1 /*
2 * Copyright (c) 2015, 2016, 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.module;
26
27 import java.io.Closeable;
28 import java.io.File;
29 import java.io.IOError;
30 import java.io.IOException;
31 import java.io.InputStream;
32 import java.io.UncheckedIOException;
33 import java.lang.module.ModuleDescriptor;
34 import java.lang.module.ModuleReader;
35 import java.lang.module.ModuleReference;
36 import java.net.MalformedURLException;
37 import java.net.URI;
38 import java.net.URL;
39 import java.nio.ByteBuffer;
40 import java.nio.file.Files;
41 import java.nio.file.Path;
42 import java.nio.file.Paths;
43 import java.util.ArrayList;
44 import java.util.Collections;
45 import java.util.HashMap;
46 import java.util.HashSet;
47 import java.util.List;
48 import java.util.Map;
49 import java.util.Optional;
50 import java.util.Set;
51 import java.util.jar.JarEntry;
52 import java.util.jar.JarFile;
53
54 import jdk.internal.loader.Resource;
55 import jdk.internal.misc.JavaLangModuleAccess;
56 import jdk.internal.misc.SharedSecrets;
57 import sun.net.www.ParseUtil;
58
59
60 /**
61 * Provides support for patching modules in the boot layer with -Xpatch.
62 */
63
64 public final class ModulePatcher {
65
66 private static final JavaLangModuleAccess JLMA
67 = SharedSecrets.getJavaLangModuleAccess();
68
69 // the prefix of the system properties that encode the value of -Xpatch
70 private static final String PATCH_PROPERTY_PREFIX = "jdk.launcher.patch.";
71
72 // module name -> sequence of patches (directories or JAR files)
73 private static final Map<String, List<Path>> PATCH_MAP = decodeProperties();
74
75 private ModulePatcher() { }
76
77
78 /**
79 * Decodes the values of -Xpatch options, returning a Map of module name to
80 * list of file paths.
81 *
82 * @throws IllegalArgumentException if the the module name is missing or
83 * -Xpatch is used more than once to patch the same module
84 */
85 private static Map<String, List<Path>> decodeProperties() {
86
87 int index = 0;
88 String value = System.getProperty(PATCH_PROPERTY_PREFIX + index);
89 if (value == null)
90 return Collections.emptyMap(); // -Xpatch not specified
91
92 Map<String, List<Path>> map = new HashMap<>();
93 while (value != null) {
94 int pos = value.indexOf('=');
95
96 if (pos == -1 && index > 0)
97 throwIAE("Unable to parse: " + value);
98
99 if (pos == 0)
100 throwIAE("Missing module name: " + value);
101
102 if (pos > 0) {
103
104 // new format: <module>=<file>(:<file>)*
105
106 String mn = value.substring(0, pos);
107 List<Path> list = map.get(mn);
108 if (list != null)
109 throwIAE("Module " + mn + " specified more than once");
110 list = new ArrayList<>();
111 map.put(mn, list);
112
113 String paths = value.substring(pos+1);
114 for (String path : paths.split(File.pathSeparator)) {
115 if (!path.isEmpty()) {
116 list.add(Paths.get(path));
117 }
118 }
119
120 } else {
121
122 // old format: <dir>(:<dir>)*
123
124 assert index == 0; // old format only allowed in first -Xpatch
125
126 String[] dirs = value.split(File.pathSeparator);
127 for (String d : dirs) {
128 if (d.length() > 0) {
129 Path top = Paths.get(d);
130 try {
131 Files.list(top).forEach(e -> {
132 String mn = e.getFileName().toString();
133 Path dir = top.resolve(mn);
134 map.computeIfAbsent(mn, k -> new ArrayList<>())
135 .add(dir);
136 });
137 } catch (IOException ignore) { }
138 }
139 }
140
141 }
142
143
144 index++;
145 value = System.getProperty(PATCH_PROPERTY_PREFIX + index);
146 }
147
148 return map;
149 }
150
151
152 /**
153 * Returns a module reference that interposes on the given module if
154 * needed. If there are no patches for the given module then the module
155 * reference is simply returned. Otherwise the patches for the module
156 * are scanned (to find any new concealed packages) and a new module
157 * reference is returned.
158 *
159 * @throws UncheckedIOException if an I/O error is detected
160 */
161 public static ModuleReference interposeIfNeeded(ModuleReference mref) {
162
163 ModuleDescriptor descriptor = mref.descriptor();
164 String mn = descriptor.name();
165
166 // if there are no patches for the module then nothing to do
167 List<Path> paths = PATCH_MAP.get(mn);
168 if (paths == null)
169 return mref;
170
171
172 // scan the JAR file or directory tree to get the set of packages
173 Set<String> packages = new HashSet<>();
174 try {
175 for (Path file : paths) {
176 if (Files.isRegularFile(file)) {
177
178 // JAR file
179 try (JarFile jf = new JarFile(file.toFile())) {
180 jf.stream()
181 .filter(e -> e.getName().endsWith(".class"))
182 .map(e -> toPackageName(file, e))
183 .filter(pn -> pn.length() > 0)
184 .forEach(packages::add);
185 }
186
187 } else if (Files.isDirectory(file)) {
188
189 // exploded directory
190 Path top = file;
191 Files.find(top, Integer.MAX_VALUE,
192 ((path, attrs) -> attrs.isRegularFile() &&
193 path.toString().endsWith(".class")))
194 .map(path -> toPackageName(top, path))
195 .filter(pn -> pn.length() > 0)
196 .forEach(packages::add);
197
198 }
199 }
200
201 } catch (IOException ioe) {
202 throw new UncheckedIOException(ioe);
203 }
204
205 // if there are new packages then we need a new ModuleDescriptor
206 Set<String> original = descriptor.packages();
207 packages.addAll(original);
208 if (packages.size() > original.size()) {
209 descriptor = JLMA.newModuleDescriptor(descriptor, packages);
210 }
211
212 // return a new module reference
213 URI location = mref.location().orElse(null);
214 return new ModuleReference(descriptor, location,
215 () -> new PatchedModuleReader(paths, mref));
216
217 }
218
219
220 /**
221 * A ModuleReader that reads resources from a patched module.
222 *
223 * This class is public so as to expose the findResource method to the
224 * built-in class loaders and avoid locating the resource twice during
225 * class loading (once to locate the resource, the second to gets the
226 * URL for the CodeSource).
227 */
228 public static class PatchedModuleReader implements ModuleReader {
229 private final List<ResourceFinder> finders;
230 private final ModuleReference mref;
231 private final URL delegateCodeSourceURL;
232 private volatile ModuleReader delegate;
233
234 /**
235 * Creates the ModuleReader to reads resources a patched module.
236 */
237 PatchedModuleReader(List<Path> patches, ModuleReference mref) {
238 List<ResourceFinder> finders = new ArrayList<>();
239 boolean initialized = false;
240 try {
241 for (Path file : patches) {
242 if (Files.isRegularFile(file)) {
243 finders.add(new JarResourceFinder(file));
244 } else {
245 finders.add(new ExplodedResourceFinder(file));
246 }
247 }
248 initialized = true;
249 } catch (IOException ioe) {
250 throw new UncheckedIOException(ioe);
251 } finally {
252 // close all ResourceFinder in the event of an error
253 if (!initialized) closeAll(finders);
254 }
255
256 this.finders = finders;
257 this.mref = mref;
258 this.delegateCodeSourceURL = codeSourceURL(mref);
259 }
260
261 /**
262 * Closes all resource finders.
263 */
264 private static void closeAll(List<ResourceFinder> finders) {
265 for (ResourceFinder finder : finders) {
266 try { finder.close(); } catch (IOException ioe) { }
267 }
268 }
269
270 /**
271 * Returns the code source URL for the given module.
272 */
273 private static URL codeSourceURL(ModuleReference mref) {
274 try {
275 Optional<URI> ouri = mref.location();
276 if (ouri.isPresent())
277 return ouri.get().toURL();
278 } catch (MalformedURLException e) { }
279 return null;
280 }
281
282 /**
283 * Returns the ModuleReader to delegate to when the resource is not
284 * found in a patch location.
285 */
286 private ModuleReader delegate() throws IOException {
287 ModuleReader r = delegate;
288 if (r == null) {
289 synchronized (this) {
290 r = delegate;
291 if (r == null) {
292 delegate = r = mref.open();
293 }
294 }
295 }
296 return r;
297 }
298
299 /**
300 * Finds a resources in the patch locations. Returns null if not found.
301 */
302 private Resource findResourceInPatch(String name) throws IOException {
303 for (ResourceFinder finder : finders) {
304 Resource r = finder.find(name);
305 if (r != null)
306 return r;
307 }
308 return null;
309 }
310
311 /**
312 * Finds a resource of the given name in the patched module.
313 */
314 public Resource findResource(String name) throws IOException {
315
316 // patch locations
317 Resource r = findResourceInPatch(name);
318 if (r != null)
319 return r;
320
321 // original module
322 ByteBuffer bb = delegate().read(name).orElse(null);
323 if (bb == null)
324 return null;
325
326 return new Resource() {
327 private <T> T shouldNotGetHere(Class<T> type) {
328 throw new InternalError("should not get here");
329 }
330 @Override
331 public String getName() {
332 return shouldNotGetHere(String.class);
333 }
334 @Override
335 public URL getURL() {
336 return shouldNotGetHere(URL.class);
337 }
338 @Override
339 public URL getCodeSourceURL() {
340 return delegateCodeSourceURL;
341 }
342 @Override
343 public ByteBuffer getByteBuffer() throws IOException {
344 return bb;
345 }
346 @Override
347 public InputStream getInputStream() throws IOException {
348 return shouldNotGetHere(InputStream.class);
349 }
350 @Override
351 public int getContentLength() throws IOException {
352 return shouldNotGetHere(int.class);
353 }
354 };
355 }
356
357 @Override
358 public Optional<URI> find(String name) throws IOException {
359 Resource r = findResourceInPatch(name);
360 if (r != null) {
361 URI uri = URI.create(r.getURL().toString());
362 return Optional.of(uri);
363 } else {
364 return delegate().find(name);
365 }
366 }
367
368 @Override
369 public Optional<InputStream> open(String name) throws IOException {
370 Resource r = findResourceInPatch(name);
371 if (r != null) {
372 return Optional.of(r.getInputStream());
373 } else {
374 return delegate().open(name);
375 }
376 }
377
378 @Override
379 public Optional<ByteBuffer> read(String name) throws IOException {
380 Resource r = findResourceInPatch(name);
381 if (r != null) {
382 ByteBuffer bb = r.getByteBuffer();
383 assert !bb.isDirect();
384 return Optional.of(bb);
385 } else {
386 return delegate().read(name);
387 }
388 }
389
390 @Override
391 public void release(ByteBuffer bb) {
392 if (bb.isDirect()) {
393 try {
394 delegate().release(bb);
395 } catch (IOException ioe) {
396 throw new InternalError(ioe);
397 }
398 }
399 }
400
401 @Override
402 public void close() throws IOException {
403 closeAll(finders);
404 delegate().close();
405 }
406 }
407
408
409 /**
410 * A resource finder that find resources in a patch location.
411 */
412 private static interface ResourceFinder extends Closeable {
413 Resource find(String name) throws IOException;
414 }
415
416
417 /**
418 * A ResourceFinder that finds resources in a JAR file.
419 */
420 private static class JarResourceFinder implements ResourceFinder {
421 private final JarFile jf;
422 private final URL csURL;
423
424 JarResourceFinder(Path path) throws IOException {
425 this.jf = new JarFile(path.toFile());
426 this.csURL = path.toUri().toURL();
427 }
428
429 @Override
430 public void close() throws IOException {
431 jf.close();
432 }
433
434 @Override
435 public Resource find(String name) throws IOException {
436 JarEntry entry = jf.getJarEntry(name);
437 if (entry == null)
438 return null;
439
440 return new Resource() {
441 @Override
442 public String getName() {
443 return name;
444 }
445 @Override
446 public URL getURL() {
447 String encodedPath = ParseUtil.encodePath(name, false);
448 try {
449 return new URL("jar:" + csURL + "!/" + encodedPath);
450 } catch (MalformedURLException e) {
451 return null;
452 }
453 }
454 @Override
455 public URL getCodeSourceURL() {
456 return csURL;
457 }
458 @Override
459 public ByteBuffer getByteBuffer() throws IOException {
460 byte[] bytes = getInputStream().readAllBytes();
461 return ByteBuffer.wrap(bytes);
462 }
463 @Override
464 public InputStream getInputStream() throws IOException {
465 return jf.getInputStream(entry);
466 }
467 @Override
468 public int getContentLength() throws IOException {
469 long size = entry.getSize();
470 return (size > Integer.MAX_VALUE) ? -1 : (int) size;
471 }
472 };
473 }
474 }
475
476
477 /**
478 * A ResourceFinder that finds resources on the file system.
479 */
480 private static class ExplodedResourceFinder implements ResourceFinder {
481 private final Path dir;
482
483 ExplodedResourceFinder(Path dir) {
484 this.dir = dir;
485 }
486
487 @Override
488 public void close() { }
489
490 @Override
491 public Resource find(String name) throws IOException {
492 Path file = Paths.get(name.replace('/', File.separatorChar));
493 if (file.getRoot() == null) {
494 file = dir.resolve(file);
495 } else {
496 // drop the root component so that the resource is
497 // located relative to the module directory
498 int n = file.getNameCount();
499 if (n == 0)
500 return null;
501 file = dir.resolve(file.subpath(0, n));
502 }
503
504 if (Files.isRegularFile(file)) {
505 return newResource(name, dir, file);
506 } else {
507 return null;
508 }
509 }
510
511 private Resource newResource(String name, Path top, Path file) {
512 return new Resource() {
513 @Override
514 public String getName() {
515 return name;
516 }
517 @Override
518 public URL getURL() {
519 try {
520 return file.toUri().toURL();
521 } catch (IOException | IOError e) {
522 return null;
523 }
524 }
525 @Override
526 public URL getCodeSourceURL() {
527 try {
528 return top.toUri().toURL();
529 } catch (IOException | IOError e) {
530 return null;
531 }
532 }
533 @Override
534 public ByteBuffer getByteBuffer() throws IOException {
535 return ByteBuffer.wrap(Files.readAllBytes(file));
536 }
537 @Override
538 public InputStream getInputStream() throws IOException {
539 return Files.newInputStream(file);
540 }
541 @Override
542 public int getContentLength() throws IOException {
543 long size = Files.size(file);
544 return (size > Integer.MAX_VALUE) ? -1 : (int)size;
545 }
546 };
547 }
548 }
549
550
551 /**
552 * Derives a package name from a file path to a .class file.
553 */
554 private static String toPackageName(Path top, Path file) {
555 Path entry = top.relativize(file);
556 Path parent = entry.getParent();
557 if (parent == null) {
558 return warnUnnamedPackage(top, entry.toString());
559 } else {
560 return parent.toString().replace(File.separatorChar, '.');
561 }
562 }
563
564 /**
565 * Derives a package name from the name of an entry in a JAR file.
566 */
567 private static String toPackageName(Path file, JarEntry entry) {
568 String name = entry.getName();
569 int index = name.lastIndexOf("/");
570 if (index == -1) {
571 return warnUnnamedPackage(file, name);
572 } else {
573 return name.substring(0, index).replace('/', '.');
574 }
575 }
576
577 private static String warnUnnamedPackage(Path file, String e) {
578 System.err.println("WARNING: " + e + " not allowed in patch: " + file);
579 return "";
580 }
581
582 private static void throwIAE(String msg) {
583 throw new IllegalArgumentException(msg);
584 }
585
586 }