# Copyright (C) 2006 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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
"""MemoryTree object.
See MemoryTree for more details.
"""
import os
from bzrlib import (
errors,
mutabletree,
revision as _mod_revision,
)
from bzrlib.decorators import needs_read_lock
from bzrlib.osutils import sha_file
from bzrlib.mutabletree import needs_tree_write_lock
from bzrlib.transport.memory import MemoryTransport
class MemoryTree(mutabletree.MutableTree):
"""A MemoryTree is a specialisation of MutableTree.
It maintains nearly no state outside of read_lock and write_lock
transactions. (it keeps a reference to the branch, and its last-revision
only).
"""
def __init__(self, branch, revision_id):
"""Construct a MemoryTree for branch using revision_id."""
self.branch = branch
self.bzrdir = branch.bzrdir
self._branch_revision_id = revision_id
self._locks = 0
self._lock_mode = None
@needs_tree_write_lock
def _add(self, files, ids, kinds):
"""See MutableTree._add."""
for f, file_id, kind in zip(files, ids, kinds):
if kind is None:
kind = 'file'
if file_id is None:
self._inventory.add_path(f, kind=kind)
else:
self._inventory.add_path(f, kind=kind, file_id=file_id)
def basis_tree(self):
"""See Tree.basis_tree()."""
return self._basis_tree
@staticmethod
def create_on_branch(branch):
"""Create a MemoryTree for branch, using the last-revision of branch."""
revision_id = _mod_revision.ensure_null(branch.last_revision())
return MemoryTree(branch, revision_id)
def _gather_kinds(self, files, kinds):
"""See MutableTree._gather_kinds.
This implementation does not care about the file kind of
missing files, so is a no-op.
"""
def get_file(self, file_id, path=None):
"""See Tree.get_file."""
if path is None:
path = self.id2path(file_id)
return self._file_transport.get(path)
def get_file_sha1(self, file_id, path=None, stat_value=None):
"""See Tree.get_file_sha1()."""
if path is None:
path = self.id2path(file_id)
stream = self._file_transport.get(path)
return sha_file(stream)
def get_root_id(self):
return self.path2id('')
def _comparison_data(self, entry, path):
"""See Tree._comparison_data."""
if entry is None:
return None, False, None
return entry.kind, entry.executable, None
@needs_tree_write_lock
def rename_one(self, from_rel, to_rel):
file_id = self.path2id(from_rel)
to_dir, to_tail = os.path.split(to_rel)
to_parent_id = self.path2id(to_dir)
self._file_transport.move(from_rel, to_rel)
self._inventory.rename(file_id, to_parent_id, to_tail)
def path_content_summary(self, path):
"""See Tree.path_content_summary."""
id = self.path2id(path)
if id is None:
return 'missing', None, None, None
kind = self.kind(id)
if kind == 'file':
bytes = self._file_transport.get_bytes(path)
size = len(bytes)
executable = self._inventory[id].executable
sha1 = None # no stat cache
return (kind, size, executable, sha1)
elif kind == 'directory':
# memory tree does not support nested trees yet.
return kind, None, None, None
elif kind == 'symlink':
raise NotImplementedError('symlink support')
else:
raise NotImplementedError('unknown kind')
def _file_size(self, entry, stat_value):
"""See Tree._file_size."""
if entry is None:
return 0
return entry.text_size
@needs_read_lock
def get_parent_ids(self):
"""See Tree.get_parent_ids.
This implementation returns the current cached value from
self._parent_ids.
"""
return list(self._parent_ids)
def has_filename(self, filename):
"""See Tree.has_filename()."""
return self._file_transport.has(filename)
def is_executable(self, file_id, path=None):
return self._inventory[file_id].executable
def kind(self, file_id):
return self._inventory[file_id].kind
def mkdir(self, path, file_id=None):
"""See MutableTree.mkdir()."""
self.add(path, file_id, 'directory')
if file_id is None:
file_id = self.path2id(path)
self._file_transport.mkdir(path)
return file_id
@needs_read_lock
def last_revision(self):
"""See MutableTree.last_revision."""
return self._branch_revision_id
def lock_read(self):
"""Lock the memory tree for reading.
This triggers population of data from the branch for its revision.
"""
self._locks += 1
try:
if self._locks == 1:
self.branch.lock_read()
self._lock_mode = "r"
self._populate_from_branch()
except:
self._locks -= 1
raise
def lock_tree_write(self):
"""See MutableTree.lock_tree_write()."""
self._locks += 1
try:
if self._locks == 1:
self.branch.lock_read()
self._lock_mode = "w"
self._populate_from_branch()
elif self._lock_mode == "r":
raise errors.ReadOnlyError(self)
except:
self._locks -= 1
raise
def lock_write(self):
"""See MutableTree.lock_write()."""
self._locks += 1
try:
if self._locks == 1:
self.branch.lock_write()
self._lock_mode = "w"
self._populate_from_branch()
elif self._lock_mode == "r":
raise errors.ReadOnlyError(self)
except:
self._locks -= 1
raise
def _populate_from_branch(self):
"""Populate the in-tree state from the branch."""
self._set_basis()
if self._branch_revision_id == _mod_revision.NULL_REVISION:
self._parent_ids = []
else:
self._parent_ids = [self._branch_revision_id]
self._inventory = self._basis_tree._inventory._get_mutable_inventory()
self._file_transport = MemoryTransport()
# TODO copy the revision trees content, or do it lazy, or something.
inventory_entries = self._inventory.iter_entries()
for path, entry in inventory_entries:
if path == '':
continue
if entry.kind == 'directory':
self._file_transport.mkdir(path)
elif entry.kind == 'file':
self._file_transport.put_file(path,
self._basis_tree.get_file(entry.file_id))
else:
raise NotImplementedError(self._populate_from_branch)
def put_file_bytes_non_atomic(self, file_id, bytes):
"""See MutableTree.put_file_bytes_non_atomic."""
self._file_transport.put_bytes(self.id2path(file_id), bytes)
def unlock(self):
"""Release a lock.
This frees all cached state when the last lock context for the tree is
left.
"""
if self._locks == 1:
self._basis_tree = None
self._parent_ids = []
self._inventory = None
try:
self.branch.unlock()
finally:
self._locks = 0
self._lock_mode = None
else:
self._locks -= 1
@needs_tree_write_lock
def unversion(self, file_ids):
"""Remove the file ids in file_ids from the current versioned set.
When a file_id is unversioned, all of its children are automatically
unversioned.
:param file_ids: The file ids to stop versioning.
:raises: NoSuchId if any fileid is not currently versioned.
"""
# XXX: This should be in mutabletree, but the inventory-save action
# is not relevant to memory tree. Until that is done in unlock by
# working tree, we cannot share the implementation.
for file_id in file_ids:
if self._inventory.has_id(file_id):
self._inventory.remove_recursive_id(file_id)
else:
raise errors.NoSuchId(self, file_id)
def set_parent_ids(self, revision_ids, allow_leftmost_as_ghost=False):
"""See MutableTree.set_parent_trees()."""
for revision_id in revision_ids:
_mod_revision.check_not_reserved_id(revision_id)
if len(revision_ids) == 0:
self._parent_ids = []
self._branch_revision_id = _mod_revision.NULL_REVISION
else:
self._parent_ids = revision_ids
self._branch_revision_id = revision_ids[0]
self._allow_leftmost_as_ghost = allow_leftmost_as_ghost
self._set_basis()
def _set_basis(self):
try:
self._basis_tree = self.branch.repository.revision_tree(
self._branch_revision_id)
except errors.NoSuchRevision:
if self._allow_leftmost_as_ghost:
self._basis_tree = self.branch.repository.revision_tree(
_mod_revision.NULL_REVISION)
else:
raise
def set_parent_trees(self, parents_list, allow_leftmost_as_ghost=False):
"""See MutableTree.set_parent_trees()."""
if len(parents_list) == 0:
self._parent_ids = []
self._basis_tree = self.branch.repository.revision_tree(
_mod_revision.NULL_REVISION)
else:
if parents_list[0][1] is None and not allow_leftmost_as_ghost:
# a ghost in the left most parent
raise errors.GhostRevisionUnusableHere(parents_list[0][0])
self._parent_ids = [parent_id for parent_id, tree in parents_list]
if parents_list[0][1] is None or parents_list[0][1] == 'null:':
self._basis_tree = self.branch.repository.revision_tree(
_mod_revision.NULL_REVISION)
else:
self._basis_tree = parents_list[0][1]
self._branch_revision_id = parents_list[0][0]
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