1 /* 2 * Copyright (c) 2016, 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. Oracle designates this 8 * particular file as subject to the "Classpath" exception as provided 9 * by Oracle in the LICENSE file that accompanied this code. 10 * 11 * This code is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 14 * version 2 for more details (a copy is included in the LICENSE file that 15 * accompanied this code). 16 * 17 * You should have received a copy of the GNU General Public License version 18 * 2 along with this work; if not, write to the Free Software Foundation, 19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 20 * 21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 22 * or visit www.oracle.com if you need additional information or have any 23 * questions. 24 */ 25 26 package jdk.jfr.internal.jfc; 27 28 import java.io.IOException; 29 import java.io.InputStream; 30 import java.io.Reader; 31 import java.nio.charset.StandardCharsets; 32 import java.nio.file.Files; 33 import java.nio.file.NoSuchFileException; 34 import java.nio.file.Path; 35 import java.nio.file.Paths; 36 import java.text.ParseException; 37 import java.util.ArrayList; 38 import java.util.Arrays; 39 import java.util.List; 40 41 import jdk.jfr.Configuration; 42 import jdk.jfr.internal.LogLevel; 43 import jdk.jfr.internal.LogTag; 44 import jdk.jfr.internal.Logger; 45 import jdk.jfr.internal.SecuritySupport; 46 import jdk.jfr.internal.SecuritySupport.SafePath; 47 48 /** 49 * {@link Configuration} factory for JFC files. * 50 */ 51 public final class JFC { 52 private static final int BUFFER_SIZE = 8192; 53 private static final int MAXIMUM_FILE_SIZE = 1024 * 1024; 54 private static final int MAX_BUFFER_SIZE = Integer.MAX_VALUE - 8; 55 private static volatile List<KnownConfiguration> knownConfigurations; 56 57 /** 58 * Reads a known configuration file (located into a string, but doesn't 59 * parse it until it's being used. 60 */ 61 private static final class KnownConfiguration { 62 private final String content; 63 private final String filename; 64 private final String name; 65 private Configuration configuration; 66 67 public KnownConfiguration(SafePath knownPath) throws IOException { 68 this.content = readContent(knownPath); 69 this.name = nameFromPath(knownPath.toPath()); 70 this.filename = nullSafeFileName(knownPath.toPath()); 71 } 72 73 public boolean isNamed(String name) { 74 return filename.equals(name) || this.name.equals(name); 75 } 76 77 public Configuration getConfigurationFile() throws IOException, ParseException { 78 if (configuration == null) { 79 configuration = JFCParser.createConfiguration(name, content); 80 } 81 return configuration; 82 } 83 84 public String getName() { 85 return name; 86 } 87 88 private static String readContent(SafePath knownPath) throws IOException { 89 if (SecuritySupport.getFileSize(knownPath) > MAXIMUM_FILE_SIZE) { 90 throw new IOException("Configuration with more than " 91 + MAXIMUM_FILE_SIZE + " characters can't be read."); 92 } 93 try (InputStream r = SecuritySupport.newFileInputStream(knownPath)) { 94 return JFC.readContent(r); 95 } 96 } 97 } 98 99 private JFC() { 100 // private utility class 101 } 102 103 /** 104 * Reads a configuration from a file. 105 * 106 * @param path the file containing the configuration, not {@code null} 107 * @return {@link Configuration}, not {@code null} 108 * @throws ParseException if the file can't be parsed 109 * @throws IOException if the file can't be read 110 * 111 * @throws SecurityException if a security manager exists and its 112 * <code>checkRead</code> method denies read access to the file. 113 * @see java.io.File#getPath() 114 * @see java.lang.SecurityManager#checkRead(java.lang.String) 115 */ 116 public static Configuration create(String name, Reader reader) throws IOException, ParseException { 117 return JFCParser.createConfiguration(name, reader); 118 } 119 120 private static String nullSafeFileName(Path file) throws IOException { 121 Path filename = file.getFileName(); 122 if (filename == null) { 123 throw new IOException("Path has no file name"); 124 } 125 return filename.toString(); 126 } 127 128 public static String nameFromPath(Path file) throws IOException { 129 String f = nullSafeFileName(file); 130 return f.substring(0, f.length() - JFCParser.FILE_EXTENSION.length()); 131 } 132 133 // Invoked by DCmdStart 134 public static Configuration createKnown(String name) throws IOException, ParseException { 135 // Known name, no need for permission 136 for (KnownConfiguration known : getKnownConfigurations()) { 137 if (known.isNamed(name)) { 138 return known.getConfigurationFile(); 139 } 140 } 141 // Check JFC directory 142 SafePath path = SecuritySupport.JFC_DIRECTORY; 143 if (path != null && SecuritySupport.exists(path)) { 144 for (String extension : Arrays.asList("", JFCParser.FILE_EXTENSION)) { 145 SafePath file = new SafePath(path.toPath().resolveSibling(name + extension)); 146 if (SecuritySupport.exists(file) && !SecuritySupport.isDirectory(file)) { 147 try (Reader r = SecuritySupport.newFileReader(file)) { 148 String jfcName = nameFromPath(file.toPath()); 149 return JFCParser.createConfiguration(jfcName, r); 150 } 151 } 152 } 153 } 154 155 // Assume path included in name 156 157 Path localPath = Paths.get(name); 158 String jfcName = nameFromPath(localPath); 159 try (Reader r = Files.newBufferedReader(localPath)) { 160 return JFCParser.createConfiguration(jfcName, r); 161 } 162 } 163 164 private static String readContent(InputStream source) throws IOException { 165 byte[] bytes = read(source, BUFFER_SIZE); 166 return new String(bytes, StandardCharsets.UTF_8); 167 } 168 169 // copied from java.io.file.Files to avoid dependency on JDK 9 code 170 private static byte[] read(InputStream source, int initialSize) throws IOException { 171 int capacity = initialSize; 172 byte[] buf = new byte[capacity]; 173 int nread = 0; 174 int n; 175 for (;;) { 176 // read to EOF which may read more or less than initialSize (eg: file 177 // is truncated while we are reading) 178 while ((n = source.read(buf, nread, capacity - nread)) > 0) 179 nread += n; 180 181 // if last call to source.read() returned -1, we are done 182 // otherwise, try to read one more byte; if that failed we're done too 183 if (n < 0 || (n = source.read()) < 0) 184 break; 185 186 // one more byte was read; need to allocate a larger buffer 187 if (capacity <= MAX_BUFFER_SIZE - capacity) { 188 capacity = Math.max(capacity << 1, BUFFER_SIZE); 189 } else { 190 if (capacity == MAX_BUFFER_SIZE) 191 throw new OutOfMemoryError("Required array size too large"); 192 capacity = MAX_BUFFER_SIZE; 193 } 194 buf = Arrays.copyOf(buf, capacity); 195 buf[nread++] = (byte)n; 196 } 197 return (capacity == nread) ? buf : Arrays.copyOf(buf, nread); 198 } 199 200 201 /** 202 * Returns list of predefined configurations available. 203 * 204 * @return list of configurations, not null 205 */ 206 public static List<Configuration> getConfigurations() { 207 List<Configuration> configs = new ArrayList<>(); 208 for (KnownConfiguration knownConfig : getKnownConfigurations()) { 209 try { 210 configs.add(knownConfig.getConfigurationFile()); 211 } catch (IOException e) { 212 Logger.log(LogTag.JFR, LogLevel.WARN, "Could not load configuration " + knownConfig.getName() + ". " + e.getMessage()); 213 } catch (ParseException e) { 214 Logger.log(LogTag.JFR, LogLevel.WARN, "Could not parse configuration " + knownConfig.getName() + ". " + e.getMessage()); 215 } 216 } 217 return configs; 218 } 219 220 private static List<KnownConfiguration> getKnownConfigurations() { 221 if (knownConfigurations == null) { 222 List<KnownConfiguration> configProxies = new ArrayList<>(); 223 for (SafePath p : SecuritySupport.getPredefinedJFCFiles()) { 224 try { 225 configProxies.add(new KnownConfiguration(p)); 226 } catch (IOException ioe) { 227 // ignore 228 } 229 } 230 knownConfigurations = configProxies; 231 } 232 return knownConfigurations; 233 } 234 235 public static Configuration getPredefined(String name) throws IOException, ParseException { 236 for (KnownConfiguration knownConfig : getKnownConfigurations()) { 237 if (knownConfig.getName().equals(name)) { 238 return knownConfig.getConfigurationFile(); 239 } 240 } 241 throw new NoSuchFileException("Could not locate configuration with name " + name); 242 } 243 }