1
# Copyright (C) 2005 Canonical Ltd
1
# Copyright (C) 2005, 2006, 2008 Canonical Ltd
3
3
# This program is free software; you can redistribute it and/or modify
4
4
# it under the terms of the GNU General Public License as published by
5
5
# the Free Software Foundation; either version 2 of the License, or
6
6
# (at your option) any later version.
8
8
# This program is distributed in the hope that it will be useful,
9
9
# but WITHOUT ANY WARRANTY; without even the implied warranty of
10
10
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11
11
# GNU General Public License for more details.
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
15
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
17
17
from cStringIO import StringIO
19
from bzrlib.lazy_import import lazy_import
20
lazy_import(globals(), """
21
from bzrlib.decorators import *
22
import bzrlib.errors as errors
23
from bzrlib.errors import LockError, ReadOnlyError
24
from bzrlib.osutils import file_iterator, safe_unicode
25
from bzrlib.symbol_versioning import *
26
from bzrlib.symbol_versioning import deprecated_method, zero_eight
27
from bzrlib.trace import mutter
28
import bzrlib.transactions as transactions
32
from bzrlib.decorators import (
36
from bzrlib.symbol_versioning import (
42
# XXX: The tracking here of lock counts and whether the lock is held is
43
# somewhat redundant with what's done in LockDir; the main difference is that
44
# LockableFiles permits reentrancy.
31
46
class LockableFiles(object):
32
"""Object representing a set of files locked within the same scope
38
If _lock_mode is true, a positive count of the number of times the
39
lock has been taken *by this process*. Others may have compatible
43
Lock object from bzrlib.lock.
47
"""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.
55
LockableFiles manage a lock count and can be locked repeatedly by
56
a single caller. (The underlying lock implementation generally does not
59
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
49
# If set to False (by a plugin, etc) BzrBranch will not set the
50
# mode on created files or directories
54
def __init__(self, transport, lock_name):
73
# _lock_mode: None, or 'r' or 'w'
75
# _lock_count: If _lock_mode is true, a positive count of the number of
76
# times the lock has been taken *by this process*.
78
def __init__(self, transport, lock_name, lock_class):
79
"""Create a LockableFiles group
81
:param transport: Transport pointing to the directory holding the
82
control files and lock.
83
:param lock_name: Name of the lock guarding these files.
84
:param lock_class: Class of lock strategy to use: typically
85
either LockDir or TransportLock.
56
87
self._transport = transport
57
88
self.lock_name = lock_name
58
89
self._transaction = None
90
self._lock_mode = None
93
esc_name = self._escape(lock_name)
94
self._lock = lock_class(transport, esc_name,
95
file_modebits=self._file_mode,
96
dir_modebits=self._dir_mode)
98
def create_lock(self):
101
This should normally be called only when the LockableFiles directory
102
is first created on disk.
104
self._lock.create(mode=self._dir_mode)
107
return '%s(%r)' % (self.__class__.__name__,
110
return 'LockableFiles(%s, %s)' % (self.lock_name, self._transport.base)
61
112
def __del__(self):
62
if self._lock_mode or self._lock:
63
# XXX: This should show something every time, and be suitable for
64
# headless operation and embedding
65
from warnings import warn
66
warn("file group %r was not explicitly unlocked" % self)
114
# do not automatically unlock; there should have been a
115
# try/finally to unlock this.
116
warnings.warn("%r was gc'd while locked" % self)
118
def break_lock(self):
119
"""Break the lock of this lockable files group if it is held.
121
The current ui factory will be used to prompt for user conformation.
123
self._lock.break_lock()
69
125
def _escape(self, file_or_path):
70
126
if not isinstance(file_or_path, basestring):
71
127
file_or_path = '/'.join(file_or_path)
72
128
if file_or_path == '':
74
return bzrlib.transport.urlescape(safe_unicode(file_or_path))
130
return urlutils.escape(osutils.safe_unicode(file_or_path))
76
132
def _find_modes(self):
77
"""Determine the appropriate modes for files and directories."""
133
"""Determine the appropriate modes for files and directories.
135
:deprecated: Replaced by BzrDir._find_modes.
80
st = self._transport.stat('.')
81
except errors.NoSuchFile:
82
# The .bzr/ directory doesn't exist, try to
83
# inherit the permissions from the parent directory
84
# but only try 1 level up
85
temp_transport = self._transport.clone('..')
86
st = temp_transport.stat('.')
87
except (errors.TransportNotPossible, errors.NoSuchFile):
138
st = self._transport.stat('.')
139
except errors.TransportNotPossible:
88
140
self._dir_mode = 0755
89
141
self._file_mode = 0644
91
self._dir_mode = st.st_mode & 07777
143
# Check the directory mode, but also make sure the created
144
# directories and files are read-write for this user. This is
145
# mostly a workaround for filesystems which lie about being able to
146
# write to a directory (cygwin & win32)
147
self._dir_mode = (st.st_mode & 07777) | 00700
92
148
# Remove the sticky and execute bits for files
93
149
self._file_mode = self._dir_mode & ~07111
94
if not self._set_dir_mode:
96
if not self._set_file_mode:
97
self._file_mode = None
151
@deprecated_method(deprecated_in((1, 6, 0)))
99
152
def controlfilename(self, file_or_path):
100
"""Return location relative to branch."""
153
"""Return location relative to branch.
155
:deprecated: Use Transport methods instead.
101
157
return self._transport.abspath(self._escape(file_or_path))
103
@deprecated_method(zero_eight)
104
def controlfile(self, file_or_path, mode='r'):
105
"""Open a control file for this branch.
107
There are two classes of file in a lockable directory: text
108
and binary. binary files are untranslated byte streams. Text
109
control files are stored with Unix newlines and in UTF-8, even
110
if the platform or locale defaults are different.
112
Such files are not openable in write mode : they are managed via
113
put and put_utf8 which atomically replace old versions using
117
relpath = self._escape(file_or_path)
118
#TODO: codecs.open() buffers linewise, so it was overloaded with
119
# a much larger buffer, do we need to do the same for getreader/getwriter?
121
return self.get(relpath)
123
raise BzrError("Branch.controlfile(mode='wb') is not supported, use put[_utf8]")
125
return self.get_utf8(relpath)
127
raise BzrError("Branch.controlfile(mode='w') is not supported, use put[_utf8]")
129
raise BzrError("invalid controlfile mode %r" % mode)
160
@deprecated_method(deprecated_in((1, 5, 0)))
132
161
def get(self, relpath):
133
"""Get a file as a bytestream."""
162
"""Get a file as a bytestream.
164
:deprecated: Use a Transport instead of LockableFiles.
134
166
relpath = self._escape(relpath)
135
167
return self._transport.get(relpath)
170
@deprecated_method(deprecated_in((1, 5, 0)))
138
171
def get_utf8(self, relpath):
139
"""Get a file as a unicode stream."""
172
"""Get a file as a unicode stream.
174
:deprecated: Use a Transport instead of LockableFiles.
140
176
relpath = self._escape(relpath)
141
177
# DO NOT introduce an errors=replace here.
142
178
return codecs.getreader('utf-8')(self._transport.get(relpath))
144
180
@needs_write_lock
181
@deprecated_method(deprecated_in((1, 6, 0)))
145
182
def put(self, path, file):
148
185
:param path: The path to put the file, relative to the .bzr control
150
:param f: A file-like or string object whose contents should be copied.
152
self._transport.put(self._escape(path), file, mode=self._file_mode)
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)))
155
208
def put_utf8(self, path, a_string):
156
209
"""Write a string, encoding as utf-8.
158
211
:param path: The path to put the string, relative to the transport root.
159
:param string: A file-like or string object whose contents should be copied.
212
:param string: A string or unicode object whose contents should be copied.
214
:deprecated: Use Transport methods instead.
161
216
# IterableFile would not be needed if Transport.put took iterables
162
217
# instead of files. ADHB 2005-12-25
166
221
# these are valuable files which should have exact contents.
167
222
if not isinstance(a_string, basestring):
168
223
raise errors.BzrBadParameterNotString(a_string)
169
self.put(path, StringIO(a_string.encode('utf-8')))
171
def lock_write(self):
172
mutter("lock write: %s (%s)", self, self._lock_count)
224
self.put_bytes(path, a_string.encode('utf-8'))
226
def leave_in_place(self):
227
"""Set this LockableFiles to not clear the physical lock on unlock."""
228
self._lock.leave_in_place()
230
def dont_leave_in_place(self):
231
"""Set this LockableFiles to clear the physical lock on unlock."""
232
self._lock.dont_leave_in_place()
234
def lock_write(self, token=None):
235
"""Lock this group of files for writing.
237
:param token: if this is already locked, then lock_write will fail
238
unless the token matches the existing lock.
239
:returns: a token if this instance supports tokens, otherwise None.
240
:raises TokenLockingNotSupported: when a token is given but this
241
instance doesn't support using token locks.
242
:raises MismatchedToken: if the specified token doesn't match the token
243
of the existing lock.
245
A token should be passed in if you know that you have locked the object
246
some other way, and need to synchronise this object's state with that
173
249
# TODO: Upgrade locking to support using a Transport,
174
250
# and potentially a remote locking protocol
175
251
if self._lock_mode:
176
if self._lock_mode != 'w':
177
raise ReadOnlyError("can't upgrade to a write lock from %r" %
252
if self._lock_mode != 'w' or not self.get_transaction().writeable():
253
raise errors.ReadOnlyError(self)
254
self._lock.validate_token(token)
179
255
self._lock_count += 1
256
return self._token_from_lock
181
self._lock = self._transport.lock_write(
182
self._escape(self.lock_name))
258
token_from_lock = self._lock.lock_write(token=token)
259
#traceback.print_stack()
183
260
self._lock_mode = 'w'
184
261
self._lock_count = 1
185
self._set_transaction(transactions.PassThroughTransaction())
262
self._set_transaction(transactions.WriteTransaction())
263
self._token_from_lock = token_from_lock
264
return token_from_lock
187
266
def lock_read(self):
188
mutter("lock read: %s (%s)", self, self._lock_count)
189
267
if self._lock_mode:
190
assert self._lock_mode in ('r', 'w'), \
191
"invalid lock mode %r" % self._lock_mode
268
if self._lock_mode not in ('r', 'w'):
269
raise ValueError("invalid lock mode %r" % (self._lock_mode,))
192
270
self._lock_count += 1
194
self._lock = self._transport.lock_read(
195
self._escape(self.lock_name))
272
self._lock.lock_read()
273
#traceback.print_stack()
196
274
self._lock_mode = 'r'
197
275
self._lock_count = 1
198
276
self._set_transaction(transactions.ReadOnlyTransaction())
added
removed
bzrlib/lockable_files.py
