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[/] [or1k/] [trunk/] [insight/] [gdb/] [infrun.c] - Blame information for rev 578

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1 578 markom
/* Target-struct-independent code to start (run) and stop an inferior process.
2
   Copyright 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995,
3
   1996, 1997, 1998, 1999, 2000, 2001 Free Software Foundation, Inc.
4
 
5
   This file is part of GDB.
6
 
7
   This program is free software; you can redistribute it and/or modify
8
   it under the terms of the GNU General Public License as published by
9
   the Free Software Foundation; either version 2 of the License, or
10
   (at your option) any later version.
11
 
12
   This program is distributed in the hope that it will be useful,
13
   but WITHOUT ANY WARRANTY; without even the implied warranty of
14
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15
   GNU General Public License for more details.
16
 
17
   You should have received a copy of the GNU General Public License
18
   along with this program; if not, write to the Free Software
19
   Foundation, Inc., 59 Temple Place - Suite 330,
20
   Boston, MA 02111-1307, USA.  */
21
 
22
#include "defs.h"
23
#include "gdb_string.h"
24
#include <ctype.h>
25
#include "symtab.h"
26
#include "frame.h"
27
#include "inferior.h"
28
#include "breakpoint.h"
29
#include "gdb_wait.h"
30
#include "gdbcore.h"
31
#include "gdbcmd.h"
32
#include "target.h"
33
#include "gdbthread.h"
34
#include "annotate.h"
35
#include "symfile.h"
36
#include "top.h"
37
#include <signal.h>
38
#include "inf-loop.h"
39
#include "regcache.h"
40
 
41
/* Prototypes for local functions */
42
 
43
static void signals_info (char *, int);
44
 
45
static void handle_command (char *, int);
46
 
47
static void sig_print_info (enum target_signal);
48
 
49
static void sig_print_header (void);
50
 
51
static void resume_cleanups (void *);
52
 
53
static int hook_stop_stub (void *);
54
 
55
static void delete_breakpoint_current_contents (void *);
56
 
57
static void set_follow_fork_mode_command (char *arg, int from_tty,
58
                                          struct cmd_list_element * c);
59
 
60
static struct inferior_status *xmalloc_inferior_status (void);
61
 
62
static void free_inferior_status (struct inferior_status *);
63
 
64
static int restore_selected_frame (void *);
65
 
66
static void build_infrun (void);
67
 
68
static void follow_inferior_fork (int parent_pid, int child_pid,
69
                                  int has_forked, int has_vforked);
70
 
71
static void follow_fork (int parent_pid, int child_pid);
72
 
73
static void follow_vfork (int parent_pid, int child_pid);
74
 
75
static void set_schedlock_func (char *args, int from_tty,
76
                                struct cmd_list_element * c);
77
 
78
struct execution_control_state;
79
 
80
static int currently_stepping (struct execution_control_state *ecs);
81
 
82
static void xdb_handle_command (char *args, int from_tty);
83
 
84
void _initialize_infrun (void);
85
 
86
int inferior_ignoring_startup_exec_events = 0;
87
int inferior_ignoring_leading_exec_events = 0;
88
 
89
/* When set, stop the 'step' command if we enter a function which has
90
   no line number information.  The normal behavior is that we step
91
   over such function.  */
92
int step_stop_if_no_debug = 0;
93
 
94
/* In asynchronous mode, but simulating synchronous execution. */
95
 
96
int sync_execution = 0;
97
 
98
/* wait_for_inferior and normal_stop use this to notify the user
99
   when the inferior stopped in a different thread than it had been
100
   running in.  */
101
 
102
static ptid_t previous_inferior_ptid;
103
 
104
/* This is true for configurations that may follow through execl() and
105
   similar functions.  At present this is only true for HP-UX native.  */
106
 
107
#ifndef MAY_FOLLOW_EXEC
108
#define MAY_FOLLOW_EXEC (0)
109
#endif
110
 
111
static int may_follow_exec = MAY_FOLLOW_EXEC;
112
 
113
/* GET_LONGJMP_TARGET returns the PC at which longjmp() will resume the
114
   program.  It needs to examine the jmp_buf argument and extract the PC
115
   from it.  The return value is non-zero on success, zero otherwise. */
116
 
117
#ifndef GET_LONGJMP_TARGET
118
#define GET_LONGJMP_TARGET(PC_ADDR) 0
119
#endif
120
 
121
 
122
/* Some machines have trampoline code that sits between function callers
123
   and the actual functions themselves.  If this machine doesn't have
124
   such things, disable their processing.  */
125
 
126
#ifndef SKIP_TRAMPOLINE_CODE
127
#define SKIP_TRAMPOLINE_CODE(pc)        0
128
#endif
129
 
130
/* Dynamic function trampolines are similar to solib trampolines in that they
131
   are between the caller and the callee.  The difference is that when you
132
   enter a dynamic trampoline, you can't determine the callee's address.  Some
133
   (usually complex) code needs to run in the dynamic trampoline to figure out
134
   the callee's address.  This macro is usually called twice.  First, when we
135
   enter the trampoline (looks like a normal function call at that point).  It
136
   should return the PC of a point within the trampoline where the callee's
137
   address is known.  Second, when we hit the breakpoint, this routine returns
138
   the callee's address.  At that point, things proceed as per a step resume
139
   breakpoint.  */
140
 
141
#ifndef DYNAMIC_TRAMPOLINE_NEXTPC
142
#define DYNAMIC_TRAMPOLINE_NEXTPC(pc) 0
143
#endif
144
 
145
/* If the program uses ELF-style shared libraries, then calls to
146
   functions in shared libraries go through stubs, which live in a
147
   table called the PLT (Procedure Linkage Table).  The first time the
148
   function is called, the stub sends control to the dynamic linker,
149
   which looks up the function's real address, patches the stub so
150
   that future calls will go directly to the function, and then passes
151
   control to the function.
152
 
153
   If we are stepping at the source level, we don't want to see any of
154
   this --- we just want to skip over the stub and the dynamic linker.
155
   The simple approach is to single-step until control leaves the
156
   dynamic linker.
157
 
158
   However, on some systems (e.g., Red Hat Linux 5.2) the dynamic
159
   linker calls functions in the shared C library, so you can't tell
160
   from the PC alone whether the dynamic linker is still running.  In
161
   this case, we use a step-resume breakpoint to get us past the
162
   dynamic linker, as if we were using "next" to step over a function
163
   call.
164
 
165
   IN_SOLIB_DYNSYM_RESOLVE_CODE says whether we're in the dynamic
166
   linker code or not.  Normally, this means we single-step.  However,
167
   if SKIP_SOLIB_RESOLVER then returns non-zero, then its value is an
168
   address where we can place a step-resume breakpoint to get past the
169
   linker's symbol resolution function.
170
 
171
   IN_SOLIB_DYNSYM_RESOLVE_CODE can generally be implemented in a
172
   pretty portable way, by comparing the PC against the address ranges
173
   of the dynamic linker's sections.
174
 
175
   SKIP_SOLIB_RESOLVER is generally going to be system-specific, since
176
   it depends on internal details of the dynamic linker.  It's usually
177
   not too hard to figure out where to put a breakpoint, but it
178
   certainly isn't portable.  SKIP_SOLIB_RESOLVER should do plenty of
179
   sanity checking.  If it can't figure things out, returning zero and
180
   getting the (possibly confusing) stepping behavior is better than
181
   signalling an error, which will obscure the change in the
182
   inferior's state.  */
183
 
184
#ifndef IN_SOLIB_DYNSYM_RESOLVE_CODE
185
#define IN_SOLIB_DYNSYM_RESOLVE_CODE(pc) 0
186
#endif
187
 
188
#ifndef SKIP_SOLIB_RESOLVER
189
#define SKIP_SOLIB_RESOLVER(pc) 0
190
#endif
191
 
192
/* For SVR4 shared libraries, each call goes through a small piece of
193
   trampoline code in the ".plt" section.  IN_SOLIB_CALL_TRAMPOLINE evaluates
194
   to nonzero if we are current stopped in one of these. */
195
 
196
#ifndef IN_SOLIB_CALL_TRAMPOLINE
197
#define IN_SOLIB_CALL_TRAMPOLINE(pc,name)       0
198
#endif
199
 
200
/* In some shared library schemes, the return path from a shared library
201
   call may need to go through a trampoline too.  */
202
 
203
#ifndef IN_SOLIB_RETURN_TRAMPOLINE
204
#define IN_SOLIB_RETURN_TRAMPOLINE(pc,name)     0
205
#endif
206
 
207
/* This function returns TRUE if pc is the address of an instruction
208
   that lies within the dynamic linker (such as the event hook, or the
209
   dld itself).
210
 
211
   This function must be used only when a dynamic linker event has
212
   been caught, and the inferior is being stepped out of the hook, or
213
   undefined results are guaranteed.  */
214
 
215
#ifndef SOLIB_IN_DYNAMIC_LINKER
216
#define SOLIB_IN_DYNAMIC_LINKER(pid,pc) 0
217
#endif
218
 
219
/* On MIPS16, a function that returns a floating point value may call
220
   a library helper function to copy the return value to a floating point
221
   register.  The IGNORE_HELPER_CALL macro returns non-zero if we
222
   should ignore (i.e. step over) this function call.  */
223
#ifndef IGNORE_HELPER_CALL
224
#define IGNORE_HELPER_CALL(pc)  0
225
#endif
226
 
227
/* On some systems, the PC may be left pointing at an instruction that  won't
228
   actually be executed.  This is usually indicated by a bit in the PSW.  If
229
   we find ourselves in such a state, then we step the target beyond the
230
   nullified instruction before returning control to the user so as to avoid
231
   confusion. */
232
 
233
#ifndef INSTRUCTION_NULLIFIED
234
#define INSTRUCTION_NULLIFIED 0
235
#endif
236
 
237
/* We can't step off a permanent breakpoint in the ordinary way, because we
238
   can't remove it.  Instead, we have to advance the PC to the next
239
   instruction.  This macro should expand to a pointer to a function that
240
   does that, or zero if we have no such function.  If we don't have a
241
   definition for it, we have to report an error.  */
242
#ifndef SKIP_PERMANENT_BREAKPOINT 
243
#define SKIP_PERMANENT_BREAKPOINT (default_skip_permanent_breakpoint)
244
static void
245
default_skip_permanent_breakpoint (void)
246
{
247
  error_begin ();
248
  fprintf_filtered (gdb_stderr, "\
249
The program is stopped at a permanent breakpoint, but GDB does not know\n\
250
how to step past a permanent breakpoint on this architecture.  Try using\n\
251
a command like `return' or `jump' to continue execution.\n");
252
  return_to_top_level (RETURN_ERROR);
253
}
254
#endif
255
 
256
 
257
/* Convert the #defines into values.  This is temporary until wfi control
258
   flow is completely sorted out.  */
259
 
260
#ifndef HAVE_STEPPABLE_WATCHPOINT
261
#define HAVE_STEPPABLE_WATCHPOINT 0
262
#else
263
#undef  HAVE_STEPPABLE_WATCHPOINT
264
#define HAVE_STEPPABLE_WATCHPOINT 1
265
#endif
266
 
267
#ifndef HAVE_NONSTEPPABLE_WATCHPOINT
268
#define HAVE_NONSTEPPABLE_WATCHPOINT 0
269
#else
270
#undef  HAVE_NONSTEPPABLE_WATCHPOINT
271
#define HAVE_NONSTEPPABLE_WATCHPOINT 1
272
#endif
273
 
274
#ifndef HAVE_CONTINUABLE_WATCHPOINT
275
#define HAVE_CONTINUABLE_WATCHPOINT 0
276
#else
277
#undef  HAVE_CONTINUABLE_WATCHPOINT
278
#define HAVE_CONTINUABLE_WATCHPOINT 1
279
#endif
280
 
281
#ifndef CANNOT_STEP_HW_WATCHPOINTS
282
#define CANNOT_STEP_HW_WATCHPOINTS 0
283
#else
284
#undef  CANNOT_STEP_HW_WATCHPOINTS
285
#define CANNOT_STEP_HW_WATCHPOINTS 1
286
#endif
287
 
288
/* Tables of how to react to signals; the user sets them.  */
289
 
290
static unsigned char *signal_stop;
291
static unsigned char *signal_print;
292
static unsigned char *signal_program;
293
 
294
#define SET_SIGS(nsigs,sigs,flags) \
295
  do { \
296
    int signum = (nsigs); \
297
    while (signum-- > 0) \
298
      if ((sigs)[signum]) \
299
        (flags)[signum] = 1; \
300
  } while (0)
301
 
302
#define UNSET_SIGS(nsigs,sigs,flags) \
303
  do { \
304
    int signum = (nsigs); \
305
    while (signum-- > 0) \
306
      if ((sigs)[signum]) \
307
        (flags)[signum] = 0; \
308
  } while (0)
309
 
310
/* Value to pass to target_resume() to cause all threads to resume */
311
 
312
#define RESUME_ALL (pid_to_ptid (-1))
313
 
314
/* Command list pointer for the "stop" placeholder.  */
315
 
316
static struct cmd_list_element *stop_command;
317
 
318
/* Nonzero if breakpoints are now inserted in the inferior.  */
319
 
320
static int breakpoints_inserted;
321
 
322
/* Function inferior was in as of last step command.  */
323
 
324
static struct symbol *step_start_function;
325
 
326
/* Nonzero if we are expecting a trace trap and should proceed from it.  */
327
 
328
static int trap_expected;
329
 
330
#ifdef SOLIB_ADD
331
/* Nonzero if we want to give control to the user when we're notified
332
   of shared library events by the dynamic linker.  */
333
static int stop_on_solib_events;
334
#endif
335
 
336
#ifdef HP_OS_BUG
337
/* Nonzero if the next time we try to continue the inferior, it will
338
   step one instruction and generate a spurious trace trap.
339
   This is used to compensate for a bug in HP-UX.  */
340
 
341
static int trap_expected_after_continue;
342
#endif
343
 
344
/* Nonzero means expecting a trace trap
345
   and should stop the inferior and return silently when it happens.  */
346
 
347
int stop_after_trap;
348
 
349
/* Nonzero means expecting a trap and caller will handle it themselves.
350
   It is used after attach, due to attaching to a process;
351
   when running in the shell before the child program has been exec'd;
352
   and when running some kinds of remote stuff (FIXME?).  */
353
 
354
int stop_soon_quietly;
355
 
356
/* Nonzero if proceed is being used for a "finish" command or a similar
357
   situation when stop_registers should be saved.  */
358
 
359
int proceed_to_finish;
360
 
361
/* Save register contents here when about to pop a stack dummy frame,
362
   if-and-only-if proceed_to_finish is set.
363
   Thus this contains the return value from the called function (assuming
364
   values are returned in a register).  */
365
 
366
char *stop_registers;
367
 
368
/* Nonzero if program stopped due to error trying to insert breakpoints.  */
369
 
370
static int breakpoints_failed;
371
 
372
/* Nonzero after stop if current stack frame should be printed.  */
373
 
374
static int stop_print_frame;
375
 
376
static struct breakpoint *step_resume_breakpoint = NULL;
377
static struct breakpoint *through_sigtramp_breakpoint = NULL;
378
 
379
/* On some platforms (e.g., HP-UX), hardware watchpoints have bad
380
   interactions with an inferior that is running a kernel function
381
   (aka, a system call or "syscall").  wait_for_inferior therefore
382
   may have a need to know when the inferior is in a syscall.  This
383
   is a count of the number of inferior threads which are known to
384
   currently be running in a syscall. */
385
static int number_of_threads_in_syscalls;
386
 
387
/* This is a cached copy of the pid/waitstatus of the last event
388
   returned by target_wait()/target_wait_hook().  This information is
389
   returned by get_last_target_status(). */
390
static ptid_t target_last_wait_ptid;
391
static struct target_waitstatus target_last_waitstatus;
392
 
393
/* This is used to remember when a fork, vfork or exec event
394
   was caught by a catchpoint, and thus the event is to be
395
   followed at the next resume of the inferior, and not
396
   immediately. */
397
static struct
398
  {
399
    enum target_waitkind kind;
400
    struct
401
      {
402
        int parent_pid;
403
        int saw_parent_fork;
404
        int child_pid;
405
        int saw_child_fork;
406
        int saw_child_exec;
407
      }
408
    fork_event;
409
    char *execd_pathname;
410
  }
411
pending_follow;
412
 
413
/* Some platforms don't allow us to do anything meaningful with a
414
   vforked child until it has exec'd.  Vforked processes on such
415
   platforms can only be followed after they've exec'd.
416
 
417
   When this is set to 0, a vfork can be immediately followed,
418
   and an exec can be followed merely as an exec.  When this is
419
   set to 1, a vfork event has been seen, but cannot be followed
420
   until the exec is seen.
421
 
422
   (In the latter case, inferior_ptid is still the parent of the
423
   vfork, and pending_follow.fork_event.child_pid is the child.  The
424
   appropriate process is followed, according to the setting of
425
   follow-fork-mode.) */
426
static int follow_vfork_when_exec;
427
 
428
static const char follow_fork_mode_ask[] = "ask";
429
static const char follow_fork_mode_both[] = "both";
430
static const char follow_fork_mode_child[] = "child";
431
static const char follow_fork_mode_parent[] = "parent";
432
 
433
static const char *follow_fork_mode_kind_names[] =
434
{
435
  follow_fork_mode_ask,
436
  /* ??rehrauer: The "both" option is broken, by what may be a 10.20
437
     kernel problem.  It's also not terribly useful without a GUI to
438
     help the user drive two debuggers.  So for now, I'm disabling the
439
     "both" option. */
440
  /* follow_fork_mode_both, */
441
  follow_fork_mode_child,
442
  follow_fork_mode_parent,
443
  NULL
444
};
445
 
446
static const char *follow_fork_mode_string = follow_fork_mode_parent;
447
 
448
 
449
static void
450
follow_inferior_fork (int parent_pid, int child_pid, int has_forked,
451
                      int has_vforked)
452
{
453
  int followed_parent = 0;
454
  int followed_child = 0;
455
 
456
  /* Which process did the user want us to follow? */
457
  const char *follow_mode = follow_fork_mode_string;
458
 
459
  /* Or, did the user not know, and want us to ask? */
460
  if (follow_fork_mode_string == follow_fork_mode_ask)
461
    {
462
      internal_error (__FILE__, __LINE__,
463
                      "follow_inferior_fork: \"ask\" mode not implemented");
464
      /* follow_mode = follow_fork_mode_...; */
465
    }
466
 
467
  /* If we're to be following the parent, then detach from child_pid.
468
     We're already following the parent, so need do nothing explicit
469
     for it. */
470
  if (follow_mode == follow_fork_mode_parent)
471
    {
472
      followed_parent = 1;
473
 
474
      /* We're already attached to the parent, by default. */
475
 
476
      /* Before detaching from the child, remove all breakpoints from
477
         it.  (This won't actually modify the breakpoint list, but will
478
         physically remove the breakpoints from the child.) */
479
      if (!has_vforked || !follow_vfork_when_exec)
480
        {
481
          detach_breakpoints (child_pid);
482
#ifdef SOLIB_REMOVE_INFERIOR_HOOK
483
          SOLIB_REMOVE_INFERIOR_HOOK (child_pid);
484
#endif
485
        }
486
 
487
      /* Detach from the child. */
488
      dont_repeat ();
489
 
490
      target_require_detach (child_pid, "", 1);
491
    }
492
 
493
  /* If we're to be following the child, then attach to it, detach
494
     from inferior_ptid, and set inferior_ptid to child_pid. */
495
  else if (follow_mode == follow_fork_mode_child)
496
    {
497
      char child_pid_spelling[100];     /* Arbitrary length. */
498
 
499
      followed_child = 1;
500
 
501
      /* Before detaching from the parent, detach all breakpoints from
502
         the child.  But only if we're forking, or if we follow vforks
503
         as soon as they happen.  (If we're following vforks only when
504
         the child has exec'd, then it's very wrong to try to write
505
         back the "shadow contents" of inserted breakpoints now -- they
506
         belong to the child's pre-exec'd a.out.) */
507
      if (!has_vforked || !follow_vfork_when_exec)
508
        {
509
          detach_breakpoints (child_pid);
510
        }
511
 
512
      /* Before detaching from the parent, remove all breakpoints from it. */
513
      remove_breakpoints ();
514
 
515
      /* Also reset the solib inferior hook from the parent. */
516
#ifdef SOLIB_REMOVE_INFERIOR_HOOK
517
      SOLIB_REMOVE_INFERIOR_HOOK (PIDGET (inferior_ptid));
518
#endif
519
 
520
      /* Detach from the parent. */
521
      dont_repeat ();
522
      target_detach (NULL, 1);
523
 
524
      /* Attach to the child. */
525
      inferior_ptid = pid_to_ptid (child_pid);
526
      sprintf (child_pid_spelling, "%d", child_pid);
527
      dont_repeat ();
528
 
529
      target_require_attach (child_pid_spelling, 1);
530
 
531
      /* Was there a step_resume breakpoint?  (There was if the user
532
         did a "next" at the fork() call.)  If so, explicitly reset its
533
         thread number.
534
 
535
         step_resumes are a form of bp that are made to be per-thread.
536
         Since we created the step_resume bp when the parent process
537
         was being debugged, and now are switching to the child process,
538
         from the breakpoint package's viewpoint, that's a switch of
539
         "threads".  We must update the bp's notion of which thread
540
         it is for, or it'll be ignored when it triggers... */
541
      if (step_resume_breakpoint &&
542
          (!has_vforked || !follow_vfork_when_exec))
543
        breakpoint_re_set_thread (step_resume_breakpoint);
544
 
545
      /* Reinsert all breakpoints in the child.  (The user may've set
546
         breakpoints after catching the fork, in which case those
547
         actually didn't get set in the child, but only in the parent.) */
548
      if (!has_vforked || !follow_vfork_when_exec)
549
        {
550
          breakpoint_re_set ();
551
          insert_breakpoints ();
552
        }
553
    }
554
 
555
  /* If we're to be following both parent and child, then fork ourselves,
556
     and attach the debugger clone to the child. */
557
  else if (follow_mode == follow_fork_mode_both)
558
    {
559
      char pid_suffix[100];     /* Arbitrary length. */
560
 
561
      /* Clone ourselves to follow the child.  This is the end of our
562
         involvement with child_pid; our clone will take it from here... */
563
      dont_repeat ();
564
      target_clone_and_follow_inferior (child_pid, &followed_child);
565
      followed_parent = !followed_child;
566
 
567
      /* We continue to follow the parent.  To help distinguish the two
568
         debuggers, though, both we and our clone will reset our prompts. */
569
      sprintf (pid_suffix, "[%d] ", PIDGET (inferior_ptid));
570
      set_prompt (strcat (get_prompt (), pid_suffix));
571
    }
572
 
573
  /* The parent and child of a vfork share the same address space.
574
     Also, on some targets the order in which vfork and exec events
575
     are received for parent in child requires some delicate handling
576
     of the events.
577
 
578
     For instance, on ptrace-based HPUX we receive the child's vfork
579
     event first, at which time the parent has been suspended by the
580
     OS and is essentially untouchable until the child's exit or second
581
     exec event arrives.  At that time, the parent's vfork event is
582
     delivered to us, and that's when we see and decide how to follow
583
     the vfork.  But to get to that point, we must continue the child
584
     until it execs or exits.  To do that smoothly, all breakpoints
585
     must be removed from the child, in case there are any set between
586
     the vfork() and exec() calls.  But removing them from the child
587
     also removes them from the parent, due to the shared-address-space
588
     nature of a vfork'd parent and child.  On HPUX, therefore, we must
589
     take care to restore the bp's to the parent before we continue it.
590
     Else, it's likely that we may not stop in the expected place.  (The
591
     worst scenario is when the user tries to step over a vfork() call;
592
     the step-resume bp must be restored for the step to properly stop
593
     in the parent after the call completes!)
594
 
595
     Sequence of events, as reported to gdb from HPUX:
596
 
597
     Parent        Child           Action for gdb to take
598
     -------------------------------------------------------
599
     1                VFORK               Continue child
600
     2                EXEC
601
     3                EXEC or EXIT
602
     4  VFORK */
603
  if (has_vforked)
604
    {
605
      target_post_follow_vfork (parent_pid,
606
                                followed_parent,
607
                                child_pid,
608
                                followed_child);
609
    }
610
 
611
  pending_follow.fork_event.saw_parent_fork = 0;
612
  pending_follow.fork_event.saw_child_fork = 0;
613
}
614
 
615
static void
616
follow_fork (int parent_pid, int child_pid)
617
{
618
  follow_inferior_fork (parent_pid, child_pid, 1, 0);
619
}
620
 
621
 
622
/* Forward declaration. */
623
static void follow_exec (int, char *);
624
 
625
static void
626
follow_vfork (int parent_pid, int child_pid)
627
{
628
  follow_inferior_fork (parent_pid, child_pid, 0, 1);
629
 
630
  /* Did we follow the child?  Had it exec'd before we saw the parent vfork? */
631
  if (pending_follow.fork_event.saw_child_exec
632
      && (PIDGET (inferior_ptid) == child_pid))
633
    {
634
      pending_follow.fork_event.saw_child_exec = 0;
635
      pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
636
      follow_exec (PIDGET (inferior_ptid), pending_follow.execd_pathname);
637
      xfree (pending_follow.execd_pathname);
638
    }
639
}
640
 
641
/* EXECD_PATHNAME is assumed to be non-NULL. */
642
 
643
static void
644
follow_exec (int pid, char *execd_pathname)
645
{
646
  int saved_pid = pid;
647
  struct target_ops *tgt;
648
 
649
  if (!may_follow_exec)
650
    return;
651
 
652
  /* Did this exec() follow a vfork()?  If so, we must follow the
653
     vfork now too.  Do it before following the exec. */
654
  if (follow_vfork_when_exec &&
655
      (pending_follow.kind == TARGET_WAITKIND_VFORKED))
656
    {
657
      pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
658
      follow_vfork (PIDGET (inferior_ptid),
659
                    pending_follow.fork_event.child_pid);
660
      follow_vfork_when_exec = 0;
661
      saved_pid = PIDGET (inferior_ptid);
662
 
663
      /* Did we follow the parent?  If so, we're done.  If we followed
664
         the child then we must also follow its exec(). */
665
      if (PIDGET (inferior_ptid) == pending_follow.fork_event.parent_pid)
666
        return;
667
    }
668
 
669
  /* This is an exec event that we actually wish to pay attention to.
670
     Refresh our symbol table to the newly exec'd program, remove any
671
     momentary bp's, etc.
672
 
673
     If there are breakpoints, they aren't really inserted now,
674
     since the exec() transformed our inferior into a fresh set
675
     of instructions.
676
 
677
     We want to preserve symbolic breakpoints on the list, since
678
     we have hopes that they can be reset after the new a.out's
679
     symbol table is read.
680
 
681
     However, any "raw" breakpoints must be removed from the list
682
     (e.g., the solib bp's), since their address is probably invalid
683
     now.
684
 
685
     And, we DON'T want to call delete_breakpoints() here, since
686
     that may write the bp's "shadow contents" (the instruction
687
     value that was overwritten witha TRAP instruction).  Since
688
     we now have a new a.out, those shadow contents aren't valid. */
689
  update_breakpoints_after_exec ();
690
 
691
  /* If there was one, it's gone now.  We cannot truly step-to-next
692
     statement through an exec(). */
693
  step_resume_breakpoint = NULL;
694
  step_range_start = 0;
695
  step_range_end = 0;
696
 
697
  /* If there was one, it's gone now. */
698
  through_sigtramp_breakpoint = NULL;
699
 
700
  /* What is this a.out's name? */
701
  printf_unfiltered ("Executing new program: %s\n", execd_pathname);
702
 
703
  /* We've followed the inferior through an exec.  Therefore, the
704
     inferior has essentially been killed & reborn. */
705
 
706
  /* First collect the run target in effect.  */
707
  tgt = find_run_target ();
708
  /* If we can't find one, things are in a very strange state...  */
709
  if (tgt == NULL)
710
    error ("Could find run target to save before following exec");
711
 
712
  gdb_flush (gdb_stdout);
713
  target_mourn_inferior ();
714
  inferior_ptid = pid_to_ptid (saved_pid);
715
                        /* Because mourn_inferior resets inferior_ptid. */
716
  push_target (tgt);
717
 
718
  /* That a.out is now the one to use. */
719
  exec_file_attach (execd_pathname, 0);
720
 
721
  /* And also is where symbols can be found. */
722
  symbol_file_add_main (execd_pathname, 0);
723
 
724
  /* Reset the shared library package.  This ensures that we get
725
     a shlib event when the child reaches "_start", at which point
726
     the dld will have had a chance to initialize the child. */
727
#if defined(SOLIB_RESTART)
728
  SOLIB_RESTART ();
729
#endif
730
#ifdef SOLIB_CREATE_INFERIOR_HOOK
731
  SOLIB_CREATE_INFERIOR_HOOK (PIDGET (inferior_ptid));
732
#endif
733
 
734
  /* Reinsert all breakpoints.  (Those which were symbolic have
735
     been reset to the proper address in the new a.out, thanks
736
     to symbol_file_command...) */
737
  insert_breakpoints ();
738
 
739
  /* The next resume of this inferior should bring it to the shlib
740
     startup breakpoints.  (If the user had also set bp's on
741
     "main" from the old (parent) process, then they'll auto-
742
     matically get reset there in the new process.) */
743
}
744
 
745
/* Non-zero if we just simulating a single-step.  This is needed
746
   because we cannot remove the breakpoints in the inferior process
747
   until after the `wait' in `wait_for_inferior'.  */
748
static int singlestep_breakpoints_inserted_p = 0;
749
 
750
 
751
/* Things to clean up if we QUIT out of resume ().  */
752
/* ARGSUSED */
753
static void
754
resume_cleanups (void *ignore)
755
{
756
  normal_stop ();
757
}
758
 
759
static const char schedlock_off[] = "off";
760
static const char schedlock_on[] = "on";
761
static const char schedlock_step[] = "step";
762
static const char *scheduler_mode = schedlock_off;
763
static const char *scheduler_enums[] =
764
{
765
  schedlock_off,
766
  schedlock_on,
767
  schedlock_step,
768
  NULL
769
};
770
 
771
static void
772
set_schedlock_func (char *args, int from_tty, struct cmd_list_element *c)
773
{
774
  if (c->type == set_cmd)
775
    if (!target_can_lock_scheduler)
776
      {
777
        scheduler_mode = schedlock_off;
778
        error ("Target '%s' cannot support this command.",
779
               target_shortname);
780
      }
781
}
782
 
783
 
784
/* Resume the inferior, but allow a QUIT.  This is useful if the user
785
   wants to interrupt some lengthy single-stepping operation
786
   (for child processes, the SIGINT goes to the inferior, and so
787
   we get a SIGINT random_signal, but for remote debugging and perhaps
788
   other targets, that's not true).
789
 
790
   STEP nonzero if we should step (zero to continue instead).
791
   SIG is the signal to give the inferior (zero for none).  */
792
void
793
resume (int step, enum target_signal sig)
794
{
795
  int should_resume = 1;
796
  struct cleanup *old_cleanups = make_cleanup (resume_cleanups, 0);
797
  QUIT;
798
 
799
  /* FIXME: calling breakpoint_here_p (read_pc ()) three times! */
800
 
801
 
802
  /* Some targets (e.g. Solaris x86) have a kernel bug when stepping
803
     over an instruction that causes a page fault without triggering
804
     a hardware watchpoint. The kernel properly notices that it shouldn't
805
     stop, because the hardware watchpoint is not triggered, but it forgets
806
     the step request and continues the program normally.
807
     Work around the problem by removing hardware watchpoints if a step is
808
     requested, GDB will check for a hardware watchpoint trigger after the
809
     step anyway.  */
810
  if (CANNOT_STEP_HW_WATCHPOINTS && step && breakpoints_inserted)
811
    remove_hw_watchpoints ();
812
 
813
 
814
  /* Normally, by the time we reach `resume', the breakpoints are either
815
     removed or inserted, as appropriate.  The exception is if we're sitting
816
     at a permanent breakpoint; we need to step over it, but permanent
817
     breakpoints can't be removed.  So we have to test for it here.  */
818
  if (breakpoint_here_p (read_pc ()) == permanent_breakpoint_here)
819
    SKIP_PERMANENT_BREAKPOINT ();
820
 
821
  if (SOFTWARE_SINGLE_STEP_P () && step)
822
    {
823
      /* Do it the hard way, w/temp breakpoints */
824
      SOFTWARE_SINGLE_STEP (sig, 1 /*insert-breakpoints */ );
825
      /* ...and don't ask hardware to do it.  */
826
      step = 0;
827
      /* and do not pull these breakpoints until after a `wait' in
828
         `wait_for_inferior' */
829
      singlestep_breakpoints_inserted_p = 1;
830
    }
831
 
832
  /* Handle any optimized stores to the inferior NOW...  */
833
#ifdef DO_DEFERRED_STORES
834
  DO_DEFERRED_STORES;
835
#endif
836
 
837
  /* If there were any forks/vforks/execs that were caught and are
838
     now to be followed, then do so. */
839
  switch (pending_follow.kind)
840
    {
841
    case (TARGET_WAITKIND_FORKED):
842
      pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
843
      follow_fork (PIDGET (inferior_ptid),
844
                   pending_follow.fork_event.child_pid);
845
      break;
846
 
847
    case (TARGET_WAITKIND_VFORKED):
848
      {
849
        int saw_child_exec = pending_follow.fork_event.saw_child_exec;
850
 
851
        pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
852
        follow_vfork (PIDGET (inferior_ptid),
853
                      pending_follow.fork_event.child_pid);
854
 
855
        /* Did we follow the child, but not yet see the child's exec event?
856
           If so, then it actually ought to be waiting for us; we respond to
857
           parent vfork events.  We don't actually want to resume the child
858
           in this situation; we want to just get its exec event. */
859
        if (!saw_child_exec &&
860
            (PIDGET (inferior_ptid) == pending_follow.fork_event.child_pid))
861
          should_resume = 0;
862
      }
863
      break;
864
 
865
    case (TARGET_WAITKIND_EXECD):
866
      /* If we saw a vfork event but couldn't follow it until we saw
867
         an exec, then now might be the time! */
868
      pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
869
      /* follow_exec is called as soon as the exec event is seen. */
870
      break;
871
 
872
    default:
873
      break;
874
    }
875
 
876
  /* Install inferior's terminal modes.  */
877
  target_terminal_inferior ();
878
 
879
  if (should_resume)
880
    {
881
      ptid_t resume_ptid;
882
 
883
      resume_ptid = RESUME_ALL;         /* Default */
884
 
885
      if ((step || singlestep_breakpoints_inserted_p) &&
886
          !breakpoints_inserted && breakpoint_here_p (read_pc ()))
887
        {
888
          /* Stepping past a breakpoint without inserting breakpoints.
889
             Make sure only the current thread gets to step, so that
890
             other threads don't sneak past breakpoints while they are
891
             not inserted. */
892
 
893
          resume_ptid = inferior_ptid;
894
        }
895
 
896
      if ((scheduler_mode == schedlock_on) ||
897
          (scheduler_mode == schedlock_step &&
898
           (step || singlestep_breakpoints_inserted_p)))
899
        {
900
          /* User-settable 'scheduler' mode requires solo thread resume. */
901
            resume_ptid = inferior_ptid;
902
        }
903
 
904
#ifdef CANNOT_STEP_BREAKPOINT
905
      /* Most targets can step a breakpoint instruction, thus executing it
906
         normally.  But if this one cannot, just continue and we will hit
907
         it anyway.  */
908
      if (step && breakpoints_inserted && breakpoint_here_p (read_pc ()))
909
        step = 0;
910
#endif
911
      target_resume (resume_ptid, step, sig);
912
    }
913
 
914
  discard_cleanups (old_cleanups);
915
}
916
 
917
 
918
/* Clear out all variables saying what to do when inferior is continued.
919
   First do this, then set the ones you want, then call `proceed'.  */
920
 
921
void
922
clear_proceed_status (void)
923
{
924
  trap_expected = 0;
925
  step_range_start = 0;
926
  step_range_end = 0;
927
  step_frame_address = 0;
928
  step_over_calls = STEP_OVER_UNDEBUGGABLE;
929
  stop_after_trap = 0;
930
  stop_soon_quietly = 0;
931
  proceed_to_finish = 0;
932
  breakpoint_proceeded = 1;     /* We're about to proceed... */
933
 
934
  /* Discard any remaining commands or status from previous stop.  */
935
  bpstat_clear (&stop_bpstat);
936
}
937
 
938
/* Basic routine for continuing the program in various fashions.
939
 
940
   ADDR is the address to resume at, or -1 for resume where stopped.
941
   SIGGNAL is the signal to give it, or 0 for none,
942
   or -1 for act according to how it stopped.
943
   STEP is nonzero if should trap after one instruction.
944
   -1 means return after that and print nothing.
945
   You should probably set various step_... variables
946
   before calling here, if you are stepping.
947
 
948
   You should call clear_proceed_status before calling proceed.  */
949
 
950
void
951
proceed (CORE_ADDR addr, enum target_signal siggnal, int step)
952
{
953
  int oneproc = 0;
954
 
955
  if (step > 0)
956
    step_start_function = find_pc_function (read_pc ());
957
  if (step < 0)
958
    stop_after_trap = 1;
959
 
960
  if (addr == (CORE_ADDR) -1)
961
    {
962
      /* If there is a breakpoint at the address we will resume at,
963
         step one instruction before inserting breakpoints
964
         so that we do not stop right away (and report a second
965
         hit at this breakpoint).  */
966
 
967
      if (read_pc () == stop_pc && breakpoint_here_p (read_pc ()))
968
        oneproc = 1;
969
 
970
#ifndef STEP_SKIPS_DELAY
971
#define STEP_SKIPS_DELAY(pc) (0)
972
#define STEP_SKIPS_DELAY_P (0)
973
#endif
974
      /* Check breakpoint_here_p first, because breakpoint_here_p is fast
975
         (it just checks internal GDB data structures) and STEP_SKIPS_DELAY
976
         is slow (it needs to read memory from the target).  */
977
      if (STEP_SKIPS_DELAY_P
978
          && breakpoint_here_p (read_pc () + 4)
979
          && STEP_SKIPS_DELAY (read_pc ()))
980
        oneproc = 1;
981
    }
982
  else
983
    {
984
      write_pc (addr);
985
    }
986
 
987
#ifdef PREPARE_TO_PROCEED
988
  /* In a multi-threaded task we may select another thread
989
     and then continue or step.
990
 
991
     But if the old thread was stopped at a breakpoint, it
992
     will immediately cause another breakpoint stop without
993
     any execution (i.e. it will report a breakpoint hit
994
     incorrectly).  So we must step over it first.
995
 
996
     PREPARE_TO_PROCEED checks the current thread against the thread
997
     that reported the most recent event.  If a step-over is required
998
     it returns TRUE and sets the current thread to the old thread. */
999
  if (PREPARE_TO_PROCEED (1) && breakpoint_here_p (read_pc ()))
1000
    {
1001
      oneproc = 1;
1002
    }
1003
 
1004
#endif /* PREPARE_TO_PROCEED */
1005
 
1006
#ifdef HP_OS_BUG
1007
  if (trap_expected_after_continue)
1008
    {
1009
      /* If (step == 0), a trap will be automatically generated after
1010
         the first instruction is executed.  Force step one
1011
         instruction to clear this condition.  This should not occur
1012
         if step is nonzero, but it is harmless in that case.  */
1013
      oneproc = 1;
1014
      trap_expected_after_continue = 0;
1015
    }
1016
#endif /* HP_OS_BUG */
1017
 
1018
  if (oneproc)
1019
    /* We will get a trace trap after one instruction.
1020
       Continue it automatically and insert breakpoints then.  */
1021
    trap_expected = 1;
1022
  else
1023
    {
1024
      int temp = insert_breakpoints ();
1025
      if (temp)
1026
        {
1027
          print_sys_errmsg ("insert_breakpoints", temp);
1028
          error ("Cannot insert breakpoints.\n\
1029
The same program may be running in another process,\n\
1030
or you may have requested too many hardware\n\
1031
breakpoints and/or watchpoints.\n");
1032
        }
1033
 
1034
      breakpoints_inserted = 1;
1035
    }
1036
 
1037
  if (siggnal != TARGET_SIGNAL_DEFAULT)
1038
    stop_signal = siggnal;
1039
  /* If this signal should not be seen by program,
1040
     give it zero.  Used for debugging signals.  */
1041
  else if (!signal_program[stop_signal])
1042
    stop_signal = TARGET_SIGNAL_0;
1043
 
1044
  annotate_starting ();
1045
 
1046
  /* Make sure that output from GDB appears before output from the
1047
     inferior.  */
1048
  gdb_flush (gdb_stdout);
1049
 
1050
  /* Resume inferior.  */
1051
  resume (oneproc || step || bpstat_should_step (), stop_signal);
1052
 
1053
  /* Wait for it to stop (if not standalone)
1054
     and in any case decode why it stopped, and act accordingly.  */
1055
  /* Do this only if we are not using the event loop, or if the target
1056
     does not support asynchronous execution. */
1057
  if (!event_loop_p || !target_can_async_p ())
1058
    {
1059
      wait_for_inferior ();
1060
      normal_stop ();
1061
    }
1062
}
1063
 
1064
/* Record the pc and sp of the program the last time it stopped.
1065
   These are just used internally by wait_for_inferior, but need
1066
   to be preserved over calls to it and cleared when the inferior
1067
   is started.  */
1068
static CORE_ADDR prev_pc;
1069
static CORE_ADDR prev_func_start;
1070
static char *prev_func_name;
1071
 
1072
 
1073
/* Start remote-debugging of a machine over a serial link.  */
1074
 
1075
void
1076
start_remote (void)
1077
{
1078
  init_thread_list ();
1079
  init_wait_for_inferior ();
1080
  stop_soon_quietly = 1;
1081
  trap_expected = 0;
1082
 
1083
  /* Always go on waiting for the target, regardless of the mode. */
1084
  /* FIXME: cagney/1999-09-23: At present it isn't possible to
1085
     indicate to wait_for_inferior that a target should timeout if
1086
     nothing is returned (instead of just blocking).  Because of this,
1087
     targets expecting an immediate response need to, internally, set
1088
     things up so that the target_wait() is forced to eventually
1089
     timeout. */
1090
  /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
1091
     differentiate to its caller what the state of the target is after
1092
     the initial open has been performed.  Here we're assuming that
1093
     the target has stopped.  It should be possible to eventually have
1094
     target_open() return to the caller an indication that the target
1095
     is currently running and GDB state should be set to the same as
1096
     for an async run. */
1097
  wait_for_inferior ();
1098
  normal_stop ();
1099
}
1100
 
1101
/* Initialize static vars when a new inferior begins.  */
1102
 
1103
void
1104
init_wait_for_inferior (void)
1105
{
1106
  /* These are meaningless until the first time through wait_for_inferior.  */
1107
  prev_pc = 0;
1108
  prev_func_start = 0;
1109
  prev_func_name = NULL;
1110
 
1111
#ifdef HP_OS_BUG
1112
  trap_expected_after_continue = 0;
1113
#endif
1114
  breakpoints_inserted = 0;
1115
  breakpoint_init_inferior (inf_starting);
1116
 
1117
  /* Don't confuse first call to proceed(). */
1118
  stop_signal = TARGET_SIGNAL_0;
1119
 
1120
  /* The first resume is not following a fork/vfork/exec. */
1121
  pending_follow.kind = TARGET_WAITKIND_SPURIOUS;       /* I.e., none. */
1122
  pending_follow.fork_event.saw_parent_fork = 0;
1123
  pending_follow.fork_event.saw_child_fork = 0;
1124
  pending_follow.fork_event.saw_child_exec = 0;
1125
 
1126
  /* See wait_for_inferior's handling of SYSCALL_ENTRY/RETURN events. */
1127
  number_of_threads_in_syscalls = 0;
1128
 
1129
  clear_proceed_status ();
1130
}
1131
 
1132
static void
1133
delete_breakpoint_current_contents (void *arg)
1134
{
1135
  struct breakpoint **breakpointp = (struct breakpoint **) arg;
1136
  if (*breakpointp != NULL)
1137
    {
1138
      delete_breakpoint (*breakpointp);
1139
      *breakpointp = NULL;
1140
    }
1141
}
1142
 
1143
/* This enum encodes possible reasons for doing a target_wait, so that
1144
   wfi can call target_wait in one place.  (Ultimately the call will be
1145
   moved out of the infinite loop entirely.) */
1146
 
1147
enum infwait_states
1148
{
1149
  infwait_normal_state,
1150
  infwait_thread_hop_state,
1151
  infwait_nullified_state,
1152
  infwait_nonstep_watch_state
1153
};
1154
 
1155
/* Why did the inferior stop? Used to print the appropriate messages
1156
   to the interface from within handle_inferior_event(). */
1157
enum inferior_stop_reason
1158
{
1159
  /* We don't know why. */
1160
  STOP_UNKNOWN,
1161
  /* Step, next, nexti, stepi finished. */
1162
  END_STEPPING_RANGE,
1163
  /* Found breakpoint. */
1164
  BREAKPOINT_HIT,
1165
  /* Inferior terminated by signal. */
1166
  SIGNAL_EXITED,
1167
  /* Inferior exited. */
1168
  EXITED,
1169
  /* Inferior received signal, and user asked to be notified. */
1170
  SIGNAL_RECEIVED
1171
};
1172
 
1173
/* This structure contains what used to be local variables in
1174
   wait_for_inferior.  Probably many of them can return to being
1175
   locals in handle_inferior_event.  */
1176
 
1177
struct execution_control_state
1178
  {
1179
    struct target_waitstatus ws;
1180
    struct target_waitstatus *wp;
1181
    int another_trap;
1182
    int random_signal;
1183
    CORE_ADDR stop_func_start;
1184
    CORE_ADDR stop_func_end;
1185
    char *stop_func_name;
1186
    struct symtab_and_line sal;
1187
    int remove_breakpoints_on_following_step;
1188
    int current_line;
1189
    struct symtab *current_symtab;
1190
    int handling_longjmp;       /* FIXME */
1191
    ptid_t ptid;
1192
    ptid_t saved_inferior_ptid;
1193
    int update_step_sp;
1194
    int stepping_through_solib_after_catch;
1195
    bpstat stepping_through_solib_catchpoints;
1196
    int enable_hw_watchpoints_after_wait;
1197
    int stepping_through_sigtramp;
1198
    int new_thread_event;
1199
    struct target_waitstatus tmpstatus;
1200
    enum infwait_states infwait_state;
1201
    ptid_t waiton_ptid;
1202
    int wait_some_more;
1203
  };
1204
 
1205
void init_execution_control_state (struct execution_control_state * ecs);
1206
 
1207
void handle_inferior_event (struct execution_control_state * ecs);
1208
 
1209
static void check_sigtramp2 (struct execution_control_state *ecs);
1210
static void step_into_function (struct execution_control_state *ecs);
1211
static void step_over_function (struct execution_control_state *ecs);
1212
static void stop_stepping (struct execution_control_state *ecs);
1213
static void prepare_to_wait (struct execution_control_state *ecs);
1214
static void keep_going (struct execution_control_state *ecs);
1215
static void print_stop_reason (enum inferior_stop_reason stop_reason, int stop_info);
1216
 
1217
/* Wait for control to return from inferior to debugger.
1218
   If inferior gets a signal, we may decide to start it up again
1219
   instead of returning.  That is why there is a loop in this function.
1220
   When this function actually returns it means the inferior
1221
   should be left stopped and GDB should read more commands.  */
1222
 
1223
void
1224
wait_for_inferior (void)
1225
{
1226
  struct cleanup *old_cleanups;
1227
  struct execution_control_state ecss;
1228
  struct execution_control_state *ecs;
1229
 
1230
  old_cleanups = make_cleanup (delete_step_resume_breakpoint,
1231
                               &step_resume_breakpoint);
1232
  make_cleanup (delete_breakpoint_current_contents,
1233
                &through_sigtramp_breakpoint);
1234
 
1235
  /* wfi still stays in a loop, so it's OK just to take the address of
1236
     a local to get the ecs pointer.  */
1237
  ecs = &ecss;
1238
 
1239
  /* Fill in with reasonable starting values.  */
1240
  init_execution_control_state (ecs);
1241
 
1242
  /* We'll update this if & when we switch to a new thread. */
1243
  previous_inferior_ptid = inferior_ptid;
1244
 
1245
  overlay_cache_invalid = 1;
1246
 
1247
  /* We have to invalidate the registers BEFORE calling target_wait
1248
     because they can be loaded from the target while in target_wait.
1249
     This makes remote debugging a bit more efficient for those
1250
     targets that provide critical registers as part of their normal
1251
     status mechanism. */
1252
 
1253
  registers_changed ();
1254
 
1255
  while (1)
1256
    {
1257
      if (target_wait_hook)
1258
        ecs->ptid = target_wait_hook (ecs->waiton_ptid, ecs->wp);
1259
      else
1260
        ecs->ptid = target_wait (ecs->waiton_ptid, ecs->wp);
1261
 
1262
      /* Now figure out what to do with the result of the result.  */
1263
      handle_inferior_event (ecs);
1264
 
1265
      if (!ecs->wait_some_more)
1266
        break;
1267
    }
1268
  do_cleanups (old_cleanups);
1269
}
1270
 
1271
/* Asynchronous version of wait_for_inferior. It is called by the
1272
   event loop whenever a change of state is detected on the file
1273
   descriptor corresponding to the target. It can be called more than
1274
   once to complete a single execution command. In such cases we need
1275
   to keep the state in a global variable ASYNC_ECSS. If it is the
1276
   last time that this function is called for a single execution
1277
   command, then report to the user that the inferior has stopped, and
1278
   do the necessary cleanups. */
1279
 
1280
struct execution_control_state async_ecss;
1281
struct execution_control_state *async_ecs;
1282
 
1283
void
1284
fetch_inferior_event (void *client_data)
1285
{
1286
  static struct cleanup *old_cleanups;
1287
 
1288
  async_ecs = &async_ecss;
1289
 
1290
  if (!async_ecs->wait_some_more)
1291
    {
1292
      old_cleanups = make_exec_cleanup (delete_step_resume_breakpoint,
1293
                                        &step_resume_breakpoint);
1294
      make_exec_cleanup (delete_breakpoint_current_contents,
1295
                         &through_sigtramp_breakpoint);
1296
 
1297
      /* Fill in with reasonable starting values.  */
1298
      init_execution_control_state (async_ecs);
1299
 
1300
      /* We'll update this if & when we switch to a new thread. */
1301
      previous_inferior_ptid = inferior_ptid;
1302
 
1303
      overlay_cache_invalid = 1;
1304
 
1305
      /* We have to invalidate the registers BEFORE calling target_wait
1306
         because they can be loaded from the target while in target_wait.
1307
         This makes remote debugging a bit more efficient for those
1308
         targets that provide critical registers as part of their normal
1309
         status mechanism. */
1310
 
1311
      registers_changed ();
1312
    }
1313
 
1314
  if (target_wait_hook)
1315
    async_ecs->ptid = target_wait_hook (async_ecs->waiton_ptid, async_ecs->wp);
1316
  else
1317
    async_ecs->ptid = target_wait (async_ecs->waiton_ptid, async_ecs->wp);
1318
 
1319
  /* Now figure out what to do with the result of the result.  */
1320
  handle_inferior_event (async_ecs);
1321
 
1322
  if (!async_ecs->wait_some_more)
1323
    {
1324
      /* Do only the cleanups that have been added by this
1325
         function. Let the continuations for the commands do the rest,
1326
         if there are any. */
1327
      do_exec_cleanups (old_cleanups);
1328
      normal_stop ();
1329
      if (step_multi && stop_step)
1330
        inferior_event_handler (INF_EXEC_CONTINUE, NULL);
1331
      else
1332
        inferior_event_handler (INF_EXEC_COMPLETE, NULL);
1333
    }
1334
}
1335
 
1336
/* Prepare an execution control state for looping through a
1337
   wait_for_inferior-type loop.  */
1338
 
1339
void
1340
init_execution_control_state (struct execution_control_state *ecs)
1341
{
1342
  /* ecs->another_trap? */
1343
  ecs->random_signal = 0;
1344
  ecs->remove_breakpoints_on_following_step = 0;
1345
  ecs->handling_longjmp = 0;     /* FIXME */
1346
  ecs->update_step_sp = 0;
1347
  ecs->stepping_through_solib_after_catch = 0;
1348
  ecs->stepping_through_solib_catchpoints = NULL;
1349
  ecs->enable_hw_watchpoints_after_wait = 0;
1350
  ecs->stepping_through_sigtramp = 0;
1351
  ecs->sal = find_pc_line (prev_pc, 0);
1352
  ecs->current_line = ecs->sal.line;
1353
  ecs->current_symtab = ecs->sal.symtab;
1354
  ecs->infwait_state = infwait_normal_state;
1355
  ecs->waiton_ptid = pid_to_ptid (-1);
1356
  ecs->wp = &(ecs->ws);
1357
}
1358
 
1359
/* Call this function before setting step_resume_breakpoint, as a
1360
   sanity check.  There should never be more than one step-resume
1361
   breakpoint per thread, so we should never be setting a new
1362
   step_resume_breakpoint when one is already active.  */
1363
static void
1364
check_for_old_step_resume_breakpoint (void)
1365
{
1366
  if (step_resume_breakpoint)
1367
    warning ("GDB bug: infrun.c (wait_for_inferior): dropping old step_resume breakpoint");
1368
}
1369
 
1370
/* Return the cached copy of the last pid/waitstatus returned by
1371
   target_wait()/target_wait_hook().  The data is actually cached by
1372
   handle_inferior_event(), which gets called immediately after
1373
   target_wait()/target_wait_hook().  */
1374
 
1375
void
1376
get_last_target_status(ptid_t *ptidp, struct target_waitstatus *status)
1377
{
1378
  *ptidp = target_last_wait_ptid;
1379
  *status = target_last_waitstatus;
1380
}
1381
 
1382
/* Switch thread contexts, maintaining "infrun state". */
1383
 
1384
static void
1385
context_switch (struct execution_control_state *ecs)
1386
{
1387
  /* Caution: it may happen that the new thread (or the old one!)
1388
     is not in the thread list.  In this case we must not attempt
1389
     to "switch context", or we run the risk that our context may
1390
     be lost.  This may happen as a result of the target module
1391
     mishandling thread creation.  */
1392
 
1393
  if (in_thread_list (inferior_ptid) && in_thread_list (ecs->ptid))
1394
    { /* Perform infrun state context switch: */
1395
      /* Save infrun state for the old thread.  */
1396
      save_infrun_state (inferior_ptid, prev_pc,
1397
                         prev_func_start, prev_func_name,
1398
                         trap_expected, step_resume_breakpoint,
1399
                         through_sigtramp_breakpoint, step_range_start,
1400
                         step_range_end, step_frame_address,
1401
                         ecs->handling_longjmp, ecs->another_trap,
1402
                         ecs->stepping_through_solib_after_catch,
1403
                         ecs->stepping_through_solib_catchpoints,
1404
                         ecs->stepping_through_sigtramp,
1405
                         ecs->current_line, ecs->current_symtab,
1406
                         step_sp);
1407
 
1408
      /* Load infrun state for the new thread.  */
1409
      load_infrun_state (ecs->ptid, &prev_pc,
1410
                         &prev_func_start, &prev_func_name,
1411
                         &trap_expected, &step_resume_breakpoint,
1412
                         &through_sigtramp_breakpoint, &step_range_start,
1413
                         &step_range_end, &step_frame_address,
1414
                         &ecs->handling_longjmp, &ecs->another_trap,
1415
                         &ecs->stepping_through_solib_after_catch,
1416
                         &ecs->stepping_through_solib_catchpoints,
1417
                         &ecs->stepping_through_sigtramp,
1418
                         &ecs->current_line, &ecs->current_symtab,
1419
                         &step_sp);
1420
    }
1421
  inferior_ptid = ecs->ptid;
1422
}
1423
 
1424
 
1425
/* Given an execution control state that has been freshly filled in
1426
   by an event from the inferior, figure out what it means and take
1427
   appropriate action.  */
1428
 
1429
void
1430
handle_inferior_event (struct execution_control_state *ecs)
1431
{
1432
  CORE_ADDR tmp;
1433
  int stepped_after_stopped_by_watchpoint;
1434
 
1435
  /* Cache the last pid/waitstatus. */
1436
  target_last_wait_ptid = ecs->ptid;
1437
  target_last_waitstatus = *ecs->wp;
1438
 
1439
  /* Keep this extra brace for now, minimizes diffs.  */
1440
  {
1441
    switch (ecs->infwait_state)
1442
      {
1443
      case infwait_thread_hop_state:
1444
        /* Cancel the waiton_ptid. */
1445
        ecs->waiton_ptid = pid_to_ptid (-1);
1446
        /* Fall thru to the normal_state case. */
1447
 
1448
      case infwait_normal_state:
1449
        /* See comments where a TARGET_WAITKIND_SYSCALL_RETURN event
1450
           is serviced in this loop, below. */
1451
        if (ecs->enable_hw_watchpoints_after_wait)
1452
          {
1453
            TARGET_ENABLE_HW_WATCHPOINTS (PIDGET (inferior_ptid));
1454
            ecs->enable_hw_watchpoints_after_wait = 0;
1455
          }
1456
        stepped_after_stopped_by_watchpoint = 0;
1457
        break;
1458
 
1459
      case infwait_nullified_state:
1460
        break;
1461
 
1462
      case infwait_nonstep_watch_state:
1463
        insert_breakpoints ();
1464
 
1465
        /* FIXME-maybe: is this cleaner than setting a flag?  Does it
1466
           handle things like signals arriving and other things happening
1467
           in combination correctly?  */
1468
        stepped_after_stopped_by_watchpoint = 1;
1469
        break;
1470
      }
1471
    ecs->infwait_state = infwait_normal_state;
1472
 
1473
    flush_cached_frames ();
1474
 
1475
    /* If it's a new process, add it to the thread database */
1476
 
1477
    ecs->new_thread_event = (! ptid_equal (ecs->ptid, inferior_ptid)
1478
                             && ! in_thread_list (ecs->ptid));
1479
 
1480
    if (ecs->ws.kind != TARGET_WAITKIND_EXITED
1481
        && ecs->ws.kind != TARGET_WAITKIND_SIGNALLED
1482
        && ecs->new_thread_event)
1483
      {
1484
        add_thread (ecs->ptid);
1485
 
1486
#ifdef UI_OUT
1487
        ui_out_text (uiout, "[New ");
1488
        ui_out_text (uiout, target_pid_or_tid_to_str (ecs->ptid));
1489
        ui_out_text (uiout, "]\n");
1490
#else
1491
        printf_filtered ("[New %s]\n", target_pid_or_tid_to_str (ecs->ptid));
1492
#endif
1493
 
1494
#if 0
1495
        /* NOTE: This block is ONLY meant to be invoked in case of a
1496
           "thread creation event"!  If it is invoked for any other
1497
           sort of event (such as a new thread landing on a breakpoint),
1498
           the event will be discarded, which is almost certainly
1499
           a bad thing!
1500
 
1501
           To avoid this, the low-level module (eg. target_wait)
1502
           should call in_thread_list and add_thread, so that the
1503
           new thread is known by the time we get here.  */
1504
 
1505
        /* We may want to consider not doing a resume here in order
1506
           to give the user a chance to play with the new thread.
1507
           It might be good to make that a user-settable option.  */
1508
 
1509
        /* At this point, all threads are stopped (happens
1510
           automatically in either the OS or the native code).
1511
           Therefore we need to continue all threads in order to
1512
           make progress.  */
1513
 
1514
        target_resume (RESUME_ALL, 0, TARGET_SIGNAL_0);
1515
        prepare_to_wait (ecs);
1516
        return;
1517
#endif
1518
      }
1519
 
1520
    switch (ecs->ws.kind)
1521
      {
1522
      case TARGET_WAITKIND_LOADED:
1523
        /* Ignore gracefully during startup of the inferior, as it
1524
           might be the shell which has just loaded some objects,
1525
           otherwise add the symbols for the newly loaded objects.  */
1526
#ifdef SOLIB_ADD
1527
        if (!stop_soon_quietly)
1528
          {
1529
            /* Remove breakpoints, SOLIB_ADD might adjust
1530
               breakpoint addresses via breakpoint_re_set.  */
1531
            if (breakpoints_inserted)
1532
              remove_breakpoints ();
1533
 
1534
            /* Check for any newly added shared libraries if we're
1535
               supposed to be adding them automatically.  */
1536
            if (auto_solib_add)
1537
              {
1538
                /* Switch terminal for any messages produced by
1539
                   breakpoint_re_set.  */
1540
                target_terminal_ours_for_output ();
1541
                SOLIB_ADD (NULL, 0, NULL);
1542
                target_terminal_inferior ();
1543
              }
1544
 
1545
            /* Reinsert breakpoints and continue.  */
1546
            if (breakpoints_inserted)
1547
              insert_breakpoints ();
1548
          }
1549
#endif
1550
        resume (0, TARGET_SIGNAL_0);
1551
        prepare_to_wait (ecs);
1552
        return;
1553
 
1554
      case TARGET_WAITKIND_SPURIOUS:
1555
        resume (0, TARGET_SIGNAL_0);
1556
        prepare_to_wait (ecs);
1557
        return;
1558
 
1559
      case TARGET_WAITKIND_EXITED:
1560
        target_terminal_ours ();        /* Must do this before mourn anyway */
1561
        print_stop_reason (EXITED, ecs->ws.value.integer);
1562
 
1563
        /* Record the exit code in the convenience variable $_exitcode, so
1564
           that the user can inspect this again later.  */
1565
        set_internalvar (lookup_internalvar ("_exitcode"),
1566
                         value_from_longest (builtin_type_int,
1567
                                          (LONGEST) ecs->ws.value.integer));
1568
        gdb_flush (gdb_stdout);
1569
        target_mourn_inferior ();
1570
        singlestep_breakpoints_inserted_p = 0;   /*SOFTWARE_SINGLE_STEP_P() */
1571
        stop_print_frame = 0;
1572
        stop_stepping (ecs);
1573
        return;
1574
 
1575
      case TARGET_WAITKIND_SIGNALLED:
1576
        stop_print_frame = 0;
1577
        stop_signal = ecs->ws.value.sig;
1578
        target_terminal_ours ();        /* Must do this before mourn anyway */
1579
 
1580
        /* Note: By definition of TARGET_WAITKIND_SIGNALLED, we shouldn't
1581
           reach here unless the inferior is dead.  However, for years
1582
           target_kill() was called here, which hints that fatal signals aren't
1583
           really fatal on some systems.  If that's true, then some changes
1584
           may be needed. */
1585
        target_mourn_inferior ();
1586
 
1587
        print_stop_reason (SIGNAL_EXITED, stop_signal);
1588
        singlestep_breakpoints_inserted_p = 0;   /*SOFTWARE_SINGLE_STEP_P() */
1589
        stop_stepping (ecs);
1590
        return;
1591
 
1592
        /* The following are the only cases in which we keep going;
1593
           the above cases end in a continue or goto. */
1594
      case TARGET_WAITKIND_FORKED:
1595
        stop_signal = TARGET_SIGNAL_TRAP;
1596
        pending_follow.kind = ecs->ws.kind;
1597
 
1598
        /* Ignore fork events reported for the parent; we're only
1599
           interested in reacting to forks of the child.  Note that
1600
           we expect the child's fork event to be available if we
1601
           waited for it now. */
1602
        if (ptid_equal (inferior_ptid, ecs->ptid))
1603
          {
1604
            pending_follow.fork_event.saw_parent_fork = 1;
1605
            pending_follow.fork_event.parent_pid = PIDGET (ecs->ptid);
1606
            pending_follow.fork_event.child_pid = ecs->ws.value.related_pid;
1607
            prepare_to_wait (ecs);
1608
            return;
1609
          }
1610
        else
1611
          {
1612
            pending_follow.fork_event.saw_child_fork = 1;
1613
            pending_follow.fork_event.child_pid = PIDGET (ecs->ptid);
1614
            pending_follow.fork_event.parent_pid = ecs->ws.value.related_pid;
1615
          }
1616
 
1617
        stop_pc = read_pc_pid (ecs->ptid);
1618
        ecs->saved_inferior_ptid = inferior_ptid;
1619
        inferior_ptid = ecs->ptid;
1620
        /* The second argument of bpstat_stop_status is meant to help
1621
           distinguish between a breakpoint trap and a singlestep trap.
1622
           This is only important on targets where DECR_PC_AFTER_BREAK
1623
           is non-zero.  The prev_pc test is meant to distinguish between
1624
           singlestepping a trap instruction, and singlestepping thru a
1625
           jump to the instruction following a trap instruction. */
1626
 
1627
        stop_bpstat = bpstat_stop_status (&stop_pc,
1628
                                          currently_stepping (ecs) &&
1629
                                          prev_pc !=
1630
                                          stop_pc - DECR_PC_AFTER_BREAK);
1631
        ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
1632
        inferior_ptid = ecs->saved_inferior_ptid;
1633
        goto process_event_stop_test;
1634
 
1635
        /* If this a platform which doesn't allow a debugger to touch a
1636
           vfork'd inferior until after it exec's, then we'd best keep
1637
           our fingers entirely off the inferior, other than continuing
1638
           it.  This has the unfortunate side-effect that catchpoints
1639
           of vforks will be ignored.  But since the platform doesn't
1640
           allow the inferior be touched at vfork time, there's really
1641
           little choice. */
1642
      case TARGET_WAITKIND_VFORKED:
1643
        stop_signal = TARGET_SIGNAL_TRAP;
1644
        pending_follow.kind = ecs->ws.kind;
1645
 
1646
        /* Is this a vfork of the parent?  If so, then give any
1647
           vfork catchpoints a chance to trigger now.  (It's
1648
           dangerous to do so if the child canot be touched until
1649
           it execs, and the child has not yet exec'd.  We probably
1650
           should warn the user to that effect when the catchpoint
1651
           triggers...) */
1652
        if (ptid_equal (ecs->ptid, inferior_ptid))
1653
          {
1654
            pending_follow.fork_event.saw_parent_fork = 1;
1655
            pending_follow.fork_event.parent_pid = PIDGET (ecs->ptid);
1656
            pending_follow.fork_event.child_pid = ecs->ws.value.related_pid;
1657
          }
1658
 
1659
        /* If we've seen the child's vfork event but cannot really touch
1660
           the child until it execs, then we must continue the child now.
1661
           Else, give any vfork catchpoints a chance to trigger now. */
1662
        else
1663
          {
1664
            pending_follow.fork_event.saw_child_fork = 1;
1665
            pending_follow.fork_event.child_pid = PIDGET (ecs->ptid);
1666
            pending_follow.fork_event.parent_pid = ecs->ws.value.related_pid;
1667
            target_post_startup_inferior (
1668
              pid_to_ptid (pending_follow.fork_event.child_pid));
1669
            follow_vfork_when_exec = !target_can_follow_vfork_prior_to_exec ();
1670
            if (follow_vfork_when_exec)
1671
              {
1672
                target_resume (ecs->ptid, 0, TARGET_SIGNAL_0);
1673
                prepare_to_wait (ecs);
1674
                return;
1675
              }
1676
          }
1677
 
1678
        stop_pc = read_pc ();
1679
        /* The second argument of bpstat_stop_status is meant to help
1680
           distinguish between a breakpoint trap and a singlestep trap.
1681
           This is only important on targets where DECR_PC_AFTER_BREAK
1682
           is non-zero.  The prev_pc test is meant to distinguish between
1683
           singlestepping a trap instruction, and singlestepping thru a
1684
           jump to the instruction following a trap instruction. */
1685
 
1686
        stop_bpstat = bpstat_stop_status (&stop_pc,
1687
                                          currently_stepping (ecs) &&
1688
                                          prev_pc !=
1689
                                          stop_pc - DECR_PC_AFTER_BREAK);
1690
        ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
1691
        goto process_event_stop_test;
1692
 
1693
      case TARGET_WAITKIND_EXECD:
1694
        stop_signal = TARGET_SIGNAL_TRAP;
1695
 
1696
        /* Is this a target which reports multiple exec events per actual
1697
           call to exec()?  (HP-UX using ptrace does, for example.)  If so,
1698
           ignore all but the last one.  Just resume the exec'r, and wait
1699
           for the next exec event. */
1700
        if (inferior_ignoring_leading_exec_events)
1701
          {
1702
            inferior_ignoring_leading_exec_events--;
1703
            if (pending_follow.kind == TARGET_WAITKIND_VFORKED)
1704
              ENSURE_VFORKING_PARENT_REMAINS_STOPPED (pending_follow.fork_event.parent_pid);
1705
            target_resume (ecs->ptid, 0, TARGET_SIGNAL_0);
1706
            prepare_to_wait (ecs);
1707
            return;
1708
          }
1709
        inferior_ignoring_leading_exec_events =
1710
          target_reported_exec_events_per_exec_call () - 1;
1711
 
1712
        pending_follow.execd_pathname =
1713
          savestring (ecs->ws.value.execd_pathname,
1714
                      strlen (ecs->ws.value.execd_pathname));
1715
 
1716
        /* Did inferior_ptid exec, or did a (possibly not-yet-followed)
1717
           child of a vfork exec?
1718
 
1719
           ??rehrauer: This is unabashedly an HP-UX specific thing.  On
1720
           HP-UX, events associated with a vforking inferior come in
1721
           threes: a vfork event for the child (always first), followed
1722
           a vfork event for the parent and an exec event for the child.
1723
           The latter two can come in either order.
1724
 
1725
           If we get the parent vfork event first, life's good: We follow
1726
           either the parent or child, and then the child's exec event is
1727
           a "don't care".
1728
 
1729
           But if we get the child's exec event first, then we delay
1730
           responding to it until we handle the parent's vfork.  Because,
1731
           otherwise we can't satisfy a "catch vfork". */
1732
        if (pending_follow.kind == TARGET_WAITKIND_VFORKED)
1733
          {
1734
            pending_follow.fork_event.saw_child_exec = 1;
1735
 
1736
            /* On some targets, the child must be resumed before
1737
               the parent vfork event is delivered.  A single-step
1738
               suffices. */
1739
            if (RESUME_EXECD_VFORKING_CHILD_TO_GET_PARENT_VFORK ())
1740
              target_resume (ecs->ptid, 1, TARGET_SIGNAL_0);
1741
            /* We expect the parent vfork event to be available now. */
1742
            prepare_to_wait (ecs);
1743
            return;
1744
          }
1745
 
1746
        /* This causes the eventpoints and symbol table to be reset.  Must
1747
           do this now, before trying to determine whether to stop. */
1748
        follow_exec (PIDGET (inferior_ptid), pending_follow.execd_pathname);
1749
        xfree (pending_follow.execd_pathname);
1750
 
1751
        stop_pc = read_pc_pid (ecs->ptid);
1752
        ecs->saved_inferior_ptid = inferior_ptid;
1753
        inferior_ptid = ecs->ptid;
1754
        /* The second argument of bpstat_stop_status is meant to help
1755
           distinguish between a breakpoint trap and a singlestep trap.
1756
           This is only important on targets where DECR_PC_AFTER_BREAK
1757
           is non-zero.  The prev_pc test is meant to distinguish between
1758
           singlestepping a trap instruction, and singlestepping thru a
1759
           jump to the instruction following a trap instruction. */
1760
 
1761
        stop_bpstat = bpstat_stop_status (&stop_pc,
1762
                                          currently_stepping (ecs) &&
1763
                                          prev_pc !=
1764
                                          stop_pc - DECR_PC_AFTER_BREAK);
1765
        ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
1766
        inferior_ptid = ecs->saved_inferior_ptid;
1767
        goto process_event_stop_test;
1768
 
1769
        /* These syscall events are returned on HP-UX, as part of its
1770
           implementation of page-protection-based "hardware" watchpoints.
1771
           HP-UX has unfortunate interactions between page-protections and
1772
           some system calls.  Our solution is to disable hardware watches
1773
           when a system call is entered, and reenable them when the syscall
1774
           completes.  The downside of this is that we may miss the precise
1775
           point at which a watched piece of memory is modified.  "Oh well."
1776
 
1777
           Note that we may have multiple threads running, which may each
1778
           enter syscalls at roughly the same time.  Since we don't have a
1779
           good notion currently of whether a watched piece of memory is
1780
           thread-private, we'd best not have any page-protections active
1781
           when any thread is in a syscall.  Thus, we only want to reenable
1782
           hardware watches when no threads are in a syscall.
1783
 
1784
           Also, be careful not to try to gather much state about a thread
1785
           that's in a syscall.  It's frequently a losing proposition. */
1786
      case TARGET_WAITKIND_SYSCALL_ENTRY:
1787
        number_of_threads_in_syscalls++;
1788
        if (number_of_threads_in_syscalls == 1)
1789
          {
1790
            TARGET_DISABLE_HW_WATCHPOINTS (PIDGET (inferior_ptid));
1791
          }
1792
        resume (0, TARGET_SIGNAL_0);
1793
        prepare_to_wait (ecs);
1794
        return;
1795
 
1796
        /* Before examining the threads further, step this thread to
1797
           get it entirely out of the syscall.  (We get notice of the
1798
           event when the thread is just on the verge of exiting a
1799
           syscall.  Stepping one instruction seems to get it back
1800
           into user code.)
1801
 
1802
           Note that although the logical place to reenable h/w watches
1803
           is here, we cannot.  We cannot reenable them before stepping
1804
           the thread (this causes the next wait on the thread to hang).
1805
 
1806
           Nor can we enable them after stepping until we've done a wait.
1807
           Thus, we simply set the flag ecs->enable_hw_watchpoints_after_wait
1808
           here, which will be serviced immediately after the target
1809
           is waited on. */
1810
      case TARGET_WAITKIND_SYSCALL_RETURN:
1811
        target_resume (ecs->ptid, 1, TARGET_SIGNAL_0);
1812
 
1813
        if (number_of_threads_in_syscalls > 0)
1814
          {
1815
            number_of_threads_in_syscalls--;
1816
            ecs->enable_hw_watchpoints_after_wait =
1817
              (number_of_threads_in_syscalls == 0);
1818
          }
1819
        prepare_to_wait (ecs);
1820
        return;
1821
 
1822
      case TARGET_WAITKIND_STOPPED:
1823
        stop_signal = ecs->ws.value.sig;
1824
        break;
1825
 
1826
        /* We had an event in the inferior, but we are not interested
1827
           in handling it at this level. The lower layers have already
1828
           done what needs to be done, if anything. This case can
1829
           occur only when the target is async or extended-async. One
1830
           of the circumstamces for this to happen is when the
1831
           inferior produces output for the console. The inferior has
1832
           not stopped, and we are ignoring the event. */
1833
      case TARGET_WAITKIND_IGNORE:
1834
        ecs->wait_some_more = 1;
1835
        return;
1836
      }
1837
 
1838
    /* We may want to consider not doing a resume here in order to give
1839
       the user a chance to play with the new thread.  It might be good
1840
       to make that a user-settable option.  */
1841
 
1842
    /* At this point, all threads are stopped (happens automatically in
1843
       either the OS or the native code).  Therefore we need to continue
1844
       all threads in order to make progress.  */
1845
    if (ecs->new_thread_event)
1846
      {
1847
        target_resume (RESUME_ALL, 0, TARGET_SIGNAL_0);
1848
        prepare_to_wait (ecs);
1849
        return;
1850
      }
1851
 
1852
    stop_pc = read_pc_pid (ecs->ptid);
1853
 
1854
    /* See if a thread hit a thread-specific breakpoint that was meant for
1855
       another thread.  If so, then step that thread past the breakpoint,
1856
       and continue it.  */
1857
 
1858
    if (stop_signal == TARGET_SIGNAL_TRAP)
1859
      {
1860
        if (SOFTWARE_SINGLE_STEP_P () && singlestep_breakpoints_inserted_p)
1861
          ecs->random_signal = 0;
1862
        else if (breakpoints_inserted
1863
                 && breakpoint_here_p (stop_pc - DECR_PC_AFTER_BREAK))
1864
          {
1865
            ecs->random_signal = 0;
1866
            if (!breakpoint_thread_match (stop_pc - DECR_PC_AFTER_BREAK,
1867
                                          ecs->ptid))
1868
              {
1869
                int remove_status;
1870
 
1871
                /* Saw a breakpoint, but it was hit by the wrong thread.
1872
                   Just continue. */
1873
                if (DECR_PC_AFTER_BREAK)
1874
                  write_pc_pid (stop_pc - DECR_PC_AFTER_BREAK, ecs->ptid);
1875
 
1876
                remove_status = remove_breakpoints ();
1877
                /* Did we fail to remove breakpoints?  If so, try
1878
                   to set the PC past the bp.  (There's at least
1879
                   one situation in which we can fail to remove
1880
                   the bp's: On HP-UX's that use ttrace, we can't
1881
                   change the address space of a vforking child
1882
                   process until the child exits (well, okay, not
1883
                   then either :-) or execs. */
1884
                if (remove_status != 0)
1885
                  {
1886
                    /* FIXME!  This is obviously non-portable! */
1887
                    write_pc_pid (stop_pc - DECR_PC_AFTER_BREAK + 4,
1888
                                  ecs->ptid);
1889
                    /* We need to restart all the threads now,
1890
                     * unles we're running in scheduler-locked mode.
1891
                     * Use currently_stepping to determine whether to
1892
                     * step or continue.
1893
                     */
1894
                    /* FIXME MVS: is there any reason not to call resume()? */
1895
                    if (scheduler_mode == schedlock_on)
1896
                      target_resume (ecs->ptid,
1897
                                     currently_stepping (ecs),
1898
                                     TARGET_SIGNAL_0);
1899
                    else
1900
                      target_resume (RESUME_ALL,
1901
                                     currently_stepping (ecs),
1902
                                     TARGET_SIGNAL_0);
1903
                    prepare_to_wait (ecs);
1904
                    return;
1905
                  }
1906
                else
1907
                  {             /* Single step */
1908
                    breakpoints_inserted = 0;
1909
                    if (!ptid_equal (inferior_ptid, ecs->ptid))
1910
                      context_switch (ecs);
1911
                    ecs->waiton_ptid = ecs->ptid;
1912
                    ecs->wp = &(ecs->ws);
1913
                    ecs->another_trap = 1;
1914
 
1915
                    ecs->infwait_state = infwait_thread_hop_state;
1916
                    keep_going (ecs);
1917
                    registers_changed ();
1918
                    return;
1919
                  }
1920
              }
1921
          }
1922
      }
1923
    else
1924
      ecs->random_signal = 1;
1925
 
1926
    /* See if something interesting happened to the non-current thread.  If
1927
       so, then switch to that thread, and eventually give control back to
1928
       the user.
1929
 
1930
       Note that if there's any kind of pending follow (i.e., of a fork,
1931
       vfork or exec), we don't want to do this now.  Rather, we'll let
1932
       the next resume handle it. */
1933
    if (! ptid_equal (ecs->ptid, inferior_ptid) &&
1934
        (pending_follow.kind == TARGET_WAITKIND_SPURIOUS))
1935
      {
1936
        int printed = 0;
1937
 
1938
        /* If it's a random signal for a non-current thread, notify user
1939
           if he's expressed an interest. */
1940
        if (ecs->random_signal
1941
            && signal_print[stop_signal])
1942
          {
1943
/* ??rehrauer: I don't understand the rationale for this code.  If the
1944
   inferior will stop as a result of this signal, then the act of handling
1945
   the stop ought to print a message that's couches the stoppage in user
1946
   terms, e.g., "Stopped for breakpoint/watchpoint".  If the inferior
1947
   won't stop as a result of the signal -- i.e., if the signal is merely
1948
   a side-effect of something GDB's doing "under the covers" for the
1949
   user, such as stepping threads over a breakpoint they shouldn't stop
1950
   for -- then the message seems to be a serious annoyance at best.
1951
 
1952
   For now, remove the message altogether. */
1953
#if 0
1954
            printed = 1;
1955
            target_terminal_ours_for_output ();
1956
            printf_filtered ("\nProgram received signal %s, %s.\n",
1957
                             target_signal_to_name (stop_signal),
1958
                             target_signal_to_string (stop_signal));
1959
            gdb_flush (gdb_stdout);
1960
#endif
1961
          }
1962
 
1963
        /* If it's not SIGTRAP and not a signal we want to stop for, then
1964
           continue the thread. */
1965
 
1966
        if (stop_signal != TARGET_SIGNAL_TRAP
1967
            && !signal_stop[stop_signal])
1968
          {
1969
            if (printed)
1970
              target_terminal_inferior ();
1971
 
1972
            /* Clear the signal if it should not be passed.  */
1973
            if (signal_program[stop_signal] == 0)
1974
              stop_signal = TARGET_SIGNAL_0;
1975
 
1976
            target_resume (ecs->ptid, 0, stop_signal);
1977
            prepare_to_wait (ecs);
1978
            return;
1979
          }
1980
 
1981
        /* It's a SIGTRAP or a signal we're interested in.  Switch threads,
1982
           and fall into the rest of wait_for_inferior().  */
1983
 
1984
        context_switch (ecs);
1985
 
1986
        if (context_hook)
1987
          context_hook (pid_to_thread_id (ecs->ptid));
1988
 
1989
        flush_cached_frames ();
1990
      }
1991
 
1992
    if (SOFTWARE_SINGLE_STEP_P () && singlestep_breakpoints_inserted_p)
1993
      {
1994
        /* Pull the single step breakpoints out of the target. */
1995
        SOFTWARE_SINGLE_STEP (0, 0);
1996
        singlestep_breakpoints_inserted_p = 0;
1997
      }
1998
 
1999
    /* If PC is pointing at a nullified instruction, then step beyond
2000
       it so that the user won't be confused when GDB appears to be ready
2001
       to execute it. */
2002
 
2003
    /*      if (INSTRUCTION_NULLIFIED && currently_stepping (ecs)) */
2004
    if (INSTRUCTION_NULLIFIED)
2005
      {
2006
        registers_changed ();
2007
        target_resume (ecs->ptid, 1, TARGET_SIGNAL_0);
2008
 
2009
        /* We may have received a signal that we want to pass to
2010
           the inferior; therefore, we must not clobber the waitstatus
2011
           in WS. */
2012
 
2013
        ecs->infwait_state = infwait_nullified_state;
2014
        ecs->waiton_ptid = ecs->ptid;
2015
        ecs->wp = &(ecs->tmpstatus);
2016
        prepare_to_wait (ecs);
2017
        return;
2018
      }
2019
 
2020
    /* It may not be necessary to disable the watchpoint to stop over
2021
       it.  For example, the PA can (with some kernel cooperation)
2022
       single step over a watchpoint without disabling the watchpoint.  */
2023
    if (HAVE_STEPPABLE_WATCHPOINT && STOPPED_BY_WATCHPOINT (ecs->ws))
2024
      {
2025
        resume (1, 0);
2026
        prepare_to_wait (ecs);
2027
        return;
2028
      }
2029
 
2030
    /* It is far more common to need to disable a watchpoint to step
2031
       the inferior over it.  FIXME.  What else might a debug
2032
       register or page protection watchpoint scheme need here?  */
2033
    if (HAVE_NONSTEPPABLE_WATCHPOINT && STOPPED_BY_WATCHPOINT (ecs->ws))
2034
      {
2035
        /* At this point, we are stopped at an instruction which has
2036
           attempted to write to a piece of memory under control of
2037
           a watchpoint.  The instruction hasn't actually executed
2038
           yet.  If we were to evaluate the watchpoint expression
2039
           now, we would get the old value, and therefore no change
2040
           would seem to have occurred.
2041
 
2042
           In order to make watchpoints work `right', we really need
2043
           to complete the memory write, and then evaluate the
2044
           watchpoint expression.  The following code does that by
2045
           removing the watchpoint (actually, all watchpoints and
2046
           breakpoints), single-stepping the target, re-inserting
2047
           watchpoints, and then falling through to let normal
2048
           single-step processing handle proceed.  Since this
2049
           includes evaluating watchpoints, things will come to a
2050
           stop in the correct manner.  */
2051
 
2052
        if (DECR_PC_AFTER_BREAK)
2053
          write_pc (stop_pc - DECR_PC_AFTER_BREAK);
2054
 
2055
        remove_breakpoints ();
2056
        registers_changed ();
2057
        target_resume (ecs->ptid, 1, TARGET_SIGNAL_0);  /* Single step */
2058
 
2059
        ecs->waiton_ptid = ecs->ptid;
2060
        ecs->wp = &(ecs->ws);
2061
        ecs->infwait_state = infwait_nonstep_watch_state;
2062
        prepare_to_wait (ecs);
2063
        return;
2064
      }
2065
 
2066
    /* It may be possible to simply continue after a watchpoint.  */
2067
    if (HAVE_CONTINUABLE_WATCHPOINT)
2068
      STOPPED_BY_WATCHPOINT (ecs->ws);
2069
 
2070
    ecs->stop_func_start = 0;
2071
    ecs->stop_func_end = 0;
2072
    ecs->stop_func_name = 0;
2073
    /* Don't care about return value; stop_func_start and stop_func_name
2074
       will both be 0 if it doesn't work.  */
2075
    find_pc_partial_function (stop_pc, &ecs->stop_func_name,
2076
                              &ecs->stop_func_start, &ecs->stop_func_end);
2077
    ecs->stop_func_start += FUNCTION_START_OFFSET;
2078
    ecs->another_trap = 0;
2079
    bpstat_clear (&stop_bpstat);
2080
    stop_step = 0;
2081
    stop_stack_dummy = 0;
2082
    stop_print_frame = 1;
2083
    ecs->random_signal = 0;
2084
    stopped_by_random_signal = 0;
2085
    breakpoints_failed = 0;
2086
 
2087
    /* Look at the cause of the stop, and decide what to do.
2088
       The alternatives are:
2089
       1) break; to really stop and return to the debugger,
2090
       2) drop through to start up again
2091
       (set ecs->another_trap to 1 to single step once)
2092
       3) set ecs->random_signal to 1, and the decision between 1 and 2
2093
       will be made according to the signal handling tables.  */
2094
 
2095
    /* First, distinguish signals caused by the debugger from signals
2096
       that have to do with the program's own actions.
2097
       Note that breakpoint insns may cause SIGTRAP or SIGILL
2098
       or SIGEMT, depending on the operating system version.
2099
       Here we detect when a SIGILL or SIGEMT is really a breakpoint
2100
       and change it to SIGTRAP.  */
2101
 
2102
    if (stop_signal == TARGET_SIGNAL_TRAP
2103
        || (breakpoints_inserted &&
2104
            (stop_signal == TARGET_SIGNAL_ILL
2105
             || stop_signal == TARGET_SIGNAL_EMT
2106
            ))
2107
        || stop_soon_quietly)
2108
      {
2109
        if (stop_signal == TARGET_SIGNAL_TRAP && stop_after_trap)
2110
          {
2111
            stop_print_frame = 0;
2112
            stop_stepping (ecs);
2113
            return;
2114
          }
2115
        if (stop_soon_quietly)
2116
          {
2117
            stop_stepping (ecs);
2118
            return;
2119
          }
2120
 
2121
        /* Don't even think about breakpoints
2122
           if just proceeded over a breakpoint.
2123
 
2124
           However, if we are trying to proceed over a breakpoint
2125
           and end up in sigtramp, then through_sigtramp_breakpoint
2126
           will be set and we should check whether we've hit the
2127
           step breakpoint.  */
2128
        if (stop_signal == TARGET_SIGNAL_TRAP && trap_expected
2129
            && through_sigtramp_breakpoint == NULL)
2130
          bpstat_clear (&stop_bpstat);
2131
        else
2132
          {
2133
            /* See if there is a breakpoint at the current PC.  */
2134
 
2135
            /* The second argument of bpstat_stop_status is meant to help
2136
               distinguish between a breakpoint trap and a singlestep trap.
2137
               This is only important on targets where DECR_PC_AFTER_BREAK
2138
               is non-zero.  The prev_pc test is meant to distinguish between
2139
               singlestepping a trap instruction, and singlestepping thru a
2140
               jump to the instruction following a trap instruction. */
2141
 
2142
            stop_bpstat = bpstat_stop_status
2143
              (&stop_pc,
2144
            /* Pass TRUE if our reason for stopping is something other
2145
               than hitting a breakpoint.  We do this by checking that
2146
               1) stepping is going on and 2) we didn't hit a breakpoint
2147
               in a signal handler without an intervening stop in
2148
               sigtramp, which is detected by a new stack pointer value
2149
               below any usual function calling stack adjustments.  */
2150
                (currently_stepping (ecs)
2151
                 && prev_pc != stop_pc - DECR_PC_AFTER_BREAK
2152
                 && !(step_range_end
2153
                      && INNER_THAN (read_sp (), (step_sp - 16))))
2154
              );
2155
            /* Following in case break condition called a
2156
               function.  */
2157
            stop_print_frame = 1;
2158
          }
2159
 
2160
        if (stop_signal == TARGET_SIGNAL_TRAP)
2161
          ecs->random_signal
2162
            = !(bpstat_explains_signal (stop_bpstat)
2163
                || trap_expected
2164
                || (!CALL_DUMMY_BREAKPOINT_OFFSET_P
2165
                    && PC_IN_CALL_DUMMY (stop_pc, read_sp (),
2166
                                         FRAME_FP (get_current_frame ())))
2167
                || (step_range_end && step_resume_breakpoint == NULL));
2168
 
2169
        else
2170
          {
2171
            ecs->random_signal
2172
              = !(bpstat_explains_signal (stop_bpstat)
2173
            /* End of a stack dummy.  Some systems (e.g. Sony
2174
               news) give another signal besides SIGTRAP, so
2175
               check here as well as above.  */
2176
                  || (!CALL_DUMMY_BREAKPOINT_OFFSET_P
2177
                      && PC_IN_CALL_DUMMY (stop_pc, read_sp (),
2178
                                           FRAME_FP (get_current_frame ())))
2179
              );
2180
            if (!ecs->random_signal)
2181
              stop_signal = TARGET_SIGNAL_TRAP;
2182
          }
2183
      }
2184
 
2185
    /* When we reach this point, we've pretty much decided
2186
       that the reason for stopping must've been a random
2187
       (unexpected) signal. */
2188
 
2189
    else
2190
      ecs->random_signal = 1;
2191
    /* If a fork, vfork or exec event was seen, then there are two
2192
       possible responses we can make:
2193
 
2194
       1. If a catchpoint triggers for the event (ecs->random_signal == 0),
2195
       then we must stop now and issue a prompt.  We will resume
2196
       the inferior when the user tells us to.
2197
       2. If no catchpoint triggers for the event (ecs->random_signal == 1),
2198
       then we must resume the inferior now and keep checking.
2199
 
2200
       In either case, we must take appropriate steps to "follow" the
2201
       the fork/vfork/exec when the inferior is resumed.  For example,
2202
       if follow-fork-mode is "child", then we must detach from the
2203
       parent inferior and follow the new child inferior.
2204
 
2205
       In either case, setting pending_follow causes the next resume()
2206
       to take the appropriate following action. */
2207
  process_event_stop_test:
2208
    if (ecs->ws.kind == TARGET_WAITKIND_FORKED)
2209
      {
2210
        if (ecs->random_signal) /* I.e., no catchpoint triggered for this. */
2211
          {
2212
            trap_expected = 1;
2213
            stop_signal = TARGET_SIGNAL_0;
2214
            keep_going (ecs);
2215
            return;
2216
          }
2217
      }
2218
    else if (ecs->ws.kind == TARGET_WAITKIND_VFORKED)
2219
      {
2220
        if (ecs->random_signal) /* I.e., no catchpoint triggered for this. */
2221
          {
2222
            stop_signal = TARGET_SIGNAL_0;
2223
            keep_going (ecs);
2224
            return;
2225
          }
2226
      }
2227
    else if (ecs->ws.kind == TARGET_WAITKIND_EXECD)
2228
      {
2229
        pending_follow.kind = ecs->ws.kind;
2230
        if (ecs->random_signal) /* I.e., no catchpoint triggered for this. */
2231
          {
2232
            trap_expected = 1;
2233
            stop_signal = TARGET_SIGNAL_0;
2234
            keep_going (ecs);
2235
            return;
2236
          }
2237
      }
2238
 
2239
    /* For the program's own signals, act according to
2240
       the signal handling tables.  */
2241
 
2242
    if (ecs->random_signal)
2243
      {
2244
        /* Signal not for debugging purposes.  */
2245
        int printed = 0;
2246
 
2247
        stopped_by_random_signal = 1;
2248
 
2249
        if (signal_print[stop_signal])
2250
          {
2251
            printed = 1;
2252
            target_terminal_ours_for_output ();
2253
            print_stop_reason (SIGNAL_RECEIVED, stop_signal);
2254
          }
2255
        if (signal_stop[stop_signal])
2256
          {
2257
            stop_stepping (ecs);
2258
            return;
2259
          }
2260
        /* If not going to stop, give terminal back
2261
           if we took it away.  */
2262
        else if (printed)
2263
          target_terminal_inferior ();
2264
 
2265
        /* Clear the signal if it should not be passed.  */
2266
        if (signal_program[stop_signal] == 0)
2267
          stop_signal = TARGET_SIGNAL_0;
2268
 
2269
        /* I'm not sure whether this needs to be check_sigtramp2 or
2270
           whether it could/should be keep_going.
2271
 
2272
           This used to jump to step_over_function if we are stepping,
2273
           which is wrong.
2274
 
2275
           Suppose the user does a `next' over a function call, and while
2276
           that call is in progress, the inferior receives a signal for
2277
           which GDB does not stop (i.e., signal_stop[SIG] is false).  In
2278
           that case, when we reach this point, there is already a
2279
           step-resume breakpoint established, right where it should be:
2280
           immediately after the function call the user is "next"-ing
2281
           over.  If we call step_over_function now, two bad things
2282
           happen:
2283
 
2284
           - we'll create a new breakpoint, at wherever the current
2285
             frame's return address happens to be.  That could be
2286
             anywhere, depending on what function call happens to be on
2287
             the top of the stack at that point.  Point is, it's probably
2288
             not where we need it.
2289
 
2290
           - the existing step-resume breakpoint (which is at the correct
2291
             address) will get orphaned: step_resume_breakpoint will point
2292
             to the new breakpoint, and the old step-resume breakpoint
2293
             will never be cleaned up.
2294
 
2295
           The old behavior was meant to help HP-UX single-step out of
2296
           sigtramps.  It would place the new breakpoint at prev_pc, which
2297
           was certainly wrong.  I don't know the details there, so fixing
2298
           this probably breaks that.  As with anything else, it's up to
2299
           the HP-UX maintainer to furnish a fix that doesn't break other
2300
           platforms.  --JimB, 20 May 1999 */
2301
        check_sigtramp2 (ecs);
2302
        keep_going (ecs);
2303
        return;
2304
      }
2305
 
2306
    /* Handle cases caused by hitting a breakpoint.  */
2307
    {
2308
      CORE_ADDR jmp_buf_pc;
2309
      struct bpstat_what what;
2310
 
2311
      what = bpstat_what (stop_bpstat);
2312
 
2313
      if (what.call_dummy)
2314
        {
2315
          stop_stack_dummy = 1;
2316
#ifdef HP_OS_BUG
2317
          trap_expected_after_continue = 1;
2318
#endif
2319
        }
2320
 
2321
      switch (what.main_action)
2322
        {
2323
        case BPSTAT_WHAT_SET_LONGJMP_RESUME:
2324
          /* If we hit the breakpoint at longjmp, disable it for the
2325
             duration of this command.  Then, install a temporary
2326
             breakpoint at the target of the jmp_buf. */
2327
          disable_longjmp_breakpoint ();
2328
          remove_breakpoints ();
2329
          breakpoints_inserted = 0;
2330
          if (!GET_LONGJMP_TARGET (&jmp_buf_pc))
2331
            {
2332
              keep_going (ecs);
2333
              return;
2334
            }
2335
 
2336
          /* Need to blow away step-resume breakpoint, as it
2337
             interferes with us */
2338
          if (step_resume_breakpoint != NULL)
2339
            {
2340
              delete_step_resume_breakpoint (&step_resume_breakpoint);
2341
            }
2342
          /* Not sure whether we need to blow this away too, but probably
2343
             it is like the step-resume breakpoint.  */
2344
          if (through_sigtramp_breakpoint != NULL)
2345
            {
2346
              delete_breakpoint (through_sigtramp_breakpoint);
2347
              through_sigtramp_breakpoint = NULL;
2348
            }
2349
 
2350
#if 0
2351
          /* FIXME - Need to implement nested temporary breakpoints */
2352
          if (step_over_calls > 0)
2353
            set_longjmp_resume_breakpoint (jmp_buf_pc,
2354
                                           get_current_frame ());
2355
          else
2356
#endif /* 0 */
2357
            set_longjmp_resume_breakpoint (jmp_buf_pc, NULL);
2358
          ecs->handling_longjmp = 1;    /* FIXME */
2359
          keep_going (ecs);
2360
          return;
2361
 
2362
        case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME:
2363
        case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME_SINGLE:
2364
          remove_breakpoints ();
2365
          breakpoints_inserted = 0;
2366
#if 0
2367
          /* FIXME - Need to implement nested temporary breakpoints */
2368
          if (step_over_calls
2369
              && (INNER_THAN (FRAME_FP (get_current_frame ()),
2370
                              step_frame_address)))
2371
            {
2372
              ecs->another_trap = 1;
2373
              keep_going (ecs);
2374
              return;
2375
            }
2376
#endif /* 0 */
2377
          disable_longjmp_breakpoint ();
2378
          ecs->handling_longjmp = 0;     /* FIXME */
2379
          if (what.main_action == BPSTAT_WHAT_CLEAR_LONGJMP_RESUME)
2380
            break;
2381
          /* else fallthrough */
2382
 
2383
        case BPSTAT_WHAT_SINGLE:
2384
          if (breakpoints_inserted)
2385
            {
2386
              remove_breakpoints ();
2387
            }
2388
          breakpoints_inserted = 0;
2389
          ecs->another_trap = 1;
2390
          /* Still need to check other stuff, at least the case
2391
             where we are stepping and step out of the right range.  */
2392
          break;
2393
 
2394
        case BPSTAT_WHAT_STOP_NOISY:
2395
          stop_print_frame = 1;
2396
 
2397
          /* We are about to nuke the step_resume_breakpoint and
2398
             through_sigtramp_breakpoint via the cleanup chain, so
2399
             no need to worry about it here.  */
2400
 
2401
          stop_stepping (ecs);
2402
          return;
2403
 
2404
        case BPSTAT_WHAT_STOP_SILENT:
2405
          stop_print_frame = 0;
2406
 
2407
          /* We are about to nuke the step_resume_breakpoint and
2408
             through_sigtramp_breakpoint via the cleanup chain, so
2409
             no need to worry about it here.  */
2410
 
2411
          stop_stepping (ecs);
2412
          return;
2413
 
2414
        case BPSTAT_WHAT_STEP_RESUME:
2415
          /* This proably demands a more elegant solution, but, yeah
2416
             right...
2417
 
2418
             This function's use of the simple variable
2419
             step_resume_breakpoint doesn't seem to accomodate
2420
             simultaneously active step-resume bp's, although the
2421
             breakpoint list certainly can.
2422
 
2423
             If we reach here and step_resume_breakpoint is already
2424
             NULL, then apparently we have multiple active
2425
             step-resume bp's.  We'll just delete the breakpoint we
2426
             stopped at, and carry on.
2427
 
2428
             Correction: what the code currently does is delete a
2429
             step-resume bp, but it makes no effort to ensure that
2430
             the one deleted is the one currently stopped at.  MVS  */
2431
 
2432
          if (step_resume_breakpoint == NULL)
2433
            {
2434
              step_resume_breakpoint =
2435
                bpstat_find_step_resume_breakpoint (stop_bpstat);
2436
            }
2437
          delete_step_resume_breakpoint (&step_resume_breakpoint);
2438
          break;
2439
 
2440
        case BPSTAT_WHAT_THROUGH_SIGTRAMP:
2441
          if (through_sigtramp_breakpoint)
2442
            delete_breakpoint (through_sigtramp_breakpoint);
2443
          through_sigtramp_breakpoint = NULL;
2444
 
2445
          /* If were waiting for a trap, hitting the step_resume_break
2446
             doesn't count as getting it.  */
2447
          if (trap_expected)
2448
            ecs->another_trap = 1;
2449
          break;
2450
 
2451
        case BPSTAT_WHAT_CHECK_SHLIBS:
2452
        case BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK:
2453
#ifdef SOLIB_ADD
2454
          {
2455
            /* Remove breakpoints, we eventually want to step over the
2456
               shlib event breakpoint, and SOLIB_ADD might adjust
2457
               breakpoint addresses via breakpoint_re_set.  */
2458
            if (breakpoints_inserted)
2459
              remove_breakpoints ();
2460
            breakpoints_inserted = 0;
2461
 
2462
            /* Check for any newly added shared libraries if we're
2463
               supposed to be adding them automatically.  */
2464
            if (auto_solib_add)
2465
              {
2466
                /* Switch terminal for any messages produced by
2467
                   breakpoint_re_set.  */
2468
                target_terminal_ours_for_output ();
2469
                SOLIB_ADD (NULL, 0, NULL);
2470
                target_terminal_inferior ();
2471
              }
2472
 
2473
            /* Try to reenable shared library breakpoints, additional
2474
               code segments in shared libraries might be mapped in now. */
2475
            re_enable_breakpoints_in_shlibs ();
2476
 
2477
            /* If requested, stop when the dynamic linker notifies
2478
               gdb of events.  This allows the user to get control
2479
               and place breakpoints in initializer routines for
2480
               dynamically loaded objects (among other things).  */
2481
            if (stop_on_solib_events)
2482
              {
2483
                stop_stepping (ecs);
2484
                return;
2485
              }
2486
 
2487
            /* If we stopped due to an explicit catchpoint, then the
2488
               (see above) call to SOLIB_ADD pulled in any symbols
2489
               from a newly-loaded library, if appropriate.
2490
 
2491
               We do want the inferior to stop, but not where it is
2492
               now, which is in the dynamic linker callback.  Rather,
2493
               we would like it stop in the user's program, just after
2494
               the call that caused this catchpoint to trigger.  That
2495
               gives the user a more useful vantage from which to
2496
               examine their program's state. */
2497
            else if (what.main_action == BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK)
2498
              {
2499
                /* ??rehrauer: If I could figure out how to get the
2500
                   right return PC from here, we could just set a temp
2501
                   breakpoint and resume.  I'm not sure we can without
2502
                   cracking open the dld's shared libraries and sniffing
2503
                   their unwind tables and text/data ranges, and that's
2504
                   not a terribly portable notion.
2505
 
2506
                   Until that time, we must step the inferior out of the
2507
                   dld callback, and also out of the dld itself (and any
2508
                   code or stubs in libdld.sl, such as "shl_load" and
2509
                   friends) until we reach non-dld code.  At that point,
2510
                   we can stop stepping. */
2511
                bpstat_get_triggered_catchpoints (stop_bpstat,
2512
                                  &ecs->stepping_through_solib_catchpoints);
2513
                ecs->stepping_through_solib_after_catch = 1;
2514
 
2515
                /* Be sure to lift all breakpoints, so the inferior does
2516
                   actually step past this point... */
2517
                ecs->another_trap = 1;
2518
                break;
2519
              }
2520
            else
2521
              {
2522
                /* We want to step over this breakpoint, then keep going.  */
2523
                ecs->another_trap = 1;
2524
                break;
2525
              }
2526
          }
2527
#endif
2528
          break;
2529
 
2530
        case BPSTAT_WHAT_LAST:
2531
          /* Not a real code, but listed here to shut up gcc -Wall.  */
2532
 
2533
        case BPSTAT_WHAT_KEEP_CHECKING:
2534
          break;
2535
        }
2536
    }
2537
 
2538
    /* We come here if we hit a breakpoint but should not
2539
       stop for it.  Possibly we also were stepping
2540
       and should stop for that.  So fall through and
2541
       test for stepping.  But, if not stepping,
2542
       do not stop.  */
2543
 
2544
    /* Are we stepping to get the inferior out of the dynamic
2545
       linker's hook (and possibly the dld itself) after catching
2546
       a shlib event? */
2547
    if (ecs->stepping_through_solib_after_catch)
2548
      {
2549
#if defined(SOLIB_ADD)
2550
        /* Have we reached our destination?  If not, keep going. */
2551
        if (SOLIB_IN_DYNAMIC_LINKER (PIDGET (ecs->ptid), stop_pc))
2552
          {
2553
            ecs->another_trap = 1;
2554
            keep_going (ecs);
2555
            return;
2556
          }
2557
#endif
2558
        /* Else, stop and report the catchpoint(s) whose triggering
2559
           caused us to begin stepping. */
2560
        ecs->stepping_through_solib_after_catch = 0;
2561
        bpstat_clear (&stop_bpstat);
2562
        stop_bpstat = bpstat_copy (ecs->stepping_through_solib_catchpoints);
2563
        bpstat_clear (&ecs->stepping_through_solib_catchpoints);
2564
        stop_print_frame = 1;
2565
        stop_stepping (ecs);
2566
        return;
2567
      }
2568
 
2569
    if (!CALL_DUMMY_BREAKPOINT_OFFSET_P)
2570
      {
2571
        /* This is the old way of detecting the end of the stack dummy.
2572
           An architecture which defines CALL_DUMMY_BREAKPOINT_OFFSET gets
2573
           handled above.  As soon as we can test it on all of them, all
2574
           architectures should define it.  */
2575
 
2576
        /* If this is the breakpoint at the end of a stack dummy,
2577
           just stop silently, unless the user was doing an si/ni, in which
2578
           case she'd better know what she's doing.  */
2579
 
2580
        if (CALL_DUMMY_HAS_COMPLETED (stop_pc, read_sp (),
2581
                                      FRAME_FP (get_current_frame ()))
2582
            && !step_range_end)
2583
          {
2584
            stop_print_frame = 0;
2585
            stop_stack_dummy = 1;
2586
#ifdef HP_OS_BUG
2587
            trap_expected_after_continue = 1;
2588
#endif
2589
            stop_stepping (ecs);
2590
            return;
2591
          }
2592
      }
2593
 
2594
    if (step_resume_breakpoint)
2595
      {
2596
        /* Having a step-resume breakpoint overrides anything
2597
           else having to do with stepping commands until
2598
           that breakpoint is reached.  */
2599
        /* I'm not sure whether this needs to be check_sigtramp2 or
2600
           whether it could/should be keep_going.  */
2601
        check_sigtramp2 (ecs);
2602
        keep_going (ecs);
2603
        return;
2604
      }
2605
 
2606
    if (step_range_end == 0)
2607
      {
2608
        /* Likewise if we aren't even stepping.  */
2609
        /* I'm not sure whether this needs to be check_sigtramp2 or
2610
           whether it could/should be keep_going.  */
2611
        check_sigtramp2 (ecs);
2612
        keep_going (ecs);
2613
        return;
2614
      }
2615
 
2616
    /* If stepping through a line, keep going if still within it.
2617
 
2618
       Note that step_range_end is the address of the first instruction
2619
       beyond the step range, and NOT the address of the last instruction
2620
       within it! */
2621
    if (stop_pc >= step_range_start
2622
        && stop_pc < step_range_end)
2623
      {
2624
        /* We might be doing a BPSTAT_WHAT_SINGLE and getting a signal.
2625
           So definately need to check for sigtramp here.  */
2626
        check_sigtramp2 (ecs);
2627
        keep_going (ecs);
2628
        return;
2629
      }
2630
 
2631
    /* We stepped out of the stepping range.  */
2632
 
2633
    /* If we are stepping at the source level and entered the runtime
2634
       loader dynamic symbol resolution code, we keep on single stepping
2635
       until we exit the run time loader code and reach the callee's
2636
       address.  */
2637
    if (step_over_calls == STEP_OVER_UNDEBUGGABLE && IN_SOLIB_DYNSYM_RESOLVE_CODE (stop_pc))
2638
      {
2639
        CORE_ADDR pc_after_resolver = SKIP_SOLIB_RESOLVER (stop_pc);
2640
 
2641
        if (pc_after_resolver)
2642
          {
2643
            /* Set up a step-resume breakpoint at the address
2644
               indicated by SKIP_SOLIB_RESOLVER.  */
2645
            struct symtab_and_line sr_sal;
2646
            INIT_SAL (&sr_sal);
2647
            sr_sal.pc = pc_after_resolver;
2648
 
2649
            check_for_old_step_resume_breakpoint ();
2650
            step_resume_breakpoint =
2651
              set_momentary_breakpoint (sr_sal, NULL, bp_step_resume);
2652
            if (breakpoints_inserted)
2653
              insert_breakpoints ();
2654
          }
2655
 
2656
        keep_going (ecs);
2657
        return;
2658
      }
2659
 
2660
    /* We can't update step_sp every time through the loop, because
2661
       reading the stack pointer would slow down stepping too much.
2662
       But we can update it every time we leave the step range.  */
2663
    ecs->update_step_sp = 1;
2664
 
2665
    /* Did we just take a signal?  */
2666
    if (IN_SIGTRAMP (stop_pc, ecs->stop_func_name)
2667
        && !IN_SIGTRAMP (prev_pc, prev_func_name)
2668
        && INNER_THAN (read_sp (), step_sp))
2669
      {
2670
        /* We've just taken a signal; go until we are back to
2671
           the point where we took it and one more.  */
2672
 
2673
        /* Note: The test above succeeds not only when we stepped
2674
           into a signal handler, but also when we step past the last
2675
           statement of a signal handler and end up in the return stub
2676
           of the signal handler trampoline.  To distinguish between
2677
           these two cases, check that the frame is INNER_THAN the
2678
           previous one below. pai/1997-09-11 */
2679
 
2680
 
2681
        {
2682
          CORE_ADDR current_frame = FRAME_FP (get_current_frame ());
2683
 
2684
          if (INNER_THAN (current_frame, step_frame_address))
2685
            {
2686
              /* We have just taken a signal; go until we are back to
2687
                 the point where we took it and one more.  */
2688
 
2689
              /* This code is needed at least in the following case:
2690
                 The user types "next" and then a signal arrives (before
2691
                 the "next" is done).  */
2692
 
2693
              /* Note that if we are stopped at a breakpoint, then we need
2694
                 the step_resume breakpoint to override any breakpoints at
2695
                 the same location, so that we will still step over the
2696
                 breakpoint even though the signal happened.  */
2697
              struct symtab_and_line sr_sal;
2698
 
2699
              INIT_SAL (&sr_sal);
2700
              sr_sal.symtab = NULL;
2701
              sr_sal.line = 0;
2702
              sr_sal.pc = prev_pc;
2703
              /* We could probably be setting the frame to
2704
                 step_frame_address; I don't think anyone thought to
2705
                 try it.  */
2706
              check_for_old_step_resume_breakpoint ();
2707
              step_resume_breakpoint =
2708
                set_momentary_breakpoint (sr_sal, NULL, bp_step_resume);
2709
              if (breakpoints_inserted)
2710
                insert_breakpoints ();
2711
            }
2712
          else
2713
            {
2714
              /* We just stepped out of a signal handler and into
2715
                 its calling trampoline.
2716
 
2717
                 Normally, we'd call step_over_function from
2718
                 here, but for some reason GDB can't unwind the
2719
                 stack correctly to find the real PC for the point
2720
                 user code where the signal trampoline will return
2721
                 -- FRAME_SAVED_PC fails, at least on HP-UX 10.20.
2722
                 But signal trampolines are pretty small stubs of
2723
                 code, anyway, so it's OK instead to just
2724
                 single-step out.  Note: assuming such trampolines
2725
                 don't exhibit recursion on any platform... */
2726
              find_pc_partial_function (stop_pc, &ecs->stop_func_name,
2727
                                        &ecs->stop_func_start,
2728
                                        &ecs->stop_func_end);
2729
              /* Readjust stepping range */
2730
              step_range_start = ecs->stop_func_start;
2731
              step_range_end = ecs->stop_func_end;
2732
              ecs->stepping_through_sigtramp = 1;
2733
            }
2734
        }
2735
 
2736
 
2737
        /* If this is stepi or nexti, make sure that the stepping range
2738
           gets us past that instruction.  */
2739
        if (step_range_end == 1)
2740
          /* FIXME: Does this run afoul of the code below which, if
2741
             we step into the middle of a line, resets the stepping
2742
             range?  */
2743
          step_range_end = (step_range_start = prev_pc) + 1;
2744
 
2745
        ecs->remove_breakpoints_on_following_step = 1;
2746
        keep_going (ecs);
2747
        return;
2748
      }
2749
 
2750
    if (stop_pc == ecs->stop_func_start         /* Quick test */
2751
        || (in_prologue (stop_pc, ecs->stop_func_start) &&
2752
            !IN_SOLIB_RETURN_TRAMPOLINE (stop_pc, ecs->stop_func_name))
2753
        || IN_SOLIB_CALL_TRAMPOLINE (stop_pc, ecs->stop_func_name)
2754
        || ecs->stop_func_name == 0)
2755
      {
2756
        /* It's a subroutine call.  */
2757
 
2758
        if ((step_over_calls == STEP_OVER_NONE)
2759
            || ((step_range_end == 1)
2760
                && in_prologue (prev_pc, ecs->stop_func_start)))
2761
          {
2762
            /* I presume that step_over_calls is only 0 when we're
2763
               supposed to be stepping at the assembly language level
2764
               ("stepi").  Just stop.  */
2765
            /* Also, maybe we just did a "nexti" inside a prolog,
2766
               so we thought it was a subroutine call but it was not.
2767
               Stop as well.  FENN */
2768
            stop_step = 1;
2769
            print_stop_reason (END_STEPPING_RANGE, 0);
2770
            stop_stepping (ecs);
2771
            return;
2772
          }
2773
 
2774
        if (step_over_calls == STEP_OVER_ALL || IGNORE_HELPER_CALL (stop_pc))
2775
          {
2776
            /* We're doing a "next".  */
2777
 
2778
            if (IN_SIGTRAMP (stop_pc, ecs->stop_func_name)
2779
                && INNER_THAN (step_frame_address, read_sp()))
2780
              /* We stepped out of a signal handler, and into its
2781
                 calling trampoline.  This is misdetected as a
2782
                 subroutine call, but stepping over the signal
2783
                 trampoline isn't such a bad idea.  In order to do
2784
                 that, we have to ignore the value in
2785
                 step_frame_address, since that doesn't represent the
2786
                 frame that'll reach when we return from the signal
2787
                 trampoline.  Otherwise we'll probably continue to the
2788
                 end of the program.  */
2789
              step_frame_address = 0;
2790
 
2791
            step_over_function (ecs);
2792
            keep_going (ecs);
2793
            return;
2794
          }
2795
 
2796
        /* If we are in a function call trampoline (a stub between
2797
           the calling routine and the real function), locate the real
2798
           function.  That's what tells us (a) whether we want to step
2799
           into it at all, and (b) what prologue we want to run to
2800
           the end of, if we do step into it.  */
2801
        tmp = SKIP_TRAMPOLINE_CODE (stop_pc);
2802
        if (tmp != 0)
2803
          ecs->stop_func_start = tmp;
2804
        else
2805
          {
2806
            tmp = DYNAMIC_TRAMPOLINE_NEXTPC (stop_pc);
2807
            if (tmp)
2808
              {
2809
                struct symtab_and_line xxx;
2810
                /* Why isn't this s_a_l called "sr_sal", like all of the
2811
                   other s_a_l's where this code is duplicated?  */
2812
                INIT_SAL (&xxx);        /* initialize to zeroes */
2813
                xxx.pc = tmp;
2814
                xxx.section = find_pc_overlay (xxx.pc);
2815
                check_for_old_step_resume_breakpoint ();
2816
                step_resume_breakpoint =
2817
                  set_momentary_breakpoint (xxx, NULL, bp_step_resume);
2818
                insert_breakpoints ();
2819
                keep_going (ecs);
2820
                return;
2821
              }
2822
          }
2823
 
2824
        /* If we have line number information for the function we
2825
           are thinking of stepping into, step into it.
2826
 
2827
           If there are several symtabs at that PC (e.g. with include
2828
           files), just want to know whether *any* of them have line
2829
           numbers.  find_pc_line handles this.  */
2830
        {
2831
          struct symtab_and_line tmp_sal;
2832
 
2833
          tmp_sal = find_pc_line (ecs->stop_func_start, 0);
2834
          if (tmp_sal.line != 0)
2835
            {
2836
              step_into_function (ecs);
2837
              return;
2838
            }
2839
        }
2840
 
2841
        /* If we have no line number and the step-stop-if-no-debug
2842
           is set, we stop the step so that the user has a chance to
2843
           switch in assembly mode.  */
2844
        if (step_over_calls == STEP_OVER_UNDEBUGGABLE && step_stop_if_no_debug)
2845
          {
2846
            stop_step = 1;
2847
            print_stop_reason (END_STEPPING_RANGE, 0);
2848
            stop_stepping (ecs);
2849
            return;
2850
          }
2851
 
2852
        step_over_function (ecs);
2853
        keep_going (ecs);
2854
        return;
2855
 
2856
      }
2857
 
2858
    /* We've wandered out of the step range.  */
2859
 
2860
    ecs->sal = find_pc_line (stop_pc, 0);
2861
 
2862
    if (step_range_end == 1)
2863
      {
2864
        /* It is stepi or nexti.  We always want to stop stepping after
2865
           one instruction.  */
2866
        stop_step = 1;
2867
        print_stop_reason (END_STEPPING_RANGE, 0);
2868
        stop_stepping (ecs);
2869
        return;
2870
      }
2871
 
2872
    /* If we're in the return path from a shared library trampoline,
2873
       we want to proceed through the trampoline when stepping.  */
2874
    if (IN_SOLIB_RETURN_TRAMPOLINE (stop_pc, ecs->stop_func_name))
2875
      {
2876
        CORE_ADDR tmp;
2877
 
2878
        /* Determine where this trampoline returns.  */
2879
        tmp = SKIP_TRAMPOLINE_CODE (stop_pc);
2880
 
2881
        /* Only proceed through if we know where it's going.  */
2882
        if (tmp)
2883
          {
2884
            /* And put the step-breakpoint there and go until there. */
2885
            struct symtab_and_line sr_sal;
2886
 
2887
            INIT_SAL (&sr_sal); /* initialize to zeroes */
2888
            sr_sal.pc = tmp;
2889
            sr_sal.section = find_pc_overlay (sr_sal.pc);
2890
            /* Do not specify what the fp should be when we stop
2891
               since on some machines the prologue
2892
               is where the new fp value is established.  */
2893
            check_for_old_step_resume_breakpoint ();
2894
            step_resume_breakpoint =
2895
              set_momentary_breakpoint (sr_sal, NULL, bp_step_resume);
2896
            if (breakpoints_inserted)
2897
              insert_breakpoints ();
2898
 
2899
            /* Restart without fiddling with the step ranges or
2900
               other state.  */
2901
            keep_going (ecs);
2902
            return;
2903
          }
2904
      }
2905
 
2906
    if (ecs->sal.line == 0)
2907
      {
2908
        /* We have no line number information.  That means to stop
2909
           stepping (does this always happen right after one instruction,
2910
           when we do "s" in a function with no line numbers,
2911
           or can this happen as a result of a return or longjmp?).  */
2912
        stop_step = 1;
2913
        print_stop_reason (END_STEPPING_RANGE, 0);
2914
        stop_stepping (ecs);
2915
        return;
2916
      }
2917
 
2918
    if ((stop_pc == ecs->sal.pc)
2919
        && (ecs->current_line != ecs->sal.line || ecs->current_symtab != ecs->sal.symtab))
2920
      {
2921
        /* We are at the start of a different line.  So stop.  Note that
2922
           we don't stop if we step into the middle of a different line.
2923
           That is said to make things like for (;;) statements work
2924
           better.  */
2925
        stop_step = 1;
2926
        print_stop_reason (END_STEPPING_RANGE, 0);
2927
        stop_stepping (ecs);
2928
        return;
2929
      }
2930
 
2931
    /* We aren't done stepping.
2932
 
2933
       Optimize by setting the stepping range to the line.
2934
       (We might not be in the original line, but if we entered a
2935
       new line in mid-statement, we continue stepping.  This makes
2936
       things like for(;;) statements work better.)  */
2937
 
2938
    if (ecs->stop_func_end && ecs->sal.end >= ecs->stop_func_end)
2939
      {
2940
        /* If this is the last line of the function, don't keep stepping
2941
           (it would probably step us out of the function).
2942
           This is particularly necessary for a one-line function,
2943
           in which after skipping the prologue we better stop even though
2944
           we will be in mid-line.  */
2945
        stop_step = 1;
2946
        print_stop_reason (END_STEPPING_RANGE, 0);
2947
        stop_stepping (ecs);
2948
        return;
2949
      }
2950
    step_range_start = ecs->sal.pc;
2951
    step_range_end = ecs->sal.end;
2952
    step_frame_address = FRAME_FP (get_current_frame ());
2953
    ecs->current_line = ecs->sal.line;
2954
    ecs->current_symtab = ecs->sal.symtab;
2955
 
2956
    /* In the case where we just stepped out of a function into the middle
2957
       of a line of the caller, continue stepping, but step_frame_address
2958
       must be modified to current frame */
2959
    {
2960
      CORE_ADDR current_frame = FRAME_FP (get_current_frame ());
2961
      if (!(INNER_THAN (current_frame, step_frame_address)))
2962
        step_frame_address = current_frame;
2963
    }
2964
 
2965
    keep_going (ecs);
2966
 
2967
  } /* extra brace, to preserve old indentation */
2968
}
2969
 
2970
/* Are we in the middle of stepping?  */
2971
 
2972
static int
2973
currently_stepping (struct execution_control_state *ecs)
2974
{
2975
  return ((through_sigtramp_breakpoint == NULL
2976
           && !ecs->handling_longjmp
2977
           && ((step_range_end && step_resume_breakpoint == NULL)
2978
               || trap_expected))
2979
          || ecs->stepping_through_solib_after_catch
2980
          || bpstat_should_step ());
2981
}
2982
 
2983
static void
2984
check_sigtramp2 (struct execution_control_state *ecs)
2985
{
2986
  if (trap_expected
2987
      && IN_SIGTRAMP (stop_pc, ecs->stop_func_name)
2988
      && !IN_SIGTRAMP (prev_pc, prev_func_name)
2989
      && INNER_THAN (read_sp (), step_sp))
2990
    {
2991
      /* What has happened here is that we have just stepped the
2992
         inferior with a signal (because it is a signal which
2993
         shouldn't make us stop), thus stepping into sigtramp.
2994
 
2995
         So we need to set a step_resume_break_address breakpoint and
2996
         continue until we hit it, and then step.  FIXME: This should
2997
         be more enduring than a step_resume breakpoint; we should
2998
         know that we will later need to keep going rather than
2999
         re-hitting the breakpoint here (see the testsuite,
3000
         gdb.base/signals.exp where it says "exceedingly difficult").  */
3001
 
3002
      struct symtab_and_line sr_sal;
3003
 
3004
      INIT_SAL (&sr_sal);       /* initialize to zeroes */
3005
      sr_sal.pc = prev_pc;
3006
      sr_sal.section = find_pc_overlay (sr_sal.pc);
3007
      /* We perhaps could set the frame if we kept track of what the
3008
         frame corresponding to prev_pc was.  But we don't, so don't.  */
3009
      through_sigtramp_breakpoint =
3010
        set_momentary_breakpoint (sr_sal, NULL, bp_through_sigtramp);
3011
      if (breakpoints_inserted)
3012
        insert_breakpoints ();
3013
 
3014
      ecs->remove_breakpoints_on_following_step = 1;
3015
      ecs->another_trap = 1;
3016
    }
3017
}
3018
 
3019
/* Subroutine call with source code we should not step over.  Do step
3020
   to the first line of code in it.  */
3021
 
3022
static void
3023
step_into_function (struct execution_control_state *ecs)
3024
{
3025
  struct symtab *s;
3026
  struct symtab_and_line sr_sal;
3027
 
3028
  s = find_pc_symtab (stop_pc);
3029
  if (s && s->language != language_asm)
3030
    ecs->stop_func_start = SKIP_PROLOGUE (ecs->stop_func_start);
3031
 
3032
  ecs->sal = find_pc_line (ecs->stop_func_start, 0);
3033
  /* Use the step_resume_break to step until the end of the prologue,
3034
     even if that involves jumps (as it seems to on the vax under
3035
     4.2).  */
3036
  /* If the prologue ends in the middle of a source line, continue to
3037
     the end of that source line (if it is still within the function).
3038
     Otherwise, just go to end of prologue.  */
3039
#ifdef PROLOGUE_FIRSTLINE_OVERLAP
3040
  /* no, don't either.  It skips any code that's legitimately on the
3041
     first line.  */
3042
#else
3043
  if (ecs->sal.end
3044
      && ecs->sal.pc != ecs->stop_func_start
3045
      && ecs->sal.end < ecs->stop_func_end)
3046
    ecs->stop_func_start = ecs->sal.end;
3047
#endif
3048
 
3049
  if (ecs->stop_func_start == stop_pc)
3050
    {
3051
      /* We are already there: stop now.  */
3052
      stop_step = 1;
3053
        print_stop_reason (END_STEPPING_RANGE, 0);
3054
      stop_stepping (ecs);
3055
      return;
3056
    }
3057
  else
3058
    {
3059
      /* Put the step-breakpoint there and go until there.  */
3060
      INIT_SAL (&sr_sal);       /* initialize to zeroes */
3061
      sr_sal.pc = ecs->stop_func_start;
3062
      sr_sal.section = find_pc_overlay (ecs->stop_func_start);
3063
      /* Do not specify what the fp should be when we stop since on
3064
         some machines the prologue is where the new fp value is
3065
         established.  */
3066
      check_for_old_step_resume_breakpoint ();
3067
      step_resume_breakpoint =
3068
        set_momentary_breakpoint (sr_sal, NULL, bp_step_resume);
3069
      if (breakpoints_inserted)
3070
        insert_breakpoints ();
3071
 
3072
      /* And make sure stepping stops right away then.  */
3073
      step_range_end = step_range_start;
3074
    }
3075
  keep_going (ecs);
3076
}
3077
 
3078
/* We've just entered a callee, and we wish to resume until it returns
3079
   to the caller.  Setting a step_resume breakpoint on the return
3080
   address will catch a return from the callee.
3081
 
3082
   However, if the callee is recursing, we want to be careful not to
3083
   catch returns of those recursive calls, but only of THIS instance
3084
   of the call.
3085
 
3086
   To do this, we set the step_resume bp's frame to our current
3087
   caller's frame (step_frame_address, which is set by the "next" or
3088
   "until" command, before execution begins).  */
3089
 
3090
static void
3091
step_over_function (struct execution_control_state *ecs)
3092
{
3093
  struct symtab_and_line sr_sal;
3094
 
3095
  INIT_SAL (&sr_sal);   /* initialize to zeros */
3096
  sr_sal.pc = ADDR_BITS_REMOVE (SAVED_PC_AFTER_CALL (get_current_frame ()));
3097
  sr_sal.section = find_pc_overlay (sr_sal.pc);
3098
 
3099
  check_for_old_step_resume_breakpoint ();
3100
  step_resume_breakpoint =
3101
    set_momentary_breakpoint (sr_sal, get_current_frame (), bp_step_resume);
3102
 
3103
  if (step_frame_address && !IN_SOLIB_DYNSYM_RESOLVE_CODE (sr_sal.pc))
3104
    step_resume_breakpoint->frame = step_frame_address;
3105
 
3106
  if (breakpoints_inserted)
3107
    insert_breakpoints ();
3108
}
3109
 
3110
static void
3111
stop_stepping (struct execution_control_state *ecs)
3112
{
3113
  if (target_has_execution)
3114
    {
3115
      /* Are we stopping for a vfork event?  We only stop when we see
3116
         the child's event.  However, we may not yet have seen the
3117
         parent's event.  And, inferior_ptid is still set to the
3118
         parent's pid, until we resume again and follow either the
3119
         parent or child.
3120
 
3121
         To ensure that we can really touch inferior_ptid (aka, the
3122
         parent process) -- which calls to functions like read_pc
3123
         implicitly do -- wait on the parent if necessary. */
3124
      if ((pending_follow.kind == TARGET_WAITKIND_VFORKED)
3125
          && !pending_follow.fork_event.saw_parent_fork)
3126
        {
3127
          ptid_t parent_ptid;
3128
 
3129
          do
3130
            {
3131
              if (target_wait_hook)
3132
                parent_ptid = target_wait_hook (pid_to_ptid (-1), &(ecs->ws));
3133
              else
3134
                parent_ptid = target_wait (pid_to_ptid (-1), &(ecs->ws));
3135
            }
3136
          while (! ptid_equal (parent_ptid, inferior_ptid));
3137
        }
3138
 
3139
      /* Assuming the inferior still exists, set these up for next
3140
         time, just like we did above if we didn't break out of the
3141
         loop.  */
3142
      prev_pc = read_pc ();
3143
      prev_func_start = ecs->stop_func_start;
3144
      prev_func_name = ecs->stop_func_name;
3145
    }
3146
 
3147
  /* Let callers know we don't want to wait for the inferior anymore.  */
3148
  ecs->wait_some_more = 0;
3149
}
3150
 
3151
/* This function handles various cases where we need to continue
3152
   waiting for the inferior.  */
3153
/* (Used to be the keep_going: label in the old wait_for_inferior) */
3154
 
3155
static void
3156
keep_going (struct execution_control_state *ecs)
3157
{
3158
  /* ??rehrauer: ttrace on HP-UX theoretically allows one to debug a
3159
     vforked child between its creation and subsequent exit or call to
3160
     exec().  However, I had big problems in this rather creaky exec
3161
     engine, getting that to work.  The fundamental problem is that
3162
     I'm trying to debug two processes via an engine that only
3163
     understands a single process with possibly multiple threads.
3164
 
3165
     Hence, this spot is known to have problems when
3166
     target_can_follow_vfork_prior_to_exec returns 1. */
3167
 
3168
  /* Save the pc before execution, to compare with pc after stop.  */
3169
  prev_pc = read_pc (); /* Might have been DECR_AFTER_BREAK */
3170
  prev_func_start = ecs->stop_func_start;       /* Ok, since if DECR_PC_AFTER
3171
                                                   BREAK is defined, the
3172
                                                   original pc would not have
3173
                                                   been at the start of a
3174
                                                   function. */
3175
  prev_func_name = ecs->stop_func_name;
3176
 
3177
  if (ecs->update_step_sp)
3178
    step_sp = read_sp ();
3179
  ecs->update_step_sp = 0;
3180
 
3181
  /* If we did not do break;, it means we should keep running the
3182
     inferior and not return to debugger.  */
3183
 
3184
  if (trap_expected && stop_signal != TARGET_SIGNAL_TRAP)
3185
    {
3186
      /* We took a signal (which we are supposed to pass through to
3187
         the inferior, else we'd have done a break above) and we
3188
         haven't yet gotten our trap.  Simply continue.  */
3189
      resume (currently_stepping (ecs), stop_signal);
3190
    }
3191
  else
3192
    {
3193
      /* Either the trap was not expected, but we are continuing
3194
         anyway (the user asked that this signal be passed to the
3195
         child)
3196
         -- or --
3197
         The signal was SIGTRAP, e.g. it was our signal, but we
3198
         decided we should resume from it.
3199
 
3200
         We're going to run this baby now!
3201
 
3202
         Insert breakpoints now, unless we are trying to one-proceed
3203
         past a breakpoint.  */
3204
      /* If we've just finished a special step resume and we don't
3205
         want to hit a breakpoint, pull em out.  */
3206
      if (step_resume_breakpoint == NULL
3207
          && through_sigtramp_breakpoint == NULL
3208
          && ecs->remove_breakpoints_on_following_step)
3209
        {
3210
          ecs->remove_breakpoints_on_following_step = 0;
3211
          remove_breakpoints ();
3212
          breakpoints_inserted = 0;
3213
        }
3214
      else if (!breakpoints_inserted &&
3215
               (through_sigtramp_breakpoint != NULL || !ecs->another_trap))
3216
        {
3217
          breakpoints_failed = insert_breakpoints ();
3218
          if (breakpoints_failed)
3219
            {
3220
              stop_stepping (ecs);
3221
              return;
3222
            }
3223
          breakpoints_inserted = 1;
3224
        }
3225
 
3226
      trap_expected = ecs->another_trap;
3227
 
3228
      /* Do not deliver SIGNAL_TRAP (except when the user explicitly
3229
         specifies that such a signal should be delivered to the
3230
         target program).
3231
 
3232
         Typically, this would occure when a user is debugging a
3233
         target monitor on a simulator: the target monitor sets a
3234
         breakpoint; the simulator encounters this break-point and
3235
         halts the simulation handing control to GDB; GDB, noteing
3236
         that the break-point isn't valid, returns control back to the
3237
         simulator; the simulator then delivers the hardware
3238
         equivalent of a SIGNAL_TRAP to the program being debugged. */
3239
 
3240
      if (stop_signal == TARGET_SIGNAL_TRAP
3241
          && !signal_program[stop_signal])
3242
        stop_signal = TARGET_SIGNAL_0;
3243
 
3244
#ifdef SHIFT_INST_REGS
3245
      /* I'm not sure when this following segment applies.  I do know,
3246
         now, that we shouldn't rewrite the regs when we were stopped
3247
         by a random signal from the inferior process.  */
3248
      /* FIXME: Shouldn't this be based on the valid bit of the SXIP?
3249
         (this is only used on the 88k).  */
3250
 
3251
      if (!bpstat_explains_signal (stop_bpstat)
3252
          && (stop_signal != TARGET_SIGNAL_CHLD)
3253
          && !stopped_by_random_signal)
3254
        SHIFT_INST_REGS ();
3255
#endif /* SHIFT_INST_REGS */
3256
 
3257
      resume (currently_stepping (ecs), stop_signal);
3258
    }
3259
 
3260
    prepare_to_wait (ecs);
3261
}
3262
 
3263
/* This function normally comes after a resume, before
3264
   handle_inferior_event exits.  It takes care of any last bits of
3265
   housekeeping, and sets the all-important wait_some_more flag.  */
3266
 
3267
static void
3268
prepare_to_wait (struct execution_control_state *ecs)
3269
{
3270
  if (ecs->infwait_state == infwait_normal_state)
3271
    {
3272
      overlay_cache_invalid = 1;
3273
 
3274
      /* We have to invalidate the registers BEFORE calling
3275
         target_wait because they can be loaded from the target while
3276
         in target_wait.  This makes remote debugging a bit more
3277
         efficient for those targets that provide critical registers
3278
         as part of their normal status mechanism. */
3279
 
3280
      registers_changed ();
3281
      ecs->waiton_ptid = pid_to_ptid (-1);
3282
      ecs->wp = &(ecs->ws);
3283
    }
3284
  /* This is the old end of the while loop.  Let everybody know we
3285
     want to wait for the inferior some more and get called again
3286
     soon.  */
3287
  ecs->wait_some_more = 1;
3288
}
3289
 
3290
/* Print why the inferior has stopped. We always print something when
3291
   the inferior exits, or receives a signal. The rest of the cases are
3292
   dealt with later on in normal_stop() and print_it_typical().  Ideally
3293
   there should be a call to this function from handle_inferior_event()
3294
   each time stop_stepping() is called.*/
3295
static void
3296
print_stop_reason (enum inferior_stop_reason stop_reason, int stop_info)
3297
{
3298
  switch (stop_reason)
3299
    {
3300
    case STOP_UNKNOWN:
3301
      /* We don't deal with these cases from handle_inferior_event()
3302
         yet. */
3303
      break;
3304
    case END_STEPPING_RANGE:
3305
      /* We are done with a step/next/si/ni command. */
3306
      /* For now print nothing. */
3307
#ifdef UI_OUT
3308
      /* Print a message only if not in the middle of doing a "step n"
3309
         operation for n > 1 */
3310
      if (!step_multi || !stop_step)
3311
        if (ui_out_is_mi_like_p (uiout))
3312
          ui_out_field_string (uiout, "reason", "end-stepping-range");
3313
#endif
3314
      break;
3315
    case BREAKPOINT_HIT:
3316
      /* We found a breakpoint. */
3317
      /* For now print nothing. */
3318
      break;
3319
    case SIGNAL_EXITED:
3320
      /* The inferior was terminated by a signal. */
3321
#ifdef UI_OUT
3322
      annotate_signalled ();
3323
      if (ui_out_is_mi_like_p (uiout))
3324
        ui_out_field_string (uiout, "reason", "exited-signalled");
3325
      ui_out_text (uiout, "\nProgram terminated with signal ");
3326
      annotate_signal_name ();
3327
      ui_out_field_string (uiout, "signal-name", target_signal_to_name (stop_info));
3328
      annotate_signal_name_end ();
3329
      ui_out_text (uiout, ", ");
3330
      annotate_signal_string ();
3331
      ui_out_field_string (uiout, "signal-meaning", target_signal_to_string (stop_info));
3332
      annotate_signal_string_end ();
3333
      ui_out_text (uiout, ".\n");
3334
      ui_out_text (uiout, "The program no longer exists.\n");
3335
#else
3336
      annotate_signalled ();
3337
      printf_filtered ("\nProgram terminated with signal ");
3338
      annotate_signal_name ();
3339
      printf_filtered ("%s", target_signal_to_name (stop_info));
3340
      annotate_signal_name_end ();
3341
      printf_filtered (", ");
3342
      annotate_signal_string ();
3343
      printf_filtered ("%s", target_signal_to_string (stop_info));
3344
      annotate_signal_string_end ();
3345
      printf_filtered (".\n");
3346
 
3347
      printf_filtered ("The program no longer exists.\n");
3348
      gdb_flush (gdb_stdout);
3349
#endif
3350
      break;
3351
    case EXITED:
3352
      /* The inferior program is finished. */
3353
#ifdef UI_OUT
3354
      annotate_exited (stop_info);
3355
      if (stop_info)
3356
        {
3357
          if (ui_out_is_mi_like_p (uiout))
3358
            ui_out_field_string (uiout, "reason", "exited");
3359
          ui_out_text (uiout, "\nProgram exited with code ");
3360
          ui_out_field_fmt (uiout, "exit-code", "0%o", (unsigned int) stop_info);
3361
          ui_out_text (uiout, ".\n");
3362
        }
3363
      else
3364
        {
3365
          if (ui_out_is_mi_like_p (uiout))
3366
            ui_out_field_string (uiout, "reason", "exited-normally");
3367
          ui_out_text (uiout, "\nProgram exited normally.\n");
3368
        }
3369
#else
3370
      annotate_exited (stop_info);
3371
      if (stop_info)
3372
        printf_filtered ("\nProgram exited with code 0%o.\n",
3373
                         (unsigned int) stop_info);
3374
      else
3375
        printf_filtered ("\nProgram exited normally.\n");
3376
#endif
3377
      break;
3378
    case SIGNAL_RECEIVED:
3379
      /* Signal received. The signal table tells us to print about
3380
         it. */
3381
#ifdef UI_OUT
3382
      annotate_signal ();
3383
      ui_out_text (uiout, "\nProgram received signal ");
3384
      annotate_signal_name ();
3385
      ui_out_field_string (uiout, "signal-name", target_signal_to_name (stop_info));
3386
      annotate_signal_name_end ();
3387
      ui_out_text (uiout, ", ");
3388
      annotate_signal_string ();
3389
      ui_out_field_string (uiout, "signal-meaning", target_signal_to_string (stop_info));
3390
      annotate_signal_string_end ();
3391
      ui_out_text (uiout, ".\n");
3392
#else
3393
      annotate_signal ();
3394
      printf_filtered ("\nProgram received signal ");
3395
      annotate_signal_name ();
3396
      printf_filtered ("%s", target_signal_to_name (stop_info));
3397
      annotate_signal_name_end ();
3398
      printf_filtered (", ");
3399
      annotate_signal_string ();
3400
      printf_filtered ("%s", target_signal_to_string (stop_info));
3401
      annotate_signal_string_end ();
3402
      printf_filtered (".\n");
3403
      gdb_flush (gdb_stdout);
3404
#endif
3405
      break;
3406
    default:
3407
      internal_error (__FILE__, __LINE__,
3408
                      "print_stop_reason: unrecognized enum value");
3409
      break;
3410
    }
3411
}
3412
 
3413
 
3414
/* Here to return control to GDB when the inferior stops for real.
3415
   Print appropriate messages, remove breakpoints, give terminal our modes.
3416
 
3417
   STOP_PRINT_FRAME nonzero means print the executing frame
3418
   (pc, function, args, file, line number and line text).
3419
   BREAKPOINTS_FAILED nonzero means stop was due to error
3420
   attempting to insert breakpoints.  */
3421
 
3422
void
3423
normal_stop (void)
3424
{
3425
  /* As with the notification of thread events, we want to delay
3426
     notifying the user that we've switched thread context until
3427
     the inferior actually stops.
3428
 
3429
     (Note that there's no point in saying anything if the inferior
3430
     has exited!) */
3431
  if (! ptid_equal (previous_inferior_ptid, inferior_ptid)
3432
      && target_has_execution)
3433
    {
3434
      target_terminal_ours_for_output ();
3435
      printf_filtered ("[Switching to %s]\n",
3436
                       target_pid_or_tid_to_str (inferior_ptid));
3437
      previous_inferior_ptid = inferior_ptid;
3438
    }
3439
 
3440
  /* Make sure that the current_frame's pc is correct.  This
3441
     is a correction for setting up the frame info before doing
3442
     DECR_PC_AFTER_BREAK */
3443
  if (target_has_execution && get_current_frame ())
3444
    (get_current_frame ())->pc = read_pc ();
3445
 
3446
  if (breakpoints_failed)
3447
    {
3448
      target_terminal_ours_for_output ();
3449
      print_sys_errmsg ("While inserting breakpoints", breakpoints_failed);
3450
      printf_filtered ("Stopped; cannot insert breakpoints.\n\
3451
The same program may be running in another process,\n\
3452
or you may have requested too many hardware breakpoints\n\
3453
and/or watchpoints.\n");
3454
    }
3455
 
3456
  if (target_has_execution && breakpoints_inserted)
3457
    {
3458
      if (remove_breakpoints ())
3459
        {
3460
          target_terminal_ours_for_output ();
3461
          printf_filtered ("Cannot remove breakpoints because ");
3462
          printf_filtered ("program is no longer writable.\n");
3463
          printf_filtered ("It might be running in another process.\n");
3464
          printf_filtered ("Further execution is probably impossible.\n");
3465
        }
3466
    }
3467
  breakpoints_inserted = 0;
3468
 
3469
  /* Delete the breakpoint we stopped at, if it wants to be deleted.
3470
     Delete any breakpoint that is to be deleted at the next stop.  */
3471
 
3472
  breakpoint_auto_delete (stop_bpstat);
3473
 
3474
  /* If an auto-display called a function and that got a signal,
3475
     delete that auto-display to avoid an infinite recursion.  */
3476
 
3477
  if (stopped_by_random_signal)
3478
    disable_current_display ();
3479
 
3480
  /* Don't print a message if in the middle of doing a "step n"
3481
     operation for n > 1 */
3482
  if (step_multi && stop_step)
3483
    goto done;
3484
 
3485
  target_terminal_ours ();
3486
 
3487
  /* Look up the hook_stop and run it if it exists.  */
3488
 
3489
  if (stop_command && stop_command->hook_pre)
3490
    {
3491
      catch_errors (hook_stop_stub, stop_command->hook_pre,
3492
                    "Error while running hook_stop:\n", RETURN_MASK_ALL);
3493
    }
3494
 
3495
  if (!target_has_stack)
3496
    {
3497
 
3498
      goto done;
3499
    }
3500
 
3501
  /* Select innermost stack frame - i.e., current frame is frame 0,
3502
     and current location is based on that.
3503
     Don't do this on return from a stack dummy routine,
3504
     or if the program has exited. */
3505
 
3506
  if (!stop_stack_dummy)
3507
    {
3508
      select_frame (get_current_frame (), 0);
3509
 
3510
      /* Print current location without a level number, if
3511
         we have changed functions or hit a breakpoint.
3512
         Print source line if we have one.
3513
         bpstat_print() contains the logic deciding in detail
3514
         what to print, based on the event(s) that just occurred. */
3515
 
3516
      if (stop_print_frame
3517
          && selected_frame)
3518
        {
3519
          int bpstat_ret;
3520
          int source_flag;
3521
          int do_frame_printing = 1;
3522
 
3523
          bpstat_ret = bpstat_print (stop_bpstat);
3524
          switch (bpstat_ret)
3525
            {
3526
            case PRINT_UNKNOWN:
3527
              if (stop_step
3528
                  && step_frame_address == FRAME_FP (get_current_frame ())
3529
                  && step_start_function == find_pc_function (stop_pc))
3530
                source_flag = SRC_LINE;   /* finished step, just print source line */
3531
              else
3532
                source_flag = SRC_AND_LOC;    /* print location and source line */
3533
              break;
3534
            case PRINT_SRC_AND_LOC:
3535
              source_flag = SRC_AND_LOC;    /* print location and source line */
3536
              break;
3537
            case PRINT_SRC_ONLY:
3538
              source_flag = SRC_LINE;
3539
              break;
3540
            case PRINT_NOTHING:
3541
              source_flag = SRC_LINE; /* something bogus */
3542
              do_frame_printing = 0;
3543
              break;
3544
            default:
3545
              internal_error (__FILE__, __LINE__,
3546
                              "Unknown value.");
3547
            }
3548
#ifdef UI_OUT
3549
          /* For mi, have the same behavior every time we stop:
3550
             print everything but the source line. */
3551
          if (ui_out_is_mi_like_p (uiout))
3552
            source_flag = LOC_AND_ADDRESS;
3553
#endif
3554
 
3555
#ifdef UI_OUT
3556
          if (ui_out_is_mi_like_p (uiout))
3557
            ui_out_field_int (uiout, "thread-id",
3558
                              pid_to_thread_id (inferior_ptid));
3559
#endif
3560
          /* The behavior of this routine with respect to the source
3561
             flag is:
3562
             SRC_LINE: Print only source line
3563
             LOCATION: Print only location
3564
             SRC_AND_LOC: Print location and source line */
3565
          if (do_frame_printing)
3566
            show_and_print_stack_frame (selected_frame, -1, source_flag);
3567
 
3568
          /* Display the auto-display expressions.  */
3569
          do_displays ();
3570
        }
3571
    }
3572
 
3573
  /* Save the function value return registers, if we care.
3574
     We might be about to restore their previous contents.  */
3575
  if (proceed_to_finish)
3576
    read_register_bytes (0, stop_registers, REGISTER_BYTES);
3577
 
3578
  if (stop_stack_dummy)
3579
    {
3580
      /* Pop the empty frame that contains the stack dummy.
3581
         POP_FRAME ends with a setting of the current frame, so we
3582
         can use that next. */
3583
      POP_FRAME;
3584
      /* Set stop_pc to what it was before we called the function.
3585
         Can't rely on restore_inferior_status because that only gets
3586
         called if we don't stop in the called function.  */
3587
      stop_pc = read_pc ();
3588
      select_frame (get_current_frame (), 0);
3589
    }
3590
 
3591
 
3592
  TUIDO (((TuiOpaqueFuncPtr) tui_vCheckDataValues, selected_frame));
3593
 
3594
done:
3595
  annotate_stopped ();
3596
}
3597
 
3598
static int
3599
hook_stop_stub (void *cmd)
3600
{
3601
  execute_user_command ((struct cmd_list_element *) cmd, 0);
3602
  return (0);
3603
}
3604
 
3605
int
3606
signal_stop_state (int signo)
3607
{
3608
  return signal_stop[signo];
3609
}
3610
 
3611
int
3612
signal_print_state (int signo)
3613
{
3614
  return signal_print[signo];
3615
}
3616
 
3617
int
3618
signal_pass_state (int signo)
3619
{
3620
  return signal_program[signo];
3621
}
3622
 
3623
int signal_stop_update (signo, state)
3624
     int signo;
3625
     int state;
3626
{
3627
  int ret = signal_stop[signo];
3628
  signal_stop[signo] = state;
3629
  return ret;
3630
}
3631
 
3632
int signal_print_update (signo, state)
3633
     int signo;
3634
     int state;
3635
{
3636
  int ret = signal_print[signo];
3637
  signal_print[signo] = state;
3638
  return ret;
3639
}
3640
 
3641
int signal_pass_update (signo, state)
3642
     int signo;
3643
     int state;
3644
{
3645
  int ret = signal_program[signo];
3646
  signal_program[signo] = state;
3647
  return ret;
3648
}
3649
 
3650
static void
3651
sig_print_header (void)
3652
{
3653
  printf_filtered ("\
3654
Signal        Stop\tPrint\tPass to program\tDescription\n");
3655
}
3656
 
3657
static void
3658
sig_print_info (enum target_signal oursig)
3659
{
3660
  char *name = target_signal_to_name (oursig);
3661
  int name_padding = 13 - strlen (name);
3662
 
3663
  if (name_padding <= 0)
3664
    name_padding = 0;
3665
 
3666
  printf_filtered ("%s", name);
3667
  printf_filtered ("%*.*s ", name_padding, name_padding,
3668
                   "                 ");
3669
  printf_filtered ("%s\t", signal_stop[oursig] ? "Yes" : "No");
3670
  printf_filtered ("%s\t", signal_print[oursig] ? "Yes" : "No");
3671
  printf_filtered ("%s\t\t", signal_program[oursig] ? "Yes" : "No");
3672
  printf_filtered ("%s\n", target_signal_to_string (oursig));
3673
}
3674
 
3675
/* Specify how various signals in the inferior should be handled.  */
3676
 
3677
static void
3678
handle_command (char *args, int from_tty)
3679
{
3680
  char **argv;
3681
  int digits, wordlen;
3682
  int sigfirst, signum, siglast;
3683
  enum target_signal oursig;
3684
  int allsigs;
3685
  int nsigs;
3686
  unsigned char *sigs;
3687
  struct cleanup *old_chain;
3688
 
3689
  if (args == NULL)
3690
    {
3691
      error_no_arg ("signal to handle");
3692
    }
3693
 
3694
  /* Allocate and zero an array of flags for which signals to handle. */
3695
 
3696
  nsigs = (int) TARGET_SIGNAL_LAST;
3697
  sigs = (unsigned char *) alloca (nsigs);
3698
  memset (sigs, 0, nsigs);
3699
 
3700
  /* Break the command line up into args. */
3701
 
3702
  argv = buildargv (args);
3703
  if (argv == NULL)
3704
    {
3705
      nomem (0);
3706
    }
3707
  old_chain = make_cleanup_freeargv (argv);
3708
 
3709
  /* Walk through the args, looking for signal oursigs, signal names, and
3710
     actions.  Signal numbers and signal names may be interspersed with
3711
     actions, with the actions being performed for all signals cumulatively
3712
     specified.  Signal ranges can be specified as <LOW>-<HIGH>. */
3713
 
3714
  while (*argv != NULL)
3715
    {
3716
      wordlen = strlen (*argv);
3717
      for (digits = 0; isdigit ((*argv)[digits]); digits++)
3718
        {;
3719
        }
3720
      allsigs = 0;
3721
      sigfirst = siglast = -1;
3722
 
3723
      if (wordlen >= 1 && !strncmp (*argv, "all", wordlen))
3724
        {
3725
          /* Apply action to all signals except those used by the
3726
             debugger.  Silently skip those. */
3727
          allsigs = 1;
3728
          sigfirst = 0;
3729
          siglast = nsigs - 1;
3730
        }
3731
      else if (wordlen >= 1 && !strncmp (*argv, "stop", wordlen))
3732
        {
3733
          SET_SIGS (nsigs, sigs, signal_stop);
3734
          SET_SIGS (nsigs, sigs, signal_print);
3735
        }
3736
      else if (wordlen >= 1 && !strncmp (*argv, "ignore", wordlen))
3737
        {
3738
          UNSET_SIGS (nsigs, sigs, signal_program);
3739
        }
3740
      else if (wordlen >= 2 && !strncmp (*argv, "print", wordlen))
3741
        {
3742
          SET_SIGS (nsigs, sigs, signal_print);
3743
        }
3744
      else if (wordlen >= 2 && !strncmp (*argv, "pass", wordlen))
3745
        {
3746
          SET_SIGS (nsigs, sigs, signal_program);
3747
        }
3748
      else if (wordlen >= 3 && !strncmp (*argv, "nostop", wordlen))
3749
        {
3750
          UNSET_SIGS (nsigs, sigs, signal_stop);
3751
        }
3752
      else if (wordlen >= 3 && !strncmp (*argv, "noignore", wordlen))
3753
        {
3754
          SET_SIGS (nsigs, sigs, signal_program);
3755
        }
3756
      else if (wordlen >= 4 && !strncmp (*argv, "noprint", wordlen))
3757
        {
3758
          UNSET_SIGS (nsigs, sigs, signal_print);
3759
          UNSET_SIGS (nsigs, sigs, signal_stop);
3760
        }
3761
      else if (wordlen >= 4 && !strncmp (*argv, "nopass", wordlen))
3762
        {
3763
          UNSET_SIGS (nsigs, sigs, signal_program);
3764
        }
3765
      else if (digits > 0)
3766
        {
3767
          /* It is numeric.  The numeric signal refers to our own
3768
             internal signal numbering from target.h, not to host/target
3769
             signal  number.  This is a feature; users really should be
3770
             using symbolic names anyway, and the common ones like
3771
             SIGHUP, SIGINT, SIGALRM, etc. will work right anyway.  */
3772
 
3773
          sigfirst = siglast = (int)
3774
            target_signal_from_command (atoi (*argv));
3775
          if ((*argv)[digits] == '-')
3776
            {
3777
              siglast = (int)
3778
                target_signal_from_command (atoi ((*argv) + digits + 1));
3779
            }
3780
          if (sigfirst > siglast)
3781
            {
3782
              /* Bet he didn't figure we'd think of this case... */
3783
              signum = sigfirst;
3784
              sigfirst = siglast;
3785
              siglast = signum;
3786
            }
3787
        }
3788
      else
3789
        {
3790
          oursig = target_signal_from_name (*argv);
3791
          if (oursig != TARGET_SIGNAL_UNKNOWN)
3792
            {
3793
              sigfirst = siglast = (int) oursig;
3794
            }
3795
          else
3796
            {
3797
              /* Not a number and not a recognized flag word => complain.  */
3798
              error ("Unrecognized or ambiguous flag word: \"%s\".", *argv);
3799
            }
3800
        }
3801
 
3802
      /* If any signal numbers or symbol names were found, set flags for
3803
         which signals to apply actions to. */
3804
 
3805
      for (signum = sigfirst; signum >= 0 && signum <= siglast; signum++)
3806
        {
3807
          switch ((enum target_signal) signum)
3808
            {
3809
            case TARGET_SIGNAL_TRAP:
3810
            case TARGET_SIGNAL_INT:
3811
              if (!allsigs && !sigs[signum])
3812
                {
3813
                  if (query ("%s is used by the debugger.\n\
3814
Are you sure you want to change it? ",
3815
                             target_signal_to_name
3816
                             ((enum target_signal) signum)))
3817
                    {
3818
                      sigs[signum] = 1;
3819
                    }
3820
                  else
3821
                    {
3822
                      printf_unfiltered ("Not confirmed, unchanged.\n");
3823
                      gdb_flush (gdb_stdout);
3824
                    }
3825
                }
3826
              break;
3827
            case TARGET_SIGNAL_0:
3828
            case TARGET_SIGNAL_DEFAULT:
3829
            case TARGET_SIGNAL_UNKNOWN:
3830
              /* Make sure that "all" doesn't print these.  */
3831
              break;
3832
            default:
3833
              sigs[signum] = 1;
3834
              break;
3835
            }
3836
        }
3837
 
3838
      argv++;
3839
    }
3840
 
3841
  target_notice_signals (inferior_ptid);
3842
 
3843
  if (from_tty)
3844
    {
3845
      /* Show the results.  */
3846
      sig_print_header ();
3847
      for (signum = 0; signum < nsigs; signum++)
3848
        {
3849
          if (sigs[signum])
3850
            {
3851
              sig_print_info (signum);
3852
            }
3853
        }
3854
    }
3855
 
3856
  do_cleanups (old_chain);
3857
}
3858
 
3859
static void
3860
xdb_handle_command (char *args, int from_tty)
3861
{
3862
  char **argv;
3863
  struct cleanup *old_chain;
3864
 
3865
  /* Break the command line up into args. */
3866
 
3867
  argv = buildargv (args);
3868
  if (argv == NULL)
3869
    {
3870
      nomem (0);
3871
    }
3872
  old_chain = make_cleanup_freeargv (argv);
3873
  if (argv[1] != (char *) NULL)
3874
    {
3875
      char *argBuf;
3876
      int bufLen;
3877
 
3878
      bufLen = strlen (argv[0]) + 20;
3879
      argBuf = (char *) xmalloc (bufLen);
3880
      if (argBuf)
3881
        {
3882
          int validFlag = 1;
3883
          enum target_signal oursig;
3884
 
3885
          oursig = target_signal_from_name (argv[0]);
3886
          memset (argBuf, 0, bufLen);
3887
          if (strcmp (argv[1], "Q") == 0)
3888
            sprintf (argBuf, "%s %s", argv[0], "noprint");
3889
          else
3890
            {
3891
              if (strcmp (argv[1], "s") == 0)
3892
                {
3893
                  if (!signal_stop[oursig])
3894
                    sprintf (argBuf, "%s %s", argv[0], "stop");
3895
                  else
3896
                    sprintf (argBuf, "%s %s", argv[0], "nostop");
3897
                }
3898
              else if (strcmp (argv[1], "i") == 0)
3899
                {
3900
                  if (!signal_program[oursig])
3901
                    sprintf (argBuf, "%s %s", argv[0], "pass");
3902
                  else
3903
                    sprintf (argBuf, "%s %s", argv[0], "nopass");
3904
                }
3905
              else if (strcmp (argv[1], "r") == 0)
3906
                {
3907
                  if (!signal_print[oursig])
3908
                    sprintf (argBuf, "%s %s", argv[0], "print");
3909
                  else
3910
                    sprintf (argBuf, "%s %s", argv[0], "noprint");
3911
                }
3912
              else
3913
                validFlag = 0;
3914
            }
3915
          if (validFlag)
3916
            handle_command (argBuf, from_tty);
3917
          else
3918
            printf_filtered ("Invalid signal handling flag.\n");
3919
          if (argBuf)
3920
            xfree (argBuf);
3921
        }
3922
    }
3923
  do_cleanups (old_chain);
3924
}
3925
 
3926
/* Print current contents of the tables set by the handle command.
3927
   It is possible we should just be printing signals actually used
3928
   by the current target (but for things to work right when switching
3929
   targets, all signals should be in the signal tables).  */
3930
 
3931
static void
3932
signals_info (char *signum_exp, int from_tty)
3933
{
3934
  enum target_signal oursig;
3935
  sig_print_header ();
3936
 
3937
  if (signum_exp)
3938
    {
3939
      /* First see if this is a symbol name.  */
3940
      oursig = target_signal_from_name (signum_exp);
3941
      if (oursig == TARGET_SIGNAL_UNKNOWN)
3942
        {
3943
          /* No, try numeric.  */
3944
          oursig =
3945
            target_signal_from_command (parse_and_eval_long (signum_exp));
3946
        }
3947
      sig_print_info (oursig);
3948
      return;
3949
    }
3950
 
3951
  printf_filtered ("\n");
3952
  /* These ugly casts brought to you by the native VAX compiler.  */
3953
  for (oursig = TARGET_SIGNAL_FIRST;
3954
       (int) oursig < (int) TARGET_SIGNAL_LAST;
3955
       oursig = (enum target_signal) ((int) oursig + 1))
3956
    {
3957
      QUIT;
3958
 
3959
      if (oursig != TARGET_SIGNAL_UNKNOWN
3960
          && oursig != TARGET_SIGNAL_DEFAULT
3961
          && oursig != TARGET_SIGNAL_0)
3962
        sig_print_info (oursig);
3963
    }
3964
 
3965
  printf_filtered ("\nUse the \"handle\" command to change these tables.\n");
3966
}
3967
 
3968
struct inferior_status
3969
{
3970
  enum target_signal stop_signal;
3971
  CORE_ADDR stop_pc;
3972
  bpstat stop_bpstat;
3973
  int stop_step;
3974
  int stop_stack_dummy;
3975
  int stopped_by_random_signal;
3976
  int trap_expected;
3977
  CORE_ADDR step_range_start;
3978
  CORE_ADDR step_range_end;
3979
  CORE_ADDR step_frame_address;
3980
  enum step_over_calls_kind step_over_calls;
3981
  CORE_ADDR step_resume_break_address;
3982
  int stop_after_trap;
3983
  int stop_soon_quietly;
3984
  CORE_ADDR selected_frame_address;
3985
  char *stop_registers;
3986
 
3987
  /* These are here because if call_function_by_hand has written some
3988
     registers and then decides to call error(), we better not have changed
3989
     any registers.  */
3990
  char *registers;
3991
 
3992
  int selected_level;
3993
  int breakpoint_proceeded;
3994
  int restore_stack_info;
3995
  int proceed_to_finish;
3996
};
3997
 
3998
static struct inferior_status *
3999
xmalloc_inferior_status (void)
4000
{
4001
  struct inferior_status *inf_status;
4002
  inf_status = xmalloc (sizeof (struct inferior_status));
4003
  inf_status->stop_registers = xmalloc (REGISTER_BYTES);
4004
  inf_status->registers = xmalloc (REGISTER_BYTES);
4005
  return inf_status;
4006
}
4007
 
4008
static void
4009
free_inferior_status (struct inferior_status *inf_status)
4010
{
4011
  xfree (inf_status->registers);
4012
  xfree (inf_status->stop_registers);
4013
  xfree (inf_status);
4014
}
4015
 
4016
void
4017
write_inferior_status_register (struct inferior_status *inf_status, int regno,
4018
                                LONGEST val)
4019
{
4020
  int size = REGISTER_RAW_SIZE (regno);
4021
  void *buf = alloca (size);
4022
  store_signed_integer (buf, size, val);
4023
  memcpy (&inf_status->registers[REGISTER_BYTE (regno)], buf, size);
4024
}
4025
 
4026
/* Save all of the information associated with the inferior<==>gdb
4027
   connection.  INF_STATUS is a pointer to a "struct inferior_status"
4028
   (defined in inferior.h).  */
4029
 
4030
struct inferior_status *
4031
save_inferior_status (int restore_stack_info)
4032
{
4033
  struct inferior_status *inf_status = xmalloc_inferior_status ();
4034
 
4035
  inf_status->stop_signal = stop_signal;
4036
  inf_status->stop_pc = stop_pc;
4037
  inf_status->stop_step = stop_step;
4038
  inf_status->stop_stack_dummy = stop_stack_dummy;
4039
  inf_status->stopped_by_random_signal = stopped_by_random_signal;
4040
  inf_status->trap_expected = trap_expected;
4041
  inf_status->step_range_start = step_range_start;
4042
  inf_status->step_range_end = step_range_end;
4043
  inf_status->step_frame_address = step_frame_address;
4044
  inf_status->step_over_calls = step_over_calls;
4045
  inf_status->stop_after_trap = stop_after_trap;
4046
  inf_status->stop_soon_quietly = stop_soon_quietly;
4047
  /* Save original bpstat chain here; replace it with copy of chain.
4048
     If caller's caller is walking the chain, they'll be happier if we
4049
     hand them back the original chain when restore_inferior_status is
4050
     called.  */
4051
  inf_status->stop_bpstat = stop_bpstat;
4052
  stop_bpstat = bpstat_copy (stop_bpstat);
4053
  inf_status->breakpoint_proceeded = breakpoint_proceeded;
4054
  inf_status->restore_stack_info = restore_stack_info;
4055
  inf_status->proceed_to_finish = proceed_to_finish;
4056
 
4057
  memcpy (inf_status->stop_registers, stop_registers, REGISTER_BYTES);
4058
 
4059
  read_register_bytes (0, inf_status->registers, REGISTER_BYTES);
4060
 
4061
  record_selected_frame (&(inf_status->selected_frame_address),
4062
                         &(inf_status->selected_level));
4063
  return inf_status;
4064
}
4065
 
4066
struct restore_selected_frame_args
4067
{
4068
  CORE_ADDR frame_address;
4069
  int level;
4070
};
4071
 
4072
static int
4073
restore_selected_frame (void *args)
4074
{
4075
  struct restore_selected_frame_args *fr =
4076
  (struct restore_selected_frame_args *) args;
4077
  struct frame_info *frame;
4078
  int level = fr->level;
4079
 
4080
  frame = find_relative_frame (get_current_frame (), &level);
4081
 
4082
  /* If inf_status->selected_frame_address is NULL, there was no
4083
     previously selected frame.  */
4084
  if (frame == NULL ||
4085
  /*  FRAME_FP (frame) != fr->frame_address || */
4086
  /* elz: deleted this check as a quick fix to the problem that
4087
     for function called by hand gdb creates no internal frame
4088
     structure and the real stack and gdb's idea of stack are
4089
     different if nested calls by hands are made.
4090
 
4091
     mvs: this worries me.  */
4092
      level != 0)
4093
    {
4094
      warning ("Unable to restore previously selected frame.\n");
4095
      return 0;
4096
    }
4097
 
4098
  select_frame (frame, fr->level);
4099
 
4100
  return (1);
4101
}
4102
 
4103
void
4104
restore_inferior_status (struct inferior_status *inf_status)
4105
{
4106
  stop_signal = inf_status->stop_signal;
4107
  stop_pc = inf_status->stop_pc;
4108
  stop_step = inf_status->stop_step;
4109
  stop_stack_dummy = inf_status->stop_stack_dummy;
4110
  stopped_by_random_signal = inf_status->stopped_by_random_signal;
4111
  trap_expected = inf_status->trap_expected;
4112
  step_range_start = inf_status->step_range_start;
4113
  step_range_end = inf_status->step_range_end;
4114
  step_frame_address = inf_status->step_frame_address;
4115
  step_over_calls = inf_status->step_over_calls;
4116
  stop_after_trap = inf_status->stop_after_trap;
4117
  stop_soon_quietly = inf_status->stop_soon_quietly;
4118
  bpstat_clear (&stop_bpstat);
4119
  stop_bpstat = inf_status->stop_bpstat;
4120
  breakpoint_proceeded = inf_status->breakpoint_proceeded;
4121
  proceed_to_finish = inf_status->proceed_to_finish;
4122
 
4123
  /* FIXME: Is the restore of stop_registers always needed */
4124
  memcpy (stop_registers, inf_status->stop_registers, REGISTER_BYTES);
4125
 
4126
  /* The inferior can be gone if the user types "print exit(0)"
4127
     (and perhaps other times).  */
4128
  if (target_has_execution)
4129
    write_register_bytes (0, inf_status->registers, REGISTER_BYTES);
4130
 
4131
  /* FIXME: If we are being called after stopping in a function which
4132
     is called from gdb, we should not be trying to restore the
4133
     selected frame; it just prints a spurious error message (The
4134
     message is useful, however, in detecting bugs in gdb (like if gdb
4135
     clobbers the stack)).  In fact, should we be restoring the
4136
     inferior status at all in that case?  .  */
4137
 
4138
  if (target_has_stack && inf_status->restore_stack_info)
4139
    {
4140
      struct restore_selected_frame_args fr;
4141
      fr.level = inf_status->selected_level;
4142
      fr.frame_address = inf_status->selected_frame_address;
4143
      /* The point of catch_errors is that if the stack is clobbered,
4144
         walking the stack might encounter a garbage pointer and error()
4145
         trying to dereference it.  */
4146
      if (catch_errors (restore_selected_frame, &fr,
4147
                        "Unable to restore previously selected frame:\n",
4148
                        RETURN_MASK_ERROR) == 0)
4149
        /* Error in restoring the selected frame.  Select the innermost
4150
           frame.  */
4151
 
4152
 
4153
        select_frame (get_current_frame (), 0);
4154
 
4155
    }
4156
 
4157
  free_inferior_status (inf_status);
4158
}
4159
 
4160
static void
4161
do_restore_inferior_status_cleanup (void *sts)
4162
{
4163
  restore_inferior_status (sts);
4164
}
4165
 
4166
struct cleanup *
4167
make_cleanup_restore_inferior_status (struct inferior_status *inf_status)
4168
{
4169
  return make_cleanup (do_restore_inferior_status_cleanup, inf_status);
4170
}
4171
 
4172
void
4173
discard_inferior_status (struct inferior_status *inf_status)
4174
{
4175
  /* See save_inferior_status for info on stop_bpstat. */
4176
  bpstat_clear (&inf_status->stop_bpstat);
4177
  free_inferior_status (inf_status);
4178
}
4179
 
4180
/* Oft used ptids */
4181
ptid_t null_ptid;
4182
ptid_t minus_one_ptid;
4183
 
4184
/* Create a ptid given the necessary PID, LWP, and TID components.  */
4185
 
4186
ptid_t
4187
ptid_build (int pid, long lwp, long tid)
4188
{
4189
  ptid_t ptid;
4190
 
4191
  ptid.pid = pid;
4192
  ptid.lwp = lwp;
4193
  ptid.tid = tid;
4194
  return ptid;
4195
}
4196
 
4197
/* Create a ptid from just a pid.  */
4198
 
4199
ptid_t
4200
pid_to_ptid (int pid)
4201
{
4202
  return ptid_build (pid, 0, 0);
4203
}
4204
 
4205
/* Fetch the pid (process id) component from a ptid.  */
4206
 
4207
int
4208
ptid_get_pid (ptid_t ptid)
4209
{
4210
  return ptid.pid;
4211
}
4212
 
4213
/* Fetch the lwp (lightweight process) component from a ptid.  */
4214
 
4215
long
4216
ptid_get_lwp (ptid_t ptid)
4217
{
4218
  return ptid.lwp;
4219
}
4220
 
4221
/* Fetch the tid (thread id) component from a ptid.  */
4222
 
4223
long
4224
ptid_get_tid (ptid_t ptid)
4225
{
4226
  return ptid.tid;
4227
}
4228
 
4229
/* ptid_equal() is used to test equality of two ptids.  */
4230
 
4231
int
4232
ptid_equal (ptid_t ptid1, ptid_t ptid2)
4233
{
4234
  return (ptid1.pid == ptid2.pid && ptid1.lwp == ptid2.lwp
4235
          && ptid1.tid == ptid2.tid);
4236
}
4237
 
4238
/* restore_inferior_ptid() will be used by the cleanup machinery
4239
   to restore the inferior_ptid value saved in a call to
4240
   save_inferior_ptid().  */
4241
 
4242
static void
4243
restore_inferior_ptid (void *arg)
4244
{
4245
  ptid_t *saved_ptid_ptr = arg;
4246
  inferior_ptid = *saved_ptid_ptr;
4247
  xfree (arg);
4248
}
4249
 
4250
/* Save the value of inferior_ptid so that it may be restored by a
4251
   later call to do_cleanups().  Returns the struct cleanup pointer
4252
   needed for later doing the cleanup.  */
4253
 
4254
struct cleanup *
4255
save_inferior_ptid (void)
4256
{
4257
  ptid_t *saved_ptid_ptr;
4258
 
4259
  saved_ptid_ptr = xmalloc (sizeof (ptid_t));
4260
  *saved_ptid_ptr = inferior_ptid;
4261
  return make_cleanup (restore_inferior_ptid, saved_ptid_ptr);
4262
}
4263
 
4264
 
4265
static void
4266
build_infrun (void)
4267
{
4268
  stop_registers = xmalloc (REGISTER_BYTES);
4269
}
4270
 
4271
void
4272
_initialize_infrun (void)
4273
{
4274
  register int i;
4275
  register int numsigs;
4276
  struct cmd_list_element *c;
4277
 
4278
  build_infrun ();
4279
 
4280
  register_gdbarch_swap (&stop_registers, sizeof (stop_registers), NULL);
4281
  register_gdbarch_swap (NULL, 0, build_infrun);
4282
 
4283
  add_info ("signals", signals_info,
4284
            "What debugger does when program gets various signals.\n\
4285
Specify a signal as argument to print info on that signal only.");
4286
  add_info_alias ("handle", "signals", 0);
4287
 
4288
  add_com ("handle", class_run, handle_command,
4289
           concat ("Specify how to handle a signal.\n\
4290
Args are signals and actions to apply to those signals.\n\
4291
Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
4292
from 1-15 are allowed for compatibility with old versions of GDB.\n\
4293
Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
4294
The special arg \"all\" is recognized to mean all signals except those\n\
4295
used by the debugger, typically SIGTRAP and SIGINT.\n",
4296
                   "Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
4297
\"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
4298
Stop means reenter debugger if this signal happens (implies print).\n\
4299
Print means print a message if this signal happens.\n\
4300
Pass means let program see this signal; otherwise program doesn't know.\n\
4301
Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
4302
Pass and Stop may be combined.", NULL));
4303
  if (xdb_commands)
4304
    {
4305
      add_com ("lz", class_info, signals_info,
4306
               "What debugger does when program gets various signals.\n\
4307
Specify a signal as argument to print info on that signal only.");
4308
      add_com ("z", class_run, xdb_handle_command,
4309
               concat ("Specify how to handle a signal.\n\
4310
Args are signals and actions to apply to those signals.\n\
4311
Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
4312
from 1-15 are allowed for compatibility with old versions of GDB.\n\
4313
Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
4314
The special arg \"all\" is recognized to mean all signals except those\n\
4315
used by the debugger, typically SIGTRAP and SIGINT.\n",
4316
                       "Recognized actions include \"s\" (toggles between stop and nostop), \n\
4317
\"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
4318
nopass), \"Q\" (noprint)\n\
4319
Stop means reenter debugger if this signal happens (implies print).\n\
4320
Print means print a message if this signal happens.\n\
4321
Pass means let program see this signal; otherwise program doesn't know.\n\
4322
Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
4323
Pass and Stop may be combined.", NULL));
4324
    }
4325
 
4326
  if (!dbx_commands)
4327
    stop_command = add_cmd ("stop", class_obscure, not_just_help_class_command,
4328
                            "There is no `stop' command, but you can set a hook on `stop'.\n\
4329
This allows you to set a list of commands to be run each time execution\n\
4330
of the program stops.", &cmdlist);
4331
 
4332
  numsigs = (int) TARGET_SIGNAL_LAST;
4333
  signal_stop = (unsigned char *)
4334
    xmalloc (sizeof (signal_stop[0]) * numsigs);
4335
  signal_print = (unsigned char *)
4336
    xmalloc (sizeof (signal_print[0]) * numsigs);
4337
  signal_program = (unsigned char *)
4338
    xmalloc (sizeof (signal_program[0]) * numsigs);
4339
  for (i = 0; i < numsigs; i++)
4340
    {
4341
      signal_stop[i] = 1;
4342
      signal_print[i] = 1;
4343
      signal_program[i] = 1;
4344
    }
4345
 
4346
  /* Signals caused by debugger's own actions
4347
     should not be given to the program afterwards.  */
4348
  signal_program[TARGET_SIGNAL_TRAP] = 0;
4349
  signal_program[TARGET_SIGNAL_INT] = 0;
4350
 
4351
  /* Signals that are not errors should not normally enter the debugger.  */
4352
  signal_stop[TARGET_SIGNAL_ALRM] = 0;
4353
  signal_print[TARGET_SIGNAL_ALRM] = 0;
4354
  signal_stop[TARGET_SIGNAL_VTALRM] = 0;
4355
  signal_print[TARGET_SIGNAL_VTALRM] = 0;
4356
  signal_stop[TARGET_SIGNAL_PROF] = 0;
4357
  signal_print[TARGET_SIGNAL_PROF] = 0;
4358
  signal_stop[TARGET_SIGNAL_CHLD] = 0;
4359
  signal_print[TARGET_SIGNAL_CHLD] = 0;
4360
  signal_stop[TARGET_SIGNAL_IO] = 0;
4361
  signal_print[TARGET_SIGNAL_IO] = 0;
4362
  signal_stop[TARGET_SIGNAL_POLL] = 0;
4363
  signal_print[TARGET_SIGNAL_POLL] = 0;
4364
  signal_stop[TARGET_SIGNAL_URG] = 0;
4365
  signal_print[TARGET_SIGNAL_URG] = 0;
4366
  signal_stop[TARGET_SIGNAL_WINCH] = 0;
4367
  signal_print[TARGET_SIGNAL_WINCH] = 0;
4368
 
4369
  /* These signals are used internally by user-level thread
4370
     implementations.  (See signal(5) on Solaris.)  Like the above
4371
     signals, a healthy program receives and handles them as part of
4372
     its normal operation.  */
4373
  signal_stop[TARGET_SIGNAL_LWP] = 0;
4374
  signal_print[TARGET_SIGNAL_LWP] = 0;
4375
  signal_stop[TARGET_SIGNAL_WAITING] = 0;
4376
  signal_print[TARGET_SIGNAL_WAITING] = 0;
4377
  signal_stop[TARGET_SIGNAL_CANCEL] = 0;
4378
  signal_print[TARGET_SIGNAL_CANCEL] = 0;
4379
 
4380
#ifdef SOLIB_ADD
4381
  add_show_from_set
4382
    (add_set_cmd ("stop-on-solib-events", class_support, var_zinteger,
4383
                  (char *) &stop_on_solib_events,
4384
                  "Set stopping for shared library events.\n\
4385
If nonzero, gdb will give control to the user when the dynamic linker\n\
4386
notifies gdb of shared library events.  The most common event of interest\n\
4387
to the user would be loading/unloading of a new library.\n",
4388
                  &setlist),
4389
     &showlist);
4390
#endif
4391
 
4392
  c = add_set_enum_cmd ("follow-fork-mode",
4393
                        class_run,
4394
                        follow_fork_mode_kind_names,
4395
                        &follow_fork_mode_string,
4396
/* ??rehrauer:  The "both" option is broken, by what may be a 10.20
4397
   kernel problem.  It's also not terribly useful without a GUI to
4398
   help the user drive two debuggers.  So for now, I'm disabling
4399
   the "both" option.  */
4400
/*                      "Set debugger response to a program call of fork \
4401
   or vfork.\n\
4402
   A fork or vfork creates a new process.  follow-fork-mode can be:\n\
4403
   parent  - the original process is debugged after a fork\n\
4404
   child   - the new process is debugged after a fork\n\
4405
   both    - both the parent and child are debugged after a fork\n\
4406
   ask     - the debugger will ask for one of the above choices\n\
4407
   For \"both\", another copy of the debugger will be started to follow\n\
4408
   the new child process.  The original debugger will continue to follow\n\
4409
   the original parent process.  To distinguish their prompts, the\n\
4410
   debugger copy's prompt will be changed.\n\
4411
   For \"parent\" or \"child\", the unfollowed process will run free.\n\
4412
   By default, the debugger will follow the parent process.",
4413
 */
4414
                        "Set debugger response to a program call of fork \
4415
or vfork.\n\
4416
A fork or vfork creates a new process.  follow-fork-mode can be:\n\
4417
  parent  - the original process is debugged after a fork\n\
4418
  child   - the new process is debugged after a fork\n\
4419
  ask     - the debugger will ask for one of the above choices\n\
4420
For \"parent\" or \"child\", the unfollowed process will run free.\n\
4421
By default, the debugger will follow the parent process.",
4422
                        &setlist);
4423
/*  c->function.sfunc = ; */
4424
  add_show_from_set (c, &showlist);
4425
 
4426
  c = add_set_enum_cmd ("scheduler-locking", class_run,
4427
                        scheduler_enums,        /* array of string names */
4428
                        &scheduler_mode,        /* current mode  */
4429
                        "Set mode for locking scheduler during execution.\n\
4430
off  == no locking (threads may preempt at any time)\n\
4431
on   == full locking (no thread except the current thread may run)\n\
4432
step == scheduler locked during every single-step operation.\n\
4433
        In this mode, no other thread may run during a step command.\n\
4434
        Other threads may run while stepping over a function call ('next').",
4435
                        &setlist);
4436
 
4437
  c->function.sfunc = set_schedlock_func;       /* traps on target vector */
4438
  add_show_from_set (c, &showlist);
4439
 
4440
  c = add_set_cmd ("step-mode", class_run,
4441
                   var_boolean, (char*) &step_stop_if_no_debug,
4442
"Set mode of the step operation. When set, doing a step over a\n\
4443
function without debug line information will stop at the first\n\
4444
instruction of that function. Otherwise, the function is skipped and\n\
4445
the step command stops at a different source line.",
4446
                        &setlist);
4447
  add_show_from_set (c, &showlist);
4448
 
4449
  /* ptid initializations */
4450
  null_ptid = ptid_build (0, 0, 0);
4451
  minus_one_ptid = ptid_build (-1, 0, 0);
4452
  inferior_ptid = null_ptid;
4453
  target_last_wait_ptid = minus_one_ptid;
4454
}

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