diff options
| -rw-r--r-- | lib/gethrxtime.c | 80 | ||||
| -rw-r--r-- | lib/gethrxtime.h | 37 | ||||
| -rw-r--r-- | lib/xtime.h | 87 | ||||
| -rw-r--r-- | m4/gethrxtime.m4 | 57 |
4 files changed, 261 insertions, 0 deletions
diff --git a/lib/gethrxtime.c b/lib/gethrxtime.c new file mode 100644 index 000000000..6f7bc098c --- /dev/null +++ b/lib/gethrxtime.c @@ -0,0 +1,80 @@ +/* gethrxtime -- get high resolution real time + + Copyright (C) 2005 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 2, or (at your option) + any later version. + + This program 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. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software Foundation, + Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ + +/* Written by Paul Eggert. */ + +#ifdef HAVE_CONFIG_H +# include <config.h> +#endif + +#include "gethrxtime.h" + +#include <sys/types.h> +#if TIME_WITH_SYS_TIME +# include <sys/time.h> +# include <time.h> +#else +# if HAVE_SYS_TIME_H +# include <sys/time.h> +# else +# include <time.h> +# endif +#endif + +/* Get the time of a high-resolution clock, preferably one that is not + subject to resetting or drifting. */ + +xtime_t +gethrxtime (void) +{ +#if HAVE_NANOUPTIME + { + struct timespec ts; + nanouptime (&ts); + return xtime_make (ts.tv_sec, ts.tv_nsec); + } +#else + +# if defined CLOCK_MONOTONIC && HAVE_CLOCK_GETTIME + { + struct timespec ts; + if (clock_gettime (CLOCK_MONOTONIC, &ts) == 0) + return xtime_make (ts.tv_sec, ts.tv_nsec); + } +# endif + +#if HAVE_MICROUPTIME + { + struct timeval tv; + microuptime (&tv); + return xtime_make (tv.tv_sec, 1000 * tv.tv_usec); + } + + /* No monotonically increasing clocks are available; fall back on a + clock that might jump backwards, since it's the best we can do. */ +# elif HAVE_GETTIMEOFDAY && XTIME_PRECISION != 1 + { + struct timeval tv; + gettimeofday (&tv, NULL); + return xtime_make (tv.tv_sec, 1000 * tv.tv_usec); + } +# else + return xtime_make (time (NULL), 0); +# endif +#endif +} diff --git a/lib/gethrxtime.h b/lib/gethrxtime.h new file mode 100644 index 000000000..2c0e36da7 --- /dev/null +++ b/lib/gethrxtime.h @@ -0,0 +1,37 @@ +/* gethrxtime -- get high resolution real time + + Copyright (C) 2005 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 2, or (at your option) + any later version. + + This program 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. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software Foundation, + Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ + +/* Written by Paul Eggert. */ + +#ifndef GETHRXTIME_H_ +#define GETHRXTIME_H_ 1 + +#include "xtime.h" + +/* Get the current time, as a count of the number of nanoseconds since + an arbitrary epoch (e.g., the system boot time). This clock can't + be set, is always increasing, and is nearly linear. */ + +#if HAVE_ARITHMETIC_HRTIME_T && HAVE_DECL_GETHRTIME +# include <time.h> +static inline xtime_t gethrxtime (void) { return gethrtime (); } +#else +xtime_t gethrxtime (void); +#endif + +#endif diff --git a/lib/xtime.h b/lib/xtime.h new file mode 100644 index 000000000..333f895b6 --- /dev/null +++ b/lib/xtime.h @@ -0,0 +1,87 @@ +/* xtime -- extended-resolution integer time stamps + + Copyright (C) 2005 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 2, or (at your option) + any later version. + + This program 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. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software Foundation, + Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ + +/* Written by Paul Eggert. */ + +#ifndef XTIME_H_ +#define XTIME_H_ 1 + +/* xtime_t is a signed type used for time stamps. It is an integer + type that is a count of nanoseconds -- except for obsolescent hosts + without sufficiently-wide integers, where it is a count of + seconds. */ +#if HAVE_LONG_LONG +typedef long long int xtime_t; +# define XTIME_PRECISION 1000000000LL +#else +# include <limits.h> +typedef long int xtime_t; +# if LONG_MAX >> 31 >> 31 == 0 +# define XTIME_PRECISION 1L +# else +# define XTIME_PRECISION 1000000000L +# endif +#endif + +/* Return an extended time value that contains S seconds and NS + nanoseconds, without any overflow checking. */ +static inline xtime_t +xtime_make (xtime_t s, int ns) +{ + if (XTIME_PRECISION == 1) + return s; + else + return XTIME_PRECISION * s + ns; +} + +/* Return the number of seconds in T, which must be nonnegative. */ +static inline xtime_t +xtime_nonnegative_sec (xtime_t t) +{ + return t / XTIME_PRECISION; +} + +/* Return the number of seconds in T. */ +static inline xtime_t +xtime_sec (xtime_t t) +{ + return (XTIME_PRECISION == 1 + ? t + : t < 0 + ? (t + XTIME_PRECISION - 1) / XTIME_PRECISION - 1 + : xtime_nonnegative_sec (t)); +} + +/* Return the number of nanoseconds in T, which must be nonnegative. */ +static inline int +xtime_nonnegative_nsec (xtime_t t) +{ + return t % XTIME_PRECISION; +} + +/* Return the number of nanoseconds in T. */ +static inline int +xtime_nsec (xtime_t t) +{ + int ns = t % XTIME_PRECISION; + if (ns < 0) + ns += XTIME_PRECISION; + return ns; +} + +#endif diff --git a/m4/gethrxtime.m4 b/m4/gethrxtime.m4 new file mode 100644 index 000000000..89c6a21e7 --- /dev/null +++ b/m4/gethrxtime.m4 @@ -0,0 +1,57 @@ +# gethrxtime.m4 serial 1 +dnl Copyright (C) 2005 Free Software Foundation, Inc. +dnl This file is free software; the Free Software Foundation +dnl gives unlimited permission to copy and/or distribute it, +dnl with or without modifications, as long as this notice is preserved. + +AC_DEFUN([gl_GETHRXTIME], +[ + AC_LIBSOURCES([gethrxtime.c, gethrxtime.h, xtime.h]) + AC_REQUIRE([gl_ARITHMETIC_HRTIME_T]) + AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS]) + AC_REQUIRE([gl_XTIME]) + AC_CHECK_DECLS([gethrtime], [], [], [#include <time.h>]) + case $ac_cv_have_decl_gethrtime,$gl_cv_arithmetic_hrtime_t in + yes,yes) ;; + *) + AC_LIBOBJ([gethrxtime]) + gl_PREREQ_GETHRXTIME;; + esac +]) + +# Test whether hrtime_t is an arithmetic type. +# It is not arithmetic in older Solaris c89 (which insists on +# not having a long long int type). +AC_DEFUN([gl_ARITHMETIC_HRTIME_T], +[ + AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS]) + AC_CACHE_CHECK([for arithmetic hrtime_t], gl_cv_arithmetic_hrtime_t, + [AC_COMPILE_IFELSE( + [AC_LANG_PROGRAM([#include <time.h>], + [hrtime_t x = 0; return x/x;])], + [gl_cv_arithmetic_hrtime_t=yes], + [gl_cv_arithmetic_hrtime_t=no])]) + if test $gl_cv_arithmetic_hrtime_t = yes; then + AC_DEFINE([HAVE_ARITHMETIC_HRTIME_T], 1, + [Define if you have an arithmetic hrtime_t type.]) + fi +]) + +# Prerequisites of lib/xtime.h. +AC_DEFUN([gl_XTIME], +[ + AC_REQUIRE([AC_C_INLINE]) + AC_REQUIRE([gl_AC_TYPE_LONG_LONG]) + : +]) + +# Prerequisites of lib/gethrxtime.c. +AC_DEFUN([gl_PREREQ_GETHRXTIME], +[ + dnl Do not AC_REQUIRE([gl_CLOCK_TIME]), since that would unnecessarily + dnl require -lrt on Solaris. Invocations of clock_gettime should be + dnl safe in gethrxtime.c since Solaris has native gethrtime. + AC_REQUIRE([AC_HEADER_TIME]) + AC_CHECK_FUNCS_ONCE(gettimeofday microuptime nanouptime) + : +]) |