aboutsummaryrefslogtreecommitdiff
path: root/gdb/infcmd.c
blob: 0680caa05ea81109e2381074d2ed4eab0b4597fb (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
/* Memory-access and commands for "inferior" process, for GDB.
   Copyright 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995,
   1996, 1997, 1998, 1999, 2000, 2001, 2002
   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 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 <signal.h>
#include "gdb_string.h"
#include "symtab.h"
#include "gdbtypes.h"
#include "frame.h"
#include "inferior.h"
#include "environ.h"
#include "value.h"
#include "gdbcmd.h"
#include "symfile.h"
#include "gdbcore.h"
#include "target.h"
#include "language.h"
#include "symfile.h"
#include "objfiles.h"
#include "completer.h"
#include "ui-out.h"
#include "event-top.h"
#include "parser-defs.h"

/* Functions exported for general use: */

void nofp_registers_info (char *, int);

void all_registers_info (char *, int);

void registers_info (char *, int);

/* Local functions: */

void continue_command (char *, int);

static void print_return_value (int struct_return, struct type *value_type);

static void finish_command_continuation (struct continuation_arg *);

static void until_next_command (int);

static void until_command (char *, int);

static void path_info (char *, int);

static void path_command (char *, int);

static void unset_command (char *, int);

static void float_info (char *, int);

static void detach_command (char *, int);

static void interrupt_target_command (char *args, int from_tty);

static void unset_environment_command (char *, int);

static void set_environment_command (char *, int);

static void environment_info (char *, int);

static void program_info (char *, int);

static void finish_command (char *, int);

static void signal_command (char *, int);

static void jump_command (char *, int);

static void step_1 (int, int, char *);
static void step_once (int skip_subroutines, int single_inst, int count);
static void step_1_continuation (struct continuation_arg *arg);

void nexti_command (char *, int);

void stepi_command (char *, int);

static void next_command (char *, int);

static void step_command (char *, int);

static void run_command (char *, int);

static void run_no_args_command (char *args, int from_tty);

static void go_command (char *line_no, int from_tty);

static int strip_bg_char (char **);

void _initialize_infcmd (void);

#define GO_USAGE   "Usage: go <location>\n"

static void breakpoint_auto_delete_contents (PTR);

#define ERROR_NO_INFERIOR \
   if (!target_has_execution) error ("The program is not being run.");

/* String containing arguments to give to the program, separated by spaces.
   Empty string (pointer to '\0') means no args.  */

static char *inferior_args;

/* The inferior arguments as a vector.  If INFERIOR_ARGC is nonzero,
   then we must compute INFERIOR_ARGS from this (via the target).  */

static int inferior_argc;
static char **inferior_argv;

/* File name for default use for standard in/out in the inferior.  */

char *inferior_io_terminal;

/* Pid of our debugged inferior, or 0 if no inferior now.
   Since various parts of infrun.c test this to see whether there is a program
   being debugged it should be nonzero (currently 3 is used) for remote
   debugging.  */

ptid_t inferior_ptid;

/* Last signal that the inferior received (why it stopped).  */

enum target_signal stop_signal;

/* Address at which inferior stopped.  */

CORE_ADDR stop_pc;

/* Chain containing status of breakpoint(s) that we have stopped at.  */

bpstat stop_bpstat;

/* Flag indicating that a command has proceeded the inferior past the
   current breakpoint.  */

int breakpoint_proceeded;

/* Nonzero if stopped due to a step command.  */

int stop_step;

/* Nonzero if stopped due to completion of a stack dummy routine.  */

int stop_stack_dummy;

/* Nonzero if stopped due to a random (unexpected) signal in inferior
   process.  */

int stopped_by_random_signal;

/* Range to single step within.
   If this is nonzero, respond to a single-step signal
   by continuing to step if the pc is in this range.  */

CORE_ADDR step_range_start;	/* Inclusive */
CORE_ADDR step_range_end;	/* Exclusive */

/* Stack frame address as of when stepping command was issued.
   This is how we know when we step into a subroutine call,
   and how to set the frame for the breakpoint used to step out.  */

CORE_ADDR step_frame_address;

/* Our notion of the current stack pointer.  */

CORE_ADDR step_sp;

enum step_over_calls_kind step_over_calls;

/* If stepping, nonzero means step count is > 1
   so don't print frame next time inferior stops
   if it stops due to stepping.  */

int step_multi;

/* Environment to use for running inferior,
   in format described in environ.h.  */

struct environ *inferior_environ;

/* Accessor routines. */

char *
get_inferior_args (void)
{
  if (inferior_argc != 0)
    {
      char *n, *old;

      n = gdbarch_construct_inferior_arguments (current_gdbarch,
						inferior_argc, inferior_argv);
      old = set_inferior_args (n);
      xfree (old);
    }

  if (inferior_args == NULL)
    inferior_args = xstrdup ("");

  return inferior_args;
}

char *
set_inferior_args (char *newargs)
{
  char *saved_args = inferior_args;

  inferior_args = newargs;
  inferior_argc = 0;
  inferior_argv = 0;

  return saved_args;
}

void
set_inferior_args_vector (int argc, char **argv)
{
  inferior_argc = argc;
  inferior_argv = argv;
}

/* Notice when `set args' is run.  */
static void
notice_args_set (char *args, int from_tty, struct cmd_list_element *c)
{
  inferior_argc = 0;
  inferior_argv = 0;
}

/* Notice when `show args' is run.  */
static void
notice_args_read (char *args, int from_tty, struct cmd_list_element *c)
{
  /* Might compute the value.  */
  get_inferior_args ();
}


/* Compute command-line string given argument vector.  This does the
   same shell processing as fork_inferior.  */
/* ARGSUSED */
char *
construct_inferior_arguments (struct gdbarch *gdbarch, int argc, char **argv)
{
  char *result;

  if (STARTUP_WITH_SHELL)
    {
      /* This holds all the characters considered special to the
	 typical Unix shells.  We include `^' because the SunOS
	 /bin/sh treats it as a synonym for `|'.  */
      char *special = "\"!#$&*()\\|[]{}<>?'\"`~^; \t\n";
      int i;
      int length = 0;
      char *out, *cp;

      /* We over-compute the size.  It shouldn't matter.  */
      for (i = 0; i < argc; ++i)
	length += 2 * strlen (argv[i]) + 1;

      result = (char *) xmalloc (length);
      out = result;

      for (i = 0; i < argc; ++i)
	{
	  if (i > 0)
	    *out++ = ' ';

	  for (cp = argv[i]; *cp; ++cp)
	    {
	      if (strchr (special, *cp) != NULL)
		*out++ = '\\';
	      *out++ = *cp;
	    }
	}
      *out = '\0';
    }
  else
    {
      /* In this case we can't handle arguments that contain spaces,
	 tabs, or newlines -- see breakup_args().  */
      int i;
      int length = 0;

      for (i = 0; i < argc; ++i)
	{
	  char *cp = strchr (argv[i], ' ');
	  if (cp == NULL)
	    cp = strchr (argv[i], '\t');
	  if (cp == NULL)
	    cp = strchr (argv[i], '\n');
	  if (cp != NULL)
	    error ("can't handle command-line argument containing whitespace");
	  length += strlen (argv[i]) + 1;
	}

      result = (char *) xmalloc (length);
      result[0] = '\0';
      for (i = 0; i < argc; ++i)
	{
	  if (i > 0)
	    strcat (result, " ");
	  strcat (result, argv[i]);
	}
    }

  return result;
}


/* This function detects whether or not a '&' character (indicating
   background execution) has been added as *the last* of the arguments ARGS
   of a command. If it has, it removes it and returns 1. Otherwise it
   does nothing and returns 0. */
static int
strip_bg_char (char **args)
{
  char *p = NULL;

  p = strchr (*args, '&');

  if (p)
    {
      if (p == (*args + strlen (*args) - 1))
	{
	  if (strlen (*args) > 1)
	    {
	      do
		p--;
	      while (*p == ' ' || *p == '\t');
	      *(p + 1) = '\0';
	    }
	  else
	    *args = 0;
	  return 1;
	}
    }
  return 0;
}

/* ARGSUSED */
void
tty_command (char *file, int from_tty)
{
  if (file == 0)
    error_no_arg ("terminal name for running target process");

  inferior_io_terminal = savestring (file, strlen (file));
}

static void
run_command (char *args, int from_tty)
{
  char *exec_file;

  dont_repeat ();

  if (! ptid_equal (inferior_ptid, null_ptid) && target_has_execution)
    {
      if (from_tty
	  && !query ("The program being debugged has been started already.\n\
Start it from the beginning? "))
	error ("Program not restarted.");
      target_kill ();
#if defined(SOLIB_RESTART)
      SOLIB_RESTART ();
#endif
      init_wait_for_inferior ();
    }

  clear_breakpoint_hit_counts ();

  /* Purge old solib objfiles. */
  objfile_purge_solibs ();

  do_run_cleanups (NULL);

  /* The comment here used to read, "The exec file is re-read every
     time we do a generic_mourn_inferior, so we just have to worry
     about the symbol file."  The `generic_mourn_inferior' function
     gets called whenever the program exits.  However, suppose the
     program exits, and *then* the executable file changes?  We need
     to check again here.  Since reopen_exec_file doesn't do anything
     if the timestamp hasn't changed, I don't see the harm.  */
  reopen_exec_file ();
  reread_symbols ();

  exec_file = (char *) get_exec_file (0);

  /* We keep symbols from add-symbol-file, on the grounds that the
     user might want to add some symbols before running the program
     (right?).  But sometimes (dynamic loading where the user manually
     introduces the new symbols with add-symbol-file), the code which
     the symbols describe does not persist between runs.  Currently
     the user has to manually nuke all symbols between runs if they
     want them to go away (PR 2207).  This is probably reasonable.  */

  if (!args)
    {
      if (event_loop_p && target_can_async_p ())
	async_disable_stdin ();
    }
  else
    {
      int async_exec = strip_bg_char (&args);

      /* If we get a request for running in the bg but the target
         doesn't support it, error out. */
      if (event_loop_p && async_exec && !target_can_async_p ())
	error ("Asynchronous execution not supported on this target.");

      /* If we don't get a request of running in the bg, then we need
         to simulate synchronous (fg) execution. */
      if (event_loop_p && !async_exec && target_can_async_p ())
	{
	  /* Simulate synchronous execution */
	  async_disable_stdin ();
	}

      /* If there were other args, beside '&', process them. */
      if (args)
	{
          char *old_args = set_inferior_args (xstrdup (args));
          xfree (old_args);
	}
    }

  if (from_tty)
    {
      ui_out_field_string (uiout, NULL, "Starting program");
      ui_out_text (uiout, ": ");
      if (exec_file)
	ui_out_field_string (uiout, "execfile", exec_file);
      ui_out_spaces (uiout, 1);
      /* We call get_inferior_args() because we might need to compute
	 the value now.  */
      ui_out_field_string (uiout, "infargs", get_inferior_args ());
      ui_out_text (uiout, "\n");
      ui_out_flush (uiout);
    }

  /* We call get_inferior_args() because we might need to compute
     the value now.  */
  target_create_inferior (exec_file, get_inferior_args (),
			  environ_vector (inferior_environ));
}


static void
run_no_args_command (char *args, int from_tty)
{
  char *old_args = set_inferior_args (xstrdup (""));
  xfree (old_args);
}


void
continue_command (char *proc_count_exp, int from_tty)
{
  int async_exec = 0;
  ERROR_NO_INFERIOR;

  /* Find out whether we must run in the background. */
  if (proc_count_exp != NULL)
    async_exec = strip_bg_char (&proc_count_exp);

  /* If we must run in the background, but the target can't do it,
     error out. */
  if (event_loop_p && async_exec && !target_can_async_p ())
    error ("Asynchronous execution not supported on this target.");

  /* If we are not asked to run in the bg, then prepare to run in the
     foreground, synchronously. */
  if (event_loop_p && !async_exec && target_can_async_p ())
    {
      /* Simulate synchronous execution */
      async_disable_stdin ();
    }

  /* If have argument (besides '&'), set proceed count of breakpoint
     we stopped at.  */
  if (proc_count_exp != NULL)
    {
      bpstat bs = stop_bpstat;
      int num = bpstat_num (&bs);
      if (num == 0 && from_tty)
	{
	  printf_filtered
	    ("Not stopped at any breakpoint; argument ignored.\n");
	}
      while (num != 0)
	{
	  set_ignore_count (num,
			    parse_and_eval_long (proc_count_exp) - 1,
			    from_tty);
	  /* set_ignore_count prints a message ending with a period.
	     So print two spaces before "Continuing.".  */
	  if (from_tty)
	    printf_filtered ("  ");
	  num = bpstat_num (&bs);
	}
    }

  if (from_tty)
    printf_filtered ("Continuing.\n");

  clear_proceed_status ();

  proceed ((CORE_ADDR) -1, TARGET_SIGNAL_DEFAULT, 0);
}

/* Step until outside of current statement.  */

/* ARGSUSED */
static void
step_command (char *count_string, int from_tty)
{
  step_1 (0, 0, count_string);
}

/* Likewise, but skip over subroutine calls as if single instructions.  */

/* ARGSUSED */
static void
next_command (char *count_string, int from_tty)
{
  step_1 (1, 0, count_string);
}

/* Likewise, but step only one instruction.  */

/* ARGSUSED */
void
stepi_command (char *count_string, int from_tty)
{
  step_1 (0, 1, count_string);
}

/* ARGSUSED */
void
nexti_command (char *count_string, int from_tty)
{
  step_1 (1, 1, count_string);
}

static void
disable_longjmp_breakpoint_cleanup (void *ignore)
{
  disable_longjmp_breakpoint ();
}

static void
step_1 (int skip_subroutines, int single_inst, char *count_string)
{
  register int count = 1;
  struct frame_info *frame;
  struct cleanup *cleanups = 0;
  int async_exec = 0;

  ERROR_NO_INFERIOR;

  if (count_string)
    async_exec = strip_bg_char (&count_string);

  /* If we get a request for running in the bg but the target
     doesn't support it, error out. */
  if (event_loop_p && async_exec && !target_can_async_p ())
    error ("Asynchronous execution not supported on this target.");

  /* If we don't get a request of running in the bg, then we need
     to simulate synchronous (fg) execution. */
  if (event_loop_p && !async_exec && target_can_async_p ())
    {
      /* Simulate synchronous execution */
      async_disable_stdin ();
    }

  count = count_string ? parse_and_eval_long (count_string) : 1;

  if (!single_inst || skip_subroutines)		/* leave si command alone */
    {
      enable_longjmp_breakpoint ();
      if (!event_loop_p || !target_can_async_p ())
	cleanups = make_cleanup (disable_longjmp_breakpoint_cleanup, 0 /*ignore*/);
      else
        make_exec_cleanup (disable_longjmp_breakpoint_cleanup, 0 /*ignore*/);
    }

  /* In synchronous case, all is well, just use the regular for loop. */
  if (!event_loop_p || !target_can_async_p ())
    {
      for (; count > 0; count--)
	{
	  clear_proceed_status ();

	  frame = get_current_frame ();
	  if (!frame)		/* Avoid coredump here.  Why tho? */
	    error ("No current frame");
	  step_frame_address = FRAME_FP (frame);
	  step_sp = read_sp ();

	  if (!single_inst)
	    {
	      find_pc_line_pc_range (stop_pc, &step_range_start, &step_range_end);
	      if (step_range_end == 0)
		{
		  char *name;
		  if (find_pc_partial_function (stop_pc, &name, &step_range_start,
						&step_range_end) == 0)
		    error ("Cannot find bounds of current function");

		  target_terminal_ours ();
		  printf_filtered ("\
Single stepping until exit from function %s, \n\
which has no line number information.\n", name);
		}
	    }
	  else
	    {
	      /* Say we are stepping, but stop after one insn whatever it does.  */
	      step_range_start = step_range_end = 1;
	      if (!skip_subroutines)
		/* It is stepi.
		   Don't step over function calls, not even to functions lacking
		   line numbers.  */
		step_over_calls = STEP_OVER_NONE;
	    }

	  if (skip_subroutines)
	    step_over_calls = STEP_OVER_ALL;

	  step_multi = (count > 1);
	  proceed ((CORE_ADDR) -1, TARGET_SIGNAL_DEFAULT, 1);

	  if (!stop_step)
	    break;

	  /* FIXME: On nexti, this may have already been done (when we hit the
	     step resume break, I think).  Probably this should be moved to
	     wait_for_inferior (near the top).  */
#if defined (SHIFT_INST_REGS)
	  SHIFT_INST_REGS ();
#endif
	}

      if (!single_inst || skip_subroutines)
	do_cleanups (cleanups);
      return;
    }
  /* In case of asynchronous target things get complicated, do only
     one step for now, before returning control to the event loop. Let
     the continuation figure out how many other steps we need to do,
     and handle them one at the time, through step_once(). */
  else
    {
      if (event_loop_p && target_can_async_p ())
	step_once (skip_subroutines, single_inst, count);
    }
}

/* Called after we are done with one step operation, to check whether
   we need to step again, before we print the prompt and return control
   to the user. If count is > 1, we will need to do one more call to
   proceed(), via step_once(). Basically it is like step_once and
   step_1_continuation are co-recursive. */
static void
step_1_continuation (struct continuation_arg *arg)
{
  int count;
  int skip_subroutines;
  int single_inst;

  skip_subroutines = arg->data.integer;
  single_inst      = arg->next->data.integer;
  count            = arg->next->next->data.integer;

  if (stop_step)
    {
      /* FIXME: On nexti, this may have already been done (when we hit the
	 step resume break, I think).  Probably this should be moved to
	 wait_for_inferior (near the top).  */
#if defined (SHIFT_INST_REGS)
      SHIFT_INST_REGS ();
#endif
      step_once (skip_subroutines, single_inst, count - 1);
    }
  else
    if (!single_inst || skip_subroutines)
      do_exec_cleanups (ALL_CLEANUPS);
}

/* Do just one step operation. If count >1 we will have to set up a
   continuation to be done after the target stops (after this one
   step). This is useful to implement the 'step n' kind of commands, in
   case of asynchronous targets. We had to split step_1 into two parts,
   one to be done before proceed() and one afterwards. This function is
   called in case of step n with n>1, after the first step operation has
   been completed.*/
static void 
step_once (int skip_subroutines, int single_inst, int count)
{ 
  struct continuation_arg *arg1; 
  struct continuation_arg *arg2;
  struct continuation_arg *arg3; 
  struct frame_info *frame;

  if (count > 0)
    {
      clear_proceed_status ();

      frame = get_current_frame ();
      if (!frame)		/* Avoid coredump here.  Why tho? */
	error ("No current frame");
      step_frame_address = FRAME_FP (frame);
      step_sp = read_sp ();

      if (!single_inst)
	{
	  find_pc_line_pc_range (stop_pc, &step_range_start, &step_range_end);

	  /* If we have no line info, switch to stepi mode.  */
	  if (step_range_end == 0 && step_stop_if_no_debug)
	    {
	      step_range_start = step_range_end = 1;
	    }
	  else if (step_range_end == 0)
	    {
	      char *name;
	      if (find_pc_partial_function (stop_pc, &name, &step_range_start,
					    &step_range_end) == 0)
		error ("Cannot find bounds of current function");

	      target_terminal_ours ();
	      printf_filtered ("\
Single stepping until exit from function %s, \n\
which has no line number information.\n", name);
	    }
	}
      else
	{
	  /* Say we are stepping, but stop after one insn whatever it does.  */
	  step_range_start = step_range_end = 1;
	  if (!skip_subroutines)
	    /* It is stepi.
	       Don't step over function calls, not even to functions lacking
	       line numbers.  */
	    step_over_calls = STEP_OVER_NONE;
	}

      if (skip_subroutines)
	step_over_calls = STEP_OVER_ALL;

      step_multi = (count > 1);
      arg1 =
	(struct continuation_arg *) xmalloc (sizeof (struct continuation_arg));
      arg2 =
	(struct continuation_arg *) xmalloc (sizeof (struct continuation_arg));
      arg3 =
	(struct continuation_arg *) xmalloc (sizeof (struct continuation_arg));
      arg1->next = arg2;
      arg1->data.integer = skip_subroutines;
      arg2->next = arg3;
      arg2->data.integer = single_inst;
      arg3->next = NULL;
      arg3->data.integer = count;
      add_intermediate_continuation (step_1_continuation, arg1);
      proceed ((CORE_ADDR) -1, TARGET_SIGNAL_DEFAULT, 1);
    }
}


/* Continue program at specified address.  */

static void
jump_command (char *arg, int from_tty)
{
  register CORE_ADDR addr;
  struct symtabs_and_lines sals;
  struct symtab_and_line sal;
  struct symbol *fn;
  struct symbol *sfn;
  int async_exec = 0;

  ERROR_NO_INFERIOR;

  /* Find out whether we must run in the background. */
  if (arg != NULL)
    async_exec = strip_bg_char (&arg);

  /* If we must run in the background, but the target can't do it,
     error out. */
  if (event_loop_p && async_exec && !target_can_async_p ())
    error ("Asynchronous execution not supported on this target.");

  /* If we are not asked to run in the bg, then prepare to run in the
     foreground, synchronously. */
  if (event_loop_p && !async_exec && target_can_async_p ())
    {
      /* Simulate synchronous execution */
      async_disable_stdin ();
    }

  if (!arg)
    error_no_arg ("starting address");

  sals = decode_line_spec_1 (arg, 1);
  if (sals.nelts != 1)
    {
      error ("Unreasonable jump request");
    }

  sal = sals.sals[0];
  xfree (sals.sals);

  if (sal.symtab == 0 && sal.pc == 0)
    error ("No source file has been specified.");

  resolve_sal_pc (&sal);	/* May error out */

  /* See if we are trying to jump to another function. */
  fn = get_frame_function (get_current_frame ());
  sfn = find_pc_function (sal.pc);
  if (fn != NULL && sfn != fn)
    {
      if (!query ("Line %d is not in `%s'.  Jump anyway? ", sal.line,
		  SYMBOL_SOURCE_NAME (fn)))
	{
	  error ("Not confirmed.");
	  /* NOTREACHED */
	}
    }

  if (sfn != NULL)
    {
      fixup_symbol_section (sfn, 0);
      if (section_is_overlay (SYMBOL_BFD_SECTION (sfn)) &&
	  !section_is_mapped (SYMBOL_BFD_SECTION (sfn)))
	{
	  if (!query ("WARNING!!!  Destination is in unmapped overlay!  Jump anyway? "))
	    {
	      error ("Not confirmed.");
	      /* NOTREACHED */
	    }
	}
    }

  addr = sal.pc;

  if (from_tty)
    {
      printf_filtered ("Continuing at ");
      print_address_numeric (addr, 1, gdb_stdout);
      printf_filtered (".\n");
    }

  clear_proceed_status ();
  proceed (addr, TARGET_SIGNAL_0, 0);
}


/* Go to line or address in current procedure */
static void
go_command (char *line_no, int from_tty)
{
  if (line_no == (char *) NULL || !*line_no)
    printf_filtered (GO_USAGE);
  else
    {
      tbreak_command (line_no, from_tty);
      jump_command (line_no, from_tty);
    }
}


/* Continue program giving it specified signal.  */

static void
signal_command (char *signum_exp, int from_tty)
{
  enum target_signal oursig;

  dont_repeat ();		/* Too dangerous.  */
  ERROR_NO_INFERIOR;

  if (!signum_exp)
    error_no_arg ("signal number");

  /* It would be even slicker to make signal names be valid expressions,
     (the type could be "enum $signal" or some such), then the user could
     assign them to convenience variables.  */
  oursig = target_signal_from_name (signum_exp);

  if (oursig == TARGET_SIGNAL_UNKNOWN)
    {
      /* No, try numeric.  */
      int num = parse_and_eval_long (signum_exp);

      if (num == 0)
	oursig = TARGET_SIGNAL_0;
      else
	oursig = target_signal_from_command (num);
    }

  if (from_tty)
    {
      if (oursig == TARGET_SIGNAL_0)
	printf_filtered ("Continuing with no signal.\n");
      else
	printf_filtered ("Continuing with signal %s.\n",
			 target_signal_to_name (oursig));
    }

  clear_proceed_status ();
  /* "signal 0" should not get stuck if we are stopped at a breakpoint.
     FIXME: Neither should "signal foo" but when I tried passing
     (CORE_ADDR)-1 unconditionally I got a testsuite failure which I haven't
     tried to track down yet.  */
  proceed (oursig == TARGET_SIGNAL_0 ? (CORE_ADDR) -1 : stop_pc, oursig, 0);
}

/* Call breakpoint_auto_delete on the current contents of the bpstat
   pointed to by arg (which is really a bpstat *).  */

static void
breakpoint_auto_delete_contents (PTR arg)
{
  breakpoint_auto_delete (*(bpstat *) arg);
}


/* Execute a "stack dummy", a piece of code stored in the stack
   by the debugger to be executed in the inferior.

   To call: first, do PUSH_DUMMY_FRAME.
   Then push the contents of the dummy.  It should end with a breakpoint insn.
   Then call here, passing address at which to start the dummy.

   The contents of all registers are saved before the dummy frame is popped
   and copied into the buffer BUFFER.

   The dummy's frame is automatically popped whenever that break is hit.
   If that is the first time the program stops, run_stack_dummy
   returns to its caller with that frame already gone and returns 0.
   
   Otherwise, run_stack-dummy returns a non-zero value.
   If the called function receives a random signal, we do not allow the user
   to continue executing it as this may not work.  The dummy frame is poped
   and we return 1.
   If we hit a breakpoint, we leave the frame in place and return 2 (the frame
   will eventually be popped when we do hit the dummy end breakpoint).  */

int
run_stack_dummy (CORE_ADDR addr, char *buffer)
{
  struct cleanup *old_cleanups = make_cleanup (null_cleanup, 0);
  int saved_async = 0;

  /* Now proceed, having reached the desired place.  */
  clear_proceed_status ();

  if (CALL_DUMMY_BREAKPOINT_OFFSET_P)
    {
      struct breakpoint *bpt;
      struct symtab_and_line sal;

      INIT_SAL (&sal);		/* initialize to zeroes */
      if (CALL_DUMMY_LOCATION == AT_ENTRY_POINT)
	{
	  sal.pc = CALL_DUMMY_ADDRESS ();
	}
      else
	{
	  sal.pc = addr - CALL_DUMMY_START_OFFSET + CALL_DUMMY_BREAKPOINT_OFFSET;
	}
      sal.section = find_pc_overlay (sal.pc);

      /* Set up a FRAME for the dummy frame so we can pass it to
         set_momentary_breakpoint.  We need to give the breakpoint a
         frame in case there is only one copy of the dummy (e.g.
         CALL_DUMMY_LOCATION == AFTER_TEXT_END).  */
      flush_cached_frames ();
      set_current_frame (create_new_frame (read_fp (), sal.pc));

      /* If defined, CALL_DUMMY_BREAKPOINT_OFFSET is where we need to put
         a breakpoint instruction.  If not, the call dummy already has the
         breakpoint instruction in it.

         addr is the address of the call dummy plus the CALL_DUMMY_START_OFFSET,
         so we need to subtract the CALL_DUMMY_START_OFFSET.  */
      bpt = set_momentary_breakpoint (sal,
				      get_current_frame (),
				      bp_call_dummy);
      bpt->disposition = disp_del;

      /* If all error()s out of proceed ended up calling normal_stop (and
         perhaps they should; it already does in the special case of error
         out of resume()), then we wouldn't need this.  */
      make_cleanup (breakpoint_auto_delete_contents, &stop_bpstat);
    }

  disable_watchpoints_before_interactive_call_start ();
  proceed_to_finish = 1;	/* We want stop_registers, please... */

  if (target_can_async_p ())
    saved_async = target_async_mask (0);

  proceed (addr, TARGET_SIGNAL_0, 0);

  if (saved_async)
    target_async_mask (saved_async);

  enable_watchpoints_after_interactive_call_stop ();

  discard_cleanups (old_cleanups);

  /* We can stop during an inferior call because a signal is received. */
  if (stopped_by_random_signal)
    return 1;
    
  /* We may also stop prematurely because we hit a breakpoint in the
     called routine. */
  if (!stop_stack_dummy)
    return 2;

  /* On normal return, the stack dummy has been popped already.  */

  memcpy (buffer, stop_registers, REGISTER_BYTES);
  return 0;
}

/* Proceed until we reach a different source line with pc greater than
   our current one or exit the function.  We skip calls in both cases.

   Note that eventually this command should probably be changed so
   that only source lines are printed out when we hit the breakpoint
   we set.  This may involve changes to wait_for_inferior and the
   proceed status code.  */

/* ARGSUSED */
static void
until_next_command (int from_tty)
{
  struct frame_info *frame;
  CORE_ADDR pc;
  struct symbol *func;
  struct symtab_and_line sal;

  clear_proceed_status ();

  frame = get_current_frame ();

  /* Step until either exited from this function or greater
     than the current line (if in symbolic section) or pc (if
     not). */

  pc = read_pc ();
  func = find_pc_function (pc);

  if (!func)
    {
      struct minimal_symbol *msymbol = lookup_minimal_symbol_by_pc (pc);

      if (msymbol == NULL)
	error ("Execution is not within a known function.");

      step_range_start = SYMBOL_VALUE_ADDRESS (msymbol);
      step_range_end = pc;
    }
  else
    {
      sal = find_pc_line (pc, 0);

      step_range_start = BLOCK_START (SYMBOL_BLOCK_VALUE (func));
      step_range_end = sal.end;
    }

  step_over_calls = STEP_OVER_ALL;
  step_frame_address = FRAME_FP (frame);
  step_sp = read_sp ();

  step_multi = 0;		/* Only one call to proceed */

  proceed ((CORE_ADDR) -1, TARGET_SIGNAL_DEFAULT, 1);
}

static void
until_command (char *arg, int from_tty)
{
  int async_exec = 0;

  if (!target_has_execution)
    error ("The program is not running.");

  /* Find out whether we must run in the background. */
  if (arg != NULL)
    async_exec = strip_bg_char (&arg);

  /* If we must run in the background, but the target can't do it,
     error out. */
  if (event_loop_p && async_exec && !target_can_async_p ())
    error ("Asynchronous execution not supported on this target.");

  /* If we are not asked to run in the bg, then prepare to run in the
     foreground, synchronously. */
  if (event_loop_p && !async_exec && target_can_async_p ())
    {
      /* Simulate synchronous execution */
      async_disable_stdin ();
    }

  if (arg)
    until_break_command (arg, from_tty);
  else
    until_next_command (from_tty);
}


/* Print the result of a function at the end of a 'finish' command. */
static void
print_return_value (int structure_return, struct type *value_type)
{
  struct value *value;
  static struct ui_stream *stb = NULL;

  if (!structure_return)
    {
      value = value_being_returned (value_type, stop_registers, structure_return);
      stb = ui_out_stream_new (uiout);
      ui_out_text (uiout, "Value returned is ");
      ui_out_field_fmt (uiout, "gdb-result-var", "$%d", record_latest_value (value));
      ui_out_text (uiout, " = ");
      value_print (value, stb->stream, 0, Val_no_prettyprint);
      ui_out_field_stream (uiout, "return-value", stb);
      ui_out_text (uiout, "\n");
    }
  else
    {
      /* We cannot determine the contents of the structure because
	 it is on the stack, and we don't know where, since we did not
	 initiate the call, as opposed to the call_function_by_hand case */
#ifdef VALUE_RETURNED_FROM_STACK
      value = 0;
      ui_out_text (uiout, "Value returned has type: ");
      ui_out_field_string (uiout, "return-type", TYPE_NAME (value_type));
      ui_out_text (uiout, ".");
      ui_out_text (uiout, " Cannot determine contents\n");
#else
      value = value_being_returned (value_type, stop_registers, structure_return);
      stb = ui_out_stream_new (uiout);
      ui_out_text (uiout, "Value returned is ");
      ui_out_field_fmt (uiout, "gdb-result-var", "$%d", record_latest_value (value));
      ui_out_text (uiout, " = ");
      value_print (value, stb->stream, 0, Val_no_prettyprint);
      ui_out_field_stream (uiout, "return-value", stb);
      ui_out_text (uiout, "\n");
#endif
    }
}

/* Stuff that needs to be done by the finish command after the target
   has stopped.  In asynchronous mode, we wait for the target to stop in
   the call to poll or select in the event loop, so it is impossible to
   do all the stuff as part of the finish_command function itself. The
   only chance we have to complete this command is in
   fetch_inferior_event, which is called by the event loop as soon as it
   detects that the target has stopped. This function is called via the
   cmd_continuation pointer. */
void
finish_command_continuation (struct continuation_arg *arg)
{
  register struct symbol *function;
  struct breakpoint *breakpoint;
  struct cleanup *cleanups;

  breakpoint = (struct breakpoint *) arg->data.pointer;
  function   = (struct symbol *)     arg->next->data.pointer;
  cleanups   = (struct cleanup *)    arg->next->next->data.pointer;

  if (bpstat_find_breakpoint (stop_bpstat, breakpoint) != NULL
      && function != 0)
    {
      struct type *value_type;
      CORE_ADDR funcaddr;
      int struct_return;

      value_type = TYPE_TARGET_TYPE (SYMBOL_TYPE (function));
      if (!value_type)
	internal_error (__FILE__, __LINE__,
			"finish_command: function has no target type");

      if (TYPE_CODE (value_type) == TYPE_CODE_VOID)
	{
	  do_exec_cleanups (cleanups);
	  return;
	}

      funcaddr = BLOCK_START (SYMBOL_BLOCK_VALUE (function));

      struct_return = using_struct_return (value_of_variable (function, NULL),
					   funcaddr,
					   check_typedef (value_type),
					   BLOCK_GCC_COMPILED (SYMBOL_BLOCK_VALUE (function)));

      print_return_value (struct_return, value_type); 
    }
  do_exec_cleanups (cleanups);
}

/* "finish": Set a temporary breakpoint at the place
   the selected frame will return to, then continue.  */

static void
finish_command (char *arg, int from_tty)
{
  struct symtab_and_line sal;
  register struct frame_info *frame;
  register struct symbol *function;
  struct breakpoint *breakpoint;
  struct cleanup *old_chain;
  struct continuation_arg *arg1, *arg2, *arg3;

  int async_exec = 0;

  /* Find out whether we must run in the background. */
  if (arg != NULL)
    async_exec = strip_bg_char (&arg);

  /* If we must run in the background, but the target can't do it,
     error out. */
  if (event_loop_p && async_exec && !target_can_async_p ())
    error ("Asynchronous execution not supported on this target.");

  /* If we are not asked to run in the bg, then prepare to run in the
     foreground, synchronously. */
  if (event_loop_p && !async_exec && target_can_async_p ())
    {
      /* Simulate synchronous execution */
      async_disable_stdin ();
    }

  if (arg)
    error ("The \"finish\" command does not take any arguments.");
  if (!target_has_execution)
    error ("The program is not running.");
  if (selected_frame == NULL)
    error ("No selected frame.");

  frame = get_prev_frame (selected_frame);
  if (frame == 0)
    error ("\"finish\" not meaningful in the outermost frame.");

  clear_proceed_status ();

  sal = find_pc_line (frame->pc, 0);
  sal.pc = frame->pc;

  breakpoint = set_momentary_breakpoint (sal, frame, bp_finish);

  if (!event_loop_p || !target_can_async_p ())
    old_chain = make_cleanup_delete_breakpoint (breakpoint);
  else
    old_chain = make_exec_cleanup_delete_breakpoint (breakpoint);

  /* Find the function we will return from.  */

  function = find_pc_function (selected_frame->pc);

  /* Print info on the selected frame, including level number
     but not source.  */
  if (from_tty)
    {
      printf_filtered ("Run till exit from ");
      print_stack_frame (selected_frame, selected_frame_level, 0);
    }

  /* If running asynchronously and the target support asynchronous
     execution, set things up for the rest of the finish command to be
     completed later on, when gdb has detected that the target has
     stopped, in fetch_inferior_event. */
  if (event_loop_p && target_can_async_p ())
    {
      arg1 =
	(struct continuation_arg *) xmalloc (sizeof (struct continuation_arg));
      arg2 =
	(struct continuation_arg *) xmalloc (sizeof (struct continuation_arg));
      arg3 =
	(struct continuation_arg *) xmalloc (sizeof (struct continuation_arg));
      arg1->next = arg2;
      arg2->next = arg3;
      arg3->next = NULL;
      arg1->data.pointer = breakpoint;
      arg2->data.pointer = function;
      arg3->data.pointer = old_chain;
      add_continuation (finish_command_continuation, arg1);
    }

  proceed_to_finish = 1;	/* We want stop_registers, please... */
  proceed ((CORE_ADDR) -1, TARGET_SIGNAL_DEFAULT, 0);

  /* Do this only if not running asynchronously or if the target
     cannot do async execution. Otherwise, complete this command when
     the target actually stops, in fetch_inferior_event. */
  if (!event_loop_p || !target_can_async_p ())
    {

      /* Did we stop at our breakpoint? */
      if (bpstat_find_breakpoint (stop_bpstat, breakpoint) != NULL
	  && function != 0)
	{
	  struct type *value_type;
	  CORE_ADDR funcaddr;
	  int struct_return;

	  value_type = TYPE_TARGET_TYPE (SYMBOL_TYPE (function));
	  if (!value_type)
	    internal_error (__FILE__, __LINE__,
			    "finish_command: function has no target type");

	  /* FIXME: Shouldn't we do the cleanups before returning? */
	  if (TYPE_CODE (value_type) == TYPE_CODE_VOID)
	    return;

	  funcaddr = BLOCK_START (SYMBOL_BLOCK_VALUE (function));

	  struct_return =
	    using_struct_return (value_of_variable (function, NULL),
				 funcaddr,
				 check_typedef (value_type),
			BLOCK_GCC_COMPILED (SYMBOL_BLOCK_VALUE (function)));

	  print_return_value (struct_return, value_type); 
	}
      do_cleanups (old_chain);
    }
}

/* ARGSUSED */
static void
program_info (char *args, int from_tty)
{
  bpstat bs = stop_bpstat;
  int num = bpstat_num (&bs);

  if (!target_has_execution)
    {
      printf_filtered ("The program being debugged is not being run.\n");
      return;
    }

  target_files_info ();
  printf_filtered ("Program stopped at %s.\n",
		   local_hex_string ((unsigned long) stop_pc));
  if (stop_step)
    printf_filtered ("It stopped after being stepped.\n");
  else if (num != 0)
    {
      /* There may be several breakpoints in the same place, so this
         isn't as strange as it seems.  */
      while (num != 0)
	{
	  if (num < 0)
	    {
	      printf_filtered ("It stopped at a breakpoint that has ");
	      printf_filtered ("since been deleted.\n");
	    }
	  else
	    printf_filtered ("It stopped at breakpoint %d.\n", num);
	  num = bpstat_num (&bs);
	}
    }
  else if (stop_signal != TARGET_SIGNAL_0)
    {
      printf_filtered ("It stopped with signal %s, %s.\n",
		       target_signal_to_name (stop_signal),
		       target_signal_to_string (stop_signal));
    }

  if (!from_tty)
    {
      printf_filtered ("Type \"info stack\" or \"info registers\" ");
      printf_filtered ("for more information.\n");
    }
}

static void
environment_info (char *var, int from_tty)
{
  if (var)
    {
      register char *val = get_in_environ (inferior_environ, var);
      if (val)
	{
	  puts_filtered (var);
	  puts_filtered (" = ");
	  puts_filtered (val);
	  puts_filtered ("\n");
	}
      else
	{
	  puts_filtered ("Environment variable \"");
	  puts_filtered (var);
	  puts_filtered ("\" not defined.\n");
	}
    }
  else
    {
      register char **vector = environ_vector (inferior_environ);
      while (*vector)
	{
	  puts_filtered (*vector++);
	  puts_filtered ("\n");
	}
    }
}

static void
set_environment_command (char *arg, int from_tty)
{
  register char *p, *val, *var;
  int nullset = 0;

  if (arg == 0)
    error_no_arg ("environment variable and value");

  /* Find seperation between variable name and value */
  p = (char *) strchr (arg, '=');
  val = (char *) strchr (arg, ' ');

  if (p != 0 && val != 0)
    {
      /* We have both a space and an equals.  If the space is before the
         equals, walk forward over the spaces til we see a nonspace 
         (possibly the equals). */
      if (p > val)
	while (*val == ' ')
	  val++;

      /* Now if the = is after the char following the spaces,
         take the char following the spaces.  */
      if (p > val)
	p = val - 1;
    }
  else if (val != 0 && p == 0)
    p = val;

  if (p == arg)
    error_no_arg ("environment variable to set");

  if (p == 0 || p[1] == 0)
    {
      nullset = 1;
      if (p == 0)
	p = arg + strlen (arg);	/* So that savestring below will work */
    }
  else
    {
      /* Not setting variable value to null */
      val = p + 1;
      while (*val == ' ' || *val == '\t')
	val++;
    }

  while (p != arg && (p[-1] == ' ' || p[-1] == '\t'))
    p--;

  var = savestring (arg, p - arg);
  if (nullset)
    {
      printf_filtered ("Setting environment variable ");
      printf_filtered ("\"%s\" to null value.\n", var);
      set_in_environ (inferior_environ, var, "");
    }
  else
    set_in_environ (inferior_environ, var, val);
  xfree (var);
}

static void
unset_environment_command (char *var, int from_tty)
{
  if (var == 0)
    {
      /* If there is no argument, delete all environment variables.
         Ask for confirmation if reading from the terminal.  */
      if (!from_tty || query ("Delete all environment variables? "))
	{
	  free_environ (inferior_environ);
	  inferior_environ = make_environ ();
	}
    }
  else
    unset_in_environ (inferior_environ, var);
}

/* Handle the execution path (PATH variable) */

static const char path_var_name[] = "PATH";

/* ARGSUSED */
static void
path_info (char *args, int from_tty)
{
  puts_filtered ("Executable and object file path: ");
  puts_filtered (get_in_environ (inferior_environ, path_var_name));
  puts_filtered ("\n");
}

/* Add zero or more directories to the front of the execution path.  */

static void
path_command (char *dirname, int from_tty)
{
  char *exec_path;
  char *env;
  dont_repeat ();
  env = get_in_environ (inferior_environ, path_var_name);
  /* Can be null if path is not set */
  if (!env)
    env = "";
  exec_path = xstrdup (env);
  mod_path (dirname, &exec_path);
  set_in_environ (inferior_environ, path_var_name, exec_path);
  xfree (exec_path);
  if (from_tty)
    path_info ((char *) NULL, from_tty);
}


#ifdef REGISTER_NAMES
char *gdb_register_names[] = REGISTER_NAMES;
#endif
/* Print out the machine register regnum. If regnum is -1,
   print all registers (fpregs == 1) or all non-float registers
   (fpregs == 0).

   For most machines, having all_registers_info() print the
   register(s) one per line is good enough. If a different format
   is required, (eg, for MIPS or Pyramid 90x, which both have
   lots of regs), or there is an existing convention for showing
   all the registers, define the macro DO_REGISTERS_INFO(regnum, fp)
   to provide that format.  */

void
do_registers_info (int regnum, int fpregs)
{
  register int i;
  int numregs = NUM_REGS + NUM_PSEUDO_REGS;
  char *raw_buffer = (char*) alloca (MAX_REGISTER_RAW_SIZE);
  char *virtual_buffer = (char*) alloca (MAX_REGISTER_VIRTUAL_SIZE);

  for (i = 0; i < numregs; i++)
    {
      /* Decide between printing all regs, nonfloat regs, or specific reg.  */
      if (regnum == -1)
	{
	  if (TYPE_CODE (REGISTER_VIRTUAL_TYPE (i)) == TYPE_CODE_FLT && !fpregs)
	    continue;
	}
      else
	{
	  if (i != regnum)
	    continue;
	}

      /* If the register name is empty, it is undefined for this
         processor, so don't display anything.  */
      if (REGISTER_NAME (i) == NULL || *(REGISTER_NAME (i)) == '\0')
	continue;

      fputs_filtered (REGISTER_NAME (i), gdb_stdout);
      print_spaces_filtered (15 - strlen (REGISTER_NAME (i)), gdb_stdout);

      /* Get the data in raw format.  */
      if (! frame_register_read (selected_frame, i, raw_buffer))
	{
	  printf_filtered ("*value not available*\n");
	  continue;
	}

      /* Convert raw data to virtual format if necessary.  */
      if (REGISTER_CONVERTIBLE (i))
	{
	  REGISTER_CONVERT_TO_VIRTUAL (i, REGISTER_VIRTUAL_TYPE (i),
				       raw_buffer, virtual_buffer);
	}
      else
	{
	  memcpy (virtual_buffer, raw_buffer,
		  REGISTER_VIRTUAL_SIZE (i));
	}

      /* If virtual format is floating, print it that way, and in raw hex.  */
      if (TYPE_CODE (REGISTER_VIRTUAL_TYPE (i)) == TYPE_CODE_FLT)
	{
	  register int j;

	  val_print (REGISTER_VIRTUAL_TYPE (i), virtual_buffer, 0, 0,
		     gdb_stdout, 0, 1, 0, Val_pretty_default);

	  printf_filtered ("\t(raw 0x");
	  for (j = 0; j < REGISTER_RAW_SIZE (i); j++)
	    {
	      register int idx = TARGET_BYTE_ORDER == BFD_ENDIAN_BIG ? j
	      : REGISTER_RAW_SIZE (i) - 1 - j;
	      printf_filtered ("%02x", (unsigned char) raw_buffer[idx]);
	    }
	  printf_filtered (")");
	}
      /* Else print as integer in hex and in decimal.  */
      else
	{
	  val_print (REGISTER_VIRTUAL_TYPE (i), virtual_buffer, 0, 0,
		     gdb_stdout, 'x', 1, 0, Val_pretty_default);
	  printf_filtered ("\t");
	  val_print (REGISTER_VIRTUAL_TYPE (i), virtual_buffer, 0, 0,
		     gdb_stdout, 0, 1, 0, Val_pretty_default);
	}

      /* The SPARC wants to print even-numbered float regs as doubles
         in addition to printing them as floats.  */
#ifdef PRINT_REGISTER_HOOK
      PRINT_REGISTER_HOOK (i);
#endif

      printf_filtered ("\n");
    }
}

void
registers_info (char *addr_exp, int fpregs)
{
  int regnum, numregs;
  register char *end;

  if (!target_has_registers)
    error ("The program has no registers now.");
  if (selected_frame == NULL)
    error ("No selected frame.");

  if (!addr_exp)
    {
      DO_REGISTERS_INFO (-1, fpregs);
      return;
    }

  do
    {
      if (addr_exp[0] == '$')
	addr_exp++;
      end = addr_exp;
      while (*end != '\0' && *end != ' ' && *end != '\t')
	++end;
      numregs = NUM_REGS + NUM_PSEUDO_REGS;

      regnum = target_map_name_to_register (addr_exp, end - addr_exp);
      if (regnum >= 0)
	goto found;

      regnum = numregs;

      if (*addr_exp >= '0' && *addr_exp <= '9')
	regnum = atoi (addr_exp);	/* Take a number */
      if (regnum >= numregs)	/* Bad name, or bad number */
	error ("%.*s: invalid register", end - addr_exp, addr_exp);

    found:
      DO_REGISTERS_INFO (regnum, fpregs);

      addr_exp = end;
      while (*addr_exp == ' ' || *addr_exp == '\t')
	++addr_exp;
    }
  while (*addr_exp != '\0');
}

void
all_registers_info (char *addr_exp, int from_tty)
{
  registers_info (addr_exp, 1);
}

void
nofp_registers_info (char *addr_exp, int from_tty)
{
  registers_info (addr_exp, 0);
}


/*
 * TODO:
 * Should save/restore the tty state since it might be that the
 * program to be debugged was started on this tty and it wants
 * the tty in some state other than what we want.  If it's running
 * on another terminal or without a terminal, then saving and
 * restoring the tty state is a harmless no-op.
 * This only needs to be done if we are attaching to a process.
 */

/*
   attach_command --
   takes a program started up outside of gdb and ``attaches'' to it.
   This stops it cold in its tracks and allows us to start debugging it.
   and wait for the trace-trap that results from attaching.  */

void
attach_command (char *args, int from_tty)
{
  char *exec_file;
  char *full_exec_path = NULL;

  dont_repeat ();		/* Not for the faint of heart */

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

  target_attach (args, from_tty);

  /* Set up the "saved terminal modes" of the inferior
     based on what modes we are starting it with.  */
  target_terminal_init ();

  /* Install inferior's terminal modes.  */
  target_terminal_inferior ();

  /* Set up execution context to know that we should return from
     wait_for_inferior as soon as the target reports a stop.  */
  init_wait_for_inferior ();
  clear_proceed_status ();

  /* No traps are generated when attaching to inferior under Mach 3
     or GNU hurd.  */
#ifndef ATTACH_NO_WAIT
  stop_soon_quietly = 1;
  wait_for_inferior ();
#endif

  /*
   * If no exec file is yet known, try to determine it from the
   * process itself.
   */
  exec_file = (char *) get_exec_file (0);
  if (!exec_file)
    {
      exec_file = target_pid_to_exec_file (PIDGET (inferior_ptid));
      if (exec_file)
	{
	  /* It's possible we don't have a full path, but rather just a
	     filename.  Some targets, such as HP-UX, don't provide the
	     full path, sigh.

	     Attempt to qualify the filename against the source path.
	     (If that fails, we'll just fall back on the original
	     filename.  Not much more we can do...)
	   */
	  if (!source_full_path_of (exec_file, &full_exec_path))
	    full_exec_path = savestring (exec_file, strlen (exec_file));

	  exec_file_attach (full_exec_path, from_tty);
	  symbol_file_add_main (full_exec_path, from_tty);
	}
    }

#ifdef SOLIB_ADD
  /* Add shared library symbols from the newly attached process, if any.  */
  SOLIB_ADD ((char *) 0, from_tty, &current_target, auto_solib_add);
  re_enable_breakpoints_in_shlibs ();
#endif

  /* Take any necessary post-attaching actions for this platform.
   */
  target_post_attach (PIDGET (inferior_ptid));

  normal_stop ();

  if (attach_hook)
    attach_hook ();
}

/*
 * detach_command --
 * takes a program previously attached to and detaches it.
 * The program resumes execution and will no longer stop
 * on signals, etc.  We better not have left any breakpoints
 * in the program or it'll die when it hits one.  For this
 * to work, it may be necessary for the process to have been
 * previously attached.  It *might* work if the program was
 * started via the normal ptrace (PTRACE_TRACEME).
 */

static void
detach_command (char *args, int from_tty)
{
  dont_repeat ();		/* Not for the faint of heart */
  target_detach (args, from_tty);
#if defined(SOLIB_RESTART)
  SOLIB_RESTART ();
#endif
  if (detach_hook)
    detach_hook ();
}

/* Stop the execution of the target while running in async mode, in
   the backgound. */

void
interrupt_target_command_wrapper (char *args, int from_tty)
{
  interrupt_target_command (args, from_tty);
}

static void
interrupt_target_command (char *args, int from_tty)
{
  if (event_loop_p && target_can_async_p ())
    {
      dont_repeat ();		/* Not for the faint of heart */
      target_stop ();
    }
}

/* ARGSUSED */
static void
float_info (char *addr_exp, int from_tty)
{
  PRINT_FLOAT_INFO ();
}

/* ARGSUSED */
static void
unset_command (char *args, int from_tty)
{
  printf_filtered ("\"unset\" must be followed by the name of ");
  printf_filtered ("an unset subcommand.\n");
  help_list (unsetlist, "unset ", -1, gdb_stdout);
}

void
_initialize_infcmd (void)
{
  struct cmd_list_element *c;

  c = add_com ("tty", class_run, tty_command,
	       "Set terminal for future runs of program being debugged.");
  set_cmd_completer (c, filename_completer);

  c = add_set_cmd ("args", class_run, var_string_noescape,
		   (char *) &inferior_args,
		   "Set argument list to give program being debugged when it is started.\n\
Follow this command with any number of args, to be passed to the program.",
		   &setlist);
  set_cmd_completer (c, filename_completer);
  set_cmd_sfunc (c, notice_args_set);
  c = add_show_from_set (c, &showlist);
  set_cmd_sfunc (c, notice_args_read);

  c = add_cmd
    ("environment", no_class, environment_info,
     "The environment to give the program, or one variable's value.\n\
With an argument VAR, prints the value of environment variable VAR to\n\
give the program being debugged.  With no arguments, prints the entire\n\
environment to be given to the program.", &showlist);
  set_cmd_completer (c, noop_completer);

  add_prefix_cmd ("unset", no_class, unset_command,
		  "Complement to certain \"set\" commands.",
		  &unsetlist, "unset ", 0, &cmdlist);

  c = add_cmd ("environment", class_run, unset_environment_command,
	       "Cancel environment variable VAR for the program.\n\
This does not affect the program until the next \"run\" command.",
	       &unsetlist);
  set_cmd_completer (c, noop_completer);

  c = add_cmd ("environment", class_run, set_environment_command,
	       "Set environment variable value to give the program.\n\
Arguments are VAR VALUE where VAR is variable name and VALUE is value.\n\
VALUES of environment variables are uninterpreted strings.\n\
This does not affect the program until the next \"run\" command.",
	       &setlist);
  set_cmd_completer (c, noop_completer);

  c = add_com ("path", class_files, path_command,
	       "Add directory DIR(s) to beginning of search path for object files.\n\
$cwd in the path means the current working directory.\n\
This path is equivalent to the $PATH shell variable.  It is a list of\n\
directories, separated by colons.  These directories are searched to find\n\
fully linked executable files and separately compiled object files as needed.");
  set_cmd_completer (c, filename_completer);

  c = add_cmd ("paths", no_class, path_info,
	       "Current search path for finding object files.\n\
$cwd in the path means the current working directory.\n\
This path is equivalent to the $PATH shell variable.  It is a list of\n\
directories, separated by colons.  These directories are searched to find\n\
fully linked executable files and separately compiled object files as needed.",
	       &showlist);
  set_cmd_completer (c, noop_completer);

  add_com ("attach", class_run, attach_command,
	   "Attach to a process or file outside of GDB.\n\
This command attaches to another target, of the same type as your last\n\
\"target\" command (\"info files\" will show your target stack).\n\
The command may take as argument a process id or a device file.\n\
For a process id, you must have permission to send the process a signal,\n\
and it must have the same effective uid as the debugger.\n\
When using \"attach\" with a process id, the debugger finds the\n\
program running in the process, looking first in the current working\n\
directory, or (if not found there) using the source file search path\n\
(see the \"directory\" command).  You can also use the \"file\" command\n\
to specify the program, and to load its symbol table.");

  add_com ("detach", class_run, detach_command,
	   "Detach a process or file previously attached.\n\
If a process, it is no longer traced, and it continues its execution.  If\n\
you were debugging a file, the file is closed and gdb no longer accesses it.");

  add_com ("signal", class_run, signal_command,
	   "Continue program giving it signal specified by the argument.\n\
An argument of \"0\" means continue program without giving it a signal.");

  add_com ("stepi", class_run, stepi_command,
	   "Step one instruction exactly.\n\
Argument N means do this N times (or till program stops for another reason).");
  add_com_alias ("si", "stepi", class_alias, 0);

  add_com ("nexti", class_run, nexti_command,
	   "Step one instruction, but proceed through subroutine calls.\n\
Argument N means do this N times (or till program stops for another reason).");
  add_com_alias ("ni", "nexti", class_alias, 0);

  add_com ("finish", class_run, finish_command,
	   "Execute until selected stack frame returns.\n\
Upon return, the value returned is printed and put in the value history.");

  add_com ("next", class_run, next_command,
	   "Step program, proceeding through subroutine calls.\n\
Like the \"step\" command as long as subroutine calls do not happen;\n\
when they do, the call is treated as one instruction.\n\
Argument N means do this N times (or till program stops for another reason).");
  add_com_alias ("n", "next", class_run, 1);
  if (xdb_commands)
    add_com_alias ("S", "next", class_run, 1);

  add_com ("step", class_run, step_command,
	   "Step program until it reaches a different source line.\n\
Argument N means do this N times (or till program stops for another reason).");
  add_com_alias ("s", "step", class_run, 1);

  c = add_com ("until", class_run, until_command,
	       "Execute until the program reaches a source line greater than the current\n\
or a specified line or address or function (same args as break command).\n\
Execution will also stop upon exit from the current stack frame.");
  set_cmd_completer (c, location_completer);
  add_com_alias ("u", "until", class_run, 1);

  c = add_com ("jump", class_run, jump_command,
	       "Continue program being debugged at specified line or address.\n\
Give as argument either LINENUM or *ADDR, where ADDR is an expression\n\
for an address to start at.");
  set_cmd_completer (c, location_completer);

  if (xdb_commands)
    {
      c = add_com ("go", class_run, go_command,
		   "Usage: go <location>\n\
Continue program being debugged, stopping at specified line or \n\
address.\n\
Give as argument either LINENUM or *ADDR, where ADDR is an \n\
expression for an address to start at.\n\
This command is a combination of tbreak and jump.");
      set_cmd_completer (c, location_completer);
    }

  if (xdb_commands)
    add_com_alias ("g", "go", class_run, 1);

  add_com ("continue", class_run, continue_command,
	   "Continue program being debugged, after signal or breakpoint.\n\
If proceeding from breakpoint, a number N may be used as an argument,\n\
which means to set the ignore count of that breakpoint to N - 1 (so that\n\
the breakpoint won't break until the Nth time it is reached).");
  add_com_alias ("c", "cont", class_run, 1);
  add_com_alias ("fg", "cont", class_run, 1);

  c = add_com ("run", class_run, run_command,
	   "Start debugged program.  You may specify arguments to give it.\n\
Args may include \"*\", or \"[...]\"; they are expanded using \"sh\".\n\
Input and output redirection with \">\", \"<\", or \">>\" are also allowed.\n\n\
With no arguments, uses arguments last specified (with \"run\" or \"set args\").\n\
To cancel previous arguments and run with no arguments,\n\
use \"set args\" without arguments.");
  set_cmd_completer (c, filename_completer);
  add_com_alias ("r", "run", class_run, 1);
  if (xdb_commands)
    add_com ("R", class_run, run_no_args_command,
	     "Start debugged program with no arguments.");

  add_com ("interrupt", class_run, interrupt_target_command,
	   "Interrupt the execution of the debugged program.");

  add_info ("registers", nofp_registers_info,
	    "List of integer registers and their contents, for selected stack frame.\n\
Register name as argument means describe only that register.");
  add_info_alias ("r", "registers", 1);

  if (xdb_commands)
    add_com ("lr", class_info, nofp_registers_info,
	     "List of integer registers and their contents, for selected stack frame.\n\
  Register name as argument means describe only that register.");
  add_info ("all-registers", all_registers_info,
	    "List of all registers and their contents, for selected stack frame.\n\
Register name as argument means describe only that register.");

  add_info ("program", program_info,
	    "Execution status of the program.");

  add_info ("float", float_info,
	    "Print the status of the floating point unit\n");

  inferior_environ = make_environ ();
  init_environ (inferior_environ);
}