pf tests: log additional information when a test ends

Log information from the running jails (routing, interfaces and pf) as
well as interfaces on the host.

This information is expected to be useful in debugging test failures.

MFC after:	2 weeks
Sponsored by:	Rubicon Communications, LLC ("Netgate")

tests/sys/netpfil/pf/utils.subr

@@ -28,8 +28,39 @@
 
 . $(atf_get_srcdir)/../../common/vnet.subr
 
+pft_onerror()
+{
+	status=$?
+
+	echo "Debug log."
+	echo "=========="
+	echo "Test exit status: $?"
+	echo
+
+	if [ -f created_jails.lst ]; then
+		for jailname in `cat created_jails.lst`
+		do
+			echo "Jail ${jailname}"
+			echo "----------------"
+			jexec ${jailname} ifconfig
+			jexec ${jailname} netstat -rn
+			jexec ${jailname} pfctl -sa -v
+		done
+	fi
+
+	echo "Created interfaces:"
+	echo "-------------------"
+	cat created_interfaces.lst
+
+	echo "Host interfaces:"
+	echo "----------------"
+	ifconfig
+}
+
 pft_init()
 {
+	trap pft_onerror EXIT
+
 	vnet_init
 
 	if [ ! -c /dev/pf ]; then