JetByteTools（一）

ICOP可以这么简单？

class  CIOCompletionPort
{
public :
     explicit  CIOCompletionPort(size_t maxConcurrency);
     ~ CIOCompletionPort();

     void  AssociateDevice(HANDLE hDevice, ULONG_PTR completionKey);

     void  PostStatus(ULONG_PTR completionKey, DWORD dwNumBytes  =   0 , OVERLAPPED  * pOverlapped  =   0 );

     void  GetStatus(ULONG_PTR  * pCompletionKey, PDWORD pdwNumBytes, OVERLAPPED  ** ppOverlapped);

     bool  GetStatus(ULONG_PTR  * pCompletionKey, PDWORD pdwNumBytes, OVERLAPPED  ** ppOverlapped, DWORD dwMilliseconds);

private :
 HANDLE m_iocp;

     //  No copies do not implement
    CIOCompletionPort( const  CIOCompletionPort  & rhs);
    CIOCompletionPort  & operator = ( const  CIOCompletionPort  & rhs);
} ;

 

CIOCompletionPort::CIOCompletionPort(
   size_t maxConcurrency)
   :  m_iocp(::CreateIoCompletionPort(INVALID_HANDLE_VALUE, NULL,  0 , maxConcurrency))
{
    if  (m_iocp  ==   0 )
    {
       throw  CWin32Exception(_T( " CIOCompletionPort::CIOCompletionPort() - CreateIoCompletionPort " ), ::GetLastError());
   }
}

CIOCompletionPort:: ~ CIOCompletionPort() 
{ 
   ::CloseHandle(m_iocp);
}

void  CIOCompletionPort::AssociateDevice(
   HANDLE hDevice, 
   ULONG_PTR completionKey) 
{
    if  (m_iocp  !=  ::CreateIoCompletionPort(hDevice, m_iocp, completionKey,  0 ))
    {
       throw  CWin32Exception(_T( " CIOCompletionPort::AssociateDevice() - CreateIoCompletionPort " ), ::GetLastError());
   }
}

void  CIOCompletionPort::PostStatus(
   ULONG_PTR completionKey, 
   DWORD dwNumBytes  /**/ /*  = 0  */ , 
   OVERLAPPED  * pOverlapped  /**/ /*  = 0  */ ) 
{
    if  ( 0   ==  ::PostQueuedCompletionStatus(m_iocp, dwNumBytes, completionKey, pOverlapped))
    {
       throw  CWin32Exception(_T( " CIOCompletionPort::PostStatus() - PostQueuedCompletionStatus " ), ::GetLastError());
   }
}

void  CIOCompletionPort::GetStatus(
   ULONG_PTR  * pCompletionKey, 
   PDWORD pdwNumBytes,
   OVERLAPPED  ** ppOverlapped)
{
    if  ( 0   ==  ::GetQueuedCompletionStatus(m_iocp, pdwNumBytes, pCompletionKey, ppOverlapped, INFINITE))
    {
       throw  CWin32Exception(_T( " CIOCompletionPort::GetStatus() - GetQueuedCompletionStatus " ), ::GetLastError());
   }
}

bool  CIOCompletionPort::GetStatus(
   ULONG_PTR  * pCompletionKey, 
   PDWORD pdwNumBytes,
   OVERLAPPED  ** ppOverlapped, 
   DWORD dwMilliseconds)
{
    bool  ok  =   true ;

    if  ( 0   ==  ::GetQueuedCompletionStatus(m_iocp, pdwNumBytes, pCompletionKey, ppOverlapped, dwMilliseconds))
    {
      DWORD lastError  =  ::GetLastError();

       if  (lastError  !=  WAIT_TIMEOUT)
       {
          throw  CWin32Exception(_T( " CIOCompletionPort::GetStatus() - GetQueuedCompletionStatus " ), lastError);
      }

      ok  =   false ;
   }

    return  ok;
}

SURE，IOCP 在WINDOWS下是一种机制，一种高效的IO访问机制，‘IO’不仅仅只限于网络，这样就变得简单多了!