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Diffstat (limited to 'src/boost/detail/shared_count.hpp')
| -rw-r--r-- | src/boost/detail/shared_count.hpp | 555 |
1 files changed, 555 insertions, 0 deletions
diff --git a/src/boost/detail/shared_count.hpp b/src/boost/detail/shared_count.hpp new file mode 100644 index 000000000000..23e78413f721 --- /dev/null +++ b/src/boost/detail/shared_count.hpp @@ -0,0 +1,555 @@ +#ifndef BOOST_DETAIL_SHARED_COUNT_HPP_INCLUDED +#define BOOST_DETAIL_SHARED_COUNT_HPP_INCLUDED + +// MS compatible compilers support #pragma once + +#if defined(_MSC_VER) && (_MSC_VER >= 1020) +# pragma once +#endif + +// +// detail/shared_count.hpp +// +// Copyright (c) 2001, 2002, 2003 Peter Dimov and Multi Media Ltd. +// +// Permission to copy, use, modify, sell and distribute this software +// is granted provided this copyright notice appears in all copies. +// This software is provided "as is" without express or implied +// warranty, and with no claim as to its suitability for any purpose. +// + +//#include <boost/config.hpp> + +#if defined(BOOST_SP_USE_STD_ALLOCATOR) && defined(BOOST_SP_USE_QUICK_ALLOCATOR) +# error BOOST_SP_USE_STD_ALLOCATOR and BOOST_SP_USE_QUICK_ALLOCATOR are incompatible. +#endif + +#include <boost/checked_delete.hpp> +#include <boost/throw_exception.hpp> +//#include <boost/detail/lightweight_mutex.hpp> + +#if defined(BOOST_SP_USE_QUICK_ALLOCATOR) +#include <boost/detail/quick_allocator.hpp> +#endif + +#include <memory> // std::auto_ptr, std::allocator +#include <functional> // std::less +#include <exception> // std::exception +#include <new> // std::bad_alloc +#include <typeinfo> // std::type_info in get_deleter +#include <cstddef> // std::size_t + +#ifdef __BORLANDC__ +# pragma warn -8026 // Functions with excep. spec. are not expanded inline +# pragma warn -8027 // Functions containing try are not expanded inline +#endif + +namespace boost +{ + +// Debug hooks + +#if defined(BOOST_SP_ENABLE_DEBUG_HOOKS) + +void sp_scalar_constructor_hook(void * px, std::size_t size, void * pn); +void sp_array_constructor_hook(void * px); +void sp_scalar_destructor_hook(void * px, std::size_t size, void * pn); +void sp_array_destructor_hook(void * px); + +#endif + + +// The standard library that comes with Borland C++ 5.5.1 +// defines std::exception and its members as having C calling +// convention (-pc). When the definition of bad_weak_ptr +// is compiled with -ps, the compiler issues an error. +// Hence, the temporary #pragma option -pc below. The version +// check is deliberately conservative. + +#if defined(__BORLANDC__) && __BORLANDC__ == 0x551 +# pragma option push -pc +#endif + +class bad_weak_ptr: public std::exception +{ +public: + + virtual char const * what() const throw() + { + return "boost::bad_weak_ptr"; + } +}; + +#if defined(__BORLANDC__) && __BORLANDC__ == 0x551 +# pragma option pop +#endif + +namespace detail +{ + +class sp_counted_base +{ +private: + + // typedef detail::lightweight_mutex mutex_type; + +public: + + sp_counted_base(): use_count_(1), weak_count_(1) + { + } + + virtual ~sp_counted_base() // nothrow + { + } + + // dispose() is called when use_count_ drops to zero, to release + // the resources managed by *this. + + virtual void dispose() = 0; // nothrow + + // destruct() is called when weak_count_ drops to zero. + + virtual void destruct() // nothrow + { + delete this; + } + + virtual void * get_deleter(std::type_info const & ti) = 0; + + void add_ref_copy() + { +#if defined(BOOST_HAS_THREADS) + mutex_type::scoped_lock lock(mtx_); +#endif + ++use_count_; + } + + void add_ref_lock() + { +#if defined(BOOST_HAS_THREADS) + mutex_type::scoped_lock lock(mtx_); +#endif + if(use_count_ == 0) boost::throw_exception(boost::bad_weak_ptr()); + ++use_count_; + } + + void release() // nothrow + { + { +#if defined(BOOST_HAS_THREADS) + mutex_type::scoped_lock lock(mtx_); +#endif + long new_use_count = --use_count_; + + if(new_use_count != 0) return; + } + + dispose(); + weak_release(); + } + + void weak_add_ref() // nothrow + { +#if defined(BOOST_HAS_THREADS) + mutex_type::scoped_lock lock(mtx_); +#endif + ++weak_count_; + } + + void weak_release() // nothrow + { + long new_weak_count; + + { +#if defined(BOOST_HAS_THREADS) + mutex_type::scoped_lock lock(mtx_); +#endif + new_weak_count = --weak_count_; + } + + if(new_weak_count == 0) + { + destruct(); + } + } + + long use_count() const // nothrow + { +#if defined(BOOST_HAS_THREADS) + mutex_type::scoped_lock lock(mtx_); +#endif + return use_count_; + } + +private: + + sp_counted_base(sp_counted_base const &); + sp_counted_base & operator= (sp_counted_base const &); + + long use_count_; // #shared + long weak_count_; // #weak + (#shared != 0) + +#if defined(BOOST_HAS_THREADS) || defined(BOOST_LWM_WIN32) + mutable mutex_type mtx_; +#endif +}; + +#if defined(BOOST_SP_ENABLE_DEBUG_HOOKS) + +template<class T> void cbi_call_constructor_hook(sp_counted_base * pn, T * px, checked_deleter<T> const &, int) +{ + boost::sp_scalar_constructor_hook(px, sizeof(T), pn); +} + +template<class T> void cbi_call_constructor_hook(sp_counted_base *, T * px, checked_array_deleter<T> const &, int) +{ + boost::sp_array_constructor_hook(px); +} + +template<class P, class D> void cbi_call_constructor_hook(sp_counted_base *, P const &, D const &, long) +{ +} + +template<class T> void cbi_call_destructor_hook(sp_counted_base * pn, T * px, checked_deleter<T> const &, int) +{ + boost::sp_scalar_destructor_hook(px, sizeof(T), pn); +} + +template<class T> void cbi_call_destructor_hook(sp_counted_base *, T * px, checked_array_deleter<T> const &, int) +{ + boost::sp_array_destructor_hook(px); +} + +template<class P, class D> void cbi_call_destructor_hook(sp_counted_base *, P const &, D const &, long) +{ +} + +#endif + +// +// Borland's Codeguard trips up over the -Vx- option here: +// +#ifdef __CODEGUARD__ +# pragma option push -Vx- +#endif + +template<class P, class D> class sp_counted_base_impl: public sp_counted_base +{ +private: + + P ptr; // copy constructor must not throw + D del; // copy constructor must not throw + + sp_counted_base_impl(sp_counted_base_impl const &); + sp_counted_base_impl & operator= (sp_counted_base_impl const &); + + typedef sp_counted_base_impl<P, D> this_type; + +public: + + // pre: initial_use_count <= initial_weak_count, d(p) must not throw + + sp_counted_base_impl(P p, D d): ptr(p), del(d) + { +#if defined(BOOST_SP_ENABLE_DEBUG_HOOKS) + detail::cbi_call_constructor_hook(this, p, d, 0); +#endif + } + + virtual void dispose() // nothrow + { +#if defined(BOOST_SP_ENABLE_DEBUG_HOOKS) + detail::cbi_call_destructor_hook(this, ptr, del, 0); +#endif + del(ptr); + } + + virtual void * get_deleter(std::type_info const & ti) + { + return ti == typeid(D)? &del: 0; + } + +#if defined(BOOST_SP_USE_STD_ALLOCATOR) + + void * operator new(std::size_t) + { + return std::allocator<this_type>().allocate(1, static_cast<this_type *>(0)); + } + + void operator delete(void * p) + { + std::allocator<this_type>().deallocate(static_cast<this_type *>(p), 1); + } + +#endif + +#if defined(BOOST_SP_USE_QUICK_ALLOCATOR) + + void * operator new(std::size_t) + { + return quick_allocator<this_type>::alloc(); + } + + void operator delete(void * p) + { + quick_allocator<this_type>::dealloc(p); + } + +#endif +}; + +#if defined(BOOST_SP_ENABLE_DEBUG_HOOKS) + +int const shared_count_id = 0x2C35F101; +int const weak_count_id = 0x298C38A4; + +#endif + +class weak_count; + +class shared_count +{ +private: + + sp_counted_base * pi_; + +#if defined(BOOST_SP_ENABLE_DEBUG_HOOKS) + int id_; +#endif + + friend class weak_count; + +public: + + shared_count(): pi_(0) // nothrow +#if defined(BOOST_SP_ENABLE_DEBUG_HOOKS) + , id_(shared_count_id) +#endif + { + } + + template<class P, class D> shared_count(P p, D d): pi_(0) +#if defined(BOOST_SP_ENABLE_DEBUG_HOOKS) + , id_(shared_count_id) +#endif + { +#ifndef BOOST_NO_EXCEPTIONS + + try + { + pi_ = new sp_counted_base_impl<P, D>(p, d); + } + catch(...) + { + d(p); // delete p + throw; + } + +#else + + pi_ = new sp_counted_base_impl<P, D>(p, d); + + if(pi_ == 0) + { + d(p); // delete p + boost::throw_exception(std::bad_alloc()); + } + +#endif + } + +#ifndef BOOST_NO_AUTO_PTR + + // auto_ptr<Y> is special cased to provide the strong guarantee + + template<class Y> + explicit shared_count(std::auto_ptr<Y> & r): pi_(new sp_counted_base_impl< Y *, checked_deleter<Y> >(r.get(), checked_deleter<Y>())) +#if defined(BOOST_SP_ENABLE_DEBUG_HOOKS) + , id_(shared_count_id) +#endif + { + r.release(); + } + +#endif + + ~shared_count() // nothrow + { + if(pi_ != 0) pi_->release(); +#if defined(BOOST_SP_ENABLE_DEBUG_HOOKS) + id_ = 0; +#endif + } + + shared_count(shared_count const & r): pi_(r.pi_) // nothrow +#if defined(BOOST_SP_ENABLE_DEBUG_HOOKS) + , id_(shared_count_id) +#endif + { + if(pi_ != 0) pi_->add_ref_copy(); + } + + explicit shared_count(weak_count const & r); // throws bad_weak_ptr when r.use_count() == 0 + + shared_count & operator= (shared_count const & r) // nothrow + { + sp_counted_base * tmp = r.pi_; + if(tmp != 0) tmp->add_ref_copy(); + if(pi_ != 0) pi_->release(); + pi_ = tmp; + + return *this; + } + + void swap(shared_count & r) // nothrow + { + sp_counted_base * tmp = r.pi_; + r.pi_ = pi_; + pi_ = tmp; + } + + long use_count() const // nothrow + { + return pi_ != 0? pi_->use_count(): 0; + } + + bool unique() const // nothrow + { + return use_count() == 1; + } + + friend inline bool operator==(shared_count const & a, shared_count const & b) + { + return a.pi_ == b.pi_; + } + + friend inline bool operator<(shared_count const & a, shared_count const & b) + { + return std::less<sp_counted_base *>()(a.pi_, b.pi_); + } + + void * get_deleter(std::type_info const & ti) const + { + return pi_? pi_->get_deleter(ti): 0; + } +}; + +#ifdef __CODEGUARD__ +# pragma option pop +#endif + + +class weak_count +{ +private: + + sp_counted_base * pi_; + +#if defined(BOOST_SP_ENABLE_DEBUG_HOOKS) + int id_; +#endif + + friend class shared_count; + +public: + + weak_count(): pi_(0) // nothrow +#if defined(BOOST_SP_ENABLE_DEBUG_HOOKS) + , id_(weak_count_id) +#endif + { + } + + weak_count(shared_count const & r): pi_(r.pi_) // nothrow +#if defined(BOOST_SP_ENABLE_DEBUG_HOOKS) + , id_(shared_count_id) +#endif + { + if(pi_ != 0) pi_->weak_add_ref(); + } + + weak_count(weak_count const & r): pi_(r.pi_) // nothrow +#if defined(BOOST_SP_ENABLE_DEBUG_HOOKS) + , id_(shared_count_id) +#endif + { + if(pi_ != 0) pi_->weak_add_ref(); + } + + ~weak_count() // nothrow + { + if(pi_ != 0) pi_->weak_release(); +#if defined(BOOST_SP_ENABLE_DEBUG_HOOKS) + id_ = 0; +#endif + } + + weak_count & operator= (shared_count const & r) // nothrow + { + sp_counted_base * tmp = r.pi_; + if(tmp != 0) tmp->weak_add_ref(); + if(pi_ != 0) pi_->weak_release(); + pi_ = tmp; + + return *this; + } + + weak_count & operator= (weak_count const & r) // nothrow + { + sp_counted_base * tmp = r.pi_; + if(tmp != 0) tmp->weak_add_ref(); + if(pi_ != 0) pi_->weak_release(); + pi_ = tmp; + + return *this; + } + + void swap(weak_count & r) // nothrow + { + sp_counted_base * tmp = r.pi_; + r.pi_ = pi_; + pi_ = tmp; + } + + long use_count() const // nothrow + { + return pi_ != 0? pi_->use_count(): 0; + } + + friend inline bool operator==(weak_count const & a, weak_count const & b) + { + return a.pi_ == b.pi_; + } + + friend inline bool operator<(weak_count const & a, weak_count const & b) + { + return std::less<sp_counted_base *>()(a.pi_, b.pi_); + } +}; + +inline shared_count::shared_count(weak_count const & r): pi_(r.pi_) +#if defined(BOOST_SP_ENABLE_DEBUG_HOOKS) + , id_(shared_count_id) +#endif +{ + if(pi_ != 0) + { + pi_->add_ref_lock(); + } + else + { + boost::throw_exception(boost::bad_weak_ptr()); + } +} + +} // namespace detail + +} // namespace boost + +#ifdef __BORLANDC__ +# pragma warn .8027 // Functions containing try are not expanded inline +# pragma warn .8026 // Functions with excep. spec. are not expanded inline +#endif + +#endif // #ifndef BOOST_DETAIL_SHARED_COUNT_HPP_INCLUDED |