Temp Workaround to recovery from bad string size, apache#432

Since the registry data is invalid, i simply empty the content to guarantee the next registry will work correct.

common/src/main/java/org/mvndaemon/mvnd/common/DaemonRegistry.java

@@ -16,7 +16,9 @@
 
 package org.mvndaemon.mvnd.common;
 
-import java.io.File;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
 import java.io.IOException;
 import java.lang.management.ManagementFactory;
 import java.nio.MappedByteBuffer;
@@ -35,8 +37,6 @@
 import java.util.Random;
 import java.util.concurrent.ConcurrentHashMap;
 import java.util.stream.Collectors;
-import org.slf4j.Logger;
-import org.slf4j.LoggerFactory;
 
 import static org.mvndaemon.mvnd.common.DaemonState.Canceled;
 import static org.mvndaemon.mvnd.common.DaemonState.Idle;
@@ -242,12 +242,28 @@ private void doUpdate(Runnable updater) {
                     return;
                 } catch (IOException e) {
                     throw new RuntimeException("Could not lock offset 0 of " + registryFile);
+                } catch (IllegalStateException e) {
+                    String absPath = registryFile.toAbsolutePath().normalize().toString();
+                    LOGGER.warn("Invalid daemon registry info, " +
+                            "try to recovery this issue by reset registry buffer. " +
+                            "If you keep getting this warning, " +
+                            "try to delete `registry.bin` file at [" + absPath + "]", e);
+                    this.reset();
+                    return;
                 }
             }
             throw new RuntimeException("Could not lock " + registryFile + " within " + LOCK_TIMEOUT_MS + " ms");
         }
     }
 
+    private void reset() {
+        infosMap.clear();
+        stopEvents.clear();
+        BufferCaster.cast(buffer).clear();
+        buffer.putInt(0); // reset daemon count
+        buffer.putInt(0); // reset stop event count
+    }
+
     private static final int PROCESS_ID = getProcessId0();
 
     private static int getProcessId0() {

common/src/test/java/org/mvndaemon/mvnd/common/DaemonRegistryTest.java

@@ -15,13 +15,14 @@
  */
 package org.mvndaemon.mvnd.common;
 
+import org.junit.jupiter.api.Test;
+
 import java.io.File;
 import java.io.IOException;
 import java.nio.file.Path;
 import java.util.Arrays;
 import java.util.Locale;
 import java.util.Random;
-import org.junit.jupiter.api.Test;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import static org.junit.jupiter.api.Assertions.assertNotNull;
@@ -50,7 +51,32 @@ public void testReadWrite() throws IOException {
             assertNotNull(reg2.getAll());
             assertEquals(1, reg2.getAll().size());
         }
+    }
 
+    @Test
+    public void testRecovery() throws IOException {
+        Path temp = File.createTempFile("reg", ".data").toPath();
+        temp.toFile().deleteOnExit();
+        try (DaemonRegistry reg1 = new DaemonRegistry(temp)) {
+            // first store daemon
+            byte[] token = new byte[16];
+            new Random().nextBytes(token);
+            reg1.store(new DaemonInfo("12345678", "/java/home/",
+                    "/data/reg/", 0x12345678, 7502, token,
+                    Locale.getDefault().toLanguageTag(), Arrays.asList("-Xmx"),
+                    DaemonState.Idle, System.currentTimeMillis(), System.currentTimeMillis()));
+            assertEquals(1, reg1.getAll().size());
+            // store an invalid event to trigger recovery
+            reg1.storeStopEvent(new DaemonStopEvent("11111",
+                    System.currentTimeMillis(),
+                    DaemonExpirationStatus.QUIET_EXPIRE,
+                    "reason txt longer than 1024, reason txt longer than 1024, reason txt longer than 1024, reason txt longer than 1024, reason txt longer than 1024, reason txt longer than 1024, reason txt longer than 1024, reason txt longer than 1024, reason txt longer than 1024, reason txt longer than 1024, reason txt longer than 1024, reason txt longer than 1024, reason txt longer than 1024, reason txt longer than 1024, reason txt longer than 1024, reason txt longer than 1024, reason txt longer than 1024, reason txt longer than 1024, reason txt longer than 1024, reason txt longer than 1024, reason txt longer than 1024, reason txt longer than 1024, reason txt longer than 1024, reason txt longer than 1024, reason txt longer than 1024, reason txt longer than 1024, reason txt longer than 1024, reason txt longer than 1024, reason txt longer than 1024, reason txt longer than 1024, reason txt longer than 1024, reason txt longer than 1024, reason txt longer than 1024, reason txt longer than 1024, reason txt longer than 1024, reason txt longer than 1024, reason txt longer than 1024"
+            ));
+            // check if registry is reset
+            assertEquals(0, reg1.getAll().size());
+        }
     }
 
+
+
 }