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mayhem-firmware/firmware/application/protocols/aprs.cpp
T

98 lines
3.0 KiB
C++

/*
* Copyright (C) 2014 Jared Boone, ShareBrained Technology, Inc.
* Copyright (C) 2017 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 <cstdint>
#include "aprs.hpp"
#include "ax25.hpp"
#include "portapack_persistent_memory.hpp"
using namespace ax25;
namespace aprs {
void make_aprs_frame(const char* src_address, const uint32_t src_ssid, const char* dest_address, const uint32_t dest_ssid, const std::string& payload, const std::string& path) {
AX25Frame frame;
char address[14] = {0};
memset(address, ' ', 14);
size_t dest_len = strlen(dest_address);
if (dest_len > 6) dest_len = 6;
memcpy(&address[0], dest_address, dest_len);
size_t src_len = strlen(src_address);
if (src_len > 6) src_len = 6;
memcpy(&address[7], src_address, src_len);
// euquiq: According to ax.25 doc section 2.2.13.x.x and 2.4.1.2
// SSID need bits 5.6 set, so later when shifted it will end up being 011xxxx0 (xxxx = SSID number)
// Notice that if need to signal usage of AX.25 V2.0, (dest_ssid | 112); (MSb will need to be set at the end)
address[6] = (dest_ssid | 0x30);
address[13] = (src_ssid | 0x30);
// fix path ssid bits. the result will be the same as above
std::string fixed_path = "";
const char* p = path.c_str();
while (*p) {
while (*p == ' ') p++;
if (!*p) break;
char call[6] = {' ', ' ', ' ', ' ', ' ', ' '};
int idx = 0;
while (*p && *p != '-' && *p != ',') {
if (*p != ' ') {
if (idx < 6) {
char c = *p;
if (c >= 'a' && c <= 'z') c -= 32;
call[idx++] = c;
}
}
p++;
}
int ssid = 0;
if (*p == '-') {
p++;
while (*p == ' ') p++;
while (*p >= '0' && *p <= '9') {
ssid = ssid * 10 + (*p - '0');
p++;
}
}
if (ssid >= 0 && ssid <= 15) {
for (int i = 0; i < 6; i++) fixed_path += call[i];
fixed_path += (char)(ssid | 0x30);
}
while (*p && *p != ',') p++;
if (*p == ',') p++;
}
frame.make_ui_frame(address, 0x03, protocol_id_t::NO_LAYER3, payload, fixed_path);
}
} /* namespace aprs */