Files
linux/tools/testing/selftests/net/lib/py/utils.py
Jakub Kicinski 8b8fe28015 selftests: drv-net: try to check if port is in use
We use random ports for communication. As Willem predicted
this leads to occasional failures. Try to check if port is
already in use by opening a socket and binding to that port.

Reviewed-by: Przemek Kitszel <przemyslaw.kitszel@intel.com>
Reviewed-by: Petr Machata <petrm@nvidia.com>
Reviewed-by: Willem de Bruijn <willemb@google.com>
Link: https://patch.msgid.link/20240626012456.2326192-2-kuba@kernel.org
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-06-26 19:06:03 -07:00

114 lines
3.4 KiB
Python

# SPDX-License-Identifier: GPL-2.0
import errno
import json as _json
import random
import re
import socket
import subprocess
import time
class cmd:
def __init__(self, comm, shell=True, fail=True, ns=None, background=False, host=None, timeout=5):
if ns:
comm = f'ip netns exec {ns} ' + comm
self.stdout = None
self.stderr = None
self.ret = None
self.comm = comm
if host:
self.proc = host.cmd(comm)
else:
self.proc = subprocess.Popen(comm, shell=shell, stdout=subprocess.PIPE,
stderr=subprocess.PIPE)
if not background:
self.process(terminate=False, fail=fail, timeout=timeout)
def process(self, terminate=True, fail=None, timeout=5):
if fail is None:
fail = not terminate
if terminate:
self.proc.terminate()
stdout, stderr = self.proc.communicate(timeout)
self.stdout = stdout.decode("utf-8")
self.stderr = stderr.decode("utf-8")
self.proc.stdout.close()
self.proc.stderr.close()
self.ret = self.proc.returncode
if self.proc.returncode != 0 and fail:
if len(stderr) > 0 and stderr[-1] == "\n":
stderr = stderr[:-1]
raise Exception("Command failed: %s\nSTDOUT: %s\nSTDERR: %s" %
(self.proc.args, stdout, stderr))
class bkg(cmd):
def __init__(self, comm, shell=True, fail=None, ns=None, host=None,
exit_wait=False):
super().__init__(comm, background=True,
shell=shell, fail=fail, ns=ns, host=host)
self.terminate = not exit_wait
self.check_fail = fail
def __enter__(self):
return self
def __exit__(self, ex_type, ex_value, ex_tb):
return self.process(terminate=self.terminate, fail=self.check_fail)
def tool(name, args, json=None, ns=None, host=None):
cmd_str = name + ' '
if json:
cmd_str += '--json '
cmd_str += args
cmd_obj = cmd(cmd_str, ns=ns, host=host)
if json:
return _json.loads(cmd_obj.stdout)
return cmd_obj
def ip(args, json=None, ns=None, host=None):
if ns:
args = f'-netns {ns} ' + args
return tool('ip', args, json=json, host=host)
def rand_port():
"""
Get a random unprivileged port, try to make sure it's not already used.
"""
for _ in range(1000):
port = random.randint(10000, 65535)
try:
with socket.socket(socket.AF_INET6, socket.SOCK_STREAM) as s:
s.bind(("", port))
return port
except OSError as e:
if e.errno != errno.EADDRINUSE:
raise
raise Exception("Can't find any free unprivileged port")
def wait_port_listen(port, proto="tcp", ns=None, host=None, sleep=0.005, deadline=5):
end = time.monotonic() + deadline
pattern = f":{port:04X} .* "
if proto == "tcp": # for tcp protocol additionally check the socket state
pattern += "0A"
pattern = re.compile(pattern)
while True:
data = cmd(f'cat /proc/net/{proto}*', ns=ns, host=host, shell=True).stdout
for row in data.split("\n"):
if pattern.search(row):
return
if time.monotonic() > end:
raise Exception("Waiting for port listen timed out")
time.sleep(sleep)