def single_instance_unix(name: str) -> bool:
import socket
for path in unix_socket_paths(name):
socket_path = path.rpartition('.')[0] + '.sock'
fd = os.open(path,
os.O_CREAT | os.O_WRONLY | os.O_TRUNC | os.O_CLOEXEC)
try:
fcntl.lockf(fd, fcntl.LOCK_EX | fcntl.LOCK_NB)
except OSError as err:
if err.errno in (errno.EAGAIN, errno.EACCES):
# Client
s = socket.socket(family=socket.AF_UNIX)
s.connect(socket_path)
single_instance.socket = s
return False
raise
s = socket.socket(family=socket.AF_UNIX)
try:
s.bind(socket_path)
except OSError as err:
if err.errno in (errno.EADDRINUSE, errno.EEXIST):
os.unlink(socket_path)
s.bind(socket_path)
else:
raise
single_instance.socket = s # prevent garbage collection from closing the socket
atexit.register(remove_socket_file, s, socket_path)
s.listen()
s.set_inheritable(False)
return True
return False
def __call__(self, group_id: Optional[str] = None) -> bool:
import socket
name = '{}-ipc-{}'.format(appname, os.geteuid())
if group_id:
name += '-{}'.format(group_id)
s = socket.socket(family=socket.AF_UNIX)
# First try with abstract UDS
addr = '\0' + name
try:
s.bind(addr)
except OSError as err:
if err.errno == errno.ENOENT:
return single_instance_unix(name)
if err.errno == errno.EADDRINUSE:
s.connect(addr)
self.socket = s
return False
raise
s.listen()
self.socket = s # prevent garbage collection from closing the socket
s.set_inheritable(False)
atexit.register(remove_socket_file, s)
return True
