MMDVMHost-Private/FMNetwork.cpp
2020-05-16 17:45:24 +02:00

188 lines
4 KiB
C++

/*
* Copyright (C) 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 "FMNetwork.h"
#include "Defines.h"
#include "Utils.h"
#include "Log.h"
#include <cstdio>
#include <cassert>
#include <cstring>
const unsigned int BUFFER_LENGTH = 500U;
CFMNetwork::CFMNetwork(const std::string& localAddress, unsigned int localPort, const std::string& gatewayAddress, unsigned int gatewayPort, bool debug) :
m_socket(localAddress, localPort),
m_address(),
m_port(gatewayPort),
m_debug(debug),
m_enabled(false),
m_buffer(2000U, "FM Network"),
m_pollTimer(1000U, 5U)
{
assert(gatewayPort > 0U);
assert(!gatewayAddress.empty());
m_address = CUDPSocket::lookup(gatewayAddress);
}
CFMNetwork::~CFMNetwork()
{
}
bool CFMNetwork::open()
{
LogMessage("Opening FM network connection");
if (m_address.s_addr == INADDR_NONE)
return false;
m_pollTimer.start();
return m_socket.open();
}
bool CFMNetwork::writeData(const unsigned char* data, unsigned int length)
{
assert(data != NULL);
unsigned char buffer[500U];
::memset(buffer, 0x00U, 500U);
buffer[0U] = 'F';
buffer[1U] = 'M';
buffer[2U] = 'D';
::memcpy(buffer + 3U, data, length);
if (m_debug)
CUtils::dump(1U, "FM Network Data Sent", buffer, length + 3U);
return m_socket.write(buffer, length + 3U, m_address, m_port);
}
bool CFMNetwork::writeEOT()
{
unsigned char buffer[10U];
::memset(buffer, 0x00U, 10U);
buffer[0U] = 'F';
buffer[1U] = 'M';
buffer[2U] = 'E';
if (m_debug)
CUtils::dump(1U, "FM Network End of Transmission Sent", buffer, 3U);
return m_socket.write(buffer, 3U, m_address, m_port);
}
void CFMNetwork::clock(unsigned int ms)
{
m_pollTimer.clock(ms);
if (m_pollTimer.hasExpired()) {
writePoll();
m_pollTimer.start();
}
unsigned char buffer[BUFFER_LENGTH];
in_addr address;
unsigned int port;
int length = m_socket.read(buffer, BUFFER_LENGTH, address, port);
if (length <= 0)
return;
// Check if the data is for us
if (m_address.s_addr != address.s_addr || port != m_port) {
LogMessage("FM packet received from an invalid source, %08X != %08X and/or %u != %u", m_address.s_addr, address.s_addr, m_port, port);
return;
}
// Ignore incoming polls
if (::memcmp(buffer, "FMP", 3U) == 0)
return;
// Invalid packet type?
if (::memcmp(buffer, "FMD", 3U) != 0)
return;
if (!m_enabled)
return;
if (m_debug)
CUtils::dump(1U, "FM Network Data Received", buffer, length);
m_buffer.addData(buffer + 3U, length - 3U);
}
unsigned int CFMNetwork::read(unsigned char* data, unsigned int space)
{
assert(data != NULL);
unsigned int bytes = m_buffer.dataSize();
if (bytes == 0U)
return 0U;
if (bytes < space)
space = bytes;
//we store usignedshorts, therefore ensure we always return and even number of data
if(space > 0 && space % 2 != 0)
space--;//round down to multiple of 2
m_buffer.getData(data, space);
return space;
}
void CFMNetwork::reset()
{
}
void CFMNetwork::close()
{
m_socket.close();
LogMessage("Closing FM network connection");
}
void CFMNetwork::enable(bool enabled)
{
if (enabled && !m_enabled)
reset();
else if (!enabled && m_enabled)
m_buffer.clear();
m_enabled = enabled;
}
bool CFMNetwork::writePoll()
{
unsigned char buffer[3U];
buffer[0U] = 'F';
buffer[1U] = 'M';
buffer[2U] = 'P';
if (m_debug)
CUtils::dump(1U, "FM Network Poll Sent", buffer, 3U);
return m_socket.write(buffer, 3U, m_address, m_port);
}