1#region Copyright notice and license
2// Protocol Buffers - Google's data interchange format
3// Copyright 2008 Google Inc.  All rights reserved.
4// https://developers.google.com/protocol-buffers/
5//
6// Redistribution and use in source and binary forms, with or without
7// modification, are permitted provided that the following conditions are
8// met:
9//
10//     * Redistributions of source code must retain the above copyright
11// notice, this list of conditions and the following disclaimer.
12//     * Redistributions in binary form must reproduce the above
13// copyright notice, this list of conditions and the following disclaimer
14// in the documentation and/or other materials provided with the
15// distribution.
16//     * Neither the name of Google Inc. nor the names of its
17// contributors may be used to endorse or promote products derived from
18// this software without specific prior written permission.
19//
20// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
21// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
22// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
23// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
24// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
25// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
26// 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
30// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
31#endregion
32
33using System;
34using System.Buffers;
35using System.Buffers.Binary;
36using System.Collections.Generic;
37using System.IO;
38using System.Runtime.CompilerServices;
39using System.Runtime.InteropServices;
40using System.Security;
41using System.Text;
42using Google.Protobuf.Collections;
43
44namespace Google.Protobuf
45{
46
47    // warning: this is a mutable struct, so it needs to be only passed as a ref!
48    internal struct ParserInternalState
49    {
50        // NOTE: the Span representing the current buffer is kept separate so that this doesn't have to be a ref struct and so it can
51        // be included in CodedInputStream's internal state
52
53        /// <summary>
54        /// The position within the current buffer (i.e. the next byte to read)
55        /// </summary>
56        internal int bufferPos;
57
58        /// <summary>
59        /// Size of the current buffer
60        /// </summary>
61        internal int bufferSize;
62
63        /// <summary>
64        /// If we are currently inside a length-delimited block, this is the number of
65        /// bytes in the buffer that are still available once we leave the delimited block.
66        /// </summary>
67        internal int bufferSizeAfterLimit;
68
69        /// <summary>
70        /// The absolute position of the end of the current length-delimited block (including totalBytesRetired)
71        /// </summary>
72        internal int currentLimit;
73
74        /// <summary>
75        /// The total number of consumed before the start of the current buffer. The
76        /// total bytes read up to the current position can be computed as
77        /// totalBytesRetired + bufferPos.
78        /// </summary>
79        internal int totalBytesRetired;
80
81        internal int recursionDepth;  // current recursion depth
82
83        internal SegmentedBufferHelper segmentedBufferHelper;
84
85        /// <summary>
86        /// The last tag we read. 0 indicates we've read to the end of the stream
87        /// (or haven't read anything yet).
88        /// </summary>
89        internal uint lastTag;
90
91        /// <summary>
92        /// The next tag, used to store the value read by PeekTag.
93        /// </summary>
94        internal uint nextTag;
95        internal bool hasNextTag;
96
97        // these fields are configuration, they should be readonly
98        internal int sizeLimit;
99        internal int recursionLimit;
100
101        // If non-null, the top level parse method was started with given coded input stream as an argument
102        // which also means we can potentially fallback to calling MergeFrom(CodedInputStream cis) if needed.
103        internal CodedInputStream CodedInputStream => segmentedBufferHelper.CodedInputStream;
104
105        /// <summary>
106        /// Internal-only property; when set to true, unknown fields will be discarded while parsing.
107        /// </summary>
108        internal bool DiscardUnknownFields { get; set; }
109
110        /// <summary>
111        /// Internal-only property; provides extension identifiers to compatible messages while parsing.
112        /// </summary>
113        internal ExtensionRegistry ExtensionRegistry { get; set; }
114    }
115}