manifest/revlog: do not let the revlog cache mutable objects
If a buffer of an mutable object is passed to revlog.addrevision(), the revlog
will happily store it in its cache. Later when the revlog reuses the cached
entry, if the manifest modified the object in-between, all kind of bugs
appears.
We fix it by:
- passing immutable objects to addrevision() if they are already available
- only storing the text in the cache if it's of str type
Then we can remove the conversion of the cache entry to str() during
retrieval. That was probably just there hiding the bug for the common cases
but not really fixing it.
# filelog.py - file history 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.
import revlog
class filelog(revlog.revlog):
def __init__(self, opener, path):
revlog.revlog.__init__(self, opener,
"/".join(("data", path + ".i")))
def read(self, node):
t = self.revision(node)
if not t.startswith('\1\n'):
return t
s = t.index('\1\n', 2)
return t[s+2:]
def _readmeta(self, node):
t = self.revision(node)
if not t.startswith('\1\n'):
return {}
s = t.index('\1\n', 2)
mt = t[2:s]
m = {}
for l in mt.splitlines():
k, v = l.split(": ", 1)
m[k] = v
return m
def add(self, text, meta, transaction, link, p1=None, p2=None):
if meta or text.startswith('\1\n'):
mt = ""
if meta:
mt = ["%s: %s\n" % (k, v) for k, v in meta.iteritems()]
text = "\1\n%s\1\n%s" % ("".join(mt), text)
return self.addrevision(text, transaction, link, p1, p2)
def renamed(self, node):
if self.parents(node)[0] != revlog.nullid:
return False
m = self._readmeta(node)
if m and "copy" in m:
return (m["copy"], revlog.bin(m["copyrev"]))
return False
def size(self, rev):
"""return the size of a given revision"""
# for revisions with renames, we have to go the slow way
node = self.node(rev)
if self.renamed(node):
return len(self.read(node))
return revlog.revlog.size(self, rev)
def cmp(self, node, text):
"""compare text with a given file revision"""
# for renames, we have to go the slow way
if self.renamed(node):
t2 = self.read(node)
return t2 != text
return revlog.revlog.cmp(self, node, text)