mirror of
https://github.com/facebook/sapling.git
synced 2024-10-09 00:14:35 +03:00
71f171494e
The current way we use the 'delayupdate' mechanism is wrong. We call 'delayupdate' right after the transaction retrieval, then we call 'finalize' right before calling 'tr.close()'. The 'finalize' call will -always- result in a flush to disk, making the data available to all readers. But the 'tr.close()' may be a no-op if the transaction is nested. This would result in data: 1) exposed to reader too early, 2) rolled back by other part of the transaction after such exposure So we need to end up in a situation where we call 'finalize' a single time when the transaction actually closes. For this purpose we need to be able to call 'delayupdate' and '_writepending' multiple times and 'finalize' once. This was not possible with the previous state of the code. This changeset refactors the code to makes this possible. We buffer data in memory as much as possible and fall-back to writing to a ".a" file after the first call to '_writepending'.
375 lines
13 KiB
Python
375 lines
13 KiB
Python
# changelog.py - changelog class for mercurial
|
|
#
|
|
# Copyright 2005-2007 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 node import bin, hex, nullid
|
|
from i18n import _
|
|
import util, error, revlog, encoding
|
|
|
|
_defaultextra = {'branch': 'default'}
|
|
|
|
def _string_escape(text):
|
|
"""
|
|
>>> d = {'nl': chr(10), 'bs': chr(92), 'cr': chr(13), 'nul': chr(0)}
|
|
>>> s = "ab%(nl)scd%(bs)s%(bs)sn%(nul)sab%(cr)scd%(bs)s%(nl)s" % d
|
|
>>> s
|
|
'ab\\ncd\\\\\\\\n\\x00ab\\rcd\\\\\\n'
|
|
>>> res = _string_escape(s)
|
|
>>> s == res.decode('string_escape')
|
|
True
|
|
"""
|
|
# subset of the string_escape codec
|
|
text = text.replace('\\', '\\\\').replace('\n', '\\n').replace('\r', '\\r')
|
|
return text.replace('\0', '\\0')
|
|
|
|
def decodeextra(text):
|
|
"""
|
|
>>> sorted(decodeextra(encodeextra({'foo': 'bar', 'baz': chr(0) + '2'})
|
|
... ).iteritems())
|
|
[('baz', '\\x002'), ('branch', 'default'), ('foo', 'bar')]
|
|
>>> sorted(decodeextra(encodeextra({'foo': 'bar',
|
|
... 'baz': chr(92) + chr(0) + '2'})
|
|
... ).iteritems())
|
|
[('baz', '\\\\\\x002'), ('branch', 'default'), ('foo', 'bar')]
|
|
"""
|
|
extra = _defaultextra.copy()
|
|
for l in text.split('\0'):
|
|
if l:
|
|
if '\\0' in l:
|
|
# fix up \0 without getting into trouble with \\0
|
|
l = l.replace('\\\\', '\\\\\n')
|
|
l = l.replace('\\0', '\0')
|
|
l = l.replace('\n', '')
|
|
k, v = l.decode('string_escape').split(':', 1)
|
|
extra[k] = v
|
|
return extra
|
|
|
|
def encodeextra(d):
|
|
# keys must be sorted to produce a deterministic changelog entry
|
|
items = [_string_escape('%s:%s' % (k, d[k])) for k in sorted(d)]
|
|
return "\0".join(items)
|
|
|
|
def stripdesc(desc):
|
|
"""strip trailing whitespace and leading and trailing empty lines"""
|
|
return '\n'.join([l.rstrip() for l in desc.splitlines()]).strip('\n')
|
|
|
|
class appender(object):
|
|
'''the changelog index must be updated last on disk, so we use this class
|
|
to delay writes to it'''
|
|
def __init__(self, vfs, name, mode, buf):
|
|
self.data = buf
|
|
fp = vfs(name, mode)
|
|
self.fp = fp
|
|
self.offset = fp.tell()
|
|
self.size = vfs.fstat(fp).st_size
|
|
|
|
def end(self):
|
|
return self.size + len("".join(self.data))
|
|
def tell(self):
|
|
return self.offset
|
|
def flush(self):
|
|
pass
|
|
def close(self):
|
|
self.fp.close()
|
|
|
|
def seek(self, offset, whence=0):
|
|
'''virtual file offset spans real file and data'''
|
|
if whence == 0:
|
|
self.offset = offset
|
|
elif whence == 1:
|
|
self.offset += offset
|
|
elif whence == 2:
|
|
self.offset = self.end() + offset
|
|
if self.offset < self.size:
|
|
self.fp.seek(self.offset)
|
|
|
|
def read(self, count=-1):
|
|
'''only trick here is reads that span real file and data'''
|
|
ret = ""
|
|
if self.offset < self.size:
|
|
s = self.fp.read(count)
|
|
ret = s
|
|
self.offset += len(s)
|
|
if count > 0:
|
|
count -= len(s)
|
|
if count != 0:
|
|
doff = self.offset - self.size
|
|
self.data.insert(0, "".join(self.data))
|
|
del self.data[1:]
|
|
s = self.data[0][doff:doff + count]
|
|
self.offset += len(s)
|
|
ret += s
|
|
return ret
|
|
|
|
def write(self, s):
|
|
self.data.append(str(s))
|
|
self.offset += len(s)
|
|
|
|
def _divertopener(opener, target):
|
|
"""build an opener that writes in 'target.a' instead of 'target'"""
|
|
def _divert(name, mode='r'):
|
|
if name != target:
|
|
return opener(name, mode)
|
|
return opener(name + ".a", mode)
|
|
return _divert
|
|
|
|
def _delayopener(opener, target, buf):
|
|
"""build an opener that stores chunks in 'buf' instead of 'target'"""
|
|
def _delay(name, mode='r'):
|
|
if name != target:
|
|
return opener(name, mode)
|
|
return appender(opener, name, mode, buf)
|
|
return _delay
|
|
|
|
class changelog(revlog.revlog):
|
|
def __init__(self, opener):
|
|
revlog.revlog.__init__(self, opener, "00changelog.i")
|
|
if self._initempty:
|
|
# changelogs don't benefit from generaldelta
|
|
self.version &= ~revlog.REVLOGGENERALDELTA
|
|
self._generaldelta = False
|
|
self._realopener = opener
|
|
self._delayed = False
|
|
self._delaybuf = None
|
|
self._divert = False
|
|
self.filteredrevs = frozenset()
|
|
|
|
def tip(self):
|
|
"""filtered version of revlog.tip"""
|
|
for i in xrange(len(self) -1, -2, -1):
|
|
if i not in self.filteredrevs:
|
|
return self.node(i)
|
|
|
|
def __iter__(self):
|
|
"""filtered version of revlog.__iter__"""
|
|
if len(self.filteredrevs) == 0:
|
|
return revlog.revlog.__iter__(self)
|
|
|
|
def filterediter():
|
|
for i in xrange(len(self)):
|
|
if i not in self.filteredrevs:
|
|
yield i
|
|
|
|
return filterediter()
|
|
|
|
def revs(self, start=0, stop=None):
|
|
"""filtered version of revlog.revs"""
|
|
for i in super(changelog, self).revs(start, stop):
|
|
if i not in self.filteredrevs:
|
|
yield i
|
|
|
|
@util.propertycache
|
|
def nodemap(self):
|
|
# XXX need filtering too
|
|
self.rev(self.node(0))
|
|
return self._nodecache
|
|
|
|
def hasnode(self, node):
|
|
"""filtered version of revlog.hasnode"""
|
|
try:
|
|
i = self.rev(node)
|
|
return i not in self.filteredrevs
|
|
except KeyError:
|
|
return False
|
|
|
|
def headrevs(self):
|
|
if self.filteredrevs:
|
|
try:
|
|
return self.index.headrevsfiltered(self.filteredrevs)
|
|
# AttributeError covers non-c-extension environments and
|
|
# old c extensions without filter handling.
|
|
except AttributeError:
|
|
return self._headrevs()
|
|
|
|
return super(changelog, self).headrevs()
|
|
|
|
def strip(self, *args, **kwargs):
|
|
# XXX make something better than assert
|
|
# We can't expect proper strip behavior if we are filtered.
|
|
assert not self.filteredrevs
|
|
super(changelog, self).strip(*args, **kwargs)
|
|
|
|
def rev(self, node):
|
|
"""filtered version of revlog.rev"""
|
|
r = super(changelog, self).rev(node)
|
|
if r in self.filteredrevs:
|
|
raise error.FilteredLookupError(hex(node), self.indexfile,
|
|
_('filtered node'))
|
|
return r
|
|
|
|
def node(self, rev):
|
|
"""filtered version of revlog.node"""
|
|
if rev in self.filteredrevs:
|
|
raise error.FilteredIndexError(rev)
|
|
return super(changelog, self).node(rev)
|
|
|
|
def linkrev(self, rev):
|
|
"""filtered version of revlog.linkrev"""
|
|
if rev in self.filteredrevs:
|
|
raise error.FilteredIndexError(rev)
|
|
return super(changelog, self).linkrev(rev)
|
|
|
|
def parentrevs(self, rev):
|
|
"""filtered version of revlog.parentrevs"""
|
|
if rev in self.filteredrevs:
|
|
raise error.FilteredIndexError(rev)
|
|
return super(changelog, self).parentrevs(rev)
|
|
|
|
def flags(self, rev):
|
|
"""filtered version of revlog.flags"""
|
|
if rev in self.filteredrevs:
|
|
raise error.FilteredIndexError(rev)
|
|
return super(changelog, self).flags(rev)
|
|
|
|
def delayupdate(self):
|
|
"delay visibility of index updates to other readers"
|
|
|
|
if not self._delayed:
|
|
if len(self) == 0:
|
|
self._divert = True
|
|
if self._realopener.exists(self.indexfile + '.a'):
|
|
self._realopener.unlink(self.indexfile + '.a')
|
|
self.opener = _divertopener(self._realopener, self.indexfile)
|
|
else:
|
|
self._delaybuf = []
|
|
self.opener = _delayopener(self._realopener, self.indexfile,
|
|
self._delaybuf)
|
|
self._delayed = True
|
|
|
|
def finalize(self, tr):
|
|
"finalize index updates"
|
|
self._delayed = False
|
|
self.opener = self._realopener
|
|
# move redirected index data back into place
|
|
if self._divert:
|
|
assert not self._delaybuf
|
|
tmpname = self.indexfile + ".a"
|
|
nfile = self.opener.open(tmpname)
|
|
nfile.close()
|
|
self.opener.rename(tmpname, self.indexfile)
|
|
elif self._delaybuf:
|
|
fp = self.opener(self.indexfile, 'a')
|
|
fp.write("".join(self._delaybuf))
|
|
fp.close()
|
|
self._delaybuf = None
|
|
self._divert = False
|
|
# split when we're done
|
|
self.checkinlinesize(tr)
|
|
|
|
def readpending(self, file):
|
|
r = revlog.revlog(self.opener, file)
|
|
self.index = r.index
|
|
self.nodemap = r.nodemap
|
|
self._nodecache = r._nodecache
|
|
self._chunkcache = r._chunkcache
|
|
|
|
def writepending(self):
|
|
"create a file containing the unfinalized state for pretxnchangegroup"
|
|
if self._delaybuf:
|
|
# make a temporary copy of the index
|
|
fp1 = self._realopener(self.indexfile)
|
|
fp2 = self._realopener(self.indexfile + ".a", "w")
|
|
fp2.write(fp1.read())
|
|
# add pending data
|
|
fp2.write("".join(self._delaybuf))
|
|
fp2.close()
|
|
# switch modes so finalize can simply rename
|
|
self._delaybuf = None
|
|
self._divert = True
|
|
self.opener = _divertopener(self._realopener, self.indexfile)
|
|
|
|
if self._divert:
|
|
return True
|
|
|
|
return False
|
|
|
|
def checkinlinesize(self, tr, fp=None):
|
|
if not self._delayed:
|
|
revlog.revlog.checkinlinesize(self, tr, fp)
|
|
|
|
def read(self, node):
|
|
"""
|
|
format used:
|
|
nodeid\n : manifest node in ascii
|
|
user\n : user, no \n or \r allowed
|
|
time tz extra\n : date (time is int or float, timezone is int)
|
|
: extra is metadata, encoded and separated by '\0'
|
|
: older versions ignore it
|
|
files\n\n : files modified by the cset, no \n or \r allowed
|
|
(.*) : comment (free text, ideally utf-8)
|
|
|
|
changelog v0 doesn't use extra
|
|
"""
|
|
text = self.revision(node)
|
|
if not text:
|
|
return (nullid, "", (0, 0), [], "", _defaultextra)
|
|
last = text.index("\n\n")
|
|
desc = encoding.tolocal(text[last + 2:])
|
|
l = text[:last].split('\n')
|
|
manifest = bin(l[0])
|
|
user = encoding.tolocal(l[1])
|
|
|
|
tdata = l[2].split(' ', 2)
|
|
if len(tdata) != 3:
|
|
time = float(tdata[0])
|
|
try:
|
|
# various tools did silly things with the time zone field.
|
|
timezone = int(tdata[1])
|
|
except ValueError:
|
|
timezone = 0
|
|
extra = _defaultextra
|
|
else:
|
|
time, timezone = float(tdata[0]), int(tdata[1])
|
|
extra = decodeextra(tdata[2])
|
|
|
|
files = l[3:]
|
|
return (manifest, user, (time, timezone), files, desc, extra)
|
|
|
|
def add(self, manifest, files, desc, transaction, p1, p2,
|
|
user, date=None, extra=None):
|
|
# Convert to UTF-8 encoded bytestrings as the very first
|
|
# thing: calling any method on a localstr object will turn it
|
|
# into a str object and the cached UTF-8 string is thus lost.
|
|
user, desc = encoding.fromlocal(user), encoding.fromlocal(desc)
|
|
|
|
user = user.strip()
|
|
# An empty username or a username with a "\n" will make the
|
|
# revision text contain two "\n\n" sequences -> corrupt
|
|
# repository since read cannot unpack the revision.
|
|
if not user:
|
|
raise error.RevlogError(_("empty username"))
|
|
if "\n" in user:
|
|
raise error.RevlogError(_("username %s contains a newline")
|
|
% repr(user))
|
|
|
|
desc = stripdesc(desc)
|
|
|
|
if date:
|
|
parseddate = "%d %d" % util.parsedate(date)
|
|
else:
|
|
parseddate = "%d %d" % util.makedate()
|
|
if extra:
|
|
branch = extra.get("branch")
|
|
if branch in ("default", ""):
|
|
del extra["branch"]
|
|
elif branch in (".", "null", "tip"):
|
|
raise error.RevlogError(_('the name \'%s\' is reserved')
|
|
% branch)
|
|
if extra:
|
|
extra = encodeextra(extra)
|
|
parseddate = "%s %s" % (parseddate, extra)
|
|
l = [hex(manifest), user, parseddate] + sorted(files) + ["", desc]
|
|
text = "\n".join(l)
|
|
return self.addrevision(text, transaction, len(self), p1, p2)
|
|
|
|
def branchinfo(self, rev):
|
|
"""return the branch name and open/close state of a revision
|
|
|
|
This function exists because creating a changectx object
|
|
just to access this is costly."""
|
|
extra = self.read(rev)[5]
|
|
return encoding.tolocal(extra.get("branch")), 'close' in extra
|