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
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
|
/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*/
#ifndef ORCUS_CSV_PARSER_HPP
#define ORCUS_CSV_PARSER_HPP
#include "csv_parser_base.hpp"
namespace orcus {
class csv_handler
{
public:
/**
* Called when the parser starts parsing a stream.
*/
void begin_parse() {}
/**
* Called when the parser finishes parsing a stream.
*/
void end_parse() {}
/**
* Called at the beginning of every row.
*/
void begin_row() {}
/**
* Called at the end of every row.
*/
void end_row() {}
/**
* Called after every cell is parsed.
*
* @param value cell content.
* @param transient when true, the text content has been converted and is
* stored in a temporary buffer. In such case, there is
* no guarantee that the text content remain available
* after the end of the call. When this value is false,
* the text content is guaranteed to be valid so long as
* the original CSV stream content is valid.
*/
void cell(std::string_view value, bool transient)
{
(void)value; (void)transient;
}
};
/**
* Parser for CSV documents.
*
* @tparam HandlerT Hanlder type with member functions for event callbacks.
* Refer to csv_handler.
*/
template<typename HandlerT>
class csv_parser : public csv::parser_base
{
public:
typedef HandlerT handler_type;
csv_parser(std::string_view content, handler_type& hdl, const csv::parser_config& config);
void parse();
private:
// handlers
void row();
void cell();
void quoted_cell();
void parse_cell_with_quote(const char* p0, size_t len0);
/**
* Push cell value to the handler.
*/
void push_cell_value(const char* p, size_t n);
private:
handler_type& m_handler;
};
template<typename _Handler>
csv_parser<_Handler>::csv_parser(
std::string_view content, handler_type& hdl, const csv::parser_config& config) :
csv::parser_base(content, config), m_handler(hdl) {}
template<typename _Handler>
void csv_parser<_Handler>::parse()
{
#if ORCUS_DEBUG_CSV
for (const char* p = mp_begin; p < mp_end; ++p)
std::cout << *p;
std::cout << std::endl;
#endif
m_handler.begin_parse();
while (has_char())
row();
m_handler.end_parse();
}
template<typename _Handler>
void csv_parser<_Handler>::row()
{
m_handler.begin_row();
while (true)
{
if (is_text_qualifier(cur_char()))
quoted_cell();
else
cell();
if (!has_char())
{
m_handler.end_row();
return;
}
char c = cur_char();
if (c == '\n')
{
next();
#if ORCUS_DEBUG_CSV
cout << "(LF)" << endl;
#endif
m_handler.end_row();
return;
}
if (!is_delim(c))
throw orcus::parse_error("expected a delimiter", offset());
next();
if (m_config.trim_cell_value)
skip_blanks();
if (!has_char())
{
m_handler.end_row();
return;
}
}
}
template<typename _Handler>
void csv_parser<_Handler>::cell()
{
const char* p = mp_char;
size_t len = 0;
char c = cur_char();
while (c != '\n' && !is_delim(c))
{
++len;
next();
if (!has_char())
break;
c = cur_char();
}
if (!len)
p = nullptr;
push_cell_value(p, len);
}
template<typename _Handler>
void csv_parser<_Handler>::quoted_cell()
{
#if ORCUS_DEBUG_CSV
cout << "--- quoted cell" << endl;
#endif
char c = cur_char();
assert(is_text_qualifier(c));
next(); // Skip the opening quote.
if (!has_char())
return;
const char* p0 = mp_char;
size_t len = 1;
for (; has_char(); next(), ++len)
{
c = cur_char();
#if ORCUS_DEBUG_CSV
cout << "'" << c << "'" << endl;
#endif
if (!is_text_qualifier(c))
continue;
// current char is a quote. Check if the next char is also a text
// qualifier.
if (has_next() && is_text_qualifier(peek_char()))
{
next();
parse_cell_with_quote(p0, len);
return;
}
// Closing quote.
m_handler.cell({p0, len-1}, false);
next();
skip_blanks();
return;
}
// Stream ended prematurely. Handle it gracefully.
m_handler.cell({p0, len}, false);
}
template<typename _Handler>
void csv_parser<_Handler>::parse_cell_with_quote(const char* p0, size_t len0)
{
#if ORCUS_DEBUG_CSV
using namespace std;
cout << "--- parse cell with quote" << endl;
#endif
assert(is_text_qualifier(cur_char()));
// Push the preceding chars to the temp buffer.
m_cell_buf.reset();
m_cell_buf.append(p0, len0);
// Parse the rest, until the closing quote.
next();
const char* p_cur = mp_char;
size_t cur_len = 0;
for (; has_char(); next(), ++cur_len)
{
char c = cur_char();
#if ORCUS_DEBUG_CSV
cout << "'" << c << "'" << endl;
#endif
if (!is_text_qualifier(c))
continue;
if (has_next() && is_text_qualifier(peek_char()))
{
// double quotation. Copy the current segment to the cell buffer.
m_cell_buf.append(p_cur, cur_len);
next(); // to the 2nd quote.
p_cur = mp_char;
cur_len = 0;
continue;
}
// closing quote. Flush the current segment to the cell
// buffer, push the value to the handler, and exit normally.
m_cell_buf.append(p_cur, cur_len);
m_handler.cell(m_cell_buf.str(), true);
next();
skip_blanks();
return;
}
// Stream ended prematurely.
throw parse_error("stream ended prematurely while parsing quoted cell.", offset());
}
template<typename _Handler>
void csv_parser<_Handler>::push_cell_value(const char* p, size_t n)
{
size_t len = n;
if (m_config.trim_cell_value)
{
// Trim any leading blanks.
for (size_t i = 0; i < n; ++i, --len, ++p)
{
if (!is_blank(*p))
break;
}
// Trim any trailing blanks.
if (len)
{
const char* p_end = p + (len-1);
for (; p != p_end; --p_end, --len)
{
if (!is_blank(*p_end))
break;
}
}
}
m_handler.cell({p, len}, false);
#if ORCUS_DEBUG_CSV
if (len)
cout << "(cell:'" << std::string(p, len) << "')" << endl;
else
cout << "(cell:'')" << endl;
#endif
}
}
#endif
/* vim:set shiftwidth=4 softtabstop=4 expandtab: */
|