#!/usr/bin/env python
#
# $Id$
#
# Copyright (C) 2015-2016  Parsons Government Services ("PARSONS")
# Portions copyright (C) 2014  Dragon Research Labs ("DRL")
# Portions copyright (C) 2013  Internet Systems Consortium ("ISC")
#
# Permission to use, copy, modify, and distribute this software for any
# purpose with or without fee is hereby granted, provided that the above
# copyright notices and this permission notice appear in all copies.
#
# THE SOFTWARE IS PROVIDED "AS IS" AND PARSONS, DRL, AND ISC DISCLAIM
# ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED
# WARRANTIES OF MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL
# PARSONS, DRL, OR ISC BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR
# CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
# OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
# NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
# WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

"""
Cron job for rcynic and rpki-rtr in stock configuration.

Locking code here works like FreeBSD's lockf(1) utility given -k and
-t 0 options, which is both the sanest and simplest combination for
our purposes.  In theory this is portable to any Unix-like system.
"""

import os
import sys
import fcntl
import errno
import rpki.autoconf

def run(*cmd, **kwargs):
    cwd = kwargs.pop("cwd", None)
    pid = os.fork()
    if pid == 0:
        if cwd is not None:
            os.chdir(cwd)
        os.closerange(3, os.sysconf("SC_OPEN_MAX"))
        os.execvp(cmd[0], cmd)
        os._exit(1)                     # pylint: disable=W0212
    else:
        status = os.waitpid(pid, 0)[1]
        if status == 0:
            return
        elif os.WIFSIGNALED(status):
            sys.exit("Process %s exited with signal %s" % (" ".join(cmd), os.WTERMSIG(status)))
        elif os.WIFEXITED(status):
            sys.exit("Program %s exited with status %s" % (" ".join(cmd), os.WEXITSTATUS(status)))
        else:
            sys.exit("Program %s exited for unknown reason %s" % (" ".join(cmd), status))

try:
    lock = os.open(os.path.join(rpki.autoconf.RCYNIC_DIR, "data", "lock"),
                   os.O_RDONLY | os.O_CREAT | os.O_NONBLOCK, 0666)
    fcntl.flock(lock, fcntl.LOCK_EX | fcntl.LOCK_NB)
except (IOError, OSError), e:
    if e.errno == errno.EAGAIN:
        sys.exit(0)                         # Another instance of this script is already running, exit silently
    else:
        sys.exit("Error %r opening lock %r" % (e.strerror, os.path.join(rpki.autoconf.RCYNIC_DIR, "data/lock")))

run(os.path.join(rpki.autoconf.bindir, "rcynic"))

run(os.path.join(rpki.autoconf.bindir, "rpki-rtr"),
    "cronjob",
    cwd = os.path.join(rpki.autoconf.RCYNIC_DIR, "rpki-rtr"))

prog = os.path.join(rpki.autoconf.libexecdir, "rpkigui-rcynic")
if os.path.exists(prog):
    run(prog)

if rpki.autoconf.RCYNIC_HTML_DIR and os.path.exists(os.path.dirname(rpki.autoconf.RCYNIC_HTML_DIR)):
    run(os.path.join(rpki.autoconf.bindir, "rcynic-html"),
        os.path.join(rpki.autoconf.RCYNIC_DIR, "data/rcynic.xml"),
        rpki.autoconf.RCYNIC_HTML_DIR)