mercurial/sshserver.py

transplant: handle non-empty patches doing nothing (issue2806)

If patch.patch() reports patched files when applying a changeset and the
following commit says nothing changed, transplant used to abort with a
RuntimeError, assuming something went wrong with patching.

The mismatch is patch.patch() reports patched files, not changed ones.
It could be modified to report changed files but it means duplicating
work from status, may be expensive in the case of binary files, and is
probably not that useful at API level. For instance, if two patches are
applied on the working directory, the outcome may be nothing changed
while each call would have returned modified files. The caller would
have to call status() itself again.

This patch fixes the issue by trusting patching code: if the patch
succeeded and commit reports nothing changed, then nothing changed,
patch() did not "dropped changes on the floor".

# 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 = ui.fin
        self.fout = ui.fout

        hook.redirect(True)
        ui.fout = repo.ui.fout = ui.ferr

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

    def getargs(self, args):
        data = {}
        keys = args.split()
        for n in xrange(len(keys)):
            argline = self.fin.readline()[:-1]
            arg, l = argline.split()
            if arg not in keys:
                raise util.Abort("unexpected parameter %r" % arg)
            if arg == '*':
                star = {}
                for k in xrange(int(l)):
                    argline = self.fin.readline()[:-1]
                    arg, l = argline.split()
                    val = self.fin.read(int(l))
                    star[arg] = val
                data['*'] = star
            else:
                val = self.fin.read(int(l))
                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 sendooberror(self, rsp):
        self.ui.ferr.write('%s\n-\n' % rsp.message)
        self.ui.ferr.flush()
        self.fout.write('\n')
        self.fout.flush()

    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,
        wireproto.ooberror: sendooberror,
    }

    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())
        self.lock.release()
        return str(r)

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