utils.h

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/* -*- c++ -*- */
/*
 * gr-satnogs: SatNOGS GNU Radio Out-Of-Tree Module
 *
 *  Copyright (C) 2016,2018,2019,2022 Libre Space Foundation <http://libre.space/>
 *
 *  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 3 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, see <http://www.gnu.org/licenses/>.
 */
 
#ifndef INCLUDE_SATNOGS_UTILS_H_
#define INCLUDE_SATNOGS_UTILS_H_
 
#include <arpa/inet.h>
#include <itpp/itbase.h>
#include <cmath>
#include <cstdint>
#include <cstdlib>
 
template <class T, class U, bool S>
class utils_helper
{
public:
    static size_t packed_to_unpacked(T out, const U in, size_t len) { return 0; }
 
    static size_t unpacked_to_packed(U out, const T in, size_t len) { return 0; }
};
 
template <>
class utils_helper<uint8_t*, uint8_t*, false>
{
public:
    static size_t packed_to_unpacked(uint8_t* out, const uint8_t* in, size_t len)
    {
        if (!out || !in || !len) {
            return 0;
        }
 
        for (size_t i = 0; i < len; i++) {
            *out++ = (in[i] >> 7) & 0x1;
            *out++ = (in[i] >> 6) & 0x1;
            *out++ = (in[i] >> 5) & 0x1;
            *out++ = (in[i] >> 4) & 0x1;
            *out++ = (in[i] >> 3) & 0x1;
            *out++ = (in[i] >> 2) & 0x1;
            *out++ = (in[i] >> 1) & 0x1;
            *out++ = in[i] & 0x1;
        }
 
        return len * 8;
    }
 
    static size_t unpacked_to_packed(uint8_t* out, const uint8_t* in, size_t len)
    {
        if (!out || !in || !len) {
            return 0;
        }
 
        struct h {
            uint8_t shift : 3;
        } x = { .shift = 7 };
 
        memset(out, 0, static_cast<size_t>(std::ceil(len / 8.0)));
        for (size_t i = 0; i < len; i++) {
            out[i / 8] |= ((in[i] & 0x1) << x.shift--);
        }
 
        return static_cast<size_t>(std::ceil(len / 8.0));
    }
};
 
template <>
class utils_helper<int8_t*, uint8_t*, true>
{
public:
    static size_t packed_to_unpacked(int8_t* out, const uint8_t* in, size_t len)
    {
        if (!out || !in || !len) {
            return 0;
        }
 
        for (size_t i = 0; i < len; ++i) {
            *out++ = (((in[i] >> 7) & 0x1) * 255) - 128;
            *out++ = (((in[i] >> 6) & 0x1) * 255) - 128;
            *out++ = (((in[i] >> 5) & 0x1) * 255) - 128;
            *out++ = (((in[i] >> 4) & 0x1) * 255) - 128;
            *out++ = (((in[i] >> 3) & 0x1) * 255) - 128;
            *out++ = (((in[i] >> 2) & 0x1) * 255) - 128;
            *out++ = (((in[i] >> 1) & 0x1) * 255) - 128;
            *out++ = ((in[i] & 0x1) * 255) - 128;
        }
 
        return len * 8;
    }
 
    static size_t unpacked_to_packed(uint8_t* out, const int8_t* in, size_t len)
    {
        if (!out || !in || !len) {
            return 0;
        }
 
        struct h {
            uint8_t shift : 3;
        } x = { .shift = 7 };
 
        memset(out, 0, static_cast<size_t>(std::ceil(len / 8.0)));
        for (size_t i = 0; i < len; i++) {
            uint8_t bit = in[i] > 0 ? 1 : 0;
            out[i / 8] |= (bit << x.shift--);
        }
 
        return static_cast<size_t>(std::ceil(len / 8.0));
    }
};
 
template <>
class utils_helper<itpp::Vec<uint8_t>&, itpp::bvec&, false>
{
public:
    static size_t
    packed_to_unpacked(itpp::Vec<uint8_t>& out, const itpp::bvec& in, size_t len = 0)
    {
        if (!out.size() || !in.size()) {
            return 0;
        }
 
        size_t j = 0;
        for (auto i = 0; i < in.size(); i++) {
            out[j++] = (in[i] >> 7) & 0x1;
            out[j++] = (in[i] >> 6) & 0x1;
            out[j++] = (in[i] >> 5) & 0x1;
            out[j++] = (in[i] >> 4) & 0x1;
            out[j++] = (in[i] >> 3) & 0x1;
            out[j++] = (in[i] >> 2) & 0x1;
            out[j++] = (in[i] >> 1) & 0x1;
            out[j++] = static_cast<bool>(in[i] & itpp::bin(0x1));
        }
 
        return j;
    }
 
    static size_t
    unpacked_to_packed(itpp::bvec& out, const itpp::Vec<uint8_t>& in, size_t len = 0)
    {
        if (!out.size() || !in.size()) {
            return 0;
        }
 
        struct h {
            uint8_t shift : 3;
        } x = { .shift = 7 };
 
        for (size_t i = 0; i < static_cast<size_t>(std::ceil(in.size() / 8.0)); i++) {
            out[i] = 0;
        }
        for (auto i = 0; i < in.size(); i++) {
            ;
            out[i / 8] |= ((in[i] & 0x1) << x.shift--);
        }
 
        return static_cast<size_t>(std::ceil(in.size() / 8.0));
    }
};
 
template <>
class utils_helper<itpp::Vec<int8_t>&, itpp::bvec&, true>
{
public:
    static size_t
    packed_to_unpacked(itpp::Vec<int8_t>& out, const itpp::bvec& in, size_t len = 0)
    {
        if (!out.size() || !in.size()) {
            return 0;
        }
 
        size_t j = 0;
        for (auto i = 0; i < in.size(); ++i) {
            out[j++] = (((in[i] >> 7) & 0x1) * 255) - 128;
            out[j++] = (((in[i] >> 6) & 0x1) * 255) - 128;
            out[j++] = (((in[i] >> 5) & 0x1) * 255) - 128;
            out[j++] = (((in[i] >> 4) & 0x1) * 255) - 128;
            out[j++] = (((in[i] >> 3) & 0x1) * 255) - 128;
            out[j++] = (((in[i] >> 2) & 0x1) * 255) - 128;
            out[j++] = (((in[i] >> 1) & 0x1) * 255) - 128;
            out[j++] = (static_cast<bool>(in[i] & itpp::bin(0x1)) * 255) - 128;
        }
 
        return j;
    }
 
    static size_t
    unpacked_to_packed(itpp::bvec& out, const itpp::Vec<int8_t>& in, size_t len = 0)
    {
        if (!out.size() || !in.size()) {
            return 0;
        }
 
        struct h {
            uint8_t shift : 3;
        } x = { .shift = 7 };
 
        for (auto i = 0; i < static_cast<int>(std::ceil(in.size() / 8.0)); i++) {
            out[i] = 0;
        }
        for (auto i = 0; i < in.size(); i++) {
            uint8_t bit = in[i] > 0 ? 1 : 0;
            out[i / 8] |= (bit << x.shift--);
        }
 
        return static_cast<size_t>(std::ceil(in.size() / 8.0));
    }
};
 
namespace gr {
 
namespace satnogs {
 
/**
 * @brief Several bit-level utility methods, frequently used in the
 * encoding/decoding process
 *
 * @ingroup satnogs
 */
class utils
{
public:
    static double mape(double ref, double estimation);
 
    static uint64_t htonll(uint64_t x);
 
    static uint64_t ntohll(uint64_t x);
 
    static uint32_t bit_count(uint32_t x);
 
    static uint8_t reverse_byte(uint8_t b);
 
    static uint32_t reverse_uint32_bytes(uint32_t i);
 
    static uint64_t reverse_uint64_bytes(uint64_t x);
 
    static void print_pdu(const uint8_t* buf, size_t len);
 
    /**
     * Template function that unpack the bits of the list-like object with numbers in
     * @param out the list with the unpacked bits
     * @param in the list with the packed bits
     * @param len the size of the in
     * @return the size of the out
     */
    template <class T, class U, bool S>
    static size_t packed_to_unpacked(T out, const U in, size_t len = 0)
    {
        return utils_helper<T, U, S>::packed_to_unpacked(out, in, len);
    }
 
    /**
     * Template function that pack the bits of the list-like object with numbers in
     * @param out the list with the packed bits
     * @param in the list with the unpacked bits
     * @param len the size of the in
     * @return the size of the out
     */
    template <class T, class U, bool S>
    static size_t unpacked_to_packed(T out, const U in, size_t len = 0)
    {
        return utils_helper<U, T, S>::unpacked_to_packed(out, in, len);
    }
 
private:
    static constexpr uint8_t s_bytes_reversed[256] = {
        0x00, 0x80, 0x40, 0xC0, 0x20, 0xA0, 0x60, 0xE0, 0x10, 0x90, 0x50, 0xD0, 0x30,
        0xB0, 0x70, 0xF0, 0x08, 0x88, 0x48, 0xC8, 0x28, 0xA8, 0x68, 0xE8, 0x18, 0x98,
        0x58, 0xD8, 0x38, 0xB8, 0x78, 0xF8, 0x04, 0x84, 0x44, 0xC4, 0x24, 0xA4, 0x64,
        0xE4, 0x14, 0x94, 0x54, 0xD4, 0x34, 0xB4, 0x74, 0xF4, 0x0C, 0x8C, 0x4C, 0xCC,
        0x2C, 0xAC, 0x6C, 0xEC, 0x1C, 0x9C, 0x5C, 0xDC, 0x3C, 0xBC, 0x7C, 0xFC, 0x02,
        0x82, 0x42, 0xC2, 0x22, 0xA2, 0x62, 0xE2, 0x12, 0x92, 0x52, 0xD2, 0x32, 0xB2,
        0x72, 0xF2, 0x0A, 0x8A, 0x4A, 0xCA, 0x2A, 0xAA, 0x6A, 0xEA, 0x1A, 0x9A, 0x5A,
        0xDA, 0x3A, 0xBA, 0x7A, 0xFA, 0x06, 0x86, 0x46, 0xC6, 0x26, 0xA6, 0x66, 0xE6,
        0x16, 0x96, 0x56, 0xD6, 0x36, 0xB6, 0x76, 0xF6, 0x0E, 0x8E, 0x4E, 0xCE, 0x2E,
        0xAE, 0x6E, 0xEE, 0x1E, 0x9E, 0x5E, 0xDE, 0x3E, 0xBE, 0x7E, 0xFE, 0x01, 0x81,
        0x41, 0xC1, 0x21, 0xA1, 0x61, 0xE1, 0x11, 0x91, 0x51, 0xD1, 0x31, 0xB1, 0x71,
        0xF1, 0x09, 0x89, 0x49, 0xC9, 0x29, 0xA9, 0x69, 0xE9, 0x19, 0x99, 0x59, 0xD9,
        0x39, 0xB9, 0x79, 0xF9, 0x05, 0x85, 0x45, 0xC5, 0x25, 0xA5, 0x65, 0xE5, 0x15,
        0x95, 0x55, 0xD5, 0x35, 0xB5, 0x75, 0xF5, 0x0D, 0x8D, 0x4D, 0xCD, 0x2D, 0xAD,
        0x6D, 0xED, 0x1D, 0x9D, 0x5D, 0xDD, 0x3D, 0xBD, 0x7D, 0xFD, 0x03, 0x83, 0x43,
        0xC3, 0x23, 0xA3, 0x63, 0xE3, 0x13, 0x93, 0x53, 0xD3, 0x33, 0xB3, 0x73, 0xF3,
        0x0B, 0x8B, 0x4B, 0xCB, 0x2B, 0xAB, 0x6B, 0xEB, 0x1B, 0x9B, 0x5B, 0xDB, 0x3B,
        0xBB, 0x7B, 0xFB, 0x07, 0x87, 0x47, 0xC7, 0x27, 0xA7, 0x67, 0xE7, 0x17, 0x97,
        0x57, 0xD7, 0x37, 0xB7, 0x77, 0xF7, 0x0F, 0x8F, 0x4F, 0xCF, 0x2F, 0xAF, 0x6F,
        0xEF, 0x1F, 0x9F, 0x5F, 0xDF, 0x3F, 0xBF, 0x7F, 0xFF
    };
};
 
} // namespace satnogs
 
} // namespace gr
 
#endif /* INCLUDE_SATNOGS_UTILS_H_ */