internal BlockSeeker(ReadOnlySpan <byte> blockData)
{
_blockData = blockData;
_reader = new SpanReader(blockData);
Key = null;
_restartOffset = 0;
_restartCount = 0;
_comparator = new BytewiseComparator();
_lastValue = null;
Initialize();
}
public List <FileMetadata> GetOverlappingFiles(int level, byte[] smallestKey, byte[] largestKey)
{
if (!Levels.ContainsKey(level))
{
return(new List <FileMetadata>());
}
var overlappingFiles = new List <FileMetadata>();
var comparator = new BytewiseComparator();
foreach (FileMetadata metadata in GetFiles(level))
{
if (comparator.Compare(metadata.SmallestKey, largestKey) <= 0 && comparator.Compare(metadata.LargestKey, smallestKey) >= 0)
{
overlappingFiles.Add(metadata);
}
}
return(overlappingFiles);
}
public void BytewiseComparatorTest()
{
var comparator = new BytewiseComparator();
// Basic
Assert.AreEqual(Equal, comparator.Compare(new Span <byte>(), new Span <byte>()));
Assert.AreEqual(Greater, comparator.Compare(new Span <byte>(new byte[] { 0 }), new Span <byte>()));
Assert.AreEqual(Less, comparator.Compare(new Span <byte>(), new Span <byte>(new byte[] { 0 })));
Assert.AreEqual(Equal, comparator.Compare(new Span <byte>(new byte[] { 0 }), new Span <byte>(new byte[] { 0 })));
Assert.AreEqual(Equal, comparator.Compare(new Span <byte>(new byte[] { 0, 1, 2 }), new Span <byte>(new byte[] { 0, 1, 2 })));
Assert.AreEqual(Greater, comparator.Compare(new Span <byte>(new byte[] { 1 }), new Span <byte>(new byte[] { 0 })));
Assert.AreEqual(Greater, comparator.Compare(new Span <byte>(new byte[] { 1, 1 }), new Span <byte>(new byte[] { 1, 0 })));
Assert.AreEqual(Greater, comparator.Compare(new Span <byte>(new byte[] { 1, 1 }), new Span <byte>(new byte[] { 1, 0, 1 })));
Assert.AreEqual(Greater, comparator.Compare(new Span <byte>(new byte[] { 1, 1, 1 }), new Span <byte>(new byte[] { 1, 1 })));
Assert.AreEqual(Less, comparator.Compare(new Span <byte>(new byte[] { 0 }), new Span <byte>(new byte[] { 1 })));
Assert.AreEqual(Less, comparator.Compare(new Span <byte>(new byte[] { 1, 0 }), new Span <byte>(new byte[] { 1, 1 })));
Assert.AreEqual(Less, comparator.Compare(new Span <byte>(new byte[] { 1, 0, 1 }), new Span <byte>(new byte[] { 1, 1 })));
Assert.AreEqual(Less, comparator.Compare(new Span <byte>(new byte[] { 1, 1 }), new Span <byte>(new byte[] { 1, 1, 1 })));
Assert.AreEqual(Greater, comparator.Compare(new Span <byte>(new byte[] { 1, 0, 2 }), new Span <byte>(new byte[] { 1, 0, 1, 2, 3 })));
//"SmallestKey": {
// "Key": "00 00 00 00 10 00 00 00 31 01 1f 34 00 00 00 00 00 ........1..4....."
//},
//"LargestKey": {
// "Key": "ff ff ff ff fc ff ff ff 76 01 a7 42 00 00 00 00 00 ÿÿÿÿüÿÿÿv.§B....."
//}
Assert.AreEqual(Less, comparator.Compare(
new byte[] { 0x00, 0x00, 0x00, 0x00, 0x10, 0x00 },
new byte[] { 0x00, 0x00, 0x00, 0x00, 0x10, 0x00, 0x00, 0x00, 0x31, 0x01, 0x1f, 0x34, 0x00, 0x00, 0x00, 0x00, 0x00, }));
Assert.AreEqual(Greater, comparator.Compare(
new byte[] { 0x00, 0x00, 0x00, 0x00, 0x10, 0x01 },
new byte[] { 0x00, 0x00, 0x00, 0x00, 0x10, 0x00, 0x00, 0x00, 0x31, 0x01, 0x1f, 0x34, 0x00, 0x00, 0x00, 0x00, 0x00, }));
}
public void LevelDbReadLogTest()
{
// https://github.com/google/leveldb/blob/master/doc/log_format.md
DirectoryInfo directory = TestUtils.GetTestDirectory();
LogReader logReader = new LogReader(new FileInfo(Path.Combine(directory.FullName, "000047.log")));
BytewiseComparator comparator = new BytewiseComparator();
bool found = false;
while (true)
{
ReadOnlySpan <byte> data = logReader.ReadData();
if (logReader.Eof)
{
break;
}
var dataReader = new SpanReader(data);
long sequenceNumber = dataReader.ReadInt64();
long size = dataReader.ReadInt32();
while (!dataReader.Eof)
{
byte recType = dataReader.ReadByte();
ulong v1 = dataReader.ReadVarLong();
var currentKey = dataReader.Read(v1);
//CurrentKey = f5 ff ff ff eb ff ff ff 36
if (comparator.Compare(new byte[] { 0xf5, 0xff, 0xff, 0xff, 0xeb, 0xff, 0xff, 0xff, 0x36 }, currentKey) == 0)
{
Assert.False(found);
found = true;
}
ulong v2 = 0;
ReadOnlySpan <byte> currentVal = ReadOnlySpan <byte> .Empty;
switch (recType)
{
case 1: // value
{
if (recType == 1)
{
v2 = dataReader.ReadVarLong();
currentVal = dataReader.Read(v2);
}
break;
}
case 0: // delete
{
//Assert.Fail("Unexpected delete key");
break;
}
default:
throw new Exception("Unknown record format");
}
if (Log.IsDebugEnabled)
{
Log.Debug($"RecType={recType}, Sequence={sequenceNumber}, Size={size}, v1={v1}, v2={v2}\nCurrentKey={currentKey.HexDump(currentKey.Length, false, false)}\nCurrentVal=\n{currentVal.HexDump(cutAfterFive: true)} ");
}
}
}
Assert.True(found);
}
