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|---|---|---|---|
| 1 | // | ||
| 2 | // Copyright (c) 2025 Vinnie Falco (vinnie.falco@gmail.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/cppalliance/buffers | ||
| 8 | // | ||
| 9 | |||
| 10 | #ifndef BOOST_BUFFERS_SLICE_HPP | ||
| 11 | #define BOOST_BUFFERS_SLICE_HPP | ||
| 12 | |||
| 13 | #include <boost/buffers/detail/config.hpp> | ||
| 14 | #include <boost/buffers/buffer.hpp> | ||
| 15 | #include <boost/buffers/range.hpp> | ||
| 16 | #include <boost/assert.hpp> | ||
| 17 | #include <array> | ||
| 18 | #include <iterator> | ||
| 19 | #include <type_traits> | ||
| 20 | |||
| 21 | namespace boost { | ||
| 22 | namespace buffers { | ||
| 23 | |||
| 24 | template<class T> class slice_of; | ||
| 25 | |||
| 26 | namespace detail { | ||
| 27 | |||
| 28 | template<class T, class = void> | ||
| 29 | struct has_tag_invoke : std::false_type {}; | ||
| 30 | |||
| 31 | template<class T> | ||
| 32 | struct has_tag_invoke<T, decltype(tag_invoke( | ||
| 33 | std::declval<slice_tag const&>(), | ||
| 34 | std::declval<T&>(), | ||
| 35 | std::declval<slice_how>(), | ||
| 36 | std::declval<std::size_t>()))> | ||
| 37 | : std::true_type {}; | ||
| 38 | |||
| 39 | } // detail | ||
| 40 | |||
| 41 | /** Alias for the type representing a slice of T | ||
| 42 | */ | ||
| 43 | template<class T> | ||
| 44 | using slice_type = typename std::conditional< | ||
| 45 | detail::has_tag_invoke<T>::value, | ||
| 46 | T, slice_of<T> >::type; | ||
| 47 | |||
| 48 | //------------------------------------------------ | ||
| 49 | |||
| 50 | /** A wrapper enabling a buffer sequence to be consumed | ||
| 51 | */ | ||
| 52 | template<class BufferSequence> | ||
| 53 | class slice_of | ||
| 54 | { | ||
| 55 | static_assert(! std::is_const<BufferSequence>::value, | ||
| 56 | "BufferSequence can't be const"); | ||
| 57 | |||
| 58 | static_assert(! std::is_reference<BufferSequence>::value, | ||
| 59 | "BufferSequence can't be a reference"); | ||
| 60 | |||
| 61 | static_assert(is_const_buffer_sequence<BufferSequence>::value, | ||
| 62 | "BufferSequence does not meet type requirements"); | ||
| 63 | |||
| 64 | using iter_type = decltype( | ||
| 65 | std::declval<BufferSequence const&>().begin()); | ||
| 66 | |||
| 67 | using difference_type = | ||
| 68 | typename std::iterator_traits<iter_type>::difference_type; | ||
| 69 | |||
| 70 | BufferSequence bs_; | ||
| 71 | difference_type begin_ = 0; // index of first buffer in sequence | ||
| 72 | difference_type end_ = 0; // 1 + index of last buffer in sequence | ||
| 73 | std::size_t len_ = 0; // length of bs_ | ||
| 74 | std::size_t size_ = 0; // total bytes | ||
| 75 | std::size_t prefix_ = 0; // used prefix bytes | ||
| 76 | std::size_t suffix_ = 0; // used suffix bytes | ||
| 77 | |||
| 78 | public: | ||
| 79 | /** The type of values returned by iterators | ||
| 80 | */ | ||
| 81 | using value_type = typename std::conditional< | ||
| 82 | is_mutable_buffer_sequence<BufferSequence>::value, | ||
| 83 | mutable_buffer, const_buffer>::type; | ||
| 84 | |||
| 85 | /** The type of returned iterators | ||
| 86 | */ | ||
| 87 | class const_iterator; | ||
| 88 | |||
| 89 | /** Constructor | ||
| 90 | */ | ||
| 91 | 44 | slice_of() = default; | |
| 92 | |||
| 93 | /** Constructor | ||
| 94 | */ | ||
| 95 | 279218 | slice_of( | |
| 96 | BufferSequence const& bs) | ||
| 97 | 279218 | : bs_(bs) | |
| 98 | { | ||
| 99 | 279218 | iter_type it = buffers::begin(bs_); | |
| 100 | 279218 | iter_type eit = buffers::end(bs_); | |
| 101 | 279218 | begin_ = 0; | |
| 102 | 279626 | end_ = std::distance(it, eit); | |
| 103 |
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837750 | while(it != eit) |
| 104 | { | ||
| 105 | 558532 | value_type b(*it); | |
| 106 | 558532 | size_ += b.size(); | |
| 107 | 558532 | ++len_; | |
| 108 | 558532 | ++it; | |
| 109 | } | ||
| 110 | 279218 | } | |
| 111 | |||
| 112 | /** Return an iterator to the beginning of the sequence | ||
| 113 | */ | ||
| 114 | const_iterator | ||
| 115 | begin() const noexcept; | ||
| 116 | |||
| 117 | /** Return an iterator to the end of the sequence | ||
| 118 | */ | ||
| 119 | const_iterator | ||
| 120 | end() const noexcept; | ||
| 121 | |||
| 122 | friend | ||
| 123 | void | ||
| 124 | 267363 | tag_invoke( | |
| 125 | slice_tag const&, | ||
| 126 | slice_of<BufferSequence>& bs, | ||
| 127 | slice_how how, | ||
| 128 | std::size_t n) | ||
| 129 | { | ||
| 130 | 267363 | bs.slice_impl(how, n); | |
| 131 | 267363 | } | |
| 132 | |||
| 133 | private: | ||
| 134 | iter_type | ||
| 135 | 3458845 | begin_iter_impl() const noexcept | |
| 136 | { | ||
| 137 | 3458845 | iter_type it = buffers::begin(bs_); | |
| 138 | 3458845 | std::advance(it, begin_); | |
| 139 | 3458845 | return it; | |
| 140 | } | ||
| 141 | |||
| 142 | iter_type | ||
| 143 | 3327213 | end_iter_impl() const noexcept | |
| 144 | { | ||
| 145 | 3327213 | iter_type it = buffers::begin(bs_); | |
| 146 | 3327213 | std::advance(it, end_); | |
| 147 | 3327213 | return it; | |
| 148 | } | ||
| 149 | |||
| 150 | void | ||
| 151 | 131628 | remove_prefix_impl( | |
| 152 | std::size_t n) | ||
| 153 | { | ||
| 154 |
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131628 | if(n > size_) |
| 155 | 4135 | n = size_; | |
| 156 | |||
| 157 | // nice hack to simplify the loop (M. Nejati) | ||
| 158 | 131628 | n += prefix_; | |
| 159 | 131628 | size_ += prefix_; | |
| 160 | 131628 | prefix_ = 0; | |
| 161 | |||
| 162 | 131628 | iter_type it = begin_iter_impl(); | |
| 163 | |||
| 164 |
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200787 | while(n > 0 && begin_ != end_) |
| 165 | { | ||
| 166 | 177988 | value_type b = *it; | |
| 167 |
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177988 | if(n < b.size()) |
| 168 | { | ||
| 169 | 108829 | prefix_ = n; | |
| 170 | 108829 | size_ -= n; | |
| 171 | 108829 | break; | |
| 172 | } | ||
| 173 | 69159 | n -= b.size(); | |
| 174 | 69159 | size_ -= b.size(); | |
| 175 | 69159 | ++begin_; | |
| 176 | 69159 | ++it; | |
| 177 | 69159 | --len_; | |
| 178 | } | ||
| 179 | 131628 | } | |
| 180 | |||
| 181 | void | ||
| 182 | 115125 | remove_suffix_impl( | |
| 183 | std::size_t n) | ||
| 184 | { | ||
| 185 |
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115125 | if(size_ == 0) |
| 186 | { | ||
| 187 | ✗ | BOOST_ASSERT(begin_ == end_); | |
| 188 | 115125 | return; | |
| 189 | } | ||
| 190 |
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115125 | BOOST_ASSERT(begin_ != end_); |
| 191 | |||
| 192 |
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115125 | if(n > size_) |
| 193 | ✗ | n = size_; | |
| 194 | |||
| 195 | 115125 | n += suffix_; | |
| 196 | 115125 | size_ += suffix_; | |
| 197 | 115125 | suffix_ = 0; | |
| 198 | |||
| 199 | 115125 | iter_type bit = begin_iter_impl(); | |
| 200 | 115125 | iter_type it = end_iter_impl(); | |
| 201 | 115125 | it--; | |
| 202 | |||
| 203 |
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189344 | while(it != bit) |
| 204 | { | ||
| 205 | 115144 | value_type b = *it; | |
| 206 |
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115144 | if(n < b.size()) |
| 207 | { | ||
| 208 | 40925 | suffix_ = n; | |
| 209 | 40925 | size_ -= n; | |
| 210 | 40925 | return; | |
| 211 | } | ||
| 212 | 74219 | n -= b.size(); | |
| 213 | 74219 | size_ -= b.size(); | |
| 214 | 74219 | --it; | |
| 215 | 74219 | --end_; | |
| 216 | 74219 | --len_; | |
| 217 | } | ||
| 218 | 74200 | value_type b = *it; | |
| 219 | 74200 | auto m = b.size() - prefix_; | |
| 220 |
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74200 | if(n < m) |
| 221 | { | ||
| 222 | 74200 | suffix_ = n; | |
| 223 | 74200 | size_ -= n; | |
| 224 | 74200 | return; | |
| 225 | } | ||
| 226 | ✗ | end_ = begin_; | |
| 227 | ✗ | len_ = 0; | |
| 228 | ✗ | size_ = 0; | |
| 229 | 288 | } | |
| 230 | |||
| 231 | void | ||
| 232 | 135735 | keep_prefix_impl( | |
| 233 | std::size_t n) | ||
| 234 | { | ||
| 235 |
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135735 | if(n >= size_) |
| 236 | 8249 | return; | |
| 237 |
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127486 | if(n == 0) |
| 238 | { | ||
| 239 | 12361 | end_ = begin_; | |
| 240 | 12361 | len_ = 0; | |
| 241 | 12361 | size_ = 0; | |
| 242 | 12361 | return; | |
| 243 | } | ||
| 244 | 115125 | remove_suffix_impl(size_ - n); | |
| 245 | } | ||
| 246 | |||
| 247 | void | ||
| 248 | keep_suffix_impl( | ||
| 249 | std::size_t n) | ||
| 250 | { | ||
| 251 | if(n >= size_) | ||
| 252 | return; | ||
| 253 | if(n == 0) | ||
| 254 | { | ||
| 255 | begin_ = end_; | ||
| 256 | len_ = 0; | ||
| 257 | size_ = 0; | ||
| 258 | return; | ||
| 259 | } | ||
| 260 | remove_prefix_impl(size_ - n); | ||
| 261 | } | ||
| 262 | |||
| 263 | void | ||
| 264 | 267363 | slice_impl( | |
| 265 | slice_how how, | ||
| 266 | std::size_t n) | ||
| 267 | { | ||
| 268 |
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267363 | switch(how) |
| 269 | { | ||
| 270 | 131628 | case slice_how::remove_prefix: | |
| 271 | { | ||
| 272 | 131628 | remove_prefix_impl(n); | |
| 273 | 131628 | break; | |
| 274 | } | ||
| 275 | 135735 | case slice_how::keep_prefix: | |
| 276 | { | ||
| 277 | 135735 | keep_prefix_impl(n); | |
| 278 | 135735 | break; | |
| 279 | } | ||
| 280 | } | ||
| 281 | 267363 | } | |
| 282 | }; | ||
| 283 | |||
| 284 | //------------------------------------------------ | ||
| 285 | |||
| 286 | template<class BufferSequence> | ||
| 287 | class slice_of<BufferSequence>:: | ||
| 288 | const_iterator | ||
| 289 | { | ||
| 290 | using iter_type = typename | ||
| 291 | slice_of::iter_type; | ||
| 292 | |||
| 293 | iter_type it_; | ||
| 294 | // VFALCO we could just point back to | ||
| 295 | // the original sequence to save size | ||
| 296 | std::size_t prefix_ = 0; | ||
| 297 | std::size_t suffix_ = 0; | ||
| 298 | std::size_t i_ = 0; | ||
| 299 | std::size_t n_ = 0; | ||
| 300 | |||
| 301 | friend class slice_of<BufferSequence>; | ||
| 302 | |||
| 303 | 6424180 | const_iterator( | |
| 304 | iter_type it, | ||
| 305 | std::size_t prefix__, | ||
| 306 | std::size_t suffix__, | ||
| 307 | std::size_t i, | ||
| 308 | std::size_t n) noexcept | ||
| 309 | 6424180 | : it_(it) | |
| 310 | 6424180 | , prefix_(prefix__) | |
| 311 | 6424180 | , suffix_(suffix__) | |
| 312 | 6424180 | , i_(i) | |
| 313 | 6424180 | , n_(n) | |
| 314 | { | ||
| 315 | // n_ is the index of the end iterator | ||
| 316 | 6424180 | } | |
| 317 | |||
| 318 | public: | ||
| 319 | using value_type = typename slice_of::value_type; | ||
| 320 | using reference = value_type; | ||
| 321 | using pointer = void; | ||
| 322 | using difference_type = std::ptrdiff_t; | ||
| 323 | using iterator_category = | ||
| 324 | std::bidirectional_iterator_tag; | ||
| 325 | #if defined(__cpp_concepts) || defined(__cpp_lib_concepts) | ||
| 326 | using iterator_concept = std::bidirectional_iterator_tag; // (since C++20) | ||
| 327 | #endif | ||
| 328 | |||
| 329 | const_iterator() = default; | ||
| 330 | |||
| 331 | bool | ||
| 332 | 7790311 | operator==( | |
| 333 | const_iterator const& other) const noexcept | ||
| 334 | { | ||
| 335 | return | ||
| 336 | 10995425 | it_ == other.it_ && | |
| 337 |
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3212088 | prefix_ == other.prefix_ && |
| 338 |
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3212088 | suffix_ == other.suffix_ && |
| 339 |
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14214487 | i_ == other.i_ && |
| 340 |
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11002399 | n_ == other.n_; |
| 341 | } | ||
| 342 | |||
| 343 | bool | ||
| 344 | 7790311 | operator!=( | |
| 345 | const_iterator const& other) const noexcept | ||
| 346 | { | ||
| 347 | 7790311 | return !(*this == other); | |
| 348 | } | ||
| 349 | |||
| 350 | reference | ||
| 351 | 4578223 | operator*() const noexcept | |
| 352 | { | ||
| 353 | 4578223 | value_type v = *it_; | |
| 354 | using P = typename std::conditional< | ||
| 355 | is_mutable_buffer_sequence<BufferSequence>::value, | ||
| 356 | char*, char const*>::type; | ||
| 357 | 4578223 | auto p = reinterpret_cast<P>(v.data()); | |
| 358 | 4578223 | auto n = v.size(); | |
| 359 |
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4578223 | if(i_ == 0) |
| 360 | { | ||
| 361 | 2971974 | p += prefix_; | |
| 362 | 2971974 | n -= prefix_; | |
| 363 | } | ||
| 364 |
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4578223 | if(i_ == n_ - 1) |
| 365 | 2971974 | n -= suffix_; | |
| 366 | 4578223 | return value_type(p, n); | |
| 367 | } | ||
| 368 | |||
| 369 | const_iterator& | ||
| 370 | 3015721 | operator++() noexcept | |
| 371 | { | ||
| 372 |
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3015721 | BOOST_ASSERT(i_ < n_); |
| 373 | 3015721 | ++it_; | |
| 374 | 3015721 | ++i_; | |
| 375 | 3015721 | return *this; | |
| 376 | } | ||
| 377 | |||
| 378 | const_iterator | ||
| 379 | 781252 | operator++(int) noexcept | |
| 380 | { | ||
| 381 | 781252 | auto temp = *this; | |
| 382 | 781252 | ++(*this); | |
| 383 | 781252 | return temp; | |
| 384 | } | ||
| 385 | |||
| 386 | const_iterator& | ||
| 387 | 1562504 | operator--() noexcept | |
| 388 | { | ||
| 389 |
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1562504 | BOOST_ASSERT(i_ > 0); |
| 390 | 1562504 | --it_; | |
| 391 | 1562504 | --i_; | |
| 392 | 1562504 | return *this; | |
| 393 | } | ||
| 394 | |||
| 395 | const_iterator | ||
| 396 | 781252 | operator--(int) noexcept | |
| 397 | { | ||
| 398 | 781252 | auto temp = *this; | |
| 399 | 781252 | --(*this); | |
| 400 | 781252 | return temp; | |
| 401 | } | ||
| 402 | }; | ||
| 403 | |||
| 404 | //------------------------------------------------ | ||
| 405 | |||
| 406 | template<class BufferSequence> | ||
| 407 | auto | ||
| 408 | 3212092 | slice_of<BufferSequence>:: | |
| 409 | begin() const noexcept -> | ||
| 410 | const_iterator | ||
| 411 | { | ||
| 412 | return const_iterator( | ||
| 413 | 3212092 | begin_iter_impl(), prefix_, suffix_, 0, len_); | |
| 414 | } | ||
| 415 | |||
| 416 | template<class BufferSequence> | ||
| 417 | auto | ||
| 418 | 3212088 | slice_of<BufferSequence>:: | |
| 419 | end() const noexcept -> | ||
| 420 | const_iterator | ||
| 421 | { | ||
| 422 | return const_iterator( | ||
| 423 | 3212088 | end_iter_impl(), prefix_, suffix_, len_, len_); | |
| 424 | } | ||
| 425 | |||
| 426 | //------------------------------------------------ | ||
| 427 | |||
| 428 | // in-place modify return value | ||
| 429 | // ----------------------------- | ||
| 430 | // keep_prefix* prefix | ||
| 431 | // keep_suffix suffix | ||
| 432 | // remove_prefix* sans_prefix | ||
| 433 | // remove_suffix sans_suffix | ||
| 434 | |||
| 435 | /** Remove all but the first `n` bytes from a buffer sequence | ||
| 436 | */ | ||
| 437 | constexpr struct keep_prefix_mrdocs_workaround_t | ||
| 438 | { | ||
| 439 | template<class BufferSequence> | ||
| 440 | 413096 | auto operator()( | |
| 441 | BufferSequence& bs, | ||
| 442 | std::size_t n) const -> typename std::enable_if< | ||
| 443 | is_const_buffer_sequence<BufferSequence>::value && | ||
| 444 | detail::has_tag_invoke<BufferSequence>::value>::type | ||
| 445 | |||
| 446 | { | ||
| 447 |
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413096 | tag_invoke(slice_tag{}, bs, slice_how::keep_prefix, n); |
| 448 | 413096 | } | |
| 449 | } const keep_prefix{}; | ||
| 450 | |||
| 451 | /** Remove all but the last `n` bytes from a buffer sequence | ||
| 452 | */ | ||
| 453 | constexpr struct keep_suffix_mrdocs_workaround_t | ||
| 454 | { | ||
| 455 | template<class BufferSequence> | ||
| 456 | 140520 | auto operator()( | |
| 457 | BufferSequence& bs, | ||
| 458 | std::size_t n) const -> typename std::enable_if< | ||
| 459 | is_const_buffer_sequence<BufferSequence>::value && | ||
| 460 | detail::has_tag_invoke<BufferSequence>::value>::type | ||
| 461 | { | ||
| 462 | 140520 | auto n0 = size(bs); | |
| 463 |
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140520 | if(n < n0) |
| 464 |
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123974 | tag_invoke(slice_tag{}, bs, slice_how::remove_prefix, n0 - n); |
| 465 | 140520 | } | |
| 466 | } const keep_suffix{}; | ||
| 467 | |||
| 468 | /** Remove `n` bytes from the beginning of a buffer sequence | ||
| 469 | */ | ||
| 470 | constexpr struct remove_prefix_mrdocs_workaround_t | ||
| 471 | { | ||
| 472 | template<class BufferSequence> | ||
| 473 | 405083 | auto operator()( | |
| 474 | BufferSequence& bs, | ||
| 475 | std::size_t n) const -> typename std::enable_if< | ||
| 476 | is_const_buffer_sequence<BufferSequence>::value && | ||
| 477 | detail::has_tag_invoke<BufferSequence>::value>::type | ||
| 478 | { | ||
| 479 |
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405083 | tag_invoke(slice_tag{}, bs, slice_how::remove_prefix, n); |
| 480 | 405083 | } | |
| 481 | } const remove_prefix{}; | ||
| 482 | |||
| 483 | /** Remove `n` bytes from the end of a buffer sequence | ||
| 484 | */ | ||
| 485 | constexpr struct remove_suffix_mrdocs_workaround_t | ||
| 486 | { | ||
| 487 | template<class BufferSequence> | ||
| 488 | 140774 | auto operator()( | |
| 489 | BufferSequence& bs, | ||
| 490 | std::size_t n) const -> typename std::enable_if< | ||
| 491 | is_const_buffer_sequence<BufferSequence>::value && | ||
| 492 | detail::has_tag_invoke<BufferSequence>::value>::type | ||
| 493 | { | ||
| 494 | 140774 | auto n0 = size(bs); | |
| 495 |
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140774 | if(n > 0) |
| 496 | { | ||
| 497 |
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132479 | if( n > n0) |
| 498 | 8295 | n = n0; | |
| 499 |
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132479 | tag_invoke(slice_tag{}, bs, slice_how::keep_prefix, n0 - n); |
| 500 | } | ||
| 501 | 140774 | } | |
| 502 | } const remove_suffix{}; | ||
| 503 | |||
| 504 | //------------------------------------------------ | ||
| 505 | |||
| 506 | /** Return a sequence representing the first `n` bytes of a buffer sequence | ||
| 507 | */ | ||
| 508 | constexpr struct prefix_mrdocs_workaround_t | ||
| 509 | { | ||
| 510 | template<class BufferSequence> | ||
| 511 | 108 | auto operator()( | |
| 512 | BufferSequence const& bs, | ||
| 513 | std::size_t n) const noexcept -> typename std::enable_if< | ||
| 514 | is_const_buffer_sequence<BufferSequence>::value, | ||
| 515 | slice_type<BufferSequence>>::type | ||
| 516 | { | ||
| 517 | 108 | slice_type<BufferSequence> result(bs); | |
| 518 | 108 | keep_prefix(result, n); | |
| 519 | 108 | return result; | |
| 520 | } | ||
| 521 | } prefix{}; | ||
| 522 | |||
| 523 | /** Return a sequence representing the last `n` bytes of a buffer sequence | ||
| 524 | */ | ||
| 525 | constexpr struct suffix_mrdocs_workaround_t | ||
| 526 | { | ||
| 527 | template<class BufferSequence> | ||
| 528 | auto operator()( | ||
| 529 | BufferSequence const& bs, | ||
| 530 | std::size_t n) const noexcept -> typename std::enable_if< | ||
| 531 | is_const_buffer_sequence<BufferSequence>::value, | ||
| 532 | slice_type<BufferSequence>>::type | ||
| 533 | { | ||
| 534 | slice_type<BufferSequence> result(bs); | ||
| 535 | keep_suffix(result, n); | ||
| 536 | return result; | ||
| 537 | } | ||
| 538 | } suffix{}; | ||
| 539 | |||
| 540 | /** Return a sequence representing all but the first `n` bytes of a buffer sequence | ||
| 541 | */ | ||
| 542 | constexpr struct sans_prefix_mrdocs_workaround_t | ||
| 543 | { | ||
| 544 | template<class BufferSequence> | ||
| 545 | 117 | auto operator()( | |
| 546 | BufferSequence const& bs, | ||
| 547 | std::size_t n) const noexcept -> typename std::enable_if< | ||
| 548 | is_const_buffer_sequence<BufferSequence>::value, | ||
| 549 | slice_type<BufferSequence>>::type | ||
| 550 | { | ||
| 551 | 117 | slice_type<BufferSequence> result(bs); | |
| 552 | 117 | remove_prefix(result, n); | |
| 553 | 117 | return result; | |
| 554 | } | ||
| 555 | } sans_prefix{}; | ||
| 556 | |||
| 557 | /** Return a sequence representing all but the last `n` bytes of a buffer sequence | ||
| 558 | */ | ||
| 559 | constexpr struct sans_suffix_mrdocs_workaround_t | ||
| 560 | { | ||
| 561 | template<class BufferSequence> | ||
| 562 | auto operator()( | ||
| 563 | BufferSequence const& bs, | ||
| 564 | std::size_t n) const noexcept -> typename std::enable_if< | ||
| 565 | is_const_buffer_sequence<BufferSequence>::value, | ||
| 566 | slice_type<BufferSequence>>::type | ||
| 567 | { | ||
| 568 | slice_type<BufferSequence> result(bs); | ||
| 569 | remove_suffix(result, n); | ||
| 570 | return result; | ||
| 571 | } | ||
| 572 | } sans_suffix{}; | ||
| 573 | |||
| 574 | } // buffers | ||
| 575 | } // boost | ||
| 576 | |||
| 577 | #endif | ||
| 578 |