cmdutil: convert _revertprefetch() to a generic stored file hook (API)
This will be used by LFS to fetch required files in a group for multiple
commands, prior to being accessed. That avoids the one-at-a-time fetch when the
filelog wrapper goes to access it, and it is missing locally (which costs two
round trips to the server.) The core command list that needs this is probably
at least:
- annotate
- archive (which is also used by extdiff)
- cat
- diff
- export
- grep
- verify (sadly)
- anything that has the '{data}' template
There are no core users of the revert prefetch hook, and never have been since
it was introduced in
45e02cfad4bd for remotefilelog. Thanks to Yuya for
figuring out a way to reliably trigger the deprecated warning. Unfortunately,
it wanted to blame the caller of revert. Passing along an adjusted stack level
seemed the least bad choice (although it still blames a core function).
One thing to note is that the store lock isn't being held when this is called.
I'm not at all familiar with remotefilelog or its locking requirements, so this
may not be a big deal. Currently, LFS doesn't hold a lock when downloading
files. Even though largefiles doesn't either, I'm starting to think it should,
and maybe the .hg/store/lock isn't good enough to cover the globally shared
cache.
.. api::
The cmdutil._revertprefetch() hook point for prefetching stored files has
been replaced by the command agnostic cmdutil._prefetchfiles(). The new
function takes a list of files, instead of a list of lists of files.
# sshpeer.py - ssh repository proxy class for mercurial
#
# Copyright 2005, 2006 Matt Mackall <mpm@selenic.com>
#
# 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 re
from .i18n import _
from . import (
error,
pycompat,
util,
wireproto,
)
def _serverquote(s):
"""quote a string for the remote shell ... which we assume is sh"""
if not s:
return s
if re.match('[a-zA-Z0-9@%_+=:,./-]*$', s):
return s
return "'%s'" % s.replace("'", "'\\''")
def _forwardoutput(ui, pipe):
"""display all data currently available on pipe as remote output.
This is non blocking."""
s = util.readpipe(pipe)
if s:
for l in s.splitlines():
ui.status(_("remote: "), l, '\n')
class doublepipe(object):
"""Operate a side-channel pipe in addition of a main one
The side-channel pipe contains server output to be forwarded to the user
input. The double pipe will behave as the "main" pipe, but will ensure the
content of the "side" pipe is properly processed while we wait for blocking
call on the "main" pipe.
If large amounts of data are read from "main", the forward will cease after
the first bytes start to appear. This simplifies the implementation
without affecting actual output of sshpeer too much as we rarely issue
large read for data not yet emitted by the server.
The main pipe is expected to be a 'bufferedinputpipe' from the util module
that handle all the os specific bits. This class lives in this module
because it focus on behavior specific to the ssh protocol."""
def __init__(self, ui, main, side):
self._ui = ui
self._main = main
self._side = side
def _wait(self):
"""wait until some data are available on main or side
return a pair of boolean (ismainready, issideready)
(This will only wait for data if the setup is supported by `util.poll`)
"""
if getattr(self._main, 'hasbuffer', False): # getattr for classic pipe
return (True, True) # main has data, assume side is worth poking at.
fds = [self._main.fileno(), self._side.fileno()]
try:
act = util.poll(fds)
except NotImplementedError:
# non supported yet case, assume all have data.
act = fds
return (self._main.fileno() in act, self._side.fileno() in act)
def write(self, data):
return self._call('write', data)
def read(self, size):
r = self._call('read', size)
if size != 0 and not r:
# We've observed a condition that indicates the
# stdout closed unexpectedly. Check stderr one
# more time and snag anything that's there before
# letting anyone know the main part of the pipe
# closed prematurely.
_forwardoutput(self._ui, self._side)
return r
def readline(self):
return self._call('readline')
def _call(self, methname, data=None):
"""call <methname> on "main", forward output of "side" while blocking
"""
# data can be '' or 0
if (data is not None and not data) or self._main.closed:
_forwardoutput(self._ui, self._side)
return ''
while True:
mainready, sideready = self._wait()
if sideready:
_forwardoutput(self._ui, self._side)
if mainready:
meth = getattr(self._main, methname)
if data is None:
return meth()
else:
return meth(data)
def close(self):
return self._main.close()
def flush(self):
return self._main.flush()
class sshpeer(wireproto.wirepeer):
def __init__(self, ui, path, create=False):
self._url = path
self._ui = ui
self._pipeo = self._pipei = self._pipee = None
u = util.url(path, parsequery=False, parsefragment=False)
if u.scheme != 'ssh' or not u.host or u.path is None:
self._abort(error.RepoError(_("couldn't parse location %s") % path))
util.checksafessh(path)
if u.passwd is not None:
self._abort(error.RepoError(_("password in URL not supported")))
self._user = u.user
self._host = u.host
self._port = u.port
self._path = u.path or '.'
sshcmd = self.ui.config("ui", "ssh")
remotecmd = self.ui.config("ui", "remotecmd")
sshaddenv = dict(self.ui.configitems("sshenv"))
sshenv = util.shellenviron(sshaddenv)
args = util.sshargs(sshcmd, self._host, self._user, self._port)
if create:
cmd = '%s %s %s' % (sshcmd, args,
util.shellquote("%s init %s" %
(_serverquote(remotecmd), _serverquote(self._path))))
ui.debug('running %s\n' % cmd)
res = ui.system(cmd, blockedtag='sshpeer', environ=sshenv)
if res != 0:
self._abort(error.RepoError(_("could not create remote repo")))
self._validaterepo(sshcmd, args, remotecmd, sshenv)
# Begin of _basepeer interface.
@util.propertycache
def ui(self):
return self._ui
def url(self):
return self._url
def local(self):
return None
def peer(self):
return self
def canpush(self):
return True
def close(self):
pass
# End of _basepeer interface.
# Begin of _basewirecommands interface.
def capabilities(self):
return self._caps
# End of _basewirecommands interface.
def _validaterepo(self, sshcmd, args, remotecmd, sshenv=None):
# cleanup up previous run
self._cleanup()
cmd = '%s %s %s' % (sshcmd, args,
util.shellquote("%s -R %s serve --stdio" %
(_serverquote(remotecmd), _serverquote(self._path))))
self.ui.debug('running %s\n' % cmd)
cmd = util.quotecommand(cmd)
# while self._subprocess isn't used, having it allows the subprocess to
# to clean up correctly later
#
# no buffer allow the use of 'select'
# feel free to remove buffering and select usage when we ultimately
# move to threading.
sub = util.popen4(cmd, bufsize=0, env=sshenv)
self._pipeo, self._pipei, self._pipee, self._subprocess = sub
self._pipei = util.bufferedinputpipe(self._pipei)
self._pipei = doublepipe(self.ui, self._pipei, self._pipee)
self._pipeo = doublepipe(self.ui, self._pipeo, self._pipee)
def badresponse():
msg = _("no suitable response from remote hg")
hint = self.ui.config("ui", "ssherrorhint")
self._abort(error.RepoError(msg, hint=hint))
try:
# skip any noise generated by remote shell
self._callstream("hello")
r = self._callstream("between", pairs=("%s-%s" % ("0"*40, "0"*40)))
except IOError:
badresponse()
lines = ["", "dummy"]
max_noise = 500
while lines[-1] and max_noise:
try:
l = r.readline()
self._readerr()
if lines[-1] == "1\n" and l == "\n":
break
if l:
self.ui.debug("remote: ", l)
lines.append(l)
max_noise -= 1
except IOError:
badresponse()
else:
badresponse()
self._caps = set()
for l in reversed(lines):
if l.startswith("capabilities:"):
self._caps.update(l[:-1].split(":")[1].split())
break
def _readerr(self):
_forwardoutput(self.ui, self._pipee)
def _abort(self, exception):
self._cleanup()
raise exception
def _cleanup(self):
if self._pipeo is None:
return
self._pipeo.close()
self._pipei.close()
try:
# read the error descriptor until EOF
for l in self._pipee:
self.ui.status(_("remote: "), l)
except (IOError, ValueError):
pass
self._pipee.close()
__del__ = _cleanup
def _submitbatch(self, req):
rsp = self._callstream("batch", cmds=wireproto.encodebatchcmds(req))
available = self._getamount()
# TODO this response parsing is probably suboptimal for large
# batches with large responses.
toread = min(available, 1024)
work = rsp.read(toread)
available -= toread
chunk = work
while chunk:
while ';' in work:
one, work = work.split(';', 1)
yield wireproto.unescapearg(one)
toread = min(available, 1024)
chunk = rsp.read(toread)
available -= toread
work += chunk
yield wireproto.unescapearg(work)
def _callstream(self, cmd, **args):
args = pycompat.byteskwargs(args)
if (self.ui.debugflag
and self.ui.configbool('devel', 'debug.peer-request')):
dbg = self.ui.debug
line = 'devel-peer-request: %s\n'
dbg(line % cmd)
for key, value in sorted(args.items()):
if not isinstance(value, dict):
dbg(line % ' %s: %d bytes' % (key, len(value)))
else:
for dk, dv in sorted(value.items()):
dbg(line % ' %s-%s: %d' % (key, dk, len(dv)))
self.ui.debug("sending %s command\n" % cmd)
self._pipeo.write("%s\n" % cmd)
_func, names = wireproto.commands[cmd]
keys = names.split()
wireargs = {}
for k in keys:
if k == '*':
wireargs['*'] = args
break
else:
wireargs[k] = args[k]
del args[k]
for k, v in sorted(wireargs.iteritems()):
self._pipeo.write("%s %d\n" % (k, len(v)))
if isinstance(v, dict):
for dk, dv in v.iteritems():
self._pipeo.write("%s %d\n" % (dk, len(dv)))
self._pipeo.write(dv)
else:
self._pipeo.write(v)
self._pipeo.flush()
return self._pipei
def _callcompressable(self, cmd, **args):
return self._callstream(cmd, **args)
def _call(self, cmd, **args):
self._callstream(cmd, **args)
return self._recv()
def _callpush(self, cmd, fp, **args):
r = self._call(cmd, **args)
if r:
return '', r
for d in iter(lambda: fp.read(4096), ''):
self._send(d)
self._send("", flush=True)
r = self._recv()
if r:
return '', r
return self._recv(), ''
def _calltwowaystream(self, cmd, fp, **args):
r = self._call(cmd, **args)
if r:
# XXX needs to be made better
raise error.Abort(_('unexpected remote reply: %s') % r)
for d in iter(lambda: fp.read(4096), ''):
self._send(d)
self._send("", flush=True)
return self._pipei
def _getamount(self):
l = self._pipei.readline()
if l == '\n':
self._readerr()
msg = _('check previous remote output')
self._abort(error.OutOfBandError(hint=msg))
self._readerr()
try:
return int(l)
except ValueError:
self._abort(error.ResponseError(_("unexpected response:"), l))
def _recv(self):
return self._pipei.read(self._getamount())
def _send(self, data, flush=False):
self._pipeo.write("%d\n" % len(data))
if data:
self._pipeo.write(data)
if flush:
self._pipeo.flush()
self._readerr()
instance = sshpeer