From 0c433cd1eb27930868128e396ee2e75689565698 Mon Sep 17 00:00:00 2001
From: Islam AbdelRahman <tec@fb.com>
Date: Tue, 26 Jan 2016 14:47:42 -0800
Subject: [PATCH] Fix issue in Iterator::Seek when using Block based filter
 block with prefix_extractor

Summary: Similar to D53385 we need to check InDomain before checking the filter block.

Test Plan: unit tests

Reviewers: yhchiang, rven, sdong

Reviewed By: sdong

Subscribers: dhruba

Differential Revision: https://reviews.facebook.net/D53421
---
 db/db_test.cc                     | 34 +++++++++++++++++++++++++++++++
 table/block_based_table_reader.cc |  7 +++++--
 2 files changed, 39 insertions(+), 2 deletions(-)

diff --git a/db/db_test.cc b/db/db_test.cc
index 5111c05ce..1296bad06 100644
--- a/db/db_test.cc
+++ b/db/db_test.cc
@@ -10082,6 +10082,7 @@ class SliceTransformLimitedDomain : public SliceTransform {
 
 TEST_F(DBTest, PrefixExtractorFullFilter) {
   BlockBasedTableOptions bbto;
+  // Full Filter Block
   bbto.filter_policy.reset(rocksdb::NewBloomFilterPolicy(10, false));
   bbto.whole_key_filtering = false;
 
@@ -10108,6 +10109,39 @@ TEST_F(DBTest, PrefixExtractorFullFilter) {
   ASSERT_EQ(Get("zzzzz_AAAA"), "val5");
 }
 
+TEST_F(DBTest, PrefixExtractorBlockFilter) {
+  BlockBasedTableOptions bbto;
+  // Block Filter Block
+  bbto.filter_policy.reset(rocksdb::NewBloomFilterPolicy(10, true));
+
+  Options options = CurrentOptions();
+  options.prefix_extractor = std::make_shared<SliceTransformLimitedDomain>();
+  options.table_factory.reset(NewBlockBasedTableFactory(bbto));
+
+  DestroyAndReopen(options);
+
+  ASSERT_OK(Put("x1113_AAAA", "val3"));
+  ASSERT_OK(Put("x1114_AAAA", "val4"));
+  // Not in domain, wont be added to filter
+  ASSERT_OK(Put("zzzzz_AAAA", "val1"));
+  ASSERT_OK(Put("zzzzz_AAAB", "val2"));
+  ASSERT_OK(Put("zzzzz_AAAC", "val3"));
+  ASSERT_OK(Put("zzzzz_AAAD", "val4"));
+
+  ASSERT_OK(Flush());
+
+  std::vector<std::string> iter_res;
+  auto iter = db_->NewIterator(ReadOptions());
+  // Seek to a key that was not in Domain
+  for (iter->Seek("zzzzz_AAAA"); iter->Valid(); iter->Next()) {
+    iter_res.emplace_back(iter->value().ToString());
+  }
+
+  std::vector<std::string> expected_res = {"val1", "val2", "val3", "val4"};
+  ASSERT_EQ(iter_res, expected_res);
+  delete iter;
+}
+
 #ifndef ROCKSDB_LITE
 class BloomStatsTestWithParam
     : public DBTest,
diff --git a/table/block_based_table_reader.cc b/table/block_based_table_reader.cc
index 3114a6f15..00997f3ea 100644
--- a/table/block_based_table_reader.cc
+++ b/table/block_based_table_reader.cc
@@ -1120,8 +1120,11 @@ bool BlockBasedTable::PrefixMayMatch(const Slice& internal_key) {
   }
 
   assert(rep_->ioptions.prefix_extractor != nullptr);
-  auto prefix = rep_->ioptions.prefix_extractor->Transform(
-      ExtractUserKey(internal_key));
+  auto user_key = ExtractUserKey(internal_key);
+  if (!rep_->ioptions.prefix_extractor->InDomain(user_key)) {
+    return true;
+  }
+  auto prefix = rep_->ioptions.prefix_extractor->Transform(user_key);
   InternalKey internal_key_prefix(prefix, kMaxSequenceNumber, kTypeValue);
   auto internal_prefix = internal_key_prefix.Encode();