switch to bwrap, add skipsetup, don't hardcode 'user'

build

@@ -1,13 +1,17 @@
 #!/bin/sh
+
 set -e
 [ -d cache ] || mkdir cache
-SPAWN="systemd-nspawn -M gentoolooqsbuilder -D gentoo --bind=$(realpath ./out):/out --bind=$(realpath scripts):/scripts --bind=$(realpath cache):/var/cache/distfiles"
-export UNPRIVUSER="user"
 
+SPAWN="bwrap --bind gentoo / --dev /dev --proc /proc --perms 1777 --tmpfs /dev/shm --ro-bind /etc/resolv.conf /etc/resolv.conf --bind $(realpath ./out) /out --bind $(realpath scripts) /scripts --bind $(realpath cache) /var/cache/distfiles "
+export UNPRIVUSER=$(id -n -u 1000)
+
+if [ "$1" != "skipsetup" ] ; then
 su $UNPRIVUSER -c ./scripts/1-create.sh
 ./scripts/2-create.sh
 ${SPAWN} /scripts/3-setup-gentoo.sh
 chown "$UNPRIVUSER" -R out
+fi
 ${SPAWN} su - builder -c /scripts/4-build-looqs.sh
 chown "$UNPRIVUSER" -R out
 su $UNPRIVUSER -c "cd $(pwd); ./scripts/5-bundle.sh"