Mercurial > public > mercurial-scm > hg-stable
diff mercurial/changegroup.py @ 47094:119790e1c67c
cg4: introduce protocol flag to signify the presence of sidedata
We need a way of signaling whether the current revision has sidedata or not,
and re-using the revision flags would waste potential revlog flags and mix two
normally independent layers.
In this change, we add a single byte at the start of the ch4 delta header to
set potential protocol flags. We also reclaim the revlog flag for sidedata,
since it is no longer used, in its place now lives the (also experimental)
copytracing flag.
When generating deltas, apply the `CG_FLAG_SIDEDATA` flag if there is sidedata.
When applying the deltas, if said flag is present, the next chunk contains the
sidedata.
Differential Revision: https://phab.mercurial-scm.org/D10343
| author | Rapha?l Gom?s <rgomes@octobus.net> |
|---|---|
| date | Sat, 10 Apr 2021 11:27:40 +0200 |
| parents | 08e26ef4ad35 |
| children | 3aab2330b7d3 |
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--- a/mercurial/changegroup.py Thu Apr 08 16:34:11 2021 +0200 +++ b/mercurial/changegroup.py Sat Apr 10 11:27:40 2021 +0200 @@ -34,10 +34,12 @@ from .interfaces import repository from .revlogutils import sidedata as sidedatamod from .revlogutils import constants as revlog_constants +from .utils import storageutil _CHANGEGROUPV1_DELTA_HEADER = struct.Struct(b"20s20s20s20s") _CHANGEGROUPV2_DELTA_HEADER = struct.Struct(b"20s20s20s20s20s") _CHANGEGROUPV3_DELTA_HEADER = struct.Struct(b">20s20s20s20s20sH") +_CHANGEGROUPV4_DELTA_HEADER = struct.Struct(b">B20s20s20s20s20sH") LFS_REQUIREMENT = b'lfs' @@ -194,7 +196,8 @@ else: deltabase = prevnode flags = 0 - return node, p1, p2, deltabase, cs, flags + protocol_flags = 0 + return node, p1, p2, deltabase, cs, flags, protocol_flags def deltachunk(self, prevnode): l = self._chunklength() @@ -203,10 +206,9 @@ headerdata = readexactly(self._stream, self.deltaheadersize) header = self.deltaheader.unpack(headerdata) delta = readexactly(self._stream, l - self.deltaheadersize) - node, p1, p2, deltabase, cs, flags = self._deltaheader(header, prevnode) - # cg4 forward-compat - sidedata = {} - return (node, p1, p2, cs, deltabase, delta, flags, sidedata) + header = self._deltaheader(header, prevnode) + node, p1, p2, deltabase, cs, flags, protocol_flags = header + return node, p1, p2, cs, deltabase, delta, flags, protocol_flags def getchunks(self): """returns all the chunks contains in the bundle @@ -597,7 +599,8 @@ def _deltaheader(self, headertuple, prevnode): node, p1, p2, deltabase, cs = headertuple flags = 0 - return node, p1, p2, deltabase, cs, flags + protocol_flags = 0 + return node, p1, p2, deltabase, cs, flags, protocol_flags class cg3unpacker(cg2unpacker): @@ -615,7 +618,8 @@ def _deltaheader(self, headertuple, prevnode): node, p1, p2, deltabase, cs, flags = headertuple - return node, p1, p2, deltabase, cs, flags + protocol_flags = 0 + return node, p1, p2, deltabase, cs, flags, protocol_flags def _unpackmanifests(self, repo, revmap, trp, prog, addrevisioncb=None): super(cg3unpacker, self)._unpackmanifests( @@ -638,18 +642,24 @@ cg4 streams add support for exchanging sidedata. """ + deltaheader = _CHANGEGROUPV4_DELTA_HEADER + deltaheadersize = deltaheader.size version = b'04' + def _deltaheader(self, headertuple, prevnode): + protocol_flags, node, p1, p2, deltabase, cs, flags = headertuple + return node, p1, p2, deltabase, cs, flags, protocol_flags + def deltachunk(self, prevnode): res = super(cg4unpacker, self).deltachunk(prevnode) if not res: return res - (node, p1, p2, cs, deltabase, delta, flags, _sidedata) = res + (node, p1, p2, cs, deltabase, delta, flags, protocol_flags) = res - sidedata_raw = getchunk(self._stream) sidedata = {} - if len(sidedata_raw) > 0: + if protocol_flags & storageutil.CG_FLAG_SIDEDATA: + sidedata_raw = getchunk(self._stream) sidedata = sidedatamod.deserialize_sidedata(sidedata_raw) return node, p1, p2, cs, deltabase, delta, flags, sidedata @@ -695,10 +705,10 @@ yield prefix yield data - sidedata = delta.sidedata - if sidedata is not None: + if delta.protocol_flags & storageutil.CG_FLAG_SIDEDATA: # Need a separate chunk for sidedata to be able to differentiate # "raw delta" length and sidedata length + sidedata = delta.sidedata yield chunkheader(len(sidedata)) yield sidedata @@ -1640,11 +1650,18 @@ fullnodes=None, remote_sidedata=None, ): - # Same header func as cg3. Sidedata is in a separate chunk from the delta to - # differenciate "raw delta" and sidedata. - builddeltaheader = lambda d: _CHANGEGROUPV3_DELTA_HEADER.pack( - d.node, d.p1node, d.p2node, d.basenode, d.linknode, d.flags - ) + # Sidedata is in a separate chunk from the delta to differentiate + # "raw delta" and sidedata. + def builddeltaheader(d): + return _CHANGEGROUPV4_DELTA_HEADER.pack( + d.protocol_flags, + d.node, + d.p1node, + d.p2node, + d.basenode, + d.linknode, + d.flags, + ) return cgpacker( repo, @@ -1930,7 +1947,6 @@ sd_computers = collections.defaultdict(list) # Computers for categories to remove from sidedata sd_removers = collections.defaultdict(list) - to_generate = remote_sd_categories - repo._wanted_sidedata to_remove = repo._wanted_sidedata - remote_sd_categories if pull: