1 /* Low level interface to ptrace, for the remote server for GDB.
2 Copyright 1995, 1996, 1998, 1999, 2000, 2001, 2002, 2003, 2004
3 Free Software Foundation, Inc.
5 This file is part of GDB.
7 This program is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2 of the License, or
10 (at your option) any later version.
12 This program is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with this program; if not, write to the Free Software
19 Foundation, Inc., 59 Temple Place - Suite 330,
20 Boston, MA 02111-1307, USA. */
23 #include "linux-low.h"
27 #include <sys/param.h>
29 #include <sys/ptrace.h>
32 #include <sys/ioctl.h>
39 /* ``all_threads'' is keyed by the LWP ID - it should be the thread ID instead,
40 however. This requires changing the ID in place when we go from !using_threads
41 to using_threads, immediately.
43 ``all_processes'' is keyed by the process ID - which on Linux is (presently)
44 the same as the LWP ID. */
46 struct inferior_list all_processes
;
48 /* FIXME this is a bit of a hack, and could be removed. */
51 /* FIXME make into a target method? */
54 static void linux_resume_one_process (struct inferior_list_entry
*entry
,
55 int step
, int signal
);
56 static void linux_resume (struct thread_resume
*resume_info
);
57 static void stop_all_processes (void);
58 static int linux_wait_for_event (struct thread_info
*child
);
60 struct pending_signals
63 struct pending_signals
*prev
;
66 #define PTRACE_ARG3_TYPE long
67 #define PTRACE_XFER_TYPE long
69 #ifdef HAVE_LINUX_REGSETS
70 static int use_regsets_p
= 1;
73 int debug_threads
= 0;
75 #define pid_of(proc) ((proc)->head.id)
77 /* FIXME: Delete eventually. */
78 #define inferior_pid (pid_of (get_thread_process (current_inferior)))
80 /* This function should only be called if the process got a SIGTRAP.
81 The SIGTRAP could mean several things.
83 On i386, where decr_pc_after_break is non-zero:
84 If we were single-stepping this process using PTRACE_SINGLESTEP,
85 we will get only the one SIGTRAP (even if the instruction we
86 stepped over was a breakpoint). The value of $eip will be the
88 If we continue the process using PTRACE_CONT, we will get a
89 SIGTRAP when we hit a breakpoint. The value of $eip will be
90 the instruction after the breakpoint (i.e. needs to be
91 decremented). If we report the SIGTRAP to GDB, we must also
92 report the undecremented PC. If we cancel the SIGTRAP, we
93 must resume at the decremented PC.
95 (Presumably, not yet tested) On a non-decr_pc_after_break machine
96 with hardware or kernel single-step:
97 If we single-step over a breakpoint instruction, our PC will
98 point at the following instruction. If we continue and hit a
99 breakpoint instruction, our PC will point at the breakpoint
105 CORE_ADDR stop_pc
= (*the_low_target
.get_pc
) ();
107 if (get_thread_process (current_inferior
)->stepping
)
110 return stop_pc
- the_low_target
.decr_pc_after_break
;
114 add_process (int pid
)
116 struct process_info
*process
;
118 process
= (struct process_info
*) malloc (sizeof (*process
));
119 memset (process
, 0, sizeof (*process
));
121 process
->head
.id
= pid
;
123 /* Default to tid == lwpid == pid. */
125 process
->lwpid
= pid
;
127 add_inferior_to_list (&all_processes
, &process
->head
);
132 /* Start an inferior process and returns its pid.
133 ALLARGS is a vector of program-name and args. */
136 linux_create_inferior (char *program
, char **allargs
)
143 perror_with_name ("fork");
147 ptrace (PTRACE_TRACEME
, 0, 0, 0);
149 signal (__SIGRTMIN
+ 1, SIG_DFL
);
153 execv (program
, allargs
);
155 fprintf (stderr
, "Cannot exec %s: %s.\n", program
,
161 new_process
= add_process (pid
);
162 add_thread (pid
, new_process
);
167 /* Attach to an inferior process. */
170 linux_attach_lwp (int pid
, int tid
)
172 struct process_info
*new_process
;
174 if (ptrace (PTRACE_ATTACH
, pid
, 0, 0) != 0)
176 fprintf (stderr
, "Cannot attach to process %d: %s (%d)\n", pid
,
177 strerror (errno
), errno
);
180 /* If we fail to attach to an LWP, just return. */
186 new_process
= (struct process_info
*) add_process (pid
);
187 add_thread (tid
, new_process
);
189 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
190 brings it to a halt. We should ignore that SIGSTOP and resume the process
191 (unless this is the first process, in which case the flag will be cleared
194 On the other hand, if we are currently trying to stop all threads, we
195 should treat the new thread as if we had sent it a SIGSTOP. This works
196 because we are guaranteed that add_process added us to the end of the
197 list, and so the new thread has not yet reached wait_for_sigstop (but
199 if (! stopping_threads
)
200 new_process
->stop_expected
= 1;
204 linux_attach (int pid
)
206 struct process_info
*process
;
208 linux_attach_lwp (pid
, pid
);
210 /* Don't ignore the initial SIGSTOP if we just attached to this process. */
211 process
= (struct process_info
*) find_inferior_id (&all_processes
, pid
);
212 process
->stop_expected
= 0;
217 /* Kill the inferior process. Make us have no inferior. */
220 linux_kill_one_process (struct inferior_list_entry
*entry
)
222 struct thread_info
*thread
= (struct thread_info
*) entry
;
223 struct process_info
*process
= get_thread_process (thread
);
228 ptrace (PTRACE_KILL
, pid_of (process
), 0, 0);
230 /* Make sure it died. The loop is most likely unnecessary. */
231 wstat
= linux_wait_for_event (thread
);
232 } while (WIFSTOPPED (wstat
));
238 for_each_inferior (&all_threads
, linux_kill_one_process
);
242 linux_detach_one_process (struct inferior_list_entry
*entry
)
244 struct thread_info
*thread
= (struct thread_info
*) entry
;
245 struct process_info
*process
= get_thread_process (thread
);
247 ptrace (PTRACE_DETACH
, pid_of (process
), 0, 0);
253 for_each_inferior (&all_threads
, linux_detach_one_process
);
256 /* Return nonzero if the given thread is still alive. */
258 linux_thread_alive (int tid
)
260 if (find_inferior_id (&all_threads
, tid
) != NULL
)
266 /* Return nonzero if this process stopped at a breakpoint which
267 no longer appears to be inserted. Also adjust the PC
268 appropriately to resume where the breakpoint used to be. */
270 check_removed_breakpoint (struct process_info
*event_child
)
273 struct thread_info
*saved_inferior
;
275 if (event_child
->pending_is_breakpoint
== 0)
279 fprintf (stderr
, "Checking for breakpoint.\n");
281 saved_inferior
= current_inferior
;
282 current_inferior
= get_process_thread (event_child
);
284 stop_pc
= get_stop_pc ();
286 /* If the PC has changed since we stopped, then we shouldn't do
287 anything. This happens if, for instance, GDB handled the
288 decr_pc_after_break subtraction itself. */
289 if (stop_pc
!= event_child
->pending_stop_pc
)
292 fprintf (stderr
, "Ignoring, PC was changed.\n");
294 event_child
->pending_is_breakpoint
= 0;
295 current_inferior
= saved_inferior
;
299 /* If the breakpoint is still there, we will report hitting it. */
300 if ((*the_low_target
.breakpoint_at
) (stop_pc
))
303 fprintf (stderr
, "Ignoring, breakpoint is still present.\n");
304 current_inferior
= saved_inferior
;
309 fprintf (stderr
, "Removed breakpoint.\n");
311 /* For decr_pc_after_break targets, here is where we perform the
312 decrement. We go immediately from this function to resuming,
313 and can not safely call get_stop_pc () again. */
314 if (the_low_target
.set_pc
!= NULL
)
315 (*the_low_target
.set_pc
) (stop_pc
);
317 /* We consumed the pending SIGTRAP. */
318 event_child
->pending_is_breakpoint
= 0;
319 event_child
->status_pending_p
= 0;
320 event_child
->status_pending
= 0;
322 current_inferior
= saved_inferior
;
326 /* Return 1 if this process has an interesting status pending. This function
327 may silently resume an inferior process. */
329 status_pending_p (struct inferior_list_entry
*entry
, void *dummy
)
331 struct process_info
*process
= (struct process_info
*) entry
;
333 if (process
->status_pending_p
)
334 if (check_removed_breakpoint (process
))
336 /* This thread was stopped at a breakpoint, and the breakpoint
337 is now gone. We were told to continue (or step...) all threads,
338 so GDB isn't trying to single-step past this breakpoint.
339 So instead of reporting the old SIGTRAP, pretend we got to
340 the breakpoint just after it was removed instead of just
341 before; resume the process. */
342 linux_resume_one_process (&process
->head
, 0, 0);
346 return process
->status_pending_p
;
350 linux_wait_for_process (struct process_info
**childp
, int *wstatp
)
353 int to_wait_for
= -1;
356 to_wait_for
= (*childp
)->lwpid
;
360 ret
= waitpid (to_wait_for
, wstatp
, WNOHANG
);
365 perror_with_name ("waitpid");
370 ret
= waitpid (to_wait_for
, wstatp
, WNOHANG
| __WCLONE
);
375 perror_with_name ("waitpid (WCLONE)");
384 && (!WIFSTOPPED (*wstatp
)
385 || (WSTOPSIG (*wstatp
) != 32
386 && WSTOPSIG (*wstatp
) != 33)))
387 fprintf (stderr
, "Got an event from %d (%x)\n", ret
, *wstatp
);
389 if (to_wait_for
== -1)
390 *childp
= (struct process_info
*) find_inferior_id (&all_processes
, ret
);
392 (*childp
)->stopped
= 1;
393 (*childp
)->pending_is_breakpoint
= 0;
396 && WIFSTOPPED (*wstatp
))
398 current_inferior
= (struct thread_info
*)
399 find_inferior_id (&all_threads
, (*childp
)->tid
);
400 /* For testing only; i386_stop_pc prints out a diagnostic. */
401 if (the_low_target
.get_pc
!= NULL
)
407 linux_wait_for_event (struct thread_info
*child
)
410 struct process_info
*event_child
;
413 /* Check for a process with a pending status. */
414 /* It is possible that the user changed the pending task's registers since
415 it stopped. We correctly handle the change of PC if we hit a breakpoint
416 (in check_removed_breakpoint); signals should be reported anyway. */
419 event_child
= (struct process_info
*)
420 find_inferior (&all_processes
, status_pending_p
, NULL
);
421 if (debug_threads
&& event_child
)
422 fprintf (stderr
, "Got a pending child %d\n", event_child
->lwpid
);
426 event_child
= get_thread_process (child
);
427 if (event_child
->status_pending_p
428 && check_removed_breakpoint (event_child
))
432 if (event_child
!= NULL
)
434 if (event_child
->status_pending_p
)
437 fprintf (stderr
, "Got an event from pending child %d (%04x)\n",
438 event_child
->lwpid
, event_child
->status_pending
);
439 wstat
= event_child
->status_pending
;
440 event_child
->status_pending_p
= 0;
441 event_child
->status_pending
= 0;
442 current_inferior
= get_process_thread (event_child
);
447 /* We only enter this loop if no process has a pending wait status. Thus
448 any action taken in response to a wait status inside this loop is
449 responding as soon as we detect the status, not after any pending
456 event_child
= get_thread_process (child
);
458 linux_wait_for_process (&event_child
, &wstat
);
460 if (event_child
== NULL
)
461 error ("event from unknown child");
463 current_inferior
= (struct thread_info
*)
464 find_inferior_id (&all_threads
, event_child
->tid
);
468 /* Check for thread exit. */
469 if (! WIFSTOPPED (wstat
))
472 fprintf (stderr
, "Thread %d (LWP %d) exiting\n",
473 event_child
->tid
, event_child
->head
.id
);
475 /* If the last thread is exiting, just return. */
476 if (all_threads
.head
== all_threads
.tail
)
479 dead_thread_notify (event_child
->tid
);
481 remove_inferior (&all_processes
, &event_child
->head
);
483 remove_thread (current_inferior
);
484 current_inferior
= (struct thread_info
*) all_threads
.head
;
486 /* If we were waiting for this particular child to do something...
487 well, it did something. */
491 /* Wait for a more interesting event. */
495 if (WIFSTOPPED (wstat
)
496 && WSTOPSIG (wstat
) == SIGSTOP
497 && event_child
->stop_expected
)
500 fprintf (stderr
, "Expected stop.\n");
501 event_child
->stop_expected
= 0;
502 linux_resume_one_process (&event_child
->head
,
503 event_child
->stepping
, 0);
507 /* FIXME drow/2002-06-09: Get signal numbers from the inferior's
509 if (WIFSTOPPED (wstat
)
510 && (WSTOPSIG (wstat
) == __SIGRTMIN
511 || WSTOPSIG (wstat
) == __SIGRTMIN
+ 1))
514 fprintf (stderr
, "Ignored signal %d for %d (LWP %d).\n",
515 WSTOPSIG (wstat
), event_child
->tid
,
516 event_child
->head
.id
);
517 linux_resume_one_process (&event_child
->head
,
518 event_child
->stepping
,
524 /* If this event was not handled above, and is not a SIGTRAP, report
526 if (!WIFSTOPPED (wstat
) || WSTOPSIG (wstat
) != SIGTRAP
)
529 /* If this target does not support breakpoints, we simply report the
530 SIGTRAP; it's of no concern to us. */
531 if (the_low_target
.get_pc
== NULL
)
534 stop_pc
= get_stop_pc ();
536 /* bp_reinsert will only be set if we were single-stepping.
537 Notice that we will resume the process after hitting
538 a gdbserver breakpoint; single-stepping to/over one
539 is not supported (yet). */
540 if (event_child
->bp_reinsert
!= 0)
543 fprintf (stderr
, "Reinserted breakpoint.\n");
544 reinsert_breakpoint (event_child
->bp_reinsert
);
545 event_child
->bp_reinsert
= 0;
547 /* Clear the single-stepping flag and SIGTRAP as we resume. */
548 linux_resume_one_process (&event_child
->head
, 0, 0);
553 fprintf (stderr
, "Hit a (non-reinsert) breakpoint.\n");
555 if (check_breakpoints (stop_pc
) != 0)
557 /* We hit one of our own breakpoints. We mark it as a pending
558 breakpoint, so that check_removed_breakpoint () will do the PC
559 adjustment for us at the appropriate time. */
560 event_child
->pending_is_breakpoint
= 1;
561 event_child
->pending_stop_pc
= stop_pc
;
563 /* Now we need to put the breakpoint back. We continue in the event
564 loop instead of simply replacing the breakpoint right away,
565 in order to not lose signals sent to the thread that hit the
566 breakpoint. Unfortunately this increases the window where another
567 thread could sneak past the removed breakpoint. For the current
568 use of server-side breakpoints (thread creation) this is
569 acceptable; but it needs to be considered before this breakpoint
570 mechanism can be used in more general ways. For some breakpoints
571 it may be necessary to stop all other threads, but that should
572 be avoided where possible.
574 If breakpoint_reinsert_addr is NULL, that means that we can
575 use PTRACE_SINGLESTEP on this platform. Uninsert the breakpoint,
576 mark it for reinsertion, and single-step.
578 Otherwise, call the target function to figure out where we need
579 our temporary breakpoint, create it, and continue executing this
581 if (the_low_target
.breakpoint_reinsert_addr
== NULL
)
583 event_child
->bp_reinsert
= stop_pc
;
584 uninsert_breakpoint (stop_pc
);
585 linux_resume_one_process (&event_child
->head
, 1, 0);
589 reinsert_breakpoint_by_bp
590 (stop_pc
, (*the_low_target
.breakpoint_reinsert_addr
) ());
591 linux_resume_one_process (&event_child
->head
, 0, 0);
597 /* If we were single-stepping, we definitely want to report the
598 SIGTRAP. The single-step operation has completed, so also
599 clear the stepping flag; in general this does not matter,
600 because the SIGTRAP will be reported to the client, which
601 will give us a new action for this thread, but clear it for
602 consistency anyway. It's safe to clear the stepping flag
603 because the only consumer of get_stop_pc () after this point
604 is check_removed_breakpoint, and pending_is_breakpoint is not
605 set. It might be wiser to use a step_completed flag instead. */
606 if (event_child
->stepping
)
608 event_child
->stepping
= 0;
612 /* A SIGTRAP that we can't explain. It may have been a breakpoint.
613 Check if it is a breakpoint, and if so mark the process information
614 accordingly. This will handle both the necessary fiddling with the
615 PC on decr_pc_after_break targets and suppressing extra threads
616 hitting a breakpoint if two hit it at once and then GDB removes it
617 after the first is reported. Arguably it would be better to report
618 multiple threads hitting breakpoints simultaneously, but the current
619 remote protocol does not allow this. */
620 if ((*the_low_target
.breakpoint_at
) (stop_pc
))
622 event_child
->pending_is_breakpoint
= 1;
623 event_child
->pending_stop_pc
= stop_pc
;
633 /* Wait for process, returns status. */
636 linux_wait (char *status
)
639 struct thread_info
*child
= NULL
;
642 /* If we were only supposed to resume one thread, only wait for
643 that thread - if it's still alive. If it died, however - which
644 can happen if we're coming from the thread death case below -
645 then we need to make sure we restart the other threads. We could
646 pick a thread at random or restart all; restarting all is less
650 child
= (struct thread_info
*) find_inferior_id (&all_threads
,
653 /* No stepping, no signal - unless one is pending already, of course. */
656 struct thread_resume resume_info
;
657 resume_info
.thread
= -1;
658 resume_info
.step
= resume_info
.sig
= resume_info
.leave_stopped
= 0;
659 linux_resume (&resume_info
);
665 w
= linux_wait_for_event (child
);
666 stop_all_processes ();
669 /* If we are waiting for a particular child, and it exited,
670 linux_wait_for_event will return its exit status. Similarly if
671 the last child exited. If this is not the last child, however,
672 do not report it as exited until there is a 'thread exited' response
673 available in the remote protocol. Instead, just wait for another event.
674 This should be safe, because if the thread crashed we will already
675 have reported the termination signal to GDB; that should stop any
676 in-progress stepping operations, etc.
678 Report the exit status of the last thread to exit. This matches
679 LinuxThreads' behavior. */
681 if (all_threads
.head
== all_threads
.tail
)
685 fprintf (stderr
, "\nChild exited with retcode = %x \n", WEXITSTATUS (w
));
688 return ((unsigned char) WEXITSTATUS (w
));
690 else if (!WIFSTOPPED (w
))
692 fprintf (stderr
, "\nChild terminated with signal = %x \n", WTERMSIG (w
));
695 return ((unsigned char) WTERMSIG (w
));
705 return ((unsigned char) WSTOPSIG (w
));
709 send_sigstop (struct inferior_list_entry
*entry
)
711 struct process_info
*process
= (struct process_info
*) entry
;
713 if (process
->stopped
)
716 /* If we already have a pending stop signal for this process, don't
718 if (process
->stop_expected
)
720 process
->stop_expected
= 0;
725 fprintf (stderr
, "Sending sigstop to process %d\n", process
->head
.id
);
727 kill (process
->head
.id
, SIGSTOP
);
728 process
->sigstop_sent
= 1;
732 wait_for_sigstop (struct inferior_list_entry
*entry
)
734 struct process_info
*process
= (struct process_info
*) entry
;
735 struct thread_info
*saved_inferior
, *thread
;
736 int wstat
, saved_tid
;
738 if (process
->stopped
)
741 saved_inferior
= current_inferior
;
742 saved_tid
= ((struct inferior_list_entry
*) saved_inferior
)->id
;
743 thread
= (struct thread_info
*) find_inferior_id (&all_threads
,
745 wstat
= linux_wait_for_event (thread
);
747 /* If we stopped with a non-SIGSTOP signal, save it for later
748 and record the pending SIGSTOP. If the process exited, just
750 if (WIFSTOPPED (wstat
)
751 && WSTOPSIG (wstat
) != SIGSTOP
)
754 fprintf (stderr
, "Stopped with non-sigstop signal\n");
755 process
->status_pending_p
= 1;
756 process
->status_pending
= wstat
;
757 process
->stop_expected
= 1;
760 if (linux_thread_alive (saved_tid
))
761 current_inferior
= saved_inferior
;
765 fprintf (stderr
, "Previously current thread died.\n");
767 /* Set a valid thread as current. */
768 set_desired_inferior (0);
773 stop_all_processes (void)
775 stopping_threads
= 1;
776 for_each_inferior (&all_processes
, send_sigstop
);
777 for_each_inferior (&all_processes
, wait_for_sigstop
);
778 stopping_threads
= 0;
781 /* Resume execution of the inferior process.
782 If STEP is nonzero, single-step it.
783 If SIGNAL is nonzero, give it that signal. */
786 linux_resume_one_process (struct inferior_list_entry
*entry
,
787 int step
, int signal
)
789 struct process_info
*process
= (struct process_info
*) entry
;
790 struct thread_info
*saved_inferior
;
792 if (process
->stopped
== 0)
795 /* If we have pending signals or status, and a new signal, enqueue the
796 signal. Also enqueue the signal if we are waiting to reinsert a
797 breakpoint; it will be picked up again below. */
799 && (process
->status_pending_p
|| process
->pending_signals
!= NULL
800 || process
->bp_reinsert
!= 0))
802 struct pending_signals
*p_sig
;
803 p_sig
= malloc (sizeof (*p_sig
));
804 p_sig
->prev
= process
->pending_signals
;
805 p_sig
->signal
= signal
;
806 process
->pending_signals
= p_sig
;
809 if (process
->status_pending_p
&& !check_removed_breakpoint (process
))
812 saved_inferior
= current_inferior
;
813 current_inferior
= get_process_thread (process
);
816 fprintf (stderr
, "Resuming process %d (%s, signal %d, stop %s)\n", inferior_pid
,
817 step
? "step" : "continue", signal
,
818 process
->stop_expected
? "expected" : "not expected");
820 /* This bit needs some thinking about. If we get a signal that
821 we must report while a single-step reinsert is still pending,
822 we often end up resuming the thread. It might be better to
823 (ew) allow a stack of pending events; then we could be sure that
824 the reinsert happened right away and not lose any signals.
826 Making this stack would also shrink the window in which breakpoints are
827 uninserted (see comment in linux_wait_for_process) but not enough for
828 complete correctness, so it won't solve that problem. It may be
829 worthwhile just to solve this one, however. */
830 if (process
->bp_reinsert
!= 0)
833 fprintf (stderr
, " pending reinsert at %08lx", (long)process
->bp_reinsert
);
835 fprintf (stderr
, "BAD - reinserting but not stepping.\n");
838 /* Postpone any pending signal. It was enqueued above. */
842 check_removed_breakpoint (process
);
844 if (debug_threads
&& the_low_target
.get_pc
!= NULL
)
846 fprintf (stderr
, " ");
847 (long) (*the_low_target
.get_pc
) ();
850 /* If we have pending signals, consume one unless we are trying to reinsert
852 if (process
->pending_signals
!= NULL
&& process
->bp_reinsert
== 0)
854 struct pending_signals
**p_sig
;
856 p_sig
= &process
->pending_signals
;
857 while ((*p_sig
)->prev
!= NULL
)
858 p_sig
= &(*p_sig
)->prev
;
860 signal
= (*p_sig
)->signal
;
865 regcache_invalidate_one ((struct inferior_list_entry
*)
866 get_process_thread (process
));
868 process
->stopped
= 0;
869 process
->stepping
= step
;
870 ptrace (step
? PTRACE_SINGLESTEP
: PTRACE_CONT
, process
->lwpid
, 0, signal
);
872 current_inferior
= saved_inferior
;
874 perror_with_name ("ptrace");
877 static struct thread_resume
*resume_ptr
;
879 /* This function is called once per thread. We look up the thread
880 in RESUME_PTR, and mark the thread with a pointer to the appropriate
883 This algorithm is O(threads * resume elements), but resume elements
884 is small (and will remain small at least until GDB supports thread
887 linux_set_resume_request (struct inferior_list_entry
*entry
)
889 struct process_info
*process
;
890 struct thread_info
*thread
;
893 thread
= (struct thread_info
*) entry
;
894 process
= get_thread_process (thread
);
897 while (resume_ptr
[ndx
].thread
!= -1 && resume_ptr
[ndx
].thread
!= entry
->id
)
900 process
->resume
= &resume_ptr
[ndx
];
903 /* This function is called once per thread. We check the thread's resume
904 request, which will tell us whether to resume, step, or leave the thread
905 stopped; and what signal, if any, it should be sent. For threads which
906 we aren't explicitly told otherwise, we preserve the stepping flag; this
907 is used for stepping over gdbserver-placed breakpoints. */
910 linux_continue_one_thread (struct inferior_list_entry
*entry
)
912 struct process_info
*process
;
913 struct thread_info
*thread
;
916 thread
= (struct thread_info
*) entry
;
917 process
= get_thread_process (thread
);
919 if (process
->resume
->leave_stopped
)
922 if (process
->resume
->thread
== -1)
923 step
= process
->stepping
|| process
->resume
->step
;
925 step
= process
->resume
->step
;
927 linux_resume_one_process (&process
->head
, step
, process
->resume
->sig
);
929 process
->resume
= NULL
;
932 /* This function is called once per thread. We check the thread's resume
933 request, which will tell us whether to resume, step, or leave the thread
934 stopped; and what signal, if any, it should be sent. We queue any needed
935 signals, since we won't actually resume. We already have a pending event
936 to report, so we don't need to preserve any step requests; they should
937 be re-issued if necessary. */
940 linux_queue_one_thread (struct inferior_list_entry
*entry
)
942 struct process_info
*process
;
943 struct thread_info
*thread
;
945 thread
= (struct thread_info
*) entry
;
946 process
= get_thread_process (thread
);
948 if (process
->resume
->leave_stopped
)
951 /* If we have a new signal, enqueue the signal. */
952 if (process
->resume
->sig
!= 0)
954 struct pending_signals
*p_sig
;
955 p_sig
= malloc (sizeof (*p_sig
));
956 p_sig
->prev
= process
->pending_signals
;
957 p_sig
->signal
= process
->resume
->sig
;
958 process
->pending_signals
= p_sig
;
961 process
->resume
= NULL
;
964 /* Set DUMMY if this process has an interesting status pending. */
966 resume_status_pending_p (struct inferior_list_entry
*entry
, void *flag_p
)
968 struct process_info
*process
= (struct process_info
*) entry
;
970 /* Processes which will not be resumed are not interesting, because
971 we might not wait for them next time through linux_wait. */
972 if (process
->resume
->leave_stopped
)
975 /* If this thread has a removed breakpoint, we won't have any
976 events to report later, so check now. check_removed_breakpoint
977 may clear status_pending_p. We avoid calling check_removed_breakpoint
978 for any thread that we are not otherwise going to resume - this
979 lets us preserve stopped status when two threads hit a breakpoint.
980 GDB removes the breakpoint to single-step a particular thread
981 past it, then re-inserts it and resumes all threads. We want
982 to report the second thread without resuming it in the interim. */
983 if (process
->status_pending_p
)
984 check_removed_breakpoint (process
);
986 if (process
->status_pending_p
)
987 * (int *) flag_p
= 1;
993 linux_resume (struct thread_resume
*resume_info
)
997 /* Yes, the use of a global here is rather ugly. */
998 resume_ptr
= resume_info
;
1000 for_each_inferior (&all_threads
, linux_set_resume_request
);
1002 /* If there is a thread which would otherwise be resumed, which
1003 has a pending status, then don't resume any threads - we can just
1004 report the pending status. Make sure to queue any signals
1005 that would otherwise be sent. */
1007 find_inferior (&all_processes
, resume_status_pending_p
, &pending_flag
);
1012 fprintf (stderr
, "Not resuming, pending status\n");
1014 fprintf (stderr
, "Resuming, no pending status\n");
1018 for_each_inferior (&all_threads
, linux_queue_one_thread
);
1023 for_each_inferior (&all_threads
, linux_continue_one_thread
);
1027 #ifdef HAVE_LINUX_USRREGS
1030 register_addr (int regnum
)
1034 if (regnum
< 0 || regnum
>= the_low_target
.num_regs
)
1035 error ("Invalid register number %d.", regnum
);
1037 addr
= the_low_target
.regmap
[regnum
];
1042 /* Fetch one register. */
1044 fetch_register (int regno
)
1050 if (regno
>= the_low_target
.num_regs
)
1052 if ((*the_low_target
.cannot_fetch_register
) (regno
))
1055 regaddr
= register_addr (regno
);
1058 buf
= alloca (register_size (regno
));
1059 for (i
= 0; i
< register_size (regno
); i
+= sizeof (PTRACE_XFER_TYPE
))
1062 *(PTRACE_XFER_TYPE
*) (buf
+ i
) =
1063 ptrace (PTRACE_PEEKUSER
, inferior_pid
, (PTRACE_ARG3_TYPE
) regaddr
, 0);
1064 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
1067 /* Warning, not error, in case we are attached; sometimes the
1068 kernel doesn't let us at the registers. */
1069 char *err
= strerror (errno
);
1070 char *msg
= alloca (strlen (err
) + 128);
1071 sprintf (msg
, "reading register %d: %s", regno
, err
);
1076 supply_register (regno
, buf
);
1081 /* Fetch all registers, or just one, from the child process. */
1083 usr_fetch_inferior_registers (int regno
)
1085 if (regno
== -1 || regno
== 0)
1086 for (regno
= 0; regno
< the_low_target
.num_regs
; regno
++)
1087 fetch_register (regno
);
1089 fetch_register (regno
);
1092 /* Store our register values back into the inferior.
1093 If REGNO is -1, do this for all registers.
1094 Otherwise, REGNO specifies which register (so we can save time). */
1096 usr_store_inferior_registers (int regno
)
1104 if (regno
>= the_low_target
.num_regs
)
1107 if ((*the_low_target
.cannot_store_register
) (regno
) == 1)
1110 regaddr
= register_addr (regno
);
1114 buf
= alloca (register_size (regno
));
1115 collect_register (regno
, buf
);
1116 for (i
= 0; i
< register_size (regno
); i
+= sizeof (PTRACE_XFER_TYPE
))
1119 ptrace (PTRACE_POKEUSER
, inferior_pid
, (PTRACE_ARG3_TYPE
) regaddr
,
1120 *(PTRACE_XFER_TYPE
*) (buf
+ i
));
1123 if ((*the_low_target
.cannot_store_register
) (regno
) == 0)
1125 char *err
= strerror (errno
);
1126 char *msg
= alloca (strlen (err
) + 128);
1127 sprintf (msg
, "writing register %d: %s",
1133 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
1137 for (regno
= 0; regno
< the_low_target
.num_regs
; regno
++)
1138 usr_store_inferior_registers (regno
);
1140 #endif /* HAVE_LINUX_USRREGS */
1144 #ifdef HAVE_LINUX_REGSETS
1147 regsets_fetch_inferior_registers ()
1149 struct regset_info
*regset
;
1151 regset
= target_regsets
;
1153 while (regset
->size
>= 0)
1158 if (regset
->size
== 0)
1164 buf
= malloc (regset
->size
);
1165 res
= ptrace (regset
->get_request
, inferior_pid
, 0, buf
);
1170 /* If we get EIO on the first regset, do not try regsets again.
1171 If we get EIO on a later regset, disable that regset. */
1172 if (regset
== target_regsets
)
1186 sprintf (s
, "ptrace(regsets_fetch_inferior_registers) PID=%d",
1191 regset
->store_function (buf
);
1198 regsets_store_inferior_registers ()
1200 struct regset_info
*regset
;
1202 regset
= target_regsets
;
1204 while (regset
->size
>= 0)
1209 if (regset
->size
== 0)
1215 buf
= malloc (regset
->size
);
1216 regset
->fill_function (buf
);
1217 res
= ptrace (regset
->set_request
, inferior_pid
, 0, buf
);
1222 /* If we get EIO on the first regset, do not try regsets again.
1223 If we get EIO on a later regset, disable that regset. */
1224 if (regset
== target_regsets
)
1237 perror ("Warning: ptrace(regsets_store_inferior_registers)");
1246 #endif /* HAVE_LINUX_REGSETS */
1250 linux_fetch_registers (int regno
)
1252 #ifdef HAVE_LINUX_REGSETS
1255 if (regsets_fetch_inferior_registers () == 0)
1259 #ifdef HAVE_LINUX_USRREGS
1260 usr_fetch_inferior_registers (regno
);
1265 linux_store_registers (int regno
)
1267 #ifdef HAVE_LINUX_REGSETS
1270 if (regsets_store_inferior_registers () == 0)
1274 #ifdef HAVE_LINUX_USRREGS
1275 usr_store_inferior_registers (regno
);
1280 /* Copy LEN bytes from inferior's memory starting at MEMADDR
1281 to debugger memory starting at MYADDR. */
1284 linux_read_memory (CORE_ADDR memaddr
, char *myaddr
, int len
)
1287 /* Round starting address down to longword boundary. */
1288 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
1289 /* Round ending address up; get number of longwords that makes. */
1291 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
1292 / sizeof (PTRACE_XFER_TYPE
);
1293 /* Allocate buffer of that many longwords. */
1294 register PTRACE_XFER_TYPE
*buffer
1295 = (PTRACE_XFER_TYPE
*) alloca (count
* sizeof (PTRACE_XFER_TYPE
));
1297 /* Read all the longwords */
1298 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
1301 buffer
[i
] = ptrace (PTRACE_PEEKTEXT
, inferior_pid
, (PTRACE_ARG3_TYPE
) addr
, 0);
1306 /* Copy appropriate bytes out of the buffer. */
1307 memcpy (myaddr
, (char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)), len
);
1312 /* Copy LEN bytes of data from debugger memory at MYADDR
1313 to inferior's memory at MEMADDR.
1314 On failure (cannot write the inferior)
1315 returns the value of errno. */
1318 linux_write_memory (CORE_ADDR memaddr
, const char *myaddr
, int len
)
1321 /* Round starting address down to longword boundary. */
1322 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
1323 /* Round ending address up; get number of longwords that makes. */
1325 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1) / sizeof (PTRACE_XFER_TYPE
);
1326 /* Allocate buffer of that many longwords. */
1327 register PTRACE_XFER_TYPE
*buffer
= (PTRACE_XFER_TYPE
*) alloca (count
* sizeof (PTRACE_XFER_TYPE
));
1332 fprintf (stderr
, "Writing %02x to %08lx\n", (unsigned)myaddr
[0], (long)memaddr
);
1335 /* Fill start and end extra bytes of buffer with existing memory data. */
1337 buffer
[0] = ptrace (PTRACE_PEEKTEXT
, inferior_pid
,
1338 (PTRACE_ARG3_TYPE
) addr
, 0);
1343 = ptrace (PTRACE_PEEKTEXT
, inferior_pid
,
1344 (PTRACE_ARG3_TYPE
) (addr
+ (count
- 1)
1345 * sizeof (PTRACE_XFER_TYPE
)),
1349 /* Copy data to be written over corresponding part of buffer */
1351 memcpy ((char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)), myaddr
, len
);
1353 /* Write the entire buffer. */
1355 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
1358 ptrace (PTRACE_POKETEXT
, inferior_pid
, (PTRACE_ARG3_TYPE
) addr
, buffer
[i
]);
1367 linux_look_up_symbols (void)
1369 #ifdef USE_THREAD_DB
1373 using_threads
= thread_db_init ();
1378 linux_send_signal (int signum
)
1380 extern int signal_pid
;
1382 if (cont_thread
> 0)
1384 struct process_info
*process
;
1386 process
= get_thread_process (current_inferior
);
1387 kill (process
->lwpid
, signum
);
1390 kill (signal_pid
, signum
);
1393 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
1394 to debugger memory starting at MYADDR. */
1397 linux_read_auxv (CORE_ADDR offset
, char *myaddr
, unsigned int len
)
1399 char filename
[PATH_MAX
];
1402 snprintf (filename
, sizeof filename
, "/proc/%d/auxv", inferior_pid
);
1404 fd
= open (filename
, O_RDONLY
);
1408 if (offset
!= (CORE_ADDR
) 0
1409 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
1412 n
= read (fd
, myaddr
, len
);
1420 static struct target_ops linux_target_ops
= {
1421 linux_create_inferior
,
1428 linux_fetch_registers
,
1429 linux_store_registers
,
1432 linux_look_up_symbols
,
1438 linux_init_signals ()
1440 /* FIXME drow/2002-06-09: As above, we should check with LinuxThreads
1441 to find what the cancel signal actually is. */
1442 signal (__SIGRTMIN
+1, SIG_IGN
);
1446 initialize_low (void)
1449 set_target_ops (&linux_target_ops
);
1450 set_breakpoint_data (the_low_target
.breakpoint
,
1451 the_low_target
.breakpoint_len
);
1453 linux_init_signals ();