exthelper: drop the addattr() decorator
Yuya pointed out that this goes against the typical advice to not add attributes
to classes[1]. The evolve extension still uses this a handful of times, so
maybe it should be brought back in the future if a general use is found. But it
isn't nice to have a new helper API that can lead to easy problems.
[1] https://www.mercurial-scm.org/pipermail/mercurial-devel/2018-December/126330.html
from __future__ import absolute_import
import hashlib
import struct
from mercurial.node import hex, nullid
from mercurial import (
pycompat,
util,
)
from . import (
basepack,
constants,
shallowutil,
)
# (filename hash, offset, size)
INDEXFORMAT2 = '!20sQQII'
INDEXENTRYLENGTH2 = struct.calcsize(INDEXFORMAT2)
NODELENGTH = 20
NODEINDEXFORMAT = '!20sQ'
NODEINDEXENTRYLENGTH = struct.calcsize(NODEINDEXFORMAT)
# (node, p1, p2, linknode)
PACKFORMAT = "!20s20s20s20sH"
PACKENTRYLENGTH = 82
ENTRYCOUNTSIZE = 4
INDEXSUFFIX = '.histidx'
PACKSUFFIX = '.histpack'
ANC_NODE = 0
ANC_P1NODE = 1
ANC_P2NODE = 2
ANC_LINKNODE = 3
ANC_COPYFROM = 4
class historypackstore(basepack.basepackstore):
INDEXSUFFIX = INDEXSUFFIX
PACKSUFFIX = PACKSUFFIX
def getpack(self, path):
return historypack(path)
def getancestors(self, name, node, known=None):
for pack in self.packs:
try:
return pack.getancestors(name, node, known=known)
except KeyError:
pass
for pack in self.refresh():
try:
return pack.getancestors(name, node, known=known)
except KeyError:
pass
raise KeyError((name, node))
def getnodeinfo(self, name, node):
for pack in self.packs:
try:
return pack.getnodeinfo(name, node)
except KeyError:
pass
for pack in self.refresh():
try:
return pack.getnodeinfo(name, node)
except KeyError:
pass
raise KeyError((name, node))
def add(self, filename, node, p1, p2, linknode, copyfrom):
raise RuntimeError("cannot add to historypackstore (%s:%s)"
% (filename, hex(node)))
class historypack(basepack.basepack):
INDEXSUFFIX = INDEXSUFFIX
PACKSUFFIX = PACKSUFFIX
SUPPORTED_VERSIONS = [2]
def __init__(self, path):
super(historypack, self).__init__(path)
self.INDEXFORMAT = INDEXFORMAT2
self.INDEXENTRYLENGTH = INDEXENTRYLENGTH2
def getmissing(self, keys):
missing = []
for name, node in keys:
try:
self._findnode(name, node)
except KeyError:
missing.append((name, node))
return missing
def getancestors(self, name, node, known=None):
"""Returns as many ancestors as we're aware of.
return value: {
node: (p1, p2, linknode, copyfrom),
...
}
"""
if known and node in known:
return []
ancestors = self._getancestors(name, node, known=known)
results = {}
for ancnode, p1, p2, linknode, copyfrom in ancestors:
results[ancnode] = (p1, p2, linknode, copyfrom)
if not results:
raise KeyError((name, node))
return results
def getnodeinfo(self, name, node):
# Drop the node from the tuple before returning, since the result should
# just be (p1, p2, linknode, copyfrom)
return self._findnode(name, node)[1:]
def _getancestors(self, name, node, known=None):
if known is None:
known = set()
section = self._findsection(name)
filename, offset, size, nodeindexoffset, nodeindexsize = section
pending = set((node,))
o = 0
while o < size:
if not pending:
break
entry, copyfrom = self._readentry(offset + o)
o += PACKENTRYLENGTH
if copyfrom:
o += len(copyfrom)
ancnode = entry[ANC_NODE]
if ancnode in pending:
pending.remove(ancnode)
p1node = entry[ANC_P1NODE]
p2node = entry[ANC_P2NODE]
if p1node != nullid and p1node not in known:
pending.add(p1node)
if p2node != nullid and p2node not in known:
pending.add(p2node)
yield (ancnode, p1node, p2node, entry[ANC_LINKNODE], copyfrom)
def _readentry(self, offset):
data = self._data
entry = struct.unpack(PACKFORMAT, data[offset:offset + PACKENTRYLENGTH])
copyfrom = None
copyfromlen = entry[ANC_COPYFROM]
if copyfromlen != 0:
offset += PACKENTRYLENGTH
copyfrom = data[offset:offset + copyfromlen]
return entry, copyfrom
def add(self, filename, node, p1, p2, linknode, copyfrom):
raise RuntimeError("cannot add to historypack (%s:%s)" %
(filename, hex(node)))
def _findnode(self, name, node):
if self.VERSION == 0:
ancestors = self._getancestors(name, node)
for ancnode, p1node, p2node, linknode, copyfrom in ancestors:
if ancnode == node:
return (ancnode, p1node, p2node, linknode, copyfrom)
else:
section = self._findsection(name)
nodeindexoffset, nodeindexsize = section[3:]
entry = self._bisect(node, nodeindexoffset,
nodeindexoffset + nodeindexsize,
NODEINDEXENTRYLENGTH)
if entry is not None:
node, offset = struct.unpack(NODEINDEXFORMAT, entry)
entry, copyfrom = self._readentry(offset)
# Drop the copyfromlen from the end of entry, and replace it
# with the copyfrom string.
return entry[:4] + (copyfrom,)
raise KeyError("unable to find history for %s:%s" % (name, hex(node)))
def _findsection(self, name):
params = self.params
namehash = hashlib.sha1(name).digest()
fanoutkey = struct.unpack(params.fanoutstruct,
namehash[:params.fanoutprefix])[0]
fanout = self._fanouttable
start = fanout[fanoutkey] + params.indexstart
indexend = self._indexend
for i in pycompat.xrange(fanoutkey + 1, params.fanoutcount):
end = fanout[i] + params.indexstart
if end != start:
break
else:
end = indexend
entry = self._bisect(namehash, start, end, self.INDEXENTRYLENGTH)
if not entry:
raise KeyError(name)
rawentry = struct.unpack(self.INDEXFORMAT, entry)
x, offset, size, nodeindexoffset, nodeindexsize = rawentry
rawnamelen = self._index[nodeindexoffset:nodeindexoffset +
constants.FILENAMESIZE]
actualnamelen = struct.unpack('!H', rawnamelen)[0]
nodeindexoffset += constants.FILENAMESIZE
actualname = self._index[nodeindexoffset:nodeindexoffset +
actualnamelen]
if actualname != name:
raise KeyError("found file name %s when looking for %s" %
(actualname, name))
nodeindexoffset += actualnamelen
filenamelength = struct.unpack('!H', self._data[offset:offset +
constants.FILENAMESIZE])[0]
offset += constants.FILENAMESIZE
actualname = self._data[offset:offset + filenamelength]
offset += filenamelength
if name != actualname:
raise KeyError("found file name %s when looking for %s" %
(actualname, name))
# Skip entry list size
offset += ENTRYCOUNTSIZE
nodelistoffset = offset
nodelistsize = (size - constants.FILENAMESIZE - filenamelength -
ENTRYCOUNTSIZE)
return (name, nodelistoffset, nodelistsize,
nodeindexoffset, nodeindexsize)
def _bisect(self, node, start, end, entrylen):
# Bisect between start and end to find node
origstart = start
startnode = self._index[start:start + NODELENGTH]
endnode = self._index[end:end + NODELENGTH]
if startnode == node:
return self._index[start:start + entrylen]
elif endnode == node:
return self._index[end:end + entrylen]
else:
while start < end - entrylen:
mid = start + (end - start) // 2
mid = mid - ((mid - origstart) % entrylen)
midnode = self._index[mid:mid + NODELENGTH]
if midnode == node:
return self._index[mid:mid + entrylen]
if node > midnode:
start = mid
startnode = midnode
elif node < midnode:
end = mid
endnode = midnode
return None
def markledger(self, ledger, options=None):
for filename, node in self:
ledger.markhistoryentry(self, filename, node)
def cleanup(self, ledger):
entries = ledger.sources.get(self, [])
allkeys = set(self)
repackedkeys = set((e.filename, e.node) for e in entries if
e.historyrepacked)
if len(allkeys - repackedkeys) == 0:
if self.path not in ledger.created:
util.unlinkpath(self.indexpath, ignoremissing=True)
util.unlinkpath(self.packpath, ignoremissing=True)
def __iter__(self):
for f, n, x, x, x, x in self.iterentries():
yield f, n
def iterentries(self):
# Start at 1 to skip the header
offset = 1
while offset < self.datasize:
data = self._data
# <2 byte len> + <filename>
filenamelen = struct.unpack('!H', data[offset:offset +
constants.FILENAMESIZE])[0]
offset += constants.FILENAMESIZE
filename = data[offset:offset + filenamelen]
offset += filenamelen
revcount = struct.unpack('!I', data[offset:offset +
ENTRYCOUNTSIZE])[0]
offset += ENTRYCOUNTSIZE
for i in pycompat.xrange(revcount):
entry = struct.unpack(PACKFORMAT, data[offset:offset +
PACKENTRYLENGTH])
offset += PACKENTRYLENGTH
copyfrom = data[offset:offset + entry[ANC_COPYFROM]]
offset += entry[ANC_COPYFROM]
yield (filename, entry[ANC_NODE], entry[ANC_P1NODE],
entry[ANC_P2NODE], entry[ANC_LINKNODE], copyfrom)
self._pagedin += PACKENTRYLENGTH
# If we've read a lot of data from the mmap, free some memory.
self.freememory()
class mutablehistorypack(basepack.mutablebasepack):
"""A class for constructing and serializing a histpack file and index.
A history pack is a pair of files that contain the revision history for
various file revisions in Mercurial. It contains only revision history (like
parent pointers and linknodes), not any revision content information.
It consists of two files, with the following format:
.histpack
The pack itself is a series of file revisions with some basic header
information on each.
datapack = <version: 1 byte>
[<filesection>,...]
filesection = <filename len: 2 byte unsigned int>
<filename>
<revision count: 4 byte unsigned int>
[<revision>,...]
revision = <node: 20 byte>
<p1node: 20 byte>
<p2node: 20 byte>
<linknode: 20 byte>
<copyfromlen: 2 byte>
<copyfrom>
The revisions within each filesection are stored in topological order
(newest first). If a given entry has a parent from another file (a copy)
then p1node is the node from the other file, and copyfrom is the
filepath of the other file.
.histidx
The index file provides a mapping from filename to the file section in
the histpack. In V1 it also contains sub-indexes for specific nodes
within each file. It consists of three parts, the fanout, the file index
and the node indexes.
The file index is a list of index entries, sorted by filename hash (one
per file section in the pack). Each entry has:
- node (The 20 byte hash of the filename)
- pack entry offset (The location of this file section in the histpack)
- pack content size (The on-disk length of this file section's pack
data)
- node index offset (The location of the file's node index in the index
file) [1]
- node index size (the on-disk length of this file's node index) [1]
The fanout is a quick lookup table to reduce the number of steps for
bisecting the index. It is a series of 4 byte pointers to positions
within the index. It has 2^16 entries, which corresponds to hash
prefixes [00, 01, 02,..., FD, FE, FF]. Example: the pointer in slot 4F
points to the index position of the first revision whose node starts
with 4F. This saves log(2^16) bisect steps.
dataidx = <fanouttable>
<file count: 8 byte unsigned> [1]
<fileindex>
<node count: 8 byte unsigned> [1]
[<nodeindex>,...] [1]
fanouttable = [<index offset: 4 byte unsigned int>,...] (2^16 entries)
fileindex = [<file index entry>,...]
fileindexentry = <node: 20 byte>
<pack file section offset: 8 byte unsigned int>
<pack file section size: 8 byte unsigned int>
<node index offset: 4 byte unsigned int> [1]
<node index size: 4 byte unsigned int> [1]
nodeindex = <filename>[<node index entry>,...] [1]
filename = <filename len : 2 byte unsigned int><filename value> [1]
nodeindexentry = <node: 20 byte> [1]
<pack file node offset: 8 byte unsigned int> [1]
[1]: new in version 1.
"""
INDEXSUFFIX = INDEXSUFFIX
PACKSUFFIX = PACKSUFFIX
SUPPORTED_VERSIONS = [2]
def __init__(self, ui, packpath, version=2):
super(mutablehistorypack, self).__init__(ui, packpath, version=version)
self.files = {}
self.entrylocations = {}
self.fileentries = {}
self.INDEXFORMAT = INDEXFORMAT2
self.INDEXENTRYLENGTH = INDEXENTRYLENGTH2
self.NODEINDEXFORMAT = NODEINDEXFORMAT
self.NODEINDEXENTRYLENGTH = NODEINDEXENTRYLENGTH
def add(self, filename, node, p1, p2, linknode, copyfrom):
copyfrom = copyfrom or ''
copyfromlen = struct.pack('!H', len(copyfrom))
self.fileentries.setdefault(filename, []).append((node, p1, p2,
linknode,
copyfromlen,
copyfrom))
def _write(self):
for filename in sorted(self.fileentries):
entries = self.fileentries[filename]
sectionstart = self.packfp.tell()
# Write the file section content
entrymap = dict((e[0], e) for e in entries)
def parentfunc(node):
x, p1, p2, x, x, x = entrymap[node]
parents = []
if p1 != nullid:
parents.append(p1)
if p2 != nullid:
parents.append(p2)
return parents
sortednodes = list(reversed(shallowutil.sortnodes(
(e[0] for e in entries),
parentfunc)))
# Write the file section header
self.writeraw("%s%s%s" % (
struct.pack('!H', len(filename)),
filename,
struct.pack('!I', len(sortednodes)),
))
sectionlen = constants.FILENAMESIZE + len(filename) + 4
rawstrings = []
# Record the node locations for the index
locations = self.entrylocations.setdefault(filename, {})
offset = sectionstart + sectionlen
for node in sortednodes:
locations[node] = offset
raw = '%s%s%s%s%s%s' % entrymap[node]
rawstrings.append(raw)
offset += len(raw)
rawdata = ''.join(rawstrings)
sectionlen += len(rawdata)
self.writeraw(rawdata)
# Record metadata for the index
self.files[filename] = (sectionstart, sectionlen)
node = hashlib.sha1(filename).digest()
self.entries[node] = node
def close(self, ledger=None):
if self._closed:
return
self._write()
return super(mutablehistorypack, self).close(ledger=ledger)
def createindex(self, nodelocations, indexoffset):
fileindexformat = self.INDEXFORMAT
fileindexlength = self.INDEXENTRYLENGTH
nodeindexformat = self.NODEINDEXFORMAT
nodeindexlength = self.NODEINDEXENTRYLENGTH
files = ((hashlib.sha1(filename).digest(), filename, offset, size)
for filename, (offset, size) in self.files.iteritems())
files = sorted(files)
# node index is after file index size, file index, and node index size
indexlensize = struct.calcsize('!Q')
nodeindexoffset = (indexoffset + indexlensize +
(len(files) * fileindexlength) + indexlensize)
fileindexentries = []
nodeindexentries = []
nodecount = 0
for namehash, filename, offset, size in files:
# File section index
nodelocations = self.entrylocations[filename]
nodeindexsize = len(nodelocations) * nodeindexlength
rawentry = struct.pack(fileindexformat, namehash, offset, size,
nodeindexoffset, nodeindexsize)
# Node index
nodeindexentries.append(struct.pack(constants.FILENAMESTRUCT,
len(filename)) + filename)
nodeindexoffset += constants.FILENAMESIZE + len(filename)
for node, location in sorted(nodelocations.iteritems()):
nodeindexentries.append(struct.pack(nodeindexformat, node,
location))
nodecount += 1
nodeindexoffset += len(nodelocations) * nodeindexlength
fileindexentries.append(rawentry)
nodecountraw = ''
nodecountraw = struct.pack('!Q', nodecount)
return (''.join(fileindexentries) + nodecountraw +
''.join(nodeindexentries))