208 lines
6.8 KiB
C
208 lines
6.8 KiB
C
/*
|
|
* SpanDSP - a series of DSP components for telephony
|
|
*
|
|
* private/t38_gateway.h - A T.38, less the packet exchange part
|
|
*
|
|
* Written by Steve Underwood <steveu@coppice.org>
|
|
*
|
|
* Copyright (C) 2005, 2006, 2007 Steve Underwood
|
|
*
|
|
* All rights reserved.
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU Lesser General Public License version 2.1,
|
|
* as published by the Free Software Foundation.
|
|
*
|
|
* This program is distributed in the hope that it will be useful,
|
|
* but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
* GNU Lesser General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU Lesser General Public
|
|
* License along with this program; if not, write to the Free Software
|
|
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
|
|
*
|
|
* $Id: t38_gateway.h,v 1.5 2009/11/07 08:58:58 steveu Exp $
|
|
*/
|
|
|
|
/*! \file */
|
|
|
|
#if !defined(_SPANDSP_PRIVATE_T38_GATEWAY_H_)
|
|
#define _SPANDSP_PRIVATE_T38_GATEWAY_H_
|
|
|
|
/*!
|
|
T.38 gateway T.38 side channel descriptor.
|
|
*/
|
|
typedef struct
|
|
{
|
|
/*! Core T.38 IFP support */
|
|
t38_core_state_t t38;
|
|
|
|
/*! \brief TRUE if the NSF, NSC, and NSS are to be suppressed by altering
|
|
their contents to something the far end will not recognise. */
|
|
int suppress_nsx_len[2];
|
|
/*! \brief TRUE if we need to corrupt the HDLC frame in progress, so the receiver cannot
|
|
interpret it. The two values are for the two directions. */
|
|
int corrupt_current_frame[2];
|
|
|
|
/*! \brief the current class of field being received - i.e. none, non-ECM or HDLC */
|
|
int current_rx_field_class;
|
|
/*! \brief The T.38 indicator currently in use */
|
|
int in_progress_rx_indicator;
|
|
|
|
/*! \brief The current T.38 data type being sent. */
|
|
int current_tx_data_type;
|
|
} t38_gateway_t38_state_t;
|
|
|
|
/*!
|
|
T.38 gateway audio side channel descriptor.
|
|
*/
|
|
typedef struct
|
|
{
|
|
/*! \brief The FAX modem set for the audio side fo the gateway. */
|
|
fax_modems_state_t modems;
|
|
/*! \brief The current receive signal handler. Actual receiving hop between this
|
|
and a dummy receive routine. */
|
|
span_rx_handler_t *base_rx_handler;
|
|
} t38_gateway_audio_state_t;
|
|
|
|
/*!
|
|
T.38 gateway T.38 side state.
|
|
*/
|
|
typedef struct
|
|
{
|
|
/*! \brief non-ECM and HDLC modem receive data buffer. */
|
|
uint8_t data[T38_RX_BUF_LEN];
|
|
/*! \brief Current pointer into the data buffer. */
|
|
int data_ptr;
|
|
/*! \brief The current octet being received as non-ECM data. */
|
|
unsigned int bit_stream;
|
|
/*! \brief The number of bits taken from the modem for the current scan row. This
|
|
is used during non-ECM transmission will fill bit removal to see that
|
|
T.38 packet transmissions do not stretch too far apart. */
|
|
int bits_absorbed;
|
|
/*! \brief The current bit number in the current non-ECM octet. */
|
|
int bit_no;
|
|
/*! \brief Progressively calculated CRC for HDLC messages received from a modem. */
|
|
uint16_t crc;
|
|
/*! \brief TRUE if non-ECM fill bits are to be stripped when sending image data. */
|
|
int fill_bit_removal;
|
|
/*! \brief The number of octets to send in each image packet (non-ECM or ECM) at the current
|
|
rate and the current specified packet interval. */
|
|
int octets_per_data_packet;
|
|
|
|
/*! \brief Bits into the non-ECM buffer */
|
|
int in_bits;
|
|
/*! \brief Octets fed out from the non-ECM buffer */
|
|
int out_octets;
|
|
} t38_gateway_to_t38_state_t;
|
|
|
|
/*!
|
|
T.38 gateway HDLC buffer.
|
|
*/
|
|
typedef struct
|
|
{
|
|
/*! \brief HDLC message buffers. */
|
|
uint8_t buf[T38_MAX_HDLC_LEN];
|
|
/*! \brief HDLC message lengths. */
|
|
int len;
|
|
/*! \brief HDLC message status flags. */
|
|
int flags;
|
|
/*! \brief HDLC buffer contents. */
|
|
int contents;
|
|
} t38_gateway_hdlc_buf_t;
|
|
|
|
/*!
|
|
T.38 gateway HDLC state.
|
|
*/
|
|
typedef struct
|
|
{
|
|
/*! \brief HDLC message buffers. */
|
|
t38_gateway_hdlc_buf_t buf[T38_TX_HDLC_BUFS];
|
|
#if 0
|
|
/*! \brief HDLC message buffers. */
|
|
uint8_t buf[T38_TX_HDLC_BUFS][T38_MAX_HDLC_LEN];
|
|
/*! \brief HDLC message lengths. */
|
|
int len[T38_TX_HDLC_BUFS];
|
|
/*! \brief HDLC message status flags. */
|
|
int flags[T38_TX_HDLC_BUFS];
|
|
/*! \brief HDLC buffer contents. */
|
|
int contents[T38_TX_HDLC_BUFS];
|
|
#endif
|
|
/*! \brief HDLC buffer number for input. */
|
|
int in;
|
|
/*! \brief HDLC buffer number for output. */
|
|
int out;
|
|
} t38_gateway_hdlc_state_t;
|
|
|
|
/*!
|
|
T.38 gateway core descriptor.
|
|
*/
|
|
typedef struct
|
|
{
|
|
/*! \brief A bit mask of the currently supported modem types. */
|
|
int supported_modems;
|
|
/*! \brief TRUE if ECM FAX mode is allowed through the gateway. */
|
|
int ecm_allowed;
|
|
|
|
/*! \brief TRUE if in image data modem is to use short training. This usually
|
|
follows image_data_mode, but in ECM mode T.30 defines recovery
|
|
conditions in which long training is used for image data. */
|
|
int short_train;
|
|
/*! \brief TRUE if in image data mode, as opposed to TCF mode. */
|
|
int image_data_mode;
|
|
/*! \brief The minimum permitted bits per FAX scan line row. */
|
|
int min_row_bits;
|
|
|
|
/*! \brief TRUE if we should count the next MCF as a page end, else FALSE */
|
|
int count_page_on_mcf;
|
|
/*! \brief The number of pages for which a confirm (MCF) message was returned. */
|
|
int pages_confirmed;
|
|
|
|
/*! \brief TRUE if we are in error correcting (ECM) mode */
|
|
int ecm_mode;
|
|
/*! \brief The current bit rate for the fast modem. */
|
|
int fast_bit_rate;
|
|
/*! \brief The current fast receive modem type. */
|
|
int fast_rx_modem;
|
|
/*! \brief The type of fast receive modem currently active, which may be T38_NONE */
|
|
int fast_rx_active;
|
|
|
|
/*! \brief The current timed operation. */
|
|
int timed_mode;
|
|
/*! \brief The number of samples until the next timeout event */
|
|
int samples_to_timeout;
|
|
|
|
/*! Buffer for HDLC and non-ECM data going to the T.38 channel */
|
|
t38_gateway_to_t38_state_t to_t38;
|
|
/*! Buffer for data going to an HDLC modem. */
|
|
t38_gateway_hdlc_state_t hdlc_to_modem;
|
|
/*! Buffer for data going to a non-ECM mode modem. */
|
|
t38_non_ecm_buffer_state_t non_ecm_to_modem;
|
|
|
|
/*! \brief A pointer to a callback routine to be called when frames are
|
|
exchanged. */
|
|
t38_gateway_real_time_frame_handler_t *real_time_frame_handler;
|
|
/*! \brief An opaque pointer supplied in real time frame callbacks. */
|
|
void *real_time_frame_user_data;
|
|
} t38_gateway_core_state_t;
|
|
|
|
/*!
|
|
T.38 gateway state.
|
|
*/
|
|
struct t38_gateway_state_s
|
|
{
|
|
/*! T.38 side state */
|
|
t38_gateway_t38_state_t t38x;
|
|
/*! Audio side state */
|
|
t38_gateway_audio_state_t audio;
|
|
/*! T.38 core state */
|
|
t38_gateway_core_state_t core;
|
|
|
|
/*! \brief Error and flow logging control */
|
|
logging_state_t logging;
|
|
};
|
|
|
|
#endif
|
|
/*- End of file ------------------------------------------------------------*/
|