# serial 39 dnl From Jim Meyering. dnl Check for the nanosleep function. dnl If not found, use the supplied replacement. dnl # Copyright (C) 1999-2001, 2003-2020 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], [ AC_REQUIRE([gl_HEADER_TIME_H_DEFAULTS]) AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles dnl Persuade glibc and Solaris <time.h> to declare nanosleep. AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS]) AC_CHECK_HEADERS_ONCE([sys/time.h]) AC_REQUIRE([gl_FUNC_SELECT]) AC_CHECK_DECLS_ONCE([alarm]) nanosleep_save_libs=$LIBS # Solaris 2.5.1 needs -lposix4 to get the nanosleep function. # Solaris 7 prefers the library name -lrt to the obsolescent name -lposix4. LIB_NANOSLEEP= AC_SUBST([LIB_NANOSLEEP]) AC_SEARCH_LIBS([nanosleep], [rt posix4], [test "$ac_cv_search_nanosleep" = "none required" || LIB_NANOSLEEP=$ac_cv_search_nanosleep]) if test "x$ac_cv_search_nanosleep" != xno; then dnl The system has a nanosleep function. AC_REQUIRE([gl_MULTIARCH]) if test $APPLE_UNIVERSAL_BUILD = 1; then # A universal build on Apple Mac OS X platforms. # The test result would be 'no (mishandles large arguments)' in 64-bit # mode but 'yes' in 32-bit mode. But we need a configuration result that # is valid in both modes. gl_cv_func_nanosleep='no (mishandles large arguments)' fi AC_CACHE_CHECK([for working nanosleep], [gl_cv_func_nanosleep], [ 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) 1 << (sizeof (t) * CHAR_BIT - 2)) - 1) * 2 + 1))) #if HAVE_DECL_ALARM static void check_for_SIGALRM (int sig) { if (sig != SIGALRM) _exit (1); } #endif int main () { static struct timespec ts_sleep; static struct timespec ts_remaining; /* Test for major problems first. */ if (! nanosleep) return 2; ts_sleep.tv_sec = 0; ts_sleep.tv_nsec = 1; #if HAVE_DECL_ALARM { static struct sigaction act; act.sa_handler = check_for_SIGALRM; sigemptyset (&act.sa_mask); sigaction (SIGALRM, &act, NULL); alarm (1); if (nanosleep (&ts_sleep, NULL) != 0) return 3; /* Test for a minor problem: the handling of large arguments. */ ts_sleep.tv_sec = TYPE_MAXIMUM (time_t); ts_sleep.tv_nsec = 999999999; alarm (1); if (nanosleep (&ts_sleep, &ts_remaining) != -1) return 4; if (errno != EINTR) return 5; if (ts_remaining.tv_sec <= TYPE_MAXIMUM (time_t) - 10) return 6; } #else /* A simpler test for native Windows. */ if (nanosleep (&ts_sleep, &ts_remaining) < 0) return 3; #endif return 0; }]])], [gl_cv_func_nanosleep=yes], [case $? in dnl ( 4|5|6) gl_cv_func_nanosleep='no (mishandles large arguments)';; dnl ( *) gl_cv_func_nanosleep=no;; esac], [case "$host_os" in dnl (( linux*) # Guess it halfway works when the kernel is Linux. gl_cv_func_nanosleep='guessing no (mishandles large arguments)' ;; mingw*) # Guess no on native Windows. gl_cv_func_nanosleep='guessing no' ;; *) # If we don't know, obey --enable-cross-guesses. gl_cv_func_nanosleep="$gl_cross_guess_normal" ;; esac ]) ]) case "$gl_cv_func_nanosleep" in *yes) REPLACE_NANOSLEEP=0 ;; *) REPLACE_NANOSLEEP=1 case "$gl_cv_func_nanosleep" in *"mishandles large arguments"*) AC_DEFINE([HAVE_BUG_BIG_NANOSLEEP], [1], [Define to 1 if nanosleep mishandles large arguments.]) ;; *) # The replacement uses select(). Add $LIBSOCKET to $LIB_NANOSLEEP. for ac_lib in $LIBSOCKET; do case " $LIB_NANOSLEEP " in *" $ac_lib "*) ;; *) LIB_NANOSLEEP="$LIB_NANOSLEEP $ac_lib";; esac done ;; esac ;; esac else HAVE_NANOSLEEP=0 fi LIBS=$nanosleep_save_libs ]) # Prerequisites of lib/nanosleep.c. AC_DEFUN([gl_PREREQ_NANOSLEEP], [ AC_CHECK_HEADERS_ONCE([sys/select.h]) gl_PREREQ_SIG_HANDLER_H ])