===================================================================
RCS file: /cvs/openbsd/fw_update/fw_install.sh,v
retrieving revision 1.5
retrieving revision 1.6
diff -u -r1.5 -r1.6
--- openbsd/fw_update/fw_install.sh	2021/10/14 02:26:31	1.5
+++ openbsd/fw_update/fw_install.sh	2021/10/14 02:39:43	1.6
@@ -13,6 +13,53 @@
 	done
 }
 
+# do_as, unpriv, and unpriv2 are from install.sub
+
+# Run a command ($2+) as unprivileged user ($1).
+# Take extra care that after "cmd" no "user" processes exist.
+#
+# Optionally:
+#	- create "file" and chown it to "user"
+#	- after "cmd", chown "file" back to root
+#
+# Usage: do_as user [-f file] cmd
+do_as() {
+	(( $# >= 2 )) || return
+
+	local _file _rc _user=$1
+	shift
+
+	if [[ $1 == -f ]]; then
+		_file=$2
+		shift 2
+	fi
+
+	if [[ -n $_file ]]; then
+		>$_file
+		chown "$_user" "$_file"
+	fi
+
+	doas -u "$_user" "$@"
+	_rc=$?
+
+	while doas -u "$_user" kill -9 -1 2>/dev/null; do
+		echo "Processes still running for user $_user after: $@"
+		sleep 1
+	done
+
+	[[ -n $_file ]] && chown root "$_file"
+
+	return $_rc
+}
+
+unpriv() {
+	do_as _sndio "$@"
+}
+
+unpriv2() {
+	do_as _file "$@"
+}
+
 set -A _KERNV -- $( scan_dmesg '/^OpenBSD \([1-9][0-9]*\.[0-9]\)\([^ ]*\) .*/ { s//\1 \2/p; q; }' )
 VNAME=${_KERNV[0]}
 OSDIR=$VNAME