btrfs-progs/tests/mkfs-tests/004-rootdir-keeps-size/test.sh

#!/bin/bash
# make sure that mkfs.btrfs --rootsize does not change size of the image

source "$TEST_TOP/common" || exit

check_prereq mkfs.btrfs

prepare_test_dev

test_mkfs_with_size() {
	local size
	local imgsize
	local tmp

	size="$1"
	run_check truncate -s"$size" "$TEST_DEV"
	imgsize=$(run_check_stdout stat --format=%s "$TEST_DEV")
	run_check_mkfs_test_dev --rootdir "$INTERNAL_BIN/Documentation"
	tmp=$(run_check_stdout stat --format=%s "$TEST_DEV")
	if ! [ "$imgsize" = "$tmp" ]; then
		_fail "image size changed from $imgsize to $tmp"
	fi
}

test_mkfs_with_size 128M
test_mkfs_with_size 256M
test_mkfs_with_size 512M
test_mkfs_with_size 1G
test_mkfs_with_size 2G