Add os::Semaphore

src/LibHac/Os/Impl/InternalConditionVariable-os.net.cs

@@ -1,13 +1,15 @@
-using System.Threading;
+using System;
+using System.Threading;
 using LibHac.Diag;
 
 namespace LibHac.Os.Impl;
 
-internal struct InternalConditionVariableImpl
+internal struct InternalConditionVariableImpl : IDisposable
 {
     private object _obj;
 
     public InternalConditionVariableImpl() => _obj = new object();
+    public void Dispose() { }
     public void Initialize() => _obj = new object();
 
     public void Signal()

src/LibHac/Os/Impl/InternalConditionVariable.cs

@@ -1,6 +1,8 @@
-namespace LibHac.Os.Impl;
+using System;
 
-internal struct InternalConditionVariable
+namespace LibHac.Os.Impl;
+
+internal struct InternalConditionVariable : IDisposable
 {
     private InternalConditionVariableImpl _impl;
 
@@ -9,6 +11,11 @@ internal struct InternalConditionVariable
         _impl = new InternalConditionVariableImpl();
     }
 
+    public void Dispose()
+    {
+        _impl.Dispose();
+    }
+
     public void Initialize() => _impl.Initialize();
     public void Signal() => _impl.Signal();
     public void Broadcast() => _impl.Broadcast();

src/LibHac/Os/Impl/MultiWaitHolderImpl.cs

@@ -6,9 +6,8 @@ public class MultiWaitHolderImpl
 
     public MultiWaitHolderBase HolderBase => _holder;
     public MultiWaitHolderOfNativeHandle HolderOfNativeHandle => (MultiWaitHolderOfNativeHandle)_holder;
+    public MultiWaitHolderOfSemaphore HolderOfSemaphore => (MultiWaitHolderOfSemaphore)_holder;
 
-    public MultiWaitHolderImpl(MultiWaitHolderOfNativeHandle holder)
-    {
-        _holder = holder;
-    }
+    public MultiWaitHolderImpl(MultiWaitHolderOfNativeHandle holder) => _holder = holder;
+    public MultiWaitHolderImpl(MultiWaitHolderOfSemaphore holder) => _holder = holder;
 }

src/LibHac/Os/Impl/MultipleWaitHolderOfSemaphore.cs

@@ -0,0 +1,38 @@
+namespace LibHac.Os.Impl;
+
+public class MultiWaitHolderOfSemaphore : MultiWaitHolderOfUserWaitObject
+{
+    private Semaphore _semaphore;
+
+    public MultiWaitHolderOfSemaphore(Semaphore semaphore)
+    {
+        _semaphore = semaphore;
+    }
+
+    public override TriBool IsSignaled()
+    {
+        using ScopedLock<InternalCriticalSection> lk = ScopedLock.Lock(ref _semaphore.GetBase().CsSemaphore);
+
+        return IsSignaledUnsafe();
+    }
+
+    public override TriBool AddToObjectList()
+    {
+        using ScopedLock<InternalCriticalSection> lk = ScopedLock.Lock(ref _semaphore.GetBase().CsSemaphore);
+
+        _semaphore.GetBase().WaitList.PushBackToList(this);
+        return IsSignaledUnsafe();
+    }
+
+    public override void RemoveFromObjectList()
+    {
+        using ScopedLock<InternalCriticalSection> lk = ScopedLock.Lock(ref _semaphore.GetBase().CsSemaphore);
+
+        _semaphore.GetBase().WaitList.EraseFromList(this);
+    }
+
+    private TriBool IsSignaledUnsafe()
+    {
+        return _semaphore.GetBase().Count > 0 ? TriBool.True : TriBool.False;
+    }
+}

src/LibHac/Os/Semaphore.cs

@@ -0,0 +1,206 @@
+using System;
+using LibHac.Diag;
+using LibHac.Os.Impl;
+
+namespace LibHac.Os;
+
+public class Semaphore : IDisposable
+{
+    private SemaphoreType _semaphore;
+
+    public Semaphore(OsState os, int initialCount, int maxCount) =>
+        _semaphore = new SemaphoreType(os, initialCount, maxCount);
+
+    public void Dispose() => _semaphore.Dispose();
+    public void Acquire() => _semaphore.Acquire();
+    public bool TryAcquire() => _semaphore.TryAcquire();
+    public bool TimedAcquire(TimeSpan timeout) => _semaphore.TimedAcquire(timeout);
+    public void Release() => _semaphore.Release();
+    public void Release(int count) => _semaphore.Release(count);
+    public int GetCurrentCount() => _semaphore.GetCurrentCount();
+    public ref SemaphoreType GetBase() => ref _semaphore;
+}
+
+public struct SemaphoreType : IDisposable
+{
+    public enum State : byte
+    {
+        NotInitialized = 0,
+        Initialized = 1
+    }
+
+    internal MultiWaitObjectList WaitList;
+    internal State CurrentState;
+    internal int Count;
+    internal int MaxCount;
+
+    internal InternalCriticalSection CsSemaphore;
+    internal InternalConditionVariable CvNotZero;
+
+    private readonly OsState _os;
+
+    public SemaphoreType(OsState os, int initialCount, int maxCount)
+    {
+        Assert.SdkRequires(maxCount >= 1);
+        Assert.SdkRequires(initialCount >= 0 && initialCount <= maxCount);
+
+        CsSemaphore = new InternalCriticalSection();
+        CvNotZero = new InternalConditionVariable();
+
+        WaitList = new MultiWaitObjectList();
+
+        Count = initialCount;
+        MaxCount = maxCount;
+        CurrentState = State.Initialized;
+        _os = os;
+    }
+
+    public void Dispose()
+    {
+        Assert.SdkRequires(CurrentState == State.Initialized);
+        Assert.SdkRequires(WaitList.IsEmpty());
+
+        CurrentState = State.NotInitialized;
+
+        CsSemaphore.Dispose();
+        CvNotZero.Dispose();
+    }
+
+    public void Acquire()
+    {
+        Assert.SdkRequires(CurrentState == State.Initialized);
+
+        using ScopedLock<InternalCriticalSection> lk = ScopedLock.Lock(ref CsSemaphore);
+
+        while (Count == 0)
+        {
+            CvNotZero.Wait(ref CsSemaphore);
+        }
+
+        Count--;
+    }
+
+    public bool TryAcquire()
+    {
+        Assert.SdkRequires(CurrentState == State.Initialized);
+
+        using ScopedLock<InternalCriticalSection> lk = ScopedLock.Lock(ref CsSemaphore);
+
+        if (Count == 0)
+        {
+            return false;
+        }
+
+        Count--;
+
+        return true;
+    }
+
+    public bool TimedAcquire(TimeSpan timeout)
+    {
+        Assert.SdkRequires(CurrentState == State.Initialized);
+        Assert.SdkRequires(timeout.GetNanoSeconds() >= 0);
+
+        var timeoutHelper = new TimeoutHelper(_os, timeout);
+        using ScopedLock<InternalCriticalSection> lk = ScopedLock.Lock(ref CsSemaphore);
+
+        while (Count == 0)
+        {
+            if (timeoutHelper.TimedOut())
+                return false;
+
+            CvNotZero.TimedWait(ref CsSemaphore, in timeoutHelper);
+        }
+
+        Count--;
+
+        return true;
+    }
+
+    public void Release()
+    {
+        Assert.SdkRequires(CurrentState == State.Initialized);
+
+        using ScopedLock<InternalCriticalSection> lk = ScopedLock.Lock(ref CsSemaphore);
+
+        Assert.SdkAssert(Count + 1 <= MaxCount);
+
+        Count++;
+
+        CvNotZero.Signal();
+        WaitList.WakeupAllMultiWaitThreadsUnsafe();
+    }
+
+    public void Release(int count)
+    {
+        Assert.SdkRequires(CurrentState == State.Initialized);
+        Assert.SdkRequires(Count >= 1);
+
+        using ScopedLock<InternalCriticalSection> lk = ScopedLock.Lock(ref CsSemaphore);
+
+        Assert.SdkAssert(Count + count <= MaxCount);
+
+        Count += count;
+
+        CvNotZero.Broadcast();
+        WaitList.WakeupAllMultiWaitThreadsUnsafe();
+    }
+
+    public readonly int GetCurrentCount()
+    {
+        Assert.SdkRequires(CurrentState == State.Initialized);
+
+        return Count;
+    }
+}
+
+public static class SemaphoreApi
+{
+    public static void InitializeSemaphore(this OsState os, out SemaphoreType semaphore, int initialCount, int maxCount)
+    {
+        semaphore = new SemaphoreType(os, initialCount, maxCount);
+    }
+
+    public static void FinalizeSemaphore(this OsState os, ref SemaphoreType semaphore)
+    {
+        semaphore.Dispose();
+    }
+
+    public static void AcquireSemaphore(this OsState os, ref SemaphoreType semaphore)
+    {
+        semaphore.Acquire();
+    }
+
+    public static bool TryAcquireSemaphore(this OsState os, ref SemaphoreType semaphore)
+    {
+        return semaphore.TryAcquire();
+    }
+
+    public static bool TimedAcquireSemaphore(this OsState os, ref SemaphoreType semaphore, TimeSpan timeout)
+    {
+        return semaphore.TimedAcquire(timeout);
+    }
+
+    public static void ReleaseSemaphore(this OsState os, ref SemaphoreType semaphore)
+    {
+        semaphore.Release();
+    }
+
+    public static void ReleaseSemaphore(this OsState os, ref SemaphoreType semaphore, int count)
+    {
+        semaphore.Release(count);
+    }
+
+    public static int GetCurrentSemaphoreCount(this OsState os, in SemaphoreType semaphore)
+    {
+        return semaphore.GetCurrentCount();
+    }
+
+    public static void InitializeMultiWaitHolder(this OsState os, MultiWaitHolderType holder, Semaphore semaphore)
+    {
+        Assert.SdkRequires(semaphore.GetBase().CurrentState == SemaphoreType.State.Initialized);
+
+        holder.Impl = new MultiWaitHolderImpl(new MultiWaitHolderOfSemaphore(semaphore));
+        holder.UserData = null;
+    }
+}