aboutsummaryrefslogtreecommitdiff
path: root/gdb/breakpoint.h
blob: 80544e4dedd698afc4a19cade6d5425f82851879 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
/* Data structures associated with breakpoints in GDB.
   Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001,
   2002, 2003, 2004, 2007, 2008 Free Software Foundation, Inc.

   This file is part of GDB.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.

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

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

#if !defined (BREAKPOINT_H)
#define BREAKPOINT_H 1

#include "frame.h"
#include "value.h"
#include "vec.h"

#include "gdb-events.h"

struct value;
struct block;

/* This is the maximum number of bytes a breakpoint instruction can take.
   Feel free to increase it.  It's just used in a few places to size
   arrays that should be independent of the target architecture.  */

#define	BREAKPOINT_MAX	16

/* Type of breakpoint. */
/* FIXME In the future, we should fold all other breakpoint-like things into
   here.  This includes:

   * single-step (for machines where we have to simulate single stepping)
   (probably, though perhaps it is better for it to look as much as
   possible like a single-step to wait_for_inferior).  */

enum bptype
  {
    bp_none = 0,		/* Eventpoint has been deleted. */
    bp_breakpoint,		/* Normal breakpoint */
    bp_hardware_breakpoint,	/* Hardware assisted breakpoint */
    bp_until,			/* used by until command */
    bp_finish,			/* used by finish command */
    bp_watchpoint,		/* Watchpoint */
    bp_hardware_watchpoint,	/* Hardware assisted watchpoint */
    bp_read_watchpoint,		/* read watchpoint, (hardware assisted) */
    bp_access_watchpoint,	/* access watchpoint, (hardware assisted) */
    bp_longjmp,			/* secret breakpoint to find longjmp() */
    bp_longjmp_resume,		/* secret breakpoint to escape longjmp() */

    /* Used by wait_for_inferior for stepping over subroutine calls, for
       stepping over signal handlers, and for skipping prologues.  */
    bp_step_resume,

    /* Used to detect when a watchpoint expression has gone out of
       scope.  These breakpoints are usually not visible to the user.

       This breakpoint has some interesting properties:

       1) There's always a 1:1 mapping between watchpoints
       on local variables and watchpoint_scope breakpoints.

       2) It automatically deletes itself and the watchpoint it's
       associated with when hit.

       3) It can never be disabled.  */
    bp_watchpoint_scope,

    /* The breakpoint at the end of a call dummy.  */
    /* FIXME: What if the function we are calling longjmp()s out of the
       call, or the user gets out with the "return" command?  We currently
       have no way of cleaning up the breakpoint in these (obscure) situations.
       (Probably can solve this by noticing longjmp, "return", etc., it's
       similar to noticing when a watchpoint on a local variable goes out
       of scope (with hardware support for watchpoints)).  */
    bp_call_dummy,

    /* Some dynamic linkers (HP, maybe Solaris) can arrange for special
       code in the inferior to run when significant events occur in the
       dynamic linker (for example a library is loaded or unloaded).

       By placing a breakpoint in this magic code GDB will get control
       when these significant events occur.  GDB can then re-examine
       the dynamic linker's data structures to discover any newly loaded
       dynamic libraries.  */
    bp_shlib_event,

    /* Some multi-threaded systems can arrange for a location in the 
       inferior to be executed when certain thread-related events occur
       (such as thread creation or thread death).

       By placing a breakpoint at one of these locations, GDB will get
       control when these events occur.  GDB can then update its thread
       lists etc.  */

    bp_thread_event,

    /* On the same principal, an overlay manager can arrange to call a
       magic location in the inferior whenever there is an interesting
       change in overlay status.  GDB can update its overlay tables
       and fiddle with breakpoints in overlays when this breakpoint 
       is hit.  */

    bp_overlay_event, 

    /* These breakpoints are used to implement the "catch load" command
       on platforms whose dynamic linkers support such functionality.  */
    bp_catch_load,

    /* These breakpoints are used to implement the "catch unload" command
       on platforms whose dynamic linkers support such functionality.  */
    bp_catch_unload,

    /* These are not really breakpoints, but are catchpoints that
       implement the "catch fork", "catch vfork" and "catch exec" commands
       on platforms whose kernel support such functionality.  (I.e.,
       kernels which can raise an event when a fork or exec occurs, as
       opposed to the debugger setting breakpoints on functions named
       "fork" or "exec".) */
    bp_catch_fork,
    bp_catch_vfork,
    bp_catch_exec,
  };

/* States of enablement of breakpoint. */

enum enable_state
  {
    bp_disabled,	/* The eventpoint is inactive, and cannot trigger. */
    bp_enabled,		/* The eventpoint is active, and can trigger. */
    bp_call_disabled,	/* The eventpoint has been disabled while a call 
			   into the inferior is "in flight", because some 
			   eventpoints interfere with the implementation of 
			   a call on some targets.  The eventpoint will be 
			   automatically enabled and reset when the call 
			   "lands" (either completes, or stops at another 
			   eventpoint). */
    bp_permanent	/* There is a breakpoint instruction hard-wired into
			   the target's code.  Don't try to write another
			   breakpoint instruction on top of it, or restore
			   its value.  Step over it using the architecture's
			   SKIP_INSN macro.  */
  };


/* Disposition of breakpoint.  Ie: what to do after hitting it. */

enum bpdisp
  {
    disp_del,			/* Delete it */
    disp_del_at_next_stop,	/* Delete at next stop, whether hit or not */
    disp_disable,		/* Disable it */
    disp_donttouch		/* Leave it alone */
  };

enum target_hw_bp_type
  {
    hw_write   = 0, 		/* Common  HW watchpoint */
    hw_read    = 1, 		/* Read    HW watchpoint */
    hw_access  = 2, 		/* Access  HW watchpoint */
    hw_execute = 3		/* Execute HW breakpoint */
  };


/* Information used by targets to insert and remove breakpoints.  */

struct bp_target_info
{
  /* Address at which the breakpoint was placed.  This is normally the
     same as ADDRESS from the bp_location, except when adjustment
     happens in gdbarch_breakpoint_from_pc.  The most common form of
     adjustment is stripping an alternate ISA marker from the PC which
     is used to determine the type of breakpoint to insert.  */
  CORE_ADDR placed_address;

  /* If the breakpoint lives in memory and reading that memory would
     give back the breakpoint, instead of the original contents, then
     the original contents are cached here.  Only SHADOW_LEN bytes of
     this buffer are valid, and only when the breakpoint is inserted.  */
  gdb_byte shadow_contents[BREAKPOINT_MAX];

  /* The length of the data cached in SHADOW_CONTENTS.  */
  int shadow_len;

  /* The size of the placed breakpoint, according to
     gdbarch_breakpoint_from_pc, when the breakpoint was inserted.  This is
     generally the same as SHADOW_LEN, unless we did not need
     to read from the target to implement the memory breakpoint
     (e.g. if a remote stub handled the details).  We may still
     need the size to remove the breakpoint safely.  */
  int placed_size;
};

/* GDB maintains two types of information about each breakpoint (or
   watchpoint, or other related event).  The first type corresponds
   to struct breakpoint; this is a relatively high-level structure
   which contains the source location(s), stopping conditions, user
   commands to execute when the breakpoint is hit, and so forth.

   The second type of information corresponds to struct bp_location.
   Each breakpoint has one or (eventually) more locations associated
   with it, which represent target-specific and machine-specific
   mechanisms for stopping the program.  For instance, a watchpoint
   expression may require multiple hardware watchpoints in order to
   catch all changes in the value of the expression being watched.  */

enum bp_loc_type
{
  bp_loc_software_breakpoint,
  bp_loc_hardware_breakpoint,
  bp_loc_hardware_watchpoint,
  bp_loc_other			/* Miscellaneous...  */
};

struct bp_location
{
  /* Chain pointer to the next breakpoint location for
     the same parent breakpoint.  */
  struct bp_location *next;

  /* Pointer to the next breakpoint location, in a global
     list of all breakpoint locations.  */
  struct bp_location *global_next;
 
  /* Type of this breakpoint location.  */
  enum bp_loc_type loc_type;

  /* Each breakpoint location must belong to exactly one higher-level
     breakpoint.  This and the DUPLICATE flag are more straightforward
     than reference counting.  */
  struct breakpoint *owner;

  /* Conditional.  Break only if this expression's value is nonzero.  
     Unlike string form of condition, which is associated with breakpoint,
     this is associated with location, since if breakpoint has several
     locations,  the evaluation of expression can be different for
     different locations.  */
  struct expression *cond;

  /* This location's address is in an unloaded solib, and so this
     location should not be inserted.  It will be automatically
     enabled when that solib is loaded.  */
  char shlib_disabled; 

  /* Is this particular location enabled.  */
  char enabled;
  
  /* Nonzero if this breakpoint is now inserted.  */
  char inserted;

  /* Nonzero if this is not the first breakpoint in the list
     for the given address.  */
  char duplicate;

  /* If we someday support real thread-specific breakpoints, then
     the breakpoint location will need a thread identifier.  */

  /* Data for specific breakpoint types.  These could be a union, but
     simplicity is more important than memory usage for breakpoints.  */

  /* Note that zero is a perfectly valid code address on some platforms
     (for example, the mn10200 (OBSOLETE) and mn10300 simulators).  NULL
     is not a special value for this field.  Valid for all types except
     bp_loc_other.  */
  CORE_ADDR address;

  /* For hardware watchpoints, the size of data ad ADDRESS being watches.  */
  int length;

  /* Type of hardware watchpoint. */
  enum target_hw_bp_type watchpoint_type;

  /* For any breakpoint type with an address, this is the BFD section
     associated with the address.  Used primarily for overlay debugging.  */
  asection *section;

  /* Address at which breakpoint was requested, either by the user or
     by GDB for internal breakpoints.  This will usually be the same
     as ``address'' (above) except for cases in which
     ADJUST_BREAKPOINT_ADDRESS has computed a different address at
     which to place the breakpoint in order to comply with a
     processor's architectual constraints.  */
  CORE_ADDR requested_address;

  char *function_name;

  /* Details of the placed breakpoint, when inserted.  */
  struct bp_target_info target_info;

  /* Similarly, for the breakpoint at an overlay's LMA, if necessary.  */
  struct bp_target_info overlay_target_info;
};

/* This structure is a collection of function pointers that, if available,
   will be called instead of the performing the default action for this
   bptype.  */

struct breakpoint_ops 
{
  /* The normal print routine for this breakpoint, called when we
     hit it.  */
  enum print_stop_action (*print_it) (struct breakpoint *);

  /* Display information about this breakpoint, for "info breakpoints".  */
  void (*print_one) (struct breakpoint *, CORE_ADDR *);

  /* Display information about this breakpoint after setting it (roughly
     speaking; this is called from "mention").  */
  void (*print_mention) (struct breakpoint *);
};

enum watchpoint_triggered
{
  /* This watchpoint definitely did not trigger.  */
  watch_triggered_no = 0,

  /* Some hardware watchpoint triggered, and it might have been this
     one, but we do not know which it was.  */
  watch_triggered_unknown,

  /* This hardware watchpoint definitely did trigger.  */
  watch_triggered_yes  
};

typedef struct bp_location *bp_location_p;
DEF_VEC_P(bp_location_p);

/* Note that the ->silent field is not currently used by any commands
   (though the code is in there if it was to be, and set_raw_breakpoint
   does set it to 0).  I implemented it because I thought it would be
   useful for a hack I had to put in; I'm going to leave it in because
   I can see how there might be times when it would indeed be useful */

/* This is for a breakpoint or a watchpoint.  */

struct breakpoint
  {
    struct breakpoint *next;
    /* Type of breakpoint. */
    enum bptype type;
    /* Zero means disabled; remember the info but don't break here.  */
    enum enable_state enable_state;
    /* What to do with this breakpoint after we hit it. */
    enum bpdisp disposition;
    /* Number assigned to distinguish breakpoints.  */
    int number;

    /* Location(s) associated with this high-level breakpoint.  */
    struct bp_location *loc;

    /* Line number of this address.  */

    int line_number;

    /* Source file name of this address.  */

    char *source_file;

    /* Non-zero means a silent breakpoint (don't print frame info
       if we stop here). */
    unsigned char silent;
    /* Number of stops at this breakpoint that should
       be continued automatically before really stopping.  */
    int ignore_count;
    /* Chain of command lines to execute when this breakpoint is hit.  */
    struct command_line *commands;
    /* Stack depth (address of frame).  If nonzero, break only if fp
       equals this.  */
    struct frame_id frame_id;

    /* String we used to set the breakpoint (malloc'd).  */
    char *addr_string;
    /* Language we used to set the breakpoint.  */
    enum language language;
    /* Input radix we used to set the breakpoint.  */
    int input_radix;
    /* String form of the breakpoint condition (malloc'd), or NULL if there
       is no condition.  */
    char *cond_string;
    /* String form of exp (malloc'd), or NULL if none.  */
    char *exp_string;

    /* The expression we are watching, or NULL if not a watchpoint.  */
    struct expression *exp;
    /* The largest block within which it is valid, or NULL if it is
       valid anywhere (e.g. consists just of global symbols).  */
    struct block *exp_valid_block;
    /* Value of the watchpoint the last time we checked it, or NULL
       when we do not know the value yet or the value was not
       readable.  VAL is never lazy.  */
    struct value *val;
    /* Nonzero if VAL is valid.  If VAL_VALID is set but VAL is NULL,
       then an error occurred reading the value.  */
    int val_valid;

    /* Holds the address of the related watchpoint_scope breakpoint
       when using watchpoints on local variables (might the concept
       of a related breakpoint be useful elsewhere, if not just call
       it the watchpoint_scope breakpoint or something like that. FIXME).  */
    struct breakpoint *related_breakpoint;

    /* Holds the frame address which identifies the frame this
       watchpoint should be evaluated in, or `null' if the watchpoint
       should be evaluated on the outermost frame.  */
    struct frame_id watchpoint_frame;

    /* For hardware watchpoints, the triggered status according to the
       hardware.  */
    enum watchpoint_triggered watchpoint_triggered;

    /* Thread number for thread-specific breakpoint, or -1 if don't care */
    int thread;

    /* Count of the number of times this breakpoint was taken, dumped
       with the info, but not used for anything else.  Useful for
       seeing how many times you hit a break prior to the program
       aborting, so you can back up to just before the abort.  */
    int hit_count;

    /* Filename of a dynamically-linked library (dll), used for
       bp_catch_load and bp_catch_unload (malloc'd), or NULL if any
       library is significant.  */
    char *dll_pathname;

    /* Filename of a dll whose state change (e.g., load or unload)
       triggered this catchpoint.  This field is only valid immediately
       after this catchpoint has triggered.  */
    char *triggered_dll_pathname;

    /* Process id of a child process whose forking triggered this
       catchpoint.  This field is only valid immediately after this
       catchpoint has triggered.  */
    int forked_inferior_pid;

    /* Filename of a program whose exec triggered this catchpoint.
       This field is only valid immediately after this catchpoint has
       triggered.  */
    char *exec_pathname;

    /* Methods associated with this breakpoint.  */
    struct breakpoint_ops *ops;

    /* Is breakpoint's condition not yet parsed because we found
       no location initially so had no context to parse
       the condition in.  */
    int condition_not_parsed;
  };

typedef struct breakpoint *breakpoint_p;
DEF_VEC_P(breakpoint_p);

/* The following stuff is an abstract data type "bpstat" ("breakpoint
   status").  This provides the ability to determine whether we have
   stopped at a breakpoint, and what we should do about it.  */

typedef struct bpstats *bpstat;

/* Frees any storage that is part of a bpstat.
   Does not walk the 'next' chain.  */
extern void bpstat_free (bpstat);

/* Clears a chain of bpstat, freeing storage
   of each.  */
extern void bpstat_clear (bpstat *);

/* Return a copy of a bpstat.  Like "bs1 = bs2" but all storage that
   is part of the bpstat is copied as well.  */
extern bpstat bpstat_copy (bpstat);

extern bpstat bpstat_stop_status (CORE_ADDR pc, ptid_t ptid);

/* This bpstat_what stuff tells wait_for_inferior what to do with a
   breakpoint (a challenging task).  */

enum bpstat_what_main_action
  {
    /* Perform various other tests; that is, this bpstat does not
       say to perform any action (e.g. failed watchpoint and nothing
       else).  */
    BPSTAT_WHAT_KEEP_CHECKING,

    /* Rather than distinguish between noisy and silent stops here, it
       might be cleaner to have bpstat_print make that decision (also
       taking into account stop_print_frame and source_only).  But the
       implications are a bit scary (interaction with auto-displays, etc.),
       so I won't try it.  */

    /* Stop silently.  */
    BPSTAT_WHAT_STOP_SILENT,

    /* Stop and print.  */
    BPSTAT_WHAT_STOP_NOISY,

    /* Remove breakpoints, single step once, then put them back in and
       go back to what we were doing.  It's possible that this should be
       removed from the main_action and put into a separate field, to more
       cleanly handle BPSTAT_WHAT_CLEAR_LONGJMP_RESUME_SINGLE.  */
    BPSTAT_WHAT_SINGLE,

    /* Set longjmp_resume breakpoint, remove all other breakpoints,
       and continue.  The "remove all other breakpoints" part is required
       if we are also stepping over another breakpoint as well as doing
       the longjmp handling.  */
    BPSTAT_WHAT_SET_LONGJMP_RESUME,

    /* Clear longjmp_resume breakpoint, then handle as
       BPSTAT_WHAT_KEEP_CHECKING.  */
    BPSTAT_WHAT_CLEAR_LONGJMP_RESUME,

    /* Clear step resume breakpoint, and keep checking.  */
    BPSTAT_WHAT_STEP_RESUME,

    /* Check the dynamic linker's data structures for new libraries, then
       keep checking.  */
    BPSTAT_WHAT_CHECK_SHLIBS,

    /* Check the dynamic linker's data structures for new libraries, then
       resume out of the dynamic linker's callback, stop and print.  */
    BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK,

    /* This is just used to keep track of how many enums there are.  */
    BPSTAT_WHAT_LAST
  };

struct bpstat_what
  {
    enum bpstat_what_main_action main_action;

    /* Did we hit a call dummy breakpoint?  This only goes with a main_action
       of BPSTAT_WHAT_STOP_SILENT or BPSTAT_WHAT_STOP_NOISY (the concept of
       continuing from a call dummy without popping the frame is not a
       useful one).  */
    int call_dummy;
  };

/* The possible return values for print_bpstat, print_it_normal,
   print_it_done, print_it_noop. */
enum print_stop_action
  {
    PRINT_UNKNOWN = -1,
    PRINT_SRC_AND_LOC,
    PRINT_SRC_ONLY,
    PRINT_NOTHING
  };

/* Tell what to do about this bpstat.  */
struct bpstat_what bpstat_what (bpstat);

/* Find the bpstat associated with a breakpoint.  NULL otherwise. */
bpstat bpstat_find_breakpoint (bpstat, struct breakpoint *);

/* Find a step_resume breakpoint associated with this bpstat.
   (If there are multiple step_resume bp's on the list, this function
   will arbitrarily pick one.)

   It is an error to use this function if BPSTAT doesn't contain a
   step_resume breakpoint.

   See wait_for_inferior's use of this function.
 */
extern struct breakpoint *bpstat_find_step_resume_breakpoint (bpstat);

/* Nonzero if a signal that we got in wait() was due to circumstances
   explained by the BS.  */
/* Currently that is true if we have hit a breakpoint, or if there is
   a watchpoint enabled.  */
#define bpstat_explains_signal(bs) ((bs) != NULL)

/* Nonzero if we should step constantly (e.g. watchpoints on machines
   without hardware support).  This isn't related to a specific bpstat,
   just to things like whether watchpoints are set.  */
extern int bpstat_should_step (void);

/* Print a message indicating what happened.  Returns nonzero to
   say that only the source line should be printed after this (zero
   return means print the frame as well as the source line).  */
extern enum print_stop_action bpstat_print (bpstat);

/* Put in *NUM the breakpoint number of the first breakpoint we are stopped
   at.  *BSP upon return is a bpstat which points to the remaining
   breakpoints stopped at (but which is not guaranteed to be good for
   anything but further calls to bpstat_num).
   Return 0 if passed a bpstat which does not indicate any breakpoints.
   Return -1 if stopped at a breakpoint that has been deleted since
   we set it.
   Return 1 otherwise.  */
extern int bpstat_num (bpstat *, int *);

/* Perform actions associated with having stopped at *BSP.  Actually, we just
   use this for breakpoint commands.  Perhaps other actions will go here
   later, but this is executed at a late time (from the command loop).  */
extern void bpstat_do_actions (bpstat *);

/* Modify BS so that the actions will not be performed.  */
extern void bpstat_clear_actions (bpstat);

/* Given a bpstat that records zero or more triggered eventpoints, this
   function returns another bpstat which contains only the catchpoints
   on that first list, if any.
 */
extern void bpstat_get_triggered_catchpoints (bpstat, bpstat *);

/* Implementation:  */

/* Values used to tell the printing routine how to behave for this bpstat. */
enum bp_print_how
  {
    /* This is used when we want to do a normal printing of the reason
       for stopping. The output will depend on the type of eventpoint
       we are dealing with. This is the default value, most commonly
       used. */
    print_it_normal,
    /* This is used when nothing should be printed for this bpstat entry.  */
    print_it_noop,
    /* This is used when everything which needs to be printed has
       already been printed.  But we still want to print the frame.  */
    print_it_done
  };

struct bpstats
  {
    /* Linked list because there can be two breakpoints at the same
       place, and a bpstat reflects the fact that both have been hit.  */
    bpstat next;
    /* Breakpoint that we are at.  */
    const struct bp_location *breakpoint_at;
    /* Commands left to be done.  */
    struct command_line *commands;
    /* Old value associated with a watchpoint.  */
    struct value *old_val;

    /* Nonzero if this breakpoint tells us to print the frame.  */
    char print;

    /* Nonzero if this breakpoint tells us to stop.  */
    char stop;

    /* Tell bpstat_print and print_bp_stop_message how to print stuff
       associated with this element of the bpstat chain.  */
    enum bp_print_how print_it;
  };

enum inf_context
  {
    inf_starting,
    inf_running,
    inf_exited
  };

/* The possible return values for breakpoint_here_p.
   We guarantee that zero always means "no breakpoint here".  */
enum breakpoint_here
  {
    no_breakpoint_here = 0,
    ordinary_breakpoint_here,
    permanent_breakpoint_here
  };


/* Prototypes for breakpoint-related functions.  */

extern enum breakpoint_here breakpoint_here_p (CORE_ADDR);

extern int breakpoint_inserted_here_p (CORE_ADDR);

extern int regular_breakpoint_inserted_here_p (CORE_ADDR);

extern int software_breakpoint_inserted_here_p (CORE_ADDR);

extern int breakpoint_thread_match (CORE_ADDR, ptid_t);

extern void until_break_command (char *, int, int);

extern void breakpoint_re_set (void);

extern void breakpoint_re_set_thread (struct breakpoint *);

extern struct breakpoint *set_momentary_breakpoint
  (struct symtab_and_line, struct frame_id, enum bptype);

extern struct breakpoint *set_momentary_breakpoint_at_pc
  (CORE_ADDR pc, enum bptype type);

extern void set_ignore_count (int, int, int);

extern void set_default_breakpoint (int, CORE_ADDR, struct symtab *, int);

extern void breakpoint_init_inferior (enum inf_context);

extern struct cleanup *make_cleanup_delete_breakpoint (struct breakpoint *);

extern void delete_breakpoint (struct breakpoint *);

extern void breakpoint_auto_delete (bpstat);

extern void breakpoint_clear_ignore_counts (void);

extern void break_command (char *, int);

extern void hbreak_command_wrapper (char *, int);
extern void thbreak_command_wrapper (char *, int);
extern void rbreak_command_wrapper (char *, int);
extern void watch_command_wrapper (char *, int);
extern void awatch_command_wrapper (char *, int);
extern void rwatch_command_wrapper (char *, int);
extern void tbreak_command (char *, int);

extern void set_breakpoint (char *address, char *condition,
			    int hardwareflag, int tempflag,
			    int thread, int ignore_count,
			    int pending);

extern void insert_breakpoints (void);

extern int remove_breakpoints (void);

/* This function can be used to physically insert eventpoints from the
   specified traced inferior process, without modifying the breakpoint
   package's state.  This can be useful for those targets which support
   following the processes of a fork() or vfork() system call, when both
   of the resulting two processes are to be followed.  */
extern int reattach_breakpoints (int);

/* This function can be used to update the breakpoint package's state
   after an exec() system call has been executed.

   This function causes the following:

   - All eventpoints are marked "not inserted".
   - All eventpoints with a symbolic address are reset such that
   the symbolic address must be reevaluated before the eventpoints
   can be reinserted.
   - The solib breakpoints are explicitly removed from the breakpoint
   list.
   - A step-resume breakpoint, if any, is explicitly removed from the
   breakpoint list.
   - All eventpoints without a symbolic address are removed from the
   breakpoint list. */
extern void update_breakpoints_after_exec (void);

/* This function can be used to physically remove hardware breakpoints
   and watchpoints from the specified traced inferior process, without
   modifying the breakpoint package's state.  This can be useful for
   those targets which support following the processes of a fork() or
   vfork() system call, when one of the resulting two processes is to
   be detached and allowed to run free.

   It is an error to use this function on the process whose id is
   inferior_ptid.  */
extern int detach_breakpoints (int);

extern void set_longjmp_breakpoint (void);
extern void delete_longjmp_breakpoint (int thread);

extern void enable_overlay_breakpoints (void);
extern void disable_overlay_breakpoints (void);

/* These functions respectively disable or reenable all currently
   enabled watchpoints.  When disabled, the watchpoints are marked
   call_disabled.  When reenabled, they are marked enabled.

   The intended client of these functions is call_function_by_hand.

   The inferior must be stopped, and all breakpoints removed, when
   these functions are used.

   The need for these functions is that on some targets (e.g., HP-UX),
   gdb is unable to unwind through the dummy frame that is pushed as
   part of the implementation of a call command.  Watchpoints can
   cause the inferior to stop in places where this frame is visible,
   and that can cause execution control to become very confused.

   Note that if a user sets breakpoints in an interactively called
   function, the call_disabled watchpoints will have been reenabled
   when the first such breakpoint is reached.  However, on targets
   that are unable to unwind through the call dummy frame, watches
   of stack-based storage may then be deleted, because gdb will
   believe that their watched storage is out of scope.  (Sigh.) */
extern void disable_watchpoints_before_interactive_call_start (void);

extern void enable_watchpoints_after_interactive_call_stop (void);

/* For script interpreters that need to define breakpoint commands
   after they've already read the commands into a struct command_line.  */
extern enum command_control_type commands_from_control_command
  (char *arg, struct command_line *cmd);

extern void clear_breakpoint_hit_counts (void);

extern int get_number (char **);

extern int get_number_or_range (char **);

/* The following are for displays, which aren't really breakpoints, but
   here is as good a place as any for them.  */

extern void disable_current_display (void);

extern void do_displays (void);

extern void disable_display (int);

extern void clear_displays (void);

extern void disable_breakpoint (struct breakpoint *);

extern void enable_breakpoint (struct breakpoint *);

extern void make_breakpoint_permanent (struct breakpoint *);

extern struct breakpoint *create_solib_event_breakpoint (CORE_ADDR);

extern struct breakpoint *create_thread_event_breakpoint (CORE_ADDR);

extern void remove_solib_event_breakpoints (void);

extern void remove_thread_event_breakpoints (void);

extern void disable_breakpoints_in_shlibs (void);

/* This function returns TRUE if ep is a catchpoint. */
extern int ep_is_catchpoint (struct breakpoint *);

/* This function returns TRUE if ep is a catchpoint of a
   shared library (aka dynamically-linked library) event,
   such as a library load or unload. */
extern int ep_is_shlib_catchpoint (struct breakpoint *);

/* Enable breakpoints and delete when hit.  Called with ARG == NULL
   deletes all breakpoints. */
extern void delete_command (char *arg, int from_tty);

/* Pull all H/W watchpoints from the target. Return non-zero if the
   remove fails. */
extern int remove_hw_watchpoints (void);

/* Manage a software single step breakpoint (or two).  Insert may be called
   twice before remove is called.  */
extern void insert_single_step_breakpoint (CORE_ADDR);
extern void remove_single_step_breakpoints (void);

/* Manage manual breakpoints, separate from the normal chain of
   breakpoints.  These functions are used in murky target-specific
   ways.  Please do not add more uses!  */
extern void *deprecated_insert_raw_breakpoint (CORE_ADDR);
extern int deprecated_remove_raw_breakpoint (void *);

/* Check if any hardware watchpoints have triggered, according to the
   target.  */
int watchpoints_triggered (struct target_waitstatus *);

/* Update BUF, which is LEN bytes read from the target address MEMADDR,
   by replacing any memory breakpoints with their shadowed contents.  */
void breakpoint_restore_shadows (gdb_byte *buf, ULONGEST memaddr, 
				 LONGEST len);

extern int breakpoints_always_inserted_mode (void);

#endif /* !defined (BREAKPOINT_H) */