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authorStefan Monnier <monnier@iro.umontreal.ca>2022-09-25 16:15:16 -0400
committerStefan Monnier <monnier@iro.umontreal.ca>2022-09-25 16:15:16 -0400
commit650c20f1ca4e07591a727e1cfcc74b3363d15985 (patch)
tree85d11f6437cde22f410c25e0e5f71a3131ebd07d /lib/timespec.h
parent8869332684c2302b5ba1ead4568bbc7ba1c0183e (diff)
parent4b85ae6a24380fb67a3315eaec9233f17a872473 (diff)
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Merge 'master' into noverlay
Diffstat (limited to 'lib/timespec.h')
-rw-r--r--lib/timespec.h76
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
}