- /*
- * Copyright 2001-2002,2004 The Apache Software Foundation
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- *
- */
-
- package org.apache.tools.zip;
-
- import java.util.zip.CRC32;
- import java.util.zip.ZipException;
-
- /**
- * Adds Unix file permission and UID/GID fields as well as symbolic
- * link handling.
- *
- * <p>This class uses the ASi extra field in the format:
- * <pre>
- * Value Size Description
- * ----- ---- -----------
- * (Unix3) 0x756e Short tag for this extra block type
- * TSize Short total data size for this block
- * CRC Long CRC-32 of the remaining data
- * Mode Short file permissions
- * SizDev Long symlink'd size OR major/minor dev num
- * UID Short user ID
- * GID Short group ID
- * (var.) variable symbolic link filename
- * </pre>
- * taken from appnote.iz (Info-ZIP note, 981119) found at <a
- * href="ftp://ftp.uu.net/pub/archiving/zip/doc/">ftp://ftp.uu.net/pub/archiving/zip/doc/</a></p>
-
- *
- * <p>Short is two bytes and Long is four bytes in big endian byte and
- * word order, device numbers are currently not supported.</p>
- *
- * @version $Revision: 1.6.2.4 $
- */
- public class AsiExtraField implements ZipExtraField, UnixStat, Cloneable {
-
- private static final ZipShort HEADER_ID = new ZipShort(0x756E);
-
- /**
- * Standard Unix stat(2) file mode.
- *
- * @since 1.1
- */
- private int mode = 0;
- /**
- * User ID.
- *
- * @since 1.1
- */
- private int uid = 0;
- /**
- * Group ID.
- *
- * @since 1.1
- */
- private int gid = 0;
- /**
- * File this entry points to, if it is a symbolic link.
- *
- * <p>empty string - if entry is not a symbolic link.</p>
- *
- * @since 1.1
- */
- private String link = "";
- /**
- * Is this an entry for a directory?
- *
- * @since 1.1
- */
- private boolean dirFlag = false;
-
- /**
- * Instance used to calculate checksums.
- *
- * @since 1.1
- */
- private CRC32 crc = new CRC32();
-
- public AsiExtraField() {
- }
-
- /**
- * The Header-ID.
- *
- * @since 1.1
- */
- public ZipShort getHeaderId() {
- return HEADER_ID;
- }
-
- /**
- * Length of the extra field in the local file data - without
- * Header-ID or length specifier.
- *
- * @since 1.1
- */
- public ZipShort getLocalFileDataLength() {
- return new ZipShort(4 // CRC
- + 2 // Mode
- + 4 // SizDev
- + 2 // UID
- + 2 // GID
- + getLinkedFile().getBytes().length);
- }
-
- /**
- * Delegate to local file data.
- *
- * @since 1.1
- */
- public ZipShort getCentralDirectoryLength() {
- return getLocalFileDataLength();
- }
-
- /**
- * The actual data to put into local file data - without Header-ID
- * or length specifier.
- *
- * @since 1.1
- */
- public byte[] getLocalFileDataData() {
- // CRC will be added later
- byte[] data = new byte[getLocalFileDataLength().getValue() - 4];
- System.arraycopy((new ZipShort(getMode())).getBytes(), 0, data, 0, 2);
-
- byte[] linkArray = getLinkedFile().getBytes();
- System.arraycopy((new ZipLong(linkArray.length)).getBytes(),
- 0, data, 2, 4);
-
- System.arraycopy((new ZipShort(getUserId())).getBytes(),
- 0, data, 6, 2);
- System.arraycopy((new ZipShort(getGroupId())).getBytes(),
- 0, data, 8, 2);
-
- System.arraycopy(linkArray, 0, data, 10, linkArray.length);
-
- crc.reset();
- crc.update(data);
- long checksum = crc.getValue();
-
- byte[] result = new byte[data.length + 4];
- System.arraycopy((new ZipLong(checksum)).getBytes(), 0, result, 0, 4);
- System.arraycopy(data, 0, result, 4, data.length);
- return result;
- }
-
- /**
- * Delegate to local file data.
- *
- * @since 1.1
- */
- public byte[] getCentralDirectoryData() {
- return getLocalFileDataData();
- }
-
- /**
- * Set the user id.
- *
- * @since 1.1
- */
- public void setUserId(int uid) {
- this.uid = uid;
- }
-
- /**
- * Get the user id.
- *
- * @since 1.1
- */
- public int getUserId() {
- return uid;
- }
-
- /**
- * Set the group id.
- *
- * @since 1.1
- */
- public void setGroupId(int gid) {
- this.gid = gid;
- }
-
- /**
- * Get the group id.
- *
- * @since 1.1
- */
- public int getGroupId() {
- return gid;
- }
-
- /**
- * Indicate that this entry is a symbolic link to the given filename.
- *
- * @param name Name of the file this entry links to, empty String
- * if it is not a symbolic link.
- *
- * @since 1.1
- */
- public void setLinkedFile(String name) {
- link = name;
- mode = getMode(mode);
- }
-
- /**
- * Name of linked file
- *
- * @return name of the file this entry links to if it is a
- * symbolic link, the empty string otherwise.
- *
- * @since 1.1
- */
- public String getLinkedFile() {
- return link;
- }
-
- /**
- * Is this entry a symbolic link?
- *
- * @since 1.1
- */
- public boolean isLink() {
- return getLinkedFile().length() != 0;
- }
-
- /**
- * File mode of this file.
- *
- * @since 1.1
- */
- public void setMode(int mode) {
- this.mode = getMode(mode);
- }
-
- /**
- * File mode of this file.
- *
- * @since 1.1
- */
- public int getMode() {
- return mode;
- }
-
- /**
- * Indicate whether this entry is a directory.
- *
- * @since 1.1
- */
- public void setDirectory(boolean dirFlag) {
- this.dirFlag = dirFlag;
- mode = getMode(mode);
- }
-
- /**
- * Is this entry a directory?
- *
- * @since 1.1
- */
- public boolean isDirectory() {
- return dirFlag && !isLink();
- }
-
- /**
- * Populate data from this array as if it was in local file data.
- *
- * @since 1.1
- */
- public void parseFromLocalFileData(byte[] data, int offset, int length)
- throws ZipException {
-
- long givenChecksum = (new ZipLong(data, offset)).getValue();
- byte[] tmp = new byte[length - 4];
- System.arraycopy(data, offset + 4, tmp, 0, length - 4);
- crc.reset();
- crc.update(tmp);
- long realChecksum = crc.getValue();
- if (givenChecksum != realChecksum) {
- throw new ZipException("bad CRC checksum "
- + Long.toHexString(givenChecksum)
- + " instead of "
- + Long.toHexString(realChecksum));
- }
-
- int newMode = (new ZipShort(tmp, 0)).getValue();
- byte[] linkArray = new byte[(int) (new ZipLong(tmp, 2)).getValue()];
- uid = (new ZipShort(tmp, 6)).getValue();
- gid = (new ZipShort(tmp, 8)).getValue();
-
- if (linkArray.length == 0) {
- link = "";
- } else {
- System.arraycopy(tmp, 10, linkArray, 0, linkArray.length);
- link = new String(linkArray);
- }
- setDirectory((newMode & DIR_FLAG) != 0);
- setMode(newMode);
- }
-
- /**
- * Get the file mode for given permissions with the correct file type.
- *
- * @since 1.1
- */
- protected int getMode(int mode) {
- int type = FILE_FLAG;
- if (isLink()) {
- type = LINK_FLAG;
- } else if (isDirectory()) {
- type = DIR_FLAG;
- }
- return type | (mode & PERM_MASK);
- }
-
- }