8021820: Number of opened files used in select() is limited to 1024 [macosx]
Reviewed-by: alanb, chegar, tbell, smarks
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/test/java/net/ServerSocket/SelectFdsLimit.java Fri Aug 16 18:41:35 2013 +0400
@@ -0,0 +1,104 @@
+/*
+ * 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 8021820
+ * @summary The total number of file descriptors is limited to
+ * 1024(FDSET_SIZE) on MacOSX (the size of fd array passed to select()
+ * call in java.net classes is limited to this value).
+ * @run main/othervm SelectFdsLimit
+ * @author aleksej.efimov@oracle.com
+ */
+
+import java.io.File;
+import java.io.FileInputStream;
+import java.io.FileNotFoundException;
+import java.io.IOException;
+import java.io.InputStream;
+import java.net.ServerSocket;
+import java.net.SocketTimeoutException;
+
+
+/*
+ * Test must be run in othervm mode to ensure that all files
+ * opened by openFiles() are closed propertly.
+*/
+public class SelectFdsLimit {
+ static final int FDTOOPEN = 1023;
+ static final String TESTFILE = "testfile";
+ static FileInputStream [] testFIS;
+
+ static void prepareTestEnv() throws IOException {
+ File fileToCreate = new File(TESTFILE);
+ if (!fileToCreate.exists())
+ if (!fileToCreate.createNewFile())
+ throw new RuntimeException("Can't create test file");
+ }
+
+ //If there will be some problem (i.e. ulimits on number of opened files will fail)
+ //then this method will fail with exception and test will be considered as
+ //failed. But allocated fds will be released because the test is executed by
+ //dedicated VM (@run main/othervm).
+ static void openFiles(int fn, File f) throws FileNotFoundException, IOException {
+ testFIS = new FileInputStream[FDTOOPEN];
+ for (;;) {
+ if (0 == fn)
+ break;
+ FileInputStream fis = new FileInputStream(f);
+ testFIS[--fn] = fis;
+ }
+ }
+
+ public static void main(String [] args) throws IOException, FileNotFoundException {
+
+ //The bug 8021820 is a Mac specific and because of that test will pass on all
+ //other platforms
+ if (!System.getProperty("os.name").contains("OS X")) {
+ return;
+ }
+
+ //Create test directory with test files
+ prepareTestEnv();
+
+ //Consume FD ids for this java process to overflow the 1024
+ openFiles(FDTOOPEN,new File(TESTFILE));
+
+ //Wait for incoming connection and make the select() used in java.net
+ //classes fail the limitation on FDSET_SIZE
+ ServerSocket socket = new ServerSocket(0);
+
+ //Set the minimal timeout, no one is
+ //going to connect to this server socket
+ socket.setSoTimeout(1);
+
+ // The accept() call will throw SocketException if the
+ // select() has failed due to limitation on fds size,
+ // indicating test failure. A SocketTimeoutException
+ // is expected, so it is caught and ignored, and the test
+ // passes.
+ try {
+ socket.accept();
+ } catch (SocketTimeoutException e) { }
+ }
+}