/// <summary>
/// Performs a low-level scan of the storage file to yield all Key/Value pairs it was able to read from the file.
/// </summary>
/// <param name="options"> The options normally used to create the <see cref="BPlusTree{TKey, TValue}"/> instance </param>
/// <param name="sharing"> <see cref="FileShare"/> options used to open the file </param>
/// <returns> Yields the Key/Value pairs found in the file </returns>
public static IEnumerable <KeyValuePair <TKey, TValue> > RecoveryScan(Options options, FileShare sharing)
{
options = options.Clone();
options.CreateFile = CreatePolicy.Never;
string filename = options.FileName;
if (String.IsNullOrEmpty(filename))
{
throw new InvalidConfigurationValueException("FileName", "The FileName property was not specified.");
}
if (!File.Exists(filename))
{
throw new InvalidConfigurationValueException("FileName", "The FileName specified does not exist.");
}
if (options.StorageType != StorageType.Disk)
{
throw new InvalidConfigurationValueException("StorageType", "The storage type is not set to 'Disk'.");
}
using (FragmentedFile file = new FragmentedFile(filename, options.FileBlockSize, 1, 1, FileAccess.Read, sharing, FileOptions.None))
{
NodeSerializer nodeReader = new NodeSerializer(options, new NodeHandleSerializer(new Storage.BTreeFileStore.HandleSerializer()));
foreach (KeyValuePair <long, Stream> block in file.ForeachBlock(true, false, IngoreDataInvalid))
{
List <KeyValuePair <TKey, TValue> > found = new List <KeyValuePair <TKey, TValue> >();
try
{
foreach (KeyValuePair <TKey, TValue> entry in nodeReader.RecoverLeaf(block.Value))
{
found.Add(entry);
}
}
catch
{ /* Serialization error: Ignore and continue */ }
foreach (KeyValuePair <TKey, TValue> entry in found)
{
yield return(entry);
}
}
}
}
