#!/bin/sh
# Use du to exercise a corner of fts's FTS_LOGICAL code.
# Show that du fails with ELOOP (Too many levels of symbolic links)
# when it encounters that condition.

if test "$VERBOSE" = yes; then
  set -x
  du --version
fi

. $srcdir/../lang-default

pwd=`pwd`
t0=`echo "$0"|sed 's,.*/,,'`.tmp; tmp=$t0/$$
trap 'status=$?; cd $pwd; chmod -R u+rwx $t0; rm -rf $t0 && exit $status' 0
trap '(exit $?); exit $?' 1 2 13 15

framework_failure=0
mkdir -p $tmp || framework_failure=1
cd $tmp || framework_failure=1

# Create lots of directories, each containing a single symlink
# pointing at the next directory in the list.

# This number should be larger than the number of symlinks allowed in
# file name resolution, but not too large as a number of entries
# in a single directory.
n=400

dir_list=`seq $n`
mkdir $dir_list || framework_failure=1
for i in $dir_list; do
  ip1=`expr $i + 1`
  ln -s ../$ip1 $i/s || framework_failure=1
done

if test $framework_failure = 1; then
  echo "$0: failure in testing framework" 1>&2
  (exit 1); exit 1
fi

fail=0

# With coreutils-5.93 there was no failure.
# With coreutils-5.94 we get a diagnostic like this:
# du: cannot access `1/s/s/s/.../s': Too many levels of symbolic links
du -L 1 > /dev/null 2> out1 && fail=1
sed "s,1/s/s/s/[/s]*','," out1 > out || fail=1
cat <<\EOF > exp || fail=1
du: cannot access `': Too many levels of symbolic links
EOF

cmp out exp || fail=1
test $fail = 1 && diff out exp 2> /dev/null

(exit $fail); exit $fail