def _try_lock(self, pid):
fd = os.open(self.target, os.O_CREAT | os.O_RDWR, 0o644)
try:
try:
fcntl.flock(fd, fcntl.LOCK_EX | fcntl.LOCK_NB)
except OSError as e:
if e.errno == errno.EWOULDBLOCK:
return -1
raise
old_pid = os.read(fd, 20)
if len(old_pid) == 0:
# empty file, write our pid
os.write(fd, str(pid).encode('utf-8'))
return pid
try:
old_pid = int(old_pid)
except ValueError:
msg = _('Malformed lock file found: %s.\n'
'Ensure no other dnf/yum process is running and '
'remove the lock file manually or run '
'systemd-tmpfiles --remove dnf.conf.') % (self.target)
raise LockError(msg)
if old_pid == pid:
# already locked by this process
return pid
if not os.access('/proc/%d/stat' % old_pid, os.F_OK):
# locked by a dead process, write our pid
os.lseek(fd, 0, os.SEEK_SET)
os.ftruncate(fd, 0)
os.write(fd, str(pid).encode('utf-8'))
return pid
try:
with open('/proc/%d/status' % old_pid) as f:
if not re.findall(r'Name:(.*)(dnf|yum)', f.read(), re.I):
os.write(fd, str(pid).encode('utf-8'))
return pid
except OSError as e:
msg = _('Malformed lock file found: %s.\n'
'But pid in lock file is invalid '
'Ensure no other dnf/yum process is running and '
'remove the lock file manually.') % (self.target)
raise LockError(msg)
return old_pid
finally:
os.close(fd)
def _try_read_lock(self):
try:
with open(self.target, 'r') as f:
return int(f.readline())
except IOError:
return -1
except ValueError:
time.sleep(2)
try:
with open(self.target, 'r') as f:
return int(f.readline())
except IOError:
return -1
except ValueError:
msg = _('Malformed lock file found: %s.\n'
'Ensure no other dnf process is running and '
'remove the lock file manually or run '
'systemd-tmpfiles --remove dnf.conf.' % (self.target))
raise LockError(msg)