aboutsummaryrefslogtreecommitdiff
path: root/gdb/target.c
blob: a9217d887b27e7618c38a69816b02d0550669883 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
1022
1023
1024
1025
1026
1027
1028
1029
1030
1031
1032
1033
1034
1035
1036
1037
1038
1039
1040
1041
1042
1043
1044
1045
1046
1047
1048
1049
1050
1051
1052
1053
1054
1055
1056
1057
1058
1059
1060
1061
1062
1063
1064
1065
1066
1067
1068
1069
1070
1071
1072
1073
1074
1075
1076
1077
1078
1079
1080
1081
1082
1083
1084
1085
1086
1087
1088
1089
1090
1091
1092
1093
1094
1095
1096
1097
1098
1099
1100
1101
1102
1103
1104
1105
1106
1107
1108
1109
1110
1111
1112
1113
1114
1115
1116
1117
1118
1119
1120
1121
1122
1123
1124
1125
1126
1127
1128
1129
1130
1131
1132
1133
1134
1135
1136
1137
1138
1139
1140
1141
1142
1143
1144
1145
1146
1147
1148
1149
1150
1151
1152
1153
1154
1155
1156
1157
1158
1159
1160
1161
1162
1163
1164
1165
1166
1167
1168
1169
1170
1171
1172
1173
1174
1175
1176
1177
1178
1179
1180
1181
1182
1183
1184
1185
1186
1187
1188
1189
1190
1191
1192
1193
1194
1195
1196
1197
1198
1199
1200
1201
1202
1203
1204
1205
1206
1207
1208
1209
1210
1211
1212
1213
1214
1215
1216
1217
1218
1219
1220
1221
1222
1223
1224
1225
1226
1227
1228
1229
1230
1231
1232
1233
1234
1235
1236
1237
1238
1239
1240
1241
1242
1243
1244
1245
1246
1247
1248
1249
1250
1251
1252
1253
1254
1255
1256
1257
1258
1259
1260
1261
1262
1263
1264
1265
1266
1267
1268
1269
1270
1271
1272
1273
1274
1275
1276
1277
1278
1279
1280
1281
1282
1283
1284
1285
1286
1287
1288
1289
1290
1291
1292
1293
1294
1295
1296
1297
1298
1299
1300
1301
1302
1303
1304
1305
1306
1307
1308
1309
1310
1311
1312
1313
1314
1315
1316
1317
1318
1319
1320
1321
1322
1323
1324
1325
1326
1327
1328
1329
1330
1331
1332
1333
1334
1335
1336
1337
1338
1339
1340
1341
1342
1343
1344
1345
1346
1347
1348
1349
1350
1351
1352
1353
1354
1355
1356
1357
1358
1359
1360
1361
1362
1363
1364
1365
1366
1367
1368
1369
1370
1371
1372
1373
1374
1375
1376
1377
1378
1379
1380
1381
1382
1383
1384
1385
1386
1387
1388
1389
1390
1391
1392
1393
1394
1395
1396
1397
1398
1399
1400
1401
1402
1403
1404
1405
1406
1407
1408
1409
1410
1411
1412
1413
1414
1415
1416
1417
1418
1419
1420
1421
1422
1423
1424
1425
1426
1427
1428
1429
1430
1431
1432
1433
1434
1435
1436
1437
1438
1439
1440
1441
1442
1443
1444
1445
1446
1447
1448
1449
1450
1451
1452
1453
1454
1455
1456
1457
1458
1459
1460
1461
1462
1463
1464
1465
1466
1467
1468
1469
1470
1471
1472
1473
1474
1475
1476
1477
1478
1479
1480
1481
1482
1483
1484
1485
1486
1487
1488
1489
1490
1491
1492
1493
1494
1495
1496
1497
1498
1499
1500
1501
1502
1503
1504
1505
1506
1507
1508
1509
1510
1511
1512
1513
1514
1515
1516
1517
1518
1519
1520
1521
1522
1523
1524
1525
1526
1527
1528
1529
1530
1531
1532
1533
1534
1535
1536
1537
1538
1539
1540
1541
1542
1543
1544
1545
1546
1547
1548
1549
1550
1551
1552
1553
1554
1555
1556
1557
1558
1559
1560
1561
1562
1563
1564
1565
1566
1567
1568
1569
1570
1571
1572
1573
1574
1575
1576
1577
1578
1579
1580
1581
1582
1583
1584
1585
1586
1587
1588
1589
1590
1591
1592
1593
1594
1595
1596
1597
1598
1599
1600
1601
1602
1603
1604
1605
1606
1607
1608
1609
1610
1611
1612
1613
1614
1615
1616
1617
1618
1619
1620
1621
1622
1623
1624
1625
1626
1627
1628
1629
1630
1631
1632
1633
1634
1635
1636
1637
1638
1639
1640
1641
1642
1643
1644
1645
1646
1647
1648
1649
1650
1651
1652
1653
1654
1655
1656
1657
1658
1659
1660
1661
1662
1663
1664
1665
1666
1667
1668
1669
1670
1671
1672
1673
1674
1675
1676
1677
1678
1679
1680
1681
1682
1683
1684
1685
1686
1687
1688
1689
1690
1691
1692
1693
1694
1695
1696
1697
1698
1699
1700
1701
1702
1703
1704
1705
1706
1707
1708
1709
1710
1711
1712
1713
1714
1715
1716
1717
1718
1719
1720
1721
1722
1723
1724
1725
1726
1727
1728
1729
1730
1731
1732
1733
1734
1735
1736
1737
1738
1739
1740
1741
1742
1743
1744
1745
1746
1747
1748
1749
1750
1751
1752
1753
1754
1755
1756
1757
1758
1759
1760
1761
1762
1763
1764
1765
1766
1767
1768
1769
1770
1771
1772
1773
1774
1775
1776
1777
1778
1779
1780
1781
1782
1783
1784
1785
1786
1787
1788
1789
1790
1791
1792
1793
1794
1795
1796
1797
1798
1799
1800
1801
1802
1803
1804
1805
1806
1807
1808
1809
1810
1811
1812
1813
1814
1815
1816
1817
1818
1819
1820
1821
1822
1823
1824
1825
1826
1827
1828
1829
1830
1831
1832
1833
1834
1835
1836
1837
1838
1839
1840
1841
1842
1843
1844
1845
1846
1847
1848
1849
1850
1851
1852
1853
1854
1855
1856
1857
1858
1859
1860
1861
1862
1863
1864
1865
1866
1867
1868
1869
1870
1871
1872
1873
1874
1875
1876
1877
1878
1879
1880
1881
1882
1883
1884
1885
1886
1887
1888
1889
1890
1891
1892
1893
1894
1895
1896
1897
1898
1899
1900
1901
1902
1903
1904
1905
1906
1907
1908
1909
1910
1911
1912
1913
1914
1915
1916
1917
1918
1919
1920
1921
1922
1923
1924
1925
1926
1927
1928
1929
1930
1931
1932
1933
1934
1935
1936
1937
1938
1939
1940
1941
1942
1943
1944
1945
1946
1947
1948
1949
1950
1951
1952
1953
1954
1955
1956
1957
1958
1959
1960
1961
1962
1963
1964
1965
1966
1967
1968
1969
1970
1971
1972
1973
1974
1975
1976
1977
1978
1979
1980
1981
1982
1983
1984
1985
1986
1987
1988
1989
1990
1991
1992
1993
1994
1995
1996
1997
1998
1999
2000
2001
2002
2003
2004
2005
2006
2007
2008
2009
2010
2011
2012
2013
2014
2015
2016
2017
2018
2019
2020
2021
2022
2023
2024
2025
2026
2027
2028
2029
2030
2031
2032
2033
2034
2035
2036
2037
2038
2039
2040
2041
2042
2043
2044
2045
2046
2047
2048
2049
2050
2051
2052
2053
2054
2055
2056
2057
2058
2059
2060
2061
2062
2063
2064
2065
2066
2067
2068
2069
2070
2071
2072
2073
2074
2075
2076
2077
2078
2079
2080
2081
2082
2083
2084
2085
2086
2087
2088
2089
2090
2091
2092
2093
2094
2095
2096
2097
2098
2099
2100
2101
2102
2103
2104
2105
2106
2107
2108
2109
2110
2111
2112
2113
2114
2115
2116
2117
2118
2119
2120
2121
2122
2123
2124
2125
2126
2127
2128
2129
2130
2131
2132
2133
2134
2135
2136
2137
2138
2139
2140
2141
2142
2143
2144
2145
2146
2147
2148
2149
2150
2151
2152
2153
2154
2155
2156
2157
2158
2159
2160
2161
2162
2163
2164
2165
2166
2167
2168
2169
2170
2171
2172
2173
2174
2175
2176
2177
2178
2179
2180
2181
2182
2183
2184
2185
2186
2187
2188
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
/* Select target systems and architectures at runtime for GDB.
   Copyright 1990, 1992-1995, 1998, 1999 Free Software Foundation, Inc.
   Contributed by Cygnus Support.

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 2 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */

#include "defs.h"
#include <errno.h>
#include <ctype.h>
#include "gdb_string.h"
#include "target.h"
#include "gdbcmd.h"
#include "symtab.h"
#include "inferior.h"
#include "bfd.h"
#include "symfile.h"
#include "objfiles.h"
#include "wait.h"
#include <signal.h>

extern int errno;

static void
target_info PARAMS ((char *, int));

static void
cleanup_target PARAMS ((struct target_ops *));

static void
maybe_kill_then_create_inferior PARAMS ((char *, char *, char **));

static void
default_clone_and_follow_inferior PARAMS ((int, int *));

static void
maybe_kill_then_attach PARAMS ((char *, int));

static void
kill_or_be_killed PARAMS ((int));

static void
default_terminal_info PARAMS ((char *, int));

static int
nosymbol PARAMS ((char *, CORE_ADDR *));

static void
tcomplain PARAMS ((void));

static int
nomemory PARAMS ((CORE_ADDR, char *, int, int, struct target_ops *));

static int
return_zero PARAMS ((void));

static int
return_one PARAMS ((void));

void
target_ignore PARAMS ((void));

static void
target_command PARAMS ((char *, int));

static struct target_ops *
find_default_run_target PARAMS ((char *));

static void
update_current_target PARAMS ((void));

static void nosupport_runtime PARAMS ((void));

static void normal_target_post_startup_inferior PARAMS ((int pid));

/* Transfer LEN bytes between target address MEMADDR and GDB address MYADDR.
   Returns 0 for success, errno code for failure (which includes partial
   transfers--if you want a more useful response to partial transfers, try
   target_read_memory_partial).  */

static int
target_xfer_memory PARAMS ((CORE_ADDR memaddr, char *myaddr, int len,
			    int write, asection *bfd_section));

static void init_dummy_target PARAMS ((void));

static void
debug_to_open PARAMS ((char *, int));

static void
debug_to_close PARAMS ((int));

static void
debug_to_attach PARAMS ((char *, int));

static void
debug_to_detach PARAMS ((char *, int));

static void
debug_to_resume PARAMS ((int, int, enum target_signal));

static int
debug_to_wait PARAMS ((int, struct target_waitstatus *));

static void
debug_to_fetch_registers PARAMS ((int));

static void
debug_to_store_registers PARAMS ((int));

static void
debug_to_prepare_to_store PARAMS ((void));

static int
debug_to_xfer_memory PARAMS ((CORE_ADDR, char *, int, int, struct target_ops *));

static void
debug_to_files_info PARAMS ((struct target_ops *));

static int
debug_to_insert_breakpoint PARAMS ((CORE_ADDR, char *));

static int
debug_to_remove_breakpoint PARAMS ((CORE_ADDR, char *));

static void
debug_to_terminal_init PARAMS ((void));

static void
debug_to_terminal_inferior PARAMS ((void));

static void
debug_to_terminal_ours_for_output PARAMS ((void));

static void
debug_to_terminal_ours PARAMS ((void));

static void
debug_to_terminal_info PARAMS ((char *, int));

static void
debug_to_kill PARAMS ((void));

static void
debug_to_load PARAMS ((char *, int));

static int
debug_to_lookup_symbol PARAMS ((char *, CORE_ADDR *));

static void
debug_to_create_inferior PARAMS ((char *, char *, char **));

static void
debug_to_mourn_inferior PARAMS ((void));

static int
debug_to_can_run PARAMS ((void));

static void
debug_to_notice_signals PARAMS ((int));

static int
debug_to_thread_alive PARAMS ((int));

static void
debug_to_stop PARAMS ((void));

static int debug_to_query PARAMS ((int/*char*/, char *, char *, int *));

/* Pointer to array of target architecture structures; the size of the
   array; the current index into the array; the allocated size of the 
   array.  */
struct target_ops **target_structs;
unsigned target_struct_size;
unsigned target_struct_index;
unsigned target_struct_allocsize;
#define	DEFAULT_ALLOCSIZE	10

/* The initial current target, so that there is always a semi-valid
   current target.  */

static struct target_ops dummy_target;

/* Top of target stack.  */

struct target_stack_item *target_stack;

/* The target structure we are currently using to talk to a process
   or file or whatever "inferior" we have.  */

struct target_ops current_target;

/* Command list for target.  */

static struct cmd_list_element *targetlist = NULL;

/* Nonzero if we are debugging an attached outside process
   rather than an inferior.  */

int attach_flag;

/* Non-zero if we want to see trace of target level stuff.  */

static int targetdebug = 0;

static void setup_target_debug PARAMS ((void));

/* The user just typed 'target' without the name of a target.  */

/* ARGSUSED */
static void
target_command (arg, from_tty)
     char *arg;
     int from_tty;
{
  fputs_filtered ("Argument required (target name).  Try `help target'\n",
		  gdb_stdout);
}

/* Add a possible target architecture to the list.  */

void
add_target (t)
     struct target_ops *t;
{
  if (!target_structs)
    {
      target_struct_allocsize = DEFAULT_ALLOCSIZE;
      target_structs = (struct target_ops **) xmalloc
	(target_struct_allocsize * sizeof (*target_structs));
    }
  if (target_struct_size >= target_struct_allocsize)
    {
      target_struct_allocsize *= 2;
      target_structs = (struct target_ops **)
	  xrealloc ((char *) target_structs, 
		    target_struct_allocsize * sizeof (*target_structs));
    }
  target_structs[target_struct_size++] = t;
/*  cleanup_target (t);*/

  if (targetlist == NULL)
    add_prefix_cmd ("target", class_run, target_command,
		    "Connect to a target machine or process.\n\
The first argument is the type or protocol of the target machine.\n\
Remaining arguments are interpreted by the target protocol.  For more\n\
information on the arguments for a particular protocol, type\n\
`help target ' followed by the protocol name.",
		    &targetlist, "target ", 0, &cmdlist);
  add_cmd (t->to_shortname, no_class, t->to_open, t->to_doc, &targetlist);
}

/* Stub functions */

void
target_ignore ()
{
}

/* ARGSUSED */
static int
nomemory (memaddr, myaddr, len, write, t)
     CORE_ADDR memaddr;
     char *myaddr;
     int len;
     int write;
     struct target_ops *t;
{
  errno = EIO;		/* Can't read/write this location */
  return 0;		/* No bytes handled */
}

static void
tcomplain ()
{
  error ("You can't do that when your target is `%s'",
	 current_target.to_shortname);
}

void
noprocess ()
{
  error ("You can't do that without a process to debug.");
}

/* ARGSUSED */
static int
nosymbol (name, addrp)
     char *name;
     CORE_ADDR *addrp;
{
  return 1;		/* Symbol does not exist in target env */
}

/* ARGSUSED */
static void
nosupport_runtime ()
{
  if (!inferior_pid)
    noprocess ();
  else
    error ("No run-time support for this");
}


/* ARGSUSED */
static void
default_terminal_info (args, from_tty)
     char *args;
     int from_tty;
{
  printf_unfiltered("No saved terminal information.\n");
}

/* This is the default target_create_inferior and target_attach function.
   If the current target is executing, it asks whether to kill it off.
   If this function returns without calling error(), it has killed off
   the target, and the operation should be attempted.  */

static void
kill_or_be_killed (from_tty)
     int from_tty;
{
  if (target_has_execution)
    {
      printf_unfiltered ("You are already running a program:\n");
      target_files_info ();
      if (query ("Kill it? ")) {
	target_kill ();
	if (target_has_execution)
	  error ("Killing the program did not help.");
	return;
      } else {
	error ("Program not killed.");
      }
    }
  tcomplain();
}

static void
maybe_kill_then_attach (args, from_tty)
     char *args;
     int from_tty;
{
  kill_or_be_killed (from_tty);
  target_attach (args, from_tty);
}

static void
maybe_kill_then_create_inferior (exec, args, env)
     char *exec;
     char *args;
     char **env;
{
  kill_or_be_killed (0);
  target_create_inferior (exec, args, env);
}

static void
default_clone_and_follow_inferior (child_pid, followed_child)
  int  child_pid;
  int  *followed_child;
{
  target_clone_and_follow_inferior (child_pid, followed_child);
}

/* Clean up a target struct so it no longer has any zero pointers in it.
   We default entries, at least to stubs that print error messages.  */

static void
cleanup_target (t)
     struct target_ops *t;
{

#define de_fault(field, value) \
  if (!t->field)	t->field = value

  /*        FIELD			DEFAULT VALUE        */

  de_fault (to_open, 			(void (*) PARAMS((char *, int))) tcomplain);
  de_fault (to_close, 			(void (*) PARAMS((int))) target_ignore);
  de_fault (to_attach, 			maybe_kill_then_attach);
  de_fault (to_post_attach,             (void (*) PARAMS ((int))) target_ignore);
  de_fault (to_require_attach,          maybe_kill_then_attach);
  de_fault (to_detach, 			(void (*) PARAMS((char *, int))) target_ignore);
  de_fault (to_require_detach,          (void (*) PARAMS((int, char *, int))) target_ignore);
  de_fault (to_resume, 			(void (*) PARAMS((int, int, enum target_signal))) noprocess);
  de_fault (to_wait, 			(int (*) PARAMS((int, struct target_waitstatus *))) noprocess);
  de_fault (to_post_wait,               (void (*) PARAMS ((int, int))) target_ignore);
  de_fault (to_fetch_registers, 	(void (*) PARAMS((int))) target_ignore);
  de_fault (to_store_registers,		(void (*) PARAMS((int))) noprocess);
  de_fault (to_prepare_to_store,	(void (*) PARAMS((void))) noprocess);
  de_fault (to_xfer_memory,		(int (*) PARAMS((CORE_ADDR, char *, int, int, struct target_ops *))) nomemory);
  de_fault (to_files_info,		(void (*) PARAMS((struct target_ops *))) target_ignore);
  de_fault (to_insert_breakpoint,	memory_insert_breakpoint);
  de_fault (to_remove_breakpoint,	memory_remove_breakpoint);
  de_fault (to_terminal_init,		(void (*) PARAMS((void))) target_ignore);
  de_fault (to_terminal_inferior,	(void (*) PARAMS ((void))) target_ignore);
  de_fault (to_terminal_ours_for_output,(void (*) PARAMS ((void))) target_ignore);
  de_fault (to_terminal_ours,		(void (*) PARAMS ((void))) target_ignore);
  de_fault (to_terminal_info,		default_terminal_info);
  de_fault (to_kill,			(void (*) PARAMS((void))) noprocess);
  de_fault (to_load,			(void (*) PARAMS((char *, int))) tcomplain);
  de_fault (to_lookup_symbol,		(int (*) PARAMS ((char *, CORE_ADDR *))) nosymbol);
  de_fault (to_create_inferior,		maybe_kill_then_create_inferior);
  de_fault (to_post_startup_inferior,   (void (*) PARAMS ((int))) target_ignore);
  de_fault (to_acknowledge_created_inferior,            (void (*) PARAMS((int))) target_ignore);
  de_fault (to_clone_and_follow_inferior,               default_clone_and_follow_inferior);
  de_fault (to_post_follow_inferior_by_clone,           (void (*) PARAMS ((void))) target_ignore);
  de_fault (to_insert_fork_catchpoint,  (int (*) PARAMS ((int))) tcomplain);
  de_fault (to_remove_fork_catchpoint,  (int (*) PARAMS ((int))) tcomplain);
  de_fault (to_insert_vfork_catchpoint, (int (*) PARAMS ((int))) tcomplain);
  de_fault (to_remove_vfork_catchpoint, (int (*) PARAMS ((int))) tcomplain);
  de_fault (to_has_forked,              (int (*) PARAMS ((int, int *))) return_zero);
  de_fault (to_has_vforked,             (int (*) PARAMS ((int, int *))) return_zero);
  de_fault (to_can_follow_vfork_prior_to_exec, (int (*) PARAMS ((void ))) return_zero);
  de_fault (to_post_follow_vfork,       (void (*) PARAMS ((int, int, int, int))) target_ignore);
  de_fault (to_insert_exec_catchpoint,  (int (*) PARAMS ((int))) tcomplain);
  de_fault (to_remove_exec_catchpoint,  (int (*) PARAMS ((int))) tcomplain);
  de_fault (to_has_execd,               (int (*) PARAMS ((int, char **))) return_zero);
  de_fault (to_reported_exec_events_per_exec_call, (int (*) PARAMS ((void))) return_one);
  de_fault (to_has_syscall_event,       (int (*) PARAMS ((int, enum target_waitkind *, int *))) return_zero);
  de_fault (to_has_exited,              (int (*) PARAMS ((int, int, int *))) return_zero);
  de_fault (to_mourn_inferior,		(void (*) PARAMS ((void))) noprocess);
  de_fault (to_can_run,			return_zero);
  de_fault (to_notice_signals,		(void (*) PARAMS((int))) target_ignore);
  de_fault (to_thread_alive,		(int (*) PARAMS((int))) target_ignore);
  de_fault (to_stop,			(void (*) PARAMS((void))) target_ignore);
  de_fault (to_query,			(int (*) PARAMS((int/*char*/, char*, char *, int *))) target_ignore);
  de_fault (to_enable_exception_callback,	(struct symtab_and_line * (*) PARAMS((enum exception_event_kind, int))) nosupport_runtime);
  de_fault (to_get_current_exception_event,	(struct exception_event_record * (*) PARAMS((void))) nosupport_runtime);

  de_fault (to_pid_to_exec_file,        (char* (*) PARAMS((int))) return_zero);
  de_fault (to_core_file_to_sym_file,   (char* (*) PARAMS ((char *))) return_zero);
#undef de_fault
}

/* Go through the target stack from top to bottom, copying over zero entries in
   current_target.  In effect, we are doing class inheritance through the
   pushed target vectors.  */

static void
update_current_target ()
{
  struct target_stack_item *item;
  struct target_ops *t;

  /* First, reset current_target */
  memset (&current_target, 0, sizeof current_target);

  for (item = target_stack; item; item = item->next)
    {
      t = item->target_ops;

#define INHERIT(FIELD, TARGET) \
      if (!current_target.FIELD) \
	current_target.FIELD = TARGET->FIELD

      INHERIT (to_shortname, t);
      INHERIT (to_longname, t);
      INHERIT (to_doc, t);
      INHERIT (to_open, t);
      INHERIT (to_close, t);
      INHERIT (to_attach, t);
      INHERIT (to_post_attach, t);
      INHERIT (to_require_attach, t);
      INHERIT (to_detach, t);
      INHERIT (to_require_detach, t);
      INHERIT (to_resume, t);
      INHERIT (to_wait, t);
      INHERIT (to_post_wait, t);
      INHERIT (to_fetch_registers, t);
      INHERIT (to_store_registers, t);
      INHERIT (to_prepare_to_store, t);
      INHERIT (to_xfer_memory, t);
      INHERIT (to_files_info, t);
      INHERIT (to_insert_breakpoint, t);
      INHERIT (to_remove_breakpoint, t);
      INHERIT (to_terminal_init, t);
      INHERIT (to_terminal_inferior, t);
      INHERIT (to_terminal_ours_for_output, t);
      INHERIT (to_terminal_ours, t);
      INHERIT (to_terminal_info, t);
      INHERIT (to_kill, t);
      INHERIT (to_load, t);
      INHERIT (to_lookup_symbol, t);
      INHERIT (to_create_inferior, t);
      INHERIT (to_post_startup_inferior, t);
      INHERIT (to_acknowledge_created_inferior, t);
      INHERIT (to_clone_and_follow_inferior, t);
      INHERIT (to_post_follow_inferior_by_clone, t);
      INHERIT (to_insert_fork_catchpoint, t);
      INHERIT (to_remove_fork_catchpoint, t);
      INHERIT (to_insert_vfork_catchpoint, t);
      INHERIT (to_remove_vfork_catchpoint, t);
      INHERIT (to_has_forked, t);
      INHERIT (to_has_vforked, t);
      INHERIT (to_can_follow_vfork_prior_to_exec, t);
      INHERIT (to_post_follow_vfork, t);
      INHERIT (to_insert_exec_catchpoint, t);
      INHERIT (to_remove_exec_catchpoint, t);
      INHERIT (to_has_execd, t);
      INHERIT (to_reported_exec_events_per_exec_call, t);
      INHERIT (to_has_syscall_event, t);
      INHERIT (to_has_exited, t);
      INHERIT (to_mourn_inferior, t);
      INHERIT (to_can_run, t);
      INHERIT (to_notice_signals, t);
      INHERIT (to_thread_alive, t);
      INHERIT (to_find_new_threads, t);
      INHERIT (to_stop, t);
      INHERIT (to_query, t);
      INHERIT (to_enable_exception_callback, t);
      INHERIT (to_get_current_exception_event, t);
      INHERIT (to_pid_to_exec_file, t);
      INHERIT (to_core_file_to_sym_file, t);
      INHERIT (to_stratum, t);
      INHERIT (DONT_USE, t);
      INHERIT (to_has_all_memory, t);
      INHERIT (to_has_memory, t);
      INHERIT (to_has_stack, t);
      INHERIT (to_has_registers, t);
      INHERIT (to_has_execution, t);
      INHERIT (to_has_thread_control, t);
      INHERIT (to_has_async_exec, t);
      INHERIT (to_sections, t);
      INHERIT (to_sections_end, t);
      INHERIT (to_magic, t);

#undef INHERIT
    }
}

/* Push a new target type into the stack of the existing target accessors,
   possibly superseding some of the existing accessors.

   Result is zero if the pushed target ended up on top of the stack,
   nonzero if at least one target is on top of it.

   Rather than allow an empty stack, we always have the dummy target at
   the bottom stratum, so we can call the function vectors without
   checking them.  */

int
push_target (t)
     struct target_ops *t;
{
  struct target_stack_item *cur, *prev, *tmp;

  /* Check magic number.  If wrong, it probably means someone changed
     the struct definition, but not all the places that initialize one.  */
  if (t->to_magic != OPS_MAGIC)
    {
      fprintf_unfiltered(gdb_stderr,
			 "Magic number of %s target struct wrong\n", 
			 t->to_shortname);
      abort();
    }

  /* Find the proper stratum to install this target in. */

  for (prev = NULL, cur = target_stack; cur; prev = cur, cur = cur->next)
    {
      if ((int)(t->to_stratum) >= (int)(cur->target_ops->to_stratum))
	break;
    }

  /* If there's already targets at this stratum, remove them. */

  if (cur)
    while (t->to_stratum == cur->target_ops->to_stratum)
      {
	/* There's already something on this stratum.  Close it off.  */
	if (cur->target_ops->to_close)
	  (cur->target_ops->to_close) (0);
	if (prev)
	  prev->next = cur->next; /* Unchain old target_ops */
	else
	  target_stack = cur->next; /* Unchain first on list */
	tmp = cur->next;
	free (cur);
	cur = tmp;
      }

  /* We have removed all targets in our stratum, now add the new one.  */

  tmp = (struct target_stack_item *)
    xmalloc (sizeof (struct target_stack_item));
  tmp->next = cur;
  tmp->target_ops = t;

  if (prev)
    prev->next = tmp;
  else
    target_stack = tmp;

  update_current_target ();

  cleanup_target (&current_target); /* Fill in the gaps */

  if (targetdebug)
    setup_target_debug ();

  return prev != 0;
}

/* Remove a target_ops vector from the stack, wherever it may be. 
   Return how many times it was removed (0 or 1).  */

int
unpush_target (t)
     struct target_ops *t;
{
  struct target_stack_item *cur, *prev;

  if (t->to_close)
    t->to_close (0);		/* Let it clean up */

  /* Look for the specified target.  Note that we assume that a target
     can only occur once in the target stack. */

  for (cur = target_stack, prev = NULL; cur; prev = cur, cur = cur->next)
    if (cur->target_ops == t)
      break;

  if (!cur)
    return 0;			/* Didn't find target_ops, quit now */

  /* Unchain the target */

  if (!prev)
    target_stack = cur->next;
  else
    prev->next = cur->next;

  free (cur);			/* Release the target_stack_item */

  update_current_target ();
  cleanup_target (&current_target);

  return 1;
}

void
pop_target ()
{
  (current_target.to_close)(0);	/* Let it clean up */
  if (unpush_target (target_stack->target_ops) == 1)
    return;

  fprintf_unfiltered(gdb_stderr,
		     "pop_target couldn't find target %s\n", 
		     current_target.to_shortname);
  abort();
}

#undef	MIN
#define MIN(A, B) (((A) <= (B)) ? (A) : (B))

/* target_read_string -- read a null terminated string, up to LEN bytes,
   from MEMADDR in target.  Set *ERRNOP to the errno code, or 0 if successful.
   Set *STRING to a pointer to malloc'd memory containing the data; the caller
   is responsible for freeing it.  Return the number of bytes successfully
   read.  */

int
target_read_string (memaddr, string, len, errnop)
     CORE_ADDR memaddr;
     char **string;
     int len;
     int *errnop;
{
  int tlen, origlen, offset, i;
  char buf[4];
  int errcode = 0;
  char *buffer;
  int buffer_allocated;
  char *bufptr;
  unsigned int nbytes_read = 0;

  /* Small for testing.  */
  buffer_allocated = 4;
  buffer = xmalloc (buffer_allocated);
  bufptr = buffer;

  origlen = len;

  while (len > 0)
    {
      tlen = MIN (len, 4 - (memaddr & 3));
      offset = memaddr & 3;

      errcode = target_xfer_memory (memaddr & ~3, buf, 4, 0, NULL);
      if (errcode != 0)
	{
	  /* The transfer request might have crossed the boundary to an
	     unallocated region of memory. Retry the transfer, requesting
	     a single byte.  */
	  tlen = 1;
	  offset = 0;
	  errcode = target_xfer_memory (memaddr, buf, 1, 0, NULL);
	  if (errcode != 0)
	    goto done;
	}

      if (bufptr - buffer + tlen > buffer_allocated)
	{
	  unsigned int bytes;
	  bytes = bufptr - buffer;
	  buffer_allocated *= 2;
	  buffer = xrealloc (buffer, buffer_allocated);
	  bufptr = buffer + bytes;
	}

      for (i = 0; i < tlen; i++)
	{
	  *bufptr++ = buf[i + offset];
	  if (buf[i + offset] == '\000')
	    {
	      nbytes_read += i + 1;
	      goto done;
	    }
	}

      memaddr += tlen;
      len -= tlen;
      nbytes_read += tlen;
    }
 done:
  if (errnop != NULL)
    *errnop = errcode;
  if (string != NULL)
    *string = buffer;
  return nbytes_read;
}

/* Read LEN bytes of target memory at address MEMADDR, placing the results in
   GDB's memory at MYADDR.  Returns either 0 for success or an errno value
   if any error occurs.

   If an error occurs, no guarantee is made about the contents of the data at
   MYADDR.  In particular, the caller should not depend upon partial reads
   filling the buffer with good data.  There is no way for the caller to know
   how much good data might have been transfered anyway.  Callers that can
   deal with partial reads should call target_read_memory_partial. */

int
target_read_memory (memaddr, myaddr, len)
     CORE_ADDR memaddr;
     char *myaddr;
     int len;
{
  return target_xfer_memory (memaddr, myaddr, len, 0, NULL);
}

int
target_read_memory_section (memaddr, myaddr, len, bfd_section)
     CORE_ADDR memaddr;
     char *myaddr;
     int len;
     asection *bfd_section;
{
  return target_xfer_memory (memaddr, myaddr, len, 0, bfd_section);
}

/* Read LEN bytes of target memory at address MEMADDR, placing the results
   in GDB's memory at MYADDR.  Returns a count of the bytes actually read,
   and optionally an errno value in the location pointed to by ERRNOPTR
   if ERRNOPTR is non-null. */

int
target_read_memory_partial (memaddr, myaddr, len, errnoptr)
     CORE_ADDR memaddr;
     char *myaddr;
     int len;
     int *errnoptr;
{
  int nread;	/* Number of bytes actually read. */
  int errcode;	/* Error from last read. */

  /* First try a complete read. */
  errcode = target_xfer_memory (memaddr, myaddr, len, 0, NULL);
  if (errcode == 0)
    {
      /* Got it all. */
      nread = len;
    }
  else
    {
      /* Loop, reading one byte at a time until we get as much as we can. */
      for (errcode = 0, nread = 0; len > 0 && errcode == 0; nread++, len--)
	{
	  errcode = target_xfer_memory (memaddr++, myaddr++, 1, 0, NULL);
	}
      /* If an error, the last read was unsuccessful, so adjust count. */
      if (errcode != 0)
	{
	  nread--;
	}
    }
  if (errnoptr != NULL)
    {
      *errnoptr = errcode;
    }
  return (nread);
}

int
target_write_memory (memaddr, myaddr, len)
     CORE_ADDR memaddr;
     char *myaddr;
     int len;
{
  return target_xfer_memory (memaddr, myaddr, len, 1, NULL);
}
 
/* This variable is used to pass section information down to targets.  This
   *should* be done by adding an argument to the target_xfer_memory function
   of all the targets, but I didn't feel like changing 50+ files.  */

asection *target_memory_bfd_section = NULL;

/* Move memory to or from the targets.  Iterate until all of it has
   been moved, if necessary.  The top target gets priority; anything
   it doesn't want, is offered to the next one down, etc.  Note the
   business with curlen:  if an early target says "no, but I have a
   boundary overlapping this xfer" then we shorten what we offer to
   the subsequent targets so the early guy will get a chance at the
   tail before the subsequent ones do. 

   Result is 0 or errno value.  */

static int
target_xfer_memory (memaddr, myaddr, len, write, bfd_section)
     CORE_ADDR memaddr;
     char *myaddr;
     int len;
     int write;
     asection *bfd_section;
{
  int curlen;
  int res;
  struct target_ops *t;
  struct target_stack_item *item;

  /* Zero length requests are ok and require no work.  */
  if (len == 0)
    return 0;

  target_memory_bfd_section = bfd_section;

  /* to_xfer_memory is not guaranteed to set errno, even when it returns
     0.  */
  errno = 0;

  /* The quick case is that the top target does it all.  */
  res = current_target.to_xfer_memory
			(memaddr, myaddr, len, write, &current_target);
  if (res == len)
    return 0;

  if (res > 0)
    goto bump;
  /* If res <= 0 then we call it again in the loop.  Ah well.  */

  for (; len > 0;)
    {
      curlen = len;		/* Want to do it all */
      for (item = target_stack; item; item = item->next)
	{
	  t = item->target_ops;
	  if (!t->to_has_memory)
	    continue;

	  res = t->to_xfer_memory (memaddr, myaddr, curlen, write, t);
	  if (res > 0)
	    break;		/* Handled all or part of xfer */
	  if (t->to_has_all_memory)
	    break;
	}

      if (res <= 0)
	{
	  /* If this address is for nonexistent memory,
	     read zeros if reading, or do nothing if writing.  Return error. */
	  if (!write)
	    memset (myaddr, 0, len);
	  if (errno == 0)
	    return EIO;
	  else
	    return errno;
	}
bump:
      memaddr += res;
      myaddr  += res;
      len     -= res;
    }
  return 0;			/* We managed to cover it all somehow. */
}


/* ARGSUSED */
static void
target_info (args, from_tty)
     char *args;
     int from_tty;
{
  struct target_ops *t;
  struct target_stack_item *item;
  int has_all_mem = 0;
  
  if (symfile_objfile != NULL)
    printf_unfiltered ("Symbols from \"%s\".\n", symfile_objfile->name);

#ifdef FILES_INFO_HOOK
  if (FILES_INFO_HOOK ())
    return;
#endif

  for (item = target_stack; item; item = item->next)
    {
      t = item->target_ops;

      if (!t->to_has_memory)
	continue;

      if ((int)(t->to_stratum) <= (int)dummy_stratum)
	continue;
      if (has_all_mem)
	printf_unfiltered("\tWhile running this, GDB does not access memory from...\n");
      printf_unfiltered("%s:\n", t->to_longname);
      (t->to_files_info)(t);
      has_all_mem = t->to_has_all_memory;
    }
}

/* This is to be called by the open routine before it does
   anything.  */

void
target_preopen (from_tty)
     int from_tty;
{
  dont_repeat();

  if (target_has_execution)
    {   
      if (query ("A program is being debugged already.  Kill it? "))
        target_kill ();
      else
        error ("Program not killed.");
    }

  /* Calling target_kill may remove the target from the stack.  But if
     it doesn't (which seems like a win for UDI), remove it now.  */

  if (target_has_execution)
    pop_target ();
}

/* Detach a target after doing deferred register stores.  */

void
target_detach (args, from_tty)
     char *args;
     int from_tty;
{
  /* Handle any optimized stores to the inferior.  */
#ifdef DO_DEFERRED_STORES
  DO_DEFERRED_STORES;
#endif
  (current_target.to_detach) (args, from_tty);
}

void
target_link (modname, t_reloc)
     char *modname;
     CORE_ADDR *t_reloc;
{
  if (STREQ(current_target.to_shortname, "rombug"))
    {
      (current_target.to_lookup_symbol) (modname, t_reloc);
      if (*t_reloc == 0)
      error("Unable to link to %s and get relocation in rombug", modname);
    }
  else
    *t_reloc = (CORE_ADDR)-1;
}

/* Look through the list of possible targets for a target that can
   execute a run or attach command without any other data.  This is
   used to locate the default process stratum.

   Result is always valid (error() is called for errors).  */

static struct target_ops *
find_default_run_target (do_mesg)
     char *do_mesg;
{
  struct target_ops **t;
  struct target_ops *runable = NULL;
  int count;

  count = 0;

  for (t = target_structs; t < target_structs + target_struct_size;
       ++t)
    {
      if ((*t)->to_can_run && target_can_run(*t))
	{
	  runable = *t;
	  ++count;
	}
    }

  if (count != 1)
    error ("Don't know how to %s.  Try \"help target\".", do_mesg);

  return runable;
}

void
find_default_attach (args, from_tty)
     char *args;
     int from_tty;
{
  struct target_ops *t;

  t = find_default_run_target("attach");
  (t->to_attach) (args, from_tty);
  return;
}

void
find_default_require_attach (args, from_tty)
     char *args;
     int from_tty;
{
  struct target_ops *t;

  t = find_default_run_target("require_attach");
  (t->to_require_attach) (args, from_tty);
  return;
}

void
find_default_require_detach (pid, args, from_tty)
  int  pid;
  char *  args;
  int  from_tty;
{
  struct target_ops *t;

  t = find_default_run_target("require_detach");
  (t->to_require_detach) (pid, args, from_tty);
  return;
}

void
find_default_create_inferior (exec_file, allargs, env)
     char *exec_file;
     char *allargs;
     char **env;
{
  struct target_ops *t;

  t = find_default_run_target("run");
  (t->to_create_inferior) (exec_file, allargs, env);
  return;
}

void
find_default_clone_and_follow_inferior (child_pid, followed_child)
  int  child_pid;
  int  *followed_child;
{
  struct target_ops *t;

  t = find_default_run_target("run");
  (t->to_clone_and_follow_inferior) (child_pid, followed_child);
  return;
}

static int
return_zero ()
{
  return 0;
}

static int
return_one ()
{
  return 1;
}

/* Find a single runnable target in the stack and return it.  If for
   some reason there is more than one, return NULL.  */

struct target_ops *
find_run_target ()
{
  struct target_ops **t;
  struct target_ops *runable = NULL;
  int count;
  
  count = 0;
  
  for (t = target_structs; t < target_structs + target_struct_size; ++t)
    {
      if ((*t)->to_can_run && target_can_run(*t))
	{
	  runable = *t;
	  ++count;
	}
    }
  
  return (count == 1 ? runable : NULL);
}

struct target_ops *
find_core_target ()
{
  struct target_ops **t;
  struct target_ops *runable = NULL;
  int count;
  
  count = 0;
  
  for (t = target_structs; t < target_structs + target_struct_size;
       ++t)
    {
      if ((*t)->to_stratum == core_stratum)
	{
	  runable = *t;
	  ++count;
	}
    }
  
  return(count == 1 ? runable : NULL);
}

/* The inferior process has died.  Long live the inferior!  */

void
generic_mourn_inferior ()
{
  extern int show_breakpoint_hit_counts;

  inferior_pid = 0;
  attach_flag = 0;
  breakpoint_init_inferior (inf_exited);
  registers_changed ();

#ifdef CLEAR_DEFERRED_STORES
  /* Delete any pending stores to the inferior... */
  CLEAR_DEFERRED_STORES;
#endif

  reopen_exec_file ();
  reinit_frame_cache ();

  /* It is confusing to the user for ignore counts to stick around
     from previous runs of the inferior.  So clear them.  */
  /* However, it is more confusing for the ignore counts to disappear when
     using hit counts.  So don't clear them if we're counting hits.  */
  if (!show_breakpoint_hit_counts)
    breakpoint_clear_ignore_counts ();
}

/* This table must match in order and size the signals in enum target_signal
   in target.h.  */
static struct {
  char *name;
  char *string;
  } signals [] =
{
  {"0", "Signal 0"},
  {"SIGHUP", "Hangup"},
  {"SIGINT", "Interrupt"},
  {"SIGQUIT", "Quit"},
  {"SIGILL", "Illegal instruction"},
  {"SIGTRAP", "Trace/breakpoint trap"},
  {"SIGABRT", "Aborted"},
  {"SIGEMT", "Emulation trap"},
  {"SIGFPE", "Arithmetic exception"},
  {"SIGKILL", "Killed"},
  {"SIGBUS", "Bus error"},
  {"SIGSEGV", "Segmentation fault"},
  {"SIGSYS", "Bad system call"},
  {"SIGPIPE", "Broken pipe"},
  {"SIGALRM", "Alarm clock"},
  {"SIGTERM", "Terminated"},
  {"SIGURG", "Urgent I/O condition"},
  {"SIGSTOP", "Stopped (signal)"},
  {"SIGTSTP", "Stopped (user)"},
  {"SIGCONT", "Continued"},
  {"SIGCHLD", "Child status changed"},
  {"SIGTTIN", "Stopped (tty input)"},
  {"SIGTTOU", "Stopped (tty output)"},
  {"SIGIO", "I/O possible"},
  {"SIGXCPU", "CPU time limit exceeded"},
  {"SIGXFSZ", "File size limit exceeded"},
  {"SIGVTALRM", "Virtual timer expired"},
  {"SIGPROF", "Profiling timer expired"},
  {"SIGWINCH", "Window size changed"},
  {"SIGLOST", "Resource lost"},
  {"SIGUSR1", "User defined signal 1"},
  {"SIGUSR2", "User defined signal 2"},
  {"SIGPWR", "Power fail/restart"},
  {"SIGPOLL", "Pollable event occurred"},
  {"SIGWIND", "SIGWIND"},
  {"SIGPHONE", "SIGPHONE"},
  {"SIGWAITING", "Process's LWPs are blocked"},
  {"SIGLWP", "Signal LWP"},
  {"SIGDANGER", "Swap space dangerously low"},
  {"SIGGRANT", "Monitor mode granted"},
  {"SIGRETRACT", "Need to relinquish monitor mode"},
  {"SIGMSG", "Monitor mode data available"},
  {"SIGSOUND", "Sound completed"},
  {"SIGSAK", "Secure attention"},
  {"SIGPRIO", "SIGPRIO"},
  {"SIG33", "Real-time event 33"},
  {"SIG34", "Real-time event 34"},
  {"SIG35", "Real-time event 35"},
  {"SIG36", "Real-time event 36"},
  {"SIG37", "Real-time event 37"},
  {"SIG38", "Real-time event 38"},
  {"SIG39", "Real-time event 39"},
  {"SIG40", "Real-time event 40"},
  {"SIG41", "Real-time event 41"},
  {"SIG42", "Real-time event 42"},
  {"SIG43", "Real-time event 43"},
  {"SIG44", "Real-time event 44"},
  {"SIG45", "Real-time event 45"},
  {"SIG46", "Real-time event 46"},
  {"SIG47", "Real-time event 47"},
  {"SIG48", "Real-time event 48"},
  {"SIG49", "Real-time event 49"},
  {"SIG50", "Real-time event 50"},
  {"SIG51", "Real-time event 51"},
  {"SIG52", "Real-time event 52"},
  {"SIG53", "Real-time event 53"},
  {"SIG54", "Real-time event 54"},
  {"SIG55", "Real-time event 55"},
  {"SIG56", "Real-time event 56"},
  {"SIG57", "Real-time event 57"},
  {"SIG58", "Real-time event 58"},
  {"SIG59", "Real-time event 59"},
  {"SIG60", "Real-time event 60"},
  {"SIG61", "Real-time event 61"},
  {"SIG62", "Real-time event 62"},
  {"SIG63", "Real-time event 63"},
  {"SIGCANCEL", "LWP internal signal"},

#if defined(MACH) || defined(__MACH__)
  /* Mach exceptions */
  {"EXC_BAD_ACCESS", "Could not access memory"},
  {"EXC_BAD_INSTRUCTION", "Illegal instruction/operand"},
  {"EXC_ARITHMETIC", "Arithmetic exception"},
  {"EXC_EMULATION", "Emulation instruction"},
  {"EXC_SOFTWARE", "Software generated exception"},
  {"EXC_BREAKPOINT", "Breakpoint"},
#endif
  {"SIGINFO", "Information request"},

  {NULL, "Unknown signal"},
  {NULL, "Internal error: printing TARGET_SIGNAL_DEFAULT"},

  /* Last entry, used to check whether the table is the right size.  */
  {NULL, "TARGET_SIGNAL_MAGIC"}
};

/* Return the string for a signal.  */
char *
target_signal_to_string (sig)
     enum target_signal sig;
{
  if ((sig >= TARGET_SIGNAL_FIRST) && (sig <= TARGET_SIGNAL_LAST))
    return signals[sig].string;
  else
    return signals[TARGET_SIGNAL_UNKNOWN].string;
}

/* Return the name for a signal.  */
char *
target_signal_to_name (sig)
     enum target_signal sig;
{
  if (sig == TARGET_SIGNAL_UNKNOWN)
    /* I think the code which prints this will always print it along with
       the string, so no need to be verbose.  */
    return "?";
  return signals[sig].name;
}

/* Given a name, return its signal.  */
enum target_signal
target_signal_from_name (name)
     char *name;
{
  enum target_signal sig;

  /* It's possible we also should allow "SIGCLD" as well as "SIGCHLD"
     for TARGET_SIGNAL_SIGCHLD.  SIGIOT, on the other hand, is more
     questionable; seems like by now people should call it SIGABRT
     instead.  */

  /* This ugly cast brought to you by the native VAX compiler.  */
  for (sig = TARGET_SIGNAL_HUP;
       signals[sig].name != NULL;
       sig = (enum target_signal)((int)sig + 1))
    if (STREQ (name, signals[sig].name))
      return sig;
  return TARGET_SIGNAL_UNKNOWN;
}

/* The following functions are to help certain targets deal
   with the signal/waitstatus stuff.  They could just as well be in
   a file called native-utils.c or unixwaitstatus-utils.c or whatever.  */

/* Convert host signal to our signals.  */
enum target_signal
target_signal_from_host (hostsig)
     int hostsig;
{
  /* A switch statement would make sense but would require special kludges
     to deal with the cases where more than one signal has the same number.  */

  if (hostsig == 0) return TARGET_SIGNAL_0;

#if defined (SIGHUP)
  if (hostsig == SIGHUP) return TARGET_SIGNAL_HUP;
#endif
#if defined (SIGINT)
  if (hostsig == SIGINT) return TARGET_SIGNAL_INT;
#endif
#if defined (SIGQUIT)
  if (hostsig == SIGQUIT) return TARGET_SIGNAL_QUIT;
#endif
#if defined (SIGILL)
  if (hostsig == SIGILL) return TARGET_SIGNAL_ILL;
#endif
#if defined (SIGTRAP)
  if (hostsig == SIGTRAP) return TARGET_SIGNAL_TRAP;
#endif
#if defined (SIGABRT)
  if (hostsig == SIGABRT) return TARGET_SIGNAL_ABRT;
#endif
#if defined (SIGEMT)
  if (hostsig == SIGEMT) return TARGET_SIGNAL_EMT;
#endif
#if defined (SIGFPE)
  if (hostsig == SIGFPE) return TARGET_SIGNAL_FPE;
#endif
#if defined (SIGKILL)
  if (hostsig == SIGKILL) return TARGET_SIGNAL_KILL;
#endif
#if defined (SIGBUS)
  if (hostsig == SIGBUS) return TARGET_SIGNAL_BUS;
#endif
#if defined (SIGSEGV)
  if (hostsig == SIGSEGV) return TARGET_SIGNAL_SEGV;
#endif
#if defined (SIGSYS)
  if (hostsig == SIGSYS) return TARGET_SIGNAL_SYS;
#endif
#if defined (SIGPIPE)
  if (hostsig == SIGPIPE) return TARGET_SIGNAL_PIPE;
#endif
#if defined (SIGALRM)
  if (hostsig == SIGALRM) return TARGET_SIGNAL_ALRM;
#endif
#if defined (SIGTERM)
  if (hostsig == SIGTERM) return TARGET_SIGNAL_TERM;
#endif
#if defined (SIGUSR1)
  if (hostsig == SIGUSR1) return TARGET_SIGNAL_USR1;
#endif
#if defined (SIGUSR2)
  if (hostsig == SIGUSR2) return TARGET_SIGNAL_USR2;
#endif
#if defined (SIGCLD)
  if (hostsig == SIGCLD) return TARGET_SIGNAL_CHLD;
#endif
#if defined (SIGCHLD)
  if (hostsig == SIGCHLD) return TARGET_SIGNAL_CHLD;
#endif
#if defined (SIGPWR)
  if (hostsig == SIGPWR) return TARGET_SIGNAL_PWR;
#endif
#if defined (SIGWINCH)
  if (hostsig == SIGWINCH) return TARGET_SIGNAL_WINCH;
#endif
#if defined (SIGURG)
  if (hostsig == SIGURG) return TARGET_SIGNAL_URG;
#endif
#if defined (SIGIO)
  if (hostsig == SIGIO) return TARGET_SIGNAL_IO;
#endif
#if defined (SIGPOLL)
  if (hostsig == SIGPOLL) return TARGET_SIGNAL_POLL;
#endif
#if defined (SIGSTOP)
  if (hostsig == SIGSTOP) return TARGET_SIGNAL_STOP;
#endif
#if defined (SIGTSTP)
  if (hostsig == SIGTSTP) return TARGET_SIGNAL_TSTP;
#endif
#if defined (SIGCONT)
  if (hostsig == SIGCONT) return TARGET_SIGNAL_CONT;
#endif
#if defined (SIGTTIN)
  if (hostsig == SIGTTIN) return TARGET_SIGNAL_TTIN;
#endif
#if defined (SIGTTOU)
  if (hostsig == SIGTTOU) return TARGET_SIGNAL_TTOU;
#endif
#if defined (SIGVTALRM)
  if (hostsig == SIGVTALRM) return TARGET_SIGNAL_VTALRM;
#endif
#if defined (SIGPROF)
  if (hostsig == SIGPROF) return TARGET_SIGNAL_PROF;
#endif
#if defined (SIGXCPU)
  if (hostsig == SIGXCPU) return TARGET_SIGNAL_XCPU;
#endif
#if defined (SIGXFSZ)
  if (hostsig == SIGXFSZ) return TARGET_SIGNAL_XFSZ;
#endif
#if defined (SIGWIND)
  if (hostsig == SIGWIND) return TARGET_SIGNAL_WIND;
#endif
#if defined (SIGPHONE)
  if (hostsig == SIGPHONE) return TARGET_SIGNAL_PHONE;
#endif
#if defined (SIGLOST)
  if (hostsig == SIGLOST) return TARGET_SIGNAL_LOST;
#endif
#if defined (SIGWAITING)
  if (hostsig == SIGWAITING) return TARGET_SIGNAL_WAITING;
#endif
#if defined (SIGCANCEL)
  if (hostsig == SIGCANCEL) return TARGET_SIGNAL_CANCEL;
#endif
#if defined (SIGLWP)
  if (hostsig == SIGLWP) return TARGET_SIGNAL_LWP;
#endif
#if defined (SIGDANGER)
  if (hostsig == SIGDANGER) return TARGET_SIGNAL_DANGER;
#endif
#if defined (SIGGRANT)
  if (hostsig == SIGGRANT) return TARGET_SIGNAL_GRANT;
#endif
#if defined (SIGRETRACT)
  if (hostsig == SIGRETRACT) return TARGET_SIGNAL_RETRACT;
#endif
#if defined (SIGMSG)
  if (hostsig == SIGMSG) return TARGET_SIGNAL_MSG;
#endif
#if defined (SIGSOUND)
  if (hostsig == SIGSOUND) return TARGET_SIGNAL_SOUND;
#endif
#if defined (SIGSAK)
  if (hostsig == SIGSAK) return TARGET_SIGNAL_SAK;
#endif
#if defined (SIGPRIO)
  if (hostsig == SIGPRIO) return TARGET_SIGNAL_PRIO;
#endif

  /* Mach exceptions.  Assumes that the values for EXC_ are positive! */
#if defined (EXC_BAD_ACCESS) && defined (_NSIG)
  if (hostsig == _NSIG + EXC_BAD_ACCESS) return TARGET_EXC_BAD_ACCESS;
#endif
#if defined (EXC_BAD_INSTRUCTION) && defined (_NSIG)
  if (hostsig == _NSIG + EXC_BAD_INSTRUCTION) return TARGET_EXC_BAD_INSTRUCTION;
#endif
#if defined (EXC_ARITHMETIC) && defined (_NSIG)
  if (hostsig == _NSIG + EXC_ARITHMETIC) return TARGET_EXC_ARITHMETIC;
#endif
#if defined (EXC_EMULATION) && defined (_NSIG)
  if (hostsig == _NSIG + EXC_EMULATION) return TARGET_EXC_EMULATION;
#endif
#if defined (EXC_SOFTWARE) && defined (_NSIG)
  if (hostsig == _NSIG + EXC_SOFTWARE) return TARGET_EXC_SOFTWARE;
#endif
#if defined (EXC_BREAKPOINT) && defined (_NSIG)
  if (hostsig == _NSIG + EXC_BREAKPOINT) return TARGET_EXC_BREAKPOINT;
#endif

#if defined (SIGINFO)
  if (hostsig == SIGINFO) return TARGET_SIGNAL_INFO;
#endif

#if defined (REALTIME_LO)
  if (hostsig >= REALTIME_LO && hostsig < REALTIME_HI)
    return (enum target_signal)
      (hostsig - 33 + (int) TARGET_SIGNAL_REALTIME_33);
#endif
  return TARGET_SIGNAL_UNKNOWN;
}

int
target_signal_to_host (oursig)
     enum target_signal oursig;
{
  switch (oursig)
    {
    case TARGET_SIGNAL_0: return 0;

#if defined (SIGHUP)
    case TARGET_SIGNAL_HUP: return SIGHUP;
#endif
#if defined (SIGINT)
    case TARGET_SIGNAL_INT: return SIGINT;
#endif
#if defined (SIGQUIT)
    case TARGET_SIGNAL_QUIT: return SIGQUIT;
#endif
#if defined (SIGILL)
    case TARGET_SIGNAL_ILL: return SIGILL;
#endif
#if defined (SIGTRAP)
    case TARGET_SIGNAL_TRAP: return SIGTRAP;
#endif
#if defined (SIGABRT)
    case TARGET_SIGNAL_ABRT: return SIGABRT;
#endif
#if defined (SIGEMT)
    case TARGET_SIGNAL_EMT: return SIGEMT;
#endif
#if defined (SIGFPE)
    case TARGET_SIGNAL_FPE: return SIGFPE;
#endif
#if defined (SIGKILL)
    case TARGET_SIGNAL_KILL: return SIGKILL;
#endif
#if defined (SIGBUS)
    case TARGET_SIGNAL_BUS: return SIGBUS;
#endif
#if defined (SIGSEGV)
    case TARGET_SIGNAL_SEGV: return SIGSEGV;
#endif
#if defined (SIGSYS)
    case TARGET_SIGNAL_SYS: return SIGSYS;
#endif
#if defined (SIGPIPE)
    case TARGET_SIGNAL_PIPE: return SIGPIPE;
#endif
#if defined (SIGALRM)
    case TARGET_SIGNAL_ALRM: return SIGALRM;
#endif
#if defined (SIGTERM)
    case TARGET_SIGNAL_TERM: return SIGTERM;
#endif
#if defined (SIGUSR1)
    case TARGET_SIGNAL_USR1: return SIGUSR1;
#endif
#if defined (SIGUSR2)
    case TARGET_SIGNAL_USR2: return SIGUSR2;
#endif
#if defined (SIGCHLD) || defined (SIGCLD)
    case TARGET_SIGNAL_CHLD: 
#if defined (SIGCHLD)
      return SIGCHLD;
#else
      return SIGCLD;
#endif
#endif /* SIGCLD or SIGCHLD */
#if defined (SIGPWR)
    case TARGET_SIGNAL_PWR: return SIGPWR;
#endif
#if defined (SIGWINCH)
    case TARGET_SIGNAL_WINCH: return SIGWINCH;
#endif
#if defined (SIGURG)
    case TARGET_SIGNAL_URG: return SIGURG;
#endif
#if defined (SIGIO)
    case TARGET_SIGNAL_IO: return SIGIO;
#endif
#if defined (SIGPOLL)
    case TARGET_SIGNAL_POLL: return SIGPOLL;
#endif
#if defined (SIGSTOP)
    case TARGET_SIGNAL_STOP: return SIGSTOP;
#endif
#if defined (SIGTSTP)
    case TARGET_SIGNAL_TSTP: return SIGTSTP;
#endif
#if defined (SIGCONT)
    case TARGET_SIGNAL_CONT: return SIGCONT;
#endif
#if defined (SIGTTIN)
    case TARGET_SIGNAL_TTIN: return SIGTTIN;
#endif
#if defined (SIGTTOU)
    case TARGET_SIGNAL_TTOU: return SIGTTOU;
#endif
#if defined (SIGVTALRM)
    case TARGET_SIGNAL_VTALRM: return SIGVTALRM;
#endif
#if defined (SIGPROF)
    case TARGET_SIGNAL_PROF: return SIGPROF;
#endif
#if defined (SIGXCPU)
    case TARGET_SIGNAL_XCPU: return SIGXCPU;
#endif
#if defined (SIGXFSZ)
    case TARGET_SIGNAL_XFSZ: return SIGXFSZ;
#endif
#if defined (SIGWIND)
    case TARGET_SIGNAL_WIND: return SIGWIND;
#endif
#if defined (SIGPHONE)
    case TARGET_SIGNAL_PHONE: return SIGPHONE;
#endif
#if defined (SIGLOST)
    case TARGET_SIGNAL_LOST: return SIGLOST;
#endif
#if defined (SIGWAITING)
    case TARGET_SIGNAL_WAITING: return SIGWAITING;
#endif
#if defined (SIGCANCEL)
    case TARGET_SIGNAL_CANCEL: return SIGCANCEL;
#endif
#if defined (SIGLWP)
    case TARGET_SIGNAL_LWP: return SIGLWP;
#endif
#if defined (SIGDANGER)
    case TARGET_SIGNAL_DANGER: return SIGDANGER;
#endif
#if defined (SIGGRANT)
    case TARGET_SIGNAL_GRANT: return SIGGRANT;
#endif
#if defined (SIGRETRACT)
    case TARGET_SIGNAL_RETRACT: return SIGRETRACT;
#endif
#if defined (SIGMSG)
    case TARGET_SIGNAL_MSG: return SIGMSG;
#endif
#if defined (SIGSOUND)
    case TARGET_SIGNAL_SOUND: return SIGSOUND;
#endif
#if defined (SIGSAK)
    case TARGET_SIGNAL_SAK: return SIGSAK;
#endif
#if defined (SIGPRIO)
    case TARGET_SIGNAL_PRIO: return SIGPRIO;
#endif

      /* Mach exceptions.  Assumes that the values for EXC_ are positive! */
#if defined (EXC_BAD_ACCESS) && defined (_NSIG)
    case TARGET_EXC_BAD_ACCESS: return _NSIG + EXC_BAD_ACCESS;
#endif
#if defined (EXC_BAD_INSTRUCTION) && defined (_NSIG)
    case TARGET_EXC_BAD_INSTRUCTION: return _NSIG + EXC_BAD_INSTRUCTION;
#endif
#if defined (EXC_ARITHMETIC) && defined (_NSIG)
    case TARGET_EXC_ARITHMETIC: return _NSIG + EXC_ARITHMETIC;
#endif
#if defined (EXC_EMULATION) && defined (_NSIG)
    case TARGET_EXC_EMULATION: return _NSIG + EXC_EMULATION;
#endif
#if defined (EXC_SOFTWARE) && defined (_NSIG)
    case TARGET_EXC_SOFTWARE: return _NSIG + EXC_SOFTWARE;
#endif
#if defined (EXC_BREAKPOINT) && defined (_NSIG)
    case TARGET_EXC_BREAKPOINT: return _NSIG + EXC_BREAKPOINT;
#endif

#if defined (SIGINFO)
    case TARGET_SIGNAL_INFO: return SIGINFO;
#endif

    default:
#if defined (REALTIME_LO)
      if (oursig >= TARGET_SIGNAL_REALTIME_33
	  && oursig <= TARGET_SIGNAL_REALTIME_63)
	{
	  int retsig =
	    (int)oursig - (int)TARGET_SIGNAL_REALTIME_33 + REALTIME_LO;
	  if (retsig < REALTIME_HI)
	    return retsig;
	}
#endif
      /* The user might be trying to do "signal SIGSAK" where this system
	 doesn't have SIGSAK.  */
      warning ("Signal %s does not exist on this system.\n",
	       target_signal_to_name (oursig));
      return 0;
    }
}

/* Helper function for child_wait and the Lynx derivatives of child_wait.
   HOSTSTATUS is the waitstatus from wait() or the equivalent; store our
   translation of that in OURSTATUS.  */
void
store_waitstatus (ourstatus, hoststatus)
     struct target_waitstatus *ourstatus;
     int hoststatus;
{
#ifdef CHILD_SPECIAL_WAITSTATUS
  /* CHILD_SPECIAL_WAITSTATUS should return nonzero and set *OURSTATUS
     if it wants to deal with hoststatus.  */
  if (CHILD_SPECIAL_WAITSTATUS (ourstatus, hoststatus))
    return;
#endif

  if (WIFEXITED (hoststatus))
    {
      ourstatus->kind = TARGET_WAITKIND_EXITED;
      ourstatus->value.integer = WEXITSTATUS (hoststatus);
    }
  else if (!WIFSTOPPED (hoststatus))
    {
      ourstatus->kind = TARGET_WAITKIND_SIGNALLED;
      ourstatus->value.sig = target_signal_from_host (WTERMSIG (hoststatus));
    }
  else
    {
      ourstatus->kind = TARGET_WAITKIND_STOPPED;
      ourstatus->value.sig = target_signal_from_host (WSTOPSIG (hoststatus));
    }
}

/* In some circumstances we allow a command to specify a numeric
   signal.  The idea is to keep these circumstances limited so that
   users (and scripts) develop portable habits.  For comparison,
   POSIX.2 `kill' requires that 1,2,3,6,9,14, and 15 work (and using a
   numeric signal at all is obscelescent.  We are slightly more
   lenient and allow 1-15 which should match host signal numbers on
   most systems.  Use of symbolic signal names is strongly encouraged.  */

enum target_signal
target_signal_from_command (num)
     int num;
{
  if (num >= 1 && num <= 15)
    return (enum target_signal)num;
  error ("Only signals 1-15 are valid as numeric signals.\n\
Use \"info signals\" for a list of symbolic signals.");
}

/* Returns zero to leave the inferior alone, one to interrupt it.  */
int (*target_activity_function) PARAMS ((void));
int target_activity_fd;

/* Convert a normal process ID to a string.  Returns the string in a static
   buffer.  */

char *
normal_pid_to_str (pid)
     int pid;
{
  static char buf[30];

  if (STREQ (current_target.to_shortname, "remote"))
    sprintf (buf, "thread %d\0", pid);
  else
    sprintf (buf, "process %d\0", pid);

  return buf;
}

/* Some targets (such as ttrace-based HPUX) don't allow us to request
   notification of inferior events such as fork and vork immediately
   after the inferior is created.  (This because of how gdb gets an
   inferior created via invoking a shell to do it.  In such a scenario,
   if the shell init file has commands in it, the shell will fork and
   exec for each of those commands, and we will see each such fork
   event.  Very bad.)
   
   This function is used by all targets that allow us to request
   notification of forks, etc at inferior creation time; e.g., in
   target_acknowledge_forked_child.
   */
static void
normal_target_post_startup_inferior (pid)
  int  pid;
{
  /* This space intentionally left blank. */
}

/* Set up the handful of non-empty slots needed by the dummy target
   vector.  */

static void
init_dummy_target ()
{
  dummy_target.to_shortname = "None";
  dummy_target.to_longname = "None";
  dummy_target.to_doc = "";
  dummy_target.to_attach = find_default_attach;
  dummy_target.to_require_attach = find_default_require_attach;
  dummy_target.to_require_detach = find_default_require_detach;
  dummy_target.to_create_inferior = find_default_create_inferior;
  dummy_target.to_clone_and_follow_inferior = find_default_clone_and_follow_inferior;
  dummy_target.to_stratum = dummy_stratum;
  dummy_target.to_magic = OPS_MAGIC;
}


static struct target_ops debug_target;

static void
debug_to_open (args, from_tty)
     char *args;
     int from_tty;
{
  debug_target.to_open (args, from_tty);

  fprintf_unfiltered (gdb_stderr, "target_open (%s, %d)\n", args, from_tty);
}

static void
debug_to_close (quitting)
     int quitting;
{
  debug_target.to_close (quitting);

  fprintf_unfiltered (gdb_stderr, "target_close (%d)\n", quitting);
}

static void
debug_to_attach (args, from_tty)
     char *args;
     int from_tty;
{
  debug_target.to_attach (args, from_tty);

  fprintf_unfiltered (gdb_stderr, "target_attach (%s, %d)\n", args, from_tty);
}


static void
debug_to_post_attach (pid)
  int  pid;
{
  debug_target.to_post_attach (pid);

  fprintf_unfiltered (gdb_stderr, "target_post_attach (%d)\n", pid);
}

static void
debug_to_require_attach (args, from_tty)
     char *args;
     int from_tty;
{
  debug_target.to_require_attach (args, from_tty);

  fprintf_unfiltered (gdb_stderr,
		      "target_require_attach (%s, %d)\n", args, from_tty);
}

static void
debug_to_detach (args, from_tty)
     char *args;
     int from_tty;
{
  debug_target.to_detach (args, from_tty);

  fprintf_unfiltered (gdb_stderr, "target_detach (%s, %d)\n", args, from_tty);
}

static void
debug_to_require_detach (pid, args, from_tty)
  int  pid;
  char *  args;
  int  from_tty;
{
  debug_target.to_require_detach (pid, args, from_tty);

  fprintf_unfiltered (gdb_stderr,
		      "target_require_detach (%d, %s, %d)\n", pid, args, from_tty);
}

static void
debug_to_resume (pid, step, siggnal)
     int pid;
     int step;
     enum target_signal siggnal;
{
  debug_target.to_resume (pid, step, siggnal);

  fprintf_unfiltered (gdb_stderr, "target_resume (%d, %s, %s)\n", pid,
		      step ? "step" : "continue",
		      target_signal_to_name (siggnal));
}

static int
debug_to_wait (pid, status)
     int pid;
     struct target_waitstatus *status;
{
  int retval;

  retval = debug_target.to_wait (pid, status);

  fprintf_unfiltered (gdb_stderr,
		      "target_wait (%d, status) = %d,   ", pid, retval);
  fprintf_unfiltered (gdb_stderr, "status->kind = ");
  switch (status->kind)
    {
    case TARGET_WAITKIND_EXITED:
      fprintf_unfiltered (gdb_stderr, "exited, status = %d\n",
			  status->value.integer);
      break;
    case TARGET_WAITKIND_STOPPED:
      fprintf_unfiltered (gdb_stderr, "stopped, signal = %s\n",
			  target_signal_to_name (status->value.sig));
      break;
    case TARGET_WAITKIND_SIGNALLED:
      fprintf_unfiltered (gdb_stderr, "signalled, signal = %s\n",
			  target_signal_to_name (status->value.sig));
      break;
    case TARGET_WAITKIND_LOADED:
      fprintf_unfiltered (gdb_stderr, "loaded\n");
      break;
    case TARGET_WAITKIND_FORKED:
      fprintf_unfiltered (gdb_stderr, "forked\n");
      break;
    case TARGET_WAITKIND_VFORKED:
      fprintf_unfiltered (gdb_stderr, "vforked\n");
      break;
    case TARGET_WAITKIND_EXECD:
      fprintf_unfiltered (gdb_stderr, "execd\n");
      break;
    case TARGET_WAITKIND_SPURIOUS:
      fprintf_unfiltered (gdb_stderr, "spurious\n");
      break;
    default:
      fprintf_unfiltered (gdb_stderr, "unknown???\n");
      break;
    }

  return retval;
}

static void
debug_to_post_wait (pid, status)
  int  pid;
  int  status;
{
  debug_target.to_post_wait (pid, status);

  fprintf_unfiltered (gdb_stderr, "target_post_wait (%d, %d)\n",
		      pid, status);
}

static void
debug_to_fetch_registers (regno)
     int regno;
{
  debug_target.to_fetch_registers (regno);

  fprintf_unfiltered (gdb_stderr, "target_fetch_registers (%s)",
		      regno != -1 ? REGISTER_NAME (regno) : "-1");
  if (regno != -1)
    fprintf_unfiltered (gdb_stderr, " = 0x%x %d",
			(unsigned long) read_register (regno),
			read_register (regno));
  fprintf_unfiltered (gdb_stderr, "\n");
}

static void
debug_to_store_registers (regno)
     int regno;
{
  debug_target.to_store_registers (regno);

  if (regno >= 0 && regno < NUM_REGS)
    fprintf_unfiltered (gdb_stderr, "target_store_registers (%s) = 0x%x %d\n",
			REGISTER_NAME (regno),
			(unsigned long) read_register (regno),
			(unsigned long) read_register (regno));
  else
    fprintf_unfiltered (gdb_stderr, "target_store_registers (%d)\n", regno);
}

static void
debug_to_prepare_to_store ()
{
  debug_target.to_prepare_to_store ();

  fprintf_unfiltered (gdb_stderr, "target_prepare_to_store ()\n");
}

static int
debug_to_xfer_memory (memaddr, myaddr, len, write, target)
     CORE_ADDR memaddr;
     char *myaddr;
     int len;
     int write;
     struct target_ops *target;
{
  int retval;

  retval = debug_target.to_xfer_memory (memaddr, myaddr, len, write, target);

  fprintf_unfiltered (gdb_stderr,
		      "target_xfer_memory (0x%x, xxx, %d, %s, xxx) = %d",
		      (unsigned int) memaddr, /* possable truncate long long */
		      len, write ? "write" : "read", retval);

  

  if (retval > 0)
    {
      int i;

      fputs_unfiltered (", bytes =", gdb_stderr);
      for (i = 0; i < retval; i++)
	{
	  if ((((long) &(myaddr[i])) & 0xf) == 0)
	    fprintf_unfiltered (gdb_stderr, "\n");
	  fprintf_unfiltered (gdb_stderr, " %02x", myaddr[i] & 0xff);
	}
    }

  fputc_unfiltered ('\n', gdb_stderr);

  return retval;
}

static void
debug_to_files_info (target)
     struct target_ops *target;
{
  debug_target.to_files_info (target);

  fprintf_unfiltered (gdb_stderr, "target_files_info (xxx)\n");
}

static int
debug_to_insert_breakpoint (addr, save)
     CORE_ADDR addr;
     char *save;
{
  int retval;

  retval = debug_target.to_insert_breakpoint (addr, save);

  fprintf_unfiltered (gdb_stderr,
		      "target_insert_breakpoint (0x%x, xxx) = %d\n",
		      (unsigned long) addr, retval);
  return retval;
}

static int
debug_to_remove_breakpoint (addr, save)
     CORE_ADDR addr;
     char *save;
{
  int retval;

  retval = debug_target.to_remove_breakpoint (addr, save);

  fprintf_unfiltered (gdb_stderr,
		      "target_remove_breakpoint (0x%x, xxx) = %d\n",
		      (unsigned long)addr, retval);
  return retval;
}

static void
debug_to_terminal_init ()
{
  debug_target.to_terminal_init ();

  fprintf_unfiltered (gdb_stderr, "target_terminal_init ()\n");
}

static void
debug_to_terminal_inferior ()
{
  debug_target.to_terminal_inferior ();

  fprintf_unfiltered (gdb_stderr, "target_terminal_inferior ()\n");
}

static void
debug_to_terminal_ours_for_output ()
{
  debug_target.to_terminal_ours_for_output ();

  fprintf_unfiltered (gdb_stderr, "target_terminal_ours_for_output ()\n");
}

static void
debug_to_terminal_ours ()
{
  debug_target.to_terminal_ours ();

  fprintf_unfiltered (gdb_stderr, "target_terminal_ours ()\n");
}

static void
debug_to_terminal_info (arg, from_tty)
     char *arg;
     int from_tty;
{
  debug_target.to_terminal_info (arg, from_tty);

  fprintf_unfiltered (gdb_stderr, "target_terminal_info (%s, %d)\n", arg,
		      from_tty);
}

static void
debug_to_kill ()
{
  debug_target.to_kill ();

  fprintf_unfiltered (gdb_stderr, "target_kill ()\n");
}

static void
debug_to_load (args, from_tty)
     char *args;
     int from_tty;
{
  debug_target.to_load (args, from_tty);

  fprintf_unfiltered (gdb_stderr, "target_load (%s, %d)\n", args, from_tty);
}

static int
debug_to_lookup_symbol (name, addrp)
     char *name;
     CORE_ADDR *addrp;
{
  int retval;

  retval = debug_target.to_lookup_symbol (name, addrp);

  fprintf_unfiltered (gdb_stderr, "target_lookup_symbol (%s, xxx)\n", name);

  return retval;
}

static void
debug_to_create_inferior (exec_file, args, env)
     char *exec_file;
     char *args;
     char **env;
{
  debug_target.to_create_inferior (exec_file, args, env);

  fprintf_unfiltered (gdb_stderr, "target_create_inferior (%s, %s, xxx)\n",
		      exec_file, args);
}

static void
debug_to_post_startup_inferior (pid)
  int  pid;
{
  debug_target.to_post_startup_inferior (pid);

  fprintf_unfiltered (gdb_stderr, "target_post_startup_inferior (%d)\n",
		      pid);
}

static void
debug_to_acknowledge_created_inferior (pid)
  int  pid;
{
  debug_target.to_acknowledge_created_inferior (pid);

  fprintf_unfiltered (gdb_stderr, "target_acknowledge_created_inferior (%d)\n",
		      pid);
}

static void
debug_to_clone_and_follow_inferior (child_pid, followed_child)
  int  child_pid;
  int  *followed_child;
{
  debug_target.to_clone_and_follow_inferior (child_pid, followed_child);

  fprintf_unfiltered (gdb_stderr,
		      "target_clone_and_follow_inferior (%d, %d)\n",
		      child_pid, *followed_child);
}

static void
debug_to_post_follow_inferior_by_clone ()
{
  debug_target.to_post_follow_inferior_by_clone ();

  fprintf_unfiltered (gdb_stderr, "target_post_follow_inferior_by_clone ()\n");
}

static int
debug_to_insert_fork_catchpoint (pid)
  int  pid;
{
  int  retval;

  retval = debug_target.to_insert_fork_catchpoint (pid);

  fprintf_unfiltered (gdb_stderr, "target_insert_fork_catchpoint (%d) = %d\n",
                      pid, retval);

  return retval;
}

static int
debug_to_remove_fork_catchpoint (pid)
  int  pid;
{
  int  retval;

  retval = debug_target.to_remove_fork_catchpoint (pid);

  fprintf_unfiltered (gdb_stderr, "target_remove_fork_catchpoint (%d) = %d\n",
                      pid, retval);

  return retval;
}

static int
debug_to_insert_vfork_catchpoint (pid)
  int  pid;
{
  int  retval;

  retval = debug_target.to_insert_vfork_catchpoint (pid);

  fprintf_unfiltered (gdb_stderr, "target_insert_vfork_catchpoint (%d)= %d\n",
                      pid, retval);

  return retval;
}

static int
debug_to_remove_vfork_catchpoint (pid)
  int  pid;
{
  int  retval;

  retval = debug_target.to_remove_vfork_catchpoint (pid);

  fprintf_unfiltered (gdb_stderr, "target_remove_vfork_catchpoint (%d) = %d\n",
                      pid, retval);

  return retval;
}

static int
debug_to_has_forked (pid, child_pid)
  int  pid;
  int *  child_pid;
{
  int  has_forked;

  has_forked = debug_target.to_has_forked (pid, child_pid);

  fprintf_unfiltered (gdb_stderr, "target_has_forked (%d, %d) = %d\n",
                      pid, *child_pid, has_forked);

  return has_forked;
}

static int
debug_to_has_vforked (pid, child_pid)
  int  pid;
  int *  child_pid;
{
  int  has_vforked;

  has_vforked = debug_target.to_has_vforked (pid, child_pid);

  fprintf_unfiltered (gdb_stderr, "target_has_vforked (%d, %d) = %d\n",
                      pid, *child_pid, has_vforked);

  return has_vforked;
}

static int
debug_to_can_follow_vfork_prior_to_exec ()
{
  int  can_immediately_follow_vfork;

  can_immediately_follow_vfork = debug_target.to_can_follow_vfork_prior_to_exec ();

  fprintf_unfiltered (gdb_stderr, "target_can_follow_vfork_prior_to_exec () = %d\n",
                      can_immediately_follow_vfork);

  return can_immediately_follow_vfork;
}

static void
debug_to_post_follow_vfork (parent_pid, followed_parent, child_pid, followed_child)
  int  parent_pid;
  int  followed_parent;
  int  child_pid;
  int  followed_child;
{
  debug_target.to_post_follow_vfork (parent_pid, followed_parent, child_pid, followed_child);

  fprintf_unfiltered (gdb_stderr,
		      "target_post_follow_vfork (%d, %d, %d, %d)\n",
                      parent_pid, followed_parent, child_pid, followed_child);
}

static int
debug_to_insert_exec_catchpoint (pid)
  int  pid;
{
  int  retval;

  retval = debug_target.to_insert_exec_catchpoint (pid);

  fprintf_unfiltered (gdb_stderr, "target_insert_exec_catchpoint (%d) = %d\n",
                      pid, retval);

  return retval;
}

static int
debug_to_remove_exec_catchpoint (pid)
  int  pid;
{
  int  retval;

  retval = debug_target.to_remove_exec_catchpoint (pid);

  fprintf_unfiltered (gdb_stderr, "target_remove_exec_catchpoint (%d) = %d\n",
                      pid, retval);

  return retval;
}

static int
debug_to_has_execd (pid, execd_pathname)
  int  pid;
  char **  execd_pathname;
{
  int  has_execd;

  has_execd = debug_target.to_has_execd (pid, execd_pathname);

  fprintf_unfiltered (gdb_stderr, "target_has_execd (%d, %s) = %d\n",
                      pid, (*execd_pathname ? *execd_pathname : "<NULL>"),
		      has_execd);

  return has_execd;
}

static int
debug_to_reported_exec_events_per_exec_call ()
{
  int  reported_exec_events;

  reported_exec_events = debug_target.to_reported_exec_events_per_exec_call ();

  fprintf_unfiltered (gdb_stderr,
		      "target_reported_exec_events_per_exec_call () = %d\n",
                      reported_exec_events);

  return reported_exec_events;
}

static int
debug_to_has_syscall_event (pid, kind, syscall_id)
  int  pid;
  enum target_waitkind *  kind;
  int *  syscall_id;
{
  int  has_syscall_event;
  char *  kind_spelling = "??";

  has_syscall_event = debug_target.to_has_syscall_event (pid, kind, syscall_id);
  if (has_syscall_event)
    {
      switch (*kind)
        {
          case TARGET_WAITKIND_SYSCALL_ENTRY:
            kind_spelling = "SYSCALL_ENTRY";
            break;
          case TARGET_WAITKIND_SYSCALL_RETURN:
            kind_spelling = "SYSCALL_RETURN";
            break;
          default:
            break;
        }
    }

  fprintf_unfiltered (gdb_stderr,
		      "target_has_syscall_event (%d, %s, %d) = %d\n",
                      pid, kind_spelling, *syscall_id, has_syscall_event);

  return has_syscall_event;
}

static int
debug_to_has_exited (pid, wait_status, exit_status)
  int  pid;
  int  wait_status;
  int *  exit_status;
{
  int  has_exited;

  has_exited = debug_target.to_has_exited (pid, wait_status, exit_status);

  fprintf_unfiltered (gdb_stderr, "target_has_exited (%d, %d, %d) = %d\n",
                      pid, wait_status, *exit_status, has_exited);

  return has_exited;
}

static void
debug_to_mourn_inferior ()
{
  debug_target.to_mourn_inferior ();

  fprintf_unfiltered (gdb_stderr, "target_mourn_inferior ()\n");
}

static int
debug_to_can_run ()
{
  int retval;

  retval = debug_target.to_can_run ();

  fprintf_unfiltered (gdb_stderr, "target_can_run () = %d\n", retval);

  return retval;
}

static void
debug_to_notice_signals (pid)
     int pid;
{
  debug_target.to_notice_signals (pid);

  fprintf_unfiltered (gdb_stderr, "target_notice_signals (%d)\n", pid);
}

static int
debug_to_thread_alive (pid)
     int pid;
{
  int retval;

  retval = debug_target.to_thread_alive (pid);

  fprintf_unfiltered (gdb_stderr, "target_thread_alive (%d) = %d\n",
		      pid, retval);

  return retval;
}

static void
debug_to_stop ()
{
  debug_target.to_stop ();

  fprintf_unfiltered (gdb_stderr, "target_stop ()\n");
}

static int
debug_to_query (type, req, resp, siz)
  int type;
  char *req;
  char *resp;
  int *siz;
{
  int retval;

  retval = debug_target.to_query (type, req, resp, siz);

  fprintf_unfiltered (gdb_stderr, "target_query (%c, %s, %s,  %d) = %d\n", type, req, resp, *siz, retval);

  return retval;
}

static struct symtab_and_line *
debug_to_enable_exception_callback (kind, enable)
  enum exception_event_kind kind;
  int enable;
{
  struct symtab_and_line *result;
  result = debug_target.to_enable_exception_callback (kind, enable);
  fprintf_unfiltered (gdb_stderr,
		      "target get_exception_callback_sal (%d, %d)\n",
		      kind, enable);
  return result;
}

static struct exception_event_record *
debug_to_get_current_exception_event ()
{
  struct exception_event_record *result;
  result = debug_target.to_get_current_exception_event();
  fprintf_unfiltered (gdb_stderr, "target get_current_exception_event ()\n");
  return result;
}

static char *
debug_to_pid_to_exec_file (pid)
  int  pid;
{
  char *  exec_file;

  exec_file = debug_target.to_pid_to_exec_file (pid);

  fprintf_unfiltered (gdb_stderr, "target_pid_to_exec_file (%d) = %s\n",
                      pid, exec_file);

  return exec_file;
}

static char *
debug_to_core_file_to_sym_file (core)
  char *  core;
{
  char *  sym_file;

  sym_file = debug_target.to_core_file_to_sym_file (core);

  fprintf_unfiltered (gdb_stderr, "target_core_file_to_sym_file (%s) = %s\n",
                      core, sym_file);

  return sym_file;
}

static void
setup_target_debug ()
{
  memcpy (&debug_target, &current_target, sizeof debug_target);

  current_target.to_open = debug_to_open;
  current_target.to_close = debug_to_close;
  current_target.to_attach = debug_to_attach;
  current_target.to_post_attach = debug_to_post_attach;
  current_target.to_require_attach = debug_to_require_attach;
  current_target.to_detach = debug_to_detach;
  current_target.to_require_detach = debug_to_require_detach;
  current_target.to_resume = debug_to_resume;
  current_target.to_wait = debug_to_wait;
  current_target.to_post_wait = debug_to_post_wait;
  current_target.to_fetch_registers = debug_to_fetch_registers;
  current_target.to_store_registers = debug_to_store_registers;
  current_target.to_prepare_to_store = debug_to_prepare_to_store;
  current_target.to_xfer_memory = debug_to_xfer_memory;
  current_target.to_files_info = debug_to_files_info;
  current_target.to_insert_breakpoint = debug_to_insert_breakpoint;
  current_target.to_remove_breakpoint = debug_to_remove_breakpoint;
  current_target.to_terminal_init = debug_to_terminal_init;
  current_target.to_terminal_inferior = debug_to_terminal_inferior;
  current_target.to_terminal_ours_for_output = debug_to_terminal_ours_for_output;
  current_target.to_terminal_ours = debug_to_terminal_ours;
  current_target.to_terminal_info = debug_to_terminal_info;
  current_target.to_kill = debug_to_kill;
  current_target.to_load = debug_to_load;
  current_target.to_lookup_symbol = debug_to_lookup_symbol;
  current_target.to_create_inferior = debug_to_create_inferior;
  current_target.to_post_startup_inferior = debug_to_post_startup_inferior;
  current_target.to_acknowledge_created_inferior = debug_to_acknowledge_created_inferior;
  current_target.to_clone_and_follow_inferior = debug_to_clone_and_follow_inferior;
  current_target.to_post_follow_inferior_by_clone = debug_to_post_follow_inferior_by_clone;
  current_target.to_insert_fork_catchpoint = debug_to_insert_fork_catchpoint;
  current_target.to_remove_fork_catchpoint = debug_to_remove_fork_catchpoint;
  current_target.to_insert_vfork_catchpoint = debug_to_insert_vfork_catchpoint;
  current_target.to_remove_vfork_catchpoint = debug_to_remove_vfork_catchpoint;
  current_target.to_has_forked = debug_to_has_forked;
  current_target.to_has_vforked = debug_to_has_vforked;
  current_target.to_can_follow_vfork_prior_to_exec = debug_to_can_follow_vfork_prior_to_exec;
  current_target.to_post_follow_vfork = debug_to_post_follow_vfork;
  current_target.to_insert_exec_catchpoint = debug_to_insert_exec_catchpoint;
  current_target.to_remove_exec_catchpoint = debug_to_remove_exec_catchpoint;
  current_target.to_has_execd = debug_to_has_execd;
  current_target.to_reported_exec_events_per_exec_call = debug_to_reported_exec_events_per_exec_call;
  current_target.to_has_syscall_event = debug_to_has_syscall_event;
  current_target.to_has_exited = debug_to_has_exited;
  current_target.to_mourn_inferior = debug_to_mourn_inferior;
  current_target.to_can_run = debug_to_can_run;
  current_target.to_notice_signals = debug_to_notice_signals;
  current_target.to_thread_alive = debug_to_thread_alive;
  current_target.to_stop = debug_to_stop;
  current_target.to_query = debug_to_query;
  current_target.to_enable_exception_callback = debug_to_enable_exception_callback;
  current_target.to_get_current_exception_event = debug_to_get_current_exception_event;
  current_target.to_pid_to_exec_file = debug_to_pid_to_exec_file;
  current_target.to_core_file_to_sym_file = debug_to_core_file_to_sym_file;

}


static char targ_desc[] = 
    "Names of targets and files being debugged.\n\
Shows the entire stack of targets currently in use (including the exec-file,\n\
core-file, and process, if any), as well as the symbol file name.";

void
initialize_targets ()
{
  init_dummy_target ();
  push_target (&dummy_target);

  add_info ("target", target_info, targ_desc);
  add_info ("files", target_info, targ_desc);

  add_show_from_set (
     add_set_cmd ("targetdebug", class_maintenance, var_zinteger,
		  (char *)&targetdebug,
		 "Set target debugging.\n\
When non-zero, target debugging is enabled.", &setlist),
		     &showlist);

  if (!STREQ (signals[TARGET_SIGNAL_LAST].string, "TARGET_SIGNAL_MAGIC"))
    abort ();
}