blob: b5fed6c9fecb763e2aed48b5bf58b6295f4b00e2 [file] [log] [blame]
#
# Copyright (C) 2013 Intel Corporation
#
# SPDX-License-Identifier: MIT
#
# This module provides a class for starting qemu images using runqemu.
# It's used by testimage.bbclass.
import subprocess
import os
import sys
import time
import signal
import re
import socket
import select
import errno
import string
import threading
import codecs
import logging
import tempfile
from oeqa.utils.dump import HostDumper
from collections import defaultdict
import importlib
# Get Unicode non printable control chars
control_range = list(range(0,32))+list(range(127,160))
control_chars = [chr(x) for x in control_range
if chr(x) not in string.printable]
re_control_char = re.compile('[%s]' % re.escape("".join(control_chars)))
class QemuRunner:
def __init__(self, machine, rootfs, display, tmpdir, deploy_dir_image, logfile, boottime, dump_dir, dump_host_cmds,
use_kvm, logger, use_slirp=False, serial_ports=2, boot_patterns = defaultdict(str), use_ovmf=False, workdir=None, tmpfsdir=None):
# Popen object for runqemu
self.runqemu = None
self.runqemu_exited = False
# pid of the qemu process that runqemu will start
self.qemupid = None
# target ip - from the command line or runqemu output
self.ip = None
# host ip - where qemu is running
self.server_ip = None
# target ip netmask
self.netmask = None
self.machine = machine
self.rootfs = rootfs
self.display = display
self.tmpdir = tmpdir
self.deploy_dir_image = deploy_dir_image
self.logfile = logfile
self.boottime = boottime
self.logged = False
self.thread = None
self.use_kvm = use_kvm
self.use_ovmf = use_ovmf
self.use_slirp = use_slirp
self.serial_ports = serial_ports
self.msg = ''
self.boot_patterns = boot_patterns
self.tmpfsdir = tmpfsdir
self.runqemutime = 300
if not workdir:
workdir = os.getcwd()
self.qemu_pidfile = workdir + '/pidfile_' + str(os.getpid())
self.host_dumper = HostDumper(dump_host_cmds, dump_dir)
self.monitorpipe = None
self.logger = logger
# Whether we're expecting an exit and should show related errors
self.canexit = False
# Enable testing other OS's
# Set commands for target communication, and default to Linux ALWAYS
# Other OS's or baremetal applications need to provide their
# own implementation passing it through QemuRunner's constructor
# or by passing them through TESTIMAGE_BOOT_PATTERNS[flag]
# provided variables, where <flag> is one of the mentioned below.
accepted_patterns = ['search_reached_prompt', 'send_login_user', 'search_login_succeeded', 'search_cmd_finished']
default_boot_patterns = defaultdict(str)
# Default to the usual paterns used to communicate with the target
default_boot_patterns['search_reached_prompt'] = ' login:'
default_boot_patterns['send_login_user'] = 'root\n'
default_boot_patterns['search_login_succeeded'] = r"root@[a-zA-Z0-9\-]+:~#"
default_boot_patterns['search_cmd_finished'] = r"[a-zA-Z0-9]+@[a-zA-Z0-9\-]+:~#"
# Only override patterns that were set e.g. login user TESTIMAGE_BOOT_PATTERNS[send_login_user] = "webserver\n"
for pattern in accepted_patterns:
if not self.boot_patterns[pattern]:
self.boot_patterns[pattern] = default_boot_patterns[pattern]
def create_socket(self):
try:
sock = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
sock.setblocking(0)
sock.bind(("127.0.0.1",0))
sock.listen(2)
port = sock.getsockname()[1]
self.logger.debug("Created listening socket for qemu serial console on: 127.0.0.1:%s" % port)
return (sock, port)
except socket.error:
sock.close()
raise
def decode_qemulog(self, todecode):
# Sanitize the data received from qemu as it may contain control characters
msg = todecode.decode("utf-8", errors='ignore')
msg = re_control_char.sub('', msg)
return msg
def log(self, msg):
if self.logfile:
msg = self.decode_qemulog(msg)
self.msg += msg
with codecs.open(self.logfile, "a", encoding="utf-8") as f:
f.write("%s" % msg)
def getOutput(self, o):
import fcntl
fl = fcntl.fcntl(o, fcntl.F_GETFL)
fcntl.fcntl(o, fcntl.F_SETFL, fl | os.O_NONBLOCK)
try:
return os.read(o.fileno(), 1000000).decode("utf-8")
except BlockingIOError:
return ""
def handleSIGCHLD(self, signum, frame):
if self.runqemu and self.runqemu.poll():
if self.runqemu.returncode:
self.logger.error('runqemu exited with code %d' % self.runqemu.returncode)
self.logger.error('Output from runqemu:\n%s' % self.getOutput(self.runqemu.stdout))
self.stop()
self._dump_host()
def start(self, qemuparams = None, get_ip = True, extra_bootparams = None, runqemuparams='', launch_cmd=None, discard_writes=True):
env = os.environ.copy()
if self.display:
env["DISPLAY"] = self.display
# Set this flag so that Qemu doesn't do any grabs as SDL grabs
# interact badly with screensavers.
env["QEMU_DONT_GRAB"] = "1"
if not os.path.exists(self.rootfs):
self.logger.error("Invalid rootfs %s" % self.rootfs)
return False
if not os.path.exists(self.tmpdir):
self.logger.error("Invalid TMPDIR path %s" % self.tmpdir)
return False
else:
env["OE_TMPDIR"] = self.tmpdir
if not os.path.exists(self.deploy_dir_image):
self.logger.error("Invalid DEPLOY_DIR_IMAGE path %s" % self.deploy_dir_image)
return False
else:
env["DEPLOY_DIR_IMAGE"] = self.deploy_dir_image
if self.tmpfsdir:
env["RUNQEMU_TMPFS_DIR"] = self.tmpfsdir
if not launch_cmd:
launch_cmd = 'runqemu %s' % ('snapshot' if discard_writes else '')
if self.use_kvm:
self.logger.debug('Using kvm for runqemu')
launch_cmd += ' kvm'
else:
self.logger.debug('Not using kvm for runqemu')
if not self.display:
launch_cmd += ' nographic'
if self.use_slirp:
launch_cmd += ' slirp'
if self.use_ovmf:
launch_cmd += ' ovmf'
launch_cmd += ' %s %s' % (runqemuparams, self.machine)
if self.rootfs.endswith('.vmdk'):
self.logger.debug('Bypassing VMDK rootfs for runqemu')
else:
launch_cmd += ' %s' % (self.rootfs)
return self.launch(launch_cmd, qemuparams=qemuparams, get_ip=get_ip, extra_bootparams=extra_bootparams, env=env)
def launch(self, launch_cmd, get_ip = True, qemuparams = None, extra_bootparams = None, env = None):
# use logfile to determine the recipe-sysroot-native path and
# then add in the site-packages path components and add that
# to the python sys.path so qmp.py can be found.
python_path = os.path.dirname(os.path.dirname(self.logfile))
python_path += "/recipe-sysroot-native/usr/lib/qemu-python"
sys.path.append(python_path)
importlib.invalidate_caches()
try:
qmp = importlib.import_module("qmp")
except Exception as e:
self.logger.error("qemurunner: qmp.py missing, please ensure it's installed (%s)" % str(e))
return False
# Path relative to tmpdir used as cwd for qemu below to avoid unix socket path length issues
qmp_file = "." + next(tempfile._get_candidate_names())
qmp_param = ' -S -qmp unix:./%s,server,wait' % (qmp_file)
qmp_port = self.tmpdir + "/" + qmp_file
# Create a second socket connection for debugging use,
# note this will NOT cause qemu to block waiting for the connection
qmp_file2 = "." + next(tempfile._get_candidate_names())
qmp_param += ' -qmp unix:./%s,server,nowait' % (qmp_file2)
qmp_port2 = self.tmpdir + "/" + qmp_file2
self.logger.info("QMP Available for connection at %s" % (qmp_port2))
try:
if self.serial_ports >= 2:
self.threadsock, threadport = self.create_socket()
self.server_socket, self.serverport = self.create_socket()
except socket.error as msg:
self.logger.error("Failed to create listening socket: %s" % msg[1])
return False
bootparams = ' printk.time=1'
if extra_bootparams:
bootparams = bootparams + ' ' + extra_bootparams
# Ask QEMU to store the QEMU process PID in file, this way we don't have to parse running processes
# and analyze descendents in order to determine it.
if os.path.exists(self.qemu_pidfile):
os.remove(self.qemu_pidfile)
self.qemuparams = 'bootparams="{0}" qemuparams="-pidfile {1} {2}"'.format(bootparams, self.qemu_pidfile, qmp_param)
if qemuparams:
self.qemuparams = self.qemuparams[:-1] + " " + qemuparams + " " + '\"'
if self.serial_ports >= 2:
launch_cmd += ' tcpserial=%s:%s %s' % (threadport, self.serverport, self.qemuparams)
else:
launch_cmd += ' tcpserial=%s %s' % (self.serverport, self.qemuparams)
self.origchldhandler = signal.getsignal(signal.SIGCHLD)
signal.signal(signal.SIGCHLD, self.handleSIGCHLD)
self.logger.debug('launchcmd=%s'%(launch_cmd))
# FIXME: We pass in stdin=subprocess.PIPE here to work around stty
# blocking at the end of the runqemu script when using this within
# oe-selftest (this makes stty error out immediately). There ought
# to be a proper fix but this will suffice for now.
self.runqemu = subprocess.Popen(launch_cmd, shell=True, stdout=subprocess.PIPE, stderr=subprocess.STDOUT, stdin=subprocess.PIPE, preexec_fn=os.setpgrp, env=env, cwd=self.tmpdir)
output = self.runqemu.stdout
launch_time = time.time()
#
# We need the preexec_fn above so that all runqemu processes can easily be killed
# (by killing their process group). This presents a problem if this controlling
# process itself is killed however since those processes don't notice the death
# of the parent and merrily continue on.
#
# Rather than hack runqemu to deal with this, we add something here instead.
# Basically we fork off another process which holds an open pipe to the parent
# and also is setpgrp. If/when the pipe sees EOF from the parent dieing, it kills
# the process group. This is like pctrl's PDEATHSIG but for a process group
# rather than a single process.
#
r, w = os.pipe()
self.monitorpid = os.fork()
if self.monitorpid:
os.close(r)
self.monitorpipe = os.fdopen(w, "w")
else:
# child process
os.setpgrp()
os.close(w)
r = os.fdopen(r)
x = r.read()
os.killpg(os.getpgid(self.runqemu.pid), signal.SIGTERM)
os._exit(0)
self.logger.debug("runqemu started, pid is %s" % self.runqemu.pid)
self.logger.debug("waiting at most %s seconds for qemu pid (%s)" %
(self.runqemutime, time.strftime("%D %H:%M:%S")))
endtime = time.time() + self.runqemutime
while not self.is_alive() and time.time() < endtime:
if self.runqemu.poll():
if self.runqemu_exited:
self.logger.warning("runqemu during is_alive() test")
return False
if self.runqemu.returncode:
# No point waiting any longer
self.logger.warning('runqemu exited with code %d' % self.runqemu.returncode)
self._dump_host()
self.logger.warning("Output from runqemu:\n%s" % self.getOutput(output))
self.stop()
return False
time.sleep(0.5)
if self.runqemu_exited:
self.logger.warning("runqemu after timeout")
if self.runqemu.returncode:
self.logger.warning('runqemu exited with code %d' % self.runqemu.returncode)
if not self.is_alive():
self.logger.error("Qemu pid didn't appear in %s seconds (%s)" %
(self.runqemutime, time.strftime("%D %H:%M:%S")))
qemu_pid = None
if os.path.isfile(self.qemu_pidfile):
with open(self.qemu_pidfile, 'r') as f:
qemu_pid = f.read().strip()
self.logger.error("Status information, poll status: %s, pidfile exists: %s, pidfile contents %s, proc pid exists %s"
% (self.runqemu.poll(), os.path.isfile(self.qemu_pidfile), str(qemu_pid), os.path.exists("/proc/" + str(qemu_pid))))
# Dump all processes to help us to figure out what is going on...
ps = subprocess.Popen(['ps', 'axww', '-o', 'pid,ppid,pri,ni,command '], stdout=subprocess.PIPE).communicate()[0]
processes = ps.decode("utf-8")
self.logger.debug("Running processes:\n%s" % processes)
self._dump_host()
op = self.getOutput(output)
self.stop()
if op:
self.logger.error("Output from runqemu:\n%s" % op)
else:
self.logger.error("No output from runqemu.\n")
return False
# Create the client socket for the QEMU Monitor Control Socket
# This will allow us to read status from Qemu if the the process
# is still alive
self.logger.debug("QMP Initializing to %s" % (qmp_port))
# chdir dance for path length issues with unix sockets
origpath = os.getcwd()
try:
os.chdir(os.path.dirname(qmp_port))
try:
from qmp.legacy import QEMUMonitorProtocol
self.qmp = QEMUMonitorProtocol(os.path.basename(qmp_port))
except OSError as msg:
self.logger.warning("Failed to initialize qemu monitor socket: %s File: %s" % (msg, msg.filename))
return False
self.logger.debug("QMP Connecting to %s" % (qmp_port))
if not os.path.exists(qmp_port) and self.is_alive():
self.logger.debug("QMP Port does not exist waiting for it to be created")
endtime = time.time() + self.runqemutime
while not os.path.exists(qmp_port) and self.is_alive() and time.time() < endtime:
self.logger.info("QMP port does not exist yet!")
time.sleep(0.5)
if not os.path.exists(qmp_port) and self.is_alive():
self.logger.warning("QMP Port still does not exist but QEMU is alive")
return False
try:
self.qmp.connect()
connect_time = time.time()
self.logger.info("QMP connected to QEMU at %s and took %s seconds" %
(time.strftime("%D %H:%M:%S"),
time.time() - launch_time))
except OSError as msg:
self.logger.warning("Failed to connect qemu monitor socket: %s File: %s" % (msg, msg.filename))
return False
except qmp.legacy.QMPError as msg:
self.logger.warning("Failed to communicate with qemu monitor: %s" % (msg))
return False
finally:
os.chdir(origpath)
# We worry that mmap'd libraries may cause page faults which hang the qemu VM for periods
# causing failures. Before we "start" qemu, read through it's mapped files to try and
# ensure we don't hit page faults later
mapdir = "/proc/" + str(self.qemupid) + "/map_files/"
try:
for f in os.listdir(mapdir):
try:
linktarget = os.readlink(os.path.join(mapdir, f))
if not linktarget.startswith("/") or linktarget.startswith("/dev") or "deleted" in linktarget:
continue
with open(linktarget, "rb") as readf:
data = True
while data:
data = readf.read(4096)
except FileNotFoundError:
continue
# Centos7 doesn't allow us to read /map_files/
except PermissionError:
pass
# Release the qemu process to continue running
self.run_monitor('cont')
self.logger.info("QMP released QEMU at %s and took %s seconds from connect" %
(time.strftime("%D %H:%M:%S"),
time.time() - connect_time))
# We are alive: qemu is running
out = self.getOutput(output)
netconf = False # network configuration is not required by default
self.logger.debug("qemu started in %s seconds - qemu procces pid is %s (%s)" %
(time.time() - (endtime - self.runqemutime),
self.qemupid, time.strftime("%D %H:%M:%S")))
cmdline = ''
if get_ip:
with open('/proc/%s/cmdline' % self.qemupid) as p:
cmdline = p.read()
# It is needed to sanitize the data received
# because is possible to have control characters
cmdline = re_control_char.sub(' ', cmdline)
try:
if self.use_slirp:
tcp_ports = cmdline.split("hostfwd=tcp:")[1]
ip, tcp_ports = tcp_ports.split(":")[:2]
host_port = tcp_ports[:tcp_ports.find('-')]
self.ip = "%s:%s" % (ip, host_port)
else:
ips = re.findall(r"((?:[0-9]{1,3}\.){3}[0-9]{1,3})", cmdline.split("ip=")[1])
self.ip = ips[0]
self.server_ip = ips[1]
self.logger.debug("qemu cmdline used:\n{}".format(cmdline))
except (IndexError, ValueError):
# Try to get network configuration from runqemu output
match = re.match(r'.*Network configuration: (?:ip=)*([0-9.]+)::([0-9.]+):([0-9.]+).*',
out, re.MULTILINE|re.DOTALL)
if match:
self.ip, self.server_ip, self.netmask = match.groups()
# network configuration is required as we couldn't get it
# from the runqemu command line, so qemu doesn't run kernel
# and guest networking is not configured
netconf = True
else:
self.logger.error("Couldn't get ip from qemu command line and runqemu output! "
"Here is the qemu command line used:\n%s\n"
"and output from runqemu:\n%s" % (cmdline, out))
self._dump_host()
self.stop()
return False
self.logger.debug("Target IP: %s" % self.ip)
self.logger.debug("Server IP: %s" % self.server_ip)
if self.serial_ports >= 2:
self.thread = LoggingThread(self.log, self.threadsock, self.logger)
self.thread.start()
if not self.thread.connection_established.wait(self.boottime):
self.logger.error("Didn't receive a console connection from qemu. "
"Here is the qemu command line used:\n%s\nand "
"output from runqemu:\n%s" % (cmdline, out))
self.stop_thread()
return False
self.logger.debug("Output from runqemu:\n%s", out)
self.logger.debug("Waiting at most %d seconds for login banner (%s)" %
(self.boottime, time.strftime("%D %H:%M:%S")))
endtime = time.time() + self.boottime
socklist = [self.server_socket]
reachedlogin = False
stopread = False
qemusock = None
bootlog = b''
data = b''
while time.time() < endtime and not stopread:
try:
sread, swrite, serror = select.select(socklist, [], [], 5)
except InterruptedError:
continue
for sock in sread:
if sock is self.server_socket:
qemusock, addr = self.server_socket.accept()
qemusock.setblocking(0)
socklist.append(qemusock)
socklist.remove(self.server_socket)
self.logger.debug("Connection from %s:%s" % addr)
else:
data = data + sock.recv(1024)
if data:
bootlog += data
if self.serial_ports < 2:
# this socket has mixed console/kernel data, log it to logfile
self.log(data)
data = b''
decodedlog = self.decode_qemulog(bootlog)
if self.boot_patterns['search_reached_prompt'] in decodedlog:
self.server_socket = qemusock
stopread = True
reachedlogin = True
self.logger.debug("Reached login banner in %s seconds (%s, %s)" %
(time.time() - (endtime - self.boottime),
time.strftime("%D %H:%M:%S"), time.time()))
else:
# no need to check if reachedlogin unless we support multiple connections
self.logger.debug("QEMU socket disconnected before login banner reached. (%s)" %
time.strftime("%D %H:%M:%S"))
socklist.remove(sock)
sock.close()
stopread = True
if not reachedlogin:
if time.time() >= endtime:
self.logger.warning("Target didn't reach login banner in %d seconds (%s)" %
(self.boottime, time.strftime("%D %H:%M:%S")))
tail = lambda l: "\n".join(l.splitlines()[-25:])
bootlog = self.decode_qemulog(bootlog)
# in case bootlog is empty, use tail qemu log store at self.msg
lines = tail(bootlog if bootlog else self.msg)
self.logger.warning("Last 25 lines of text (%d):\n%s" % (len(bootlog), lines))
self.logger.warning("Check full boot log: %s" % self.logfile)
self._dump_host()
self.stop()
return False
# If we are not able to login the tests can continue
try:
(status, output) = self.run_serial(self.boot_patterns['send_login_user'], raw=True, timeout=120)
if re.search(self.boot_patterns['search_login_succeeded'], output):
self.logged = True
self.logger.debug("Logged as root in serial console")
if netconf:
# configure guest networking
cmd = "ifconfig eth0 %s netmask %s up\n" % (self.ip, self.netmask)
output = self.run_serial(cmd, raw=True)[1]
if re.search(r"root@[a-zA-Z0-9\-]+:~#", output):
self.logger.debug("configured ip address %s", self.ip)
else:
self.logger.debug("Couldn't configure guest networking")
else:
self.logger.warning("Couldn't login into serial console"
" as root using blank password")
self.logger.warning("The output:\n%s" % output)
except:
self.logger.warning("Serial console failed while trying to login")
return True
def stop(self):
if hasattr(self, "origchldhandler"):
signal.signal(signal.SIGCHLD, self.origchldhandler)
self.stop_thread()
self.stop_qemu_system()
if self.runqemu:
if hasattr(self, "monitorpid"):
os.kill(self.monitorpid, signal.SIGKILL)
self.logger.debug("Sending SIGTERM to runqemu")
try:
os.killpg(os.getpgid(self.runqemu.pid), signal.SIGTERM)
except OSError as e:
if e.errno != errno.ESRCH:
raise
endtime = time.time() + self.runqemutime
while self.runqemu.poll() is None and time.time() < endtime:
time.sleep(1)
if self.runqemu.poll() is None:
self.logger.debug("Sending SIGKILL to runqemu")
os.killpg(os.getpgid(self.runqemu.pid), signal.SIGKILL)
if not self.runqemu.stdout.closed:
self.logger.info("Output from runqemu:\n%s" % self.getOutput(self.runqemu.stdout))
self.runqemu.stdin.close()
self.runqemu.stdout.close()
self.runqemu_exited = True
if hasattr(self, 'qmp') and self.qmp:
self.qmp.close()
self.qmp = None
if hasattr(self, 'server_socket') and self.server_socket:
self.server_socket.close()
self.server_socket = None
if hasattr(self, 'threadsock') and self.threadsock:
self.threadsock.close()
self.threadsock = None
self.qemupid = None
self.ip = None
if os.path.exists(self.qemu_pidfile):
try:
os.remove(self.qemu_pidfile)
except FileNotFoundError as e:
# We raced, ignore
pass
if self.monitorpipe:
self.monitorpipe.close()
def stop_qemu_system(self):
if self.qemupid:
try:
# qemu-system behaves well and a SIGTERM is enough
os.kill(self.qemupid, signal.SIGTERM)
except ProcessLookupError as e:
self.logger.warning('qemu-system ended unexpectedly')
def stop_thread(self):
if self.thread and self.thread.is_alive():
self.thread.stop()
self.thread.join()
def allowexit(self):
self.canexit = True
if self.thread:
self.thread.allowexit()
def restart(self, qemuparams = None):
self.logger.warning("Restarting qemu process")
if self.runqemu.poll() is None:
self.stop()
if self.start(qemuparams):
return True
return False
def is_alive(self):
if not self.runqemu or self.runqemu.poll() is not None or self.runqemu_exited:
return False
if os.path.isfile(self.qemu_pidfile):
# when handling pidfile, qemu creates the file, stat it, lock it and then write to it
# so it's possible that the file has been created but the content is empty
pidfile_timeout = time.time() + 3
while time.time() < pidfile_timeout:
with open(self.qemu_pidfile, 'r') as f:
qemu_pid = f.read().strip()
# file created but not yet written contents
if not qemu_pid:
time.sleep(0.5)
continue
else:
if os.path.exists("/proc/" + qemu_pid):
self.qemupid = int(qemu_pid)
return True
return False
def run_monitor(self, command, args=None, timeout=60):
if hasattr(self, 'qmp') and self.qmp:
if args is not None:
return self.qmp.cmd(command, args)
else:
return self.qmp.cmd(command)
def run_serial(self, command, raw=False, timeout=60):
# Returns (status, output) where status is 1 on success and 0 on error
# We assume target system have echo to get command status
if not raw:
command = "%s; echo $?\n" % command
data = ''
status = 0
self.server_socket.sendall(command.encode('utf-8'))
start = time.time()
end = start + timeout
while True:
now = time.time()
if now >= end:
data += "<<< run_serial(): command timed out after %d seconds without output >>>\r\n\r\n" % timeout
break
try:
sread, _, _ = select.select([self.server_socket],[],[], end - now)
except InterruptedError:
continue
if sread:
answer = self.server_socket.recv(1024)
if answer:
data += answer.decode('utf-8')
# Search the prompt to stop
if re.search(self.boot_patterns['search_cmd_finished'], data):
break
else:
if self.canexit:
return (1, "")
raise Exception("No data on serial console socket, connection closed?")
if data:
if raw:
status = 1
else:
# Remove first line (command line) and last line (prompt)
data = data[data.find('$?\r\n')+4:data.rfind('\r\n')]
index = data.rfind('\r\n')
if index == -1:
status_cmd = data
data = ""
else:
status_cmd = data[index+2:]
data = data[:index]
if (status_cmd == "0"):
status = 1
return (status, str(data))
def _dump_host(self):
self.host_dumper.create_dir("qemu")
self.logger.warning("Qemu ended unexpectedly, dump data from host"
" is in %s" % self.host_dumper.dump_dir)
self.host_dumper.dump_host()
# This class is for reading data from a socket and passing it to logfunc
# to be processed. It's completely event driven and has a straightforward
# event loop. The mechanism for stopping the thread is a simple pipe which
# will wake up the poll and allow for tearing everything down.
class LoggingThread(threading.Thread):
def __init__(self, logfunc, sock, logger):
self.connection_established = threading.Event()
self.serversock = sock
self.logfunc = logfunc
self.logger = logger
self.readsock = None
self.running = False
self.canexit = False
self.errorevents = select.POLLERR | select.POLLHUP | select.POLLNVAL
self.readevents = select.POLLIN | select.POLLPRI
threading.Thread.__init__(self, target=self.threadtarget)
def threadtarget(self):
try:
self.eventloop()
finally:
self.teardown()
def run(self):
self.logger.debug("Starting logging thread")
self.readpipe, self.writepipe = os.pipe()
threading.Thread.run(self)
def stop(self):
self.logger.debug("Stopping logging thread")
if self.running:
os.write(self.writepipe, bytes("stop", "utf-8"))
def teardown(self):
self.logger.debug("Tearing down logging thread")
self.close_socket(self.serversock)
if self.readsock is not None:
self.close_socket(self.readsock)
self.close_ignore_error(self.readpipe)
self.close_ignore_error(self.writepipe)
self.running = False
def allowexit(self):
self.canexit = True
def eventloop(self):
poll = select.poll()
event_read_mask = self.errorevents | self.readevents
poll.register(self.serversock.fileno())
poll.register(self.readpipe, event_read_mask)
breakout = False
self.running = True
self.logger.debug("Starting thread event loop")
while not breakout:
events = poll.poll()
for event in events:
# An error occurred, bail out
if event[1] & self.errorevents:
raise Exception(self.stringify_event(event[1]))
# Event to stop the thread
if self.readpipe == event[0]:
self.logger.debug("Stop event received")
breakout = True
break
# A connection request was received
elif self.serversock.fileno() == event[0]:
self.logger.debug("Connection request received")
self.readsock, _ = self.serversock.accept()
self.readsock.setblocking(0)
poll.unregister(self.serversock.fileno())
poll.register(self.readsock.fileno(), event_read_mask)
self.logger.debug("Setting connection established event")
self.connection_established.set()
# Actual data to be logged
elif self.readsock.fileno() == event[0]:
data = self.recv(1024)
self.logfunc(data)
# Since the socket is non-blocking make sure to honor EAGAIN
# and EWOULDBLOCK.
def recv(self, count):
try:
data = self.readsock.recv(count)
except socket.error as e:
if e.errno == errno.EAGAIN or e.errno == errno.EWOULDBLOCK:
return b''
else:
raise
if data is None:
raise Exception("No data on read ready socket")
elif not data:
# This actually means an orderly shutdown
# happened. But for this code it counts as an
# error since the connection shouldn't go away
# until qemu exits.
if not self.canexit:
raise Exception("Console connection closed unexpectedly")
return b''
return data
def stringify_event(self, event):
val = ''
if select.POLLERR == event:
val = 'POLLER'
elif select.POLLHUP == event:
val = 'POLLHUP'
elif select.POLLNVAL == event:
val = 'POLLNVAL'
return val
def close_socket(self, sock):
sock.shutdown(socket.SHUT_RDWR)
sock.close()
def close_ignore_error(self, fd):
try:
os.close(fd)
except OSError:
pass