// hashInSlice returns whether a hash exists in a slice or not.
func hashInSlice(h *chainhash.Hash, list []*chainhash.Hash) bool {
for _, hash := range list {
if h.IsEqual(hash) {
return true
}
}
return false
}
// removeStakePoolInvalUserTickets removes the ticket hash from the inval
// ticket bucket.
func removeStakePoolInvalUserTickets(ns walletdb.ReadWriteBucket, scriptHash [20]byte,
record *chainhash.Hash) error {
// Fetch the current content of the key.
// Possible buggy behaviour: If deserialization fails,
// we won't detect it here. We assume we're throwing
// ErrPoolUserInvalTcktsNotFound.
oldRecords, _ := fetchStakePoolUserInvalTickets(ns, scriptHash)
// Don't need to remove records that don't exist.
if !duplicateExistsInInvalTickets(record, oldRecords) {
return nil
}
var newRecords []*chainhash.Hash
for i := range oldRecords {
if record.IsEqual(oldRecords[i]) {
newRecords = append(oldRecords[:i:i], oldRecords[i+1:]...)
}
}
if newRecords == nil {
return nil
}
bucket := ns.NestedReadWriteBucket(metaBucketName)
key := make([]byte, stakePoolInvalidPrefixSize+scriptHashSize)
copy(key[0:stakePoolInvalidPrefixSize], stakePoolInvalidPrefix)
copy(key[stakePoolInvalidPrefixSize:stakePoolInvalidPrefixSize+scriptHashSize],
scriptHash[:])
// Write the serialized invalid user ticket hashes.
serializedRecords := serializeUserInvalTickets(newRecords)
err := bucket.Put(key, serializedRecords)
if err != nil {
str := fmt.Sprintf("failed to store pool user invalid ticket "+
"records '%x'", scriptHash)
return stakeStoreError(ErrDatabase, str, err)
}
return nil
}
// BlockLocatorFromHash returns a block locator for the passed block hash.
// See BlockLocator for details on the algotirhm used to create a block locator.
//
// In addition to the general algorithm referenced above, there are a couple of
// special cases which are handled:
//
// - If the genesis hash is passed, there are no previous hashes to add and
// therefore the block locator will only consist of the genesis hash
// - If the passed hash is not currently known, the block locator will only
// consist of the passed hash
func (b *BlockChain) BlockLocatorFromHash(hash *chainhash.Hash) BlockLocator {
// The locator contains the requested hash at the very least.
locator := make(BlockLocator, 0, wire.MaxBlockLocatorsPerMsg)
locator = append(locator, hash)
// Nothing more to do if a locator for the genesis hash was requested.
if hash.IsEqual(b.chainParams.GenesisHash) {
return locator
}
// Attempt to find the height of the block that corresponds to the
// passed hash, and if it's on a side chain, also find the height at
// which it forks from the main chain.
blockHeight := int64(-1)
forkHeight := int64(-1)
node, exists := b.index[*hash]
if !exists {
// Try to look up the height for passed block hash. Assume an
// error means it doesn't exist and just return the locator for
// the block itself.
height, err := b.db.FetchBlockHeightBySha(hash)
if err != nil {
return locator
}
blockHeight = height
} else {
blockHeight = node.height
// Find the height at which this node forks from the main chain
// if the node is on a side chain.
if !node.inMainChain {
for n := node; n.parent != nil; n = n.parent {
if n.inMainChain {
forkHeight = n.height
break
}
}
}
}
// Generate the block locators according to the algorithm described in
// in the BlockLocator comment and make sure to leave room for the
// final genesis hash.
iterNode := node
increment := int64(1)
for len(locator) < wire.MaxBlockLocatorsPerMsg-1 {
// Once there are 10 locators, exponentially increase the
// distance between each block locator.
if len(locator) > 10 {
increment *= 2
}
blockHeight -= increment
if blockHeight < 1 {
break
}
// As long as this is still on the side chain, walk backwards
// along the side chain nodes to each block height.
if forkHeight != -1 && blockHeight > forkHeight {
// Intentionally use parent field instead of the
// getPrevNodeFromNode function since we don't want to
// dynamically load nodes when building block locators.
// Side chain blocks should always be in memory already,
// and if they aren't for some reason it's ok to skip
// them.
for iterNode != nil && blockHeight > iterNode.height {
iterNode = iterNode.parent
}
if iterNode != nil && iterNode.height == blockHeight {
locator = append(locator, iterNode.hash)
}
continue
}
// The desired block height is in the main chain, so look it up
// from the main chain database.
h, err := b.db.FetchBlockShaByHeight(blockHeight)
if err != nil {
// This shouldn't happen and it's ok to ignore block
// locators, so just continue to the next one.
log.Warnf("Lookup of known valid height failed %v",
blockHeight)
continue
}
locator = append(locator, h)
}
// Append the appropriate genesis block.
locator = append(locator, b.chainParams.GenesisHash)
return locator
}