| |
| // 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 |