+
+# external nodes and links
+#
+ALL_LINKS := $(LINKS) $(patsubst L/%,%,$(filter L/%,$(MAKECMDGOALS)))
+EXTERNAL_LINKS := $(filter $(foreach host,$(EXTERNAL_HOSTS),%-$(host)),$(ALL_LINKS))
+
+$(foreach host,$(EXTERNAL_HOSTS),sshcheck-$(host)): ;
+$(foreach host,$(EXTERNAL_HOSTS),ovsversion-$(host)): ;
+$(foreach host,$(EXTERNAL_HOSTS),showdpid-$(host)): ;
+$(foreach host,$(EXTERNAL_HOSTS),showmac-$(host)): ;
+$(foreach host,$(EXTERNAL_HOSTS),showports-$(host)): ;
+$(foreach host,$(EXTERNAL_HOSTS),update-$(host)): ;
+$(foreach host,$(EXTERNAL_HOSTS),del-controller-$(host)): ;
+$(foreach host,$(EXTERNAL_HOSTS),cache/status.$(host)): ;
+$(foreach host,$(EXTERNAL_HOSTS),cache/controller.$(host)): ;
+
+$(foreach host,$(EXTERNAL_HOSTS),cache/rsnap.ip.$(host)): ;
+ @touch $@
+
+$(foreach host,$(EXTERNAL_HOSTS),cache/rsnap.links.$(host)): ;
+ @touch $@
+
+$(foreach host,$(EXTERNAL_HOSTS),cache/db.$(host)):
+ @touch $@
+
+$(foreach host,$(EXTERNAL_HOSTS),del-db.$(host)): del-db.%:
+ @rm cache/db.$*
+
+$(foreach host,$(EXTERNAL_HOSTS),cache/switch.$(host)): ;
+ @touch $@
+
+$(foreach host,$(EXTERNAL_HOSTS),del-switch.$(host)): del-switch.%:
+ @rm -f cache/switch.$* \
+ cache/port.$*$(SEP)*@1 cache/port.*$(SEP)$*@2 \
+ cache/endpoint.$*$(SEP)*@2 cache/endpoint.*$(SEP)$*@1 \
+ L/$*$(SEP)* L/*$(SEP)$* \
+ cache/controller.$*
+
+.SECONDEXPANSION:
+
+$(foreach host,$(EXTERNAL_HOSTS),cache/bridge.$(host)): cache/bridge.%: | cache/db.%
+ @echo "Creating fake bridge on external host $(call display,$*)"
+ @touch $@
+
+$(foreach link,$(EXTERNAL_LINKS),cache/iface.$(link)@2): cache/iface.%: cache/bridge.$$(call get,%) | cache/db.$$(call get,%)
+ @echo "Creating fake interface for link $(call linkpart,$*) on external host $(call get,$*)"
+ @touch $@
+
+$(foreach link,$(EXTERNAL_LINKS),cache/port.$(link)@2): cache/port.%: cache/iface.% cache/switch.$$(call get,%)
+ @echo "Getting port number for link $(call linkpart,$(*F)) on external host $(call display,$(call get,$(*F)))"
+ @echo $(call default,EXTERNAL_PORT,$(call rightnode,$*)) > $@
+
+
+$(foreach link,$(EXTERNAL_LINKS),del-iface.$(link)@2): del-iface.%: | cache/db.$$(call get,%)
+ @echo "Removing fake interface for link $(call linkpart,$*) from external host $(call get,$*)"
+ @rm -f cache/iface.$* \
+ cache/port.$* cache/endpoint.$* cache/endpoint.$(call opp,$*) \
+ L/$(call linkpart,$*)
+
+$(foreach host,$(EXTERNAL_HOSTS),del-bridge.$(host)): del-bridge.%: | cache/db.%
+ @echo "Deleting fake bridge on external host $(call display,$*)"
+ @rm -f cache/bridge.$* \
+ cache/iface.$*$(SEP)*@1 cache/iface.*$(SEP)$*@2 \
+ cache/port.$*$(SEP)*@1 cache/port.*$(SEP)$*@2 \
+ cache/endpoint.$*$(SEP)*@? cache/endpoint.*$(SEP)$*@? \
+ L/$*$(SEP)* L/*$(SEP)$* \
+ cache/controller.$*
+
+$(foreach link,$(EXTERNAL_LINKS),ping-$(call get,$(link)@2)$(SEP)$(call get,$(link)@1)): ping-%: FORCE
+ @echo "Test from external host $(call get,$*@1) to $(call get,$*@2) skipped"
+
+# we assume that a program called tunproxy is available on the
+# external nodes.
+$(foreach link,$(EXTERNAL_LINKS),cache/endpoint.$(link)@2): cache/endpoint.%@2: cache/port.%@1 cache/host.$$(call leftnode,%)
+ @#echo $* [$<] [$^] $(call rightnode,$*)
+ @echo "===>" $(call rightnode,$*): \
+ ./tunproxy -t $$(cat cache/host.$(call leftnode,$*)):$$(cat cache/port.$*@1) \
+ -p $(call default,EXTERNAL_PORT,$(call rightnode,$*)) -e -d
+
+# reporting
+.PHONY: report
+report:
+ @echo SHELL=$(SHELL)
+ @echo "===> Configuration ($(CONF)):"
+ @cat $(CONF)
+ @for f in log/*; do \
+ echo "===> Log file $$(basename $$f):"; \
+ cat $$f; \
+ done