Files
OpenRA/OpenRA.Game/FileSystem/Pak.cs
2016-02-21 16:30:48 +00:00

85 lines
1.9 KiB
C#

#region Copyright & License Information
/*
* Copyright 2007-2016 The OpenRA Developers (see AUTHORS)
* This file is part of OpenRA, which is free software. It is made
* available to you under the terms of the GNU General Public License
* as published by the Free Software Foundation, either version 3 of
* the License, or (at your option) any later version. For more
* information, see COPYING.
*/
#endregion
using System.Collections.Generic;
using System.IO;
namespace OpenRA.FileSystem
{
struct Entry
{
public uint Offset;
public uint Length;
public string Filename;
}
public sealed class PakFile : IReadOnlyPackage
{
public string Name { get; private set; }
public IEnumerable<string> Contents { get { return index.Keys; } }
readonly Dictionary<string, Entry> index;
readonly Stream stream;
public PakFile(FileSystem context, string filename)
{
Name = filename;
index = new Dictionary<string, Entry>();
stream = context.Open(filename);
try
{
index = new Dictionary<string, Entry>();
var offset = stream.ReadUInt32();
while (offset != 0)
{
var file = stream.ReadASCIIZ();
var next = stream.ReadUInt32();
var length = (next == 0 ? (uint)stream.Length : next) - offset;
// Ignore duplicate files
if (index.ContainsKey(file))
continue;
index.Add(file, new Entry { Offset = offset, Length = length, Filename = file });
offset = next;
}
}
catch
{
Dispose();
throw;
}
}
public Stream GetStream(string filename)
{
Entry entry;
if (!index.TryGetValue(filename, out entry))
return null;
stream.Seek(entry.Offset, SeekOrigin.Begin);
var data = stream.ReadBytes((int)entry.Length);
return new MemoryStream(data);
}
public bool Contains(string filename)
{
return index.ContainsKey(filename);
}
public void Dispose()
{
stream.Dispose();
}
}
}