Function update_role_columns

sql/sql_acl.cc:6942–6997

merges column privileges for the entry 'merged' @param merged GRANT_TABLE to merge the privileges into @param cur first entry in the array of GRANT_TABLE's for a given table @param last last entry in the array of GRANT_TABLE's for a given table, all entries between cur and last correspond to the *same* table @return 1 if the _set of columns_ in 'merged' was changed

          (not if the _set of privileges_ was changed).
*/
static int update_role_columns(GRANT_TABLE *merged,
                               GRANT_TABLE **cur, GRANT_TABLE **last)
{
  privilege_t rights __attribute__((unused)) (NO_ACL);
  int changed= 0;
  if (!merged->cols)
  {
    changed= merged->hash_columns.records > 0;
    my_hash_reset(&merged->hash_columns);
    return changed;
  }

  DBUG_EXECUTE_IF("role_merge_stats", role_column_merges++;);

  HASH *mh= &merged->hash_columns;
  for (uint i=0 ; i < mh->records ; i++)
  {
    GRANT_COLUMN *col = (GRANT_COLUMN *)my_hash_element(mh, i);
    col->rights= col->init_rights;
  }

  for (; cur < last; cur++)
  {
    if (*cur == merged)
      continue;
    HASH *ch= &cur[0]->hash_columns;
    for (uint i=0 ; i < ch->records ; i++)
    {
      GRANT_COLUMN *ccol = (GRANT_COLUMN *)my_hash_element(ch, i);
      GRANT_COLUMN *mcol = (GRANT_COLUMN *)my_hash_search(mh,
                                  (uchar *)ccol->column, ccol->key_length);
      if (mcol)
        mcol->rights|= ccol->rights;
      else
      {
        changed= 1;
        my_hash_insert(mh, (uchar*)new (&grant_memroot) GRANT_COLUMN(ccol));
      }
    }
  }

restart:
  for (uint i=0 ; i < mh->records ; i++)
  {
    GRANT_COLUMN *col = (GRANT_COLUMN *)my_hash_element(mh, i);
    rights|= col->rights;
    if (!col->rights)
    {
      changed= 1;
      my_hash_delete(mh, (uchar*)col);
      goto restart;
    }
  }
  DBUG_ASSERT(rights == merged->cols);
  return changed;
}

/**