Mercurial > public > mercurial-scm > hg-stable
annotate mercurial/lock.py @ 1753:e6e70450edb9
Raise a different exception when the lock is not available
When the filesystem is read-only or if we have some other
error, there is no need to wait.
Raise a lock.LockUnavailable exception.
| author | Benoit Boissinot <benoit.boissinot@ens-lyon.org> |
|---|---|
| date | Mon, 20 Feb 2006 01:09:40 +0100 |
| parents | 59b3639df0a9 |
| children | e431344e604c |
| rev | line source |
|---|---|
| 161 | 1 # lock.py - simple locking scheme for mercurial |
| 2 # | |
| 3 # Copyright 2005 Matt Mackall <mpm@selenic.com> | |
| 4 # | |
| 5 # This software may be used and distributed according to the terms | |
| 6 # of the GNU General Public License, incorporated herein by reference. | |
| 7 | |
|
1753
e6e70450edb9
Raise a different exception when the lock is not available
Benoit Boissinot <benoit.boissinot@ens-lyon.org>
parents:
1559
diff
changeset
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8 import errno, os, time |
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422
10c43444a38e
[PATCH] Enables lock work under the other 'OS'
mpm@selenic.com
parents:
161
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9 import util |
| 161 | 10 |
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1753
e6e70450edb9
Raise a different exception when the lock is not available
Benoit Boissinot <benoit.boissinot@ens-lyon.org>
parents:
1559
diff
changeset
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11 class LockException(Exception): |
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e6e70450edb9
Raise a different exception when the lock is not available
Benoit Boissinot <benoit.boissinot@ens-lyon.org>
parents:
1559
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12 pass |
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e6e70450edb9
Raise a different exception when the lock is not available
Benoit Boissinot <benoit.boissinot@ens-lyon.org>
parents:
1559
diff
changeset
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13 class LockHeld(LockException): |
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Raise a different exception when the lock is not available
Benoit Boissinot <benoit.boissinot@ens-lyon.org>
parents:
1559
diff
changeset
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14 pass |
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e6e70450edb9
Raise a different exception when the lock is not available
Benoit Boissinot <benoit.boissinot@ens-lyon.org>
parents:
1559
diff
changeset
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15 class LockUnavailable(LockException): |
| 161 | 16 pass |
| 17 | |
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Convert all classes to new-style classes by deriving them from object.
Eric Hopper <hopper@omnifarious.org>
parents:
1530
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18 class lock(object): |
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1530
abfab59fce79
add a releasefn keyword to lock.lock
Benoit Boissinot <benoit.boissinot@ens-lyon.org>
parents:
1062
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changeset
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19 def __init__(self, file, wait=1, releasefn=None): |
| 161 | 20 self.f = file |
| 21 self.held = 0 | |
| 22 self.wait = wait | |
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1530
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add a releasefn keyword to lock.lock
Benoit Boissinot <benoit.boissinot@ens-lyon.org>
parents:
1062
diff
changeset
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23 self.releasefn = releasefn |
| 161 | 24 self.lock() |
| 25 | |
| 26 def __del__(self): | |
| 27 self.release() | |
| 28 | |
| 29 def lock(self): | |
| 30 while 1: | |
| 31 try: | |
| 32 self.trylock() | |
| 33 return 1 | |
| 34 except LockHeld, inst: | |
| 35 if self.wait: | |
| 36 time.sleep(1) | |
| 37 continue | |
| 38 raise inst | |
| 515 | 39 |
| 161 | 40 def trylock(self): |
| 41 pid = os.getpid() | |
| 42 try: | |
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parents:
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43 util.makelock(str(pid), self.f) |
| 161 | 44 self.held = 1 |
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1753
e6e70450edb9
Raise a different exception when the lock is not available
Benoit Boissinot <benoit.boissinot@ens-lyon.org>
parents:
1559
diff
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45 except (OSError, IOError), why: |
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Raise a different exception when the lock is not available
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parents:
1559
diff
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46 if why.errno == errno.EEXIST: |
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e6e70450edb9
Raise a different exception when the lock is not available
Benoit Boissinot <benoit.boissinot@ens-lyon.org>
parents:
1559
diff
changeset
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47 raise LockHeld(util.readlock(self.f)) |
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e6e70450edb9
Raise a different exception when the lock is not available
Benoit Boissinot <benoit.boissinot@ens-lyon.org>
parents:
1559
diff
changeset
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48 else: |
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Raise a different exception when the lock is not available
Benoit Boissinot <benoit.boissinot@ens-lyon.org>
parents:
1559
diff
changeset
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49 raise LockUnavailable(why) |
| 161 | 50 |
| 51 def release(self): | |
| 52 if self.held: | |
| 53 self.held = 0 | |
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1530
abfab59fce79
add a releasefn keyword to lock.lock
Benoit Boissinot <benoit.boissinot@ens-lyon.org>
parents:
1062
diff
changeset
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54 if self.releasefn: |
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abfab59fce79
add a releasefn keyword to lock.lock
Benoit Boissinot <benoit.boissinot@ens-lyon.org>
parents:
1062
diff
changeset
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55 self.releasefn() |
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503
c6a2e41c8c60
Fix troubles with clone and exception handling
mpm@selenic.com
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429
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56 try: |
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c6a2e41c8c60
Fix troubles with clone and exception handling
mpm@selenic.com
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57 os.unlink(self.f) |
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c6a2e41c8c60
Fix troubles with clone and exception handling
mpm@selenic.com
parents:
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58 except: pass |
| 161 | 59 |