Mercurial > hg
view hgext/fsmonitor/state.py @ 33087:fcd1c483f5ea
strip: add a delayedstrip method that works in a transaction
For long, the fact that strip does not work inside a transaction and some
code has to work with both obsstore and fallback to strip lead to duplicated
code like:
with repo.transaction():
....
if obsstore:
obsstore.createmarkers(...)
if not obsstore:
repair.strip(...)
Things get more complex when you want to call something which may call strip
under the hood. Like you cannot simply write:
with repo.transaction():
....
rebasemod.rebase(...) # may call "strip", so this doesn't work
But you do want rebase to run inside a same transaction if possible, so the
code may look like:
with repo.transaction():
....
if obsstore:
rebasemod.rebase(...)
obsstore.createmarkers(...)
if not obsstore:
rebasemod.rebase(...)
repair.strip(...)
That's ugly and error-prone. Ideally it's possible to just write:
with repo.transaction():
rebasemod.rebase(...)
saferemovenodes(...)
This patch is the first step towards that. It adds a "delayedstrip" method
to repair.py which maintains a postclose callback in the transaction object.
author | Jun Wu <quark@fb.com> |
---|---|
date | Sun, 25 Jun 2017 10:38:45 -0700 |
parents | 1b25c648d5b7 |
children | 718f7acd6d5e |
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# state.py - fsmonitor persistent state # # Copyright 2013-2016 Facebook, Inc. # # This software may be used and distributed according to the terms of the # GNU General Public License version 2 or any later version. from __future__ import absolute_import import errno import os import socket import struct from mercurial.i18n import _ from mercurial import ( pathutil, util, ) _version = 4 _versionformat = ">I" class state(object): def __init__(self, repo): self._vfs = repo.vfs self._ui = repo.ui self._rootdir = pathutil.normasprefix(repo.root) self._lastclock = None self._identity = util.filestat(None) self.mode = self._ui.config('fsmonitor', 'mode', default='on') self.walk_on_invalidate = self._ui.configbool( 'fsmonitor', 'walk_on_invalidate', False) self.timeout = float(self._ui.config( 'fsmonitor', 'timeout', default='2')) def get(self): try: file = self._vfs('fsmonitor.state', 'rb') except IOError as inst: self._identity = util.filestat(None) if inst.errno != errno.ENOENT: raise return None, None, None self._identity = util.filestat.fromfp(file) versionbytes = file.read(4) if len(versionbytes) < 4: self._ui.log( 'fsmonitor', 'fsmonitor: state file only has %d bytes, ' 'nuking state\n' % len(versionbytes)) self.invalidate() return None, None, None try: diskversion = struct.unpack(_versionformat, versionbytes)[0] if diskversion != _version: # different version, nuke state and start over self._ui.log( 'fsmonitor', 'fsmonitor: version switch from %d to ' '%d, nuking state\n' % (diskversion, _version)) self.invalidate() return None, None, None state = file.read().split('\0') # state = hostname\0clock\0ignorehash\0 + list of files, each # followed by a \0 if len(state) < 3: self._ui.log( 'fsmonitor', 'fsmonitor: state file truncated (expected ' '3 chunks, found %d), nuking state\n', len(state)) self.invalidate() return None, None, None diskhostname = state[0] hostname = socket.gethostname() if diskhostname != hostname: # file got moved to a different host self._ui.log('fsmonitor', 'fsmonitor: stored hostname "%s" ' 'different from current "%s", nuking state\n' % (diskhostname, hostname)) self.invalidate() return None, None, None clock = state[1] ignorehash = state[2] # discard the value after the last \0 notefiles = state[3:-1] finally: file.close() return clock, ignorehash, notefiles def set(self, clock, ignorehash, notefiles): if clock is None: self.invalidate() return # Read the identity from the file on disk rather than from the open file # pointer below, because the latter is actually a brand new file. identity = util.filestat.frompath(self._vfs.join('fsmonitor.state')) if identity != self._identity: self._ui.debug('skip updating fsmonitor.state: identity mismatch\n') return try: file = self._vfs('fsmonitor.state', 'wb', atomictemp=True, checkambig=True) except (IOError, OSError): self._ui.warn(_("warning: unable to write out fsmonitor state\n")) return with file: file.write(struct.pack(_versionformat, _version)) file.write(socket.gethostname() + '\0') file.write(clock + '\0') file.write(ignorehash + '\0') if notefiles: file.write('\0'.join(notefiles)) file.write('\0') def invalidate(self): try: os.unlink(os.path.join(self._rootdir, '.hg', 'fsmonitor.state')) except OSError as inst: if inst.errno != errno.ENOENT: raise self._identity = util.filestat(None) def setlastclock(self, clock): self._lastclock = clock def getlastclock(self): return self._lastclock