#! /usr/bin/python
# Copyright (C) 2005 Canonical Ltd
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
# XXX: Some consideration of the problems that might occur if there are
# files whose id differs only in case. That should probably be forbidden.
import errno
import os
from cStringIO import StringIO
import urllib
from bzrlib.weavefile import read_weave, write_weave_v5
from bzrlib.weave import Weave
from bzrlib.store import TransportStore, hash_prefix
from bzrlib.atomicfile import AtomicFile
from bzrlib.errors import NoSuchFile, FileExists
from bzrlib.trace import mutter
class WeaveStore(TransportStore):
"""Collection of several weave files in a directory.
This has some shortcuts for reading and writing them.
"""
FILE_SUFFIX = '.weave'
def __init__(self, transport, prefixed=False, precious=False,
dir_mode=None, file_mode=None):
super(WeaveStore, self).__init__(transport,
dir_mode=dir_mode, file_mode=file_mode,
prefixed=prefixed, compressed=False)
self._precious = precious
def filename(self, file_id):
"""Return the path relative to the transport root."""
if self._prefixed:
return hash_prefix(file_id) + urllib.quote(file_id) + WeaveStore.FILE_SUFFIX
else:
return urllib.quote(file_id) + WeaveStore.FILE_SUFFIX
def __iter__(self):
l = len(WeaveStore.FILE_SUFFIX)
for relpath in self._iter_files_recursive():
if relpath.endswith(WeaveStore.FILE_SUFFIX):
yield os.path.basename(relpath[:-l])
def has_id(self, fileid):
return self._transport.has(self.filename(fileid))
def _get(self, file_id):
return self._transport.get(self.filename(file_id))
def _put(self, file_id, f):
# less round trips to mkdir on failure than mkdir always
try:
return self._transport.put(self.filename(file_id), f, mode=self._file_mode)
except NoSuchFile:
if not self._prefixed:
raise
self._transport.mkdir(hash_prefix(file_id), mode=self._dir_mode)
return self._transport.put(self.filename(file_id), f, mode=self._file_mode)
def get_weave(self, file_id, transaction):
weave = transaction.map.find_weave(file_id)
if weave:
mutter("cache hit in %s for %s", self, file_id)
return weave
w = read_weave(self._get(file_id))
transaction.map.add_weave(file_id, w)
transaction.register_clean(w, precious=self._precious)
# TODO: jam 20051219 This should check if there is a prelude
# which is already cached, and if so, should remove it
# But transaction doesn't seem to have a 'remove'
# One workaround would be to re-add the object with
# the PRELUDE marker.
return w
def get_weave_prelude(self, file_id, transaction):
weave_id = file_id
weave = transaction.map.find_weave(weave_id)
if weave:
mutter("cache hit in %s for %s", self, weave_id)
return weave
# We want transactions to also cache preludes if that
# is all that we are loading. So we need a unique
# identifier, so that someone who wants the whole text
# won't get just the prelude
weave_id = 'PRELUDE-' + file_id
weave = transaction.map.find_weave(weave_id)
if weave:
mutter("cache hit in %s for %s", self, weave_id)
return weave
w = read_weave(self._get(file_id), prelude=True)
transaction.map.add_weave(weave_id, w)
transaction.register_clean(w, precious=self._precious)
return w
def get_lines(self, file_id, rev_id, transaction):
"""Return text from a particular version of a weave.
Returned as a list of lines."""
w = self.get_weave(file_id, transaction)
return w.get(w.lookup(rev_id))
def get_weave_prelude_or_empty(self, file_id, transaction):
"""cheap version that reads the prelude but not the lines
"""
try:
return self.get_weave_prelude(file_id, transaction)
except NoSuchFile:
# We can cache here, because we know that there
# is no complete object, since we got NoSuchFile
weave = Weave(weave_name=file_id)
transaction.map.add_weave(file_id, weave)
transaction.register_clean(weave, precious=self._precious)
return weave
def get_weave_or_empty(self, file_id, transaction):
"""Return a weave, or an empty one if it doesn't exist."""
try:
return self.get_weave(file_id, transaction)
except NoSuchFile:
weave = Weave(weave_name=file_id)
transaction.map.add_weave(file_id, weave)
transaction.register_clean(weave, precious=self._precious)
return weave
def put_weave(self, file_id, weave, transaction):
"""Write back a modified weave"""
transaction.register_dirty(weave)
# TODO FOR WRITE TRANSACTIONS: this should be done in a callback
# from the transaction, when it decides to save.
sio = StringIO()
write_weave_v5(weave, sio)
sio.seek(0)
self._put(file_id, sio)
def add_text(self, file_id, rev_id, new_lines, parents, transaction):
w = self.get_weave_or_empty(file_id, transaction)
parent_idxs = map(w.lookup, parents)
w.add(rev_id, parent_idxs, new_lines)
self.put_weave(file_id, w, transaction)
def add_identical_text(self, file_id, old_rev_id, new_rev_id, parents,
transaction):
w = self.get_weave_or_empty(file_id, transaction)
parent_idxs = map(w.lookup, parents)
w.add_identical(old_rev_id, new_rev_id, parent_idxs)
self.put_weave(file_id, w, transaction)
def copy_multi(self, from_store, file_ids, pb=None):
assert isinstance(from_store, WeaveStore)
for count, f in enumerate(file_ids):
mutter("copy weave {%s} into %s", f, self)
if pb:
pb.update('copy', count, len(file_ids))
self._put(f, from_store._get(f))
if pb:
pb.clear()