MMDVMHost-Private/DMRDataHeader.cpp
2016-02-29 06:37:27 +00:00

206 lines
4.7 KiB
C++

/*
* Copyright (C) 2012 by Ian Wraith
* Copyright (C) 2015,2016 by Jonathan Naylor G4KLX
*
* 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.
*/
#include "DMRDataHeader.h"
#include "DMRDefines.h"
#include "BPTC19696.h"
#include "RS129.h"
#include "Utils.h"
#include "CRC.h"
#include "Log.h"
#include <cstdio>
#include <cassert>
#include <cstring>
CDMRDataHeader::CDMRDataHeader() :
m_data(NULL),
m_GI(false),
m_A(false),
m_srcId(0U),
m_dstId(0U),
m_blocks(0U),
m_F(false),
m_S(false),
m_Ns(0U)
{
m_data = new unsigned char[12U];
}
CDMRDataHeader::~CDMRDataHeader()
{
delete[] m_data;
}
bool CDMRDataHeader::put(const unsigned char* bytes)
{
assert(bytes != NULL);
CBPTC19696 bptc;
bptc.decode(bytes, m_data);
m_data[10U] ^= DATA_HEADER_CRC_MASK[0U];
m_data[11U] ^= DATA_HEADER_CRC_MASK[1U];
bool valid = CCRC::checkCCITT162(m_data, 12U);
if (!valid)
return false;
// Restore the checksum
m_data[10U] ^= DATA_HEADER_CRC_MASK[0U];
m_data[11U] ^= DATA_HEADER_CRC_MASK[1U];
m_GI = (m_data[0U] & 0x80U) == 0x80U;
m_A = (m_data[0U] & 0x40U) == 0x40U;
unsigned char dpf = m_data[0U] & 0x0FU;
if (dpf == DPF_PROPRIETARY)
return true;
m_dstId = m_data[2U] << 16 | m_data[3U] << 8 | m_data[4U];
m_srcId = m_data[5U] << 16 | m_data[6U] << 8 | m_data[7U];
switch (dpf) {
case DPF_UNCONFIRMED_DATA:
CUtils::dump("Unconfirmed Data Header", m_data, 12U);
m_F = (m_data[8U] & 0x80U) == 0x80U;
m_blocks = m_data[8U] & 0x7FU;
break;
case DPF_CONFIRMED_DATA:
CUtils::dump("Confirmed Data Header", m_data, 12U);
m_F = (m_data[8U] & 0x80U) == 0x80U;
m_blocks = m_data[8U] & 0x7FU;
m_S = (m_data[9U] & 0x80U) == 0x80U;
m_Ns = (m_data[9U] >> 4) & 0x07U;
break;
case DPF_RESPONSE:
CUtils::dump("Response Data Header", m_data, 12U);
m_blocks = m_data[8U] & 0x7FU;
break;
case DPF_PROPRIETARY:
CUtils::dump("Proprietary Data Header", m_data, 12U);
break;
case DPF_DEFINED_RAW:
CUtils::dump("Raw or Status/Precoded Short Data Header", m_data, 12U);
m_F = (m_data[8U] & 0x01U) == 0x01U;
m_S = (m_data[8U] & 0x02U) == 0x02U;
break;
case DPF_DEFINED_SHORT:
CUtils::dump("Defined Short Data Header", m_data, 12U);
m_F = (m_data[8U] & 0x01U) == 0x01U;
m_S = (m_data[8U] & 0x02U) == 0x02U;
break;
case DPF_UDT:
CUtils::dump("Unified Data Transport Header", m_data, 12U);
break;
default:
CUtils::dump("Unknown Data Header", m_data, 12U);
break;
}
return true;
}
void CDMRDataHeader::get(unsigned char* bytes) const
{
assert(bytes != NULL);
CBPTC19696 bptc;
bptc.encode(m_data, bytes);
}
bool CDMRDataHeader::getGI() const
{
return m_GI;
}
unsigned int CDMRDataHeader::getSrcId() const
{
return m_srcId;
}
unsigned int CDMRDataHeader::getDstId() const
{
return m_dstId;
}
unsigned int CDMRDataHeader::getBlocks() const
{
return m_blocks;
}
void CDMRDataHeader::getTerminator(unsigned char* bytes) const
{
assert(bytes != NULL);
unsigned char payload[12U];
::memset(payload, 0x00U, 12U);
payload[0U] = m_GI ? FLCO_GROUP : FLCO_USER_USER;
payload[1U] = FID_ETSI;
payload[2U] = (m_dstId >> 16) & 0xFFU;
payload[3U] = (m_dstId >> 8) & 0xFFU;
payload[4U] = (m_dstId >> 0) & 0xFFU;
payload[5U] = (m_srcId >> 16) & 0xFFU;
payload[6U] = (m_srcId >> 8) & 0xFFU;
payload[7U] = (m_srcId >> 0) & 0xFFU;
payload[8U] |= m_GI ? 0x80U : 0x00U;
payload[8U] |= m_A ? 0x40U : 0x00U;
payload[8U] |= m_F ? 0x20U : 0x00U;
payload[8U] |= m_S ? 0x08U : 0x00U;
payload[8U] |= m_Ns & 0x07U;
unsigned char parity[4U];
CRS129::encode(payload, 9U, parity);
payload[9U] = parity[2U] ^ TERMINATOR_WITH_LC_CRC_MASK[0U];
payload[10U] = parity[1U] ^ TERMINATOR_WITH_LC_CRC_MASK[1U];
payload[11U] = parity[0U] ^ TERMINATOR_WITH_LC_CRC_MASK[2U];
CBPTC19696 bptc;
bptc.encode(payload, bytes);
}
CDMRDataHeader& CDMRDataHeader::operator=(const CDMRDataHeader& header)
{
if (&header != this) {
::memcpy(m_data, header.m_data, 12U);
m_GI = header.m_GI;
m_A = header.m_A;
m_srcId = header.m_srcId;
m_dstId = header.m_dstId;
m_blocks = header.m_blocks;
m_F = header.m_F;
m_S = header.m_S;
m_Ns = header.m_Ns;
}
return *this;
}