Function enumerate_sys_vars

sql/set_var.cc:432–475

*/

SHOW_VAR* enumerate_sys_vars(THD *thd, bool sorted, enum enum_var_type type)
{
  int count= system_variable_hash.records, i;
  int size= sizeof(SHOW_VAR) * (count + 1);
  SHOW_VAR *result= (SHOW_VAR*) thd->alloc(size);

  if (result)
  {
    SHOW_VAR *show= result;

    for (i= 0; i < count; i++)
    {
      sys_var *var= (sys_var*) my_hash_element(&system_variable_hash, i);
      const my_bool *hidden=
        getopt_constraint_get_hidden_value(var->name.str, var->name.length,
                                           FALSE);

      if (hidden && *hidden)
        continue;

      // don't show session-only variables in SHOW GLOBAL VARIABLES
      if (type == OPT_GLOBAL && var->check_type(type))
        continue;

      /* don't show non-visible variables */
      if (var->not_visible())
        continue;

      show->name= var->name.str;
      show->value= (char*) var;
      show->type= SHOW_SYS;
      show++;
    }

    /* sort into order */
    if (sorted)
      my_qsort(result, show-result, sizeof(SHOW_VAR),
               (qsort_cmp) show_cmp);

    /* make last element empty */
    memset(show, 0, sizeof(SHOW_VAR));
  }
  return result;
}

/**
  Find a user set-table variable.