static int transmit_audio(fax_session *s)
{
int res = -1;
struct ast_format original_read_fmt;
struct ast_format original_write_fmt;
fax_state_t fax;
t30_state_t *t30state;
struct ast_frame *inf = NULL;
int last_state = 0;
struct timeval now, start, state_change;
enum ast_t38_state t38_state;
struct ast_control_t38_parameters t38_parameters = { .version = 0,
.max_ifp = 800,
.rate = AST_T38_RATE_14400,
.rate_management = AST_T38_RATE_MANAGEMENT_TRANSFERRED_TCF,
.fill_bit_removal = 1,
/*
* spandsp has API calls to support MMR and JBIG transcoding, but they aren't
* implemented quite yet... so don't offer them to the remote endpoint
* .transcoding_mmr = 1,
* .transcoding_jbig = 1,
*/
};
ast_format_clear(&original_read_fmt);
ast_format_clear(&original_write_fmt);
/* if in called party mode, try to use T.38 */
if (s->caller_mode == FALSE) {
/* check if we are already in T.38 mode (unlikely), or if we can request
* a switch... if so, request it now and wait for the result, rather
* than starting an audio FAX session that will have to be cancelled
*/
if ((t38_state = ast_channel_get_t38_state(s->chan)) == T38_STATE_NEGOTIATED) {
return 1;
} else if ((t38_state != T38_STATE_UNAVAILABLE) &&
(t38_parameters.request_response = AST_T38_REQUEST_NEGOTIATE,
(ast_indicate_data(s->chan, AST_CONTROL_T38_PARAMETERS, &t38_parameters, sizeof(t38_parameters)) == 0))) {
/* wait up to five seconds for negotiation to complete */
unsigned int timeout = 5000;
int ms;
ast_debug(1, "Negotiating T.38 for receive on %s\n", ast_channel_name(s->chan));
while (timeout > 0) {
ms = ast_waitfor(s->chan, 1000);
if (ms < 0) {
ast_log(LOG_WARNING, "something bad happened while channel '%s' was polling.\n", ast_channel_name(s->chan));
return -1;
}
if (!ms) {
/* nothing happened */
if (timeout > 0) {
timeout -= 1000;
continue;
} else {
ast_log(LOG_WARNING, "channel '%s' timed-out during the T.38 negotiation.\n", ast_channel_name(s->chan));
break;
}
}
if (!(inf = ast_read(s->chan))) {
return -1;
}
if ((inf->frametype == AST_FRAME_CONTROL) &&
(inf->subclass.integer == AST_CONTROL_T38_PARAMETERS) &&
(inf->datalen == sizeof(t38_parameters))) {
struct ast_control_t38_parameters *parameters = inf->data.ptr;
switch (parameters->request_response) {
case AST_T38_NEGOTIATED:
ast_debug(1, "Negotiated T.38 for receive on %s\n", ast_channel_name(s->chan));
res = 1;
break;
case AST_T38_REFUSED:
ast_log(LOG_WARNING, "channel '%s' refused to negotiate T.38\n", ast_channel_name(s->chan));
break;
default:
ast_log(LOG_ERROR, "channel '%s' failed to negotiate T.38\n", ast_channel_name(s->chan));
break;
}
ast_frfree(inf);
if (res == 1) {
return 1;
} else {
break;
}
}
ast_frfree(inf);
}
}
}
#if SPANDSP_RELEASE_DATE >= 20080725
/* for spandsp shaphots 0.0.6 and higher */
t30state = &fax.t30;
#else
/* for spandsp release 0.0.5 */
t30state = &fax.t30_state;
#endif
ast_format_copy(&original_read_fmt, ast_channel_readformat(s->chan));
if (original_read_fmt.id != AST_FORMAT_SLINEAR) {
res = ast_set_read_format_by_id(s->chan, AST_FORMAT_SLINEAR);
if (res < 0) {
ast_log(LOG_WARNING, "Unable to set to linear read mode, giving up\n");
goto done;
}
}
ast_format_copy(&original_write_fmt, ast_channel_writeformat(s->chan));
if (original_write_fmt.id != AST_FORMAT_SLINEAR) {
res = ast_set_write_format_by_id(s->chan, AST_FORMAT_SLINEAR);
if (res < 0) {
ast_log(LOG_WARNING, "Unable to set to linear write mode, giving up\n");
goto done;
}
}
/* Initialize T30 terminal */
fax_init(&fax, s->caller_mode);
/* Setup logging */
set_logging(&fax.logging);
set_logging(&t30state->logging);
/* Configure terminal */
set_local_info(t30state, s);
set_file(t30state, s);
set_ecm(t30state, TRUE);
fax_set_transmit_on_idle(&fax, TRUE);
t30_set_phase_e_handler(t30state, phase_e_handler, s);
start = state_change = ast_tvnow();
ast_activate_generator(s->chan, &generator, &fax);
while (!s->finished) {
inf = NULL;
if ((res = ast_waitfor(s->chan, 25)) < 0) {
ast_debug(1, "Error waiting for a frame\n");
break;
}
/* Watchdog */
now = ast_tvnow();
if (ast_tvdiff_sec(now, start) > WATCHDOG_TOTAL_TIMEOUT || ast_tvdiff_sec(now, state_change) > WATCHDOG_STATE_TIMEOUT) {
ast_log(LOG_WARNING, "It looks like we hung. Aborting.\n");
res = -1;
break;
}
if (!res) {
/* There was timeout waiting for a frame. Loop around and wait again */
continue;
}
/* There is a frame available. Get it */
res = 0;
if (!(inf = ast_read(s->chan))) {
ast_debug(1, "Channel hangup\n");
res = -1;
break;
}
ast_debug(10, "frame %d/%u, len=%d\n", inf->frametype, (unsigned int) inf->subclass.format.id, inf->datalen);
/* Check the frame type. Format also must be checked because there is a chance
that a frame in old format was already queued before we set channel format
to slinear so it will still be received by ast_read */
if (inf->frametype == AST_FRAME_VOICE && inf->subclass.format.id == AST_FORMAT_SLINEAR) {
if (fax_rx(&fax, inf->data.ptr, inf->samples) < 0) {
/* I know fax_rx never returns errors. The check here is for good style only */
ast_log(LOG_WARNING, "fax_rx returned error\n");
res = -1;
break;
}
if (last_state != t30state->state) {
state_change = ast_tvnow();
last_state = t30state->state;
}
} else if ((inf->frametype == AST_FRAME_CONTROL) &&
(inf->subclass.integer == AST_CONTROL_T38_PARAMETERS)) {
struct ast_control_t38_parameters *parameters = inf->data.ptr;
if (parameters->request_response == AST_T38_NEGOTIATED) {
/* T38 switchover completed */
s->t38parameters = *parameters;
ast_debug(1, "T38 negotiated, finishing audio loop\n");
res = 1;
break;
} else if (parameters->request_response == AST_T38_REQUEST_NEGOTIATE) {
t38_parameters.request_response = AST_T38_NEGOTIATED;
ast_debug(1, "T38 request received, accepting\n");
/* Complete T38 switchover */
ast_indicate_data(s->chan, AST_CONTROL_T38_PARAMETERS, &t38_parameters, sizeof(t38_parameters));
/* Do not break audio loop, wait until channel driver finally acks switchover
* with AST_T38_NEGOTIATED
*/
}
}
ast_frfree(inf);
inf = NULL;
}
ast_debug(1, "Loop finished, res=%d\n", res);
if (inf)
ast_frfree(inf);
ast_deactivate_generator(s->chan);
/* If we are switching to T38, remove phase E handler. Otherwise it will be executed
by t30_terminate, display diagnostics and set status variables although no transmittion
has taken place yet. */
if (res > 0) {
t30_set_phase_e_handler(t30state, NULL, NULL);
}
t30_terminate(t30state);
fax_release(&fax);
done:
if (original_write_fmt.id != AST_FORMAT_SLINEAR) {
if (ast_set_write_format(s->chan, &original_write_fmt) < 0)
ast_log(LOG_WARNING, "Unable to restore write format on '%s'\n", ast_channel_name(s->chan));
}
if (original_read_fmt.id != AST_FORMAT_SLINEAR) {
if (ast_set_read_format(s->chan, &original_read_fmt) < 0)
ast_log(LOG_WARNING, "Unable to restore read format on '%s'\n", ast_channel_name(s->chan));
}
return res;
}
static int transmit_t38(fax_session *s)
{
int res = 0;
t38_terminal_state_t t38;
struct ast_frame *inf = NULL;
int last_state = 0;
struct timeval now, start, state_change, last_frame;
t30_state_t *t30state;
t38_core_state_t *t38state;
#if SPANDSP_RELEASE_DATE >= 20080725
/* for spandsp shaphots 0.0.6 and higher */
t30state = &t38.t30;
t38state = &t38.t38_fe.t38;
#else
/* for spandsp releases 0.0.5 */
t30state = &t38.t30_state;
t38state = &t38.t38;
#endif
/* Initialize terminal */
memset(&t38, 0, sizeof(t38));
if (t38_terminal_init(&t38, s->caller_mode, t38_tx_packet_handler, s->chan) == NULL) {
ast_log(LOG_WARNING, "Unable to start T.38 termination.\n");
res = -1;
goto disable_t38;
}
t38_set_max_datagram_size(t38state, s->t38parameters.max_ifp);
if (s->t38parameters.fill_bit_removal) {
t38_set_fill_bit_removal(t38state, TRUE);
}
if (s->t38parameters.transcoding_mmr) {
t38_set_mmr_transcoding(t38state, TRUE);
}
if (s->t38parameters.transcoding_jbig) {
t38_set_jbig_transcoding(t38state, TRUE);
}
/* Setup logging */
set_logging(&t38.logging);
set_logging(&t30state->logging);
set_logging(&t38state->logging);
/* Configure terminal */
set_local_info(t30state, s);
set_file(t30state, s);
set_ecm(t30state, TRUE);
t30_set_phase_e_handler(t30state, phase_e_handler, s);
now = start = state_change = ast_tvnow();
while (!s->finished) {
inf = NULL;
if ((res = ast_waitfor(s->chan, 25)) < 0) {
ast_debug(1, "Error waiting for a frame\n");
break;
}
last_frame = now;
/* Watchdog */
now = ast_tvnow();
if (ast_tvdiff_sec(now, start) > WATCHDOG_TOTAL_TIMEOUT || ast_tvdiff_sec(now, state_change) > WATCHDOG_STATE_TIMEOUT) {
ast_log(LOG_WARNING, "It looks like we hung. Aborting.\n");
res = -1;
break;
}
t38_terminal_send_timeout(&t38, ast_tvdiff_us(now, last_frame) / (1000000 / 8000));
if (!res) {
/* There was timeout waiting for a frame. Loop around and wait again */
continue;
}
/* There is a frame available. Get it */
res = 0;
if (!(inf = ast_read(s->chan))) {
ast_debug(1, "Channel hangup\n");
res = -1;
break;
}
ast_debug(10, "frame %d/%d, len=%d\n", inf->frametype, inf->subclass.integer, inf->datalen);
if (inf->frametype == AST_FRAME_MODEM && inf->subclass.integer == AST_MODEM_T38) {
t38_core_rx_ifp_packet(t38state, inf->data.ptr, inf->datalen, inf->seqno);
if (last_state != t30state->state) {
state_change = ast_tvnow();
last_state = t30state->state;
}
} else if (inf->frametype == AST_FRAME_CONTROL && inf->subclass.integer == AST_CONTROL_T38_PARAMETERS) {
struct ast_control_t38_parameters *parameters = inf->data.ptr;
if (parameters->request_response == AST_T38_TERMINATED) {
ast_debug(1, "T38 down, finishing\n");
break;
}
}
ast_frfree(inf);
inf = NULL;
}
ast_debug(1, "Loop finished, res=%d\n", res);
if (inf)
ast_frfree(inf);
t30_terminate(t30state);
t38_terminal_release(&t38);
disable_t38:
/* if we are not the caller, it's our job to shut down the T.38
* session when the FAX transmisson is complete.
*/
if ((s->caller_mode == FALSE) &&
(ast_channel_get_t38_state(s->chan) == T38_STATE_NEGOTIATED)) {
struct ast_control_t38_parameters t38_parameters = { .request_response = AST_T38_REQUEST_TERMINATE, };
if (ast_indicate_data(s->chan, AST_CONTROL_T38_PARAMETERS, &t38_parameters, sizeof(t38_parameters)) == 0) {
/* wait up to five seconds for negotiation to complete */
unsigned int timeout = 5000;
int ms;
ast_debug(1, "Shutting down T.38 on %s\n", ast_channel_name(s->chan));
while (timeout > 0) {
ms = ast_waitfor(s->chan, 1000);
if (ms < 0) {
ast_log(LOG_WARNING, "something bad happened while channel '%s' was polling.\n", ast_channel_name(s->chan));
return -1;
}
if (!ms) {
/* nothing happened */
if (timeout > 0) {
timeout -= 1000;
continue;
} else {
ast_log(LOG_WARNING, "channel '%s' timed-out during the T.38 shutdown.\n", ast_channel_name(s->chan));
break;
}
}
if (!(inf = ast_read(s->chan))) {
return -1;
}
if ((inf->frametype == AST_FRAME_CONTROL) &&
(inf->subclass.integer == AST_CONTROL_T38_PARAMETERS) &&
(inf->datalen == sizeof(t38_parameters))) {
struct ast_control_t38_parameters *parameters = inf->data.ptr;
switch (parameters->request_response) {
case AST_T38_TERMINATED:
ast_debug(1, "Shut down T.38 on %s\n", ast_channel_name(s->chan));
break;
case AST_T38_REFUSED:
ast_log(LOG_WARNING, "channel '%s' refused to disable T.38\n", ast_channel_name(s->chan));
break;
default:
ast_log(LOG_ERROR, "channel '%s' failed to disable T.38\n", ast_channel_name(s->chan));
break;
}
ast_frfree(inf);
break;
}
ast_frfree(inf);
}
}
}
return res;
}
static int transmit_audio(fax_session *s)
{
int res = -1;
int original_read_fmt = AST_FORMAT_SLINEAR;
int original_write_fmt = AST_FORMAT_SLINEAR;
fax_state_t fax;
struct ast_dsp *dsp = NULL;
int detect_tone = 0;
struct ast_frame *inf = NULL;
struct ast_frame *fr;
int last_state = 0;
struct timeval now, start, state_change;
enum ast_control_t38 t38control;
original_read_fmt = s->chan->readformat;
if (original_read_fmt != AST_FORMAT_SLINEAR) {
res = ast_set_read_format(s->chan, AST_FORMAT_SLINEAR);
if (res < 0) {
ast_log(LOG_WARNING, "Unable to set to linear read mode, giving up\n");
goto done;
}
}
original_write_fmt = s->chan->writeformat;
if (original_write_fmt != AST_FORMAT_SLINEAR) {
res = ast_set_write_format(s->chan, AST_FORMAT_SLINEAR);
if (res < 0) {
ast_log(LOG_WARNING, "Unable to set to linear write mode, giving up\n");
goto done;
}
}
/* Initialize T30 terminal */
fax_init(&fax, s->caller_mode);
/* Setup logging */
set_logging(&fax.logging);
set_logging(&fax.t30_state.logging);
/* Configure terminal */
set_local_info(&fax.t30_state, s);
set_file(&fax.t30_state, s);
set_ecm(&fax.t30_state, TRUE);
fax_set_transmit_on_idle(&fax, TRUE);
t30_set_phase_e_handler(&fax.t30_state, phase_e_handler, s);
if (s->t38state == T38_STATE_UNAVAILABLE) {
ast_debug(1, "T38 is unavailable on %s\n", s->chan->name);
} else if (!s->direction) {
/* We are receiving side and this means we are the side which should
request T38 when the fax is detected. Use DSP to detect fax tone */
ast_debug(1, "Setting up CNG detection on %s\n", s->chan->name);
dsp = ast_dsp_new();
ast_dsp_set_features(dsp, DSP_FEATURE_FAX_DETECT);
ast_dsp_set_faxmode(dsp, DSP_FAXMODE_DETECT_CNG);
detect_tone = 1;
}
start = state_change = ast_tvnow();
ast_activate_generator(s->chan, &generator, &fax);
while (!s->finished) {
res = ast_waitfor(s->chan, 20);
if (res < 0)
break;
else if (res > 0)
res = 0;
inf = ast_read(s->chan);
if (inf == NULL) {
ast_debug(1, "Channel hangup\n");
res = -1;
break;
}
ast_debug(10, "frame %d/%d, len=%d\n", inf->frametype, inf->subclass, inf->datalen);
/* Detect fax tone */
if (detect_tone && inf->frametype == AST_FRAME_VOICE) {
/* Duplicate frame because ast_dsp_process may free the frame passed */
fr = ast_frdup(inf);
/* Do not pass channel to ast_dsp_process otherwise it may queue modified audio frame back */
fr = ast_dsp_process(NULL, dsp, fr);
if (fr && fr->frametype == AST_FRAME_DTMF && fr->subclass == 'f') {
ast_debug(1, "Fax tone detected. Requesting T38\n");
t38control = AST_T38_REQUEST_NEGOTIATE;
ast_indicate_data(s->chan, AST_CONTROL_T38, &t38control, sizeof(t38control));
detect_tone = 0;
}
ast_frfree(fr);
}
/* Check the frame type. Format also must be checked because there is a chance
that a frame in old format was already queued before we set chanel format
to slinear so it will still be received by ast_read */
if (inf->frametype == AST_FRAME_VOICE && inf->subclass == AST_FORMAT_SLINEAR) {
if (fax_rx(&fax, inf->data, inf->samples) < 0) {
/* I know fax_rx never returns errors. The check here is for good style only */
ast_log(LOG_WARNING, "fax_rx returned error\n");
res = -1;
break;
}
/* Watchdog */
if (last_state != fax.t30_state.state) {
state_change = ast_tvnow();
last_state = fax.t30_state.state;
}
} else if (inf->frametype == AST_FRAME_CONTROL && inf->subclass == AST_CONTROL_T38 &&
inf->datalen == sizeof(enum ast_control_t38)) {
t38control =*((enum ast_control_t38 *) inf->data);
if (t38control == AST_T38_NEGOTIATED) {
/* T38 switchover completed */
ast_debug(1, "T38 negotiated, finishing audio loop\n");
res = 1;
break;
}
}
ast_frfree(inf);
inf = NULL;
/* Watchdog */
now = ast_tvnow();
if (ast_tvdiff_sec(now, start) > WATCHDOG_TOTAL_TIMEOUT || ast_tvdiff_sec(now, state_change) > WATCHDOG_STATE_TIMEOUT) {
ast_log(LOG_WARNING, "It looks like we hung. Aborting.\n");
res = -1;
break;
}
}
ast_debug(1, "Loop finished, res=%d\n", res);
if (inf)
ast_frfree(inf);
if (dsp)
ast_dsp_free(dsp);
ast_deactivate_generator(s->chan);
/* If we are switching to T38, remove phase E handler. Otherwise it will be executed
by t30_terminate, display diagnostics and set status variables although no transmittion
has taken place yet. */
if (res > 0) {
t30_set_phase_e_handler(&fax.t30_state, NULL, NULL);
}
t30_terminate(&fax.t30_state);
fax_release(&fax);
done:
if (original_write_fmt != AST_FORMAT_SLINEAR) {
if (ast_set_write_format(s->chan, original_write_fmt) < 0)
ast_log(LOG_WARNING, "Unable to restore write format on '%s'\n", s->chan->name);
}
if (original_read_fmt != AST_FORMAT_SLINEAR) {
if (ast_set_read_format(s->chan, original_read_fmt) < 0)
ast_log(LOG_WARNING, "Unable to restore read format on '%s'\n", s->chan->name);
}
return res;
}