#!/usr/bin/python2
# -*- encoding: utf8 -*-
#
# The Qubes OS Project, http://www.qubes-os.org
#
# Copyright (C) 2010  Marek Marczykowski <marmarek@invisiblethingslab.com>
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
#
#
import fcntl

from optparse import OptionParser
from qubes.qubes import QubesVmCollection
import os.path
import os
import sys
import re
import subprocess

qvm_collection = None

def get_netvm_of_vm(vm):
    netvm = vm
    while netvm.netvm is not None:
        netvm = netvm.netvm
    if netvm is None or netvm.name == 'dom0':
        print >> sys.stderr, 'There seems to be no network connected to ClockVM, aborting.'
        sys.exit(1)
    return netvm

def main():
    parser = OptionParser()
    parser.add_option ("-v", "--verbose", action="store_true", dest="verbose", default=False)
    parser.add_option ("-f", "--force", action="store_true", dest="force", default=False)

    (options, args) = parser.parse_args ()

    lockfile_name = "/var/run/qubes/qvm-sync-clock.lock"
    if os.path.exists(lockfile_name):
        lockfile = open(lockfile_name, "r")
    else:
        lockfile = open(lockfile_name, "w")

    fcntl.fcntl(lockfile.fileno(), fcntl.F_SETFD, fcntl.FD_CLOEXEC)
    try:
        fcntl.flock(lockfile.fileno(), fcntl.LOCK_EX | fcntl.LOCK_NB)
    except IOError:
        print >>sys.stderr, "qvm-sync-clock already running, aborting"
        sys.exit(1)
    
    qvm_collection = QubesVmCollection()
    qvm_collection.lock_db_for_reading()
    qvm_collection.load()
    qvm_collection.unlock_db()

    clock_vm = qvm_collection.get_clockvm_vm()

    if clock_vm is None:
        print >> sys.stderr, 'There is no selected ClockVM, aborting.'
        sys.exit(1)

    if not clock_vm.is_running():
        print >> sys.stderr, 'ClockVM not started, exiting!'
        sys.exit(1)

    net_vm = get_netvm_of_vm(clock_vm)
    if options.verbose:
        print >> sys.stderr, '--> Waiting for network for ClockVM.'

    # Ignore retcode, try even if nm-online failed - user can setup network manually
    #  on-online has timeout 30sec by default
    net_vm.run('nm-online -x', verbose=options.verbose, gui=False, wait=True,
               ignore_stderr=True)

    # Sync clock
    if clock_vm.run('QUBESRPC qubes.SyncNtpClock dom0', user="root",
                    verbose=options.verbose, gui=False, wait=True, ignore_stderr=True) \
            != 0:
        if options.force:
            print >> sys.stderr, 'Time sync failed! - Syncing with dom0 ' \
                                 'anyway as requested'
        else:
            print >> sys.stderr, 'Time sync failed! - Exiting'
            sys.exit(1)
    else:
        # Use the date format based on RFC2822 to avoid localisation issues
        p = clock_vm.run('date -u -Iseconds', verbose=options.verbose,
                         gui=False, passio_popen=True, ignore_stderr=True)
        date_out = p.stdout.read(100)
        date_out = date_out.strip()
        if not re.match(r'^\d{4}-\d{2}-\d{2}T\d{2}:\d{2}:\d{2}\+0000$', date_out):
            print >> sys.stderr, 'Invalid date output, aborting!'
            sys.exit(1)

        # Sync dom0 time
        if options.verbose:
            print >> sys.stderr, '--> Syncing dom0 clock.'

        subprocess.check_call(['sudo', 'date', '-u', '-Iseconds', '-s', date_out],
                              stdout=None if options.verbose else open(os.devnull, 'w'))
        subprocess.check_call(['sudo', 'hwclock', '--systohc'],
                              stdout=None if options.verbose else open(os.devnull, 'w'))

    # Sync other VMs clock
    for vm in qvm_collection.values():
        if vm.is_running() and vm.qid != 0 and vm.qid != clock_vm.qid:
            if options.verbose:
                print >> sys.stderr, '--> Syncing \'%s\' clock.' % vm.name
            try:
                vm.run_service("qubes.SetDateTime", user="root",
                               localcmd="date -u -Iseconds")
            except Exception as e:
                print >> sys.stderr, "ERROR syncing time in VM '%s': %s" % (vm.name, str(e))
                pass

    # order is important!
    os.unlink(lockfile_name)
    lockfile.close()

main()