1#serial 15 2# See if we need to use our replacement for Solaris' openat et al functions. 3 4dnl Copyright (C) 2004, 2005, 2006, 2007 Free Software Foundation, Inc. 5dnl This file is free software; the Free Software Foundation 6dnl gives unlimited permission to copy and/or distribute it, 7dnl with or without modifications, as long as this notice is preserved. 8 9# Written by Jim Meyering. 10 11AC_DEFUN([gl_FUNC_OPENAT], 12[ 13 AC_LIBOBJ([openat-proc]) 14 AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS]) 15 AC_CHECK_FUNCS_ONCE([lchmod]) 16 AC_CHECK_FUNCS_ONCE([fdopendir]) 17 AC_REPLACE_FUNCS([fchmodat mkdirat openat]) 18 case $ac_cv_func_openat+$ac_cv_func_lstat_dereferences_slashed_symlink in 19 yes+yes) ;; 20 yes+*) AC_LIBOBJ([fstatat]);; 21 *) 22 AC_DEFINE([__OPENAT_PREFIX], [[rpl_]], 23 [Define to rpl_ if the openat replacement function should be used.]) 24 gl_PREREQ_OPENAT;; 25 esac 26 gl_FUNC_FCHOWNAT 27]) 28 29# gl_FUNC_FCHOWNAT_DEREF_BUG([ACTION-IF-BUGGY[, ACTION-IF-NOT_BUGGY]]) 30AC_DEFUN([gl_FUNC_FCHOWNAT_DEREF_BUG], 31[ 32 AC_CACHE_CHECK([whether fchownat works with AT_SYMLINK_NOFOLLOW], 33 gl_cv_func_fchownat_nofollow_works, 34 [ 35 gl_dangle=conftest.dangle 36 # Remove any remnants of a previous test. 37 rm -f $gl_dangle 38 # Arrange for deletion of the temporary file this test creates. 39 ac_clean_files="$ac_clean_files $gl_dangle" 40 ln -s conftest.no-such $gl_dangle 41 AC_RUN_IFELSE( 42 [AC_LANG_SOURCE( 43 [[ 44#include <fcntl.h> 45#include <unistd.h> 46#include <stdlib.h> 47#include <errno.h> 48#include <sys/types.h> 49int 50main () 51{ 52 return (fchownat (AT_FDCWD, "$gl_dangle", -1, getgid (), 53 AT_SYMLINK_NOFOLLOW) != 0 54 && errno == ENOENT); 55} 56 ]])], 57 [gl_cv_func_fchownat_nofollow_works=yes], 58 [gl_cv_func_fchownat_nofollow_works=no], 59 [gl_cv_func_fchownat_nofollow_works=no], 60 ) 61 ]) 62 AS_IF([test $gl_cv_func_fchownat_nofollow_works = no], [$1], [$2]) 63]) 64 65# If we have the fchownat function, and it has the bug (in glibc-2.4) 66# that it dereferences symlinks even with AT_SYMLINK_NOFOLLOW, then 67# use the replacement function. 68# Also use the replacement function if fchownat is simply not available. 69AC_DEFUN([gl_FUNC_FCHOWNAT], 70[ 71 # Assume we'll use the replacement function. 72 # The only case in which we won't is when we have fchownat, and it works. 73 use_replacement_fchownat=yes 74 75 AC_CHECK_FUNC([fchownat], [have_fchownat=yes], [have_fchownat=no]) 76 if test $have_fchownat = yes; then 77 gl_FUNC_FCHOWNAT_DEREF_BUG([], [use_replacement_fchownat=no]) 78 fi 79 80 if test $use_replacement_fchownat = yes; then 81 AC_LIBOBJ(fchownat) 82 AC_DEFINE(fchownat, rpl_fchownat, 83 [Define to rpl_fchownat if the replacement function should be used.]) 84 fi 85]) 86 87AC_DEFUN([gl_PREREQ_OPENAT], 88[ 89 : 90]) 91