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
3043
3044
3045
3046
3047
3048
3049
3050
3051
3052
3053
3054
3055
3056
3057
3058
3059
3060
3061
3062
3063
3064
3065
3066
3067
3068
3069
3070
3071
3072
3073
3074
3075
3076
3077
3078
3079
3080
3081
3082
3083
3084
3085
3086
3087
3088
3089
3090
3091
3092
3093
3094
3095
3096
3097
3098
3099
3100
3101
3102
3103
3104
3105
3106
3107
3108
3109
3110
3111
3112
3113
3114
3115
3116
3117
3118
3119
3120
3121
3122
3123
3124
3125
3126
3127
3128
3129
3130
3131
3132
3133
3134
3135
3136
3137
3138
3139
3140
3141
3142
3143
3144
3145
3146
3147
3148
3149
3150
3151
3152
3153
3154
3155
3156
3157
3158
3159
3160
3161
3162
3163
3164
3165
3166
3167
3168
3169
3170
3171
3172
3173
3174
3175
3176
3177
3178
3179
3180
3181
3182
3183
3184
3185
3186
3187
3188
3189
3190
3191
3192
3193
3194
3195
3196
3197
3198
3199
3200
3201
3202
3203
3204
3205
3206
3207
3208
3209
3210
3211
3212
3213
3214
3215
3216
3217
3218
3219
3220
3221
3222
3223
3224
3225
3226
3227
3228
3229
3230
3231
3232
3233
3234
3235
3236
3237
3238
3239
3240
3241
3242
3243
3244
3245
3246
3247
3248
3249
3250
3251
3252
3253
3254
3255
3256
3257
3258
3259
3260
3261
3262
3263
3264
3265
3266
3267
3268
3269
3270
3271
3272
3273
3274
3275
3276
3277
3278
3279
3280
3281
3282
3283
3284
3285
3286
3287
3288
3289
3290
3291
3292
3293
3294
3295
3296
3297
3298
3299
3300
3301
3302
3303
3304
3305
3306
3307
3308
3309
3310
3311
3312
3313
3314
3315
3316
3317
3318
3319
3320
3321
3322
3323
3324
3325
3326
3327
3328
3329
3330
3331
3332
3333
3334
3335
3336
3337
3338
3339
3340
3341
3342
3343
3344
3345
3346
3347
3348
3349
3350
3351
3352
3353
3354
3355
3356
3357
3358
3359
3360
3361
3362
3363
3364
3365
3366
3367
3368
3369
3370
3371
3372
3373
3374
3375
3376
3377
3378
3379
3380
3381
3382
3383
3384
3385
3386
3387
3388
3389
3390
3391
3392
3393
3394
3395
3396
3397
3398
3399
3400
3401
3402
3403
3404
3405
3406
3407
3408
3409
3410
3411
3412
3413
3414
3415
3416
3417
3418
3419
3420
3421
3422
3423
3424
3425
3426
3427
3428
3429
3430
3431
3432
3433
3434
3435
3436
3437
3438
3439
3440
3441
3442
3443
3444
3445
3446
3447
3448
3449
3450
3451
3452
3453
3454
3455
3456
3457
3458
3459
3460
3461
3462
3463
3464
3465
3466
3467
3468
3469
3470
3471
3472
3473
3474
3475
3476
3477
3478
3479
3480
3481
3482
3483
3484
3485
3486
3487
3488
3489
3490
3491
3492
3493
3494
3495
3496
3497
3498
3499
3500
3501
3502
3503
3504
3505
3506
3507
3508
3509
3510
3511
3512
3513
3514
3515
3516
3517
3518
3519
3520
3521
3522
3523
3524
3525
3526
3527
3528
3529
3530
3531
3532
3533
3534
3535
3536
3537
3538
3539
3540
3541
3542
3543
3544
3545
3546
3547
3548
3549
3550
3551
3552
3553
3554
3555
3556
3557
3558
3559
3560
3561
3562
3563
3564
3565
3566
3567
3568
3569
3570
3571
3572
3573
3574
3575
3576
3577
3578
3579
3580
3581
3582
3583
3584
3585
3586
3587
3588
3589
3590
3591
3592
3593
3594
3595
3596
3597
3598
3599
3600
3601
3602
3603
3604
3605
3606
3607
3608
3609
3610
3611
3612
3613
3614
3615
3616
3617
3618
3619
3620
3621
3622
3623
3624
3625
3626
3627
3628
3629
3630
3631
3632
3633
3634
3635
3636
3637
3638
3639
3640
3641
3642
3643
3644
3645
3646
3647
3648
3649
3650
3651
3652
3653
3654
3655
3656
3657
3658
3659
3660
3661
3662
3663
3664
3665
3666
3667
3668
3669
3670
3671
3672
3673
3674
3675
3676
3677
3678
3679
3680
3681
3682
3683
3684
3685
3686
3687
3688
3689
3690
3691
3692
3693
3694
3695
3696
3697
3698
3699
3700
3701
3702
3703
3704
3705
3706
3707
3708
3709
3710
3711
3712
3713
3714
3715
3716
3717
3718
3719
3720
3721
3722
3723
3724
3725
3726
3727
3728
3729
3730
3731
3732
3733
3734
3735
3736
3737
3738
3739
3740
3741
3742
3743
3744
3745
3746
3747
3748
3749
3750
3751
3752
3753
3754
3755
3756
3757
3758
3759
3760
3761
3762
3763
3764
3765
3766
3767
3768
3769
3770
3771
3772
3773
3774
3775
3776
3777
3778
3779
3780
3781
3782
3783
3784
3785
3786
3787
3788
3789
3790
3791
3792
3793
3794
3795
3796
3797
3798
3799
3800
3801
3802
3803
3804
3805
3806
3807
3808
3809
3810
3811
3812
3813
3814
3815
3816
3817
3818
3819
3820
3821
3822
3823
3824
3825
3826
3827
3828
3829
3830
3831
3832
3833
3834
3835
3836
3837
3838
3839
3840
3841
3842
3843
3844
3845
3846
3847
3848
3849
3850
3851
3852
3853
3854
3855
3856
3857
3858
3859
3860
3861
3862
3863
3864
3865
3866
3867
3868
3869
3870
3871
3872
3873
3874
3875
3876
3877
3878
3879
3880
3881
3882
3883
3884
3885
3886
3887
3888
3889
3890
3891
3892
3893
3894
3895
3896
3897
3898
3899
3900
3901
3902
3903
3904
3905
3906
3907
3908
3909
3910
3911
3912
3913
3914
3915
3916
3917
3918
3919
3920
3921
3922
3923
3924
3925
3926
3927
3928
3929
3930
3931
3932
3933
3934
3935
3936
3937
3938
3939
3940
3941
3942
3943
3944
3945
3946
3947
3948
3949
3950
3951
3952
3953
3954
3955
3956
3957
3958
3959
3960
3961
3962
3963
3964
3965
3966
3967
3968
3969
3970
3971
3972
3973
3974
3975
3976
3977
3978
3979
3980
3981
3982
3983
3984
3985
3986
3987
3988
3989
3990
3991
3992
3993
3994
3995
3996
3997
3998
3999
4000
4001
4002
4003
4004
4005
4006
4007
4008
4009
4010
4011
4012
4013
4014
4015
4016
4017
4018
4019
4020
4021
4022
4023
4024
4025
4026
4027
4028
4029
4030
4031
4032
4033
4034
4035
4036
4037
4038
4039
4040
4041
4042
4043
4044
4045
4046
4047
4048
4049
4050
4051
4052
4053
4054
4055
4056
4057
4058
4059
4060
4061
4062
4063
4064
4065
4066
4067
4068
4069
4070
4071
4072
4073
4074
4075
4076
4077
4078
4079
4080
4081
4082
4083
4084
4085
4086
4087
4088
4089
4090
4091
4092
4093
4094
4095
4096
4097
4098
4099
4100
4101
4102
4103
4104
4105
4106
4107
4108
4109
4110
4111
4112
4113
4114
4115
4116
4117
4118
4119
4120
4121
4122
4123
4124
4125
4126
4127
4128
4129
4130
4131
4132
4133
4134
4135
4136
4137
4138
4139
4140
4141
4142
4143
4144
4145
4146
4147
4148
4149
4150
4151
4152
4153
4154
4155
4156
4157
4158
4159
4160
4161
4162
4163
4164
4165
4166
4167
4168
4169
4170
4171
4172
4173
4174
4175
4176
4177
4178
4179
4180
4181
4182
4183
4184
4185
4186
4187
4188
4189
4190
4191
4192
4193
4194
4195
4196
4197
4198
4199
4200
4201
4202
4203
4204
4205
4206
4207
4208
4209
4210
4211
4212
4213
4214
4215
4216
4217
4218
4219
4220
4221
4222
4223
4224
4225
4226
4227
4228
4229
4230
4231
4232
4233
4234
4235
4236
4237
4238
4239
4240
4241
4242
4243
4244
4245
4246
4247
4248
4249
4250
4251
4252
4253
4254
4255
4256
4257
4258
4259
4260
4261
4262
4263
4264
4265
4266
4267
4268
4269
4270
4271
4272
4273
4274
4275
4276
4277
4278
4279
4280
4281
4282
4283
4284
4285
4286
4287
4288
4289
4290
4291
4292
4293
4294
4295
4296
4297
4298
4299
4300
4301
4302
4303
4304
4305
4306
4307
4308
4309
4310
4311
4312
4313
4314
4315
4316
4317
4318
4319
4320
4321
4322
4323
4324
4325
4326
4327
4328
4329
4330
4331
4332
4333
4334
4335
4336
4337
4338
4339
4340
4341
4342
4343
4344
4345
4346
4347
4348
4349
4350
4351
4352
4353
4354
4355
4356
4357
4358
4359
4360
4361
4362
4363
4364
4365
4366
4367
4368
4369
4370
4371
4372
4373
4374
4375
4376
4377
4378
4379
4380
4381
4382
4383
4384
4385
4386
4387
4388
4389
4390
4391
4392
4393
4394
4395
4396
4397
4398
4399
4400
4401
4402
4403
4404
4405
4406
4407
4408
4409
4410
4411
4412
4413
4414
4415
4416
4417
4418
4419
4420
4421
4422
4423
4424
4425
4426
4427
4428
4429
4430
4431
4432
4433
4434
4435
4436
4437
4438
4439
4440
4441
4442
4443
4444
4445
4446
4447
4448
4449
4450
4451
4452
4453
4454
4455
4456
4457
4458
4459
4460
4461
4462
4463
4464
4465
4466
4467
4468
4469
4470
4471
4472
4473
4474
4475
4476
4477
4478
4479
4480
4481
4482
4483
4484
4485
4486
4487
4488
4489
4490
4491
4492
4493
4494
4495
4496
4497
4498
4499
4500
4501
4502
4503
4504
4505
4506
4507
4508
4509
4510
4511
4512
4513
4514
4515
4516
4517
4518
4519
4520
4521
4522
4523
4524
4525
4526
4527
4528
4529
4530
4531
4532
4533
4534
4535
4536
4537
4538
4539
4540
4541
4542
4543
4544
4545
4546
4547
4548
4549
4550
4551
4552
4553
4554
4555
4556
4557
4558
4559
4560
4561
4562
4563
4564
4565
4566
4567
4568
4569
4570
4571
4572
4573
4574
4575
4576
4577
4578
4579
4580
4581
4582
4583
4584
4585
4586
4587
4588
4589
4590
4591
4592
4593
4594
4595
4596
4597
4598
4599
4600
4601
4602
4603
4604
4605
4606
4607
4608
4609
4610
4611
4612
4613
4614
4615
4616
4617
4618
4619
4620
4621
4622
4623
4624
4625
4626
4627
4628
4629
4630
4631
4632
4633
4634
4635
4636
4637
4638
4639
4640
4641
4642
4643
4644
4645
4646
4647
4648
4649
4650
4651
4652
4653
4654
4655
4656
4657
4658
4659
4660
4661
4662
4663
4664
4665
4666
4667
4668
4669
4670
4671
4672
4673
4674
4675
4676
4677
4678
4679
4680
4681
4682
4683
4684
4685
4686
4687
4688
4689
4690
4691
4692
4693
4694
4695
4696
4697
4698
4699
4700
4701
4702
4703
4704
4705
4706
4707
4708
4709
4710
4711
4712
4713
4714
4715
4716
4717
4718
4719
4720
4721
4722
4723
4724
4725
4726
4727
4728
4729
4730
4731
4732
4733
4734
4735
4736
4737
4738
4739
4740
4741
4742
4743
4744
4745
4746
4747
4748
4749
4750
4751
4752
4753
4754
4755
4756
4757
4758
4759
4760
4761
4762
4763
4764
4765
4766
4767
4768
4769
4770
4771
4772
4773
4774
4775
4776
4777
4778
4779
4780
4781
4782
4783
4784
4785
4786
4787
4788
4789
4790
4791
4792
4793
4794
4795
4796
4797
4798
4799
4800
4801
4802
4803
4804
4805
4806
4807
4808
4809
4810
4811
4812
4813
4814
4815
4816
4817
4818
4819
4820
4821
4822
4823
4824
4825
4826
4827
4828
4829
4830
4831
4832
4833
4834
4835
4836
4837
4838
4839
4840
4841
4842
4843
4844
4845
4846
4847
4848
4849
4850
4851
4852
4853
4854
4855
4856
4857
4858
4859
4860
4861
4862
4863
4864
4865
4866
4867
4868
4869
4870
4871
4872
4873
4874
4875
4876
4877
4878
4879
4880
4881
4882
4883
4884
4885
4886
4887
4888
4889
4890
4891
4892
4893
4894
4895
4896
4897
4898
4899
4900
4901
4902
4903
4904
4905
4906
4907
4908
4909
4910
4911
4912
4913
4914
4915
4916
4917
4918
4919
4920
4921
4922
4923
4924
4925
4926
4927
4928
4929
4930
4931
4932
4933
4934
4935
4936
4937
4938
4939
4940
4941
4942
4943
4944
4945
4946
4947
4948
4949
4950
4951
4952
4953
4954
4955
4956
4957
4958
4959
4960
4961
4962
4963
4964
4965
4966
4967
4968
4969
4970
4971
4972
4973
4974
4975
4976
4977
4978
4979
4980
4981
4982
4983
4984
4985
4986
4987
4988
4989
4990
4991
4992
4993
4994
4995
4996
4997
4998
4999
5000
5001
5002
5003
5004
5005
5006
5007
5008
5009
5010
5011
5012
5013
5014
5015
5016
5017
5018
5019
5020
5021
5022
5023
5024
5025
5026
5027
5028
5029
5030
5031
5032
5033
5034
5035
5036
5037
5038
5039
5040
5041
5042
5043
5044
5045
5046
5047
5048
5049
5050
5051
5052
5053
5054
5055
5056
5057
5058
5059
5060
5061
5062
5063
5064
5065
5066
5067
5068
5069
5070
5071
5072
5073
5074
5075
5076
5077
5078
5079
5080
5081
5082
5083
5084
5085
5086
5087
5088
5089
5090
5091
5092
5093
5094
5095
5096
5097
5098
5099
5100
5101
5102
5103
5104
5105
5106
5107
5108
5109
5110
5111
5112
5113
5114
5115
5116
5117
5118
5119
5120
5121
5122
5123
5124
5125
5126
5127
5128
5129
5130
5131
5132
5133
5134
5135
5136
5137
5138
5139
5140
5141
5142
5143
5144
5145
5146
5147
5148
5149
5150
5151
5152
5153
5154
5155
5156
5157
5158
5159
5160
5161
5162
5163
5164
5165
5166
5167
5168
5169
5170
5171
5172
5173
5174
5175
5176
5177
5178
5179
5180
5181
5182
5183
5184
5185
5186
5187
5188
5189
5190
5191
5192
5193
5194
5195
5196
5197
5198
5199
5200
5201
5202
5203
5204
5205
5206
5207
5208
5209
5210
5211
5212
5213
5214
5215
5216
5217
5218
5219
5220
5221
5222
5223
5224
5225
5226
5227
5228
5229
5230
5231
5232
5233
5234
5235
5236
5237
5238
5239
5240
5241
5242
5243
5244
5245
5246
5247
5248
5249
5250
5251
5252
5253
5254
5255
5256
5257
5258
5259
5260
5261
5262
5263
5264
5265
5266
5267
5268
5269
5270
5271
5272
5273
5274
5275
5276
5277
5278
5279
5280
5281
5282
5283
5284
5285
5286
5287
5288
5289
5290
5291
5292
5293
5294
5295
5296
5297
5298
5299
5300
5301
5302
5303
5304
5305
5306
5307
5308
5309
5310
5311
5312
5313
5314
5315
5316
5317
5318
5319
5320
5321
5322
5323
5324
5325
5326
5327
5328
5329
5330
5331
5332
5333
5334
5335
5336
5337
5338
5339
5340
5341
5342
5343
5344
5345
5346
5347
5348
5349
5350
5351
5352
5353
5354
5355
5356
5357
5358
5359
5360
5361
5362
5363
5364
5365
5366
5367
5368
5369
5370
5371
5372
5373
5374
5375
5376
5377
5378
5379
5380
5381
5382
|
/* Target-struct-independent code to start (run) and stop an inferior
process.
Copyright (C) 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995,
1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007,
2008 Free Software Foundation, Inc.
This file is part of GDB.
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 3 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, see <http://www.gnu.org/licenses/>. */
#include "defs.h"
#include "gdb_string.h"
#include <ctype.h>
#include "symtab.h"
#include "frame.h"
#include "inferior.h"
#include "exceptions.h"
#include "breakpoint.h"
#include "gdb_wait.h"
#include "gdbcore.h"
#include "gdbcmd.h"
#include "cli/cli-script.h"
#include "target.h"
#include "gdbthread.h"
#include "annotate.h"
#include "symfile.h"
#include "top.h"
#include <signal.h>
#include "inf-loop.h"
#include "regcache.h"
#include "value.h"
#include "observer.h"
#include "language.h"
#include "solib.h"
#include "main.h"
#include "gdb_assert.h"
#include "mi/mi-common.h"
#include "event-top.h"
/* Prototypes for local functions */
static void signals_info (char *, int);
static void handle_command (char *, int);
static void sig_print_info (enum target_signal);
static void sig_print_header (void);
static void resume_cleanups (void *);
static int hook_stop_stub (void *);
static int restore_selected_frame (void *);
static void build_infrun (void);
static int follow_fork (void);
static void set_schedlock_func (char *args, int from_tty,
struct cmd_list_element *c);
static int currently_stepping (struct thread_info *tp);
static int currently_stepping_callback (struct thread_info *tp, void *data);
static void xdb_handle_command (char *args, int from_tty);
static int prepare_to_proceed (int);
void _initialize_infrun (void);
/* When set, stop the 'step' command if we enter a function which has
no line number information. The normal behavior is that we step
over such function. */
int step_stop_if_no_debug = 0;
static void
show_step_stop_if_no_debug (struct ui_file *file, int from_tty,
struct cmd_list_element *c, const char *value)
{
fprintf_filtered (file, _("Mode of the step operation is %s.\n"), value);
}
/* In asynchronous mode, but simulating synchronous execution. */
int sync_execution = 0;
/* wait_for_inferior and normal_stop use this to notify the user
when the inferior stopped in a different thread than it had been
running in. */
static ptid_t previous_inferior_ptid;
int debug_displaced = 0;
static void
show_debug_displaced (struct ui_file *file, int from_tty,
struct cmd_list_element *c, const char *value)
{
fprintf_filtered (file, _("Displace stepping debugging is %s.\n"), value);
}
static int debug_infrun = 0;
static void
show_debug_infrun (struct ui_file *file, int from_tty,
struct cmd_list_element *c, const char *value)
{
fprintf_filtered (file, _("Inferior debugging is %s.\n"), value);
}
/* If the program uses ELF-style shared libraries, then calls to
functions in shared libraries go through stubs, which live in a
table called the PLT (Procedure Linkage Table). The first time the
function is called, the stub sends control to the dynamic linker,
which looks up the function's real address, patches the stub so
that future calls will go directly to the function, and then passes
control to the function.
If we are stepping at the source level, we don't want to see any of
this --- we just want to skip over the stub and the dynamic linker.
The simple approach is to single-step until control leaves the
dynamic linker.
However, on some systems (e.g., Red Hat's 5.2 distribution) the
dynamic linker calls functions in the shared C library, so you
can't tell from the PC alone whether the dynamic linker is still
running. In this case, we use a step-resume breakpoint to get us
past the dynamic linker, as if we were using "next" to step over a
function call.
in_solib_dynsym_resolve_code() says whether we're in the dynamic
linker code or not. Normally, this means we single-step. However,
if SKIP_SOLIB_RESOLVER then returns non-zero, then its value is an
address where we can place a step-resume breakpoint to get past the
linker's symbol resolution function.
in_solib_dynsym_resolve_code() can generally be implemented in a
pretty portable way, by comparing the PC against the address ranges
of the dynamic linker's sections.
SKIP_SOLIB_RESOLVER is generally going to be system-specific, since
it depends on internal details of the dynamic linker. It's usually
not too hard to figure out where to put a breakpoint, but it
certainly isn't portable. SKIP_SOLIB_RESOLVER should do plenty of
sanity checking. If it can't figure things out, returning zero and
getting the (possibly confusing) stepping behavior is better than
signalling an error, which will obscure the change in the
inferior's state. */
/* This function returns TRUE if pc is the address of an instruction
that lies within the dynamic linker (such as the event hook, or the
dld itself).
This function must be used only when a dynamic linker event has
been caught, and the inferior is being stepped out of the hook, or
undefined results are guaranteed. */
#ifndef SOLIB_IN_DYNAMIC_LINKER
#define SOLIB_IN_DYNAMIC_LINKER(pid,pc) 0
#endif
/* Convert the #defines into values. This is temporary until wfi control
flow is completely sorted out. */
#ifndef CANNOT_STEP_HW_WATCHPOINTS
#define CANNOT_STEP_HW_WATCHPOINTS 0
#else
#undef CANNOT_STEP_HW_WATCHPOINTS
#define CANNOT_STEP_HW_WATCHPOINTS 1
#endif
/* Tables of how to react to signals; the user sets them. */
static unsigned char *signal_stop;
static unsigned char *signal_print;
static unsigned char *signal_program;
#define SET_SIGS(nsigs,sigs,flags) \
do { \
int signum = (nsigs); \
while (signum-- > 0) \
if ((sigs)[signum]) \
(flags)[signum] = 1; \
} while (0)
#define UNSET_SIGS(nsigs,sigs,flags) \
do { \
int signum = (nsigs); \
while (signum-- > 0) \
if ((sigs)[signum]) \
(flags)[signum] = 0; \
} while (0)
/* Value to pass to target_resume() to cause all threads to resume */
#define RESUME_ALL (pid_to_ptid (-1))
/* Command list pointer for the "stop" placeholder. */
static struct cmd_list_element *stop_command;
/* Function inferior was in as of last step command. */
static struct symbol *step_start_function;
/* Nonzero if we want to give control to the user when we're notified
of shared library events by the dynamic linker. */
static int stop_on_solib_events;
static void
show_stop_on_solib_events (struct ui_file *file, int from_tty,
struct cmd_list_element *c, const char *value)
{
fprintf_filtered (file, _("Stopping for shared library events is %s.\n"),
value);
}
/* Nonzero means expecting a trace trap
and should stop the inferior and return silently when it happens. */
int stop_after_trap;
/* Save register contents here when executing a "finish" command or are
about to pop a stack dummy frame, if-and-only-if proceed_to_finish is set.
Thus this contains the return value from the called function (assuming
values are returned in a register). */
struct regcache *stop_registers;
/* Nonzero after stop if current stack frame should be printed. */
static int stop_print_frame;
/* This is a cached copy of the pid/waitstatus of the last event
returned by target_wait()/deprecated_target_wait_hook(). This
information is returned by get_last_target_status(). */
static ptid_t target_last_wait_ptid;
static struct target_waitstatus target_last_waitstatus;
static void context_switch (ptid_t ptid);
void init_thread_stepping_state (struct thread_info *tss);
void init_infwait_state (void);
/* This is used to remember when a fork, vfork or exec event
was caught by a catchpoint, and thus the event is to be
followed at the next resume of the inferior, and not
immediately. */
static struct
{
enum target_waitkind kind;
struct
{
ptid_t parent_pid;
ptid_t child_pid;
}
fork_event;
char *execd_pathname;
}
pending_follow;
static const char follow_fork_mode_child[] = "child";
static const char follow_fork_mode_parent[] = "parent";
static const char *follow_fork_mode_kind_names[] = {
follow_fork_mode_child,
follow_fork_mode_parent,
NULL
};
static const char *follow_fork_mode_string = follow_fork_mode_parent;
static void
show_follow_fork_mode_string (struct ui_file *file, int from_tty,
struct cmd_list_element *c, const char *value)
{
fprintf_filtered (file, _("\
Debugger response to a program call of fork or vfork is \"%s\".\n"),
value);
}
static int
follow_fork (void)
{
int follow_child = (follow_fork_mode_string == follow_fork_mode_child);
return target_follow_fork (follow_child);
}
void
follow_inferior_reset_breakpoints (void)
{
struct thread_info *tp = inferior_thread ();
/* Was there a step_resume breakpoint? (There was if the user
did a "next" at the fork() call.) If so, explicitly reset its
thread number.
step_resumes are a form of bp that are made to be per-thread.
Since we created the step_resume bp when the parent process
was being debugged, and now are switching to the child process,
from the breakpoint package's viewpoint, that's a switch of
"threads". We must update the bp's notion of which thread
it is for, or it'll be ignored when it triggers. */
if (tp->step_resume_breakpoint)
breakpoint_re_set_thread (tp->step_resume_breakpoint);
/* Reinsert all breakpoints in the child. The user may have set
breakpoints after catching the fork, in which case those
were never set in the child, but only in the parent. This makes
sure the inserted breakpoints match the breakpoint list. */
breakpoint_re_set ();
insert_breakpoints ();
}
/* EXECD_PATHNAME is assumed to be non-NULL. */
static void
follow_exec (ptid_t pid, char *execd_pathname)
{
struct target_ops *tgt;
struct thread_info *th = inferior_thread ();
/* This is an exec event that we actually wish to pay attention to.
Refresh our symbol table to the newly exec'd program, remove any
momentary bp's, etc.
If there are breakpoints, they aren't really inserted now,
since the exec() transformed our inferior into a fresh set
of instructions.
We want to preserve symbolic breakpoints on the list, since
we have hopes that they can be reset after the new a.out's
symbol table is read.
However, any "raw" breakpoints must be removed from the list
(e.g., the solib bp's), since their address is probably invalid
now.
And, we DON'T want to call delete_breakpoints() here, since
that may write the bp's "shadow contents" (the instruction
value that was overwritten witha TRAP instruction). Since
we now have a new a.out, those shadow contents aren't valid. */
update_breakpoints_after_exec ();
/* If there was one, it's gone now. We cannot truly step-to-next
statement through an exec(). */
th->step_resume_breakpoint = NULL;
th->step_range_start = 0;
th->step_range_end = 0;
/* What is this a.out's name? */
printf_unfiltered (_("Executing new program: %s\n"), execd_pathname);
/* We've followed the inferior through an exec. Therefore, the
inferior has essentially been killed & reborn. */
gdb_flush (gdb_stdout);
breakpoint_init_inferior (inf_execd);
if (gdb_sysroot && *gdb_sysroot)
{
char *name = alloca (strlen (gdb_sysroot)
+ strlen (execd_pathname)
+ 1);
strcpy (name, gdb_sysroot);
strcat (name, execd_pathname);
execd_pathname = name;
}
/* That a.out is now the one to use. */
exec_file_attach (execd_pathname, 0);
/* Reset the shared library package. This ensures that we get a
shlib event when the child reaches "_start", at which point the
dld will have had a chance to initialize the child. */
/* Also, loading a symbol file below may trigger symbol lookups, and
we don't want those to be satisfied by the libraries of the
previous incarnation of this process. */
no_shared_libraries (NULL, 0);
/* Load the main file's symbols. */
symbol_file_add_main (execd_pathname, 0);
#ifdef SOLIB_CREATE_INFERIOR_HOOK
SOLIB_CREATE_INFERIOR_HOOK (PIDGET (inferior_ptid));
#else
solib_create_inferior_hook ();
#endif
/* Reinsert all breakpoints. (Those which were symbolic have
been reset to the proper address in the new a.out, thanks
to symbol_file_command...) */
insert_breakpoints ();
/* The next resume of this inferior should bring it to the shlib
startup breakpoints. (If the user had also set bp's on
"main" from the old (parent) process, then they'll auto-
matically get reset there in the new process.) */
}
/* Non-zero if we just simulating a single-step. This is needed
because we cannot remove the breakpoints in the inferior process
until after the `wait' in `wait_for_inferior'. */
static int singlestep_breakpoints_inserted_p = 0;
/* The thread we inserted single-step breakpoints for. */
static ptid_t singlestep_ptid;
/* PC when we started this single-step. */
static CORE_ADDR singlestep_pc;
/* If another thread hit the singlestep breakpoint, we save the original
thread here so that we can resume single-stepping it later. */
static ptid_t saved_singlestep_ptid;
static int stepping_past_singlestep_breakpoint;
/* If not equal to null_ptid, this means that after stepping over breakpoint
is finished, we need to switch to deferred_step_ptid, and step it.
The use case is when one thread has hit a breakpoint, and then the user
has switched to another thread and issued 'step'. We need to step over
breakpoint in the thread which hit the breakpoint, but then continue
stepping the thread user has selected. */
static ptid_t deferred_step_ptid;
/* Displaced stepping. */
/* In non-stop debugging mode, we must take special care to manage
breakpoints properly; in particular, the traditional strategy for
stepping a thread past a breakpoint it has hit is unsuitable.
'Displaced stepping' is a tactic for stepping one thread past a
breakpoint it has hit while ensuring that other threads running
concurrently will hit the breakpoint as they should.
The traditional way to step a thread T off a breakpoint in a
multi-threaded program in all-stop mode is as follows:
a0) Initially, all threads are stopped, and breakpoints are not
inserted.
a1) We single-step T, leaving breakpoints uninserted.
a2) We insert breakpoints, and resume all threads.
In non-stop debugging, however, this strategy is unsuitable: we
don't want to have to stop all threads in the system in order to
continue or step T past a breakpoint. Instead, we use displaced
stepping:
n0) Initially, T is stopped, other threads are running, and
breakpoints are inserted.
n1) We copy the instruction "under" the breakpoint to a separate
location, outside the main code stream, making any adjustments
to the instruction, register, and memory state as directed by
T's architecture.
n2) We single-step T over the instruction at its new location.
n3) We adjust the resulting register and memory state as directed
by T's architecture. This includes resetting T's PC to point
back into the main instruction stream.
n4) We resume T.
This approach depends on the following gdbarch methods:
- gdbarch_max_insn_length and gdbarch_displaced_step_location
indicate where to copy the instruction, and how much space must
be reserved there. We use these in step n1.
- gdbarch_displaced_step_copy_insn copies a instruction to a new
address, and makes any necessary adjustments to the instruction,
register contents, and memory. We use this in step n1.
- gdbarch_displaced_step_fixup adjusts registers and memory after
we have successfuly single-stepped the instruction, to yield the
same effect the instruction would have had if we had executed it
at its original address. We use this in step n3.
- gdbarch_displaced_step_free_closure provides cleanup.
The gdbarch_displaced_step_copy_insn and
gdbarch_displaced_step_fixup functions must be written so that
copying an instruction with gdbarch_displaced_step_copy_insn,
single-stepping across the copied instruction, and then applying
gdbarch_displaced_insn_fixup should have the same effects on the
thread's memory and registers as stepping the instruction in place
would have. Exactly which responsibilities fall to the copy and
which fall to the fixup is up to the author of those functions.
See the comments in gdbarch.sh for details.
Note that displaced stepping and software single-step cannot
currently be used in combination, although with some care I think
they could be made to. Software single-step works by placing
breakpoints on all possible subsequent instructions; if the
displaced instruction is a PC-relative jump, those breakpoints
could fall in very strange places --- on pages that aren't
executable, or at addresses that are not proper instruction
boundaries. (We do generally let other threads run while we wait
to hit the software single-step breakpoint, and they might
encounter such a corrupted instruction.) One way to work around
this would be to have gdbarch_displaced_step_copy_insn fully
simulate the effect of PC-relative instructions (and return NULL)
on architectures that use software single-stepping.
In non-stop mode, we can have independent and simultaneous step
requests, so more than one thread may need to simultaneously step
over a breakpoint. The current implementation assumes there is
only one scratch space per process. In this case, we have to
serialize access to the scratch space. If thread A wants to step
over a breakpoint, but we are currently waiting for some other
thread to complete a displaced step, we leave thread A stopped and
place it in the displaced_step_request_queue. Whenever a displaced
step finishes, we pick the next thread in the queue and start a new
displaced step operation on it. See displaced_step_prepare and
displaced_step_fixup for details. */
/* If this is not null_ptid, this is the thread carrying out a
displaced single-step. This thread's state will require fixing up
once it has completed its step. */
static ptid_t displaced_step_ptid;
struct displaced_step_request
{
ptid_t ptid;
struct displaced_step_request *next;
};
/* A queue of pending displaced stepping requests. */
struct displaced_step_request *displaced_step_request_queue;
/* The architecture the thread had when we stepped it. */
static struct gdbarch *displaced_step_gdbarch;
/* The closure provided gdbarch_displaced_step_copy_insn, to be used
for post-step cleanup. */
static struct displaced_step_closure *displaced_step_closure;
/* The address of the original instruction, and the copy we made. */
static CORE_ADDR displaced_step_original, displaced_step_copy;
/* Saved contents of copy area. */
static gdb_byte *displaced_step_saved_copy;
/* Enum strings for "set|show displaced-stepping". */
static const char can_use_displaced_stepping_auto[] = "auto";
static const char can_use_displaced_stepping_on[] = "on";
static const char can_use_displaced_stepping_off[] = "off";
static const char *can_use_displaced_stepping_enum[] =
{
can_use_displaced_stepping_auto,
can_use_displaced_stepping_on,
can_use_displaced_stepping_off,
NULL,
};
/* If ON, and the architecture supports it, GDB will use displaced
stepping to step over breakpoints. If OFF, or if the architecture
doesn't support it, GDB will instead use the traditional
hold-and-step approach. If AUTO (which is the default), GDB will
decide which technique to use to step over breakpoints depending on
which of all-stop or non-stop mode is active --- displaced stepping
in non-stop mode; hold-and-step in all-stop mode. */
static const char *can_use_displaced_stepping =
can_use_displaced_stepping_auto;
static void
show_can_use_displaced_stepping (struct ui_file *file, int from_tty,
struct cmd_list_element *c,
const char *value)
{
if (can_use_displaced_stepping == can_use_displaced_stepping_auto)
fprintf_filtered (file, _("\
Debugger's willingness to use displaced stepping to step over \
breakpoints is %s (currently %s).\n"),
value, non_stop ? "on" : "off");
else
fprintf_filtered (file, _("\
Debugger's willingness to use displaced stepping to step over \
breakpoints is %s.\n"), value);
}
/* Return non-zero if displaced stepping can/should be used to step
over breakpoints. */
static int
use_displaced_stepping (struct gdbarch *gdbarch)
{
return (((can_use_displaced_stepping == can_use_displaced_stepping_auto
&& non_stop)
|| can_use_displaced_stepping == can_use_displaced_stepping_on)
&& gdbarch_displaced_step_copy_insn_p (gdbarch));
}
/* Clean out any stray displaced stepping state. */
static void
displaced_step_clear (void)
{
/* Indicate that there is no cleanup pending. */
displaced_step_ptid = null_ptid;
if (displaced_step_closure)
{
gdbarch_displaced_step_free_closure (displaced_step_gdbarch,
displaced_step_closure);
displaced_step_closure = NULL;
}
}
static void
cleanup_displaced_step_closure (void *ptr)
{
struct displaced_step_closure *closure = ptr;
gdbarch_displaced_step_free_closure (current_gdbarch, closure);
}
/* Dump LEN bytes at BUF in hex to FILE, followed by a newline. */
void
displaced_step_dump_bytes (struct ui_file *file,
const gdb_byte *buf,
size_t len)
{
int i;
for (i = 0; i < len; i++)
fprintf_unfiltered (file, "%02x ", buf[i]);
fputs_unfiltered ("\n", file);
}
/* Prepare to single-step, using displaced stepping.
Note that we cannot use displaced stepping when we have a signal to
deliver. If we have a signal to deliver and an instruction to step
over, then after the step, there will be no indication from the
target whether the thread entered a signal handler or ignored the
signal and stepped over the instruction successfully --- both cases
result in a simple SIGTRAP. In the first case we mustn't do a
fixup, and in the second case we must --- but we can't tell which.
Comments in the code for 'random signals' in handle_inferior_event
explain how we handle this case instead.
Returns 1 if preparing was successful -- this thread is going to be
stepped now; or 0 if displaced stepping this thread got queued. */
static int
displaced_step_prepare (ptid_t ptid)
{
struct cleanup *old_cleanups, *ignore_cleanups;
struct regcache *regcache = get_thread_regcache (ptid);
struct gdbarch *gdbarch = get_regcache_arch (regcache);
CORE_ADDR original, copy;
ULONGEST len;
struct displaced_step_closure *closure;
/* We should never reach this function if the architecture does not
support displaced stepping. */
gdb_assert (gdbarch_displaced_step_copy_insn_p (gdbarch));
/* For the first cut, we're displaced stepping one thread at a
time. */
if (!ptid_equal (displaced_step_ptid, null_ptid))
{
/* Already waiting for a displaced step to finish. Defer this
request and place in queue. */
struct displaced_step_request *req, *new_req;
if (debug_displaced)
fprintf_unfiltered (gdb_stdlog,
"displaced: defering step of %s\n",
target_pid_to_str (ptid));
new_req = xmalloc (sizeof (*new_req));
new_req->ptid = ptid;
new_req->next = NULL;
if (displaced_step_request_queue)
{
for (req = displaced_step_request_queue;
req && req->next;
req = req->next)
;
req->next = new_req;
}
else
displaced_step_request_queue = new_req;
return 0;
}
else
{
if (debug_displaced)
fprintf_unfiltered (gdb_stdlog,
"displaced: stepping %s now\n",
target_pid_to_str (ptid));
}
displaced_step_clear ();
old_cleanups = save_inferior_ptid ();
inferior_ptid = ptid;
original = regcache_read_pc (regcache);
copy = gdbarch_displaced_step_location (gdbarch);
len = gdbarch_max_insn_length (gdbarch);
/* Save the original contents of the copy area. */
displaced_step_saved_copy = xmalloc (len);
ignore_cleanups = make_cleanup (free_current_contents,
&displaced_step_saved_copy);
read_memory (copy, displaced_step_saved_copy, len);
if (debug_displaced)
{
fprintf_unfiltered (gdb_stdlog, "displaced: saved 0x%s: ",
paddr_nz (copy));
displaced_step_dump_bytes (gdb_stdlog, displaced_step_saved_copy, len);
};
closure = gdbarch_displaced_step_copy_insn (gdbarch,
original, copy, regcache);
/* We don't support the fully-simulated case at present. */
gdb_assert (closure);
make_cleanup (cleanup_displaced_step_closure, closure);
/* Resume execution at the copy. */
regcache_write_pc (regcache, copy);
discard_cleanups (ignore_cleanups);
do_cleanups (old_cleanups);
if (debug_displaced)
fprintf_unfiltered (gdb_stdlog, "displaced: displaced pc to 0x%s\n",
paddr_nz (copy));
/* Save the information we need to fix things up if the step
succeeds. */
displaced_step_ptid = ptid;
displaced_step_gdbarch = gdbarch;
displaced_step_closure = closure;
displaced_step_original = original;
displaced_step_copy = copy;
return 1;
}
static void
displaced_step_clear_cleanup (void *ignore)
{
displaced_step_clear ();
}
static void
write_memory_ptid (ptid_t ptid, CORE_ADDR memaddr, const gdb_byte *myaddr, int len)
{
struct cleanup *ptid_cleanup = save_inferior_ptid ();
inferior_ptid = ptid;
write_memory (memaddr, myaddr, len);
do_cleanups (ptid_cleanup);
}
static void
displaced_step_fixup (ptid_t event_ptid, enum target_signal signal)
{
struct cleanup *old_cleanups;
/* Was this event for the pid we displaced? */
if (ptid_equal (displaced_step_ptid, null_ptid)
|| ! ptid_equal (displaced_step_ptid, event_ptid))
return;
old_cleanups = make_cleanup (displaced_step_clear_cleanup, 0);
/* Restore the contents of the copy area. */
{
ULONGEST len = gdbarch_max_insn_length (displaced_step_gdbarch);
write_memory_ptid (displaced_step_ptid, displaced_step_copy,
displaced_step_saved_copy, len);
if (debug_displaced)
fprintf_unfiltered (gdb_stdlog, "displaced: restored 0x%s\n",
paddr_nz (displaced_step_copy));
}
/* Did the instruction complete successfully? */
if (signal == TARGET_SIGNAL_TRAP)
{
/* Fix up the resulting state. */
gdbarch_displaced_step_fixup (displaced_step_gdbarch,
displaced_step_closure,
displaced_step_original,
displaced_step_copy,
get_thread_regcache (displaced_step_ptid));
}
else
{
/* Since the instruction didn't complete, all we can do is
relocate the PC. */
struct regcache *regcache = get_thread_regcache (event_ptid);
CORE_ADDR pc = regcache_read_pc (regcache);
pc = displaced_step_original + (pc - displaced_step_copy);
regcache_write_pc (regcache, pc);
}
do_cleanups (old_cleanups);
displaced_step_ptid = null_ptid;
/* Are there any pending displaced stepping requests? If so, run
one now. */
while (displaced_step_request_queue)
{
struct displaced_step_request *head;
ptid_t ptid;
CORE_ADDR actual_pc;
head = displaced_step_request_queue;
ptid = head->ptid;
displaced_step_request_queue = head->next;
xfree (head);
context_switch (ptid);
actual_pc = read_pc ();
if (breakpoint_here_p (actual_pc))
{
if (debug_displaced)
fprintf_unfiltered (gdb_stdlog,
"displaced: stepping queued %s now\n",
target_pid_to_str (ptid));
displaced_step_prepare (ptid);
if (debug_displaced)
{
gdb_byte buf[4];
fprintf_unfiltered (gdb_stdlog, "displaced: run 0x%s: ",
paddr_nz (actual_pc));
read_memory (actual_pc, buf, sizeof (buf));
displaced_step_dump_bytes (gdb_stdlog, buf, sizeof (buf));
}
target_resume (ptid, 1, TARGET_SIGNAL_0);
/* Done, we're stepping a thread. */
break;
}
else
{
int step;
struct thread_info *tp = inferior_thread ();
/* The breakpoint we were sitting under has since been
removed. */
tp->trap_expected = 0;
/* Go back to what we were trying to do. */
step = currently_stepping (tp);
if (debug_displaced)
fprintf_unfiltered (gdb_stdlog, "breakpoint is gone %s: step(%d)\n",
target_pid_to_str (tp->ptid), step);
target_resume (ptid, step, TARGET_SIGNAL_0);
tp->stop_signal = TARGET_SIGNAL_0;
/* This request was discarded. See if there's any other
thread waiting for its turn. */
}
}
}
/* Update global variables holding ptids to hold NEW_PTID if they were
holding OLD_PTID. */
static void
infrun_thread_ptid_changed (ptid_t old_ptid, ptid_t new_ptid)
{
struct displaced_step_request *it;
if (ptid_equal (inferior_ptid, old_ptid))
inferior_ptid = new_ptid;
if (ptid_equal (singlestep_ptid, old_ptid))
singlestep_ptid = new_ptid;
if (ptid_equal (displaced_step_ptid, old_ptid))
displaced_step_ptid = new_ptid;
if (ptid_equal (deferred_step_ptid, old_ptid))
deferred_step_ptid = new_ptid;
for (it = displaced_step_request_queue; it; it = it->next)
if (ptid_equal (it->ptid, old_ptid))
it->ptid = new_ptid;
}
/* Resuming. */
/* Things to clean up if we QUIT out of resume (). */
static void
resume_cleanups (void *ignore)
{
normal_stop ();
}
static const char schedlock_off[] = "off";
static const char schedlock_on[] = "on";
static const char schedlock_step[] = "step";
static const char *scheduler_enums[] = {
schedlock_off,
schedlock_on,
schedlock_step,
NULL
};
static const char *scheduler_mode = schedlock_off;
static void
show_scheduler_mode (struct ui_file *file, int from_tty,
struct cmd_list_element *c, const char *value)
{
fprintf_filtered (file, _("\
Mode for locking scheduler during execution is \"%s\".\n"),
value);
}
static void
set_schedlock_func (char *args, int from_tty, struct cmd_list_element *c)
{
if (!target_can_lock_scheduler)
{
scheduler_mode = schedlock_off;
error (_("Target '%s' cannot support this command."), target_shortname);
}
}
/* Resume the inferior, but allow a QUIT. This is useful if the user
wants to interrupt some lengthy single-stepping operation
(for child processes, the SIGINT goes to the inferior, and so
we get a SIGINT random_signal, but for remote debugging and perhaps
other targets, that's not true).
STEP nonzero if we should step (zero to continue instead).
SIG is the signal to give the inferior (zero for none). */
void
resume (int step, enum target_signal sig)
{
int should_resume = 1;
struct cleanup *old_cleanups = make_cleanup (resume_cleanups, 0);
/* Note that these must be reset if we follow a fork below. */
struct regcache *regcache = get_current_regcache ();
struct gdbarch *gdbarch = get_regcache_arch (regcache);
struct thread_info *tp = inferior_thread ();
CORE_ADDR pc = regcache_read_pc (regcache);
QUIT;
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog,
"infrun: resume (step=%d, signal=%d), "
"trap_expected=%d\n",
step, sig, tp->trap_expected);
/* Some targets (e.g. Solaris x86) have a kernel bug when stepping
over an instruction that causes a page fault without triggering
a hardware watchpoint. The kernel properly notices that it shouldn't
stop, because the hardware watchpoint is not triggered, but it forgets
the step request and continues the program normally.
Work around the problem by removing hardware watchpoints if a step is
requested, GDB will check for a hardware watchpoint trigger after the
step anyway. */
if (CANNOT_STEP_HW_WATCHPOINTS && step)
remove_hw_watchpoints ();
/* Normally, by the time we reach `resume', the breakpoints are either
removed or inserted, as appropriate. The exception is if we're sitting
at a permanent breakpoint; we need to step over it, but permanent
breakpoints can't be removed. So we have to test for it here. */
if (breakpoint_here_p (pc) == permanent_breakpoint_here)
{
if (gdbarch_skip_permanent_breakpoint_p (gdbarch))
gdbarch_skip_permanent_breakpoint (gdbarch, regcache);
else
error (_("\
The program is stopped at a permanent breakpoint, but GDB does not know\n\
how to step past a permanent breakpoint on this architecture. Try using\n\
a command like `return' or `jump' to continue execution."));
}
/* If enabled, step over breakpoints by executing a copy of the
instruction at a different address.
We can't use displaced stepping when we have a signal to deliver;
the comments for displaced_step_prepare explain why. The
comments in the handle_inferior event for dealing with 'random
signals' explain what we do instead. */
if (use_displaced_stepping (gdbarch)
&& tp->trap_expected
&& sig == TARGET_SIGNAL_0)
{
if (!displaced_step_prepare (inferior_ptid))
{
/* Got placed in displaced stepping queue. Will be resumed
later when all the currently queued displaced stepping
requests finish. The thread is not executing at this point,
and the call to set_executing will be made later. But we
need to call set_running here, since from frontend point of view,
the thread is running. */
set_running (inferior_ptid, 1);
discard_cleanups (old_cleanups);
return;
}
}
if (step && gdbarch_software_single_step_p (gdbarch))
{
/* Do it the hard way, w/temp breakpoints */
if (gdbarch_software_single_step (gdbarch, get_current_frame ()))
{
/* ...and don't ask hardware to do it. */
step = 0;
/* and do not pull these breakpoints until after a `wait' in
`wait_for_inferior' */
singlestep_breakpoints_inserted_p = 1;
singlestep_ptid = inferior_ptid;
singlestep_pc = pc;
}
}
/* If there were any forks/vforks/execs that were caught and are
now to be followed, then do so. */
switch (pending_follow.kind)
{
case TARGET_WAITKIND_FORKED:
case TARGET_WAITKIND_VFORKED:
pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
if (follow_fork ())
should_resume = 0;
/* Following a child fork will change our notion of current
thread. */
tp = inferior_thread ();
regcache = get_current_regcache ();
gdbarch = get_regcache_arch (regcache);
pc = regcache_read_pc (regcache);
break;
case TARGET_WAITKIND_EXECD:
/* follow_exec is called as soon as the exec event is seen. */
pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
break;
default:
break;
}
/* Install inferior's terminal modes. */
target_terminal_inferior ();
if (should_resume)
{
ptid_t resume_ptid;
resume_ptid = RESUME_ALL; /* Default */
/* If STEP is set, it's a request to use hardware stepping
facilities. But in that case, we should never
use singlestep breakpoint. */
gdb_assert (!(singlestep_breakpoints_inserted_p && step));
if (singlestep_breakpoints_inserted_p
&& stepping_past_singlestep_breakpoint)
{
/* The situation here is as follows. In thread T1 we wanted to
single-step. Lacking hardware single-stepping we've
set breakpoint at the PC of the next instruction -- call it
P. After resuming, we've hit that breakpoint in thread T2.
Now we've removed original breakpoint, inserted breakpoint
at P+1, and try to step to advance T2 past breakpoint.
We need to step only T2, as if T1 is allowed to freely run,
it can run past P, and if other threads are allowed to run,
they can hit breakpoint at P+1, and nested hits of single-step
breakpoints is not something we'd want -- that's complicated
to support, and has no value. */
resume_ptid = inferior_ptid;
}
if ((step || singlestep_breakpoints_inserted_p)
&& tp->trap_expected)
{
/* We're allowing a thread to run past a breakpoint it has
hit, by single-stepping the thread with the breakpoint
removed. In which case, we need to single-step only this
thread, and keep others stopped, as they can miss this
breakpoint if allowed to run.
The current code actually removes all breakpoints when
doing this, not just the one being stepped over, so if we
let other threads run, we can actually miss any
breakpoint, not just the one at PC. */
resume_ptid = inferior_ptid;
}
if (non_stop)
{
/* With non-stop mode on, threads are always handled
individually. */
resume_ptid = inferior_ptid;
}
else if ((scheduler_mode == schedlock_on)
|| (scheduler_mode == schedlock_step
&& (step || singlestep_breakpoints_inserted_p)))
{
/* User-settable 'scheduler' mode requires solo thread resume. */
resume_ptid = inferior_ptid;
}
if (gdbarch_cannot_step_breakpoint (gdbarch))
{
/* Most targets can step a breakpoint instruction, thus
executing it normally. But if this one cannot, just
continue and we will hit it anyway. */
if (step && breakpoint_inserted_here_p (pc))
step = 0;
}
if (debug_displaced
&& use_displaced_stepping (gdbarch)
&& tp->trap_expected)
{
struct regcache *resume_regcache = get_thread_regcache (resume_ptid);
CORE_ADDR actual_pc = regcache_read_pc (resume_regcache);
gdb_byte buf[4];
fprintf_unfiltered (gdb_stdlog, "displaced: run 0x%s: ",
paddr_nz (actual_pc));
read_memory (actual_pc, buf, sizeof (buf));
displaced_step_dump_bytes (gdb_stdlog, buf, sizeof (buf));
}
/* Avoid confusing the next resume, if the next stop/resume
happens to apply to another thread. */
tp->stop_signal = TARGET_SIGNAL_0;
target_resume (resume_ptid, step, sig);
}
discard_cleanups (old_cleanups);
}
/* Proceeding. */
/* Clear out all variables saying what to do when inferior is continued.
First do this, then set the ones you want, then call `proceed'. */
static void
clear_proceed_status_thread (struct thread_info *tp)
{
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog,
"infrun: clear_proceed_status_thread (%s)\n",
target_pid_to_str (tp->ptid));
tp->trap_expected = 0;
tp->step_range_start = 0;
tp->step_range_end = 0;
tp->step_frame_id = null_frame_id;
tp->step_over_calls = STEP_OVER_UNDEBUGGABLE;
tp->stop_requested = 0;
tp->stop_step = 0;
tp->proceed_to_finish = 0;
/* Discard any remaining commands or status from previous stop. */
bpstat_clear (&tp->stop_bpstat);
}
static int
clear_proceed_status_callback (struct thread_info *tp, void *data)
{
if (is_exited (tp->ptid))
return 0;
clear_proceed_status_thread (tp);
return 0;
}
void
clear_proceed_status (void)
{
if (!ptid_equal (inferior_ptid, null_ptid))
{
struct inferior *inferior;
if (non_stop)
{
/* If in non-stop mode, only delete the per-thread status
of the current thread. */
clear_proceed_status_thread (inferior_thread ());
}
else
{
/* In all-stop mode, delete the per-thread status of
*all* threads. */
iterate_over_threads (clear_proceed_status_callback, NULL);
}
inferior = current_inferior ();
inferior->stop_soon = NO_STOP_QUIETLY;
}
stop_after_trap = 0;
breakpoint_proceeded = 1; /* We're about to proceed... */
if (stop_registers)
{
regcache_xfree (stop_registers);
stop_registers = NULL;
}
}
/* This should be suitable for any targets that support threads. */
static int
prepare_to_proceed (int step)
{
ptid_t wait_ptid;
struct target_waitstatus wait_status;
/* Get the last target status returned by target_wait(). */
get_last_target_status (&wait_ptid, &wait_status);
/* Make sure we were stopped at a breakpoint. */
if (wait_status.kind != TARGET_WAITKIND_STOPPED
|| wait_status.value.sig != TARGET_SIGNAL_TRAP)
{
return 0;
}
/* Switched over from WAIT_PID. */
if (!ptid_equal (wait_ptid, minus_one_ptid)
&& !ptid_equal (inferior_ptid, wait_ptid))
{
struct regcache *regcache = get_thread_regcache (wait_ptid);
if (breakpoint_here_p (regcache_read_pc (regcache)))
{
/* If stepping, remember current thread to switch back to. */
if (step)
deferred_step_ptid = inferior_ptid;
/* Switch back to WAIT_PID thread. */
switch_to_thread (wait_ptid);
/* We return 1 to indicate that there is a breakpoint here,
so we need to step over it before continuing to avoid
hitting it straight away. */
return 1;
}
}
return 0;
}
/* Basic routine for continuing the program in various fashions.
ADDR is the address to resume at, or -1 for resume where stopped.
SIGGNAL is the signal to give it, or 0 for none,
or -1 for act according to how it stopped.
STEP is nonzero if should trap after one instruction.
-1 means return after that and print nothing.
You should probably set various step_... variables
before calling here, if you are stepping.
You should call clear_proceed_status before calling proceed. */
void
proceed (CORE_ADDR addr, enum target_signal siggnal, int step)
{
struct regcache *regcache = get_current_regcache ();
struct gdbarch *gdbarch = get_regcache_arch (regcache);
struct thread_info *tp;
CORE_ADDR pc = regcache_read_pc (regcache);
int oneproc = 0;
if (step > 0)
step_start_function = find_pc_function (pc);
if (step < 0)
stop_after_trap = 1;
if (addr == (CORE_ADDR) -1)
{
if (pc == stop_pc && breakpoint_here_p (pc)
&& execution_direction != EXEC_REVERSE)
/* There is a breakpoint at the address we will resume at,
step one instruction before inserting breakpoints so that
we do not stop right away (and report a second hit at this
breakpoint).
Note, we don't do this in reverse, because we won't
actually be executing the breakpoint insn anyway.
We'll be (un-)executing the previous instruction. */
oneproc = 1;
else if (gdbarch_single_step_through_delay_p (gdbarch)
&& gdbarch_single_step_through_delay (gdbarch,
get_current_frame ()))
/* We stepped onto an instruction that needs to be stepped
again before re-inserting the breakpoint, do so. */
oneproc = 1;
}
else
{
regcache_write_pc (regcache, addr);
}
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog,
"infrun: proceed (addr=0x%s, signal=%d, step=%d)\n",
paddr_nz (addr), siggnal, step);
if (non_stop)
/* In non-stop, each thread is handled individually. The context
must already be set to the right thread here. */
;
else
{
/* In a multi-threaded task we may select another thread and
then continue or step.
But if the old thread was stopped at a breakpoint, it will
immediately cause another breakpoint stop without any
execution (i.e. it will report a breakpoint hit incorrectly).
So we must step over it first.
prepare_to_proceed checks the current thread against the
thread that reported the most recent event. If a step-over
is required it returns TRUE and sets the current thread to
the old thread. */
if (prepare_to_proceed (step))
oneproc = 1;
}
/* prepare_to_proceed may change the current thread. */
tp = inferior_thread ();
if (oneproc)
{
tp->trap_expected = 1;
/* If displaced stepping is enabled, we can step over the
breakpoint without hitting it, so leave all breakpoints
inserted. Otherwise we need to disable all breakpoints, step
one instruction, and then re-add them when that step is
finished. */
if (!use_displaced_stepping (gdbarch))
remove_breakpoints ();
}
/* We can insert breakpoints if we're not trying to step over one,
or if we are stepping over one but we're using displaced stepping
to do so. */
if (! tp->trap_expected || use_displaced_stepping (gdbarch))
insert_breakpoints ();
if (!non_stop)
{
/* Pass the last stop signal to the thread we're resuming,
irrespective of whether the current thread is the thread that
got the last event or not. This was historically GDB's
behaviour before keeping a stop_signal per thread. */
struct thread_info *last_thread;
ptid_t last_ptid;
struct target_waitstatus last_status;
get_last_target_status (&last_ptid, &last_status);
if (!ptid_equal (inferior_ptid, last_ptid)
&& !ptid_equal (last_ptid, null_ptid)
&& !ptid_equal (last_ptid, minus_one_ptid))
{
last_thread = find_thread_pid (last_ptid);
if (last_thread)
{
tp->stop_signal = last_thread->stop_signal;
last_thread->stop_signal = TARGET_SIGNAL_0;
}
}
}
if (siggnal != TARGET_SIGNAL_DEFAULT)
tp->stop_signal = siggnal;
/* If this signal should not be seen by program,
give it zero. Used for debugging signals. */
else if (!signal_program[tp->stop_signal])
tp->stop_signal = TARGET_SIGNAL_0;
annotate_starting ();
/* Make sure that output from GDB appears before output from the
inferior. */
gdb_flush (gdb_stdout);
/* Refresh prev_pc value just prior to resuming. This used to be
done in stop_stepping, however, setting prev_pc there did not handle
scenarios such as inferior function calls or returning from
a function via the return command. In those cases, the prev_pc
value was not set properly for subsequent commands. The prev_pc value
is used to initialize the starting line number in the ecs. With an
invalid value, the gdb next command ends up stopping at the position
represented by the next line table entry past our start position.
On platforms that generate one line table entry per line, this
is not a problem. However, on the ia64, the compiler generates
extraneous line table entries that do not increase the line number.
When we issue the gdb next command on the ia64 after an inferior call
or a return command, we often end up a few instructions forward, still
within the original line we started.
An attempt was made to have init_execution_control_state () refresh
the prev_pc value before calculating the line number. This approach
did not work because on platforms that use ptrace, the pc register
cannot be read unless the inferior is stopped. At that point, we
are not guaranteed the inferior is stopped and so the regcache_read_pc ()
call can fail. Setting the prev_pc value here ensures the value is
updated correctly when the inferior is stopped. */
tp->prev_pc = regcache_read_pc (get_current_regcache ());
/* Fill in with reasonable starting values. */
init_thread_stepping_state (tp);
/* Reset to normal state. */
init_infwait_state ();
/* Resume inferior. */
resume (oneproc || step || bpstat_should_step (), tp->stop_signal);
/* Wait for it to stop (if not standalone)
and in any case decode why it stopped, and act accordingly. */
/* Do this only if we are not using the event loop, or if the target
does not support asynchronous execution. */
if (!target_can_async_p ())
{
wait_for_inferior (0);
normal_stop ();
}
}
/* Start remote-debugging of a machine over a serial link. */
void
start_remote (int from_tty)
{
struct inferior *inferior;
init_wait_for_inferior ();
inferior = current_inferior ();
inferior->stop_soon = STOP_QUIETLY_REMOTE;
/* Always go on waiting for the target, regardless of the mode. */
/* FIXME: cagney/1999-09-23: At present it isn't possible to
indicate to wait_for_inferior that a target should timeout if
nothing is returned (instead of just blocking). Because of this,
targets expecting an immediate response need to, internally, set
things up so that the target_wait() is forced to eventually
timeout. */
/* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
differentiate to its caller what the state of the target is after
the initial open has been performed. Here we're assuming that
the target has stopped. It should be possible to eventually have
target_open() return to the caller an indication that the target
is currently running and GDB state should be set to the same as
for an async run. */
wait_for_inferior (0);
/* Now that the inferior has stopped, do any bookkeeping like
loading shared libraries. We want to do this before normal_stop,
so that the displayed frame is up to date. */
post_create_inferior (¤t_target, from_tty);
normal_stop ();
}
/* Initialize static vars when a new inferior begins. */
void
init_wait_for_inferior (void)
{
/* These are meaningless until the first time through wait_for_inferior. */
breakpoint_init_inferior (inf_starting);
/* The first resume is not following a fork/vfork/exec. */
pending_follow.kind = TARGET_WAITKIND_SPURIOUS; /* I.e., none. */
clear_proceed_status ();
stepping_past_singlestep_breakpoint = 0;
deferred_step_ptid = null_ptid;
target_last_wait_ptid = minus_one_ptid;
previous_inferior_ptid = null_ptid;
init_infwait_state ();
displaced_step_clear ();
}
/* This enum encodes possible reasons for doing a target_wait, so that
wfi can call target_wait in one place. (Ultimately the call will be
moved out of the infinite loop entirely.) */
enum infwait_states
{
infwait_normal_state,
infwait_thread_hop_state,
infwait_step_watch_state,
infwait_nonstep_watch_state
};
/* Why did the inferior stop? Used to print the appropriate messages
to the interface from within handle_inferior_event(). */
enum inferior_stop_reason
{
/* Step, next, nexti, stepi finished. */
END_STEPPING_RANGE,
/* Inferior terminated by signal. */
SIGNAL_EXITED,
/* Inferior exited. */
EXITED,
/* Inferior received signal, and user asked to be notified. */
SIGNAL_RECEIVED,
/* Reverse execution -- target ran out of history info. */
NO_HISTORY
};
/* The PTID we'll do a target_wait on.*/
ptid_t waiton_ptid;
/* Current inferior wait state. */
enum infwait_states infwait_state;
/* Data to be passed around while handling an event. This data is
discarded between events. */
struct execution_control_state
{
ptid_t ptid;
/* The thread that got the event, if this was a thread event; NULL
otherwise. */
struct thread_info *event_thread;
struct target_waitstatus ws;
int random_signal;
CORE_ADDR stop_func_start;
CORE_ADDR stop_func_end;
char *stop_func_name;
int new_thread_event;
int wait_some_more;
};
void init_execution_control_state (struct execution_control_state *ecs);
void handle_inferior_event (struct execution_control_state *ecs);
static void handle_step_into_function (struct execution_control_state *ecs);
static void handle_step_into_function_backward (struct execution_control_state *ecs);
static void insert_step_resume_breakpoint_at_frame (struct frame_info *step_frame);
static void insert_step_resume_breakpoint_at_caller (struct frame_info *);
static void insert_step_resume_breakpoint_at_sal (struct symtab_and_line sr_sal,
struct frame_id sr_id);
static void insert_longjmp_resume_breakpoint (CORE_ADDR);
static void stop_stepping (struct execution_control_state *ecs);
static void prepare_to_wait (struct execution_control_state *ecs);
static void keep_going (struct execution_control_state *ecs);
static void print_stop_reason (enum inferior_stop_reason stop_reason,
int stop_info);
/* Callback for iterate over threads. If the thread is stopped, but
the user/frontend doesn't know about that yet, go through
normal_stop, as if the thread had just stopped now. ARG points at
a ptid. If PTID is MINUS_ONE_PTID, applies to all threads. If
ptid_is_pid(PTID) is true, applies to all threads of the process
pointed at by PTID. Otherwise, apply only to the thread pointed by
PTID. */
static int
infrun_thread_stop_requested_callback (struct thread_info *info, void *arg)
{
ptid_t ptid = * (ptid_t *) arg;
if ((ptid_equal (info->ptid, ptid)
|| ptid_equal (minus_one_ptid, ptid)
|| (ptid_is_pid (ptid)
&& ptid_get_pid (ptid) == ptid_get_pid (info->ptid)))
&& is_running (info->ptid)
&& !is_executing (info->ptid))
{
struct cleanup *old_chain;
struct execution_control_state ecss;
struct execution_control_state *ecs = &ecss;
memset (ecs, 0, sizeof (*ecs));
old_chain = make_cleanup_restore_current_thread ();
switch_to_thread (info->ptid);
/* Go through handle_inferior_event/normal_stop, so we always
have consistent output as if the stop event had been
reported. */
ecs->ptid = info->ptid;
ecs->event_thread = find_thread_pid (info->ptid);
ecs->ws.kind = TARGET_WAITKIND_STOPPED;
ecs->ws.value.sig = TARGET_SIGNAL_0;
handle_inferior_event (ecs);
if (!ecs->wait_some_more)
{
struct thread_info *tp;
normal_stop ();
/* Finish off the continuations. The continations
themselves are responsible for realising the thread
didn't finish what it was supposed to do. */
tp = inferior_thread ();
do_all_intermediate_continuations_thread (tp);
do_all_continuations_thread (tp);
}
do_cleanups (old_chain);
}
return 0;
}
/* This function is attached as a "thread_stop_requested" observer.
Cleanup local state that assumed the PTID was to be resumed, and
report the stop to the frontend. */
void
infrun_thread_stop_requested (ptid_t ptid)
{
struct displaced_step_request *it, *next, *prev = NULL;
/* PTID was requested to stop. Remove it from the displaced
stepping queue, so we don't try to resume it automatically. */
for (it = displaced_step_request_queue; it; it = next)
{
next = it->next;
if (ptid_equal (it->ptid, ptid)
|| ptid_equal (minus_one_ptid, ptid)
|| (ptid_is_pid (ptid)
&& ptid_get_pid (ptid) == ptid_get_pid (it->ptid)))
{
if (displaced_step_request_queue == it)
displaced_step_request_queue = it->next;
else
prev->next = it->next;
xfree (it);
}
else
prev = it;
}
iterate_over_threads (infrun_thread_stop_requested_callback, &ptid);
}
/* Callback for iterate_over_threads. */
static int
delete_step_resume_breakpoint_callback (struct thread_info *info, void *data)
{
if (is_exited (info->ptid))
return 0;
delete_step_resume_breakpoint (info);
return 0;
}
/* In all-stop, delete the step resume breakpoint of any thread that
had one. In non-stop, delete the step resume breakpoint of the
thread that just stopped. */
static void
delete_step_thread_step_resume_breakpoint (void)
{
if (!target_has_execution
|| ptid_equal (inferior_ptid, null_ptid))
/* If the inferior has exited, we have already deleted the step
resume breakpoints out of GDB's lists. */
return;
if (non_stop)
{
/* If in non-stop mode, only delete the step-resume or
longjmp-resume breakpoint of the thread that just stopped
stepping. */
struct thread_info *tp = inferior_thread ();
delete_step_resume_breakpoint (tp);
}
else
/* In all-stop mode, delete all step-resume and longjmp-resume
breakpoints of any thread that had them. */
iterate_over_threads (delete_step_resume_breakpoint_callback, NULL);
}
/* A cleanup wrapper. */
static void
delete_step_thread_step_resume_breakpoint_cleanup (void *arg)
{
delete_step_thread_step_resume_breakpoint ();
}
/* Wait for control to return from inferior to debugger.
If TREAT_EXEC_AS_SIGTRAP is non-zero, then handle EXEC signals
as if they were SIGTRAP signals. This can be useful during
the startup sequence on some targets such as HP/UX, where
we receive an EXEC event instead of the expected SIGTRAP.
If inferior gets a signal, we may decide to start it up again
instead of returning. That is why there is a loop in this function.
When this function actually returns it means the inferior
should be left stopped and GDB should read more commands. */
void
wait_for_inferior (int treat_exec_as_sigtrap)
{
struct cleanup *old_cleanups;
struct execution_control_state ecss;
struct execution_control_state *ecs;
if (debug_infrun)
fprintf_unfiltered
(gdb_stdlog, "infrun: wait_for_inferior (treat_exec_as_sigtrap=%d)\n",
treat_exec_as_sigtrap);
old_cleanups =
make_cleanup (delete_step_thread_step_resume_breakpoint_cleanup, NULL);
ecs = &ecss;
memset (ecs, 0, sizeof (*ecs));
overlay_cache_invalid = 1;
/* We'll update this if & when we switch to a new thread. */
previous_inferior_ptid = inferior_ptid;
/* We have to invalidate the registers BEFORE calling target_wait
because they can be loaded from the target while in target_wait.
This makes remote debugging a bit more efficient for those
targets that provide critical registers as part of their normal
status mechanism. */
registers_changed ();
while (1)
{
if (deprecated_target_wait_hook)
ecs->ptid = deprecated_target_wait_hook (waiton_ptid, &ecs->ws);
else
ecs->ptid = target_wait (waiton_ptid, &ecs->ws);
if (treat_exec_as_sigtrap && ecs->ws.kind == TARGET_WAITKIND_EXECD)
{
xfree (ecs->ws.value.execd_pathname);
ecs->ws.kind = TARGET_WAITKIND_STOPPED;
ecs->ws.value.sig = TARGET_SIGNAL_TRAP;
}
/* Now figure out what to do with the result of the result. */
handle_inferior_event (ecs);
if (!ecs->wait_some_more)
break;
}
do_cleanups (old_cleanups);
}
/* Asynchronous version of wait_for_inferior. It is called by the
event loop whenever a change of state is detected on the file
descriptor corresponding to the target. It can be called more than
once to complete a single execution command. In such cases we need
to keep the state in a global variable ECSS. If it is the last time
that this function is called for a single execution command, then
report to the user that the inferior has stopped, and do the
necessary cleanups. */
void
fetch_inferior_event (void *client_data)
{
struct execution_control_state ecss;
struct execution_control_state *ecs = &ecss;
struct cleanup *old_chain = make_cleanup (null_cleanup, NULL);
int was_sync = sync_execution;
memset (ecs, 0, sizeof (*ecs));
overlay_cache_invalid = 1;
/* We can only rely on wait_for_more being correct before handling
the event in all-stop, but previous_inferior_ptid isn't used in
non-stop. */
if (!ecs->wait_some_more)
/* We'll update this if & when we switch to a new thread. */
previous_inferior_ptid = inferior_ptid;
if (non_stop)
/* In non-stop mode, the user/frontend should not notice a thread
switch due to internal events. Make sure we reverse to the
user selected thread and frame after handling the event and
running any breakpoint commands. */
make_cleanup_restore_current_thread ();
/* We have to invalidate the registers BEFORE calling target_wait
because they can be loaded from the target while in target_wait.
This makes remote debugging a bit more efficient for those
targets that provide critical registers as part of their normal
status mechanism. */
registers_changed ();
if (deprecated_target_wait_hook)
ecs->ptid =
deprecated_target_wait_hook (waiton_ptid, &ecs->ws);
else
ecs->ptid = target_wait (waiton_ptid, &ecs->ws);
if (non_stop
&& ecs->ws.kind != TARGET_WAITKIND_IGNORE
&& ecs->ws.kind != TARGET_WAITKIND_EXITED
&& ecs->ws.kind != TARGET_WAITKIND_SIGNALLED)
/* In non-stop mode, each thread is handled individually. Switch
early, so the global state is set correctly for this
thread. */
context_switch (ecs->ptid);
/* Now figure out what to do with the result of the result. */
handle_inferior_event (ecs);
if (!ecs->wait_some_more)
{
struct inferior *inf = find_inferior_pid (ptid_get_pid (ecs->ptid));
delete_step_thread_step_resume_breakpoint ();
/* We may not find an inferior if this was a process exit. */
if (inf == NULL || inf->stop_soon == NO_STOP_QUIETLY)
normal_stop ();
if (target_has_execution
&& ecs->ws.kind != TARGET_WAITKIND_EXITED
&& ecs->ws.kind != TARGET_WAITKIND_SIGNALLED
&& ecs->event_thread->step_multi
&& ecs->event_thread->stop_step)
inferior_event_handler (INF_EXEC_CONTINUE, NULL);
else
inferior_event_handler (INF_EXEC_COMPLETE, NULL);
}
/* Revert thread and frame. */
do_cleanups (old_chain);
/* If the inferior was in sync execution mode, and now isn't,
restore the prompt. */
if (was_sync && !sync_execution)
display_gdb_prompt (0);
}
/* Prepare an execution control state for looping through a
wait_for_inferior-type loop. */
void
init_execution_control_state (struct execution_control_state *ecs)
{
ecs->random_signal = 0;
}
/* Clear context switchable stepping state. */
void
init_thread_stepping_state (struct thread_info *tss)
{
struct symtab_and_line sal;
tss->stepping_over_breakpoint = 0;
tss->step_after_step_resume_breakpoint = 0;
tss->stepping_through_solib_after_catch = 0;
tss->stepping_through_solib_catchpoints = NULL;
sal = find_pc_line (tss->prev_pc, 0);
tss->current_line = sal.line;
tss->current_symtab = sal.symtab;
}
/* Return the cached copy of the last pid/waitstatus returned by
target_wait()/deprecated_target_wait_hook(). The data is actually
cached by handle_inferior_event(), which gets called immediately
after target_wait()/deprecated_target_wait_hook(). */
void
get_last_target_status (ptid_t *ptidp, struct target_waitstatus *status)
{
*ptidp = target_last_wait_ptid;
*status = target_last_waitstatus;
}
void
nullify_last_target_wait_ptid (void)
{
target_last_wait_ptid = minus_one_ptid;
}
/* Switch thread contexts. */
static void
context_switch (ptid_t ptid)
{
if (debug_infrun)
{
fprintf_unfiltered (gdb_stdlog, "infrun: Switching context from %s ",
target_pid_to_str (inferior_ptid));
fprintf_unfiltered (gdb_stdlog, "to %s\n",
target_pid_to_str (ptid));
}
switch_to_thread (ptid);
}
static void
adjust_pc_after_break (struct execution_control_state *ecs)
{
struct regcache *regcache;
struct gdbarch *gdbarch;
CORE_ADDR breakpoint_pc;
/* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
we aren't, just return.
We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
affected by gdbarch_decr_pc_after_break. Other waitkinds which are
implemented by software breakpoints should be handled through the normal
breakpoint layer.
NOTE drow/2004-01-31: On some targets, breakpoints may generate
different signals (SIGILL or SIGEMT for instance), but it is less
clear where the PC is pointing afterwards. It may not match
gdbarch_decr_pc_after_break. I don't know any specific target that
generates these signals at breakpoints (the code has been in GDB since at
least 1992) so I can not guess how to handle them here.
In earlier versions of GDB, a target with
gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
target with both of these set in GDB history, and it seems unlikely to be
correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
if (ecs->ws.kind != TARGET_WAITKIND_STOPPED)
return;
if (ecs->ws.value.sig != TARGET_SIGNAL_TRAP)
return;
/* In reverse execution, when a breakpoint is hit, the instruction
under it has already been de-executed. The reported PC always
points at the breakpoint address, so adjusting it further would
be wrong. E.g., consider this case on a decr_pc_after_break == 1
architecture:
B1 0x08000000 : INSN1
B2 0x08000001 : INSN2
0x08000002 : INSN3
PC -> 0x08000003 : INSN4
Say you're stopped at 0x08000003 as above. Reverse continuing
from that point should hit B2 as below. Reading the PC when the
SIGTRAP is reported should read 0x08000001 and INSN2 should have
been de-executed already.
B1 0x08000000 : INSN1
B2 PC -> 0x08000001 : INSN2
0x08000002 : INSN3
0x08000003 : INSN4
We can't apply the same logic as for forward execution, because
we would wrongly adjust the PC to 0x08000000, since there's a
breakpoint at PC - 1. We'd then report a hit on B1, although
INSN1 hadn't been de-executed yet. Doing nothing is the correct
behaviour. */
if (execution_direction == EXEC_REVERSE)
return;
/* If this target does not decrement the PC after breakpoints, then
we have nothing to do. */
regcache = get_thread_regcache (ecs->ptid);
gdbarch = get_regcache_arch (regcache);
if (gdbarch_decr_pc_after_break (gdbarch) == 0)
return;
/* Find the location where (if we've hit a breakpoint) the
breakpoint would be. */
breakpoint_pc = regcache_read_pc (regcache)
- gdbarch_decr_pc_after_break (gdbarch);
/* Check whether there actually is a software breakpoint inserted at
that location.
If in non-stop mode, a race condition is possible where we've
removed a breakpoint, but stop events for that breakpoint were
already queued and arrive later. To suppress those spurious
SIGTRAPs, we keep a list of such breakpoint locations for a bit,
and retire them after a number of stop events are reported. */
if (software_breakpoint_inserted_here_p (breakpoint_pc)
|| (non_stop && moribund_breakpoint_here_p (breakpoint_pc)))
{
/* When using hardware single-step, a SIGTRAP is reported for both
a completed single-step and a software breakpoint. Need to
differentiate between the two, as the latter needs adjusting
but the former does not.
The SIGTRAP can be due to a completed hardware single-step only if
- we didn't insert software single-step breakpoints
- the thread to be examined is still the current thread
- this thread is currently being stepped
If any of these events did not occur, we must have stopped due
to hitting a software breakpoint, and have to back up to the
breakpoint address.
As a special case, we could have hardware single-stepped a
software breakpoint. In this case (prev_pc == breakpoint_pc),
we also need to back up to the breakpoint address. */
if (singlestep_breakpoints_inserted_p
|| !ptid_equal (ecs->ptid, inferior_ptid)
|| !currently_stepping (ecs->event_thread)
|| ecs->event_thread->prev_pc == breakpoint_pc)
regcache_write_pc (regcache, breakpoint_pc);
}
}
void
init_infwait_state (void)
{
waiton_ptid = pid_to_ptid (-1);
infwait_state = infwait_normal_state;
}
void
error_is_running (void)
{
error (_("\
Cannot execute this command while the selected thread is running."));
}
void
ensure_not_running (void)
{
if (is_running (inferior_ptid))
error_is_running ();
}
/* Given an execution control state that has been freshly filled in
by an event from the inferior, figure out what it means and take
appropriate action. */
void
handle_inferior_event (struct execution_control_state *ecs)
{
int sw_single_step_trap_p = 0;
int stopped_by_watchpoint;
int stepped_after_stopped_by_watchpoint = 0;
struct symtab_and_line stop_pc_sal;
enum stop_kind stop_soon;
if (ecs->ws.kind != TARGET_WAITKIND_EXITED
&& ecs->ws.kind != TARGET_WAITKIND_SIGNALLED
&& ecs->ws.kind != TARGET_WAITKIND_IGNORE)
{
struct inferior *inf = find_inferior_pid (ptid_get_pid (ecs->ptid));
gdb_assert (inf);
stop_soon = inf->stop_soon;
}
else
stop_soon = NO_STOP_QUIETLY;
/* Cache the last pid/waitstatus. */
target_last_wait_ptid = ecs->ptid;
target_last_waitstatus = ecs->ws;
/* Always clear state belonging to the previous time we stopped. */
stop_stack_dummy = 0;
/* If it's a new process, add it to the thread database */
ecs->new_thread_event = (!ptid_equal (ecs->ptid, inferior_ptid)
&& !ptid_equal (ecs->ptid, minus_one_ptid)
&& !in_thread_list (ecs->ptid));
if (ecs->ws.kind != TARGET_WAITKIND_EXITED
&& ecs->ws.kind != TARGET_WAITKIND_SIGNALLED && ecs->new_thread_event)
add_thread (ecs->ptid);
ecs->event_thread = find_thread_pid (ecs->ptid);
/* Dependent on valid ECS->EVENT_THREAD. */
adjust_pc_after_break (ecs);
/* Dependent on the current PC value modified by adjust_pc_after_break. */
reinit_frame_cache ();
if (ecs->ws.kind != TARGET_WAITKIND_IGNORE)
{
breakpoint_retire_moribund ();
/* Mark the non-executing threads accordingly. In all-stop, all
threads of all processes are stopped when we get any event
reported. In non-stop mode, only the event thread stops. If
we're handling a process exit in non-stop mode, there's
nothing to do, as threads of the dead process are gone, and
threads of any other process were left running. */
if (!non_stop)
set_executing (minus_one_ptid, 0);
else if (ecs->ws.kind != TARGET_WAITKIND_SIGNALLED
&& ecs->ws.kind != TARGET_WAITKIND_EXITED)
set_executing (inferior_ptid, 0);
}
switch (infwait_state)
{
case infwait_thread_hop_state:
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: infwait_thread_hop_state\n");
/* Cancel the waiton_ptid. */
waiton_ptid = pid_to_ptid (-1);
break;
case infwait_normal_state:
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: infwait_normal_state\n");
break;
case infwait_step_watch_state:
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog,
"infrun: infwait_step_watch_state\n");
stepped_after_stopped_by_watchpoint = 1;
break;
case infwait_nonstep_watch_state:
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog,
"infrun: infwait_nonstep_watch_state\n");
insert_breakpoints ();
/* FIXME-maybe: is this cleaner than setting a flag? Does it
handle things like signals arriving and other things happening
in combination correctly? */
stepped_after_stopped_by_watchpoint = 1;
break;
default:
internal_error (__FILE__, __LINE__, _("bad switch"));
}
infwait_state = infwait_normal_state;
switch (ecs->ws.kind)
{
case TARGET_WAITKIND_LOADED:
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_LOADED\n");
/* Ignore gracefully during startup of the inferior, as it might
be the shell which has just loaded some objects, otherwise
add the symbols for the newly loaded objects. Also ignore at
the beginning of an attach or remote session; we will query
the full list of libraries once the connection is
established. */
if (stop_soon == NO_STOP_QUIETLY)
{
/* Check for any newly added shared libraries if we're
supposed to be adding them automatically. Switch
terminal for any messages produced by
breakpoint_re_set. */
target_terminal_ours_for_output ();
/* NOTE: cagney/2003-11-25: Make certain that the target
stack's section table is kept up-to-date. Architectures,
(e.g., PPC64), use the section table to perform
operations such as address => section name and hence
require the table to contain all sections (including
those found in shared libraries). */
/* NOTE: cagney/2003-11-25: Pass current_target and not
exec_ops to SOLIB_ADD. This is because current GDB is
only tooled to propagate section_table changes out from
the "current_target" (see target_resize_to_sections), and
not up from the exec stratum. This, of course, isn't
right. "infrun.c" should only interact with the
exec/process stratum, instead relying on the target stack
to propagate relevant changes (stop, section table
changed, ...) up to other layers. */
#ifdef SOLIB_ADD
SOLIB_ADD (NULL, 0, ¤t_target, auto_solib_add);
#else
solib_add (NULL, 0, ¤t_target, auto_solib_add);
#endif
target_terminal_inferior ();
/* If requested, stop when the dynamic linker notifies
gdb of events. This allows the user to get control
and place breakpoints in initializer routines for
dynamically loaded objects (among other things). */
if (stop_on_solib_events)
{
stop_stepping (ecs);
return;
}
/* NOTE drow/2007-05-11: This might be a good place to check
for "catch load". */
}
/* If we are skipping through a shell, or through shared library
loading that we aren't interested in, resume the program. If
we're running the program normally, also resume. But stop if
we're attaching or setting up a remote connection. */
if (stop_soon == STOP_QUIETLY || stop_soon == NO_STOP_QUIETLY)
{
/* Loading of shared libraries might have changed breakpoint
addresses. Make sure new breakpoints are inserted. */
if (stop_soon == NO_STOP_QUIETLY
&& !breakpoints_always_inserted_mode ())
insert_breakpoints ();
resume (0, TARGET_SIGNAL_0);
prepare_to_wait (ecs);
return;
}
break;
case TARGET_WAITKIND_SPURIOUS:
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_SPURIOUS\n");
resume (0, TARGET_SIGNAL_0);
prepare_to_wait (ecs);
return;
case TARGET_WAITKIND_EXITED:
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_EXITED\n");
inferior_ptid = ecs->ptid;
target_terminal_ours (); /* Must do this before mourn anyway */
print_stop_reason (EXITED, ecs->ws.value.integer);
/* Record the exit code in the convenience variable $_exitcode, so
that the user can inspect this again later. */
set_internalvar (lookup_internalvar ("_exitcode"),
value_from_longest (builtin_type_int32,
(LONGEST) ecs->ws.value.integer));
gdb_flush (gdb_stdout);
target_mourn_inferior ();
singlestep_breakpoints_inserted_p = 0;
stop_print_frame = 0;
stop_stepping (ecs);
return;
case TARGET_WAITKIND_SIGNALLED:
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_SIGNALLED\n");
inferior_ptid = ecs->ptid;
stop_print_frame = 0;
target_terminal_ours (); /* Must do this before mourn anyway */
/* Note: By definition of TARGET_WAITKIND_SIGNALLED, we shouldn't
reach here unless the inferior is dead. However, for years
target_kill() was called here, which hints that fatal signals aren't
really fatal on some systems. If that's true, then some changes
may be needed. */
target_mourn_inferior ();
print_stop_reason (SIGNAL_EXITED, ecs->ws.value.sig);
singlestep_breakpoints_inserted_p = 0;
stop_stepping (ecs);
return;
/* The following are the only cases in which we keep going;
the above cases end in a continue or goto. */
case TARGET_WAITKIND_FORKED:
case TARGET_WAITKIND_VFORKED:
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_FORKED\n");
pending_follow.kind = ecs->ws.kind;
pending_follow.fork_event.parent_pid = ecs->ptid;
pending_follow.fork_event.child_pid = ecs->ws.value.related_pid;
if (!ptid_equal (ecs->ptid, inferior_ptid))
{
context_switch (ecs->ptid);
reinit_frame_cache ();
}
stop_pc = read_pc ();
ecs->event_thread->stop_bpstat = bpstat_stop_status (stop_pc, ecs->ptid);
ecs->random_signal = !bpstat_explains_signal (ecs->event_thread->stop_bpstat);
/* If no catchpoint triggered for this, then keep going. */
if (ecs->random_signal)
{
ecs->event_thread->stop_signal = TARGET_SIGNAL_0;
keep_going (ecs);
return;
}
ecs->event_thread->stop_signal = TARGET_SIGNAL_TRAP;
goto process_event_stop_test;
case TARGET_WAITKIND_EXECD:
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_EXECD\n");
pending_follow.execd_pathname =
savestring (ecs->ws.value.execd_pathname,
strlen (ecs->ws.value.execd_pathname));
if (!ptid_equal (ecs->ptid, inferior_ptid))
{
context_switch (ecs->ptid);
reinit_frame_cache ();
}
stop_pc = read_pc ();
/* This causes the eventpoints and symbol table to be reset.
Must do this now, before trying to determine whether to
stop. */
follow_exec (inferior_ptid, pending_follow.execd_pathname);
xfree (pending_follow.execd_pathname);
ecs->event_thread->stop_bpstat = bpstat_stop_status (stop_pc, ecs->ptid);
ecs->random_signal = !bpstat_explains_signal (ecs->event_thread->stop_bpstat);
/* If no catchpoint triggered for this, then keep going. */
if (ecs->random_signal)
{
ecs->event_thread->stop_signal = TARGET_SIGNAL_0;
keep_going (ecs);
return;
}
ecs->event_thread->stop_signal = TARGET_SIGNAL_TRAP;
goto process_event_stop_test;
/* Be careful not to try to gather much state about a thread
that's in a syscall. It's frequently a losing proposition. */
case TARGET_WAITKIND_SYSCALL_ENTRY:
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
resume (0, TARGET_SIGNAL_0);
prepare_to_wait (ecs);
return;
/* Before examining the threads further, step this thread to
get it entirely out of the syscall. (We get notice of the
event when the thread is just on the verge of exiting a
syscall. Stepping one instruction seems to get it back
into user code.) */
case TARGET_WAITKIND_SYSCALL_RETURN:
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
target_resume (ecs->ptid, 1, TARGET_SIGNAL_0);
prepare_to_wait (ecs);
return;
case TARGET_WAITKIND_STOPPED:
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_STOPPED\n");
ecs->event_thread->stop_signal = ecs->ws.value.sig;
break;
case TARGET_WAITKIND_NO_HISTORY:
/* Reverse execution: target ran out of history info. */
stop_pc = read_pc ();
print_stop_reason (NO_HISTORY, 0);
stop_stepping (ecs);
return;
/* We had an event in the inferior, but we are not interested
in handling it at this level. The lower layers have already
done what needs to be done, if anything.
One of the possible circumstances for this is when the
inferior produces output for the console. The inferior has
not stopped, and we are ignoring the event. Another possible
circumstance is any event which the lower level knows will be
reported multiple times without an intervening resume. */
case TARGET_WAITKIND_IGNORE:
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_IGNORE\n");
prepare_to_wait (ecs);
return;
}
if (ecs->new_thread_event)
{
if (non_stop)
/* Non-stop assumes that the target handles adding new threads
to the thread list. */
internal_error (__FILE__, __LINE__, "\
targets should add new threads to the thread list themselves in non-stop mode.");
/* We may want to consider not doing a resume here in order to
give the user a chance to play with the new thread. It might
be good to make that a user-settable option. */
/* At this point, all threads are stopped (happens automatically
in either the OS or the native code). Therefore we need to
continue all threads in order to make progress. */
target_resume (RESUME_ALL, 0, TARGET_SIGNAL_0);
prepare_to_wait (ecs);
return;
}
if (ecs->ws.kind == TARGET_WAITKIND_STOPPED)
{
/* Do we need to clean up the state of a thread that has
completed a displaced single-step? (Doing so usually affects
the PC, so do it here, before we set stop_pc.) */
displaced_step_fixup (ecs->ptid, ecs->event_thread->stop_signal);
/* If we either finished a single-step or hit a breakpoint, but
the user wanted this thread to be stopped, pretend we got a
SIG0 (generic unsignaled stop). */
if (ecs->event_thread->stop_requested
&& ecs->event_thread->stop_signal == TARGET_SIGNAL_TRAP)
ecs->event_thread->stop_signal = TARGET_SIGNAL_0;
}
stop_pc = regcache_read_pc (get_thread_regcache (ecs->ptid));
if (debug_infrun)
{
fprintf_unfiltered (gdb_stdlog, "infrun: stop_pc = 0x%s\n",
paddr_nz (stop_pc));
if (STOPPED_BY_WATCHPOINT (&ecs->ws))
{
CORE_ADDR addr;
fprintf_unfiltered (gdb_stdlog, "infrun: stopped by watchpoint\n");
if (target_stopped_data_address (¤t_target, &addr))
fprintf_unfiltered (gdb_stdlog,
"infrun: stopped data address = 0x%s\n",
paddr_nz (addr));
else
fprintf_unfiltered (gdb_stdlog,
"infrun: (no data address available)\n");
}
}
if (stepping_past_singlestep_breakpoint)
{
gdb_assert (singlestep_breakpoints_inserted_p);
gdb_assert (ptid_equal (singlestep_ptid, ecs->ptid));
gdb_assert (!ptid_equal (singlestep_ptid, saved_singlestep_ptid));
stepping_past_singlestep_breakpoint = 0;
/* We've either finished single-stepping past the single-step
breakpoint, or stopped for some other reason. It would be nice if
we could tell, but we can't reliably. */
if (ecs->event_thread->stop_signal == TARGET_SIGNAL_TRAP)
{
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: stepping_past_singlestep_breakpoint\n");
/* Pull the single step breakpoints out of the target. */
remove_single_step_breakpoints ();
singlestep_breakpoints_inserted_p = 0;
ecs->random_signal = 0;
context_switch (saved_singlestep_ptid);
if (deprecated_context_hook)
deprecated_context_hook (pid_to_thread_id (ecs->ptid));
resume (1, TARGET_SIGNAL_0);
prepare_to_wait (ecs);
return;
}
}
if (!ptid_equal (deferred_step_ptid, null_ptid))
{
/* In non-stop mode, there's never a deferred_step_ptid set. */
gdb_assert (!non_stop);
/* If we stopped for some other reason than single-stepping, ignore
the fact that we were supposed to switch back. */
if (ecs->event_thread->stop_signal == TARGET_SIGNAL_TRAP)
{
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog,
"infrun: handling deferred step\n");
/* Pull the single step breakpoints out of the target. */
if (singlestep_breakpoints_inserted_p)
{
remove_single_step_breakpoints ();
singlestep_breakpoints_inserted_p = 0;
}
/* Note: We do not call context_switch at this point, as the
context is already set up for stepping the original thread. */
switch_to_thread (deferred_step_ptid);
deferred_step_ptid = null_ptid;
/* Suppress spurious "Switching to ..." message. */
previous_inferior_ptid = inferior_ptid;
resume (1, TARGET_SIGNAL_0);
prepare_to_wait (ecs);
return;
}
deferred_step_ptid = null_ptid;
}
/* See if a thread hit a thread-specific breakpoint that was meant for
another thread. If so, then step that thread past the breakpoint,
and continue it. */
if (ecs->event_thread->stop_signal == TARGET_SIGNAL_TRAP)
{
int thread_hop_needed = 0;
/* Check if a regular breakpoint has been hit before checking
for a potential single step breakpoint. Otherwise, GDB will
not see this breakpoint hit when stepping onto breakpoints. */
if (regular_breakpoint_inserted_here_p (stop_pc))
{
ecs->random_signal = 0;
if (!breakpoint_thread_match (stop_pc, ecs->ptid))
thread_hop_needed = 1;
}
else if (singlestep_breakpoints_inserted_p)
{
/* We have not context switched yet, so this should be true
no matter which thread hit the singlestep breakpoint. */
gdb_assert (ptid_equal (inferior_ptid, singlestep_ptid));
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: software single step "
"trap for %s\n",
target_pid_to_str (ecs->ptid));
ecs->random_signal = 0;
/* The call to in_thread_list is necessary because PTIDs sometimes
change when we go from single-threaded to multi-threaded. If
the singlestep_ptid is still in the list, assume that it is
really different from ecs->ptid. */
if (!ptid_equal (singlestep_ptid, ecs->ptid)
&& in_thread_list (singlestep_ptid))
{
/* If the PC of the thread we were trying to single-step
has changed, discard this event (which we were going
to ignore anyway), and pretend we saw that thread
trap. This prevents us continuously moving the
single-step breakpoint forward, one instruction at a
time. If the PC has changed, then the thread we were
trying to single-step has trapped or been signalled,
but the event has not been reported to GDB yet.
There might be some cases where this loses signal
information, if a signal has arrived at exactly the
same time that the PC changed, but this is the best
we can do with the information available. Perhaps we
should arrange to report all events for all threads
when they stop, or to re-poll the remote looking for
this particular thread (i.e. temporarily enable
schedlock). */
CORE_ADDR new_singlestep_pc
= regcache_read_pc (get_thread_regcache (singlestep_ptid));
if (new_singlestep_pc != singlestep_pc)
{
enum target_signal stop_signal;
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: unexpected thread,"
" but expected thread advanced also\n");
/* The current context still belongs to
singlestep_ptid. Don't swap here, since that's
the context we want to use. Just fudge our
state and continue. */
stop_signal = ecs->event_thread->stop_signal;
ecs->event_thread->stop_signal = TARGET_SIGNAL_0;
ecs->ptid = singlestep_ptid;
ecs->event_thread = find_thread_pid (ecs->ptid);
ecs->event_thread->stop_signal = stop_signal;
stop_pc = new_singlestep_pc;
}
else
{
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog,
"infrun: unexpected thread\n");
thread_hop_needed = 1;
stepping_past_singlestep_breakpoint = 1;
saved_singlestep_ptid = singlestep_ptid;
}
}
}
if (thread_hop_needed)
{
int remove_status = 0;
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: thread_hop_needed\n");
/* Saw a breakpoint, but it was hit by the wrong thread.
Just continue. */
if (singlestep_breakpoints_inserted_p)
{
/* Pull the single step breakpoints out of the target. */
remove_single_step_breakpoints ();
singlestep_breakpoints_inserted_p = 0;
}
/* If the arch can displace step, don't remove the
breakpoints. */
if (!use_displaced_stepping (current_gdbarch))
remove_status = remove_breakpoints ();
/* Did we fail to remove breakpoints? If so, try
to set the PC past the bp. (There's at least
one situation in which we can fail to remove
the bp's: On HP-UX's that use ttrace, we can't
change the address space of a vforking child
process until the child exits (well, okay, not
then either :-) or execs. */
if (remove_status != 0)
error (_("Cannot step over breakpoint hit in wrong thread"));
else
{ /* Single step */
if (!ptid_equal (inferior_ptid, ecs->ptid))
context_switch (ecs->ptid);
if (!non_stop)
{
/* Only need to require the next event from this
thread in all-stop mode. */
waiton_ptid = ecs->ptid;
infwait_state = infwait_thread_hop_state;
}
ecs->event_thread->stepping_over_breakpoint = 1;
keep_going (ecs);
registers_changed ();
return;
}
}
else if (singlestep_breakpoints_inserted_p)
{
sw_single_step_trap_p = 1;
ecs->random_signal = 0;
}
}
else
ecs->random_signal = 1;
/* See if something interesting happened to the non-current thread. If
so, then switch to that thread. */
if (!ptid_equal (ecs->ptid, inferior_ptid))
{
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: context switch\n");
context_switch (ecs->ptid);
if (deprecated_context_hook)
deprecated_context_hook (pid_to_thread_id (ecs->ptid));
}
if (singlestep_breakpoints_inserted_p)
{
/* Pull the single step breakpoints out of the target. */
remove_single_step_breakpoints ();
singlestep_breakpoints_inserted_p = 0;
}
if (stepped_after_stopped_by_watchpoint)
stopped_by_watchpoint = 0;
else
stopped_by_watchpoint = watchpoints_triggered (&ecs->ws);
/* If necessary, step over this watchpoint. We'll be back to display
it in a moment. */
if (stopped_by_watchpoint
&& (HAVE_STEPPABLE_WATCHPOINT
|| gdbarch_have_nonsteppable_watchpoint (current_gdbarch)))
{
/* At this point, we are stopped at an instruction which has
attempted to write to a piece of memory under control of
a watchpoint. The instruction hasn't actually executed
yet. If we were to evaluate the watchpoint expression
now, we would get the old value, and therefore no change
would seem to have occurred.
In order to make watchpoints work `right', we really need
to complete the memory write, and then evaluate the
watchpoint expression. We do this by single-stepping the
target.
It may not be necessary to disable the watchpoint to stop over
it. For example, the PA can (with some kernel cooperation)
single step over a watchpoint without disabling the watchpoint.
It is far more common to need to disable a watchpoint to step
the inferior over it. If we have non-steppable watchpoints,
we must disable the current watchpoint; it's simplest to
disable all watchpoints and breakpoints. */
if (!HAVE_STEPPABLE_WATCHPOINT)
remove_breakpoints ();
registers_changed ();
target_resume (ecs->ptid, 1, TARGET_SIGNAL_0); /* Single step */
waiton_ptid = ecs->ptid;
if (HAVE_STEPPABLE_WATCHPOINT)
infwait_state = infwait_step_watch_state;
else
infwait_state = infwait_nonstep_watch_state;
prepare_to_wait (ecs);
return;
}
ecs->stop_func_start = 0;
ecs->stop_func_end = 0;
ecs->stop_func_name = 0;
/* Don't care about return value; stop_func_start and stop_func_name
will both be 0 if it doesn't work. */
find_pc_partial_function (stop_pc, &ecs->stop_func_name,
&ecs->stop_func_start, &ecs->stop_func_end);
ecs->stop_func_start
+= gdbarch_deprecated_function_start_offset (current_gdbarch);
ecs->event_thread->stepping_over_breakpoint = 0;
bpstat_clear (&ecs->event_thread->stop_bpstat);
ecs->event_thread->stop_step = 0;
stop_print_frame = 1;
ecs->random_signal = 0;
stopped_by_random_signal = 0;
if (ecs->event_thread->stop_signal == TARGET_SIGNAL_TRAP
&& ecs->event_thread->trap_expected
&& gdbarch_single_step_through_delay_p (current_gdbarch)
&& currently_stepping (ecs->event_thread))
{
/* We're trying to step off a breakpoint. Turns out that we're
also on an instruction that needs to be stepped multiple
times before it's been fully executing. E.g., architectures
with a delay slot. It needs to be stepped twice, once for
the instruction and once for the delay slot. */
int step_through_delay
= gdbarch_single_step_through_delay (current_gdbarch,
get_current_frame ());
if (debug_infrun && step_through_delay)
fprintf_unfiltered (gdb_stdlog, "infrun: step through delay\n");
if (ecs->event_thread->step_range_end == 0 && step_through_delay)
{
/* The user issued a continue when stopped at a breakpoint.
Set up for another trap and get out of here. */
ecs->event_thread->stepping_over_breakpoint = 1;
keep_going (ecs);
return;
}
else if (step_through_delay)
{
/* The user issued a step when stopped at a breakpoint.
Maybe we should stop, maybe we should not - the delay
slot *might* correspond to a line of source. In any
case, don't decide that here, just set
ecs->stepping_over_breakpoint, making sure we
single-step again before breakpoints are re-inserted. */
ecs->event_thread->stepping_over_breakpoint = 1;
}
}
/* Look at the cause of the stop, and decide what to do.
The alternatives are:
1) stop_stepping and return; to really stop and return to the debugger,
2) keep_going and return to start up again
(set ecs->event_thread->stepping_over_breakpoint to 1 to single step once)
3) set ecs->random_signal to 1, and the decision between 1 and 2
will be made according to the signal handling tables. */
/* First, distinguish signals caused by the debugger from signals
that have to do with the program's own actions. Note that
breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
on the operating system version. Here we detect when a SIGILL or
SIGEMT is really a breakpoint and change it to SIGTRAP. We do
something similar for SIGSEGV, since a SIGSEGV will be generated
when we're trying to execute a breakpoint instruction on a
non-executable stack. This happens for call dummy breakpoints
for architectures like SPARC that place call dummies on the
stack.
If we're doing a displaced step past a breakpoint, then the
breakpoint is always inserted at the original instruction;
non-standard signals can't be explained by the breakpoint. */
if (ecs->event_thread->stop_signal == TARGET_SIGNAL_TRAP
|| (! ecs->event_thread->trap_expected
&& breakpoint_inserted_here_p (stop_pc)
&& (ecs->event_thread->stop_signal == TARGET_SIGNAL_ILL
|| ecs->event_thread->stop_signal == TARGET_SIGNAL_SEGV
|| ecs->event_thread->stop_signal == TARGET_SIGNAL_EMT))
|| stop_soon == STOP_QUIETLY || stop_soon == STOP_QUIETLY_NO_SIGSTOP
|| stop_soon == STOP_QUIETLY_REMOTE)
{
if (ecs->event_thread->stop_signal == TARGET_SIGNAL_TRAP && stop_after_trap)
{
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: stopped\n");
stop_print_frame = 0;
stop_stepping (ecs);
return;
}
/* This is originated from start_remote(), start_inferior() and
shared libraries hook functions. */
if (stop_soon == STOP_QUIETLY || stop_soon == STOP_QUIETLY_REMOTE)
{
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: quietly stopped\n");
stop_stepping (ecs);
return;
}
/* This originates from attach_command(). We need to overwrite
the stop_signal here, because some kernels don't ignore a
SIGSTOP in a subsequent ptrace(PTRACE_CONT,SIGSTOP) call.
See more comments in inferior.h. On the other hand, if we
get a non-SIGSTOP, report it to the user - assume the backend
will handle the SIGSTOP if it should show up later.
Also consider that the attach is complete when we see a
SIGTRAP. Some systems (e.g. Windows), and stubs supporting
target extended-remote report it instead of a SIGSTOP
(e.g. gdbserver). We already rely on SIGTRAP being our
signal, so this is no exception.
Also consider that the attach is complete when we see a
TARGET_SIGNAL_0. In non-stop mode, GDB will explicitly tell
the target to stop all threads of the inferior, in case the
low level attach operation doesn't stop them implicitly. If
they weren't stopped implicitly, then the stub will report a
TARGET_SIGNAL_0, meaning: stopped for no particular reason
other than GDB's request. */
if (stop_soon == STOP_QUIETLY_NO_SIGSTOP
&& (ecs->event_thread->stop_signal == TARGET_SIGNAL_STOP
|| ecs->event_thread->stop_signal == TARGET_SIGNAL_TRAP
|| ecs->event_thread->stop_signal == TARGET_SIGNAL_0))
{
stop_stepping (ecs);
ecs->event_thread->stop_signal = TARGET_SIGNAL_0;
return;
}
/* See if there is a breakpoint at the current PC. */
ecs->event_thread->stop_bpstat = bpstat_stop_status (stop_pc, ecs->ptid);
/* Following in case break condition called a
function. */
stop_print_frame = 1;
/* NOTE: cagney/2003-03-29: These two checks for a random signal
at one stage in the past included checks for an inferior
function call's call dummy's return breakpoint. The original
comment, that went with the test, read:
``End of a stack dummy. Some systems (e.g. Sony news) give
another signal besides SIGTRAP, so check here as well as
above.''
If someone ever tries to get call dummys on a
non-executable stack to work (where the target would stop
with something like a SIGSEGV), then those tests might need
to be re-instated. Given, however, that the tests were only
enabled when momentary breakpoints were not being used, I
suspect that it won't be the case.
NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
be necessary for call dummies on a non-executable stack on
SPARC. */
if (ecs->event_thread->stop_signal == TARGET_SIGNAL_TRAP)
ecs->random_signal
= !(bpstat_explains_signal (ecs->event_thread->stop_bpstat)
|| ecs->event_thread->trap_expected
|| (ecs->event_thread->step_range_end
&& ecs->event_thread->step_resume_breakpoint == NULL));
else
{
ecs->random_signal = !bpstat_explains_signal (ecs->event_thread->stop_bpstat);
if (!ecs->random_signal)
ecs->event_thread->stop_signal = TARGET_SIGNAL_TRAP;
}
}
/* When we reach this point, we've pretty much decided
that the reason for stopping must've been a random
(unexpected) signal. */
else
ecs->random_signal = 1;
process_event_stop_test:
/* For the program's own signals, act according to
the signal handling tables. */
if (ecs->random_signal)
{
/* Signal not for debugging purposes. */
int printed = 0;
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: random signal %d\n",
ecs->event_thread->stop_signal);
stopped_by_random_signal = 1;
if (signal_print[ecs->event_thread->stop_signal])
{
printed = 1;
target_terminal_ours_for_output ();
print_stop_reason (SIGNAL_RECEIVED, ecs->event_thread->stop_signal);
}
/* Always stop on signals if we're either just gaining control
of the program, or the user explicitly requested this thread
to remain stopped. */
if (stop_soon != NO_STOP_QUIETLY
|| ecs->event_thread->stop_requested
|| signal_stop_state (ecs->event_thread->stop_signal))
{
stop_stepping (ecs);
return;
}
/* If not going to stop, give terminal back
if we took it away. */
else if (printed)
target_terminal_inferior ();
/* Clear the signal if it should not be passed. */
if (signal_program[ecs->event_thread->stop_signal] == 0)
ecs->event_thread->stop_signal = TARGET_SIGNAL_0;
if (ecs->event_thread->prev_pc == read_pc ()
&& ecs->event_thread->trap_expected
&& ecs->event_thread->step_resume_breakpoint == NULL)
{
/* We were just starting a new sequence, attempting to
single-step off of a breakpoint and expecting a SIGTRAP.
Instead this signal arrives. This signal will take us out
of the stepping range so GDB needs to remember to, when
the signal handler returns, resume stepping off that
breakpoint. */
/* To simplify things, "continue" is forced to use the same
code paths as single-step - set a breakpoint at the
signal return address and then, once hit, step off that
breakpoint. */
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog,
"infrun: signal arrived while stepping over "
"breakpoint\n");
insert_step_resume_breakpoint_at_frame (get_current_frame ());
ecs->event_thread->step_after_step_resume_breakpoint = 1;
keep_going (ecs);
return;
}
if (ecs->event_thread->step_range_end != 0
&& ecs->event_thread->stop_signal != TARGET_SIGNAL_0
&& (ecs->event_thread->step_range_start <= stop_pc
&& stop_pc < ecs->event_thread->step_range_end)
&& frame_id_eq (get_frame_id (get_current_frame ()),
ecs->event_thread->step_frame_id)
&& ecs->event_thread->step_resume_breakpoint == NULL)
{
/* The inferior is about to take a signal that will take it
out of the single step range. Set a breakpoint at the
current PC (which is presumably where the signal handler
will eventually return) and then allow the inferior to
run free.
Note that this is only needed for a signal delivered
while in the single-step range. Nested signals aren't a
problem as they eventually all return. */
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog,
"infrun: signal may take us out of "
"single-step range\n");
insert_step_resume_breakpoint_at_frame (get_current_frame ());
keep_going (ecs);
return;
}
/* Note: step_resume_breakpoint may be non-NULL. This occures
when either there's a nested signal, or when there's a
pending signal enabled just as the signal handler returns
(leaving the inferior at the step-resume-breakpoint without
actually executing it). Either way continue until the
breakpoint is really hit. */
keep_going (ecs);
return;
}
/* Handle cases caused by hitting a breakpoint. */
{
CORE_ADDR jmp_buf_pc;
struct bpstat_what what;
what = bpstat_what (ecs->event_thread->stop_bpstat);
if (what.call_dummy)
{
stop_stack_dummy = 1;
}
switch (what.main_action)
{
case BPSTAT_WHAT_SET_LONGJMP_RESUME:
/* If we hit the breakpoint at longjmp while stepping, we
install a momentary breakpoint at the target of the
jmp_buf. */
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog,
"infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
ecs->event_thread->stepping_over_breakpoint = 1;
if (!gdbarch_get_longjmp_target_p (current_gdbarch)
|| !gdbarch_get_longjmp_target (current_gdbarch,
get_current_frame (), &jmp_buf_pc))
{
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "\
infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME (!gdbarch_get_longjmp_target)\n");
keep_going (ecs);
return;
}
/* We're going to replace the current step-resume breakpoint
with a longjmp-resume breakpoint. */
delete_step_resume_breakpoint (ecs->event_thread);
/* Insert a breakpoint at resume address. */
insert_longjmp_resume_breakpoint (jmp_buf_pc);
keep_going (ecs);
return;
case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME:
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog,
"infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
gdb_assert (ecs->event_thread->step_resume_breakpoint != NULL);
delete_step_resume_breakpoint (ecs->event_thread);
ecs->event_thread->stop_step = 1;
print_stop_reason (END_STEPPING_RANGE, 0);
stop_stepping (ecs);
return;
case BPSTAT_WHAT_SINGLE:
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_SINGLE\n");
ecs->event_thread->stepping_over_breakpoint = 1;
/* Still need to check other stuff, at least the case
where we are stepping and step out of the right range. */
break;
case BPSTAT_WHAT_STOP_NOISY:
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
stop_print_frame = 1;
/* We are about to nuke the step_resume_breakpointt via the
cleanup chain, so no need to worry about it here. */
stop_stepping (ecs);
return;
case BPSTAT_WHAT_STOP_SILENT:
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
stop_print_frame = 0;
/* We are about to nuke the step_resume_breakpoin via the
cleanup chain, so no need to worry about it here. */
stop_stepping (ecs);
return;
case BPSTAT_WHAT_STEP_RESUME:
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
delete_step_resume_breakpoint (ecs->event_thread);
if (ecs->event_thread->step_after_step_resume_breakpoint)
{
/* Back when the step-resume breakpoint was inserted, we
were trying to single-step off a breakpoint. Go back
to doing that. */
ecs->event_thread->step_after_step_resume_breakpoint = 0;
ecs->event_thread->stepping_over_breakpoint = 1;
keep_going (ecs);
return;
}
if (stop_pc == ecs->stop_func_start
&& execution_direction == EXEC_REVERSE)
{
/* We are stepping over a function call in reverse, and
just hit the step-resume breakpoint at the start
address of the function. Go back to single-stepping,
which should take us back to the function call. */
ecs->event_thread->stepping_over_breakpoint = 1;
keep_going (ecs);
return;
}
break;
case BPSTAT_WHAT_CHECK_SHLIBS:
{
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_CHECK_SHLIBS\n");
/* Check for any newly added shared libraries if we're
supposed to be adding them automatically. Switch
terminal for any messages produced by
breakpoint_re_set. */
target_terminal_ours_for_output ();
/* NOTE: cagney/2003-11-25: Make certain that the target
stack's section table is kept up-to-date. Architectures,
(e.g., PPC64), use the section table to perform
operations such as address => section name and hence
require the table to contain all sections (including
those found in shared libraries). */
/* NOTE: cagney/2003-11-25: Pass current_target and not
exec_ops to SOLIB_ADD. This is because current GDB is
only tooled to propagate section_table changes out from
the "current_target" (see target_resize_to_sections), and
not up from the exec stratum. This, of course, isn't
right. "infrun.c" should only interact with the
exec/process stratum, instead relying on the target stack
to propagate relevant changes (stop, section table
changed, ...) up to other layers. */
#ifdef SOLIB_ADD
SOLIB_ADD (NULL, 0, ¤t_target, auto_solib_add);
#else
solib_add (NULL, 0, ¤t_target, auto_solib_add);
#endif
target_terminal_inferior ();
/* If requested, stop when the dynamic linker notifies
gdb of events. This allows the user to get control
and place breakpoints in initializer routines for
dynamically loaded objects (among other things). */
if (stop_on_solib_events || stop_stack_dummy)
{
stop_stepping (ecs);
return;
}
else
{
/* We want to step over this breakpoint, then keep going. */
ecs->event_thread->stepping_over_breakpoint = 1;
break;
}
}
break;
case BPSTAT_WHAT_LAST:
/* Not a real code, but listed here to shut up gcc -Wall. */
case BPSTAT_WHAT_KEEP_CHECKING:
break;
}
}
/* We come here if we hit a breakpoint but should not
stop for it. Possibly we also were stepping
and should stop for that. So fall through and
test for stepping. But, if not stepping,
do not stop. */
/* In all-stop mode, if we're currently stepping but have stopped in
some other thread, we need to switch back to the stepped thread. */
if (!non_stop)
{
struct thread_info *tp;
tp = iterate_over_threads (currently_stepping_callback,
ecs->event_thread);
if (tp)
{
/* However, if the current thread is blocked on some internal
breakpoint, and we simply need to step over that breakpoint
to get it going again, do that first. */
if ((ecs->event_thread->trap_expected
&& ecs->event_thread->stop_signal != TARGET_SIGNAL_TRAP)
|| ecs->event_thread->stepping_over_breakpoint)
{
keep_going (ecs);
return;
}
/* Otherwise, we no longer expect a trap in the current thread.
Clear the trap_expected flag before switching back -- this is
what keep_going would do as well, if we called it. */
ecs->event_thread->trap_expected = 0;
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog,
"infrun: switching back to stepped thread\n");
ecs->event_thread = tp;
ecs->ptid = tp->ptid;
context_switch (ecs->ptid);
keep_going (ecs);
return;
}
}
/* Are we stepping to get the inferior out of the dynamic linker's
hook (and possibly the dld itself) after catching a shlib
event? */
if (ecs->event_thread->stepping_through_solib_after_catch)
{
#if defined(SOLIB_ADD)
/* Have we reached our destination? If not, keep going. */
if (SOLIB_IN_DYNAMIC_LINKER (PIDGET (ecs->ptid), stop_pc))
{
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: stepping in dynamic linker\n");
ecs->event_thread->stepping_over_breakpoint = 1;
keep_going (ecs);
return;
}
#endif
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: step past dynamic linker\n");
/* Else, stop and report the catchpoint(s) whose triggering
caused us to begin stepping. */
ecs->event_thread->stepping_through_solib_after_catch = 0;
bpstat_clear (&ecs->event_thread->stop_bpstat);
ecs->event_thread->stop_bpstat
= bpstat_copy (ecs->event_thread->stepping_through_solib_catchpoints);
bpstat_clear (&ecs->event_thread->stepping_through_solib_catchpoints);
stop_print_frame = 1;
stop_stepping (ecs);
return;
}
if (ecs->event_thread->step_resume_breakpoint)
{
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog,
"infrun: step-resume breakpoint is inserted\n");
/* Having a step-resume breakpoint overrides anything
else having to do with stepping commands until
that breakpoint is reached. */
keep_going (ecs);
return;
}
if (ecs->event_thread->step_range_end == 0)
{
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: no stepping, continue\n");
/* Likewise if we aren't even stepping. */
keep_going (ecs);
return;
}
/* If stepping through a line, keep going if still within it.
Note that step_range_end is the address of the first instruction
beyond the step range, and NOT the address of the last instruction
within it! */
if (stop_pc >= ecs->event_thread->step_range_start
&& stop_pc < ecs->event_thread->step_range_end)
{
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: stepping inside range [0x%s-0x%s]\n",
paddr_nz (ecs->event_thread->step_range_start),
paddr_nz (ecs->event_thread->step_range_end));
/* When stepping backward, stop at beginning of line range
(unless it's the function entry point, in which case
keep going back to the call point). */
if (stop_pc == ecs->event_thread->step_range_start
&& stop_pc != ecs->stop_func_start
&& execution_direction == EXEC_REVERSE)
{
ecs->event_thread->stop_step = 1;
print_stop_reason (END_STEPPING_RANGE, 0);
stop_stepping (ecs);
}
else
keep_going (ecs);
return;
}
/* We stepped out of the stepping range. */
/* If we are stepping at the source level and entered the runtime
loader dynamic symbol resolution code, we keep on single stepping
until we exit the run time loader code and reach the callee's
address. */
if (ecs->event_thread->step_over_calls == STEP_OVER_UNDEBUGGABLE
&& in_solib_dynsym_resolve_code (stop_pc))
{
CORE_ADDR pc_after_resolver =
gdbarch_skip_solib_resolver (current_gdbarch, stop_pc);
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: stepped into dynsym resolve code\n");
if (pc_after_resolver)
{
/* Set up a step-resume breakpoint at the address
indicated by SKIP_SOLIB_RESOLVER. */
struct symtab_and_line sr_sal;
init_sal (&sr_sal);
sr_sal.pc = pc_after_resolver;
insert_step_resume_breakpoint_at_sal (sr_sal, null_frame_id);
}
keep_going (ecs);
return;
}
if (ecs->event_thread->step_range_end != 1
&& (ecs->event_thread->step_over_calls == STEP_OVER_UNDEBUGGABLE
|| ecs->event_thread->step_over_calls == STEP_OVER_ALL)
&& get_frame_type (get_current_frame ()) == SIGTRAMP_FRAME)
{
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: stepped into signal trampoline\n");
/* The inferior, while doing a "step" or "next", has ended up in
a signal trampoline (either by a signal being delivered or by
the signal handler returning). Just single-step until the
inferior leaves the trampoline (either by calling the handler
or returning). */
keep_going (ecs);
return;
}
/* Check for subroutine calls. The check for the current frame
equalling the step ID is not necessary - the check of the
previous frame's ID is sufficient - but it is a common case and
cheaper than checking the previous frame's ID.
NOTE: frame_id_eq will never report two invalid frame IDs as
being equal, so to get into this block, both the current and
previous frame must have valid frame IDs. */
if (!frame_id_eq (get_frame_id (get_current_frame ()),
ecs->event_thread->step_frame_id)
&& (frame_id_eq (frame_unwind_id (get_current_frame ()),
ecs->event_thread->step_frame_id)
|| execution_direction == EXEC_REVERSE))
{
CORE_ADDR real_stop_pc;
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: stepped into subroutine\n");
if ((ecs->event_thread->step_over_calls == STEP_OVER_NONE)
|| ((ecs->event_thread->step_range_end == 1)
&& in_prologue (ecs->event_thread->prev_pc,
ecs->stop_func_start)))
{
/* I presume that step_over_calls is only 0 when we're
supposed to be stepping at the assembly language level
("stepi"). Just stop. */
/* Also, maybe we just did a "nexti" inside a prolog, so we
thought it was a subroutine call but it was not. Stop as
well. FENN */
ecs->event_thread->stop_step = 1;
print_stop_reason (END_STEPPING_RANGE, 0);
stop_stepping (ecs);
return;
}
if (ecs->event_thread->step_over_calls == STEP_OVER_ALL)
{
/* We're doing a "next".
Normal (forward) execution: set a breakpoint at the
callee's return address (the address at which the caller
will resume).
Reverse (backward) execution. set the step-resume
breakpoint at the start of the function that we just
stepped into (backwards), and continue to there. When we
get there, we'll need to single-step back to the caller. */
if (execution_direction == EXEC_REVERSE)
{
struct symtab_and_line sr_sal;
if (ecs->stop_func_start == 0
&& in_solib_dynsym_resolve_code (stop_pc))
{
/* Stepped into runtime loader dynamic symbol
resolution code. Since we're in reverse,
we have already backed up through the runtime
loader and the dynamic function. This is just
the trampoline (jump table).
Just keep stepping, we'll soon be home.
*/
keep_going (ecs);
return;
}
/* Normal (staticly linked) function call return. */
init_sal (&sr_sal);
sr_sal.pc = ecs->stop_func_start;
insert_step_resume_breakpoint_at_sal (sr_sal, null_frame_id);
}
else
insert_step_resume_breakpoint_at_caller (get_current_frame ());
keep_going (ecs);
return;
}
/* If we are in a function call trampoline (a stub between the
calling routine and the real function), locate the real
function. That's what tells us (a) whether we want to step
into it at all, and (b) what prologue we want to run to the
end of, if we do step into it. */
real_stop_pc = skip_language_trampoline (get_current_frame (), stop_pc);
if (real_stop_pc == 0)
real_stop_pc = gdbarch_skip_trampoline_code
(current_gdbarch, get_current_frame (), stop_pc);
if (real_stop_pc != 0)
ecs->stop_func_start = real_stop_pc;
if (real_stop_pc != 0 && in_solib_dynsym_resolve_code (real_stop_pc))
{
struct symtab_and_line sr_sal;
init_sal (&sr_sal);
sr_sal.pc = ecs->stop_func_start;
insert_step_resume_breakpoint_at_sal (sr_sal, null_frame_id);
keep_going (ecs);
return;
}
/* If we have line number information for the function we are
thinking of stepping into, step into it.
If there are several symtabs at that PC (e.g. with include
files), just want to know whether *any* of them have line
numbers. find_pc_line handles this. */
{
struct symtab_and_line tmp_sal;
tmp_sal = find_pc_line (ecs->stop_func_start, 0);
if (tmp_sal.line != 0)
{
if (execution_direction == EXEC_REVERSE)
handle_step_into_function_backward (ecs);
else
handle_step_into_function (ecs);
return;
}
}
/* If we have no line number and the step-stop-if-no-debug is
set, we stop the step so that the user has a chance to switch
in assembly mode. */
if (ecs->event_thread->step_over_calls == STEP_OVER_UNDEBUGGABLE
&& step_stop_if_no_debug)
{
ecs->event_thread->stop_step = 1;
print_stop_reason (END_STEPPING_RANGE, 0);
stop_stepping (ecs);
return;
}
if (execution_direction == EXEC_REVERSE)
{
/* Set a breakpoint at callee's start address.
From there we can step once and be back in the caller. */
struct symtab_and_line sr_sal;
init_sal (&sr_sal);
sr_sal.pc = ecs->stop_func_start;
insert_step_resume_breakpoint_at_sal (sr_sal, null_frame_id);
}
else
/* Set a breakpoint at callee's return address (the address
at which the caller will resume). */
insert_step_resume_breakpoint_at_caller (get_current_frame ());
keep_going (ecs);
return;
}
/* If we're in the return path from a shared library trampoline,
we want to proceed through the trampoline when stepping. */
if (gdbarch_in_solib_return_trampoline (current_gdbarch,
stop_pc, ecs->stop_func_name))
{
/* Determine where this trampoline returns. */
CORE_ADDR real_stop_pc;
real_stop_pc = gdbarch_skip_trampoline_code
(current_gdbarch, get_current_frame (), stop_pc);
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: stepped into solib return tramp\n");
/* Only proceed through if we know where it's going. */
if (real_stop_pc)
{
/* And put the step-breakpoint there and go until there. */
struct symtab_and_line sr_sal;
init_sal (&sr_sal); /* initialize to zeroes */
sr_sal.pc = real_stop_pc;
sr_sal.section = find_pc_overlay (sr_sal.pc);
/* Do not specify what the fp should be when we stop since
on some machines the prologue is where the new fp value
is established. */
insert_step_resume_breakpoint_at_sal (sr_sal, null_frame_id);
/* Restart without fiddling with the step ranges or
other state. */
keep_going (ecs);
return;
}
}
stop_pc_sal = find_pc_line (stop_pc, 0);
/* NOTE: tausq/2004-05-24: This if block used to be done before all
the trampoline processing logic, however, there are some trampolines
that have no names, so we should do trampoline handling first. */
if (ecs->event_thread->step_over_calls == STEP_OVER_UNDEBUGGABLE
&& ecs->stop_func_name == NULL
&& stop_pc_sal.line == 0)
{
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: stepped into undebuggable function\n");
/* The inferior just stepped into, or returned to, an
undebuggable function (where there is no debugging information
and no line number corresponding to the address where the
inferior stopped). Since we want to skip this kind of code,
we keep going until the inferior returns from this
function - unless the user has asked us not to (via
set step-mode) or we no longer know how to get back
to the call site. */
if (step_stop_if_no_debug
|| !frame_id_p (frame_unwind_id (get_current_frame ())))
{
/* If we have no line number and the step-stop-if-no-debug
is set, we stop the step so that the user has a chance to
switch in assembly mode. */
ecs->event_thread->stop_step = 1;
print_stop_reason (END_STEPPING_RANGE, 0);
stop_stepping (ecs);
return;
}
else
{
/* Set a breakpoint at callee's return address (the address
at which the caller will resume). */
insert_step_resume_breakpoint_at_caller (get_current_frame ());
keep_going (ecs);
return;
}
}
if (ecs->event_thread->step_range_end == 1)
{
/* It is stepi or nexti. We always want to stop stepping after
one instruction. */
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: stepi/nexti\n");
ecs->event_thread->stop_step = 1;
print_stop_reason (END_STEPPING_RANGE, 0);
stop_stepping (ecs);
return;
}
if (stop_pc_sal.line == 0)
{
/* We have no line number information. That means to stop
stepping (does this always happen right after one instruction,
when we do "s" in a function with no line numbers,
or can this happen as a result of a return or longjmp?). */
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: no line number info\n");
ecs->event_thread->stop_step = 1;
print_stop_reason (END_STEPPING_RANGE, 0);
stop_stepping (ecs);
return;
}
if ((stop_pc == stop_pc_sal.pc)
&& (ecs->event_thread->current_line != stop_pc_sal.line
|| ecs->event_thread->current_symtab != stop_pc_sal.symtab))
{
/* We are at the start of a different line. So stop. Note that
we don't stop if we step into the middle of a different line.
That is said to make things like for (;;) statements work
better. */
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: stepped to a different line\n");
ecs->event_thread->stop_step = 1;
print_stop_reason (END_STEPPING_RANGE, 0);
stop_stepping (ecs);
return;
}
/* We aren't done stepping.
Optimize by setting the stepping range to the line.
(We might not be in the original line, but if we entered a
new line in mid-statement, we continue stepping. This makes
things like for(;;) statements work better.) */
ecs->event_thread->step_range_start = stop_pc_sal.pc;
ecs->event_thread->step_range_end = stop_pc_sal.end;
ecs->event_thread->step_frame_id = get_frame_id (get_current_frame ());
ecs->event_thread->current_line = stop_pc_sal.line;
ecs->event_thread->current_symtab = stop_pc_sal.symtab;
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: keep going\n");
keep_going (ecs);
}
/* Are we in the middle of stepping? */
static int
currently_stepping_thread (struct thread_info *tp)
{
return (tp->step_range_end && tp->step_resume_breakpoint == NULL)
|| tp->trap_expected
|| tp->stepping_through_solib_after_catch;
}
static int
currently_stepping_callback (struct thread_info *tp, void *data)
{
/* Return true if any thread *but* the one passed in "data" is
in the middle of stepping. */
return tp != data && currently_stepping_thread (tp);
}
static int
currently_stepping (struct thread_info *tp)
{
return currently_stepping_thread (tp) || bpstat_should_step ();
}
/* Inferior has stepped into a subroutine call with source code that
we should not step over. Do step to the first line of code in
it. */
static void
handle_step_into_function (struct execution_control_state *ecs)
{
struct symtab *s;
struct symtab_and_line stop_func_sal, sr_sal;
s = find_pc_symtab (stop_pc);
if (s && s->language != language_asm)
ecs->stop_func_start = gdbarch_skip_prologue (current_gdbarch,
ecs->stop_func_start);
stop_func_sal = find_pc_line (ecs->stop_func_start, 0);
/* Use the step_resume_break to step until the end of the prologue,
even if that involves jumps (as it seems to on the vax under
4.2). */
/* If the prologue ends in the middle of a source line, continue to
the end of that source line (if it is still within the function).
Otherwise, just go to end of prologue. */
if (stop_func_sal.end
&& stop_func_sal.pc != ecs->stop_func_start
&& stop_func_sal.end < ecs->stop_func_end)
ecs->stop_func_start = stop_func_sal.end;
/* Architectures which require breakpoint adjustment might not be able
to place a breakpoint at the computed address. If so, the test
``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
ecs->stop_func_start to an address at which a breakpoint may be
legitimately placed.
Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
made, GDB will enter an infinite loop when stepping through
optimized code consisting of VLIW instructions which contain
subinstructions corresponding to different source lines. On
FR-V, it's not permitted to place a breakpoint on any but the
first subinstruction of a VLIW instruction. When a breakpoint is
set, GDB will adjust the breakpoint address to the beginning of
the VLIW instruction. Thus, we need to make the corresponding
adjustment here when computing the stop address. */
if (gdbarch_adjust_breakpoint_address_p (current_gdbarch))
{
ecs->stop_func_start
= gdbarch_adjust_breakpoint_address (current_gdbarch,
ecs->stop_func_start);
}
if (ecs->stop_func_start == stop_pc)
{
/* We are already there: stop now. */
ecs->event_thread->stop_step = 1;
print_stop_reason (END_STEPPING_RANGE, 0);
stop_stepping (ecs);
return;
}
else
{
/* Put the step-breakpoint there and go until there. */
init_sal (&sr_sal); /* initialize to zeroes */
sr_sal.pc = ecs->stop_func_start;
sr_sal.section = find_pc_overlay (ecs->stop_func_start);
/* Do not specify what the fp should be when we stop since on
some machines the prologue is where the new fp value is
established. */
insert_step_resume_breakpoint_at_sal (sr_sal, null_frame_id);
/* And make sure stepping stops right away then. */
ecs->event_thread->step_range_end = ecs->event_thread->step_range_start;
}
keep_going (ecs);
}
/* Inferior has stepped backward into a subroutine call with source
code that we should not step over. Do step to the beginning of the
last line of code in it. */
static void
handle_step_into_function_backward (struct execution_control_state *ecs)
{
struct symtab *s;
struct symtab_and_line stop_func_sal, sr_sal;
s = find_pc_symtab (stop_pc);
if (s && s->language != language_asm)
ecs->stop_func_start = gdbarch_skip_prologue (current_gdbarch,
ecs->stop_func_start);
stop_func_sal = find_pc_line (stop_pc, 0);
/* OK, we're just going to keep stepping here. */
if (stop_func_sal.pc == stop_pc)
{
/* We're there already. Just stop stepping now. */
ecs->event_thread->stop_step = 1;
print_stop_reason (END_STEPPING_RANGE, 0);
stop_stepping (ecs);
}
else
{
/* Else just reset the step range and keep going.
No step-resume breakpoint, they don't work for
epilogues, which can have multiple entry paths. */
ecs->event_thread->step_range_start = stop_func_sal.pc;
ecs->event_thread->step_range_end = stop_func_sal.end;
keep_going (ecs);
}
return;
}
/* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
This is used to both functions and to skip over code. */
static void
insert_step_resume_breakpoint_at_sal (struct symtab_and_line sr_sal,
struct frame_id sr_id)
{
/* There should never be more than one step-resume or longjmp-resume
breakpoint per thread, so we should never be setting a new
step_resume_breakpoint when one is already active. */
gdb_assert (inferior_thread ()->step_resume_breakpoint == NULL);
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog,
"infrun: inserting step-resume breakpoint at 0x%s\n",
paddr_nz (sr_sal.pc));
inferior_thread ()->step_resume_breakpoint
= set_momentary_breakpoint (sr_sal, sr_id, bp_step_resume);
}
/* Insert a "step-resume breakpoint" at RETURN_FRAME.pc. This is used
to skip a potential signal handler.
This is called with the interrupted function's frame. The signal
handler, when it returns, will resume the interrupted function at
RETURN_FRAME.pc. */
static void
insert_step_resume_breakpoint_at_frame (struct frame_info *return_frame)
{
struct symtab_and_line sr_sal;
gdb_assert (return_frame != NULL);
init_sal (&sr_sal); /* initialize to zeros */
sr_sal.pc = gdbarch_addr_bits_remove
(current_gdbarch, get_frame_pc (return_frame));
sr_sal.section = find_pc_overlay (sr_sal.pc);
insert_step_resume_breakpoint_at_sal (sr_sal, get_frame_id (return_frame));
}
/* Similar to insert_step_resume_breakpoint_at_frame, except
but a breakpoint at the previous frame's PC. This is used to
skip a function after stepping into it (for "next" or if the called
function has no debugging information).
The current function has almost always been reached by single
stepping a call or return instruction. NEXT_FRAME belongs to the
current function, and the breakpoint will be set at the caller's
resume address.
This is a separate function rather than reusing
insert_step_resume_breakpoint_at_frame in order to avoid
get_prev_frame, which may stop prematurely (see the implementation
of frame_unwind_id for an example). */
static void
insert_step_resume_breakpoint_at_caller (struct frame_info *next_frame)
{
struct symtab_and_line sr_sal;
/* We shouldn't have gotten here if we don't know where the call site
is. */
gdb_assert (frame_id_p (frame_unwind_id (next_frame)));
init_sal (&sr_sal); /* initialize to zeros */
sr_sal.pc = gdbarch_addr_bits_remove
(current_gdbarch, frame_pc_unwind (next_frame));
sr_sal.section = find_pc_overlay (sr_sal.pc);
insert_step_resume_breakpoint_at_sal (sr_sal, frame_unwind_id (next_frame));
}
/* Insert a "longjmp-resume" breakpoint at PC. This is used to set a
new breakpoint at the target of a jmp_buf. The handling of
longjmp-resume uses the same mechanisms used for handling
"step-resume" breakpoints. */
static void
insert_longjmp_resume_breakpoint (CORE_ADDR pc)
{
/* There should never be more than one step-resume or longjmp-resume
breakpoint per thread, so we should never be setting a new
longjmp_resume_breakpoint when one is already active. */
gdb_assert (inferior_thread ()->step_resume_breakpoint == NULL);
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog,
"infrun: inserting longjmp-resume breakpoint at 0x%s\n",
paddr_nz (pc));
inferior_thread ()->step_resume_breakpoint =
set_momentary_breakpoint_at_pc (pc, bp_longjmp_resume);
}
static void
stop_stepping (struct execution_control_state *ecs)
{
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: stop_stepping\n");
/* Let callers know we don't want to wait for the inferior anymore. */
ecs->wait_some_more = 0;
}
/* This function handles various cases where we need to continue
waiting for the inferior. */
/* (Used to be the keep_going: label in the old wait_for_inferior) */
static void
keep_going (struct execution_control_state *ecs)
{
/* Save the pc before execution, to compare with pc after stop. */
ecs->event_thread->prev_pc = read_pc (); /* Might have been DECR_AFTER_BREAK */
/* If we did not do break;, it means we should keep running the
inferior and not return to debugger. */
if (ecs->event_thread->trap_expected
&& ecs->event_thread->stop_signal != TARGET_SIGNAL_TRAP)
{
/* We took a signal (which we are supposed to pass through to
the inferior, else we'd not get here) and we haven't yet
gotten our trap. Simply continue. */
resume (currently_stepping (ecs->event_thread),
ecs->event_thread->stop_signal);
}
else
{
/* Either the trap was not expected, but we are continuing
anyway (the user asked that this signal be passed to the
child)
-- or --
The signal was SIGTRAP, e.g. it was our signal, but we
decided we should resume from it.
We're going to run this baby now!
Note that insert_breakpoints won't try to re-insert
already inserted breakpoints. Therefore, we don't
care if breakpoints were already inserted, or not. */
if (ecs->event_thread->stepping_over_breakpoint)
{
if (! use_displaced_stepping (current_gdbarch))
/* Since we can't do a displaced step, we have to remove
the breakpoint while we step it. To keep things
simple, we remove them all. */
remove_breakpoints ();
}
else
{
struct gdb_exception e;
/* Stop stepping when inserting breakpoints
has failed. */
TRY_CATCH (e, RETURN_MASK_ERROR)
{
insert_breakpoints ();
}
if (e.reason < 0)
{
stop_stepping (ecs);
return;
}
}
ecs->event_thread->trap_expected = ecs->event_thread->stepping_over_breakpoint;
/* Do not deliver SIGNAL_TRAP (except when the user explicitly
specifies that such a signal should be delivered to the
target program).
Typically, this would occure when a user is debugging a
target monitor on a simulator: the target monitor sets a
breakpoint; the simulator encounters this break-point and
halts the simulation handing control to GDB; GDB, noteing
that the break-point isn't valid, returns control back to the
simulator; the simulator then delivers the hardware
equivalent of a SIGNAL_TRAP to the program being debugged. */
if (ecs->event_thread->stop_signal == TARGET_SIGNAL_TRAP
&& !signal_program[ecs->event_thread->stop_signal])
ecs->event_thread->stop_signal = TARGET_SIGNAL_0;
resume (currently_stepping (ecs->event_thread),
ecs->event_thread->stop_signal);
}
prepare_to_wait (ecs);
}
/* This function normally comes after a resume, before
handle_inferior_event exits. It takes care of any last bits of
housekeeping, and sets the all-important wait_some_more flag. */
static void
prepare_to_wait (struct execution_control_state *ecs)
{
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog, "infrun: prepare_to_wait\n");
if (infwait_state == infwait_normal_state)
{
overlay_cache_invalid = 1;
/* We have to invalidate the registers BEFORE calling
target_wait because they can be loaded from the target while
in target_wait. This makes remote debugging a bit more
efficient for those targets that provide critical registers
as part of their normal status mechanism. */
registers_changed ();
waiton_ptid = pid_to_ptid (-1);
}
/* This is the old end of the while loop. Let everybody know we
want to wait for the inferior some more and get called again
soon. */
ecs->wait_some_more = 1;
}
/* Print why the inferior has stopped. We always print something when
the inferior exits, or receives a signal. The rest of the cases are
dealt with later on in normal_stop() and print_it_typical(). Ideally
there should be a call to this function from handle_inferior_event()
each time stop_stepping() is called.*/
static void
print_stop_reason (enum inferior_stop_reason stop_reason, int stop_info)
{
switch (stop_reason)
{
case END_STEPPING_RANGE:
/* We are done with a step/next/si/ni command. */
/* For now print nothing. */
/* Print a message only if not in the middle of doing a "step n"
operation for n > 1 */
if (!inferior_thread ()->step_multi
|| !inferior_thread ()->stop_step)
if (ui_out_is_mi_like_p (uiout))
ui_out_field_string
(uiout, "reason",
async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE));
break;
case SIGNAL_EXITED:
/* The inferior was terminated by a signal. */
annotate_signalled ();
if (ui_out_is_mi_like_p (uiout))
ui_out_field_string
(uiout, "reason",
async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED));
ui_out_text (uiout, "\nProgram terminated with signal ");
annotate_signal_name ();
ui_out_field_string (uiout, "signal-name",
target_signal_to_name (stop_info));
annotate_signal_name_end ();
ui_out_text (uiout, ", ");
annotate_signal_string ();
ui_out_field_string (uiout, "signal-meaning",
target_signal_to_string (stop_info));
annotate_signal_string_end ();
ui_out_text (uiout, ".\n");
ui_out_text (uiout, "The program no longer exists.\n");
break;
case EXITED:
/* The inferior program is finished. */
annotate_exited (stop_info);
if (stop_info)
{
if (ui_out_is_mi_like_p (uiout))
ui_out_field_string (uiout, "reason",
async_reason_lookup (EXEC_ASYNC_EXITED));
ui_out_text (uiout, "\nProgram exited with code ");
ui_out_field_fmt (uiout, "exit-code", "0%o",
(unsigned int) stop_info);
ui_out_text (uiout, ".\n");
}
else
{
if (ui_out_is_mi_like_p (uiout))
ui_out_field_string
(uiout, "reason",
async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY));
ui_out_text (uiout, "\nProgram exited normally.\n");
}
/* Support the --return-child-result option. */
return_child_result_value = stop_info;
break;
case SIGNAL_RECEIVED:
/* Signal received. The signal table tells us to print about
it. */
annotate_signal ();
if (stop_info == TARGET_SIGNAL_0 && !ui_out_is_mi_like_p (uiout))
{
struct thread_info *t = inferior_thread ();
ui_out_text (uiout, "\n[");
ui_out_field_string (uiout, "thread-name",
target_pid_to_str (t->ptid));
ui_out_field_fmt (uiout, "thread-id", "] #%d", t->num);
ui_out_text (uiout, " stopped");
}
else
{
ui_out_text (uiout, "\nProgram received signal ");
annotate_signal_name ();
if (ui_out_is_mi_like_p (uiout))
ui_out_field_string
(uiout, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED));
ui_out_field_string (uiout, "signal-name",
target_signal_to_name (stop_info));
annotate_signal_name_end ();
ui_out_text (uiout, ", ");
annotate_signal_string ();
ui_out_field_string (uiout, "signal-meaning",
target_signal_to_string (stop_info));
annotate_signal_string_end ();
}
ui_out_text (uiout, ".\n");
break;
case NO_HISTORY:
/* Reverse execution: target ran out of history info. */
ui_out_text (uiout, "\nNo more reverse-execution history.\n");
break;
default:
internal_error (__FILE__, __LINE__,
_("print_stop_reason: unrecognized enum value"));
break;
}
}
/* Here to return control to GDB when the inferior stops for real.
Print appropriate messages, remove breakpoints, give terminal our modes.
STOP_PRINT_FRAME nonzero means print the executing frame
(pc, function, args, file, line number and line text).
BREAKPOINTS_FAILED nonzero means stop was due to error
attempting to insert breakpoints. */
void
normal_stop (void)
{
struct target_waitstatus last;
ptid_t last_ptid;
get_last_target_status (&last_ptid, &last);
/* In non-stop mode, we don't want GDB to switch threads behind the
user's back, to avoid races where the user is typing a command to
apply to thread x, but GDB switches to thread y before the user
finishes entering the command. */
/* As with the notification of thread events, we want to delay
notifying the user that we've switched thread context until
the inferior actually stops.
There's no point in saying anything if the inferior has exited.
Note that SIGNALLED here means "exited with a signal", not
"received a signal". */
if (!non_stop
&& !ptid_equal (previous_inferior_ptid, inferior_ptid)
&& target_has_execution
&& last.kind != TARGET_WAITKIND_SIGNALLED
&& last.kind != TARGET_WAITKIND_EXITED)
{
target_terminal_ours_for_output ();
printf_filtered (_("[Switching to %s]\n"),
target_pid_to_str (inferior_ptid));
annotate_thread_changed ();
previous_inferior_ptid = inferior_ptid;
}
/* NOTE drow/2004-01-17: Is this still necessary? */
/* Make sure that the current_frame's pc is correct. This
is a correction for setting up the frame info before doing
gdbarch_decr_pc_after_break */
if (target_has_execution)
/* FIXME: cagney/2002-12-06: Has the PC changed? Thanks to
gdbarch_decr_pc_after_break, the program counter can change. Ask the
frame code to check for this and sort out any resultant mess.
gdbarch_decr_pc_after_break needs to just go away. */
deprecated_update_frame_pc_hack (get_current_frame (), read_pc ());
if (!breakpoints_always_inserted_mode () && target_has_execution)
{
if (remove_breakpoints ())
{
target_terminal_ours_for_output ();
printf_filtered (_("\
Cannot remove breakpoints because program is no longer writable.\n\
It might be running in another process.\n\
Further execution is probably impossible.\n"));
}
}
/* If an auto-display called a function and that got a signal,
delete that auto-display to avoid an infinite recursion. */
if (stopped_by_random_signal)
disable_current_display ();
/* Don't print a message if in the middle of doing a "step n"
operation for n > 1 */
if (target_has_execution
&& last.kind != TARGET_WAITKIND_SIGNALLED
&& last.kind != TARGET_WAITKIND_EXITED
&& inferior_thread ()->step_multi
&& inferior_thread ()->stop_step)
goto done;
target_terminal_ours ();
/* Set the current source location. This will also happen if we
display the frame below, but the current SAL will be incorrect
during a user hook-stop function. */
if (target_has_stack && !stop_stack_dummy)
set_current_sal_from_frame (get_current_frame (), 1);
if (!target_has_stack)
goto done;
if (last.kind == TARGET_WAITKIND_SIGNALLED
|| last.kind == TARGET_WAITKIND_EXITED)
goto done;
/* Select innermost stack frame - i.e., current frame is frame 0,
and current location is based on that.
Don't do this on return from a stack dummy routine,
or if the program has exited. */
if (!stop_stack_dummy)
{
select_frame (get_current_frame ());
/* Print current location without a level number, if
we have changed functions or hit a breakpoint.
Print source line if we have one.
bpstat_print() contains the logic deciding in detail
what to print, based on the event(s) that just occurred. */
/* If --batch-silent is enabled then there's no need to print the current
source location, and to try risks causing an error message about
missing source files. */
if (stop_print_frame && !batch_silent)
{
int bpstat_ret;
int source_flag;
int do_frame_printing = 1;
struct thread_info *tp = inferior_thread ();
bpstat_ret = bpstat_print (tp->stop_bpstat);
switch (bpstat_ret)
{
case PRINT_UNKNOWN:
/* If we had hit a shared library event breakpoint,
bpstat_print would print out this message. If we hit
an OS-level shared library event, do the same
thing. */
if (last.kind == TARGET_WAITKIND_LOADED)
{
printf_filtered (_("Stopped due to shared library event\n"));
source_flag = SRC_LINE; /* something bogus */
do_frame_printing = 0;
break;
}
/* FIXME: cagney/2002-12-01: Given that a frame ID does
(or should) carry around the function and does (or
should) use that when doing a frame comparison. */
if (tp->stop_step
&& frame_id_eq (tp->step_frame_id,
get_frame_id (get_current_frame ()))
&& step_start_function == find_pc_function (stop_pc))
source_flag = SRC_LINE; /* finished step, just print source line */
else
source_flag = SRC_AND_LOC; /* print location and source line */
break;
case PRINT_SRC_AND_LOC:
source_flag = SRC_AND_LOC; /* print location and source line */
break;
case PRINT_SRC_ONLY:
source_flag = SRC_LINE;
break;
case PRINT_NOTHING:
source_flag = SRC_LINE; /* something bogus */
do_frame_printing = 0;
break;
default:
internal_error (__FILE__, __LINE__, _("Unknown value."));
}
if (ui_out_is_mi_like_p (uiout))
{
ui_out_field_int (uiout, "thread-id",
pid_to_thread_id (inferior_ptid));
if (non_stop)
{
struct cleanup *back_to = make_cleanup_ui_out_list_begin_end
(uiout, "stopped-threads");
ui_out_field_int (uiout, NULL,
pid_to_thread_id (inferior_ptid));
do_cleanups (back_to);
}
else
ui_out_field_string (uiout, "stopped-threads", "all");
}
/* The behavior of this routine with respect to the source
flag is:
SRC_LINE: Print only source line
LOCATION: Print only location
SRC_AND_LOC: Print location and source line */
if (do_frame_printing)
print_stack_frame (get_selected_frame (NULL), 0, source_flag);
/* Display the auto-display expressions. */
do_displays ();
}
}
/* Save the function value return registers, if we care.
We might be about to restore their previous contents. */
if (inferior_thread ()->proceed_to_finish)
{
/* This should not be necessary. */
if (stop_registers)
regcache_xfree (stop_registers);
/* NB: The copy goes through to the target picking up the value of
all the registers. */
stop_registers = regcache_dup (get_current_regcache ());
}
if (stop_stack_dummy)
{
/* Pop the empty frame that contains the stack dummy. POP_FRAME
ends with a setting of the current frame, so we can use that
next. */
frame_pop (get_current_frame ());
/* Set stop_pc to what it was before we called the function.
Can't rely on restore_inferior_status because that only gets
called if we don't stop in the called function. */
stop_pc = read_pc ();
select_frame (get_current_frame ());
}
done:
annotate_stopped ();
if (!suppress_stop_observer
&& !(target_has_execution
&& last.kind != TARGET_WAITKIND_SIGNALLED
&& last.kind != TARGET_WAITKIND_EXITED
&& inferior_thread ()->step_multi))
{
if (!ptid_equal (inferior_ptid, null_ptid))
observer_notify_normal_stop (inferior_thread ()->stop_bpstat);
else
observer_notify_normal_stop (NULL);
}
if (target_has_execution)
{
if (last.kind != TARGET_WAITKIND_SIGNALLED
&& last.kind != TARGET_WAITKIND_EXITED)
/* Delete the breakpoint we stopped at, if it wants to be deleted.
Delete any breakpoint that is to be deleted at the next stop. */
breakpoint_auto_delete (inferior_thread ()->stop_bpstat);
/* Mark the stopped threads accordingly. In all-stop, all
threads of all processes are stopped when we get any event
reported. In non-stop mode, only the event thread stops. If
we're handling a process exit in non-stop mode, there's
nothing to do, as threads of the dead process are gone, and
threads of any other process were left running. */
if (!non_stop)
set_running (minus_one_ptid, 0);
else if (last.kind != TARGET_WAITKIND_SIGNALLED
&& last.kind != TARGET_WAITKIND_EXITED)
set_running (inferior_ptid, 0);
}
/* Look up the hook_stop and run it (CLI internally handles problem
of stop_command's pre-hook not existing). */
if (stop_command)
catch_errors (hook_stop_stub, stop_command,
"Error while running hook_stop:\n", RETURN_MASK_ALL);
}
static int
hook_stop_stub (void *cmd)
{
execute_cmd_pre_hook ((struct cmd_list_element *) cmd);
return (0);
}
int
signal_stop_state (int signo)
{
return signal_stop[signo];
}
int
signal_print_state (int signo)
{
return signal_print[signo];
}
int
signal_pass_state (int signo)
{
return signal_program[signo];
}
int
signal_stop_update (int signo, int state)
{
int ret = signal_stop[signo];
signal_stop[signo] = state;
return ret;
}
int
signal_print_update (int signo, int state)
{
int ret = signal_print[signo];
signal_print[signo] = state;
return ret;
}
int
signal_pass_update (int signo, int state)
{
int ret = signal_program[signo];
signal_program[signo] = state;
return ret;
}
static void
sig_print_header (void)
{
printf_filtered (_("\
Signal Stop\tPrint\tPass to program\tDescription\n"));
}
static void
sig_print_info (enum target_signal oursig)
{
char *name = target_signal_to_name (oursig);
int name_padding = 13 - strlen (name);
if (name_padding <= 0)
name_padding = 0;
printf_filtered ("%s", name);
printf_filtered ("%*.*s ", name_padding, name_padding, " ");
printf_filtered ("%s\t", signal_stop[oursig] ? "Yes" : "No");
printf_filtered ("%s\t", signal_print[oursig] ? "Yes" : "No");
printf_filtered ("%s\t\t", signal_program[oursig] ? "Yes" : "No");
printf_filtered ("%s\n", target_signal_to_string (oursig));
}
/* Specify how various signals in the inferior should be handled. */
static void
handle_command (char *args, int from_tty)
{
char **argv;
int digits, wordlen;
int sigfirst, signum, siglast;
enum target_signal oursig;
int allsigs;
int nsigs;
unsigned char *sigs;
struct cleanup *old_chain;
if (args == NULL)
{
error_no_arg (_("signal to handle"));
}
/* Allocate and zero an array of flags for which signals to handle. */
nsigs = (int) TARGET_SIGNAL_LAST;
sigs = (unsigned char *) alloca (nsigs);
memset (sigs, 0, nsigs);
/* Break the command line up into args. */
argv = gdb_buildargv (args);
old_chain = make_cleanup_freeargv (argv);
/* Walk through the args, looking for signal oursigs, signal names, and
actions. Signal numbers and signal names may be interspersed with
actions, with the actions being performed for all signals cumulatively
specified. Signal ranges can be specified as <LOW>-<HIGH>. */
while (*argv != NULL)
{
wordlen = strlen (*argv);
for (digits = 0; isdigit ((*argv)[digits]); digits++)
{;
}
allsigs = 0;
sigfirst = siglast = -1;
if (wordlen >= 1 && !strncmp (*argv, "all", wordlen))
{
/* Apply action to all signals except those used by the
debugger. Silently skip those. */
allsigs = 1;
sigfirst = 0;
siglast = nsigs - 1;
}
else if (wordlen >= 1 && !strncmp (*argv, "stop", wordlen))
{
SET_SIGS (nsigs, sigs, signal_stop);
SET_SIGS (nsigs, sigs, signal_print);
}
else if (wordlen >= 1 && !strncmp (*argv, "ignore", wordlen))
{
UNSET_SIGS (nsigs, sigs, signal_program);
}
else if (wordlen >= 2 && !strncmp (*argv, "print", wordlen))
{
SET_SIGS (nsigs, sigs, signal_print);
}
else if (wordlen >= 2 && !strncmp (*argv, "pass", wordlen))
{
SET_SIGS (nsigs, sigs, signal_program);
}
else if (wordlen >= 3 && !strncmp (*argv, "nostop", wordlen))
{
UNSET_SIGS (nsigs, sigs, signal_stop);
}
else if (wordlen >= 3 && !strncmp (*argv, "noignore", wordlen))
{
SET_SIGS (nsigs, sigs, signal_program);
}
else if (wordlen >= 4 && !strncmp (*argv, "noprint", wordlen))
{
UNSET_SIGS (nsigs, sigs, signal_print);
UNSET_SIGS (nsigs, sigs, signal_stop);
}
else if (wordlen >= 4 && !strncmp (*argv, "nopass", wordlen))
{
UNSET_SIGS (nsigs, sigs, signal_program);
}
else if (digits > 0)
{
/* It is numeric. The numeric signal refers to our own
internal signal numbering from target.h, not to host/target
signal number. This is a feature; users really should be
using symbolic names anyway, and the common ones like
SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
sigfirst = siglast = (int)
target_signal_from_command (atoi (*argv));
if ((*argv)[digits] == '-')
{
siglast = (int)
target_signal_from_command (atoi ((*argv) + digits + 1));
}
if (sigfirst > siglast)
{
/* Bet he didn't figure we'd think of this case... */
signum = sigfirst;
sigfirst = siglast;
siglast = signum;
}
}
else
{
oursig = target_signal_from_name (*argv);
if (oursig != TARGET_SIGNAL_UNKNOWN)
{
sigfirst = siglast = (int) oursig;
}
else
{
/* Not a number and not a recognized flag word => complain. */
error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv);
}
}
/* If any signal numbers or symbol names were found, set flags for
which signals to apply actions to. */
for (signum = sigfirst; signum >= 0 && signum <= siglast; signum++)
{
switch ((enum target_signal) signum)
{
case TARGET_SIGNAL_TRAP:
case TARGET_SIGNAL_INT:
if (!allsigs && !sigs[signum])
{
if (query ("%s is used by the debugger.\n\
Are you sure you want to change it? ", target_signal_to_name ((enum target_signal) signum)))
{
sigs[signum] = 1;
}
else
{
printf_unfiltered (_("Not confirmed, unchanged.\n"));
gdb_flush (gdb_stdout);
}
}
break;
case TARGET_SIGNAL_0:
case TARGET_SIGNAL_DEFAULT:
case TARGET_SIGNAL_UNKNOWN:
/* Make sure that "all" doesn't print these. */
break;
default:
sigs[signum] = 1;
break;
}
}
argv++;
}
for (signum = 0; signum < nsigs; signum++)
if (sigs[signum])
{
target_notice_signals (inferior_ptid);
if (from_tty)
{
/* Show the results. */
sig_print_header ();
for (; signum < nsigs; signum++)
if (sigs[signum])
sig_print_info (signum);
}
break;
}
do_cleanups (old_chain);
}
static void
xdb_handle_command (char *args, int from_tty)
{
char **argv;
struct cleanup *old_chain;
if (args == NULL)
error_no_arg (_("xdb command"));
/* Break the command line up into args. */
argv = gdb_buildargv (args);
old_chain = make_cleanup_freeargv (argv);
if (argv[1] != (char *) NULL)
{
char *argBuf;
int bufLen;
bufLen = strlen (argv[0]) + 20;
argBuf = (char *) xmalloc (bufLen);
if (argBuf)
{
int validFlag = 1;
enum target_signal oursig;
oursig = target_signal_from_name (argv[0]);
memset (argBuf, 0, bufLen);
if (strcmp (argv[1], "Q") == 0)
sprintf (argBuf, "%s %s", argv[0], "noprint");
else
{
if (strcmp (argv[1], "s") == 0)
{
if (!signal_stop[oursig])
sprintf (argBuf, "%s %s", argv[0], "stop");
else
sprintf (argBuf, "%s %s", argv[0], "nostop");
}
else if (strcmp (argv[1], "i") == 0)
{
if (!signal_program[oursig])
sprintf (argBuf, "%s %s", argv[0], "pass");
else
sprintf (argBuf, "%s %s", argv[0], "nopass");
}
else if (strcmp (argv[1], "r") == 0)
{
if (!signal_print[oursig])
sprintf (argBuf, "%s %s", argv[0], "print");
else
sprintf (argBuf, "%s %s", argv[0], "noprint");
}
else
validFlag = 0;
}
if (validFlag)
handle_command (argBuf, from_tty);
else
printf_filtered (_("Invalid signal handling flag.\n"));
if (argBuf)
xfree (argBuf);
}
}
do_cleanups (old_chain);
}
/* Print current contents of the tables set by the handle command.
It is possible we should just be printing signals actually used
by the current target (but for things to work right when switching
targets, all signals should be in the signal tables). */
static void
signals_info (char *signum_exp, int from_tty)
{
enum target_signal oursig;
sig_print_header ();
if (signum_exp)
{
/* First see if this is a symbol name. */
oursig = target_signal_from_name (signum_exp);
if (oursig == TARGET_SIGNAL_UNKNOWN)
{
/* No, try numeric. */
oursig =
target_signal_from_command (parse_and_eval_long (signum_exp));
}
sig_print_info (oursig);
return;
}
printf_filtered ("\n");
/* These ugly casts brought to you by the native VAX compiler. */
for (oursig = TARGET_SIGNAL_FIRST;
(int) oursig < (int) TARGET_SIGNAL_LAST;
oursig = (enum target_signal) ((int) oursig + 1))
{
QUIT;
if (oursig != TARGET_SIGNAL_UNKNOWN
&& oursig != TARGET_SIGNAL_DEFAULT && oursig != TARGET_SIGNAL_0)
sig_print_info (oursig);
}
printf_filtered (_("\nUse the \"handle\" command to change these tables.\n"));
}
struct inferior_status
{
enum target_signal stop_signal;
CORE_ADDR stop_pc;
bpstat stop_bpstat;
int stop_step;
int stop_stack_dummy;
int stopped_by_random_signal;
int stepping_over_breakpoint;
CORE_ADDR step_range_start;
CORE_ADDR step_range_end;
struct frame_id step_frame_id;
enum step_over_calls_kind step_over_calls;
CORE_ADDR step_resume_break_address;
int stop_after_trap;
int stop_soon;
/* These are here because if call_function_by_hand has written some
registers and then decides to call error(), we better not have changed
any registers. */
struct regcache *registers;
/* A frame unique identifier. */
struct frame_id selected_frame_id;
int breakpoint_proceeded;
int restore_stack_info;
int proceed_to_finish;
};
/* Save all of the information associated with the inferior<==>gdb
connection. INF_STATUS is a pointer to a "struct inferior_status"
(defined in inferior.h). */
struct inferior_status *
save_inferior_status (int restore_stack_info)
{
struct inferior_status *inf_status = XMALLOC (struct inferior_status);
struct thread_info *tp = inferior_thread ();
struct inferior *inf = current_inferior ();
inf_status->stop_signal = tp->stop_signal;
inf_status->stop_pc = stop_pc;
inf_status->stop_step = tp->stop_step;
inf_status->stop_stack_dummy = stop_stack_dummy;
inf_status->stopped_by_random_signal = stopped_by_random_signal;
inf_status->stepping_over_breakpoint = tp->trap_expected;
inf_status->step_range_start = tp->step_range_start;
inf_status->step_range_end = tp->step_range_end;
inf_status->step_frame_id = tp->step_frame_id;
inf_status->step_over_calls = tp->step_over_calls;
inf_status->stop_after_trap = stop_after_trap;
inf_status->stop_soon = inf->stop_soon;
/* Save original bpstat chain here; replace it with copy of chain.
If caller's caller is walking the chain, they'll be happier if we
hand them back the original chain when restore_inferior_status is
called. */
inf_status->stop_bpstat = tp->stop_bpstat;
tp->stop_bpstat = bpstat_copy (tp->stop_bpstat);
inf_status->breakpoint_proceeded = breakpoint_proceeded;
inf_status->restore_stack_info = restore_stack_info;
inf_status->proceed_to_finish = tp->proceed_to_finish;
inf_status->registers = regcache_dup (get_current_regcache ());
inf_status->selected_frame_id = get_frame_id (get_selected_frame (NULL));
return inf_status;
}
static int
restore_selected_frame (void *args)
{
struct frame_id *fid = (struct frame_id *) args;
struct frame_info *frame;
frame = frame_find_by_id (*fid);
/* If inf_status->selected_frame_id is NULL, there was no previously
selected frame. */
if (frame == NULL)
{
warning (_("Unable to restore previously selected frame."));
return 0;
}
select_frame (frame);
return (1);
}
void
restore_inferior_status (struct inferior_status *inf_status)
{
struct thread_info *tp = inferior_thread ();
struct inferior *inf = current_inferior ();
tp->stop_signal = inf_status->stop_signal;
stop_pc = inf_status->stop_pc;
tp->stop_step = inf_status->stop_step;
stop_stack_dummy = inf_status->stop_stack_dummy;
stopped_by_random_signal = inf_status->stopped_by_random_signal;
tp->trap_expected = inf_status->stepping_over_breakpoint;
tp->step_range_start = inf_status->step_range_start;
tp->step_range_end = inf_status->step_range_end;
tp->step_frame_id = inf_status->step_frame_id;
tp->step_over_calls = inf_status->step_over_calls;
stop_after_trap = inf_status->stop_after_trap;
inf->stop_soon = inf_status->stop_soon;
bpstat_clear (&tp->stop_bpstat);
tp->stop_bpstat = inf_status->stop_bpstat;
breakpoint_proceeded = inf_status->breakpoint_proceeded;
tp->proceed_to_finish = inf_status->proceed_to_finish;
/* The inferior can be gone if the user types "print exit(0)"
(and perhaps other times). */
if (target_has_execution)
/* NB: The register write goes through to the target. */
regcache_cpy (get_current_regcache (), inf_status->registers);
regcache_xfree (inf_status->registers);
/* FIXME: If we are being called after stopping in a function which
is called from gdb, we should not be trying to restore the
selected frame; it just prints a spurious error message (The
message is useful, however, in detecting bugs in gdb (like if gdb
clobbers the stack)). In fact, should we be restoring the
inferior status at all in that case? . */
if (target_has_stack && inf_status->restore_stack_info)
{
/* The point of catch_errors is that if the stack is clobbered,
walking the stack might encounter a garbage pointer and
error() trying to dereference it. */
if (catch_errors
(restore_selected_frame, &inf_status->selected_frame_id,
"Unable to restore previously selected frame:\n",
RETURN_MASK_ERROR) == 0)
/* Error in restoring the selected frame. Select the innermost
frame. */
select_frame (get_current_frame ());
}
xfree (inf_status);
}
static void
do_restore_inferior_status_cleanup (void *sts)
{
restore_inferior_status (sts);
}
struct cleanup *
make_cleanup_restore_inferior_status (struct inferior_status *inf_status)
{
return make_cleanup (do_restore_inferior_status_cleanup, inf_status);
}
void
discard_inferior_status (struct inferior_status *inf_status)
{
/* See save_inferior_status for info on stop_bpstat. */
bpstat_clear (&inf_status->stop_bpstat);
regcache_xfree (inf_status->registers);
xfree (inf_status);
}
int
inferior_has_forked (ptid_t pid, ptid_t *child_pid)
{
struct target_waitstatus last;
ptid_t last_ptid;
get_last_target_status (&last_ptid, &last);
if (last.kind != TARGET_WAITKIND_FORKED)
return 0;
if (!ptid_equal (last_ptid, pid))
return 0;
*child_pid = last.value.related_pid;
return 1;
}
int
inferior_has_vforked (ptid_t pid, ptid_t *child_pid)
{
struct target_waitstatus last;
ptid_t last_ptid;
get_last_target_status (&last_ptid, &last);
if (last.kind != TARGET_WAITKIND_VFORKED)
return 0;
if (!ptid_equal (last_ptid, pid))
return 0;
*child_pid = last.value.related_pid;
return 1;
}
int
inferior_has_execd (ptid_t pid, char **execd_pathname)
{
struct target_waitstatus last;
ptid_t last_ptid;
get_last_target_status (&last_ptid, &last);
if (last.kind != TARGET_WAITKIND_EXECD)
return 0;
if (!ptid_equal (last_ptid, pid))
return 0;
*execd_pathname = xstrdup (last.value.execd_pathname);
return 1;
}
/* Oft used ptids */
ptid_t null_ptid;
ptid_t minus_one_ptid;
/* Create a ptid given the necessary PID, LWP, and TID components. */
ptid_t
ptid_build (int pid, long lwp, long tid)
{
ptid_t ptid;
ptid.pid = pid;
ptid.lwp = lwp;
ptid.tid = tid;
return ptid;
}
/* Create a ptid from just a pid. */
ptid_t
pid_to_ptid (int pid)
{
return ptid_build (pid, 0, 0);
}
/* Fetch the pid (process id) component from a ptid. */
int
ptid_get_pid (ptid_t ptid)
{
return ptid.pid;
}
/* Fetch the lwp (lightweight process) component from a ptid. */
long
ptid_get_lwp (ptid_t ptid)
{
return ptid.lwp;
}
/* Fetch the tid (thread id) component from a ptid. */
long
ptid_get_tid (ptid_t ptid)
{
return ptid.tid;
}
/* ptid_equal() is used to test equality of two ptids. */
int
ptid_equal (ptid_t ptid1, ptid_t ptid2)
{
return (ptid1.pid == ptid2.pid && ptid1.lwp == ptid2.lwp
&& ptid1.tid == ptid2.tid);
}
/* Returns true if PTID represents a process. */
int
ptid_is_pid (ptid_t ptid)
{
if (ptid_equal (minus_one_ptid, ptid))
return 0;
if (ptid_equal (null_ptid, ptid))
return 0;
return (ptid_get_lwp (ptid) == 0 && ptid_get_tid (ptid) == 0);
}
/* restore_inferior_ptid() will be used by the cleanup machinery
to restore the inferior_ptid value saved in a call to
save_inferior_ptid(). */
static void
restore_inferior_ptid (void *arg)
{
ptid_t *saved_ptid_ptr = arg;
inferior_ptid = *saved_ptid_ptr;
xfree (arg);
}
/* Save the value of inferior_ptid so that it may be restored by a
later call to do_cleanups(). Returns the struct cleanup pointer
needed for later doing the cleanup. */
struct cleanup *
save_inferior_ptid (void)
{
ptid_t *saved_ptid_ptr;
saved_ptid_ptr = xmalloc (sizeof (ptid_t));
*saved_ptid_ptr = inferior_ptid;
return make_cleanup (restore_inferior_ptid, saved_ptid_ptr);
}
/* User interface for reverse debugging:
Set exec-direction / show exec-direction commands
(returns error unless target implements to_set_exec_direction method). */
enum exec_direction_kind execution_direction = EXEC_FORWARD;
static const char exec_forward[] = "forward";
static const char exec_reverse[] = "reverse";
static const char *exec_direction = exec_forward;
static const char *exec_direction_names[] = {
exec_forward,
exec_reverse,
NULL
};
static void
set_exec_direction_func (char *args, int from_tty,
struct cmd_list_element *cmd)
{
if (target_can_execute_reverse)
{
if (!strcmp (exec_direction, exec_forward))
execution_direction = EXEC_FORWARD;
else if (!strcmp (exec_direction, exec_reverse))
execution_direction = EXEC_REVERSE;
}
}
static void
show_exec_direction_func (struct ui_file *out, int from_tty,
struct cmd_list_element *cmd, const char *value)
{
switch (execution_direction) {
case EXEC_FORWARD:
fprintf_filtered (out, _("Forward.\n"));
break;
case EXEC_REVERSE:
fprintf_filtered (out, _("Reverse.\n"));
break;
case EXEC_ERROR:
default:
fprintf_filtered (out,
_("Forward (target `%s' does not support exec-direction).\n"),
target_shortname);
break;
}
}
/* User interface for non-stop mode. */
int non_stop = 0;
static int non_stop_1 = 0;
static void
set_non_stop (char *args, int from_tty,
struct cmd_list_element *c)
{
if (target_has_execution)
{
non_stop_1 = non_stop;
error (_("Cannot change this setting while the inferior is running."));
}
non_stop = non_stop_1;
}
static void
show_non_stop (struct ui_file *file, int from_tty,
struct cmd_list_element *c, const char *value)
{
fprintf_filtered (file,
_("Controlling the inferior in non-stop mode is %s.\n"),
value);
}
void
_initialize_infrun (void)
{
int i;
int numsigs;
struct cmd_list_element *c;
add_info ("signals", signals_info, _("\
What debugger does when program gets various signals.\n\
Specify a signal as argument to print info on that signal only."));
add_info_alias ("handle", "signals", 0);
add_com ("handle", class_run, handle_command, _("\
Specify how to handle a signal.\n\
Args are signals and actions to apply to those signals.\n\
Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
from 1-15 are allowed for compatibility with old versions of GDB.\n\
Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
The special arg \"all\" is recognized to mean all signals except those\n\
used by the debugger, typically SIGTRAP and SIGINT.\n\
Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
\"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
Stop means reenter debugger if this signal happens (implies print).\n\
Print means print a message if this signal happens.\n\
Pass means let program see this signal; otherwise program doesn't know.\n\
Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
Pass and Stop may be combined."));
if (xdb_commands)
{
add_com ("lz", class_info, signals_info, _("\
What debugger does when program gets various signals.\n\
Specify a signal as argument to print info on that signal only."));
add_com ("z", class_run, xdb_handle_command, _("\
Specify how to handle a signal.\n\
Args are signals and actions to apply to those signals.\n\
Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
from 1-15 are allowed for compatibility with old versions of GDB.\n\
Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
The special arg \"all\" is recognized to mean all signals except those\n\
used by the debugger, typically SIGTRAP and SIGINT.\n\
Recognized actions include \"s\" (toggles between stop and nostop), \n\
\"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
nopass), \"Q\" (noprint)\n\
Stop means reenter debugger if this signal happens (implies print).\n\
Print means print a message if this signal happens.\n\
Pass means let program see this signal; otherwise program doesn't know.\n\
Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
Pass and Stop may be combined."));
}
if (!dbx_commands)
stop_command = add_cmd ("stop", class_obscure,
not_just_help_class_command, _("\
There is no `stop' command, but you can set a hook on `stop'.\n\
This allows you to set a list of commands to be run each time execution\n\
of the program stops."), &cmdlist);
add_setshow_zinteger_cmd ("infrun", class_maintenance, &debug_infrun, _("\
Set inferior debugging."), _("\
Show inferior debugging."), _("\
When non-zero, inferior specific debugging is enabled."),
NULL,
show_debug_infrun,
&setdebuglist, &showdebuglist);
add_setshow_boolean_cmd ("displaced", class_maintenance, &debug_displaced, _("\
Set displaced stepping debugging."), _("\
Show displaced stepping debugging."), _("\
When non-zero, displaced stepping specific debugging is enabled."),
NULL,
show_debug_displaced,
&setdebuglist, &showdebuglist);
add_setshow_boolean_cmd ("non-stop", no_class,
&non_stop_1, _("\
Set whether gdb controls the inferior in non-stop mode."), _("\
Show whether gdb controls the inferior in non-stop mode."), _("\
When debugging a multi-threaded program and this setting is\n\
off (the default, also called all-stop mode), when one thread stops\n\
(for a breakpoint, watchpoint, exception, or similar events), GDB stops\n\
all other threads in the program while you interact with the thread of\n\
interest. When you continue or step a thread, you can allow the other\n\
threads to run, or have them remain stopped, but while you inspect any\n\
thread's state, all threads stop.\n\
\n\
In non-stop mode, when one thread stops, other threads can continue\n\
to run freely. You'll be able to step each thread independently,\n\
leave it stopped or free to run as needed."),
set_non_stop,
show_non_stop,
&setlist,
&showlist);
numsigs = (int) TARGET_SIGNAL_LAST;
signal_stop = (unsigned char *) xmalloc (sizeof (signal_stop[0]) * numsigs);
signal_print = (unsigned char *)
xmalloc (sizeof (signal_print[0]) * numsigs);
signal_program = (unsigned char *)
xmalloc (sizeof (signal_program[0]) * numsigs);
for (i = 0; i < numsigs; i++)
{
signal_stop[i] = 1;
signal_print[i] = 1;
signal_program[i] = 1;
}
/* Signals caused by debugger's own actions
should not be given to the program afterwards. */
signal_program[TARGET_SIGNAL_TRAP] = 0;
signal_program[TARGET_SIGNAL_INT] = 0;
/* Signals that are not errors should not normally enter the debugger. */
signal_stop[TARGET_SIGNAL_ALRM] = 0;
signal_print[TARGET_SIGNAL_ALRM] = 0;
signal_stop[TARGET_SIGNAL_VTALRM] = 0;
signal_print[TARGET_SIGNAL_VTALRM] = 0;
signal_stop[TARGET_SIGNAL_PROF] = 0;
signal_print[TARGET_SIGNAL_PROF] = 0;
signal_stop[TARGET_SIGNAL_CHLD] = 0;
signal_print[TARGET_SIGNAL_CHLD] = 0;
signal_stop[TARGET_SIGNAL_IO] = 0;
signal_print[TARGET_SIGNAL_IO] = 0;
signal_stop[TARGET_SIGNAL_POLL] = 0;
signal_print[TARGET_SIGNAL_POLL] = 0;
signal_stop[TARGET_SIGNAL_URG] = 0;
signal_print[TARGET_SIGNAL_URG] = 0;
signal_stop[TARGET_SIGNAL_WINCH] = 0;
signal_print[TARGET_SIGNAL_WINCH] = 0;
/* These signals are used internally by user-level thread
implementations. (See signal(5) on Solaris.) Like the above
signals, a healthy program receives and handles them as part of
its normal operation. */
signal_stop[TARGET_SIGNAL_LWP] = 0;
signal_print[TARGET_SIGNAL_LWP] = 0;
signal_stop[TARGET_SIGNAL_WAITING] = 0;
signal_print[TARGET_SIGNAL_WAITING] = 0;
signal_stop[TARGET_SIGNAL_CANCEL] = 0;
signal_print[TARGET_SIGNAL_CANCEL] = 0;
add_setshow_zinteger_cmd ("stop-on-solib-events", class_support,
&stop_on_solib_events, _("\
Set stopping for shared library events."), _("\
Show stopping for shared library events."), _("\
If nonzero, gdb will give control to the user when the dynamic linker\n\
notifies gdb of shared library events. The most common event of interest\n\
to the user would be loading/unloading of a new library."),
NULL,
show_stop_on_solib_events,
&setlist, &showlist);
add_setshow_enum_cmd ("follow-fork-mode", class_run,
follow_fork_mode_kind_names,
&follow_fork_mode_string, _("\
Set debugger response to a program call of fork or vfork."), _("\
Show debugger response to a program call of fork or vfork."), _("\
A fork or vfork creates a new process. follow-fork-mode can be:\n\
parent - the original process is debugged after a fork\n\
child - the new process is debugged after a fork\n\
The unfollowed process will continue to run.\n\
By default, the debugger will follow the parent process."),
NULL,
show_follow_fork_mode_string,
&setlist, &showlist);
add_setshow_enum_cmd ("scheduler-locking", class_run,
scheduler_enums, &scheduler_mode, _("\
Set mode for locking scheduler during execution."), _("\
Show mode for locking scheduler during execution."), _("\
off == no locking (threads may preempt at any time)\n\
on == full locking (no thread except the current thread may run)\n\
step == scheduler locked during every single-step operation.\n\
In this mode, no other thread may run during a step command.\n\
Other threads may run while stepping over a function call ('next')."),
set_schedlock_func, /* traps on target vector */
show_scheduler_mode,
&setlist, &showlist);
add_setshow_boolean_cmd ("step-mode", class_run, &step_stop_if_no_debug, _("\
Set mode of the step operation."), _("\
Show mode of the step operation."), _("\
When set, doing a step over a function without debug line information\n\
will stop at the first instruction of that function. Otherwise, the\n\
function is skipped and the step command stops at a different source line."),
NULL,
show_step_stop_if_no_debug,
&setlist, &showlist);
add_setshow_enum_cmd ("displaced-stepping", class_run,
can_use_displaced_stepping_enum,
&can_use_displaced_stepping, _("\
Set debugger's willingness to use displaced stepping."), _("\
Show debugger's willingness to use displaced stepping."), _("\
If on, gdb will use displaced stepping to step over breakpoints if it is\n\
supported by the target architecture. If off, gdb will not use displaced\n\
stepping to step over breakpoints, even if such is supported by the target\n\
architecture. If auto (which is the default), gdb will use displaced stepping\n\
if the target architecture supports it and non-stop mode is active, but will not\n\
use it in all-stop mode (see help set non-stop)."),
NULL,
show_can_use_displaced_stepping,
&setlist, &showlist);
add_setshow_enum_cmd ("exec-direction", class_run, exec_direction_names,
&exec_direction, _("Set direction of execution.\n\
Options are 'forward' or 'reverse'."),
_("Show direction of execution (forward/reverse)."),
_("Tells gdb whether to execute forward or backward."),
set_exec_direction_func, show_exec_direction_func,
&setlist, &showlist);
/* ptid initializations */
null_ptid = ptid_build (0, 0, 0);
minus_one_ptid = ptid_build (-1, 0, 0);
inferior_ptid = null_ptid;
target_last_wait_ptid = minus_one_ptid;
displaced_step_ptid = null_ptid;
observer_attach_thread_ptid_changed (infrun_thread_ptid_changed);
observer_attach_thread_stop_requested (infrun_thread_stop_requested);
}
|