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