Form boundaries and writing php://input to a file in php - php

Question

So I want users to be able to upload big files without having to worry about the post max size values.
The alternative is using PUT and send a file as raw data.
When using jquery I can do this:
var data = new FormData();
jQuery.each($('#file_upload')[0].files, function(i, file) {
data.append('file-'+i, file);
});
$.ajax({
url: 'upload.php?filename=test.pdf',
data: data,
cache: false,
contentType: false,
processData: false,
type: 'PUT',
});
In PHP I can do this:
$f = fopen($_GET['filename'], "w");
$s = fopen("php://input", "r");
while($kb = fread($s, 1024))
{
fwrite($f, $kb, 1024);
}
fclose($f);
fclose($s);
Header("HTTP/1.1 201 Created");
I am not doing:
$client_data = file_get_contents("php://input");
Since putting the whole file into a variable will surely fill up all memory when uploading huge files.
The thing I cannot figure out is how to write the file data without the form boundaries.
Right now it writes at the top of the file something like this:
------WebKitFormBoundaryVz0ZGHLGxBOCUVQG
Content-Disposition: form-data; name="file-0"; filename="somename.pdf"
Content-Type: application/pdf
and at the bottom something like this:
------WebKitFormBoundaryVz0ZGHLGxBOCUVQG--
So I need to parse the data. But for that I need to read the whole data stream into memory and with large video files I don't want to do that.
I did read something about maybe creating a php://temp stream. But no luck yet with that.
How can I write just the content to a file, without the boundary header? And without first pumping all the data into a variable?

Answer 1

Maybe a combination of fgets to stop reading at a newline and checking for the boundaries:
while($kb = fgets($s, 1024))
{
if(strpos($kb, '------') === false) //or !== 0 for first position
{
fwrite($f, $kb, 1024);
}
}

Answer 2

You can use this (there are many like it). It supports chunked uploads which means you won't hit any post/file max sizes as long as each upload chunk is less than the post max size.
It also includes the PHP code you would need on the server side.

Answer 3

There is no need to recreate the wheel. Just use POST and change PHP's config to bigger limits. Those limits can also be set on a per directory / host basis.
Using .htaccess or your apache.conf
php_value upload_max_filesize 10G
php_value post_max_size 10G
It is also a good idea to adjust other limits, like max_input_time.
Don't forget to relocated the received file using move_uploaded_file to avoid any extra work.