/*****************************************************************************

Copyright (c) 1996, 2011, Oracle and/or its affiliates. All Rights Reserved.

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License, version 2.0,
as published by the Free Software Foundation.

This program is also distributed with certain software (including
but not limited to OpenSSL) that is licensed under separate terms,
as designated in a particular file or component or in included license
documentation.  The authors of MySQL hereby grant you an additional
permission to link the program and your derivative works with the
separately licensed software that they have included with MySQL.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License, version 2.0, for more details.

You should have received a copy of the GNU General Public License along with
this program; if not, write to the Free Software Foundation, Inc.,
51 Franklin Street, Suite 500, Boston, MA 02110-1335 USA

*****************************************************************************/

/**************************************************//**
@file include/trx0trx.ic
The transaction

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

/**********************************************************************//**
Determines if a transaction is in the given state.
The caller must hold trx_sys->mutex, or it must be the thread
that is serving a running transaction.
A running transaction must be in trx_sys->ro_trx_list or trx_sys->rw_trx_list
unless it is a non-locking autocommit read only transaction, which is only
in trx_sys->mysql_trx_list.
@return	TRUE if trx->state == state */
UNIV_INLINE
ibool
trx_state_eq(
/*=========*/
	const trx_t*	trx,	/*!< in: transaction */
	trx_state_t	state)	/*!< in: state;
				if state != TRX_STATE_NOT_STARTED
				asserts that
				trx->state != TRX_STATE_NOT_STARTED */
{
#ifdef UNIV_DEBUG
	switch (trx->state) {
	case TRX_STATE_PREPARED:
		ut_ad(!trx_is_autocommit_non_locking(trx));
		return(trx->state == state);

	case TRX_STATE_ACTIVE:
		assert_trx_nonlocking_or_in_list(trx);
		return(state == trx->state);

	case TRX_STATE_COMMITTED_IN_MEMORY:
		assert_trx_in_list(trx);
		return(state == trx->state);

	case TRX_STATE_NOT_STARTED:
		/* This state is not allowed for running transactions. */
		ut_a(state == TRX_STATE_NOT_STARTED);
		ut_ad(!trx->in_rw_trx_list);
		ut_ad(!trx->in_ro_trx_list);
		return(state == trx->state);
	}
	ut_error;
#endif /* UNIV_DEBUG */
	return(trx->state == state);
}

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

/*******************************************************************//**
Retrieves transaction's que state in a human readable string. The string
should not be free()'d or modified.
@return	string in the data segment */
UNIV_INLINE
const char*
trx_get_que_state_str(
/*==================*/
	const trx_t*	trx)	/*!< in: transaction */
{
	/* be sure to adjust TRX_QUE_STATE_STR_MAX_LEN if you change this */
	switch (trx->lock.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");
	}
}

/**********************************************************************//**
Determine if a transaction is a dictionary operation.
@return	dictionary operation mode */
UNIV_INLINE
enum trx_dict_op_t
trx_get_dict_operation(
/*===================*/
	const trx_t*	trx)	/*!< in: transaction */
{
	trx_dict_op_t op = static_cast<trx_dict_op_t>(trx->dict_operation);

#ifdef UNIV_DEBUG
	switch (op) {
	case TRX_DICT_OP_NONE:
	case TRX_DICT_OP_TABLE:
	case TRX_DICT_OP_INDEX:
		return(op);
	}
	ut_error;
#endif /* UNIV_DEBUG */
	return(op);
}
/**********************************************************************//**
Flag a transaction a dictionary operation. */
UNIV_INLINE
void
trx_set_dict_operation(
/*===================*/
	trx_t*			trx,	/*!< in/out: transaction */
	enum trx_dict_op_t	op)	/*!< in: operation, not
					TRX_DICT_OP_NONE */
{
#ifdef UNIV_DEBUG
	enum trx_dict_op_t	old_op = trx_get_dict_operation(trx);

	switch (op) {
	case TRX_DICT_OP_NONE:
		ut_error;
		break;
	case TRX_DICT_OP_TABLE:
		switch (old_op) {
		case TRX_DICT_OP_NONE:
		case TRX_DICT_OP_INDEX:
		case TRX_DICT_OP_TABLE:
			goto ok;
		}
		ut_error;
		break;
	case TRX_DICT_OP_INDEX:
		ut_ad(old_op == TRX_DICT_OP_NONE);
		break;
	}
ok:
#endif /* UNIV_DEBUG */

	trx->ddl = true;
	trx->dict_operation = op;
}

/********************************************************************//**
In XtraDB it is impossible for a transaction to own a search latch outside of
InnoDB code, so there is nothing to release on demand.  We keep this function to
simplify maintenance.*/
UNIV_INLINE
void
trx_search_latch_release_if_reserved(
/*=================================*/
	trx_t*	   trx MY_ATTRIBUTE((unused))) /*!< in: transaction */
{
	ut_ad(!trx->has_search_latch);
}