8024833: (fc) FileChannel.map does not handle async close/interrupt correctly
authoralanb
Tue, 22 Oct 2013 12:04:19 +0100
changeset 21318 2dffe829fb18
parent 21317 176090ca2be7
child 21319 9bfb258734ce
child 21322 10b9b204a16a
child 22333 8af4eeeb9fa7
8024833: (fc) FileChannel.map does not handle async close/interrupt correctly Reviewed-by: alanb Contributed-by: chris.w.dennis@gmail.com
jdk/src/share/classes/sun/nio/ch/FileChannelImpl.java
jdk/test/java/nio/channels/FileChannel/InterruptMapDeadlock.java
--- a/jdk/src/share/classes/sun/nio/ch/FileChannelImpl.java	Tue Oct 22 11:43:04 2013 +0100
+++ b/jdk/src/share/classes/sun/nio/ch/FileChannelImpl.java	Tue Oct 22 12:04:19 2013 +0100
@@ -840,7 +840,15 @@
             ti = threads.add();
             if (!isOpen())
                 return null;
-            if (size() < position + size) { // Extend file size
+
+            long filesize;
+            do {
+                filesize = nd.size(fd);
+            } while ((filesize == IOStatus.INTERRUPTED) && isOpen());
+            if (!isOpen())
+                return null;
+
+            if (filesize < position + size) { // Extend file size
                 if (!writable) {
                     throw new IOException("Channel not open for writing " +
                         "- cannot extend file to required size");
@@ -849,6 +857,8 @@
                 do {
                     rv = nd.truncate(fd, position + size);
                 } while ((rv == IOStatus.INTERRUPTED) && isOpen());
+                if (!isOpen())
+                    return null;
             }
             if (size == 0) {
                 addr = 0;
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/test/java/nio/channels/FileChannel/InterruptMapDeadlock.java	Tue Oct 22 12:04:19 2013 +0100
@@ -0,0 +1,155 @@
+/*
+ * Copyright (c) 2013, 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 8024833
+ * @summary Tests interruption of threads mapping sections of a file channel in
+ *   an attempt to deadlock due to nesting of begin calls.
+ */
+import java.io.IOException;
+import java.nio.ByteBuffer;
+import java.nio.channels.*;
+import java.nio.channels.FileChannel.MapMode;
+import java.nio.file.*;
+import java.util.concurrent.Semaphore;
+import static java.nio.file.StandardOpenOption.*;
+
+public class InterruptMapDeadlock {
+
+    static class Mapper extends Thread {
+        final FileChannel fc;
+        final Semaphore gate;
+        volatile Exception exception;
+
+        Mapper(FileChannel fc, Semaphore gate) {
+            this.fc = fc;
+            this.gate = gate;
+        }
+
+        @Override
+        public void run() {
+            try {
+                gate.acquireUninterruptibly();
+                fc.map(MapMode.READ_ONLY, 0, 1);
+                throw new Exception("Map succeeded");
+            } catch (IOException x) {
+                System.out.println(x.getClass() + " (expected)");
+            } catch (Exception unexpected) {
+                this.exception = unexpected;
+            }
+        }
+
+        Exception exception() {
+            return exception;
+        }
+
+        static Mapper startMapper(FileChannel fc, Semaphore gate) {
+            Mapper r = new Mapper(fc, gate);
+            r.setDaemon(true);
+            r.start();
+            return r;
+        }
+    }
+
+    static class Interruptor extends Thread {
+
+        final Mapper[] mappers;
+        final Semaphore gate;
+
+        Interruptor(Mapper[] mappers, Semaphore gate) {
+            this.mappers = mappers;
+            this.gate = gate;
+        }
+
+        public void run() {
+            gate.release(mappers.length);
+            for (Mapper m : mappers) {
+                m.interrupt();
+            }
+        }
+    }
+    // the number of mapper threads to start
+    private static final int MAPPER_COUNT = 4;
+
+    public static void main(String[] args) throws Exception {
+        Path file = Paths.get("data.txt");
+        FileChannel.open(file, CREATE, TRUNCATE_EXISTING, WRITE).close();
+
+        Mapper[] mappers = new Mapper[MAPPER_COUNT];
+
+        for (int i=1; i<=20; i++) {
+            System.out.format("Iteration: %s%n", i);
+
+            FileChannel fc = FileChannel.open(file);
+            boolean failed = false;
+
+            Semaphore gate = new Semaphore(0);
+            // start mapper threads
+            for (int j=0; j<MAPPER_COUNT; j++) {
+                mappers[j] = Mapper.startMapper(fc, gate);
+            }
+
+            // interrupt and wait for the mappers to terminate
+            Interruptor interruptor = new Interruptor(mappers, gate);
+            interruptor.start();
+            try {
+                interruptor.join(10000);
+                if (interruptor.isAlive()) {
+                    System.err.println("Interruptor thread did not terminate:");
+                    Throwable t = new Exception("Stack trace");
+                    t.setStackTrace(interruptor.getStackTrace());
+                    t.printStackTrace();
+                    failed = true;
+                }
+            } catch (InterruptedException x) {
+                System.err.println("Main thread was interrupted");
+                failed = true;
+            }
+
+            for (Mapper m: mappers) {
+                try {
+                    m.join(10000);
+                    Exception e = m.exception();
+                    if (e != null) {
+                        System.err.println("Mapper thread failed with: " + e);
+                        failed = true;
+                    } else if (m.isAlive()) {
+                        System.err.println("Mapper thread did not terminate:");
+                        Throwable t = new Exception("Stack trace");
+                        t.setStackTrace(m.getStackTrace());
+                        t.printStackTrace();
+                        failed = true;
+                    }
+                } catch (InterruptedException x) {
+                    System.err.println("Main thread was interrupted");
+                    failed = true;
+                }
+            }
+
+            if (failed)
+                throw new RuntimeException("Test failed - see log for details");
+            else
+                fc.close();
+        }
+    }
+}