[fixup] post-merge spider fixup

MDEV-32524: a couple missed magic numbers
MDEV-26247: a couple missed goto statements that could lead to memory leak

Author: mariadb-YuchenPei

storage/spider/spd_db_conn.cc

@@ -4786,7 +4786,7 @@ int spider_db_store_result_for_reuse_cursor(
       THD *thd = current_thd;
       char buf[MAX_FIELD_WIDTH];
       spider_string tmp_str(buf, MAX_FIELD_WIDTH, &my_charset_bin);
-      tmp_str.init_calc_mem(120);
+      tmp_str.init_calc_mem(SPD_MID_DB_STORE_RESULT_FOR_REUSE_CURSOR_1);
 
       DBUG_PRINT("info",("spider store result to temporary table"));
       DBUG_ASSERT(!current->result_tmp_tbl);

storage/spider/spd_db_mysql.cc

@@ -3364,7 +3364,7 @@ int spider_db_mbase::set_loop_check(
   spider_string sql_str(sql_buf, sizeof(sql_buf), &my_charset_bin);
   DBUG_ENTER("spider_db_mbase::set_loop_check");
   DBUG_PRINT("info",("spider this=%p", this));
-  sql_str.init_calc_mem(270);
+  sql_str.init_calc_mem(SPD_MID_DB_MBASE_SET_LOOP_CHECK_1);
   while ((lcptr = (SPIDER_CONN_LOOP_CHECK *) my_hash_element(
     &conn->loop_check_queue, 0)))
   {

storage/spider/spd_group_by_handler.cc

@@ -1719,8 +1719,7 @@ group_by_handler *spider_create_group_by_handler(
   if (spider->dml_init())
   {
     DBUG_PRINT("info",("spider can not init for dml"));
-    delete fields;
-    DBUG_RETURN(NULL);
+    goto skip_free_fields;
   }
   for (
     roop_count = spider_conn_link_idx_next(share->link_statuses,
@@ -1792,8 +1791,7 @@ group_by_handler *spider_create_group_by_handler(
     if (spider->dml_init())
     {
       DBUG_PRINT("info",("spider can not init for dml"));
-      delete fields;
-      DBUG_RETURN(NULL);
+      goto skip_free_fields;
     }
     for (
       roop_count = spider_conn_link_idx_next(share->link_statuses,

storage/spider/spd_include.h

@@ -377,6 +377,7 @@ enum spider_malloc_id {
   SPD_MID_DB_MBASE_RESULT_FETCH_ROW_FROM_TMP_TABLE_3,
   SPD_MID_DB_MBASE_ROW_APPEND_ESCAPED_TO_STR_1,
   SPD_MID_DB_MBASE_ROW_CLONE_1,
+  SPD_MID_DB_MBASE_SET_LOOP_CHECK_1,
   SPD_MID_DB_MBASE_SET_SQL_MODE_1,
   SPD_MID_DB_MBASE_SET_TIME_ZONE_1,
   SPD_MID_DB_MBASE_SET_WAIT_TIMEOUT_1,
@@ -412,6 +413,7 @@ enum spider_malloc_id {
   SPD_MID_DB_STORE_RESULT_3,
   SPD_MID_DB_STORE_RESULT_4,
   SPD_MID_DB_STORE_RESULT_5,
+  SPD_MID_DB_STORE_RESULT_FOR_REUSE_CURSOR_1,
   SPD_MID_DB_UDF_COPY_TABLES_1,
   SPD_MID_DB_UDF_PING_TABLE_1,
   SPD_MID_DB_UDF_PING_TABLE_2,