Allow shutting down of TcpServers (#1284)

* Delete the server only after all connections are closed and deleted.
* Added command to test remotely server shutdown.
* It should be possible to shut down cleanly all servers that inherit from TcpServer.

Sming/SmingCore/Network/HttpServer.cpp

@@ -26,7 +26,8 @@ HttpServer::HttpServer(HttpServerSettings settings)
 	configure(settings);
 }
 
-void HttpServer::configure(HttpServerSettings settings) {
+void HttpServer::configure(HttpServerSettings settings)
+{
 	this->settings = settings;
 	if(settings.minHeapSize != -1 && settings.minHeapSize > -1) {
 		minHeapSize = settings.minHeapSize;
@@ -61,10 +62,6 @@ TcpConnection* HttpServer::createClient(tcp_pcb *clientTcp)
 	HttpServerConnection* con = new HttpServerConnection(clientTcp);
 	con->setResourceTree(&resourceTree);
 	con->setBodyParsers(&bodyParsers);
-	con->setCompleteDelegate(TcpClientCompleteDelegate(&HttpServer::onConnectionClose, this));
-
-	totalConnections++;
-	debugf("Opening connection. Total connections: %d", totalConnections);
 
 	return con;
 }
@@ -85,21 +82,19 @@ void HttpServer::setDefaultHandler(const HttpPathDelegate& callback)
 	addPath("*", callback);
 }
 
-void HttpServer::addPath(const String& path, const HttpResourceDelegate& onRequestComplete) {
+void HttpServer::addPath(const String& path, const HttpResourceDelegate& onRequestComplete)
+{
 	HttpResource* resource = new HttpResource;
 	resource->onRequestComplete = onRequestComplete;
 	resourceTree[path] = resource;
 }
 
-void HttpServer::addPath(const String& path, HttpResource* resource) {
+void HttpServer::addPath(const String& path, HttpResource* resource)
+{
 	resourceTree[path] = resource;
 }
 
-void HttpServer::setDefaultResource(HttpResource* resource) {
+void HttpServer::setDefaultResource(HttpResource* resource)
+{
 	addPath("*", resource);
 }
-
-void HttpServer::onConnectionClose(TcpClient& connection, bool success) {
-	totalConnections--;
-	debugf("Closing connection. Total connections: %d", totalConnections);
-}

Sming/SmingCore/Network/HttpServer.h

@@ -77,10 +77,8 @@ class HttpServer: public TcpServer
 	void setDefaultHandler(const HttpPathDelegate& callback);
 	void setDefaultResource(HttpResource* resource);
 
-
 protected:
 	virtual TcpConnection* createClient(tcp_pcb *clientTcp);
-	virtual void onConnectionClose(TcpClient& connection, bool success);
 
 protected:
 #ifdef ENABLE_SSL

Sming/SmingCore/Network/TcpConnection.cpp

@@ -38,6 +38,10 @@ TcpConnection::~TcpConnection()
 	freeSslClientKeyCert();
 #endif
 	debugf("~TCP connection");
+
+	if(destroyedDelegate) {
+		destroyedDelegate(*this);
+	}
 }
 
 bool TcpConnection::connect(String server, int port, bool useSsl /* = false */, uint32_t sslOptions /* = 0 */)
@@ -698,12 +702,19 @@ void TcpConnection::staticDnsResponse(const char *name, ip_addr_t *ipaddr, void
 	delete dlook;
 }
 
+void TcpConnection::setDestroyedDelegate(TcpConnectionDestroyedDelegate destroyedDelegate)
+{
+	this->destroyedDelegate = destroyedDelegate;
+}
+
 #ifdef ENABLE_SSL
-void TcpConnection::addSslOptions(uint32_t sslOptions) {
+void TcpConnection::addSslOptions(uint32_t sslOptions)
+{
 	this->sslOptions |= sslOptions;
 }
 
-bool TcpConnection::pinCertificate(const uint8_t *fingerprint, SslFingerprintType type, bool freeAfterHandshake /* = false */) {
+bool TcpConnection::pinCertificate(const uint8_t *fingerprint, SslFingerprintType type, bool freeAfterHandshake /* = false */)
+{
 	int length = 0;
 	uint8_t *localStore;
 
@@ -749,15 +760,17 @@ bool TcpConnection::pinCertificate(const uint8_t *fingerprint, SslFingerprintTyp
 	return true;
 }
 
-bool TcpConnection::pinCertificate(SSLFingerprints fingerprints, bool freeAfterHandshake /* = false */) {
+bool TcpConnection::pinCertificate(SSLFingerprints fingerprints, bool freeAfterHandshake /* = false */)
+{
 	sslFingerprint = fingerprints;
 	freeFingerprints = freeAfterHandshake;
 	return true;
 }
 
 bool TcpConnection::setSslClientKeyCert(const uint8_t *key, int keyLength,
 							 const uint8_t *certificate, int certificateLength,
-							 const char *keyPassword /* = NULL */, bool freeAfterHandshake /* = false */) {
+							 const char *keyPassword /* = NULL */, bool freeAfterHandshake /* = false */)
+{
 
 
 	clientKeyCert.key = new uint8_t[keyLength];
@@ -785,14 +798,16 @@ bool TcpConnection::setSslClientKeyCert(const uint8_t *key, int keyLength,
 	return true;
 }
 
-bool TcpConnection::setSslClientKeyCert(SSLKeyCertPair clientKeyCert, bool freeAfterHandshake /* = false */) {
+bool TcpConnection::setSslClientKeyCert(SSLKeyCertPair clientKeyCert, bool freeAfterHandshake /* = false */)
+{
 	this->clientKeyCert = clientKeyCert;
 	freeClientKeyCert = freeAfterHandshake;
 
 	return true;
 }
 
-void TcpConnection::freeSslClientKeyCert() {
+void TcpConnection::freeSslClientKeyCert()
+{
 	if(clientKeyCert.key) {
 		delete[] clientKeyCert.key;
 		clientKeyCert.key = NULL;
@@ -812,7 +827,8 @@ void TcpConnection::freeSslClientKeyCert() {
 	clientKeyCert.certificateLength = 0;
 }
 
-void TcpConnection::freeSslFingerprints() {
+void TcpConnection::freeSslFingerprints()
+{
 	if(sslFingerprint.certSha1) {
 		delete[] sslFingerprint.certSha1;
 		sslFingerprint.certSha1 = NULL;

Sming/SmingCore/Network/TcpConnection.h

@@ -20,6 +20,7 @@
 
 #include "../Wiring/WiringFrameworkDependencies.h"
 #include "IPAddress.h"
+#include "../Delegate.h"
 
 
 #define NETWORK_DEBUG
@@ -71,6 +72,9 @@ class String;
 class IDataSourceStream;
 class IPAddress;
 class TcpServer;
+class TcpConnection;
+
+typedef Delegate<void(TcpConnection&)> TcpConnectionDestroyedDelegate;
 
 class TcpConnection
 {
@@ -99,6 +103,12 @@ class TcpConnection
 	IPAddress getRemoteIp()  { return (tcp == NULL) ? INADDR_NONE : IPAddress(tcp->remote_ip);};
 	uint16_t getRemotePort() { return (tcp == NULL) ? 0 : tcp->remote_port; };
 
+	/**
+	 * @brief Sets a callback to be called when the object instance is destroyed
+	 * @param TcpServerConnectionDestroyedDelegate destroyedDelegate - callback
+	 */
+	void setDestroyedDelegate(TcpConnectionDestroyedDelegate destroyedDelegate);
+
 #ifdef ENABLE_SSL
 	void addSslOptions(uint32_t sslOptions);
 
@@ -234,6 +244,9 @@ class TcpConnection
 	SSLSessionId* sslSessionId = NULL;
 #endif
 	bool useSsl = false;
+
+private:
+	TcpConnectionDestroyedDelegate destroyedDelegate = 0;
 };
 
 /** @} */

Sming/SmingCore/Network/TcpServer.cpp

@@ -63,6 +63,11 @@ TcpConnection* TcpServer::createClient(tcp_pcb *clientTcp)
 		debugf("TCP Server createClient not NULL");
 	}
 
+	if(!active) {
+		debugf("Refusing new connections. The server is shutting down");
+		return NULL;
+	}
+
 	TcpConnection* con = new TcpClient(clientTcp,
 									   TcpClientDataDelegate(&TcpServer::onClientReceive,this),
 									   TcpClientCompleteDelegate(&TcpServer::onClientComplete,this));
@@ -83,7 +88,8 @@ void TcpServer::setTimeOut(uint16_t waitTimeOut)
 }
 
 #ifdef ENABLE_SSL
-void TcpServer::setServerKeyCert(SSLKeyCertPair serverKeyCert) {
+void TcpServer::setServerKeyCert(SSLKeyCertPair serverKeyCert)
+{
 	clientKeyCert = serverKeyCert;
 }
 #endif
@@ -148,7 +154,7 @@ err_t TcpServer::onAccept(tcp_pcb *clientTcp, err_t err)
 	}
 
 	#ifdef NETWORK_DEBUG
-	debugf("onAccept state: %d K=%d", err, totalConnections);
+	debugf("onAccept state: %d K=%d", err, connections.count());
 	list_mem();
 	#endif
 
@@ -177,6 +183,11 @@ err_t TcpServer::onAccept(tcp_pcb *clientTcp, err_t err)
 	}
 #endif
 
+	client->setDestroyedDelegate(TcpConnectionDestroyedDelegate(&TcpServer::onClientDestroy, this));
+
+	connections.add(client);
+	debugf("Opening connection. Total connections: %d", connections.count());
+
 	onClient((TcpClient*)client);
 
 	return ERR_OK;
@@ -231,3 +242,43 @@ err_t TcpServer::staticAccept(void *arg, tcp_pcb *new_tcp, err_t err)
 	err_t res = con->onAccept(new_tcp, err);
 	return res;
 }
+
+
+void TcpServer::shutdown()
+{
+	active = false;
+
+	debugf("Shutting down the server ...");
+
+	if(tcp) {
+		tcp_arg(tcp, NULL);
+		tcp_accept(tcp, NULL);
+		tcp_close(tcp);
+
+		tcp = NULL;
+	}
+
+	for(int i=0; i < connections.count(); i++) {
+		TcpConnection* connection = connections[i];
+		if(connection == NULL) {
+			continue;
+		}
+
+		connection->setTimeOut(1);
+	}
+}
+
+void TcpServer::onClientDestroy(TcpConnection& connection)
+{
+	connections.removeElement((TcpConnection*)&connection);
+	debugf("Destroying connection. Total connections: %d", connections.count());
+
+	if(active) {
+		return;
+	}
+
+	if(connections.count() == 0) {
+		debugf("Server is destroyed.");
+		delete this;
+	}
+}

Sming/SmingCore/Network/TcpServer.h

@@ -33,6 +33,8 @@ class TcpServer: public TcpConnection {
 	virtual bool listen(int port, bool useSsl = false);
 	void setTimeOut(uint16_t waitTimeOut);
 
+	void shutdown();
+
 #ifdef ENABLE_SSL
 	/**
 	 * @brief Adds SSL support and specifies the server certificate and private key.
@@ -46,8 +48,9 @@ class TcpServer: public TcpConnection {
 
 	virtual err_t onAccept(tcp_pcb *clientTcp, err_t err);
 	virtual void onClient(TcpClient *client);
-	virtual void onClientComplete(TcpClient& client, bool succesfull);
 	virtual bool onClientReceive (TcpClient& client, char *data, int size);
+	virtual void onClientComplete(TcpClient& client, bool succesfull);
+	virtual void onClientDestroy(TcpConnection& connection);
 
 	static err_t staticAccept(void *arg, tcp_pcb *new_tcp, err_t err);
 
@@ -62,6 +65,9 @@ class TcpServer: public TcpConnection {
 	int sslSessionCacheSize = 50;
 #endif
 
+	bool active = true;
+	Vector<TcpConnection*> connections;
+
 private:
 	uint16_t timeOut;
 	TcpClientDataDelegate clientReceiveDelegate = NULL;

samples/HttpServer_WebSockets/app/application.cpp

@@ -52,6 +52,14 @@ void wsConnected(WebSocketConnection& socket)
 void wsMessageReceived(WebSocketConnection& socket, const String& message)
 {
 	Serial.printf("WebSocket message received:\r\n%s\r\n", message.c_str());
+
+	if(message == "shutdown") {
+		String message = "The server is shutting down...";
+		socket.broadcast(message.c_str(), message.length());
+		server.shutdown();
+		return;
+	}
+
 	String response = "Echo: " + message;
 	socket.sendString(response);