#!/bin/bash
# umoci: Umoci Modifies Open Containers' Images
# Copyright (C) 2016-2020 SUSE LLC
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#   http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

set -u
source "$(dirname "$BASH_SOURCE")/../hack/readlinkf.sh"

# Root directory of integration tests.
INTEGRATION_ROOT=$(dirname "$(readlinkf_posix "$BASH_SOURCE")")

# Binary paths.
UMOCI="${UMOCI:-${INTEGRATION_ROOT}/../umoci}"
# For some reason $(whence ...) and $(where ...) are broken.
RUNC="/usr/bin/runc"
GOMTREE="/usr/bin/gomtree"

# The source OCI image path, which we will make a copy of for each test.
SOURCE_IMAGE="${SOURCE_IMAGE:-/image}"
SOURCE_TAG="${SOURCE_TAG:-latest}"

# We need to store the coverage outputs somewhere.
COVERAGE_DIR="${COVERAGE_DIR:-}"

# Are we rootless?
IS_ROOTLESS="$(id -u)"

# Let's not store everything in /tmp -- that would just be messy.
TESTDIR_TMPDIR="$BATS_TMPDIR/umoci-integration"
mkdir -p "$TESTDIR_TMPDIR"

# Stores the set of tmpdirs that still have to be cleaned up. Calling
# teardown_tmpdirs will set this to an empty array (and all the tmpdirs
# contained within are removed).
export TESTDIR_LIST="$(mktemp "$TESTDIR_TMPDIR/umoci-integration-tmpdirs.XXXXXX")"

# INVALID_TAG is a sample invalid tag as per the OCI spec.
INVALID_TAG=".AZ94n18s"

# setup_tmpdir creates a new temporary directory and returns its name.  Note
# that if "$IS_ROOTLESS" is true, then removing this tmpdir might be harder
# than expected -- so tests should not really attempt to clean up tmpdirs.
function setup_tmpdir() {
	[[ -n "${UMOCI_TMPDIR:-}" ]] || UMOCI_TMPDIR="$TESTDIR_TMPDIR"
	mktemp -d "$UMOCI_TMPDIR/umoci-integration-tmpdir.XXXXXXXX" | tee -a "$TESTDIR_LIST"
}

# setup_tmpdirs just sets up the "built-in" tmpdirs.
function setup_tmpdirs() {
	declare -g UMOCI_TMPDIR="$(setup_tmpdir)"
}

# teardown_tmpdirs removes all tmpdirs created with setup_tmpdir.
function teardown_tmpdirs() {
	# Do nothing if TESTDIR_LIST doesn't exist.
	[ -e "$TESTDIR_LIST" ] || return

	# Remove all of the tmpdirs.
	while IFS= read tmpdir; do
		[ -e "$tmpdir" ] || continue
		chmod -R 0777 "$tmpdir"
		rm -rf "$tmpdir"
	done < "$TESTDIR_LIST"

	# Clear tmpdir list.
	rm -f "$TESTDIR_LIST"
}

# Where we're going to copy the images and bundle to.
IMAGE="$(setup_tmpdir)/image"
TAG="${SOURCE_TAG}"

# Allows a test to specify what things it requires. If the environment can't
# support it, the test is skipped with a message.
function requires() {
	for var in "$@"; do
		case $var in
			root)
				if [ "$IS_ROOTLESS" -ne 0 ]; then
					skip "test requires ${var}"
				fi
				;;
			*)
				fail "BUG: Invalid requires ${var}."
				;;
		esac
	done
}

function image-verify() {
	oci-image-tool validate --type "imageLayout" "$@"
	return $?
}

function bundle-verify() {
	args=()

	for arg in "$@"; do
		args+=( --path="$arg" )
	done

	oci-runtime-tool validate "${args[@]}"
	return $?
}

function umoci() {
	local args=()
	if [ -n "$COVERAGE_DIR" ]; then
		coverprofile="$(mktemp -p "$COVERAGE_DIR" umoci.cov.XXXXXX)"
		args+=("-test.coverprofile=${coverprofile}" "__DEVEL--i-heard-you-like-tests")
	fi

	if [[ "$1" == "raw" ]]; then
		args+=("$1")
		shift 1
	fi

	# Set the first argument (the subcommand).
	# TODO: This doesn't correctly handle any global arguments which go before
	#       the subcommand. We should probably switch to getopt here.
	args+=("$1")

	# We're rootless if we're asked to unpack something.
	if [[ "$IS_ROOTLESS" != 0 && "$1" == "unpack" ]]; then
		args+=("--rootless")
	fi

	shift
	args+=("$@")
	sane_run "$UMOCI" "${args[@]}"

	# Because this is a "go test -c" binary, we need to remove some lines from
	# the output so that it matches a regular umoci binary (and so the tests
	# make sense if you read them as an umoci user).
	#
	# TODO: Make all of this actually depend on whether it's a test binary.
	case "$status" in
		# If the test succeeded then we only need to remove two lines:
		#
		#  PASS
		#  coverage: 23.9% of statements in ./...
		0)
			lines_to_remove=2
			;;
		# However, if the test failed then "go test" will output more
		# information about the test failure:
		#
		#   open CAS: validate: read oci-layout: invalid image detected
		#   --- FAIL: TestUmoci (0.00s)
		#   FAIL
		#   coverage: 5.6% of statements in ./...
		*)
			lines_to_remove=3
			;;
	esac
	export output="$(echo "$output" | head -n "-$lines_to_remove")"
	for _ in $(seq "$lines_to_remove"); do
		unset 'lines[${#lines[@]}-1]'
	done
}

function gomtree() {
	local args=("$@")

	# We're rootless. Note that the "-rootless" flag is actually an out-of-tree
	# patch applied by openSUSE here:
	#   <https://build.opensuse.org/package/show/Virtualization:containers/go-mtree>.
	if [[ "$IS_ROOTLESS" != 0 ]]; then
		args+=("-rootless")
	fi

	sane_run "$GOMTREE" -K sha256digest "${args[@]}"
}

function runc() {
	sane_run "$RUNC" --root "$RUNC_ROOT" "$@"
}

function sane_run() {
	local cmd="$1"
	shift

	run "$cmd" "$@"

	# Some debug information to make life easier.
	echo "$(basename "$cmd") $@ (status=$status)" >&2
	echo "$output" >&2
}

function setup_image() {
	cp -r "${SOURCE_IMAGE}" "${IMAGE}"
	image-verify "${IMAGE}"

	# These are just used for diagnostics, so we ignore the status.
	sane_run df
	sane_run du -h -d 2 "$UMOCI_TMPDIR"
}

function teardown_image() {
	rm -rf "${IMAGE}"
}

function setup_runc() {
	declare -g RUNC_ROOT="$(setup_tmpdir)"
}

function is_container_dead() {
	runc state "$1"
	[ "$status" -ne 0 ] || [ "$output" =~ *stopped* ]
}

function teardown_runc() {
	for ctr in $(ls "$RUNC_ROOT" 2>/dev/null)
	do
		runc kill "$ctr" KILL
		retry 10 1 eval "is_container_dead '$ctr'"
		runc delete -f "$ctr"
	done
}

# Generate a new $BUNDLE and $ROOTFS combination.
function new_bundle_rootfs() {
	declare -g BUNDLE="$(setup_tmpdir)"
	declare -g ROOTFS="$BUNDLE/rootfs"
}

# _getfattr is a sane wrapper around getfattr(1) which only extracts the value
# of the requested xattr (and removes any of the other crap that it spits out).
# The usage is "sane_getfattr <xattr name> <path>" and outputs the hex
# representation in a single line. Exit status is non-zero if the xattr isn't
# set.
function _getfattr() {
	# We only support single-file inputs.
	[ "$#" -eq 2 ] || return 1

	local xattr="$1"
	local path="$2"

	# Run getfattr.
	(
		set -o pipefail
		getfattr -e hex -n "$xattr" "$path" 2>/dev/null \
			| grep "^$xattr=" | sed "s|^$xattr=||g"
	)
	return $?
}