13
13
# You should have received a copy of the GNU General Public License
14
14
# along with this program; if not, write to the Free Software
15
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
15
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17
17
from cStringIO import StringIO
43
44
# somewhat redundant with what's done in LockDir; the main difference is that
44
45
# LockableFiles permits reentrancy.
47
class _LockWarner(object):
48
"""Hold a counter for a lock and warn if GCed while the count is >= 1.
50
This is separate from LockableFiles because putting a __del__ on
51
LockableFiles can result in uncollectable cycles.
54
def __init__(self, repr):
59
if self.lock_count >= 1:
60
# There should have been a try/finally to unlock this.
61
warnings.warn("%r was gc'd while locked" % self.repr)
46
64
class LockableFiles(object):
47
65
"""Object representing a set of related files locked within the same scope.
49
These files are used by a WorkingTree, Repository or Branch, and should
50
generally only be touched by that object.
52
LockableFiles also provides some policy on top of Transport for encoding
53
control files as utf-8.
67
This coordinates access to the lock along with providing a transaction.
55
69
LockableFiles manage a lock count and can be locked repeatedly by
56
70
a single caller. (The underlying lock implementation generally does not
59
73
Instances of this class are often called control_files.
61
This object builds on top of a Transport, which is used to actually write
62
the files to disk, and an OSLock or LockDir, which controls how access to
63
the files is controlled. The particular type of locking used is set when
64
the object is constructed. In older formats OSLocks are used everywhere.
65
in newer formats a LockDir is used for Repositories and Branches, and
66
OSLocks for the local filesystem.
68
This class is now deprecated; code should move to using the Transport
69
directly for file operations and using the lock or CountedLock for
75
This class is now deprecated; code should move to using the Transport
76
directly for file operations and using the lock or CountedLock for
79
:ivar _lock: The real underlying lock (e.g. a LockDir)
80
:ivar _counted_lock: A lock decorated with a semaphore, so that it
73
84
# _lock_mode: None, or 'r' or 'w'
75
86
# _lock_count: If _lock_mode is true, a positive count of the number of
76
# times the lock has been taken *by this process*.
87
# times the lock has been taken *by this process*.
78
89
def __init__(self, transport, lock_name, lock_class):
79
90
"""Create a LockableFiles group
81
:param transport: Transport pointing to the directory holding the
92
:param transport: Transport pointing to the directory holding the
82
93
control files and lock.
83
94
:param lock_name: Name of the lock guarding these files.
84
95
:param lock_class: Class of lock strategy to use: typically
148
158
# Remove the sticky and execute bits for files
149
159
self._file_mode = self._dir_mode & ~07111
151
@deprecated_method(deprecated_in((1, 6, 0)))
152
def controlfilename(self, file_or_path):
153
"""Return location relative to branch.
155
:deprecated: Use Transport methods instead.
157
return self._transport.abspath(self._escape(file_or_path))
160
@deprecated_method(deprecated_in((1, 5, 0)))
161
def get(self, relpath):
162
"""Get a file as a bytestream.
164
:deprecated: Use a Transport instead of LockableFiles.
166
relpath = self._escape(relpath)
167
return self._transport.get(relpath)
170
@deprecated_method(deprecated_in((1, 5, 0)))
171
def get_utf8(self, relpath):
172
"""Get a file as a unicode stream.
174
:deprecated: Use a Transport instead of LockableFiles.
176
relpath = self._escape(relpath)
177
# DO NOT introduce an errors=replace here.
178
return codecs.getreader('utf-8')(self._transport.get(relpath))
181
@deprecated_method(deprecated_in((1, 6, 0)))
182
def put(self, path, file):
185
:param path: The path to put the file, relative to the .bzr control
187
:param file: A file-like or string object whose contents should be copied.
189
:deprecated: Use Transport methods instead.
191
self._transport.put_file(self._escape(path), file, mode=self._file_mode)
194
@deprecated_method(deprecated_in((1, 6, 0)))
195
def put_bytes(self, path, a_string):
196
"""Write a string of bytes.
198
:param path: The path to put the bytes, relative to the transport root.
199
:param a_string: A string object, whose exact bytes are to be copied.
201
:deprecated: Use Transport methods instead.
203
self._transport.put_bytes(self._escape(path), a_string,
204
mode=self._file_mode)
207
@deprecated_method(deprecated_in((1, 6, 0)))
208
def put_utf8(self, path, a_string):
209
"""Write a string, encoding as utf-8.
211
:param path: The path to put the string, relative to the transport root.
212
:param string: A string or unicode object whose contents should be copied.
214
:deprecated: Use Transport methods instead.
216
# IterableFile would not be needed if Transport.put took iterables
217
# instead of files. ADHB 2005-12-25
218
# RBC 20060103 surely its not needed anyway, with codecs transcode
220
# JAM 20060103 We definitely don't want encode(..., 'replace')
221
# these are valuable files which should have exact contents.
222
if not isinstance(a_string, basestring):
223
raise errors.BzrBadParameterNotString(a_string)
224
self.put_bytes(path, a_string.encode('utf-8'))
226
161
def leave_in_place(self):
227
162
"""Set this LockableFiles to not clear the physical lock on unlock."""
228
163
self._lock.leave_in_place()
252
187
if self._lock_mode != 'w' or not self.get_transaction().writeable():
253
188
raise errors.ReadOnlyError(self)
254
189
self._lock.validate_token(token)
255
self._lock_count += 1
190
self._lock_warner.lock_count += 1
256
191
return self._token_from_lock
258
193
token_from_lock = self._lock.lock_write(token=token)
259
194
#traceback.print_stack()
260
195
self._lock_mode = 'w'
262
self._set_transaction(transactions.WriteTransaction())
196
self._lock_warner.lock_count = 1
197
self._set_write_transaction()
263
198
self._token_from_lock = token_from_lock
264
199
return token_from_lock
267
202
if self._lock_mode:
268
203
if self._lock_mode not in ('r', 'w'):
269
204
raise ValueError("invalid lock mode %r" % (self._lock_mode,))
270
self._lock_count += 1
205
self._lock_warner.lock_count += 1
272
207
self._lock.lock_read()
273
208
#traceback.print_stack()
274
209
self._lock_mode = 'r'
276
self._set_transaction(transactions.ReadOnlyTransaction())
277
# 5K may be excessive, but hey, its a knob.
278
self.get_transaction().set_cache_size(5000)
210
self._lock_warner.lock_count = 1
211
self._set_read_transaction()
213
def _set_read_transaction(self):
214
"""Setup a read transaction."""
215
self._set_transaction(transactions.ReadOnlyTransaction())
216
# 5K may be excessive, but hey, its a knob.
217
self.get_transaction().set_cache_size(5000)
219
def _set_write_transaction(self):
220
"""Setup a write transaction."""
221
self._set_transaction(transactions.WriteTransaction())
223
@only_raises(errors.LockNotHeld, errors.LockBroken)
280
224
def unlock(self):
281
225
if not self._lock_mode:
282
raise errors.LockNotHeld(self)
283
if self._lock_count > 1:
284
self._lock_count -= 1
226
return lock.cant_unlock_not_held(self)
227
if self._lock_warner.lock_count > 1:
228
self._lock_warner.lock_count -= 1
286
230
#traceback.print_stack()
287
231
self._finish_transaction()
289
233
self._lock.unlock()
291
self._lock_mode = self._lock_count = None
235
self._lock_mode = self._lock_warner.lock_count = None
238
def _lock_count(self):
239
return self._lock_warner.lock_count
293
241
def is_locked(self):
294
242
"""Return true if this LockableFiles group is locked"""
295
return self._lock_count >= 1
243
return self._lock_warner.lock_count >= 1
297
245
def get_physical_lock_status(self):
298
246
"""Return physical lock status.
300
248
Returns true if a lock is held on the transport. If no lock is held, or
301
249
the underlying locking mechanism does not support querying lock
302
250
status, false is returned.
added
removed
bzrlib/lockable_files.py
