mirror of
https://github.com/eried/portapack-mayhem.git
synced 2024-12-30 17:56:33 -05:00
108 lines
2.6 KiB
C++
108 lines
2.6 KiB
C++
/*
|
|
* Copyright (C) 2014 Jared Boone, ShareBrained Technology, Inc.
|
|
* Copyright (C) 2018 Furrtek
|
|
*
|
|
* This file is part of PortaPack.
|
|
*
|
|
* 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, 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; see the file COPYING. If not, write to
|
|
* the Free Software Foundation, Inc., 51 Franklin Street,
|
|
* Boston, MA 02110-1301, USA.
|
|
*/
|
|
|
|
#include "acars_packet.hpp"
|
|
|
|
#include "crc.hpp"
|
|
|
|
#include <cstdlib>
|
|
|
|
namespace acars {
|
|
|
|
size_t Packet::length() const {
|
|
return packet_.size();
|
|
}
|
|
|
|
bool Packet::is_valid() const {
|
|
return true; //length_valid() && crc_ok();
|
|
}
|
|
|
|
Timestamp Packet::received_at() const {
|
|
return packet_.timestamp();
|
|
}
|
|
|
|
uint8_t Packet::block_id() const {
|
|
return field_.read(96, 8);
|
|
}
|
|
|
|
std::string Packet::registration_number() const {
|
|
std::string result;
|
|
result.reserve(7);
|
|
|
|
const size_t character_length = 8;
|
|
for(size_t i=16; i<(16+7*character_length); i+=character_length) {
|
|
result += (field_.read(i, character_length) & 0x7F);
|
|
}
|
|
|
|
return result;
|
|
}
|
|
|
|
uint32_t Packet::read(const size_t start_bit, const size_t length) const {
|
|
return field_.read(start_bit, length);
|
|
}
|
|
|
|
/*std::string Packet::text(
|
|
const size_t start_bit,
|
|
const size_t character_count
|
|
) const {
|
|
std::string result;
|
|
result.reserve(character_count);
|
|
|
|
const size_t character_length = 6;
|
|
const size_t end_bit = start_bit + character_count * character_length;
|
|
for(size_t i=start_bit; i<end_bit; i+=character_length) {
|
|
result += char_to_ascii(field_.read(i, character_length));
|
|
}
|
|
|
|
return result;
|
|
}*/
|
|
|
|
bool Packet::crc_ok() const {
|
|
CRCReader field_crc { packet_ };
|
|
CRC<16> acars_fcs { 0x1021, 0x0000, 0x0000 };
|
|
|
|
for(size_t i=0; i<data_length(); i+=8) {
|
|
acars_fcs.process_byte(field_crc.read(i, 8));
|
|
}
|
|
|
|
return (acars_fcs.checksum() == (unsigned)field_crc.read(data_length(), fcs_length));
|
|
}
|
|
|
|
size_t Packet::data_and_fcs_length() const {
|
|
return length() - 8;
|
|
}
|
|
|
|
size_t Packet::data_length() const {
|
|
return data_and_fcs_length() - fcs_length;
|
|
}
|
|
|
|
bool Packet::length_valid() const {
|
|
const size_t extra_bits = data_and_fcs_length() & 7;
|
|
if( extra_bits != 0 ) {
|
|
return false;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
} /* namespace ais */
|