Imported Upstream version 4.6.0.125

Former-commit-id: a2155e9bd80020e49e72e86c44da02a8ac0e57a4

mcs/class/referencesource/System/compmod/microsoft/win32/safehandles/SafeLibraryHandle.cs

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+// ==++==
+// 
+//   Copyright (c) Microsoft Corporation.  All rights reserved.
+// 
+// ==--==
+/*============================================================
+**
+** Class:  SafeLibraryHandle 
+**
+** <EMAIL>Author: David Gutierrez ([....]) </EMAIL>
+**
+** A wrapper for a library handles
+**
+** Date:  July 8, 2002
+** 
+===========================================================*/
+
+using System;
+using System.Security;
+using System.Security.Permissions;
+using System.Runtime.InteropServices;
+using System.Runtime.CompilerServices;
+using Microsoft.Win32;
+using Microsoft.Win32.SafeHandles;
+using System.Runtime.ConstrainedExecution;
+using System.Runtime.Versioning;
+
+namespace Microsoft.Win32.SafeHandles {
+    [HostProtectionAttribute(MayLeakOnAbort = true)]
+    [SuppressUnmanagedCodeSecurityAttribute]
+    internal sealed class SafeLibraryHandle : SafeHandleZeroOrMinusOneIsInvalid
+    {
+        // Note that LoadLibraryEx returns 0 on failure
+
+        internal SafeLibraryHandle() : base(true) {}
+        
+        [DllImport(ExternDll.Kernel32, CharSet=System.Runtime.InteropServices.CharSet.Unicode, SetLastError=true)]
+        [ResourceExposure(ResourceScope.Machine)]
+        internal static extern SafeLibraryHandle LoadLibraryEx(string libFilename, IntPtr reserved, int flags);        
+                
+        [DllImport(ExternDll.Kernel32, CharSet=System.Runtime.InteropServices.CharSet.Unicode)]
+        [ResourceExposure(ResourceScope.None)]
+#if !FEATURE_WINDOWSPHONE
+        [ReliabilityContract(Consistency.WillNotCorruptState, Cer.Success)]
+#endif // !FEATURE_WINDOWSPHONE
+        private static extern bool FreeLibrary(IntPtr hModule);     
+
+        override protected bool ReleaseHandle()
+        {
+            return FreeLibrary(handle);
+        }
+
+    }
+}
+
+
+
+