Client: introduce stream

Implement Stream class instead of NetWorkEngine class.

Stream class encapsulates network connection with simple API:
connect, close, send, recv. It also has status that show blocking
state of I/O.

There must be no logical changes in this patch.

Part of #28

Author: alyapunov

examples/Simple.cpp

@@ -55,7 +55,7 @@ int WAIT_TIMEOUT = 1000; //milliseconds
 //doclabel02-1
 using Buf_t = tnt::Buffer<16 * 1024>;
 #include "../src/Client/LibevNetProvider.hpp"
-using Net_t = LibevNetProvider<Buf_t, NetworkEngine>;
+using Net_t = LibevNetProvider<Buf_t, DefaultStream>;
 //doclabel02-2
 
 //doclabel16-1

src/Client/Connection.hpp

@@ -32,6 +32,7 @@
 
 #include "RequestEncoder.hpp"
 #include "ResponseDecoder.hpp"
+#include "Stream.hpp"
 #include "../Utils/Logger.hpp"
 
 #include <sys/uio.h> //iovec
@@ -80,7 +81,8 @@ struct ConnectionImpl
 	ResponseDecoder<BUFFER> dec;
 	/* Iterator separating decoded and raw data in input buffer. */
 	iterator endDecoded;
-	int socket;
+	/* Network layer of the connection. */
+	typename NetProvider::Stream_t strm;
 	//Several connection wrappers may point to the same implementation.
 	//It is useful to store connection objects in stl containers for example.
 	ssize_t refs;
@@ -94,18 +96,17 @@ struct ConnectionImpl
 template<class BUFFER, class NetProvider>
 ConnectionImpl<BUFFER, NetProvider>::ConnectionImpl(Connector<BUFFER, NetProvider> &conn) :
 	connector(conn), inBuf(), outBuf(), enc(outBuf), dec(inBuf),
-	endDecoded(inBuf.begin()), socket(-1), refs(0)
+	endDecoded(inBuf.begin()), refs(0)
 {
 }
 
 template<class BUFFER, class NetProvider>
 ConnectionImpl<BUFFER, NetProvider>::~ConnectionImpl()
 {
 	assert(refs == 0);
-	if (socket >= 0) {
+	if (!strm.has_status(SS_DEAD)) {
 		Connection<BUFFER, NetProvider> conn(this);
 		connector.close(conn);
-		socket = -1;
 	}
 }
 
@@ -143,6 +144,9 @@ class Connection
 
 	Impl_t *getImpl() { return impl; }
 
+	typename NetProvider::Stream_t &get_strm() { return impl->strm; }
+	const typename NetProvider::Stream_t &get_strm() const { return impl->strm; }
+
 	//Required for storing Connections in hash tables (std::unordered_map)
 	friend bool operator == (const Connection<BUFFER, NetProvider>& lhs,
 				 const Connection<BUFFER, NetProvider>& rhs)
@@ -154,7 +158,8 @@ class Connection
 	friend bool operator < (const Connection<BUFFER, NetProvider>& lhs,
 				const Connection<BUFFER, NetProvider>& rhs)
 	{
-		return lhs.impl->socket < rhs.impl->socket;
+		// TODO: remove dependency on socket.
+		return lhs.get_strm().get_fd() < rhs.get_strm().get_fd();
 	}
 
 	Response<BUFFER> getResponse(rid_t future);
@@ -169,8 +174,6 @@ class Connection
 	void setError(const std::string &msg, int errno_ = 0);
 	ConnectionError& getError();
 	void reset();
-	int getSocket() const;
-	void setSocket(int socket);
 	BUFFER& getInBuf();
 	BUFFER& getOutBuf();
 
@@ -416,20 +419,6 @@ Connection<BUFFER, NetProvider>::reset()
 	impl->error = ConnectionError{};
 }
 
-template<class BUFFER, class NetProvider>
-int
-Connection<BUFFER, NetProvider>::getSocket() const
-{
-	return impl->socket;
-}
-
-template<class BUFFER, class NetProvider>
-void
-Connection<BUFFER, NetProvider>::setSocket(int socket)
-{
-	impl->socket = socket;
-}
-
 template<class BUFFER, class NetProvider>
 BUFFER&
 Connection<BUFFER, NetProvider>::getInBuf()

src/Client/Connector.hpp

@@ -30,22 +30,24 @@
  * SUCH DAMAGE.
  */
 #include "Connection.hpp"
-#include "NetworkEngine.hpp"
+#include "UnixPlainStream.hpp"
 #include "../Utils/Timer.hpp"
 
 #include <set>
 
+using DefaultStream = UnixPlainStream;
+
 /**
  * MacOS does not have epoll so let's use Libev as default network provider.
  */
 #ifdef __linux__
 #include "EpollNetProvider.hpp"
 template<class BUFFER>
-using DefaultNetProvider = EpollNetProvider<BUFFER, NetworkEngine>;
+using DefaultNetProvider = EpollNetProvider<BUFFER, DefaultStream>;
 #else
 #include "LibevNetProvider.hpp"
 template<class BUFFER>
-using DefaultNetProvider = LibevNetProvider<BUFFER, NetworkEngine>;
+using DefaultNetProvider = LibevNetProvider<BUFFER, DefaultStream>;
 #endif
 
 template<class BUFFER, class NetProvider = DefaultNetProvider<BUFFER>>
@@ -58,8 +60,7 @@ class Connector
 	Connector& operator = (const Connector& connector) = delete;
 	//////////////////////////////Main API//////////////////////////////////
 	int connect(Connection<BUFFER, NetProvider> &conn,
-		    const std::string_view& addr, unsigned port,
-		    size_t timeout = DEFAULT_CONNECT_TIMEOUT);
+		    const std::string& addr, unsigned port);
 
 	int wait(Connection<BUFFER, NetProvider> &conn, rid_t future,
 		 int timeout = 0, Response<BUFFER> *result = nullptr);
@@ -76,8 +77,6 @@ class Connector
 	std::set<Connection<BUFFER, NetProvider>> m_ReadyToSend;
 	void close(Connection<BUFFER, NetProvider> &conn);
 private:
-	//Timeout of Connector::connect() method.
-	constexpr static size_t DEFAULT_CONNECT_TIMEOUT = 2;
 	NetProvider m_NetProvider;
 	std::set<Connection<BUFFER, NetProvider>> m_ReadyToDecode;
 };
@@ -95,12 +94,12 @@ Connector<BUFFER, NetProvider>::~Connector()
 template<class BUFFER, class NetProvider>
 int
 Connector<BUFFER, NetProvider>::connect(Connection<BUFFER, NetProvider> &conn,
-					const std::string_view& addr,
-					unsigned port, size_t timeout)
+					const std::string& addr,
+					unsigned port)
 {
 	//Make sure that connection is not yet established.
-	assert(conn.getSocket() < 0);
-	if (m_NetProvider.connect(conn, addr, port, timeout) != 0) {
+	assert(conn.get_strm().has_status(SS_DEAD));
+	if (m_NetProvider.connect(conn, addr, port) != 0) {
 		LOG_ERROR("Failed to connect to ", addr, ':', port);
 		return -1;
 	}
@@ -112,9 +111,8 @@ template<class BUFFER, class NetProvider>
 void
 Connector<BUFFER, NetProvider>::close(Connection<BUFFER, NetProvider> &conn)
 {
-	assert(conn.getSocket() >= 0);
+	assert(!conn.get_strm().has_status(SS_DEAD));
 	m_NetProvider.close(conn);
-	conn.setSocket(-1);
 }
 
 template<class BUFFER, class NetProvider>