From 38c4680aae03be539c7adc64697c5c65a54d6d48 Mon Sep 17 00:00:00 2001
From: Alison Cichowlas <asc@google.com>
Date: Thu, 19 Jan 2017 09:47:17 -0500
Subject: [PATCH] Tron - Omit overlong lines and warn when doing so.

Test: updated LogBuilderTest

Change-Id: I0218acfacca53598a546cea5b3adeecd0d639031
---
 .../android/internal/logging/LogBuilder.java  | 23 ++++++++++++++++---
 .../internal/logging/MetricsLogger.java       |  3 ---
 .../internal/logging/LogBuilderTest.java      | 12 +++++++++-
 3 files changed, 31 insertions(+), 7 deletions(-)

diff --git a/core/java/com/android/internal/logging/LogBuilder.java b/core/java/com/android/internal/logging/LogBuilder.java
index 7eda3da70bbae..2d78979b4c03b 100644
--- a/core/java/com/android/internal/logging/LogBuilder.java
+++ b/core/java/com/android/internal/logging/LogBuilder.java
@@ -23,6 +23,7 @@ import android.view.View;
 import com.android.internal.logging.nano.MetricsProto.MetricsEvent;
 
 
+
 /**
  * Helper class to assemble more complex logs.
  *
@@ -31,6 +32,13 @@ import com.android.internal.logging.nano.MetricsProto.MetricsEvent;
 
 public class LogBuilder {
     private static final String TAG = "LogBuilder";
+
+    // Min required eventlog line length.
+    // See: android/util/cts/EventLogTest.java
+    // Size checks enforced here are intended only as sanity checks;
+    // your logs may be truncated earlier. Please log responsibly.
+    public static final int MAX_SERIALIZED_SIZE = 4000;
+
     private SparseArray<Object> entries = new SparseArray();
 
     public LogBuilder(int mainCategory) {
@@ -97,7 +105,11 @@ public class LogBuilder {
             throw new IllegalArgumentException(
                     "Value must be loggable type - int, long, float, String");
         }
-        entries.put(tag, value);
+        if (value.toString().getBytes().length > MAX_SERIALIZED_SIZE) {
+            Log.i(TAG, "Log value too long, omitted: " + value.toString());
+        } else {
+            entries.put(tag, value);
+        }
         return this;
     }
 
@@ -198,18 +210,23 @@ public class LogBuilder {
             out[i * 2] = entries.keyAt(i);
             out[i * 2 + 1] = entries.valueAt(i);
         }
+        int size = out.toString().getBytes().length;
+        if (size > MAX_SERIALIZED_SIZE) {
+            Log.i(TAG, "Log line too long, did not emit: " + size + " bytes.");
+            throw new RuntimeException();
+        }
         return out;
     }
 
     public void deserialize(Object[] items) {
         int i = 0;
-        while(i < items.length) {
+        while (i < items.length) {
             Object key = items[i++];
             Object value = i < items.length ? items[i++] : null;
             if (key instanceof Integer) {
                 entries.put((Integer) key, value);
             } else {
-              Log.i(TAG, "Invalid key " + key.toString());
+                Log.i(TAG, "Invalid key " + key.toString());
             }
         }
     }
diff --git a/core/java/com/android/internal/logging/MetricsLogger.java b/core/java/com/android/internal/logging/MetricsLogger.java
index 16c2719c0584e..b90336c442aa3 100644
--- a/core/java/com/android/internal/logging/MetricsLogger.java
+++ b/core/java/com/android/internal/logging/MetricsLogger.java
@@ -94,9 +94,6 @@ public class MetricsLogger {
     }
 
     public static void action(LogBuilder content) {
-        //EventLog.writeEvent(524292, content.serialize());
-        // Below would be the *right* way to do this, using the generated
-        // EventLogTags method, but that doesn't work.
         if (content.getType() == MetricsEvent.TYPE_UNKNOWN) {
             content.setType(MetricsEvent.TYPE_ACTION);
         }
diff --git a/core/tests/coretests/src/com/android/internal/logging/LogBuilderTest.java b/core/tests/coretests/src/com/android/internal/logging/LogBuilderTest.java
index a3405591182d3..1c19d88815cd6 100644
--- a/core/tests/coretests/src/com/android/internal/logging/LogBuilderTest.java
+++ b/core/tests/coretests/src/com/android/internal/logging/LogBuilderTest.java
@@ -107,11 +107,21 @@ public class LogBuilderTest extends TestCase {
         assertEquals(123.0F, out[7]);
     }
 
-  public void testCategoryDefault() {
+    public void testCategoryDefault() {
         LogBuilder builder = new LogBuilder(10);
         Object[] out = builder.serialize();
         assertEquals(MetricsEvent.RESERVED_FOR_LOGBUILDER_CATEGORY, out[0]);
         assertEquals(10, out[1]);
     }
 
+    public void testGiantLogOmitted() {
+        LogBuilder badBuilder = new LogBuilder(0);
+        StringBuilder b = new StringBuilder();
+        for (int i = 0; i < 4000; i++) {
+            b.append("test, " + i);
+        }
+        badBuilder.addTaggedData(100, b.toString());
+        assertTrue(badBuilder.serialize().length < LogBuilder.MAX_SERIALIZED_SIZE);
+    }
+
 }