Mercurial > hg
view mercurial/dirstatemap.py @ 50750:fa2eca7423f3 stable
Added signature for changeset 3ffc7209bbae
author | Raphaël Gomès <rgomes@octobus.net> |
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date | Thu, 06 Jul 2023 16:04:36 +0200 |
parents | bfbd84c57bda |
children | d718eddf01d9 |
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# dirstatemap.py # # This software may be used and distributed according to the terms of the # GNU General Public License version 2 or any later version. from .i18n import _ from . import ( error, pathutil, policy, testing, txnutil, util, ) from .dirstateutils import ( docket as docketmod, v2, ) parsers = policy.importmod('parsers') rustmod = policy.importrust('dirstate') propertycache = util.propertycache if rustmod is None: DirstateItem = parsers.DirstateItem else: DirstateItem = rustmod.DirstateItem rangemask = 0x7FFFFFFF WRITE_MODE_AUTO = 0 WRITE_MODE_FORCE_NEW = 1 WRITE_MODE_FORCE_APPEND = 2 V2_MAX_READ_ATTEMPTS = 5 class _dirstatemapcommon: """ Methods that are identical for both implementations of the dirstatemap class, with and without Rust extensions enabled. """ # please pytype _map = None copymap = None def __init__(self, ui, opener, root, nodeconstants, use_dirstate_v2): self._use_dirstate_v2 = use_dirstate_v2 self._nodeconstants = nodeconstants self._ui = ui self._opener = opener self._root = root self._filename = b'dirstate' self._nodelen = 20 # Also update Rust code when changing this! self._parents = None self._dirtyparents = False self._docket = None write_mode = ui.config(b"devel", b"dirstate.v2.data_update_mode") if write_mode == b"auto": self._write_mode = WRITE_MODE_AUTO elif write_mode == b"force-append": self._write_mode = WRITE_MODE_FORCE_APPEND elif write_mode == b"force-new": self._write_mode = WRITE_MODE_FORCE_NEW else: # unknown value, fallback to default self._write_mode = WRITE_MODE_AUTO # for consistent view between _pl() and _read() invocations self._pendingmode = None def _set_identity(self): self.identity = self._get_current_identity() def _get_current_identity(self): try: return util.cachestat(self._opener.join(self._filename)) except FileNotFoundError: return None def may_need_refresh(self): if 'identity' not in vars(self): # no existing identity, we need a refresh return True if self.identity is None: return True if not self.identity.cacheable(): # We cannot trust the entry # XXX this is a problem on windows, NFS, or other inode less system return True current_identity = self._get_current_identity() if current_identity is None: return True if not current_identity.cacheable(): # We cannot trust the entry # XXX this is a problem on windows, NFS, or other inode less system return True return current_identity != self.identity def preload(self): """Loads the underlying data, if it's not already loaded""" self._map def get(self, key, default=None): return self._map.get(key, default) def __len__(self): return len(self._map) def __iter__(self): return iter(self._map) def __contains__(self, key): return key in self._map def __getitem__(self, item): return self._map[item] ### disk interaction def _opendirstatefile(self): fp, mode = txnutil.trypending(self._root, self._opener, self._filename) if self._pendingmode is not None and self._pendingmode != mode: fp.close() raise error.Abort( _(b'working directory state may be changed parallelly') ) self._pendingmode = mode return fp def _readdirstatefile(self, size=-1): try: with self._opendirstatefile() as fp: return fp.read(size) except FileNotFoundError: # File doesn't exist, so the current state is empty return b'' @property def docket(self): if not self._docket: if not self._use_dirstate_v2: raise error.ProgrammingError( b'dirstate only has a docket in v2 format' ) self._set_identity() data = self._readdirstatefile() if data == b'' or data.startswith(docketmod.V2_FORMAT_MARKER): self._docket = docketmod.DirstateDocket.parse( data, self._nodeconstants ) else: raise error.CorruptedDirstate(b"dirstate is not in v2 format") return self._docket def _read_v2_data(self): data = None attempts = 0 while attempts < V2_MAX_READ_ATTEMPTS: attempts += 1 try: # TODO: use mmap when possible data = self._opener.read(self.docket.data_filename()) except FileNotFoundError: # read race detected between docket and data file # reload the docket and retry self._docket = None if data is None: assert attempts >= V2_MAX_READ_ATTEMPTS msg = b"dirstate read race happened %d times in a row" msg %= attempts raise error.Abort(msg) return self._opener.read(self.docket.data_filename()) def write_v2_no_append(self, tr, st, meta, packed): try: old_docket = self.docket except error.CorruptedDirstate: # This means we've identified a dirstate-v1 file on-disk when we # were expecting a dirstate-v2 docket. We've managed to recover # from that unexpected situation, and now we want to write back a # dirstate-v2 file to make the on-disk situation right again. # # This shouldn't be triggered since `self.docket` is cached and # we would have called parents() or read() first, but it's here # just in case. old_docket = None new_docket = docketmod.DirstateDocket.with_new_uuid( self.parents(), len(packed), meta ) if old_docket is not None and old_docket.uuid == new_docket.uuid: raise error.ProgrammingError(b'dirstate docket name collision') data_filename = new_docket.data_filename() self._opener.write(data_filename, packed) # tell the transaction that we are adding a new file if tr is not None: tr.addbackup(data_filename, location=b'plain') # Write the new docket after the new data file has been # written. Because `st` was opened with `atomictemp=True`, # the actual `.hg/dirstate` file is only affected on close. st.write(new_docket.serialize()) st.close() # Remove the old data file after the new docket pointing to # the new data file was written. if old_docket is not None and old_docket.uuid: data_filename = old_docket.data_filename() if tr is not None: tr.addbackup(data_filename, location=b'plain') unlink = lambda _tr=None: self._opener.unlink(data_filename) if tr: category = b"dirstate-v2-clean-" + old_docket.uuid tr.addpostclose(category, unlink) else: unlink() self._docket = new_docket ### reading/setting parents def parents(self): if not self._parents: if self._use_dirstate_v2: try: self.docket except error.CorruptedDirstate as e: # fall back to dirstate-v1 if we fail to read v2 self._v1_parents(e) else: self._parents = self.docket.parents else: self._v1_parents() return self._parents def _v1_parents(self, from_v2_exception=None): read_len = self._nodelen * 2 st = self._readdirstatefile(read_len) l = len(st) if l == read_len: self._parents = ( st[: self._nodelen], st[self._nodelen : 2 * self._nodelen], ) elif l == 0: self._parents = ( self._nodeconstants.nullid, self._nodeconstants.nullid, ) else: hint = None if from_v2_exception is not None: hint = _(b"falling back to dirstate-v1 from v2 also failed") raise error.Abort( _(b'working directory state appears damaged!'), hint ) class dirstatemap(_dirstatemapcommon): """Map encapsulating the dirstate's contents. The dirstate contains the following state: - `identity` is the identity of the dirstate file, which can be used to detect when changes have occurred to the dirstate file. - `parents` is a pair containing the parents of the working copy. The parents are updated by calling `setparents`. - the state map maps filenames to tuples of (state, mode, size, mtime), where state is a single character representing 'normal', 'added', 'removed', or 'merged'. It is read by treating the dirstate as a dict. File state is updated by calling various methods (see each documentation for details): - `reset_state`, - `set_tracked` - `set_untracked` - `set_clean` - `set_possibly_dirty` - `copymap` maps destination filenames to their source filename. The dirstate also provides the following views onto the state: - `filefoldmap` is a dict mapping normalized filenames to the denormalized form that they appear as in the dirstate. - `dirfoldmap` is a dict mapping normalized directory names to the denormalized form that they appear as in the dirstate. """ ### Core data storage and access @propertycache def _map(self): self._map = {} self.read() return self._map @propertycache def copymap(self): self.copymap = {} self._map return self.copymap def clear(self): self._map.clear() self.copymap.clear() self.setparents(self._nodeconstants.nullid, self._nodeconstants.nullid) util.clearcachedproperty(self, b"_dirs") util.clearcachedproperty(self, b"_alldirs") util.clearcachedproperty(self, b"filefoldmap") util.clearcachedproperty(self, b"dirfoldmap") def items(self): return self._map.items() # forward for python2,3 compat iteritems = items def debug_iter(self, all): """ Return an iterator of (filename, state, mode, size, mtime) tuples `all` is unused when Rust is not enabled """ for (filename, item) in self.items(): yield (filename, item.state, item.mode, item.size, item.mtime) def keys(self): return self._map.keys() ### reading/setting parents def setparents(self, p1, p2, fold_p2=False): self._parents = (p1, p2) self._dirtyparents = True copies = {} if fold_p2: for f, s in self._map.items(): # Discard "merged" markers when moving away from a merge state if s.p2_info: source = self.copymap.pop(f, None) if source: copies[f] = source s.drop_merge_data() return copies ### disk interaction def read(self): testing.wait_on_cfg(self._ui, b'dirstate.pre-read-file') if self._use_dirstate_v2: try: self.docket except error.CorruptedDirstate: # fall back to dirstate-v1 if we fail to read v2 self._set_identity() st = self._readdirstatefile() else: if not self.docket.uuid: return testing.wait_on_cfg(self._ui, b'dirstate.post-docket-read-file') st = self._read_v2_data() else: self._set_identity() st = self._readdirstatefile() if not st: return # TODO: adjust this estimate for dirstate-v2 if util.safehasattr(parsers, 'dict_new_presized'): # Make an estimate of the number of files in the dirstate based on # its size. This trades wasting some memory for avoiding costly # resizes. Each entry have a prefix of 17 bytes followed by one or # two path names. Studies on various large-scale real-world repositories # found 54 bytes a reasonable upper limit for the average path names. # Copy entries are ignored for the sake of this estimate. self._map = parsers.dict_new_presized(len(st) // 71) # Python's garbage collector triggers a GC each time a certain number # of container objects (the number being defined by # gc.get_threshold()) are allocated. parse_dirstate creates a tuple # for each file in the dirstate. The C version then immediately marks # them as not to be tracked by the collector. However, this has no # effect on when GCs are triggered, only on what objects the GC looks # into. This means that O(number of files) GCs are unavoidable. # Depending on when in the process's lifetime the dirstate is parsed, # this can get very expensive. As a workaround, disable GC while # parsing the dirstate. # # (we cannot decorate the function directly since it is in a C module) if self._use_dirstate_v2: try: self.docket except error.CorruptedDirstate: # fall back to dirstate-v1 if we fail to parse v2 parse_dirstate = util.nogc(parsers.parse_dirstate) p = parse_dirstate(self._map, self.copymap, st) else: p = self.docket.parents meta = self.docket.tree_metadata parse_dirstate = util.nogc(v2.parse_dirstate) parse_dirstate(self._map, self.copymap, st, meta) else: parse_dirstate = util.nogc(parsers.parse_dirstate) p = parse_dirstate(self._map, self.copymap, st) if not self._dirtyparents: self.setparents(*p) # Avoid excess attribute lookups by fast pathing certain checks self.__contains__ = self._map.__contains__ self.__getitem__ = self._map.__getitem__ self.get = self._map.get def write(self, tr, st): if self._use_dirstate_v2: packed, meta = v2.pack_dirstate(self._map, self.copymap) self.write_v2_no_append(tr, st, meta, packed) else: packed = parsers.pack_dirstate( self._map, self.copymap, self.parents() ) st.write(packed) st.close() self._dirtyparents = False @propertycache def identity(self): self._map return self.identity ### code related to maintaining and accessing "extra" property # (e.g. "has_dir") def _dirs_incr(self, filename, old_entry=None): """increment the dirstate counter if applicable""" if ( old_entry is None or old_entry.removed ) and "_dirs" in self.__dict__: self._dirs.addpath(filename) if old_entry is None and "_alldirs" in self.__dict__: self._alldirs.addpath(filename) def _dirs_decr(self, filename, old_entry=None, remove_variant=False): """decrement the dirstate counter if applicable""" if old_entry is not None: if "_dirs" in self.__dict__ and not old_entry.removed: self._dirs.delpath(filename) if "_alldirs" in self.__dict__ and not remove_variant: self._alldirs.delpath(filename) elif remove_variant and "_alldirs" in self.__dict__: self._alldirs.addpath(filename) if "filefoldmap" in self.__dict__: normed = util.normcase(filename) self.filefoldmap.pop(normed, None) @propertycache def filefoldmap(self): """Returns a dictionary mapping normalized case paths to their non-normalized versions. """ try: makefilefoldmap = parsers.make_file_foldmap except AttributeError: pass else: return makefilefoldmap( self._map, util.normcasespec, util.normcasefallback ) f = {} normcase = util.normcase for name, s in self._map.items(): if not s.removed: f[normcase(name)] = name f[b'.'] = b'.' # prevents useless util.fspath() invocation return f @propertycache def dirfoldmap(self): f = {} normcase = util.normcase for name in self._dirs: f[normcase(name)] = name return f def hastrackeddir(self, d): """ Returns True if the dirstate contains a tracked (not removed) file in this directory. """ return d in self._dirs def hasdir(self, d): """ Returns True if the dirstate contains a file (tracked or removed) in this directory. """ return d in self._alldirs @propertycache def _dirs(self): return pathutil.dirs(self._map, only_tracked=True) @propertycache def _alldirs(self): return pathutil.dirs(self._map) ### code related to manipulation of entries and copy-sources def reset_state( self, filename, wc_tracked=False, p1_tracked=False, p2_info=False, has_meaningful_mtime=True, parentfiledata=None, ): """Set a entry to a given state, diregarding all previous state This is to be used by the part of the dirstate API dedicated to adjusting the dirstate after a update/merge. note: calling this might result to no entry existing at all if the dirstate map does not see any point at having one for this file anymore. """ # copy information are now outdated # (maybe new information should be in directly passed to this function) self.copymap.pop(filename, None) if not (p1_tracked or p2_info or wc_tracked): old_entry = self._map.get(filename) self._drop_entry(filename) self._dirs_decr(filename, old_entry=old_entry) return old_entry = self._map.get(filename) self._dirs_incr(filename, old_entry) entry = DirstateItem( wc_tracked=wc_tracked, p1_tracked=p1_tracked, p2_info=p2_info, has_meaningful_mtime=has_meaningful_mtime, parentfiledata=parentfiledata, ) self._map[filename] = entry def set_tracked(self, filename): new = False entry = self.get(filename) if entry is None: self._dirs_incr(filename) entry = DirstateItem( wc_tracked=True, ) self._map[filename] = entry new = True elif not entry.tracked: self._dirs_incr(filename, entry) entry.set_tracked() self._refresh_entry(filename, entry) new = True else: # XXX This is probably overkill for more case, but we need this to # fully replace the `normallookup` call with `set_tracked` one. # Consider smoothing this in the future. entry.set_possibly_dirty() self._refresh_entry(filename, entry) return new def set_untracked(self, f): """Mark a file as no longer tracked in the dirstate map""" entry = self.get(f) if entry is None: return False else: self._dirs_decr(f, old_entry=entry, remove_variant=not entry.added) if not entry.p2_info: self.copymap.pop(f, None) entry.set_untracked() self._refresh_entry(f, entry) return True def set_clean(self, filename, mode, size, mtime): """mark a file as back to a clean state""" entry = self[filename] size = size & rangemask entry.set_clean(mode, size, mtime) self._refresh_entry(filename, entry) self.copymap.pop(filename, None) def set_possibly_dirty(self, filename): """record that the current state of the file on disk is unknown""" entry = self[filename] entry.set_possibly_dirty() self._refresh_entry(filename, entry) def _refresh_entry(self, f, entry): """record updated state of an entry""" if not entry.any_tracked: self._map.pop(f, None) def _drop_entry(self, f): """remove any entry for file f This should also drop associated copy information The fact we actually need to drop it is the responsability of the caller""" self._map.pop(f, None) self.copymap.pop(f, None) if rustmod is not None: class dirstatemap(_dirstatemapcommon): ### Core data storage and access @propertycache def _map(self): """ Fills the Dirstatemap when called. """ # ignore HG_PENDING because identity is used only for writing self._set_identity() testing.wait_on_cfg(self._ui, b'dirstate.pre-read-file') if self._use_dirstate_v2: try: self.docket except error.CorruptedDirstate as e: # fall back to dirstate-v1 if we fail to read v2 parents = self._v1_map(e) else: parents = self.docket.parents inode = ( self.identity.stat.st_ino if self.identity is not None and self.identity.stat is not None else None ) testing.wait_on_cfg( self._ui, b'dirstate.post-docket-read-file' ) if not self.docket.uuid: data = b'' self._map = rustmod.DirstateMap.new_empty() else: data = self._read_v2_data() self._map = rustmod.DirstateMap.new_v2( data, self.docket.data_size, self.docket.tree_metadata, self.docket.uuid, inode, ) parents = self.docket.parents else: parents = self._v1_map() if parents and not self._dirtyparents: self.setparents(*parents) self.__contains__ = self._map.__contains__ self.__getitem__ = self._map.__getitem__ self.get = self._map.get return self._map def _v1_map(self, from_v2_exception=None): self._set_identity() inode = ( self.identity.stat.st_ino if self.identity is not None and self.identity.stat is not None else None ) try: self._map, parents = rustmod.DirstateMap.new_v1( self._readdirstatefile(), inode ) except OSError as e: if from_v2_exception is not None: raise e from from_v2_exception raise return parents @property def copymap(self): return self._map.copymap() def debug_iter(self, all): """ Return an iterator of (filename, state, mode, size, mtime) tuples `all`: also include with `state == b' '` dirstate tree nodes that don't have an associated `DirstateItem`. """ return self._map.debug_iter(all) def clear(self): self._map.clear() self.setparents( self._nodeconstants.nullid, self._nodeconstants.nullid ) util.clearcachedproperty(self, b"_dirs") util.clearcachedproperty(self, b"_alldirs") util.clearcachedproperty(self, b"dirfoldmap") def items(self): return self._map.items() # forward for python2,3 compat iteritems = items def keys(self): return iter(self._map) ### reading/setting parents def setparents(self, p1, p2, fold_p2=False): self._parents = (p1, p2) self._dirtyparents = True copies = {} if fold_p2: copies = self._map.setparents_fixup() return copies ### disk interaction @propertycache def identity(self): self._map return self.identity def write(self, tr, st): if not self._use_dirstate_v2: p1, p2 = self.parents() packed = self._map.write_v1(p1, p2) st.write(packed) st.close() self._dirtyparents = False return write_mode = self._write_mode try: docket = self.docket except error.CorruptedDirstate: # fall back to dirstate-v1 if we fail to parse v2 docket = None # We can only append to an existing data file if there is one if docket is None or docket.uuid is None: write_mode = WRITE_MODE_FORCE_NEW packed, meta, append = self._map.write_v2(write_mode) if append: docket = self.docket data_filename = docket.data_filename() # We mark it for backup to make sure a future `hg rollback` (or # `hg recover`?) call find the data it needs to restore a # working repository. # # The backup can use a hardlink because the format is resistant # to trailing "dead" data. if tr is not None: tr.addbackup(data_filename, location=b'plain') with self._opener(data_filename, b'r+b') as fp: fp.seek(docket.data_size) assert fp.tell() == docket.data_size written = fp.write(packed) if written is not None: # py2 may return None assert written == len(packed), (written, len(packed)) docket.data_size += len(packed) docket.parents = self.parents() docket.tree_metadata = meta st.write(docket.serialize()) st.close() else: self.write_v2_no_append(tr, st, meta, packed) # Reload from the newly-written file util.clearcachedproperty(self, b"_map") self._dirtyparents = False ### code related to maintaining and accessing "extra" property # (e.g. "has_dir") @propertycache def filefoldmap(self): """Returns a dictionary mapping normalized case paths to their non-normalized versions. """ return self._map.filefoldmapasdict() def hastrackeddir(self, d): return self._map.hastrackeddir(d) def hasdir(self, d): return self._map.hasdir(d) @propertycache def dirfoldmap(self): f = {} normcase = util.normcase for name in self._map.tracked_dirs(): f[normcase(name)] = name return f ### code related to manipulation of entries and copy-sources def set_tracked(self, f): return self._map.set_tracked(f) def set_untracked(self, f): return self._map.set_untracked(f) def set_clean(self, filename, mode, size, mtime): self._map.set_clean(filename, mode, size, mtime) def set_possibly_dirty(self, f): self._map.set_possibly_dirty(f) def reset_state( self, filename, wc_tracked=False, p1_tracked=False, p2_info=False, has_meaningful_mtime=True, parentfiledata=None, ): return self._map.reset_state( filename, wc_tracked, p1_tracked, p2_info, has_meaningful_mtime, parentfiledata, )