Fix incorrect bitmask in Pointer#createConstant(int) (#1472)

* Fix incorrect bitmask in Pointer#createConstant(int) * Update tests to match expectations

Author: dbwiddis

CHANGES.md

@@ -15,6 +15,7 @@ Bug Fixes
 ---------
 * [#1452](https://github.com/java-native-access/jna/issues/1452): Fix memory allocation/handling for error message generation in native library code (`dispatch.c`) - [@matthiasblaesing](https://github.com/matthiasblaesing).
 * [#1460](https://github.com/java-native-access/jna/issues/1460): Fix win32 variant date conversion in DST offest window and with millisecond values - [@eranl](https://github.com/eranl).
+* [#1472](https://github.com/java-native-access/jna/issues/1472): Fix incorrect bitmask in `c.s.j.Pointer#createConstant(int)` - [@dbwiddis](https://github.com/dbwiddis).
 
 Release 5.12.1
 ==============

contrib/platform/src/com/sun/jna/platform/win32/COM/util/ProxyObject.java

@@ -189,7 +189,7 @@ public boolean equals(Object arg) {
  @Override
  public int hashCode() {
  long id = this.getUnknownId();
- return (int) ((id >>> 32) & 0xFFFFFFFF) + (int) (id & 0xFFFFFFFF);
+ return (int) ((id >>> 32) + (id & 0xFFFFFFFFL));
  }
 
  @Override

src/com/sun/jna/Pointer.java

@@ -60,7 +60,7 @@ public static final Pointer createConstant(long peer) {
  systems.
  */
  public static final Pointer createConstant(int peer) {
- return new Opaque((long)peer & 0xFFFFFFFF);
+ return new Opaque(peer & 0xFFFFFFFFL);
  }
 
  /** Pointer value of the real native pointer. Use long to be 64-bit safe.
@@ -112,7 +112,7 @@ public boolean equals(Object o) {
 
  @Override
  public int hashCode() {
- return (int)((peer >>> 32) + (peer & 0xFFFFFFFF));
+ return (int) ((peer >>> 32) + (peer & 0xFFFFFFFFL));
  }
 
 

test/com/sun/jna/PointerTest.java

@@ -25,10 +25,11 @@
 
 package com.sun.jna;
 
+import java.lang.reflect.InvocationTargetException;
 import java.lang.reflect.Method;
 import java.lang.reflect.Modifier;
-import java.lang.reflect.InvocationTargetException;
 import java.util.Arrays;
+
 import junit.framework.TestCase;
 
 
@@ -174,10 +175,13 @@ public void testReadPointerArray() {
 
  public void testCreateConstantPointer() {
  Pointer p = Pointer.createConstant(0xFFFFFFFF);
- assertEquals("Wrong peer value", p.peer, 0xFFFFFFFF);
+ assertEquals("Wrong peer value", p.peer, 0xFFFFFFFFL);
 
- p = Pointer.createConstant(-1);
+ p = Pointer.createConstant(-1L);
  assertEquals("Wrong peer value", p.peer, -1);
+
+ p = Pointer.createConstant(0x80000000);
+ assertEquals("createConstant(int) should avoid setting any high bits", 0, Pointer.nativeValue(p) >>> 32);
  }
 
  public void testReadStringArrayNULLElement() {