/// <summary>
/// Write header data from variable into byte[] buffer. When override, call base.UpdateBuffer() after write your code
/// </summary>
public virtual PageBuffer UpdateBuffer()
{
// using fixed position to be faster than BufferWriter
ENSURE(this.PageID == _buffer.ReadUInt32(P_PAGE_ID), "pageID can't be changed");
// page information
// PageID - never change!
_buffer.Write(this.PrevPageID, P_PREV_PAGE_ID);
_buffer.Write(this.NextPageID, P_NEXT_PAGE_ID);
_buffer.Write(this.PageListSlot, P_INITIAL_SLOT);
// transaction information
_buffer.Write(this.TransactionID, P_TRANSACTION_ID);
_buffer.Write(this.IsConfirmed, P_IS_CONFIRMED);
_buffer.Write(this.ColID, P_COL_ID);
// segments information
_buffer.Write(this.ItemsCount, P_ITEMS_COUNT);
_buffer.Write(this.UsedBytes, P_USED_BYTES);
_buffer.Write(this.FragmentedBytes, P_FRAGMENTED_BYTES);
_buffer.Write(this.NextFreePosition, P_NEXT_FREE_POSITION);
_buffer.Write(this.HighestIndex, P_HIGHEST_INDEX);
return(_buffer);
}
/// <summary>
/// Read header data from byte[] buffer into local variables
/// using fixed position be be faster than use BufferReader
/// </summary>
public BasePage(PageBuffer buffer)
{
_buffer = buffer;
// page information
this.PageID = _buffer.ReadUInt32(P_PAGE_ID);
this.PageType = (PageType)_buffer.ReadByte(P_PAGE_TYPE);
this.PrevPageID = _buffer.ReadUInt32(P_PREV_PAGE_ID);
this.NextPageID = _buffer.ReadUInt32(P_NEXT_PAGE_ID);
// transaction information
this.TransactionID = _buffer.ReadUInt32(P_TRANSACTION_ID);
this.IsConfirmed = _buffer.ReadBool(P_IS_CONFIRMED);
this.ColID = _buffer.ReadUInt32(P_COL_ID);
// blocks information
this.ItemsCount = _buffer.ReadByte(P_ITEMS_COUNT);
this.UsedBytes = _buffer.ReadUInt16(P_USED_BYTES);
this.FragmentedBytes = _buffer.ReadUInt16(P_FRAGMENTED_BYTES);
this.NextFreePosition = _buffer.ReadUInt16(P_NEXT_FREE_POSITION);
this.HighestIndex = _buffer.ReadByte(P_HIGHEST_INDEX);
}