merge: #8294

8294: [Backport stable/1.2] fix(journal): prevent concurrent delete and reader creation r=deepthidevaki a=github-actions[bot]

# Description
Backport of #8293 to `stable/1.2`.

relates to #7962

Co-authored-by: Deepthi Devaki Akkoorath <deepthidevaki@gmail.com>

Author: zeebe-bors-cloud[bot]

journal/src/main/java/io/camunda/zeebe/journal/file/SegmentedJournal.java

@@ -149,22 +149,27 @@ public void deleteUntil(final long index) {
         return;
       }
 
-      log.debug(
-          "{} - Deleting log up from {} up to {} (removing {} segments)",
-          name,
-          getFirstIndex(),
-          compactSegments.get(compactSegments.lastKey()).index(),
-          compactSegments.size());
-      for (final JournalSegment segment : compactSegments.values()) {
-        log.trace("{} - Deleting segment: {}", name, segment);
-        segment.delete();
-        journalMetrics.decSegmentCount();
-      }
+      final var stamp = rwlock.writeLock();
+      try {
+        log.debug(
+            "{} - Deleting log up from {} up to {} (removing {} segments)",
+            name,
+            getFirstIndex(),
+            compactSegments.get(compactSegments.lastKey()).index(),
+            compactSegments.size());
+        for (final JournalSegment segment : compactSegments.values()) {
+          log.trace("{} - Deleting segment: {}", name, segment);
+          segment.delete();
+          journalMetrics.decSegmentCount();
+        }
 
-      // removes them from the segment map
-      compactSegments.clear();
+        // removes them from the segment map
+        compactSegments.clear();
 
-      journalIndex.deleteUntil(index);
+        journalIndex.deleteUntil(index);
+      } finally {
+        rwlock.unlockWrite(stamp);
+      }
     }
   }
 

journal/src/test/java/io/camunda/zeebe/journal/file/SegmentedJournalTest.java

@@ -509,6 +509,35 @@ void shouldNotFailOnResetAndOpeningReaderConcurrently() throws InterruptedExcept
     assertThat(latch.await(1, TimeUnit.SECONDS)).isTrue();
   }
 
+  // Regression test for https://github.com/camunda-cloud/zeebe/issues/7962
+  @Test
+  void shouldNotFailOnDeleteAndOpeningReaderConcurrently() throws InterruptedException {
+    // given
+    final var latch = new CountDownLatch(2);
+    final var journal = openJournal(2);
+    for (int i = 0; i < 10; i++) {
+      journal.append(data);
+    }
+    final long indexToCompact = journal.append(data).index();
+
+    // when
+    new Thread(
+            () -> {
+              journal.deleteUntil(indexToCompact);
+              latch.countDown();
+            })
+        .start();
+    new Thread(
+            () -> {
+              journal.openReader();
+              latch.countDown();
+            })
+        .start();
+
+    // then
+    assertThat(latch.await(1, TimeUnit.SECONDS)).isTrue();
+  }
+
   @Test
   void shouldDeleteSegmentFileWhenReaderIsClosed() {
     // given