changegroup: store old heads as a set
Previously, the "oldheads" variable was a list. On a repository at
Mozilla with 46,492 heads, profiling revealed that list membership
testing was dominating execution time of applying small changegroups.
This patch converts the list of old heads to a set. This makes
membership testing significantly faster. On the aforementioned
repository with 46,492 heads:
$ hg unbundle <file with 1 changeset>
before: 18.535s wall
after: 1.303s
Consumers of this variable only check for truthiness (`if oldheads`),
length (`len(oldheads)`), and (most importantly) item membership
(`h not in oldheads` - which occurs twice). So, the change to a set
should be safe and suitable for stable.
The practical effect of this change is that changegroup application
and related operations (like `hg push`) no longer exhibit an O(n^2)
CPU explosion as the number of heads grows.
# changegroup.py - Mercurial changegroup manipulation functions
#
# Copyright 2006 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 __future__ import absolute_import
import os
import struct
import tempfile
import weakref
from .i18n import _
from .node import (
hex,
nullrev,
short,
)
from . import (
branchmap,
dagutil,
discovery,
error,
mdiff,
phases,
util,
)
_CHANGEGROUPV1_DELTA_HEADER = "20s20s20s20s"
_CHANGEGROUPV2_DELTA_HEADER = "20s20s20s20s20s"
_CHANGEGROUPV3_DELTA_HEADER = ">20s20s20s20s20sH"
def readexactly(stream, n):
'''read n bytes from stream.read and abort if less was available'''
s = stream.read(n)
if len(s) < n:
raise error.Abort(_("stream ended unexpectedly"
" (got %d bytes, expected %d)")
% (len(s), n))
return s
def getchunk(stream):
"""return the next chunk from stream as a string"""
d = readexactly(stream, 4)
l = struct.unpack(">l", d)[0]
if l <= 4:
if l:
raise error.Abort(_("invalid chunk length %d") % l)
return ""
return readexactly(stream, l - 4)
def chunkheader(length):
"""return a changegroup chunk header (string)"""
return struct.pack(">l", length + 4)
def closechunk():
"""return a changegroup chunk header (string) for a zero-length chunk"""
return struct.pack(">l", 0)
def combineresults(results):
"""logic to combine 0 or more addchangegroup results into one"""
changedheads = 0
result = 1
for ret in results:
# If any changegroup result is 0, return 0
if ret == 0:
result = 0
break
if ret < -1:
changedheads += ret + 1
elif ret > 1:
changedheads += ret - 1
if changedheads > 0:
result = 1 + changedheads
elif changedheads < 0:
result = -1 + changedheads
return result
def writechunks(ui, chunks, filename, vfs=None):
"""Write chunks to a file and return its filename.
The stream is assumed to be a bundle file.
Existing files will not be overwritten.
If no filename is specified, a temporary file is created.
"""
fh = None
cleanup = None
try:
if filename:
if vfs:
fh = vfs.open(filename, "wb")
else:
# Increase default buffer size because default is usually
# small (4k is common on Linux).
fh = open(filename, "wb", 131072)
else:
fd, filename = tempfile.mkstemp(prefix="hg-bundle-", suffix=".hg")
fh = os.fdopen(fd, "wb")
cleanup = filename
for c in chunks:
fh.write(c)
cleanup = None
return filename
finally:
if fh is not None:
fh.close()
if cleanup is not None:
if filename and vfs:
vfs.unlink(cleanup)
else:
os.unlink(cleanup)
class cg1unpacker(object):
"""Unpacker for cg1 changegroup streams.
A changegroup unpacker handles the framing of the revision data in
the wire format. Most consumers will want to use the apply()
method to add the changes from the changegroup to a repository.
If you're forwarding a changegroup unmodified to another consumer,
use getchunks(), which returns an iterator of changegroup
chunks. This is mostly useful for cases where you need to know the
data stream has ended by observing the end of the changegroup.
deltachunk() is useful only if you're applying delta data. Most
consumers should prefer apply() instead.
A few other public methods exist. Those are used only for
bundlerepo and some debug commands - their use is discouraged.
"""
deltaheader = _CHANGEGROUPV1_DELTA_HEADER
deltaheadersize = struct.calcsize(deltaheader)
version = '01'
_grouplistcount = 1 # One list of files after the manifests
def __init__(self, fh, alg, extras=None):
if alg is None:
alg = 'UN'
if alg not in util.compengines.supportedbundletypes:
raise error.Abort(_('unknown stream compression type: %s')
% alg)
if alg == 'BZ':
alg = '_truncatedBZ'
compengine = util.compengines.forbundletype(alg)
self._stream = compengine.decompressorreader(fh)
self._type = alg
self.extras = extras or {}
self.callback = None
# These methods (compressed, read, seek, tell) all appear to only
# be used by bundlerepo, but it's a little hard to tell.
def compressed(self):
return self._type is not None and self._type != 'UN'
def read(self, l):
return self._stream.read(l)
def seek(self, pos):
return self._stream.seek(pos)
def tell(self):
return self._stream.tell()
def close(self):
return self._stream.close()
def _chunklength(self):
d = readexactly(self._stream, 4)
l = struct.unpack(">l", d)[0]
if l <= 4:
if l:
raise error.Abort(_("invalid chunk length %d") % l)
return 0
if self.callback:
self.callback()
return l - 4
def changelogheader(self):
"""v10 does not have a changelog header chunk"""
return {}
def manifestheader(self):
"""v10 does not have a manifest header chunk"""
return {}
def filelogheader(self):
"""return the header of the filelogs chunk, v10 only has the filename"""
l = self._chunklength()
if not l:
return {}
fname = readexactly(self._stream, l)
return {'filename': fname}
def _deltaheader(self, headertuple, prevnode):
node, p1, p2, cs = headertuple
if prevnode is None:
deltabase = p1
else:
deltabase = prevnode
flags = 0
return node, p1, p2, deltabase, cs, flags
def deltachunk(self, prevnode):
l = self._chunklength()
if not l:
return {}
headerdata = readexactly(self._stream, self.deltaheadersize)
header = struct.unpack(self.deltaheader, headerdata)
delta = readexactly(self._stream, l - self.deltaheadersize)
node, p1, p2, deltabase, cs, flags = self._deltaheader(header, prevnode)
return {'node': node, 'p1': p1, 'p2': p2, 'cs': cs,
'deltabase': deltabase, 'delta': delta, 'flags': flags}
def getchunks(self):
"""returns all the chunks contains in the bundle
Used when you need to forward the binary stream to a file or another
network API. To do so, it parse the changegroup data, otherwise it will
block in case of sshrepo because it don't know the end of the stream.
"""
# an empty chunkgroup is the end of the changegroup
# a changegroup has at least 2 chunkgroups (changelog and manifest).
# after that, changegroup versions 1 and 2 have a series of groups
# with one group per file. changegroup 3 has a series of directory
# manifests before the files.
count = 0
emptycount = 0
while emptycount < self._grouplistcount:
empty = True
count += 1
while True:
chunk = getchunk(self)
if not chunk:
if empty and count > 2:
emptycount += 1
break
empty = False
yield chunkheader(len(chunk))
pos = 0
while pos < len(chunk):
next = pos + 2**20
yield chunk[pos:next]
pos = next
yield closechunk()
def _unpackmanifests(self, repo, revmap, trp, prog, numchanges):
# We know that we'll never have more manifests than we had
# changesets.
self.callback = prog(_('manifests'), numchanges)
# no need to check for empty manifest group here:
# if the result of the merge of 1 and 2 is the same in 3 and 4,
# no new manifest will be created and the manifest group will
# be empty during the pull
self.manifestheader()
repo.manifestlog._revlog.addgroup(self, revmap, trp)
repo.ui.progress(_('manifests'), None)
self.callback = None
def apply(self, repo, srctype, url, emptyok=False,
targetphase=phases.draft, expectedtotal=None):
"""Add the changegroup returned by source.read() to this repo.
srctype is a string like 'push', 'pull', or 'unbundle'. url is
the URL of the repo where this changegroup is coming from.
Return an integer summarizing the change to this repo:
- nothing changed or no source: 0
- more heads than before: 1+added heads (2..n)
- fewer heads than before: -1-removed heads (-2..-n)
- number of heads stays the same: 1
"""
repo = repo.unfiltered()
def csmap(x):
repo.ui.debug("add changeset %s\n" % short(x))
return len(cl)
def revmap(x):
return cl.rev(x)
changesets = files = revisions = 0
try:
with repo.transaction("\n".join([srctype,
util.hidepassword(url)])) as tr:
# The transaction could have been created before and already
# carries source information. In this case we use the top
# level data. We overwrite the argument because we need to use
# the top level value (if they exist) in this function.
srctype = tr.hookargs.setdefault('source', srctype)
url = tr.hookargs.setdefault('url', url)
repo.hook('prechangegroup', throw=True, **tr.hookargs)
# write changelog data to temp files so concurrent readers
# will not see an inconsistent view
cl = repo.changelog
cl.delayupdate(tr)
oldheads = set(cl.heads())
trp = weakref.proxy(tr)
# pull off the changeset group
repo.ui.status(_("adding changesets\n"))
clstart = len(cl)
class prog(object):
def __init__(self, step, total):
self._step = step
self._total = total
self._count = 1
def __call__(self):
repo.ui.progress(self._step, self._count,
unit=_('chunks'), total=self._total)
self._count += 1
self.callback = prog(_('changesets'), expectedtotal)
efiles = set()
def onchangelog(cl, node):
efiles.update(cl.readfiles(node))
self.changelogheader()
srccontent = cl.addgroup(self, csmap, trp,
addrevisioncb=onchangelog)
efiles = len(efiles)
if not (srccontent or emptyok):
raise error.Abort(_("received changelog group is empty"))
clend = len(cl)
changesets = clend - clstart
repo.ui.progress(_('changesets'), None)
self.callback = None
# pull off the manifest group
repo.ui.status(_("adding manifests\n"))
self._unpackmanifests(repo, revmap, trp, prog, changesets)
needfiles = {}
if repo.ui.configbool('server', 'validate', default=False):
cl = repo.changelog
ml = repo.manifestlog
# validate incoming csets have their manifests
for cset in xrange(clstart, clend):
mfnode = cl.changelogrevision(cset).manifest
mfest = ml[mfnode].readdelta()
# store file nodes we must see
for f, n in mfest.iteritems():
needfiles.setdefault(f, set()).add(n)
# process the files
repo.ui.status(_("adding file changes\n"))
newrevs, newfiles = _addchangegroupfiles(
repo, self, revmap, trp, efiles, needfiles)
revisions += newrevs
files += newfiles
dh = 0
if oldheads:
heads = cl.heads()
dh = len(heads) - len(oldheads)
for h in heads:
if h not in oldheads and repo[h].closesbranch():
dh -= 1
htext = ""
if dh:
htext = _(" (%+d heads)") % dh
repo.ui.status(_("added %d changesets"
" with %d changes to %d files%s\n")
% (changesets, revisions, files, htext))
repo.invalidatevolatilesets()
if changesets > 0:
if 'node' not in tr.hookargs:
tr.hookargs['node'] = hex(cl.node(clstart))
tr.hookargs['node_last'] = hex(cl.node(clend - 1))
hookargs = dict(tr.hookargs)
else:
hookargs = dict(tr.hookargs)
hookargs['node'] = hex(cl.node(clstart))
hookargs['node_last'] = hex(cl.node(clend - 1))
repo.hook('pretxnchangegroup', throw=True, **hookargs)
added = [cl.node(r) for r in xrange(clstart, clend)]
publishing = repo.publishing()
if srctype in ('push', 'serve'):
# Old servers can not push the boundary themselves.
# New servers won't push the boundary if changeset already
# exists locally as secret
#
# We should not use added here but the list of all change in
# the bundle
if publishing:
phases.advanceboundary(repo, tr, phases.public,
srccontent)
else:
# Those changesets have been pushed from the
# outside, their phases are going to be pushed
# alongside. Therefor `targetphase` is
# ignored.
phases.advanceboundary(repo, tr, phases.draft,
srccontent)
phases.retractboundary(repo, tr, phases.draft, added)
elif srctype != 'strip':
# publishing only alter behavior during push
#
# strip should not touch boundary at all
phases.retractboundary(repo, tr, targetphase, added)
if changesets > 0:
if srctype != 'strip':
# During strip, branchcache is invalid but
# coming call to `destroyed` will repair it.
# In other case we can safely update cache on
# disk.
repo.ui.debug('updating the branch cache\n')
branchmap.updatecache(repo.filtered('served'))
def runhooks():
# These hooks run when the lock releases, not when the
# transaction closes. So it's possible for the changelog
# to have changed since we last saw it.
if clstart >= len(repo):
return
repo.hook("changegroup", **hookargs)
for n in added:
args = hookargs.copy()
args['node'] = hex(n)
del args['node_last']
repo.hook("incoming", **args)
newheads = [h for h in repo.heads()
if h not in oldheads]
repo.ui.log("incoming",
"%s incoming changes - new heads: %s\n",
len(added),
', '.join([hex(c[:6]) for c in newheads]))
tr.addpostclose('changegroup-runhooks-%020i' % clstart,
lambda tr: repo._afterlock(runhooks))
finally:
repo.ui.flush()
# never return 0 here:
if dh < 0:
return dh - 1
else:
return dh + 1
class cg2unpacker(cg1unpacker):
"""Unpacker for cg2 streams.
cg2 streams add support for generaldelta, so the delta header
format is slightly different. All other features about the data
remain the same.
"""
deltaheader = _CHANGEGROUPV2_DELTA_HEADER
deltaheadersize = struct.calcsize(deltaheader)
version = '02'
def _deltaheader(self, headertuple, prevnode):
node, p1, p2, deltabase, cs = headertuple
flags = 0
return node, p1, p2, deltabase, cs, flags
class cg3unpacker(cg2unpacker):
"""Unpacker for cg3 streams.
cg3 streams add support for exchanging treemanifests and revlog
flags. It adds the revlog flags to the delta header and an empty chunk
separating manifests and files.
"""
deltaheader = _CHANGEGROUPV3_DELTA_HEADER
deltaheadersize = struct.calcsize(deltaheader)
version = '03'
_grouplistcount = 2 # One list of manifests and one list of files
def _deltaheader(self, headertuple, prevnode):
node, p1, p2, deltabase, cs, flags = headertuple
return node, p1, p2, deltabase, cs, flags
def _unpackmanifests(self, repo, revmap, trp, prog, numchanges):
super(cg3unpacker, self)._unpackmanifests(repo, revmap, trp, prog,
numchanges)
for chunkdata in iter(self.filelogheader, {}):
# If we get here, there are directory manifests in the changegroup
d = chunkdata["filename"]
repo.ui.debug("adding %s revisions\n" % d)
dirlog = repo.manifestlog._revlog.dirlog(d)
if not dirlog.addgroup(self, revmap, trp):
raise error.Abort(_("received dir revlog group is empty"))
class headerlessfixup(object):
def __init__(self, fh, h):
self._h = h
self._fh = fh
def read(self, n):
if self._h:
d, self._h = self._h[:n], self._h[n:]
if len(d) < n:
d += readexactly(self._fh, n - len(d))
return d
return readexactly(self._fh, n)
class cg1packer(object):
deltaheader = _CHANGEGROUPV1_DELTA_HEADER
version = '01'
def __init__(self, repo, bundlecaps=None):
"""Given a source repo, construct a bundler.
bundlecaps is optional and can be used to specify the set of
capabilities which can be used to build the bundle.
"""
# Set of capabilities we can use to build the bundle.
if bundlecaps is None:
bundlecaps = set()
self._bundlecaps = bundlecaps
# experimental config: bundle.reorder
reorder = repo.ui.config('bundle', 'reorder', 'auto')
if reorder == 'auto':
reorder = None
else:
reorder = util.parsebool(reorder)
self._repo = repo
self._reorder = reorder
self._progress = repo.ui.progress
if self._repo.ui.verbose and not self._repo.ui.debugflag:
self._verbosenote = self._repo.ui.note
else:
self._verbosenote = lambda s: None
def close(self):
return closechunk()
def fileheader(self, fname):
return chunkheader(len(fname)) + fname
# Extracted both for clarity and for overriding in extensions.
def _sortgroup(self, revlog, nodelist, lookup):
"""Sort nodes for change group and turn them into revnums."""
# for generaldelta revlogs, we linearize the revs; this will both be
# much quicker and generate a much smaller bundle
if (revlog._generaldelta and self._reorder is None) or self._reorder:
dag = dagutil.revlogdag(revlog)
return dag.linearize(set(revlog.rev(n) for n in nodelist))
else:
return sorted([revlog.rev(n) for n in nodelist])
def group(self, nodelist, revlog, lookup, units=None):
"""Calculate a delta group, yielding a sequence of changegroup chunks
(strings).
Given a list of changeset revs, return a set of deltas and
metadata corresponding to nodes. The first delta is
first parent(nodelist[0]) -> nodelist[0], the receiver is
guaranteed to have this parent as it has all history before
these changesets. In the case firstparent is nullrev the
changegroup starts with a full revision.
If units is not None, progress detail will be generated, units specifies
the type of revlog that is touched (changelog, manifest, etc.).
"""
# if we don't have any revisions touched by these changesets, bail
if len(nodelist) == 0:
yield self.close()
return
revs = self._sortgroup(revlog, nodelist, lookup)
# add the parent of the first rev
p = revlog.parentrevs(revs[0])[0]
revs.insert(0, p)
# build deltas
total = len(revs) - 1
msgbundling = _('bundling')
for r in xrange(len(revs) - 1):
if units is not None:
self._progress(msgbundling, r + 1, unit=units, total=total)
prev, curr = revs[r], revs[r + 1]
linknode = lookup(revlog.node(curr))
for c in self.revchunk(revlog, curr, prev, linknode):
yield c
if units is not None:
self._progress(msgbundling, None)
yield self.close()
# filter any nodes that claim to be part of the known set
def prune(self, revlog, missing, commonrevs):
rr, rl = revlog.rev, revlog.linkrev
return [n for n in missing if rl(rr(n)) not in commonrevs]
def _packmanifests(self, dir, mfnodes, lookuplinknode):
"""Pack flat manifests into a changegroup stream."""
assert not dir
for chunk in self.group(mfnodes, self._repo.manifestlog._revlog,
lookuplinknode, units=_('manifests')):
yield chunk
def _manifestsdone(self):
return ''
def generate(self, commonrevs, clnodes, fastpathlinkrev, source):
'''yield a sequence of changegroup chunks (strings)'''
repo = self._repo
cl = repo.changelog
clrevorder = {}
mfs = {} # needed manifests
fnodes = {} # needed file nodes
changedfiles = set()
# Callback for the changelog, used to collect changed files and manifest
# nodes.
# Returns the linkrev node (identity in the changelog case).
def lookupcl(x):
c = cl.read(x)
clrevorder[x] = len(clrevorder)
n = c[0]
# record the first changeset introducing this manifest version
mfs.setdefault(n, x)
# Record a complete list of potentially-changed files in
# this manifest.
changedfiles.update(c[3])
return x
self._verbosenote(_('uncompressed size of bundle content:\n'))
size = 0
for chunk in self.group(clnodes, cl, lookupcl, units=_('changesets')):
size += len(chunk)
yield chunk
self._verbosenote(_('%8.i (changelog)\n') % size)
# We need to make sure that the linkrev in the changegroup refers to
# the first changeset that introduced the manifest or file revision.
# The fastpath is usually safer than the slowpath, because the filelogs
# are walked in revlog order.
#
# When taking the slowpath with reorder=None and the manifest revlog
# uses generaldelta, the manifest may be walked in the "wrong" order.
# Without 'clrevorder', we would get an incorrect linkrev (see fix in
# cc0ff93d0c0c).
#
# When taking the fastpath, we are only vulnerable to reordering
# of the changelog itself. The changelog never uses generaldelta, so
# it is only reordered when reorder=True. To handle this case, we
# simply take the slowpath, which already has the 'clrevorder' logic.
# This was also fixed in cc0ff93d0c0c.
fastpathlinkrev = fastpathlinkrev and not self._reorder
# Treemanifests don't work correctly with fastpathlinkrev
# either, because we don't discover which directory nodes to
# send along with files. This could probably be fixed.
fastpathlinkrev = fastpathlinkrev and (
'treemanifest' not in repo.requirements)
for chunk in self.generatemanifests(commonrevs, clrevorder,
fastpathlinkrev, mfs, fnodes):
yield chunk
mfs.clear()
clrevs = set(cl.rev(x) for x in clnodes)
if not fastpathlinkrev:
def linknodes(unused, fname):
return fnodes.get(fname, {})
else:
cln = cl.node
def linknodes(filerevlog, fname):
llr = filerevlog.linkrev
fln = filerevlog.node
revs = ((r, llr(r)) for r in filerevlog)
return dict((fln(r), cln(lr)) for r, lr in revs if lr in clrevs)
for chunk in self.generatefiles(changedfiles, linknodes, commonrevs,
source):
yield chunk
yield self.close()
if clnodes:
repo.hook('outgoing', node=hex(clnodes[0]), source=source)
def generatemanifests(self, commonrevs, clrevorder, fastpathlinkrev, mfs,
fnodes):
repo = self._repo
mfl = repo.manifestlog
dirlog = mfl._revlog.dirlog
tmfnodes = {'': mfs}
# Callback for the manifest, used to collect linkrevs for filelog
# revisions.
# Returns the linkrev node (collected in lookupcl).
def makelookupmflinknode(dir):
if fastpathlinkrev:
assert not dir
return mfs.__getitem__
def lookupmflinknode(x):
"""Callback for looking up the linknode for manifests.
Returns the linkrev node for the specified manifest.
SIDE EFFECT:
1) fclnodes gets populated with the list of relevant
file nodes if we're not using fastpathlinkrev
2) When treemanifests are in use, collects treemanifest nodes
to send
Note that this means manifests must be completely sent to
the client before you can trust the list of files and
treemanifests to send.
"""
clnode = tmfnodes[dir][x]
mdata = mfl.get(dir, x).readfast(shallow=True)
for p, n, fl in mdata.iterentries():
if fl == 't': # subdirectory manifest
subdir = dir + p + '/'
tmfclnodes = tmfnodes.setdefault(subdir, {})
tmfclnode = tmfclnodes.setdefault(n, clnode)
if clrevorder[clnode] < clrevorder[tmfclnode]:
tmfclnodes[n] = clnode
else:
f = dir + p
fclnodes = fnodes.setdefault(f, {})
fclnode = fclnodes.setdefault(n, clnode)
if clrevorder[clnode] < clrevorder[fclnode]:
fclnodes[n] = clnode
return clnode
return lookupmflinknode
size = 0
while tmfnodes:
dir = min(tmfnodes)
nodes = tmfnodes[dir]
prunednodes = self.prune(dirlog(dir), nodes, commonrevs)
if not dir or prunednodes:
for x in self._packmanifests(dir, prunednodes,
makelookupmflinknode(dir)):
size += len(x)
yield x
del tmfnodes[dir]
self._verbosenote(_('%8.i (manifests)\n') % size)
yield self._manifestsdone()
# The 'source' parameter is useful for extensions
def generatefiles(self, changedfiles, linknodes, commonrevs, source):
repo = self._repo
progress = self._progress
msgbundling = _('bundling')
total = len(changedfiles)
# for progress output
msgfiles = _('files')
for i, fname in enumerate(sorted(changedfiles)):
filerevlog = repo.file(fname)
if not filerevlog:
raise error.Abort(_("empty or missing revlog for %s") % fname)
linkrevnodes = linknodes(filerevlog, fname)
# Lookup for filenodes, we collected the linkrev nodes above in the
# fastpath case and with lookupmf in the slowpath case.
def lookupfilelog(x):
return linkrevnodes[x]
filenodes = self.prune(filerevlog, linkrevnodes, commonrevs)
if filenodes:
progress(msgbundling, i + 1, item=fname, unit=msgfiles,
total=total)
h = self.fileheader(fname)
size = len(h)
yield h
for chunk in self.group(filenodes, filerevlog, lookupfilelog):
size += len(chunk)
yield chunk
self._verbosenote(_('%8.i %s\n') % (size, fname))
progress(msgbundling, None)
def deltaparent(self, revlog, rev, p1, p2, prev):
return prev
def revchunk(self, revlog, rev, prev, linknode):
node = revlog.node(rev)
p1, p2 = revlog.parentrevs(rev)
base = self.deltaparent(revlog, rev, p1, p2, prev)
prefix = ''
if revlog.iscensored(base) or revlog.iscensored(rev):
try:
delta = revlog.revision(node, raw=True)
except error.CensoredNodeError as e:
delta = e.tombstone
if base == nullrev:
prefix = mdiff.trivialdiffheader(len(delta))
else:
baselen = revlog.rawsize(base)
prefix = mdiff.replacediffheader(baselen, len(delta))
elif base == nullrev:
delta = revlog.revision(node, raw=True)
prefix = mdiff.trivialdiffheader(len(delta))
else:
delta = revlog.revdiff(base, rev)
p1n, p2n = revlog.parents(node)
basenode = revlog.node(base)
flags = revlog.flags(rev)
meta = self.builddeltaheader(node, p1n, p2n, basenode, linknode, flags)
meta += prefix
l = len(meta) + len(delta)
yield chunkheader(l)
yield meta
yield delta
def builddeltaheader(self, node, p1n, p2n, basenode, linknode, flags):
# do nothing with basenode, it is implicitly the previous one in HG10
# do nothing with flags, it is implicitly 0 for cg1 and cg2
return struct.pack(self.deltaheader, node, p1n, p2n, linknode)
class cg2packer(cg1packer):
version = '02'
deltaheader = _CHANGEGROUPV2_DELTA_HEADER
def __init__(self, repo, bundlecaps=None):
super(cg2packer, self).__init__(repo, bundlecaps)
if self._reorder is None:
# Since generaldelta is directly supported by cg2, reordering
# generally doesn't help, so we disable it by default (treating
# bundle.reorder=auto just like bundle.reorder=False).
self._reorder = False
def deltaparent(self, revlog, rev, p1, p2, prev):
dp = revlog.deltaparent(rev)
if dp == nullrev and revlog.storedeltachains:
# Avoid sending full revisions when delta parent is null. Pick prev
# in that case. It's tempting to pick p1 in this case, as p1 will
# be smaller in the common case. However, computing a delta against
# p1 may require resolving the raw text of p1, which could be
# expensive. The revlog caches should have prev cached, meaning
# less CPU for changegroup generation. There is likely room to add
# a flag and/or config option to control this behavior.
return prev
elif dp == nullrev:
# revlog is configured to use full snapshot for a reason,
# stick to full snapshot.
return nullrev
elif dp not in (p1, p2, prev):
# Pick prev when we can't be sure remote has the base revision.
return prev
else:
return dp
def builddeltaheader(self, node, p1n, p2n, basenode, linknode, flags):
# Do nothing with flags, it is implicitly 0 in cg1 and cg2
return struct.pack(self.deltaheader, node, p1n, p2n, basenode, linknode)
class cg3packer(cg2packer):
version = '03'
deltaheader = _CHANGEGROUPV3_DELTA_HEADER
def _packmanifests(self, dir, mfnodes, lookuplinknode):
if dir:
yield self.fileheader(dir)
dirlog = self._repo.manifestlog._revlog.dirlog(dir)
for chunk in self.group(mfnodes, dirlog, lookuplinknode,
units=_('manifests')):
yield chunk
def _manifestsdone(self):
return self.close()
def builddeltaheader(self, node, p1n, p2n, basenode, linknode, flags):
return struct.pack(
self.deltaheader, node, p1n, p2n, basenode, linknode, flags)
_packermap = {'01': (cg1packer, cg1unpacker),
# cg2 adds support for exchanging generaldelta
'02': (cg2packer, cg2unpacker),
# cg3 adds support for exchanging revlog flags and treemanifests
'03': (cg3packer, cg3unpacker),
}
def allsupportedversions(repo):
versions = set(_packermap.keys())
if not (repo.ui.configbool('experimental', 'changegroup3') or
repo.ui.configbool('experimental', 'treemanifest') or
'treemanifest' in repo.requirements):
versions.discard('03')
return versions
# Changegroup versions that can be applied to the repo
def supportedincomingversions(repo):
return allsupportedversions(repo)
# Changegroup versions that can be created from the repo
def supportedoutgoingversions(repo):
versions = allsupportedversions(repo)
if 'treemanifest' in repo.requirements:
# Versions 01 and 02 support only flat manifests and it's just too
# expensive to convert between the flat manifest and tree manifest on
# the fly. Since tree manifests are hashed differently, all of history
# would have to be converted. Instead, we simply don't even pretend to
# support versions 01 and 02.
versions.discard('01')
versions.discard('02')
return versions
def safeversion(repo):
# Finds the smallest version that it's safe to assume clients of the repo
# will support. For example, all hg versions that support generaldelta also
# support changegroup 02.
versions = supportedoutgoingversions(repo)
if 'generaldelta' in repo.requirements:
versions.discard('01')
assert versions
return min(versions)
def getbundler(version, repo, bundlecaps=None):
assert version in supportedoutgoingversions(repo)
return _packermap[version][0](repo, bundlecaps)
def getunbundler(version, fh, alg, extras=None):
return _packermap[version][1](fh, alg, extras=extras)
def _changegroupinfo(repo, nodes, source):
if repo.ui.verbose or source == 'bundle':
repo.ui.status(_("%d changesets found\n") % len(nodes))
if repo.ui.debugflag:
repo.ui.debug("list of changesets:\n")
for node in nodes:
repo.ui.debug("%s\n" % hex(node))
def getsubsetraw(repo, outgoing, bundler, source, fastpath=False):
repo = repo.unfiltered()
commonrevs = outgoing.common
csets = outgoing.missing
heads = outgoing.missingheads
# We go through the fast path if we get told to, or if all (unfiltered
# heads have been requested (since we then know there all linkrevs will
# be pulled by the client).
heads.sort()
fastpathlinkrev = fastpath or (
repo.filtername is None and heads == sorted(repo.heads()))
repo.hook('preoutgoing', throw=True, source=source)
_changegroupinfo(repo, csets, source)
return bundler.generate(commonrevs, csets, fastpathlinkrev, source)
def getsubset(repo, outgoing, bundler, source, fastpath=False):
gengroup = getsubsetraw(repo, outgoing, bundler, source, fastpath)
return getunbundler(bundler.version, util.chunkbuffer(gengroup), None,
{'clcount': len(outgoing.missing)})
def changegroupsubset(repo, roots, heads, source, version='01'):
"""Compute a changegroup consisting of all the nodes that are
descendants of any of the roots and ancestors of any of the heads.
Return a chunkbuffer object whose read() method will return
successive changegroup chunks.
It is fairly complex as determining which filenodes and which
manifest nodes need to be included for the changeset to be complete
is non-trivial.
Another wrinkle is doing the reverse, figuring out which changeset in
the changegroup a particular filenode or manifestnode belongs to.
"""
outgoing = discovery.outgoing(repo, missingroots=roots, missingheads=heads)
bundler = getbundler(version, repo)
return getsubset(repo, outgoing, bundler, source)
def getlocalchangegroupraw(repo, source, outgoing, bundlecaps=None,
version='01'):
"""Like getbundle, but taking a discovery.outgoing as an argument.
This is only implemented for local repos and reuses potentially
precomputed sets in outgoing. Returns a raw changegroup generator."""
if not outgoing.missing:
return None
bundler = getbundler(version, repo, bundlecaps)
return getsubsetraw(repo, outgoing, bundler, source)
def getlocalchangegroup(repo, source, outgoing, bundlecaps=None,
version='01'):
"""Like getbundle, but taking a discovery.outgoing as an argument.
This is only implemented for local repos and reuses potentially
precomputed sets in outgoing."""
if not outgoing.missing:
return None
bundler = getbundler(version, repo, bundlecaps)
return getsubset(repo, outgoing, bundler, source)
def getchangegroup(repo, source, outgoing, bundlecaps=None,
version='01'):
"""Like changegroupsubset, but returns the set difference between the
ancestors of heads and the ancestors common.
If heads is None, use the local heads. If common is None, use [nullid].
The nodes in common might not all be known locally due to the way the
current discovery protocol works.
"""
return getlocalchangegroup(repo, source, outgoing, bundlecaps=bundlecaps,
version=version)
def changegroup(repo, basenodes, source):
# to avoid a race we use changegroupsubset() (issue1320)
return changegroupsubset(repo, basenodes, repo.heads(), source)
def _addchangegroupfiles(repo, source, revmap, trp, expectedfiles, needfiles):
revisions = 0
files = 0
for chunkdata in iter(source.filelogheader, {}):
files += 1
f = chunkdata["filename"]
repo.ui.debug("adding %s revisions\n" % f)
repo.ui.progress(_('files'), files, unit=_('files'),
total=expectedfiles)
fl = repo.file(f)
o = len(fl)
try:
if not fl.addgroup(source, revmap, trp):
raise error.Abort(_("received file revlog group is empty"))
except error.CensoredBaseError as e:
raise error.Abort(_("received delta base is censored: %s") % e)
revisions += len(fl) - o
if f in needfiles:
needs = needfiles[f]
for new in xrange(o, len(fl)):
n = fl.node(new)
if n in needs:
needs.remove(n)
else:
raise error.Abort(
_("received spurious file revlog entry"))
if not needs:
del needfiles[f]
repo.ui.progress(_('files'), None)
for f, needs in needfiles.iteritems():
fl = repo.file(f)
for n in needs:
try:
fl.rev(n)
except error.LookupError:
raise error.Abort(
_('missing file data for %s:%s - run hg verify') %
(f, hex(n)))
return revisions, files