1 /*

     2  * Copyright (c) 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.  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 package jdk.internal.jrtfs;

    26 

    27 import java.io.IOException;

    28 import java.nio.file.DirectoryStream;

    29 import java.nio.file.FileSystem;

    30 import java.nio.file.FileSystemException;

    31 import java.nio.file.FileSystems;

    32 import java.nio.file.Files;

    33 import java.nio.file.LinkOption;

    34 import java.nio.file.NoSuchFileException;

    35 import java.nio.file.NotDirectoryException;

    36 import java.nio.file.Path;

    37 import java.nio.file.attribute.BasicFileAttributes;

    38 import java.util.ArrayList;

    39 import java.util.Collections;

    40 import java.util.HashMap;

    41 import java.util.Iterator;

    42 import java.util.List;

    43 import java.util.Map;

    44 import java.util.function.Function;

    45 import static java.util.stream.Collectors.toList;

    46 import static jdk.internal.jrtfs.AbstractJrtFileSystem.getString;

    47 

    48 /**

    49  * A jrt file system built on $JAVA_HOME/modules directory ('exploded modules

    50  * build')

    51  *

    52  * @implNote This class needs to maintain JDK 8 source compatibility.

    53  *

    54  * It is used internally in the JDK to implement jimage/jrtfs access,

    55  * but also compiled and delivered as part of the jrtfs.jar to support access

    56  * to the jimage file provided by the shipped JDK by tools running on JDK 8.

    57  */

    58 class JrtExplodedFileSystem extends AbstractJrtFileSystem {

    59 

    60     private static final String MODULES = "/modules/";

    61     private static final String PACKAGES = "/packages/";

    62     private static final int PACKAGES_LEN = PACKAGES.length();

    63 

    64     // root path

    65     private final JrtExplodedPath rootPath;

    66     private volatile boolean isOpen;

    67     private final FileSystem defaultFS;

    68     private final String separator;

    69     private final Map<String, Node> nodes = Collections.synchronizedMap(new HashMap<>());

    70     private final BasicFileAttributes modulesDirAttrs;

    71 

    72     JrtExplodedFileSystem(JrtFileSystemProvider provider,

    73             Map<String, ?> env)

    74             throws IOException {

    75 

    76         super(provider, env);

    77         checkExists(SystemImages.explodedModulesDir());

    78         byte[] root = new byte[]{'/'};

    79         rootPath = new JrtExplodedPath(this, root);

    80         isOpen = true;

    81         defaultFS = FileSystems.getDefault();

    82         String str = defaultFS.getSeparator();

    83         separator = str.equals(getSeparator()) ? null : str;

    84         modulesDirAttrs = Files.readAttributes(SystemImages.explodedModulesDir(), BasicFileAttributes.class);

    85         initNodes();

    86     }

    87 

    88     @Override

    89     public void close() throws IOException {

    90         cleanup();

    91     }

    92 

    93     @Override

    94     public boolean isOpen() {

    95         return isOpen;

    96     }

    97 

    98     @Override

    99     protected void finalize() throws Throwable {

   100         cleanup();

   101         super.finalize();

   102     }

   103 

   104     private synchronized void cleanup() {

   105         isOpen = false;

   106         nodes.clear();

   107     }

   108 

   109     @Override

   110     JrtExplodedPath getRootPath() {

   111         return rootPath;

   112     }

   113 

   114     // Base class for Nodes of this file system

   115     abstract class Node {

   116 

   117         private final String name;

   118 

   119         Node(String name) {

   120             this.name = name;

   121         }

   122 

   123         final String getName() {

   124             return name;

   125         }

   126 

   127         final String getExtension() {

   128             if (isFile()) {

   129                 final int index = name.lastIndexOf(".");

   130                 if (index != -1) {

   131                     return name.substring(index + 1);

   132                 }

   133             }

   134 

   135             return null;

   136         }

   137 

   138         BasicFileAttributes getBasicAttrs() throws IOException {

   139             return modulesDirAttrs;

   140         }

   141 

   142         boolean isLink() {

   143             return false;

   144         }

   145 

   146         boolean isDirectory() {

   147             return false;

   148         }

   149 

   150         boolean isFile() {

   151             return false;

   152         }

   153 

   154         byte[] getContent() throws IOException {

   155             if (!isFile()) {

   156                 throw new FileSystemException(name + " is not file");

   157             }

   158 

   159             throw new AssertionError("ShouldNotReachHere");

   160         }

   161 

   162         List<Node> getChildren() throws IOException {

   163             if (!isDirectory()) {

   164                 throw new NotDirectoryException(name);

   165             }

   166 

   167             throw new AssertionError("ShouldNotReachHere");

   168         }

   169 

   170         final Node resolveLink() {

   171             return resolveLink(false);

   172         }

   173 

   174         Node resolveLink(boolean recursive) {

   175             return this;

   176         }

   177     }

   178 

   179     // A Node that is backed by actual default file system Path

   180     private final class PathNode extends Node {

   181 

   182         // Path in underlying default file system

   183         private final Path path;

   184         private final boolean file;

   185         // lazily initialized, don't read attributes unless required!

   186         private BasicFileAttributes attrs;

   187 

   188         PathNode(String name, Path path) {

   189             super(name);

   190             this.path = path;

   191             this.file = Files.isRegularFile(path);

   192         }

   193 

   194         @Override

   195         synchronized BasicFileAttributes getBasicAttrs() throws IOException {

   196             if (attrs == null) {

   197                 attrs = Files.readAttributes(path, BasicFileAttributes.class);

   198             }

   199             return attrs;

   200         }

   201 

   202         @Override

   203         boolean isDirectory() {

   204             return !file;

   205         }

   206 

   207         @Override

   208         boolean isFile() {

   209             return file;

   210         }

   211 

   212         @Override

   213         byte[] getContent() throws IOException {

   214             if (!isFile()) {

   215                 throw new FileSystemException(getName() + " is not file");

   216             }

   217 

   218             return Files.readAllBytes(path);

   219         }

   220 

   221         @Override

   222         List<Node> getChildren() throws IOException {

   223             if (!isDirectory()) {

   224                 throw new NotDirectoryException(getName());

   225             }

   226 

   227             List<Node> children = new ArrayList<>();

   228             try (DirectoryStream<Path> stream = Files.newDirectoryStream(path)) {

   229                 for (Path cp : stream) {

   230                     cp = SystemImages.explodedModulesDir().relativize(cp);

   231                     String cpName = MODULES + nativeSlashToFrontSlash(cp.toString());

   232                     try {

   233                         children.add(findNode(cpName));

   234                     } catch (NoSuchFileException nsfe) {

   235                         // findNode may choose to hide certain files!

   236                     }

   237                 }

   238             }

   239 

   240             return children;

   241         }

   242     }

   243 

   244     // A Node that links to another Node

   245     private final class LinkNode extends Node {

   246 

   247         // underlying linked Node

   248         private final Node link;

   249 

   250         LinkNode(String name, Node link) {

   251             super(name);

   252             this.link = link;

   253         }

   254 

   255         @Override

   256         BasicFileAttributes getBasicAttrs() throws IOException {

   257             return link.getBasicAttrs();

   258         }

   259 

   260         @Override

   261         public boolean isLink() {

   262             return true;

   263         }

   264 

   265         @Override

   266         Node resolveLink(boolean recursive) {

   267             return recursive && (link instanceof LinkNode) ? ((LinkNode) link).resolveLink(true) : link;

   268         }

   269     }

   270 

   271     // A directory Node with it's children Nodes

   272     private final class DirNode extends Node {

   273 

   274         // children Nodes of this Node.

   275         private final List<Node> children;

   276 

   277         DirNode(String name, List<Node> children) {

   278             super(name);

   279             this.children = children;

   280         }

   281 

   282         @Override

   283         boolean isDirectory() {

   284             return true;

   285         }

   286 

   287         @Override

   288         List<Node> getChildren() throws IOException {

   289             return children;

   290         }

   291     }

   292 

   293     private JrtExplodedPath toJrtExplodedPath(String path) {

   294         return toJrtExplodedPath(getBytes(path));

   295     }

   296 

   297     private JrtExplodedPath toJrtExplodedPath(byte[] path) {

   298         return new JrtExplodedPath(this, path);

   299     }

   300 

   301     @Override

   302     boolean isSameFile(AbstractJrtPath jrtPath1, AbstractJrtPath jrtPath2) throws IOException {

   303         Node n1 = checkNode(jrtPath1);

   304         Node n2 = checkNode(jrtPath2);

   305         return n1 == n2;

   306     }

   307 

   308     @Override

   309     boolean isLink(AbstractJrtPath jrtPath) throws IOException {

   310         return checkNode(jrtPath).isLink();

   311     }

   312 

   313     @Override

   314     AbstractJrtPath resolveLink(AbstractJrtPath jrtPath) throws IOException {

   315         String name = checkNode(jrtPath).resolveLink().getName();

   316         return toJrtExplodedPath(name);

   317     }

   318 

   319     @Override

   320     AbstractJrtFileAttributes getFileAttributes(AbstractJrtPath jrtPath, LinkOption... options) throws IOException {

   321         Node node = checkNode(jrtPath);

   322         if (node.isLink() && followLinks(options)) {

   323             node = node.resolveLink(true);

   324         }

   325         return new JrtExplodedFileAttributes(node);

   326     }

   327 

   328     @Override

   329     boolean exists(AbstractJrtPath jrtPath) throws IOException {

   330         try {

   331             checkNode(jrtPath);

   332             return true;

   333         } catch (NoSuchFileException nsfe) {

   334             return false;

   335         }

   336     }

   337 

   338     @Override

   339     boolean isDirectory(AbstractJrtPath jrtPath, boolean resolveLinks) throws IOException {

   340         Node node = checkNode(jrtPath);

   341         return resolveLinks && node.isLink()

   342                 ? node.resolveLink(true).isDirectory()

   343                 : node.isDirectory();

   344     }

   345 

   346     @Override

   347     Iterator<Path> iteratorOf(AbstractJrtPath dir) throws IOException {

   348         Node node = checkNode(dir).resolveLink(true);

   349         if (!node.isDirectory()) {

   350             throw new NotDirectoryException(getString(dir.getName()));

   351         }

   352 

   353         Function<Node, Path> nodeToPath =

   354             child -> dir.resolve(

   355                 toJrtExplodedPath(child.getName()).

   356                 getFileName());

   357 

   358         return node.getChildren().stream().

   359                    map(nodeToPath).collect(toList()).

   360                    iterator();

   361     }

   362 

   363     @Override

   364     byte[] getFileContent(AbstractJrtPath jrtPath) throws IOException {

   365         return checkNode(jrtPath).getContent();

   366     }

   367 

   368     private Node checkNode(AbstractJrtPath jrtPath) throws IOException {

   369         return checkNode(jrtPath.getResolvedPath());

   370     }

   371 

   372     private Node checkNode(byte[] path) throws IOException {

   373         ensureOpen();

   374         return findNode(path);

   375     }

   376 

   377     synchronized Node findNode(byte[] path) throws IOException {

   378         return findNode(getString(path));

   379     }

   380 

   381     // find Node for the given Path

   382     synchronized Node findNode(String str) throws IOException {

   383         Node node = findModulesNode(str);

   384         if (node != null) {

   385             return node;

   386         }

   387 

   388         // lazily created for paths like /packages/<package>/<module>/xyz

   389         // For example /packages/java.lang/java.base/java/lang/

   390         if (str.startsWith(PACKAGES)) {

   391             // pkgEndIdx marks end of <package> part

   392             int pkgEndIdx = str.indexOf('/', PACKAGES_LEN);

   393             if (pkgEndIdx != -1) {

   394                 // modEndIdx marks end of <module> part

   395                 int modEndIdx = str.indexOf('/', pkgEndIdx + 1);

   396                 if (modEndIdx != -1) {

   397                     // make sure we have such module link!

   398                     // ie., /packages/<package>/<module> is valid

   399                     Node linkNode = nodes.get(str.substring(0, modEndIdx));

   400                     if (linkNode == null || !linkNode.isLink()) {

   401                         throw new NoSuchFileException(str);

   402                     }

   403 

   404                     // map to "/modules/zyz" path and return that node

   405                     // For example, "/modules/java.base/java/lang" for

   406                     // "/packages/java.lang/java.base/java/lang".

   407                     String mod = MODULES + str.substring(pkgEndIdx + 1);

   408                     return findNode(mod);

   409                 }

   410             }

   411         }

   412 

   413         throw new NoSuchFileException(str);

   414     }

   415 

   416     // find a Node for a path that starts like "/modules/..."

   417     synchronized Node findModulesNode(String str) throws IOException {

   418         Node node = nodes.get(str);

   419         if (node != null) {

   420             return node;

   421         }

   422 

   423         // lazily created "/modules/xyz/abc/" Node

   424         // This is mapped to default file system path "<JDK_MODULES_DIR>/xyz/abc"

   425         Path p = underlyingPath(str);

   426         if (p != null) {

   427             if (Files.isRegularFile(p)) {

   428                 Path file = p.getFileName();

   429                 if (file.toString().startsWith("_the.")) {

   430                     return null;

   431                 }

   432             }

   433             node = new PathNode(str, p);

   434             nodes.put(str, node);

   435             return node;

   436         }

   437 

   438         return null;

   439     }

   440 

   441     Path underlyingPath(String str) {

   442         if (str.startsWith(MODULES)) {

   443             str = frontSlashToNativeSlash(str.substring("/modules".length()));

   444             return defaultFS.getPath(SystemImages.explodedModulesDir().toString(), str);

   445         }

   446         return null;

   447     }

   448 

   449     // convert "/" to platform path separator

   450     private String frontSlashToNativeSlash(String str) {

   451         return separator == null ? str : str.replace("/", separator);

   452     }

   453 

   454     // convert platform path separator to "/"

   455     private String nativeSlashToFrontSlash(String str) {

   456         return separator == null ? str : str.replace(separator, "/");

   457     }

   458 

   459     // convert "/"s to "."s

   460     private String slashesToDots(String str) {

   461         return str.replace(separator != null ? separator : "/", ".");

   462     }

   463 

   464     // initialize file system Nodes

   465     private void initNodes() throws IOException {

   466         // same package prefix may exist in mutliple modules. This Map

   467         // is filled by walking "jdk modules" directory recursively!

   468         Map<String, List<String>> packageToModules = new HashMap<>();

   469 

   470         try (DirectoryStream<Path> stream = Files.newDirectoryStream(SystemImages.explodedModulesDir())) {

   471             for (Path module : stream) {

   472                 if (Files.isDirectory(module)) {

   473                     String moduleName = module.getFileName().toString();

   474                     // make sure "/modules/<moduleName>" is created

   475                     findModulesNode(MODULES + moduleName);

   476 

   477                     Files.walk(module).filter(Files::isDirectory).forEach((p) -> {

   478                         p = module.relativize(p);

   479                         String pkgName = slashesToDots(p.toString());

   480                         // skip META-INFO and empty strings

   481                         if (!pkgName.isEmpty() && !pkgName.startsWith("META-INF")) {

   482                             List<String> moduleNames = packageToModules.get(pkgName);

   483                             if (moduleNames == null) {

   484                                 moduleNames = new ArrayList<>();

   485                                 packageToModules.put(pkgName, moduleNames);

   486                             }

   487                             moduleNames.add(moduleName);

   488                         }

   489                     });

   490                 }

   491             }

   492         }

   493 

   494         // create "/modules" directory

   495         // "nodes" map contains only /modules/<foo> nodes only so far and so add all as children of /modules

   496         DirNode modulesDir = new DirNode("/modules", new ArrayList<>(nodes.values()));

   497         nodes.put(modulesDir.getName(), modulesDir);

   498 

   499         // create children under "/packages"

   500         List<Node> packagesChildren = new ArrayList<>(packageToModules.size());

   501         for (Map.Entry<String, List<String>> entry : packageToModules.entrySet()) {

   502             String pkgName = entry.getKey();

   503             List<String> moduleNameList = entry.getValue();

   504             List<Node> moduleLinkNodes = new ArrayList<>(moduleNameList.size());

   505             for (String moduleName : moduleNameList) {

   506                 Node moduleNode = findModulesNode(MODULES + moduleName);

   507                 LinkNode linkNode = new LinkNode(PACKAGES + pkgName + "/" + moduleName, moduleNode);

   508                 nodes.put(linkNode.getName(), linkNode);

   509                 moduleLinkNodes.add(linkNode);

   510             }

   511 

   512             DirNode pkgDir = new DirNode(PACKAGES + pkgName, moduleLinkNodes);

   513             nodes.put(pkgDir.getName(), pkgDir);

   514             packagesChildren.add(pkgDir);

   515         }

   516 

   517         // "/packages" dir

   518         DirNode packagesDir = new DirNode("/packages", packagesChildren);

   519         nodes.put(packagesDir.getName(), packagesDir);

   520 

   521         // finally "/" dir!

   522         List<Node> rootChildren = new ArrayList<>();

   523         rootChildren.add(modulesDir);

   524         rootChildren.add(packagesDir);

   525         DirNode root = new DirNode("/", rootChildren);

   526         nodes.put(root.getName(), root);

   527     }

   528 }