view hgext/fsmonitor/state.py @ 35449:24528dba0e64

run-tests: add substitution patterns for common '\' path output on Windows

The goal is to reduce the amount of hand tuning of new/changed tests that is
required on Windows.  Since the OS prints the proper paths everywhere else, this
is limited to Windows.  These are based on the check-code rules that were
dropped in 5feb782c7a95.

There are some minor tweaks, because those were trying to detect '/' paths
without a '(glob)' at the end, whereas these detect '\' paths. Also, it looks
like the 'no changes made to subrepo' one was broke, because the path to the
subrepo has been getting output but was not in the pattern.  End anchors are
dropped because '(glob)' is no longer required, but '(feature !)' annotations
are a possibility.

The 'saved backup bundle' pattern dropped from run-tests.py was simply carrying
over the first capture group.  The replace() method runs prior to evaluating
'\1', but it wasn't doing anything because of the 'r' prefix on '\\'.

The 'not recording move' entry is new, because I stumbled upon it searching for
some of these patterns.  There are probably others.

# 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')
        self.walk_on_invalidate = self._ui.configbool(
            'fsmonitor', 'walk_on_invalidate')
        self.timeout = float(self._ui.config('fsmonitor', 'timeout'))

    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