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Diffstat (limited to 'src/third_party/boost-1.69.0/boost/coroutine/windows/protected_stack_allocator.hpp')
-rw-r--r-- | src/third_party/boost-1.69.0/boost/coroutine/windows/protected_stack_allocator.hpp | 87 |
1 files changed, 87 insertions, 0 deletions
diff --git a/src/third_party/boost-1.69.0/boost/coroutine/windows/protected_stack_allocator.hpp b/src/third_party/boost-1.69.0/boost/coroutine/windows/protected_stack_allocator.hpp new file mode 100644 index 00000000000..29e19babb7e --- /dev/null +++ b/src/third_party/boost-1.69.0/boost/coroutine/windows/protected_stack_allocator.hpp @@ -0,0 +1,87 @@ + +// Copyright Oliver Kowalke 2009. +// 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) + +#ifndef BOOST_COROUTINES_PROTECTED_STACK_ALLOCATOR_H +#define BOOST_COROUTINES_PROTECTED_STACK_ALLOCATOR_H + +extern "C" { +#include <windows.h> +} + +#include <cmath> +#include <cstddef> +#include <new> + +#include <boost/config.hpp> + +#include <boost/coroutine/detail/config.hpp> +#include <boost/coroutine/stack_traits.hpp> + +#ifdef BOOST_HAS_ABI_HEADERS +# include BOOST_ABI_PREFIX +#endif + +namespace boost { +namespace coroutines { + +struct stack_context; + +template< typename traitsT > +struct basic_protected_stack_allocator +{ + typedef traitsT traits_type; + + void allocate( stack_context & ctx, std::size_t size) + { + BOOST_ASSERT( traits_type::minimum_size() <= size); + BOOST_ASSERT( traits_type::is_unbounded() || ( traits_type::maximum_size() >= size) ); + + // page at bottom will be used as guard-page + const std::size_t pages( + static_cast< std::size_t >( + std::floor( + static_cast< float >( size) / traits_type::page_size() ) ) ); + BOOST_ASSERT_MSG( 2 <= pages, "at least two pages must fit into stack (one page is guard-page)"); + const std::size_t size_ = pages * traits_type::page_size(); + BOOST_ASSERT( 0 != size && 0 != size_); + + void * limit = ::VirtualAlloc( 0, size_, MEM_COMMIT, PAGE_READWRITE); + if ( ! limit) throw std::bad_alloc(); + + DWORD old_options; +#if defined(BOOST_DISABLE_ASSERTS) + ::VirtualProtect( + limit, traits_type::page_size(), PAGE_READWRITE | PAGE_GUARD /*PAGE_NOACCESS*/, & old_options); +#else + const BOOL result = ::VirtualProtect( + limit, traits_type::page_size(), PAGE_READWRITE | PAGE_GUARD /*PAGE_NOACCESS*/, & old_options); + BOOST_ASSERT( FALSE != result); +#endif + + ctx.size = size_; + ctx.sp = static_cast< char * >( limit) + ctx.size; + } + + void deallocate( stack_context & ctx) + { + BOOST_ASSERT( ctx.sp); + BOOST_ASSERT( traits_type::minimum_size() <= ctx.size); + BOOST_ASSERT( traits_type::is_unbounded() || ( traits_type::maximum_size() >= ctx.size) ); + + void * limit = static_cast< char * >( ctx.sp) - ctx.size; + ::VirtualFree( limit, 0, MEM_RELEASE); + } +}; + +typedef basic_protected_stack_allocator< stack_traits > protected_stack_allocator; + +}} + +#ifdef BOOST_HAS_ABI_HEADERS +# include BOOST_ABI_SUFFIX +#endif + +#endif // BOOST_COROUTINES_PROTECTED_STACK_ALLOCATOR_H |