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Diffstat (limited to 'shared/dir_watcher.cpp')
| -rw-r--r-- | shared/dir_watcher.cpp | 475 |
1 files changed, 0 insertions, 475 deletions
diff --git a/shared/dir_watcher.cpp b/shared/dir_watcher.cpp deleted file mode 100644 index 5d178734..00000000 --- a/shared/dir_watcher.cpp +++ /dev/null @@ -1,475 +0,0 @@ -// ************************************************************************** -// * This file is part of the FreeFileSync project. It is distributed under * -// * GNU General Public License: http://www.gnu.org/licenses/gpl.html * -// * Copyright (C) 2008-2011 ZenJu (zhnmju123 AT gmx.de) * -// ************************************************************************** - -#include "dir_watcher.h" -#include "last_error.h" -#include "i18n.h" -#include <algorithm> -#include "boost_thread_wrap.h" //include <boost/thread.hpp> -#include "loki/ScopeGuard.h" -#include <set> -#include <wx/log.h> //wxSafeShowMessage - -#ifdef FFS_WIN -#include "notify_removal.h" -#include <wx/msw/wrapwin.h> //includes "windows.h" -#include "long_path_prefix.h" -#include "privilege.h" - -#elif defined FFS_LINUX -#include <sys/inotify.h> -#include <fcntl.h> -#include "file_traverser.h" -#endif - - -using namespace zen; - -#ifdef FFS_WIN -namespace -{ -class SharedData -{ -public: - //context of worker thread - void addChanges(const char* buffer, DWORD bytesWritten, const Zstring& dirname) //throw () - { - boost::lock_guard<boost::mutex> dummy(lockAccess); - - std::set<Zstring>& output = changedFiles; - - if (bytesWritten == 0) //according to docu this may happen in case of internal buffer overflow: report some "dummy" change - output.insert(L"Overflow!"); - else - { - const char* bufPos = &buffer[0]; - while (true) - { - const FILE_NOTIFY_INFORMATION& notifyInfo = reinterpret_cast<const FILE_NOTIFY_INFORMATION&>(*bufPos); - - const Zstring fullname = dirname + Zstring(notifyInfo.FileName, notifyInfo.FileNameLength / sizeof(WCHAR)); - - //skip modifications sent by changed directories: reason for change, child element creation/deletion, will notify separately! - bool skip = false; - if (notifyInfo.Action == FILE_ACTION_RENAMED_OLD_NAME) //FILE_ACTION_RENAMED_NEW_NAME should suffice - skip = true; - else if (notifyInfo.Action == FILE_ACTION_MODIFIED) - { - //note: this check will not work if top watched directory has been renamed - const DWORD ret = ::GetFileAttributes(applyLongPathPrefix(fullname).c_str()); - bool isDir = ret != INVALID_FILE_ATTRIBUTES && (ret & FILE_ATTRIBUTE_DIRECTORY); //returns true for (dir-)symlinks also - skip = isDir; - } - - if (!skip) - output.insert(fullname); - - if (notifyInfo.NextEntryOffset == 0) - break; - bufPos += notifyInfo.NextEntryOffset; - } - } - } - - //context of main thread - void addChange(const Zstring& dirname) //throw () - { - boost::lock_guard<boost::mutex> dummy(lockAccess); - changedFiles.insert(dirname); - } - - - //context of main thread - void getChanges(std::vector<Zstring>& output) //throw FileError - { - boost::lock_guard<boost::mutex> dummy(lockAccess); - - //first check whether errors occured in thread - if (!errorMsg.empty()) - throw zen::FileError(errorMsg.c_str()); - - output.assign(changedFiles.begin(), changedFiles.end()); - changedFiles.clear(); - } - - - //context of worker thread - void reportError(const std::wstring& msg) //throw () - { - boost::lock_guard<boost::mutex> dummy(lockAccess); - errorMsg = cvrtString<BasicWString>(msg); - } - -private: - typedef Zbase<wchar_t> BasicWString; //thread safe string class for UI texts - - boost::mutex lockAccess; - std::set<Zstring> changedFiles; //get rid of duplicate entries (actually occur!) - BasicWString errorMsg; //non-empty if errors occured in thread -}; - - -class ReadChangesAsync -{ -public: - ReadChangesAsync(const Zstring& directory, //make sure to not leak in thread-unsafe types! - const std::shared_ptr<SharedData>& shared) : - shared_(shared), - dirname(directory) - { - //still in main thread - if (!endsWith(dirname, FILE_NAME_SEPARATOR)) - dirname += FILE_NAME_SEPARATOR; - - //these two privileges are required by ::CreateFile FILE_FLAG_BACKUP_SEMANTICS according to - //http://msdn.microsoft.com/en-us/library/aa363858(v=vs.85).aspx - try - { - Privileges::getInstance().ensureActive(SE_BACKUP_NAME); //throw FileError - Privileges::getInstance().ensureActive(SE_RESTORE_NAME); // - } - catch (const FileError&) {} - - hDir = ::CreateFile(applyLongPathPrefix(dirname.c_str()).c_str(), - FILE_LIST_DIRECTORY, - FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, - NULL, - OPEN_EXISTING, - FILE_FLAG_BACKUP_SEMANTICS | FILE_FLAG_OVERLAPPED, - NULL); - if (hDir == INVALID_HANDLE_VALUE ) - throw FileError(_("Could not initialize directory monitoring:") + "\n\"" + utf8CvrtTo<std::wstring>(dirname) + "\"" + "\n\n" + zen::getLastErrorFormatted()); - - //Loki::ScopeGuard guardDir = Loki::MakeGuard(::CloseHandle, hDir); - //guardDir.Dismiss(); - } - - ~ReadChangesAsync() - { - if (hDir != INVALID_HANDLE_VALUE) - ::CloseHandle(hDir); - } - - void operator()() //thread entry - { - try - { - std::vector<char> buffer(64 * 1024); //needs to be aligned on a DWORD boundary; maximum buffer size restricted by some networks protocols (according to docu) - - while (true) - { - boost::this_thread::interruption_point(); - - //actual work - OVERLAPPED overlapped = {}; - overlapped.hEvent = ::CreateEvent(NULL, //__in_opt LPSECURITY_ATTRIBUTES lpEventAttributes, - true, //__in BOOL bManualReset, - false, //__in BOOL bInitialState, - NULL); //__in_opt LPCTSTR lpName - if (overlapped.hEvent == NULL) - return shared_->reportError(_("Error when monitoring directories.") + " (CreateEvent)" + "\n\n" + getLastErrorFormatted()); //throw () + quit thread - - Loki::ScopeGuard dummy = Loki::MakeGuard(::CloseHandle, overlapped.hEvent); - (void)dummy; - - //asynchronous variant: runs on this thread's APC queue! - if (!::ReadDirectoryChangesW(hDir, // __in HANDLE hDirectory, - &buffer[0], // __out LPVOID lpBuffer, - static_cast<DWORD>(buffer.size()), // __in DWORD nBufferLength, - true, // __in BOOL bWatchSubtree, - FILE_NOTIFY_CHANGE_FILE_NAME | - FILE_NOTIFY_CHANGE_DIR_NAME | - FILE_NOTIFY_CHANGE_SIZE | - FILE_NOTIFY_CHANGE_LAST_WRITE, // __in DWORD dwNotifyFilter, - NULL, // __out_opt LPDWORD lpBytesReturned, - &overlapped, // __inout_opt LPOVERLAPPED lpOverlapped, - NULL)) // __in_opt LPOVERLAPPED_COMPLETION_ROUTINE lpCompletionRoutine - return shared_->reportError(_("Error when monitoring directories.") + " (ReadDirectoryChangesW)" + "\n\n" + getLastErrorFormatted()); //throw () + quit thread - - //async I/O is a resource that needs to be guarded since it will write to local variable "buffer"! - Loki::ScopeGuard lockAio = Loki::MakeGuard([&]() - { - //http://msdn.microsoft.com/en-us/library/aa363789(v=vs.85).aspx - if (::CancelIo(hDir) == TRUE) //cancel all async I/O related to this handle and thread - { - DWORD bytesWritten = 0; - ::GetOverlappedResult(hDir, &overlapped, &bytesWritten, true); //wait until cancellation is complete - } - }); - - DWORD bytesWritten = 0; - - //wait for results - while (!::GetOverlappedResult(hDir, //__in HANDLE hFile, - &overlapped, //__in LPOVERLAPPED lpOverlapped, - &bytesWritten, //__out LPDWORD lpNumberOfBytesTransferred, - false)) //__in BOOL bWait - { - if (::GetLastError() != ERROR_IO_INCOMPLETE) - return shared_->reportError(_("Error when monitoring directories.") + " (GetOverlappedResult)" + "\n\n" + getLastErrorFormatted()); //throw () + quit thread - - //execute asynchronous procedure calls (APC) queued on this thread - ::SleepEx(50, // __in DWORD dwMilliseconds, - true); // __in BOOL bAlertable - - boost::this_thread::interruption_point(); - } - lockAio.Dismiss(); - - shared_->addChanges(&buffer[0], bytesWritten, dirname); //throw () - } - } - catch (boost::thread_interrupted&) - { - throw; //this is the only reasonable exception! - } - catch (...) //exceptions must be catched per thread - { - wxSafeShowMessage(wxString(_("An exception occurred!")) + wxT("(Dir Watcher)"), wxT("Unknown exception in worker thread!")); //simple wxMessageBox won't do for threads - } - } - - ReadChangesAsync(ReadChangesAsync && other) : - hDir(INVALID_HANDLE_VALUE) - { - shared_ = std::move(other.shared_); - dirname = std::move(other.dirname); - std::swap(hDir, other.hDir); - } - - HANDLE getDirHandle() const { return hDir; } //for reading purposes only, don't abuse (e.g. close handle)! - -private: - //shared between main and worker: - std::shared_ptr<SharedData> shared_; - //worker thread only: - Zstring dirname; //thread safe! - HANDLE hDir; -}; - - -class HandleVolumeRemoval : public NotifyRequestDeviceRemoval -{ -public: - HandleVolumeRemoval(HANDLE hDir, - boost::thread& worker, - const std::shared_ptr<SharedData>& shared, - const Zstring& dirname) : - NotifyRequestDeviceRemoval(hDir), //throw FileError - worker_(worker), - shared_(shared), - dirname_(dirname), - removalRequested(false), - operationComplete(false) {} - - //all functions are called by main thread! - - bool requestReceived() const { return removalRequested; } - bool finished() const { return operationComplete; } - -private: - virtual void onRequestRemoval(HANDLE hnd) - { - //must release hDir immediately! - worker_.interrupt(); - worker_.join(); - //now hDir should have been released - - //report removal as change to main directory - shared_->addChange(dirname_); - - removalRequested = true; - } //don't throw! - virtual void onRemovalFinished(HANDLE hnd, bool successful) { operationComplete = true; } //throw()! - - boost::thread& worker_; - std::shared_ptr<SharedData> shared_; - Zstring dirname_; - bool removalRequested; - bool operationComplete; -}; -} - - -struct DirWatcher::Pimpl -{ - boost::thread worker; - std::shared_ptr<SharedData> shared; - - std::unique_ptr<HandleVolumeRemoval> volRemoval; -}; - - -DirWatcher::DirWatcher(const Zstring& directory) : //throw FileError - pimpl_(new Pimpl) -{ - pimpl_->shared = std::make_shared<SharedData>(); - - ReadChangesAsync reader(directory, pimpl_->shared); //throw FileError - pimpl_->volRemoval.reset(new HandleVolumeRemoval(reader.getDirHandle(), pimpl_->worker, pimpl_->shared, directory)); //throw FileError - pimpl_->worker = boost::thread(std::move(reader)); -} - - -DirWatcher::~DirWatcher() -{ - pimpl_->worker.interrupt(); - //pimpl_->worker.join(); -> we don't have time to wait... will take ~50ms anyway - //caveat: exitting the app may simply kill this thread! - - //wait until device removal is confirmed, to (hopefully!) prevent locking hDir again by new watch! - if (pimpl_->volRemoval->requestReceived()) - { - const boost::system_time maxwait = boost::get_system_time() + boost::posix_time::seconds(3); //HandleVolumeRemoval::finished() not guaranteed! - - while (!pimpl_->volRemoval->finished() && boost::get_system_time() < maxwait) - boost::thread::sleep(boost::get_system_time() + boost::posix_time::milliseconds(50)); - } -} - - -std::vector<Zstring> DirWatcher::getChanges() //throw FileError -{ - std::vector<Zstring> output; - pimpl_->shared->getChanges(output); //throw FileError - return output; -} - - -#elif defined FFS_LINUX -struct DirWatcher::Pimpl -{ - int notifDescr; - std::map<int, Zstring> watchDescrs; //watch descriptor and corresponding directory name (postfixed with separator!) -}; - - -namespace -{ -class DirsOnlyTraverser : public zen::TraverseCallback -{ -public: - DirsOnlyTraverser(std::vector<Zstring>& dirs) : dirs_(dirs) {} - - virtual void onFile (const Zchar* shortName, const Zstring& fullName, const FileInfo& details) {} - virtual void onSymlink(const Zchar* shortName, const Zstring& fullName, const SymlinkInfo& details) {} - virtual ReturnValDir onDir (const Zchar* shortName, const Zstring& fullName) - { - dirs_.push_back(fullName); - return ReturnValDir(Loki::Int2Type<ReturnValDir::TRAVERSING_DIR_CONTINUE>(), *this); - } - virtual HandleError onError(const std::wstring& errorText) { throw FileError(errorText); } - -private: - std::vector<Zstring>& dirs_; -}; -} - - -DirWatcher::DirWatcher(const Zstring& directory) : //throw FileError - pimpl_(new Pimpl) -{ - //still in main thread - Zstring dirname = directory; - if (endsWith(dirname, FILE_NAME_SEPARATOR)) - dirname.resize(dirname.size() - 1); - - //get all subdirectories - std::vector<Zstring> fullDirList; - fullDirList.push_back(dirname); - - DirsOnlyTraverser traverser(fullDirList); //throw FileError - zen::traverseFolder(dirname, false, traverser); //don't traverse into symlinks (analog to windows build) - - //init - pimpl_->notifDescr = ::inotify_init(); - if (pimpl_->notifDescr == -1) - throw FileError(_("Could not initialize directory monitoring:") + "\n\"" + dirname + "\"" + "\n\n" + getLastErrorFormatted()); - - Loki::ScopeGuard guardDescr = Loki::MakeGuard(::close, pimpl_->notifDescr); - - //set non-blocking mode - bool initSuccess = false; - int flags = ::fcntl(pimpl_->notifDescr, F_GETFL); - if (flags != -1) - initSuccess = ::fcntl(pimpl_->notifDescr, F_SETFL, flags | O_NONBLOCK) != -1; - - if (!initSuccess) - throw FileError(_("Could not initialize directory monitoring:") + "\n\"" + dirname + "\"" + "\n\n" + getLastErrorFormatted()); - - //add watches - std::for_each(fullDirList.begin(), fullDirList.end(), - [&](Zstring subdir) - { - int wd = ::inotify_add_watch(pimpl_->notifDescr, subdir.c_str(), - IN_ONLYDIR | //watch directories only - IN_DONT_FOLLOW | //don't follow symbolic links - IN_MODIFY | - IN_CLOSE_WRITE | - IN_MOVE | - IN_CREATE | - IN_DELETE | - IN_DELETE_SELF | - IN_MOVE_SELF); - if (wd == -1) - throw FileError(_("Could not initialize directory monitoring:") + "\n\"" + subdir + "\"" + "\n\n" + getLastErrorFormatted()); - - if (!endsWith(subdir, FILE_NAME_SEPARATOR)) - subdir += FILE_NAME_SEPARATOR; - pimpl_->watchDescrs.insert(std::make_pair(wd, subdir)); - }); - - guardDescr.Dismiss(); -} - - -DirWatcher::~DirWatcher() -{ - ::close(pimpl_->notifDescr); //associated watches are removed automatically! -} - - -std::vector<Zstring> DirWatcher::getChanges() //throw FileError -{ - std::vector<char> buffer(1024 * (sizeof(struct inotify_event) + 16)); - - //non-blocking call, see O_NONBLOCK - ssize_t bytesRead = ::read(pimpl_->notifDescr, &buffer[0], buffer.size()); - - if (bytesRead == -1) - { - if (errno == EINTR || //Interrupted function call; When this happens, you should try the call again. - errno == EAGAIN) //Non-blocking I/O has been selected using O_NONBLOCK and no data was immediately available for reading - return std::vector<Zstring>(); - - throw FileError(_("Error when monitoring directories.") + "\n\n" + getLastErrorFormatted()); - } - - std::set<Zstring> tmp; //get rid of duplicate entries (actually occur!) - - ssize_t bytePos = 0; - while (bytePos < bytesRead) - { - struct inotify_event& evt = reinterpret_cast<struct inotify_event&>(buffer[bytePos]); - - if (evt.len != 0) //exclude case: deletion of "self", already reported by parent directory watch - { - auto iter = pimpl_->watchDescrs.find(evt.wd); - if (iter != pimpl_->watchDescrs.end()) - { - //Note: evt.len is NOT the size of the evt.name c-string, but the array size including all padding 0 characters! - //It may be even 0 in which case evt.name must not be used! - tmp.insert(iter->second + evt.name); - } - } - - bytePos += sizeof(struct inotify_event) + evt.len; - } - - return std::vector<Zstring>(tmp.begin(), tmp.end()); -} - -#endif |