/*******************************************************************//**
Stores info of an undo log record during a purge.
@return pointer to the storage cell */
static
trx_undo_inf_t*
trx_purge_arr_store_info(
/*=====================*/
trx_id_t trx_no, /*!< in: transaction number */
undo_no_t undo_no)/*!< in: undo number */
{
trx_undo_inf_t* cell;
trx_undo_arr_t* arr;
ulint i;
arr = purge_sys->arr;
for (i = 0;; i++) {
cell = trx_undo_arr_get_nth_info(arr, i);
if (!(cell->in_use)) {
/* Not in use, we may store here */
cell->undo_no = undo_no;
cell->trx_no = trx_no;
cell->in_use = TRUE;
arr->n_used++;
return(cell);
}
}
}
/*******************************************************************//**
Gets the biggest pair of a trx number and an undo number in a purge array. */
static
void
trx_purge_arr_get_biggest(
/*======================*/
trx_undo_arr_t* arr, /*!< in: purge array */
trx_id_t* trx_no, /*!< out: transaction number: ut_dulint_zero
if array is empty */
undo_no_t* undo_no)/*!< out: undo number */
{
trx_undo_inf_t* cell;
trx_id_t pair_trx_no;
undo_no_t pair_undo_no;
int trx_cmp;
ulint n_used;
ulint i;
ulint n;
n = 0;
n_used = arr->n_used;
pair_trx_no = ut_dulint_zero;
pair_undo_no = ut_dulint_zero;
for (i = 0;; i++) {
cell = trx_undo_arr_get_nth_info(arr, i);
if (cell->in_use) {
n++;
trx_cmp = ut_dulint_cmp(cell->trx_no, pair_trx_no);
if ((trx_cmp > 0)
|| ((trx_cmp == 0)
&& (ut_dulint_cmp(cell->undo_no,
pair_undo_no) >= 0))) {
pair_trx_no = cell->trx_no;
pair_undo_no = cell->undo_no;
}
}
if (n == n_used) {
*trx_no = pair_trx_no;
*undo_no = pair_undo_no;
return;
}
}
}
/*******************************************************************//**
Gets the biggest pair of a trx number and an undo number in a purge array. */
static
void
trx_purge_arr_get_biggest(
/*======================*/
trx_undo_arr_t* arr, /*!< in: purge array */
trx_id_t* trx_no, /*!< out: transaction number: 0
if array is empty */
undo_no_t* undo_no)/*!< out: undo number */
{
trx_undo_inf_t* cell;
trx_id_t pair_trx_no;
undo_no_t pair_undo_no;
ulint i;
ulint n;
n = arr->n_used;
pair_trx_no = 0;
pair_undo_no = 0;
if (n) {
for (i = 0;; i++) {
cell = trx_undo_arr_get_nth_info(arr, i);
if (!cell->in_use) {
continue;
}
if ((cell->trx_no > pair_trx_no)
|| ((cell->trx_no == pair_trx_no)
&& cell->undo_no >= pair_undo_no)) {
pair_trx_no = cell->trx_no;
pair_undo_no = cell->undo_no;
}
if (!--n) {
break;
}
}
}
*trx_no = pair_trx_no;
*undo_no = pair_undo_no;
}
