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Diffstat (limited to 'gl/m4/nanosleep.m4')
| -rw-r--r-- | gl/m4/nanosleep.m4 | 161 |
1 files changed, 161 insertions, 0 deletions
diff --git a/gl/m4/nanosleep.m4 b/gl/m4/nanosleep.m4 new file mode 100644 index 0000000..1fb13ed --- /dev/null +++ b/gl/m4/nanosleep.m4 @@ -0,0 +1,161 @@ +# 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 +]) |