不用多线程,如何处理多个socket

[cyberkit]

很多代码都是用多线程处理多个socket,虽然很方便,但是如果socket很多,多线程必然会使效率降低
如果不用多线程该怎么做,windows网络编程里的代码过于省略,请各位贴几个完整的代码看看好吗?谢谢

[bluekite]

關注一下！

[lifengice0706]

使用select模式，代码在csdn或google找。

[nuaawenlin]

WSAAsyncSelect()，异步选择模式

[贵子潘]

实质上还是多线程...

[hejie19q2004]

#include <winsock2.h>
#include <windows.h>
#include <stdio.h>
#include <conio.h>

#define PORT 5150
#define DATA_BUFSIZE 8192

typedef struct _SOCKET_INFORMATION {
BOOL RecvPosted;
CHAR Buffer[DATA_BUFSIZE];
WSABUF DataBuf;
SOCKET Socket;
DWORD BytesSEND;
DWORD BytesRECV;
_SOCKET_INFORMATION *Next;
} SOCKET_INFORMATION, * LPSOCKET_INFORMATION;

#define WM_SOCKET (WM_USER + 1)

void CreateSocketInformation(SOCKET s);
LPSOCKET_INFORMATION GetSocketInformation(SOCKET s);
void FreeSocketInformation(SOCKET s);

HWND MakeWorkerWindow(void);
LRESULT CALLBACK WindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam);

LPSOCKET_INFORMATION SocketInfoList;

void main(void)
{
MSG msg;
DWORD Ret;
SOCKET Listen;
SOCKADDR_IN InternetAddr;
HWND Window;
WSADATA wsaData;

if ((Window = MakeWorkerWindow()) == NULL)
return;

// Prepare echo server

if ((Ret = WSAStartup(0x0202, &wsaData)) != 0)
{
printf("WSAStartup failed with error %d\n", Ret);
return;
}

if ((Listen = socket (PF_INET, SOCK_STREAM, 0)) == INVALID_SOCKET)
{
printf("socket() failed with error %d\n", WSAGetLastError());
return;
}

WSAAsyncSelect(Listen, Window, WM_SOCKET, FD_ACCEPT|FD_CLOSE);

InternetAddr.sin_family = AF_INET;
InternetAddr.sin_addr.s_addr = htonl(INADDR_ANY);
InternetAddr.sin_port = htons(PORT);

if (bind(Listen, (PSOCKADDR) &InternetAddr, sizeof(InternetAddr)) == SOCKET_ERROR)
{
printf("bind() failed with error %d\n", WSAGetLastError());
return;
}

if (listen(Listen, 5))
{
printf("listen() failed with error %d\n", WSAGetLastError());
return;
}

// Translate and dispatch window messages for the application thread

[hejie19q2004]

while(Ret = GetMessage(&msg, NULL, 0, 0))
{
if (Ret == -1)
{
printf("GetMessage() failed with error %d\n", GetLastError());
return;
}

TranslateMessage(&msg);
DispatchMessage(&msg);
}
}


LRESULT CALLBACK WindowProc(HWND hwnd, UINT uMsg, WPARAM wParam, LPARAM lParam)
{
SOCKET Accept;
LPSOCKET_INFORMATION SocketInfo;
DWORD RecvBytes, SendBytes;
DWORD Flags;

if (uMsg == WM_SOCKET)
{
if (WSAGETSELECTERROR(lParam))
{
printf("Socket failed with error %d\n", WSAGETSELECTERROR(lParam));
FreeSocketInformation(wParam);
}
else
{
switch(WSAGETSELECTEVENT(lParam))
{
case FD_ACCEPT:

if ((Accept = accept(wParam, NULL, NULL)) == INVALID_SOCKET)
{
printf("accept() failed with error %d\n", WSAGetLastError());
break;
}

// Create a socket information structure to associate with the
// socket for processing I/O.

CreateSocketInformation(Accept);

printf("Socket number %d connected\n", Accept);

WSAAsyncSelect(Accept, hwnd, WM_SOCKET, FD_READ|FD_WRITE|FD_CLOSE);

break;

case FD_READ:

SocketInfo = GetSocketInformation(wParam);

// Read data only if the receive buffer is empty.

if (SocketInfo->BytesRECV != 0)
{
SocketInfo->RecvPosted = TRUE;
return 0;
}
else
{
SocketInfo->DataBuf.buf = SocketInfo->Buffer;
SocketInfo->DataBuf.len = DATA_BUFSIZE;

Flags = 0;
if (WSARecv(SocketInfo->Socket, &(SocketInfo->DataBuf), 1, &RecvBytes,
&Flags, NULL, NULL) == SOCKET_ERROR)
{
if (WSAGetLastError() != WSAEWOULDBLOCK)
{
printf("WSARecv() failed with error %d\n", WSAGetLastError());
FreeSocketInformation(wParam);
return 0;
}
}
else // No error so update the byte count
{
SocketInfo->BytesRECV = RecvBytes;
}
}

// DO NOT BREAK HERE SINCE WE GOT A SUCCESSFUL RECV. Go ahead
// and begin writing data to the client.

case FD_WRITE:

SocketInfo = GetSocketInformation(wParam);

if (SocketInfo->BytesRECV > SocketInfo->BytesSEND)
{
SocketInfo->DataBuf.buf = SocketInfo->Buffer + SocketInfo->BytesSEND;
SocketInfo->DataBuf.len = SocketInfo->BytesRECV - SocketInfo->BytesSEND;

if (WSASend(SocketInfo->Socket, &(SocketInfo->DataBuf), 1, &SendBytes, 0,
NULL, NULL) == SOCKET_ERROR)
{
if (WSAGetLastError() != WSAEWOULDBLOCK)
{
printf("WSASend() failed with error %d\n", WSAGetLastError());
FreeSocketInformation(wParam);
return 0;
}
}

[hejie19q2004]

else // No error so update the byte count
{
SocketInfo->BytesSEND += SendBytes;
}
}

if (SocketInfo->BytesSEND == SocketInfo->BytesRECV)
{
SocketInfo->BytesSEND = 0;
SocketInfo->BytesRECV = 0;

// If a RECV occurred during our SENDs then we need to post an FD_READ
// notification on the socket.

if (SocketInfo->RecvPosted == TRUE)
{
SocketInfo->RecvPosted = FALSE;
PostMessage(hwnd, WM_SOCKET, wParam, FD_READ);
}
}

break;

case FD_CLOSE:

printf("Closing socket %d\n", wParam);
FreeSocketInformation(wParam);

break;
}
}
return 0;
}

return DefWindowProc(hwnd, uMsg, wParam, lParam);
}


void CreateSocketInformation(SOCKET s)
{
LPSOCKET_INFORMATION SI;

if ((SI = (LPSOCKET_INFORMATION) GlobalAlloc(GPTR,
sizeof(SOCKET_INFORMATION))) == NULL)
{
printf("GlobalAlloc() failed with error %d\n", GetLastError());
return;
}

// Prepare SocketInfo structure for use.

SI->Socket = s;
SI->RecvPosted = FALSE;
SI->BytesSEND = 0;
SI->BytesRECV = 0;

SI->Next = SocketInfoList;

SocketInfoList = SI;
}

LPSOCKET_INFORMATION GetSocketInformation(SOCKET s)
{
SOCKET_INFORMATION *SI = SocketInfoList;

while(SI)
{
if (SI->Socket == s)
return SI;

SI = SI->Next;
}

return NULL;
}

void FreeSocketInformation(SOCKET s)
{
SOCKET_INFORMATION *SI = SocketInfoList;
SOCKET_INFORMATION *PrevSI = NULL;

while(SI)
{
if (SI->Socket == s)
{
if (PrevSI)
PrevSI->Next = SI->Next;
else
SocketInfoList = SI->Next;

closesocket(SI->Socket);
GlobalFree(SI);
return;
}

PrevSI = SI;
SI = SI->Next;
}
}

HWND MakeWorkerWindow(void)
{
WNDCLASS wndclass;
CHAR *ProviderClass = "AsyncSelect";
HWND Window;

wndclass.style = CS_HREDRAW | CS_VREDRAW;
wndclass.lpfnWndProc = (WNDPROC)WindowProc;
wndclass.cbClsExtra = 0;
wndclass.cbWndExtra = 0;
wndclass.hInstance = NULL;
wndclass.hIcon = LoadIcon(NULL, IDI_APPLICATION);
wndclass.hCursor = LoadCursor(NULL, IDC_ARROW);
wndclass.hbrBackground = (HBRUSH) GetStockObject(WHITE_BRUSH);
wndclass.lpszMenuName = NULL;
wndclass.lpszClassName = ProviderClass;

if (RegisterClass(&wndclass) == 0)
{
printf("RegisterClass() failed with error %d\n", GetLastError());
return NULL;
}

// Create a window.

if ((Window = CreateWindow(
ProviderClass,
"",
WS_OVERLAPPEDWINDOW,
CW_USEDEFAULT,
CW_USEDEFAULT,
CW_USEDEFAULT,
CW_USEDEFAULT,
NULL,
NULL,
NULL,
NULL)) == NULL)
{
printf("CreateWindow() failed with error %d\n", GetLastError());
return NULL;
}

return Window;
}

[xiangding]

代码不错，但是太长

[xxbtop]

实际上一个server.cpp和一个client.cpp就可以实现简单的socket通信

[ghost8367]

套接字设置成非阻塞的，用select轮寻的接受．

[freemme]

如果要实现效率比较高的服务器，用完成端口是最好的，由操作系统帮你管理数据的io工作。

[kugou123]

用Select I/O ，一个线程默认可以管理64个连接。

[winnuke]

选择一下io模型..