1 files changed, 45 insertions, 34 deletions

diff --git a/src/main/java/com/it_jaros/jscanner/Scanner.java b/src/main/java/com/it_jaros/jscanner/Scanner.java
index f656854..e22f18c 100644
--- a/src/main/java/com/it_jaros/jscanner/Scanner.java
+++ b/src/main/java/com/it_jaros/jscanner/Scanner.java
@@ -69,11 +69,13 @@ public class Scanner implements AutoCloseable {
                 maxHostsLimit,
                 host -> () -> {
                     try {
+                        scan.getThreadCounter().inc();
                         scan.getHostCounter().inc();
                         scan.getHostTotalCounter().inc();
                         if (cancelled) return null;
                         return scanHostPorts(host, scan);
                     } finally {
+                        scan.getThreadCounter().dec();
                         scan.getHostCounter().dec();
                     }
                 },
@@ -94,21 +96,23 @@ public class Scanner implements AutoCloseable {
                     continue;
                 }
 
-                // No matter what happens we have to free the resources after getting ScanResult
+                ScanResult result = null;
                 try {
-                    ScanResult result = finishedHost.get();
-                    if (result != null) {
-                        consumer.accept(result);
-                    }
+                    result = finishedHost.get();
+                } catch (ExecutionException e) {
+                    System.err.printf("%s -> %s%n", e.getClass().getSimpleName(), e.getMessage());
                 } finally {
+                    // No matter what happens we have to free the resources after getting ScanResult
                     state.activeWorkers().release();
                     state.inPipeline().decrementAndGet();
-                    scan.getThreadCounter().dec();
+                }
+
+                // release workers first before consuming
+                if (result != null) {
+                    consumer.accept(result);
                 }
             } catch (InterruptedException e) {
                 Thread.currentThread().interrupt();
-            } catch (ExecutionException e) {
-                System.err.printf("%s -> %s%n", e.getClass().getSimpleName(), e.getMessage());
             }
         }
 
@@ -140,9 +144,14 @@ public class Scanner implements AutoCloseable {
                 portRange,
                 maxWorkersPerHost,
                 port -> () -> {
-                    waitForSlot(portSlotFactory);
-                    if (cancelled) return null;
-                    return checkPort(host, port, scan);
+                    try {
+                        scan.getThreadCounter().inc();
+                        waitForSlot(portSlotFactory);
+                        if (cancelled) return null;
+                        return checkPort(host, port, scan);
+                    } finally {
+                        scan.getThreadCounter().dec();
+                    }
                 },
                 scan.getThreadCounter()
         );
@@ -157,35 +166,39 @@ public class Scanner implements AutoCloseable {
                     continue;
                 }
 
+                PortResult portResult = null;
                 try {
-                    PortResult portResult = portResultFuture.get();
-                    if (portResult == null) continue;
-                    switch (portResult.getState()) {
-                        case OPEN -> {
-                            // bitset is not thread-safe, so it is set
-                            // outside the other virtual threads that update progress
-                            openPorts.set(portResult.getPort());
-                            serviceTypes.put(portResult.getPort(), ServiceDetector.detect(portResult.getBanner()));
-                        }
-                        case FILTERED -> {
-                            filteredPorts.set(portResult.getPort());
-                        }
-                        default -> {
-                            // sonarcube glücklich machen
-                        }
-                    }
-                    Exception e = portResult.getException();
-                    if (e != null) {
-                        scanFailures.add(new ScanFailure(portResult.getPort(), ExceptionInfo.from(e)));
-                    }
+                    portResult = portResultFuture.get();
                 } catch (ExecutionException e) {
                     // something more serious did not work
                     System.err.printf("%s -> %s%n", e.getClass().getSimpleName(), e.getMessage());
                 } finally {
-                    scan.getThreadCounter().dec();
                     state.activeWorkers().release();
                     state.inPipeline().decrementAndGet();
                 }
+
+                if (portResult == null) {
+                    continue;
+                }
+
+                switch (portResult.getState()) {
+                    case OPEN -> {
+                        // bitset is not thread-safe, so it is set
+                        // outside the other virtual threads that update progress
+                        openPorts.set(portResult.getPort());
+                        serviceTypes.put(portResult.getPort(), ServiceDetector.detect(portResult.getBanner()));
+                    }
+                    case FILTERED -> {
+                        filteredPorts.set(portResult.getPort());
+                    }
+                    default -> {
+                        // sonarcube glücklich machen
+                    }
+                }
+                Exception e = portResult.getException();
+                if (e != null) {
+                    scanFailures.add(new ScanFailure(portResult.getPort(), ExceptionInfo.from(e)));
+                }
             } catch (InterruptedException ignored) {
                 Thread.currentThread().interrupt();
             }
@@ -232,7 +245,6 @@ public class Scanner implements AutoCloseable {
                         final INPUT item = queue.next();
                         Callable<OUTPUT> task = taskFactory.apply(item);
                         inPipeline.incrementAndGet();
-                        threadCounter.inc();
                         try {
                             // here we are filling the completion service
                             // host <-> virtual thread
@@ -240,7 +252,6 @@ public class Scanner implements AutoCloseable {
                             submitted = true;
                         } catch (Throwable e) {
                             inPipeline.decrementAndGet();
-                            threadCounter.dec();
                             throw e;
                         }
                     } finally {