PrintStreamOptionKey.java revision 12995:5e441a7ec5e3 
1/*
2 * Copyright (c) 2014, 2015, 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 */
23package org.graalvm.compiler.hotspot;
24
25import java.io.FileNotFoundException;
26import java.io.FileOutputStream;
27import java.io.IOException;
28import java.io.OutputStream;
29import java.io.PrintStream;
30import java.lang.management.ManagementFactory;
31
32import org.graalvm.compiler.options.OptionKey;
33import org.graalvm.compiler.options.OptionValues;
34
35import jdk.vm.ci.hotspot.HotSpotJVMCIRuntime;
36import jdk.vm.ci.hotspot.HotSpotJVMCIRuntimeProvider;
37
38/**
39 * An option that encapsulates and configures a print stream.
40 */
41public class PrintStreamOptionKey extends OptionKey<String> {
42
43    public PrintStreamOptionKey() {
44        super(null);
45    }
46
47    /**
48     * Replace any instance of %p with an identifying name. Try to get it from the RuntimeMXBean
49     * name.
50     *
51     * @return the name of the file to log to
52     */
53    private String getFilename(OptionValues options) {
54        String name = getValue(options);
55        if (name.contains("%p")) {
56            String runtimeName = ManagementFactory.getRuntimeMXBean().getName();
57            try {
58                int index = runtimeName.indexOf('@');
59                if (index != -1) {
60                    long pid = Long.parseLong(runtimeName.substring(0, index));
61                    runtimeName = Long.toString(pid);
62                }
63                name = name.replaceAll("%p", runtimeName);
64            } catch (NumberFormatException e) {
65
66            }
67        }
68        return name;
69    }
70
71    /**
72     * An output stream that redirects to {@link HotSpotJVMCIRuntimeProvider#getLogStream()}. The
73     * {@link HotSpotJVMCIRuntimeProvider#getLogStream()} value is only accessed the first time an
74     * IO operation is performed on the stream. This is required to break a deadlock in early JVMCI
75     * initialization.
76     */
77    static class DelayedOutputStream extends OutputStream {
78        private volatile OutputStream lazy;
79
80        private OutputStream lazy() {
81            if (lazy == null) {
82                synchronized (this) {
83                    if (lazy == null) {
84                        lazy = HotSpotJVMCIRuntime.runtime().getLogStream();
85                    }
86                }
87            }
88            return lazy;
89        }
90
91        @Override
92        public void write(byte[] b, int off, int len) throws IOException {
93            lazy().write(b, off, len);
94        }
95
96        @Override
97        public void write(int b) throws IOException {
98            lazy().write(b);
99        }
100
101        @Override
102        public void flush() throws IOException {
103            lazy().flush();
104        }
105
106        @Override
107        public void close() throws IOException {
108            lazy().close();
109        }
110    }
111
112    /**
113     * Gets the print stream configured by this option. If no file is configured, the print stream
114     * will output to HotSpot's {@link HotSpotJVMCIRuntimeProvider#getLogStream() log} stream.
115     */
116    public PrintStream getStream(OptionValues options) {
117        if (getValue(options) != null) {
118            try {
119                final boolean enableAutoflush = true;
120                PrintStream ps = new PrintStream(new FileOutputStream(getFilename(options)), enableAutoflush);
121                /*
122                 * Add the JVM and Java arguments to the log file to help identity it.
123                 */
124                String inputArguments = String.join(" ", ManagementFactory.getRuntimeMXBean().getInputArguments());
125                ps.println("VM Arguments: " + inputArguments);
126                String cmd = System.getProperty("sun.java.command");
127                if (cmd != null) {
128                    ps.println("sun.java.command=" + cmd);
129                }
130                return ps;
131            } catch (FileNotFoundException e) {
132                throw new RuntimeException("couldn't open file: " + getValue(options), e);
133            }
134        } else {
135            return new PrintStream(new DelayedOutputStream());
136        }
137    }
138}
139