Mercurial > hg
annotate hgext/fsmonitor/state.py @ 30539:29b35dac3b1f
fsmonitor: be robust in the face of bad state
fsmonitor could write out bad state if interrupted part way through, and
would then crash when it tried to read it back in.
Make both sides of the operation more robust - reading state should fail
cleanly, and we can use atomictemp to write out cleanly as the file is
small. Between the two, we shouldn't crash with an IndexError any more.
author | Simon Farnsworth <simonfar@fb.com> |
---|---|
date | Fri, 25 Nov 2016 07:30:46 -0800 |
parents | a0939666b836 |
children | 15c998528c36 |
rev | line source |
---|---|
28433
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
1 # state.py - fsmonitor persistent state |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
2 # |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
3 # Copyright 2013-2016 Facebook, Inc. |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
4 # |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
5 # This software may be used and distributed according to the terms of the |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
6 # GNU General Public License version 2 or any later version. |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
7 |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
8 from __future__ import absolute_import |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
9 |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
10 import errno |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
11 import os |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
12 import socket |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
13 import struct |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
14 |
29205
a0939666b836
py3: move up symbol imports to enforce import-checker rules
Yuya Nishihara <yuya@tcha.org>
parents:
28433
diff
changeset
|
15 from mercurial.i18n import _ |
28433
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
16 from mercurial import pathutil |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
17 |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
18 _version = 4 |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
19 _versionformat = ">I" |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
20 |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
21 class state(object): |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
22 def __init__(self, repo): |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
23 self._opener = repo.opener |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
24 self._ui = repo.ui |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
25 self._rootdir = pathutil.normasprefix(repo.root) |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
26 self._lastclock = None |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
27 |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
28 self.mode = self._ui.config('fsmonitor', 'mode', default='on') |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
29 self.walk_on_invalidate = self._ui.configbool( |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
30 'fsmonitor', 'walk_on_invalidate', False) |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
31 self.timeout = float(self._ui.config( |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
32 'fsmonitor', 'timeout', default='2')) |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
33 |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
34 def get(self): |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
35 try: |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
36 file = self._opener('fsmonitor.state', 'rb') |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
37 except IOError as inst: |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
38 if inst.errno != errno.ENOENT: |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
39 raise |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
40 return None, None, None |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
41 |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
42 versionbytes = file.read(4) |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
43 if len(versionbytes) < 4: |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
44 self._ui.log( |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
45 'fsmonitor', 'fsmonitor: state file only has %d bytes, ' |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
46 'nuking state\n' % len(versionbytes)) |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
47 self.invalidate() |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
48 return None, None, None |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
49 try: |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
50 diskversion = struct.unpack(_versionformat, versionbytes)[0] |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
51 if diskversion != _version: |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
52 # different version, nuke state and start over |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
53 self._ui.log( |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
54 'fsmonitor', 'fsmonitor: version switch from %d to ' |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
55 '%d, nuking state\n' % (diskversion, _version)) |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
56 self.invalidate() |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
57 return None, None, None |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
58 |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
59 state = file.read().split('\0') |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
60 # state = hostname\0clock\0ignorehash\0 + list of files, each |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
61 # followed by a \0 |
30539
29b35dac3b1f
fsmonitor: be robust in the face of bad state
Simon Farnsworth <simonfar@fb.com>
parents:
29205
diff
changeset
|
62 if len(state) < 3: |
29b35dac3b1f
fsmonitor: be robust in the face of bad state
Simon Farnsworth <simonfar@fb.com>
parents:
29205
diff
changeset
|
63 self._ui.log( |
29b35dac3b1f
fsmonitor: be robust in the face of bad state
Simon Farnsworth <simonfar@fb.com>
parents:
29205
diff
changeset
|
64 'fsmonitor', 'fsmonitor: state file truncated (expected ' |
29b35dac3b1f
fsmonitor: be robust in the face of bad state
Simon Farnsworth <simonfar@fb.com>
parents:
29205
diff
changeset
|
65 '3 chunks, found %d), nuking state\n', len(state)) |
29b35dac3b1f
fsmonitor: be robust in the face of bad state
Simon Farnsworth <simonfar@fb.com>
parents:
29205
diff
changeset
|
66 self.invalidate() |
29b35dac3b1f
fsmonitor: be robust in the face of bad state
Simon Farnsworth <simonfar@fb.com>
parents:
29205
diff
changeset
|
67 return None, None, None |
28433
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
68 diskhostname = state[0] |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
69 hostname = socket.gethostname() |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
70 if diskhostname != hostname: |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
71 # file got moved to a different host |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
72 self._ui.log('fsmonitor', 'fsmonitor: stored hostname "%s" ' |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
73 'different from current "%s", nuking state\n' % |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
74 (diskhostname, hostname)) |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
75 self.invalidate() |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
76 return None, None, None |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
77 |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
78 clock = state[1] |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
79 ignorehash = state[2] |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
80 # discard the value after the last \0 |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
81 notefiles = state[3:-1] |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
82 |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
83 finally: |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
84 file.close() |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
85 |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
86 return clock, ignorehash, notefiles |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
87 |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
88 def set(self, clock, ignorehash, notefiles): |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
89 if clock is None: |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
90 self.invalidate() |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
91 return |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
92 |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
93 try: |
30539
29b35dac3b1f
fsmonitor: be robust in the face of bad state
Simon Farnsworth <simonfar@fb.com>
parents:
29205
diff
changeset
|
94 file = self._opener('fsmonitor.state', 'wb', atomictemp=True) |
28433
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
95 except (IOError, OSError): |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
96 self._ui.warn(_("warning: unable to write out fsmonitor state\n")) |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
97 return |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
98 |
30539
29b35dac3b1f
fsmonitor: be robust in the face of bad state
Simon Farnsworth <simonfar@fb.com>
parents:
29205
diff
changeset
|
99 with file: |
28433
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
100 file.write(struct.pack(_versionformat, _version)) |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
101 file.write(socket.gethostname() + '\0') |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
102 file.write(clock + '\0') |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
103 file.write(ignorehash + '\0') |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
104 if notefiles: |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
105 file.write('\0'.join(notefiles)) |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
106 file.write('\0') |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
107 |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
108 def invalidate(self): |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
109 try: |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
110 os.unlink(os.path.join(self._rootdir, '.hg', 'fsmonitor.state')) |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
111 except OSError as inst: |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
112 if inst.errno != errno.ENOENT: |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
113 raise |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
114 |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
115 def setlastclock(self, clock): |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
116 self._lastclock = clock |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
117 |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
118 def getlastclock(self): |
3b67f27bb908
fsmonitor: new experimental extension
Martijn Pieters <mjpieters@fb.com>
parents:
diff
changeset
|
119 return self._lastclock |