source: other-projects/trunk/gs3-release-maker/apache-ant-1.6.5/src/main/org/apache/tools/zip/AsiExtraField.java@ 14627

Last change on this file since 14627 was 14627, checked in by oranfry, 17 years ago

initial import of the gs3-release-maker
File size: 8.5 KB
Line 
1/*
2 * Copyright 2001-2002,2004-2005 The Apache Software Foundation
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 * http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 *
16 */
17
18package org.apache.tools.zip;
19
20import java.util.zip.CRC32;
21import java.util.zip.ZipException;
22
23/**
24 * Adds Unix file permission and UID/GID fields as well as symbolic
25 * link handling.
26 *
27 * <p>This class uses the ASi extra field in the format:
28 * <pre>
29 * Value Size Description
30 * ----- ---- -----------
31 * (Unix3) 0x756e Short tag for this extra block type
32 * TSize Short total data size for this block
33 * CRC Long CRC-32 of the remaining data
34 * Mode Short file permissions
35 * SizDev Long symlink'd size OR major/minor dev num
36 * UID Short user ID
37 * GID Short group ID
38 * (var.) variable symbolic link filename
39 * </pre>
40 * taken from appnote.iz (Info-ZIP note, 981119) found at <a
41 * href="ftp://ftp.uu.net/pub/archiving/zip/doc/">ftp://ftp.uu.net/pub/archiving/zip/doc/</a></p>
42
43 *
44 * <p>Short is two bytes and Long is four bytes in big endian byte and
45 * word order, device numbers are currently not supported.</p>
46 *
47 */
48public class AsiExtraField implements ZipExtraField, UnixStat, Cloneable {
49
50 private static final ZipShort HEADER_ID = new ZipShort(0x756E);
51
52 /**
53 * Standard Unix stat(2) file mode.
54 *
55 * @since 1.1
56 */
57 private int mode = 0;
58 /**
59 * User ID.
60 *
61 * @since 1.1
62 */
63 private int uid = 0;
64 /**
65 * Group ID.
66 *
67 * @since 1.1
68 */
69 private int gid = 0;
70 /**
71 * File this entry points to, if it is a symbolic link.
72 *
73 * <p>empty string - if entry is not a symbolic link.</p>
74 *
75 * @since 1.1
76 */
77 private String link = "";
78 /**
79 * Is this an entry for a directory?
80 *
81 * @since 1.1
82 */
83 private boolean dirFlag = false;
84
85 /**
86 * Instance used to calculate checksums.
87 *
88 * @since 1.1
89 */
90 private CRC32 crc = new CRC32();
91
92 public AsiExtraField() {
93 }
94
95 /**
96 * The Header-ID.
97 *
98 * @since 1.1
99 */
100 public ZipShort getHeaderId() {
101 return HEADER_ID;
102 }
103
104 /**
105 * Length of the extra field in the local file data - without
106 * Header-ID or length specifier.
107 *
108 * @since 1.1
109 */
110 public ZipShort getLocalFileDataLength() {
111 return new ZipShort(4 // CRC
112 + 2 // Mode
113 + 4 // SizDev
114 + 2 // UID
115 + 2 // GID
116 + getLinkedFile().getBytes().length);
117 }
118
119 /**
120 * Delegate to local file data.
121 *
122 * @since 1.1
123 */
124 public ZipShort getCentralDirectoryLength() {
125 return getLocalFileDataLength();
126 }
127
128 /**
129 * The actual data to put into local file data - without Header-ID
130 * or length specifier.
131 *
132 * @since 1.1
133 */
134 public byte[] getLocalFileDataData() {
135 // CRC will be added later
136 byte[] data = new byte[getLocalFileDataLength().getValue() - 4];
137 System.arraycopy((new ZipShort(getMode())).getBytes(), 0, data, 0, 2);
138
139 byte[] linkArray = getLinkedFile().getBytes();
140 System.arraycopy((new ZipLong(linkArray.length)).getBytes(),
141 0, data, 2, 4);
142
143 System.arraycopy((new ZipShort(getUserId())).getBytes(),
144 0, data, 6, 2);
145 System.arraycopy((new ZipShort(getGroupId())).getBytes(),
146 0, data, 8, 2);
147
148 System.arraycopy(linkArray, 0, data, 10, linkArray.length);
149
150 crc.reset();
151 crc.update(data);
152 long checksum = crc.getValue();
153
154 byte[] result = new byte[data.length + 4];
155 System.arraycopy((new ZipLong(checksum)).getBytes(), 0, result, 0, 4);
156 System.arraycopy(data, 0, result, 4, data.length);
157 return result;
158 }
159
160 /**
161 * Delegate to local file data.
162 *
163 * @since 1.1
164 */
165 public byte[] getCentralDirectoryData() {
166 return getLocalFileDataData();
167 }
168
169 /**
170 * Set the user id.
171 *
172 * @since 1.1
173 */
174 public void setUserId(int uid) {
175 this.uid = uid;
176 }
177
178 /**
179 * Get the user id.
180 *
181 * @since 1.1
182 */
183 public int getUserId() {
184 return uid;
185 }
186
187 /**
188 * Set the group id.
189 *
190 * @since 1.1
191 */
192 public void setGroupId(int gid) {
193 this.gid = gid;
194 }
195
196 /**
197 * Get the group id.
198 *
199 * @since 1.1
200 */
201 public int getGroupId() {
202 return gid;
203 }
204
205 /**
206 * Indicate that this entry is a symbolic link to the given filename.
207 *
208 * @param name Name of the file this entry links to, empty String
209 * if it is not a symbolic link.
210 *
211 * @since 1.1
212 */
213 public void setLinkedFile(String name) {
214 link = name;
215 mode = getMode(mode);
216 }
217
218 /**
219 * Name of linked file
220 *
221 * @return name of the file this entry links to if it is a
222 * symbolic link, the empty string otherwise.
223 *
224 * @since 1.1
225 */
226 public String getLinkedFile() {
227 return link;
228 }
229
230 /**
231 * Is this entry a symbolic link?
232 *
233 * @since 1.1
234 */
235 public boolean isLink() {
236 return getLinkedFile().length() != 0;
237 }
238
239 /**
240 * File mode of this file.
241 *
242 * @since 1.1
243 */
244 public void setMode(int mode) {
245 this.mode = getMode(mode);
246 }
247
248 /**
249 * File mode of this file.
250 *
251 * @since 1.1
252 */
253 public int getMode() {
254 return mode;
255 }
256
257 /**
258 * Indicate whether this entry is a directory.
259 *
260 * @since 1.1
261 */
262 public void setDirectory(boolean dirFlag) {
263 this.dirFlag = dirFlag;
264 mode = getMode(mode);
265 }
266
267 /**
268 * Is this entry a directory?
269 *
270 * @since 1.1
271 */
272 public boolean isDirectory() {
273 return dirFlag && !isLink();
274 }
275
276 /**
277 * Populate data from this array as if it was in local file data.
278 *
279 * @since 1.1
280 */
281 public void parseFromLocalFileData(byte[] data, int offset, int length)
282 throws ZipException {
283
284 long givenChecksum = (new ZipLong(data, offset)).getValue();
285 byte[] tmp = new byte[length - 4];
286 System.arraycopy(data, offset + 4, tmp, 0, length - 4);
287 crc.reset();
288 crc.update(tmp);
289 long realChecksum = crc.getValue();
290 if (givenChecksum != realChecksum) {
291 throw new ZipException("bad CRC checksum "
292 + Long.toHexString(givenChecksum)
293 + " instead of "
294 + Long.toHexString(realChecksum));
295 }
296
297 int newMode = (new ZipShort(tmp, 0)).getValue();
298 byte[] linkArray = new byte[(int) (new ZipLong(tmp, 2)).getValue()];
299 uid = (new ZipShort(tmp, 6)).getValue();
300 gid = (new ZipShort(tmp, 8)).getValue();
301
302 if (linkArray.length == 0) {
303 link = "";
304 } else {
305 System.arraycopy(tmp, 10, linkArray, 0, linkArray.length);
306 link = new String(linkArray);
307 }
308 setDirectory((newMode & DIR_FLAG) != 0);
309 setMode(newMode);
310 }
311
312 /**
313 * Get the file mode for given permissions with the correct file type.
314 *
315 * @since 1.1
316 */
317 protected int getMode(int mode) {
318 int type = FILE_FLAG;
319 if (isLink()) {
320 type = LINK_FLAG;
321 } else if (isDirectory()) {
322 type = DIR_FLAG;
323 }
324 return type | (mode & PERM_MASK);
325 }
326
327}
Note: See TracBrowser for help on using the repository browser.