Improve code with std::unique_ptr (#2643)

* **Memory management improvements**
Switch to using `unique_ptr` instead of raw pointers to prevent memory leaks and ease resource management.
* **Fix memory leaks in StreamTransformer.cpp**
Address memory leaks, enhancing application stability and performance.
* **Simplify and improve CommandOutput.cpp**
Replace a code segment with a more efficient and straightforward approach.
* **Refactor Basic_Audio sample application**
Incorporate smart pointers and reorganize some code segments for better code quality and memory safety.

Sming/Components/Hosted/include/Hosted/Transport/TcpClientTransport.h

@@ -16,6 +16,7 @@
 #include <Network/TcpClient.h>
 #include "TcpTransport.h"
 #include "TcpClientStream.h"
+#include <memory>
 
 namespace Hosted
 {
@@ -27,12 +28,7 @@ class TcpClientTransport : public TcpTransport
 	TcpClientTransport(TcpClient& client)
 	{
 		client.setReceiveDelegate(TcpClientDataDelegate(&TcpClientTransport::process, this));
-		stream = new TcpClientStream(client);
-	}
-
-	~TcpClientTransport()
-	{
-		delete stream;
+		stream.reset(new TcpClientStream(client));
 	}
 
 protected:
@@ -46,7 +42,7 @@ class TcpClientTransport : public TcpTransport
 	}
 
 private:
-	TcpClientStream* stream = nullptr;
+	std::unique_ptr<TcpClientStream> stream;
 };
 
 } // namespace Transport

Sming/Components/Network/Arch/Esp8266/Platform/AccessPointImpl.cpp

@@ -82,11 +82,7 @@ bool AccessPointImpl::config(const String& ssid, String password, AUTH_MODE mode
 			debugf("AP configuration was updated");
 		} else {
 			debugf("Set AP configuration in background");
-			if(runConfig != nullptr) {
-				delete runConfig;
-			}
-			runConfig = new softap_config();
-			memcpy(runConfig, &config, sizeof(softap_config));
+			runConfig.reset(new softap_config(config));
 		}
 	} else {
 		debugf("AP configuration loaded");
@@ -190,22 +186,23 @@ std::unique_ptr<StationList> AccessPointImpl::getStations() const
 
 void AccessPointImpl::onSystemReady()
 {
-	if(runConfig != nullptr) {
-		noInterrupts();
-		bool enabled = isEnabled();
-		enable(true, false);
-		wifi_softap_dhcps_stop();
-
-		if(!wifi_softap_set_config(runConfig)) {
-			debugf("Can't set AP config on system ready event!");
-		} else {
-			debugf("AP configuration was updated on system ready event");
-		}
-		delete runConfig;
-		runConfig = nullptr;
+	if(!runConfig) {
+		return;
+	}
+
+	noInterrupts();
+	bool enabled = isEnabled();
+	enable(true, false);
+	wifi_softap_dhcps_stop();
 
-		wifi_softap_dhcps_start();
-		enable(enabled, false);
-		interrupts();
+	if(!wifi_softap_set_config(runConfig.get())) {
+		debugf("Can't set AP config on system ready event!");
+	} else {
+		debugf("AP configuration was updated on system ready event");
 	}
+	runConfig.reset();
+
+	wifi_softap_dhcps_start();
+	enable(enabled, false);
+	interrupts();
 }

Sming/Components/Network/Arch/Esp8266/Platform/AccessPointImpl.h

@@ -40,5 +40,5 @@ class AccessPointImpl : public AccessPointClass, protected ISystemReadyHandler
 	void onSystemReady() override;
 
 private:
-	softap_config* runConfig = nullptr;
+	std::unique_ptr<softap_config> runConfig;
 };

Sming/Components/rboot/include/Network/RbootHttpUpdater.h

@@ -33,25 +33,21 @@ class RbootHttpUpdater : protected HttpClient
 	struct Item {
 		String url;
 		uint32_t targetOffset;
-		size_t size;						// << max allowed size
-		RbootOutputStream* stream{nullptr}; // (optional) output stream to use.
+		size_t size;							   // << max allowed size
+		std::unique_ptr<RbootOutputStream> stream; // (optional) output stream to use.
 
 		Item(String url, uint32_t targetOffset, size_t size, RbootOutputStream* stream)
-			: url(url), targetOffset(targetOffset), size(size), stream(stream)
+			: url(url), targetOffset(targetOffset), size(size)
 		{
-		}
-
-		~Item()
-		{
-			delete stream;
+			this->stream.reset(stream);
 		}
 
 		RbootOutputStream* getStream()
 		{
-			if(stream == nullptr) {
-				stream = new RbootOutputStream(targetOffset, size);
+			if(!stream) {
+				stream.reset(new RbootOutputStream(targetOffset, size));
 			}
-			return stream;
+			return stream.get();
 		}
 	};
 

Sming/Components/ssl/Axtls/AxConnection.h

@@ -16,6 +16,7 @@
 #include <Network/Ssl/Validator.h>
 #include "AxCertificate.h"
 #include "AxError.h"
+#include <memory>
 
 namespace Ssl
 {
@@ -26,7 +27,6 @@ class AxConnection : public Connection
 
 	~AxConnection()
 	{
-		delete certificate;
 		// Typically sends out closing message
 		ssl_free(ssl);
 	}
@@ -60,17 +60,16 @@ class AxConnection : public Connection
 
 	const Certificate* getCertificate() const override
 	{
-		if(certificate == nullptr && ssl->x509_ctx != nullptr) {
-			certificate = new AxCertificate(ssl);
+		if(!certificate && ssl->x509_ctx != nullptr) {
+			certificate.reset(new AxCertificate(ssl));
 		}
 
-		return certificate;
+		return certificate.get();
 	}
 
 	void freeCertificate() override
 	{
-		delete certificate;
-		certificate = nullptr;
+		certificate.reset();
 	}
 
 	int read(InputBuffer& input, uint8_t*& output) override;
@@ -93,7 +92,7 @@ class AxConnection : public Connection
 
 private:
 	SSL* ssl{nullptr};
-	mutable AxCertificate* certificate{nullptr};
+	mutable std::unique_ptr<AxCertificate> certificate;
 	InputBuffer* input{nullptr};
 };
 

Sming/Components/ssl/include/Network/Ssl/Session.h

@@ -14,6 +14,7 @@
 #include "KeyCertPair.h"
 #include "ValidatorList.h"
 #include <Platform/System.h>
+#include <memory>
 
 class TcpConnection;
 
@@ -121,7 +122,6 @@ class Session
 	~Session()
 	{
 		close();
-		delete sessionId;
 	}
 
 	/**
@@ -130,7 +130,7 @@ class Session
 	 */
 	const SessionId* getSessionId() const
 	{
-		return sessionId;
+		return sessionId.get();
 	}
 
 	/**
@@ -147,8 +147,8 @@ class Session
 	 */
 	void setConnection(Connection* connection)
 	{
-		assert(this->connection == nullptr);
-		this->connection = connection;
+		assert(!this->connection);
+		this->connection.reset(connection);
 	}
 
 	/**
@@ -157,7 +157,7 @@ class Session
 	 */
 	Connection* getConnection()
 	{
-		return connection;
+		return connection.get();
 	}
 
 	/**
@@ -223,9 +223,9 @@ class Session
 	void endHandshake();
 
 private:
-	Context* context = nullptr;
-	Connection* connection = nullptr;
-	SessionId* sessionId = nullptr;
+	std::unique_ptr<Context> context;
+	std::unique_ptr<Connection> connection;
+	std::unique_ptr<SessionId> sessionId;
 	CpuFrequency curFreq = CpuFrequency(0);
 };
 

Sming/Components/ssl/src/Session.cpp

@@ -48,10 +48,10 @@ bool Session::onAccept(TcpConnection* client, tcp_pcb* tcp)
 		return false;
 	}
 
-	if(context == nullptr) {
+	if(!context) {
 		assert(factory != nullptr);
-		context = factory->createContext(*this);
-		if(context == nullptr) {
+		context.reset(factory->createContext(*this));
+		if(!context) {
 			return false;
 		}
 
@@ -73,14 +73,14 @@ bool Session::onConnect(tcp_pcb* tcp)
 {
 	debug_d("SSL %p: Starting connection...", this);
 
-	assert(connection == nullptr);
-	assert(context == nullptr);
+	assert(!connection);
+	assert(!context);
 
 	// Client Session
-	delete context;
+	context.reset();
 	assert(factory != nullptr);
-	context = factory->createContext(*this);
-	if(context == nullptr) {
+	context.reset(factory->createContext(*this));
+	if(!context) {
 		return false;
 	}
 
@@ -90,16 +90,16 @@ bool Session::onConnect(tcp_pcb* tcp)
 		return false;
 	}
 
-	if(sessionId != nullptr && sessionId->isValid()) {
+	if(sessionId && sessionId->isValid()) {
 		debug_d("-----BEGIN SSL SESSION PARAMETERS-----");
 		debug_d("SessionId: %s", toString(*sessionId).c_str());
 		debug_d("------END SSL SESSION PARAMETERS------");
 	}
 
 	beginHandshake();
 
-	connection = context->createClient(tcp);
-	if(connection == nullptr) {
+	connection.reset(context->createClient(tcp));
+	if(!connection) {
 		endHandshake();
 		return false;
 	}
@@ -134,19 +134,16 @@ void Session::close()
 {
 	debug_d("SSL %p: closing ...", this);
 
-	delete connection;
-	connection = nullptr;
-
-	delete context;
-	context = nullptr;
+	connection.reset();
+	context.reset();
 
 	hostName = nullptr;
 	maxBufferSize = MaxBufferSize::Default;
 }
 
 int Session::read(InputBuffer& input, uint8_t*& output)
 {
-	if(connection == nullptr) {
+	if(!connection) {
 		debug_w("SSL: no connection");
 		return -1;
 	}
@@ -165,7 +162,7 @@ int Session::read(InputBuffer& input, uint8_t*& output)
 
 int Session::write(const uint8_t* data, size_t length)
 {
-	if(connection == nullptr) {
+	if(!connection) {
 		debug_e("!! SSL Session connection is NULL");
 		return ERR_CONN;
 	}
@@ -181,7 +178,7 @@ int Session::write(const uint8_t* data, size_t length)
 
 bool Session::validateCertificate()
 {
-	if(connection == nullptr) {
+	if(!connection) {
 		debug_w("SSL: connection not set, assuming cert. is OK");
 		return true;
 	}
@@ -202,16 +199,16 @@ void Session::handshakeComplete(bool success)
 	if(success) {
 		// If requested, take a copy of the session ID for later re-use
 		if(options.sessionResume) {
-			if(sessionId == nullptr) {
-				sessionId = new SessionId;
+			if(!sessionId) {
+				sessionId.reset(new SessionId);
 			}
 			*sessionId = connection->getSessionId();
 		}
 	} else {
 		debug_w("SSL Handshake failed");
 	}
 
-	if(options.freeKeyCertAfterHandshake && connection != nullptr) {
+	if(options.freeKeyCertAfterHandshake && connection) {
 		connection->freeCertificate();
 	}
 }
@@ -235,7 +232,7 @@ size_t Session::printTo(Print& p) const
 	n += p.println(keyCert.getCertificateLength());
 	n += p.print(_F("  Cert PK Length: "));
 	n += p.println(keyCert.getKeyLength());
-	if(connection != nullptr) {
+	if(connection) {
 		n += connection->printTo(p);
 	}