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from _rawffi import alt as _ffi
import _rawffi
from _ctypes.basics import _CData, cdata_from_address, _CDataMeta, sizeof
from _ctypes.basics import keepalive_key, store_reference, ensure_objects
from _ctypes.basics import CArgObject, as_ffi_pointer
class ArrayMeta(_CDataMeta):
def __new__(self, name, cls, typedict):
res = type.__new__(self, name, cls, typedict)
if '_type_' in typedict:
ffiarray = _rawffi.Array(typedict['_type_']._ffishape_)
res._ffiarray = ffiarray
subletter = getattr(typedict['_type_'], '_type_', None)
if subletter == 'c':
def getvalue(self):
return _rawffi.charp2string(self._buffer.buffer,
self._length_)
def setvalue(self, val):
# we don't want to have buffers here
if len(val) > self._length_:
raise ValueError("%r too long" % (val,))
if isinstance(val, str):
_rawffi.rawstring2charp(self._buffer.buffer, val)
else:
for i in range(len(val)):
self[i] = val[i]
if len(val) < self._length_:
self._buffer[len(val)] = '\x00'
res.value = property(getvalue, setvalue)
def getraw(self):
return _rawffi.charp2rawstring(self._buffer.buffer,
self._length_)
def setraw(self, buffer):
if len(buffer) > self._length_:
raise ValueError("%r too long" % (buffer,))
_rawffi.rawstring2charp(self._buffer.buffer, buffer)
res.raw = property(getraw, setraw)
elif subletter == 'u':
def getvalue(self):
return _rawffi.wcharp2unicode(self._buffer.buffer,
self._length_)
def setvalue(self, val):
# we don't want to have buffers here
if len(val) > self._length_:
raise ValueError("%r too long" % (val,))
if isinstance(val, unicode):
target = self._buffer
else:
target = self
for i in range(len(val)):
target[i] = val[i]
if len(val) < self._length_:
target[len(val)] = u'\x00'
res.value = property(getvalue, setvalue)
if '_length_' in typedict:
res._ffishape_ = (ffiarray, typedict['_length_'])
res._fficompositesize_ = res._sizeofinstances()
else:
res._ffiarray = None
return res
from_address = cdata_from_address
def _sizeofinstances(self):
size, alignment = self._ffiarray.size_alignment(self._length_)
return size
def _alignmentofinstances(self):
return self._type_._alignmentofinstances()
def _CData_output(self, resarray, base=None, index=-1):
# this seems to be a string if we're array of char, surprise!
from ctypes import c_char, c_wchar
if self._type_ is c_char:
return _rawffi.charp2string(resarray.buffer, self._length_)
if self._type_ is c_wchar:
return _rawffi.wcharp2unicode(resarray.buffer, self._length_)
res = self.__new__(self)
ffiarray = self._ffiarray.fromaddress(resarray.buffer, self._length_)
res._buffer = ffiarray
res._base = base
res._index = index
return res
def _CData_retval(self, resbuffer):
raise NotImplementedError
def from_param(self, value):
# array accepts very strange parameters as part of structure
# or function argument...
from ctypes import c_char, c_wchar
if issubclass(self._type_, (c_char, c_wchar)):
if isinstance(value, basestring):
if len(value) > self._length_:
raise ValueError("Invalid length")
value = self(*value)
elif not isinstance(value, self):
raise TypeError("expected string or Unicode object, %s found"
% (value.__class__.__name__,))
else:
if isinstance(value, tuple):
if len(value) > self._length_:
raise RuntimeError("Invalid length")
value = self(*value)
return _CDataMeta.from_param(self, value)
def array_get_slice_params(self, index):
if hasattr(self, '_length_'):
start, stop, step = index.indices(self._length_)
else:
step = index.step
if step is None:
step = 1
start = index.start
stop = index.stop
if start is None:
if step > 0:
start = 0
else:
raise ValueError("slice start is required for step < 0")
if stop is None:
raise ValueError("slice stop is required")
return start, stop, step
def array_slice_setitem(self, index, value):
start, stop, step = self._get_slice_params(index)
if ((step < 0 and stop >= start) or
(step > 0 and start >= stop)):
slicelength = 0
elif step < 0:
slicelength = (stop - start + 1) / step + 1
else:
slicelength = (stop - start - 1) / step + 1;
if slicelength != len(value):
raise ValueError("Can only assign slices of the same length")
for i, j in enumerate(range(start, stop, step)):
self[j] = value[i]
def array_slice_getitem(self, index):
start, stop, step = self._get_slice_params(index)
l = [self[i] for i in range(start, stop, step)]
letter = getattr(self._type_, '_type_', None)
if letter == 'c':
return "".join(l)
if letter == 'u':
return u"".join(l)
return l
class Array(_CData):
__metaclass__ = ArrayMeta
_ffiargshape_ = 'P'
def __init__(self, *args):
if not hasattr(self, '_buffer'):
self._buffer = self._ffiarray(self._length_, autofree=True)
for i, arg in enumerate(args):
self[i] = arg
def _fix_index(self, index):
if index < 0:
index += self._length_
if 0 <= index < self._length_:
return index
else:
raise IndexError
_get_slice_params = array_get_slice_params
_slice_getitem = array_slice_getitem
_slice_setitem = array_slice_setitem
def _subarray(self, index):
"""Return a _rawffi array of length 1 whose address is the same as
the index'th item of self."""
address = self._buffer.itemaddress(index)
return self._ffiarray.fromaddress(address, 1)
def __setitem__(self, index, value):
if isinstance(index, slice):
self._slice_setitem(index, value)
return
index = self._fix_index(index)
cobj = self._type_.from_param(value)
if ensure_objects(cobj) is not None:
store_reference(self, index, cobj._objects)
arg = cobj._get_buffer_value()
if self._type_._fficompositesize_ is None:
self._buffer[index] = arg
# something more sophisticated, cannot set field directly
else:
from ctypes import memmove
dest = self._buffer.itemaddress(index)
memmove(dest, arg, self._type_._fficompositesize_)
def __getitem__(self, index):
if isinstance(index, slice):
return self._slice_getitem(index)
index = self._fix_index(index)
return self._type_._CData_output(self._subarray(index), self, index)
def __len__(self):
return self._length_
def _get_buffer_for_param(self):
return CArgObject(self, self._buffer.byptr())
def _get_buffer_value(self):
return self._buffer.buffer
def _to_ffi_param(self):
return self._get_buffer_value()
def _as_ffi_pointer_(self, ffitype):
return as_ffi_pointer(self, ffitype)
ARRAY_CACHE = {}
def create_array_type(base, length):
if not isinstance(length, (int, long)):
raise TypeError("Can't multiply a ctypes type by a non-integer")
if length < 0:
raise ValueError("Array length must be >= 0")
key = (base, length)
try:
return ARRAY_CACHE[key]
except KeyError:
name = "%s_Array_%d" % (base.__name__, length)
tpdict = dict(
_length_ = length,
_type_ = base
)
cls = ArrayMeta(name, (Array,), tpdict)
cls._ffiargtype = _ffi.types.Pointer(base.get_ffi_argtype())
ARRAY_CACHE[key] = cls
return cls
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