make binary exec path dynamic in scripts referring to it

Everything should just work out of the box without poking.  This change
makes that goal to be yet agian one step closer.  In same go make all
autotools related variable substitutions better.

Requested-by: Martijn van Brummelen <martijn@brumit.nl>
Signed-off-by: Sami Kerola <kerolasa@iki.fi>

Makefile.am

@@ -16,9 +16,35 @@ $(top_srcdir)/.version:
 dist-hook:
 	echo $(VERSION) > $(distdir)/.tarball-version
 
-CLEANFILES =
+PATHFILES =
+CLEANFILES = $(PATHFILES)
+EXTRA_DIST += $(PATHFILES:=.in)
 CLEAN_LOCALS =
 
+edit_cmd = sed \
+	 -e 's|@ALARM_CRIT[@]|$(ALARM_CRIT)|g' \
+	 -e 's|@ALARM_WARN[@]|$(ALARM_WARN)|g' \
+	 -e 's|@DHCPDCONF_FILE[@]|$(DHCPDCONF_FILE)|g' \
+	 -e 's|@DHCPDLEASE_FILE[@]|$(DHCPDLEASE_FILE)|g' \
+	 -e 's|@OUTPUT_FORMAT[@]|$(OUTPUT_FORMAT)|g' \
+	 -e 's|@OUTPUT_LIMIT[@]|$(OUTPUT_LIMIT)|g' \
+	 -e 's|@PACKAGE_BUGREPORT[@]|$(PACKAGE_BUGREPORT)|g' \
+	 -e 's|@PACKAGE_MAINTAINER[@]|$(PACKAGE_MAINTAINER)|g' \
+	 -e 's|@PACKAGE_NAME[@]|$(PACKAGE_NAME)|g' \
+	 -e 's|@PACKAGE_URL[@]|$(PACKAGE_URL)|g' \
+	 -e 's|@SHELL[@]|$(SHELL)|g' \
+	 -e 's|@VERSION[@]|$(VERSION)|g' \
+	 -e 's|@bindir[@]|$(bindir)|g' \
+	 -e 's|@top_srcdir[@]|$(top_srcdir)|g'
+
+$(PATHFILES): Makefile
+	@ rm -f $@ $@.tmp
+	$(AM_V_at) test -d $(dir $@) || mkdir -p $(dir $@)
+	$(AM_V_GEN) srcdir=''; \
+		test -f ./$@.in || srcdir=$(srcdir)/; \
+		$(edit_cmd) $${srcdir}$@.in >$@.tmp
+	@ mv $@.tmp $@
+
 include contrib/Makemodule.am
 include doc/Makemodule.am
 include man/Makemodule.am