iocp进行SOCKET通信

当然TCP方式的模型还有事件选择模型。
就是把所有的网络事件和我们的一个程序里定义的事件梆定。
这个有它的好处,可能可以让我们更好的写一个线程来管理
接收与发送。
现在来讲一下一个完成端口模型。

  完成端口
 
一个完成端口其实就是一个通知队列,由操作系统把已经完成的重叠I/O请求的通知
放入其中。当某项I/O操作一旦完成,某个可以对该操作结果进行处理的工作者线程
就会收到一则通知。而套接字在被创建后,可以在任何时候与某个完成端口进行关
联。
 
步骤:
1、创建一个空的完成端口;
2、得到本地机器的CPU个数;
3、开启CPU*2个工作线程(又名线程池),全部都在等待完成端口的完成包;
4、创建TCP的监听socket,使用事件邦定,创建监听线程;
5、当有人连接进入的时候,将Client socket保存到一个我们自己定义的关键键,
    并把它与我们创建的完成端口关联;
6、使用WSARecv和WSASend函数投递一些请求,这是使用重叠I/O的方式;
7、重复5~6;

注:1、重叠I/O的方式中,接收与发送数据包的时候,一定要进行投递请求这是
   它们这个体系结构的特点
   当然,在完成端口方式中,不是直接使用的WSARecv和WSASend函数进行请求
   的投递的。而是使用的ReadFile,Write的方式
  2、完成端口使用了系统内部的一些模型,所以我们只要按照一定的顺序调用就
   可以完成了。
  3、完成端口是使用在这样的情况下,有成千上万的用户连接的时候,它能够
   保证性能不会降低。


 

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

#define PORT 5150
#define DATA_BUFSIZE 8192

// 关键项
typedef struct
{
   OVERLAPPED Overlapped;
   WSABUF DataBuf;
   CHAR Buffer[DATA_BUFSIZE];
   DWORD BytesSEND;
   DWORD BytesRECV;
}
PER_IO_OPERATION_DATA, * LPPER_IO_OPERATION_DATA;


typedef
struct  
{
   SOCKET Socket;
}
PER_HANDLE_DATA, * LPPER_HANDLE_DATA;

DWORD WINAPI ServerWorkerThread(LPVOID CompletionPortID);

void main( void )
{
   SOCKADDR_IN InternetAddr;
   SOCKET Listen;
   SOCKET Accept;
   HANDLE CompletionPort;
   SYSTEM_INFO SystemInfo;
   LPPER_HANDLE_DATA PerHandleData;
   LPPER_IO_OPERATION_DATA PerIoData;
  
int i;
   DWORD RecvBytes;
   DWORD Flags;
   DWORD ThreadID;
   WSADATA wsaData;
   DWORD Ret;

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


  
// 打开一个空的完成端口

  
if ((CompletionPort = CreateIoCompletionPort(INVALID_HANDLE_VALUE, NULL, 0 , 0 )) == NULL)
  
{
      printf(
" CreateIoCompletionPort failed with error: %d\n " , GetLastError());
     
return ;
   }


  
// Determine how many processors are on the system.

   GetSystemInfo(
& SystemInfo);

  
// 开启cpu个数的2倍个的线程

  
for (i =   0 ; i < SystemInfo.dwNumberOfProcessors *   2 ; i ++ )
  
{
      HANDLE ThreadHandle;

     
// Create a server worker thread and pass the completion port to the thread.

     
if ((ThreadHandle = CreateThread(NULL, 0 , ServerWorkerThread, CompletionPort,
        
0 , & ThreadID)) == NULL)
     
{
         printf(
" CreateThread() failed with error %d\n " , GetLastError());
        
return ;
      }


     
// Close the thread handle
      CloseHandle(ThreadHandle);
   }


  
// 打开一个服务器socket

  
if ((Listen = WSASocket(AF_INET, SOCK_STREAM, 0 , NULL, 0 ,
      WSA_FLAG_OVERLAPPED))
== INVALID_SOCKET)
  
{
      printf(
" WSASocket() failed with error %d\n " , WSAGetLastError());
     
return ;
   }
 

   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 ) == SOCKET_ERROR)
  
{
      printf(
" listen() failed with error %d\n " , WSAGetLastError());
     
return ;
   }


  
// 开始接收从客户端来的连接

  
while (TRUE)
  
{
     
if ((Accept = WSAAccept(Listen, NULL, NULL, NULL, 0 )) == SOCKET_ERROR)
     
{
         printf(
" WSAAccept() failed with error %d\n " , WSAGetLastError());
        
return ;
      }


     
// 创建一个关键项用于保存这个客户端的信息,用户接收发送的重叠结构,
     
// 还有使用到的缓冲区
      if ((PerHandleData = (LPPER_HANDLE_DATA) GlobalAlloc(GPTR,
        
sizeof (PER_HANDLE_DATA))) == NULL)
     
{
         printf(
" GlobalAlloc() failed with error %d\n " , GetLastError());
        
return ;
      }


     
// Associate the accepted socket with the original completion port.

      printf(
" Socket number %d connected\n " , Accept);
      PerHandleData
-> Socket = Accept;

     
// 与我们的创建的那个完成端口关联起来,将关键项也与指定的一个完成端口关联
      if (CreateIoCompletionPort((HANDLE) Accept, CompletionPort, (DWORD) PerHandleData,
        
0 ) == NULL)
     
{
         printf(
" CreateIoCompletionPort failed with error %d\n " , GetLastError());
        
return ;
      }


     
// 投递一次接收,由于接收都需要使用这个函数来投递一个接收的准备

     
if ((PerIoData = (LPPER_IO_OPERATION_DATA) GlobalAlloc(GPTR,          sizeof (PER_IO_OPERATION_DATA))) == NULL)
     
{
         printf(
" GlobalAlloc() failed with error %d\n " , GetLastError());
        
return ;
      }


      ZeroMemory(
& (PerIoData -> Overlapped), sizeof (OVERLAPPED));
      PerIoData
-> BytesSEND =   0 ;
      PerIoData
-> BytesRECV =   0 ;
      PerIoData
-> DataBuf.len = DATA_BUFSIZE;
      PerIoData
-> DataBuf.buf = PerIoData -> Buffer;

      Flags
=   0 ;
     
if (WSARecv(Accept, & (PerIoData -> DataBuf), 1 , & RecvBytes, & Flags,
        
& (PerIoData -> Overlapped), NULL) == SOCKET_ERROR)
     
{
        
if (WSAGetLastError() != ERROR_IO_PENDING)
        
{
            printf(
" WSARecv() failed with error %d\n " , WSAGetLastError());
           
return ;
         }

      }

   }

}

// 工作线程
DWORD WINAPI ServerWorkerThread(LPVOID CompletionPortID)
{
   HANDLE CompletionPort
= (HANDLE) CompletionPortID;
   DWORD BytesTransferred;
   LPOVERLAPPED Overlapped;
   LPPER_HANDLE_DATA PerHandleData;
   LPPER_IO_OPERATION_DATA PerIoData;
   DWORD SendBytes, RecvBytes;
   DWORD Flags;
  
  
while (TRUE)
  
{
     
// 完成端口有消息来了
      if (GetQueuedCompletionStatus(CompletionPort, & BytesTransferred,
         (LPDWORD)
& PerHandleData, (LPOVERLAPPED * ) & PerIoData, INFINITE) ==   0 )
     
{
         printf(
" GetQueuedCompletionStatus failed with error %d\n " , GetLastError());
        
return   0 ;
      }



     
// 是不是有人退出了

     
if (BytesTransferred ==   0 )
     
{
         printf(
" Closing socket %d\n " , PerHandleData -> Socket);

        
if (closesocket(PerHandleData -> Socket) == SOCKET_ERROR)
        
{
            printf(
" closesocket() failed with error %d\n " , WSAGetLastError());
           
return   0 ;
         }


         GlobalFree(PerHandleData);
         GlobalFree(PerIoData);
        
continue ;
      }


     
//

     
if (PerIoData -> BytesRECV ==   0 )
     
{
         PerIoData
-> BytesRECV = BytesTransferred;
         PerIoData
-> BytesSEND =   0 ;
      }

     
else
     
{
         PerIoData
-> BytesSEND += BytesTransferred;
      }


     
if (PerIoData -> BytesRECV > PerIoData -> BytesSEND)
     
{

        
// Post another WSASend() request.
        
// Since WSASend() is not gauranteed to send all of the bytes requested,
        
// continue posting WSASend() calls until all received bytes are sent.

         ZeroMemory(
& (PerIoData -> Overlapped), sizeof (OVERLAPPED));

         PerIoData
-> DataBuf.buf = PerIoData -> Buffer + PerIoData -> BytesSEND;
         PerIoData
-> DataBuf.len = PerIoData -> BytesRECV - PerIoData -> BytesSEND;

        
if (WSASend(PerHandleData -> Socket, & (PerIoData -> DataBuf), 1 , & SendBytes, 0 ,
           
& (PerIoData -> Overlapped), NULL) == SOCKET_ERROR)
        
{
           
if (WSAGetLastError() != ERROR_IO_PENDING)
           
{
               printf(
" WSASend() failed with error %d\n " , WSAGetLastError());
              
return   0 ;
            }

         }

      }

     
else
     
{
         PerIoData
-> BytesRECV =   0 ;

        
// Now that there are no more bytes to send post another WSARecv() request.

         Flags
=   0 ;
         ZeroMemory(
& (PerIoData -> Overlapped), sizeof (OVERLAPPED));

         PerIoData
-> DataBuf.len = DATA_BUFSIZE;
         PerIoData
-> DataBuf.buf = PerIoData -> Buffer;

        
if (WSARecv(PerHandleData -> Socket, & (PerIoData -> DataBuf), 1 , & RecvBytes, & Flags,
           
& (PerIoData -> Overlapped), NULL) == SOCKET_ERROR)
        
{
           
if (WSAGetLastError() != ERROR_IO_PENDING)
           
{
               printf(
" WSARecv() failed with error %d\n " , WSAGetLastError());
              
return   0 ;
            }

         }

      }

   }

}

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