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author | Stefan Monnier <monnier@iro.umontreal.ca> | 2022-09-25 16:15:16 -0400 |
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committer | Stefan Monnier <monnier@iro.umontreal.ca> | 2022-09-25 16:15:16 -0400 |
commit | 650c20f1ca4e07591a727e1cfcc74b3363d15985 (patch) | |
tree | 85d11f6437cde22f410c25e0e5f71a3131ebd07d /lib/timespec.h | |
parent | 8869332684c2302b5ba1ead4568bbc7ba1c0183e (diff) | |
parent | 4b85ae6a24380fb67a3315eaec9233f17a872473 (diff) | |
download | emacs-650c20f1ca4e07591a727e1cfcc74b3363d15985.tar.gz emacs-650c20f1ca4e07591a727e1cfcc74b3363d15985.tar.bz2 emacs-650c20f1ca4e07591a727e1cfcc74b3363d15985.zip |
Merge 'master' into noverlay
Diffstat (limited to 'lib/timespec.h')
-rw-r--r-- | lib/timespec.h | 76 |
1 files changed, 29 insertions, 47 deletions
diff --git a/lib/timespec.h b/lib/timespec.h index 3831301578e..9e358289a2a 100644 --- a/lib/timespec.h +++ b/lib/timespec.h @@ -1,25 +1,25 @@ /* timespec -- System time interface - Copyright (C) 2000, 2002, 2004-2005, 2007, 2009-2017 Free Software + Copyright (C) 2000, 2002, 2004-2005, 2007, 2009-2022 Free Software Foundation, Inc. - This program 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 of the License, or - (at your option) any later version. + This file is free software: you can redistribute it and/or modify + it under the terms of the GNU Lesser General Public License as + published by the Free Software Foundation, either version 3 of the + License, or (at your option) any later version. - This program is distributed in the hope that it will be useful, + This file 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. + GNU Lesser General Public License for more details. - You should have received a copy of the GNU General Public License + You should have received a copy of the GNU Lesser General Public License along with this program. If not, see <https://www.gnu.org/licenses/>. */ #if ! defined TIMESPEC_H -# define TIMESPEC_H +#define TIMESPEC_H -# include <time.h> +#include <time.h> #ifndef _GL_INLINE_HEADER_BEGIN #error "Please include config.h first." @@ -33,11 +33,19 @@ _GL_INLINE_HEADER_BEGIN extern "C" { #endif -/* Resolution of timespec timestamps (in units per second), and log - base 10 of the resolution. */ +#include "arg-nonnull.h" -enum { TIMESPEC_RESOLUTION = 1000000000 }; -enum { LOG10_TIMESPEC_RESOLUTION = 9 }; +/* Inverse resolution of timespec timestamps (in units per second), + and log base 10 of the inverse resolution. */ + +enum { TIMESPEC_HZ = 1000000000 }; +enum { LOG10_TIMESPEC_HZ = 9 }; + +/* Obsolescent names for backward compatibility. + They are misnomers, because TIMESPEC_RESOLUTION is not a resolution. */ + +enum { TIMESPEC_RESOLUTION = TIMESPEC_HZ }; +enum { LOG10_TIMESPEC_RESOLUTION = LOG10_TIMESPEC_HZ }; /* Return a timespec with seconds S and nanoseconds NS. */ @@ -50,40 +58,12 @@ make_timespec (time_t s, long int ns) return r; } -/* Return negative, zero, positive if A < B, A == B, A > B, respectively. - - For each timestamp T, this code assumes that either: - - * T.tv_nsec is in the range 0..999999999; or - * T.tv_sec corresponds to a valid leap second on a host that supports - leap seconds, and T.tv_nsec is in the range 1000000000..1999999999; or - * T.tv_sec is the minimum time_t value and T.tv_nsec is -1; or - T.tv_sec is the maximum time_t value and T.tv_nsec is 2000000000. - This allows for special struct timespec values that are less or - greater than all possible valid timestamps. - - In all these cases, it is safe to subtract two tv_nsec values and - convert the result to integer without worrying about overflow on - any platform of interest to the GNU project, since all such - platforms have 32-bit int or wider. - - Replacing "(int) (a.tv_nsec - b.tv_nsec)" with something like - "a.tv_nsec < b.tv_nsec ? -1 : a.tv_nsec > b.tv_nsec" would cause - this function to work in some cases where the above assumption is - violated, but not in all cases (e.g., a.tv_sec==1, a.tv_nsec==-2, - b.tv_sec==0, b.tv_nsec==999999999) and is arguably not worth the - extra instructions. Using a subtraction has the advantage of - detecting some invalid cases on platforms that detect integer - overflow. - - The (int) cast avoids a gcc -Wconversion warning. */ +/* Return negative, zero, positive if A < B, A == B, A > B, respectively. */ _GL_TIMESPEC_INLINE int _GL_ATTRIBUTE_PURE timespec_cmp (struct timespec a, struct timespec b) { - return (a.tv_sec < b.tv_sec ? -1 - : a.tv_sec > b.tv_sec ? 1 - : (int) (a.tv_nsec - b.tv_nsec)); + return 2 * _GL_CMP (a.tv_sec, b.tv_sec) + _GL_CMP (a.tv_nsec, b.tv_nsec); } /* Return -1, 0, 1, depending on the sign of A. A.tv_nsec must be @@ -91,7 +71,7 @@ timespec_cmp (struct timespec a, struct timespec b) _GL_TIMESPEC_INLINE int _GL_ATTRIBUTE_PURE timespec_sign (struct timespec a) { - return a.tv_sec < 0 ? -1 : a.tv_sec || a.tv_nsec; + return _GL_CMP (a.tv_sec, 0) + (!a.tv_sec & !!a.tv_nsec); } struct timespec timespec_add (struct timespec, struct timespec) @@ -108,8 +88,10 @@ timespectod (struct timespec a) return a.tv_sec + a.tv_nsec / 1e9; } -void gettime (struct timespec *); -int settime (struct timespec const *); +long int gettime_res (void); +struct timespec current_timespec (void); +void gettime (struct timespec *) _GL_ARG_NONNULL ((1)); +int settime (struct timespec const *) _GL_ARG_NONNULL ((1)); #ifdef __cplusplus } |