/usr/include/pplx/pplxcancellation_token.h is in libcpprest-dev 2.8.0-2.
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* ==++==
*
* Copyright (c) Microsoft Corporation. All rights reserved.
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*
* ==--==
* =+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+=+
*
* Parallel Patterns Library : cancellation_token
*
* =-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
****/
#pragma once
#ifndef _PPLX_H
#error This header must not be included directly
#endif
#ifndef _PPLXCANCELLATION_TOKEN_H
#define _PPLXCANCELLATION_TOKEN_H
#if (defined(_MSC_VER) && (_MSC_VER >= 1800)) && !CPPREST_FORCE_PPLX
#error This file must not be included for Visual Studio 12 or later
#endif
#include <cstdlib>
#include <string>
#include "pplx/pplxinterface.h"
#pragma pack(push,_CRT_PACKING)
// All header files are required to be protected from the macro new
#pragma push_macro("new")
#undef new
namespace pplx
{
/// <summary>
/// This class describes an exception thrown by the PPL tasks layer in order to force the current task
/// to cancel. It is also thrown by the <c>get()</c> method on <see cref="task Class">task</see>, for a
/// canceled task.
/// </summary>
/// <seealso cref="task::get Method"/>
/// <seealso cref="cancel_current_task Method"/>
/**/
class task_canceled : public std::exception
{
private:
std::string _message;
public:
/// <summary>
/// Constructs a <c>task_canceled</c> object.
/// </summary>
/// <param name="_Message">
/// A descriptive message of the error.
/// </param>
/**/
explicit task_canceled(_In_z_ const char * _Message) throw()
: _message(_Message)
{
}
/// <summary>
/// Constructs a <c>task_canceled</c> object.
/// </summary>
/**/
task_canceled() throw()
: exception()
{
}
~task_canceled() throw () {}
const char* what() const CPPREST_NOEXCEPT
{
return _message.c_str();
}
};
/// <summary>
/// This class describes an exception thrown when an invalid operation is performed that is not more accurately
/// described by another exception type thrown by the Concurrency Runtime.
/// </summary>
/// <remarks>
/// The various methods which throw this exception will generally document under what circumstances they will throw it.
/// </remarks>
/**/
class invalid_operation : public std::exception
{
private:
std::string _message;
public:
/// <summary>
/// Constructs an <c>invalid_operation</c> object.
/// </summary>
/// <param name="_Message">
/// A descriptive message of the error.
/// </param>
/**/
invalid_operation(_In_z_ const char * _Message) throw()
: _message(_Message)
{
}
/// <summary>
/// Constructs an <c>invalid_operation</c> object.
/// </summary>
/**/
invalid_operation() throw()
: exception()
{
}
~invalid_operation() throw () {}
const char* what() const CPPREST_NOEXCEPT
{
return _message.c_str();
}
};
namespace details
{
// Base class for all reference counted objects
class _RefCounter
{
public:
virtual ~_RefCounter()
{
_ASSERTE(_M_refCount == 0);
}
// Acquires a reference
// Returns the new reference count.
long _Reference()
{
long _Refcount = atomic_increment(_M_refCount);
// 0 - 1 transition is illegal
_ASSERTE(_Refcount > 1);
return _Refcount;
}
// Releases the reference
// Returns the new reference count
long _Release()
{
long _Refcount = atomic_decrement(_M_refCount);
_ASSERTE(_Refcount >= 0);
if (_Refcount == 0)
{
_Destroy();
}
return _Refcount;
}
protected:
// Allow derived classes to provide their own deleter
virtual void _Destroy()
{
delete this;
}
// Only allow instantiation through derived class
_RefCounter(long _InitialCount = 1) : _M_refCount(_InitialCount)
{
_ASSERTE(_M_refCount > 0);
}
// Reference count
atomic_long _M_refCount;
};
class _CancellationTokenState;
class _CancellationTokenRegistration : public _RefCounter
{
private:
static const long _STATE_CLEAR = 0;
static const long _STATE_DEFER_DELETE = 1;
static const long _STATE_SYNCHRONIZE = 2;
static const long _STATE_CALLED = 3;
public:
_CancellationTokenRegistration(long _InitialRefs = 1) :
_RefCounter(_InitialRefs),
_M_state(_STATE_CALLED),
_M_pTokenState(NULL)
{
}
_CancellationTokenState *_GetToken() const
{
return _M_pTokenState;
}
protected:
virtual ~_CancellationTokenRegistration()
{
_ASSERTE(_M_state != _STATE_CLEAR);
}
virtual void _Exec() = 0;
private:
friend class _CancellationTokenState;
void _Invoke()
{
long tid = ::pplx::details::platform::GetCurrentThreadId();
_ASSERTE((tid & 0x3) == 0); // If this ever fires, we need a different encoding for this.
long result = atomic_compare_exchange(_M_state, tid, _STATE_CLEAR);
if (result == _STATE_CLEAR)
{
_Exec();
result = atomic_compare_exchange(_M_state, _STATE_CALLED, tid);
if (result == _STATE_SYNCHRONIZE)
{
_M_pSyncBlock->set();
}
}
_Release();
}
atomic_long _M_state;
extensibility::event_t *_M_pSyncBlock;
_CancellationTokenState *_M_pTokenState;
};
template<typename _Function>
class _CancellationTokenCallback : public _CancellationTokenRegistration
{
public:
_CancellationTokenCallback(const _Function& _Func) :
_M_function(_Func)
{
}
protected:
virtual void _Exec()
{
_M_function();
}
private:
_Function _M_function;
};
class CancellationTokenRegistration_TaskProc : public _CancellationTokenRegistration
{
public:
CancellationTokenRegistration_TaskProc(TaskProc_t proc, _In_ void *pData, int initialRefs) :
_CancellationTokenRegistration(initialRefs), m_proc(proc), m_pData(pData)
{
}
protected:
virtual void _Exec()
{
m_proc(m_pData);
}
private:
TaskProc_t m_proc;
void *m_pData;
};
// The base implementation of a cancellation token.
class _CancellationTokenState : public _RefCounter
{
protected:
class TokenRegistrationContainer
{
private:
typedef struct _Node {
_CancellationTokenRegistration* _M_token;
_Node *_M_next;
} Node;
public:
TokenRegistrationContainer() : _M_begin(nullptr), _M_last(nullptr)
{
}
~TokenRegistrationContainer()
{
#if defined(_MSC_VER)
#pragma warning(push)
#pragma warning(disable: 6001)
#endif
auto node = _M_begin;
while (node != nullptr)
{
Node* tmp = node;
node = node->_M_next;
::free(tmp);
}
#if defined(_MSC_VER)
#pragma warning(pop)
#endif
}
void swap(TokenRegistrationContainer& list)
{
std::swap(list._M_begin, _M_begin);
std::swap(list._M_last, _M_last);
}
bool empty()
{
return _M_begin == nullptr;
}
template<typename T>
void for_each(T lambda)
{
Node* node = _M_begin;
while (node != nullptr)
{
lambda(node->_M_token);
node = node->_M_next;
}
}
void push_back(_CancellationTokenRegistration* token)
{
Node* node = reinterpret_cast<Node*>(::malloc(sizeof(Node)));
if (node == nullptr)
{
throw ::std::bad_alloc();
}
node->_M_token = token;
node->_M_next = nullptr;
if (_M_begin == nullptr)
{
_M_begin = node;
}
else
{
_M_last->_M_next = node;
}
_M_last = node;
}
void remove(_CancellationTokenRegistration* token)
{
Node* node = _M_begin;
Node* prev = nullptr;
while (node != nullptr)
{
if (node->_M_token == token) {
if (prev == nullptr)
{
_M_begin = node->_M_next;
}
else
{
prev->_M_next = node->_M_next;
}
if (node->_M_next == nullptr)
{
_M_last = prev;
}
::free(node);
break;
}
prev = node;
node = node->_M_next;
}
}
private:
Node *_M_begin;
Node *_M_last;
};
public:
static _CancellationTokenState * _NewTokenState()
{
return new _CancellationTokenState();
}
static _CancellationTokenState *_None()
{
return reinterpret_cast<_CancellationTokenState *>(2);
}
static bool _IsValid(_In_opt_ _CancellationTokenState *_PToken)
{
return (_PToken != NULL && _PToken != _None());
}
_CancellationTokenState() :
_M_stateFlag(0)
{
}
~_CancellationTokenState()
{
TokenRegistrationContainer rundownList;
{
extensibility::scoped_critical_section_t _Lock(_M_listLock);
_M_registrations.swap(rundownList);
}
rundownList.for_each([](_CancellationTokenRegistration * pRegistration)
{
pRegistration->_M_state = _CancellationTokenRegistration::_STATE_SYNCHRONIZE;
pRegistration->_Release();
});
}
bool _IsCanceled() const
{
return (_M_stateFlag != 0);
}
void _Cancel()
{
if (atomic_compare_exchange(_M_stateFlag, 1l, 0l) == 0)
{
TokenRegistrationContainer rundownList;
{
extensibility::scoped_critical_section_t _Lock(_M_listLock);
_M_registrations.swap(rundownList);
}
rundownList.for_each([](_CancellationTokenRegistration * pRegistration)
{
pRegistration->_Invoke();
});
_M_stateFlag = 2;
_M_cancelComplete.set();
}
}
_CancellationTokenRegistration *_RegisterCallback(TaskProc_t _PCallback, _In_ void *_PData, int _InitialRefs = 1)
{
_CancellationTokenRegistration *pRegistration = new CancellationTokenRegistration_TaskProc(_PCallback, _PData, _InitialRefs);
_RegisterCallback(pRegistration);
return pRegistration;
}
void _RegisterCallback(_In_ _CancellationTokenRegistration *_PRegistration)
{
_PRegistration->_M_state = _CancellationTokenRegistration::_STATE_CLEAR;
_PRegistration->_Reference();
_PRegistration->_M_pTokenState = this;
bool invoke = true;
if (!_IsCanceled())
{
extensibility::scoped_critical_section_t _Lock(_M_listLock);
if (!_IsCanceled())
{
invoke = false;
_M_registrations.push_back(_PRegistration);
}
}
if (invoke)
{
_PRegistration->_Invoke();
}
}
void _DeregisterCallback(_In_ _CancellationTokenRegistration *_PRegistration)
{
bool synchronize = false;
{
extensibility::scoped_critical_section_t _Lock(_M_listLock);
//
// If a cancellation has occurred, the registration list is guaranteed to be empty if we've observed it under the auspices of the
// lock. In this case, we must synchronize with the cancelling thread to guarantee that the cancellation is finished by the time
// we return from this method.
//
if (!_M_registrations.empty())
{
_M_registrations.remove(_PRegistration);
_PRegistration->_M_state = _CancellationTokenRegistration::_STATE_SYNCHRONIZE;
_PRegistration->_Release();
}
else
{
synchronize = true;
}
}
//
// If the list is empty, we are in one of several situations:
//
// - The callback has already been made --> do nothing
// - The callback is about to be made --> flag it so it doesn't happen and return
// - The callback is in progress elsewhere --> synchronize with it
// - The callback is in progress on this thread --> do nothing
//
if (synchronize)
{
long result = atomic_compare_exchange(
_PRegistration->_M_state,
_CancellationTokenRegistration::_STATE_DEFER_DELETE,
_CancellationTokenRegistration::_STATE_CLEAR
);
switch(result)
{
case _CancellationTokenRegistration::_STATE_CLEAR:
case _CancellationTokenRegistration::_STATE_CALLED:
break;
case _CancellationTokenRegistration::_STATE_DEFER_DELETE:
case _CancellationTokenRegistration::_STATE_SYNCHRONIZE:
_ASSERTE(false);
break;
default:
{
long tid = result;
if (tid == ::pplx::details::platform::GetCurrentThreadId())
{
//
// It is entirely legal for a caller to Deregister during a callback instead of having to provide their own synchronization
// mechanism between the two. In this case, we do *NOT* need to explicitly synchronize with the callback as doing so would
// deadlock. If the call happens during, skip any extra synchronization.
//
break;
}
extensibility::event_t ev;
_PRegistration->_M_pSyncBlock = &ev;
long result_1 = atomic_exchange(_PRegistration->_M_state, _CancellationTokenRegistration::_STATE_SYNCHRONIZE);
if (result_1 != _CancellationTokenRegistration::_STATE_CALLED)
{
_PRegistration->_M_pSyncBlock->wait(::pplx::extensibility::event_t::timeout_infinite);
}
break;
}
}
}
}
private:
// The flag for the token state (whether it is canceled or not)
atomic_long _M_stateFlag;
// Notification of completion of cancellation of this token.
extensibility::event_t _M_cancelComplete; // Hmm.. where do we wait for it??
// Lock to protect the registrations list
extensibility::critical_section_t _M_listLock;
// The protected list of registrations
TokenRegistrationContainer _M_registrations;
};
} // namespace details
class cancellation_token_source;
class cancellation_token;
/// <summary>
/// The <c>cancellation_token_registration</c> class represents a callback notification from a <c>cancellation_token</c>. When the <c>register</c>
/// method on a <c>cancellation_token</c> is used to receive notification of when cancellation occurs, a <c>cancellation_token_registration</c>
/// object is returned as a handle to the callback so that the caller can request a specific callback no longer be made through use of
/// the <c>deregister</c> method.
/// </summary>
class cancellation_token_registration
{
public:
cancellation_token_registration() :
_M_pRegistration(NULL)
{
}
~cancellation_token_registration()
{
_Clear();
}
cancellation_token_registration(const cancellation_token_registration& _Src)
{
_Assign(_Src._M_pRegistration);
}
cancellation_token_registration(cancellation_token_registration&& _Src)
{
_Move(_Src._M_pRegistration);
}
cancellation_token_registration& operator=(const cancellation_token_registration& _Src)
{
if (this != &_Src)
{
_Clear();
_Assign(_Src._M_pRegistration);
}
return *this;
}
cancellation_token_registration& operator=(cancellation_token_registration&& _Src)
{
if (this != &_Src)
{
_Clear();
_Move(_Src._M_pRegistration);
}
return *this;
}
bool operator==(const cancellation_token_registration& _Rhs) const
{
return _M_pRegistration == _Rhs._M_pRegistration;
}
bool operator!=(const cancellation_token_registration& _Rhs) const
{
return !(operator==(_Rhs));
}
private:
friend class cancellation_token;
cancellation_token_registration(_In_ details::_CancellationTokenRegistration *_PRegistration) :
_M_pRegistration(_PRegistration)
{
}
void _Clear()
{
if (_M_pRegistration != NULL)
{
_M_pRegistration->_Release();
}
_M_pRegistration = NULL;
}
void _Assign(_In_ details::_CancellationTokenRegistration *_PRegistration)
{
if (_PRegistration != NULL)
{
_PRegistration->_Reference();
}
_M_pRegistration = _PRegistration;
}
void _Move(_In_ details::_CancellationTokenRegistration *&_PRegistration)
{
_M_pRegistration = _PRegistration;
_PRegistration = NULL;
}
details::_CancellationTokenRegistration *_M_pRegistration;
};
/// <summary>
/// The <c>cancellation_token</c> class represents the ability to determine whether some operation has been requested to cancel. A given token can
/// be associated with a <c>task_group</c>, <c>structured_task_group</c>, or <c>task</c> to provide implicit cancellation. It can also be polled for
/// cancellation or have a callback registered for if and when the associated <c>cancellation_token_source</c> is canceled.
/// </summary>
class cancellation_token
{
public:
typedef details::_CancellationTokenState * _ImplType;
/// <summary>
/// Returns a cancellation token which can never be subject to cancellation.
/// </summary>
/// <returns>
/// A cancellation token that cannot be canceled.
/// </returns>
static cancellation_token none()
{
return cancellation_token();
}
cancellation_token(const cancellation_token& _Src)
{
_Assign(_Src._M_Impl);
}
cancellation_token(cancellation_token&& _Src)
{
_Move(_Src._M_Impl);
}
cancellation_token& operator=(const cancellation_token& _Src)
{
if (this != &_Src)
{
_Clear();
_Assign(_Src._M_Impl);
}
return *this;
}
cancellation_token& operator=(cancellation_token&& _Src)
{
if (this != &_Src)
{
_Clear();
_Move(_Src._M_Impl);
}
return *this;
}
bool operator==(const cancellation_token& _Src) const
{
return _M_Impl == _Src._M_Impl;
}
bool operator!=(const cancellation_token& _Src) const
{
return !(operator==(_Src));
}
~cancellation_token()
{
_Clear();
}
/// <summary>
/// Returns an indication of whether this token can be canceled or not.
/// </summary>
/// <returns>
/// An indication of whether this token can be canceled or not.
/// </returns>
bool is_cancelable() const
{
return (_M_Impl != NULL);
}
/// <summary>
/// Returns <c>true</c> if the token has been canceled.
/// </summary>
/// <returns>
/// The value <c>true</c> if the token has been canceled; otherwise, the value <c>false</c>.
/// </returns>
bool is_canceled() const
{
return (_M_Impl != NULL && _M_Impl->_IsCanceled());
}
/// <summary>
/// Registers a callback function with the token. If and when the token is canceled, the callback will be made. Note that if the token
/// is already canceled at the point where this method is called, the callback will be made immediately and synchronously.
/// </summary>
/// <typeparam name="_Function">
/// The type of the function object that will be called back when this <c>cancellation_token</c> is canceled.
/// </typeparam>
/// <param name="_Func">
/// The function object that will be called back when this <c>cancellation_token</c> is canceled.
/// </param>
/// <returns>
/// A <c>cancellation_token_registration</c> object which can be utilized in the <c>deregister</c> method to deregister a previously registered
/// callback and prevent it from being made. The method will throw an <see cref="invalid_operation Class">invalid_operation </see> exception if
/// it is called on a <c>cancellation_token</c> object that was created using the <see cref="cancellation_token::none Method">cancellation_token::none </see>
/// method.
/// </returns>
template<typename _Function>
::pplx::cancellation_token_registration register_callback(const _Function& _Func) const
{
if (_M_Impl == NULL)
{
// A callback cannot be registered if the token does not have an associated source.
throw invalid_operation();
}
#if defined(_MSC_VER)
#pragma warning(suppress: 28197)
#endif
details::_CancellationTokenCallback<_Function> *_PCallback = new details::_CancellationTokenCallback<_Function>(_Func);
_M_Impl->_RegisterCallback(_PCallback);
return cancellation_token_registration(_PCallback);
}
/// <summary>
/// Removes a callback previously registered via the <c>register</c> method based on the <c>cancellation_token_registration</c> object returned
/// at the time of registration.
/// </summary>
/// <param name="_Registration">
/// The <c>cancellation_token_registration</c> object corresponding to the callback to be deregistered. This token must have been previously
/// returned from a call to the <c>register</c> method.
/// </param>
void deregister_callback(const cancellation_token_registration& _Registration) const
{
_M_Impl->_DeregisterCallback(_Registration._M_pRegistration);
}
_ImplType _GetImpl() const
{
return _M_Impl;
}
_ImplType _GetImplValue() const
{
return (_M_Impl == NULL) ? ::pplx::details::_CancellationTokenState::_None() : _M_Impl;
}
static cancellation_token _FromImpl(_ImplType _Impl)
{
return cancellation_token(_Impl);
}
private:
friend class cancellation_token_source;
_ImplType _M_Impl;
void _Clear()
{
if (_M_Impl != NULL)
{
_M_Impl->_Release();
}
_M_Impl = NULL;
}
void _Assign(_ImplType _Impl)
{
if (_Impl != NULL)
{
_Impl->_Reference();
}
_M_Impl = _Impl;
}
void _Move(_ImplType &_Impl)
{
_M_Impl = _Impl;
_Impl = NULL;
}
cancellation_token() :
_M_Impl(NULL)
{
}
cancellation_token(_ImplType _Impl) :
_M_Impl(_Impl)
{
if (_M_Impl == ::pplx::details::_CancellationTokenState::_None())
{
_M_Impl = NULL;
}
if (_M_Impl != NULL)
{
_M_Impl->_Reference();
}
}
};
/// <summary>
/// The <c>cancellation_token_source</c> class represents the ability to cancel some cancelable operation.
/// </summary>
class cancellation_token_source
{
public:
typedef ::pplx::details::_CancellationTokenState * _ImplType;
/// <summary>
/// Constructs a new <c>cancellation_token_source</c>. The source can be used to flag cancellation of some cancelable operation.
/// </summary>
cancellation_token_source()
{
_M_Impl = new ::pplx::details::_CancellationTokenState;
}
cancellation_token_source(const cancellation_token_source& _Src)
{
_Assign(_Src._M_Impl);
}
cancellation_token_source(cancellation_token_source&& _Src)
{
_Move(_Src._M_Impl);
}
cancellation_token_source& operator=(const cancellation_token_source& _Src)
{
if (this != &_Src)
{
_Clear();
_Assign(_Src._M_Impl);
}
return *this;
}
cancellation_token_source& operator=(cancellation_token_source&& _Src)
{
if (this != &_Src)
{
_Clear();
_Move(_Src._M_Impl);
}
return *this;
}
bool operator==(const cancellation_token_source& _Src) const
{
return _M_Impl == _Src._M_Impl;
}
bool operator!=(const cancellation_token_source& _Src) const
{
return !(operator==(_Src));
}
~cancellation_token_source()
{
if (_M_Impl != NULL)
{
_M_Impl->_Release();
}
}
/// <summary>
/// Returns a cancellation token associated with this source. The returned token can be polled for cancellation
/// or provide a callback if and when cancellation occurs.
/// </summary>
/// <returns>
/// A cancellation token associated with this source.
/// </returns>
cancellation_token get_token() const
{
return cancellation_token(_M_Impl);
}
/// <summary>
/// Creates a <c>cancellation_token_source</c> which is canceled when the provided token is canceled.
/// </summary>
/// <param name="_Src">
/// A token whose cancellation will cause cancellation of the returned token source. Note that the returned token source can also be canceled
/// independently of the source contained in this parameter.
/// </param>
/// <returns>
/// A <c>cancellation_token_source</c> which is canceled when the token provided by the <paramref name="_Src"/> parameter is canceled.
/// </returns>
static cancellation_token_source create_linked_source(cancellation_token& _Src)
{
cancellation_token_source newSource;
_Src.register_callback( [newSource](){ newSource.cancel(); } );
return newSource;
}
/// <summary>
/// Creates a <c>cancellation_token_source</c> which is canceled when one of a series of tokens represented by an STL iterator
/// pair is canceled.
/// </summary>
/// <param name="_Begin">
/// The STL iterator corresponding to the beginning of the range of tokens to listen for cancellation of.
/// </param>
/// <param name="_End">
/// The STL iterator corresponding to the ending of the range of tokens to listen for cancellation of.
/// </param>
/// <returns>
/// A <c>cancellation_token_source</c> which is canceled when any of the tokens provided by the range described by the STL iterators
/// contained in the <paramref name="_Begin"/> and <paramref name="_End"/> parameters is canceled.
/// </returns>
template<typename _Iter>
static cancellation_token_source create_linked_source(_Iter _Begin, _Iter _End)
{
cancellation_token_source newSource;
for (_Iter _It = _Begin; _It != _End; ++_It)
{
_It->register_callback( [newSource](){ newSource.cancel(); } );
}
return newSource;
}
/// <summary>
/// Cancels the token. Any <c>task_group</c>, <c>structured_task_group</c>, or <c>task</c> which utilizes the token will be
/// canceled upon this call and throw an exception at the next interruption point.
/// </summary>
void cancel() const
{
_M_Impl->_Cancel();
}
_ImplType _GetImpl() const
{
return _M_Impl;
}
static cancellation_token_source _FromImpl(_ImplType _Impl)
{
return cancellation_token_source(_Impl);
}
private:
_ImplType _M_Impl;
void _Clear()
{
if (_M_Impl != NULL)
{
_M_Impl->_Release();
}
_M_Impl = NULL;
}
void _Assign(_ImplType _Impl)
{
if (_Impl != NULL)
{
_Impl->_Reference();
}
_M_Impl = _Impl;
}
void _Move(_ImplType &_Impl)
{
_M_Impl = _Impl;
_Impl = NULL;
}
cancellation_token_source(_ImplType _Impl) :
_M_Impl(_Impl)
{
if (_M_Impl == ::pplx::details::_CancellationTokenState::_None())
{
_M_Impl = NULL;
}
if (_M_Impl != NULL)
{
_M_Impl->_Reference();
}
}
};
} // namespace pplx
#pragma pop_macro("new")
#pragma pack(pop)
#endif // _PPLXCANCELLATION_TOKEN_H
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