This is an archive of the discontinued Mercurial Phabricator instance.

Differential D2463

wireprotoserver: support logging SSH server I/O to a file descriptor
ClosedPublic

Authored by indygreg on Feb 26 2018, 4:16 PM.

Details

Reviewers
durin42
Group Reviewers
hg-reviewers
Commits
rHG7cc4a9b9732a: wireprotoserver: support logging SSH server I/O to a file descriptor
rHG64efadb62026: wireprotoserver: support logging SSH server I/O to a file descriptor
Summary

We will soon introduce a debug command and tests for low-level I/O
behavior of the SSH wire protocol.

To facilitate this, we need to instrument the SSH server so it
can log its I/O as events occur.

We teach the SSH server to convert its stdout and stderr file objects
into file object proxies. We configure these proxies to log to a
file descriptor whose file number is specified via a config option.
The idea is to have a future debug command start the SSH server
process with access to an extra file descriptor that can be used
by the server process to log I/O. Monitoring only the write I/O
will be more robust than monitoring both writes and reads from the
client process because read operations are not deterministic. This
will matter for tests that capture raw I/O activity.

Diff Detail

Repository
rHG Mercurial
Lint
Automatic diff as part of commit; lint not applicable.
Unit
Automatic diff as part of commit; unit tests not applicable.

Event Timeline

indygreg created this revision.Feb 26 2018, 4:16 PM
indygreg updated this revision to Diff 6248.Mar 1 2018, 11:30 AM
durin42 accepted this revision.Mar 1 2018, 4:13 PM
This revision is now accepted and ready to land.Mar 1 2018, 4:13 PM
Closed by commit rHG64efadb62026: wireprotoserver: support logging SSH server I/O to a file descriptor (authored by indygreg). · Explain WhyMar 1 2018, 4:30 PM
This revision was automatically updated to reflect the committed changes.

Revision Contents
Changeset List

PathPackages
Mmercurial/wireprotoserver.py (9 lines)

Diff 6281

mercurial/wireprotoserver.py

elif state == 'shutdown': elif state == 'shutdown':
break break
else: else:
raise error.ProgrammingError('unhandled ssh server state: %s' % raise error.ProgrammingError('unhandled ssh server state: %s' %
state) state)
class sshserver(object): class sshserver(object):
def __init__(self, ui, repo): def __init__(self, ui, repo, logfh=None):
self._ui = ui self._ui = ui
self._repo = repo self._repo = repo
self._fin = ui.fin self._fin = ui.fin
self._fout = ui.fout self._fout = ui.fout
# Log write I/O to stdout and stderr if configured.
if logfh:
self._fout = util.makeloggingfileobject(
logfh, self._fout, 'o', logdata=True)
ui.ferr = util.makeloggingfileobject(
logfh, ui.ferr, 'e', logdata=True)
hook.redirect(True) hook.redirect(True)
ui.fout = repo.ui.fout = ui.ferr ui.fout = repo.ui.fout = ui.ferr
# Prevent insertion/deletion of CRs # Prevent insertion/deletion of CRs
util.setbinary(self._fin) util.setbinary(self._fin)
util.setbinary(self._fout) util.setbinary(self._fout)
def serve_forever(self): def serve_forever(self):
self.serveuntil(threading.Event()) self.serveuntil(threading.Event())
sys.exit(0) sys.exit(0)
def serveuntil(self, ev): def serveuntil(self, ev):
"""Serve until a threading.Event is set.""" """Serve until a threading.Event is set."""
_runsshserver(self._ui, self._repo, self._fin, self._fout, ev) _runsshserver(self._ui, self._repo, self._fin, self._fout, ev)