#!/usr/bin/env python
# $Id: hbd,v 1.38 2013/07/14 02:25:05 andreas Exp $
# Wait for heartbeat messages and act on them (or their absence)
#
VER = 2.00

import time
import os
import string
import sys
import socket
import atexit
import select
import SocketServer
import BaseHTTPServer
import getopt
import signal
import cPickle
import smtplib
import traceback
import urllib
import httplib
import threading

from subprocess import Popen, STDOUT, PIPE


SEND_EMAIL=False
SEND_PUSHOVER=True

DEBUG = 0

LOGFILE = "/home/andreas/public_html/messages/andreas"
PICKFILE = "/var/tmp/hbd.pick"
AEMAIL = ["andreas@wrede.ca"]
NAME = "heatbeat"
SMTPSERVER = "localhost"

hosts = {}
htab = {}

msgs = []

num = 0
#AEW upcount = 0
PORT = 50003
TPORT = 50004
THOST = ""

verbose = False

INTERVAL = 10
GRACE = 2

os.environ['TZ'] = 'EST5EDT'

tsfm=["%H","%d","%U"]
lastfm=["","",""]

def handler(signum, frame):
	global running, sig
	sig = signum
	if not running:
		if verbose:
			sys.stderr.write("NOT runing signal: %s running: %d" % (sig, running))
		sys.exit(2)
	if verbose:
		sys.stderr.write("signal: %s running: %s frame: %s" % (sig, running, frame))


def shortname(name):
	r = string.split(name, '.')
	return r[0]


class NullDevice:
	def write(self, s):
		pass

class Addr:
	def __init__(self, a4, a6):
		self.a4 = a4
		self.a6 = a6



class Host:
	up = "up"
	down = "down"
	overdue = "overdue"

	def __init__(self, name, addr):
		global num
		self.name = shortname(name)
		self.addr = addr
		self.num = num
		self.lastbeat = time.time()
		self.upcount = 0
		self.state = Host.up
		self.state = "up"
		self.statetime = self.lastbeat
		self.interval = 0
		self.doesack = -1
		self.cmds = []
		self.hdwcounts = [[0,0],[0,0],[0,0]]
		num += 1


	# called when reloading class from pickle, add new fields here
	def fixup(self):
		try:
			a=self.cmds
		except:
			self.cmds=[]

		try:
			a=self.hdwcounts
		except:
			self.hdwcounts = [[self.doesack,self.upcount],[self.doesack,self.upcount],[self.doesack,self.upcount]]

	def getstate(self):
		return self.state

	def dispstate(self):
		if self.state in ["down", "overdue"]:
			state = "<b>%s</b>" % self.state
		else:
			state = "%s" % self.state
		return state

	def dispstats(self):
		if self.doesack != -1:
			if self.upcount > 0:
#				return "(%0.1f%%) %s %s %s " % ((self.doesack * 100.0) / self.upcount, self.doesack, self.upcount, self.hdwcounts)
				r = ""
				for v in xrange(3):
					a,u = self.hdwcounts[v]
					if (self.upcount - u) != 0:
						vs = "%0.0f" % (100.0 - (((self.doesack - a) * 100.0) / (self.upcount - u)))
						if vs == "0":
							vs=""
					else:
						vs="-"
					r+= '<td align="right">%s</td>' % vs
				return r
			else:
				return "<td>(%s)</td><td></td><td></td>" % (self.doesack)
		return '<td align="right">N/A</td><td></td<td></td>>'

	# set new state, return number of secs in previous state
	def newstate(self, state, when=0):
		self.state = state
		now = time.time()-when
		s = now-self.statetime
		self.statetime = now
		return s


def email(s, msg):
	if not SEND_EMAIL:
		return
	ret = "OK"
	toaddrs = AEMAIL
	fromaddr = "aew.heartbeat@wrede.ca"
	subj = "Info from %s: %s" % (NAME, s)
	date = time.strftime("%a, %d %b %Y %H:%M:%S %z", time.localtime())
	body = "To: %s\nFrom: %s\nSubject: %s\nDate: %s\n\n%s" % (toaddrs[0], fromaddr, subj, date, msg)
	try:
		server = smtplib.SMTP(SMTPSERVER)
		if DEBUG > 0: server.set_debuglevel(1)
		server.sendmail(fromaddr, toaddrs, body)
	except smtplib.SMTPRecipientsRefused, errs:
		log("cannot send email: %s\n" % (errs))
		ret = "Fail"
	except:
		print("smtp error: "+traceback.format_exc())
		saveandrestart()
	try:
		server.quit()
	except:
		pass
	return ret


def pushover(msg):
	if not SEND_PUSHOVER:
		return
	conn = httplib.HTTPSConnection("api.pushover.net:443")
	try:
		conn.request("POST", "/1/messages.json",
			urllib.urlencode({
			"token": "ac7NLX2rPjXFareeDgLpXNoDf4iFmf",
			"user": "uDhH33UjQQDYtNzJb1ThRiWb9ingGK",
			"message": msg, }), { "Content-type": "application/x-www-form-urlencoded" })
		conn.getresponse()
	except:
		pass


# nsupdate:  set the DNS A record for a fqdn
#	return: None if ok, else error text
def nsupdate(hostname, newip):
	u = {}
	D['domain'] = 'dy.wapanafa.org'
	D['fqdn'] = '%s.dy.wapanafa.org' % hostname
	D['dnsttl'] = '5'
	D['newip'] = newip
	D['ts'] = time.strftime('%Y-%m-%d.%H:%M:%S', time.gmtime())
	if newip.find(":") > 0:
		nsup = """update delete %(fqdn)s AAAA
update add %(fqdn)s %(dnsttl)s AAAA %(newip)s
update delete %(fqdn)s TXT
update add %(fqdn)s %(dnsttl)s TXT "Created: %(ts)s"
send
answer

""" % D
	else:
		nsup = """update delete %(fqdn)s A
update add %(fqdn)s %(dnsttl)s A %(newip)s
update delete %(fqdn)s TXT
update add %(fqdn)s %(dnsttl)s TXT "Created: %(ts)s"
send
answer

""" % D

	if DEBUG > 0: log("DBG: nsup %s" % nsup)
	cmd = ["/usr/local/bin/nsupdate", "-k", "/etc/dhcpc/K%(domain)s.+157+00000." % D, "-v"]
	if DEBUG > 0: log("DBG: cmd %s" % cmd)
	try:
		p = Popen(cmd, shell=False, bufsize=1, stdin=PIPE, stdout=PIPE, stderr=STDOUT)
	except OSError, e:
		return "nsupdate: execution failed: %s" % e
	except:
		return "nsupdate: some error occured"

	(output, err) = p.communicate(nsup)
	if output.find('status: NOERROR') >= 0:
		return None
	return output


#
def dur(sec):
	sec = int(sec)
	h = sec / 3600
	m = (sec - h * 3600) / 60
	s = (sec - h * 3600) % 60
	if h > 0:
		return "%d:%02d:%02d" % (h, m, s)
	if m > 0:
		return "%d:%02d" % (m, s)
	return "0:%02d" % s


#
def addhost(name, addr):
	sname = shortname(name)
	if sname in hosts:		# was: hosts.has_key(sname):
		del htab[hosts[sname].addr]
		hosts[sname].addr = addr
		htab[addr] = sname
		m = "%s, changed address to %s" % (sname, addr)
		log(m)
	else:
		hosts[sname] = Host(sname, addr)
		s = hosts.keys()
		s.sort()
		x = 0
		for n in s:
			hosts[n].num = x
			x += 1
		htab[addr] = sname


#
def on_exit():
	if DEBUG > 0: sys.stderr.write("on_exit\n")
	try:
		logf.close()
	except:
		pass
	print "exit"


def initlog(logfile):
	return open(logfile, "a")


#
#
def checkoverdue():

	for h in hosts.keys():
		if hosts[h].state == Host.down:
			continue
		timeout = hosts[h].interval+grace
		if hosts[h].state == Host.up and now-hosts[h].lastbeat > timeout:
			m = "%s is overdue" % h
			if h in watchhosts:
				email("overdue", m)
				pushover(m)
			hosts[h].newstate(Host.overdue, grace)
			log(m)


def log(m, service="heartbeat"):
	if DEBUG > 0: print "Log: %s" % m
	msg = time.strftime("%b %d %H:%M:%S", time.localtime(time.time()))+": "+m+"\n"
	msgs.append(msg)
	if logfmt == "msg":
		m2 = "%d|%s|%s\n" % (now, service, m)
	else:
		m2 = msg
	logf.write(m2)
	logf.flush()
	pickleit()


#
#
def fromaddr(name, addr, boot, interval, acks):
	global htab


	newh=False
	if not name in hosts:		# was: hosts.has_key(name):
		addhost(name, addr)
		newh=True
	host = hosts[name]
	host.doesack = acks
	if host.addr != addr:
		if host.addr in htab:		# was: htab.has_key(host.addr):
			del htab[host.addr]
		host.addr = addr
		htab[addr] = name
		m = "%s changed address to %s" % (host.name, addr)
		if name in dyndnshosts and not ":" in addr:	# don't try and cat ptr to IPv6 addr
			err = nsupdate(name, addr)
			if err:
				m += ", DNS failed: %s" % err
				email("error: nsupdate failed", m)
			else:
				m += ", DNS updated."
		log(m)
		if name in watchhosts:
			email("address change", m)
			pushover(m)

	host.lastbeat = now
	if host.getstate() != Host.up and interval > 0:
		lasts = host.state
		d = host.newstate(Host.up)
		m = "%s, back after being %s for %s" % (host.name, lasts, dur(d))
		log(m)
		if name in watchhosts:
			email("back", name)
			pushover("%s is back" % name)
	if boot or newh:
		host.upcount = host.doesack
	else:
		host.upcount += 1


#
#
def readsock(sock):
	global htab
	if DEBUG > 3: sys.stderr.write("readsock recfrom start")
	data, addr = sock.recvfrom(1024)
	if DEBUG > 2: sys.stderr.write("readsock = %s, %s\n" % (data,addr))
	pairs = string.split(data, ';')
	boot = 0
	shutdown = 0
	name = "unknown"
	service = "unknown"
	msg = None
	interval = 0
	deltaT = 0.0
	acks = -1
	for pair in pairs:
		l = string.split(pair, "=")
		key = l[0]
		if len(l) != 2:
			val = "0"
		else:
			val = l[1]
		if key == 'boot':
			boot += 1
		elif key == 'shutdown':
			shutdown += 1
		elif key == 'interval':
			interval = int(val)
		elif key == 'name':
			name = shortname(val)
		elif key == 'msg':
			msg = val
		elif key == 'service':
			service = val
		elif key == 'time':
			try:
				deltaT = now-float(val)
			except:
				pass
		elif key == 'acks':
			try:
				acks = int(val)
			except:
				acks = -1

	if boot:
		if acks == -1:
			a = "(%s)" % acks
		else:
			a = ""
		m = "%s booted, deltaT %0.2g sec %s" % (name, deltaT, a)
		log(m)
		if name in watchhosts:
			email("booted", m)
			pushover(m)
	if msg:
		m = "%s msg: %s" % (name, msg)
		log(m, service=service)
		if name in watchhosts:
			email("msg", m)
			pushover(m)

	fromaddr(name, addr[0], boot, interval, acks)
	if shutdown:
		m = "%s shutdown" % name
		log(m)
		if name in watchhosts:
			email("shutdown", m)
			pushover(m)
		try:
			hosts[name].newstate(Host.down)
		except:
			pass
	if interval > 0:
		try:
			hosts[name].interval = interval
		except:
			pass

	rmsg="ACK"
	if len(hosts[name].cmds):
		rmsg=hosts[name].cmds[0]
		msg="command '%s' initiated" %  hosts[name].cmds[0]
		email("%s cmd exec" % name, msg)
		pushover(msg)
		del hosts[name].cmds[0]
		log("%s command initiated" % name)
	try:
		ss=sock.sendto(rmsg, addr)
		if DEBUG > 2: print "msg from %s,%s, sent %s bytes back" % (addr[0], addr[1], ss)
	except:
		pass


#
#

#class HttpServer(BaseHTTPServer.HTTPServer):
class HttpServer(SocketServer.ThreadingMixIn, BaseHTTPServer.HTTPServer):
	allow_reuse_address = True
	def threaded():
		pass
#
#
class HttpHandler(BaseHTTPServer.BaseHTTPRequestHandler):


	def do_HEAD(self):
		self.send_response(200)
		self.send_header("Last-Modified", time.strftime("%a, %d %b %Y %H:%M:%S GMT", time.gmtime(now)))
#		self.send_header("Accept-Ranges","bytes")
#		self.send_header("Connection","close")
		self.send_header("Content-Type","text/html; charset = ISO-8859-1")
		self.end_headers()
	

	def buildhead(self, title="Heartbeat", refresh=None):
		res=[]
		res.append('<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">')
		res.append("<html>")
		res.append("<head>")
		res.append('<title>%s</title>' % (title))
		if refresh:
			res.append("<meta http-equiv = Refresh content = %d>\n" % refresh)
		res.append("</head>")
		res.append('<body BGCOLOR = "#FFFFFF" LINK = "#008000" VLINK = "#008000">')
		return res


	def buildpage(self):
		res=self.buildhead(refresh=60)
		res.append("<H2>Heartbeat status %s</h2><h4> %s (%s)</H4>" % (VER, time.strftime("%H:%M:%S", time.localtime(now)), os.environ.get('TZ', 'CET-1CDT')))
		res.append("<table>")
		res.append("<tr><th>Host</th><th>State</th><th>Hr</th><th>Dy</th><th>Wk</th><th>IP Addr</th><th>Last change</th></tr>\n")
		hosts_sorted = hosts.keys()
		hosts_sorted.sort()
		for h in hosts_sorted:
			res.append("<tr><td>%-24s</td><td>%-7s</td>%s<td>%-16s</td><td>%-17s</td></tr>\n" % \
			(h, hosts[h].dispstate(), hosts[h].dispstats(),  hosts[h].addr, time.strftime("%Y-%m-%d %H:%M:%S", time.localtime(hosts[h].statetime))))
		res.append("</table>")
		res.append("<h4>Log of Events</h4>")
		for m in msgs[len(msgs)-30:]:
			res.append("%s<BR>" % m)
		res.append("</body></html>")
		return res

	def builderror(self, code, cause, lcause):
		res=[]
		res.append('<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML 2.0//EN">')
		res.append('<html><head>')
		res.append('<title>%s %s</title>' % (code, cause))
		res.append('</head><body>')
		res.append('<h1>%s</h1>' % (cause))
		res.append('<p>%s</p>' % lcause)
		res.append('<hr>')
		res.append('<address>hbd (Unix) Server at %s:%s</address>' % (hbd_host, hbd_port))
		res.append('</body></html>')
		return res
	

	def do_GET(self):
		global sig
		xsig = 0
		self.do_HEAD()
		headers=[]

		if DEBUG > 2: sys.stderr.write("handle\n")
		uri = self.path
		upar=string.split(uri,"?")
		if len(upar) == 1:
			uarg=[]
		else:
			uarg=string.split(upar[1],"&")

		if DEBUG > 2: sys.stderr.write("handle = %s\n" % (uri))
		code = 200
		cause = "OK"
		if uri == "/":
			res=self.buildpage()

		elif upar[0] == "/c":	# command on host /c?h=melschserver&c=sudo%20ls 
			uname=""
			ucmd=""
			if len(uarg) != 2 or len(uarg[0]) < 3 or len(uarg[1]) < 3:
				code=400
				cause='Argument error'
				res=self.builderror(code, cause, "need h= and c= arguments")
			else:
				if uarg[0][:2] == "h=":
					uname=uarg[0][2:]
				if uarg[1][:2] == "c=":
					ucmd=uarg[1][2:]
				if ucmd != "" and uname != "" and hosts.has_key(uname):
					hosts[uname].cmds.append(urllib.unquote(ucmd))
					res=self.buildhead()
					res.append("2Done")

		elif upar[0] == "/d":	# drop host  /d?h=melschserver
			if len(uarg) != 1 or len(uarg[0]) < 3:
				code=400
				cause='Argument error'
				res=self.builderror(code, cause, "need h= argument")	
			else:
				if uarg[0][:2] == "h=":
					uname=uarg[0][2:]
				if uname != "" and hosts.has_key(uname):
					del hosts[uname]
					log("%s dropped" % uname)
					res=self.buildhead()
					res.append("Done")
	
		elif upar[0] == "/n":   # register name
			if len(uarg) != 1 or len(uarg[0]) < 3:
				code=400
				cause='Argument error'
				res=self.builderror(code, cause, "need h= argument")	
			else:
				res=self.buildhead()
				if uarg[0][:2] == "h=":
					uname=uarg[0][2:]
				if uname != "" and hosts.has_key(uname):
					err = nsupdate(uname, hosts[uname].addr)
					ll="nsupdate request: %s" % err
				else:
					ll="name %s not found" % uname
				res.append(ll)
				log(ll)

		elif upar[0] == "/r":   # restart
			res=self.buildhead()
			res.append("restart request")
			xsig=signal.SIGHUP
			log("restart request")

		else:
			code=404
			cause="Not Found"
			res=self.builderror(code, cause, "The requested URL was not found on this server.")


		tosend = []
		for h in headers:
			tosend.append("%s\r" % h)
		tosend.append("\r")
#		self.request.send("HTTP/1.0 %s %s\r\n" % (code, cause))
#		for h in headers:
#			self.request.send("%s\r\n" % h)
#		self.request.send("\r\n")

		tosend += res
		self.wfile.write(string.join(tosend, "\n"))

		if xsig:
			sig = xsig

def setrunning(new):
	global running
	if DEBUG > 0: sys.stderr.write("running is now = %s\n" % (new))
	running = new


def closeup():
	setrunning(False)
	try:
		sock.close()
	except:
		pass
	try:
		sock6.close()
	except:
		pass
	if DEBUG > 0: sys.stderr.write("asking http server to stop\n")
	
	try:
		serv.shutdown()
		if DEBUG > 0: sys.stderr.write("http server stopped\n")
	except Exception as e:
		if DEBUG > 0: sys.stderr.write("http server did NOT stop: %s\n" % str(e))
	try:
		serv.server_close()
	except:
		pass

	log("restarting")
	try:
		logf.close()
	except:
		pass

#	signal.signal(signal.SIGTERM, 0)
	signal.signal(signal.SIGHUP, 0)


def restart():
	print "execv %s %s" % (sys.argv[0], [sys.argv[0]]+cmdargs)
	os.execv(sys.argv[0], [sys.argv[0]]+cmdargs)
	print "should not be here"

def saveandrestart():
	closeup()
	restart()


def pickleit():
	pickf = open(PICKFILE, 'w')
	pick = cPickle.Pickler(pickf)
	pick.dump(hosts)
	pick.dump(htab)
	pick.dump(msgs)
	pick.dump(lastfm)
	pickf.close()


#
# Main
#

helpflag = False
forground = False
optlist = []
args = []
home = os.environ['HOME']
cmdargs = []
configfile = "%s/.hbrc" % home

try:
	optlist, args = getopt.getopt(sys.argv[1:], 'c:dfh:vx')
except:
	helpflag = True

for o, a in optlist:
	if o == '-c':
		configfile = a
		cmdargs += [o, a]
	if o == '-f':
		forground = True
		cmdargs += [o]
	elif o == '-h':
		helpflag = True
	elif o == '-v':
		verbose = True
		cmdargs += [o]
	elif o == '-x':
		DEBUG += 1
		cmdargs += [o]

if helpflag:
	print "hbc HeartBeatDaemon"
	print "usage: hbd [-dfhvx] [-c configfile]"
	print
	print "	-c configfile"
	print "	-d display"
	print "	-f run in foreground"
	print "	-h this help"
	print "	-v verbose"
	print "	-x increase debug lvl"
	print
	print """ config file can contain
logfile = /var/log/heartbeat.log
logfmt = [text|msg]
hb_port = 50003
interval = 20
hbd_port = 50004
hbd_host = www.domain.com
grace = 2
"""

	sys.exit(1)

#
# set defaults

hb_port = PORT
hbd_host = THOST
hbd_port = TPORT
logfile = LOGFILE
logfmt = "text"
interval = INTERVAL
grace = GRACE
watchhosts = []
dyndnshosts = []
drophosts = []

try:
	f = open(configfile, "r")
	if verbose:
		print "notice: using config file %s" % configfile
except:
	print "warning: running without config file: %s" % configfile
	f = None

if f:
	while 1:
		l = f.readline()
		if len(l) == 0:
			break
		if verbose:
			print "  %s" % l[:-1]
		r = l[:-1].split('=')
		if r[0] == 'interval':
			interval = eval(r[1])
		elif r[0] == 'grace':
			grace = eval(r[1])
		elif r[0] == 'hbd_port':
			hbd_port = eval(r[1])
		elif r[0] == 'hbd_host':
			hbd_host = r[1]
		elif r[0] == 'hb_port':
			hb_port = eval(r[1])
		elif r[0] == 'logfile':
			logfile = r[1]
		elif r[0] == 'logfmt':
			logfmt = r[1]
		elif r[0] == 'watchhosts':
			watchhosts = eval(r[1])
		elif r[0] == 'dyndnshosts':
			dyndnshosts = eval(r[1])
		elif r[0] == 'drophosts':
			drophosts = eval(r[1])
	f.close()

if len(args) != 0:
	print "error: args"
	sys.exit(1)


if verbose:
	print "notice: logging to %s" % logfile
logf = initlog(logfile)

if os.path.exists(PICKFILE):
	pickf = open(PICKFILE, 'r')
	pick = cPickle.Unpickler(pickf)
	try:
		hosts = pick.load()
		htab = pick.load()
		msgs = pick.load()
		try:
			lastfm = pick.load()
		except:
			lastfm = ["","",""]
		pickf.close()
	except:
		os.unlink(PICKFILE)
	for h in hosts.keys():
		hosts[h].fixup()
	for h in drophosts:
		if h in hosts:		# was: hosts.has_key(h):
			del hosts[h]


now = time.time()
startsec = int(now) % interval


log("Starting %s" % VER)
atexit.register(on_exit)

ilist = []

sock = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
sock.bind(("", hb_port))
sock.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
ilist.append(sock)

sock6 = socket.socket(socket.AF_INET6, socket.SOCK_DGRAM)
sock6.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)
sock6.bind(("", hb_port))
ilist.append(sock6)


serv = HttpServer((hbd_host, hbd_port), HttpHandler)
servthread = threading.Thread(target=serv.serve_forever)
servthread.start()

#ilist.append(serv.fileno())

if not forground:
	pid = os.fork()
	if pid > 0:
		if verbose:
			print "daemoinizing... pid = %d" % pid
		sys.exit(0)

	verbose = False
	os.close(0)
	os.close(1)
	os.close(2)
	sys.stdin.close()
	sys.stdout = NullDevice()
	sys.stderr = NullDevice()
	os.chdir("/")
	os.setsid()
	os.umask(0)

running = True
sig = 0
#signal.signal(signal.SIGTERM, handler)
signal.signal(signal.SIGHUP, handler)

next = int(now)+15   # 15 seconds time to settle after (re-)start
sleep = 1
firstcheck = int(now) + 15

while running:
	sr = None
	if DEBUG > 2: sys.stderr.write("about to sleep = %s\n" % (sleep))
	try:
		sr = select.select(ilist, [], [], sleep)
		now = time.time()
	except KeyboardInterrupt:
		sys.stderr.write("Keyboard Interrupt!\n")
		running = False
		closeup()
		continue
	except select.error, value:
		if value[0] != 4:		# interrupted system call
			sys.stderr.write("select err %s %s" % (select.error, value))
			#raise os.error, value
			continue
		continue
	except Exception as e:
		if DEBUG > 2: sys.stderr.write("select exception %s\n" % (str(e)))
		sys.exit(1)
	if DEBUG > 2: sys.stderr.write("woke from sleep = %s (%s)\n" % (str(sr), str(ilist)))
	for fh in sr[0]:
		if fh in [sock, sock6]:
			readsock(fh)
#		elif fh == serv.fileno():
#			serv.handle_request()
		else:
			sys.stderr.write("what happend just now?\n")
	if DEBUG > 2: sys.stderr.write("done handling, running is %s, sig is %s\n" % (running, sig))

	# check hour/day/week 
	for v in xrange(3):
		fm=tsfm[v]
		ts=time.strftime(tsfm[v], time.localtime(now))
		if ts != lastfm[v]:
			lastfm[v]=ts
			for h in hosts.keys():
				hosts[h].hdwcounts[v] = [hosts[h].doesack, hosts[h].upcount]
	
	if now >= next and now >= firstcheck:
		next = now+1
		checkoverdue()

	sleep = next-now
	if sleep < 0:
		sys.stderr.write("sleep is negative! %s next = %s\n" % (sleep, next))
		sleep = 0
	if DEBUG > 2: sys.stderr.write("sleep = %s next = %s\n" % (sleep, next))

	if sig != 0:
		setrunning(False)



if sig == signal.SIGHUP:
	if DEBUG > 0: sys.stderr.write("signal 1 saveandrestart\n")
	saveandrestart()