stream-clone: factor computation of requirement of a stream clone

This gather code duplicated in multiple place and will make it easier to modify
it safely in the future.

Differential Revision: https://phab.mercurial-scm.org/D12028

mercurial/streamclone.py

@@ -1,932 +1,941 b''
 # streamclone.py - producing and consuming streaming repository data
 #
 # Copyright 2015 Gregory Szorc <[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 __future__ import absolute_import
 
 import contextlib
 import errno
 import os
 import struct
 
 from .i18n import _
 from .pycompat import open
 from .interfaces import repository
 from . import (
     bookmarks,
     cacheutil,
     error,
     narrowspec,
     phases,
     pycompat,
     requirements as requirementsmod,
     scmutil,
     store,
     util,
 )
 from .utils import (
     stringutil,
 )
 
 
 def new_stream_clone_requirements(
     supported_formats, default_requirements, streamed_requirements
 ):
     """determine the final set of requirement for a new stream clone
 
     this method combine the "default" requirements that a new repository would
     use with the constaint we get from the stream clone content. We keep local
     configuration choice when possible.
     """
     requirements = set(default_requirements)
     requirements -= supported_formats
     requirements.update(streamed_requirements)
     return requirements
 
 
+def streamed_requirements(repo):
+    """the set of requirement the new clone will have to support
+
+    This is used for advertising the stream options and to generate the actual
+    stream content."""
+    requiredformats = repo.requirements & repo.supportedformats
+    return requiredformats
+
+
 def canperformstreamclone(pullop, bundle2=False):
     """Whether it is possible to perform a streaming clone as part of pull.
 
     ``bundle2`` will cause the function to consider stream clone through
     bundle2 and only through bundle2.
 
     Returns a tuple of (supported, requirements). ``supported`` is True if
     streaming clone is supported and False otherwise. ``requirements`` is
     a set of repo requirements from the remote, or ``None`` if stream clone
     isn't supported.
     """
     repo = pullop.repo
     remote = pullop.remote
 
     bundle2supported = False
     if pullop.canusebundle2:
         if b'v2' in pullop.remotebundle2caps.get(b'stream', []):
             bundle2supported = True
         # else
         # Server doesn't support bundle2 stream clone or doesn't support
         # the versions we support. Fall back and possibly allow legacy.
 
     # Ensures legacy code path uses available bundle2.
     if bundle2supported and not bundle2:
         return False, None
     # Ensures bundle2 doesn't try to do a stream clone if it isn't supported.
     elif bundle2 and not bundle2supported:
         return False, None
 
     # Streaming clone only works on empty repositories.
     if len(repo):
         return False, None
 
     # Streaming clone only works if all data is being requested.
     if pullop.heads:
         return False, None
 
     streamrequested = pullop.streamclonerequested
 
     # If we don't have a preference, let the server decide for us. This
     # likely only comes into play in LANs.
     if streamrequested is None:
         # The server can advertise whether to prefer streaming clone.
         streamrequested = remote.capable(b'stream-preferred')
 
     if not streamrequested:
         return False, None
 
     # In order for stream clone to work, the client has to support all the
     # requirements advertised by the server.
     #
     # The server advertises its requirements via the "stream" and "streamreqs"
     # capability. "stream" (a value-less capability) is advertised if and only
     # if the only requirement is "revlogv1." Else, the "streamreqs" capability
     # is advertised and contains a comma-delimited list of requirements.
     requirements = set()
     if remote.capable(b'stream'):
         requirements.add(requirementsmod.REVLOGV1_REQUIREMENT)
     else:
         streamreqs = remote.capable(b'streamreqs')
         # This is weird and shouldn't happen with modern servers.
         if not streamreqs:
             pullop.repo.ui.warn(
                 _(
                     b'warning: stream clone requested but server has them '
                     b'disabled\n'
                 )
             )
             return False, None
 
         streamreqs = set(streamreqs.split(b','))
         # Server requires something we don't support. Bail.
         missingreqs = streamreqs - repo.supportedformats
         if missingreqs:
             pullop.repo.ui.warn(
                 _(
                     b'warning: stream clone requested but client is missing '
                     b'requirements: %s\n'
                 )
                 % b', '.join(sorted(missingreqs))
             )
             pullop.repo.ui.warn(
                 _(
                     b'(see https://www.mercurial-scm.org/wiki/MissingRequirement '
                     b'for more information)\n'
                 )
             )
             return False, None
         requirements = streamreqs
 
     return True, requirements
 
 
 def maybeperformlegacystreamclone(pullop):
     """Possibly perform a legacy stream clone operation.
 
     Legacy stream clones are performed as part of pull but before all other
     operations.
 
     A legacy stream clone will not be performed if a bundle2 stream clone is
     supported.
     """
     from . import localrepo
 
     supported, requirements = canperformstreamclone(pullop)
 
     if not supported:
         return
 
     repo = pullop.repo
     remote = pullop.remote
 
     # Save remote branchmap. We will use it later to speed up branchcache
     # creation.
     rbranchmap = None
     if remote.capable(b'branchmap'):
         with remote.commandexecutor() as e:
             rbranchmap = e.callcommand(b'branchmap', {}).result()
 
     repo.ui.status(_(b'streaming all changes\n'))
 
     with remote.commandexecutor() as e:
         fp = e.callcommand(b'stream_out', {}).result()
 
     # TODO strictly speaking, this code should all be inside the context
     # manager because the context manager is supposed to ensure all wire state
     # is flushed when exiting. But the legacy peers don't do this, so it
     # doesn't matter.
     l = fp.readline()
     try:
         resp = int(l)
     except ValueError:
         raise error.ResponseError(
             _(b'unexpected response from remote server:'), l
         )
     if resp == 1:
         raise error.Abort(_(b'operation forbidden by server'))
     elif resp == 2:
         raise error.Abort(_(b'locking the remote repository failed'))
     elif resp != 0:
         raise error.Abort(_(b'the server sent an unknown error code'))
 
     l = fp.readline()
     try:
         filecount, bytecount = map(int, l.split(b' ', 1))
     except (ValueError, TypeError):
         raise error.ResponseError(
             _(b'unexpected response from remote server:'), l
         )
 
     with repo.lock():
         consumev1(repo, fp, filecount, bytecount)
         repo.requirements = new_stream_clone_requirements(
             repo.supportedformats,
             repo.requirements,
             requirements,
         )
         repo.svfs.options = localrepo.resolvestorevfsoptions(
             repo.ui, repo.requirements, repo.features
         )
         scmutil.writereporequirements(repo)
 
         if rbranchmap:
             repo._branchcaches.replace(repo, rbranchmap)
 
         repo.invalidate()
 
 
 def allowservergeneration(repo):
     """Whether streaming clones are allowed from the server."""
     if repository.REPO_FEATURE_STREAM_CLONE not in repo.features:
         return False
 
     if not repo.ui.configbool(b'server', b'uncompressed', untrusted=True):
         return False
 
     # The way stream clone works makes it impossible to hide secret changesets.
     # So don't allow this by default.
     secret = phases.hassecret(repo)
     if secret:
         return repo.ui.configbool(b'server', b'uncompressedallowsecret')
 
     return True
 
 
 # This is it's own function so extensions can override it.
 def _walkstreamfiles(repo, matcher=None):
     return repo.store.walk(matcher)
 
 
 def generatev1(repo):
     """Emit content for version 1 of a streaming clone.
 
     This returns a 3-tuple of (file count, byte size, data iterator).
 
     The data iterator consists of N entries for each file being transferred.
     Each file entry starts as a line with the file name and integer size
     delimited by a null byte.
 
     The raw file data follows. Following the raw file data is the next file
     entry, or EOF.
 
     When used on the wire protocol, an additional line indicating protocol
     success will be prepended to the stream. This function is not responsible
     for adding it.
 
     This function will obtain a repository lock to ensure a consistent view of
     the store is captured. It therefore may raise LockError.
     """
     entries = []
     total_bytes = 0
     # Get consistent snapshot of repo, lock during scan.
     with repo.lock():
         repo.ui.debug(b'scanning\n')
         for file_type, name, size in _walkstreamfiles(repo):
             if size:
                 entries.append((name, size))
                 total_bytes += size
         _test_sync_point_walk_1(repo)
     _test_sync_point_walk_2(repo)
 
     repo.ui.debug(
         b'%d files, %d bytes to transfer\n' % (len(entries), total_bytes)
     )
 
     svfs = repo.svfs
     debugflag = repo.ui.debugflag
 
     def emitrevlogdata():
         for name, size in entries:
             if debugflag:
                 repo.ui.debug(b'sending %s (%d bytes)\n' % (name, size))
             # partially encode name over the wire for backwards compat
             yield b'%s\0%d\n' % (store.encodedir(name), size)
             # auditing at this stage is both pointless (paths are already
             # trusted by the local repo) and expensive
             with svfs(name, b'rb', auditpath=False) as fp:
                 if size <= 65536:
                     yield fp.read(size)
                 else:
                     for chunk in util.filechunkiter(fp, limit=size):
                         yield chunk
 
     return len(entries), total_bytes, emitrevlogdata()
 
 
 def generatev1wireproto(repo):
     """Emit content for version 1 of streaming clone suitable for the wire.
 
     This is the data output from ``generatev1()`` with 2 header lines. The
     first line indicates overall success. The 2nd contains the file count and
     byte size of payload.
 
     The success line contains "0" for success, "1" for stream generation not
     allowed, and "2" for error locking the repository (possibly indicating
     a permissions error for the server process).
     """
     if not allowservergeneration(repo):
         yield b'1\n'
         return
 
     try:
         filecount, bytecount, it = generatev1(repo)
     except error.LockError:
         yield b'2\n'
         return
 
     # Indicates successful response.
     yield b'0\n'
     yield b'%d %d\n' % (filecount, bytecount)
     for chunk in it:
         yield chunk
 
 
 def generatebundlev1(repo, compression=b'UN'):
     """Emit content for version 1 of a stream clone bundle.
 
     The first 4 bytes of the output ("HGS1") denote this as stream clone
     bundle version 1.
 
     The next 2 bytes indicate the compression type. Only "UN" is currently
     supported.
 
     The next 16 bytes are two 64-bit big endian unsigned integers indicating
     file count and byte count, respectively.
 
     The next 2 bytes is a 16-bit big endian unsigned short declaring the length
     of the requirements string, including a trailing \0. The following N bytes
     are the requirements string, which is ASCII containing a comma-delimited
     list of repo requirements that are needed to support the data.
 
     The remaining content is the output of ``generatev1()`` (which may be
     compressed in the future).
 
     Returns a tuple of (requirements, data generator).
     """
     if compression != b'UN':
         raise ValueError(b'we do not support the compression argument yet')
 
-    requirements = repo.requirements & repo.supportedformats
+    requirements = streamed_requirements(repo)
     requires = b','.join(sorted(requirements))
 
     def gen():
         yield b'HGS1'
         yield compression
 
         filecount, bytecount, it = generatev1(repo)
         repo.ui.status(
             _(b'writing %d bytes for %d files\n') % (bytecount, filecount)
         )
 
         yield struct.pack(b'>QQ', filecount, bytecount)
         yield struct.pack(b'>H', len(requires) + 1)
         yield requires + b'\0'
 
         # This is where we'll add compression in the future.
         assert compression == b'UN'
 
         progress = repo.ui.makeprogress(
             _(b'bundle'), total=bytecount, unit=_(b'bytes')
         )
         progress.update(0)
 
         for chunk in it:
             progress.increment(step=len(chunk))
             yield chunk
 
         progress.complete()
 
     return requirements, gen()
 
 
 def consumev1(repo, fp, filecount, bytecount):
     """Apply the contents from version 1 of a streaming clone file handle.
 
     This takes the output from "stream_out" and applies it to the specified
     repository.
 
     Like "stream_out," the status line added by the wire protocol is not
     handled by this function.
     """
     with repo.lock():
         repo.ui.status(
             _(b'%d files to transfer, %s of data\n')
             % (filecount, util.bytecount(bytecount))
         )
         progress = repo.ui.makeprogress(
             _(b'clone'), total=bytecount, unit=_(b'bytes')
         )
         progress.update(0)
         start = util.timer()
 
         # TODO: get rid of (potential) inconsistency
         #
         # If transaction is started and any @filecache property is
         # changed at this point, it causes inconsistency between
         # in-memory cached property and streamclone-ed file on the
         # disk. Nested transaction prevents transaction scope "clone"
         # below from writing in-memory changes out at the end of it,
         # even though in-memory changes are discarded at the end of it
         # regardless of transaction nesting.
         #
         # But transaction nesting can't be simply prohibited, because
         # nesting occurs also in ordinary case (e.g. enabling
         # clonebundles).
 
         with repo.transaction(b'clone'):
             with repo.svfs.backgroundclosing(repo.ui, expectedcount=filecount):
                 for i in pycompat.xrange(filecount):
                     # XXX doesn't support '\n' or '\r' in filenames
                     l = fp.readline()
                     try:
                         name, size = l.split(b'\0', 1)
                         size = int(size)
                     except (ValueError, TypeError):
                         raise error.ResponseError(
                             _(b'unexpected response from remote server:'), l
                         )
                     if repo.ui.debugflag:
                         repo.ui.debug(
                             b'adding %s (%s)\n' % (name, util.bytecount(size))
                         )
                     # for backwards compat, name was partially encoded
                     path = store.decodedir(name)
                     with repo.svfs(path, b'w', backgroundclose=True) as ofp:
                         for chunk in util.filechunkiter(fp, limit=size):
                             progress.increment(step=len(chunk))
                             ofp.write(chunk)
 
             # force @filecache properties to be reloaded from
             # streamclone-ed file at next access
             repo.invalidate(clearfilecache=True)
 
         elapsed = util.timer() - start
         if elapsed <= 0:
             elapsed = 0.001
         progress.complete()
         repo.ui.status(
             _(b'transferred %s in %.1f seconds (%s/sec)\n')
             % (
                 util.bytecount(bytecount),
                 elapsed,
                 util.bytecount(bytecount / elapsed),
             )
         )
 
 
 def readbundle1header(fp):
     compression = fp.read(2)
     if compression != b'UN':
         raise error.Abort(
             _(
                 b'only uncompressed stream clone bundles are '
                 b'supported; got %s'
             )
             % compression
         )
 
     filecount, bytecount = struct.unpack(b'>QQ', fp.read(16))
     requireslen = struct.unpack(b'>H', fp.read(2))[0]
     requires = fp.read(requireslen)
 
     if not requires.endswith(b'\0'):
         raise error.Abort(
             _(
                 b'malformed stream clone bundle: '
                 b'requirements not properly encoded'
             )
         )
 
     requirements = set(requires.rstrip(b'\0').split(b','))
 
     return filecount, bytecount, requirements
 
 
 def applybundlev1(repo, fp):
     """Apply the content from a stream clone bundle version 1.
 
     We assume the 4 byte header has been read and validated and the file handle
     is at the 2 byte compression identifier.
     """
     if len(repo):
         raise error.Abort(
             _(b'cannot apply stream clone bundle on non-empty repo')
         )
 
     filecount, bytecount, requirements = readbundle1header(fp)
     missingreqs = requirements - repo.supportedformats
     if missingreqs:
         raise error.Abort(
             _(b'unable to apply stream clone: unsupported format: %s')
             % b', '.join(sorted(missingreqs))
         )
 
     consumev1(repo, fp, filecount, bytecount)
 
 
 class streamcloneapplier(object):
     """Class to manage applying streaming clone bundles.
 
     We need to wrap ``applybundlev1()`` in a dedicated type to enable bundle
     readers to perform bundle type-specific functionality.
     """
 
     def __init__(self, fh):
         self._fh = fh
 
     def apply(self, repo):
         return applybundlev1(repo, self._fh)
 
 
 # type of file to stream
 _fileappend = 0  # append only file
 _filefull = 1  # full snapshot file
 
 # Source of the file
 _srcstore = b's'  # store (svfs)
 _srccache = b'c'  # cache (cache)
 
 # This is it's own function so extensions can override it.
 def _walkstreamfullstorefiles(repo):
     """list snapshot file from the store"""
     fnames = []
     if not repo.publishing():
         fnames.append(b'phaseroots')
     return fnames
 
 
 def _filterfull(entry, copy, vfsmap):
     """actually copy the snapshot files"""
     src, name, ftype, data = entry
     if ftype != _filefull:
         return entry
     return (src, name, ftype, copy(vfsmap[src].join(name)))
 
 
 @contextlib.contextmanager
 def maketempcopies():
     """return a function to temporary copy file"""
     files = []
     try:
 
         def copy(src):
             fd, dst = pycompat.mkstemp()
             os.close(fd)
             files.append(dst)
             util.copyfiles(src, dst, hardlink=True)
             return dst
 
         yield copy
     finally:
         for tmp in files:
             util.tryunlink(tmp)
 
 
 def _makemap(repo):
     """make a (src -> vfs) map for the repo"""
     vfsmap = {
         _srcstore: repo.svfs,
         _srccache: repo.cachevfs,
     }
     # we keep repo.vfs out of the on purpose, ther are too many danger there
     # (eg: .hg/hgrc)
     assert repo.vfs not in vfsmap.values()
 
     return vfsmap
 
 
 def _emit2(repo, entries, totalfilesize):
     """actually emit the stream bundle"""
     vfsmap = _makemap(repo)
     # we keep repo.vfs out of the on purpose, ther are too many danger there
     # (eg: .hg/hgrc),
     #
     # this assert is duplicated (from _makemap) as author might think this is
     # fine, while this is really not fine.
     if repo.vfs in vfsmap.values():
         raise error.ProgrammingError(
             b'repo.vfs must not be added to vfsmap for security reasons'
         )
 
     progress = repo.ui.makeprogress(
         _(b'bundle'), total=totalfilesize, unit=_(b'bytes')
     )
     progress.update(0)
     with maketempcopies() as copy, progress:
         # copy is delayed until we are in the try
         entries = [_filterfull(e, copy, vfsmap) for e in entries]
         yield None  # this release the lock on the repository
         totalbytecount = 0
 
         for src, name, ftype, data in entries:
             vfs = vfsmap[src]
             yield src
             yield util.uvarintencode(len(name))
             if ftype == _fileappend:
                 fp = vfs(name)
                 size = data
             elif ftype == _filefull:
                 fp = open(data, b'rb')
                 size = util.fstat(fp).st_size
             bytecount = 0
             try:
                 yield util.uvarintencode(size)
                 yield name
                 if size <= 65536:
                     chunks = (fp.read(size),)
                 else:
                     chunks = util.filechunkiter(fp, limit=size)
                 for chunk in chunks:
                     bytecount += len(chunk)
                     totalbytecount += len(chunk)
                     progress.update(totalbytecount)
                     yield chunk
                 if bytecount != size:
                     # Would most likely be caused by a race due to `hg strip` or
                     # a revlog split
                     raise error.Abort(
                         _(
                             b'clone could only read %d bytes from %s, but '
                             b'expected %d bytes'
                         )
                         % (bytecount, name, size)
                     )
             finally:
                 fp.close()
 
 
 def _test_sync_point_walk_1(repo):
     """a function for synchronisation during tests"""
 
 
 def _test_sync_point_walk_2(repo):
     """a function for synchronisation during tests"""
 
 
 def _v2_walk(repo, includes, excludes, includeobsmarkers):
     """emit a seris of files information useful to clone a repo
 
     return (entries, totalfilesize)
 
     entries is a list of tuple (vfs-key, file-path, file-type, size)
 
     - `vfs-key`: is a key to the right vfs to write the file (see _makemap)
     - `name`: file path of the file to copy (to be feed to the vfss)
     - `file-type`: do this file need to be copied with the source lock ?
     - `size`: the size of the file (or None)
     """
     assert repo._currentlock(repo._lockref) is not None
     entries = []
     totalfilesize = 0
 
     matcher = None
     if includes or excludes:
         matcher = narrowspec.match(repo.root, includes, excludes)
 
     for rl_type, name, size in _walkstreamfiles(repo, matcher):
         if size:
             ft = _fileappend
             if rl_type & store.FILEFLAGS_VOLATILE:
                 ft = _filefull
             entries.append((_srcstore, name, ft, size))
             totalfilesize += size
     for name in _walkstreamfullstorefiles(repo):
         if repo.svfs.exists(name):
             totalfilesize += repo.svfs.lstat(name).st_size
             entries.append((_srcstore, name, _filefull, None))
     if includeobsmarkers and repo.svfs.exists(b'obsstore'):
         totalfilesize += repo.svfs.lstat(b'obsstore').st_size
         entries.append((_srcstore, b'obsstore', _filefull, None))
     for name in cacheutil.cachetocopy(repo):
         if repo.cachevfs.exists(name):
             totalfilesize += repo.cachevfs.lstat(name).st_size
             entries.append((_srccache, name, _filefull, None))
     return entries, totalfilesize
 
 
 def generatev2(repo, includes, excludes, includeobsmarkers):
     """Emit content for version 2 of a streaming clone.
 
     the data stream consists the following entries:
     1) A char representing the file destination (eg: store or cache)
     2) A varint containing the length of the filename
     3) A varint containing the length of file data
     4) N bytes containing the filename (the internal, store-agnostic form)
     5) N bytes containing the file data
 
     Returns a 3-tuple of (file count, file size, data iterator).
     """
 
     with repo.lock():
 
         repo.ui.debug(b'scanning\n')
 
         entries, totalfilesize = _v2_walk(
             repo,
             includes=includes,
             excludes=excludes,
             includeobsmarkers=includeobsmarkers,
         )
 
         chunks = _emit2(repo, entries, totalfilesize)
         first = next(chunks)
         assert first is None
         _test_sync_point_walk_1(repo)
     _test_sync_point_walk_2(repo)
 
     return len(entries), totalfilesize, chunks
 
 
 @contextlib.contextmanager
 def nested(*ctxs):
     this = ctxs[0]
     rest = ctxs[1:]
     with this:
         if rest:
             with nested(*rest):
                 yield
         else:
             yield
 
 
 def consumev2(repo, fp, filecount, filesize):
     """Apply the contents from a version 2 streaming clone.
 
     Data is read from an object that only needs to provide a ``read(size)``
     method.
     """
     with repo.lock():
         repo.ui.status(
             _(b'%d files to transfer, %s of data\n')
             % (filecount, util.bytecount(filesize))
         )
 
         start = util.timer()
         progress = repo.ui.makeprogress(
             _(b'clone'), total=filesize, unit=_(b'bytes')
         )
         progress.update(0)
 
         vfsmap = _makemap(repo)
         # we keep repo.vfs out of the on purpose, ther are too many danger
         # there (eg: .hg/hgrc),
         #
         # this assert is duplicated (from _makemap) as author might think this
         # is fine, while this is really not fine.
         if repo.vfs in vfsmap.values():
             raise error.ProgrammingError(
                 b'repo.vfs must not be added to vfsmap for security reasons'
             )
 
         with repo.transaction(b'clone'):
             ctxs = (vfs.backgroundclosing(repo.ui) for vfs in vfsmap.values())
             with nested(*ctxs):
                 for i in range(filecount):
                     src = util.readexactly(fp, 1)
                     vfs = vfsmap[src]
                     namelen = util.uvarintdecodestream(fp)
                     datalen = util.uvarintdecodestream(fp)
 
                     name = util.readexactly(fp, namelen)
 
                     if repo.ui.debugflag:
                         repo.ui.debug(
                             b'adding [%s] %s (%s)\n'
                             % (src, name, util.bytecount(datalen))
                         )
 
                     with vfs(name, b'w') as ofp:
                         for chunk in util.filechunkiter(fp, limit=datalen):
                             progress.increment(step=len(chunk))
                             ofp.write(chunk)
 
             # force @filecache properties to be reloaded from
             # streamclone-ed file at next access
             repo.invalidate(clearfilecache=True)
 
         elapsed = util.timer() - start
         if elapsed <= 0:
             elapsed = 0.001
         repo.ui.status(
             _(b'transferred %s in %.1f seconds (%s/sec)\n')
             % (
                 util.bytecount(progress.pos),
                 elapsed,
                 util.bytecount(progress.pos / elapsed),
             )
         )
         progress.complete()
 
 
 def applybundlev2(repo, fp, filecount, filesize, requirements):
     from . import localrepo
 
     missingreqs = [r for r in requirements if r not in repo.supported]
     if missingreqs:
         raise error.Abort(
             _(b'unable to apply stream clone: unsupported format: %s')
             % b', '.join(sorted(missingreqs))
         )
 
     consumev2(repo, fp, filecount, filesize)
 
     repo.requirements = new_stream_clone_requirements(
         repo.supportedformats,
         repo.requirements,
         requirements,
     )
     repo.svfs.options = localrepo.resolvestorevfsoptions(
         repo.ui, repo.requirements, repo.features
     )
     scmutil.writereporequirements(repo)
 
 
 def _copy_files(src_vfs_map, dst_vfs_map, entries, progress):
     hardlink = [True]
 
     def copy_used():
         hardlink[0] = False
         progress.topic = _(b'copying')
 
     for k, path, size in entries:
         src_vfs = src_vfs_map[k]
         dst_vfs = dst_vfs_map[k]
         src_path = src_vfs.join(path)
         dst_path = dst_vfs.join(path)
         # We cannot use dirname and makedirs of dst_vfs here because the store
         # encoding confuses them. See issue 6581 for details.
         dirname = os.path.dirname(dst_path)
         if not os.path.exists(dirname):
             util.makedirs(dirname)
         dst_vfs.register_file(path)
         # XXX we could use the #nb_bytes argument.
         util.copyfile(
             src_path,
             dst_path,
             hardlink=hardlink[0],
             no_hardlink_cb=copy_used,
             check_fs_hardlink=False,
         )
         progress.increment()
     return hardlink[0]
 
 
 def local_copy(src_repo, dest_repo):
     """copy all content from one local repository to another
 
     This is useful for local clone"""
     src_store_requirements = {
         r
         for r in src_repo.requirements
         if r not in requirementsmod.WORKING_DIR_REQUIREMENTS
     }
     dest_store_requirements = {
         r
         for r in dest_repo.requirements
         if r not in requirementsmod.WORKING_DIR_REQUIREMENTS
     }
     assert src_store_requirements == dest_store_requirements
 
     with dest_repo.lock():
         with src_repo.lock():
 
             # bookmark is not integrated to the streaming as it might use the
             # `repo.vfs` and they are too many sentitive data accessible
             # through `repo.vfs` to expose it to streaming clone.
             src_book_vfs = bookmarks.bookmarksvfs(src_repo)
             srcbookmarks = src_book_vfs.join(b'bookmarks')
             bm_count = 0
             if os.path.exists(srcbookmarks):
                 bm_count = 1
 
             entries, totalfilesize = _v2_walk(
                 src_repo,
                 includes=None,
                 excludes=None,
                 includeobsmarkers=True,
             )
             src_vfs_map = _makemap(src_repo)
             dest_vfs_map = _makemap(dest_repo)
             progress = src_repo.ui.makeprogress(
                 topic=_(b'linking'),
                 total=len(entries) + bm_count,
                 unit=_(b'files'),
             )
             # copy  files
             #
             # We could copy the full file while the source repository is locked
             # and the other one without the lock. However, in the linking case,
             # this would also requires checks that nobody is appending any data
             # to the files while we do the clone, so this is not done yet. We
             # could do this blindly when copying files.
             files = ((k, path, size) for k, path, ftype, size in entries)
             hardlink = _copy_files(src_vfs_map, dest_vfs_map, files, progress)
 
             # copy bookmarks over
             if bm_count:
                 dst_book_vfs = bookmarks.bookmarksvfs(dest_repo)
                 dstbookmarks = dst_book_vfs.join(b'bookmarks')
                 util.copyfile(srcbookmarks, dstbookmarks)
         progress.complete()
         if hardlink:
             msg = b'linked %d files\n'
         else:
             msg = b'copied %d files\n'
         src_repo.ui.debug(msg % (len(entries) + bm_count))
 
         with dest_repo.transaction(b"localclone") as tr:
             dest_repo.store.write(tr)
 
         # clean up transaction file as they do not make sense
         undo_files = [(dest_repo.svfs, b'undo.backupfiles')]
         undo_files.extend(dest_repo.undofiles())
         for undovfs, undofile in undo_files:
             try:
                 undovfs.unlink(undofile)
             except OSError as e:
                 if e.errno != errno.ENOENT:
                     msg = _(b'error removing %s: %s\n')
                     path = undovfs.join(undofile)
                     e_msg = stringutil.forcebytestr(e)
                     msg %= (path, e_msg)
                     dest_repo.ui.warn(msg)

mercurial/wireprotov1server.py

@@ -1,739 +1,739 b''
 # wireprotov1server.py - Wire protocol version 1 server functionality
 #
 # Copyright 2005-2010 Olivia 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 __future__ import absolute_import
 
 import binascii
 import os
 
 from .i18n import _
 from .node import hex
 from .pycompat import getattr
 
 from . import (
     bundle2,
     bundlecaches,
     changegroup as changegroupmod,
     discovery,
     encoding,
     error,
     exchange,
     pushkey as pushkeymod,
     pycompat,
     requirements as requirementsmod,
     streamclone,
     util,
     wireprototypes,
 )
 
 from .utils import (
     procutil,
     stringutil,
 )
 
 urlerr = util.urlerr
 urlreq = util.urlreq
 
 bundle2requiredmain = _(b'incompatible Mercurial client; bundle2 required')
 bundle2requiredhint = _(
     b'see https://www.mercurial-scm.org/wiki/IncompatibleClient'
 )
 bundle2required = b'%s\n(%s)\n' % (bundle2requiredmain, bundle2requiredhint)
 
 
 def clientcompressionsupport(proto):
     """Returns a list of compression methods supported by the client.
 
     Returns a list of the compression methods supported by the client
     according to the protocol capabilities. If no such capability has
     been announced, fallback to the default of zlib and uncompressed.
     """
     for cap in proto.getprotocaps():
         if cap.startswith(b'comp='):
             return cap[5:].split(b',')
     return [b'zlib', b'none']
 
 
 # wire protocol command can either return a string or one of these classes.
 
 
 def getdispatchrepo(repo, proto, command):
     """Obtain the repo used for processing wire protocol commands.
 
     The intent of this function is to serve as a monkeypatch point for
     extensions that need commands to operate on different repo views under
     specialized circumstances.
     """
     viewconfig = repo.ui.config(b'server', b'view')
     return repo.filtered(viewconfig)
 
 
 def dispatch(repo, proto, command):
     repo = getdispatchrepo(repo, proto, command)
 
     func, spec = commands[command]
     args = proto.getargs(spec)
 
     return func(repo, proto, *args)
 
 
 def options(cmd, keys, others):
     opts = {}
     for k in keys:
         if k in others:
             opts[k] = others[k]
             del others[k]
     if others:
         procutil.stderr.write(
             b"warning: %s ignored unexpected arguments %s\n"
             % (cmd, b",".join(others))
         )
     return opts
 
 
 def bundle1allowed(repo, action):
     """Whether a bundle1 operation is allowed from the server.
 
     Priority is:
 
     1. server.bundle1gd.<action> (if generaldelta active)
     2. server.bundle1.<action>
     3. server.bundle1gd (if generaldelta active)
     4. server.bundle1
     """
     ui = repo.ui
     gd = requirementsmod.GENERALDELTA_REQUIREMENT in repo.requirements
 
     if gd:
         v = ui.configbool(b'server', b'bundle1gd.%s' % action)
         if v is not None:
             return v
 
     v = ui.configbool(b'server', b'bundle1.%s' % action)
     if v is not None:
         return v
 
     if gd:
         v = ui.configbool(b'server', b'bundle1gd')
         if v is not None:
             return v
 
     return ui.configbool(b'server', b'bundle1')
 
 
 commands = wireprototypes.commanddict()
 
 
 def wireprotocommand(name, args=None, permission=b'push'):
     """Decorator to declare a wire protocol command.
 
     ``name`` is the name of the wire protocol command being provided.
 
     ``args`` defines the named arguments accepted by the command. It is
     a space-delimited list of argument names. ``*`` denotes a special value
     that says to accept all named arguments.
 
     ``permission`` defines the permission type needed to run this command.
     Can be ``push`` or ``pull``. These roughly map to read-write and read-only,
     respectively. Default is to assume command requires ``push`` permissions
     because otherwise commands not declaring their permissions could modify
     a repository that is supposed to be read-only.
     """
     transports = {
         k for k, v in wireprototypes.TRANSPORTS.items() if v[b'version'] == 1
     }
 
     if permission not in (b'push', b'pull'):
         raise error.ProgrammingError(
             b'invalid wire protocol permission; '
             b'got %s; expected "push" or "pull"' % permission
         )
 
     if args is None:
         args = b''
 
     if not isinstance(args, bytes):
         raise error.ProgrammingError(
             b'arguments for version 1 commands must be declared as bytes'
         )
 
     def register(func):
         if name in commands:
             raise error.ProgrammingError(
                 b'%s command already registered for version 1' % name
             )
         commands[name] = wireprototypes.commandentry(
             func, args=args, transports=transports, permission=permission
         )
 
         return func
 
     return register
 
 
 # TODO define a more appropriate permissions type to use for this.
 @wireprotocommand(b'batch', b'cmds *', permission=b'pull')
 def batch(repo, proto, cmds, others):
     unescapearg = wireprototypes.unescapebatcharg
     res = []
     for pair in cmds.split(b';'):
         op, args = pair.split(b' ', 1)
         vals = {}
         for a in args.split(b','):
             if a:
                 n, v = a.split(b'=')
                 vals[unescapearg(n)] = unescapearg(v)
         func, spec = commands[op]
 
         # Validate that client has permissions to perform this command.
         perm = commands[op].permission
         assert perm in (b'push', b'pull')
         proto.checkperm(perm)
 
         if spec:
             keys = spec.split()
             data = {}
             for k in keys:
                 if k == b'*':
                     star = {}
                     for key in vals.keys():
                         if key not in keys:
                             star[key] = vals[key]
                     data[b'*'] = star
                 else:
                     data[k] = vals[k]
             result = func(repo, proto, *[data[k] for k in keys])
         else:
             result = func(repo, proto)
         if isinstance(result, wireprototypes.ooberror):
             return result
 
         # For now, all batchable commands must return bytesresponse or
         # raw bytes (for backwards compatibility).
         assert isinstance(result, (wireprototypes.bytesresponse, bytes))
         if isinstance(result, wireprototypes.bytesresponse):
             result = result.data
         res.append(wireprototypes.escapebatcharg(result))
 
     return wireprototypes.bytesresponse(b';'.join(res))
 
 
 @wireprotocommand(b'between', b'pairs', permission=b'pull')
 def between(repo, proto, pairs):
     pairs = [wireprototypes.decodelist(p, b'-') for p in pairs.split(b" ")]
     r = []
     for b in repo.between(pairs):
         r.append(wireprototypes.encodelist(b) + b"\n")
 
     return wireprototypes.bytesresponse(b''.join(r))
 
 
 @wireprotocommand(b'branchmap', permission=b'pull')
 def branchmap(repo, proto):
     branchmap = repo.branchmap()
     heads = []
     for branch, nodes in pycompat.iteritems(branchmap):
         branchname = urlreq.quote(encoding.fromlocal(branch))
         branchnodes = wireprototypes.encodelist(nodes)
         heads.append(b'%s %s' % (branchname, branchnodes))
 
     return wireprototypes.bytesresponse(b'\n'.join(heads))
 
 
 @wireprotocommand(b'branches', b'nodes', permission=b'pull')
 def branches(repo, proto, nodes):
     nodes = wireprototypes.decodelist(nodes)
     r = []
     for b in repo.branches(nodes):
         r.append(wireprototypes.encodelist(b) + b"\n")
 
     return wireprototypes.bytesresponse(b''.join(r))
 
 
 @wireprotocommand(b'clonebundles', b'', permission=b'pull')
 def clonebundles(repo, proto):
     """Server command for returning info for available bundles to seed clones.
 
     Clients will parse this response and determine what bundle to fetch.
 
     Extensions may wrap this command to filter or dynamically emit data
     depending on the request. e.g. you could advertise URLs for the closest
     data center given the client's IP address.
     """
     return wireprototypes.bytesresponse(
         repo.vfs.tryread(bundlecaches.CB_MANIFEST_FILE)
     )
 
 
 wireprotocaps = [
     b'lookup',
     b'branchmap',
     b'pushkey',
     b'known',
     b'getbundle',
     b'unbundlehash',
 ]
 
 
 def _capabilities(repo, proto):
     """return a list of capabilities for a repo
 
     This function exists to allow extensions to easily wrap capabilities
     computation
 
     - returns a lists: easy to alter
     - change done here will be propagated to both `capabilities` and `hello`
       command without any other action needed.
     """
     # copy to prevent modification of the global list
     caps = list(wireprotocaps)
 
     # Command of same name as capability isn't exposed to version 1 of
     # transports. So conditionally add it.
     if commands.commandavailable(b'changegroupsubset', proto):
         caps.append(b'changegroupsubset')
 
     if streamclone.allowservergeneration(repo):
         if repo.ui.configbool(b'server', b'preferuncompressed'):
             caps.append(b'stream-preferred')
-        requiredformats = repo.requirements & repo.supportedformats
+        requiredformats = streamclone.streamed_requirements(repo)
         # if our local revlogs are just revlogv1, add 'stream' cap
         if not requiredformats - {requirementsmod.REVLOGV1_REQUIREMENT}:
             caps.append(b'stream')
         # otherwise, add 'streamreqs' detailing our local revlog format
         else:
             caps.append(b'streamreqs=%s' % b','.join(sorted(requiredformats)))
     if repo.ui.configbool(b'experimental', b'bundle2-advertise'):
         capsblob = bundle2.encodecaps(bundle2.getrepocaps(repo, role=b'server'))
         caps.append(b'bundle2=' + urlreq.quote(capsblob))
     caps.append(b'unbundle=%s' % b','.join(bundle2.bundlepriority))
 
     if repo.ui.configbool(b'experimental', b'narrow'):
         caps.append(wireprototypes.NARROWCAP)
         if repo.ui.configbool(b'experimental', b'narrowservebrokenellipses'):
             caps.append(wireprototypes.ELLIPSESCAP)
 
     return proto.addcapabilities(repo, caps)
 
 
 # If you are writing an extension and consider wrapping this function. Wrap
 # `_capabilities` instead.
 @wireprotocommand(b'capabilities', permission=b'pull')
 def capabilities(repo, proto):
     caps = _capabilities(repo, proto)
     return wireprototypes.bytesresponse(b' '.join(sorted(caps)))
 
 
 @wireprotocommand(b'changegroup', b'roots', permission=b'pull')
 def changegroup(repo, proto, roots):
     nodes = wireprototypes.decodelist(roots)
     outgoing = discovery.outgoing(
         repo, missingroots=nodes, ancestorsof=repo.heads()
     )
     cg = changegroupmod.makechangegroup(repo, outgoing, b'01', b'serve')
     gen = iter(lambda: cg.read(32768), b'')
     return wireprototypes.streamres(gen=gen)
 
 
 @wireprotocommand(b'changegroupsubset', b'bases heads', permission=b'pull')
 def changegroupsubset(repo, proto, bases, heads):
     bases = wireprototypes.decodelist(bases)
     heads = wireprototypes.decodelist(heads)
     outgoing = discovery.outgoing(repo, missingroots=bases, ancestorsof=heads)
     cg = changegroupmod.makechangegroup(repo, outgoing, b'01', b'serve')
     gen = iter(lambda: cg.read(32768), b'')
     return wireprototypes.streamres(gen=gen)
 
 
 @wireprotocommand(b'debugwireargs', b'one two *', permission=b'pull')
 def debugwireargs(repo, proto, one, two, others):
     # only accept optional args from the known set
     opts = options(b'debugwireargs', [b'three', b'four'], others)
     return wireprototypes.bytesresponse(
         repo.debugwireargs(one, two, **pycompat.strkwargs(opts))
     )
 
 
 def find_pullbundle(repo, proto, opts, clheads, heads, common):
     """Return a file object for the first matching pullbundle.
 
     Pullbundles are specified in .hg/pullbundles.manifest similar to
     clonebundles.
     For each entry, the bundle specification is checked for compatibility:
     - Client features vs the BUNDLESPEC.
     - Revisions shared with the clients vs base revisions of the bundle.
       A bundle can be applied only if all its base revisions are known by
       the client.
     - At least one leaf of the bundle's DAG is missing on the client.
     - Every leaf of the bundle's DAG is part of node set the client wants.
       E.g. do not send a bundle of all changes if the client wants only
       one specific branch of many.
     """
 
     def decodehexstring(s):
         return {binascii.unhexlify(h) for h in s.split(b';')}
 
     manifest = repo.vfs.tryread(b'pullbundles.manifest')
     if not manifest:
         return None
     res = bundlecaches.parseclonebundlesmanifest(repo, manifest)
     res = bundlecaches.filterclonebundleentries(repo, res)
     if not res:
         return None
     cl = repo.unfiltered().changelog
     heads_anc = cl.ancestors([cl.rev(rev) for rev in heads], inclusive=True)
     common_anc = cl.ancestors([cl.rev(rev) for rev in common], inclusive=True)
     compformats = clientcompressionsupport(proto)
     for entry in res:
         comp = entry.get(b'COMPRESSION')
         altcomp = util.compengines._bundlenames.get(comp)
         if comp and comp not in compformats and altcomp not in compformats:
             continue
         # No test yet for VERSION, since V2 is supported by any client
         # that advertises partial pulls
         if b'heads' in entry:
             try:
                 bundle_heads = decodehexstring(entry[b'heads'])
             except TypeError:
                 # Bad heads entry
                 continue
             if bundle_heads.issubset(common):
                 continue  # Nothing new
             if all(cl.rev(rev) in common_anc for rev in bundle_heads):
                 continue  # Still nothing new
             if any(
                 cl.rev(rev) not in heads_anc and cl.rev(rev) not in common_anc
                 for rev in bundle_heads
             ):
                 continue
         if b'bases' in entry:
             try:
                 bundle_bases = decodehexstring(entry[b'bases'])
             except TypeError:
                 # Bad bases entry
                 continue
             if not all(cl.rev(rev) in common_anc for rev in bundle_bases):
                 continue
         path = entry[b'URL']
         repo.ui.debug(b'sending pullbundle "%s"\n' % path)
         try:
             return repo.vfs.open(path)
         except IOError:
             repo.ui.debug(b'pullbundle "%s" not accessible\n' % path)
             continue
     return None
 
 
 @wireprotocommand(b'getbundle', b'*', permission=b'pull')
 def getbundle(repo, proto, others):
     opts = options(
         b'getbundle', wireprototypes.GETBUNDLE_ARGUMENTS.keys(), others
     )
     for k, v in pycompat.iteritems(opts):
         keytype = wireprototypes.GETBUNDLE_ARGUMENTS[k]
         if keytype == b'nodes':
             opts[k] = wireprototypes.decodelist(v)
         elif keytype == b'csv':
             opts[k] = list(v.split(b','))
         elif keytype == b'scsv':
             opts[k] = set(v.split(b','))
         elif keytype == b'boolean':
             # Client should serialize False as '0', which is a non-empty string
             # so it evaluates as a True bool.
             if v == b'0':
                 opts[k] = False
             else:
                 opts[k] = bool(v)
         elif keytype != b'plain':
             raise KeyError(b'unknown getbundle option type %s' % keytype)
 
     if not bundle1allowed(repo, b'pull'):
         if not exchange.bundle2requested(opts.get(b'bundlecaps')):
             if proto.name == b'http-v1':
                 return wireprototypes.ooberror(bundle2required)
             raise error.Abort(bundle2requiredmain, hint=bundle2requiredhint)
 
     try:
         clheads = set(repo.changelog.heads())
         heads = set(opts.get(b'heads', set()))
         common = set(opts.get(b'common', set()))
         common.discard(repo.nullid)
         if (
             repo.ui.configbool(b'server', b'pullbundle')
             and b'partial-pull' in proto.getprotocaps()
         ):
             # Check if a pre-built bundle covers this request.
             bundle = find_pullbundle(repo, proto, opts, clheads, heads, common)
             if bundle:
                 return wireprototypes.streamres(
                     gen=util.filechunkiter(bundle), prefer_uncompressed=True
                 )
 
         if repo.ui.configbool(b'server', b'disablefullbundle'):
             # Check to see if this is a full clone.
             changegroup = opts.get(b'cg', True)
             if changegroup and not common and clheads == heads:
                 raise error.Abort(
                     _(b'server has pull-based clones disabled'),
                     hint=_(b'remove --pull if specified or upgrade Mercurial'),
                 )
 
         info, chunks = exchange.getbundlechunks(
             repo, b'serve', **pycompat.strkwargs(opts)
         )
         prefercompressed = info.get(b'prefercompressed', True)
     except error.Abort as exc:
         # cleanly forward Abort error to the client
         if not exchange.bundle2requested(opts.get(b'bundlecaps')):
             if proto.name == b'http-v1':
                 return wireprototypes.ooberror(exc.message + b'\n')
             raise  # cannot do better for bundle1 + ssh
         # bundle2 request expect a bundle2 reply
         bundler = bundle2.bundle20(repo.ui)
         manargs = [(b'message', exc.message)]
         advargs = []
         if exc.hint is not None:
             advargs.append((b'hint', exc.hint))
         bundler.addpart(bundle2.bundlepart(b'error:abort', manargs, advargs))
         chunks = bundler.getchunks()
         prefercompressed = False
 
     return wireprototypes.streamres(
         gen=chunks, prefer_uncompressed=not prefercompressed
     )
 
 
 @wireprotocommand(b'heads', permission=b'pull')
 def heads(repo, proto):
     h = repo.heads()
     return wireprototypes.bytesresponse(wireprototypes.encodelist(h) + b'\n')
 
 
 @wireprotocommand(b'hello', permission=b'pull')
 def hello(repo, proto):
     """Called as part of SSH handshake to obtain server info.
 
     Returns a list of lines describing interesting things about the
     server, in an RFC822-like format.
 
     Currently, the only one defined is ``capabilities``, which consists of a
     line of space separated tokens describing server abilities:
 
         capabilities: <token0> <token1> <token2>
     """
     caps = capabilities(repo, proto).data
     return wireprototypes.bytesresponse(b'capabilities: %s\n' % caps)
 
 
 @wireprotocommand(b'listkeys', b'namespace', permission=b'pull')
 def listkeys(repo, proto, namespace):
     d = sorted(repo.listkeys(encoding.tolocal(namespace)).items())
     return wireprototypes.bytesresponse(pushkeymod.encodekeys(d))
 
 
 @wireprotocommand(b'lookup', b'key', permission=b'pull')
 def lookup(repo, proto, key):
     try:
         k = encoding.tolocal(key)
         n = repo.lookup(k)
         r = hex(n)
         success = 1
     except Exception as inst:
         r = stringutil.forcebytestr(inst)
         success = 0
     return wireprototypes.bytesresponse(b'%d %s\n' % (success, r))
 
 
 @wireprotocommand(b'known', b'nodes *', permission=b'pull')
 def known(repo, proto, nodes, others):
     v = b''.join(
         b and b'1' or b'0' for b in repo.known(wireprototypes.decodelist(nodes))
     )
     return wireprototypes.bytesresponse(v)
 
 
 @wireprotocommand(b'protocaps', b'caps', permission=b'pull')
 def protocaps(repo, proto, caps):
     if proto.name == wireprototypes.SSHV1:
         proto._protocaps = set(caps.split(b' '))
     return wireprototypes.bytesresponse(b'OK')
 
 
 @wireprotocommand(b'pushkey', b'namespace key old new', permission=b'push')
 def pushkey(repo, proto, namespace, key, old, new):
     # compatibility with pre-1.8 clients which were accidentally
     # sending raw binary nodes rather than utf-8-encoded hex
     if len(new) == 20 and stringutil.escapestr(new) != new:
         # looks like it could be a binary node
         try:
             new.decode('utf-8')
             new = encoding.tolocal(new)  # but cleanly decodes as UTF-8
         except UnicodeDecodeError:
             pass  # binary, leave unmodified
     else:
         new = encoding.tolocal(new)  # normal path
 
     with proto.mayberedirectstdio() as output:
         r = (
             repo.pushkey(
                 encoding.tolocal(namespace),
                 encoding.tolocal(key),
                 encoding.tolocal(old),
                 new,
             )
             or False
         )
 
     output = output.getvalue() if output else b''
     return wireprototypes.bytesresponse(b'%d\n%s' % (int(r), output))
 
 
 @wireprotocommand(b'stream_out', permission=b'pull')
 def stream(repo, proto):
     """If the server supports streaming clone, it advertises the "stream"
     capability with a value representing the version and flags of the repo
     it is serving. Client checks to see if it understands the format.
     """
     return wireprototypes.streamreslegacy(streamclone.generatev1wireproto(repo))
 
 
 @wireprotocommand(b'unbundle', b'heads', permission=b'push')
 def unbundle(repo, proto, heads):
     their_heads = wireprototypes.decodelist(heads)
 
     with proto.mayberedirectstdio() as output:
         try:
             exchange.check_heads(repo, their_heads, b'preparing changes')
             cleanup = lambda: None
             try:
                 payload = proto.getpayload()
                 if repo.ui.configbool(b'server', b'streamunbundle'):
 
                     def cleanup():
                         # Ensure that the full payload is consumed, so
                         # that the connection doesn't contain trailing garbage.
                         for p in payload:
                             pass
 
                     fp = util.chunkbuffer(payload)
                 else:
                     # write bundle data to temporary file as it can be big
                     fp, tempname = None, None
 
                     def cleanup():
                         if fp:
                             fp.close()
                         if tempname:
                             os.unlink(tempname)
 
                     fd, tempname = pycompat.mkstemp(prefix=b'hg-unbundle-')
                     repo.ui.debug(
                         b'redirecting incoming bundle to %s\n' % tempname
                     )
                     fp = os.fdopen(fd, pycompat.sysstr(b'wb+'))
                     for p in payload:
                         fp.write(p)
                     fp.seek(0)
 
                 gen = exchange.readbundle(repo.ui, fp, None)
                 if isinstance(
                     gen, changegroupmod.cg1unpacker
                 ) and not bundle1allowed(repo, b'push'):
                     if proto.name == b'http-v1':
                         # need to special case http because stderr do not get to
                         # the http client on failed push so we need to abuse
                         # some other error type to make sure the message get to
                         # the user.
                         return wireprototypes.ooberror(bundle2required)
                     raise error.Abort(
                         bundle2requiredmain, hint=bundle2requiredhint
                     )
 
                 r = exchange.unbundle(
                     repo, gen, their_heads, b'serve', proto.client()
                 )
                 if util.safehasattr(r, b'addpart'):
                     # The return looks streamable, we are in the bundle2 case
                     # and should return a stream.
                     return wireprototypes.streamreslegacy(gen=r.getchunks())
                 return wireprototypes.pushres(
                     r, output.getvalue() if output else b''
                 )
 
             finally:
                 cleanup()
 
         except (error.BundleValueError, error.Abort, error.PushRaced) as exc:
             # handle non-bundle2 case first
             if not getattr(exc, 'duringunbundle2', False):
                 try:
                     raise
                 except error.Abort as exc:
                     # The old code we moved used procutil.stderr directly.
                     # We did not change it to minimise code change.
                     # This need to be moved to something proper.
                     # Feel free to do it.
                     procutil.stderr.write(exc.format())
                     procutil.stderr.flush()
                     return wireprototypes.pushres(
                         0, output.getvalue() if output else b''
                     )
                 except error.PushRaced:
                     return wireprototypes.pusherr(
                         pycompat.bytestr(exc),
                         output.getvalue() if output else b'',
                     )
 
             bundler = bundle2.bundle20(repo.ui)
             for out in getattr(exc, '_bundle2salvagedoutput', ()):
                 bundler.addpart(out)
             try:
                 try:
                     raise
                 except error.PushkeyFailed as exc:
                     # check client caps
                     remotecaps = getattr(exc, '_replycaps', None)
                     if (
                         remotecaps is not None
                         and b'pushkey' not in remotecaps.get(b'error', ())
                     ):
                         # no support remote side, fallback to Abort handler.
                         raise
                     part = bundler.newpart(b'error:pushkey')
                     part.addparam(b'in-reply-to', exc.partid)
                     if exc.namespace is not None:
                         part.addparam(
                             b'namespace', exc.namespace, mandatory=False
                         )
                     if exc.key is not None:
                         part.addparam(b'key', exc.key, mandatory=False)
                     if exc.new is not None:
                         part.addparam(b'new', exc.new, mandatory=False)
                     if exc.old is not None:
                         part.addparam(b'old', exc.old, mandatory=False)
                     if exc.ret is not None:
                         part.addparam(b'ret', exc.ret, mandatory=False)
             except error.BundleValueError as exc:
                 errpart = bundler.newpart(b'error:unsupportedcontent')
                 if exc.parttype is not None:
                     errpart.addparam(b'parttype', exc.parttype)
                 if exc.params:
                     errpart.addparam(b'params', b'\0'.join(exc.params))
             except error.Abort as exc:
                 manargs = [(b'message', exc.message)]
                 advargs = []
                 if exc.hint is not None:
                     advargs.append((b'hint', exc.hint))
                 bundler.addpart(
                     bundle2.bundlepart(b'error:abort', manargs, advargs)
                 )
             except error.PushRaced as exc:
                 bundler.newpart(
                     b'error:pushraced',
                     [(b'message', stringutil.forcebytestr(exc))],
                 )
             return wireprototypes.streamreslegacy(gen=bundler.getchunks())