gns3-server/gns3server/utils/asyncio/serial.py

141 lines
3.6 KiB
Python

#!/usr/bin/env python
#
# Copyright (C) 2016 GNS3 Technologies Inc.
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program. If not, see <http://www.gnu.org/licenses/>.
import sys
import asyncio
from gns3server.utils.asyncio import wait_for_file_creation, wait_for_named_pipe_creation
from gns3server.compute.error import NodeError
"""
This module handle connection to unix socket or Windows named pipe
"""
if sys.platform.startswith("win"):
import win32file
import win32pipe
import msvcrt
class SerialReaderWriterProtocol(asyncio.Protocol):
def __init__(self):
self._output = asyncio.StreamReader()
self._closed = False
self.transport = None
def read(self, n=-1):
return self._output.read(n=n)
def at_eof(self):
return self._output.at_eof()
def write(self, data):
if self.transport:
self.transport.write(data)
async def drain(self):
pass
def connection_made(self, transport):
self.transport = transport
def data_received(self, data):
if not self._closed:
self._output.feed_data(data)
def close(self):
self._closed = True
self._output.feed_eof()
class WindowsPipe:
"""
Write input and output stream to the same object
"""
def __init__(self, path):
self._handle = open(path, "a+b")
self._pipe = msvcrt.get_osfhandle(self._handle.fileno())
async def read(self, n=-1):
(read, num_avail, num_message) = win32pipe.PeekNamedPipe(self._pipe, 0)
if num_avail > 0:
(error_code, output) = win32file.ReadFile(self._pipe, num_avail, None)
return output
await asyncio.sleep(0.01)
return b""
def at_eof(self):
return False
def write(self, data):
win32file.WriteFile(self._pipe, data)
async def drain(self):
return
def close(self):
pass
async def _asyncio_open_serial_windows(path):
"""
Open a windows named pipe
:returns: An IO like object
"""
try:
await wait_for_named_pipe_creation(path)
except asyncio.TimeoutError:
raise NodeError('Pipe file "{}" is missing'.format(path))
return WindowsPipe(path)
async def _asyncio_open_serial_unix(path):
"""
Open a unix socket or a windows named pipe
:returns: An IO like object
"""
try:
# wait for VM to create the pipe file.
await wait_for_file_creation(path)
except asyncio.TimeoutError:
raise NodeError('Pipe file "{}" is missing'.format(path))
output = SerialReaderWriterProtocol()
try:
await asyncio.get_event_loop().create_unix_connection(lambda: output, path)
except ConnectionRefusedError:
raise NodeError('Can\'t open pipe file "{}"'.format(path))
return output
async def asyncio_open_serial(path):
"""
Open a unix socket or a windows named pipe
:returns: An IO like object
"""
if sys.platform.startswith("win"):
return (await _asyncio_open_serial_windows(path))
else:
return (await _asyncio_open_serial_unix(path))