xref: /dragonfly/contrib/gdb-7/gdb/breakpoint.h (revision 2b23d27f)
1 /* Data structures associated with breakpoints in GDB.
2    Copyright (C) 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000, 2001,
3    2002, 2003, 2004, 2007, 2008, 2009, 2010 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 3 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, see <http://www.gnu.org/licenses/>.  */
19 
20 #if !defined (BREAKPOINT_H)
21 #define BREAKPOINT_H 1
22 
23 #include "frame.h"
24 #include "value.h"
25 #include "vec.h"
26 
27 struct value;
28 struct block;
29 
30 /* This is the maximum number of bytes a breakpoint instruction can take.
31    Feel free to increase it.  It's just used in a few places to size
32    arrays that should be independent of the target architecture.  */
33 
34 #define	BREAKPOINT_MAX	16
35 
36 
37 /* Type of breakpoint.  */
38 /* FIXME In the future, we should fold all other breakpoint-like things into
39    here.  This includes:
40 
41    * single-step (for machines where we have to simulate single stepping)
42    (probably, though perhaps it is better for it to look as much as
43    possible like a single-step to wait_for_inferior).  */
44 
45 enum bptype
46   {
47     bp_none = 0,		/* Eventpoint has been deleted. */
48     bp_breakpoint,		/* Normal breakpoint */
49     bp_hardware_breakpoint,	/* Hardware assisted breakpoint */
50     bp_until,			/* used by until command */
51     bp_finish,			/* used by finish command */
52     bp_watchpoint,		/* Watchpoint */
53     bp_hardware_watchpoint,	/* Hardware assisted watchpoint */
54     bp_read_watchpoint,		/* read watchpoint, (hardware assisted) */
55     bp_access_watchpoint,	/* access watchpoint, (hardware assisted) */
56     bp_longjmp,			/* secret breakpoint to find longjmp() */
57     bp_longjmp_resume,		/* secret breakpoint to escape longjmp() */
58 
59     /* Used by wait_for_inferior for stepping over subroutine calls, for
60        stepping over signal handlers, and for skipping prologues.  */
61     bp_step_resume,
62 
63     /* Used to detect when a watchpoint expression has gone out of
64        scope.  These breakpoints are usually not visible to the user.
65 
66        This breakpoint has some interesting properties:
67 
68        1) There's always a 1:1 mapping between watchpoints
69        on local variables and watchpoint_scope breakpoints.
70 
71        2) It automatically deletes itself and the watchpoint it's
72        associated with when hit.
73 
74        3) It can never be disabled.  */
75     bp_watchpoint_scope,
76 
77     /* The breakpoint at the end of a call dummy.  */
78     /* FIXME: What if the function we are calling longjmp()s out of the
79        call, or the user gets out with the "return" command?  We currently
80        have no way of cleaning up the breakpoint in these (obscure) situations.
81        (Probably can solve this by noticing longjmp, "return", etc., it's
82        similar to noticing when a watchpoint on a local variable goes out
83        of scope (with hardware support for watchpoints)).  */
84     bp_call_dummy,
85 
86     /* A breakpoint set on std::terminate, that is used to catch
87        otherwise uncaught exceptions thrown during an inferior call.  */
88     bp_std_terminate,
89 
90     /* Some dynamic linkers (HP, maybe Solaris) can arrange for special
91        code in the inferior to run when significant events occur in the
92        dynamic linker (for example a library is loaded or unloaded).
93 
94        By placing a breakpoint in this magic code GDB will get control
95        when these significant events occur.  GDB can then re-examine
96        the dynamic linker's data structures to discover any newly loaded
97        dynamic libraries.  */
98     bp_shlib_event,
99 
100     /* Some multi-threaded systems can arrange for a location in the
101        inferior to be executed when certain thread-related events occur
102        (such as thread creation or thread death).
103 
104        By placing a breakpoint at one of these locations, GDB will get
105        control when these events occur.  GDB can then update its thread
106        lists etc.  */
107 
108     bp_thread_event,
109 
110     /* On the same principal, an overlay manager can arrange to call a
111        magic location in the inferior whenever there is an interesting
112        change in overlay status.  GDB can update its overlay tables
113        and fiddle with breakpoints in overlays when this breakpoint
114        is hit.  */
115 
116     bp_overlay_event,
117 
118     /* Master copies of longjmp breakpoints.  These are always installed
119        as soon as an objfile containing longjmp is loaded, but they are
120        always disabled.  While necessary, temporary clones of bp_longjmp
121        type will be created and enabled.  */
122 
123     bp_longjmp_master,
124 
125     /* Master copies of std::terminate breakpoints.  */
126     bp_std_terminate_master,
127 
128     bp_catchpoint,
129 
130     bp_tracepoint,
131     bp_fast_tracepoint,
132     bp_static_tracepoint,
133 
134     /* Event for JIT compiled code generation or deletion.  */
135     bp_jit_event,
136   };
137 
138 /* States of enablement of breakpoint. */
139 
140 enum enable_state
141   {
142     bp_disabled,	/* The eventpoint is inactive, and cannot trigger. */
143     bp_enabled,		/* The eventpoint is active, and can trigger. */
144     bp_call_disabled,	/* The eventpoint has been disabled while a call
145 			   into the inferior is "in flight", because some
146 			   eventpoints interfere with the implementation of
147 			   a call on some targets.  The eventpoint will be
148 			   automatically enabled and reset when the call
149 			   "lands" (either completes, or stops at another
150 			   eventpoint). */
151     bp_startup_disabled,/* The eventpoint has been disabled during inferior
152 			   startup.  This is necessary on some targets where
153 			   the main executable will get relocated during
154 			   startup, making breakpoint addresses invalid.
155 			   The eventpoint will be automatically enabled and
156 			   reset once inferior startup is complete.  */
157     bp_permanent	/* There is a breakpoint instruction hard-wired into
158 			   the target's code.  Don't try to write another
159 			   breakpoint instruction on top of it, or restore
160 			   its value.  Step over it using the architecture's
161 			   SKIP_INSN macro.  */
162   };
163 
164 
165 /* Disposition of breakpoint.  Ie: what to do after hitting it. */
166 
167 enum bpdisp
168   {
169     disp_del,			/* Delete it */
170     disp_del_at_next_stop,	/* Delete at next stop, whether hit or not */
171     disp_disable,		/* Disable it */
172     disp_donttouch		/* Leave it alone */
173   };
174 
175 enum target_hw_bp_type
176   {
177     hw_write   = 0, 		/* Common  HW watchpoint */
178     hw_read    = 1, 		/* Read    HW watchpoint */
179     hw_access  = 2, 		/* Access  HW watchpoint */
180     hw_execute = 3		/* Execute HW breakpoint */
181   };
182 
183 
184 /* Information used by targets to insert and remove breakpoints.  */
185 
186 struct bp_target_info
187 {
188   /* Address space at which the breakpoint was placed.  */
189   struct address_space *placed_address_space;
190 
191   /* Address at which the breakpoint was placed.  This is normally the
192      same as ADDRESS from the bp_location, except when adjustment
193      happens in gdbarch_breakpoint_from_pc.  The most common form of
194      adjustment is stripping an alternate ISA marker from the PC which
195      is used to determine the type of breakpoint to insert.  */
196   CORE_ADDR placed_address;
197 
198   /* If the breakpoint lives in memory and reading that memory would
199      give back the breakpoint, instead of the original contents, then
200      the original contents are cached here.  Only SHADOW_LEN bytes of
201      this buffer are valid, and only when the breakpoint is inserted.  */
202   gdb_byte shadow_contents[BREAKPOINT_MAX];
203 
204   /* The length of the data cached in SHADOW_CONTENTS.  */
205   int shadow_len;
206 
207   /* The size of the placed breakpoint, according to
208      gdbarch_breakpoint_from_pc, when the breakpoint was inserted.  This is
209      generally the same as SHADOW_LEN, unless we did not need
210      to read from the target to implement the memory breakpoint
211      (e.g. if a remote stub handled the details).  We may still
212      need the size to remove the breakpoint safely.  */
213   int placed_size;
214 };
215 
216 /* GDB maintains two types of information about each breakpoint (or
217    watchpoint, or other related event).  The first type corresponds
218    to struct breakpoint; this is a relatively high-level structure
219    which contains the source location(s), stopping conditions, user
220    commands to execute when the breakpoint is hit, and so forth.
221 
222    The second type of information corresponds to struct bp_location.
223    Each breakpoint has one or (eventually) more locations associated
224    with it, which represent target-specific and machine-specific
225    mechanisms for stopping the program.  For instance, a watchpoint
226    expression may require multiple hardware watchpoints in order to
227    catch all changes in the value of the expression being watched.  */
228 
229 enum bp_loc_type
230 {
231   bp_loc_software_breakpoint,
232   bp_loc_hardware_breakpoint,
233   bp_loc_hardware_watchpoint,
234   bp_loc_other			/* Miscellaneous...  */
235 };
236 
237 struct bp_location
238 {
239   /* Chain pointer to the next breakpoint location for
240      the same parent breakpoint.  */
241   struct bp_location *next;
242 
243   /* Type of this breakpoint location.  */
244   enum bp_loc_type loc_type;
245 
246   /* Each breakpoint location must belong to exactly one higher-level
247      breakpoint.  This and the DUPLICATE flag are more straightforward
248      than reference counting.  This pointer is NULL iff this bp_location is in
249      (and therefore only in) moribund_locations.  */
250   struct breakpoint *owner;
251 
252   /* Conditional.  Break only if this expression's value is nonzero.
253      Unlike string form of condition, which is associated with
254      breakpoint, this is associated with location, since if breakpoint
255      has several locations, the evaluation of expression can be
256      different for different locations.  Only valid for real
257      breakpoints; a watchpoint's conditional expression is stored in
258      the owner breakpoint object.  */
259   struct expression *cond;
260 
261   /* This location's address is in an unloaded solib, and so this
262      location should not be inserted.  It will be automatically
263      enabled when that solib is loaded.  */
264   char shlib_disabled;
265 
266   /* Is this particular location enabled.  */
267   char enabled;
268 
269   /* Nonzero if this breakpoint is now inserted.  */
270   char inserted;
271 
272   /* Nonzero if this is not the first breakpoint in the list
273      for the given address.  */
274   char duplicate;
275 
276   /* If we someday support real thread-specific breakpoints, then
277      the breakpoint location will need a thread identifier.  */
278 
279   /* Data for specific breakpoint types.  These could be a union, but
280      simplicity is more important than memory usage for breakpoints.  */
281 
282   /* Architecture associated with this location's address.  May be
283      different from the breakpoint architecture.  */
284   struct gdbarch *gdbarch;
285 
286   /* The program space associated with this breakpoint location
287      address.  Note that an address space may be represented in more
288      than one program space (e.g. each uClinux program will be given
289      its own program space, but there will only be one address space
290      for all of them), but we must not insert more than one location
291      at the same address in the same address space.  */
292   struct program_space *pspace;
293 
294   /* Note that zero is a perfectly valid code address on some platforms
295      (for example, the mn10200 (OBSOLETE) and mn10300 simulators).  NULL
296      is not a special value for this field.  Valid for all types except
297      bp_loc_other.  */
298   CORE_ADDR address;
299 
300   /* For hardware watchpoints, the size of data ad ADDRESS being watches.  */
301   int length;
302 
303   /* Type of hardware watchpoint. */
304   enum target_hw_bp_type watchpoint_type;
305 
306   /* For any breakpoint type with an address, this is the section
307      associated with the address.  Used primarily for overlay debugging.  */
308   struct obj_section *section;
309 
310   /* Address at which breakpoint was requested, either by the user or
311      by GDB for internal breakpoints.  This will usually be the same
312      as ``address'' (above) except for cases in which
313      ADJUST_BREAKPOINT_ADDRESS has computed a different address at
314      which to place the breakpoint in order to comply with a
315      processor's architectual constraints.  */
316   CORE_ADDR requested_address;
317 
318   char *function_name;
319 
320   /* Details of the placed breakpoint, when inserted.  */
321   struct bp_target_info target_info;
322 
323   /* Similarly, for the breakpoint at an overlay's LMA, if necessary.  */
324   struct bp_target_info overlay_target_info;
325 
326   /* In a non-stop mode, it's possible that we delete a breakpoint,
327      but as we do that, some still running thread hits that breakpoint.
328      For that reason, we need to keep locations belonging to deleted
329      breakpoints for a bit, so that don't report unexpected SIGTRAP.
330      We can't keep such locations forever, so we use a heuristic --
331      after we process certain number of inferior events since
332      breakpoint was deleted, we retire all locations of that breakpoint.
333      This variable keeps a number of events still to go, when
334      it becomes 0 this location is retired.  */
335   int events_till_retirement;
336 };
337 
338 /* This structure is a collection of function pointers that, if available,
339    will be called instead of the performing the default action for this
340    bptype.  */
341 
342 struct breakpoint_ops
343 {
344   /* Insert the breakpoint or activate the catchpoint.  Should raise
345      an exception if the operation failed.  */
346   void (*insert) (struct breakpoint *);
347 
348   /* Remove the breakpoint/catchpoint that was previously inserted
349      with the "insert" method above.  Return non-zero if the operation
350      succeeded.  */
351   int (*remove) (struct breakpoint *);
352 
353   /* Return non-zero if the debugger should tell the user that this
354      breakpoint was hit.  */
355   int (*breakpoint_hit) (struct breakpoint *);
356 
357   /* The normal print routine for this breakpoint, called when we
358      hit it.  */
359   enum print_stop_action (*print_it) (struct breakpoint *);
360 
361   /* Display information about this breakpoint, for "info breakpoints".  */
362   void (*print_one) (struct breakpoint *, struct bp_location **);
363 
364   /* Display information about this breakpoint after setting it (roughly
365      speaking; this is called from "mention").  */
366   void (*print_mention) (struct breakpoint *);
367 
368   /* Print to FP the CLI command that recreates this breakpoint.  */
369   void (*print_recreate) (struct breakpoint *, struct ui_file *fp);
370 };
371 
372 enum watchpoint_triggered
373 {
374   /* This watchpoint definitely did not trigger.  */
375   watch_triggered_no = 0,
376 
377   /* Some hardware watchpoint triggered, and it might have been this
378      one, but we do not know which it was.  */
379   watch_triggered_unknown,
380 
381   /* This hardware watchpoint definitely did trigger.  */
382   watch_triggered_yes
383 };
384 
385 /* This is used to declare the VEC syscalls_to_be_caught.  */
386 DEF_VEC_I(int);
387 
388 typedef struct bp_location *bp_location_p;
389 DEF_VEC_P(bp_location_p);
390 
391 /* A reference-counted struct command_line.  This lets multiple
392    breakpoints share a single command list.  This is an implementation
393    detail to the breakpoints module.  */
394 struct counted_command_line;
395 
396 /* Note that the ->silent field is not currently used by any commands
397    (though the code is in there if it was to be, and set_raw_breakpoint
398    does set it to 0).  I implemented it because I thought it would be
399    useful for a hack I had to put in; I'm going to leave it in because
400    I can see how there might be times when it would indeed be useful */
401 
402 /* This is for a breakpoint or a watchpoint.  */
403 
404 struct breakpoint
405   {
406     struct breakpoint *next;
407     /* Type of breakpoint. */
408     enum bptype type;
409     /* Zero means disabled; remember the info but don't break here.  */
410     enum enable_state enable_state;
411     /* What to do with this breakpoint after we hit it. */
412     enum bpdisp disposition;
413     /* Number assigned to distinguish breakpoints.  */
414     int number;
415 
416     /* Location(s) associated with this high-level breakpoint.  */
417     struct bp_location *loc;
418 
419     /* Line number of this address.  */
420 
421     int line_number;
422 
423     /* Source file name of this address.  */
424 
425     char *source_file;
426 
427     /* Non-zero means a silent breakpoint (don't print frame info
428        if we stop here). */
429     unsigned char silent;
430     /* Number of stops at this breakpoint that should
431        be continued automatically before really stopping.  */
432     int ignore_count;
433     /* Chain of command lines to execute when this breakpoint is hit.  */
434     struct counted_command_line *commands;
435     /* Stack depth (address of frame).  If nonzero, break only if fp
436        equals this.  */
437     struct frame_id frame_id;
438 
439     /* The program space used to set the breakpoint.  */
440     struct program_space *pspace;
441 
442     /* String we used to set the breakpoint (malloc'd).  */
443     char *addr_string;
444     /* Architecture we used to set the breakpoint.  */
445     struct gdbarch *gdbarch;
446     /* Language we used to set the breakpoint.  */
447     enum language language;
448     /* Input radix we used to set the breakpoint.  */
449     int input_radix;
450     /* String form of the breakpoint condition (malloc'd), or NULL if there
451        is no condition.  */
452     char *cond_string;
453     /* String form of exp (malloc'd), or NULL if none.  */
454     char *exp_string;
455 
456     /* The expression we are watching, or NULL if not a watchpoint.  */
457     struct expression *exp;
458     /* The largest block within which it is valid, or NULL if it is
459        valid anywhere (e.g. consists just of global symbols).  */
460     struct block *exp_valid_block;
461     /* The conditional expression if any.  NULL if not a watchpoint.  */
462     struct expression *cond_exp;
463     /* The largest block within which it is valid, or NULL if it is
464        valid anywhere (e.g. consists just of global symbols).  */
465     struct block *cond_exp_valid_block;
466     /* Value of the watchpoint the last time we checked it, or NULL
467        when we do not know the value yet or the value was not
468        readable.  VAL is never lazy.  */
469     struct value *val;
470     /* Nonzero if VAL is valid.  If VAL_VALID is set but VAL is NULL,
471        then an error occurred reading the value.  */
472     int val_valid;
473 
474     /* Holds the address of the related watchpoint_scope breakpoint
475        when using watchpoints on local variables (might the concept
476        of a related breakpoint be useful elsewhere, if not just call
477        it the watchpoint_scope breakpoint or something like that. FIXME).  */
478     struct breakpoint *related_breakpoint;
479 
480     /* Holds the frame address which identifies the frame this
481        watchpoint should be evaluated in, or `null' if the watchpoint
482        should be evaluated on the outermost frame.  */
483     struct frame_id watchpoint_frame;
484 
485     /* Holds the thread which identifies the frame this watchpoint
486        should be considered in scope for, or `null_ptid' if the
487        watchpoint should be evaluated in all threads.  */
488     ptid_t watchpoint_thread;
489 
490     /* For hardware watchpoints, the triggered status according to the
491        hardware.  */
492     enum watchpoint_triggered watchpoint_triggered;
493 
494     /* Thread number for thread-specific breakpoint, or -1 if don't care.  */
495     int thread;
496 
497     /* Ada task number for task-specific breakpoint, or 0 if don't care.  */
498     int task;
499 
500     /* Count of the number of times this breakpoint was taken, dumped
501        with the info, but not used for anything else.  Useful for
502        seeing how many times you hit a break prior to the program
503        aborting, so you can back up to just before the abort.  */
504     int hit_count;
505 
506     /* Process id of a child process whose forking triggered this
507        catchpoint.  This field is only valid immediately after this
508        catchpoint has triggered.  */
509     ptid_t forked_inferior_pid;
510 
511     /* Filename of a program whose exec triggered this catchpoint.
512        This field is only valid immediately after this catchpoint has
513        triggered.  */
514     char *exec_pathname;
515 
516     /* Syscall numbers used for the 'catch syscall' feature.
517        If no syscall has been specified for filtering, its value is NULL.
518        Otherwise, it holds a list of all syscalls to be caught.
519        The list elements are allocated with xmalloc.  */
520     VEC(int) *syscalls_to_be_caught;
521 
522     /* Methods associated with this breakpoint.  */
523     struct breakpoint_ops *ops;
524 
525     /* Is breakpoint's condition not yet parsed because we found
526        no location initially so had no context to parse
527        the condition in.  */
528     int condition_not_parsed;
529 
530     /* Number of times this tracepoint should single-step
531        and collect additional data.  */
532     long step_count;
533 
534     /* Number of times this tracepoint should be hit before
535        disabling/ending.  */
536     int pass_count;
537 
538     /* The number of the tracepoint on the target.  */
539     int number_on_target;
540 
541     /* The static tracepoint marker id, if known.  */
542     char *static_trace_marker_id;
543 
544     /* LTTng/UST allow more than one marker with the same ID string,
545        although it unadvised because it confuses tools.  When setting
546        static tracepoints by marker ID, this will record the index in
547        the array of markers we found for the given marker ID for which
548        this static tracepoint corresponds.  When resetting
549        breakpoints, we will use this index to try to find the same
550        marker again.  */
551     int static_trace_marker_id_idx;
552   };
553 
554 typedef struct breakpoint *breakpoint_p;
555 DEF_VEC_P(breakpoint_p);
556 
557 /* The following stuff is an abstract data type "bpstat" ("breakpoint
558    status").  This provides the ability to determine whether we have
559    stopped at a breakpoint, and what we should do about it.  */
560 
561 typedef struct bpstats *bpstat;
562 
563 /* Frees any storage that is part of a bpstat.
564    Does not walk the 'next' chain.  */
565 extern void bpstat_free (bpstat);
566 
567 /* Clears a chain of bpstat, freeing storage
568    of each.  */
569 extern void bpstat_clear (bpstat *);
570 
571 /* Return a copy of a bpstat.  Like "bs1 = bs2" but all storage that
572    is part of the bpstat is copied as well.  */
573 extern bpstat bpstat_copy (bpstat);
574 
575 extern bpstat bpstat_stop_status (struct address_space *aspace,
576 				  CORE_ADDR pc, ptid_t ptid);
577 
578 /* This bpstat_what stuff tells wait_for_inferior what to do with a
579    breakpoint (a challenging task).
580 
581    The enum values order defines priority-like order of the actions.
582    Once you've decided that some action is appropriate, you'll never
583    go back and decide something of a lower priority is better.  Each
584    of these actions is mutually exclusive with the others.  That
585    means, that if you find yourself adding a new action class here and
586    wanting to tell GDB that you have two simultaneous actions to
587    handle, something is wrong, and you probably don't actually need a
588    new action type.
589 
590    Note that a step resume breakpoint overrides another breakpoint of
591    signal handling (see comment in wait_for_inferior at where we set
592    the step_resume breakpoint).  */
593 
594 enum bpstat_what_main_action
595   {
596     /* Perform various other tests; that is, this bpstat does not
597        say to perform any action (e.g. failed watchpoint and nothing
598        else).  */
599     BPSTAT_WHAT_KEEP_CHECKING,
600 
601     /* Remove breakpoints, single step once, then put them back in and
602        go back to what we were doing.  It's possible that this should be
603        removed from the main_action and put into a separate field, to more
604        cleanly handle BPSTAT_WHAT_CLEAR_LONGJMP_RESUME_SINGLE.  */
605     BPSTAT_WHAT_SINGLE,
606 
607     /* Set longjmp_resume breakpoint, remove all other breakpoints,
608        and continue.  The "remove all other breakpoints" part is required
609        if we are also stepping over another breakpoint as well as doing
610        the longjmp handling.  */
611     BPSTAT_WHAT_SET_LONGJMP_RESUME,
612 
613     /* Clear longjmp_resume breakpoint, then handle as
614        BPSTAT_WHAT_KEEP_CHECKING.  */
615     BPSTAT_WHAT_CLEAR_LONGJMP_RESUME,
616 
617     /* Rather than distinguish between noisy and silent stops here, it
618        might be cleaner to have bpstat_print make that decision (also
619        taking into account stop_print_frame and source_only).  But the
620        implications are a bit scary (interaction with auto-displays, etc.),
621        so I won't try it.  */
622 
623     /* Stop silently.  */
624     BPSTAT_WHAT_STOP_SILENT,
625 
626     /* Stop and print.  */
627     BPSTAT_WHAT_STOP_NOISY,
628 
629     /* Clear step resume breakpoint, and keep checking.  */
630     BPSTAT_WHAT_STEP_RESUME,
631   };
632 
633 /* An enum indicating the kind of "stack dummy" stop.  This is a bit
634    of a misnomer because only one kind of truly a stack dummy.  */
635 enum stop_stack_kind
636   {
637     /* We didn't stop at a stack dummy breakpoint.  */
638     STOP_NONE = 0,
639 
640     /* Stopped at a stack dummy.  */
641     STOP_STACK_DUMMY,
642 
643     /* Stopped at std::terminate.  */
644     STOP_STD_TERMINATE
645   };
646 
647 struct bpstat_what
648   {
649     enum bpstat_what_main_action main_action;
650 
651     /* Did we hit a call dummy breakpoint?  This only goes with a main_action
652        of BPSTAT_WHAT_STOP_SILENT or BPSTAT_WHAT_STOP_NOISY (the concept of
653        continuing from a call dummy without popping the frame is not a
654        useful one).  */
655     enum stop_stack_kind call_dummy;
656   };
657 
658 /* The possible return values for print_bpstat, print_it_normal,
659    print_it_done, print_it_noop. */
660 enum print_stop_action
661   {
662     PRINT_UNKNOWN = -1,
663     PRINT_SRC_AND_LOC,
664     PRINT_SRC_ONLY,
665     PRINT_NOTHING
666   };
667 
668 /* Tell what to do about this bpstat.  */
669 struct bpstat_what bpstat_what (bpstat);
670 
671 /* Find the bpstat associated with a breakpoint.  NULL otherwise. */
672 bpstat bpstat_find_breakpoint (bpstat, struct breakpoint *);
673 
674 /* Nonzero if a signal that we got in wait() was due to circumstances
675    explained by the BS.  */
676 /* Currently that is true if we have hit a breakpoint, or if there is
677    a watchpoint enabled.  */
678 #define bpstat_explains_signal(bs) ((bs) != NULL)
679 
680 /* Nonzero is this bpstat causes a stop.  */
681 extern int bpstat_causes_stop (bpstat);
682 
683 /* Nonzero if we should step constantly (e.g. watchpoints on machines
684    without hardware support).  This isn't related to a specific bpstat,
685    just to things like whether watchpoints are set.  */
686 extern int bpstat_should_step (void);
687 
688 /* Print a message indicating what happened.  Returns nonzero to
689    say that only the source line should be printed after this (zero
690    return means print the frame as well as the source line).  */
691 extern enum print_stop_action bpstat_print (bpstat);
692 
693 /* Put in *NUM the breakpoint number of the first breakpoint we are stopped
694    at.  *BSP upon return is a bpstat which points to the remaining
695    breakpoints stopped at (but which is not guaranteed to be good for
696    anything but further calls to bpstat_num).
697    Return 0 if passed a bpstat which does not indicate any breakpoints.
698    Return -1 if stopped at a breakpoint that has been deleted since
699    we set it.
700    Return 1 otherwise.  */
701 extern int bpstat_num (bpstat *, int *);
702 
703 /* Perform actions associated with the stopped inferior.  Actually, we
704    just use this for breakpoint commands.  Perhaps other actions will
705    go here later, but this is executed at a late time (from the
706    command loop).  */
707 extern void bpstat_do_actions (void);
708 
709 /* Modify BS so that the actions will not be performed.  */
710 extern void bpstat_clear_actions (bpstat);
711 
712 /* Implementation:  */
713 
714 /* Values used to tell the printing routine how to behave for this bpstat. */
715 enum bp_print_how
716   {
717     /* This is used when we want to do a normal printing of the reason
718        for stopping. The output will depend on the type of eventpoint
719        we are dealing with. This is the default value, most commonly
720        used. */
721     print_it_normal,
722     /* This is used when nothing should be printed for this bpstat entry.  */
723     print_it_noop,
724     /* This is used when everything which needs to be printed has
725        already been printed.  But we still want to print the frame.  */
726     print_it_done
727   };
728 
729 struct bpstats
730   {
731     /* Linked list because there can be two breakpoints at the same
732        place, and a bpstat reflects the fact that both have been hit.  */
733     bpstat next;
734     /* Breakpoint that we are at.  */
735     const struct bp_location *breakpoint_at;
736     /* The associated command list.  */
737     struct counted_command_line *commands;
738     /* Commands left to be done.  This points somewhere in
739        base_command.  */
740     struct command_line *commands_left;
741     /* Old value associated with a watchpoint.  */
742     struct value *old_val;
743 
744     /* Nonzero if this breakpoint tells us to print the frame.  */
745     char print;
746 
747     /* Nonzero if this breakpoint tells us to stop.  */
748     char stop;
749 
750     /* Tell bpstat_print and print_bp_stop_message how to print stuff
751        associated with this element of the bpstat chain.  */
752     enum bp_print_how print_it;
753   };
754 
755 enum inf_context
756   {
757     inf_starting,
758     inf_running,
759     inf_exited,
760     inf_execd
761   };
762 
763 /* The possible return values for breakpoint_here_p.
764    We guarantee that zero always means "no breakpoint here".  */
765 enum breakpoint_here
766   {
767     no_breakpoint_here = 0,
768     ordinary_breakpoint_here,
769     permanent_breakpoint_here
770   };
771 
772 
773 /* Prototypes for breakpoint-related functions.  */
774 
775 extern enum breakpoint_here breakpoint_here_p (struct address_space *, CORE_ADDR);
776 
777 extern int moribund_breakpoint_here_p (struct address_space *, CORE_ADDR);
778 
779 extern int breakpoint_inserted_here_p (struct address_space *, CORE_ADDR);
780 
781 extern int regular_breakpoint_inserted_here_p (struct address_space *, CORE_ADDR);
782 
783 extern int software_breakpoint_inserted_here_p (struct address_space *, CORE_ADDR);
784 
785 /* Returns true if there's a hardware watchpoint or access watchpoint
786    inserted in the range defined by ADDR and LEN.  */
787 extern int hardware_watchpoint_inserted_in_range (struct address_space *,
788 						  CORE_ADDR addr,
789 						  ULONGEST len);
790 
791 extern int breakpoint_thread_match (struct address_space *, CORE_ADDR, ptid_t);
792 
793 extern void until_break_command (char *, int, int);
794 
795 extern void breakpoint_re_set (void);
796 
797 extern void breakpoint_re_set_thread (struct breakpoint *);
798 
799 extern struct breakpoint *set_momentary_breakpoint
800   (struct gdbarch *, struct symtab_and_line, struct frame_id, enum bptype);
801 
802 extern struct breakpoint *set_momentary_breakpoint_at_pc
803   (struct gdbarch *, CORE_ADDR pc, enum bptype type);
804 
805 extern struct breakpoint *clone_momentary_breakpoint (struct breakpoint *bpkt);
806 
807 extern void set_ignore_count (int, int, int);
808 
809 extern void set_default_breakpoint (int, struct program_space *,
810 				    CORE_ADDR, struct symtab *, int);
811 
812 extern void breakpoint_init_inferior (enum inf_context);
813 
814 extern struct cleanup *make_cleanup_delete_breakpoint (struct breakpoint *);
815 
816 extern void delete_breakpoint (struct breakpoint *);
817 
818 extern void breakpoint_auto_delete (bpstat);
819 
820 /* Return the chain of command lines to execute when this breakpoint
821    is hit.  */
822 extern struct command_line *breakpoint_commands (struct breakpoint *b);
823 
824 extern void break_command (char *, int);
825 
826 extern void hbreak_command_wrapper (char *, int);
827 extern void thbreak_command_wrapper (char *, int);
828 extern void rbreak_command_wrapper (char *, int);
829 extern void watch_command_wrapper (char *, int);
830 extern void awatch_command_wrapper (char *, int);
831 extern void rwatch_command_wrapper (char *, int);
832 extern void tbreak_command (char *, int);
833 
834 extern int create_breakpoint (struct gdbarch *gdbarch, char *arg,
835 			      char *cond_string, int thread,
836 			      int parse_condition_and_thread,
837 			      int tempflag, enum bptype wanted_type,
838 			      int ignore_count,
839 			      enum auto_boolean pending_break_support,
840 			      struct breakpoint_ops *ops,
841 			      int from_tty,
842 			      int enabled);
843 
844 extern void insert_breakpoints (void);
845 
846 extern int remove_breakpoints (void);
847 
848 extern int remove_breakpoints_pid (int pid);
849 
850 /* This function can be used to physically insert eventpoints from the
851    specified traced inferior process, without modifying the breakpoint
852    package's state.  This can be useful for those targets which support
853    following the processes of a fork() or vfork() system call, when both
854    of the resulting two processes are to be followed.  */
855 extern int reattach_breakpoints (int);
856 
857 /* This function can be used to update the breakpoint package's state
858    after an exec() system call has been executed.
859 
860    This function causes the following:
861 
862    - All eventpoints are marked "not inserted".
863    - All eventpoints with a symbolic address are reset such that
864    the symbolic address must be reevaluated before the eventpoints
865    can be reinserted.
866    - The solib breakpoints are explicitly removed from the breakpoint
867    list.
868    - A step-resume breakpoint, if any, is explicitly removed from the
869    breakpoint list.
870    - All eventpoints without a symbolic address are removed from the
871    breakpoint list. */
872 extern void update_breakpoints_after_exec (void);
873 
874 /* This function can be used to physically remove hardware breakpoints
875    and watchpoints from the specified traced inferior process, without
876    modifying the breakpoint package's state.  This can be useful for
877    those targets which support following the processes of a fork() or
878    vfork() system call, when one of the resulting two processes is to
879    be detached and allowed to run free.
880 
881    It is an error to use this function on the process whose id is
882    inferior_ptid.  */
883 extern int detach_breakpoints (int);
884 
885 /* This function is called when program space PSPACE is about to be
886    deleted.  It takes care of updating breakpoints to not reference
887    this PSPACE anymore.  */
888 extern void breakpoint_program_space_exit (struct program_space *pspace);
889 
890 extern void set_longjmp_breakpoint (int thread);
891 extern void delete_longjmp_breakpoint (int thread);
892 
893 extern void enable_overlay_breakpoints (void);
894 extern void disable_overlay_breakpoints (void);
895 
896 extern void set_std_terminate_breakpoint (void);
897 extern void delete_std_terminate_breakpoint (void);
898 
899 /* These functions respectively disable or reenable all currently
900    enabled watchpoints.  When disabled, the watchpoints are marked
901    call_disabled.  When reenabled, they are marked enabled.
902 
903    The intended client of these functions is call_function_by_hand.
904 
905    The inferior must be stopped, and all breakpoints removed, when
906    these functions are used.
907 
908    The need for these functions is that on some targets (e.g., HP-UX),
909    gdb is unable to unwind through the dummy frame that is pushed as
910    part of the implementation of a call command.  Watchpoints can
911    cause the inferior to stop in places where this frame is visible,
912    and that can cause execution control to become very confused.
913 
914    Note that if a user sets breakpoints in an interactively called
915    function, the call_disabled watchpoints will have been reenabled
916    when the first such breakpoint is reached.  However, on targets
917    that are unable to unwind through the call dummy frame, watches
918    of stack-based storage may then be deleted, because gdb will
919    believe that their watched storage is out of scope.  (Sigh.) */
920 extern void disable_watchpoints_before_interactive_call_start (void);
921 
922 extern void enable_watchpoints_after_interactive_call_stop (void);
923 
924 /* These functions disable and re-enable all breakpoints during
925    inferior startup.  They are intended to be called from solib
926    code where necessary.  This is needed on platforms where the
927    main executable is relocated at some point during startup
928    processing, making breakpoint addresses invalid.
929 
930    If additional breakpoints are created after the routine
931    disable_breakpoints_before_startup but before the routine
932    enable_breakpoints_after_startup was called, they will also
933    be marked as disabled.  */
934 extern void disable_breakpoints_before_startup (void);
935 extern void enable_breakpoints_after_startup (void);
936 
937 /* For script interpreters that need to define breakpoint commands
938    after they've already read the commands into a struct command_line.  */
939 extern enum command_control_type commands_from_control_command
940   (char *arg, struct command_line *cmd);
941 
942 extern void clear_breakpoint_hit_counts (void);
943 
944 extern int get_number (char **);
945 
946 extern int get_number_or_range (char **);
947 
948 extern struct breakpoint *get_breakpoint (int num);
949 
950 /* The following are for displays, which aren't really breakpoints, but
951    here is as good a place as any for them.  */
952 
953 extern void disable_current_display (void);
954 
955 extern void do_displays (void);
956 
957 extern void disable_display (int);
958 
959 extern void clear_displays (void);
960 
961 extern void disable_breakpoint (struct breakpoint *);
962 
963 extern void enable_breakpoint (struct breakpoint *);
964 
965 extern void breakpoint_set_commands (struct breakpoint *b,
966 				     struct command_line *commands);
967 
968 /* Clear the "inserted" flag in all breakpoints.  */
969 extern void mark_breakpoints_out (void);
970 
971 extern void make_breakpoint_permanent (struct breakpoint *);
972 
973 extern struct breakpoint *create_jit_event_breakpoint (struct gdbarch *,
974                                                        CORE_ADDR);
975 
976 extern struct breakpoint *create_solib_event_breakpoint (struct gdbarch *,
977 							 CORE_ADDR);
978 
979 extern struct breakpoint *create_thread_event_breakpoint (struct gdbarch *,
980 							  CORE_ADDR);
981 
982 extern void remove_solib_event_breakpoints (void);
983 
984 extern void remove_thread_event_breakpoints (void);
985 
986 extern void disable_breakpoints_in_shlibs (void);
987 
988 /* This function returns TRUE if ep is a catchpoint. */
989 extern int ep_is_catchpoint (struct breakpoint *);
990 
991 /* Enable breakpoints and delete when hit.  Called with ARG == NULL
992    deletes all breakpoints. */
993 extern void delete_command (char *arg, int from_tty);
994 
995 /* Pull all H/W watchpoints from the target. Return non-zero if the
996    remove fails. */
997 extern int remove_hw_watchpoints (void);
998 
999 /* Manage a software single step breakpoint (or two).  Insert may be called
1000    twice before remove is called.  */
1001 extern void insert_single_step_breakpoint (struct gdbarch *,
1002 					   struct address_space *, CORE_ADDR);
1003 extern void remove_single_step_breakpoints (void);
1004 extern void cancel_single_step_breakpoints (void);
1005 
1006 /* Manage manual breakpoints, separate from the normal chain of
1007    breakpoints.  These functions are used in murky target-specific
1008    ways.  Please do not add more uses!  */
1009 extern void *deprecated_insert_raw_breakpoint (struct gdbarch *,
1010 					       struct address_space *, CORE_ADDR);
1011 extern int deprecated_remove_raw_breakpoint (struct gdbarch *, void *);
1012 
1013 /* Check if any hardware watchpoints have triggered, according to the
1014    target.  */
1015 int watchpoints_triggered (struct target_waitstatus *);
1016 
1017 /* Update BUF, which is LEN bytes read from the target address MEMADDR,
1018    by replacing any memory breakpoints with their shadowed contents.  */
1019 void breakpoint_restore_shadows (gdb_byte *buf, ULONGEST memaddr,
1020 				 LONGEST len);
1021 
1022 extern int breakpoints_always_inserted_mode (void);
1023 
1024 /* Called each time new event from target is processed.
1025    Retires previously deleted breakpoint locations that
1026    in our opinion won't ever trigger.  */
1027 extern void breakpoint_retire_moribund (void);
1028 
1029 /* Set break condition of breakpoint B to EXP.  */
1030 extern void set_breakpoint_condition (struct breakpoint *b, char *exp,
1031 				      int from_tty);
1032 
1033 /* Checks if we are catching syscalls or not.
1034    Returns 0 if not, greater than 0 if we are.  */
1035 extern int catch_syscall_enabled (void);
1036 
1037 /* Checks if we are catching syscalls with the specific
1038    syscall_number.  Used for "filtering" the catchpoints.
1039    Returns 0 if not, greater than 0 if we are.  */
1040 extern int catching_syscall_number (int syscall_number);
1041 
1042 /* Tell a breakpoint to be quiet.  */
1043 extern void make_breakpoint_silent (struct breakpoint *);
1044 
1045 /* Return a tracepoint with the given number if found.  */
1046 extern struct breakpoint *get_tracepoint (int num);
1047 
1048 extern struct breakpoint *get_tracepoint_by_number_on_target (int num);
1049 
1050 /* Find a tracepoint by parsing a number in the supplied string.  */
1051 extern struct breakpoint *get_tracepoint_by_number (char **arg, int multi_p,
1052 						    int optional_p);
1053 
1054 /* Return a vector of all tracepoints currently defined.  The vector
1055    is newly allocated; the caller should free when done with it.  */
1056 extern VEC(breakpoint_p) *all_tracepoints (void);
1057 
1058 extern int is_tracepoint (const struct breakpoint *b);
1059 
1060 /* Return a vector of all static tracepoints defined at ADDR.  The
1061    vector is newly allocated; the caller should free when done with
1062    it.  */
1063 extern VEC(breakpoint_p) *static_tracepoints_here (CORE_ADDR addr);
1064 
1065 /* Function that can be passed to read_command_line to validate
1066    that each command is suitable for tracepoint command list.  */
1067 extern void check_tracepoint_command (char *line, void *closure);
1068 
1069 /* Call at the start and end of an "rbreak" command to register
1070    breakpoint numbers for a later "commands" command.  */
1071 extern void start_rbreak_breakpoints (void);
1072 extern void end_rbreak_breakpoints (void);
1073 
1074 #endif /* !defined (BREAKPOINT_H) */
1075