index.php

<?php
header("Content-Type: text/text");
 
############################################################################
#    Simple PHP Upload Script for ShareX v0.1
#    Copyright (C) 2013  Richard Cornwell
#    Website: http://thegeekoftheworld.com/
#    Script:  http://thegeekoftheworld.com/using-a-php-upload-script-for-sharex/
#    Email:   richard@techtoknow.net
#
#    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 3 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, see <http://www.gnu.org/licenses>.
############################################################################



function get_link()
{
	#Change this to change how long a link you want to generate.
	$length_of_link = 5;
	$link = "";
	$works = false;
	while (!$works)
	{
		$link = substr(base64_encode(md5(rand())),0,$length_of_link);
		if (empty(glob(getcwd() . "/" . $link . ".*")))
		{
			$works = true;
		}
	}
	return $link;
}

$key = "CHANGEME";
$uploadhost = "http://upload.domain.tld/";
$redirect = "http://domain.tld/";
 
#Comment this next line if you want Robots to index this site.
if ($_SERVER["REQUEST_URI"] == "/robot.txt") { die("User-agent: *\nDisallow: /"); }

#Don't edit past this point!
if (isset($_POST['k'])) {
    if ($_POST['k'] == $key) {
		$link = get_link();
		$target = getcwd() . "/" . $link . "." . strtolower(end(explode(".", $_FILES["d"]["name"])));
        if (move_uploaded_file($_FILES['d']['tmp_name'], $target)) {
            echo $uploadhost . $link . "." . end(explode(".", $_FILES["d"]["name"]));
        } else {
            echo "Sorry, there was a problem uploading your file.";
        }
    } else {
        header('Location: '.$redirect);
    }
} else {
    header('Location: '.$redirect);
}
?>