support for multiple http servers (#473)

* added support for having multiple http servers active in one session
* added configuration API to pluggable transports
* removed pimpl pattern from some pluggable transports implementations

6 files changed, 166 insertions, 177 deletions

diff --git a/src/zenhttp/transports/asiotransport.cpp b/src/zenhttp/transports/asiotransport.cpp
index b8fef8f5f..ab053a748 100644
--- a/src/zenhttp/transports/asiotransport.cpp
+++ b/src/zenhttp/transports/asiotransport.cpp
@@ -31,18 +31,19 @@ struct AsioTransportAcceptor;
 class AsioTransportPlugin : public TransportPlugin, RefCounted
 {
 public:
-	AsioTransportPlugin(uint16_t BasePort, unsigned int ThreadCount);
+	AsioTransportPlugin();
 	~AsioTransportPlugin();
 
 	virtual uint32_t AddRef() const override;
 	virtual uint32_t Release() const override;
+	virtual void	 Configure(const char* OptionTag, const char* OptionValue) override;
 	virtual void	 Initialize(TransportServer* ServerInterface) override;
 	virtual void	 Shutdown() override;
 	virtual bool	 IsAvailable() override;
 
 private:
 	bool	 m_IsOk		   = true;
-	uint16_t m_BasePort	   = 0;
+	uint16_t m_BasePort	   = 8558;
 	int		 m_ThreadCount = 0;
 
 	asio::io_service					   m_IoService;
@@ -349,9 +350,7 @@ AsioTransportConnection::OnResponseDataSent(const asio::error_code& Ec, std::siz
 
 //////////////////////////////////////////////////////////////////////////
 
-AsioTransportPlugin::AsioTransportPlugin(uint16_t BasePort, unsigned int ThreadCount)
-: m_BasePort(BasePort)
-, m_ThreadCount(ThreadCount != 0 ? ThreadCount : Max(std::thread::hardware_concurrency(), 8u))
+AsioTransportPlugin::AsioTransportPlugin() : m_ThreadCount(Max(std::thread::hardware_concurrency(), 8u))
 {
 }
 
@@ -372,6 +371,31 @@ AsioTransportPlugin::Release() const
 }
 
 void
+AsioTransportPlugin::Configure(const char* OptionTag, const char* OptionValue)
+{
+	using namespace std::literals;
+
+	if (OptionTag == "port"sv)
+	{
+		if (auto PortNum = ParseInt<uint16_t>(OptionValue))
+		{
+			m_BasePort = *PortNum;
+		}
+	}
+	else if (OptionTag == "threads"sv)
+	{
+		if (auto ThreadCount = ParseInt<int>(OptionValue))
+		{
+			m_ThreadCount = *ThreadCount;
+		}
+	}
+	else
+	{
+		// Unknown configuration option
+	}
+}
+
+void
 AsioTransportPlugin::Initialize(TransportServer* ServerInterface)
 {
 	ZEN_ASSERT(m_ThreadCount > 0);
@@ -429,9 +453,9 @@ AsioTransportPlugin::IsAvailable()
 }
 
 TransportPlugin*
-CreateAsioTransportPlugin(uint16_t BasePort, unsigned int ThreadCount)
+CreateAsioTransportPlugin()
 {
-	return new AsioTransportPlugin(BasePort, ThreadCount);
+	return new AsioTransportPlugin();
 }
 
 }  // namespace zen
diff --git a/src/zenhttp/transports/asiotransport.h b/src/zenhttp/transports/asiotransport.h
index b10174b85..25f122b5b 100644
--- a/src/zenhttp/transports/asiotransport.h
+++ b/src/zenhttp/transports/asiotransport.h
@@ -8,7 +8,7 @@
 
 namespace zen {
 
-TransportPlugin* CreateAsioTransportPlugin(uint16_t BasePort, unsigned int ThreadCount);
+TransportPlugin* CreateAsioTransportPlugin();
 
 }  // namespace zen
 
diff --git a/src/zenhttp/transports/dlltransport.cpp b/src/zenhttp/transports/dlltransport.cpp
index 04fb6caaa..5c0084e44 100644
--- a/src/zenhttp/transports/dlltransport.cpp
+++ b/src/zenhttp/transports/dlltransport.cpp
@@ -86,28 +86,29 @@ struct LoadedDll
 	Ref<TransportPlugin>  Plugin;
 };
 
-class DllTransportPluginImpl
+class DllTransportPluginImpl : public DllTransportPlugin, RefCounted
 {
 public:
-	DllTransportPluginImpl(uint16_t BasePort, unsigned int ThreadCount);
+	DllTransportPluginImpl();
 	~DllTransportPluginImpl();
 
-	uint16_t Start(TransportServer* ServerInterface);
-	void	 Stop();
-	bool	 IsAvailable();
-	void	 LoadDll(std::string_view Name);
+	virtual uint32_t AddRef() const override;
+	virtual uint32_t Release() const override;
+	virtual void	 Configure(const char* OptionTag, const char* OptionValue) override;
+	virtual void	 Initialize(TransportServer* ServerInterface) override;
+	virtual void	 Shutdown() override;
+	virtual bool	 IsAvailable() override;
+
+	virtual void LoadDll(std::string_view Name) override;
+	virtual void ConfigureDll(std::string_view Name, const char* OptionTag, const char* OptionValue) override;
 
 private:
 	TransportServer*	   m_ServerInterface = nullptr;
 	RwLock				   m_Lock;
 	std::vector<LoadedDll> m_Transports;
-	uint16_t			   m_BasePort	 = 0;
-	int					   m_ThreadCount = 0;
 };
 
-DllTransportPluginImpl::DllTransportPluginImpl(uint16_t BasePort, unsigned int ThreadCount)
-: m_BasePort(BasePort)
-, m_ThreadCount(ThreadCount != 0 ? ThreadCount : Max(std::thread::hardware_concurrency(), 8u))
+DllTransportPluginImpl::DllTransportPluginImpl()
 {
 }
 
@@ -115,8 +116,28 @@ DllTransportPluginImpl::~DllTransportPluginImpl()
 {
 }
 
-uint16_t
-DllTransportPluginImpl::Start(TransportServer* ServerIface)
+uint32_t
+DllTransportPluginImpl::AddRef() const
+{
+	return RefCounted::AddRef();
+}
+
+uint32_t
+DllTransportPluginImpl::Release() const
+{
+	return RefCounted::Release();
+}
+
+void
+DllTransportPluginImpl::Configure(const char* OptionTag, const char* OptionValue)
+{
+	// No configuration options
+
+	ZEN_UNUSED(OptionTag, OptionValue);
+}
+
+void
+DllTransportPluginImpl::Initialize(TransportServer* ServerIface)
 {
 	m_ServerInterface = ServerIface;
 
@@ -133,12 +154,10 @@ DllTransportPluginImpl::Start(TransportServer* ServerIface)
 			// TODO: report
 		}
 	}
-
-	return m_BasePort;
 }
 
 void
-DllTransportPluginImpl::Stop()
+DllTransportPluginImpl::Shutdown()
 {
 	RwLock::ExclusiveLockScope _(m_Lock);
 
@@ -162,8 +181,24 @@ DllTransportPluginImpl::IsAvailable()
 }
 
 void
+DllTransportPluginImpl::ConfigureDll(std::string_view Name, const char* OptionTag, const char* OptionValue)
+{
+	RwLock::ExclusiveLockScope _(m_Lock);
+
+	for (auto& Transport : m_Transports)
+	{
+		if (Transport.Name == Name)
+		{
+			Transport.Plugin->Configure(OptionTag, OptionValue);
+		}
+	}
+}
+
+void
 DllTransportPluginImpl::LoadDll(std::string_view Name)
 {
+	RwLock::ExclusiveLockScope _(m_Lock);
+
 	ExtendableStringBuilder<128> DllPath;
 	DllPath << Name << ".dll";
 	HMODULE DllHandle = LoadLibraryA(DllPath.c_str());
@@ -197,52 +232,10 @@ DllTransportPluginImpl::LoadDll(std::string_view Name)
 	m_Transports.emplace_back(std::move(NewDll));
 }
 
-//////////////////////////////////////////////////////////////////////////
-
-DllTransportPlugin::DllTransportPlugin(uint16_t BasePort, unsigned int ThreadCount)
-: m_Impl(std::make_unique<DllTransportPluginImpl>(BasePort, ThreadCount))
-{
-}
-
-DllTransportPlugin::~DllTransportPlugin()
-{
-	m_Impl->Stop();
-}
-
-uint32_t
-DllTransportPlugin::AddRef() const
-{
-	return RefCounted::AddRef();
-}
-
-uint32_t
-DllTransportPlugin::Release() const
-{
-	return RefCounted::Release();
-}
-
-void
-DllTransportPlugin::Initialize(TransportServer* ServerInterface)
-{
-	m_Impl->Start(ServerInterface);
-}
-
-void
-DllTransportPlugin::Shutdown()
-{
-	m_Impl->Stop();
-}
-
-bool
-DllTransportPlugin::IsAvailable()
-{
-	return m_Impl->IsAvailable();
-}
-
-void
-DllTransportPlugin::LoadDll(std::string_view Name)
+DllTransportPlugin*
+CreateDllTransportPlugin()
 {
-	return m_Impl->LoadDll(Name);
+	return new DllTransportPluginImpl;
 }
 
 }  // namespace zen
diff --git a/src/zenhttp/transports/dlltransport.h b/src/zenhttp/transports/dlltransport.h
index 2dccdd0f9..9346a10ce 100644
--- a/src/zenhttp/transports/dlltransport.h
+++ b/src/zenhttp/transports/dlltransport.h
@@ -8,30 +8,19 @@
 
 namespace zen {
 
-class DllTransportPluginImpl;
-
 /** Transport plugin which supports dynamic loading of external transport
  * provider modules
  */
-class DllTransportPlugin : public TransportPlugin, RefCounted
+
+class DllTransportPlugin : public TransportPlugin
 {
 public:
-	DllTransportPlugin(uint16_t BasePort, unsigned int ThreadCount);
-	~DllTransportPlugin();
-
-	virtual uint32_t AddRef() const override;
-	virtual uint32_t Release() const override;
-
-	virtual void Initialize(TransportServer* ServerInterface) override;
-	virtual void Shutdown() override;
-	virtual bool IsAvailable() override;
-
-	void LoadDll(std::string_view Name);
-
-private:
-	std::unique_ptr<DllTransportPluginImpl> m_Impl;
+	virtual void LoadDll(std::string_view Name)														 = 0;
+	virtual void ConfigureDll(std::string_view Name, const char* OptionTag, const char* OptionValue) = 0;
 };
 
+DllTransportPlugin* CreateDllTransportPlugin();
+
 }  // namespace zen
 
 #endif
diff --git a/src/zenhttp/transports/winsocktransport.cpp b/src/zenhttp/transports/winsocktransport.cpp
index ad3302550..2397dd7cf 100644
--- a/src/zenhttp/transports/winsocktransport.cpp
+++ b/src/zenhttp/transports/winsocktransport.cpp
@@ -20,27 +20,6 @@ ZEN_THIRD_PARTY_INCLUDES_END
 
 namespace zen {
 
-class SocketTransportPluginImpl;
-
-class SocketTransportPlugin : public TransportPlugin, RefCounted
-{
-public:
-	SocketTransportPlugin(uint16_t BasePort, unsigned int ThreadCount);
-	~SocketTransportPlugin();
-
-	virtual uint32_t AddRef() const override;
-	virtual uint32_t Release() const override;
-	virtual void	 Initialize(TransportServer* ServerInterface) override;
-	virtual void	 Shutdown() override;
-	virtual bool	 IsAvailable() override;
-
-private:
-	bool					   m_IsOk		 = true;
-	uint16_t				   m_BasePort	 = 0;
-	int						   m_ThreadCount = 0;
-	SocketTransportPluginImpl* m_Impl;
-};
-
 struct SocketTransportConnection : public TransportConnection
 {
 public:
@@ -172,19 +151,23 @@ SocketTransportConnection::Shutdown(bool Receive, bool Transmit)
 
 //////////////////////////////////////////////////////////////////////////
 
-class SocketTransportPluginImpl
+class SocketTransportPluginImpl : public TransportPlugin, RefCounted
 {
 public:
-	SocketTransportPluginImpl(uint16_t BasePort, unsigned int ThreadCount);
+	SocketTransportPluginImpl();
 	~SocketTransportPluginImpl();
 
-	uint16_t Start(uint16_t Port, TransportServer* ServerInterface);
-	void	 Stop();
+	virtual uint32_t AddRef() const override;
+	virtual uint32_t Release() const override;
+	virtual void	 Configure(const char* OptionTag, const char* OptionValue) override;
+	virtual void	 Initialize(TransportServer* ServerInterface) override;
+	virtual void	 Shutdown() override;
+	virtual bool	 IsAvailable() override;
 
 private:
 	TransportServer* m_ServerInterface = nullptr;
-	uint16_t		 m_BasePort		   = 0;
-	int				 m_ThreadCount	   = 0;
+	uint16_t		 m_BasePort		   = 8558;
+	int				 m_ThreadCount	   = 8;
 	bool			 m_IsOk			   = true;
 
 	SOCKET							  m_ListenSocket{};
@@ -193,9 +176,7 @@ private:
 	std::unique_ptr<WorkerThreadPool> m_WorkerThreadpool;
 };
 
-SocketTransportPluginImpl::SocketTransportPluginImpl(uint16_t BasePort, unsigned int ThreadCount)
-: m_BasePort(BasePort)
-, m_ThreadCount(ThreadCount)
+SocketTransportPluginImpl::SocketTransportPluginImpl()
 {
 #	if ZEN_PLATFORM_WINDOWS
 	WSADATA wsaData;
@@ -205,13 +186,11 @@ SocketTransportPluginImpl::SocketTransportPluginImpl(uint16_t BasePort, unsigned
 		WSACleanup();
 	}
 #	endif
-
-	m_WorkerThreadpool = std::make_unique<WorkerThreadPool>(m_ThreadCount, "http_conn");
 }
 
 SocketTransportPluginImpl::~SocketTransportPluginImpl()
 {
-	Stop();
+	Shutdown();
 
 #	if ZEN_PLATFORM_WINDOWS
 	if (m_IsOk)
@@ -221,36 +200,81 @@ SocketTransportPluginImpl::~SocketTransportPluginImpl()
 #	endif
 }
 
-uint16_t
-SocketTransportPluginImpl::Start(uint16_t Port, TransportServer* ServerInterface)
+uint32_t
+SocketTransportPluginImpl::AddRef() const
+{
+	return RefCounted::AddRef();
+}
+
+uint32_t
+SocketTransportPluginImpl::Release() const
+{
+	return RefCounted::Release();
+}
+
+void
+SocketTransportPluginImpl::Configure(const char* OptionTag, const char* OptionValue)
+{
+	using namespace std::literals;
+
+	if (OptionTag == "port"sv)
+	{
+		if (auto PortNum = ParseInt<uint16_t>(OptionValue))
+		{
+			m_BasePort = *PortNum;
+		}
+	}
+	else if (OptionTag == "threads"sv)
+	{
+		if (auto ThreadCount = ParseInt<int>(OptionValue))
+		{
+			m_ThreadCount = *ThreadCount;
+		}
+	}
+	else
+	{
+		// Unknown configuration option
+	}
+}
+
+bool
+SocketTransportPluginImpl::IsAvailable()
 {
-	m_ServerInterface = ServerInterface;
-	m_ListenSocket	  = socket(AF_INET6, SOCK_STREAM, 0);
+	return true;
+}
+
+void
+SocketTransportPluginImpl::Initialize(TransportServer* ServerInterface)
+{
+	m_ServerInterface  = ServerInterface;
+	m_WorkerThreadpool = std::make_unique<WorkerThreadPool>(m_ThreadCount, "http_conn");
+
+	m_ListenSocket = socket(AF_INET6, SOCK_STREAM, 0);
 
 	if (m_ListenSocket == SOCKET_ERROR || m_ListenSocket == INVALID_SOCKET)
 	{
 		ZEN_ERROR("socket creation failed in HTTP plugin server init: {}", WSAGetLastError());
 
-		return 0;
+		return;
 	}
 
 	sockaddr_in6 Server{};
 	Server.sin6_family = AF_INET6;
-	Server.sin6_port   = htons(Port);
+	Server.sin6_port   = htons(m_BasePort);
 	Server.sin6_addr   = in6addr_any;
 
 	if (int Result = bind(m_ListenSocket, (sockaddr*)&Server, sizeof(Server)); Result == SOCKET_ERROR)
 	{
 		ZEN_ERROR("bind call failed in HTTP plugin server init: {}", WSAGetLastError());
 
-		return 0;
+		return;
 	}
 
 	if (int Result = listen(m_ListenSocket, AF_INET6); Result == SOCKET_ERROR)
 	{
 		ZEN_ERROR("listen call failed in HTTP plugin server init: {}", WSAGetLastError());
 
-		return 0;
+		return;
 	}
 
 	m_KeepRunning.test_and_set();
@@ -292,19 +316,20 @@ SocketTransportPluginImpl::Start(uint16_t Port, TransportServer* ServerInterface
 
 		ZEN_INFO("HTTP plugin server accept thread exit");
 	});
-
-	return Port;
 }
 
 void
-SocketTransportPluginImpl::Stop()
+SocketTransportPluginImpl::Shutdown()
 {
 	// TODO: all pending/ongoing work should be drained here as well
 
 	m_KeepRunning.clear();
 
-	closesocket(m_ListenSocket);
-	m_ListenSocket = 0;
+	if (m_ListenSocket)
+	{
+		closesocket(m_ListenSocket);
+		m_ListenSocket = 0;
+	}
 
 	if (m_AcceptThread.joinable())
 	{
@@ -314,52 +339,10 @@ SocketTransportPluginImpl::Stop()
 
 //////////////////////////////////////////////////////////////////////////
 
-SocketTransportPlugin::SocketTransportPlugin(uint16_t BasePort, unsigned int ThreadCount)
-: m_BasePort(BasePort)
-, m_ThreadCount(ThreadCount != 0 ? ThreadCount : Max(std::thread::hardware_concurrency(), 8u))
-, m_Impl(new SocketTransportPluginImpl(BasePort, m_ThreadCount))
-{
-}
-
-SocketTransportPlugin::~SocketTransportPlugin()
-{
-	delete m_Impl;
-}
-
-uint32_t
-SocketTransportPlugin::AddRef() const
-{
-	return RefCounted::AddRef();
-}
-
-uint32_t
-SocketTransportPlugin::Release() const
-{
-	return RefCounted::Release();
-}
-
-void
-SocketTransportPlugin::Initialize(TransportServer* ServerInterface)
-{
-	m_Impl->Start(m_BasePort, ServerInterface);
-}
-
-void
-SocketTransportPlugin::Shutdown()
-{
-	m_Impl->Stop();
-}
-
-bool
-SocketTransportPlugin::IsAvailable()
-{
-	return true;
-}
-
 TransportPlugin*
-CreateSocketTransportPlugin(uint16_t BasePort, unsigned int ThreadCount)
+CreateSocketTransportPlugin()
 {
-	return new SocketTransportPlugin(BasePort, ThreadCount);
+	return new SocketTransportPluginImpl;
 }
 
 }  // namespace zen
diff --git a/src/zenhttp/transports/winsocktransport.h b/src/zenhttp/transports/winsocktransport.h
index 2b2a55aef..59f25d5d3 100644
--- a/src/zenhttp/transports/winsocktransport.h
+++ b/src/zenhttp/transports/winsocktransport.h
@@ -8,7 +8,7 @@
 
 namespace zen {
 
-TransportPlugin* CreateSocketTransportPlugin(uint16_t BasePort, unsigned int ThreadCount);
+TransportPlugin* CreateSocketTransportPlugin();
 
 }  // namespace zen