oxenstored: generate a paths module

That file includes all paths generated by configure. It will be used to
get rid of hard-coded paths in code.

Signed-off-by: Wei Liu <wei.liu2@citrix.com>
Acked-by: David Scott <dave@recoil.org>

.gitignore

@@ -347,6 +347,7 @@ tools/ocaml/libs/xentoollog/xentoollog.ml
 tools/ocaml/libs/xentoollog/xentoollog.mli
 tools/ocaml/xenstored/oxenstored
 tools/ocaml/xenstored/oxenstored.conf
+tools/ocaml/xenstored/paths.ml
 tools/ocaml/test/xtl
 tools/ocaml/test/send_debug_keys
 tools/ocaml/test/list_domains

tools/ocaml/Makefile.rules

@@ -95,3 +95,14 @@ $(foreach lib,$(OCAML_LIBRARY),$(eval $(call OCAML_LIBRARY_template,$(lib))))
 $(foreach lib,$(OCAML_NOC_LIBRARY),$(eval $(call OCAML_NOC_LIBRARY_template,$(lib))))
 $(foreach p,$(OCAML_PROGRAM),$(eval $(call OCAML_PROGRAM_template,$(p))))
 $(foreach p,$(C_PROGRAM),$(eval $(call C_PROGRAM_template,$(p))))
+
+buildmakevars2module = $(eval $(call buildmakevars2module-closure,$(1)))
+define buildmakevars2module-closure
+    $(1): .phony
+	rm -f $(1).tmp; \
+	$(foreach var, $(BUILD_MAKE_VARS), \
+	          printf "let %s = \"%s\";;\n" \
+                      $(shell echo $(var) | tr '[:upper:]' '[:lower:]') \
+                      $($(var)) >>$(1).tmp;) \
+	$(call move-if-changed,$(1).tmp,$(1))
+endef

tools/ocaml/xenstored/Makefile

@@ -32,7 +32,8 @@ OCAML_LIBRARY += systemd
 
 LIBS_systemd += $(LDFLAGS-y)
 
-OBJS = define \
+OBJS = paths \
+	define \
 	stdext \
 	trie \
 	config \
@@ -87,3 +88,8 @@ install: all
 	$(INSTALL_DATA) oxenstored.conf $(DESTDIR)$(XEN_CONFIG_DIR)
 
 include $(OCAML_TOPLEVEL)/Makefile.rules
+
+genpath-target = $(call buildmakevars2module,paths.ml)
+$(eval $(genpath-target))
+
+GENERATED_FILES += paths.ml