1/*
2 * [The "BSD licence"]
3 * Copyright (c) 2005-2008 Terence Parr
4 * All rights reserved.
5 *
6 * Conversion to C#:
7 * Copyright (c) 2008-2009 Sam Harwell, Pixel Mine, Inc.
8 * All rights reserved.
9 *
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
12 * are met:
13 * 1. Redistributions of source code must retain the above copyright
14 *    notice, this list of conditions and the following disclaimer.
15 * 2. Redistributions in binary form must reproduce the above copyright
16 *    notice, this list of conditions and the following disclaimer in the
17 *    documentation and/or other materials provided with the distribution.
18 * 3. The name of the author may not be used to endorse or promote products
19 *    derived from this software without specific prior written permission.
20 *
21 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
22 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
23 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
24 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
25 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
26 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
27 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
28 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
29 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
30 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31 */
32
33namespace Antlr.Runtime
34{
35    using TextReader = System.IO.TextReader;
36
37    /** <summary>
38     *  Vacuum all input from a Reader and then treat it like a StringStream.
39     *  Manage the buffer manually to avoid unnecessary data copying.
40     *  </summary>
41     *
42     *  <remarks>
43     *  If you need encoding, use ANTLRInputStream.
44     *  </remarks>
45     */
46    [System.Serializable]
47    public class ANTLRReaderStream : ANTLRStringStream
48    {
49        public const int ReadBufferSize = 1024;
50        public const int InitialBufferSize = 1024;
51
52        public ANTLRReaderStream( TextReader r )
53            : this( r, InitialBufferSize, ReadBufferSize )
54        {
55        }
56
57        public ANTLRReaderStream( TextReader r, int size )
58            : this( r, size, ReadBufferSize )
59        {
60        }
61
62        public ANTLRReaderStream( TextReader r, int size, int readChunkSize )
63        {
64            Load( r, size, readChunkSize );
65        }
66
67        public virtual void Load( TextReader r, int size, int readChunkSize )
68        {
69            if ( r == null )
70            {
71                return;
72            }
73            if ( size <= 0 )
74            {
75                size = InitialBufferSize;
76            }
77            if ( readChunkSize <= 0 )
78            {
79                readChunkSize = ReadBufferSize;
80            }
81            // System.out.println("load "+size+" in chunks of "+readChunkSize);
82            try
83            {
84                data = r.ReadToEnd().ToCharArray();
85                base.n = data.Length;
86            }
87            finally
88            {
89                r.Close();
90            }
91        }
92    }
93}
94