1 // ========================================================================
2 // Copyright (c) 2002-2009 Mort Bay Consulting Pty. Ltd.
3 // ------------------------------------------------------------------------
4 // All rights reserved. This program and the accompanying materials
5 // are made available under the terms of the Eclipse Public License v1.0
6 // and Apache License v2.0 which accompanies this distribution.
7 // The Eclipse Public License is available at
8 // http://www.eclipse.org/legal/epl-v10.html
9 // The Apache License v2.0 is available at
10 // http://www.opensource.org/licenses/apache2.0.php
11 // You may elect to redistribute this code under either of these licenses.
12 // ========================================================================
13
14 package org.eclipse.jetty.server;
15
16 import java.util.Enumeration;
17 import java.util.List;
18 import java.util.StringTokenizer;
19
20 import org.eclipse.jetty.util.LazyList;
21 import org.eclipse.jetty.util.log.Log;
22
23 /* ------------------------------------------------------------ */
24 /** Byte range inclusive of end points.
25 * <PRE>
26 *
27 * parses the following types of byte ranges:
28 *
29 * bytes=100-499
30 * bytes=-300
31 * bytes=100-
32 * bytes=1-2,2-3,6-,-2
33 *
34 * given an entity length, converts range to string
35 *
36 * bytes 100-499/500
37 *
38 * </PRE>
39 *
40 * Based on RFC2616 3.12, 14.16, 14.35.1, 14.35.2
41 * @version $version$
42 *
43 */
44 public class InclusiveByteRange
45 {
46 long first = 0;
47 long last = 0;
48
49 public InclusiveByteRange(long first, long last)
50 {
51 this.first = first;
52 this.last = last;
53 }
54
55 public long getFirst()
56 {
57 return first;
58 }
59
60 public long getLast()
61 {
62 return last;
63 }
64
65
66
67 /* ------------------------------------------------------------ */
68 /**
69 * @param headers Enumeration of Range header fields.
70 * @param size Size of the resource.
71 * @return LazyList of satisfiable ranges
72 */
73 public static List satisfiableRanges(Enumeration headers,long size)
74 {
75 Object satRanges=null;
76
77 // walk through all Range headers
78 headers:
79 while (headers.hasMoreElements())
80 {
81 String header = (String) headers.nextElement();
82 StringTokenizer tok = new StringTokenizer(header,"=,",false);
83 String t=null;
84 try
85 {
86 // read all byte ranges for this header
87 while (tok.hasMoreTokens())
88 {
89 t=tok.nextToken().trim();
90
91 long first = -1;
92 long last = -1;
93 int d=t.indexOf('-');
94 if (d<0 || t.indexOf("-",d+1)>=0)
95 {
96 if ("bytes".equals(t))
97 continue;
98 Log.warn("Bad range format: {}",t);
99 continue headers;
100 }
101 else if (d==0)
102 {
103 if (d+1<t.length())
104 last = Long.parseLong(t.substring(d+1).trim());
105 else
106 {
107 Log.warn("Bad range format: {}",t);
108 continue headers;
109 }
110 }
111 else if (d+1<t.length())
112 {
113 first = Long.parseLong(t.substring(0,d).trim());
114 last = Long.parseLong(t.substring(d+1).trim());
115 }
116 else
117 first = Long.parseLong(t.substring(0,d).trim());
118
119
120 if (first == -1 && last == -1)
121 continue headers;
122
123 if (first != -1 && last != -1 && (first > last))
124 continue headers;
125
126 if (first<size)
127 {
128 InclusiveByteRange range = new
129 InclusiveByteRange(first, last);
130 satRanges=LazyList.add(satRanges,range);
131 }
132 }
133 }
134 catch(Exception e)
135 {
136 Log.warn("Bad range format: "+t);
137 Log.ignore(e);
138 }
139 }
140 return LazyList.getList(satRanges,true);
141 }
142
143 /* ------------------------------------------------------------ */
144 public long getFirst(long size)
145 {
146 if (first<0)
147 {
148 long tf=size-last;
149 if (tf<0)
150 tf=0;
151 return tf;
152 }
153 return first;
154 }
155
156 /* ------------------------------------------------------------ */
157 public long getLast(long size)
158 {
159 if (first<0)
160 return size-1;
161
162 if (last<0 ||last>=size)
163 return size-1;
164 return last;
165 }
166
167 /* ------------------------------------------------------------ */
168 public long getSize(long size)
169 {
170 return getLast(size)-getFirst(size)+1;
171 }
172
173
174 /* ------------------------------------------------------------ */
175 public String toHeaderRangeString(long size)
176 {
177 StringBuilder sb = new StringBuilder(40);
178 sb.append("bytes ");
179 sb.append(getFirst(size));
180 sb.append('-');
181 sb.append(getLast(size));
182 sb.append("/");
183 sb.append(size);
184 return sb.toString();
185 }
186
187 /* ------------------------------------------------------------ */
188 public static String to416HeaderRangeString(long size)
189 {
190 StringBuilder sb = new StringBuilder(40);
191 sb.append("bytes */");
192 sb.append(size);
193 return sb.toString();
194 }
195
196
197 /* ------------------------------------------------------------ */
198 public String toString()
199 {
200 StringBuilder sb = new StringBuilder(60);
201 sb.append(Long.toString(first));
202 sb.append(":");
203 sb.append(Long.toString(last));
204 return sb.toString();
205 }
206
207
208 }
209
210
211