exception_ptr.h
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// Exception Handling support header (exception_ptr class) for -*- C++ -*-
// Copyright (C) 2008-2021 Free Software Foundation, Inc.
//
// This file is part of GCC.
//
// GCC is free software; you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation; either version 3, or (at your option)
// any later version.
//
// GCC is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// Under Section 7 of GPL version 3, you are granted additional
// permissions described in the GCC Runtime Library Exception, version
// 3.1, as published by the Free Software Foundation.
// You should have received a copy of the GNU General Public License and
// a copy of the GCC Runtime Library Exception along with this program;
// see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
// <http://www.gnu.org/licenses/>.
/** @file bits/exception_ptr.h
* This is an internal header file, included by other library headers.
* Do not attempt to use it directly. @headername{exception}
*/
#ifndef _EXCEPTION_PTR_H
#define _EXCEPTION_PTR_H
#pragma GCC visibility push(default)
#include <bits/c++config.h>
#include <bits/exception_defines.h>
#include <bits/cxxabi_init_exception.h>
#include <typeinfo>
#include <new>
#ifdef _GLIBCXX_EH_PTR_RELOPS_COMPAT
# define _GLIBCXX_EH_PTR_USED __attribute__((__used__))
#else
# define _GLIBCXX_EH_PTR_USED
#endif
extern "C++" {
namespace std
{
class type_info;
/**
* @addtogroup exceptions
* @{
*/
namespace __exception_ptr
{
class exception_ptr;
}
using __exception_ptr::exception_ptr;
/** Obtain an exception_ptr to the currently handled exception. If there
* is none, or the currently handled exception is foreign, return the null
* value.
*/
exception_ptr current_exception() _GLIBCXX_USE_NOEXCEPT;
template<typename _Ex>
exception_ptr make_exception_ptr(_Ex) _GLIBCXX_USE_NOEXCEPT;
/// Throw the object pointed to by the exception_ptr.
void rethrow_exception(exception_ptr) __attribute__ ((__noreturn__));
namespace __exception_ptr
{
using std::rethrow_exception;
/**
* @brief An opaque pointer to an arbitrary exception.
* @ingroup exceptions
*/
class exception_ptr
{
void* _M_exception_object;
explicit exception_ptr(void* __e) _GLIBCXX_USE_NOEXCEPT;
void _M_addref() _GLIBCXX_USE_NOEXCEPT;
void _M_release() _GLIBCXX_USE_NOEXCEPT;
void *_M_get() const _GLIBCXX_NOEXCEPT __attribute__ ((__pure__));
friend exception_ptr std::current_exception() _GLIBCXX_USE_NOEXCEPT;
friend void std::rethrow_exception(exception_ptr);
template<typename _Ex>
friend exception_ptr std::make_exception_ptr(_Ex) _GLIBCXX_USE_NOEXCEPT;
public:
exception_ptr() _GLIBCXX_USE_NOEXCEPT;
exception_ptr(const exception_ptr&) _GLIBCXX_USE_NOEXCEPT;
#if __cplusplus >= 201103L
exception_ptr(nullptr_t) noexcept
: _M_exception_object(nullptr)
{ }
exception_ptr(exception_ptr&& __o) noexcept
: _M_exception_object(__o._M_exception_object)
{ __o._M_exception_object = nullptr; }
#endif
#if (__cplusplus < 201103L) || defined (_GLIBCXX_EH_PTR_COMPAT)
typedef void (exception_ptr::*__safe_bool)();
// For construction from nullptr or 0.
exception_ptr(__safe_bool) _GLIBCXX_USE_NOEXCEPT;
#endif
exception_ptr&
operator=(const exception_ptr&) _GLIBCXX_USE_NOEXCEPT;
#if __cplusplus >= 201103L
exception_ptr&
operator=(exception_ptr&& __o) noexcept
{
exception_ptr(static_cast<exception_ptr&&>(__o)).swap(*this);
return *this;
}
#endif
~exception_ptr() _GLIBCXX_USE_NOEXCEPT;
void
swap(exception_ptr&) _GLIBCXX_USE_NOEXCEPT;
#ifdef _GLIBCXX_EH_PTR_COMPAT
// Retained for compatibility with CXXABI_1.3.
void _M_safe_bool_dummy() _GLIBCXX_USE_NOEXCEPT
__attribute__ ((__const__));
bool operator!() const _GLIBCXX_USE_NOEXCEPT
__attribute__ ((__pure__));
operator __safe_bool() const _GLIBCXX_USE_NOEXCEPT;
#endif
#if __cplusplus >= 201103L
explicit operator bool() const noexcept
{ return _M_exception_object; }
#endif
#if __cpp_impl_three_way_comparison >= 201907L \
&& ! defined _GLIBCXX_EH_PTR_RELOPS_COMPAT
friend bool
operator==(const exception_ptr&, const exception_ptr&) noexcept = default;
#else
friend _GLIBCXX_EH_PTR_USED bool
operator==(const exception_ptr& __x, const exception_ptr& __y)
_GLIBCXX_USE_NOEXCEPT
{ return __x._M_exception_object == __y._M_exception_object; }
friend _GLIBCXX_EH_PTR_USED bool
operator!=(const exception_ptr& __x, const exception_ptr& __y)
_GLIBCXX_USE_NOEXCEPT
{ return __x._M_exception_object != __y._M_exception_object; }
#endif
const class std::type_info*
__cxa_exception_type() const _GLIBCXX_USE_NOEXCEPT
__attribute__ ((__pure__));
};
_GLIBCXX_EH_PTR_USED
inline
exception_ptr::exception_ptr() _GLIBCXX_NOEXCEPT
: _M_exception_object(0)
{ }
_GLIBCXX_EH_PTR_USED
inline
exception_ptr::exception_ptr(const exception_ptr& __other) _GLIBCXX_NOEXCEPT
: _M_exception_object(__other._M_exception_object)
{
if (_M_exception_object)
_M_addref();
}
_GLIBCXX_EH_PTR_USED
inline
exception_ptr::~exception_ptr() _GLIBCXX_USE_NOEXCEPT
{
if (_M_exception_object)
_M_release();
}
_GLIBCXX_EH_PTR_USED
inline exception_ptr&
exception_ptr::operator=(const exception_ptr& __other) _GLIBCXX_USE_NOEXCEPT
{
exception_ptr(__other).swap(*this);
return *this;
}
_GLIBCXX_EH_PTR_USED
inline void
exception_ptr::swap(exception_ptr &__other) _GLIBCXX_USE_NOEXCEPT
{
void *__tmp = _M_exception_object;
_M_exception_object = __other._M_exception_object;
__other._M_exception_object = __tmp;
}
/// @relates exception_ptr
inline void
swap(exception_ptr& __lhs, exception_ptr& __rhs)
{ __lhs.swap(__rhs); }
/// @cond undocumented
template<typename _Ex>
inline void
__dest_thunk(void* __x)
{ static_cast<_Ex*>(__x)->~_Ex(); }
/// @endcond
} // namespace __exception_ptr
/// Obtain an exception_ptr pointing to a copy of the supplied object.
template<typename _Ex>
exception_ptr
make_exception_ptr(_Ex __ex) _GLIBCXX_USE_NOEXCEPT
{
#if __cpp_exceptions && __cpp_rtti && !_GLIBCXX_HAVE_CDTOR_CALLABI
void* __e = __cxxabiv1::__cxa_allocate_exception(sizeof(_Ex));
(void) __cxxabiv1::__cxa_init_primary_exception(
__e, const_cast<std::type_info*>(&typeid(__ex)),
__exception_ptr::__dest_thunk<_Ex>);
try
{
::new (__e) _Ex(__ex);
return exception_ptr(__e);
}
catch(...)
{
__cxxabiv1::__cxa_free_exception(__e);
return current_exception();
}
#elif __cpp_exceptions
try
{
throw __ex;
}
catch(...)
{
return current_exception();
}
#else // no RTTI and no exceptions
return exception_ptr();
#endif
}
#undef _GLIBCXX_EH_PTR_USED
/// @} group exceptions
} // namespace std
} // extern "C++"
#pragma GCC visibility pop
#endif
new
typeinfo
cxxabi_init_exception.h
exception_defines.h
c++config.h
std::swap
void swap(any &__x, any &__y) noexcept
Exchange the states of two any objects.
Definition: any:428
std::current_exception
exception_ptr current_exception() noexcept
std::make_exception_ptr
exception_ptr make_exception_ptr(_Ex) noexcept
Obtain an exception_ptr pointing to a copy of the supplied object.
Definition: exception_ptr.h:233
std::rethrow_exception
void rethrow_exception(exception_ptr)
Throw the object pointed to by the exception_ptr.
std
ISO C++ entities toplevel namespace is std.
std::type_info
Part of RTTI.
Definition: typeinfo:89
std::__exception_ptr::exception_ptr
An opaque pointer to an arbitrary exception.
Definition: exception_ptr.h:87