Makefile: place defaults values and macro defs in a separate folder
Although there are not many variable default values and macros
definitions, for modularity and scalability, place these two into a
separate folder.
Change-Id: If916a69edda07aaeaa77d60ce482e002effd7f9f
Signed-off-by: Leonardo Sandoval <leonardo.sandoval@linaro.org>
diff --git a/make_helpers/build_macros.mk b/make_helpers/build_macros.mk
new file mode 100644
index 0000000..0ac1505
--- /dev/null
+++ b/make_helpers/build_macros.mk
@@ -0,0 +1,30 @@
+#
+# Copyright (c) 2015-2020, ARM Limited and Contributors. All rights reserved.
+#
+# SPDX-License-Identifier: BSD-3-Clause
+#
+
+# Convenience function for adding build definitions
+# $(eval $(call add_define,BAR_DEFINES,FOO)) will have:
+# -DFOO if $(FOO) is empty; -DFOO=$(FOO) otherwise
+# inside the BAR_DEFINES variable.
+define add_define
+$(1) += -D$(2)$(if $(value $(2)),=$(value $(2)),)
+endef
+
+# Convenience function for verifying option has a boolean value
+# $(eval $(call assert_boolean,FOO)) will assert FOO is 0 or 1
+define assert_boolean
+$(and $(patsubst 0,,$(value $(1))),$(patsubst 1,,$(value $(1))),$(error $(1) must be boolean))
+endef
+
+# CREATE_SEQ is a recursive function to create sequence of numbers from 1 to
+# $(2) and assign the sequence to $(1)
+define CREATE_SEQ
+$(if $(word $(2), $($(1))),\
+ $(eval $(1) += $(words $($(1))))\
+ $(eval $(1) := $(filter-out 0,$($(1)))),\
+ $(eval $(1) += $(words $($(1))))\
+ $(call CREATE_SEQ,$(1),$(2))\
+)
+endef