mcs/class/referencesource/mscorlib/system/reflection/pointer.cs

   1 // ==++==
   2 //
   3 //   Copyright (c) Microsoft Corporation.  All rights reserved.
   4 //
   5 // ==--==
   6 ////////////////////////////////////////////////////////////////////////////////
   7 //
   8 // This is a wrapper class for Pointers
   9 //
  10 // <OWNER>Microsoft</OWNER>
  11 //
  12 //
  13 //
  14 //
  15 namespace System.Reflection {
  16     using System;
  17     using CultureInfo = System.Globalization.CultureInfo;
  18     using System.Runtime.Serialization;
  19     using System.Security;
  20     using System.Diagnostics.Contracts;
  21
  22     [CLSCompliant(false)]
  23     [Serializable]
  24     [System.Runtime.InteropServices.ComVisible(true)]
  25     public sealed class Pointer: ISerializable {
  26         [SecurityCritical]
  27         unsafe private void* _ptr;
  28         private RuntimeType _ptrType;
  29
  30         private Pointer() {}
  31
  32         [System.Security.SecurityCritical]  // auto-generated
  33         private unsafe Pointer(SerializationInfo info, StreamingContext context)
  34         {
  35             _ptr = ((IntPtr)(info.GetValue("_ptr", typeof(IntPtr)))).ToPointer();
  36             _ptrType = (RuntimeType)info.GetValue("_ptrType", typeof(RuntimeType));
  37         }
  38
  39         // This method will box an pointer.  We save both the
  40         //    value and the type so we can access it from the native code
  41         //    during an Invoke.
  42         [System.Security.SecurityCritical]  // auto-generated
  43         public static unsafe Object Box(void *ptr,Type type) {
  44             if (type == null)
  45                 throw new ArgumentNullException("type");
  46             if (!type.IsPointer)
  47                 throw new ArgumentException(Environment.GetResourceString("Arg_MustBePointer"),"ptr");
  48             Contract.EndContractBlock();
  49
  50             RuntimeType rt = type as RuntimeType;
  51             if (rt == null)
  52                 throw new ArgumentException(Environment.GetResourceString("Arg_MustBePointer"), "ptr");
  53
  54             Pointer x = new Pointer();
  55             x._ptr = ptr;
  56             x._ptrType = rt;
  57             return x;
  58         }
  59
  60         // Returned the stored pointer.
  61         [System.Security.SecurityCritical]  // auto-generated
  62         public static unsafe void* Unbox(Object ptr) {
  63             if (!(ptr is Pointer))
  64                 throw new ArgumentException(Environment.GetResourceString("Arg_MustBePointer"),"ptr");
  65             return ((Pointer)ptr)._ptr;
  66         }
  67
  68         internal RuntimeType GetPointerType() {
  69             return _ptrType;
  70         }
  71
  72         [System.Security.SecurityCritical]  // auto-generated
  73         internal unsafe Object GetPointerValue() {
  74             return (IntPtr)_ptr;
  75         }
  76
  77 #if FEATURE_SERIALIZATION
  78         [System.Security.SecurityCritical]
  79         unsafe void ISerializable.GetObjectData(SerializationInfo info, StreamingContext context) {
  80             info.AddValue("_ptr", new IntPtr(_ptr));
  81             info.AddValue("_ptrType", _ptrType);
  82         }
  83 #endif
  84     }
  85 }