public void checkConsistency() throws com.google.bitcoin.store.BlockStoreException {
StoredBlock head = block_store.getChainHead();
StoredBlock curr_block = head;
Sha256Hash genisis_hash = params.getGenesisBlock().getHash();
int checked = 0;
while (true) {
Sha256Hash curr_hash = curr_block.getHeader().getHash();
if (curr_block.getHeight() % 10000 == 0) {
System.out.println("Block: " + curr_block.getHeight());
}
if (!file_db.getBlockMap().containsKey(curr_hash)) {
throw new RuntimeException("Missing block: " + curr_hash);
}
checked++;
// if (checked > 20) return;
if (curr_hash.equals(genisis_hash)) return;
curr_block = curr_block.getPrev(block_store);
}
}
@Override
protected StoredBlock addToBlockStore(
StoredBlock storedPrev, Block header, TransactionOutputChanges txOutChanges)
throws BlockStoreException, VerificationException {
StoredBlock newBlock = storedPrev.build(header);
blockStore.put(newBlock, new StoredUndoableBlock(newBlock.getHeader().getHash(), txOutChanges));
return newBlock;
}
@Override
protected StoredBlock addToBlockStore(StoredBlock storedPrev, Block block)
throws BlockStoreException, VerificationException {
StoredBlock newBlock = storedPrev.build(block);
blockStore.put(
newBlock, new StoredUndoableBlock(newBlock.getHeader().getHash(), block.transactions));
return newBlock;
}
@Override
public View getView(final int position, final View convertView, final ViewGroup parent) {
final ViewGroup row;
if (convertView == null)
row = (ViewGroup) getLayoutInflater(null).inflate(R.layout.block_row, null);
else row = (ViewGroup) convertView;
final StoredBlock storedBlock = getItem(position);
final Block header = storedBlock.getHeader();
final TextView rowHeight = (TextView) row.findViewById(R.id.block_list_row_height);
final int height = storedBlock.getHeight();
rowHeight.setText(Integer.toString(height));
final TextView rowTime = (TextView) row.findViewById(R.id.block_list_row_time);
final long timeMs = header.getTimeSeconds() * DateUtils.SECOND_IN_MILLIS;
rowTime.setText(
DateUtils.getRelativeDateTimeString(
activity, timeMs, DateUtils.MINUTE_IN_MILLIS, DateUtils.WEEK_IN_MILLIS, 0));
final TextView rowHash = (TextView) row.findViewById(R.id.block_list_row_hash);
rowHash.setText(WalletUtils.formatHash(null, header.getHashAsString(), 8, 0, ' '));
final int transactionChildCount = row.getChildCount() - ROW_BASE_CHILD_COUNT;
int iTransactionView = 0;
if (transactions != null) {
final String precision =
prefs.getString(
Constants.PREFS_KEY_BTC_PRECISION, Constants.PREFS_DEFAULT_BTC_PRECISION);
final int btcPrecision = precision.charAt(0) - '0';
final int btcShift = precision.length() == 3 ? precision.charAt(2) - '0' : 0;
transactionsAdapter.setPrecision(btcPrecision, btcShift);
for (final Transaction tx : transactions) {
if (tx.getAppearsInHashes().containsKey(header.getHash())) {
final View view;
if (iTransactionView < transactionChildCount) {
view = row.getChildAt(ROW_INSERT_INDEX + iTransactionView);
} else {
view = getLayoutInflater(null).inflate(R.layout.transaction_row_oneline, null);
row.addView(view, ROW_INSERT_INDEX + iTransactionView);
}
transactionsAdapter.bindView(view, tx);
iTransactionView++;
}
}
}
final int leftoverTransactionViews = transactionChildCount - iTransactionView;
if (leftoverTransactionViews > 0)
row.removeViews(ROW_INSERT_INDEX + iTransactionView, leftoverTransactionViews);
return row;
}
private synchronized boolean add(Block block, boolean tryConnecting)
throws BlockStoreException, VerificationException, ScriptException {
if (System.currentTimeMillis() - statsLastTime > 1000) {
// More than a second passed since last stats logging.
log.info("{} blocks per second", statsBlocksAdded);
statsLastTime = System.currentTimeMillis();
statsBlocksAdded = 0;
}
// We check only the chain head for double adds here to avoid potentially expensive block chain
// misses.
if (block.equals(chainHead.getHeader())) {
// Duplicate add of the block at the top of the chain, can be a natural artifact of the
// download process.
return true;
}
// Prove the block is internally valid: hash is lower than target, merkle root is correct and so
// on.
try {
block.verify();
} catch (VerificationException e) {
log.error("Failed to verify block:", e);
log.error(block.toString());
throw e;
}
// Try linking it to a place in the currently known blocks.
StoredBlock storedPrev = blockStore.get(block.getPrevBlockHash());
if (storedPrev == null) {
// We can't find the previous block. Probably we are still in the process of downloading the
// chain and a
// block was solved whilst we were doing it. We put it to one side and try to connect it later
// when we
// have more blocks.
log.warn("Block does not connect: {}", block.getHashAsString());
unconnectedBlocks.add(block);
return false;
} else {
// It connects to somewhere on the chain. Not necessarily the top of the best known chain.
//
// Create a new StoredBlock from this block. It will throw away the transaction data so when
// block goes
// out of scope we will reclaim the used memory.
StoredBlock newStoredBlock = storedPrev.build(block);
checkDifficultyTransitions(storedPrev, newStoredBlock);
blockStore.put(newStoredBlock);
// block.transactions may be null here if we received only a header and not a full block. This
// does not
// happen currently but might in future if getheaders is implemented.
connectBlock(newStoredBlock, storedPrev, block.transactions);
}
if (tryConnecting) tryConnectingUnconnected();
statsBlocksAdded++;
return true;
}
/**
* Returns the set of contiguous blocks between 'higher' and 'lower'. Higher is included, lower is
* not.
*/
private List<StoredBlock> getPartialChain(StoredBlock higher, StoredBlock lower)
throws BlockStoreException {
assert higher.getHeight() > lower.getHeight();
LinkedList<StoredBlock> results = new LinkedList<StoredBlock>();
StoredBlock cursor = higher;
while (true) {
results.add(cursor);
cursor = cursor.getPrev(blockStore);
assert cursor != null : "Ran off the end of the chain";
if (cursor.equals(lower)) break;
}
return results;
}
public synchronized void put(StoredBlock block) throws BlockStoreException {
try {
Sha256Hash hash = block.getHeader().getHash();
assert blockMap.get(hash) == null : "Attempt to insert duplicate";
// Append to the end of the file. The other fields in StoredBlock will be recalculated when
// it's reloaded.
byte[] bytes = block.getHeader().bitcoinSerialize();
stream.write(bytes);
stream.flush();
blockMap.put(hash, block);
} catch (IOException e) {
throw new BlockStoreException(e);
}
}
public synchronized void setChainHead(StoredBlock chainHead) throws BlockStoreException {
try {
this.chainHead = chainHead.getHeader().getHash();
// Write out new hash to the first 32 bytes of the file past one (first byte is version
// number).
stream.getChannel().write(ByteBuffer.wrap(this.chainHead.getBytes()), 1);
} catch (IOException e) {
throw new BlockStoreException(e);
}
}
/**
* This is broken for blocks that do not pass BIP30, so all BIP30-failing blocks which are allowed
* to fail BIP30 must be checkpointed.
*/
@Override
protected void disconnectTransactions(StoredBlock oldBlock)
throws PrunedException, BlockStoreException {
checkState(lock.isHeldByCurrentThread());
blockStore.beginDatabaseBatchWrite();
try {
StoredUndoableBlock undoBlock = blockStore.getUndoBlock(oldBlock.getHeader().getHash());
if (undoBlock == null) throw new PrunedException(oldBlock.getHeader().getHash());
TransactionOutputChanges txOutChanges = undoBlock.getTxOutChanges();
for (StoredTransactionOutput out : txOutChanges.txOutsSpent)
blockStore.addUnspentTransactionOutput(out);
for (StoredTransactionOutput out : txOutChanges.txOutsCreated)
blockStore.removeUnspentTransactionOutput(out);
} catch (PrunedException e) {
blockStore.abortDatabaseBatchWrite();
throw e;
} catch (BlockStoreException e) {
blockStore.abortDatabaseBatchWrite();
throw e;
}
}
/**
* Constructs a BlockChain connected to the given wallet and store. To obtain a {@link Wallet} you
* can construct one from scratch, or you can deserialize a saved wallet from disk using {@link
* Wallet#loadFromFile(java.io.File)}
*
* <p>For the store you can use a {@link MemoryBlockStore} if you don't care about saving the
* downloaded data, or a {@link BoundedOverheadBlockStore} if you'd like to ensure fast startup
* the next time you run the program.
*/
public BlockChain(NetworkParameters params, Wallet wallet, BlockStore blockStore) {
try {
this.blockStore = blockStore;
chainHead = blockStore.getChainHead();
log.info("chain head is:\n{}", chainHead.getHeader());
} catch (BlockStoreException e) {
throw new RuntimeException(e);
}
this.params = params;
this.wallet = wallet;
}
private void connectBlock(
StoredBlock newStoredBlock, StoredBlock storedPrev, List<Transaction> newTransactions)
throws BlockStoreException, VerificationException {
if (storedPrev.equals(chainHead)) {
// This block connects to the best known block, it is a normal continuation of the system.
setChainHead(newStoredBlock);
log.trace("Chain is now {} blocks high", chainHead.getHeight());
if (newTransactions != null)
sendTransactionsToWallet(newStoredBlock, NewBlockType.BEST_CHAIN, newTransactions);
} else {
// This block connects to somewhere other than the top of the best known chain. We treat these
// differently.
//
// Note that we send the transactions to the wallet FIRST, even if we're about to re-organize
// this block
// to become the new best chain head. This simplifies handling of the re-org in the Wallet
// class.
boolean haveNewBestChain = newStoredBlock.moreWorkThan(chainHead);
if (haveNewBestChain) {
log.info("Block is causing a re-organize");
} else {
StoredBlock splitPoint = findSplit(newStoredBlock, chainHead);
String splitPointHash = splitPoint != null ? splitPoint.getHeader().getHashAsString() : "?";
log.info(
"Block forks the chain at {}, but it did not cause a reorganize:\n{}",
splitPointHash,
newStoredBlock);
}
// We may not have any transactions if we received only a header. That never happens today but
// will in
// future when getheaders is used as an optimization.
if (newTransactions != null) {
sendTransactionsToWallet(newStoredBlock, NewBlockType.SIDE_CHAIN, newTransactions);
}
if (haveNewBestChain) handleNewBestChain(newStoredBlock);
}
}
/**
* Called as part of connecting a block when the new block results in a different chain having
* higher total work.
*/
private void handleNewBestChain(StoredBlock newChainHead)
throws BlockStoreException, VerificationException {
// This chain has overtaken the one we currently believe is best. Reorganize is required.
//
// Firstly, calculate the block at which the chain diverged. We only need to examine the
// chain from beyond this block to find differences.
StoredBlock splitPoint = findSplit(newChainHead, chainHead);
log.info("Re-organize after split at height {}", splitPoint.getHeight());
log.info("Old chain head: {}", chainHead.getHeader().getHashAsString());
log.info("New chain head: {}", newChainHead.getHeader().getHashAsString());
log.info("Split at block: {}", splitPoint.getHeader().getHashAsString());
// Then build a list of all blocks in the old part of the chain and the new part.
List<StoredBlock> oldBlocks = getPartialChain(chainHead, splitPoint);
List<StoredBlock> newBlocks = getPartialChain(newChainHead, splitPoint);
// Now inform the wallet. This is necessary so the set of currently active transactions (that we
// can spend)
// can be updated to take into account the re-organize. We might also have received new coins we
// didn't have
// before and our previous spends might have been undone.
wallet.reorganize(oldBlocks, newBlocks);
// Update the pointer to the best known block.
setChainHead(newChainHead);
}
private void createNewStore(NetworkParameters params, File file) throws BlockStoreException {
// Create a new block store if the file wasn't found or anything went wrong whilst reading.
blockMap.clear();
try {
stream = new FileOutputStream(file, false); // Do not append, create fresh.
stream.write(1); // Version.
} catch (IOException e1) {
// We could not load a block store nor could we create a new one!
throw new BlockStoreException(e1);
}
try {
// Set up the genesis block. When we start out fresh, it is by definition the top of the
// chain.
Block genesis = params.genesisBlock.cloneAsHeader();
StoredBlock storedGenesis = new StoredBlock(genesis, genesis.getWork(), 0);
this.chainHead = storedGenesis.getHeader().getHash();
stream.write(this.chainHead.getBytes());
put(storedGenesis);
} catch (VerificationException e1) {
throw new RuntimeException(e1); // Cannot happen.
} catch (IOException e) {
throw new BlockStoreException(e);
}
}
/**
* Locates the point in the chain at which newStoredBlock and chainHead diverge. Returns null if
* no split point was found (ie they are part of the same chain).
*/
private StoredBlock findSplit(StoredBlock newChainHead, StoredBlock chainHead)
throws BlockStoreException {
StoredBlock currentChainCursor = chainHead;
StoredBlock newChainCursor = newChainHead;
// Loop until we find the block both chains have in common. Example:
//
// A -> B -> C -> D
// \--> E -> F -> G
//
// findSplit will return block B. chainHead = D and newChainHead = G.
while (!currentChainCursor.equals(newChainCursor)) {
if (currentChainCursor.getHeight() > newChainCursor.getHeight()) {
currentChainCursor = currentChainCursor.getPrev(blockStore);
assert currentChainCursor != null : "Attempt to follow an orphan chain";
} else {
newChainCursor = newChainCursor.getPrev(blockStore);
assert newChainCursor != null : "Attempt to follow an orphan chain";
}
}
return currentChainCursor;
}
@Test
public void testStorage() throws Exception {
File temp = File.createTempFile("bitcoinj-test", null, null);
System.out.println(temp.getAbsolutePath());
temp.deleteOnExit();
NetworkParameters params = NetworkParameters.unitTests();
Address to = new ECKey().toAddress(params);
BoundedOverheadBlockStore store = new BoundedOverheadBlockStore(params, temp);
// Check the first block in a new store is the genesis block.
StoredBlock genesis = store.getChainHead();
assertEquals(params.genesisBlock, genesis.getHeader());
// Build a new block.
StoredBlock b1 = genesis.build(genesis.getHeader().createNextBlock(to).cloneAsHeader());
store.put(b1);
store.setChainHead(b1);
// Check we can get it back out again if we rebuild the store object.
store = new BoundedOverheadBlockStore(params, temp);
StoredBlock b2 = store.get(b1.getHeader().getHash());
assertEquals(b1, b2);
// Check the chain head was stored correctly also.
assertEquals(b1, store.getChainHead());
}
@Override
/** Used during reorgs to connect a block previously on a fork */
protected synchronized TransactionOutputChanges connectTransactions(StoredBlock newBlock)
throws VerificationException, BlockStoreException, PrunedException {
checkState(lock.isHeldByCurrentThread());
if (!params.passesCheckpoint(newBlock.getHeight(), newBlock.getHeader().getHash()))
throw new VerificationException("Block failed checkpoint lockin at " + newBlock.getHeight());
blockStore.beginDatabaseBatchWrite();
StoredUndoableBlock block = blockStore.getUndoBlock(newBlock.getHeader().getHash());
if (block == null) {
// We're trying to re-org too deep and the data needed has been deleted.
blockStore.abortDatabaseBatchWrite();
throw new PrunedException(newBlock.getHeader().getHash());
}
TransactionOutputChanges txOutChanges;
try {
List<Transaction> transactions = block.getTransactions();
if (transactions != null) {
LinkedList<StoredTransactionOutput> txOutsSpent = new LinkedList<StoredTransactionOutput>();
LinkedList<StoredTransactionOutput> txOutsCreated =
new LinkedList<StoredTransactionOutput>();
long sigOps = 0;
final boolean enforcePayToScriptHash =
newBlock.getHeader().getTimeSeconds() >= NetworkParameters.BIP16_ENFORCE_TIME;
if (!params.isCheckpoint(newBlock.getHeight())) {
for (Transaction tx : transactions) {
Sha256Hash hash = tx.getHash();
if (blockStore.hasUnspentOutputs(hash, tx.getOutputs().size()))
throw new VerificationException("Block failed BIP30 test!");
}
}
Coin totalFees = Coin.ZERO;
Coin coinbaseValue = null;
if (scriptVerificationExecutor.isShutdown())
scriptVerificationExecutor =
Executors.newFixedThreadPool(Runtime.getRuntime().availableProcessors());
List<Future<VerificationException>> listScriptVerificationResults =
new ArrayList<Future<VerificationException>>(transactions.size());
for (final Transaction tx : transactions) {
boolean isCoinBase = tx.isCoinBase();
Coin valueIn = Coin.ZERO;
Coin valueOut = Coin.ZERO;
final List<Script> prevOutScripts = new LinkedList<Script>();
if (!isCoinBase) {
for (int index = 0; index < tx.getInputs().size(); index++) {
final TransactionInput in = tx.getInputs().get(index);
final StoredTransactionOutput prevOut =
blockStore.getTransactionOutput(
in.getOutpoint().getHash(), in.getOutpoint().getIndex());
if (prevOut == null)
throw new VerificationException(
"Attempted spend of a non-existent or already spent output!");
if (newBlock.getHeight() - prevOut.getHeight() < params.getSpendableCoinbaseDepth())
throw new VerificationException(
"Tried to spend coinbase at depth "
+ (newBlock.getHeight() - prevOut.getHeight()));
valueIn = valueIn.add(prevOut.getValue());
if (enforcePayToScriptHash) {
Script script = new Script(prevOut.getScriptBytes());
if (script.isPayToScriptHash())
sigOps += Script.getP2SHSigOpCount(in.getScriptBytes());
if (sigOps > Block.MAX_BLOCK_SIGOPS)
throw new VerificationException("Too many P2SH SigOps in block");
}
prevOutScripts.add(new Script(prevOut.getScriptBytes()));
blockStore.removeUnspentTransactionOutput(prevOut);
txOutsSpent.add(prevOut);
}
}
Sha256Hash hash = tx.getHash();
for (TransactionOutput out : tx.getOutputs()) {
valueOut = valueOut.add(out.getValue());
StoredTransactionOutput newOut =
new StoredTransactionOutput(
hash,
out.getIndex(),
out.getValue(),
newBlock.getHeight(),
isCoinBase,
out.getScriptBytes());
blockStore.addUnspentTransactionOutput(newOut);
txOutsCreated.add(newOut);
}
// All values were already checked for being non-negative (as it is verified in
// Transaction.verify())
// but we check again here just for defence in depth. Transactions with zero output value
// are OK.
if (valueOut.signum() < 0 || valueOut.compareTo(NetworkParameters.MAX_MONEY) > 0)
throw new VerificationException("Transaction output value out of range");
if (isCoinBase) {
coinbaseValue = valueOut;
} else {
if (valueIn.compareTo(valueOut) < 0
|| valueIn.compareTo(NetworkParameters.MAX_MONEY) > 0)
throw new VerificationException("Transaction input value out of range");
totalFees = totalFees.add(valueIn.subtract(valueOut));
}
if (!isCoinBase) {
// Because correctlySpends modifies transactions, this must come after we are done with
// tx
FutureTask<VerificationException> future =
new FutureTask<VerificationException>(
new Verifier(tx, prevOutScripts, enforcePayToScriptHash));
scriptVerificationExecutor.execute(future);
listScriptVerificationResults.add(future);
}
}
if (totalFees.compareTo(NetworkParameters.MAX_MONEY) > 0
|| newBlock
.getHeader()
.getBlockInflation(newBlock.getHeight())
.add(totalFees)
.compareTo(coinbaseValue)
< 0) throw new VerificationException("Transaction fees out of range");
txOutChanges = new TransactionOutputChanges(txOutsCreated, txOutsSpent);
for (Future<VerificationException> future : listScriptVerificationResults) {
VerificationException e;
try {
e = future.get();
} catch (InterruptedException thrownE) {
throw new RuntimeException(thrownE); // Shouldn't happen
} catch (ExecutionException thrownE) {
log.error("Script.correctlySpends threw a non-normal exception: " + thrownE.getCause());
throw new VerificationException(
"Bug in Script.correctlySpends, likely script malformed in some new and interesting way.",
thrownE);
}
if (e != null) throw e;
}
} else {
txOutChanges = block.getTxOutChanges();
if (!params.isCheckpoint(newBlock.getHeight()))
for (StoredTransactionOutput out : txOutChanges.txOutsCreated) {
Sha256Hash hash = out.getHash();
if (blockStore.getTransactionOutput(hash, out.getIndex()) != null)
throw new VerificationException("Block failed BIP30 test!");
}
for (StoredTransactionOutput out : txOutChanges.txOutsCreated)
blockStore.addUnspentTransactionOutput(out);
for (StoredTransactionOutput out : txOutChanges.txOutsSpent)
blockStore.removeUnspentTransactionOutput(out);
}
} catch (VerificationException e) {
scriptVerificationExecutor.shutdownNow();
blockStore.abortDatabaseBatchWrite();
throw e;
} catch (BlockStoreException e) {
scriptVerificationExecutor.shutdownNow();
blockStore.abortDatabaseBatchWrite();
throw e;
}
return txOutChanges;
}
public static void main(String[] args) throws Exception {
BriefLogFormatter.init();
// Sorted map of UNIX time of block to StoredBlock object.
final TreeMap<Integer, StoredBlock> checkpoints = new TreeMap<Integer, StoredBlock>();
// Configure bitcoinj to fetch only headers, not save them to disk, connect to a local fully
// synced/validated
// node and to save block headers that are on interval boundaries, as long as they are <1 month
// old.
final BlockStore store = new MemoryBlockStore(PARAMS);
final BlockChain chain = new BlockChain(PARAMS, store);
final PeerGroup peerGroup = new PeerGroup(PARAMS, chain);
peerGroup.addAddress(InetAddress.getLocalHost());
// peerGroup.addAddress(InetAddress.getByName("69.164.198.161"));
long now = new Date().getTime() / 1000;
peerGroup.setFastCatchupTimeSecs(now);
final long oneMonthAgo = now - (86400 * 2);
chain.addListener(
new AbstractBlockChainListener() {
@Override
public void notifyNewBestBlock(StoredBlock block) throws VerificationException {
int height = block.getHeight();
if (height % CoinDefinition.getIntervalCheckpoints() == 0
&& block.getHeader().getTimeSeconds() <= oneMonthAgo) {
// if (height % PARAMS.getInterval() == 0 &&
// block.getHeader().getTimeSeconds() <= oneMonthAgo) {
System.out.println(
String.format(
"Checkpointing block %s at height %d",
block.getHeader().getHash(), block.getHeight()));
checkpoints.put(height, block);
}
}
},
Threading.SAME_THREAD);
peerGroup.startAndWait();
peerGroup.downloadBlockChain();
checkState(checkpoints.size() > 0);
// Write checkpoint data out.
final FileOutputStream fileOutputStream = new FileOutputStream(CHECKPOINTS_FILE, false);
MessageDigest digest = MessageDigest.getInstance("SHA-256");
final DigestOutputStream digestOutputStream = new DigestOutputStream(fileOutputStream, digest);
digestOutputStream.on(false);
final DataOutputStream dataOutputStream = new DataOutputStream(digestOutputStream);
dataOutputStream.writeBytes("CHECKPOINTS 1");
dataOutputStream.writeInt(0); // Number of signatures to read. Do this later.
digestOutputStream.on(true);
dataOutputStream.writeInt(checkpoints.size());
ByteBuffer buffer = ByteBuffer.allocate(StoredBlock.COMPACT_SERIALIZED_SIZE);
for (StoredBlock block : checkpoints.values()) {
block.serializeCompact(buffer);
dataOutputStream.write(buffer.array());
buffer.position(0);
}
dataOutputStream.close();
Sha256Hash checkpointsHash = new Sha256Hash(digest.digest());
System.out.println("Hash of checkpoints data is " + checkpointsHash);
digestOutputStream.close();
fileOutputStream.close();
peerGroup.stopAndWait();
store.close();
// Sanity check the created file.
CheckpointManager manager =
new CheckpointManager(PARAMS, new FileInputStream(CHECKPOINTS_FILE));
checkState(manager.numCheckpoints() == checkpoints.size());
/*if (PARAMS.getId() == NetworkParameters.ID_MAINNET) {
StoredBlock test = manager.getCheckpointBefore(1390500000); // Thu Jan 23 19:00:00 CET 2014
checkState(test.getHeight() == 280224);
checkState(test.getHeader().getHashAsString()
.equals("00000000000000000b5d59a15f831e1c45cb688a4db6b0a60054d49a9997fa34"));
} else if (PARAMS.getId() == NetworkParameters.ID_TESTNET) {
StoredBlock test = manager.getCheckpointBefore(1390500000); // Thu Jan 23 19:00:00 CET 2014
checkState(test.getHeight() == 167328);
checkState(test.getHeader().getHashAsString()
.equals("0000000000035ae7d5025c2538067fe7adb1cf5d5d9c31b024137d9090ed13a9"));
}*/
System.out.println("Checkpoints written to '" + CHECKPOINTS_FILE.getCanonicalPath() + "'.");
}
private void load(File file) throws IOException, BlockStoreException {
log.info("Reading block store from {}", file);
InputStream input = null;
try {
input = new BufferedInputStream(new FileInputStream(file));
// Read a version byte.
int version = input.read();
if (version == -1) {
// No such file or the file was empty.
throw new FileNotFoundException(file.getName() + " does not exist or is empty");
}
if (version != 1) {
throw new BlockStoreException("Bad version number: " + version);
}
// Chain head pointer is the first thing in the file.
byte[] chainHeadHash = new byte[32];
if (input.read(chainHeadHash) < chainHeadHash.length)
throw new BlockStoreException("Truncated block store: cannot read chain head hash");
this.chainHead = new Sha256Hash(chainHeadHash);
log.info("Read chain head from disk: {}", this.chainHead);
long now = System.currentTimeMillis();
// Rest of file is raw block headers.
byte[] headerBytes = new byte[Block.HEADER_SIZE];
try {
while (true) {
// Read a block from disk.
if (input.read(headerBytes) < 80) {
// End of file.
break;
}
// Parse it.
Block b = new Block(params, headerBytes);
// Look up the previous block it connects to.
StoredBlock prev = get(b.getPrevBlockHash());
StoredBlock s;
if (prev == null) {
// First block in the stored chain has to be treated specially.
if (b.equals(params.genesisBlock)) {
s =
new StoredBlock(
params.genesisBlock.cloneAsHeader(), params.genesisBlock.getWork(), 0);
} else {
throw new BlockStoreException(
"Could not connect "
+ b.getHash().toString()
+ " to "
+ b.getPrevBlockHash().toString());
}
} else {
// Don't try to verify the genesis block to avoid upsetting the unit tests.
b.verifyHeader();
// Calculate its height and total chain work.
s = prev.build(b);
}
// Save in memory.
blockMap.put(b.getHash(), s);
}
} catch (ProtocolException e) {
// Corrupted file.
throw new BlockStoreException(e);
} catch (VerificationException e) {
// Should not be able to happen unless the file contains bad blocks.
throw new BlockStoreException(e);
}
long elapsed = System.currentTimeMillis() - now;
log.info("Block chain read complete in {}ms", elapsed);
} finally {
if (input != null) input.close();
}
}
/** Throws an exception if the blocks difficulty is not correct. */
private void checkDifficultyTransitions(StoredBlock storedPrev, StoredBlock storedNext)
throws BlockStoreException, VerificationException {
Block prev = storedPrev.getHeader();
Block next = storedNext.getHeader();
// Is this supposed to be a difficulty transition point?
if ((storedPrev.getHeight() + 1) % params.interval != 0) {
// No ... so check the difficulty didn't actually change.
if (next.getDifficultyTarget() != prev.getDifficultyTarget())
throw new VerificationException(
"Unexpected change in difficulty at height "
+ storedPrev.getHeight()
+ ": "
+ Long.toHexString(next.getDifficultyTarget())
+ " vs "
+ Long.toHexString(prev.getDifficultyTarget()));
return;
}
// We need to find a block far back in the chain. It's OK that this is expensive because it only
// occurs every
// two weeks after the initial block chain download.
long now = System.currentTimeMillis();
StoredBlock cursor = blockStore.get(prev.getHash());
for (int i = 0; i < params.interval - 1; i++) {
if (cursor == null) {
// This should never happen. If it does, it means we are following an incorrect or busted
// chain.
throw new VerificationException(
"Difficulty transition point but we did not find a way back to the genesis block.");
}
cursor = blockStore.get(cursor.getHeader().getPrevBlockHash());
}
log.info("Difficulty transition traversal took {}msec", System.currentTimeMillis() - now);
Block blockIntervalAgo = cursor.getHeader();
int timespan = (int) (prev.getTime() - blockIntervalAgo.getTime());
// Limit the adjustment step.
if (timespan < params.targetTimespan / 4) timespan = params.targetTimespan / 4;
if (timespan > params.targetTimespan * 4) timespan = params.targetTimespan * 4;
BigInteger newDifficulty = Utils.decodeCompactBits(blockIntervalAgo.getDifficultyTarget());
newDifficulty = newDifficulty.multiply(BigInteger.valueOf(timespan));
newDifficulty = newDifficulty.divide(BigInteger.valueOf(params.targetTimespan));
if (newDifficulty.compareTo(params.proofOfWorkLimit) > 0) {
log.warn("Difficulty hit proof of work limit: {}", newDifficulty.toString(16));
newDifficulty = params.proofOfWorkLimit;
}
int accuracyBytes = (int) (next.getDifficultyTarget() >>> 24) - 3;
BigInteger receivedDifficulty = next.getDifficultyTargetAsInteger();
// The calculated difficulty is to a higher precision than received, so reduce here.
BigInteger mask = BigInteger.valueOf(0xFFFFFFL).shiftLeft(accuracyBytes * 8);
newDifficulty = newDifficulty.and(mask);
if (newDifficulty.compareTo(receivedDifficulty) != 0)
throw new VerificationException(
"Network provided difficulty bits do not match what was calculated: "
+ receivedDifficulty.toString(16)
+ " vs "
+ newDifficulty.toString(16));
}