checkpoint

Alpm/SafeListHandle`1.cs

@@ -0,0 +1,52 @@
+using System;
+using System.Runtime.CompilerServices;
+using System.Runtime.ConstrainedExecution;
+using System.Runtime.InteropServices;
+
+namespace Foodsoft.Alpm
+{
+    internal sealed class SafeListHandle<TParent> : SafeHandle where TParent: SafeHandle
+    {
+        internal TParent ParentHandle
+        {
+            [ReliabilityContract(Consistency.WillNotCorruptState, Cer.Success)]
+            [PrePrepareMethod]
+            get;
+        } = null!;
+
+        [ReliabilityContract(Consistency.WillNotCorruptState, Cer.MayFail)]
+        [PrePrepareMethod]
+        internal SafeListHandle(IntPtr listPtr, TParent parentHandle)
+            : base(IntPtr.Zero, true)
+        {
+            var success = false;
+            RuntimeHelpers.PrepareConstrainedRegions();
+            try { }
+            finally
+            {
+                parentHandle.DangerousAddRef(ref success);
+                if (success)
+                {
+                    ParentHandle = parentHandle;
+                    handle = listPtr;
+                }
+
+            }
+            if (!success)
+                throw new ObjectDisposedException(GetType().FullName);
+        }
+
+        [ReliabilityContract(Consistency.WillNotCorruptState, Cer.Success), PrePrepareMethod]
+        protected override bool ReleaseHandle()
+        {
+            ParentHandle.DangerousRelease();
+            return true;
+        }
+
+        public override bool IsInvalid
+        {
+            [ReliabilityContract(Consistency.WillNotCorruptState, Cer.Success), PrePrepareMethod]
+            get => ParentHandle.IsInvalid;
+        }
+    }
+}