1 files changed, 83 insertions, 0 deletions
diff --git a/src/Ryujinx.HLE/HOS/Kernel/Process/KContextIdManager.cs b/src/Ryujinx.HLE/HOS/Kernel/Process/KContextIdManager.cs
new file mode 100644
index 00000000..104fe578
--- /dev/null
+++ b/src/Ryujinx.HLE/HOS/Kernel/Process/KContextIdManager.cs
@@ -0,0 +1,83 @@
+using System;
+using System.Numerics;
+
+namespace Ryujinx.HLE.HOS.Kernel.Process
+{
+    class KContextIdManager
+    {
+        private const int IdMasksCount = 8;
+
+        private int[] _idMasks;
+
+        private int _nextFreeBitHint;
+
+        public KContextIdManager()
+        {
+            _idMasks = new int[IdMasksCount];
+        }
+
+        public int GetId()
+        {
+            lock (_idMasks)
+            {
+                int id = 0;
+
+                if (!TestBit(_nextFreeBitHint))
+                {
+                    id = _nextFreeBitHint;
+                }
+                else
+                {
+                    for (int index = 0; index < IdMasksCount; index++)
+                    {
+                        int mask = _idMasks[index];
+
+                        int firstFreeBit = BitOperations.LeadingZeroCount((uint)((mask + 1) & ~mask));
+
+                        if (firstFreeBit < 32)
+                        {
+                            int baseBit = index * 32 + 31;
+
+                            id = baseBit - firstFreeBit;
+
+                            break;
+                        }
+                        else if (index == IdMasksCount - 1)
+                        {
+                            throw new InvalidOperationException("Maximum number of Ids reached!");
+                        }
+                    }
+                }
+
+                _nextFreeBitHint = id + 1;
+
+                SetBit(id);
+
+                return id;
+            }
+        }
+
+        public void PutId(int id)
+        {
+            lock (_idMasks)
+            {
+                ClearBit(id);
+            }
+        }
+
+        private bool TestBit(int bit)
+        {
+            return (_idMasks[_nextFreeBitHint / 32] & (1 << (_nextFreeBitHint & 31))) != 0;
+        }
+
+        private void SetBit(int bit)
+        {
+            _idMasks[_nextFreeBitHint / 32] |= (1 << (_nextFreeBitHint & 31));
+        }
+
+        private void ClearBit(int bit)
+        {
+            _idMasks[_nextFreeBitHint / 32] &= ~(1 << (_nextFreeBitHint & 31));
+        }
+    }
+}
+\ No newline at end of file