public static void WriteToFile(Header header, BinaryWriter writer)
{
writer.BaseStream.Seek(0L, SeekOrigin.Begin);
writer.Write("FileDB".ToBytes("FileDB".Length));
writer.Write((short) 1);
writer.Write(header.IndexRootPageID);
writer.Write(header.FreeIndexPageID);
writer.Write(header.FreeDataPageID);
writer.Write(header.LastFreeDataPageID);
writer.Write(header.LastPageID);
}
public static void ReadFromFile(Header header, BinaryReader reader)
{
reader.BaseStream.Seek(0L, SeekOrigin.Begin);
if (reader.ReadString("FileDB".Length) != "FileDB")
{
throw new FileDBException("The file is not a valid storage archive");
}
if (reader.ReadInt16() != 1)
{
throw new FileDBException("The archive version is not valid");
}
header.IndexRootPageID = reader.ReadUInt32();
header.FreeIndexPageID = reader.ReadUInt32();
header.FreeDataPageID = reader.ReadUInt32();
header.LastFreeDataPageID = reader.ReadUInt32();
header.LastPageID = reader.ReadUInt32();
header.IsDirty = false;
}
public static void CreateEmptyFile(BinaryWriter writer)
{
Header header = new Header {
IndexRootPageID = 0,
FreeIndexPageID = 0,
FreeDataPageID = uint.MaxValue,
LastFreeDataPageID = uint.MaxValue,
LastPageID = 0
};
HeaderFactory.WriteToFile(header, writer);
IndexUnit pageIndex = new IndexUnit(0) {
NodeIndex = 0,
NextUnitID = uint.MaxValue
};
IndexNode indexNode = pageIndex.Nodes[0];
indexNode.ID = new Guid(new byte[] { 0x7f, 0x7f, 0x7f, 0x7f, 0x7f, 0x7f, 0x7f, 0x7f, 0x7f, 0x7f, 0x7f, 0x7f, 0x7f, 0x7f, 0x7f, 0x7f });
indexNode.IsDeleted = true;
indexNode.Right = new IndexLink();
indexNode.Left = new IndexLink();
indexNode.DataPageID = uint.MaxValue;
indexNode.FileName = string.Empty;
indexNode.FileExtension = string.Empty;
UnitFactory.WriteToFile(pageIndex, writer);
}
