Simple download counter in PHP

.htaccess

RewriteEngine On

RedirectMatch ^.*\.(zip|rar|pdf)$ /download.php?file=$0

download.php

<?php
	/*
	 *	Creato da/Made by Pier Riccardo Monzo, IslandOfCode.it
	 *	L'uso è libero, una citazione è apprezzata.
	 *	Free to use, a mention is appreciated.
	 */

	/***** FUNZIONI DI SUPPORTO */
	function getRealIPAddr(){
       if (!empty($_SERVER['HTTP_CLIENT_IP'])) {
           $ip=$_SERVER['HTTP_CLIENT_IP'];
       } elseif (!empty($_SERVER['HTTP_X_FORWARDED_FOR'])){
			$ip=$_SERVER['HTTP_X_FORWARDED_FOR'];
       }else{
			$ip=$_SERVER['REMOTE_ADDR'];
       }
	   return $ip;
	}
	
	/***** IMPOSTAZIONI E VARIABILI */
	date_default_timezone_set("Europe/Rome");
	
	$DB_FILE_COUNTER = 'counter.sqlite';
	$path = '/web/htdocs/www.example.it/home';

	/***** CONTROLLO PARAMETRI GET */
	if(!array_key_exists("file",$_GET)){
		die('FILE NON SPECIFICATO!');
	}

	/***** RECUPERO E RIELABORAZIONE PARAMETRO GET */
	$baseFileName = $_GET['file'];
	$file = $path.$_GET['file'];
	
	$quoted = sprintf('"%s"', addcslashes(basename($file), '"\\'));

	/***** INIT DATABASE E VARIABILI VARIE */
	$db = new SQLite3($DB_FILE_COUNTER, SQLITE3_OPEN_CREATE | SQLITE3_OPEN_READWRITE);
	$remoteIP = getRealIPAddr();
	$today = date("Y-m-d", time());

	/***** RICERCA POSSIBILE ENTRY PRE-ESISTENTE */
	$stm = $db->prepare('SELECT * FROM DOWNCOUNTER WHERE IP = ? AND DATE = ? AND FILENAME = ?');
	$stm->bindValue(1,$remoteIP);
	$stm->bindValue(2,$today);
	$stm->bindValue(3,$baseFileName);
	$rs = $stm->execute();
	
	$frs = $rs->fetchArray(SQLITE3_ASSOC);

	// Se questa combinazione di IP/DATA/NOME FILE esiste, bisogna solo aggiornare il numero di download
	if(!empty($frs)){

		$stm = $db->prepare('UPDATE DOWNCOUNTER SET HIT = ? WHERE IP = ? AND DATE = ? AND FILENAME = ?');
		$stm->bindValue(1,intval($frs['HIT'])+1);
		$stm->bindValue(2,$remoteIP);
		$stm->bindValue(3,$today);
		$stm->bindValue(4,$baseFileName);
		
		$stm->execute();
	} else {
		//Questo IP sta scaricando questo FILE per la prima volta OGGI, inserisci nuova ENTRY nella tabella
		
		$stm = $db->prepare('INSERT INTO DOWNCOUNTER(IP,DATE,FILENAME) VALUES(?,?,?)');
		$stm->bindValue(1,$remoteIP);
		$stm->bindValue(2,$today);
		$stm->bindValue(3,$baseFileName);
		//HIT è 1 di default
		$stm->execute();
	}

	/***** CREAZIONE HEADER PER LA RISPOSTA	 */
	$size   = filesize($file);

	header('Content-Description: File Transfer');
	header('Content-Type: application/octet-stream');
	header('Content-Disposition: attachment; filename=' . $quoted); 
	header('Content-Transfer-Encoding: binary');
	header('Connection: Keep-Alive');
	header('Expires: 0');
	header('Cache-Control: must-revalidate, post-check=0, pre-check=0');
	header('Pragma: public');
	header('Content-Length: ' . $size);
	
	/***** LETTURA FILE PER IL DOWNLOAD */
	ob_clean();
	flush();
	readfile($file);
	exit;
?>

table.sql

CREATE TABLE "DOWNCOUNTER" (
	"IP"	TEXT NOT NULL,
	"DATE"	TEXT NOT NULL,
	"FILENAME"	TEXT NOT NULL,
	"HIT"	INTEGER NOT NULL DEFAULT 1,
	PRIMARY KEY("IP","DATE","FILENAME")
)