You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
98 lines
2.8 KiB
98 lines
2.8 KiB
// SPDX-License-Identifier: GPL-2.0-only
|
|
/*
|
|
* Digital Voice Modem - Common Library
|
|
* GPLv2 Open Source. Use is subject to license terms.
|
|
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
|
|
*
|
|
* Copyright (C) 2024-2025 Bryan Biedenkapp, N2PLL
|
|
*
|
|
*/
|
|
#include "common/p25/dfsi/frames/BlockHeader.h"
|
|
#include "common/p25/dfsi/DFSIDefines.h"
|
|
#include "common/Utils.h"
|
|
#include "common/Log.h"
|
|
|
|
#include <cassert>
|
|
#include <cstring>
|
|
|
|
using namespace p25;
|
|
using namespace p25::dfsi;
|
|
using namespace p25::dfsi::frames;
|
|
|
|
// ---------------------------------------------------------------------------
|
|
// Public Class Members
|
|
// ---------------------------------------------------------------------------
|
|
|
|
/* Initializes a instance of the BlockHeader class. */
|
|
|
|
BlockHeader::BlockHeader() :
|
|
m_payloadType(true),
|
|
m_blockType(BlockType::UNDEFINED),
|
|
m_timestampOffset(0U),
|
|
m_blockLength(0U)
|
|
{
|
|
/* stub */
|
|
}
|
|
|
|
/* Initializes a instance of the BlockHeader class. */
|
|
|
|
BlockHeader::BlockHeader(uint8_t* data, bool verbose) :
|
|
m_payloadType(true),
|
|
m_blockType(BlockType::UNDEFINED),
|
|
m_timestampOffset(0U),
|
|
m_blockLength(0U)
|
|
{
|
|
decode(data, verbose);
|
|
}
|
|
|
|
/* Decode a block header frame. */
|
|
|
|
bool BlockHeader::decode(const uint8_t* data, bool verbose)
|
|
{
|
|
assert(data != nullptr);
|
|
|
|
uint64_t value = 0U;
|
|
|
|
// combine bytes into ulong (8 byte) value
|
|
value = data[0U];
|
|
value = (value << 8) + data[1U];
|
|
value = (value << 8) + data[2U];
|
|
value = (value << 8) + data[3U];
|
|
|
|
m_payloadType = (data[0U] & 0x80U) == 0x80U; // Payload Type
|
|
m_blockType = (BlockType::E)(data[0U] & 0x7FU); // Block Type
|
|
|
|
if (verbose) {
|
|
m_timestampOffset = (uint32_t)((value >> 10) & 0x3FFU); // Timestamp Offset
|
|
m_blockLength = (uint32_t)(value & 0x3FFU); // Block Length
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
/* Encode a block header frame. */
|
|
|
|
void BlockHeader::encode(uint8_t* data, bool verbose)
|
|
{
|
|
assert(data != nullptr);
|
|
|
|
if (!verbose) {
|
|
data[0U] = (uint8_t)((m_payloadType ? 0x80U : 0x00U) + // Payload Type
|
|
((uint8_t)m_blockType & 0x7FU)); // Block Type
|
|
}
|
|
else {
|
|
uint64_t value = 0;
|
|
|
|
value = (uint8_t)((m_payloadType ? 0x80U : 0x00U) + // Payload Type
|
|
((uint8_t)m_blockType & 0x7FU)); // Block Type
|
|
value = (value << 24) + (m_timestampOffset & 0x3FFU); // Timestamp Offset
|
|
value = (value << 10) + (m_blockLength & 0x3FFU); // Block Length
|
|
|
|
// split ulong (8 byte) value into bytes
|
|
data[0U] = (uint8_t)((value >> 24) & 0xFFU);
|
|
data[1U] = (uint8_t)((value >> 16) & 0xFFU);
|
|
data[2U] = (uint8_t)((value >> 8) & 0xFFU);
|
|
data[3U] = (uint8_t)((value >> 0) & 0xFFU);
|
|
}
|
|
}
|