public void AddOrUpdateEntry(PageSummary summary)
{
if (!indices.Keys.Contains(summary.AddressSpaceId))
{
indices[summary.AddressSpaceId] = new List <PageSummary>();
}
if (!summary.PageFileIndex.HasValue)
{
stream.Position = stream.Length;
indices[summary.AddressSpaceId].Add(summary);
endOfIndex = Math.Max((summary.DataFileOffset + summary.Size), endOfIndex);
}
else
{
stream.Position = summary.PageFileIndex.Value;
if (!indices[summary.AddressSpaceId].Contains(summary))
{
//foreach (var space in indices.Values)
//{
// if (space.Contains(summary)) space.Remove(summary);
//}
EmptyPages.Remove(summary);
indices[summary.AddressSpaceId].Add(summary);
summary.Allocated = true;
}
}
summary.WriteToStream(writer);
}
public PageIndex(Stream stream)
{
endOfIndex = 0;
this.stream = stream;
reader = new BinaryReader(stream);
writer = new BinaryWriter(stream);
indices = new Dictionary <Guid, List <PageSummary> >();
indices[Guid.Empty] = new List <PageSummary>();
PageSummary summary = null;
do
{
summary = PageSummary.ReadFromStream(reader);
if (summary != null)
{
if (!indices.Keys.Contains(summary.AddressSpaceId))
{
indices.Add(summary.AddressSpaceId, new List <PageSummary>());
}
indices[summary.AddressSpaceId].Add(summary);
endOfIndex = summary.DataFileOffset + summary.Size;
}
} while (summary != null);
}
public void ExpandAddressSpace(Guid addressSpaceId, long localOffset)
{
if (!EmptyPages.Any())
{
IndexFileGrowth();
}
PageSummary summary = EmptyPages[0];
summary.AddressSpaceId = addressSpaceId;
summary.LocalAddressSpaceOffset = localOffset;
AddOrUpdateEntry(summary);
}
public void IndexFileGrowth()
{
for (int i = 0; i < DbEngineConfigurationSection.ConfigSection.VfsConfig.PageIncreaseNum; i++)
{
PageSummary newSummary = new PageSummary();
newSummary.AddressSpaceId = Guid.Empty;
newSummary.Allocated = false;
newSummary.DataFileOffset = EndOfPageIndex;
newSummary.Size = DbEngineConfigurationSection.ConfigSection.VfsConfig.PageSizeInKb;
newSummary.Used = 0;
AddOrUpdateEntry(newSummary);
}
}
public static PageSummary ReadFromStream(BinaryReader reader)
{
if (reader.BaseStream.Position == reader.BaseStream.Length)
{
return(null);
}
PageSummary summary = new PageSummary();
summary.pageFileIndex = reader.BaseStream.Position;
summary.addressSpaceId = new Guid(reader.ReadBytes(16));
summary.size = reader.ReadInt32();
summary.used = reader.ReadInt32();
summary.offset = reader.ReadInt64();
summary.localOffset = reader.ReadInt64();
summary.allocated = reader.ReadBoolean();
return(summary);
}