williamr@2: #ifndef BOOST_DETAIL_SHARED_ARRAY_NMT_HPP_INCLUDED
williamr@2: #define BOOST_DETAIL_SHARED_ARRAY_NMT_HPP_INCLUDED
williamr@2: 
williamr@2: //
williamr@2: //  detail/shared_array_nmt.hpp - shared_array.hpp without member templates
williamr@2: //
williamr@2: //  (C) Copyright Greg Colvin and Beman Dawes 1998, 1999.
williamr@2: //  Copyright (c) 2001, 2002 Peter Dimov
williamr@2: //
williamr@2: //  Distributed under the Boost Software License, Version 1.0. (See
williamr@2: //  accompanying file LICENSE_1_0.txt or copy at
williamr@2: //  http://www.boost.org/LICENSE_1_0.txt)
williamr@2: //
williamr@2: //  See http://www.boost.org/libs/smart_ptr/shared_array.htm for documentation.
williamr@2: //
williamr@2: 
williamr@2: #include <boost/assert.hpp>
williamr@2: #include <boost/checked_delete.hpp>
williamr@2: #include <boost/throw_exception.hpp>
williamr@2: #include <boost/detail/atomic_count.hpp>
williamr@2: 
williamr@2: #include <cstddef>          // for std::ptrdiff_t
williamr@2: #include <algorithm>        // for std::swap
williamr@2: #include <functional>       // for std::less
williamr@2: #include <new>              // for std::bad_alloc
williamr@2: 
williamr@2: namespace boost
williamr@2: {
williamr@2: 
williamr@2: template<class T> class shared_array
williamr@2: {
williamr@2: private:
williamr@2: 
williamr@2:     typedef detail::atomic_count count_type;
williamr@2: 
williamr@2: public:
williamr@2: 
williamr@2:     typedef T element_type;
williamr@2:       
williamr@2:     explicit shared_array(T * p = 0): px(p)
williamr@2:     {
williamr@2: #ifndef BOOST_NO_EXCEPTIONS
williamr@2: 
williamr@2:         try  // prevent leak if new throws
williamr@2:         {
williamr@2:             pn = new count_type(1);
williamr@2:         }
williamr@2:         catch(...)
williamr@2:         {
williamr@2:             boost::checked_array_delete(p);
williamr@2:             throw;
williamr@2:         }
williamr@2: 
williamr@2: #else
williamr@2: 
williamr@2:         pn = new count_type(1);
williamr@2: 
williamr@2:         if(pn == 0)
williamr@2:         {
williamr@2:             boost::checked_array_delete(p);
williamr@2:             boost::throw_exception(std::bad_alloc());
williamr@2:         }
williamr@2: 
williamr@2: #endif
williamr@2:     }
williamr@2: 
williamr@2:     ~shared_array()
williamr@2:     {
williamr@2:         if(--*pn == 0)
williamr@2:         {
williamr@2:             boost::checked_array_delete(px);
williamr@2:             delete pn;
williamr@2:         }
williamr@2:     }
williamr@2: 
williamr@2:     shared_array(shared_array const & r) : px(r.px)  // never throws
williamr@2:     {
williamr@2:         pn = r.pn;
williamr@2:         ++*pn;
williamr@2:     }
williamr@2: 
williamr@2:     shared_array & operator=(shared_array const & r)
williamr@2:     {
williamr@2:         shared_array(r).swap(*this);
williamr@2:         return *this;
williamr@2:     }
williamr@2: 
williamr@2:     void reset(T * p = 0)
williamr@2:     {
williamr@2:         BOOST_ASSERT(p == 0 || p != px);
williamr@2:         shared_array(p).swap(*this);
williamr@2:     }
williamr@2: 
williamr@2:     T * get() const  // never throws
williamr@2:     {
williamr@2:         return px;
williamr@2:     }
williamr@2: 
williamr@2:     T & operator[](std::ptrdiff_t i) const  // never throws
williamr@2:     {
williamr@2:         BOOST_ASSERT(px != 0);
williamr@2:         BOOST_ASSERT(i >= 0);
williamr@2:         return px[i];
williamr@2:     }
williamr@2: 
williamr@2:     long use_count() const  // never throws
williamr@2:     {
williamr@2:         return *pn;
williamr@2:     }
williamr@2: 
williamr@2:     bool unique() const  // never throws
williamr@2:     {
williamr@2:         return *pn == 1;
williamr@2:     }
williamr@2: 
williamr@2:     void swap(shared_array<T> & other)  // never throws
williamr@2:     {
williamr@2:         std::swap(px, other.px);
williamr@2:         std::swap(pn, other.pn);
williamr@2:     }
williamr@2: 
williamr@2: private:
williamr@2: 
williamr@2:     T * px;            // contained pointer
williamr@2:     count_type * pn;   // ptr to reference counter
williamr@2:       
williamr@2: };  // shared_array
williamr@2: 
williamr@2: template<class T, class U> inline bool operator==(shared_array<T> const & a, shared_array<U> const & b)
williamr@2: {
williamr@2:     return a.get() == b.get();
williamr@2: }
williamr@2: 
williamr@2: template<class T, class U> inline bool operator!=(shared_array<T> const & a, shared_array<U> const & b)
williamr@2: {
williamr@2:     return a.get() != b.get();
williamr@2: }
williamr@2: 
williamr@2: template<class T> inline bool operator<(shared_array<T> const & a, shared_array<T> const & b)
williamr@2: {
williamr@2:     return std::less<T*>()(a.get(), b.get());
williamr@2: }
williamr@2: 
williamr@2: template<class T> void swap(shared_array<T> & a, shared_array<T> & b)
williamr@2: {
williamr@2:     a.swap(b);
williamr@2: }
williamr@2: 
williamr@2: } // namespace boost
williamr@2: 
williamr@2: #endif  // #ifndef BOOST_DETAIL_SHARED_ARRAY_NMT_HPP_INCLUDED