1 /*
2 * Copyright (c) 2018, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 */
23
24 import static java.io.File.createTempFile;
25 import static java.lang.Long.parseLong;
26 import static java.lang.System.getProperty;
27 import static java.nio.file.Files.readAllBytes;
28 import static java.util.Arrays.stream;
29 import static java.util.stream.Collectors.joining;
30 import static java.util.stream.Collectors.toList;
31 import static jdk.test.lib.process.ProcessTools.createJavaProcessBuilder;
32
33 import java.io.BufferedReader;
34 import java.io.File;
35 import java.io.FileNotFoundException;
36 import java.io.FileOutputStream;
37 import java.io.IOException;
38 import java.io.InputStreamReader;
39 import java.util.Collection;
40 import java.util.Optional;
41 import java.util.stream.Stream;
42
43 /*
44 * @test TestInheritFD
45 * @bug 8176717 8176809
46 * @summary a new process should not inherit open file descriptors
47 * @library /test/lib
48 * @modules java.base/jdk.internal.misc
49 * java.management
50 */
51
52 /**
53 * Test that HotSpot does not leak logging file descriptors.
54 *
55 * This test is performed in three steps. The first VM starts a second VM with
56 * gc logging enabled. The second VM starts a third VM and redirects the third
57 * VMs output to the first VM, it then exits and hopefully closes its log file.
58 *
59 * The third VM waits for the second to exit and close its log file. After that,
60 * the third VM tries to rename the log file of the second VM. If it succeeds in
61 * doing so it means that the third VM did not inherit the open log file
62 * (windows can not rename opened files easily)
63 *
64 * The third VM communicates the success to rename the file by printing "CLOSED
65 * FD". The first VM checks that the string was printed by the third VM.
66 *
67 * On unix like systems "lsof" or "pfiles" is used.
68 */
69
70 public class TestInheritFD {
71
72 public static final String LEAKS_FD = "VM RESULT => LEAKS FD";
73 public static final String RETAINS_FD = "VM RESULT => RETAINS FD";
74 public static final String EXIT = "VM RESULT => VM EXIT";
75 public static final String LOG_SUFFIX = ".strangelogsuffixthatcanbecheckedfor";
76
77 // first VM
78 public static void main(String[] args) throws Exception {
79 String logPath = createTempFile("logging", LOG_SUFFIX).getName();
80 File commFile = createTempFile("communication", ".txt");
81
82 if (isWindows() == false && lsofCommand().isPresent() == false) {
83 System.out.println("Could not find lsof like command");
84 System.out.println("Exit test case as successful though it could not verify anything");
85 return;
86 }
87
88 ProcessBuilder pb = createJavaProcessBuilder(
89 "-Xlog:gc:\"" + logPath + "\"",
90 "-Dtest.jdk=" + getProperty("test.jdk"),
91 VMStartedWithLogging.class.getName(),
92 logPath);
93
94 pb.redirectOutput(commFile); // use temp file to communicate between processes
95 pb.start();
96
97 String out = "";
98 do {
99 out = new String(readAllBytes(commFile.toPath()));
100 Thread.sleep(100);
101 System.out.println("SLEEP 100 millis");
102 } while (!out.contains(EXIT));
103
104 System.out.println(out);
105 if (out.contains(RETAINS_FD)) {
106 System.out.println("Log file was not inherited by third VM");
107 } else {
108 throw new RuntimeException("could not match: " + RETAINS_FD);
109 }
110 }
111
112 static class VMStartedWithLogging {
113 // second VM
114 public static void main(String[] args) throws IOException, InterruptedException {
115 ProcessBuilder pb = createJavaProcessBuilder(
116 "-Dtest.jdk=" + getProperty("test.jdk"),
117 VMShouldNotInheritFileDescriptors.class.getName(),
118 args[0],
119 "" + ProcessHandle.current().pid());
120 pb.inheritIO(); // in future, redirect information from third VM to first VM
121 pb.start();
122
123 if (!isWindows()) {
124 System.out.println("(Second VM) Open file descriptors:\n" + outputContainingFilenames().stream().collect(joining("\n")));
125 }
126 }
127 }
128
129 static class VMShouldNotInheritFileDescriptors {
130 // third VM
131 public static void main(String[] args) throws InterruptedException {
132 try {
133 File logFile = new File(args[0]);
134 long parentPid = parseLong(args[1]);
135 fakeLeakyJVM(false); // for debugging of test case
136
137 if (isWindows()) {
138 windows(logFile, parentPid);
139 } else {
140 Collection<String> output = outputContainingFilenames();
141 System.out.println("(Third VM) Open file descriptors:\n" + output.stream().collect(joining("\n")));
142 System.out.println(findOpenLogFile(output) ? LEAKS_FD : RETAINS_FD);
143 }
144 } catch (Exception e) {
145 System.out.println(e.toString());
146 } finally {
147 System.out.println(EXIT);
148 }
149 }
150 }
151
152 // for debugging of test case
153 @SuppressWarnings("resource")
154 static void fakeLeakyJVM(boolean fake) {
155 if (fake) {
156 try {
157 new FileOutputStream("fakeLeakyJVM" + LOG_SUFFIX, false);
158 } catch (FileNotFoundException e) {
159 }
160 }
161 }
162
163 static Stream<String> run(String... args){
164 try {
165 return new BufferedReader(new InputStreamReader(new ProcessBuilder(args).start().getInputStream())).lines();
166 } catch (IOException e) {
167 throw new RuntimeException(e);
168 }
169 }
170
171 static boolean isWindows() {
172 return getProperty("os.name").toLowerCase().contains("win");
173 }
174
175 static Optional<String[]> lsofCommand() {
176 return stream(new String[][]{
177 {"/usr/bin/lsof", "-p"},
178 {"/usr/sbin/lsof", "-p"},
179 {"/bin/lsof", "-p"},
180 {"/sbin/lsof", "-p"},
181 {"/usr/local/bin/lsof", "-p"},
182 {"/usr/bin/pfiles", "-F"}}) // Solaris
183 .filter(args -> new File(args[0]).exists())
184 .findFirst();
185 }
186
187 static Collection<String> outputContainingFilenames() {
188 long pid = ProcessHandle.current().pid();
189
190 String[] command = lsofCommand().orElseThrow(() -> new RuntimeException("lsof like command not found"));
191 System.out.println("using command: " + command[0] + " " + command[1]);
192 return run(command[0], command[1], "" + pid).collect(toList());
193 }
194
195 static boolean findOpenLogFile(Collection<String> fileNames) {
196 return fileNames.stream()
197 .filter(fileName -> fileName.contains(LOG_SUFFIX))
198 .findAny()
199 .isPresent();
200 }
201
202 static void windows(File f, long parentPid) throws InterruptedException {
203 System.out.println("waiting for pid: " + parentPid);
204 ProcessHandle.of(parentPid).ifPresent(handle -> handle.onExit().join());
205 System.out.println("trying to rename file to the same name: " + f);
206 System.out.println(f.renameTo(f) ? RETAINS_FD : LEAKS_FD); // this parts communicates a closed file descriptor by printing "VM RESULT => RETAINS FD"
207 }