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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 //////////////////////////// */
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