MMDVMHost-Private/FullLC.cpp

102 lines
2.6 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 "FullLC.h"
#include "Log.h"
#include "DMRDefines.h"
#include "RS129.h"
#include <cstdio>
#include <cassert>
CFullLC::CFullLC() :
m_bptc()
{
}
CFullLC::~CFullLC()
{
}
CLC* CFullLC::decode(const unsigned char* data, unsigned char type)
{
assert(data != NULL);
unsigned char lcData[12U];
m_bptc.decode(data, lcData);
switch (type) {
case DT_VOICE_LC_HEADER:
lcData[9U] ^= VOICE_LC_HEADER_CRC_MASK[0U];
lcData[10U] ^= VOICE_LC_HEADER_CRC_MASK[1U];
lcData[11U] ^= VOICE_LC_HEADER_CRC_MASK[2U];
break;
case DT_TERMINATOR_WITH_LC:
lcData[9U] ^= TERMINATOR_WITH_LC_CRC_MASK[0U];
lcData[10U] ^= TERMINATOR_WITH_LC_CRC_MASK[1U];
lcData[11U] ^= TERMINATOR_WITH_LC_CRC_MASK[2U];
break;
default:
::LogError("Unsupported LC type - %d", int(type));
return NULL;
}
if (!CRS129::check(lcData)) {
::LogDebug("Checksum failed for the LC");
CLC lc(lcData);
LogDebug("Invalid LC, src = %u, dst = %s%u", lc.getSrcId(), lc.getFLCO() == FLCO_GROUP ? "TG " : "", lc.getDstId());
return NULL;
}
return new CLC(lcData);
}
void CFullLC::encode(const CLC& lc, unsigned char* data, unsigned char type)
{
assert(data != NULL);
unsigned char lcData[12U];
lc.getData(lcData);
unsigned char parity[4U];
CRS129::encode(lcData, 9U, parity);
switch (type) {
case DT_VOICE_LC_HEADER:
lcData[9U] = parity[2U] ^ VOICE_LC_HEADER_CRC_MASK[0U];
lcData[10U] = parity[1U] ^ VOICE_LC_HEADER_CRC_MASK[1U];
lcData[11U] = parity[0U] ^ VOICE_LC_HEADER_CRC_MASK[2U];
break;
case DT_TERMINATOR_WITH_LC:
lcData[9U] = parity[2U] ^ TERMINATOR_WITH_LC_CRC_MASK[0U];
lcData[10U] = parity[1U] ^ TERMINATOR_WITH_LC_CRC_MASK[1U];
lcData[11U] = parity[0U] ^ TERMINATOR_WITH_LC_CRC_MASK[2U];
break;
default:
::LogError("Unsupported LC type - %d", int(type));
return;
}
m_bptc.encode(lcData, data);
}