protected override void HandleError(int errorCode)
{
TrySetException(Win32Marshal.GetExceptionForWin32Error(errorCode));
}
// Waits for a pipe instance to become available. This method may return before WaitForConnection is called
// on the server end, but WaitForConnection will not return until we have returned. Any data written to the
// pipe by us after we have connected but before the server has called WaitForConnection will be available
// to the server after it calls WaitForConnection.
private bool TryConnect(int timeout, CancellationToken cancellationToken)
{
Interop.Kernel32.SECURITY_ATTRIBUTES secAttrs = PipeStream.GetSecAttrs(_inheritability);
// PipeOptions.CurrentUserOnly is special since it doesn't match directly to a corresponding Win32 valid flag.
// Remove it, while keeping others untouched since historically this has been used as a way to pass flags to
// CreateNamedPipeClient that were not defined in the enumeration.
int _pipeFlags = (int)(_pipeOptions & ~PipeOptions.CurrentUserOnly);
if (_impersonationLevel != TokenImpersonationLevel.None)
{
_pipeFlags |= Interop.Kernel32.SecurityOptions.SECURITY_SQOS_PRESENT;
_pipeFlags |= (((int)_impersonationLevel - 1) << 16);
}
int access = 0;
if ((PipeDirection.In & _direction) != 0)
{
access |= Interop.Kernel32.GenericOperations.GENERIC_READ;
}
if ((PipeDirection.Out & _direction) != 0)
{
access |= Interop.Kernel32.GenericOperations.GENERIC_WRITE;
}
SafePipeHandle handle = CreateNamedPipeClient(_normalizedPipePath, ref secAttrs, _pipeFlags, access);
if (handle.IsInvalid)
{
int errorCode = Marshal.GetLastPInvokeError();
// CreateFileW: "If the CreateNamedPipe function was not successfully called on the server prior to this operation,
// a pipe will not exist and CreateFile will fail with ERROR_FILE_NOT_FOUND"
// WaitNamedPipeW: "If no instances of the specified named pipe exist,
// the WaitNamedPipe function returns immediately, regardless of the time-out value."
// We know that no instances exist, so we just quit without calling WaitNamedPipeW.
if (errorCode == Interop.Errors.ERROR_FILE_NOT_FOUND)
{
return(false);
}
if (errorCode != Interop.Errors.ERROR_PIPE_BUSY)
{
throw Win32Marshal.GetExceptionForWin32Error(errorCode);
}
if (!Interop.Kernel32.WaitNamedPipe(_normalizedPipePath, timeout))
{
errorCode = Marshal.GetLastPInvokeError();
if (errorCode == Interop.Errors.ERROR_FILE_NOT_FOUND || // server has been closed
errorCode == Interop.Errors.ERROR_SEM_TIMEOUT)
{
return(false);
}
throw Win32Marshal.GetExceptionForWin32Error(errorCode);
}
// Pipe server should be free. Let's try to connect to it.
handle = CreateNamedPipeClient(_normalizedPipePath, ref secAttrs, _pipeFlags, access);
if (handle.IsInvalid)
{
errorCode = Marshal.GetLastPInvokeError();
// WaitNamedPipe: "A subsequent CreateFile call to the pipe can fail,
// because the instance was closed by the server or opened by another client."
if (errorCode == Interop.Errors.ERROR_PIPE_BUSY || // opened by another client
errorCode == Interop.Errors.ERROR_FILE_NOT_FOUND) // server has been closed
{
return(false);
}
throw Win32Marshal.GetExceptionForWin32Error(errorCode);
}
}
// Success!
InitializeHandle(handle, false, (_pipeOptions & PipeOptions.Asynchronous) != 0);
State = PipeState.Connected;
ValidateRemotePipeUser();
return(true);
// Waits for a pipe instance to become available. This method may return before WaitForConnection is called
// on the server end, but WaitForConnection will not return until we have returned. Any data written to the
// pipe by us after we have connected but before the server has called WaitForConnection will be available
// to the server after it calls WaitForConnection.
private bool TryConnect(int timeout, CancellationToken cancellationToken)
{
Interop.Kernel32.SECURITY_ATTRIBUTES secAttrs = PipeStream.GetSecAttrs(_inheritability);
// PipeOptions.CurrentUserOnly is special since it doesn't match directly to a corresponding Win32 valid flag.
// Remove it, while keeping others untouched since historically this has been used as a way to pass flags to
// CreateNamedPipeClient that were not defined in the enumeration.
int _pipeFlags = (int)(_pipeOptions & ~PipeOptions.CurrentUserOnly);
if (_impersonationLevel != TokenImpersonationLevel.None)
{
_pipeFlags |= Interop.Kernel32.SecurityOptions.SECURITY_SQOS_PRESENT;
_pipeFlags |= (((int)_impersonationLevel - 1) << 16);
}
int access = 0;
if ((PipeDirection.In & _direction) != 0)
{
access |= Interop.Kernel32.GenericOperations.GENERIC_READ;
}
if ((PipeDirection.Out & _direction) != 0)
{
access |= Interop.Kernel32.GenericOperations.GENERIC_WRITE;
}
// Let's try to connect first
SafePipeHandle handle = Interop.Kernel32.CreateNamedPipeClient(_normalizedPipePath,
access, // read and write access
0, // sharing: none
ref secAttrs, // security attributes
FileMode.Open, // open existing
_pipeFlags, // impersonation flags
IntPtr.Zero); // template file: null
if (handle.IsInvalid)
{
int errorCode = Marshal.GetLastWin32Error();
if (errorCode != Interop.Errors.ERROR_PIPE_BUSY &&
errorCode != Interop.Errors.ERROR_FILE_NOT_FOUND)
{
throw Win32Marshal.GetExceptionForWin32Error(errorCode);
}
if (!Interop.Kernel32.WaitNamedPipe(_normalizedPipePath, timeout))
{
errorCode = Marshal.GetLastWin32Error();
// Server is not yet created or a timeout occurred before a pipe instance was available.
if (errorCode == Interop.Errors.ERROR_FILE_NOT_FOUND ||
errorCode == Interop.Errors.ERROR_SEM_TIMEOUT)
{
return(false);
}
throw Win32Marshal.GetExceptionForWin32Error(errorCode);
}
// Pipe server should be free. Let's try to connect to it.
handle = Interop.Kernel32.CreateNamedPipeClient(_normalizedPipePath,
access, // read and write access
0, // sharing: none
ref secAttrs, // security attributes
FileMode.Open, // open existing
_pipeFlags, // impersonation flags
IntPtr.Zero); // template file: null
if (handle.IsInvalid)
{
errorCode = Marshal.GetLastWin32Error();
// Handle the possible race condition of someone else connecting to the server
// between our calls to WaitNamedPipe & CreateFile.
if (errorCode == Interop.Errors.ERROR_PIPE_BUSY)
{
return(false);
}
throw Win32Marshal.GetExceptionForWin32Error(errorCode);
}
}
// Success!
InitializeHandle(handle, false, (_pipeOptions & PipeOptions.Asynchronous) != 0);
State = PipeState.Connected;
ValidateRemotePipeUser();
return(true);
}
private bool TryConnect(int timeout, CancellationToken cancellationToken)
{
Interop.Kernel32.SECURITY_ATTRIBUTES secAttrs = PipeStream.GetSecAttrs(_inheritability);
int _pipeFlags = (int)_pipeOptions;
if (_impersonationLevel != TokenImpersonationLevel.None)
{
_pipeFlags |= Interop.Kernel32.SecurityOptions.SECURITY_SQOS_PRESENT;
_pipeFlags |= (((int)_impersonationLevel - 1) << 16);
}
int access = 0;
if ((PipeDirection.In & _direction) != 0)
{
access |= Interop.Kernel32.GenericOperations.GENERIC_READ;
}
if ((PipeDirection.Out & _direction) != 0)
{
access |= Interop.Kernel32.GenericOperations.GENERIC_WRITE;
}
// Let's try to connect first
SafePipeHandle handle = Interop.Kernel32.CreateNamedPipeClient(_normalizedPipePath,
access, // read and write access
0, // sharing: none
ref secAttrs, // security attributes
FileMode.Open, // open existing
_pipeFlags, // impersonation flags
IntPtr.Zero); // template file: null
if (handle.IsInvalid)
{
int errorCode = Marshal.GetLastWin32Error();
if (errorCode != Interop.Errors.ERROR_PIPE_BUSY &&
errorCode != Interop.Errors.ERROR_FILE_NOT_FOUND)
{
throw Win32Marshal.GetExceptionForWin32Error(errorCode);
}
if (!Interop.Kernel32.WaitNamedPipe(_normalizedPipePath, timeout))
{
errorCode = Marshal.GetLastWin32Error();
// Server is not yet created
if (errorCode == Interop.Errors.ERROR_FILE_NOT_FOUND)
{
return(false);
}
// The timeout has expired.
if (errorCode == Interop.Errors.ERROR_SUCCESS)
{
if (cancellationToken.CanBeCanceled)
{
// It may not be real timeout.
return(false);
}
throw new TimeoutException();
}
throw Win32Marshal.GetExceptionForWin32Error(errorCode);
}
// Pipe server should be free. Let's try to connect to it.
handle = Interop.Kernel32.CreateNamedPipeClient(_normalizedPipePath,
access, // read and write access
0, // sharing: none
ref secAttrs, // security attributes
FileMode.Open, // open existing
_pipeFlags, // impersonation flags
IntPtr.Zero); // template file: null
if (handle.IsInvalid)
{
errorCode = Marshal.GetLastWin32Error();
// Handle the possible race condition of someone else connecting to the server
// between our calls to WaitNamedPipe & CreateFile.
if (errorCode == Interop.Errors.ERROR_PIPE_BUSY)
{
return(false);
}
throw Win32Marshal.GetExceptionForWin32Error(errorCode);
}
}
// Success!
InitializeHandle(handle, false, (_pipeOptions & PipeOptions.Asynchronous) != 0);
State = PipeState.Connected;
return(true);
}
unsafe private PipeStreamAsyncResult BeginReadCore(byte[] buffer, int offset, int count,
AsyncCallback callback, Object state)
{
Debug.Assert(_handle != null, "_handle is null");
Debug.Assert(!_handle.IsClosed, "_handle is closed");
Debug.Assert(CanRead, "can't read");
Debug.Assert(buffer != null, "buffer == null");
Debug.Assert(_isAsync, "BeginReadCore doesn't work on synchronous file streams!");
Debug.Assert(offset >= 0, "offset is negative");
Debug.Assert(count >= 0, "count is negative");
// Create and store async stream class library specific data in the async result
PipeStreamAsyncResult asyncResult = new PipeStreamAsyncResult();
asyncResult._handle = _handle;
asyncResult._userCallback = callback;
asyncResult._userStateObject = state;
asyncResult._isWrite = false;
// handle zero-length buffers separately; fixed keyword ReadFileNative doesn't like
// 0-length buffers. Call user callback and we're done
if (buffer.Length == 0)
{
asyncResult.CallUserCallback();
}
else
{
// For Synchronous IO, I could go with either a userCallback and using
// the managed Monitor class, or I could create a handle and wait on it.
ManualResetEvent waitHandle = new ManualResetEvent(false);
asyncResult._waitHandle = waitHandle;
// Create a managed overlapped class; set the file offsets later
Overlapped overlapped = new Overlapped();
overlapped.OffsetLow = 0;
overlapped.OffsetHigh = 0;
overlapped.AsyncResult = asyncResult;
// Pack the Overlapped class, and store it in the async result
NativeOverlapped *intOverlapped;
intOverlapped = overlapped.Pack(s_IOCallback, buffer);
asyncResult._overlapped = intOverlapped;
// Queue an async ReadFile operation and pass in a packed overlapped
int errorCode = 0;
int r = ReadFileNative(_handle, buffer, offset, count, intOverlapped, out errorCode);
// ReadFile, the OS version, will return 0 on failure, but this ReadFileNative wrapper
// returns -1. This will return the following:
// - On error, r==-1.
// - On async requests that are still pending, r==-1 w/ hr==ERROR_IO_PENDING
// - On async requests that completed sequentially, r==0
//
// You will NEVER RELIABLY be able to get the number of buffer 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)
{
// One side has closed its handle or server disconnected. Set the state to Broken
// and do some cleanup work
if (errorCode == Interop.ERROR_BROKEN_PIPE ||
errorCode == Interop.ERROR_PIPE_NOT_CONNECTED)
{
State = PipeState.Broken;
// Clear the overlapped status bit for this special case. Failure to do so looks
// like we are freeing a pending overlapped.
intOverlapped->InternalLow = IntPtr.Zero;
// EndRead will free the Overlapped struct
asyncResult.CallUserCallback();
}
else if (errorCode != Interop.ERROR_IO_PENDING)
{
throw Win32Marshal.GetExceptionForWin32Error(errorCode);
}
}
ReadWriteAsyncParams readWriteParams = state as ReadWriteAsyncParams;
if (readWriteParams != null)
{
if (readWriteParams.CancellationHelper != null)
{
readWriteParams.CancellationHelper.AllowCancellation(_handle, intOverlapped);
}
}
}
return(asyncResult);
}
private unsafe void EndWaitForConnection(IAsyncResult asyncResult)
{
CheckConnectOperationsServerWithHandle();
if (asyncResult == null)
{
throw new ArgumentNullException("asyncResult");
}
if (!IsAsync)
{
throw new InvalidOperationException(SR.InvalidOperation_PipeNotAsync);
}
PipeAsyncResult afsar = asyncResult as PipeAsyncResult;
if (afsar == null)
{
throw __Error.GetWrongAsyncResult();
}
// Ensure we can't get into any races by doing an interlocked
// CompareExchange here. Avoids corrupting memory via freeing the
// NativeOverlapped class or GCHandle twice. --
if (1 == Interlocked.CompareExchange(ref afsar._EndXxxCalled, 1, 0))
{
throw __Error.GetEndWaitForConnectionCalledTwice();
}
IOCancellationHelper cancellationHelper = afsar.AsyncState as IOCancellationHelper;
if (cancellationHelper != null)
{
cancellationHelper.SetOperationCompleted();
}
// Obtain the WaitHandle, but don't use public property in case we
// delay initialize the manual reset event in the future.
WaitHandle wh = afsar._waitHandle;
if (wh != null)
{
// We must block to ensure that ConnectionIOCallback has completed,
// and we should close the WaitHandle in here. AsyncFSCallback
// and the hand-ported imitation version in COMThreadPool.cpp
// are the only places that set this event.
using (wh)
{
wh.WaitOne();
Debug.Assert(afsar._isComplete == true, "NamedPipeServerStream::EndWaitForConnection - AsyncFSCallback didn't set _isComplete to true!");
}
}
// We should have freed the overlapped and set it to null either in the Begin
// method (if ConnectNamedPipe completed synchronously) or in AsyncWaitForConnectionCallback.
// If it is not nulled out, we should not be past the above wait:
Debug.Assert(afsar._overlapped == null);
// Now check for any error during the read.
if (afsar._errorCode != 0)
{
if (afsar._errorCode == Interop.ERROR_OPERATION_ABORTED)
{
if (cancellationHelper != null)
{
cancellationHelper.ThrowIOOperationAborted();
}
}
throw Win32Marshal.GetExceptionForWin32Error(afsar._errorCode);
}
// Success
State = PipeState.Connected;
}
private unsafe IAsyncResult BeginWaitForConnection(AsyncCallback callback, Object state)
{
CheckConnectOperationsServerWithHandle();
if (!IsAsync)
{
throw new InvalidOperationException(SR.InvalidOperation_PipeNotAsync);
}
// Create and store async stream class library specific data in the
// async result
PipeAsyncResult asyncResult = new PipeAsyncResult();
asyncResult._handle = InternalHandle;
asyncResult._userCallback = callback;
asyncResult._userStateObject = state;
IOCancellationHelper cancellationHelper = state as IOCancellationHelper;
// Create wait handle and store in async result
ManualResetEvent waitHandle = new ManualResetEvent(false);
asyncResult._waitHandle = waitHandle;
// Create a managed overlapped class
// We will set the file offsets later
Overlapped overlapped = new Overlapped();
overlapped.OffsetLow = 0;
overlapped.OffsetHigh = 0;
overlapped.AsyncResult = asyncResult;
// Pack the Overlapped class, and store it in the async result
NativeOverlapped *intOverlapped = overlapped.Pack(s_WaitForConnectionCallback, null);
asyncResult._overlapped = intOverlapped;
if (!Interop.mincore.ConnectNamedPipe(InternalHandle, intOverlapped))
{
int errorCode = Marshal.GetLastWin32Error();
if (errorCode == Interop.ERROR_IO_PENDING)
{
if (cancellationHelper != null)
{
cancellationHelper.AllowCancellation(InternalHandle, intOverlapped);
}
return(asyncResult);
}
// WaitForConnectionCallback will not be called because we completed synchronously.
// Either the pipe is already connected, or there was an error. Unpin and free the overlapped again.
Overlapped.Free(intOverlapped);
asyncResult._overlapped = null;
// Did the client already connect to us?
if (errorCode == Interop.ERROR_PIPE_CONNECTED)
{
if (State == PipeState.Connected)
{
throw new InvalidOperationException(SR.InvalidOperation_PipeAlreadyConnected);
}
asyncResult.CallUserCallback();
return(asyncResult);
}
throw Win32Marshal.GetExceptionForWin32Error(errorCode);
}
// will set state to Connected when EndWait is called
if (cancellationHelper != null)
{
cancellationHelper.AllowCancellation(InternalHandle, intOverlapped);
}
return(asyncResult);
}
private Task <int> ReadAsyncCorePrivate(byte[] buffer, int offset, int count, CancellationToken cancellationToken)
{
Debug.Assert(_handle != null, "_handle is null");
Debug.Assert(!_handle.IsClosed, "_handle is closed");
Debug.Assert(CanRead, "can't read");
Debug.Assert(buffer != null, "buffer == null");
Debug.Assert(_isAsync, "ReadAsyncCorePrivate doesn't work on synchronous file streams!");
Debug.Assert(offset >= 0, "offset is negative");
Debug.Assert(count >= 0, "count is negative");
if (buffer.Length == 0)
{
UpdateMessageCompletion(false);
return(s_zeroTask);
}
else
{
var completionSource = new ReadWriteCompletionSource(this, buffer, cancellationToken, isWrite: false);
// Queue an async ReadFile operation and pass in a packed overlapped
int errorCode = 0;
int r;
unsafe
{
r = ReadFileNative(_handle, buffer, offset, count, completionSource.Overlapped, out errorCode);
}
// ReadFile, the OS version, will return 0 on failure, but this ReadFileNative wrapper
// returns -1. This will return the following:
// - On error, r==-1.
// - On async requests that are still pending, r==-1 w/ hr==ERROR_IO_PENDING
// - On async requests that completed sequentially, r==0
//
// You will NEVER RELIABLY be able to get the number of buffer 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)
{
switch (errorCode)
{
// One side has closed its handle or server disconnected.
// Set the state to Broken and do some cleanup work
case Interop.mincore.Errors.ERROR_BROKEN_PIPE:
case Interop.mincore.Errors.ERROR_PIPE_NOT_CONNECTED:
State = PipeState.Broken;
unsafe
{
// Clear the overlapped status bit for this special case. Failure to do so looks
// like we are freeing a pending overlapped.
completionSource.Overlapped->InternalLow = IntPtr.Zero;
}
completionSource.ReleaseResources();
UpdateMessageCompletion(true);
return(s_zeroTask);
case Interop.mincore.Errors.ERROR_IO_PENDING:
break;
default:
throw Win32Marshal.GetExceptionForWin32Error(errorCode);
}
}
completionSource.RegisterForCancellation();
return(completionSource.Task);
}
}
protected override void HandleError(int errorCode) => TrySetException(ExceptionDispatchInfo.SetCurrentStackTrace(Win32Marshal.GetExceptionForWin32Error(errorCode)));
