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

Copyright (c) 1995, 2012, Oracle and/or its affiliates. All Rights Reserved.
Copyright (c) 2013, 2017, MariaDB Corporation.

This program is free software; you can redistribute it and/or modify it under
the terms of the GNU General Public License as published by the Free Software
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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 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/fsp0fsp.ic
File space management

Created 12/18/1995 Heikki Tuuri
*******************************************************/

#ifndef UNIV_INNOCHECKSUM

/***********************************************************************//**
Checks if a page address is an extent descriptor page address.
@return	TRUE if a descriptor page */
UNIV_INLINE
ibool
fsp_descr_page(
/*===========*/
	ulint	zip_size,/*!< in: compressed page size in bytes;
			0 for uncompressed pages */
	ulint	page_no)/*!< in: page number */
{
	ut_ad(ut_is_2pow(zip_size));

	if (!zip_size) {
		return((page_no & (UNIV_PAGE_SIZE - 1)) == FSP_XDES_OFFSET);
	}

	return((page_no & (zip_size - 1)) == FSP_XDES_OFFSET);
}

/********************************************************************//**
Determine if the tablespace is compressed from dict_table_t::flags.
@return	TRUE if compressed, FALSE if not compressed */
UNIV_INLINE
ibool
fsp_flags_is_compressed(
/*====================*/
	ulint	flags)	/*!< in: tablespace flags */
{
	return(FSP_FLAGS_GET_ZIP_SSIZE(flags) != 0);
}

#endif /* !UNIV_INNOCHECKSUM */

/********************************************************************//**
Extract the zip size from tablespace flags.
@return	compressed page size of the file-per-table tablespace in bytes,
or zero if the table is not compressed. */
UNIV_INLINE
ulint
fsp_flags_get_zip_size(
/*===================*/
	ulint	flags)	/*!< in: tablespace flags */
{
	ulint	zip_size = 0;
	ulint	ssize = FSP_FLAGS_GET_ZIP_SSIZE(flags);

	/* Convert from a 'log2 minus 9' to a page size in bytes. */
	if (ssize) {
		zip_size = ((UNIV_ZIP_SIZE_MIN >> 1) << ssize);

		ut_ad(zip_size <= UNIV_ZIP_SIZE_MAX);
	}

	return(zip_size);
}

/********************************************************************//**
Extract the page size from tablespace flags.
@return	page size of the tablespace in bytes */
UNIV_INLINE
ulint
fsp_flags_get_page_size(
/*====================*/
	ulint	flags)		/*!< in: tablespace flags */
{
	ulint   page_size = 0;
	ulint   ssize = FSP_FLAGS_GET_PAGE_SSIZE(flags);

	/* Convert from a 'log2 minus 9' to a page size in bytes. */
	if (UNIV_UNLIKELY(ssize)) {
		page_size = ((UNIV_ZIP_SIZE_MIN >> 1) << ssize);

		ut_ad(page_size <= UNIV_PAGE_SIZE_MAX);
	} else {
		/* If the page size was not stored, then it is the
		original 16k. */
		page_size = UNIV_PAGE_SIZE_ORIG;
	}

	return(page_size);
}

#ifndef UNIV_INNOCHECKSUM
/********************************************************************//**
Calculates the descriptor index within a descriptor page.
@return	descriptor index */
UNIV_INLINE
ulint
xdes_calc_descriptor_index(
/*=======================*/
	ulint	zip_size,	/*!< in: compressed page size in bytes;
				0 for uncompressed pages */
	ulint	offset)		/*!< in: page offset */
{
	ut_ad(ut_is_2pow(zip_size));

	if (zip_size == 0) {
		return(ut_2pow_remainder(offset, UNIV_PAGE_SIZE)
		       / FSP_EXTENT_SIZE);
	} else {
		return(ut_2pow_remainder(offset, zip_size) / FSP_EXTENT_SIZE);
	}
}
#endif /* !UNIV_INNOCHECKSUM */

/**********************************************************************//**
Gets a descriptor bit of a page.
@return	TRUE if free */
UNIV_INLINE
ibool
xdes_get_bit(
/*=========*/
	const xdes_t*	descr,	/*!< in: descriptor */
	ulint		bit,	/*!< in: XDES_FREE_BIT or XDES_CLEAN_BIT */
	ulint		offset)	/*!< in: page offset within extent:
				0 ... FSP_EXTENT_SIZE - 1 */
{
	ut_ad(offset < FSP_EXTENT_SIZE);
	ut_ad(bit == XDES_FREE_BIT || bit == XDES_CLEAN_BIT);

	ulint	index = bit + XDES_BITS_PER_PAGE * offset;

	ulint	bit_index = index % 8;
	ulint	byte_index = index / 8;

	return(ut_bit_get_nth(
			mach_read_ulint(descr + XDES_BITMAP + byte_index,
					MLOG_1BYTE),
			bit_index));
}

#ifndef UNIV_INNOCHECKSUM
/********************************************************************//**
Calculates the page where the descriptor of a page resides.
@return	descriptor page offset */
UNIV_INLINE
ulint
xdes_calc_descriptor_page(
/*======================*/
	ulint	zip_size,	/*!< in: compressed page size in bytes;
				0 for uncompressed pages */
	ulint	offset)		/*!< in: page offset */
{
#ifndef DOXYGEN /* Doxygen gets confused by these */
# if UNIV_PAGE_SIZE_MAX <= XDES_ARR_OFFSET				\
			   + (UNIV_PAGE_SIZE_MAX / FSP_EXTENT_SIZE_MAX)	\
			   * XDES_SIZE_MAX
#  error
# endif
# if UNIV_ZIP_SIZE_MIN <= XDES_ARR_OFFSET				\
			  + (UNIV_ZIP_SIZE_MIN / FSP_EXTENT_SIZE_MIN)	\
			  * XDES_SIZE_MIN
#  error
# endif
#endif /* !DOXYGEN */

	ut_ad(UNIV_PAGE_SIZE > XDES_ARR_OFFSET
	      + (UNIV_PAGE_SIZE / FSP_EXTENT_SIZE)
	      * XDES_SIZE);
	ut_ad(UNIV_ZIP_SIZE_MIN > XDES_ARR_OFFSET
	      + (UNIV_ZIP_SIZE_MIN / FSP_EXTENT_SIZE)
	      * XDES_SIZE);

	ut_ad(ut_is_2pow(zip_size));

	if (zip_size == 0) {
		return(ut_2pow_round(offset, UNIV_PAGE_SIZE));
	} else {
		ut_ad(zip_size > XDES_ARR_OFFSET
		      + (zip_size / FSP_EXTENT_SIZE) * XDES_SIZE);
		return(ut_2pow_round(offset, zip_size));
	}
}

#endif /* !UNIV_INNOCHECKSUM */