We add the ConsoleSocket object, which has a socket interface
and which will consume all arriving characters on the
socket, placing them into an in memory buffer.
This will also provide those chars via recv() as
would a regular socket.
ConsoleSocket also has the option of dumping
the console bytes to a log file.
We also give QEMUMachine the option of using ConsoleSocket
to drain and to use for logging console to a file.
By default QEMUMachine does not use ConsoleSocket.
This is added in preparation for use by basevm.py in a later commit.
This is a workaround we found was needed for basevm.py since
there is a known issue where QEMU will hang waiting
for console characters to be consumed.
Cc: Eduardo Habkost <ehabk...@redhat.com>
Cc: Cleber Rosa <cr...@redhat.com>
Signed-off-by: Robert Foley <robert.fo...@linaro.org>
Reviewed-by: Peter Puhov <peter.pu...@linaro.org>
Acked-by: Alex Bennée <alex.ben...@linaro.org>
---
python/qemu/console_socket.py | 118 ++++++++++++++++++++++++++++++++++
python/qemu/machine.py | 23 +++++--
2 files changed, 137 insertions(+), 4 deletions(-)
create mode 100644 python/qemu/console_socket.py
diff --git a/python/qemu/console_socket.py b/python/qemu/console_socket.py
new file mode 100644
index 0000000000..2fe1c20d64
--- /dev/null
+++ b/python/qemu/console_socket.py
@@ -0,0 +1,118 @@
+#!/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.fo...@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._thread_start()
+ self._open = True
+
+ 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.append(c)
+
+ def recv(self, n=1):
+ """Return chars from in memory buffer"""
+ start_time = time.time()
+ while len(self._buffer) < n:
+ time.sleep(0.1)
+ 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
+
+class ByteBuffer(deque):
+ """Simple in memory buffer with read/write interface"""
+ def write(self, bytes):
+ for i in bytes:
+ self.append(i)
+ def read(self, n):
+ return ''.join([self.popleft() for i in range(n)])
diff --git a/python/qemu/machine.py b/python/qemu/machine.py
index b9a98e2c86..ee9c337f55 100644
--- a/python/qemu/machine.py
+++ b/python/qemu/machine.py
@@ -24,6 +24,7 @@ import subprocess
import shutil
import socket
import tempfile
+from qemu.console_socket import ConsoleSocket
from . import qmp
@@ -71,7 +72,8 @@ class QEMUMachine(object):
def __init__(self, binary, args=None, wrapper=None, name=None,
test_dir="/var/tmp", monitor_address=None,
- socket_scm_helper=None, sock_dir=None):
+ socket_scm_helper=None, sock_dir=None,
+ drain_console=False, console_log=None):
'''
Initialize a QEMUMachine
@@ -82,6 +84,9 @@ class QEMUMachine(object):
@param test_dir: where to create socket and log file
@param monitor_address: address for QMP monitor
@param socket_scm_helper: helper program, required for send_fd_scm()
+ @param sock_dir: where to create socket (overrides test_dir for sock)
+ @param console_log: (optional) path to console log file
+ @param drain_console: (optional) True to drain console socket to buffer
@note: Qemu process is not started until launch() is used.
'''
if args is None:
@@ -118,6 +123,12 @@ class QEMUMachine(object):
self._console_address = None
self._console_socket = None
self._remove_files = []
+ self._console_log_path = console_log
+ if self._console_log_path:
+ # In order to log the console, buffering needs to be enabled.
+ self._drain_console = True
+ else:
+ self._drain_console = drain_console
# just in case logging wasn't configured by the main script:
logging.basicConfig()
@@ -568,7 +579,11 @@ class QEMUMachine(object):
Returns a socket connected to the console
"""
if self._console_socket is None:
- self._console_socket = socket.socket(socket.AF_UNIX,
- socket.SOCK_STREAM)
- self._console_socket.connect(self._console_address)
+ if self._drain_console:
+ self._console_socket = ConsoleSocket(self._console_address,
+
file=self._console_log_path)
+ else:
+ self._console_socket = socket.socket(socket.AF_UNIX,
+ socket.SOCK_STREAM)
+ self._console_socket.connect(self._console_address)
return self._console_socket
--
2.17.1
