public static void main(String[] args) throws Throwable {
final ReentrantLock lock = new ReentrantLock();
lock.lock();
final ReentrantReadWriteLock rwlock = new ReentrantReadWriteLock();
final ReentrantReadWriteLock.ReadLock readLock = rwlock.readLock();
final ReentrantReadWriteLock.WriteLock writeLock = rwlock.writeLock();
rwlock.writeLock().lock();
final BlockingQueue<Object> q = new LinkedBlockingQueue<Object>();
final Semaphore fairSem = new Semaphore(0, true);
final Semaphore unfairSem = new Semaphore(0, false);
// final int threads =
// rnd.nextInt(Runtime.getRuntime().availableProcessors() + 1) + 1;
final int threads = 3;
// On Linux, this test runs very slowly for some reason,
// so use a smaller number of iterations.
// Solaris can handle 1 << 18.
// On the other hand, jmap is much slower on Solaris...
final int iterations = 1 << 8;
final CyclicBarrier cb = new CyclicBarrier(threads + 1);
for (int i = 0; i < threads; i++)
new Thread() {
public void run() {
try {
final Random rnd = new Random();
for (int j = 0; j < iterations; j++) {
if (j == iterations / 10 || j == iterations - 1) {
cb.await(); // Quiesce
cb.await(); // Resume
}
// int t = rnd.nextInt(2000);
int t = rnd.nextInt(900);
check(!lock.tryLock(t, NANOSECONDS));
check(!readLock.tryLock(t, NANOSECONDS));
check(!writeLock.tryLock(t, NANOSECONDS));
equal(null, q.poll(t, NANOSECONDS));
check(!fairSem.tryAcquire(t, NANOSECONDS));
check(!unfairSem.tryAcquire(t, NANOSECONDS));
}
} catch (Throwable t) {
unexpected(t);
}
}
}.start();
cb.await(); // Quiesce
rendezvousChild(); // Measure
cb.await(); // Resume
cb.await(); // Quiesce
rendezvousChild(); // Measure
cb.await(); // Resume
System.exit(failed);
}
@Override
public void setChainHead(StoredBlock chainHead) throws BlockStoreException {
final MappedByteBuffer buffer = this.buffer;
if (buffer == null) throw new BlockStoreException("Store closed");
lock.lock();
try {
lastChainHead = chainHead;
byte[] headHash = chainHead.getHeader().getHash().getBytes();
buffer.position(8);
buffer.put(headHash);
} finally {
lock.unlock();
}
}
private void initNewStore(NetworkParameters params) throws Exception {
byte[] header;
header = HEADER_MAGIC.getBytes("US-ASCII");
buffer.put(header);
// Insert the genesis block.
lock.lock();
try {
setRingCursor(buffer, FILE_PROLOGUE_BYTES);
} finally {
lock.unlock();
}
Block genesis = params.getGenesisBlock().cloneAsHeader();
StoredBlock storedGenesis = new StoredBlock(genesis, genesis.getWork(), 0);
put(storedGenesis);
setChainHead(storedGenesis);
}
@Override
@Nullable
public StoredBlock get(Sha256Hash hash) throws BlockStoreException {
final MappedByteBuffer buffer = this.buffer;
if (buffer == null) throw new BlockStoreException("Store closed");
lock.lock();
try {
StoredBlock cacheHit = blockCache.get(hash);
if (cacheHit != null) return cacheHit;
if (notFoundCache.get(hash) != null) return null;
// Starting from the current tip of the ring work backwards until we have either found the
// block or
// wrapped around.
int cursor = getRingCursor(buffer);
final int startingPoint = cursor;
final int fileSize = getFileSize();
final byte[] targetHashBytes = hash.getBytes();
byte[] scratch = new byte[32];
do {
cursor -= RECORD_SIZE;
if (cursor < FILE_PROLOGUE_BYTES) {
// We hit the start, so wrap around.
cursor = fileSize - RECORD_SIZE;
}
// Cursor is now at the start of the next record to check, so read the hash and compare it.
buffer.position(cursor);
buffer.get(scratch);
if (Arrays.equals(scratch, targetHashBytes)) {
// Found the target.
StoredBlock storedBlock = StoredBlock.deserializeCompact(params, buffer);
blockCache.put(hash, storedBlock);
return storedBlock;
}
} while (cursor != startingPoint);
// Not found.
notFoundCache.put(hash, notFoundMarker);
return null;
} catch (ProtocolException e) {
throw new RuntimeException(e); // Cannot happen.
} finally {
lock.unlock();
}
}
protected static boolean wasCalledDuringClassLoading() {
if (LOCK.isHeldByCurrentThread()) return true;
LOCK.lock();
try {
StackTrace st = new StackTrace(new Throwable());
int n = st.getDepth();
for (int i = 3; i < n; i++) {
StackTraceElement ste = st.getElement(i);
if ("ClassLoader.java".equals(ste.getFileName())
&& "loadClass".equals(ste.getMethodName())) {
return true;
}
}
return false;
} finally {
LOCK.unlock();
}
}
@Override
public StoredBlock getChainHead() throws BlockStoreException {
final MappedByteBuffer buffer = this.buffer;
if (buffer == null) throw new BlockStoreException("Store closed");
lock.lock();
try {
if (lastChainHead == null) {
byte[] headHash = new byte[32];
buffer.position(8);
buffer.get(headHash);
Sha256Hash hash = new Sha256Hash(headHash);
StoredBlock block = get(hash);
if (block == null)
throw new BlockStoreException(
"Corrupted block store: could not find chain head: " + hash);
lastChainHead = block;
}
return lastChainHead;
} finally {
lock.unlock();
}
}
@Override
public void put(StoredBlock block) throws BlockStoreException {
final MappedByteBuffer buffer = this.buffer;
if (buffer == null) throw new BlockStoreException("Store closed");
lock.lock();
try {
int cursor = getRingCursor(buffer);
if (cursor == getFileSize()) {
// Wrapped around.
cursor = FILE_PROLOGUE_BYTES;
}
buffer.position(cursor);
Sha256Hash hash = block.getHeader().getHash();
notFoundCache.remove(hash);
buffer.put(hash.getBytes());
block.serializeCompact(buffer);
setRingCursor(buffer, buffer.position());
blockCache.put(hash, block);
} finally {
lock.unlock();
}
}