GARbro-mirror/ArcFormats/NitroPlus/ArcSteinsGate.cs

340 lines
12 KiB
C#

//! \file ArcSteinsGate.cs
//! \date Thu Jul 24 23:36:01 2014
//! \brief Nitro+ Steins;Gate archive implementation.
//
// Copyright (C) 2014 by morkt
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to
// deal in the Software without restriction, including without limitation the
// rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
// sell copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
// IN THE SOFTWARE.
//
using System.IO;
using System.Text;
using System.Linq;
using System.Collections.Generic;
using System.ComponentModel.Composition;
using GameRes.Formats.Strings;
using GameRes.Utility;
namespace GameRes.Formats
{
public class SteinsGateOptions : ResourceOptions
{
public Encoding FileNameEncoding { get; set; }
}
[Export(typeof(ArchiveFormat))]
public class NpaSteinsGateOpener : ArchiveFormat
{
public override string Tag { get { return "NPA-SG"; } }
public override string Description { get { return arcStrings.NPASteinsGateDescription; } }
public override uint Signature { get { return 0; } }
public override bool IsHierarchic { get { return true; } }
public override bool CanWrite { get { return true; } }
public NpaSteinsGateOpener ()
{
Extensions = new string[] { "npa" };
}
internal static readonly byte[] KeyString = {
'B'^0xff, 'U'^0xff, 'C'^0xff, 'K'^0xff,
'T'^0xff, 'I'^0xff, 'C'^0xff, 'K'^0xff
};
public override ArcFile TryOpen (ArcView file)
{
int index_size = file.View.ReadInt32 (0);
if (index_size < 0x14 || index_size >= file.MaxOffset || index_size > 0xffffff)
return null;
var stream = new SteinsGateEncryptedStream (file, 4, (uint)index_size);
using (var header = new BinaryReader (stream))
{
int entry_count = header.ReadInt32();
if (!IsSaneCount (entry_count))
return null;
index_size -= 4;
int average_entry_size = index_size / entry_count;
if (average_entry_size < 0x11)
return null;
var dir = new List<Entry> (entry_count);
for (int i = 0; i < entry_count; ++i)
{
int name_length = header.ReadInt32();
if (name_length+0x10 > index_size)
return null;
byte[] name_raw = header.ReadBytes (name_length);
Encoding enc = GuessEncoding (name_raw);
string filename = enc.GetString (name_raw);
var entry = FormatCatalog.Instance.Create<Entry> (filename);
entry.Size = header.ReadUInt32();
entry.Offset = header.ReadInt64();
if (!entry.CheckPlacement (file.MaxOffset))
return null;
dir.Add (entry);
index_size -= name_length+0x10;
}
return new ArcFile (file, this, dir);
}
}
public override Stream OpenEntry (ArcFile arc, Entry entry)
{
return new SteinsGateEncryptedStream (arc.File, entry.Offset, entry.Size);
}
internal void Encrypt (byte[] buffer, int offset, int count)
{
for (int i = 0; i < count; ++i)
{
buffer[offset+i] ^= KeyString[i & 7];
}
}
Encoding GuessEncoding (byte[] text)
{
bool has_zero = false;
bool has_non_ascii = false;
foreach (var symbol in text)
{
if (0 == symbol)
{
has_zero = true;
break;
}
else if (symbol > 0x7f)
{
has_non_ascii = true;
}
}
if (has_zero)
return Encoding.Unicode;
else if (has_non_ascii)
return Encodings.cp932;
else
return Encoding.ASCII;
}
public override ResourceOptions GetDefaultOptions ()
{
return new SteinsGateOptions {
FileNameEncoding = GetEncoding (Properties.Settings.Default.SGFileNameEncoding),
};
}
public override object GetCreationWidget ()
{
return new GUI.CreateSGWidget();
}
Encoding GetEncoding (string name)
{
if ("shift-jis" == name)
return Encodings.cp932;
if ("utf-16" == name)
return Encoding.Unicode;
return Encoding.Default;
}
internal class RawEntry : Entry
{
public byte[] IndexName;
}
public override void Create (Stream output, IEnumerable<Entry> list, ResourceOptions options,
EntryCallback callback)
{
var sg_options = GetOptions<SteinsGateOptions> (options);
Encoding encoding = sg_options.FileNameEncoding.WithFatalFallback();
long start_pos = output.Position;
int callback_count = 0;
uint index_size = 4;
var real_entry_list = new List<RawEntry> (list.Count());
var used_names = new HashSet<string>();
foreach (var entry in list)
{
string name = entry.Name.Replace (@"\", "/");
if (!used_names.Add (name)) // duplicate name
continue;
var header_entry = new RawEntry { Name = entry.Name };
try
{
header_entry.IndexName = encoding.GetBytes (name);
}
catch (EncoderFallbackException X)
{
throw new InvalidFileName (entry.Name, arcStrings.MsgIllegalCharacters, X);
}
index_size += (uint)header_entry.IndexName.Length + 16;
real_entry_list.Add (header_entry);
}
output.Seek (4+index_size, SeekOrigin.Current);
foreach (var entry in real_entry_list)
{
using (var input = File.Open (entry.Name, FileMode.Open, FileAccess.Read))
{
var file_size = input.Length;
if (file_size > uint.MaxValue)
throw new FileSizeException();
entry.Offset = output.Position;
entry.Size = (uint)file_size;
if (null != callback)
callback (callback_count++, entry, arcStrings.MsgAddingFile);
using (var stream = new SteinsGateEncryptedStream (output))
input.CopyTo (stream);
}
}
if (null != callback)
callback (callback_count++, null, arcStrings.MsgWritingIndex);
output.Position = start_pos;
output.WriteByte ((byte)(index_size & 0xff));
output.WriteByte ((byte)((index_size >> 8) & 0xff));
output.WriteByte ((byte)((index_size >> 16) & 0xff));
output.WriteByte ((byte)((index_size >> 24) & 0xff));
var encrypted_stream = new SteinsGateEncryptedStream (output);
using (var header = new BinaryWriter (encrypted_stream))
{
header.Write (real_entry_list.Count);
foreach (var entry in real_entry_list)
{
header.Write (entry.IndexName.Length);
header.Write (entry.IndexName);
header.Write ((uint)entry.Size);
header.Write ((long)entry.Offset);
}
}
}
}
public class SteinsGateEncryptedStream : Stream
{
private Stream m_stream;
private long m_base_pos;
private bool m_should_dispose;
public Stream BaseStream { get { return m_stream; } }
public override bool CanRead { get { return m_stream.CanRead; } }
public override bool CanSeek { get { return m_stream.CanSeek; } }
public override bool CanWrite { get { return m_stream.CanWrite; } }
public override long Length { get { return m_stream.Length - m_base_pos; } }
public override long Position
{
get { return m_stream.Position - m_base_pos; }
set { m_stream.Position = m_base_pos + value; }
}
public SteinsGateEncryptedStream (ArcView file, long offset, uint size)
{
m_stream = file.CreateStream (offset, size);
m_should_dispose = true;
m_base_pos = 0;
}
public SteinsGateEncryptedStream (Stream output)
{
m_stream = output;
m_should_dispose = false;
m_base_pos = m_stream.Position;
}
#region System.IO.Stream methods
public override void Flush()
{
m_stream.Flush();
}
public override long Seek (long offset, SeekOrigin origin)
{
if (SeekOrigin.Begin == origin)
offset += m_base_pos;
offset = m_stream.Seek (offset, origin);
return offset - m_base_pos;
}
public override void SetLength (long length)
{
throw new System.NotSupportedException ("SteinsGateEncryptedStream.SetLength method is not supported");
}
public override int Read (byte[] buffer, int offset, int count)
{
int position = (int)Position & 7;
int read = m_stream.Read (buffer, offset, count);
if (read > 0)
{
for (int i = 0; i < read; ++i)
{
buffer[offset+i] ^= NpaSteinsGateOpener.KeyString[(position+i)&7];
}
}
return read;
}
public override int ReadByte ()
{
int position = (int)Position & 7;
int b = m_stream.ReadByte();
if (-1 != b)
{
b ^= NpaSteinsGateOpener.KeyString[position];
}
return b;
}
public override void Write (byte[] buffer, int offset, int count)
{
int position = (int)Position & 7;
byte[] write_buf = new byte[count];
for (int i = 0; i < count; ++i)
{
write_buf[i] = (byte)(buffer[offset+i] ^ NpaSteinsGateOpener.KeyString[(position+i)&7]);
}
m_stream.Write (write_buf, 0, count);
}
public override void WriteByte (byte value)
{
int position = (int)Position & 7;
m_stream.WriteByte ((byte)(value ^ NpaSteinsGateOpener.KeyString[position]));
}
#endregion
#region IDisposable Members
bool disposed = false;
protected override void Dispose (bool disposing)
{
if (!disposed)
{
if (disposing && m_should_dispose)
{
m_stream.Dispose();
}
disposed = true;
base.Dispose (disposing);
}
}
#endregion
}
}