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
19
from bzrlib.lazy_import import lazy_import
20
lazy_import(globals(), """
22
from bzrlib.decorators import (needs_read_lock,
24
import bzrlib.errors as errors
25
from bzrlib.errors import BzrError
26
from bzrlib.osutils import file_iterator, safe_unicode
27
from bzrlib.symbol_versioning import (deprecated_method,
29
from bzrlib.trace import mutter, note
30
import bzrlib.transactions as transactions
31
import bzrlib.urlutils as urlutils
34
from bzrlib.decorators import (
37
from bzrlib.symbol_versioning import (
34
43
# XXX: The tracking here of lock counts and whether the lock is held is
35
44
# somewhat redundant with what's done in LockDir; the main difference is that
36
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)
38
64
class LockableFiles(object):
39
65
"""Object representing a set of related files locked within the same scope.
41
These files are used by a WorkingTree, Repository or Branch, and should
42
generally only be touched by that object.
44
LockableFiles also provides some policy on top of Transport for encoding
45
control files as utf-8.
67
This coordinates access to the lock along with providing a transaction.
47
69
LockableFiles manage a lock count and can be locked repeatedly by
48
70
a single caller. (The underlying lock implementation generally does not
51
73
Instances of this class are often called control_files.
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
53
This object builds on top of a Transport, which is used to actually write
54
the files to disk, and an OSLock or LockDir, which controls how access to
55
the files is controlled. The particular type of locking used is set when
56
the object is constructed. In older formats OSLocks are used everywhere.
57
in newer formats a LockDir is used for Repositories and Branches, and
58
OSLocks for the local filesystem.
79
:ivar _lock: The real underlying lock (e.g. a LockDir)
80
:ivar _counted_lock: A lock decorated with a semaphore, so that it
61
84
# _lock_mode: None, or 'r' or 'w'
63
86
# _lock_count: If _lock_mode is true, a positive count of the number of
64
# times the lock has been taken *by this process*.
66
# If set to False (by a plugin, etc) BzrBranch will not set the
67
# mode on created files or directories
87
# times the lock has been taken *by this process*.
71
89
def __init__(self, transport, lock_name, lock_class):
72
90
"""Create a LockableFiles group
74
:param transport: Transport pointing to the directory holding the
92
:param transport: Transport pointing to the directory holding the
75
93
control files and lock.
76
94
:param lock_name: Name of the lock guarding these files.
77
95
:param lock_class: Class of lock strategy to use: typically
118
129
self._lock.break_lock()
120
131
def _escape(self, file_or_path):
132
"""DEPRECATED: Do not use outside this class"""
121
133
if not isinstance(file_or_path, basestring):
122
134
file_or_path = '/'.join(file_or_path)
123
135
if file_or_path == '':
125
return urlutils.escape(safe_unicode(file_or_path))
137
return urlutils.escape(osutils.safe_unicode(file_or_path))
127
139
def _find_modes(self):
128
"""Determine the appropriate modes for files and directories."""
140
"""Determine the appropriate modes for files and directories.
142
:deprecated: Replaced by BzrDir._find_creation_modes.
144
# XXX: The properties created by this can be removed or deprecated
145
# once all the _get_text_store methods etc no longer use them.
130
148
st = self._transport.stat('.')
131
149
except errors.TransportNotPossible:
132
150
self._dir_mode = 0755
133
151
self._file_mode = 0644
135
self._dir_mode = st.st_mode & 07777
153
# Check the directory mode, but also make sure the created
154
# directories and files are read-write for this user. This is
155
# mostly a workaround for filesystems which lie about being able to
156
# write to a directory (cygwin & win32)
157
self._dir_mode = (st.st_mode & 07777) | 00700
136
158
# Remove the sticky and execute bits for files
137
159
self._file_mode = self._dir_mode & ~07111
138
if not self._set_dir_mode:
139
self._dir_mode = None
140
if not self._set_file_mode:
141
self._file_mode = None
143
def controlfilename(self, file_or_path):
144
"""Return location relative to branch."""
145
return self._transport.abspath(self._escape(file_or_path))
147
@deprecated_method(zero_eight)
148
def controlfile(self, file_or_path, mode='r'):
149
"""Open a control file for this branch.
151
There are two classes of file in a lockable directory: text
152
and binary. binary files are untranslated byte streams. Text
153
control files are stored with Unix newlines and in UTF-8, even
154
if the platform or locale defaults are different.
156
Such files are not openable in write mode : they are managed via
157
put and put_utf8 which atomically replace old versions using
161
relpath = self._escape(file_or_path)
162
# TODO: codecs.open() buffers linewise, so it was overloaded with
163
# a much larger buffer, do we need to do the same for getreader/getwriter?
165
return self.get(relpath)
167
raise BzrError("Branch.controlfile(mode='wb') is not supported, use put[_utf8]")
169
return self.get_utf8(relpath)
171
raise BzrError("Branch.controlfile(mode='w') is not supported, use put[_utf8]")
173
raise BzrError("invalid controlfile mode %r" % mode)
176
def get(self, relpath):
177
"""Get a file as a bytestream."""
178
relpath = self._escape(relpath)
179
return self._transport.get(relpath)
182
def get_utf8(self, relpath):
183
"""Get a file as a unicode stream."""
184
relpath = self._escape(relpath)
185
# DO NOT introduce an errors=replace here.
186
return codecs.getreader('utf-8')(self._transport.get(relpath))
189
def put(self, path, file):
192
:param path: The path to put the file, relative to the .bzr control
194
:param f: A file-like or string object whose contents should be copied.
196
self._transport.put_file(self._escape(path), file, mode=self._file_mode)
199
def put_bytes(self, path, a_string):
200
"""Write a string of bytes.
202
:param path: The path to put the bytes, relative to the transport root.
203
:param string: A string object, whose exact bytes are to be copied.
205
self._transport.put_bytes(self._escape(path), a_string,
206
mode=self._file_mode)
209
def put_utf8(self, path, a_string):
210
"""Write a string, encoding as utf-8.
212
:param path: The path to put the string, relative to the transport root.
213
:param string: A string or unicode object whose contents should be copied.
215
# IterableFile would not be needed if Transport.put took iterables
216
# instead of files. ADHB 2005-12-25
217
# RBC 20060103 surely its not needed anyway, with codecs transcode
219
# JAM 20060103 We definitely don't want encode(..., 'replace')
220
# these are valuable files which should have exact contents.
221
if not isinstance(a_string, basestring):
222
raise errors.BzrBadParameterNotString(a_string)
223
self.put_bytes(path, a_string.encode('utf-8'))
225
161
def leave_in_place(self):
226
162
"""Set this LockableFiles to not clear the physical lock on unlock."""
245
181
some other way, and need to synchronise this object's state with that
248
# mutter("lock write: %s (%s)", self, self._lock_count)
249
184
# TODO: Upgrade locking to support using a Transport,
250
185
# and potentially a remote locking protocol
251
186
if self._lock_mode:
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
#note('write locking %s', self)
260
194
#traceback.print_stack()
261
195
self._lock_mode = 'w'
263
self._set_transaction(transactions.WriteTransaction())
196
self._lock_warner.lock_count = 1
197
self._set_write_transaction()
264
198
self._token_from_lock = token_from_lock
265
199
return token_from_lock
267
201
def lock_read(self):
268
# mutter("lock read: %s (%s)", self, self._lock_count)
269
202
if self._lock_mode:
270
assert self._lock_mode in ('r', 'w'), \
271
"invalid lock mode %r" % self._lock_mode
272
self._lock_count += 1
203
if self._lock_mode not in ('r', 'w'):
204
raise ValueError("invalid lock mode %r" % (self._lock_mode,))
205
self._lock_warner.lock_count += 1
274
207
self._lock.lock_read()
275
#note('read locking %s', self)
276
208
#traceback.print_stack()
277
209
self._lock_mode = 'r'
279
self._set_transaction(transactions.ReadOnlyTransaction())
280
# 5K may be excessive, but hey, its a knob.
281
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)
283
224
def unlock(self):
284
# mutter("unlock: %s (%s)", self, self._lock_count)
285
225
if not self._lock_mode:
286
raise errors.LockNotHeld(self)
287
if self._lock_count > 1:
288
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
290
#note('unlocking %s', self)
291
230
#traceback.print_stack()
292
231
self._finish_transaction()
294
233
self._lock.unlock()
296
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
298
241
def is_locked(self):
299
242
"""Return true if this LockableFiles group is locked"""
300
return self._lock_count >= 1
243
return self._lock_warner.lock_count >= 1
302
245
def get_physical_lock_status(self):
303
246
"""Return physical lock status.
305
248
Returns true if a lock is held on the transport. If no lock is held, or
306
249
the underlying locking mechanism does not support querying lock
307
250
status, false is returned.
added
removed
bzrlib/lockable_files.py
