1 // future -*- C++ -*-
2 
3 // Copyright (C) 2009-2015 Free Software Foundation, Inc.
4 //
5 // This file is part of the GNU ISO C++ Library.  This library is free
6 // software; you can redistribute it and/or modify it under the
7 // terms of the GNU General Public License as published by the
8 // Free Software Foundation; either version 3, or (at your option)
9 // any later version.
10 
11 // This library is distributed in the hope that it will be useful,
12 // but WITHOUT ANY WARRANTY; without even the implied warranty of
13 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14 // GNU General Public License for more details.
15 
16 // Under Section 7 of GPL version 3, you are granted additional
17 // permissions described in the GCC Runtime Library Exception, version
18 // 3.1, as published by the Free Software Foundation.
19 
20 // You should have received a copy of the GNU General Public License and
21 // a copy of the GCC Runtime Library Exception along with this program;
22 // see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
23 // <http://www.gnu.org/licenses/>.
24 
25 #include <future>
26 
27 namespace
28 {
29   struct future_error_category : public std::error_category
30   {
31     virtual const char*
name__anonf1a334dd0111::future_error_category32     name() const noexcept
33     { return "future"; }
34 
35     _GLIBCXX_DEFAULT_ABI_TAG
message__anonf1a334dd0111::future_error_category36     virtual std::string message(int __ec) const
37     {
38       std::string __msg;
39       switch (std::future_errc(__ec))
40       {
41       case std::future_errc::broken_promise:
42           __msg = "Broken promise";
43           break;
44       case std::future_errc::future_already_retrieved:
45           __msg = "Future already retrieved";
46           break;
47       case std::future_errc::promise_already_satisfied:
48           __msg = "Promise already satisfied";
49           break;
50       case std::future_errc::no_state:
51           __msg = "No associated state";
52           break;
53       default:
54           __msg = "Unknown error";
55           break;
56       }
57       return __msg;
58     }
59   };
60 
61   const future_error_category&
__future_category_instance()62   __future_category_instance() noexcept
63   {
64     static const future_error_category __fec{};
65     return __fec;
66   }
67 }
68 
69 namespace std _GLIBCXX_VISIBILITY(default)
70 {
71 _GLIBCXX_BEGIN_NAMESPACE_VERSION
72 
future_category()73   const error_category& future_category() noexcept
74   { return __future_category_instance(); }
75 
~future_error()76   future_error::~future_error() noexcept { }
77 
78   const char*
what() const79   future_error::what() const noexcept { return logic_error::what(); }
80 
81 #if defined(_GLIBCXX_HAS_GTHREADS) && defined(_GLIBCXX_USE_C99_STDINT_TR1) \
82   && (ATOMIC_INT_LOCK_FREE > 1)
83   __future_base::_Result_base::_Result_base() = default;
84 
85   __future_base::_Result_base::~_Result_base() = default;
86 
87   void
_S_run(void * p)88   __future_base::_State_baseV2::_Make_ready::_S_run(void* p)
89   {
90     unique_ptr<_Make_ready> mr{static_cast<_Make_ready*>(p)};
91     if (auto state = mr->_M_shared_state.lock())
92       {
93 	// Use release MO to synchronize with observers of the ready state.
94 	state->_M_status._M_store_notify_all(_Status::__ready,
95 	    memory_order_release);
96       }
97   }
98 
99   // defined in src/c++11/condition_variable.cc
100   extern void
101   __at_thread_exit(__at_thread_exit_elt* elt);
102 
103   void
_M_set()104   __future_base::_State_baseV2::_Make_ready::_M_set()
105   {
106     _M_cb = &_Make_ready::_S_run;
107     __at_thread_exit(this);
108   }
109 #endif
110 
111 _GLIBCXX_END_NAMESPACE_VERSION
112 } // namespace std
113