feat: IEC 61850 protocol module

.gitmodules

@@ -13,3 +13,9 @@
 [submodule "src/c++/deps/opendnp3"]
 	path = src/c++/deps/opendnp3
 	url = https://github.com/dnp3/opendnp3.git
+[submodule "src/c/deps/json-c"]
+	path = src/c/deps/json-c
+	url = https://github.com/json-c/json-c.git
+[submodule "src/c/deps/libiec61850"]
+	path = src/c/deps/libiec61850
+	url = https://github.com/mz-automation/libiec61850.git

Dockerfile

@@ -44,6 +44,10 @@ ADD CMakeLists.txt /usr/local/src/ot-sim/CMakeLists.txt
 ADD src/c          /usr/local/src/ot-sim/src/c
 ADD src/c++        /usr/local/src/ot-sim/src/c++
 RUN cmake -S /usr/local/src/ot-sim -B /usr/local/src/ot-sim/build \
+  && cmake -S /usr/local/src/ot-sim/src/c/deps/json-c -B /usr/local/src/ot-sim/src/c/deps/json-c/build \
+  && cmake --build /usr/local/src/ot-sim/src/c/deps/json-c/build -j $(nproc) --target install
+  && cmake -S /usr/local/src/ot-sim/src/c/deps/libiec61850 -B /usr/local/src/ot-sim/src/c/deps/libiec61850/build \
+  && cmake --build /usr/local/src/ot-sim/src/c/deps/libiec61850/build -j $(nproc) --target install
   && cmake --build /usr/local/src/ot-sim/build -j $(nproc) --target install
 
 FROM debian:bookworm AS prod

src/c/CMakeLists.txt

@@ -1 +1,8 @@
+set(JSON_INCLUDE_DIRS
+  ${CMAKE_SOURCE_DIR}/deps
+)
+
+add_subdirectory(deps/json-c)
+
+add_subdirectory(cmd/ot-sim-61850-module)
 add_subdirectory(cmd/ot-sim-message-bus)

src/c/cmd/ot-sim-61850-module/CMakeLists.txt

@@ -0,0 +1,22 @@
+find_package(LibXml2 REQUIRED)
+
+include_directories(
+  ${JSON_INCLUDE_DIRS}
+  ${LIBXML2_INCLUDE_DIR}
+)
+
+add_executable(ot-sim-61850-module
+  main.c
+)
+
+target_link_libraries(ot-sim-61850-module
+  czmq
+  ${LIBXML2_LIBRARIES}
+  json-c
+  pthread
+  zmq
+)
+
+install(TARGETS ot-sim-61850-module
+  RUNTIME DESTINATION bin
+)