public void OnNodeConnected(BitcoinEndpoint endpoint)
{
BlockLocator locator = null;
lock (lockObject)
{
endpoints.Add(endpoint, new EndpointState(endpoint));
if (requiredBlocks.Any())
{
int minRequiredBlockHeight = requiredBlocks.Values.Min(b => b.Height);
int locatorHeight = minRequiredBlockHeight - 1;
List<StoredBlock> parentBlocks = node.Blockchain.GetBlocksByHeight(BlockLocator.GetRequiredBlockHeights(locatorHeight));
locator = new BlockLocator();
foreach (StoredBlock block in parentBlocks)
{
locator.AddHash(block.Height, block.Hash);
}
}
}
if (locator != null)
{
endpoint.WriteMessage(new GetBlocksMessage(endpoint.ProtocolVersion, locator.GetHashes(), new byte[32]));
}
}
private void ProcessHeadersMessage(BitcoinEndpoint endpoint, HeadersMessage message)
{
List<StoredBlock> storedBlocks = node.Blockchain.AddHeaders(message.Headers);
//todo: save blockLocator per node between requests?
BlockLocator blockLocator = new BlockLocator();
//todo: what should happen if message contains headers from different branchas?
bool hasSavedHeaders = false;
foreach (StoredBlock block in storedBlocks)
{
if (block.Height >= 0)
{
//todo: this code assumes that blocks in storedBlocks collections are in order of ascending height and belong to one branch
blockLocator.AddHash(block.Height, block.Hash);
hasSavedHeaders = true;
}
}
//todo: review this condition
if (hasSavedHeaders)
{
RequestHeaders(endpoint, blockLocator);
}
}
public void TestTruncation()
{
BlockLocator locator = new BlockLocator();
for (int i = 1; i <= 20; i++)
{
locator.AddHash(i, BitConverter.GetBytes(i));
}
Assert.That(locator.GetHashes().Select(val => BitConverter.ToInt32(val, 0)), Is.EqualTo(new int[]
{
20, 19, 18, 17, 16, 15, 14, 13, 12, 11, 8, 4
}));
locator.AddHash(16, BitConverter.GetBytes(10016));
Assert.That(locator.GetHashes().Select(val => BitConverter.ToInt32(val, 0)), Is.EqualTo(new int[]
{
10016, 15, 14, 13, 12, 11, 8, 4
}));
}
private static void RequestHeaders(BitcoinEndpoint endpoint, BlockLocator blockLocator)
{
endpoint.WriteMessage(new GetHeadersMessage(endpoint.ProtocolVersion, blockLocator.GetHashes(), new byte[32]));
}
private void TestSet(int from, int to)
{
BlockLocator locator = new BlockLocator();
for (int i = from; i <= to; i++)
{
locator.AddHash(i, BitConverter.GetBytes(i));
}
Assert.That(
locator.GetHashes().Select(val => BitConverter.ToInt32(val, 0)).ToList(),
Is.EqualTo(CalculateExpectedHeights(from, to)),
$"Testing set from {from} to {to}.");
}