TCP/IP Bundle Unix (#34)

* first sketch of tcp/ip bundle on unix

* fixed bug in bundle and added errors

* factoring out encoding and decoding of protobuf

* working state with extra function to toggle blocking vs non-blocking

* code cleanup

* adding nanopb as a proper git submodule

* exclude protobuf generated files from checks

* fixing ci

Author: tanneberger

.clang-tidy

@@ -9,8 +9,10 @@ Checks: '
     cert-*,
     -readability-else-after-return,
     -clang-analyzer-core.CallAndMessage,
-    -clang-analyzer-security.insecureAPI.DeprecatedOrUnsafeBufferHandling'
+    -clang-analyzer-security.insecureAPI.DeprecatedOrUnsafeBufferHandling
+    -modernize-macro-to-enum
+    '
 WarningsAsErrors: true
 HeaderFilterRegex: ''
 AnalyzeTemporaryDtors: false
-FormatStyle: none
+FormatStyle: none

.gitmodules

@@ -1,3 +1,6 @@
 [submodule "external/Unity"]
 	path = external/Unity
 	url = https://github.com/ThrowTheSwitch/Unity.git
+[submodule "external/nanopb"]
+	path = external/nanopb
+	url = https://github.com/nanopb/nanopb.git

CMakeLists.txt

@@ -2,6 +2,7 @@ cmake_minimum_required(VERSION 3.9)
 project(reactor-uc LANGUAGES C)
 
 # Command line options for the build
+set(BUILD_EXAMPLES ON CACHE BOOL "Build examples")
 set(BUILD_TESTS OFF CACHE BOOL "Build all tests")
 set(BUILD_LF_TESTS OFF CACHE BOOL "Build lf tests")
 set(BUILD_UNIT_TESTS OFF CACHE BOOL "Build unit tests")
@@ -38,19 +39,39 @@ if(BUILD_TESTS)
   endif()
 endif()
 
-# TODO: Explicitly name all the sources.
-file(GLOB SOURCES "src/*.c")
-message(${SOURCES})
+file(GLOB SOURCES "src/*.c" "src/generated/*.c")
+
+# you maybe think this is stupid, but the nanopb cmake-package exports only cpp functions & libraries
+add_library(nanopb
+        external/nanopb/pb_decode.c
+        external/nanopb/pb_encode.c
+        external/nanopb/pb_decode.c
+        external/nanopb/pb_common.c
+)
+
+set_target_properties(nanopb PROPERTIES C_CLANG_TIDY "") # Disable clang-tidy for this external lib.
+set_source_files_properties("external/nanopb/*.c" PROPERTIES SKIP_LINTING ON)
+set_source_files_properties(src/generated/message.pb.c include/reactor-uc/generated/message.pb.h PROPERTIES SKIP_LINTING ON)
 
 if (PLATFORM STREQUAL "POSIX")
   add_library(reactor-uc STATIC ${SOURCES})
-  target_compile_definitions(reactor-uc PUBLIC PLATFORM_POSIX)
-  target_link_libraries(reactor-uc PRIVATE pthread)
+  add_compile_definitions(PLATFORM_POSIX)
+  target_include_directories(reactor-uc PUBLIC external/)
+  target_link_libraries(reactor-uc PRIVATE pthread nanopb)
+
+  if(BUILD_EXAMPLES)
+    add_subdirectory(examples/posix)
+  endif ()
+
 elseif (PLATFORM STREQUAL "ZEPHYR")
   zephyr_library_named(reactor-uc)
   zephyr_library_sources(${SOURCES})
   zephyr_library_link_libraries(kernel)
   add_compile_definitions(PLATFORM_ZEPHYR)
+
+  if(BUILD_EXAMPLES)
+    add_subdirectory(examples/zephyr)
+  endif ()
 else ()
   message(FATAL_ERROR "No valid platform specified")
 endif ()

Makefile

@@ -30,19 +30,18 @@ asan:
 	make test -C build
 
 # Format the code base
-SRC_FILES := $(shell find src -name '*.c')
-HDR_FILES := $(shell find include -name '*.h')
+SRC_FILES := $(shell find ./src -path ./src/generated -prune -o -name '*.c' -print)
+HDR_FILES := $(shell find ./include -path ./include/reactor-uc/generated -prune -o -name '*.h' -print)
+
 format:
 	clang-format -i -style=file $(SRC_FILES) $(HDR_FILES)
 
 # Check that the code base is formatted
 format-check:
 	clang-format --dry-run --Werror -style=file $(SRC_FILES) $(HDR_FILES)
 
-
 # Run the entire CI flow
 ci: clean test coverage format-check
 
-
 clean:
 	rm -rf build

examples/CMakeLists.txt

@@ -1,9 +1,14 @@
 cmake_minimum_required(VERSION 3.20.0)
 set(PLATFORM "POSIX" CACHE STRING "Platform to target")
 
-project(timer-ex)
+add_executable(timer_ex timer_ex.c)
+target_link_libraries(timer_ex PRIVATE reactor-uc)
 
-add_executable(timer_ex)
-target_sources(timer_ex PRIVATE timer_ex.c)
-add_subdirectory(../../ reactor-uc)
-target_link_libraries(timer_ex PRIVATE reactor-uc)
+add_executable(tcp_ip_bundle_server testing_posix_tcp_ip_bundle_server.c)
+target_link_libraries(tcp_ip_bundle_server PUBLIC reactor-uc)
+
+add_executable(tcp_ip_bundle_client testing_posix_tcp_ip_bundle_client.c)
+target_link_libraries(tcp_ip_bundle_client PUBLIC reactor-uc)
+
+add_executable(nanopb_test testing_nanopb.c)
+target_link_libraries(nanopb_test PRIVATE reactor-uc nanopb)

examples/posix/CMakeLists.txt

@@ -0,0 +1,38 @@
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "../../../reactor-uc/include/reactor-uc/generated/message.pb.h"
+#include "../../../reactor-uc/include/reactor-uc/encoding.h"
+
+#define BUFFER_SIZE 1024
+#define MSG_ID 42
+
+int main() {
+
+  PortMessage original_message;
+  PortMessage deserialized_message;
+  unsigned char buffer[BUFFER_SIZE];
+  unsigned char * message = NULL;
+  int message_size = 0;
+
+  original_message.connection_number = MSG_ID;
+  const char* text = "Hello World1234";
+  memcpy(original_message.message, text, sizeof("Hello World1234")); // NOLINT
+
+  message = buffer;
+  message_size = encode_protobuf(&original_message, buffer, BUFFER_SIZE);
+  if (message_size < 0) {
+    printf("encoding failed!\n");
+    exit(1);
+  }
+
+  int remaining_bytes = decode_protobuf(&deserialized_message, message, message_size);
+
+  if (remaining_bytes < 0) {
+    printf("decoding failed!\n");
+    exit(1);
+  }
+
+  printf("o: %i d: %i\n", original_message.connection_number, deserialized_message.connection_number);
+  printf("o: %s d: %s\n", original_message.message, deserialized_message.message);
+}

examples/posix/testing_nanopb.c

@@ -0,0 +1,42 @@
+#include "reactor-uc/reactor-uc.h"
+#include "reactor-uc/platform/posix/tcp_ip_bundle.h"
+#include <sys/socket.h>
+#include <unistd.h>
+
+#include "reactor-uc/generated/message.pb.h"
+
+int main() {
+  TcpIpBundle bundle;
+
+  // server address
+  const char* host = "127.0.0.1";
+  unsigned short port = 8900; // NOLINT
+
+  // message for server
+  PortMessage port_message;
+  port_message.connection_number = 42; // NOLINT
+  const char* message = "Hello World1234";
+  memcpy(port_message.message, message, sizeof("Hello World1234")); // NOLINT
+
+  // creating a server that listens on loopback device on port 8900
+  TcpIpBundle_ctor(&bundle, host, port, AF_INET);
+
+  // binding to that address
+  bundle.connect(&bundle);
+
+  // change the bundle to non-blocking
+  bundle.change_block_state(&bundle, false);
+
+  // sending message
+  bundle.send(&bundle, &port_message);
+
+  // waiting for reply
+  PortMessage* received_message = NULL;
+  do {
+    received_message = bundle.receive(&bundle);
+  } while (received_message == NULL);
+
+  printf("Received message with connection number %i and content %s\n", received_message->connection_number, received_message->message);
+
+  bundle.close(&bundle);
+}

examples/posix/testing_posix_tcp_ip_bundle_client.c

@@ -0,0 +1,39 @@
+#include "reactor-uc/reactor-uc.h"
+#include "reactor-uc/platform/posix/tcp_ip_bundle.h"
+#include <sys/socket.h>
+#include <unistd.h>
+
+int main() {
+  TcpIpBundle bundle;
+
+  const char* host = "127.0.0.1";
+  unsigned short port = 8900; // NOLINT
+
+  // creating a server that listens on loopback device on port 8900
+  TcpIpBundle_ctor(&bundle, host, port, AF_INET);
+
+  // binding to that address
+  bundle.bind(&bundle);
+
+  // change the bundle to non-blocking
+  bundle.change_block_state(&bundle, false);
+
+  // accept one connection
+  bool new_connection;
+  do {
+     new_connection = bundle.accept(&bundle);
+  } while (!new_connection);
+
+  // waiting for messages from client
+  PortMessage* message = NULL;
+  do {
+    message = bundle.receive(&bundle);
+    sleep(1);
+  } while (message == NULL);
+
+  printf("Received message with connection number %i and content %s\n", message->connection_number, message->message);
+
+  bundle.send(&bundle, message);
+
+  bundle.close(&bundle);
+}

examples/posix/testing_posix_tcp_ip_bundle_server.c

@@ -0,0 +1,32 @@
+#ifndef REACTOR_UC_ENCODING_H
+#define REACTOR_UC_ENCODING_H
+
+#include "generated/message.pb.h"
+#include <nanopb/pb_decode.h>
+#include <nanopb/pb_encode.h>
+
+int encode_protobuf(const PortMessage *message, unsigned char *buffer, size_t buffer_size) {
+  // turing write buffer into pb_ostream buffer
+  pb_ostream_t stream_out = pb_ostream_from_buffer(buffer, buffer_size);
+
+  // serializing protobuf into buffer
+  if (!pb_encode(&stream_out, PortMessage_fields, message)) {
+    printf("protobuf encoding error %s\n", stream_out.errmsg);
+    return -1;
+  }
+
+  return (int)stream_out.bytes_written;
+}
+
+int decode_protobuf(PortMessage *message, const unsigned char *buffer, size_t buffer_size) {
+  pb_istream_t stream_in = pb_istream_from_buffer(buffer, buffer_size);
+
+  if (!pb_decode(&stream_in, PortMessage_fields, message)) {
+    printf("protobuf decoding error %s\n", stream_in.errmsg);
+    return -1;
+  }
+
+  return (int)stream_in.bytes_left;
+}
+
+#endif // REACTOR_UC_ENCODING_H

external/nanopb

@@ -1,5 +1,6 @@
 #ifndef REACTOR_UC_ERROR_H
 #define REACTOR_UC_ERROR_H
+
 #include <assert.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -14,6 +15,9 @@ typedef enum {
   LF_EMPTY,
   LF_INVALID_VALUE,
   LF_OUT_OF_BOUNDS,
+  LF_INCOMPLETE,
+  LF_COULD_NOT_CONNECT,
+  LF_NETWORK_SETUP_FAILED
 } lf_ret_t;
 
 // Runtime validation. Crashes the program if expr is not true

include/reactor-uc/encoding.h

@@ -0,0 +1,52 @@
+/* Automatically generated nanopb header */
+/* Generated by nanopb-1.0.0-dev */
+
+#ifndef PB_MESSAGE_PB_H_INCLUDED
+#define PB_MESSAGE_PB_H_INCLUDED
+#include <nanopb/pb.h>
+//#include "generator/proto/nanopb.pb.h"
+
+#if PB_PROTO_HEADER_VERSION != 40
+#error Regenerate this file with the current version of nanopb generator.
+#endif
+
+/* Struct definitions */
+typedef struct _PortMessage { // NOLINT
+    int32_t connection_number;
+    char message[833]; // NOLINT
+} PortMessage;
+
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* Initializer values for message structs */
+#define PortMessage_init_default                 {0, ""}
+#define PortMessage_init_zero                    {0, ""}
+
+/* Field tags (for use in manual encoding/decoding) */
+#define PortMessage_connection_number_tag        1
+#define PortMessage_message_tag                  2
+
+/* Struct field encoding specification for nanopb */
+#define PortMessage_FIELDLIST(X, a) \
+X(a, STATIC,   REQUIRED, INT32,    connection_number,   1) \
+X(a, STATIC,   REQUIRED, STRING,   message,           2)
+#define PortMessage_CALLBACK NULL
+#define PortMessage_DEFAULT NULL
+
+extern const pb_msgdesc_t PortMessage_msg;
+
+/* Defines for backwards compatibility with code written before nanopb-0.4.0 */
+#define PortMessage_fields &PortMessage_msg
+
+/* Maximum encoded size of messages (where known) */
+#define MESSAGE_PB_H_MAX_SIZE                    PortMessage_size
+#define PortMessage_size                         846
+
+#ifdef __cplusplus
+} /* extern "C" */
+#endif
+
+#endif

include/reactor-uc/error.h

@@ -0,0 +1,8 @@
+
+import "generator/proto/nanopb.proto";
+
+message PortMessage {
+  required int32 connection_number = 1;
+  required string message = 2 [(nanopb).max_length = 832];
+}
+