MMDVMHost-Private/M17Network.cpp
2020-10-14 16:16:54 +01:00

133 lines
2.8 KiB
C++

/*
* Copyright (C) 2009-2014,2016,2019,2020 by Jonathan Naylor G4KLX
*
* 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 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, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#include "M17Network.h"
#include "M17Defines.h"
#include "Defines.h"
#include "Utils.h"
#include "Log.h"
#include <cstdio>
#include <cassert>
#include <cstring>
const unsigned int BUFFER_LENGTH = 200U;
CM17Network::CM17Network(unsigned int localPort, const std::string& gatewayAddress, unsigned int gatewayPort, bool debug) :
m_socket(localPort),
m_addr(),
m_addrLen(0U),
m_debug(debug),
m_enabled(false),
m_buffer(1000U, "M17 Network")
{
if (CUDPSocket::lookup(gatewayAddress, gatewayPort, m_addr, m_addrLen) != 0)
m_addrLen = 0U;
}
CM17Network::~CM17Network()
{
}
bool CM17Network::open()
{
if (m_addrLen == 0U) {
LogError("Unable to resolve the address of the M17 Gateway");
return false;
}
LogMessage("Opening M17 network connection");
return m_socket.open(m_addr);
}
bool CM17Network::write(const unsigned char* data)
{
assert(data != NULL);
unsigned char buffer[100U];
buffer[0U] = 'M';
buffer[1U] = '1';
buffer[2U] = '7';
if (m_debug)
CUtils::dump(1U, "M17 data transmitted", buffer, 36U);
return m_socket.write(buffer, 36U, m_addr, m_addrLen);
}
void CM17Network::clock(unsigned int ms)
{
unsigned char buffer[BUFFER_LENGTH];
sockaddr_storage address;
unsigned int addrLen;
int length = m_socket.read(buffer, BUFFER_LENGTH, address, addrLen);
if (length <= 0)
return;
if (!CUDPSocket::match(m_addr, address)) {
LogMessage("M17, packet received from an invalid source");
return;
}
if (!m_enabled)
return;
if (m_debug)
CUtils::dump(1U, "M17 Network Data Received", buffer, length);
if (::memcmp(buffer + 0U, "M17", 3U) != 0)
return;
unsigned char c = length;
m_buffer.addData(&c, 1U);
m_buffer.addData(buffer, length);
}
bool CM17Network::read(unsigned char* data)
{
assert(data != NULL);
if (m_buffer.isEmpty())
return false;
unsigned char c = 0U;
m_buffer.getData(&c, 1U);
m_buffer.getData(data, c);
return true;
}
void CM17Network::close()
{
m_socket.close();
LogMessage("Closing M17 network connection");
}
void CM17Network::enable(bool enabled)
{
if (!enabled && m_enabled)
m_buffer.clear();
m_enabled = enabled;
}