| # Copyright (c) 2012 The Chromium Authors. All rights reserved. |
| # Use of this source code is governed by a BSD-style license that can be |
| # found in the LICENSE file. |
| |
| # This file is based on gdb_rsp.py file from NaCl repository. |
| |
| import re |
| import socket |
| import time |
| |
| |
| def RspChecksum(data): |
| checksum = 0 |
| for char in data: |
| checksum = (checksum + ord(char)) % 0x100 |
| return checksum |
| |
| |
| class EofOnReplyException(Exception): |
| |
| pass |
| |
| |
| class GdbRspConnection(object): |
| |
| def __init__(self, addr): |
| self._socket = self._Connect(addr) |
| |
| def _Connect(self, addr): |
| # We have to poll because we do not know when sel_ldr has |
| # successfully done bind() on the TCP port. This is inherently |
| # unreliable. |
| # TODO(mseaborn): Add a more reliable connection mechanism to |
| # sel_ldr's debug stub. |
| timeout_in_seconds = 10 |
| poll_time_in_seconds = 0.1 |
| for i in xrange(int(timeout_in_seconds / poll_time_in_seconds)): |
| # On Mac OS X, we have to create a new socket FD for each retry. |
| sock = socket.socket() |
| try: |
| sock.connect(addr) |
| except socket.error: |
| # Retry after a delay. |
| time.sleep(poll_time_in_seconds) |
| else: |
| return sock |
| raise Exception('Could not connect to sel_ldr\'s debug stub in %i seconds' |
| % timeout_in_seconds) |
| |
| def _GetReply(self): |
| reply = '' |
| while True: |
| data = self._socket.recv(1024) |
| if len(data) == 0: |
| if reply == '+': |
| raise EofOnReplyException() |
| raise AssertionError('EOF on socket reached with ' |
| 'incomplete reply message: %r' % reply) |
| reply += data |
| if '#' in data: |
| break |
| match = re.match('\+\$([^#]*)#([0-9a-fA-F]{2})$', reply) |
| if match is None: |
| raise AssertionError('Unexpected reply message: %r' % reply) |
| reply_body = match.group(1) |
| checksum = match.group(2) |
| expected_checksum = '%02x' % RspChecksum(reply_body) |
| if checksum != expected_checksum: |
| raise AssertionError('Bad RSP checksum: %r != %r' % |
| (checksum, expected_checksum)) |
| # Send acknowledgement. |
| self._socket.send('+') |
| return reply_body |
| |
| # Send an rsp message, but don't wait for or expect a reply. |
| def RspSendOnly(self, data): |
| msg = '$%s#%02x' % (data, RspChecksum(data)) |
| return self._socket.send(msg) |
| |
| def RspRequest(self, data): |
| self.RspSendOnly(data) |
| return self._GetReply() |
| |
| def RspInterrupt(self): |
| self._socket.send('\x03') |
| return self._GetReply() |