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Diffstat (limited to 'storage/innobase/buf/buf0checksum.cc')
| -rw-r--r-- | storage/innobase/buf/buf0checksum.cc | 155 |
1 files changed, 155 insertions, 0 deletions
diff --git a/storage/innobase/buf/buf0checksum.cc b/storage/innobase/buf/buf0checksum.cc new file mode 100644 index 00000000000..ec79bbe6be9 --- /dev/null +++ b/storage/innobase/buf/buf0checksum.cc @@ -0,0 +1,155 @@ +/***************************************************************************** + +Copyright (c) 1995, 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 as published by the Free Software +Foundation; version 2 of the License. + +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 buf/buf0checksum.cc +Buffer pool checksum functions, also linked from /extra/innochecksum.cc + +Created Aug 11, 2011 Vasil Dimov +*******************************************************/ + +#include "univ.i" +#include "fil0fil.h" /* FIL_* */ +#include "ut0crc32.h" /* ut_crc32() */ +#include "ut0rnd.h" /* ut_fold_binary() */ + +#ifndef UNIV_INNOCHECKSUM + +#include "srv0srv.h" /* SRV_CHECKSUM_* */ +#include "buf0types.h" + +/** the macro MYSQL_SYSVAR_ENUM() requires "long unsigned int" and if we +use srv_checksum_algorithm_t here then we get a compiler error: +ha_innodb.cc:12251: error: cannot convert 'srv_checksum_algorithm_t*' to + 'long unsigned int*' in initialization */ +UNIV_INTERN ulong srv_checksum_algorithm = SRV_CHECKSUM_ALGORITHM_INNODB; + +#endif /* !UNIV_INNOCHECKSUM */ + +/********************************************************************//** +Calculates a page CRC32 which is stored to the page when it is written +to a file. Note that we must be careful to calculate the same value on +32-bit and 64-bit architectures. +@return checksum */ +UNIV_INTERN +ib_uint32_t +buf_calc_page_crc32( +/*================*/ + const byte* page) /*!< in: buffer page */ +{ + ib_uint32_t checksum; + + /* Since the field FIL_PAGE_FILE_FLUSH_LSN, and in versions <= 4.1.x + FIL_PAGE_ARCH_LOG_NO_OR_SPACE_ID, are written outside the buffer pool + to the first pages of data files, we have to skip them in the page + checksum calculation. + We must also skip the field FIL_PAGE_SPACE_OR_CHKSUM where the + checksum is stored, and also the last 8 bytes of page because + there we store the old formula checksum. */ + + checksum = ut_crc32(page + FIL_PAGE_OFFSET, + FIL_PAGE_FILE_FLUSH_LSN - FIL_PAGE_OFFSET) + ^ ut_crc32(page + FIL_PAGE_DATA, + UNIV_PAGE_SIZE - FIL_PAGE_DATA + - FIL_PAGE_END_LSN_OLD_CHKSUM); + + return(checksum); +} + +/********************************************************************//** +Calculates a page checksum which is stored to the page when it is written +to a file. Note that we must be careful to calculate the same value on +32-bit and 64-bit architectures. +@return checksum */ +UNIV_INTERN +ulint +buf_calc_page_new_checksum( +/*=======================*/ + const byte* page) /*!< in: buffer page */ +{ + ulint checksum; + + /* Since the field FIL_PAGE_FILE_FLUSH_LSN, and in versions <= 4.1.x + FIL_PAGE_ARCH_LOG_NO_OR_SPACE_ID, are written outside the buffer pool + to the first pages of data files, we have to skip them in the page + checksum calculation. + We must also skip the field FIL_PAGE_SPACE_OR_CHKSUM where the + checksum is stored, and also the last 8 bytes of page because + there we store the old formula checksum. */ + + checksum = ut_fold_binary(page + FIL_PAGE_OFFSET, + FIL_PAGE_FILE_FLUSH_LSN - FIL_PAGE_OFFSET) + + ut_fold_binary(page + FIL_PAGE_DATA, + UNIV_PAGE_SIZE - FIL_PAGE_DATA + - FIL_PAGE_END_LSN_OLD_CHKSUM); + checksum = checksum & 0xFFFFFFFFUL; + + return(checksum); +} + +/********************************************************************//** +In versions < 4.0.14 and < 4.1.1 there was a bug that the checksum only +looked at the first few bytes of the page. This calculates that old +checksum. +NOTE: we must first store the new formula checksum to +FIL_PAGE_SPACE_OR_CHKSUM before calculating and storing this old checksum +because this takes that field as an input! +@return checksum */ +UNIV_INTERN +ulint +buf_calc_page_old_checksum( +/*=======================*/ + const byte* page) /*!< in: buffer page */ +{ + ulint checksum; + + checksum = ut_fold_binary(page, FIL_PAGE_FILE_FLUSH_LSN); + + checksum = checksum & 0xFFFFFFFFUL; + + return(checksum); +} + +#ifndef UNIV_INNOCHECKSUM + +/********************************************************************//** +Return a printable string describing the checksum algorithm. +@return algorithm name */ +UNIV_INTERN +const char* +buf_checksum_algorithm_name( +/*========================*/ + srv_checksum_algorithm_t algo) /*!< in: algorithm */ +{ + switch (algo) { + case SRV_CHECKSUM_ALGORITHM_CRC32: + case SRV_CHECKSUM_ALGORITHM_STRICT_CRC32: + return("crc32"); + case SRV_CHECKSUM_ALGORITHM_INNODB: + case SRV_CHECKSUM_ALGORITHM_STRICT_INNODB: + return("innodb"); + case SRV_CHECKSUM_ALGORITHM_NONE: + case SRV_CHECKSUM_ALGORITHM_STRICT_NONE: + return("none"); + } + + ut_error; + return(NULL); +} + +#endif /* !UNIV_INNOCHECKSUM */ |