summaryrefslogtreecommitdiffstats
path: root/sql/sp_head.h
blob: da4e5763a484822239f44ccaf9c42384592b6571 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
/* -*- C++ -*- */
/*
   Copyright (c) 2002, 2011, Oracle and/or its affiliates.
   Copyright (c) 2020, 2022, MariaDB

   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 St, Fifth Floor, Boston, MA 02110-1335  USA */

#ifndef _SP_HEAD_H_
#define _SP_HEAD_H_

#ifdef USE_PRAGMA_INTERFACE
#pragma interface			/* gcc class implementation */
#endif

/*
  It is necessary to include set_var.h instead of item.h because there
  are dependencies on include order for set_var.h and item.h. This
  will be resolved later.
*/
#include "sql_class.h"                          // THD, set_var.h: THD
#include "set_var.h"                            // Item
#include "sp_pcontext.h"                        // sp_pcontext
#include <stddef.h>
#include "sp.h"

/**
  @defgroup Stored_Routines Stored Routines
  @ingroup Runtime_Environment
  @{
*/

uint
sp_get_flags_for_command(LEX *lex);

class sp_instr;
class sp_instr_opt_meta;
class sp_instr_jump_if_not;

/**
  Number of PSI_statement_info instruments
  for internal stored programs statements.
*/
#ifdef HAVE_PSI_INTERFACE
void init_sp_psi_keys(void);
#endif

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

/**
  Stored_program_creation_ctx -- base class for creation context of stored
  programs (stored routines, triggers, events).
*/

class Stored_program_creation_ctx :public Default_object_creation_ctx
{
public:
  CHARSET_INFO *get_db_cl()
  {
    return m_db_cl;
  }

public:
  virtual Stored_program_creation_ctx *clone(MEM_ROOT *mem_root) = 0;

protected:
  Stored_program_creation_ctx(THD *thd)
    : Default_object_creation_ctx(thd),
      m_db_cl(thd->variables.collation_database)
  { }

  Stored_program_creation_ctx(CHARSET_INFO *client_cs,
                              CHARSET_INFO *connection_cl,
                              CHARSET_INFO *db_cl)
    : Default_object_creation_ctx(client_cs, connection_cl),
      m_db_cl(db_cl)
  { }

protected:
  virtual void change_env(THD *thd) const
  {
    thd->variables.collation_database= m_db_cl;

    Default_object_creation_ctx::change_env(thd);
  }

protected:
  /**
    db_cl stores the value of the database collation. Both character set
    and collation attributes are used.

    Database collation is included into the context because it defines the
    default collation for stored-program variables.
  */
  CHARSET_INFO *m_db_cl;
};

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

class sp_name : public Sql_alloc,
                public Database_qualified_name
{
public:
  bool       m_explicit_name;                   /**< Prepend the db name? */

  sp_name(const LEX_CSTRING *db, const LEX_CSTRING *name,
          bool use_explicit_name)
    : Database_qualified_name(db, name), m_explicit_name(use_explicit_name)
  {
    if (lower_case_table_names && m_db.length)
      m_db.length= my_casedn_str(files_charset_info, (char*) m_db.str);
  }

  /** Create temporary sp_name object from MDL key. Store in qname_buff */
  sp_name(const MDL_key *key, char *qname_buff);

  ~sp_name() = default;
};


bool
check_routine_name(const LEX_CSTRING *ident);

class sp_head :private Query_arena,
               public Database_qualified_name,
               public Sql_alloc
{
  sp_head(const sp_head &)= delete;
  void operator=(sp_head &)= delete;

protected:
  MEM_ROOT main_mem_root;
#ifdef PROTECT_STATEMENT_MEMROOT
  /*
    The following data member is wholly for debugging purpose.
    It can be used for possible crash analysis to determine how many times
    the stored routine was executed before the mem_root marked read_only
    was requested for a memory chunk. Additionally, a value of this data
    member is output to the log with DBUG_PRINT.
  */
  ulong executed_counter;
#endif
public:
  /** Possible values of m_flags */
  enum {
    HAS_RETURN= 1,              // For FUNCTIONs only: is set if has RETURN
    MULTI_RESULTS= 8,           // Is set if a procedure with SELECT(s)
    CONTAINS_DYNAMIC_SQL= 16,   // Is set if a procedure with PREPARE/EXECUTE
    IS_INVOKED= 32,             // Is set if this sp_head is being used
    HAS_SET_AUTOCOMMIT_STMT= 64,// Is set if a procedure with 'set autocommit'
    /* Is set if a procedure with COMMIT (implicit or explicit) | ROLLBACK */
    HAS_COMMIT_OR_ROLLBACK= 128,
    LOG_SLOW_STATEMENTS= 256,   // Used by events
    LOG_GENERAL_LOG= 512,        // Used by events
    HAS_SQLCOM_RESET= 1024,
    HAS_SQLCOM_FLUSH= 2048,

    /**
      Marks routines that directly (i.e. not by calling other routines)
      change tables. Note that this flag is set automatically based on
      type of statements used in the stored routine and is different
      from routine characteristic provided by user in a form of CONTAINS
      SQL, READS SQL DATA, MODIFIES SQL DATA clauses. The latter are
      accepted by parser but pretty much ignored after that.
      We don't rely on them:
      a) for compatibility reasons.
      b) because in CONTAINS SQL case they don't provide enough
      information anyway.
     */
    MODIFIES_DATA= 4096,
    /*
      Marks routines that have column type references: DECLARE a t1.a%TYPE;
    */
    HAS_COLUMN_TYPE_REFS= 8192,
    /* Set if has FETCH GROUP NEXT ROW instr. Used to ensure that only
       functions with AGGREGATE keyword use the instr. */
    HAS_AGGREGATE_INSTR= 16384
  };

  sp_package *m_parent;
  const Sp_handler *m_handler;
  uint m_flags;                 // Boolean attributes of a stored routine

  /**
    Instrumentation interface for SP.
  */
  PSI_sp_share *m_sp_share;

  Column_definition m_return_field_def; /**< This is used for FUNCTIONs only. */

  const char *m_tmp_query;	///< Temporary pointer to sub query string
private:
  /*
    Private to guarantee that m_chistics.comment is properly set to:
    - a string which is alloced on this->mem_root
    - or (NULL,0)
    set_chistics() makes sure this.
  */
  Sp_chistics m_chistics;
  void set_chistics(const st_sp_chistics &chistics);
  inline void set_chistics_agg_type(enum enum_sp_aggregate_type type)
  {
    m_chistics.agg_type= type;
  }
public:
  sql_mode_t m_sql_mode;		///< For SHOW CREATE and execution
  bool       m_explicit_name;                   /**< Prepend the db name? */
  LEX_CSTRING m_qname;		///< db.name
  LEX_CSTRING m_params;
  LEX_CSTRING m_body;
  LEX_CSTRING m_body_utf8;
  LEX_CSTRING m_defstr;
  AUTHID      m_definer;

  const st_sp_chistics &chistics() const { return m_chistics; }
  const LEX_CSTRING &comment() const { return m_chistics.comment; }
  void set_suid(enum_sp_suid_behaviour suid) { m_chistics.suid= suid; }
  enum_sp_suid_behaviour suid() const { return m_chistics.suid; }
  bool detistic() const { return m_chistics.detistic; }
  enum_sp_data_access daccess() const { return m_chistics.daccess; }
  enum_sp_aggregate_type agg_type() const { return m_chistics.agg_type; }
  /**
    Is this routine being executed?
  */
  virtual bool is_invoked() const { return m_flags & IS_INVOKED; }

  /**
    Get the value of the SP cache version, as remembered
    when the routine was inserted into the cache.
  */
  ulong sp_cache_version() const;

  /** Set the value of the SP cache version.  */
  void set_sp_cache_version(ulong version_arg) const
  {
    m_sp_cache_version= version_arg;
  }

  sp_rcontext *rcontext_create(THD *thd, Field *retval, List<Item> *args);
  sp_rcontext *rcontext_create(THD *thd, Field *retval,
                               Item **args, uint arg_count);
  sp_rcontext *rcontext_create(THD *thd, Field *retval,
                               Row_definition_list *list,
                               bool switch_security_ctx);
  bool eq_routine_spec(const sp_head *) const;
private:
  /**
    Version of the stored routine cache at the moment when the
    routine was added to it. Is used only for functions and
    procedures, not used for triggers or events.  When sp_head is
    created, its version is 0. When it's added to the cache, the
    version is assigned the global value 'Cversion'.
    If later on Cversion is incremented, we know that the routine
    is obsolete and should not be used --
    sp_cache_flush_obsolete() will purge it.
  */
  mutable ulong m_sp_cache_version;
  Stored_program_creation_ctx *m_creation_ctx;
  /**
    Boolean combination of (1<<flag), where flag is a member of
    LEX::enum_binlog_stmt_unsafe.
  */
  uint32 unsafe_flags;

public:
  inline Stored_program_creation_ctx *get_creation_ctx()
  {
    return m_creation_ctx;
  }

  inline void set_creation_ctx(Stored_program_creation_ctx *creation_ctx)
  {
    m_creation_ctx= creation_ctx->clone(mem_root);
  }

  longlong m_created;
  longlong m_modified;
  /** Recursion level of the current SP instance. The levels are numbered from 0 */
  ulong m_recursion_level;
  /**
    A list of diferent recursion level instances for the same procedure.
    For every recursion level we have a sp_head instance. This instances
    connected in the list. The list ordered by increasing recursion level
    (m_recursion_level).
  */
  sp_head *m_next_cached_sp;
  /**
    Pointer to the first element of the above list
  */
  sp_head *m_first_instance;
  /**
    Pointer to the first free (non-INVOKED) routine in the list of
    cached instances for this SP. This pointer is set only for the first
    SP in the list of instences (see above m_first_cached_sp pointer).
    The pointer equal to 0 if we have no free instances.
    For non-first instance value of this pointer meanless (point to itself);
  */
  sp_head *m_first_free_instance;
  /**
    Pointer to the last element in the list of instances of the SP.
    For non-first instance value of this pointer meanless (point to itself);
  */
  sp_head *m_last_cached_sp;
  /**
    Set containing names of stored routines used by this routine.
    Note that unlike elements of similar set for statement elements of this
    set are not linked in one list. Because of this we are able save memory
    by using for this set same objects that are used in 'sroutines' sets
    for statements of which this stored routine consists.
  */
  HASH m_sroutines;
  // Pointers set during parsing
  const char *m_param_begin;
  const char *m_param_end;

private:
  /*
    A pointer to the body start inside the cpp buffer.
    Used only during parsing. Should be removed eventually.
    The affected functions/methods should be fixed to get the cpp body start
    as a parameter, rather than through this member.
  */
  const char *m_cpp_body_begin;

public:
  /*
    Security context for stored routine which should be run under
    definer privileges.
  */
  Security_context m_security_ctx;

  /**
    List of all items (Item_trigger_field objects) representing fields in
    old/new version of row in trigger. We use this list for checking whenever
    all such fields are valid at trigger creation time and for binding these
    fields to TABLE object at table open (although for latter pointer to table
    being opened is probably enough).
  */
  SQL_I_List<Item_trigger_field> m_trg_table_fields;

protected:
  sp_head(MEM_ROOT *mem_root, sp_package *parent, const Sp_handler *handler,
          enum_sp_aggregate_type agg_type);
  virtual ~sp_head();
public:
  static void destroy(sp_head *sp);
  static sp_head *create(sp_package *parent, const Sp_handler *handler,
                         enum_sp_aggregate_type agg_type);

  /// Initialize after we have reset mem_root
  void
  init(LEX *lex);

  /** Copy sp name from parser. */
  void
  init_sp_name(const sp_name *spname);

  /** Set the body-definition start position. */
  void
  set_body_start(THD *thd, const char *cpp_body_start);

  /** Set the statement-definition (body-definition) end position. */
  void
  set_stmt_end(THD *thd, const char *cpp_body_end);

  bool
  execute_trigger(THD *thd,
                  const LEX_CSTRING *db_name,
                  const LEX_CSTRING *table_name,
                  GRANT_INFO *grant_info);

  bool
  execute_function(THD *thd, Item **args, uint argcount, Field *return_fld,
                   sp_rcontext **nctx, Query_arena *call_arena);

  bool
  execute_procedure(THD *thd, List<Item> *args);

  static void
  show_create_routine_get_fields(THD *thd, const Sp_handler *sph,
                                 List<Item> *fields);

  bool
  show_create_routine(THD *thd, const Sp_handler *sph);

  MEM_ROOT *get_main_mem_root() { return &main_mem_root; }

  int
  add_instr(sp_instr *instr);

  bool
  add_instr_jump(THD *thd, sp_pcontext *spcont);

  bool
  add_instr_jump(THD *thd, sp_pcontext *spcont, uint dest);

  bool
  add_instr_jump_forward_with_backpatch(THD *thd, sp_pcontext *spcont,
                                        sp_label *lab);
  bool
  add_instr_jump_forward_with_backpatch(THD *thd, sp_pcontext *spcont)
  {
    return add_instr_jump_forward_with_backpatch(thd, spcont,
                                                 spcont->last_label());
  }

  bool
  add_instr_freturn(THD *thd, sp_pcontext *spcont, Item *item, LEX *lex);

  bool
  add_instr_preturn(THD *thd, sp_pcontext *spcont);

  Item *adjust_assignment_source(THD *thd, Item *val, Item *val2);
  /**
    @param thd                     - the current thd
    @param spcont                  - the current parse context
    @param spv                     - the SP variable
    @param val                     - the value to be assigned to the variable
    @param lex                     - the LEX that was used to create "val"
    @param responsible_to_free_lex - if the generated sp_instr_set should
                                     free "lex".
    @retval true                   - on error
    @retval false                  - on success
  */
  bool set_local_variable(THD *thd, sp_pcontext *spcont,
                          const Sp_rcontext_handler *rh,
                          sp_variable *spv, Item *val, LEX *lex,
                          bool responsible_to_free_lex);
  bool set_local_variable_row_field(THD *thd, sp_pcontext *spcont,
                                    const Sp_rcontext_handler *rh,
                                    sp_variable *spv, uint field_idx,
                                    Item *val, LEX *lex);
  bool set_local_variable_row_field_by_name(THD *thd, sp_pcontext *spcont,
                                            const Sp_rcontext_handler *rh,
                                            sp_variable *spv,
                                            const LEX_CSTRING *field_name,
                                            Item *val, LEX *lex);
  bool check_package_routine_end_name(const LEX_CSTRING &end_name) const;
  bool check_standalone_routine_end_name(const sp_name *end_name) const;
  bool check_group_aggregate_instructions_function() const;
  bool check_group_aggregate_instructions_forbid() const;
  bool check_group_aggregate_instructions_require() const;
private:
  /**
    Generate a code to set a single cursor parameter variable.
    @param thd          - current thd, for mem_root allocations.
    @param param_spcont - the context of the parameter block
    @param idx          - the index of the parameter
    @param prm          - the actual parameter (contains information about
                          the assignment source expression Item,
                          its free list, and its LEX)
  */
  bool add_set_cursor_param_variable(THD *thd,
                                     sp_pcontext *param_spcont, uint idx,
                                     sp_assignment_lex *prm)
  {
    DBUG_ASSERT(idx < param_spcont->context_var_count());
    sp_variable *spvar= param_spcont->get_context_variable(idx);
    /*
      add_instr() gets free_list from m_thd->free_list.
      Initialize it before the set_local_variable() call.
    */
    DBUG_ASSERT(m_thd->free_list == NULL);
    m_thd->free_list= prm->get_free_list();
    if (set_local_variable(thd, param_spcont,
                           &sp_rcontext_handler_local,
                           spvar, prm->get_item(), prm, true))
      return true;
    /*
      Safety:
      The item and its free_list are now fully owned by the sp_instr_set
      instance, created by set_local_variable(). The sp_instr_set instance
      is now responsible for freeing the item and the free_list.
      Reset the "item" and the "free_list" members of "prm",
      to avoid double pointers to the same objects from "prm" and
      from the sp_instr_set instance.
    */
    prm->set_item_and_free_list(NULL, NULL);
    return false;
  }

  /**
    Generate a code to set all cursor parameter variables.
    This method is called only when parameters exists,
    and the number of formal parameters matches the number of actual
    parameters. See also comments to add_open_cursor().
  */
  bool add_set_cursor_param_variables(THD *thd, sp_pcontext *param_spcont,
                                      List<sp_assignment_lex> *parameters)
  {
    DBUG_ASSERT(param_spcont->context_var_count() == parameters->elements);
    sp_assignment_lex *prm;
    List_iterator<sp_assignment_lex> li(*parameters);
    for (uint idx= 0; (prm= li++); idx++)
    {
      if (add_set_cursor_param_variable(thd, param_spcont, idx, prm))
        return true;
    }
    return false;
  }

  /**
    Generate a code to set all cursor parameter variables for a FOR LOOP, e.g.:
      FOR index IN cursor(1,2,3)
    @param
  */
  bool add_set_for_loop_cursor_param_variables(THD *thd,
                                               sp_pcontext *param_spcont,
                                               sp_assignment_lex *param_lex,
                                               Item_args *parameters);

  bool bind_input_param(THD *thd,
                        Item *arg_item,
                        uint arg_no,
                        sp_rcontext *nctx,
                        bool is_function);

  bool bind_output_param(THD *thd,
                         Item *arg_item,
                         uint arg_no,
                         sp_rcontext *octx,
                         sp_rcontext *nctx);

public:
  /**
    Generate a code for an "OPEN cursor" statement.
    @param thd          - current thd, for mem_root allocations
    @param spcont       - the context of the cursor
    @param offset       - the offset of the cursor
    @param param_spcont - the context of the cursor parameter block
    @param parameters   - the list of the OPEN actual parameters

    The caller must make sure that the number of local variables
    in "param_spcont" (formal parameters) matches the number of list elements
    in "parameters" (actual parameters).
    NULL in either of them means 0 parameters.
  */
  bool add_open_cursor(THD *thd, sp_pcontext *spcont,
                       uint offset,
                       sp_pcontext *param_spcont,
                       List<sp_assignment_lex> *parameters);

  /**
    Generate an initiation code for a CURSOR FOR LOOP, e.g.:
      FOR index IN cursor         -- cursor without parameters
      FOR index IN cursor(1,2,3)  -- cursor with parameters

    The code generated by this method does the following during SP run-time:
    - Sets all cursor parameter vartiables from "parameters"
    - Initializes the index ROW-type variable from the cursor
      (the structure is copied from the cursor to the index variable)
    - The cursor gets opened
    - The first records is fetched from the cursor to the variable "index".

    @param thd        - the current thread (for mem_root and error reporting)
    @param spcont     - the current parse context
    @param index      - the loop "index" ROW-type variable
    @param pcursor    - the cursor
    @param coffset    - the cursor offset
    @param param_lex  - the LEX that owns Items in "parameters"
    @param parameters - the cursor parameters Item array
    @retval true      - on error (EOM)
    @retval false     - on success
  */
  bool add_for_loop_open_cursor(THD *thd, sp_pcontext *spcont,
                                sp_variable *index,
                                const sp_pcursor *pcursor, uint coffset,
                                sp_assignment_lex *param_lex,
                                Item_args *parameters);
  /**
    Returns true if any substatement in the routine directly
    (not through another routine) modifies data/changes table.

    @sa Comment for MODIFIES_DATA flag.
  */
  bool modifies_data() const
  { return m_flags & MODIFIES_DATA; }

  inline uint instructions()
  { return (uint)m_instr.elements; }

  inline sp_instr *
  last_instruction()
  {
    sp_instr *i;

    get_dynamic(&m_instr, (uchar*)&i, m_instr.elements-1);
    return i;
  }

  bool replace_instr_to_nop(THD *thd, uint ip);

  /*
    Resets lex in 'thd' and keeps a copy of the old one.

    @todo Conflicting comment in sp_head.cc
  */
  bool
  reset_lex(THD *thd);

  bool
  reset_lex(THD *thd, sp_lex_local *sublex);

  /**
    Merge two LEX instances.
    @param oldlex - the upper level LEX we're going to restore to.
    @param sublex - the local lex that have just parsed some substatement.
    @returns      - false on success, true on error (e.g. failed to
                    merge the routine list or the table list).
    This method is shared by:
    - restore_lex(), when the old LEX is popped by sp_head::m_lex.pop()
    - THD::restore_from_local_lex_to_old_lex(), when the old LEX
      is stored in the caller's local variable.
  */
  bool
  merge_lex(THD *thd, LEX *oldlex, LEX *sublex);

  /**
    Restores lex in 'thd' from our copy, but keeps some status from the
    one in 'thd', like ptr, tables, fields, etc.

    @todo Conflicting comment in sp_head.cc
  */
  bool
  restore_lex(THD *thd)
  {
    DBUG_ENTER("sp_head::restore_lex");
    /*
      There is no a need to free the current thd->lex here.
      - In the majority of the cases restore_lex() is called
        on success and thd->lex does not need to be deleted.
      - In cases when restore_lex() is called on error,
        e.g. from sp_create_assignment_instr(), thd->lex is
        already linked to some sp_instr_xxx (using sp_lex_keeper).

      Note, we don't get to here in case of a syntax error
      when the current thd->lex is not yet completely
      initialized and linked. It gets automatically deleted
      by the Bison %destructor in sql_yacc.yy.
    */
    LEX *oldlex= (LEX *) m_lex.pop();
    if (!oldlex)
      DBUG_RETURN(false); // Nothing to restore
    // This restores thd->lex and thd->stmt_lex
    DBUG_RETURN(thd->restore_from_local_lex_to_old_lex(oldlex));
  }

  /**
    Iterate through the LEX stack from the top (the newest) to the bottom
    (the oldest) and find the one that contains a non-zero spname.
    @returns - the address of spname, or NULL of no spname found.
  */
  const sp_name *find_spname_recursive()
  {
    uint count= m_lex.elements;
    for (uint i= 0; i < count; i++)
    {
      const LEX *tmp= m_lex.elem(count - i - 1);
      if (tmp->spname)
        return tmp->spname;
    }
    return NULL;
  }

  /// Put the instruction on the backpatch list, associated with the label.
  int
  push_backpatch(THD *thd, sp_instr *, sp_label *);
  int
  push_backpatch_goto(THD *thd, sp_pcontext *ctx, sp_label *lab);

  /// Update all instruction with this label in the backpatch list to
  /// the current position.
  void
  backpatch(sp_label *);
  void
  backpatch_goto(THD *thd, sp_label *, sp_label *);

  /// Check for unresolved goto label
  bool
  check_unresolved_goto();

  /// Start a new cont. backpatch level. If 'i' is NULL, the level is just incr.
  int
  new_cont_backpatch(sp_instr_opt_meta *i);

  /// Add an instruction to the current level
  int
  add_cont_backpatch(sp_instr_opt_meta *i);

  /// Backpatch (and pop) the current level to the current position.
  void
  do_cont_backpatch();

  /// Add cpush instructions for all cursors declared in the current frame
  bool sp_add_instr_cpush_for_cursors(THD *thd, sp_pcontext *pcontext);

  const LEX_CSTRING *name() const
  { return &m_name; }

  char *create_string(THD *thd, ulong *lenp);

  Field *create_result_field(uint field_max_length, const LEX_CSTRING *field_name,
                             TABLE *table) const;


  /**
    Check and prepare an instance of Column_definition for field creation
    (fill all necessary attributes), for variables, parameters and
    function return values.

    @param[in]  thd          Thread handle
    @param[in]  lex          Yacc parsing context
    @param[out] field_def    An instance of create_field to be filled

    @retval false on success
    @retval true  on error
  */
  bool fill_field_definition(THD *thd, Column_definition *field_def)
  {
    const Type_handler *h= field_def->type_handler();
    return h->Column_definition_fix_attributes(field_def) ||
           field_def->sp_prepare_create_field(thd, mem_root);
  }
  bool row_fill_field_definitions(THD *thd, Row_definition_list *row)
  {
    /*
      Prepare all row fields. This will (among other things)
      - convert VARCHAR lengths from character length to octet length
      - calculate interval lengths for SET and ENUM
    */
    List_iterator<Spvar_definition> it(*row);
    for (Spvar_definition *def= it++; def; def= it++)
    {
      if (fill_spvar_definition(thd, def))
        return true;
    }
    return false;
  }
  /**
    Check and prepare a Column_definition for a variable or a parameter.
  */
  bool fill_spvar_definition(THD *thd, Column_definition *def)
  {
    if (fill_field_definition(thd, def))
      return true;
    def->pack_flag|= FIELDFLAG_MAYBE_NULL;
    return false;
  }
  bool fill_spvar_definition(THD *thd, Column_definition *def,
                             LEX_CSTRING *name)
  {
    def->field_name= *name;
    return fill_spvar_definition(thd, def);
  }

private:
  /**
    Set a column type reference for a parameter definition
  */
  void fill_spvar_using_type_reference(sp_variable *spvar,
                                       Qualified_column_ident *ref)
  {
    spvar->field_def.set_column_type_ref(ref);
    spvar->field_def.field_name= spvar->name;
    m_flags|= sp_head::HAS_COLUMN_TYPE_REFS;
  }

  void fill_spvar_using_table_rowtype_reference(THD *thd,
                                                sp_variable *spvar,
                                                Table_ident *ref)
  {
    spvar->field_def.set_table_rowtype_ref(ref);
    spvar->field_def.field_name= spvar->name;
    fill_spvar_definition(thd, &spvar->field_def);
    m_flags|= sp_head::HAS_COLUMN_TYPE_REFS;
  }

public:
  bool spvar_fill_row(THD *thd, sp_variable *spvar, Row_definition_list *def);
  bool spvar_fill_type_reference(THD *thd, sp_variable *spvar,
                                 const LEX_CSTRING &table,
                                 const LEX_CSTRING &column);
  bool spvar_fill_type_reference(THD *thd, sp_variable *spvar,
                                 const LEX_CSTRING &db,
                                 const LEX_CSTRING &table,
                                 const LEX_CSTRING &column);
  bool spvar_fill_table_rowtype_reference(THD *thd, sp_variable *spvar,
                                          const LEX_CSTRING &table);
  bool spvar_fill_table_rowtype_reference(THD *thd, sp_variable *spvar,
                                          const LEX_CSTRING &db,
                                          const LEX_CSTRING &table);

  void set_c_chistics(const st_sp_chistics &chistics);
  void set_info(longlong created, longlong modified,
		const st_sp_chistics &chistics, sql_mode_t sql_mode);

  void set_definer(const char *definer, size_t definerlen)
  {
    AUTHID tmp;
    tmp.parse(definer, definerlen);
    m_definer.copy(mem_root, &tmp.user, &tmp.host);
  }
  void set_definer(const LEX_CSTRING *user_name, const LEX_CSTRING *host_name)
  {
    m_definer.copy(mem_root, user_name, host_name);
  }

  void reset_thd_mem_root(THD *thd);

  void restore_thd_mem_root(THD *thd);

  /**
    Optimize the code.
  */
  void optimize();

  /**
    Helper used during flow analysis during code optimization.
    See the implementation of <code>opt_mark()</code>.
    @param ip the instruction to add to the leads list
    @param leads the list of remaining paths to explore in the graph that
    represents the code, during flow analysis.
  */
  void add_mark_lead(uint ip, List<sp_instr> *leads);

  inline sp_instr *
  get_instr(uint i)
  {
    sp_instr *ip;

    if (i < m_instr.elements)
      get_dynamic(&m_instr, (uchar*)&ip, i);
    else
      ip= NULL;
    return ip;
  }

#ifdef PROTECT_STATEMENT_MEMROOT
  int has_all_instrs_executed();
  void reset_instrs_executed_counter();
#endif

  /* Add tables used by routine to the table list. */
  bool add_used_tables_to_table_list(THD *thd,
                                     TABLE_LIST ***query_tables_last_ptr,
                                     TABLE_LIST *belong_to_view);

  /**
    Check if this stored routine contains statements disallowed
    in a stored function or trigger, and set an appropriate error message
    if this is the case.
  */
  bool is_not_allowed_in_function(const char *where)
  {
    if (m_flags & CONTAINS_DYNAMIC_SQL)
      my_error(ER_STMT_NOT_ALLOWED_IN_SF_OR_TRG, MYF(0), "Dynamic SQL");
    else if (m_flags & MULTI_RESULTS)
      my_error(ER_SP_NO_RETSET, MYF(0), where);
    else if (m_flags & HAS_SET_AUTOCOMMIT_STMT)
      my_error(ER_SP_CANT_SET_AUTOCOMMIT, MYF(0));
    else if (m_flags & HAS_COMMIT_OR_ROLLBACK)
      my_error(ER_COMMIT_NOT_ALLOWED_IN_SF_OR_TRG, MYF(0));
    else if (m_flags & HAS_SQLCOM_RESET)
      my_error(ER_STMT_NOT_ALLOWED_IN_SF_OR_TRG, MYF(0), "RESET");
    else if (m_flags & HAS_SQLCOM_FLUSH)
      my_error(ER_STMT_NOT_ALLOWED_IN_SF_OR_TRG, MYF(0), "FLUSH");

    return MY_TEST(m_flags &
                  (CONTAINS_DYNAMIC_SQL | MULTI_RESULTS |
                   HAS_SET_AUTOCOMMIT_STMT | HAS_COMMIT_OR_ROLLBACK |
                   HAS_SQLCOM_RESET | HAS_SQLCOM_FLUSH));
  }

#ifndef DBUG_OFF
  int show_routine_code(THD *thd);
#endif

  /*
    This method is intended for attributes of a routine which need
    to propagate upwards to the Query_tables_list of the caller (when
    a property of a sp_head needs to "taint" the calling statement).
  */
  void propagate_attributes(Query_tables_list *prelocking_ctx)
  {
    DBUG_ENTER("sp_head::propagate_attributes");
    /*
      If this routine needs row-based binary logging, the entire top statement
      too (we cannot switch from statement-based to row-based only for this
      routine, as in statement-based the top-statement may be binlogged and
      the substatements not).
    */
    DBUG_PRINT("info", ("lex->get_stmt_unsafe_flags(): 0x%x",
                        prelocking_ctx->get_stmt_unsafe_flags()));
    DBUG_PRINT("info", ("sp_head(%p=%s)->unsafe_flags: 0x%x",
                        this, name()->str, unsafe_flags));
    prelocking_ctx->set_stmt_unsafe_flags(unsafe_flags);
    DBUG_VOID_RETURN;
  }

  sp_pcontext *get_parse_context() { return m_pcont; }

  /*
    Check EXECUTE access:
    - in case of a standalone rotuine, for the routine itself
    - in case of a package routine, for the owner package body
  */
  bool check_execute_access(THD *thd) const;

  virtual sp_package *get_package()
  {
    return NULL;
  }

  virtual void init_psi_share();

protected:

  MEM_ROOT *m_thd_root;		///< Temp. store for thd's mem_root
  THD *m_thd;			///< Set if we have reset mem_root

  sp_pcontext *m_pcont;		///< Parse context
  List<LEX> m_lex;		///< Temp. store for the other lex
  DYNAMIC_ARRAY m_instr;	///< The "instructions"

  enum backpatch_instr_type { GOTO, CPOP, HPOP };
  typedef struct
  {
    sp_label *lab;
    sp_instr *instr;
    backpatch_instr_type instr_type;
  } bp_t;
  List<bp_t> m_backpatch;	///< Instructions needing backpatching
  List<bp_t> m_backpatch_goto; // Instructions needing backpatching (for goto)

  /**
    We need a special list for backpatching of instructions with a continue
    destination (in the case of a continue handler catching an error in
    the test), since it would otherwise interfere with the normal backpatch
    mechanism - e.g. jump_if_not instructions have two different destinations
    which are to be patched differently.
    Since these occur in a more restricted way (always the same "level" in
    the code), we don't need the label.
  */
  List<sp_instr_opt_meta> m_cont_backpatch;
  uint m_cont_level;            // The current cont. backpatch level

  /**
    Multi-set representing optimized list of tables to be locked by this
    routine. Does not include tables which are used by invoked routines.

    @note
    For prelocking-free SPs this multiset is constructed too.
    We do so because the same instance of sp_head may be called both
    in prelocked mode and in non-prelocked mode.
  */
  HASH m_sptabs;

  bool
  execute(THD *thd, bool merge_da_on_success);

  /**
    Perform a forward flow analysis in the generated code.
    Mark reachable instructions, for the optimizer.
  */
  void opt_mark();

  /**
    Merge the list of tables used by query into the multi-set of tables used
    by routine.
  */
  bool merge_table_list(THD *thd, TABLE_LIST *table, LEX *lex_for_tmp_check);

  /// Put the instruction on the a backpatch list, associated with the label.
  int
  push_backpatch(THD *thd, sp_instr *, sp_label *, List<bp_t> *list,
                 backpatch_instr_type itype);

}; // class sp_head : public Sql_alloc


class sp_package: public sp_head
{
  bool validate_public_routines(THD *thd, sp_package *spec);
  bool validate_private_routines(THD *thd);
public:
  class LexList: public List<LEX>
  {
  public:
    LexList() { elements= 0; }
    // Find a package routine by a non qualified name
    LEX *find(const LEX_CSTRING &name, enum_sp_type type);
    // Find a package routine by a package-qualified name, e.g. 'pkg.proc'
    LEX *find_qualified(const LEX_CSTRING &name, enum_sp_type type);
    // Check if a routine with the given qualified name already exists
    bool check_dup_qualified(const LEX_CSTRING &name, const Sp_handler *sph)
    {
      if (!find_qualified(name, sph->type()))
        return false;
      my_error(ER_SP_ALREADY_EXISTS, MYF(0), sph->type_str(), name.str);
      return true;
    }
    bool check_dup_qualified(const sp_head *sp)
    {
      return check_dup_qualified(sp->m_name, sp->m_handler);
    }
    void cleanup();
  };
  /*
    The LEX for a new package subroutine is initially assigned to
    m_current_routine. After scanning parameters, return type and chistics,
    the parser detects if we have a declaration or a definition, e.g.:
         PROCEDURE p1(a INT);
      vs
         PROCEDURE p1(a INT) AS BEGIN NULL; END;
    (i.e. either semicolon or the "AS" keyword)
    m_current_routine is then added either to m_routine_implementations,
    or m_routine_declarations, and then m_current_routine is set to NULL.
  */
  LEX *m_current_routine;
  LexList m_routine_implementations;
  LexList m_routine_declarations;

  LEX *m_top_level_lex;
  sp_rcontext *m_rcontext;
  uint m_invoked_subroutine_count;
  bool m_is_instantiated;
  bool m_is_cloning_routine;

private:
  sp_package(MEM_ROOT *mem_root,
             LEX *top_level_lex,
             const sp_name *name,
             const Sp_handler *sph);
  ~sp_package();
public:
  static sp_package *create(LEX *top_level_lex, const sp_name *name,
                            const Sp_handler *sph);

  bool add_routine_declaration(LEX *lex)
  {
    return m_routine_declarations.check_dup_qualified(lex->sphead) ||
           m_routine_declarations.push_back(lex, &main_mem_root);
  }
  bool add_routine_implementation(LEX *lex)
  {
    return m_routine_implementations.check_dup_qualified(lex->sphead) ||
           m_routine_implementations.push_back(lex, &main_mem_root);
  }
  sp_package *get_package() { return this; }
  void init_psi_share();
  bool is_invoked() const
  {
    /*
      Cannot flush a package out of the SP cache when:
      - its initialization block is running
      - one of its subroutine is running
    */
    return sp_head::is_invoked() || m_invoked_subroutine_count > 0;
  }
  sp_variable *find_package_variable(const LEX_CSTRING *name) const
  {
    /*
      sp_head::m_pcont is a special level for routine parameters.
      Variables declared inside CREATE PACKAGE BODY reside in m_children.at(0).
    */
    sp_pcontext *ctx= m_pcont->child_context(0);
    return ctx ? ctx->find_variable(name, true) : NULL;
  }
  bool validate_after_parser(THD *thd);
  bool instantiate_if_needed(THD *thd);
};


class sp_lex_cursor: public sp_lex_local, public Query_arena
{
public:
  sp_lex_cursor(THD *thd, const LEX *oldlex, MEM_ROOT *mem_root_arg)
   :sp_lex_local(thd, oldlex),
    Query_arena(mem_root_arg, STMT_INITIALIZED_FOR_SP)
  { }
  sp_lex_cursor(THD *thd, const LEX *oldlex)
   :sp_lex_local(thd, oldlex),
    Query_arena(thd->lex->sphead->get_main_mem_root(), STMT_INITIALIZED_FOR_SP)
  { }
  ~sp_lex_cursor() { free_items(); }
  virtual bool cleanup_stmt(bool /*restore_set_statement_vars*/) override
  { return false; }
  Query_arena *query_arena() override { return this; }
  bool validate()
  {
    DBUG_ASSERT(sql_command == SQLCOM_SELECT);
    if (result)
    {
      my_error(ER_SP_BAD_CURSOR_SELECT, MYF(0));
      return true;
    }
    return false;
  }
  bool stmt_finalize(THD *thd)
  {
    if (validate())
      return true;
    sp_lex_in_use= true;
    free_list= thd->free_list;
    thd->free_list= NULL;
    return false;
  }
};


//
// "Instructions"...
//

class sp_instr :public Query_arena, public Sql_alloc
{
  sp_instr(const sp_instr &);	/**< Prevent use of these */
  void operator=(sp_instr &);

public:

  uint marked;
  uint m_ip;			///< My index
  sp_pcontext *m_ctx;		///< My parse context
  uint m_lineno;

  /// Should give each a name or type code for debugging purposes?
  sp_instr(uint ip, sp_pcontext *ctx)
    :Query_arena(0, STMT_INITIALIZED_FOR_SP), marked(0), m_ip(ip), m_ctx(ctx)
#ifdef PROTECT_STATEMENT_MEMROOT
  , m_has_been_run(false)
#endif
  {}

  virtual ~sp_instr()
  { free_items(); }


  /**
    Execute this instruction

   
    @param thd         Thread handle
    @param[out] nextp  index of the next instruction to execute. (For most
                       instructions this will be the instruction following this
                       one). Note that this parameter is undefined in case of
                       errors, use get_cont_dest() to find the continuation
                       instruction for CONTINUE error handlers.
   
    @retval 0      on success, 
    @retval other  if some error occurred
  */

  virtual int execute(THD *thd, uint *nextp) = 0;

  /**
    Execute <code>open_and_lock_tables()</code> for this statement.
    Open and lock the tables used by this statement, as a pre-requisite
    to execute the core logic of this instruction with
    <code>exec_core()</code>.
    @param thd the current thread
    @param tables the list of tables to open and lock
    @return zero on success, non zero on failure.
  */
  int exec_open_and_lock_tables(THD *thd, TABLE_LIST *tables);

  /**
    Get the continuation destination of this instruction.
    @return the continuation destination
  */
  virtual uint get_cont_dest() const;

  /*
    Execute core function of instruction after all preparations (e.g.
    setting of proper LEX, saving part of the thread context have been
    done).

    Should be implemented for instructions using expressions or whole
    statements (thus having to have own LEX). Used in concert with
    sp_lex_keeper class and its descendants (there are none currently).
  */
  virtual int exec_core(THD *thd, uint *nextp);

  virtual void print(String *str) = 0;

  virtual void backpatch(uint dest, sp_pcontext *dst_ctx)
  {}

  /**
    Mark this instruction as reachable during optimization and return the
    index to the next instruction. Jump instruction will add their
    destination to the leads list.
  */
  virtual uint opt_mark(sp_head *sp, List<sp_instr> *leads)
  {
    marked= 1;
    return m_ip+1;
  }

  /**
    Short-cut jumps to jumps during optimization. This is used by the
    jump instructions' opt_mark() methods. 'start' is the starting point,
    used to prevent the mark sweep from looping for ever. Return the
    end destination.
  */
  virtual uint opt_shortcut_jump(sp_head *sp, sp_instr *start)
  {
    return m_ip;
  }

  /**
    Inform the instruction that it has been moved during optimization.
    Most instructions will simply update its index, but jump instructions
    must also take care of their destination pointers. Forward jumps get
    pushed to the backpatch list 'ibp'.
  */
  virtual void opt_move(uint dst, List<sp_instr> *ibp)
  {
    m_ip= dst;
  }
  virtual PSI_statement_info* get_psi_info() = 0;

#ifdef PROTECT_STATEMENT_MEMROOT
  bool has_been_run() const
  {
    return m_has_been_run;
  }

  void mark_as_run()
  {
    m_has_been_run= true;
  }

  void mark_as_not_run()
  {
    m_has_been_run= false;
  }

private:
  bool m_has_been_run;
#endif
}; // class sp_instr : public Sql_alloc


/**
  Auxilary class to which instructions delegate responsibility
  for handling LEX and preparations before executing statement
  or calculating complex expression.

  Exist mainly to avoid having double hierarchy between instruction
  classes.

  @todo
    Add ability to not store LEX and do any preparations if
    expression used is simple.
*/

class sp_lex_keeper
{
  /** Prevent use of these */
  sp_lex_keeper(const sp_lex_keeper &);
  void operator=(sp_lex_keeper &);
public:

  sp_lex_keeper(LEX *lex, bool lex_resp)
    : m_lex(lex), m_lex_resp(lex_resp), 
      lex_query_tables_own_last(NULL)
  {
    lex->sp_lex_in_use= TRUE;
  }
  virtual ~sp_lex_keeper()
  {
    if (m_lex_resp)
    {
      /* Prevent endless recursion. */
      m_lex->sphead= NULL;
      lex_end(m_lex);
      delete m_lex;
    }
  }

  /**
    Prepare execution of instruction using LEX, if requested check whenever
    we have read access to tables used and open/lock them, call instruction's
    exec_core() method, perform cleanup afterwards.
   
    @todo Conflicting comment in sp_head.cc
  */
  int reset_lex_and_exec_core(THD *thd, uint *nextp, bool open_tables,
                              sp_instr* instr);

  int cursor_reset_lex_and_exec_core(THD *thd, uint *nextp, bool open_tables,
                                     sp_instr *instr);

  inline uint sql_command() const
  {
    return (uint)m_lex->sql_command;
  }

  void disable_query_cache()
  {
    m_lex->safe_to_cache_query= 0;
  }

private:

  LEX *m_lex;
  /**
    Indicates whenever this sp_lex_keeper instance responsible
    for LEX deletion.
  */
  bool m_lex_resp;

  /*
    Support for being able to execute this statement in two modes:
    a) inside prelocked mode set by the calling procedure or its ancestor.
    b) outside of prelocked mode, when this statement enters/leaves
       prelocked mode itself.
  */
  
  /**
    List of additional tables this statement needs to lock when it
    enters/leaves prelocked mode on its own.
  */
  TABLE_LIST *prelocking_tables;

  /**
    The value m_lex->query_tables_own_last should be set to this when the
    statement enters/leaves prelocked mode on its own.
  */
  TABLE_LIST **lex_query_tables_own_last;
};


/**
  Call out to some prepared SQL statement.
*/
class sp_instr_stmt : public sp_instr
{
  sp_instr_stmt(const sp_instr_stmt &);	/**< Prevent use of these */
  void operator=(sp_instr_stmt &);

public:

  LEX_STRING m_query;		///< For thd->query

  sp_instr_stmt(uint ip, sp_pcontext *ctx, LEX *lex)
    : sp_instr(ip, ctx), m_lex_keeper(lex, TRUE)
  {
    m_query.str= 0;
    m_query.length= 0;
  }

  virtual ~sp_instr_stmt() = default;

  virtual int execute(THD *thd, uint *nextp);

  virtual int exec_core(THD *thd, uint *nextp);

  virtual void print(String *str);

private:

  sp_lex_keeper m_lex_keeper;

public:
  virtual PSI_statement_info* get_psi_info() { return & psi_info; }
  static PSI_statement_info psi_info;

}; // class sp_instr_stmt : public sp_instr


class sp_instr_set : public sp_instr
{
  sp_instr_set(const sp_instr_set &);	/**< Prevent use of these */
  void operator=(sp_instr_set &);

public:

  sp_instr_set(uint ip, sp_pcontext *ctx,
               const Sp_rcontext_handler *rh,
	       uint offset, Item *val,
               LEX *lex, bool lex_resp)
    : sp_instr(ip, ctx),
      m_rcontext_handler(rh), m_offset(offset), m_value(val),
      m_lex_keeper(lex, lex_resp)
  {}

  virtual ~sp_instr_set() = default;

  virtual int execute(THD *thd, uint *nextp);

  virtual int exec_core(THD *thd, uint *nextp);

  virtual void print(String *str);

protected:
  sp_rcontext *get_rcontext(THD *thd) const;
  const Sp_rcontext_handler *m_rcontext_handler;
  uint m_offset;		///< Frame offset
  Item *m_value;
  sp_lex_keeper m_lex_keeper;

public:
  virtual PSI_statement_info* get_psi_info() { return & psi_info; }
  static PSI_statement_info psi_info;
}; // class sp_instr_set : public sp_instr


/*
  This class handles assignments of a ROW fields:
    DECLARE rec ROW (a INT,b INT);
    SET rec.a= 10;
*/
class sp_instr_set_row_field : public sp_instr_set
{
  sp_instr_set_row_field(const sp_instr_set_row_field &); // Prevent use of this
  void operator=(sp_instr_set_row_field &);
  uint m_field_offset;

public:

  sp_instr_set_row_field(uint ip, sp_pcontext *ctx,
                         const Sp_rcontext_handler *rh,
                         uint offset, uint field_offset,
                         Item *val,
                         LEX *lex, bool lex_resp)
    : sp_instr_set(ip, ctx, rh, offset, val, lex, lex_resp),
      m_field_offset(field_offset)
  {}

  virtual ~sp_instr_set_row_field() = default;

  virtual int exec_core(THD *thd, uint *nextp);

  virtual void print(String *str);
}; // class sp_instr_set_field : public sp_instr_set


/**
  This class handles assignment instructions like this:
  DECLARE
    CURSOR cur IS SELECT * FROM t1;
    rec cur%ROWTYPE;
  BEGIN
    rec.column1:= 10; -- This instruction
  END;

  The idea is that during sp_rcontext::create() we do not know the extact
  structure of "rec". It gets resolved at run time, during the corresponding
  sp_instr_cursor_copy_struct::exec_core().

  So sp_instr_set_row_field_by_name searches for ROW fields by name,
  while sp_instr_set_row_field (see above) searches for ROW fields by index.
*/
class sp_instr_set_row_field_by_name : public sp_instr_set
{
  // Prevent use of this
  sp_instr_set_row_field_by_name(const sp_instr_set_row_field &);
  void operator=(sp_instr_set_row_field_by_name &);
  const LEX_CSTRING m_field_name;

public:

  sp_instr_set_row_field_by_name(uint ip, sp_pcontext *ctx,
                                 const Sp_rcontext_handler *rh,
                                 uint offset, const LEX_CSTRING &field_name,
                                 Item *val,
                                 LEX *lex, bool lex_resp)
    : sp_instr_set(ip, ctx, rh, offset, val, lex, lex_resp),
      m_field_name(field_name)
  {}

  virtual ~sp_instr_set_row_field_by_name() = default;

  virtual int exec_core(THD *thd, uint *nextp);

  virtual void print(String *str);
}; // class sp_instr_set_field_by_name : public sp_instr_set


/**
  Set NEW/OLD row field value instruction. Used in triggers.
*/
class sp_instr_set_trigger_field : public sp_instr
{
  sp_instr_set_trigger_field(const sp_instr_set_trigger_field &);
  void operator=(sp_instr_set_trigger_field &);

public:

  sp_instr_set_trigger_field(uint ip, sp_pcontext *ctx,
                             Item_trigger_field *trg_fld,
                             Item *val, LEX *lex)
    : sp_instr(ip, ctx),
      trigger_field(trg_fld),
      value(val), m_lex_keeper(lex, TRUE)
  {}

  virtual ~sp_instr_set_trigger_field() = default;

  virtual int execute(THD *thd, uint *nextp);

  virtual int exec_core(THD *thd, uint *nextp);

  virtual void print(String *str);

private:
  Item_trigger_field *trigger_field;
  Item *value;
  sp_lex_keeper m_lex_keeper;

public:
  virtual PSI_statement_info* get_psi_info() { return & psi_info; }
  static PSI_statement_info psi_info;
}; // class sp_instr_trigger_field : public sp_instr


/**
  An abstract class for all instructions with destinations that
  needs to be updated by the optimizer.

  Even if not all subclasses will use both the normal destination and
  the continuation destination, we put them both here for simplicity.
*/
class sp_instr_opt_meta : public sp_instr
{
public:

  uint m_dest;			///< Where we will go
  uint m_cont_dest;             ///< Where continue handlers will go

  sp_instr_opt_meta(uint ip, sp_pcontext *ctx)
    : sp_instr(ip, ctx),
      m_dest(0), m_cont_dest(0), m_optdest(0), m_cont_optdest(0)
  {}

  sp_instr_opt_meta(uint ip, sp_pcontext *ctx, uint dest)
    : sp_instr(ip, ctx),
      m_dest(dest), m_cont_dest(0), m_optdest(0), m_cont_optdest(0)
  {}

  virtual ~sp_instr_opt_meta() = default;

  virtual void set_destination(uint old_dest, uint new_dest)
    = 0;

  virtual uint get_cont_dest() const;

protected:

  sp_instr *m_optdest;		///< Used during optimization
  sp_instr *m_cont_optdest;     ///< Used during optimization

}; // class sp_instr_opt_meta : public sp_instr

class sp_instr_jump : public sp_instr_opt_meta
{
  sp_instr_jump(const sp_instr_jump &);	/**< Prevent use of these */
  void operator=(sp_instr_jump &);

public:

  sp_instr_jump(uint ip, sp_pcontext *ctx)
    : sp_instr_opt_meta(ip, ctx)
  {}

  sp_instr_jump(uint ip, sp_pcontext *ctx, uint dest)
    : sp_instr_opt_meta(ip, ctx, dest)
  {}

  virtual ~sp_instr_jump() = default;

  virtual int execute(THD *thd, uint *nextp);

  virtual void print(String *str);

  virtual uint opt_mark(sp_head *sp, List<sp_instr> *leads);

  virtual uint opt_shortcut_jump(sp_head *sp, sp_instr *start);

  virtual void opt_move(uint dst, List<sp_instr> *ibp);

  virtual void backpatch(uint dest, sp_pcontext *dst_ctx)
  {
    /* Calling backpatch twice is a logic flaw in jump resolution. */
    DBUG_ASSERT(m_dest == 0);
    m_dest= dest;
  }

  /**
    Update the destination; used by the optimizer.
  */
  virtual void set_destination(uint old_dest, uint new_dest)
  {
    if (m_dest == old_dest)
      m_dest= new_dest;
  }

public:
  virtual PSI_statement_info* get_psi_info() { return & psi_info; }
  static PSI_statement_info psi_info;
}; // class sp_instr_jump : public sp_instr_opt_meta


class sp_instr_jump_if_not : public sp_instr_jump
{
  sp_instr_jump_if_not(const sp_instr_jump_if_not &); /**< Prevent use of these */
  void operator=(sp_instr_jump_if_not &);

public:

  sp_instr_jump_if_not(uint ip, sp_pcontext *ctx, Item *i, LEX *lex)
    : sp_instr_jump(ip, ctx), m_expr(i),
      m_lex_keeper(lex, TRUE)
  {}

  sp_instr_jump_if_not(uint ip, sp_pcontext *ctx, Item *i, uint dest, LEX *lex)
    : sp_instr_jump(ip, ctx, dest), m_expr(i),
      m_lex_keeper(lex, TRUE)
  {}

  virtual ~sp_instr_jump_if_not() = default;

  virtual int execute(THD *thd, uint *nextp);

  virtual int exec_core(THD *thd, uint *nextp);

  virtual void print(String *str);

  virtual uint opt_mark(sp_head *sp, List<sp_instr> *leads);

  /** Override sp_instr_jump's shortcut; we stop here */
  virtual uint opt_shortcut_jump(sp_head *sp, sp_instr *start)
  {
    return m_ip;
  }

  virtual void opt_move(uint dst, List<sp_instr> *ibp);

  virtual void set_destination(uint old_dest, uint new_dest)
  {
    sp_instr_jump::set_destination(old_dest, new_dest);
    if (m_cont_dest == old_dest)
      m_cont_dest= new_dest;
  }

private:

  Item *m_expr;			///< The condition
  sp_lex_keeper m_lex_keeper;

public:
  virtual PSI_statement_info* get_psi_info() { return & psi_info; }
  static PSI_statement_info psi_info;
}; // class sp_instr_jump_if_not : public sp_instr_jump


class sp_instr_preturn : public sp_instr
{
  sp_instr_preturn(const sp_instr_preturn &);	/**< Prevent use of these */
  void operator=(sp_instr_preturn &);

public:

  sp_instr_preturn(uint ip, sp_pcontext *ctx)
    : sp_instr(ip, ctx)
  {}

  virtual ~sp_instr_preturn() = default;

  virtual int execute(THD *thd, uint *nextp);

  virtual void print(String *str);

  virtual uint opt_mark(sp_head *sp, List<sp_instr> *leads)
  {
    marked= 1;
    return UINT_MAX;
  }

public:
  virtual PSI_statement_info* get_psi_info() { return & psi_info; }
  static PSI_statement_info psi_info;
}; // class sp_instr_preturn : public sp_instr


class sp_instr_freturn : public sp_instr
{
  sp_instr_freturn(const sp_instr_freturn &);	/**< Prevent use of these */
  void operator=(sp_instr_freturn &);

public:

  sp_instr_freturn(uint ip, sp_pcontext *ctx,
		   Item *val, const Type_handler *handler, LEX *lex)
    : sp_instr(ip, ctx), m_value(val), m_type_handler(handler),
      m_lex_keeper(lex, TRUE)
  {}

  virtual ~sp_instr_freturn() = default;

  virtual int execute(THD *thd, uint *nextp);

  virtual int exec_core(THD *thd, uint *nextp);

  virtual void print(String *str);

  virtual uint opt_mark(sp_head *sp, List<sp_instr> *leads)
  {
    marked= 1;
    return UINT_MAX;
  }

protected:

  Item *m_value;
  const Type_handler *m_type_handler;
  sp_lex_keeper m_lex_keeper;

public:
  virtual PSI_statement_info* get_psi_info() { return & psi_info; }
  static PSI_statement_info psi_info;
}; // class sp_instr_freturn : public sp_instr


class sp_instr_hpush_jump : public sp_instr_jump
{
  sp_instr_hpush_jump(const sp_instr_hpush_jump &); /**< Prevent use of these */
  void operator=(sp_instr_hpush_jump &);

public:

  sp_instr_hpush_jump(uint ip,
                      sp_pcontext *ctx,
                      sp_handler *handler)
   :sp_instr_jump(ip, ctx),
    m_handler(handler),
    m_opt_hpop(0),
    m_frame(ctx->current_var_count())
  {
    DBUG_ASSERT(m_handler->condition_values.elements == 0);
  }

  virtual ~sp_instr_hpush_jump()
  {
    m_handler->condition_values.empty();
    m_handler= NULL;
  }

  virtual int execute(THD *thd, uint *nextp);

  virtual void print(String *str);

  virtual uint opt_mark(sp_head *sp, List<sp_instr> *leads);

  /** Override sp_instr_jump's shortcut; we stop here. */
  virtual uint opt_shortcut_jump(sp_head *sp, sp_instr *start)
  {
    return m_ip;
  }

  virtual void backpatch(uint dest, sp_pcontext *dst_ctx)
  {
    DBUG_ASSERT(!m_dest || !m_opt_hpop);
    if (!m_dest)
      m_dest= dest;
    else
      m_opt_hpop= dest;
  }

  void add_condition(sp_condition_value *condition_value)
  { m_handler->condition_values.push_back(condition_value); }

  sp_handler *get_handler()
  { return m_handler; }

private:
  /// Handler.
  sp_handler *m_handler;

  /// hpop marking end of handler scope.
  uint m_opt_hpop;

  // This attribute is needed for SHOW PROCEDURE CODE only (i.e. it's needed in
  // debug version only). It's used in print().
  uint m_frame;

public:
  virtual PSI_statement_info* get_psi_info() { return & psi_info; }
  static PSI_statement_info psi_info;
}; // class sp_instr_hpush_jump : public sp_instr_jump


class sp_instr_hpop : public sp_instr
{
  sp_instr_hpop(const sp_instr_hpop &);	/**< Prevent use of these */
  void operator=(sp_instr_hpop &);

public:

  sp_instr_hpop(uint ip, sp_pcontext *ctx, uint count)
    : sp_instr(ip, ctx), m_count(count)
  {}

  virtual ~sp_instr_hpop() = default;

  void update_count(uint count)
  {
    m_count= count;
  }

  virtual int execute(THD *thd, uint *nextp);

  virtual void print(String *str);

private:

  uint m_count;

public:
  virtual PSI_statement_info* get_psi_info() { return & psi_info; }
  static PSI_statement_info psi_info;
}; // class sp_instr_hpop : public sp_instr


class sp_instr_hreturn : public sp_instr_jump
{
  sp_instr_hreturn(const sp_instr_hreturn &);	/**< Prevent use of these */
  void operator=(sp_instr_hreturn &);

public:

  sp_instr_hreturn(uint ip, sp_pcontext *ctx)
   :sp_instr_jump(ip, ctx),
    m_frame(ctx->current_var_count())
  {}

  virtual ~sp_instr_hreturn() = default;

  virtual int execute(THD *thd, uint *nextp);

  virtual void print(String *str);

  /* This instruction will not be short cut optimized. */
  virtual uint opt_shortcut_jump(sp_head *sp, sp_instr *start)
  {
    return m_ip;
  }

  virtual uint opt_mark(sp_head *sp, List<sp_instr> *leads);

private:

  uint m_frame;

public:
  virtual PSI_statement_info* get_psi_info() { return & psi_info; }
  static PSI_statement_info psi_info;
}; // class sp_instr_hreturn : public sp_instr_jump


/** This is DECLARE CURSOR */
class sp_instr_cpush : public sp_instr, public sp_cursor
{
  sp_instr_cpush(const sp_instr_cpush &); /**< Prevent use of these */
  void operator=(sp_instr_cpush &);

public:

  sp_instr_cpush(uint ip, sp_pcontext *ctx, LEX *lex, uint offset)
    : sp_instr(ip, ctx), m_lex_keeper(lex, TRUE), m_cursor(offset)
  {}

  virtual ~sp_instr_cpush() = default;

  int execute(THD *thd, uint *nextp) override;

  void print(String *str) override;

  /**
    This call is used to cleanup the instruction when a sensitive
    cursor is closed. For now stored procedures always use materialized
    cursors and the call is not used.
  */
  virtual bool cleanup_stmt(bool /*restore_set_statement_vars*/) override
  { return false; }
private:

  sp_lex_keeper m_lex_keeper;
  uint m_cursor;                /**< Frame offset (for debugging) */

public:
  PSI_statement_info* get_psi_info() override { return & psi_info; }
  static PSI_statement_info psi_info;
}; // class sp_instr_cpush : public sp_instr


class sp_instr_cpop : public sp_instr
{
  sp_instr_cpop(const sp_instr_cpop &); /**< Prevent use of these */
  void operator=(sp_instr_cpop &);

public:

  sp_instr_cpop(uint ip, sp_pcontext *ctx, uint count)
    : sp_instr(ip, ctx), m_count(count)
  {}

  virtual ~sp_instr_cpop() = default;

  void update_count(uint count)
  {
    m_count= count;
  }

  virtual int execute(THD *thd, uint *nextp);

  virtual void print(String *str);

private:

  uint m_count;

public:
  virtual PSI_statement_info* get_psi_info() { return & psi_info; }
  static PSI_statement_info psi_info;
}; // class sp_instr_cpop : public sp_instr


class sp_instr_copen : public sp_instr
{
  sp_instr_copen(const sp_instr_copen &); /**< Prevent use of these */
  void operator=(sp_instr_copen &);

public:

  sp_instr_copen(uint ip, sp_pcontext *ctx, uint c)
    : sp_instr(ip, ctx), m_cursor(c)
  {}

  virtual ~sp_instr_copen() = default;

  virtual int execute(THD *thd, uint *nextp);

  virtual int exec_core(THD *thd, uint *nextp);

  virtual void print(String *str);

private:

  uint m_cursor;		///< Stack index

public:
  virtual PSI_statement_info* get_psi_info() { return & psi_info; }
  static PSI_statement_info psi_info;
}; // class sp_instr_copen : public sp_instr_stmt


/**
  Initialize the structure of a cursor%ROWTYPE variable
  from the LEX containing the cursor SELECT statement.
*/
class sp_instr_cursor_copy_struct: public sp_instr
{
  /**< Prevent use of these */
  sp_instr_cursor_copy_struct(const sp_instr_cursor_copy_struct &);
  void operator=(sp_instr_cursor_copy_struct &);
  sp_lex_keeper m_lex_keeper;
  uint m_cursor;
  uint m_var;
public:
  sp_instr_cursor_copy_struct(uint ip, sp_pcontext *ctx, uint coffs,
                              sp_lex_cursor *lex, uint voffs)
    : sp_instr(ip, ctx), m_lex_keeper(lex, FALSE),
      m_cursor(coffs),
      m_var(voffs)
  {}
  virtual ~sp_instr_cursor_copy_struct() = default;
  virtual int execute(THD *thd, uint *nextp);
  virtual int exec_core(THD *thd, uint *nextp);
  virtual void print(String *str);

public:
  virtual PSI_statement_info* get_psi_info() { return & psi_info; }
  static PSI_statement_info psi_info;
};


class sp_instr_cclose : public sp_instr
{
  sp_instr_cclose(const sp_instr_cclose &); /**< Prevent use of these */
  void operator=(sp_instr_cclose &);

public:

  sp_instr_cclose(uint ip, sp_pcontext *ctx, uint c)
    : sp_instr(ip, ctx), m_cursor(c)
  {}

  virtual ~sp_instr_cclose() = default;

  virtual int execute(THD *thd, uint *nextp);

  virtual void print(String *str);

private:

  uint m_cursor;

public:
  virtual PSI_statement_info* get_psi_info() { return & psi_info; }
  static PSI_statement_info psi_info;
}; // class sp_instr_cclose : public sp_instr


class sp_instr_cfetch : public sp_instr
{
  sp_instr_cfetch(const sp_instr_cfetch &); /**< Prevent use of these */
  void operator=(sp_instr_cfetch &);

public:

  sp_instr_cfetch(uint ip, sp_pcontext *ctx, uint c, bool error_on_no_data)
    : sp_instr(ip, ctx), m_cursor(c), m_error_on_no_data(error_on_no_data)
  {
    m_varlist.empty();
  }

  virtual ~sp_instr_cfetch() = default;

  virtual int execute(THD *thd, uint *nextp);

  virtual void print(String *str);

  void add_to_varlist(sp_variable *var)
  {
    m_varlist.push_back(var);
  }

private:

  uint m_cursor;
  List<sp_variable> m_varlist;
  bool m_error_on_no_data;

public:
  virtual PSI_statement_info* get_psi_info() { return & psi_info; }
  static PSI_statement_info psi_info;
}; // class sp_instr_cfetch : public sp_instr

/*
This class is created for the special fetch instruction
FETCH GROUP NEXT ROW, used in the user-defined aggregate
functions
*/

class sp_instr_agg_cfetch : public sp_instr
{
  sp_instr_agg_cfetch(const sp_instr_cfetch &); /**< Prevent use of these */
  void operator=(sp_instr_cfetch &);

public:

  sp_instr_agg_cfetch(uint ip, sp_pcontext *ctx)
    : sp_instr(ip, ctx){}

  virtual ~sp_instr_agg_cfetch() = default;

  virtual int execute(THD *thd, uint *nextp);

  virtual void print(String *str);

public:
  virtual PSI_statement_info* get_psi_info() { return & psi_info; }
  static PSI_statement_info psi_info;
}; // class sp_instr_agg_cfetch : public sp_instr




class sp_instr_error : public sp_instr
{
  sp_instr_error(const sp_instr_error &); /**< Prevent use of these */
  void operator=(sp_instr_error &);

public:

  sp_instr_error(uint ip, sp_pcontext *ctx, int errcode)
    : sp_instr(ip, ctx), m_errcode(errcode)
  {}

  virtual ~sp_instr_error() = default;

  virtual int execute(THD *thd, uint *nextp);

  virtual void print(String *str);

  virtual uint opt_mark(sp_head *sp, List<sp_instr> *leads)
  {
    marked= 1;
    return UINT_MAX;
  }

private:

  int m_errcode;

public:
  virtual PSI_statement_info* get_psi_info() { return & psi_info; }
  static PSI_statement_info psi_info;
}; // class sp_instr_error : public sp_instr


class sp_instr_set_case_expr : public sp_instr_opt_meta
{
public:

  sp_instr_set_case_expr(uint ip, sp_pcontext *ctx, uint case_expr_id,
                         Item *case_expr, LEX *lex)
    : sp_instr_opt_meta(ip, ctx),
      m_case_expr_id(case_expr_id), m_case_expr(case_expr),
      m_lex_keeper(lex, TRUE)
  {}

  virtual ~sp_instr_set_case_expr() = default;

  virtual int execute(THD *thd, uint *nextp);

  virtual int exec_core(THD *thd, uint *nextp);

  virtual void print(String *str);

  virtual uint opt_mark(sp_head *sp, List<sp_instr> *leads);

  virtual void opt_move(uint dst, List<sp_instr> *ibp);

  virtual void set_destination(uint old_dest, uint new_dest)
  {
    if (m_cont_dest == old_dest)
      m_cont_dest= new_dest;
  }

private:

  uint m_case_expr_id;
  Item *m_case_expr;
  sp_lex_keeper m_lex_keeper;

public:
  virtual PSI_statement_info* get_psi_info() { return & psi_info; }
  static PSI_statement_info psi_info;
}; // class sp_instr_set_case_expr : public sp_instr_opt_meta

bool check_show_routine_access(THD *thd, sp_head *sp, bool *full_access);

#ifndef NO_EMBEDDED_ACCESS_CHECKS
bool
sp_change_security_context(THD *thd, sp_head *sp,
                           Security_context **backup);
void
sp_restore_security_context(THD *thd, Security_context *backup);

bool
set_routine_security_ctx(THD *thd, sp_head *sp, Security_context **save_ctx);
#endif /* NO_EMBEDDED_ACCESS_CHECKS */

TABLE_LIST *
sp_add_to_query_tables(THD *thd, LEX *lex,
		       const LEX_CSTRING *db, const LEX_CSTRING *name,
                       thr_lock_type locktype,
                       enum_mdl_type mdl_type);

/**
  @} (end of group Stored_Routines)
*/

#endif /* _SP_HEAD_H_ */