static private GetExceptionForWin32Error ( int errorCode ) : |
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errorCode | int | |
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private static unsafe void WriteSyncUsingAsyncHandle(SafeFileHandle handle, ReadOnlySpan <byte> buffer, long fileOffset) { if (buffer.IsEmpty) { return; } handle.EnsureThreadPoolBindingInitialized(); CallbackResetEvent resetEvent = new CallbackResetEvent(handle.ThreadPoolBinding !); NativeOverlapped * overlapped = null; try { overlapped = GetNativeOverlappedForAsyncHandle(handle.ThreadPoolBinding !, fileOffset, resetEvent); fixed(byte *pinned = &MemoryMarshal.GetReference(buffer)) { Interop.Kernel32.WriteFile(handle, pinned, buffer.Length, IntPtr.Zero, overlapped); int errorCode = FileStreamHelpers.GetLastWin32ErrorAndDisposeHandleIfInvalid(handle); if (errorCode == Interop.Errors.ERROR_IO_PENDING) { resetEvent.WaitOne(); errorCode = Interop.Errors.ERROR_SUCCESS; } if (errorCode == Interop.Errors.ERROR_SUCCESS) { int result = 0; if (Interop.Kernel32.GetOverlappedResult(handle, overlapped, ref result, bWait: false)) { Debug.Assert(result == buffer.Length, $"GetOverlappedResult returned {result} for {buffer.Length} bytes request"); return; } errorCode = FileStreamHelpers.GetLastWin32ErrorAndDisposeHandleIfInvalid(handle); } switch (errorCode) { case Interop.Errors.ERROR_NO_DATA: // For pipes, ERROR_NO_DATA is not an error, but the pipe is closing. return; case Interop.Errors.ERROR_INVALID_PARAMETER: // ERROR_INVALID_PARAMETER may be returned for writes // where the position is too large or for synchronous writes // to a handle opened asynchronously. throw new IOException(SR.IO_FileTooLong); default: throw Win32Marshal.GetExceptionForWin32Error(errorCode, handle.Path); } } } finally { if (overlapped != null) { resetEvent.FreeNativeOverlapped(overlapped); } resetEvent.Dispose(); } }
private SafeFileHandle OpenHandle(FileMode mode, FileShare share, FileOptions options) { Interop.Kernel32.SECURITY_ATTRIBUTES secAttrs = GetSecAttrs(share); int fAccess = ((_access & FileAccess.Read) == FileAccess.Read ? GENERIC_READ : 0) | ((_access & FileAccess.Write) == FileAccess.Write ? GENERIC_WRITE : 0); // Our Inheritable bit was stolen from Windows, but should be set in // the security attributes class. Don't leave this bit set. share &= ~FileShare.Inheritable; // Must use a valid Win32 constant here... if (mode == FileMode.Append) { mode = FileMode.OpenOrCreate; } int flagsAndAttributes = (int)options; // For mitigating local elevation of privilege attack through named pipes // make sure we always call CreateFile with SECURITY_ANONYMOUS so that the // named pipe server can't impersonate a high privileged client security context flagsAndAttributes |= (Interop.Kernel32.SecurityOptions.SECURITY_SQOS_PRESENT | Interop.Kernel32.SecurityOptions.SECURITY_ANONYMOUS); // Don't pop up a dialog for reading from an empty floppy drive uint oldMode = Interop.Kernel32.SetErrorMode(Interop.Kernel32.SEM_FAILCRITICALERRORS); try { SafeFileHandle fileHandle = Interop.Kernel32.CreateFile(_path, fAccess, share, ref secAttrs, mode, flagsAndAttributes, IntPtr.Zero); fileHandle.IsAsync = _useAsyncIO; if (fileHandle.IsInvalid) { // Return a meaningful exception with the full path. // NT5 oddity - when trying to open "C:\" as a Win32FileStream, // we usually get ERROR_PATH_NOT_FOUND from the OS. We should // probably be consistent w/ every other directory. int errorCode = Marshal.GetLastWin32Error(); if (errorCode == Interop.Errors.ERROR_PATH_NOT_FOUND && _path.Length == PathInternal.GetRootLength(_path)) { errorCode = Interop.Errors.ERROR_ACCESS_DENIED; } throw Win32Marshal.GetExceptionForWin32Error(errorCode, _path); } int fileType = Interop.Kernel32.GetFileType(fileHandle); if (fileType != Interop.Kernel32.FileTypes.FILE_TYPE_DISK) { fileHandle.Dispose(); throw new NotSupportedException(SR.NotSupported_FileStreamOnNonFiles); } return(fileHandle); } finally { Interop.Kernel32.SetErrorMode(oldMode); } }
public static void CreateDirectory(string fullPath) { // We can save a bunch of work if the directory we want to create already exists. This also // saves us in the case where sub paths are inaccessible (due to ERROR_ACCESS_DENIED) but the // final path is accessible and the directory already exists. For example, consider trying // to create c:\Foo\Bar\Baz, where everything already exists but ACLS prevent access to c:\Foo // and c:\Foo\Bar. In that case, this code will think it needs to create c:\Foo, and c:\Foo\Bar // and fail to due so, causing an exception to be thrown. This is not what we want. if (DirectoryExists(fullPath)) { return; } List <string> stackDir = new List <string>(); // Attempt to figure out which directories don't exist, and only // create the ones we need. Note that FileExists may fail due // to Win32 ACL's preventing us from seeing a directory, and this // isn't threadsafe. bool somepathexists = false; int length = fullPath.Length; // We need to trim the trailing slash or the code will try to create 2 directories of the same name. if (length >= 2 && PathInternal.EndsInDirectorySeparator(fullPath)) { length--; } int lengthRoot = PathInternal.GetRootLength(fullPath); if (length > lengthRoot) { // Special case root (fullpath = X:\\) int i = length - 1; while (i >= lengthRoot && !somepathexists) { string dir = fullPath.Substring(0, i + 1); if (!DirectoryExists(dir)) // Create only the ones missing { stackDir.Add(dir); } else { somepathexists = true; } while (i > lengthRoot && !PathInternal.IsDirectorySeparator(fullPath[i])) { i--; } i--; } } int count = stackDir.Count; // If we were passed a DirectorySecurity, convert it to a security // descriptor and set it in he call to CreateDirectory. Interop.Kernel32.SECURITY_ATTRIBUTES secAttrs = default; bool r = true; int firstError = 0; string errorString = fullPath; // If all the security checks succeeded create all the directories while (stackDir.Count > 0) { string name = stackDir[stackDir.Count - 1]; stackDir.RemoveAt(stackDir.Count - 1); r = Interop.Kernel32.CreateDirectory(name, ref secAttrs); if (!r && (firstError == 0)) { int currentError = Marshal.GetLastWin32Error(); // While we tried to avoid creating directories that don't // exist above, there are at least two cases that will // cause us to see ERROR_ALREADY_EXISTS here. FileExists // can fail because we didn't have permission to the // directory. Secondly, another thread or process could // create the directory between the time we check and the // time we try using the directory. Thirdly, it could // fail because the target does exist, but is a file. if (currentError != Interop.Errors.ERROR_ALREADY_EXISTS) { firstError = currentError; } else { // If there's a file in this directory's place, or if we have ERROR_ACCESS_DENIED when checking if the directory already exists throw. if (FileExists(name) || (!DirectoryExists(name, out currentError) && currentError == Interop.Errors.ERROR_ACCESS_DENIED)) { firstError = currentError; errorString = name; } } } } // We need this check to mask OS differences // Handle CreateDirectory("X:\\") when X: doesn't exist. Similarly for n/w paths. if ((count == 0) && !somepathexists) { string root = Directory.InternalGetDirectoryRoot(fullPath); if (!DirectoryExists(root)) { throw Win32Marshal.GetExceptionForWin32Error(Interop.Errors.ERROR_PATH_NOT_FOUND, root); } return; } // Only throw an exception if creating the exact directory we // wanted failed to work correctly. if (!r && (firstError != 0)) { throw Win32Marshal.GetExceptionForWin32Error(firstError, errorString); } }
private async Task <FileStreamBase> OpenAsync(string fullPath, FileMode mode, FileAccess access, FileShare share, int bufferSize, FileOptions options) { // Win32 CreateFile returns ERROR_PATH_NOT_FOUND when given a path that ends with '\' if (PathHelpers.EndsInDirectorySeparator(fullPath)) { throw Win32Marshal.GetExceptionForWin32Error(Interop.ERROR_PATH_NOT_FOUND, fullPath); } StorageFile file = null; // FileMode if (mode == FileMode.Open || mode == FileMode.Truncate) { file = await StorageFile.GetFileFromPathAsync(fullPath).TranslateWinRTTask(fullPath); } else { CreationCollisionOption collisionOptions; switch (mode) { case FileMode.Create: collisionOptions = CreationCollisionOption.ReplaceExisting; break; case FileMode.CreateNew: collisionOptions = CreationCollisionOption.FailIfExists; break; case FileMode.Append: case FileMode.OpenOrCreate: default: collisionOptions = CreationCollisionOption.OpenIfExists; break; } string directoryPath, fileName; PathHelpers.SplitDirectoryFile(fullPath, out directoryPath, out fileName); StorageFolder directory = await StorageFolder.GetFolderFromPathAsync(directoryPath).TranslateWinRTTask(directoryPath, isDirectory: true); file = await directory.CreateFileAsync(fileName, collisionOptions).TranslateWinRTTask(fullPath); } // FileAccess: WinRT doesn't support FileAccessMode.Write so we upgrade to ReadWrite FileAccessMode accessMode = ((access & FileAccess.Write) != 0) ? FileAccessMode.ReadWrite : FileAccessMode.Read; // FileShare: cannot translate StorageFile uses a different sharing model (oplocks) that is controlled via FileAccessMode // FileOptions: ignore most values of FileOptions as they are hints and are not supported by WinRT. // FileOptions.Encrypted is not a hint, and not supported by WinRT, but there is precedent for ignoring this (FAT). // FileOptions.DeleteOnClose should result in an UnauthorizedAccessException when // opening a file that can only be read, but we cannot safely reproduce that behavior // in WinRT without actually deleting the file. // Instead the failure will occur in the finalizer for WinRTFileStream and be ignored. // open our stream Stream stream = (await file.OpenAsync(accessMode).TranslateWinRTTask(fullPath)).AsStream(bufferSize); if (mode == FileMode.Append) { // seek to end. stream.Seek(0, SeekOrigin.End); } else if (mode == FileMode.Truncate) { // truncate stream to 0 stream.SetLength(0); } return(new WinRTFileStream(stream, file, access, options)); }
/// <summary> /// Gets reparse point information associated to <paramref name="linkPath"/>. /// </summary> /// <returns>The immediate link target, absolute or relative or null if the file is not a supported link.</returns> internal static unsafe string?GetImmediateLinkTarget(string linkPath, bool isDirectory, bool throwOnError, bool returnFullPath) { using SafeFileHandle handle = OpenSafeFileHandle(linkPath, Interop.Kernel32.FileOperations.FILE_FLAG_BACKUP_SEMANTICS | Interop.Kernel32.FileOperations.FILE_FLAG_OPEN_REPARSE_POINT); if (handle.IsInvalid) { if (!throwOnError) { return(null); } int error = Marshal.GetLastWin32Error(); // File not found doesn't make much sense coming from a directory. if (isDirectory && error == Interop.Errors.ERROR_FILE_NOT_FOUND) { error = Interop.Errors.ERROR_PATH_NOT_FOUND; } throw Win32Marshal.GetExceptionForWin32Error(error, linkPath); } byte[] buffer = ArrayPool <byte> .Shared.Rent(Interop.Kernel32.MAXIMUM_REPARSE_DATA_BUFFER_SIZE); try { bool success = Interop.Kernel32.DeviceIoControl( handle, dwIoControlCode: Interop.Kernel32.FSCTL_GET_REPARSE_POINT, lpInBuffer: IntPtr.Zero, nInBufferSize: 0, lpOutBuffer: buffer, nOutBufferSize: Interop.Kernel32.MAXIMUM_REPARSE_DATA_BUFFER_SIZE, out _, IntPtr.Zero); if (!success) { if (!throwOnError) { return(null); } int error = Marshal.GetLastWin32Error(); // The file or directory is not a reparse point. if (error == Interop.Errors.ERROR_NOT_A_REPARSE_POINT) { return(null); } throw Win32Marshal.GetExceptionForWin32Error(error, linkPath); } Span <byte> bufferSpan = new(buffer); success = MemoryMarshal.TryRead(bufferSpan, out Interop.Kernel32.SymbolicLinkReparseBuffer rbSymlink); Debug.Assert(success); // We always use SubstituteName(Offset|Length) instead of PrintName(Offset|Length), // the latter is just the display name of the reparse point and it can show something completely unrelated to the target. if (rbSymlink.ReparseTag == Interop.Kernel32.IOReparseOptions.IO_REPARSE_TAG_SYMLINK) { int offset = sizeof(Interop.Kernel32.SymbolicLinkReparseBuffer) + rbSymlink.SubstituteNameOffset; int length = rbSymlink.SubstituteNameLength; Span <char> targetPath = MemoryMarshal.Cast <byte, char>(bufferSpan.Slice(offset, length)); bool isRelative = (rbSymlink.Flags & Interop.Kernel32.SYMLINK_FLAG_RELATIVE) != 0; if (!isRelative) { // Absolute target is in NT format and we need to clean it up before return it to the user. if (targetPath.StartsWith(PathInternal.UncNTPathPrefix.AsSpan())) { // We need to prepend the Win32 equivalent of UNC NT prefix. return(Path.Join(PathInternal.UncPathPrefix.AsSpan(), targetPath.Slice(PathInternal.UncNTPathPrefix.Length))); } return(GetTargetPathWithoutNTPrefix(targetPath)); } else if (returnFullPath) { return(Path.Join(Path.GetDirectoryName(linkPath.AsSpan()), targetPath)); } else { return(targetPath.ToString()); } } else if (rbSymlink.ReparseTag == Interop.Kernel32.IOReparseOptions.IO_REPARSE_TAG_MOUNT_POINT) { success = MemoryMarshal.TryRead(bufferSpan, out Interop.Kernel32.MountPointReparseBuffer rbMountPoint); Debug.Assert(success); int offset = sizeof(Interop.Kernel32.MountPointReparseBuffer) + rbMountPoint.SubstituteNameOffset; int length = rbMountPoint.SubstituteNameLength; Span <char> targetPath = MemoryMarshal.Cast <byte, char>(bufferSpan.Slice(offset, length)); // Unlike symbolic links, mount point paths cannot be relative. Debug.Assert(!PathInternal.IsPartiallyQualified(targetPath)); // Mount points cannot point to a remote location. Debug.Assert(!targetPath.StartsWith(PathInternal.UncNTPathPrefix.AsSpan())); return(GetTargetPathWithoutNTPrefix(targetPath)); } return(null); } finally { ArrayPool <byte> .Shared.Return(buffer); }
private static void RemoveDirectoryRecursive(string fullPath, ref Interop.Kernel32.WIN32_FIND_DATA findData, bool topLevel) { int errorCode; Exception exception = null; using (SafeFindHandle handle = Interop.Kernel32.FindFirstFile(Path.Join(fullPath, "*"), ref findData)) { if (handle.IsInvalid) { throw Win32Marshal.GetExceptionForLastWin32Error(fullPath); } do { if ((findData.dwFileAttributes & Interop.Kernel32.FileAttributes.FILE_ATTRIBUTE_DIRECTORY) == 0) { // File string fileName = findData.cFileName.GetStringFromFixedBuffer(); if (!Interop.Kernel32.DeleteFile(Path.Combine(fullPath, fileName)) && exception == null) { errorCode = Marshal.GetLastWin32Error(); // We don't care if something else deleted the file first if (errorCode != Interop.Errors.ERROR_FILE_NOT_FOUND) { exception = Win32Marshal.GetExceptionForWin32Error(errorCode, fileName); } } } else { // Directory, skip ".", "..". if (findData.cFileName.FixedBufferEqualsString(".") || findData.cFileName.FixedBufferEqualsString("..")) { continue; } string fileName = findData.cFileName.GetStringFromFixedBuffer(); if (!IsNameSurrogateReparsePoint(ref findData)) { // Not a reparse point, or the reparse point isn't a name surrogate, recurse. try { RemoveDirectoryRecursive( Path.Combine(fullPath, fileName), findData: ref findData, topLevel: false); } catch (Exception e) { if (exception == null) { exception = e; } } } else { // Name surrogate reparse point, don't recurse, simply remove the directory. // If a mount point, we have to delete the mount point first. if (findData.dwReserved0 == Interop.Kernel32.IOReparseOptions.IO_REPARSE_TAG_MOUNT_POINT) { // Mount point. Unmount using full path plus a trailing '\'. // (Note: This doesn't remove the underlying directory) string mountPoint = Path.Join(fullPath, fileName, PathInternal.DirectorySeparatorCharAsString); if (!Interop.Kernel32.DeleteVolumeMountPoint(mountPoint) && exception == null) { errorCode = Marshal.GetLastWin32Error(); if (errorCode != Interop.Errors.ERROR_SUCCESS && errorCode != Interop.Errors.ERROR_PATH_NOT_FOUND) { exception = Win32Marshal.GetExceptionForWin32Error(errorCode, fileName); } } } // Note that RemoveDirectory on a symbolic link will remove the link itself. if (!Interop.Kernel32.RemoveDirectory(Path.Combine(fullPath, fileName)) && exception == null) { errorCode = Marshal.GetLastWin32Error(); if (errorCode != Interop.Errors.ERROR_PATH_NOT_FOUND) { exception = Win32Marshal.GetExceptionForWin32Error(errorCode, fileName); } } } } } while (Interop.Kernel32.FindNextFile(handle, ref findData)); if (exception != null) { throw exception; } errorCode = Marshal.GetLastWin32Error(); if (errorCode != Interop.Errors.ERROR_SUCCESS && errorCode != Interop.Errors.ERROR_NO_MORE_FILES) { throw Win32Marshal.GetExceptionForWin32Error(errorCode, fullPath); } } // As we successfully removed all of the files we shouldn't care about the directory itself // not being empty. As file deletion is just a marker to remove the file when all handles // are closed we could still have contents hanging around. RemoveDirectoryInternal(fullPath, topLevel: topLevel, allowDirectoryNotEmpty: true); }
[System.Security.SecurityCritical] // auto-generated private unsafe static string NormalizePath(string path, bool fullCheck, int maxPathLength, bool expandShortPaths) { Contract.Requires(path != null, "path can't be null"); // If the path is in extended syntax, we don't need to normalize, but we still do some basic validity checks if (PathInternal.IsExtended(path)) { if (!ValidateExtendedPath(path, fullCheck)) { throw new ArgumentException(SR.Arg_PathIllegal); } // \\?\GLOBALROOT gives access to devices out of the scope of the current user, we // don't want to allow this for security reasons. // https://msdn.microsoft.com/en-us/library/windows/desktop/aa365247.aspx#nt_namespaces if (path.StartsWith(@"\\?\globalroot", StringComparison.OrdinalIgnoreCase)) { throw new ArgumentException(SR.Arg_PathGlobalRoot); } return(path); } // If we're doing a full path check, trim whitespace and look for // illegal path characters. if (fullCheck) { // Trim whitespace off the end of the string. // Win32 normalization trims only U+0020. path = path.TrimEnd(TrimEndChars); // Look for illegal path characters. PathInternal.CheckInvalidPathChars(path); } int index = 0; // We prefer to allocate on the stack for workingset/perf gain. If the // starting path is less than MaxPath then we can stackalloc; otherwise we'll // use a StringBuilder (PathHelper does this under the hood). The latter may // happen in 2 cases: // 1. Starting path is greater than MaxPath but it normalizes down to MaxPath. // This is relevant for paths containing escape sequences. In this case, we // attempt to normalize down to MaxPath, but the caller pays a perf penalty // since StringBuilder is used. // 2. IsolatedStorage, which supports paths longer than MaxPath (value given // by maxPathLength. PathHelper newBuffer = null; if (path.Length + 1 <= MaxPath) { char *m_arrayPtr = stackalloc char[MaxPath]; newBuffer = new PathHelper(m_arrayPtr, MaxPath); } else { newBuffer = new PathHelper(path.Length + MaxPath, maxPathLength); } uint numSpaces = 0; uint numDots = 0; bool fixupDirectorySeparator = false; // Number of significant chars other than potentially suppressible // dots and spaces since the last directory or volume separator char uint numSigChars = 0; int lastSigChar = -1; // Index of last significant character. // Whether this segment of the path (not the complete path) started // with a volume separator char. Reject "c:...". bool startedWithVolumeSeparator = false; bool firstSegment = true; int lastDirectorySeparatorPos = 0; bool mightBeShortFileName = false; // LEGACY: This code is here for backwards compatibility reasons. It // ensures that \\foo.cs\bar.cs stays \\foo.cs\bar.cs instead of being // turned into \foo.cs\bar.cs. if (path.Length > 0 && PathInternal.IsDirectorySeparator(path[0])) { newBuffer.Append('\\'); index++; lastSigChar = 0; } // Normalize the string, stripping out redundant dots, spaces, and // slashes. while (index < path.Length) { char currentChar = path[index]; // We handle both directory separators and dots specially. For // directory separators, we consume consecutive appearances. // For dots, we consume all dots beyond the second in // succession. All other characters are added as is. In // addition we consume all spaces after the last other char // in a directory name up until the directory separator. if (PathInternal.IsDirectorySeparator(currentChar)) { // If we have a path like "123.../foo", remove the trailing dots. // However, if we found "c:\temp\..\bar" or "c:\temp\...\bar", don't. // Also remove trailing spaces from both files & directory names. // This was agreed on with the OS team to fix undeletable directory // names ending in spaces. // If we saw a '\' as the previous last significant character and // are simply going to write out dots, suppress them. // If we only contain dots and slashes though, only allow // a string like [dot]+ [space]*. Ignore everything else. // Legal: "\.. \", "\...\", "\. \" // Illegal: "\.. .\", "\. .\", "\ .\" if (numSigChars == 0) { // Dot and space handling if (numDots > 0) { // Look for ".[space]*" or "..[space]*" int start = lastSigChar + 1; if (path[start] != '.') { throw new ArgumentException(SR.Arg_PathIllegal); } // Only allow "[dot]+[space]*", and normalize the // legal ones to "." or ".." if (numDots >= 2) { // Reject "C:..." if (startedWithVolumeSeparator && numDots > 2) { throw new ArgumentException(SR.Arg_PathIllegal); } if (path[start + 1] == '.') { // Search for a space in the middle of the // dots and throw for (int i = start + 2; i < start + numDots; i++) { if (path[i] != '.') { throw new ArgumentException(SR.Arg_PathIllegal); } } numDots = 2; } else { if (numDots > 1) { throw new ArgumentException(SR.Arg_PathIllegal); } numDots = 1; } } if (numDots == 2) { newBuffer.Append('.'); } newBuffer.Append('.'); fixupDirectorySeparator = false; // Continue in this case, potentially writing out '\'. } if (numSpaces > 0 && firstSegment) { // Handle strings like " \\server\share". if (index + 1 < path.Length && PathInternal.IsDirectorySeparator(path[index + 1])) { newBuffer.Append(DirectorySeparatorChar); } } } numDots = 0; numSpaces = 0; // Suppress trailing spaces if (!fixupDirectorySeparator) { fixupDirectorySeparator = true; newBuffer.Append(DirectorySeparatorChar); } numSigChars = 0; lastSigChar = index; startedWithVolumeSeparator = false; firstSegment = false; // For short file names, we must try to expand each of them as // soon as possible. We need to allow people to specify a file // name that doesn't exist using a path with short file names // in it, such as this for a temp file we're trying to create: // C:\DOCUME~1\USERNA~1.RED\LOCALS~1\Temp\bg3ylpzp // We could try doing this afterwards piece by piece, but it's // probably a lot simpler to do it here. if (mightBeShortFileName) { newBuffer.TryExpandShortFileName(); mightBeShortFileName = false; } int thisPos = newBuffer.Length - 1; if (thisPos - lastDirectorySeparatorPos > MaxComponentLength) { throw new PathTooLongException(SR.IO_PathTooLong); } lastDirectorySeparatorPos = thisPos; } // if (Found directory separator) else if (currentChar == '.') { // Reduce only multiple .'s only after slash to 2 dots. For // instance a...b is a valid file name. numDots++; // Don't flush out non-terminal spaces here, because they may in // the end not be significant. Turn "c:\ . .\foo" -> "c:\foo" // which is the conclusion of removing trailing dots & spaces, // as well as folding multiple '\' characters. } else if (currentChar == ' ') { numSpaces++; } else { // Normal character logic if (currentChar == '~' && expandShortPaths) { mightBeShortFileName = true; } fixupDirectorySeparator = false; // To reject strings like "C:...\foo" and "C :\foo" if (firstSegment && currentChar == VolumeSeparatorChar) { // Only accept "C:", not "c :" or ":" // Get a drive letter or ' ' if index is 0. char driveLetter = (index > 0) ? path[index - 1] : ' '; bool validPath = ((numDots == 0) && (numSigChars >= 1) && (driveLetter != ' ')); if (!validPath) { throw new ArgumentException(SR.Arg_PathIllegal); } startedWithVolumeSeparator = true; // We need special logic to make " c:" work, we should not fix paths like " foo::$DATA" if (numSigChars > 1) { // Common case, simply do nothing int spaceCount = 0; // How many spaces did we write out, numSpaces has already been reset. while ((spaceCount < newBuffer.Length) && newBuffer[spaceCount] == ' ') { spaceCount++; } if (numSigChars - spaceCount == 1) { //Safe to update stack ptr directly newBuffer.Length = 0; newBuffer.Append(driveLetter); // Overwrite spaces, we need a special case to not break " foo" as a relative path. } } numSigChars = 0; } else { numSigChars += 1 + numDots + numSpaces; } // Copy any spaces & dots since the last significant character // to here. Note we only counted the number of dots & spaces, // and don't know what order they're in. Hence the copy. if (numDots > 0 || numSpaces > 0) { int numCharsToCopy = (lastSigChar >= 0) ? index - lastSigChar - 1 : index; if (numCharsToCopy > 0) { for (int i = 0; i < numCharsToCopy; i++) { newBuffer.Append(path[lastSigChar + 1 + i]); } } numDots = 0; numSpaces = 0; } newBuffer.Append(currentChar); lastSigChar = index; } index++; } // end while if (newBuffer.Length - 1 - lastDirectorySeparatorPos > MaxComponentLength) { throw new PathTooLongException(SR.IO_PathTooLong); } // Drop any trailing dots and spaces from file & directory names, EXCEPT // we MUST make sure that "C:\foo\.." is correctly handled. // Also handle "C:\foo\." -> "C:\foo", while "C:\." -> "C:\" if (numSigChars == 0) { if (numDots > 0) { // Look for ".[space]*" or "..[space]*" int start = lastSigChar + 1; if (path[start] != '.') { throw new ArgumentException(SR.Arg_PathIllegal); } // Only allow "[dot]+[space]*", and normalize the // legal ones to "." or ".." if (numDots >= 2) { // Reject "C:..." if (startedWithVolumeSeparator && numDots > 2) { throw new ArgumentException(SR.Arg_PathIllegal); } if (path[start + 1] == '.') { // Search for a space in the middle of the // dots and throw for (int i = start + 2; i < start + numDots; i++) { if (path[i] != '.') { throw new ArgumentException(SR.Arg_PathIllegal); } } numDots = 2; } else { if (numDots > 1) { throw new ArgumentException(SR.Arg_PathIllegal); } numDots = 1; } } if (numDots == 2) { newBuffer.Append('.'); } newBuffer.Append('.'); } } // if (numSigChars == 0) // If we ended up eating all the characters, bail out. if (newBuffer.Length == 0) { throw new ArgumentException(SR.Arg_PathIllegal); } // Disallow URL's here. Some of our other Win32 API calls will reject // them later, so we might be better off rejecting them here. // Note we've probably turned them into "file:\D:\foo.tmp" by now. // But for compatibility, ensure that callers that aren't doing a // full check aren't rejected here. if (fullCheck) { if (newBuffer.OrdinalStartsWith("http:", false) || newBuffer.OrdinalStartsWith("file:", false)) { throw new ArgumentException(SR.Argument_PathUriFormatNotSupported); } } // If the last part of the path (file or directory name) had a tilde, // expand that too. if (mightBeShortFileName) { newBuffer.TryExpandShortFileName(); } // Call the Win32 API to do the final canonicalization step. int result = 1; if (fullCheck) { // NOTE: Win32 GetFullPathName requires the input buffer to be big enough to fit the initial // path which is a concat of CWD and the relative path, this can be of an arbitrary // size and could be > MaxPath (which becomes an artificial limit at this point), // even though the final normalized path after fixing up the relative path syntax // might be well within the MaxPath restriction. For ex, // "c:\SomeReallyLongDirName(thinkGreaterThan_MAXPATH)\..\foo.txt" which actually requires a // buffer well with in the MaxPath as the normalized path is just "c:\foo.txt" // This buffer requirement seems wrong, it could be a bug or a perf optimization // like returning required buffer length quickly or avoid stratch buffer etc. // Either way we need to workaround it here... // Ideally we would get the required buffer length first by calling GetFullPathName // once without the buffer and use that in the later call but this doesn't always work // due to Win32 GetFullPathName bug. For instance, in Win2k, when the path we are trying to // fully qualify is a single letter name (such as "a", "1", ",") GetFullPathName // fails to return the right buffer size (i.e, resulting in insufficient buffer). // To workaround this bug we will start with MaxPath buffer and grow it once if the // return value is > MaxPath. result = newBuffer.GetFullPathName(); // If we called GetFullPathName with something like "foo" and our // command window was in short file name mode (ie, by running edlin or // DOS versions of grep, etc), we might have gotten back a short file // name. So, check to see if we need to expand it. mightBeShortFileName = false; for (int i = 0; i < newBuffer.Length && !mightBeShortFileName; i++) { if (newBuffer[i] == '~' && expandShortPaths) { mightBeShortFileName = true; } } if (mightBeShortFileName) { bool r = newBuffer.TryExpandShortFileName(); // Consider how the path "Doesn'tExist" would expand. If // we add in the current directory, it too will need to be // fully expanded, which doesn't happen if we use a file // name that doesn't exist. if (!r) { int lastSlash = -1; for (int i = newBuffer.Length - 1; i >= 0; i--) { if (newBuffer[i] == DirectorySeparatorChar) { lastSlash = i; break; } } if (lastSlash >= 0) { // This bounds check is for safe memcpy but we should never get this far if (newBuffer.Length >= maxPathLength) { throw new PathTooLongException(SR.IO_PathTooLong); } int lenSavedName = newBuffer.Length - lastSlash - 1; Debug.Assert(lastSlash < newBuffer.Length, "path unexpectedly ended in a '\'"); newBuffer.Fixup(lenSavedName, lastSlash); } } } } if (result != 0) { /* Throw an ArgumentException for paths like \\, \\server, \\server\ * This check can only be properly done after normalizing, so \\foo\.. will be properly rejected. */ if (newBuffer.Length > 1 && newBuffer[0] == '\\' && newBuffer[1] == '\\') { int startIndex = 2; while (startIndex < result) { if (newBuffer[startIndex] == '\\') { startIndex++; break; } else { startIndex++; } } if (startIndex == result) { throw new ArgumentException(SR.Arg_PathIllegalUNC); } } } // Check our result and form the managed string as necessary. if (newBuffer.Length >= maxPathLength) { throw new PathTooLongException(SR.IO_PathTooLong); } if (result == 0) { int errorCode = Marshal.GetLastWin32Error(); if (errorCode == 0) { errorCode = Interop.mincore.Errors.ERROR_BAD_PATHNAME; } throw Win32Marshal.GetExceptionForWin32Error(errorCode, path); } string returnVal = newBuffer.ToString(); if (string.Equals(returnVal, path, StringComparison.Ordinal)) { returnVal = path; } return(returnVal); }
[System.Security.SecurityCritical] // auto-generated private static void RemoveDirectoryHelper(string fullPath, bool recursive, bool throwOnTopLevelDirectoryNotFound) { bool r; int errorCode; Exception ex = null; // Do not recursively delete through reparse points. Perhaps in a // future version we will add a new flag to control this behavior, // but for now we're much safer if we err on the conservative side. // This applies to symbolic links and mount points. // Note the logic to check whether fullPath is a reparse point is // in Delete(String, String, bool), and will set "recursive" to false. // Note that Win32's DeleteFile and RemoveDirectory will just delete // the reparse point itself. if (recursive) { Interop.mincore.WIN32_FIND_DATA data = new Interop.mincore.WIN32_FIND_DATA(); // Open a Find handle using (SafeFindHandle hnd = Interop.mincore.FindFirstFile(Directory.EnsureTrailingDirectorySeparator(fullPath) + "*", ref data)) { if (hnd.IsInvalid) { throw Win32Marshal.GetExceptionForLastWin32Error(fullPath); } do { bool isDir = (0 != (data.dwFileAttributes & Interop.mincore.FileAttributes.FILE_ATTRIBUTE_DIRECTORY)); if (isDir) { // Skip ".", "..". if (data.cFileName.Equals(".") || data.cFileName.Equals("..")) { continue; } // Recurse for all directories, unless they are // reparse points. Do not follow mount points nor // symbolic links, but do delete the reparse point // itself. bool shouldRecurse = (0 == (data.dwFileAttributes & (int)FileAttributes.ReparsePoint)); if (shouldRecurse) { string newFullPath = Path.Combine(fullPath, data.cFileName); try { RemoveDirectoryHelper(newFullPath, recursive, false); } catch (Exception e) { if (ex == null) { ex = e; } } } else { // Check to see if this is a mount point, and // unmount it. if (data.dwReserved0 == Interop.mincore.IOReparseOptions.IO_REPARSE_TAG_MOUNT_POINT) { // Use full path plus a trailing '\' String mountPoint = Path.Combine(fullPath, data.cFileName + PathHelpers.DirectorySeparatorCharAsString); if (!Interop.mincore.DeleteVolumeMountPoint(mountPoint)) { errorCode = Marshal.GetLastWin32Error(); if (errorCode != Interop.mincore.Errors.ERROR_SUCCESS && errorCode != Interop.mincore.Errors.ERROR_PATH_NOT_FOUND) { try { throw Win32Marshal.GetExceptionForWin32Error(errorCode, data.cFileName); } catch (Exception e) { if (ex == null) { ex = e; } } } } } // RemoveDirectory on a symbolic link will // remove the link itself. String reparsePoint = Path.Combine(fullPath, data.cFileName); r = Interop.mincore.RemoveDirectory(reparsePoint); if (!r) { errorCode = Marshal.GetLastWin32Error(); if (errorCode != Interop.mincore.Errors.ERROR_PATH_NOT_FOUND) { try { throw Win32Marshal.GetExceptionForWin32Error(errorCode, data.cFileName); } catch (Exception e) { if (ex == null) { ex = e; } } } } } } else { String fileName = Path.Combine(fullPath, data.cFileName); r = Interop.mincore.DeleteFile(fileName); if (!r) { errorCode = Marshal.GetLastWin32Error(); if (errorCode != Interop.mincore.Errors.ERROR_FILE_NOT_FOUND) { try { throw Win32Marshal.GetExceptionForWin32Error(errorCode, data.cFileName); } catch (Exception e) { if (ex == null) { ex = e; } } } } } } while (Interop.mincore.FindNextFile(hnd, ref data)); // Make sure we quit with a sensible error. errorCode = Marshal.GetLastWin32Error(); } if (ex != null) { throw ex; } if (errorCode != 0 && errorCode != Interop.mincore.Errors.ERROR_NO_MORE_FILES) { throw Win32Marshal.GetExceptionForWin32Error(errorCode, fullPath); } } r = Interop.mincore.RemoveDirectory(fullPath); if (!r) { errorCode = Marshal.GetLastWin32Error(); if (errorCode == Interop.mincore.Errors.ERROR_FILE_NOT_FOUND) // A dubious error code. { errorCode = Interop.mincore.Errors.ERROR_PATH_NOT_FOUND; } // This check was originally put in for Win9x (unfortunately without special casing it to be for Win9x only). We can't change the NT codepath now for backcomp reasons. if (errorCode == Interop.mincore.Errors.ERROR_ACCESS_DENIED) { throw new IOException(SR.Format(SR.UnauthorizedAccess_IODenied_Path, fullPath)); } // don't throw the DirectoryNotFoundException since this is a subdir and // there could be a race condition between two Directory.Delete callers if (errorCode == Interop.mincore.Errors.ERROR_PATH_NOT_FOUND && !throwOnTopLevelDirectoryNotFound) { return; } throw Win32Marshal.GetExceptionForWin32Error(errorCode, fullPath); } }
private unsafe Task <int> ReadAsyncInternal(Memory <byte> destination, CancellationToken cancellationToken = default) { if (!CanRead) { ThrowHelper.ThrowNotSupportedException_UnreadableStream(); } Debug.Assert(!_fileHandle.IsClosed, "!_handle.IsClosed"); // Create and store async stream class library specific data in the async result FileStreamCompletionSource completionSource = FileStreamCompletionSource.Create(this, _preallocatedOverlapped, 0, destination); NativeOverlapped * intOverlapped = completionSource.Overlapped; // Calculate position in the file we should be at after the read is done if (CanSeek) { long len = Length; // Make sure we are reading from the position that we think we are VerifyOSHandlePosition(); if (destination.Length > len - _filePosition) { if (_filePosition <= len) { destination = destination.Slice(0, (int)(len - _filePosition)); } else { destination = default; } } // Now set the position to read from in the NativeOverlapped struct // For pipes, we should leave the offset fields set to 0. intOverlapped->OffsetLow = unchecked ((int)_filePosition); intOverlapped->OffsetHigh = (int)(_filePosition >> 32); // When using overlapped IO, the OS is not supposed to // touch the file pointer location at all. We will adjust it // ourselves. This isn't threadsafe. // WriteFile should not update the file pointer when writing // in overlapped mode, according to MSDN. But it does update // the file pointer when writing to a UNC path! // So changed the code below to seek to an absolute // location, not a relative one. ReadFile seems consistent though. SeekCore(_fileHandle, destination.Length, SeekOrigin.Current); } // queue an async ReadFile operation and pass in a packed overlapped int r = FileStreamHelpers.ReadFileNative(_fileHandle, destination.Span, intOverlapped, out int errorCode); // ReadFile, the OS version, will return 0 on failure. But // my ReadFileNative wrapper returns -1. My wrapper will return // the following: // On error, r==-1. // On async requests that are still pending, r==-1 w/ errorCode==ERROR_IO_PENDING // on async requests that completed sequentially, r==0 // You will NEVER RELIABLY be able to get the number of bytes // read back from this call when using overlapped structures! You must // not pass in a non-null lpNumBytesRead to ReadFile when using // overlapped structures! This is by design NT behavior. if (r == -1) { // For pipes, when they hit EOF, they will come here. if (errorCode == ERROR_BROKEN_PIPE) { // Not an error, but EOF. AsyncFSCallback will NOT be // called. Call the user callback here. // We clear the overlapped status bit for this special case. // Failure to do so looks like we are freeing a pending overlapped later. intOverlapped->InternalLow = IntPtr.Zero; completionSource.SetCompletedSynchronously(0); } else if (errorCode != ERROR_IO_PENDING) { if (!_fileHandle.IsClosed && CanSeek) // Update Position - It could be anywhere. { SeekCore(_fileHandle, 0, SeekOrigin.Current); } completionSource.ReleaseNativeResource(); if (errorCode == ERROR_HANDLE_EOF) { ThrowHelper.ThrowEndOfFileException(); } else { throw Win32Marshal.GetExceptionForWin32Error(errorCode, _path); } } else if (cancellationToken.CanBeCanceled) // ERROR_IO_PENDING { // Only once the IO is pending do we register for cancellation completionSource.RegisterForCancellation(cancellationToken); } } else { // Due to a workaround for a race condition in NT's ReadFile & // WriteFile routines, we will always be returning 0 from ReadFileNative // when we do async IO instead of the number of bytes read, // irregardless of whether the operation completed // synchronously or asynchronously. We absolutely must not // set asyncResult._numBytes here, since will never have correct // results. } return(completionSource.Task); }
private unsafe Task WriteAsyncInternalCore(ReadOnlyMemory <byte> source, CancellationToken cancellationToken) { if (!CanWrite) { ThrowHelper.ThrowNotSupportedException_UnwritableStream(); } Debug.Assert(!_fileHandle.IsClosed, "!_handle.IsClosed"); // Create and store async stream class library specific data in the async result FileStreamCompletionSource completionSource = FileStreamCompletionSource.Create(this, _preallocatedOverlapped, 0, source); NativeOverlapped * intOverlapped = completionSource.Overlapped; if (CanSeek) { // Make sure we set the length of the file appropriately. long len = Length; // Make sure we are writing to the position that we think we are VerifyOSHandlePosition(); if (_filePosition + source.Length > len) { SetLengthCore(_filePosition + source.Length); } // Now set the position to read from in the NativeOverlapped struct // For pipes, we should leave the offset fields set to 0. intOverlapped->OffsetLow = (int)_filePosition; intOverlapped->OffsetHigh = (int)(_filePosition >> 32); // When using overlapped IO, the OS is not supposed to // touch the file pointer location at all. We will adjust it // ourselves. This isn't threadsafe. SeekCore(_fileHandle, source.Length, SeekOrigin.Current); } // queue an async WriteFile operation and pass in a packed overlapped int r = FileStreamHelpers.WriteFileNative(_fileHandle, source.Span, intOverlapped, out int errorCode); // WriteFile, the OS version, will return 0 on failure. But // my WriteFileNative wrapper returns -1. My wrapper will return // the following: // On error, r==-1. // On async requests that are still pending, r==-1 w/ errorCode==ERROR_IO_PENDING // On async requests that completed sequentially, r==0 // You will NEVER RELIABLY be able to get the number of bytes // written back from this call when using overlapped IO! You must // not pass in a non-null lpNumBytesWritten to WriteFile when using // overlapped structures! This is ByDesign NT behavior. if (r == -1) { // For pipes, when they are closed on the other side, they will come here. if (errorCode == ERROR_NO_DATA) { // Not an error, but EOF. AsyncFSCallback will NOT be called. // Completing TCS and return cached task allowing the GC to collect TCS. completionSource.SetCompletedSynchronously(0); return(Task.CompletedTask); } else if (errorCode != ERROR_IO_PENDING) { if (!_fileHandle.IsClosed && CanSeek) // Update Position - It could be anywhere. { SeekCore(_fileHandle, 0, SeekOrigin.Current); } completionSource.ReleaseNativeResource(); if (errorCode == ERROR_HANDLE_EOF) { ThrowHelper.ThrowEndOfFileException(); } else { throw Win32Marshal.GetExceptionForWin32Error(errorCode, _path); } } else if (cancellationToken.CanBeCanceled) // ERROR_IO_PENDING { // Only once the IO is pending do we register for cancellation completionSource.RegisterForCancellation(cancellationToken); } } else { // Due to a workaround for a race condition in NT's ReadFile & // WriteFile routines, we will always be returning 0 from WriteFileNative // when we do async IO instead of the number of bytes written, // irregardless of whether the operation completed // synchronously or asynchronously. We absolutely must not // set asyncResult._numBytes here, since will never have correct // results. } return(completionSource.Task); }
private void HandleError(int errorCode, string path) { Dispose(); throw Win32Marshal.GetExceptionForWin32Error(errorCode, path); }
private Exception HandleError(int errorCode, string path) { Dispose(); return(Win32Marshal.GetExceptionForWin32Error(errorCode, path)); }
private void HandleError(int hr, String path) { Dispose(); throw Win32Marshal.GetExceptionForWin32Error(hr, path); }
private static unsafe int ReadSyncUsingAsyncHandle(SafeFileHandle handle, Span <byte> buffer, long fileOffset) { handle.EnsureThreadPoolBindingInitialized(); CallbackResetEvent resetEvent = new CallbackResetEvent(handle.ThreadPoolBinding !); NativeOverlapped * overlapped = null; try { overlapped = GetNativeOverlappedForAsyncHandle(handle, fileOffset, resetEvent); fixed(byte *pinned = &MemoryMarshal.GetReference(buffer)) { Interop.Kernel32.ReadFile(handle, pinned, buffer.Length, IntPtr.Zero, overlapped); int errorCode = FileStreamHelpers.GetLastWin32ErrorAndDisposeHandleIfInvalid(handle); if (errorCode == Interop.Errors.ERROR_IO_PENDING) { resetEvent.WaitOne(); errorCode = Interop.Errors.ERROR_SUCCESS; } if (errorCode == Interop.Errors.ERROR_SUCCESS) { int result = 0; if (Interop.Kernel32.GetOverlappedResult(handle, overlapped, ref result, bWait: false)) { Debug.Assert(result >= 0 && result <= buffer.Length, $"GetOverlappedResult returned {result} for {buffer.Length} bytes request"); return(result); } errorCode = FileStreamHelpers.GetLastWin32ErrorAndDisposeHandleIfInvalid(handle); } switch (errorCode) { case Interop.Errors.ERROR_HANDLE_EOF: // logically success with 0 bytes read (read at end of file) case Interop.Errors.ERROR_BROKEN_PIPE: case Interop.Errors.ERROR_INVALID_PARAMETER when IsEndOfFileForNoBuffering(handle, fileOffset): // EOF on a pipe. Callback will not be called. // We clear the overlapped status bit for this special case (failure // to do so looks like we are freeing a pending overlapped later). overlapped->InternalLow = IntPtr.Zero; return(0); default: throw Win32Marshal.GetExceptionForWin32Error(errorCode, handle.Path); } } } finally { if (overlapped != null) { resetEvent.FreeNativeOverlapped(overlapped); } resetEvent.Dispose(); } }
private static void RemoveDirectoryRecursive(string fullPath, ref Interop.Kernel32.WIN32_FIND_DATA findData, bool topLevel) { int errorCode; Exception exception = null; using (SafeFindHandle handle = Interop.Kernel32.FindFirstFile(Directory.EnsureTrailingDirectorySeparator(fullPath) + "*", ref findData)) { if (handle.IsInvalid) { throw Win32Marshal.GetExceptionForLastWin32Error(fullPath); } do { if ((findData.dwFileAttributes & Interop.Kernel32.FileAttributes.FILE_ATTRIBUTE_DIRECTORY) == 0) { // File string fileName = findData.cFileName.GetStringFromFixedBuffer(); if (!Interop.Kernel32.DeleteFile(Path.Combine(fullPath, fileName)) && exception == null) { errorCode = Marshal.GetLastWin32Error(); // We don't care if something else deleted the file first if (errorCode != Interop.Errors.ERROR_FILE_NOT_FOUND) { exception = Win32Marshal.GetExceptionForWin32Error(errorCode, fileName); } } } else { // Directory, skip ".", "..". if (findData.cFileName.FixedBufferEqualsString(".") || findData.cFileName.FixedBufferEqualsString("..")) { continue; } string fileName = findData.cFileName.GetStringFromFixedBuffer(); if ((findData.dwFileAttributes & (int)FileAttributes.ReparsePoint) == 0) { // Not a reparse point, recurse. try { RemoveDirectoryRecursive( Path.Combine(fullPath, fileName), findData: ref findData, topLevel: false); } catch (Exception e) { if (exception == null) { exception = e; } } } else { // Reparse point, don't recurse, just remove. (dwReserved0 is documented for this flag) if (findData.dwReserved0 == Interop.Kernel32.IOReparseOptions.IO_REPARSE_TAG_MOUNT_POINT) { // Mount point. Unmount using full path plus a trailing '\'. // (Note: This doesn't remove the underlying directory) string mountPoint = Path.Combine(fullPath, fileName + PathHelpers.DirectorySeparatorCharAsString); if (!Interop.Kernel32.DeleteVolumeMountPoint(mountPoint) && exception == null) { errorCode = Marshal.GetLastWin32Error(); if (errorCode != Interop.Errors.ERROR_SUCCESS && errorCode != Interop.Errors.ERROR_PATH_NOT_FOUND) { exception = Win32Marshal.GetExceptionForWin32Error(errorCode, fileName); } } } // Note that RemoveDirectory on a symbolic link will remove the link itself. if (!Interop.Kernel32.RemoveDirectory(Path.Combine(fullPath, fileName)) && exception == null) { errorCode = Marshal.GetLastWin32Error(); if (errorCode != Interop.Errors.ERROR_PATH_NOT_FOUND) { exception = Win32Marshal.GetExceptionForWin32Error(errorCode, fileName); } } } } } while (Interop.Kernel32.FindNextFile(handle, ref findData)); if (exception != null) { throw exception; } errorCode = Marshal.GetLastWin32Error(); if (errorCode != Interop.Errors.ERROR_SUCCESS && errorCode != Interop.Errors.ERROR_NO_MORE_FILES) { throw Win32Marshal.GetExceptionForWin32Error(errorCode, fullPath); } } RemoveDirectoryInternal(fullPath, topLevel: topLevel); }