asterisk/apps/app_fax.c

1006 lines
29 KiB
C

/*
* Asterisk -- An open source telephony toolkit.
*
* Simple fax applications
*
* 2007-2008, Dmitry Andrianov <asterisk@dima.spb.ru>
*
* Code based on original implementation by Steve Underwood <steveu@coppice.org>
*
* This program is free software, distributed under the terms of
* the GNU General Public License
*
*/
/*** MODULEINFO
<depend>spandsp</depend>
<conflict>res_fax</conflict>
<defaultenabled>no</defaultenabled>
<support_level>deprecated</support_level>
<replacement>res_fax</replacement>
<deprecated_in>16</deprecated_in>
<removed_in>19</removed_in>
***/
/* Needed for spandsp headers */
#define ASTMM_LIBC ASTMM_IGNORE
#include "asterisk.h"
#include <string.h>
#include <stdlib.h>
#include <stdio.h>
#include <inttypes.h>
#include <pthread.h>
#include <errno.h>
#include <tiffio.h>
#define SPANDSP_EXPOSE_INTERNAL_STRUCTURES
#include <spandsp.h>
#include <spandsp/version.h>
#include "asterisk/lock.h"
#include "asterisk/file.h"
#include "asterisk/logger.h"
#include "asterisk/channel.h"
#include "asterisk/pbx.h"
#include "asterisk/app.h"
#include "asterisk/dsp.h"
#include "asterisk/module.h"
#include "asterisk/stasis.h"
#include "asterisk/stasis_channels.h"
#include "asterisk/format_cache.h"
/*** DOCUMENTATION
<application name="SendFAX" language="en_US" module="app_fax">
<synopsis>
Send a Fax
</synopsis>
<syntax>
<parameter name="filename" required="true">
<para>Filename of TIFF file to fax</para>
</parameter>
<parameter name="a" required="false">
<para>Makes the application behave as the answering machine</para>
<para>(Default behavior is as calling machine)</para>
</parameter>
</syntax>
<description>
<para>Send a given TIFF file to the channel as a FAX.</para>
<para>This application sets the following channel variables:</para>
<variablelist>
<variable name="LOCALSTATIONID">
<para>To identify itself to the remote end</para>
</variable>
<variable name="LOCALHEADERINFO">
<para>To generate a header line on each page</para>
</variable>
<variable name="FAXSTATUS">
<value name="SUCCESS"/>
<value name="FAILED"/>
</variable>
<variable name="FAXERROR">
<para>Cause of failure</para>
</variable>
<variable name="REMOTESTATIONID">
<para>The CSID of the remote side</para>
</variable>
<variable name="FAXPAGES">
<para>Number of pages sent</para>
</variable>
<variable name="FAXBITRATE">
<para>Transmission rate</para>
</variable>
<variable name="FAXRESOLUTION">
<para>Resolution of sent fax</para>
</variable>
</variablelist>
</description>
</application>
<application name="ReceiveFAX" language="en_US" module="app_fax">
<synopsis>
Receive a Fax
</synopsis>
<syntax>
<parameter name="filename" required="true">
<para>Filename of TIFF file save incoming fax</para>
</parameter>
<parameter name="c" required="false">
<para>Makes the application behave as the calling machine</para>
<para>(Default behavior is as answering machine)</para>
</parameter>
</syntax>
<description>
<para>Receives a FAX from the channel into the given filename
overwriting the file if it already exists.</para>
<para>File created will be in TIFF format.</para>
<para>This application sets the following channel variables:</para>
<variablelist>
<variable name="LOCALSTATIONID">
<para>To identify itself to the remote end</para>
</variable>
<variable name="LOCALHEADERINFO">
<para>To generate a header line on each page</para>
</variable>
<variable name="FAXSTATUS">
<value name="SUCCESS"/>
<value name="FAILED"/>
</variable>
<variable name="FAXERROR">
<para>Cause of failure</para>
</variable>
<variable name="REMOTESTATIONID">
<para>The CSID of the remote side</para>
</variable>
<variable name="FAXPAGES">
<para>Number of pages sent</para>
</variable>
<variable name="FAXBITRATE">
<para>Transmission rate</para>
</variable>
<variable name="FAXRESOLUTION">
<para>Resolution of sent fax</para>
</variable>
</variablelist>
</description>
</application>
***/
static const char app_sndfax_name[] = "SendFAX";
static const char app_rcvfax_name[] = "ReceiveFAX";
#define MAX_SAMPLES 240
/* Watchdog. I have seen situations when remote fax disconnects (because of poor line
quality) while SpanDSP continues staying in T30_STATE_IV_CTC state forever.
To avoid this, we terminate when we see that T30 state does not change for 5 minutes.
We also terminate application when more than 30 minutes passed regardless of
state changes. This is just a precaution measure - no fax should take that long */
#define WATCHDOG_TOTAL_TIMEOUT 30 * 60
#define WATCHDOG_STATE_TIMEOUT 5 * 60
typedef struct {
struct ast_channel *chan;
enum ast_t38_state t38state; /* T38 state of the channel */
int direction; /* Fax direction: 0 - receiving, 1 - sending */
int caller_mode;
char *file_name;
struct ast_control_t38_parameters t38parameters;
volatile int finished;
} fax_session;
static void span_message(int level, const char *msg)
{
if (level == SPAN_LOG_ERROR) {
ast_log(LOG_ERROR, "%s", msg);
} else if (level == SPAN_LOG_WARNING) {
ast_log(LOG_WARNING, "%s", msg);
} else {
ast_debug(1, "%s", msg);
}
}
static int t38_tx_packet_handler(t38_core_state_t *s, void *user_data, const uint8_t *buf, int len, int count)
{
struct ast_channel *chan = (struct ast_channel *) user_data;
struct ast_frame outf = {
.frametype = AST_FRAME_MODEM,
.subclass.integer = AST_MODEM_T38,
.src = __FUNCTION__,
};
/* TODO: Asterisk does not provide means of resending the same packet multiple
times so count is ignored at the moment */
AST_FRAME_SET_BUFFER(&outf, buf, 0, len);
if (ast_write(chan, &outf) < 0) {
ast_log(LOG_WARNING, "Unable to write frame to channel; %s\n", strerror(errno));
return -1;
}
return 0;
}
static void phase_e_handler(t30_state_t *f, void *user_data, int result)
{
RAII_VAR(struct ast_json *, json_object, NULL, ast_json_unref);
RAII_VAR(struct ast_json *, json_filenames, NULL, ast_json_unref);
RAII_VAR(struct stasis_message *, message, NULL, ao2_cleanup);
const char *local_ident;
const char *far_ident;
char buf[20];
fax_session *s = (fax_session *) user_data;
t30_stats_t stat;
int pages_transferred;
ast_debug(1, "Fax phase E handler. result=%d\n", result);
t30_get_transfer_statistics(f, &stat);
s = (fax_session *) user_data;
if (result != T30_ERR_OK) {
s->finished = -1;
/* FAXSTATUS is already set to FAILED */
pbx_builtin_setvar_helper(s->chan, "FAXERROR", t30_completion_code_to_str(result));
ast_log(LOG_WARNING, "Error transmitting fax. result=%d: %s.\n", result, t30_completion_code_to_str(result));
return;
}
s->finished = 1;
local_ident = S_OR(t30_get_tx_ident(f), "");
far_ident = S_OR(t30_get_rx_ident(f), "");
pbx_builtin_setvar_helper(s->chan, "FAXSTATUS", "SUCCESS");
pbx_builtin_setvar_helper(s->chan, "FAXERROR", NULL);
pbx_builtin_setvar_helper(s->chan, "REMOTESTATIONID", far_ident);
#if SPANDSP_RELEASE_DATE >= 20090220
pages_transferred = (s->direction) ? stat.pages_tx : stat.pages_rx;
#else
pages_transferred = stat.pages_transferred;
#endif
snprintf(buf, sizeof(buf), "%d", pages_transferred);
pbx_builtin_setvar_helper(s->chan, "FAXPAGES", buf);
snprintf(buf, sizeof(buf), "%d", stat.y_resolution);
pbx_builtin_setvar_helper(s->chan, "FAXRESOLUTION", buf);
snprintf(buf, sizeof(buf), "%d", stat.bit_rate);
pbx_builtin_setvar_helper(s->chan, "FAXBITRATE", buf);
ast_debug(1, "Fax transmitted successfully.\n");
ast_debug(1, " Remote station ID: %s\n", far_ident);
ast_debug(1, " Pages transferred: %d\n", pages_transferred);
ast_debug(1, " Image resolution: %d x %d\n", stat.x_resolution, stat.y_resolution);
ast_debug(1, " Transfer Rate: %d\n", stat.bit_rate);
json_filenames = ast_json_pack("[s]", s->file_name);
if (!json_filenames) {
return;
}
ast_json_ref(json_filenames);
json_object = ast_json_pack("{s: s, s: s, s: s, s: i, s: i, s: i, s: o}",
"type", s->direction ? "send" : "receive",
"remote_station_id", AST_JSON_UTF8_VALIDATE(far_ident),
"local_station_id", AST_JSON_UTF8_VALIDATE(local_ident),
"fax_pages", pages_transferred,
"fax_resolution", stat.y_resolution,
"fax_bitrate", stat.bit_rate,
"filenames", json_filenames);
message = ast_channel_blob_create_from_cache(ast_channel_uniqueid(s->chan), ast_channel_fax_type(), json_object);
if (!message) {
return;
}
stasis_publish(ast_channel_topic(s->chan), message);
}
/* === Helper functions to configure fax === */
/* Setup SPAN logging according to Asterisk debug level */
static int set_logging(logging_state_t *state)
{
int level = SPAN_LOG_WARNING + option_debug;
span_log_set_message_handler(state, span_message);
span_log_set_level(state, SPAN_LOG_SHOW_SEVERITY | SPAN_LOG_SHOW_PROTOCOL | level);
return 0;
}
static void set_local_info(t30_state_t *state, fax_session *s)
{
const char *x;
x = pbx_builtin_getvar_helper(s->chan, "LOCALSTATIONID");
if (!ast_strlen_zero(x))
t30_set_tx_ident(state, x);
x = pbx_builtin_getvar_helper(s->chan, "LOCALHEADERINFO");
if (!ast_strlen_zero(x))
t30_set_tx_page_header_info(state, x);
}
static void set_file(t30_state_t *state, fax_session *s)
{
if (s->direction)
t30_set_tx_file(state, s->file_name, -1, -1);
else
t30_set_rx_file(state, s->file_name, -1);
}
static void set_ecm(t30_state_t *state, int ecm)
{
t30_set_ecm_capability(state, ecm);
t30_set_supported_compressions(state, T30_SUPPORT_T4_1D_COMPRESSION | T30_SUPPORT_T4_2D_COMPRESSION | T30_SUPPORT_T6_COMPRESSION);
}
/* === Generator === */
/* This function is only needed to return passed params so
generator_activate will save it to channel's generatordata */
static void *fax_generator_alloc(struct ast_channel *chan, void *params)
{
return params;
}
static int fax_generator_generate(struct ast_channel *chan, void *data, int len, int samples)
{
fax_state_t *fax = (fax_state_t*) data;
uint8_t buffer[AST_FRIENDLY_OFFSET + MAX_SAMPLES * sizeof(uint16_t)];
int16_t *buf = (int16_t *) (buffer + AST_FRIENDLY_OFFSET);
struct ast_frame outf = {
.frametype = AST_FRAME_VOICE,
.subclass.format = ast_format_slin,
.src = __FUNCTION__,
};
if (samples > MAX_SAMPLES) {
ast_log(LOG_WARNING, "Only generating %d samples, where %d requested\n", MAX_SAMPLES, samples);
samples = MAX_SAMPLES;
}
if ((len = fax_tx(fax, buf, samples)) > 0) {
outf.samples = len;
AST_FRAME_SET_BUFFER(&outf, buffer, AST_FRIENDLY_OFFSET, len * sizeof(int16_t));
if (ast_write(chan, &outf) < 0) {
ast_log(LOG_WARNING, "Failed to write frame to '%s': %s\n", ast_channel_name(chan), strerror(errno));
return -1;
}
}
return 0;
}
static struct ast_generator generator = {
.alloc = fax_generator_alloc,
.generate = fax_generator_generate,
};
/* === Transmission === */
static int transmit_audio(fax_session *s)
{
int res = -1;
struct ast_format *original_read_fmt;
struct ast_format *original_write_fmt = NULL;
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,
*/
};
/* 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
original_read_fmt = ao2_bump(ast_channel_readformat(s->chan));
res = ast_set_read_format(s->chan, ast_format_slin);
if (res < 0) {
ast_log(LOG_WARNING, "Unable to set to linear read mode, giving up\n");
goto done;
}
original_write_fmt = ao2_bump(ast_channel_writeformat(s->chan));
res = ast_set_write_format(s->chan, ast_format_slin);
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/%s, len=%d\n", inf->frametype, ast_format_get_name(inf->subclass.format), 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 &&
(ast_format_cmp(inf->subclass.format, ast_format_slin) == AST_FORMAT_CMP_EQUAL)) {
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) {
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));
ao2_ref(original_write_fmt, -1);
}
if (original_read_fmt) {
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));
ao2_ref(original_read_fmt, -1);
}
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(fax_session *s)
{
int res = 0;
/* Clear all channel variables which to be set by the application.
Pre-set status to error so in case of any problems we can just leave */
pbx_builtin_setvar_helper(s->chan, "FAXSTATUS", "FAILED");
pbx_builtin_setvar_helper(s->chan, "FAXERROR", "Channel problems");
pbx_builtin_setvar_helper(s->chan, "FAXMODE", NULL);
pbx_builtin_setvar_helper(s->chan, "REMOTESTATIONID", NULL);
pbx_builtin_setvar_helper(s->chan, "FAXPAGES", "0");
pbx_builtin_setvar_helper(s->chan, "FAXRESOLUTION", NULL);
pbx_builtin_setvar_helper(s->chan, "FAXBITRATE", NULL);
if (ast_channel_state(s->chan) != AST_STATE_UP) {
/* Shouldn't need this, but checking to see if channel is already answered
* Theoretically asterisk should already have answered before running the app */
res = ast_answer(s->chan);
if (res) {
ast_log(LOG_WARNING, "Could not answer channel '%s'\n", ast_channel_name(s->chan));
return res;
}
}
s->t38state = ast_channel_get_t38_state(s->chan);
if (s->t38state != T38_STATE_NEGOTIATED) {
/* T38 is not negotiated on the channel yet. First start regular transmission. If it switches to T38, follow */
pbx_builtin_setvar_helper(s->chan, "FAXMODE", "audio");
res = transmit_audio(s);
if (res > 0) {
/* transmit_audio reports switchover to T38. Update t38state */
s->t38state = ast_channel_get_t38_state(s->chan);
if (s->t38state != T38_STATE_NEGOTIATED) {
ast_log(LOG_ERROR, "Audio loop reports T38 switchover but t38state != T38_STATE_NEGOTIATED\n");
}
}
}
if (s->t38state == T38_STATE_NEGOTIATED) {
pbx_builtin_setvar_helper(s->chan, "FAXMODE", "T38");
res = transmit_t38(s);
}
if (res) {
ast_log(LOG_WARNING, "Transmission error\n");
res = -1;
} else if (s->finished < 0) {
ast_log(LOG_WARNING, "Transmission failed\n");
} else if (s->finished > 0) {
ast_debug(1, "Transmission finished Ok\n");
}
return res;
}
/* === Application functions === */
static int sndfax_exec(struct ast_channel *chan, const char *data)
{
int res = 0;
char *parse;
fax_session session = { 0, };
char restore_digit_detect = 0;
AST_DECLARE_APP_ARGS(args,
AST_APP_ARG(file_name);
AST_APP_ARG(options);
);
if (chan == NULL) {
ast_log(LOG_ERROR, "Fax channel is NULL. Giving up.\n");
return -1;
}
/* The next few lines of code parse out the filename and header from the input string */
if (ast_strlen_zero(data)) {
/* No data implies no filename or anything is present */
ast_log(LOG_ERROR, "SendFAX requires an argument (filename)\n");
return -1;
}
parse = ast_strdupa(data);
AST_STANDARD_APP_ARGS(args, parse);
session.caller_mode = TRUE;
if (args.options) {
if (strchr(args.options, 'a'))
session.caller_mode = FALSE;
}
/* Done parsing */
session.direction = 1;
session.file_name = args.file_name;
session.chan = chan;
session.finished = 0;
/* get current digit detection mode, then disable digit detection if enabled */
{
int dummy = sizeof(restore_digit_detect);
ast_channel_queryoption(chan, AST_OPTION_DIGIT_DETECT, &restore_digit_detect, &dummy, 0);
}
if (restore_digit_detect) {
char new_digit_detect = 0;
ast_channel_setoption(chan, AST_OPTION_DIGIT_DETECT, &new_digit_detect, sizeof(new_digit_detect), 0);
}
/* disable FAX tone detection if enabled */
{
char new_fax_detect = 0;
ast_channel_setoption(chan, AST_OPTION_FAX_DETECT, &new_fax_detect, sizeof(new_fax_detect), 0);
}
res = transmit(&session);
if (restore_digit_detect) {
ast_channel_setoption(chan, AST_OPTION_DIGIT_DETECT, &restore_digit_detect, sizeof(restore_digit_detect), 0);
}
return res;
}
static int rcvfax_exec(struct ast_channel *chan, const char *data)
{
int res = 0;
char *parse;
fax_session session;
char restore_digit_detect = 0;
AST_DECLARE_APP_ARGS(args,
AST_APP_ARG(file_name);
AST_APP_ARG(options);
);
if (chan == NULL) {
ast_log(LOG_ERROR, "Fax channel is NULL. Giving up.\n");
return -1;
}
/* The next few lines of code parse out the filename and header from the input string */
if (ast_strlen_zero(data)) {
/* No data implies no filename or anything is present */
ast_log(LOG_ERROR, "ReceiveFAX requires an argument (filename)\n");
return -1;
}
parse = ast_strdupa(data);
AST_STANDARD_APP_ARGS(args, parse);
session.caller_mode = FALSE;
if (args.options) {
if (strchr(args.options, 'c'))
session.caller_mode = TRUE;
}
/* Done parsing */
session.direction = 0;
session.file_name = args.file_name;
session.chan = chan;
session.finished = 0;
/* get current digit detection mode, then disable digit detection if enabled */
{
int dummy = sizeof(restore_digit_detect);
ast_channel_queryoption(chan, AST_OPTION_DIGIT_DETECT, &restore_digit_detect, &dummy, 0);
}
if (restore_digit_detect) {
char new_digit_detect = 0;
ast_channel_setoption(chan, AST_OPTION_DIGIT_DETECT, &new_digit_detect, sizeof(new_digit_detect), 0);
}
/* disable FAX tone detection if enabled */
{
char new_fax_detect = 0;
ast_channel_setoption(chan, AST_OPTION_FAX_DETECT, &new_fax_detect, sizeof(new_fax_detect), 0);
}
res = transmit(&session);
if (restore_digit_detect) {
ast_channel_setoption(chan, AST_OPTION_DIGIT_DETECT, &restore_digit_detect, sizeof(restore_digit_detect), 0);
}
return res;
}
static int unload_module(void)
{
int res;
res = ast_unregister_application(app_sndfax_name);
res |= ast_unregister_application(app_rcvfax_name);
return res;
}
static int load_module(void)
{
int res ;
res = ast_register_application_xml(app_sndfax_name, sndfax_exec);
res |= ast_register_application_xml(app_rcvfax_name, rcvfax_exec);
/* The default SPAN message handler prints to stderr. It is something we do not want */
span_set_message_handler(NULL);
return res;
}
AST_MODULE_INFO(ASTERISK_GPL_KEY, AST_MODFLAG_DEFAULT, "Simple FAX Application",
.support_level = AST_MODULE_SUPPORT_DEPRECATED,
.load = load_module,
.unload = unload_module,
);