makechrootpkg: check truthiness using shell arithmetic

Using the literal strings "true" and "false" is inaccurate and may
result in uncertainty of whether it is set when doing string comparison,
or simply rely on the shell implementation of treating the string as a
command builtin, then executing the value as a shell command. Emulate
makepkg, which makes heavy use of shell arithmetic for this purpose.

Signed-off-by: Eli Schwartz <eschwartz@archlinux.org>
Signed-off-by: Levente Polyak <anthraxx@archlinux.org>

makechrootpkg.in

@@ -17,17 +17,18 @@ shopt -s nullglob
 
 default_makepkg_args=(--syncdeps --noconfirm --log --holdver --skipinteg)
 makepkg_args=("${default_makepkg_args[@]}")
-keepbuilddir=false
-update_first=false
-clean_first=false
-run_namcap=false
-temp_chroot=false
 chrootdir=
 passeddir=
 makepkg_user=
 declare -a install_pkgs
 declare -i ret=0
 
+keepbuilddir=0
+update_first=0
+clean_first=0
+run_namcap=0
+temp_chroot=0
+
 bindmounts_ro=()
 bindmounts_rw=()
 
@@ -167,7 +168,7 @@ install_packages() {
 }
 
 prepare_chroot() {
-	[[ $keepbuilddir = true ]] || rm -rf "$copydir/build"
+	(( keepbuilddir )) || rm -rf "$copydir/build"
 
 	local builduser_uid builduser_gid
 	builduser_uid="${SUDO_UID:-$UID}"
@@ -206,7 +207,7 @@ EOF
 		declare -p SOURCE_DATE_EPOCH 2>/dev/null || true
 		printf '_chrootbuild "$@" || exit\n'
 
-		if [[ $run_namcap = true ]]; then
+		if (( run_namcap )); then
 			declare -f _chrootnamcap
 			printf '_chrootnamcap || exit\n'
 		fi
@@ -289,15 +290,15 @@ move_products() {
 
 while getopts 'hcur:I:l:nTD:d:U:' arg; do
 	case "$arg" in
-		c) clean_first=true ;;
+		c) clean_first=1 ;;
 		D) bindmounts_ro+=("--bind-ro=$OPTARG") ;;
 		d) bindmounts_rw+=("--bind=$OPTARG") ;;
-		u) update_first=true ;;
+		u) update_first=1 ;;
 		r) passeddir="$OPTARG" ;;
 		I) install_pkgs+=("$OPTARG") ;;
 		l) copy="$OPTARG" ;;
-		n) run_namcap=true; makepkg_args+=(--install) ;;
+		n) run_namcap=1; makepkg_args+=(--install) ;;
-		T) temp_chroot=true; copy+="-$$" ;;
+		T) temp_chroot=1; copy+="-$$" ;;
 		U) makepkg_user="$OPTARG" ;;
 		h|*) usage ;;
 	esac
@@ -326,10 +327,10 @@ makepkg_args+=("${@:$OPTIND}")
 # See if -R or -e was passed to makepkg
 for arg in "${makepkg_args[@]}"; do
 	case ${arg%%=*} in
-		--repackage|--noextract) keepbuilddir=true; break ;;
+		--repackage|--noextract) keepbuilddir=1; break ;;
-		--repackage|--noextract) keepbuilddir=true; break ;;
+		--repackage|--noextract) keepbuilddir=1; break ;;
 		--*) ;;
-		-*R*|-*e*) keepbuilddir=true; break ;;
+		-*R*|-*e*) keepbuilddir=1; break ;;
 	esac
 done
 
@@ -353,11 +354,11 @@ load_vars /etc/makepkg.conf
 # Lock the chroot we want to use. We'll keep this lock until we exit.
 lock 9 "$copydir.lock" "Locking chroot copy [%s]" "$copy"
 
-if [[ ! -d $copydir ]] || $clean_first; then
+if [[ ! -d $copydir ]] || (( clean_first )); then
 	sync_chroot "$chrootdir" "$copydir" "$copy"
 fi
 
-$update_first && arch-nspawn "$copydir" \
+(( update_first )) && arch-nspawn "$copydir" \
 		"${bindmounts_ro[@]}" "${bindmounts_rw[@]}" \
 		pacman -Syu --noconfirm
 
@@ -388,10 +389,10 @@ else
 	(( ret += 1 ))
 fi
 
-$temp_chroot && delete_chroot "$copydir" "$copy"
+(( temp_chroot )) && delete_chroot "$copydir" "$copy"
 
 if (( ret != 0 )); then
-	if $temp_chroot; then
+	if (( temp_chroot )); then
 		die "Build failed"
 	else
 		die "Build failed, check %s/build" "$copydir"