config/rebuild_check.py
author Petru Lingurar <petru.lingurar@softvision.ro>
Fri, 21 Dec 2018 08:56:47 +0000
changeset 501492 65621d0fe1262af0643cec37c23b2d9ec42588ad
parent 476323 da3c81f986fa63b42a2874b1791eddcdbfbe8424
permissions -rw-r--r--
Bug 1513938 - Enforce a Bundle size limit and drop `privateSession` if exceeds it. r=JanH, a=jcristau The `privateSession` key would normally allow persisting the Private Browsing session across OOMs in Activity's Bundle. We need to do that to avoid storing private, sensible data on disk like we do with the normal browsing session. In some cases `privateSession` would contain a lot of data which, along with other possible concurrent transactions could overflow Binder's buffer which has a limited fixed size, currently 1Mb. To avoid this, we will drop `privateSession` from the Bundle if the resulting size is greater than a _speculative_ size of 300KBs which would mean that in the case of an OOM all Private Browsing state would be lost. Bug 1515592 is filed to investigate for a better solution. Differential Revision: https://phabricator.services.mozilla.com/D15067

# This Source Code Form is subject to the terms of the Mozilla Public
# License, v. 2.0. If a copy of the MPL was not distributed with this
# file, You can obtain one at http://mozilla.org/MPL/2.0/.

import os
import errno


def mtime(path):
    try:
        return os.stat(path).st_mtime
    except OSError as e:
        if e.errno == errno.ENOENT:
            return -1
        raise


def rebuild_check(args):
    target = args[0]
    deps = args[1:]
    t = mtime(target)
    if t < 0:
        print(target)
        return

    newer = []
    removed = []
    for dep in deps:
        deptime = mtime(dep)
        if deptime < 0:
            removed.append(dep)
        elif mtime(dep) > t:
            newer.append(dep)

    if newer and removed:
        print('Rebuilding %s because %s changed and %s was removed' % (
            target, ', '.join(newer), ', '.join(removed)))
    elif newer:
        print('Rebuilding %s because %s changed' % (target, ', '.join(newer)))
    elif removed:
        print('Rebuilding %s because %s was removed' % (
            target, ', '.join(removed)))
    else:
        print('Rebuilding %s for an unknown reason' % target)


if __name__ == '__main__':
    import sys
    rebuild_check(sys.argv[1:])