[MDEV-6877] Fixed Update_rows_log_event to correctly apply update log events

Update_rows_log_event must make use of the after image bitmap when
detecting which columns to update.

sql/log_event.cc

@@ -9855,12 +9855,19 @@ int Rows_log_event::do_apply_event(rpl_group_info *rgi)
       longer if slave has extra columns. 
      */ 
 
-    DBUG_PRINT_BITSET("debug", "Setting table's write_set from: %s", &m_cols);
+    DBUG_PRINT_BITSET("debug", "Setting table's read_set from: %s", &m_cols);
     
     bitmap_set_all(table->read_set);
+    if (get_general_type_code() == DELETE_ROWS_EVENT ||
+        get_general_type_code() == UPDATE_ROWS_EVENT)
+      bitmap_intersect(table->read_set,&m_cols);
+
     bitmap_set_all(table->write_set);
-    if (!get_flags(COMPLETE_ROWS_F))
-      bitmap_intersect(table->write_set,&m_cols);
+
+    /* WRITE ROWS EVENTS store the bitmap in m_cols instead of m_cols_ai */
+    MY_BITMAP *after_image= ((get_general_type_code() == UPDATE_ROWS_EVENT) ?
+                             &m_cols_ai : &m_cols);
+    bitmap_intersect(table->write_set, after_image);
 
     this->slave_exec_mode= slave_exec_mode_options; // fix the mode
 
@@ -12396,7 +12403,7 @@ Update_rows_log_event::do_exec_row(rpl_group_info *rgi)
 
   /* this also updates m_curr_row_end */
   thd_proc_info(thd, message);
-  if ((error= unpack_current_row(rgi)))
+  if ((error= unpack_current_row(rgi, &m_cols_ai)))
     goto err;
 
   /*
@@ -12429,9 +12436,15 @@ Update_rows_log_event::do_exec_row(rpl_group_info *rgi)
     goto err;
   }
 
+  // Temporary fix to find out why it fails [/Matz]
+  memcpy(m_table->read_set->bitmap, m_cols.bitmap, (m_table->read_set->n_bits + 7) / 8);
+  memcpy(m_table->write_set->bitmap, m_cols_ai.bitmap, (m_table->write_set->n_bits + 7) / 8);
+
+  m_table->mark_columns_per_binlog_row_image();
   error= m_table->file->ha_update_row(m_table->record[1], m_table->record[0]);
   if (error == HA_ERR_RECORD_IS_THE_SAME)
     error= 0;
+  m_table->default_column_bitmaps();
 
   if (invoke_triggers && !error &&
       process_triggers(TRG_EVENT_UPDATE, TRG_ACTION_AFTER, TRUE))

sql/log_event.h

@@ -4410,6 +4410,14 @@ class Rows_log_event : public Log_event
   int write_row(rpl_group_info *, const bool);
 
   // Unpack the current row into m_table->record[0]
+  int unpack_current_row(rpl_group_info *rgi, MY_BITMAP const *cols)
+  {
+    DBUG_ASSERT(m_table);
+
+    ASSERT_OR_RETURN_ERROR(m_curr_row < m_rows_end, HA_ERR_CORRUPT_EVENT);
+    return ::unpack_row(rgi, m_table, m_width, m_curr_row, cols,
+                                   &m_curr_row_end, &m_master_reclength, m_rows_end);
+  }
   int unpack_current_row(rpl_group_info *rgi)
   {
     DBUG_ASSERT(m_table);