Code:
<?php
    /*
    Silentum Uploader v1.4.0
    Modified March 6, 2008
    uploader.php copyright 2005-2008 "HyperSilence"
    */

    // Begin options

    $allow_file_deletion = true; // To allow visitors to delete files, leave this at true; otherwise, change it to false

    $file_extensions = array(".doc", ".gif", ".htm", ".html", ".jpg", ".png", ".txt"); // Add or delete the file extensions you want to allow

    $file_extensions_list = ".doc, .gif, .htm, .html, .jpg, .png, .txt"; // Type the same as above, without the quotes separating them

    $max_length = 30; // The maximum character length for a file name

    $maximum_file_size = "51200"; // In bytes

    $upload_log_file = "upload_log.txt"; // Change this to the log file you want to use

    // End options
    // If you're using a different folder name for uploaded files other than "files", change both occurrences of "files" on lines 29 and 30 below

    $folder_directory = "http://".$_SERVER["HTTP_HOST"].dirname($_SERVER["PHP_SELF"]);
    $message = "";
    $set_chmod = 0;
    $site_uri = "http://".$_SERVER["HTTP_HOST"].$_SERVER["PHP_SELF"];
    $upload_directory = "primljene_slike/";
    $upload_uri = $folder_directory."/primljene_slike/";
    
    $folder_name_length = strlen($upload_directory);

    if($allow_file_deletion == true) $status = "enabled";
    else $status = "disabled";

    if($_REQUEST["delete"] && $allow_file_deletion) {
    $resource = fopen($upload_log_file,"a");
    fwrite($resource,date("F d, Y / h:i:sa")." - ".$_REQUEST["delete"]." deleted by ".$_SERVER["REMOTE_ADDR"]."\n");
    fclose($resource);

    if(strpos($_REQUEST["delete"],"/.") > 0);
    elseif(strpos($_REQUEST["delete"],$upload_directory) === false);    
    elseif(substr($_REQUEST["delete"],0,$folder_name_length) == $upload_directory) {
    unlink($_REQUEST["delete"]);
    $message = "File has been deleted.";
    header("Location: $site_uri?message=$message");
    }
    }

    elseif($_FILES["userfile"]) {
    $resource = fopen($upload_log_file,"a");
    fwrite($resource,date("F d, Y / h:i:sa")." - ".$_FILES["userfile"]["name"]." "
    .$_FILES["userfile"]["type"]." uploaded by ".$_SERVER["REMOTE_ADDR"]."\n");
    fclose($resource);

    $file_type = $_FILES["userfile"]["type"]; 
    $file_name = $_FILES["userfile"]["name"];
    $file_ext = strtolower(substr($file_name,strrpos($file_name,".")));
    @chmod($upload_uri."".$file_name, 0755);
    if($_FILES["userfile"]["size"] > $maximum_file_size) {
    $message = "ERROR: File size cannot be over ".$maximum_file_size." bytes.";
    }

    elseif($file_name == "") $message = "ERROR: Please select a file to upload.";
    elseif(strlen($file_name) > $max_length) $message = "ERROR: The maximum length for a file name is ".$max_length." characters.";
    elseif(!preg_match("/^[A-Z0-9_.\- ]+$/i",$file_name)) $message = "ERROR: Your file name contains invalid characters.";
    elseif(!in_array($file_ext, $file_extensions)) $message = "ERROR: <ins>$file_ext</ins> is not an allowed file extension.";
    else $message = upload_file($upload_directory, $upload_uri);
    header("Location: $site_uri?message=$message");
    }

    elseif(!$_FILES["userfile"]);
    else $message = "ERROR: Invalid file specified.";

    $open = opendir($upload_directory);
    $uploaded_files = "";
    while($file = readdir($open)) {
    if(!is_dir($file) && !is_link($file)) {
    $uploaded_files .= "        <tr>
                <td style=\"background: #fff; color: #000; text-align: left; width: 70%\"><a href=\"$upload_directory$file\" title=\"$file (".filesize($upload_directory.$file)." bytes)\">".$file."</a> (".filesize($upload_directory.$file)." bytes)</td>";
    if($allow_file_deletion)
    $uploaded_files .= "
                <td style=\"background: #fff; color: #000; text-align: right; width: 30%\"><a href=\"?delete=$upload_directory".urlencode($file)."\" title=\"Delete File\">Delete File</a></td>";
    else
    $uploaded_files .= "
                <td style=\"background: #fff; color: #000; text-align: right; width: 30%\"><del><strong>Delete File</strong></del></td>";
    $uploaded_files .= "
            </tr>
            <tr>
                <td colspan=\"2\" style=\"background: #eee; color: #000; text-align: left; text-indent: 20px\">Uploaded <strong>".date("F d, Y / h:ia", filemtime($upload_directory.$file))."</strong></td>";
    $uploaded_files .="
            </tr>
    ";
    }
    }

    function upload_file($upload_directory, $upload_uri) {
    $file_name = $_FILES["userfile"]["name"];
    $file_name = str_replace(" ","_",$file_name);
    $file_path = $upload_directory.$file_name;
    $temporary = $_FILES["userfile"]["tmp_name"];

    $result = move_uploaded_file($temporary, $file_path);
    if(!chmod($file_path,0777))
    $message = "ERROR: A folder to place the files was not found, or the files need to be CHMODed to 777.";
    else $message = ($result)?"File has been uploaded." : "An error has occurred.";
    return $message;
    }
?>