git-svn-id: svn://svn.ijw.co.nz/svn/OpenRa@1062 993157c7-ee19-0410-b2c4-bb4e9862e678

OpenRa.FileFormats/PackageEntry.cs

@@ -0,0 +1,63 @@
+using System;
+using System.Collections.Generic;
+using System.Text;
+using System.IO;
+
+namespace OpenRa.FileFormats
+{
+	public class PackageEntry
+	{
+		public readonly uint Hash;
+		public readonly uint Offset;
+		public readonly uint Length;
+
+		public PackageEntry(BinaryReader r)
+		{
+			Hash = r.ReadUInt32();
+			Offset = r.ReadUInt32();
+			Length = r.ReadUInt32();
+		}
+
+		public override string ToString()
+		{
+			string filename;
+			if (Names.TryGetValue(Hash, out filename))
+				return string.Format("{0} - offset 0x{1:x8} - length 0x{2:x8}", filename, Offset, Length);
+			else
+				return string.Format("0x{0:x8} - offset 0x{1:x8} - length 0x{2:x8}", Hash, Offset, Length);
+		}
+
+		public static uint HashFilename(string name)
+		{
+			if (name.Length > 12)
+				name = name.Substring(0, 12);
+
+			name = name.ToUpperInvariant();
+			if (name.Length % 4 != 0)
+				name = name.PadRight(name.Length + (4 - name.Length % 4), '\0');
+
+			MemoryStream ms = new MemoryStream(Encoding.ASCII.GetBytes(name));
+			BinaryReader reader = new BinaryReader(ms);
+
+			uint result = 0;
+			try
+			{
+				while(true)
+					result = ((result << 1) | (result >> 31)) + reader.ReadUInt32();
+			}
+			catch (EndOfStreamException) { }
+
+			return result;
+		}
+
+		static Dictionary<uint, string> Names = new Dictionary<uint,string>();
+		
+		public static void AddStandardName(string s)
+		{
+			uint hash = HashFilename(s);
+			Names.Add(hash, s);
+		}
+
+		public const int Size = 12;
+	}
+}