ref: 2aec1f8a09ae0bc9fb269d84ef53defebc47eede
dir: /sys/src/cmd/hg/mercurial/changelog.py/
# 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, incorporated herein by reference.
from node import bin, hex, nullid
from i18n import _
import util, error, revlog, encoding
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):
extra = {}
for l in text.split('\0'):
if l:
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)
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, fp, buf):
self.data = buf
self.fp = fp
self.offset = fp.tell()
self.size = util.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 delayopener(opener, target, divert, buf):
def o(name, mode='r'):
if name != target:
return opener(name, mode)
if divert:
return opener(name + ".a", mode.replace('a', 'w'))
# otherwise, divert to memory
return appender(opener(name, mode), buf)
return o
class changelog(revlog.revlog):
def __init__(self, opener):
revlog.revlog.__init__(self, opener, "00changelog.i")
self._realopener = opener
self._delayed = False
self._divert = False
def delayupdate(self):
"delay visibility of index updates to other readers"
self._delayed = True
self._divert = (len(self) == 0)
self._delaybuf = []
self.opener = delayopener(self._realopener, self.indexfile,
self._divert, self._delaybuf)
def finalize(self, tr):
"finalize index updates"
self._delayed = False
self.opener = self._realopener
# move redirected index data back into place
if self._divert:
n = self.opener(self.indexfile + ".a").name
util.rename(n, n[:-2])
elif self._delaybuf:
fp = self.opener(self.indexfile, 'a')
fp.write("".join(self._delaybuf))
fp.close()
self._delaybuf = []
# 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._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 = []
self._divert = True
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 metadatas, 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), [], "", {'branch': 'default'})
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])
extra_data = l[2].split(' ', 2)
if len(extra_data) != 3:
time = float(extra_data.pop(0))
try:
# various tools did silly things with the time zone field.
timezone = int(extra_data[0])
except:
timezone = 0
extra = {}
else:
time, timezone, extra = extra_data
time, timezone = float(time), int(timezone)
extra = decodeextra(extra)
if not extra.get('branch'):
extra['branch'] = 'default'
files = l[3:]
return (manifest, user, (time, timezone), files, desc, extra)
def add(self, manifest, files, desc, transaction, p1, p2,
user, date=None, extra={}):
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))
# strip trailing whitespace and leading and trailing empty lines
desc = '\n'.join([l.rstrip() for l in desc.splitlines()]).strip('\n')
user, desc = encoding.fromlocal(user), encoding.fromlocal(desc)
if date:
parseddate = "%d %d" % util.parsedate(date)
else:
parseddate = "%d %d" % util.makedate()
if extra and extra.get("branch") in ("default", ""):
del extra["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)