1/*
2 * Copyright (c) 1997, 2013, 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
26package com.sun.xml.internal.org.jvnet.mimepull;
27
28import java.io.InputStream;
29import java.io.IOException;
30
31/**
32 * Constructs a InputStream from a linked list of {@link Chunk}s.
33 *
34 * @author Kohsuke Kawaguchi
35 * @author Jitendra Kotamraju
36 */
37final class ChunkInputStream extends InputStream {
38    Chunk current;
39    int offset;
40    int len;
41    final MIMEMessage msg;
42    final MIMEPart part;
43    byte[] buf;
44
45    public ChunkInputStream(MIMEMessage msg, MIMEPart part, Chunk startPos) {
46        this.current = startPos;
47        len = current.data.size();
48        buf = current.data.read();
49        this.msg = msg;
50        this.part = part;
51    }
52
53    @Override
54    public int read(byte b[], int off, int sz) throws IOException {
55        if (!fetch()) {
56            return -1;
57        }
58
59        sz = Math.min(sz, len-offset);
60        System.arraycopy(buf,offset,b,off,sz);
61        return sz;
62    }
63
64    public int read() throws IOException {
65        if (!fetch()) {
66            return -1;
67        }
68        return (buf[offset++] & 0xff);
69    }
70
71    /**
72     * Gets to the next chunk if we are done with the current one.
73     * @return
74     */
75    private boolean fetch() {
76        if (current == null) {
77            throw new IllegalStateException("Stream already closed");
78        }
79        while(offset==len) {
80            while(!part.parsed && current.next == null) {
81                msg.makeProgress();
82            }
83            current = current.next;
84
85            if (current == null) {
86                return false;
87            }
88            this.offset = 0;
89            this.buf = current.data.read();
90            this.len = current.data.size();
91        }
92        return true;
93    }
94
95    @Override
96    public void close() throws IOException {
97        super.close();
98        current = null;
99    }
100}
101