fiemap-2.sh

#!/bin/sh
# Exercise a few more corners of the fiemap-copying code.

# Copyright (C) 2011-2019 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 <https://www.gnu.org/licenses/>.

. "${srcdir=.}/tests/init.sh"; path_prepend_ ./src
print_ver_ cp

# Require a fiemap-enabled FS.
touch fiemap_chk # check a file rather than current dir for best coverage
fiemap_capable_ fiemap_chk \
  || skip_ "this file system lacks FIEMAP support"

# Exercise the code that handles a file ending in a hole.
printf x > k || framework_failure_
dd bs=1k seek=128 of=k < /dev/null || framework_failure_

# The first time through the outer loop, the input file, K, ends with a hole.
# The second time through, we append a byte so that it does not.
for append in no yes; do
  test $append = yes && printf y >> k
  for i in always never; do
    cp --sparse=$i k k2 || fail=1
    cmp k k2 || fail=1
  done
done

# Ensure that --sparse=always can restore holes.
rm -f k
# Create a file starting with an "x", followed by 256K-1 0 bytes.
printf x > k || framework_failure_
dd bs=1k seek=1 of=k count=255 < /dev/zero || framework_failure_

# cp should detect the all-zero blocks and convert some of them to holes.
# How many it detects/converts currently depends on io_blksize.
# Currently, on my F14/ext4 desktop, this K starts off with size 256KiB,
# (note that the K in the preceding test starts off with size 4KiB).
# cp from coreutils-8.9 with --sparse=always reduces the size to 32KiB.
cp --sparse=always k k2 || fail=1
test $(stat -c %b k2) -lt $(stat -c %b k) || fail=1

Exit $fail