Very old C# code for reading a binary iTunes Library file

iTunesDBLoader.cs

using System;
using System.Windows.Forms;
using System.IO;
using System.Text;

namespace iTunesDBBrowser
{
	public delegate void UpdateFormDelegate(Song song, long bytes, long totalbytes);

	public struct Song
	{
		public string Title;
		public string Artist;
		public string Album;
		public string Filename;

		public void Clear()
		{
			Title = Artist = Album = Filename = "";
		}

		public void SetField(Code c, string s)
		{
			switch(c)
			{
				case Code.Title:
					Title = s;
					break;
				case Code.Filename:
					Filename = s;
					break;
				case Code.Artist:
					Artist = s;
					break;
				case Code.Album:
					Album = s;
					break;
				default:
					break;
			}
		}
	}

	public enum Code
	{
		Title = 1,
		Filename = 2,
		Album = 3,
		Artist = 4,
		Genre = 5,
		Filetype = 6,
		Unknown = 7,
		Comment = 8,
		Unknown2 = 100
	}

	public struct fsbbStruct
	{
		public string pad;  // 2 bytes
		public string code; // 2 bytes
		public uint jump;
		public uint myLen;
		public uint count;
	}

	struct stringParam
	{
		public uint res1;
		public uint strlength;
		public uint[] res2; // = new uint[2];
	}

	struct propertyParam
	{
		public uint item_id;
		public uint[] res1; //  = new uint[3]
	}
/*
	struct playlistParam
	{
		public uint[] res1; // = new uint[2];
		public uint item_ref;
		public ushort[] res2; // = new ushort[2];
	}
*/

	/// <summary>
	/// Loads an iTunesDB file
	/// </summary>
	public class iTunesDBLoader
	{
		private FileInfo file;
		private FileStream fs;
		private BinaryReader br;
		private MainForm mf;
		private UpdateFormDelegate ufd;
		private string fileBase;
		private bool debug = false;
		private StreamWriter sw = null;

		public iTunesDBLoader(FileInfo file, MainForm mf, UpdateFormDelegate ufd)
		{
			this.file = file;
			this.mf = mf;
			this.ufd = ufd;

			// determine fileBase
			fileBase = file.Directory.Root.ToString();
		}

		public bool Debug
		{
			get
			{
				return debug;
			}

			set
			{
				debug = value;
			}
		}

		private fsbbStruct ReadHeader()
		{
			fsbbStruct buf;
			Encoding ascii = System.Text.Encoding.ASCII;

			byte[] bytes;
			bytes = br.ReadBytes(2);
			buf.pad = ascii.GetString(bytes);
			bytes = br.ReadBytes(2);
			buf.code = ascii.GetString(bytes);
			buf.jump = br.ReadUInt32();
			buf.myLen = br.ReadUInt32();
			buf.count = br.ReadUInt32();

			return buf;
		}

		private propertyParam ReadPropertyParam()
		{
			propertyParam pp;
			pp.item_id = br.ReadUInt32();
			pp.res1 = new uint[3];
			for(int i=0;i<3;i++)
				pp.res1[i] = br.ReadUInt32();

			return pp;
		}

		private stringParam ReadStringParam()
		{
			stringParam sp;
			sp.res1 = br.ReadUInt32();
			sp.strlength = br.ReadUInt32();
			sp.res2 = new uint[2];
			sp.res2[0] = br.ReadUInt32();
			sp.res2[1] = br.ReadUInt32();

			return sp;
		}

		private void log(string format, params object[] args)
		{
			if(debug && sw != null)
				sw.WriteLine(format, args);
		}

		public void Load()
		{
			long fileSize = file.Length;
			long bytesRead = 0;						

			if(debug)
				sw = File.CreateText(Path.Combine(Application.StartupPath,"debug.log"));

			using(fs = file.OpenRead())
			{					
				Encoding utf16 = System.Text.Encoding.GetEncoding("UTF-16");
				br = new BinaryReader(fs, utf16);
				Song curSong = new Song();
				uint numSongs = 0, songsLeft = 0, numProps = 0;
					
				while(fs.Position <= fileSize)
				{
					bytesRead = fs.Position;
					fsbbStruct fsbb = ReadHeader();
					if( fsbb.code == "bd" )		// Start code
					{
						log("{0:x6} Beginning of database", bytesRead);
					}						
					else if( fsbb.code == "sd")		// a list starter
					{
						if( fsbb.count == 1)
							log("{0:x6} List of Songs:", bytesRead);
						else if( fsbb.count == 2 )
							log("{0:x6} List of Playlists:", bytesRead);						
						else
							log("{0:x6} Unknown {1}:", bytesRead, fsbb.count);
					}
					else if( fsbb.code == "lt" )		// a list starter
					{
						log("{0:x6} {1}-item list:", bytesRead, fsbb.myLen);
						// number of songs to read
						songsLeft = numSongs = fsbb.myLen;
					}
							
					else if( fsbb.code == "ip" )		// a playlist item
					{
						//playlistParam playlist;
						//memcpy( &playlist, &contents[filepos+16], 16 );
						//log("{0:x6} itemref ({1}): XXX", bytesRead, playlist.item_ref);
						log("{0:x6} playlist item", bytesRead);
					}
					else if( fsbb.code == "it" )		// a song list item
					{
						// item_id
						propertyParam prop = ReadPropertyParam();
						log("{0:x6} {1}-property item ({2}):", bytesRead, fsbb.count, prop.item_id);
						// number of props on this song
						numProps = fsbb.count;
						curSong.Clear();
					}
					else if( fsbb.code == "od" )		// a unicode string, usually
					{
						stringParam sp;
						string str;
						log("{0:x6} Unicode String({1}) {2} {3} {4}", bytesRead, fsbb.code, fsbb.jump, fsbb.myLen, fsbb.count );
			
						sp = ReadStringParam();

						if( fsbb.myLen == 0 )		// Bad something, skip outta here
							continue;

						if( sp.strlength != 0 )
						{
							// ???
							//				memcpy( buf, &contents[filepos+40], fsbb.myLen );
							//				buf[sizeof(buf)-1] = '\0';
							//				printf("\t%s\n", buf );
						}
						else
						{
							// ??? filepos+40 below, only 32 bytes read
							// 16 in fsbb, 16 in sp
							br.ReadBytes(8);						
							str = utf16.GetString(br.ReadBytes((int)fsbb.myLen - 40));
							Code c = (Code)fsbb.count;
							log("{0}: \"{1}\"", c, str);

							if(c == Code.Filename)
							{
								// strip the leading :, replace : with the right path separator,
								// and prepend the root directory
								curSong.SetField(c, fileBase + str.Substring(1).Replace(":",Path.DirectorySeparatorChar.ToString()));
							}
							else
							{
								curSong.SetField(c, str);
							}
							numProps--;
							if(numProps == 0) // done with this song
							{
								songsLeft--;
								object[] args = new object[3]{curSong, numSongs - songsLeft, numSongs};
								mf.BeginInvoke(ufd, args);									

								if(songsLeft == 0) // done with all the songs
									break;
							}
						}
						fsbb.jump = fsbb.myLen;
					}
					else
					{
						log("{0:x6} code:{1} jump:{2} myLen:{3} count:{4}", bytesRead, fsbb.code, fsbb.jump, fsbb.myLen, fsbb.count);
					}
					if((bytesRead + fsbb.jump) > fs.Position)
					{
						fs.Seek(bytesRead + fsbb.jump - fs.Position, SeekOrigin.Current);
					}
				}
			}

			if(debug && sw != null)
				sw.Close();
		}
	}
}