| /* |
| * isdnhdlc.h -- General purpose ISDN HDLC decoder. |
| * |
| * Implementation of a HDLC decoder/encoder in software. |
| * Neccessary because some ISDN devices don't have HDLC |
| * controllers. Also included: a bit reversal table. |
| * |
| *Copyright (C) 2002 Wolfgang Mües <wolfgang@iksw-muees.de> |
| * 2001 Frode Isaksen <fisaksen@bewan.com> |
| * 2001 Kai Germaschewski <kai.germaschewski@gmx.de> |
| * |
| * This program is free software; you can redistribute it and/or modify |
| * it under the terms of the GNU General Public License as published by |
| * the Free Software Foundation; either version 2 of the License, or |
| * (at your option) any later version. |
| * |
| * 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 General Public License for more details. |
| * |
| * You should have received a copy of the GNU General Public License |
| * along with this program; if not, write to the Free Software |
| * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. |
| */ |
| |
| #ifndef __ISDNHDLC_H__ |
| #define __ISDNHDLC_H__ |
| |
| struct isdnhdlc_vars { |
| int bit_shift; |
| int hdlc_bits1; |
| int data_bits; |
| int ffbit_shift; // encoding only |
| int state; |
| int dstpos; |
| |
| unsigned short crc; |
| |
| unsigned char cbin; |
| unsigned char shift_reg; |
| unsigned char ffvalue; |
| |
| unsigned int data_received:1; // set if transferring data |
| unsigned int dchannel:1; // set if D channel (send idle instead of flags) |
| unsigned int do_adapt56:1; // set if 56K adaptation |
| unsigned int do_closing:1; // set if in closing phase (need to send CRC + flag |
| }; |
| |
| |
| /* |
| The return value from isdnhdlc_decode is |
| the frame length, 0 if no complete frame was decoded, |
| or a negative error number |
| */ |
| #define HDLC_FRAMING_ERROR 1 |
| #define HDLC_CRC_ERROR 2 |
| #define HDLC_LENGTH_ERROR 3 |
| |
| extern void isdnhdlc_rcv_init (struct isdnhdlc_vars *hdlc, int do_adapt56); |
| |
| extern int isdnhdlc_decode (struct isdnhdlc_vars *hdlc, const unsigned char *src, int slen,int *count, |
| unsigned char *dst, int dsize); |
| |
| extern void isdnhdlc_out_init (struct isdnhdlc_vars *hdlc,int is_d_channel,int do_adapt56); |
| |
| extern int isdnhdlc_encode (struct isdnhdlc_vars *hdlc,const unsigned char *src,unsigned short slen,int *count, |
| unsigned char *dst,int dsize); |
| |
| #endif /* __ISDNHDLC_H__ */ |