Imported Upstream version 4.6.0.125

Former-commit-id: a2155e9bd80020e49e72e86c44da02a8ac0e57a4

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

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+// ==++==
+// 
+//   Copyright (c) Microsoft Corporation.  All rights reserved.
+// 
+// ==--==
+/*============================================================
+**
+** Class:  SafeProcessHandle 
+**
+** A wrapper for a process handle
+**
+** 
+===========================================================*/
+
+using System;
+using System.Security;
+using System.Diagnostics;
+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 {
+    [SuppressUnmanagedCodeSecurityAttribute]
+    public sealed class SafeProcessHandle : SafeHandleZeroOrMinusOneIsInvalid
+    { 
+        internal static SafeProcessHandle InvalidHandle = new SafeProcessHandle(IntPtr.Zero); 
+    
+        // Note that OpenProcess returns 0 on failure
+
+        internal SafeProcessHandle() : base(true) {}
+
+        internal SafeProcessHandle(IntPtr handle) : base(true) {
+            SetHandle(handle);
+        }
+        
+        [SecurityPermission(SecurityAction.LinkDemand, UnmanagedCode = true)]
+        public SafeProcessHandle(IntPtr existingHandle, bool ownsHandle) : base(ownsHandle) {
+            SetHandle(existingHandle);
+        }
+
+#if !MONO
+        [DllImport(ExternDll.Kernel32, CharSet=System.Runtime.InteropServices.CharSet.Auto, SetLastError=true)]
+        [ResourceExposure(ResourceScope.Machine)]
+        internal static extern SafeProcessHandle OpenProcess(int access, bool inherit, int processId);
+#endif
+        
+        internal void InitialSetHandle(IntPtr h){
+            Debug.Assert(base.IsInvalid, "Safe handle should only be set once");
+            base.handle = h;
+        }
+        
+        override protected bool ReleaseHandle()
+        {
+#if !MONO
+            return SafeNativeMethods.CloseHandle(handle);
+#else
+            return NativeMethods.CloseProcess (handle);
+#endif
+        }
+
+    }
+}
+
+
+
+