Move construct and destroy from Smart_Ptr to Core

doc/alloc_construct.qbk

@@ -0,0 +1,125 @@
+[/
+Copyright 2019 Glen Joseph Fernandes
+(glenjofe@gmail.com)
+
+Distributed under the Boost Software License, Version 1.0.
+(http://www.boost.org/LICENSE_1_0.txt)
+]
+
+[section:alloc_construct alloc_construct]
+
+[simplesect Authors]
+
+* Glen Fernandes
+
+[endsimplesect]
+
+[section Overview]
+
+The header <boost/core/alloc_construct.hpp> provides function templates
+`alloc_construct`, `alloc_construct_n`, `alloc_destroy`, and `alloc_destroy_n`
+for allocator aware and exception safe construction and destruction of objects
+and arrays.
+
+[endsect]
+
+[section Example]
+
+The following example allocates storage for an array of `n` elements of `T`
+using an allocator `a` and constructs `T` elements in that storage. If any
+exception was thrown during construction of an element, the constructed
+elements are destroyed in reverse order.
+
+```
+template<class A>
+auto create(A& a, std::size_t n)
+{
+    auto p = a.allocate(n);
+    try {
+        boost::alloc_construct_n(a, boost::to_address(p), n);
+    } catch (...) {
+        a.deallocate(n);
+        throw;
+    }
+    return p;
+}
+```
+
+[endsect]
+
+[section Reference]
+
+```
+namespace boost {
+
+template<class A, class T>
+void alloc_destroy(A& a, T* p);
+
+template<class A, class T>
+void alloc_destroy_n(A& a, T* p, std::size_t n);
+
+template<class A, class T, class U>
+void alloc_construct(A& a, T* p, U&&... u);
+
+template<class A, class T>
+void alloc_construct_n(A& a, T* p, std::size_t n);
+
+template<class A, class T>
+void alloc_construct_n(A& a, T* p, std::size_t n, const T* l, std::size_t m);
+
+} /* boost */
+```
+
+[section Functions]
+
+[variablelist
+[[`template<class A, class T> void alloc_destroy(A& a, T* p);`]
+[[variablelist
+[[Requires][`A` is an _Allocator_]]
+[[Effects][`std::allocator_traits<A>::destroy(a, p)`.]]]]]
+[[`template<class A, class T> void alloc_destroy_n(A& a, T* p,
+std::size_t n);`]
+[[variablelist
+[[Requires][`A` is an _Allocator_]]
+[[Effects]
+[Destroys each element in reverse order by calling
+`std::allocator_traits<A>::destroy(a, &p[i])`.]]]]]
+[[`template<class A, class T, class U> void alloc_construct(A& a, T* p,
+U&&... u);`]
+[[variablelist
+[[Requires][`A` is an _Allocator_]]
+[[Effects]
+[`std::allocator_traits<A>::construct(a, p, std::forward<U>(u)...)`.]]]]]
+[[`template<class A, class T> void alloc_construct_n(A& a, T* p,
+std::size_t n);`]
+[[variablelist
+[[Requires][`A` is an _Allocator_]]
+[[Effects]
+[Constructs each element in order by calling
+`std::allocator_traits<A>::construct(a, &p[i])`.]]
+[[Remarks]
+[If an exception is thrown, destroys each element in reverse order by
+calling `std::allocator_traits<A>::destroy(a, &p[i])`.]]]]]
+[[`template<class A, class T> void alloc_construct_n(A& a, T* p, std::size_t n,
+const T* l, std::size_t m);`]
+[[variablelist
+[[Requires][`A` is an _Allocator_]]
+[[Effects]
+[Constructs each element in order by calling
+`std::allocator_traits<A>::construct(a, &p[i], l[i % m])`.]]
+[[Remarks]
+[If an exception is thrown, destroys each element in reverse order by
+calling `std::allocator_traits<A>::destroy(a, &p[i])`.]]]]]]
+
+[endsect]
+
+[endsect]
+
+[section Acknowledgments]
+
+Glen Fernandes originally implemented this functionality in Boost.Smart_ptr and
+later moved these functions to Boost.Core for use in multiple Boost libraries.
+
+[endsect]
+
+[endsect]

doc/core.qbk

@@ -39,6 +39,7 @@ criteria for inclusion is that the utility component be:
 [endsect]
 
 [include addressof.qbk]
+[include alloc_construct.qbk]
 [include checked_delete.qbk]
 [include default_allocator.qbk]
 [include demangle.qbk]

include/boost/core/alloc_construct.hpp

@@ -0,0 +1,209 @@
+/*
+Copyright 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_CORE_ALLOC_CONSTRUCT_HPP
+#define BOOST_CORE_ALLOC_CONSTRUCT_HPP
+
+#include <boost/core/noinit_adaptor.hpp>
+
+namespace boost {
+
+#if !defined(BOOST_NO_CXX11_ALLOCATOR)
+template<class A, class T>
+inline void
+alloc_destroy(A& a, T* p)
+{
+    std::allocator_traits<A>::destroy(a, p);
+}
+
+template<class A, class T>
+inline void
+alloc_destroy_n(A& a, T* p, std::size_t n)
+{
+    while (n > 0) {
+        std::allocator_traits<A>::destroy(a, p + --n);
+    }
+}
+#else
+template<class A, class T>
+inline void
+alloc_destroy(A&, T* p)
+{
+    p->~T();
+}
+
+template<class A, class T>
+inline void
+alloc_destroy_n(A&, T* p, std::size_t n)
+{
+    while (n > 0) {
+        p[--n].~T();
+    }
+}
+#endif
+
+namespace detail {
+
+template<class A, class T>
+class alloc_destroyer {
+public:
+    alloc_destroyer(A& a, T* p) BOOST_NOEXCEPT
+        : a_(a),
+          p_(p),
+          n_(0) { }
+
+    ~alloc_destroyer() {
+        boost::alloc_destroy_n(a_, p_, n_);
+    }
+
+    std::size_t& size() BOOST_NOEXCEPT {
+        return n_;
+    }
+
+private:
+    alloc_destroyer(const alloc_destroyer&);
+    alloc_destroyer& operator=(const alloc_destroyer&);
+
+    A& a_;
+    T* p_;
+    std::size_t n_;
+};
+
+} /* detail */
+
+#if !defined(BOOST_NO_CXX11_ALLOCATOR)
+template<class A, class T>
+inline void
+alloc_construct(A& a, T* p)
+{
+    std::allocator_traits<A>::construct(a, p);
+}
+
+#if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
+#if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES)
+template<class A, class T, class U, class... V>
+inline void
+alloc_construct(A& a, T* p, U&& u, V&&... v)
+{
+    std::allocator_traits<A>::construct(a, p, std::forward<U>(u),
+        std::forward<V>(v)...);
+}
+#else
+template<class A, class T, class U>
+inline void
+alloc_construct(A& a, T* p, U&& u)
+{
+    std::allocator_traits<A>::construct(a, p, std::forward<U>(u));
+}
+#endif
+#else
+template<class A, class T, class U>
+inline void
+alloc_construct(A& a, T* p, const U& u)
+{
+    std::allocator_traits<A>::construct(a, p, u);
+}
+#endif
+
+template<class A, class T>
+inline void
+alloc_construct_n(A& a, T* p, std::size_t n)
+{
+    detail::alloc_destroyer<A, T> hold(a, p);
+    for (std::size_t& i = hold.size(); i < n; ++i) {
+        std::allocator_traits<A>::construct(a, p + i);
+    }
+    hold.size() = 0;
+}
+
+template<class A, class T>
+inline void
+alloc_construct_n(A& a, T* p, std::size_t n, const T* l, std::size_t m)
+{
+    detail::alloc_destroyer<A, T> hold(a, p);
+    for (std::size_t& i = hold.size(); i < n; ++i) {
+        std::allocator_traits<A>::construct(a, p + i, l[i % m]);
+    }
+    hold.size() = 0;
+}
+#else
+template<class A, class T>
+inline void
+alloc_construct(A&, T* p)
+{
+    ::new(static_cast<void*>(p)) T();
+}
+
+template<class A, class T>
+inline void
+alloc_construct(noinit_adaptor<A>&, T* p)
+{
+    ::new(static_cast<void*>(p)) T;
+}
+
+#if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES)
+#if !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES)
+template<class A, class T, class U, class... V>
+inline void
+alloc_construct(A&, T* p, U&& u, V&&... v)
+{
+    ::new(static_cast<void*>(p)) T(std::forward<U>(u), std::forward<V>(v)...);
+}
+#else
+template<class A, class T, class U>
+inline void
+alloc_construct(A& a, T* p, U&& u)
+{
+    ::new(static_cast<void*>(p)) T(std::forward<U>(u));
+}
+#endif
+#else
+template<class A, class T, class U>
+inline void
+alloc_construct(A&, T* p, const U& u)
+{
+    ::new(static_cast<void*>(p)) T(u);
+}
+#endif
+
+template<class A, class T>
+inline void
+alloc_construct_n(A& a, T* p, std::size_t n)
+{
+    detail::alloc_destroyer<A, T> hold(a, p);
+    for (std::size_t& i = hold.size(); i < n; ++i) {
+        ::new(static_cast<void*>(p + i)) T();
+    }
+    hold.size() = 0;
+}
+
+template<class A, class T>
+inline void
+alloc_construct_n(noinit_adaptor<A>& a, T* p, std::size_t n)
+{
+    detail::alloc_destroyer<noinit_adaptor<A>, T> hold(a, p);
+    for (std::size_t& i = hold.size(); i < n; ++i) {
+        ::new(static_cast<void*>(p + i)) T;
+    }
+    hold.size() = 0;
+}
+
+template<class A, class T>
+inline void
+alloc_construct_n(A& a, T* p, std::size_t n, const T* l, std::size_t m)
+{
+    detail::alloc_destroyer<A, T> hold(a, p);
+    for (std::size_t& i = hold.size(); i < n; ++i) {
+        ::new(static_cast<void*>(p + i)) T(l[i % m]);
+    }
+    hold.size() = 0;
+}
+#endif
+
+} /* boost */
+
+#endif

test/Jamfile.v2

@@ -138,6 +138,9 @@ compile use_default_test.cpp ;
 
 run default_allocator_test.cpp ;
 run noinit_adaptor_test.cpp ;
+run alloc_construct_test.cpp ;
+run alloc_construct_throws_test.cpp ;
+run alloc_construct_cxx11_test.cpp ;
 
 lib lib_typeid : lib_typeid.cpp : <link>shared:<define>LIB_TYPEID_DYN_LINK=1 ;
 

test/alloc_construct_cxx11_test.cpp

@@ -0,0 +1,79 @@
+/*
+Copyright 2019 Glen Joseph Fernandes
+(glenjofe@gmail.com)
+
+Distributed under the Boost Software License, Version 1.0.
+(http://www.boost.org/LICENSE_1_0.txt)
+*/
+#include <boost/config.hpp>
+#if !defined(BOOST_NO_CXX11_ALLOCATOR)
+#include <boost/core/alloc_construct.hpp>
+#include <boost/core/lightweight_test.hpp>
+
+class type {
+public:
+    explicit type(int x)
+        : value_(x) { }
+
+    int value() const {
+        return value_;
+    }
+
+    static int count;
+
+private:
+    type(const type&);
+    type& operator=(const type&);
+
+    int value_;
+};
+
+int type::count = 0;
+
+template<class T>
+struct creator {
+    typedef T value_type;
+
+    creator() { }
+
+    template<class U>
+    creator(const creator<U>&) { }
+
+    T* allocate(std::size_t size) {
+        return static_cast<T*>(::operator new(sizeof(T) * size));
+    }
+
+    void deallocate(T* ptr, std::size_t) {
+        ::operator delete(ptr);
+    }
+
+    template<class U, class V>
+    void construct(U* ptr, const V& value) {
+        ::new(static_cast<void*>(ptr)) U(value + 1);
+        ++type::count;
+    }
+
+    template<class U>
+    void destroy(U* ptr) {
+        ptr->~U();
+        --type::count;
+    }
+};
+
+int main()
+{
+    creator<type> a;
+    type* p = a.allocate(1);
+    boost::alloc_construct(a, p, 1);
+    BOOST_TEST_EQ(type::count, 1);
+    BOOST_TEST_EQ(p->value(), 2);
+    boost::alloc_destroy(a, p);
+    BOOST_TEST_EQ(type::count, 0);
+    return boost::report_errors();
+}
+#else
+int main()
+{
+    return 0;
+}
+#endif

test/alloc_construct_test.cpp

@@ -0,0 +1,119 @@
+/*
+Copyright 2019 Glen Joseph Fernandes
+(glenjofe@gmail.com)
+
+Distributed under the Boost Software License, Version 1.0.
+(http://www.boost.org/LICENSE_1_0.txt)
+*/
+#include <boost/core/alloc_construct.hpp>
+#include <boost/core/default_allocator.hpp>
+#include <boost/core/lightweight_test.hpp>
+
+class type {
+public:
+    explicit type(int x = 0, int y = 0)
+        : value_(x + y) {
+        ++count;
+    }
+
+    type(const type& other)
+        : value_(other.value_) {
+        ++count;
+    }
+
+    ~type() {
+        --count;
+    }
+
+    int value() const {
+        return value_;
+    }
+
+    static int count;
+
+private:
+    int value_;
+};
+
+int type::count = 0;
+
+void test_construct()
+{
+    boost::default_allocator<type> a;
+    type* p = a.allocate(1);
+    boost::alloc_construct(a, p);
+    BOOST_TEST_EQ(type::count, 1);
+    BOOST_TEST_EQ(p->value(), 0);
+    boost::alloc_destroy(a, p);
+    BOOST_TEST_EQ(type::count, 0);
+    a.deallocate(p, 1);
+}
+
+void test_construct_value()
+{
+    boost::default_allocator<type> a;
+    type* p = a.allocate(1);
+    boost::alloc_construct(a, p, 1);
+    BOOST_TEST_EQ(type::count, 1);
+    BOOST_TEST_EQ(p->value(), 1);
+    boost::alloc_destroy(a, p);
+    BOOST_TEST_EQ(type::count, 0);
+    a.deallocate(p, 1);
+}
+
+#if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES) && \
+    !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES)
+void test_construct_args()
+{
+    boost::default_allocator<type> a;
+    type* p = a.allocate(1);
+    boost::alloc_construct(a, p, 1, 2);
+    BOOST_TEST_EQ(type::count, 1);
+    BOOST_TEST_EQ(p->value(), 3);
+    boost::alloc_destroy(a, p);
+    BOOST_TEST_EQ(type::count, 0);
+    a.deallocate(p, 1);
+}
+#endif
+
+void test_construct_n()
+{
+    boost::default_allocator<type> a;
+    type* p = a.allocate(3);
+    boost::alloc_construct_n(a, p, 3);
+    BOOST_TEST_EQ(type::count, 3);
+    BOOST_TEST_EQ(p[0].value(), 0);
+    BOOST_TEST_EQ(p[1].value(), 0);
+    BOOST_TEST_EQ(p[2].value(), 0);
+    boost::alloc_destroy_n(a, p, 3);
+    BOOST_TEST_EQ(type::count, 0);
+    a.deallocate(p, 3);
+}
+
+void test_construct_n_list()
+{
+    boost::default_allocator<type> a;
+    type* p = a.allocate(3);
+    type q(1);
+    boost::alloc_construct_n(a, p, 3, &q, 1);
+    BOOST_TEST_EQ(type::count, 4);
+    BOOST_TEST_EQ(p[0].value(), 1);
+    BOOST_TEST_EQ(p[1].value(), 1);
+    BOOST_TEST_EQ(p[2].value(), 1);
+    boost::alloc_destroy_n(a, p, 3);
+    BOOST_TEST_EQ(type::count, 1);
+    a.deallocate(p, 3);
+}
+
+int main()
+{
+    test_construct();
+    test_construct_value();
+#if !defined(BOOST_NO_CXX11_RVALUE_REFERENCES) && \
+    !defined(BOOST_NO_CXX11_VARIADIC_TEMPLATES)
+    test_construct_args();
+#endif
+    test_construct_n();
+    test_construct_n_list();
+    return boost::report_errors();
+}

test/alloc_construct_throws_test.cpp

@@ -0,0 +1,46 @@
+/*
+Copyright 2019 Glen Joseph Fernandes
+(glenjofe@gmail.com)
+
+Distributed under the Boost Software License, Version 1.0.
+(http://www.boost.org/LICENSE_1_0.txt)
+*/
+#include <boost/core/alloc_construct.hpp>
+#include <boost/core/default_allocator.hpp>
+#include <boost/core/lightweight_test.hpp>
+
+class type {
+public:
+    type() {
+        if (count == 4) {
+            throw true;
+        }
+        ++count;
+    }
+
+    ~type() {
+        --count;
+    }
+
+    static int count;
+
+private:
+    type(const type&);
+    type& operator=(const type&);
+};
+
+int type::count = 0;
+
+int main()
+{
+    boost::default_allocator<type> a;
+    type* p = a.allocate(5);
+    try {
+        boost::alloc_construct_n(a, p, 5);
+        BOOST_ERROR("construct_n did not throw");
+    } catch (...) {
+        BOOST_TEST_EQ(type::count, 0);
+    }
+    a.deallocate(p, 5);
+    return boost::report_errors();
+}