diff options
Diffstat (limited to 'libs/nanopb/examples/simple')
-rw-r--r-- | libs/nanopb/examples/simple/Makefile | 22 | ||||
-rw-r--r-- | libs/nanopb/examples/simple/README.txt | 29 | ||||
-rw-r--r-- | libs/nanopb/examples/simple/simple.c | 71 | ||||
-rw-r--r-- | libs/nanopb/examples/simple/simple.proto | 9 |
4 files changed, 131 insertions, 0 deletions
diff --git a/libs/nanopb/examples/simple/Makefile b/libs/nanopb/examples/simple/Makefile new file mode 100644 index 00000000..970a8650 --- /dev/null +++ b/libs/nanopb/examples/simple/Makefile @@ -0,0 +1,22 @@ +# 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 +CSRC += $(NANOPB_DIR)/pb_common.c # The nanopb common parts + +# 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/libs/nanopb/examples/simple/README.txt b/libs/nanopb/examples/simple/README.txt new file mode 100644 index 00000000..ee77bfc7 --- /dev/null +++ b/libs/nanopb/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/libs/nanopb/examples/simple/simple.c b/libs/nanopb/examples/simple/simple.c new file mode 100644 index 00000000..1f6b1373 --- /dev/null +++ b/libs/nanopb/examples/simple/simple.c @@ -0,0 +1,71 @@ +#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! + * 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; + + /* 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 = 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) + { + 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/libs/nanopb/examples/simple/simple.proto b/libs/nanopb/examples/simple/simple.proto new file mode 100644 index 00000000..5c73a3b2 --- /dev/null +++ b/libs/nanopb/examples/simple/simple.proto @@ -0,0 +1,9 @@ +// A very simple protocol definition, consisting of only +// one message. + +syntax = "proto2"; + +message SimpleMessage { + required int32 lucky_number = 1; +} + |