1// chrono -*- C++ -*-
2
3// Copyright (C) 2008-2015 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 <bits/c++config.h>
26#include <chrono>
27
28#ifdef _GLIBCXX_USE_C99_STDINT_TR1
29
30// Conditional inclusion of sys/time.h for gettimeofday
31#if !defined(_GLIBCXX_USE_CLOCK_MONOTONIC) && \
32    !defined(_GLIBCXX_USE_CLOCK_REALTIME) && \
33     defined(_GLIBCXX_USE_GETTIMEOFDAY)
34#include <sys/time.h>
35#endif
36
37#ifdef _GLIBCXX_USE_CLOCK_GETTIME_SYSCALL
38#include <unistd.h>
39#include <sys/syscall.h>
40#endif
41
42namespace std _GLIBCXX_VISIBILITY(default)
43{
44  namespace chrono
45  {
46  _GLIBCXX_BEGIN_NAMESPACE_VERSION
47
48    // XXX GLIBCXX_ABI Deprecated
49    inline namespace _V2 {
50
51    constexpr bool system_clock::is_steady;
52
53    system_clock::time_point
54    system_clock::now() noexcept
55    {
56#ifdef _GLIBCXX_USE_CLOCK_REALTIME
57      timespec tp;
58      // -EINVAL, -EFAULT
59#ifdef _GLIBCXX_USE_CLOCK_GETTIME_SYSCALL
60      syscall(SYS_clock_gettime, CLOCK_REALTIME, &tp);
61#else
62      clock_gettime(CLOCK_REALTIME, &tp);
63#endif
64      return time_point(duration(chrono::seconds(tp.tv_sec)
65				 + chrono::nanoseconds(tp.tv_nsec)));
66#elif defined(_GLIBCXX_USE_GETTIMEOFDAY)
67      timeval tv;
68      // EINVAL, EFAULT
69      gettimeofday(&tv, 0);
70      return time_point(duration(chrono::seconds(tv.tv_sec)
71				 + chrono::microseconds(tv.tv_usec)));
72#else
73      std::time_t __sec = std::time(0);
74      return system_clock::from_time_t(__sec);
75#endif
76    }
77
78
79    constexpr bool steady_clock::is_steady;
80
81    steady_clock::time_point
82    steady_clock::now() noexcept
83    {
84#ifdef _GLIBCXX_USE_CLOCK_MONOTONIC
85      timespec tp;
86      // -EINVAL, -EFAULT
87#ifdef _GLIBCXX_USE_CLOCK_GETTIME_SYSCALL
88      syscall(SYS_clock_gettime, CLOCK_MONOTONIC, &tp);
89#else
90      clock_gettime(CLOCK_MONOTONIC, &tp);
91#endif
92      return time_point(duration(chrono::seconds(tp.tv_sec)
93				 + chrono::nanoseconds(tp.tv_nsec)));
94#else
95      return time_point(system_clock::now().time_since_epoch());
96#endif
97    }
98
99  } // end inline namespace _V2
100
101  _GLIBCXX_END_NAMESPACE_VERSION
102  } // namespace chrono
103} // namespace std
104
105#endif // _GLIBCXX_USE_C99_STDINT_TR1
106