MicrOBU/obu-firmware/CMakeLists.txt

cmake_minimum_required(VERSION 3.22)
# obu-firmware: the ESP32-C5 half of the MicrOBU station, on the vanetza-idf C-ITS stack.
#
# Since 2026-09-23 this is a port of the colleague's standalone VRU station
# (microbu-esp32c5/firmware, its own git repository beside this one and gitignored here). From it:
# BTP/GeoNetworking and the TS 103 097 security entity (vanetza-idf), the station-link message
# layer over native USB Serial/JTAG and BLE GATT, the NVS credential store, and the C5 radio adapter.
# Added here for this project: the raw receive path of the previous firmware (gn_unwrap.c, forwarded
# as link opcode V2X_RX) so unsigned and non-demo-signed traffic still reaches the phone, the
# unsigned transmit path of the previous firmware (geonet.c), and BLE pausing while USB is in use.
# See NOTES.md.
#
# ESP-IDF 6.0.2 exactly: the C5 radio's private Wi-Fi driver ABI (otm_tx_custom.c) is pinned to it
# by vanetza-idf's radio_c5.cmake and has only been validated there. The previous C firmware was
# built with IDF 6.1; see FLASHING.md for the export script of each.
#
# vanetza-idf is taken from the colleague's tree rather than vendored (it is ~90 MB). Override with
# -DVANETZA_IDF_DIR=... if it lives elsewhere.
if(NOT VANETZA_IDF_DIR)
    set(VANETZA_IDF_DIR "${CMAKE_CURRENT_LIST_DIR}/../microbu-esp32c5/external/vanetza-idf")
endif()
if(NOT EXISTS "${VANETZA_IDF_DIR}/idf_component.yml")
    message(FATAL_ERROR "vanetza-idf not found at ${VANETZA_IDF_DIR}: clone microbu-esp32c5 beside this "
                        "repository or pass -DVANETZA_IDF_DIR=<path to external/vanetza-idf>")
endif()

# Provenance guard for main/otm_tx_custom.c, copied unchanged from microbu-esp32c5/firmware/CMakeLists.txt:
# this checked-in copy is what microbu::C5Radio::request() links against for every transmission.
# Fail configure if either the pinned upstream or this file drifts from the reviewed revision.
set(_otm_upstream "${VANETZA_IDF_DIR}/ports/esp_idf/third_party/otm/main/tx_custom.c")
if(EXISTS "${_otm_upstream}")
    file(READ "${_otm_upstream}" _otm_upstream_text)
    string(REPLACE "\r\n" "\n" _otm_upstream_text "${_otm_upstream_text}")
    string(SHA256 _otm_upstream_hash "${_otm_upstream_text}")
    if(NOT _otm_upstream_hash STREQUAL "cb1dccfef96912ca59275e8a9102f41f56925b94a19d4a4629082aaeb779be1b")
        message(FATAL_ERROR "OpenTrafficMap upstream tx_custom.c differs from the reviewed source revision (674e3412) -- review before updating main/otm_tx_custom.c and this hash")
    endif()
endif()
set(_otm_checked_in "${CMAKE_CURRENT_LIST_DIR}/main/otm_tx_custom.c")
file(READ "${_otm_checked_in}" _otm_checked_in_text)
string(REPLACE "\r\n" "\n" _otm_checked_in_text "${_otm_checked_in_text}")
string(SHA256 _otm_checked_in_hash "${_otm_checked_in_text}")
if(NOT _otm_checked_in_hash STREQUAL "114693af99ce3866cfc767066d484e45822eaf15335d94a03626b60ac5777277")
    message(FATAL_ERROR "main/otm_tx_custom.c differs from the reviewed copy -- review the change, then update this hash")
endif()

list(APPEND EXTRA_COMPONENT_DIRS "${VANETZA_IDF_DIR}")
set(SDKCONFIG_DEFAULTS "${CMAKE_CURRENT_LIST_DIR}/sdkconfig.defaults")
set(COMPONENTS main)
include($ENV{IDF_PATH}/tools/cmake/project.cmake)
project(obu_firmware)
add_compile_options(-Wno-error -Wno-cpp -Wno-error=implicit-function-declaration)
idf_component_get_property(vanetza_lib vanetza-idf COMPONENT_LIB)
if(vanetza_lib)
    target_compile_options(${vanetza_lib} PRIVATE -Wno-error=implicit-function-declaration -Wno-error=cpp)
endif()
# GCC 15's stricter -Warray-bounds false-positives on NimBLE's fixed-size bond-store arrays
# (upstream Apache Mynewt code); demote to a warning so the component still builds.
idf_component_get_property(bt_lib bt COMPONENT_LIB)
if(bt_lib)
    target_compile_options(${bt_lib} PRIVATE -Wno-error=array-bounds)
endif()