Split commit_or_rollback_by_xid() in two methods

Split `client_state::commit_or_rollback_by_xid()` into
`client_state::commit_by_xid()` and `client_state::rollback_by_xid()`.

include/wsrep/client_state.hpp

@@ -550,22 +550,39 @@ namespace wsrep
         }
 
         /**
-         * Terminate transaction with the given xid
+         * Commit transaction with the given xid
          *
-         * Sends a commit or rollback fragment to terminate a
+         * Sends a commit fragment to terminate the transaction with
-         * transaction with the given xid. For the fragment to be
+         * the given xid. For the fragment to be sent, a streaming
-         * sent, a streaming applier for the transaction must exist
+         * applier for the transaction must exist, and the transaction
-         * and the transaction must be in prepared state.
+         * must be in prepared state.
          *
-         * @param xid the xid of the the transaction to terminate
+         * @param xid the xid of the the transaction to commit
-         * @param commit whether to send a commmit or rollback fragment
          *
          * @return Zero on success, non-zero on error. In case of error
          *         the client_state's current_error is set
          */
-        int commit_or_rollback_by_xid(const std::string& xid, bool commit)
+        int commit_by_xid(const std::string& xid)
         {
-            return transaction_.commit_or_rollback_by_xid(xid, commit);
+            return transaction_.commit_or_rollback_by_xid(xid, true);
+        }
+
+        /**
+         * Rollback transaction with the given xid
+         *
+         * Sends a rollback fragment to terminate the transaction with
+         * the given xid. For the fragment to be sent, a streaming
+         * applier for the transaction must exist, and the transaction
+         * must be in prepared state.
+         *
+         * @param xid the xid of the the transaction to commit
+         *
+         * @return Zero on success, non-zero on error. In case of error
+         *         the client_state's current_error is set
+         */
+        int rollback_by_xid(const std::string& xid)
+        {
+            return transaction_.commit_or_rollback_by_xid(xid, false);
         }
 
         //

src/transaction.cpp

@@ -1209,14 +1209,14 @@ int wsrep::transaction::streaming_step(wsrep::unique_lock<wsrep::mutex>& lock,
     assert(streaming_context_.fragment_size() || is_xa());
 
     if (client_service_.bytes_generated() <
-        streaming_context_.bytes_certified())
+        streaming_context_.log_position())
     {
         /* Something went wrong on DBMS side in keeping track of
            generated bytes. Return an error to abort the transaction. */
         wsrep::log_warning() << "Bytes generated "
                              << client_service_.bytes_generated()
                              << " less than bytes certified "
-                             << streaming_context_.bytes_certified()
+                             << streaming_context_.log_position()
                              << ", aborting streaming transaction";
         return 1;
     }