def test_from_ctypes(self):
"""
Test converting a ctypes type to a Numba type.
"""
def check(cty, ty):
got = ctypes_utils.from_ctypes(cty)
self.assertEqual(got, ty)
self._conversion_tests(check)
# An unsupported type
with self.assertRaises(TypeError) as raises:
ctypes_utils.from_ctypes(c_wchar_p)
self.assertIn("Unsupported ctypes type", str(raises.exception))
def carray(ptr, shape, dtype=None):
"""
Return a Numpy array view over the data pointed to by *ptr* with the
given *shape*, in C order. If *dtype* is given, it is used as the
array's dtype, otherwise the array's dtype is inferred from *ptr*'s type.
"""
from numba.core.typing.ctypes_utils import from_ctypes
try:
# Use ctypes parameter protocol if available
ptr = ptr._as_parameter_
except AttributeError:
pass
# Normalize dtype, to accept e.g. "int64" or np.int64
if dtype is not None:
dtype = np.dtype(dtype)
if isinstance(ptr, ctypes.c_void_p):
if dtype is None:
raise TypeError("explicit dtype required for void* argument")
p = ptr
elif isinstance(ptr, ctypes._Pointer):
ptrty = from_ctypes(ptr.__class__)
assert isinstance(ptrty, types.CPointer)
ptr_dtype = as_dtype(ptrty.dtype)
if dtype is not None and dtype != ptr_dtype:
raise TypeError("mismatching dtype '%s' for pointer %s" %
(dtype, ptr))
dtype = ptr_dtype
p = ctypes.cast(ptr, ctypes.c_void_p)
else:
raise TypeError("expected a ctypes pointer, got %r" % (ptr, ))
nbytes = dtype.itemsize * np.product(shape, dtype=np.intp)
return _get_array_from_ptr(p, nbytes, dtype).reshape(shape)
def check(cty, ty):
got = ctypes_utils.from_ctypes(cty)
self.assertEqual(got, ty)