Log netd traffic nicely.

Create a LocalLog class for logging within a service for dumping in dumps.
Use it in the NativeDaemonConnector so we can get some insight into what
is happening in these lockups.

bug:5864209
Change-Id: I68ddc58847f3c8de613be9528570f8c3157d8274

1 files changed, 56 insertions, 0 deletions

diff --git a/core/java/android/util/LocalLog.java b/core/java/android/util/LocalLog.java
new file mode 100644
index 0000000..641d1b4
--- /dev/null
+++ b/core/java/android/util/LocalLog.java
@@ -0,0 +1,56 @@
+/*
+ * Copyright (C) 2006 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package android.util;
+
+import android.text.format.Time;
+
+import java.io.FileDescriptor;
+import java.io.PrintWriter;
+import java.io.StringWriter;
+import java.util.Iterator;
+import java.util.LinkedList;
+
+/**
+ * @hide
+ */
+public final class LocalLog {
+
+    private LinkedList<String> mLog;
+    private int mMaxLines;
+    private Time mNow;
+
+    public LocalLog(int maxLines) {
+        mLog = new LinkedList<String>();
+        mMaxLines = maxLines;
+        mNow = new Time();
+    }
+
+    public synchronized void log(String msg) {
+        if (mMaxLines > 0) {
+            mNow.setToNow();
+            mLog.add(mNow.format("%H:%M:%S") + " - " + msg);
+            while (mLog.size() > mMaxLines) mLog.remove();
+        }
+    }
+
+    public synchronized void dump(FileDescriptor fd, PrintWriter pw, String[] args) {
+        Iterator<String> itr = mLog.listIterator(0);
+        while (itr.hasNext()) {
+            pw.println(itr.next());
+        }
+    }
+}