整理

include/boost/smart_ptr/allocate_local_shared_array.hpp

@@ -0,0 +1,180 @@
+/*
+Copyright 2017-2019 Glen Joseph Fernandes
+(glenjofe@gmail.com)
+
+Distributed under the Boost Software License, Version 1.0.
+(http://www.boost.org/LICENSE_1_0.txt)
+*/
+#ifndef BOOST_SMART_PTR_ALLOCATE_LOCAL_SHARED_ARRAY_HPP
+#define BOOST_SMART_PTR_ALLOCATE_LOCAL_SHARED_ARRAY_HPP
+
+#include <boost/smart_ptr/allocate_shared_array.hpp>
+#include <boost/smart_ptr/local_shared_ptr.hpp>
+#include <boost/smart_ptr/detail/sp_type_traits.hpp>
+#include <type_traits>
+
+namespace boost {
+namespace detail {
+
+class BOOST_SYMBOL_VISIBLE lsp_array_base
+    : public local_counted_base {
+public:
+    void set(sp_counted_base* base) noexcept {
+        count_ = shared_count(base);
+    }
+
+    void local_cb_destroy() noexcept override {
+        shared_count().swap(count_);
+    }
+
+    shared_count local_cb_get_shared_count() const
+        noexcept override {
+        return count_;
+    }
+
+private:
+    shared_count count_;
+};
+
+template<class A>
+class lsp_array_state
+    : public sp_array_state<A> {
+public:
+    template<class U>
+    lsp_array_state(const U& other, std::size_t size) noexcept
+        : sp_array_state<A>(other, size) { }
+
+    lsp_array_base& base() noexcept {
+        return base_;
+    }
+
+private:
+    lsp_array_base base_;
+};
+
+template<class A, std::size_t N>
+class lsp_size_array_state
+    : public sp_size_array_state<A, N> {
+public:
+    template<class U>
+    lsp_size_array_state(const U& other, std::size_t size) noexcept
+        : sp_size_array_state<A, N>(other, size) { }
+
+    lsp_array_base& base() noexcept {
+        return base_;
+    }
+
+private:
+    lsp_array_base base_;
+};
+
+} /* detail */
+
+template<class T, class A>
+inline typename std::enable_if<detail::sp_is_unbounded_array<T>::value,
+    local_shared_ptr<T> >::type
+allocate_local_shared(const A& allocator, std::size_t count)
+{
+    typedef typename detail::sp_array_element<T>::type element;
+    typedef typename allocator_rebind<A, element>::type other;
+    typedef detail::lsp_array_state<other> state;
+    typedef detail::sp_array_base<state> base;
+    detail::sp_array_result<other, base> result(allocator, count);
+    base* node = result.get();
+    element* start = detail::sp_array_start<element>(node);
+    ::new(static_cast<void*>(node)) base(allocator, start, count);
+    detail::lsp_array_base& local = node->state().base();
+    local.set(node);
+    result.release();
+    return local_shared_ptr<T>(detail::lsp_internal_constructor_tag(), start,
+        &local);
+}
+
+template<class T, class A>
+inline typename std::enable_if<detail::sp_is_bounded_array<T>::value,
+    local_shared_ptr<T> >::type
+allocate_local_shared(const A& allocator)
+{
+    enum {
+        count = std::extent<T>::value
+    };
+    typedef typename detail::sp_array_element<T>::type element;
+    typedef typename allocator_rebind<A, element>::type other;
+    typedef detail::lsp_size_array_state<other, count> state;
+    typedef detail::sp_array_base<state> base;
+    detail::sp_array_result<other, base> result(allocator, count);
+    base* node = result.get();
+    element* start = detail::sp_array_start<element>(node);
+    ::new(static_cast<void*>(node)) base(allocator, start, count);
+    detail::lsp_array_base& local = node->state().base();
+    local.set(node);
+    result.release();
+    return local_shared_ptr<T>(detail::lsp_internal_constructor_tag(), start,
+        &local);
+}
+
+template<class T, class A>
+inline typename std::enable_if<detail::sp_is_unbounded_array<T>::value,
+    local_shared_ptr<T> >::type
+allocate_local_shared(const A& allocator, std::size_t count,
+    const typename std::remove_extent<T>::type& value)
+{
+    typedef typename detail::sp_array_element<T>::type element;
+    typedef typename allocator_rebind<A, element>::type other;
+    typedef detail::lsp_array_state<other> state;
+    typedef detail::sp_array_base<state> base;
+    detail::sp_array_result<other, base> result(allocator, count);
+    base* node = result.get();
+    element* start = detail::sp_array_start<element>(node);
+    ::new(static_cast<void*>(node)) base(allocator, start, count, value);
+    detail::lsp_array_base& local = node->state().base();
+    local.set(node);
+    result.release();
+    return local_shared_ptr<T>(detail::lsp_internal_constructor_tag(), start,
+        &local);
+}
+
+template<class T, class A>
+inline typename std::enable_if<detail::sp_is_bounded_array<T>::value,
+    local_shared_ptr<T> >::type
+allocate_local_shared(const A& allocator,
+    const typename std::remove_extent<T>::type& value)
+{
+    enum {
+        count = std::extent<T>::value
+    };
+    typedef typename detail::sp_array_element<T>::type element;
+    typedef typename allocator_rebind<A, element>::type other;
+    typedef detail::lsp_size_array_state<other, count> state;
+    typedef detail::sp_array_base<state> base;
+    detail::sp_array_result<other, base> result(allocator, count);
+    base* node = result.get();
+    element* start = detail::sp_array_start<element>(node);
+    ::new(static_cast<void*>(node)) base(allocator, start, count, value);
+    detail::lsp_array_base& local = node->state().base();
+    local.set(node);
+    result.release();
+    return local_shared_ptr<T>(detail::lsp_internal_constructor_tag(), start,
+        &local);
+}
+
+template<class T, class A>
+inline typename std::enable_if<detail::sp_is_unbounded_array<T>::value,
+    local_shared_ptr<T> >::type
+allocate_local_shared_noinit(const A& allocator, std::size_t count)
+{
+    return boost::allocate_local_shared<T>(boost::noinit_adapt(allocator),
+        count);
+}
+
+template<class T, class A>
+inline typename std::enable_if<detail::sp_is_bounded_array<T>::value,
+    local_shared_ptr<T> >::type
+allocate_local_shared_noinit(const A& allocator)
+{
+    return boost::allocate_local_shared<T>(boost::noinit_adapt(allocator));
+}
+
+} /* boost */
+
+#endif