Files
Paul Eggert 990fa9d50c open: support O_CLOEXEC
* NEWS, doc/posix-functions/open.texi:
* doc/posix-functions/openat.texi: Document this.
* lib/fcntl.in.h (O_CLOEXEC): Default to a nonzero value.
(GNULIB_defined_O_CLOEXEC): New symbol.
* lib/open.c: Include cloexec.h.
(open): Support O_CLOEXEC.
* lib/openat.c: Include cloexec.h.
(rpl_openat): Support O_CLOEXEC.
* lib/popen-safer.c: Do not include cloexec.h.
(open_noinherit): Remove.
(popen_safer): Use O_CLOEXEC instead of set_cloexec_flag.
* lib/save-cwd.c: Do not include cloexec.h.
(save_cwd): Use O_CLOEXEC instead of set_cloexec_flag.
* m4/open-cloexec.m4: New file.
* m4/open.m4 (gl_FUNC_OPEN): Require gl_PREPROC_O_CLOEXEC.
Replace 'open' if O_CLOEXEC is not present.
* m4/openat.m4 (gl_FUNC_OPENAT): Require gl_PREPROC_O_CLOEXEC.
Replace 'openat' if O_CLOEXEC is not present.
* modules/freopen (Depends-on): Depend on 'open' if replacing freopen.
* modules/open (Files): Add m4/open-cloexec.m4.
(Depends-on): Depend on cloexec if replacing 'open'.
* modules/openat (Files): Add m4/open-cloexec.m4.
(Depends-on): Depend on cloexec if replacing openat.
* modules/popen-safer (Depends-on): Remove cloexec.
* modules/save-cwd (Depends-on): Remove cloexec, and add
fd-safer-flag and 'open'.
2017-08-14 13:05:23 -07:00

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# open.m4 serial 15
dnl Copyright (C) 2007-2017 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])
:
])