class _LockProcess(AbstractPollTask):
"""
This uses the portage.locks module to acquire a lock asynchronously,
using a subprocess. After the lock is acquired, the process
writes to a pipe in order to notify a poll loop running in the main
process. The unlock() method notifies the subprocess to release the
lock and exit.
"""
__slots__ = ('path',) + \
('_acquired', '_kill_test', '_proc', '_files', '_unlock_future')
def _start(self):
in_pr, in_pw = os.pipe()
out_pr, out_pw = os.pipe()
self._files = {}
self._files['pipe_in'] = in_pr
self._files['pipe_out'] = out_pw
fcntl.fcntl(in_pr, fcntl.F_SETFL,
fcntl.fcntl(in_pr, fcntl.F_GETFL) | os.O_NONBLOCK)
# FD_CLOEXEC is enabled by default in Python >=3.4.
if sys.hexversion < 0x3040000:
try:
fcntl.FD_CLOEXEC
except AttributeError:
pass
else:
fcntl.fcntl(
in_pr, fcntl.F_SETFD,
fcntl.fcntl(in_pr, fcntl.F_GETFD) | fcntl.FD_CLOEXEC)
self.scheduler.add_reader(in_pr, self._output_handler)
self._registered = True
self._proc = SpawnProcess(args=[
portage._python_interpreter,
os.path.join(portage._bin_path, 'lock-helper.py'), self.path
],
env=dict(os.environ,
PORTAGE_PYM_PATH=portage._pym_path),
fd_pipes={
0: out_pr,
1: in_pw,
2: sys.__stderr__.fileno()
},
scheduler=self.scheduler)
self._proc.addExitListener(self._proc_exit)
self._proc.start()
os.close(out_pr)
os.close(in_pw)
def _proc_exit(self, proc):
if self._files is not None:
# Close pipe_out if it's still open, since it's useless
# after the process has exited. This helps to avoid
# "ResourceWarning: unclosed file" since Python 3.2.
try:
pipe_out = self._files.pop('pipe_out')
except KeyError:
pass
else:
os.close(pipe_out)
if proc.returncode != os.EX_OK:
# Typically, this will happen due to the
# process being killed by a signal.
if not self._acquired:
# If the lock hasn't been aquired yet, the
# caller can check the returncode and handle
# this failure appropriately.
if not (self.cancelled or self._kill_test):
writemsg_level("_LockProcess: %s\n" % \
_("failed to acquire lock on '%s'") % (self.path,),
level=logging.ERROR, noiselevel=-1)
self._unregister()
self.returncode = proc.returncode
self._async_wait()
return
if not self.cancelled and \
self._unlock_future is None:
# We don't want lost locks going unnoticed, so it's
# only safe to ignore if either the cancel() or
# unlock() methods have been previously called.
raise AssertionError("lock process failed with returncode %s" \
% (proc.returncode,))
if self._unlock_future is not None:
self._unlock_future.set_result(None)
def _cancel(self):
if self._proc is not None:
self._proc.cancel()
def _poll(self):
if self._proc is not None:
self._proc.poll()
return self.returncode
def _output_handler(self):
buf = self._read_buf(self._files['pipe_in'])
if buf:
self._acquired = True
self._unregister()
self.returncode = os.EX_OK
self._async_wait()
return True
def _unregister(self):
self._registered = False
if self._files is not None:
try:
pipe_in = self._files.pop('pipe_in')
except KeyError:
pass
else:
self.scheduler.remove_reader(pipe_in)
os.close(pipe_in)
def _unlock(self):
if self._proc is None:
raise AssertionError('not locked')
if not self._acquired:
raise AssertionError('lock not acquired yet')
if self.returncode != os.EX_OK:
raise AssertionError("lock process failed with returncode %s" \
% (self.returncode,))
if self._unlock_future is not None:
raise AssertionError("already unlocked")
self._unlock_future = self.scheduler.create_future()
os.write(self._files['pipe_out'], b'\0')
os.close(self._files['pipe_out'])
self._files = None
def async_unlock(self):
"""
Release the lock asynchronously. Release notification is available
via the add_done_callback method of the returned Future instance.
@returns: Future, result is None
"""
self._unlock()
return self._unlock_future
class _LockProcess(AbstractPollTask):
"""
This uses the portage.locks module to acquire a lock asynchronously,
using a subprocess. After the lock is acquired, the process
writes to a pipe in order to notify a poll loop running in the main
process. The unlock() method notifies the subprocess to release the
lock and exit.
"""
__slots__ = ('path',) + \
('_acquired', '_kill_test', '_proc', '_files', '_reg_id', '_unlocked')
def _start(self):
in_pr, in_pw = os.pipe()
out_pr, out_pw = os.pipe()
self._files = {}
self._files['pipe_in'] = in_pr
self._files['pipe_out'] = out_pw
fcntl.fcntl(in_pr, fcntl.F_SETFL,
fcntl.fcntl(in_pr, fcntl.F_GETFL) | os.O_NONBLOCK)
self._reg_id = self.scheduler.io_add_watch(in_pr,
self.scheduler.IO_IN, self._output_handler)
self._registered = True
self._proc = SpawnProcess(
args=[portage._python_interpreter,
os.path.join(portage._bin_path, 'lock-helper.py'), self.path],
env=dict(os.environ, PORTAGE_PYM_PATH=portage._pym_path),
fd_pipes={0:out_pr, 1:in_pw, 2:sys.stderr.fileno()},
scheduler=self.scheduler)
self._proc.addExitListener(self._proc_exit)
self._proc.start()
os.close(out_pr)
os.close(in_pw)
def _proc_exit(self, proc):
if self._files is not None:
# Close pipe_out if it's still open, since it's useless
# after the process has exited. This helps to avoid
# "ResourceWarning: unclosed file" since Python 3.2.
try:
pipe_out = self._files.pop('pipe_out')
except KeyError:
pass
else:
os.close(pipe_out)
if proc.returncode != os.EX_OK:
# Typically, this will happen due to the
# process being killed by a signal.
if not self._acquired:
# If the lock hasn't been aquired yet, the
# caller can check the returncode and handle
# this failure appropriately.
if not (self.cancelled or self._kill_test):
writemsg_level("_LockProcess: %s\n" % \
_("failed to acquire lock on '%s'") % (self.path,),
level=logging.ERROR, noiselevel=-1)
self._unregister()
self.returncode = proc.returncode
self.wait()
return
if not self.cancelled and \
not self._unlocked:
# We don't want lost locks going unnoticed, so it's
# only safe to ignore if either the cancel() or
# unlock() methods have been previously called.
raise AssertionError("lock process failed with returncode %s" \
% (proc.returncode,))
def _cancel(self):
if self._proc is not None:
self._proc.cancel()
def _poll(self):
if self._proc is not None:
self._proc.poll()
return self.returncode
def _output_handler(self, f, event):
buf = None
if event & self.scheduler.IO_IN:
try:
buf = os.read(self._files['pipe_in'], self._bufsize)
except OSError as e:
if e.errno not in (errno.EAGAIN,):
raise
if buf:
self._acquired = True
self._unregister()
self.returncode = os.EX_OK
self.wait()
return True
def _unregister(self):
self._registered = False
if self._reg_id is not None:
self.scheduler.source_remove(self._reg_id)
self._reg_id = None
if self._files is not None:
try:
pipe_in = self._files.pop('pipe_in')
except KeyError:
pass
else:
os.close(pipe_in)
def unlock(self):
if self._proc is None:
raise AssertionError('not locked')
if self.returncode is None:
raise AssertionError('lock not acquired yet')
if self.returncode != os.EX_OK:
raise AssertionError("lock process failed with returncode %s" \
% (self.returncode,))
self._unlocked = True
os.write(self._files['pipe_out'], b'\0')
os.close(self._files['pipe_out'])
self._files = None
self._proc.wait()
self._proc = None
class _LockProcess(AbstractPollTask):
"""
This uses the portage.locks module to acquire a lock asynchronously,
using a subprocess. After the lock is acquired, the process
writes to a pipe in order to notify a poll loop running in the main
process. The unlock() method notifies the subprocess to release the
lock and exit.
"""
__slots__ = ('path',) + \
('_acquired', '_kill_test', '_proc', '_files', '_reg_id', '_unlocked')
def _start(self):
in_pr, in_pw = os.pipe()
out_pr, out_pw = os.pipe()
self._files = {}
self._files['pipe_in'] = in_pr
self._files['pipe_out'] = out_pw
fcntl.fcntl(in_pr, fcntl.F_SETFL,
fcntl.fcntl(in_pr, fcntl.F_GETFL) | os.O_NONBLOCK)
self._reg_id = self.scheduler.register(in_pr,
self.scheduler.IO_IN, self._output_handler)
self._registered = True
self._proc = SpawnProcess(
args=[portage._python_interpreter,
os.path.join(portage._bin_path, 'lock-helper.py'), self.path],
env=dict(os.environ, PORTAGE_PYM_PATH=portage._pym_path),
fd_pipes={0:out_pr, 1:in_pw, 2:sys.stderr.fileno()},
scheduler=self.scheduler)
self._proc.addExitListener(self._proc_exit)
self._proc.start()
os.close(out_pr)
os.close(in_pw)
def _proc_exit(self, proc):
if self._files is not None:
# Close pipe_out if it's still open, since it's useless
# after the process has exited. This helps to avoid
# "ResourceWarning: unclosed file" since Python 3.2.
try:
pipe_out = self._files.pop('pipe_out')
except KeyError:
pass
else:
os.close(pipe_out)
if proc.returncode != os.EX_OK:
# Typically, this will happen due to the
# process being killed by a signal.
if not self._acquired:
# If the lock hasn't been aquired yet, the
# caller can check the returncode and handle
# this failure appropriately.
if not (self.cancelled or self._kill_test):
writemsg_level("_LockProcess: %s\n" % \
_("failed to acquire lock on '%s'") % (self.path,),
level=logging.ERROR, noiselevel=-1)
self._unregister()
self.returncode = proc.returncode
self.wait()
return
if not self.cancelled and \
not self._unlocked:
# We don't want lost locks going unnoticed, so it's
# only safe to ignore if either the cancel() or
# unlock() methods have been previously called.
raise AssertionError("lock process failed with returncode %s" \
% (proc.returncode,))
def _cancel(self):
if self._proc is not None:
self._proc.cancel()
def _poll(self):
if self._proc is not None:
self._proc.poll()
return self.returncode
def _output_handler(self, f, event):
buf = None
if event & self.scheduler.IO_IN:
try:
buf = os.read(self._files['pipe_in'], self._bufsize)
except OSError as e:
if e.errno not in (errno.EAGAIN,):
raise
if buf:
self._acquired = True
self._unregister()
self.returncode = os.EX_OK
self.wait()
return True
def _unregister(self):
self._registered = False
if self._reg_id is not None:
self.scheduler.unregister(self._reg_id)
self._reg_id = None
if self._files is not None:
try:
pipe_in = self._files.pop('pipe_in')
except KeyError:
pass
else:
os.close(pipe_in)
def unlock(self):
if self._proc is None:
raise AssertionError('not locked')
if self.returncode is None:
raise AssertionError('lock not acquired yet')
if self.returncode != os.EX_OK:
raise AssertionError("lock process failed with returncode %s" \
% (self.returncode,))
self._unlocked = True
os.write(self._files['pipe_out'], b'\0')
os.close(self._files['pipe_out'])
self._files = None
self._proc.wait()
self._proc = None
class _LockProcess(AbstractPollTask):
"""
This uses the portage.locks module to acquire a lock asynchronously,
using a subprocess. After the lock is acquired, the process
writes to a pipe in order to notify a poll loop running in the main
process. The unlock() method notifies the subprocess to release the
lock and exit.
"""
__slots__ = ('path',) + \
('_acquired', '_kill_test', '_proc', '_files', '_unlock_future')
def _start(self):
in_pr, in_pw = os.pipe()
out_pr, out_pw = os.pipe()
self._files = {}
self._files['pipe_in'] = in_pr
self._files['pipe_out'] = out_pw
fcntl.fcntl(in_pr, fcntl.F_SETFL,
fcntl.fcntl(in_pr, fcntl.F_GETFL) | os.O_NONBLOCK)
# FD_CLOEXEC is enabled by default in Python >=3.4.
if sys.hexversion < 0x3040000:
try:
fcntl.FD_CLOEXEC
except AttributeError:
pass
else:
fcntl.fcntl(in_pr, fcntl.F_SETFD,
fcntl.fcntl(in_pr, fcntl.F_GETFD) | fcntl.FD_CLOEXEC)
self.scheduler.add_reader(in_pr, self._output_handler)
self._registered = True
self._proc = SpawnProcess(
args=[portage._python_interpreter,
os.path.join(portage._bin_path, 'lock-helper.py'), self.path],
env=dict(os.environ, PORTAGE_PYM_PATH=portage._pym_path),
fd_pipes={0:out_pr, 1:in_pw, 2:sys.__stderr__.fileno()},
scheduler=self.scheduler)
self._proc.addExitListener(self._proc_exit)
self._proc.start()
os.close(out_pr)
os.close(in_pw)
def _proc_exit(self, proc):
if self._files is not None:
# Close pipe_out if it's still open, since it's useless
# after the process has exited. This helps to avoid
# "ResourceWarning: unclosed file" since Python 3.2.
try:
pipe_out = self._files.pop('pipe_out')
except KeyError:
pass
else:
os.close(pipe_out)
if proc.returncode != os.EX_OK:
# Typically, this will happen due to the
# process being killed by a signal.
if not self._acquired:
# If the lock hasn't been aquired yet, the
# caller can check the returncode and handle
# this failure appropriately.
if not (self.cancelled or self._kill_test):
writemsg_level("_LockProcess: %s\n" % \
_("failed to acquire lock on '%s'") % (self.path,),
level=logging.ERROR, noiselevel=-1)
self._unregister()
self.returncode = proc.returncode
self._async_wait()
return
if not self.cancelled and \
self._unlock_future is None:
# We don't want lost locks going unnoticed, so it's
# only safe to ignore if either the cancel() or
# unlock() methods have been previously called.
raise AssertionError("lock process failed with returncode %s" \
% (proc.returncode,))
if self._unlock_future is not None:
self._unlock_future.set_result(None)
def _cancel(self):
if self._proc is not None:
self._proc.cancel()
def _poll(self):
if self._proc is not None:
self._proc.poll()
return self.returncode
def _output_handler(self):
buf = self._read_buf(self._files['pipe_in'])
if buf:
self._acquired = True
self._unregister()
self.returncode = os.EX_OK
self._async_wait()
return True
def _unregister(self):
self._registered = False
if self._files is not None:
try:
pipe_in = self._files.pop('pipe_in')
except KeyError:
pass
else:
self.scheduler.remove_reader(pipe_in)
os.close(pipe_in)
def _unlock(self):
if self._proc is None:
raise AssertionError('not locked')
if not self._acquired:
raise AssertionError('lock not acquired yet')
if self.returncode != os.EX_OK:
raise AssertionError("lock process failed with returncode %s" \
% (self.returncode,))
if self._unlock_future is not None:
raise AssertionError("already unlocked")
self._unlock_future = self.scheduler.create_future()
os.write(self._files['pipe_out'], b'\0')
os.close(self._files['pipe_out'])
self._files = None
def async_unlock(self):
"""
Release the lock asynchronously. Release notification is available
via the add_done_callback method of the returned Future instance.
@returns: Future, result is None
"""
self._unlock()
return self._unlock_future
