MDEV-30366 Permit bulk implementation to return ALL individual results

COM_STMT_BULK_STMT new flag to server to returns all unitary results

sql/sql_class.cc

@@ -1375,6 +1375,7 @@ void THD::init()
 
   apc_target.init(&LOCK_thd_kill);
   gap_tracker_data.init();
+  unit_results= NULL;
   DBUG_VOID_RETURN;
 }
 
@@ -8325,6 +8326,117 @@ bool Discrete_intervals_list::append(Discrete_interval *new_interval)
   DBUG_RETURN(0);
 }
 
+/*
+  indicate that unit result has to be reported
+*/
+bool THD::need_report_unit_results()
+{
+  return unit_results;
+}
+
+/*
+  Initialize unit result array
+*/
+bool THD::init_collecting_unit_results()
+{
+  if (!unit_results)
+  {
+    void *buff;
+
+    if (!(my_multi_malloc(PSI_NOT_INSTRUMENTED, MYF(MY_WME), &unit_results, sizeof(DYNAMIC_ARRAY),
+                          &buff, sizeof(unit_results_desc) * 10,
+                          NullS)) ||
+        my_init_dynamic_array2(PSI_INSTRUMENT_ME, unit_results, sizeof(unit_results_desc),
+                               buff, 10, 100, MYF(MY_WME)))
+    {
+      if (unit_results)
+        my_free(unit_results);
+      unit_results= NULL;
+      return TRUE;
+    }
+  }
+  return FALSE;
+}
+
+/*
+  remove unit result array
+*/
+void THD::stop_collecting_unit_results()
+{
+  if (unit_results)
+  {
+    delete_dynamic(unit_results);
+    my_free(unit_results);
+    unit_results= NULL;
+  }
+}
+
+
+/*
+  Add a unitary result to collection
+*/
+bool THD::collect_unit_results(ulonglong id, ulonglong affected_rows)
+{
+  if (unit_results)
+  {
+    unit_results_desc el;
+    el.generated_id= id;
+    el.affected_rows= affected_rows;
+    if (insert_dynamic(unit_results, &el))
+    {
+      return TRUE;
+    }
+  }
+  return FALSE;
+}
+
+/*
+  Write unitary result result-set WITHOUT ending EOF/OK_Packet to socket.
+*/
+bool THD::report_collected_unit_results()
+{
+  if (unit_results)
+  {
+    List<Item> field_list;
+    MEM_ROOT tmp_mem_root;
+    Query_arena arena(&tmp_mem_root, Query_arena::STMT_INITIALIZED), backup;
+
+    init_alloc_root(PSI_NOT_INSTRUMENTED, arena.mem_root, 2048, 4096, MYF(0));
+    set_n_backup_active_arena(&arena, &backup);
+    DBUG_ASSERT(mem_root == &tmp_mem_root);
+
+    field_list.push_back(new (mem_root)
+                         Item_int(this, "Id", 0, MY_INT64_NUM_DECIMAL_DIGITS),
+                         mem_root);
+    field_list.push_back(new (mem_root)
+                         Item_int(this, "Affected_rows", 0, MY_INT64_NUM_DECIMAL_DIGITS),
+                         mem_root);
+
+    if (protocol_binary.send_result_set_metadata(&field_list,
+                                                  Protocol::SEND_NUM_ROWS | Protocol::SEND_EOF))
+      goto error;
+
+    for (ulonglong i= 0; i < unit_results->elements; i++)
+    {
+      unit_results_desc *last=
+        (unit_results_desc *)dynamic_array_ptr(unit_results, i);
+      protocol_binary.prepare_for_resend();
+      protocol_binary.store_longlong(last->generated_id, TRUE);
+      protocol_binary.store_longlong(last->affected_rows, TRUE);
+      if (protocol_binary.write())
+        goto error;
+    }
+error:
+    restore_active_arena(&arena, &backup);
+    DBUG_ASSERT(arena.mem_root == &tmp_mem_root);
+    // no need free Items because they was only constants
+    free_root(arena.mem_root, MYF(0));
+    stop_collecting_unit_results();
+    return TRUE;
+  }
+  return FALSE;
+
+}
 
 void AUTHID::copy(MEM_ROOT *mem_root, const LEX_CSTRING *user_name,
                                       const LEX_CSTRING *host_name)