1/*****************************************************************************
2
3Copyright (c) 1996, 2014, Oracle and/or its affiliates. All Rights Reserved.
4
5This program is free software; you can redistribute it and/or modify it under
6the terms of the GNU General Public License as published by the Free Software
7Foundation; version 2 of the License.
8
9This program is distributed in the hope that it will be useful, but WITHOUT
10ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
11FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
12
13You should have received a copy of the GNU General Public License along with
14this program; if not, write to the Free Software Foundation, Inc.,
1551 Franklin Street, Fifth Floor, Boston, MA 02110-1335 USA
16
17*****************************************************************************/
18
19/**************************************************//**
20@file include/trx0rec.ic
21Transaction undo log record
22
23Created 3/26/1996 Heikki Tuuri
24*******************************************************/
25
26/**********************************************************************//**
27Reads from an undo log record the record type.
28@return record type */
29UNIV_INLINE
30ulint
31trx_undo_rec_get_type(
32/*==================*/
33	const trx_undo_rec_t*	undo_rec)	/*!< in: undo log record */
34{
35	return(mach_read_from_1(undo_rec + 2) & (TRX_UNDO_CMPL_INFO_MULT - 1));
36}
37
38/**********************************************************************//**
39Reads the undo log record number.
40@return undo no */
41UNIV_INLINE
42undo_no_t
43trx_undo_rec_get_undo_no(
44/*=====================*/
45	const trx_undo_rec_t*	undo_rec)	/*!< in: undo log record */
46{
47	const byte*	ptr;
48
49	ptr = undo_rec + 3;
50
51	return(mach_u64_read_much_compressed(ptr));
52}
53
54/***********************************************************************//**
55Copies the undo record to the heap.
56@return own: copy of undo log record */
57UNIV_INLINE
58trx_undo_rec_t*
59trx_undo_rec_copy(
60/*==============*/
61	const trx_undo_rec_t*	undo_rec,	/*!< in: undo log record */
62	mem_heap_t*		heap)		/*!< in: heap where copied */
63{
64	ulint		len;
65
66	len = mach_read_from_2(undo_rec)
67		- ut_align_offset(undo_rec, srv_page_size);
68	ut_ad(len < srv_page_size);
69	trx_undo_rec_t* rec = static_cast<trx_undo_rec_t*>(
70		mem_heap_dup(heap, undo_rec, len));
71	mach_write_to_2(rec, len);
72	return rec;
73}
74