1
0
mirror of https://git.savannah.gnu.org/git/emacs.git synced 2024-12-28 10:56:36 +00:00
emacs/m4/open.m4
Paul Eggert 220a9ecba1 Merge from Gnulib
This incorporates:
2018-01-01 maint: Run 'make update-copyright'
2017-12-29 Add cross-compilation results for GNU/Hurd.
2017-12-12 explicit_bzero: port to macOS + Clang 9.0.0
2017-12-31 17:21:33 -08:00

96 lines
2.7 KiB
Plaintext

# open.m4 serial 15
dnl Copyright (C) 2007-2018 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.
AC_DEFUN([gl_FUNC_OPEN],
[
AC_REQUIRE([AC_CANONICAL_HOST])
AC_REQUIRE([gl_PREPROC_O_CLOEXEC])
case "$host_os" in
mingw* | pw*)
REPLACE_OPEN=1
;;
*)
dnl open("foo/") should not create a file when the file name has a
dnl trailing slash. FreeBSD only has the problem on symlinks.
AC_CHECK_FUNCS_ONCE([lstat])
if test "$gl_cv_macro_O_CLOEXEC" != yes; then
REPLACE_OPEN=1
fi
AC_CACHE_CHECK([whether open recognizes a trailing slash],
[gl_cv_func_open_slash],
[# Assume that if we have lstat, we can also check symlinks.
if test $ac_cv_func_lstat = yes; then
touch conftest.tmp
ln -s conftest.tmp conftest.lnk
fi
AC_RUN_IFELSE(
[AC_LANG_SOURCE([[
#include <fcntl.h>
#if HAVE_UNISTD_H
# include <unistd.h>
#endif
int main ()
{
int result = 0;
#if HAVE_LSTAT
if (open ("conftest.lnk/", O_RDONLY) != -1)
result |= 1;
#endif
if (open ("conftest.sl/", O_CREAT, 0600) >= 0)
result |= 2;
return result;
}]])],
[gl_cv_func_open_slash=yes],
[gl_cv_func_open_slash=no],
[
changequote(,)dnl
case "$host_os" in
freebsd* | aix* | hpux* | solaris2.[0-9] | solaris2.[0-9].*)
gl_cv_func_open_slash="guessing no" ;;
*)
gl_cv_func_open_slash="guessing yes" ;;
esac
changequote([,])dnl
])
rm -f conftest.sl conftest.tmp conftest.lnk
])
case "$gl_cv_func_open_slash" in
*no)
AC_DEFINE([OPEN_TRAILING_SLASH_BUG], [1],
[Define to 1 if open() fails to recognize a trailing slash.])
REPLACE_OPEN=1
;;
esac
;;
esac
dnl Replace open() for supporting the gnulib-defined fchdir() function,
dnl to keep fchdir's bookkeeping up-to-date.
m4_ifdef([gl_FUNC_FCHDIR], [
if test $REPLACE_OPEN = 0; then
gl_TEST_FCHDIR
if test $HAVE_FCHDIR = 0; then
REPLACE_OPEN=1
fi
fi
])
dnl Replace open() for supporting the gnulib-defined O_NONBLOCK flag.
m4_ifdef([gl_NONBLOCKING_IO], [
if test $REPLACE_OPEN = 0; then
gl_NONBLOCKING_IO
if test $gl_cv_have_open_O_NONBLOCK != yes; then
REPLACE_OPEN=1
fi
fi
])
])
# Prerequisites of lib/open.c.
AC_DEFUN([gl_PREREQ_OPEN],
[
AC_REQUIRE([gl_PROMOTED_TYPE_MODE_T])
:
])