}
$files = array("bui" => "bui", "default" => "bui-default", "imageview" => "imageview");
$log = './download/count.json';
if (!empty($files[$file_id])) {
    $url = "https://git.oschina.net/bui/" . $files[$file_id] . "/repository/archive?ref=master";
    addCount($log, $file_id);
    Header("HTTP/1.1 303 See Other");
    Header("Location: {$url}");
    exit;
}
$file_dir = $file_dir . "/";
if (!file_exists($file_dir . $file_name)) {
    //检查文件是否存在
    header("Content-Type: text/html; charset=utf-8");
    echo $file_dir . $file_name;
    echo "文件找不到";
    exit;
} else {
    addCount($log, $file_id);
    $file = fopen($file_dir . $file_name, "r");
    // 打开文件
    // 输入文件标签
    Header("Content-type: application/octet-stream");
    Header("Accept-Ranges: bytes");
    Header("Accept-Length: " . filesize($file_dir . $file_name));
    Header("Content-Disposition: attachment; filename=" . $file_name);
    // 输出文件内容
    echo fread($file, filesize($file_dir . $file_name));
    fclose($file);
    exit;
}
<?php

include "./count.php";
?>

<?php 
$count = getCount("./count.json", "a");
echo $count;
addCount("./count.json", "b");
echo getCount("count.json", "b");