Mercurial > hg > octave-lyh > gnulib-hg
changeset 859:151259bd1f64
(AM_FUNC_MKTIME): Fix bug in mktime test -- don't
test now, test a couple of thousand times.
author | Jim Meyering <jim@meyering.net> |
---|---|
date | Wed, 22 Jan 1997 22:38:37 +0000 |
parents | d6b1cfa29509 |
children | 68da68da125e |
files | m4/mktime.m4 |
diffstat | 1 files changed, 26 insertions(+), 4 deletions(-) [+] |
line wrap: on
line diff
--- a/m4/mktime.m4 +++ b/m4/mktime.m4 @@ -5,7 +5,8 @@ [AC_REQUIRE([AC_HEADER_TIME])dnl AC_CHECK_HEADERS(sys/time.h) AC_CACHE_CHECK([for working mktime], am_cv_func_working_mktime, - [AC_TRY_RUN([/* Test program from Tony Leneis (tony@plaza.ds.adp.com). */ + [AC_TRY_RUN([/* Test program from Paul Eggert (eggert@twinsun.com) + and Tony Leneis (tony@plaza.ds.adp.com). */ #if TIME_WITH_SYS_TIME # include <sys/time.h> # include <time.h> @@ -16,12 +17,33 @@ # include <time.h> # endif #endif + +static time_t time_t_max; + +static void +mktime_test (now) + time_t now; +{ + if (mktime (localtime (&now)) != now) + exit (1); + now = time_t_max - now; + if (mktime (localtime (&now)) != now) + exit (1); +} + int main () { - time_t today = time (0); - struct tm *local = localtime (&today); - exit (mktime (local) != today); + time_t t, delta; + for (time_t_max = 1; 0 < time_t_max; time_t_max *= 2) + continue; + time_t_max--; + delta = time_t_max / 997; /* a suitable prime number */ + for (t = 0; t <= time_t_max - delta; t += delta) + mktime_test (t); + mktime_test ((time_t) 60 * 60); + mktime_test ((time_t) 60 * 60 * 24); + exit (0); } ], am_cv_func_working_mktime=yes, am_cv_func_working_mktime=no,