ref: 19cc46bc5ee1dd43537c4094d19d8da778b72bce
dir: /sys/lib/python/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)