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-rw-r--r--examples/simple/Makefile21
-rw-r--r--examples/simple/README.txt29
-rw-r--r--examples/simple/simple.c68
-rw-r--r--examples/simple/simple.proto7
4 files changed, 125 insertions, 0 deletions
diff --git a/examples/simple/Makefile b/examples/simple/Makefile
new file mode 100644
index 0000000..02a4c3f
--- /dev/null
+++ b/examples/simple/Makefile
@@ -0,0 +1,21 @@
+# Include the nanopb provided Makefile rules
+include ../../extra/nanopb.mk
+
+# Compiler flags to enable all warnings & debug info
+CFLAGS = -Wall -Werror -g -O0
+CFLAGS += -I$(NANOPB_DIR)
+
+# C source code files that are required
+CSRC = simple.c # The main program
+CSRC += simple.pb.c # The compiled protocol definition
+CSRC += $(NANOPB_DIR)/pb_encode.c # The nanopb encoder
+CSRC += $(NANOPB_DIR)/pb_decode.c # The nanopb decoder
+
+# Build rule for the main program
+simple: $(CSRC)
+ $(CC) $(CFLAGS) -osimple $(CSRC)
+
+# Build rule for the protocol
+simple.pb.c: simple.proto
+ $(PROTOC) $(PROTOC_OPTS) --nanopb_out=. simple.proto
+
diff --git a/examples/simple/README.txt b/examples/simple/README.txt
new file mode 100644
index 0000000..ee77bfc
--- /dev/null
+++ b/examples/simple/README.txt
@@ -0,0 +1,29 @@
+Nanopb example "simple"
+=======================
+
+This example demonstrates the very basic use of nanopb. It encodes and
+decodes a simple message.
+
+The code uses four different API functions:
+
+ * pb_ostream_from_buffer() to declare the output buffer that is to be used
+ * pb_encode() to encode a message
+ * pb_istream_from_buffer() to declare the input buffer that is to be used
+ * pb_decode() to decode a message
+
+Example usage
+-------------
+
+On Linux, simply type "make" to build the example. After that, you can
+run it with the command: ./simple
+
+On other platforms, you first have to compile the protocol definition using
+the following command::
+
+ ../../generator-bin/protoc --nanopb_out=. simple.proto
+
+After that, add the following four files to your project and compile:
+
+ simple.c simple.pb.c pb_encode.c pb_decode.c
+
+
diff --git a/examples/simple/simple.c b/examples/simple/simple.c
new file mode 100644
index 0000000..3127230
--- /dev/null
+++ b/examples/simple/simple.c
@@ -0,0 +1,68 @@
+#include <stdio.h>
+#include <pb_encode.h>
+#include <pb_decode.h>
+#include "simple.pb.h"
+
+int main()
+{
+ /* 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;
+
+ /* 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)
+ {
+ printf("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)
+ {
+ printf("Decoding failed: %s\n", PB_GET_ERROR(&stream));
+ return 1;
+ }
+
+ /* Print the data contained in the message. */
+ printf("Your lucky number was %d!\n", message.lucky_number);
+ }
+
+ return 0;
+}
+
diff --git a/examples/simple/simple.proto b/examples/simple/simple.proto
new file mode 100644
index 0000000..26e72f4
--- /dev/null
+++ b/examples/simple/simple.proto
@@ -0,0 +1,7 @@
+// A very simple protocol definition, consisting of only
+// one message.
+
+message SimpleMessage {
+ required int32 lucky_number = 1;
+}
+