//
// System.ValueType.cs
//
// Author:
// Miguel de Icaza (miguel@ximian.com)
// Gonzalo Paniagua Javier (gonzalo@ximian.com)
//
// (C) Ximian, Inc. http://www.ximian.com
// (C) 2003 Novell, Inc. http://www.novell.com
//
//
// Copyright (C) 2004 Novell, Inc (http://www.novell.com)
//
// Permission is hereby granted, free of charge, to any person obtaining
// a copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to
// permit persons to whom the Software is furnished to do so, subject to
// the following conditions:
//
// The above copyright notice and this permission notice shall be
// included in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
// EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
// NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
// LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
// OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//
//
// Copyright (c) Microsoft. All rights reserved.
// Licensed under the MIT license. See LICENSE file in the project root for full license information.
//
// Files:
// - mscorlib/system/valuetype.cs
//
using System.Reflection;
using System.Runtime.CompilerServices;
using System.Runtime.InteropServices;
using System.Threading;
namespace System
{
[Serializable]
[ComVisible (true)]
public abstract class ValueType
{
protected ValueType ()
{
}
[MethodImplAttribute (MethodImplOptions.InternalCall)]
private extern static bool InternalEquals (object o1, object o2, out object[] fields);
// This is also used by RuntimeHelpers
internal static bool DefaultEquals (object o1, object o2)
{
if (o1 == null && o2 == null)
return true;
if (o1 == null || o2 == null)
return false;
RuntimeType o1_type = (RuntimeType) o1.GetType ();
RuntimeType o2_type = (RuntimeType) o2.GetType ();
if (o1_type != o2_type)
return false;
object[] fields;
bool res = InternalEquals (o1, o2, out fields);
if (fields == null)
return res;
for (int i = 0; i < fields.Length; i += 2) {
object meVal = fields [i];
object youVal = fields [i + 1];
if (meVal == null) {
if (youVal == null)
continue;
return false;
}
if (!meVal.Equals (youVal))
return false;
}
return true;
}
//
// True if this instance and o represent the same type
// and have the same value.
//
public override bool Equals (object obj)
{
return DefaultEquals (this, obj);
}
[MethodImplAttribute (MethodImplOptions.InternalCall)]
internal extern static int InternalGetHashCode (object o, out object[] fields);
//
// Gets a hashcode for this value type using the
// bits in the structure
//
public override int GetHashCode ()
{
object[] fields;
int result = InternalGetHashCode (this, out fields);
if (fields != null)
for (int i = 0; i < fields.Length; ++i)
if (fields [i] != null)
result ^= fields [i].GetHashCode ();
return result;
}
static int hash_code_of_ptr_seed = 0;
internal static int GetHashCodeOfPtr (IntPtr ptr)
{
int hash_code = (int) ptr;
int seed = hash_code_of_ptr_seed;
if (seed == 0) {
/* We use the first non-0 pointer as the seed, all hashcodes will be
* based off that. This is to make sure that we only reveal relative
* memory addresses and never absolute ones. */
seed = hash_code;
Interlocked.CompareExchange (ref hash_code_of_ptr_seed, seed, 0);
seed = hash_code_of_ptr_seed;
}
return hash_code - seed;
}
//
// Stringified representation of this ValueType.
// Must be overriden for better results, by default
// it just returns the Type name.
//
public override string ToString ()
{
return GetType ().FullName;
}
}
}