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.Collections.emptyList;
30 import static java.util.stream.Collectors.joining;
31 import static java.util.stream.Collectors.toList;
32 import static jdk.test.lib.process.ProcessTools.createJavaProcessBuilder;
33
34 import java.io.BufferedReader;
35 import java.io.File;
36 import java.io.FileNotFoundException;
37 import java.io.FileOutputStream;
38 import java.io.IOException;
39 import java.io.InputStreamReader;
40 import java.util.Collection;
41 import java.util.Optional;
42 import java.util.stream.Stream;
43
44 /*
45 * @test TestInheritFD
46 * @bug 8176717 8176809
47 * @summary a new process should not inherit open file descriptors
48 * @library /test/lib
49 * @modules java.base/jdk.internal.misc
50 * java.management
51 */
52
53 /**
54 * Test that HotSpot does not leak logging file descriptors.
55 *
56 * This test is performed in three steps. The first VM starts a second VM with
57 * gc logging enabled. The second VM starts a third VM and redirects the third
58 * VMs output to the first VM, it then exits and hopefully closes its log file.
59 *
60 * The third VM waits for the second to exit and close its log file. After that,
61 * the third VM tries to rename the log file of the second VM. If it succeeds in
62 * doing so it means that the third VM did not inherit the open log file
63 * (windows can not rename opened files easily)
64 *
65 * The third VM communicates the success to rename the file by printing "CLOSED
66 * FD". The first VM checks that the string was printed by the third VM.
67 *
68 * On unix like systems "lsof" or "pfiles" is used.
69 */
70
71 public class TestInheritFD {
72
73 public static final String LEAKS_FD = "VM RESULT => LEAKS FD";
74 public static final String RETAINS_FD = "VM RESULT => RETAINS FD";
75 public static final String EXIT = "VM RESULT => VM EXIT";
76 public static final String LOG_SUFFIX = ".strangelogsuffixthatcanbecheckedfor";
77
78 // first VM
79 public static void main(String[] args) throws Exception {
80 String logPath = createTempFile("logging", LOG_SUFFIX).getName();
81 File commFile = createTempFile("communication", ".txt");
82
83 ProcessBuilder pb = createJavaProcessBuilder(
84 "-Xlog:gc:\"" + logPath + "\"",
85 "-Dtest.jdk=" + getProperty("test.jdk"),
86 VMStartedWithLogging.class.getName(),
87 logPath);
88
89 pb.redirectOutput(commFile); // use temp file to communicate between processes
90 pb.start();
91
92 String out = "";
93 do {
94 out = new String(readAllBytes(commFile.toPath()));
95 Thread.sleep(100);
96 System.out.println("SLEEP 100 millis");
97 } while (!out.contains(EXIT));
98
99 System.out.println(out);
100 if (out.contains(RETAINS_FD)) {
101 System.out.println("Log file was not inherited by third VM");
102 } else {
103 throw new RuntimeException("could not match: " + RETAINS_FD);
104 }
105 }
106
107 static class VMStartedWithLogging {
108 // second VM
109 public static void main(String[] args) throws IOException, InterruptedException {
110 ProcessBuilder pb = createJavaProcessBuilder(
111 "-Dtest.jdk=" + getProperty("test.jdk"),
112 VMShouldNotInheritFileDescriptors.class.getName(),
113 args[0],
114 "" + ProcessHandle.current().pid());
115 pb.inheritIO(); // in future, redirect information from third VM to first VM
116 pb.start();
117
118 if (getProperty("os.name").toLowerCase().contains("win") == false) {
119 System.out.println("(Second VM) Open file descriptors:\n" + outputContainingFilenames().stream().collect(joining("\n")));
120 }
121 }
122 }
123
124 static class VMShouldNotInheritFileDescriptors {
125 // third VM
126 public static void main(String[] args) throws InterruptedException {
127 try {
128 File logFile = new File(args[0]);
129 long parentPid = parseLong(args[1]);
130 fakeLeakyJVM(false); // for debugging of test case
131
132 if (getProperty("os.name").toLowerCase().contains("win")) {
133 windows(logFile, parentPid);
134 } else {
135 Collection<String> output = outputContainingFilenames();
136 System.out.println("(Third VM) Open file descriptors:\n" + output.stream().collect(joining("\n")));
137 System.out.println(findOpenLogFile(output) ? LEAKS_FD : RETAINS_FD);
138 }
139 } catch (Exception e) {
140 System.out.println(e.toString());
141 } finally {
142 System.out.println(EXIT);
143 }
144 }
145 }
146
147 // for debugging of test case
148 @SuppressWarnings("resource")
149 static void fakeLeakyJVM(boolean fake) {
150 if (fake) {
151 try {
152 new FileOutputStream("fakeLeakyJVM" + LOG_SUFFIX, false);
153 } catch (FileNotFoundException e) {
154 }
155 }
156 }
157
158 static Stream<String> run(String... args){
159 try {
160 return new BufferedReader(new InputStreamReader(new ProcessBuilder(args).start().getInputStream())).lines();
161 } catch (IOException e) {
162 throw new RuntimeException(e);
163 }
164 }
165
166 static Collection<String> outputContainingFilenames() {
167 long pid = ProcessHandle.current().pid();
168 Optional<String[]> command = stream(new String[][]{
169 {"/usr/bin/lsof", "-p"},
170 {"/usr/sbin/lsof", "-p"},
171 {"/bin/lsof", "-p"},
172 {"/sbin/lsof", "-p"},
173 {"/usr/local/bin/lsof", "-p"},
174 {"/usr/bin/pfiles", "-F"}}) // Solaris
175 .filter(args -> new File(args[0]).exists())
176 .findFirst();
177
178 System.out.println("using command: " + command.map((c) -> c[0] + " " + c[1]).orElse("<not found>"));
179 // if command can not be found return list without log file (some machines does not have "lsof" in the expected place)
180 return command.map(c -> run(c[0], c[1], "" + pid).collect(toList())).orElse(emptyList());
181 }
182
183 static boolean findOpenLogFile(Collection<String> fileNames) {
184 return fileNames.stream()
185 .filter(fileName -> fileName.contains(LOG_SUFFIX))
186 .findAny()
187 .isPresent();
188 }
189
190 static void windows(File f, long parentPid) throws InterruptedException {
191 System.out.println("waiting for pid: " + parentPid);
192 ProcessHandle.of(parentPid).ifPresent(handle -> handle.onExit().join());
193 System.out.println("trying to rename file to the same name: " + f);
194 System.out.println(f.renameTo(f) ? RETAINS_FD : LEAKS_FD); // this parts communicates a closed file descriptor by printing "VM RESULT => RETAINS FD"
195 }