static int set_next_tx_type(fax_state_t *s)
{
if (s->next_tx_handler)
{
s->tx_handler = s->next_tx_handler;
s->tx_user_data = s->next_tx_user_data;
s->next_tx_handler = NULL;
return 0;
}
/* If there is nothing else to change to, so use zero length silence */
silence_gen_alter(&(s->silence_gen), 0);
s->tx_handler = (span_tx_handler_t *) &silence_gen;
s->tx_user_data = &(s->silence_gen);
s->next_tx_handler = NULL;
s->transmit = FALSE;
return -1;
}
static int set_next_tx_type(fax_state_t *s)
{
fax_modems_state_t *t;
t = &s->modems;
if (t->next_tx_handler)
{
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);
set_tx_handler(s, (span_tx_handler_t *) &silence_gen, &t->silence_gen);
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;
}
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;
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;
}
switch (type)
{
case T30_MODEM_PAUSE:
silence_gen_alter(&t->silence_gen, ms_to_samples(short_train));
set_tx_handler(s, (span_tx_handler_t *) &silence_gen, &t->silence_gen);
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;
modem_connect_tones_tx_init(&t->connect_tx, tone);
set_tx_handler(s, (span_tx_handler_t *) &modem_connect_tones_tx, &t->connect_tx);
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));
set_tx_handler(s, (span_tx_handler_t *) &silence_gen, &t->silence_gen);
set_next_tx_handler(s, (span_tx_handler_t *) &fsk_tx, &t->v21_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->v27ter_tx, bit_rate, t->use_tep);
v27ter_tx_set_get_bit(&t->v27ter_tx, get_bit_func, get_bit_user_data);
set_tx_handler(s, (span_tx_handler_t *) &silence_gen, &t->silence_gen);
set_next_tx_handler(s, (span_tx_handler_t *) &v27ter_tx, &t->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->v29_tx, bit_rate, t->use_tep);
v29_tx_set_get_bit(&t->v29_tx, get_bit_func, get_bit_user_data);
set_tx_handler(s, (span_tx_handler_t *) &silence_gen, &t->silence_gen);
set_next_tx_handler(s, (span_tx_handler_t *) &v29_tx, &t->v29_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->v17_tx, bit_rate, t->use_tep, short_train);
v17_tx_set_get_bit(&t->v17_tx, get_bit_func, get_bit_user_data);
set_tx_handler(s, (span_tx_handler_t *) &silence_gen, &t->silence_gen);
set_next_tx_handler(s, (span_tx_handler_t *) &v17_tx, &t->v17_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);
set_tx_handler(s, (span_tx_handler_t *) &silence_gen, &t->silence_gen);
set_next_tx_handler(s, (span_tx_handler_t *) NULL, NULL);
t->transmit = FALSE;
break;
}
t->tx_bit_rate = bit_rate;
t->current_tx_type = type;
}
static void fax_set_tx_type(void *user_data, int type, int short_train, int use_hdlc)
{
fax_state_t *s;
tone_gen_descriptor_t tone_desc;
get_bit_func_t get_bit_func;
void *get_bit_user_data;
s = (fax_state_t *) user_data;
span_log(&s->logging, SPAN_LOG_FLOW, "Set tx type %d\n", type);
if (s->current_tx_type == type)
return;
s->first_tx_hdlc_frame = TRUE;
if (use_hdlc)
{
get_bit_func = (get_bit_func_t) hdlc_tx_get_bit;
get_bit_user_data = (void *) &(s->hdlctx);
}
else
{
get_bit_func = t30_non_ecm_get_bit;
get_bit_user_data = (void *) &(s->t30_state);
}
switch (type)
{
case T30_MODEM_PAUSE:
silence_gen_alter(&(s->silence_gen), ms_to_samples(short_train));
s->tx_handler = (span_tx_handler_t *) &silence_gen;
s->tx_user_data = &(s->silence_gen);
s->next_tx_handler = NULL;
s->transmit = TRUE;
break;
case T30_MODEM_CNG:
/* 0.5s of 1100Hz+-38Hz + 3.0s of silence repeating. Timing +-15% */
make_tone_gen_descriptor(&tone_desc,
1100,
-11,
0,
0,
500,
3000,
0,
0,
TRUE);
tone_gen_init(&(s->tone_gen), &tone_desc);
s->tx_handler = (span_tx_handler_t *) &tone_gen;
s->tx_user_data = &(s->tone_gen);
s->next_tx_handler = NULL;
s->transmit = TRUE;
break;
case T30_MODEM_CED:
/* 0.2s of silence, then 2.6s to 4s of 2100Hz+-15Hz tone, then 75ms of silence. The 75ms of silence
will be inserted by the pre V.21 pause we use for any switch to V.21. */
silence_gen_alter(&(s->silence_gen), ms_to_samples(200));
make_tone_gen_descriptor(&tone_desc,
2100,
-11,
0,
0,
2600,
0,
0,
0,
FALSE);
tone_gen_init(&(s->tone_gen), &tone_desc);
s->tx_handler = (span_tx_handler_t *) &silence_gen;
s->tx_user_data = &(s->silence_gen);
s->next_tx_handler = (span_tx_handler_t *) &tone_gen;
s->next_tx_user_data = &(s->tone_gen);
s->transmit = TRUE;
break;
case T30_MODEM_V21:
fsk_tx_init(&(s->v21tx), &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(&(s->hdlctx), 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(&(s->silence_gen), ms_to_samples(75));
s->tx_handler = (span_tx_handler_t *) &silence_gen;
s->tx_user_data = &(s->silence_gen);
s->next_tx_handler = (span_tx_handler_t *) &fsk_tx;
s->next_tx_user_data = &(s->v21tx);
s->transmit = TRUE;
break;
case T30_MODEM_V27TER_2400:
silence_gen_alter(&(s->silence_gen), ms_to_samples(75));
v27ter_tx_restart(&(s->v27ter_tx), 2400, s->use_tep);
v27ter_tx_set_get_bit(&(s->v27ter_tx), get_bit_func, get_bit_user_data);
s->tx_handler = (span_tx_handler_t *) &silence_gen;
s->tx_user_data = &(s->silence_gen);
s->next_tx_handler = (span_tx_handler_t *) &v27ter_tx;
s->next_tx_user_data = &(s->v27ter_tx);
hdlc_tx_flags(&(s->hdlctx), 60);
s->transmit = TRUE;
break;
case T30_MODEM_V27TER_4800:
silence_gen_alter(&(s->silence_gen), ms_to_samples(75));
v27ter_tx_restart(&(s->v27ter_tx), 4800, s->use_tep);
v27ter_tx_set_get_bit(&(s->v27ter_tx), get_bit_func, get_bit_user_data);
s->tx_handler = (span_tx_handler_t *) &silence_gen;
s->tx_user_data = &(s->silence_gen);
s->next_tx_handler = (span_tx_handler_t *) &v27ter_tx;
s->next_tx_user_data = &(s->v27ter_tx);
hdlc_tx_flags(&(s->hdlctx), 120);
s->transmit = TRUE;
break;
case T30_MODEM_V29_7200:
silence_gen_alter(&(s->silence_gen), ms_to_samples(75));
v29_tx_restart(&(s->v29tx), 7200, s->use_tep);
v29_tx_set_get_bit(&(s->v29tx), get_bit_func, get_bit_user_data);
s->tx_handler = (span_tx_handler_t *) &silence_gen;
s->tx_user_data = &(s->silence_gen);
s->next_tx_handler = (span_tx_handler_t *) &v29_tx;
s->next_tx_user_data = &(s->v29tx);
hdlc_tx_flags(&(s->hdlctx), 180);
s->transmit = TRUE;
break;
case T30_MODEM_V29_9600:
silence_gen_alter(&(s->silence_gen), ms_to_samples(75));
v29_tx_restart(&(s->v29tx), 9600, s->use_tep);
v29_tx_set_get_bit(&(s->v29tx), get_bit_func, get_bit_user_data);
s->tx_handler = (span_tx_handler_t *) &silence_gen;
s->tx_user_data = &(s->silence_gen);
s->next_tx_handler = (span_tx_handler_t *) &v29_tx;
s->next_tx_user_data = &(s->v29tx);
hdlc_tx_flags(&(s->hdlctx), 240);
s->transmit = TRUE;
break;
case T30_MODEM_V17_7200:
silence_gen_alter(&(s->silence_gen), ms_to_samples(75));
v17_tx_restart(&(s->v17tx), 7200, s->use_tep, short_train);
v17_tx_set_get_bit(&(s->v17tx), get_bit_func, get_bit_user_data);
s->tx_handler = (span_tx_handler_t *) &silence_gen;
s->tx_user_data = &(s->silence_gen);
s->next_tx_handler = (span_tx_handler_t *) &v17_tx;
s->next_tx_user_data = &(s->v17tx);
hdlc_tx_flags(&(s->hdlctx), 180);
s->transmit = TRUE;
break;
case T30_MODEM_V17_9600:
silence_gen_alter(&(s->silence_gen), ms_to_samples(75));
v17_tx_restart(&(s->v17tx), 9600, s->use_tep, short_train);
v17_tx_set_get_bit(&(s->v17tx), get_bit_func, get_bit_user_data);
s->tx_handler = (span_tx_handler_t *) &silence_gen;
s->tx_user_data = &(s->silence_gen);
s->next_tx_handler = (span_tx_handler_t *) &v17_tx;
s->next_tx_user_data = &(s->v17tx);
hdlc_tx_flags(&(s->hdlctx), 240);
s->transmit = TRUE;
break;
case T30_MODEM_V17_12000:
silence_gen_alter(&(s->silence_gen), ms_to_samples(75));
v17_tx_restart(&(s->v17tx), 12000, s->use_tep, short_train);
v17_tx_set_get_bit(&(s->v17tx), get_bit_func, get_bit_user_data);
s->tx_handler = (span_tx_handler_t *) &silence_gen;
s->tx_user_data = &(s->silence_gen);
s->next_tx_handler = (span_tx_handler_t *) &v17_tx;
s->next_tx_user_data = &(s->v17tx);
hdlc_tx_flags(&(s->hdlctx), 300);
s->transmit = TRUE;
break;
case T30_MODEM_V17_14400:
silence_gen_alter(&(s->silence_gen), ms_to_samples(75));
v17_tx_restart(&(s->v17tx), 14400, s->use_tep, short_train);
v17_tx_set_get_bit(&(s->v17tx), get_bit_func, get_bit_user_data);
s->tx_handler = (span_tx_handler_t *) &silence_gen;
s->tx_user_data = &(s->silence_gen);
s->next_tx_handler = (span_tx_handler_t *) &v17_tx;
s->next_tx_user_data = &(s->v17tx);
hdlc_tx_flags(&(s->hdlctx), 360);
s->transmit = TRUE;
break;
case T30_MODEM_DONE:
span_log(&s->logging, SPAN_LOG_FLOW, "FAX exchange complete\n");
/* Fall through */
default:
silence_gen_alter(&(s->silence_gen), 0);
s->tx_handler = (span_tx_handler_t *) &silence_gen;
s->tx_user_data = &(s->silence_gen);
s->next_tx_handler = NULL;
s->transmit = FALSE;
break;
}
s->current_tx_type = type;
}
