pkg: introduce nanoPb Protocol Buffers library

Makefile.base

@@ -52,8 +52,8 @@ ifeq ($(strip $(ASSMSRC))$(NO_AUTO_SRC),)
   ASSMSRC := $(wildcard *.S)
 endif
 
-# include makefile snippets that modify GENSRC here:
-#include foo/bar.inc.mk
+# include makefile snippets for packages in $(USEPKG) that modify GENSRC:
+-include $(USEPKG:%=$(RIOTPKG)/%/Makefile.gensrc)
 
 GENOBJC     := $(GENSRC:%.c=%.o)
 OBJC_LTO    := $(SRC:%.c=$(BINDIR)/$(MODULE)/%.o)

pkg/nanopb/Makefile

@@ -0,0 +1,11 @@
+PKG_NAME=nanopb
+PKG_URL=https://github.com/nanopb/nanopb
+PKG_VERSION=493adf3616bee052649c63c473f8355630c2797f # nanopb-0.3.9.4
+PKG_LICENSE=MIT
+
+.PHONY: all
+
+all: git-download
+	"$(MAKE)" -C $(PKG_BUILDDIR) -f $(CURDIR)/Makefile.nanopb
+
+include $(RIOTBASE)/pkg/pkg.mk

pkg/nanopb/Makefile.gensrc

@@ -0,0 +1,23 @@
+PROTOC ?= protoc
+PROTOC_GEN_NANOPB ?= $(PKGDIRBASE)/nanopb/generator/protoc-gen-nanopb
+
+PROTOBUF_FILES ?= $(wildcard *.proto)
+GENSRC   += $(PROTOBUF_FILES:%.proto=$(BINDIR)/$(MODULE)/%.pb.c)
+GENOBJC  := $(GENSRC:%.c=%.o)
+
+ifneq (, $(PROTOBUF_FILES))
+  INCLUDES += -I$(BINDIR)/$(MODULE)
+endif
+
+$(SRC): $(GENSRC)
+
+$(GENSRC): $(PROTOBUF_FILES)
+	$(Q)D=$(BINDIR)/$(MODULE) && \
+	  mkdir -p "$$D" && \
+		cd $(CURDIR) && \
+		make -C $(PKGDIRBASE)/nanopb/generator/proto && \
+		for protofile in $(PROTOBUF_FILES); do \
+			protoc --plugin=protoc-gen-nanopb=$(PROTOC_GEN_NANOPB) \
+				--nanopb_out="$$D" \
+				$^ \
+				; done

pkg/nanopb/Makefile.include

@@ -0,0 +1 @@
+INCLUDES += -I$(PKGDIRBASE)/nanopb

pkg/nanopb/Makefile.nanopb

@@ -0,0 +1,3 @@
+SRCS := pb_encode.c pb_decode.c pb_common.c
+
+include $(RIOTBASE)/Makefile.base

pkg/nanopb/doc.txt

@@ -0,0 +1,8 @@
+/**
+ * @defgroup pkg_nanopb small Protocol Buffers library
+ * @ingroup  pkg
+ * @ingroup  sys
+ * @brief    Provides a protocol buffers library to RIOT
+ *
+ * @see      https://github.com/nanopb/nanopb
+ */