SPAN_DECLARE(void) fax_modems_start_slow_modem(fax_modems_state_t *s, int which)
{
switch (which)
{
case FAX_MODEM_V21_RX:
fsk_rx_init(&s->v21_rx, &preset_fsk_specs[FSK_V21CH2], FSK_FRAME_MODE_SYNC, (put_bit_func_t) hdlc_rx_put_bit, &s->hdlc_rx);
fax_modems_set_rx_handler(s, (span_rx_handler_t) &fsk_rx, &s->v21_rx, (span_rx_fillin_handler_t) &fsk_rx_fillin, &s->v21_rx);
fsk_rx_signal_cutoff(&s->v21_rx, -39.09f);
s->rx_frame_received = false;
break;
case FAX_MODEM_CED_TONE_RX:
modem_connect_tones_rx_init(&s->connect_rx, MODEM_CONNECT_TONES_FAX_CED, s->tone_callback, s->tone_callback_user_data);
fax_modems_set_rx_handler(s, (span_rx_handler_t) &modem_connect_tones_rx, &s->connect_rx, (span_rx_fillin_handler_t) &modem_connect_tones_rx_fillin, &s->connect_rx);
break;
case FAX_MODEM_CNG_TONE_RX:
modem_connect_tones_rx_init(&s->connect_rx, MODEM_CONNECT_TONES_FAX_CNG, s->tone_callback, s->tone_callback_user_data);
fax_modems_set_rx_handler(s, (span_rx_handler_t) &modem_connect_tones_rx, &s->connect_rx, (span_rx_fillin_handler_t) &modem_connect_tones_rx_fillin, &s->connect_rx);
break;
case FAX_MODEM_V21_TX:
fsk_tx_init(&s->v21_tx, &preset_fsk_specs[FSK_V21CH2], (get_bit_func_t) hdlc_tx_get_bit, &s->hdlc_tx);
fax_modems_set_tx_handler(s, (span_tx_handler_t) &fsk_tx, &s->v21_tx);
fax_modems_set_next_tx_handler(s, (span_tx_handler_t) NULL, NULL);
break;
case FAX_MODEM_CED_TONE_TX:
modem_connect_tones_tx_init(&s->connect_tx, MODEM_CONNECT_TONES_FAX_CED);
fax_modems_set_tx_handler(s, (span_tx_handler_t) &modem_connect_tones_tx, &s->connect_tx);
fax_modems_set_next_tx_handler(s, (span_tx_handler_t) NULL, NULL);
break;
case FAX_MODEM_CNG_TONE_TX:
modem_connect_tones_tx_init(&s->connect_tx, MODEM_CONNECT_TONES_FAX_CNG);
fax_modems_set_tx_handler(s, (span_tx_handler_t) &modem_connect_tones_tx, &s->connect_tx);
fax_modems_set_next_tx_handler(s, (span_tx_handler_t) NULL, NULL);
break;
}
}
static int set_next_tx_type(fax_state_t *s)
{
fax_modems_state_t *t;
t = &s->modems;
if (t->next_tx_handler)
{
fax_modems_set_tx_handler(s, t->next_tx_handler, t->next_tx_user_data);
t->next_tx_handler = NULL;
return 0;
}
/* If there is nothing else to change to, so use zero length silence */
silence_gen_alter(&t->silence_gen, 0);
fax_modems_set_tx_handler(s, (span_tx_handler_t *) &silence_gen, &t->silence_gen);
fax_modems_set_next_tx_handler(s, (span_tx_handler_t *) NULL, NULL);
t->transmit = FALSE;
return -1;
}
static void fax_set_tx_type(void *user_data, int type, int bit_rate, int short_train, int use_hdlc)
{
fax_state_t *s;
fax_modems_state_t *t;
int tone;
s = (fax_state_t *) user_data;
t = &s->modems;
span_log(&s->logging, SPAN_LOG_FLOW, "Set tx type %d\n", type);
if (t->current_tx_type == type)
return;
switch (type)
{
case T30_MODEM_PAUSE:
silence_gen_alter(&t->silence_gen, ms_to_samples(short_train));
fax_modems_set_tx_handler(t, (span_tx_handler_t) &silence_gen, &t->silence_gen);
fax_modems_set_next_tx_handler(t, (span_tx_handler_t) NULL, NULL);
t->transmit = true;
break;
case T30_MODEM_CED:
case T30_MODEM_CNG:
tone = (type == T30_MODEM_CED) ? FAX_MODEM_CED_TONE_TX : FAX_MODEM_CNG_TONE_TX;
fax_modems_start_slow_modem(t, tone);
fax_modems_set_next_tx_handler(t, (span_tx_handler_t) NULL, NULL);
t->transmit = true;
break;
case T30_MODEM_V21:
fax_modems_start_slow_modem(t, FAX_MODEM_V21_TX);
/* The spec says 1s +-15% of preamble. So, the minimum is 32 octets. */
fax_modems_hdlc_tx_flags(t, 32);
/* Pause before switching from phase C, as per T.30 5.3.2.2. If we omit this, the receiver
might not see the carrier fall between the high speed and low speed sections. In practice,
a 75ms gap before any V.21 transmission is harmless, adds little to the overall length of
a call, and ensures the receiving end is ready. */
silence_gen_alter(&t->silence_gen, ms_to_samples(75));
fax_modems_set_tx_handler(t, (span_tx_handler_t) &silence_gen, &t->silence_gen);
fax_modems_set_next_tx_handler(t, (span_tx_handler_t) &fsk_tx, &t->v21_tx);
t->transmit = true;
break;
case T30_MODEM_V17:
silence_gen_alter(&t->silence_gen, ms_to_samples(75));
/* For any fast modem, set 200ms of preamble flags */
fax_modems_hdlc_tx_flags(t, bit_rate/(8*5));
fax_modems_start_fast_modem(t, FAX_MODEM_V17_TX, bit_rate, short_train, use_hdlc);
fax_modems_set_tx_handler(t, (span_tx_handler_t) &silence_gen, &t->silence_gen);
fax_modems_set_next_tx_handler(t, (span_tx_handler_t) &v17_tx, &t->fast_modems.v17_tx);
t->transmit = true;
break;
case T30_MODEM_V27TER:
silence_gen_alter(&t->silence_gen, ms_to_samples(75));
/* For any fast modem, set 200ms of preamble flags */
fax_modems_hdlc_tx_flags(t, bit_rate/(8*5));
fax_modems_start_fast_modem(t, FAX_MODEM_V27TER_TX, bit_rate, short_train, use_hdlc);
fax_modems_set_tx_handler(t, (span_tx_handler_t) &silence_gen, &t->silence_gen);
fax_modems_set_next_tx_handler(t, (span_tx_handler_t) &v27ter_tx, &t->fast_modems.v27ter_tx);
t->transmit = true;
break;
case T30_MODEM_V29:
silence_gen_alter(&t->silence_gen, ms_to_samples(75));
/* For any fast modem, set 200ms of preamble flags */
fax_modems_hdlc_tx_flags(t, bit_rate/(8*5));
fax_modems_start_fast_modem(t, FAX_MODEM_V29_TX, bit_rate, short_train, use_hdlc);
fax_modems_set_tx_handler(t, (span_tx_handler_t) &silence_gen, &t->silence_gen);
fax_modems_set_next_tx_handler(t, (span_tx_handler_t) &v29_tx, &t->fast_modems.v29_tx);
t->transmit = true;
break;
case T30_MODEM_DONE:
span_log(&s->logging, SPAN_LOG_FLOW, "FAX exchange complete\n");
/* Fall through */
default:
silence_gen_alter(&t->silence_gen, 0);
fax_modems_set_tx_handler(t, (span_tx_handler_t) &silence_gen, &t->silence_gen);
fax_modems_set_next_tx_handler(t, (span_tx_handler_t) NULL, NULL);
t->transmit = false;
break;
}
t->tx_bit_rate = bit_rate;
t->current_tx_type = type;
}
SPAN_DECLARE(void) fax_modems_start_fast_modem(fax_modems_state_t *s, int which, int bit_rate, int short_train, int hdlc_mode)
{
put_bit_func_t put_bit;
get_bit_func_t get_bit;
void *get_bit_user_data;
void *put_bit_user_data;
s->bit_rate = bit_rate;
if (hdlc_mode)
{
get_bit = (get_bit_func_t) hdlc_tx_get_bit;
get_bit_user_data = (void *) &s->hdlc_tx;
put_bit = (put_bit_func_t) hdlc_rx_put_bit;
put_bit_user_data = (void *) &s->hdlc_rx;
}
else
{
get_bit = s->get_bit;
get_bit_user_data = s->get_bit_user_data;
put_bit = s->put_bit;
put_bit_user_data = s->put_bit_user_data;
}
/*endif*/
/* If we change modems we need to do a complete reinitialisation of the modem, because
the modems use overlapping memory. */
if (s->fast_modem != which)
{
s->current_rx_type = which;
s->short_train = false;
s->fast_modem = which;
if (hdlc_mode)
s->rx_frame_received = false;
switch (s->fast_modem)
{
case FAX_MODEM_V27TER_RX:
v27ter_rx_init(&s->fast_modems.v27ter_rx, s->bit_rate, put_bit, put_bit_user_data);
v27ter_rx_set_modem_status_handler(&s->fast_modems.v27ter_rx, v27ter_rx_status_handler, s);
fax_modems_set_rx_handler(s, (span_rx_handler_t) &fax_modems_v27ter_v21_rx, s, (span_rx_fillin_handler_t) &fax_modems_v27ter_v21_rx_fillin, s);
break;
case FAX_MODEM_V29_RX:
v29_rx_init(&s->fast_modems.v29_rx, s->bit_rate, put_bit, put_bit_user_data);
v29_rx_signal_cutoff(&s->fast_modems.v29_rx, -45.5f);
v29_rx_set_modem_status_handler(&s->fast_modems.v29_rx, v29_rx_status_handler, s);
fax_modems_set_rx_handler(s, (span_rx_handler_t) &fax_modems_v29_v21_rx, s, (span_rx_fillin_handler_t) &fax_modems_v29_v21_rx_fillin, s);
break;
case FAX_MODEM_V17_RX:
v17_rx_init(&s->fast_modems.v17_rx, s->bit_rate, put_bit, put_bit_user_data);
v17_rx_set_modem_status_handler(&s->fast_modems.v17_rx, v17_rx_status_handler, s);
fax_modems_set_rx_handler(s, (span_rx_handler_t) &fax_modems_v17_v21_rx, s, (span_rx_fillin_handler_t) &fax_modems_v17_v21_rx_fillin, s);
break;
case FAX_MODEM_V27TER_TX:
v27ter_tx_init(&s->fast_modems.v27ter_tx, s->bit_rate, s->use_tep, get_bit, get_bit_user_data);
fax_modems_set_tx_handler(s, (span_tx_handler_t) &v27ter_tx, &s->fast_modems.v27ter_tx);
fax_modems_set_next_tx_handler(s, (span_tx_handler_t) NULL, NULL);
break;
case FAX_MODEM_V29_TX:
v29_tx_init(&s->fast_modems.v29_tx, s->bit_rate, s->use_tep, get_bit, get_bit_user_data);
fax_modems_set_tx_handler(s, (span_tx_handler_t) &v29_tx, &s->fast_modems.v29_tx);
fax_modems_set_next_tx_handler(s, (span_tx_handler_t) NULL, NULL);
break;
case FAX_MODEM_V17_TX:
v17_tx_init(&s->fast_modems.v17_tx, s->bit_rate, s->use_tep, get_bit, get_bit_user_data);
fax_modems_set_tx_handler(s, (span_tx_handler_t) &v17_tx, &s->fast_modems.v17_tx);
fax_modems_set_next_tx_handler(s, (span_tx_handler_t) NULL, NULL);
break;
}
/*endswitch*/
}
else
{
s->short_train = short_train;
switch (s->fast_modem)
{
case FAX_MODEM_V27TER_RX:
v27ter_rx_restart(&s->fast_modems.v27ter_rx, s->bit_rate, false);
v27ter_rx_set_put_bit(&s->fast_modems.v27ter_rx, put_bit, put_bit_user_data);
v27ter_rx_set_modem_status_handler(&s->fast_modems.v27ter_rx, v27ter_rx_status_handler, s);
fax_modems_set_rx_handler(s, (span_rx_handler_t) &fax_modems_v27ter_v21_rx, s, (span_rx_fillin_handler_t) &fax_modems_v27ter_v21_rx_fillin, s);
break;
case FAX_MODEM_V29_RX:
v29_rx_restart(&s->fast_modems.v29_rx, s->bit_rate, false);
v29_rx_set_put_bit(&s->fast_modems.v29_rx, put_bit, put_bit_user_data);
v29_rx_set_modem_status_handler(&s->fast_modems.v29_rx, v29_rx_status_handler, s);
fax_modems_set_rx_handler(s, (span_rx_handler_t) &fax_modems_v29_v21_rx, s, (span_rx_fillin_handler_t) &fax_modems_v29_v21_rx_fillin, s);
break;
case FAX_MODEM_V17_RX:
v17_rx_restart(&s->fast_modems.v17_rx, s->bit_rate, s->short_train);
v17_rx_set_put_bit(&s->fast_modems.v17_rx, put_bit, put_bit_user_data);
v17_rx_set_modem_status_handler(&s->fast_modems.v17_rx, v17_rx_status_handler, s);
fax_modems_set_rx_handler(s, (span_rx_handler_t) &fax_modems_v17_v21_rx, s, (span_rx_fillin_handler_t) &fax_modems_v17_v21_rx_fillin, s);
break;
case FAX_MODEM_V27TER_TX:
v27ter_tx_restart(&s->fast_modems.v27ter_tx, s->bit_rate, s->use_tep);
v27ter_tx_set_get_bit(&s->fast_modems.v27ter_tx, get_bit, get_bit_user_data);
fax_modems_set_tx_handler(s, (span_tx_handler_t) &v27ter_tx, &s->fast_modems.v27ter_tx);
fax_modems_set_next_tx_handler(s, (span_tx_handler_t) NULL, NULL);
break;
case FAX_MODEM_V29_TX:
v29_tx_restart(&s->fast_modems.v29_tx, s->bit_rate, s->use_tep);
v29_tx_set_get_bit(&s->fast_modems.v29_tx, get_bit, get_bit_user_data);
fax_modems_set_tx_handler(s, (span_tx_handler_t) &v29_tx, &s->fast_modems.v29_tx);
fax_modems_set_next_tx_handler(s, (span_tx_handler_t) NULL, NULL);
break;
case FAX_MODEM_V17_TX:
v17_tx_restart(&s->fast_modems.v17_tx, s->bit_rate, s->use_tep, s->short_train);
v17_tx_set_get_bit(&s->fast_modems.v17_tx, get_bit, get_bit_user_data);
fax_modems_set_tx_handler(s, (span_tx_handler_t) &v17_tx, &s->fast_modems.v17_tx);
fax_modems_set_next_tx_handler(s, (span_tx_handler_t) NULL, NULL);
break;
}
/*endswitch*/
}
/*endif*/
}
static void fax_set_tx_type(void *user_data, int type, int bit_rate, int short_train, int use_hdlc)
{
fax_state_t *s;
get_bit_func_t get_bit_func;
void *get_bit_user_data;
fax_modems_state_t *t;
int tone;
s = (fax_state_t *) user_data;
t = &s->modems;
span_log(&s->logging, SPAN_LOG_FLOW, "Set tx type %d\n", type);
if (t->current_tx_type == type)
return;
/*endif*/
if (use_hdlc)
{
get_bit_func = (get_bit_func_t) hdlc_tx_get_bit;
get_bit_user_data = (void *) &t->hdlc_tx;
}
else
{
get_bit_func = t30_non_ecm_get_bit;
get_bit_user_data = (void *) &s->t30;
}
/*endif*/
switch (type)
{
case T30_MODEM_PAUSE:
silence_gen_alter(&t->silence_gen, ms_to_samples(short_train));
fax_modems_set_tx_handler(s, (span_tx_handler_t *) &silence_gen, &t->silence_gen);
fax_modems_set_next_tx_handler(s, (span_tx_handler_t *) NULL, NULL);
t->transmit = true;
break;
case T30_MODEM_CED:
case T30_MODEM_CNG:
if (type == T30_MODEM_CED)
tone = MODEM_CONNECT_TONES_FAX_CED;
else
tone = MODEM_CONNECT_TONES_FAX_CNG;
/*endif*/
modem_connect_tones_tx_init(&t->connect_tx, tone);
fax_modems_set_tx_handler(s, (span_tx_handler_t *) &modem_connect_tones_tx, &t->connect_tx);
fax_modems_set_next_tx_handler(s, (span_tx_handler_t *) NULL, NULL);
t->transmit = true;
break;
case T30_MODEM_V21:
fsk_tx_init(&t->v21_tx, &preset_fsk_specs[FSK_V21CH2], get_bit_func, get_bit_user_data);
/* The spec says 1s +-15% of preamble. So, the minimum is 32 octets. */
hdlc_tx_flags(&t->hdlc_tx, 32);
/* Pause before switching from phase C, as per T.30 5.3.2.2. If we omit this, the receiver
might not see the carrier fall between the high speed and low speed sections. In practice,
a 75ms gap before any V.21 transmission is harmless, adds little to the overall length of
a call, and ensures the receiving end is ready. */
silence_gen_alter(&t->silence_gen, ms_to_samples(75));
fax_modems_set_tx_handler(s, (span_tx_handler_t *) &silence_gen, &t->silence_gen);
fax_modems_set_next_tx_handler(s, (span_tx_handler_t *) &fsk_tx, &t->v21_tx);
t->transmit = true;
break;
case T30_MODEM_V17:
silence_gen_alter(&t->silence_gen, ms_to_samples(75));
/* For any fast modem, set 200ms of preamble flags */
hdlc_tx_flags(&t->hdlc_tx, bit_rate/(8*5));
v17_tx_restart(&t->fast_modems.v17_tx, bit_rate, t->use_tep, short_train);
v17_tx_set_get_bit(&t->fast_modems.v17_tx, get_bit_func, get_bit_user_data);
fax_modems_set_tx_handler(s, (span_tx_handler_t *) &silence_gen, &t->silence_gen);
fax_modems_set_next_tx_handler(s, (span_tx_handler_t *) &v17_tx, &t->fast_modems.v17_tx);
t->transmit = true;
break;
case T30_MODEM_V27TER:
silence_gen_alter(&t->silence_gen, ms_to_samples(75));
/* For any fast modem, set 200ms of preamble flags */
hdlc_tx_flags(&t->hdlc_tx, bit_rate/(8*5));
v27ter_tx_restart(&t->fast_modems.v27ter_tx, bit_rate, t->use_tep);
v27ter_tx_set_get_bit(&t->fast_modems.v27ter_tx, get_bit_func, get_bit_user_data);
fax_modems_set_tx_handler(s, (span_tx_handler_t *) &silence_gen, &t->silence_gen);
fax_modems_set_next_tx_handler(s, (span_tx_handler_t *) &v27ter_tx, &t->fast_modems.v27ter_tx);
t->transmit = true;
break;
case T30_MODEM_V29:
silence_gen_alter(&t->silence_gen, ms_to_samples(75));
/* For any fast modem, set 200ms of preamble flags */
hdlc_tx_flags(&t->hdlc_tx, bit_rate/(8*5));
v29_tx_restart(&t->fast_modems.v29_tx, bit_rate, t->use_tep);
v29_tx_set_get_bit(&t->fast_modems.v29_tx, get_bit_func, get_bit_user_data);
fax_modems_set_tx_handler(s, (span_tx_handler_t *) &silence_gen, &t->silence_gen);
fax_modems_set_next_tx_handler(s, (span_tx_handler_t *) &v29_tx, &t->fast_modems.v29_tx);
t->transmit = true;
break;
case T30_MODEM_DONE:
span_log(&s->logging, SPAN_LOG_FLOW, "FAX exchange complete\n");
/* Fall through */
default:
silence_gen_alter(&t->silence_gen, 0);
fax_modems_set_tx_handler(s, (span_tx_handler_t *) &silence_gen, &t->silence_gen);
fax_modems_set_next_tx_handler(s, (span_tx_handler_t *) NULL, NULL);
t->transmit = false;
break;
}
/*endswitch*/
t->tx_bit_rate = bit_rate;
t->current_tx_type = type;
}
