From 3613d862ba0cae1ff31bd194e083f0e91bd7f7dc Mon Sep 17 00:00:00 2001
From: Yanqin Jin <yanqin@fb.com>
Date: Mon, 29 Aug 2022 14:13:06 -0700
Subject: [PATCH] print value when verification fails (#10587)

Summary:
When verification fails for db_stress, print more information about
value read from the db and expected state.

Pull Request resolved: https://github.com/facebook/rocksdb/pull/10587

Test Plan:
make check
./db_stress

Reviewed By: akankshamahajan15, hx235

Differential Revision: D39078511

Pulled By: riversand963

fbshipit-source-id: 77ac8ffae01fc3a9b58a02c2e7bbe141e1a18f0b
---
 db_stress_tool/db_stress_test_base.cc   | 13 +++++++++++++
 db_stress_tool/db_stress_test_base.h    |  4 ++++
 db_stress_tool/no_batched_ops_stress.cc | 15 ++++++++++-----
 3 files changed, 27 insertions(+), 5 deletions(-)

diff --git a/db_stress_tool/db_stress_test_base.cc b/db_stress_tool/db_stress_test_base.cc
index 05d688400..387595831 100644
--- a/db_stress_tool/db_stress_test_base.cc
+++ b/db_stress_tool/db_stress_test_base.cc
@@ -411,6 +411,19 @@ void StressTest::VerificationAbort(SharedState* shared, std::string msg, int cf,
   shared->SetVerificationFailure();
 }
 
+void StressTest::VerificationAbort(SharedState* shared, std::string msg, int cf,
+                                   int64_t key, Slice value_from_db,
+                                   Slice value_from_expected) const {
+  auto key_str = Key(key);
+  fprintf(stderr,
+          "Verification failed for column family %d key %s (%" PRIi64
+          "): value_from_db: %s, value_from_expected: %s, msg: %s\n",
+          cf, Slice(key_str).ToString(true).c_str(), key,
+          value_from_db.ToString(true).c_str(),
+          value_from_expected.ToString(true).c_str(), msg.c_str());
+  shared->SetVerificationFailure();
+}
+
 void StressTest::PrintStatistics() {
   if (dbstats) {
     fprintf(stdout, "STATISTICS:\n%s\n", dbstats->ToString().c_str());
diff --git a/db_stress_tool/db_stress_test_base.h b/db_stress_tool/db_stress_test_base.h
index 3a4b8aa57..40e4e7a92 100644
--- a/db_stress_tool/db_stress_test_base.h
+++ b/db_stress_tool/db_stress_test_base.h
@@ -222,6 +222,10 @@ class StressTest {
   void VerificationAbort(SharedState* shared, std::string msg, int cf,
                          int64_t key) const;
 
+  void VerificationAbort(SharedState* shared, std::string msg, int cf,
+                         int64_t key, Slice value_from_db,
+                         Slice value_from_expected) const;
+
   void PrintEnv() const;
 
   void Open(SharedState* shared);
diff --git a/db_stress_tool/no_batched_ops_stress.cc b/db_stress_tool/no_batched_ops_stress.cc
index 2792cd98a..38ef31f4e 100644
--- a/db_stress_tool/no_batched_ops_stress.cc
+++ b/db_stress_tool/no_batched_ops_stress.cc
@@ -1264,22 +1264,27 @@ class NonBatchedOpsStressTest : public StressTest {
     if (s.ok()) {
       char value[kValueMaxLen];
       if (value_base == SharedState::DELETION_SENTINEL) {
-        VerificationAbort(shared, "Unexpected value found", cf, key);
+        VerificationAbort(shared, "Unexpected value found", cf, key,
+                          value_from_db, "");
         return false;
       }
       size_t sz = GenerateValue(value_base, value, sizeof(value));
       if (value_from_db.length() != sz) {
-        VerificationAbort(shared, "Length of value read is not equal", cf, key);
+        VerificationAbort(shared, "Length of value read is not equal", cf, key,
+                          value_from_db, Slice(value, sz));
         return false;
       }
       if (memcmp(value_from_db.data(), value, sz) != 0) {
-        VerificationAbort(shared, "Contents of value read don't match", cf,
-                          key);
+        VerificationAbort(shared, "Contents of value read don't match", cf, key,
+                          value_from_db, Slice(value, sz));
         return false;
       }
     } else {
       if (value_base != SharedState::DELETION_SENTINEL) {
-        VerificationAbort(shared, "Value not found: " + s.ToString(), cf, key);
+        char value[kValueMaxLen];
+        size_t sz = GenerateValue(value_base, value, sizeof(value));
+        VerificationAbort(shared, "Value not found: " + s.ToString(), cf, key,
+                          "", Slice(value, sz));
         return false;
       }
     }