From 365d6b916ef189fc3a8d08113050e6ecbdb77603 Mon Sep 17 00:00:00 2001
From: Nikita Koksharov <nkoksharov@redisson.pro>
Date: Sat, 7 Oct 2023 13:27:26 +0300
Subject: [PATCH] Fixed - RReadWriteLock.readLock().isLocked() method returns
 incorrect result if acquired by writeLock owner thread. #4400

---
 .../java/org/redisson/RedissonReadLock.java   | 12 +++--
 .../redisson/RedissonReadWriteLockTest.java   | 45 ++++++++++---------
 2 files changed, 33 insertions(+), 24 deletions(-)

diff --git a/redisson/src/main/java/org/redisson/RedissonReadLock.java b/redisson/src/main/java/org/redisson/RedissonReadLock.java
index b0ee38171..7e5260e37 100644
--- a/redisson/src/main/java/org/redisson/RedissonReadLock.java
+++ b/redisson/src/main/java/org/redisson/RedissonReadLock.java
@@ -195,9 +195,15 @@ public class RedissonReadLock extends RedissonLock implements RLock {
 
     @Override
     public boolean isLocked() {
-        RFuture<String> future = commandExecutor.writeAsync(getRawName(), StringCodec.INSTANCE, RedisCommands.HGET, getRawName(), "mode");
-        String res = get(future);
-        return "read".equals(res);
+        RFuture<Boolean> future = commandExecutor.evalWriteAsync(getRawName(), LongCodec.INSTANCE, RedisCommands.EVAL_BOOLEAN,
+          "local mode = redis.call('hget', KEYS[1], 'mode'); " +
+                "if (mode == 'read') or (mode == 'write' and redis.call('hlen', KEYS[1]) > 2) then " +
+                    "return 1; " +
+                "end; " +
+                "return 0; ",
+                Arrays.asList(getRawName()));
+
+        return get(future);
     }
 
 }
diff --git a/redisson/src/test/java/org/redisson/RedissonReadWriteLockTest.java b/redisson/src/test/java/org/redisson/RedissonReadWriteLockTest.java
index cf4d73e96..5ff6e46aa 100644
--- a/redisson/src/test/java/org/redisson/RedissonReadWriteLockTest.java
+++ b/redisson/src/test/java/org/redisson/RedissonReadWriteLockTest.java
@@ -1,36 +1,27 @@
 package org.redisson;
 
-import static org.assertj.core.api.Assertions.assertThat;
-import static org.assertj.core.api.Assertions.assertThatCode;
-import static org.awaitility.Awaitility.await;
+import org.awaitility.Awaitility;
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Test;
+import org.redisson.ClusterRunner.ClusterProcesses;
+import org.redisson.api.RLock;
+import org.redisson.api.RReadWriteLock;
+import org.redisson.api.RedissonClient;
+import org.redisson.config.Config;
 
 import java.security.SecureRandom;
 import java.time.Duration;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Random;
-import java.util.concurrent.Callable;
-import java.util.concurrent.CountDownLatch;
-import java.util.concurrent.ExecutionException;
-import java.util.concurrent.ExecutorService;
-import java.util.concurrent.Executors;
-import java.util.concurrent.Future;
-import java.util.concurrent.TimeUnit;
-import java.util.concurrent.TimeoutException;
+import java.util.concurrent.*;
 import java.util.concurrent.atomic.AtomicBoolean;
 import java.util.concurrent.atomic.AtomicInteger;
 import java.util.concurrent.atomic.AtomicReference;
-import java.util.concurrent.locks.ReadWriteLock;
-import java.util.concurrent.locks.ReentrantReadWriteLock;
 
-import org.awaitility.Awaitility;
-import org.junit.jupiter.api.Assertions;
-import org.junit.jupiter.api.Test;
-import org.redisson.ClusterRunner.ClusterProcesses;
-import org.redisson.api.RLock;
-import org.redisson.api.RReadWriteLock;
-import org.redisson.api.RedissonClient;
-import org.redisson.config.Config;
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatCode;
+import static org.awaitility.Awaitility.await;
 
 public class RedissonReadWriteLockTest extends BaseConcurrentTest {
 
@@ -76,6 +67,18 @@ public class RedissonReadWriteLockTest extends BaseConcurrentTest {
         Awaitility.await().between(8, TimeUnit.SECONDS, 10, TimeUnit.SECONDS).untilTrue(flag);
     }
 
+    @Test
+    public void testReadLockIsLocked() throws InterruptedException {
+        RReadWriteLock readWriteLock = redisson.getReadWriteLock("TEST");
+        RLock writeLock = readWriteLock.writeLock();
+        RLock readLock = readWriteLock.readLock();
+
+        writeLock.lock();
+        assertThat(readLock.isLocked()).isFalse();
+        assertThat(readLock.tryLock(10, TimeUnit.SECONDS)).isTrue();
+        assertThat(readLock.isLocked()).isTrue();
+    }
+
     @Test
     public void testReadLockExpirationRenewal() throws InterruptedException {
         int threadCount = 50;