Zip-> close（）返回false，尽管检查

Question

I'm trying to create a zip file with the ZipArchive class. I was reading a lot here and there and implemented a lot of checks (file existence, directory writable..). But zip->close() still returns 'false' and I can't figure out why.

if (!is_writable('../temp_downloads/')) { 
    die('directory not writable'); }

function create_zip($files = array(),$destination = '',$overwrite = false) {
    $destination = "../temp_downloads/".$destination.".zip";
    if(file_exists($destination) && !$overwrite) { return false; }
        $valid_files = array();

        if(is_array($files)) {
            foreach($files as $file) {
            if(file_exists('../data/'.$file) && is_readable('../data/'.$file)) {
                $valid_files[] = $file;
            }
        }
    }

    if(count($valid_files)) {
        $zip = new ZipArchive();
        if($zip->open($destination,$overwrite ? ZIPARCHIVE::OVERWRITE : ZIPARCHIVE::CREATE) !== true) {
            exit('cannot create zip');
        }

        foreach($valid_files as $file) {
            $zip->addFile($file,$file); // result returns 'true'
        }

        $res = $zip->close(); //$res contains 'false'

        if(file_exists($destination)){
            error_log("zip exists ".$destination);
            header("Content-type: application/zip"); 
            header("Content-Disposition: attachment; filename=$destination");
            header("Content-length: " . filesize($destination));
            header("Pragma: no-cache"); 
            header("Expires: 0"); 
            readfile("$destination");
        } else {
            error_log("ERROR: Zip doesnt exist at ".$destination);
        }

        return file_exists($destination);
    } else {    
        return false;
    }
}

I call this function with

create_zip($files, 'PREFIX_'.$stamp, true);

where $files is an array and $stamp just a timestamp. For testing the destination folders chmod is set to 777

Could you help me?

Answer 1

You're (maybe?) using incorrect paths for your files in the zip operations:

Here you look for ../data/$file :

if(file_exists('../data/'.$file) && is_readable('../data/'.$file)) {
    $valid_files[] = $file;

But at zipping time, you have just:

$zip->addFile($file,$file);

instead of

$zip->addFile("../data/$file",$file);

I don't see how addFile could return true, unless you coincidentally happen to have duplicates of all those files in the script's current working directory, or you ARE working in a data directory and ../data is the same as .