+## We work in terms of `zonesets'. Each one corresponds to a Lisp source
+## file to be passed to `zone'. A zoneset has a number of different nets
+## associated with it, in the variable zoneset_NETS, and we must run it
+## through `zone' once for each net. The zoneset will make a number of
+## zones, listed in zoneset_ZONES.
+ZONESETS =
+
+###--------------------------------------------------------------------------
+### The distorted.org.uk zones.
+
+ZONESETS += distorted
+
+distorted_VIEWS = inet fretwank
+distorted_inet_NETS = inet
+distorted_fretwank_NETS = fretwank
+
+distorted_all_ZONES = distorted.org.uk io.distorted.org.uk
+distorted_fretwank_ZONES = 199.29.172.in-addr.arpa
+
+###--------------------------------------------------------------------------
+### The harlequin.org.uk zones.
+
+ZONESETS += harlequin
+
+harlequin_VIEWS = inet fretwank
+harlequin_inet_NETS = inet
+harlequin_fretwank_NETS = fretwank
+
+harlequin_all_ZONES = harlequin.org.uk
+
+###--------------------------------------------------------------------------
+### Zone construction machinery.
+
+ZONE = zone
+V_ZONE = $(call v_tag,ZONE)$(ZONE)
+
+.SECONDEXPANSION: #sorry
+
+## For each net/zoneset pair, we make a stamp file net/zoneset.stamp to
+## remember that we've made the corresponding zones.
+ALL_ZONESTAMPS = $(foreach s,$(ZONESETS), \
+ $(patsubst %,%/$s.zonestamp,$($s_VIEWS)))
+$(ALL_ZONESTAMPS) : %.zonestamp : $$(notdir $$*).lisp hosts.lisp
+ $(V_AT)mkdir -p $(dir $*)
+ $(V_ZONE) -d$(dir $*) -fview/$(call dir-nosl,$*)$(hack \
+ hack) $(addprefix -s, $($(notdir $*)_$(call dir-nosl,$*)_NETS)) $<
+ $(V_AT)touch $@
+all: $(ALL_ZONESTAMPS)
+CLEANFILES += $(sort $(foreach s,$(ZONESETS), \
+ $(foreach v,$($s_VIEWS), \
+ $v/*.zonestamp $v/*.zone)))
+REALCLEANFILES += $(sort $(foreach s,$(ZONESETS), \
+ $(foreach v,$($s_VIEWS), \
+ $v/*.serial)))
+REALCLEANDIRS += $(sort $(foreach s,$(ZONESETS),$($s_VIEWS)))
+
+## Now explain that each generated zone file depends on the corresponding
+## zonestamp. This is where things start getting a little hairy.
+$(foreach s,$(ZONESETS), \
+ $(foreach v,$($s_VIEWS), \
+ $(foreach z,$($s_all_ZONES) $($s_$v_ZONES), \
+ $(eval $v/$z.zone: $v/$s.zonestamp))))
+
+## Now we have to check the individual zone files.
+ALL_ZONECHECKS = $(foreach s,$(ZONESETS), \
+ $(foreach v,$($s_VIEWS), \
+ $(foreach z,$($s_all_ZONES) $($s_$v_ZONES), \
+ $v/$z.check)))
+$(ALL_ZONECHECKS) : %.check : %.zone
+ $(call v_tag,CHECK)\
+ { $(CHECKZONE) $(notdir $*) $^ || kill $$$$; } | \
+ { grep -Ev 'loaded serial|OK' || :; }
+check: $(ALL_ZONECHECKS)
+.PHONY: check $(ALL_ZONECHECKS)
+
+## Files to clean.
+clean:
+ rm -f $(CLEANFILES)
+ [ "$(CLEANDIRS)x" = x ] || rmdir $(CLEANDIRS) || :
+realclean:
+ rm -f $(REALCLEANFILES)
+ [ "$(REALCLEANDIRS)x" = x ] || rmdir $(REALCLEANDIRS) || :
+.PHONY: clean realclean
+
+###----- That's all, folks --------------------------------------------------