annotate mercurial/lock.py @ 32076:d7b698ae153b stable

help: explain how to access subtopics in internals
author Matt DeVore <matvore@google.com>
date Wed, 19 Apr 2017 17:04:22 -0700
parents 2e48c776a874
children e1938d6051da
Ignore whitespace changes - Everywhere: Within whitespace: At end of lines:
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1 # lock.py - simple advisory locking scheme for mercurial
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2 #
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3 # Copyright 2005, 2006 Matt Mackall <mpm@selenic.com>
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4 #
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5 # This software may be used and distributed according to the terms of the
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6 # GNU General Public License version 2 or any later version.
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7
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8 from __future__ import absolute_import
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9
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10 import contextlib
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11 import errno
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12 import os
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13 import socket
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14 import time
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15 import warnings
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16
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17 from . import (
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18 encoding,
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19 error,
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20 pycompat,
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21 util,
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22 )
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23
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24 def _getlockprefix():
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25 """Return a string which is used to differentiate pid namespaces
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26
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27 It's useful to detect "dead" processes and remove stale locks with
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28 confidence. Typically it's just hostname. On modern linux, we include an
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29 extra Linux-specific pid namespace identifier.
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30 """
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31 result = socket.gethostname()
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32 if pycompat.ispy3:
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33 result = result.encode(pycompat.sysstr(encoding.encoding), 'replace')
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34 if pycompat.sysplatform.startswith('linux'):
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35 try:
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36 result += '/%x' % os.stat('/proc/self/ns/pid').st_ino
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37 except OSError as ex:
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38 if ex.errno not in (errno.ENOENT, errno.EACCES, errno.ENOTDIR):
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39 raise
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40 return result
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41
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42 class lock(object):
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43 '''An advisory lock held by one process to control access to a set
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44 of files. Non-cooperating processes or incorrectly written scripts
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45 can ignore Mercurial's locking scheme and stomp all over the
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46 repository, so don't do that.
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47
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48 Typically used via localrepository.lock() to lock the repository
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49 store (.hg/store/) or localrepository.wlock() to lock everything
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50 else under .hg/.'''
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51
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52 # lock is symlink on platforms that support it, file on others.
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53
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54 # symlink is used because create of directory entry and contents
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55 # are atomic even over nfs.
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56
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57 # old-style lock: symlink to pid
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58 # new-style lock: symlink to hostname:pid
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59
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60 _host = None
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61
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62 def __init__(self, vfs, file, timeout=-1, releasefn=None, acquirefn=None,
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63 desc=None, inheritchecker=None, parentlock=None):
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64 self.vfs = vfs
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65 self.f = file
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66 self.held = 0
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67 self.timeout = timeout
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68 self.releasefn = releasefn
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69 self.acquirefn = acquirefn
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70 self.desc = desc
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71 self._inheritchecker = inheritchecker
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72 self.parentlock = parentlock
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73 self._parentheld = False
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74 self._inherited = False
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75 self.postrelease = []
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76 self.pid = self._getpid()
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77 self.delay = self.lock()
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78 if self.acquirefn:
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79 self.acquirefn()
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80
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81 def __enter__(self):
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82 return self
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83
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84 def __exit__(self, exc_type, exc_value, exc_tb):
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85 self.release()
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86
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87 def __del__(self):
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88 if self.held:
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89 warnings.warn("use lock.release instead of del lock",
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90 category=DeprecationWarning,
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91 stacklevel=2)
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92
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93 # ensure the lock will be removed
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94 # even if recursive locking did occur
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95 self.held = 1
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96
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97 self.release()
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98
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99 def _getpid(self):
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100 # wrapper around util.getpid() to make testing easier
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101 return util.getpid()
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102
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103 def lock(self):
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104 timeout = self.timeout
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105 while True:
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106 try:
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107 self._trylock()
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108 return self.timeout - timeout
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109 except error.LockHeld as inst:
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110 if timeout != 0:
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111 time.sleep(1)
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112 if timeout > 0:
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113 timeout -= 1
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114 continue
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115 raise error.LockHeld(errno.ETIMEDOUT, inst.filename, self.desc,
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116 inst.locker)
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117
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118 def _trylock(self):
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119 if self.held:
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120 self.held += 1
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121 return
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122 if lock._host is None:
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123 lock._host = _getlockprefix()
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124 lockname = '%s:%d' % (lock._host, self.pid)
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125 retry = 5
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126 while not self.held and retry:
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127 retry -= 1
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128 try:
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129 self.vfs.makelock(lockname, self.f)
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130 self.held = 1
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131 except (OSError, IOError) as why:
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132 if why.errno == errno.EEXIST:
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133 locker = self._readlock()
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134 # special case where a parent process holds the lock -- this
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135 # is different from the pid being different because we do
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136 # want the unlock and postrelease functions to be called,
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137 # but the lockfile to not be removed.
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138 if locker == self.parentlock:
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Siddharth Agarwal <sid0@fb.com>
parents: 26383
diff changeset
139 self._parentheld = True
e16f80f89a29 lock: recognize parent locks while acquiring
Siddharth Agarwal <sid0@fb.com>
parents: 26383
diff changeset
140 self.held = 1
e16f80f89a29 lock: recognize parent locks while acquiring
Siddharth Agarwal <sid0@fb.com>
parents: 26383
diff changeset
141 return
e16f80f89a29 lock: recognize parent locks while acquiring
Siddharth Agarwal <sid0@fb.com>
parents: 26383
diff changeset
142 locker = self._testlock(locker)
3686
4308f4cdc07b Don't step into an endless loop when lock file is empty.
Thomas Arendsen Hein <thomas@intevation.de>
parents: 2859
diff changeset
143 if locker is not None:
20091
abfe6a8e619b lock: take both vfs and lock file path relative to vfs to access via vfs
FUJIWARA Katsunori <foozy@lares.dti.ne.jp>
parents: 19927
diff changeset
144 raise error.LockHeld(errno.EAGAIN,
abfe6a8e619b lock: take both vfs and lock file path relative to vfs to access via vfs
FUJIWARA Katsunori <foozy@lares.dti.ne.jp>
parents: 19927
diff changeset
145 self.vfs.join(self.f), self.desc,
7640
7197812e8d44 error: move lock errors
Matt Mackall <mpm@selenic.com>
parents: 4959
diff changeset
146 locker)
1877
d314a89fa4f1 change lock format to let us detect and break stale locks.
Vadim Gelfer <vadim.gelfer@gmail.com>
parents: 1836
diff changeset
147 else:
7640
7197812e8d44 error: move lock errors
Matt Mackall <mpm@selenic.com>
parents: 4959
diff changeset
148 raise error.LockUnavailable(why.errno, why.strerror,
7197812e8d44 error: move lock errors
Matt Mackall <mpm@selenic.com>
parents: 4959
diff changeset
149 why.filename, self.desc)
1877
d314a89fa4f1 change lock format to let us detect and break stale locks.
Vadim Gelfer <vadim.gelfer@gmail.com>
parents: 1836
diff changeset
150
26290
9664d32bd6cb lock: factor code to read lock into a separate function
Siddharth Agarwal <sid0@fb.com>
parents: 26082
diff changeset
151 def _readlock(self):
9664d32bd6cb lock: factor code to read lock into a separate function
Siddharth Agarwal <sid0@fb.com>
parents: 26082
diff changeset
152 """read lock and return its value
9664d32bd6cb lock: factor code to read lock into a separate function
Siddharth Agarwal <sid0@fb.com>
parents: 26082
diff changeset
153
9664d32bd6cb lock: factor code to read lock into a separate function
Siddharth Agarwal <sid0@fb.com>
parents: 26082
diff changeset
154 Returns None if no lock exists, pid for old-style locks, and host:pid
9664d32bd6cb lock: factor code to read lock into a separate function
Siddharth Agarwal <sid0@fb.com>
parents: 26082
diff changeset
155 for new-style locks.
9664d32bd6cb lock: factor code to read lock into a separate function
Siddharth Agarwal <sid0@fb.com>
parents: 26082
diff changeset
156 """
9664d32bd6cb lock: factor code to read lock into a separate function
Siddharth Agarwal <sid0@fb.com>
parents: 26082
diff changeset
157 try:
9664d32bd6cb lock: factor code to read lock into a separate function
Siddharth Agarwal <sid0@fb.com>
parents: 26082
diff changeset
158 return self.vfs.readlock(self.f)
9664d32bd6cb lock: factor code to read lock into a separate function
Siddharth Agarwal <sid0@fb.com>
parents: 26082
diff changeset
159 except (OSError, IOError) as why:
9664d32bd6cb lock: factor code to read lock into a separate function
Siddharth Agarwal <sid0@fb.com>
parents: 26082
diff changeset
160 if why.errno == errno.ENOENT:
9664d32bd6cb lock: factor code to read lock into a separate function
Siddharth Agarwal <sid0@fb.com>
parents: 26082
diff changeset
161 return None
9664d32bd6cb lock: factor code to read lock into a separate function
Siddharth Agarwal <sid0@fb.com>
parents: 26082
diff changeset
162 raise
9664d32bd6cb lock: factor code to read lock into a separate function
Siddharth Agarwal <sid0@fb.com>
parents: 26082
diff changeset
163
26291
1d33842c5b3e lock: factor out lock testing into a separate function
Siddharth Agarwal <sid0@fb.com>
parents: 26290
diff changeset
164 def _testlock(self, locker):
26290
9664d32bd6cb lock: factor code to read lock into a separate function
Siddharth Agarwal <sid0@fb.com>
parents: 26082
diff changeset
165 if locker is None:
9664d32bd6cb lock: factor code to read lock into a separate function
Siddharth Agarwal <sid0@fb.com>
parents: 26082
diff changeset
166 return None
2579
0875cda033fd use __contains__, index or split instead of str.find
Benoit Boissinot <benoit.boissinot@ens-lyon.org>
parents: 2016
diff changeset
167 try:
0875cda033fd use __contains__, index or split instead of str.find
Benoit Boissinot <benoit.boissinot@ens-lyon.org>
parents: 2016
diff changeset
168 host, pid = locker.split(":", 1)
0875cda033fd use __contains__, index or split instead of str.find
Benoit Boissinot <benoit.boissinot@ens-lyon.org>
parents: 2016
diff changeset
169 except ValueError:
1877
d314a89fa4f1 change lock format to let us detect and break stale locks.
Vadim Gelfer <vadim.gelfer@gmail.com>
parents: 1836
diff changeset
170 return locker
4947
3e25a6eb5c9a lock.py: cache hostname, but not pid, in case we fork
Bryan O'Sullivan <bos@serpentine.com>
parents: 3877
diff changeset
171 if host != lock._host:
1877
d314a89fa4f1 change lock format to let us detect and break stale locks.
Vadim Gelfer <vadim.gelfer@gmail.com>
parents: 1836
diff changeset
172 return locker
161
0b4c5cb953d9 Simply repository locking
mpm@selenic.com
parents:
diff changeset
173 try:
2579
0875cda033fd use __contains__, index or split instead of str.find
Benoit Boissinot <benoit.boissinot@ens-lyon.org>
parents: 2016
diff changeset
174 pid = int(pid)
9685
a820cd39d415 lock: catch specific exceptions
Benoit Boissinot <benoit.boissinot@ens-lyon.org>
parents: 9680
diff changeset
175 except ValueError:
1877
d314a89fa4f1 change lock format to let us detect and break stale locks.
Vadim Gelfer <vadim.gelfer@gmail.com>
parents: 1836
diff changeset
176 return locker
d314a89fa4f1 change lock format to let us detect and break stale locks.
Vadim Gelfer <vadim.gelfer@gmail.com>
parents: 1836
diff changeset
177 if util.testpid(pid):
d314a89fa4f1 change lock format to let us detect and break stale locks.
Vadim Gelfer <vadim.gelfer@gmail.com>
parents: 1836
diff changeset
178 return locker
d314a89fa4f1 change lock format to let us detect and break stale locks.
Vadim Gelfer <vadim.gelfer@gmail.com>
parents: 1836
diff changeset
179 # if locker dead, break lock. must do this with another lock
d314a89fa4f1 change lock format to let us detect and break stale locks.
Vadim Gelfer <vadim.gelfer@gmail.com>
parents: 1836
diff changeset
180 # held, or can race and break valid lock.
d314a89fa4f1 change lock format to let us detect and break stale locks.
Vadim Gelfer <vadim.gelfer@gmail.com>
parents: 1836
diff changeset
181 try:
20091
abfe6a8e619b lock: take both vfs and lock file path relative to vfs to access via vfs
FUJIWARA Katsunori <foozy@lares.dti.ne.jp>
parents: 19927
diff changeset
182 l = lock(self.vfs, self.f + '.break', timeout=0)
abfe6a8e619b lock: take both vfs and lock file path relative to vfs to access via vfs
FUJIWARA Katsunori <foozy@lares.dti.ne.jp>
parents: 19927
diff changeset
183 self.vfs.unlink(self.f)
1877
d314a89fa4f1 change lock format to let us detect and break stale locks.
Vadim Gelfer <vadim.gelfer@gmail.com>
parents: 1836
diff changeset
184 l.release()
7640
7197812e8d44 error: move lock errors
Matt Mackall <mpm@selenic.com>
parents: 4959
diff changeset
185 except error.LockError:
1877
d314a89fa4f1 change lock format to let us detect and break stale locks.
Vadim Gelfer <vadim.gelfer@gmail.com>
parents: 1836
diff changeset
186 return locker
161
0b4c5cb953d9 Simply repository locking
mpm@selenic.com
parents:
diff changeset
187
26291
1d33842c5b3e lock: factor out lock testing into a separate function
Siddharth Agarwal <sid0@fb.com>
parents: 26290
diff changeset
188 def testlock(self):
1d33842c5b3e lock: factor out lock testing into a separate function
Siddharth Agarwal <sid0@fb.com>
parents: 26290
diff changeset
189 """return id of locker if lock is valid, else None.
1d33842c5b3e lock: factor out lock testing into a separate function
Siddharth Agarwal <sid0@fb.com>
parents: 26290
diff changeset
190
1d33842c5b3e lock: factor out lock testing into a separate function
Siddharth Agarwal <sid0@fb.com>
parents: 26290
diff changeset
191 If old-style lock, we cannot tell what machine locker is on.
1d33842c5b3e lock: factor out lock testing into a separate function
Siddharth Agarwal <sid0@fb.com>
parents: 26290
diff changeset
192 with new-style lock, if locker is on this machine, we can
1d33842c5b3e lock: factor out lock testing into a separate function
Siddharth Agarwal <sid0@fb.com>
parents: 26290
diff changeset
193 see if locker is alive. If locker is on this machine but
1d33842c5b3e lock: factor out lock testing into a separate function
Siddharth Agarwal <sid0@fb.com>
parents: 26290
diff changeset
194 not alive, we can safely break lock.
1d33842c5b3e lock: factor out lock testing into a separate function
Siddharth Agarwal <sid0@fb.com>
parents: 26290
diff changeset
195
1d33842c5b3e lock: factor out lock testing into a separate function
Siddharth Agarwal <sid0@fb.com>
parents: 26290
diff changeset
196 The lock file is only deleted when None is returned.
1d33842c5b3e lock: factor out lock testing into a separate function
Siddharth Agarwal <sid0@fb.com>
parents: 26290
diff changeset
197
1d33842c5b3e lock: factor out lock testing into a separate function
Siddharth Agarwal <sid0@fb.com>
parents: 26290
diff changeset
198 """
1d33842c5b3e lock: factor out lock testing into a separate function
Siddharth Agarwal <sid0@fb.com>
parents: 26290
diff changeset
199 locker = self._readlock()
1d33842c5b3e lock: factor out lock testing into a separate function
Siddharth Agarwal <sid0@fb.com>
parents: 26290
diff changeset
200 return self._testlock(locker)
1d33842c5b3e lock: factor out lock testing into a separate function
Siddharth Agarwal <sid0@fb.com>
parents: 26290
diff changeset
201
26473
5f94e64f182c lock: turn prepinherit/reacquire into a single context manager
Siddharth Agarwal <sid0@fb.com>
parents: 26387
diff changeset
202 @contextlib.contextmanager
5f94e64f182c lock: turn prepinherit/reacquire into a single context manager
Siddharth Agarwal <sid0@fb.com>
parents: 26387
diff changeset
203 def inherit(self):
5f94e64f182c lock: turn prepinherit/reacquire into a single context manager
Siddharth Agarwal <sid0@fb.com>
parents: 26387
diff changeset
204 """context for the lock to be inherited by a Mercurial subprocess.
26357
6979a1369185 lock: add a method to prepare the lock for inheritance
Siddharth Agarwal <sid0@fb.com>
parents: 26356
diff changeset
205
26473
5f94e64f182c lock: turn prepinherit/reacquire into a single context manager
Siddharth Agarwal <sid0@fb.com>
parents: 26387
diff changeset
206 Yields a string that will be recognized by the lock in the subprocess.
5f94e64f182c lock: turn prepinherit/reacquire into a single context manager
Siddharth Agarwal <sid0@fb.com>
parents: 26387
diff changeset
207 Communicating this string to the subprocess needs to be done separately
5f94e64f182c lock: turn prepinherit/reacquire into a single context manager
Siddharth Agarwal <sid0@fb.com>
parents: 26387
diff changeset
208 -- typically by an environment variable.
26357
6979a1369185 lock: add a method to prepare the lock for inheritance
Siddharth Agarwal <sid0@fb.com>
parents: 26356
diff changeset
209 """
6979a1369185 lock: add a method to prepare the lock for inheritance
Siddharth Agarwal <sid0@fb.com>
parents: 26356
diff changeset
210 if not self.held:
6979a1369185 lock: add a method to prepare the lock for inheritance
Siddharth Agarwal <sid0@fb.com>
parents: 26356
diff changeset
211 raise error.LockInheritanceContractViolation(
26473
5f94e64f182c lock: turn prepinherit/reacquire into a single context manager
Siddharth Agarwal <sid0@fb.com>
parents: 26387
diff changeset
212 'inherit can only be called while lock is held')
26357
6979a1369185 lock: add a method to prepare the lock for inheritance
Siddharth Agarwal <sid0@fb.com>
parents: 26356
diff changeset
213 if self._inherited:
6979a1369185 lock: add a method to prepare the lock for inheritance
Siddharth Agarwal <sid0@fb.com>
parents: 26356
diff changeset
214 raise error.LockInheritanceContractViolation(
26473
5f94e64f182c lock: turn prepinherit/reacquire into a single context manager
Siddharth Agarwal <sid0@fb.com>
parents: 26387
diff changeset
215 'inherit cannot be called while lock is already inherited')
26498
e8564e04382d lock: add a way to prevent locks from being inherited
Siddharth Agarwal <sid0@fb.com>
parents: 26474
diff changeset
216 if self._inheritchecker is not None:
e8564e04382d lock: add a way to prevent locks from being inherited
Siddharth Agarwal <sid0@fb.com>
parents: 26474
diff changeset
217 self._inheritchecker()
26357
6979a1369185 lock: add a method to prepare the lock for inheritance
Siddharth Agarwal <sid0@fb.com>
parents: 26356
diff changeset
218 if self.releasefn:
6979a1369185 lock: add a method to prepare the lock for inheritance
Siddharth Agarwal <sid0@fb.com>
parents: 26356
diff changeset
219 self.releasefn()
6979a1369185 lock: add a method to prepare the lock for inheritance
Siddharth Agarwal <sid0@fb.com>
parents: 26356
diff changeset
220 if self._parentheld:
6979a1369185 lock: add a method to prepare the lock for inheritance
Siddharth Agarwal <sid0@fb.com>
parents: 26356
diff changeset
221 lockname = self.parentlock
6979a1369185 lock: add a method to prepare the lock for inheritance
Siddharth Agarwal <sid0@fb.com>
parents: 26356
diff changeset
222 else:
6979a1369185 lock: add a method to prepare the lock for inheritance
Siddharth Agarwal <sid0@fb.com>
parents: 26356
diff changeset
223 lockname = '%s:%s' % (lock._host, self.pid)
6979a1369185 lock: add a method to prepare the lock for inheritance
Siddharth Agarwal <sid0@fb.com>
parents: 26356
diff changeset
224 self._inherited = True
26473
5f94e64f182c lock: turn prepinherit/reacquire into a single context manager
Siddharth Agarwal <sid0@fb.com>
parents: 26387
diff changeset
225 try:
5f94e64f182c lock: turn prepinherit/reacquire into a single context manager
Siddharth Agarwal <sid0@fb.com>
parents: 26387
diff changeset
226 yield lockname
5f94e64f182c lock: turn prepinherit/reacquire into a single context manager
Siddharth Agarwal <sid0@fb.com>
parents: 26387
diff changeset
227 finally:
5f94e64f182c lock: turn prepinherit/reacquire into a single context manager
Siddharth Agarwal <sid0@fb.com>
parents: 26387
diff changeset
228 if self.acquirefn:
5f94e64f182c lock: turn prepinherit/reacquire into a single context manager
Siddharth Agarwal <sid0@fb.com>
parents: 26387
diff changeset
229 self.acquirefn()
5f94e64f182c lock: turn prepinherit/reacquire into a single context manager
Siddharth Agarwal <sid0@fb.com>
parents: 26387
diff changeset
230 self._inherited = False
26358
de5a52e5eb9e lock: add a method to reacquire the lock after subprocesses exit
Siddharth Agarwal <sid0@fb.com>
parents: 26357
diff changeset
231
161
0b4c5cb953d9 Simply repository locking
mpm@selenic.com
parents:
diff changeset
232 def release(self):
15583
926a06f7a353 lock: add mechanism to register post release callback
Pierre-Yves David <pierre-yves.david@ens-lyon.org>
parents: 14494
diff changeset
233 """release the lock and execute callback function if any
926a06f7a353 lock: add mechanism to register post release callback
Pierre-Yves David <pierre-yves.david@ens-lyon.org>
parents: 14494
diff changeset
234
17537
31f32a96e1e3 Merge spelling fixes
Bryan O'Sullivan <bryano@fb.com>
parents: 17427 17510
diff changeset
235 If the lock has been acquired multiple times, the actual release is
17510
7c44b703657b spelling: release
timeless@mozdev.org
parents: 15589
diff changeset
236 delayed to the last release call."""
8108
a26d33749bd8 made repo locks recursive and deprecate refcounting based lock releasing
Ronny Pfannschmidt <Ronny.Pfannschmidt@gmx.de>
parents: 7640
diff changeset
237 if self.held > 1:
a26d33749bd8 made repo locks recursive and deprecate refcounting based lock releasing
Ronny Pfannschmidt <Ronny.Pfannschmidt@gmx.de>
parents: 7640
diff changeset
238 self.held -= 1
9680
8cea86d73887 lock: use '==' instead of 'is' for integer equality ('is' may not work)
Benoit Boissinot <benoit.boissinot@ens-lyon.org>
parents: 9309
diff changeset
239 elif self.held == 1:
161
0b4c5cb953d9 Simply repository locking
mpm@selenic.com
parents:
diff changeset
240 self.held = 0
26383
0fceb34806e1 lock: add a wrapper to os.getpid() to make testing easier
Siddharth Agarwal <sid0@fb.com>
parents: 26359
diff changeset
241 if self._getpid() != self.pid:
18907
af9fa8d4c939 lock: if we fork, ensure that only the parent releases
Bryan O'Sullivan <bryano@fb.com>
parents: 17683
diff changeset
242 # we forked, and are not the parent
af9fa8d4c939 lock: if we fork, ensure that only the parent releases
Bryan O'Sullivan <bryano@fb.com>
parents: 17683
diff changeset
243 return
503
c6a2e41c8c60 Fix troubles with clone and exception handling
mpm@selenic.com
parents: 429
diff changeset
244 try:
23032
f484be02bd35 lock: while releasing, unlink lockfile even if the release function throws
Siddharth Agarwal <sid0@fb.com>
parents: 20380
diff changeset
245 if self.releasefn:
f484be02bd35 lock: while releasing, unlink lockfile even if the release function throws
Siddharth Agarwal <sid0@fb.com>
parents: 20380
diff changeset
246 self.releasefn()
f484be02bd35 lock: while releasing, unlink lockfile even if the release function throws
Siddharth Agarwal <sid0@fb.com>
parents: 20380
diff changeset
247 finally:
26359
c545d51c901e lock.release: do not unlink inherited locks
Siddharth Agarwal <sid0@fb.com>
parents: 26358
diff changeset
248 if not self._parentheld:
c545d51c901e lock.release: do not unlink inherited locks
Siddharth Agarwal <sid0@fb.com>
parents: 26358
diff changeset
249 try:
c545d51c901e lock.release: do not unlink inherited locks
Siddharth Agarwal <sid0@fb.com>
parents: 26358
diff changeset
250 self.vfs.unlink(self.f)
c545d51c901e lock.release: do not unlink inherited locks
Siddharth Agarwal <sid0@fb.com>
parents: 26358
diff changeset
251 except OSError:
c545d51c901e lock.release: do not unlink inherited locks
Siddharth Agarwal <sid0@fb.com>
parents: 26358
diff changeset
252 pass
26474
431094a3b21f lock.release: don't call postrelease functions for inherited locks
Siddharth Agarwal <sid0@fb.com>
parents: 26473
diff changeset
253 # The postrelease functions typically assume the lock is not held
431094a3b21f lock.release: don't call postrelease functions for inherited locks
Siddharth Agarwal <sid0@fb.com>
parents: 26473
diff changeset
254 # at all.
431094a3b21f lock.release: don't call postrelease functions for inherited locks
Siddharth Agarwal <sid0@fb.com>
parents: 26473
diff changeset
255 if not self._parentheld:
431094a3b21f lock.release: don't call postrelease functions for inherited locks
Siddharth Agarwal <sid0@fb.com>
parents: 26473
diff changeset
256 for callback in self.postrelease:
431094a3b21f lock.release: don't call postrelease functions for inherited locks
Siddharth Agarwal <sid0@fb.com>
parents: 26473
diff changeset
257 callback()
28959
518c3e392f75 lock: clear postrelease hooks list after usage
Gregory Szorc <gregory.szorc@gmail.com>
parents: 28027
diff changeset
258 # Prevent double usage and help clear cycles.
518c3e392f75 lock: clear postrelease hooks list after usage
Gregory Szorc <gregory.szorc@gmail.com>
parents: 28027
diff changeset
259 self.postrelease = None
161
0b4c5cb953d9 Simply repository locking
mpm@selenic.com
parents:
diff changeset
260
8108
a26d33749bd8 made repo locks recursive and deprecate refcounting based lock releasing
Ronny Pfannschmidt <Ronny.Pfannschmidt@gmx.de>
parents: 7640
diff changeset
261 def release(*locks):
a26d33749bd8 made repo locks recursive and deprecate refcounting based lock releasing
Ronny Pfannschmidt <Ronny.Pfannschmidt@gmx.de>
parents: 7640
diff changeset
262 for lock in locks:
a26d33749bd8 made repo locks recursive and deprecate refcounting based lock releasing
Ronny Pfannschmidt <Ronny.Pfannschmidt@gmx.de>
parents: 7640
diff changeset
263 if lock is not None:
a26d33749bd8 made repo locks recursive and deprecate refcounting based lock releasing
Ronny Pfannschmidt <Ronny.Pfannschmidt@gmx.de>
parents: 7640
diff changeset
264 lock.release()