<?php
if (!array_key_exists("i", $_GET) || !is_numeric($_GET["i"]))
die("Index unspecified or non-numeric");
$index = (int) $_GET["i"];
$arch = RarArchive::open("example.rar");
if ($arch === FALSE)
die("Cannot open example.rar");
$entries = $arch->getEntries();
if ($entries === FALSE)
die("Cannot retrieve entries");
if (!array_key_exists($index, $entries))
die("No such index: $index");
$orfilename = $entries[$index]->getName(); //UTF-8 encoded
$filesize = $entries[$index]->getUnpackedSize();
/* you could check HTTP_IF_MODIFIED_SINCE here and compare with
* $entries[$index]->getFileTime(). You could also send a
* "Last modified" header */
$fp = $entries[$index]->getStream();
if ($fp === FALSE)
die("Cannot open file with index $index insided the archive.");
$arch->close(); //no longer needed; stream is independent
function detectUserAgent() {
if (!array_key_exists('HTTP_USER_AGENT', $_SERVER))
return "Other";
$uas = $_SERVER['HTTP_USER_AGENT'];
if (preg_match("@Opera/@", $uas))
return "Opera";
if (preg_match("@Firefox/@", $uas))
return "Firefox";
if (preg_match("@Chrome/@", $uas))
return "Chrome";
if (preg_match("@MSIE ([0-9.]+);@", $uas, $matches)) {
if (((float)$matches[1]) >= 7.0)
return "IE";
}
return "Other";
}
/*
* We have 3 options:
* - For FF and Opera, which support RFC 2231, use that format.
* - For IE and Chrome, use attwithfnrawpctenclong
* (http://greenbytes.de/tech/tc2231/#attwithfnrawpctenclong)
* - For the others, convert to ISO-8859-1, if possible
*/
$formatRFC2231 = 'Content-Disposition: attachment; filename*=UTF-8\'\'%s';
$formatDef = 'Content-Disposition: attachment; filename="%s"';
switch (detectUserAgent()) {
case "Opera":
case "Firefox":
$orfilename = rawurlencode($orfilename);
$format = $formatRFC2231;
break;
case "IE":
case "Chrome":
$orfilename = rawurlencode($orfilename);
$format = $formatDef;
break;
default:
if (function_exists('iconv'))
$orfilename =
@iconv("UTF-8", "ISO-8859-1//TRANSLIT", $orfilename);
$format = $formatDef;
}
header(sprintf($format, $orfilename));
//cannot send error messages from now on (headers already sent)
//replace by real content type, perhaps infering from the file extension
$contentType = "application/octet-stream";
header("Content-Type: $contentType");
header("Content-Transfer-Encoding: binary");
header("Content-Length: $filesize");
if ($_SERVER['REQUEST_METHOD'] == "HEAD")
die();
while (!feof($fp)) {
$s = @fread($fp, 8192);
if ($s === false)
break; //useless to send error messages
echo $s;
}
?>
