spandsp: t38_gateway.h Source File

spandsp 0.0.6

private/t38_gateway.h
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1/*
2 * SpanDSP - a series of DSP components for telephony
3 *
4 * private/t38_gateway.h - A T.38, less the packet exchange part
5 *
6 * Written by Steve Underwood <steveu@coppice.org>
7 *
8 * Copyright (C) 2005, 2006, 2007 Steve Underwood
9 *
10 * All rights reserved.
11 *
12 * This program is free software; you can redistribute it and/or modify
13 * it under the terms of the GNU Lesser General Public License version 2.1,
14 * as published by the Free Software Foundation.
15 *
16 * This program is distributed in the hope that it will be useful,
17 * but WITHOUT ANY WARRANTY; without even the implied warranty of
18 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
19 * GNU Lesser General Public License for more details.
20 *
21 * You should have received a copy of the GNU Lesser General Public
22 * License along with this program; if not, write to the Free Software
23 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
24 */
25
26/*! \file */
27
28#if !defined(_SPANDSP_PRIVATE_T38_GATEWAY_H_)
29#define _SPANDSP_PRIVATE_T38_GATEWAY_H_
30
31/*!
32 T.38 gateway T.38 side channel descriptor.
33*/
34 typedef struct
35{
36 /*! \brief Core T.38 IFP support */
37 t38_core_state_t t38;
38
39 /*! \brief TRUE if the NSF, NSC, and NSS are to be suppressed by altering
40 their contents to something the far end will not recognise. */
41 int suppress_nsx_len[2];
42 /*! \brief TRUE if we need to corrupt the HDLC frame in progress, so the receiver cannot
43 interpret it. The two values are for the two directions. */
44 int corrupt_current_frame[2];
45
46 /*! \brief the current class of field being received - i.e. none, non-ECM or HDLC */
47 int current_rx_field_class;
48 /*! \brief The T.38 indicator currently in use */
49 int in_progress_rx_indicator;
50
51 /*! \brief The current T.38 data type being sent. */
52 int current_tx_data_type;
53} t38_gateway_t38_state_t;
54
55/*!
56 T.38 gateway audio side channel descriptor.
57*/
58 typedef struct
59{
60 /*! \brief The FAX modem set for the audio side fo the gateway. */
61 fax_modems_state_t modems;
62 /*! \brief The current receive signal handler. Actual receiving hops between this
63 and a dummy receive routine. */
64 span_rx_handler_t *base_rx_handler;
65 span_rx_fillin_handler_t *base_rx_fillin_handler;
66} t38_gateway_audio_state_t;
67
68/*!
69 T.38 gateway T.38 side state.
70*/
71 typedef struct
72{
73 /*! \brief non-ECM and HDLC modem receive data buffer. */
74 uint8_t data[T38_RX_BUF_LEN];
75 /*! \brief Current pointer into the data buffer. */
76 int data_ptr;
77 /*! \brief The current octet being received as non-ECM data. */
78 unsigned int bit_stream;
79 /*! \brief The number of bits taken from the modem for the current scan row. This
80 is used during non-ECM transmission will fill bit removal to see that
81 T.38 packet transmissions do not stretch too far apart. */
82 int bits_absorbed;
83 /*! \brief The current bit number in the current non-ECM octet. */
84 int bit_no;
85 /*! \brief Progressively calculated CRC for HDLC messages received from a modem. */
86 uint16_t crc;
87 /*! \brief TRUE if non-ECM fill bits are to be stripped when sending image data. */
88 int fill_bit_removal;
89 /*! \brief The number of octets to send in each image packet (non-ECM or ECM) at the current
90 rate and the current specified packet interval. */
91 int octets_per_data_packet;
92
93 /*! \brief Bits into the non-ECM buffer */
94 int in_bits;
95 /*! \brief Octets fed out from the non-ECM buffer */
96 int out_octets;
97} t38_gateway_to_t38_state_t;
98
99/*!
100 T.38 gateway HDLC buffer.
101*/
102 typedef struct
103{
104 /*! \brief HDLC message buffers. */
105 uint8_t buf[T38_MAX_HDLC_LEN];
106 /*! \brief HDLC message lengths. */
107 int len;
108 /*! \brief HDLC message status flags. */
109 int flags;
110 /*! \brief HDLC buffer contents. */
111 int contents;
112} t38_gateway_hdlc_buf_t;
113
114/*!
115 T.38 gateway HDLC state.
116*/
117 typedef struct
118{
119 /*! \brief HDLC message buffers. */
120 t38_gateway_hdlc_buf_t buf[T38_TX_HDLC_BUFS];
121#if 0
122 /*! \brief HDLC message buffers. */
123 uint8_t buf[T38_TX_HDLC_BUFS][T38_MAX_HDLC_LEN];
124 /*! \brief HDLC message lengths. */
125 int len[T38_TX_HDLC_BUFS];
126 /*! \brief HDLC message status flags. */
127 int flags[T38_TX_HDLC_BUFS];
128 /*! \brief HDLC buffer contents. */
129 int contents[T38_TX_HDLC_BUFS];
130#endif
131 /*! \brief HDLC buffer number for input. */
132 int in;
133 /*! \brief HDLC buffer number for output. */
134 int out;
135} t38_gateway_hdlc_state_t;
136
137/*!
138 T.38 gateway core descriptor.
139*/
140 typedef struct
141{
142 /*! \brief A bit mask of the currently supported modem types. */
143 int supported_modems;
144 /*! \brief TRUE if ECM FAX mode is allowed through the gateway. */
145 int ecm_allowed;
146 /*! \brief Required time between T.38 transmissions, in ms. */
147 int ms_per_tx_chunk;
148
149 /*! \brief TRUE if in image data modem is to use short training. This usually
150 follows image_data_mode, but in ECM mode T.30 defines recovery
151 conditions in which long training is used for image data. */
152 int short_train;
153 /*! \brief TRUE if in image data mode, as opposed to TCF mode. */
154 int image_data_mode;
155 /*! \brief The minimum permitted bits per FAX scan line row. */
156 int min_row_bits;
157
158 /*! \brief TRUE if we should count the next MCF as a page end, else FALSE */
159 int count_page_on_mcf;
160 /*! \brief The number of pages for which a confirm (MCF) message was returned. */
161 int pages_confirmed;
162
163 /*! \brief TRUE if we are in error correcting (ECM) mode */
164 int ecm_mode;
165 /*! \brief The current bit rate for the fast modem. */
166 int fast_bit_rate;
167 /*! \brief The current fast receive modem type. */
168 int fast_rx_modem;
169 /*! \brief The type of fast receive modem currently active, which may be T38_NONE */
170 int fast_rx_active;
171
172 /*! \brief The current timed operation. */
173 int timed_mode;
174 /*! \brief The number of samples until the next timeout event */
175 int samples_to_timeout;
176
177 /*! Buffer for HDLC and non-ECM data going to the T.38 channel */
178 t38_gateway_to_t38_state_t to_t38;
179 /*! Buffer for data going to an HDLC modem. */
180 t38_gateway_hdlc_state_t hdlc_to_modem;
181 /*! Buffer for data going to a non-ECM mode modem. */
182 t38_non_ecm_buffer_state_t non_ecm_to_modem;
183
184 /*! \brief A pointer to a callback routine to be called when frames are
185 exchanged. */
186 t38_gateway_real_time_frame_handler_t *real_time_frame_handler;
187 /*! \brief An opaque pointer supplied in real time frame callbacks. */
188 void *real_time_frame_user_data;
189} t38_gateway_core_state_t;
190
191/*!
192 T.38 gateway state.
193*/
194 struct t38_gateway_state_s
195{
196 /*! T.38 side state */
197 t38_gateway_t38_state_t t38x;
198 /*! Audio side state */
199 t38_gateway_audio_state_t audio;
200 /*! T.38 core state */
201 t38_gateway_core_state_t core;
202
203 /*! \brief Error and flow logging control */
204 logging_state_t logging;
205};
206
207#endif
208/*- End of file ------------------------------------------------------------*/
fax_modems_state_s
Definition private/fax_modems.h:35
logging_state_s
Definition private/logging.h:34
t38_core_state_s
Definition private/t38_core.h:33
t38_gateway_audio_state_t
Definition private/t38_gateway.h:59
t38_gateway_audio_state_t::modems
fax_modems_state_t modems
The FAX modem set for the audio side fo the gateway.
Definition private/t38_gateway.h:61
t38_gateway_audio_state_t::base_rx_handler
span_rx_handler_t * base_rx_handler
The current receive signal handler. Actual receiving hops between this and a dummy receive routine.
Definition private/t38_gateway.h:64
t38_gateway_core_state_t
Definition private/t38_gateway.h:141
t38_gateway_core_state_t::real_time_frame_handler
t38_gateway_real_time_frame_handler_t * real_time_frame_handler
A pointer to a callback routine to be called when frames are exchanged.
Definition private/t38_gateway.h:186
t38_gateway_core_state_t::to_t38
t38_gateway_to_t38_state_t to_t38
Definition private/t38_gateway.h:178
t38_gateway_core_state_t::non_ecm_to_modem
t38_non_ecm_buffer_state_t non_ecm_to_modem
Definition private/t38_gateway.h:182
t38_gateway_core_state_t::timed_mode
int timed_mode
The current timed operation.
Definition private/t38_gateway.h:173
t38_gateway_core_state_t::hdlc_to_modem
t38_gateway_hdlc_state_t hdlc_to_modem
Definition private/t38_gateway.h:180
t38_gateway_core_state_t::ecm_mode
int ecm_mode
TRUE if we are in error correcting (ECM) mode.
Definition private/t38_gateway.h:164
t38_gateway_core_state_t::short_train
int short_train
TRUE if in image data modem is to use short training. This usually follows image_data_mode,...
Definition private/t38_gateway.h:152
t38_gateway_core_state_t::fast_bit_rate
int fast_bit_rate
The current bit rate for the fast modem.
Definition private/t38_gateway.h:166
t38_gateway_core_state_t::min_row_bits
int min_row_bits
The minimum permitted bits per FAX scan line row.
Definition private/t38_gateway.h:156
t38_gateway_core_state_t::count_page_on_mcf
int count_page_on_mcf
TRUE if we should count the next MCF as a page end, else FALSE.
Definition private/t38_gateway.h:159
t38_gateway_core_state_t::fast_rx_active
int fast_rx_active
The type of fast receive modem currently active, which may be T38_NONE.
Definition private/t38_gateway.h:170
t38_gateway_core_state_t::fast_rx_modem
int fast_rx_modem
The current fast receive modem type.
Definition private/t38_gateway.h:168
t38_gateway_core_state_t::real_time_frame_user_data
void * real_time_frame_user_data
An opaque pointer supplied in real time frame callbacks.
Definition private/t38_gateway.h:188
t38_gateway_core_state_t::samples_to_timeout
int samples_to_timeout
The number of samples until the next timeout event.
Definition private/t38_gateway.h:175
t38_gateway_core_state_t::pages_confirmed
int pages_confirmed
The number of pages for which a confirm (MCF) message was returned.
Definition private/t38_gateway.h:161
t38_gateway_core_state_t::ms_per_tx_chunk
int ms_per_tx_chunk
Required time between T.38 transmissions, in ms.
Definition private/t38_gateway.h:147
t38_gateway_core_state_t::image_data_mode
int image_data_mode
TRUE if in image data mode, as opposed to TCF mode.
Definition private/t38_gateway.h:154
t38_gateway_core_state_t::supported_modems
int supported_modems
A bit mask of the currently supported modem types.
Definition private/t38_gateway.h:143
t38_gateway_core_state_t::ecm_allowed
int ecm_allowed
TRUE if ECM FAX mode is allowed through the gateway.
Definition private/t38_gateway.h:145
t38_gateway_hdlc_buf_t
Definition private/t38_gateway.h:103
t38_gateway_hdlc_buf_t::contents
int contents
HDLC buffer contents.
Definition private/t38_gateway.h:111
t38_gateway_hdlc_buf_t::len
int len
HDLC message lengths.
Definition private/t38_gateway.h:107
t38_gateway_hdlc_buf_t::flags
int flags
HDLC message status flags.
Definition private/t38_gateway.h:109
t38_gateway_hdlc_state_t
Definition private/t38_gateway.h:118
t38_gateway_hdlc_state_t::in
int in
HDLC buffer number for input.
Definition private/t38_gateway.h:132
t38_gateway_hdlc_state_t::out
int out
HDLC buffer number for output.
Definition private/t38_gateway.h:134
t38_gateway_state_s
Definition private/t38_gateway.h:195
t38_gateway_state_s::t38x
t38_gateway_t38_state_t t38x
Definition private/t38_gateway.h:197
t38_gateway_state_s::logging
logging_state_t logging
Error and flow logging control.
Definition private/t38_gateway.h:204
t38_gateway_state_s::core
t38_gateway_core_state_t core
Definition private/t38_gateway.h:201
t38_gateway_state_s::audio
t38_gateway_audio_state_t audio
Definition private/t38_gateway.h:199
t38_gateway_t38_state_t
Definition private/t38_gateway.h:35
t38_gateway_t38_state_t::in_progress_rx_indicator
int in_progress_rx_indicator
The T.38 indicator currently in use.
Definition private/t38_gateway.h:49
t38_gateway_t38_state_t::current_tx_data_type
int current_tx_data_type
The current T.38 data type being sent.
Definition private/t38_gateway.h:52
t38_gateway_t38_state_t::current_rx_field_class
int current_rx_field_class
the current class of field being received - i.e. none, non-ECM or HDLC
Definition private/t38_gateway.h:47
t38_gateway_t38_state_t::t38
t38_core_state_t t38
Core T.38 IFP support.
Definition private/t38_gateway.h:37
t38_gateway_to_t38_state_t
Definition private/t38_gateway.h:72
t38_gateway_to_t38_state_t::in_bits
int in_bits
Bits into the non-ECM buffer.
Definition private/t38_gateway.h:94
t38_gateway_to_t38_state_t::fill_bit_removal
int fill_bit_removal
TRUE if non-ECM fill bits are to be stripped when sending image data.
Definition private/t38_gateway.h:88
t38_gateway_to_t38_state_t::bit_no
int bit_no
The current bit number in the current non-ECM octet.
Definition private/t38_gateway.h:84
t38_gateway_to_t38_state_t::crc
uint16_t crc
Progressively calculated CRC for HDLC messages received from a modem.
Definition private/t38_gateway.h:86
t38_gateway_to_t38_state_t::data_ptr
int data_ptr
Current pointer into the data buffer.
Definition private/t38_gateway.h:76
t38_gateway_to_t38_state_t::out_octets
int out_octets
Octets fed out from the non-ECM buffer.
Definition private/t38_gateway.h:96
t38_gateway_to_t38_state_t::bits_absorbed
int bits_absorbed
The number of bits taken from the modem for the current scan row. This is used during non-ECM transmi...
Definition private/t38_gateway.h:82
t38_gateway_to_t38_state_t::bit_stream
unsigned int bit_stream
The current octet being received as non-ECM data.
Definition private/t38_gateway.h:78
t38_gateway_to_t38_state_t::octets_per_data_packet
int octets_per_data_packet
The number of octets to send in each image packet (non-ECM or ECM) at the current rate and the curren...
Definition private/t38_gateway.h:91
t38_non_ecm_buffer_state_s
A flow controlled non-ECM image data buffer, for buffering T.38 to analogue modem data.
Definition private/t38_non_ecm_buffer.h:34
t38_gateway_real_time_frame_handler_t
void() t38_gateway_real_time_frame_handler_t(t38_gateway_state_t *s, void *user_data, int direction, const uint8_t *msg, int len)
T.30 real time frame handler.
Definition t38_gateway.h:59
T38_TX_HDLC_BUFS
#define T38_TX_HDLC_BUFS
Definition t38_gateway.h:44
T38_MAX_HDLC_LEN
#define T38_MAX_HDLC_LEN
Definition t38_gateway.h:46