(C++ : IOCP-34) Socket Utils

int main()
{
    // SocketUtils라는 전역의 클래스를 이용하여
	// 아래와 같이 쓰고싶어서 만든다
	SOCKET socket = SocketUtils::CreateSocket();
	SocketUtils::BindAnyAddress(socket, 7777);
	SocketUtils::Listen(socket);

	SOCKET clientSocket = ::accept(socket, nullptr, nullptr);

	cout << "Client Connected!" << endl; 

	while (true)
	{

	}

	GThreadManager->Join();
}

// SocketUtils의 초기화/삭제는 아래와 같이 글로벌로 관리
class CoreGlobal
{
public:
	CoreGlobal()
	{
		GThreadManager = new ThreadManager();
		GMemory = new Memory();
		GDeadLockProfiler = new DeadLockProfiler();
		SocketUtils::Init();
	}

	~CoreGlobal()
	{
		delete GThreadManager;
		delete GMemory;
		delete GDeadLockProfiler;
		SocketUtils::Clear();
	}
} GCoreGlobal;

class NetAddress
{
public:
	NetAddress() = default;
	NetAddress(SOCKADDR_IN sockAddr);
	NetAddress(wstring ip, uint16 port);

	SOCKADDR_IN&	GetSockAddr() { return _sockAddr; }
	wstring			GetIpAddress();
	uint16			GetPort() { return ::ntohs(_sockAddr.sin_port); }

public:
	static IN_ADDR	Ip2Address(const WCHAR* ip);

private:
	SOCKADDR_IN		_sockAddr = {};
};

NetAddress::NetAddress(SOCKADDR_IN sockAddr) : _sockAddr(sockAddr)
{
}

NetAddress::NetAddress(wstring ip, uint16 port)
{
	::memset(&_sockAddr, 0, sizeof(_sockAddr));
	_sockAddr.sin_family = AF_INET;
	_sockAddr.sin_addr = Ip2Address(ip.c_str());
	_sockAddr.sin_port = ::htons(port);
}

wstring NetAddress::GetIpAddress()
{
	WCHAR buffer[100];
	::InetNtopW(AF_INET, &_sockAddr.sin_addr, buffer, len32(buffer));
	return wstring(buffer);
}

IN_ADDR NetAddress::Ip2Address(const WCHAR* ip)
{
	IN_ADDR address;
	::InetPtonW(AF_INET, ip, &address);
	return address;
}

#pragma once
#include "NetAddress.h"

/*----------------
	SocketUtils
-----------------*/

class SocketUtils
{
public:
	// 함수포인터 사용의 목적은 IOCP Socket의 Connect, Disconnect, Accept의 callback(event)를 받고싶다
	static LPFN_CONNECTEX		ConnectEx;
	static LPFN_DISCONNECTEX	DisconnectEx;
	static LPFN_ACCEPTEX		AcceptEx;

public:
	static void Init();
	static void Clear();

	static bool BindWindowsFunction(SOCKET socket, GUID guid, LPVOID* fn);
	static SOCKET CreateSocket();

	static bool SetLinger(SOCKET socket, uint16 onoff, uint16 linger);
	static bool SetReuseAddress(SOCKET socket, bool flag);
	static bool SetRecvBufferSize(SOCKET socket, int32 size);
	static bool SetSendBufferSize(SOCKET socket, int32 size);
	static bool SetTcpNoDelay(SOCKET socket, bool flag);
	static bool SetUpdateAcceptSocket(SOCKET socket, SOCKET listenSocket);

	static bool Bind(SOCKET socket, NetAddress netAddr);
	static bool BindAnyAddress(SOCKET socket, uint16 port);
	static bool Listen(SOCKET socket, int32 backlog = SOMAXCONN);
	static void Close(SOCKET& socket);
};

template<typename T>
static inline bool SetSockOpt(SOCKET socket, int32 level, int32 optName, T optVal)
{
	return SOCKET_ERROR != ::setsockopt(socket, level, optName, reinterpret_cast<char*>(&optVal), sizeof(T));
}

#include "pch.h"
#include "SocketUtils.h"

/*----------------
	SocketUtils
-----------------*/

LPFN_CONNECTEX		SocketUtils::ConnectEx = nullptr;
LPFN_DISCONNECTEX	SocketUtils::DisconnectEx = nullptr;
LPFN_ACCEPTEX		SocketUtils::AcceptEx = nullptr;

void SocketUtils::Init()
{
	WSADATA wsaData;
	ASSERT_CRASH(::WSAStartup(MAKEWORD(2, 2), OUT &wsaData) == 0);
	
	/* 런타임에 주소 얻어오는 API */
	// connect, disconnect, accept 함수주소를 받아온다
	SOCKET dummySocket = CreateSocket();
	ASSERT_CRASH(BindWindowsFunction(dummySocket, WSAID_CONNECTEX, reinterpret_cast<LPVOID*>(&ConnectEx)));
	ASSERT_CRASH(BindWindowsFunction(dummySocket, WSAID_DISCONNECTEX, reinterpret_cast<LPVOID*>(&DisconnectEx)));
	ASSERT_CRASH(BindWindowsFunction(dummySocket, WSAID_ACCEPTEX, reinterpret_cast<LPVOID*>(&AcceptEx)));
	Close(dummySocket);
}

void SocketUtils::Clear()
{
	::WSACleanup();
}

bool SocketUtils::BindWindowsFunction(SOCKET socket, GUID guid, LPVOID* fn)
{
	DWORD bytes = 0;
	return SOCKET_ERROR != ::WSAIoctl(socket,  // 임시로 더미소켓을 사용함.
							SIO_GET_EXTENSION_FUNCTION_POINTER, 
							&guid, sizeof(guid), fn, sizeof(*fn), OUT & bytes, NULL, NULL);
}

SOCKET SocketUtils::CreateSocket()
{
	return ::WSASocket(AF_INET, SOCK_STREAM, IPPROTO_TCP, NULL, 0, WSA_FLAG_OVERLAPPED);
}

bool SocketUtils::SetLinger(SOCKET socket, uint16 onoff, uint16 linger)
{
	LINGER option;
	option.l_onoff = onoff;
	option.l_linger = linger;
	return SetSockOpt(socket, SOL_SOCKET, SO_LINGER, option);
}

bool SocketUtils::SetReuseAddress(SOCKET socket, bool flag)
{
	return SetSockOpt(socket, SOL_SOCKET, SO_REUSEADDR, flag);
}

bool SocketUtils::SetRecvBufferSize(SOCKET socket, int32 size)
{
	return SetSockOpt(socket, SOL_SOCKET, SO_RCVBUF, size);
}

bool SocketUtils::SetSendBufferSize(SOCKET socket, int32 size)
{
	return SetSockOpt(socket, SOL_SOCKET, SO_SNDBUF, size);
}

bool SocketUtils::SetTcpNoDelay(SOCKET socket, bool flag)
{
	return SetSockOpt(socket, SOL_SOCKET, TCP_NODELAY, flag);
}

// ListenSocket의 특성을 ClientSocket에 그대로 적용
bool SocketUtils::SetUpdateAcceptSocket(SOCKET socket, SOCKET listenSocket)
{
	return SetSockOpt(socket, SOL_SOCKET, SO_UPDATE_ACCEPT_CONTEXT, listenSocket);
}

bool SocketUtils::Bind(SOCKET socket, NetAddress netAddr)
{
	return SOCKET_ERROR != ::bind(socket, reinterpret_cast<const SOCKADDR*>(&netAddr.GetSockAddr()), sizeof(SOCKADDR_IN));
}

bool SocketUtils::BindAnyAddress(SOCKET socket, uint16 port)
{
	SOCKADDR_IN myAddress;
	myAddress.sin_family = AF_INET;
	myAddress.sin_addr.s_addr = ::htonl(INADDR_ANY);
	myAddress.sin_port = ::htons(port);

	return SOCKET_ERROR != ::bind(socket, reinterpret_cast<const SOCKADDR*>(&myAddress), sizeof(myAddress));
}

bool SocketUtils::Listen(SOCKET socket, int32 backlog)
{
	return SOCKET_ERROR != ::listen(socket, backlog);
}

void SocketUtils::Close(SOCKET& socket)
{
	if (socket != INVALID_SOCKET)
		::closesocket(socket);
	socket = INVALID_SOCKET;
}