mercurial/sshrepo.py

checknlink: return False if .hgtmp file preexists (issue2517)

If os_link fails on Windows, errno is always errno.EINVAL,
so we can't really say if the testlink could not be created
because (a) the FS doesn't support hardlinks or (b) there
is a leaked .hgtmp file lying around from a previous crashed
run.

So let's err on the safe side, keep the code simple and assume
we can't detect hardlinks in both cases.

# sshrepo.py - ssh repository proxy class for mercurial
#
# Copyright 2005, 2006 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 i18n import _
import util, error, wireproto
import re

class remotelock(object):
    def __init__(self, repo):
        self.repo = repo
    def release(self):
        self.repo.unlock()
        self.repo = None
    def __del__(self):
        if self.repo:
            self.release()

class sshrepository(wireproto.wirerepository):
    def __init__(self, ui, path, create=0):
        self._url = path
        self.ui = ui

        m = re.match(r'^ssh://(([^@]+)@)?([^:/]+)(:(\d+))?(/(.*))?$', path)
        if not m:
            self._abort(error.RepoError(_("couldn't parse location %s") % path))

        self.user = m.group(2)
        self.host = m.group(3)
        self.port = m.group(5)
        self.path = m.group(7) or "."

        sshcmd = self.ui.config("ui", "ssh", "ssh")
        remotecmd = self.ui.config("ui", "remotecmd", "hg")

        args = util.sshargs(sshcmd, self.host, self.user, self.port)

        if create:
            cmd = '%s %s "%s init %s"'
            cmd = cmd % (sshcmd, args, remotecmd, self.path)

            ui.note(_('running %s\n') % cmd)
            res = util.system(cmd)
            if res != 0:
                self._abort(error.RepoError(_("could not create remote repo")))

        self.validate_repo(ui, sshcmd, args, remotecmd)

    def url(self):
        return self._url

    def validate_repo(self, ui, sshcmd, args, remotecmd):
        # cleanup up previous run
        self.cleanup()

        cmd = '%s %s "%s -R %s serve --stdio"'
        cmd = cmd % (sshcmd, args, remotecmd, self.path)

        cmd = util.quotecommand(cmd)
        ui.note(_('running %s\n') % cmd)
        self.pipeo, self.pipei, self.pipee = util.popen3(cmd)

        # skip any noise generated by remote shell
        self._callstream("hello")
        r = self._callstream("between", pairs=("%s-%s" % ("0"*40, "0"*40)))
        lines = ["", "dummy"]
        max_noise = 500
        while lines[-1] and max_noise:
            l = r.readline()
            self.readerr()
            if lines[-1] == "1\n" and l == "\n":
                break
            if l:
                ui.debug("remote: ", l)
            lines.append(l)
            max_noise -= 1
        else:
            self._abort(error.RepoError(_("no suitable response from remote hg")))

        self.capabilities = set()
        for l in reversed(lines):
            if l.startswith("capabilities:"):
                self.capabilities.update(l[:-1].split(":")[1].split())
                break

    def readerr(self):
        while 1:
            size = util.fstat(self.pipee).st_size
            if size == 0:
                break
            l = self.pipee.readline()
            if not l:
                break
            self.ui.status(_("remote: "), l)

    def _abort(self, exception):
        self.cleanup()
        raise exception

    def cleanup(self):
        try:
            self.pipeo.close()
            self.pipei.close()
            # read the error descriptor until EOF
            for l in self.pipee:
                self.ui.status(_("remote: "), l)
            self.pipee.close()
        except:
            pass

    __del__ = cleanup

    def _callstream(self, cmd, **args):
        self.ui.debug("sending %s command\n" % cmd)
        self.pipeo.write("%s\n" % cmd)
        for k, v in sorted(args.iteritems()):
            self.pipeo.write("%s %d\n" % (k, len(v)))
            self.pipeo.write(v)
        self.pipeo.flush()

        return self.pipei

    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
        while 1:
            d = fp.read(4096)
            if not d:
                break
            self._send(d)
        self._send("", flush=True)
        r = self._recv()
        if r:
            return '', r
        return self._recv(), ''

    def _decompress(self, stream):
        return stream

    def _recv(self):
        l = self.pipei.readline()
        self.readerr()
        try:
            l = int(l)
        except:
            self._abort(error.ResponseError(_("unexpected response:"), l))
        return self.pipei.read(l)

    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()

    def lock(self):
        self._call("lock")
        return remotelock(self)

    def unlock(self):
        self._call("unlock")

    def addchangegroup(self, cg, source, url):
        '''Send a changegroup to the remote server.  Return an integer
        similar to unbundle(). DEPRECATED, since it requires locking the
        remote.'''
        d = self._call("addchangegroup")
        if d:
            self._abort(error.RepoError(_("push refused: %s") % d))
        while 1:
            d = cg.read(4096)
            if not d:
                break
            self.pipeo.write(d)
            self.readerr()

        self.pipeo.flush()

        self.readerr()
        r = self._recv()
        if not r:
            return 1
        try:
            return int(r)
        except:
            self._abort(error.ResponseError(_("unexpected response:"), r))

instance = sshrepository