3 dnl Copyright (C) 2007, 2009-2024 Free Software Foundation, Inc.
4 dnl This file is free software; the Free Software Foundation
5 dnl gives unlimited permission to copy and/or distribute it,
6 dnl with or without modifications, as long as this notice is preserved.
8 # Configure a replacement for <sys/time.h>.
10 # Written by Paul Eggert and Martin Lambers.
12 AC_DEFUN_ONCE([gl_SYS_TIME_H],
14 dnl Use AC_REQUIRE here, so that the REPLACE_GETTIMEOFDAY=0 statement
15 dnl below is expanded once only, before all REPLACE_GETTIMEOFDAY=1
16 dnl statements that occur in other macros.
17 AC_REQUIRE([gl_SYS_TIME_H_DEFAULTS])
18 AC_REQUIRE([AC_C_RESTRICT])
19 AC_CHECK_HEADERS_ONCE([sys/time.h])
20 gl_CHECK_NEXT_HEADERS([sys/time.h])
22 if test $ac_cv_header_sys_time_h != yes; then
26 dnl On native Windows with MSVC, 'struct timeval' is defined in <winsock2.h>
27 dnl only. So include that header in the list.
28 gl_PREREQ_SYS_H_WINSOCK2
29 AC_CACHE_CHECK([for struct timeval], [gl_cv_sys_struct_timeval],
37 # include <winsock2.h>
40 [[static struct timeval x; x.tv_sec = x.tv_usec;]])],
41 [gl_cv_sys_struct_timeval=yes],
42 [gl_cv_sys_struct_timeval=no])
44 if test $gl_cv_sys_struct_timeval != yes; then
47 dnl On native Windows with a 64-bit 'time_t', 'struct timeval' is defined
48 dnl (in <sys/time.h> and <winsock2.h> for mingw64, in <winsock2.h> only
49 dnl for MSVC) with a tv_sec field of type 'long' (32-bit!), which is
50 dnl smaller than the 'time_t' type mandated by POSIX.
51 dnl On OpenBSD 5.1 amd64, tv_sec is 64 bits and time_t 32 bits, but
52 dnl that is good enough.
53 AC_CACHE_CHECK([for wide-enough struct timeval.tv_sec member],
54 [gl_cv_sys_struct_timeval_tv_sec],
62 # include <winsock2.h>
65 [[static struct timeval x;
66 typedef int verify_tv_sec_type[
67 sizeof (time_t) <= sizeof x.tv_sec ? 1 : -1
70 [gl_cv_sys_struct_timeval_tv_sec=yes],
71 [gl_cv_sys_struct_timeval_tv_sec=no])
73 if test $gl_cv_sys_struct_timeval_tv_sec != yes; then
74 REPLACE_STRUCT_TIMEVAL=1
78 dnl Check for declarations of anything we want to poison if the
79 dnl corresponding gnulib module is not in use.
80 gl_WARN_ON_USE_PREPARE([[
82 # include <sys/time.h>
88 # gl_SYS_TIME_MODULE_INDICATOR([modulename])
89 # sets the shell variable that indicates the presence of the given module
90 # to a C preprocessor expression that will evaluate to 1.
91 # This macro invocation must not occur in macros that are AC_REQUIREd.
92 AC_DEFUN([gl_SYS_TIME_MODULE_INDICATOR],
94 dnl Ensure to expand the default settings once only.
95 gl_SYS_TIME_H_REQUIRE_DEFAULTS
96 gl_MODULE_INDICATOR_SET_VARIABLE([$1])
97 dnl Define it also as a C macro, for the benefit of the unit tests.
98 gl_MODULE_INDICATOR_FOR_TESTS([$1])
101 # Initializes the default values for AC_SUBSTed shell variables.
102 # This macro must not be AC_REQUIREd. It must only be invoked, and only
103 # outside of macros or in macros that are not AC_REQUIREd.
104 AC_DEFUN([gl_SYS_TIME_H_REQUIRE_DEFAULTS],
106 m4_defun(GL_MODULE_INDICATOR_PREFIX[_SYS_TIME_H_MODULE_INDICATOR_DEFAULTS], [
107 gl_MODULE_INDICATOR_INIT_VARIABLE([GNULIB_GETTIMEOFDAY])
109 m4_require(GL_MODULE_INDICATOR_PREFIX[_SYS_TIME_H_MODULE_INDICATOR_DEFAULTS])
110 AC_REQUIRE([gl_SYS_TIME_H_DEFAULTS])
113 AC_DEFUN([gl_SYS_TIME_H_DEFAULTS],
115 dnl Assume POSIX behavior unless another module says otherwise.
116 HAVE_GETTIMEOFDAY=1; AC_SUBST([HAVE_GETTIMEOFDAY])
117 HAVE_STRUCT_TIMEVAL=1; AC_SUBST([HAVE_STRUCT_TIMEVAL])
118 HAVE_SYS_TIME_H=1; AC_SUBST([HAVE_SYS_TIME_H])
119 REPLACE_GETTIMEOFDAY=0; AC_SUBST([REPLACE_GETTIMEOFDAY])
120 REPLACE_STRUCT_TIMEVAL=0; AC_SUBST([REPLACE_STRUCT_TIMEVAL])