Merge pull request #13792 from benpicco/pkg/nanopb-fixes

pkg/nanopb: fix for proto files with includes

pkg/nanopb/Makefile.gensrc

@@ -2,13 +2,20 @@ PROTOC ?= protoc
 PROTOC_GEN_NANOPB ?= $(PKGDIRBASE)/nanopb/generator/protoc-gen-nanopb
 
 PROTOBUF_FILES ?= $(wildcard *.proto)
+PROTOBUF_PATH  ?= $(CURDIR)
 GENSRC   += $(PROTOBUF_FILES:%.proto=$(BINDIR)/$(MODULE)/%.pb.c)
 GENOBJC  := $(GENSRC:%.c=%.o)
 
-ifneq (, $(PROTOBUF_FILES))
+ifneq (,$(PROTOBUF_FILES))
   INCLUDES += -I$(BINDIR)/$(MODULE)
 endif
 
+# workaround for old protoc
+PROTO_INCLUDES += -I.
+# add nanopb specific includes
+PROTO_INCLUDES += -I$(PKGDIRBASE)/nanopb/generator/proto
+PROTO_INCLUDES += -I$(PROTOBUF_PATH)
+
 $(SRC): $(GENSRC)
 
 $(GENSRC): $(PROTOBUF_FILES)
@@ -18,6 +25,6 @@ $(GENSRC): $(PROTOBUF_FILES)
 		make -C $(PKGDIRBASE)/nanopb/generator/proto && \
 		for protofile in $(PROTOBUF_FILES); do \
 			protoc --plugin=protoc-gen-nanopb=$(PROTOC_GEN_NANOPB) \
-				--nanopb_out="$$D" \
+				--nanopb_out="$$D" $(PROTO_INCLUDES) \
 				$^ \
 				; done

pkg/nanopb/doc.txt

@@ -5,4 +5,12 @@
  * @brief    Provides a protocol buffers library to RIOT
  *
  * @see      https://github.com/nanopb/nanopb
+ *
+ * # Limitations
+ *
+ * The generated headers and includes from `.proto` files not accessible outside the
+ * module in which the `.proto` file is located.
+ *
+ * You can include `.proto` files that are not in the same directory by adding the
+ * directory of the `.proto` include to `PROTOBUF_PATH`.
  */

tests/pkg_nanopb/simple.proto

@@ -2,6 +2,7 @@
 // one message.
 
 syntax = "proto2";
+import "nanopb.proto";
 
 message SimpleMessage {
     required int32 lucky_number = 1;