Mercurial > hg
view mercurial/config.py @ 26402:05871262acd5
treemanifest: rework lazy-copying code (issue4840)
The old lazy-copy code formed a chain of copied manifests with each
copy. Under typical operation, the stack never got more than a couple
of manifests deep and was fine. Under conditions like hgsubversion or
convert, the stack could get hundreds of manifests deep, and
eventually overflow the recursion limit for Python. I was able to
consistently reproduce this by converting an hgsubversion clone of
svn's history to treemanifests.
This may result in fewer manifests staying in memory during operations
like convert when treemanifests are in use, and should make those
operations faster since there will be significantly fewer noop
function calls going on.
A previous attempt (never mailed) of mine to fix this problem tried to
simply have all treemanifests only have a loadfunc - that caused
somewhat weird problems because the gettext() callable passed into
read() wasn't idempotent, so the easy solution is to have a loadfunc
and a copyfunc.
author | Augie Fackler <augie@google.com> |
---|---|
date | Fri, 25 Sep 2015 22:54:46 -0400 |
parents | a027a0813b44 |
children | e70c97cc9243 |
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# config.py - configuration parsing for Mercurial # # Copyright 2009 Matt Mackall <mpm@selenic.com> and others # # This software may be used and distributed according to the terms of the # GNU General Public License version 2 or any later version. from __future__ import absolute_import import errno import os from .i18n import _ from . import ( error, util, ) class config(object): def __init__(self, data=None, includepaths=[]): self._data = {} self._source = {} self._unset = [] self._includepaths = includepaths if data: for k in data._data: self._data[k] = data[k].copy() self._source = data._source.copy() def copy(self): return config(self) def __contains__(self, section): return section in self._data def __getitem__(self, section): return self._data.get(section, {}) def __iter__(self): for d in self.sections(): yield d def update(self, src): for s, n in src._unset: if s in self and n in self._data[s]: del self._data[s][n] del self._source[(s, n)] for s in src: if s not in self: self._data[s] = util.sortdict() self._data[s].update(src._data[s]) self._source.update(src._source) def get(self, section, item, default=None): return self._data.get(section, {}).get(item, default) def backup(self, section, item): """return a tuple allowing restore to reinstall a previous value The main reason we need it is because it handles the "no data" case. """ try: value = self._data[section][item] source = self.source(section, item) return (section, item, value, source) except KeyError: return (section, item) def source(self, section, item): return self._source.get((section, item), "") def sections(self): return sorted(self._data.keys()) def items(self, section): return self._data.get(section, {}).items() def set(self, section, item, value, source=""): if section not in self: self._data[section] = util.sortdict() self._data[section][item] = value if source: self._source[(section, item)] = source def restore(self, data): """restore data returned by self.backup""" if len(data) == 4: # restore old data section, item, value, source = data self._data[section][item] = value self._source[(section, item)] = source else: # no data before, remove everything section, item = data if section in self._data: self._data[section].pop(item, None) self._source.pop((section, item), None) def parse(self, src, data, sections=None, remap=None, include=None): sectionre = util.re.compile(r'\[([^\[]+)\]') itemre = util.re.compile(r'([^=\s][^=]*?)\s*=\s*(.*\S|)') contre = util.re.compile(r'\s+(\S|\S.*\S)\s*$') emptyre = util.re.compile(r'(;|#|\s*$)') commentre = util.re.compile(r'(;|#)') unsetre = util.re.compile(r'%unset\s+(\S+)') includere = util.re.compile(r'%include\s+(\S|\S.*\S)\s*$') section = "" item = None line = 0 cont = False for l in data.splitlines(True): line += 1 if line == 1 and l.startswith('\xef\xbb\xbf'): # Someone set us up the BOM l = l[3:] if cont: if commentre.match(l): continue m = contre.match(l) if m: if sections and section not in sections: continue v = self.get(section, item) + "\n" + m.group(1) self.set(section, item, v, "%s:%d" % (src, line)) continue item = None cont = False m = includere.match(l) if m and include: expanded = util.expandpath(m.group(1)) includepaths = [os.path.dirname(src)] + self._includepaths for base in includepaths: inc = os.path.normpath(os.path.join(base, expanded)) try: include(inc, remap=remap, sections=sections) break except IOError as inst: if inst.errno != errno.ENOENT: raise error.ParseError(_("cannot include %s (%s)") % (inc, inst.strerror), "%s:%s" % (src, line)) continue if emptyre.match(l): continue m = sectionre.match(l) if m: section = m.group(1) if remap: section = remap.get(section, section) if section not in self: self._data[section] = util.sortdict() continue m = itemre.match(l) if m: item = m.group(1) cont = True if sections and section not in sections: continue self.set(section, item, m.group(2), "%s:%d" % (src, line)) continue m = unsetre.match(l) if m: name = m.group(1) if sections and section not in sections: continue if self.get(section, name) is not None: del self._data[section][name] self._unset.append((section, name)) continue raise error.ParseError(l.rstrip(), ("%s:%s" % (src, line))) def read(self, path, fp=None, sections=None, remap=None): if not fp: fp = util.posixfile(path) self.parse(path, fp.read(), sections, remap, self.read)