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Diffstat (limited to 'IvyFileMon/DelayedDirectoryChangeHandler.h')
| -rw-r--r-- | IvyFileMon/DelayedDirectoryChangeHandler.h | 336 |
1 files changed, 336 insertions, 0 deletions
diff --git a/IvyFileMon/DelayedDirectoryChangeHandler.h b/IvyFileMon/DelayedDirectoryChangeHandler.h new file mode 100644 index 0000000..5409c5b --- /dev/null +++ b/IvyFileMon/DelayedDirectoryChangeHandler.h @@ -0,0 +1,336 @@ +// DelayedDirectoryChangeHandler.h: interface for the CDelayedDirectoryChangeHandler2 class.
+//
+//////////////////////////////////////////////////////////////////////
+//
+// You needn't worry about the classes in this file.
+// they are implementation classes used to help CDirectoryChangeWatcher work.
+//
+//
+
+#if !defined(AFX_DELAYEDDIRECTORYCHANGEHANDLER_H__F20EC22B_1C79_403E_B43C_938F95723D45__INCLUDED_)
+#define AFX_DELAYEDDIRECTORYCHANGEHANDLER_H__F20EC22B_1C79_403E_B43C_938F95723D45__INCLUDED_
+
+#if _MSC_VER > 1000
+#pragma once
+#endif // _MSC_VER > 1000
+
+//classes declrared in other files:
+class CDirectoryChangeWatcher;
+class CDirectoryChangeHandler;
+//classes declared in this file:
+class CDirChangeNotification;
+class CDelayedDirectoryChangeHandler;
+
+class CDelayedNotificationWindow;
+class CDelayedNotificationThread;
+
+/*******************************************************************
+ The classes in this file implement methods to ensure that file change
+ notifications are fired in a thread other than the worker thread used
+ by CDirectoryChangeWatcher.
+
+ Dispatching the notifications in to a different thread improves the performance
+ of CDirectoryChangeWatcher so that it can process more notifications faster
+ and notifications aren't 'lost'.
+
+
+ There are two methods of dispatching functions to another thread.
+
+ 1) One is to use the message pump associated w/ the main thread by posting notifications
+ to a hidden window. This is implemented w/ the class CDelayedNotificationWindow.
+
+ 2) The other is to create a worker thread that implements a message pump. This is
+ implemented w/ the class CDelayedNotificationThread.
+
+
+ If your app uses a GUI then it has a already has message pump.
+ You can make sure that CDelayedNotificationWindow is used in this case.
+ The advantage here being that there is one less worker thread used in your program.
+
+ If your app is a command line app or otherwise doesn't have a GUI,
+ then you will want to make sure that you are using the CDelayedNotificationThread
+ to dispatch notifications to another thread.
+
+ This is determined by a flag passed is passed to the constructor of CDirecotryChangeWatcher
+
+********************************************************************/
+
+class CDelayedNotifier
+//
+// Abstract base class for ensuring notifications are fired in a thread
+//
+//
+{
+public:
+ virtual ~CDelayedNotifier(){}
+ virtual void PostNotification(CDirChangeNotification * pNotification) = 0;
+
+};
+
+class CDelayedNotificationWindow : public CDelayedNotifier
+//
+// A class that implements a
+// there will always be only one of the actual windows
+// in existance.
+//
+{
+public:
+ CDelayedNotificationWindow(){ AddRef(); }
+ virtual ~CDelayedNotificationWindow(){ Release(); }
+
+
+ void PostNotification(CDirChangeNotification * pNotification);
+private:
+ long AddRef(); // the window handle is reference counted
+ long Release(); //
+
+ static long s_nRefCnt;
+ static HWND s_hWnd; //there's only one window no matter how many instances of this class there are.... this means that all notifications are handled by the same thread.
+ static BOOL s_bRegisterWindow;
+ BOOL RegisterWindowClass(LPCTSTR szClassName);
+ BOOL CreateNotificationWindow();
+};
+
+class CDelayedNotificationThread : public CDelayedNotifier
+//
+// Class that implements a worker thread w/ a message pump.
+// CDirectoryChangeWatcher posts notifications to this thread, where they are dispatched.
+// This thread executes CDirectoryChangeHandler notifications.
+//
+{
+public:
+ CDelayedNotificationThread()
+ :m_hThreadStartEvent(NULL)
+ {
+ m_hThreadStartEvent = CreateEvent(NULL,FALSE,FALSE,NULL);
+ ASSERT( m_hThreadStartEvent );
+ AddRef();
+ }
+ virtual ~CDelayedNotificationThread()
+ {
+ Release();
+ if( m_hThreadStartEvent )
+ CloseHandle(m_hThreadStartEvent), m_hThreadStartEvent = NULL;
+ }
+
+ void PostNotification(CDirChangeNotification * pNotification);
+
+private:
+ long AddRef(); // The thread handle is reference
+ long Release(); // counted so that only one thread is used
+ // so that there's only one worker thread(performing this functino)
+ static long s_nRefCnt; // no matter how many directories are being watched
+ static HANDLE s_hThread; //
+ static DWORD s_dwThreadID; //
+
+ static UINT __stdcall ThreadFunc(LPVOID lpvThis);
+
+ bool StartThread();
+ bool StopThread();
+
+ BOOL WaitForThreadStartup(){ return WaitForSingleObject(m_hThreadStartEvent, INFINITE) == WAIT_OBJECT_0; };
+ BOOL SignalThreadStartup(){ return SetEvent( m_hThreadStartEvent ) ; }
+
+ HANDLE m_hThreadStartEvent;//signals that the worker thread has started. this fixes a bug condition.
+
+};
+
+
+class CDirChangeNotification
+//
+// A class to help dispatch the change notifications to the main thread.
+//
+// This class holds the data in memory until the notification can be dispatched.(ie: this is the time between when the notification is posted, and the clients notification code is called).
+//
+//
+{
+private:
+ CDirChangeNotification();//not implemented
+public:
+ explicit CDirChangeNotification(CDelayedDirectoryChangeHandler * pDelayedHandler, DWORD dwPartialPathOffset);
+ ~CDirChangeNotification();
+
+ //
+ //
+ void PostOn_FileAdded(LPCTSTR szFileName);
+ void PostOn_FileRemoved(LPCTSTR szFileName);
+ void PostOn_FileNameChanged(LPCTSTR szOldName, LPCTSTR szNewName);
+ void PostOn_FileModified(LPCTSTR szFileName);
+ void PostOn_ReadDirectoryChangesError(DWORD dwError, LPCTSTR szDirectoryName);
+ void PostOn_WatchStarted(DWORD dwError, LPCTSTR szDirectoryName);
+ void PostOn_WatchStopped(LPCTSTR szDirectoryName);
+
+ void DispatchNotificationFunction();
+
+
+ enum eFunctionToDispatch{ eFunctionNotDefined = -1,
+ eOn_FileAdded = FILE_ACTION_ADDED,
+ eOn_FileRemoved = FILE_ACTION_REMOVED,
+ eOn_FileModified = FILE_ACTION_MODIFIED,
+ eOn_FileNameChanged = FILE_ACTION_RENAMED_OLD_NAME,
+ eOn_ReadDirectoryChangesError,
+ eOn_WatchStarted,
+ eOn_WatchStopped
+ };
+protected:
+ void PostNotification();
+
+private:
+ friend class CDelayedDirectoryChangeHandler;
+ CDelayedDirectoryChangeHandler * m_pDelayedHandler;
+
+ //
+ // Members to help implement DispatchNotificationFunction
+ //
+ //
+
+ eFunctionToDispatch m_eFunctionToDispatch;
+ //Notification Data:
+ TCHAR * m_szFileName1;//<-- is the szFileName parameter to On_FileAdded(),On_FileRemoved,On_FileModified(), and is szOldFileName to On_FileNameChanged(). Is also strDirectoryName to On_ReadDirectoryChangesError(), On_WatchStarted(), and On_WatchStopped()
+ TCHAR * m_szFileName2;//<-- is the szNewFileName parameter to On_FileNameChanged()
+ DWORD m_dwError; //<-- is the dwError parameter to On_WatchStarted(), and On_ReadDirectoryChangesError()
+ //
+
+ DWORD m_dwPartialPathOffset;//helps support FILTERS_CHECK_PARTIAL_PATH...not passed to any functions other than may be used during tests in CDelayedDirectoryChangeHandler::NotifyClientOfFileChange()
+
+
+ friend class CDirChangeNotification;
+ friend class CDirectoryChangeWatcher;
+ friend DWORD GetPathOffsetBasedOnFilterFlags(CDirChangeNotification*,DWORD);//a friend function
+};
+
+
+//////////////////////////////////////////////////////////////////////////
+//
+// This class makes it so that a file change notification is executed in the
+// context of the main thread, and not the worker thread.
+//
+//
+// It works by creating a hidden window. When it receieves a notification
+// via one of the On_Filexxx() functions, a message is posted to this window.
+// when the message is handled, the notification is fired again in the context
+// of the main thread, or whichever thread that called CDirectoryChangeWatcher::WatchDirectory()
+//
+//
+/////////////////////////////////////////////////////////////////////////////
+// Note this code wants to use PathMatchSpec()
+// which is only supported on WINNT 4.0 w/ Internet Explorer 4.0 and above.
+// PathMatchSpec is fully supported on Win2000/XP.
+//
+// For the case of WINNT 4.0 w/out IE 4.0, we'll use a simpler function.
+// some functionality is lost, but such is the price.
+//
+
+typedef BOOL (STDAPICALLTYPE * FUNC_PatternMatchSpec)(LPCTSTR pszFile, LPCTSTR pszSpec);
+
+class CDelayedDirectoryChangeHandler : public CDirectoryChangeHandler
+//
+// Decorates an instance of a CDirectoryChangeHandler object.
+// Intercepts notification function calls and posts them to
+// another thread through a method implemented by a class derived from
+// CDelayedNotifier
+//
+//
+// This class implements dispatching the notifications to a thread
+// other than CDirectoryChangeWatcher::MonitorDirectoryChanges()
+//
+// Also supports the include and exclude filters for each directory
+//
+{
+private:
+ CDelayedDirectoryChangeHandler();//not implemented.
+public:
+ CDelayedDirectoryChangeHandler( CDirectoryChangeHandler * pRealHandler, bool bAppHasGUI, LPCTSTR szIncludeFilter, LPCTSTR szExcludeFilter, DWORD dwFilterFlags);
+ virtual ~CDelayedDirectoryChangeHandler();
+
+
+ CDirectoryChangeHandler * GetRealChangeHandler()const { return m_pRealHandler; }
+ CDirectoryChangeHandler * & GetRealChangeHandler(){ return m_pRealHandler; }//FYI: PCLint will give a warning that this exposes a private/protected member& defeats encapsulation.
+
+ void PostNotification(CDirChangeNotification * pNotification);
+ void DispatchNotificationFunction(CDirChangeNotification * pNotification);
+
+
+protected:
+ //These functions are called when the directory to watch has had a change made to it
+ void On_FileAdded(const CString & strFileName);
+ void On_FileRemoved(const CString & strFileName);
+ void On_FileModified(const CString & strFileName);
+ void On_FileNameChanged(const CString & strOldFileName, const CString & strNewFileName);
+ void On_ReadDirectoryChangesError(DWORD dwError, const CString & strDirectoryName);
+
+ void On_WatchStarted(DWORD dwError, const CString & strDirectoryName);
+ void On_WatchStopped(const CString & strDirectoryName);
+
+
+ void SetChangedDirectoryName(const CString & strChangedDirName);
+ const CString & GetChangedDirectoryName()const;
+
+ BOOL WaitForOnWatchStoppedDispatched();//see comments in .cpp
+
+
+ bool NotifyClientOfFileChange(CDirChangeNotification * pNot);
+
+ bool IncludeThisNotification(LPCTSTR szFileName); // based on file name.
+ bool ExcludeThisNotification(LPCTSTR szFileName); // Allows us to filter notifications
+ //
+
+
+
+ CDirChangeNotification * GetNotificationObject();
+ void DisposeOfNotification(CDirChangeNotification * pNotification);
+
+ CDelayedNotifier * m_pDelayNotifier;
+ CDirectoryChangeHandler * m_pRealHandler;
+
+ // m_bAppHasGUI:
+ // This flag, if set to true, indicates that the app has a message
+ bool m_bAppHasGUI; // pump, and that functions are dispatched to the main thread.
+ // Otherwise, functions are dispatched to a separate worker thread.
+ //
+ DWORD m_dwFilterFlags;
+
+ DWORD m_dwPartialPathOffset; //helps support FILTERS_CHECK_PARTIAL_PATH
+ void SetPartialPathOffset(const CString & strWatchedDirName);
+
+ friend class CDirectoryChangeWatcher;
+ friend class CDirectoryChangeWatcher::CDirWatchInfo;
+
+private:
+ HANDLE m_hWatchStoppedDispatchedEvent;//supports WaitForOnWatchStoppedDispatched()
+
+ TCHAR * m_szIncludeFilter; // Supports the include
+ TCHAR * m_szExcludeFilter; // & exclude filters
+
+ //
+ // Load PathMatchSpec dynamically because it's only supported if IE 4.0 or greater is
+ // installed.
+ static HMODULE s_hShlwapi_dll;//for the PathMatchSpec() function
+ static BOOL s_bShlwapi_dllExists;//if on NT4.0 w/out IE 4.0 or greater, this'll be false
+ static long s_nRefCnt_hShlwapi;
+ static FUNC_PatternMatchSpec s_fpPatternMatchSpec;
+
+ BOOL _PathMatchSpec(LPCTSTR szPath, LPCTSTR szPattern);
+ BOOL InitializePathMatchFunc(LPCTSTR szIncludeFilter, LPCTSTR szExcludeFilter);
+ BOOL InitializePatterns(LPCTSTR szIncludeFilter, LPCTSTR szExcludeFilter);
+ void UninitializePathMatchFunc();
+
+ bool UsesRealPathMatchSpec() const;//are we using PathMatchSpec() or wildcmp()?
+
+ //note: if the PathMatchSpec function isn't found, wildcmp() is used instead.
+ //
+ // to support multiple file specs separated by a semi-colon,
+ // the include and exclude filters that are passed into the
+ // the constructor are parsed into separate strings
+ // which are all checked in a loop.
+ //
+ int m_nNumIncludeFilterSpecs;
+ int m_nNumExcludeFilterSpecs;
+
+
+};
+
+
+
+
+#endif // !defined(AFX_DELAYEDDIRECTORYCHANGEHANDLER_H__F20EC22B_1C79_403E_B43C_938F95723D45__INCLUDED_)
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