polardbxengine/storage/innobase/include/trx0rec.ic

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/*****************************************************************************
Copyright (c) 1996, 2018, 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
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limited to OpenSSL) that is licensed under separate terms, as designated in a
particular file or component or in included license documentation. The authors
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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 St, Fifth Floor, Boston, MA 02110-1301 USA
*****************************************************************************/
/** @file include/trx0rec.ic
Transaction undo log record
Created 3/26/1996 Heikki Tuuri
*******************************************************/
#ifndef UNIV_HOTBACKUP
/** Reads from an undo log record the record type.
@return record type */
UNIV_INLINE
ulint trx_undo_rec_get_type(
const trx_undo_rec_t *undo_rec) /*!< in: undo log record */
{
return (mach_read_from_1(undo_rec + 2) & (TRX_UNDO_CMPL_INFO_MULT - 1));
}
/** Reads from an undo log record the record compiler info.
@return compiler info */
UNIV_INLINE
ulint trx_undo_rec_get_cmpl_info(
const trx_undo_rec_t *undo_rec) /*!< in: undo log record */
{
return (mach_read_from_1(undo_rec + 2) / TRX_UNDO_CMPL_INFO_MULT);
}
/** Returns TRUE if an undo log record contains an extern storage field.
@return true if extern */
UNIV_INLINE
ibool trx_undo_rec_get_extern_storage(
const trx_undo_rec_t *undo_rec) /*!< in: undo log record */
{
if (mach_read_from_1(undo_rec + 2) & TRX_UNDO_UPD_EXTERN) {
return (TRUE);
}
return (FALSE);
}
/** Reads the undo log record number.
@return undo no */
UNIV_INLINE
undo_no_t trx_undo_rec_get_undo_no(
const trx_undo_rec_t *undo_rec) /*!< in: undo log record */
{
const byte *ptr = undo_rec + 2;
uint8_t type_cmpl = mach_read_from_1(ptr);
const bool blob_undo = type_cmpl & TRX_UNDO_MODIFY_BLOB;
if (blob_undo) {
/* The next record offset takes 2 bytes + 1 byte for
type_cmpl flag + 1 byte for the new flag. Total 4 bytes.*/
ptr = undo_rec + 4;
} else {
ptr = undo_rec + 3;
}
return (mach_u64_read_much_compressed(ptr));
}
/** Copies the undo record to the heap.
@return own: copy of undo log record */
UNIV_INLINE
trx_undo_rec_t *trx_undo_rec_copy(
const trx_undo_rec_t *undo_rec, /*!< in: undo log record */
mem_heap_t *heap) /*!< in: heap where copied */
{
ulint len;
len = mach_read_from_2(undo_rec) - ut_align_offset(undo_rec, UNIV_PAGE_SIZE);
ut_ad(len < UNIV_PAGE_SIZE);
return ((trx_undo_rec_t *)mem_heap_dup(heap, undo_rec, len));
}
#endif /* !UNIV_HOTBACKUP */