Method GetBlockHashesFromHash

core/headerchain.go:284–303

GetBlockHashesFromHash retrieves a number of block hashes starting at a given hash, fetching towards the genesis block.

(hash common.Hash, max uint64)

// GetBlockHashesFromHash retrieves a number of block hashes starting at a given
// hash, fetching towards the genesis block.
func (hc *HeaderChain) GetBlockHashesFromHash(hash common.Hash, max uint64) []common.Hash {
	// Get the origin header from which to fetch
	header := hc.GetHeaderByHash(hash)
	if header == nil {
		return nil
	}
	// Iterate the headers until enough is collected or the genesis reached
	chain := make([]common.Hash, 0, max)
	for i := uint64(0); i < max; i++ {
		next := header.ParentHash
		if header = hc.GetHeader(next, header.Number.Uint64()-1); header == nil {
			break
		}
		chain = append(chain, next)
		if header.Number.Sign() == 0 {
			break
		}
	}
	return chain
}

// GetAncestor retrieves the Nth ancestor of a given block. It assumes that either the given block or
// a close ancestor of it is canonical. maxNonCanonical points to a downwards counter limiting the