hgext/largefiles/remotestore.py

subrepo: fix for merge inconsistencies

Merging ancestors with children is allowed if they are on different
named branches. This did not work for subrepo merges before. To fix
this inconsistency, the mergefunc() will now use the simple update
path only if both versions are on the same named branch. If not, they
get merged into a new changeset, just as if you did the merge from the
subrepo's root directly.

# Copyright 2010-2011 Fog Creek Software
# Copyright 2010-2011 Unity Technologies
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

'''remote largefile store; the base class for servestore'''

import urllib2

from mercurial import util
from mercurial.i18n import _

import lfutil
import basestore

class remotestore(basestore.basestore):
    '''a largefile store accessed over a network'''
    def __init__(self, ui, repo, url):
        super(remotestore, self).__init__(ui, repo, url)

    def put(self, source, hash):
        if self._verify(hash):
            return
        if self.sendfile(source, hash):
            raise util.Abort(
                _('remotestore: could not put %s to remote store %s')
                % (source, self.url))
        self.ui.debug(
            _('remotestore: put %s to remote store %s') % (source, self.url))

    def exists(self, hash):
        return self._verify(hash)

    def sendfile(self, filename, hash):
        self.ui.debug('remotestore: sendfile(%s, %s)\n' % (filename, hash))
        fd = None
        try:
            try:
                fd = lfutil.httpsendfile(self.ui, filename)
            except IOError, e:
                raise util.Abort(
                    _('remotestore: could not open file %s: %s')
                    % (filename, str(e)))
            return self._put(hash, fd)
        finally:
            if fd:
                fd.close()

    def _getfile(self, tmpfile, filename, hash):
        # quit if the largefile isn't there
        stat = self._stat(hash)
        if stat == 1:
            raise util.Abort(_('remotestore: largefile %s is invalid') % hash)
        elif stat == 2:
            raise util.Abort(_('remotestore: largefile %s is missing') % hash)

        try:
            length, infile = self._get(hash)
        except urllib2.HTTPError, e:
            # 401s get converted to util.Aborts; everything else is fine being
            # turned into a StoreError
            raise basestore.StoreError(filename, hash, self.url, str(e))
        except urllib2.URLError, e:
            # This usually indicates a connection problem, so don't
            # keep trying with the other files... they will probably
            # all fail too.
            raise util.Abort('%s: %s' % (self.url, e.reason))
        except IOError, e:
            raise basestore.StoreError(filename, hash, self.url, str(e))

        # Mercurial does not close its SSH connections after writing a stream
        if length is not None:
            infile = lfutil.limitreader(infile, length)
        return lfutil.copyandhash(lfutil.blockstream(infile), tmpfile)

    def _verify(self, hash):
        return not self._stat(hash)

    def _verifyfile(self, cctx, cset, contents, standin, verified):
        filename = lfutil.splitstandin(standin)
        if not filename:
            return False
        fctx = cctx[standin]
        key = (filename, fctx.filenode())
        if key in verified:
            return False

        verified.add(key)

        stat = self._stat(hash)
        if not stat:
            return False
        elif stat == 1:
            self.ui.warn(
                _('changeset %s: %s: contents differ\n')
                % (cset, filename))
            return True # failed
        elif stat == 2:
            self.ui.warn(
                _('changeset %s: %s missing\n')
                % (cset, filename))
            return True # failed
        else:
            raise RuntimeError('verify failed: unexpected response from '
                               'statlfile (%r)' % stat)