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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17
from __future__ import absolute_import
19
from bzrlib.lazy_import import lazy_import
20
lazy_import(globals(), """
33
from bzrlib.decorators import (
15
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
17
from cStringIO import StringIO
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
# XXX: The tracking here of lock counts and whether the lock is held is
35
# somewhat redundant with what's done in LockDir; the main difference is that
36
# LockableFiles permits reentrancy.
38
38
class LockableFiles(object):
39
39
"""Object representing a set of related files locked within the same scope.
41
This coordinates access to the lock along with providing a transaction.
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.
43
47
LockableFiles manage a lock count and can be locked repeatedly by
44
48
a single caller. (The underlying lock implementation generally does not
47
51
Instances of this class are often called control_files.
49
This class is now deprecated; code should move to using the Transport
50
directly for file operations and using the lock or CountedLock for
53
:ivar _lock: The real underlying lock (e.g. a LockDir)
54
:ivar _lock_count: If _lock_mode is true, a positive count of the number
55
of times the lock has been taken (and not yet released) *by this
56
process*, through this particular object instance.
57
:ivar _lock_mode: None, or 'r' or 'w'
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.
61
# _lock_mode: None, or 'r' or 'w'
63
# _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
60
71
def __init__(self, transport, lock_name, lock_class):
61
72
"""Create a LockableFiles group
63
:param transport: Transport pointing to the directory holding the
74
:param transport: Transport pointing to the directory holding the
64
75
control files and lock.
65
76
:param lock_name: Name of the lock guarding these files.
66
77
:param lock_class: Class of lock strategy to use: typically
101
118
self._lock.break_lock()
103
120
def _escape(self, file_or_path):
104
"""DEPRECATED: Do not use outside this class"""
105
121
if not isinstance(file_or_path, basestring):
106
122
file_or_path = '/'.join(file_or_path)
107
123
if file_or_path == '':
109
return urlutils.escape(osutils.safe_unicode(file_or_path))
125
return urlutils.escape(safe_unicode(file_or_path))
111
127
def _find_modes(self):
112
"""Determine the appropriate modes for files and directories.
114
:deprecated: Replaced by BzrDir._find_creation_modes.
116
# XXX: The properties created by this can be removed or deprecated
117
# once all the _get_text_store methods etc no longer use them.
128
"""Determine the appropriate modes for files and directories."""
120
130
st = self._transport.stat('.')
121
131
except errors.TransportNotPossible:
122
132
self._dir_mode = 0755
123
133
self._file_mode = 0644
125
# Check the directory mode, but also make sure the created
126
# directories and files are read-write for this user. This is
127
# mostly a workaround for filesystems which lie about being able to
128
# write to a directory (cygwin & win32)
129
self._dir_mode = (st.st_mode & 07777) | 00700
135
self._dir_mode = st.st_mode & 07777
130
136
# Remove the sticky and execute bits for files
131
137
self._file_mode = self._dir_mode & ~07111
133
def leave_in_place(self):
134
"""Set this LockableFiles to not clear the physical lock on unlock."""
135
self._lock.leave_in_place()
137
def dont_leave_in_place(self):
138
"""Set this LockableFiles to clear the physical lock on unlock."""
139
self._lock.dont_leave_in_place()
141
def lock_write(self, token=None):
142
"""Lock this group of files for writing.
144
:param token: if this is already locked, then lock_write will fail
145
unless the token matches the existing lock.
146
:returns: a token if this instance supports tokens, otherwise None.
147
:raises TokenLockingNotSupported: when a token is given but this
148
instance doesn't support using token locks.
149
:raises MismatchedToken: if the specified token doesn't match the token
150
of the existing lock.
152
A token should be passed in if you know that you have locked the object
153
some other way, and need to synchronise this object's state with that
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_utf8(self, path, a_string):
200
"""Write a string, encoding as utf-8.
202
:param path: The path to put the string, relative to the transport root.
203
:param string: A file-like or string object whose contents should be copied.
205
# IterableFile would not be needed if Transport.put took iterables
206
# instead of files. ADHB 2005-12-25
207
# RBC 20060103 surely its not needed anyway, with codecs transcode
209
# JAM 20060103 We definitely don't want encode(..., 'replace')
210
# these are valuable files which should have exact contents.
211
if not isinstance(a_string, basestring):
212
raise errors.BzrBadParameterNotString(a_string)
213
self.put(path, StringIO(a_string.encode('utf-8')))
215
def lock_write(self):
216
# mutter("lock write: %s (%s)", self, self._lock_count)
217
# TODO: Upgrade locking to support using a Transport,
218
# and potentially a remote locking protocol
156
219
if self._lock_mode:
157
if (self._lock_mode != 'w'
158
or not self.get_transaction().writeable()):
220
if self._lock_mode != 'w' or not self.get_transaction().writeable():
159
221
raise errors.ReadOnlyError(self)
160
self._lock.validate_token(token)
161
222
self._lock_count += 1
162
return self._token_from_lock
164
token_from_lock = self._lock.lock_write(token=token)
224
self._lock.lock_write()
225
#note('write locking %s', self)
165
226
#traceback.print_stack()
166
227
self._lock_mode = 'w'
167
228
self._lock_count = 1
168
self._set_write_transaction()
169
self._token_from_lock = token_from_lock
170
return token_from_lock
229
self._set_transaction(transactions.WriteTransaction())
172
231
def lock_read(self):
232
# mutter("lock read: %s (%s)", self, self._lock_count)
173
233
if self._lock_mode:
174
if self._lock_mode not in ('r', 'w'):
175
raise ValueError("invalid lock mode %r" % (self._lock_mode,))
234
assert self._lock_mode in ('r', 'w'), \
235
"invalid lock mode %r" % self._lock_mode
176
236
self._lock_count += 1
178
238
self._lock.lock_read()
239
#note('read locking %s', self)
179
240
#traceback.print_stack()
180
241
self._lock_mode = 'r'
181
242
self._lock_count = 1
182
self._set_read_transaction()
184
def _set_read_transaction(self):
185
"""Setup a read transaction."""
186
self._set_transaction(transactions.ReadOnlyTransaction())
187
# 5K may be excessive, but hey, its a knob.
188
self.get_transaction().set_cache_size(5000)
190
def _set_write_transaction(self):
191
"""Setup a write transaction."""
192
self._set_transaction(transactions.WriteTransaction())
194
@only_raises(errors.LockNotHeld, errors.LockBroken)
243
self._set_transaction(transactions.ReadOnlyTransaction())
244
# 5K may be excessive, but hey, its a knob.
245
self.get_transaction().set_cache_size(5000)
195
247
def unlock(self):
248
# mutter("unlock: %s (%s)", self, self._lock_count)
196
249
if not self._lock_mode:
197
return lock.cant_unlock_not_held(self)
250
raise errors.LockNotHeld(self)
198
251
if self._lock_count > 1:
199
252
self._lock_count -= 1
254
#note('unlocking %s', self)
201
255
#traceback.print_stack()
202
256
self._finish_transaction()
added
removed
bzrlib/lockable_files.py
