sbt.internal.BootServerSocket Maven / Gradle / Ivy
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/*
* sbt
* Copyright 2023, Scala center
* Copyright 2011 - 2022, Lightbend, Inc.
* Copyright 2008 - 2010, Mark Harrah
* Licensed under Apache License 2.0 (see LICENSE)
*/
package sbt.internal;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.UnsupportedEncodingException;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.net.Socket;
import java.net.ServerSocket;
import java.net.SocketException;
import java.net.SocketTimeoutException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.Set;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;
import java.util.concurrent.LinkedBlockingQueue;
import java.util.concurrent.RejectedExecutionException;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.concurrent.atomic.AtomicInteger;
import net.openhft.hashing.LongHashFunction;
import org.scalasbt.ipcsocket.UnixDomainServerSocket;
import org.scalasbt.ipcsocket.Win32NamedPipeServerSocket;
import org.scalasbt.ipcsocket.Win32NamedPipeSocket;
import org.scalasbt.ipcsocket.Win32SecurityLevel;
import sbt.internal.util.Terminal;
import xsbti.AppConfiguration;
/**
* A BootServerSocket is used for remote clients to connect to sbt for io while sbt is still loading
* the build. There are two scenarios in which this functionality is needed:
*
* 1. client a starts an sbt server and then client b tries to connect to the server before the
* server has loaded. Presently, client b will try to start a new server even though there is one
* booting. This can cause a java process leak because the second server launched by client b is
* unable to create a server because there is an existing portfile by the time it starts up.
*
*
2. a remote client initiates a reboot command. Reboot causes sbt to shutdown the server which
* makes the client disconnect. Since sbt does not start the server until the project has
* successfully loaded, there is no way for the client to see the output of the server. This is
* particularly problematic if loading fails because the server will be stuck waiting for input that
* will not be forthcoming.
*
*
To address these issues, the BootServerSocket can be used to immediately create a server
* socket before sbt even starts loading the build. It works by creating a local socket either in
* project/target/SOCK_NAME or a windows named pipe with name SOCK_NAME where SOCK_NAME is computed
* as the hash of the project's base directory (for disambiguation in the windows case). If the
* server can't create a server socket because there is already one running, it either prompts the
* user if they want to start a new server even if there is already one running if there is a
* console available or exits with the status code 2 which indicates that there is another sbt
* process starting up.
*
*
Once the server socket is created, it listens for new client connections. When a client
* connects, the server will forward its input and output to the client via Terminal.setBootStreams
* which updates the Terminal.proxyOutputStream to forward all bytes written to the
* BootServerSocket's outputStream which in turn writes the output to each of the connected clients.
* Input is handed similarly.
*
*
When the server finishes loading, it closes the boot server socket.
*
*
BootServerSocket is implemented in java so that it can be classloaded as quickly as possible.
*/
public class BootServerSocket implements AutoCloseable {
private ServerSocket serverSocket = null;
private final AtomicBoolean closed = new AtomicBoolean(false);
private final AtomicBoolean running = new AtomicBoolean(false);
private final AtomicInteger threadId = new AtomicInteger(1);
private final Future acceptFuture;
private final ExecutorService service =
Executors.newCachedThreadPool(
r -> new Thread(r, "boot-server-socket-thread-" + threadId.getAndIncrement()));
private final Set clientSockets = ConcurrentHashMap.newKeySet();
private final Object lock = new Object();
private final LinkedBlockingQueue clientSocketReads = new LinkedBlockingQueue<>();
private final Path socketFile;
private final AtomicBoolean needInput = new AtomicBoolean(false);
private class ClientSocket implements AutoCloseable {
final Socket socket;
final AtomicBoolean alive = new AtomicBoolean(true);
final Future future;
private final LinkedBlockingQueue bytes = new LinkedBlockingQueue();
private final AtomicBoolean closed = new AtomicBoolean(false);
@SuppressWarnings("deprecation")
ClientSocket(final Socket socket) {
this.socket = socket;
clientSockets.add(this);
Future f = null;
try {
f =
service.submit(
() -> {
try {
Terminal.console()
.getLines()
.foreach(
l -> {
try {
write((l + System.lineSeparator()).getBytes("UTF-8"));
} catch (final IOException e) {
}
return 0;
});
final InputStream inputStream = socket.getInputStream();
while (alive.get()) {
try {
synchronized (needInput) {
while (!needInput.get() && alive.get()) needInput.wait();
}
if (alive.get()) {
socket.getOutputStream().write(5);
int b = inputStream.read();
if (b != -1) {
bytes.put(b);
clientSocketReads.put(ClientSocket.this);
} else {
alive.set(false);
}
}
} catch (IOException e) {
alive.set(false);
}
}
} catch (final Exception ex) {
}
});
} catch (final RejectedExecutionException e) {
alive.set(false);
}
future = f;
}
private void write(final int i) {
try {
if (alive.get()) socket.getOutputStream().write(i);
} catch (final IOException e) {
alive.set(false);
close();
}
}
private void write(final byte[] b) {
try {
if (alive.get()) socket.getOutputStream().write(b);
} catch (final IOException e) {
alive.set(false);
close();
}
}
private void write(final byte[] b, final int offset, final int len) {
try {
if (alive.get()) socket.getOutputStream().write(b, offset, len);
} catch (final IOException e) {
alive.set(false);
close();
}
}
private void flush() {
try {
socket.getOutputStream().flush();
} catch (final IOException e) {
alive.set(false);
close();
}
}
@SuppressWarnings("EmptyCatchBlock")
@Override
public void close() {
if (closed.compareAndSet(false, true)) {
if (alive.get()) {
write(2);
bytes.forEach(this::write);
bytes.clear();
write(3);
flush();
}
alive.set(false);
if (future != null) future.cancel(true);
try {
socket.getOutputStream().close();
socket.getInputStream().close();
// Windows is very slow to close the socket for whatever reason
// We close the server socket anyway, so this should die then.
if (!System.getProperty("os.name", "").toLowerCase().startsWith("win")) socket.close();
} catch (final IOException e) {
}
clientSockets.remove(this);
}
}
}
private final Object writeLock = new Object();
public InputStream inputStream() {
return inputStream;
}
private final InputStream inputStream =
new InputStream() {
@Override
public int read() {
if (clientSockets.isEmpty()) return Terminal.NO_BOOT_CLIENTS_CONNECTED();
try {
synchronized (needInput) {
needInput.set(true);
needInput.notifyAll();
}
ClientSocket clientSocket = clientSocketReads.take();
return clientSocket.bytes.take();
} catch (final InterruptedException e) {
return -1;
} finally {
synchronized (needInput) {
needInput.set(false);
}
}
}
};
private final OutputStream outputStream =
new OutputStream() {
@Override
public void write(final int b) {
synchronized (lock) {
clientSockets.forEach(cs -> cs.write(b));
}
}
@Override
public void write(final byte[] b) {
write(b, 0, b.length);
}
@Override
public void write(final byte[] b, final int offset, final int len) {
synchronized (lock) {
clientSockets.forEach(cs -> cs.write(b, offset, len));
}
}
@Override
public void flush() {
synchronized (lock) {
clientSockets.forEach(cs -> cs.flush());
}
}
};
public OutputStream outputStream() {
return outputStream;
}
private final Runnable acceptRunnable =
() -> {
try {
serverSocket.setSoTimeout(5000);
while (running.get()) {
try {
ClientSocket clientSocket = new ClientSocket(serverSocket.accept());
} catch (final SocketTimeoutException e) {
} catch (final IOException e) {
running.set(false);
}
}
} catch (final SocketException e) {
}
};
public BootServerSocket(final AppConfiguration configuration)
throws ServerAlreadyBootingException, IOException {
final Path base = configuration.baseDirectory().toPath().toRealPath();
if (!isWindows) {
final String actualSocketLocation = socketLocation(base);
final Path target = Paths.get(actualSocketLocation).getParent();
if (!Files.isDirectory(target)) Files.createDirectories(target);
socketFile = Paths.get(actualSocketLocation);
} else {
socketFile = null;
}
serverSocket = newSocket(socketLocation(base));
if (serverSocket != null) {
running.set(true);
acceptFuture = service.submit(acceptRunnable);
} else {
closed.set(true);
acceptFuture = null;
}
}
public static String socketLocation(final Path base)
throws UnsupportedEncodingException, IOException {
final Path target = base.resolve("project").resolve("target");
long hash = LongHashFunction.farmNa().hashBytes(target.toString().getBytes("UTF-8"));
if (isWindows) {
return "sbt-load" + hash;
} else {
final String alternativeSocketLocation =
System.getenv().getOrDefault("XDG_RUNTIME_DIR", System.getProperty("java.io.tmpdir"));
final Path alternativeSocketLocationRoot =
Paths.get(alternativeSocketLocation).resolve(".sbt");
final Path locationForSocket = alternativeSocketLocationRoot.resolve("sbt-socket" + hash);
final Path pathForSocket = locationForSocket.resolve("sbt-load.sock");
return pathForSocket.toString();
}
}
@SuppressWarnings("EmptyCatchBlock")
@Override
public void close() {
if (closed.compareAndSet(false, true)) {
// avoid concurrent modification exception
clientSockets.forEach(ClientSocket::close);
if (acceptFuture != null) acceptFuture.cancel(true);
service.shutdownNow();
try {
if (serverSocket != null) serverSocket.close();
} catch (final IOException e) {
}
try {
if (socketFile != null) Files.deleteIfExists(socketFile);
} catch (final IOException e) {
}
}
}
static final boolean isWindows =
System.getProperty("os.name", "").toLowerCase().startsWith("win");
static ServerSocket newSocket(final String sock) throws ServerAlreadyBootingException {
ServerSocket socket = null;
String name = socketName(sock);
boolean jni = requiresJNI() || System.getProperty("sbt.ipcsocket.jni", "false").equals("true");
try {
if (!isWindows) Files.deleteIfExists(Paths.get(sock));
socket =
isWindows
? new Win32NamedPipeServerSocket(name, jni, Win32SecurityLevel.OWNER_DACL)
: new UnixDomainServerSocket(name, jni);
return socket;
} catch (final IOException e) {
throw new ServerAlreadyBootingException(e);
}
}
public static Boolean requiresJNI() {
final boolean isMac = System.getProperty("os.name").toLowerCase().startsWith("mac");
return isMac && !System.getProperty("os.arch", "").equals("x86_64");
}
private static String socketName(String sock) {
return isWindows ? "\\\\.\\pipe\\" + sock : sock;
}
}