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
2189
2190
2191
2192
2193
2194
2195
2196
2197
2198
2199
2200
2201
2202
2203
2204
2205
2206
2207
2208
2209
2210
2211
2212
2213
2214
2215
2216
2217
2218
2219
2220
2221
2222
2223
2224
2225
2226
2227
2228
2229
2230
2231
2232
2233
2234
2235
2236
2237
2238
2239
2240
2241
2242
2243
2244
2245
2246
2247
2248
2249
2250
2251
2252
2253
2254
2255
2256
2257
2258
2259
2260
2261
2262
2263
2264
2265
2266
2267
2268
2269
2270
2271
2272
2273
2274
2275
2276
2277
2278
2279
2280
2281
2282
2283
2284
2285
2286
2287
2288
2289
2290
2291
2292
2293
2294
2295
2296
2297
2298
2299
2300
2301
2302
2303
2304
2305
2306
2307
2308
2309
2310
2311
2312
2313
2314
2315
2316
2317
2318
2319
2320
2321
2322
2323
2324
2325
2326
2327
2328
2329
2330
2331
2332
2333
2334
2335
2336
2337
2338
2339
2340
2341
2342
2343
2344
2345
2346
2347
2348
2349
2350
2351
2352
2353
2354
2355
2356
2357
2358
2359
2360
2361
2362
2363
2364
2365
2366
2367
2368
2369
2370
2371
2372
2373
2374
2375
2376
2377
2378
2379
2380
2381
2382
2383
2384
2385
2386
2387
2388
2389
2390
2391
2392
2393
2394
2395
2396
2397
2398
2399
2400
2401
2402
2403
2404
2405
2406
2407
2408
2409
2410
2411
2412
2413
2414
2415
2416
2417
2418
2419
2420
2421
2422
2423
2424
2425
2426
2427
2428
2429
2430
2431
2432
2433
2434
2435
2436
2437
2438
2439
2440
2441
2442
2443
2444
2445
2446
2447
2448
2449
2450
2451
2452
2453
2454
2455
2456
2457
2458
2459
2460
2461
2462
2463
2464
2465
2466
2467
2468
2469
2470
2471
2472
2473
2474
2475
2476
2477
2478
2479
2480
2481
2482
2483
2484
2485
2486
2487
2488
2489
2490
2491
2492
2493
2494
2495
2496
2497
2498
2499
2500
2501
2502
2503
2504
2505
2506
2507
2508
2509
2510
2511
2512
2513
2514
2515
2516
2517
2518
2519
2520
2521
2522
2523
2524
2525
2526
2527
2528
2529
2530
2531
2532
2533
2534
2535
2536
2537
2538
2539
2540
2541
2542
2543
2544
2545
2546
2547
2548
2549
2550
2551
2552
2553
2554
2555
2556
2557
2558
2559
2560
2561
2562
2563
2564
2565
2566
2567
2568
2569
2570
2571
2572
2573
2574
2575
2576
2577
2578
2579
2580
2581
2582
2583
2584
2585
2586
2587
2588
2589
2590
2591
2592
2593
2594
2595
2596
2597
2598
2599
2600
2601
2602
2603
2604
2605
2606
2607
2608
2609
2610
2611
2612
2613
2614
2615
2616
2617
2618
2619
2620
2621
2622
2623
2624
2625
2626
2627
2628
2629
2630
2631
2632
2633
2634
2635
2636
2637
2638
2639
2640
2641
2642
2643
2644
2645
2646
2647
2648
2649
2650
2651
2652
2653
2654
2655
2656
2657
2658
2659
2660
2661
2662
2663
2664
2665
2666
2667
2668
2669
2670
2671
2672
2673
2674
2675
2676
2677
2678
2679
2680
2681
2682
2683
2684
2685
2686
2687
2688
2689
2690
2691
2692
2693
2694
2695
2696
2697
2698
2699
2700
2701
2702
2703
2704
2705
2706
2707
2708
2709
2710
2711
2712
2713
2714
2715
2716
2717
2718
2719
2720
2721
2722
2723
2724
2725
2726
2727
2728
2729
2730
2731
2732
2733
2734
2735
2736
2737
2738
2739
2740
2741
2742
2743
2744
2745
2746
2747
2748
2749
2750
2751
2752
2753
2754
2755
2756
2757
2758
2759
2760
2761
2762
2763
2764
2765
2766
2767
2768
2769
2770
2771
2772
2773
2774
2775
2776
2777
2778
2779
2780
2781
2782
2783
2784
2785
2786
2787
2788
2789
2790
2791
2792
2793
2794
2795
2796
2797
2798
2799
2800
2801
2802
2803
2804
2805
2806
2807
2808
2809
2810
2811
2812
2813
2814
2815
2816
2817
2818
2819
2820
2821
2822
2823
2824
2825
2826
2827
2828
2829
2830
2831
2832
2833
2834
2835
2836
2837
2838
2839
2840
2841
2842
2843
2844
2845
2846
2847
2848
2849
2850
2851
2852
2853
2854
2855
2856
2857
2858
2859
2860
2861
2862
2863
2864
2865
2866
2867
2868
2869
2870
2871
2872
2873
2874
2875
2876
2877
2878
2879
2880
2881
2882
2883
2884
2885
2886
2887
2888
2889
2890
2891
2892
2893
2894
2895
2896
2897
2898
2899
2900
2901
2902
2903
2904
2905
2906
2907
2908
2909
2910
2911
2912
2913
2914
2915
2916
2917
2918
2919
2920
2921
2922
2923
2924
2925
2926
2927
2928
2929
2930
2931
2932
2933
2934
2935
2936
2937
2938
2939
2940
2941
2942
2943
2944
2945
2946
2947
2948
2949
2950
2951
2952
2953
2954
2955
2956
2957
2958
2959
2960
2961
2962
2963
2964
2965
2966
2967
2968
2969
2970
2971
2972
2973
2974
2975
2976
2977
2978
2979
2980
2981
2982
2983
2984
2985
2986
2987
2988
2989
2990
2991
2992
2993
2994
2995
2996
2997
2998
2999
3000
3001
3002
3003
3004
3005
3006
3007
3008
3009
3010
3011
3012
3013
3014
3015
3016
3017
3018
3019
3020
3021
3022
3023
3024
3025
3026
3027
3028
3029
3030
3031
3032
3033
3034
3035
3036
3037
3038
3039
3040
3041
3042
|
/* Copyright (C) 1995-2002 MySQL AB
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; either version 2 of the License, or
(at your option) any later version.
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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */
/**********************************************************************
This file contains the implementation of prepared statements.
When one prepares a statement:
- Server gets the query from client with command 'COM_STMT_PREPARE';
in the following format:
[COM_STMT_PREPARE:1] [query]
- Parse the query and recognize any parameter markers '?' and
store its information list in lex->param_list
- Allocate a new statement for this prepare; and keep this in
'thd->stmt_map'.
- Without executing the query, return back to client the total
number of parameters along with result-set metadata information
(if any) in the following format:
[STMT_ID:4]
[Column_count:2]
[Param_count:2]
[Params meta info (stubs only for now)] (if Param_count > 0)
[Columns meta info] (if Column_count > 0)
When one executes a statement:
- Server gets the command 'COM_STMT_EXECUTE' to execute the
previously prepared query. If there are any parameter markers, then the
client will send the data in the following format:
[COM_STMT_EXECUTE:1]
[STMT_ID:4]
[NULL_BITS:(param_count+7)/8)]
[TYPES_SUPPLIED_BY_CLIENT(0/1):1]
[[length]data]
[[length]data] .. [[length]data].
(Note: Except for string/binary types; all other types will not be
supplied with length field)
- If it is a first execute or types of parameters were altered by client,
then setup the conversion routines.
- Assign parameter items from the supplied data.
- Execute the query without re-parsing and send back the results
to client
When one supplies long data for a placeholder:
- Server gets the long data in pieces with command type
'COM_STMT_SEND_LONG_DATA'.
- The packet recieved will have the format as:
[COM_STMT_SEND_LONG_DATA:1][STMT_ID:4][parameter_number:2][data]
- data from the packet is appended to the long data value buffer for this
placeholder.
- It's up to the client to stop supplying data chunks at any point. The
server doesn't care; also, the server doesn't notify the client whether
it got the data or not; if there is any error, then it will be returned
at statement execute.
***********************************************************************/
#include "mysql_priv.h"
#include "sql_select.h" // for JOIN
#include "sql_cursor.h"
#include "sp_head.h"
#include "sp.h"
#include "sp_cache.h"
#ifdef EMBEDDED_LIBRARY
/* include MYSQL_BIND headers */
#include <mysql.h>
#else
#include <mysql_com.h>
#endif
/* A result class used to send cursor rows using the binary protocol. */
class Select_fetch_protocol_prep: public select_send
{
Protocol_prep protocol;
public:
Select_fetch_protocol_prep(THD *thd);
virtual bool send_fields(List<Item> &list, uint flags);
virtual bool send_data(List<Item> &items);
virtual bool send_eof();
#ifdef EMBEDDED_LIBRARY
void begin_dataset()
{
protocol.begin_dataset();
}
#endif
};
/******************************************************************************
Prepared_statement: a statement that can contain placeholders
******************************************************************************/
class Prepared_statement: public Statement
{
public:
enum flag_values
{
IS_IN_USE= 1
};
THD *thd;
Select_fetch_protocol_prep result;
Protocol *protocol;
Item_param **param_array;
uint param_count;
uint last_errno;
uint flags;
char last_error[MYSQL_ERRMSG_SIZE];
#ifndef EMBEDDED_LIBRARY
bool (*set_params)(Prepared_statement *st, uchar *data, uchar *data_end,
uchar *read_pos, String *expanded_query);
#else
bool (*set_params_data)(Prepared_statement *st, String *expanded_query);
#endif
bool (*set_params_from_vars)(Prepared_statement *stmt,
List<LEX_STRING>& varnames,
String *expanded_query);
public:
Prepared_statement(THD *thd_arg, Protocol *protocol_arg);
virtual ~Prepared_statement();
void setup_set_params();
virtual Query_arena::Type type() const;
virtual void cleanup_stmt();
bool set_name(LEX_STRING *name);
inline void close_cursor() { delete cursor; cursor= 0; }
bool prepare(const char *packet, uint packet_length);
bool execute(String *expanded_query, bool open_cursor);
/* Destroy this statement */
bool deallocate();
};
/******************************************************************************
Implementation
******************************************************************************/
inline bool is_param_null(const uchar *pos, ulong param_no)
{
return pos[param_no/8] & (1 << (param_no & 7));
}
/*
Find a prepared statement in the statement map by id.
SYNOPSIS
find_prepared_statement()
thd thread handle
id statement id
where the place from which this function is called (for
error reporting).
DESCRIPTION
Try to find a prepared statement and set THD error if it's not found.
RETURN VALUE
0 if the statement was not found, a pointer otherwise.
*/
static Prepared_statement *
find_prepared_statement(THD *thd, ulong id, const char *where)
{
/*
To strictly separate namespaces of SQL prepared statements and C API
prepared statements find() will return 0 if there is a named prepared
statement with such id.
*/
Statement *stmt= thd->stmt_map.find(id);
if (stmt == 0 || stmt->type() != Query_arena::PREPARED_STATEMENT)
{
char llbuf[22];
my_error(ER_UNKNOWN_STMT_HANDLER, MYF(0), sizeof(llbuf), llstr(id, llbuf),
where);
return 0;
}
return (Prepared_statement *) stmt;
}
/*
Send prepared statement id and metadata to the client after prepare.
SYNOPSIS
send_prep_stmt()
RETURN VALUE
0 in case of success, 1 otherwise
*/
#ifndef EMBEDDED_LIBRARY
static bool send_prep_stmt(Prepared_statement *stmt, uint columns)
{
NET *net= &stmt->thd->net;
char buff[12];
uint tmp;
DBUG_ENTER("send_prep_stmt");
buff[0]= 0; /* OK packet indicator */
int4store(buff+1, stmt->id);
int2store(buff+5, columns);
int2store(buff+7, stmt->param_count);
buff[9]= 0; // Guard against a 4.1 client
tmp= min(stmt->thd->total_warn_count, 65535);
int2store(buff+10, tmp);
/*
Send types and names of placeholders to the client
XXX: fix this nasty upcast from List<Item_param> to List<Item>
*/
DBUG_RETURN(my_net_write(net, buff, sizeof(buff)) ||
(stmt->param_count &&
stmt->thd->protocol_simple.send_fields((List<Item> *)
&stmt->lex->param_list,
Protocol::SEND_EOF)));
}
#else
static bool send_prep_stmt(Prepared_statement *stmt,
uint columns __attribute__((unused)))
{
THD *thd= stmt->thd;
thd->client_stmt_id= stmt->id;
thd->client_param_count= stmt->param_count;
thd->clear_error();
return 0;
}
#endif /*!EMBEDDED_LIBRARY*/
/*
Read the length of the parameter data and return it back to
the caller.
SYNOPSIS
get_param_length()
packet a pointer to the data
len remaining packet length
DESCRIPTION
Read data length, position the packet to the first byte after it,
and return the length to the caller.
RETURN VALUE
Length of data piece.
*/
#ifndef EMBEDDED_LIBRARY
static ulong get_param_length(uchar **packet, ulong len)
{
reg1 uchar *pos= *packet;
if (len < 1)
return 0;
if (*pos < 251)
{
(*packet)++;
return (ulong) *pos;
}
if (len < 3)
return 0;
if (*pos == 252)
{
(*packet)+=3;
return (ulong) uint2korr(pos+1);
}
if (len < 4)
return 0;
if (*pos == 253)
{
(*packet)+=4;
return (ulong) uint3korr(pos+1);
}
if (len < 5)
return 0;
(*packet)+=9; // Must be 254 when here
/*
In our client-server protocol all numbers bigger than 2^24
stored as 8 bytes with uint8korr. Here we always know that
parameter length is less than 2^4 so don't look at the second
4 bytes. But still we need to obey the protocol hence 9 in the
assignment above.
*/
return (ulong) uint4korr(pos+1);
}
#else
#define get_param_length(packet, len) len
#endif /*!EMBEDDED_LIBRARY*/
/*
Data conversion routines.
SYNOPSIS
set_param_xx()
param parameter item
pos input data buffer
len length of data in the buffer
DESCRIPTION
All these functions read the data from pos, convert it to requested
type and assign to param; pos is advanced to predefined length.
Make a note that the NULL handling is examined at first execution
(i.e. when input types altered) and for all subsequent executions
we don't read any values for this.
RETURN VALUE
none
*/
static void set_param_tiny(Item_param *param, uchar **pos, ulong len)
{
#ifndef EMBEDDED_LIBRARY
if (len < 1)
return;
#endif
int8 value= (int8) **pos;
param->set_int(param->unsigned_flag ? (longlong) ((uint8) value) :
(longlong) value, 4);
*pos+= 1;
}
static void set_param_short(Item_param *param, uchar **pos, ulong len)
{
int16 value;
#ifndef EMBEDDED_LIBRARY
if (len < 2)
return;
value= sint2korr(*pos);
#else
shortget(value, *pos);
#endif
param->set_int(param->unsigned_flag ? (longlong) ((uint16) value) :
(longlong) value, 6);
*pos+= 2;
}
static void set_param_int32(Item_param *param, uchar **pos, ulong len)
{
int32 value;
#ifndef EMBEDDED_LIBRARY
if (len < 4)
return;
value= sint4korr(*pos);
#else
longget(value, *pos);
#endif
param->set_int(param->unsigned_flag ? (longlong) ((uint32) value) :
(longlong) value, 11);
*pos+= 4;
}
static void set_param_int64(Item_param *param, uchar **pos, ulong len)
{
longlong value;
#ifndef EMBEDDED_LIBRARY
if (len < 8)
return;
value= (longlong) sint8korr(*pos);
#else
longlongget(value, *pos);
#endif
param->set_int(value, 21);
*pos+= 8;
}
static void set_param_float(Item_param *param, uchar **pos, ulong len)
{
float data;
#ifndef EMBEDDED_LIBRARY
if (len < 4)
return;
float4get(data,*pos);
#else
floatget(data, *pos);
#endif
param->set_double((double) data);
*pos+= 4;
}
static void set_param_double(Item_param *param, uchar **pos, ulong len)
{
double data;
#ifndef EMBEDDED_LIBRARY
if (len < 8)
return;
float8get(data,*pos);
#else
doubleget(data, *pos);
#endif
param->set_double((double) data);
*pos+= 8;
}
static void set_param_decimal(Item_param *param, uchar **pos, ulong len)
{
ulong length= get_param_length(pos, len);
param->set_decimal((char*)*pos, length);
*pos+= length;
}
#ifndef EMBEDDED_LIBRARY
/*
Read date/time/datetime parameter values from network (binary
protocol). See writing counterparts of these functions in
libmysql.c (store_param_{time,date,datetime}).
*/
static void set_param_time(Item_param *param, uchar **pos, ulong len)
{
MYSQL_TIME tm;
ulong length= get_param_length(pos, len);
if (length >= 8)
{
uchar *to= *pos;
uint day;
tm.neg= (bool) to[0];
day= (uint) sint4korr(to+1);
tm.hour= (uint) to[5] + day * 24;
tm.minute= (uint) to[6];
tm.second= (uint) to[7];
tm.second_part= (length > 8) ? (ulong) sint4korr(to+8) : 0;
if (tm.hour > 838)
{
/* TODO: add warning 'Data truncated' here */
tm.hour= 838;
tm.minute= 59;
tm.second= 59;
}
tm.day= tm.year= tm.month= 0;
}
else
set_zero_time(&tm, MYSQL_TIMESTAMP_TIME);
param->set_time(&tm, MYSQL_TIMESTAMP_TIME,
MAX_TIME_WIDTH * MY_CHARSET_BIN_MB_MAXLEN);
*pos+= length;
}
static void set_param_datetime(Item_param *param, uchar **pos, ulong len)
{
MYSQL_TIME tm;
ulong length= get_param_length(pos, len);
if (length >= 4)
{
uchar *to= *pos;
tm.neg= 0;
tm.year= (uint) sint2korr(to);
tm.month= (uint) to[2];
tm.day= (uint) to[3];
if (length > 4)
{
tm.hour= (uint) to[4];
tm.minute= (uint) to[5];
tm.second= (uint) to[6];
}
else
tm.hour= tm.minute= tm.second= 0;
tm.second_part= (length > 7) ? (ulong) sint4korr(to+7) : 0;
}
else
set_zero_time(&tm, MYSQL_TIMESTAMP_DATETIME);
param->set_time(&tm, MYSQL_TIMESTAMP_DATETIME,
MAX_DATETIME_WIDTH * MY_CHARSET_BIN_MB_MAXLEN);
*pos+= length;
}
static void set_param_date(Item_param *param, uchar **pos, ulong len)
{
MYSQL_TIME tm;
ulong length= get_param_length(pos, len);
if (length >= 4)
{
uchar *to= *pos;
tm.year= (uint) sint2korr(to);
tm.month= (uint) to[2];
tm.day= (uint) to[3];
tm.hour= tm.minute= tm.second= 0;
tm.second_part= 0;
tm.neg= 0;
}
else
set_zero_time(&tm, MYSQL_TIMESTAMP_DATE);
param->set_time(&tm, MYSQL_TIMESTAMP_DATE,
MAX_DATE_WIDTH * MY_CHARSET_BIN_MB_MAXLEN);
*pos+= length;
}
#else/*!EMBEDDED_LIBRARY*/
void set_param_time(Item_param *param, uchar **pos, ulong len)
{
MYSQL_TIME tm= *((MYSQL_TIME*)*pos);
tm.hour+= tm.day * 24;
tm.day= tm.year= tm.month= 0;
if (tm.hour > 838)
{
/* TODO: add warning 'Data truncated' here */
tm.hour= 838;
tm.minute= 59;
tm.second= 59;
}
param->set_time(&tm, MYSQL_TIMESTAMP_TIME,
MAX_TIME_WIDTH * MY_CHARSET_BIN_MB_MAXLEN);
}
void set_param_datetime(Item_param *param, uchar **pos, ulong len)
{
MYSQL_TIME tm= *((MYSQL_TIME*)*pos);
tm.neg= 0;
param->set_time(&tm, MYSQL_TIMESTAMP_DATETIME,
MAX_DATETIME_WIDTH * MY_CHARSET_BIN_MB_MAXLEN);
}
void set_param_date(Item_param *param, uchar **pos, ulong len)
{
MYSQL_TIME *to= (MYSQL_TIME*)*pos;
param->set_time(to, MYSQL_TIMESTAMP_DATE,
MAX_DATE_WIDTH * MY_CHARSET_BIN_MB_MAXLEN);
}
#endif /*!EMBEDDED_LIBRARY*/
static void set_param_str(Item_param *param, uchar **pos, ulong len)
{
ulong length= get_param_length(pos, len);
param->set_str((const char *)*pos, length);
*pos+= length;
}
#undef get_param_length
static void setup_one_conversion_function(THD *thd, Item_param *param,
uchar param_type)
{
switch (param_type) {
case MYSQL_TYPE_TINY:
param->set_param_func= set_param_tiny;
param->item_type= Item::INT_ITEM;
param->item_result_type= INT_RESULT;
break;
case MYSQL_TYPE_SHORT:
param->set_param_func= set_param_short;
param->item_type= Item::INT_ITEM;
param->item_result_type= INT_RESULT;
break;
case MYSQL_TYPE_LONG:
param->set_param_func= set_param_int32;
param->item_type= Item::INT_ITEM;
param->item_result_type= INT_RESULT;
break;
case MYSQL_TYPE_LONGLONG:
param->set_param_func= set_param_int64;
param->item_type= Item::INT_ITEM;
param->item_result_type= INT_RESULT;
break;
case MYSQL_TYPE_FLOAT:
param->set_param_func= set_param_float;
param->item_type= Item::REAL_ITEM;
param->item_result_type= REAL_RESULT;
break;
case MYSQL_TYPE_DOUBLE:
param->set_param_func= set_param_double;
param->item_type= Item::REAL_ITEM;
param->item_result_type= REAL_RESULT;
break;
case MYSQL_TYPE_DECIMAL:
case MYSQL_TYPE_NEWDECIMAL:
param->set_param_func= set_param_decimal;
param->item_type= Item::DECIMAL_ITEM;
param->item_result_type= DECIMAL_RESULT;
break;
case MYSQL_TYPE_TIME:
param->set_param_func= set_param_time;
param->item_type= Item::STRING_ITEM;
param->item_result_type= STRING_RESULT;
break;
case MYSQL_TYPE_DATE:
param->set_param_func= set_param_date;
param->item_type= Item::STRING_ITEM;
param->item_result_type= STRING_RESULT;
break;
case MYSQL_TYPE_DATETIME:
case MYSQL_TYPE_TIMESTAMP:
param->set_param_func= set_param_datetime;
param->item_type= Item::STRING_ITEM;
param->item_result_type= STRING_RESULT;
break;
case MYSQL_TYPE_TINY_BLOB:
case MYSQL_TYPE_MEDIUM_BLOB:
case MYSQL_TYPE_LONG_BLOB:
case MYSQL_TYPE_BLOB:
param->set_param_func= set_param_str;
param->value.cs_info.character_set_of_placeholder= &my_charset_bin;
param->value.cs_info.character_set_client=
thd->variables.character_set_client;
DBUG_ASSERT(thd->variables.character_set_client);
param->value.cs_info.final_character_set_of_str_value= &my_charset_bin;
param->item_type= Item::STRING_ITEM;
param->item_result_type= STRING_RESULT;
break;
default:
/*
The client library ensures that we won't get any other typecodes
except typecodes above and typecodes for string types. Marking
label as 'default' lets us to handle malformed packets as well.
*/
{
CHARSET_INFO *fromcs= thd->variables.character_set_client;
CHARSET_INFO *tocs= thd->variables.collation_connection;
uint32 dummy_offset;
param->value.cs_info.character_set_of_placeholder= fromcs;
param->value.cs_info.character_set_client= fromcs;
/*
Setup source and destination character sets so that they
are different only if conversion is necessary: this will
make later checks easier.
*/
param->value.cs_info.final_character_set_of_str_value=
String::needs_conversion(0, fromcs, tocs, &dummy_offset) ?
tocs : fromcs;
param->set_param_func= set_param_str;
/*
Exact value of max_length is not known unless data is converted to
charset of connection, so we have to set it later.
*/
param->item_type= Item::STRING_ITEM;
param->item_result_type= STRING_RESULT;
}
}
param->param_type= (enum enum_field_types) param_type;
}
#ifndef EMBEDDED_LIBRARY
/*
Routines to assign parameters from data supplied by the client.
DESCRIPTION
Update the parameter markers by reading data from the packet and
and generate a valid query for logging.
NOTES
This function, along with other _withlog functions is called when one of
binary, slow or general logs is open. Logging of prepared statements in
all cases is performed by means of conventional queries: if parameter
data was supplied from C API, each placeholder in the query is
replaced with its actual value; if we're logging a [Dynamic] SQL
prepared statement, parameter markers are replaced with variable names.
Example:
mysql_stmt_prepare("UPDATE t1 SET a=a*1.25 WHERE a=?")
--> general logs gets [Prepare] UPDATE t1 SET a*1.25 WHERE a=?"
mysql_stmt_execute(stmt);
--> general and binary logs get
[Execute] UPDATE t1 SET a*1.25 WHERE a=1"
If a statement has been prepared using SQL syntax:
PREPARE stmt FROM "UPDATE t1 SET a=a*1.25 WHERE a=?"
--> general log gets
[Query] PREPARE stmt FROM "UPDATE ..."
EXECUTE stmt USING @a
--> general log gets
[Query] EXECUTE stmt USING @a;
RETURN VALUE
0 if success, 1 otherwise
*/
static bool insert_params_withlog(Prepared_statement *stmt, uchar *null_array,
uchar *read_pos, uchar *data_end,
String *query)
{
THD *thd= stmt->thd;
Item_param **begin= stmt->param_array;
Item_param **end= begin + stmt->param_count;
uint32 length= 0;
String str;
const String *res;
DBUG_ENTER("insert_params_withlog");
if (query->copy(stmt->query, stmt->query_length, default_charset_info))
DBUG_RETURN(1);
for (Item_param **it= begin; it < end; ++it)
{
Item_param *param= *it;
if (param->state != Item_param::LONG_DATA_VALUE)
{
if (is_param_null(null_array, it - begin))
param->set_null();
else
{
if (read_pos >= data_end)
DBUG_RETURN(1);
param->set_param_func(param, &read_pos, data_end - read_pos);
}
}
res= param->query_val_str(&str);
if (param->convert_str_value(thd))
DBUG_RETURN(1); /* out of memory */
if (query->replace(param->pos_in_query+length, 1, *res))
DBUG_RETURN(1);
length+= res->length()-1;
}
DBUG_RETURN(0);
}
static bool insert_params(Prepared_statement *stmt, uchar *null_array,
uchar *read_pos, uchar *data_end,
String *expanded_query)
{
Item_param **begin= stmt->param_array;
Item_param **end= begin + stmt->param_count;
DBUG_ENTER("insert_params");
for (Item_param **it= begin; it < end; ++it)
{
Item_param *param= *it;
if (param->state != Item_param::LONG_DATA_VALUE)
{
if (is_param_null(null_array, it - begin))
param->set_null();
else
{
if (read_pos >= data_end)
DBUG_RETURN(1);
param->set_param_func(param, &read_pos, data_end - read_pos);
}
}
if (param->convert_str_value(stmt->thd))
DBUG_RETURN(1); /* out of memory */
}
DBUG_RETURN(0);
}
static bool setup_conversion_functions(Prepared_statement *stmt,
uchar **data, uchar *data_end)
{
/* skip null bits */
uchar *read_pos= *data + (stmt->param_count+7) / 8;
DBUG_ENTER("setup_conversion_functions");
if (*read_pos++) //types supplied / first execute
{
/*
First execute or types altered by the client, setup the
conversion routines for all parameters (one time)
*/
Item_param **it= stmt->param_array;
Item_param **end= it + stmt->param_count;
THD *thd= stmt->thd;
for (; it < end; ++it)
{
ushort typecode;
const uint signed_bit= 1 << 15;
if (read_pos >= data_end)
DBUG_RETURN(1);
typecode= sint2korr(read_pos);
read_pos+= 2;
(**it).unsigned_flag= test(typecode & signed_bit);
setup_one_conversion_function(thd, *it, (uchar) (typecode & ~signed_bit));
}
}
*data= read_pos;
DBUG_RETURN(0);
}
#else
/*
Embedded counterparts of parameter assignment routines.
DESCRIPTION
The main difference between the embedded library and the server is
that in embedded case we don't serialize/deserialize parameters data.
Additionally, for unknown reason, the client-side flag raised for
changed types of placeholders is ignored and we simply setup conversion
functions at each execute (TODO: fix).
*/
static bool emb_insert_params(Prepared_statement *stmt, String *expanded_query)
{
THD *thd= stmt->thd;
Item_param **it= stmt->param_array;
Item_param **end= it + stmt->param_count;
MYSQL_BIND *client_param= stmt->thd->client_params;
DBUG_ENTER("emb_insert_params");
for (; it < end; ++it, ++client_param)
{
Item_param *param= *it;
setup_one_conversion_function(thd, param, client_param->buffer_type);
if (param->state != Item_param::LONG_DATA_VALUE)
{
if (*client_param->is_null)
param->set_null();
else
{
uchar *buff= (uchar*) client_param->buffer;
param->unsigned_flag= client_param->is_unsigned;
param->set_param_func(param, &buff,
client_param->length ?
*client_param->length :
client_param->buffer_length);
}
}
if (param->convert_str_value(thd))
DBUG_RETURN(1); /* out of memory */
}
DBUG_RETURN(0);
}
static bool emb_insert_params_withlog(Prepared_statement *stmt, String *query)
{
THD *thd= stmt->thd;
Item_param **it= stmt->param_array;
Item_param **end= it + stmt->param_count;
MYSQL_BIND *client_param= thd->client_params;
String str;
const String *res;
uint32 length= 0;
DBUG_ENTER("emb_insert_params_withlog");
if (query->copy(stmt->query, stmt->query_length, default_charset_info))
DBUG_RETURN(1);
for (; it < end; ++it, ++client_param)
{
Item_param *param= *it;
setup_one_conversion_function(thd, param, client_param->buffer_type);
if (param->state != Item_param::LONG_DATA_VALUE)
{
if (*client_param->is_null)
param->set_null();
else
{
uchar *buff= (uchar*)client_param->buffer;
param->unsigned_flag= client_param->is_unsigned;
param->set_param_func(param, &buff,
client_param->length ?
*client_param->length :
client_param->buffer_length);
}
}
res= param->query_val_str(&str);
if (param->convert_str_value(thd))
DBUG_RETURN(1); /* out of memory */
if (query->replace(param->pos_in_query+length, 1, *res))
DBUG_RETURN(1);
length+= res->length()-1;
}
DBUG_RETURN(0);
}
#endif /*!EMBEDDED_LIBRARY*/
/*
Assign prepared statement parameters from user variables.
SYNOPSIS
insert_params_from_vars()
stmt Statement
varnames List of variables. Caller must ensure that number of variables
in the list is equal to number of statement parameters
query Ignored
*/
static bool insert_params_from_vars(Prepared_statement *stmt,
List<LEX_STRING>& varnames,
String *query __attribute__((unused)))
{
Item_param **begin= stmt->param_array;
Item_param **end= begin + stmt->param_count;
user_var_entry *entry;
LEX_STRING *varname;
List_iterator<LEX_STRING> var_it(varnames);
DBUG_ENTER("insert_params_from_vars");
for (Item_param **it= begin; it < end; ++it)
{
Item_param *param= *it;
varname= var_it++;
entry= (user_var_entry*)hash_search(&stmt->thd->user_vars,
(byte*) varname->str,
varname->length);
if (param->set_from_user_var(stmt->thd, entry) ||
param->convert_str_value(stmt->thd))
DBUG_RETURN(1);
}
DBUG_RETURN(0);
}
/*
Do the same as insert_params_from_vars but also construct query text for
binary log.
SYNOPSIS
insert_params_from_vars()
stmt Prepared statement
varnames List of variables. Caller must ensure that number of variables
in the list is equal to number of statement parameters
query The query with parameter markers replaced with corresponding
user variables that were used to execute the query.
*/
static bool insert_params_from_vars_with_log(Prepared_statement *stmt,
List<LEX_STRING>& varnames,
String *query)
{
Item_param **begin= stmt->param_array;
Item_param **end= begin + stmt->param_count;
user_var_entry *entry;
LEX_STRING *varname;
List_iterator<LEX_STRING> var_it(varnames);
String buf;
const String *val;
uint32 length= 0;
DBUG_ENTER("insert_params_from_vars");
if (query->copy(stmt->query, stmt->query_length, default_charset_info))
DBUG_RETURN(1);
for (Item_param **it= begin; it < end; ++it)
{
Item_param *param= *it;
varname= var_it++;
if (get_var_with_binlog(stmt->thd, stmt->lex->sql_command,
*varname, &entry))
DBUG_RETURN(1);
if (param->set_from_user_var(stmt->thd, entry))
DBUG_RETURN(1);
/* Insert @'escaped-varname' instead of parameter in the query */
if (entry)
{
char *begin, *ptr;
buf.length(0);
if (buf.reserve(entry->name.length*2+3))
DBUG_RETURN(1);
begin= ptr= buf.c_ptr_quick();
*ptr++= '@';
*ptr++= '\'';
ptr+= escape_string_for_mysql(&my_charset_utf8_general_ci,
ptr, 0, entry->name.str,
entry->name.length);
*ptr++= '\'';
buf.length(ptr - begin);
val= &buf;
}
else
val= &my_null_string;
if (param->convert_str_value(stmt->thd))
DBUG_RETURN(1); /* out of memory */
if (query->replace(param->pos_in_query+length, 1, *val))
DBUG_RETURN(1);
length+= val->length()-1;
}
DBUG_RETURN(0);
}
/*
Validate INSERT statement.
SYNOPSIS
mysql_test_insert()
stmt prepared statement
tables global/local table list
RETURN VALUE
FALSE success
TRUE error, error message is set in THD
*/
static bool mysql_test_insert(Prepared_statement *stmt,
TABLE_LIST *table_list,
List<Item> &fields,
List<List_item> &values_list,
List<Item> &update_fields,
List<Item> &update_values,
enum_duplicates duplic)
{
THD *thd= stmt->thd;
LEX *lex= stmt->lex;
List_iterator_fast<List_item> its(values_list);
List_item *values;
DBUG_ENTER("mysql_test_insert");
if (insert_precheck(thd, table_list))
goto error;
/*
open temporary memory pool for temporary data allocated by derived
tables & preparation procedure
Note that this is done without locks (should not be needed as we will not
access any data here)
If we would use locks, then we have to ensure we are not using
TL_WRITE_DELAYED as having two such locks can cause table corruption.
*/
if (open_normal_and_derived_tables(thd, table_list, 0))
goto error;
if ((values= its++))
{
uint value_count;
ulong counter= 0;
Item *unused_conds= 0;
if (table_list->table)
{
// don't allocate insert_values
table_list->table->insert_values=(byte *)1;
}
if (mysql_prepare_insert(thd, table_list, table_list->table,
fields, values, update_fields, update_values,
duplic, &unused_conds, FALSE))
goto error;
value_count= values->elements;
its.rewind();
if (table_list->lock_type == TL_WRITE_DELAYED &&
!(table_list->table->file->ha_table_flags() & HA_CAN_INSERT_DELAYED))
{
my_error(ER_ILLEGAL_HA, MYF(0), (table_list->view ?
table_list->view_name.str :
table_list->table_name));
goto error;
}
while ((values= its++))
{
counter++;
if (values->elements != value_count)
{
my_error(ER_WRONG_VALUE_COUNT_ON_ROW, MYF(0), counter);
goto error;
}
if (setup_fields(thd, 0, *values, MARK_COLUMNS_NONE, 0, 0))
goto error;
}
}
DBUG_RETURN(FALSE);
error:
/* insert_values is cleared in open_table */
DBUG_RETURN(TRUE);
}
/*
Validate UPDATE statement
SYNOPSIS
mysql_test_update()
stmt prepared statement
tables list of tables used in this query
RETURN VALUE
0 success
1 error, error message is set in THD
2 convert to multi_update
*/
static int mysql_test_update(Prepared_statement *stmt,
TABLE_LIST *table_list)
{
int res;
THD *thd= stmt->thd;
uint table_count= 0;
SELECT_LEX *select= &stmt->lex->select_lex;
#ifndef NO_EMBEDDED_ACCESS_CHECKS
uint want_privilege;
#endif
bool need_reopen;
DBUG_ENTER("mysql_test_update");
if (update_precheck(thd, table_list))
goto error;
for ( ; ; )
{
if (open_tables(thd, &table_list, &table_count, 0))
goto error;
if (table_list->multitable_view)
{
DBUG_ASSERT(table_list->view != 0);
DBUG_PRINT("info", ("Switch to multi-update"));
/* pass counter value */
thd->lex->table_count= table_count;
/* convert to multiupdate */
DBUG_RETURN(2);
}
if (!lock_tables(thd, table_list, table_count, &need_reopen))
break;
if (!need_reopen)
goto error;
close_tables_for_reopen(thd, &table_list);
}
/*
thd->fill_derived_tables() is false here for sure (because it is
preparation of PS, so we even do not check it).
*/
if (mysql_handle_derived(thd->lex, &mysql_derived_prepare))
goto error;
#ifndef NO_EMBEDDED_ACCESS_CHECKS
/* TABLE_LIST contain right privilages request */
want_privilege= table_list->grant.want_privilege;
#endif
if (mysql_prepare_update(thd, table_list, &select->where,
select->order_list.elements,
(ORDER *) select->order_list.first))
goto error;
#ifndef NO_EMBEDDED_ACCESS_CHECKS
table_list->grant.want_privilege= want_privilege;
table_list->table->grant.want_privilege= want_privilege;
table_list->register_want_access(want_privilege);
#endif
thd->lex->select_lex.no_wrap_view_item= TRUE;
res= setup_fields(thd, 0, select->item_list, MARK_COLUMNS_READ, 0, 0);
thd->lex->select_lex.no_wrap_view_item= FALSE;
if (res)
goto error;
#ifndef NO_EMBEDDED_ACCESS_CHECKS
/* Check values */
table_list->grant.want_privilege=
table_list->table->grant.want_privilege=
(SELECT_ACL & ~table_list->table->grant.privilege);
table_list->register_want_access(SELECT_ACL);
#endif
if (setup_fields(thd, 0, stmt->lex->value_list, MARK_COLUMNS_NONE, 0, 0))
goto error;
/* TODO: here we should send types of placeholders to the client. */
DBUG_RETURN(0);
error:
DBUG_RETURN(1);
}
/*
Validate DELETE statement.
SYNOPSIS
mysql_test_delete()
stmt prepared statement
tables list of tables used in this query
RETURN VALUE
FALSE success
TRUE error, error message is set in THD
*/
static bool mysql_test_delete(Prepared_statement *stmt,
TABLE_LIST *table_list)
{
THD *thd= stmt->thd;
LEX *lex= stmt->lex;
DBUG_ENTER("mysql_test_delete");
if (delete_precheck(thd, table_list) ||
open_and_lock_tables(thd, table_list))
goto error;
if (!table_list->table)
{
my_error(ER_VIEW_DELETE_MERGE_VIEW, MYF(0),
table_list->view_db.str, table_list->view_name.str);
goto error;
}
DBUG_RETURN(mysql_prepare_delete(thd, table_list, &lex->select_lex.where));
error:
DBUG_RETURN(TRUE);
}
/*
Validate SELECT statement.
SYNOPSIS
mysql_test_select()
stmt prepared statement
tables list of tables used in the query
DESCRIPTION
In case of success, if this query is not EXPLAIN, send column list info
back to the client.
RETURN VALUE
0 success
1 error, error message is set in THD
2 success, and statement metadata has been sent
*/
static int mysql_test_select(Prepared_statement *stmt,
TABLE_LIST *tables, bool text_protocol)
{
THD *thd= stmt->thd;
LEX *lex= stmt->lex;
SELECT_LEX_UNIT *unit= &lex->unit;
DBUG_ENTER("mysql_test_select");
lex->select_lex.context.resolve_in_select_list= TRUE;
#ifndef NO_EMBEDDED_ACCESS_CHECKS
ulong privilege= lex->exchange ? SELECT_ACL | FILE_ACL : SELECT_ACL;
if (tables)
{
if (check_table_access(thd, privilege, tables,0))
goto error;
}
else if (check_access(thd, privilege, any_db,0,0,0,0))
goto error;
#endif
if (!lex->result && !(lex->result= new (stmt->mem_root) select_send))
{
my_error(ER_OUTOFMEMORY, MYF(0), sizeof(select_send));
goto error;
}
if (open_and_lock_tables(thd, tables))
goto error;
thd->used_tables= 0; // Updated by setup_fields
/*
JOIN::prepare calls
It is not SELECT COMMAND for sure, so setup_tables will be called as
usual, and we pass 0 as setup_tables_done_option
*/
if (unit->prepare(thd, 0, 0))
goto error;
if (!lex->describe && !text_protocol)
{
/* Make copy of item list, as change_columns may change it */
List<Item> fields(lex->select_lex.item_list);
/* Change columns if a procedure like analyse() */
if (unit->last_procedure && unit->last_procedure->change_columns(fields))
goto error;
/*
We can use lex->result as it should've been prepared in
unit->prepare call above.
*/
if (send_prep_stmt(stmt, lex->result->field_count(fields)) ||
lex->result->send_fields(fields, Protocol::SEND_EOF) ||
thd->protocol->flush())
goto error;
DBUG_RETURN(2);
}
DBUG_RETURN(0);
error:
DBUG_RETURN(1);
}
/*
Validate and prepare for execution DO statement expressions.
SYNOPSIS
mysql_test_do_fields()
stmt prepared statement
tables list of tables used in this query
values list of expressions
RETURN VALUE
FALSE success
TRUE error, error message is set in THD
*/
static bool mysql_test_do_fields(Prepared_statement *stmt,
TABLE_LIST *tables,
List<Item> *values)
{
THD *thd= stmt->thd;
DBUG_ENTER("mysql_test_do_fields");
if (tables && check_table_access(thd, SELECT_ACL, tables, 0))
DBUG_RETURN(TRUE);
if (open_and_lock_tables(thd, tables))
DBUG_RETURN(TRUE);
DBUG_RETURN(setup_fields(thd, 0, *values, MARK_COLUMNS_NONE, 0, 0));
}
/*
Validate and prepare for execution SET statement expressions
SYNOPSIS
mysql_test_set_fields()
stmt prepared statement
tables list of tables used in this query
values list of expressions
RETURN VALUE
FALSE success
TRUE error, error message is set in THD
*/
static bool mysql_test_set_fields(Prepared_statement *stmt,
TABLE_LIST *tables,
List<set_var_base> *var_list)
{
DBUG_ENTER("mysql_test_set_fields");
List_iterator_fast<set_var_base> it(*var_list);
THD *thd= stmt->thd;
set_var_base *var;
if (tables && check_table_access(thd, SELECT_ACL, tables, 0) ||
open_and_lock_tables(thd, tables))
goto error;
while ((var= it++))
{
if (var->light_check(thd))
goto error;
}
DBUG_RETURN(FALSE);
error:
DBUG_RETURN(TRUE);
}
/*
Check internal SELECT of the prepared command
SYNOPSIS
select_like_stmt_test()
stmt prepared statement
specific_prepare function of command specific prepare
setup_tables_done_option options to be passed to LEX::unit.prepare()
NOTE
This function won't directly open tables used in select. They should
be opened either by calling function (and in this case you probably
should use select_like_stmt_test_with_open_n_lock()) or by
"specific_prepare" call (like this happens in case of multi-update).
RETURN VALUE
FALSE success
TRUE error, error message is set in THD
*/
static bool select_like_stmt_test(Prepared_statement *stmt,
bool (*specific_prepare)(THD *thd),
ulong setup_tables_done_option)
{
DBUG_ENTER("select_like_stmt_test");
THD *thd= stmt->thd;
LEX *lex= stmt->lex;
lex->select_lex.context.resolve_in_select_list= TRUE;
if (specific_prepare && (*specific_prepare)(thd))
DBUG_RETURN(TRUE);
thd->used_tables= 0; // Updated by setup_fields
/* Calls JOIN::prepare */
DBUG_RETURN(lex->unit.prepare(thd, 0, setup_tables_done_option));
}
/*
Check internal SELECT of the prepared command (with opening and
locking of used tables).
SYNOPSIS
select_like_stmt_test_with_open_n_lock()
stmt prepared statement
tables list of tables to be opened and locked
before calling specific_prepare function
specific_prepare function of command specific prepare
setup_tables_done_option options to be passed to LEX::unit.prepare()
RETURN VALUE
FALSE success
TRUE error
*/
static bool
select_like_stmt_test_with_open_n_lock(Prepared_statement *stmt,
TABLE_LIST *tables,
bool (*specific_prepare)(THD *thd),
ulong setup_tables_done_option)
{
DBUG_ENTER("select_like_stmt_test_with_open_n_lock");
/*
We should not call LEX::unit.cleanup() after this open_and_lock_tables()
call because we don't allow prepared EXPLAIN yet so derived tables will
clean up after themself.
*/
if (open_and_lock_tables(stmt->thd, tables))
DBUG_RETURN(TRUE);
DBUG_RETURN(select_like_stmt_test(stmt, specific_prepare,
setup_tables_done_option));
}
/*
Validate and prepare for execution CREATE TABLE statement
SYNOPSIS
mysql_test_create_table()
stmt prepared statement
tables list of tables used in this query
RETURN VALUE
FALSE success
TRUE error, error message is set in THD
*/
static bool mysql_test_create_table(Prepared_statement *stmt)
{
DBUG_ENTER("mysql_test_create_table");
THD *thd= stmt->thd;
LEX *lex= stmt->lex;
SELECT_LEX *select_lex= &lex->select_lex;
bool res= FALSE;
/* Skip first table, which is the table we are creating */
bool link_to_local;
TABLE_LIST *create_table= lex->unlink_first_table(&link_to_local);
TABLE_LIST *tables= lex->query_tables;
if (create_table_precheck(thd, tables, create_table))
DBUG_RETURN(TRUE);
if (select_lex->item_list.elements)
{
select_lex->context.resolve_in_select_list= TRUE;
res= select_like_stmt_test_with_open_n_lock(stmt, tables, 0, 0);
}
/* put tables back for PS rexecuting */
lex->link_first_table_back(create_table, link_to_local);
DBUG_RETURN(res);
}
/*
Validate and prepare for execution a multi update statement.
SYNOPSIS
mysql_test_multiupdate()
stmt prepared statement
tables list of tables used in this query
converted converted to multi-update from usual update
RETURN VALUE
FALSE success
TRUE error, error message is set in THD
*/
static bool mysql_test_multiupdate(Prepared_statement *stmt,
TABLE_LIST *tables,
bool converted)
{
/* if we switched from normal update, rights are checked */
if (!converted && multi_update_precheck(stmt->thd, tables))
return TRUE;
return select_like_stmt_test(stmt, &mysql_multi_update_prepare,
OPTION_SETUP_TABLES_DONE);
}
/*
Validate and prepare for execution a multi delete statement.
SYNOPSIS
mysql_test_multidelete()
stmt prepared statement
tables list of tables used in this query
RETURN VALUE
FALSE success
TRUE error, error message in THD is set.
*/
static bool mysql_test_multidelete(Prepared_statement *stmt,
TABLE_LIST *tables)
{
stmt->thd->lex->current_select= &stmt->thd->lex->select_lex;
if (add_item_to_list(stmt->thd, new Item_null()))
{
my_error(ER_OUTOFMEMORY, MYF(0), 0);
goto error;
}
if (multi_delete_precheck(stmt->thd, tables) ||
select_like_stmt_test_with_open_n_lock(stmt, tables,
&mysql_multi_delete_prepare,
OPTION_SETUP_TABLES_DONE))
goto error;
if (!tables->table)
{
my_error(ER_VIEW_DELETE_MERGE_VIEW, MYF(0),
tables->view_db.str, tables->view_name.str);
goto error;
}
return FALSE;
error:
return TRUE;
}
/*
Wrapper for mysql_insert_select_prepare, to make change of local tables
after open_and_lock_tables() call.
SYNOPSIS
mysql_insert_select_prepare_tester()
thd thread handle
NOTE
We need to remove the first local table after open_and_lock_tables,
because mysql_handle_derived uses local tables lists.
*/
static bool mysql_insert_select_prepare_tester(THD *thd)
{
TABLE_LIST *first;
bool res;
SELECT_LEX *first_select= &thd->lex->select_lex;
/* Skip first table, which is the table we are inserting in */
first_select->table_list.first= (byte*)(first=
((TABLE_LIST*)first_select->
table_list.first)->next_local);
res= mysql_insert_select_prepare(thd);
/*
insert/replace from SELECT give its SELECT_LEX for SELECT,
and item_list belong to SELECT
*/
thd->lex->select_lex.context.resolve_in_select_list= TRUE;
thd->lex->select_lex.context.table_list= first;
return res;
}
/*
Validate and prepare for execution INSERT ... SELECT statement.
SYNOPSIS
mysql_test_insert_select()
stmt prepared statement
tables list of tables used in this query
RETURN VALUE
FALSE success
TRUE error, error message is set in THD
*/
static bool mysql_test_insert_select(Prepared_statement *stmt,
TABLE_LIST *tables)
{
int res;
LEX *lex= stmt->lex;
TABLE_LIST *first_local_table;
if (tables->table)
{
// don't allocate insert_values
tables->table->insert_values=(byte *)1;
}
if (insert_precheck(stmt->thd, tables))
return 1;
/* store it, because mysql_insert_select_prepare_tester change it */
first_local_table= (TABLE_LIST *)lex->select_lex.table_list.first;
DBUG_ASSERT(first_local_table != 0);
res=
select_like_stmt_test_with_open_n_lock(stmt, tables,
&mysql_insert_select_prepare_tester,
OPTION_SETUP_TABLES_DONE);
/* revert changes made by mysql_insert_select_prepare_tester */
lex->select_lex.table_list.first= (byte*) first_local_table;
return res;
}
/*
Perform semantic analysis of the parsed tree and send a response packet
to the client.
SYNOPSIS
check_prepared_statement()
stmt prepared statement
DESCRIPTION
This function
- opens all tables and checks access rights
- validates semantics of statement columns and SQL functions
by calling fix_fields.
RETURN VALUE
FALSE success, statement metadata is sent to client
TRUE error, error message is set in THD (but not sent)
*/
static bool check_prepared_statement(Prepared_statement *stmt,
bool text_protocol)
{
THD *thd= stmt->thd;
LEX *lex= stmt->lex;
SELECT_LEX *select_lex= &lex->select_lex;
TABLE_LIST *tables;
enum enum_sql_command sql_command= lex->sql_command;
int res= 0;
DBUG_ENTER("check_prepared_statement");
DBUG_PRINT("enter",("command: %d, param_count: %u",
sql_command, stmt->param_count));
lex->first_lists_tables_same();
tables= lex->query_tables;
/* set context for commands which do not use setup_tables */
lex->select_lex.context.resolve_in_table_list_only(select_lex->
get_table_list());
switch (sql_command) {
case SQLCOM_REPLACE:
case SQLCOM_INSERT:
res= mysql_test_insert(stmt, tables, lex->field_list,
lex->many_values,
select_lex->item_list, lex->value_list,
lex->duplicates);
break;
case SQLCOM_UPDATE:
res= mysql_test_update(stmt, tables);
/* mysql_test_update returns 2 if we need to switch to multi-update */
if (res != 2)
break;
case SQLCOM_UPDATE_MULTI:
res= mysql_test_multiupdate(stmt, tables, res == 2);
break;
case SQLCOM_DELETE:
res= mysql_test_delete(stmt, tables);
break;
case SQLCOM_SELECT:
res= mysql_test_select(stmt, tables, text_protocol);
if (res == 2)
{
/* Statement and field info has already been sent */
DBUG_RETURN(FALSE);
}
break;
case SQLCOM_CREATE_TABLE:
res= mysql_test_create_table(stmt);
break;
case SQLCOM_DO:
res= mysql_test_do_fields(stmt, tables, lex->insert_list);
break;
case SQLCOM_SET_OPTION:
res= mysql_test_set_fields(stmt, tables, &lex->var_list);
break;
case SQLCOM_DELETE_MULTI:
res= mysql_test_multidelete(stmt, tables);
break;
case SQLCOM_INSERT_SELECT:
case SQLCOM_REPLACE_SELECT:
res= mysql_test_insert_select(stmt, tables);
break;
/*
Note that we don't need to have cases in this list if they are
marked with CF_STATUS_COMMAND in sql_command_flags
*/
case SQLCOM_SHOW_PROCESSLIST:
case SQLCOM_SHOW_STORAGE_ENGINES:
case SQLCOM_SHOW_PRIVILEGES:
case SQLCOM_SHOW_COLUMN_TYPES:
case SQLCOM_SHOW_ENGINE_LOGS:
case SQLCOM_SHOW_ENGINE_STATUS:
case SQLCOM_SHOW_ENGINE_MUTEX:
case SQLCOM_SHOW_CREATE_DB:
case SQLCOM_SHOW_GRANTS:
case SQLCOM_SHOW_BINLOG_EVENTS:
case SQLCOM_SHOW_MASTER_STAT:
case SQLCOM_SHOW_SLAVE_STAT:
case SQLCOM_SHOW_CREATE_PROC:
case SQLCOM_SHOW_CREATE_FUNC:
case SQLCOM_SHOW_CREATE_EVENT:
case SQLCOM_SHOW_CREATE:
case SQLCOM_SHOW_PROC_CODE:
case SQLCOM_SHOW_FUNC_CODE:
case SQLCOM_SHOW_AUTHORS:
case SQLCOM_SHOW_CONTRIBUTORS:
case SQLCOM_SHOW_WARNS:
case SQLCOM_SHOW_ERRORS:
case SQLCOM_SHOW_BINLOGS:
case SQLCOM_DROP_TABLE:
case SQLCOM_RENAME_TABLE:
case SQLCOM_ALTER_TABLE:
case SQLCOM_COMMIT:
case SQLCOM_CREATE_INDEX:
case SQLCOM_DROP_INDEX:
case SQLCOM_ROLLBACK:
case SQLCOM_TRUNCATE:
case SQLCOM_CALL:
case SQLCOM_CREATE_VIEW:
case SQLCOM_DROP_VIEW:
case SQLCOM_REPAIR:
case SQLCOM_ANALYZE:
case SQLCOM_OPTIMIZE:
case SQLCOM_CHANGE_MASTER:
case SQLCOM_RESET:
case SQLCOM_FLUSH:
case SQLCOM_SLAVE_START:
case SQLCOM_SLAVE_STOP:
case SQLCOM_INSTALL_PLUGIN:
case SQLCOM_UNINSTALL_PLUGIN:
case SQLCOM_CREATE_DB:
case SQLCOM_DROP_DB:
case SQLCOM_RENAME_DB:
case SQLCOM_CHECKSUM:
case SQLCOM_CREATE_USER:
case SQLCOM_RENAME_USER:
case SQLCOM_DROP_USER:
case SQLCOM_ASSIGN_TO_KEYCACHE:
case SQLCOM_PRELOAD_KEYS:
case SQLCOM_GRANT:
case SQLCOM_REVOKE:
case SQLCOM_KILL:
break;
default:
/*
Trivial check of all status commands. This is easier than having
things in the above case list, as it's less chance for mistakes.
*/
if (!(sql_command_flags[sql_command] & CF_STATUS_COMMAND))
{
/* All other statements are not supported yet. */
my_message(ER_UNSUPPORTED_PS, ER(ER_UNSUPPORTED_PS), MYF(0));
goto error;
}
break;
}
if (res == 0)
DBUG_RETURN(text_protocol? FALSE : (send_prep_stmt(stmt, 0) ||
thd->protocol->flush()));
error:
DBUG_RETURN(TRUE);
}
/*
Initialize array of parameters in statement from LEX.
(We need to have quick access to items by number in mysql_stmt_get_longdata).
This is to avoid using malloc/realloc in the parser.
*/
static bool init_param_array(Prepared_statement *stmt)
{
LEX *lex= stmt->lex;
if ((stmt->param_count= lex->param_list.elements))
{
if (stmt->param_count > (uint) UINT_MAX16)
{
/* Error code to be defined in 5.0 */
my_message(ER_PS_MANY_PARAM, ER(ER_PS_MANY_PARAM), MYF(0));
return TRUE;
}
Item_param **to;
List_iterator<Item_param> param_iterator(lex->param_list);
/* Use thd->mem_root as it points at statement mem_root */
stmt->param_array= (Item_param **)
alloc_root(stmt->thd->mem_root,
sizeof(Item_param*) * stmt->param_count);
if (!stmt->param_array)
return TRUE;
for (to= stmt->param_array;
to < stmt->param_array + stmt->param_count;
++to)
{
*to= param_iterator++;
}
}
return FALSE;
}
/*
COM_STMT_PREPARE handler.
SYNOPSIS
mysql_stmt_prepare()
packet query to be prepared
packet_length query string length, including ignored
trailing NULL or quote char.
DESCRIPTION
Given a query string with parameter markers, create a prepared
statement from it and send PS info back to the client.
NOTES
This function parses the query and sends the total number of parameters
and resultset metadata information back to client (if any), without
executing the query i.e. without any log/disk writes. This allows the
queries to be re-executed without re-parsing during execute.
If parameter markers are found in the query, then store the information
using Item_param along with maintaining a list in lex->param_array, so
that a fast and direct retrieval can be made without going through all
field items.
RETURN VALUE
none: in case of success a new statement id and metadata is sent
to the client, otherwise an error message is set in THD.
*/
void mysql_stmt_prepare(THD *thd, const char *packet, uint packet_length)
{
Prepared_statement *stmt;
bool error;
DBUG_ENTER("mysql_stmt_prepare");
DBUG_PRINT("prep_query", ("%s", packet));
/* First of all clear possible warnings from the previous command */
mysql_reset_thd_for_next_command(thd);
if (! (stmt= new Prepared_statement(thd, &thd->protocol_prep)))
DBUG_VOID_RETURN; /* out of memory: error is set in Sql_alloc */
if (thd->stmt_map.insert(thd, stmt))
{
/*
The error is set in the insert. The statement itself
will be also deleted there (this is how the hash works).
*/
DBUG_VOID_RETURN;
}
/* Reset warnings from previous command */
mysql_reset_errors(thd, 0);
sp_cache_flush_obsolete(&thd->sp_proc_cache);
sp_cache_flush_obsolete(&thd->sp_func_cache);
if (!(specialflag & SPECIAL_NO_PRIOR))
my_pthread_setprio(pthread_self(),QUERY_PRIOR);
error= stmt->prepare(packet, packet_length);
if (!(specialflag & SPECIAL_NO_PRIOR))
my_pthread_setprio(pthread_self(),WAIT_PRIOR);
if (error)
{
/* Statement map deletes statement on erase */
thd->stmt_map.erase(stmt);
}
else
{
const char *format= "[%lu] %.*b";
general_log_print(thd, COM_STMT_PREPARE, format, stmt->id,
stmt->query_length, stmt->query);
}
/* check_prepared_statemnt sends the metadata packet in case of success */
DBUG_VOID_RETURN;
}
/*
SYNOPSIS
get_dynamic_sql_string()
lex in main lex
query_len out length of the SQL statement (is set only
in case of success)
DESCRIPTION
Get an SQL statement text from a user variable or from plain
text. If the statement is plain text, just assign the
pointers, otherwise allocate memory in thd->mem_root and copy
the contents of the variable, possibly with character
set conversion.
RETURN VALUE
non-zero success, 0 in case of error (out of memory)
*/
static const char *get_dynamic_sql_string(LEX *lex, uint *query_len)
{
THD *thd= lex->thd;
char *query_str= 0;
if (lex->prepared_stmt_code_is_varref)
{
/* This is PREPARE stmt FROM or EXECUTE IMMEDIATE @var. */
String str;
CHARSET_INFO *to_cs= thd->variables.collation_connection;
bool needs_conversion;
user_var_entry *entry;
String *var_value= &str;
uint32 unused, len;
/*
Convert @var contents to string in connection character set. Although
it is known that int/real/NULL value cannot be a valid query we still
convert it for error messages to be uniform.
*/
if ((entry=
(user_var_entry*)hash_search(&thd->user_vars,
(byte*)lex->prepared_stmt_code.str,
lex->prepared_stmt_code.length))
&& entry->value)
{
my_bool is_var_null;
var_value= entry->val_str(&is_var_null, &str, NOT_FIXED_DEC);
/*
NULL value of variable checked early as entry->value so here
we can't get NULL in normal conditions
*/
DBUG_ASSERT(!is_var_null);
if (!var_value)
goto end;
}
else
{
/*
variable absent or equal to NULL, so we need to set variable to
something reasonable to get a readable error message during parsing
*/
str.set(STRING_WITH_LEN("NULL"), &my_charset_latin1);
}
needs_conversion= String::needs_conversion(var_value->length(),
var_value->charset(), to_cs,
&unused);
len= (needs_conversion ? var_value->length() * to_cs->mbmaxlen :
var_value->length());
if (!(query_str= alloc_root(thd->mem_root, len+1)))
goto end;
if (needs_conversion)
{
uint dummy_errors;
len= copy_and_convert(query_str, len, to_cs, var_value->ptr(),
var_value->length(), var_value->charset(),
&dummy_errors);
}
else
memcpy(query_str, var_value->ptr(), var_value->length());
query_str[len]= '\0'; // Safety (mostly for debug)
*query_len= len;
}
else
{
query_str= lex->prepared_stmt_code.str;
*query_len= lex->prepared_stmt_code.length;
}
end:
return query_str;
}
/* Init PS/SP specific parse tree members. */
static void init_stmt_after_parse(LEX *lex)
{
SELECT_LEX *sl= lex->all_selects_list;
/*
Switch off a temporary flag that prevents evaluation of
subqueries in statement prepare.
*/
for (; sl; sl= sl->next_select_in_list())
sl->uncacheable&= ~UNCACHEABLE_PREPARE;
}
/*
SQLCOM_PREPARE implementation.
SYNOPSIS
mysql_sql_stmt_prepare()
thd thread handle
DESCRIPTION
Prepare an SQL prepared statement. This is called from
mysql_execute_command and should therefore behave like an
ordinary query (e.g. should not reset any global THD data).
RETURN VALUE
none: in case of success, OK packet is sent to the client,
otherwise an error message is set in THD
*/
void mysql_sql_stmt_prepare(THD *thd)
{
LEX *lex= thd->lex;
LEX_STRING *name= &lex->prepared_stmt_name;
Prepared_statement *stmt;
const char *query;
uint query_len;
DBUG_ENTER("mysql_sql_stmt_prepare");
DBUG_ASSERT(thd->protocol == &thd->protocol_simple);
if ((stmt= (Prepared_statement*) thd->stmt_map.find_by_name(name)))
{
/*
If there is a statement with the same name, remove it. It is ok to
remove old and fail to insert a new one at the same time.
*/
if (stmt->deallocate())
DBUG_VOID_RETURN;
}
if (! (query= get_dynamic_sql_string(lex, &query_len)) ||
! (stmt= new Prepared_statement(thd, &thd->protocol_simple)))
{
DBUG_VOID_RETURN; /* out of memory */
}
/* Set the name first, insert should know that this statement has a name */
if (stmt->set_name(name))
{
delete stmt;
DBUG_VOID_RETURN;
}
if (thd->stmt_map.insert(thd, stmt))
{
/* The statement is deleted and an error is set if insert fails */
DBUG_VOID_RETURN;
}
if (stmt->prepare(query, query_len+1))
{
/* Statement map deletes the statement on erase */
thd->stmt_map.erase(stmt);
}
else
send_ok(thd, 0L, 0L, "Statement prepared");
DBUG_VOID_RETURN;
}
/* Reinit prepared statement/stored procedure before execution */
void reinit_stmt_before_use(THD *thd, LEX *lex)
{
SELECT_LEX *sl= lex->all_selects_list;
DBUG_ENTER("reinit_stmt_before_use");
/*
We have to update "thd" pointer in LEX, all its units and in LEX::result,
since statements which belong to trigger body are associated with TABLE
object and because of this can be used in different threads.
*/
lex->thd= thd;
if (lex->empty_field_list_on_rset)
{
lex->empty_field_list_on_rset= 0;
lex->field_list.empty();
}
for (; sl; sl= sl->next_select_in_list())
{
if (!sl->first_execution)
{
/* remove option which was put by mysql_explain_union() */
sl->options&= ~SELECT_DESCRIBE;
/* see unique_table() */
sl->exclude_from_table_unique_test= FALSE;
/*
Copy WHERE, HAVING clause pointers to avoid damaging them
by optimisation
*/
if (sl->prep_where)
{
sl->where= sl->prep_where->copy_andor_structure(thd);
sl->where->cleanup();
}
if (sl->prep_having)
{
sl->having= sl->prep_having->copy_andor_structure(thd);
sl->having->cleanup();
}
DBUG_ASSERT(sl->join == 0);
ORDER *order;
/* Fix GROUP list */
for (order= (ORDER *)sl->group_list.first; order; order= order->next)
order->item= &order->item_ptr;
/* Fix ORDER list */
for (order= (ORDER *)sl->order_list.first; order; order= order->next)
order->item= &order->item_ptr;
}
{
SELECT_LEX_UNIT *unit= sl->master_unit();
unit->unclean();
unit->types.empty();
/* for derived tables & PS (which can't be reset by Item_subquery) */
unit->reinit_exec_mechanism();
unit->set_thd(thd);
}
}
/*
TODO: When the new table structure is ready, then have a status bit
to indicate the table is altered, and re-do the setup_*
and open the tables back.
*/
/*
NOTE: We should reset whole table list here including all tables added
by prelocking algorithm (it is not a problem for substatements since
they have their own table list).
*/
for (TABLE_LIST *tables= lex->query_tables;
tables;
tables= tables->next_global)
{
tables->reinit_before_use(thd);
}
/*
Cleanup of the special case of DELETE t1, t2 FROM t1, t2, t3 ...
(multi-delete). We do a full clean up, although at the moment all we
need to clean in the tables of MULTI-DELETE list is 'table' member.
*/
for (TABLE_LIST *tables= (TABLE_LIST*) lex->auxiliary_table_list.first;
tables;
tables= tables->next_global)
{
tables->reinit_before_use(thd);
}
lex->current_select= &lex->select_lex;
/* restore original list used in INSERT ... SELECT */
if (lex->leaf_tables_insert)
lex->select_lex.leaf_tables= lex->leaf_tables_insert;
if (lex->result)
{
lex->result->cleanup();
lex->result->set_thd(thd);
}
lex->allow_sum_func= 0;
lex->in_sum_func= NULL;
DBUG_VOID_RETURN;
}
/*
Clears parameters from data left from previous execution or long data
SYNOPSIS
reset_stmt_params()
stmt prepared statement for which parameters should
be reset
*/
static void reset_stmt_params(Prepared_statement *stmt)
{
Item_param **item= stmt->param_array;
Item_param **end= item + stmt->param_count;
for (;item < end ; ++item)
(**item).reset();
}
/*
COM_STMT_EXECUTE handler: execute a previously prepared statement.
SYNOPSIS
mysql_stmt_execute()
thd current thread
packet parameter types and data, if any
packet_length packet length, including the terminator character.
DESCRIPTION
If there are any parameters, then replace parameter markers with the
data supplied from the client, and then execute the statement.
This function uses binary protocol to send a possible result set
to the client.
RETURN VALUE
none: in case of success OK packet or a result set is sent to the
client, otherwise an error message is set in THD.
*/
void mysql_stmt_execute(THD *thd, char *packet_arg, uint packet_length)
{
uchar *packet= (uchar*)packet_arg; // GCC 4.0.1 workaround
ulong stmt_id= uint4korr(packet);
ulong flags= (ulong) ((uchar) packet[4]);
/* Query text for binary, general or slow log, if any of them is open */
String expanded_query;
#ifndef EMBEDDED_LIBRARY
uchar *packet_end= (uchar *) packet + packet_length - 1;
#endif
Prepared_statement *stmt;
bool error;
DBUG_ENTER("mysql_stmt_execute");
packet+= 9; /* stmt_id + 5 bytes of flags */
/* First of all clear possible warnings from the previous command */
mysql_reset_thd_for_next_command(thd);
if (!(stmt= find_prepared_statement(thd, stmt_id, "mysql_stmt_execute")))
DBUG_VOID_RETURN;
DBUG_PRINT("exec_query", ("%s", stmt->query));
DBUG_PRINT("info",("stmt: 0x%lx", (long) stmt));
sp_cache_flush_obsolete(&thd->sp_proc_cache);
sp_cache_flush_obsolete(&thd->sp_func_cache);
#ifndef EMBEDDED_LIBRARY
if (stmt->param_count)
{
uchar *null_array= (uchar *) packet;
if (setup_conversion_functions(stmt, (uchar **) &packet, packet_end) ||
stmt->set_params(stmt, null_array, (uchar *) packet, packet_end,
&expanded_query))
goto set_params_data_err;
}
#else
/*
In embedded library we re-install conversion routines each time
we set params, and also we don't need to parse packet.
So we do it in one function.
*/
if (stmt->param_count && stmt->set_params_data(stmt, &expanded_query))
goto set_params_data_err;
#endif
if (!(specialflag & SPECIAL_NO_PRIOR))
my_pthread_setprio(pthread_self(),QUERY_PRIOR);
/*
If the free_list is not empty, we'll wrongly free some externally
allocated items when cleaning up after validation of the prepared
statement.
*/
DBUG_ASSERT(thd->free_list == NULL);
error= stmt->execute(&expanded_query,
test(flags & (ulong) CURSOR_TYPE_READ_ONLY));
if (!(specialflag & SPECIAL_NO_PRIOR))
my_pthread_setprio(pthread_self(), WAIT_PRIOR);
if (error == 0)
{
const char *format= "[%lu] %.*b";
general_log_print(thd, COM_STMT_EXECUTE, format, stmt->id,
thd->query_length, thd->query);
}
DBUG_VOID_RETURN;
set_params_data_err:
my_error(ER_WRONG_ARGUMENTS, MYF(0), "mysql_stmt_execute");
reset_stmt_params(stmt);
DBUG_VOID_RETURN;
}
/*
SQLCOM_EXECUTE implementation.
SYNOPSIS
mysql_sql_stmt_execute()
thd thread handle
DESCRIPTION
Execute prepared statement using parameter values from
lex->prepared_stmt_params and send result to the client using
text protocol. This is called from mysql_execute_command and
therefore should behave like an ordinary query (e.g. not change
global THD data, such as warning count, server status, etc).
This function uses text protocol to send a possible result set.
RETURN
none: in case of success, OK (or result set) packet is sent to the
client, otherwise an error is set in THD
*/
void mysql_sql_stmt_execute(THD *thd)
{
LEX *lex= thd->lex;
Prepared_statement *stmt;
LEX_STRING *name= &lex->prepared_stmt_name;
/* Query text for binary, general or slow log, if any of them is open */
String expanded_query;
DBUG_ENTER("mysql_sql_stmt_execute");
DBUG_PRINT("info", ("EXECUTE: %.*s\n", name->length, name->str));
if (!(stmt= (Prepared_statement*) thd->stmt_map.find_by_name(name)))
{
my_error(ER_UNKNOWN_STMT_HANDLER, MYF(0),
name->length, name->str, "EXECUTE");
DBUG_VOID_RETURN;
}
if (stmt->param_count != lex->prepared_stmt_params.elements)
{
my_error(ER_WRONG_ARGUMENTS, MYF(0), "EXECUTE");
DBUG_VOID_RETURN;
}
DBUG_PRINT("info",("stmt: 0x%lx", (long) stmt));
/*
If the free_list is not empty, we'll wrongly free some externally
allocated items when cleaning up after validation of the prepared
statement.
*/
DBUG_ASSERT(thd->free_list == NULL);
if (stmt->set_params_from_vars(stmt, lex->prepared_stmt_params,
&expanded_query))
goto set_params_data_err;
(void) stmt->execute(&expanded_query, FALSE);
DBUG_VOID_RETURN;
set_params_data_err:
my_error(ER_WRONG_ARGUMENTS, MYF(0), "EXECUTE");
reset_stmt_params(stmt);
DBUG_VOID_RETURN;
}
/*
COM_STMT_FETCH handler: fetches requested amount of rows from cursor
SYNOPSIS
mysql_stmt_fetch()
thd Thread handle
packet Packet from client (with stmt_id & num_rows)
packet_length Length of packet
*/
void mysql_stmt_fetch(THD *thd, char *packet, uint packet_length)
{
/* assume there is always place for 8-16 bytes */
ulong stmt_id= uint4korr(packet);
ulong num_rows= uint4korr(packet+4);
Prepared_statement *stmt;
Statement stmt_backup;
Server_side_cursor *cursor;
DBUG_ENTER("mysql_stmt_fetch");
/* First of all clear possible warnings from the previous command */
mysql_reset_thd_for_next_command(thd);
statistic_increment(thd->status_var.com_stmt_fetch, &LOCK_status);
if (!(stmt= find_prepared_statement(thd, stmt_id, "mysql_stmt_fetch")))
DBUG_VOID_RETURN;
cursor= stmt->cursor;
if (!cursor)
{
my_error(ER_STMT_HAS_NO_OPEN_CURSOR, MYF(0), stmt_id);
DBUG_VOID_RETURN;
}
thd->stmt_arena= stmt;
thd->set_n_backup_statement(stmt, &stmt_backup);
if (!(specialflag & SPECIAL_NO_PRIOR))
my_pthread_setprio(pthread_self(), QUERY_PRIOR);
cursor->fetch(num_rows);
if (!(specialflag & SPECIAL_NO_PRIOR))
my_pthread_setprio(pthread_self(), WAIT_PRIOR);
if (!cursor->is_open())
{
stmt->close_cursor();
thd->cursor= 0;
reset_stmt_params(stmt);
}
thd->restore_backup_statement(stmt, &stmt_backup);
thd->stmt_arena= thd;
DBUG_VOID_RETURN;
}
/*
Reset a prepared statement in case there was a recoverable error.
SYNOPSIS
mysql_stmt_reset()
thd Thread handle
packet Packet with stmt id
DESCRIPTION
This function resets statement to the state it was right after prepare.
It can be used to:
- clear an error happened during mysql_stmt_send_long_data
- cancel long data stream for all placeholders without
having to call mysql_stmt_execute.
- close an open cursor
Sends 'OK' packet in case of success (statement was reset)
or 'ERROR' packet (unrecoverable error/statement not found/etc).
*/
void mysql_stmt_reset(THD *thd, char *packet)
{
/* There is always space for 4 bytes in buffer */
ulong stmt_id= uint4korr(packet);
Prepared_statement *stmt;
DBUG_ENTER("mysql_stmt_reset");
/* First of all clear possible warnings from the previous command */
mysql_reset_thd_for_next_command(thd);
statistic_increment(thd->status_var.com_stmt_reset, &LOCK_status);
if (!(stmt= find_prepared_statement(thd, stmt_id, "mysql_stmt_reset")))
DBUG_VOID_RETURN;
stmt->close_cursor();
/*
Clear parameters from data which could be set by
mysql_stmt_send_long_data() call.
*/
reset_stmt_params(stmt);
stmt->state= Query_arena::PREPARED;
send_ok(thd);
DBUG_VOID_RETURN;
}
/*
Delete a prepared statement from memory.
Note: we don't send any reply to this command.
*/
void mysql_stmt_close(THD *thd, char *packet)
{
/* There is always space for 4 bytes in packet buffer */
ulong stmt_id= uint4korr(packet);
Prepared_statement *stmt;
DBUG_ENTER("mysql_stmt_close");
if (!(stmt= find_prepared_statement(thd, stmt_id, "mysql_stmt_close")))
DBUG_VOID_RETURN;
/*
The only way currently a statement can be deallocated when it's
in use is from within Dynamic SQL.
*/
DBUG_ASSERT(! (stmt->flags & (uint) Prepared_statement::IS_IN_USE));
(void) stmt->deallocate();
DBUG_VOID_RETURN;
}
/*
SQLCOM_DEALLOCATE implementation.
DESCRIPTION
Close an SQL prepared statement. As this can be called from Dynamic
SQL, we should be careful to not close a statement that is currently
being executed.
RETURN VALUE
none: OK packet is sent in case of success, otherwise an error
message is set in THD
*/
void mysql_sql_stmt_close(THD *thd)
{
Prepared_statement* stmt;
LEX_STRING *name= &thd->lex->prepared_stmt_name;
DBUG_PRINT("info", ("DEALLOCATE PREPARE: %.*s\n", name->length, name->str));
if (! (stmt= (Prepared_statement*) thd->stmt_map.find_by_name(name)))
{
my_error(ER_UNKNOWN_STMT_HANDLER, MYF(0),
name->length, name->str, "DEALLOCATE PREPARE");
return;
}
if (stmt->deallocate() == 0)
send_ok(thd);
}
/*
Handle long data in pieces from client.
SYNOPSIS
mysql_stmt_get_longdata()
thd Thread handle
packet String to append
packet_length Length of string (including end \0)
DESCRIPTION
Get a part of a long data. To make the protocol efficient, we are
not sending any return packets here. If something goes wrong, then
we will send the error on 'execute' We assume that the client takes
care of checking that all parts are sent to the server. (No checking
that we get a 'end of column' in the server is performed).
*/
void mysql_stmt_get_longdata(THD *thd, char *packet, ulong packet_length)
{
ulong stmt_id;
uint param_number;
Prepared_statement *stmt;
Item_param *param;
char *packet_end= packet + packet_length - 1;
DBUG_ENTER("mysql_stmt_get_longdata");
statistic_increment(thd->status_var.com_stmt_send_long_data, &LOCK_status);
#ifndef EMBEDDED_LIBRARY
/* Minimal size of long data packet is 6 bytes */
if (packet_length <= MYSQL_LONG_DATA_HEADER)
{
my_error(ER_WRONG_ARGUMENTS, MYF(0), "mysql_stmt_send_long_data");
DBUG_VOID_RETURN;
}
#endif
stmt_id= uint4korr(packet);
packet+= 4;
if (!(stmt=find_prepared_statement(thd, stmt_id,
"mysql_stmt_send_long_data")))
DBUG_VOID_RETURN;
param_number= uint2korr(packet);
packet+= 2;
#ifndef EMBEDDED_LIBRARY
if (param_number >= stmt->param_count)
{
/* Error will be sent in execute call */
stmt->state= Query_arena::ERROR;
stmt->last_errno= ER_WRONG_ARGUMENTS;
sprintf(stmt->last_error, ER(ER_WRONG_ARGUMENTS),
"mysql_stmt_send_long_data");
DBUG_VOID_RETURN;
}
#endif
param= stmt->param_array[param_number];
#ifndef EMBEDDED_LIBRARY
if (param->set_longdata(packet, (ulong) (packet_end - packet)))
#else
if (param->set_longdata(thd->extra_data, thd->extra_length))
#endif
{
stmt->state= Query_arena::ERROR;
stmt->last_errno= ER_OUTOFMEMORY;
sprintf(stmt->last_error, ER(ER_OUTOFMEMORY), 0);
}
DBUG_VOID_RETURN;
}
/***************************************************************************
Select_fetch_protocol_prep
****************************************************************************/
Select_fetch_protocol_prep::Select_fetch_protocol_prep(THD *thd)
:protocol(thd)
{}
bool Select_fetch_protocol_prep::send_fields(List<Item> &list, uint flags)
{
bool rc;
Protocol *save_protocol= thd->protocol;
/*
Protocol::send_fields caches the information about column types:
this information is later used to send data. Therefore, the same
dedicated Protocol object must be used for all operations with
a cursor.
*/
thd->protocol= &protocol;
rc= select_send::send_fields(list, flags);
thd->protocol= save_protocol;
return rc;
}
bool Select_fetch_protocol_prep::send_eof()
{
Protocol *save_protocol= thd->protocol;
thd->protocol= &protocol;
::send_eof(thd);
thd->protocol= save_protocol;
return FALSE;
}
bool
Select_fetch_protocol_prep::send_data(List<Item> &fields)
{
Protocol *save_protocol= thd->protocol;
bool rc;
thd->protocol= &protocol;
rc= select_send::send_data(fields);
thd->protocol= save_protocol;
return rc;
}
/***************************************************************************
Prepared_statement
****************************************************************************/
Prepared_statement::Prepared_statement(THD *thd_arg, Protocol *protocol_arg)
:Statement(INITIALIZED, ++thd_arg->statement_id_counter,
thd_arg->variables.query_alloc_block_size,
thd_arg->variables.query_prealloc_size),
thd(thd_arg),
result(thd_arg),
protocol(protocol_arg),
param_array(0),
param_count(0),
last_errno(0),
flags((uint) IS_IN_USE)
{
*last_error= '\0';
}
void Prepared_statement::setup_set_params()
{
/* Setup binary logging */
if (mysql_bin_log.is_open() && is_update_query(lex->sql_command) ||
opt_log || opt_slow_log)
{
set_params_from_vars= insert_params_from_vars_with_log;
#ifndef EMBEDDED_LIBRARY
set_params= insert_params_withlog;
#else
set_params_data= emb_insert_params_withlog;
#endif
}
else
{
set_params_from_vars= insert_params_from_vars;
#ifndef EMBEDDED_LIBRARY
set_params= insert_params;
#else
set_params_data= emb_insert_params;
#endif
}
}
/*
DESCRIPTION
Destroy this prepared statement, cleaning up all used memory
and resources. This is called from ::deallocate() to
handle COM_STMT_CLOSE and DEALLOCATE PREPARE or when
THD ends and all prepared statements are freed.
*/
Prepared_statement::~Prepared_statement()
{
DBUG_ENTER("Prepared_statement::~Prepared_statement");
DBUG_PRINT("enter",("stmt: 0x%lx cursor: 0x%lx",
(long) this, (long) cursor));
delete cursor;
/*
We have to call free on the items even if cleanup is called as some items,
like Item_param, don't free everything until free_items()
*/
free_items();
delete lex->result;
DBUG_VOID_RETURN;
}
Query_arena::Type Prepared_statement::type() const
{
return PREPARED_STATEMENT;
}
void Prepared_statement::cleanup_stmt()
{
DBUG_ENTER("Prepared_statement::cleanup_stmt");
DBUG_PRINT("enter",("stmt: 0x%lx", (long) this));
/* The order is important */
lex->unit.cleanup();
cleanup_items(free_list);
thd->cleanup_after_query();
close_thread_tables(thd);
thd->rollback_item_tree_changes();
DBUG_VOID_RETURN;
}
bool Prepared_statement::set_name(LEX_STRING *name_arg)
{
name.length= name_arg->length;
name.str= memdup_root(mem_root, (char*) name_arg->str, name_arg->length);
return name.str == 0;
}
/**************************************************************************
Common parts of mysql_[sql]_stmt_prepare, mysql_[sql]_stmt_execute.
Essentially, these functions do all the magic of preparing/executing
a statement, leaving network communication, input data handling and
global THD state management to the caller.
***************************************************************************/
/*
Parse statement text, validate the statement, and prepare it for execution.
SYNOPSIS
Prepared_statement::prepare()
packet statement text
packet_len
DESCRIPTION
You should not change global THD state in this function, if at all
possible: it may be called from any context, e.g. when executing
a COM_* command, and SQLCOM_* command, or a stored procedure.
NOTES
Precondition.
-------------
The caller must ensure that thd->change_list and thd->free_list
is empty: this function will not back them up but will free
in the end of its execution.
Postcondition.
--------------
thd->mem_root contains unused memory allocated during validation.
*/
bool Prepared_statement::prepare(const char *packet, uint packet_len)
{
bool error;
Statement stmt_backup;
Query_arena *old_stmt_arena;
DBUG_ENTER("Prepared_statement::prepare");
/*
If this is an SQLCOM_PREPARE, we also increase Com_prepare_sql.
However, it seems handy if com_stmt_prepare is increased always,
no matter what kind of prepare is processed.
*/
statistic_increment(thd->status_var.com_stmt_prepare, &LOCK_status);
/*
alloc_query() uses thd->memroot && thd->query, so we should call
both of backup_statement() and backup_query_arena() here.
*/
thd->set_n_backup_statement(this, &stmt_backup);
thd->set_n_backup_active_arena(this, &stmt_backup);
if (alloc_query(thd, packet, packet_len))
{
thd->restore_backup_statement(this, &stmt_backup);
thd->restore_active_arena(this, &stmt_backup);
DBUG_RETURN(TRUE);
}
old_stmt_arena= thd->stmt_arena;
thd->stmt_arena= this;
lex_start(thd, (uchar*) thd->query, thd->query_length);
lex->stmt_prepare_mode= TRUE;
error= MYSQLparse((void *)thd) || thd->is_fatal_error ||
thd->net.report_error || init_param_array(this);
/*
The first thing we do after parse error is freeing sp_head to
ensure that we have restored original memroot.
*/
if (error && lex->sphead)
{
delete lex->sphead;
lex->sphead= NULL;
}
lex->safe_to_cache_query= FALSE;
/*
While doing context analysis of the query (in check_prepared_statement)
we allocate a lot of additional memory: for open tables, JOINs, derived
tables, etc. Let's save a snapshot of current parse tree to the
statement and restore original THD. In cases when some tree
transformation can be reused on execute, we set again thd->mem_root from
stmt->mem_root (see setup_wild for one place where we do that).
*/
thd->restore_active_arena(this, &stmt_backup);
/*
If called from a stored procedure, ensure that we won't rollback
external changes when cleaning up after validation.
*/
DBUG_ASSERT(thd->change_list.is_empty());
/*
The only case where we should have items in the thd->free_list is
after stmt->set_params_from_vars(), which may in some cases create
Item_null objects.
*/
if (error == 0)
error= check_prepared_statement(this, name.str != 0);
/* Free sp_head if check_prepared_statement() failed. */
if (error && lex->sphead)
{
delete lex->sphead;
lex->sphead= NULL;
}
lex_end(lex);
cleanup_stmt();
thd->restore_backup_statement(this, &stmt_backup);
thd->stmt_arena= old_stmt_arena;
if (error == 0)
{
setup_set_params();
init_stmt_after_parse(lex);
state= Query_arena::PREPARED;
flags&= ~ (uint) IS_IN_USE;
}
DBUG_RETURN(error);
}
/*
Execute a prepared statement.
SYNOPSIS
Prepared_statement::execute()
expanded_query A query for binlogging which has all parameter
markers ('?') replaced with their actual values.
open_cursor True if an attempt to open a cursor should be made.
Currenlty used only in the binary protocol.
DESCRIPTION
You should not change global THD state in this function, if at all
possible: it may be called from any context, e.g. when executing
a COM_* command, and SQLCOM_* command, or a stored procedure.
NOTES
Preconditions, postconditions.
------------------------------
See the comment for Prepared_statement::prepare().
RETURN
FALSE ok
TRUE Error
*/
bool Prepared_statement::execute(String *expanded_query, bool open_cursor)
{
Statement stmt_backup;
Query_arena *old_stmt_arena;
bool error= TRUE;
statistic_increment(thd->status_var.com_stmt_execute, &LOCK_status);
/* Check if we got an error when sending long data */
if (state == Query_arena::ERROR)
{
my_message(last_errno, last_error, MYF(0));
return TRUE;
}
if (flags & (uint) IS_IN_USE)
{
my_error(ER_PS_NO_RECURSION, MYF(0));
return TRUE;
}
/*
For SHOW VARIABLES lex->result is NULL, as it's a non-SELECT
command. For such queries we don't return an error and don't
open a cursor -- the client library will recognize this case and
materialize the result set.
For SELECT statements lex->result is created in
check_prepared_statement. lex->result->simple_select() is FALSE
in INSERT ... SELECT and similar commands.
*/
if (open_cursor && lex->result && !lex->result->simple_select())
{
DBUG_PRINT("info",("Cursor asked for not SELECT stmt"));
my_error(ER_SP_BAD_CURSOR_QUERY, MYF(0));
return TRUE;
}
/* In case the command has a call to SP which re-uses this statement name */
flags|= IS_IN_USE;
close_cursor();
/*
If the free_list is not empty, we'll wrongly free some externally
allocated items when cleaning up after execution of this statement.
*/
DBUG_ASSERT(thd->change_list.is_empty());
/*
The only case where we should have items in the thd->free_list is
after stmt->set_params_from_vars(), which may in some cases create
Item_null objects.
*/
thd->set_n_backup_statement(this, &stmt_backup);
if (expanded_query->length() &&
alloc_query(thd, (char*) expanded_query->ptr(),
expanded_query->length()+1))
{
my_error(ER_OUTOFMEMORY, 0, expanded_query->length());
goto error;
}
/*
Expanded query is needed for slow logging, so we want thd->query
to point at it even after we restore from backup. This is ok, as
expanded query was allocated in thd->mem_root.
*/
stmt_backup.query= thd->query;
stmt_backup.query_length= thd->query_length;
/*
At first execution of prepared statement we may perform logical
transformations of the query tree. Such changes should be performed
on the parse tree of current prepared statement and new items should
be allocated in its memory root. Set the appropriate pointer in THD
to the arena of the statement.
*/
old_stmt_arena= thd->stmt_arena;
thd->stmt_arena= this;
reinit_stmt_before_use(thd, lex);
thd->protocol= protocol; /* activate stmt protocol */
error= (open_cursor ?
mysql_open_cursor(thd, (uint) ALWAYS_MATERIALIZED_CURSOR,
&result, &cursor) :
mysql_execute_command(thd));
thd->protocol= &thd->protocol_simple; /* use normal protocol */
/* Assert that if an error, no cursor is open */
DBUG_ASSERT(! (error && cursor));
if (! cursor)
{
cleanup_stmt();
reset_stmt_params(this);
}
thd->set_statement(&stmt_backup);
thd->stmt_arena= old_stmt_arena;
if (state == Query_arena::PREPARED)
state= Query_arena::EXECUTED;
error:
flags&= ~ (uint) IS_IN_USE;
return error;
}
/* Common part of DEALLOCATE PREPARE and mysql_stmt_close */
bool Prepared_statement::deallocate()
{
/* We account deallocate in the same manner as mysql_stmt_close */
statistic_increment(thd->status_var.com_stmt_close, &LOCK_status);
if (flags & (uint) IS_IN_USE)
{
my_error(ER_PS_NO_RECURSION, MYF(0));
return TRUE;
}
/* Statement map calls delete stmt on erase */
thd->stmt_map.erase(this);
return FALSE;
}
|