~bzr-pqm/bzr/bzr.dev

2052.3.2 by John Arbash Meinel
Change Copyright .. by Canonical to Copyright ... Canonical
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# Copyright (C) 2004, 2005 Canonical Ltd
1887.1.1 by Adeodato Simó
Do not separate paragraphs in the copyright statement with blank lines,
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#
409 by Martin Pool
- New AtomicFile class
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# This program is free software; you can redistribute it and/or modify
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# it under the terms of the GNU General Public License as published by
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# the Free Software Foundation; either version 2 of the License, or
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# (at your option) any later version.
1887.1.1 by Adeodato Simó
Do not separate paragraphs in the copyright statement with blank lines,
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#
409 by Martin Pool
- New AtomicFile class
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# This program is distributed in the hope that it will be useful,
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# but WITHOUT ANY WARRANTY; without even the implied warranty of
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
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# GNU General Public License for more details.
1887.1.1 by Adeodato Simó
Do not separate paragraphs in the copyright statement with blank lines,
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#
409 by Martin Pool
- New AtomicFile class
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# You should have received a copy of the GNU General Public License
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# along with this program; if not, write to the Free Software
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# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
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1773.4.1 by Martin Pool
Add pyflakes makefile target; fix many warnings
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import os
1996.3.15 by John Arbash Meinel
lazy_import AtomicFile
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import sys
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from bzrlib.lazy_import import lazy_import
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lazy_import(globals(), """
1755.3.6 by John Arbash Meinel
Add a test suite for Atomic File, and clean it up so that it really does set the mode properly.
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import stat
1755.3.1 by Robert Collins
Tune the time to build our kernel_like tree : make LocalTransport.put faster, AtomicFile faster, LocalTransport.append faster.
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import socket
1755.3.11 by John Arbash Meinel
Test that AtomicFile.closed is supported, but deprecated
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import warnings
1755.3.1 by Robert Collins
Tune the time to build our kernel_like tree : make LocalTransport.put faster, AtomicFile faster, LocalTransport.append faster.
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1755.3.6 by John Arbash Meinel
Add a test suite for Atomic File, and clean it up so that it really does set the mode properly.
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from bzrlib import (
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    errors,
1755.3.7 by John Arbash Meinel
Clean up and write tests for permissions. Now we use fstat which should be cheap, and lets us check the permissions and the file size
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    osutils,
1755.3.6 by John Arbash Meinel
Add a test suite for Atomic File, and clean it up so that it really does set the mode properly.
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    symbol_versioning,
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    )
1996.3.15 by John Arbash Meinel
lazy_import AtomicFile
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""")
1755.3.1 by Robert Collins
Tune the time to build our kernel_like tree : make LocalTransport.put faster, AtomicFile faster, LocalTransport.append faster.
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# not forksafe - but we dont fork.
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_pid = os.getpid()
1996.3.15 by John Arbash Meinel
lazy_import AtomicFile
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_hostname = None
1755.3.6 by John Arbash Meinel
Add a test suite for Atomic File, and clean it up so that it really does set the mode properly.
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563 by Martin Pool
- AtomicFile emits a warning if it is gc'd without being closed
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558 by Martin Pool
- All top-level classes inherit from object
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class AtomicFile(object):
409 by Martin Pool
- New AtomicFile class
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    """A file that does an atomic-rename to move into place.
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    This also causes hardlinks to break when it's written out.
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    Open this as for a regular file, then use commit() to move into
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    place or abort() to cancel.
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    """
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1755.3.9 by John Arbash Meinel
Make AtomicFile not do anything if not supplied a mode, clean up LocalTransport now that we do the right thing for None
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    __slots__ = ['tmpfilename', 'realfilename', '_fd']
1755.3.1 by Robert Collins
Tune the time to build our kernel_like tree : make LocalTransport.put faster, AtomicFile faster, LocalTransport.append faster.
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1755.3.9 by John Arbash Meinel
Make AtomicFile not do anything if not supplied a mode, clean up LocalTransport now that we do the right thing for None
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    def __init__(self, filename, mode='wb', new_mode=None):
1996.3.15 by John Arbash Meinel
lazy_import AtomicFile
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        global _hostname
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1755.3.6 by John Arbash Meinel
Add a test suite for Atomic File, and clean it up so that it really does set the mode properly.
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        self._fd = None
1755.3.1 by Robert Collins
Tune the time to build our kernel_like tree : make LocalTransport.put faster, AtomicFile faster, LocalTransport.append faster.
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1996.3.15 by John Arbash Meinel
lazy_import AtomicFile
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        if _hostname is None:
3626.1.1 by Mark Hammond
Add osutils.get_host_name() to return a unicode hostname to prevent
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            _hostname = osutils.get_host_name()
1996.3.15 by John Arbash Meinel
lazy_import AtomicFile
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1755.3.6 by John Arbash Meinel
Add a test suite for Atomic File, and clean it up so that it really does set the mode properly.
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        self.tmpfilename = '%s.%d.%s.tmp' % (filename, _pid, _hostname)
1755.3.4 by Robert Collins
current status
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409 by Martin Pool
- New AtomicFile class
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        self.realfilename = filename
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1755.3.6 by John Arbash Meinel
Add a test suite for Atomic File, and clean it up so that it really does set the mode properly.
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        flags = os.O_EXCL | os.O_CREAT | os.O_WRONLY
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        if mode == 'wb':
1755.3.7 by John Arbash Meinel
Clean up and write tests for permissions. Now we use fstat which should be cheap, and lets us check the permissions and the file size
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            flags |= osutils.O_BINARY
3376.2.4 by Martin Pool
Remove every assert statement from bzrlib!
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        elif mode != 'wt':
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            raise ValueError("invalid AtomicFile mode %r" % mode)
1755.3.9 by John Arbash Meinel
Make AtomicFile not do anything if not supplied a mode, clean up LocalTransport now that we do the right thing for None
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        if new_mode is not None:
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            local_mode = new_mode
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        else:
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            local_mode = 0666
1755.3.6 by John Arbash Meinel
Add a test suite for Atomic File, and clean it up so that it really does set the mode properly.
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1755.3.1 by Robert Collins
Tune the time to build our kernel_like tree : make LocalTransport.put faster, AtomicFile faster, LocalTransport.append faster.
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        # Use a low level fd operation to avoid chmodding later.
1755.3.6 by John Arbash Meinel
Add a test suite for Atomic File, and clean it up so that it really does set the mode properly.
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        # This may not succeed, but it should help most of the time
1755.3.9 by John Arbash Meinel
Make AtomicFile not do anything if not supplied a mode, clean up LocalTransport now that we do the right thing for None
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        self._fd = os.open(self.tmpfilename, flags, local_mode)
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        if new_mode is not None:
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            # Because of umask issues, we may need to chmod anyway
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            # the common case is that we won't, though.
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            st = os.fstat(self._fd)
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            if stat.S_IMODE(st.st_mode) != new_mode:
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                os.chmod(self.tmpfilename, new_mode)
1755.3.6 by John Arbash Meinel
Add a test suite for Atomic File, and clean it up so that it really does set the mode properly.
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    def _get_closed(self):
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        symbol_versioning.warn('AtomicFile.closed deprecated in bzr 0.10',
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                               DeprecationWarning, stacklevel=2)
1755.3.11 by John Arbash Meinel
Test that AtomicFile.closed is supported, but deprecated
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        return self._fd is None
1755.3.6 by John Arbash Meinel
Add a test suite for Atomic File, and clean it up so that it really does set the mode properly.
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    closed = property(_get_closed)
563 by Martin Pool
- AtomicFile emits a warning if it is gc'd without being closed
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    def __repr__(self):
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        return '%s(%r)' % (self.__class__.__name__,
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                           self.realfilename)
409 by Martin Pool
- New AtomicFile class
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1755.3.6 by John Arbash Meinel
Add a test suite for Atomic File, and clean it up so that it really does set the mode properly.
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    def write(self, data):
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        """Write some data to the file. Like file.write()"""
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        os.write(self._fd, data)
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    def _close_tmpfile(self, func_name):
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        """Close the local temp file in preparation for commit or abort"""
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        if self._fd is None:
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            raise errors.AtomicFileAlreadyClosed(path=self.realfilename,
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                                                 function=func_name)
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        fd = self._fd
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        self._fd = None
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        os.close(fd)
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409 by Martin Pool
- New AtomicFile class
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    def commit(self):
497 by Martin Pool
- new AtomicFile.close() aborts if appropriate
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        """Close the file and move to final name."""
1755.3.6 by John Arbash Meinel
Add a test suite for Atomic File, and clean it up so that it really does set the mode properly.
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        self._close_tmpfile('commit')
1996.3.15 by John Arbash Meinel
lazy_import AtomicFile
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        osutils.rename(self.tmpfilename, self.realfilename)
409 by Martin Pool
- New AtomicFile class
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    def abort(self):
497 by Martin Pool
- new AtomicFile.close() aborts if appropriate
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        """Discard temporary file without committing changes."""
1755.3.6 by John Arbash Meinel
Add a test suite for Atomic File, and clean it up so that it really does set the mode properly.
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        self._close_tmpfile('abort')
409 by Martin Pool
- New AtomicFile class
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        os.remove(self.tmpfilename)
497 by Martin Pool
- new AtomicFile.close() aborts if appropriate
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    def close(self):
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        """Discard the file unless already committed."""
1755.3.6 by John Arbash Meinel
Add a test suite for Atomic File, and clean it up so that it really does set the mode properly.
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        if self._fd is not None:
497 by Martin Pool
- new AtomicFile.close() aborts if appropriate
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            self.abort()
563 by Martin Pool
- AtomicFile emits a warning if it is gc'd without being closed
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    def __del__(self):
1755.3.6 by John Arbash Meinel
Add a test suite for Atomic File, and clean it up so that it really does set the mode properly.
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        if self._fd is not None:
1755.3.11 by John Arbash Meinel
Test that AtomicFile.closed is supported, but deprecated
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            warnings.warn("%r leaked" % self)