public void Execute(uint stage, SharpMedia.Database.Physical.Journalling.IService service)
{
// 1) We read previous object placement and change it.
ObjectInfo info = childrenTree.Find(service, (uint)prevName.GetHashCode());
BlockStream stream = BlockStream.FromBase(info.Address, service);
ChildTag childTag = Common.DeserializeFromArray(stream.Read(info.Size)) as ChildTag;
childTag.Remove(prevName);
// Remove it if empty.
if (childTag.IsEmpty)
{
childrenTree.Remove(service, (uint)prevName.GetHashCode(), 1, false);
}
else
{
// Update the entry (now without this child).
byte[] childTagData = Common.SerializeToArray(childTag);
stream = service.AllocationContext.CreateBlockStream((ulong)childTagData.LongLength);
stream.Write(childTagData);
childrenTree.Replace(service,
new ObjectInfo((uint)prevName.GetHashCode(), (ulong)childTagData.LongLength, stream.BaseAddress));
}
// 3) We create new and insert it into tree.
ObjectInfo info2 = childrenTree.Find(service, (uint)newName.GetHashCode());
if (info2 == null)
{
// We create new tag.
childTag = new ChildTag();
childTag.Add(newName, info.Address);
byte[] childTagData = Common.SerializeToArray(childTag);
stream = service.AllocationContext.CreateBlockStream((ulong)childTagData.LongLength);
stream.Write(childTagData);
// And we add child.
childrenTree.Add(service,
new ObjectInfo((uint)newName.GetHashCode(), (ulong)childTagData.LongLength, stream.BaseAddress));
}
else
{
// We append it and release previous tag.
stream = BlockStream.FromBase(info2.Address, service);
childTag = Common.DeserializeFromArray(stream.Read(info2.Size)) as ChildTag;
stream.Deallocate();
// We modify and rewrite it.
childTag.Add(newName, info.Address);
byte[] childTagData = Common.SerializeToArray(childTag);
stream = service.AllocationContext.CreateBlockStream((ulong)childTagData.LongLength);
stream.Write(childTagData);
// We insert into children tree.
childrenTree.Replace(service,
new ObjectInfo((uint)newName.GetHashCode(), (ulong)childTagData.LongLength, info.Address));
}
}
public unsafe void Execute(uint stage, IService service)
{
// 1) We create the node common block.
versionAddress = service.AllocationContext.AllocateBlock();
commonAddress = service.AllocationContext.AllocateBlock();
BPlusTree versionTS = new BPlusTree(service.AllocationContext.CreateEmptyBTree());
// Fill common block and write.
Block commonBlock = new Block(service.BlockSize);
fixed(byte *p = commonBlock.Data)
{
NodeCommonHeader *header = (NodeCommonHeader *)p;
header->ChildrenBTree = service.AllocationContext.CreateEmptyBTree();
header->CurrentVersionAddress = versionAddress;
header->CurrentVersionNumber = 0;
header->HeaderMagic = NodeCommonHeader.Magic;
header->ParentAddress = parentAddress;
header->VersionsBTree = versionTS.RootAddress;
}
service.Write(BlockType.NodeHeaderBlock, commonAddress, commonBlock);
// 2) We create the node default typed stream.
Block tsblock = new Block(service.BlockSize);
ulong tsBlock = service.AllocationContext.AllocateBlock();
fixed(byte *p = tsblock.Data)
{
TypedStreamHeader *header = (TypedStreamHeader *)p;
header->ObjectsAddress = (defaultTSOptions & StreamOptions.SingleObject) == 0 ?
service.AllocationContext.CreateEmptyBTree() : 0;
header->Options = defaultTSOptions;
header->ObjectSize = 0;
int i;
for (i = 0; i < defaultTSType.Length; i++)
{
header->Type[i] = defaultTSType[i];
}
// Null terminate it.
header->Type[i] = '\0';
}
service.Write(BlockType.TypedStreamHeader, tsBlock, tsblock);
// 3) We create the node version block.
// Fill version block and write.
Block versionBlock = new Block(service.BlockSize);
fixed(byte *pp = versionBlock.Data)
{
NodeVersionHeader *header = (NodeVersionHeader *)pp;
header->CreationTime = DateTime.Now;
header->DefaultTypedStream = 0;
header->HeaderMagic = NodeVersionHeader.Magic;
header->ModifiedTime = DateTime.Now;
header->NodeCommonAddress = commonAddress;
header->StreamCount = 0; //< Is actually one but NodeHelper changes this.
header->VersionNumber = 0;
}
// We must add default typed stream to block.
NodeVersionHelper.AddTypedStream(tsBlock, defaultTSType, versionBlock);
service.Write(BlockType.NodeHeaderBlock, versionAddress, versionBlock);
// 4) We add to children tree.
ObjectInfo info = childrenTree.Find(service, (uint)childName.GetHashCode());
if (info == null)
{
// We simply create a new object at address.
ChildTag childTag = new ChildTag();
childTag.HashCode = childName.GetHashCode();
childTag.Add(childName, commonAddress);
byte[] childData = Common.SerializeToArray(childTag);
// We write it to block stream.
BlockStream stream = service.AllocationContext.CreateBlockStream((ulong)childData.LongLength);
stream.Write(childData);
// We now add it to B+ tree.
childrenTree.Add(service, new ObjectInfo((uint)childName.GetHashCode(), (ulong)childData.LongLength, stream.BaseAddress));
}
else
{
// The index at hash already exists, we must add it, first read it.
BlockStream stream = BlockStream.FromBase(info.Address, service);
ChildTag childTag = Common.DeserializeFromArray(stream.Read(info.Size)) as ChildTag;
// Steam not used anymore.
stream.Deallocate();
// We modify child tag.
childTag.Add(childName, commonAddress);
byte[] childData = Common.SerializeToArray(childTag);
// We must write it to new address.
stream = service.AllocationContext.CreateBlockStream((ulong)childData.LongLength);
stream.Write(childData);
// Now we replace the data in tree.
childrenTree.Replace(service,
new ObjectInfo((uint)childName.GetHashCode(), (ulong)childData.LongLength, stream.BaseAddress));
}
// 5) Add version to typed stream.
VersionTag versionTag = new VersionTag((0).GetHashCode());
versionTag.Add(0, versionAddress);
byte[] versionTagData = Common.SerializeToArray(versionTag);
// Write to stream.
BlockStream versionTagStream = service.AllocationContext.CreateBlockStream((ulong)versionTagData.LongLength);
versionTagStream.Write(versionTagData);
versionTS.Add(service, new ObjectInfo((uint)(0).GetHashCode(),
(ulong)versionTagData.LongLength, versionTagStream.BaseAddress));
}
