public static async Task CompressAsync(byte[] byteIn, Stream outStream)
{
using var stream = new ZlibStream(new MemoryStream(), CompressionMode.Compress, CompressionLevel.BestCompression);
await stream.WriteAsync(byteIn, 0, byteIn.Length);
await stream.CopyToAsync(outStream);
}
public static async Task CompressAsync(Stream inputStream, Stream outputStream)
{
await using var stream = new ZlibStream(inputStream, CompressionMode.Compress, CompressionLevel.BestCompression);
await stream.CopyToAsync(outputStream);
}
static async Task ExtractSsf(FileInfo file, DirectoryInfo directory)
{
if (!file.Exists)
{
throw new FileNotFoundException(); // 找不到文件
}
var buffer = new byte[1024]; // 准备一个buffer
await using var fs = file.OpenRead(); // 打开文件
await fs.ReadAsync(buffer, 0, 4); // 先读它四个字节
switch (Encoding.ASCII.GetString(buffer, 0, 4))
{
case "Skin": // 是加密的包
{ // using语句不能直接在switch语句中使用
await using var data = new MemoryStream();
{
fs.Seek(4, SeekOrigin.Current); // 跳过四个字节
await using var decrypted_ssfbin = new CryptoStream(fs, SsfAES.CreateDecryptor(), CryptoStreamMode.Read); // AES解码流
// 这个流不能Seek, 得想办法把它变成能Seek的流
await decrypted_ssfbin.ReadAsync(buffer, 0, 4); // 跳过四个字节, 这个流不能Seek 所以用读取4个字节的方式跳过
await using var tmps = new ZlibStream(decrypted_ssfbin, Ionic.Zlib.CompressionMode.Decompress); // 创建解压缩流解压缩文件
await tmps.CopyToAsync(data); // 把流中所有内容复制到可以Seek的流
data.Seek(0, SeekOrigin.Begin); // Seek! 设置指针在流开始的位置
}
await data.ReadAsync(buffer, 0, 8); // 读取8个字节(两个uint)
//var size = BitConverter.ToUInt32(buffer.ToArray(), 0);// 整体大小
uint[] offsets;
{
var offsets_length = BitConverter.ToInt32(buffer.ToArray(), 4); // 偏移信息长度
offsets = new uint[offsets_length / 4]; // 初始化偏移信息数组(一个uint长4byte)
await data.ReadAsync(buffer, 0, offsets_length); // 将所有偏移信息一次读出来
for (int i = 0; i < offsets_length / 4; i++) // 计次循环
{
offsets[i] = BitConverter.ToUInt32(buffer.ToArray(), i * 4); // 一个一个转换
}
}
directory.Refresh();
if (!directory.Exists) // 检查目录是否存在
{
directory.Create(); // 不存在就创建一个
}
foreach (var offset in offsets) // 遍历偏移数组
{
data.Seek(offset, SeekOrigin.Begin); // Seek到偏移位置
string filename; // 文件名
{
await data.ReadAsync(buffer, 0, 4); // 读取文件长度
var name_len = BitConverter.ToInt32(buffer.ToArray(), 0);
if (buffer.Length < name_len) // 防止buffer小了塞冒出来
{
buffer = new byte[name_len];
}
await data.ReadAsync(buffer, 0, name_len);
filename = Encoding.Unicode.GetString(buffer.ToArray(), 0, name_len); // 文件名是Unicode编码的
}
await data.ReadAsync(buffer, 0, 4); // 读取内容长度
var content_len = BitConverter.ToInt32(buffer.ToArray(), 0);
if (buffer.Length < content_len) // 防止buffer小了塞冒出来
{
buffer = new byte[content_len];
}
await data.ReadAsync(buffer, 0, content_len); // 这里读取的就是内容了
await using var outfs = new FileInfo(Path.Combine(directory.FullName, filename)).OpenWrite();
await outfs.WriteAsync(buffer, 0, content_len); // 写入数据
await outfs.FlushAsync(); // 流用完记得冲
}
}
break;
case "\x50\x4b\x03\x04": // 这玩意是ZIP压缩包
ZipFile.ExtractToDirectory(file.FullName, directory.FullName); // 直接解压
break;
default: // 是不认识的文件呢
throw new NotSupportedException();
}
}
