1 /* Target-struct-independent code to start (run) and stop an inferior
4 Copyright (C) 1986, 1987, 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995,
5 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007
6 Free Software Foundation, Inc.
8 This file is part of GDB.
10 This program is free software; you can redistribute it and/or modify
11 it under the terms of the GNU General Public License as published by
12 the Free Software Foundation; either version 3 of the License, or
13 (at your option) any later version.
15 This program is distributed in the hope that it will be useful,
16 but WITHOUT ANY WARRANTY; without even the implied warranty of
17 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 GNU General Public License for more details.
20 You should have received a copy of the GNU General Public License
21 along with this program. If not, see <http://www.gnu.org/licenses/>. */
24 #include "gdb_string.h"
29 #include "exceptions.h"
30 #include "breakpoint.h"
34 #include "cli/cli-script.h"
36 #include "gdbthread.h"
49 #include "gdb_assert.h"
50 #include "mi/mi-common.h"
52 /* Prototypes for local functions */
54 static void signals_info (char *, int);
56 static void handle_command (char *, int);
58 static void sig_print_info (enum target_signal);
60 static void sig_print_header (void);
62 static void resume_cleanups (void *);
64 static int hook_stop_stub (void *);
66 static int restore_selected_frame (void *);
68 static void build_infrun (void);
70 static int follow_fork (void);
72 static void set_schedlock_func (char *args, int from_tty,
73 struct cmd_list_element *c);
75 struct execution_control_state;
77 static int currently_stepping (struct execution_control_state *ecs);
79 static void xdb_handle_command (char *args, int from_tty);
81 static int prepare_to_proceed (int);
83 void _initialize_infrun (void);
85 int inferior_ignoring_leading_exec_events = 0;
87 /* When set, stop the 'step' command if we enter a function which has
88 no line number information. The normal behavior is that we step
89 over such function. */
90 int step_stop_if_no_debug = 0;
92 show_step_stop_if_no_debug (struct ui_file *file, int from_tty,
93 struct cmd_list_element *c, const char *value)
95 fprintf_filtered (file, _("Mode of the step operation is %s.\n"), value);
98 /* In asynchronous mode, but simulating synchronous execution. */
100 int sync_execution = 0;
102 /* wait_for_inferior and normal_stop use this to notify the user
103 when the inferior stopped in a different thread than it had been
106 static ptid_t previous_inferior_ptid;
108 /* This is true for configurations that may follow through execl() and
109 similar functions. At present this is only true for HP-UX native. */
111 #ifndef MAY_FOLLOW_EXEC
112 #define MAY_FOLLOW_EXEC (0)
115 static int may_follow_exec = MAY_FOLLOW_EXEC;
117 static int debug_infrun = 0;
119 show_debug_infrun (struct ui_file *file, int from_tty,
120 struct cmd_list_element *c, const char *value)
122 fprintf_filtered (file, _("Inferior debugging is %s.\n"), value);
125 /* If the program uses ELF-style shared libraries, then calls to
126 functions in shared libraries go through stubs, which live in a
127 table called the PLT (Procedure Linkage Table). The first time the
128 function is called, the stub sends control to the dynamic linker,
129 which looks up the function's real address, patches the stub so
130 that future calls will go directly to the function, and then passes
131 control to the function.
133 If we are stepping at the source level, we don't want to see any of
134 this --- we just want to skip over the stub and the dynamic linker.
135 The simple approach is to single-step until control leaves the
138 However, on some systems (e.g., Red Hat's 5.2 distribution) the
139 dynamic linker calls functions in the shared C library, so you
140 can't tell from the PC alone whether the dynamic linker is still
141 running. In this case, we use a step-resume breakpoint to get us
142 past the dynamic linker, as if we were using "next" to step over a
145 IN_SOLIB_DYNSYM_RESOLVE_CODE says whether we're in the dynamic
146 linker code or not. Normally, this means we single-step. However,
147 if SKIP_SOLIB_RESOLVER then returns non-zero, then its value is an
148 address where we can place a step-resume breakpoint to get past the
149 linker's symbol resolution function.
151 IN_SOLIB_DYNSYM_RESOLVE_CODE can generally be implemented in a
152 pretty portable way, by comparing the PC against the address ranges
153 of the dynamic linker's sections.
155 SKIP_SOLIB_RESOLVER is generally going to be system-specific, since
156 it depends on internal details of the dynamic linker. It's usually
157 not too hard to figure out where to put a breakpoint, but it
158 certainly isn't portable. SKIP_SOLIB_RESOLVER should do plenty of
159 sanity checking. If it can't figure things out, returning zero and
160 getting the (possibly confusing) stepping behavior is better than
161 signalling an error, which will obscure the change in the
164 /* This function returns TRUE if pc is the address of an instruction
165 that lies within the dynamic linker (such as the event hook, or the
168 This function must be used only when a dynamic linker event has
169 been caught, and the inferior is being stepped out of the hook, or
170 undefined results are guaranteed. */
172 #ifndef SOLIB_IN_DYNAMIC_LINKER
173 #define SOLIB_IN_DYNAMIC_LINKER(pid,pc) 0
177 /* Convert the #defines into values. This is temporary until wfi control
178 flow is completely sorted out. */
180 #ifndef CANNOT_STEP_HW_WATCHPOINTS
181 #define CANNOT_STEP_HW_WATCHPOINTS 0
183 #undef CANNOT_STEP_HW_WATCHPOINTS
184 #define CANNOT_STEP_HW_WATCHPOINTS 1
187 /* Tables of how to react to signals; the user sets them. */
189 static unsigned char *signal_stop;
190 static unsigned char *signal_print;
191 static unsigned char *signal_program;
193 #define SET_SIGS(nsigs,sigs,flags) \
195 int signum = (nsigs); \
196 while (signum-- > 0) \
197 if ((sigs)[signum]) \
198 (flags)[signum] = 1; \
201 #define UNSET_SIGS(nsigs,sigs,flags) \
203 int signum = (nsigs); \
204 while (signum-- > 0) \
205 if ((sigs)[signum]) \
206 (flags)[signum] = 0; \
209 /* Value to pass to target_resume() to cause all threads to resume */
211 #define RESUME_ALL (pid_to_ptid (-1))
213 /* Command list pointer for the "stop" placeholder. */
215 static struct cmd_list_element *stop_command;
217 /* Function inferior was in as of last step command. */
219 static struct symbol *step_start_function;
221 /* Nonzero if we are presently stepping over a breakpoint.
223 If we hit a breakpoint or watchpoint, and then continue,
224 we need to single step the current thread with breakpoints
225 disabled, to avoid hitting the same breakpoint or
226 watchpoint again. And we should step just a single
227 thread and keep other threads stopped, so that
228 other threads don't miss breakpoints while they are removed.
230 So, this variable simultaneously means that we need to single
231 step the current thread, keep other threads stopped, and that
232 breakpoints should be removed while we step.
234 This variable is set either:
235 - in proceed, when we resume inferior on user's explicit request
236 - in keep_going, if handle_inferior_event decides we need to
237 step over breakpoint.
239 The variable is cleared in clear_proceed_status, called every
240 time before we call proceed. The proceed calls wait_for_inferior,
241 which calls handle_inferior_event in a loop, and until
242 wait_for_inferior exits, this variable is changed only by keep_going. */
244 static int stepping_over_breakpoint;
246 /* Nonzero if we want to give control to the user when we're notified
247 of shared library events by the dynamic linker. */
248 static int stop_on_solib_events;
250 show_stop_on_solib_events (struct ui_file *file, int from_tty,
251 struct cmd_list_element *c, const char *value)
253 fprintf_filtered (file, _("Stopping for shared library events is %s.\n"),
257 /* Nonzero means expecting a trace trap
258 and should stop the inferior and return silently when it happens. */
262 /* Nonzero means expecting a trap and caller will handle it themselves.
263 It is used after attach, due to attaching to a process;
264 when running in the shell before the child program has been exec'd;
265 and when running some kinds of remote stuff (FIXME?). */
267 enum stop_kind stop_soon;
269 /* Nonzero if proceed is being used for a "finish" command or a similar
270 situation when stop_registers should be saved. */
272 int proceed_to_finish;
274 /* Save register contents here when about to pop a stack dummy frame,
275 if-and-only-if proceed_to_finish is set.
276 Thus this contains the return value from the called function (assuming
277 values are returned in a register). */
279 struct regcache *stop_registers;
281 /* Nonzero after stop if current stack frame should be printed. */
283 static int stop_print_frame;
285 static struct breakpoint *step_resume_breakpoint = NULL;
287 /* This is a cached copy of the pid/waitstatus of the last event
288 returned by target_wait()/deprecated_target_wait_hook(). This
289 information is returned by get_last_target_status(). */
290 static ptid_t target_last_wait_ptid;
291 static struct target_waitstatus target_last_waitstatus;
293 /* This is used to remember when a fork, vfork or exec event
294 was caught by a catchpoint, and thus the event is to be
295 followed at the next resume of the inferior, and not
299 enum target_waitkind kind;
306 char *execd_pathname;
310 static const char follow_fork_mode_child[] = "child";
311 static const char follow_fork_mode_parent[] = "parent";
313 static const char *follow_fork_mode_kind_names[] = {
314 follow_fork_mode_child,
315 follow_fork_mode_parent,
319 static const char *follow_fork_mode_string = follow_fork_mode_parent;
321 show_follow_fork_mode_string (struct ui_file *file, int from_tty,
322 struct cmd_list_element *c, const char *value)
324 fprintf_filtered (file, _("\
325 Debugger response to a program call of fork or vfork is \"%s\".\n"),
333 int follow_child = (follow_fork_mode_string == follow_fork_mode_child);
335 return target_follow_fork (follow_child);
339 follow_inferior_reset_breakpoints (void)
341 /* Was there a step_resume breakpoint? (There was if the user
342 did a "next" at the fork() call.) If so, explicitly reset its
345 step_resumes are a form of bp that are made to be per-thread.
346 Since we created the step_resume bp when the parent process
347 was being debugged, and now are switching to the child process,
348 from the breakpoint package's viewpoint, that's a switch of
349 "threads". We must update the bp's notion of which thread
350 it is for, or it'll be ignored when it triggers. */
352 if (step_resume_breakpoint)
353 breakpoint_re_set_thread (step_resume_breakpoint);
355 /* Reinsert all breakpoints in the child. The user may have set
356 breakpoints after catching the fork, in which case those
357 were never set in the child, but only in the parent. This makes
358 sure the inserted breakpoints match the breakpoint list. */
360 breakpoint_re_set ();
361 insert_breakpoints ();
364 /* EXECD_PATHNAME is assumed to be non-NULL. */
367 follow_exec (int pid, char *execd_pathname)
370 struct target_ops *tgt;
372 if (!may_follow_exec)
375 /* This is an exec event that we actually wish to pay attention to.
376 Refresh our symbol table to the newly exec'd program, remove any
379 If there are breakpoints, they aren't really inserted now,
380 since the exec() transformed our inferior into a fresh set
383 We want to preserve symbolic breakpoints on the list, since
384 we have hopes that they can be reset after the new a.out's
385 symbol table is read.
387 However, any "raw" breakpoints must be removed from the list
388 (e.g., the solib bp's), since their address is probably invalid
391 And, we DON'T want to call delete_breakpoints() here, since
392 that may write the bp's "shadow contents" (the instruction
393 value that was overwritten witha TRAP instruction). Since
394 we now have a new a.out, those shadow contents aren't valid. */
395 update_breakpoints_after_exec ();
397 /* If there was one, it's gone now. We cannot truly step-to-next
398 statement through an exec(). */
399 step_resume_breakpoint = NULL;
400 step_range_start = 0;
403 /* What is this a.out's name? */
404 printf_unfiltered (_("Executing new program: %s\n"), execd_pathname);
406 /* We've followed the inferior through an exec. Therefore, the
407 inferior has essentially been killed & reborn. */
409 /* First collect the run target in effect. */
410 tgt = find_run_target ();
411 /* If we can't find one, things are in a very strange state... */
413 error (_("Could find run target to save before following exec"));
415 gdb_flush (gdb_stdout);
416 target_mourn_inferior ();
417 inferior_ptid = pid_to_ptid (saved_pid);
418 /* Because mourn_inferior resets inferior_ptid. */
421 /* That a.out is now the one to use. */
422 exec_file_attach (execd_pathname, 0);
424 /* And also is where symbols can be found. */
425 symbol_file_add_main (execd_pathname, 0);
427 /* Reset the shared library package. This ensures that we get
428 a shlib event when the child reaches "_start", at which point
429 the dld will have had a chance to initialize the child. */
430 #if defined(SOLIB_RESTART)
433 #ifdef SOLIB_CREATE_INFERIOR_HOOK
434 SOLIB_CREATE_INFERIOR_HOOK (PIDGET (inferior_ptid));
436 solib_create_inferior_hook ();
439 /* Reinsert all breakpoints. (Those which were symbolic have
440 been reset to the proper address in the new a.out, thanks
441 to symbol_file_command...) */
442 insert_breakpoints ();
444 /* The next resume of this inferior should bring it to the shlib
445 startup breakpoints. (If the user had also set bp's on
446 "main" from the old (parent) process, then they'll auto-
447 matically get reset there in the new process.) */
450 /* Non-zero if we just simulating a single-step. This is needed
451 because we cannot remove the breakpoints in the inferior process
452 until after the `wait' in `wait_for_inferior'. */
453 static int singlestep_breakpoints_inserted_p = 0;
455 /* The thread we inserted single-step breakpoints for. */
456 static ptid_t singlestep_ptid;
458 /* PC when we started this single-step. */
459 static CORE_ADDR singlestep_pc;
461 /* If another thread hit the singlestep breakpoint, we save the original
462 thread here so that we can resume single-stepping it later. */
463 static ptid_t saved_singlestep_ptid;
464 static int stepping_past_singlestep_breakpoint;
466 /* If not equal to null_ptid, this means that after stepping over breakpoint
467 is finished, we need to switch to deferred_step_ptid, and step it.
469 The use case is when one thread has hit a breakpoint, and then the user
470 has switched to another thread and issued 'step'. We need to step over
471 breakpoint in the thread which hit the breakpoint, but then continue
472 stepping the thread user has selected. */
473 static ptid_t deferred_step_ptid;
476 /* Things to clean up if we QUIT out of resume (). */
478 resume_cleanups (void *ignore)
483 static const char schedlock_off[] = "off";
484 static const char schedlock_on[] = "on";
485 static const char schedlock_step[] = "step";
486 static const char *scheduler_enums[] = {
492 static const char *scheduler_mode = schedlock_off;
494 show_scheduler_mode (struct ui_file *file, int from_tty,
495 struct cmd_list_element *c, const char *value)
497 fprintf_filtered (file, _("\
498 Mode for locking scheduler during execution is \"%s\".\n"),
503 set_schedlock_func (char *args, int from_tty, struct cmd_list_element *c)
505 if (!target_can_lock_scheduler)
507 scheduler_mode = schedlock_off;
508 error (_("Target '%s' cannot support this command."), target_shortname);
513 /* Resume the inferior, but allow a QUIT. This is useful if the user
514 wants to interrupt some lengthy single-stepping operation
515 (for child processes, the SIGINT goes to the inferior, and so
516 we get a SIGINT random_signal, but for remote debugging and perhaps
517 other targets, that's not true).
519 STEP nonzero if we should step (zero to continue instead).
520 SIG is the signal to give the inferior (zero for none). */
522 resume (int step, enum target_signal sig)
524 int should_resume = 1;
525 struct cleanup *old_cleanups = make_cleanup (resume_cleanups, 0);
529 fprintf_unfiltered (gdb_stdlog, "infrun: resume (step=%d, signal=%d)\n",
532 /* FIXME: calling breakpoint_here_p (read_pc ()) three times! */
535 /* Some targets (e.g. Solaris x86) have a kernel bug when stepping
536 over an instruction that causes a page fault without triggering
537 a hardware watchpoint. The kernel properly notices that it shouldn't
538 stop, because the hardware watchpoint is not triggered, but it forgets
539 the step request and continues the program normally.
540 Work around the problem by removing hardware watchpoints if a step is
541 requested, GDB will check for a hardware watchpoint trigger after the
543 if (CANNOT_STEP_HW_WATCHPOINTS && step)
544 remove_hw_watchpoints ();
547 /* Normally, by the time we reach `resume', the breakpoints are either
548 removed or inserted, as appropriate. The exception is if we're sitting
549 at a permanent breakpoint; we need to step over it, but permanent
550 breakpoints can't be removed. So we have to test for it here. */
551 if (breakpoint_here_p (read_pc ()) == permanent_breakpoint_here)
553 if (gdbarch_skip_permanent_breakpoint_p (current_gdbarch))
554 gdbarch_skip_permanent_breakpoint (current_gdbarch,
555 get_current_regcache ());
558 The program is stopped at a permanent breakpoint, but GDB does not know\n\
559 how to step past a permanent breakpoint on this architecture. Try using\n\
560 a command like `return' or `jump' to continue execution."));
563 if (step && gdbarch_software_single_step_p (current_gdbarch))
565 /* Do it the hard way, w/temp breakpoints */
566 if (gdbarch_software_single_step (current_gdbarch, get_current_frame ()))
568 /* ...and don't ask hardware to do it. */
570 /* and do not pull these breakpoints until after a `wait' in
571 `wait_for_inferior' */
572 singlestep_breakpoints_inserted_p = 1;
573 singlestep_ptid = inferior_ptid;
574 singlestep_pc = read_pc ();
578 /* If there were any forks/vforks/execs that were caught and are
579 now to be followed, then do so. */
580 switch (pending_follow.kind)
582 case TARGET_WAITKIND_FORKED:
583 case TARGET_WAITKIND_VFORKED:
584 pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
589 case TARGET_WAITKIND_EXECD:
590 /* follow_exec is called as soon as the exec event is seen. */
591 pending_follow.kind = TARGET_WAITKIND_SPURIOUS;
598 /* Install inferior's terminal modes. */
599 target_terminal_inferior ();
605 resume_ptid = RESUME_ALL; /* Default */
607 /* If STEP is set, it's a request to use hardware stepping
608 facilities. But in that case, we should never
609 use singlestep breakpoint. */
610 gdb_assert (!(singlestep_breakpoints_inserted_p && step));
612 if (singlestep_breakpoints_inserted_p
613 && stepping_past_singlestep_breakpoint)
615 /* The situation here is as follows. In thread T1 we wanted to
616 single-step. Lacking hardware single-stepping we've
617 set breakpoint at the PC of the next instruction -- call it
618 P. After resuming, we've hit that breakpoint in thread T2.
619 Now we've removed original breakpoint, inserted breakpoint
620 at P+1, and try to step to advance T2 past breakpoint.
621 We need to step only T2, as if T1 is allowed to freely run,
622 it can run past P, and if other threads are allowed to run,
623 they can hit breakpoint at P+1, and nested hits of single-step
624 breakpoints is not something we'd want -- that's complicated
625 to support, and has no value. */
626 resume_ptid = inferior_ptid;
629 if ((step || singlestep_breakpoints_inserted_p)
630 && breakpoint_here_p (read_pc ())
631 && !breakpoint_inserted_here_p (read_pc ()))
633 /* We're stepping, have breakpoint at PC, and it's
634 not inserted. Most likely, proceed has noticed that
635 we have breakpoint and tries to single-step over it,
636 so that it's not hit. In which case, we need to
637 single-step only this thread, and keep others stopped,
638 as they can miss this breakpoint if allowed to run.
640 The current code either has all breakpoints inserted,
641 or all removed, so if we let other threads run,
642 we can actually miss any breakpoint, not the one at PC. */
643 resume_ptid = inferior_ptid;
646 if ((scheduler_mode == schedlock_on)
647 || (scheduler_mode == schedlock_step
648 && (step || singlestep_breakpoints_inserted_p)))
650 /* User-settable 'scheduler' mode requires solo thread resume. */
651 resume_ptid = inferior_ptid;
654 if (gdbarch_cannot_step_breakpoint (current_gdbarch))
656 /* Most targets can step a breakpoint instruction, thus
657 executing it normally. But if this one cannot, just
658 continue and we will hit it anyway. */
659 if (step && breakpoint_inserted_here_p (read_pc ()))
662 target_resume (resume_ptid, step, sig);
665 discard_cleanups (old_cleanups);
669 /* Clear out all variables saying what to do when inferior is continued.
670 First do this, then set the ones you want, then call `proceed'. */
673 clear_proceed_status (void)
675 stepping_over_breakpoint = 0;
676 step_range_start = 0;
678 step_frame_id = null_frame_id;
679 step_over_calls = STEP_OVER_UNDEBUGGABLE;
681 stop_soon = NO_STOP_QUIETLY;
682 proceed_to_finish = 0;
683 breakpoint_proceeded = 1; /* We're about to proceed... */
687 regcache_xfree (stop_registers);
688 stop_registers = NULL;
691 /* Discard any remaining commands or status from previous stop. */
692 bpstat_clear (&stop_bpstat);
695 /* This should be suitable for any targets that support threads. */
698 prepare_to_proceed (int step)
701 struct target_waitstatus wait_status;
703 /* Get the last target status returned by target_wait(). */
704 get_last_target_status (&wait_ptid, &wait_status);
706 /* Make sure we were stopped at a breakpoint. */
707 if (wait_status.kind != TARGET_WAITKIND_STOPPED
708 || wait_status.value.sig != TARGET_SIGNAL_TRAP)
713 /* Switched over from WAIT_PID. */
714 if (!ptid_equal (wait_ptid, minus_one_ptid)
715 && !ptid_equal (inferior_ptid, wait_ptid)
716 && breakpoint_here_p (read_pc_pid (wait_ptid)))
718 /* If stepping, remember current thread to switch back to. */
721 deferred_step_ptid = inferior_ptid;
724 /* Switch back to WAIT_PID thread. */
725 switch_to_thread (wait_ptid);
727 /* We return 1 to indicate that there is a breakpoint here,
728 so we need to step over it before continuing to avoid
729 hitting it straight away. */
736 /* Record the pc of the program the last time it stopped. This is
737 just used internally by wait_for_inferior, but need to be preserved
738 over calls to it and cleared when the inferior is started. */
739 static CORE_ADDR prev_pc;
741 /* Basic routine for continuing the program in various fashions.
743 ADDR is the address to resume at, or -1 for resume where stopped.
744 SIGGNAL is the signal to give it, or 0 for none,
745 or -1 for act according to how it stopped.
746 STEP is nonzero if should trap after one instruction.
747 -1 means return after that and print nothing.
748 You should probably set various step_... variables
749 before calling here, if you are stepping.
751 You should call clear_proceed_status before calling proceed. */
754 proceed (CORE_ADDR addr, enum target_signal siggnal, int step)
759 step_start_function = find_pc_function (read_pc ());
763 if (addr == (CORE_ADDR) -1)
765 if (read_pc () == stop_pc && breakpoint_here_p (read_pc ()))
766 /* There is a breakpoint at the address we will resume at,
767 step one instruction before inserting breakpoints so that
768 we do not stop right away (and report a second hit at this
771 else if (gdbarch_single_step_through_delay_p (current_gdbarch)
772 && gdbarch_single_step_through_delay (current_gdbarch,
773 get_current_frame ()))
774 /* We stepped onto an instruction that needs to be stepped
775 again before re-inserting the breakpoint, do so. */
784 fprintf_unfiltered (gdb_stdlog,
785 "infrun: proceed (addr=0x%s, signal=%d, step=%d)\n",
786 paddr_nz (addr), siggnal, step);
788 /* In a multi-threaded task we may select another thread
789 and then continue or step.
791 But if the old thread was stopped at a breakpoint, it
792 will immediately cause another breakpoint stop without
793 any execution (i.e. it will report a breakpoint hit
794 incorrectly). So we must step over it first.
796 prepare_to_proceed checks the current thread against the thread
797 that reported the most recent event. If a step-over is required
798 it returns TRUE and sets the current thread to the old thread. */
799 if (prepare_to_proceed (step))
803 /* We will get a trace trap after one instruction.
804 Continue it automatically and insert breakpoints then. */
805 stepping_over_breakpoint = 1;
807 insert_breakpoints ();
809 if (siggnal != TARGET_SIGNAL_DEFAULT)
810 stop_signal = siggnal;
811 /* If this signal should not be seen by program,
812 give it zero. Used for debugging signals. */
813 else if (!signal_program[stop_signal])
814 stop_signal = TARGET_SIGNAL_0;
816 annotate_starting ();
818 /* Make sure that output from GDB appears before output from the
820 gdb_flush (gdb_stdout);
822 /* Refresh prev_pc value just prior to resuming. This used to be
823 done in stop_stepping, however, setting prev_pc there did not handle
824 scenarios such as inferior function calls or returning from
825 a function via the return command. In those cases, the prev_pc
826 value was not set properly for subsequent commands. The prev_pc value
827 is used to initialize the starting line number in the ecs. With an
828 invalid value, the gdb next command ends up stopping at the position
829 represented by the next line table entry past our start position.
830 On platforms that generate one line table entry per line, this
831 is not a problem. However, on the ia64, the compiler generates
832 extraneous line table entries that do not increase the line number.
833 When we issue the gdb next command on the ia64 after an inferior call
834 or a return command, we often end up a few instructions forward, still
835 within the original line we started.
837 An attempt was made to have init_execution_control_state () refresh
838 the prev_pc value before calculating the line number. This approach
839 did not work because on platforms that use ptrace, the pc register
840 cannot be read unless the inferior is stopped. At that point, we
841 are not guaranteed the inferior is stopped and so the read_pc ()
842 call can fail. Setting the prev_pc value here ensures the value is
843 updated correctly when the inferior is stopped. */
844 prev_pc = read_pc ();
846 /* Resume inferior. */
847 resume (oneproc || step || bpstat_should_step (), stop_signal);
849 /* Wait for it to stop (if not standalone)
850 and in any case decode why it stopped, and act accordingly. */
851 /* Do this only if we are not using the event loop, or if the target
852 does not support asynchronous execution. */
853 if (!target_can_async_p ())
855 wait_for_inferior ();
861 /* Start remote-debugging of a machine over a serial link. */
864 start_remote (int from_tty)
867 init_wait_for_inferior ();
868 stop_soon = STOP_QUIETLY_REMOTE;
869 stepping_over_breakpoint = 0;
871 /* Always go on waiting for the target, regardless of the mode. */
872 /* FIXME: cagney/1999-09-23: At present it isn't possible to
873 indicate to wait_for_inferior that a target should timeout if
874 nothing is returned (instead of just blocking). Because of this,
875 targets expecting an immediate response need to, internally, set
876 things up so that the target_wait() is forced to eventually
878 /* FIXME: cagney/1999-09-24: It isn't possible for target_open() to
879 differentiate to its caller what the state of the target is after
880 the initial open has been performed. Here we're assuming that
881 the target has stopped. It should be possible to eventually have
882 target_open() return to the caller an indication that the target
883 is currently running and GDB state should be set to the same as
885 wait_for_inferior ();
887 /* Now that the inferior has stopped, do any bookkeeping like
888 loading shared libraries. We want to do this before normal_stop,
889 so that the displayed frame is up to date. */
890 post_create_inferior (¤t_target, from_tty);
895 /* Initialize static vars when a new inferior begins. */
898 init_wait_for_inferior (void)
900 /* These are meaningless until the first time through wait_for_inferior. */
903 breakpoint_init_inferior (inf_starting);
905 /* Don't confuse first call to proceed(). */
906 stop_signal = TARGET_SIGNAL_0;
908 /* The first resume is not following a fork/vfork/exec. */
909 pending_follow.kind = TARGET_WAITKIND_SPURIOUS; /* I.e., none. */
911 clear_proceed_status ();
913 stepping_past_singlestep_breakpoint = 0;
914 deferred_step_ptid = null_ptid;
917 /* This enum encodes possible reasons for doing a target_wait, so that
918 wfi can call target_wait in one place. (Ultimately the call will be
919 moved out of the infinite loop entirely.) */
923 infwait_normal_state,
924 infwait_thread_hop_state,
925 infwait_step_watch_state,
926 infwait_nonstep_watch_state
929 /* Why did the inferior stop? Used to print the appropriate messages
930 to the interface from within handle_inferior_event(). */
931 enum inferior_stop_reason
933 /* Step, next, nexti, stepi finished. */
935 /* Inferior terminated by signal. */
937 /* Inferior exited. */
939 /* Inferior received signal, and user asked to be notified. */
943 /* This structure contains what used to be local variables in
944 wait_for_inferior. Probably many of them can return to being
945 locals in handle_inferior_event. */
947 struct execution_control_state
949 struct target_waitstatus ws;
950 struct target_waitstatus *wp;
951 /* Should we step over breakpoint next time keep_going
953 int stepping_over_breakpoint;
955 CORE_ADDR stop_func_start;
956 CORE_ADDR stop_func_end;
957 char *stop_func_name;
958 struct symtab_and_line sal;
960 struct symtab *current_symtab;
961 int handling_longjmp; /* FIXME */
963 ptid_t saved_inferior_ptid;
964 int step_after_step_resume_breakpoint;
965 int stepping_through_solib_after_catch;
966 bpstat stepping_through_solib_catchpoints;
967 int new_thread_event;
968 struct target_waitstatus tmpstatus;
969 enum infwait_states infwait_state;
974 void init_execution_control_state (struct execution_control_state *ecs);
976 void handle_inferior_event (struct execution_control_state *ecs);
978 static void step_into_function (struct execution_control_state *ecs);
979 static void insert_step_resume_breakpoint_at_frame (struct frame_info *step_frame);
980 static void insert_step_resume_breakpoint_at_caller (struct frame_info *);
981 static void insert_step_resume_breakpoint_at_sal (struct symtab_and_line sr_sal,
982 struct frame_id sr_id);
983 static void stop_stepping (struct execution_control_state *ecs);
984 static void prepare_to_wait (struct execution_control_state *ecs);
985 static void keep_going (struct execution_control_state *ecs);
986 static void print_stop_reason (enum inferior_stop_reason stop_reason,
989 /* Wait for control to return from inferior to debugger.
990 If inferior gets a signal, we may decide to start it up again
991 instead of returning. That is why there is a loop in this function.
992 When this function actually returns it means the inferior
993 should be left stopped and GDB should read more commands. */
996 wait_for_inferior (void)
998 struct cleanup *old_cleanups;
999 struct execution_control_state ecss;
1000 struct execution_control_state *ecs;
1003 fprintf_unfiltered (gdb_stdlog, "infrun: wait_for_inferior\n");
1005 old_cleanups = make_cleanup (delete_step_resume_breakpoint,
1006 &step_resume_breakpoint);
1008 /* wfi still stays in a loop, so it's OK just to take the address of
1009 a local to get the ecs pointer. */
1012 /* Fill in with reasonable starting values. */
1013 init_execution_control_state (ecs);
1015 /* We'll update this if & when we switch to a new thread. */
1016 previous_inferior_ptid = inferior_ptid;
1018 overlay_cache_invalid = 1;
1020 /* We have to invalidate the registers BEFORE calling target_wait
1021 because they can be loaded from the target while in target_wait.
1022 This makes remote debugging a bit more efficient for those
1023 targets that provide critical registers as part of their normal
1024 status mechanism. */
1026 registers_changed ();
1030 if (deprecated_target_wait_hook)
1031 ecs->ptid = deprecated_target_wait_hook (ecs->waiton_ptid, ecs->wp);
1033 ecs->ptid = target_wait (ecs->waiton_ptid, ecs->wp);
1035 /* Now figure out what to do with the result of the result. */
1036 handle_inferior_event (ecs);
1038 if (!ecs->wait_some_more)
1041 do_cleanups (old_cleanups);
1044 /* Asynchronous version of wait_for_inferior. It is called by the
1045 event loop whenever a change of state is detected on the file
1046 descriptor corresponding to the target. It can be called more than
1047 once to complete a single execution command. In such cases we need
1048 to keep the state in a global variable ASYNC_ECSS. If it is the
1049 last time that this function is called for a single execution
1050 command, then report to the user that the inferior has stopped, and
1051 do the necessary cleanups. */
1053 struct execution_control_state async_ecss;
1054 struct execution_control_state *async_ecs;
1057 fetch_inferior_event (void *client_data)
1059 static struct cleanup *old_cleanups;
1061 async_ecs = &async_ecss;
1063 if (!async_ecs->wait_some_more)
1065 old_cleanups = make_exec_cleanup (delete_step_resume_breakpoint,
1066 &step_resume_breakpoint);
1068 /* Fill in with reasonable starting values. */
1069 init_execution_control_state (async_ecs);
1071 /* We'll update this if & when we switch to a new thread. */
1072 previous_inferior_ptid = inferior_ptid;
1074 overlay_cache_invalid = 1;
1076 /* We have to invalidate the registers BEFORE calling target_wait
1077 because they can be loaded from the target while in target_wait.
1078 This makes remote debugging a bit more efficient for those
1079 targets that provide critical registers as part of their normal
1080 status mechanism. */
1082 registers_changed ();
1085 if (deprecated_target_wait_hook)
1087 deprecated_target_wait_hook (async_ecs->waiton_ptid, async_ecs->wp);
1089 async_ecs->ptid = target_wait (async_ecs->waiton_ptid, async_ecs->wp);
1091 /* Now figure out what to do with the result of the result. */
1092 handle_inferior_event (async_ecs);
1094 if (!async_ecs->wait_some_more)
1096 /* Do only the cleanups that have been added by this
1097 function. Let the continuations for the commands do the rest,
1098 if there are any. */
1099 do_exec_cleanups (old_cleanups);
1101 if (step_multi && stop_step)
1102 inferior_event_handler (INF_EXEC_CONTINUE, NULL);
1104 inferior_event_handler (INF_EXEC_COMPLETE, NULL);
1108 /* Prepare an execution control state for looping through a
1109 wait_for_inferior-type loop. */
1112 init_execution_control_state (struct execution_control_state *ecs)
1114 ecs->stepping_over_breakpoint = 0;
1115 ecs->random_signal = 0;
1116 ecs->step_after_step_resume_breakpoint = 0;
1117 ecs->handling_longjmp = 0; /* FIXME */
1118 ecs->stepping_through_solib_after_catch = 0;
1119 ecs->stepping_through_solib_catchpoints = NULL;
1120 ecs->sal = find_pc_line (prev_pc, 0);
1121 ecs->current_line = ecs->sal.line;
1122 ecs->current_symtab = ecs->sal.symtab;
1123 ecs->infwait_state = infwait_normal_state;
1124 ecs->waiton_ptid = pid_to_ptid (-1);
1125 ecs->wp = &(ecs->ws);
1128 /* Return the cached copy of the last pid/waitstatus returned by
1129 target_wait()/deprecated_target_wait_hook(). The data is actually
1130 cached by handle_inferior_event(), which gets called immediately
1131 after target_wait()/deprecated_target_wait_hook(). */
1134 get_last_target_status (ptid_t *ptidp, struct target_waitstatus *status)
1136 *ptidp = target_last_wait_ptid;
1137 *status = target_last_waitstatus;
1141 nullify_last_target_wait_ptid (void)
1143 target_last_wait_ptid = minus_one_ptid;
1146 /* Switch thread contexts, maintaining "infrun state". */
1149 context_switch (struct execution_control_state *ecs)
1151 /* Caution: it may happen that the new thread (or the old one!)
1152 is not in the thread list. In this case we must not attempt
1153 to "switch context", or we run the risk that our context may
1154 be lost. This may happen as a result of the target module
1155 mishandling thread creation. */
1159 fprintf_unfiltered (gdb_stdlog, "infrun: Switching context from %s ",
1160 target_pid_to_str (inferior_ptid));
1161 fprintf_unfiltered (gdb_stdlog, "to %s\n",
1162 target_pid_to_str (ecs->ptid));
1165 if (in_thread_list (inferior_ptid) && in_thread_list (ecs->ptid))
1166 { /* Perform infrun state context switch: */
1167 /* Save infrun state for the old thread. */
1168 save_infrun_state (inferior_ptid, prev_pc,
1169 stepping_over_breakpoint, step_resume_breakpoint,
1171 step_range_end, &step_frame_id,
1172 ecs->handling_longjmp, ecs->stepping_over_breakpoint,
1173 ecs->stepping_through_solib_after_catch,
1174 ecs->stepping_through_solib_catchpoints,
1175 ecs->current_line, ecs->current_symtab);
1177 /* Load infrun state for the new thread. */
1178 load_infrun_state (ecs->ptid, &prev_pc,
1179 &stepping_over_breakpoint, &step_resume_breakpoint,
1181 &step_range_end, &step_frame_id,
1182 &ecs->handling_longjmp, &ecs->stepping_over_breakpoint,
1183 &ecs->stepping_through_solib_after_catch,
1184 &ecs->stepping_through_solib_catchpoints,
1185 &ecs->current_line, &ecs->current_symtab);
1188 switch_to_thread (ecs->ptid);
1192 adjust_pc_after_break (struct execution_control_state *ecs)
1194 CORE_ADDR breakpoint_pc;
1196 /* If this target does not decrement the PC after breakpoints, then
1197 we have nothing to do. */
1198 if (gdbarch_decr_pc_after_break (current_gdbarch) == 0)
1201 /* If we've hit a breakpoint, we'll normally be stopped with SIGTRAP. If
1202 we aren't, just return.
1204 We assume that waitkinds other than TARGET_WAITKIND_STOPPED are not
1205 affected by gdbarch_decr_pc_after_break. Other waitkinds which are
1206 implemented by software breakpoints should be handled through the normal
1209 NOTE drow/2004-01-31: On some targets, breakpoints may generate
1210 different signals (SIGILL or SIGEMT for instance), but it is less
1211 clear where the PC is pointing afterwards. It may not match
1212 gdbarch_decr_pc_after_break. I don't know any specific target that
1213 generates these signals at breakpoints (the code has been in GDB since at
1214 least 1992) so I can not guess how to handle them here.
1216 In earlier versions of GDB, a target with
1217 gdbarch_have_nonsteppable_watchpoint would have the PC after hitting a
1218 watchpoint affected by gdbarch_decr_pc_after_break. I haven't found any
1219 target with both of these set in GDB history, and it seems unlikely to be
1220 correct, so gdbarch_have_nonsteppable_watchpoint is not checked here. */
1222 if (ecs->ws.kind != TARGET_WAITKIND_STOPPED)
1225 if (ecs->ws.value.sig != TARGET_SIGNAL_TRAP)
1228 /* Find the location where (if we've hit a breakpoint) the
1229 breakpoint would be. */
1230 breakpoint_pc = read_pc_pid (ecs->ptid) - gdbarch_decr_pc_after_break
1233 /* Check whether there actually is a software breakpoint inserted
1234 at that location. */
1235 if (software_breakpoint_inserted_here_p (breakpoint_pc))
1237 /* When using hardware single-step, a SIGTRAP is reported for both
1238 a completed single-step and a software breakpoint. Need to
1239 differentiate between the two, as the latter needs adjusting
1240 but the former does not.
1242 The SIGTRAP can be due to a completed hardware single-step only if
1243 - we didn't insert software single-step breakpoints
1244 - the thread to be examined is still the current thread
1245 - this thread is currently being stepped
1247 If any of these events did not occur, we must have stopped due
1248 to hitting a software breakpoint, and have to back up to the
1251 As a special case, we could have hardware single-stepped a
1252 software breakpoint. In this case (prev_pc == breakpoint_pc),
1253 we also need to back up to the breakpoint address. */
1255 if (singlestep_breakpoints_inserted_p
1256 || !ptid_equal (ecs->ptid, inferior_ptid)
1257 || !currently_stepping (ecs)
1258 || prev_pc == breakpoint_pc)
1259 write_pc_pid (breakpoint_pc, ecs->ptid);
1263 /* Given an execution control state that has been freshly filled in
1264 by an event from the inferior, figure out what it means and take
1265 appropriate action. */
1268 handle_inferior_event (struct execution_control_state *ecs)
1270 int sw_single_step_trap_p = 0;
1271 int stopped_by_watchpoint;
1272 int stepped_after_stopped_by_watchpoint = 0;
1274 /* Cache the last pid/waitstatus. */
1275 target_last_wait_ptid = ecs->ptid;
1276 target_last_waitstatus = *ecs->wp;
1278 adjust_pc_after_break (ecs);
1280 switch (ecs->infwait_state)
1282 case infwait_thread_hop_state:
1284 fprintf_unfiltered (gdb_stdlog, "infrun: infwait_thread_hop_state\n");
1285 /* Cancel the waiton_ptid. */
1286 ecs->waiton_ptid = pid_to_ptid (-1);
1289 case infwait_normal_state:
1291 fprintf_unfiltered (gdb_stdlog, "infrun: infwait_normal_state\n");
1294 case infwait_step_watch_state:
1296 fprintf_unfiltered (gdb_stdlog,
1297 "infrun: infwait_step_watch_state\n");
1299 stepped_after_stopped_by_watchpoint = 1;
1302 case infwait_nonstep_watch_state:
1304 fprintf_unfiltered (gdb_stdlog,
1305 "infrun: infwait_nonstep_watch_state\n");
1306 insert_breakpoints ();
1308 /* FIXME-maybe: is this cleaner than setting a flag? Does it
1309 handle things like signals arriving and other things happening
1310 in combination correctly? */
1311 stepped_after_stopped_by_watchpoint = 1;
1315 internal_error (__FILE__, __LINE__, _("bad switch"));
1317 ecs->infwait_state = infwait_normal_state;
1319 reinit_frame_cache ();
1321 /* If it's a new process, add it to the thread database */
1323 ecs->new_thread_event = (!ptid_equal (ecs->ptid, inferior_ptid)
1324 && !ptid_equal (ecs->ptid, minus_one_ptid)
1325 && !in_thread_list (ecs->ptid));
1327 if (ecs->ws.kind != TARGET_WAITKIND_EXITED
1328 && ecs->ws.kind != TARGET_WAITKIND_SIGNALLED && ecs->new_thread_event)
1330 add_thread (ecs->ptid);
1332 ui_out_text (uiout, "[New ");
1333 ui_out_text (uiout, target_pid_or_tid_to_str (ecs->ptid));
1334 ui_out_text (uiout, "]\n");
1337 switch (ecs->ws.kind)
1339 case TARGET_WAITKIND_LOADED:
1341 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_LOADED\n");
1342 /* Ignore gracefully during startup of the inferior, as it might
1343 be the shell which has just loaded some objects, otherwise
1344 add the symbols for the newly loaded objects. Also ignore at
1345 the beginning of an attach or remote session; we will query
1346 the full list of libraries once the connection is
1348 if (stop_soon == NO_STOP_QUIETLY)
1350 /* Remove breakpoints, SOLIB_ADD might adjust
1351 breakpoint addresses via breakpoint_re_set. */
1352 remove_breakpoints ();
1354 /* Check for any newly added shared libraries if we're
1355 supposed to be adding them automatically. Switch
1356 terminal for any messages produced by
1357 breakpoint_re_set. */
1358 target_terminal_ours_for_output ();
1359 /* NOTE: cagney/2003-11-25: Make certain that the target
1360 stack's section table is kept up-to-date. Architectures,
1361 (e.g., PPC64), use the section table to perform
1362 operations such as address => section name and hence
1363 require the table to contain all sections (including
1364 those found in shared libraries). */
1365 /* NOTE: cagney/2003-11-25: Pass current_target and not
1366 exec_ops to SOLIB_ADD. This is because current GDB is
1367 only tooled to propagate section_table changes out from
1368 the "current_target" (see target_resize_to_sections), and
1369 not up from the exec stratum. This, of course, isn't
1370 right. "infrun.c" should only interact with the
1371 exec/process stratum, instead relying on the target stack
1372 to propagate relevant changes (stop, section table
1373 changed, ...) up to other layers. */
1375 SOLIB_ADD (NULL, 0, ¤t_target, auto_solib_add);
1377 solib_add (NULL, 0, ¤t_target, auto_solib_add);
1379 target_terminal_inferior ();
1381 /* If requested, stop when the dynamic linker notifies
1382 gdb of events. This allows the user to get control
1383 and place breakpoints in initializer routines for
1384 dynamically loaded objects (among other things). */
1385 if (stop_on_solib_events)
1387 stop_stepping (ecs);
1391 /* NOTE drow/2007-05-11: This might be a good place to check
1392 for "catch load". */
1394 /* Reinsert breakpoints and continue. */
1395 insert_breakpoints ();
1398 /* If we are skipping through a shell, or through shared library
1399 loading that we aren't interested in, resume the program. If
1400 we're running the program normally, also resume. But stop if
1401 we're attaching or setting up a remote connection. */
1402 if (stop_soon == STOP_QUIETLY || stop_soon == NO_STOP_QUIETLY)
1404 resume (0, TARGET_SIGNAL_0);
1405 prepare_to_wait (ecs);
1411 case TARGET_WAITKIND_SPURIOUS:
1413 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_SPURIOUS\n");
1414 resume (0, TARGET_SIGNAL_0);
1415 prepare_to_wait (ecs);
1418 case TARGET_WAITKIND_EXITED:
1420 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_EXITED\n");
1421 target_terminal_ours (); /* Must do this before mourn anyway */
1422 print_stop_reason (EXITED, ecs->ws.value.integer);
1424 /* Record the exit code in the convenience variable $_exitcode, so
1425 that the user can inspect this again later. */
1426 set_internalvar (lookup_internalvar ("_exitcode"),
1427 value_from_longest (builtin_type_int,
1428 (LONGEST) ecs->ws.value.integer));
1429 gdb_flush (gdb_stdout);
1430 target_mourn_inferior ();
1431 singlestep_breakpoints_inserted_p = 0;
1432 stop_print_frame = 0;
1433 stop_stepping (ecs);
1436 case TARGET_WAITKIND_SIGNALLED:
1438 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_SIGNALLED\n");
1439 stop_print_frame = 0;
1440 stop_signal = ecs->ws.value.sig;
1441 target_terminal_ours (); /* Must do this before mourn anyway */
1443 /* Note: By definition of TARGET_WAITKIND_SIGNALLED, we shouldn't
1444 reach here unless the inferior is dead. However, for years
1445 target_kill() was called here, which hints that fatal signals aren't
1446 really fatal on some systems. If that's true, then some changes
1448 target_mourn_inferior ();
1450 print_stop_reason (SIGNAL_EXITED, stop_signal);
1451 singlestep_breakpoints_inserted_p = 0;
1452 stop_stepping (ecs);
1455 /* The following are the only cases in which we keep going;
1456 the above cases end in a continue or goto. */
1457 case TARGET_WAITKIND_FORKED:
1458 case TARGET_WAITKIND_VFORKED:
1460 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_FORKED\n");
1461 stop_signal = TARGET_SIGNAL_TRAP;
1462 pending_follow.kind = ecs->ws.kind;
1464 pending_follow.fork_event.parent_pid = PIDGET (ecs->ptid);
1465 pending_follow.fork_event.child_pid = ecs->ws.value.related_pid;
1467 if (!ptid_equal (ecs->ptid, inferior_ptid))
1469 context_switch (ecs);
1470 reinit_frame_cache ();
1473 stop_pc = read_pc ();
1475 stop_bpstat = bpstat_stop_status (stop_pc, ecs->ptid);
1477 ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
1479 /* If no catchpoint triggered for this, then keep going. */
1480 if (ecs->random_signal)
1482 stop_signal = TARGET_SIGNAL_0;
1486 goto process_event_stop_test;
1488 case TARGET_WAITKIND_EXECD:
1490 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_EXECD\n");
1491 stop_signal = TARGET_SIGNAL_TRAP;
1493 /* NOTE drow/2002-12-05: This code should be pushed down into the
1494 target_wait function. Until then following vfork on HP/UX 10.20
1495 is probably broken by this. Of course, it's broken anyway. */
1496 /* Is this a target which reports multiple exec events per actual
1497 call to exec()? (HP-UX using ptrace does, for example.) If so,
1498 ignore all but the last one. Just resume the exec'r, and wait
1499 for the next exec event. */
1500 if (inferior_ignoring_leading_exec_events)
1502 inferior_ignoring_leading_exec_events--;
1503 target_resume (ecs->ptid, 0, TARGET_SIGNAL_0);
1504 prepare_to_wait (ecs);
1507 inferior_ignoring_leading_exec_events =
1508 target_reported_exec_events_per_exec_call () - 1;
1510 pending_follow.execd_pathname =
1511 savestring (ecs->ws.value.execd_pathname,
1512 strlen (ecs->ws.value.execd_pathname));
1514 /* This causes the eventpoints and symbol table to be reset. Must
1515 do this now, before trying to determine whether to stop. */
1516 follow_exec (PIDGET (inferior_ptid), pending_follow.execd_pathname);
1517 xfree (pending_follow.execd_pathname);
1519 stop_pc = read_pc_pid (ecs->ptid);
1520 ecs->saved_inferior_ptid = inferior_ptid;
1521 inferior_ptid = ecs->ptid;
1523 stop_bpstat = bpstat_stop_status (stop_pc, ecs->ptid);
1525 ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
1526 inferior_ptid = ecs->saved_inferior_ptid;
1528 if (!ptid_equal (ecs->ptid, inferior_ptid))
1530 context_switch (ecs);
1531 reinit_frame_cache ();
1534 /* If no catchpoint triggered for this, then keep going. */
1535 if (ecs->random_signal)
1537 stop_signal = TARGET_SIGNAL_0;
1541 goto process_event_stop_test;
1543 /* Be careful not to try to gather much state about a thread
1544 that's in a syscall. It's frequently a losing proposition. */
1545 case TARGET_WAITKIND_SYSCALL_ENTRY:
1547 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_SYSCALL_ENTRY\n");
1548 resume (0, TARGET_SIGNAL_0);
1549 prepare_to_wait (ecs);
1552 /* Before examining the threads further, step this thread to
1553 get it entirely out of the syscall. (We get notice of the
1554 event when the thread is just on the verge of exiting a
1555 syscall. Stepping one instruction seems to get it back
1557 case TARGET_WAITKIND_SYSCALL_RETURN:
1559 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_SYSCALL_RETURN\n");
1560 target_resume (ecs->ptid, 1, TARGET_SIGNAL_0);
1561 prepare_to_wait (ecs);
1564 case TARGET_WAITKIND_STOPPED:
1566 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_STOPPED\n");
1567 stop_signal = ecs->ws.value.sig;
1570 /* We had an event in the inferior, but we are not interested
1571 in handling it at this level. The lower layers have already
1572 done what needs to be done, if anything.
1574 One of the possible circumstances for this is when the
1575 inferior produces output for the console. The inferior has
1576 not stopped, and we are ignoring the event. Another possible
1577 circumstance is any event which the lower level knows will be
1578 reported multiple times without an intervening resume. */
1579 case TARGET_WAITKIND_IGNORE:
1581 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_IGNORE\n");
1582 prepare_to_wait (ecs);
1586 /* We may want to consider not doing a resume here in order to give
1587 the user a chance to play with the new thread. It might be good
1588 to make that a user-settable option. */
1590 /* At this point, all threads are stopped (happens automatically in
1591 either the OS or the native code). Therefore we need to continue
1592 all threads in order to make progress. */
1593 if (ecs->new_thread_event)
1595 target_resume (RESUME_ALL, 0, TARGET_SIGNAL_0);
1596 prepare_to_wait (ecs);
1600 stop_pc = read_pc_pid (ecs->ptid);
1603 fprintf_unfiltered (gdb_stdlog, "infrun: stop_pc = 0x%s\n", paddr_nz (stop_pc));
1605 if (stepping_past_singlestep_breakpoint)
1607 gdb_assert (singlestep_breakpoints_inserted_p);
1608 gdb_assert (ptid_equal (singlestep_ptid, ecs->ptid));
1609 gdb_assert (!ptid_equal (singlestep_ptid, saved_singlestep_ptid));
1611 stepping_past_singlestep_breakpoint = 0;
1613 /* We've either finished single-stepping past the single-step
1614 breakpoint, or stopped for some other reason. It would be nice if
1615 we could tell, but we can't reliably. */
1616 if (stop_signal == TARGET_SIGNAL_TRAP)
1619 fprintf_unfiltered (gdb_stdlog, "infrun: stepping_past_singlestep_breakpoint\n");
1620 /* Pull the single step breakpoints out of the target. */
1621 remove_single_step_breakpoints ();
1622 singlestep_breakpoints_inserted_p = 0;
1624 ecs->random_signal = 0;
1626 ecs->ptid = saved_singlestep_ptid;
1627 context_switch (ecs);
1628 if (deprecated_context_hook)
1629 deprecated_context_hook (pid_to_thread_id (ecs->ptid));
1631 resume (1, TARGET_SIGNAL_0);
1632 prepare_to_wait (ecs);
1637 stepping_past_singlestep_breakpoint = 0;
1639 if (!ptid_equal (deferred_step_ptid, null_ptid))
1641 /* If we stopped for some other reason than single-stepping, ignore
1642 the fact that we were supposed to switch back. */
1643 if (stop_signal == TARGET_SIGNAL_TRAP)
1646 fprintf_unfiltered (gdb_stdlog,
1647 "infrun: handling deferred step\n");
1649 /* Pull the single step breakpoints out of the target. */
1650 if (singlestep_breakpoints_inserted_p)
1652 remove_single_step_breakpoints ();
1653 singlestep_breakpoints_inserted_p = 0;
1656 /* Note: We do not call context_switch at this point, as the
1657 context is already set up for stepping the original thread. */
1658 switch_to_thread (deferred_step_ptid);
1659 deferred_step_ptid = null_ptid;
1660 /* Suppress spurious "Switching to ..." message. */
1661 previous_inferior_ptid = inferior_ptid;
1663 resume (1, TARGET_SIGNAL_0);
1664 prepare_to_wait (ecs);
1668 deferred_step_ptid = null_ptid;
1671 /* See if a thread hit a thread-specific breakpoint that was meant for
1672 another thread. If so, then step that thread past the breakpoint,
1675 if (stop_signal == TARGET_SIGNAL_TRAP)
1677 int thread_hop_needed = 0;
1679 /* Check if a regular breakpoint has been hit before checking
1680 for a potential single step breakpoint. Otherwise, GDB will
1681 not see this breakpoint hit when stepping onto breakpoints. */
1682 if (regular_breakpoint_inserted_here_p (stop_pc))
1684 ecs->random_signal = 0;
1685 if (!breakpoint_thread_match (stop_pc, ecs->ptid))
1686 thread_hop_needed = 1;
1688 else if (singlestep_breakpoints_inserted_p)
1690 /* We have not context switched yet, so this should be true
1691 no matter which thread hit the singlestep breakpoint. */
1692 gdb_assert (ptid_equal (inferior_ptid, singlestep_ptid));
1694 fprintf_unfiltered (gdb_stdlog, "infrun: software single step "
1696 target_pid_to_str (ecs->ptid));
1698 ecs->random_signal = 0;
1699 /* The call to in_thread_list is necessary because PTIDs sometimes
1700 change when we go from single-threaded to multi-threaded. If
1701 the singlestep_ptid is still in the list, assume that it is
1702 really different from ecs->ptid. */
1703 if (!ptid_equal (singlestep_ptid, ecs->ptid)
1704 && in_thread_list (singlestep_ptid))
1706 /* If the PC of the thread we were trying to single-step
1707 has changed, discard this event (which we were going
1708 to ignore anyway), and pretend we saw that thread
1709 trap. This prevents us continuously moving the
1710 single-step breakpoint forward, one instruction at a
1711 time. If the PC has changed, then the thread we were
1712 trying to single-step has trapped or been signalled,
1713 but the event has not been reported to GDB yet.
1715 There might be some cases where this loses signal
1716 information, if a signal has arrived at exactly the
1717 same time that the PC changed, but this is the best
1718 we can do with the information available. Perhaps we
1719 should arrange to report all events for all threads
1720 when they stop, or to re-poll the remote looking for
1721 this particular thread (i.e. temporarily enable
1723 if (read_pc_pid (singlestep_ptid) != singlestep_pc)
1726 fprintf_unfiltered (gdb_stdlog, "infrun: unexpected thread,"
1727 " but expected thread advanced also\n");
1729 /* The current context still belongs to
1730 singlestep_ptid. Don't swap here, since that's
1731 the context we want to use. Just fudge our
1732 state and continue. */
1733 ecs->ptid = singlestep_ptid;
1734 stop_pc = read_pc_pid (ecs->ptid);
1739 fprintf_unfiltered (gdb_stdlog,
1740 "infrun: unexpected thread\n");
1742 thread_hop_needed = 1;
1743 stepping_past_singlestep_breakpoint = 1;
1744 saved_singlestep_ptid = singlestep_ptid;
1749 if (thread_hop_needed)
1754 fprintf_unfiltered (gdb_stdlog, "infrun: thread_hop_needed\n");
1756 /* Saw a breakpoint, but it was hit by the wrong thread.
1759 if (singlestep_breakpoints_inserted_p)
1761 /* Pull the single step breakpoints out of the target. */
1762 remove_single_step_breakpoints ();
1763 singlestep_breakpoints_inserted_p = 0;
1766 remove_status = remove_breakpoints ();
1767 /* Did we fail to remove breakpoints? If so, try
1768 to set the PC past the bp. (There's at least
1769 one situation in which we can fail to remove
1770 the bp's: On HP-UX's that use ttrace, we can't
1771 change the address space of a vforking child
1772 process until the child exits (well, okay, not
1773 then either :-) or execs. */
1774 if (remove_status != 0)
1776 /* FIXME! This is obviously non-portable! */
1777 write_pc_pid (stop_pc + 4, ecs->ptid);
1778 /* We need to restart all the threads now,
1779 * unles we're running in scheduler-locked mode.
1780 * Use currently_stepping to determine whether to
1783 /* FIXME MVS: is there any reason not to call resume()? */
1784 if (scheduler_mode == schedlock_on)
1785 target_resume (ecs->ptid,
1786 currently_stepping (ecs), TARGET_SIGNAL_0);
1788 target_resume (RESUME_ALL,
1789 currently_stepping (ecs), TARGET_SIGNAL_0);
1790 prepare_to_wait (ecs);
1795 if (!ptid_equal (inferior_ptid, ecs->ptid))
1796 context_switch (ecs);
1797 ecs->waiton_ptid = ecs->ptid;
1798 ecs->wp = &(ecs->ws);
1799 ecs->stepping_over_breakpoint = 1;
1801 ecs->infwait_state = infwait_thread_hop_state;
1803 registers_changed ();
1807 else if (singlestep_breakpoints_inserted_p)
1809 sw_single_step_trap_p = 1;
1810 ecs->random_signal = 0;
1814 ecs->random_signal = 1;
1816 /* See if something interesting happened to the non-current thread. If
1817 so, then switch to that thread. */
1818 if (!ptid_equal (ecs->ptid, inferior_ptid))
1821 fprintf_unfiltered (gdb_stdlog, "infrun: context switch\n");
1823 context_switch (ecs);
1825 if (deprecated_context_hook)
1826 deprecated_context_hook (pid_to_thread_id (ecs->ptid));
1829 if (singlestep_breakpoints_inserted_p)
1831 /* Pull the single step breakpoints out of the target. */
1832 remove_single_step_breakpoints ();
1833 singlestep_breakpoints_inserted_p = 0;
1836 if (stepped_after_stopped_by_watchpoint)
1837 stopped_by_watchpoint = 0;
1839 stopped_by_watchpoint = watchpoints_triggered (&ecs->ws);
1841 /* If necessary, step over this watchpoint. We'll be back to display
1843 if (stopped_by_watchpoint
1844 && (HAVE_STEPPABLE_WATCHPOINT
1845 || gdbarch_have_nonsteppable_watchpoint (current_gdbarch)))
1848 fprintf_unfiltered (gdb_stdlog, "infrun: STOPPED_BY_WATCHPOINT\n");
1850 /* At this point, we are stopped at an instruction which has
1851 attempted to write to a piece of memory under control of
1852 a watchpoint. The instruction hasn't actually executed
1853 yet. If we were to evaluate the watchpoint expression
1854 now, we would get the old value, and therefore no change
1855 would seem to have occurred.
1857 In order to make watchpoints work `right', we really need
1858 to complete the memory write, and then evaluate the
1859 watchpoint expression. We do this by single-stepping the
1862 It may not be necessary to disable the watchpoint to stop over
1863 it. For example, the PA can (with some kernel cooperation)
1864 single step over a watchpoint without disabling the watchpoint.
1866 It is far more common to need to disable a watchpoint to step
1867 the inferior over it. If we have non-steppable watchpoints,
1868 we must disable the current watchpoint; it's simplest to
1869 disable all watchpoints and breakpoints. */
1871 if (!HAVE_STEPPABLE_WATCHPOINT)
1872 remove_breakpoints ();
1873 registers_changed ();
1874 target_resume (ecs->ptid, 1, TARGET_SIGNAL_0); /* Single step */
1875 ecs->waiton_ptid = ecs->ptid;
1876 if (HAVE_STEPPABLE_WATCHPOINT)
1877 ecs->infwait_state = infwait_step_watch_state;
1879 ecs->infwait_state = infwait_nonstep_watch_state;
1880 prepare_to_wait (ecs);
1884 ecs->stop_func_start = 0;
1885 ecs->stop_func_end = 0;
1886 ecs->stop_func_name = 0;
1887 /* Don't care about return value; stop_func_start and stop_func_name
1888 will both be 0 if it doesn't work. */
1889 find_pc_partial_function (stop_pc, &ecs->stop_func_name,
1890 &ecs->stop_func_start, &ecs->stop_func_end);
1891 ecs->stop_func_start
1892 += gdbarch_deprecated_function_start_offset (current_gdbarch);
1893 ecs->stepping_over_breakpoint = 0;
1894 bpstat_clear (&stop_bpstat);
1896 stop_stack_dummy = 0;
1897 stop_print_frame = 1;
1898 ecs->random_signal = 0;
1899 stopped_by_random_signal = 0;
1901 if (stop_signal == TARGET_SIGNAL_TRAP
1902 && stepping_over_breakpoint
1903 && gdbarch_single_step_through_delay_p (current_gdbarch)
1904 && currently_stepping (ecs))
1906 /* We're trying to step of a breakpoint. Turns out that we're
1907 also on an instruction that needs to be stepped multiple
1908 times before it's been fully executing. E.g., architectures
1909 with a delay slot. It needs to be stepped twice, once for
1910 the instruction and once for the delay slot. */
1911 int step_through_delay
1912 = gdbarch_single_step_through_delay (current_gdbarch,
1913 get_current_frame ());
1914 if (debug_infrun && step_through_delay)
1915 fprintf_unfiltered (gdb_stdlog, "infrun: step through delay\n");
1916 if (step_range_end == 0 && step_through_delay)
1918 /* The user issued a continue when stopped at a breakpoint.
1919 Set up for another trap and get out of here. */
1920 ecs->stepping_over_breakpoint = 1;
1924 else if (step_through_delay)
1926 /* The user issued a step when stopped at a breakpoint.
1927 Maybe we should stop, maybe we should not - the delay
1928 slot *might* correspond to a line of source. In any
1929 case, don't decide that here, just set
1930 ecs->stepping_over_breakpoint, making sure we
1931 single-step again before breakpoints are re-inserted. */
1932 ecs->stepping_over_breakpoint = 1;
1936 /* Look at the cause of the stop, and decide what to do.
1937 The alternatives are:
1938 1) break; to really stop and return to the debugger,
1939 2) drop through to start up again
1940 (set ecs->stepping_over_breakpoint to 1 to single step once)
1941 3) set ecs->random_signal to 1, and the decision between 1 and 2
1942 will be made according to the signal handling tables. */
1944 /* First, distinguish signals caused by the debugger from signals
1945 that have to do with the program's own actions. Note that
1946 breakpoint insns may cause SIGTRAP or SIGILL or SIGEMT, depending
1947 on the operating system version. Here we detect when a SIGILL or
1948 SIGEMT is really a breakpoint and change it to SIGTRAP. We do
1949 something similar for SIGSEGV, since a SIGSEGV will be generated
1950 when we're trying to execute a breakpoint instruction on a
1951 non-executable stack. This happens for call dummy breakpoints
1952 for architectures like SPARC that place call dummies on the
1955 if (stop_signal == TARGET_SIGNAL_TRAP
1956 || (breakpoint_inserted_here_p (stop_pc)
1957 && (stop_signal == TARGET_SIGNAL_ILL
1958 || stop_signal == TARGET_SIGNAL_SEGV
1959 || stop_signal == TARGET_SIGNAL_EMT))
1960 || stop_soon == STOP_QUIETLY || stop_soon == STOP_QUIETLY_NO_SIGSTOP
1961 || stop_soon == STOP_QUIETLY_REMOTE)
1963 if (stop_signal == TARGET_SIGNAL_TRAP && stop_after_trap)
1966 fprintf_unfiltered (gdb_stdlog, "infrun: stopped\n");
1967 stop_print_frame = 0;
1968 stop_stepping (ecs);
1972 /* This is originated from start_remote(), start_inferior() and
1973 shared libraries hook functions. */
1974 if (stop_soon == STOP_QUIETLY || stop_soon == STOP_QUIETLY_REMOTE)
1977 fprintf_unfiltered (gdb_stdlog, "infrun: quietly stopped\n");
1978 stop_stepping (ecs);
1982 /* This originates from attach_command(). We need to overwrite
1983 the stop_signal here, because some kernels don't ignore a
1984 SIGSTOP in a subsequent ptrace(PTRACE_SONT,SOGSTOP) call.
1985 See more comments in inferior.h. */
1986 if (stop_soon == STOP_QUIETLY_NO_SIGSTOP)
1988 stop_stepping (ecs);
1989 if (stop_signal == TARGET_SIGNAL_STOP)
1990 stop_signal = TARGET_SIGNAL_0;
1994 /* See if there is a breakpoint at the current PC. */
1995 stop_bpstat = bpstat_stop_status (stop_pc, ecs->ptid);
1997 /* Following in case break condition called a
1999 stop_print_frame = 1;
2001 /* NOTE: cagney/2003-03-29: These two checks for a random signal
2002 at one stage in the past included checks for an inferior
2003 function call's call dummy's return breakpoint. The original
2004 comment, that went with the test, read:
2006 ``End of a stack dummy. Some systems (e.g. Sony news) give
2007 another signal besides SIGTRAP, so check here as well as
2010 If someone ever tries to get get call dummys on a
2011 non-executable stack to work (where the target would stop
2012 with something like a SIGSEGV), then those tests might need
2013 to be re-instated. Given, however, that the tests were only
2014 enabled when momentary breakpoints were not being used, I
2015 suspect that it won't be the case.
2017 NOTE: kettenis/2004-02-05: Indeed such checks don't seem to
2018 be necessary for call dummies on a non-executable stack on
2021 if (stop_signal == TARGET_SIGNAL_TRAP)
2023 = !(bpstat_explains_signal (stop_bpstat)
2024 || stepping_over_breakpoint
2025 || (step_range_end && step_resume_breakpoint == NULL));
2028 ecs->random_signal = !bpstat_explains_signal (stop_bpstat);
2029 if (!ecs->random_signal)
2030 stop_signal = TARGET_SIGNAL_TRAP;
2034 /* When we reach this point, we've pretty much decided
2035 that the reason for stopping must've been a random
2036 (unexpected) signal. */
2039 ecs->random_signal = 1;
2041 process_event_stop_test:
2042 /* For the program's own signals, act according to
2043 the signal handling tables. */
2045 if (ecs->random_signal)
2047 /* Signal not for debugging purposes. */
2051 fprintf_unfiltered (gdb_stdlog, "infrun: random signal %d\n", stop_signal);
2053 stopped_by_random_signal = 1;
2055 if (signal_print[stop_signal])
2058 target_terminal_ours_for_output ();
2059 print_stop_reason (SIGNAL_RECEIVED, stop_signal);
2061 if (signal_stop[stop_signal])
2063 stop_stepping (ecs);
2066 /* If not going to stop, give terminal back
2067 if we took it away. */
2069 target_terminal_inferior ();
2071 /* Clear the signal if it should not be passed. */
2072 if (signal_program[stop_signal] == 0)
2073 stop_signal = TARGET_SIGNAL_0;
2075 if (prev_pc == read_pc ()
2076 && breakpoint_here_p (read_pc ())
2077 && !breakpoint_inserted_here_p (read_pc ())
2078 && step_resume_breakpoint == NULL)
2080 /* We were just starting a new sequence, attempting to
2081 single-step off of a breakpoint and expecting a SIGTRAP.
2082 Intead this signal arrives. This signal will take us out
2083 of the stepping range so GDB needs to remember to, when
2084 the signal handler returns, resume stepping off that
2086 /* To simplify things, "continue" is forced to use the same
2087 code paths as single-step - set a breakpoint at the
2088 signal return address and then, once hit, step off that
2091 insert_step_resume_breakpoint_at_frame (get_current_frame ());
2092 ecs->step_after_step_resume_breakpoint = 1;
2097 if (step_range_end != 0
2098 && stop_signal != TARGET_SIGNAL_0
2099 && stop_pc >= step_range_start && stop_pc < step_range_end
2100 && frame_id_eq (get_frame_id (get_current_frame ()),
2102 && step_resume_breakpoint == NULL)
2104 /* The inferior is about to take a signal that will take it
2105 out of the single step range. Set a breakpoint at the
2106 current PC (which is presumably where the signal handler
2107 will eventually return) and then allow the inferior to
2110 Note that this is only needed for a signal delivered
2111 while in the single-step range. Nested signals aren't a
2112 problem as they eventually all return. */
2113 insert_step_resume_breakpoint_at_frame (get_current_frame ());
2118 /* Note: step_resume_breakpoint may be non-NULL. This occures
2119 when either there's a nested signal, or when there's a
2120 pending signal enabled just as the signal handler returns
2121 (leaving the inferior at the step-resume-breakpoint without
2122 actually executing it). Either way continue until the
2123 breakpoint is really hit. */
2128 /* Handle cases caused by hitting a breakpoint. */
2130 CORE_ADDR jmp_buf_pc;
2131 struct bpstat_what what;
2133 what = bpstat_what (stop_bpstat);
2135 if (what.call_dummy)
2137 stop_stack_dummy = 1;
2140 switch (what.main_action)
2142 case BPSTAT_WHAT_SET_LONGJMP_RESUME:
2143 /* If we hit the breakpoint at longjmp, disable it for the
2144 duration of this command. Then, install a temporary
2145 breakpoint at the target of the jmp_buf. */
2147 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_SET_LONGJMP_RESUME\n");
2148 disable_longjmp_breakpoint ();
2149 remove_breakpoints ();
2150 if (!gdbarch_get_longjmp_target_p (current_gdbarch)
2151 || !gdbarch_get_longjmp_target (current_gdbarch,
2152 get_current_frame (), &jmp_buf_pc))
2158 /* Need to blow away step-resume breakpoint, as it
2159 interferes with us */
2160 if (step_resume_breakpoint != NULL)
2162 delete_step_resume_breakpoint (&step_resume_breakpoint);
2165 set_longjmp_resume_breakpoint (jmp_buf_pc, null_frame_id);
2166 ecs->handling_longjmp = 1; /* FIXME */
2170 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME:
2171 case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME_SINGLE:
2173 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_CLEAR_LONGJMP_RESUME\n");
2174 remove_breakpoints ();
2175 disable_longjmp_breakpoint ();
2176 ecs->handling_longjmp = 0; /* FIXME */
2177 if (what.main_action == BPSTAT_WHAT_CLEAR_LONGJMP_RESUME)
2179 /* else fallthrough */
2181 case BPSTAT_WHAT_SINGLE:
2183 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_SINGLE\n");
2184 remove_breakpoints ();
2185 ecs->stepping_over_breakpoint = 1;
2186 /* Still need to check other stuff, at least the case
2187 where we are stepping and step out of the right range. */
2190 case BPSTAT_WHAT_STOP_NOISY:
2192 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STOP_NOISY\n");
2193 stop_print_frame = 1;
2195 /* We are about to nuke the step_resume_breakpointt via the
2196 cleanup chain, so no need to worry about it here. */
2198 stop_stepping (ecs);
2201 case BPSTAT_WHAT_STOP_SILENT:
2203 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STOP_SILENT\n");
2204 stop_print_frame = 0;
2206 /* We are about to nuke the step_resume_breakpoin via the
2207 cleanup chain, so no need to worry about it here. */
2209 stop_stepping (ecs);
2212 case BPSTAT_WHAT_STEP_RESUME:
2213 /* This proably demands a more elegant solution, but, yeah
2216 This function's use of the simple variable
2217 step_resume_breakpoint doesn't seem to accomodate
2218 simultaneously active step-resume bp's, although the
2219 breakpoint list certainly can.
2221 If we reach here and step_resume_breakpoint is already
2222 NULL, then apparently we have multiple active
2223 step-resume bp's. We'll just delete the breakpoint we
2224 stopped at, and carry on.
2226 Correction: what the code currently does is delete a
2227 step-resume bp, but it makes no effort to ensure that
2228 the one deleted is the one currently stopped at. MVS */
2231 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_STEP_RESUME\n");
2233 if (step_resume_breakpoint == NULL)
2235 step_resume_breakpoint =
2236 bpstat_find_step_resume_breakpoint (stop_bpstat);
2238 delete_step_resume_breakpoint (&step_resume_breakpoint);
2239 if (ecs->step_after_step_resume_breakpoint)
2241 /* Back when the step-resume breakpoint was inserted, we
2242 were trying to single-step off a breakpoint. Go back
2244 ecs->step_after_step_resume_breakpoint = 0;
2245 remove_breakpoints ();
2246 ecs->stepping_over_breakpoint = 1;
2252 case BPSTAT_WHAT_CHECK_SHLIBS:
2253 case BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK:
2256 fprintf_unfiltered (gdb_stdlog, "infrun: BPSTAT_WHAT_CHECK_SHLIBS\n");
2257 /* Remove breakpoints, we eventually want to step over the
2258 shlib event breakpoint, and SOLIB_ADD might adjust
2259 breakpoint addresses via breakpoint_re_set. */
2260 remove_breakpoints ();
2262 /* Check for any newly added shared libraries if we're
2263 supposed to be adding them automatically. Switch
2264 terminal for any messages produced by
2265 breakpoint_re_set. */
2266 target_terminal_ours_for_output ();
2267 /* NOTE: cagney/2003-11-25: Make certain that the target
2268 stack's section table is kept up-to-date. Architectures,
2269 (e.g., PPC64), use the section table to perform
2270 operations such as address => section name and hence
2271 require the table to contain all sections (including
2272 those found in shared libraries). */
2273 /* NOTE: cagney/2003-11-25: Pass current_target and not
2274 exec_ops to SOLIB_ADD. This is because current GDB is
2275 only tooled to propagate section_table changes out from
2276 the "current_target" (see target_resize_to_sections), and
2277 not up from the exec stratum. This, of course, isn't
2278 right. "infrun.c" should only interact with the
2279 exec/process stratum, instead relying on the target stack
2280 to propagate relevant changes (stop, section table
2281 changed, ...) up to other layers. */
2283 SOLIB_ADD (NULL, 0, ¤t_target, auto_solib_add);
2285 solib_add (NULL, 0, ¤t_target, auto_solib_add);
2287 target_terminal_inferior ();
2289 /* If requested, stop when the dynamic linker notifies
2290 gdb of events. This allows the user to get control
2291 and place breakpoints in initializer routines for
2292 dynamically loaded objects (among other things). */
2293 if (stop_on_solib_events || stop_stack_dummy)
2295 stop_stepping (ecs);
2299 /* If we stopped due to an explicit catchpoint, then the
2300 (see above) call to SOLIB_ADD pulled in any symbols
2301 from a newly-loaded library, if appropriate.
2303 We do want the inferior to stop, but not where it is
2304 now, which is in the dynamic linker callback. Rather,
2305 we would like it stop in the user's program, just after
2306 the call that caused this catchpoint to trigger. That
2307 gives the user a more useful vantage from which to
2308 examine their program's state. */
2309 else if (what.main_action
2310 == BPSTAT_WHAT_CHECK_SHLIBS_RESUME_FROM_HOOK)
2312 /* ??rehrauer: If I could figure out how to get the
2313 right return PC from here, we could just set a temp
2314 breakpoint and resume. I'm not sure we can without
2315 cracking open the dld's shared libraries and sniffing
2316 their unwind tables and text/data ranges, and that's
2317 not a terribly portable notion.
2319 Until that time, we must step the inferior out of the
2320 dld callback, and also out of the dld itself (and any
2321 code or stubs in libdld.sl, such as "shl_load" and
2322 friends) until we reach non-dld code. At that point,
2323 we can stop stepping. */
2324 bpstat_get_triggered_catchpoints (stop_bpstat,
2326 stepping_through_solib_catchpoints);
2327 ecs->stepping_through_solib_after_catch = 1;
2329 /* Be sure to lift all breakpoints, so the inferior does
2330 actually step past this point... */
2331 ecs->stepping_over_breakpoint = 1;
2336 /* We want to step over this breakpoint, then keep going. */
2337 ecs->stepping_over_breakpoint = 1;
2343 case BPSTAT_WHAT_LAST:
2344 /* Not a real code, but listed here to shut up gcc -Wall. */
2346 case BPSTAT_WHAT_KEEP_CHECKING:
2351 /* We come here if we hit a breakpoint but should not
2352 stop for it. Possibly we also were stepping
2353 and should stop for that. So fall through and
2354 test for stepping. But, if not stepping,
2357 /* Are we stepping to get the inferior out of the dynamic linker's
2358 hook (and possibly the dld itself) after catching a shlib
2360 if (ecs->stepping_through_solib_after_catch)
2362 #if defined(SOLIB_ADD)
2363 /* Have we reached our destination? If not, keep going. */
2364 if (SOLIB_IN_DYNAMIC_LINKER (PIDGET (ecs->ptid), stop_pc))
2367 fprintf_unfiltered (gdb_stdlog, "infrun: stepping in dynamic linker\n");
2368 ecs->stepping_over_breakpoint = 1;
2374 fprintf_unfiltered (gdb_stdlog, "infrun: step past dynamic linker\n");
2375 /* Else, stop and report the catchpoint(s) whose triggering
2376 caused us to begin stepping. */
2377 ecs->stepping_through_solib_after_catch = 0;
2378 bpstat_clear (&stop_bpstat);
2379 stop_bpstat = bpstat_copy (ecs->stepping_through_solib_catchpoints);
2380 bpstat_clear (&ecs->stepping_through_solib_catchpoints);
2381 stop_print_frame = 1;
2382 stop_stepping (ecs);
2386 if (step_resume_breakpoint)
2389 fprintf_unfiltered (gdb_stdlog,
2390 "infrun: step-resume breakpoint is inserted\n");
2392 /* Having a step-resume breakpoint overrides anything
2393 else having to do with stepping commands until
2394 that breakpoint is reached. */
2399 if (step_range_end == 0)
2402 fprintf_unfiltered (gdb_stdlog, "infrun: no stepping, continue\n");
2403 /* Likewise if we aren't even stepping. */
2408 /* If stepping through a line, keep going if still within it.
2410 Note that step_range_end is the address of the first instruction
2411 beyond the step range, and NOT the address of the last instruction
2413 if (stop_pc >= step_range_start && stop_pc < step_range_end)
2416 fprintf_unfiltered (gdb_stdlog, "infrun: stepping inside range [0x%s-0x%s]\n",
2417 paddr_nz (step_range_start),
2418 paddr_nz (step_range_end));
2423 /* We stepped out of the stepping range. */
2425 /* If we are stepping at the source level and entered the runtime
2426 loader dynamic symbol resolution code, we keep on single stepping
2427 until we exit the run time loader code and reach the callee's
2429 if (step_over_calls == STEP_OVER_UNDEBUGGABLE
2430 #ifdef IN_SOLIB_DYNSYM_RESOLVE_CODE
2431 && IN_SOLIB_DYNSYM_RESOLVE_CODE (stop_pc)
2433 && in_solib_dynsym_resolve_code (stop_pc)
2437 CORE_ADDR pc_after_resolver =
2438 gdbarch_skip_solib_resolver (current_gdbarch, stop_pc);
2441 fprintf_unfiltered (gdb_stdlog, "infrun: stepped into dynsym resolve code\n");
2443 if (pc_after_resolver)
2445 /* Set up a step-resume breakpoint at the address
2446 indicated by SKIP_SOLIB_RESOLVER. */
2447 struct symtab_and_line sr_sal;
2449 sr_sal.pc = pc_after_resolver;
2451 insert_step_resume_breakpoint_at_sal (sr_sal, null_frame_id);
2458 if (step_range_end != 1
2459 && (step_over_calls == STEP_OVER_UNDEBUGGABLE
2460 || step_over_calls == STEP_OVER_ALL)
2461 && get_frame_type (get_current_frame ()) == SIGTRAMP_FRAME)
2464 fprintf_unfiltered (gdb_stdlog, "infrun: stepped into signal trampoline\n");
2465 /* The inferior, while doing a "step" or "next", has ended up in
2466 a signal trampoline (either by a signal being delivered or by
2467 the signal handler returning). Just single-step until the
2468 inferior leaves the trampoline (either by calling the handler
2474 /* Check for subroutine calls. The check for the current frame
2475 equalling the step ID is not necessary - the check of the
2476 previous frame's ID is sufficient - but it is a common case and
2477 cheaper than checking the previous frame's ID.
2479 NOTE: frame_id_eq will never report two invalid frame IDs as
2480 being equal, so to get into this block, both the current and
2481 previous frame must have valid frame IDs. */
2482 if (!frame_id_eq (get_frame_id (get_current_frame ()), step_frame_id)
2483 && frame_id_eq (frame_unwind_id (get_current_frame ()), step_frame_id))
2485 CORE_ADDR real_stop_pc;
2488 fprintf_unfiltered (gdb_stdlog, "infrun: stepped into subroutine\n");
2490 if ((step_over_calls == STEP_OVER_NONE)
2491 || ((step_range_end == 1)
2492 && in_prologue (prev_pc, ecs->stop_func_start)))
2494 /* I presume that step_over_calls is only 0 when we're
2495 supposed to be stepping at the assembly language level
2496 ("stepi"). Just stop. */
2497 /* Also, maybe we just did a "nexti" inside a prolog, so we
2498 thought it was a subroutine call but it was not. Stop as
2501 print_stop_reason (END_STEPPING_RANGE, 0);
2502 stop_stepping (ecs);
2506 if (step_over_calls == STEP_OVER_ALL)
2508 /* We're doing a "next", set a breakpoint at callee's return
2509 address (the address at which the caller will
2511 insert_step_resume_breakpoint_at_caller (get_current_frame ());
2516 /* If we are in a function call trampoline (a stub between the
2517 calling routine and the real function), locate the real
2518 function. That's what tells us (a) whether we want to step
2519 into it at all, and (b) what prologue we want to run to the
2520 end of, if we do step into it. */
2521 real_stop_pc = skip_language_trampoline (get_current_frame (), stop_pc);
2522 if (real_stop_pc == 0)
2523 real_stop_pc = gdbarch_skip_trampoline_code
2524 (current_gdbarch, get_current_frame (), stop_pc);
2525 if (real_stop_pc != 0)
2526 ecs->stop_func_start = real_stop_pc;
2529 #ifdef IN_SOLIB_DYNSYM_RESOLVE_CODE
2530 IN_SOLIB_DYNSYM_RESOLVE_CODE (ecs->stop_func_start)
2532 in_solib_dynsym_resolve_code (ecs->stop_func_start)
2536 struct symtab_and_line sr_sal;
2538 sr_sal.pc = ecs->stop_func_start;
2540 insert_step_resume_breakpoint_at_sal (sr_sal, null_frame_id);
2545 /* If we have line number information for the function we are
2546 thinking of stepping into, step into it.
2548 If there are several symtabs at that PC (e.g. with include
2549 files), just want to know whether *any* of them have line
2550 numbers. find_pc_line handles this. */
2552 struct symtab_and_line tmp_sal;
2554 tmp_sal = find_pc_line (ecs->stop_func_start, 0);
2555 if (tmp_sal.line != 0)
2557 step_into_function (ecs);
2562 /* If we have no line number and the step-stop-if-no-debug is
2563 set, we stop the step so that the user has a chance to switch
2564 in assembly mode. */
2565 if (step_over_calls == STEP_OVER_UNDEBUGGABLE && step_stop_if_no_debug)
2568 print_stop_reason (END_STEPPING_RANGE, 0);
2569 stop_stepping (ecs);
2573 /* Set a breakpoint at callee's return address (the address at
2574 which the caller will resume). */
2575 insert_step_resume_breakpoint_at_caller (get_current_frame ());
2580 /* If we're in the return path from a shared library trampoline,
2581 we want to proceed through the trampoline when stepping. */
2582 if (gdbarch_in_solib_return_trampoline (current_gdbarch,
2583 stop_pc, ecs->stop_func_name))
2585 /* Determine where this trampoline returns. */
2586 CORE_ADDR real_stop_pc;
2587 real_stop_pc = gdbarch_skip_trampoline_code
2588 (current_gdbarch, get_current_frame (), stop_pc);
2591 fprintf_unfiltered (gdb_stdlog, "infrun: stepped into solib return tramp\n");
2593 /* Only proceed through if we know where it's going. */
2596 /* And put the step-breakpoint there and go until there. */
2597 struct symtab_and_line sr_sal;
2599 init_sal (&sr_sal); /* initialize to zeroes */
2600 sr_sal.pc = real_stop_pc;
2601 sr_sal.section = find_pc_overlay (sr_sal.pc);
2603 /* Do not specify what the fp should be when we stop since
2604 on some machines the prologue is where the new fp value
2606 insert_step_resume_breakpoint_at_sal (sr_sal, null_frame_id);
2608 /* Restart without fiddling with the step ranges or
2615 ecs->sal = find_pc_line (stop_pc, 0);
2617 /* NOTE: tausq/2004-05-24: This if block used to be done before all
2618 the trampoline processing logic, however, there are some trampolines
2619 that have no names, so we should do trampoline handling first. */
2620 if (step_over_calls == STEP_OVER_UNDEBUGGABLE
2621 && ecs->stop_func_name == NULL
2622 && ecs->sal.line == 0)
2625 fprintf_unfiltered (gdb_stdlog, "infrun: stepped into undebuggable function\n");
2627 /* The inferior just stepped into, or returned to, an
2628 undebuggable function (where there is no debugging information
2629 and no line number corresponding to the address where the
2630 inferior stopped). Since we want to skip this kind of code,
2631 we keep going until the inferior returns from this
2632 function - unless the user has asked us not to (via
2633 set step-mode) or we no longer know how to get back
2634 to the call site. */
2635 if (step_stop_if_no_debug
2636 || !frame_id_p (frame_unwind_id (get_current_frame ())))
2638 /* If we have no line number and the step-stop-if-no-debug
2639 is set, we stop the step so that the user has a chance to
2640 switch in assembly mode. */
2642 print_stop_reason (END_STEPPING_RANGE, 0);
2643 stop_stepping (ecs);
2648 /* Set a breakpoint at callee's return address (the address
2649 at which the caller will resume). */
2650 insert_step_resume_breakpoint_at_caller (get_current_frame ());
2656 if (step_range_end == 1)
2658 /* It is stepi or nexti. We always want to stop stepping after
2661 fprintf_unfiltered (gdb_stdlog, "infrun: stepi/nexti\n");
2663 print_stop_reason (END_STEPPING_RANGE, 0);
2664 stop_stepping (ecs);
2668 if (ecs->sal.line == 0)
2670 /* We have no line number information. That means to stop
2671 stepping (does this always happen right after one instruction,
2672 when we do "s" in a function with no line numbers,
2673 or can this happen as a result of a return or longjmp?). */
2675 fprintf_unfiltered (gdb_stdlog, "infrun: no line number info\n");
2677 print_stop_reason (END_STEPPING_RANGE, 0);
2678 stop_stepping (ecs);
2682 if ((stop_pc == ecs->sal.pc)
2683 && (ecs->current_line != ecs->sal.line
2684 || ecs->current_symtab != ecs->sal.symtab))
2686 /* We are at the start of a different line. So stop. Note that
2687 we don't stop if we step into the middle of a different line.
2688 That is said to make things like for (;;) statements work
2691 fprintf_unfiltered (gdb_stdlog, "infrun: stepped to a different line\n");
2693 print_stop_reason (END_STEPPING_RANGE, 0);
2694 stop_stepping (ecs);
2698 /* We aren't done stepping.
2700 Optimize by setting the stepping range to the line.
2701 (We might not be in the original line, but if we entered a
2702 new line in mid-statement, we continue stepping. This makes
2703 things like for(;;) statements work better.) */
2705 if (ecs->stop_func_end && ecs->sal.end >= ecs->stop_func_end)
2707 /* If this is the last line of the function, don't keep stepping
2708 (it would probably step us out of the function).
2709 This is particularly necessary for a one-line function,
2710 in which after skipping the prologue we better stop even though
2711 we will be in mid-line. */
2713 fprintf_unfiltered (gdb_stdlog, "infrun: stepped to a different function\n");
2715 print_stop_reason (END_STEPPING_RANGE, 0);
2716 stop_stepping (ecs);
2719 step_range_start = ecs->sal.pc;
2720 step_range_end = ecs->sal.end;
2721 step_frame_id = get_frame_id (get_current_frame ());
2722 ecs->current_line = ecs->sal.line;
2723 ecs->current_symtab = ecs->sal.symtab;
2725 /* In the case where we just stepped out of a function into the
2726 middle of a line of the caller, continue stepping, but
2727 step_frame_id must be modified to current frame */
2729 /* NOTE: cagney/2003-10-16: I think this frame ID inner test is too
2730 generous. It will trigger on things like a step into a frameless
2731 stackless leaf function. I think the logic should instead look
2732 at the unwound frame ID has that should give a more robust
2733 indication of what happened. */
2734 if (step - ID == current - ID)
2735 still stepping in same function;
2736 else if (step - ID == unwind (current - ID))
2737 stepped into a function;
2739 stepped out of a function;
2740 /* Of course this assumes that the frame ID unwind code is robust
2741 and we're willing to introduce frame unwind logic into this
2742 function. Fortunately, those days are nearly upon us. */
2745 struct frame_info *frame = get_current_frame ();
2746 struct frame_id current_frame = get_frame_id (frame);
2747 if (!(frame_id_inner (get_frame_arch (frame), current_frame,
2749 step_frame_id = current_frame;
2753 fprintf_unfiltered (gdb_stdlog, "infrun: keep going\n");
2757 /* Are we in the middle of stepping? */
2760 currently_stepping (struct execution_control_state *ecs)
2762 return ((!ecs->handling_longjmp
2763 && ((step_range_end && step_resume_breakpoint == NULL)
2764 || stepping_over_breakpoint))
2765 || ecs->stepping_through_solib_after_catch
2766 || bpstat_should_step ());
2769 /* Subroutine call with source code we should not step over. Do step
2770 to the first line of code in it. */
2773 step_into_function (struct execution_control_state *ecs)
2776 struct symtab_and_line sr_sal;
2778 s = find_pc_symtab (stop_pc);
2779 if (s && s->language != language_asm)
2780 ecs->stop_func_start = gdbarch_skip_prologue
2781 (current_gdbarch, ecs->stop_func_start);
2783 ecs->sal = find_pc_line (ecs->stop_func_start, 0);
2784 /* Use the step_resume_break to step until the end of the prologue,
2785 even if that involves jumps (as it seems to on the vax under
2787 /* If the prologue ends in the middle of a source line, continue to
2788 the end of that source line (if it is still within the function).
2789 Otherwise, just go to end of prologue. */
2791 && ecs->sal.pc != ecs->stop_func_start
2792 && ecs->sal.end < ecs->stop_func_end)
2793 ecs->stop_func_start = ecs->sal.end;
2795 /* Architectures which require breakpoint adjustment might not be able
2796 to place a breakpoint at the computed address. If so, the test
2797 ``ecs->stop_func_start == stop_pc'' will never succeed. Adjust
2798 ecs->stop_func_start to an address at which a breakpoint may be
2799 legitimately placed.
2801 Note: kevinb/2004-01-19: On FR-V, if this adjustment is not
2802 made, GDB will enter an infinite loop when stepping through
2803 optimized code consisting of VLIW instructions which contain
2804 subinstructions corresponding to different source lines. On
2805 FR-V, it's not permitted to place a breakpoint on any but the
2806 first subinstruction of a VLIW instruction. When a breakpoint is
2807 set, GDB will adjust the breakpoint address to the beginning of
2808 the VLIW instruction. Thus, we need to make the corresponding
2809 adjustment here when computing the stop address. */
2811 if (gdbarch_adjust_breakpoint_address_p (current_gdbarch))
2813 ecs->stop_func_start
2814 = gdbarch_adjust_breakpoint_address (current_gdbarch,
2815 ecs->stop_func_start);
2818 if (ecs->stop_func_start == stop_pc)
2820 /* We are already there: stop now. */
2822 print_stop_reason (END_STEPPING_RANGE, 0);
2823 stop_stepping (ecs);
2828 /* Put the step-breakpoint there and go until there. */
2829 init_sal (&sr_sal); /* initialize to zeroes */
2830 sr_sal.pc = ecs->stop_func_start;
2831 sr_sal.section = find_pc_overlay (ecs->stop_func_start);
2833 /* Do not specify what the fp should be when we stop since on
2834 some machines the prologue is where the new fp value is
2836 insert_step_resume_breakpoint_at_sal (sr_sal, null_frame_id);
2838 /* And make sure stepping stops right away then. */
2839 step_range_end = step_range_start;
2844 /* Insert a "step-resume breakpoint" at SR_SAL with frame ID SR_ID.
2845 This is used to both functions and to skip over code. */
2848 insert_step_resume_breakpoint_at_sal (struct symtab_and_line sr_sal,
2849 struct frame_id sr_id)
2851 /* There should never be more than one step-resume breakpoint per
2852 thread, so we should never be setting a new
2853 step_resume_breakpoint when one is already active. */
2854 gdb_assert (step_resume_breakpoint == NULL);
2857 fprintf_unfiltered (gdb_stdlog,
2858 "infrun: inserting step-resume breakpoint at 0x%s\n",
2859 paddr_nz (sr_sal.pc));
2861 step_resume_breakpoint = set_momentary_breakpoint (sr_sal, sr_id,
2865 /* Insert a "step-resume breakpoint" at RETURN_FRAME.pc. This is used
2866 to skip a potential signal handler.
2868 This is called with the interrupted function's frame. The signal
2869 handler, when it returns, will resume the interrupted function at
2873 insert_step_resume_breakpoint_at_frame (struct frame_info *return_frame)
2875 struct symtab_and_line sr_sal;
2877 gdb_assert (return_frame != NULL);
2878 init_sal (&sr_sal); /* initialize to zeros */
2880 sr_sal.pc = gdbarch_addr_bits_remove
2881 (current_gdbarch, get_frame_pc (return_frame));
2882 sr_sal.section = find_pc_overlay (sr_sal.pc);
2884 insert_step_resume_breakpoint_at_sal (sr_sal, get_frame_id (return_frame));
2887 /* Similar to insert_step_resume_breakpoint_at_frame, except
2888 but a breakpoint at the previous frame's PC. This is used to
2889 skip a function after stepping into it (for "next" or if the called
2890 function has no debugging information).
2892 The current function has almost always been reached by single
2893 stepping a call or return instruction. NEXT_FRAME belongs to the
2894 current function, and the breakpoint will be set at the caller's
2897 This is a separate function rather than reusing
2898 insert_step_resume_breakpoint_at_frame in order to avoid
2899 get_prev_frame, which may stop prematurely (see the implementation
2900 of frame_unwind_id for an example). */
2903 insert_step_resume_breakpoint_at_caller (struct frame_info *next_frame)
2905 struct symtab_and_line sr_sal;
2907 /* We shouldn't have gotten here if we don't know where the call site
2909 gdb_assert (frame_id_p (frame_unwind_id (next_frame)));
2911 init_sal (&sr_sal); /* initialize to zeros */
2913 sr_sal.pc = gdbarch_addr_bits_remove
2914 (current_gdbarch, frame_pc_unwind (next_frame));
2915 sr_sal.section = find_pc_overlay (sr_sal.pc);
2917 insert_step_resume_breakpoint_at_sal (sr_sal, frame_unwind_id (next_frame));
2921 stop_stepping (struct execution_control_state *ecs)
2924 fprintf_unfiltered (gdb_stdlog, "infrun: stop_stepping\n");
2926 /* Let callers know we don't want to wait for the inferior anymore. */
2927 ecs->wait_some_more = 0;
2930 /* This function handles various cases where we need to continue
2931 waiting for the inferior. */
2932 /* (Used to be the keep_going: label in the old wait_for_inferior) */
2935 keep_going (struct execution_control_state *ecs)
2937 /* Save the pc before execution, to compare with pc after stop. */
2938 prev_pc = read_pc (); /* Might have been DECR_AFTER_BREAK */
2940 /* If we did not do break;, it means we should keep running the
2941 inferior and not return to debugger. */
2943 if (stepping_over_breakpoint && stop_signal != TARGET_SIGNAL_TRAP)
2945 /* We took a signal (which we are supposed to pass through to
2946 the inferior, else we'd have done a break above) and we
2947 haven't yet gotten our trap. Simply continue. */
2948 resume (currently_stepping (ecs), stop_signal);
2952 /* Either the trap was not expected, but we are continuing
2953 anyway (the user asked that this signal be passed to the
2956 The signal was SIGTRAP, e.g. it was our signal, but we
2957 decided we should resume from it.
2959 We're going to run this baby now!
2961 Note that insert_breakpoints won't try to re-insert
2962 already inserted breakpoints. Therefore, we don't
2963 care if breakpoints were already inserted, or not. */
2965 if (!ecs->stepping_over_breakpoint)
2967 struct gdb_exception e;
2968 /* Stop stepping when inserting breakpoints
2970 TRY_CATCH (e, RETURN_MASK_ERROR)
2972 insert_breakpoints ();
2976 stop_stepping (ecs);
2981 stepping_over_breakpoint = ecs->stepping_over_breakpoint;
2983 /* Do not deliver SIGNAL_TRAP (except when the user explicitly
2984 specifies that such a signal should be delivered to the
2987 Typically, this would occure when a user is debugging a
2988 target monitor on a simulator: the target monitor sets a
2989 breakpoint; the simulator encounters this break-point and
2990 halts the simulation handing control to GDB; GDB, noteing
2991 that the break-point isn't valid, returns control back to the
2992 simulator; the simulator then delivers the hardware
2993 equivalent of a SIGNAL_TRAP to the program being debugged. */
2995 if (stop_signal == TARGET_SIGNAL_TRAP && !signal_program[stop_signal])
2996 stop_signal = TARGET_SIGNAL_0;
2999 resume (currently_stepping (ecs), stop_signal);
3002 prepare_to_wait (ecs);
3005 /* This function normally comes after a resume, before
3006 handle_inferior_event exits. It takes care of any last bits of
3007 housekeeping, and sets the all-important wait_some_more flag. */
3010 prepare_to_wait (struct execution_control_state *ecs)
3013 fprintf_unfiltered (gdb_stdlog, "infrun: prepare_to_wait\n");
3014 if (ecs->infwait_state == infwait_normal_state)
3016 overlay_cache_invalid = 1;
3018 /* We have to invalidate the registers BEFORE calling
3019 target_wait because they can be loaded from the target while
3020 in target_wait. This makes remote debugging a bit more
3021 efficient for those targets that provide critical registers
3022 as part of their normal status mechanism. */
3024 registers_changed ();
3025 ecs->waiton_ptid = pid_to_ptid (-1);
3026 ecs->wp = &(ecs->ws);
3028 /* This is the old end of the while loop. Let everybody know we
3029 want to wait for the inferior some more and get called again
3031 ecs->wait_some_more = 1;
3034 /* Print why the inferior has stopped. We always print something when
3035 the inferior exits, or receives a signal. The rest of the cases are
3036 dealt with later on in normal_stop() and print_it_typical(). Ideally
3037 there should be a call to this function from handle_inferior_event()
3038 each time stop_stepping() is called.*/
3040 print_stop_reason (enum inferior_stop_reason stop_reason, int stop_info)
3042 switch (stop_reason)
3044 case END_STEPPING_RANGE:
3045 /* We are done with a step/next/si/ni command. */
3046 /* For now print nothing. */
3047 /* Print a message only if not in the middle of doing a "step n"
3048 operation for n > 1 */
3049 if (!step_multi || !stop_step)
3050 if (ui_out_is_mi_like_p (uiout))
3053 async_reason_lookup (EXEC_ASYNC_END_STEPPING_RANGE));
3056 /* The inferior was terminated by a signal. */
3057 annotate_signalled ();
3058 if (ui_out_is_mi_like_p (uiout))
3061 async_reason_lookup (EXEC_ASYNC_EXITED_SIGNALLED));
3062 ui_out_text (uiout, "\nProgram terminated with signal ");
3063 annotate_signal_name ();
3064 ui_out_field_string (uiout, "signal-name",
3065 target_signal_to_name (stop_info));
3066 annotate_signal_name_end ();
3067 ui_out_text (uiout, ", ");
3068 annotate_signal_string ();
3069 ui_out_field_string (uiout, "signal-meaning",
3070 target_signal_to_string (stop_info));
3071 annotate_signal_string_end ();
3072 ui_out_text (uiout, ".\n");
3073 ui_out_text (uiout, "The program no longer exists.\n");
3076 /* The inferior program is finished. */
3077 annotate_exited (stop_info);
3080 if (ui_out_is_mi_like_p (uiout))
3081 ui_out_field_string (uiout, "reason",
3082 async_reason_lookup (EXEC_ASYNC_EXITED));
3083 ui_out_text (uiout, "\nProgram exited with code ");
3084 ui_out_field_fmt (uiout, "exit-code", "0%o",
3085 (unsigned int) stop_info);
3086 ui_out_text (uiout, ".\n");
3090 if (ui_out_is_mi_like_p (uiout))
3093 async_reason_lookup (EXEC_ASYNC_EXITED_NORMALLY));
3094 ui_out_text (uiout, "\nProgram exited normally.\n");
3096 /* Support the --return-child-result option. */
3097 return_child_result_value = stop_info;
3099 case SIGNAL_RECEIVED:
3100 /* Signal received. The signal table tells us to print about
3103 ui_out_text (uiout, "\nProgram received signal ");
3104 annotate_signal_name ();
3105 if (ui_out_is_mi_like_p (uiout))
3107 (uiout, "reason", async_reason_lookup (EXEC_ASYNC_SIGNAL_RECEIVED));
3108 ui_out_field_string (uiout, "signal-name",
3109 target_signal_to_name (stop_info));
3110 annotate_signal_name_end ();
3111 ui_out_text (uiout, ", ");
3112 annotate_signal_string ();
3113 ui_out_field_string (uiout, "signal-meaning",
3114 target_signal_to_string (stop_info));
3115 annotate_signal_string_end ();
3116 ui_out_text (uiout, ".\n");
3119 internal_error (__FILE__, __LINE__,
3120 _("print_stop_reason: unrecognized enum value"));
3126 /* Here to return control to GDB when the inferior stops for real.
3127 Print appropriate messages, remove breakpoints, give terminal our modes.
3129 STOP_PRINT_FRAME nonzero means print the executing frame
3130 (pc, function, args, file, line number and line text).
3131 BREAKPOINTS_FAILED nonzero means stop was due to error
3132 attempting to insert breakpoints. */
3137 struct target_waitstatus last;
3140 get_last_target_status (&last_ptid, &last);
3142 /* As with the notification of thread events, we want to delay
3143 notifying the user that we've switched thread context until
3144 the inferior actually stops.
3146 There's no point in saying anything if the inferior has exited.
3147 Note that SIGNALLED here means "exited with a signal", not
3148 "received a signal". */
3149 if (!ptid_equal (previous_inferior_ptid, inferior_ptid)
3150 && target_has_execution
3151 && last.kind != TARGET_WAITKIND_SIGNALLED
3152 && last.kind != TARGET_WAITKIND_EXITED)
3154 target_terminal_ours_for_output ();
3155 printf_filtered (_("[Switching to %s]\n"),
3156 target_pid_or_tid_to_str (inferior_ptid));
3157 previous_inferior_ptid = inferior_ptid;
3160 /* NOTE drow/2004-01-17: Is this still necessary? */
3161 /* Make sure that the current_frame's pc is correct. This
3162 is a correction for setting up the frame info before doing
3163 gdbarch_decr_pc_after_break */
3164 if (target_has_execution)
3165 /* FIXME: cagney/2002-12-06: Has the PC changed? Thanks to
3166 gdbarch_decr_pc_after_break, the program counter can change. Ask the
3167 frame code to check for this and sort out any resultant mess.
3168 gdbarch_decr_pc_after_break needs to just go away. */
3169 deprecated_update_frame_pc_hack (get_current_frame (), read_pc ());
3171 if (target_has_execution)
3173 if (remove_breakpoints ())
3175 target_terminal_ours_for_output ();
3176 printf_filtered (_("\
3177 Cannot remove breakpoints because program is no longer writable.\n\
3178 It might be running in another process.\n\
3179 Further execution is probably impossible.\n"));
3183 /* Delete the breakpoint we stopped at, if it wants to be deleted.
3184 Delete any breakpoint that is to be deleted at the next stop. */
3186 breakpoint_auto_delete (stop_bpstat);
3188 /* If an auto-display called a function and that got a signal,
3189 delete that auto-display to avoid an infinite recursion. */
3191 if (stopped_by_random_signal)
3192 disable_current_display ();
3194 /* Don't print a message if in the middle of doing a "step n"
3195 operation for n > 1 */
3196 if (step_multi && stop_step)
3199 target_terminal_ours ();
3201 /* Set the current source location. This will also happen if we
3202 display the frame below, but the current SAL will be incorrect
3203 during a user hook-stop function. */
3204 if (target_has_stack && !stop_stack_dummy)
3205 set_current_sal_from_frame (get_current_frame (), 1);
3207 /* Look up the hook_stop and run it (CLI internally handles problem
3208 of stop_command's pre-hook not existing). */
3210 catch_errors (hook_stop_stub, stop_command,
3211 "Error while running hook_stop:\n", RETURN_MASK_ALL);
3213 if (!target_has_stack)
3219 /* Select innermost stack frame - i.e., current frame is frame 0,
3220 and current location is based on that.
3221 Don't do this on return from a stack dummy routine,
3222 or if the program has exited. */
3224 if (!stop_stack_dummy)
3226 select_frame (get_current_frame ());
3228 /* Print current location without a level number, if
3229 we have changed functions or hit a breakpoint.
3230 Print source line if we have one.
3231 bpstat_print() contains the logic deciding in detail
3232 what to print, based on the event(s) that just occurred. */
3234 if (stop_print_frame)
3238 int do_frame_printing = 1;
3240 bpstat_ret = bpstat_print (stop_bpstat);
3244 /* If we had hit a shared library event breakpoint,
3245 bpstat_print would print out this message. If we hit
3246 an OS-level shared library event, do the same
3248 if (last.kind == TARGET_WAITKIND_LOADED)
3250 printf_filtered (_("Stopped due to shared library event\n"));
3251 source_flag = SRC_LINE; /* something bogus */
3252 do_frame_printing = 0;
3256 /* FIXME: cagney/2002-12-01: Given that a frame ID does
3257 (or should) carry around the function and does (or
3258 should) use that when doing a frame comparison. */
3260 && frame_id_eq (step_frame_id,
3261 get_frame_id (get_current_frame ()))
3262 && step_start_function == find_pc_function (stop_pc))
3263 source_flag = SRC_LINE; /* finished step, just print source line */
3265 source_flag = SRC_AND_LOC; /* print location and source line */
3267 case PRINT_SRC_AND_LOC:
3268 source_flag = SRC_AND_LOC; /* print location and source line */
3270 case PRINT_SRC_ONLY:
3271 source_flag = SRC_LINE;
3274 source_flag = SRC_LINE; /* something bogus */
3275 do_frame_printing = 0;
3278 internal_error (__FILE__, __LINE__, _("Unknown value."));
3281 if (ui_out_is_mi_like_p (uiout))
3282 ui_out_field_int (uiout, "thread-id",
3283 pid_to_thread_id (inferior_ptid));
3284 /* The behavior of this routine with respect to the source
3286 SRC_LINE: Print only source line
3287 LOCATION: Print only location
3288 SRC_AND_LOC: Print location and source line */
3289 if (do_frame_printing)
3290 print_stack_frame (get_selected_frame (NULL), 0, source_flag);
3292 /* Display the auto-display expressions. */
3297 /* Save the function value return registers, if we care.
3298 We might be about to restore their previous contents. */
3299 if (proceed_to_finish)
3301 /* This should not be necessary. */
3303 regcache_xfree (stop_registers);
3305 /* NB: The copy goes through to the target picking up the value of
3306 all the registers. */
3307 stop_registers = regcache_dup (get_current_regcache ());
3310 if (stop_stack_dummy)
3312 /* Pop the empty frame that contains the stack dummy. POP_FRAME
3313 ends with a setting of the current frame, so we can use that
3315 frame_pop (get_current_frame ());
3316 /* Set stop_pc to what it was before we called the function.
3317 Can't rely on restore_inferior_status because that only gets
3318 called if we don't stop in the called function. */
3319 stop_pc = read_pc ();
3320 select_frame (get_current_frame ());
3324 annotate_stopped ();
3325 observer_notify_normal_stop (stop_bpstat);
3329 hook_stop_stub (void *cmd)
3331 execute_cmd_pre_hook ((struct cmd_list_element *) cmd);
3336 signal_stop_state (int signo)
3338 return signal_stop[signo];
3342 signal_print_state (int signo)
3344 return signal_print[signo];
3348 signal_pass_state (int signo)
3350 return signal_program[signo];
3354 signal_stop_update (int signo, int state)
3356 int ret = signal_stop[signo];
3357 signal_stop[signo] = state;
3362 signal_print_update (int signo, int state)
3364 int ret = signal_print[signo];
3365 signal_print[signo] = state;
3370 signal_pass_update (int signo, int state)
3372 int ret = signal_program[signo];
3373 signal_program[signo] = state;
3378 sig_print_header (void)
3380 printf_filtered (_("\
3381 Signal Stop\tPrint\tPass to program\tDescription\n"));
3385 sig_print_info (enum target_signal oursig)
3387 char *name = target_signal_to_name (oursig);
3388 int name_padding = 13 - strlen (name);
3390 if (name_padding <= 0)
3393 printf_filtered ("%s", name);
3394 printf_filtered ("%*.*s ", name_padding, name_padding, " ");
3395 printf_filtered ("%s\t", signal_stop[oursig] ? "Yes" : "No");
3396 printf_filtered ("%s\t", signal_print[oursig] ? "Yes" : "No");
3397 printf_filtered ("%s\t\t", signal_program[oursig] ? "Yes" : "No");
3398 printf_filtered ("%s\n", target_signal_to_string (oursig));
3401 /* Specify how various signals in the inferior should be handled. */
3404 handle_command (char *args, int from_tty)
3407 int digits, wordlen;
3408 int sigfirst, signum, siglast;
3409 enum target_signal oursig;
3412 unsigned char *sigs;
3413 struct cleanup *old_chain;
3417 error_no_arg (_("signal to handle"));
3420 /* Allocate and zero an array of flags for which signals to handle. */
3422 nsigs = (int) TARGET_SIGNAL_LAST;
3423 sigs = (unsigned char *) alloca (nsigs);
3424 memset (sigs, 0, nsigs);
3426 /* Break the command line up into args. */
3428 argv = buildargv (args);
3433 old_chain = make_cleanup_freeargv (argv);
3435 /* Walk through the args, looking for signal oursigs, signal names, and
3436 actions. Signal numbers and signal names may be interspersed with
3437 actions, with the actions being performed for all signals cumulatively
3438 specified. Signal ranges can be specified as <LOW>-<HIGH>. */
3440 while (*argv != NULL)
3442 wordlen = strlen (*argv);
3443 for (digits = 0; isdigit ((*argv)[digits]); digits++)
3447 sigfirst = siglast = -1;
3449 if (wordlen >= 1 && !strncmp (*argv, "all", wordlen))
3451 /* Apply action to all signals except those used by the
3452 debugger. Silently skip those. */
3455 siglast = nsigs - 1;
3457 else if (wordlen >= 1 && !strncmp (*argv, "stop", wordlen))
3459 SET_SIGS (nsigs, sigs, signal_stop);
3460 SET_SIGS (nsigs, sigs, signal_print);
3462 else if (wordlen >= 1 && !strncmp (*argv, "ignore", wordlen))
3464 UNSET_SIGS (nsigs, sigs, signal_program);
3466 else if (wordlen >= 2 && !strncmp (*argv, "print", wordlen))
3468 SET_SIGS (nsigs, sigs, signal_print);
3470 else if (wordlen >= 2 && !strncmp (*argv, "pass", wordlen))
3472 SET_SIGS (nsigs, sigs, signal_program);
3474 else if (wordlen >= 3 && !strncmp (*argv, "nostop", wordlen))
3476 UNSET_SIGS (nsigs, sigs, signal_stop);
3478 else if (wordlen >= 3 && !strncmp (*argv, "noignore", wordlen))
3480 SET_SIGS (nsigs, sigs, signal_program);
3482 else if (wordlen >= 4 && !strncmp (*argv, "noprint", wordlen))
3484 UNSET_SIGS (nsigs, sigs, signal_print);
3485 UNSET_SIGS (nsigs, sigs, signal_stop);
3487 else if (wordlen >= 4 && !strncmp (*argv, "nopass", wordlen))
3489 UNSET_SIGS (nsigs, sigs, signal_program);
3491 else if (digits > 0)
3493 /* It is numeric. The numeric signal refers to our own
3494 internal signal numbering from target.h, not to host/target
3495 signal number. This is a feature; users really should be
3496 using symbolic names anyway, and the common ones like
3497 SIGHUP, SIGINT, SIGALRM, etc. will work right anyway. */
3499 sigfirst = siglast = (int)
3500 target_signal_from_command (atoi (*argv));
3501 if ((*argv)[digits] == '-')
3504 target_signal_from_command (atoi ((*argv) + digits + 1));
3506 if (sigfirst > siglast)
3508 /* Bet he didn't figure we'd think of this case... */
3516 oursig = target_signal_from_name (*argv);
3517 if (oursig != TARGET_SIGNAL_UNKNOWN)
3519 sigfirst = siglast = (int) oursig;
3523 /* Not a number and not a recognized flag word => complain. */
3524 error (_("Unrecognized or ambiguous flag word: \"%s\"."), *argv);
3528 /* If any signal numbers or symbol names were found, set flags for
3529 which signals to apply actions to. */
3531 for (signum = sigfirst; signum >= 0 && signum <= siglast; signum++)
3533 switch ((enum target_signal) signum)
3535 case TARGET_SIGNAL_TRAP:
3536 case TARGET_SIGNAL_INT:
3537 if (!allsigs && !sigs[signum])
3539 if (query ("%s is used by the debugger.\n\
3540 Are you sure you want to change it? ", target_signal_to_name ((enum target_signal) signum)))
3546 printf_unfiltered (_("Not confirmed, unchanged.\n"));
3547 gdb_flush (gdb_stdout);
3551 case TARGET_SIGNAL_0:
3552 case TARGET_SIGNAL_DEFAULT:
3553 case TARGET_SIGNAL_UNKNOWN:
3554 /* Make sure that "all" doesn't print these. */
3565 target_notice_signals (inferior_ptid);
3569 /* Show the results. */
3570 sig_print_header ();
3571 for (signum = 0; signum < nsigs; signum++)
3575 sig_print_info (signum);
3580 do_cleanups (old_chain);
3584 xdb_handle_command (char *args, int from_tty)
3587 struct cleanup *old_chain;
3589 /* Break the command line up into args. */
3591 argv = buildargv (args);
3596 old_chain = make_cleanup_freeargv (argv);
3597 if (argv[1] != (char *) NULL)
3602 bufLen = strlen (argv[0]) + 20;
3603 argBuf = (char *) xmalloc (bufLen);
3607 enum target_signal oursig;
3609 oursig = target_signal_from_name (argv[0]);
3610 memset (argBuf, 0, bufLen);
3611 if (strcmp (argv[1], "Q") == 0)
3612 sprintf (argBuf, "%s %s", argv[0], "noprint");
3615 if (strcmp (argv[1], "s") == 0)
3617 if (!signal_stop[oursig])
3618 sprintf (argBuf, "%s %s", argv[0], "stop");
3620 sprintf (argBuf, "%s %s", argv[0], "nostop");
3622 else if (strcmp (argv[1], "i") == 0)
3624 if (!signal_program[oursig])
3625 sprintf (argBuf, "%s %s", argv[0], "pass");
3627 sprintf (argBuf, "%s %s", argv[0], "nopass");
3629 else if (strcmp (argv[1], "r") == 0)
3631 if (!signal_print[oursig])
3632 sprintf (argBuf, "%s %s", argv[0], "print");
3634 sprintf (argBuf, "%s %s", argv[0], "noprint");
3640 handle_command (argBuf, from_tty);
3642 printf_filtered (_("Invalid signal handling flag.\n"));
3647 do_cleanups (old_chain);
3650 /* Print current contents of the tables set by the handle command.
3651 It is possible we should just be printing signals actually used
3652 by the current target (but for things to work right when switching
3653 targets, all signals should be in the signal tables). */
3656 signals_info (char *signum_exp, int from_tty)
3658 enum target_signal oursig;
3659 sig_print_header ();
3663 /* First see if this is a symbol name. */
3664 oursig = target_signal_from_name (signum_exp);
3665 if (oursig == TARGET_SIGNAL_UNKNOWN)
3667 /* No, try numeric. */
3669 target_signal_from_command (parse_and_eval_long (signum_exp));
3671 sig_print_info (oursig);
3675 printf_filtered ("\n");
3676 /* These ugly casts brought to you by the native VAX compiler. */
3677 for (oursig = TARGET_SIGNAL_FIRST;
3678 (int) oursig < (int) TARGET_SIGNAL_LAST;
3679 oursig = (enum target_signal) ((int) oursig + 1))
3683 if (oursig != TARGET_SIGNAL_UNKNOWN
3684 && oursig != TARGET_SIGNAL_DEFAULT && oursig != TARGET_SIGNAL_0)
3685 sig_print_info (oursig);
3688 printf_filtered (_("\nUse the \"handle\" command to change these tables.\n"));
3691 struct inferior_status
3693 enum target_signal stop_signal;
3697 int stop_stack_dummy;
3698 int stopped_by_random_signal;
3699 int stepping_over_breakpoint;
3700 CORE_ADDR step_range_start;
3701 CORE_ADDR step_range_end;
3702 struct frame_id step_frame_id;
3703 enum step_over_calls_kind step_over_calls;
3704 CORE_ADDR step_resume_break_address;
3705 int stop_after_trap;
3708 /* These are here because if call_function_by_hand has written some
3709 registers and then decides to call error(), we better not have changed
3711 struct regcache *registers;
3713 /* A frame unique identifier. */
3714 struct frame_id selected_frame_id;
3716 int breakpoint_proceeded;
3717 int restore_stack_info;
3718 int proceed_to_finish;
3722 write_inferior_status_register (struct inferior_status *inf_status, int regno,
3725 int size = register_size (current_gdbarch, regno);
3726 void *buf = alloca (size);
3727 store_signed_integer (buf, size, val);
3728 regcache_raw_write (inf_status->registers, regno, buf);
3731 /* Save all of the information associated with the inferior<==>gdb
3732 connection. INF_STATUS is a pointer to a "struct inferior_status"
3733 (defined in inferior.h). */
3735 struct inferior_status *
3736 save_inferior_status (int restore_stack_info)
3738 struct inferior_status *inf_status = XMALLOC (struct inferior_status);
3740 inf_status->stop_signal = stop_signal;
3741 inf_status->stop_pc = stop_pc;
3742 inf_status->stop_step = stop_step;
3743 inf_status->stop_stack_dummy = stop_stack_dummy;
3744 inf_status->stopped_by_random_signal = stopped_by_random_signal;
3745 inf_status->stepping_over_breakpoint = stepping_over_breakpoint;
3746 inf_status->step_range_start = step_range_start;
3747 inf_status->step_range_end = step_range_end;
3748 inf_status->step_frame_id = step_frame_id;
3749 inf_status->step_over_calls = step_over_calls;
3750 inf_status->stop_after_trap = stop_after_trap;
3751 inf_status->stop_soon = stop_soon;
3752 /* Save original bpstat chain here; replace it with copy of chain.
3753 If caller's caller is walking the chain, they'll be happier if we
3754 hand them back the original chain when restore_inferior_status is
3756 inf_status->stop_bpstat = stop_bpstat;
3757 stop_bpstat = bpstat_copy (stop_bpstat);
3758 inf_status->breakpoint_proceeded = breakpoint_proceeded;
3759 inf_status->restore_stack_info = restore_stack_info;
3760 inf_status->proceed_to_finish = proceed_to_finish;
3762 inf_status->registers = regcache_dup (get_current_regcache ());
3764 inf_status->selected_frame_id = get_frame_id (get_selected_frame (NULL));
3769 restore_selected_frame (void *args)
3771 struct frame_id *fid = (struct frame_id *) args;
3772 struct frame_info *frame;
3774 frame = frame_find_by_id (*fid);
3776 /* If inf_status->selected_frame_id is NULL, there was no previously
3780 warning (_("Unable to restore previously selected frame."));
3784 select_frame (frame);
3790 restore_inferior_status (struct inferior_status *inf_status)
3792 stop_signal = inf_status->stop_signal;
3793 stop_pc = inf_status->stop_pc;
3794 stop_step = inf_status->stop_step;
3795 stop_stack_dummy = inf_status->stop_stack_dummy;
3796 stopped_by_random_signal = inf_status->stopped_by_random_signal;
3797 stepping_over_breakpoint = inf_status->stepping_over_breakpoint;
3798 step_range_start = inf_status->step_range_start;
3799 step_range_end = inf_status->step_range_end;
3800 step_frame_id = inf_status->step_frame_id;
3801 step_over_calls = inf_status->step_over_calls;
3802 stop_after_trap = inf_status->stop_after_trap;
3803 stop_soon = inf_status->stop_soon;
3804 bpstat_clear (&stop_bpstat);
3805 stop_bpstat = inf_status->stop_bpstat;
3806 breakpoint_proceeded = inf_status->breakpoint_proceeded;
3807 proceed_to_finish = inf_status->proceed_to_finish;
3809 /* The inferior can be gone if the user types "print exit(0)"
3810 (and perhaps other times). */
3811 if (target_has_execution)
3812 /* NB: The register write goes through to the target. */
3813 regcache_cpy (get_current_regcache (), inf_status->registers);
3814 regcache_xfree (inf_status->registers);
3816 /* FIXME: If we are being called after stopping in a function which
3817 is called from gdb, we should not be trying to restore the
3818 selected frame; it just prints a spurious error message (The
3819 message is useful, however, in detecting bugs in gdb (like if gdb
3820 clobbers the stack)). In fact, should we be restoring the
3821 inferior status at all in that case? . */
3823 if (target_has_stack && inf_status->restore_stack_info)
3825 /* The point of catch_errors is that if the stack is clobbered,
3826 walking the stack might encounter a garbage pointer and
3827 error() trying to dereference it. */
3829 (restore_selected_frame, &inf_status->selected_frame_id,
3830 "Unable to restore previously selected frame:\n",
3831 RETURN_MASK_ERROR) == 0)
3832 /* Error in restoring the selected frame. Select the innermost
3834 select_frame (get_current_frame ());
3842 do_restore_inferior_status_cleanup (void *sts)
3844 restore_inferior_status (sts);
3848 make_cleanup_restore_inferior_status (struct inferior_status *inf_status)
3850 return make_cleanup (do_restore_inferior_status_cleanup, inf_status);
3854 discard_inferior_status (struct inferior_status *inf_status)
3856 /* See save_inferior_status for info on stop_bpstat. */
3857 bpstat_clear (&inf_status->stop_bpstat);
3858 regcache_xfree (inf_status->registers);
3863 inferior_has_forked (int pid, int *child_pid)
3865 struct target_waitstatus last;
3868 get_last_target_status (&last_ptid, &last);
3870 if (last.kind != TARGET_WAITKIND_FORKED)
3873 if (ptid_get_pid (last_ptid) != pid)
3876 *child_pid = last.value.related_pid;
3881 inferior_has_vforked (int pid, int *child_pid)
3883 struct target_waitstatus last;
3886 get_last_target_status (&last_ptid, &last);
3888 if (last.kind != TARGET_WAITKIND_VFORKED)
3891 if (ptid_get_pid (last_ptid) != pid)
3894 *child_pid = last.value.related_pid;
3899 inferior_has_execd (int pid, char **execd_pathname)
3901 struct target_waitstatus last;
3904 get_last_target_status (&last_ptid, &last);
3906 if (last.kind != TARGET_WAITKIND_EXECD)
3909 if (ptid_get_pid (last_ptid) != pid)
3912 *execd_pathname = xstrdup (last.value.execd_pathname);
3916 /* Oft used ptids */
3918 ptid_t minus_one_ptid;
3920 /* Create a ptid given the necessary PID, LWP, and TID components. */
3923 ptid_build (int pid, long lwp, long tid)
3933 /* Create a ptid from just a pid. */
3936 pid_to_ptid (int pid)
3938 return ptid_build (pid, 0, 0);
3941 /* Fetch the pid (process id) component from a ptid. */
3944 ptid_get_pid (ptid_t ptid)
3949 /* Fetch the lwp (lightweight process) component from a ptid. */
3952 ptid_get_lwp (ptid_t ptid)
3957 /* Fetch the tid (thread id) component from a ptid. */
3960 ptid_get_tid (ptid_t ptid)
3965 /* ptid_equal() is used to test equality of two ptids. */
3968 ptid_equal (ptid_t ptid1, ptid_t ptid2)
3970 return (ptid1.pid == ptid2.pid && ptid1.lwp == ptid2.lwp
3971 && ptid1.tid == ptid2.tid);
3974 /* restore_inferior_ptid() will be used by the cleanup machinery
3975 to restore the inferior_ptid value saved in a call to
3976 save_inferior_ptid(). */
3979 restore_inferior_ptid (void *arg)
3981 ptid_t *saved_ptid_ptr = arg;
3982 inferior_ptid = *saved_ptid_ptr;
3986 /* Save the value of inferior_ptid so that it may be restored by a
3987 later call to do_cleanups(). Returns the struct cleanup pointer
3988 needed for later doing the cleanup. */
3991 save_inferior_ptid (void)
3993 ptid_t *saved_ptid_ptr;
3995 saved_ptid_ptr = xmalloc (sizeof (ptid_t));
3996 *saved_ptid_ptr = inferior_ptid;
3997 return make_cleanup (restore_inferior_ptid, saved_ptid_ptr);
4002 _initialize_infrun (void)
4006 struct cmd_list_element *c;
4008 add_info ("signals", signals_info, _("\
4009 What debugger does when program gets various signals.\n\
4010 Specify a signal as argument to print info on that signal only."));
4011 add_info_alias ("handle", "signals", 0);
4013 add_com ("handle", class_run, handle_command, _("\
4014 Specify how to handle a signal.\n\
4015 Args are signals and actions to apply to those signals.\n\
4016 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
4017 from 1-15 are allowed for compatibility with old versions of GDB.\n\
4018 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
4019 The special arg \"all\" is recognized to mean all signals except those\n\
4020 used by the debugger, typically SIGTRAP and SIGINT.\n\
4021 Recognized actions include \"stop\", \"nostop\", \"print\", \"noprint\",\n\
4022 \"pass\", \"nopass\", \"ignore\", or \"noignore\".\n\
4023 Stop means reenter debugger if this signal happens (implies print).\n\
4024 Print means print a message if this signal happens.\n\
4025 Pass means let program see this signal; otherwise program doesn't know.\n\
4026 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
4027 Pass and Stop may be combined."));
4030 add_com ("lz", class_info, signals_info, _("\
4031 What debugger does when program gets various signals.\n\
4032 Specify a signal as argument to print info on that signal only."));
4033 add_com ("z", class_run, xdb_handle_command, _("\
4034 Specify how to handle a signal.\n\
4035 Args are signals and actions to apply to those signals.\n\
4036 Symbolic signals (e.g. SIGSEGV) are recommended but numeric signals\n\
4037 from 1-15 are allowed for compatibility with old versions of GDB.\n\
4038 Numeric ranges may be specified with the form LOW-HIGH (e.g. 1-5).\n\
4039 The special arg \"all\" is recognized to mean all signals except those\n\
4040 used by the debugger, typically SIGTRAP and SIGINT.\n\
4041 Recognized actions include \"s\" (toggles between stop and nostop), \n\
4042 \"r\" (toggles between print and noprint), \"i\" (toggles between pass and \
4043 nopass), \"Q\" (noprint)\n\
4044 Stop means reenter debugger if this signal happens (implies print).\n\
4045 Print means print a message if this signal happens.\n\
4046 Pass means let program see this signal; otherwise program doesn't know.\n\
4047 Ignore is a synonym for nopass and noignore is a synonym for pass.\n\
4048 Pass and Stop may be combined."));
4052 stop_command = add_cmd ("stop", class_obscure,
4053 not_just_help_class_command, _("\
4054 There is no `stop' command, but you can set a hook on `stop'.\n\
4055 This allows you to set a list of commands to be run each time execution\n\
4056 of the program stops."), &cmdlist);
4058 add_setshow_zinteger_cmd ("infrun", class_maintenance, &debug_infrun, _("\
4059 Set inferior debugging."), _("\
4060 Show inferior debugging."), _("\
4061 When non-zero, inferior specific debugging is enabled."),
4064 &setdebuglist, &showdebuglist);
4066 numsigs = (int) TARGET_SIGNAL_LAST;
4067 signal_stop = (unsigned char *) xmalloc (sizeof (signal_stop[0]) * numsigs);
4068 signal_print = (unsigned char *)
4069 xmalloc (sizeof (signal_print[0]) * numsigs);
4070 signal_program = (unsigned char *)
4071 xmalloc (sizeof (signal_program[0]) * numsigs);
4072 for (i = 0; i < numsigs; i++)
4075 signal_print[i] = 1;
4076 signal_program[i] = 1;
4079 /* Signals caused by debugger's own actions
4080 should not be given to the program afterwards. */
4081 signal_program[TARGET_SIGNAL_TRAP] = 0;
4082 signal_program[TARGET_SIGNAL_INT] = 0;
4084 /* Signals that are not errors should not normally enter the debugger. */
4085 signal_stop[TARGET_SIGNAL_ALRM] = 0;
4086 signal_print[TARGET_SIGNAL_ALRM] = 0;
4087 signal_stop[TARGET_SIGNAL_VTALRM] = 0;
4088 signal_print[TARGET_SIGNAL_VTALRM] = 0;
4089 signal_stop[TARGET_SIGNAL_PROF] = 0;
4090 signal_print[TARGET_SIGNAL_PROF] = 0;
4091 signal_stop[TARGET_SIGNAL_CHLD] = 0;
4092 signal_print[TARGET_SIGNAL_CHLD] = 0;
4093 signal_stop[TARGET_SIGNAL_IO] = 0;
4094 signal_print[TARGET_SIGNAL_IO] = 0;
4095 signal_stop[TARGET_SIGNAL_POLL] = 0;
4096 signal_print[TARGET_SIGNAL_POLL] = 0;
4097 signal_stop[TARGET_SIGNAL_URG] = 0;
4098 signal_print[TARGET_SIGNAL_URG] = 0;
4099 signal_stop[TARGET_SIGNAL_WINCH] = 0;
4100 signal_print[TARGET_SIGNAL_WINCH] = 0;
4102 /* These signals are used internally by user-level thread
4103 implementations. (See signal(5) on Solaris.) Like the above
4104 signals, a healthy program receives and handles them as part of
4105 its normal operation. */
4106 signal_stop[TARGET_SIGNAL_LWP] = 0;
4107 signal_print[TARGET_SIGNAL_LWP] = 0;
4108 signal_stop[TARGET_SIGNAL_WAITING] = 0;
4109 signal_print[TARGET_SIGNAL_WAITING] = 0;
4110 signal_stop[TARGET_SIGNAL_CANCEL] = 0;
4111 signal_print[TARGET_SIGNAL_CANCEL] = 0;
4113 add_setshow_zinteger_cmd ("stop-on-solib-events", class_support,
4114 &stop_on_solib_events, _("\
4115 Set stopping for shared library events."), _("\
4116 Show stopping for shared library events."), _("\
4117 If nonzero, gdb will give control to the user when the dynamic linker\n\
4118 notifies gdb of shared library events. The most common event of interest\n\
4119 to the user would be loading/unloading of a new library."),
4121 show_stop_on_solib_events,
4122 &setlist, &showlist);
4124 add_setshow_enum_cmd ("follow-fork-mode", class_run,
4125 follow_fork_mode_kind_names,
4126 &follow_fork_mode_string, _("\
4127 Set debugger response to a program call of fork or vfork."), _("\
4128 Show debugger response to a program call of fork or vfork."), _("\
4129 A fork or vfork creates a new process. follow-fork-mode can be:\n\
4130 parent - the original process is debugged after a fork\n\
4131 child - the new process is debugged after a fork\n\
4132 The unfollowed process will continue to run.\n\
4133 By default, the debugger will follow the parent process."),
4135 show_follow_fork_mode_string,
4136 &setlist, &showlist);
4138 add_setshow_enum_cmd ("scheduler-locking", class_run,
4139 scheduler_enums, &scheduler_mode, _("\
4140 Set mode for locking scheduler during execution."), _("\
4141 Show mode for locking scheduler during execution."), _("\
4142 off == no locking (threads may preempt at any time)\n\
4143 on == full locking (no thread except the current thread may run)\n\
4144 step == scheduler locked during every single-step operation.\n\
4145 In this mode, no other thread may run during a step command.\n\
4146 Other threads may run while stepping over a function call ('next')."),
4147 set_schedlock_func, /* traps on target vector */
4148 show_scheduler_mode,
4149 &setlist, &showlist);
4151 add_setshow_boolean_cmd ("step-mode", class_run, &step_stop_if_no_debug, _("\
4152 Set mode of the step operation."), _("\
4153 Show mode of the step operation."), _("\
4154 When set, doing a step over a function without debug line information\n\
4155 will stop at the first instruction of that function. Otherwise, the\n\
4156 function is skipped and the step command stops at a different source line."),
4158 show_step_stop_if_no_debug,
4159 &setlist, &showlist);
4161 /* ptid initializations */
4162 null_ptid = ptid_build (0, 0, 0);
4163 minus_one_ptid = ptid_build (-1, 0, 0);
4164 inferior_ptid = null_ptid;
4165 target_last_wait_ptid = minus_one_ptid;