Nanopb is a plain-C implementation of Google's Protocol Buffers data

format. It is targeted at 32 bit microcontrollers, but is also fit for
other embedded systems with tight (2-10 kB ROM, <1 kB RAM) memory
constraints.(http://koti.kapsi.fi/jpa/nanopb/)

How to use the example:
	1. move examples/nanopb to bsp/xxxx/
	2. enable macro RT_USING_NANOPB in rtconfig.h
	3. regenerate the project file (scons --target=xxxx)
	4. rebuild the project

6 files changed, 160 insertions, 0 deletions

diff --git a/examples/nanopb/SConscript b/examples/nanopb/SConscript
new file mode 100644
index 0000000000..7c8bce9f26
--- /dev/null
+++ b/examples/nanopb/SConscript
@@ -0,0 +1,13 @@
+Import('RTT_ROOT')
+Import('rtconfig')
+from building import *
+
+src	= Split('''
+simple.c
+simple.pb.c
+''')
+CPPPATH = [RTT_ROOT + '/examples/nanopb']
+
+group = DefineGroup('Nanopb_test', src, depend = ['RT_USING_NANOPB'], CPPPATH = CPPPATH)
+
+Return('group')
\ No newline at end of file
diff --git a/examples/nanopb/simple.c b/examples/nanopb/simple.c
new file mode 100644
index 0000000000..2b793c014f
--- /dev/null
+++ b/examples/nanopb/simple.c
@@ -0,0 +1,73 @@
+#include <rthw.h>
+#include <stm32f10x.h>
+#include <pb_encode.h>
+#include <pb_decode.h>
+#include "simple.pb.h"
+
+int nanopb_test()
+{
+    /* This is the buffer where we will store our message. */
+    uint8_t buffer[128];
+    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 the messages.
+         * - check out the contents of simple.pb.h! */
+        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;
+
+        /* 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)
+        {
+            rt_kprintf("Encoding failed: %s\n", PB_GET_ERROR(&stream));
+            return 1;
+        }
+    }
+
+    /* 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;
+
+        /* 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)
+        {
+            rt_kprintf("Decoding failed: %s\n", PB_GET_ERROR(&stream));
+            return 1;
+        }
+
+        /* Print the data contained in the message. */
+        rt_kprintf("Your lucky number was %d!\n", message.lucky_number);
+    }
+
+    return 0;
+}
+
+#ifdef RT_USING_FINSH
+#include <finsh.h>
+FINSH_FUNCTION_EXPORT(nanopb_test, nanopb encode/decode test.)
+#endif
diff --git a/examples/nanopb/simple.options b/examples/nanopb/simple.options
new file mode 100644
index 0000000000..90960d0d34
--- /dev/null
+++ b/examples/nanopb/simple.options
@@ -0,0 +1 @@
+SimpleMessage.name		max_size:16
\ No newline at end of file
diff --git a/examples/nanopb/simple.pb.c b/examples/nanopb/simple.pb.c
new file mode 100644
index 0000000000..eaf09e58da
--- /dev/null
+++ b/examples/nanopb/simple.pb.c
@@ -0,0 +1,18 @@
+/* Automatically generated nanopb constant definitions */
+/* Generated by nanopb-0.3.1 at Tue Mar 10 01:16:15 2015. */
+
+#include "simple.pb.h"
+
+#if PB_PROTO_HEADER_VERSION != 30
+#error Regenerate this file with the current version of nanopb generator.
+#endif
+
+
+
+const pb_field_t SimpleMessage_fields[3] = {
+    PB_FIELD(  1, INT32   , REQUIRED, STATIC  , FIRST, SimpleMessage, lucky_number, lucky_number, 0),
+    PB_FIELD(  2, BYTES   , REQUIRED, STATIC  , OTHER, SimpleMessage, name, lucky_number, 0),
+    PB_LAST_FIELD
+};
+
+
diff --git a/examples/nanopb/simple.pb.h b/examples/nanopb/simple.pb.h
new file mode 100644
index 0000000000..47521dee69
--- /dev/null
+++ b/examples/nanopb/simple.pb.h
@@ -0,0 +1,45 @@
+/* Automatically generated nanopb header */
+/* Generated by nanopb-0.3.1 at Tue Mar 10 01:16:15 2015. */
+
+#ifndef PB_SIMPLE_PB_H_INCLUDED
+#define PB_SIMPLE_PB_H_INCLUDED
+#include <pb.h>
+
+#if PB_PROTO_HEADER_VERSION != 30
+#error Regenerate this file with the current version of nanopb generator.
+#endif
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* Enum definitions */
+/* Struct definitions */
+typedef PB_BYTES_ARRAY_T(16) SimpleMessage_name_t;
+
+typedef struct _SimpleMessage {
+    int32_t lucky_number;
+    SimpleMessage_name_t name;
+} SimpleMessage;
+
+/* Default values for struct fields */
+
+/* Initializer values for message structs */
+#define SimpleMessage_init_default               {0, {0, {0}}}
+#define SimpleMessage_init_zero                  {0, {0, {0}}}
+
+/* Field tags (for use in manual encoding/decoding) */
+#define SimpleMessage_lucky_number_tag           1
+#define SimpleMessage_name_tag                   2
+
+/* Struct field encoding specification for nanopb */
+extern const pb_field_t SimpleMessage_fields[3];
+
+/* Maximum encoded size of messages (where known) */
+#define SimpleMessage_size                       29
+
+#ifdef __cplusplus
+} /* extern "C" */
+#endif
+
+#endif
diff --git a/examples/nanopb/simple.proto b/examples/nanopb/simple.proto
new file mode 100644
index 0000000000..1905d0e50b
--- /dev/null
+++ b/examples/nanopb/simple.proto
@@ -0,0 +1,10 @@
+// A very simple protocol definition, consisting of only
+// one message.
+
+message SimpleMessage {
+    required int32 lucky_number = 1;
+	required bytes name = 2;
+}
+
+
+