1 /*
2 * Copyright (c) 2014, 2022, 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.ByteArrayInputStream;
28 import java.io.IOException;
29 import java.io.InputStream;
30 import java.io.OutputStream;
31 import java.nio.ByteBuffer;
32 import java.nio.channels.Channels;
33 import java.nio.channels.FileChannel;
34 import java.nio.channels.NonWritableChannelException;
35 import java.nio.channels.ReadableByteChannel;
36 import java.nio.channels.SeekableByteChannel;
37 import java.nio.file.ClosedFileSystemException;
38 import java.nio.file.CopyOption;
39 import java.nio.file.DirectoryStream;
40 import java.nio.file.FileStore;
41 import java.nio.file.FileSystem;
42 import java.nio.file.FileSystemException;
43 import java.nio.file.InvalidPathException;
44 import java.nio.file.LinkOption;
45 import java.nio.file.NoSuchFileException;
46 import java.nio.file.NotDirectoryException;
47 import java.nio.file.OpenOption;
48 import java.nio.file.Path;
49 import java.nio.file.PathMatcher;
50 import java.nio.file.ReadOnlyFileSystemException;
51 import java.nio.file.StandardOpenOption;
52 import java.nio.file.WatchService;
53 import java.nio.file.attribute.FileAttribute;
54 import java.nio.file.attribute.FileTime;
55 import java.nio.file.attribute.UserPrincipalLookupService;
56 import java.nio.file.spi.FileSystemProvider;
57 import java.util.ArrayList;
58 import java.util.Arrays;
59 import java.util.Collections;
60 import java.util.HashSet;
61 import java.util.Iterator;
62 import java.util.Map;
63 import java.util.Objects;
64 import java.util.Set;
65 import java.util.regex.Pattern;
66 import jdk.internal.jimage.ImageReader.Node;
67 import static java.util.stream.Collectors.toList;
68
69 /**
70 * jrt file system implementation built on System jimage files.
71 *
72 * @implNote This class needs to maintain JDK 8 source compatibility.
73 *
74 * It is used internally in the JDK to implement jimage/jrtfs access,
75 * but also compiled and delivered as part of the jrtfs.jar to support access
76 * to the jimage file provided by the shipped JDK by tools running on JDK 8.
77 */
78 class JrtFileSystem extends FileSystem {
79
80 private final JrtFileSystemProvider provider;
81 private final JrtPath rootPath = new JrtPath(this, "/");
82 private volatile boolean isOpen;
83 private volatile boolean isClosable;
84 private SystemImage image;
85
86 JrtFileSystem(JrtFileSystemProvider provider, Map<String, ?> env)
87 throws IOException
88 {
89 this.provider = provider;
90 this.image = SystemImage.open(); // open image file
91 this.isOpen = true;
92 this.isClosable = env != null;
93 }
94
95 // FileSystem method implementations
96 @Override
97 public boolean isOpen() {
98 return isOpen;
99 }
100
101 @Override
102 public void close() throws IOException {
103 if (!isClosable)
104 throw new UnsupportedOperationException();
105 cleanup();
106 }
107
108 @Override
109 public FileSystemProvider provider() {
110 return provider;
111 }
112
113 @Override
114 public Iterable<Path> getRootDirectories() {
115 return Collections.singleton(getRootPath());
116 }
117
118 @Override
119 public JrtPath getPath(String first, String... more) {
120 if (more.length == 0) {
121 return new JrtPath(this, first);
122 }
123 StringBuilder sb = new StringBuilder();
124 sb.append(first);
125 for (String path : more) {
126 if (!path.isEmpty()) {
127 if (sb.length() > 0) {
128 sb.append('/');
129 }
130 sb.append(path);
131 }
132 }
133 return new JrtPath(this, sb.toString());
134 }
135
136 @Override
137 public final boolean isReadOnly() {
138 return true;
139 }
140
141 @Override
142 public final UserPrincipalLookupService getUserPrincipalLookupService() {
143 throw new UnsupportedOperationException();
144 }
145
146 @Override
147 public final WatchService newWatchService() {
148 throw new UnsupportedOperationException();
149 }
150
151 @Override
152 public final Iterable<FileStore> getFileStores() {
153 return Collections.singleton(getFileStore(getRootPath()));
154 }
155
156 private static final Set<String> supportedFileAttributeViews
157 = Collections.unmodifiableSet(
158 new HashSet<String>(Arrays.asList("basic", "jrt")));
159
160 @Override
161 public final Set<String> supportedFileAttributeViews() {
162 return supportedFileAttributeViews;
163 }
164
165 @Override
166 public final String toString() {
167 return "jrt:/";
168 }
169
170 @Override
171 public final String getSeparator() {
172 return "/";
173 }
174
175 @Override
176 public PathMatcher getPathMatcher(String syntaxAndInput) {
177 int pos = syntaxAndInput.indexOf(':');
178 if (pos <= 0) {
179 throw new IllegalArgumentException();
180 }
181 String syntax = syntaxAndInput.substring(0, pos);
182 String input = syntaxAndInput.substring(pos + 1);
183 String expr;
184 if (syntax.equalsIgnoreCase("glob")) {
185 expr = JrtUtils.toRegexPattern(input);
186 } else if (syntax.equalsIgnoreCase("regex")) {
187 expr = input;
188 } else {
189 throw new UnsupportedOperationException("Syntax '" + syntax
190 + "' not recognized");
191 }
192 // return matcher
193 final Pattern pattern = Pattern.compile(expr);
194 return (Path path) -> pattern.matcher(path.toString()).matches();
195 }
196
197 JrtPath resolveLink(JrtPath path) throws IOException {
198 Node node = checkNode(path);
199 if (node.isLink()) {
200 node = node.resolveLink();
201 return new JrtPath(this, node.getName()); // TBD, normalized?
202 }
203 return path;
204 }
205
206 JrtFileAttributes getFileAttributes(JrtPath path, LinkOption... options)
207 throws IOException {
208 Node node = checkNode(path);
209 if (node.isLink() && followLinks(options)) {
210 return new JrtFileAttributes(node.resolveLink(true));
211 }
212 return new JrtFileAttributes(node);
213 }
214
215 /**
216 * returns the list of child paths of the given directory "path"
217 *
218 * @param path name of the directory whose content is listed
219 * @return iterator for child paths of the given directory path
220 */
221 Iterator<Path> iteratorOf(JrtPath path, DirectoryStream.Filter<? super Path> filter)
222 throws IOException {
223 Node node = checkNode(path).resolveLink(true);
224 if (!node.isDirectory()) {
225 throw new NotDirectoryException(path.getName());
226 }
227 if (filter == null) {
228 return node.getChildren()
229 .stream()
230 .map(child -> (Path)(path.resolve(new JrtPath(this, child.getNameString()).getFileName())))
231 .iterator();
232 }
233 return node.getChildren()
234 .stream()
235 .map(child -> (Path)(path.resolve(new JrtPath(this, child.getNameString()).getFileName())))
236 .filter(p -> { try { return filter.accept(p);
237 } catch (IOException x) {}
238 return false;
239 })
240 .iterator();
241 }
242
243 // returns the content of the file resource specified by the path
244 byte[] getFileContent(JrtPath path) throws IOException {
245 Node node = checkNode(path);
246 if (node.isDirectory()) {
247 throw new FileSystemException(path + " is a directory");
248 }
249 //assert node.isResource() : "resource node expected here";
250 return image.getResource(node);
251 }
252
253 /////////////// Implementation details below this point //////////
254
255 // static utility methods
256 static ReadOnlyFileSystemException readOnly() {
257 return new ReadOnlyFileSystemException();
258 }
259
260 // do the supplied options imply that we have to chase symlinks?
261 static boolean followLinks(LinkOption... options) {
262 if (options != null) {
263 for (LinkOption lo : options) {
264 Objects.requireNonNull(lo);
265 if (lo == LinkOption.NOFOLLOW_LINKS) {
266 return false;
267 } else {
268 throw new AssertionError("should not reach here");
269 }
270 }
271 }
272 return true;
273 }
274
275 // check that the options passed are supported by (read-only) jrt file system
276 static void checkOptions(Set<? extends OpenOption> options) {
277 // check for options of null type and option is an instance of StandardOpenOption
278 for (OpenOption option : options) {
279 Objects.requireNonNull(option);
280 if (!(option instanceof StandardOpenOption)) {
281 throw new IllegalArgumentException(
282 "option class: " + option.getClass());
283 }
284 }
285 if (options.contains(StandardOpenOption.WRITE) ||
286 options.contains(StandardOpenOption.APPEND)) {
287 throw readOnly();
288 }
289 }
290
291 // clean up this file system - called from finalize and close
292 synchronized void cleanup() throws IOException {
293 if (isOpen) {
294 isOpen = false;
295 image.close();
296 image = null;
297 }
298 }
299
300 // These methods throw read only file system exception
301 final void setTimes(JrtPath jrtPath, FileTime mtime, FileTime atime, FileTime ctime)
302 throws IOException {
303 throw readOnly();
304 }
305
306 // These methods throw read only file system exception
307 final void createDirectory(JrtPath jrtPath, FileAttribute<?>... attrs) throws IOException {
308 throw readOnly();
309 }
310
311 final void deleteFile(JrtPath jrtPath, boolean failIfNotExists)
312 throws IOException {
313 throw readOnly();
314 }
315
316 final OutputStream newOutputStream(JrtPath jrtPath, OpenOption... options)
317 throws IOException {
318 throw readOnly();
319 }
320
321 final void copyFile(boolean deletesrc, JrtPath srcPath, JrtPath dstPath, CopyOption... options)
322 throws IOException {
323 throw readOnly();
324 }
325
326 final FileChannel newFileChannel(JrtPath path,
327 Set<? extends OpenOption> options,
328 FileAttribute<?>... attrs)
329 throws IOException {
330 throw new UnsupportedOperationException("newFileChannel");
331 }
332
333 final InputStream newInputStream(JrtPath path) throws IOException {
334 return new ByteArrayInputStream(getFileContent(path));
335 }
336
337 final SeekableByteChannel newByteChannel(JrtPath path,
338 Set<? extends OpenOption> options,
339 FileAttribute<?>... attrs)
340 throws IOException {
341 checkOptions(options);
342
343 byte[] buf = getFileContent(path);
344 final ReadableByteChannel rbc
345 = Channels.newChannel(new ByteArrayInputStream(buf));
346 final long size = buf.length;
347 return new SeekableByteChannel() {
348 long read = 0;
349
350 @Override
351 public boolean isOpen() {
352 return rbc.isOpen();
353 }
354
355 @Override
356 public long position() throws IOException {
357 return read;
358 }
359
360 @Override
361 public SeekableByteChannel position(long pos)
362 throws IOException {
363 throw new UnsupportedOperationException();
364 }
365
366 @Override
367 public int read(ByteBuffer dst) throws IOException {
368 int n = rbc.read(dst);
369 if (n > 0) {
370 read += n;
371 }
372 return n;
373 }
374
375 @Override
376 public SeekableByteChannel truncate(long size)
377 throws IOException {
378 throw new NonWritableChannelException();
379 }
380
381 @Override
382 public int write(ByteBuffer src) throws IOException {
383 throw new NonWritableChannelException();
384 }
385
386 @Override
387 public long size() throws IOException {
388 return size;
389 }
390
391 @Override
392 public void close() throws IOException {
393 rbc.close();
394 }
395 };
396 }
397
398 final JrtFileStore getFileStore(JrtPath path) {
399 return new JrtFileStore(path);
400 }
401
402 final void ensureOpen() throws IOException {
403 if (!isOpen()) {
404 throw new ClosedFileSystemException();
405 }
406 }
407
408 final JrtPath getRootPath() {
409 return rootPath;
410 }
411
412 boolean isSameFile(JrtPath path1, JrtPath path2) throws IOException {
413 return checkNode(path1) == checkNode(path2);
414 }
415
416 boolean isLink(JrtPath path) throws IOException {
417 return checkNode(path).isLink();
418 }
419
420 boolean exists(JrtPath path) throws IOException {
421 try {
422 checkNode(path);
423 } catch (NoSuchFileException exp) {
424 return false;
425 }
426 return true;
427 }
428
429 boolean isDirectory(JrtPath path, boolean resolveLinks)
430 throws IOException {
431 Node node = checkNode(path);
432 return resolveLinks && node.isLink()
433 ? node.resolveLink(true).isDirectory()
434 : node.isDirectory();
435 }
436
437 JrtPath toRealPath(JrtPath path, LinkOption... options)
438 throws IOException {
439 Node node = checkNode(path);
440 if (followLinks(options) && node.isLink()) {
441 node = node.resolveLink();
442 }
443 // image node holds the real/absolute path name
444 return new JrtPath(this, node.getName(), true);
445 }
446
447 private Node lookup(String path) {
448 try {
449 return image.findNode(path);
450 } catch (RuntimeException | IOException ex) {
451 throw new InvalidPathException(path, ex.toString());
452 }
453 }
454
455 private Node lookupSymbolic(String path) {
456 int i = 1;
457 while (i < path.length()) {
458 i = path.indexOf('/', i);
459 if (i == -1) {
460 break;
461 }
462 String prefix = path.substring(0, i);
463 Node node = lookup(prefix);
464 if (node == null) {
465 break;
466 }
467 if (node.isLink()) {
468 Node link = node.resolveLink(true);
469 // resolved symbolic path concatenated to the rest of the path
470 String resPath = link.getName() + path.substring(i);
471 node = lookup(resPath);
472 return node != null ? node : lookupSymbolic(resPath);
473 }
474 i++;
475 }
476 return null;
477 }
478
479 Node checkNode(JrtPath path) throws IOException {
480 ensureOpen();
481 String p = path.getResolvedPath();
482 Node node = lookup(p);
483 if (node == null) {
484 node = lookupSymbolic(p);
485 if (node == null) {
486 throw new NoSuchFileException(p);
487 }
488 }
489 return node;
490 }
491 }