src/System.Private.CoreLib/src/System/Threading/Semaphore.Unix.cs


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// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.

using Microsoft.Win32.SafeHandles;
using System.Diagnostics;
using System.IO;
using System.Runtime.InteropServices;

namespace System.Threading
{
    public sealed partial class Semaphore
    {
        private void CreateSemaphoreCore(int initialCount, int maximumCount, string name, out bool createdNew)
        {
            if (name != null)
            {
                throw new PlatformNotSupportedException(SR.PlatformNotSupported_NamedSynchronizationPrimitives);
            }

            SafeWaitHandle = WaitSubsystem.NewSemaphore(initialCount, maximumCount);
            createdNew = true;
        }

        private static OpenExistingResult OpenExistingWorker(string name, out Semaphore result)
        {
            throw new PlatformNotSupportedException(SR.PlatformNotSupported_NamedSynchronizationPrimitives);
        }

        private int ReleaseCore(int releaseCount)
        {
            // The field value is modifiable via the public <see cref="WaitHandle.SafeWaitHandle"/> property, save it locally
            // to ensure that one instance is used in all places in this method
            SafeWaitHandle waitHandle = _waitHandle;
            if (waitHandle == null)
            {
                ThrowInvalidHandleException();
            }

            waitHandle.DangerousAddRef();
            try
            {
                return WaitSubsystem.ReleaseSemaphore(waitHandle.DangerousGetHandle(), releaseCount);
            }
            finally
            {
                waitHandle.DangerousRelease();
            }
        }
    }
}