JBR-3680 Cherry-pick Google's NIO patches to get faster file listing

Fix regression introduced by Google's NIO patches:
- do not attempt to get the next entry after the directory stream has
been closed already,
- fix FaultyFileSystem that is used in StreamTest.java to throw
the right exception even when getFileAttributeView() is used instead of
readAttributes(),
- removed unnecessary type cast that caused a compilation warning.

Added a test for walking a directory with a non-latin name.

(cherry picked from commit 152a4e886d)

src/java.base/windows/classes/sun/nio/fs/WindowsDirectoryStream.java

@@ -157,6 +157,11 @@ class WindowsDirectoryStream
                 // synchronize on closeLock to prevent close while reading
                 synchronized (closeLock) {
                     // Fetch next set of entries if we don't have anything available in buffer
+                    if (!isOpen) {
+                        atEof = true;
+                        return null;
+                    }
+
                     if (nextOffset < 0) {
                         try {
                             atEof = !NextNtQueryDirectoryInformation(queryDirectoryInformation, queryDirectoryInformationBuffer);

src/java.base/windows/classes/sun/nio/fs/WindowsFileKey.java

@@ -40,7 +40,7 @@ class WindowsFileKey {
 
     @Override
     public int hashCode() {
-        return (int)(volSerialNumber ^ (volSerialNumber >>> 16)) +
+        return (volSerialNumber ^ (volSerialNumber >>> 16)) +
                (int)(fileId ^ (fileId >>> 32));
     }
 

test/jdk/java/nio/file/Files/FaultyFileSystem.java

@@ -42,6 +42,8 @@ import java.nio.file.WatchService;
 import java.nio.file.attribute.BasicFileAttributes;
 import java.nio.file.attribute.FileAttribute;
 import java.nio.file.attribute.FileAttributeView;
+import java.nio.file.attribute.FileTime;
+import java.nio.file.attribute.BasicFileAttributeView;
 import java.nio.file.attribute.UserPrincipalLookupService;
 import java.nio.file.spi.FileSystemProvider;
 import java.util.Iterator;
@@ -323,12 +325,44 @@ class FaultyFileSystem extends FileSystem {
             return Files.readAttributes(unwrap(file), attributes, options);
         }
 
+        private class FaultyBasicFileAttributeView implements BasicFileAttributeView {
+            private final Path file;
+            private final LinkOption[] options;
+
+            public FaultyBasicFileAttributeView(final Path file, final LinkOption... options) {
+                this.file = file;
+                this.options = options;
+            }
+
+            @Override
+            public String name() {
+                return "faulty";
+            }
+
+            @Override
+            public BasicFileAttributes readAttributes() throws IOException {
+                triggerEx(file, "readAttributes");
+                return Files.readAttributes(file, BasicFileAttributes.class, options);
+            }
+
+            @Override
+            public void setTimes(FileTime lastModifiedTime,
+                          FileTime lastAccessTime,
+                          FileTime createTime) throws IOException {
+                triggerEx(file, "setTimes");
+            }
+        }
+
         @Override
         public <V extends FileAttributeView> V getFileAttributeView(Path file,
                                                                     Class<V> type,
                                                                     LinkOption... options)
         {
-            return Files.getFileAttributeView(unwrap(file), type, options);
+            if (type != BasicFileAttributeView.class) {
+                return null;
+            }
+
+            return (V)new FaultyBasicFileAttributeView(unwrap(file), options);
         }
 
         @Override

test/jdk/java/nio/file/Files/walkFileTree/NonLatin.java

@@ -0,0 +1,80 @@
+/*
+ * Copyright (c) 2021, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2021, JetBrains s.r.o.. 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
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+/*
+ * @test
+ * @summary Tests that walkFileTree can find files in a directory with
+ *          non-latin characters in the name (including ones from
+ *          the supplementary plane)
+ * @library /test/lib
+ */
+
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+import java.nio.file.FileVisitOption;
+import java.nio.file.SimpleFileVisitor;
+import java.nio.file.FileVisitResult;
+import java.nio.file.attribute.BasicFileAttributes;
+import java.util.Vector;
+import java.util.HashSet;
+
+import jdk.test.lib.Asserts;
+
+public class NonLatin {
+    // Use non-Latin characters from basic (\u1889) and supplementary (\uD844\uDDD9) Unicode planes
+    private static final String NON_LATIN_PATH_NAME = "ka-\u1889-supp-\uD844\uDDD9";
+
+    public static void main(String args[]) throws Exception {
+        final Path currentDirPath = Paths.get(".").toAbsolutePath();
+        Path nonLatinPath = null;
+
+        try {
+            nonLatinPath = currentDirPath.resolve(NON_LATIN_PATH_NAME);
+            Files.createDirectory(nonLatinPath);
+            final Path underNonLatinPath = nonLatinPath.resolve("dir");
+            Files.createDirectory(underNonLatinPath);
+        } catch (java.nio.file.InvalidPathException e) {
+            System.out.println("Cannot create the directory with the right name. Test is considered passed");
+            return;
+        }
+
+        final Vector<String> visitedDirs = new Vector<String>();
+
+        Files.walkFileTree(nonLatinPath, new HashSet<FileVisitOption>(), Integer.MAX_VALUE, new SimpleFileVisitor<Path>() {
+            @Override
+            public FileVisitResult preVisitDirectory(Path dir, BasicFileAttributes attrs) {
+                visitedDirs.add(dir.toString());
+                return FileVisitResult.CONTINUE;
+            }
+        });
+
+        boolean found = false;
+        for (final String dirName : visitedDirs) {
+            System.out.println("Found: " + dirName);
+            found |= dirName.contains(NON_LATIN_PATH_NAME);
+        }
+        Asserts.assertTrue(found);
+    }
+}