add any_allocator

CMakeLists.txt

@@ -64,6 +64,7 @@ function(boost_url_setup_properties target)
             Boost::align
             Boost::assert
             Boost::config
+            Boost::core
             Boost::exception
             Boost::mp11
             Boost::system

doc/qbk/quickref.xml

@@ -25,6 +25,7 @@
       <entry valign="top">
         <bridgehead renderas="sect3">Classes</bridgehead>
         <simplelist type="vert" columns="1">
+          <member><link linkend="url.ref.boost__urls__any_allocator">any_allocator</link></member>
           <member><link linkend="url.ref.boost__urls__authority_view">authority_view</link></member>
           <member><link linkend="url.ref.boost__urls__ipv4_address">ipv4_address</link></member>
           <member><link linkend="url.ref.boost__urls__ipv6_address">ipv6_address</link></member>

include/boost/url/any_allocator.hpp

@@ -0,0 +1,124 @@
+//
+// Copyright (c) 2022 Alan Freitas (alandefreitas@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/url
+//
+
+#ifndef BOOST_URL_ANY_ALLOCATOR_HPP
+#define BOOST_URL_ANY_ALLOCATOR_HPP
+
+#include <boost/url/detail/any_allocator.hpp>
+#include <boost/url/detail/config.hpp>
+
+#include <memory>
+#include <type_traits>
+
+namespace boost {
+namespace urls {
+
+/** A type-erased allocator with shared ownership.
+
+    This type satisfies the requirements for
+   <em>Allocator</em>
+
+    @par Specification
+    @li <a href="https://en.cppreference.com/w/cpp/named_req/Allocator">Allocator (cppreference.com)</a>
+
+ */
+#ifdef BOOST_URL_DOCS
+template <class T>
+using any_allocator = __see_below__;
+#else
+template <class T>
+class any_allocator
+    : private detail::any_allocator_base
+{
+    std::shared_ptr<base> p_;
+
+    template <class U>
+    friend class any_allocator;
+
+public:
+    using value_type      = T;
+
+    using size_type       = std::size_t;
+
+    using difference_type = std::ptrdiff_t;
+
+    using reference       = value_type&;
+
+    using const_reference = value_type const&;
+
+    using pointer         = value_type*;
+
+    using const_pointer   = value_type const*;
+
+    template <class U>
+    struct rebind
+    {
+        using other = any_allocator<U>;
+    };
+
+    using is_always_equal = std::false_type;
+
+#ifndef BOOST_URL_NO_GCC_4_2_WORKAROUND
+    any_allocator()       = default;
+#endif
+
+    any_allocator(any_allocator const&) = default;
+
+    template <class U>
+    explicit any_allocator(
+        any_allocator<U> const& other) noexcept;
+
+    template <class Allocator>
+    explicit any_allocator(Allocator const& a);
+
+    any_allocator&
+    operator=(any_allocator const&)
+        = default;
+
+    T*
+    allocate(std::size_t n) const;
+
+    void
+    deallocate(T* p, std::size_t n);
+
+    template <class U, class... Args>
+    void
+    construct(U* p, Args&&... args);
+
+    template <class U>
+    void
+    destroy(U* p);
+
+    friend bool
+    operator==(const any_allocator& a,
+               const any_allocator& b) noexcept
+    {
+        return (a.p_ == b.p_)
+               || (a.p_ != nullptr
+                   && b.p_ != nullptr
+                   && (a.p_->type_id
+                           == b.p_->type_id
+                       && a.p_->is_equal(*b.p_)));
+    }
+
+    friend bool
+    operator!=(const any_allocator& a,
+               const any_allocator& b) noexcept
+    {
+        return !(a == b);
+    }
+};
+#endif
+
+} // namespace urls
+} // namespace boost
+
+#include <boost/url/impl/any_allocator.hpp>
+
+#endif