8242695: Enhanced buffer support

Brian Burkhalter · slowhog · commit fc5fca9ade89 · 2020-10-20T14:58:38.000-07:00
Reviewed-by: alanb, rhalade
diff --git a/src/java.base/windows/classes/sun/nio/fs/RegistryFileTypeDetector.java b/src/java.base/windows/classes/sun/nio/fs/RegistryFileTypeDetector.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2008, 2019, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2008, 2020, 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
@@ -55,10 +55,15 @@ public String implProbeContentType(Path file) throws IOException {
 
         // query HKEY_CLASSES_ROOT\<ext>
         String key = filename.substring(dot);
-        NativeBuffer keyBuffer = WindowsNativeDispatcher.asNativeBuffer(key);
-        NativeBuffer nameBuffer = WindowsNativeDispatcher.asNativeBuffer("Content Type");
+        NativeBuffer keyBuffer = null;
+        NativeBuffer nameBuffer = null;
         try {
+            keyBuffer = WindowsNativeDispatcher.asNativeBuffer(key);
+            nameBuffer = WindowsNativeDispatcher.asNativeBuffer("Content Type");
             return queryStringValue(keyBuffer.address(), nameBuffer.address());
+        } catch (WindowsException we) {
+            we.rethrowAsIOException(file.toString());
+            return null; // keep compiler happy
         } finally {
             nameBuffer.release();
             keyBuffer.release();
diff --git a/src/java.base/windows/classes/sun/nio/fs/WindowsNativeDispatcher.java b/src/java.base/windows/classes/sun/nio/fs/WindowsNativeDispatcher.java
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2008, 2019, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2008, 2020, 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
@@ -1123,7 +1123,12 @@ static native int GetOverlappedResult(long hFile, long lpOverlapped)
 
     private static final Unsafe unsafe = Unsafe.getUnsafe();
 
-    static NativeBuffer asNativeBuffer(String s) {
+    static NativeBuffer asNativeBuffer(String s) throws WindowsException {
+        if (s.length() > (Integer.MAX_VALUE - 2)/2) {
+            throw new WindowsException
+                ("String too long to convert to native buffer");
+        }
+
         int stringLengthInBytes = s.length() << 1;
         int sizeInBytes = stringLengthInBytes + 2;  // char terminator
 
