//
// Function: DerefSocketContext
//
// Description:
// This routine holds the LSP critical section and decrements the ref count
// by one. It also checks if the socket has been closed while holding the
// ref count. This can happen if two threads are accessing a socket simultaneously
// and one calls closesocket. We don't want to remove the context from under
// the second thread so it is marked as closing instead.
//
void
DerefSocketContext(
SOCK_INFO *context,
int *lpErrno
)
{
LONG newval;
int ret = NO_ERROR;
EnterCriticalSection(&GlobalVars::gCriticalSection);
// Decrement the ref count and see if someone closed this socket (from another thread)
newval = InterlockedDecrement(&context->RefCount);
if ( ( 0 == newval ) &&
( 0 == context->dwOutstandingAsync ) &&
( TRUE == context->bClosing )
)
{
ASSERT( GlobalVars::gMainUpCallTable.lpWPUCloseSocketHandle );
// Socket has been closed so close the handle and free associated resources
ret = GlobalVars::gMainUpCallTable.lpWPUCloseSocketHandle(context->LayeredSocket, lpErrno);
if ( SOCKET_ERROR == ret )
{
dbgprint("DerefSocketContext: WPUCloseSocketHandle() failed: %d", *lpErrno);
}
context->LayeredSocket = INVALID_SOCKET;
RemoveSocketInfo(context->Provider, context);
dbgprint("Closing socket %d Bytes Sent [%lu] Bytes Recv [%lu]",
context->LayeredSocket, context->BytesSent, context->BytesRecv);
FreeSockInfo( context );
context = NULL;
}
LeaveCriticalSection( &GlobalVars::gCriticalSection );
}
int main(int argc, char *argv[])
{
int retval;
InitializeCriticalSection(&cs);
// 윈속 초기화
WSADATA wsa;
if(WSAStartup(MAKEWORD(2,2), &wsa) != 0) return 1;
// socket()
SOCKET listen_sock = socket(AF_INET, SOCK_STREAM, 0);
if(listen_sock == INVALID_SOCKET) err_quit("socket()");
// bind()
SOCKADDR_IN serveraddr;
ZeroMemory(&serveraddr, sizeof(serveraddr));
serveraddr.sin_family = AF_INET;
serveraddr.sin_addr.s_addr = htonl(INADDR_ANY);
serveraddr.sin_port = htons(SERVERPORT);
retval = bind(listen_sock, (SOCKADDR *)&serveraddr, sizeof(serveraddr));
if(retval == SOCKET_ERROR) err_quit("bind()");
// listen()
retval = listen(listen_sock, SOMAXCONN);
if(retval == SOCKET_ERROR) err_quit("listen()");
// 더미(dummy) 이벤트 객체 생성
WSAEVENT hEvent = WSACreateEvent();
if(hEvent == WSA_INVALID_EVENT)
err_quit("WSACreateEvent()");
EventArray[nTotalSockets++] = hEvent;
// 스레드 생성
HANDLE hThread = CreateThread(NULL, 0, WorkerThread, NULL, 0, NULL);
if(hThread == NULL) return 1;
CloseHandle(hThread);
// 데이터 통신에 사용할 변수
SOCKET client_sock;
SOCKADDR_IN clientaddr;
int addrlen;
DWORD recvbytes, flags;
while(1){
// accept()
addrlen = sizeof(clientaddr);
client_sock = accept(listen_sock, (SOCKADDR *)&clientaddr, &addrlen);
if(client_sock == INVALID_SOCKET){
err_display("accept()");
break;
}
printf("\n[TCP 서버] 클라이언트 접속: IP 주소=%s, 포트 번호=%d\n",
inet_ntoa(clientaddr.sin_addr), ntohs(clientaddr.sin_port));
// 소켓 정보 추가
if(AddSocketInfo(client_sock) == FALSE){
closesocket(client_sock);
printf("[TCP 서버] 클라이언트 종료: IP 주소=%s, 포트 번호=%d\n",
inet_ntoa(clientaddr.sin_addr), ntohs(clientaddr.sin_port));
continue;
}
// 비동기 입출력 시작
SOCKETINFO *ptr = SocketInfoArray[nTotalSockets-1];
flags = 0;
retval = WSARecv(ptr->sock, &ptr->wsabuf, 1, &recvbytes,
&flags, &ptr->overlapped, NULL);
if(retval == SOCKET_ERROR){
if(WSAGetLastError() != WSA_IO_PENDING){
err_display("WSARecv()");
RemoveSocketInfo(nTotalSockets-1);
continue;
}
}
// 소켓의 개수(nTotalSockets) 변화를 알림
WSASetEvent(EventArray[0]);
}
// 윈속 종료
WSACleanup();
DeleteCriticalSection(&cs);
return 0;
}
// 비동기 입출력 처리 함수
DWORD WINAPI WorkerThread(LPVOID arg)
{
int retval;
while(1){
// 이벤트 객체 관찰
DWORD index = WSAWaitForMultipleEvents(nTotalSockets,
EventArray, FALSE, WSA_INFINITE, FALSE);
if(index == WSA_WAIT_FAILED) continue;
index -= WSA_WAIT_EVENT_0;
WSAResetEvent(EventArray[index]);
if(index == 0) continue;
// 클라이언트 정보 얻기
SOCKETINFO *ptr = SocketInfoArray[index];
SOCKADDR_IN clientaddr;
int addrlen = sizeof(clientaddr);
getpeername(ptr->sock, (SOCKADDR *)&clientaddr, &addrlen);
// 비동기 입출력 결과 확인
DWORD cbTransferred, flags;
retval = WSAGetOverlappedResult(ptr->sock, &ptr->overlapped,
&cbTransferred, FALSE, &flags);
if(retval == FALSE || cbTransferred == 0){
RemoveSocketInfo(index);
printf("[TCP 서버] 클라이언트 종료: IP 주소=%s, 포트 번호=%d\n",
inet_ntoa(clientaddr.sin_addr), ntohs(clientaddr.sin_port));
continue;
}
// 데이터 전송량 갱신
if(ptr->recvbytes == 0){
ptr->recvbytes = cbTransferred;
ptr->sendbytes = 0;
// 받은 데이터 출력
ptr->buf[ptr->recvbytes] = '\0';
printf("[TCP/%s:%d] %s\n", inet_ntoa(clientaddr.sin_addr),
ntohs(clientaddr.sin_port), ptr->buf);
}
else{
ptr->sendbytes += cbTransferred;
}
if(ptr->recvbytes > ptr->sendbytes){
// 데이터 보내기
ZeroMemory(&ptr->overlapped, sizeof(ptr->overlapped));
ptr->overlapped.hEvent = EventArray[index];
ptr->wsabuf.buf = ptr->buf + ptr->sendbytes;
ptr->wsabuf.len = ptr->recvbytes - ptr->sendbytes;
DWORD sendbytes;
retval = WSASend(ptr->sock, &ptr->wsabuf, 1, &sendbytes,
0, &ptr->overlapped, NULL);
if(retval == SOCKET_ERROR){
if(WSAGetLastError() != WSA_IO_PENDING){
err_display("WSASend()");
}
continue;
}
}
else{
ptr->recvbytes = 0;
// 데이터 받기
ZeroMemory(&ptr->overlapped, sizeof(ptr->overlapped));
ptr->overlapped.hEvent = EventArray[index];
ptr->wsabuf.buf = ptr->buf;
ptr->wsabuf.len = BUFSIZE;
DWORD recvbytes;
flags = 0;
retval = WSARecv(ptr->sock, &ptr->wsabuf, 1, &recvbytes,
&flags, &ptr->overlapped, NULL);
if(retval == SOCKET_ERROR){
if(WSAGetLastError() != WSA_IO_PENDING){
err_display("WSARecv()");
}
continue;
}
}
}
}
int main(int argc, char *argv[])
{
int retval;
// 윈속 초기화
WSADATA wsa;
if(WSAStartup(MAKEWORD(2,2), &wsa) != 0)
return 1;
// socket()
SOCKET listen_sock = socket(AF_INET, SOCK_STREAM, 0);
if(listen_sock == INVALID_SOCKET) err_quit("socket()");
// bind()
SOCKADDR_IN serveraddr;
ZeroMemory(&serveraddr, sizeof(serveraddr));
serveraddr.sin_family = AF_INET;
serveraddr.sin_addr.s_addr = htonl(INADDR_ANY);
serveraddr.sin_port = htons(SERVERPORT);
retval = bind(listen_sock, (SOCKADDR *)&serveraddr, sizeof(serveraddr));
if(retval == SOCKET_ERROR) err_quit("bind()");
// listen()
retval = listen(listen_sock, SOMAXCONN);
if(retval == SOCKET_ERROR) err_quit("listen()");
// 넌블로킹 소켓으로 전환
u_long on = 1;
retval = ioctlsocket(listen_sock, FIONBIO, &on);
if(retval == SOCKET_ERROR) err_display("ioctlsocket()");
// 데이터 통신에 사용할 변수
FD_SET rset, wset;
SOCKET client_sock;
SOCKADDR_IN clientaddr;
int addrlen, i;
while(1){
// 소켓 셋 초기화
FD_ZERO(&rset);
FD_ZERO(&wset);
FD_SET(listen_sock, &rset);
for(i=0; i<nTotalSockets; i++){
if(SocketInfoArray[i]->recvbytes > SocketInfoArray[i]->sendbytes)
FD_SET(SocketInfoArray[i]->sock, &wset);
else
FD_SET(SocketInfoArray[i]->sock, &rset);
}
// select()
retval = select(0, &rset, &wset, NULL, NULL);
if(retval == SOCKET_ERROR) err_quit("select()");
// 소켓 셋 검사(1): 클라이언트 접속 수용
if(FD_ISSET(listen_sock, &rset)){
addrlen = sizeof(clientaddr);
client_sock = accept(listen_sock, (SOCKADDR *)&clientaddr, &addrlen);
if(client_sock == INVALID_SOCKET){
err_display("accept()");
}
else{
printf("\n[TCP 서버] 클라이언트 접속: IP 주소=%s, 포트 번호=%d\n",
inet_ntoa(clientaddr.sin_addr), ntohs(clientaddr.sin_port));
// 소켓 정보 추가
AddSocketInfo(client_sock);
}
}
// 소켓 셋 검사(2): 데이터 통신
for(i=0; i<nTotalSockets; i++){
SOCKETINFO *ptr = SocketInfoArray[i];
if(FD_ISSET(ptr->sock, &rset)){
// 데이터 받기
retval = recv(ptr->sock, ptr->buf, BUFSIZE, 0);
if(retval == SOCKET_ERROR){
err_display("recv()");
RemoveSocketInfo(i);
continue;
}
else if(retval == 0){
RemoveSocketInfo(i);
continue;
}
ptr->recvbytes = retval;
// 받은 데이터 출력
addrlen = sizeof(clientaddr);
getpeername(ptr->sock, (SOCKADDR *)&clientaddr, &addrlen);
ptr->buf[retval] = '\0';
printf("[TCP/%s:%d] %s\n", inet_ntoa(clientaddr.sin_addr),
ntohs(clientaddr.sin_port), ptr->buf);
}
if(FD_ISSET(ptr->sock, &wset)){
// 데이터 보내기
retval = send(ptr->sock, ptr->buf + ptr->sendbytes,
ptr->recvbytes - ptr->sendbytes, 0);
if(retval == SOCKET_ERROR){
err_display("send()");
RemoveSocketInfo(i);
continue;
}
ptr->sendbytes += retval;
if(ptr->recvbytes == ptr->sendbytes){
ptr->recvbytes = ptr->sendbytes = 0;
}
}
}
}
// 윈속 종료
WSACleanup();
return 0;
}
