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authorAnas Nashif <anas.nashif@intel.com>2012-11-05 11:10:13 -0800
committerAnas Nashif <anas.nashif@intel.com>2012-11-05 11:10:13 -0800
commit7be93f2d05131d061bd4790ae33c8d50f50010d7 (patch)
tree72736c1606f803a92ffa07c9808ffea2521d009e /m4/gettimeofday.m4
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Imported Upstream version 1.4.16upstream/1.4.16
Diffstat (limited to 'm4/gettimeofday.m4')
-rw-r--r--m4/gettimeofday.m4120
1 files changed, 120 insertions, 0 deletions
diff --git a/m4/gettimeofday.m4 b/m4/gettimeofday.m4
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+# serial 15
+
+# Copyright (C) 2001-2003, 2005, 2007, 2009-2011 Free Software Foundation, Inc.
+# This file is free software; the Free Software Foundation
+# gives unlimited permission to copy and/or distribute it,
+# with or without modifications, as long as this notice is preserved.
+
+dnl From Jim Meyering.
+
+AC_DEFUN([gl_FUNC_GETTIMEOFDAY],
+[
+ AC_REQUIRE([AC_C_RESTRICT])
+ AC_REQUIRE([gl_HEADER_SYS_TIME_H])
+ AC_REQUIRE([gl_HEADER_SYS_TIME_H_DEFAULTS])
+ AC_CHECK_FUNCS_ONCE([gettimeofday])
+
+ gl_gettimeofday_timezone=void
+ if test $ac_cv_func_gettimeofday != yes; then
+ HAVE_GETTIMEOFDAY=0
+ AC_LIBOBJ([gettimeofday])
+ gl_PREREQ_GETTIMEOFDAY
+ else
+ gl_FUNC_GETTIMEOFDAY_CLOBBER
+ AC_CACHE_CHECK([for gettimeofday with POSIX signature],
+ [gl_cv_func_gettimeofday_posix_signature],
+ [AC_COMPILE_IFELSE(
+ [AC_LANG_PROGRAM(
+ [[#include <sys/time.h>
+ struct timeval c;
+ int gettimeofday (struct timeval *restrict, void *restrict);
+ ]],
+ [[/* glibc uses struct timezone * rather than the POSIX void *
+ if _GNU_SOURCE is defined. However, since the only portable
+ use of gettimeofday uses NULL as the second parameter, and
+ since the glibc definition is actually more typesafe, it is
+ not worth wrapping this to get a compliant signature. */
+ int (*f) (struct timeval *restrict, void *restrict)
+ = gettimeofday;
+ int x = f (&c, 0);
+ return !(x | c.tv_sec | c.tv_usec);
+ ]])],
+ [gl_cv_func_gettimeofday_posix_signature=yes],
+ [AC_COMPILE_IFELSE(
+ [AC_LANG_PROGRAM(
+ [[#include <sys/time.h>
+int gettimeofday (struct timeval *restrict, struct timezone *restrict);
+ ]])],
+ [gl_cv_func_gettimeofday_posix_signature=almost],
+ [gl_cv_func_gettimeofday_posix_signature=no])])])
+ if test $gl_cv_func_gettimeofday_posix_signature = almost; then
+ gl_gettimeofday_timezone='struct timezone'
+ elif test $gl_cv_func_gettimeofday_posix_signature != yes; then
+ REPLACE_GETTIMEOFDAY=1
+ AC_LIBOBJ([gettimeofday])
+ gl_PREREQ_GETTIMEOFDAY
+ fi
+ fi
+ AC_DEFINE_UNQUOTED([GETTIMEOFDAY_TIMEZONE], [$gl_gettimeofday_timezone],
+ [Define this to 'void' or 'struct timezone' to match the system's
+ declaration of the second argument to gettimeofday.])
+])
+
+
+dnl See if gettimeofday clobbers the static buffer that localtime uses
+dnl for its return value. The gettimeofday function from Mac OS X 10.0.4
+dnl (i.e., Darwin 1.3.7) has this problem.
+dnl
+dnl If it does, then arrange to use gettimeofday and localtime only via
+dnl the wrapper functions that work around the problem.
+
+AC_DEFUN([gl_FUNC_GETTIMEOFDAY_CLOBBER],
+[
+ AC_REQUIRE([gl_HEADER_SYS_TIME_H])
+
+ AC_CACHE_CHECK([whether gettimeofday clobbers localtime buffer],
+ [gl_cv_func_gettimeofday_clobber],
+ [AC_RUN_IFELSE(
+ [AC_LANG_PROGRAM(
+ [[#include <string.h>
+ #include <sys/time.h>
+ #include <time.h>
+ #include <stdlib.h>
+ ]],
+ [[
+ time_t t = 0;
+ struct tm *lt;
+ struct tm saved_lt;
+ struct timeval tv;
+ lt = localtime (&t);
+ saved_lt = *lt;
+ gettimeofday (&tv, NULL);
+ return memcmp (lt, &saved_lt, sizeof (struct tm)) != 0;
+ ]])],
+ [gl_cv_func_gettimeofday_clobber=no],
+ [gl_cv_func_gettimeofday_clobber=yes],
+ dnl When crosscompiling, assume it is broken.
+ [gl_cv_func_gettimeofday_clobber=yes])])
+
+ if test $gl_cv_func_gettimeofday_clobber = yes; then
+ REPLACE_GETTIMEOFDAY=1
+ gl_GETTIMEOFDAY_REPLACE_LOCALTIME
+ AC_DEFINE([GETTIMEOFDAY_CLOBBERS_LOCALTIME], [1],
+ [Define if gettimeofday clobbers the localtime buffer.])
+ fi
+])
+
+AC_DEFUN([gl_GETTIMEOFDAY_REPLACE_LOCALTIME], [
+ AC_LIBOBJ([gettimeofday])
+ gl_PREREQ_GETTIMEOFDAY
+ AC_DEFINE([gmtime], [rpl_gmtime],
+ [Define to rpl_gmtime if the replacement function should be used.])
+ AC_DEFINE([localtime], [rpl_localtime],
+ [Define to rpl_localtime if the replacement function should be used.])
+])
+
+# Prerequisites of lib/gettimeofday.c.
+AC_DEFUN([gl_PREREQ_GETTIMEOFDAY], [
+ AC_CHECK_HEADERS([sys/timeb.h])
+ AC_CHECK_FUNCS([_ftime])
+])