<?php
//-------------------------------------------------
// This files show an example of how to get the 
// file uploaded information
// Requires:
//  - PHP > 5.3
//  - extension=php_fileinfo.dll
//  
//  Taken from: http://www.php.net/manual/es/features.file-upload.php#114004
//-------------------------------------------------

header('Content-Type: text/plain; charset=utf-8');

try {
    
    // Undefined | Multiple Files | $_FILES Corruption Attack
    // If this request falls under any of them, treat it invalid.
    if (
        !isset($_FILES['upfile']['error']) ||
        is_array($_FILES['upfile']['error'])
    ) {
        throw new RuntimeException('Invalid parameters.');
    }

    // Check $_FILES['upfile']['error'] value.
    switch ($_FILES['upfile']['error']) {
        case UPLOAD_ERR_OK:
            break;
        case UPLOAD_ERR_NO_FILE:
            throw new RuntimeException('No file sent.');
        case UPLOAD_ERR_INI_SIZE:
        case UPLOAD_ERR_FORM_SIZE:
            throw new RuntimeException('Exceeded filesize limit.');
        default:
            throw new RuntimeException('Unknown errors.');
    }

    // You should also check filesize here. 
    if ($_FILES['upfile']['size'] > 1000000) {
        throw new RuntimeException('Exceeded filesize limit.');
    }

    // DO NOT TRUST $_FILES['upfile']['mime'] VALUE !!
    // Check MIME Type by yourself.
    $finfo = new finfo(FILEINFO_MIME_TYPE);
    if (false === $ext = array_search(
        $finfo->file($_FILES['upfile']['tmp_name']),
        array(
            'jpg' => 'image/jpeg',
            'png' => 'image/png',
            'gif' => 'image/gif',
        ),
        true
    )) {
        throw new RuntimeException('Invalid file format.');
    }

    // You should name it uniquely.
    // DO NOT USE $_FILES['upfile']['name'] WITHOUT ANY VALIDATION !!
    // On this example, obtain safe unique name from its binary data.
    
    /* UNCOMMENT THIS CODE TO MOVE THE FILE TO ITS TARGET LOCATION

    if (!move_uploaded_file(
        $_FILES['upfile']['tmp_name'],
        sprintf('./uploads/%s.%s',
            sha1_file($_FILES['upfile']['tmp_name']),
            $ext
        )
    )) {
        throw new RuntimeException('Failed to move uploaded file.');
    }
    */

    echo 'File is uploaded successfully.'.PHP_EOL;
    echo $_FILES['upfile']['name'];

} catch (RuntimeException $e) {

    echo $e->getMessage();

}

?>