-# fcntl.m4 serial 5
-dnl Copyright (C) 2009-2013 Free Software Foundation, Inc.
+# fcntl.m4 serial 11
+dnl Copyright (C) 2009-2021 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
dnl with or without modifications, as long as this notice is preserved.
dnl haiku alpha 2 F_DUPFD has wrong errno
AC_CACHE_CHECK([whether fcntl handles F_DUPFD correctly],
[gl_cv_func_fcntl_f_dupfd_works],
- [AC_RUN_IFELSE([AC_LANG_PROGRAM([[
-#include <fcntl.h>
-#include <errno.h>
-]], [[int result = 0;
- if (fcntl (0, F_DUPFD, -1) != -1) result |= 1;
- if (errno != EINVAL) result |= 2;
- return result;
- ]])],
+ [AC_RUN_IFELSE(
+ [AC_LANG_PROGRAM(
+ [[#include <errno.h>
+ #include <fcntl.h>
+ #include <limits.h>
+ #include <sys/resource.h>
+ #include <unistd.h>
+ ]GL_MDA_DEFINES[
+ #ifndef RLIM_SAVED_CUR
+ # define RLIM_SAVED_CUR RLIM_INFINITY
+ #endif
+ #ifndef RLIM_SAVED_MAX
+ # define RLIM_SAVED_MAX RLIM_INFINITY
+ #endif
+ ]],
+ [[int result = 0;
+ int bad_fd = INT_MAX;
+ struct rlimit rlim;
+ if (getrlimit (RLIMIT_NOFILE, &rlim) == 0
+ && 0 <= rlim.rlim_cur && rlim.rlim_cur <= INT_MAX
+ && rlim.rlim_cur != RLIM_INFINITY
+ && rlim.rlim_cur != RLIM_SAVED_MAX
+ && rlim.rlim_cur != RLIM_SAVED_CUR)
+ bad_fd = rlim.rlim_cur;
+ if (fcntl (0, F_DUPFD, -1) != -1) result |= 1;
+ if (errno != EINVAL) result |= 2;
+ if (fcntl (0, F_DUPFD, bad_fd) != -1) result |= 4;
+ if (errno != EINVAL) result |= 8;
+ /* On OS/2 kLIBC, F_DUPFD does not work on a directory fd */
+ {
+ int fd;
+ fd = open (".", O_RDONLY);
+ if (fd == -1)
+ result |= 16;
+ else if (fcntl (fd, F_DUPFD, STDERR_FILENO + 1) == -1)
+ result |= 32;
+
+ close (fd);
+ }
+ return result;]])],
[gl_cv_func_fcntl_f_dupfd_works=yes],
[gl_cv_func_fcntl_f_dupfd_works=no],
- [# Guess that it works on glibc systems
- case $host_os in #((
- *-gnu*) gl_cv_func_fcntl_f_dupfd_works="guessing yes";;
- *) gl_cv_func_fcntl_f_dupfd_works="guessing no";;
+ [case $host_os in
+ aix* | cygwin* | haiku*)
+ gl_cv_func_fcntl_f_dupfd_works="guessing no" ;;
+ *) gl_cv_func_fcntl_f_dupfd_works="guessing yes" ;;
esac])])
case $gl_cv_func_fcntl_f_dupfd_works in
*yes) ;;
behavior does not match POSIX]) ;;
esac
- dnl Many systems lack F_DUPFD_CLOEXEC
+ dnl Many systems lack F_DUPFD_CLOEXEC.
+ dnl NetBSD 9.0 declares F_DUPFD_CLOEXEC but it works only like F_DUPFD.
AC_CACHE_CHECK([whether fcntl understands F_DUPFD_CLOEXEC],
[gl_cv_func_fcntl_f_dupfd_cloexec],
- [AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
-#include <fcntl.h>
-#ifndef F_DUPFD_CLOEXEC
-choke me
-#endif
- ]])],
+ [AC_RUN_IFELSE(
+ [AC_LANG_SOURCE(
+ [[#include <fcntl.h>
+ #include <unistd.h>
+ int main (int argc, char *argv[])
+ {
+ if (argc == 1)
+ /* parent process */
+ {
+ if (fcntl (1, F_DUPFD_CLOEXEC, 10) < 0)
+ return 1;
+ return execl ("./conftest", "./conftest", "child", NULL);
+ }
+ else
+ /* child process */
+ return (fcntl (10, F_GETFL) < 0 ? 0 : 42);
+ }
+ ]])
+ ],
[AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
#ifdef __linux__
/* The Linux kernel only added F_DUPFD_CLOEXEC in 2.6.24, so we always replace
#endif
]])],
[gl_cv_func_fcntl_f_dupfd_cloexec=yes],
- [gl_cv_func_fcntl_f_dupfd_cloexec="needs runtime check"])],
- [gl_cv_func_fcntl_f_dupfd_cloexec=no])])
- if test "$gl_cv_func_fcntl_f_dupfd_cloexec" != yes; then
- gl_REPLACE_FCNTL
- dnl No witness macro needed for this bug.
- fi
+ [gl_cv_func_fcntl_f_dupfd_cloexec="needs runtime check"])
+ ],
+ [gl_cv_func_fcntl_f_dupfd_cloexec=no],
+ [case "$host_os" in
+ # Guess no on NetBSD.
+ netbsd*) gl_cv_func_fcntl_f_dupfd_cloexec="guessing no" ;;
+ *) gl_cv_func_fcntl_f_dupfd_cloexec="$gl_cross_guess_normal" ;;
+ esac
+ ])
+ ])
+ case "$gl_cv_func_fcntl_f_dupfd_cloexec" in
+ *yes) ;;
+ *) gl_REPLACE_FCNTL
+ dnl No witness macro needed for this bug.
+ ;;
+ esac
fi
dnl Replace fcntl() for supporting the gnulib-defined fchdir() function,
dnl to keep fchdir's bookkeeping up-to-date.