1 files changed, 331 insertions, 0 deletions

diff --git a/src/OSSupport/TCPLinkImpl.cpp b/src/OSSupport/TCPLinkImpl.cpp
new file mode 100644
index 000000000..b4cefa60c
--- /dev/null
+++ b/src/OSSupport/TCPLinkImpl.cpp
@@ -0,0 +1,331 @@
+
+// TCPLinkImpl.cpp
+
+// Implements the cTCPLinkImpl class implementing the TCP link functionality
+
+#include "Globals.h"
+#include "TCPLinkImpl.h"
+#include "NetworkSingleton.h"
+#include "ServerHandleImpl.h"
+
+
+
+
+
+////////////////////////////////////////////////////////////////////////////////
+// cTCPLinkImpl:
+
+cTCPLinkImpl::cTCPLinkImpl(cTCPLink::cCallbacksPtr a_LinkCallbacks):
+	super(a_LinkCallbacks),
+	m_BufferEvent(bufferevent_socket_new(cNetworkSingleton::Get().GetEventBase(), -1, BEV_OPT_CLOSE_ON_FREE))
+{
+}
+
+
+
+
+
+cTCPLinkImpl::cTCPLinkImpl(evutil_socket_t a_Socket, cTCPLink::cCallbacksPtr a_LinkCallbacks, cServerHandleImplPtr a_Server, const sockaddr * a_Address, socklen_t a_AddrLen):
+	super(a_LinkCallbacks),
+	m_BufferEvent(bufferevent_socket_new(cNetworkSingleton::Get().GetEventBase(), a_Socket, BEV_OPT_CLOSE_ON_FREE)),
+	m_Server(a_Server)
+{
+	// Update the endpoint addresses:
+	UpdateLocalAddress();
+	UpdateAddress(a_Address, a_AddrLen, m_RemoteIP, m_RemotePort);
+}
+
+
+
+
+
+cTCPLinkImpl::~cTCPLinkImpl()
+{
+	bufferevent_free(m_BufferEvent);
+}
+
+
+
+
+
+cTCPLinkImplPtr cTCPLinkImpl::Connect(const AString & a_Host, UInt16 a_Port, cTCPLink::cCallbacksPtr a_LinkCallbacks, cNetwork::cConnectCallbacksPtr a_ConnectCallbacks)
+{
+	ASSERT(a_LinkCallbacks != nullptr);
+	ASSERT(a_ConnectCallbacks != nullptr);
+
+	// Create a new link:
+	cTCPLinkImplPtr res{new cTCPLinkImpl(a_LinkCallbacks)};  // Cannot use std::make_shared here, constructor is not accessible
+	res->m_ConnectCallbacks = a_ConnectCallbacks;
+	cNetworkSingleton::Get().AddLink(res);
+	res->m_Callbacks->OnLinkCreated(res);
+	res->Enable(res);
+
+	// If a_Host is an IP address, schedule a connection immediately:
+	sockaddr_storage sa;
+	int salen = static_cast<int>(sizeof(sa));
+	if (evutil_parse_sockaddr_port(a_Host.c_str(), reinterpret_cast<sockaddr *>(&sa), &salen) == 0)
+	{
+		// Insert the correct port:
+		if (sa.ss_family == AF_INET6)
+		{
+			reinterpret_cast<sockaddr_in6 *>(&sa)->sin6_port = htons(a_Port);
+		}
+		else
+		{
+			reinterpret_cast<sockaddr_in *>(&sa)->sin_port = htons(a_Port);
+		}
+
+		// Queue the connect request:
+		if (bufferevent_socket_connect(res->m_BufferEvent, reinterpret_cast<sockaddr *>(&sa), salen) == 0)
+		{
+			// Success
+			return res;
+		}
+		// Failure
+		cNetworkSingleton::Get().RemoveLink(res.get());
+		return nullptr;
+	}
+
+	// a_Host is a hostname, connect after a lookup:
+	if (bufferevent_socket_connect_hostname(res->m_BufferEvent, cNetworkSingleton::Get().GetDNSBase(), AF_UNSPEC, a_Host.c_str(), a_Port) == 0)
+	{
+		// Success
+		return res;
+	}
+	// Failure
+	cNetworkSingleton::Get().RemoveLink(res.get());
+	return nullptr;
+}
+
+
+
+
+
+void cTCPLinkImpl::Enable(cTCPLinkImplPtr a_Self)
+{
+	// Take hold of a shared copy of self, to keep as long as the callbacks are coming:
+	m_Self = a_Self;
+
+	// Set the LibEvent callbacks and enable processing:
+	bufferevent_setcb(m_BufferEvent, ReadCallback, nullptr, EventCallback, this);
+	bufferevent_enable(m_BufferEvent, EV_READ | EV_WRITE);
+}
+
+
+
+
+
+bool cTCPLinkImpl::Send(const void * a_Data, size_t a_Length)
+{
+	return (bufferevent_write(m_BufferEvent, a_Data, a_Length) == 0);
+}
+
+
+
+
+
+void cTCPLinkImpl::Shutdown(void)
+{
+	#ifdef _WIN32
+		shutdown(bufferevent_getfd(m_BufferEvent), SD_SEND);
+	#else
+		shutdown(bufferevent_getfd(m_BufferEvent), SHUT_WR);
+	#endif
+	bufferevent_disable(m_BufferEvent, EV_WRITE);
+}
+
+
+
+
+
+void cTCPLinkImpl::Close(void)
+{
+	// Disable all events on the socket, but keep it alive:
+	bufferevent_disable(m_BufferEvent, EV_READ | EV_WRITE);
+	if (m_Server == nullptr)
+	{
+		cNetworkSingleton::Get().RemoveLink(this);
+	}
+	else
+	{
+		m_Server->RemoveLink(this);
+	}
+	m_Self.reset();
+}
+
+
+
+
+
+
+void cTCPLinkImpl::ReadCallback(bufferevent * a_BufferEvent, void * a_Self)
+{
+	ASSERT(a_Self != nullptr);
+	cTCPLinkImpl * Self = static_cast<cTCPLinkImpl *>(a_Self);
+	ASSERT(Self->m_Callbacks != nullptr);
+
+	// Read all the incoming data, in 1024-byte chunks:
+	char data[1024];
+	size_t length;
+	while ((length = bufferevent_read(a_BufferEvent, data, sizeof(data))) > 0)
+	{
+		Self->m_Callbacks->OnReceivedData(data, length);
+	}
+}
+
+
+
+
+
+void cTCPLinkImpl::EventCallback(bufferevent * a_BufferEvent, short a_What, void * a_Self)
+{
+	ASSERT(a_Self != nullptr);
+	cTCPLinkImplPtr Self = static_cast<cTCPLinkImpl *>(a_Self)->m_Self;
+
+	// If an error is reported, call the error callback:
+	if (a_What & BEV_EVENT_ERROR)
+	{
+		// Choose the proper callback to call based on whether we were waiting for connection or not:
+		int err = EVUTIL_SOCKET_ERROR();
+		if (Self->m_ConnectCallbacks != nullptr)
+		{
+			if (err == 0)
+			{
+				// This could be a DNS failure
+				err = bufferevent_socket_get_dns_error(a_BufferEvent);
+			}
+			Self->m_ConnectCallbacks->OnError(err, evutil_socket_error_to_string(err));
+		}
+		else
+		{
+			Self->m_Callbacks->OnError(err, evutil_socket_error_to_string(err));
+			if (Self->m_Server == nullptr)
+			{
+				cNetworkSingleton::Get().RemoveLink(Self.get());
+			}
+			else
+			{
+				Self->m_Server->RemoveLink(Self.get());
+			}
+		}
+		Self->m_Self.reset();
+		return;
+	}
+
+	// Pending connection succeeded, call the connection callback:
+	if (a_What & BEV_EVENT_CONNECTED)
+	{
+		if (Self->m_ConnectCallbacks != nullptr)
+		{
+			Self->m_ConnectCallbacks->OnConnected(*Self);
+			// Reset the connect callbacks so that later errors get reported through the link callbacks:
+			Self->m_ConnectCallbacks.reset();
+			return;
+		}
+		Self->UpdateLocalAddress();
+		Self->UpdateRemoteAddress();
+	}
+
+	// If the connection has been closed, call the link callback and remove the connection:
+	if (a_What & BEV_EVENT_EOF)
+	{
+		Self->m_Callbacks->OnRemoteClosed();
+		if (Self->m_Server != nullptr)
+		{
+			Self->m_Server->RemoveLink(Self.get());
+		}
+		else
+		{
+			cNetworkSingleton::Get().RemoveLink(Self.get());
+		}
+		Self->m_Self.reset();
+		return;
+	}
+	
+	// Unknown event, report it:
+	LOGWARNING("cTCPLinkImpl: Unhandled LibEvent event %d (0x%x)", a_What, a_What);
+	ASSERT(!"cTCPLinkImpl: Unhandled LibEvent event");
+}
+
+
+
+
+
+void cTCPLinkImpl::UpdateAddress(const sockaddr * a_Address, socklen_t a_AddrLen, AString & a_IP, UInt16 & a_Port)
+{
+	// Based on the family specified in the address, use the correct datastructure to convert to IP string:
+	char IP[128];
+	switch (a_Address->sa_family)
+	{
+		case AF_INET:  // IPv4:
+		{
+			const sockaddr_in * sin = reinterpret_cast<const sockaddr_in *>(a_Address);
+			evutil_inet_ntop(AF_INET, &(sin->sin_addr), IP, sizeof(IP));
+			a_Port = ntohs(sin->sin_port);
+			break;
+		}
+		case AF_INET6:  // IPv6
+		{
+			const sockaddr_in6 * sin = reinterpret_cast<const sockaddr_in6 *>(a_Address);
+			evutil_inet_ntop(AF_INET6, &(sin->sin6_addr), IP, sizeof(IP));
+			a_Port = ntohs(sin->sin6_port);
+			break;
+		}
+
+		default:
+		{
+			LOGWARNING("%s: Unknown socket address family: %d", __FUNCTION__, a_Address->sa_family);
+			ASSERT(!"Unknown socket address family");
+			break;
+		}
+	}
+	a_IP.assign(IP);
+}
+
+
+
+
+
+void cTCPLinkImpl::UpdateLocalAddress(void)
+{
+	sockaddr_storage sa;
+	socklen_t salen = static_cast<socklen_t>(sizeof(sa));
+	getsockname(bufferevent_getfd(m_BufferEvent), reinterpret_cast<sockaddr *>(&sa), &salen);
+	UpdateAddress(reinterpret_cast<const sockaddr *>(&sa), salen, m_LocalIP, m_LocalPort);
+}
+
+
+
+
+
+void cTCPLinkImpl::UpdateRemoteAddress(void)
+{
+	sockaddr_storage sa;
+	socklen_t salen = static_cast<socklen_t>(sizeof(sa));
+	getpeername(bufferevent_getfd(m_BufferEvent), reinterpret_cast<sockaddr *>(&sa), &salen);
+	UpdateAddress(reinterpret_cast<const sockaddr *>(&sa), salen, m_RemoteIP, m_RemotePort);
+}
+
+
+
+
+
+////////////////////////////////////////////////////////////////////////////////
+// cNetwork API:
+
+bool cNetwork::Connect(
+	const AString & a_Host,
+	UInt16 a_Port,
+	cNetwork::cConnectCallbacksPtr a_ConnectCallbacks,
+	cTCPLink::cCallbacksPtr a_LinkCallbacks
+)
+{
+	// Add a connection request to the queue:
+	cTCPLinkImplPtr Conn = cTCPLinkImpl::Connect(a_Host, a_Port, a_LinkCallbacks, a_ConnectCallbacks);
+	return (Conn != nullptr);
+}
+
+
+
+
+