#!/bin/sh
# Test whether sort avoids opening more file descriptors than it is
# allowed when merging files.

# Copyright (C) 2009 Free Software Foundation, Inc.

# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.

# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.

# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

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

. $srcdir/test-lib.sh
require_ulimit_

mkdir in err || framework_failure

fail=0

for i in `seq 17`; do
  echo $i >in/$i
done

# When these tests are run inside the automated testing framework, they
# have one less available file descriptor than when run outside the
# automated testing framework. If a test with a batch size of b fails
# inside the ATF, then the same test with batch size b+1 may pass outside
# the ATF but fail inside it.

# The default batch size (nmerge) is 16.
(ulimit -n 19 \
   && sort -m --batch-size=16 in/* 2>err/merge-default-err \
   || ! grep "open failed" err/merge-default-err) || fail=1

# If sort opens a file (/dev/urandom) to sort by random hashes of keys,
# it needs to consider this file against its limit on open file
# descriptors.
(ulimit -n 20 \
   && sort -mR --batch-size=16 in/* 2>err/merge-random-err \
   || ! grep "open failed" err/merge-random-err) || fail=1

Exit $fail