459 lines
14 KiB
C++
Executable File
459 lines
14 KiB
C++
Executable File
|
|
// Copyright Oliver Kowalke 2017.
|
|
// 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_CONTEXT_FIBER_H
|
|
#define BOOST_CONTEXT_FIBER_H
|
|
|
|
#include <windows.h>
|
|
|
|
#include <boost/context/detail/config.hpp>
|
|
|
|
#include <algorithm>
|
|
#include <cstddef>
|
|
#include <cstdint>
|
|
#include <cstdlib>
|
|
#include <cstring>
|
|
#include <functional>
|
|
#include <memory>
|
|
#include <ostream>
|
|
#include <system_error>
|
|
#include <tuple>
|
|
#include <utility>
|
|
|
|
#include <boost/assert.hpp>
|
|
#include <boost/config.hpp>
|
|
|
|
#include <boost/context/detail/disable_overload.hpp>
|
|
#if defined(BOOST_NO_CXX14_STD_EXCHANGE)
|
|
#include <boost/context/detail/exchange.hpp>
|
|
#endif
|
|
#if defined(BOOST_NO_CXX17_STD_INVOKE)
|
|
#include <boost/context/detail/invoke.hpp>
|
|
#endif
|
|
#include <boost/context/fixedsize_stack.hpp>
|
|
#include <boost/context/flags.hpp>
|
|
#include <boost/context/preallocated.hpp>
|
|
#include <boost/context/stack_context.hpp>
|
|
|
|
#ifdef BOOST_HAS_ABI_HEADERS
|
|
# include BOOST_ABI_PREFIX
|
|
#endif
|
|
|
|
#if defined(BOOST_MSVC)
|
|
# pragma warning(push)
|
|
# pragma warning(disable: 4702)
|
|
#endif
|
|
|
|
namespace boost {
|
|
namespace context {
|
|
namespace detail {
|
|
|
|
// tampoline function
|
|
// entered if the execution context
|
|
// is resumed for the first time
|
|
template< typename Record >
|
|
static VOID WINAPI fiber_entry_func( LPVOID data) noexcept {
|
|
Record * record = static_cast< Record * >( data);
|
|
BOOST_ASSERT( nullptr != record);
|
|
// start execution of toplevel context-function
|
|
record->run();
|
|
}
|
|
|
|
struct BOOST_CONTEXT_DECL fiber_activation_record {
|
|
LPVOID fiber{ nullptr };
|
|
stack_context sctx{};
|
|
bool main_ctx{ true };
|
|
fiber_activation_record * from{ nullptr };
|
|
std::function< fiber_activation_record*(fiber_activation_record*&) > ontop{};
|
|
bool terminated{ false };
|
|
bool force_unwind{ false };
|
|
|
|
static fiber_activation_record *& current() noexcept;
|
|
|
|
// used for toplevel-context
|
|
// (e.g. main context, thread-entry context)
|
|
fiber_activation_record() noexcept {
|
|
#if ( _WIN32_WINNT > 0x0600)
|
|
if ( ::IsThreadAFiber() ) {
|
|
fiber = ::GetCurrentFiber();
|
|
} else {
|
|
fiber = ::ConvertThreadToFiber( nullptr);
|
|
}
|
|
#else
|
|
fiber = ::ConvertThreadToFiber( nullptr);
|
|
if ( BOOST_UNLIKELY( nullptr == fiber) ) {
|
|
BOOST_ASSERT( ERROR_ALREADY_FIBER == ::GetLastError());
|
|
fiber = ::GetCurrentFiber();
|
|
BOOST_ASSERT( nullptr != fiber);
|
|
BOOST_ASSERT( reinterpret_cast< LPVOID >( 0x1E00) != fiber);
|
|
}
|
|
#endif
|
|
}
|
|
|
|
fiber_activation_record( stack_context sctx_) noexcept :
|
|
sctx{ sctx_ },
|
|
main_ctx{ false } {
|
|
}
|
|
|
|
virtual ~fiber_activation_record() {
|
|
if ( BOOST_UNLIKELY( main_ctx) ) {
|
|
::ConvertFiberToThread();
|
|
} else {
|
|
::DeleteFiber( fiber);
|
|
}
|
|
}
|
|
|
|
fiber_activation_record( fiber_activation_record const&) = delete;
|
|
fiber_activation_record & operator=( fiber_activation_record const&) = delete;
|
|
|
|
bool is_main_context() const noexcept {
|
|
return main_ctx;
|
|
}
|
|
|
|
fiber_activation_record * resume() {
|
|
from = current();
|
|
// store `this` in static, thread local pointer
|
|
// `this` will become the active (running) context
|
|
current() = this;
|
|
// context switch from parent context to `this`-context
|
|
// context switch
|
|
::SwitchToFiber( fiber);
|
|
#if defined(BOOST_NO_CXX14_STD_EXCHANGE)
|
|
return detail::exchange( current()->from, nullptr);
|
|
#else
|
|
return std::exchange( current()->from, nullptr);
|
|
#endif
|
|
}
|
|
|
|
template< typename Ctx, typename Fn >
|
|
fiber_activation_record * resume_with( Fn && fn) {
|
|
from = current();
|
|
// store `this` in static, thread local pointer
|
|
// `this` will become the active (running) context
|
|
// returned by fiber::current()
|
|
current() = this;
|
|
#if defined(BOOST_NO_CXX14_GENERIC_LAMBDAS)
|
|
current()->ontop = std::bind(
|
|
[](typename std::decay< Fn >::type & fn, fiber_activation_record *& ptr){
|
|
Ctx c{ ptr };
|
|
c = fn( std::move( c) );
|
|
if ( ! c) {
|
|
ptr = nullptr;
|
|
}
|
|
#if defined(BOOST_NO_CXX14_STD_EXCHANGE)
|
|
return exchange( c.ptr_, nullptr);
|
|
#else
|
|
return std::exchange( c.ptr_, nullptr);
|
|
#endif
|
|
},
|
|
std::forward< Fn >( fn),
|
|
std::placeholders::_1);
|
|
#else
|
|
current()->ontop = [fn=std::forward<Fn>(fn)](fiber_activation_record *& ptr){
|
|
Ctx c{ ptr };
|
|
c = fn( std::move( c) );
|
|
if ( ! c) {
|
|
ptr = nullptr;
|
|
}
|
|
#if defined(BOOST_NO_CXX14_STD_EXCHANGE)
|
|
return exchange( c.ptr_, nullptr);
|
|
#else
|
|
return std::exchange( c.ptr_, nullptr);
|
|
#endif
|
|
};
|
|
#endif
|
|
// context switch
|
|
::SwitchToFiber( fiber);
|
|
#if defined(BOOST_NO_CXX14_STD_EXCHANGE)
|
|
return detail::exchange( current()->from, nullptr);
|
|
#else
|
|
return std::exchange( current()->from, nullptr);
|
|
#endif
|
|
}
|
|
|
|
virtual void deallocate() noexcept {
|
|
}
|
|
};
|
|
|
|
struct BOOST_CONTEXT_DECL fiber_activation_record_initializer {
|
|
fiber_activation_record_initializer() noexcept;
|
|
~fiber_activation_record_initializer();
|
|
};
|
|
|
|
struct forced_unwind {
|
|
fiber_activation_record * from{ nullptr };
|
|
|
|
explicit forced_unwind( fiber_activation_record * from_) :
|
|
from{ from_ } {
|
|
}
|
|
};
|
|
|
|
template< typename Ctx, typename StackAlloc, typename Fn >
|
|
class fiber_capture_record : public fiber_activation_record {
|
|
private:
|
|
typename std::decay< StackAlloc >::type salloc_;
|
|
typename std::decay< Fn >::type fn_;
|
|
|
|
static void destroy( fiber_capture_record * p) noexcept {
|
|
typename std::decay< StackAlloc >::type salloc = std::move( p->salloc_);
|
|
stack_context sctx = p->sctx;
|
|
// deallocate activation record
|
|
p->~fiber_capture_record();
|
|
// destroy stack with stack allocator
|
|
salloc.deallocate( sctx);
|
|
}
|
|
|
|
public:
|
|
fiber_capture_record( stack_context sctx, StackAlloc && salloc, Fn && fn) noexcept :
|
|
fiber_activation_record( sctx),
|
|
salloc_( std::forward< StackAlloc >( salloc)),
|
|
fn_( std::forward< Fn >( fn) ) {
|
|
}
|
|
|
|
void deallocate() noexcept override final {
|
|
BOOST_ASSERT( main_ctx || ( ! main_ctx && terminated) );
|
|
destroy( this);
|
|
}
|
|
|
|
void run() {
|
|
Ctx c{ from };
|
|
try {
|
|
// invoke context-function
|
|
#if defined(BOOST_NO_CXX17_STD_INVOKE)
|
|
c = boost::context::detail::invoke( fn_, std::move( c) );
|
|
#else
|
|
c = std::invoke( fn_, std::move( c) );
|
|
#endif
|
|
} catch ( forced_unwind const& ex) {
|
|
c = Ctx{ ex.from };
|
|
}
|
|
// this context has finished its task
|
|
from = nullptr;
|
|
ontop = nullptr;
|
|
terminated = true;
|
|
force_unwind = false;
|
|
std::move( c).resume();
|
|
BOOST_ASSERT_MSG( false, "fiber already terminated");
|
|
}
|
|
};
|
|
|
|
template< typename Ctx, typename StackAlloc, typename Fn >
|
|
static fiber_activation_record * create_fiber1( StackAlloc && salloc, Fn && fn) {
|
|
typedef fiber_capture_record< Ctx, StackAlloc, Fn > capture_t;
|
|
|
|
auto sctx = salloc.allocate();
|
|
BOOST_ASSERT( ( sizeof( capture_t) ) < sctx.size);
|
|
// reserve space for control structure
|
|
void * storage = reinterpret_cast< void * >(
|
|
( reinterpret_cast< uintptr_t >( sctx.sp) - static_cast< uintptr_t >( sizeof( capture_t) ) )
|
|
& ~ static_cast< uintptr_t >( 0xff) );
|
|
// placment new for control structure on context stack
|
|
capture_t * record = new ( storage) capture_t{
|
|
sctx, std::forward< StackAlloc >( salloc), std::forward< Fn >( fn) };
|
|
// create user-context
|
|
record->fiber = ::CreateFiber( sctx.size, & detail::fiber_entry_func< capture_t >, record);
|
|
return record;
|
|
}
|
|
|
|
template< typename Ctx, typename StackAlloc, typename Fn >
|
|
static fiber_activation_record * create_fiber2( preallocated palloc, StackAlloc && salloc, Fn && fn) {
|
|
typedef fiber_capture_record< Ctx, StackAlloc, Fn > capture_t;
|
|
|
|
BOOST_ASSERT( ( sizeof( capture_t) ) < palloc.size);
|
|
// reserve space for control structure
|
|
void * storage = reinterpret_cast< void * >(
|
|
( reinterpret_cast< uintptr_t >( palloc.sp) - static_cast< uintptr_t >( sizeof( capture_t) ) )
|
|
& ~ static_cast< uintptr_t >( 0xff) );
|
|
// placment new for control structure on context stack
|
|
capture_t * record = new ( storage) capture_t{
|
|
palloc.sctx, std::forward< StackAlloc >( salloc), std::forward< Fn >( fn) };
|
|
// create user-context
|
|
record->fiber = ::CreateFiber( palloc.sctx.size, & detail::fiber_entry_func< capture_t >, record);
|
|
return record;
|
|
}
|
|
|
|
}
|
|
|
|
class BOOST_CONTEXT_DECL fiber {
|
|
private:
|
|
friend struct detail::fiber_activation_record;
|
|
|
|
template< typename Ctx, typename StackAlloc, typename Fn >
|
|
friend class detail::fiber_capture_record;
|
|
|
|
template< typename Ctx, typename StackAlloc, typename Fn >
|
|
friend detail::fiber_activation_record * detail::create_fiber1( StackAlloc &&, Fn &&);
|
|
|
|
template< typename Ctx, typename StackAlloc, typename Fn >
|
|
friend detail::fiber_activation_record * detail::create_fiber2( preallocated, StackAlloc &&, Fn &&);
|
|
|
|
template< typename StackAlloc, typename Fn >
|
|
friend fiber
|
|
callcc( std::allocator_arg_t, StackAlloc &&, Fn &&);
|
|
|
|
template< typename StackAlloc, typename Fn >
|
|
friend fiber
|
|
callcc( std::allocator_arg_t, preallocated, StackAlloc &&, Fn &&);
|
|
|
|
detail::fiber_activation_record * ptr_{ nullptr };
|
|
|
|
fiber( detail::fiber_activation_record * ptr) noexcept :
|
|
ptr_{ ptr } {
|
|
}
|
|
|
|
public:
|
|
fiber() = default;
|
|
|
|
template< typename Fn, typename = detail::disable_overload< fiber, Fn > >
|
|
fiber( Fn && fn) :
|
|
fiber{ std::allocator_arg,
|
|
fixedsize_stack(),
|
|
std::forward< Fn >( fn) } {
|
|
}
|
|
|
|
template< typename StackAlloc, typename Fn >
|
|
fiber( std::allocator_arg_t, StackAlloc && salloc, Fn && fn) :
|
|
ptr_{ detail::create_fiber1< fiber >(
|
|
std::forward< StackAlloc >( salloc), std::forward< Fn >( fn) ) } {;
|
|
}
|
|
|
|
template< typename StackAlloc, typename Fn >
|
|
fiber( std::allocator_arg_t, preallocated palloc, StackAlloc && salloc, Fn && fn) :
|
|
ptr_{ detail::create_fiber2< fiber >(
|
|
palloc, std::forward< StackAlloc >( salloc), std::forward< Fn >( fn) ) } {
|
|
}
|
|
|
|
~fiber() {
|
|
if ( BOOST_UNLIKELY( nullptr != ptr_) && ! ptr_->main_ctx) {
|
|
if ( BOOST_LIKELY( ! ptr_->terminated) ) {
|
|
ptr_->force_unwind = true;
|
|
ptr_->resume();
|
|
BOOST_ASSERT( ptr_->terminated);
|
|
}
|
|
ptr_->deallocate();
|
|
}
|
|
}
|
|
|
|
fiber( fiber const&) = delete;
|
|
fiber & operator=( fiber const&) = delete;
|
|
|
|
fiber( fiber && other) noexcept {
|
|
swap( other);
|
|
}
|
|
|
|
fiber & operator=( fiber && other) noexcept {
|
|
if ( BOOST_LIKELY( this != & other) ) {
|
|
fiber tmp = std::move( other);
|
|
swap( tmp);
|
|
}
|
|
return * this;
|
|
}
|
|
|
|
fiber resume() && {
|
|
BOOST_ASSERT( nullptr != ptr_);
|
|
#if defined(BOOST_NO_CXX14_STD_EXCHANGE)
|
|
detail::fiber_activation_record * ptr = detail::exchange( ptr_, nullptr)->resume();
|
|
#else
|
|
detail::fiber_activation_record * ptr = std::exchange( ptr_, nullptr)->resume();
|
|
#endif
|
|
if ( BOOST_UNLIKELY( detail::fiber_activation_record::current()->force_unwind) ) {
|
|
throw detail::forced_unwind{ ptr};
|
|
} else if ( BOOST_UNLIKELY( nullptr != detail::fiber_activation_record::current()->ontop) ) {
|
|
ptr = detail::fiber_activation_record::current()->ontop( ptr);
|
|
detail::fiber_activation_record::current()->ontop = nullptr;
|
|
}
|
|
return { ptr };
|
|
}
|
|
|
|
template< typename Fn >
|
|
fiber resume_with( Fn && fn) && {
|
|
BOOST_ASSERT( nullptr != ptr_);
|
|
#if defined(BOOST_NO_CXX14_STD_EXCHANGE)
|
|
detail::fiber_activation_record * ptr =
|
|
detail::exchange( ptr_, nullptr)->resume_with< fiber >( std::forward< Fn >( fn) );
|
|
#else
|
|
detail::fiber_activation_record * ptr =
|
|
std::exchange( ptr_, nullptr)->resume_with< fiber >( std::forward< Fn >( fn) );
|
|
#endif
|
|
if ( BOOST_UNLIKELY( detail::fiber_activation_record::current()->force_unwind) ) {
|
|
throw detail::forced_unwind{ ptr};
|
|
} else if ( BOOST_UNLIKELY( nullptr != detail::fiber_activation_record::current()->ontop) ) {
|
|
ptr = detail::fiber_activation_record::current()->ontop( ptr);
|
|
detail::fiber_activation_record::current()->ontop = nullptr;
|
|
}
|
|
return { ptr };
|
|
}
|
|
|
|
explicit operator bool() const noexcept {
|
|
return nullptr != ptr_ && ! ptr_->terminated;
|
|
}
|
|
|
|
bool operator!() const noexcept {
|
|
return nullptr == ptr_ || ptr_->terminated;
|
|
}
|
|
|
|
bool operator<( fiber const& other) const noexcept {
|
|
return ptr_ < other.ptr_;
|
|
}
|
|
|
|
#if !defined(BOOST_EMBTC)
|
|
|
|
template< typename charT, class traitsT >
|
|
friend std::basic_ostream< charT, traitsT > &
|
|
operator<<( std::basic_ostream< charT, traitsT > & os, fiber const& other) {
|
|
if ( nullptr != other.ptr_) {
|
|
return os << other.ptr_;
|
|
} else {
|
|
return os << "{not-a-context}";
|
|
}
|
|
}
|
|
|
|
#else
|
|
|
|
template< typename charT, class traitsT >
|
|
friend std::basic_ostream< charT, traitsT > &
|
|
operator<<( std::basic_ostream< charT, traitsT > & os, fiber const& other);
|
|
|
|
#endif
|
|
|
|
void swap( fiber & other) noexcept {
|
|
std::swap( ptr_, other.ptr_);
|
|
}
|
|
};
|
|
|
|
#if defined(BOOST_EMBTC)
|
|
|
|
template< typename charT, class traitsT >
|
|
inline std::basic_ostream< charT, traitsT > &
|
|
operator<<( std::basic_ostream< charT, traitsT > & os, fiber const& other) {
|
|
if ( nullptr != other.ptr_) {
|
|
return os << other.ptr_;
|
|
} else {
|
|
return os << "{not-a-context}";
|
|
}
|
|
}
|
|
|
|
#endif
|
|
|
|
inline
|
|
void swap( fiber & l, fiber & r) noexcept {
|
|
l.swap( r);
|
|
}
|
|
|
|
typedef fiber fiber_context;
|
|
|
|
}}
|
|
|
|
#if defined(BOOST_MSVC)
|
|
# pragma warning(pop)
|
|
#endif
|
|
|
|
#ifdef BOOST_HAS_ABI_HEADERS
|
|
# include BOOST_ABI_SUFFIX
|
|
#endif
|
|
|
|
#endif // BOOST_CONTEXT_FIBER_H
|