buffer_sequence_adapter.hpp 19 KB

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  1. //
  2. // detail/buffer_sequence_adapter.hpp
  3. // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  4. //
  5. // Copyright (c) 2003-2024 Christopher M. Kohlhoff (chris at kohlhoff dot com)
  6. //
  7. // Distributed under the Boost Software License, Version 1.0. (See accompanying
  8. // file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
  9. //
  10. #ifndef BOOST_ASIO_DETAIL_BUFFER_SEQUENCE_ADAPTER_HPP
  11. #define BOOST_ASIO_DETAIL_BUFFER_SEQUENCE_ADAPTER_HPP
  12. #if defined(_MSC_VER) && (_MSC_VER >= 1200)
  13. # pragma once
  14. #endif // defined(_MSC_VER) && (_MSC_VER >= 1200)
  15. #include <boost/asio/detail/config.hpp>
  16. #include <boost/asio/buffer.hpp>
  17. #include <boost/asio/detail/array_fwd.hpp>
  18. #include <boost/asio/detail/socket_types.hpp>
  19. #include <boost/asio/registered_buffer.hpp>
  20. #include <boost/asio/detail/push_options.hpp>
  21. namespace boost {
  22. namespace asio {
  23. namespace detail {
  24. class buffer_sequence_adapter_base
  25. {
  26. #if defined(BOOST_ASIO_WINDOWS_RUNTIME)
  27. public:
  28. // The maximum number of buffers to support in a single operation.
  29. enum { max_buffers = 1 };
  30. protected:
  31. typedef Windows::Storage::Streams::IBuffer^ native_buffer_type;
  32. BOOST_ASIO_DECL static void init_native_buffer(
  33. native_buffer_type& buf,
  34. const boost::asio::mutable_buffer& buffer);
  35. BOOST_ASIO_DECL static void init_native_buffer(
  36. native_buffer_type& buf,
  37. const boost::asio::const_buffer& buffer);
  38. #elif defined(BOOST_ASIO_WINDOWS) || defined(__CYGWIN__)
  39. public:
  40. // The maximum number of buffers to support in a single operation.
  41. enum { max_buffers = 64 < max_iov_len ? 64 : max_iov_len };
  42. protected:
  43. typedef WSABUF native_buffer_type;
  44. static void init_native_buffer(WSABUF& buf,
  45. const boost::asio::mutable_buffer& buffer)
  46. {
  47. buf.buf = static_cast<char*>(buffer.data());
  48. buf.len = static_cast<ULONG>(buffer.size());
  49. }
  50. static void init_native_buffer(WSABUF& buf,
  51. const boost::asio::const_buffer& buffer)
  52. {
  53. buf.buf = const_cast<char*>(static_cast<const char*>(buffer.data()));
  54. buf.len = static_cast<ULONG>(buffer.size());
  55. }
  56. #else // defined(BOOST_ASIO_WINDOWS) || defined(__CYGWIN__)
  57. public:
  58. // The maximum number of buffers to support in a single operation.
  59. enum { max_buffers = 64 < max_iov_len ? 64 : max_iov_len };
  60. protected:
  61. typedef iovec native_buffer_type;
  62. static void init_iov_base(void*& base, void* addr)
  63. {
  64. base = addr;
  65. }
  66. template <typename T>
  67. static void init_iov_base(T& base, void* addr)
  68. {
  69. base = static_cast<T>(addr);
  70. }
  71. static void init_native_buffer(iovec& iov,
  72. const boost::asio::mutable_buffer& buffer)
  73. {
  74. init_iov_base(iov.iov_base, buffer.data());
  75. iov.iov_len = buffer.size();
  76. }
  77. static void init_native_buffer(iovec& iov,
  78. const boost::asio::const_buffer& buffer)
  79. {
  80. init_iov_base(iov.iov_base, const_cast<void*>(buffer.data()));
  81. iov.iov_len = buffer.size();
  82. }
  83. #endif // defined(BOOST_ASIO_WINDOWS) || defined(__CYGWIN__)
  84. };
  85. // Helper class to translate buffers into the native buffer representation.
  86. template <typename Buffer, typename Buffers>
  87. class buffer_sequence_adapter
  88. : buffer_sequence_adapter_base
  89. {
  90. public:
  91. enum { is_single_buffer = false };
  92. enum { is_registered_buffer = false };
  93. explicit buffer_sequence_adapter(const Buffers& buffer_sequence)
  94. : count_(0), total_buffer_size_(0)
  95. {
  96. buffer_sequence_adapter::init(
  97. boost::asio::buffer_sequence_begin(buffer_sequence),
  98. boost::asio::buffer_sequence_end(buffer_sequence));
  99. }
  100. native_buffer_type* buffers()
  101. {
  102. return buffers_;
  103. }
  104. std::size_t count() const
  105. {
  106. return count_;
  107. }
  108. std::size_t total_size() const
  109. {
  110. return total_buffer_size_;
  111. }
  112. registered_buffer_id registered_id() const
  113. {
  114. return registered_buffer_id();
  115. }
  116. bool all_empty() const
  117. {
  118. return total_buffer_size_ == 0;
  119. }
  120. static bool all_empty(const Buffers& buffer_sequence)
  121. {
  122. return buffer_sequence_adapter::all_empty(
  123. boost::asio::buffer_sequence_begin(buffer_sequence),
  124. boost::asio::buffer_sequence_end(buffer_sequence));
  125. }
  126. static void validate(const Buffers& buffer_sequence)
  127. {
  128. buffer_sequence_adapter::validate(
  129. boost::asio::buffer_sequence_begin(buffer_sequence),
  130. boost::asio::buffer_sequence_end(buffer_sequence));
  131. }
  132. static Buffer first(const Buffers& buffer_sequence)
  133. {
  134. return buffer_sequence_adapter::first(
  135. boost::asio::buffer_sequence_begin(buffer_sequence),
  136. boost::asio::buffer_sequence_end(buffer_sequence));
  137. }
  138. enum { linearisation_storage_size = 8192 };
  139. static Buffer linearise(const Buffers& buffer_sequence,
  140. const boost::asio::mutable_buffer& storage)
  141. {
  142. return buffer_sequence_adapter::linearise(
  143. boost::asio::buffer_sequence_begin(buffer_sequence),
  144. boost::asio::buffer_sequence_end(buffer_sequence), storage);
  145. }
  146. private:
  147. template <typename Iterator>
  148. void init(Iterator begin, Iterator end)
  149. {
  150. Iterator iter = begin;
  151. for (; iter != end && count_ < max_buffers; ++iter, ++count_)
  152. {
  153. Buffer buffer(*iter);
  154. init_native_buffer(buffers_[count_], buffer);
  155. total_buffer_size_ += buffer.size();
  156. }
  157. }
  158. template <typename Iterator>
  159. static bool all_empty(Iterator begin, Iterator end)
  160. {
  161. Iterator iter = begin;
  162. std::size_t i = 0;
  163. for (; iter != end && i < max_buffers; ++iter, ++i)
  164. if (Buffer(*iter).size() > 0)
  165. return false;
  166. return true;
  167. }
  168. template <typename Iterator>
  169. static void validate(Iterator begin, Iterator end)
  170. {
  171. Iterator iter = begin;
  172. for (; iter != end; ++iter)
  173. {
  174. Buffer buffer(*iter);
  175. buffer.data();
  176. }
  177. }
  178. template <typename Iterator>
  179. static Buffer first(Iterator begin, Iterator end)
  180. {
  181. Iterator iter = begin;
  182. for (; iter != end; ++iter)
  183. {
  184. Buffer buffer(*iter);
  185. if (buffer.size() != 0)
  186. return buffer;
  187. }
  188. return Buffer();
  189. }
  190. template <typename Iterator>
  191. static Buffer linearise(Iterator begin, Iterator end,
  192. const boost::asio::mutable_buffer& storage)
  193. {
  194. boost::asio::mutable_buffer unused_storage = storage;
  195. Iterator iter = begin;
  196. while (iter != end && unused_storage.size() != 0)
  197. {
  198. Buffer buffer(*iter);
  199. ++iter;
  200. if (buffer.size() == 0)
  201. continue;
  202. if (unused_storage.size() == storage.size())
  203. {
  204. if (iter == end)
  205. return buffer;
  206. if (buffer.size() >= unused_storage.size())
  207. return buffer;
  208. }
  209. unused_storage += boost::asio::buffer_copy(unused_storage, buffer);
  210. }
  211. return Buffer(storage.data(), storage.size() - unused_storage.size());
  212. }
  213. native_buffer_type buffers_[max_buffers];
  214. std::size_t count_;
  215. std::size_t total_buffer_size_;
  216. };
  217. template <typename Buffer>
  218. class buffer_sequence_adapter<Buffer, boost::asio::mutable_buffer>
  219. : buffer_sequence_adapter_base
  220. {
  221. public:
  222. enum { is_single_buffer = true };
  223. enum { is_registered_buffer = false };
  224. explicit buffer_sequence_adapter(
  225. const boost::asio::mutable_buffer& buffer_sequence)
  226. {
  227. init_native_buffer(buffer_, Buffer(buffer_sequence));
  228. total_buffer_size_ = buffer_sequence.size();
  229. }
  230. native_buffer_type* buffers()
  231. {
  232. return &buffer_;
  233. }
  234. std::size_t count() const
  235. {
  236. return 1;
  237. }
  238. std::size_t total_size() const
  239. {
  240. return total_buffer_size_;
  241. }
  242. registered_buffer_id registered_id() const
  243. {
  244. return registered_buffer_id();
  245. }
  246. bool all_empty() const
  247. {
  248. return total_buffer_size_ == 0;
  249. }
  250. static bool all_empty(const boost::asio::mutable_buffer& buffer_sequence)
  251. {
  252. return buffer_sequence.size() == 0;
  253. }
  254. static void validate(const boost::asio::mutable_buffer& buffer_sequence)
  255. {
  256. buffer_sequence.data();
  257. }
  258. static Buffer first(const boost::asio::mutable_buffer& buffer_sequence)
  259. {
  260. return Buffer(buffer_sequence);
  261. }
  262. enum { linearisation_storage_size = 1 };
  263. static Buffer linearise(const boost::asio::mutable_buffer& buffer_sequence,
  264. const Buffer&)
  265. {
  266. return Buffer(buffer_sequence);
  267. }
  268. private:
  269. native_buffer_type buffer_;
  270. std::size_t total_buffer_size_;
  271. };
  272. template <typename Buffer>
  273. class buffer_sequence_adapter<Buffer, boost::asio::const_buffer>
  274. : buffer_sequence_adapter_base
  275. {
  276. public:
  277. enum { is_single_buffer = true };
  278. enum { is_registered_buffer = false };
  279. explicit buffer_sequence_adapter(
  280. const boost::asio::const_buffer& buffer_sequence)
  281. {
  282. init_native_buffer(buffer_, Buffer(buffer_sequence));
  283. total_buffer_size_ = buffer_sequence.size();
  284. }
  285. native_buffer_type* buffers()
  286. {
  287. return &buffer_;
  288. }
  289. std::size_t count() const
  290. {
  291. return 1;
  292. }
  293. std::size_t total_size() const
  294. {
  295. return total_buffer_size_;
  296. }
  297. registered_buffer_id registered_id() const
  298. {
  299. return registered_buffer_id();
  300. }
  301. bool all_empty() const
  302. {
  303. return total_buffer_size_ == 0;
  304. }
  305. static bool all_empty(const boost::asio::const_buffer& buffer_sequence)
  306. {
  307. return buffer_sequence.size() == 0;
  308. }
  309. static void validate(const boost::asio::const_buffer& buffer_sequence)
  310. {
  311. buffer_sequence.data();
  312. }
  313. static Buffer first(const boost::asio::const_buffer& buffer_sequence)
  314. {
  315. return Buffer(buffer_sequence);
  316. }
  317. enum { linearisation_storage_size = 1 };
  318. static Buffer linearise(const boost::asio::const_buffer& buffer_sequence,
  319. const Buffer&)
  320. {
  321. return Buffer(buffer_sequence);
  322. }
  323. private:
  324. native_buffer_type buffer_;
  325. std::size_t total_buffer_size_;
  326. };
  327. #if !defined(BOOST_ASIO_NO_DEPRECATED)
  328. template <typename Buffer>
  329. class buffer_sequence_adapter<Buffer, boost::asio::mutable_buffers_1>
  330. : buffer_sequence_adapter_base
  331. {
  332. public:
  333. enum { is_single_buffer = true };
  334. enum { is_registered_buffer = false };
  335. explicit buffer_sequence_adapter(
  336. const boost::asio::mutable_buffers_1& buffer_sequence)
  337. {
  338. init_native_buffer(buffer_, Buffer(buffer_sequence));
  339. total_buffer_size_ = buffer_sequence.size();
  340. }
  341. native_buffer_type* buffers()
  342. {
  343. return &buffer_;
  344. }
  345. std::size_t count() const
  346. {
  347. return 1;
  348. }
  349. std::size_t total_size() const
  350. {
  351. return total_buffer_size_;
  352. }
  353. registered_buffer_id registered_id() const
  354. {
  355. return registered_buffer_id();
  356. }
  357. bool all_empty() const
  358. {
  359. return total_buffer_size_ == 0;
  360. }
  361. static bool all_empty(const boost::asio::mutable_buffers_1& buffer_sequence)
  362. {
  363. return buffer_sequence.size() == 0;
  364. }
  365. static void validate(const boost::asio::mutable_buffers_1& buffer_sequence)
  366. {
  367. buffer_sequence.data();
  368. }
  369. static Buffer first(const boost::asio::mutable_buffers_1& buffer_sequence)
  370. {
  371. return Buffer(buffer_sequence);
  372. }
  373. enum { linearisation_storage_size = 1 };
  374. static Buffer linearise(const boost::asio::mutable_buffers_1& buffer_sequence,
  375. const Buffer&)
  376. {
  377. return Buffer(buffer_sequence);
  378. }
  379. private:
  380. native_buffer_type buffer_;
  381. std::size_t total_buffer_size_;
  382. };
  383. template <typename Buffer>
  384. class buffer_sequence_adapter<Buffer, boost::asio::const_buffers_1>
  385. : buffer_sequence_adapter_base
  386. {
  387. public:
  388. enum { is_single_buffer = true };
  389. enum { is_registered_buffer = false };
  390. explicit buffer_sequence_adapter(
  391. const boost::asio::const_buffers_1& buffer_sequence)
  392. {
  393. init_native_buffer(buffer_, Buffer(buffer_sequence));
  394. total_buffer_size_ = buffer_sequence.size();
  395. }
  396. native_buffer_type* buffers()
  397. {
  398. return &buffer_;
  399. }
  400. std::size_t count() const
  401. {
  402. return 1;
  403. }
  404. std::size_t total_size() const
  405. {
  406. return total_buffer_size_;
  407. }
  408. registered_buffer_id registered_id() const
  409. {
  410. return registered_buffer_id();
  411. }
  412. bool all_empty() const
  413. {
  414. return total_buffer_size_ == 0;
  415. }
  416. static bool all_empty(const boost::asio::const_buffers_1& buffer_sequence)
  417. {
  418. return buffer_sequence.size() == 0;
  419. }
  420. static void validate(const boost::asio::const_buffers_1& buffer_sequence)
  421. {
  422. buffer_sequence.data();
  423. }
  424. static Buffer first(const boost::asio::const_buffers_1& buffer_sequence)
  425. {
  426. return Buffer(buffer_sequence);
  427. }
  428. enum { linearisation_storage_size = 1 };
  429. static Buffer linearise(const boost::asio::const_buffers_1& buffer_sequence,
  430. const Buffer&)
  431. {
  432. return Buffer(buffer_sequence);
  433. }
  434. private:
  435. native_buffer_type buffer_;
  436. std::size_t total_buffer_size_;
  437. };
  438. #endif // !defined(BOOST_ASIO_NO_DEPRECATED)
  439. template <typename Buffer>
  440. class buffer_sequence_adapter<Buffer, boost::asio::mutable_registered_buffer>
  441. : buffer_sequence_adapter_base
  442. {
  443. public:
  444. enum { is_single_buffer = true };
  445. enum { is_registered_buffer = true };
  446. explicit buffer_sequence_adapter(
  447. const boost::asio::mutable_registered_buffer& buffer_sequence)
  448. {
  449. init_native_buffer(buffer_, buffer_sequence.buffer());
  450. total_buffer_size_ = buffer_sequence.size();
  451. registered_id_ = buffer_sequence.id();
  452. }
  453. native_buffer_type* buffers()
  454. {
  455. return &buffer_;
  456. }
  457. std::size_t count() const
  458. {
  459. return 1;
  460. }
  461. std::size_t total_size() const
  462. {
  463. return total_buffer_size_;
  464. }
  465. registered_buffer_id registered_id() const
  466. {
  467. return registered_id_;
  468. }
  469. bool all_empty() const
  470. {
  471. return total_buffer_size_ == 0;
  472. }
  473. static bool all_empty(
  474. const boost::asio::mutable_registered_buffer& buffer_sequence)
  475. {
  476. return buffer_sequence.size() == 0;
  477. }
  478. static void validate(
  479. const boost::asio::mutable_registered_buffer& buffer_sequence)
  480. {
  481. buffer_sequence.data();
  482. }
  483. static Buffer first(
  484. const boost::asio::mutable_registered_buffer& buffer_sequence)
  485. {
  486. return Buffer(buffer_sequence.buffer());
  487. }
  488. enum { linearisation_storage_size = 1 };
  489. static Buffer linearise(
  490. const boost::asio::mutable_registered_buffer& buffer_sequence,
  491. const Buffer&)
  492. {
  493. return Buffer(buffer_sequence.buffer());
  494. }
  495. private:
  496. native_buffer_type buffer_;
  497. std::size_t total_buffer_size_;
  498. registered_buffer_id registered_id_;
  499. };
  500. template <typename Buffer>
  501. class buffer_sequence_adapter<Buffer, boost::asio::const_registered_buffer>
  502. : buffer_sequence_adapter_base
  503. {
  504. public:
  505. enum { is_single_buffer = true };
  506. enum { is_registered_buffer = true };
  507. explicit buffer_sequence_adapter(
  508. const boost::asio::const_registered_buffer& buffer_sequence)
  509. {
  510. init_native_buffer(buffer_, buffer_sequence.buffer());
  511. total_buffer_size_ = buffer_sequence.size();
  512. registered_id_ = buffer_sequence.id();
  513. }
  514. native_buffer_type* buffers()
  515. {
  516. return &buffer_;
  517. }
  518. std::size_t count() const
  519. {
  520. return 1;
  521. }
  522. std::size_t total_size() const
  523. {
  524. return total_buffer_size_;
  525. }
  526. registered_buffer_id registered_id() const
  527. {
  528. return registered_id_;
  529. }
  530. bool all_empty() const
  531. {
  532. return total_buffer_size_ == 0;
  533. }
  534. static bool all_empty(
  535. const boost::asio::const_registered_buffer& buffer_sequence)
  536. {
  537. return buffer_sequence.size() == 0;
  538. }
  539. static void validate(
  540. const boost::asio::const_registered_buffer& buffer_sequence)
  541. {
  542. buffer_sequence.data();
  543. }
  544. static Buffer first(
  545. const boost::asio::const_registered_buffer& buffer_sequence)
  546. {
  547. return Buffer(buffer_sequence.buffer());
  548. }
  549. enum { linearisation_storage_size = 1 };
  550. static Buffer linearise(
  551. const boost::asio::const_registered_buffer& buffer_sequence,
  552. const Buffer&)
  553. {
  554. return Buffer(buffer_sequence.buffer());
  555. }
  556. private:
  557. native_buffer_type buffer_;
  558. std::size_t total_buffer_size_;
  559. registered_buffer_id registered_id_;
  560. };
  561. template <typename Buffer, typename Elem>
  562. class buffer_sequence_adapter<Buffer, boost::array<Elem, 2>>
  563. : buffer_sequence_adapter_base
  564. {
  565. public:
  566. enum { is_single_buffer = false };
  567. enum { is_registered_buffer = false };
  568. explicit buffer_sequence_adapter(
  569. const boost::array<Elem, 2>& buffer_sequence)
  570. {
  571. init_native_buffer(buffers_[0], Buffer(buffer_sequence[0]));
  572. init_native_buffer(buffers_[1], Buffer(buffer_sequence[1]));
  573. total_buffer_size_ = buffer_sequence[0].size() + buffer_sequence[1].size();
  574. }
  575. native_buffer_type* buffers()
  576. {
  577. return buffers_;
  578. }
  579. std::size_t count() const
  580. {
  581. return 2;
  582. }
  583. std::size_t total_size() const
  584. {
  585. return total_buffer_size_;
  586. }
  587. registered_buffer_id registered_id() const
  588. {
  589. return registered_buffer_id();
  590. }
  591. bool all_empty() const
  592. {
  593. return total_buffer_size_ == 0;
  594. }
  595. static bool all_empty(const boost::array<Elem, 2>& buffer_sequence)
  596. {
  597. return buffer_sequence[0].size() == 0 && buffer_sequence[1].size() == 0;
  598. }
  599. static void validate(const boost::array<Elem, 2>& buffer_sequence)
  600. {
  601. buffer_sequence[0].data();
  602. buffer_sequence[1].data();
  603. }
  604. static Buffer first(const boost::array<Elem, 2>& buffer_sequence)
  605. {
  606. return Buffer(buffer_sequence[0].size() != 0
  607. ? buffer_sequence[0] : buffer_sequence[1]);
  608. }
  609. enum { linearisation_storage_size = 8192 };
  610. static Buffer linearise(const boost::array<Elem, 2>& buffer_sequence,
  611. const boost::asio::mutable_buffer& storage)
  612. {
  613. if (buffer_sequence[0].size() == 0)
  614. return Buffer(buffer_sequence[1]);
  615. if (buffer_sequence[1].size() == 0)
  616. return Buffer(buffer_sequence[0]);
  617. return Buffer(storage.data(),
  618. boost::asio::buffer_copy(storage, buffer_sequence));
  619. }
  620. private:
  621. native_buffer_type buffers_[2];
  622. std::size_t total_buffer_size_;
  623. };
  624. template <typename Buffer, typename Elem>
  625. class buffer_sequence_adapter<Buffer, std::array<Elem, 2>>
  626. : buffer_sequence_adapter_base
  627. {
  628. public:
  629. enum { is_single_buffer = false };
  630. enum { is_registered_buffer = false };
  631. explicit buffer_sequence_adapter(
  632. const std::array<Elem, 2>& buffer_sequence)
  633. {
  634. init_native_buffer(buffers_[0], Buffer(buffer_sequence[0]));
  635. init_native_buffer(buffers_[1], Buffer(buffer_sequence[1]));
  636. total_buffer_size_ = buffer_sequence[0].size() + buffer_sequence[1].size();
  637. }
  638. native_buffer_type* buffers()
  639. {
  640. return buffers_;
  641. }
  642. std::size_t count() const
  643. {
  644. return 2;
  645. }
  646. std::size_t total_size() const
  647. {
  648. return total_buffer_size_;
  649. }
  650. registered_buffer_id registered_id() const
  651. {
  652. return registered_buffer_id();
  653. }
  654. bool all_empty() const
  655. {
  656. return total_buffer_size_ == 0;
  657. }
  658. static bool all_empty(const std::array<Elem, 2>& buffer_sequence)
  659. {
  660. return buffer_sequence[0].size() == 0 && buffer_sequence[1].size() == 0;
  661. }
  662. static void validate(const std::array<Elem, 2>& buffer_sequence)
  663. {
  664. buffer_sequence[0].data();
  665. buffer_sequence[1].data();
  666. }
  667. static Buffer first(const std::array<Elem, 2>& buffer_sequence)
  668. {
  669. return Buffer(buffer_sequence[0].size() != 0
  670. ? buffer_sequence[0] : buffer_sequence[1]);
  671. }
  672. enum { linearisation_storage_size = 8192 };
  673. static Buffer linearise(const std::array<Elem, 2>& buffer_sequence,
  674. const boost::asio::mutable_buffer& storage)
  675. {
  676. if (buffer_sequence[0].size() == 0)
  677. return Buffer(buffer_sequence[1]);
  678. if (buffer_sequence[1].size() == 0)
  679. return Buffer(buffer_sequence[0]);
  680. return Buffer(storage.data(),
  681. boost::asio::buffer_copy(storage, buffer_sequence));
  682. }
  683. private:
  684. native_buffer_type buffers_[2];
  685. std::size_t total_buffer_size_;
  686. };
  687. } // namespace detail
  688. } // namespace asio
  689. } // namespace boost
  690. #include <boost/asio/detail/pop_options.hpp>
  691. #if defined(BOOST_ASIO_HEADER_ONLY)
  692. # include <boost/asio/detail/impl/buffer_sequence_adapter.ipp>
  693. #endif // defined(BOOST_ASIO_HEADER_ONLY)
  694. #endif // BOOST_ASIO_DETAIL_BUFFER_SEQUENCE_ADAPTER_HPP