Make it possible to compile setenv.c separately, unconditionally.

[gnulib.git] / m4 / nanosleep.m4

diff --git a/m4/nanosleep.m4 b/m4/nanosleep.m4
index 2d6c90b..a3a6814 100644 (file)
--- a/m4/nanosleep.m4
+++ b/m4/nanosleep.m4
@@ -1,18 +1,25 @@
-#serial 14
+#serial 22

 
 dnl From Jim Meyering.
 dnl Check for the nanosleep function.
 dnl If not found, use the supplied replacement.
 dnl
 
 
 dnl From Jim Meyering.
 dnl Check for the nanosleep function.
 dnl If not found, use the supplied replacement.
 dnl
 

-# Copyright (C) 1999, 2000, 2001, 2003, 2004, 2005 Free Software Foundation, Inc.
+# Copyright (C) 1999, 2000, 2001, 2003, 2004, 2005, 2006, 2007 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.
 
 AC_DEFUN([gl_FUNC_NANOSLEEP],
 [
 # 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.
 
 AC_DEFUN([gl_FUNC_NANOSLEEP],
 [

- AC_LIBSOURCES([nanosleep.c])
+ dnl Persuade glibc and Solaris <time.h> to declare nanosleep.
+ AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
+
+ AC_REQUIRE([gl_HEADER_TIME_H_DEFAULTS])
+ AC_REQUIRE([gl_CLOCK_TIME])
+ AC_CHECK_HEADERS_ONCE(sys/time.h)

 
  nanosleep_save_libs=$LIBS
 
 
  nanosleep_save_libs=$LIBS
 


@@ -21,46 +28,83 @@ AC_DEFUN([gl_FUNC_NANOSLEEP],
  AC_SEARCH_LIBS([nanosleep], [rt posix4],
                 [test "$ac_cv_search_nanosleep" = "none required" ||
                 LIB_NANOSLEEP=$ac_cv_search_nanosleep])
  AC_SEARCH_LIBS([nanosleep], [rt posix4],
                 [test "$ac_cv_search_nanosleep" = "none required" ||
                 LIB_NANOSLEEP=$ac_cv_search_nanosleep])

- AC_SUBST([LIB_NANOSLEEP])

 
 

- AC_CACHE_CHECK([whether nanosleep works],
-  jm_cv_func_nanosleep_works,
+ AC_CACHE_CHECK([for working nanosleep],
+  [gl_cv_func_nanosleep],

   [
   [

-   AC_REQUIRE([AC_HEADER_TIME])
-   AC_CHECK_HEADERS_ONCE(sys/time.h)
-   AC_TRY_RUN([
-#   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_RUN_IFELSE(
+     [AC_LANG_SOURCE([[
+       #include <errno.h>
+       #include <limits.h>
+       #include <signal.h>
+       #if HAVE_SYS_TIME_H
+        #include <sys/time.h>
+       #endif
+       #include <time.h>
+       #include <unistd.h>
+       #define TYPE_SIGNED(t) (! ((t) 0 < (t) -1))
+       #define TYPE_MAXIMUM(t) \
+         ((t) (! TYPE_SIGNED (t) \
+               ? (t) -1 \
+               : ~ (~ (t) 0 << (sizeof (t) * CHAR_BIT - 1))))

 
 

-    int
-    main ()
-    {
-      struct timespec ts_sleep, ts_remaining;
-      ts_sleep.tv_sec = 0;
-      ts_sleep.tv_nsec = 1;
-      exit (nanosleep (&ts_sleep, &ts_remaining) == 0 ? 0 : 1);
-    }
-         ],
-        jm_cv_func_nanosleep_works=yes,
-        jm_cv_func_nanosleep_works=no,
-        dnl When crosscompiling, assume the worst.
-        jm_cv_func_nanosleep_works=no)
+       static void
+       check_for_SIGALRM (int sig)
+       {
+         if (sig != SIGALRM)
+           _exit (1);
+       }
+
+       int
+       main ()
+       {
+         static struct timespec ts_sleep;
+         static struct timespec ts_remaining;
+         static struct sigaction act;
+         if (! nanosleep)
+           return 1;
+         act.sa_handler = check_for_SIGALRM;
+         sigemptyset (&act.sa_mask);
+         sigaction (SIGALRM, &act, NULL);
+         ts_sleep.tv_sec = 0;
+         ts_sleep.tv_nsec = 1;
+         alarm (1);
+         if (nanosleep (&ts_sleep, NULL) != 0)
+           return 1;
+         ts_sleep.tv_sec = TYPE_MAXIMUM (time_t);
+         ts_sleep.tv_nsec = 999999999;
+         alarm (1);
+         if (nanosleep (&ts_sleep, &ts_remaining) == -1 && errno == EINTR
+             && TYPE_MAXIMUM (time_t) - 10 < ts_remaining.tv_sec)
+           return 0;
+         return 119;
+       }]])],
+     [gl_cv_func_nanosleep=yes],
+     [case $? in dnl (
+      119) gl_cv_func_nanosleep='no (mishandles large arguments)';; dnl (
+      *)   gl_cv_func_nanosleep=no;;
+      esac],
+     [gl_cv_func_nanosleep=cross-compiling])

   ])
   ])

-  if test $jm_cv_func_nanosleep_works = no; then
+  if test "$gl_cv_func_nanosleep" = yes; then
+    REPLACE_NANOSLEEP=0
+  else
+    REPLACE_NANOSLEEP=1
+    if test "$gl_cv_func_nanosleep" = 'no (mishandles large arguments)'; then
+      AC_DEFINE([HAVE_BUG_BIG_NANOSLEEP], 1,
+       [Define to 1 if nanosleep mishandle large arguments.])
+      for ac_lib in $LIB_CLOCK_GETTIME; do
+       case " $LIB_NANOSLEEP " in
+       *" $ac_lib "*) ;;
+       *) LIB_NANOSLEEP="$LIB_NANOSLEEP $ac_lib";;
+       esac
+      done
+    fi

     AC_LIBOBJ(nanosleep)
     AC_LIBOBJ(nanosleep)

-    AC_DEFINE(nanosleep, rpl_nanosleep,
-      [Define to rpl_nanosleep if the replacement function should be used.])

     gl_PREREQ_NANOSLEEP
   fi
 
     gl_PREREQ_NANOSLEEP
   fi
 

+ AC_SUBST([LIB_NANOSLEEP])

  LIBS=$nanosleep_save_libs
 ])
 
  LIBS=$nanosleep_save_libs
 ])
 


@@ -68,4 +112,5 @@ AC_DEFUN([gl_FUNC_NANOSLEEP],
 AC_DEFUN([gl_PREREQ_NANOSLEEP],
 [
   AC_CHECK_FUNCS_ONCE(siginterrupt)
 AC_DEFUN([gl_PREREQ_NANOSLEEP],
 [
   AC_CHECK_FUNCS_ONCE(siginterrupt)

+  AC_CHECK_HEADERS_ONCE(sys/select.h)

 ])
 ])