1 /* -*-mode:java; c-basic-offset:2; -*- */
2 /*
3 Copyright (c) 2011 ymnk, JCraft,Inc. All rights reserved.
4 
5 Redistribution and use in source and binary forms, with or without
6 modification, are permitted provided that the following conditions are met:
7 
8   1. Redistributions of source code must retain the above copyright notice,
9      this list of conditions and the following disclaimer.
10 
11   2. Redistributions in binary form must reproduce the above copyright
12      notice, this list of conditions and the following disclaimer in
13      the documentation and/or other materials provided with the distribution.
14 
15   3. The names of the authors may not be used to endorse or promote products
16      derived from this software without specific prior written permission.
17 
18 THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES,
19 INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
20 FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL JCRAFT,
21 INC. OR ANY CONTRIBUTORS TO THIS SOFTWARE BE LIABLE FOR ANY DIRECT, INDIRECT,
22 INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
23 LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
24 OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
25 LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
26 NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
27 EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28  */
29 /*
30  * This program is based on zlib-1.1.3, so all credit should go authors
31  * Jean-loup Gailly(jloup@gzip.org) and Mark Adler(madler@alumni.caltech.edu)
32  * and contributors of zlib.
33  */
34 
35 package com.jcraft.jzlib;
36 
37 import java.io.UnsupportedEncodingException;
38 
39 /**
40  * @see "http://www.ietf.org/rfc/rfc1952.txt"
41  */
42 public class GZIPHeader implements Cloneable {
43 
44   public static final byte OS_MSDOS = (byte) 0x00;
45   public static final byte OS_AMIGA = (byte) 0x01;
46   public static final byte OS_VMS = (byte) 0x02;
47   public static final byte OS_UNIX = (byte) 0x03;
48   public static final byte OS_ATARI = (byte) 0x05;
49   public static final byte OS_OS2 = (byte) 0x06;
50   public static final byte OS_MACOS = (byte) 0x07;
51   public static final byte OS_TOPS20 = (byte) 0x0a;
52   public static final byte OS_WIN32 = (byte) 0x0b;
53   public static final byte OS_VMCMS = (byte) 0x04;
54   public static final byte OS_ZSYSTEM = (byte) 0x08;
55   public static final byte OS_CPM = (byte) 0x09;
56   public static final byte OS_QDOS = (byte) 0x0c;
57   public static final byte OS_RISCOS = (byte) 0x0d;
58   public static final byte OS_UNKNOWN = (byte) 0xff;
59 
60   boolean text = false;
61   private boolean fhcrc = false;
62   long time;
63   int xflags;
64   int os = 255;
65   byte[] extra;
66   byte[] name;
67   byte[] comment;
68   int hcrc;
69   long crc;
70   boolean done = false;
71   long mtime = 0;
72 
setModifiedTime(long mtime)73   public void setModifiedTime(long mtime) {
74     this.mtime = mtime;
75   }
76 
getModifiedTime()77   public long getModifiedTime() {
78     return mtime;
79   }
80 
setOS(int os)81   public void setOS(int os) {
82     if((0<=os && os <=13) || os==255)
83       this.os=os;
84     else
85       throw new IllegalArgumentException("os: "+os);
86   }
87 
getOS()88   public int getOS(){
89     return os;
90   }
91 
setName(String name)92   public void setName(String name) {
93     try{
94       this.name=name.getBytes("ISO-8859-1");
95     }
96     catch(UnsupportedEncodingException e){
97       throw new IllegalArgumentException("name must be in ISO-8859-1 "+name);
98     }
99   }
100 
getName()101   public String getName(){
102     if(name==null) return "";
103     try {
104       return new String(name, "ISO-8859-1");
105     }
106     catch (UnsupportedEncodingException e) {
107       throw new InternalError(e.toString());
108     }
109   }
110 
setComment(String comment)111   public void setComment(String comment) {
112     try{
113       this.comment=comment.getBytes("ISO-8859-1");
114     }
115     catch(UnsupportedEncodingException e){
116       throw new IllegalArgumentException("comment must be in ISO-8859-1 "+name);
117     }
118   }
119 
getComment()120   public String getComment(){
121     if(comment==null) return "";
122     try {
123       return new String(comment, "ISO-8859-1");
124     }
125     catch (UnsupportedEncodingException e) {
126       throw new InternalError(e.toString());
127     }
128   }
129 
setCRC(long crc)130   public void setCRC(long crc){
131     this.crc = crc;
132   }
133 
getCRC()134   public long getCRC(){
135     return crc;
136   }
137 
put(Deflate d)138   void put(Deflate d){
139     int flag = 0;
140     if(text){
141       flag |= 1;     // FTEXT
142     }
143     if(fhcrc){
144       flag |= 2;     // FHCRC
145     }
146     if(extra!=null){
147       flag |= 4;     // FEXTRA
148     }
149     if(name!=null){
150       flag |= 8;    // FNAME
151     }
152     if(comment!=null){
153       flag |= 16;   // FCOMMENT
154     }
155     int xfl = 0;
156     if(d.level == JZlib.Z_BEST_SPEED){
157       xfl |= 4;
158     }
159     else if (d.level == JZlib.Z_BEST_COMPRESSION){
160       xfl |= 2;
161     }
162 
163     d.put_short((short)0x8b1f);  // ID1 ID2
164     d.put_byte((byte)8);         // CM(Compression Method)
165     d.put_byte((byte)flag);
166     d.put_byte((byte)mtime);
167     d.put_byte((byte)(mtime>>8));
168     d.put_byte((byte)(mtime>>16));
169     d.put_byte((byte)(mtime>>24));
170     d.put_byte((byte)xfl);
171     d.put_byte((byte)os);
172 
173     if(extra!=null){
174       d.put_byte((byte)extra.length);
175       d.put_byte((byte)(extra.length>>8));
176       d.put_byte(extra, 0, extra.length);
177     }
178 
179     if(name!=null){
180       d.put_byte(name, 0, name.length);
181       d.put_byte((byte)0);
182     }
183 
184     if(comment!=null){
185       d.put_byte(comment, 0, comment.length);
186       d.put_byte((byte)0);
187     }
188   }
189 
190   @Override
clone()191   public Object clone() throws CloneNotSupportedException {
192     GZIPHeader gheader = (GZIPHeader)super.clone();
193     byte[] tmp;
194     if(gheader.extra!=null){
195       tmp=new byte[gheader.extra.length];
196       System.arraycopy(gheader.extra, 0, tmp, 0, tmp.length);
197       gheader.extra = tmp;
198     }
199 
200     if(gheader.name!=null){
201       tmp=new byte[gheader.name.length];
202       System.arraycopy(gheader.name, 0, tmp, 0, tmp.length);
203       gheader.name = tmp;
204     }
205 
206     if(gheader.comment!=null){
207       tmp=new byte[gheader.comment.length];
208       System.arraycopy(gheader.comment, 0, tmp, 0, tmp.length);
209       gheader.comment = tmp;
210     }
211 
212     return gheader;
213   }
214 }
215