// ************************************************************************** // * 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) Zenju (zenju AT gmx DOT de) - All Rights Reserved * // ************************************************************************** #include "file_handling.h" #include #include #include #include "file_traverser.h" #include "scope_guard.h" #include "symlink_target.h" #include "file_io.h" #include "assert_static.h" #include "file_id_def.h" #include #ifdef FFS_WIN #include #include "privilege.h" #include "dll.h" #include "win.h" //includes "windows.h" #include "long_path_prefix.h" #include "dst_hack.h" #include "win_ver.h" #include "IFileOperation/file_op.h" #elif defined FFS_LINUX #include //statfs #include //AT_SYMLINK_NOFOLLOW, UTIME_OMIT #ifdef HAVE_SELINUX #include #endif #elif defined FFS_MAC #include //statfs #include #endif #if defined FFS_LINUX || defined FFS_MAC #include //#include #endif using namespace zen; bool zen::fileExists(const Zstring& filename) { //symbolic links (broken or not) are also treated as existing files! #ifdef FFS_WIN const DWORD ret = ::GetFileAttributes(applyLongPathPrefix(filename).c_str()); return ret != INVALID_FILE_ATTRIBUTES && (ret & FILE_ATTRIBUTE_DIRECTORY) == 0; //returns true for (file-)symlinks also #elif defined FFS_LINUX || defined FFS_MAC struct stat fileInfo = {}; return ::lstat(filename.c_str(), &fileInfo) == 0 && (S_ISLNK(fileInfo.st_mode) || S_ISREG(fileInfo.st_mode)); //in Linux a symbolic link is neither file nor directory #endif } bool zen::dirExists(const Zstring& dirname) { //symbolic links (broken or not) are also treated as existing directories! #ifdef FFS_WIN const DWORD ret = ::GetFileAttributes(applyLongPathPrefix(dirname).c_str()); return ret != INVALID_FILE_ATTRIBUTES && (ret & FILE_ATTRIBUTE_DIRECTORY) != 0; //returns true for (dir-)symlinks also #elif defined FFS_LINUX || defined FFS_MAC struct stat dirInfo = {}; return ::lstat(dirname.c_str(), &dirInfo) == 0 && (S_ISLNK(dirInfo.st_mode) || S_ISDIR(dirInfo.st_mode)); //in Linux a symbolic link is neither file nor directory #endif } bool zen::symlinkExists(const Zstring& linkname) { #ifdef FFS_WIN WIN32_FIND_DATA fileInfo = {}; { const HANDLE searchHandle = ::FindFirstFile(applyLongPathPrefix(linkname).c_str(), &fileInfo); if (searchHandle == INVALID_HANDLE_VALUE) return false; ::FindClose(searchHandle); } return isSymlink(fileInfo); #elif defined FFS_LINUX || defined FFS_MAC struct stat fileInfo = {}; return ::lstat(linkname.c_str(), &fileInfo) == 0 && S_ISLNK(fileInfo.st_mode); //symbolic link #endif } bool zen::somethingExists(const Zstring& objname) { #ifdef FFS_WIN const DWORD rv = ::GetFileAttributes(applyLongPathPrefix(objname).c_str()); return rv != INVALID_FILE_ATTRIBUTES || ::GetLastError() == ERROR_SHARING_VIOLATION; //"C:\pagefile.sys" #elif defined FFS_LINUX || defined FFS_MAC struct stat fileInfo = {}; return ::lstat(objname.c_str(), &fileInfo) == 0; #endif } namespace { void getFileAttrib(const Zstring& filename, FileAttrib& attr, ProcSymlink procSl) //throw FileError { #ifdef FFS_WIN WIN32_FIND_DATA fileInfo = {}; { const HANDLE searchHandle = ::FindFirstFile(applyLongPathPrefix(filename).c_str(), &fileInfo); if (searchHandle == INVALID_HANDLE_VALUE) throw FileError(replaceCpy(_("Cannot read file attributes of %x."), L"%x", fmtFileName(filename)) + L"\n\n" + getLastErrorFormatted()); ::FindClose(searchHandle); } // WIN32_FILE_ATTRIBUTE_DATA sourceAttr = {}; // if (!::GetFileAttributesEx(applyLongPathPrefix(sourceObj).c_str(), //__in LPCTSTR lpFileName, // GetFileExInfoStandard, //__in GET_FILEEX_INFO_LEVELS fInfoLevelId, // &sourceAttr)) //__out LPVOID lpFileInformation if (!isSymlink(fileInfo) || procSl == SYMLINK_DIRECT) { //####################################### DST hack ########################################### const bool isDirectory = (fileInfo.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY) != 0; if (!isDirectory && dst::isFatDrive(filename)) //throw() { const dst::RawTime rawTime(fileInfo.ftCreationTime, fileInfo.ftLastWriteTime); if (dst::fatHasUtcEncoded(rawTime)) //throw std::runtime_error { fileInfo.ftLastWriteTime = dst::fatDecodeUtcTime(rawTime); //return last write time in real UTC, throw (std::runtime_error) ::GetSystemTimeAsFileTime(&fileInfo.ftCreationTime); //real creation time information is not available... } } //####################################### DST hack ########################################### attr.fileSize = UInt64(fileInfo.nFileSizeLow, fileInfo.nFileSizeHigh); attr.modificationTime = toTimeT(fileInfo.ftLastWriteTime); } else { const HANDLE hFile = ::CreateFile(applyLongPathPrefix(filename).c_str(), //open handle to target of symbolic link 0, FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, nullptr, OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, //needed to open a directory nullptr); if (hFile == INVALID_HANDLE_VALUE) throw FileError(replaceCpy(_("Cannot read file attributes of %x."), L"%x", fmtFileName(filename)) + L"\n\n" + getLastErrorFormatted()); ZEN_ON_SCOPE_EXIT(::CloseHandle(hFile)); BY_HANDLE_FILE_INFORMATION fileInfoHnd = {}; if (!::GetFileInformationByHandle(hFile, &fileInfoHnd)) throw FileError(replaceCpy(_("Cannot read file attributes of %x."), L"%x", fmtFileName(filename)) + L"\n\n" + getLastErrorFormatted()); attr.fileSize = UInt64(fileInfoHnd.nFileSizeLow, fileInfoHnd.nFileSizeHigh); attr.modificationTime = toTimeT(fileInfoHnd.ftLastWriteTime); } #elif defined FFS_LINUX || defined FFS_MAC struct stat fileInfo = {}; const int rv = procSl == SYMLINK_FOLLOW ? :: stat(filename.c_str(), &fileInfo) : ::lstat(filename.c_str(), &fileInfo); if (rv != 0) //follow symbolic links throw FileError(replaceCpy(_("Cannot read file attributes of %x."), L"%x", fmtFileName(filename)) + L"\n\n" + getLastErrorFormatted()); attr.fileSize = UInt64(fileInfo.st_size); attr.modificationTime = fileInfo.st_mtime; #endif } } UInt64 zen::getFilesize(const Zstring& filename) //throw FileError { FileAttrib attr; getFileAttrib(filename, attr, SYMLINK_FOLLOW); //throw FileError return attr.fileSize; } Int64 zen::getFileTime(const Zstring& filename, ProcSymlink procSl) //throw FileError { FileAttrib attr; getFileAttrib(filename, attr, procSl); //throw FileError return attr.modificationTime; } UInt64 zen::getFreeDiskSpace(const Zstring& path) //throw FileError { #ifdef FFS_WIN ULARGE_INTEGER bytesFree = {}; if (!::GetDiskFreeSpaceEx(appendSeparator(path).c_str(), //__in_opt LPCTSTR lpDirectoryName, -> "UNC name [...] must include a trailing backslash, for example, "\\MyServer\MyShare\" &bytesFree, //__out_opt PULARGE_INTEGER lpFreeBytesAvailable, nullptr, //__out_opt PULARGE_INTEGER lpTotalNumberOfBytes, nullptr)) //__out_opt PULARGE_INTEGER lpTotalNumberOfFreeBytes throw FileError(replaceCpy(_("Cannot read file attributes of %x."), L"%x", fmtFileName(path)) + L"\n\n" + getLastErrorFormatted()); return UInt64(bytesFree.LowPart, bytesFree.HighPart); #elif defined FFS_LINUX || defined FFS_MAC struct statfs info = {}; if (::statfs(path.c_str(), &info) != 0) throw FileError(replaceCpy(_("Cannot read file attributes of %x."), L"%x", fmtFileName(path)) + L"\n\n" + getLastErrorFormatted()); return UInt64(info.f_bsize) * info.f_bavail; #endif } namespace { #ifdef FFS_WIN //(try to) enhance error messages by showing which processes lock the file Zstring getLockingProcessNames(const Zstring& filename) //throw(), empty string if none found or error occurred { if (vistaOrLater()) { using namespace fileop; const DllFun getLockingProcesses(getDllName(), funName_getLockingProcesses); const DllFun freeString (getDllName(), funName_freeString); if (getLockingProcesses && freeString) { const wchar_t* procList = nullptr; if (getLockingProcesses(filename.c_str(), procList)) { ZEN_ON_SCOPE_EXIT(freeString(procList)); return procList; } } } return Zstring(); } DWORD retrieveVolumeSerial(const Zstring& pathName) //return 0 on error! { //note: this even works for network shares: \\share\dirname const DWORD bufferSize = 10000; std::vector buffer(bufferSize); //full pathName need not yet exist! if (!::GetVolumePathName(pathName.c_str(), //__in LPCTSTR lpszFileName, &buffer[0], //__out LPTSTR lpszVolumePathName, bufferSize)) //__in DWORD cchBufferLength return 0; DWORD volumeSerial = 0; if (!::GetVolumeInformation(&buffer[0], //__in_opt LPCTSTR lpRootPathName, nullptr, //__out LPTSTR lpVolumeNameBuffer, 0, //__in DWORD nVolumeNameSize, &volumeSerial, //__out_opt LPDWORD lpVolumeSerialNumber, nullptr, //__out_opt LPDWORD lpMaximumComponentLength, nullptr, //__out_opt LPDWORD lpFileSystemFlags, nullptr, //__out LPTSTR lpFileSystemNameBuffer, 0)) //__in DWORD nFileSystemNameSize return 0; return volumeSerial; } #elif defined FFS_LINUX || defined FFS_MAC dev_t retrieveVolumeSerial(const Zstring& pathName) //return 0 on error! { Zstring volumePathName = pathName; //remove trailing slash if (volumePathName.size() > 1 && endsWith(volumePathName, FILE_NAME_SEPARATOR)) //exception: allow '/' volumePathName = beforeLast(volumePathName, FILE_NAME_SEPARATOR); struct stat fileInfo = {}; while (::lstat(volumePathName.c_str(), &fileInfo) != 0) //go up in folder hierarchy until existing folder is found { volumePathName = beforeLast(volumePathName, FILE_NAME_SEPARATOR); //returns empty string if ch not found if (volumePathName.empty()) return 0; //this includes path "/" also! } return fileInfo.st_dev; } #endif } zen::ResponseSame zen::onSameVolume(const Zstring& folderLeft, const Zstring& folderRight) //throw() { const auto serialLeft = retrieveVolumeSerial(folderLeft); //returns 0 on error! const auto serialRight = retrieveVolumeSerial(folderRight); //returns 0 on error! if (serialLeft == 0 || serialRight == 0) return IS_SAME_CANT_SAY; return serialLeft == serialRight ? IS_SAME_YES : IS_SAME_NO; } bool zen::removeFile(const Zstring& filename) //throw FileError { #ifdef FFS_WIN const Zstring& filenameFmt = applyLongPathPrefix(filename); if (!::DeleteFile(filenameFmt.c_str())) #elif defined FFS_LINUX || defined FFS_MAC if (::unlink(filename.c_str()) != 0) #endif { ErrorCode lastError = getLastError(); if (errorCodeForNotExisting(lastError)) //no error situation if file is not existing! manual deletion relies on it! return false; #ifdef FFS_WIN if (lastError == ERROR_ACCESS_DENIED) //function fails if file is read-only { ::SetFileAttributes(filenameFmt.c_str(), FILE_ATTRIBUTE_NORMAL); //(try to) normalize file attributes if (::DeleteFile(filenameFmt.c_str())) //now try again... return true; lastError = ::GetLastError(); } #endif //after "lastError" evaluation it *may* be redundant to check existence again, but better be safe than sorry: if (!somethingExists(filename)) //warning: changes global error code!! return false; //neither file nor any other object (e.g. broken symlink) with that name existing //begin of "regular" error reporting const std::wstring shortMsg = replaceCpy(_("Cannot delete file %x."), L"%x", fmtFileName(filename)); #ifdef FFS_WIN if (lastError == ERROR_SHARING_VIOLATION || //-> enhance error message! lastError == ERROR_LOCK_VIOLATION) { const Zstring procList = getLockingProcessNames(filename); //throw() if (!procList.empty()) throw FileError(shortMsg + L"\n\n" + _("The file is locked by another process:") + L"\n" + procList); } #endif throw FileError(shortMsg + L"\n\n" + getLastErrorFormatted(lastError)); } return true; } namespace { /* Usage overview: (avoid circular pattern!) renameFile() --> renameFile_sub() | /|\ \|/ | Fix8Dot3NameClash() */ //wrapper for file system rename function: void renameFile_sub(const Zstring& oldName, const Zstring& newName) //throw FileError, ErrorDifferentVolume, ErrorTargetExisting { #ifdef FFS_WIN const Zstring oldNameFmt = applyLongPathPrefix(oldName); const Zstring newNameFmt = applyLongPathPrefix(newName); if (!::MoveFileEx(oldNameFmt.c_str(), //__in LPCTSTR lpExistingFileName, newNameFmt.c_str(), //__in_opt LPCTSTR lpNewFileName, 0)) //__in DWORD dwFlags { DWORD lastError = ::GetLastError(); const std::wstring shortMsg = replaceCpy(replaceCpy(_("Cannot move file %x to %y."), L"%x", L"\n" + fmtFileName(oldName)), L"%y", L"\n" + fmtFileName(newName)); if (lastError == ERROR_SHARING_VIOLATION || //-> enhance error message! lastError == ERROR_LOCK_VIOLATION) { const Zstring procList = getLockingProcessNames(oldName); //throw() if (!procList.empty()) throw FileError(shortMsg + L"\n\n" + _("The file is locked by another process:") + L"\n" + procList); } if (lastError == ERROR_ACCESS_DENIED) //MoveFileEx may fail to rename a read-only file on a SAMBA-share -> (try to) handle this { const DWORD oldAttr = ::GetFileAttributes(oldNameFmt.c_str()); if (oldAttr != INVALID_FILE_ATTRIBUTES && (oldAttr & FILE_ATTRIBUTE_READONLY)) { if (::SetFileAttributes(oldNameFmt.c_str(), FILE_ATTRIBUTE_NORMAL)) //remove readonly-attribute { //try again... if (::MoveFileEx(oldNameFmt.c_str(), //__in LPCTSTR lpExistingFileName, newNameFmt.c_str(), //__in_opt LPCTSTR lpNewFileName, 0)) //__in DWORD dwFlags { //(try to) restore file attributes ::SetFileAttributes(newNameFmt.c_str(), oldAttr); //don't handle error return; } else { lastError = ::GetLastError(); //use error code from second call to ::MoveFileEx() //cleanup: (try to) restore file attributes: assume oldName is still existing ::SetFileAttributes(oldNameFmt.c_str(), oldAttr); } } } } std::wstring errorMessage = shortMsg + L"\n\n" + getLastErrorFormatted(lastError); if (lastError == ERROR_NOT_SAME_DEVICE) throw ErrorDifferentVolume(errorMessage); else if (lastError == ERROR_ALREADY_EXISTS || //-> used on Win7 x64 lastError == ERROR_FILE_EXISTS) //-> used by XP??? throw ErrorTargetExisting(errorMessage); else throw FileError(errorMessage); } #elif defined FFS_LINUX || defined FFS_MAC if (::rename(oldName.c_str(), newName.c_str()) != 0) { const int lastError = errno; std::wstring errorMessage = replaceCpy(replaceCpy(_("Cannot move file %x to %y."), L"%x", L"\n" + fmtFileName(oldName)), L"%y", L"\n" + fmtFileName(newName)) + L"\n\n" + getLastErrorFormatted(lastError); if (lastError == EXDEV) throw ErrorDifferentVolume(errorMessage); else if (lastError == EEXIST) throw ErrorTargetExisting(errorMessage); else throw FileError(errorMessage); } #endif } #ifdef FFS_WIN /*small wrapper around ::GetShortPathName() ::GetLongPathName() */ template Zstring getFilenameFmt(const Zstring& filename, Function fun) //throw(); returns empty string on error { const Zstring filenameFmt = applyLongPathPrefix(filename); const DWORD bufferSize = fun(filenameFmt.c_str(), nullptr, 0); if (bufferSize == 0) return Zstring(); std::vector buffer(bufferSize); const DWORD rv = fun(filenameFmt.c_str(), //__in LPCTSTR lpszShortPath, &buffer[0], //__out LPTSTR lpszLongPath, bufferSize); //__in DWORD cchBuffer if (rv == 0 || rv >= bufferSize) return Zstring(); return &buffer[0]; } Zstring findUnused8Dot3Name(const Zstring& filename) //find a unique 8.3 short name { const Zstring pathPrefix = contains(filename, FILE_NAME_SEPARATOR) ? (beforeLast(filename, FILE_NAME_SEPARATOR) + FILE_NAME_SEPARATOR) : Zstring(); Zstring extension = afterLast(afterLast(filename, FILE_NAME_SEPARATOR), Zchar('.')); //extension needn't contain reasonable data if (extension.empty()) extension = Zstr("FFS"); else if (extension.length() > 3) extension.resize(3); for (int index = 0; index < 100000000; ++index) //filename must be representable by <= 8 characters { const Zstring output = pathPrefix + numberTo(index) + Zchar('.') + extension; if (!somethingExists(output)) //ensure uniqueness return output; } throw std::runtime_error(std::string("100000000 files, one for each number, exist in this directory? You're kidding...") + utfCvrtTo(pathPrefix)); } bool have8dot3NameClash(const Zstring& filename) { if (!contains(filename, FILE_NAME_SEPARATOR)) return false; if (somethingExists(filename)) //name OR directory! { const Zstring origName = afterLast(filename, FILE_NAME_SEPARATOR); //returns the whole string if ch not found const Zstring shortName = afterLast(getFilenameFmt(filename, ::GetShortPathName), FILE_NAME_SEPARATOR); //throw() returns empty string on error const Zstring longName = afterLast(getFilenameFmt(filename, ::GetLongPathName) , FILE_NAME_SEPARATOR); // if (!shortName.empty() && !longName.empty() && EqualFilename()(origName, shortName) && !EqualFilename()(shortName, longName)) { //for filename short and long file name are equal and another unrelated file happens to have the same short name //e.g. filename == "TESTWE~1", but another file is existing named "TestWeb" with short name ""TESTWE~1" return true; } } return false; } class Fix8Dot3NameClash //throw FileError { public: Fix8Dot3NameClash(const Zstring& filename) { const Zstring longName = afterLast(getFilenameFmt(filename, ::GetLongPathName), FILE_NAME_SEPARATOR); //throw() returns empty string on error unrelatedFile = beforeLast(filename, FILE_NAME_SEPARATOR) + FILE_NAME_SEPARATOR + longName; //find another name in short format: this ensures the actual short name WILL be renamed as well! unrelatedFileParked = findUnused8Dot3Name(filename); //move already existing short name out of the way for now renameFile_sub(unrelatedFile, unrelatedFileParked); //throw FileError, ErrorDifferentVolume //DON'T call renameFile() to avoid reentrance! } ~Fix8Dot3NameClash() { //the file system should assign this unrelated file a new (unique) short name try { renameFile_sub(unrelatedFileParked, unrelatedFile); //throw FileError, ErrorDifferentVolume } catch (...) {} } private: Zstring unrelatedFile; Zstring unrelatedFileParked; }; #endif } //rename file: no copying!!! void zen::renameFile(const Zstring& oldName, const Zstring& newName) //throw FileError, ErrorDifferentVolume, ErrorTargetExisting { try { renameFile_sub(oldName, newName); //throw FileError, ErrorDifferentVolume, ErrorTargetExisting } catch (const ErrorTargetExisting&) { #ifdef FFS_WIN //try to handle issues with already existing short 8.3 file names on Windows if (have8dot3NameClash(newName)) { Fix8Dot3NameClash dummy(newName); //throw FileError; move clashing filename to the side //now try again... renameFile_sub(oldName, newName); //throw FileError return; } #endif throw; } } namespace { class CollectFilesFlat : public zen::TraverseCallback { public: CollectFilesFlat(std::vector& files, std::vector& dirs) : m_files(files), m_dirs(dirs) {} virtual void onFile(const Zchar* shortName, const Zstring& fullName, const FileInfo& details) { m_files.push_back(fullName); } virtual HandleLink onSymlink(const Zchar* shortName, const Zstring& fullName, const SymlinkInfo& details) { if (details.dirLink) m_dirs.push_back(fullName); else m_files.push_back(fullName); return LINK_SKIP; } virtual std::shared_ptr onDir(const Zchar* shortName, const Zstring& fullName) { m_dirs.push_back(fullName); return nullptr; //DON'T traverse into subdirs; removeDirectory works recursively! } virtual HandleError onError(const std::wstring& msg) { throw FileError(msg); } private: CollectFilesFlat(const CollectFilesFlat&); CollectFilesFlat& operator=(const CollectFilesFlat&); std::vector& m_files; std::vector& m_dirs; }; void removeDirectoryImpl(const Zstring& directory, CallbackRemoveDir* callback) //throw FileError { assert(somethingExists(directory)); //[!] #ifdef FFS_WIN const Zstring directoryFmt = applyLongPathPrefix(directory); //support for \\?\-prefix //(try to) normalize file attributes: actually NEEDED for symbolic links also! ::SetFileAttributes(directoryFmt.c_str(), FILE_ATTRIBUTE_NORMAL); #endif //attention: check if directory is a symlink! Do NOT traverse into it deleting contained files!!! if (symlinkExists(directory)) //remove symlink directly { if (callback) callback->onBeforeDirDeletion(directory); //once per symlink #ifdef FFS_WIN if (!::RemoveDirectory(directoryFmt.c_str())) #elif defined FFS_LINUX || defined FFS_MAC if (::unlink(directory.c_str()) != 0) #endif throw FileError(replaceCpy(_("Cannot delete directory %x."), L"%x", fmtFileName(directory)) + L"\n\n" + getLastErrorFormatted()); } else { std::vector fileList; std::vector dirList; { //get all files and directories from current directory (WITHOUT subdirectories!) CollectFilesFlat cff(fileList, dirList); traverseFolder(directory, cff); //don't follow symlinks } //delete directories recursively std::for_each(dirList.begin(), dirList.end(), [&](const Zstring& dirname) { removeDirectoryImpl(dirname, callback); //throw FileError; call recursively to correctly handle symbolic links }); //delete files std::for_each(fileList.begin(), fileList.end(), [&](const Zstring& filename) { if (callback) callback->onBeforeFileDeletion(filename); //call once per file removeFile(filename); //throw FileError }); //parent directory is deleted last if (callback) callback->onBeforeDirDeletion(directory); //and once per folder #ifdef FFS_WIN if (!::RemoveDirectory(directoryFmt.c_str())) #elif defined FFS_LINUX || defined FFS_MAC if (::rmdir(directory.c_str()) != 0) #endif throw FileError(replaceCpy(_("Cannot delete directory %x."), L"%x", fmtFileName(directory)) + L"\n\n" + getLastErrorFormatted()); //may spuriously fail with ERROR_DIR_NOT_EMPTY(145) even though all child items have //successfully been *marked* for deletion, but some application still has a handle open! //e.g. Open "C:\Test\Dir1\Dir2" (filled with lots of files) in Explorer, then delete "C:\Test\Dir1" via ::RemoveDirectory() => Error 145 //Sample code: http://us.generation-nt.com/answer/createfile-directory-handles-removing-parent-help-29126332.html } } } void zen::removeDirectory(const Zstring& directory, CallbackRemoveDir* callback) { //no error situation if directory is not existing! manual deletion relies on it! if (!somethingExists(directory)) return; //neither directory nor any other object (e.g. broken symlink) with that name existing removeDirectoryImpl(directory, callback); } void zen::setFileTime(const Zstring& filename, const Int64& modTime, ProcSymlink procSl) //throw FileError { #ifdef FFS_WIN FILETIME creationTime = {}; FILETIME lastWriteTime = tofiletime(modTime); //####################################### DST hack ########################################### if (dst::isFatDrive(filename)) //throw() { const dst::RawTime encodedTime = dst::fatEncodeUtcTime(lastWriteTime); //throw std::runtime_error creationTime = encodedTime.createTimeRaw; lastWriteTime = encodedTime.writeTimeRaw; } //####################################### DST hack ########################################### { //extra scope for debug check below //privilege SE_BACKUP_NAME doesn't seem to be required here for symbolic links //note: setting privileges requires admin rights! //opening newly created target file may fail due to some AV-software scanning it: no error, we will wait! //http://support.microsoft.com/?scid=kb%3Ben-us%3B316609&x=17&y=20 //-> enable as soon it turns out it is required! /*const int retryInterval = 50; const int maxRetries = 2000 / retryInterval; for (int i = 0; i < maxRetries; ++i) { */ /* if (hTarget == INVALID_HANDLE_VALUE && ::GetLastError() == ERROR_SHARING_VIOLATION) ::Sleep(retryInterval); //wait then retry else //success or unknown failure break; } */ //temporarily reset read-only flag if required DWORD attribs = INVALID_FILE_ATTRIBUTES; ZEN_ON_SCOPE_EXIT( if (attribs != INVALID_FILE_ATTRIBUTES) ::SetFileAttributes(applyLongPathPrefix(filename).c_str(), attribs); ); auto removeReadonly = [&]() -> bool //may need to remove the readonly-attribute (e.g. on FAT usb drives) { if (attribs == INVALID_FILE_ATTRIBUTES) { const DWORD tmpAttr = ::GetFileAttributes(applyLongPathPrefix(filename).c_str()); if (tmpAttr == INVALID_FILE_ATTRIBUTES) throw FileError(replaceCpy(_("Cannot read file attributes of %x."), L"%x", fmtFileName(filename)) + L"\n\n" + getLastErrorFormatted()); if (tmpAttr & FILE_ATTRIBUTE_READONLY) { if (!::SetFileAttributes(applyLongPathPrefix(filename).c_str(), FILE_ATTRIBUTE_NORMAL)) throw FileError(replaceCpy(_("Cannot write file attributes of %x."), L"%x", fmtFileName(filename)) + L"\n\n" + getLastErrorFormatted()); attribs = tmpAttr; //reapplied on scope exit return true; } } return false; }; auto openFile = [&](bool conservativeApproach) { return ::CreateFile(applyLongPathPrefix(filename).c_str(), (conservativeApproach ? //some NAS seem to have issues with FILE_WRITE_ATTRIBUTES, even worse, they may fail silently! //http://sourceforge.net/tracker/?func=detail&atid=1093081&aid=3536680&group_id=234430 //Citrix shares seem to have this issue, too, but at least fail with "access denied" => try generic access first: GENERIC_READ | GENERIC_WRITE : //avoids mysterious "access denied" when using "GENERIC_READ | GENERIC_WRITE" on a read-only file, even *after* read-only was removed directly before the call! //http://sourceforge.net/tracker/?func=detail&atid=1093080&aid=3514569&group_id=234430 //since former gives an error notification we may very well try FILE_WRITE_ATTRIBUTES second. FILE_READ_ATTRIBUTES | FILE_WRITE_ATTRIBUTES), FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, nullptr, OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS | //needed to open a directory (procSl == SYMLINK_DIRECT ? FILE_FLAG_OPEN_REPARSE_POINT : 0), //process symlinks nullptr); }; HANDLE hFile = INVALID_HANDLE_VALUE; for (int i = 0; i < 2; ++i) //we will get this handle, no matter what! :) { //1. be conservative hFile = openFile(true); if (hFile == INVALID_HANDLE_VALUE) { if (::GetLastError() == ERROR_ACCESS_DENIED) //fails if file is read-only (or for "other" reasons) if (removeReadonly()) continue; //2. be a *little* fancy hFile = openFile(false); if (hFile == INVALID_HANDLE_VALUE) { if (::GetLastError() == ERROR_ACCESS_DENIED) if (removeReadonly()) continue; //3. after these herculean stunts we give up... throw FileError(replaceCpy(_("Cannot write modification time of %x."), L"%x", fmtFileName(filename)) + L"\n\n" + getLastErrorFormatted()); } } break; } ZEN_ON_SCOPE_EXIT(::CloseHandle(hFile)); auto isNullTime = [](const FILETIME& ft) { return ft.dwLowDateTime == 0 && ft.dwHighDateTime == 0; }; if (!::SetFileTime(hFile, //__in HANDLE hFile, !isNullTime(creationTime) ? &creationTime : nullptr, //__in_opt const FILETIME *lpCreationTime, nullptr, //__in_opt const FILETIME *lpLastAccessTime, &lastWriteTime)) //__in_opt const FILETIME *lpLastWriteTime { auto lastErr = ::GetLastError(); //function may fail if file is read-only: https://sourceforge.net/tracker/?func=detail&atid=1093080&aid=3514569&group_id=234430 if (lastErr == ERROR_ACCESS_DENIED) { //dynamically load windows API function: available with Windows Vista and later typedef BOOL (WINAPI* SetFileInformationByHandleFunc)(HANDLE hFile, FILE_INFO_BY_HANDLE_CLASS FileInformationClass, LPVOID lpFileInformation, DWORD dwBufferSize); const SysDllFun setFileInformationByHandle(L"kernel32.dll", "SetFileInformationByHandle"); if (setFileInformationByHandle) //if not: let the original error propagate! { auto setFileInfo = [&](FILE_BASIC_INFO basicInfo) //throw FileError; no const& since SetFileInformationByHandle() requires non-const parameter! { if (!setFileInformationByHandle(hFile, //__in HANDLE hFile, FileBasicInfo, //__in FILE_INFO_BY_HANDLE_CLASS FileInformationClass, &basicInfo, //__in LPVOID lpFileInformation, sizeof(basicInfo))) //__in DWORD dwBufferSize throw FileError(replaceCpy(_("Cannot write file attributes of %x."), L"%x", fmtFileName(filename)) + L"\n\n" + getLastErrorFormatted()); }; auto toLargeInteger = [](const FILETIME& ft) -> LARGE_INTEGER { LARGE_INTEGER tmp = {}; tmp.LowPart = ft.dwLowDateTime; tmp.HighPart = ft.dwHighDateTime; return tmp; }; //--------------------------------------------------------------------------- BY_HANDLE_FILE_INFORMATION fileInfo = {}; if (::GetFileInformationByHandle(hFile, &fileInfo)) if (fileInfo.dwFileAttributes & FILE_ATTRIBUTE_READONLY) { FILE_BASIC_INFO basicInfo = {}; //undocumented: file times of "0" stand for "don't change" basicInfo.FileAttributes = FILE_ATTRIBUTE_NORMAL; //[!] the bug in the ticket above requires we set this together with file times!!! basicInfo.LastWriteTime = toLargeInteger(lastWriteTime); // if (!isNullTime(creationTime)) basicInfo.CreationTime = toLargeInteger(creationTime); //set file time + attributes setFileInfo(basicInfo); //throw FileError try //... to restore original file attributes { FILE_BASIC_INFO basicInfo2 = {}; basicInfo2.FileAttributes = fileInfo.dwFileAttributes; setFileInfo(basicInfo2); //throw FileError } catch (FileError&) {} lastErr = ERROR_SUCCESS; } } } std::wstring errorMsg = replaceCpy(_("Cannot write modification time of %x."), L"%x", fmtFileName(filename)) + L"\n\n" + getLastErrorFormatted(lastErr); //add more meaningful message: FAT accepts only a subset of the NTFS date range if (lastErr == ERROR_INVALID_PARAMETER && dst::isFatDrive(filename)) { //we need a low-level reliable routine to format a potentially invalid date => don't use strftime!!! auto fmtDate = [](const FILETIME& ft) -> Zstring { SYSTEMTIME st = {}; if (!::FileTimeToSystemTime(&ft, //__in const FILETIME *lpFileTime, &st)) //__out LPSYSTEMTIME lpSystemTime return Zstring(); Zstring dateTime; { const int bufferSize = ::GetDateFormat(LOCALE_USER_DEFAULT, 0, &st, nullptr, nullptr, 0); if (bufferSize > 0) { std::vector buffer(bufferSize); if (::GetDateFormat(LOCALE_USER_DEFAULT, //_In_ LCID Locale, 0, //_In_ DWORD dwFlags, &st, //_In_opt_ const SYSTEMTIME *lpDate, nullptr, //_In_opt_ LPCTSTR lpFormat, &buffer[0], //_Out_opt_ LPTSTR lpDateStr, bufferSize) > 0) //_In_ int cchDate dateTime = &buffer[0]; //GetDateFormat() returns char count *including* 0-termination! } } const int bufferSize = ::GetTimeFormat(LOCALE_USER_DEFAULT, 0, &st, nullptr, nullptr, 0); if (bufferSize > 0) { std::vector buffer(bufferSize); if (::GetTimeFormat(LOCALE_USER_DEFAULT, 0, &st, nullptr, &buffer[0], bufferSize) > 0) { dateTime += L" "; dateTime += &buffer[0]; //GetDateFormat() returns char count *including* 0-termination! } } return dateTime; }; errorMsg += std::wstring(L"\nA FAT volume can only store dates between 1980 and 2107:\n") + L"\twrite (UTC): \t" + fmtDate(lastWriteTime) + (!isNullTime(creationTime) ? L"\n\tcreate (UTC): \t" + fmtDate(creationTime) : L""); } if (lastErr != ERROR_SUCCESS) throw FileError(errorMsg); } } #ifndef NDEBUG //dst hack: verify data written if (dst::isFatDrive(filename) && !dirExists(filename)) //throw() { FILETIME creationTimeDbg = {}; FILETIME lastWriteTimeDbg = {}; HANDLE hFile = ::CreateFile(applyLongPathPrefix(filename).c_str(), FILE_READ_ATTRIBUTES | FILE_WRITE_ATTRIBUTES, FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, nullptr, OPEN_EXISTING, 0, nullptr); assert(hFile != INVALID_HANDLE_VALUE); ZEN_ON_SCOPE_EXIT(::CloseHandle(hFile)); assert(::GetFileTime(hFile, //probably more up to date than GetFileAttributesEx()!? &creationTimeDbg, nullptr, &lastWriteTimeDbg)); assert(::CompareFileTime(&creationTimeDbg, &creationTime) == 0); assert(::CompareFileTime(&lastWriteTimeDbg, &lastWriteTime) == 0); } #endif #elif defined FFS_LINUX struct ::timespec newTimes[2] = {}; newTimes[0].tv_nsec = UTIME_OMIT; //omit access time newTimes[1].tv_sec = to(modTime); //modification time (seconds) if (::utimensat(AT_FDCWD, filename.c_str(), newTimes, procSl == SYMLINK_DIRECT ? AT_SYMLINK_NOFOLLOW : 0) != 0) throw FileError(replaceCpy(_("Cannot write modification time of %x."), L"%x", fmtFileName(filename)) + L"\n\n" + getLastErrorFormatted()); #elif defined FFS_MAC struct ::timeval newTimes[2] = {}; newTimes[0].tv_sec = ::time(nullptr); //access time (seconds) newTimes[1].tv_sec = to(modTime); //modification time (seconds) const int rv = procSl == SYMLINK_FOLLOW ? :: utimes(filename.c_str(), newTimes) : //utimensat() not yet implemented on OS X ::lutimes(filename.c_str(), newTimes); if (rv != 0) throw FileError(replaceCpy(_("Cannot write modification time of %x."), L"%x", fmtFileName(filename)) + L"\n\n" + getLastErrorFormatted()); #endif } bool zen::supportsPermissions(const Zstring& dirname) //throw FileError { #ifdef FFS_WIN const DWORD bufferSize = MAX_PATH + 1; std::vector buffer(bufferSize); if (!::GetVolumePathName(dirname.c_str(), //__in LPCTSTR lpszFileName, &buffer[0], //__out LPTSTR lpszVolumePathName, bufferSize)) //__in DWORD cchBufferLength throw FileError(replaceCpy(_("Cannot read file attributes of %x."), L"%x", fmtFileName(dirname)) + L"\n\n" + getLastErrorFormatted()); DWORD fsFlags = 0; if (!::GetVolumeInformation(&buffer[0], //__in_opt LPCTSTR lpRootPathName, nullptr, //__out LPTSTR lpVolumeNameBuffer, 0, //__in DWORD nVolumeNameSize, nullptr, //__out_opt LPDWORD lpVolumeSerialNumber, nullptr, //__out_opt LPDWORD lpMaximumComponentLength, &fsFlags, //__out_opt LPDWORD lpFileSystemFlags, nullptr, //__out LPTSTR lpFileSystemNameBuffer, 0)) //__in DWORD nFileSystemNameSize throw FileError(replaceCpy(_("Cannot read file attributes of %x."), L"%x", fmtFileName(dirname)) + L"\n\n" + getLastErrorFormatted()); return (fsFlags & FILE_PERSISTENT_ACLS) != 0; #elif defined FFS_LINUX || defined FFS_MAC return true; #endif } namespace { #ifdef FFS_WIN Zstring getSymlinkTargetPath(const Zstring& symlink) //throw FileError { //open handle to target of symbolic link const HANDLE hDir = ::CreateFile(applyLongPathPrefix(symlink).c_str(), 0, FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, nullptr, OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, //needed to open a directory nullptr); if (hDir == INVALID_HANDLE_VALUE) throw FileError(replaceCpy(_("Cannot resolve symbolic link %x."), L"%x", fmtFileName(symlink)) + L"\n\n" + getLastErrorFormatted()); ZEN_ON_SCOPE_EXIT(::CloseHandle(hDir)); //dynamically load windows API function typedef DWORD (WINAPI* GetFinalPathNameByHandleWFunc)(HANDLE hFile, LPTSTR lpszFilePath, DWORD cchFilePath, DWORD dwFlags); const SysDllFun getFinalPathNameByHandle(L"kernel32.dll", "GetFinalPathNameByHandleW"); if (!getFinalPathNameByHandle) throw FileError(replaceCpy(_("Cannot find system function %x."), L"%x", L"\"GetFinalPathNameByHandleW\"")); const DWORD BUFFER_SIZE = 10000; std::vector targetPath(BUFFER_SIZE); const DWORD charsWritten = getFinalPathNameByHandle(hDir, //__in HANDLE hFile, &targetPath[0], //__out LPTSTR lpszFilePath, BUFFER_SIZE, //__in DWORD cchFilePath, FILE_NAME_NORMALIZED); //__in DWORD dwFlags if (charsWritten >= BUFFER_SIZE || charsWritten == 0) { std::wstring errorMessage = replaceCpy(_("Cannot resolve symbolic link %x."), L"%x", fmtFileName(symlink)); if (charsWritten == 0) errorMessage += L"\n\n" + getLastErrorFormatted(); throw FileError(errorMessage); } return Zstring(&targetPath[0], charsWritten); } #endif #ifdef HAVE_SELINUX //copy SELinux security context void copySecurityContext(const Zstring& source, const Zstring& target, ProcSymlink procSl) //throw FileError { security_context_t contextSource = nullptr; const int rv = procSl == SYMLINK_FOLLOW ? ::getfilecon(source.c_str(), &contextSource) : ::lgetfilecon(source.c_str(), &contextSource); if (rv < 0) { if (errno == ENODATA || //no security context (allegedly) is not an error condition on SELinux errno == EOPNOTSUPP) //extended attributes are not supported by the filesystem return; throw FileError(replaceCpy(_("Cannot read security context of %x."), L"%x", fmtFileName(source)) + L"\n\n" + getLastErrorFormatted()); } ZEN_ON_SCOPE_EXIT(::freecon(contextSource)); { security_context_t contextTarget = nullptr; const int rv2 = procSl == SYMLINK_FOLLOW ? ::getfilecon(target.c_str(), &contextTarget) : ::lgetfilecon(target.c_str(), &contextTarget); if (rv2 < 0) { if (errno == EOPNOTSUPP) return; //else: still try to set security context } else { ZEN_ON_SCOPE_EXIT(::freecon(contextTarget)); if (::strcmp(contextSource, contextTarget) == 0) //nothing to do return; } } const int rv3 = procSl == SYMLINK_FOLLOW ? ::setfilecon(target.c_str(), contextSource) : ::lsetfilecon(target.c_str(), contextSource); if (rv3 < 0) throw FileError(replaceCpy(_("Cannot write security context of %x."), L"%x", fmtFileName(target)) + L"\n\n" + getLastErrorFormatted()); } #endif //HAVE_SELINUX //copy permissions for files, directories or symbolic links: requires admin rights void copyObjectPermissions(const Zstring& source, const Zstring& target, ProcSymlink procSl) //throw FileError { #ifdef FFS_WIN //in contrast to ::SetSecurityInfo(), ::SetFileSecurity() seems to honor the "inherit DACL/SACL" flags //CAVEAT: if a file system does not support ACLs, GetFileSecurity() will return successfully with a *valid* security descriptor containing *no* ACL entries! //NOTE: ::GetFileSecurity()/::SetFileSecurity() do NOT follow Symlinks! const Zstring sourceResolved = procSl == SYMLINK_FOLLOW && symlinkExists(source) ? getSymlinkTargetPath(source) : source; const Zstring targetResolved = procSl == SYMLINK_FOLLOW && symlinkExists(target) ? getSymlinkTargetPath(target) : target; //setting privileges requires admin rights! try { //enable privilege: required to read/write SACL information (only) activatePrivilege(SE_SECURITY_NAME); //throw FileError //Note: trying to copy SACL (SACL_SECURITY_INFORMATION) may return ERROR_PRIVILEGE_NOT_HELD (1314) on Samba shares. This is not due to missing privileges! //However, this is okay, since copying NTFS permissions doesn't make sense in this case anyway //enable privilege: required to copy owner information activatePrivilege(SE_RESTORE_NAME); //throw FileError //the following privilege may be required according to http://msdn.microsoft.com/en-us/library/aa364399(VS.85).aspx (although not needed nor active in my tests) activatePrivilege(SE_BACKUP_NAME); //throw FileError } catch (const FileError& e)//add some more context description (e.g. user is not an admin) { throw FileError(replaceCpy(_("Cannot read permissions of %x."), L"%x", fmtFileName(sourceResolved)) + L"\n\n" + e.toString()); } std::vector buffer(10000); //example of actually required buffer size: 192 bytes for (;;) { DWORD bytesNeeded = 0; if (::GetFileSecurity(applyLongPathPrefix(sourceResolved).c_str(), //__in LPCTSTR lpFileName, -> long path prefix IS needed, although it is NOT mentioned on MSDN!!! OWNER_SECURITY_INFORMATION | GROUP_SECURITY_INFORMATION | DACL_SECURITY_INFORMATION | SACL_SECURITY_INFORMATION, //__in SECURITY_INFORMATION RequestedInformation, reinterpret_cast(&buffer[0]), //__out_opt PSECURITY_DESCRIPTOR pSecurityDescriptor, static_cast(buffer.size()), //__in DWORD nLength, &bytesNeeded)) //__out LPDWORD lpnLengthNeeded break; //failure: ... if (bytesNeeded > buffer.size()) buffer.resize(bytesNeeded); else throw FileError(replaceCpy(_("Cannot read permissions of %x."), L"%x", fmtFileName(sourceResolved)) + L"\n\n" + getLastErrorFormatted()); } SECURITY_DESCRIPTOR& secDescr = reinterpret_cast(buffer[0]); /* SECURITY_DESCRIPTOR_CONTROL secCtrl = 0; { DWORD ctrlRev = 0; if (!::GetSecurityDescriptorControl(&secDescr, // __in PSECURITY_DESCRIPTOR pSecurityDescriptor, &secCtrl, // __out PSECURITY_DESCRIPTOR_CONTROL pControl, &ctrlRev)) //__out LPDWORD lpdwRevision throw FileErro } //interesting flags: //#define SE_DACL_PRESENT (0x0004) //#define SE_SACL_PRESENT (0x0010) //#define SE_DACL_PROTECTED (0x1000) //#define SE_SACL_PROTECTED (0x2000) */ if (!::SetFileSecurity(applyLongPathPrefix(targetResolved).c_str(), //__in LPCTSTR lpFileName, -> long path prefix IS needed, although it is NOT mentioned on MSDN!!! OWNER_SECURITY_INFORMATION | GROUP_SECURITY_INFORMATION | DACL_SECURITY_INFORMATION | SACL_SECURITY_INFORMATION, //__in SECURITY_INFORMATION SecurityInformation, &secDescr)) //__in PSECURITY_DESCRIPTOR pSecurityDescriptor throw FileError(replaceCpy(_("Cannot write permissions of %x."), L"%x", fmtFileName(targetResolved)) + L"\n\n" + getLastErrorFormatted()); /* PSECURITY_DESCRIPTOR buffer = nullptr; PSID owner = nullptr; PSID group = nullptr; PACL dacl = nullptr; PACL sacl = nullptr; //File Security and Access Rights: http://msdn.microsoft.com/en-us/library/aa364399(v=VS.85).aspx //SECURITY_INFORMATION Access Rights: http://msdn.microsoft.com/en-us/library/windows/desktop/aa379573(v=vs.85).aspx const HANDLE hSource = ::CreateFile(applyLongPathPrefix(source).c_str(), READ_CONTROL | ACCESS_SYSTEM_SECURITY, //ACCESS_SYSTEM_SECURITY required for SACL access FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, nullptr, OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS | (procSl == SYMLINK_DIRECT ? FILE_FLAG_OPEN_REPARSE_POINT : 0), //FILE_FLAG_BACKUP_SEMANTICS needed to open a directory nullptr); if (hSource == INVALID_HANDLE_VALUE) throw FileError ZEN_ON_SCOPE_EXIT(::CloseHandle(hSource)); // DWORD rc = ::GetNamedSecurityInfo(const_cast(applyLongPathPrefix(source).c_str()), -> does NOT dereference symlinks! DWORD rc = ::GetSecurityInfo(hSource, //__in LPTSTR pObjectName, SE_FILE_OBJECT, //__in SE_OBJECT_TYPE ObjectType, OWNER_SECURITY_INFORMATION | GROUP_SECURITY_INFORMATION | DACL_SECURITY_INFORMATION | SACL_SECURITY_INFORMATION, //__in SECURITY_INFORMATION SecurityInfo, &owner, //__out_opt PSID *ppsidOwner, &group, //__out_opt PSID *ppsidGroup, &dacl, //__out_opt PACL *ppDacl, &sacl, //__out_opt PACL *ppSacl, &buffer); //__out_opt PSECURITY_DESCRIPTOR *ppSecurityDescriptor if (rc != ERROR_SUCCESS) throw FileError ZEN_ON_SCOPE_EXIT(::LocalFree(buffer)); SECURITY_DESCRIPTOR_CONTROL secCtrl = 0; { DWORD ctrlRev = 0; if (!::GetSecurityDescriptorControl(buffer, // __in PSECURITY_DESCRIPTOR pSecurityDescriptor, &secCtrl, // __out PSECURITY_DESCRIPTOR_CONTROL pControl, &ctrlRev))//__out LPDWORD lpdwRevision throw FileError } //may need to remove the readonly-attribute FileUpdateHandle targetHandle(target, [=] { return ::CreateFile(applyLongPathPrefix(target).c_str(), // lpFileName GENERIC_WRITE | WRITE_OWNER | WRITE_DAC | ACCESS_SYSTEM_SECURITY, // dwDesiredAccess: all four seem to be required!!! FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, // dwShareMode nullptr, // lpSecurityAttributes OPEN_EXISTING, // dwCreationDisposition FILE_FLAG_BACKUP_SEMANTICS | (procSl == SYMLINK_DIRECT ? FILE_FLAG_OPEN_REPARSE_POINT : 0), // dwFlagsAndAttributes nullptr); // hTemplateFile }); if (targetHandle.get() == INVALID_HANDLE_VALUE) throw FileError SECURITY_INFORMATION secFlags = OWNER_SECURITY_INFORMATION | GROUP_SECURITY_INFORMATION | DACL_SECURITY_INFORMATION | SACL_SECURITY_INFORMATION; //SACL/DACL inheritence flag is NOT copied by default: we have to tell ::SetSecurityInfo(() to enable/disable it manually! //if (secCtrl & SE_DACL_PRESENT) secFlags |= (secCtrl & SE_DACL_PROTECTED) ? PROTECTED_DACL_SECURITY_INFORMATION : UNPROTECTED_DACL_SECURITY_INFORMATION; //if (secCtrl & SE_SACL_PRESENT) secFlags |= (secCtrl & SE_SACL_PROTECTED) ? PROTECTED_SACL_SECURITY_INFORMATION : UNPROTECTED_SACL_SECURITY_INFORMATION; // rc = ::SetNamedSecurityInfo(const_cast(applyLongPathPrefix(target).c_str()), //__in LPTSTR pObjectName, -> does NOT dereference symlinks! rc = ::SetSecurityInfo(targetHandle.get(), //__in LPTSTR pObjectName, SE_FILE_OBJECT, //__in SE_OBJECT_TYPE ObjectType, secFlags, //__in SECURITY_INFORMATION SecurityInfo, owner, //__in_opt PSID psidOwner, group, //__in_opt PSID psidGroup, dacl, //__in_opt PACL pDacl, sacl); //__in_opt PACL pSacl if (rc != ERROR_SUCCESS) throw FileError */ #elif defined FFS_LINUX || defined FFS_MAC #ifdef HAVE_SELINUX //copy SELinux security context copySecurityContext(source, target, procSl); //throw FileError #endif struct stat fileInfo = {}; if (procSl == SYMLINK_FOLLOW) { if (::stat(source.c_str(), &fileInfo) != 0) throw FileError(replaceCpy(_("Cannot read permissions of %x."), L"%x", fmtFileName(source)) + L"\n\n" + getLastErrorFormatted()); if (::chown(target.c_str(), fileInfo.st_uid, fileInfo.st_gid) != 0 || // may require admin rights! ::chmod(target.c_str(), fileInfo.st_mode) != 0) throw FileError(replaceCpy(_("Cannot write permissions of %x."), L"%x", fmtFileName(target)) + L"\n\n" + getLastErrorFormatted()); } else { if (::lstat(source.c_str(), &fileInfo) != 0) throw FileError(replaceCpy(_("Cannot read permissions of %x."), L"%x", fmtFileName(source)) + L"\n\n" + getLastErrorFormatted()); if (::lchown(target.c_str(), fileInfo.st_uid, fileInfo.st_gid) != 0 || // may require admin rights! (!symlinkExists(target) && ::chmod(target.c_str(), fileInfo.st_mode) != 0)) //setting access permissions doesn't make sense for symlinks on Linux: there is no lchmod() throw FileError(replaceCpy(_("Cannot write permissions of %x."), L"%x", fmtFileName(target)) + L"\n\n" + getLastErrorFormatted()); } #endif } void makeDirectoryRecursively(const Zstring& directory) //FileError, ErrorTargetExisting { assert(!endsWith(directory, FILE_NAME_SEPARATOR)); //even "C:\" should be "C:" as input! try { makeDirectoryPlain(directory, Zstring(), false); //throw FileError, ErrorTargetExisting, ErrorTargetPathMissing } catch (const ErrorTargetPathMissing&) { //we need to create parent directories first const Zstring dirParent = beforeLast(directory, FILE_NAME_SEPARATOR); if (!dirParent.empty()) { //recurse... try { makeDirectoryRecursively(dirParent); //throw FileError, (ErrorTargetExisting) } catch (const ErrorTargetExisting& e) { throw FileError(e.toString()); } //yes it's pathological, but we do not want to emit ErrorTargetExisting when creating parent directories! //now try again... makeDirectoryPlain(directory, Zstring(), false); //throw FileError, ErrorTargetExisting, (ErrorTargetPathMissing) return; } throw; } } } void zen::makeDirectory(const Zstring& directory, bool failIfExists) //throw FileError, ErrorTargetExisting { //remove trailing separator (even for C:\ root directories) const Zstring dirFormatted = endsWith(directory, FILE_NAME_SEPARATOR) ? beforeLast(directory, FILE_NAME_SEPARATOR) : directory; try { makeDirectoryRecursively(dirFormatted); //FileError, ErrorTargetExisting } catch (const ErrorTargetExisting&) { //avoid any file system race-condition by *not* checking directory existence again here!!! if (failIfExists) throw; } catch (const FileError&) { if (dirExists(directory)) //a file system race-condition! { /* could there be situations where a directory/network path exists, but creation fails with error different than "ErrorTargetExisting"?? - creation of C:\ fails with ERROR_ACCESS_DENIED rather than ERROR_ALREADY_EXISTS */ assert(false); if (failIfExists) throw; //do NOT convert to ErrorTargetExisting: if "failIfExists", not getting a ErrorTargetExisting *atomically* is unexpected! } else throw; } } void zen::makeDirectoryPlain(const Zstring& directory, //throw FileError, ErrorTargetExisting, ErrorTargetPathMissing const Zstring& templateDir, bool copyFilePermissions) { #ifdef FFS_WIN //special handling for volume root: trying to create existing root directory results in ERROR_ACCESS_DENIED rather than ERROR_ALREADY_EXISTS! Zstring dirTmp = removeLongPathPrefix(endsWith(directory, FILE_NAME_SEPARATOR) ? beforeLast(directory, FILE_NAME_SEPARATOR) : directory); if (dirTmp.size() == 2 && std::iswalpha(dirTmp[0]) && dirTmp[1] == L':') { dirTmp += FILE_NAME_SEPARATOR; //we do not support "C:" to represent a relative path! const ErrorCode lastError = dirExists(dirTmp) ? ERROR_ALREADY_EXISTS : ERROR_PATH_NOT_FOUND; const std::wstring msg = replaceCpy(_("Cannot create directory %x."), L"%x", fmtFileName(dirTmp)) + L"\n\n" + getLastErrorFormatted(lastError); if (lastError == ERROR_ALREADY_EXISTS) throw ErrorTargetExisting(msg); throw FileError(msg); //[!] this is NOT a ErrorTargetPathMissing case! } //don't use ::CreateDirectoryEx: //- it may fail with "wrong parameter (error code 87)" when source is on mapped online storage //- automatically copies symbolic links if encountered: unfortunately it doesn't copy symlinks over network shares but silently creates empty folders instead (on XP)! //- it isn't able to copy most junctions because of missing permissions (although target path can be retrieved alternatively!) if (!::CreateDirectory(applyLongPathPrefixCreateDir(directory).c_str(), //__in LPCTSTR lpPathName, nullptr)) //__in_opt LPSECURITY_ATTRIBUTES lpSecurityAttributes { ErrorCode lastError = getLastError(); //handle issues with already existing short 8.3 file names on Windows if (lastError == ERROR_ALREADY_EXISTS) if (have8dot3NameClash(directory)) { Fix8Dot3NameClash dummy(directory); //throw FileError; move clashing object to the side //now try again... if (::CreateDirectory(applyLongPathPrefixCreateDir(directory).c_str(), nullptr)) lastError = ERROR_SUCCESS; else lastError = getLastError(); } if (lastError != ERROR_SUCCESS) { const std::wstring msg = replaceCpy(_("Cannot create directory %x."), L"%x", fmtFileName(directory)) + L"\n\n" + getLastErrorFormatted(lastError); if (lastError == ERROR_ALREADY_EXISTS) throw ErrorTargetExisting(msg); else if (lastError == ERROR_PATH_NOT_FOUND) throw ErrorTargetPathMissing(msg); throw FileError(msg); } } #elif defined FFS_LINUX || defined FFS_MAC if (::mkdir(directory.c_str(), 0755) != 0) //mode: drwxr-xr-x { const std::wstring msg = replaceCpy(_("Cannot create directory %x."), L"%x", fmtFileName(directory)) + L"\n\n" + getLastErrorFormatted(); const ErrorCode lastError = getLastError(); if (lastError == EEXIST) throw ErrorTargetExisting(msg); else if (lastError == ENOENT) throw ErrorTargetPathMissing(msg); throw FileError(msg); } #endif if (!templateDir.empty()) { #ifdef FFS_WIN //try to copy file attributes Zstring sourcePath; if (symlinkExists(templateDir)) try { //get target directory of symbolic link sourcePath = getSymlinkTargetPath(templateDir); //throw FileError } catch (FileError&) {} //dereferencing a symbolic link usually fails if it is located on network drive or client is XP: NOT really an error... else sourcePath = templateDir; //*try* to copy file attributes if (!sourcePath.empty()) { const DWORD sourceAttr = ::GetFileAttributes(applyLongPathPrefix(sourcePath).c_str()); if (sourceAttr != INVALID_FILE_ATTRIBUTES) { ::SetFileAttributes(applyLongPathPrefix(directory).c_str(), sourceAttr); //copy "read-only and system attributes": http://blogs.msdn.com/b/oldnewthing/archive/2003/09/30/55100.aspx const bool isCompressed = (sourceAttr & FILE_ATTRIBUTE_COMPRESSED) != 0; const bool isEncrypted = (sourceAttr & FILE_ATTRIBUTE_ENCRYPTED) != 0; if (isEncrypted) ::EncryptFile(directory.c_str()); //seems no long path is required (check passed!) if (isCompressed) { HANDLE hDir = ::CreateFile(applyLongPathPrefix(directory).c_str(), GENERIC_READ | GENERIC_WRITE, //read access required for FSCTL_SET_COMPRESSION FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, nullptr, OPEN_EXISTING, FILE_FLAG_BACKUP_SEMANTICS, nullptr); if (hDir != INVALID_HANDLE_VALUE) { ZEN_ON_SCOPE_EXIT(::CloseHandle(hDir)); USHORT cmpState = COMPRESSION_FORMAT_DEFAULT; DWORD bytesReturned = 0; ::DeviceIoControl(hDir, //handle to file or directory FSCTL_SET_COMPRESSION, //dwIoControlCode &cmpState, //input buffer sizeof(cmpState), //size of input buffer nullptr, //lpOutBuffer 0, //OutBufferSize &bytesReturned, //number of bytes returned nullptr); //OVERLAPPED structure } } } } #endif zen::ScopeGuard guardNewDir = zen::makeGuard([&] { try { removeDirectory(directory); } catch (...) {} }); //ensure cleanup: //enforce copying file permissions: it's advertized on GUI... if (copyFilePermissions) copyObjectPermissions(templateDir, directory, SYMLINK_FOLLOW); //throw FileError guardNewDir.dismiss(); //target has been created successfully! } } void zen::copySymlink(const Zstring& sourceLink, const Zstring& targetLink, bool copyFilePermissions) //throw FileError { const Zstring linkPath = getSymlinkRawTargetString(sourceLink); //accept broken symlinks; throw FileError #ifdef FFS_WIN const bool isDirLink = [&]() -> bool { const DWORD ret = ::GetFileAttributes(applyLongPathPrefix(sourceLink).c_str()); return ret != INVALID_FILE_ATTRIBUTES && (ret& FILE_ATTRIBUTE_DIRECTORY); }(); //dynamically load windows API function typedef BOOLEAN (WINAPI* CreateSymbolicLinkFunc)(LPCTSTR lpSymlinkFileName, LPCTSTR lpTargetFileName, DWORD dwFlags); const SysDllFun createSymbolicLink(L"kernel32.dll", "CreateSymbolicLinkW"); if (!createSymbolicLink) throw FileError(replaceCpy(_("Cannot find system function %x."), L"%x", L"\"CreateSymbolicLinkW\"")); if (!createSymbolicLink(targetLink.c_str(), //__in LPTSTR lpSymlinkFileName, - seems no long path prefix is required... linkPath.c_str(), //__in LPTSTR lpTargetFileName, (isDirLink ? SYMBOLIC_LINK_FLAG_DIRECTORY : 0))) //__in DWORD dwFlags #elif defined FFS_LINUX || defined FFS_MAC if (::symlink(linkPath.c_str(), targetLink.c_str()) != 0) #endif throw FileError(replaceCpy(replaceCpy(_("Cannot copy symbolic link %x to %y."), L"%x", L"\n" + fmtFileName(sourceLink)), L"%y", L"\n" + fmtFileName(targetLink)) + L"\n\n" + getLastErrorFormatted()); //allow only consistent objects to be created -> don't place before ::symlink, targetLink may already exist zen::ScopeGuard guardNewDir = zen::makeGuard([&] { try { #ifdef FFS_WIN if (isDirLink) removeDirectory(targetLink); else #endif removeFile(targetLink); } catch (...) {} }); //file times: essential for sync'ing a symlink: enforce this! (don't just try!) { const Int64 modTime = getFileTime(sourceLink, SYMLINK_DIRECT); //throw FileError setFileTime(targetLink, modTime, SYMLINK_DIRECT); //throw FileError } if (copyFilePermissions) copyObjectPermissions(sourceLink, targetLink, SYMLINK_DIRECT); //throw FileError guardNewDir.dismiss(); //target has been created successfully! } namespace { #ifdef FFS_WIN /* CopyFileEx() BackupRead() FileRead() -------------------------------------------- Attributes YES NO NO create time NO NO NO ADS YES YES NO Encrypted YES NO(silent fail!) NO Compressed NO NO NO Sparse NO YES NO Nonstandard FS YES UNKNOWN -> issues writing ADS to Samba, issues reading from NAS, error copying files having "blocked" state... ect. PERF - 6% faster Mark stream as compressed: FSCTL_SET_COMPRESSION - compatible with both BackupRead() and FileRead() Current support for combinations of NTFS extended attributes: source attr | tf normal | tf compressed | tf encrypted | handled by ============|================================================================== --- | --- -C- E-- copyFileWindowsDefault --S | --S -CS E-S copyFileWindowsSparse -C- | -C- -C- E-- copyFileWindowsDefault -CS | -CS -CS E-S copyFileWindowsSparse E-- | E-- E-- E-- copyFileWindowsDefault E-S | E-- (NOK) E-- (NOK) E-- (NOK) copyFileWindowsDefault -> may fail with ERROR_DISK_FULL!! tf := target folder E := encrypted C := compressed S := sparse NOK := current behavior is not optimal/OK yet. Note: - if target parent folder is compressed or encrypted, both attributes are added automatically during file creation! - "compressed" and "encrypted" are mutually exclusive: http://support.microsoft.com/kb/223093/en-us */ //due to issues on non-NTFS volumes, we should use the copy-as-sparse routine only if required and supported! bool canCopyAsSparse(DWORD fileAttrSource, const Zstring& targetFile) //throw () { const bool sourceIsEncrypted = (fileAttrSource & FILE_ATTRIBUTE_ENCRYPTED) != 0; const bool sourceIsSparse = (fileAttrSource & FILE_ATTRIBUTE_SPARSE_FILE) != 0; if (sourceIsEncrypted || !sourceIsSparse) //BackupRead() silently fails reading encrypted files! return false; //small perf optimization: don't check "targetFile" if not needed //------------------------------------------------------------------------------------ const DWORD bufferSize = 10000; std::vector buffer(bufferSize); //full pathName need not yet exist! if (!::GetVolumePathName(targetFile.c_str(), //__in LPCTSTR lpszFileName, &buffer[0], //__out LPTSTR lpszVolumePathName, bufferSize)) //__in DWORD cchBufferLength return false; DWORD fsFlagsTarget = 0; if (!::GetVolumeInformation(&buffer[0], //__in_opt LPCTSTR lpRootPathName nullptr, //__out_opt LPTSTR lpVolumeNameBuffer, 0, //__in DWORD nVolumeNameSize, nullptr, //__out_opt LPDWORD lpVolumeSerialNumber, nullptr, //__out_opt LPDWORD lpMaximumComponentLength, &fsFlagsTarget, //__out_opt LPDWORD lpFileSystemFlags, nullptr, //__out LPTSTR lpFileSystemNameBuffer, 0)) //__in DWORD nFileSystemNameSize return false; const bool targetSupportSparse = (fsFlagsTarget & FILE_SUPPORTS_SPARSE_FILES) != 0; return targetSupportSparse; //both source and target must not be FAT since copyFileWindowsSparse() does no DST hack! implicitly guaranteed at this point! } bool canCopyAsSparse(const Zstring& sourceFile, const Zstring& targetFile) //throw () { //follow symlinks! HANDLE hSource = ::CreateFile(applyLongPathPrefix(sourceFile).c_str(), 0, FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, //all shared modes are required to read files that are open in other applications nullptr, OPEN_EXISTING, 0, nullptr); if (hSource == INVALID_HANDLE_VALUE) return false; ZEN_ON_SCOPE_EXIT(::CloseHandle(hSource)); BY_HANDLE_FILE_INFORMATION fileInfoSource = {}; if (!::GetFileInformationByHandle(hSource, &fileInfoSource)) return false; return canCopyAsSparse(fileInfoSource.dwFileAttributes, targetFile); //throw () } //precondition: canCopyAsSparse() must return "true"! void copyFileWindowsSparse(const Zstring& sourceFile, const Zstring& targetFile, CallbackCopyFile* callback, FileAttrib* newAttrib) //throw FileError, ErrorTargetPathMissing, ErrorTargetExisting, ErrorFileLocked { assert(canCopyAsSparse(sourceFile, targetFile)); //try to get backup read and write privileges: who knows, maybe this helps solve some obscure "access denied" errors try { activatePrivilege(SE_BACKUP_NAME); } catch (const FileError&) {} try { activatePrivilege(SE_RESTORE_NAME); } catch (const FileError&) {} //open sourceFile for reading HANDLE hFileSource = ::CreateFile(applyLongPathPrefix(sourceFile).c_str(), GENERIC_READ, FILE_SHARE_READ | FILE_SHARE_DELETE, nullptr, OPEN_EXISTING, //FILE_FLAG_OVERLAPPED must not be used! FILE_FLAG_SEQUENTIAL_SCAN | FILE_FLAG_BACKUP_SEMANTICS, //FILE_FLAG_NO_BUFFERING should not be used! nullptr); if (hFileSource == INVALID_HANDLE_VALUE) { const DWORD lastError = ::GetLastError(); const std::wstring shortMsg = replaceCpy(_("Cannot read file %x."), L"%x", fmtFileName(sourceFile)); //if file is locked throw "ErrorFileLocked" instead! if (lastError == ERROR_SHARING_VIOLATION || lastError == ERROR_LOCK_VIOLATION) { const Zstring procList = getLockingProcessNames(sourceFile); //throw() throw ErrorFileLocked(shortMsg + L"\n\n" + (!procList.empty() ? _("The file is locked by another process:") + L"\n" + procList : getLastErrorFormatted(lastError))); } throw FileError(shortMsg + L"\n\n" + getLastErrorFormatted(lastError) + L" (open)"); } ZEN_ON_SCOPE_EXIT(::CloseHandle(hFileSource)); //---------------------------------------------------------------------- BY_HANDLE_FILE_INFORMATION fileInfoSource = {}; if (!::GetFileInformationByHandle(hFileSource, &fileInfoSource)) throw FileError(replaceCpy(_("Cannot read file attributes of %x."), L"%x", fmtFileName(sourceFile)) + L"\n\n" + getLastErrorFormatted()); //---------------------------------------------------------------------- const DWORD validAttribs = FILE_ATTRIBUTE_NORMAL | //"This attribute is valid only if used alone." FILE_ATTRIBUTE_READONLY | FILE_ATTRIBUTE_HIDDEN | FILE_ATTRIBUTE_SYSTEM | FILE_ATTRIBUTE_ARCHIVE | //those two are not set properly (not worse than ::CopyFileEx()) FILE_ATTRIBUTE_NOT_CONTENT_INDEXED; // //FILE_ATTRIBUTE_ENCRYPTED -> no! //create targetFile and open it for writing HANDLE hFileTarget = ::CreateFile(applyLongPathPrefix(targetFile).c_str(), GENERIC_READ | GENERIC_WRITE, //read access required for FSCTL_SET_COMPRESSION FILE_SHARE_DELETE, //FILE_SHARE_DELETE is required to rename file while handle is open! nullptr, CREATE_NEW, FILE_FLAG_SEQUENTIAL_SCAN | FILE_FLAG_BACKUP_SEMANTICS | (fileInfoSource.dwFileAttributes & validAttribs), //FILE_FLAG_OVERLAPPED must not be used! FILE_FLAG_NO_BUFFERING should not be used! nullptr); if (hFileTarget == INVALID_HANDLE_VALUE) { const DWORD lastError = ::GetLastError(); const std::wstring errorMessage = replaceCpy(_("Cannot write file %x."), L"%x", fmtFileName(targetFile)) + L"\n\n" + getLastErrorFormatted(lastError) + L" (open)"; if (lastError == ERROR_FILE_EXISTS || //confirmed to be used lastError == ERROR_ALREADY_EXISTS) //comment on msdn claims, this one is used on Windows Mobile 6 throw ErrorTargetExisting(errorMessage); if (lastError == ERROR_PATH_NOT_FOUND) throw ErrorTargetPathMissing(errorMessage); throw FileError(errorMessage); } ScopeGuard guardTarget = makeGuard([&] { try { removeFile(targetFile); } catch (...) {} }); //transactional behavior: guard just after opening target and before managing hFileOut ZEN_ON_SCOPE_EXIT(::CloseHandle(hFileTarget)); //---------------------------------------------------------------------- BY_HANDLE_FILE_INFORMATION fileInfoTarget = {}; if (!::GetFileInformationByHandle(hFileTarget, &fileInfoTarget)) throw FileError(replaceCpy(_("Cannot read file attributes of %x."), L"%x", fmtFileName(targetFile)) + L"\n\n" + getLastErrorFormatted()); //return up-to-date file attributes if (newAttrib) { newAttrib->fileSize = UInt64(fileInfoSource.nFileSizeLow, fileInfoSource.nFileSizeHigh); newAttrib->modificationTime = toTimeT(fileInfoSource.ftLastWriteTime); //no DST hack (yet) newAttrib->sourceFileId = extractFileID(fileInfoSource); newAttrib->targetFileId = extractFileID(fileInfoTarget); } //#################### copy NTFS compressed attribute ######################### const bool sourceIsCompressed = (fileInfoSource.dwFileAttributes & FILE_ATTRIBUTE_COMPRESSED) != 0; const bool targetIsCompressed = (fileInfoTarget.dwFileAttributes & FILE_ATTRIBUTE_COMPRESSED) != 0; //already set by CreateFile if target parent folder is compressed! if (sourceIsCompressed && !targetIsCompressed) { USHORT cmpState = COMPRESSION_FORMAT_DEFAULT; DWORD bytesReturned = 0; if (!::DeviceIoControl(hFileTarget, //handle to file or directory FSCTL_SET_COMPRESSION, //dwIoControlCode &cmpState, //input buffer sizeof(cmpState), //size of input buffer nullptr, //lpOutBuffer 0, //OutBufferSize &bytesReturned, //number of bytes returned nullptr)) //OVERLAPPED structure {} //may legitimately fail with ERROR_INVALID_FUNCTION if: // - target folder is encrypted // - target volume does not support compressed attribute -> unlikely in this context } //############################################################################# //although it seems the sparse attribute is set automatically by BackupWrite, we are required to do this manually: http://support.microsoft.com/kb/271398/en-us //Quote: It is the responsibility of the backup utility to apply file attributes to a file after it is restored by using BackupWrite. //The application should retrieve the attributes by using GetFileAttributes prior to creating a backup with BackupRead. //If a file originally had the sparse attribute (FILE_ATTRIBUTE_SPARSE_FILE), the backup utility must explicitly set the //attribute on the restored file. //if (sourceIsSparse && targetSupportsSparse) -> no need to check, this is our precondition! { DWORD bytesReturned = 0; if (!::DeviceIoControl(hFileTarget, //handle to file FSCTL_SET_SPARSE, //dwIoControlCode nullptr, //input buffer 0, //size of input buffer nullptr, //lpOutBuffer 0, //OutBufferSize &bytesReturned, //number of bytes returned nullptr)) //OVERLAPPED structure throw FileError(replaceCpy(_("Cannot write file attributes of %x."), L"%x", fmtFileName(targetFile)) + L"\n\n" + zen::getLastErrorFormatted() + L" (NTFS sparse)"); } //---------------------------------------------------------------------- const DWORD BUFFER_SIZE = 128 * 1024; //must be greater than sizeof(WIN32_STREAM_ID) std::vector buffer(BUFFER_SIZE); LPVOID contextRead = nullptr; //manage context for BackupRead()/BackupWrite() LPVOID contextWrite = nullptr; // ZEN_ON_SCOPE_EXIT( if (contextRead ) ::BackupRead (0, nullptr, 0, nullptr, true, false, &contextRead); //lpContext must be passed [...] all other parameters are ignored. if (contextWrite) ::BackupWrite(0, nullptr, 0, nullptr, true, false, &contextWrite); ); //stream-copy sourceFile to targetFile bool eof = false; bool someBytesWritten = false; //try to detect failure reading encrypted files do { DWORD bytesRead = 0; if (!::BackupRead(hFileSource, //__in HANDLE hFile, &buffer[0], //__out LPBYTE lpBuffer, BUFFER_SIZE, //__in DWORD nNumberOfBytesToRead, &bytesRead, //__out LPDWORD lpNumberOfBytesRead, false, //__in BOOL bAbort, false, //__in BOOL bProcessSecurity, &contextRead)) //__out LPVOID *lpContext throw FileError(replaceCpy(_("Cannot read file %x."), L"%x", fmtFileName(sourceFile)) + L"\n\n" + getLastErrorFormatted()); //better use fine-granular error messages "reading/writing"! if (bytesRead > BUFFER_SIZE) throw FileError(replaceCpy(_("Cannot read file %x."), L"%x", fmtFileName(sourceFile)) + L"\n\n" + L"(buffer overflow)"); if (bytesRead < BUFFER_SIZE) eof = true; DWORD bytesWritten = 0; if (!::BackupWrite(hFileTarget, //__in HANDLE hFile, &buffer[0], //__in LPBYTE lpBuffer, bytesRead, //__in DWORD nNumberOfBytesToWrite, &bytesWritten, //__out LPDWORD lpNumberOfBytesWritten, false, //__in BOOL bAbort, false, //__in BOOL bProcessSecurity, &contextWrite)) //__out LPVOID *lpContext throw FileError(replaceCpy(_("Cannot write file %x."), L"%x", fmtFileName(targetFile)) + L"\n\n" + getLastErrorFormatted()); if (bytesWritten != bytesRead) throw FileError(replaceCpy(_("Cannot write file %x."), L"%x", fmtFileName(targetFile)) + L"\n\n" + L"(incomplete write)"); //total bytes transferred may be larger than file size! context information + ADS or smaller (sparse, compressed)! //invoke callback method to update progress indicators if (callback) callback->updateCopyStatus(Int64(bytesRead)); //throw X! if (bytesRead > 0) someBytesWritten = true; } while (!eof); //DST hack not required, since both source and target volumes cannot be FAT! //::BackupRead() silently fails reading encrypted files -> double check! if (!someBytesWritten && UInt64(fileInfoSource.nFileSizeLow, fileInfoSource.nFileSizeHigh) != 0U) //note: there is no guaranteed ordering relation beween bytes transferred and file size! Consider ADS (>) and compressed/sparse files (<)! throw FileError(replaceCpy(_("Cannot read file %x."), L"%x", fmtFileName(sourceFile)) + L"\n\n" + L"(unknown error)"); //time needs to be set at the end: BackupWrite() changes modification time if (!::SetFileTime(hFileTarget, &fileInfoSource.ftCreationTime, nullptr, &fileInfoSource.ftLastWriteTime)) throw FileError(replaceCpy(_("Cannot write modification time of %x."), L"%x", fmtFileName(targetFile)) + L"\n\n" + getLastErrorFormatted()); guardTarget.dismiss(); /* //create sparse file for testing: HANDLE hSparse = ::CreateFile(L"C:\\sparse.file", GENERIC_READ | GENERIC_WRITE, //read access required for FSCTL_SET_COMPRESSION FILE_SHARE_READ | FILE_SHARE_WRITE | FILE_SHARE_DELETE, nullptr, CREATE_NEW, FILE_FLAG_SEQUENTIAL_SCAN, nullptr); if (hFileTarget == INVALID_HANDLE_VALUE) throw 1; ZEN_ON_SCOPE_EXIT(::CloseHandle(hSparse)); DWORD br = 0; if (!::DeviceIoControl(hSparse, FSCTL_SET_SPARSE, nullptr, 0, nullptr, 0, &br,nullptr)) throw 1; LARGE_INTEGER liDistanceToMove = {}; liDistanceToMove.QuadPart = 1024 * 1024 * 1024; //create 5 TB sparse file liDistanceToMove.QuadPart *= 5 * 1024; //maximum file size on NTFS: 16 TB - 64 kB if (!::SetFilePointerEx(hSparse, liDistanceToMove, nullptr, FILE_BEGIN)) throw 1; if (!SetEndOfFile(hSparse)) throw 1; FILE_ZERO_DATA_INFORMATION zeroInfo = {}; zeroInfo.BeyondFinalZero.QuadPart = liDistanceToMove.QuadPart; if (!::DeviceIoControl(hSparse, FSCTL_SET_ZERO_DATA, &zeroInfo, sizeof(zeroInfo), nullptr, 0, &br, nullptr)) throw 1; */ } DEFINE_NEW_FILE_ERROR(ErrorShouldCopyAsSparse); class ErrorHandling { public: ErrorHandling() : shouldCopyAsSparse(false), exceptionInUserCallback(nullptr) {} //call context: copyCallbackInternal() void reportErrorShouldCopyAsSparse() { shouldCopyAsSparse = true; } void reportUserException(CallbackCopyFile& userCallback) { exceptionInUserCallback = &userCallback; } void reportError(const std::wstring& message) { errorMsg = message; } //call context: copyFileWindowsDefault() void evaluateErrors() //throw X { if (shouldCopyAsSparse) throw ErrorShouldCopyAsSparse(L"sparse dummy value"); if (exceptionInUserCallback) exceptionInUserCallback->updateCopyStatus(0); //rethrow (hopefully!) if (!errorMsg.empty()) throw FileError(errorMsg); } private: bool shouldCopyAsSparse; // std::wstring errorMsg; //these are exclusive! CallbackCopyFile* exceptionInUserCallback; // }; struct CallbackData { CallbackData(CallbackCopyFile* cb, //may be nullptr const Zstring& sourceFile, const Zstring& targetFile) : sourceFile_(sourceFile), targetFile_(targetFile), userCallback(cb) {} const Zstring& sourceFile_; const Zstring& targetFile_; CallbackCopyFile* const userCallback; //optional! ErrorHandling errorHandler; FileAttrib newAttrib; //modified by CopyFileEx() at beginning Int64 bytesReported; //used internally to calculate bytes transferred delta }; DWORD CALLBACK copyCallbackInternal(LARGE_INTEGER totalFileSize, LARGE_INTEGER totalBytesTransferred, LARGE_INTEGER streamSize, LARGE_INTEGER streamBytesTransferred, DWORD dwStreamNumber, DWORD dwCallbackReason, HANDLE hSourceFile, HANDLE hDestinationFile, LPVOID lpData) { /* this callback is invoked for block sizes managed by Windows, these may vary from e.g. 64 kB up to 1MB. It seems this depends on file size amongst others. symlink handling: if source is a symlink and COPY_FILE_COPY_SYMLINK is specified, this callback is NOT invoked! if source is a symlink and COPY_FILE_COPY_SYMLINK is NOT specified, this callback is called and hSourceFile is a handle to the *target* of the link! file time handling: ::CopyFileEx() will copy file modification time (only) over from source file AFTER the last invokation of this callback => it is possible to adapt file creation time of target in here, but NOT file modification time! CAVEAT: if ::CopyFileEx() fails to set modification time, it silently ignores this error and returns success!!! see procmon log in: https://sourceforge.net/tracker/?func=detail&atid=1093080&aid=3514569&group_id=234430 alternate data stream handling: CopyFileEx() processes multiple streams one after another, stream 1 is the file data stream and always available! Each stream is initialized with CALLBACK_STREAM_SWITCH and provides *new* hSourceFile, hDestinationFile. Calling GetFileInformationByHandle() on hDestinationFile for stream > 1 results in ERROR_ACCESS_DENIED! totalBytesTransferred contains size of *all* streams and so can be larger than the "file size" file attribute */ CallbackData& cbd = *static_cast(lpData); if (dwCallbackReason == CALLBACK_STREAM_SWITCH && //called up-front for every file (even if 0-sized) dwStreamNumber == 1) //consider ADS! { //#################### return source file attributes ################################ BY_HANDLE_FILE_INFORMATION fileInfoSrc = {}; if (!::GetFileInformationByHandle(hSourceFile, &fileInfoSrc)) { cbd.errorHandler.reportError(replaceCpy(_("Cannot read file attributes of %x."), L"%x", fmtFileName(cbd.sourceFile_)) + L"\n\n" + getLastErrorFormatted()); return PROGRESS_CANCEL; } BY_HANDLE_FILE_INFORMATION fileInfoTrg = {}; if (!::GetFileInformationByHandle(hDestinationFile, &fileInfoTrg)) { cbd.errorHandler.reportError(replaceCpy(_("Cannot read file attributes of %x."), L"%x", fmtFileName(cbd.targetFile_)) + L"\n\n" + getLastErrorFormatted()); return PROGRESS_CANCEL; } cbd.newAttrib.fileSize = UInt64(fileInfoSrc.nFileSizeLow, fileInfoSrc.nFileSizeHigh); cbd.newAttrib.modificationTime = toTimeT(fileInfoSrc.ftLastWriteTime); //no DST hack (yet) cbd.newAttrib.sourceFileId = extractFileID(fileInfoSrc); cbd.newAttrib.targetFileId = extractFileID(fileInfoTrg); //#################### switch to sparse file copy if req. ####################### if (canCopyAsSparse(fileInfoSrc.dwFileAttributes, cbd.targetFile_)) //throw () { cbd.errorHandler.reportErrorShouldCopyAsSparse(); //use a different copy routine! return PROGRESS_CANCEL; } //#################### copy file creation time ################################ ::SetFileTime(hDestinationFile, &fileInfoSrc.ftCreationTime, nullptr, nullptr); //no error handling! //#################### copy NTFS compressed attribute ######################### const bool sourceIsCompressed = (fileInfoSrc.dwFileAttributes & FILE_ATTRIBUTE_COMPRESSED) != 0; const bool targetIsCompressed = (fileInfoTrg.dwFileAttributes & FILE_ATTRIBUTE_COMPRESSED) != 0; //already set by CopyFileEx if target parent folder is compressed! if (sourceIsCompressed && !targetIsCompressed) { USHORT cmpState = COMPRESSION_FORMAT_DEFAULT; DWORD bytesReturned = 0; if (!::DeviceIoControl(hDestinationFile, //handle to file or directory FSCTL_SET_COMPRESSION, //dwIoControlCode &cmpState, //input buffer sizeof(cmpState), //size of input buffer nullptr, //lpOutBuffer 0, //OutBufferSize &bytesReturned, //number of bytes returned nullptr)) //OVERLAPPED structure {} //may legitimately fail with ERROR_INVALID_FUNCTION if // - if target folder is encrypted // - target volume does not support compressed attribute //############################################################################# } } //called after copy operation is finished - note: for 0-sized files this callback is invoked just ONCE! //if (totalFileSize.QuadPart == totalBytesTransferred.QuadPart && dwStreamNumber == 1) {} if (cbd.userCallback && totalBytesTransferred.QuadPart >= 0) //should be always true, but let's still check try { cbd.userCallback->updateCopyStatus(totalBytesTransferred.QuadPart - cbd.bytesReported); //throw X! cbd.bytesReported = totalBytesTransferred.QuadPart; } catch (...) { //#warning migrate to std::exception_ptr when available cbd.errorHandler.reportUserException(*cbd.userCallback); return PROGRESS_CANCEL; } return PROGRESS_CONTINUE; } const bool supportNonEncryptedDestination = winXpOrLater(); //encrypted destination is not supported with Windows 2000 //const bool supportUnbufferedCopy = vistaOrLater(); //caveat: function scope static initialization is not thread-safe in VS 2010! void copyFileWindowsDefault(const Zstring& sourceFile, const Zstring& targetFile, CallbackCopyFile* callback, FileAttrib* newAttrib) //throw FileError, ErrorTargetPathMissing, ErrorTargetExisting, ErrorFileLocked, ErrorShouldCopyAsSparse { //try to get backup read and write privileges: who knows, maybe this helps solve some obscure "access denied" errors try { activatePrivilege(SE_BACKUP_NAME); } catch (const FileError&) {} try { activatePrivilege(SE_RESTORE_NAME); } catch (const FileError&) {} zen::ScopeGuard guardTarget = zen::makeGuard([&] { try { removeFile(targetFile); } catch (...) {} }); //transactional behavior: guard just before starting copy, we don't trust ::CopyFileEx(), do we? ;) DWORD copyFlags = COPY_FILE_FAIL_IF_EXISTS; if (supportNonEncryptedDestination) copyFlags |= COPY_FILE_ALLOW_DECRYPTED_DESTINATION; //allow copying from encrypted to non-encrytped location //if (supportUnbufferedCopy) //see http://blogs.technet.com/b/askperf/archive/2007/05/08/slow-large-file-copy-issues.aspx // copyFlags |= COPY_FILE_NO_BUFFERING; //no perf difference at worst, huge improvement for large files (20% in test NTFS -> NTFS) //It's a shame this flag causes file corruption! https://sourceforge.net/projects/freefilesync/forums/forum/847542/topic/5177950 //documentation on CopyFile2() even states: "It is not recommended to pause copies that are using this flag." How dangerous is this thing, why offer it at all??? //perf advantage: ~15% faster CallbackData cbd(callback, sourceFile, targetFile); const bool success = ::CopyFileEx( //same performance like CopyFile() applyLongPathPrefix(sourceFile).c_str(), //__in LPCTSTR lpExistingFileName, applyLongPathPrefix(targetFile).c_str(), //__in LPCTSTR lpNewFileName, copyCallbackInternal, //__in_opt LPPROGRESS_ROUTINE lpProgressRoutine, &cbd, //__in_opt LPVOID lpData, nullptr, //__in_opt LPBOOL pbCancel, copyFlags) != FALSE; //__in DWORD dwCopyFlags cbd.errorHandler.evaluateErrors(); //throw ?, process errors in callback first! if (!success) { const DWORD lastError = ::GetLastError(); //don't suppress "lastError == ERROR_REQUEST_ABORTED": a user aborted operation IS an error condition! //trying to copy huge sparse files may directly fail with ERROR_DISK_FULL before entering the callback function if (canCopyAsSparse(sourceFile, targetFile)) //throw () throw ErrorShouldCopyAsSparse(L"sparse dummy value2"); //assemble error message... std::wstring errorMessage = replaceCpy(replaceCpy(_("Cannot copy file %x to %y."), L"%x", L"\n" + fmtFileName(sourceFile)), L"%y", L"\n" + fmtFileName(targetFile)) + L"\n\n" + getLastErrorFormatted(lastError); //if file is locked throw "ErrorFileLocked" instead! if (lastError == ERROR_SHARING_VIOLATION || lastError == ERROR_LOCK_VIOLATION) { const Zstring procList = getLockingProcessNames(sourceFile); //throw() -> enhance error message! throw ErrorFileLocked(replaceCpy(_("Cannot read file %x."), L"%x", fmtFileName(sourceFile)) + L"\n\n" + (!procList.empty() ? _("The file is locked by another process:") + L"\n" + procList : getLastErrorFormatted(lastError))); } //if target is existing this functions is expected to throw ErrorTargetExisting!!! if (lastError == ERROR_FILE_EXISTS || //confirmed to be used lastError == ERROR_ALREADY_EXISTS) //not sure if used -> better be safe than sorry!!! { guardTarget.dismiss(); //don't delete file that existed previously! throw ErrorTargetExisting(errorMessage); } if (lastError == ERROR_PATH_NOT_FOUND) { guardTarget.dismiss(); //not relevant throw ErrorTargetPathMissing(errorMessage); } try //add more meaningful message { //trying to copy > 4GB file to FAT/FAT32 volume gives obscure ERROR_INVALID_PARAMETER (FAT can indeed handle files up to 4 Gig, tested!) if (lastError == ERROR_INVALID_PARAMETER && dst::isFatDrive(targetFile) && getFilesize(sourceFile) >= 4U * UInt64(1024U * 1024 * 1024)) //throw FileError errorMessage += L"\nFAT volume cannot store files larger than 4 gigabyte!"; //note: ERROR_INVALID_PARAMETER can also occur when copying to a SharePoint server or MS SkyDrive and the target filename is of a restricted type. } catch (...) {} throw FileError(errorMessage); } if (newAttrib) *newAttrib = cbd.newAttrib; { //DST hack const Int64 modTime = getFileTime(sourceFile, SYMLINK_FOLLOW); //throw FileError setFileTime(targetFile, modTime, SYMLINK_FOLLOW); //throw FileError //caveat: - ::CopyFileEx() silently *ignores* failure to set modification time!!! => we need to set again in order to catch such errors! // - this sequence leads to a loss of precision of up to 1 sec! // - perf-loss on USB sticks with many small files of about 30%! damn! if (newAttrib) newAttrib->modificationTime = modTime; } guardTarget.dismiss(); //target has been created successfully! } //another layer to support copying sparse files inline void copyFileWindowsSelectRoutine(const Zstring& sourceFile, const Zstring& targetFile, CallbackCopyFile* callback, FileAttrib* sourceAttr) { try { copyFileWindowsDefault(sourceFile, targetFile, callback, sourceAttr); //throw ErrorShouldCopyAsSparse et al. } catch (ErrorShouldCopyAsSparse&) //we cheaply check for this condition within callback of ::CopyFileEx()! { copyFileWindowsSparse(sourceFile, targetFile, callback, sourceAttr); } } //another layer of indirection solving 8.3 name clashes inline void copyFileWindows(const Zstring& sourceFile, const Zstring& targetFile, CallbackCopyFile* callback, FileAttrib* sourceAttr) { try { copyFileWindowsSelectRoutine(sourceFile, targetFile, callback, sourceAttr); //throw FileError, ErrorTargetPathMissing, ErrorTargetExisting, ErrorFileLocked } catch (const ErrorTargetExisting&) { //try to handle issues with already existing short 8.3 file names on Windows if (have8dot3NameClash(targetFile)) { Fix8Dot3NameClash dummy(targetFile); //throw FileError; move clashing filename to the side copyFileWindowsSelectRoutine(sourceFile, targetFile, callback, sourceAttr); //throw FileError; the short filename name clash is solved, this should work now return; } throw; } } #elif defined FFS_LINUX || defined FFS_MAC void copyFileLinuxMac(const Zstring& sourceFile, const Zstring& targetFile, CallbackCopyFile* callback, FileAttrib* newAttrib) //throw FileError, ErrorTargetPathMissing, ErrorTargetExisting { //open sourceFile for reading FileInputUnbuffered fileIn(sourceFile); //throw FileError, ErrorNotExisting struct ::stat sourceInfo = {}; if (::fstat(fileIn.getDescriptor(), &sourceInfo) != 0) //read file attributes from source throw FileError(replaceCpy(_("Cannot read file attributes of %x."), L"%x", fmtFileName(sourceFile)) + L"\n\n" + getLastErrorFormatted()); zen::ScopeGuard guardTarget = zen::makeGuard([&] { try { removeFile(targetFile); } catch (...) {} }); //transactional behavior: place guard before lifetime of FileOutput try { //create targetFile and open it for writing FileOutputUnbuffered fileOut(targetFile, sourceInfo.st_mode); //throw FileError, ErrorTargetPathMissing, ErrorTargetExisting //copy contents of sourceFile to targetFile std::vector buffer(128 * 1024); //see comment in FileInputUnbuffered::read do { const size_t bytesRead = fileIn.read(&buffer[0], buffer.size()); //throw FileError fileOut.write(&buffer[0], bytesRead); //throw FileError //invoke callback method to update progress indicators if (callback) callback->updateCopyStatus(Int64(bytesRead)); //throw X! } while (!fileIn.eof()); //adapt target file modification time: { //read and return file statistics struct ::stat targetInfo = {}; if (::fstat(fileOut.getDescriptor(), &targetInfo) != 0) throw FileError(replaceCpy(_("Cannot read file attributes of %x."), L"%x", fmtFileName(targetFile)) + L"\n\n" + getLastErrorFormatted()); if (newAttrib) { newAttrib->fileSize = UInt64(sourceInfo.st_size); newAttrib->modificationTime = sourceInfo.st_mtime; newAttrib->sourceFileId = extractFileID(sourceInfo); newAttrib->targetFileId = extractFileID(targetInfo); } } } catch (const ErrorTargetExisting&) { guardTarget.dismiss(); //don't delete file that existed previously! throw; } //we cannot set the target file times while the file descriptor is open and being written: //this triggers bugs on samba shares where the modification time is set to current time instead. //http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=340236 //http://comments.gmane.org/gmane.linux.file-systems.cifs/2854 //on the other hand we thereby have to reopen https://sourceforge.net/p/freefilesync/bugs/230/ setFileTime(targetFile, sourceInfo.st_mtime, SYMLINK_FOLLOW); //throw FileError guardTarget.dismiss(); //target has been created successfully! } #endif Zstring findUnusedTempName(const Zstring& filename) { Zstring output = filename + zen::TEMP_FILE_ENDING; //ensure uniqueness (+ minor file system race condition!) for (int i = 1; somethingExists(output); ++i) output = filename + Zchar('_') + numberTo(i) + zen::TEMP_FILE_ENDING; return output; } /* ------------------ |File Copy Layers| ------------------ copyFile (setup transactional behavior) | copyFileSelectOs / \ copyFileLinuxMac copyFileWindows (solve 8.3 issue) | copyFileWindowsSelectRoutine / \ copyFileWindowsDefault(::CopyFileEx) copyFileWindowsSparse(::BackupRead/::BackupWrite) */ inline void copyFileSelectOs(const Zstring& sourceFile, const Zstring& targetFile, CallbackCopyFile* callback, FileAttrib* sourceAttr) { #ifdef FFS_WIN copyFileWindows(sourceFile, targetFile, callback, sourceAttr); //throw FileError, ErrorTargetPathMissing, ErrorTargetExisting, ErrorFileLocked #elif defined FFS_LINUX || defined FFS_MAC copyFileLinuxMac(sourceFile, targetFile, callback, sourceAttr); //throw FileError, ErrorTargetPathMissing, ErrorTargetExisting #endif } } void zen::copyFile(const Zstring& sourceFile, //throw FileError, ErrorTargetPathMissing, ErrorFileLocked const Zstring& targetFile, bool copyFilePermissions, bool transactionalCopy, CallbackCopyFile* callback, FileAttrib* sourceAttr) { if (transactionalCopy) { Zstring temporary = targetFile + zen::TEMP_FILE_ENDING; //use temporary file until a correct date has been set zen::ScopeGuard guardTempFile = zen::makeGuard([&] { try { removeFile(temporary); } catch (...) {} }); //transactional behavior: ensure cleanup (e.g. network drop) -> ref to temporary[!] //raw file copy try { copyFileSelectOs(sourceFile, temporary, callback, sourceAttr); //throw FileError: ErrorTargetPathMissing, ErrorTargetExisting, ErrorFileLocked } catch (ErrorTargetExisting&) { //determine non-used temp file name "first": //using optimistic strategy: assume everything goes well, but recover on error -> minimize file accesses temporary = findUnusedTempName(targetFile); //retry copyFileSelectOs(sourceFile, temporary, callback, sourceAttr); //throw FileError } //have target file deleted (after read access on source and target has been confirmed) => allow for almost transactional overwrite if (callback) callback->deleteTargetFile(targetFile); //rename temporary file: //perf: this call is REALLY expensive on unbuffered volumes! ~40% performance decrease on FAT USB stick! renameFile(temporary, targetFile); //throw FileError /* CAVEAT on FAT/FAT32: the sequence of deleting the target file and renaming "file.txt.ffs_tmp" to "file.txt" does NOT PRESERVE the creation time of the .ffs_tmp file, but SILENTLY "reuses" whatever creation time the old "file.txt" had! This "feature" is called "File System Tunneling": http://blogs.msdn.com/b/oldnewthing/archive/2005/07/15/439261.aspx http://support.microsoft.com/kb/172190/en-us However during the next comparison the DST hack will be applied correctly since the DST-hash of the mod.time is invalid. EXCEPTION: the hash may match!!! reproduce: 1. set system time back to date within previous DST 2. save some file on FAT32 usb stick and FFS-compare to make sure the DST hack is applied correctly 4. pull out usb stick, put back in 3. restore system time 4. copy file from USB to local drive via explorer => NTFS <-> FAT, file exists on both sides; mod times match, DST hack on USB stick causes 1-hour offset when comparing in FFS. When syncing modification time is copied correctly, but new DST hack fails to apply and old creation time is reused (see above). Unfortunately, the old DST hash matches mod time! => On next comparison FFS will *still* see both sides as different!!!!!!!!! */ guardTempFile.dismiss(); } else { //have target file deleted if (callback) callback->deleteTargetFile(targetFile); copyFileSelectOs(sourceFile, targetFile, callback, sourceAttr); //throw FileError: ErrorTargetPathMissing, ErrorTargetExisting, ErrorFileLocked } /* Note: non-transactional file copy solves at least four problems: -> skydrive - doesn't allow for .ffs_tmp extension and returns ERROR_INVALID_PARAMETER -> network renaming issues -> allow for true delete before copy to handle low disk space problems -> higher performance on non-buffered drives (e.g. usb sticks) */ //file permissions if (copyFilePermissions) { zen::ScopeGuard guardTargetFile = zen::makeGuard([&] { try { removeFile(targetFile); } catch (...) {}}); copyObjectPermissions(sourceFile, targetFile, SYMLINK_FOLLOW); //throw FileError guardTargetFile.dismiss(); //target has been created successfully! } }