dirstate: add begin/endparentchange to dirstate
It's possible for the dirstate to become incoherent (issue4353) if there is an
exception in the middle of the dirstate parent and entries being written (like
if the user ctrl+c's). This change adds begin/endparentchange which a future
patch will require to be set before changing the dirstate parent. This will
allow us to prevent writing the dirstate in the event of an exception while
changing the parent.
# dirstate.py - working directory tracking for mercurial
#
# Copyright 2005-2007 Matt Mackall <mpm@selenic.com>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
from node import nullid
from i18n import _
import scmutil, util, ignore, osutil, parsers, encoding, pathutil
import os, stat, errno, gc
propertycache = util.propertycache
filecache = scmutil.filecache
_rangemask = 0x7fffffff
dirstatetuple = parsers.dirstatetuple
class repocache(filecache):
"""filecache for files in .hg/"""
def join(self, obj, fname):
return obj._opener.join(fname)
class rootcache(filecache):
"""filecache for files in the repository root"""
def join(self, obj, fname):
return obj._join(fname)
class dirstate(object):
def __init__(self, opener, ui, root, validate):
'''Create a new dirstate object.
opener is an open()-like callable that can be used to open the
dirstate file; root is the root of the directory tracked by
the dirstate.
'''
self._opener = opener
self._validate = validate
self._root = root
self._rootdir = os.path.join(root, '')
self._dirty = False
self._dirtypl = False
self._lastnormaltime = 0
self._ui = ui
self._filecache = {}
self._parentwriters = 0
def beginparentchange(self):
'''Marks the beginning of a set of changes that involve changing
the dirstate parents. If there is an exception during this time,
the dirstate will not be written when the wlock is released. This
prevents writing an incoherent dirstate where the parent doesn't
match the contents.
'''
self._parentwriters += 1
def endparentchange(self):
'''Marks the end of a set of changes that involve changing the
dirstate parents. Once all parent changes have been marked done,
the wlock will be free to write the dirstate on release.
'''
if self._parentwriters > 0:
self._parentwriters -= 1
def pendingparentchange(self):
'''Returns true if the dirstate is in the middle of a set of changes
that modify the dirstate parent.
'''
return self._parentwriters > 0
@propertycache
def _map(self):
'''Return the dirstate contents as a map from filename to
(state, mode, size, time).'''
self._read()
return self._map
@propertycache
def _copymap(self):
self._read()
return self._copymap
@propertycache
def _foldmap(self):
f = {}
for name, s in self._map.iteritems():
if s[0] != 'r':
f[util.normcase(name)] = name
for name in self._dirs:
f[util.normcase(name)] = name
f['.'] = '.' # prevents useless util.fspath() invocation
return f
@repocache('branch')
def _branch(self):
try:
return self._opener.read("branch").strip() or "default"
except IOError, inst:
if inst.errno != errno.ENOENT:
raise
return "default"
@propertycache
def _pl(self):
try:
fp = self._opener("dirstate")
st = fp.read(40)
fp.close()
l = len(st)
if l == 40:
return st[:20], st[20:40]
elif l > 0 and l < 40:
raise util.Abort(_('working directory state appears damaged!'))
except IOError, err:
if err.errno != errno.ENOENT:
raise
return [nullid, nullid]
@propertycache
def _dirs(self):
return scmutil.dirs(self._map, 'r')
def dirs(self):
return self._dirs
@rootcache('.hgignore')
def _ignore(self):
files = [self._join('.hgignore')]
for name, path in self._ui.configitems("ui"):
if name == 'ignore' or name.startswith('ignore.'):
files.append(util.expandpath(path))
return ignore.ignore(self._root, files, self._ui.warn)
@propertycache
def _slash(self):
return self._ui.configbool('ui', 'slash') and os.sep != '/'
@propertycache
def _checklink(self):
return util.checklink(self._root)
@propertycache
def _checkexec(self):
return util.checkexec(self._root)
@propertycache
def _checkcase(self):
return not util.checkcase(self._join('.hg'))
def _join(self, f):
# much faster than os.path.join()
# it's safe because f is always a relative path
return self._rootdir + f
def flagfunc(self, buildfallback):
if self._checklink and self._checkexec:
def f(x):
try:
st = os.lstat(self._join(x))
if util.statislink(st):
return 'l'
if util.statisexec(st):
return 'x'
except OSError:
pass
return ''
return f
fallback = buildfallback()
if self._checklink:
def f(x):
if os.path.islink(self._join(x)):
return 'l'
if 'x' in fallback(x):
return 'x'
return ''
return f
if self._checkexec:
def f(x):
if 'l' in fallback(x):
return 'l'
if util.isexec(self._join(x)):
return 'x'
return ''
return f
else:
return fallback
@propertycache
def _cwd(self):
return os.getcwd()
def getcwd(self):
cwd = self._cwd
if cwd == self._root:
return ''
# self._root ends with a path separator if self._root is '/' or 'C:\'
rootsep = self._root
if not util.endswithsep(rootsep):
rootsep += os.sep
if cwd.startswith(rootsep):
return cwd[len(rootsep):]
else:
# we're outside the repo. return an absolute path.
return cwd
def pathto(self, f, cwd=None):
if cwd is None:
cwd = self.getcwd()
path = util.pathto(self._root, cwd, f)
if self._slash:
return util.pconvert(path)
return path
def __getitem__(self, key):
'''Return the current state of key (a filename) in the dirstate.
States are:
n normal
m needs merging
r marked for removal
a marked for addition
? not tracked
'''
return self._map.get(key, ("?",))[0]
def __contains__(self, key):
return key in self._map
def __iter__(self):
for x in sorted(self._map):
yield x
def iteritems(self):
return self._map.iteritems()
def parents(self):
return [self._validate(p) for p in self._pl]
def p1(self):
return self._validate(self._pl[0])
def p2(self):
return self._validate(self._pl[1])
def branch(self):
return encoding.tolocal(self._branch)
def setparents(self, p1, p2=nullid):
"""Set dirstate parents to p1 and p2.
When moving from two parents to one, 'm' merged entries a
adjusted to normal and previous copy records discarded and
returned by the call.
See localrepo.setparents()
"""
self._dirty = self._dirtypl = True
oldp2 = self._pl[1]
self._pl = p1, p2
copies = {}
if oldp2 != nullid and p2 == nullid:
# Discard 'm' markers when moving away from a merge state
for f, s in self._map.iteritems():
if s[0] == 'm':
if f in self._copymap:
copies[f] = self._copymap[f]
self.normallookup(f)
return copies
def setbranch(self, branch):
self._branch = encoding.fromlocal(branch)
f = self._opener('branch', 'w', atomictemp=True)
try:
f.write(self._branch + '\n')
f.close()
# make sure filecache has the correct stat info for _branch after
# replacing the underlying file
ce = self._filecache['_branch']
if ce:
ce.refresh()
except: # re-raises
f.discard()
raise
def _read(self):
self._map = {}
self._copymap = {}
try:
st = self._opener.read("dirstate")
except IOError, err:
if err.errno != errno.ENOENT:
raise
return
if not st:
return
# 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.
gcenabled = gc.isenabled()
gc.disable()
try:
p = parsers.parse_dirstate(self._map, self._copymap, st)
finally:
if gcenabled:
gc.enable()
if not self._dirtypl:
self._pl = p
def invalidate(self):
for a in ("_map", "_copymap", "_foldmap", "_branch", "_pl", "_dirs",
"_ignore"):
if a in self.__dict__:
delattr(self, a)
self._lastnormaltime = 0
self._dirty = False
self._parentwriters = 0
def copy(self, source, dest):
"""Mark dest as a copy of source. Unmark dest if source is None."""
if source == dest:
return
self._dirty = True
if source is not None:
self._copymap[dest] = source
elif dest in self._copymap:
del self._copymap[dest]
def copied(self, file):
return self._copymap.get(file, None)
def copies(self):
return self._copymap
def _droppath(self, f):
if self[f] not in "?r" and "_dirs" in self.__dict__:
self._dirs.delpath(f)
def _addpath(self, f, state, mode, size, mtime):
oldstate = self[f]
if state == 'a' or oldstate == 'r':
scmutil.checkfilename(f)
if f in self._dirs:
raise util.Abort(_('directory %r already in dirstate') % f)
# shadows
for d in scmutil.finddirs(f):
if d in self._dirs:
break
if d in self._map and self[d] != 'r':
raise util.Abort(
_('file %r in dirstate clashes with %r') % (d, f))
if oldstate in "?r" and "_dirs" in self.__dict__:
self._dirs.addpath(f)
self._dirty = True
self._map[f] = dirstatetuple(state, mode, size, mtime)
def normal(self, f):
'''Mark a file normal and clean.'''
s = os.lstat(self._join(f))
mtime = int(s.st_mtime)
self._addpath(f, 'n', s.st_mode,
s.st_size & _rangemask, mtime & _rangemask)
if f in self._copymap:
del self._copymap[f]
if mtime > self._lastnormaltime:
# Remember the most recent modification timeslot for status(),
# to make sure we won't miss future size-preserving file content
# modifications that happen within the same timeslot.
self._lastnormaltime = mtime
def normallookup(self, f):
'''Mark a file normal, but possibly dirty.'''
if self._pl[1] != nullid and f in self._map:
# if there is a merge going on and the file was either
# in state 'm' (-1) or coming from other parent (-2) before
# being removed, restore that state.
entry = self._map[f]
if entry[0] == 'r' and entry[2] in (-1, -2):
source = self._copymap.get(f)
if entry[2] == -1:
self.merge(f)
elif entry[2] == -2:
self.otherparent(f)
if source:
self.copy(source, f)
return
if entry[0] == 'm' or entry[0] == 'n' and entry[2] == -2:
return
self._addpath(f, 'n', 0, -1, -1)
if f in self._copymap:
del self._copymap[f]
def otherparent(self, f):
'''Mark as coming from the other parent, always dirty.'''
if self._pl[1] == nullid:
raise util.Abort(_("setting %r to other parent "
"only allowed in merges") % f)
self._addpath(f, 'n', 0, -2, -1)
if f in self._copymap:
del self._copymap[f]
def add(self, f):
'''Mark a file added.'''
self._addpath(f, 'a', 0, -1, -1)
if f in self._copymap:
del self._copymap[f]
def remove(self, f):
'''Mark a file removed.'''
self._dirty = True
self._droppath(f)
size = 0
if self._pl[1] != nullid and f in self._map:
# backup the previous state
entry = self._map[f]
if entry[0] == 'm': # merge
size = -1
elif entry[0] == 'n' and entry[2] == -2: # other parent
size = -2
self._map[f] = dirstatetuple('r', 0, size, 0)
if size == 0 and f in self._copymap:
del self._copymap[f]
def merge(self, f):
'''Mark a file merged.'''
if self._pl[1] == nullid:
return self.normallookup(f)
s = os.lstat(self._join(f))
self._addpath(f, 'm', s.st_mode,
s.st_size & _rangemask, int(s.st_mtime) & _rangemask)
if f in self._copymap:
del self._copymap[f]
def drop(self, f):
'''Drop a file from the dirstate'''
if f in self._map:
self._dirty = True
self._droppath(f)
del self._map[f]
def _normalize(self, path, isknown, ignoremissing=False, exists=None):
normed = util.normcase(path)
folded = self._foldmap.get(normed, None)
if folded is None:
if isknown:
folded = path
else:
if exists is None:
exists = os.path.lexists(os.path.join(self._root, path))
if not exists:
# Maybe a path component exists
if not ignoremissing and '/' in path:
d, f = path.rsplit('/', 1)
d = self._normalize(d, isknown, ignoremissing, None)
folded = d + "/" + f
else:
# No path components, preserve original case
folded = path
else:
# recursively normalize leading directory components
# against dirstate
if '/' in normed:
d, f = normed.rsplit('/', 1)
d = self._normalize(d, isknown, ignoremissing, True)
r = self._root + "/" + d
folded = d + "/" + util.fspath(f, r)
else:
folded = util.fspath(normed, self._root)
self._foldmap[normed] = folded
return folded
def normalize(self, path, isknown=False, ignoremissing=False):
'''
normalize the case of a pathname when on a casefolding filesystem
isknown specifies whether the filename came from walking the
disk, to avoid extra filesystem access.
If ignoremissing is True, missing path are returned
unchanged. Otherwise, we try harder to normalize possibly
existing path components.
The normalized case is determined based on the following precedence:
- version of name already stored in the dirstate
- version of name stored on disk
- version provided via command arguments
'''
if self._checkcase:
return self._normalize(path, isknown, ignoremissing)
return path
def clear(self):
self._map = {}
if "_dirs" in self.__dict__:
delattr(self, "_dirs")
self._copymap = {}
self._pl = [nullid, nullid]
self._lastnormaltime = 0
self._dirty = True
def rebuild(self, parent, allfiles, changedfiles=None):
changedfiles = changedfiles or allfiles
oldmap = self._map
self.clear()
for f in allfiles:
if f not in changedfiles:
self._map[f] = oldmap[f]
else:
if 'x' in allfiles.flags(f):
self._map[f] = dirstatetuple('n', 0777, -1, 0)
else:
self._map[f] = dirstatetuple('n', 0666, -1, 0)
self._pl = (parent, nullid)
self._dirty = True
def write(self):
if not self._dirty:
return
# enough 'delaywrite' prevents 'pack_dirstate' from dropping
# timestamp of each entries in dirstate, because of 'now > mtime'
delaywrite = self._ui.configint('debug', 'dirstate.delaywrite', 0)
if delaywrite:
import time # to avoid useless import
time.sleep(delaywrite)
st = self._opener("dirstate", "w", atomictemp=True)
# use the modification time of the newly created temporary file as the
# filesystem's notion of 'now'
now = util.fstat(st).st_mtime
st.write(parsers.pack_dirstate(self._map, self._copymap, self._pl, now))
st.close()
self._lastnormaltime = 0
self._dirty = self._dirtypl = False
def _dirignore(self, f):
if f == '.':
return False
if self._ignore(f):
return True
for p in scmutil.finddirs(f):
if self._ignore(p):
return True
return False
def _walkexplicit(self, match, subrepos):
'''Get stat data about the files explicitly specified by match.
Return a triple (results, dirsfound, dirsnotfound).
- results is a mapping from filename to stat result. It also contains
listings mapping subrepos and .hg to None.
- dirsfound is a list of files found to be directories.
- dirsnotfound is a list of files that the dirstate thinks are
directories and that were not found.'''
def badtype(mode):
kind = _('unknown')
if stat.S_ISCHR(mode):
kind = _('character device')
elif stat.S_ISBLK(mode):
kind = _('block device')
elif stat.S_ISFIFO(mode):
kind = _('fifo')
elif stat.S_ISSOCK(mode):
kind = _('socket')
elif stat.S_ISDIR(mode):
kind = _('directory')
return _('unsupported file type (type is %s)') % kind
matchedir = match.explicitdir
badfn = match.bad
dmap = self._map
normpath = util.normpath
lstat = os.lstat
getkind = stat.S_IFMT
dirkind = stat.S_IFDIR
regkind = stat.S_IFREG
lnkkind = stat.S_IFLNK
join = self._join
dirsfound = []
foundadd = dirsfound.append
dirsnotfound = []
notfoundadd = dirsnotfound.append
if match.matchfn != match.exact and self._checkcase:
normalize = self._normalize
else:
normalize = None
files = sorted(match.files())
subrepos.sort()
i, j = 0, 0
while i < len(files) and j < len(subrepos):
subpath = subrepos[j] + "/"
if files[i] < subpath:
i += 1
continue
while i < len(files) and files[i].startswith(subpath):
del files[i]
j += 1
if not files or '.' in files:
files = ['']
results = dict.fromkeys(subrepos)
results['.hg'] = None
for ff in files:
if normalize:
nf = normalize(normpath(ff), False, True)
else:
nf = normpath(ff)
if nf in results:
continue
try:
st = lstat(join(nf))
kind = getkind(st.st_mode)
if kind == dirkind:
if nf in dmap:
# file replaced by dir on disk but still in dirstate
results[nf] = None
if matchedir:
matchedir(nf)
foundadd(nf)
elif kind == regkind or kind == lnkkind:
results[nf] = st
else:
badfn(ff, badtype(kind))
if nf in dmap:
results[nf] = None
except OSError, inst: # nf not found on disk - it is dirstate only
if nf in dmap: # does it exactly match a missing file?
results[nf] = None
else: # does it match a missing directory?
prefix = nf + "/"
for fn in dmap:
if fn.startswith(prefix):
if matchedir:
matchedir(nf)
notfoundadd(nf)
break
else:
badfn(ff, inst.strerror)
return results, dirsfound, dirsnotfound
def walk(self, match, subrepos, unknown, ignored, full=True):
'''
Walk recursively through the directory tree, finding all files
matched by match.
If full is False, maybe skip some known-clean files.
Return a dict mapping filename to stat-like object (either
mercurial.osutil.stat instance or return value of os.stat()).
'''
# full is a flag that extensions that hook into walk can use -- this
# implementation doesn't use it at all. This satisfies the contract
# because we only guarantee a "maybe".
if ignored:
ignore = util.never
dirignore = util.never
elif unknown:
ignore = self._ignore
dirignore = self._dirignore
else:
# if not unknown and not ignored, drop dir recursion and step 2
ignore = util.always
dirignore = util.always
matchfn = match.matchfn
matchalways = match.always()
matchtdir = match.traversedir
dmap = self._map
listdir = osutil.listdir
lstat = os.lstat
dirkind = stat.S_IFDIR
regkind = stat.S_IFREG
lnkkind = stat.S_IFLNK
join = self._join
exact = skipstep3 = False
if matchfn == match.exact: # match.exact
exact = True
dirignore = util.always # skip step 2
elif match.files() and not match.anypats(): # match.match, no patterns
skipstep3 = True
if not exact and self._checkcase:
normalize = self._normalize
skipstep3 = False
else:
normalize = None
# step 1: find all explicit files
results, work, dirsnotfound = self._walkexplicit(match, subrepos)
skipstep3 = skipstep3 and not (work or dirsnotfound)
work = [d for d in work if not dirignore(d)]
wadd = work.append
# step 2: visit subdirectories
while work:
nd = work.pop()
skip = None
if nd == '.':
nd = ''
else:
skip = '.hg'
try:
entries = listdir(join(nd), stat=True, skip=skip)
except OSError, inst:
if inst.errno in (errno.EACCES, errno.ENOENT):
match.bad(self.pathto(nd), inst.strerror)
continue
raise
for f, kind, st in entries:
if normalize:
nf = normalize(nd and (nd + "/" + f) or f, True, True)
else:
nf = nd and (nd + "/" + f) or f
if nf not in results:
if kind == dirkind:
if not ignore(nf):
if matchtdir:
matchtdir(nf)
wadd(nf)
if nf in dmap and (matchalways or matchfn(nf)):
results[nf] = None
elif kind == regkind or kind == lnkkind:
if nf in dmap:
if matchalways or matchfn(nf):
results[nf] = st
elif (matchalways or matchfn(nf)) and not ignore(nf):
results[nf] = st
elif nf in dmap and (matchalways or matchfn(nf)):
results[nf] = None
for s in subrepos:
del results[s]
del results['.hg']
# step 3: visit remaining files from dmap
if not skipstep3 and not exact:
# If a dmap file is not in results yet, it was either
# a) not matching matchfn b) ignored, c) missing, or d) under a
# symlink directory.
if not results and matchalways:
visit = dmap.keys()
else:
visit = [f for f in dmap if f not in results and matchfn(f)]
visit.sort()
if unknown:
# unknown == True means we walked all dirs under the roots
# that wasn't ignored, and everything that matched was stat'ed
# and is already in results.
# The rest must thus be ignored or under a symlink.
audit_path = pathutil.pathauditor(self._root)
for nf in iter(visit):
# Report ignored items in the dmap as long as they are not
# under a symlink directory.
if audit_path.check(nf):
try:
results[nf] = lstat(join(nf))
# file was just ignored, no links, and exists
except OSError:
# file doesn't exist
results[nf] = None
else:
# It's either missing or under a symlink directory
# which we in this case report as missing
results[nf] = None
else:
# We may not have walked the full directory tree above,
# so stat and check everything we missed.
nf = iter(visit).next
for st in util.statfiles([join(i) for i in visit]):
results[nf()] = st
return results
def status(self, match, subrepos, ignored, clean, unknown):
'''Determine the status of the working copy relative to the
dirstate and return a tuple of lists (unsure, modified, added,
removed, deleted, unknown, ignored, clean), where:
unsure:
files that might have been modified since the dirstate was
written, but need to be read to be sure (size is the same
but mtime differs)
modified:
files that have definitely been modified since the dirstate
was written (different size or mode)
added:
files that have been explicitly added with hg add
removed:
files that have been explicitly removed with hg remove
deleted:
files that have been deleted through other means ("missing")
unknown:
files not in the dirstate that are not ignored
ignored:
files not in the dirstate that are ignored
(by _dirignore())
clean:
files that have definitely not been modified since the
dirstate was written
'''
listignored, listclean, listunknown = ignored, clean, unknown
lookup, modified, added, unknown, ignored = [], [], [], [], []
removed, deleted, clean = [], [], []
dmap = self._map
ladd = lookup.append # aka "unsure"
madd = modified.append
aadd = added.append
uadd = unknown.append
iadd = ignored.append
radd = removed.append
dadd = deleted.append
cadd = clean.append
mexact = match.exact
dirignore = self._dirignore
checkexec = self._checkexec
copymap = self._copymap
lastnormaltime = self._lastnormaltime
# We need to do full walks when either
# - we're listing all clean files, or
# - match.traversedir does something, because match.traversedir should
# be called for every dir in the working dir
full = listclean or match.traversedir is not None
for fn, st in self.walk(match, subrepos, listunknown, listignored,
full=full).iteritems():
if fn not in dmap:
if (listignored or mexact(fn)) and dirignore(fn):
if listignored:
iadd(fn)
else:
uadd(fn)
continue
# This is equivalent to 'state, mode, size, time = dmap[fn]' but not
# written like that for performance reasons. dmap[fn] is not a
# Python tuple in compiled builds. The CPython UNPACK_SEQUENCE
# opcode has fast paths when the value to be unpacked is a tuple or
# a list, but falls back to creating a full-fledged iterator in
# general. That is much slower than simply accessing and storing the
# tuple members one by one.
t = dmap[fn]
state = t[0]
mode = t[1]
size = t[2]
time = t[3]
if not st and state in "nma":
dadd(fn)
elif state == 'n':
mtime = int(st.st_mtime)
if (size >= 0 and
((size != st.st_size and size != st.st_size & _rangemask)
or ((mode ^ st.st_mode) & 0100 and checkexec))
or size == -2 # other parent
or fn in copymap):
madd(fn)
elif time != mtime and time != mtime & _rangemask:
ladd(fn)
elif mtime == lastnormaltime:
# fn may have been changed in the same timeslot without
# changing its size. This can happen if we quickly do
# multiple commits in a single transaction.
# Force lookup, so we don't miss such a racy file change.
ladd(fn)
elif listclean:
cadd(fn)
elif state == 'm':
madd(fn)
elif state == 'a':
aadd(fn)
elif state == 'r':
radd(fn)
return (lookup, modified, added, removed, deleted, unknown, ignored,
clean)
def matches(self, match):
'''
return files in the dirstate (in whatever state) filtered by match
'''
dmap = self._map
if match.always():
return dmap.keys()
files = match.files()
if match.matchfn == match.exact:
# fast path -- filter the other way around, since typically files is
# much smaller than dmap
return [f for f in files if f in dmap]
if not match.anypats() and util.all(fn in dmap for fn in files):
# fast path -- all the values are known to be files, so just return
# that
return list(files)
return [f for f in dmap if match(f)]