-
Notifications
You must be signed in to change notification settings - Fork 14
Expand file tree
/
Copy pathroute_abnf.cpp
More file actions
610 lines (503 loc) · 13.2 KB
/
route_abnf.cpp
File metadata and controls
610 lines (503 loc) · 13.2 KB
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
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
//
// Copyright (c) 2025 Vinnie Falco (vinnie.falco@gmail.com)
//
// Distributed under the Boost Software License, Version 1.0. (See accompanying
// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
//
// Official repository: https://github.com/cppalliance/http
//
#include "src/server/route_abnf.hpp"
#include <boost/url/grammar/error.hpp>
namespace boost {
namespace http {
namespace detail {
namespace {
//------------------------------------------------
// Character classification
//------------------------------------------------
// Special characters that have meaning in patterns
constexpr bool
is_special(char c) noexcept
{
switch(c)
{
case '{':
case '}':
case '(':
case ')':
case '[':
case ']':
case '+':
case '?':
case '!':
case ':':
case '*':
case '\\':
return true;
default:
return false;
}
}
// Reserved characters (parsed but invalid)
constexpr bool
is_reserved(char c) noexcept
{
switch(c)
{
case '(':
case ')':
case '[':
case ']':
case '+':
case '?':
case '!':
return true;
default:
return false;
}
}
// Valid identifier start (ASCII subset of ID_Start)
constexpr bool
is_id_start(char c) noexcept
{
return
(c >= 'a' && c <= 'z') ||
(c >= 'A' && c <= 'Z') ||
c == '_' || c == '$';
}
// Valid identifier continuation (ASCII subset of ID_Continue)
constexpr bool
is_id_continue(char c) noexcept
{
return
is_id_start(c) ||
(c >= '0' && c <= '9');
}
//------------------------------------------------
// Parser state
//------------------------------------------------
class parser
{
char const* it_;
char const* end_;
core::string_view original_;
public:
parser(core::string_view s)
: it_(s.data())
, end_(s.data() + s.size())
, original_(s)
{
}
bool
at_end() const noexcept
{
return it_ == end_;
}
char
peek() const noexcept
{
return *it_;
}
void
advance() noexcept
{
++it_;
}
char
get() noexcept
{
return *it_++;
}
std::size_t
pos() const noexcept
{
return static_cast<std::size_t>(
it_ - original_.data());
}
//--------------------------------------------
// Name parsing
//--------------------------------------------
// Parse identifier: id-start *id-continue
system::result<std::string>
parse_identifier()
{
if(at_end() || !is_id_start(peek()))
return grammar::error::mismatch;
std::string result;
result += get();
while(!at_end() && is_id_continue(peek()))
result += get();
return result;
}
// Parse quoted name: DQUOTE *quoted-char DQUOTE
system::result<std::string>
parse_quoted_name()
{
if(at_end() || peek() != '"')
return grammar::error::mismatch;
advance(); // skip opening quote
std::string result;
while(!at_end())
{
char c = peek();
if(c == '"')
{
advance(); // skip closing quote
if(result.empty())
return grammar::error::syntax;
return result;
}
if(c == '\\')
{
advance(); // skip backslash
if(at_end())
return grammar::error::syntax;
result += get();
}
else
{
result += get();
}
}
// Unterminated quote
return grammar::error::syntax;
}
// Parse name: identifier / quoted-name
system::result<std::string>
parse_name()
{
if(at_end())
return grammar::error::syntax;
if(peek() == '"')
return parse_quoted_name();
return parse_identifier();
}
//--------------------------------------------
// Token parsing
//--------------------------------------------
// Parse text: 1*(char / escaped-char)
system::result<route_token>
parse_text()
{
std::string result;
while(!at_end())
{
char c = peek();
// Stop at special characters
if(is_special(c))
{
if(c == '\\')
{
// Escaped character
advance();
if(at_end())
return grammar::error::syntax;
result += get();
continue;
}
break;
}
result += get();
}
if(result.empty())
return grammar::error::mismatch;
return route_token(route_token_type::text, std::move(result));
}
// Parse param: ":" name
system::result<route_token>
parse_param()
{
if(at_end() || peek() != ':')
return grammar::error::mismatch;
advance(); // skip ':'
auto rv = parse_name();
if(rv.has_error())
return rv.error();
return route_token(
route_token_type::param, std::move(rv.value()));
}
// Parse wildcard: "*" name
system::result<route_token>
parse_wildcard()
{
if(at_end() || peek() != '*')
return grammar::error::mismatch;
advance(); // skip '*'
auto rv = parse_name();
if(rv.has_error())
return rv.error();
return route_token(
route_token_type::wildcard, std::move(rv.value()));
}
// Parse group: "{" *token "}"
system::result<route_token>
parse_group()
{
if(at_end() || peek() != '{')
return grammar::error::mismatch;
advance(); // skip '{'
route_token group;
group.type = route_token_type::group;
// Parse tokens until '}'
while(!at_end() && peek() != '}')
{
auto rv = parse_token();
if(rv.has_error())
return rv.error();
group.children.push_back(std::move(rv.value()));
}
if(at_end())
return grammar::error::syntax; // unclosed group
advance(); // skip '}'
return group;
}
// Parse single token
system::result<route_token>
parse_token()
{
if(at_end())
return grammar::error::syntax;
char c = peek();
// Check for reserved characters
if(is_reserved(c))
return grammar::error::syntax;
// Try each token type
if(c == ':')
return parse_param();
if(c == '*')
return parse_wildcard();
if(c == '{')
return parse_group();
if(c == '}')
return grammar::error::syntax; // unexpected '}'
// Must be text
return parse_text();
}
// Parse entire pattern
system::result<std::vector<route_token>>
parse_tokens()
{
std::vector<route_token> tokens;
while(!at_end())
{
auto rv = parse_token();
if(rv.has_error())
return rv.error();
tokens.push_back(std::move(rv.value()));
}
return tokens;
}
};
//------------------------------------------------
// Case-insensitive comparison
//------------------------------------------------
bool
ci_equal(char a, char b) noexcept
{
if(a >= 'A' && a <= 'Z')
a = static_cast<char>(a + 32);
if(b >= 'A' && b <= 'Z')
b = static_cast<char>(b + 32);
return a == b;
}
bool
ci_starts_with(
core::string_view str,
core::string_view prefix) noexcept
{
if(prefix.size() > str.size())
return false;
for(std::size_t i = 0; i < prefix.size(); ++i)
{
if(!ci_equal(str[i], prefix[i]))
return false;
}
return true;
}
//------------------------------------------------
// Route matcher
//------------------------------------------------
class route_matcher
{
core::string_view path_;
match_options const& opts_;
std::vector<std::pair<std::string, std::string>> params_;
std::size_t pos_ = 0;
public:
route_matcher(
core::string_view path,
match_options const& opts)
: path_(path)
, opts_(opts)
{
}
bool at_end() const noexcept
{
return pos_ >= path_.size();
}
std::size_t pos() const noexcept
{
return pos_;
}
std::vector<std::pair<std::string, std::string>> const&
params() const noexcept
{
return params_;
}
// Match text token
bool match_text(core::string_view text)
{
auto remaining = path_.substr(pos_);
if(opts_.case_sensitive)
{
if(!remaining.starts_with(text))
return false;
}
else
{
if(!ci_starts_with(remaining, text))
return false;
}
pos_ += text.size();
return true;
}
// Match param token - capture until stop_char, '/' or end
bool match_param(std::string const& name, char stop_char = '\0')
{
if(at_end())
return false;
auto start = pos_;
while(pos_ < path_.size() && path_[pos_] != '/')
{
// Stop at delimiter if specified
if(stop_char != '\0' && path_[pos_] == stop_char)
break;
++pos_;
}
// Param must capture at least one character
if(pos_ == start)
return false;
params_.emplace_back(
name,
std::string(path_.substr(start, pos_ - start)));
return true;
}
// Match wildcard token - capture everything to end
bool match_wildcard(std::string const& name)
{
if(at_end())
return false;
auto start = pos_;
pos_ = path_.size();
// Wildcard must capture at least one character
if(pos_ == start)
return false;
params_.emplace_back(
name,
std::string(path_.substr(start)));
return true;
}
// Get the first character of the next meaningful token
// Returns '\0' if none exists or next token is not text
static char
get_stop_char(
std::vector<route_token> const& tokens,
std::size_t next_idx)
{
if(next_idx >= tokens.size())
return '\0';
auto const& next = tokens[next_idx];
if(next.type == route_token_type::text && !next.value.empty())
return next.value[0];
return '\0';
}
// Match a sequence of tokens
bool match_tokens(std::vector<route_token> const& tokens)
{
for(std::size_t i = 0; i < tokens.size(); ++i)
{
if(!match_token(tokens[i], get_stop_char(tokens, i + 1)))
return false;
}
return true;
}
// Match a single token
bool match_token(route_token const& token, char stop_char = '\0')
{
switch(token.type)
{
case route_token_type::text:
return match_text(token.value);
case route_token_type::param:
return match_param(token.value, stop_char);
case route_token_type::wildcard:
return match_wildcard(token.value);
case route_token_type::group:
return match_group(token.children);
default:
return false;
}
}
// Match group - try with contents, then without
bool match_group(std::vector<route_token> const& children)
{
// Save state before trying group
auto saved_pos = pos_;
auto saved_params_size = params_.size();
// Try matching with group contents
if(match_tokens(children))
return true;
// Restore state and try without group
pos_ = saved_pos;
params_.resize(saved_params_size);
return true; // Group is optional, always succeeds if skipped
}
// Check if match is complete based on options
bool is_complete() const
{
if(!opts_.end)
return true; // Prefix match always succeeds
if(opts_.strict)
return at_end();
// Non-strict: allow trailing slash
if(at_end())
return true;
if(pos_ == path_.size() - 1 && path_[pos_] == '/')
return true;
return false;
}
};
} // anonymous namespace
//------------------------------------------------
system::result<route_pattern>
parse_route_pattern(core::string_view pattern)
{
parser p(pattern);
auto rv = p.parse_tokens();
if(rv.has_error())
return rv.error();
route_pattern result;
result.tokens = std::move(rv.value());
result.original = std::string(pattern);
return result;
}
//------------------------------------------------
system::result<match_params>
match_route(
core::string_view path,
route_pattern const& pattern,
match_options const& opts)
{
route_matcher m(path, opts);
if(!m.match_tokens(pattern.tokens))
return grammar::error::mismatch;
if(!m.is_complete())
return grammar::error::mismatch;
match_params result;
result.params = m.params();
result.matched_length = m.pos();
return result;
}
} // detail
} // http
} // boost