Subprocesses and Interruption

src/main/java/org/buildobjects/process/Proc.java

@@ -77,28 +77,35 @@ public Proc(String command,
             throw new StartupException("Could not startup process '" + toString() + "'.", e);
         }
 
-        try {
             startControlThread();
 
             do {
-                ExecutionEvent nextEvent = timeout == null ? eventQueue.poll(MAX_VALUE, HOURS) : eventQueue.poll(timeout, MILLISECONDS);
+                try {
+                    ExecutionEvent nextEvent = timeout == null ? eventQueue.poll(MAX_VALUE, HOURS) : eventQueue.poll(timeout, MILLISECONDS);
 
-                if (nextEvent == null) {
-                    killCleanUpAndThrowTimeoutException();
-                }
+                    if (nextEvent == null) {
+                        killCleanUpAndThrowTimeoutException();
+                    }
 
-                if (nextEvent == PROCESS_EXITED) {
-                    break;
-                }
+                    if (nextEvent == PROCESS_EXITED) {
+                        break;
+                    }
 
-                if (nextEvent == EXCEPTION_IN_STREAM_HANDLING) {
+                    if (nextEvent == EXCEPTION_IN_STREAM_HANDLING) {
+                        killProcessCleanup();
+                        break;
+                    }
+                } catch (InterruptedException e) {
+                    // if this thread is interrupted, the process is destroyed
+                    // the process gets an exit code, so the next event is PROCESS_EXITED
                     killProcessCleanup();
-                    break;
+                    continue;
                 }
 
                 throw new RuntimeException("Felix reckons we should never reach this point");
             } while (true);
 
+        try {
             List<Throwable> exceptions = ioHandler.joinConsumption();
             if (!exceptions.isEmpty()) {
                 throw new IllegalStateException("Exception in stream consumption", exceptions.get(0));
@@ -150,14 +157,31 @@ public void run() {
     }
 
     private void killCleanUpAndThrowTimeoutException() {
-        process.destroy();
-        ioHandler.cancelConsumption();
+        killProcessCleanup();
         throw new TimeoutException(toString(), timeout);
     }
 
     private void killProcessCleanup() {
-        process.destroy();
+        List<Throwable> throwables = new ArrayList<>();
+
+        // destroy this process and all sub processes
+        ProcessHandle.of(process.pid())
+            .ifPresentOrElse(rootHandle -> {
+                rootHandle.descendants()
+                    .forEach(subHandle -> {
+                        try {
+                            subHandle.destroy();
+                        }
+                        catch (Throwable t) {
+                            throwables.add(new IllegalStateException("Could not destroy process " + subHandle.pid(), t));
+                        }
+                    });
+                rootHandle.destroy();
+            }, process::destroy);
         ioHandler.cancelConsumption();
+
+        if(!throwables.isEmpty())
+            throw new RuntimeException(throwables.get(0));
     }
 
     public void dispatch(ExecutionEvent event) {

src/test/java/org/buildobjects/process/ProcBuilderTest.java

@@ -5,6 +5,9 @@
 import java.io.*;
 import java.util.HashMap;
 import java.util.Map;
+import java.util.concurrent.CompletableFuture;
+import java.util.concurrent.atomic.AtomicBoolean;
+import java.util.concurrent.atomic.AtomicReference;
 
 import static org.junit.Assert.*;
 
@@ -262,6 +265,41 @@ public void testDisablingTimeout() {
         assertEquals(result.getExecutionTime(), 7000, 500);
     }
 
+    /**
+     * Tests if the process stops the execution when the thread is interrupted
+     */
+    @Test
+    public void testInterruptingProcess() throws InterruptedException {
+        AtomicBoolean finished = new AtomicBoolean(false);
+        AtomicReference<ProcResult> resultRef = new AtomicReference<>(null);
+
+        Thread executorThread = new Thread(new Runnable() {
+            @Override
+            public void run() {
+                resultRef.set(new ProcBuilder("sleep")
+                        .withArg("10")
+                        .ignoreExitStatus()
+                        .withNoTimeout()
+                        .run());
+                finished.set(true);
+            }
+        });
+        executorThread.start();
+
+        // wait some time
+        Thread.sleep(2000);
+
+        // stop the thread
+        executorThread.interrupt();
+
+        // wait shortly
+        Thread.sleep(500);
+
+        assertTrue(finished.get());
+        assertNotNull(resultRef.get());
+        assertEquals(2000, resultRef.get().getExecutionTime(), 300);
+    }
+
     /**
      * Exit Status
      * -----------
@@ -384,6 +422,37 @@ public void testHonorsOnlyDefinedExitStatuses() {
         }
     }
 
+    /**
+     * If the process is interrupted, the exit code should be 1
+     */
+    @Test
+    public void testExitStatusWhenProcessIsInterrupted() throws InterruptedException {
+        AtomicReference<ProcResult> resultRef = new AtomicReference<>(null);
+        Thread executorThread = new Thread(new Runnable() {
+            @Override
+            public void run() {
+                resultRef.set(new ProcBuilder("sleep")
+                                .withArg("10")
+                                .withExpectedExitStatuses(1)
+                                .withNoTimeout()
+                                .run());
+            }
+        });
+        executorThread.start();
+
+        // wait some time
+        Thread.sleep(2000);
+
+        // stop the thread
+        executorThread.interrupt();
+
+        // wait shortly
+        Thread.sleep(500);
+
+        assertNotNull(resultRef.get());
+        assertEquals(1, resultRef.get().getExitValue());
+    }
+
     /**
      *
      * Good to Know