Code:
/ DotNET / DotNET / 8.0 / untmp / whidbey / REDBITS / ndp / fx / src / Net / System / Net / SecureProtocols / _HelperAsyncResults.cs / 1 / _HelperAsyncResults.cs
/*++ Copyright (c) 2000 Microsoft Corporation Module Name: _HelperAsyncResults.cs Abstract: These are simple helpers to keep track of protocol IO requests Author: Alexei Vopilov Aug 18 2003 Revision History: --*/ namespace System.Net { using System; using System.IO; using System.Threading; // // Simply said whenever we want to wrap a user IO request we need // to preserve the original request buffer & sizes. // // Usually we would return this class as IAsyncResult to application // internal class BufferAsyncResult: LazyAsyncResult { public byte[] Buffer; public BufferOffsetSize[] Buffers; public int Offset; public int Count; public bool IsWrite; // MultipleWriteOnly // public BufferAsyncResult(object asyncObject, BufferOffsetSize[] buffers, object asyncState, AsyncCallback asyncCallback) :base (asyncObject, asyncState, asyncCallback) { Buffers = buffers; IsWrite = true; } public BufferAsyncResult(object asyncObject, byte[] buffer, int offset, int count, object asyncState, AsyncCallback asyncCallback) :this(asyncObject, buffer, offset, count, false, asyncState, asyncCallback) { } public BufferAsyncResult(object asyncObject, byte[] buffer, int offset, int count, bool isWrite, object asyncState, AsyncCallback asyncCallback) :base (asyncObject, asyncState, asyncCallback) { Buffer = buffer; Offset = offset; Count = count; IsWrite = isWrite; } } // The callback type used with below AsyncProtocolRequest class internal delegate void AsyncProtocolCallback(AsyncProtocolRequest asyncRequest); // // The class mimics LazyAsyncResult although it does not need to be thread safe nor it does need an Event. // Usually we would use this class to implement iterative protocol logic // // The beauty is that // 1) it can be reused for handshake-like or multi-IO request protocols // 2) it is proven to not block async IO since there is NO event handler exposed // // UserAsyncResult property is a link into original user IO request (could be a BufferAsyncResult). // When underlined protocol is done this guy gets completed // internal class AsyncProtocolRequest { #if DEBUG internal object _DebugAsyncChain; // Optionally used to track chains of async calls. #endif private AsyncProtocolCallback _Callback; private int _CompletionStatus; const int StatusNotStarted = 0; const int StatusCompleted = 1; const int StatusCheckedOnSyncCompletion = 2; public LazyAsyncResult UserAsyncResult; public int Result; // it's always about read bytes or alike public object AsyncState; // sometime it's needed to communicate additional info. // Note that AsyncObject is just a link to UserAsyncResult.AsyncObject public byte[] Buffer; // temp buffer reused by a protocol. public int Offset; // ditto public int Count; // ditto // // public AsyncProtocolRequest(LazyAsyncResult userAsyncResult) { GlobalLog.Assert(userAsyncResult != null, "AsyncProtocolRequest()|userAsyncResult == null"); GlobalLog.Assert(!userAsyncResult.InternalPeekCompleted, "AsyncProtocolRequest()|userAsyncResult is already completed."); UserAsyncResult = userAsyncResult; } // // public void SetNextRequest(byte[] buffer, int offset, int count, AsyncProtocolCallback callback) { if (_CompletionStatus != StatusNotStarted) throw new InternalException(); // pending op is in progress Buffer = buffer; Offset = offset; Count = count; _Callback = callback; } // // internal object AsyncObject { get { return UserAsyncResult.AsyncObject; } } // // Notify protocol so a next stage could be started // internal void CompleteRequest(int result) { Result = result; int status = Interlocked.Exchange(ref _CompletionStatus, StatusCompleted); if (status == StatusCompleted) throw new InternalException(); // only allow one call if (status == StatusCheckedOnSyncCompletion) { _CompletionStatus = StatusNotStarted; _Callback(this); } } // public bool MustCompleteSynchronously { get { int status = Interlocked.Exchange(ref _CompletionStatus, StatusCheckedOnSyncCompletion); if (status == StatusCheckedOnSyncCompletion) throw new InternalException(); // only allow one call if (status == StatusCompleted) { _CompletionStatus = StatusNotStarted; return true; } return false; } } // // NB: This will abandon _Callback and directly notify UserAsyncResult. // internal void CompleteWithError(Exception e) { UserAsyncResult.InvokeCallback(e); } // internal void CompleteUser() { UserAsyncResult.InvokeCallback(); } // internal void CompleteUser(object userResult) { UserAsyncResult.InvokeCallback(userResult); } // internal bool IsUserCompleted { get {return UserAsyncResult.InternalPeekCompleted;} } } }
Link Menu

This book is available now!
Buy at Amazon US or
Buy at Amazon UK
- CodeEntryPointMethod.cs
- Control.cs
- Compiler.cs
- ValidationError.cs
- basecomparevalidator.cs
- MDIWindowDialog.cs
- Ticks.cs
- KeyManager.cs
- mda.cs
- HandlerMappingMemo.cs
- WebPartDescriptionCollection.cs
- SoapFormatter.cs
- followingsibling.cs
- CompatibleIComparer.cs
- Transaction.cs
- PublisherMembershipCondition.cs
- DbDataReader.cs
- PriorityQueue.cs
- Point3DKeyFrameCollection.cs
- NameHandler.cs
- UDPClient.cs
- XPathCompileException.cs
- DeploymentExceptionMapper.cs
- SessionSwitchEventArgs.cs
- ProcessModule.cs
- sqlmetadatafactory.cs
- SafeRegistryHandle.cs
- DependencyPropertyKind.cs
- BufferedReadStream.cs
- DateTimeFormatInfoScanner.cs
- ListBase.cs
- CultureSpecificCharacterBufferRange.cs
- Vector3dCollection.cs
- TypeTypeConverter.cs
- CatalogPart.cs
- ExpressionBinding.cs
- ApplicationFileParser.cs
- ComboBoxItem.cs
- Debugger.cs
- IsolatedStorageFile.cs
- ImageMap.cs
- AdapterUtil.cs
- MethodAccessException.cs
- StylusPointDescription.cs
- NamedPipeAppDomainProtocolHandler.cs
- TokenBasedSetEnumerator.cs
- PrincipalPermission.cs
- XmlLanguageConverter.cs
- DataContext.cs
- X509ChainPolicy.cs
- XsdDateTime.cs
- StylusPointProperty.cs
- X509ChainElement.cs
- Literal.cs
- ToolStripContentPanel.cs
- GrowingArray.cs
- DependencyPropertyDescriptor.cs
- ListBoxAutomationPeer.cs
- PropertyGroupDescription.cs
- XappLauncher.cs
- WorkflowServiceHost.cs
- CodeSnippetTypeMember.cs
- BreakRecordTable.cs
- FunctionImportMapping.cs
- Cursor.cs
- AutomationPropertyChangedEventArgs.cs
- ShaderEffect.cs
- GetWorkflowTree.cs
- SystemIPInterfaceStatistics.cs
- DataContractSet.cs
- Native.cs
- SparseMemoryStream.cs
- UnaryNode.cs
- OpenFileDialog.cs
- MatrixCamera.cs
- XmlFormatReaderGenerator.cs
- OrderedHashRepartitionEnumerator.cs
- ListViewItem.cs
- ConfigXmlAttribute.cs
- TreeNodeBinding.cs
- NumericPagerField.cs
- BreakRecordTable.cs
- ClientUIRequest.cs
- DataObjectEventArgs.cs
- ListViewTableRow.cs
- AudioFormatConverter.cs
- PropertyGroupDescription.cs
- AutomationPattern.cs
- XmlNamespaceMappingCollection.cs
- ContainerActivationHelper.cs
- StorageInfo.cs
- PerfService.cs
- ColorConverter.cs
- PerspectiveCamera.cs
- PeerResolver.cs
- _NestedMultipleAsyncResult.cs
- ScaleTransform3D.cs
- XmlSchemaSimpleContent.cs
- DataGridItemCollection.cs
- ActiveXMessageFormatter.cs