CKEditor file upload with wrong file encoding (not UTF-8)

I am using PHP 5.6 on Windows IIS. When creating a link and uploading a file for that link through ckeditor, file name on server is not with special characters like: ČĆŽŠĐ. Problem is only when uploading files through ckeditor. When uploading text to database, there is no problem with the encoding. How can I make ckeditor to maybe tell server the right encoding, maybe to include encoding i request, or whatever I need to do to make it work? This PHP encoding is a nightmare!

I've fixed it with this:

iconv("utf-8", "cp1250", $_FILES['upload']['name'])

But, is there no way I can tell PHP to just treat everything as UTF-8? I've tried setting every single setting regarding encoding and codepage in php.ini to UTF-8 and it did not help. It really seems inconsistent and finicky. Any PHP experts that can tell me the simple solution to this mess?

These are the upload headers:

POST https://nsdmup-a.hr/cms/news_fileupload.php?CKEditor=fullText&CKEditorFuncNum=1&langCode=en HTTP/1.1
Host: nsdmup-a.hr
Connection: keep-alive
Content-Length: 1069214
Cache-Control: max-age=0
Origin: https://nsdmup-a.hr
Upgrade-Insecure-Requests: 1
Content-Type: multipart/form-data; boundary=----WebKitFormBoundarysc0FA4jsjDe2Z4s8
User-Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/64.0.3282.186 Safari/537.36
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8
Referer: https://nsdmup-a.hr/cms/news_add.php?editId=293
Accept-Encoding: gzip, deflate, br
Accept-Language: hr-HR,hr;q=0.9,en-US;q=0.8,en;q=0.7,sr;q=0.6,bs;q=0.5,ja;q=0.4
Cookie: PHPSESSID=45iuc1r017sb75bte57dl0te71

------WebKitFormBoundarysc0FA4jsjDe2Z4s8
Content-Disposition: form-data; name="upload"; filename="511-D-022-2018. dopis ministru - zapšljavanje namještenika2.pdf"
Content-Type: application/pdf

This is the file name he wrote to disk: "511-D-022-2018. dopis ministru - zapĹˇljavanje namjeĹˇtenika2.pdf"

Solution

To my experience, this is a problem with Windows and all PHP versions up until v7.0

So, either you continue using iconv function or upgrade PHP to at least v7.1 (changelog regarding Windows)

You can also create a helper function with contents like this:

if (version_compare(phpversion(), '7.1.0', '<') and strtoupper(substr(php_uname('s'), 0, 3)) === 'WIN')
{
    // Windows and PHP 7.0 or less. Use iconv
    return iconv('utf-8', 'cp1250', $filename);
}
else
{
    // Should be all good
    return $filename;
}