public ClassEntry Search(string className)
{
if (m_name_cache.ContainsKey(className))
{
ClassEntry result = (ClassEntry)m_name_cache[className];
result.BreakLinks();
result.BuildLinks(m_LRU, m_LRU.Next);
return(result);
}
else
{
//not in cache, get it from disk
KCatalog target = new KCatalog(className);
KCatalog t = (KCatalog)m_tree.Search(target);
if (t != null)
{
_put_in_cache(t.ClassInfo.CId, className, t.ClassInfo.FieldNames, t.ClassInfo.TopNodeSId);
return((ClassEntry)m_cid_cache[t.ClassInfo.CId]);
}
else
{
return(null);
}
}
}
/// <summary>
/// Given the segment id, return the offset, and the length of the segment related to the disk file.
/// </summary>
/// <param name="segId"></param>
/// <param name="offset"></param>
/// <param name="length"></param>
/// <returns></returns>
public bool GetAddr(uint segId, ref uint offset, ref int length)
{
KSegId target = new KSegId(segId);
target = (KSegId)m_tree.Search(target);
if (target != null && target.Addr != null)
{
offset = target.Addr.Offset;
length = target.Addr.Length;
return(true);
}
else
{
return(false);
}
}
public ObjectInfo SearchObject(object keyValue)
{
KClass key = new KClass(keyValue, OOD.Types.GetInternalType(keyValue.GetType()));
KClass obj = (KClass)m_tree.Search(key);
if (obj != null)
{
Debug.Assert(obj.SerializedOtherData != null);
ObjectInfo result = new ObjectInfo(key.DataType, key.KValue, obj.SerializedOtherData.SerializedValues);
return(result);
}
else
{
return(null);
}
}
/* Needed operations:
* 1. Given an offset and length, set that range to be free space.
* 2. Given an length, return the pair (offset, length) can be used.
* that range will be removed from free space tree before this
* operation returns.
*/
/// <summary>
/// Set the segment in the databse file to be free.
/// </summary>
/// <param name="offset"></param>
/// <param name="length"></param>
public void SetSegmentFree(uint offset, int length)
{
if (offset + length != m_dbFile.Length)
{
uint nextSeg = (uint)(offset + length);
KOffset target = new KOffset(nextSeg);
KOffset finding = (KOffset)m_tree.Search(target);
if (finding == null)
{
//combine to next segment is not possible, just go ahead to insert this one
target.Offset = offset;
target.Length = new DLength(length);
if (m_tree.Insert(target) == false)
{
throw new OOD.Exception.ProgramLogicError(
this,
"Insert into free space b-tree failed.");
}
}
else
{
//combine these two free segment into a big one
length += finding.Length.Num;
target.Length = new DLength(length);
target.Offset = offset;
if (m_tree.Delete(finding) == false || m_tree.Insert(target) == false)
{
throw new OOD.Exception.ProgramLogicError(
this,
"Delete free space failed.");
}
}
}
else
{
//this is the last segment in the database file, just remove it from the file
m_dbFile.SetLength(offset);
}
}