wallet: simplify EraseRecords by using 'ErasePrefix'

Author: furszy

src/wallet/walletdb.cpp

@@ -1230,9 +1230,8 @@ DBErrors WalletBatch::LoadWallet(CWallet* pwallet)
     return result;
 }
 
-bool RunWithinTxn(WalletDatabase& database, std::string_view process_desc, const std::function<bool(WalletBatch&)>& func)
+static bool RunWithinTxn(WalletBatch& batch, std::string_view process_desc, const std::function<bool(WalletBatch&)>& func)
 {
-    WalletBatch batch(database);
     if (!batch.TxnBegin()) {
         LogPrint(BCLog::WALLETDB, "Error: cannot create db txn for %s\n", process_desc);
         return false;
@@ -1254,6 +1253,12 @@ bool RunWithinTxn(WalletDatabase& database, std::string_view process_desc, const
     return true;
 }
 
+bool RunWithinTxn(WalletDatabase& database, std::string_view process_desc, const std::function<bool(WalletBatch&)>& func)
+{
+    WalletBatch batch(database);
+    return RunWithinTxn(batch, process_desc, func);
+}
+
 void MaybeCompactWalletDB(WalletContext& context)
 {
     static std::atomic<bool> fOneThread(false);
@@ -1316,47 +1321,11 @@ bool WalletBatch::WriteWalletFlags(const uint64_t flags)
 
 bool WalletBatch::EraseRecords(const std::unordered_set<std::string>& types)
 {
-    // Begin db txn
-    if (!m_batch->TxnBegin()) return false;
-
-    // Get cursor
-    std::unique_ptr<DatabaseCursor> cursor = m_batch->GetNewCursor();
-    if (!cursor)
-    {
-        return false;
-    }
-
-    // Iterate the DB and look for any records that have the type prefixes
-    while (true) {
-        // Read next record
-        DataStream key{};
-        DataStream value{};
-        DatabaseCursor::Status status = cursor->Next(key, value);
-        if (status == DatabaseCursor::Status::DONE) {
-            break;
-        } else if (status == DatabaseCursor::Status::FAIL) {
-            cursor.reset(nullptr);
-            m_batch->TxnAbort(); // abort db txn
-            return false;
-        }
-
-        // Make a copy of key to avoid data being deleted by the following read of the type
-        const SerializeData key_data{key.begin(), key.end()};
-
-        std::string type;
-        key >> type;
-
-        if (types.count(type) > 0) {
-            if (!m_batch->Erase(Span{key_data})) {
-                cursor.reset(nullptr);
-                m_batch->TxnAbort();
-                return false; // erase failed
-            }
-        }
-    }
-    // Finish db txn
-    cursor.reset(nullptr);
-    return m_batch->TxnCommit();
+    return RunWithinTxn(*this, "erase records", [&types](WalletBatch& self) {
+        return std::all_of(types.begin(), types.end(), [&self](const std::string& type) {
+            return self.m_batch->ErasePrefix(DataStream() << type);
+        });
+    });
 }
 
 bool WalletBatch::TxnBegin()