static int t30_tests(int t38_mode, int use_ecm, int use_gui, int log_audio, int test_sending, int g1050_model_no, int g1050_speed_pattern_no)
{
    t38_terminal_state_t *t38_state;
    fax_state_t *fax_state;
    uint8_t msg[1024];
    char buf[1024];
    int len;
    int msg_len;
    int t30_len;
    int t31_len;
    int t38_version;
    int without_pacing;
    int use_tep;
    int seq_no;
    double tx_when;
    double rx_when;
    t30_state_t *t30;
    t38_core_state_t *t38_core;
    logging_state_t *logging;
    int k;
    int outframes;
    int ret;
    int16_t t30_amp[SAMPLES_PER_CHUNK];
    int16_t t31_amp[SAMPLES_PER_CHUNK];
    int16_t silence[SAMPLES_PER_CHUNK];
    int16_t out_amp[2*SAMPLES_PER_CHUNK];
    SNDFILE *wave_handle;
    SNDFILE *in_handle;
    at_state_t *at_state;
#if defined(WIN32)
	DWORD read_bytes;
	OVERLAPPED o;
#endif

    /* Test the T.31 modem against the full FAX machine in spandsp */
    
    /* Set up the test environment */
    t38_version = 1;
    without_pacing = FALSE;
    use_tep = FALSE;

    wave_handle = NULL;
    if (log_audio)
    {
        if ((wave_handle = sf_open_telephony_write(OUTPUT_WAVE_FILE_NAME, 2)) == NULL)
        {
            fprintf(stderr, "    Cannot create audio file '%s'\n", OUTPUT_WAVE_FILE_NAME);
            exit(2);
        }
    }

    in_handle = NULL;
    if (decode_test_file)
    {
        if ((in_handle = sf_open_telephony_read(decode_test_file, 1)) == NULL)
        {
            fprintf(stderr, "    Cannot create audio file '%s'\n", decode_test_file);
            exit(2);
        }
    }

    srand48(0x1234567);
    if ((path_a_to_b = g1050_init(g1050_model_no, g1050_speed_pattern_no, 100, 33)) == NULL)
    {
        fprintf(stderr, "Failed to start IP network path model\n");
        exit(2);
    }
    if ((path_b_to_a = g1050_init(g1050_model_no, g1050_speed_pattern_no, 100, 33)) == NULL)
    {
        fprintf(stderr, "Failed to start IP network path model\n");
        exit(2);
    }

    t38_state = NULL;
    fax_state = NULL;
    if (test_sending)
    {
        if (t38_mode)
        {
            if ((t38_state = t38_terminal_init(NULL, FALSE, t38_tx_packet_handler, t31_state)) == NULL)
            {
                fprintf(stderr, "Cannot start the T.38 channel\n");
                exit(2);
            }
            t30 = t38_terminal_get_t30_state(t38_state);
        }
        else
        {
            fax_state = fax_init(NULL, FALSE);
            t30 = fax_get_t30_state(fax_state);
        }
        t30_set_rx_file(t30, OUTPUT_FILE_NAME, -1);
        countdown = 0;
    }
    else
    {
        if (t38_mode)
        {
            if ((t38_state = t38_terminal_init(NULL, TRUE, t38_tx_packet_handler, t31_state)) == NULL)
            {
                fprintf(stderr, "Cannot start the T.38 channel\n");
                exit(2);
            }
            t30 = t38_terminal_get_t30_state(t38_state);
        }
        else
        {
            fax_state = fax_init(NULL, TRUE);
            t30 = fax_get_t30_state(fax_state);
        }
        t30_set_tx_file(t30, INPUT_FILE_NAME, -1, -1);
        countdown = 250;
    }

    t30_set_ecm_capability(t30, use_ecm);

    if (t38_mode)
    {
        t38_core = t38_terminal_get_t38_core_state(t38_state);
        t38_set_t38_version(t38_core, t38_version);
        t38_terminal_set_config(t38_state, without_pacing);
        t38_terminal_set_tep_mode(t38_state, use_tep);
    }

    t30_set_tx_ident(t30, "11111111");
    t30_set_supported_modems(t30, T30_SUPPORT_V27TER | T30_SUPPORT_V29 | T30_SUPPORT_V17);
    //t30_set_tx_nsf(t30, (const uint8_t *) "\x50\x00\x00\x00Spandsp\x00", 12);
    t30_set_phase_b_handler(t30, phase_b_handler, (void *) 'A');
    t30_set_phase_d_handler(t30, phase_d_handler, (void *) 'A');
    t30_set_phase_e_handler(t30, phase_e_handler, (void *) 'A');

    if (t38_mode)
        logging = t38_terminal_get_logging_state(t38_state);
    else
        logging = t30_get_logging_state(t30);
    span_log_set_level(logging, SPAN_LOG_DEBUG | SPAN_LOG_SHOW_TAG | SPAN_LOG_SHOW_SAMPLE_TIME);
    span_log_set_tag(logging, (t38_mode)  ?  "T.38"  :  "FAX");

    if (t38_mode)
    {
        t38_core = t38_terminal_get_t38_core_state(t38_state);
        logging = t38_core_get_logging_state(t38_core);
        span_log_set_level(logging, SPAN_LOG_DEBUG | SPAN_LOG_SHOW_TAG | SPAN_LOG_SHOW_SAMPLE_TIME);
        span_log_set_tag(logging, "T.38");

        logging = t30_get_logging_state(t30);
        span_log_set_level(logging, SPAN_LOG_DEBUG | SPAN_LOG_SHOW_TAG | SPAN_LOG_SHOW_SAMPLE_TIME);
        span_log_set_tag(logging, "T.38");
    }
    else
    {
        logging = fax_get_logging_state(fax_state);
        span_log_set_level(logging, SPAN_LOG_DEBUG | SPAN_LOG_SHOW_TAG | SPAN_LOG_SHOW_SAMPLE_TIME);
        span_log_set_tag(logging, "FAX");
    }

    memset(silence, 0, sizeof(silence));
    memset(t30_amp, 0, sizeof(t30_amp));

    /* Now set up and run the T.31 modem */
    if ((t31_state = t31_init(NULL, at_tx_handler, &modem[0], t31_call_control, &modem[0], t31_tx_packet_handler, NULL)) == NULL)
    {
        fprintf(stderr, "    Cannot start the T.31 modem\n");
        exit(2);
    }
    at_state = t31_get_at_state(t31_state);

    logging = t31_get_logging_state(t31_state);
    span_log_set_level(logging, SPAN_LOG_DEBUG | SPAN_LOG_SHOW_TAG | SPAN_LOG_SHOW_SAMPLE_TIME);
    span_log_set_tag(logging, "T.31");

    logging = at_get_logging_state(at_state);
    span_log_set_level(logging, SPAN_LOG_DEBUG | SPAN_LOG_SHOW_TAG | SPAN_LOG_SHOW_SAMPLE_TIME);
    span_log_set_tag(logging, "T.31");

    if (t38_mode)
    {
        t38_core = t31_get_t38_core_state(t31_state);
        logging = t38_core_get_logging_state(t38_core);
        span_log_set_level(logging, SPAN_LOG_DEBUG | SPAN_LOG_SHOW_TAG | SPAN_LOG_SHOW_SAMPLE_TIME);
        span_log_set_tag(logging, "T.31");

        t31_set_mode(t31_state, TRUE);
        t38_set_t38_version(t38_core, t38_version);
    }

    at_reset_call_info(at_state);
    at_set_call_info(at_state, "DATE", "1231");
    at_set_call_info(at_state, "TIME", "1200");
    at_set_call_info(at_state, "NAME", "Name");
    at_set_call_info(at_state, "NMBR", "123456789");
    at_set_call_info(at_state, "ANID", "987654321");
    at_set_call_info(at_state, "USER", "User");
    at_set_call_info(at_state, "CDID", "234567890");
    at_set_call_info(at_state, "NDID", "345678901");

#if defined(ENABLE_GUI)
    if (use_gui)
        start_media_monitor();
#endif

    while (!done)
    {
        /* Deal with call setup, through the AT interface. */ 
        if (test_sending)
        {
        }
        else
        {
            if (answered == 0)
            {
                if (--countdown == 0)
                {
                    t31_call_event(t31_state, AT_CALL_EVENT_ALERTING);
                    countdown = 250;
                }
            }
            else if (answered == 1)
            {
printf("ZZZ\n");
                answered = 2;
                t31_call_event(t31_state, AT_CALL_EVENT_ANSWERED);
            }
        }

        ret = modem_wait_sock(modem[0].master, 20, MODEM_POLL_READ);
        if ((ret & MODEM_POLL_READ))
        {
#if defined(WIN32)
			o.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);

			/* Initialize the rest of the OVERLAPPED structure to zero. */
			o.Internal = 0;
			o.InternalHigh = 0;
			o.Offset = 0;
			o.OffsetHigh = 0;
			assert(o.hEvent);
			if (!ReadFile(modem->master, buf, avail, &read_bytes, &o))
				GetOverlappedResult(modem->master, &o, &read_bytes, TRUE);
			CloseHandle (o.hEvent);
			if ((len = read_bytes))
#else
            if ((len = read(modem[0].master, buf, 1024)))
#endif
{
int i;

printf("YYY %d - ", len);
for (i = 0;  i < len;  i++)
    printf(" 0x%02x", buf[i] & 0xFF);
printf("\n");
                t31_at_rx(t31_state, buf, len);
}
        }

        if (answered == 2)
        {
            if (t38_mode)
            {
                while ((msg_len = g1050_get(path_a_to_b, msg, 1024, when, &seq_no, &tx_when, &rx_when)) >= 0)
                {
#if defined(ENABLE_GUI)
                    if (use_gui)
                        media_monitor_rx(seq_no, tx_when, rx_when);
#endif
                    t38_core = t31_get_t38_core_state(t31_state);
                    t38_core_rx_ifp_packet(t38_core, msg, msg_len, seq_no);
                }
                while ((msg_len = g1050_get(path_b_to_a, msg, 1024, when, &seq_no, &tx_when, &rx_when)) >= 0)
                {
#if defined(ENABLE_GUI)
                    if (use_gui)
                        media_monitor_rx(seq_no, tx_when, rx_when);
#endif
                    t38_core = t38_terminal_get_t38_core_state(t38_state);
                    t38_core_rx_ifp_packet(t38_core, msg, msg_len, seq_no);
                }
#if defined(ENABLE_GUI)
                if (use_gui)
                    media_monitor_update_display();
#endif
                /* Bump the G.1050 models along */
                when += (float) SAMPLES_PER_CHUNK/(float) SAMPLE_RATE;

                /* Bump things along on the t38_terminal side */
                span_log_bump_samples(t38_terminal_get_logging_state(t38_state), SAMPLES_PER_CHUNK);
                t38_core = t38_terminal_get_t38_core_state(t38_state);
                span_log_bump_samples(t38_core_get_logging_state(t38_core), SAMPLES_PER_CHUNK);

                t38_terminal_send_timeout(t38_state, SAMPLES_PER_CHUNK);
                t31_t38_send_timeout(t31_state, SAMPLES_PER_CHUNK);
            }
            else
            {
                t30_len = fax_tx(fax_state, t30_amp, SAMPLES_PER_CHUNK);
                /* The receive side always expects a full block of samples, but the
                   transmit side may not be sending any when it doesn't need to. We
                   may need to pad with some silence. */
                if (t30_len < SAMPLES_PER_CHUNK)
                {
                    memset(t30_amp + t30_len, 0, sizeof(int16_t)*(SAMPLES_PER_CHUNK - t30_len));
                    t30_len = SAMPLES_PER_CHUNK;
                }
                if (log_audio)
                {
                    for (k = 0;  k < t30_len;  k++)
                        out_amp[2*k] = t30_amp[k];
                }
                if (t31_rx(t31_state, t30_amp, t30_len))
                    break;
                t31_len = t31_tx(t31_state, t31_amp, SAMPLES_PER_CHUNK);
                if (t31_len < SAMPLES_PER_CHUNK)
                {
                    memset(t31_amp + t31_len, 0, sizeof(int16_t)*(SAMPLES_PER_CHUNK - t31_len));
                    t31_len = SAMPLES_PER_CHUNK;
                }
                if (log_audio)
                {
                    for (k = 0;  k < t31_len;  k++)
                        out_amp[2*k + 1] = t31_amp[k];
                }
                if (fax_rx(fax_state, t31_amp, SAMPLES_PER_CHUNK))
                    break;

                if (log_audio)
                {
                    outframes = sf_writef_short(wave_handle, out_amp, SAMPLES_PER_CHUNK);
                    if (outframes != SAMPLES_PER_CHUNK)
                        break;
                }

                /* Bump things along on the FAX machine side */
                span_log_bump_samples(fax_get_logging_state(fax_state), SAMPLES_PER_CHUNK);
            }
            /* Bump things along on the FAX machine side */
            span_log_bump_samples(t30_get_logging_state(t30), SAMPLES_PER_CHUNK);

            /* Bump things along on the T.31 modem side */
            t38_core = t31_get_t38_core_state(t31_state);
            span_log_bump_samples(t38_core_get_logging_state(t38_core), SAMPLES_PER_CHUNK);
            span_log_bump_samples(t31_get_logging_state(t31_state), SAMPLES_PER_CHUNK);
            span_log_bump_samples(at_get_logging_state(t31_get_at_state(t31_state)), SAMPLES_PER_CHUNK);
        }
    }

    if (t38_mode)
        t38_terminal_release(t38_state);

    if (decode_test_file)
    {
        if (sf_close_telephony(in_handle))
        {
            fprintf(stderr, "    Cannot close audio file '%s'\n", decode_test_file);
            exit(2);
        }
    }
    if (log_audio)
    {
        if (sf_close_telephony(wave_handle))
        {
            fprintf(stderr, "    Cannot close audio file '%s'\n", OUTPUT_WAVE_FILE_NAME);
            exit(2);
        }
    }

    if (!done)
    {
        printf("Tests failed\n");
        return 2;
    }

    return 0;
}
static void *SWITCH_THREAD_FUNC modem_thread(switch_thread_t *thread, void *obj)
{
	modem_t *modem = obj;
	int r, avail;
#ifdef WIN32
	DWORD readBytes;
	OVERLAPPED o;
#endif
	char buf[T31_TX_BUF_LEN], tmp[80];

	switch_mutex_lock(globals.mutex);
	modem_init(modem, control_handler);
	globals.THREADCOUNT++;
	switch_mutex_unlock(globals.mutex);

	if (switch_test_flag(modem, MODEM_FLAG_RUNNING)) {
		switch_mutex_lock(modem->cond_mutex);

		while (switch_test_flag(modem, MODEM_FLAG_RUNNING)) {

#ifndef WIN32
			r = modem_wait_sock(modem->master, -1, MODEM_POLL_READ | MODEM_POLL_ERROR);
#else
			r = modem_wait_sock(modem, -1, MODEM_POLL_READ | MODEM_POLL_ERROR);
#endif

			if (!switch_test_flag(modem, MODEM_FLAG_RUNNING)) {
				break;
			}

			if (r < 0 || !(r & MODEM_POLL_READ) || (r & MODEM_POLL_ERROR)) {
				switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_WARNING, "Bad Read on master [%s] [%d]\n", modem->devlink, r);
				break;
			}

			modem->last_event = switch_time_now();

			if (switch_test_flag(modem, MODEM_FLAG_XOFF)) {
				switch_thread_cond_wait(modem->cond, modem->cond_mutex);
				modem->last_event = switch_time_now();
			}

			avail = sizeof(buf) - modem->t31_state->tx.in_bytes + modem->t31_state->tx.out_bytes - 1;

			if (avail == 0) {
				switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_WARNING, "Buffer Full, retrying....\n");
				switch_yield(10000);
				continue;
			}

#ifndef WIN32		
			r = read(modem->master, buf, avail);
#else
			o.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);

			/* Initialize the rest of the OVERLAPPED structure to zero. */
			o.Internal = 0;
			o.InternalHigh = 0;
			o.Offset = 0;
			o.OffsetHigh = 0;
			assert(o.hEvent);
			if (!ReadFile(modem->master, buf, avail, &readBytes, &o)) {
				GetOverlappedResult(modem->master,&o,&readBytes,TRUE);
			}
			CloseHandle (o.hEvent);
			r = readBytes;
#endif

			t31_at_rx(modem->t31_state, buf, r);

			memset(tmp, 0, sizeof(tmp));
			if (!strncasecmp(buf, "AT", 2)) {
				int x;
				strncpy(tmp, buf, r);
				for(x = 0; x < r; x++) {
					if(tmp[x] == '\r' || tmp[x] == '\n') {
						tmp[x] = '\0';
					}
				}

				switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_DEBUG1,   "Command on %s [%s]\n", modem->devlink, tmp);
			}
		}

		switch_mutex_unlock(modem->cond_mutex);

		if (switch_test_flag(modem, MODEM_FLAG_RUNNING)) {
			modem_close(modem);
		}
	}

	switch_log_printf(SWITCH_CHANNEL_LOG, SWITCH_LOG_INFO,   "Thread ended for %s\n", modem->devlink);

	switch_mutex_lock(globals.mutex);
	globals.THREADCOUNT--;
	switch_mutex_unlock(globals.mutex);

	return NULL;
}