EventLog: event log translation errors

- Deal with L using v3 event log format, or K using v1 or v2 event log format

Change-Id: Id4fb205f51b7e506135888d565acf1604497b91f

1 files changed, 17 insertions, 7 deletions

diff --git a/core/java/android/util/EventLog.java b/core/java/android/util/EventLog.java
index 29c0ba2f3008..aefced8a6260 100644
--- a/core/java/android/util/EventLog.java
+++ b/core/java/android/util/EventLog.java
@@ -56,16 +56,18 @@ public class EventLog {
     public static final class Event {
         private final ByteBuffer mBuffer;
 
-        // Layout of event log entry received from kernel.
+        // Layout of event log entry received from Android logger.
+        //  see system/core/include/log/logger.h
         private static final int LENGTH_OFFSET = 0;
+        private static final int HEADER_SIZE_OFFSET = 2;
         private static final int PROCESS_OFFSET = 4;
         private static final int THREAD_OFFSET = 8;
         private static final int SECONDS_OFFSET = 12;
         private static final int NANOSECONDS_OFFSET = 16;
 
-        private static final int PAYLOAD_START = 20;
-        private static final int TAG_OFFSET = 20;
-        private static final int DATA_START = 24;
+        // Layout for event log v1 format, v2 and v3 use HEADER_SIZE_OFFSET
+        private static final int V1_PAYLOAD_START = 20;
+        private static final int DATA_OFFSET = 4;
 
         // Value types
         private static final byte INT_TYPE    = 0;
@@ -97,14 +99,22 @@ public class EventLog {
 
         /** @return the type tag code of the entry */
         public int getTag() {
-            return mBuffer.getInt(TAG_OFFSET);
+            int offset = mBuffer.getShort(HEADER_SIZE_OFFSET);
+            if (offset == 0) {
+                offset = V1_PAYLOAD_START;
+            }
+            return mBuffer.getInt(offset);
         }
 
         /** @return one of Integer, Long, String, null, or Object[] of same. */
         public synchronized Object getData() {
             try {
-                mBuffer.limit(PAYLOAD_START + mBuffer.getShort(LENGTH_OFFSET));
-                mBuffer.position(DATA_START);  // Just after the tag.
+                int offset = mBuffer.getShort(HEADER_SIZE_OFFSET);
+                if (offset == 0) {
+                    offset = V1_PAYLOAD_START;
+                }
+                mBuffer.limit(offset + mBuffer.getShort(LENGTH_OFFSET));
+                mBuffer.position(offset + DATA_OFFSET); // Just after the tag.
                 return decodeObject();
             } catch (IllegalArgumentException e) {
                 Log.wtf(TAG, "Illegal entry payload: tag=" + getTag(), e);