Beast.Asio:

New classes:

  class async_completion:
    Helper class for implementing asynchronous initiation functions.
    See n3964:
        Library Foundations for Asynchronous Operations, Revision 1
        http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2014/n3964.pdf

  class basic_streambuf:
    Meets the requirements of Streambuf.

  class buffered_readstream:
    Buffers a ReadStream with a ConstBufferSequence.

  class consuming_buffers:
    Adapts a BufferSequence which wraps the underlying buffer
    sequence and presents fewer bytes, with the retained bytes
    occurring at the end of the sequence.

  class handler_alloc:
    A C++ Allocator the uses asio handler allocation hooks.

  class static_streambuf:
    An implementation of the Streambuf concept that uses a
    fixed size buffer with size determined at compile-time.

  class streambuf_readstream:
    Buffers a ReadStream with a Streambuf.

New functions:

  append_buffers()
    Returns a new BufferSequence which efficiently concatenates
    two or more buffer sequences together.

  prepare_buffers()
    Shortens a buffer sequence. The bytes excluded are at the
    end of the underlying buffer sequence.

  boost::asio::read_until()
    A copy of boost::asio::read_until overloads, modified to work
    with a beast::asio::basic_streambuf.

Debugging:

  buffers_to_string()

    Convert a ConstBufferSequence to a human readable string
    suitable for diagnostics.

type_check.h:

  Metafunctions for checking asio concepts:
    AsyncReadStream, AsyncWriteStream
    SyncReadStream, SyncWriteStream
    ConstBufferSequence, MutableBufferSequence
    Streambuf
    Handler

Changes:

* All symbols moved up a namespace level.
* streambuf provides all move and copy special members,
  behavior of moved from objects is well-defined.

Fixes:

* Fix basic_streambuf iterator category.

beast/asio/handler_alloc.h

@@ -0,0 +1,150 @@
+//------------------------------------------------------------------------------
+/*
+    This file is part of Beast: https://github.com/vinniefalco/Beast
+    Copyright 2013, Vinnie Falco <vinnie.falco@gmail.com>
+
+    Permission to use, copy, modify, and/or distribute this software for any
+    purpose  with  or without fee is hereby granted, provided that the above
+    copyright notice and this permission notice appear in all copies.
+
+    THE  SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+    WITH  REGARD  TO  THIS  SOFTWARE  INCLUDING  ALL  IMPLIED  WARRANTIES  OF
+    MERCHANTABILITY  AND  FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+    ANY  SPECIAL ,  DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+    WHATSOEVER  RESULTING  FROM  LOSS  OF USE, DATA OR PROFITS, WHETHER IN AN
+    ACTION  OF  CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+    OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+//==============================================================================
+
+#ifndef BEAST_ASIO_HANDLER_ALLOC_H_INCLUDED
+#define BEAST_ASIO_HANDLER_ALLOC_H_INCLUDED
+
+#include <boost/asio/detail/handler_alloc_helpers.hpp>
+#include <cstdlib>
+#include <memory>
+#include <type_traits>
+#include <utility>
+
+namespace beast {
+
+// Guidance from
+// http://howardhinnant.github.io/allocator_boilerplate.html
+
+/** An allocator that uses handler customizations.
+
+    This allocator uses the handler customizations `asio_handler_allocate`
+    and `asio_handler_deallocate` to manage memory.
+
+    @tparam T The type of object
+
+    @tparam Handler The type of handler.
+*/
+template <class T, class Handler>
+class handler_alloc
+{
+private:
+    // We want a partial template specialization as a friend
+    // but that isn't allowed so we friend all versions. This
+    // should produce a compile error if Handler is not
+    // constructible from H.
+    //
+    template <class U, class H>
+    friend class handler_alloc;
+
+    Handler h_;
+
+public:
+    using value_type = T;
+    using is_always_equal = std::true_type;
+
+    handler_alloc() = delete;
+    handler_alloc(handler_alloc&&) = default;
+    handler_alloc(handler_alloc const&) = default;
+    handler_alloc& operator=(handler_alloc&&) = default;
+    handler_alloc& operator=(handler_alloc const&) = default;
+
+    /** Construct the allocator.
+
+        The handler is moved or copied into the allocator.
+    */
+    explicit
+    handler_alloc(Handler&& h)
+        : h_(std::move(h))
+    {
+    }
+
+    /** Construct the allocator.
+
+        A copy of the handler is made.
+    */
+    explicit
+    handler_alloc(Handler const& h)
+        : h_(h)
+    {
+    }
+
+    template<class U>
+    handler_alloc(
+            handler_alloc<U, Handler>&& other)
+        : h_(std::move(other.h_))
+    {
+    }
+
+    template<class U>
+    handler_alloc(
+            handler_alloc<U, Handler> const& other)
+        : h_(other.h_)
+    {
+    }
+
+    value_type*
+    allocate(std::ptrdiff_t n)
+    {
+        auto const size = n * sizeof(T);
+        return static_cast<value_type*>(
+            boost_asio_handler_alloc_helpers::allocate(
+                size, h_));
+    }
+
+    void
+    deallocate(value_type* p, std::ptrdiff_t n)
+    {
+        auto const size = n * sizeof(T);
+        boost_asio_handler_alloc_helpers::deallocate(
+            p, size, h_);
+    }
+
+#ifdef _MSC_VER
+    // Work-around for MSVC not using allocator_traits
+    // in the implementation of shared_ptr
+    //
+    void
+    destroy(T* t)
+    {
+        t->~T();
+    }
+#endif
+
+    template<class U>
+    friend
+    bool
+    operator==(handler_alloc const& lhs,
+        handler_alloc<U, Handler> const& rhs)
+    {
+        return true;
+    }
+
+    template<class U>
+    friend
+    bool
+    operator!=(handler_alloc const& lhs,
+        handler_alloc<U, Handler> const& rhs)
+    {
+        return !(lhs == rhs);
+    }
+};
+
+} // beast
+
+#endif