Bug#36313793 Remove double unpack of ndb_apply_status event [1/3]

In preparation of Bug#36313793 ndb-log-apply-status fails to work with
no replicated changes in BI.

Handling the ndb_apply_status updates start with unpacking the whole
record just to have access to two variables for assertment. The record
is unpacked once again when handling the I/U/D.

This patch removes the double unpack of the ndb_apply_status table
event, extracting these two values directly. Adds some DBUG_PRINTS to
track the handling of ndb_apply_status updates.

Change-Id: I3f280232808bac27cfec13a6df8c710a48599b21

Author: dtcpatricio

storage/ndb/plugin/ha_ndbcluster_binlog.cc

@@ -6269,27 +6269,18 @@ int Ndb_binlog_thread::handle_data_event(const NdbEventOperation *pOp,
       const NDBEVENT::TableEvent event_type = pOp->getEventType();
       if (event_type == NDBEVENT::TE_INSERT ||
           event_type == NDBEVENT::TE_UPDATE) {
-        // Initialize "unused_bitmap" which is an output parameter from
-        // handle_data_unpack_record, afterwards it's not used which means it
-        // need not be initialized with anything useful
-        MY_BITMAP unused_bitmap;
-        Ndb_bitmap_buf<NDB_MAX_ATTRIBUTES_IN_TABLE> unused_bitbuf;
-        ndb_bitmap_init(&unused_bitmap, unused_bitbuf, table->s->fields);
-
-        // Unpack data event on mysql.ndb_apply_status to get orig_server_id
-        // and orig_epoch
-        handle_data_unpack_record(table, event_data->ndb_value[0].get(),
-                                  &unused_bitmap, table->record[0]);
-
-        // Assume that mysql.ndb_apply_status table has two fields (which should
-        // thus have been unpacked)
-        ndbcluster::ndbrequire(table->field[0] != nullptr &&
-                               table->field[1] != nullptr);
-
-        const Uint32 orig_server_id =
-            (Uint32) static_cast<Field_long *>(table->field[0])->val_int();
-        const Uint64 orig_epoch =
-            static_cast<Field_longlong *>(table->field[1])->val_int();
+        const Uint32 orig_server_id = event_data->unpack_uint32(0);
+        const Uint64 orig_epoch = event_data->unpack_uint64(1);
+
+        DBUG_PRINT("info", ("ndb_apply_status from logging_server_id: %d",
+                            logging_server_id));
+        DBUG_PRINT("info", ("  orig_server_id: %u", orig_server_id));
+        DBUG_PRINT("info", ("  orig_epoch: %llu", orig_epoch));
+        DBUG_PRINT("info",
+                   ("  log_name: '%s'", event_data->unpack_string(2) + 1));
+
+        DBUG_PRINT("info", ("  start_pos: %u", event_data->unpack_uint32(3)));
+        DBUG_PRINT("info", ("  end_pos: %u", event_data->unpack_uint32(4)));
 
         if (opt_ndb_log_apply_status) {
           /*

storage/ndb/plugin/ndb_event_data.cc

@@ -267,6 +267,10 @@ uint32 Ndb_event_data::unpack_uint32(unsigned attr_id) const {
   return ndb_value[0][attr_id].rec->u_32_value();
 }
 
+uint64 Ndb_event_data::unpack_uint64(unsigned attr_id) const {
+  return ndb_value[0][attr_id].rec->u_64_value();
+}
+
 const char *Ndb_event_data::unpack_string(unsigned attr_id) const {
   return ndb_value[0][attr_id].rec->aRef();
 }

storage/ndb/plugin/ndb_event_data.h

@@ -121,6 +121,8 @@ class Ndb_event_data {
 
   // Read uint32 value directly from NdbRecAttr in received event
   uint32 unpack_uint32(unsigned attr_id) const;
+  // Read uint64 value directly from NdbRecAttr in received event
+  uint64 unpack_uint64(unsigned attr_id) const;
   // Read string value directly from NdbRecAttr in received event
   const char *unpack_string(unsigned attr_id) const;
 

storage/ndb/src/ndbapi/NdbEventOperationImpl.cpp

@@ -1732,7 +1732,7 @@ NdbEventOperationImpl *NdbEventBuffer::getEpochEventOperations(
       event_types = gci_op.event_types;
       cumulative_any_value = gci_op.cumulative_any_value;
       filtered_any_value = gci_op.filtered_any_value;
-      DBUG_PRINT("info", ("gci: %u  op: %p  event_types: 0x%lx"
+      DBUG_PRINT("info", ("gci: %u  op: %p  event_types: 0x%lx "
                           "cumulative_any_value: 0x%lx "
                           "reference: '0x%x %s'",
                           (unsigned)epoch->m_gci.getGCI(), gci_op.op,