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Diffstat (limited to 'python/qemu/console_socket.py')
-rw-r--r-- | python/qemu/console_socket.py | 110 |
1 files changed, 110 insertions, 0 deletions
diff --git a/python/qemu/console_socket.py b/python/qemu/console_socket.py new file mode 100644 index 0000000000..830cb7c628 --- /dev/null +++ b/python/qemu/console_socket.py @@ -0,0 +1,110 @@ +#!/usr/bin/env python3 +# +# This python module implements a ConsoleSocket object which is +# designed always drain the socket itself, and place +# the bytes into a in memory buffer for later processing. +# +# Optionally a file path can be passed in and we will also +# dump the characters to this file for debug. +# +# Copyright 2020 Linaro +# +# Authors: +# Robert Foley <robert.foley@linaro.org> +# +# This code is licensed under the GPL version 2 or later. See +# the COPYING file in the top-level directory. +# +import asyncore +import socket +import threading +import io +import os +import sys +from collections import deque +import time +import traceback + +class ConsoleSocket(asyncore.dispatcher): + + def __init__(self, address, file=None): + self._recv_timeout_sec = 300 + self._buffer = deque() + self._asyncore_thread = None + self._sock = socket.socket(socket.AF_UNIX, socket.SOCK_STREAM) + self._sock.connect(address) + self._logfile = None + if file: + self._logfile = open(file, "w") + asyncore.dispatcher.__init__(self, sock=self._sock) + self._open = True + self._thread_start() + + def _thread_start(self): + """Kick off a thread to wait on the asyncore.loop""" + if self._asyncore_thread is not None: + return + self._asyncore_thread = threading.Thread(target=asyncore.loop, + kwargs={'timeout':1}) + self._asyncore_thread.daemon = True + self._asyncore_thread.start() + + def handle_close(self): + """redirect close to base class""" + # Call the base class close, but not self.close() since + # handle_close() occurs in the context of the thread which + # self.close() attempts to join. + asyncore.dispatcher.close(self) + + def close(self): + """Close the base object and wait for the thread to terminate""" + if self._open: + self._open = False + asyncore.dispatcher.close(self) + if self._asyncore_thread is not None: + thread, self._asyncore_thread = self._asyncore_thread, None + thread.join() + if self._logfile: + self._logfile.close() + self._logfile = None + + def handle_read(self): + """process arriving characters into in memory _buffer""" + try: + data = asyncore.dispatcher.recv(self, 1) + # latin1 is needed since there are some chars + # we are receiving that cannot be encoded to utf-8 + # such as 0xe2, 0x80, 0xA6. + string = data.decode("latin1") + except: + print("Exception seen.") + traceback.print_exc() + return + if self._logfile: + self._logfile.write("{}".format(string)) + self._logfile.flush() + for c in string: + self._buffer.extend(c) + + def recv(self, n=1, sleep_delay_s=0.1): + """Return chars from in memory buffer""" + start_time = time.time() + while len(self._buffer) < n: + time.sleep(sleep_delay_s) + elapsed_sec = time.time() - start_time + if elapsed_sec > self._recv_timeout_sec: + raise socket.timeout + chars = ''.join([self._buffer.popleft() for i in range(n)]) + # We choose to use latin1 to remain consistent with + # handle_read() and give back the same data as the user would + # receive if they were reading directly from the + # socket w/o our intervention. + return chars.encode("latin1") + + def set_blocking(self): + """Maintain compatibility with socket API""" + pass + + def settimeout(self, seconds): + """Set current timeout on recv""" + self._recv_timeout_sec = seconds |