protot/3rdparty/RuntimeCompiledCpp/RuntimeCompiler/SimpleFileWatcher/FileWatcherWin32.cpp

/**
	Copyright (c) 2009 James Wynn (james@jameswynn.com)

	Permission is hereby granted, free of charge, to any person obtaining a copy
	of this software and associated documentation files (the "Software"), to deal
	in the Software without restriction, including without limitation the rights
	to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
	copies of the Software, and to permit persons to whom the Software is
	furnished to do so, subject to the following conditions:

	The above copyright notice and this permission notice shall be included in
	all copies or substantial portions of the Software.

	THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
	IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
	FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
	AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
	LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
	OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
	THE SOFTWARE.
*/

#include "FileWatcherWin32.h"

#if FILEWATCHER_PLATFORM == FILEWATCHER_PLATFORM_WIN32

#include <windows.h>

#if defined(_MSC_VER)
#pragma comment(lib, "comctl32.lib")
#pragma comment(lib, "user32.lib")
#pragma comment(lib, "ole32.lib")

// disable secure warnings
#pragma warning (disable: 4996)
#endif

namespace FW
{
	/// Internal watch data
	struct WatchStruct
	{
		OVERLAPPED mOverlapped;
		HANDLE mDirHandle;
		BYTE mBuffer[32 * 1024];
		LPARAM lParam;
		DWORD mNotifyFilter;
		bool mStopNow;
		FileWatcherImpl* mFileWatcher;
		FileWatchListener* mFileWatchListener;
		char* mDirName;
		WatchID mWatchid;
		bool mIsRecursive;
	};

#pragma region Internal Functions

	// forward decl
	bool RefreshWatch(WatchStruct* pWatch, bool _clear = false);

	/// Unpacks events and passes them to a user defined callback.
	void CALLBACK WatchCallback(DWORD dwErrorCode, DWORD dwNumberOfBytesTransfered, LPOVERLAPPED lpOverlapped)
	{
#ifndef WIN32_FW_USE_FINDFIRST_API
		char szFile[MAX_PATH];
		PFILE_NOTIFY_INFORMATION pNotify;
		WatchStruct* pWatch = (WatchStruct*) lpOverlapped;
		size_t offset = 0;

		if(dwNumberOfBytesTransfered == 0)
			return;

		if (dwErrorCode == ERROR_SUCCESS)
		{
			do
			{
				pNotify = (PFILE_NOTIFY_INFORMATION) &pWatch->mBuffer[offset];
				offset += pNotify->NextEntryOffset;


				int count = WideCharToMultiByte(CP_ACP, 0, pNotify->FileName,
					pNotify->FileNameLength / sizeof(WCHAR),
					szFile, MAX_PATH - 1, NULL, NULL);
				szFile[count] = TEXT('\0');


				pWatch->mFileWatcher->handleAction(pWatch, szFile, pNotify->Action);

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

		if (!pWatch->mStopNow)
		{
			RefreshWatch(pWatch);
		}
#endif
	}

	/// Refreshes the directory monitoring.
	bool RefreshWatch(WatchStruct* pWatch, bool _clear)
	{
#ifndef WIN32_FW_USE_FINDFIRST_API
		return ReadDirectoryChangesW(
			pWatch->mDirHandle, pWatch->mBuffer, sizeof(pWatch->mBuffer), pWatch->mIsRecursive,
			pWatch->mNotifyFilter, NULL, &pWatch->mOverlapped, _clear ? 0 : WatchCallback) != 0;
#else
    return true;
#endif
	}

	/// Stops monitoring a directory.
	void DestroyWatch(WatchStruct* pWatch)
	{
		if (pWatch)
		{
			pWatch->mStopNow = TRUE;

#ifndef WIN32_FW_USE_FINDFIRST_API
			CancelIo(pWatch->mDirHandle);

			RefreshWatch(pWatch, true);

			if (!HasOverlappedIoCompleted(&pWatch->mOverlapped))
			{
				SleepEx(5, TRUE);
			}

			CloseHandle(pWatch->mOverlapped.hEvent);
			CloseHandle(pWatch->mDirHandle);
#endif

			delete[] pWatch->mDirName;
			HeapFree(GetProcessHeap(), 0, pWatch);
		}
	}

	/// Starts monitoring a directory.
	WatchStruct* CreateWatch(const char* szDirectory, bool recursive, DWORD mNotifyFilter)
	{
		WatchStruct* pWatch;
		size_t ptrsize = sizeof(*pWatch);
		pWatch = static_cast<WatchStruct*>(HeapAlloc(GetProcessHeap(), HEAP_ZERO_MEMORY, ptrsize));

#ifndef WIN32_FW_USE_FINDFIRST_API
		pWatch->mDirHandle = CreateFileA(szDirectory, FILE_LIST_DIRECTORY,
			FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, NULL, 
			OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS | FILE_FLAG_OVERLAPPED, NULL);

		if (pWatch->mDirHandle != INVALID_HANDLE_VALUE)
		{
			pWatch->mOverlapped.hEvent = CreateEvent(NULL, TRUE, FALSE, NULL);
			pWatch->mNotifyFilter = mNotifyFilter;
			pWatch->mIsRecursive = recursive;

			if (RefreshWatch(pWatch))
			{
				return pWatch;
			}
			else
			{
				CloseHandle(pWatch->mOverlapped.hEvent);
				CloseHandle(pWatch->mDirHandle);
			}
		}

		HeapFree(GetProcessHeap(), 0, pWatch);
		return NULL;
#else
        
    return pWatch;

#endif
	}

#pragma endregion

	//--------
	FileWatcherWin32::FileWatcherWin32()
		: mLastWatchID(0)
	{
	}

	//--------
	FileWatcherWin32::~FileWatcherWin32()
	{
		WatchMap::iterator iter = mWatches.begin();
		WatchMap::iterator end = mWatches.end();
		for(; iter != end; ++iter)
		{
			DestroyWatch(iter->second);
		}
		mWatches.clear();
	}

	//--------
	WatchID FileWatcherWin32::addWatch(const String& directory, FileWatchListener* watcher, bool recursive)
	{
		WatchStruct* watch = CreateWatch(directory.c_str(), recursive,
			FILE_NOTIFY_CHANGE_LAST_WRITE | FILE_NOTIFY_CHANGE_CREATION | FILE_NOTIFY_CHANGE_SIZE | FILE_NOTIFY_CHANGE_FILE_NAME);

         #ifdef WIN32_FW_USE_FINDFIRST_API
            WatchID watchid = (unsigned long)fw.add( directory.m_string );
        #else
            WatchID watchid = ++mLastWatchID;
        #endif

		if(watch)
		{
			watch->mWatchid = watchid;
			watch->mFileWatcher = this;
			watch->mFileWatchListener = watcher;
			watch->mDirName = new char[directory.m_string.length()+1];
			strcpy(watch->mDirName, directory.c_str());
		}


        mWatches.insert(std::make_pair(watchid, watch));



		return watchid;
	}

	//--------
	void FileWatcherWin32::removeWatch(const String& directory)
	{
		WatchMap::iterator iter = mWatches.begin();
		WatchMap::iterator end = mWatches.end();
		for(; iter != end; ++iter)
		{
			if(directory == iter->second->mDirName)
			{
				removeWatch(iter->first);
				return;
			}
		}
	}

	//--------
	void FileWatcherWin32::removeWatch(WatchID watchid)
	{
		WatchMap::iterator iter = mWatches.find(watchid);

		if(iter == mWatches.end())
			return;

		WatchStruct* watch = iter->second;

#ifdef WIN32_FW_USE_FINDFIRST_API
    fw.remove(watch->mWatchid);
#endif
		
    mWatches.erase(iter);

		DestroyWatch(watch);
	}

	//--------
	void FileWatcherWin32::update()
	{
#ifndef WIN32_FW_USE_FINDFIRST_API
		MsgWaitForMultipleObjectsEx(0, NULL, 0, QS_ALLINPUT, MWMO_ALERTABLE);
#endif

#ifdef WIN32_FW_USE_FINDFIRST_API
    static std::vector<FileWatcherWin32_AltImpl::fw_event> events;
    events.clear();

    fw.watch(events);

    for( size_t c = 0; c != events.size(); ++c )
    {
        WatchMap::iterator iter = mWatches.find(events[c].id);
		if(iter == mWatches.end())
			continue;


      switch(events[c].ty)
      {
        case FileWatcherWin32_AltImpl::CHANGE_SIZE:
        {
          std::string old_name;
          DWORD fni;
          std::string new_name = fw.get_event_filename( iter->second->mDirName, events[c].id, events[c].ty, fni, old_name );

          if( !new_name.empty() )
          {
            handleAction(iter->second, new_name.c_str(), fni );
          }

          break;
        }
        case FileWatcherWin32_AltImpl::CHANGE_FILE_NAME:
        {
          std::string old_name;
          DWORD fni;
          std::string new_name = fw.get_event_filename( iter->second->mDirName, events[c].id, events[c].ty, fni, old_name );

          if( !new_name.empty() )
          {
            //changed from-to
            if( !old_name.empty() )
            {
              handleAction(iter->second, old_name.c_str(), FILE_ACTION_RENAMED_OLD_NAME );
              handleAction(iter->second, new_name.c_str(), FILE_ACTION_RENAMED_NEW_NAME );
            }
            else
            {
              handleAction(iter->second, new_name.c_str(), fni );
            }
          }

          break;
        }
       case FileWatcherWin32_AltImpl::CHANGE_LAST_WRITE:
       case FileWatcherWin32_AltImpl::CHANGE_CREATION:
        {
          std::string old_name;
          DWORD fni;
          std::string new_name = fw.get_event_filename( iter->second->mDirName, events[c].id, events[c].ty, fni, old_name );

          if( !new_name.empty() )
          {
            handleAction(iter->second, new_name.c_str(), fni );
          }

          break;
        }
        default:
          break;
      }
    }
#endif
	}

	//--------
	void FileWatcherWin32::handleAction(WatchStruct* watch, const String& filename, unsigned long action)
	{
		Action fwAction;

		switch(action)
		{
		case FILE_ACTION_RENAMED_NEW_NAME:
		case FILE_ACTION_ADDED:
			fwAction = Actions::Add;
			break;
		case FILE_ACTION_RENAMED_OLD_NAME:
		case FILE_ACTION_REMOVED:
			fwAction = Actions::Delete;
			break;
		case FILE_ACTION_MODIFIED:
			fwAction = Actions::Modified;
			break;
		};

		watch->mFileWatchListener->handleFileAction(watch->mWatchid, watch->mDirName, filename, fwAction);
	}

};//namespace FW

#endif//_WIN32