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/* /////////////////////////////////////////////////////////////////////////
* File: stlsoft/smartptr/shared_ptr.hpp (originally MLShrPtr.h, ::SynesisStd)
*
* Purpose: Contains the shared_ptr template class.
*
* Created: 17th June 2002
* Updated: 3rd March 2011
*
* Home: http://stlsoft.org/
*
* Copyright (c) 2002-2011, Matthew Wilson and Synesis Software
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* - Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
* - Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* - Neither the name(s) of Matthew Wilson and Synesis Software nor the names of
* any contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
* AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
* ////////////////////////////////////////////////////////////////////// */
/** \file stlsoft/smartptr/shared_ptr.hpp
*
* \brief [C++ only] Definition of the stlsoft::shared_ptr smart
* pointer class template
* (\ref group__library__smart_pointers "Smart Pointers" Library).
*/
#ifndef STLSOFT_INCL_STLSOFT_SMARTPTR_HPP_SHARED_PTR
#define STLSOFT_INCL_STLSOFT_SMARTPTR_HPP_SHARED_PTR
#ifndef STLSOFT_DOCUMENTATION_SKIP_SECTION
# define STLSOFT_VER_STLSOFT_SMARTPTR_HPP_SHARED_PTR_MAJOR 3
# define STLSOFT_VER_STLSOFT_SMARTPTR_HPP_SHARED_PTR_MINOR 3
# define STLSOFT_VER_STLSOFT_SMARTPTR_HPP_SHARED_PTR_REVISION 1
# define STLSOFT_VER_STLSOFT_SMARTPTR_HPP_SHARED_PTR_EDIT 38
#endif /* !STLSOFT_DOCUMENTATION_SKIP_SECTION */
/* /////////////////////////////////////////////////////////////////////////
* Includes
*/
#ifndef STLSOFT_INCL_STLSOFT_H_STLSOFT
# include <stlsoft/stlsoft.h>
#endif /* !STLSOFT_INCL_STLSOFT_H_STLSOFT */
#ifndef STLSOFT_INCL_STLSOFT_UTIL_HPP_STD_SWAP
# include <stlsoft/util/std_swap.hpp>
#endif /* !STLSOFT_INCL_STLSOFT_UTIL_HPP_STD_SWAP */
/* /////////////////////////////////////////////////////////////////////////
* Namespace
*/
#ifndef _STLSOFT_NO_NAMESPACE
namespace stlsoft
{
#endif /* _STLSOFT_NO_NAMESPACE */
/* /////////////////////////////////////////////////////////////////////////
* Classes
*/
/** \brief This class enables sharing of arbitrary types.
*
* \ingroup group__library__smart_pointers
*
* \remarks The functionality is based in concept on the Boost shared_ptr,
* which is set for inclusion in the next instalment of the C++ standard.
* The implementation is entirely original.
*
* \param T The value type
*/
template <ss_typename_param_k T>
class shared_ptr
{
/// \name Types
/// @{
public:
typedef T value_type;
typedef value_type* pointer;
typedef value_type const* const_pointer;
typedef value_type& reference;
typedef value_type const& const_reference;
typedef shared_ptr<T> class_type;
typedef pointer resource_type;
typedef const_pointer const_resource_type;
/// @}
/// \name Construction
/// @{
public:
shared_ptr()
: m_p(NULL)
, m_pc(NULL)
{
STLSOFT_ASSERT(is_valid());
}
///
///
/// \note If exception handling is not enabled and memory cannot be
/// acquired to hold the sharing resource the object represented
/// by \c p will be deleted, and get() will return \c NULL
///
/// \exception std::bad_alloc If exception support is enabled,
/// an instance of <code>std::bad_alloc</code> will be thrown if
/// memory cannot be acquired to hold the sharing resource. In this
/// case, the object represented by \c p will be deleted
explicit shared_ptr(T* p)
: m_p(p)
, m_pc(NULL)
{
// This code prevents leaks in the following case:
//
// shared_ptr<Class> p(new Class());
//
// if the count cannot be allocated
if(NULL != p)
{
#ifdef STLSOFT_CF_EXCEPTION_SUPPORT
try
{
#endif /* STLSOFT_CF_EXCEPTION_SUPPORT */
m_pc = new long(1);
#ifdef STLSOFT_CF_EXCEPTION_SUPPORT
}
catch(std::bad_alloc&)
#else /* ? STLSOFT_CF_EXCEPTION_SUPPORT */
if(NULL == m_pc)
#endif /* STLSOFT_CF_EXCEPTION_SUPPORT */
{
delete m_p;
m_p = NULL; // benign for X; necessary for NoX
throw;
}
}
STLSOFT_ASSERT(is_valid());
}
shared_ptr(class_type const& rhs)
: m_p(rhs.m_p)
, m_pc(rhs.m_pc)
{
STLSOFT_ASSERT(rhs.is_valid());
if(NULL != m_pc)
{
++*m_pc;
}
STLSOFT_ASSERT(is_valid());
}
#if defined(STLSOFT_CF_MEMBER_TEMPLATE_FUNCTION_SUPPORT) && \
( !defined(STLSOFT_COMPILER_IS_MSVC) || \
_MSC_VER > 1200)
template <ss_typename_param_k T2>
shared_ptr(shared_ptr<T2> const& rhs)
: m_p(rhs.m_p)
, m_pc(rhs.m_pc)
{
STLSOFT_ASSERT(rhs.is_valid());
STLSOFT_ASSERT((NULL == m_p) == (NULL == m_pc));
if(NULL != m_pc)
{
++*m_pc;
}
STLSOFT_ASSERT(is_valid());
}
#endif /* member template support? */
~shared_ptr() stlsoft_throw_0()
{
STLSOFT_ASSERT(is_valid());
STLSOFT_ASSERT((NULL == m_p) == (NULL == m_pc));
STLSOFT_ASSERT((NULL == m_pc) || (0 < *m_pc));
if( NULL != m_pc &&
0 == --*m_pc)
{
delete m_p;
delete m_pc;
}
}
class_type& operator =(class_type const& rhs)
{
STLSOFT_ASSERT(is_valid());
class_type this_(rhs);
this_.swap(*this);
STLSOFT_ASSERT(is_valid());
return *this;
}
#if defined(STLSOFT_CF_MEMBER_TEMPLATE_FUNCTION_SUPPORT) && \
( !defined(STLSOFT_COMPILER_IS_MSVC) || \
_MSC_VER > 1200)
template <ss_typename_param_k T2>
class_type& operator =(shared_ptr<T2> const& rhs)
{
STLSOFT_ASSERT(rhs.is_valid());
STLSOFT_ASSERT(is_valid());
class_type this_(rhs);
this_.swap(*this);
STLSOFT_ASSERT(is_valid());
return *this;
}
#endif /* member template support? */
/// @}
/// \name Operations
/// @{
public:
void close()
{
STLSOFT_ASSERT((NULL == m_p) == (NULL == m_pc));
STLSOFT_ASSERT((NULL == m_pc) || (0 < *m_pc));
STLSOFT_ASSERT(is_valid());
if(NULL != m_pc)
{
pointer p = m_p;
long *pc = m_pc;
// Set the members to NULL prior to possibly
// deleting, in case close() is called on a
// shared_ptr member which is holding a
// reference to the enclosing instance.
m_p = NULL;
m_pc = NULL;
if(0 == --*pc)
{
delete p;
delete pc;
}
}
STLSOFT_ASSERT(is_valid());
}
#if 1 && !defined(STLSOFT_DOCUMENTATION_SKIP_SECTION)
void reset()
{
close();
}
#endif /* !STLSOFT_DOCUMENTATION_SKIP_SECTION */
pointer detach()
{
STLSOFT_ASSERT((NULL == m_p) == (NULL == m_pc));
STLSOFT_ASSERT((NULL == m_pc) || (0 < *m_pc));
STLSOFT_ASSERT(is_valid());
pointer p = NULL;
if(NULL != m_pc)
{
if(0 == --*m_pc)
{
delete m_pc;
m_pc = NULL;
}
std_swap(p, m_p);
}
STLSOFT_ASSERT(is_valid());
return p;
}
void swap(class_type& rhs)
{
STLSOFT_ASSERT(rhs.is_valid());
STLSOFT_ASSERT(is_valid());
std_swap(m_p, rhs.m_p);
std_swap(m_pc, rhs.m_pc);
STLSOFT_ASSERT(is_valid());
}
/// @}
/// \name Accessors
/// @{
public:
const_pointer operator ->() const
{
STLSOFT_ASSERT(NULL != m_p);
STLSOFT_ASSERT(is_valid());
return m_p;
}
pointer operator ->()
{
STLSOFT_ASSERT(NULL != m_p);
STLSOFT_ASSERT(is_valid());
return m_p;
}
pointer get() const
{
STLSOFT_ASSERT(is_valid());
return m_p;
}
const_reference operator *() const
{
STLSOFT_ASSERT(NULL != m_p);
STLSOFT_ASSERT(is_valid());
return *m_p;
}
reference operator *()
{
STLSOFT_ASSERT(NULL != m_p);
STLSOFT_ASSERT(is_valid());
return *m_p;
}
/// @}
/// \name Attributes
/// @{
public:
long count() const
{
STLSOFT_ASSERT(is_valid());
return (NULL == m_pc) ? 0 : *m_pc;
}
/// \brief Returns count()
long use_count() const
{
STLSOFT_ASSERT(is_valid());
return this->count();
}
/// @}
/// \name Implementation
/// @{
private:
ss_bool_t is_valid() const
{
if((NULL == m_p) != (NULL == m_pc))
{
#ifdef STLSOFT_UNITTEST
fprintf(err, "Managed object's pointer and shared count pointer must both be NULL, or both non-NULL!\n");
#endif /* STLSOFT_UNITTEST */
return false;
}
if( NULL != m_pc &&
*m_pc < 1)
{
#ifdef STLSOFT_UNITTEST
fprintf(err, "Shared count cannot be less than 1!\n");
#endif /* STLSOFT_UNITTEST */
return false;
}
return true;
}
/// @}
/// \name Members
/// @{
private:
pointer m_p;
long *m_pc;
/// @}
};
/* /////////////////////////////////////////////////////////////////////////
* swapping
*/
template <ss_typename_param_k T>
void swap(shared_ptr<T>& lhs, shared_ptr<T>& rhs)
{
lhs.swap(rhs);
}
/* /////////////////////////////////////////////////////////////////////////
* Shims
*/
#if !defined(STLSOFT_COMPILER_IS_WATCOM)
/** \brief get_ptr shim
*
* \ingroup group__library__smart_pointers
*/
template<ss_typename_param_k T>
inline T* get_ptr(shared_ptr<T> const& p)
{
return p.get();
}
/** \brief Insertion operator shim
*
* \ingroup group__library__smart_pointers
*/
template< ss_typename_param_k S
, ss_typename_param_k T
>
inline S& operator <<(S& s, shared_ptr<T> const& p)
{
return s << *p;
}
#endif /* compiler */
/* ////////////////////////////////////////////////////////////////////// */
#ifndef _STLSOFT_NO_NAMESPACE
} // namespace stlsoft
#endif /* _STLSOFT_NO_NAMESPACE */
/* In the special case of Intel behaving as VC++ 7.0 or earlier on Win32, we
* illegally insert into the std namespace.
*/
#if defined(STLSOFT_CF_std_NAMESPACE)
# if ( ( defined(STLSOFT_COMPILER_IS_INTEL) && \
defined(_MSC_VER))) && \
_MSC_VER < 1310
namespace std
{
template< ss_typename_param_k T
>
inline void swap(stlsoft_ns_qual(shared_ptr)<T>& lhs, stlsoft_ns_qual(shared_ptr)<T>& rhs)
{
lhs.swap(rhs);
}
} // namespace std
# endif /* INTEL && _MSC_VER < 1310 */
#endif /* STLSOFT_CF_std_NAMESPACE */
/* ////////////////////////////////////////////////////////////////////// */
#endif /* !STLSOFT_INCL_STLSOFT_SMARTPTR_HPP_SHARED_PTR */
/* ///////////////////////////// end of file //////////////////////////// */