[程式]目錄監控原始碼

最近更新了顯示程式方式，也好久沒有更新了。

這是我在KWallPaper 中使用的目錄監控Class。

由於在寫這程式時，曾參考上網路上的許多範例，因此在此分享與回饋~

在取得檔案變動時，我是將其變動放入一個queue中，如果直接寫入資料庫，延遲的時間，會造成後面的檔案沒有監控到。

此程式碼還有許多不足之處，歡迎批評指教，謝謝

#include "StdAfx.h"
#include ".\directorymonitor.h"
#include "ImgManager.h"

unsigned __stdcall DirectoryMonitorThreadCallback(LPVOID lpParm)
{
 CDirectoryMonitor* pObj = (CDirectoryMonitor*) lpParm;

 if( !pObj )
 {
  _endthreadex( 0 );
  return 0;
 }

 pObj->RunThread();
 _endthreadex( 0 );
 return 0;
}

CDirectoryMonitor::CDirectoryMonitor( CImgManager* pOwnter ):
m_pOwner(pOwnter),
m_hCompletionPort(NULL),
m_ulCompletionKey(0),
m_hDir(NULL),
m_pBuffer(NULL),
m_nBufferSize(0)
{
 memset( &m_Overlapped, 0, sizeof(m_Overlapped) );

}
CDirectoryMonitor::~CDirectoryMonitor(void)
{
 if( m_hCompletionPort )
 {
  //The thread will catch this and exit the thread
  PostQueuedCompletionStatus(m_hCompletionPort, 0, 0, NULL); 
  Sleep(1000);

  for( unsigned int i = 0; i < m_nThreadCount; ++i )
  {
   HANDLE nThread = m_vecThread[i];

   //wait for it to exit
   WaitForSingleObject(nThread, INFINITE);
   SAFE_CLOSEHANDLE(nThread);
  }
  m_hCompletionPort = NULL;
  m_vecThread.clear();
 }
 SAFE_CLOSEHANDLE(m_hDir);

 SAFE_DELETE_ARRAY(m_pBuffer);
 m_nBufferSize = 0;
}

bool CDirectoryMonitor::Initialize( const TCHAR* szPath )
{
 m_strMoniDir = szPath;

 m_hDir = CreateFile( m_strMoniDir.c_str(),        // pointer to the file name
       FILE_LIST_DIRECTORY,        // access (read/write) mode
       FILE_SHARE_READ|FILE_SHARE_DELETE|FILE_SHARE_WRITE, // share mode
       NULL,            // security descriptor
       OPEN_EXISTING,          // how to create
       FILE_FLAG_BACKUP_SEMANTICS|FILE_FLAG_OVERLAPPED, // file attributes
       NULL            // file with attributes to copy
       );

 if ( INVALID_HANDLE_VALUE == m_hDir )
  return false;

 SYSTEM_INFO SystemInfo;
 GetSystemInfo(&SystemInfo);

 m_nThreadCount = 1; //SystemInfo.dwNumberOfProcessors;

 m_hCompletionPort = CreateIoCompletionPort(
            m_hDir,                        // Handle to a file opened for overlapped I/O completion.
            NULL,                          // existed Handle to the I/O completion port. 
            (ULONG_PTR)&m_ulCompletionKey, // CompletionKey
            m_nThreadCount             // NumberOfConcurrentThreads
            );

 if( NULL == m_hCompletionPort )
  return false;

 m_nBufferSize = 4096;//2*(sizeof(FILE_NOTIFY_INFORMATION)+MAX_PATH);
 m_pBuffer = new char[m_nBufferSize];

 if( !_callReadDirectoryChanges() )
  return false;

 for( unsigned int i = 0; i < m_nThreadCount; ++i)
 {
  HANDLE nThread = (HANDLE)_beginthreadex( NULL, 0, &::DirectoryMonitorThreadCallback, (LPVOID)this, 0, NULL );

  if( NULL != nThread )
  {
   m_vecThread.push_back( nThread );
  }
 } 

 KLOG( LOG_DEBUG, _T("DirectoryMonitor : %s"), m_strMoniDir.c_str() );

 return true;
}

void CDirectoryMonitor::RunThread()
{
 BOOL bSucceed = FALSE;
 DWORD dwBytesReturned = 0;
 TCHAR szFileName[MAX_PATH] = {0};
 TCHAR szNotiryFileName[MAX_PATH] = {0};
 DWORD dwAction = 0;

 while(TRUE)
 { 
  ::Sleep(1);
  LPOVERLAPPED lpOverlapped = &m_Overlapped;
  bSucceed = GetQueuedCompletionStatus( m_hCompletionPort,             // [in]Handle to the completion port of interest.
            &dwBytesReturned,     // lpNumberOfBytes
            &m_ulCompletionKey,            // lpCompletionKey 
            &lpOverlapped,                 // lpOverlapped 
            INFINITE                       // dwMilliseconds 
            );

  if( NULL == lpOverlapped )
   break;

  if(!bSucceed || 0 == m_ulCompletionKey )
   continue;

  FILE_NOTIFY_INFORMATION * pNotify = (FILE_NOTIFY_INFORMATION*)m_pBuffer;
  DWORD dwNextEntryOffset = 0;

  do
  {
   pNotify = (FILE_NOTIFY_INFORMATION*)&m_pBuffer[dwNextEntryOffset];

   dwNextEntryOffset += pNotify->NextEntryOffset;
   dwAction   = pNotify->Action;

   memset( szNotiryFileName, 0, sizeof(szNotiryFileName));
   _tcsncpy( szNotiryFileName, pNotify->FileName, pNotify->FileNameLength);
   szNotiryFileName[pNotify->FileNameLength / sizeof(TCHAR) ] = '\0';
   _stprintf( szFileName, _T("%s\\%s"), m_strMoniDir.c_str(), szNotiryFileName );

   if( m_pOwner )
    m_pOwner->NotifyFileChange( dwAction, szFileName );

  }while ( 0 != pNotify->NextEntryOffset );

  _callReadDirectoryChanges();
 }
}

bool CDirectoryMonitor::Release()
{
 return true;
}

bool CDirectoryMonitor::_callReadDirectoryChanges()
{
 if( m_pBuffer )
 {
  memset( m_pBuffer, 0, m_nBufferSize );
 }

 BOOL BRet = ReadDirectoryChangesW(  m_hDir,    // hDirectory. Handle to the directory to be monitored
       m_pBuffer,      // [in, out] Pointer to the formatted buffer in which the read results are to be returned. 
       m_nBufferSize,     // [in] Length of the buffer pointed to by the lpBuffer parameter, in bytes. 
       true,       // bWatchSubtree 
        FILE_NOTIFY_CHANGE_FILE_NAME| // [in] Filter criteria the function checks to determine if the wait operation has completed.
        FILE_NOTIFY_CHANGE_DIR_NAME|
        FILE_NOTIFY_CHANGE_CREATION,
       NULL,       // lpBytesReturned. For asynchronous calls, this parameter is undefined.
       &m_Overlapped,     // [in] Pointer to an OVERLAPPED structure that supplies data to be used during asynchronous operation.
       NULL );       // lpCompletionRoutine

 return BRet == TRUE ? true : false;
}

以上，歡迎參考~

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