# If Arduino component is available, use C++ main and link Arduino. # The component name matches the directory basename of ARDUINO_ESP32_PATH # (e.g. "arduino-esp32" when cloned from GitHub). if(DEFINED ENV{ARDUINO_ESP32_PATH}) get_filename_component(_arduino_comp_name $ENV{ARDUINO_ESP32_PATH} NAME) # arduino-esp32 ships esp32-camera as a precompiled static lib but does # NOT export its headers from its main CMakeLists. Sketches that # #include "esp_camera.h" therefore fail to compile under the IDF # build path. We add the bundled headers to the main component's # INCLUDE_DIRS unconditionally — harmless for non-camera sketches and # the only reliable path for camera sketches under our QEMU pipeline. # Normalize Windows backslashes → forward slashes; otherwise CMake # parses the resulting paths as escape sequences (\E, \U etc). file(TO_CMAKE_PATH "$ENV{ARDUINO_ESP32_PATH}" _arduino_path_norm) set(_cam_root "${_arduino_path_norm}/tools/sdk/${IDF_TARGET}/include/esp32-camera") set(_cam_includes "") if(EXISTS "${_cam_root}/driver/include") list(APPEND _cam_includes "${_cam_root}/driver/include") endif() if(EXISTS "${_cam_root}/conversions/include") list(APPEND _cam_includes "${_cam_root}/conversions/include") endif() # Glob every .cpp / .c that the espidf_compiler dropped into main/ # alongside main.cpp. Multi-file Arduino projects (robot-desktop-eyes, # any wokwi.zip with helper .cpp files, etc.) define classes/free # functions in their own translation units; if SRCS only names # "main.cpp" the linker dies with "undefined reference to Foo::bar()" # for every symbol that lives in a helper .cpp. # # No CONFIGURE_DEPENDS — ESP-IDF's component_get_requirements.cmake # evaluates each component's CMakeLists in script mode where # CONFIGURE_DEPENDS isn't supported, and the build aborts with # "CONFIGURE_DEPENDS is invalid for script and find package modes". # We don't need it anyway: espidf_compiler wipes + restores main/ # from the template on every compile (touching CMakeLists.txt's # mtime), so cmake re-globs naturally on the next configure run. file(GLOB _user_srcs "${CMAKE_CURRENT_LIST_DIR}/*.cpp" "${CMAKE_CURRENT_LIST_DIR}/*.c") idf_component_register( SRCS ${_user_srcs} INCLUDE_DIRS "." ${_cam_includes} # `driver` brings in the i2c_master_* + i2c_cmd_link_* symbols # libesp32-camera.a's sccb.c references at link time. arduino-esp32 # doesn't transitively expose it, so we name it here. REQUIRES ${_arduino_comp_name} driver ) # Link the precompiled libesp32-camera.a so esp_camera_init / fb_get # symbols resolve at link time. The .a ships under the same arduino-esp32 # tree; if it is missing (older bundle) we silently skip. # Use ESP-IDF's add_prebuilt_library so cmake creates a proper imported # target with REQUIRES for driver (the .a depends on i2c_master_* + # i2c_cmd_link_*) — that way the linker resolves the cross-lib refs. # target_link_libraries with INTERFACE doesn't propagate REQUIRES, which # is why a bare .a link fails with "undefined reference to i2c_master_…". set(_cam_lib "${_arduino_path_norm}/tools/sdk/${IDF_TARGET}/lib/libesp32-camera.a") if(EXISTS "${_cam_lib}") add_prebuilt_library(esp32_camera_prebuilt "${_cam_lib}" REQUIRES driver ${_arduino_comp_name}) target_link_libraries(${COMPONENT_LIB} PUBLIC esp32_camera_prebuilt) endif() # arduino-esp32 v2.x's generic `esp32` variant pins_arduino.h does NOT # define LED_BUILTIN, so the default Arduino Blink sketch (which Velxio # ships in every new project) fails to compile with # error: 'LED_BUILTIN' was not declared in this scope # Provide a fallback so sketches "just compile". GPIO 2 is the # convention on most ESP32 dev boards (DOIT, NodeMCU, Wemos D1 R32); # for ESP32-CAM where GPIO 2 isn't broken out, the user should use an # explicit pin number — but this default keeps the new-project flow # smooth. # # SKIP on ESP32-C3 and S3 variants: their pins_arduino.h DOES define # LED_BUILTIN already (as `static const uint8_t LED_BUILTIN = ...;` # plus `#define LED_BUILTIN LED_BUILTIN`). Pre-defining it from the # command line clashes with the self-define: the preprocessor expands # `static const uint8_t LED_BUILTIN = ...` to `static const uint8_t 2 = ...` # which is a syntax error. Only set the fallback for the generic ESP32 # Xtensa variant that genuinely lacks the symbol. if(NOT IDF_TARGET STREQUAL "esp32c3" AND NOT IDF_TARGET STREQUAL "esp32s3") target_compile_definitions(${COMPONENT_LIB} PRIVATE "LED_BUILTIN=2") endif() # Relax `-Werror=` for user sketches. ESP-IDF defaults treat several # warning categories as errors (-Werror=comment, -Werror=missing-field- # initializers, etc.) which is great for IDF itself but ruthless for # user Arduino code that often has nested /* */ comments, # parenthesized macros, or other idioms that compile fine under # arduino-cli's permissive defaults. Demoting these to plain warnings # gives users the same "it just compiles" experience they expect from # the Arduino IDE without disabling -Wall entirely. target_compile_options(${COMPONENT_LIB} PRIVATE -Wno-error=comment -Wno-error=parentheses -Wno-error=sign-compare -Wno-error=narrowing -Wno-error=write-strings -Wno-error=missing-field-initializers -Wno-error=reorder) else() # Pure ESP-IDF mode: main.c #includes sketch_translated.c idf_component_register( SRCS "main.c" INCLUDE_DIRS "." ) endif()