Mercurial > hg
view tests/sshprotoext.py @ 42943:5fadf6103790
remotefilelog: replace repack lock to solve race condition
2c74337e6483 reduced the probability of race-conditions when starting
background repack and prefetch and we saw the difference in our CI instance
with all failures disappearing except one where one call to waitonrepack seems
to returns too early.
I'm not sure what exactly goes wrong but I realized that while the prefetch
operation uses a standard Mercurial lock, the repack operation is using a
custom lock based on `fcntl.flock` on available platforms. As `extutil.flock`
fallback on traditional Mercurial locks on other platforms and the tests are
stable on my laptop, our CI environment and GCC112, I'm sending this patch to
standardize the behavior across environments.
Differential Revision: https://phab.mercurial-scm.org/D6844
author | Boris Feld <boris.feld@octobus.net> |
---|---|
date | Wed, 11 Sep 2019 17:41:13 +0200 |
parents | b4d85bc122bd |
children | 2372284d9457 |
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# sshprotoext.py - Extension to test behavior of SSH protocol # # Copyright 2018 Gregory Szorc <gregory.szorc@gmail.com> # # This software may be used and distributed according to the terms of the # GNU General Public License version 2 or any later version. # This extension replaces the SSH server started via `hg serve --stdio`. # The server behaves differently depending on environment variables. from __future__ import absolute_import from mercurial import ( error, extensions, registrar, sshpeer, wireprotoserver, wireprotov1server, ) configtable = {} configitem = registrar.configitem(configtable) configitem(b'sshpeer', b'mode', default=None) configitem(b'sshpeer', b'handshake-mode', default=None) class bannerserver(wireprotoserver.sshserver): """Server that sends a banner to stdout.""" def serve_forever(self): for i in range(10): self._fout.write(b'banner: line %d\n' % i) super(bannerserver, self).serve_forever() class prehelloserver(wireprotoserver.sshserver): """Tests behavior when connecting to <0.9.1 servers. The ``hello`` wire protocol command was introduced in Mercurial 0.9.1. Modern clients send the ``hello`` command when connecting to SSH servers. This mock server tests behavior of the handshake when ``hello`` is not supported. """ def serve_forever(self): l = self._fin.readline() assert l == b'hello\n' # Respond to unknown commands with an empty reply. wireprotoserver._sshv1respondbytes(self._fout, b'') l = self._fin.readline() assert l == b'between\n' proto = wireprotoserver.sshv1protocolhandler(self._ui, self._fin, self._fout) rsp = wireprotov1server.dispatch(self._repo, proto, b'between') wireprotoserver._sshv1respondbytes(self._fout, rsp.data) super(prehelloserver, self).serve_forever() def performhandshake(orig, ui, stdin, stdout, stderr): """Wrapped version of sshpeer._performhandshake to send extra commands.""" mode = ui.config(b'sshpeer', b'handshake-mode') if mode == b'pre-no-args': ui.debug(b'sending no-args command\n') stdin.write(b'no-args\n') stdin.flush() return orig(ui, stdin, stdout, stderr) elif mode == b'pre-multiple-no-args': ui.debug(b'sending unknown1 command\n') stdin.write(b'unknown1\n') ui.debug(b'sending unknown2 command\n') stdin.write(b'unknown2\n') ui.debug(b'sending unknown3 command\n') stdin.write(b'unknown3\n') stdin.flush() return orig(ui, stdin, stdout, stderr) else: raise error.ProgrammingError(b'unknown HANDSHAKECOMMANDMODE: %s' % mode) def extsetup(ui): # It's easier for tests to define the server behavior via environment # variables than config options. This is because `hg serve --stdio` # has to be invoked with a certain form for security reasons and # `dummyssh` can't just add `--config` flags to the command line. servermode = ui.environ.get(b'SSHSERVERMODE') if servermode == b'banner': wireprotoserver.sshserver = bannerserver elif servermode == b'no-hello': wireprotoserver.sshserver = prehelloserver elif servermode: raise error.ProgrammingError(b'unknown server mode: %s' % servermode) peermode = ui.config(b'sshpeer', b'mode') if peermode == b'extra-handshake-commands': extensions.wrapfunction(sshpeer, '_performhandshake', performhandshake) elif peermode: raise error.ProgrammingError(b'unknown peer mode: %s' % peermode)