Reading filenames from a zip file inside another zip file - php

Question

I am trying to get all filenames from the files inside a zip file. It all works perfectly until the zip file contains another zip file and I try to get the included file names from the included zip as well.
I want to get all included filenames without extracting the file.
For some reason it always refuses to open the included zip file, as if it does not recognie it as a zip file.
To make 100% sure it is a zip for testing I simply included the same zip inside the main zip.
While it properly reads the main zipfile it returns false if I want to read the included file.
I have been trying to get this script to work for 3 days now but I keep failing so I decided to see if someone here can help me out with this.
This is the script I am using to read a zipfile contents:
function firstzipper($file) {
global $filesroot, $pagefile;
$zipinc = new ZipArchive();
if ($zipinc->open($file) === TRUE) {
for ($i = 0; $i < $zipinc->numFiles; $i++) {
$filename_full = $zipinc->getNameIndex($i);
$filename = substr($filename_full, strrpos($filename_full, '/') + 1);
if (!is_dir($filename)) {
$filename = filter_var($filename, FILTER_SANITIZE_STRING);
$ext = pathinfo($filename, PATHINFO_EXTENSION);
if ($ext == 'zip') {
secondzipper($filesroot.$pagefile.'/'.$filename_full);
}
}
array_push($inc_files_arr,$filename);
}
return $inc_files_arr;
}
}
firstzipper($filesroot.$url);
secondzipper inside the function above is simply the same function, copied and renamed.
The zipfile looks like this:
E:/myfolder/fileserver/temper.zip/myincluded.zip
The function opens temper.zip but returns false on myincluded.zip.
I hope I have included all info needed, if not let me know and I add what else is required.