| // Nested Exception support header (nested_exception class) for -*- C++ -*- |
| |
| // Copyright (C) 2009, 2010, 2011 Free Software Foundation, Inc. |
| // |
| // This file is part of the GNU ISO C++ Library. This library 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. |
| |
| // This library 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/nested_exception.h |
| * This is an internal header file, included by other library headers. |
| * Do not attempt to use it directly. @headername{exception} |
| */ |
| |
| #ifndef _GLIBCXX_NESTED_EXCEPTION_H |
| #define _GLIBCXX_NESTED_EXCEPTION_H 1 |
| |
| #pragma GCC visibility push(default) |
| |
| #ifndef __GXX_EXPERIMENTAL_CXX0X__ |
| # include <bits/c++0x_warning.h> |
| #else |
| |
| #include <bits/c++config.h> |
| |
| #if !defined(_GLIBCXX_ATOMIC_BUILTINS_4) |
| # error This platform does not support exception propagation. |
| #endif |
| |
| extern "C++" { |
| |
| namespace std |
| { |
| /** |
| * @addtogroup exceptions |
| * @{ |
| */ |
| |
| /// Exception class with exception_ptr data member. |
| class nested_exception |
| { |
| exception_ptr _M_ptr; |
| |
| public: |
| nested_exception() throw() : _M_ptr(current_exception()) { } |
| |
| nested_exception(const nested_exception&) = default; |
| |
| nested_exception& operator=(const nested_exception&) = default; |
| |
| virtual ~nested_exception(); |
| |
| void |
| rethrow_nested() const __attribute__ ((__noreturn__)) |
| { rethrow_exception(_M_ptr); } |
| |
| exception_ptr |
| nested_ptr() const |
| { return _M_ptr; } |
| }; |
| |
| template<typename _Except> |
| struct _Nested_exception : public _Except, public nested_exception |
| { |
| explicit _Nested_exception(_Except&& __ex) |
| : _Except(static_cast<_Except&&>(__ex)) |
| { } |
| }; |
| |
| template<typename _Ex> |
| struct __get_nested_helper |
| { |
| static const nested_exception* |
| _S_get(const _Ex& __ex) |
| { return dynamic_cast<const nested_exception*>(&__ex); } |
| }; |
| |
| template<typename _Ex> |
| struct __get_nested_helper<_Ex*> |
| { |
| static const nested_exception* |
| _S_get(const _Ex* __ex) |
| { return dynamic_cast<const nested_exception*>(__ex); } |
| }; |
| |
| template<typename _Ex> |
| inline const nested_exception* |
| __get_nested_exception(const _Ex& __ex) |
| { return __get_nested_helper<_Ex>::_S_get(__ex); } |
| |
| template<typename _Ex> |
| void |
| __throw_with_nested(_Ex&&, const nested_exception* = 0) |
| __attribute__ ((__noreturn__)); |
| |
| template<typename _Ex> |
| void |
| __throw_with_nested(_Ex&&, ...) __attribute__ ((__noreturn__)); |
| |
| // This function should never be called, but is needed to avoid a warning |
| // about ambiguous base classes when instantiating throw_with_nested<_Ex>() |
| // with a type that has an accessible nested_exception base. |
| template<typename _Ex> |
| inline void |
| __throw_with_nested(_Ex&& __ex, const nested_exception*) |
| { throw __ex; } |
| |
| template<typename _Ex> |
| inline void |
| __throw_with_nested(_Ex&& __ex, ...) |
| { throw _Nested_exception<_Ex>(static_cast<_Ex&&>(__ex)); } |
| |
| template<typename _Ex> |
| void |
| throw_with_nested(_Ex __ex) __attribute__ ((__noreturn__)); |
| |
| /// If @p __ex is derived from nested_exception, @p __ex. |
| /// Else, an implementation-defined object derived from both. |
| template<typename _Ex> |
| inline void |
| throw_with_nested(_Ex __ex) |
| { |
| if (__get_nested_exception(__ex)) |
| throw __ex; |
| __throw_with_nested(static_cast<_Ex&&>(__ex), &__ex); |
| } |
| |
| /// If @p __ex is derived from nested_exception, @p __ex.rethrow_nested(). |
| template<typename _Ex> |
| inline void |
| rethrow_if_nested(const _Ex& __ex) |
| { |
| if (const nested_exception* __nested = __get_nested_exception(__ex)) |
| __nested->rethrow_nested(); |
| } |
| |
| /// Overload, See N2619 |
| inline void |
| rethrow_if_nested(const nested_exception& __ex) |
| { __ex.rethrow_nested(); } |
| |
| // @} group exceptions |
| } // namespace std |
| |
| } // extern "C++" |
| |
| #endif // __GXX_EXPERIMENTAL_CXX0X__ |
| |
| #pragma GCC visibility pop |
| |
| #endif // _GLIBCXX_NESTED_EXCEPTION_H |