1 /* Data structures associated with breakpoints in GDB.
2 Copyright (C) 1992 Free Software Foundation, Inc.
4 This file is part of GDB.
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 2 of the License, or
9 (at your option) any later version.
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.
16 You should have received a copy of the GNU General Public License
17 along with this program; if not, write to the Free Software
18 Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */
20 #if !defined (BREAKPOINT_H)
21 #define BREAKPOINT_H 1
26 /* This is the maximum number of bytes a breakpoint instruction can take.
27 Feel free to increase it. It's just used in a few places to size
28 arrays that should be independent of the target architecture. */
30 #define BREAKPOINT_MAX 16
32 /* Type of breakpoint. */
33 /* FIXME In the future, we should fold all other breakpoint-like things into
36 * call-dummy (the breakpoint at the end of a subroutine stub that gdb
37 uses to call functions in the target) (definately).
39 * single-step (for machines where we have to simulate single stepping)
40 (probably, though perhaps it is better for it to look as much as
41 possible like a single-step to wait_for_inferior). */
44 bp_breakpoint
, /* Normal breakpoint */
45 bp_until
, /* used by until command */
46 bp_finish
, /* used by finish command */
47 bp_watchpoint
, /* Watchpoint */
48 bp_longjmp
, /* secret breakpoint to find longjmp() */
49 bp_longjmp_resume
, /* secret breakpoint to escape longjmp() */
51 /* Used by wait_for_inferior for stepping over subroutine calls, for
52 stepping over signal handlers, and for skipping prologues. */
55 /* The breakpoint at the end of a call dummy. */
59 /* States of enablement of breakpoint. */
61 enum enable
{ disabled
, enabled
};
63 /* Disposition of breakpoint. Ie: what to do after hitting it. */
66 delete, /* Delete it */
67 disable
, /* Disable it */
68 donttouch
/* Leave it alone */
71 /* Note that the ->silent field is not currently used by any commands
72 (though the code is in there if it was to be, and set_raw_breakpoint
73 does set it to 0). I implemented it because I thought it would be
74 useful for a hack I had to put in; I'm going to leave it in because
75 I can see how there might be times when it would indeed be useful */
77 /* This is for a breakpoint or a watchpoint. */
81 struct breakpoint
*next
;
82 /* Type of breakpoint. */
84 /* Zero means disabled; remember the info but don't break here. */
86 /* What to do with this breakpoint after we hit it. */
87 enum bpdisp disposition
;
88 /* Number assigned to distinguish breakpoints. */
91 /* Address to break at, or NULL if not a breakpoint. */
94 /* Line number of this address. Only matters if address is
99 /* Source file name of this address. Only matters if address is
104 /* Non-zero means a silent breakpoint (don't print frame info
106 unsigned char silent
;
107 /* Number of stops at this breakpoint that should
108 be continued automatically before really stopping. */
110 /* "Real" contents of byte where breakpoint has been inserted.
111 Valid only when breakpoints are in the program. Under the complete
112 control of the target insert_breakpoint and remove_breakpoint routines.
113 No other code should assume anything about the value(s) here. */
114 char shadow_contents
[BREAKPOINT_MAX
];
115 /* Nonzero if this breakpoint is now inserted. Only matters if address
118 /* Nonzero if this is not the first breakpoint in the list
119 for the given address. Only matters if address is non-NULL. */
121 /* Chain of command lines to execute when this breakpoint is hit. */
122 struct command_line
*commands
;
123 /* Stack depth (address of frame). If nonzero, break only if fp
126 /* Conditional. Break only if this expression's value is nonzero. */
127 struct expression
*cond
;
129 /* String we used to set the breakpoint (malloc'd). Only matters if
130 address is non-NULL. */
132 /* String form of the breakpoint condition (malloc'd), or NULL if there
135 /* String form of exp (malloc'd), or NULL if none. */
138 /* The expression we are watching, or NULL if not a watchpoint. */
139 struct expression
*exp
;
140 /* The largest block within which it is valid, or NULL if it is
141 valid anywhere (e.g. consists just of global symbols). */
142 struct block
*exp_valid_block
;
143 /* Value of the watchpoint the last time we checked it. */
147 /* The following stuff is an abstract data type "bpstat" ("breakpoint status").
148 This provides the ability to determine whether we have stopped at a
149 breakpoint, and what we should do about it. */
151 typedef struct bpstat
*bpstat
;
154 /* Clear a bpstat so that it says we are not at any breakpoint.
155 Also free any storage that is part of a bpstat. */
156 extern void bpstat_clear
PARAMS ((bpstat
*));
158 /* Return a copy of a bpstat. Like "bs1 = bs2" but all storage that
159 is part of the bpstat is copied as well. */
160 extern bpstat bpstat_copy
PARAMS ((bpstat
));
162 /* Get a bpstat associated with having just stopped at address *PC
163 and frame address FRAME_ADDRESS. Update *PC to point at the
164 breakpoint (if we hit a breakpoint). */
165 /* FIXME: prototypes uses equivalence between FRAME_ADDR and CORE_ADDR */
166 extern bpstat bpstat_stop_status
PARAMS ((CORE_ADDR
*, CORE_ADDR
));
168 /* This bpstat_what stuff tells wait_for_inferior what to do with a
169 breakpoint (a challenging task). */
171 enum bpstat_what_main_action
{
172 /* Perform various other tests; that is, this bpstat does not
173 say to perform any action (e.g. failed watchpoint and nothing
175 BPSTAT_WHAT_KEEP_CHECKING
,
177 /* Rather than distinguish between noisy and silent stops here, it
178 might be cleaner to have bpstat_print make that decision (also
179 taking into account stop_print_frame and source_only). But the
180 implications are a bit scary (interaction with auto-displays, etc.),
181 so I won't try it. */
184 BPSTAT_WHAT_STOP_SILENT
,
186 /* Stop and print. */
187 BPSTAT_WHAT_STOP_NOISY
,
189 /* Remove breakpoints, single step once, then put them back in and
190 go back to what we were doing. It's possible that this should be
191 removed from the main_action and put into a separate field, to more
192 cleanly handle BPSTAT_WHAT_CLEAR_LONGJMP_RESUME_SINGLE. */
195 /* Set longjmp_resume breakpoint, remove all other breakpoints,
196 and continue. The "remove all other breakpoints" part is required
197 if we are also stepping over another breakpoint as well as doing
198 the longjmp handling. */
199 BPSTAT_WHAT_SET_LONGJMP_RESUME
,
201 /* Clear longjmp_resume breakpoint, then handle as
202 BPSTAT_WHAT_KEEP_CHECKING. */
203 BPSTAT_WHAT_CLEAR_LONGJMP_RESUME
,
205 /* Clear longjmp_resume breakpoint, then handle as BPSTAT_WHAT_SINGLE. */
206 BPSTAT_WHAT_CLEAR_LONGJMP_RESUME_SINGLE
,
208 /* This is just used to keep track of how many enums there are. */
213 enum bpstat_what_main_action main_action
: 4;
215 /* Did we hit the step resume breakpoint? This is separate from the
216 main_action to allow for it to be combined with any of the main
218 unsigned int step_resume
: 1;
220 /* Did we hit a call dummy breakpoint? This only goes with a main_action
221 of BPSTAT_WHAT_STOP_SILENT or BPSTAT_WHAT_STOP_NOISY (the concept of
222 continuing from a call dummy without popping the frame is not a
224 unsigned int call_dummy
: 1;
227 /* Tell what to do about this bpstat. */
228 struct bpstat_what bpstat_what
PARAMS ((bpstat
));
230 /* Find the bpstat associated with a breakpoint. NULL otherwise. */
231 bpstat bpstat_find_breakpoint
PARAMS ((bpstat
, struct breakpoint
*));
233 /* Nonzero if a signal that we got in wait() was due to circumstances
234 explained by the BS. */
235 /* Currently that is true if we have hit a breakpoint, or if there is
236 a watchpoint enabled. */
237 #define bpstat_explains_signal(bs) ((bs) != NULL)
239 /* Nonzero if we should step constantly (e.g. watchpoints on machines
240 without hardware support). This isn't related to a specific bpstat,
241 just to things like whether watchpoints are set. */
242 extern int bpstat_should_step
PARAMS ((void));
244 /* Print a message indicating what happened. Returns nonzero to
245 say that only the source line should be printed after this (zero
246 return means print the frame as well as the source line). */
247 extern int bpstat_print
PARAMS ((bpstat
));
249 /* Return the breakpoint number of the first breakpoint we are stopped
250 at. *BSP upon return is a bpstat which points to the remaining
251 breakpoints stopped at (but which is not guaranteed to be good for
252 anything but further calls to bpstat_num).
253 Return 0 if passed a bpstat which does not indicate any breakpoints. */
254 extern int bpstat_num
PARAMS ((bpstat
*));
256 /* Perform actions associated with having stopped at *BSP. Actually, we just
257 use this for breakpoint commands. Perhaps other actions will go here
258 later, but this is executed at a late time (from the command loop). */
259 extern void bpstat_do_actions
PARAMS ((bpstat
*));
261 /* Modify BS so that the actions will not be performed. */
262 extern void bpstat_clear_actions
PARAMS ((bpstat
));
264 /* Implementation: */
267 /* Linked list because there can be two breakpoints at the
268 same place, and a bpstat reflects the fact that both have been hit. */
270 /* Breakpoint that we are at. */
271 struct breakpoint
*breakpoint_at
;
272 /* Commands left to be done. */
273 struct command_line
*commands
;
274 /* Old value associated with a watchpoint. */
277 /* Nonzero if this breakpoint tells us to print the frame. */
280 /* Nonzero if this breakpoint tells us to stop. */
283 /* Function called by bpstat_print to print stuff associated with
284 this element of the bpstat chain. Returns 0 or 1 just like
285 bpstat_print, or -1 if it can't deal with it. */
286 int (*print_it
) PARAMS((bpstat bs
));
289 /* Prototypes for breakpoint-related functions. */
291 #ifdef __STDC__ /* Forward declarations for prototypes */
296 breakpoint_here_p
PARAMS ((CORE_ADDR
));
299 until_break_command
PARAMS ((char *, int));
302 breakpoint_re_set
PARAMS ((void));
305 clear_momentary_breakpoints
PARAMS ((void));
307 /* FIXME: Prototype uses equivalence of "struct frame_info *" and FRAME */
308 extern struct breakpoint
*
309 set_momentary_breakpoint
PARAMS ((struct symtab_and_line
,
314 set_ignore_count
PARAMS ((int, int, int));
317 set_default_breakpoint
PARAMS ((int, CORE_ADDR
, struct symtab
*, int));
320 mark_breakpoints_out
PARAMS ((void));
323 delete_breakpoint
PARAMS ((struct breakpoint
*));
326 breakpoint_auto_delete
PARAMS ((bpstat
));
329 breakpoint_clear_ignore_counts
PARAMS ((void));
332 break_command
PARAMS ((char *, int));
335 insert_breakpoints
PARAMS ((void));
338 remove_breakpoints
PARAMS ((void));
341 enable_longjmp_breakpoint
PARAMS ((void));
344 disable_longjmp_breakpoint
PARAMS ((void));
347 set_longjmp_resume_breakpoint
PARAMS ((CORE_ADDR
, FRAME
));
349 /* The following are for displays, which aren't really breakpoints, but
350 here is as good a place as any for them. */
353 disable_current_display
PARAMS ((void));
356 do_displays
PARAMS ((void));
359 disable_display
PARAMS ((int));
362 clear_displays
PARAMS ((void));
364 #endif /* !defined (BREAKPOINT_H) */