From 55730549afc3af18977d81bacc068bf98f9212d7 Mon Sep 17 00:00:00 2001
From: Anthony Fieroni <bvbfan@abv.bg>
Date: Thu, 30 Jan 2020 17:42:21 +0200
Subject: [PATCH] Increase attempts to database sync

Signed-off-by: Anthony Fieroni <bvbfan@abv.bg>
---
 src/claimtrie/sqlite.h | 15 +++++++++++++++
 src/claimtrie/trie.cpp |  3 +--
 src/txdb.cpp           | 14 ++++++++++----
 3 files changed, 26 insertions(+), 6 deletions(-)

diff --git a/src/claimtrie/sqlite.h b/src/claimtrie/sqlite.h
index 7f2b8d534..bb9be35c4 100644
--- a/src/claimtrie/sqlite.h
+++ b/src/claimtrie/sqlite.h
@@ -88,6 +88,21 @@ namespace sqlite
         }
         return code;
     }
+
+    inline int sync(database& db, std::size_t attempts = 200)
+    {
+        int code = SQLITE_OK;
+        for (auto i = 0u; i < attempts; ++i) {
+            code = sqlite3_wal_checkpoint_v2(db.connection().get(), nullptr, SQLITE_CHECKPOINT_FULL, nullptr, nullptr);
+            if (code != SQLITE_OK) {
+                using namespace std::chrono_literals;
+                std::this_thread::sleep_for(100ms);
+                continue;
+            }
+            break;
+        }
+        return code;
+    }
 }
 
 #endif // SQLITE_H
diff --git a/src/claimtrie/trie.cpp b/src/claimtrie/trie.cpp
index 51c0254f0..7f6449cf6 100644
--- a/src/claimtrie/trie.cpp
+++ b/src/claimtrie/trie.cpp
@@ -131,8 +131,7 @@ CClaimTrieCacheBase::~CClaimTrieCacheBase()
 bool CClaimTrie::SyncToDisk()
 {
     // alternatively, switch to full sync after we are caught up on the chain
-    auto rc = sqlite3_wal_checkpoint_v2(db.connection().get(), nullptr, SQLITE_CHECKPOINT_FULL, nullptr, nullptr);
-    return rc == SQLITE_OK;
+    return sqlite::sync(db) == SQLITE_OK;
 }
 
 bool CClaimTrie::empty() // only used for testing
diff --git a/src/txdb.cpp b/src/txdb.cpp
index 6ecc2ff71..09e7ad83c 100644
--- a/src/txdb.cpp
+++ b/src/txdb.cpp
@@ -158,8 +158,11 @@ bool CCoinsViewDB::BatchWrite(CCoinsMap &mapCoins, const uint256 &hashBlock, boo
     }
     LogPrint(BCLog::COINDB, "Committed %u changed transaction outputs (out of %u) to coin database...\n", (unsigned int)changed, (unsigned int)count);
     if (sync) {
-        auto rc = sqlite3_wal_checkpoint_v2(db.connection().get(), nullptr, SQLITE_CHECKPOINT_FULL, nullptr, nullptr);
-        return rc == SQLITE_OK;
+        auto code = sqlite::sync(db);
+        if (code != SQLITE_OK) {
+            LogPrint(BCLog::COINDB, "Error syncing coin database. SQLite error: %d\n", code);
+            return false;
+        }
     }
     return true;
 }
@@ -337,8 +340,11 @@ bool CBlockTreeDB::BatchWrite(const std::vector<std::pair<int, const CBlockFileI
     }
     // by Sync they mean disk sync:
     if (sync) {
-        auto rc = sqlite3_wal_checkpoint_v2(db.connection().get(), nullptr, SQLITE_CHECKPOINT_FULL, nullptr, nullptr);
-        return rc == SQLITE_OK;
+        auto code = sqlite::sync(db);
+        if (code != SQLITE_OK) {
+            LogPrintf("%s: Error syncing block database. SQLite error: %d\n", __func__, code);
+            return false;
+        }
     }
     return true;
 }