1 /*
2 * Copyright (c) 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.internal.jmod;
27
28 import java.io.BufferedInputStream;
29 import java.io.IOException;
30 import java.io.InputStream;
31 import java.nio.file.Files;
32 import java.nio.file.Path;
33 import java.util.stream.Stream;
34 import java.util.zip.ZipEntry;
35 import java.util.zip.ZipFile;
36
37 /**
38 * Helper class to read JMOD file
39 */
40 public class JmodFile implements AutoCloseable {
41 // jmod magic number and version number
42 public static final int JMOD_MAJOR_VERSION = 0x01;
43 public static final int JMOD_MINOR_VERSION = 0x00;
44 public static final byte[] JMOD_MAGIC_NUMBER = {
45 0x4A, 0x4D, /* JM */
46 JMOD_MAJOR_VERSION, JMOD_MINOR_VERSION, /* version 1.0 */
47 };
48
49 public static void checkMagic(Path file) throws IOException {
50 try (InputStream in = Files.newInputStream(file);
51 BufferedInputStream bis = new BufferedInputStream(in)) {
52 // validate the header
53 byte[] magic = new byte[4];
54 bis.read(magic);
55 if (magic[0] != JMOD_MAGIC_NUMBER[0] ||
56 magic[1] != JMOD_MAGIC_NUMBER[1]) {
57 throw new IOException("Invalid jmod file: " + file.toString());
58 }
59 if (magic[2] > JMOD_MAJOR_VERSION ||
60 (magic[2] == JMOD_MAJOR_VERSION && magic[3] > JMOD_MINOR_VERSION)) {
61 throw new IOException("Unsupported jmod version: " +
62 magic[2] + "." + magic[3] + " in " + file.toString());
63 }
64 }
65 }
66
67 /**
68 * JMOD sections
69 */
70 public static enum Section {
71 NATIVE_LIBS("native"),
72 NATIVE_CMDS("bin"),
73 CLASSES("classes"),
74 CONFIG("conf"),
75 HEADER_FILES("include"),
76 MAN_PAGES("man");
77
78 private final String jmodDir;
79 private Section(String jmodDir) {
80 this.jmodDir = jmodDir;
81 }
82
83 /**
84 * Returns the directory name in the JMOD file corresponding to
85 * this section
86 */
87 public String jmodDir() { return jmodDir; }
88
89 }
90
91 /**
92 * JMOD file entry.
93 *
94 * Each entry corresponds to a ZipEntry whose name is:
95 * Section::jmodDir + '/' + name
96 */
97 public static class Entry {
98 private final ZipEntry zipEntry;
99 private final Section section;
100 private final String name;
101
102 private Entry(ZipEntry e) {
103 String name = e.getName();
104 int i = name.indexOf('/');
105 if (i <= 1) {
106 throw new RuntimeException("invalid jmod entry: " + name);
107 }
108
109 this.zipEntry = e;
110 this.section = section(name);
111 this.name = name.substring(i+1);
112 }
113
114 /**
115 * Returns the section of this entry.
116 */
117 public Section section() {
118 return section;
119 }
120
121 /**
122 * Returns the name of this entry.
123 */
124 public String name() {
125 return name;
126 }
127
128 /**
129 * Returns the size of this entry.
130 */
131 public long size() {
132 return zipEntry.getSize();
133 }
134
135 public ZipEntry zipEntry() {
136 return zipEntry;
137 }
138
139 @Override
140 public String toString() {
141 return section.jmodDir() + "/" + name;
142 }
143
144 static Section section(String name) {
145 int i = name.indexOf('/');
146 String s = name.substring(0, i);
147 switch (s) {
148 case "native":
149 return Section.NATIVE_LIBS;
150 case "bin":
151 return Section.NATIVE_CMDS;
152 case "classes":
153 return Section.CLASSES;
154 case "conf":
155 return Section.CONFIG;
156 case "include":
157 return Section.HEADER_FILES;
158 case "man":
159 return Section.MAN_PAGES;
160 default:
161 throw new IllegalArgumentException("invalid section: " + s);
162 }
163 }
164 }
165
166 private final Path file;
167 private final ZipFile zipfile;
168
169 /**
170 * Constructs a {@code JmodFile} from a given path.
171 */
172 public JmodFile(Path file) throws IOException {
173 checkMagic(file);
174 this.file = file;
175 this.zipfile = new ZipFile(file.toFile());
176 }
177
178 /**
179 * Returns the {@code Entry} for a resource in a JMOD file section
180 * or {@code null} if not found.
181 */
182 public Entry getEntry(Section section, String name) {
183 String entry = section.jmodDir() + "/" + name;
184 ZipEntry ze = zipfile.getEntry(entry);
185 return (ze != null) ? new Entry(ze) : null;
186 }
187
188 /**
189 * Opens an {@code InputStream} for reading the named entry of the given
190 * section in this jmod file.
191 *
192 * @throws IOException if the named entry is not found, or I/O error
193 * occurs when reading it
194 */
195 public InputStream getInputStream(Section section, String name)
196 throws IOException
197 {
198 String entry = section.jmodDir() + "/" + name;
199 ZipEntry e = zipfile.getEntry(entry);
200 if (e == null) {
201 throw new IOException(name + " not found: " + file);
202 }
203 return zipfile.getInputStream(e);
204 }
205
206 /**
207 * Opens an {@code InputStream} for reading an entry in the JMOD file.
208 *
209 * @throws IOException if an I/O error occurs
210 */
211 public InputStream getInputStream(Entry entry) throws IOException {
212 return zipfile.getInputStream(entry.zipEntry());
213 }
214
215 /**
216 * Returns a stream of non-directory entries in this jmod file.
217 */
218 public Stream<Entry> stream() {
219 return zipfile.stream()
220 .filter(e -> !e.isDirectory())
221 .map(Entry::new);
222 }
223
224 @Override
225 public void close() throws IOException {
226 if (zipfile != null) {
227 zipfile.close();
228 }
229 }
230 }