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+# serial 29
+
+# Copyright (C) 2001-2003, 2005, 2007, 2009-2022 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([gl_SYS_TIME_H_DEFAULTS])
+ AC_REQUIRE([AC_C_RESTRICT])
+ AC_REQUIRE([AC_CANONICAL_HOST])
+ AC_REQUIRE([gl_SYS_TIME_H])
+ AC_CHECK_FUNCS_ONCE([gettimeofday])
+
+ gl_gettimeofday_timezone=void
+ if test $ac_cv_func_gettimeofday != yes; then
+ HAVE_GETTIMEOFDAY=0
+ else
+ 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
+ fi
+ dnl If we override 'struct timeval', we also have to override gettimeofday.
+ if test $REPLACE_STRUCT_TIMEVAL = 1; then
+ REPLACE_GETTIMEOFDAY=1
+ fi
+ dnl On mingw, the original gettimeofday has only a precision of 15.6
+ dnl milliseconds. So override it.
+ case "$host_os" in
+ mingw*) REPLACE_GETTIMEOFDAY=1 ;;
+ esac
+ 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.])
+])
+
+# Prerequisites of lib/gettimeofday.c.
+AC_DEFUN([gl_PREREQ_GETTIMEOFDAY], [:])