1//
2// Copyright (c) 2016-2019 Vinnie Falco (vinnie dot falco at gmail dot com)
3//
4// Distributed under the Boost Software License, Version 1.0. (See accompanying
5// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
6//
7// Official repository: https://github.com/boostorg/beast
8//
9
10#ifndef BOOST_BEAST_HTTP_IMPL_FIELD_IPP
11#define BOOST_BEAST_HTTP_IMPL_FIELD_IPP
12
13#include <boost/beast/http/field.hpp>
14#include <boost/assert.hpp>
15#include <algorithm>
16#include <array>
17#include <cstdint>
18#include <cstring>
19#include <ostream>
20
21
22namespace boost {
23namespace beast {
24namespace http {
25
26namespace detail {
27
28struct field_table
29{
30 static
31 std::uint32_t
32 get_chars(
33 unsigned char const* p) noexcept
34 {
35 // VFALCO memcpy is endian-dependent
36 //std::memcpy(&v, p, 4);
37 // Compiler should be smart enough to
38 // optimize this down to one instruction.
39 return
40 p[0] |
41 (p[1] << 8) |
42 (p[2] << 16) |
43 (p[3] << 24);
44 }
45
46 using array_type =
47 std::array<string_view, 357>;
48
49 // Strings are converted to lowercase
50 static
51 std::uint32_t
52 digest(string_view s)
53 {
54 std::uint32_t r = 0;
55 std::size_t n = s.size();
56 auto p = reinterpret_cast<
57 unsigned char const*>(s.data());
58 // consume N characters at a time
59 // VFALCO Can we do 8 on 64-bit systems?
60 while(n >= 4)
61 {
62 auto const v = get_chars(p);
63 r = (r * 5 + (
64 v | 0x20202020 )); // convert to lower
65 p += 4;
66 n -= 4;
67 }
68 // handle remaining characters
69 while( n > 0 )
70 {
71 r = r * 5 + ( *p | 0x20 );
72 ++p;
73 --n;
74 }
75 return r;
76 }
77
78 // This comparison is case-insensitive, and the
79 // strings must contain only valid http field characters.
80 static
81 bool
82 equals(string_view lhs, string_view rhs)
83 {
84 using Int = std::uint32_t; // VFALCO std::size_t?
85 auto n = lhs.size();
86 if(n != rhs.size())
87 return false;
88 auto p1 = reinterpret_cast<
89 unsigned char const*>(lhs.data());
90 auto p2 = reinterpret_cast<
91 unsigned char const*>(rhs.data());
92 auto constexpr S = sizeof(Int);
93 auto constexpr Mask = static_cast<Int>(
94 0xDFDFDFDFDFDFDFDF & ~Int{0});
95 for(; n >= S; p1 += S, p2 += S, n -= S)
96 {
97 Int const v1 = get_chars(p: p1);
98 Int const v2 = get_chars(p: p2);
99 if((v1 ^ v2) & Mask)
100 return false;
101 }
102 for(; n; ++p1, ++p2, --n)
103 if(( *p1 ^ *p2) & 0xDF)
104 return false;
105 return true;
106 }
107
108 array_type by_name_;
109
110 enum { N = 5155 };
111 unsigned char map_[ N ][ 2 ] = {};
112
113/*
114 From:
115
116 https://www.iana.org/assignments/message-headers/message-headers.xhtml
117*/
118 field_table()
119 : by_name_({._M_elems: {
120// string constants
121 "<unknown-field>",
122 "A-IM",
123 "Accept",
124 "Accept-Additions",
125 "Accept-Charset",
126 "Accept-Datetime",
127 "Accept-Encoding",
128 "Accept-Features",
129 "Accept-Language",
130 "Accept-Patch",
131 "Accept-Post",
132 "Accept-Ranges",
133 "Access-Control",
134 "Access-Control-Allow-Credentials",
135 "Access-Control-Allow-Headers",
136 "Access-Control-Allow-Methods",
137 "Access-Control-Allow-Origin",
138 "Access-Control-Expose-Headers",
139 "Access-Control-Max-Age",
140 "Access-Control-Request-Headers",
141 "Access-Control-Request-Method",
142 "Age",
143 "Allow",
144 "ALPN",
145 "Also-Control",
146 "Alt-Svc",
147 "Alt-Used",
148 "Alternate-Recipient",
149 "Alternates",
150 "Apparently-To",
151 "Apply-To-Redirect-Ref",
152 "Approved",
153 "Archive",
154 "Archived-At",
155 "Article-Names",
156 "Article-Updates",
157 "Authentication-Control",
158 "Authentication-Info",
159 "Authentication-Results",
160 "Authorization",
161 "Auto-Submitted",
162 "Autoforwarded",
163 "Autosubmitted",
164 "Base",
165 "Bcc",
166 "Body",
167 "C-Ext",
168 "C-Man",
169 "C-Opt",
170 "C-PEP",
171 "C-PEP-Info",
172 "Cache-Control",
173 "CalDAV-Timezones",
174 "Cancel-Key",
175 "Cancel-Lock",
176 "Cc",
177 "Close",
178 "Comments",
179 "Compliance",
180 "Connection",
181 "Content-Alternative",
182 "Content-Base",
183 "Content-Description",
184 "Content-Disposition",
185 "Content-Duration",
186 "Content-Encoding",
187 "Content-features",
188 "Content-ID",
189 "Content-Identifier",
190 "Content-Language",
191 "Content-Length",
192 "Content-Location",
193 "Content-MD5",
194 "Content-Range",
195 "Content-Return",
196 "Content-Script-Type",
197 "Content-Style-Type",
198 "Content-Transfer-Encoding",
199 "Content-Type",
200 "Content-Version",
201 "Control",
202 "Conversion",
203 "Conversion-With-Loss",
204 "Cookie",
205 "Cookie2",
206 "Cost",
207 "DASL",
208 "Date",
209 "Date-Received",
210 "DAV",
211 "Default-Style",
212 "Deferred-Delivery",
213 "Delivery-Date",
214 "Delta-Base",
215 "Depth",
216 "Derived-From",
217 "Destination",
218 "Differential-ID",
219 "Digest",
220 "Discarded-X400-IPMS-Extensions",
221 "Discarded-X400-MTS-Extensions",
222 "Disclose-Recipients",
223 "Disposition-Notification-Options",
224 "Disposition-Notification-To",
225 "Distribution",
226 "DKIM-Signature",
227 "DL-Expansion-History",
228 "Downgraded-Bcc",
229 "Downgraded-Cc",
230 "Downgraded-Disposition-Notification-To",
231 "Downgraded-Final-Recipient",
232 "Downgraded-From",
233 "Downgraded-In-Reply-To",
234 "Downgraded-Mail-From",
235 "Downgraded-Message-Id",
236 "Downgraded-Original-Recipient",
237 "Downgraded-Rcpt-To",
238 "Downgraded-References",
239 "Downgraded-Reply-To",
240 "Downgraded-Resent-Bcc",
241 "Downgraded-Resent-Cc",
242 "Downgraded-Resent-From",
243 "Downgraded-Resent-Reply-To",
244 "Downgraded-Resent-Sender",
245 "Downgraded-Resent-To",
246 "Downgraded-Return-Path",
247 "Downgraded-Sender",
248 "Downgraded-To",
249 "EDIINT-Features",
250 "Eesst-Version",
251 "Encoding",
252 "Encrypted",
253 "Errors-To",
254 "ETag",
255 "Expect",
256 "Expires",
257 "Expiry-Date",
258 "Ext",
259 "Followup-To",
260 "Forwarded",
261 "From",
262 "Generate-Delivery-Report",
263 "GetProfile",
264 "Hobareg",
265 "Host",
266 "HTTP2-Settings",
267 "If",
268 "If-Match",
269 "If-Modified-Since",
270 "If-None-Match",
271 "If-Range",
272 "If-Schedule-Tag-Match",
273 "If-Unmodified-Since",
274 "IM",
275 "Importance",
276 "In-Reply-To",
277 "Incomplete-Copy",
278 "Injection-Date",
279 "Injection-Info",
280 "Jabber-ID",
281 "Keep-Alive",
282 "Keywords",
283 "Label",
284 "Language",
285 "Last-Modified",
286 "Latest-Delivery-Time",
287 "Lines",
288 "Link",
289 "List-Archive",
290 "List-Help",
291 "List-ID",
292 "List-Owner",
293 "List-Post",
294 "List-Subscribe",
295 "List-Unsubscribe",
296 "List-Unsubscribe-Post",
297 "Location",
298 "Lock-Token",
299 "Man",
300 "Max-Forwards",
301 "Memento-Datetime",
302 "Message-Context",
303 "Message-ID",
304 "Message-Type",
305 "Meter",
306 "Method-Check",
307 "Method-Check-Expires",
308 "MIME-Version",
309 "MMHS-Acp127-Message-Identifier",
310 "MMHS-Authorizing-Users",
311 "MMHS-Codress-Message-Indicator",
312 "MMHS-Copy-Precedence",
313 "MMHS-Exempted-Address",
314 "MMHS-Extended-Authorisation-Info",
315 "MMHS-Handling-Instructions",
316 "MMHS-Message-Instructions",
317 "MMHS-Message-Type",
318 "MMHS-Originator-PLAD",
319 "MMHS-Originator-Reference",
320 "MMHS-Other-Recipients-Indicator-CC",
321 "MMHS-Other-Recipients-Indicator-To",
322 "MMHS-Primary-Precedence",
323 "MMHS-Subject-Indicator-Codes",
324 "MT-Priority",
325 "Negotiate",
326 "Newsgroups",
327 "NNTP-Posting-Date",
328 "NNTP-Posting-Host",
329 "Non-Compliance",
330 "Obsoletes",
331 "Opt",
332 "Optional",
333 "Optional-WWW-Authenticate",
334 "Ordering-Type",
335 "Organization",
336 "Origin",
337 "Original-Encoded-Information-Types",
338 "Original-From",
339 "Original-Message-ID",
340 "Original-Recipient",
341 "Original-Sender",
342 "Original-Subject",
343 "Originator-Return-Address",
344 "Overwrite",
345 "P3P",
346 "Path",
347 "PEP",
348 "Pep-Info",
349 "PICS-Label",
350 "Position",
351 "Posting-Version",
352 "Pragma",
353 "Prefer",
354 "Preference-Applied",
355 "Prevent-NonDelivery-Report",
356 "Priority",
357 "Privicon",
358 "ProfileObject",
359 "Protocol",
360 "Protocol-Info",
361 "Protocol-Query",
362 "Protocol-Request",
363 "Proxy-Authenticate",
364 "Proxy-Authentication-Info",
365 "Proxy-Authorization",
366 "Proxy-Connection",
367 "Proxy-Features",
368 "Proxy-Instruction",
369 "Public",
370 "Public-Key-Pins",
371 "Public-Key-Pins-Report-Only",
372 "Range",
373 "Received",
374 "Received-SPF",
375 "Redirect-Ref",
376 "References",
377 "Referer",
378 "Referer-Root",
379 "Relay-Version",
380 "Reply-By",
381 "Reply-To",
382 "Require-Recipient-Valid-Since",
383 "Resent-Bcc",
384 "Resent-Cc",
385 "Resent-Date",
386 "Resent-From",
387 "Resent-Message-ID",
388 "Resent-Reply-To",
389 "Resent-Sender",
390 "Resent-To",
391 "Resolution-Hint",
392 "Resolver-Location",
393 "Retry-After",
394 "Return-Path",
395 "Safe",
396 "Schedule-Reply",
397 "Schedule-Tag",
398 "Sec-Fetch-Dest",
399 "Sec-Fetch-Mode",
400 "Sec-Fetch-Site",
401 "Sec-Fetch-User",
402 "Sec-WebSocket-Accept",
403 "Sec-WebSocket-Extensions",
404 "Sec-WebSocket-Key",
405 "Sec-WebSocket-Protocol",
406 "Sec-WebSocket-Version",
407 "Security-Scheme",
408 "See-Also",
409 "Sender",
410 "Sensitivity",
411 "Server",
412 "Set-Cookie",
413 "Set-Cookie2",
414 "SetProfile",
415 "SIO-Label",
416 "SIO-Label-History",
417 "SLUG",
418 "SoapAction",
419 "Solicitation",
420 "Status-URI",
421 "Strict-Transport-Security",
422 "Subject",
423 "SubOK",
424 "Subst",
425 "Summary",
426 "Supersedes",
427 "Surrogate-Capability",
428 "Surrogate-Control",
429 "TCN",
430 "TE",
431 "Timeout",
432 "Title",
433 "To",
434 "Topic",
435 "Trailer",
436 "Transfer-Encoding",
437 "TTL",
438 "UA-Color",
439 "UA-Media",
440 "UA-Pixels",
441 "UA-Resolution",
442 "UA-Windowpixels",
443 "Upgrade",
444 "Urgency",
445 "URI",
446 "User-Agent",
447 "Variant-Vary",
448 "Vary",
449 "VBR-Info",
450 "Version",
451 "Via",
452 "Want-Digest",
453 "Warning",
454 "WWW-Authenticate",
455 "X-Archived-At",
456 "X-Device-Accept",
457 "X-Device-Accept-Charset",
458 "X-Device-Accept-Encoding",
459 "X-Device-Accept-Language",
460 "X-Device-User-Agent",
461 "X-Frame-Options",
462 "X-Mittente",
463 "X-PGP-Sig",
464 "X-Ricevuta",
465 "X-Riferimento-Message-ID",
466 "X-TipoRicevuta",
467 "X-Trasporto",
468 "X-VerificaSicurezza",
469 "X400-Content-Identifier",
470 "X400-Content-Return",
471 "X400-Content-Type",
472 "X400-MTS-Identifier",
473 "X400-Originator",
474 "X400-Received",
475 "X400-Recipients",
476 "X400-Trace",
477 "Xref"
478 }})
479 {
480 for(std::size_t i = 1, n = 256; i < n; ++i)
481 {
482 auto sv = by_name_[ i ];
483 auto h = digest(s: sv);
484 auto j = h % N;
485 BOOST_ASSERT(map_[j][0] == 0);
486 map_[j][0] = static_cast<unsigned char>(i);
487 }
488
489 for(std::size_t i = 256, n = by_name_.size(); i < n; ++i)
490 {
491 auto sv = by_name_[i];
492 auto h = digest(s: sv);
493 auto j = h % N;
494 BOOST_ASSERT(map_[j][1] == 0);
495 map_[j][1] = static_cast<unsigned char>(i - 255);
496 }
497 }
498
499 field
500 string_to_field(string_view s) const
501 {
502 auto h = digest(s);
503 auto j = h % N;
504 int i = map_[j][0];
505 string_view s2 = by_name_[i];
506 if(i != 0 && equals(lhs: s, rhs: s2))
507 return static_cast<field>(i);
508 i = map_[j][1];
509 if(i == 0)
510 return field::unknown;
511 i += 255;
512 s2 = by_name_[i];
513
514 if(equals(lhs: s, rhs: s2))
515 return static_cast<field>(i);
516 return field::unknown;
517 }
518
519 //
520 // Deprecated
521 //
522
523 using const_iterator =
524 array_type::const_iterator;
525
526 std::size_t
527 size() const
528 {
529 return by_name_.size();
530 }
531
532 const_iterator
533 begin() const
534 {
535 return by_name_.begin();
536 }
537
538 const_iterator
539 end() const
540 {
541 return by_name_.end();
542 }
543};
544
545BOOST_BEAST_DECL
546field_table const&
547get_field_table()
548{
549 static field_table const tab;
550 return tab;
551}
552
553BOOST_BEAST_DECL
554string_view
555to_string(field f)
556{
557 auto const& v = get_field_table();
558 BOOST_ASSERT(static_cast<unsigned>(f) < v.size());
559 return v.begin()[static_cast<unsigned>(f)];
560}
561
562} // detail
563
564string_view
565to_string(field f)
566{
567 return detail::to_string(f);
568}
569
570field
571string_to_field(string_view s)
572{
573 return detail::get_field_table().string_to_field(s);
574}
575
576std::ostream&
577operator<<(std::ostream& os, field f)
578{
579 return os << to_string(f);
580}
581
582} // http
583} // beast
584} // boost
585
586#endif
587

source code of boost/libs/beast/include/boost/beast/http/impl/field.ipp