# Task 4 Report

status: DONE_WITH_CONCERNS

## Files created/modified

- CMakeLists.txt
- include/mag160c/mag160c.h
- src/core/device.hpp
- src/core/device.cpp
- src/c_api.cpp
- tests/cpp/test_c_api.cpp
- tests/cpp/test_device_model.cpp
- progress.md

## Commands run

```powershell
g++ -std=c++17 -DMAG160C_STATIC -DMAG160C_HAS_LIBUSB=0 -Iinclude -Isrc src\core\error.cpp src\core\context.cpp src\core\tcm_frame.cpp src\core\tcm_device.cpp src\core\device.cpp src\c_api.cpp tests\cpp\test_c_api.cpp -o build_task4_c_api_test.exe
.\build_task4_c_api_test.exe
g++ -std=c++17 -DMAG160C_STATIC -DMAG160C_HAS_LIBUSB=0 -Iinclude -Isrc src\core\error.cpp src\core\context.cpp src\core\tcm_frame.cpp src\core\tcm_device.cpp src\core\device.cpp src\c_api.cpp tests\cpp\test_device_model.cpp -o build_task4_device_model_test.exe
.\build_task4_device_model_test.exe
```

## Test results

- Direct MinGW C++17 compile/run verification passed for test_c_api.
- Direct MinGW C++17 compile/run verification passed for test_device_model.

## Concerns

- CMake/CTest verification remains unavailable because cmake is not installed or not on PATH.
- libusb-enabled enumeration path is implemented under conditional compilation but not compiled in this environment because MAG160C_HAS_LIBUSB=0.
- Generated local executables build_task4_c_api_test.exe and build_task4_device_model_test.exe exist from substitute verification.

## Self-review notes

- Endpoint pair selection returns first bulk IN and first bulk OUT.
- No-libusb list_devices path returns MAG160C_ERR_UNSUPPORTED and clears output pointers/count through the C ABI.
- C ABI device list allocation uses new[] and free uses delete[].
- Public device info struct uses only C-compatible fields.

## Fix report: libusb-enabled list_devices test compatibility

status: DONE

### Files modified

- CMakeLists.txt
- tests/cpp/test_c_api.cpp

### Commands run

```powershell
g++ -std=c++17 -DMAG160C_STATIC -DMAG160C_HAS_LIBUSB=0 -Iinclude -Isrc src\core\error.cpp src\core\context.cpp src\core\tcm_frame.cpp src\core\tcm_device.cpp src\core\device.cpp src\c_api.cpp tests\cpp\test_c_api.cpp -o build_task4_c_api_test.exe
.\build_task4_c_api_test.exe
g++ -std=c++17 -DMAG160C_STATIC -DMAG160C_HAS_LIBUSB=0 -Iinclude -Isrc src\core\error.cpp src\core\context.cpp src\core\tcm_frame.cpp src\core\tcm_device.cpp src\core\device.cpp src\c_api.cpp tests\cpp\test_device_model.cpp -o build_task4_device_model_test.exe
.\build_task4_device_model_test.exe
```

### Test results

- Direct MinGW C++17 compile/run verification passed for test_c_api.
- Direct MinGW C++17 compile/run verification passed for test_device_model.

### Self-review

- test_c_api now expects MAG160C_ERR_UNSUPPORTED only when MAG160C_HAS_LIBUSB is 0.
- test_c_api accepts MAG160C_OK and frees any returned device list when MAG160C_HAS_LIBUSB is 1.
- CMake now propagates MAG160C_HAS_LIBUSB to test_c_api via MAG160C_HAS_LIBUSB_VALUE.