find-delta: pass the cache-delta usage policy alongside the cache-delta
The idea is to give higher level code more control to what will happens with
the cache delta passed. This should help with controling how we treat delta's
from different sources.
The final goal of this change is to allow for server modes where the client can
blindly accept any server delta without regards to any local constraints. This
will be implemented in later changesets.
# mercurial.revlogutils -- basic utilities for revlog
#
# Copyright 2019 Pierre-Yves David <pierre-yves.david@octobus.net>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
from ..thirdparty import attr
from ..interfaces import repository
# See mercurial.revlogutils.constants for doc
COMP_MODE_INLINE = 2
RANK_UNKNOWN = -1
def offset_type(offset, type):
if (type & ~repository.REVISION_FLAGS_KNOWN) != 0:
raise ValueError(b'unknown revlog index flags: %d' % type)
return int(int(offset) << 16 | type)
def entry(
data_offset,
data_compressed_length,
data_delta_base,
link_rev,
parent_rev_1,
parent_rev_2,
node_id,
flags=0,
data_uncompressed_length=-1,
data_compression_mode=COMP_MODE_INLINE,
sidedata_offset=0,
sidedata_compressed_length=0,
sidedata_compression_mode=COMP_MODE_INLINE,
rank=RANK_UNKNOWN,
):
"""Build one entry from symbolic name
This is useful to abstract the actual detail of how we build the entry
tuple for caller who don't care about it.
This should always be called using keyword arguments. Some arguments have
default value, this match the value used by index version that does not store such data.
"""
return (
offset_type(data_offset, flags),
data_compressed_length,
data_uncompressed_length,
data_delta_base,
link_rev,
parent_rev_1,
parent_rev_2,
node_id,
sidedata_offset,
sidedata_compressed_length,
data_compression_mode,
sidedata_compression_mode,
rank,
)
@attr.s(slots=True, frozen=True)
class revisioninfo:
"""Information about a revision that allows building its fulltext
node: expected hash of the revision
p1, p2: parent revs of the revision
btext: built text cache consisting of a one-element list
cachedelta: (baserev, uncompressed_delta, usage_mode) or None
flags: flags associated to the revision storage
One of btext[0] or cachedelta must be set.
"""
node = attr.ib()
p1 = attr.ib()
p2 = attr.ib()
btext = attr.ib()
textlen = attr.ib()
cachedelta = attr.ib()
flags = attr.ib()