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from pypy.interpreter.baseobjspace import W_Root
from pypy.interpreter.error import OperationError, oefmt
from pypy.interpreter.gateway import unwrap_spec, interp2app
from pypy.interpreter.typedef import TypeDef, make_weakref_descr
from pypy.module._cffi_backend import cdataobj, ctypeptr, ctypearray
from pypy.module._cffi_backend import ctypestruct
from pypy.interpreter.buffer import SimpleView
from rpython.rlib.buffer import RawBuffer
from rpython.rtyper.annlowlevel import llstr
from rpython.rtyper.lltypesystem import rffi
from rpython.rtyper.lltypesystem.rstr import copy_string_to_raw
class LLBuffer(RawBuffer):
_immutable_ = True
def __init__(self, raw_cdata, size):
self.raw_cdata = raw_cdata
self.size = size
self.readonly = False
def getlength(self):
return self.size
def getitem(self, index):
return self.raw_cdata[index]
def setitem(self, index, char):
self.raw_cdata[index] = char
def get_raw_address(self):
return self.raw_cdata
def getslice(self, start, stop, step, size):
if step == 1:
return rffi.charpsize2str(rffi.ptradd(self.raw_cdata, start), size)
return RawBuffer.getslice(self, start, stop, step, size)
def setslice(self, start, string):
raw_cdata = rffi.ptradd(self.raw_cdata, start)
copy_string_to_raw(llstr(string), raw_cdata, 0, len(string))
class MiniBuffer(W_Root):
def __init__(self, buffer, keepalive=None):
self.buffer = buffer
self.keepalive = keepalive
def buffer_w(self, space, flags):
return SimpleView(self.buffer)
def descr_len(self, space):
return space.newint(self.buffer.getlength())
def descr_getitem(self, space, w_index):
start, stop, step, size = space.decode_index4(w_index,
self.buffer.getlength())
if step == 0:
return space.newbytes(self.buffer.getitem(start))
res = self.buffer.getslice(start, stop, step, size)
return space.newbytes(res)
def descr_setitem(self, space, w_index, w_newstring):
start, stop, step, size = space.decode_index4(w_index,
self.buffer.getlength())
if step not in (0, 1):
raise oefmt(space.w_NotImplementedError, "")
value = space.buffer_w(w_newstring, space.BUF_CONTIG_RO).as_readbuf()
if value.getlength() != size:
raise oefmt(space.w_ValueError,
"cannot modify size of memoryview object")
if step == 0: # index only
self.buffer.setitem(start, value.getitem(0))
elif step == 1:
self.buffer.setslice(start, value.as_str())
def _comparison_helper(self, space, w_other, mode):
if space.isinstance_w(w_other, space.w_unicode):
return space.w_NotImplemented
try:
other_buf = space.readbuf_w(w_other)
except OperationError as e:
if e.async(space):
raise
return space.w_NotImplemented
my_buf = self.buffer
my_len = len(my_buf)
other_len = len(other_buf)
if other_len != my_len:
if mode == 'E':
return space.w_False
if mode == 'N':
return space.w_True
cmp = _memcmp(my_buf, other_buf, min(my_len, other_len))
if cmp == 0:
if my_len < other_len:
cmp = -1
elif my_len > other_len:
cmp = 1
if mode == 'L': res = cmp < 0
elif mode == 'l': res = cmp <= 0
elif mode == 'E': res = cmp == 0
elif mode == 'N': res = cmp != 0
elif mode == 'G': res = cmp > 0
elif mode == 'g': res = cmp >= 0
else: raise AssertionError
return space.newbool(res)
def descr_eq(self, space, w_other):
return self._comparison_helper(space, w_other, 'E')
def descr_ne(self, space, w_other):
return self._comparison_helper(space, w_other, 'N')
def descr_lt(self, space, w_other):
return self._comparison_helper(space, w_other, 'L')
def descr_le(self, space, w_other):
return self._comparison_helper(space, w_other, 'l')
def descr_gt(self, space, w_other):
return self._comparison_helper(space, w_other, 'G')
def descr_ge(self, space, w_other):
return self._comparison_helper(space, w_other, 'g')
def _memcmp(buf1, buf2, length):
# XXX very slow
for i in range(length):
if buf1[i] < buf2[i]:
return -1
if buf1[i] > buf2[i]:
return 1
return 0
@unwrap_spec(w_cdata=cdataobj.W_CData, size=int)
def MiniBuffer___new__(space, w_subtype, w_cdata, size=-1):
ctype = w_cdata.ctype
if isinstance(ctype, ctypeptr.W_CTypePointer):
if size < 0:
structobj = w_cdata.get_structobj()
if (structobj is not None and
isinstance(structobj.ctype, ctypestruct.W_CTypeStructOrUnion)):
size = structobj._sizeof()
if size < 0:
size = ctype.ctitem.size
elif isinstance(ctype, ctypearray.W_CTypeArray):
if size < 0:
size = w_cdata._sizeof()
else:
raise oefmt(space.w_TypeError,
"expected a pointer or array cdata, got '%s'", ctype.name)
if size < 0:
raise oefmt(space.w_TypeError,
"don't know the size pointed to by '%s'", ctype.name)
ptr = w_cdata.unsafe_escaping_ptr() # w_cdata kept alive by MiniBuffer()
return MiniBuffer(LLBuffer(ptr, size), w_cdata)
MiniBuffer.typedef = TypeDef(
"_cffi_backend.buffer", None, None, "read-write",
__new__ = interp2app(MiniBuffer___new__),
__len__ = interp2app(MiniBuffer.descr_len),
__getitem__ = interp2app(MiniBuffer.descr_getitem),
__setitem__ = interp2app(MiniBuffer.descr_setitem),
__eq__ = interp2app(MiniBuffer.descr_eq),
__ne__ = interp2app(MiniBuffer.descr_ne),
__lt__ = interp2app(MiniBuffer.descr_lt),
__le__ = interp2app(MiniBuffer.descr_le),
__gt__ = interp2app(MiniBuffer.descr_gt),
__ge__ = interp2app(MiniBuffer.descr_ge),
__weakref__ = make_weakref_descr(MiniBuffer),
__doc__ = """ffi.buffer(cdata[, byte_size]):
Return a read-write buffer object that references the raw C data
pointed to by the given 'cdata'. The 'cdata' must be a pointer or an
array. Can be passed to functions expecting a buffer, or directly
manipulated with:
buf[:] get a copy of it in a regular string, or
buf[idx] as a single character
buf[:] = ...
buf[idx] = ... change the content
""",
)
MiniBuffer.typedef.acceptable_as_base_class = False
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