Fix ignored device settings type override

src/methods.cpp

@@ -2200,6 +2200,11 @@ PyObject* meth_get_device_settings(PyObject* self, PyObject* args)
     if (!PyArg_ParseTuple(args, arg_parse("O|lI:", __FUNCTION__), &obj, &device_type_override, &vnet_slot_arg)) {
         return NULL;
     }
+    if (device_type_override != -1 &&
+        (device_type_override < 0 || device_type_override >= DeviceSettingsTypeMax)) {
+        PyErr_SetString(PyExc_ValueError, "device_type must be -1 or a valid EDeviceSettingsType");
+        return NULL;
+    }
     EPlasmaIonVnetChannel_t vnet_slot = static_cast<EPlasmaIonVnetChannel_t>(vnet_slot_arg);
 
     // Before we do anything, we need to grab the python s_device_settings ctype.Structure.
@@ -2243,6 +2248,8 @@ PyObject* meth_get_device_settings(PyObject* self, PyObject* args)
                 Py_DECREF(settings);
                 return set_ics_exception(exception_runtime_error(), "icsneoGetDeviceSettingsType() Failed");
             }
+        } else {
+            *setting_type = static_cast<EDeviceSettingsType>(device_type_override);
         }
         // int _stdcall icsneoGetDeviceSettings(void* hObject, SDeviceSettings* pSettings, int iNumBytes,
         // EPlasmaIonVnetChannel_t vnetSlot)

tests/test_device_settings.py

@@ -0,0 +1,133 @@
+"""Hardware-free checks of the settings type passed across the native ABI."""
+
+import os
+from pathlib import Path
+import shutil
+import subprocess
+import sys
+
+import pytest
+
+
+@pytest.fixture(scope="module")
+def settings_library(tmp_path_factory):
+    directory = tmp_path_factory.mktemp("settings-library")
+    source = directory / "settings.c"
+    source.write_text(r"""
+#ifdef _WIN32
+#define API __declspec(dllexport)
+#define CALL __stdcall
+#else
+#define API
+#define CALL
+#endif
+static int received = -99, discoveries, requests, slot, size;
+API int CALL icsneoGetDeviceSettingsType(void* handle, int vnet, int* type) {
+    ++discoveries;
+    slot = vnet;
+    *type = 27;
+    return vnet != 98;
+}
+API int CALL icsneoGetDeviceSettings(void* handle, int* settings, int bytes, int vnet) {
+    ++requests;
+    received = *settings;
+    slot = vnet;
+    size = bytes;
+    return vnet != 99;
+}
+API int observed(int field) {
+    switch (field) {
+    case 0: return received;
+    case 1: return discoveries;
+    case 2: return requests;
+    case 3: return slot;
+    default: return size;
+    }
+}
+""")
+    if sys.platform == "win32":
+        compiler = shutil.which("clang-cl")
+        linker = shutil.which("lld-link")
+        if not compiler or not linker:
+            pytest.skip("LLVM clang-cl and lld-link are required for the mock DLL")
+        library = directory / "settings.dll"
+        obj = directory / "settings.obj"
+        target = "i686" if sys.maxsize <= 2**32 else "x86_64"
+        subprocess.run([compiler, f"--target={target}-pc-windows-msvc", "/nologo", "/c", "/GS-", "/Zl",
+                        str(source), f"/Fo{obj}"], check=True, capture_output=True, timeout=60)
+        # The wrapper resolves undecorated API names, also on 32-bit Windows.
+        exports = [] if target == "x86_64" else [
+            "/export:icsneoGetDeviceSettings=_icsneoGetDeviceSettings@16",
+            "/export:icsneoGetDeviceSettingsType=_icsneoGetDeviceSettingsType@12",
+        ]
+        subprocess.run([linker, "/dll", "/noentry", "/nodefaultlib", f"/out:{library}", str(obj), *exports],
+                       check=True, capture_output=True, timeout=60)
+    else:
+        compiler = shutil.which("cc")
+        if not compiler:
+            pytest.skip("A C compiler is required for the mock library")
+        library = directory / ("settings.dylib" if sys.platform == "darwin" else "settings.so")
+        subprocess.run([compiler, "-dynamiclib" if sys.platform == "darwin" else "-shared", "-fPIC",
+                        str(source), "-o", str(library)], check=True, capture_output=True, timeout=60)
+    return library
+
+
+@pytest.mark.parametrize("scenario", ["override", "first", "last", "discovery", "sentinel",
+                                     "invalid", "overflow", "discovery_failure", "settings_failure"])
+def test_device_settings_type(settings_library, scenario):
+    # Isolate the process-global library override from all other tests.
+    script = r"""
+import ctypes
+import sys
+import ics
+
+library, scenario = sys.argv[1:]
+ics.override_library_name(library)
+mock = ctypes.CDLL(library)
+mock.observed.argtypes = [ctypes.c_int]
+mock.observed.restype = ctypes.c_int
+device = ics.PyNeoDeviceEx()
+device._auto_handle_close = False
+if scenario in ('invalid', 'overflow'):
+    values = (-2, ics.DeviceSettingsTypeMax, ics.DeviceSettingsTypeMax + 1, 0xFFFFFFFF)
+    if scenario == 'overflow':
+        values = (2**100, -(2**100))
+    for value in values:
+        try:
+            ics.get_device_settings(device, value)
+        except (ValueError, OverflowError):
+            pass
+        else:
+            raise AssertionError(f'accepted invalid override {value}')
+    assert mock.observed(1) == mock.observed(2) == 0
+elif scenario in ('discovery_failure', 'settings_failure'):
+    discovery = scenario == 'discovery_failure'
+    name = 'icsneoGetDeviceSettingsType()' if discovery else 'icsneoGetDeviceSettings()'
+    try:
+        ics.get_device_settings(device, -1 if discovery else ics.DeviceFire3SettingsType,
+                                98 if discovery else 99)
+    except ics.RuntimeError as error:
+        assert name in str(error)
+    else:
+        raise AssertionError('native failure was ignored')
+    assert mock.observed(1) == int(discovery)
+    assert mock.observed(2) == int(not discovery)
+else:
+    expected = {'override': ics.DeviceFire3SettingsType, 'first': 0,
+                'last': ics.DeviceSettingsTypeMax - 1}.get(scenario, ics.DeviceRADJupiterSettingsType)
+    if scenario == 'discovery':
+        result = ics.get_device_settings(device)
+    else:
+        result = ics.get_device_settings(device, -1 if scenario == 'sentinel' else expected, 2)
+    assert mock.observed(0) == expected
+    assert result.DeviceSettingType == expected
+    assert mock.observed(1) == int(scenario in ('discovery', 'sentinel'))
+    assert mock.observed(2) == 1
+    assert mock.observed(3) == (ics.PlasmaIonVnetChannelMain if scenario == 'discovery' else 2)
+    assert mock.observed(4) == ctypes.sizeof(result)
+"""
+    env = os.environ.copy()
+    env["PYTHONPATH"] = os.pathsep.join(str(Path(path).resolve()) for path in sys.path)
+    result = subprocess.run([sys.executable, "-c", script, str(settings_library), scenario],
+                            env=env, capture_output=True, text=True, timeout=30)
+    assert result.returncode == 0, result.stdout + result.stderr