1 /* -*- buffer-read-only: t -*- vi: set ro: */
2 /* DO NOT EDIT! GENERATED AUTOMATICALLY! */
3 /* timespec -- System time interface
5 Copyright (C) 2000, 2002, 2004-2005, 2007, 2009-2013 Free Software
8 This program is free software: you can redistribute it and/or modify
9 it under the terms of the GNU General Public License as published by
10 the Free Software Foundation; either version 3 of the License, or
11 (at your option) any later version.
13 This program is distributed in the hope that it will be useful,
14 but WITHOUT ANY WARRANTY; without even the implied warranty of
15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 GNU General Public License for more details.
18 You should have received a copy of the GNU General Public License
19 along with this program. If not, see <http://www.gnu.org/licenses/>. */
21 #if ! defined TIMESPEC_H
26 _GL_INLINE_HEADER_BEGIN
27 #ifndef _GL_TIMESPEC_INLINE
28 # define _GL_TIMESPEC_INLINE _GL_INLINE
31 /* Return negative, zero, positive if A < B, A == B, A > B, respectively.
33 For each time stamp T, this code assumes that either:
35 * T.tv_nsec is in the range 0..999999999; or
36 * T.tv_sec corresponds to a valid leap second on a host that supports
37 leap seconds, and T.tv_nsec is in the range 1000000000..1999999999; or
38 * T.tv_sec is the minimum time_t value and T.tv_nsec is -1; or
39 T.tv_sec is the maximum time_t value and T.tv_nsec is 2000000000.
40 This allows for special struct timespec values that are less or
41 greater than all possible valid time stamps.
43 In all these cases, it is safe to subtract two tv_nsec values and
44 convert the result to integer without worrying about overflow on
45 any platform of interest to the GNU project, since all such
46 platforms have 32-bit int or wider.
48 Replacing "(int) (a.tv_nsec - b.tv_nsec)" with something like
49 "a.tv_nsec < b.tv_nsec ? -1 : a.tv_nsec > b.tv_nsec" would cause
50 this function to work in some cases where the above assumption is
51 violated, but not in all cases (e.g., a.tv_sec==1, a.tv_nsec==-2,
52 b.tv_sec==0, b.tv_nsec==999999999) and is arguably not worth the
53 extra instructions. Using a subtraction has the advantage of
54 detecting some invalid cases on platforms that detect integer
57 The (int) cast avoids a gcc -Wconversion warning. */
59 _GL_TIMESPEC_INLINE int
60 timespec_cmp (struct timespec a, struct timespec b)
62 return (a.tv_sec < b.tv_sec ? -1
63 : a.tv_sec > b.tv_sec ? 1
64 : (int) (a.tv_nsec - b.tv_nsec));
67 /* Return -1, 0, 1, depending on the sign of A. A.tv_nsec must be
69 _GL_TIMESPEC_INLINE int
70 timespec_sign (struct timespec a)
72 return a.tv_sec < 0 ? -1 : a.tv_sec || a.tv_nsec;
75 struct timespec timespec_add (struct timespec, struct timespec)
77 struct timespec timespec_sub (struct timespec, struct timespec)
79 struct timespec dtotimespec (double)
82 /* Return an approximation to A, of type 'double'. */
83 _GL_TIMESPEC_INLINE double
84 timespectod (struct timespec a)
86 return a.tv_sec + a.tv_nsec / 1e9;
89 void gettime (struct timespec *);
90 int settime (struct timespec const *);