1 /* Data structures associated with breakpoints in GDB.
2 Copyright 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999, 2000
3 Free Software Foundation, Inc.
5 This file is part of GDB.
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
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.
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 59 Temple Place - Suite 330,
20 Boston, MA 02111-1307, USA. */
22 #if !defined (BREAKPOINT_H)
23 #define BREAKPOINT_H 1
28 #include "gdb-events.h"
33 /* This is the maximum number of bytes a breakpoint instruction can take.
34 Feel free to increase it. It's just used in a few places to size
35 arrays that should be independent of the target architecture. */
37 #define BREAKPOINT_MAX 16
39 /* Type of breakpoint. */
40 /* FIXME In the future, we should fold all other breakpoint-like things into
43 * single-step (for machines where we have to simulate single stepping)
44 (probably, though perhaps it is better for it to look as much as
45 possible like a single-step to wait_for_inferior). */
49 bp_none
= 0, /* Eventpoint has been deleted. */
50 bp_breakpoint
, /* Normal breakpoint */
51 bp_hardware_breakpoint
, /* Hardware assisted breakpoint */
52 bp_until
, /* used by until command */
53 bp_finish
, /* used by finish command */
54 bp_watchpoint
, /* Watchpoint */
55 bp_hardware_watchpoint
, /* Hardware assisted watchpoint */
56 bp_read_watchpoint
, /* read watchpoint, (hardware assisted) */
57 bp_access_watchpoint
, /* access watchpoint, (hardware assisted) */
58 bp_longjmp
, /* secret breakpoint to find longjmp() */
59 bp_longjmp_resume
, /* secret breakpoint to escape longjmp() */
61 /* Used by wait_for_inferior for stepping over subroutine calls, for
62 stepping over signal handlers, and for skipping prologues. */
65 /* Used by wait_for_inferior for stepping over signal handlers. */
68 /* Used to detect when a watchpoint expression has gone out of
69 scope. These breakpoints are usually not visible to the user.
71 This breakpoint has some interesting properties:
73 1) There's always a 1:1 mapping between watchpoints
74 on local variables and watchpoint_scope breakpoints.
76 2) It automatically deletes itself and the watchpoint it's
77 associated with when hit.
79 3) It can never be disabled. */
82 /* The breakpoint at the end of a call dummy. */
83 /* FIXME: What if the function we are calling longjmp()s out of the
84 call, or the user gets out with the "return" command? We currently
85 have no way of cleaning up the breakpoint in these (obscure) situations.
86 (Probably can solve this by noticing longjmp, "return", etc., it's
87 similar to noticing when a watchpoint on a local variable goes out
88 of scope (with hardware support for watchpoints)). */
91 /* Some dynamic linkers (HP, maybe Solaris) can arrange for special
92 code in the inferior to run when significant events occur in the
93 dynamic linker (for example a library is loaded or unloaded).
95 By placing a breakpoint in this magic code GDB will get control
96 when these significant events occur. GDB can then re-examine
97 the dynamic linker's data structures to discover any newly loaded
101 /* Some multi-threaded systems can arrange for a location in the
102 inferior to be executed when certain thread-related events occur
103 (such as thread creation or thread death).
105 By placing a breakpoint at one of these locations, GDB will get
106 control when these events occur. GDB can then update its thread
111 /* On the same principal, an overlay manager can arrange to call a
112 magic location in the inferior whenever there is an interesting
113 change in overlay status. GDB can update its overlay tables
114 and fiddle with breakpoints in overlays when this breakpoint
119 /* These breakpoints are used to implement the "catch load" command
120 on platforms whose dynamic linkers support such functionality. */
123 /* These breakpoints are used to implement the "catch unload" command
124 on platforms whose dynamic linkers support such functionality. */
127 /* These are not really breakpoints, but are catchpoints that
128 implement the "catch fork", "catch vfork" and "catch exec" commands
129 on platforms whose kernel support such functionality. (I.e.,
130 kernels which can raise an event when a fork or exec occurs, as
131 opposed to the debugger setting breakpoints on functions named
132 "fork" or "exec".) */
137 /* These are catchpoints to implement "catch catch" and "catch throw"
138 commands for C++ exception handling. */
145 /* States of enablement of breakpoint. */
149 bp_disabled
, /* The eventpoint is inactive, and cannot trigger. */
150 bp_enabled
, /* The eventpoint is active, and can trigger. */
151 bp_shlib_disabled
, /* The eventpoint's address is in an unloaded solib.
152 The eventpoint will be automatically enabled
153 and reset when that solib is loaded. */
154 bp_call_disabled
, /* The eventpoint has been disabled while a call
155 into the inferior is "in flight", because some
156 eventpoints interfere with the implementation of
157 a call on some targets. The eventpoint will be
158 automatically enabled and reset when the call
159 "lands" (either completes, or stops at another
161 bp_permanent
/* There is a breakpoint instruction hard-wired into
162 the target's code. Don't try to write another
163 breakpoint instruction on top of it, or restore
164 its value. Step over it using the architecture's
169 /* Disposition of breakpoint. Ie: what to do after hitting it. */
173 disp_del
, /* Delete it */
174 disp_del_at_next_stop
, /* Delete at next stop, whether hit or not */
175 disp_disable
, /* Disable it */
176 disp_donttouch
/* Leave it alone */
179 enum target_hw_bp_type
181 hw_write
= 0, /* Common HW watchpoint */
182 hw_read
= 1, /* Read HW watchpoint */
183 hw_access
= 2, /* Access HW watchpoint */
184 hw_execute
= 3 /* Execute HW breakpoint */
187 /* This structure is a collection of function pointers that, if available,
188 will be called instead of the performing the default action for this
191 struct breakpoint_ops
193 /* The normal print routine for this breakpoint, called when we
195 enum print_stop_action (*print_it
) (struct breakpoint
*);
197 /* Display information about this breakpoint, for "info breakpoints". */
198 void (*print_one
) (struct breakpoint
*, CORE_ADDR
*);
200 /* Display information about this breakpoint after setting it (roughly
201 speaking; this is called from "mention"). */
202 void (*print_mention
) (struct breakpoint
*);
205 /* Note that the ->silent field is not currently used by any commands
206 (though the code is in there if it was to be, and set_raw_breakpoint
207 does set it to 0). I implemented it because I thought it would be
208 useful for a hack I had to put in; I'm going to leave it in because
209 I can see how there might be times when it would indeed be useful */
211 /* This is for a breakpoint or a watchpoint. */
215 struct breakpoint
*next
;
216 /* Type of breakpoint. */
218 /* Zero means disabled; remember the info but don't break here. */
219 enum enable_state enable_state
;
220 /* What to do with this breakpoint after we hit it. */
221 enum bpdisp disposition
;
222 /* Number assigned to distinguish breakpoints. */
225 /* Address to break at. Note that zero is a perfectly valid code
226 address on some platforms (for example, the and mn10300
227 simulators). NULL is not a special value for this field. */
230 /* Address at which breakpoint was requested, either by the user or
231 by GDB for internal breakpoints. This will usually be the same
232 as ``address'' (above) except for cases in which
233 ADJUST_BREAKPOINT_ADDRESS has computed a different address at
234 which to place the breakpoint in order to comply with a
235 processor's architectual constraints. */
236 CORE_ADDR requested_address
;
238 /* Line number of this address. */
242 /* Source file name of this address. */
246 /* Non-zero means a silent breakpoint (don't print frame info
248 unsigned char silent
;
249 /* Number of stops at this breakpoint that should
250 be continued automatically before really stopping. */
252 /* "Real" contents of byte where breakpoint has been inserted.
253 Valid only when breakpoints are in the program. Under the complete
254 control of the target insert_breakpoint and remove_breakpoint routines.
255 No other code should assume anything about the value(s) here. */
256 char shadow_contents
[BREAKPOINT_MAX
];
257 /* Nonzero if this breakpoint is now inserted. */
259 /* Nonzero if this is not the first breakpoint in the list
260 for the given address. */
262 /* Chain of command lines to execute when this breakpoint is hit. */
263 struct command_line
*commands
;
264 /* Stack depth (address of frame). If nonzero, break only if fp
266 struct frame_id frame_id
;
267 /* Conditional. Break only if this expression's value is nonzero. */
268 struct expression
*cond
;
270 /* String we used to set the breakpoint (malloc'd). */
272 /* Language we used to set the breakpoint. */
273 enum language language
;
274 /* Input radix we used to set the breakpoint. */
276 /* String form of the breakpoint condition (malloc'd), or NULL if there
279 /* String form of exp (malloc'd), or NULL if none. */
282 /* The expression we are watching, or NULL if not a watchpoint. */
283 struct expression
*exp
;
284 /* The largest block within which it is valid, or NULL if it is
285 valid anywhere (e.g. consists just of global symbols). */
286 struct block
*exp_valid_block
;
287 /* Value of the watchpoint the last time we checked it. */
290 /* Holds the value chain for a hardware watchpoint expression. */
291 struct value
*val_chain
;
293 /* Holds the address of the related watchpoint_scope breakpoint
294 when using watchpoints on local variables (might the concept
295 of a related breakpoint be useful elsewhere, if not just call
296 it the watchpoint_scope breakpoint or something like that. FIXME). */
297 struct breakpoint
*related_breakpoint
;
299 /* Holds the frame address which identifies the frame this
300 watchpoint should be evaluated in, or `null' if the watchpoint
301 should be evaluated on the outermost frame. */
302 struct frame_id watchpoint_frame
;
304 /* Thread number for thread-specific breakpoint, or -1 if don't care */
307 /* Count of the number of times this breakpoint was taken, dumped
308 with the info, but not used for anything else. Useful for
309 seeing how many times you hit a break prior to the program
310 aborting, so you can back up to just before the abort. */
313 /* Filename of a dynamically-linked library (dll), used for
314 bp_catch_load and bp_catch_unload (malloc'd), or NULL if any
315 library is significant. */
318 /* Filename of a dll whose state change (e.g., load or unload)
319 triggered this catchpoint. This field is only valid immediately
320 after this catchpoint has triggered. */
321 char *triggered_dll_pathname
;
323 /* Process id of a child process whose forking triggered this
324 catchpoint. This field is only valid immediately after this
325 catchpoint has triggered. */
326 int forked_inferior_pid
;
328 /* Filename of a program whose exec triggered this catchpoint.
329 This field is only valid immediately after this catchpoint has
335 /* Methods associated with this breakpoint. */
336 struct breakpoint_ops
*ops
;
339 /* The following stuff is an abstract data type "bpstat" ("breakpoint
340 status"). This provides the ability to determine whether we have
341 stopped at a breakpoint, and what we should do about it. */
343 typedef struct bpstats
*bpstat
;
346 /* Clear a bpstat so that it says we are not at any breakpoint.
347 Also free any storage that is part of a bpstat. */
348 extern void bpstat_clear (bpstat
*);
350 /* Return a copy of a bpstat. Like "bs1 = bs2" but all storage that
351 is part of the bpstat is copied as well. */
352 extern bpstat
bpstat_copy (bpstat
);
354 extern bpstat
bpstat_stop_status (CORE_ADDR
*pc
, int not_a_sw_breakpoint
);
356 /* This bpstat_what stuff tells wait_for_inferior what to do with a
357 breakpoint (a challenging task). */
359 enum bpstat_what_main_action
361 /* Perform various other tests; that is, this bpstat does not
362 say to perform any action (e.g. failed watchpoint and nothing
364 BPSTAT_WHAT_KEEP_CHECKING
,
366 /* Rather than distinguish between noisy and silent stops here, it
367 might be cleaner to have bpstat_print make that decision (also
368 taking into account stop_print_frame and source_only). But the
369 implications are a bit scary (interaction with auto-displays, etc.),
370 so I won't try it. */
373 BPSTAT_WHAT_STOP_SILENT
,
375 /* Stop and print. */
376 BPSTAT_WHAT_STOP_NOISY
,
378 /* Remove breakpoints, single step once, then put them back in and
379 go back to what we were doing. It's possible that this should be
380 removed from the main_action and put into a separate field, to more
381 cleanly handle BPSTAT_WHAT_CLEAR_LONGJMP_RESUME_SINGLE. */
384 /* Set longjmp_resume breakpoint, remove all other breakpoints,
385 and continue. The "remove all other breakpoints" part is required
386 if we are also stepping over another breakpoint as well as doing
387 the longjmp handling. */
388 BPSTAT_WHAT_SET_LONGJMP_RESUME
,
390 /* Clear longjmp_resume breakpoint, then handle as
391 BPSTAT_WHAT_KEEP_CHECKING. */
392 BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
,
394 /* Clear longjmp_resume breakpoint, then handle as BPSTAT_WHAT_SINGLE. */
395 BPSTAT_WHAT_CLEAR_LONGJMP_RESUME_SINGLE
,
397 /* Clear step resume breakpoint, and keep checking. */
398 BPSTAT_WHAT_STEP_RESUME
,
400 /* Clear through_sigtramp breakpoint, muck with trap_expected, and keep
402 BPSTAT_WHAT_THROUGH_SIGTRAMP
,
404 /* Check the dynamic linker's data structures for new libraries, then
406 BPSTAT_WHAT_CHECK_SHLIBS
,
408 /* Check the dynamic linker's data structures for new libraries, then
409 resume out of the dynamic linker's callback, stop and print. */
410 BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK
,
412 /* This is just used to keep track of how many enums there are. */
418 enum bpstat_what_main_action main_action
;
420 /* Did we hit a call dummy breakpoint? This only goes with a main_action
421 of BPSTAT_WHAT_STOP_SILENT or BPSTAT_WHAT_STOP_NOISY (the concept of
422 continuing from a call dummy without popping the frame is not a
427 /* The possible return values for print_bpstat, print_it_normal,
428 print_it_done, print_it_noop. */
429 enum print_stop_action
437 /* Tell what to do about this bpstat. */
438 struct bpstat_what
bpstat_what (bpstat
);
440 /* Find the bpstat associated with a breakpoint. NULL otherwise. */
441 bpstat
bpstat_find_breakpoint (bpstat
, struct breakpoint
*);
443 /* Find a step_resume breakpoint associated with this bpstat.
444 (If there are multiple step_resume bp's on the list, this function
445 will arbitrarily pick one.)
447 It is an error to use this function if BPSTAT doesn't contain a
448 step_resume breakpoint.
450 See wait_for_inferior's use of this function.
452 extern struct breakpoint
*bpstat_find_step_resume_breakpoint (bpstat
);
454 /* Nonzero if a signal that we got in wait() was due to circumstances
455 explained by the BS. */
456 /* Currently that is true if we have hit a breakpoint, or if there is
457 a watchpoint enabled. */
458 #define bpstat_explains_signal(bs) ((bs) != NULL)
460 /* Nonzero if we should step constantly (e.g. watchpoints on machines
461 without hardware support). This isn't related to a specific bpstat,
462 just to things like whether watchpoints are set. */
463 extern int bpstat_should_step (void);
465 /* Nonzero if there are enabled hardware watchpoints. */
466 extern int bpstat_have_active_hw_watchpoints (void);
468 /* Print a message indicating what happened. Returns nonzero to
469 say that only the source line should be printed after this (zero
470 return means print the frame as well as the source line). */
471 extern enum print_stop_action
bpstat_print (bpstat
);
473 /* Return the breakpoint number of the first breakpoint we are stopped
474 at. *BSP upon return is a bpstat which points to the remaining
475 breakpoints stopped at (but which is not guaranteed to be good for
476 anything but further calls to bpstat_num).
477 Return 0 if passed a bpstat which does not indicate any breakpoints. */
478 extern int bpstat_num (bpstat
*);
480 /* Perform actions associated with having stopped at *BSP. Actually, we just
481 use this for breakpoint commands. Perhaps other actions will go here
482 later, but this is executed at a late time (from the command loop). */
483 extern void bpstat_do_actions (bpstat
*);
485 /* Modify BS so that the actions will not be performed. */
486 extern void bpstat_clear_actions (bpstat
);
488 /* Given a bpstat that records zero or more triggered eventpoints, this
489 function returns another bpstat which contains only the catchpoints
490 on that first list, if any.
492 extern void bpstat_get_triggered_catchpoints (bpstat
, bpstat
*);
494 /* Implementation: */
496 /* Values used to tell the printing routine how to behave for this bpstat. */
499 /* This is used when we want to do a normal printing of the reason
500 for stopping. The output will depend on the type of eventpoint
501 we are dealing with. This is the default value, most commonly
504 /* This is used when nothing should be printed for this bpstat entry. */
506 /* This is used when everything which needs to be printed has
507 already been printed. But we still want to print the frame. */
513 /* Linked list because there can be two breakpoints at the same
514 place, and a bpstat reflects the fact that both have been hit. */
516 /* Breakpoint that we are at. */
517 struct breakpoint
*breakpoint_at
;
518 /* Commands left to be done. */
519 struct command_line
*commands
;
520 /* Old value associated with a watchpoint. */
521 struct value
*old_val
;
523 /* Nonzero if this breakpoint tells us to print the frame. */
526 /* Nonzero if this breakpoint tells us to stop. */
529 /* Tell bpstat_print and print_bp_stop_message how to print stuff
530 associated with this element of the bpstat chain. */
531 enum bp_print_how print_it
;
541 /* The possible return values for breakpoint_here_p.
542 We guarantee that zero always means "no breakpoint here". */
545 no_breakpoint_here
= 0,
546 ordinary_breakpoint_here
,
547 permanent_breakpoint_here
551 /* Prototypes for breakpoint-related functions. */
553 extern enum breakpoint_here
breakpoint_here_p (CORE_ADDR
);
555 extern int breakpoint_inserted_here_p (CORE_ADDR
);
557 /* FIXME: cagney/2002-11-10: The current [generic] dummy-frame code
558 implements a functional superset of this function. The only reason
559 it hasn't been removed is because some architectures still don't
560 use the new framework. Once they have been fixed, this can go. */
562 extern int deprecated_frame_in_dummy (struct frame_info
*);
564 extern int breakpoint_thread_match (CORE_ADDR
, ptid_t
);
566 extern void until_break_command (char *, int, int);
568 extern void breakpoint_re_set (void);
570 extern void breakpoint_re_set_thread (struct breakpoint
*);
572 extern int ep_is_exception_catchpoint (struct breakpoint
*);
574 extern struct breakpoint
*set_momentary_breakpoint
575 (struct symtab_and_line
, struct frame_id
, enum bptype
);
577 extern void set_ignore_count (int, int, int);
579 extern void set_default_breakpoint (int, CORE_ADDR
, struct symtab
*, int);
581 extern void mark_breakpoints_out (void);
583 extern void breakpoint_init_inferior (enum inf_context
);
585 extern struct cleanup
*make_cleanup_delete_breakpoint (struct breakpoint
*);
587 extern struct cleanup
*make_exec_cleanup_delete_breakpoint (struct breakpoint
*);
589 extern void delete_breakpoint (struct breakpoint
*);
591 extern void breakpoint_auto_delete (bpstat
);
593 extern void breakpoint_clear_ignore_counts (void);
595 extern void break_command (char *, int);
597 extern void hbreak_command_wrapper (char *, int);
598 extern void thbreak_command_wrapper (char *, int);
599 extern void rbreak_command_wrapper (char *, int);
600 extern void watch_command_wrapper (char *, int);
601 extern void awatch_command_wrapper (char *, int);
602 extern void rwatch_command_wrapper (char *, int);
603 extern void tbreak_command (char *, int);
605 extern int insert_breakpoints (void);
607 extern int remove_breakpoints (void);
609 /* This function can be used to physically insert eventpoints from the
610 specified traced inferior process, without modifying the breakpoint
611 package's state. This can be useful for those targets which support
612 following the processes of a fork() or vfork() system call, when both
613 of the resulting two processes are to be followed. */
614 extern int reattach_breakpoints (int);
616 /* This function can be used to update the breakpoint package's state
617 after an exec() system call has been executed.
619 This function causes the following:
621 - All eventpoints are marked "not inserted".
622 - All eventpoints with a symbolic address are reset such that
623 the symbolic address must be reevaluated before the eventpoints
625 - The solib breakpoints are explicitly removed from the breakpoint
627 - A step-resume breakpoint, if any, is explicitly removed from the
629 - All eventpoints without a symbolic address are removed from the
631 extern void update_breakpoints_after_exec (void);
633 /* This function can be used to physically remove hardware breakpoints
634 and watchpoints from the specified traced inferior process, without
635 modifying the breakpoint package's state. This can be useful for
636 those targets which support following the processes of a fork() or
637 vfork() system call, when one of the resulting two processes is to
638 be detached and allowed to run free.
640 It is an error to use this function on the process whose id is
642 extern int detach_breakpoints (int);
644 extern void enable_longjmp_breakpoint (void);
645 extern void disable_longjmp_breakpoint (void);
646 extern void enable_overlay_breakpoints (void);
647 extern void disable_overlay_breakpoints (void);
649 extern void set_longjmp_resume_breakpoint (CORE_ADDR
, struct frame_id
);
650 /* These functions respectively disable or reenable all currently
651 enabled watchpoints. When disabled, the watchpoints are marked
652 call_disabled. When reenabled, they are marked enabled.
654 The intended client of these functions is call_function_by_hand.
656 The inferior must be stopped, and all breakpoints removed, when
657 these functions are used.
659 The need for these functions is that on some targets (e.g., HP-UX),
660 gdb is unable to unwind through the dummy frame that is pushed as
661 part of the implementation of a call command. Watchpoints can
662 cause the inferior to stop in places where this frame is visible,
663 and that can cause execution control to become very confused.
665 Note that if a user sets breakpoints in an interactively called
666 function, the call_disabled watchpoints will have been reenabled
667 when the first such breakpoint is reached. However, on targets
668 that are unable to unwind through the call dummy frame, watches
669 of stack-based storage may then be deleted, because gdb will
670 believe that their watched storage is out of scope. (Sigh.) */
671 extern void disable_watchpoints_before_interactive_call_start (void);
673 extern void enable_watchpoints_after_interactive_call_stop (void);
676 extern void clear_breakpoint_hit_counts (void);
678 extern int get_number (char **);
680 extern int get_number_or_range (char **);
682 /* The following are for displays, which aren't really breakpoints, but
683 here is as good a place as any for them. */
685 extern void disable_current_display (void);
687 extern void do_displays (void);
689 extern void disable_display (int);
691 extern void clear_displays (void);
693 extern void disable_breakpoint (struct breakpoint
*);
695 extern void enable_breakpoint (struct breakpoint
*);
697 extern void make_breakpoint_permanent (struct breakpoint
*);
699 extern struct breakpoint
*create_solib_event_breakpoint (CORE_ADDR
);
701 extern struct breakpoint
*create_thread_event_breakpoint (CORE_ADDR
);
703 extern void remove_solib_event_breakpoints (void);
705 extern void remove_thread_event_breakpoints (void);
707 extern void disable_breakpoints_in_shlibs (int silent
);
709 extern void re_enable_breakpoints_in_shlibs (void);
711 extern void create_solib_load_event_breakpoint (char *, int, char *, char *);
713 extern void create_solib_unload_event_breakpoint (char *, int,
716 extern void create_fork_event_catchpoint (int, char *);
718 extern void create_vfork_event_catchpoint (int, char *);
720 extern void create_exec_event_catchpoint (int, char *);
722 /* This function returns TRUE if ep is a catchpoint. */
723 extern int ep_is_catchpoint (struct breakpoint
*);
725 /* This function returns TRUE if ep is a catchpoint of a
726 shared library (aka dynamically-linked library) event,
727 such as a library load or unload. */
728 extern int ep_is_shlib_catchpoint (struct breakpoint
*);
730 extern struct breakpoint
*set_breakpoint_sal (struct symtab_and_line
);
732 /* Enable breakpoints and delete when hit. Called with ARG == NULL
733 deletes all breakpoints. */
734 extern void delete_command (char *arg
, int from_tty
);
736 /* Pull all H/W watchpoints from the target. Return non-zero if the
738 extern int remove_hw_watchpoints (void);
740 #endif /* !defined (BREAKPOINT_H) */