#!/bin/bash



  #
  # Copyright (C) 2010 Cloud.com, Inc.  All rights reserved.
  # 
  # This software is licensed under the GNU General Public License v3 or later.
  # 
  # It 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 3 of the License, or 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, see <http://www.gnu.org/licenses/>.
  #
 


# save previous state
  mv /etc/haproxy/haproxy.cfg /etc/haproxy/haproxy.cfg.old
  mv /var/run/haproxy.pid /var/run/haproxy.pid.old

  mv /etc/haproxy/haproxy.cfg.new /etc/haproxy/haproxy.cfg
  kill -TTOU $(cat /var/run/haproxy.pid.old)
  sleep 2
  if haproxy -D -p /var/run/haproxy.pid -f /etc/haproxy/haproxy.cfg; then
    echo "New haproxy instance successfully loaded, stopping previous one."
    kill -KILL $(cat /var/run/haproxy.pid.old)
    rm -f /var/run/haproxy.pid.old
    exit 0
  else
    echo "New instance failed to start, resuming previous one."
    kill -TTIN $(cat /var/run/haproxy.pid.old)
    rm -f /var/run/haproxy.pid
    mv /var/run/haproxy.pid.old /var/run/haproxy.pid
    mv /etc/haproxy/haproxy.cfg /etc/haproxy/haproxy.cfg.new
    mv /etc/haproxy/haproxy.cfg.old /etc/haproxy/haproxy.cfg
    exit 1
  fi