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author | Henrik Edin <henrik.edin@mongodb.com> | 2018-12-13 11:44:21 -0500 |
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committer | Henrik Edin <henrik.edin@mongodb.com> | 2018-12-18 09:12:51 -0500 |
commit | c28cb6852fca219d6f0262000c378e982b7ca9ff (patch) | |
tree | e06e74d1729e644db7c4dc2e5ecd529145b2f34c /src/third_party/boost-1.69.0/boost/smart_ptr/detail/sp_counted_base_clang.hpp | |
parent | 05ebfef11161b96ba0e8374f34c359a403097f60 (diff) | |
download | mongo-c28cb6852fca219d6f0262000c378e982b7ca9ff.tar.gz |
SERVER-38458 Upgrade boost to version 1.69
Diffstat (limited to 'src/third_party/boost-1.69.0/boost/smart_ptr/detail/sp_counted_base_clang.hpp')
-rw-r--r-- | src/third_party/boost-1.69.0/boost/smart_ptr/detail/sp_counted_base_clang.hpp | 151 |
1 files changed, 151 insertions, 0 deletions
diff --git a/src/third_party/boost-1.69.0/boost/smart_ptr/detail/sp_counted_base_clang.hpp b/src/third_party/boost-1.69.0/boost/smart_ptr/detail/sp_counted_base_clang.hpp new file mode 100644 index 00000000000..c2c20d3ab9f --- /dev/null +++ b/src/third_party/boost-1.69.0/boost/smart_ptr/detail/sp_counted_base_clang.hpp @@ -0,0 +1,151 @@ +#ifndef BOOST_SMART_PTR_DETAIL_SP_COUNTED_BASE_CLANG_HPP_INCLUDED +#define BOOST_SMART_PTR_DETAIL_SP_COUNTED_BASE_CLANG_HPP_INCLUDED + +// MS compatible compilers support #pragma once + +#if defined(_MSC_VER) && (_MSC_VER >= 1020) +# pragma once +#endif + +// detail/sp_counted_base_clang.hpp - __c11 clang intrinsics +// +// Copyright (c) 2007, 2013, 2015 Peter Dimov +// +// Distributed under the Boost Software License, Version 1.0. +// See accompanying file LICENSE_1_0.txt or copy at +// http://www.boost.org/LICENSE_1_0.txt + +#include <boost/detail/sp_typeinfo.hpp> +#include <boost/config.hpp> +#include <boost/cstdint.hpp> + +namespace boost +{ + +namespace detail +{ + +typedef _Atomic( boost::int_least32_t ) atomic_int_least32_t; + +inline void atomic_increment( atomic_int_least32_t * pw ) +{ + __c11_atomic_fetch_add( pw, 1, __ATOMIC_RELAXED ); +} + +inline boost::int_least32_t atomic_decrement( atomic_int_least32_t * pw ) +{ + return __c11_atomic_fetch_sub( pw, 1, __ATOMIC_ACQ_REL ); +} + +inline boost::int_least32_t atomic_conditional_increment( atomic_int_least32_t * pw ) +{ + // long r = *pw; + // if( r != 0 ) ++*pw; + // return r; + + boost::int_least32_t r = __c11_atomic_load( pw, __ATOMIC_RELAXED ); + + for( ;; ) + { + if( r == 0 ) + { + return r; + } + + if( __c11_atomic_compare_exchange_weak( pw, &r, r + 1, __ATOMIC_RELAXED, __ATOMIC_RELAXED ) ) + { + return r; + } + } +} + +#if defined(__clang__) +# pragma clang diagnostic push +# pragma clang diagnostic ignored "-Wweak-vtables" +#endif + +class BOOST_SYMBOL_VISIBLE sp_counted_base +{ +private: + + sp_counted_base( sp_counted_base const & ); + sp_counted_base & operator= ( sp_counted_base const & ); + + atomic_int_least32_t use_count_; // #shared + atomic_int_least32_t weak_count_; // #weak + (#shared != 0) + +public: + + sp_counted_base() + { + __c11_atomic_init( &use_count_, 1 ); + __c11_atomic_init( &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 + + // destroy() is called when weak_count_ drops to zero. + + virtual void destroy() // nothrow + { + delete this; + } + + virtual void * get_deleter( sp_typeinfo const & ti ) = 0; + virtual void * get_local_deleter( sp_typeinfo const & ti ) = 0; + virtual void * get_untyped_deleter() = 0; + + void add_ref_copy() + { + atomic_increment( &use_count_ ); + } + + bool add_ref_lock() // true on success + { + return atomic_conditional_increment( &use_count_ ) != 0; + } + + void release() // nothrow + { + if( atomic_decrement( &use_count_ ) == 1 ) + { + dispose(); + weak_release(); + } + } + + void weak_add_ref() // nothrow + { + atomic_increment( &weak_count_ ); + } + + void weak_release() // nothrow + { + if( atomic_decrement( &weak_count_ ) == 1 ) + { + destroy(); + } + } + + long use_count() const // nothrow + { + return __c11_atomic_load( const_cast< atomic_int_least32_t* >( &use_count_ ), __ATOMIC_ACQUIRE ); + } +}; + +#if defined(__clang__) +# pragma clang diagnostic pop +#endif + +} // namespace detail + +} // namespace boost + +#endif // #ifndef BOOST_SMART_PTR_DETAIL_SP_COUNTED_BASE_CLANG_HPP_INCLUDED |