1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
|
/*
Ousía
Copyright (C) 2014 Benjamin Paaßen, Andreas Stöckel
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef _OUSIA_PLAIN_FORMAT_STREAM_READER_HPP_
#define _OUSIA_PLAIN_FORMAT_STREAM_READER_HPP_
/**
* @file PlainFormatStreamReader.hpp
*
* Provides classes for low-level classes for reading the plain TeX-esque
* format. The class provided here do not build any model objects and does not
* implement the Parser interfaces.
*
* @author Andreas Stöckel (astoecke@techfak.uni-bielefeld.de)
*/
#include <core/common/Variant.hpp>
#include "DynamicTokenizer.hpp"
namespace ousia {
// Forward declarations
class CharReader;
class Logger;
/**
* The PlainFormatStreamReader class provides a low-level reader for the plain
* TeX-esque format. The parser is constructed around a "parse" function, which
* reads data from the underlying CharReader until a new state is reached and
* indicates this state in a return value. The calling code then has to pull
* corresponding data from the stream reader. The reader already handles some
* invalid cases, but recovers from most errors and happily continues parsing.
*/
class PlainFormatStreamReader {
public:
/**
* Enum used to indicate which state the PlainFormatStreamReader class is in
* after calling the "parse" function.
*/
enum class State {
/**
* State returned if a fully featured command has been read. A command
* consists of the command name and its arguments (which optionally
* includes the name).
*/
COMMAND,
/**
* State returned if data is given. The reader must decide which field
* or command this should be routed to. Trailing or leading whitespace
* has been removed. Only called if the data is non-empty.
*/
DATA,
/**
* State returned if a linebreak has been reached (outside of comments).
*/
LINEBREAK,
/**
* A user-defined entity has been found. The entity sequence is stored
* in the command name.
*/
ENTITY,
/**
* State returned if an annotation was started. An annotation consists
* of the command name and its arguments (which optionally include the
* name).
*/
ANNOTATION_START,
/**
* State returned if an annotation ends. The reader indicates which
* annotation ends.
*/
ANNOTATION_END,
/**
* State returned if a new field started. The reader assures that the
* current field ends before a new field is started and that the field
* is not started if data has been given outside of a field. The
* field number is set to the current field index.
*/
FIELD_START,
/**
* State returned if the current field ends. The reader assures that a
* field was actually open.
*/
FIELD_END,
/**
* The end of the stream has been reached.
*/
END
};
private:
/**
* Reference to the CharReader instance from which the incomming bytes are
* read.
*/
CharReader &reader;
/**
* Reference at the logger instance to which all error messages are sent.
*/
Logger &logger;
/**
* Tokenizer instance used to read individual tokens from the text.
*/
DynamicTokenizer tokenizer;
/**
* Variant containing the current command name (always is a string variant,
* but additionally contains the correct locatino of the name).
*/
Variant commandName;
/**
* Variant containing the command arguments (always is a map or array
* variant, but additionally contains the source location of the arguments).
*/
Variant commandArguments;
/**
* Variant containing the data that has been read (always is a string,
* contains the exact location of the data in the source file).
*/
Variant data;
/**
* Id of the backslash token.
*/
TokenTypeId tokenBackslash;
/**
* Id of the linebreak token.
*/
TokenTypeId tokenLinebreak;
/**
* Id of the line comment token.
*/
TokenTypeId tokenLineComment;
/**
* Id of the block comment start token.
*/
TokenTypeId tokenBlockCommentStart;
/**
* If of the block comment end token.
*/
TokenTypeId tokenBlockCommentEnd;
/**
* Contains the field index of the current command.
*/
size_t fieldIdx;
/**
* Function used internally to parse a block comment.
*/
void parseBlockComment();
/**
* Function used internally to parse a generic comment.
*/
void parseLineComment();
public:
/**
* Constructor of the PlainFormatStreamReader class. Attaches the new
* PlainFormatStreamReader to the given CharReader and Logger instances.
*
* @param reader is the reader instance from which incomming characters
* should be read.
* @param logger is the logger instance to which errors should be written.
*/
PlainFormatStreamReader(CharReader &reader, Logger &logger);
/**
* Continues parsing. Returns one of the states defined in the State enum.
* Callers should stop once the State::END state is reached. Use the getter
* functions to get more information about the current state, such as the
* command name or the data or the current field index.
*
* @return the new state the parser has reached.
*/
State parse();
/**
* Returns a reference at the internally stored data.
*/
const Variant& getData() {return data;}
};
}
#endif /* _OUSIA_PLAIN_FORMAT_STREAM_READER_HPP_ */
|
