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buf0checksum.cc
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1 /*****************************************************************************
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3 Copyright (c) 1995, 2011, Oracle and/or its affiliates. All Rights Reserved.
4 
5 This program is free software; you can redistribute it and/or modify it under
6 the terms of the GNU General Public License as published by the Free Software
7 Foundation; version 2 of the License.
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11 FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
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13 You should have received a copy of the GNU General Public License along with
14 this program; if not, write to the Free Software Foundation, Inc.,
15 51 Franklin Street, Suite 500, Boston, MA 02110-1335 USA
16 
17 *****************************************************************************/
18 
19 /**************************************************/
26 #include "univ.i"
27 #include "fil0fil.h" /* FIL_* */
28 #include "ut0crc32.h" /* ut_crc32() */
29 #include "ut0rnd.h" /* ut_fold_binary() */
30 
31 #ifndef UNIV_INNOCHECKSUM
32 
33 #include "srv0srv.h" /* SRV_CHECKSUM_* */
34 #include "buf0types.h"
35 
40 UNIV_INTERN ulong srv_checksum_algorithm = SRV_CHECKSUM_ALGORITHM_INNODB;
41 
42 #endif /* !UNIV_INNOCHECKSUM */
43 
44 /********************************************************************/
49 UNIV_INTERN
50 ib_uint32_t
51 buf_calc_page_crc32(
52 /*================*/
53  const byte* page)
54 {
55  ib_uint32_t checksum;
56 
57  /* Since the field FIL_PAGE_FILE_FLUSH_LSN, and in versions <= 4.1.x
58  FIL_PAGE_ARCH_LOG_NO_OR_SPACE_ID, are written outside the buffer pool
59  to the first pages of data files, we have to skip them in the page
60  checksum calculation.
61  We must also skip the field FIL_PAGE_SPACE_OR_CHKSUM where the
62  checksum is stored, and also the last 8 bytes of page because
63  there we store the old formula checksum. */
64 
65  checksum = ut_crc32(page + FIL_PAGE_OFFSET,
66  FIL_PAGE_FILE_FLUSH_LSN - FIL_PAGE_OFFSET)
67  ^ ut_crc32(page + FIL_PAGE_DATA,
68  UNIV_PAGE_SIZE - FIL_PAGE_DATA
69  - FIL_PAGE_END_LSN_OLD_CHKSUM);
70 
71  return(checksum);
72 }
73 
74 /********************************************************************/
79 UNIV_INTERN
80 ulint
81 buf_calc_page_new_checksum(
82 /*=======================*/
83  const byte* page)
84 {
85  ulint checksum;
86 
87  /* Since the field FIL_PAGE_FILE_FLUSH_LSN, and in versions <= 4.1.x
88  FIL_PAGE_ARCH_LOG_NO_OR_SPACE_ID, are written outside the buffer pool
89  to the first pages of data files, we have to skip them in the page
90  checksum calculation.
91  We must also skip the field FIL_PAGE_SPACE_OR_CHKSUM where the
92  checksum is stored, and also the last 8 bytes of page because
93  there we store the old formula checksum. */
94 
95  checksum = ut_fold_binary(page + FIL_PAGE_OFFSET,
96  FIL_PAGE_FILE_FLUSH_LSN - FIL_PAGE_OFFSET)
97  + ut_fold_binary(page + FIL_PAGE_DATA,
98  UNIV_PAGE_SIZE - FIL_PAGE_DATA
99  - FIL_PAGE_END_LSN_OLD_CHKSUM);
100  checksum = checksum & 0xFFFFFFFFUL;
101 
102  return(checksum);
103 }
104 
105 /********************************************************************/
113 UNIV_INTERN
114 ulint
115 buf_calc_page_old_checksum(
116 /*=======================*/
117  const byte* page)
118 {
119  ulint checksum;
120 
121  checksum = ut_fold_binary(page, FIL_PAGE_FILE_FLUSH_LSN);
122 
123  checksum = checksum & 0xFFFFFFFFUL;
124 
125  return(checksum);
126 }
127 
128 #ifndef UNIV_INNOCHECKSUM
129 
130 /********************************************************************/
133 UNIV_INTERN
134 const char*
135 buf_checksum_algorithm_name(
136 /*========================*/
137  srv_checksum_algorithm_t algo)
138 {
139  switch (algo) {
140  case SRV_CHECKSUM_ALGORITHM_CRC32:
141  case SRV_CHECKSUM_ALGORITHM_STRICT_CRC32:
142  return("crc32");
143  case SRV_CHECKSUM_ALGORITHM_INNODB:
144  case SRV_CHECKSUM_ALGORITHM_STRICT_INNODB:
145  return("innodb");
146  case SRV_CHECKSUM_ALGORITHM_NONE:
147  case SRV_CHECKSUM_ALGORITHM_STRICT_NONE:
148  return("none");
149  }
150 
151  ut_error;
152  return(NULL);
153 }
154 
155 #endif /* !UNIV_INNOCHECKSUM */