buftools.py 文件源码

def _get_buffer(self, view, flags):
        from ctypes import addressof
        if (flags & PyBUF_WRITABLE) == PyBUF_WRITABLE and self.readonly:
            raise BufferError("buffer is read-only")
        if ((flags & PyBUF_C_CONTIGUOUS) == PyBUF_C_CONTIGUOUS and
            not self.is_contiguous('C')):
            raise BufferError("data is not C contiguous")
        if ((flags & PyBUF_F_CONTIGUOUS) == PyBUF_F_CONTIGUOUS and
            not self.is_contiguous('F')):
            raise BufferError("data is not F contiguous")
        if ((flags & PyBUF_ANY_CONTIGUOUS) == PyBUF_ANY_CONTIGUOUS and
            not self.is_contiguous('A')):
            raise BufferError("data is not contiguous")
        view.buf = self.buf
        view.readonly = self.readonly
        view.len = self.len
        if flags | PyBUF_WRITABLE == PyBUF_WRITABLE:
            view.ndim = 0
        else:
            view.ndim = self.ndim
        view.itemsize = self.itemsize
        if (flags & PyBUF_FORMAT) == PyBUF_FORMAT:
            view.format = addressof(self._format)
        else:
            view.format = None
        if (flags & PyBUF_ND) == PyBUF_ND:
            view.shape = addressof(self._shape)
        elif self.is_contiguous('C'):
            view.shape = None
        else:
            raise BufferError(
                "shape required for {} dimensional data".format(self.ndim))
        if (flags & PyBUF_STRIDES) == PyBUF_STRIDES:
            view.strides = ctypes.addressof(self._strides)
        elif view.shape is None or self.is_contiguous('C'):
            view.strides = None
        else:
            raise BufferError("strides required for none C contiguous data")
        view.suboffsets = None
        view.internal = None
        view.obj = self