simplestore: use a custom store for the simple store repo
Before, we used the default store, which was based on fncache
and dotencode. After attempting to port tests to work with the
simple store, I realized that fncache was more trouble than it is
worth.
This commit implements a proper store type for the simple repo -
one that isn't based off fncache.
This causes a number of new test failures because of tests
expecting the full fncache store filename encoding. I may
extend the store format in a subsequent commit to take the
filename encoding parts of fncache that we can take
(basically everything except hash encoding, since that isn't
reversible). But for now, let's use encoded store.
As part of this, we implement proper requirements support for
repos created with the simple store. This should have been
done from the beginning, as a requirement is needed to lock
out clients that don't understand a storage format.
A new hghave feature advertising the presence of fncache in repos
has been added. Most tests touching the fncache are now conditional
on that feature.
Other tests have added the optional repo requirement to output.
Differential Revision: https://phab.mercurial-scm.org/D3095
# simplestorerepo.py - Extension that swaps in alternate repository storage.
#
# Copyright 2018 Gregory Szorc <gregory.szorc@gmail.com>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
# To use this with the test suite:
#
# $ HGREPOFEATURES="simplestore" ./run-tests.py \
# --extra-config-opt extensions.simplestore=`pwd`/simplestorerepo.py
from __future__ import absolute_import
import stat
from mercurial.i18n import _
from mercurial.node import (
bin,
hex,
nullid,
nullrev,
)
from mercurial.thirdparty import (
cbor,
)
from mercurial import (
ancestor,
bundlerepo,
error,
extensions,
filelog,
localrepo,
mdiff,
pycompat,
revlog,
store,
)
# Note for extension authors: ONLY specify testedwith = 'ships-with-hg-core' for
# extensions which SHIP WITH MERCURIAL. Non-mainline extensions should
# be specifying the version(s) of Mercurial they are tested with, or
# leave the attribute unspecified.
testedwith = 'ships-with-hg-core'
REQUIREMENT = 'testonly-simplestore'
def validatenode(node):
if isinstance(node, int):
raise ValueError('expected node; got int')
if len(node) != 20:
raise ValueError('expected 20 byte node')
def validaterev(rev):
if not isinstance(rev, int):
raise ValueError('expected int')
class filestorage(object):
"""Implements storage for a tracked path.
Data is stored in the VFS in a directory corresponding to the tracked
path.
Index data is stored in an ``index`` file using CBOR.
Fulltext data is stored in files having names of the node.
"""
def __init__(self, svfs, path):
self._svfs = svfs
self._path = path
self._storepath = b'/'.join([b'data', path])
self._indexpath = b'/'.join([self._storepath, b'index'])
indexdata = self._svfs.tryread(self._indexpath)
if indexdata:
indexdata = cbor.loads(indexdata)
self._indexdata = indexdata or []
self._indexbynode = {}
self._indexbyrev = {}
self.index = []
self._refreshindex()
# This is used by changegroup code :/
self._generaldelta = True
self.storedeltachains = False
self.version = 1
def _refreshindex(self):
self._indexbynode.clear()
self._indexbyrev.clear()
self.index = []
for i, entry in enumerate(self._indexdata):
self._indexbynode[entry[b'node']] = entry
self._indexbyrev[i] = entry
self._indexbynode[nullid] = {
b'node': nullid,
b'p1': nullid,
b'p2': nullid,
b'linkrev': nullrev,
b'flags': 0,
}
self._indexbyrev[nullrev] = {
b'node': nullid,
b'p1': nullid,
b'p2': nullid,
b'linkrev': nullrev,
b'flags': 0,
}
for i, entry in enumerate(self._indexdata):
p1rev, p2rev = self.parentrevs(self.rev(entry[b'node']))
# start, length, rawsize, chainbase, linkrev, p1, p2, node
self.index.append((0, 0, 0, -1, entry[b'linkrev'], p1rev, p2rev,
entry[b'node']))
self.index.append((0, 0, 0, -1, -1, -1, -1, nullid))
def __len__(self):
return len(self._indexdata)
def __iter__(self):
return iter(range(len(self)))
def revs(self, start=0, stop=None):
step = 1
if stop is not None:
if start > stop:
step = -1
stop += step
else:
stop = len(self)
return range(start, stop, step)
def parents(self, node):
validatenode(node)
if node not in self._indexbynode:
raise KeyError('unknown node')
entry = self._indexbynode[node]
return entry[b'p1'], entry[b'p2']
def parentrevs(self, rev):
p1, p2 = self.parents(self._indexbyrev[rev][b'node'])
return self.rev(p1), self.rev(p2)
def rev(self, node):
validatenode(node)
try:
self._indexbynode[node]
except KeyError:
raise error.LookupError(node, self._indexpath, _('no node'))
for rev, entry in self._indexbyrev.items():
if entry[b'node'] == node:
return rev
raise error.ProgrammingError('this should not occur')
def node(self, rev):
validaterev(rev)
return self._indexbyrev[rev][b'node']
def lookup(self, node):
if isinstance(node, int):
return self.node(node)
if len(node) == 20:
self.rev(node)
return node
try:
rev = int(node)
if '%d' % rev != node:
raise ValueError
if rev < 0:
rev = len(self) + rev
if rev < 0 or rev >= len(self):
raise ValueError
return self.node(rev)
except (ValueError, OverflowError):
pass
if len(node) == 40:
try:
rawnode = bin(node)
self.rev(rawnode)
return rawnode
except TypeError:
pass
raise error.LookupError(node, self._path, _('invalid lookup input'))
def linkrev(self, rev):
validaterev(rev)
return self._indexbyrev[rev][b'linkrev']
def flags(self, rev):
validaterev(rev)
return self._indexbyrev[rev][b'flags']
def deltaparent(self, rev):
validaterev(rev)
p1node = self.parents(self.node(rev))[0]
return self.rev(p1node)
def candelta(self, baserev, rev):
validaterev(baserev)
validaterev(rev)
if ((self.flags(baserev) & revlog.REVIDX_RAWTEXT_CHANGING_FLAGS)
or (self.flags(rev) & revlog.REVIDX_RAWTEXT_CHANGING_FLAGS)):
return False
return True
def rawsize(self, rev):
validaterev(rev)
node = self.node(rev)
return len(self.revision(node, raw=True))
def _processflags(self, text, flags, operation, raw=False):
if flags == 0:
return text, True
validatehash = True
# Depending on the operation (read or write), the order might be
# reversed due to non-commutative transforms.
orderedflags = revlog.REVIDX_FLAGS_ORDER
if operation == 'write':
orderedflags = reversed(orderedflags)
for flag in orderedflags:
# If a flagprocessor has been registered for a known flag, apply the
# related operation transform and update result tuple.
if flag & flags:
vhash = True
if flag not in revlog._flagprocessors:
message = _("missing processor for flag '%#x'") % (flag)
raise revlog.RevlogError(message)
processor = revlog._flagprocessors[flag]
if processor is not None:
readtransform, writetransform, rawtransform = processor
if raw:
vhash = rawtransform(self, text)
elif operation == 'read':
text, vhash = readtransform(self, text)
else: # write operation
text, vhash = writetransform(self, text)
validatehash = validatehash and vhash
return text, validatehash
def checkhash(self, text, node, p1=None, p2=None, rev=None):
if p1 is None and p2 is None:
p1, p2 = self.parents(node)
if node != revlog.hash(text, p1, p2):
raise error.RevlogError(_("integrity check failed on %s") %
self._path)
def revision(self, node, raw=False):
validatenode(node)
if node == nullid:
return b''
rev = self.rev(node)
flags = self.flags(rev)
path = b'/'.join([self._storepath, hex(node)])
rawtext = self._svfs.read(path)
text, validatehash = self._processflags(rawtext, flags, 'read', raw=raw)
if validatehash:
self.checkhash(text, node, rev=rev)
return text
def read(self, node):
validatenode(node)
revision = self.revision(node)
if not revision.startswith(b'\1\n'):
return revision
start = revision.index(b'\1\n', 2)
return revision[start + 2:]
def renamed(self, node):
validatenode(node)
if self.parents(node)[0] != nullid:
return False
fulltext = self.revision(node)
m = filelog.parsemeta(fulltext)[0]
if m and 'copy' in m:
return m['copy'], bin(m['copyrev'])
return False
def cmp(self, node, text):
validatenode(node)
t = text
if text.startswith(b'\1\n'):
t = b'\1\n\1\n' + text
p1, p2 = self.parents(node)
if revlog.hash(t, p1, p2) == node:
return False
if self.iscensored(self.rev(node)):
return text != b''
if self.renamed(node):
t2 = self.read(node)
return t2 != text
return True
def size(self, rev):
validaterev(rev)
node = self._indexbyrev[rev][b'node']
if self.renamed(node):
return len(self.read(node))
if self.iscensored(rev):
return 0
return len(self.revision(node))
def iscensored(self, rev):
validaterev(rev)
return self.flags(rev) & revlog.REVIDX_ISCENSORED
def commonancestorsheads(self, a, b):
validatenode(a)
validatenode(b)
a = self.rev(a)
b = self.rev(b)
ancestors = ancestor.commonancestorsheads(self.parentrevs, a, b)
return pycompat.maplist(self.node, ancestors)
def descendants(self, revs):
# This is a copy of revlog.descendants()
first = min(revs)
if first == nullrev:
for i in self:
yield i
return
seen = set(revs)
for i in self.revs(start=first + 1):
for x in self.parentrevs(i):
if x != nullrev and x in seen:
seen.add(i)
yield i
break
# Required by verify.
def files(self):
entries = self._svfs.listdir(self._storepath)
# Strip out undo.backup.* files created as part of transaction
# recording.
entries = [f for f in entries if not f.startswith('undo.backup.')]
return [b'/'.join((self._storepath, f)) for f in entries]
# Required by verify.
def checksize(self):
return 0, 0
def add(self, text, meta, transaction, linkrev, p1, p2):
if meta or text.startswith(b'\1\n'):
text = filelog.packmeta(meta, text)
return self.addrevision(text, transaction, linkrev, p1, p2)
def addrevision(self, text, transaction, linkrev, p1, p2, node=None,
flags=0):
validatenode(p1)
validatenode(p2)
if flags:
node = node or revlog.hash(text, p1, p2)
rawtext, validatehash = self._processflags(text, flags, 'write')
node = node or revlog.hash(text, p1, p2)
if node in self._indexbynode:
return node
if validatehash:
self.checkhash(rawtext, node, p1=p1, p2=p2)
path = b'/'.join([self._storepath, hex(node)])
self._svfs.write(path, text)
self._indexdata.append({
b'node': node,
b'p1': p1,
b'p2': p2,
b'linkrev': linkrev,
b'flags': flags,
})
self._reflectindexupdate()
return node
def _reflectindexupdate(self):
self._refreshindex()
self._svfs.write(self._indexpath, cbor.dumps(self._indexdata))
def addgroup(self, deltas, linkmapper, transaction, addrevisioncb=None):
nodes = []
transaction.addbackup(self._indexpath)
for node, p1, p2, linknode, deltabase, delta, flags in deltas:
linkrev = linkmapper(linknode)
nodes.append(node)
if node in self._indexbynode:
continue
# Need to resolve the fulltext from the delta base.
if deltabase == nullid:
text = mdiff.patch(b'', delta)
else:
text = mdiff.patch(self.revision(deltabase), delta)
self.addrevision(text, transaction, linkrev, p1, p2, flags)
if addrevisioncb:
addrevisioncb(self, node)
return nodes
def revdiff(self, rev1, rev2):
validaterev(rev1)
validaterev(rev2)
node1 = self.node(rev1)
node2 = self.node(rev2)
return mdiff.textdiff(self.revision(node1, raw=True),
self.revision(node2, raw=True))
def headrevs(self):
# Assume all revisions are heads by default.
revishead = {rev: True for rev in self._indexbyrev}
for rev, entry in self._indexbyrev.items():
# Unset head flag for all seen parents.
revishead[self.rev(entry[b'p1'])] = False
revishead[self.rev(entry[b'p2'])] = False
return [rev for rev, ishead in sorted(revishead.items())
if ishead]
def heads(self, start=None, stop=None):
# This is copied from revlog.py.
if start is None and stop is None:
if not len(self):
return [nullid]
return [self.node(r) for r in self.headrevs()]
if start is None:
start = nullid
if stop is None:
stop = []
stoprevs = set([self.rev(n) for n in stop])
startrev = self.rev(start)
reachable = {startrev}
heads = {startrev}
parentrevs = self.parentrevs
for r in self.revs(start=startrev + 1):
for p in parentrevs(r):
if p in reachable:
if r not in stoprevs:
reachable.add(r)
heads.add(r)
if p in heads and p not in stoprevs:
heads.remove(p)
return [self.node(r) for r in heads]
def children(self, node):
validatenode(node)
# This is a copy of revlog.children().
c = []
p = self.rev(node)
for r in self.revs(start=p + 1):
prevs = [pr for pr in self.parentrevs(r) if pr != nullrev]
if prevs:
for pr in prevs:
if pr == p:
c.append(self.node(r))
elif p == nullrev:
c.append(self.node(r))
return c
def getstrippoint(self, minlink):
# This is largely a copy of revlog.getstrippoint().
brokenrevs = set()
strippoint = len(self)
heads = {}
futurelargelinkrevs = set()
for head in self.headrevs():
headlinkrev = self.linkrev(head)
heads[head] = headlinkrev
if headlinkrev >= minlink:
futurelargelinkrevs.add(headlinkrev)
# This algorithm involves walking down the rev graph, starting at the
# heads. Since the revs are topologically sorted according to linkrev,
# once all head linkrevs are below the minlink, we know there are
# no more revs that could have a linkrev greater than minlink.
# So we can stop walking.
while futurelargelinkrevs:
strippoint -= 1
linkrev = heads.pop(strippoint)
if linkrev < minlink:
brokenrevs.add(strippoint)
else:
futurelargelinkrevs.remove(linkrev)
for p in self.parentrevs(strippoint):
if p != nullrev:
plinkrev = self.linkrev(p)
heads[p] = plinkrev
if plinkrev >= minlink:
futurelargelinkrevs.add(plinkrev)
return strippoint, brokenrevs
def strip(self, minlink, transaction):
if not len(self):
return
rev, _ignored = self.getstrippoint(minlink)
if rev == len(self):
return
# Purge index data starting at the requested revision.
self._indexdata[rev:] = []
self._reflectindexupdate()
def issimplestorefile(f, kind, st):
if kind != stat.S_IFREG:
return False
if store.isrevlog(f, kind, st):
return False
# Ignore transaction undo files.
if f.startswith('undo.'):
return False
# Otherwise assume it belongs to the simple store.
return True
class simplestore(store.encodedstore):
def datafiles(self):
for x in super(simplestore, self).datafiles():
yield x
# Supplement with non-revlog files.
extrafiles = self._walk('data', True, filefilter=issimplestorefile)
for unencoded, encoded, size in extrafiles:
try:
unencoded = store.decodefilename(unencoded)
except KeyError:
unencoded = None
yield unencoded, encoded, size
def reposetup(ui, repo):
if not repo.local():
return
if isinstance(repo, bundlerepo.bundlerepository):
raise error.Abort(_('cannot use simple store with bundlerepo'))
class simplestorerepo(repo.__class__):
def file(self, f):
return filestorage(self.svfs, f)
repo.__class__ = simplestorerepo
def featuresetup(ui, supported):
supported.add(REQUIREMENT)
def newreporequirements(orig, repo):
"""Modifies default requirements for new repos to use the simple store."""
requirements = orig(repo)
# These requirements are only used to affect creation of the store
# object. We have our own store. So we can remove them.
# TODO do this once we feel like taking the test hit.
#if 'fncache' in requirements:
# requirements.remove('fncache')
#if 'dotencode' in requirements:
# requirements.remove('dotencode')
requirements.add(REQUIREMENT)
return requirements
def makestore(orig, requirements, path, vfstype):
if REQUIREMENT not in requirements:
return orig(requirements, path, vfstype)
return simplestore(path, vfstype)
def extsetup(ui):
localrepo.featuresetupfuncs.add(featuresetup)
extensions.wrapfunction(localrepo, 'newreporequirements',
newreporequirements)
extensions.wrapfunction(store, 'store', makestore)