/******************************************************
The transaction

(c) 1996 Innobase Oy

Created 3/26/1996 Heikki Tuuri
*******************************************************/

/*****************************************************************
Starts the transaction if it is not yet started. */
UNIV_INLINE
void
trx_start_if_not_started(
/*=====================*/
	trx_t*	trx)	/* in: transaction */
{
	ut_ad(trx->conc_state != TRX_COMMITTED_IN_MEMORY);

	if (trx->conc_state == TRX_NOT_STARTED) {

		trx_start(trx, ULINT_UNDEFINED);
	}
}

/*****************************************************************
Starts the transaction if it is not yet started. Assumes we have reserved
the kernel mutex! */
UNIV_INLINE
void
trx_start_if_not_started_low(
/*=========================*/
	trx_t*	trx)	/* in: transaction */
{
	ut_ad(trx->conc_state != TRX_COMMITTED_IN_MEMORY);

	if (trx->conc_state == TRX_NOT_STARTED) {

		trx_start_low(trx, ULINT_UNDEFINED);
	}
}

/*****************************************************************
Resets the new record lock info in a transaction struct. */
UNIV_INLINE
void
trx_reset_new_rec_lock_info(
/*========================*/
	trx_t*	trx)	/* in: transaction struct */
{
	trx->new_rec_locks[0] = NULL;
	trx->new_rec_locks[1] = NULL;
}

/*****************************************************************
Registers that we have set a new record lock on an index. We only have space
to store 2 indexes! If this is called to store more than 2 indexes after
trx_reset_new_rec_lock_info(), then this function does nothing. */
UNIV_INLINE
void
trx_register_new_rec_lock(
/*======================*/
	trx_t*		trx,	/* in: transaction struct */
	dict_index_t*	index)	/* in: trx sets a new record lock on this
				index */
{
	if (trx->new_rec_locks[0] == NULL) {
		trx->new_rec_locks[0] = index;

		return;
	}

	if (trx->new_rec_locks[0] == index) {

		return;
	}

	if (trx->new_rec_locks[1] != NULL) {

		return;
	}

	trx->new_rec_locks[1] = index;
}

/*****************************************************************
Checks if trx has set a new record lock on an index. */
UNIV_INLINE
ibool
trx_new_rec_locks_contain(
/*======================*/
				/* out: TRUE if trx has set a new record lock
				on index */
	trx_t*		trx,	/* in: transaction struct */
	dict_index_t*	index)	/* in: index */
{
	return(trx->new_rec_locks[0] == index
	       || trx->new_rec_locks[1] == index);
}

/********************************************************************
Retrieves the error_info field from a trx. */
UNIV_INLINE
const dict_index_t*
trx_get_error_info(
/*===============*/
				/* out: the error info */
	const trx_t*	trx)	/* in: trx object */
{
	return(trx->error_info);
}

/***********************************************************************
Retrieves transacion's id, represented as unsigned long long. */
UNIV_INLINE
ullint
trx_get_id(
/*=======*/
				/* out: transaction's id */
	const trx_t*	trx)	/* in: transaction */
{
	return((ullint)ut_conv_dulint_to_longlong(trx->id));
}

/***********************************************************************
Retrieves transaction's que state in a human readable string. The string
should not be free()'d or modified. */
UNIV_INLINE
const char*
trx_get_que_state_str(
/*==================*/
				/* out: string in the data segment */
	const trx_t*	trx)	/* in: transaction */
{
	/* be sure to adjust TRX_QUE_STATE_STR_MAX_LEN if you change this */
	switch (trx->que_state) {
	case TRX_QUE_RUNNING:
		return("RUNNING");
	case TRX_QUE_LOCK_WAIT:
		return("LOCK WAIT");
	case TRX_QUE_ROLLING_BACK:
		return("ROLLING BACK");
	case TRX_QUE_COMMITTING:
		return("COMMITTING");
	default:
		return("UNKNOWN");
	}
}