WaitHandle.cs source code in C# .NET

Source code for the .NET framework in C#

                        
Code:

                         / 4.0 / 4.0 / untmp / DEVDIV_TFS / Dev10 / Releases / RTMRel / ndp / clr / src / BCL / System / Threading / WaitHandle.cs / 1305376 / WaitHandle.cs
                        

                        
                            // ==++== 
//
//   Copyright (c) Microsoft Corporation.  All rights reserved.
//
// ==--== 
//
// [....] 
/*============================================================================== 
**
** Class: WaitHandle    (this name is NOT definitive) 
**
**
** Purpose: Class to represent all synchronization objects in the runtime (that allow multiple wait)
** 
**
=============================================================================*/ 
 
namespace System.Threading
{ 
    using System.Threading;
    using System.Runtime.Remoting;
    using System;
    using System.Security.Permissions; 
    using System.Runtime.CompilerServices;
    using System.Runtime.InteropServices; 
    using Microsoft.Win32.SafeHandles; 
    using System.Runtime.Versioning;
    using System.Runtime.ConstrainedExecution; 
    using System.Diagnostics.Contracts;
    using Win32Native = Microsoft.Win32.Win32Native;

[System.Runtime.InteropServices.ComVisible(true)] 
#if FEATURE_REMOTING
    public abstract class WaitHandle : MarshalByRefObject, IDisposable { 
#if false 
    }
#endif // false 
#else // FEATURE_REMOTING
    public abstract class WaitHandle : IDisposable {
#endif // FEATURE_REMOTING
        public const int WaitTimeout = 0x102; 

        private const int MAX_WAITHANDLES = 64; 
 
#pragma warning disable 414  // Field is not used from managed.
        private IntPtr waitHandle;  // !!! DO NOT MOVE THIS FIELD. (See defn of WAITHANDLEREF in object.h - has hardcoded access to this field.) 
#pragma warning restore 414

        [System.Security.SecurityCritical /*auto-generated*/]
        internal SafeWaitHandle safeWaitHandle; 

        internal bool hasThreadAffinity; 
 
        [System.Security.SecuritySafeCritical]  // auto-generated
        private static IntPtr GetInvalidHandle() 
        {
            return Win32Native.INVALID_HANDLE_VALUE;
        }
        protected static readonly IntPtr InvalidHandle = GetInvalidHandle(); 
        private const int WAIT_OBJECT_0 = 0;
        private const int WAIT_ABANDONED = 0x80; 
        private const int WAIT_FAILED = 0x7FFFFFFF; 
        private const int ERROR_TOO_MANY_POSTS = 0x12A;
 
        protected WaitHandle()
        {
            Init();
        } 
        [System.Security.SecuritySafeCritical]  // auto-generated
        private void Init() 
        { safeWaitHandle = null; 
          waitHandle = InvalidHandle;
            hasThreadAffinity = false; 
        }


        [Obsolete("Use the SafeWaitHandle property instead.")] 
        public virtual IntPtr Handle
        { 
             [System.Security.SecuritySafeCritical]  // auto-generated 
             [ResourceExposure(ResourceScope.Machine)]
             [ResourceConsumption(ResourceScope.Machine)] 
             get { return safeWaitHandle == null ? InvalidHandle : safeWaitHandle.DangerousGetHandle();}

             [System.Security.SecurityCritical]  // auto-generated_required
             [SecurityPermissionAttribute(SecurityAction.InheritanceDemand, Flags=SecurityPermissionFlag.UnmanagedCode)] 
             [ResourceExposure(ResourceScope.Machine)]
             [ResourceConsumption(ResourceScope.Machine)] 
            set 
            {
                if (value == InvalidHandle) 
                {
                     // This line leaks a handle.  However, it's currently
                     // not perfectly clear what the right behavior is here
                     // anyways.  This preserves Everett behavior.  We should 
                     // ideally do these things:
                     // *) Expose a settable SafeHandle property on WaitHandle. 
                     // *) Expose a settable OwnsHandle property on SafeHandle. 
                     // We're looking into this.   -- [....]
                    if (safeWaitHandle != null) 
                    {
                     safeWaitHandle.SetHandleAsInvalid();
                     safeWaitHandle = null;
                 } 
                }
                else 
                { 
                     safeWaitHandle = new SafeWaitHandle(value, true);
                 } 
                 waitHandle = value;
             }
        }
 

        public SafeWaitHandle SafeWaitHandle 
        { 
             [System.Security.SecurityCritical]  // auto-generated_required
             [SecurityPermissionAttribute(SecurityAction.InheritanceDemand, Flags=SecurityPermissionFlag.UnmanagedCode)] 
             [ResourceExposure(ResourceScope.Machine)]
             [ResourceConsumption(ResourceScope.Machine)]
             [ReliabilityContract(Consistency.WillNotCorruptState, Cer.MayFail)]
            get 
            {
                if (safeWaitHandle == null) 
                { 
                    safeWaitHandle = new SafeWaitHandle(InvalidHandle, false);
                } 
                return safeWaitHandle;
             }

             [System.Security.SecurityCritical]  // auto-generated_required 
             [SecurityPermissionAttribute(SecurityAction.InheritanceDemand, Flags=SecurityPermissionFlag.UnmanagedCode)]
             [ResourceExposure(ResourceScope.Machine)] 
             [ResourceConsumption(ResourceScope.Machine)] 
             [ReliabilityContract(Consistency.WillNotCorruptState, Cer.Success)]
            set 
            {
                 // Set safeWaitHandle and waitHandle in a CER so we won't take
                 // a thread abort between the statements and leave the wait
                 // handle in an invalid state. Note this routine is not thread 
                 // safe however.
                 RuntimeHelpers.PrepareConstrainedRegions(); 
                try { } 
                finally
                { 
                    if (value == null)
                    {
                         safeWaitHandle = null;
                         waitHandle = InvalidHandle; 
                     }
                    else 
                    { 
                         safeWaitHandle = value;
                         waitHandle = safeWaitHandle.DangerousGetHandle(); 
                     }
                 }
             }
        } 

        // Assembly-private version that doesn't do a security check.  Reduces the 
        // number of link-time security checks when reading & writing to a file, 
        // and helps avoid a link time check while initializing security (If you
        // call a Serialization method that requires security before security 
        // has started up, the link time check will start up security, run
        // serialization code for some security attribute stuff, call into
        // FileStream, which will then call Sethandle, which requires a link time
        // security check.).  While security has fixed that problem, we still 
        // don't need to do a linktime check here.
        [System.Security.SecurityCritical]  // auto-generated 
        [ResourceExposure(ResourceScope.Machine)] 
        [ResourceConsumption(ResourceScope.Machine)]
        internal void SetHandleInternal(SafeWaitHandle handle) 
        {
            safeWaitHandle = handle;
            waitHandle = handle.DangerousGetHandle();
        } 

        public virtual bool WaitOne (int millisecondsTimeout, bool exitContext) 
        { 
            if (millisecondsTimeout < -1)
            { 
                throw new ArgumentOutOfRangeException("millisecondsTimeout", Environment.GetResourceString("ArgumentOutOfRange_NeedNonNegOrNegative1"));
            }
            Contract.EndContractBlock();
            return  WaitOne((long)millisecondsTimeout,exitContext); 
        }
 
        public virtual bool WaitOne (TimeSpan timeout, bool exitContext) 
        {
            long tm = (long)timeout.TotalMilliseconds; 
            if (-1 > tm || (long) Int32.MaxValue < tm)
            {
                throw new ArgumentOutOfRangeException("timeout", Environment.GetResourceString("ArgumentOutOfRange_NeedNonNegOrNegative1"));
            } 
            return WaitOne(tm,exitContext);
        } 
 
        public virtual bool WaitOne ()
        { 
            //Infinite Timeout
            return  WaitOne(-1,false);
        }
 
        public virtual bool WaitOne(int millisecondsTimeout)
        { 
            return WaitOne(millisecondsTimeout, false); 
        }
 
        public virtual bool WaitOne(TimeSpan timeout)
        {
            return WaitOne(timeout, false);
        } 

        [System.Security.SecuritySafeCritical]  // auto-generated 
        private bool WaitOne(long timeout, bool exitContext) 
        {
            return InternalWaitOne(safeWaitHandle, timeout, hasThreadAffinity, exitContext); 
        }

        [System.Security.SecurityCritical]  // auto-generated
        internal static bool InternalWaitOne(SafeHandle waitableSafeHandle, long millisecondsTimeout, bool hasThreadAffinity, bool exitContext) 
        {
            if (waitableSafeHandle == null) 
            { 
                throw new ObjectDisposedException(null, Environment.GetResourceString("ObjectDisposed_Generic"));
            } 
            Contract.EndContractBlock();
            int ret = WaitOneNative(waitableSafeHandle, (uint)millisecondsTimeout, hasThreadAffinity, exitContext);
            if (ret == WAIT_ABANDONED)
            { 
                ThrowAbandonedMutexException();
            } 
            return (ret != WaitTimeout); 
        }
 
        [System.Security.SecurityCritical]  // auto-generated
        [ResourceExposure(ResourceScope.None)]
        [MethodImplAttribute(MethodImplOptions.InternalCall)]
        private static extern int WaitOneNative(SafeHandle waitableSafeHandle, uint millisecondsTimeout, bool hasThreadAffinity, bool exitContext); 

        /*======================================================================= 
        ** Waits for signal from all the objects. 
        ** timeout indicates how long to wait before the method returns.
        ** This method will return either when all the object have been pulsed 
        ** or timeout milliseonds have elapsed.
        ** If exitContext is true then the synchronization domain for the context
        ** (if in a synchronized context) is exited before the wait and reacquired
        ========================================================================*/ 

        [System.Security.SecurityCritical]  // auto-generated 
        [ResourceExposure(ResourceScope.None)] 
        [MethodImplAttribute(MethodImplOptions.InternalCall)]
        [ReliabilityContract(Consistency.WillNotCorruptState, Cer.MayFail)] 
        private static extern int WaitMultiple(WaitHandle[] waitHandles, int millisecondsTimeout, bool exitContext, bool WaitAll);

        [System.Security.SecuritySafeCritical]  // auto-generated
        public static bool WaitAll(WaitHandle[] waitHandles, int millisecondsTimeout, bool exitContext) 
        {
            if (waitHandles == null) 
            { 
                throw new ArgumentNullException(Environment.GetResourceString("ArgumentNull_Waithandles"));
            } 
            if(waitHandles.Length == 0)
            {
                //
                // Some history: in CLR 1.0 and 1.1, we threw ArgumentException in this case, which was correct. 
                // Somehow, in 2.0, this became ArgumentNullException.  This was not fixed until Silverlight 2,
                // which went back to ArgumentException. 
                // 
                // Now we're in a bit of a bind.  Backward-compatibility requires us to keep throwing ArgumentException
                // in CoreCLR, and ArgumentNullException in the desktop CLR.  This is ugly, but so is breaking 
                // user code.
                //
#if FEATURE_CORECLR
                throw new ArgumentException(Environment.GetResourceString("Argument_EmptyWaithandleArray")); 
#else
                throw new ArgumentNullException(Environment.GetResourceString("Argument_EmptyWaithandleArray")); 
#endif 
            }
            if (waitHandles.Length > MAX_WAITHANDLES) 
            {
                throw new NotSupportedException(Environment.GetResourceString("NotSupported_MaxWaitHandles"));
            }
            if (-1 > millisecondsTimeout) 
            {
                throw new ArgumentOutOfRangeException("millisecondsTimeout", Environment.GetResourceString("ArgumentOutOfRange_NeedNonNegOrNegative1")); 
            } 
            Contract.EndContractBlock();
            WaitHandle[] internalWaitHandles = new WaitHandle[waitHandles.Length]; 
            for (int i = 0; i < waitHandles.Length; i ++)
            {
                WaitHandle waitHandle = waitHandles[i];
 
                if (waitHandle == null)
                    throw new ArgumentNullException(Environment.GetResourceString("ArgumentNull_ArrayElement")); 
 
#if FEATURE_REMOTING
                if (RemotingServices.IsTransparentProxy(waitHandle)) 
                    throw new InvalidOperationException(Environment.GetResourceString("InvalidOperation_WaitOnTransparentProxy"));
#endif

                internalWaitHandles[i] = waitHandle; 
            }
#if _DEBUG 
            // make sure we do not use waitHandles any more. 
            waitHandles = null;
#endif 
            int ret = WaitMultiple(internalWaitHandles, millisecondsTimeout, exitContext, true /* waitall*/ );
            if ((WAIT_ABANDONED <= ret) && (WAIT_ABANDONED+internalWaitHandles.Length > ret))
            {
                //In the case of WaitAll the OS will only provide the 
                //    information that mutex was abandoned.
                //    It won't tell us which one.  So we can't set the Index or provide access to the Mutex 
                ThrowAbandonedMutexException(); 
            }
 
            GC.KeepAlive(internalWaitHandles);
            return (ret != WaitTimeout);
        }
 
        public static bool WaitAll(
                                    WaitHandle[] waitHandles, 
                                    TimeSpan timeout, 
                                    bool exitContext)
        { 
            long tm = (long)timeout.TotalMilliseconds;
            if (-1 > tm || (long) Int32.MaxValue < tm)
            {
                throw new ArgumentOutOfRangeException("timeout", Environment.GetResourceString("ArgumentOutOfRange_NeedNonNegOrNegative1")); 
            }
            return WaitAll(waitHandles,(int)tm, exitContext); 
        } 

 
        /*=======================================================================
        ** Shorthand for WaitAll with timeout = Timeout.Infinite and exitContext = true
        ========================================================================*/
        [System.Security.SecuritySafeCritical]  // auto-generated 
        public static bool WaitAll(WaitHandle[] waitHandles)
        { 
            return WaitAll(waitHandles, Timeout.Infinite, true); 
        }
 
        [System.Security.SecuritySafeCritical]  // auto-generated
        public static bool WaitAll(WaitHandle[] waitHandles, int millisecondsTimeout)
        {
            return WaitAll(waitHandles, millisecondsTimeout, true); 
        }
 
        [System.Security.SecuritySafeCritical]  // auto-generated 
        public static bool WaitAll(WaitHandle[] waitHandles, TimeSpan timeout)
        { 
            return WaitAll(waitHandles, timeout, true);
        }

 
        /*=======================================================================
        ** Waits for notification from any of the objects. 
        ** timeout indicates how long to wait before the method returns. 
        ** This method will return either when either one of the object have been
        ** signalled or timeout milliseonds have elapsed. 
        ** If exitContext is true then the synchronization domain for the context
        ** (if in a synchronized context) is exited before the wait and reacquired
        ========================================================================*/
 
        [System.Security.SecuritySafeCritical]  // auto-generated
        [ReliabilityContract(Consistency.WillNotCorruptState, Cer.MayFail)] 
        public static int WaitAny(WaitHandle[] waitHandles, int millisecondsTimeout, bool exitContext) 
        {
            if (waitHandles==null) 
            {
                throw new ArgumentNullException(Environment.GetResourceString("ArgumentNull_Waithandles"));
            }
            if(waitHandles.Length == 0) 
            {
                throw new ArgumentException(Environment.GetResourceString("Argument_EmptyWaithandleArray")); 
            } 
            if (MAX_WAITHANDLES < waitHandles.Length)
            { 
                throw new NotSupportedException(Environment.GetResourceString("NotSupported_MaxWaitHandles"));
            }
            if (-1 > millisecondsTimeout)
            { 
                throw new ArgumentOutOfRangeException("millisecondsTimeout", Environment.GetResourceString("ArgumentOutOfRange_NeedNonNegOrNegative1"));
            } 
            Contract.EndContractBlock(); 
            WaitHandle[] internalWaitHandles = new WaitHandle[waitHandles.Length];
            for (int i = 0; i < waitHandles.Length; i ++) 
            {
                WaitHandle waitHandle = waitHandles[i];

                if (waitHandle == null) 
                    throw new ArgumentNullException(Environment.GetResourceString("ArgumentNull_ArrayElement"));
 
#if FEATURE_REMOTING 
                if (RemotingServices.IsTransparentProxy(waitHandle))
                    throw new InvalidOperationException(Environment.GetResourceString("InvalidOperation_WaitOnTransparentProxy")); 
#endif

                internalWaitHandles[i] = waitHandle;
            } 
#if _DEBUG
            // make sure we do not use waitHandles any more. 
            waitHandles = null; 
#endif
            int ret = WaitMultiple(internalWaitHandles, millisecondsTimeout, exitContext, false /* waitany*/ ); 

            if ((WAIT_ABANDONED <= ret) && (WAIT_ABANDONED+internalWaitHandles.Length > ret))
            {
                int mutexIndex = ret -WAIT_ABANDONED; 
                if(0 <= mutexIndex && mutexIndex < internalWaitHandles.Length)
                { 
                    ThrowAbandonedMutexException(mutexIndex,internalWaitHandles[mutexIndex]); 
                }
                else 
                {
                    ThrowAbandonedMutexException();
                }
            } 

            GC.KeepAlive(internalWaitHandles); 
                return ret; 
        }
 
        [ReliabilityContract(Consistency.WillNotCorruptState, Cer.MayFail)]
        public static int WaitAny(
                                    WaitHandle[] waitHandles,
                                    TimeSpan timeout, 
                                    bool exitContext)
        { 
            long tm = (long)timeout.TotalMilliseconds; 
            if (-1 > tm || (long) Int32.MaxValue < tm)
            { 
                throw new ArgumentOutOfRangeException("timeout", Environment.GetResourceString("ArgumentOutOfRange_NeedNonNegOrNegative1"));
            }
            return WaitAny(waitHandles,(int)tm, exitContext);
        } 
        [ReliabilityContract(Consistency.WillNotCorruptState, Cer.MayFail)]
        public static int WaitAny(WaitHandle[] waitHandles, TimeSpan timeout) 
        { 
            return WaitAny(waitHandles, timeout, true);
        } 


        /*========================================================================
        ** Shorthand for WaitAny with timeout = Timeout.Infinite and exitContext = true 
        ========================================================================*/
        [ReliabilityContract(Consistency.WillNotCorruptState, Cer.MayFail)] 
        public static int WaitAny(WaitHandle[] waitHandles) 
        {
            return WaitAny(waitHandles, Timeout.Infinite, true); 
        }

        [ReliabilityContract(Consistency.WillNotCorruptState, Cer.MayFail)]
        public static int WaitAny(WaitHandle[] waitHandles, int millisecondsTimeout) 
        {
            return WaitAny(waitHandles, millisecondsTimeout, true); 
        } 
#if !FEATURE_PAL
        /*================================================= 
        ==
        ==  SignalAndWait
        ==
        ==================================================*/ 

        [System.Security.SecurityCritical]  // auto-generated 
        [ResourceExposure(ResourceScope.None)] 
        [MethodImplAttribute(MethodImplOptions.InternalCall)]
        private static extern int SignalAndWaitOne(SafeWaitHandle waitHandleToSignal,SafeWaitHandle waitHandleToWaitOn, int millisecondsTimeout, 
                                            bool hasThreadAffinity,  bool exitContext);

        public static bool SignalAndWait(
                                        WaitHandle toSignal, 
                                        WaitHandle toWaitOn)
        { 
            return SignalAndWait(toSignal,toWaitOn,-1,false); 
        }
 
        public static bool SignalAndWait(
                                        WaitHandle toSignal,
                                        WaitHandle toWaitOn,
                                        TimeSpan timeout, 
                                        bool exitContext)
        { 
            long tm = (long)timeout.TotalMilliseconds; 
            if (-1 > tm || (long) Int32.MaxValue < tm)
            { 
                throw new ArgumentOutOfRangeException("timeout", Environment.GetResourceString("ArgumentOutOfRange_NeedNonNegOrNegative1"));
            }
            return SignalAndWait(toSignal,toWaitOn,(int)tm,exitContext);
        } 

        [System.Security.SecuritySafeCritical]  // auto-generated 
        public static bool SignalAndWait( 
                                        WaitHandle toSignal,
                                        WaitHandle toWaitOn, 
                                        int millisecondsTimeout,
                                        bool exitContext)
        {
            if(null == toSignal) 
            {
                throw new ArgumentNullException("toSignal"); 
            } 
            if(null == toWaitOn)
            { 
                throw new ArgumentNullException("toWaitOn");
            }
            if (-1 > millisecondsTimeout)
            { 
                throw new ArgumentOutOfRangeException("millisecondsTimeout", Environment.GetResourceString("ArgumentOutOfRange_NeedNonNegOrNegative1"));
            } 
            Contract.EndContractBlock(); 

            int ret = SignalAndWaitOne(toSignal.safeWaitHandle,toWaitOn.safeWaitHandle,millisecondsTimeout, 
                                toWaitOn.hasThreadAffinity,exitContext);

            if(WAIT_FAILED != ret  && toSignal.hasThreadAffinity)
            { 
                Thread.EndCriticalRegion();
                Thread.EndThreadAffinity(); 
            } 

            if(WAIT_ABANDONED == ret) 
            {
                ThrowAbandonedMutexException();
            }
 
            if(ERROR_TOO_MANY_POSTS == ret)
            { 
                throw new InvalidOperationException(Environment.GetResourceString("Threading.WaitHandleTooManyPosts")); 
            }
 
            //Object was signaled
            if(WAIT_OBJECT_0 == ret)
            {
                return true; 
            }
 
            //Timeout 
            return false;
        } 
#endif

        private static void ThrowAbandonedMutexException()
        { 
#if !FEATURE_CORECLR
            throw new AbandonedMutexException(); 
#else 
            throw new Exception(Environment.GetResourceString("Threading.AbandonedMutexException"));
#endif 
        }

        private static void ThrowAbandonedMutexException(int location, WaitHandle handle)
        { 
#if !FEATURE_CORECLR
            throw new AbandonedMutexException(location, handle); 
#else 
            throw new Exception(Environment.GetResourceString("Threading.AbandonedMutexException"));
#endif 
        }

        public virtual void Close()
        { 
            Dispose(true);
            GC.SuppressFinalize(this); 
        } 

        [System.Security.SecuritySafeCritical]  // auto-generated 
        protected virtual void Dispose(bool explicitDisposing)
        {
            if (safeWaitHandle != null)
            { 
                safeWaitHandle.Close();
            } 
        } 

#if FEATURE_CORECLR 
        void IDisposable.Dispose()
#if false // ugly hack to fix syntax for TrimSrc parser, which ignores #if directives
        {
        } 
#endif
#else 
        public void Dispose() 
#endif
        { 
            Dispose(true);
            GC.SuppressFinalize(this);
        }
    } 
}

// File provided for Reference Use Only by Microsoft Corporation (c) 2007.

Link Menu

Network programming in C#, Network Programming in VB.NET, Network Programming in .NET
This book is available now!
Buy at Amazon US or
Buy at Amazon UK