checkpoint

Alpm/SafeCachePackageHandle.cs

@@ -0,0 +1,46 @@
+using System;
+using System.Runtime.CompilerServices;
+using System.Runtime.ConstrainedExecution;
+
+namespace Foodsoft.Alpm
+{
+    internal sealed class SafeCachePackageHandle : SafePackageHandle
+    {
+        internal SafeAlpmHandle SafeAlpmHandle => SafeDatabaseHandle.SafeAlpmHandle;
+        internal SafeDatabaseHandle SafeDatabaseHandle { get; } = null!;
+
+        [ReliabilityContract(Consistency.WillNotCorruptState, Cer.MayFail)]
+        [PrePrepareMethod]
+        internal SafeCachePackageHandle(IntPtr ptr, SafeDatabaseHandle dbHandle)
+            : base()
+        {
+            var success = false;
+
+            RuntimeHelpers.PrepareConstrainedRegions();
+            try { }
+            finally
+            {
+                dbHandle.DangerousAddRef(ref success);
+                if (success)
+                {
+                    SafeDatabaseHandle = dbHandle;
+                    handle = ptr;
+                }
+            }
+
+            if (!success) throw new ObjectDisposedException(GetType().FullName);
+        }
+
+        protected override bool ReleaseHandle()
+        {
+            SafeDatabaseHandle.DangerousRelease();
+            return true;
+        }
+
+        public override bool IsInvalid
+        {
+            [ReliabilityContract(Consistency.WillNotCorruptState, Cer.Success), PrePrepareMethod]
+            get => handle == IntPtr.Zero;
+        }
+    }
+}