abuild: multiarch support

- add arch to .PKGINFO
- exit with success if package is not in arch

abuild.in

@@ -391,6 +391,10 @@ prepare_metafiles() {
 	mkdir -p "$controldir"
 	local builddate=$(date -u "+%s")
 	local size=$(du -sk | awk '{print $1 * 1024}')
+	local parch="$CARCH"
+	if [ "$arch" = "noarch" ]; then
+		parch="noarch"
+	fi
 
 	echo "# Generated by $(basename $0) $abuild_ver" >"$pkginfo"
 	if [ -n "$FAKEROOTKEY" ]; then
@@ -405,6 +409,7 @@ url = $url
 builddate = $builddate
 packager = ${PACKAGER:-"Unknown"}
 size = $size
+arch = $parch
 EOF
 	local i deps
 	deps="$depends"
@@ -727,6 +732,11 @@ srcpkg() {
 	(cd .. && tar -zcf "$PKGDEST/$p.src.tar.gz" $files) 
 }
 
+# return true if arch is supported or noarch
+check_arch() {
+	list_has $CARCH $arch || list_has noarch $arch
+}
+
 # check if package is up to date
 apk_up2date() {
 	getpkgver || return 1
@@ -763,6 +773,7 @@ abuildindex_up2date() {
 }
 
 up2date() {
+	check_arch || return 0
 	apk_up2date && abuildindex_up2date
 }
 
@@ -1049,6 +1060,7 @@ uninstalldeps (){
 }
 
 all() {
+	check_arch || return 0
 	if up2date && [ -z "$force" ]; then
 		msg "Package is up to date"
 	else