view mercurial/hgweb/__init__.py @ 29014:f1ca249696ed stable

bdiff: balance recursion to avoid quadratic behavior (issue4704)

For highly structured files like JSON or XML dumps with large numbers
of duplicate lines (eg braces) and isolated matching lines, bdiff
could find large numbers of equally good spans. Because it prefers
earlier matches, this would result in pathologically unbalance
recursion that resulted in quadratic performance.

This patch makes it prefer matches closer to the middle that tend to
balance recursion. This change improves the speed of a pathological
test case from 1100s to 9s.

Included is a smaller test that has a roughly 50x safety margin on the
performance it accepts. It's likely to fail on pure builds because
difflib also has a recursion-balancing problem.

# hgweb/__init__.py - web interface to a mercurial repository
#
# Copyright 21 May 2005 - (c) 2005 Jake Edge <[e-mail]>
# Copyright 2005 Matt Mackall <[e-mail]>
#
# 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 os

from ..i18n import _

from .. import (
    error,
    util,
)

from . import (
    hgweb_mod,
    hgwebdir_mod,
    server,
)

def hgweb(config, name=None, baseui=None):
    '''create an hgweb wsgi object

    config can be one of:
    - repo object (single repo view)
    - path to repo (single repo view)
    - path to config file (multi-repo view)
    - dict of virtual:real pairs (multi-repo view)
    - list of virtual:real tuples (multi-repo view)
    '''

    if ((isinstance(config, str) and not os.path.isdir(config)) or
        isinstance(config, dict) or isinstance(config, list)):
        # create a multi-dir interface
        return hgwebdir_mod.hgwebdir(config, baseui=baseui)
    return hgweb_mod.hgweb(config, name=name, baseui=baseui)

def hgwebdir(config, baseui=None):
    return hgwebdir_mod.hgwebdir(config, baseui=baseui)

class httpservice(object):
    def __init__(self, ui, app, opts):
        self.ui = ui
        self.app = app
        self.opts = opts

    def init(self):
        util.setsignalhandler()
        self.httpd = server.create_server(self.ui, self.app)

        if self.opts['port'] and not self.ui.verbose:
            return

        if self.httpd.prefix:
            prefix = self.httpd.prefix.strip('/') + '/'
        else:
            prefix = ''

        port = ':%d' % self.httpd.port
        if port == ':80':
            port = ''

        bindaddr = self.httpd.addr
        if bindaddr == '0.0.0.0':
            bindaddr = '*'
        elif ':' in bindaddr: # IPv6
            bindaddr = '[%s]' % bindaddr

        fqaddr = self.httpd.fqaddr
        if ':' in fqaddr:
            fqaddr = '[%s]' % fqaddr
        if self.opts['port']:
            write = self.ui.status
        else:
            write = self.ui.write
        write(_('listening at http://%s%s/%s (bound to %s:%d)\n') %
              (fqaddr, port, prefix, bindaddr, self.httpd.port))
        self.ui.flush()  # avoid buffering of status message

    def run(self):
        self.httpd.serve_forever()

def createservice(ui, repo, opts):
    # this way we can check if something was given in the command-line
    if opts.get('port'):
        opts['port'] = util.getport(opts.get('port'))

    alluis = set([ui])
    if repo:
        baseui = repo.baseui
        alluis.update([repo.baseui, repo.ui])
    else:
        baseui = ui
    webconf = opts.get('web_conf') or opts.get('webdir_conf')
    if webconf:
        # load server settings (e.g. web.port) to "copied" ui, which allows
        # hgwebdir to reload webconf cleanly
        servui = ui.copy()
        servui.readconfig(webconf, sections=['web'])
        alluis.add(servui)
    else:
        servui = ui

    optlist = ("name templates style address port prefix ipv6"
               " accesslog errorlog certificate encoding")
    for o in optlist.split():
        val = opts.get(o, '')
        if val in (None, ''): # should check against default options instead
            continue
        for u in alluis:
            u.setconfig("web", o, val, 'serve')

    if webconf:
        app = hgwebdir_mod.hgwebdir(webconf, baseui=baseui)
    else:
        if not repo:
            raise error.RepoError(_("there is no Mercurial repository"
                                    " here (.hg not found)"))
        app = hgweb_mod.hgweb(repo, baseui=baseui)
    return httpservice(servui, app, opts)