百词斩zpk文件研究分析

public function zpk_parser() {

        $res_path   = ROOT_PATH . "public/zpk/";
        $file_lists = glob($res_path . "*.zpk");
        foreach ($file_lists as $file_path) {

            $dir_name = explode(".zpk", $file_path)[0];
            if (!is_dir($dir_name)) {
                mkdir($dir_name, "0777");
            }
            $zpk  = file_get_contents($file_path);
            $bin  = bin2hex($zpk);
            $json = [
                "head" => "7b22",
                "end"  => "227d"
            ];
            $jpg  = [
                "head" => "ffd8ff",
                "end"  => "ffd9"
            ];
            $jpeg = [
                "head" => "ffd8ff",
                "end"  => "ffd9"
            ];
            $gif  = [
                "head" => "474946383961",
                "end"  => ""
            ];
            $png  = [
                "head" => "89504e470d0a1a0a",
                "end"  => "0000000049454e44ae426082"
            ];

            /**
             * 读取文件列表
             */
            preg_match_all("/6d6574612e6a736f6e(.*)/", $bin, $matches_lists);
            $matches_lists
                     = array_map(function ($v) { return hex2bin($v); }, array_filter(explode("0a", $matches_lists[0][0])));
            //根据文件位置确定标识
            $mp3  = [
                "head" => $json["end"],
                "end"  => $jpg["head"]
            ];
            $aac  = [
                "head" => $jpg["end"],
                "end"  => $png["head"]
            ];

            $message = var_export($matches_lists, true) . "\r\n";
            $flag    = true;
            foreach ($matches_lists as $v) {
                //遍历文件列表,从流中读取内容并生成相应文件
                $file_name = $v;
                $file_type = explode(".", $v)[1];

                //跳过gif图片
                if ($file_type == "gif") continue;

                $head = $$file_type["head"];
                $end  = $$file_type["end"];
                preg_match_all("/{$head}(.*?){$end}/i", $bin, $matches);
                $message .= $file_type . ":";
                if (!empty($matches[0][0])) {
                    if (strlen($matches[0][0]) % 2 == 0) {
                        file_put_contents($dir_name . DS . $file_name, hex2bin($matches[0][0]));
                        $message .= "生成成功" . "\r\n";
                    } else {
                        $message .= "数据错误\r\n";
                        $flag    = false;
                    }
                } else {
                    $message .= "没有匹配到数据";
                }
            }
            file_put_contents($dir_name . DS . ($flag ? "true.log" : "false.log"), $message, FILE_APPEND);
            echo $file_path . "\r\n";
        }
    }