Cache the last successful build git commit hash

Teach `bin/ci.sh` to cache the git commit hash of the last successful
build.  Use the cached hash to determine whether building is even
necessary.  This feature introduces a new variable, `HBSD_CACHEDIR`, to
use as cache storage for the build.

Introduce `bin/cleanup.sh`. This script isn't even close to being
complete.
Signed-off-by: Shawn Webb <shawn.webb@hardenedbsd.org>

bin/ci.sh

@@ -60,18 +60,27 @@ main() {
 	config_set_dynamic
 
 	(
-		assert_unlocked && \
-		    lock_build && \
-		    update_codebase && \
-		    clean_build && \
+		assert_unlocked && lock_build
+
+		update_codebase || exit ${?}
+
+		if ! should_build; then
+			unlock_build
+			exit 0
+		fi
+
+		clean_build && \
 		    build_hardenedbsd && \
 		    build_release && \
 		    stage_release && \
 		    sign_release && \
 		    publish_release && \
 		    kick_publisher_tires && \
+		    cache_codebase_hashish && \
 		    unlock_build
+		exit ${?}
 	) | build_log 2>&1
+
 	return ${?}
 }
 

bin/cleanup.sh

+#!/bin/sh
+#-
+# Copyright (c) 2019 HardenedBSD
+# Author: Shawn Webb <shawn.webb@hardenedbsd.org>
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions
+# are met:
+# 1. Redistributions of source code must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+# 2. Redistributions in binary form must reproduce the above copyright
+#    notice, this list of conditions and the following disclaimer in the
+#    documentation and/or other materials provided with the distribution.
+#
+# THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+# ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+# IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+# ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+# FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+# DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+# OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+# HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+# LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+# OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+# SUCH DAMAGE.
+
+get_topdir() {
+	local self
+
+	self=${1}
+
+	echo $(realpath $(dirname ${self}))
+	return ${?}
+}
+
+TOPDIR=$(get_topdir ${0})
+
+. ${TOPDIR}/../lib/build.sh
+. ${TOPDIR}/../lib/config.sh
+. ${TOPDIR}/../lib/log.sh
+. ${TOPDIR}/../lib/publish.sh
+. ${TOPDIR}/../lib/util.sh
+
+main() {
+	local self
+
+	self=${0}
+	shift
+
+	config_set_defaults
+
+	while getopts 'c:' o; do
+		case "${o}" in
+			c)
+				. ${OPTARG}
+				;;
+		esac
+	done
+
+	# TODO: provide our own version of config_set_dynamic
+	config_set_dynamic
+
+	(
+		assert_unlocked && \
+		    lock_build && \
+		    prune_old_builds && \
+		    unlock_build
+	) | build_log 2>&1
+	return ${?}
+}
+
+main ${0} $*
+exit ${?}

lib/build.sh

@@ -120,10 +120,7 @@ stage_release() {
 		fi
 	done
 
-	(
-		cd ${HBSD_SRC}
-		git rev-parse HEAD > ${HBSD_STAGEDIR}/revision.txt
-	)
+	codebase_hashish > ${HBSD_STAGEDIR}/revision.txt
 
 	return 0
 }

lib/config.sh

@@ -38,6 +38,8 @@ config_set_defaults() {
 	HBSD_TARGET_ARCH=amd64
 	HBSD_NOCLEAN="-DNO_CLEAN"
 	HBSD_LOGDIR=/build/logs/13-current.amd64
+	HBSD_KEEP_NBUILDS=10
+	HBSD_CACHEDIR=/build/cache/13-current.amd64
 
 	# Set by config file, contains potentially sensitive data
 	HBSD_MIRROR_MASTER=""

lib/publish.sh

@@ -30,9 +30,16 @@ publish_release() {
 }
 
 kick_publisher_tires() {
+	local res
+
 	[ -z "${HBSD_MIRROR_MASTER}" ] && return 0
 
 	rsync -a ${HBSD_PUBDIR}/${HBSD_BUILDNUMBER}/ \
 	    ${HBSD_MIRROR_MASTER}:${HBSD_MIRROR_PUBDIR}/build-${HBSD_BUILDNUMBER}
+	res=${?}
+	if [ ${res} -gt 0 ]; then
+		return ${res}
+	fi
+
 	return ${?}
 }

lib/util.sh

@@ -66,6 +66,20 @@ build_number() {
 	return 0
 }
 
+codebase_hashish() {
+	(
+		cd ${HBSD_SRC}
+		git rev-parse HEAD
+		exit ${?}
+	)
+	return ${?}
+}
+
+cache_codebase_hashish() {
+	codebase_hashish > ${HBSD_CACHEDIR}/last_build.txt
+	return ${?}
+}
+
 update_codebase() {
 	(
 		set -ex
@@ -75,3 +89,38 @@ update_codebase() {
 	)
 	return ${?}
 }
+
+should_build() {
+	local lastbuild
+	local currenthashish
+
+	if [ ! -f ${HBSD_CACHEDIR}/last_build.txt ]; then
+		return 0
+	fi
+
+	lastbuild=$(cat ${HBSD_CACHEDIR}/last_build.txt)
+	currenthashish=$(codebase_hashish)
+
+	if [ "${lastbuild}" = "${currenthashish}" ]; then
+		return 1
+	fi
+
+	return 0
+}
+
+prune_old_builds() {
+	[ ${HBSD_BUILDNUMBER} -lt ${HBSD_KEEP_NBUILDS} ] && return 0
+
+	return 0
+
+	floor=$((${HBSD_BUILDNUMBER} - ${HBSD_KEEP_NBUILDS}))
+
+	for d in $(find ${HBSD_PUBDIR} -maxdepth 1 -type d | sed 1d); do
+		n=$(basename ${d})
+		if [ ${n} -lt ${floor} ]; then
+			rm -rf ${d}
+		fi
+	done
+
+	return 0
+}