mirror of
https://github.com/eried/portapack-mayhem.git
synced 2024-12-27 00:09:36 -05:00
50bab791dd
The underlying function used for calculating Latitude and Longitude -also used in other places inside the radiosonde app- was returning a positive value always. But it needs to cope with negative values also (i.e. Lat and Lon) Fixed by just changing the returning value into int32_t (even if the calculation is done in uint32_t, the actual sign is passed thru when returning the calculated value -those are the same 4 bytes, interpreted either as (before) unsigned or (now) signed)
66 lines
1.8 KiB
C++
66 lines
1.8 KiB
C++
/*
|
|
* Copyright (C) 2015 Jared Boone, ShareBrained Technology, Inc.
|
|
*
|
|
* 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.
|
|
*/
|
|
|
|
#ifndef __FIELD_READER_H__
|
|
#define __FIELD_READER_H__
|
|
|
|
#include <cstdint>
|
|
#include <cstddef>
|
|
|
|
struct BitRemapNone {
|
|
constexpr size_t operator()(const size_t& bit_index) const {
|
|
return bit_index;
|
|
}
|
|
};
|
|
|
|
struct BitRemapByteReverse {
|
|
constexpr size_t operator()(const size_t bit_index) const {
|
|
return bit_index ^ 7;
|
|
}
|
|
};
|
|
|
|
template<typename T, typename BitRemap>
|
|
class FieldReader {
|
|
public:
|
|
constexpr FieldReader(
|
|
const T& data
|
|
) : data { data }
|
|
{
|
|
}
|
|
|
|
/* The "start_bit" winds up being the MSB of the returned field value. */
|
|
/* The BitRemap functor determines which bits are read from the source
|
|
* packet. */
|
|
int32_t read(const size_t start_bit, const size_t length) const { //Euquiq: was uint32_t, used for calculating lat / lon in radiosondes, can be negative too
|
|
uint32_t value = 0;
|
|
for(size_t i=start_bit; i<(start_bit + length); i++) {
|
|
value = (value << 1) | data[bit_remap(i)];
|
|
}
|
|
return value;
|
|
}
|
|
|
|
private:
|
|
const T& data;
|
|
const BitRemap bit_remap { };
|
|
};
|
|
|
|
#endif/*__FIELD_READER_H__*/
|