/// <summary>
/// Deserializes the metadata (footer, properties, etc.) for this checkpoint file.
/// </summary>
private async Task ReadMetadataAsync()
{
Stream filestream = null;
try
{
filestream = this.ReaderPool.AcquireStream();
// Read and validate the Footer section. The footer is always at the end of the stream, minus space for the checksum.
var footerHandle = new BlockHandle(filestream.Length - FileFooter.SerializedSize - sizeof(ulong), FileFooter.SerializedSize);
this.Footer =
await FileBlock.ReadBlockAsync(filestream, footerHandle, (sectionReader, sectionHandle) => FileFooter.Read(sectionReader, sectionHandle)).ConfigureAwait(false);
// Verify we know how to deserialize this version of the checkpoint file.
if (this.Footer.Version != FileVersion)
{
throw new InvalidDataException(SR.Error_KeyCheckpointFile_Deserialized);
}
// Read and validate the Properties section.
var propertiesHandle = this.Footer.PropertiesHandle;
this.Properties =
await
FileBlock.ReadBlockAsync(
filestream,
propertiesHandle,
(sectionReader, sectionHandle) => FilePropertySection.Read <KeyCheckpointFileProperties>(sectionReader, sectionHandle)).ConfigureAwait(false);
}
finally
{
this.ReaderPool.ReleaseStream(filestream, true);
}
}
/// <summary>
/// Create a new key checkpoint file with the given filename.
/// </summary>
/// <param name="filename">Path to the checkpoint file.</param>
/// <param name="fileId">File Id of the checkpoint file.</param>
/// <param name="isValueAReferenceType"></param>
public KeyCheckpointFile(string filename, uint fileId, bool isValueAReferenceType)
: this(filename, isValueAReferenceType)
{
this.Properties = new KeyCheckpointFileProperties()
{
FileId = fileId,
};
this.isValueAReferenceType = isValueAReferenceType;
}