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
26 package jdk.nio.zipfs;
27
28 import java.io.IOException;
29 import java.io.InputStream;
30 import java.lang.Runtime.Version;
31 import java.nio.file.Path;
32 import java.util.Arrays;
33 import java.util.HashMap;
34 import java.util.Map;
35 import java.util.TreeMap;
36 import java.util.function.Consumer;
37 import java.util.function.Function;
38 import java.util.jar.Attributes;
39 import java.util.jar.Manifest;
40
41 /**
42 * Adds aliasing to ZipFileSystem to support multi-release jar files. An alias map
43 * is created by {@link JarFileSystem#createVersionedLinks(int)}. The map is then
44 * consulted when an entry is looked up in {@link JarFileSystem#getEntry(byte[])}
45 * to determine if the entry has a corresponding versioned entry. If so, the
46 * versioned entry is returned.
47 *
48 * @author Steve Drach
49 */
50
51 class JarFileSystem extends ZipFileSystem {
52 private Function<byte[],byte[]> lookup;
53
54 @Override
55 IndexNode getInode(byte[] path) {
56 // check for an alias to a versioned entry
57 byte[] versionedPath = lookup.apply(path);
58 return versionedPath == null ? super.getInode(path) : super.getInode(versionedPath);
59 }
60
61 JarFileSystem(ZipFileSystemProvider provider, Path zfpath, Map<String,?> env)
62 throws IOException {
63 super(provider, zfpath, env);
64 lookup = path -> path; // lookup needs to be set before isMultiReleaseJar is called
65 // because it eventually calls getEntry
66 if (isMultiReleaseJar()) {
67 int version;
68 Object o = env.get("multi-release");
69 if (o instanceof String) {
70 String s = (String)o;
71 if (s.equals("runtime")) {
72 version = Runtime.version().major();
73 } else {
74 version = Integer.parseInt(s);
75 }
76 } else if (o instanceof Integer) {
77 version = (Integer)o;
78 } else if (o instanceof Version) {
79 version = ((Version)o).major();
80 } else {
81 throw new IllegalArgumentException("env parameter must be String, Integer, "
82 + "or Version");
83 }
84 lookup = createVersionedLinks(version < 0 ? 0 : version);
85 setReadOnly();
86 }
87 }
88
89 private boolean isMultiReleaseJar() {
90 try (InputStream is = newInputStream(getBytes("/META-INF/MANIFEST.MF"))) {
91 byte[] b = is.readAllBytes();
92 // Keep this implementation up to date with
93 // JarFile::checkForSpecialAttributes
94 int i = match(MULTIRELEASE_CHARS, b, MULTIRELEASE_LASTOCC,
95 MULTIRELEASE_OPTOSFT);
96 if (i != -1) {
97 i += MULTIRELEASE_CHARS.length;
98 if (i < b.length) {
99 byte c = b[i++];
100 // Check that the value is followed by a newline
101 // and does not have a continuation
102 if (c == '\n' &&
103 (i == b.length || b[i] != ' ')) {
104 return true;
105 } else if (c == '\r') {
106 if (i == b.length) {
107 return true;
108 } else {
109 c = b[i++];
110 if (c == '\n') {
111 if (i == b.length || b[i] != ' ') {
112 return true;
113 }
114 } else if (c != ' ') {
115 return true;
116 }
117 }
118 }
119 }
120 }
121 return false;
122 } catch (IOException x) {
123 return false;
124 }
125 }
126
127 private static final byte[] MULTIRELEASE_CHARS =
128 {'M','U','L','T','I','-','R','E','L','E', 'A', 'S', 'E', ':',
129 ' ', 'T', 'R', 'U', 'E'};
130
131 // The bad character shift for "multi-release: true"
132 private static final byte[] MULTIRELEASE_LASTOCC;
133
134 // The good suffix shift for "multi-release: true"
135 private static final byte[] MULTIRELEASE_OPTOSFT;
136
137 static {
138 MULTIRELEASE_LASTOCC = new byte[64];
139 MULTIRELEASE_OPTOSFT = new byte[19];
140 MULTIRELEASE_LASTOCC[(int)'M' - 32] = 1;
141 MULTIRELEASE_LASTOCC[(int)'I' - 32] = 5;
142 MULTIRELEASE_LASTOCC[(int)'-' - 32] = 6;
143 MULTIRELEASE_LASTOCC[(int)'L' - 32] = 9;
144 MULTIRELEASE_LASTOCC[(int)'A' - 32] = 11;
145 MULTIRELEASE_LASTOCC[(int)'S' - 32] = 12;
146 MULTIRELEASE_LASTOCC[(int)':' - 32] = 14;
147 MULTIRELEASE_LASTOCC[(int)' ' - 32] = 15;
148 MULTIRELEASE_LASTOCC[(int)'T' - 32] = 16;
149 MULTIRELEASE_LASTOCC[(int)'R' - 32] = 17;
150 MULTIRELEASE_LASTOCC[(int)'U' - 32] = 18;
151 MULTIRELEASE_LASTOCC[(int)'E' - 32] = 19;
152 for (int i = 0; i < 17; i++) {
153 MULTIRELEASE_OPTOSFT[i] = 19;
154 }
155 MULTIRELEASE_OPTOSFT[17] = 6;
156 MULTIRELEASE_OPTOSFT[18] = 1;
157 }
158
159 /**
160 * Returns true if the pattern {@code src} is found in {@code b}.
161 * The {@code lastOcc} array is the precomputed bad character shifts.
162 * Since there are no repeated substring in our search strings,
163 * the good suffix shifts can be replaced with a comparison.
164 */
165 private static int match(byte[] src, byte[] b, byte[] lastOcc, byte[] optoSft) {
166 int len = src.length;
167 int last = b.length - len;
168 int i = 0;
169 next:
170 while (i <= last) {
171 for (int j = (len - 1); j >= 0; j--) {
172 byte c = b[i + j];
173 if (c >= ' ' && c <= 'z') {
174 if (c >= 'a') c -= 32; // Canonicalize
175
176 if (c != src[j]) {
177 // no match
178 int badShift = lastOcc[c - 32];
179 i += Math.max(j + 1 - badShift, optoSft[j]);
180 continue next;
181 }
182 } else {
183 // no match, character not valid for name
184 i += len;
185 continue next;
186 }
187 }
188 return i;
189 }
190 return -1;
191 }
192
193 /**
194 * create a map of aliases for versioned entries, for example:
195 * version/PackagePrivate.class -> META-INF/versions/9/version/PackagePrivate.class
196 * version/PackagePrivate.java -> META-INF/versions/9/version/PackagePrivate.java
197 * version/Version.class -> META-INF/versions/10/version/Version.class
198 * version/Version.java -> META-INF/versions/10/version/Version.java
199 *
200 * then wrap the map in a function that getEntry can use to override root
201 * entry lookup for entries that have corresponding versioned entries
202 */
203 private Function<byte[],byte[]> createVersionedLinks(int version) {
204 HashMap<IndexNode,byte[]> aliasMap = new HashMap<>();
205 getVersionMap(version, getInode(getBytes("/META-INF/versions"))).values()
206 .forEach(versionNode -> { // for each META-INF/versions/{n} directory
207 // put all the leaf inodes, i.e. entries, into the alias map
208 // possibly shadowing lower versioned entries
209 walk(versionNode, entryNode -> {
210 byte[] rootName = getRootName(versionNode, entryNode);
211 if (rootName != null) {
212 IndexNode rootNode = getInode(rootName);
213 if (rootNode == null) { // no matching root node, make a virtual one
214 rootNode = IndexNode.keyOf(rootName);
215 }
216 aliasMap.put(rootNode, entryNode.name);
217 }
218 });
219 });
220 return path -> aliasMap.get(IndexNode.keyOf(path));
221 }
222
223 /**
224 * create a sorted version map of version -> inode, for inodes <= max version
225 * 9 -> META-INF/versions/9
226 * 10 -> META-INF/versions/10
227 */
228 private TreeMap<Integer, IndexNode> getVersionMap(int version, IndexNode metaInfVersions) {
229 TreeMap<Integer,IndexNode> map = new TreeMap<>();
230 IndexNode child = metaInfVersions.child;
231 while (child != null) {
232 Integer key = getVersion(child.name, metaInfVersions.name.length + 1);
233 if (key != null && key <= version) {
234 map.put(key, child);
235 }
236 child = child.sibling;
237 }
238 return map;
239 }
240
241 /**
242 * extract the integer version number -- META-INF/versions/9 returns 9
243 */
244 private Integer getVersion(byte[] name, int offset) {
245 try {
246 return Integer.parseInt(getString(Arrays.copyOfRange(name, offset, name.length)));
247 } catch (NumberFormatException x) {
248 // ignore this even though it might indicate issues with the JAR structure
249 return null;
250 }
251 }
252
253 /**
254 * walk the IndexNode tree processing all leaf nodes
255 */
256 private void walk(IndexNode inode, Consumer<IndexNode> process) {
257 if (inode == null) return;
258 if (inode.isDir()) {
259 walk(inode.child, process);
260 } else {
261 process.accept(inode);
262 }
263 walk(inode.sibling, process);
264 }
265
266 /**
267 * extract the root name from a versioned entry name
268 * given inode for META-INF/versions/9/foo/bar.class
269 * and prefix META-INF/versions/9/
270 * returns foo/bar.class
271 */
272 private byte[] getRootName(IndexNode prefix, IndexNode inode) {
273 int offset = prefix.name.length;
274 byte[] fullName = inode.name;
275 return Arrays.copyOfRange(fullName, offset, fullName.length);
276 }
277 }