// 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
{
+ /*
+ * Caution: Fields added to ValueType can mess with sub class layouts.
+ * Causing bugs that appear completely unrelated as #30060
+ */
+ private static class Internal
+ {
+ public static int hash_code_of_ptr_seed = 0;
+ }
+
protected ValueType ()
{
}
[MethodImplAttribute (MethodImplOptions.InternalCall)]
- internal extern static bool InternalEquals (object o1, object o2, out object[] fields);
+ 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)
{
- object[] fields;
+ if (o1 == null && o2 == null)
+ return true;
+ if (o1 == null || o2 == null)
+ return false;
- if (o2 == null)
+ 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;
// True if this instance and o represent the same type
// and have the same value.
// </summary>
- public override bool Equals (object o) {
- return DefaultEquals (this, o);
+ public override bool Equals (object obj)
+ {
+ return DefaultEquals (this, obj);
}
[MethodImplAttribute (MethodImplOptions.InternalCall)]
return result;
}
+ internal static int GetHashCodeOfPtr (IntPtr ptr)
+ {
+ int hash_code = (int) ptr;
+ int seed = Internal.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 Internal.hash_code_of_ptr_seed, seed, 0);
+ seed = Internal.hash_code_of_ptr_seed;
+ }
+
+ return hash_code - seed;
+ }
+
// <summary>
// Stringified representation of this ValueType.
// Must be overriden for better results, by default