Merge commit 'a39d4083cab589d7cd6a13e8a4b8db8875261d75'

[gnulib.git] / m4 / gettimeofday.m4

diff --git a/m4/gettimeofday.m4 b/m4/gettimeofday.m4
index 836a4b9..1c2d66e 100644 (file)
--- a/m4/gettimeofday.m4
+++ b/m4/gettimeofday.m4
@@ -1,75 +1,138 @@
-#serial 3
+# serial 21
+
+# Copyright (C) 2001-2003, 2005, 2007, 2009-2014 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.
 
 dnl From Jim Meyering.

-dnl
+
+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
+  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
+    fi
+    dnl If we override 'struct timeval', we also have to override gettimeofday.
+    if test $REPLACE_STRUCT_TIMEVAL = 1; then
+      REPLACE_GETTIMEOFDAY=1
+    fi
+    m4_ifdef([gl_FUNC_TZSET_CLOBBER], [
+      gl_FUNC_TZSET_CLOBBER
+      case "$gl_cv_func_tzset_clobber" in
+        *yes)
+          REPLACE_GETTIMEOFDAY=1
+          gl_GETTIMEOFDAY_REPLACE_LOCALTIME
+          AC_DEFINE([tzset], [rpl_tzset],
+            [Define to rpl_tzset if the wrapper function should be used.])
+          AC_DEFINE([TZSET_CLOBBERS_LOCALTIME], [1],
+            [Define if tzset clobbers localtime's static buffer.])
+          ;;
+      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.])
+])
+
+

 dnl See if gettimeofday clobbers the static buffer that localtime uses
 dnl See if gettimeofday clobbers the static buffer that localtime uses

-dnl for it's return value.  The gettimeofday function from Mac OS X 10.0.4,
-dnl i.e. Darwin 1.3.7 has this problem.
+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.
 
 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([AC_FUNC_GETTIMEOFDAY_CLOBBER],
+AC_DEFUN([gl_FUNC_GETTIMEOFDAY_CLOBBER],

 [
 [

- AC_REQUIRE([AC_HEADER_TIME])
- AC_CHECK_HEADERS_ONCE(stdlib.h string.h)
- AC_CACHE_CHECK([whether gettimeofday clobbers localtime buffer],
-  jm_cv_func_gettimeofday_clobber,
-  [AC_TRY_RUN([
-#include <stdio.h>
-#if HAVE_STRING_H
-# include <string.h>
-#endif
-
-#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
+ AC_REQUIRE([gl_HEADER_SYS_TIME_H])
+ AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles

 
 

-#if HAVE_STDLIB_H
-# include <stdlib.h>
-#endif
+ 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],
+     [# When cross-compiling:
+      case "$host_os" in
+                # Guess all is fine on glibc systems.
+        *-gnu*) gl_cv_func_gettimeofday_clobber="guessing no" ;;
+                # If we don't know, assume the worst.
+        *)      gl_cv_func_gettimeofday_clobber="guessing yes" ;;
+      esac
+     ])])

 
 

-int
-main ()
-{
-  time_t t = 0;
-  struct tm *lt;
-  struct tm saved_lt;
-  struct timeval tv;
-  lt = localtime (&t);
-  saved_lt = *lt;
-  gettimeofday (&tv, NULL);
-  if (memcmp (lt, &saved_lt, sizeof (struct tm)) != 0)
-    exit (1);
+ case "$gl_cv_func_gettimeofday_clobber" in
+   *yes)
+     REPLACE_GETTIMEOFDAY=1
+     gl_GETTIMEOFDAY_REPLACE_LOCALTIME
+     AC_DEFINE([GETTIMEOFDAY_CLOBBERS_LOCALTIME], [1],
+       [Define if gettimeofday clobbers the localtime buffer.])
+     ;;
+ esac
+])

 
 

-  exit (0);
-}
-         ],
-        jm_cv_func_gettimeofday_clobber=no,
-        jm_cv_func_gettimeofday_clobber=yes,
-        dnl When crosscompiling, assume it is broken.
-        jm_cv_func_gettimeofday_clobber=yes)
-  ])
-  if test $jm_cv_func_gettimeofday_clobber = yes; then
-    AC_LIBOBJ(gettimeofday)
-    AC_DEFINE(localtime, rpl_localtime,
-      [Define to rpl_localtime if the replacement function should be used.])
-    AC_DEFINE(gettimeofday, rpl_gettimeofday,
-      [Define to rpl_gettimeofday if the replacement function should be used.])
-    AC_DEFINE(GETTIMEOFDAY_CLOBBERS_LOCALTIME_BUFFER, 1,
-      [Define if gettimeofday clobbers localtime's static buffer.])
-    gl_PREREQ_GETTIMEOFDAY
-  fi
+AC_DEFUN([gl_GETTIMEOFDAY_REPLACE_LOCALTIME], [
+  REPLACE_GMTIME=1
+  REPLACE_LOCALTIME=1

 ])
 
 # Prerequisites of lib/gettimeofday.c.
 AC_DEFUN([gl_PREREQ_GETTIMEOFDAY], [
 ])
 
 # Prerequisites of lib/gettimeofday.c.
 AC_DEFUN([gl_PREREQ_GETTIMEOFDAY], [

-  AC_REQUIRE([AC_HEADER_TIME])
+  AC_CHECK_HEADERS([sys/timeb.h])
+  AC_CHECK_FUNCS([_ftime])

 ])
 ])