Pass victim context for provider on BF abort

This change is needed for custom provider implementations to
have a way to access the victim in the application context.

Helper interface operation_context to pass caller context for
service/provider callbacks in more type safe way.

include/wsrep/client_state.hpp

@@ -43,6 +43,7 @@
 #include "thread.hpp"
 #include "xid.hpp"
 #include "chrono.hpp"
+#include "operation_context.hpp"
 
 namespace wsrep
 {
@@ -662,22 +663,45 @@ namespace wsrep
          * called by a transaction which needs to BF abort a conflicting
          * locally processing transaction.
          */
-        int bf_abort(wsrep::seqno bf_seqno)
+        int bf_abort(wsrep::seqno bf_seqno,
+                     wsrep::operation_context& victim_ctx)
         {
             wsrep::unique_lock<wsrep::mutex> lock(mutex_);
             assert(mode_ == m_local || transaction_.is_streaming());
-            return transaction_.bf_abort(lock, bf_seqno);
+            return transaction_.bf_abort(lock, bf_seqno, victim_ctx);
+        }
+
+        /**
+         * For backwards compatibility when the caller does not pass
+         * victim_ctx.
+         */
+        int bf_abort(wsrep::seqno bf_seqno)
+        {
+            wsrep::null_operation_context victim_ctx;
+            return bf_abort(bf_seqno, victim_ctx);
         }
         /**
          * Brute force abort a transaction in total order. This method
          * should be called by the TOI operation which needs to
          * BF abort a transaction.
          */
-        int total_order_bf_abort(wsrep::seqno bf_seqno)
+        int total_order_bf_abort(wsrep::seqno bf_seqno,
+                                 wsrep::operation_context& victim_ctx)
         {
             wsrep::unique_lock<wsrep::mutex> lock(mutex_);
             assert(mode_ == m_local || transaction_.is_streaming());
-            return transaction_.total_order_bf_abort(lock, bf_seqno);
+            return transaction_.total_order_bf_abort(lock, bf_seqno,
+                                                     victim_ctx);
+        }
+
+        /**
+         * For backwards compatibility when the caller does not pass
+         * victim_ctx.
+         */
+        int total_order_bf_abort(wsrep::seqno bf_seqno)
+        {
+            wsrep::null_operation_context victim_ctx;
+            return total_order_bf_abort(bf_seqno, victim_ctx);
         }
 
         /**

include/wsrep/operation_context.hpp

@@ -0,0 +1,41 @@
+/*
+ * Copyright (C) 2022 Codership Oy <info@codership.com>
+ *
+ * This file is part of wsrep-lib.
+ *
+ * Wsrep-lib is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * Wsrep-lib is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with wsrep-lib.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+/** @file operation_context.hpp
+ *
+ * A slightly more type safe way compared to void pointers to
+ * pass operation contexts through wsrep-lib to callbacks.
+ */
+
+#ifndef WSREP_OPERATION_CONTEXT_HPP
+#define WSREP_OPERATION_CONTEXT_HPP
+
+namespace wsrep
+{
+    struct operation_context
+    {
+        virtual ~operation_context() = default;
+    };
+
+    struct null_operation_context : operation_context
+    {
+    };
+} // namespace wsrep
+
+#endif /* WSREP_OPERATION_CONTEXT_HPP */

include/wsrep/provider.hpp

@@ -26,6 +26,7 @@
 #include "client_id.hpp"
 #include "transaction_id.hpp"
 #include "compiler.hpp"
+#include "operation_context.hpp"
 
 #include <cassert>
 #include <cstring>
@@ -342,6 +343,7 @@ namespace wsrep
          */
         virtual enum status bf_abort(wsrep::seqno bf_seqno,
                                      wsrep::transaction_id victim_trx,
+                                     wsrep::operation_context& victim_ctx,
                                      wsrep::seqno& victim_seqno) = 0;
         virtual enum status rollback(wsrep::transaction_id) = 0;
         virtual enum status commit_order_enter(const wsrep::ws_handle&,

include/wsrep/transaction.hpp

@@ -30,6 +30,7 @@
 #include "buffer.hpp"
 #include "client_service.hpp"
 #include "xid.hpp"
+#include "operation_context.hpp"
 
 #include <cassert>
 #include <vector>
@@ -199,9 +200,11 @@ namespace wsrep
         void after_applying();
 
         bool bf_abort(wsrep::unique_lock<wsrep::mutex>& lock,
-                      wsrep::seqno bf_seqno);
+                      wsrep::seqno bf_seqno,
+                      wsrep::operation_context&);
         bool total_order_bf_abort(wsrep::unique_lock<wsrep::mutex>&,
-                                  wsrep::seqno bf_seqno);
+                                  wsrep::seqno bf_seqno,
+                                  wsrep::operation_context&);
 
         void clone_for_replay(const wsrep::transaction& other);