8145981: (fs) LinuxWatchService can reports events against wrong directory
Summary: Fixes wakeup mechanism of LinuxWatchService and introduces a test
Reviewed-by: alanb
--- a/jdk/src/java.base/linux/classes/sun/nio/fs/LinuxWatchService.java Wed Dec 30 16:15:21 2015 +0000
+++ b/jdk/src/java.base/linux/classes/sun/nio/fs/LinuxWatchService.java Wed Dec 30 19:20:51 2015 +0100
@@ -322,19 +322,6 @@
bytesRead = 0;
}
- // process any pending requests
- if ((nReady > 1) || (nReady == 1 && bytesRead == 0)) {
- try {
- read(socketpair[0], address, BUFFER_SIZE);
- boolean shutdown = processRequests();
- if (shutdown)
- break;
- } catch (UnixException x) {
- if (x.errno() != UnixConstants.EAGAIN)
- throw x;
- }
- }
-
// iterate over buffer to decode events
int offset = 0;
while (offset < bytesRead) {
@@ -369,6 +356,19 @@
offset += (SIZEOF_INOTIFY_EVENT + len);
}
+
+ // process any pending requests
+ if ((nReady > 1) || (nReady == 1 && bytesRead == 0)) {
+ try {
+ read(socketpair[0], address, BUFFER_SIZE);
+ boolean shutdown = processRequests();
+ if (shutdown)
+ break;
+ } catch (UnixException x) {
+ if (x.errno() != UnixConstants.EAGAIN)
+ throw x;
+ }
+ }
}
} catch (UnixException x) {
x.printStackTrace();
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/test/java/nio/file/WatchService/UpdateInterference.java Wed Dec 30 19:20:51 2015 +0100
@@ -0,0 +1,107 @@
+/*
+ * Copyright (c) 2015, 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
+ * 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
+ * @bug 8145981
+ * @summary LinuxWatchService sometimes reports inotify events against wrong directory
+ * @run main UpdateInterference
+ */
+import java.io.IOException;
+import java.nio.file.*;
+import java.util.List;
+import java.util.concurrent.TimeUnit;
+import static java.nio.file.StandardWatchEventKinds.*;
+
+public class UpdateInterference {
+ public static void main(String[] args) throws IOException, InterruptedException {
+ final Path root = Files.createTempDirectory("test");
+ final Path foo = root.resolve("foo");
+ final Path bar = root.resolve("bar");
+ final Path baz = root.resolve("baz");
+
+ Files.createDirectory(foo);
+ Files.createDirectory(bar);
+ Files.createDirectory(baz);
+
+ final WatchService watcher = root.getFileSystem().newWatchService();
+ final WatchKey fooKey = foo.register(watcher, ENTRY_CREATE);
+ final WatchKey barKey = bar.register(watcher, ENTRY_CREATE);
+
+ new Thread() {
+ { setDaemon(true); }
+
+ @Override
+ public void run() {
+ while (true) {
+ try {
+ final Path temp = Files.createTempFile(foo, "temp", ".tmp");
+ Files.delete(temp);
+ Thread.sleep(10);
+ } catch (IOException | InterruptedException e) {
+ throw new RuntimeException(e);
+ }
+ }
+ }
+ }.start();
+
+ new Thread() {
+ { setDaemon(true); }
+
+ @Override
+ public void run() {
+ WatchKey bazKeys[] = new WatchKey[32];
+ while (true) {
+ try {
+ for( int i = 0; i < bazKeys.length; i++) {
+ bazKeys[i] = baz.register(watcher, ENTRY_CREATE);
+ }
+ for( int i = 0; i < bazKeys.length; i++) {
+ bazKeys[i].cancel();
+ }
+ Thread.sleep(1);
+ } catch (IOException | InterruptedException e) {
+ throw new RuntimeException(e);
+ }
+ }
+ }
+ }.start();
+
+ long time = System.currentTimeMillis();
+ while ((System.currentTimeMillis() - time) < 15000) {
+ final WatchKey key = watcher.poll(60, TimeUnit.SECONDS);
+ if (key == null) continue;
+
+ if (key != fooKey) {
+ List<WatchEvent<?>> pollEvents = key.pollEvents();
+ for (WatchEvent<?> watchEvent : pollEvents) {
+ System.out.println(watchEvent.count() + " " +
+ watchEvent.kind() + " " +
+ watchEvent.context());
+ }
+ throw new RuntimeException("Event received for unexpected key");
+ }
+ key.reset();
+ }
+ }
+}
+