Mercurial > hg
view mercurial/copies.py @ 12296:d7fff529d85d
clone: only use stream when we understand the revlog format
This patch fixes issues with stream cloning in the presense of parentdelta,
lwcopy and similar additions that change the interpretation of the revlog
format, or the format itself.
Currently, the stream capability is sent like this:
stream=<version of changelog>
But the client doesn't actually check the version number; also, it only checks
the changelog and it doesn't capture the interpretation-changes and
flag-changes in parentdelta and lwcopy.
This patch removes the 'stream' capability whenever we use a non-basic revlog
format, to prevent old clients from receiving incorrect data. In those cases,
a new capability called 'streamreqs' is added instead. Instead of a revlog
version, it comes with a list of revlog-format relevant requirements, which
are a subset of the repository requirements, excluding things that are not
relevant for stream.
New clients use this to determine whether or not they can stream. Old clients
only look for the 'stream' capability, as always. New servers will still send
this when serving old repositories.
author | Sune Foldager <cryo@cyanite.org> |
---|---|
date | Wed, 15 Sep 2010 11:06:22 +0200 |
parents | 4f11978ae45d |
children | ada47c38f4e5 |
line wrap: on
line source
# copies.py - copy detection for Mercurial # # Copyright 2008 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. import util import heapq def _nonoverlap(d1, d2, d3): "Return list of elements in d1 not in d2 or d3" return sorted([d for d in d1 if d not in d3 and d not in d2]) def _dirname(f): s = f.rfind("/") if s == -1: return "" return f[:s] def _dirs(files): d = set() for f in files: f = _dirname(f) while f not in d: d.add(f) f = _dirname(f) return d def _findlimit(repo, a, b): """Find the earliest revision that's an ancestor of a or b but not both, None if no such revision exists. """ # basic idea: # - mark a and b with different sides # - if a parent's children are all on the same side, the parent is # on that side, otherwise it is on no side # - walk the graph in topological order with the help of a heap; # - add unseen parents to side map # - clear side of any parent that has children on different sides # - track number of interesting revs that might still be on a side # - track the lowest interesting rev seen # - quit when interesting revs is zero cl = repo.changelog working = len(cl) # pseudo rev for the working directory if a is None: a = working if b is None: b = working side = {a: -1, b: 1} visit = [-a, -b] heapq.heapify(visit) interesting = len(visit) hascommonancestor = False limit = working while interesting: r = -heapq.heappop(visit) if r == working: parents = [cl.rev(p) for p in repo.dirstate.parents()] else: parents = cl.parentrevs(r) for p in parents: if p < 0: continue if p not in side: # first time we see p; add it to visit side[p] = side[r] if side[p]: interesting += 1 heapq.heappush(visit, -p) elif side[p] and side[p] != side[r]: # p was interesting but now we know better side[p] = 0 interesting -= 1 hascommonancestor = True if side[r]: limit = r # lowest rev visited interesting -= 1 if not hascommonancestor: return None return limit def copies(repo, c1, c2, ca, checkdirs=False): """ Find moves and copies between context c1 and c2 """ # avoid silly behavior for update from empty dir if not c1 or not c2 or c1 == c2: return {}, {} # avoid silly behavior for parent -> working dir if c2.node() is None and c1.node() == repo.dirstate.parents()[0]: return repo.dirstate.copies(), {} limit = _findlimit(repo, c1.rev(), c2.rev()) if limit is None: # no common ancestor, no copies return {}, {} m1 = c1.manifest() m2 = c2.manifest() ma = ca.manifest() def makectx(f, n): if len(n) != 20: # in a working context? if c1.rev() is None: return c1.filectx(f) return c2.filectx(f) return repo.filectx(f, fileid=n) ctx = util.lrucachefunc(makectx) copy = {} fullcopy = {} diverge = {} def related(f1, f2, limit): # Walk back to common ancestor to see if the two files originate # from the same file. Since workingfilectx's rev() is None it messes # up the integer comparison logic, hence the pre-step check for # None (f1 and f2 can only be workingfilectx's initially). if f1 == f2: return f1 # a match g1, g2 = f1.ancestors(), f2.ancestors() try: f1r, f2r = f1.rev(), f2.rev() if f1r is None: f1 = g1.next() if f2r is None: f2 = g2.next() while 1: f1r, f2r = f1.rev(), f2.rev() if f1r > f2r: f1 = g1.next() elif f2r > f1r: f2 = g2.next() elif f1 == f2: return f1 # a match elif f1r == f2r or f1r < limit or f2r < limit: return False # copy no longer relevant except StopIteration: return False def checkcopies(f, m1, m2): '''check possible copies of f from m1 to m2''' of = None seen = set([f]) for oc in ctx(f, m1[f]).ancestors(): ocr = oc.rev() of = oc.path() if of in seen: # check limit late - grab last rename before if ocr < limit: break continue seen.add(of) fullcopy[f] = of # remember for dir rename detection if of not in m2: continue # no match, keep looking if m2[of] == ma.get(of): break # no merge needed, quit early c2 = ctx(of, m2[of]) cr = related(oc, c2, ca.rev()) if cr and (of == f or of == c2.path()): # non-divergent copy[f] = of of = None break if of in ma: diverge.setdefault(of, []).append(f) repo.ui.debug(" searching for copies back to rev %d\n" % limit) u1 = _nonoverlap(m1, m2, ma) u2 = _nonoverlap(m2, m1, ma) if u1: repo.ui.debug(" unmatched files in local:\n %s\n" % "\n ".join(u1)) if u2: repo.ui.debug(" unmatched files in other:\n %s\n" % "\n ".join(u2)) for f in u1: checkcopies(f, m1, m2) for f in u2: checkcopies(f, m2, m1) diverge2 = set() for of, fl in diverge.items(): if len(fl) == 1: del diverge[of] # not actually divergent else: diverge2.update(fl) # reverse map for below if fullcopy: repo.ui.debug(" all copies found (* = to merge, ! = divergent):\n") for f in fullcopy: note = "" if f in copy: note += "*" if f in diverge2: note += "!" repo.ui.debug(" %s -> %s %s\n" % (f, fullcopy[f], note)) del diverge2 if not fullcopy or not checkdirs: return copy, diverge repo.ui.debug(" checking for directory renames\n") # generate a directory move map d1, d2 = _dirs(m1), _dirs(m2) invalid = set() dirmove = {} # examine each file copy for a potential directory move, which is # when all the files in a directory are moved to a new directory for dst, src in fullcopy.iteritems(): dsrc, ddst = _dirname(src), _dirname(dst) if dsrc in invalid: # already seen to be uninteresting continue elif dsrc in d1 and ddst in d1: # directory wasn't entirely moved locally invalid.add(dsrc) elif dsrc in d2 and ddst in d2: # directory wasn't entirely moved remotely invalid.add(dsrc) elif dsrc in dirmove and dirmove[dsrc] != ddst: # files from the same directory moved to two different places invalid.add(dsrc) else: # looks good so far dirmove[dsrc + "/"] = ddst + "/" for i in invalid: if i in dirmove: del dirmove[i] del d1, d2, invalid if not dirmove: return copy, diverge for d in dirmove: repo.ui.debug(" dir %s -> %s\n" % (d, dirmove[d])) # check unaccounted nonoverlapping files against directory moves for f in u1 + u2: if f not in fullcopy: for d in dirmove: if f.startswith(d): # new file added in a directory that was moved, move it df = dirmove[d] + f[len(d):] if df not in copy: copy[f] = df repo.ui.debug(" file %s -> %s\n" % (f, copy[f])) break return copy, diverge