def test_array_from_ptr(self):
# cfixed_dim arrmeta is redundant so this is ok
a = (ctypes.c_int32 * 3)()
a[0] = 3
a[1] = 6
a[2] = 9
# Readwrite version using cfixed
b = _lowlevel.array_from_ptr('cfixed[3] * int32',
ctypes.addressof(a), a, 'readwrite')
self.assertEqual(_lowlevel.data_address_of(b), ctypes.addressof(a))
self.assertEqual(nd.dshape_of(b), '3 * int32')
self.assertEqual(nd.as_py(b), [3, 6, 9])
b[1] = 10
self.assertEqual(a[1], 10)
# Readonly version using cfixed
b = _lowlevel.array_from_ptr('cfixed[3] * int32',
ctypes.addressof(a), a, 'readonly')
self.assertEqual(nd.as_py(b), [3, 10, 9])
def assign_to(b):
b[1] = 100
self.assertRaises(RuntimeError, assign_to, b)
# Using a fixed dim default-constructs the arrmeta, so works too
b = _lowlevel.array_from_ptr('3 * int32', ctypes.addressof(a),
a, 'readonly')
self.assertEqual(nd.as_py(b), [3, 10, 9])
# Should get an error if we try strided, because the size is unknown
self.assertRaises(RuntimeError,
lambda: _lowlevel.array_from_ptr('strided * int32',
ctypes.addressof(a),
a, 'readonly'))
def data_descriptor_from_cffi(ffi, cdata, writable):
"""
Parameters
----------
ffi : cffi.FFI
The cffi namespace which contains the cdata.
cdata : cffi.CData
The cffi data object which owns the data.
writable : bool
Should be true if the data is writable, flase
if it's read-only.
"""
if not isinstance(cdata, ffi.CData):
raise TypeError('object is not a cffi.CData object, has type %s' %
type(cdata))
owner = (ffi, cdata)
# Get the raw pointer out of the cdata as an integer
ptr = int(ffi.cast('uintptr_t', ffi.cast('char *', cdata)))
ds = datashape.from_cffi(ffi, ffi.typeof(cdata))
if (isinstance(ds, datashape.DataShape) and
isinstance(ds[0], datashape.TypeVar)):
# If the outermost dimension is an array without fixed
# size, get its size from the data
ds = datashape.DataShape((datashape.Fixed(len(cdata)),) + ds[1:])
access = "readwrite" if writable else "readonly"
dyndarr = _lowlevel.array_from_ptr(ndt.type(str(ds)),
ptr, owner, access)
return DyNDDataDescriptor(dyndarr)
def data_descriptor_from_cffi(ffi, cdata, writable):
"""
Parameters
----------
ffi : cffi.FFI
The cffi namespace which contains the cdata.
cdata : cffi.CData
The cffi data object which owns the data.
writable : bool
Should be true if the data is writable, flase
if it's read-only.
"""
if not isinstance(cdata, ffi.CData):
raise TypeError('object is not a cffi.CData object, has type %s' %
type(cdata))
owner = (ffi, cdata)
# Get the raw pointer out of the cdata as an integer
ptr = int(ffi.cast('uintptr_t', ffi.cast('char *', cdata)))
ds = datashape.from_cffi(ffi, ffi.typeof(cdata))
if (isinstance(ds, datashape.DataShape)
and isinstance(ds[0], datashape.TypeVar)):
# If the outermost dimension is an array without fixed
# size, get its size from the data
ds = datashape.DataShape(*(datashape.Fixed(len(cdata)), ) + ds[1:])
access = "readwrite" if writable else "readonly"
dyndarr = _lowlevel.array_from_ptr(ndt.type(str(ds)), ptr, owner, access)
return DyNDDataDescriptor(dyndarr)
def test_array_from_ptr(self):
a = (ctypes.c_int32 * 3)()
a[0] = 3
a[1] = 6
a[2] = 9
# Readwrite version
b = _lowlevel.array_from_ptr(ndt.type('3 * int32'), ctypes.addressof(a),
a, 'readwrite')
self.assertEqual(_lowlevel.data_address_of(b), ctypes.addressof(a))
self.assertEqual(nd.dshape_of(b), '3 * int32')
self.assertEqual(nd.as_py(b), [3, 6, 9])
b[1] = 10
self.assertEqual(a[1], 10)
# Readonly version
b = _lowlevel.array_from_ptr(ndt.type('3 * int32'), ctypes.addressof(a),
a, 'readonly')
self.assertEqual(nd.as_py(b), [3, 10, 9])
def assign_to(b):
b[1] = 100
self.assertRaises(RuntimeError, assign_to, b)
def test_array_from_ptr_struct(self):
class SomeStruct(ctypes.Structure):
_fields_ = [('x', ctypes.c_int8),
('y', ctypes.c_int32),
('z', ctypes.c_double)]
a = SomeStruct()
a.x = 1
a.y = 2
a.z = 3.75
b = _lowlevel.array_from_ptr('{x: int8, y: int32, z: float64}',
ctypes.addressof(a), a, 'readonly')
self.assertEqual(nd.as_py(b, tuple=True), (1, 2, 3.75))
def write_single(self, idx, ptr):
if len(idx) != self.nindex:
raise IndexError('Incorrect number of indices (got %d, require %d)' %
(len(idx), self.nindex))
idx = tuple(operator.index(i) for i in idx)
# Create a temporary DyND array around the ptr data.
# Note that we can't provide an owner because the parameter
# is just the bare pointer.
tmp = _lowlevel.array_from_ptr(self._c_dtype, ptr,
None, 'readonly')
# Use DyND's assignment to set the values
self._dyndarr[idx] = tmp
def data_descriptor_from_ctypes(cdata, writable):
"""
Parameters
----------
cdata : ctypes data instance
The ctypes data object which owns the data.
writable : bool
Should be true if the data is writable, flase
if it's read-only.
"""
ds = datashape.from_ctypes(type(cdata))
access = "readwrite" if writable else "readonly"
dyndarr = _lowlevel.array_from_ptr(ndt.type(str(ds)),
ctypes.addressof(cdata), cdata, access)
return DyNDDataDescriptor(dyndarr)
def data_descriptor_from_ctypes(cdata, writable):
"""
Parameters
----------
cdata : ctypes data instance
The ctypes data object which owns the data.
writable : bool
Should be true if the data is writable, flase
if it's read-only.
"""
ds = datashape.from_ctypes(type(cdata))
access = "readwrite" if writable else "readonly"
dyndtp = " * ".join(["cfixed[%d]" % int(x) for x in ds[:-1]] + [str(ds[-1])])
dyndarr = _lowlevel.array_from_ptr(ndt.type(dyndtp), ctypes.addressof(cdata), cdata, access)
return DyND_DDesc(dyndarr)
def data_descriptor_from_ctypes(cdata, writable):
"""
Parameters
----------
cdata : ctypes data instance
The ctypes data object which owns the data.
writable : bool
Should be true if the data is writable, flase
if it's read-only.
"""
ds = datashape.from_ctypes(type(cdata))
access = "readwrite" if writable else "readonly"
dyndarr = _lowlevel.array_from_ptr(ndt.type(str(ds)),
ctypes.addressof(cdata), cdata,
access)
return DyNDDataDescriptor(dyndarr)
def data_descriptor_from_ctypes(cdata, writable):
"""
Parameters
----------
cdata : ctypes data instance
The ctypes data object which owns the data.
writable : bool
Should be true if the data is writable, flase
if it's read-only.
"""
ds = datashape.from_ctypes(type(cdata))
access = "readwrite" if writable else "readonly"
dyndtp = ' * '.join(['cfixed[%d]' % int(x)
for x in ds[:-1]] + [str(ds[-1])])
dyndarr = _lowlevel.array_from_ptr(ndt.type(dyndtp),
ctypes.addressof(cdata), cdata, access)
return DyND_DDesc(dyndarr)
def test_array_from_ptr_blockref(self):
a = ctypes.pointer(ctypes.c_double(1.25))
b = _lowlevel.array_from_ptr('pointer[float64]',
ctypes.addressof(a), a, 'readonly')
self.assertEqual(nd.as_py(b), 1.25)
