From f4606dd63d611701012c80ba289b4f273ae08ce2 Mon Sep 17 00:00:00 2001
From: Claude <noreply@anthropic.com>
Date: Mon, 23 Mar 2026 11:53:34 +0000
Subject: [PATCH] Fix race condition in AbstractProducer.run() allowing
 uninitialized execution

Add two guards at the start of run(): (1) check shouldRun to handle the
case where interrupt() is called before the executor thread starts, and
(2) verify state is INITIALIZED to prevent producing keys without proper
initialization. This fixes a sporadic IllegalStateException in
ProducerOpenCL where the OpenCL context could be null if releaseProducer()
ran before the executor thread started.

https://claude.ai/code/session_017zaPZjBcrkXejsmU8h5F9r
---
 .../AbstractProducer.java                     |  8 ++++
 .../AbstractProducerTest.java                 | 39 +++++++++++++++++++
 2 files changed, 47 insertions(+)

diff --git a/src/main/java/net/ladenthin/bitcoinaddressfinder/AbstractProducer.java b/src/main/java/net/ladenthin/bitcoinaddressfinder/AbstractProducer.java
index f68616d..58e6ea5 100644
--- a/src/main/java/net/ladenthin/bitcoinaddressfinder/AbstractProducer.java
+++ b/src/main/java/net/ladenthin/bitcoinaddressfinder/AbstractProducer.java
@@ -69,6 +69,14 @@ public void releaseProducer() {
 
     @Override
     public void run() {
+        if (!shouldRun.get()) {
+            logger.info("Producer was interrupted before it started running.");
+            state = ProducerState.NOT_RUNNING;
+            return;
+        }
+        if (state != ProducerState.INITIALIZED) {
+            throw new IllegalStateException("Producer not initialized. Current state: " + state);
+        }
         state = ProducerState.RUNNING;
         while (shouldRun.get()) {
             try {
diff --git a/src/test/java/net/ladenthin/bitcoinaddressfinder/AbstractProducerTest.java b/src/test/java/net/ladenthin/bitcoinaddressfinder/AbstractProducerTest.java
index d5c2b21..49e7060 100644
--- a/src/test/java/net/ladenthin/bitcoinaddressfinder/AbstractProducerTest.java
+++ b/src/test/java/net/ladenthin/bitcoinaddressfinder/AbstractProducerTest.java
@@ -236,6 +236,45 @@ static void verifyInitProducer(AbstractProducer abstractProducer) {
     }
 
     // <editor-fold defaultstate="collapsed" desc="run">
+    @Test(expected = IllegalStateException.class)
+    public void run_notInitialized_illegalStateExceptionThrown() throws IOException, InterruptedException {
+        // arrange
+        CProducer cProducer = new CProducer();
+        MockConsumer mockConsumer = new MockConsumer();
+        Random random = new Random(1);
+        MockKeyProducer mockKeyProducer = new MockKeyProducer(keyUtility, random);
+        AbstractProducerTestImpl abstractProducerTestImpl = new AbstractProducerTestImpl(cProducer, mockConsumer, keyUtility, mockKeyProducer, bitHelper);
+
+        // act
+        abstractProducerTestImpl.run();
+    }
+
+    @Test
+    public void run_interruptedBeforeStarted_stateSetToNotRunning() throws IOException, InterruptedException {
+        // arrange
+        CProducer cProducer = new CProducer();
+        MockConsumer mockConsumer = new MockConsumer();
+        Random random = new Random(1);
+        MockKeyProducer mockKeyProducer = new MockKeyProducer(keyUtility, random);
+        AbstractProducerTestImpl abstractProducerTestImpl = new AbstractProducerTestImpl(cProducer, mockConsumer, keyUtility, mockKeyProducer, bitHelper);
+
+        Logger logger = mock(Logger.class);
+        abstractProducerTestImpl.setLogger(logger);
+        abstractProducerTestImpl.initProducer();
+        abstractProducerTestImpl.interrupt();
+
+        // act
+        abstractProducerTestImpl.run();
+
+        // assert
+        assertThat(abstractProducerTestImpl.state, is(equalTo(ProducerState.NOT_RUNNING)));
+
+        ArgumentCaptor<String> logCaptor = ArgumentCaptor.forClass(String.class);
+        verify(logger, times(2)).info(logCaptor.capture());
+        List<String> arguments = logCaptor.getAllValues();
+        assertThat(arguments.get(1), is(equalTo("Producer was interrupted before it started running.")));
+    }
+
     @Test
     public void run_exceptionInProduceKeys_exceptionCaughtAndLoggedToError() throws IOException, InterruptedException {
         // arrange