mercurial/sshrepo.py

localrepo.commit: normalize commit message even for rawcommit.

This normalization consists of:
- stripping trailing whitespace
- always using "\n" as the line separator

I think the main reason rawcommit was skipping this normalization was
an attempt to preserve hashes during an hg->hg conversion.

While this is a nice goal, it's not particularly interesting in
practice.  Since SHA-1 is so strong, the only safe way to do it is to
have absolutely identical revisions.  But:

- if the original revision was created with a recent version of hg,
  the commit message will be the same, with or without that
  normalization

- if it was created with an ancient version of hg that didn't do any
  normalization, even if the commit message is identical, the file list
  in the changelog is likely to be different (e.g. no removed files),
  and there were some old issues with e.g. extra file merging, which
  will end up changing the hash anyway

- in any case, if one *really* has to preserve hashes, it's easier
  (and faster) to fake a partial conversion using something like:

  hg clone -U -r rev orig-repo new-repo
  hg -R new-repo log --template '#node# #node#\n' > new-repo/.hg/shamap

Additionally, we've had some reports of problems arising from this lack
of normalization - e.g. issue871, and a user that was wondering why
hg export/hg import was not preserving hashes when there was nothing
unusual going on (it was just import doing the normalization that had
been skipped).

This also means that it's even more unlikely to get identical revisions
when going $VCS->hg->$VCS.

# 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, incorporated herein by reference.

from node import bin, hex
from remoterepo import remotelock, remoterepository
from i18n import _
import repo, os, re, util

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

        m = re.match(r'^ssh://(([^@]+)@)?([^:/]+)(:(\d+))?(/(.*))?$', path)
        if not m:
            self.raise_(repo.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.raise_(repo.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 = os.popen3(cmd, 'b')

        # skip any noise generated by remote shell
        self.do_cmd("hello")
        r = self.do_cmd("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.raise_(repo.RepoError(_("no suitable response from remote hg")))

        self.capabilities = util.set()
        lines.reverse()
        for l in 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 raise_(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 do_cmd(self, cmd, **args):
        self.ui.debug(_("sending %s command\n") % cmd)
        self.pipeo.write("%s\n" % cmd)
        for k, v in args.items():
            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.do_cmd(cmd, **args)
        return self._recv()

    def _recv(self):
        l = self.pipei.readline()
        self.readerr()
        try:
            l = int(l)
        except:
            self.raise_(util.UnexpectedOutput(_("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 lookup(self, key):
        self.requirecap('lookup', _('look up remote revision'))
        d = self.call("lookup", key=key)
        success, data = d[:-1].split(" ", 1)
        if int(success):
            return bin(data)
        else:
            self.raise_(repo.RepoError(data))

    def heads(self):
        d = self.call("heads")
        try:
            return map(bin, d[:-1].split(" "))
        except:
            self.raise_(util.UnexpectedOutput(_("unexpected response:"), d))

    def branches(self, nodes):
        n = " ".join(map(hex, nodes))
        d = self.call("branches", nodes=n)
        try:
            br = [ tuple(map(bin, b.split(" "))) for b in d.splitlines() ]
            return br
        except:
            self.raise_(util.UnexpectedOutput(_("unexpected response:"), d))

    def between(self, pairs):
        n = "\n".join(["-".join(map(hex, p)) for p in pairs])
        d = self.call("between", pairs=n)
        try:
            p = [ l and map(bin, l.split(" ")) or [] for l in d.splitlines() ]
            return p
        except:
            self.raise_(util.UnexpectedOutput(_("unexpected response:"), d))

    def changegroup(self, nodes, kind):
        n = " ".join(map(hex, nodes))
        return self.do_cmd("changegroup", roots=n)

    def changegroupsubset(self, bases, heads, kind):
        self.requirecap('changegroupsubset', _('look up remote changes'))
        bases = " ".join(map(hex, bases))
        heads = " ".join(map(hex, heads))
        return self.do_cmd("changegroupsubset", bases=bases, heads=heads)

    def unbundle(self, cg, heads, source):
        d = self.call("unbundle", heads=' '.join(map(hex, heads)))
        if d:
            # remote may send "unsynced changes"
            self.raise_(repo.RepoError(_("push refused: %s") % d))

        while 1:
            d = cg.read(4096)
            if not d:
                break
            self._send(d)

        self._send("", flush=True)

        r = self._recv()
        if r:
            # remote may send "unsynced changes"
            self.raise_(repo.RepoError(_("push failed: %s") % r))

        r = self._recv()
        try:
            return int(r)
        except:
            self.raise_(util.UnexpectedOutput(_("unexpected response:"), r))

    def addchangegroup(self, cg, source, url):
        d = self.call("addchangegroup")
        if d:
            self.raise_(repo.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.raise_(util.UnexpectedOutput(_("unexpected response:"), r))

    def stream_out(self):
        return self.do_cmd('stream_out')

instance = sshrepository