1 files changed, 92 insertions, 0 deletions
diff --git a/py/mkrules.mk b/py/mkrules.mk
new file mode 100644
index 0000000000..4c1ea08332
--- /dev/null
+++ b/py/mkrules.mk
@@ -0,0 +1,92 @@
+ifneq ($(MKENV_INCLUDED),1)
+# We assume that mkenv is in the same directory as this file.
+THIS_MAKEFILE = $(lastword $(MAKEFILE_LIST))
+include $(dir $(THIS_MAKEFILE))mkenv.mk
+endif
+
+# This file expects that OBJ contains a list of all of the object files.
+# The directory portion of each object file is used to locate the source
+# and should not contain any ..'s but rather be relative to the top of the 
+# tree.
+#
+# So for example, py/map.c would have an object file name py/map.o
+# The object files will go into the build directory and mantain the same
+# directory structure as the source tree. So the final dependency will look
+# like this:
+#
+# build/py/map.o: py/map.c
+#
+# We set vpath to point to the top of the tree so that the source files
+# can be located. By following this scheme, it allows a single build rule
+# to be used to compile all .c files.
+
+vpath %.S . $(TOP)
+$(BUILD)/%.o: %.S
+	$(ECHO) "CC $<"
+	$(Q)$(CC) $(CFLAGS) -c -o $@ $<
+
+vpath %.s . $(TOP)
+$(BUILD)/%.o: %.s
+	$(ECHO) "AS $<"
+	$(Q)$(AS) -o $@ $<
+
+define compile_c
+$(ECHO) "CC $<"
+$(Q)$(CC) $(CFLAGS) -c -MD -o $@ $<
+@# The following fixes the dependency file.
+@# See http://make.paulandlesley.org/autodep.html for details.
+@cp $(@:.o=.d) $(@:.o=.P); \
+  sed -e 's/#.*//' -e 's/^[^:]*: *//' -e 's/ *\\$$//' \
+      -e '/^$$/ d' -e 's/$$/ :/' < $(@:.o=.d) >> $(@:.o=.P); \
+  rm -f $(@:.o=.d)
+endef
+
+vpath %.c . $(TOP)
+$(BUILD)/%.o: %.c
+	$(call compile_c)
+
+# The following rule uses | to create an order only prereuisite. Order only
+# prerequisites only get built if they don't exist. They don't cause timestamp
+# checkng to be performed.
+#
+# $(sort $(var)) removes duplicates
+#
+# The net effect of this, is it causes the objects to depend on the
+# object directories (but only for existance), and the object directories
+# will be created if they don't exist.
+OBJ_DIRS = $(sort $(dir $(OBJ)))
+$(OBJ): | $(OBJ_DIRS)
+$(OBJ_DIRS):
+	mkdir -p $@
+
+ifneq ($(PROG),)
+# Build a standalone executable (unix and unix-cpy do this)
+
+all: $(PROG)
+
+$(PROG): $(OBJ)
+	$(ECHO) "LINK $<"
+	$(Q)$(CC) -o $@ $(OBJ) $(LIB) $(LDFLAGS)
+ifndef DEBUG
+	$(Q)strip $(PROG)
+endif
+	$(Q)size $(PROG)
+
+clean: clean-prog
+clean-prog:
+	$(RM) -f $(PROG)
+
+.PHONY: clean-prog
+endif
+
+clean:
+	$(RM) -rf $(BUILD)
+.PHONY: clean
+
+print-cfg:
+	$(ECHO) "PY_SRC = $(PY_SRC)"
+	$(ECHO) "BUILD  = $(BUILD)"
+	$(ECHO) "OBJ    = $(OBJ)"
+.PHONY: print-cfg
+
+-include $(OBJ:.o=.P)