diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/mailman/bin/arch.py | 2 | ||||
| -rw-r--r-- | src/mailman/bin/master.py | 71 |
2 files changed, 68 insertions, 5 deletions
diff --git a/src/mailman/bin/arch.py b/src/mailman/bin/arch.py index a27fa8d7f..abf057c3f 100644 --- a/src/mailman/bin/arch.py +++ b/src/mailman/bin/arch.py @@ -15,6 +15,8 @@ # You should have received a copy of the GNU General Public License along with # GNU Mailman. If not, see <http://www.gnu.org/licenses/>. +from __future__ import absolute_import, unicode_literals + import os import sys import errno diff --git a/src/mailman/bin/master.py b/src/mailman/bin/master.py index 829468883..579583c67 100644 --- a/src/mailman/bin/master.py +++ b/src/mailman/bin/master.py @@ -220,6 +220,66 @@ Exiting.""") +class PIDWatcher: + """A class which safely manages child process ids.""" + + def __init__(self): + self._pids = {} + + def __iter__(self): + # Safely iterate over all the keys in the dictionary. Because + # asynchronous signals are involved, the dictionary's size could + # change during iteration. Iterate over a copy of the keys to avoid + # that. + for pid in self._pids.keys(): + yield pid + + def add(self, pid, info): + """Add process information. + + :param pid: The process id. The watcher must not already be tracking + this process id. + :type pid: int + :param info: The process information. + :type info: 4-tuple consisting of + (queue-runner-name, slice-number, slice-count, restart-count) + """ + old_info = self._pids.get(pid) + assert old_info is None, ( + 'Duplicate process id {0} with existing info: {1}'.format( + pid, old_info)) + self._pids[pid] = info + + def pop(self, pid): + """Remove and return existing process information. + + :param pid: The process id. The watcher must already be tracking this + process id. + :type pid: int + :return: The process information. + :rtype: 4-tuple consisting of + (queue-runner-name, slice-number, slice-count, restart-count) + :raise KeyError: if the process id is not being tracked. + """ + return self._pids.pop(pid) + + def drop(self, pid): + """Remove and return existing process information. + + This is like `pop()` except that no `KeyError` is raised if the + process id is not being tracked. + + :param pid: The process id. + :type pid: int + :return: The process information, or None if the process id is not + being tracked. + :rtype: 4-tuple consisting of + (queue-runner-name, slice-number, slice-count, restart-count) + """ + return self._pids.pop(pid, None) + + + class Loop: """Main control loop class.""" @@ -227,7 +287,7 @@ class Loop: self._lock = lock self._restartable = restartable self._config_file = config_file - self._kids = {} + self._kids = PIDWatcher() def install_signal_handlers(self): """Install various signals handlers for control from mailmanctl.""" @@ -336,7 +396,7 @@ class Loop: pid = self._start_runner(spec) log = logging.getLogger('mailman.qrunner') log.debug('[%d] %s', pid, spec) - self._kids[pid] = info + self._kids.add(pid, info) def loop(self): """Main loop. @@ -394,8 +454,9 @@ qrunner %s reached maximum restart limit of %d, not restarting.""", # SIGTERM or we aren't restarting. if restart: spec = '%s:%d:%d' % (qrname, slice_number, count) - newpid = self._start_runner(spec) - self._kids[newpid] = (qrname, slice_number, count, restarts) + new_pid = self._start_runner(spec) + new_info = (qrname, slice_number, count, restarts) + self._kids.add(new_pid, new_info) def cleanup(self): """Ensure that all children have exited.""" @@ -414,7 +475,7 @@ qrunner %s reached maximum restart limit of %d, not restarting.""", try: # pylint: disable-msg=W0612 pid, status = os.wait() - del self._kids[pid] + self._kids.drop(pid) except OSError, e: if e.errno == errno.ECHILD: break |