
	PJ_ASSERT_RETURN(sess->conn != NULL, NULL);
    }

    /* Clone time line. */
    sess->time.start = rhs->time.start;
    sess->time.stop = rhs->time.stop;

    /* Duplicate session attributes. */
    sess->attr_count = rhs->attr_count;
    for (i=0; i<rhs->attr_count; ++i) {
	sess->attr[i] = pjmedia_sdp_attr_clone(pool, rhs->attr[i]);
    }

    /* Duplicate media descriptors. */
    sess->media_count = rhs->media_count;
    for (i=0; i<rhs->media_count; ++i) {
	sess->media[i] = pjmedia_sdp_media_clone(pool, rhs->media[i]);
    }

    return sess;
}