view hgext/remotefilelog/shallowbundle.py @ 42961:460f8bf58020

osutil: allow disabling setprocname via a define passed to the compiler

In some situations, we run a custom python launcher that appears to not set up
Py_GetArgcArgv correctly. We then proceed to promptly crash when we attempt to
dereference NULL. Being able to completely disable setprocname is beneficial in
these situations, since we won't even attempt to use it, even if the case that
causes the crash is fixed.

Right now, if I compile osutil.so with -DSETPROCNAME_USE_NONE, the compilation
fails on python3 due to SETPROCNAME_USE_NONE redefinition. I could possibly
work around that, but it's likely helpful to have a way of disabling this
completely without it being brittle (i.e. if python3 ever gains the ability to
perform this operation).

Differential Revision: https://phab.mercurial-scm.org/D6865

# shallowbundle.py - bundle10 implementation for use with shallow repositories
#
# Copyright 2013 Facebook, Inc.
#
# 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

from mercurial.i18n import _
from mercurial.node import bin, hex, nullid
from mercurial import (
    bundlerepo,
    changegroup,
    error,
    match,
    mdiff,
    pycompat,
)
from . import (
    constants,
    remotefilelog,
    shallowutil,
)

NoFiles = 0
LocalFiles = 1
AllFiles = 2

def shallowgroup(cls, self, nodelist, rlog, lookup, units=None, reorder=None):
    if not isinstance(rlog, remotefilelog.remotefilelog):
        for c in super(cls, self).group(nodelist, rlog, lookup,
                                        units=units):
            yield c
        return

    if len(nodelist) == 0:
        yield self.close()
        return

    nodelist = shallowutil.sortnodes(nodelist, rlog.parents)

    # add the parent of the first rev
    p = rlog.parents(nodelist[0])[0]
    nodelist.insert(0, p)

    # build deltas
    for i in pycompat.xrange(len(nodelist) - 1):
        prev, curr = nodelist[i], nodelist[i + 1]
        linknode = lookup(curr)
        for c in self.nodechunk(rlog, curr, prev, linknode):
            yield c

    yield self.close()

class shallowcg1packer(changegroup.cgpacker):
    def generate(self, commonrevs, clnodes, fastpathlinkrev, source):
        if shallowutil.isenabled(self._repo):
            fastpathlinkrev = False

        return super(shallowcg1packer, self).generate(commonrevs, clnodes,
            fastpathlinkrev, source)

    def group(self, nodelist, rlog, lookup, units=None, reorder=None):
        return shallowgroup(shallowcg1packer, self, nodelist, rlog, lookup,
                            units=units)

    def generatefiles(self, changedfiles, *args):
        try:
            linknodes, commonrevs, source = args
        except ValueError:
            commonrevs, source, mfdicts, fastpathlinkrev, fnodes, clrevs = args
        if shallowutil.isenabled(self._repo):
            repo = self._repo
            if isinstance(repo, bundlerepo.bundlerepository):
                # If the bundle contains filelogs, we can't pull from it, since
                # bundlerepo is heavily tied to revlogs. Instead require that
                # the user use unbundle instead.
                # Force load the filelog data.
                bundlerepo.bundlerepository.file(repo, 'foo')
                if repo._cgfilespos:
                    raise error.Abort("cannot pull from full bundles",
                                      hint="use `hg unbundle` instead")
                return []
            filestosend = self.shouldaddfilegroups(source)
            if filestosend == NoFiles:
                changedfiles = list([f for f in changedfiles
                                     if not repo.shallowmatch(f)])

        return super(shallowcg1packer, self).generatefiles(
            changedfiles, *args)

    def shouldaddfilegroups(self, source):
        repo = self._repo
        if not shallowutil.isenabled(repo):
            return AllFiles

        if source == "push" or source == "bundle":
            return AllFiles

        caps = self._bundlecaps or []
        if source == "serve" or source == "pull":
            if constants.BUNDLE2_CAPABLITY in caps:
                return LocalFiles
            else:
                # Serving to a full repo requires us to serve everything
                repo.ui.warn(_("pulling from a shallow repo\n"))
                return AllFiles

        return NoFiles

    def prune(self, rlog, missing, commonrevs):
        if not isinstance(rlog, remotefilelog.remotefilelog):
            return super(shallowcg1packer, self).prune(rlog, missing,
                commonrevs)

        repo = self._repo
        results = []
        for fnode in missing:
            fctx = repo.filectx(rlog.filename, fileid=fnode)
            if fctx.linkrev() not in commonrevs:
                results.append(fnode)
        return results

    def nodechunk(self, revlog, node, prevnode, linknode):
        prefix = ''
        if prevnode == nullid:
            delta = revlog.rawdata(node)
            prefix = mdiff.trivialdiffheader(len(delta))
        else:
            # Actually uses remotefilelog.revdiff which works on nodes, not revs
            delta = revlog.revdiff(prevnode, node)
        p1, p2 = revlog.parents(node)
        flags = revlog.flags(node)
        meta = self.builddeltaheader(node, p1, p2, prevnode, linknode, flags)
        meta += prefix
        l = len(meta) + len(delta)
        yield changegroup.chunkheader(l)
        yield meta
        yield delta

def makechangegroup(orig, repo, outgoing, version, source, *args, **kwargs):
    if not shallowutil.isenabled(repo):
        return orig(repo, outgoing, version, source, *args, **kwargs)

    original = repo.shallowmatch
    try:
        # if serving, only send files the clients has patterns for
        if source == 'serve':
            bundlecaps = kwargs.get(r'bundlecaps')
            includepattern = None
            excludepattern = None
            for cap in (bundlecaps or []):
                if cap.startswith("includepattern="):
                    raw = cap[len("includepattern="):]
                    if raw:
                        includepattern = raw.split('\0')
                elif cap.startswith("excludepattern="):
                    raw = cap[len("excludepattern="):]
                    if raw:
                        excludepattern = raw.split('\0')
            if includepattern or excludepattern:
                repo.shallowmatch = match.match(repo.root, '', None,
                    includepattern, excludepattern)
            else:
                repo.shallowmatch = match.always()
        return orig(repo, outgoing, version, source, *args, **kwargs)
    finally:
        repo.shallowmatch = original

def addchangegroupfiles(orig, repo, source, revmap, trp, expectedfiles, *args):
    if not shallowutil.isenabled(repo):
        return orig(repo, source, revmap, trp, expectedfiles, *args)

    newfiles = 0
    visited = set()
    revisiondatas = {}
    queue = []

    # Normal Mercurial processes each file one at a time, adding all
    # the new revisions for that file at once. In remotefilelog a file
    # revision may depend on a different file's revision (in the case
    # of a rename/copy), so we must lay all revisions down across all
    # files in topological order.

    # read all the file chunks but don't add them
    progress = repo.ui.makeprogress(_('files'), total=expectedfiles)
    while True:
        chunkdata = source.filelogheader()
        if not chunkdata:
            break
        f = chunkdata["filename"]
        repo.ui.debug("adding %s revisions\n" % f)
        progress.increment()

        if not repo.shallowmatch(f):
            fl = repo.file(f)
            deltas = source.deltaiter()
            fl.addgroup(deltas, revmap, trp)
            continue

        chain = None
        while True:
            # returns: (node, p1, p2, cs, deltabase, delta, flags) or None
            revisiondata = source.deltachunk(chain)
            if not revisiondata:
                break

            chain = revisiondata[0]

            revisiondatas[(f, chain)] = revisiondata
            queue.append((f, chain))

            if f not in visited:
                newfiles += 1
                visited.add(f)

        if chain is None:
            raise error.Abort(_("received file revlog group is empty"))

    processed = set()
    def available(f, node, depf, depnode):
        if depnode != nullid and (depf, depnode) not in processed:
            if not (depf, depnode) in revisiondatas:
                # It's not in the changegroup, assume it's already
                # in the repo
                return True
            # re-add self to queue
            queue.insert(0, (f, node))
            # add dependency in front
            queue.insert(0, (depf, depnode))
            return False
        return True

    skipcount = 0

    # Prefetch the non-bundled revisions that we will need
    prefetchfiles = []
    for f, node in queue:
        revisiondata = revisiondatas[(f, node)]
        # revisiondata: (node, p1, p2, cs, deltabase, delta, flags)
        dependents = [revisiondata[1], revisiondata[2], revisiondata[4]]

        for dependent in dependents:
            if dependent == nullid or (f, dependent) in revisiondatas:
                continue
            prefetchfiles.append((f, hex(dependent)))

    repo.fileservice.prefetch(prefetchfiles)

    # Apply the revisions in topological order such that a revision
    # is only written once it's deltabase and parents have been written.
    while queue:
        f, node = queue.pop(0)
        if (f, node) in processed:
            continue

        skipcount += 1
        if skipcount > len(queue) + 1:
            raise error.Abort(_("circular node dependency"))

        fl = repo.file(f)

        revisiondata = revisiondatas[(f, node)]
        # revisiondata: (node, p1, p2, cs, deltabase, delta, flags)
        node, p1, p2, linknode, deltabase, delta, flags = revisiondata

        if not available(f, node, f, deltabase):
            continue

        base = fl.rawdata(deltabase)
        text = mdiff.patch(base, delta)
        if not isinstance(text, bytes):
            text = bytes(text)

        meta, text = shallowutil.parsemeta(text)
        if 'copy' in meta:
            copyfrom = meta['copy']
            copynode = bin(meta['copyrev'])
            if not available(f, node, copyfrom, copynode):
                continue

        for p in [p1, p2]:
            if p != nullid:
                if not available(f, node, f, p):
                    continue

        fl.add(text, meta, trp, linknode, p1, p2)
        processed.add((f, node))
        skipcount = 0

    progress.complete()

    return len(revisiondatas), newfiles