fixed issue #2099 , support user/passwd acl and canal admin operator

common/src/main/java/com/alibaba/otter/canal/common/utils/FileUtils.java

@@ -12,20 +12,24 @@ public class FileUtils {
     private static final Logger logger = LoggerFactory.getLogger(FileUtils.class);
 
     public static String readFileFromOffset(String filename, int l, String charset) {
+        return readFileFromOffset(filename, l, charset, 4 * 1024 * 1024);
+    }
+
+    public static String readFileFromOffset(String filename, int l, String charset, int maxSize) {
         RandomAccessFile rf = null;
         StringBuilder res = new StringBuilder();
         try {
             rf = new RandomAccessFile(filename, "r");
-
             long fileLength = rf.length();
-
             long start = rf.getFilePointer();
-
             long readIndex = start + fileLength - 1;
+            long minIndex = readIndex - maxSize;
+            if (minIndex < 0) {
+                minIndex = 0;
+            }
 
             String line;
             rf.seek(readIndex);
-
             int k = 0;
             int c = -1;
             while (readIndex > start) {
@@ -48,7 +52,12 @@ public class FileUtils {
                     readIndex--;
                 }
                 readIndex--;
-                rf.seek(readIndex);
+                if (readIndex < minIndex) {
+                    break;
+                } else {
+                    rf.seek(readIndex);
+                }
+
                 if (readIndex == 0) {
                     readText = rf.readLine();
                 }

common/src/main/java/com/alibaba/otter/canal/common/zookeeper/running/ServerRunningMonitor.java

@@ -148,6 +148,7 @@ public class ServerRunningMonitor extends AbstractCanalLifeCycle {
             activeData = serverData;
             processActiveEnter();// 触发一下事件
             mutex.set(true);
+            release = false;
         } catch (ZkNodeExistsException e) {
             bytes = zkClient.readData(path, true);
             if (bytes == null) {// 如果不存在节点，立即尝试一次