cloudflare.php

<?php
/*
Plugin Name: Cloudflare
Plugin URI: https://blog.cloudflare.com/new-wordpress-plugin/
Description: Cloudflare speeds up and protects your WordPress site.
Version: 3.3.2
Author: John Wineman, Furkan Yilmaz, Junade Ali (Cloudflare Team)
License: BSD-3-Clause
*/

// To enable HTTP2 Server Push feature, add the following line to wp-config.php file
// define('CLOUDFLARE_HTTP2_SERVER_PUSH_ACTIVE', true);

// Exit if accessed directly
if (!defined('ABSPATH')) {
    exit;
}

define('CLOUDFLARE_MIN_PHP_VERSION', '5.3.10');
define('CLOUDFLARE_MIN_WP_VERSION', '3.4');
define('CLOUDFLARE_PLUGIN_DIR', plugin_dir_path(__FILE__));

// PHP version check has to go here because the below code uses namespaces
if (version_compare(PHP_VERSION, CLOUDFLARE_MIN_PHP_VERSION, '<')) {
    // We need to load "plugin.php" manually to call "deactivate_plugins"
    require_once ABSPATH.'wp-admin/includes/plugin.php';

    deactivate_plugins(plugin_basename(__FILE__), true);
    wp_die('<p>The Cloudflare plugin requires a PHP version of at least '.CLOUDFLARE_MIN_PHP_VERSION.'; you have '.PHP_VERSION.'.</p>', 'Plugin Activation Error', array('response' => 200, 'back_link' => true));
}

// Plugin uses namespaces. To support old PHP version which doesn't support
// namespaces we load everything in "cloudflare.loader.php"
require_once CLOUDFLARE_PLUGIN_DIR.'cloudflare.loader.php';