Merge branch 'feat-nanopb' into 'dev'

feat: nanopb

See merge request blik/embedded/zephyr!23

Author: Tobias Aschenbrenner

samples/nanopb/CMakeLists.txt

@@ -0,0 +1,25 @@
+include($ENV{ZEPHYR_BASE}/cmake/app/boilerplate.cmake NO_POLICY_SCOPE)
+project(NONE)
+
+# Extend zephyrs minimal stdint for missing types
+include_directories("ext/nanopb_syshdr")
+add_definitions(-DPB_SYSTEM_HEADER=\"pb_syshdr.h\")
+
+# Protobuf definitions
+add_subdirectory (ext/blik)
+
+# Generated protobufs
+include_directories("${CMAKE_CURRENT_BINARY_DIR}/ext/blik")
+
+# Make nanopb headers available
+include_directories("ext/nanopb")
+
+# Mark them as to be generated and not necessarily available right away
+set_source_files_properties(${PROTO_SRCS} ${PROTO_HDRS}
+    PROPERTIES GENERATED TRUE)
+
+# Build sample with protobuf sources
+target_sources(app PRIVATE src/main.c ${PROTO_SRCS} ${PROTO_HDRS})
+
+# Ensure to generate the protobuf files before building the sample
+add_dependencies(app blik)

samples/nanopb/README.rst

@@ -0,0 +1,25 @@
+.. _nanopb:
+
+nanopb
+###########
+
+Overview
+********
+A simple example how to use nanopb in a zephyr application.
+The code is from the nanopb sample 'cmake_relpath'.
+
+Building and Running
+********************
+
+In order to build this sample, both protobuf-compiler and python-protobuf are required on the system.
+Nanopb has to be present in ext/nanopb and can be cloned from https://github.com/nanopb/nanopb.
+
+
+Sample Output
+=============
+
+.. code-block:: console
+
+***** BOOTING ZEPHYR OS v1.11.0 - BUILD: May 22 2018 19:21:56 *****
+Your lucky number was 13!
+Your unlucky number was 42!

samples/nanopb/ext/blik/CMakeLists.txt

@@ -0,0 +1,21 @@
+cmake_minimum_required(VERSION 2.8)
+project(NONE)
+
+# NANOPB LIBRARY
+set(CMAKE_MODULE_PATH ${CMAKE_CURRENT_SOURCE_DIR}/../nanopb/extra)
+find_package(Nanopb REQUIRED)
+include_directories(${NANOPB_INCLUDE_DIRS})
+
+# Generate proto
+nanopb_generate_cpp(PROTO_SRCS PROTO_HDRS RELPATH . blik.proto sub/unlucky.proto)
+
+# Mark them as to be generated and not necessarily available right away
+set_source_files_properties(${PROTO_SRCS} ${PROTO_HDRS}
+    PROPERTIES GENERATED TRUE)
+
+# Make the source- and header files globally available
+SET(PROTO_SRCS  "${PROTO_SRCS}" CACHE INTERNAL "PROTO_SRCS")
+SET(PROTO_HDRS  "${PROTO_HDRS}" CACHE INTERNAL "PROTO_HDRS")
+
+# Create target and let it depend on generating the sources first
+add_custom_target(blik SOURCES ${PROTO_SRCS} ${PROTO_HDRS})

samples/nanopb/ext/blik/blik.proto

@@ -0,0 +1,10 @@
+// A very simple protocol definition, consisting of only
+// one message.
+syntax = "proto2";
+
+import "sub/unlucky.proto";
+
+message SimpleMessage {
+    required int32 lucky_number = 1;
+    required UnluckyNumber unlucky = 2;
+}

samples/nanopb/ext/blik/sub/unlucky.proto

@@ -0,0 +1,5 @@
+syntax = "proto2";
+
+message UnluckyNumber {
+	required uint32 number = 1;
+}

samples/nanopb/ext/nanopb_syshdr/pb_syshdr.h

@@ -0,0 +1,17 @@
+#ifndef _PB_SYSHDR_H_
+#define _PB_SYSHDR_H_
+
+#include <stdint.h>
+#include <stdbool.h>
+#include <string.h>
+#ifdef PB_ENABLE_MALLOC
+#include <stdlib.h>
+#endif
+
+/* The minimal stdint that ships with zephyr doesn't define any least types */
+typedef int8_t int_least8_t;
+typedef uint8_t uint_least8_t;
+typedef int16_t int_least16_t;
+typedef uint16_t uint_least16_t;
+
+#endif

samples/nanopb/prj.conf

@@ -0,0 +1 @@
+# nothing here

samples/nanopb/sample.yaml

@@ -0,0 +1,12 @@
+sample:
+  description: nanopb for zephyr
+    application
+  name: nanopb
+  platforms: all
+common:
+    tags: samples
+    harness: console
+    harness_config:
+      type: one_line
+      regex:
+        - "nanopb (.*)"

samples/nanopb/src/main.c

@@ -0,0 +1,72 @@
+#include <zephyr.h>
+#include <stdio.h>
+#include <pb_encode.h>
+#include <pb_decode.h>
+#include "blik.pb.h"
+
+/* This is the buffer where we will store our message. */
+static u8_t buffer[128];
+
+void main(void)
+{
+	size_t message_length;
+	bool status;
+
+	/* Encode our message */
+	{
+		/* Allocate space on the stack to store the message data.
+		 *
+		 * Nanopb generates simple struct definitions for all messages.
+		 * - check out the contents of simple.pb.h!
+		 * It is a good idea to always initialize your structures
+		 * so that you do not have garbage data from RAM in there.
+		 */
+		SimpleMessage message = SimpleMessage_init_zero;
+
+		/* Create a stream that will write to our buffer. */
+		pb_ostream_t stream = pb_ostream_from_buffer(buffer, sizeof(buffer));
+
+		/* Fill in the lucky number */
+		message.lucky_number = 13;
+		message.unlucky.number = 42;
+
+		/* Now we are ready to encode the message! */
+		status = pb_encode(&stream, SimpleMessage_fields, &message);
+		message_length = stream.bytes_written;
+
+		/* Then just check for any errors.. */
+		if (!status) {
+			printk("Encoding failed: %s\n", PB_GET_ERROR(&stream));
+			return;
+		}
+	}
+
+	/* Now we could transmit the message over network, store it in a file or
+	 * wrap it to a pigeon's leg.
+	 */
+
+	/* But because we are lazy, we will just decode it immediately. */
+
+	{
+		/* Allocate space for the decoded message. */
+		SimpleMessage message = SimpleMessage_init_zero;
+
+		/* Create a stream that reads from the buffer. */
+		pb_istream_t stream = pb_istream_from_buffer(buffer, message_length);
+
+		/* Now we are ready to decode the message. */
+		status = pb_decode(&stream, SimpleMessage_fields, &message);
+
+		/* Check for errors... */
+		if (!status) {
+			printk("Decoding failed: %s\n", PB_GET_ERROR(&stream));
+			return;
+		}
+
+		/* Print the data contained in the message. */
+		printk("Your lucky number was %d!\n", message.lucky_number);
+		printk("Your unlucky number was %u!\n", message.unlucky.number);
+	}
+
+}
+