5041655: Force zero size of Long.MAX_VALUE - position; revert Windows change

Author: bplb

src/java.base/share/classes/java/nio/channels/FileLock.java

@@ -160,7 +160,7 @@ protected FileLock(FileChannel channel,
             throw new IllegalArgumentException("Negative position + size");
         this.channel = channel;
         this.position = position;
-        this.size = size;
+        this.size = size == 0 ? Long.MAX_VALUE - position : size;
         this.shared = shared;
     }
 
@@ -202,7 +202,7 @@ protected FileLock(AsynchronousFileChannel channel,
             throw new IllegalArgumentException("Negative position + size");
         this.channel = channel;
         this.position = position;
-        this.size = size;
+        this.size = size == 0 ? Long.MAX_VALUE - position : size;
         this.shared = shared;
     }
 
@@ -284,11 +284,17 @@ public final boolean isShared() {
      *          least one byte
      */
     public final boolean overlaps(long position, long size) {
-        System.out.printf("%d %d %d %d%n", this.position, this.size,
-            position, size);
         if (size < 0)
             return false;
 
+        try {
+            if (Math.addExact(this.position, this.size) <= position)
+                return false;               // This is below that
+        } catch (ArithmeticException ignored) {
+            // the sum of this.position and this.size overflows the range of
+            // long hence their mathematical sum is greater than position
+        }
+
         // if size == 0 then the specified lock range is unbounded and
         // cannot be below the range of this lock
         if (size > 0) {
@@ -301,18 +307,6 @@ public final boolean overlaps(long position, long size) {
             }
         }
 
-        // if this.size == 0 then the range of this lock is unbounded and
-        // cannot be below the specified lock range
-        if (this.size > 0) {
-            try {
-                if (Math.addExact(this.position, this.size) <= position)
-                    return false;               // This is below that
-            } catch (ArithmeticException ignored) {
-                // the sum of this.position and this.size overflows the range of
-                // long hence their mathematical sum is greater than position
-            }
-        }
-
         return true;
     }
 

src/java.base/windows/native/libnio/ch/FileDispatcherImpl.c

@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2000, 2022, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2000, 2018, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -389,15 +389,8 @@ Java_sun_nio_ch_FileDispatcherImpl_lock0(JNIEnv *env, jobject this, jobject fdo,
     HANDLE h = (HANDLE)(handleval(env, fdo));
     DWORD lowPos = (DWORD)pos;
     long highPos = (long)(pos >> 32);
-    DWORD lowNumBytes;
-    DWORD highNumBytes;
-    if (size == 0) {
-        lowNumBytes = MAXDWORD;
-        highNumBytes = MAXDWORD;
-    } else {
-        lowNumBytes = (DWORD)size;
-        highNumBytes = (DWORD)(size >> 32);
-    }
+    DWORD lowNumBytes = (DWORD)size;
+    DWORD highNumBytes = (DWORD)(size >> 32);
     BOOL result;
     DWORD flags = 0;
     OVERLAPPED o;
@@ -441,15 +434,8 @@ Java_sun_nio_ch_FileDispatcherImpl_release0(JNIEnv *env, jobject this,
     HANDLE h = (HANDLE)(handleval(env, fdo));
     DWORD lowPos = (DWORD)pos;
     long highPos = (long)(pos >> 32);
-    DWORD lowNumBytes;
-    DWORD highNumBytes;
-    if (size == 0) {
-        lowNumBytes = MAXDWORD;
-        highNumBytes = MAXDWORD;
-    } else {
-        lowNumBytes = (DWORD)size;
-        highNumBytes = (DWORD)(size >> 32);
-    }
+    DWORD lowNumBytes = (DWORD)size;
+    DWORD highNumBytes = (DWORD)(size >> 32);
     BOOL result = 0;
     OVERLAPPED o;
     o.hEvent = 0;