1 /* Data structures associated with breakpoints in GDB.
2    Copyright (C) 1992-2021 Free Software Foundation, Inc.
3 
4    This file is part of GDB.
5 
6    This program is free software; you can redistribute it and/or modify
7    it under the terms of the GNU General Public License as published by
8    the Free Software Foundation; either version 3 of the License, or
9    (at your option) any later version.
10 
11    This program is distributed in the hope that it will be useful,
12    but WITHOUT ANY WARRANTY; without even the implied warranty of
13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14    GNU General Public License for more details.
15 
16    You should have received a copy of the GNU General Public License
17    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
18 
19 #if !defined (BREAKPOINT_H)
20 #define BREAKPOINT_H 1
21 
22 #include "frame.h"
23 #include "value.h"
24 #include "ax.h"
25 #include "command.h"
26 #include "gdbsupport/break-common.h"
27 #include "probe.h"
28 #include "location.h"
29 #include <vector>
30 #include "gdbsupport/array-view.h"
31 #include "gdbsupport/filtered-iterator.h"
32 #include "gdbsupport/function-view.h"
33 #include "gdbsupport/refcounted-object.h"
34 #include "gdbsupport/safe-iterator.h"
35 #include "cli/cli-script.h"
36 
37 struct block;
38 struct gdbpy_breakpoint_object;
39 struct gdbscm_breakpoint_object;
40 struct number_or_range_parser;
41 struct thread_info;
42 struct bpstats;
43 struct bp_location;
44 struct linespec_result;
45 struct linespec_sals;
46 struct inferior;
47 
48 /* Enum for exception-handling support in 'catch throw', 'catch rethrow',
49    'catch catch' and the MI equivalent.  */
50 
51 enum exception_event_kind
52 {
53   EX_EVENT_THROW,
54   EX_EVENT_RETHROW,
55   EX_EVENT_CATCH
56 };
57 
58 /* Why are we removing the breakpoint from the target?  */
59 
60 enum remove_bp_reason
61 {
62   /* A regular remove.  Remove the breakpoint and forget everything
63      about it.  */
64   REMOVE_BREAKPOINT,
65 
66   /* Detach the breakpoints from a fork child.  */
67   DETACH_BREAKPOINT,
68 };
69 
70 /* This is the maximum number of bytes a breakpoint instruction can
71    take.  Feel free to increase it.  It's just used in a few places to
72    size arrays that should be independent of the target
73    architecture.  */
74 
75 #define	BREAKPOINT_MAX	16
76 
77 
78 /* Type of breakpoint.  */
79 
80 enum bptype
81   {
82     bp_none = 0,		/* Eventpoint has been deleted */
83     bp_breakpoint,		/* Normal breakpoint */
84     bp_hardware_breakpoint,	/* Hardware assisted breakpoint */
85     bp_single_step,		/* Software single-step */
86     bp_until,			/* used by until command */
87     bp_finish,			/* used by finish command */
88     bp_watchpoint,		/* Watchpoint */
89     bp_hardware_watchpoint,	/* Hardware assisted watchpoint */
90     bp_read_watchpoint,		/* read watchpoint, (hardware assisted) */
91     bp_access_watchpoint,	/* access watchpoint, (hardware assisted) */
92     bp_longjmp,			/* secret breakpoint to find longjmp() */
93     bp_longjmp_resume,		/* secret breakpoint to escape longjmp() */
94 
95     /* Breakpoint placed to the same location(s) like bp_longjmp but used to
96        protect against stale DUMMY_FRAME.  Multiple bp_longjmp_call_dummy and
97        one bp_call_dummy are chained together by related_breakpoint for each
98        DUMMY_FRAME.  */
99     bp_longjmp_call_dummy,
100 
101     /* An internal breakpoint that is installed on the unwinder's
102        debug hook.  */
103     bp_exception,
104     /* An internal breakpoint that is set at the point where an
105        exception will land.  */
106     bp_exception_resume,
107 
108     /* Used by wait_for_inferior for stepping over subroutine calls,
109        and for skipping prologues.  */
110     bp_step_resume,
111 
112     /* Used by wait_for_inferior for stepping over signal
113        handlers.  */
114     bp_hp_step_resume,
115 
116     /* Used to detect when a watchpoint expression has gone out of
117        scope.  These breakpoints are usually not visible to the user.
118 
119        This breakpoint has some interesting properties:
120 
121        1) There's always a 1:1 mapping between watchpoints
122        on local variables and watchpoint_scope breakpoints.
123 
124        2) It automatically deletes itself and the watchpoint it's
125        associated with when hit.
126 
127        3) It can never be disabled.  */
128     bp_watchpoint_scope,
129 
130     /* The breakpoint at the end of a call dummy.  See bp_longjmp_call_dummy it
131        is chained with by related_breakpoint.  */
132     bp_call_dummy,
133 
134     /* A breakpoint set on std::terminate, that is used to catch
135        otherwise uncaught exceptions thrown during an inferior call.  */
136     bp_std_terminate,
137 
138     /* Some dynamic linkers (HP, maybe Solaris) can arrange for special
139        code in the inferior to run when significant events occur in the
140        dynamic linker (for example a library is loaded or unloaded).
141 
142        By placing a breakpoint in this magic code GDB will get control
143        when these significant events occur.  GDB can then re-examine
144        the dynamic linker's data structures to discover any newly loaded
145        dynamic libraries.  */
146     bp_shlib_event,
147 
148     /* Some multi-threaded systems can arrange for a location in the
149        inferior to be executed when certain thread-related events occur
150        (such as thread creation or thread death).
151 
152        By placing a breakpoint at one of these locations, GDB will get
153        control when these events occur.  GDB can then update its thread
154        lists etc.  */
155 
156     bp_thread_event,
157 
158     /* On the same principal, an overlay manager can arrange to call a
159        magic location in the inferior whenever there is an interesting
160        change in overlay status.  GDB can update its overlay tables
161        and fiddle with breakpoints in overlays when this breakpoint
162        is hit.  */
163 
164     bp_overlay_event,
165 
166     /* Master copies of longjmp breakpoints.  These are always installed
167        as soon as an objfile containing longjmp is loaded, but they are
168        always disabled.  While necessary, temporary clones of bp_longjmp
169        type will be created and enabled.  */
170 
171     bp_longjmp_master,
172 
173     /* Master copies of std::terminate breakpoints.  */
174     bp_std_terminate_master,
175 
176     /* Like bp_longjmp_master, but for exceptions.  */
177     bp_exception_master,
178 
179     bp_catchpoint,
180 
181     bp_tracepoint,
182     bp_fast_tracepoint,
183     bp_static_tracepoint,
184 
185     /* A dynamic printf stops at the given location, does a formatted
186        print, then automatically continues.  (Although this is sort of
187        like a macro packaging up standard breakpoint functionality,
188        GDB doesn't have a way to construct types of breakpoint from
189        elements of behavior.)  */
190     bp_dprintf,
191 
192     /* Event for JIT compiled code generation or deletion.  */
193     bp_jit_event,
194 
195     /* Breakpoint is placed at the STT_GNU_IFUNC resolver.  When hit GDB
196        inserts new bp_gnu_ifunc_resolver_return at the caller.
197        bp_gnu_ifunc_resolver is still being kept here as a different thread
198        may still hit it before bp_gnu_ifunc_resolver_return is hit by the
199        original thread.  */
200     bp_gnu_ifunc_resolver,
201 
202     /* On its hit GDB now know the resolved address of the target
203        STT_GNU_IFUNC function.  Associated bp_gnu_ifunc_resolver can be
204        deleted now and the breakpoint moved to the target function entry
205        point.  */
206     bp_gnu_ifunc_resolver_return,
207   };
208 
209 /* States of enablement of breakpoint.  */
210 
211 enum enable_state
212   {
213     bp_disabled,	 /* The eventpoint is inactive, and cannot
214 			    trigger.  */
215     bp_enabled,		 /* The eventpoint is active, and can
216 			    trigger.  */
217     bp_call_disabled,	 /* The eventpoint has been disabled while a
218 			    call into the inferior is "in flight",
219 			    because some eventpoints interfere with
220 			    the implementation of a call on some
221 			    targets.  The eventpoint will be
222 			    automatically enabled and reset when the
223 			    call "lands" (either completes, or stops
224 			    at another eventpoint).  */
225   };
226 
227 
228 /* Disposition of breakpoint.  Ie: what to do after hitting it.  */
229 
230 enum bpdisp
231   {
232     disp_del,			/* Delete it */
233     disp_del_at_next_stop,	/* Delete at next stop,
234 				   whether hit or not */
235     disp_disable,		/* Disable it */
236     disp_donttouch		/* Leave it alone */
237   };
238 
239 /* Status of breakpoint conditions used when synchronizing
240    conditions with the target.  */
241 
242 enum condition_status
243   {
244     condition_unchanged = 0,
245     condition_modified,
246     condition_updated
247   };
248 
249 /* Information used by targets to insert and remove breakpoints.  */
250 
251 struct bp_target_info
252 {
253   /* Address space at which the breakpoint was placed.  */
254   struct address_space *placed_address_space;
255 
256   /* Address at which the breakpoint was placed.  This is normally
257      the same as REQUESTED_ADDRESS, except when adjustment happens in
258      gdbarch_breakpoint_from_pc.  The most common form of adjustment
259      is stripping an alternate ISA marker from the PC which is used
260      to determine the type of breakpoint to insert.  */
261   CORE_ADDR placed_address;
262 
263   /* Address at which the breakpoint was requested.  */
264   CORE_ADDR reqstd_address;
265 
266   /* If this is a ranged breakpoint, then this field contains the
267      length of the range that will be watched for execution.  */
268   int length;
269 
270   /* If the breakpoint lives in memory and reading that memory would
271      give back the breakpoint, instead of the original contents, then
272      the original contents are cached here.  Only SHADOW_LEN bytes of
273      this buffer are valid, and only when the breakpoint is inserted.  */
274   gdb_byte shadow_contents[BREAKPOINT_MAX];
275 
276   /* The length of the data cached in SHADOW_CONTENTS.  */
277   int shadow_len;
278 
279   /* The breakpoint's kind.  It is used in 'kind' parameter in Z
280      packets.  */
281   int kind;
282 
283   /* Conditions the target should evaluate if it supports target-side
284      breakpoint conditions.  These are non-owning pointers.  */
285   std::vector<agent_expr *> conditions;
286 
287   /* Commands the target should evaluate if it supports target-side
288      breakpoint commands.  These are non-owning pointers.  */
289   std::vector<agent_expr *> tcommands;
290 
291   /* Flag that is true if the breakpoint should be left in place even
292      when GDB is not connected.  */
293   int persist;
294 };
295 
296 /* GDB maintains two types of information about each breakpoint (or
297    watchpoint, or other related event).  The first type corresponds
298    to struct breakpoint; this is a relatively high-level structure
299    which contains the source location(s), stopping conditions, user
300    commands to execute when the breakpoint is hit, and so forth.
301 
302    The second type of information corresponds to struct bp_location.
303    Each breakpoint has one or (eventually) more locations associated
304    with it, which represent target-specific and machine-specific
305    mechanisms for stopping the program.  For instance, a watchpoint
306    expression may require multiple hardware watchpoints in order to
307    catch all changes in the value of the expression being watched.  */
308 
309 enum bp_loc_type
310 {
311   bp_loc_software_breakpoint,
312   bp_loc_hardware_breakpoint,
313   bp_loc_hardware_watchpoint,
314   bp_loc_other			/* Miscellaneous...  */
315 };
316 
317 class bp_location : public refcounted_object
318 {
319 public:
320   bp_location () = default;
321 
322   /* Construct a bp_location with the type inferred from OWNER's
323      type.  */
324   explicit bp_location (breakpoint *owner);
325 
326   /* Construct a bp_location with type TYPE.  */
327   bp_location (breakpoint *owner, bp_loc_type type);
328 
329   virtual ~bp_location ();
330 
331   /* Chain pointer to the next breakpoint location for
332      the same parent breakpoint.  */
333   bp_location *next = NULL;
334 
335   /* Type of this breakpoint location.  */
336   bp_loc_type loc_type {};
337 
338   /* Each breakpoint location must belong to exactly one higher-level
339      breakpoint.  This pointer is NULL iff this bp_location is no
340      longer attached to a breakpoint.  For example, when a breakpoint
341      is deleted, its locations may still be found in the
342      moribund_locations list, or if we had stopped for it, in
343      bpstats.  */
344   breakpoint *owner = NULL;
345 
346   /* Conditional.  Break only if this expression's value is nonzero.
347      Unlike string form of condition, which is associated with
348      breakpoint, this is associated with location, since if breakpoint
349      has several locations, the evaluation of expression can be
350      different for different locations.  Only valid for real
351      breakpoints; a watchpoint's conditional expression is stored in
352      the owner breakpoint object.  */
353   expression_up cond;
354 
355   /* Conditional expression in agent expression
356      bytecode form.  This is used for stub-side breakpoint
357      condition evaluation.  */
358   agent_expr_up cond_bytecode;
359 
360   /* Signals that the condition has changed since the last time
361      we updated the global location list.  This means the condition
362      needs to be sent to the target again.  This is used together
363      with target-side breakpoint conditions.
364 
365      condition_unchanged: It means there has been no condition changes.
366 
367      condition_modified: It means this location had its condition modified.
368 
369      condition_updated: It means we already marked all the locations that are
370      duplicates of this location and thus we don't need to call
371      force_breakpoint_reinsertion (...) for this location.  */
372 
373   condition_status condition_changed {};
374 
375   agent_expr_up cmd_bytecode;
376 
377   /* Signals that breakpoint conditions and/or commands need to be
378      re-synced with the target.  This has no use other than
379      target-side breakpoints.  */
380   bool needs_update = false;
381 
382   /* This location's address is in an unloaded solib, and so this
383      location should not be inserted.  It will be automatically
384      enabled when that solib is loaded.  */
385   bool shlib_disabled = false;
386 
387   /* Is this particular location enabled.  */
388   bool enabled = false;
389 
390   /* Is this particular location disabled because the condition
391      expression is invalid at this location.  For a location to be
392      reported as enabled, the ENABLED field above has to be true *and*
393      the DISABLED_BY_COND field has to be false.  */
394   bool disabled_by_cond = false;
395 
396   /* True if this breakpoint is now inserted.  */
397   bool inserted = false;
398 
399   /* True if this is a permanent breakpoint.  There is a breakpoint
400      instruction hard-wired into the target's code.  Don't try to
401      write another breakpoint instruction on top of it, or restore its
402      value.  Step over it using the architecture's
403      gdbarch_skip_permanent_breakpoint method.  */
404   bool permanent = false;
405 
406   /* True if this is not the first breakpoint in the list
407      for the given address.  location of tracepoint can _never_
408      be duplicated with other locations of tracepoints and other
409      kinds of breakpoints, because two locations at the same
410      address may have different actions, so both of these locations
411      should be downloaded and so that `tfind N' always works.  */
412   bool duplicate = false;
413 
414   /* If we someday support real thread-specific breakpoints, then
415      the breakpoint location will need a thread identifier.  */
416 
417   /* Data for specific breakpoint types.  These could be a union, but
418      simplicity is more important than memory usage for breakpoints.  */
419 
420   /* Architecture associated with this location's address.  May be
421      different from the breakpoint architecture.  */
422   struct gdbarch *gdbarch = NULL;
423 
424   /* The program space associated with this breakpoint location
425      address.  Note that an address space may be represented in more
426      than one program space (e.g. each uClinux program will be given
427      its own program space, but there will only be one address space
428      for all of them), but we must not insert more than one location
429      at the same address in the same address space.  */
430   program_space *pspace = NULL;
431 
432   /* Note that zero is a perfectly valid code address on some platforms
433      (for example, the mn10200 (OBSOLETE) and mn10300 simulators).  NULL
434      is not a special value for this field.  Valid for all types except
435      bp_loc_other.  */
436   CORE_ADDR address = 0;
437 
438   /* For hardware watchpoints, the size of the memory region being
439      watched.  For hardware ranged breakpoints, the size of the
440      breakpoint range.  */
441   int length = 0;
442 
443   /* Type of hardware watchpoint.  */
444   target_hw_bp_type watchpoint_type {};
445 
446   /* For any breakpoint type with an address, this is the section
447      associated with the address.  Used primarily for overlay
448      debugging.  */
449   obj_section *section = NULL;
450 
451   /* Address at which breakpoint was requested, either by the user or
452      by GDB for internal breakpoints.  This will usually be the same
453      as ``address'' (above) except for cases in which
454      ADJUST_BREAKPOINT_ADDRESS has computed a different address at
455      which to place the breakpoint in order to comply with a
456      processor's architectual constraints.  */
457   CORE_ADDR requested_address = 0;
458 
459   /* An additional address assigned with this location.  This is currently
460      only used by STT_GNU_IFUNC resolver breakpoints to hold the address
461      of the resolver function.  */
462   CORE_ADDR related_address = 0;
463 
464   /* If the location comes from a probe point, this is the probe associated
465      with it.  */
466   bound_probe probe {};
467 
468   char *function_name = NULL;
469 
470   /* Details of the placed breakpoint, when inserted.  */
471   bp_target_info target_info {};
472 
473   /* Similarly, for the breakpoint at an overlay's LMA, if necessary.  */
474   bp_target_info overlay_target_info {};
475 
476   /* In a non-stop mode, it's possible that we delete a breakpoint,
477      but as we do that, some still running thread hits that breakpoint.
478      For that reason, we need to keep locations belonging to deleted
479      breakpoints for a bit, so that don't report unexpected SIGTRAP.
480      We can't keep such locations forever, so we use a heuristic --
481      after we process certain number of inferior events since
482      breakpoint was deleted, we retire all locations of that breakpoint.
483      This variable keeps a number of events still to go, when
484      it becomes 0 this location is retired.  */
485   int events_till_retirement = 0;
486 
487   /* Line number which was used to place this location.
488 
489      Breakpoint placed into a comment keeps it's user specified line number
490      despite ADDRESS resolves into a different line number.  */
491 
492   int line_number = 0;
493 
494   /* Symtab which was used to place this location.  This is used
495      to find the corresponding source file name.  */
496 
497   struct symtab *symtab = NULL;
498 
499   /* The symbol found by the location parser, if any.  This may be used to
500      ascertain when an event location was set at a different location than
501      the one originally selected by parsing, e.g., inlined symbols.  */
502   const struct symbol *symbol = NULL;
503 
504   /* Similarly, the minimal symbol found by the location parser, if
505      any.  This may be used to ascertain if the location was
506      originally set on a GNU ifunc symbol.  */
507   const minimal_symbol *msymbol = NULL;
508 
509   /* The objfile the symbol or minimal symbol were found in.  */
510   const struct objfile *objfile = NULL;
511 };
512 
513 /* A policy class for bp_location reference counting.  */
514 struct bp_location_ref_policy
515 {
increfbp_location_ref_policy516   static void incref (bp_location *loc)
517   {
518     loc->incref ();
519   }
520 
decrefbp_location_ref_policy521   static void decref (bp_location *loc)
522   {
523     gdb_assert (loc->refcount () > 0);
524     loc->decref ();
525     if (loc->refcount () == 0)
526       delete loc;
527   }
528 };
529 
530 /* A gdb::ref_ptr that has been specialized for bp_location.  */
531 typedef gdb::ref_ptr<bp_location, bp_location_ref_policy>
532      bp_location_ref_ptr;
533 
534 /* The possible return values for print_bpstat, print_it_normal,
535    print_it_done, print_it_noop.  */
536 enum print_stop_action
537 {
538   /* We printed nothing or we need to do some more analysis.  */
539   PRINT_UNKNOWN = -1,
540 
541   /* We printed something, and we *do* desire that something to be
542      followed by a location.  */
543   PRINT_SRC_AND_LOC,
544 
545   /* We printed something, and we do *not* desire that something to be
546      followed by a location.  */
547   PRINT_SRC_ONLY,
548 
549   /* We already printed all we needed to print, don't print anything
550      else.  */
551   PRINT_NOTHING
552 };
553 
554 /* This structure is a collection of function pointers that, if available,
555    will be called instead of the performing the default action for this
556    bptype.  */
557 
558 struct breakpoint_ops
559 {
560   /* Allocate a location for this breakpoint.  */
561   struct bp_location * (*allocate_location) (struct breakpoint *);
562 
563   /* Reevaluate a breakpoint.  This is necessary after symbols change
564      (e.g., an executable or DSO was loaded, or the inferior just
565      started).  */
566   void (*re_set) (struct breakpoint *self);
567 
568   /* Insert the breakpoint or watchpoint or activate the catchpoint.
569      Return 0 for success, 1 if the breakpoint, watchpoint or
570      catchpoint type is not supported, -1 for failure.  */
571   int (*insert_location) (struct bp_location *);
572 
573   /* Remove the breakpoint/catchpoint that was previously inserted
574      with the "insert" method above.  Return 0 for success, 1 if the
575      breakpoint, watchpoint or catchpoint type is not supported,
576      -1 for failure.  */
577   int (*remove_location) (struct bp_location *, enum remove_bp_reason reason);
578 
579   /* Return true if it the target has stopped due to hitting
580      breakpoint location BL.  This function does not check if we
581      should stop, only if BL explains the stop.  ASPACE is the address
582      space in which the event occurred, BP_ADDR is the address at
583      which the inferior stopped, and WS is the target_waitstatus
584      describing the event.  */
585   int (*breakpoint_hit) (const struct bp_location *bl,
586 			 const address_space *aspace,
587 			 CORE_ADDR bp_addr,
588 			 const struct target_waitstatus *ws);
589 
590   /* Check internal conditions of the breakpoint referred to by BS.
591      If we should not stop for this breakpoint, set BS->stop to 0.  */
592   void (*check_status) (struct bpstats *bs);
593 
594   /* Tell how many hardware resources (debug registers) are needed
595      for this breakpoint.  If this function is not provided, then
596      the breakpoint or watchpoint needs one debug register.  */
597   int (*resources_needed) (const struct bp_location *);
598 
599   /* Tell whether we can downgrade from a hardware watchpoint to a software
600      one.  If not, the user will not be able to enable the watchpoint when
601      there are not enough hardware resources available.  */
602   int (*works_in_software_mode) (const struct breakpoint *);
603 
604   /* The normal print routine for this breakpoint, called when we
605      hit it.  */
606   enum print_stop_action (*print_it) (struct bpstats *bs);
607 
608   /* Display information about this breakpoint, for "info
609      breakpoints".  */
610   void (*print_one) (struct breakpoint *, struct bp_location **);
611 
612   /* Display extra information about this breakpoint, below the normal
613      breakpoint description in "info breakpoints".
614 
615      In the example below, the "address range" line was printed
616      by print_one_detail_ranged_breakpoint.
617 
618      (gdb) info breakpoints
619      Num     Type           Disp Enb Address    What
620      2       hw breakpoint  keep y              in main at test-watch.c:70
621 	     address range: [0x10000458, 0x100004c7]
622 
623    */
624   void (*print_one_detail) (const struct breakpoint *, struct ui_out *);
625 
626   /* Display information about this breakpoint after setting it
627      (roughly speaking; this is called from "mention").  */
628   void (*print_mention) (struct breakpoint *);
629 
630   /* Print to FP the CLI command that recreates this breakpoint.  */
631   void (*print_recreate) (struct breakpoint *, struct ui_file *fp);
632 
633   /* Create SALs from location, storing the result in linespec_result.
634 
635      For an explanation about the arguments, see the function
636      `create_sals_from_location_default'.
637 
638      This function is called inside `create_breakpoint'.  */
639   void (*create_sals_from_location) (struct event_location *location,
640 				     struct linespec_result *canonical,
641 				     enum bptype type_wanted);
642 
643   /* This method will be responsible for creating a breakpoint given its SALs.
644      Usually, it just calls `create_breakpoints_sal' (for ordinary
645      breakpoints).  However, there may be some special cases where we might
646      need to do some tweaks, e.g., see
647      `strace_marker_create_breakpoints_sal'.
648 
649      This function is called inside `create_breakpoint'.  */
650   void (*create_breakpoints_sal) (struct gdbarch *,
651 				  struct linespec_result *,
652 				  gdb::unique_xmalloc_ptr<char>,
653 				  gdb::unique_xmalloc_ptr<char>,
654 				  enum bptype, enum bpdisp, int, int,
655 				  int, const struct breakpoint_ops *,
656 				  int, int, int, unsigned);
657 
658   /* Given the location (second parameter), this method decodes it and
659      returns the SAL locations related to it.  For ordinary
660      breakpoints, it calls `decode_line_full'.  If SEARCH_PSPACE is
661      not NULL, symbol search is restricted to just that program space.
662 
663      This function is called inside `location_to_sals'.  */
664   std::vector<symtab_and_line> (*decode_location)
665     (struct breakpoint *b,
666      struct event_location *location,
667      struct program_space *search_pspace);
668 
669   /* Return true if this breakpoint explains a signal.  See
670      bpstat_explains_signal.  */
671   int (*explains_signal) (struct breakpoint *, enum gdb_signal);
672 
673   /* Called after evaluating the breakpoint's condition,
674      and only if it evaluated true.  */
675   void (*after_condition_true) (struct bpstats *bs);
676 };
677 
678 /* Helper for breakpoint_ops->print_recreate implementations.  Prints
679    the "thread" or "task" condition of B, and then a newline.
680 
681    Necessary because most breakpoint implementations accept
682    thread/task conditions at the end of the spec line, like "break foo
683    thread 1", which needs outputting before any breakpoint-type
684    specific extra command necessary for B's recreation.  */
685 extern void print_recreate_thread (struct breakpoint *b, struct ui_file *fp);
686 
687 enum watchpoint_triggered
688 {
689   /* This watchpoint definitely did not trigger.  */
690   watch_triggered_no = 0,
691 
692   /* Some hardware watchpoint triggered, and it might have been this
693      one, but we do not know which it was.  */
694   watch_triggered_unknown,
695 
696   /* This hardware watchpoint definitely did trigger.  */
697   watch_triggered_yes
698 };
699 
700 /* Some targets (e.g., embedded PowerPC) need two debug registers to set
701    a watchpoint over a memory region.  If this flag is true, GDB will use
702    only one register per watchpoint, thus assuming that all accesses that
703    modify a memory location happen at its starting address. */
704 
705 extern bool target_exact_watchpoints;
706 
707 /* bp_location linked list range.  */
708 
709 using bp_locations_range = next_adapter<bp_location>;
710 
711 /* Note that the ->silent field is not currently used by any commands
712    (though the code is in there if it was to be, and set_raw_breakpoint
713    does set it to 0).  I implemented it because I thought it would be
714    useful for a hack I had to put in; I'm going to leave it in because
715    I can see how there might be times when it would indeed be useful */
716 
717 /* This is for all kinds of breakpoints.  */
718 
719 struct breakpoint
720 {
721   virtual ~breakpoint ();
722 
723   /* Return a range of this breakpoint's locations.  */
724   bp_locations_range locations ();
725 
726   /* Methods associated with this breakpoint.  */
727   const breakpoint_ops *ops = NULL;
728 
729   breakpoint *next = NULL;
730   /* Type of breakpoint.  */
731   bptype type = bp_none;
732   /* Zero means disabled; remember the info but don't break here.  */
733   enum enable_state enable_state = bp_enabled;
734   /* What to do with this breakpoint after we hit it.  */
735   bpdisp disposition = disp_del;
736   /* Number assigned to distinguish breakpoints.  */
737   int number = 0;
738 
739   /* Location(s) associated with this high-level breakpoint.  */
740   bp_location *loc = NULL;
741 
742   /* True means a silent breakpoint (don't print frame info if we stop
743      here).  */
744   bool silent = false;
745   /* True means display ADDR_STRING to the user verbatim.  */
746   bool display_canonical = false;
747   /* Number of stops at this breakpoint that should be continued
748      automatically before really stopping.  */
749   int ignore_count = 0;
750 
751   /* Number of stops at this breakpoint before it will be
752      disabled.  */
753   int enable_count = 0;
754 
755   /* Chain of command lines to execute when this breakpoint is
756      hit.  */
757   counted_command_line commands;
758   /* Stack depth (address of frame).  If nonzero, break only if fp
759      equals this.  */
760   struct frame_id frame_id = null_frame_id;
761 
762   /* The program space used to set the breakpoint.  This is only set
763      for breakpoints which are specific to a program space; for
764      non-thread-specific ordinary breakpoints this is NULL.  */
765   program_space *pspace = NULL;
766 
767   /* Location we used to set the breakpoint.  */
768   event_location_up location;
769 
770   /* The filter that should be passed to decode_line_full when
771      re-setting this breakpoint.  This may be NULL.  */
772   gdb::unique_xmalloc_ptr<char> filter;
773 
774   /* For a ranged breakpoint, the location we used to find the end of
775      the range.  */
776   event_location_up location_range_end;
777 
778   /* Architecture we used to set the breakpoint.  */
779   struct gdbarch *gdbarch = NULL;
780   /* Language we used to set the breakpoint.  */
781   enum language language = language_unknown;
782   /* Input radix we used to set the breakpoint.  */
783   int input_radix = 0;
784   /* String form of the breakpoint condition (malloc'd), or NULL if
785      there is no condition.  */
786   char *cond_string = NULL;
787 
788   /* String form of extra parameters, or NULL if there are none.
789      Malloc'd.  */
790   char *extra_string = NULL;
791 
792   /* Holds the address of the related watchpoint_scope breakpoint when
793      using watchpoints on local variables (might the concept of a
794      related breakpoint be useful elsewhere, if not just call it the
795      watchpoint_scope breakpoint or something like that.  FIXME).  */
796   breakpoint *related_breakpoint = NULL;
797 
798   /* Thread number for thread-specific breakpoint, or -1 if don't
799      care.  */
800   int thread = -1;
801 
802   /* Ada task number for task-specific breakpoint, or 0 if don't
803      care.  */
804   int task = 0;
805 
806   /* Count of the number of times this breakpoint was taken, dumped
807      with the info, but not used for anything else.  Useful for seeing
808      how many times you hit a break prior to the program aborting, so
809      you can back up to just before the abort.  */
810   int hit_count = 0;
811 
812   /* Is breakpoint's condition not yet parsed because we found no
813      location initially so had no context to parse the condition
814      in.  */
815   int condition_not_parsed = 0;
816 
817   /* With a Python scripting enabled GDB, store a reference to the
818      Python object that has been associated with this breakpoint.
819      This is always NULL for a GDB that is not script enabled.  It can
820      sometimes be NULL for enabled GDBs as not all breakpoint types
821      are tracked by the scripting language API.  */
822   gdbpy_breakpoint_object *py_bp_object = NULL;
823 
824   /* Same as py_bp_object, but for Scheme.  */
825   gdbscm_breakpoint_object *scm_bp_object = NULL;
826 };
827 
828 /* An instance of this type is used to represent a watchpoint.  */
829 
830 struct watchpoint : public breakpoint
831 {
832   ~watchpoint () override;
833 
834   /* String form of exp to use for displaying to the user (malloc'd),
835      or NULL if none.  */
836   char *exp_string;
837   /* String form to use for reparsing of EXP (malloc'd) or NULL.  */
838   char *exp_string_reparse;
839 
840   /* The expression we are watching, or NULL if not a watchpoint.  */
841   expression_up exp;
842   /* The largest block within which it is valid, or NULL if it is
843      valid anywhere (e.g. consists just of global symbols).  */
844   const struct block *exp_valid_block;
845   /* The conditional expression if any.  */
846   expression_up cond_exp;
847   /* The largest block within which it is valid, or NULL if it is
848      valid anywhere (e.g. consists just of global symbols).  */
849   const struct block *cond_exp_valid_block;
850   /* Value of the watchpoint the last time we checked it, or NULL when
851      we do not know the value yet or the value was not readable.  VAL
852      is never lazy.  */
853   value_ref_ptr val;
854 
855   /* True if VAL is valid.  If VAL_VALID is set but VAL is NULL,
856      then an error occurred reading the value.  */
857   bool val_valid;
858 
859   /* When watching the location of a bitfield, contains the offset and size of
860      the bitfield.  Otherwise contains 0.  */
861   int val_bitpos;
862   int val_bitsize;
863 
864   /* Holds the frame address which identifies the frame this
865      watchpoint should be evaluated in, or `null' if the watchpoint
866      should be evaluated on the outermost frame.  */
867   struct frame_id watchpoint_frame;
868 
869   /* Holds the thread which identifies the frame this watchpoint
870      should be considered in scope for, or `null_ptid' if the
871      watchpoint should be evaluated in all threads.  */
872   ptid_t watchpoint_thread;
873 
874   /* For hardware watchpoints, the triggered status according to the
875      hardware.  */
876   enum watchpoint_triggered watchpoint_triggered;
877 
878   /* Whether this watchpoint is exact (see
879      target_exact_watchpoints).  */
880   int exact;
881 
882   /* The mask address for a masked hardware watchpoint.  */
883   CORE_ADDR hw_wp_mask;
884 };
885 
886 /* Given a function FUNC (struct breakpoint *B, void *DATA) and
887    USER_DATA, call FUNC for every known breakpoint passing USER_DATA
888    as argument.
889 
890    If FUNC returns 1, the loop stops and the current
891    'struct breakpoint' being processed is returned.  If FUNC returns
892    zero, the loop continues.
893 
894    This function returns either a 'struct breakpoint' pointer or NULL.
895    It was based on BFD's bfd_sections_find_if function.  */
896 
897 extern struct breakpoint *breakpoint_find_if
898   (int (*func) (struct breakpoint *b, void *d), void *user_data);
899 
900 /* Return true if BPT is either a software breakpoint or a hardware
901    breakpoint.  */
902 
903 extern bool is_breakpoint (const struct breakpoint *bpt);
904 
905 /* Return true if BPT is of any watchpoint kind, hardware or
906    software.  */
907 
908 extern bool is_watchpoint (const struct breakpoint *bpt);
909 
910 /* Return true if BPT is a C++ exception catchpoint (catch
911    catch/throw/rethrow).  */
912 
913 extern bool is_exception_catchpoint (breakpoint *bp);
914 
915 /* An instance of this type is used to represent all kinds of
916    tracepoints.  */
917 
918 struct tracepoint : public breakpoint
919 {
920   /* Number of times this tracepoint should single-step and collect
921      additional data.  */
922   long step_count;
923 
924   /* Number of times this tracepoint should be hit before
925      disabling/ending.  */
926   int pass_count;
927 
928   /* The number of the tracepoint on the target.  */
929   int number_on_target;
930 
931   /* The total space taken by all the trace frames for this
932      tracepoint.  */
933   ULONGEST traceframe_usage;
934 
935   /* The static tracepoint marker id, if known.  */
936   std::string static_trace_marker_id;
937 
938   /* LTTng/UST allow more than one marker with the same ID string,
939      although it unadvised because it confuses tools.  When setting
940      static tracepoints by marker ID, this will record the index in
941      the array of markers we found for the given marker ID for which
942      this static tracepoint corresponds.  When resetting breakpoints,
943      we will use this index to try to find the same marker again.  */
944   int static_trace_marker_id_idx;
945 };
946 
947 
948 /* The following stuff is an abstract data type "bpstat" ("breakpoint
949    status").  This provides the ability to determine whether we have
950    stopped at a breakpoint, and what we should do about it.  */
951 
952 typedef struct bpstats *bpstat;
953 
954 /* Clears a chain of bpstat, freeing storage
955    of each.  */
956 extern void bpstat_clear (bpstat *);
957 
958 /* Return a copy of a bpstat.  Like "bs1 = bs2" but all storage that
959    is part of the bpstat is copied as well.  */
960 extern bpstat bpstat_copy (bpstat);
961 
962 /* Build the (raw) bpstat chain for the stop information given by ASPACE,
963    BP_ADDR, and WS.  Returns the head of the bpstat chain.  */
964 
965 extern bpstat build_bpstat_chain (const address_space *aspace,
966 				  CORE_ADDR bp_addr,
967 				  const struct target_waitstatus *ws);
968 
969 /* Get a bpstat associated with having just stopped at address
970    BP_ADDR in thread PTID.  STOP_CHAIN may be supplied as a previously
971    computed stop chain or NULL, in which case the stop chain will be
972    computed using build_bpstat_chain.
973 
974    Determine whether we stopped at a breakpoint, etc, or whether we
975    don't understand this stop.  Result is a chain of bpstat's such
976    that:
977 
978    if we don't understand the stop, the result is a null pointer.
979 
980    if we understand why we stopped, the result is not null.
981 
982    Each element of the chain refers to a particular breakpoint or
983    watchpoint at which we have stopped.  (We may have stopped for
984    several reasons concurrently.)
985 
986    Each element of the chain has valid next, breakpoint_at,
987    commands, FIXME??? fields.  */
988 
989 extern bpstat bpstat_stop_status (const address_space *aspace,
990 				  CORE_ADDR pc, thread_info *thread,
991 				  const struct target_waitstatus *ws,
992 				  bpstat stop_chain = NULL);
993 
994 /* This bpstat_what stuff tells wait_for_inferior what to do with a
995    breakpoint (a challenging task).
996 
997    The enum values order defines priority-like order of the actions.
998    Once you've decided that some action is appropriate, you'll never
999    go back and decide something of a lower priority is better.  Each
1000    of these actions is mutually exclusive with the others.  That
1001    means, that if you find yourself adding a new action class here and
1002    wanting to tell GDB that you have two simultaneous actions to
1003    handle, something is wrong, and you probably don't actually need a
1004    new action type.
1005 
1006    Note that a step resume breakpoint overrides another breakpoint of
1007    signal handling (see comment in wait_for_inferior at where we set
1008    the step_resume breakpoint).  */
1009 
1010 enum bpstat_what_main_action
1011   {
1012     /* Perform various other tests; that is, this bpstat does not
1013        say to perform any action (e.g. failed watchpoint and nothing
1014        else).  */
1015     BPSTAT_WHAT_KEEP_CHECKING,
1016 
1017     /* Remove breakpoints, single step once, then put them back in and
1018        go back to what we were doing.  It's possible that this should
1019        be removed from the main_action and put into a separate field,
1020        to more cleanly handle
1021        BPSTAT_WHAT_CLEAR_LONGJMP_RESUME_SINGLE.  */
1022     BPSTAT_WHAT_SINGLE,
1023 
1024     /* Set longjmp_resume breakpoint, remove all other breakpoints,
1025        and continue.  The "remove all other breakpoints" part is
1026        required if we are also stepping over another breakpoint as
1027        well as doing the longjmp handling.  */
1028     BPSTAT_WHAT_SET_LONGJMP_RESUME,
1029 
1030     /* Clear longjmp_resume breakpoint, then handle as
1031        BPSTAT_WHAT_KEEP_CHECKING.  */
1032     BPSTAT_WHAT_CLEAR_LONGJMP_RESUME,
1033 
1034     /* Clear step resume breakpoint, and keep checking.  */
1035     BPSTAT_WHAT_STEP_RESUME,
1036 
1037     /* Rather than distinguish between noisy and silent stops here, it
1038        might be cleaner to have bpstat_print make that decision (also
1039        taking into account stop_print_frame and source_only).  But the
1040        implications are a bit scary (interaction with auto-displays,
1041        etc.), so I won't try it.  */
1042 
1043     /* Stop silently.  */
1044     BPSTAT_WHAT_STOP_SILENT,
1045 
1046     /* Stop and print.  */
1047     BPSTAT_WHAT_STOP_NOISY,
1048 
1049     /* Clear step resume breakpoint, and keep checking.  High-priority
1050        step-resume breakpoints are used when even if there's a user
1051        breakpoint at the current PC when we set the step-resume
1052        breakpoint, we don't want to re-handle any breakpoint other
1053        than the step-resume when it's hit; instead we want to move
1054        past the breakpoint.  This is used in the case of skipping
1055        signal handlers.  */
1056     BPSTAT_WHAT_HP_STEP_RESUME,
1057   };
1058 
1059 /* An enum indicating the kind of "stack dummy" stop.  This is a bit
1060    of a misnomer because only one kind of truly a stack dummy.  */
1061 enum stop_stack_kind
1062   {
1063     /* We didn't stop at a stack dummy breakpoint.  */
1064     STOP_NONE = 0,
1065 
1066     /* Stopped at a stack dummy.  */
1067     STOP_STACK_DUMMY,
1068 
1069     /* Stopped at std::terminate.  */
1070     STOP_STD_TERMINATE
1071   };
1072 
1073 struct bpstat_what
1074   {
1075     enum bpstat_what_main_action main_action;
1076 
1077     /* Did we hit a call dummy breakpoint?  This only goes with a
1078        main_action of BPSTAT_WHAT_STOP_SILENT or
1079        BPSTAT_WHAT_STOP_NOISY (the concept of continuing from a call
1080        dummy without popping the frame is not a useful one).  */
1081     enum stop_stack_kind call_dummy;
1082 
1083     /* Used for BPSTAT_WHAT_SET_LONGJMP_RESUME and
1084        BPSTAT_WHAT_CLEAR_LONGJMP_RESUME.  True if we are handling a
1085        longjmp, false if we are handling an exception.  */
1086     bool is_longjmp;
1087   };
1088 
1089 /* Tell what to do about this bpstat.  */
1090 struct bpstat_what bpstat_what (bpstat);
1091 
1092 /* Run breakpoint event callbacks associated with the breakpoints that
1093    triggered.  */
1094 extern void bpstat_run_callbacks (bpstat bs_head);
1095 
1096 /* Find the bpstat associated with a breakpoint.  NULL otherwise.  */
1097 bpstat bpstat_find_breakpoint (bpstat, struct breakpoint *);
1098 
1099 /* True if a signal that we got in target_wait() was due to
1100    circumstances explained by the bpstat; the signal is therefore not
1101    random.  */
1102 extern bool bpstat_explains_signal (bpstat, enum gdb_signal);
1103 
1104 /* True if this bpstat causes a stop.  */
1105 extern bool bpstat_causes_stop (bpstat);
1106 
1107 /* True if we should step constantly (e.g. watchpoints on machines
1108    without hardware support).  This isn't related to a specific bpstat,
1109    just to things like whether watchpoints are set.  */
1110 extern bool bpstat_should_step ();
1111 
1112 /* Print a message indicating what happened.  Returns nonzero to
1113    say that only the source line should be printed after this (zero
1114    return means print the frame as well as the source line).  */
1115 extern enum print_stop_action bpstat_print (bpstat, int);
1116 
1117 /* Put in *NUM the breakpoint number of the first breakpoint we are
1118    stopped at.  *BSP upon return is a bpstat which points to the
1119    remaining breakpoints stopped at (but which is not guaranteed to be
1120    good for anything but further calls to bpstat_num).
1121 
1122    Return 0 if passed a bpstat which does not indicate any breakpoints.
1123    Return -1 if stopped at a breakpoint that has been deleted since
1124    we set it.
1125    Return 1 otherwise.  */
1126 extern int bpstat_num (bpstat *, int *);
1127 
1128 /* Perform actions associated with the stopped inferior.  Actually, we
1129    just use this for breakpoint commands.  Perhaps other actions will
1130    go here later, but this is executed at a late time (from the
1131    command loop).  */
1132 extern void bpstat_do_actions (void);
1133 
1134 /* Modify all entries of STOP_BPSTAT of INFERIOR_PTID so that the actions will
1135    not be performed.  */
1136 extern void bpstat_clear_actions (void);
1137 
1138 /* Implementation:  */
1139 
1140 /* Values used to tell the printing routine how to behave for this
1141    bpstat.  */
1142 enum bp_print_how
1143   {
1144     /* This is used when we want to do a normal printing of the reason
1145        for stopping.  The output will depend on the type of eventpoint
1146        we are dealing with.  This is the default value, most commonly
1147        used.  */
1148     print_it_normal,
1149     /* This is used when nothing should be printed for this bpstat
1150        entry.  */
1151     print_it_noop,
1152     /* This is used when everything which needs to be printed has
1153        already been printed.  But we still want to print the frame.  */
1154     print_it_done
1155   };
1156 
1157 struct bpstats
1158   {
1159     bpstats ();
1160     bpstats (struct bp_location *bl, bpstat **bs_link_pointer);
1161 
1162     bpstats (const bpstats &);
1163     bpstats &operator= (const bpstats &) = delete;
1164 
1165     /* Linked list because there can be more than one breakpoint at
1166        the same place, and a bpstat reflects the fact that all have
1167        been hit.  */
1168     bpstat next;
1169 
1170     /* Location that caused the stop.  Locations are refcounted, so
1171        this will never be NULL.  Note that this location may end up
1172        detached from a breakpoint, but that does not necessary mean
1173        that the struct breakpoint is gone.  E.g., consider a
1174        watchpoint with a condition that involves an inferior function
1175        call.  Watchpoint locations are recreated often (on resumes,
1176        hence on infcalls too).  Between creating the bpstat and after
1177        evaluating the watchpoint condition, this location may hence
1178        end up detached from its original owner watchpoint, even though
1179        the watchpoint is still listed.  If it's condition evaluates as
1180        true, we still want this location to cause a stop, and we will
1181        still need to know which watchpoint it was originally attached.
1182        What this means is that we should not (in most cases) follow
1183        the `bpstat->bp_location->owner' link, but instead use the
1184        `breakpoint_at' field below.  */
1185     bp_location_ref_ptr bp_location_at;
1186 
1187     /* Breakpoint that caused the stop.  This is nullified if the
1188        breakpoint ends up being deleted.  See comments on
1189        `bp_location_at' above for why do we need this field instead of
1190        following the location's owner.  */
1191     struct breakpoint *breakpoint_at;
1192 
1193     /* The associated command list.  */
1194     counted_command_line commands;
1195 
1196     /* Old value associated with a watchpoint.  */
1197     value_ref_ptr old_val;
1198 
1199     /* Nonzero if this breakpoint tells us to print the frame.  */
1200     char print;
1201 
1202     /* Nonzero if this breakpoint tells us to stop.  */
1203     char stop;
1204 
1205     /* Tell bpstat_print and print_bp_stop_message how to print stuff
1206        associated with this element of the bpstat chain.  */
1207     enum bp_print_how print_it;
1208   };
1209 
1210 enum inf_context
1211   {
1212     inf_starting,
1213     inf_running,
1214     inf_exited,
1215     inf_execd
1216   };
1217 
1218 /* The possible return values for breakpoint_here_p.
1219    We guarantee that zero always means "no breakpoint here".  */
1220 enum breakpoint_here
1221   {
1222     no_breakpoint_here = 0,
1223     ordinary_breakpoint_here,
1224     permanent_breakpoint_here
1225   };
1226 
1227 
1228 /* Prototypes for breakpoint-related functions.  */
1229 
1230 extern enum breakpoint_here breakpoint_here_p (const address_space *,
1231 					       CORE_ADDR);
1232 
1233 /* Return true if an enabled breakpoint exists in the range defined by
1234    ADDR and LEN, in ASPACE.  */
1235 extern int breakpoint_in_range_p (const address_space *aspace,
1236 				  CORE_ADDR addr, ULONGEST len);
1237 
1238 extern int moribund_breakpoint_here_p (const address_space *, CORE_ADDR);
1239 
1240 extern int breakpoint_inserted_here_p (const address_space *,
1241 				       CORE_ADDR);
1242 
1243 extern int software_breakpoint_inserted_here_p (const address_space *,
1244 						CORE_ADDR);
1245 
1246 /* Return non-zero iff there is a hardware breakpoint inserted at
1247    PC.  */
1248 extern int hardware_breakpoint_inserted_here_p (const address_space *,
1249 						CORE_ADDR);
1250 
1251 /* Check whether any location of BP is inserted at PC.  */
1252 
1253 extern int breakpoint_has_location_inserted_here (struct breakpoint *bp,
1254 						  const address_space *aspace,
1255 						  CORE_ADDR pc);
1256 
1257 extern int single_step_breakpoint_inserted_here_p (const address_space *,
1258 						   CORE_ADDR);
1259 
1260 /* Returns true if there's a hardware watchpoint or access watchpoint
1261    inserted in the range defined by ADDR and LEN.  */
1262 extern int hardware_watchpoint_inserted_in_range (const address_space *,
1263 						  CORE_ADDR addr,
1264 						  ULONGEST len);
1265 
1266 /* Returns true if {ASPACE1,ADDR1} and {ASPACE2,ADDR2} represent the
1267    same breakpoint location.  In most targets, this can only be true
1268    if ASPACE1 matches ASPACE2.  On targets that have global
1269    breakpoints, the address space doesn't really matter.  */
1270 
1271 extern int breakpoint_address_match (const address_space *aspace1,
1272 				     CORE_ADDR addr1,
1273 				     const address_space *aspace2,
1274 				     CORE_ADDR addr2);
1275 
1276 extern void until_break_command (const char *, int, int);
1277 
1278 /* Initialize a struct bp_location.  */
1279 
1280 extern void update_breakpoint_locations
1281   (struct breakpoint *b,
1282    struct program_space *filter_pspace,
1283    gdb::array_view<const symtab_and_line> sals,
1284    gdb::array_view<const symtab_and_line> sals_end);
1285 
1286 extern void breakpoint_re_set (void);
1287 
1288 extern void breakpoint_re_set_thread (struct breakpoint *);
1289 
1290 extern void delete_breakpoint (struct breakpoint *);
1291 
1292 struct breakpoint_deleter
1293 {
operatorbreakpoint_deleter1294   void operator() (struct breakpoint *b) const
1295   {
1296     delete_breakpoint (b);
1297   }
1298 };
1299 
1300 typedef std::unique_ptr<struct breakpoint, breakpoint_deleter> breakpoint_up;
1301 
1302 extern breakpoint_up set_momentary_breakpoint
1303   (struct gdbarch *, struct symtab_and_line, struct frame_id, enum bptype);
1304 
1305 extern breakpoint_up set_momentary_breakpoint_at_pc
1306   (struct gdbarch *, CORE_ADDR pc, enum bptype type);
1307 
1308 extern struct breakpoint *clone_momentary_breakpoint (struct breakpoint *bpkt);
1309 
1310 extern void set_ignore_count (int, int, int);
1311 
1312 extern void breakpoint_init_inferior (enum inf_context);
1313 
1314 extern void breakpoint_auto_delete (bpstat);
1315 
1316 /* Return the chain of command lines to execute when this breakpoint
1317    is hit.  */
1318 extern struct command_line *breakpoint_commands (struct breakpoint *b);
1319 
1320 /* Return a string image of DISP.  The string is static, and thus should
1321    NOT be deallocated after use.  */
1322 const char *bpdisp_text (enum bpdisp disp);
1323 
1324 extern void break_command (const char *, int);
1325 
1326 extern void watch_command_wrapper (const char *, int, bool);
1327 extern void awatch_command_wrapper (const char *, int, bool);
1328 extern void rwatch_command_wrapper (const char *, int, bool);
1329 extern void tbreak_command (const char *, int);
1330 
1331 extern struct breakpoint_ops base_breakpoint_ops;
1332 extern struct breakpoint_ops bkpt_breakpoint_ops;
1333 extern struct breakpoint_ops tracepoint_breakpoint_ops;
1334 extern struct breakpoint_ops dprintf_breakpoint_ops;
1335 
1336 extern void initialize_breakpoint_ops (void);
1337 
1338 /* Arguments to pass as context to some catch command handlers.  */
1339 #define CATCH_PERMANENT ((void *) (uintptr_t) 0)
1340 #define CATCH_TEMPORARY ((void *) (uintptr_t) 1)
1341 
1342 /* Like add_cmd, but add the command to both the "catch" and "tcatch"
1343    lists, and pass some additional user data to the command
1344    function.  */
1345 
1346 extern void
1347   add_catch_command (const char *name, const char *docstring,
1348 		     cmd_const_sfunc_ftype *sfunc,
1349 		     completer_ftype *completer,
1350 		     void *user_data_catch,
1351 		     void *user_data_tcatch);
1352 
1353 /* Initialize a breakpoint struct for Ada exception catchpoints.  */
1354 
1355 extern void
1356   init_ada_exception_breakpoint (struct breakpoint *b,
1357 				 struct gdbarch *gdbarch,
1358 				 struct symtab_and_line sal,
1359 				 const char *addr_string,
1360 				 const struct breakpoint_ops *ops,
1361 				 int tempflag,
1362 				 int enabled,
1363 				 int from_tty);
1364 
1365 /* Initialize a new breakpoint of the bp_catchpoint kind.  If TEMP
1366    is true, then make the breakpoint temporary.  If COND_STRING is
1367    not NULL, then store it in the breakpoint.  OPS, if not NULL, is
1368    the breakpoint_ops structure associated to the catchpoint.  */
1369 
1370 extern void init_catchpoint (struct breakpoint *b,
1371 			     struct gdbarch *gdbarch, bool temp,
1372 			     const char *cond_string,
1373 			     const struct breakpoint_ops *ops);
1374 
1375 /* Add breakpoint B on the breakpoint list, and notify the user, the
1376    target and breakpoint_created observers of its existence.  If
1377    INTERNAL is non-zero, the breakpoint number will be allocated from
1378    the internal breakpoint count.  If UPDATE_GLL is non-zero,
1379    update_global_location_list will be called.  */
1380 
1381 extern void install_breakpoint (int internal, std::unique_ptr<breakpoint> &&b,
1382 				int update_gll);
1383 
1384 /* Returns the breakpoint ops appropriate for use with with LOCATION and
1385    according to IS_TRACEPOINT.  Use this to ensure, for example, that you pass
1386    the correct ops to create_breakpoint for probe locations.  If LOCATION is
1387    NULL, returns bkpt_breakpoint_ops (or tracepoint_breakpoint_ops, if
1388    IS_TRACEPOINT is true).  */
1389 
1390 extern const struct breakpoint_ops *breakpoint_ops_for_event_location
1391   (const struct event_location *location, bool is_tracepoint);
1392 
1393 /* Flags that can be passed down to create_breakpoint, etc., to affect
1394    breakpoint creation in several ways.  */
1395 
1396 enum breakpoint_create_flags
1397   {
1398     /* We're adding a breakpoint to our tables that is already
1399        inserted in the target.  */
1400     CREATE_BREAKPOINT_FLAGS_INSERTED = 1 << 0
1401   };
1402 
1403 /* Set a breakpoint.  This function is shared between CLI and MI functions
1404    for setting a breakpoint at LOCATION.
1405 
1406    This function has two major modes of operations, selected by the
1407    PARSE_EXTRA parameter.
1408 
1409    If PARSE_EXTRA is zero, LOCATION is just the breakpoint's location,
1410    with condition, thread, and extra string specified by the COND_STRING,
1411    THREAD, and EXTRA_STRING parameters.
1412 
1413    If PARSE_EXTRA is non-zero, this function will attempt to extract
1414    the condition, thread, and extra string from EXTRA_STRING, ignoring
1415    the similarly named parameters.
1416 
1417    If FORCE_CONDITION is true, the condition is accepted even when it is
1418    invalid at all of the locations.  However, if PARSE_EXTRA is non-zero,
1419    the FORCE_CONDITION parameter is ignored and the corresponding argument
1420    is parsed from EXTRA_STRING.
1421 
1422    If INTERNAL is non-zero, the breakpoint number will be allocated
1423    from the internal breakpoint count.
1424 
1425    Returns true if any breakpoint was created; false otherwise.  */
1426 
1427 extern int create_breakpoint (struct gdbarch *gdbarch,
1428 			      struct event_location *location,
1429 			      const char *cond_string, int thread,
1430 			      const char *extra_string,
1431 			      bool force_condition,
1432 			      int parse_extra,
1433 			      int tempflag, enum bptype wanted_type,
1434 			      int ignore_count,
1435 			      enum auto_boolean pending_break_support,
1436 			      const struct breakpoint_ops *ops,
1437 			      int from_tty,
1438 			      int enabled,
1439 			      int internal, unsigned flags);
1440 
1441 extern void insert_breakpoints (void);
1442 
1443 extern int remove_breakpoints (void);
1444 
1445 /* Remove breakpoints of inferior INF.  */
1446 
1447 extern void remove_breakpoints_inf (inferior *inf);
1448 
1449 /* This function can be used to update the breakpoint package's state
1450    after an exec() system call has been executed.
1451 
1452    This function causes the following:
1453 
1454    - All eventpoints are marked "not inserted".
1455    - All eventpoints with a symbolic address are reset such that
1456    the symbolic address must be reevaluated before the eventpoints
1457    can be reinserted.
1458    - The solib breakpoints are explicitly removed from the breakpoint
1459    list.
1460    - A step-resume breakpoint, if any, is explicitly removed from the
1461    breakpoint list.
1462    - All eventpoints without a symbolic address are removed from the
1463    breakpoint list.  */
1464 extern void update_breakpoints_after_exec (void);
1465 
1466 /* This function can be used to physically remove hardware breakpoints
1467    and watchpoints from the specified traced inferior process, without
1468    modifying the breakpoint package's state.  This can be useful for
1469    those targets which support following the processes of a fork() or
1470    vfork() system call, when one of the resulting two processes is to
1471    be detached and allowed to run free.
1472 
1473    It is an error to use this function on the process whose id is
1474    inferior_ptid.  */
1475 extern int detach_breakpoints (ptid_t ptid);
1476 
1477 /* This function is called when program space PSPACE is about to be
1478    deleted.  It takes care of updating breakpoints to not reference
1479    this PSPACE anymore.  */
1480 extern void breakpoint_program_space_exit (struct program_space *pspace);
1481 
1482 extern void set_longjmp_breakpoint (struct thread_info *tp,
1483 				    struct frame_id frame);
1484 extern void delete_longjmp_breakpoint (int thread);
1485 
1486 /* Mark all longjmp breakpoints from THREAD for later deletion.  */
1487 extern void delete_longjmp_breakpoint_at_next_stop (int thread);
1488 
1489 extern struct breakpoint *set_longjmp_breakpoint_for_call_dummy (void);
1490 extern void check_longjmp_breakpoint_for_call_dummy (struct thread_info *tp);
1491 
1492 extern void enable_overlay_breakpoints (void);
1493 extern void disable_overlay_breakpoints (void);
1494 
1495 extern void set_std_terminate_breakpoint (void);
1496 extern void delete_std_terminate_breakpoint (void);
1497 
1498 /* These functions respectively disable or reenable all currently
1499    enabled watchpoints.  When disabled, the watchpoints are marked
1500    call_disabled.  When re-enabled, they are marked enabled.
1501 
1502    The intended client of these functions is call_function_by_hand.
1503 
1504    The inferior must be stopped, and all breakpoints removed, when
1505    these functions are used.
1506 
1507    The need for these functions is that on some targets (e.g., HP-UX),
1508    gdb is unable to unwind through the dummy frame that is pushed as
1509    part of the implementation of a call command.  Watchpoints can
1510    cause the inferior to stop in places where this frame is visible,
1511    and that can cause execution control to become very confused.
1512 
1513    Note that if a user sets breakpoints in an interactively called
1514    function, the call_disabled watchpoints will have been re-enabled
1515    when the first such breakpoint is reached.  However, on targets
1516    that are unable to unwind through the call dummy frame, watches
1517    of stack-based storage may then be deleted, because gdb will
1518    believe that their watched storage is out of scope.  (Sigh.) */
1519 extern void disable_watchpoints_before_interactive_call_start (void);
1520 
1521 extern void enable_watchpoints_after_interactive_call_stop (void);
1522 
1523 /* These functions disable and re-enable all breakpoints during
1524    inferior startup.  They are intended to be called from solib
1525    code where necessary.  This is needed on platforms where the
1526    main executable is relocated at some point during startup
1527    processing, making breakpoint addresses invalid.
1528 
1529    If additional breakpoints are created after the routine
1530    disable_breakpoints_before_startup but before the routine
1531    enable_breakpoints_after_startup was called, they will also
1532    be marked as disabled.  */
1533 extern void disable_breakpoints_before_startup (void);
1534 extern void enable_breakpoints_after_startup (void);
1535 
1536 /* For script interpreters that need to define breakpoint commands
1537    after they've already read the commands into a struct
1538    command_line.  */
1539 extern enum command_control_type commands_from_control_command
1540   (const char *arg, struct command_line *cmd);
1541 
1542 extern void clear_breakpoint_hit_counts (void);
1543 
1544 extern struct breakpoint *get_breakpoint (int num);
1545 
1546 /* The following are for displays, which aren't really breakpoints,
1547    but here is as good a place as any for them.  */
1548 
1549 extern void disable_current_display (void);
1550 
1551 extern void do_displays (void);
1552 
1553 extern void disable_display (int);
1554 
1555 extern void clear_displays (void);
1556 
1557 extern void disable_breakpoint (struct breakpoint *);
1558 
1559 extern void enable_breakpoint (struct breakpoint *);
1560 
1561 extern void breakpoint_set_commands (struct breakpoint *b,
1562 				     counted_command_line &&commands);
1563 
1564 extern void breakpoint_set_silent (struct breakpoint *b, int silent);
1565 
1566 extern void breakpoint_set_thread (struct breakpoint *b, int thread);
1567 
1568 extern void breakpoint_set_task (struct breakpoint *b, int task);
1569 
1570 /* Clear the "inserted" flag in all breakpoints.  */
1571 extern void mark_breakpoints_out (void);
1572 
1573 extern struct breakpoint *create_jit_event_breakpoint (struct gdbarch *,
1574 						       CORE_ADDR);
1575 
1576 extern struct breakpoint *create_solib_event_breakpoint (struct gdbarch *,
1577 							 CORE_ADDR);
1578 
1579 /* Create an solib event breakpoint at ADDRESS in the current program
1580    space, and immediately try to insert it.  Returns a pointer to the
1581    breakpoint on success.  Deletes the new breakpoint and returns NULL
1582    if inserting the breakpoint fails.  */
1583 extern struct breakpoint *create_and_insert_solib_event_breakpoint
1584   (struct gdbarch *gdbarch, CORE_ADDR address);
1585 
1586 extern struct breakpoint *create_thread_event_breakpoint (struct gdbarch *,
1587 							  CORE_ADDR);
1588 
1589 extern void remove_jit_event_breakpoints (void);
1590 
1591 extern void remove_solib_event_breakpoints (void);
1592 
1593 /* Mark solib event breakpoints of the current program space with
1594    delete at next stop disposition.  */
1595 extern void remove_solib_event_breakpoints_at_next_stop (void);
1596 
1597 extern void disable_breakpoints_in_shlibs (void);
1598 
1599 /* This function returns true if B is a catchpoint.  */
1600 
1601 extern bool is_catchpoint (struct breakpoint *b);
1602 
1603 /* Shared helper function (MI and CLI) for creating and installing
1604    a shared object event catchpoint.  If IS_LOAD is true then
1605    the events to be caught are load events, otherwise they are
1606    unload events.  If IS_TEMP is true the catchpoint is a
1607    temporary one.  If ENABLED is true the catchpoint is
1608    created in an enabled state.  */
1609 
1610 extern void add_solib_catchpoint (const char *arg, bool is_load, bool is_temp,
1611 				  bool enabled);
1612 
1613 /* Create and insert a new software single step breakpoint for the
1614    current thread.  May be called multiple times; each time will add a
1615    new location to the set of potential addresses the next instruction
1616    is at.  */
1617 extern void insert_single_step_breakpoint (struct gdbarch *,
1618 					   const address_space *,
1619 					   CORE_ADDR);
1620 
1621 /* Insert all software single step breakpoints for the current frame.
1622    Return true if any software single step breakpoints are inserted,
1623    otherwise, return false.  */
1624 extern int insert_single_step_breakpoints (struct gdbarch *);
1625 
1626 /* Check if any hardware watchpoints have triggered, according to the
1627    target.  */
1628 int watchpoints_triggered (struct target_waitstatus *);
1629 
1630 /* Helper for transparent breakpoint hiding for memory read and write
1631    routines.
1632 
1633    Update one of READBUF or WRITEBUF with either the shadows
1634    (READBUF), or the breakpoint instructions (WRITEBUF) of inserted
1635    breakpoints at the memory range defined by MEMADDR and extending
1636    for LEN bytes.  If writing, then WRITEBUF is a copy of WRITEBUF_ORG
1637    on entry.*/
1638 extern void breakpoint_xfer_memory (gdb_byte *readbuf, gdb_byte *writebuf,
1639 				    const gdb_byte *writebuf_org,
1640 				    ULONGEST memaddr, LONGEST len);
1641 
1642 /* Return true if breakpoints should be inserted now.  That'll be the
1643    case if either:
1644 
1645     - the target has global breakpoints.
1646 
1647     - "breakpoint always-inserted" is on, and the target has
1648       execution.
1649 
1650     - threads are executing.
1651 */
1652 extern int breakpoints_should_be_inserted_now (void);
1653 
1654 /* Called each time new event from target is processed.
1655    Retires previously deleted breakpoint locations that
1656    in our opinion won't ever trigger.  */
1657 extern void breakpoint_retire_moribund (void);
1658 
1659 /* Set break condition of breakpoint B to EXP.
1660    If FORCE, define the condition even if it is invalid in
1661    all of the breakpoint locations.  */
1662 extern void set_breakpoint_condition (struct breakpoint *b, const char *exp,
1663 				      int from_tty, bool force);
1664 
1665 /* Set break condition for the breakpoint with number BPNUM to EXP.
1666    Raise an error if no breakpoint with the given number is found.
1667    Also raise an error if the breakpoint already has stop conditions.
1668    If FORCE, define the condition even if it is invalid in
1669    all of the breakpoint locations.  */
1670 extern void set_breakpoint_condition (int bpnum, const char *exp,
1671 				      int from_tty, bool force);
1672 
1673 /* Checks if we are catching syscalls or not.
1674    Returns 0 if not, greater than 0 if we are.  */
1675 extern int catch_syscall_enabled (void);
1676 
1677 /* Checks if we are catching syscalls with the specific
1678    syscall_number.  Used for "filtering" the catchpoints.
1679    Returns 0 if not, greater than 0 if we are.  */
1680 extern int catching_syscall_number (int syscall_number);
1681 
1682 /* Return a tracepoint with the given number if found.  */
1683 extern struct tracepoint *get_tracepoint (int num);
1684 
1685 extern struct tracepoint *get_tracepoint_by_number_on_target (int num);
1686 
1687 /* Find a tracepoint by parsing a number in the supplied string.  */
1688 extern struct tracepoint *
1689   get_tracepoint_by_number (const char **arg,
1690 			    number_or_range_parser *parser);
1691 
1692 /* Return true if B is of tracepoint kind.  */
1693 
1694 extern bool is_tracepoint (const struct breakpoint *b);
1695 
1696 /* Return a vector of all static tracepoints defined at ADDR.  */
1697 extern std::vector<breakpoint *> static_tracepoints_here (CORE_ADDR addr);
1698 
1699 /* Create an instance of this to start registering breakpoint numbers
1700    for a later "commands" command.  */
1701 
1702 class scoped_rbreak_breakpoints
1703 {
1704 public:
1705 
1706   scoped_rbreak_breakpoints ();
1707   ~scoped_rbreak_breakpoints ();
1708 
1709   DISABLE_COPY_AND_ASSIGN (scoped_rbreak_breakpoints);
1710 };
1711 
1712 /* Breakpoint linked list iterator.  */
1713 
1714 using breakpoint_iterator = next_iterator<breakpoint>;
1715 
1716 /* Breakpoint linked list range.  */
1717 
1718 using breakpoint_range = next_adapter<breakpoint, breakpoint_iterator>;
1719 
1720 /* Return a range to iterate over all breakpoints.  */
1721 
1722 breakpoint_range all_breakpoints ();
1723 
1724 /* Breakpoint linked list range, safe against deletion of the current
1725    breakpoint while iterating.  */
1726 
1727 using breakpoint_safe_range = basic_safe_range<breakpoint_range>;
1728 
1729 /* Return a range to iterate over all breakpoints.  This range is safe against
1730    deletion of the current breakpoint while iterating.  */
1731 
1732 breakpoint_safe_range all_breakpoints_safe ();
1733 
1734 /* Breakpoint filter to only keep tracepoints.  */
1735 
1736 struct tracepoint_filter
1737 {
operatortracepoint_filter1738   bool operator() (breakpoint *b)
1739   { return is_tracepoint (b); }
1740 };
1741 
1742 /* Breakpoint linked list iterator, filtering to only keep tracepoints.  */
1743 
1744 using tracepoint_iterator
1745   = filtered_iterator<breakpoint_iterator, tracepoint_filter>;
1746 
1747 /* Breakpoint linked list range, filtering to only keep tracepoints.  */
1748 
1749 using tracepoint_range = next_adapter<breakpoint, tracepoint_iterator>;
1750 
1751 /* Return a range to iterate over all tracepoints.  */
1752 
1753 tracepoint_range all_tracepoints ();
1754 
1755 /* Return a range to iterate over all breakpoint locations.  */
1756 
1757 const std::vector<bp_location *> &all_bp_locations ();
1758 
1759 /* Nonzero if the specified PC cannot be a location where functions
1760    have been inlined.  */
1761 
1762 extern int pc_at_non_inline_function (const address_space *aspace,
1763 				      CORE_ADDR pc,
1764 				      const struct target_waitstatus *ws);
1765 
1766 extern int user_breakpoint_p (struct breakpoint *);
1767 
1768 /* Return true if this breakpoint is pending, false if not.  */
1769 extern int pending_breakpoint_p (struct breakpoint *);
1770 
1771 /* Attempt to determine architecture of location identified by SAL.  */
1772 extern struct gdbarch *get_sal_arch (struct symtab_and_line sal);
1773 
1774 extern void breakpoint_free_objfile (struct objfile *objfile);
1775 
1776 extern const char *ep_parse_optional_if_clause (const char **arg);
1777 
1778 /* Print the "Thread ID hit" part of "Thread ID hit Breakpoint N" to
1779    UIOUT iff debugging multiple threads.  */
1780 extern void maybe_print_thread_hit_breakpoint (struct ui_out *uiout);
1781 
1782 /* Print the specified breakpoint.  */
1783 extern void print_breakpoint (breakpoint *bp);
1784 
1785 /* Command element for the 'commands' command.  */
1786 extern cmd_list_element *commands_cmd_element;
1787 
1788 /* Whether to use the fixed output when printing information about a
1789    multi-location breakpoint (see PR 9659).  */
1790 
1791 extern bool fix_multi_location_breakpoint_output_globally;
1792 
1793 /* Deal with "catch catch", "catch throw", and "catch rethrow" commands and
1794    the MI equivalents.  Sets up to catch events of type EX_EVENT.  When
1795    TEMPFLAG is true only the next matching event is caught after which the
1796    catch-point is deleted.  If REGEX is not NULL then only exceptions whose
1797    type name matches REGEX will trigger the event.  */
1798 
1799 extern void catch_exception_event (enum exception_event_kind ex_event,
1800 				   const char *regex, bool tempflag,
1801 				   int from_tty);
1802 
1803 #endif /* !defined (BREAKPOINT_H) */
1804