##// END OF EJS Templates
ssh: avoid reading beyond the end of stream when using compression...
ssh: avoid reading beyond the end of stream when using compression Compressed streams can be used as part of getbundle. The normal read() operation of bufferedinputpipe will try to fulfill the request exactly and can deadlock if the server sends less as it is done. At the same time, the bundle2 logic will stop reading when it believes it has gotten all parts of the bundle, which can leave behind end of stream markers as used by bzip2 and zstd. To solve this, introduce a new optional unbufferedread interface and provided it in bufferedinputpipe and doublepipe. If there is buffered data left, it will be returned, otherwise it will issue a single read request and return whatever it obtains. Reorganize the decompression handlers to try harder to read until the end of stream, especially if the requested read can already be fulfilled. Check for end of stream is messy with Python 2, none of the standard compression modules properly exposes it. At least with zstd and bzip2, decompressing will remember EOS and fail for empty input after the EOS has been seen. For zlib, the only way to detect it with Python 2 is to duplicate the decompressobj and force some additional data into it. The common handler can be further optimized, but works as PoC. Differential Revision: https://phab.mercurial-scm.org/D3937

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__init__.py
93 lines | 3.1 KiB | text/x-python | PythonLexer
# __init__.py - narrowhg extension
#
# Copyright 2017 Google, Inc.
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.
'''create clones which fetch history data for subset of files (EXPERIMENTAL)'''
from __future__ import absolute_import
# Note for extension authors: ONLY specify testedwith = 'ships-with-hg-core' for
# extensions which SHIP WITH MERCURIAL. Non-mainline extensions should
# be specifying the version(s) of Mercurial they are tested with, or
# leave the attribute unspecified.
testedwith = 'ships-with-hg-core'
from mercurial import (
changegroup,
extensions,
hg,
localrepo,
registrar,
verify as verifymod,
)
from . import (
narrowbundle2,
narrowchangegroup,
narrowcommands,
narrowcopies,
narrowpatch,
narrowrepo,
narrowrevlog,
narrowtemplates,
narrowwirepeer,
)
configtable = {}
configitem = registrar.configitem(configtable)
# Narrowhg *has* support for serving ellipsis nodes (which are used at
# least by Google's internal server), but that support is pretty
# fragile and has a lot of problems on real-world repositories that
# have complex graph topologies. This could probably be corrected, but
# absent someone needing the full support for ellipsis nodes in
# repositories with merges, it's unlikely this work will get done. As
# of this writining in late 2017, all repositories large enough for
# ellipsis nodes to be a hard requirement also enforce strictly linear
# history for other scaling reasons.
configitem('experimental', 'narrowservebrokenellipses',
default=False,
alias=[('narrow', 'serveellipses')],
)
# Export the commands table for Mercurial to see.
cmdtable = narrowcommands.table
def featuresetup(ui, features):
features.add(changegroup.NARROW_REQUIREMENT)
def uisetup(ui):
"""Wraps user-facing mercurial commands with narrow-aware versions."""
localrepo.featuresetupfuncs.add(featuresetup)
narrowrevlog.setup()
narrowbundle2.setup()
narrowcommands.setup()
narrowchangegroup.setup()
narrowwirepeer.uisetup()
def reposetup(ui, repo):
"""Wraps local repositories with narrow repo support."""
if not repo.local():
return
if changegroup.NARROW_REQUIREMENT in repo.requirements:
narrowrepo.wraprepo(repo)
narrowcopies.setup(repo)
narrowpatch.setup(repo)
narrowwirepeer.reposetup(repo)
def _verifierinit(orig, self, repo, matcher=None):
# The verifier's matcher argument was desgined for narrowhg, so it should
# be None from core. If another extension passes a matcher (unlikely),
# we'll have to fail until matchers can be composed more easily.
assert matcher is None
orig(self, repo, repo.narrowmatch())
def extsetup(ui):
extensions.wrapfunction(verifymod.verifier, '__init__', _verifierinit)
extensions.wrapfunction(hg, 'postshare', narrowrepo.wrappostshare)
extensions.wrapfunction(hg, 'copystore', narrowrepo.unsharenarrowspec)
templatekeyword = narrowtemplates.templatekeyword
revsetpredicate = narrowtemplates.revsetpredicate