Add M17 reflector linking and start on the frame handling.

M17Network.cpp

@@ -18,6 +18,7 @@
 
 #include "M17Network.h"
 #include "M17Defines.h"
+#include "M17Utils.h"
 #include "Defines.h"
 #include "Utils.h"
 #include "Log.h"
@@ -28,8 +29,8 @@
 
 const unsigned int BUFFER_LENGTH = 200U;
 
-CM17Network::CM17Network(unsigned int localPort, const std::string& gatewayAddress, unsigned int gatewayPort, bool debug) :
-m_socket(localPort),
+CM17Network::CM17Network(unsigned int port, bool debug) :
+m_socket(port),
 m_addr(),
 m_addrLen(0U),
 m_debug(debug),
@@ -37,34 +38,69 @@ m_enabled(false),
 m_outId(0U),
 m_inId(0U),
 m_buffer(1000U, "M17 Network"),
-m_random()
+m_random(),
+m_state(M17N_NOTLINKED),
+m_reflector(NULL),
+m_module(' '),
+m_timer(1000U, 5U)
 {
 	std::random_device rd;
 	std::mt19937 mt(rd());
 	m_random = mt;
 
-	if (CUDPSocket::lookup(gatewayAddress, gatewayPort, m_addr, m_addrLen) != 0)
-		m_addrLen = 0U;
+	m_encoded = new unsigned char[6U];
 }
 
 CM17Network::~CM17Network()
 {
+	delete[] m_encoded;
 }
 
 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::link(const std::string& address, unsigned int port, const std::string& reflector, char module)
+{
+	if (CUDPSocket::lookup(address, port, m_addr, m_addrLen) != 0) {
+		m_state = M17N_NOTLINKED;
+		return false;
+	}
+
+	m_reflector = reflector;
+	m_module    = module;
+
+	CM17Utils::encodeCallsign(m_reflector, m_encoded);
+
+	m_state = M17N_LINKING;
+
+	sendConnect();
+
+	m_timer.start();
+
+	return true;
+}
+
+void CM17Network::unlink()
+{
+	if (m_state != M17N_LINKED)
+		return;
+
+	m_state = M17N_UNLINKING;
+
+	sendConnect();
+
+	m_timer.start();
+}
+
 bool CM17Network::write(const unsigned char* data)
 {
+	if (m_state != M17N_LINKED)
+		return false;
+
 	assert(data != NULL);
 
 	unsigned char buffer[100U];
@@ -91,6 +127,23 @@ bool CM17Network::write(const unsigned char* data)
 
 void CM17Network::clock(unsigned int ms)
 {
+	m_timer.clock(ms);
+	if (m_timer.isRunning() && m_timer.hasExpired()) {
+		switch (m_state) {
+		case M17N_LINKING:
+			sendConnect();
+			m_timer.start();
+			break;
+		case M17N_UNLINKING:
+			sendDisconnect();
+			m_timer.start();
+			break;
+		default:
+			m_timer.stop();
+			break;
+		}
+	}
+
 	unsigned char buffer[BUFFER_LENGTH];
 
 	sockaddr_storage address;
@@ -104,14 +157,42 @@ void CM17Network::clock(unsigned int ms)
 		return;
 	}
 
-	if (!m_enabled)
-		return;
-
 	if (m_debug)
 		CUtils::dump(1U, "M17 Network Data Received", buffer, length);
 
-	if (::memcmp(buffer + 0U, "M17 ", 4U) != 0)
+	if (::memcmp(buffer + 0U, "ACKN", 4U) == 0) {
+		m_timer.stop();
+		m_state = M17N_LINKED;
+		LogMessage("M17, linked to %s", m_reflector.c_str());
 		return;
+	}
+
+	if (::memcmp(buffer + 0U, "NACK", 4U) == 0) {
+		m_timer.stop();
+		m_state = M17N_NOTLINKED;
+		LogMessage("M17, link refused by %s", m_reflector.c_str());
+		return;
+	}
+
+	if (::memcmp(buffer + 0U, "PING", 4U) == 0) {
+		sendPong();
+		return;
+	}
+
+	if (::memcmp(buffer + 0U, "DISC", 4U) == 0) {
+		m_timer.stop();
+		m_state = M17N_NOTLINKED;
+		LogMessage("M17, unlinked from %s", m_reflector.c_str());
+		return;
+	}
+
+	if (!m_enabled)
+		return;
+
+	if (::memcmp(buffer + 0U, "M17 ", 4U) != 0) {
+		CUtils::dump(2U, "M17, received unknown packet", buffer, length);
+		return;
+	}
 
 	uint16_t id = (buffer[4U] << 8) + (buffer[5U] << 0);
 	if (m_inId == 0U) {
@@ -167,3 +248,71 @@ void CM17Network::enable(bool enabled)
 
 	m_enabled = enabled;
 }
+
+void CM17Network::sendConnect()
+{
+	unsigned char buffer[15U];
+
+	buffer[0U] = 'C';
+	buffer[1U] = 'O';
+	buffer[2U] = 'N';
+	buffer[3U] = 'N';
+
+	buffer[4U] = m_encoded[0U];
+	buffer[5U] = m_encoded[1U];
+	buffer[6U] = m_encoded[2U];
+	buffer[7U] = m_encoded[3U];
+	buffer[8U] = m_encoded[4U];
+	buffer[9U] = m_encoded[5U];
+
+	buffer[10U] = m_module;
+
+	if (m_debug)
+		CUtils::dump(1U, "M17 data transmitted", buffer, 11U);
+
+	m_socket.write(buffer, 11U, m_addr, m_addrLen);
+}
+
+void CM17Network::sendPong()
+{
+	unsigned char buffer[15U];
+
+	buffer[0U] = 'P';
+	buffer[1U] = 'O';
+	buffer[2U] = 'N';
+	buffer[3U] = 'G';
+
+	buffer[4U] = m_encoded[0U];
+	buffer[5U] = m_encoded[1U];
+	buffer[6U] = m_encoded[2U];
+	buffer[7U] = m_encoded[3U];
+	buffer[8U] = m_encoded[4U];
+	buffer[9U] = m_encoded[5U];
+
+	if (m_debug)
+		CUtils::dump(1U, "M17 data transmitted", buffer, 10U);
+
+	m_socket.write(buffer, 10U, m_addr, m_addrLen);
+}
+
+void CM17Network::sendDisconnect()
+{
+	unsigned char buffer[15U];
+
+	buffer[0U] = 'D';
+	buffer[1U] = 'I';
+	buffer[2U] = 'S';
+	buffer[3U] = 'C';
+
+	buffer[4U] = m_encoded[0U];
+	buffer[5U] = m_encoded[1U];
+	buffer[6U] = m_encoded[2U];
+	buffer[7U] = m_encoded[3U];
+	buffer[8U] = m_encoded[4U];
+	buffer[9U] = m_encoded[5U];
+
+	if (m_debug)
+		CUtils::dump(1U, "M17 data transmitted", buffer, 10U);
+
+	m_socket.write(buffer, 10U, m_addr, m_addrLen);
+}