mercurial/streamclone.py

merge: fix --preview to show all nodes that will be merged (issue2043).

Formerly, it omitted nodes that were not descendants of the least
common ancestor of the two merge parents, even though those nodes
contribute to the merge.  The new algorithm uses revlog.findmissing()
instead of ancestor() + nodesbetween().

# streamclone.py - streaming clone server support for mercurial
#
# Copyright 2006 Vadim Gelfer <[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.

import util, error
from i18n import _

from mercurial import store

class StreamException(Exception):
    def __init__(self, code):
        Exception.__init__(self)
        self.code = code
    def __str__(self):
        return '%i\n' % self.code

# if server supports streaming clone, it advertises "stream"
# capability with value that is version+flags of repo it is serving.
# client only streams if it can read that repo format.

# stream file format is simple.
#
# server writes out line that says how many files, how many total
# bytes.  separator is ascii space, byte counts are strings.
#
# then for each file:
#
#   server writes out line that says filename, how many bytes in
#   file.  separator is ascii nul, byte count is string.
#
#   server writes out raw file data.

def allowed(ui):
    return ui.configbool('server', 'uncompressed', True, untrusted=True)

def stream_out(repo):
    '''stream out all metadata files in repository.
    writes to file-like object, must support write() and optional flush().'''

    if not allowed(repo.ui):
        raise StreamException(1)

    entries = []
    total_bytes = 0
    try:
        # get consistent snapshot of repo, lock during scan
        lock = repo.lock()
        try:
            repo.ui.debug('scanning\n')
            for name, ename, size in repo.store.walk():
                entries.append((name, size))
                total_bytes += size
        finally:
            lock.release()
    except error.LockError:
        raise StreamException(2)

    yield '0\n'
    repo.ui.debug('%d files, %d bytes to transfer\n' %
                  (len(entries), total_bytes))
    yield '%d %d\n' % (len(entries), total_bytes)
    for name, size in entries:
        repo.ui.debug('sending %s (%d bytes)\n' % (name, size))
        # partially encode name over the wire for backwards compat
        yield '%s\0%d\n' % (store.encodedir(name), size)
        for chunk in util.filechunkiter(repo.sopener(name), limit=size):
            yield chunk