#!/bin/bash
#
# Common routines for all tests
#

_fail()
{
	echo "$*" | tee -a $RESULTS
	exit 1
}

# log a message to the results file
_log()
{
	echo "$*" | tee -a $RESULTS
}

_not_run()
{
	echo "    [NOTRUN] $*"
	exit 0
}

run_check()
{
	echo "############### $@" >> $RESULTS 2>&1
	"$@" >> $RESULTS 2>&1 || _fail "failed: $@"
}

# same as run_check but the stderr+stdout output is duplicated on stdout and
# can be processed further
run_check_stdout()
{
	echo "############### $@" >> $RESULTS 2>&1
	"$@" 2>&1 | tee -a $RESULTS || _fail "failed: $@"
}

# same as run_check but does not fail the test, output is logged
run_mayfail()
{
	echo "############### $@" >> $RESULTS 2>&1
	"$@" >> $RESULTS 2>&1 || _log "failed (ignored): $@"
}

check_prereq()
{
	if ! [ -f $TOP/$1 ]; then
		_fail "Failed prerequisities: $1";
	fi
}

check_image()
{
	local image

	image=$1
	echo "testing image $(basename $image)" >> $RESULTS
	$TOP/btrfs check $image >> $RESULTS 2>&1
	[ $? -eq 0 ] && _fail "btrfs check should have detected corruption"

	run_check $TOP/btrfs check --repair $image
	run_check $TOP/btrfs check $image
}

# Process all image dumps in a given directory,
# - raw btrfs filesystem images, suffix .raw
# - dtto compressed by XZ, suffix .raw.xz
# - meta-dump images with suffix .img
# - dtto compressed by XZ, suffix .img.xz
check_all_images()
{
	dir=$1
	for image in $(find $dir \( -iname '*.img' -o	\
				-iname '*.img.xz' -o 	\
				-iname '*.raw' -o 	\
				-iname '*.raw.xz' \) | sort)
	do
		cleanme=
		case "$image" in
		*.img)
			rm -f $image.restored
			: ;;
		*.img.xz)
			xz --decompress --keep "$image" || \
				_fail "failed to decompress image $image"
			image=${image%%.xz}
			rm -f $image.restored
			cleanme=$image
			;;
		*.raw)
			cp --sparse=auto $image $image.restored
			;;
		*.raw.xz)
			xz --decompress --keep "$image" || \
				_fail "failed to decompress image $image"
			image=${image%%.xz}
			mv "$image" "$image".restored
			;;
		esac

		if ! [ -f $image.restored ]; then
			echo "restoring image $(basename $image)" >> $RESULTS
			$TOP/btrfs-image -r $image $image.restored || \
				_fail "failed to restore image $image"
		fi

		check_image $image.restored

		rm -f $image.restored $cleanme
	done
}

# some tests need to mount the recovered image and do verifications call
# 'setup_root_helper' and then check for have_root_helper == 1 if the test
# needs to fail otherwise; using sudo by default for now
SUDO_HELPER=
NEED_SUDO_VALIDATE=unknown
export SUDO_HELPER
export NEED_SUDO_VALIDATE
root_helper()
{
	if [ $UID -eq 0 ]; then
		"$@"
	else
		if [ "$NEED_SUDO_VALIDATE" = 'yes' ]; then
			sudo -v -n &>/dev/null || \
				_not_run "Need to validate sudo credentials"
			sudo -n "$@"
		elif [ "$NEED_SUDO_VALIDATE" = 'no' ]; then
			sudo -n /bin/true &> /dev/null || \
				_not_run "Need to validate sudo user settings"
			sudo -n "$@"
		else
			# should not happen
			_not_run "Need to validate root privileges"
		fi
	fi
}

setup_root_helper()
{
	if [ $UID -eq 0 ]; then
		return
	fi

	# Test for old sudo or special settings, which make sudo -v fail even
	# if user setting is NOPASSWD
	sudo -n /bin/true &>/dev/null && NEED_SUDO_VALIDATE=no

	# Newer sudo or default sudo setting
	sudo -v -n &>/dev/null && NEED_SUDO_VALIDATE=yes

	if [ "$NEED_SUDO_VALIDATE" = 'unknown' ]; then
		_not_run "Need to validate root privileges"
	fi
	SUDO_HELPER=root_helper
}

prepare_test_dev()
{
	# num[K/M/G/T...]
	local size="$1"

	[[ "$TEST_DEV" ]] && return
	[[ "$size" ]] || size='1G'

	echo "\$TEST_DEV not given, use $TOP/test/test.img as fallback" >> \
		$RESULTS
	TEST_DEV="$TOP/tests/test.img"

	truncate -s "$size" "$TEST_DEV" || _not_run "create file for loop device failed"
}

run_check_mount_test_dev()
{
	setup_root_helper

	local loop_opt
	if [[ -b "$TEST_DEV" ]]; then
		loop_opt=""
	elif [[ -f "$TEST_DEV" ]]; then
		loop_opt="-o loop"
	else
		_fail "Invalid \$TEST_DEV: $TEST_DEV"
	fi

	[[ -d "$TEST_MNT" ]] || {
		_fail "Invalid \$TEST_MNT: $TEST_MNT"
	}

	run_check $SUDO_HELPER mount $loop_opt "$@" "$TEST_DEV" "$TEST_MNT"
}

run_check_umount_test_dev()
{
	setup_root_helper
	run_check $SUDO_HELPER umount "$@" "$TEST_DEV"
}

init_env()
{
	TEST_MNT="${TEST_MNT:-$TOP/tests/mnt}"
	export TEST_MNT
	mkdir -p "$TEST_MNT" || { echo "Failed mkdir -p $TEST_MNT"; exit 1; }
}
init_env
