securetransport.py 文件源码

def recv_into(self, buffer, nbytes=None):
        # Read short on EOF.
        if self._closed:
            return 0

        if nbytes is None:
            nbytes = len(buffer)

        buffer = (ctypes.c_char * nbytes).from_buffer(buffer)
        processed_bytes = ctypes.c_size_t(0)

        with self._raise_on_error():
            result = Security.SSLRead(
                self.context, buffer, nbytes, ctypes.byref(processed_bytes)
            )

        # There are some result codes that we want to treat as "not always
        # errors". Specifically, those are errSSLWouldBlock,
        # errSSLClosedGraceful, and errSSLClosedNoNotify.
        if (result == SecurityConst.errSSLWouldBlock):
            # If we didn't process any bytes, then this was just a time out.
            # However, we can get errSSLWouldBlock in situations when we *did*
            # read some data, and in those cases we should just read "short"
            # and return.
            if processed_bytes.value == 0:
                # Timed out, no data read.
                raise socket.timeout("recv timed out")
        elif result in (SecurityConst.errSSLClosedGraceful, SecurityConst.errSSLClosedNoNotify):
            # The remote peer has closed this connection. We should do so as
            # well. Note that we don't actually return here because in
            # principle this could actually be fired along with return data.
            # It's unlikely though.
            self.close()
        else:
            _assert_no_error(result)

        # Ok, we read and probably succeeded. We should return whatever data
        # was actually read.
        return processed_bytes.value