#!/bin/bash
#
# kpatch integration test framework
#
# Copyright (C) 2014 Josh Poimboeuf <jpoimboe@redhat.com>
#
# 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 2
# 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, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA,
# 02110-1301, USA.
#
#
# This is a basic integration test framework for kpatch, which tests building,
# loading, and unloading patches, as well as any other related custom tests.
#
# This script looks for test input files in the current directory.  It expects
# certain file naming conventions:
#
# - foo.patch: patch that should build successfully
#
# - bar-FAIL.patch: patch that should fail to build
#
# - foo-LOADED.test: executable which tests whether the foo.patch module is
#   loaded.  It will be used to test that loading/unloading the patch module
#   works as expected.
#
# Any other *.test files will be executed after all the patch modules have been
# built from the *.patch files.  They can be used for more custom tests above
# and beyond the simple loading and unloading tests.

SCRIPTDIR="$(readlink -f $(dirname $(type -p $0)))"
ROOTDIR="$(readlink -f $SCRIPTDIR/../..)"
# TODO: option to use system-installed binaries instead
KPATCH="sudo $ROOTDIR/kpatch/kpatch"
RMMOD="sudo rmmod"
KPATCHBUILD="$ROOTDIR"/kpatch-build/kpatch-build
ERROR=0
LOG=test.log
rm -f $LOG

usage() {
	echo "usage: $0 [options]" >&2
	echo "		-h, --help	Show this help message" >&2
	echo "		-c, --cached	Don't rebuild patch modules" >&2
	echo "		-q, --quick	Just combine all patches into one module for testing" >&2
}

options=$(getopt -o hcq -l "help,cached,quick" -- "$@") || exit 1

eval set -- "$options"

while [[ $# -gt 0 ]]; do
	case "$1" in
	-h|--help)
		usage
		exit 0
		;;
	-c|--cached)
		SKIPBUILD=1
		;;
	-q|--quick)
		QUICK=1
		;;
	esac
	shift
done


error() {
	echo "ERROR: $@" |tee -a $LOG >&2
	ERROR=$((ERROR + 1))
}

log() {
	echo "$@" |tee -a $LOG
}

unload_all() {
	for i in `lsmod |egrep '^kpatch' |awk '{print $1}'`; do
		if [[ $i != kpatch ]]; then
			$KPATCH unload $i >> $LOG 2>&1 || error "\"kpatch unload $i\" failed"
		fi
	done
	if lsmod |egrep -q '^kpatch'; then
		$RMMOD kpatch >> $LOG 2>&1 || error "\"rmmod kpatch\" failed"
	fi
}

build_module() {
	file=$1
	prefix=${file%%.patch}
	module=kpatch-$prefix.ko

	[[ $prefix = COMBINED ]] && return

	if [[ $prefix = *-FAIL ]]; then
		shouldfail=1
	else
		shouldfail=0
	fi

	if [[ $SKIPBUILD -eq 1 ]]; then
		skip=0
		[[ $shouldfail -eq 1 ]] && skip=1
		[[ -e $module ]] && skip=1
		[[ $skip -eq 1 ]] && log "skipping build: $prefix" && return
	fi

	log "build: $prefix"

	if ! $KPATCHBUILD $file >> $LOG 2>&1; then
		[[ $shouldfail -eq 0 ]] && error "$prefix: build failed"
	else
		[[ $shouldfail -eq 1 ]] && error "$prefix: build succeeded when it should have failed"
	fi
}

run_load_test() {
	file=$1
	prefix=${file%%.patch}
	module=kpatch-$prefix.ko
	testprog=$prefix-LOADED.test

	[[ $prefix = COMBINED ]] && return
	[[ $prefix = *-FAIL ]] && return

	if [[ ! -e $module ]]; then
		log "can't find $module, skipping"
		return
	fi

	if [[ -e $testprog ]]; then
		log "load test: $prefix"
	else
		log "load test: $prefix (no test prog)"
	fi


	if ! $KPATCH replace $module >> $LOG 2>&1; then
		error "$prefix: kpatch replace failed"
		return
	fi

	if [[ -e $testprog ]] && ! ./$testprog >> $LOG 2>&1; then
		error "$prefix: $testprog failed after kpatch replace"
		return
	fi

	if ! $KPATCH unload $module >> $LOG 2>&1; then
		error "$prefix: kpatch unload failed"
		return
	fi

	if [[ -e $testprog ]] && ./$testprog >> $LOG 2>&1; then
		error "$prefix: $testprog succeeded after kpatch unload"
		return
	fi

	if ! $KPATCH load $module >> $LOG 2>&1; then
		error "$prefix: kpatch load failed"
		return
	fi

	if [[ -e $testprog ]] && ! ./$testprog >> $LOG 2>&1; then
		error "$prefix: $testprog failed after kpatch load"
		return
	fi
}

run_custom_test() {
	testprog=$1
	prefix=${file%%.test}

	[[ $testprog = *-LOADED.test ]] && return

	log "custom test: $prefix"

	if ! ./$testprog >> $LOG 2>&1; then
		error "$prefix: test failed"
	fi
}

build_combined_module() {

	if [[ $SKIPBUILD -eq 1 ]] && [[ -e kpatch-COMBINED.ko ]]; then
		log "skipping build: combined"
		return
	fi

	if ! which combinediff > /dev/null; then
		log "patchutils not installed, skipping combined module build"
		error "PLEASE INSTALL PATCHUTILS"
		return
	fi

	rm -f COMBINED.patch
	first=1
	for file in *.patch; do
		prefix=${file%%.patch}

		[[ $prefix = *-FAIL ]] && continue
		[[ $prefix = meminfo-cmdline ]] && continue # HACK

		log "combine: $prefix"

		if [[ $first -eq 1 ]]; then
			cp -f $file COMBINED.patch
			first=0
			continue
		fi

		combinediff COMBINED.patch $file > TMP.patch
		mv -f TMP.patch COMBINED.patch
	done

	log "build: combined module"

	if ! $KPATCHBUILD COMBINED.patch >> $LOG 2>&1; then
		error "combined build failed"
	fi
}

run_combined_test() {
	if [[ ! -e kpatch-COMBINED.ko ]]; then
		log "can't find kpatch-COMBINED.ko, skipping"
		return
	fi

	log "load test: combined module"

	if ! $KPATCH replace kpatch-COMBINED.ko >> $LOG 2>&1; then
		error "combined: kpatch replace failed"
		return
	fi

	for testprog in *.test; do
		[[ $testprog != *-LOADED.test ]] && continue
		if ! ./$testprog >> $LOG 2>&1; then
			error "combined: $testprog failed"
		fi
	done
}

echo "clearing printk buffer"
sudo dmesg -C

cd "$SCRIPTDIR"

if [[ $QUICK != 1 ]]; then
	for file in *.patch; do
		build_module $file
	done
fi

build_combined_module

unload_all

if [[ $QUICK != 1 ]]; then
	for file in *.patch; do
		run_load_test $file
	done
fi

run_combined_test

if [[ $QUICK != 1 ]]; then
	for file in *.test; do
		unload_all
		run_custom_test $file
	done
fi


unload_all

dmesg |grep -q "Call Trace" && error "kernel error detected in printk buffer"

if [[ $ERROR -gt 0 ]]; then
	log "$ERROR errors encountered"
	echo "see test.log for more information"
else
	log "SUCCESS"
fi

exit $ERROR