/**
* @param Buffer|null $hashStop
* @return BlockLocator
*/
public function getHeadersLocator(Buffer $hashStop = null)
{
echo 'Produce Headers locator (' . $this->chain->getIndex()->getHeight() . ') ' . PHP_EOL;
$height = $this->chain->getIndex()->getHeight();
return $this->getLocator($height, $hashStop);
}
/**
* We use this to help other nodes sync headers. Identify last common
* hash in our chain
*
* @param Chain $activeChain
* @param BlockLocator $locator
* @return false|string
*/
public function findFork(Chain $activeChain, BlockLocator $locator)
{
if ($this->debug) {
echo "db: called findFork\n";
}
$hashes = [$activeChain->getIndex()->getHash()];
foreach ($locator->getHashes() as $hash) {
$hashes[] = $hash->getHex();
}
$placeholders = rtrim(str_repeat('?, ', count($hashes) - 1), ', ');
$stmt = $this->dbh->prepare("\n SELECT node.hash\n FROM headerIndex AS node,\n headerIndex AS parent\n WHERE parent.hash = ? AND node.hash in ({$placeholders})\n ORDER BY node.rgt LIMIT 1\n ");
if ($stmt->execute($hashes)) {
$column = $stmt->fetch();
$stmt->closeCursor();
return $column['hash'];
}
throw new \RuntimeException('Failed to execute findFork');
}