mercurial/sshserver.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.

# sshserver.py - ssh protocol server support for mercurial
#
# Copyright 2005-2007 Matt Mackall <[e-mail]>
# 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, hook, wireproto, changegroup
import os, sys

class sshserver(object):
    def __init__(self, ui, repo):
        self.ui = ui
        self.repo = repo
        self.lock = None
        self.fin = sys.stdin
        self.fout = sys.stdout

        hook.redirect(True)
        sys.stdout = sys.stderr

        # Prevent insertion/deletion of CRs
        util.set_binary(self.fin)
        util.set_binary(self.fout)

    def getargs(self, args):
        data = {}
        keys = args.split()
        count = len(keys)
        for n in xrange(len(keys)):
            argline = self.fin.readline()[:-1]
            arg, l = argline.split()
            val = self.fin.read(int(l))
            if arg not in keys:
                raise util.Abort("unexpected parameter %r" % arg)
            if arg == '*':
                star = {}
                for n in xrange(int(l)):
                    arg, l = argline.split()
                    val = self.fin.read(int(l))
                    star[arg] = val
                data['*'] = star
            else:
                data[arg] = val
        return [data[k] for k in keys]

    def getarg(self, name):
        return self.getargs(name)[0]

    def getfile(self, fpout):
        self.sendresponse('')
        count = int(self.fin.readline())
        while count:
            fpout.write(self.fin.read(count))
            count = int(self.fin.readline())

    def redirect(self):
        pass

    def groupchunks(self, changegroup):
        while True:
            d = changegroup.read(4096)
            if not d:
                break
            yield d

    def sendresponse(self, v):
        self.fout.write("%d\n" % len(v))
        self.fout.write(v)
        self.fout.flush()

    def sendstream(self, source):
        for chunk in source.gen:
            self.fout.write(chunk)
        self.fout.flush()

    def sendpushresponse(self, rsp):
        self.sendresponse('')
        self.sendresponse(str(rsp.res))

    def sendpusherror(self, rsp):
        self.sendresponse(rsp.res)

    def serve_forever(self):
        try:
            while self.serve_one():
                pass
        finally:
            if self.lock is not None:
                self.lock.release()
        sys.exit(0)

    handlers = {
        str: sendresponse,
        wireproto.streamres: sendstream,
        wireproto.pushres: sendpushresponse,
        wireproto.pusherr: sendpusherror,
    }

    def serve_one(self):
        cmd = self.fin.readline()[:-1]
        if cmd and cmd in wireproto.commands:
            rsp = wireproto.dispatch(self.repo, self, cmd)
            self.handlers[rsp.__class__](self, rsp)
        elif cmd:
            impl = getattr(self, 'do_' + cmd, None)
            if impl:
                r = impl()
                if r is not None:
                    self.sendresponse(r)
            else: self.sendresponse("")
        return cmd != ''

    def do_lock(self):
        '''DEPRECATED - allowing remote client to lock repo is not safe'''

        self.lock = self.repo.lock()
        return ""

    def do_unlock(self):
        '''DEPRECATED'''

        if self.lock:
            self.lock.release()
        self.lock = None
        return ""

    def do_addchangegroup(self):
        '''DEPRECATED'''

        if not self.lock:
            self.sendresponse("not locked")
            return

        self.sendresponse("")
        cg = changegroup.unbundle10(self.fin, "UN")
        r = self.repo.addchangegroup(cg, 'serve', self._client(),
                                     lock=self.lock)
        return str(r)

    def _client(self):
        client = os.environ.get('SSH_CLIENT', '').split(' ', 1)[0]
        return 'remote:ssh:' + client