Mysql源码学习——没那么简单的Hash(10)

                    if (!(flag & LOWUSED))

                    {

                        /* Change link of previous LOW-key */

                        gpos->data=ptr_to_rec;

                        gpos->next= (uint) (pos-data);

                        flag= (flag & HIGHFIND) | (LOWFIND | LOWUSED);

                    }

                    gpos=pos;

                    ptr_to_rec=pos->data;

                }

            }

            else

            {                       /* key will be moved */

                if (!(flag & HIGHFIND))

                {

                    flag= (flag & LOWFIND) | HIGHFIND;

                    /* key shall be moved to the last (empty) position */

                    gpos2 = empty; empty=pos;

                    ptr_to_rec2=pos->data;

                }

                else

                {