comparison mercurial/revlogutils/nodemap.py @ 44322:72c15641c8b4

nodemap: introduce an explicit class/object for the docket

We are about to add more information to this docket, having a clear location to
stock them in memory will help.

Differential Revision: https://phab.mercurial-scm.org/D7884

44321:f0862ee1a31e

    offset = 0
    (version,) = S_VERSION.unpack(pdata[offset : offset + S_VERSION.size])
    if version != ONDISK_VERSION:
        return None
    offset += S_VERSION.size
    (uuid_size,) = S_HEADER.unpack(pdata[offset : offset + S_HEADER.size])
    offset += S_HEADER.size
    uid = pdata[offset : offset + uuid_size]

    filename = _rawdata_filepath(revlog, uid)
    return revlog.opener.tryread(filename)


def setup_persistent_nodemap(tr, revlog):
    """Install whatever is needed transaction side to persist a nodemap on disk

        raise error.ProgrammingError(msg)
    if util.safehasattr(revlog.index, "nodemap_data_all"):
        data = revlog.index.nodemap_data_all()
    else:
        data = persistent_data(revlog.index)
    uid = _make_uid()
    datafile = _rawdata_filepath(revlog, uid)
    olds = _other_rawdata_filepath(revlog, uid)
    if olds:
        realvfs = getattr(revlog, '_realopener', revlog.opener)

        def cleanup(tr):
            for oldfile in olds:

    with revlog.opener(datafile, b'w') as fd:
        fd.write(data)
    # EXP-TODO: if this is a cache, this should use a cache vfs, not a
    # store vfs
    with revlog.opener(revlog.nodemap_file, b'w', atomictemp=True) as fp:
        fp.write(_serialize_docket(uid))
    # EXP-TODO: if the transaction abort, we should remove the new data and
    # reinstall the old one.


### Nodemap docket file

    The identifier is random and composed of ascii characters."""
    return nodemod.hex(os.urandom(ID_SIZE))


def _serialize_docket(uid):
    """return serialized bytes for a docket using the passed uid"""
    data = []
    data.append(S_VERSION.pack(ONDISK_VERSION))
    data.append(S_HEADER.pack(len(uid)))
    data.append(uid)
    return b''.join(data)


def _rawdata_filepath(revlog, uid):
    """The (vfs relative) nodemap's rawdata file for a given uid"""
    prefix = revlog.nodemap_file[:-2]
    return b"%s-%s.nd" % (prefix, uid)


def _other_rawdata_filepath(revlog, uid):
    prefix = revlog.nodemap_file[:-2]
    pattern = re.compile(b"(^|/)%s-[0-9a-f]+\.nd$" % prefix)
    new_file_path = _rawdata_filepath(revlog, uid)
    new_file_name = revlog.opener.basename(new_file_path)
    dirpath = revlog.opener.dirname(new_file_path)
    others = []
    for f in revlog.opener.listdir(dirpath):
        if pattern.match(f) and f != new_file_name:

44322:72c15641c8b4

    offset = 0
    (version,) = S_VERSION.unpack(pdata[offset : offset + S_VERSION.size])
    if version != ONDISK_VERSION:
        return None
    offset += S_VERSION.size
    (uid_size,) = S_HEADER.unpack(pdata[offset : offset + S_HEADER.size])
    offset += S_HEADER.size
    docket = NodeMapDocket(pdata[offset : offset + uid_size])

    filename = _rawdata_filepath(revlog, docket)
    return revlog.opener.tryread(filename)


def setup_persistent_nodemap(tr, revlog):
    """Install whatever is needed transaction side to persist a nodemap on disk

        raise error.ProgrammingError(msg)
    if util.safehasattr(revlog.index, "nodemap_data_all"):
        data = revlog.index.nodemap_data_all()
    else:
        data = persistent_data(revlog.index)
    target_docket = NodeMapDocket()
    datafile = _rawdata_filepath(revlog, target_docket)
    olds = _other_rawdata_filepath(revlog, target_docket)
    if olds:
        realvfs = getattr(revlog, '_realopener', revlog.opener)

        def cleanup(tr):
            for oldfile in olds:

    with revlog.opener(datafile, b'w') as fd:
        fd.write(data)
    # EXP-TODO: if this is a cache, this should use a cache vfs, not a
    # store vfs
    with revlog.opener(revlog.nodemap_file, b'w', atomictemp=True) as fp:
        fp.write(target_docket.serialize())
    # EXP-TODO: if the transaction abort, we should remove the new data and
    # reinstall the old one.


### Nodemap docket file

    The identifier is random and composed of ascii characters."""
    return nodemod.hex(os.urandom(ID_SIZE))


class NodeMapDocket(object):
    """metadata associated with persistent nodemap data

    The persistent data may come from disk or be on their way to disk.
    """

    def __init__(self, uid=None):
        if uid is None:
            uid = _make_uid()
        self.uid = uid

    def copy(self):
        return NodeMapDocket(uid=self.uid)

    def serialize(self):
        """return serialized bytes for a docket using the passed uid"""
        data = []
        data.append(S_VERSION.pack(ONDISK_VERSION))
        data.append(S_HEADER.pack(len(self.uid)))
        data.append(self.uid)
        return b''.join(data)


def _rawdata_filepath(revlog, docket):
    """The (vfs relative) nodemap's rawdata file for a given uid"""
    prefix = revlog.nodemap_file[:-2]
    return b"%s-%s.nd" % (prefix, docket.uid)


def _other_rawdata_filepath(revlog, docket):
    prefix = revlog.nodemap_file[:-2]
    pattern = re.compile(b"(^|/)%s-[0-9a-f]+\.nd$" % prefix)
    new_file_path = _rawdata_filepath(revlog, docket)
    new_file_name = revlog.opener.basename(new_file_path)
    dirpath = revlog.opener.dirname(new_file_path)
    others = []
    for f in revlog.opener.listdir(dirpath):
        if pattern.match(f) and f != new_file_name: