manifestmerge: local unknown, remote created: don't traverse symlinks
To figure out what to do with locally unknown files, Mercurial attempts to read
them if they exist. When an attempt is made to read a file that exists but
traverses a symlink, Mercurial aborts.
With this patch, we first ensure that the file doesn't traverse a symlink
before opening it. This is fine because a file being "remote created" means the
symlink doesn't exist remotely, which means it will be deleted in the apply
phase.
# merge.py - directory-level update/merge handling for Mercurial
#
# Copyright 2006, 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, nullrev, hex, bin
from i18n import _
from mercurial import obsolete
import error, util, filemerge, copies, subrepo, worker, dicthelpers
import errno, os, shutil
class mergestate(object):
'''track 3-way merge state of individual files'''
def __init__(self, repo):
self._repo = repo
self._dirty = False
self._read()
def reset(self, node=None):
self._state = {}
if node:
self._local = node
shutil.rmtree(self._repo.join("merge"), True)
self._dirty = False
def _read(self):
self._state = {}
try:
f = self._repo.opener("merge/state")
for i, l in enumerate(f):
if i == 0:
self._local = bin(l[:-1])
else:
bits = l[:-1].split("\0")
self._state[bits[0]] = bits[1:]
f.close()
except IOError, err:
if err.errno != errno.ENOENT:
raise
self._dirty = False
def commit(self):
if self._dirty:
f = self._repo.opener("merge/state", "w")
f.write(hex(self._local) + "\n")
for d, v in self._state.iteritems():
f.write("\0".join([d] + v) + "\n")
f.close()
self._dirty = False
def add(self, fcl, fco, fca, fd):
hash = util.sha1(fcl.path()).hexdigest()
self._repo.opener.write("merge/" + hash, fcl.data())
self._state[fd] = ['u', hash, fcl.path(), fca.path(),
hex(fca.filenode()), fco.path(), fcl.flags()]
self._dirty = True
def __contains__(self, dfile):
return dfile in self._state
def __getitem__(self, dfile):
return self._state[dfile][0]
def __iter__(self):
l = self._state.keys()
l.sort()
for f in l:
yield f
def mark(self, dfile, state):
self._state[dfile][0] = state
self._dirty = True
def resolve(self, dfile, wctx, octx):
if self[dfile] == 'r':
return 0
state, hash, lfile, afile, anode, ofile, flags = self._state[dfile]
fcd = wctx[dfile]
fco = octx[ofile]
fca = self._repo.filectx(afile, fileid=anode)
# "premerge" x flags
flo = fco.flags()
fla = fca.flags()
if 'x' in flags + flo + fla and 'l' not in flags + flo + fla:
if fca.node() == nullid:
self._repo.ui.warn(_('warning: cannot merge flags for %s\n') %
afile)
elif flags == fla:
flags = flo
# restore local
f = self._repo.opener("merge/" + hash)
self._repo.wwrite(dfile, f.read(), flags)
f.close()
r = filemerge.filemerge(self._repo, self._local, lfile, fcd, fco, fca)
if r is None:
# no real conflict
del self._state[dfile]
elif not r:
self.mark(dfile, 'r')
return r
def _checkunknownfile(repo, wctx, mctx, f):
return (not repo.dirstate._ignore(f)
and os.path.isfile(repo.wjoin(f))
and repo.wopener.audit.check(f)
and repo.dirstate.normalize(f) not in repo.dirstate
and mctx[f].cmp(wctx[f]))
def _checkunknown(repo, wctx, mctx):
"check for collisions between unknown files and files in mctx"
error = False
for f in mctx:
if f not in wctx and _checkunknownfile(repo, wctx, mctx, f):
error = True
wctx._repo.ui.warn(_("%s: untracked file differs\n") % f)
if error:
raise util.Abort(_("untracked files in working directory differ "
"from files in requested revision"))
def _forgetremoved(wctx, mctx, branchmerge):
"""
Forget removed files
If we're jumping between revisions (as opposed to merging), and if
neither the working directory nor the target rev has the file,
then we need to remove it from the dirstate, to prevent the
dirstate from listing the file when it is no longer in the
manifest.
If we're merging, and the other revision has removed a file
that is not present in the working directory, we need to mark it
as removed.
"""
actions = []
state = branchmerge and 'r' or 'f'
for f in wctx.deleted():
if f not in mctx:
actions.append((f, state, None, "forget deleted"))
if not branchmerge:
for f in wctx.removed():
if f not in mctx:
actions.append((f, "f", None, "forget removed"))
return actions
def _checkcollision(repo, wmf, actions, prompts):
# build provisional merged manifest up
pmmf = set(wmf)
def addop(f, args):
pmmf.add(f)
def removeop(f, args):
pmmf.discard(f)
def nop(f, args):
pass
def renameop(f, args):
f2, fd, flags = args
if f:
pmmf.discard(f)
pmmf.add(fd)
def mergeop(f, args):
f2, fd, move = args
if move:
pmmf.discard(f)
pmmf.add(fd)
opmap = {
"a": addop,
"d": renameop,
"dr": nop,
"e": nop,
"f": addop, # untracked file should be kept in working directory
"g": addop,
"m": mergeop,
"r": removeop,
"rd": nop,
}
for f, m, args, msg in actions:
op = opmap.get(m)
assert op, m
op(f, args)
opmap = {
"cd": addop,
"dc": addop,
}
for f, m in prompts:
op = opmap.get(m)
assert op, m
op(f, None)
# check case-folding collision in provisional merged manifest
foldmap = {}
for f in sorted(pmmf):
fold = util.normcase(f)
if fold in foldmap:
raise util.Abort(_("case-folding collision between %s and %s")
% (f, foldmap[fold]))
foldmap[fold] = f
def manifestmerge(repo, wctx, p2, pa, branchmerge, force, partial,
acceptremote=False):
"""
Merge p1 and p2 with ancestor pa and generate merge action list
branchmerge and force are as passed in to update
partial = function to filter file lists
acceptremote = accept the incoming changes without prompting
"""
overwrite = force and not branchmerge
actions, copy, movewithdir = [], {}, {}
followcopies = False
if overwrite:
pa = wctx
elif pa == p2: # backwards
pa = wctx.p1()
elif not branchmerge and not wctx.dirty(missing=True):
pass
elif pa and repo.ui.configbool("merge", "followcopies", True):
followcopies = True
# manifests fetched in order are going to be faster, so prime the caches
[x.manifest() for x in
sorted(wctx.parents() + [p2, pa], key=lambda x: x.rev())]
if followcopies:
ret = copies.mergecopies(repo, wctx, p2, pa)
copy, movewithdir, diverge, renamedelete = ret
for of, fl in diverge.iteritems():
actions.append((of, "dr", (fl,), "divergent renames"))
for of, fl in renamedelete.iteritems():
actions.append((of, "rd", (fl,), "rename and delete"))
repo.ui.note(_("resolving manifests\n"))
repo.ui.debug(" branchmerge: %s, force: %s, partial: %s\n"
% (bool(branchmerge), bool(force), bool(partial)))
repo.ui.debug(" ancestor: %s, local: %s, remote: %s\n" % (pa, wctx, p2))
m1, m2, ma = wctx.manifest(), p2.manifest(), pa.manifest()
copied = set(copy.values())
copied.update(movewithdir.values())
if '.hgsubstate' in m1:
# check whether sub state is modified
for s in sorted(wctx.substate):
if wctx.sub(s).dirty():
m1['.hgsubstate'] += "+"
break
aborts, prompts = [], []
# Compare manifests
fdiff = dicthelpers.diff(m1, m2)
flagsdiff = m1.flagsdiff(m2)
diff12 = dicthelpers.join(fdiff, flagsdiff)
for f, (n12, fl12) in diff12.iteritems():
if n12:
n1, n2 = n12
else: # file contents didn't change, but flags did
n1 = n2 = m1.get(f, None)
if n1 is None:
# Since n1 == n2, the file isn't present in m2 either. This
# means that the file was removed or deleted locally and
# removed remotely, but that residual entries remain in flags.
# This can happen in manifests generated by workingctx.
continue
if fl12:
fl1, fl2 = fl12
else: # flags didn't change, file contents did
fl1 = fl2 = m1.flags(f)
if partial and not partial(f):
continue
if n1 and n2:
fla = ma.flags(f)
nol = 'l' not in fl1 + fl2 + fla
a = ma.get(f, nullid)
if n2 == a and fl2 == fla:
pass # remote unchanged - keep local
elif n1 == a and fl1 == fla: # local unchanged - use remote
if n1 == n2: # optimization: keep local content
actions.append((f, "e", (fl2,), "update permissions"))
else:
actions.append((f, "g", (fl2,), "remote is newer"))
elif nol and n2 == a: # remote only changed 'x'
actions.append((f, "e", (fl2,), "update permissions"))
elif nol and n1 == a: # local only changed 'x'
actions.append((f, "g", (fl1,), "remote is newer"))
else: # both changed something
actions.append((f, "m", (f, f, False), "versions differ"))
elif f in copied: # files we'll deal with on m2 side
pass
elif n1 and f in movewithdir: # directory rename
f2 = movewithdir[f]
actions.append((f, "d", (None, f2, fl1),
"remote renamed directory to " + f2))
elif n1 and f in copy:
f2 = copy[f]
actions.append((f, "m", (f2, f, False),
"local copied/moved to " + f2))
elif n1 and f in ma: # clean, a different, no remote
if n1 != ma[f]:
prompts.append((f, "cd")) # prompt changed/deleted
elif n1[20:] == "a": # added, no remote
actions.append((f, "f", None, "remote deleted"))
else:
actions.append((f, "r", None, "other deleted"))
elif n2 and f in movewithdir:
f2 = movewithdir[f]
actions.append((None, "d", (f, f2, fl2),
"local renamed directory to " + f2))
elif n2 and f in copy:
f2 = copy[f]
if f2 in m2:
actions.append((f2, "m", (f, f, False),
"remote copied to " + f))
else:
actions.append((f2, "m", (f, f, True),
"remote moved to " + f))
elif n2 and f not in ma:
# local unknown, remote created: the logic is described by the
# following table:
#
# force branchmerge different | action
# n * n | get
# n * y | abort
# y n * | get
# y y n | get
# y y y | merge
#
# Checking whether the files are different is expensive, so we
# don't do that when we can avoid it.
if force and not branchmerge:
actions.append((f, "g", (fl2,), "remote created"))
else:
different = _checkunknownfile(repo, wctx, p2, f)
if force and branchmerge and different:
actions.append((f, "m", (f, f, False),
"remote differs from untracked local"))
elif not force and different:
aborts.append((f, "ud"))
else:
actions.append((f, "g", (fl2,), "remote created"))
elif n2 and n2 != ma[f]:
prompts.append((f, "dc")) # prompt deleted/changed
for f, m in sorted(aborts):
if m == "ud":
repo.ui.warn(_("%s: untracked file differs\n") % f)
else: assert False, m
if aborts:
raise util.Abort(_("untracked files in working directory differ "
"from files in requested revision"))
if not util.checkcase(repo.path):
# check collision between files only in p2 for clean update
if (not branchmerge and
(force or not wctx.dirty(missing=True, branch=False))):
_checkcollision(repo, m2, [], [])
else:
_checkcollision(repo, m1, actions, prompts)
for f, m in sorted(prompts):
if m == "cd":
if acceptremote:
actions.append((f, "r", None, "remote delete"))
elif repo.ui.promptchoice(
_("local changed %s which remote deleted\n"
"use (c)hanged version or (d)elete?") % f,
(_("&Changed"), _("&Delete")), 0):
actions.append((f, "r", None, "prompt delete"))
else:
actions.append((f, "a", None, "prompt keep"))
elif m == "dc":
if acceptremote:
actions.append((f, "g", (m2.flags(f),), "remote recreating"))
elif repo.ui.promptchoice(
_("remote changed %s which local deleted\n"
"use (c)hanged version or leave (d)eleted?") % f,
(_("&Changed"), _("&Deleted")), 0) == 0:
actions.append((f, "g", (m2.flags(f),), "prompt recreating"))
else: assert False, m
return actions
def actionkey(a):
return a[1] == "r" and -1 or 0, a
def getremove(repo, mctx, overwrite, args):
"""apply usually-non-interactive updates to the working directory
mctx is the context to be merged into the working copy
yields tuples for progress updates
"""
verbose = repo.ui.verbose
unlink = util.unlinkpath
wjoin = repo.wjoin
fctx = mctx.filectx
wwrite = repo.wwrite
audit = repo.wopener.audit
i = 0
for arg in args:
f = arg[0]
if arg[1] == 'r':
if verbose:
repo.ui.note(_("removing %s\n") % f)
audit(f)
try:
unlink(wjoin(f), ignoremissing=True)
except OSError, inst:
repo.ui.warn(_("update failed to remove %s: %s!\n") %
(f, inst.strerror))
else:
if verbose:
repo.ui.note(_("getting %s\n") % f)
wwrite(f, fctx(f).data(), arg[2][0])
if i == 100:
yield i, f
i = 0
i += 1
if i > 0:
yield i, f
def applyupdates(repo, actions, wctx, mctx, actx, overwrite):
"""apply the merge action list to the working directory
wctx is the working copy context
mctx is the context to be merged into the working copy
actx is the context of the common ancestor
Return a tuple of counts (updated, merged, removed, unresolved) that
describes how many files were affected by the update.
"""
updated, merged, removed, unresolved = 0, 0, 0, 0
ms = mergestate(repo)
ms.reset(wctx.p1().node())
moves = []
actions.sort(key=actionkey)
# prescan for merges
for a in actions:
f, m, args, msg = a
repo.ui.debug(" %s: %s -> %s\n" % (f, msg, m))
if m == "m": # merge
f2, fd, move = args
if fd == '.hgsubstate': # merged internally
continue
repo.ui.debug(" preserving %s for resolve of %s\n" % (f, fd))
fcl = wctx[f]
fco = mctx[f2]
if mctx == actx: # backwards, use working dir parent as ancestor
if fcl.parents():
fca = fcl.p1()
else:
fca = repo.filectx(f, fileid=nullrev)
else:
fca = fcl.ancestor(fco, actx)
if not fca:
fca = repo.filectx(f, fileid=nullrev)
ms.add(fcl, fco, fca, fd)
if f != fd and move:
moves.append(f)
audit = repo.wopener.audit
# remove renamed files after safely stored
for f in moves:
if os.path.lexists(repo.wjoin(f)):
repo.ui.debug("removing %s\n" % f)
audit(f)
util.unlinkpath(repo.wjoin(f))
numupdates = len(actions)
workeractions = [a for a in actions if a[1] in 'gr']
updateactions = [a for a in workeractions if a[1] == 'g']
updated = len(updateactions)
removeactions = [a for a in workeractions if a[1] == 'r']
removed = len(removeactions)
actions = [a for a in actions if a[1] not in 'gr']
hgsub = [a[1] for a in workeractions if a[0] == '.hgsubstate']
if hgsub and hgsub[0] == 'r':
subrepo.submerge(repo, wctx, mctx, wctx, overwrite)
z = 0
prog = worker.worker(repo.ui, 0.001, getremove, (repo, mctx, overwrite),
removeactions)
for i, item in prog:
z += i
repo.ui.progress(_('updating'), z, item=item, total=numupdates,
unit=_('files'))
prog = worker.worker(repo.ui, 0.001, getremove, (repo, mctx, overwrite),
updateactions)
for i, item in prog:
z += i
repo.ui.progress(_('updating'), z, item=item, total=numupdates,
unit=_('files'))
if hgsub and hgsub[0] == 'g':
subrepo.submerge(repo, wctx, mctx, wctx, overwrite)
_updating = _('updating')
_files = _('files')
progress = repo.ui.progress
for i, a in enumerate(actions):
f, m, args, msg = a
progress(_updating, z + i + 1, item=f, total=numupdates, unit=_files)
if m == "m": # merge
f2, fd, move = args
if fd == '.hgsubstate': # subrepo states need updating
subrepo.submerge(repo, wctx, mctx, wctx.ancestor(mctx),
overwrite)
continue
audit(fd)
r = ms.resolve(fd, wctx, mctx)
if r is not None and r > 0:
unresolved += 1
else:
if r is None:
updated += 1
else:
merged += 1
elif m == "d": # directory rename
f2, fd, flags = args
if f:
repo.ui.note(_("moving %s to %s\n") % (f, fd))
audit(f)
repo.wwrite(fd, wctx.filectx(f).data(), flags)
util.unlinkpath(repo.wjoin(f))
if f2:
repo.ui.note(_("getting %s to %s\n") % (f2, fd))
repo.wwrite(fd, mctx.filectx(f2).data(), flags)
updated += 1
elif m == "dr": # divergent renames
fl, = args
repo.ui.warn(_("note: possible conflict - %s was renamed "
"multiple times to:\n") % f)
for nf in fl:
repo.ui.warn(" %s\n" % nf)
elif m == "rd": # rename and delete
fl, = args
repo.ui.warn(_("note: possible conflict - %s was deleted "
"and renamed to:\n") % f)
for nf in fl:
repo.ui.warn(" %s\n" % nf)
elif m == "e": # exec
flags, = args
audit(f)
util.setflags(repo.wjoin(f), 'l' in flags, 'x' in flags)
updated += 1
ms.commit()
progress(_updating, None, total=numupdates, unit=_files)
return updated, merged, removed, unresolved
def calculateupdates(repo, tctx, mctx, ancestor, branchmerge, force, partial,
acceptremote=False):
"Calculate the actions needed to merge mctx into tctx"
actions = []
actions += manifestmerge(repo, tctx, mctx,
ancestor,
branchmerge, force,
partial, acceptremote)
if tctx.rev() is None:
actions += _forgetremoved(tctx, mctx, branchmerge)
return actions
def recordupdates(repo, actions, branchmerge):
"record merge actions to the dirstate"
for a in actions:
f, m, args, msg = a
if m == "r": # remove
if branchmerge:
repo.dirstate.remove(f)
else:
repo.dirstate.drop(f)
elif m == "a": # re-add
if not branchmerge:
repo.dirstate.add(f)
elif m == "f": # forget
repo.dirstate.drop(f)
elif m == "e": # exec change
repo.dirstate.normallookup(f)
elif m == "g": # get
if branchmerge:
repo.dirstate.otherparent(f)
else:
repo.dirstate.normal(f)
elif m == "m": # merge
f2, fd, move = args
if branchmerge:
# We've done a branch merge, mark this file as merged
# so that we properly record the merger later
repo.dirstate.merge(fd)
if f != f2: # copy/rename
if move:
repo.dirstate.remove(f)
if f != fd:
repo.dirstate.copy(f, fd)
else:
repo.dirstate.copy(f2, fd)
else:
# We've update-merged a locally modified file, so
# we set the dirstate to emulate a normal checkout
# of that file some time in the past. Thus our
# merge will appear as a normal local file
# modification.
if f2 == fd: # file not locally copied/moved
repo.dirstate.normallookup(fd)
if move:
repo.dirstate.drop(f)
elif m == "d": # directory rename
f2, fd, flag = args
if not f2 and f not in repo.dirstate:
# untracked file moved
continue
if branchmerge:
repo.dirstate.add(fd)
if f:
repo.dirstate.remove(f)
repo.dirstate.copy(f, fd)
if f2:
repo.dirstate.copy(f2, fd)
else:
repo.dirstate.normal(fd)
if f:
repo.dirstate.drop(f)
def update(repo, node, branchmerge, force, partial, ancestor=None,
mergeancestor=False):
"""
Perform a merge between the working directory and the given node
node = the node to update to, or None if unspecified
branchmerge = whether to merge between branches
force = whether to force branch merging or file overwriting
partial = a function to filter file lists (dirstate not updated)
mergeancestor = whether it is merging with an ancestor. If true,
we should accept the incoming changes for any prompts that occur.
If false, merging with an ancestor (fast-forward) is only allowed
between different named branches. This flag is used by rebase extension
as a temporary fix and should be avoided in general.
The table below shows all the behaviors of the update command
given the -c and -C or no options, whether the working directory
is dirty, whether a revision is specified, and the relationship of
the parent rev to the target rev (linear, on the same named
branch, or on another named branch).
This logic is tested by test-update-branches.t.
-c -C dirty rev | linear same cross
n n n n | ok (1) x
n n n y | ok ok ok
n n y * | merge (2) (2)
n y * * | --- discard ---
y n y * | --- (3) ---
y n n * | --- ok ---
y y * * | --- (4) ---
x = can't happen
* = don't-care
1 = abort: crosses branches (use 'hg merge' or 'hg update -c')
2 = abort: crosses branches (use 'hg merge' to merge or
use 'hg update -C' to discard changes)
3 = abort: uncommitted local changes
4 = incompatible options (checked in commands.py)
Return the same tuple as applyupdates().
"""
onode = node
wlock = repo.wlock()
try:
wc = repo[None]
if node is None:
# tip of current branch
try:
node = repo.branchtip(wc.branch())
except error.RepoLookupError:
if wc.branch() == "default": # no default branch!
node = repo.lookup("tip") # update to tip
else:
raise util.Abort(_("branch %s not found") % wc.branch())
overwrite = force and not branchmerge
pl = wc.parents()
p1, p2 = pl[0], repo[node]
if ancestor:
pa = repo[ancestor]
else:
pa = p1.ancestor(p2)
fp1, fp2, xp1, xp2 = p1.node(), p2.node(), str(p1), str(p2)
### check phase
if not overwrite and len(pl) > 1:
raise util.Abort(_("outstanding uncommitted merges"))
if branchmerge:
if pa == p2:
raise util.Abort(_("merging with a working directory ancestor"
" has no effect"))
elif pa == p1:
if not mergeancestor and p1.branch() == p2.branch():
raise util.Abort(_("nothing to merge"),
hint=_("use 'hg update' "
"or check 'hg heads'"))
if not force and (wc.files() or wc.deleted()):
raise util.Abort(_("outstanding uncommitted changes"),
hint=_("use 'hg status' to list changes"))
for s in sorted(wc.substate):
if wc.sub(s).dirty():
raise util.Abort(_("outstanding uncommitted changes in "
"subrepository '%s'") % s)
elif not overwrite:
if pa not in (p1, p2): # nolinear
dirty = wc.dirty(missing=True)
if dirty or onode is None:
# Branching is a bit strange to ensure we do the minimal
# amount of call to obsolete.background.
foreground = obsolete.foreground(repo, [p1.node()])
# note: the <node> variable contains a random identifier
if repo[node].node() in foreground:
pa = p1 # allow updating to successors
elif dirty:
msg = _("crosses branches (merge branches or use"
" --clean to discard changes)")
raise util.Abort(msg)
else: # node is none
msg = _("crosses branches (merge branches or update"
" --check to force update)")
raise util.Abort(msg)
else:
# Allow jumping branches if clean and specific rev given
pa = p1
### calculate phase
actions = calculateupdates(repo, wc, p2, pa,
branchmerge, force, partial, mergeancestor)
### apply phase
if not branchmerge: # just jump to the new rev
fp1, fp2, xp1, xp2 = fp2, nullid, xp2, ''
if not partial:
repo.hook('preupdate', throw=True, parent1=xp1, parent2=xp2)
stats = applyupdates(repo, actions, wc, p2, pa, overwrite)
if not partial:
repo.setparents(fp1, fp2)
recordupdates(repo, actions, branchmerge)
if not branchmerge:
repo.dirstate.setbranch(p2.branch())
finally:
wlock.release()
if not partial:
repo.hook('update', parent1=xp1, parent2=xp2, error=stats[3])
return stats