Commit 62fb0759 authored by Ondřej Surý's avatar Ondřej Surý
Browse files

Assume always working getaddrinfo/getnameinfo implemenation

parent 29c853f5
......@@ -50,15 +50,6 @@
/** define if tzset() is available */
#undef HAVE_TZSET
/** define if struct addrinfo exists */
#undef HAVE_ADDRINFO
/** define if getaddrinfo() exists */
#undef HAVE_GETADDRINFO
/** define if gai_strerror() exists */
#undef HAVE_GAISTRERROR
/**
* define if pthread_setconcurrency() should be called to tell the
* OS how many threads we might want to run.
......
......@@ -62,14 +62,6 @@
#define CHECK_LOCAL 1
#endif
#ifdef HAVE_ADDRINFO
#ifdef HAVE_GETADDRINFO
#ifdef HAVE_GAISTRERROR
#define USE_GETADDRINFO
#endif
#endif
#endif
#define CHECK(r) \
do { \
result = (r); \
......@@ -177,7 +169,6 @@ static bool
checkns(dns_zone_t *zone, const dns_name_t *name, const dns_name_t *owner,
dns_rdataset_t *a, dns_rdataset_t *aaaa)
{
#ifdef USE_GETADDRINFO
dns_rdataset_t *rdataset;
dns_rdata_t rdata = DNS_RDATA_INIT;
struct addrinfo hints, *ai, *cur;
......@@ -373,14 +364,10 @@ checkns(dns_zone_t *zone, const dns_name_t *name, const dns_name_t *owner,
}
freeaddrinfo(ai);
return (answer);
#else
return (true);
#endif
}
static bool
checkmx(dns_zone_t *zone, const dns_name_t *name, const dns_name_t *owner) {
#ifdef USE_GETADDRINFO
struct addrinfo hints, *ai, *cur;
char namebuf[DNS_NAME_FORMATSIZE + 1];
char ownerbuf[DNS_NAME_FORMATSIZE];
......@@ -459,14 +446,10 @@ checkmx(dns_zone_t *zone, const dns_name_t *name, const dns_name_t *owner) {
}
return (true);
}
#else
return (true);
#endif
}
static bool
checksrv(dns_zone_t *zone, const dns_name_t *name, const dns_name_t *owner) {
#ifdef USE_GETADDRINFO
struct addrinfo hints, *ai, *cur;
char namebuf[DNS_NAME_FORMATSIZE + 1];
char ownerbuf[DNS_NAME_FORMATSIZE];
......@@ -544,9 +527,6 @@ checksrv(dns_zone_t *zone, const dns_name_t *name, const dns_name_t *owner) {
}
return (true);
}
#else
return (true);
#endif
}
isc_result_t
......@@ -791,4 +771,3 @@ DestroySockets(void) {
WSACleanup();
}
#endif
......@@ -99,20 +99,6 @@
#endif
#endif
#ifdef HAVE_ADDRINFO
#ifdef HAVE_GETADDRINFO
#ifdef HAVE_GAISTRERROR
#define USE_GETADDRINFO
#endif
#endif
#endif
#ifndef USE_GETADDRINFO
#ifndef ISC_PLATFORM_NONSTDHERRNO
extern int h_errno;
#endif
#endif
#define MAXCMD (128 * 1024)
#define MAXWIRE (64 * 1024)
#define PACKETSIZE ((64 * 1024) - 1)
......
......@@ -50,15 +50,6 @@
/** define if tzset() is available */
#undef HAVE_TZSET
/** define if struct addrinfo exists */
#undef HAVE_ADDRINFO
/** define if getaddrinfo() exists */
#undef HAVE_GETADDRINFO
/** define if gai_strerror() exists */
#undef HAVE_GAISTRERROR
/**
* define if pthread_setconcurrency() should be called to tell the
* OS how many threads we might want to run.
......@@ -486,18 +477,6 @@
/* Use HMAC-SHA256 for Client Cookie generation */
#undef HMAC_SHA256_CC
/* return type of gai_strerror */
#undef IRS_GAISTRERROR_RETURN_T
/* Define to the buffer length type used by getnameinfo(3). */
#undef IRS_GETNAMEINFO_BUFLEN_T
/* Define to the flags type used by getnameinfo(3). */
#undef IRS_GETNAMEINFO_FLAGS_T
/* Define to the sockaddr length type used by getnameinfo(3). */
#undef IRS_GETNAMEINFO_SOCKLEN_T
/* Define if you want to use inline buffers */
#undef ISC_BUFFER_USEINLINE
......
......@@ -289,27 +289,6 @@ typedef __int64 off_t;
*/
@HAVE_LIBXML2@
/** define if struct addrinfo exists */
#define HAVE_ADDRINFO
/** define if getaddrinfo() exists */
#define HAVE_GETADDRINFO
/** define if gai_strerror() exists */
#define HAVE_GAISTRERROR
/* return type of gai_strerror */
#define IRS_GAISTRERROR_RETURN_T char *
/* Define to the buffer length type used by getnameinfo(3). */
#define IRS_GETNAMEINFO_BUFLEN_T DWORD
/* Define to the flags type used by getnameinfo(3). */
#define IRS_GETNAMEINFO_FLAGS_T int
/* Define to the sockaddr length type used by getnameinfo(3). */
#define IRS_GETNAMEINFO_SOCKLEN_T socklen_t
/* Define to enable "rrset-order fixed" syntax. */
@DNS_RDATASET_FIXED@
......
......@@ -735,8 +735,6 @@ ISC_PLATFORM_NEEDSTRLCPY
GENRANDOMLIB
ISC_PLATFORM_NEEDSTRTOUL
ISC_PLATFORM_NEEDMEMMOVE
ISC_IRS_GETNAMEINFOSOCKLEN
ISC_IRS_NEEDADDRINFO
ISC_PLATFORM_HAVETFO
ISC_PLATFORM_HAVEIF_LADDRCONF
ISC_PLATFORM_HAVEIF_LADDRREQ
......@@ -17964,187 +17962,6 @@ $as_echo "disabled" >&6; }
esac
 
 
#
# Check for addrinfo
#
{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for struct addrinfo" >&5
$as_echo_n "checking for struct addrinfo... " >&6; }
cat confdefs.h - <<_ACEOF >conftest.$ac_ext
/* end confdefs.h. */
#include <netdb.h>
int
main ()
{
struct addrinfo a; return (0);
;
return 0;
}
_ACEOF
if ac_fn_c_try_compile "$LINENO"; then :
{ $as_echo "$as_me:${as_lineno-$LINENO}: result: yes" >&5
$as_echo "yes" >&6; }
ISC_IRS_NEEDADDRINFO="#undef ISC_IRS_NEEDADDRINFO"
$as_echo "#define HAVE_ADDRINFO 1" >>confdefs.h
else
{ $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
$as_echo "no" >&6; }
ISC_IRS_NEEDADDRINFO="#define ISC_IRS_NEEDADDRINFO 1"
fi
rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
#
# Sadly, the definitions of system-supplied getnameinfo(3) vary. Try to catch
# known variations here:
#
{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for getnameinfo prototype definitions" >&5
$as_echo_n "checking for getnameinfo prototype definitions... " >&6; }
cat confdefs.h - <<_ACEOF >conftest.$ac_ext
/* end confdefs.h. */
#include <sys/types.h>
#include <sys/socket.h>
#include <netdb.h>
int getnameinfo(const struct sockaddr *, socklen_t, char *,
socklen_t, char *, socklen_t, unsigned int);
int
main ()
{
return (0);
;
return 0;
}
_ACEOF
if ac_fn_c_try_compile "$LINENO"; then :
{ $as_echo "$as_me:${as_lineno-$LINENO}: result: socklen_t for buflen; u_int for flags" >&5
$as_echo "socklen_t for buflen; u_int for flags" >&6; }
$as_echo "#define IRS_GETNAMEINFO_SOCKLEN_T socklen_t" >>confdefs.h
$as_echo "#define IRS_GETNAMEINFO_BUFLEN_T socklen_t" >>confdefs.h
$as_echo "#define IRS_GETNAMEINFO_FLAGS_T unsigned int" >>confdefs.h
else
cat confdefs.h - <<_ACEOF >conftest.$ac_ext
/* end confdefs.h. */
#include <sys/types.h>
#include <sys/socket.h>
#include <netdb.h>
int getnameinfo(const struct sockaddr *, socklen_t, char *,
size_t, char *, size_t, int);
int
main ()
{
return (0);
;
return 0;
}
_ACEOF
if ac_fn_c_try_compile "$LINENO"; then :
{ $as_echo "$as_me:${as_lineno-$LINENO}: result: size_t for buflen; int for flags" >&5
$as_echo "size_t for buflen; int for flags" >&6; }
$as_echo "#define IRS_GETNAMEINFO_SOCKLEN_T socklen_t" >>confdefs.h
$as_echo "#define IRS_GETNAMEINFO_BUFLEN_T size_t" >>confdefs.h
$as_echo "#define IRS_GETNAMEINFO_FLAGS_T int" >>confdefs.h
else
cat confdefs.h - <<_ACEOF >conftest.$ac_ext
/* end confdefs.h. */
#include <sys/types.h>
#include <sys/socket.h>
#include <netdb.h>
int getnameinfo(const struct sockaddr *, size_t, char *,
size_t, char *, size_t, int);
int
main ()
{
return (0);
;
return 0;
}
_ACEOF
if ac_fn_c_try_compile "$LINENO"; then :
{ $as_echo "$as_me:${as_lineno-$LINENO}: result: size_t for buflen; int for flags" >&5
$as_echo "size_t for buflen; int for flags" >&6; }
$as_echo "#define IRS_GETNAMEINFO_SOCKLEN_T size_t" >>confdefs.h
$as_echo "#define IRS_GETNAMEINFO_BUFLEN_T size_t" >>confdefs.h
$as_echo "#define IRS_GETNAMEINFO_FLAGS_T int" >>confdefs.h
else
{ $as_echo "$as_me:${as_lineno-$LINENO}: result: not match any subspecies; assume standard definition" >&5
$as_echo "not match any subspecies; assume standard definition" >&6; }
$as_echo "#define IRS_GETNAMEINFO_SOCKLEN_T socklen_t" >>confdefs.h
$as_echo "#define IRS_GETNAMEINFO_BUFLEN_T socklen_t" >>confdefs.h
$as_echo "#define IRS_GETNAMEINFO_FLAGS_T int" >>confdefs.h
fi
rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
fi
rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
fi
rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
#
# ...and same for gai_strerror().
#
{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for gai_strerror prototype definitions" >&5
$as_echo_n "checking for gai_strerror prototype definitions... " >&6; }
cat confdefs.h - <<_ACEOF >conftest.$ac_ext
/* end confdefs.h. */
#include <sys/types.h>
#include <sys/socket.h>
#include <netdb.h>
char *gai_strerror(int ecode);
int
main ()
{
return (0);
;
return 0;
}
_ACEOF
if ac_fn_c_try_compile "$LINENO"; then :
{ $as_echo "$as_me:${as_lineno-$LINENO}: result: returning char *" >&5
$as_echo "returning char *" >&6; }
$as_echo "#define IRS_GAISTRERROR_RETURN_T char *" >>confdefs.h
else
{ $as_echo "$as_me:${as_lineno-$LINENO}: result: not match any subspecies; assume standard definition" >&5
$as_echo "not match any subspecies; assume standard definition" >&6; }
$as_echo "#define IRS_GAISTRERROR_RETURN_T const char *" >>confdefs.h
fi
rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
ac_fn_c_check_func "$LINENO" "getaddrinfo" "ac_cv_func_getaddrinfo"
if test "x$ac_cv_func_getaddrinfo" = xyes; then :
$as_echo "#define HAVE_GETADDRINFO 1" >>confdefs.h
fi
ac_fn_c_check_func "$LINENO" "gai_strerror" "ac_cv_func_gai_strerror"
if test "x$ac_cv_func_gai_strerror" = xyes; then :
$as_echo "#define HAVE_GAISTRERROR 1" >>confdefs.h
fi
# Check whether --enable-getifaddrs was given.
if test "${enable_getifaddrs+set}" = set; then :
enableval=$enable_getifaddrs; want_getifaddrs="$enableval"
......
......@@ -2011,86 +2011,6 @@ int has_tfo() { return (0); }
esac
AC_SUBST(ISC_PLATFORM_HAVETFO)
#
# Check for addrinfo
#
AC_MSG_CHECKING(for struct addrinfo)
AC_TRY_COMPILE([
#include <netdb.h>],
[struct addrinfo a; return (0);],
[AC_MSG_RESULT(yes)
ISC_IRS_NEEDADDRINFO="#undef ISC_IRS_NEEDADDRINFO"
AC_DEFINE(HAVE_ADDRINFO)],
[AC_MSG_RESULT(no)
ISC_IRS_NEEDADDRINFO="#define ISC_IRS_NEEDADDRINFO 1"])
AC_SUBST(ISC_IRS_NEEDADDRINFO)
#
# Sadly, the definitions of system-supplied getnameinfo(3) vary. Try to catch
# known variations here:
#
AC_MSG_CHECKING(for getnameinfo prototype definitions)
AC_TRY_COMPILE([
#include <sys/types.h>
#include <sys/socket.h>
#include <netdb.h>
int getnameinfo(const struct sockaddr *, socklen_t, char *,
socklen_t, char *, socklen_t, unsigned int);],
[ return (0);],
[AC_MSG_RESULT(socklen_t for buflen; u_int for flags)
AC_DEFINE(IRS_GETNAMEINFO_SOCKLEN_T, socklen_t,
[Define to the sockaddr length type used by getnameinfo(3).])
AC_DEFINE(IRS_GETNAMEINFO_BUFLEN_T, socklen_t,
[Define to the buffer length type used by getnameinfo(3).])
AC_DEFINE(IRS_GETNAMEINFO_FLAGS_T, unsigned int,
[Define to the flags type used by getnameinfo(3).])],
[AC_TRY_COMPILE([
#include <sys/types.h>
#include <sys/socket.h>
#include <netdb.h>
int getnameinfo(const struct sockaddr *, socklen_t, char *,
size_t, char *, size_t, int);],
[ return (0);],
[AC_MSG_RESULT(size_t for buflen; int for flags)
AC_DEFINE(IRS_GETNAMEINFO_SOCKLEN_T, socklen_t)
AC_DEFINE(IRS_GETNAMEINFO_BUFLEN_T, size_t)
AC_DEFINE(IRS_GETNAMEINFO_FLAGS_T, int)],
[AC_TRY_COMPILE([
#include <sys/types.h>
#include <sys/socket.h>
#include <netdb.h>
int getnameinfo(const struct sockaddr *, size_t, char *,
size_t, char *, size_t, int);],
[ return (0);],
[AC_MSG_RESULT(size_t for buflen; int for flags)
AC_DEFINE(IRS_GETNAMEINFO_SOCKLEN_T, size_t)
AC_DEFINE(IRS_GETNAMEINFO_BUFLEN_T, size_t)
AC_DEFINE(IRS_GETNAMEINFO_FLAGS_T, int)],
[AC_MSG_RESULT(not match any subspecies; assume standard definition)
AC_DEFINE(IRS_GETNAMEINFO_SOCKLEN_T, socklen_t)
AC_DEFINE(IRS_GETNAMEINFO_BUFLEN_T, socklen_t)
AC_DEFINE(IRS_GETNAMEINFO_FLAGS_T, int)])])])
#
# ...and same for gai_strerror().
#
AC_MSG_CHECKING(for gai_strerror prototype definitions)
AC_TRY_COMPILE([
#include <sys/types.h>
#include <sys/socket.h>
#include <netdb.h>
char *gai_strerror(int ecode);],
[ return (0); ],
[AC_MSG_RESULT(returning char *)
AC_DEFINE([IRS_GAISTRERROR_RETURN_T], [char *],
[return type of gai_strerror])],
[AC_MSG_RESULT(not match any subspecies; assume standard definition)
AC_DEFINE([IRS_GAISTRERROR_RETURN_T], [const char *])])
AC_CHECK_FUNC(getaddrinfo, AC_DEFINE(HAVE_GETADDRINFO))
AC_CHECK_FUNC(gai_strerror, AC_DEFINE(HAVE_GAISTRERROR))
AC_SUBST(ISC_IRS_GETNAMEINFOSOCKLEN)
AC_ARG_ENABLE(getifaddrs,
AS_HELP_STRING([--enable-getifaddrs],
[enable the use of getifaddrs() [yes|no].]),
......
/* config.h.in. Generated from configure.in by autoheader. */
/* Define to 1 if you have the `getaddrinfo' function. */
#undef HAVE_GETADDRINFO
/* Define to 1 if you have the `gethostbyname2' function. */
#undef HAVE_GETHOSTBYNAME2
/* Define to 1 if you have the `getnameinfo' function. */
#undef HAVE_GETNAMEINFO
/* Define to 1 if you have the `nsl' library (-lnsl). */
#undef HAVE_LIBNSL
......@@ -30,6 +24,9 @@
/* Define to the one symbol short name of this package. */
#undef PACKAGE_TARNAME
/* Define to the home page for this package. */
#undef PACKAGE_URL
/* Define to the version of this package. */
#undef PACKAGE_VERSION
......
#! /bin/sh
# Guess values for system-dependent variables and create Makefiles.
# Generated by GNU Autoconf 2.68.
# Generated by GNU Autoconf 2.69.
#
#
# Copyright (C) 1992, 1993, 1994, 1995, 1996, 1998, 1999, 2000, 2001,
# 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010 Free Software
# Foundation, Inc.
# Copyright (C) 1992-1996, 1998-2012 Free Software Foundation, Inc.
#
#
# This configure script is free software; the Free Software Foundation
......@@ -134,6 +132,31 @@ export LANGUAGE
# CDPATH.
(unset CDPATH) >/dev/null 2>&1 && unset CDPATH
# Use a proper internal environment variable to ensure we don't fall
# into an infinite loop, continuously re-executing ourselves.
if test x"${_as_can_reexec}" != xno && test "x$CONFIG_SHELL" != x; then
_as_can_reexec=no; export _as_can_reexec;
# We cannot yet assume a decent shell, so we have to provide a
# neutralization value for shells without unset; and this also
# works around shells that cannot unset nonexistent variables.
# Preserve -v and -x to the replacement shell.
BASH_ENV=/dev/null
ENV=/dev/null
(unset BASH_ENV) >/dev/null 2>&1 && unset BASH_ENV ENV
case $- in # ((((
*v*x* | *x*v* ) as_opts=-vx ;;
*v* ) as_opts=-v ;;
*x* ) as_opts=-x ;;
* ) as_opts= ;;
esac
exec $CONFIG_SHELL $as_opts "$as_myself" ${1+"$@"}
# Admittedly, this is quite paranoid, since all the known shells bail
# out after a failed `exec'.
$as_echo "$0: could not re-execute with $CONFIG_SHELL" >&2
as_fn_exit 255
fi
# We don't want this to propagate to other subprocesses.
{ _as_can_reexec=; unset _as_can_reexec;}
if test "x$CONFIG_SHELL" = x; then
as_bourne_compatible="if test -n \"\${ZSH_VERSION+set}\" && (emulate sh) >/dev/null 2>&1; then :
emulate sh
......@@ -167,7 +190,8 @@ if ( set x; as_fn_ret_success y && test x = \"\$1\" ); then :
else
exitcode=1; echo positional parameters were not saved.
fi
test x\$exitcode = x0 || exit 1"
test x\$exitcode = x0 || exit 1
test -x / || exit 1"
as_suggested=" as_lineno_1=";as_suggested=$as_suggested$LINENO;as_suggested=$as_suggested" as_lineno_1a=\$LINENO
as_lineno_2=";as_suggested=$as_suggested$LINENO;as_suggested=$as_suggested" as_lineno_2a=\$LINENO
eval 'test \"x\$as_lineno_1'\$as_run'\" != \"x\$as_lineno_2'\$as_run'\" &&
......@@ -211,21 +235,25 @@ IFS=$as_save_IFS
if test "x$CONFIG_SHELL" != x; then :
# We cannot yet assume a decent shell, so we have to provide a
# neutralization value for shells without unset; and this also
# works around shells that cannot unset nonexistent variables.
# Preserve -v and -x to the replacement shell.
BASH_ENV=/dev/null
ENV=/dev/null
(unset BASH_ENV) >/dev/null 2>&1 && unset BASH_ENV ENV
export CONFIG_SHELL
case $- in # ((((
*v*x* | *x*v* ) as_opts=-vx ;;
*v* ) as_opts=-v ;;
*x* ) as_opts=-x ;;
* ) as_opts= ;;
esac
exec "$CONFIG_SHELL" $as_opts "$as_myself" ${1+"$@"}
export CONFIG_SHELL
# We cannot yet assume a decent shell, so we have to provide a
# neutralization value for shells without unset; and this also
# works around shells that cannot unset nonexistent variables.
# Preserve -v and -x to the replacement shell.
BASH_ENV=/dev/null
ENV=/dev/null
(unset BASH_ENV) >/dev/null 2>&1 && unset BASH_ENV ENV
case $- in # ((((
*v*x* | *x*v* ) as_opts=-vx ;;
*v* ) as_opts=-v ;;
*x* ) as_opts=-x ;;
* ) as_opts= ;;
esac
exec $CONFIG_SHELL $as_opts "$as_myself" ${1+"$@"}
# Admittedly, this is quite paranoid, since all the known shells bail
# out after a failed `exec'.
$as_echo "$0: could not re-execute with $CONFIG_SHELL" >&2
exit 255
fi
if test x$as_have_required = xno; then :
......@@ -327,6 +355,14 @@ $as_echo X"$as_dir" |
} # as_fn_mkdir_p
# as_fn_executable_p FILE
# -----------------------
# Test if FILE is an executable regular file.
as_fn_executable_p ()
{
test -f "$1" && test -x "$1"
} # as_fn_executable_p
# as_fn_append VAR VALUE
# ----------------------
# Append the text in VALUE to the end of the definition contained in VAR. Take
......@@ -448,6 +484,10 @@ as_cr_alnum=$as_cr_Letters$as_cr_digits
chmod +x "$as_me.lineno" ||
{ $as_echo "$as_me: error: cannot create $as_me.lineno; rerun with a POSIX shell" >&2; as_fn_exit 1; }
# If we had to re-execute with $CONFIG_SHELL, we're ensured to have
# already done that, so ensure we don't try to do so again and fall
# in an infinite loop. This has already happened in practice.
_as_can_reexec=no; export _as_can_reexec
# Don't try to exec as it changes $[0], causing all sort of problems
# (the dirname of $[0] is not the place where we might find the
# original and so on. Autoconf is especially sensitive to this).
......@@ -482,16 +522,16 @@ if (echo >conf$$.file) 2>/dev/null; then
# ... but there are two gotchas:
# 1) On MSYS, both `ln -s file dir' and `ln file dir' fail.
# 2) DJGPP < 2.04 has no symlinks; `ln -s' creates a wrapper executable.
# In both cases, we have to default to `cp -p'.
# In both cases, we have to default to `cp -pR'.
ln -s conf$$.file conf$$.dir 2>/dev/null && test ! -f conf$$.exe ||
as_ln_s='cp -p'
as_ln_s='cp -pR'
elif ln conf$$.file conf$$ 2>/dev/null; then
as_ln_s=ln
else
as_ln_s='cp -p'
as_ln_s='cp -pR'
fi
else
as_ln_s='cp -p'
as_ln_s='cp -pR'
fi
rm -f conf$$ conf$$.exe conf$$.dir/conf$$.file conf$$.file
rmdir conf$$.dir 2>/dev/null
......@@ -503,28 +543,8 @@ else
as_mkdir_p=false
fi
if test -x / >/dev/null 2>&1; then
as_test_x='test -x'
else
if ls -dL / >/dev/null 2>&1; then
as_ls_L_option=L
else
as_ls_L_option=
fi
as_test_x='
eval sh -c '\''
if test -d "$1"; then
test -d "$1/.";
else
case $1 in #(
-*)set "./$1";;
esac;
case `ls -ld'$as_ls_L_option' "$1" 2>/dev/null` in #((
???[sx]*):;;*)false;;esac;fi
'\'' sh
'
fi
as_executable_p=$as_test_x
as_test_x='test -x'
as_executable_p=as_fn_executable_p