# -*- python -*-
'''
xpybar – xmobar replacement written in python
Copyright © 2014, 2015 Mattias Andrée (maandree@member.fsf.org)
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 os
from util import *
from plugins.linereader import LineReader
class Ping:
'''
Network connectivity monitor using ICMP echos
@variable monitors:dict<str, list<Ping.create_monitor.PingMonitor>>
Map from network interface to list of network monitors
connected against the server specified by the corresponding
element in `targets` of `__init__`
'''
DEFAULT_GATEWAY = ...
'''
Selects the default gateway's IP address
'''
UNITS = { 'ns' : 0.000001, 'us' : 0.001, 'µs' : 0.001, 'ms' : 1.0, 's' : 1000.0 }
def __init__(self, targets = None, interval = 5, arguments = None, buffer_size = 8):
'''
Constructor
@param targets:dict<str, itr<str|...>> Map from network interfaces to servers to ping
@param interval:float The pinging interval, in seconds
@param arguments:itr<str>? Extra arguments for the `ping` command
'''
if targets is None:
targets = Ping.get_nics()
gateways = Ping.get_default_gateways()
args = ['ping', '-i', str(interval)] + (arguments if arguments is not None else [])
def get(nic, target):
if target == Ping.DEFAULT_GATEWAY:
target = None if nic not in gateways else gateways[nic]
if target is None:
return None
command = args + ['-I', nic, target]
return Ping.create_monitor(command, buffer_size, interval)
self.monitors = dict((nic, [get(nic, t) for t in targets[nic]]) for nic in targets.keys())
@staticmethod
def get_nics(server = ...):
'''
List all network interfaces with a default gateway
and map them to `server`
@return :dict<str, [`server`]> Dictionary of network interfaces mapped to `server`
'''
data = spawn_read('ip', 'route').split('\n')
def get(fields):
device = fields[fields.index('dev') + 1]
return (device, [server])
return dict(get(line.split(' ')) for line in data if line.startswith('default via '))
@staticmethod
def get_default_gateways():
'''
All network interfaces with a default gateway mapped to their default gateways
@return :dict<str, str> Map from network interfaces to their default gateways
'''
data = spawn_read('ip', 'route').split('\n')
def get(fields):
gateway = fields[2]
device = fields[fields.index('dev') + 1]
return (device, gateway)
return dict(get(line.split(' ')) for line in data if line.startswith('default via '))
@staticmethod
def create_monitor(command, buffer_size, interval):
import time
class PingMonitor:
def __init__(self):
self.latency_buffer = [None] * buffer_size
self.semaphore = threading.Semaphore()
self.last_read = time.monotonic()
self.last_icmp_seq = 0
def start(self):
with LineReader(spawn(*command)) as reader:
reader.next()
while True:
line = reader.next()
self.semaphore.acquire()
try:
line = line.replace('=', ' ').split(' ')
icmp_seq = int(line[line.index('icmp_seq') + 1])
ping_time = float(line[line.index('time') + 1])
ping_time *= Ping.UNITS[line[line.index('time') + 2]]
dropped_pkgs = icmp_seq - self.last_icmp_seq - 1
dropped_pkgs = [None] * dropped_pkgs
self.last_icmp_seq = icmp_seq
self.latency_buffer[:] = ([ping_time] + dropped_pkgs + self.latency_buffer)[:buffer_size]
self.last_read = time.monotonic()
except:
pass
finally:
self.semaphore.release()
def get_latency(self, acquired = False):
'''
Get the average responses-time
@return :list<float?> For index `n` (limited to `buffer_size` inclusively):
the average response time for the latest `n - d` received
pongs, where `d` is not number of dropped packages of the
latest `n` sent pings. If the average response time cannot
be calculated (if all packages have been dropped), the
value will be `None`. Note that the value at index 0 will
always be `None`, because index 0 means no packages.
'''
if not acquired:
self.semaphore.acquire()
try:
rc = [None]
cursum = 0
samples = 0
for i in range(buffer_size):
if self.latency_buffer[i] is not None:
cursum += self.latency_buffer[i]
samples += 1
rc.append(None if samples == 0 else cursum / samples)
return rc
finally:
if not acquired:
self.semaphore.release()
def dropped(self, acquired = False):
'''
Estimate how many echos have been dropped since the last pong
@return :int The estimated number of dropped packages
'''
if not acquired:
self.semaphore.acquire()
try:
return (time.monotonic() - self.last_read) // interval
finally:
if not acquired:
self.semaphore.release()
def dropped_time(self, acquired = False):
'''
Estimate for how long packages have been dropping
@return :float The estimated time packages have been dropping, in seconds
'''
if not acquired:
self.semaphore.acquire()
try:
time_diff = time.monotonic() - self.last_read
return 0 if time_diff < interval else time_diff
finally:
if not acquired:
self.semaphore.release()
monitor = PingMonitor()
async(monitor.start)
return monitor
