# Copyright 2014 The Chromium OS Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
import ConfigParser
import io
import collections
import logging
import shlex
import time
from autotest_lib.client.bin import utils
from autotest_lib.client.common_lib import error
from autotest_lib.client.common_lib.cros import dbus_send
BUS_NAME = 'org.freedesktop.Avahi'
INTERFACE_SERVER = 'org.freedesktop.Avahi.Server'
ServiceRecord = collections.namedtuple(
'ServiceRecord',
['interface', 'protocol', 'name', 'record_type', 'domain',
'hostname', 'address', 'port', 'txt'])
def avahi_config(options, src_file='/etc/avahi/avahi-daemon.conf', host=None):
"""Creates a temporary avahi-daemon.conf file with the specified changes.
Avahi daemon uses a text configuration file with sections and values
assigned to options on that section. This function creates a new config
file based on the one provided and a set of changes. The changes are
specified as triples of section, option and value that override the existing
options on the config file. If a value of None is specified for any triplet,
the corresponding option will be removed from the file.
@param options: A list of triplets of the form (section, option, value).
@param src_file: The default config file to use as a base for the changes.
@param host: An optional host object if running against a remote host.
@return: The filename of a temporary file with the new configuration file.
"""
run = utils.run if host is None else host.run
existing_config = run('cat %s 2> /dev/null' % src_file).stdout
conf = ConfigParser.SafeConfigParser()
conf.readfp(io.BytesIO(existing_config))
for section, option, value in options:
if not conf.has_section(section):
conf.add_section(section)
if value is None:
conf.remove_option(section, option)
else:
conf.set(section, option, value)
tmp_conf_file = run('mktemp -t avahi-conf.XXXX').stdout.strip()
lines = []
for section in conf.sections():
lines.append('[%s]' % section)
for option in conf.options(section):
lines.append('%s=%s' % (option, conf.get(section, option)))
run('cat <<EOF >%s\n%s\nEOF\n' % (tmp_conf_file, '\n'.join(lines)))
return tmp_conf_file
def avahi_ping(host=None):
"""Returns True when the avahi-deamon's DBus interface is ready.
After your launch avahi-daemon, there is a short period of time where the
daemon is running but the DBus interface isn't ready yet. This functions
blocks for a few seconds waiting for a ping response from the DBus API
and returns wether it got a response.
@param host: An optional host object if running against a remote host.
@return boolean: True if Avahi is up and in a stable state.
"""
result = dbus_send.dbus_send(BUS_NAME, INTERFACE_SERVER, '/', 'GetState',
host=host, timeout_seconds=2,
tolerate_failures=True)
# AVAHI_ENTRY_GROUP_ESTABLISHED == 2
return result is not None and result.response == 2
def avahi_start(config_file=None, host=None):
"""Start avahi-daemon with the provided config file.
This function waits until the avahi-daemon is ready listening on the DBus
interface. If avahi fails to be ready after 10 seconds, an error is raised.
@param config_file: The filename of the avahi-daemon config file or None to
use the default.
@param host: An optional host object if running against a remote host.
"""
run = utils.run if host is None else host.run
env = ''
if config_file is not None:
env = ' AVAHI_DAEMON_CONF="%s"' % config_file
run('start avahi %s' % env, ignore_status=False)
# Wait until avahi is ready.
deadline = time.time() + 10.
while time.time() < deadline:
if avahi_ping(host=host):
return
time.sleep(0.1)
raise error.TestError('avahi-daemon is not ready after 10s running.')
def avahi_stop(ignore_status=False, host=None):
"""Stop the avahi daemon.
@param ignore_status: True to ignore failures while stopping avahi.
@param host: An optional host object if running against a remote host.
"""
run = utils.run if host is None else host.run
run('stop avahi', ignore_status=ignore_status)
def avahi_start_on_iface(iface, host=None):
"""Starts avahi daemon listening only on the provided interface.
@param iface: A string with the interface name.
@param host: An optional host object if running against a remote host.
"""
run = utils.run if host is None else host.run
opts = [('server', 'allow-interfaces', iface),
('server', 'deny-interfaces', None)]
conf = avahi_config(opts, host=host)
avahi_start(config_file=conf, host=host)
run('rm %s' % conf)
def avahi_get_hostname(host=None):
"""Get the lan-unique hostname of the the device.
@param host: An optional host object if running against a remote host.
@return string: the lan-unique hostname of the DUT.
"""
result = dbus_send.dbus_send(
BUS_NAME, INTERFACE_SERVER, '/', 'GetHostName',
host=host, timeout_seconds=2, tolerate_failures=True)
return None if result is None else result.response
def avahi_get_domain_name(host=None):
"""Get the current domain name being used by Avahi.
@param host: An optional host object if running against a remote host.
@return string: the current domain name being used by Avahi.
"""
result = dbus_send.dbus_send(
BUS_NAME, INTERFACE_SERVER, '/', 'GetDomainName',
host=host, timeout_seconds=2, tolerate_failures=True)
return None if result is None else result.response
def avahi_browse(host=None, ignore_local=True):
"""Browse mDNS service records with avahi-browse.
Some example avahi-browse output (lines are wrapped for readability):
localhost ~ # avahi-browse -tarlp
+;eth1;IPv4;E58E8561-3BCA-4910-ABC7-BD8779D7D761;_serbus._tcp;local
+;eth1;IPv4;E58E8561-3BCA-4910-ABC7-BD8779D7D761;_privet._tcp;local
=;eth1;IPv4;E58E8561-3BCA-4910-ABC7-BD8779D7D761;_serbus._tcp;local;\
9bcd92bbc1f91f2ee9c9b2e754cfd22e.local;172.22.23.237;0;\
"ver=1.0" "services=privet" "id=11FB0AD6-6C87-433E-8ACB-0C68EE78CDBD"
=;eth1;IPv4;E58E8561-3BCA-4910-ABC7-BD8779D7D761;_privet._tcp;local;\
9bcd92bbc1f91f2ee9c9b2e754cfd22e.local;172.22.23.237;8080;\
"ty=Unnamed Device" "txtvers=3" "services=_camera" "model_id=///" \
"id=FEE9B312-1F2B-4B9B-813C-8482FA75E0DB" "flags=AB" "class=BB"
@param host: An optional host object if running against a remote host.
@param ignore_local: boolean True to ignore local service records.
@return list of ServiceRecord objects parsed from output.
"""
run = utils.run if host is None else host.run
flags = ['--terminate', # Terminate after looking for a short time.
'--all', # Show all services, regardless of type.
'--resolve', # Resolve the services discovered.
'--parsable', # Print service records in a parsable format.
]
if ignore_local:
flags.append('--ignore-local')
result = run('avahi-browse %s' % ' '.join(flags))
records = []
for line in result.stdout.strip().splitlines():
parts = line.split(';')
if parts[0] == '+':
# Skip it, just parse the resolved record.
continue
# Do minimal parsing of the TXT record.
parts[-1] = shlex.split(parts[-1])
records.append(ServiceRecord(*parts[1:]))
logging.debug('Found %r', records[-1])
return records