From a7658591315a9adcb3c959dfdf5e35de526d99e6 Mon Sep 17 00:00:00 2001
From: huzheng <openinx@gmail.com>
Date: Tue, 13 Nov 2018 11:33:22 +0800
Subject: [PATCH] HBASE-21473 RowIndexSeekerV1 may return cell with extra two
 \x00\x00 bytes which has no tags

---
 .../hbase/io/encoding/RowIndexSeekerV1.java   |  2 +-
 .../io/encoding/TestDataBlockEncoders.java    | 25 +++++++++++++++++++
 2 files changed, 26 insertions(+), 1 deletion(-)

diff --git a/hbase-common/src/main/java/org/apache/hadoop/hbase/io/encoding/RowIndexSeekerV1.java b/hbase-common/src/main/java/org/apache/hadoop/hbase/io/encoding/RowIndexSeekerV1.java
index e1f00e27911..e4c48fa299f 100644
--- a/hbase-common/src/main/java/org/apache/hadoop/hbase/io/encoding/RowIndexSeekerV1.java
+++ b/hbase-common/src/main/java/org/apache/hadoop/hbase/io/encoding/RowIndexSeekerV1.java
@@ -356,7 +356,7 @@ public class RowIndexSeekerV1 extends AbstractEncodedSeeker {
 
     protected int getCellBufSize() {
       int kvBufSize = KEY_VALUE_LEN_SIZE + keyLength + valueLength;
-      if (includesTags()) {
+      if (includesTags() && tagsLength > 0) {
         kvBufSize += Bytes.SIZEOF_SHORT + tagsLength;
       }
       return kvBufSize;
diff --git a/hbase-server/src/test/java/org/apache/hadoop/hbase/io/encoding/TestDataBlockEncoders.java b/hbase-server/src/test/java/org/apache/hadoop/hbase/io/encoding/TestDataBlockEncoders.java
index 5eb350f09da..5766517062b 100644
--- a/hbase-server/src/test/java/org/apache/hadoop/hbase/io/encoding/TestDataBlockEncoders.java
+++ b/hbase-server/src/test/java/org/apache/hadoop/hbase/io/encoding/TestDataBlockEncoders.java
@@ -43,6 +43,7 @@ import org.apache.hadoop.hbase.PrivateCellUtil;
 import org.apache.hadoop.hbase.Tag;
 import org.apache.hadoop.hbase.io.ByteArrayOutputStream;
 import org.apache.hadoop.hbase.io.compress.Compression;
+import org.apache.hadoop.hbase.io.compress.Compression.Algorithm;
 import org.apache.hadoop.hbase.io.hfile.HFileContext;
 import org.apache.hadoop.hbase.io.hfile.HFileContextBuilder;
 import org.apache.hadoop.hbase.nio.SingleByteBuff;
@@ -50,6 +51,7 @@ import org.apache.hadoop.hbase.testclassification.IOTests;
 import org.apache.hadoop.hbase.testclassification.LargeTests;
 import org.apache.hadoop.hbase.util.Bytes;
 import org.apache.hadoop.hbase.util.RedundantKVGenerator;
+import org.junit.Assert;
 import org.junit.ClassRule;
 import org.junit.Test;
 import org.junit.experimental.categories.Category;
@@ -323,6 +325,29 @@ public class TestDataBlockEncoders {
     }
   }
 
+  @Test
+  public void testRowIndexWithTagsButNoTagsInCell() throws IOException {
+    List<KeyValue> kvList = new ArrayList<>();
+    byte[] row = new byte[0];
+    byte[] family = new byte[0];
+    byte[] qualifier = new byte[0];
+    byte[] value = new byte[0];
+    KeyValue expectedKV = new KeyValue(row, family, qualifier, -1L, Type.Put, value);
+    kvList.add(expectedKV);
+    DataBlockEncoding encoding = DataBlockEncoding.ROW_INDEX_V1;
+    DataBlockEncoder encoder = encoding.getEncoder();
+    ByteBuffer encodedBuffer =
+        encodeKeyValues(encoding, kvList, getEncodingContext(Algorithm.NONE, encoding), false);
+    HFileContext meta =
+        new HFileContextBuilder().withHBaseCheckSum(false).withIncludesMvcc(includesMemstoreTS)
+            .withIncludesTags(includesTags).withCompression(Compression.Algorithm.NONE).build();
+    DataBlockEncoder.EncodedSeeker seeker = encoder.createSeeker(CellComparatorImpl.COMPARATOR,
+      encoder.newDataBlockDecodingContext(meta));
+    seeker.setCurrentBuffer(new SingleByteBuff(encodedBuffer));
+    Cell cell = seeker.getCell();
+    Assert.assertEquals(expectedKV.getLength(), ((KeyValue) cell).getLength());
+  }
+
   private void checkSeekingConsistency(List<DataBlockEncoder.EncodedSeeker> encodedSeekers,
       boolean seekBefore, Cell keyValue) {
     Cell expectedKeyValue = null;