1 files changed, 53 insertions, 0 deletions
diff --git a/src/blockchain_db/locked_txn.h b/src/blockchain_db/locked_txn.h
new file mode 100644
index 000000000..d14631ddb
--- /dev/null
+++ b/src/blockchain_db/locked_txn.h
@@ -0,0 +1,53 @@
+// Copyright (c) 2014-2019, The Monero Project
+//
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without modification, are
+// permitted provided that the following conditions are met:
+//
+// 1. Redistributions of source code must retain the above copyright notice, this list of
+//    conditions and the following disclaimer.
+//
+// 2. Redistributions in binary form must reproduce the above copyright notice, this list
+//    of conditions and the following disclaimer in the documentation and/or other
+//    materials provided with the distribution.
+//
+// 3. Neither the name of the copyright holder nor the names of its contributors may be
+//    used to endorse or promote products derived from this software without specific
+//    prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY
+// EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL
+// THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+// PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+// STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
+// THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+//
+// Parts of this file are originally copyright (c) 2012-2013 The Cryptonote developers
+
+#pragma once
+
+namespace cryptonote
+{
+    // This class is meant to create a batch when none currently exists.
+    // If a batch exists, it can't be from another thread, since we can
+    // only be called with the txpool lock taken, and it is held during
+    // the whole prepare/handle/cleanup incoming block sequence.
+    class LockedTXN {
+    public:
+      LockedTXN(BlockchainDB &db): m_db(db), m_batch(false), m_active(false) {
+        m_batch = m_db.batch_start();
+        m_active = true;
+      }
+      void commit() { try { if (m_batch && m_active) { m_db.batch_stop(); m_active = false; } } catch (const std::exception &e) { MWARNING("LockedTXN::commit filtering exception: " << e.what()); } }
+      void abort() { try { if (m_batch && m_active) { m_db.batch_abort(); m_active = false; } } catch (const std::exception &e) { MWARNING("LockedTXN::abort filtering exception: " << e.what()); } }
+      ~LockedTXN() { abort(); }
+    private:
+      BlockchainDB &m_db;
+      bool m_batch;
+      bool m_active;
+    };
+}