def from_buffer(space, w_ctype, w_x, require_writable=0):
from pypy.module._cffi_backend import ctypearray
if not isinstance(w_ctype, ctypearray.W_CTypeArray):
raise oefmt(space.w_TypeError, "expected an array ctype, got '%s'",
w_ctype.name)
if space.isinstance_w(w_x, space.w_unicode):
raise oefmt(
space.w_TypeError,
"from_buffer() cannot return the address of a unicode object")
if require_writable:
buf = _fetch_as_write_buffer(space, w_x)
else:
buf = _fetch_as_read_buffer(space, w_x)
if space.isinstance_w(w_x, space.w_bytes):
_cdata = get_raw_address_of_string(space, w_x)
else:
try:
_cdata = buf.get_raw_address()
except ValueError:
raise oefmt(
space.w_TypeError,
"from_buffer() got a '%T' object, which supports the "
"buffer interface but cannot be rendered as a plain "
"raw address on PyPy", w_x)
#
buffersize = buf.getlength()
arraylength = w_ctype.length
if arraylength >= 0:
# it's an array with a fixed length; make sure that the
# buffer contains enough bytes.
if buffersize < w_ctype.size:
raise oefmt(space.w_ValueError,
"buffer is too small (%d bytes) for '%s' (%d bytes)",
buffersize, w_ctype.name, w_ctype.size)
else:
# it's an open 'array[]'
itemsize = w_ctype.ctitem.size
if itemsize == 1:
# fast path, performance only
arraylength = buffersize
elif itemsize > 0:
# give it as many items as fit the buffer. Ignore a
# partial last element.
arraylength = buffersize / itemsize
else:
# it's an array 'empty[]'. Unsupported obscure case:
# the problem is that setting the length of the result
# to anything large (like SSIZE_T_MAX) is dangerous,
# because if someone tries to loop over it, it will
# turn effectively into an infinite loop.
raise oefmt(
space.w_ZeroDivisionError,
"from_buffer('%s', ..): the actual length of the array "
"cannot be computed", w_ctype.name)
#
return cdataobj.W_CDataFromBuffer(space, _cdata, arraylength, w_ctype, buf,
w_x)
def _from_buffer(space, w_ctype, w_x):
if space.isinstance_w(w_x, space.w_unicode):
raise oefmt(space.w_TypeError,
"from_buffer() cannot return the address a unicode")
buf = _fetch_as_read_buffer(space, w_x)
if space.isinstance_w(w_x, space.w_bytes):
_cdata = get_raw_address_of_string(space, w_x)
else:
try:
_cdata = buf.get_raw_address()
except ValueError:
raise oefmt(space.w_TypeError,
"from_buffer() got a '%T' object, which supports the "
"buffer interface but cannot be rendered as a plain "
"raw address on PyPy", w_x)
#
return cdataobj.W_CDataFromBuffer(space, _cdata, w_ctype, buf, w_x)
def from_buffer(space, w_ctype, w_x):
from pypy.module._cffi_backend import ctypearray, ctypeprim
#
if (not isinstance(w_ctype, ctypearray.W_CTypeArray) or not isinstance(
w_ctype.ctptr.ctitem, ctypeprim.W_CTypePrimitiveChar)):
raise oefmt(space.w_TypeError, "needs 'char[]', got '%s'",
w_ctype.name)
#
buf = _fetch_as_read_buffer(space, w_x)
try:
_cdata = buf.get_raw_address()
except ValueError:
raise oefmt(
space.w_TypeError,
"from_buffer() got a '%T' object, which supports the "
"buffer interface but cannot be rendered as a plain "
"raw address on PyPy", w_x)
#
return cdataobj.W_CDataFromBuffer(space, _cdata, w_ctype, buf, w_x)
# ____________________________________________________________
@unwrap_spec(w_ctype=ctypeobj.W_CType)
def from_buffer(space, w_ctype, w_x):
from pypy.module._cffi_backend import ctypearray, ctypeprim
#
if (not isinstance(w_ctype, ctypearray.W_CTypeArray) or not isinstance(
w_ctype.ctptr.ctitem, ctypeprim.W_CTypePrimitiveChar)):
raise oefmt(space.w_TypeError, "needs 'char[]', got '%s'",
w_ctype.name)
#
# xxx do we really need to implement the same mess as in CPython 2.7
# w.r.t. buffers and memoryviews??
try:
buf = space.readbuf_w(w_x)
except OperationError, e:
if not e.match(space, space.w_TypeError):
raise
buf = space.buffer_w(w_x, space.BUF_SIMPLE)
try:
_cdata = buf.get_raw_address()
except ValueError:
raise oefmt(
space.w_TypeError,
"from_buffer() got a '%T' object, which supports the "
"buffer interface but cannot be rendered as a plain "
"raw address on PyPy", w_x)
#
return cdataobj.W_CDataFromBuffer(space, _cdata, w_ctype, buf, w_x)