view mercurial/sshserver.py @ 7180:a42d27bc809d

hgweb: be sure to drain request data even in early error conditions

Thanks to Mads Kiilerich with noticing this. The hg client can only read data
after all the sent data has been read, so we have to read all the request data
even if we're not going to do anything with it (in error conditions). This
is not easy to fix in the client, because we're using Python's httplib, which
is strictly stateful. Abstracted the draining into a separate method.

# 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, incorporated herein by reference.

from i18n import _
from node import bin, hex
import os, streamclone, sys, tempfile, util, hook

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 getarg(self):
        argline = self.fin.readline()[:-1]
        arg, l = argline.split()
        val = self.fin.read(int(l))
        return arg, val

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

    def serve_forever(self):
        while self.serve_one(): pass
        sys.exit(0)

    def serve_one(self):
        cmd = self.fin.readline()[:-1]
        if cmd:
            impl = getattr(self, 'do_' + cmd, None)
            if impl: impl()
            else: self.respond("")
        return cmd != ''

    def do_lookup(self):
        arg, key = self.getarg()
        assert arg == 'key'
        try:
            r = hex(self.repo.lookup(key))
            success = 1
        except Exception,inst:
            r = str(inst)
            success = 0
        self.respond("%s %s\n" % (success, r))

    def do_heads(self):
        h = self.repo.heads()
        self.respond(" ".join(map(hex, h)) + "\n")

    def do_hello(self):
        '''the hello command returns a set of lines describing various
        interesting things about the server, in an RFC822-like format.
        Currently the only one defined is "capabilities", which
        consists of a line in the form:

        capabilities: space separated list of tokens
        '''

        caps = ['unbundle', 'lookup', 'changegroupsubset']
        if self.ui.configbool('server', 'uncompressed'):
            caps.append('stream=%d' % self.repo.changelog.version)
        self.respond("capabilities: %s\n" % (' '.join(caps),))

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

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

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

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

    def do_branches(self):
        arg, nodes = self.getarg()
        nodes = map(bin, nodes.split(" "))
        r = []
        for b in self.repo.branches(nodes):
            r.append(" ".join(map(hex, b)) + "\n")
        self.respond("".join(r))

    def do_between(self):
        arg, pairs = self.getarg()
        pairs = [map(bin, p.split("-")) for p in pairs.split(" ")]
        r = []
        for b in self.repo.between(pairs):
            r.append(" ".join(map(hex, b)) + "\n")
        self.respond("".join(r))

    def do_changegroup(self):
        nodes = []
        arg, roots = self.getarg()
        nodes = map(bin, roots.split(" "))

        cg = self.repo.changegroup(nodes, 'serve')
        while True:
            d = cg.read(4096)
            if not d:
                break
            self.fout.write(d)

        self.fout.flush()

    def do_changegroupsubset(self):
        bases = []
        heads = []
        argmap = dict([self.getarg(), self.getarg()])
        bases = [bin(n) for n in argmap['bases'].split(' ')]
        heads = [bin(n) for n in argmap['heads'].split(' ')]

        cg = self.repo.changegroupsubset(bases, heads, 'serve')
        while True:
            d = cg.read(4096)
            if not d:
                break
            self.fout.write(d)

        self.fout.flush()

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

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

        self.respond("")
        r = self.repo.addchangegroup(self.fin, 'serve', self.client_url())
        self.respond(str(r))

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

    def do_unbundle(self):
        their_heads = self.getarg()[1].split()

        def check_heads():
            heads = map(hex, self.repo.heads())
            return their_heads == [hex('force')] or their_heads == heads

        # fail early if possible
        if not check_heads():
            self.respond(_('unsynced changes'))
            return

        self.respond('')

        # write bundle data to temporary file because it can be big
        tempname = fp = None
        try:
            fd, tempname = tempfile.mkstemp(prefix='hg-unbundle-')
            fp = os.fdopen(fd, 'wb+')

            count = int(self.fin.readline())
            while count:
                fp.write(self.fin.read(count))
                count = int(self.fin.readline())

            was_locked = self.lock is not None
            if not was_locked:
                self.lock = self.repo.lock()
            try:
                if not check_heads():
                    # someone else committed/pushed/unbundled while we
                    # were transferring data
                    self.respond(_('unsynced changes'))
                    return
                self.respond('')

                # push can proceed

                fp.seek(0)
                r = self.repo.addchangegroup(fp, 'serve', self.client_url())
                self.respond(str(r))
            finally:
                if not was_locked:
                    self.lock.release()
                    self.lock = None
        finally:
            if fp is not None:
                fp.close()
            if tempname is not None:
                os.unlink(tempname)

    def do_stream_out(self):
        try:
            for chunk in streamclone.stream_out(self.repo):
                self.fout.write(chunk)
            self.fout.flush()
        except streamclone.StreamException, inst:
            self.fout.write(str(inst))
            self.fout.flush()