Fixes for IPC

maven-resolver-named-locks-ipc/src/main/java/org/eclipse/aether/named/ipc/IpcClient.java

@@ -75,25 +75,31 @@ public class IpcClient {
     static final boolean IS_WINDOWS =
             System.getProperty("os.name").toLowerCase(Locale.ENGLISH).contains("win");
 
-    volatile boolean initialized;
-    Path lockPath;
-    Path logPath;
-    Path syncPath;
-    SocketChannel socket;
-    DataOutputStream output;
-    DataInputStream input;
-    Thread receiver;
-    AtomicInteger requestId = new AtomicInteger();
-    Map<Integer, CompletableFuture<List<String>>> responses = new ConcurrentHashMap<>();
+    protected volatile boolean initialized;
+    protected final Path lockPath;
+    protected final Path logPath;
+    protected final Path syncPath;
+    protected final boolean noFork;
+
+    protected SocketChannel socket;
+    protected DataOutputStream output;
+    protected DataInputStream input;
+    protected Thread receiver;
+
+    protected final AtomicInteger requestId = new AtomicInteger();
+    protected final Map<Integer, CompletableFuture<List<String>>> responses = new ConcurrentHashMap<>();
 
     IpcClient(Path lockPath, Path logPath, Path syncPath) {
         this.lockPath = lockPath;
         this.logPath = logPath;
         this.syncPath = syncPath;
+        this.noFork = Boolean.parseBoolean(
+                System.getProperty(IpcServer.SYSTEM_PROP_NO_FORK, Boolean.toString(IpcServer.DEFAULT_NO_FORK)));
     }
 
     void ensureInitialized() throws IOException {
         if (!initialized) {
+            // caller must block on this method
             synchronized (this) {
                 if (!initialized) {
                     socket = createClient();
@@ -152,8 +158,6 @@ SocketChannel createClient() throws IOException {
                 Path logFile = logPath.resolve("resolver-ipcsync-" + rand + ".log");
                 List<String> args = new ArrayList<>();
                 if (noNative) {
-                    boolean noFork = Boolean.parseBoolean(System.getProperty(
-                            IpcServer.SYSTEM_PROP_NO_FORK, Boolean.toString(IpcServer.DEFAULT_NO_FORK)));
                     if (noFork) {
                         IpcServer server = IpcServer.runServer(family, tmpaddr, rand);
                         close = server::close;
@@ -326,6 +330,9 @@ List<String> send(List<String> request, long time, TimeUnit unit) throws Timeout
     }
 
     void close() {
+        if (noFork) {
+            stopServer();
+        }
         close(new IOException("Closing"));
     }
 

maven-resolver-named-locks-ipc/src/main/java/org/eclipse/aether/named/ipc/IpcServer.java

@@ -64,7 +64,7 @@ public class IpcServer {
      */
     public static final String SYSTEM_PROP_IDLE_TIMEOUT = "aether.named.ipc.idleTimeout";
 
-    public static final int DEFAULT_IDLE_TIMEOUT = 60;
+    public static final int DEFAULT_IDLE_TIMEOUT = 300;
 
     /**
      * IPC socket family to use.
@@ -359,7 +359,7 @@ private void client(SocketChannel socket) {
                 c = clients.size();
             }
             if (!closing) {
-                info("%d clients left", c);
+                info("%d clients remained", c);
             }
         }
     }
@@ -372,7 +372,7 @@ private void expirationCheck() {
         while (true) {
             long current = System.nanoTime();
             long left = (lastUsed + idleTimeout) - current;
-            if (left < 0) {
+            if (clients.isEmpty() && left < 0) {
                 info("IpcServer expired, closing");
                 close();
                 break;

maven-resolver-named-locks-ipc/src/test/java/org/eclipse/aether/named/ipc/IpcAdapterNoForkIT.java

@@ -0,0 +1,39 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+package org.eclipse.aether.named.ipc;
+
+import org.junit.jupiter.api.AfterAll;
+import org.junit.jupiter.api.BeforeAll;
+
+public class IpcAdapterNoForkIT extends NamedLockFactoryAdapterTestSupport {
+    @BeforeAll
+    static void createNamedLockFactory() {
+        // the goal if this IT to prove it works when noFork=true and IpcClient will clean up server
+        // needed in cases like in Maven, when there is no direct access to IpcNamedLockFactory
+        // to override doShutdown method like in IpcAdapterIT
+        System.setProperty(IpcServer.SYSTEM_PROP_NO_FORK, Boolean.TRUE.toString());
+        System.setProperty(IpcServer.SYSTEM_PROP_DEBUG, Boolean.TRUE.toString());
+        setNamedLockFactory(new IpcNamedLockFactory());
+    }
+
+    @AfterAll
+    static void cleanup() {
+        System.clearProperty(IpcServer.SYSTEM_PROP_NO_FORK);
+    }
+}