1 files changed, 122 insertions, 0 deletions
diff --git a/Ryujinx.Core/OsHle/Mutex.cs b/Ryujinx.Core/OsHle/Mutex.cs
new file mode 100644
index 00000000..c95ed771
--- /dev/null
+++ b/Ryujinx.Core/OsHle/Mutex.cs
@@ -0,0 +1,122 @@
+using Ryujinx.Core.OsHle.Handles;
+using System.Collections.Concurrent;
+using System.Threading;
+
+namespace Ryujinx.Core.OsHle
+{
+    public class Mutex
+    {
+        private const int MutexHasListenersMask = 0x40000000;
+
+        private Process Process;
+
+        private long MutexAddress;
+
+        private bool OwnsMutexValue;
+
+        private object EnterWaitLock;
+
+        private ConcurrentQueue<HThread> WaitingThreads;
+
+        public Mutex(Process Process, long MutexAddress, int OwnerThreadHandle)
+        {
+            this.Process      = Process;
+            this.MutexAddress = MutexAddress;
+
+            //Process.Memory.WriteInt32(MutexAddress, OwnerThreadHandle);
+
+            EnterWaitLock = new object();
+
+            WaitingThreads = new ConcurrentQueue<HThread>();
+        }
+
+        public void WaitForLock(HThread RequestingThread, int RequestingThreadHandle)
+        {
+            AcquireMutexValue();
+
+            lock (EnterWaitLock)
+            {
+                int CurrentThreadHandle = Process.Memory.ReadInt32(MutexAddress) & ~MutexHasListenersMask;
+
+                if (CurrentThreadHandle == RequestingThreadHandle ||
+                    CurrentThreadHandle == 0)
+                {
+                    return;
+                }
+
+                Process.Memory.WriteInt32(MutexAddress, CurrentThreadHandle | MutexHasListenersMask);
+
+                ReleaseMutexValue();
+
+                WaitingThreads.Enqueue(RequestingThread);
+            }
+
+            Process.Scheduler.WaitForSignal(RequestingThread);
+        }
+
+        public void GiveUpLock(int ThreadHandle)
+        {
+            AcquireMutexValue();
+
+            lock (EnterWaitLock)
+            {
+                int CurrentThread = Process.Memory.ReadInt32(MutexAddress) & ~MutexHasListenersMask;
+
+                if (CurrentThread == ThreadHandle)
+                {
+                    Unlock();
+                }
+            }
+
+            ReleaseMutexValue();
+        }
+
+        public void Unlock()
+        {
+            AcquireMutexValue();
+
+            lock (EnterWaitLock)
+            {
+                int HasListeners = WaitingThreads.Count > 1 ? MutexHasListenersMask : 0;
+
+                Process.Memory.WriteInt32(MutexAddress, HasListeners);
+
+                ReleaseMutexValue();
+
+                HThread[] UnlockedThreads = new HThread[WaitingThreads.Count];
+
+                int Index = 0;
+
+                while (WaitingThreads.TryDequeue(out HThread Thread))
+                {
+                    UnlockedThreads[Index++] = Thread;
+                }
+
+                Process.Scheduler.Signal(UnlockedThreads);
+            }
+        }
+
+        private void AcquireMutexValue()
+        {
+            if (!OwnsMutexValue)
+            {
+                while (!Process.Memory.AcquireAddress(MutexAddress))
+                {
+                    Thread.Yield();
+                }
+
+                OwnsMutexValue = true;
+            }
+        }
+
+        private void ReleaseMutexValue()
+        {
+            if (OwnsMutexValue)
+            {
+                OwnsMutexValue = false;
+
+                Process.Memory.ReleaseAddress(MutexAddress);
+            }
+        }
+    }
+}
+\ No newline at end of file