public void WriteEntry(Entry entry)
{
int entrySize = entry.GetTotalSize(LastPosition);
if (entrySize + TocEntrySize > _spaceLeft)
{
throw new Exception("Not enough space to write entry.");
}
if (EntryCount == 0)
{
FirstEntry = entry;
}
SpanWriter blockWriter = new SpanWriter(Buffer);
blockWriter.Position = LastPosition;
// Begin to write the entry's common information
// Not actually BE, both are writen as indexing buffer
int entryOffset = blockWriter.Position;
blockWriter.Endian = Endian.Big;
blockWriter.WriteInt32(entry.ParentNode);
blockWriter.Endian = Endian.Little;
blockWriter.WriteStringRaw(entry.Name);
blockWriter.Align(0x04); // Entry is aligned
// Write type specific
int entryMetaOffset = blockWriter.Position;
entry.SerializeTypeMeta(ref blockWriter);
blockWriter.Align(0x04); // Whole entry is also aligned
LastPosition = blockWriter.Position;
_spaceLeft -= entrySize + TocEntrySize; // Include the block's toc entry
// Write the lookup information at the end of the block
blockWriter.Position = BlockSize - ((EntryCount + 1) * TocEntrySize);
blockWriter.WriteUInt16((ushort)entryOffset);
blockWriter.WriteUInt16((ushort)entry.GetEntryMetaSize());
blockWriter.WriteUInt16((ushort)entryMetaOffset);
blockWriter.WriteUInt16(entry.GetTypeMetaSize());
// Move on to next.
EntryCount++;
}
public void WriteNextDataEntry(Entry lastPrevBlockEntry, Entry firstNextBlockEntry)
{
var blockWriter = new SpanWriter(Buffer);
blockWriter.Position = LastPosition;
byte[] indexer = CompareEntries(lastPrevBlockEntry, firstNextBlockEntry);
int actualSpace = MeasureEntrySize(blockWriter.Position, indexer);
int entrySize = indexer.Length;
if (actualSpace > _spaceLeft)
{
throw new Exception("Not enough space to write index entry.");
}
// Begin to write the entry's common information
int entryOffset = blockWriter.Position;
blockWriter.WriteBytes(indexer);
blockWriter.Align(0x04); // Entry is aligned
int endPos = blockWriter.Position;
_spaceLeft -= actualSpace + TocEntrySize; // Include the block's toc entry
// Write the lookup information at the end of the block
blockWriter.Position = BlockSize - ((EntryCount + 1) * TocEntrySize);
blockWriter.WriteUInt16((ushort)entryOffset);
blockWriter.WriteUInt16((ushort)entrySize);
blockWriter.WriteUInt32(0); // We will write the block index later as we don't have it
// Move on to next.
EntryCount++;
LastPosition = endPos;
}
