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 free (all_processes
.head
);
689 all_processes
.head
= all_processes
.tail
= NULL
;
690 return ((unsigned char) WEXITSTATUS (w
));
692 else if (!WIFSTOPPED (w
))
694 fprintf (stderr
, "\nChild terminated with signal = %x \n", WTERMSIG (w
));
697 free (all_processes
.head
);
698 all_processes
.head
= all_processes
.tail
= NULL
;
699 return ((unsigned char) WTERMSIG (w
));
709 return ((unsigned char) WSTOPSIG (w
));
713 send_sigstop (struct inferior_list_entry
*entry
)
715 struct process_info
*process
= (struct process_info
*) entry
;
717 if (process
->stopped
)
720 /* If we already have a pending stop signal for this process, don't
722 if (process
->stop_expected
)
724 process
->stop_expected
= 0;
729 fprintf (stderr
, "Sending sigstop to process %d\n", process
->head
.id
);
731 kill (process
->head
.id
, SIGSTOP
);
732 process
->sigstop_sent
= 1;
736 wait_for_sigstop (struct inferior_list_entry
*entry
)
738 struct process_info
*process
= (struct process_info
*) entry
;
739 struct thread_info
*saved_inferior
, *thread
;
740 int wstat
, saved_tid
;
742 if (process
->stopped
)
745 saved_inferior
= current_inferior
;
746 saved_tid
= ((struct inferior_list_entry
*) saved_inferior
)->id
;
747 thread
= (struct thread_info
*) find_inferior_id (&all_threads
,
749 wstat
= linux_wait_for_event (thread
);
751 /* If we stopped with a non-SIGSTOP signal, save it for later
752 and record the pending SIGSTOP. If the process exited, just
754 if (WIFSTOPPED (wstat
)
755 && WSTOPSIG (wstat
) != SIGSTOP
)
758 fprintf (stderr
, "Stopped with non-sigstop signal\n");
759 process
->status_pending_p
= 1;
760 process
->status_pending
= wstat
;
761 process
->stop_expected
= 1;
764 if (linux_thread_alive (saved_tid
))
765 current_inferior
= saved_inferior
;
769 fprintf (stderr
, "Previously current thread died.\n");
771 /* Set a valid thread as current. */
772 set_desired_inferior (0);
777 stop_all_processes (void)
779 stopping_threads
= 1;
780 for_each_inferior (&all_processes
, send_sigstop
);
781 for_each_inferior (&all_processes
, wait_for_sigstop
);
782 stopping_threads
= 0;
785 /* Resume execution of the inferior process.
786 If STEP is nonzero, single-step it.
787 If SIGNAL is nonzero, give it that signal. */
790 linux_resume_one_process (struct inferior_list_entry
*entry
,
791 int step
, int signal
)
793 struct process_info
*process
= (struct process_info
*) entry
;
794 struct thread_info
*saved_inferior
;
796 if (process
->stopped
== 0)
799 /* If we have pending signals or status, and a new signal, enqueue the
800 signal. Also enqueue the signal if we are waiting to reinsert a
801 breakpoint; it will be picked up again below. */
803 && (process
->status_pending_p
|| process
->pending_signals
!= NULL
804 || process
->bp_reinsert
!= 0))
806 struct pending_signals
*p_sig
;
807 p_sig
= malloc (sizeof (*p_sig
));
808 p_sig
->prev
= process
->pending_signals
;
809 p_sig
->signal
= signal
;
810 process
->pending_signals
= p_sig
;
813 if (process
->status_pending_p
&& !check_removed_breakpoint (process
))
816 saved_inferior
= current_inferior
;
817 current_inferior
= get_process_thread (process
);
820 fprintf (stderr
, "Resuming process %d (%s, signal %d, stop %s)\n", inferior_pid
,
821 step
? "step" : "continue", signal
,
822 process
->stop_expected
? "expected" : "not expected");
824 /* This bit needs some thinking about. If we get a signal that
825 we must report while a single-step reinsert is still pending,
826 we often end up resuming the thread. It might be better to
827 (ew) allow a stack of pending events; then we could be sure that
828 the reinsert happened right away and not lose any signals.
830 Making this stack would also shrink the window in which breakpoints are
831 uninserted (see comment in linux_wait_for_process) but not enough for
832 complete correctness, so it won't solve that problem. It may be
833 worthwhile just to solve this one, however. */
834 if (process
->bp_reinsert
!= 0)
837 fprintf (stderr
, " pending reinsert at %08lx", (long)process
->bp_reinsert
);
839 fprintf (stderr
, "BAD - reinserting but not stepping.\n");
842 /* Postpone any pending signal. It was enqueued above. */
846 check_removed_breakpoint (process
);
848 if (debug_threads
&& the_low_target
.get_pc
!= NULL
)
850 fprintf (stderr
, " ");
851 (long) (*the_low_target
.get_pc
) ();
854 /* If we have pending signals, consume one unless we are trying to reinsert
856 if (process
->pending_signals
!= NULL
&& process
->bp_reinsert
== 0)
858 struct pending_signals
**p_sig
;
860 p_sig
= &process
->pending_signals
;
861 while ((*p_sig
)->prev
!= NULL
)
862 p_sig
= &(*p_sig
)->prev
;
864 signal
= (*p_sig
)->signal
;
869 regcache_invalidate_one ((struct inferior_list_entry
*)
870 get_process_thread (process
));
872 process
->stopped
= 0;
873 process
->stepping
= step
;
874 ptrace (step
? PTRACE_SINGLESTEP
: PTRACE_CONT
, process
->lwpid
, 0, signal
);
876 current_inferior
= saved_inferior
;
878 perror_with_name ("ptrace");
881 static struct thread_resume
*resume_ptr
;
883 /* This function is called once per thread. We look up the thread
884 in RESUME_PTR, and mark the thread with a pointer to the appropriate
887 This algorithm is O(threads * resume elements), but resume elements
888 is small (and will remain small at least until GDB supports thread
891 linux_set_resume_request (struct inferior_list_entry
*entry
)
893 struct process_info
*process
;
894 struct thread_info
*thread
;
897 thread
= (struct thread_info
*) entry
;
898 process
= get_thread_process (thread
);
901 while (resume_ptr
[ndx
].thread
!= -1 && resume_ptr
[ndx
].thread
!= entry
->id
)
904 process
->resume
= &resume_ptr
[ndx
];
907 /* This function is called once per thread. We check the thread's resume
908 request, which will tell us whether to resume, step, or leave the thread
909 stopped; and what signal, if any, it should be sent. For threads which
910 we aren't explicitly told otherwise, we preserve the stepping flag; this
911 is used for stepping over gdbserver-placed breakpoints. */
914 linux_continue_one_thread (struct inferior_list_entry
*entry
)
916 struct process_info
*process
;
917 struct thread_info
*thread
;
920 thread
= (struct thread_info
*) entry
;
921 process
= get_thread_process (thread
);
923 if (process
->resume
->leave_stopped
)
926 if (process
->resume
->thread
== -1)
927 step
= process
->stepping
|| process
->resume
->step
;
929 step
= process
->resume
->step
;
931 linux_resume_one_process (&process
->head
, step
, process
->resume
->sig
);
933 process
->resume
= NULL
;
936 /* This function is called once per thread. We check the thread's resume
937 request, which will tell us whether to resume, step, or leave the thread
938 stopped; and what signal, if any, it should be sent. We queue any needed
939 signals, since we won't actually resume. We already have a pending event
940 to report, so we don't need to preserve any step requests; they should
941 be re-issued if necessary. */
944 linux_queue_one_thread (struct inferior_list_entry
*entry
)
946 struct process_info
*process
;
947 struct thread_info
*thread
;
949 thread
= (struct thread_info
*) entry
;
950 process
= get_thread_process (thread
);
952 if (process
->resume
->leave_stopped
)
955 /* If we have a new signal, enqueue the signal. */
956 if (process
->resume
->sig
!= 0)
958 struct pending_signals
*p_sig
;
959 p_sig
= malloc (sizeof (*p_sig
));
960 p_sig
->prev
= process
->pending_signals
;
961 p_sig
->signal
= process
->resume
->sig
;
962 process
->pending_signals
= p_sig
;
965 process
->resume
= NULL
;
968 /* Set DUMMY if this process has an interesting status pending. */
970 resume_status_pending_p (struct inferior_list_entry
*entry
, void *flag_p
)
972 struct process_info
*process
= (struct process_info
*) entry
;
974 /* Processes which will not be resumed are not interesting, because
975 we might not wait for them next time through linux_wait. */
976 if (process
->resume
->leave_stopped
)
979 /* If this thread has a removed breakpoint, we won't have any
980 events to report later, so check now. check_removed_breakpoint
981 may clear status_pending_p. We avoid calling check_removed_breakpoint
982 for any thread that we are not otherwise going to resume - this
983 lets us preserve stopped status when two threads hit a breakpoint.
984 GDB removes the breakpoint to single-step a particular thread
985 past it, then re-inserts it and resumes all threads. We want
986 to report the second thread without resuming it in the interim. */
987 if (process
->status_pending_p
)
988 check_removed_breakpoint (process
);
990 if (process
->status_pending_p
)
991 * (int *) flag_p
= 1;
997 linux_resume (struct thread_resume
*resume_info
)
1001 /* Yes, the use of a global here is rather ugly. */
1002 resume_ptr
= resume_info
;
1004 for_each_inferior (&all_threads
, linux_set_resume_request
);
1006 /* If there is a thread which would otherwise be resumed, which
1007 has a pending status, then don't resume any threads - we can just
1008 report the pending status. Make sure to queue any signals
1009 that would otherwise be sent. */
1011 find_inferior (&all_processes
, resume_status_pending_p
, &pending_flag
);
1016 fprintf (stderr
, "Not resuming, pending status\n");
1018 fprintf (stderr
, "Resuming, no pending status\n");
1022 for_each_inferior (&all_threads
, linux_queue_one_thread
);
1027 for_each_inferior (&all_threads
, linux_continue_one_thread
);
1031 #ifdef HAVE_LINUX_USRREGS
1034 register_addr (int regnum
)
1038 if (regnum
< 0 || regnum
>= the_low_target
.num_regs
)
1039 error ("Invalid register number %d.", regnum
);
1041 addr
= the_low_target
.regmap
[regnum
];
1046 /* Fetch one register. */
1048 fetch_register (int regno
)
1054 if (regno
>= the_low_target
.num_regs
)
1056 if ((*the_low_target
.cannot_fetch_register
) (regno
))
1059 regaddr
= register_addr (regno
);
1062 buf
= alloca (register_size (regno
));
1063 for (i
= 0; i
< register_size (regno
); i
+= sizeof (PTRACE_XFER_TYPE
))
1066 *(PTRACE_XFER_TYPE
*) (buf
+ i
) =
1067 ptrace (PTRACE_PEEKUSER
, inferior_pid
, (PTRACE_ARG3_TYPE
) regaddr
, 0);
1068 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
1071 /* Warning, not error, in case we are attached; sometimes the
1072 kernel doesn't let us at the registers. */
1073 char *err
= strerror (errno
);
1074 char *msg
= alloca (strlen (err
) + 128);
1075 sprintf (msg
, "reading register %d: %s", regno
, err
);
1080 supply_register (regno
, buf
);
1085 /* Fetch all registers, or just one, from the child process. */
1087 usr_fetch_inferior_registers (int regno
)
1089 if (regno
== -1 || regno
== 0)
1090 for (regno
= 0; regno
< the_low_target
.num_regs
; regno
++)
1091 fetch_register (regno
);
1093 fetch_register (regno
);
1096 /* Store our register values back into the inferior.
1097 If REGNO is -1, do this for all registers.
1098 Otherwise, REGNO specifies which register (so we can save time). */
1100 usr_store_inferior_registers (int regno
)
1108 if (regno
>= the_low_target
.num_regs
)
1111 if ((*the_low_target
.cannot_store_register
) (regno
) == 1)
1114 regaddr
= register_addr (regno
);
1118 buf
= alloca (register_size (regno
));
1119 collect_register (regno
, buf
);
1120 for (i
= 0; i
< register_size (regno
); i
+= sizeof (PTRACE_XFER_TYPE
))
1123 ptrace (PTRACE_POKEUSER
, inferior_pid
, (PTRACE_ARG3_TYPE
) regaddr
,
1124 *(PTRACE_XFER_TYPE
*) (buf
+ i
));
1127 if ((*the_low_target
.cannot_store_register
) (regno
) == 0)
1129 char *err
= strerror (errno
);
1130 char *msg
= alloca (strlen (err
) + 128);
1131 sprintf (msg
, "writing register %d: %s",
1137 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
1141 for (regno
= 0; regno
< the_low_target
.num_regs
; regno
++)
1142 usr_store_inferior_registers (regno
);
1144 #endif /* HAVE_LINUX_USRREGS */
1148 #ifdef HAVE_LINUX_REGSETS
1151 regsets_fetch_inferior_registers ()
1153 struct regset_info
*regset
;
1155 regset
= target_regsets
;
1157 while (regset
->size
>= 0)
1162 if (regset
->size
== 0)
1168 buf
= malloc (regset
->size
);
1169 res
= ptrace (regset
->get_request
, inferior_pid
, 0, buf
);
1174 /* If we get EIO on the first regset, do not try regsets again.
1175 If we get EIO on a later regset, disable that regset. */
1176 if (regset
== target_regsets
)
1190 sprintf (s
, "ptrace(regsets_fetch_inferior_registers) PID=%d",
1195 regset
->store_function (buf
);
1202 regsets_store_inferior_registers ()
1204 struct regset_info
*regset
;
1206 regset
= target_regsets
;
1208 while (regset
->size
>= 0)
1213 if (regset
->size
== 0)
1219 buf
= malloc (regset
->size
);
1220 regset
->fill_function (buf
);
1221 res
= ptrace (regset
->set_request
, inferior_pid
, 0, buf
);
1226 /* If we get EIO on the first regset, do not try regsets again.
1227 If we get EIO on a later regset, disable that regset. */
1228 if (regset
== target_regsets
)
1241 perror ("Warning: ptrace(regsets_store_inferior_registers)");
1250 #endif /* HAVE_LINUX_REGSETS */
1254 linux_fetch_registers (int regno
)
1256 #ifdef HAVE_LINUX_REGSETS
1259 if (regsets_fetch_inferior_registers () == 0)
1263 #ifdef HAVE_LINUX_USRREGS
1264 usr_fetch_inferior_registers (regno
);
1269 linux_store_registers (int regno
)
1271 #ifdef HAVE_LINUX_REGSETS
1274 if (regsets_store_inferior_registers () == 0)
1278 #ifdef HAVE_LINUX_USRREGS
1279 usr_store_inferior_registers (regno
);
1284 /* Copy LEN bytes from inferior's memory starting at MEMADDR
1285 to debugger memory starting at MYADDR. */
1288 linux_read_memory (CORE_ADDR memaddr
, char *myaddr
, int len
)
1291 /* Round starting address down to longword boundary. */
1292 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
1293 /* Round ending address up; get number of longwords that makes. */
1295 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
1296 / sizeof (PTRACE_XFER_TYPE
);
1297 /* Allocate buffer of that many longwords. */
1298 register PTRACE_XFER_TYPE
*buffer
1299 = (PTRACE_XFER_TYPE
*) alloca (count
* sizeof (PTRACE_XFER_TYPE
));
1301 /* Read all the longwords */
1302 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
1305 buffer
[i
] = ptrace (PTRACE_PEEKTEXT
, inferior_pid
, (PTRACE_ARG3_TYPE
) addr
, 0);
1310 /* Copy appropriate bytes out of the buffer. */
1311 memcpy (myaddr
, (char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)), len
);
1316 /* Copy LEN bytes of data from debugger memory at MYADDR
1317 to inferior's memory at MEMADDR.
1318 On failure (cannot write the inferior)
1319 returns the value of errno. */
1322 linux_write_memory (CORE_ADDR memaddr
, const char *myaddr
, int len
)
1325 /* Round starting address down to longword boundary. */
1326 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
1327 /* Round ending address up; get number of longwords that makes. */
1329 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1) / sizeof (PTRACE_XFER_TYPE
);
1330 /* Allocate buffer of that many longwords. */
1331 register PTRACE_XFER_TYPE
*buffer
= (PTRACE_XFER_TYPE
*) alloca (count
* sizeof (PTRACE_XFER_TYPE
));
1336 fprintf (stderr
, "Writing %02x to %08lx\n", (unsigned)myaddr
[0], (long)memaddr
);
1339 /* Fill start and end extra bytes of buffer with existing memory data. */
1341 buffer
[0] = ptrace (PTRACE_PEEKTEXT
, inferior_pid
,
1342 (PTRACE_ARG3_TYPE
) addr
, 0);
1347 = ptrace (PTRACE_PEEKTEXT
, inferior_pid
,
1348 (PTRACE_ARG3_TYPE
) (addr
+ (count
- 1)
1349 * sizeof (PTRACE_XFER_TYPE
)),
1353 /* Copy data to be written over corresponding part of buffer */
1355 memcpy ((char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)), myaddr
, len
);
1357 /* Write the entire buffer. */
1359 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
1362 ptrace (PTRACE_POKETEXT
, inferior_pid
, (PTRACE_ARG3_TYPE
) addr
, buffer
[i
]);
1371 linux_look_up_symbols (void)
1373 #ifdef USE_THREAD_DB
1377 using_threads
= thread_db_init ();
1382 linux_send_signal (int signum
)
1384 extern int signal_pid
;
1386 if (cont_thread
> 0)
1388 struct process_info
*process
;
1390 process
= get_thread_process (current_inferior
);
1391 kill (process
->lwpid
, signum
);
1394 kill (signal_pid
, signum
);
1397 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
1398 to debugger memory starting at MYADDR. */
1401 linux_read_auxv (CORE_ADDR offset
, char *myaddr
, unsigned int len
)
1403 char filename
[PATH_MAX
];
1406 snprintf (filename
, sizeof filename
, "/proc/%d/auxv", inferior_pid
);
1408 fd
= open (filename
, O_RDONLY
);
1412 if (offset
!= (CORE_ADDR
) 0
1413 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
1416 n
= read (fd
, myaddr
, len
);
1424 static struct target_ops linux_target_ops
= {
1425 linux_create_inferior
,
1432 linux_fetch_registers
,
1433 linux_store_registers
,
1436 linux_look_up_symbols
,
1442 linux_init_signals ()
1444 /* FIXME drow/2002-06-09: As above, we should check with LinuxThreads
1445 to find what the cancel signal actually is. */
1446 signal (__SIGRTMIN
+1, SIG_IGN
);
1450 initialize_low (void)
1453 set_target_ops (&linux_target_ops
);
1454 set_breakpoint_data (the_low_target
.breakpoint
,
1455 the_low_target
.breakpoint_len
);
1457 linux_init_signals ();