libosmocore 1.13.1.1-afb4 Osmocom core library

isdnhdlc.h
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1/*
2 * isdnhdlc.h -- General purpose ISDN HDLC decoder.
3 *
4 * Implementation of a HDLC decoder/encoder in software.
5 * Necessary because some ISDN devices don't have HDLC
6 * controllers.
7 *
8 * Copyright (C)
9 * 2009 Karsten Keil <keil@b1-systems.de>
10 * 2002 Wolfgang Mües <wolfgang@iksw-muees.de>
11 * 2001 Frode Isaksen <fisaksen@bewan.com>
12 * 2001 Kai Germaschewski <kai.germaschewski@gmx.de>
13 *
14 * This program is free software; you can redistribute it and/or modify
15 * it under the terms of the GNU General Public License as published by
16 * the Free Software Foundation; either version 2 of the License, or
17 * (at your option) any later version.
18 *
19 * This program is distributed in the hope that it will be useful,
20 * but WITHOUT ANY WARRANTY; without even the implied warranty of
21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
22 * GNU General Public License for more details.
23 */
24
25#pragma once
26
27#include <stdint.h>
28
29 struct osmo_isdnhdlc_vars {
30 int bit_shift;
31 int hdlc_bits1;
32 int data_bits;
33 int ffbit_shift; /* encoding only */
34 int state;
35 int dstpos;
36
37 uint16_t crc;
38
39 uint8_t cbin;
40 uint8_t shift_reg;
41 uint8_t ffvalue;
42
43 /* set if transferring data */
44 uint32_t data_received:1;
45 /* set if D channel (send idle instead of flags) */
46 uint32_t dchannel:1;
47 /* set if 56K adaptation */
48 uint32_t do_adapt56:1;
49 /* set if in closing phase (need to send CRC + flag) */
50 uint32_t do_closing:1;
51 /* set if data is bitreverse */
52 uint32_t do_bitreverse:1;
53};
54
55/* Feature Flags */
56#define OSMO_HDLC_F_56KBIT 0x01
57#define OSMO_HDLC_F_DCHANNEL 0x02
58#define OSMO_HDLC_F_BITREVERSE 0x04
59
60/*
61 The return value from isdnhdlc_decode is
62 the frame length, 0 if no complete frame was decoded,
63 or a negative error number
64*/
65#define OSMO_HDLC_FRAMING_ERROR 1
66#define OSMO_HDLC_CRC_ERROR 2
67#define OSMO_HDLC_LENGTH_ERROR 3
68
69 extern void osmo_isdnhdlc_rcv_init(struct osmo_isdnhdlc_vars *hdlc, uint32_t features);
70
71 extern int osmo_isdnhdlc_decode(struct osmo_isdnhdlc_vars *hdlc, const uint8_t *src,
72 int slen, int *count, uint8_t *dst, int dsize);
73
74 extern void osmo_isdnhdlc_out_init(struct osmo_isdnhdlc_vars *hdlc, uint32_t features);
75
76 extern int osmo_isdnhdlc_encode(struct osmo_isdnhdlc_vars *hdlc, const uint8_t *src,
77 uint16_t slen, int *count, uint8_t *dst, int dsize);
osmo_isdnhdlc_encode
int osmo_isdnhdlc_encode(struct osmo_isdnhdlc_vars *hdlc, const uint8_t *src, uint16_t slen, int *count, uint8_t *dst, int dsize)
encodes HDLC frames to a transparent bit stream.
Definition: isdnhdlc.c:338
osmo_isdnhdlc_decode
int osmo_isdnhdlc_decode(struct osmo_isdnhdlc_vars *hdlc, const uint8_t *src, int slen, int *count, uint8_t *dst, int dsize)
decodes HDLC frames from a transparent bit stream.
Definition: isdnhdlc.c:117
osmo_isdnhdlc_rcv_init
void osmo_isdnhdlc_rcv_init(struct osmo_isdnhdlc_vars *hdlc, uint32_t features)
Definition: isdnhdlc.c:44
osmo_isdnhdlc_out_init
void osmo_isdnhdlc_out_init(struct osmo_isdnhdlc_vars *hdlc, uint32_t features)
Definition: isdnhdlc.c:54
osmo_isdnhdlc_vars
Definition: isdnhdlc.h:29
osmo_isdnhdlc_vars::do_adapt56
uint32_t do_adapt56
Definition: isdnhdlc.h:48
osmo_isdnhdlc_vars::crc
uint16_t crc
Definition: isdnhdlc.h:37
osmo_isdnhdlc_vars::hdlc_bits1
int hdlc_bits1
Definition: isdnhdlc.h:31
osmo_isdnhdlc_vars::dstpos
int dstpos
Definition: isdnhdlc.h:35
osmo_isdnhdlc_vars::ffbit_shift
int ffbit_shift
Definition: isdnhdlc.h:33
osmo_isdnhdlc_vars::data_received
uint32_t data_received
Definition: isdnhdlc.h:44
osmo_isdnhdlc_vars::do_closing
uint32_t do_closing
Definition: isdnhdlc.h:50
osmo_isdnhdlc_vars::cbin
uint8_t cbin
Definition: isdnhdlc.h:39
osmo_isdnhdlc_vars::ffvalue
uint8_t ffvalue
Definition: isdnhdlc.h:41
osmo_isdnhdlc_vars::shift_reg
uint8_t shift_reg
Definition: isdnhdlc.h:40
osmo_isdnhdlc_vars::bit_shift
int bit_shift
Definition: isdnhdlc.h:30
osmo_isdnhdlc_vars::dchannel
uint32_t dchannel
Definition: isdnhdlc.h:46
osmo_isdnhdlc_vars::do_bitreverse
uint32_t do_bitreverse
Definition: isdnhdlc.h:52
osmo_isdnhdlc_vars::state
int state
Definition: isdnhdlc.h:34
osmo_isdnhdlc_vars::data_bits
int data_bits
Definition: isdnhdlc.h:32