1 /* Low level interface to ptrace, for the remote server for GDB.
2 Copyright (C) 1995-2015 Free Software Foundation, Inc.
4 This file is part of GDB.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>. */
20 #include "linux-low.h"
21 #include "nat/linux-osdata.h"
26 #include "nat/linux-nat.h"
27 #include "nat/linux-waitpid.h"
29 #include "nat/gdb_ptrace.h"
30 #include "nat/linux-ptrace.h"
31 #include "nat/linux-procfs.h"
32 #include "nat/linux-personality.h"
34 #include <sys/ioctl.h>
37 #include <sys/syscall.h>
41 #include <sys/types.h>
46 #include "filestuff.h"
47 #include "tracepoint.h"
50 /* Don't include <linux/elf.h> here. If it got included by gdb_proc_service.h
51 then ELFMAG0 will have been defined. If it didn't get included by
52 gdb_proc_service.h then including it will likely introduce a duplicate
53 definition of elf_fpregset_t. */
56 #include "nat/linux-namespaces.h"
59 #define SPUFS_MAGIC 0x23c9b64e
62 #ifdef HAVE_PERSONALITY
63 # include <sys/personality.h>
64 # if !HAVE_DECL_ADDR_NO_RANDOMIZE
65 # define ADDR_NO_RANDOMIZE 0x0040000
73 /* Some targets did not define these ptrace constants from the start,
74 so gdbserver defines them locally here. In the future, these may
75 be removed after they are added to asm/ptrace.h. */
76 #if !(defined(PT_TEXT_ADDR) \
77 || defined(PT_DATA_ADDR) \
78 || defined(PT_TEXT_END_ADDR))
79 #if defined(__mcoldfire__)
80 /* These are still undefined in 3.10 kernels. */
81 #define PT_TEXT_ADDR 49*4
82 #define PT_DATA_ADDR 50*4
83 #define PT_TEXT_END_ADDR 51*4
84 /* BFIN already defines these since at least 2.6.32 kernels. */
86 #define PT_TEXT_ADDR 220
87 #define PT_TEXT_END_ADDR 224
88 #define PT_DATA_ADDR 228
89 /* These are still undefined in 3.10 kernels. */
90 #elif defined(__TMS320C6X__)
91 #define PT_TEXT_ADDR (0x10000*4)
92 #define PT_DATA_ADDR (0x10004*4)
93 #define PT_TEXT_END_ADDR (0x10008*4)
97 #ifdef HAVE_LINUX_BTRACE
98 # include "nat/linux-btrace.h"
99 # include "btrace-common.h"
102 #ifndef HAVE_ELF32_AUXV_T
103 /* Copied from glibc's elf.h. */
106 uint32_t a_type
; /* Entry type */
109 uint32_t a_val
; /* Integer value */
110 /* We use to have pointer elements added here. We cannot do that,
111 though, since it does not work when using 32-bit definitions
112 on 64-bit platforms and vice versa. */
117 #ifndef HAVE_ELF64_AUXV_T
118 /* Copied from glibc's elf.h. */
121 uint64_t a_type
; /* Entry type */
124 uint64_t a_val
; /* Integer value */
125 /* We use to have pointer elements added here. We cannot do that,
126 though, since it does not work when using 32-bit definitions
127 on 64-bit platforms and vice versa. */
132 /* Does the current host support PTRACE_GETREGSET? */
133 int have_ptrace_getregset
= -1;
137 /* See nat/linux-nat.h. */
140 ptid_of_lwp (struct lwp_info
*lwp
)
142 return ptid_of (get_lwp_thread (lwp
));
145 /* See nat/linux-nat.h. */
148 lwp_set_arch_private_info (struct lwp_info
*lwp
,
149 struct arch_lwp_info
*info
)
151 lwp
->arch_private
= info
;
154 /* See nat/linux-nat.h. */
156 struct arch_lwp_info
*
157 lwp_arch_private_info (struct lwp_info
*lwp
)
159 return lwp
->arch_private
;
162 /* See nat/linux-nat.h. */
165 lwp_is_stopped (struct lwp_info
*lwp
)
170 /* See nat/linux-nat.h. */
172 enum target_stop_reason
173 lwp_stop_reason (struct lwp_info
*lwp
)
175 return lwp
->stop_reason
;
178 /* A list of all unknown processes which receive stop signals. Some
179 other process will presumably claim each of these as forked
180 children momentarily. */
182 struct simple_pid_list
184 /* The process ID. */
187 /* The status as reported by waitpid. */
191 struct simple_pid_list
*next
;
193 struct simple_pid_list
*stopped_pids
;
195 /* Trivial list manipulation functions to keep track of a list of new
196 stopped processes. */
199 add_to_pid_list (struct simple_pid_list
**listp
, int pid
, int status
)
201 struct simple_pid_list
*new_pid
= XNEW (struct simple_pid_list
);
204 new_pid
->status
= status
;
205 new_pid
->next
= *listp
;
210 pull_pid_from_list (struct simple_pid_list
**listp
, int pid
, int *statusp
)
212 struct simple_pid_list
**p
;
214 for (p
= listp
; *p
!= NULL
; p
= &(*p
)->next
)
215 if ((*p
)->pid
== pid
)
217 struct simple_pid_list
*next
= (*p
)->next
;
219 *statusp
= (*p
)->status
;
227 enum stopping_threads_kind
229 /* Not stopping threads presently. */
230 NOT_STOPPING_THREADS
,
232 /* Stopping threads. */
235 /* Stopping and suspending threads. */
236 STOPPING_AND_SUSPENDING_THREADS
239 /* This is set while stop_all_lwps is in effect. */
240 enum stopping_threads_kind stopping_threads
= NOT_STOPPING_THREADS
;
242 /* FIXME make into a target method? */
243 int using_threads
= 1;
245 /* True if we're presently stabilizing threads (moving them out of
247 static int stabilizing_threads
;
249 static void linux_resume_one_lwp (struct lwp_info
*lwp
,
250 int step
, int signal
, siginfo_t
*info
);
251 static void linux_resume (struct thread_resume
*resume_info
, size_t n
);
252 static void stop_all_lwps (int suspend
, struct lwp_info
*except
);
253 static void unstop_all_lwps (int unsuspend
, struct lwp_info
*except
);
254 static int linux_wait_for_event_filtered (ptid_t wait_ptid
, ptid_t filter_ptid
,
255 int *wstat
, int options
);
256 static int linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
);
257 static struct lwp_info
*add_lwp (ptid_t ptid
);
258 static void linux_mourn (struct process_info
*process
);
259 static int linux_stopped_by_watchpoint (void);
260 static void mark_lwp_dead (struct lwp_info
*lwp
, int wstat
);
261 static int lwp_is_marked_dead (struct lwp_info
*lwp
);
262 static void proceed_all_lwps (void);
263 static int finish_step_over (struct lwp_info
*lwp
);
264 static int kill_lwp (unsigned long lwpid
, int signo
);
265 static void enqueue_pending_signal (struct lwp_info
*lwp
, int signal
, siginfo_t
*info
);
266 static void complete_ongoing_step_over (void);
268 /* When the event-loop is doing a step-over, this points at the thread
270 ptid_t step_over_bkpt
;
272 /* True if the low target can hardware single-step. Such targets
273 don't need a BREAKPOINT_REINSERT_ADDR callback. */
276 can_hardware_single_step (void)
278 return (the_low_target
.breakpoint_reinsert_addr
== NULL
);
281 /* True if the low target supports memory breakpoints. If so, we'll
282 have a GET_PC implementation. */
285 supports_breakpoints (void)
287 return (the_low_target
.get_pc
!= NULL
);
290 /* Returns true if this target can support fast tracepoints. This
291 does not mean that the in-process agent has been loaded in the
295 supports_fast_tracepoints (void)
297 return the_low_target
.install_fast_tracepoint_jump_pad
!= NULL
;
300 /* True if LWP is stopped in its stepping range. */
303 lwp_in_step_range (struct lwp_info
*lwp
)
305 CORE_ADDR pc
= lwp
->stop_pc
;
307 return (pc
>= lwp
->step_range_start
&& pc
< lwp
->step_range_end
);
310 struct pending_signals
314 struct pending_signals
*prev
;
317 /* The read/write ends of the pipe registered as waitable file in the
319 static int linux_event_pipe
[2] = { -1, -1 };
321 /* True if we're currently in async mode. */
322 #define target_is_async_p() (linux_event_pipe[0] != -1)
324 static void send_sigstop (struct lwp_info
*lwp
);
325 static void wait_for_sigstop (void);
327 /* Return non-zero if HEADER is a 64-bit ELF file. */
330 elf_64_header_p (const Elf64_Ehdr
*header
, unsigned int *machine
)
332 if (header
->e_ident
[EI_MAG0
] == ELFMAG0
333 && header
->e_ident
[EI_MAG1
] == ELFMAG1
334 && header
->e_ident
[EI_MAG2
] == ELFMAG2
335 && header
->e_ident
[EI_MAG3
] == ELFMAG3
)
337 *machine
= header
->e_machine
;
338 return header
->e_ident
[EI_CLASS
] == ELFCLASS64
;
345 /* Return non-zero if FILE is a 64-bit ELF file,
346 zero if the file is not a 64-bit ELF file,
347 and -1 if the file is not accessible or doesn't exist. */
350 elf_64_file_p (const char *file
, unsigned int *machine
)
355 fd
= open (file
, O_RDONLY
);
359 if (read (fd
, &header
, sizeof (header
)) != sizeof (header
))
366 return elf_64_header_p (&header
, machine
);
369 /* Accepts an integer PID; Returns true if the executable PID is
370 running is a 64-bit ELF file.. */
373 linux_pid_exe_is_elf_64_file (int pid
, unsigned int *machine
)
377 sprintf (file
, "/proc/%d/exe", pid
);
378 return elf_64_file_p (file
, machine
);
382 delete_lwp (struct lwp_info
*lwp
)
384 struct thread_info
*thr
= get_lwp_thread (lwp
);
387 debug_printf ("deleting %ld\n", lwpid_of (thr
));
390 free (lwp
->arch_private
);
394 /* Add a process to the common process list, and set its private
397 static struct process_info
*
398 linux_add_process (int pid
, int attached
)
400 struct process_info
*proc
;
402 proc
= add_process (pid
, attached
);
403 proc
->priv
= XCNEW (struct process_info_private
);
405 if (the_low_target
.new_process
!= NULL
)
406 proc
->priv
->arch_private
= the_low_target
.new_process ();
411 static CORE_ADDR
get_pc (struct lwp_info
*lwp
);
413 /* Implement the arch_setup target_ops method. */
416 linux_arch_setup (void)
418 the_low_target
.arch_setup ();
421 /* Call the target arch_setup function on THREAD. */
424 linux_arch_setup_thread (struct thread_info
*thread
)
426 struct thread_info
*saved_thread
;
428 saved_thread
= current_thread
;
429 current_thread
= thread
;
433 current_thread
= saved_thread
;
436 /* Handle a GNU/Linux extended wait response. If we see a clone,
437 fork, or vfork event, we need to add the new LWP to our list
438 (and return 0 so as not to report the trap to higher layers).
439 If we see an exec event, we will modify ORIG_EVENT_LWP to point
440 to a new LWP representing the new program. */
443 handle_extended_wait (struct lwp_info
**orig_event_lwp
, int wstat
)
445 struct lwp_info
*event_lwp
= *orig_event_lwp
;
446 int event
= linux_ptrace_get_extended_event (wstat
);
447 struct thread_info
*event_thr
= get_lwp_thread (event_lwp
);
448 struct lwp_info
*new_lwp
;
450 gdb_assert (event_lwp
->waitstatus
.kind
== TARGET_WAITKIND_IGNORE
);
452 if ((event
== PTRACE_EVENT_FORK
) || (event
== PTRACE_EVENT_VFORK
)
453 || (event
== PTRACE_EVENT_CLONE
))
456 unsigned long new_pid
;
459 /* Get the pid of the new lwp. */
460 ptrace (PTRACE_GETEVENTMSG
, lwpid_of (event_thr
), (PTRACE_TYPE_ARG3
) 0,
463 /* If we haven't already seen the new PID stop, wait for it now. */
464 if (!pull_pid_from_list (&stopped_pids
, new_pid
, &status
))
466 /* The new child has a pending SIGSTOP. We can't affect it until it
467 hits the SIGSTOP, but we're already attached. */
469 ret
= my_waitpid (new_pid
, &status
, __WALL
);
472 perror_with_name ("waiting for new child");
473 else if (ret
!= new_pid
)
474 warning ("wait returned unexpected PID %d", ret
);
475 else if (!WIFSTOPPED (status
))
476 warning ("wait returned unexpected status 0x%x", status
);
479 if (event
== PTRACE_EVENT_FORK
|| event
== PTRACE_EVENT_VFORK
)
481 struct process_info
*parent_proc
;
482 struct process_info
*child_proc
;
483 struct lwp_info
*child_lwp
;
484 struct thread_info
*child_thr
;
485 struct target_desc
*tdesc
;
487 ptid
= ptid_build (new_pid
, new_pid
, 0);
491 debug_printf ("HEW: Got fork event from LWP %ld, "
493 ptid_get_lwp (ptid_of (event_thr
)),
494 ptid_get_pid (ptid
));
497 /* Add the new process to the tables and clone the breakpoint
498 lists of the parent. We need to do this even if the new process
499 will be detached, since we will need the process object and the
500 breakpoints to remove any breakpoints from memory when we
501 detach, and the client side will access registers. */
502 child_proc
= linux_add_process (new_pid
, 0);
503 gdb_assert (child_proc
!= NULL
);
504 child_lwp
= add_lwp (ptid
);
505 gdb_assert (child_lwp
!= NULL
);
506 child_lwp
->stopped
= 1;
507 child_lwp
->must_set_ptrace_flags
= 1;
508 child_lwp
->status_pending_p
= 0;
509 child_thr
= get_lwp_thread (child_lwp
);
510 child_thr
->last_resume_kind
= resume_stop
;
511 child_thr
->last_status
.kind
= TARGET_WAITKIND_STOPPED
;
513 /* If we're suspending all threads, leave this one suspended
515 if (stopping_threads
== STOPPING_AND_SUSPENDING_THREADS
)
518 debug_printf ("HEW: leaving child suspended\n");
519 child_lwp
->suspended
= 1;
522 parent_proc
= get_thread_process (event_thr
);
523 child_proc
->attached
= parent_proc
->attached
;
524 clone_all_breakpoints (&child_proc
->breakpoints
,
525 &child_proc
->raw_breakpoints
,
526 parent_proc
->breakpoints
);
528 tdesc
= XNEW (struct target_desc
);
529 copy_target_description (tdesc
, parent_proc
->tdesc
);
530 child_proc
->tdesc
= tdesc
;
532 /* Clone arch-specific process data. */
533 if (the_low_target
.new_fork
!= NULL
)
534 the_low_target
.new_fork (parent_proc
, child_proc
);
536 /* Save fork info in the parent thread. */
537 if (event
== PTRACE_EVENT_FORK
)
538 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_FORKED
;
539 else if (event
== PTRACE_EVENT_VFORK
)
540 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_VFORKED
;
542 event_lwp
->waitstatus
.value
.related_pid
= ptid
;
544 /* The status_pending field contains bits denoting the
545 extended event, so when the pending event is handled,
546 the handler will look at lwp->waitstatus. */
547 event_lwp
->status_pending_p
= 1;
548 event_lwp
->status_pending
= wstat
;
550 /* Report the event. */
555 debug_printf ("HEW: Got clone event "
556 "from LWP %ld, new child is LWP %ld\n",
557 lwpid_of (event_thr
), new_pid
);
559 ptid
= ptid_build (pid_of (event_thr
), new_pid
, 0);
560 new_lwp
= add_lwp (ptid
);
562 /* Either we're going to immediately resume the new thread
563 or leave it stopped. linux_resume_one_lwp is a nop if it
564 thinks the thread is currently running, so set this first
565 before calling linux_resume_one_lwp. */
566 new_lwp
->stopped
= 1;
568 /* If we're suspending all threads, leave this one suspended
570 if (stopping_threads
== STOPPING_AND_SUSPENDING_THREADS
)
571 new_lwp
->suspended
= 1;
573 /* Normally we will get the pending SIGSTOP. But in some cases
574 we might get another signal delivered to the group first.
575 If we do get another signal, be sure not to lose it. */
576 if (WSTOPSIG (status
) != SIGSTOP
)
578 new_lwp
->stop_expected
= 1;
579 new_lwp
->status_pending_p
= 1;
580 new_lwp
->status_pending
= status
;
582 else if (report_thread_events
)
584 new_lwp
->waitstatus
.kind
= TARGET_WAITKIND_THREAD_CREATED
;
585 new_lwp
->status_pending_p
= 1;
586 new_lwp
->status_pending
= status
;
589 /* Don't report the event. */
592 else if (event
== PTRACE_EVENT_VFORK_DONE
)
594 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_VFORK_DONE
;
596 /* Report the event. */
599 else if (event
== PTRACE_EVENT_EXEC
&& report_exec_events
)
601 struct process_info
*proc
;
607 debug_printf ("HEW: Got exec event from LWP %ld\n",
608 lwpid_of (event_thr
));
611 /* Get the event ptid. */
612 event_ptid
= ptid_of (event_thr
);
613 event_pid
= ptid_get_pid (event_ptid
);
615 /* Delete the execing process and all its threads. */
616 proc
= get_thread_process (event_thr
);
618 current_thread
= NULL
;
620 /* Create a new process/lwp/thread. */
621 proc
= linux_add_process (event_pid
, 0);
622 event_lwp
= add_lwp (event_ptid
);
623 event_thr
= get_lwp_thread (event_lwp
);
624 gdb_assert (current_thread
== event_thr
);
625 linux_arch_setup_thread (event_thr
);
627 /* Set the event status. */
628 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_EXECD
;
629 event_lwp
->waitstatus
.value
.execd_pathname
630 = xstrdup (linux_proc_pid_to_exec_file (lwpid_of (event_thr
)));
632 /* Mark the exec status as pending. */
633 event_lwp
->stopped
= 1;
634 event_lwp
->status_pending_p
= 1;
635 event_lwp
->status_pending
= wstat
;
636 event_thr
->last_resume_kind
= resume_continue
;
637 event_thr
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
639 /* Report the event. */
640 *orig_event_lwp
= event_lwp
;
644 internal_error (__FILE__
, __LINE__
, _("unknown ptrace event %d"), event
);
647 /* Return the PC as read from the regcache of LWP, without any
651 get_pc (struct lwp_info
*lwp
)
653 struct thread_info
*saved_thread
;
654 struct regcache
*regcache
;
657 if (the_low_target
.get_pc
== NULL
)
660 saved_thread
= current_thread
;
661 current_thread
= get_lwp_thread (lwp
);
663 regcache
= get_thread_regcache (current_thread
, 1);
664 pc
= (*the_low_target
.get_pc
) (regcache
);
667 debug_printf ("pc is 0x%lx\n", (long) pc
);
669 current_thread
= saved_thread
;
673 /* This function should only be called if LWP got a SIGTRAP.
674 The SIGTRAP could mean several things.
676 On i386, where decr_pc_after_break is non-zero:
678 If we were single-stepping this process using PTRACE_SINGLESTEP, we
679 will get only the one SIGTRAP. The value of $eip will be the next
680 instruction. If the instruction we stepped over was a breakpoint,
681 we need to decrement the PC.
683 If we continue the process using PTRACE_CONT, we will get a
684 SIGTRAP when we hit a breakpoint. The value of $eip will be
685 the instruction after the breakpoint (i.e. needs to be
686 decremented). If we report the SIGTRAP to GDB, we must also
687 report the undecremented PC. If the breakpoint is removed, we
688 must resume at the decremented PC.
690 On a non-decr_pc_after_break machine with hardware or kernel
693 If we either single-step a breakpoint instruction, or continue and
694 hit a breakpoint instruction, our PC will point at the breakpoint
698 check_stopped_by_breakpoint (struct lwp_info
*lwp
)
701 CORE_ADDR sw_breakpoint_pc
;
702 struct thread_info
*saved_thread
;
703 #if USE_SIGTRAP_SIGINFO
707 if (the_low_target
.get_pc
== NULL
)
711 sw_breakpoint_pc
= pc
- the_low_target
.decr_pc_after_break
;
713 /* breakpoint_at reads from the current thread. */
714 saved_thread
= current_thread
;
715 current_thread
= get_lwp_thread (lwp
);
717 #if USE_SIGTRAP_SIGINFO
718 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
719 (PTRACE_TYPE_ARG3
) 0, &siginfo
) == 0)
721 if (siginfo
.si_signo
== SIGTRAP
)
723 if (GDB_ARCH_IS_TRAP_BRKPT (siginfo
.si_code
))
727 struct thread_info
*thr
= get_lwp_thread (lwp
);
729 debug_printf ("CSBB: %s stopped by software breakpoint\n",
730 target_pid_to_str (ptid_of (thr
)));
733 /* Back up the PC if necessary. */
734 if (pc
!= sw_breakpoint_pc
)
736 struct regcache
*regcache
737 = get_thread_regcache (current_thread
, 1);
738 (*the_low_target
.set_pc
) (regcache
, sw_breakpoint_pc
);
741 lwp
->stop_pc
= sw_breakpoint_pc
;
742 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
743 current_thread
= saved_thread
;
746 else if (siginfo
.si_code
== TRAP_HWBKPT
)
750 struct thread_info
*thr
= get_lwp_thread (lwp
);
752 debug_printf ("CSBB: %s stopped by hardware "
753 "breakpoint/watchpoint\n",
754 target_pid_to_str (ptid_of (thr
)));
758 lwp
->stop_reason
= TARGET_STOPPED_BY_HW_BREAKPOINT
;
759 current_thread
= saved_thread
;
762 else if (siginfo
.si_code
== TRAP_TRACE
)
766 struct thread_info
*thr
= get_lwp_thread (lwp
);
768 debug_printf ("CSBB: %s stopped by trace\n",
769 target_pid_to_str (ptid_of (thr
)));
772 lwp
->stop_reason
= TARGET_STOPPED_BY_SINGLE_STEP
;
777 /* We may have just stepped a breakpoint instruction. E.g., in
778 non-stop mode, GDB first tells the thread A to step a range, and
779 then the user inserts a breakpoint inside the range. In that
780 case we need to report the breakpoint PC. */
781 if ((!lwp
->stepping
|| lwp
->stop_pc
== sw_breakpoint_pc
)
782 && (*the_low_target
.breakpoint_at
) (sw_breakpoint_pc
))
786 struct thread_info
*thr
= get_lwp_thread (lwp
);
788 debug_printf ("CSBB: %s stopped by software breakpoint\n",
789 target_pid_to_str (ptid_of (thr
)));
792 /* Back up the PC if necessary. */
793 if (pc
!= sw_breakpoint_pc
)
795 struct regcache
*regcache
796 = get_thread_regcache (current_thread
, 1);
797 (*the_low_target
.set_pc
) (regcache
, sw_breakpoint_pc
);
800 lwp
->stop_pc
= sw_breakpoint_pc
;
801 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
802 current_thread
= saved_thread
;
806 if (hardware_breakpoint_inserted_here (pc
))
810 struct thread_info
*thr
= get_lwp_thread (lwp
);
812 debug_printf ("CSBB: %s stopped by hardware breakpoint\n",
813 target_pid_to_str (ptid_of (thr
)));
817 lwp
->stop_reason
= TARGET_STOPPED_BY_HW_BREAKPOINT
;
818 current_thread
= saved_thread
;
823 current_thread
= saved_thread
;
827 static struct lwp_info
*
828 add_lwp (ptid_t ptid
)
830 struct lwp_info
*lwp
;
832 lwp
= XCNEW (struct lwp_info
);
834 lwp
->waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
836 if (the_low_target
.new_thread
!= NULL
)
837 the_low_target
.new_thread (lwp
);
839 lwp
->thread
= add_thread (ptid
, lwp
);
844 /* Start an inferior process and returns its pid.
845 ALLARGS is a vector of program-name and args. */
848 linux_create_inferior (char *program
, char **allargs
)
850 struct lwp_info
*new_lwp
;
853 struct cleanup
*restore_personality
854 = maybe_disable_address_space_randomization (disable_randomization
);
856 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
862 perror_with_name ("fork");
867 ptrace (PTRACE_TRACEME
, 0, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
869 #ifndef __ANDROID__ /* Bionic doesn't use SIGRTMIN the way glibc does. */
870 signal (__SIGRTMIN
+ 1, SIG_DFL
);
875 /* If gdbserver is connected to gdb via stdio, redirect the inferior's
876 stdout to stderr so that inferior i/o doesn't corrupt the connection.
877 Also, redirect stdin to /dev/null. */
878 if (remote_connection_is_stdio ())
881 open ("/dev/null", O_RDONLY
);
883 if (write (2, "stdin/stdout redirected\n",
884 sizeof ("stdin/stdout redirected\n") - 1) < 0)
886 /* Errors ignored. */;
890 execv (program
, allargs
);
892 execvp (program
, allargs
);
894 fprintf (stderr
, "Cannot exec %s: %s.\n", program
,
900 do_cleanups (restore_personality
);
902 linux_add_process (pid
, 0);
904 ptid
= ptid_build (pid
, pid
, 0);
905 new_lwp
= add_lwp (ptid
);
906 new_lwp
->must_set_ptrace_flags
= 1;
911 /* Attach to an inferior process. Returns 0 on success, ERRNO on
915 linux_attach_lwp (ptid_t ptid
)
917 struct lwp_info
*new_lwp
;
918 int lwpid
= ptid_get_lwp (ptid
);
920 if (ptrace (PTRACE_ATTACH
, lwpid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0)
924 new_lwp
= add_lwp (ptid
);
926 /* We need to wait for SIGSTOP before being able to make the next
927 ptrace call on this LWP. */
928 new_lwp
->must_set_ptrace_flags
= 1;
930 if (linux_proc_pid_is_stopped (lwpid
))
933 debug_printf ("Attached to a stopped process\n");
935 /* The process is definitely stopped. It is in a job control
936 stop, unless the kernel predates the TASK_STOPPED /
937 TASK_TRACED distinction, in which case it might be in a
938 ptrace stop. Make sure it is in a ptrace stop; from there we
939 can kill it, signal it, et cetera.
941 First make sure there is a pending SIGSTOP. Since we are
942 already attached, the process can not transition from stopped
943 to running without a PTRACE_CONT; so we know this signal will
944 go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
945 probably already in the queue (unless this kernel is old
946 enough to use TASK_STOPPED for ptrace stops); but since
947 SIGSTOP is not an RT signal, it can only be queued once. */
948 kill_lwp (lwpid
, SIGSTOP
);
950 /* Finally, resume the stopped process. This will deliver the
951 SIGSTOP (or a higher priority signal, just like normal
952 PTRACE_ATTACH), which we'll catch later on. */
953 ptrace (PTRACE_CONT
, lwpid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
956 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
959 There are several cases to consider here:
961 1) gdbserver has already attached to the process and is being notified
962 of a new thread that is being created.
963 In this case we should ignore that SIGSTOP and resume the
964 process. This is handled below by setting stop_expected = 1,
965 and the fact that add_thread sets last_resume_kind ==
968 2) This is the first thread (the process thread), and we're attaching
969 to it via attach_inferior.
970 In this case we want the process thread to stop.
971 This is handled by having linux_attach set last_resume_kind ==
972 resume_stop after we return.
974 If the pid we are attaching to is also the tgid, we attach to and
975 stop all the existing threads. Otherwise, we attach to pid and
976 ignore any other threads in the same group as this pid.
978 3) GDB is connecting to gdbserver and is requesting an enumeration of all
980 In this case we want the thread to stop.
981 FIXME: This case is currently not properly handled.
982 We should wait for the SIGSTOP but don't. Things work apparently
983 because enough time passes between when we ptrace (ATTACH) and when
984 gdb makes the next ptrace call on the thread.
986 On the other hand, if we are currently trying to stop all threads, we
987 should treat the new thread as if we had sent it a SIGSTOP. This works
988 because we are guaranteed that the add_lwp call above added us to the
989 end of the list, and so the new thread has not yet reached
990 wait_for_sigstop (but will). */
991 new_lwp
->stop_expected
= 1;
996 /* Callback for linux_proc_attach_tgid_threads. Attach to PTID if not
997 already attached. Returns true if a new LWP is found, false
1001 attach_proc_task_lwp_callback (ptid_t ptid
)
1003 /* Is this a new thread? */
1004 if (find_thread_ptid (ptid
) == NULL
)
1006 int lwpid
= ptid_get_lwp (ptid
);
1010 debug_printf ("Found new lwp %d\n", lwpid
);
1012 err
= linux_attach_lwp (ptid
);
1014 /* Be quiet if we simply raced with the thread exiting. EPERM
1015 is returned if the thread's task still exists, and is marked
1016 as exited or zombie, as well as other conditions, so in that
1017 case, confirm the status in /proc/PID/status. */
1019 || (err
== EPERM
&& linux_proc_pid_is_gone (lwpid
)))
1023 debug_printf ("Cannot attach to lwp %d: "
1024 "thread is gone (%d: %s)\n",
1025 lwpid
, err
, strerror (err
));
1030 warning (_("Cannot attach to lwp %d: %s"),
1032 linux_ptrace_attach_fail_reason_string (ptid
, err
));
1040 static void async_file_mark (void);
1042 /* Attach to PID. If PID is the tgid, attach to it and all
1046 linux_attach (unsigned long pid
)
1048 struct process_info
*proc
;
1049 struct thread_info
*initial_thread
;
1050 ptid_t ptid
= ptid_build (pid
, pid
, 0);
1053 /* Attach to PID. We will check for other threads
1055 err
= linux_attach_lwp (ptid
);
1057 error ("Cannot attach to process %ld: %s",
1058 pid
, linux_ptrace_attach_fail_reason_string (ptid
, err
));
1060 proc
= linux_add_process (pid
, 1);
1062 /* Don't ignore the initial SIGSTOP if we just attached to this
1063 process. It will be collected by wait shortly. */
1064 initial_thread
= find_thread_ptid (ptid_build (pid
, pid
, 0));
1065 initial_thread
->last_resume_kind
= resume_stop
;
1067 /* We must attach to every LWP. If /proc is mounted, use that to
1068 find them now. On the one hand, the inferior may be using raw
1069 clone instead of using pthreads. On the other hand, even if it
1070 is using pthreads, GDB may not be connected yet (thread_db needs
1071 to do symbol lookups, through qSymbol). Also, thread_db walks
1072 structures in the inferior's address space to find the list of
1073 threads/LWPs, and those structures may well be corrupted. Note
1074 that once thread_db is loaded, we'll still use it to list threads
1075 and associate pthread info with each LWP. */
1076 linux_proc_attach_tgid_threads (pid
, attach_proc_task_lwp_callback
);
1078 /* GDB will shortly read the xml target description for this
1079 process, to figure out the process' architecture. But the target
1080 description is only filled in when the first process/thread in
1081 the thread group reports its initial PTRACE_ATTACH SIGSTOP. Do
1082 that now, otherwise, if GDB is fast enough, it could read the
1083 target description _before_ that initial stop. */
1086 struct lwp_info
*lwp
;
1088 ptid_t pid_ptid
= pid_to_ptid (pid
);
1090 lwpid
= linux_wait_for_event_filtered (pid_ptid
, pid_ptid
,
1092 gdb_assert (lwpid
> 0);
1094 lwp
= find_lwp_pid (pid_to_ptid (lwpid
));
1096 if (!WIFSTOPPED (wstat
) || WSTOPSIG (wstat
) != SIGSTOP
)
1098 lwp
->status_pending_p
= 1;
1099 lwp
->status_pending
= wstat
;
1102 initial_thread
->last_resume_kind
= resume_continue
;
1106 gdb_assert (proc
->tdesc
!= NULL
);
1119 second_thread_of_pid_p (struct inferior_list_entry
*entry
, void *args
)
1121 struct counter
*counter
= (struct counter
*) args
;
1123 if (ptid_get_pid (entry
->id
) == counter
->pid
)
1125 if (++counter
->count
> 1)
1133 last_thread_of_process_p (int pid
)
1135 struct counter counter
= { pid
, 0 };
1137 return (find_inferior (&all_threads
,
1138 second_thread_of_pid_p
, &counter
) == NULL
);
1144 linux_kill_one_lwp (struct lwp_info
*lwp
)
1146 struct thread_info
*thr
= get_lwp_thread (lwp
);
1147 int pid
= lwpid_of (thr
);
1149 /* PTRACE_KILL is unreliable. After stepping into a signal handler,
1150 there is no signal context, and ptrace(PTRACE_KILL) (or
1151 ptrace(PTRACE_CONT, SIGKILL), pretty much the same) acts like
1152 ptrace(CONT, pid, 0,0) and just resumes the tracee. A better
1153 alternative is to kill with SIGKILL. We only need one SIGKILL
1154 per process, not one for each thread. But since we still support
1155 linuxthreads, and we also support debugging programs using raw
1156 clone without CLONE_THREAD, we send one for each thread. For
1157 years, we used PTRACE_KILL only, so we're being a bit paranoid
1158 about some old kernels where PTRACE_KILL might work better
1159 (dubious if there are any such, but that's why it's paranoia), so
1160 we try SIGKILL first, PTRACE_KILL second, and so we're fine
1164 kill_lwp (pid
, SIGKILL
);
1167 int save_errno
= errno
;
1169 debug_printf ("LKL: kill_lwp (SIGKILL) %s, 0, 0 (%s)\n",
1170 target_pid_to_str (ptid_of (thr
)),
1171 save_errno
? strerror (save_errno
) : "OK");
1175 ptrace (PTRACE_KILL
, pid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
1178 int save_errno
= errno
;
1180 debug_printf ("LKL: PTRACE_KILL %s, 0, 0 (%s)\n",
1181 target_pid_to_str (ptid_of (thr
)),
1182 save_errno
? strerror (save_errno
) : "OK");
1186 /* Kill LWP and wait for it to die. */
1189 kill_wait_lwp (struct lwp_info
*lwp
)
1191 struct thread_info
*thr
= get_lwp_thread (lwp
);
1192 int pid
= ptid_get_pid (ptid_of (thr
));
1193 int lwpid
= ptid_get_lwp (ptid_of (thr
));
1198 debug_printf ("kwl: killing lwp %d, for pid: %d\n", lwpid
, pid
);
1202 linux_kill_one_lwp (lwp
);
1204 /* Make sure it died. Notes:
1206 - The loop is most likely unnecessary.
1208 - We don't use linux_wait_for_event as that could delete lwps
1209 while we're iterating over them. We're not interested in
1210 any pending status at this point, only in making sure all
1211 wait status on the kernel side are collected until the
1214 - We don't use __WALL here as the __WALL emulation relies on
1215 SIGCHLD, and killing a stopped process doesn't generate
1216 one, nor an exit status.
1218 res
= my_waitpid (lwpid
, &wstat
, 0);
1219 if (res
== -1 && errno
== ECHILD
)
1220 res
= my_waitpid (lwpid
, &wstat
, __WCLONE
);
1221 } while (res
> 0 && WIFSTOPPED (wstat
));
1223 /* Even if it was stopped, the child may have already disappeared.
1224 E.g., if it was killed by SIGKILL. */
1225 if (res
< 0 && errno
!= ECHILD
)
1226 perror_with_name ("kill_wait_lwp");
1229 /* Callback for `find_inferior'. Kills an lwp of a given process,
1230 except the leader. */
1233 kill_one_lwp_callback (struct inferior_list_entry
*entry
, void *args
)
1235 struct thread_info
*thread
= (struct thread_info
*) entry
;
1236 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1237 int pid
= * (int *) args
;
1239 if (ptid_get_pid (entry
->id
) != pid
)
1242 /* We avoid killing the first thread here, because of a Linux kernel (at
1243 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
1244 the children get a chance to be reaped, it will remain a zombie
1247 if (lwpid_of (thread
) == pid
)
1250 debug_printf ("lkop: is last of process %s\n",
1251 target_pid_to_str (entry
->id
));
1255 kill_wait_lwp (lwp
);
1260 linux_kill (int pid
)
1262 struct process_info
*process
;
1263 struct lwp_info
*lwp
;
1265 process
= find_process_pid (pid
);
1266 if (process
== NULL
)
1269 /* If we're killing a running inferior, make sure it is stopped
1270 first, as PTRACE_KILL will not work otherwise. */
1271 stop_all_lwps (0, NULL
);
1273 find_inferior (&all_threads
, kill_one_lwp_callback
, &pid
);
1275 /* See the comment in linux_kill_one_lwp. We did not kill the first
1276 thread in the list, so do so now. */
1277 lwp
= find_lwp_pid (pid_to_ptid (pid
));
1282 debug_printf ("lk_1: cannot find lwp for pid: %d\n",
1286 kill_wait_lwp (lwp
);
1288 the_target
->mourn (process
);
1290 /* Since we presently can only stop all lwps of all processes, we
1291 need to unstop lwps of other processes. */
1292 unstop_all_lwps (0, NULL
);
1296 /* Get pending signal of THREAD, for detaching purposes. This is the
1297 signal the thread last stopped for, which we need to deliver to the
1298 thread when detaching, otherwise, it'd be suppressed/lost. */
1301 get_detach_signal (struct thread_info
*thread
)
1303 enum gdb_signal signo
= GDB_SIGNAL_0
;
1305 struct lwp_info
*lp
= get_thread_lwp (thread
);
1307 if (lp
->status_pending_p
)
1308 status
= lp
->status_pending
;
1311 /* If the thread had been suspended by gdbserver, and it stopped
1312 cleanly, then it'll have stopped with SIGSTOP. But we don't
1313 want to deliver that SIGSTOP. */
1314 if (thread
->last_status
.kind
!= TARGET_WAITKIND_STOPPED
1315 || thread
->last_status
.value
.sig
== GDB_SIGNAL_0
)
1318 /* Otherwise, we may need to deliver the signal we
1320 status
= lp
->last_status
;
1323 if (!WIFSTOPPED (status
))
1326 debug_printf ("GPS: lwp %s hasn't stopped: no pending signal\n",
1327 target_pid_to_str (ptid_of (thread
)));
1331 /* Extended wait statuses aren't real SIGTRAPs. */
1332 if (WSTOPSIG (status
) == SIGTRAP
&& linux_is_extended_waitstatus (status
))
1335 debug_printf ("GPS: lwp %s had stopped with extended "
1336 "status: no pending signal\n",
1337 target_pid_to_str (ptid_of (thread
)));
1341 signo
= gdb_signal_from_host (WSTOPSIG (status
));
1343 if (program_signals_p
&& !program_signals
[signo
])
1346 debug_printf ("GPS: lwp %s had signal %s, but it is in nopass state\n",
1347 target_pid_to_str (ptid_of (thread
)),
1348 gdb_signal_to_string (signo
));
1351 else if (!program_signals_p
1352 /* If we have no way to know which signals GDB does not
1353 want to have passed to the program, assume
1354 SIGTRAP/SIGINT, which is GDB's default. */
1355 && (signo
== GDB_SIGNAL_TRAP
|| signo
== GDB_SIGNAL_INT
))
1358 debug_printf ("GPS: lwp %s had signal %s, "
1359 "but we don't know if we should pass it. "
1360 "Default to not.\n",
1361 target_pid_to_str (ptid_of (thread
)),
1362 gdb_signal_to_string (signo
));
1368 debug_printf ("GPS: lwp %s has pending signal %s: delivering it.\n",
1369 target_pid_to_str (ptid_of (thread
)),
1370 gdb_signal_to_string (signo
));
1372 return WSTOPSIG (status
);
1377 linux_detach_one_lwp (struct inferior_list_entry
*entry
, void *args
)
1379 struct thread_info
*thread
= (struct thread_info
*) entry
;
1380 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1381 int pid
= * (int *) args
;
1384 if (ptid_get_pid (entry
->id
) != pid
)
1387 /* If there is a pending SIGSTOP, get rid of it. */
1388 if (lwp
->stop_expected
)
1391 debug_printf ("Sending SIGCONT to %s\n",
1392 target_pid_to_str (ptid_of (thread
)));
1394 kill_lwp (lwpid_of (thread
), SIGCONT
);
1395 lwp
->stop_expected
= 0;
1398 /* Flush any pending changes to the process's registers. */
1399 regcache_invalidate_thread (thread
);
1401 /* Pass on any pending signal for this thread. */
1402 sig
= get_detach_signal (thread
);
1404 /* Finally, let it resume. */
1405 if (the_low_target
.prepare_to_resume
!= NULL
)
1406 the_low_target
.prepare_to_resume (lwp
);
1407 if (ptrace (PTRACE_DETACH
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
1408 (PTRACE_TYPE_ARG4
) (long) sig
) < 0)
1409 error (_("Can't detach %s: %s"),
1410 target_pid_to_str (ptid_of (thread
)),
1418 linux_detach (int pid
)
1420 struct process_info
*process
;
1422 process
= find_process_pid (pid
);
1423 if (process
== NULL
)
1426 /* As there's a step over already in progress, let it finish first,
1427 otherwise nesting a stabilize_threads operation on top gets real
1429 complete_ongoing_step_over ();
1431 /* Stop all threads before detaching. First, ptrace requires that
1432 the thread is stopped to sucessfully detach. Second, thread_db
1433 may need to uninstall thread event breakpoints from memory, which
1434 only works with a stopped process anyway. */
1435 stop_all_lwps (0, NULL
);
1437 #ifdef USE_THREAD_DB
1438 thread_db_detach (process
);
1441 /* Stabilize threads (move out of jump pads). */
1442 stabilize_threads ();
1444 find_inferior (&all_threads
, linux_detach_one_lwp
, &pid
);
1446 the_target
->mourn (process
);
1448 /* Since we presently can only stop all lwps of all processes, we
1449 need to unstop lwps of other processes. */
1450 unstop_all_lwps (0, NULL
);
1454 /* Remove all LWPs that belong to process PROC from the lwp list. */
1457 delete_lwp_callback (struct inferior_list_entry
*entry
, void *proc
)
1459 struct thread_info
*thread
= (struct thread_info
*) entry
;
1460 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1461 struct process_info
*process
= (struct process_info
*) proc
;
1463 if (pid_of (thread
) == pid_of (process
))
1470 linux_mourn (struct process_info
*process
)
1472 struct process_info_private
*priv
;
1474 #ifdef USE_THREAD_DB
1475 thread_db_mourn (process
);
1478 find_inferior (&all_threads
, delete_lwp_callback
, process
);
1480 /* Freeing all private data. */
1481 priv
= process
->priv
;
1482 free (priv
->arch_private
);
1484 process
->priv
= NULL
;
1486 remove_process (process
);
1490 linux_join (int pid
)
1495 ret
= my_waitpid (pid
, &status
, 0);
1496 if (WIFEXITED (status
) || WIFSIGNALED (status
))
1498 } while (ret
!= -1 || errno
!= ECHILD
);
1501 /* Return nonzero if the given thread is still alive. */
1503 linux_thread_alive (ptid_t ptid
)
1505 struct lwp_info
*lwp
= find_lwp_pid (ptid
);
1507 /* We assume we always know if a thread exits. If a whole process
1508 exited but we still haven't been able to report it to GDB, we'll
1509 hold on to the last lwp of the dead process. */
1511 return !lwp_is_marked_dead (lwp
);
1516 /* Return 1 if this lwp still has an interesting status pending. If
1517 not (e.g., it had stopped for a breakpoint that is gone), return
1521 thread_still_has_status_pending_p (struct thread_info
*thread
)
1523 struct lwp_info
*lp
= get_thread_lwp (thread
);
1525 if (!lp
->status_pending_p
)
1528 if (thread
->last_resume_kind
!= resume_stop
1529 && (lp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
1530 || lp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
1532 struct thread_info
*saved_thread
;
1536 gdb_assert (lp
->last_status
!= 0);
1540 saved_thread
= current_thread
;
1541 current_thread
= thread
;
1543 if (pc
!= lp
->stop_pc
)
1546 debug_printf ("PC of %ld changed\n",
1551 #if !USE_SIGTRAP_SIGINFO
1552 else if (lp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
1553 && !(*the_low_target
.breakpoint_at
) (pc
))
1556 debug_printf ("previous SW breakpoint of %ld gone\n",
1560 else if (lp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
1561 && !hardware_breakpoint_inserted_here (pc
))
1564 debug_printf ("previous HW breakpoint of %ld gone\n",
1570 current_thread
= saved_thread
;
1575 debug_printf ("discarding pending breakpoint status\n");
1576 lp
->status_pending_p
= 0;
1584 /* Returns true if LWP is resumed from the client's perspective. */
1587 lwp_resumed (struct lwp_info
*lwp
)
1589 struct thread_info
*thread
= get_lwp_thread (lwp
);
1591 if (thread
->last_resume_kind
!= resume_stop
)
1594 /* Did gdb send us a `vCont;t', but we haven't reported the
1595 corresponding stop to gdb yet? If so, the thread is still
1596 resumed/running from gdb's perspective. */
1597 if (thread
->last_resume_kind
== resume_stop
1598 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
)
1604 /* Return 1 if this lwp has an interesting status pending. */
1606 status_pending_p_callback (struct inferior_list_entry
*entry
, void *arg
)
1608 struct thread_info
*thread
= (struct thread_info
*) entry
;
1609 struct lwp_info
*lp
= get_thread_lwp (thread
);
1610 ptid_t ptid
= * (ptid_t
*) arg
;
1612 /* Check if we're only interested in events from a specific process
1613 or a specific LWP. */
1614 if (!ptid_match (ptid_of (thread
), ptid
))
1617 if (!lwp_resumed (lp
))
1620 if (lp
->status_pending_p
1621 && !thread_still_has_status_pending_p (thread
))
1623 linux_resume_one_lwp (lp
, lp
->stepping
, GDB_SIGNAL_0
, NULL
);
1627 return lp
->status_pending_p
;
1631 same_lwp (struct inferior_list_entry
*entry
, void *data
)
1633 ptid_t ptid
= *(ptid_t
*) data
;
1636 if (ptid_get_lwp (ptid
) != 0)
1637 lwp
= ptid_get_lwp (ptid
);
1639 lwp
= ptid_get_pid (ptid
);
1641 if (ptid_get_lwp (entry
->id
) == lwp
)
1648 find_lwp_pid (ptid_t ptid
)
1650 struct inferior_list_entry
*thread
1651 = find_inferior (&all_threads
, same_lwp
, &ptid
);
1656 return get_thread_lwp ((struct thread_info
*) thread
);
1659 /* Return the number of known LWPs in the tgid given by PID. */
1664 struct inferior_list_entry
*inf
, *tmp
;
1667 ALL_INFERIORS (&all_threads
, inf
, tmp
)
1669 if (ptid_get_pid (inf
->id
) == pid
)
1676 /* The arguments passed to iterate_over_lwps. */
1678 struct iterate_over_lwps_args
1680 /* The FILTER argument passed to iterate_over_lwps. */
1683 /* The CALLBACK argument passed to iterate_over_lwps. */
1684 iterate_over_lwps_ftype
*callback
;
1686 /* The DATA argument passed to iterate_over_lwps. */
1690 /* Callback for find_inferior used by iterate_over_lwps to filter
1691 calls to the callback supplied to that function. Returning a
1692 nonzero value causes find_inferiors to stop iterating and return
1693 the current inferior_list_entry. Returning zero indicates that
1694 find_inferiors should continue iterating. */
1697 iterate_over_lwps_filter (struct inferior_list_entry
*entry
, void *args_p
)
1699 struct iterate_over_lwps_args
*args
1700 = (struct iterate_over_lwps_args
*) args_p
;
1702 if (ptid_match (entry
->id
, args
->filter
))
1704 struct thread_info
*thr
= (struct thread_info
*) entry
;
1705 struct lwp_info
*lwp
= get_thread_lwp (thr
);
1707 return (*args
->callback
) (lwp
, args
->data
);
1713 /* See nat/linux-nat.h. */
1716 iterate_over_lwps (ptid_t filter
,
1717 iterate_over_lwps_ftype callback
,
1720 struct iterate_over_lwps_args args
= {filter
, callback
, data
};
1721 struct inferior_list_entry
*entry
;
1723 entry
= find_inferior (&all_threads
, iterate_over_lwps_filter
, &args
);
1727 return get_thread_lwp ((struct thread_info
*) entry
);
1730 /* Detect zombie thread group leaders, and "exit" them. We can't reap
1731 their exits until all other threads in the group have exited. */
1734 check_zombie_leaders (void)
1736 struct process_info
*proc
, *tmp
;
1738 ALL_PROCESSES (proc
, tmp
)
1740 pid_t leader_pid
= pid_of (proc
);
1741 struct lwp_info
*leader_lp
;
1743 leader_lp
= find_lwp_pid (pid_to_ptid (leader_pid
));
1746 debug_printf ("leader_pid=%d, leader_lp!=NULL=%d, "
1747 "num_lwps=%d, zombie=%d\n",
1748 leader_pid
, leader_lp
!= NULL
, num_lwps (leader_pid
),
1749 linux_proc_pid_is_zombie (leader_pid
));
1751 if (leader_lp
!= NULL
&& !leader_lp
->stopped
1752 /* Check if there are other threads in the group, as we may
1753 have raced with the inferior simply exiting. */
1754 && !last_thread_of_process_p (leader_pid
)
1755 && linux_proc_pid_is_zombie (leader_pid
))
1757 /* A leader zombie can mean one of two things:
1759 - It exited, and there's an exit status pending
1760 available, or only the leader exited (not the whole
1761 program). In the latter case, we can't waitpid the
1762 leader's exit status until all other threads are gone.
1764 - There are 3 or more threads in the group, and a thread
1765 other than the leader exec'd. On an exec, the Linux
1766 kernel destroys all other threads (except the execing
1767 one) in the thread group, and resets the execing thread's
1768 tid to the tgid. No exit notification is sent for the
1769 execing thread -- from the ptracer's perspective, it
1770 appears as though the execing thread just vanishes.
1771 Until we reap all other threads except the leader and the
1772 execing thread, the leader will be zombie, and the
1773 execing thread will be in `D (disc sleep)'. As soon as
1774 all other threads are reaped, the execing thread changes
1775 it's tid to the tgid, and the previous (zombie) leader
1776 vanishes, giving place to the "new" leader. We could try
1777 distinguishing the exit and exec cases, by waiting once
1778 more, and seeing if something comes out, but it doesn't
1779 sound useful. The previous leader _does_ go away, and
1780 we'll re-add the new one once we see the exec event
1781 (which is just the same as what would happen if the
1782 previous leader did exit voluntarily before some other
1787 "CZL: Thread group leader %d zombie "
1788 "(it exited, or another thread execd).\n",
1791 delete_lwp (leader_lp
);
1796 /* Callback for `find_inferior'. Returns the first LWP that is not
1797 stopped. ARG is a PTID filter. */
1800 not_stopped_callback (struct inferior_list_entry
*entry
, void *arg
)
1802 struct thread_info
*thr
= (struct thread_info
*) entry
;
1803 struct lwp_info
*lwp
;
1804 ptid_t filter
= *(ptid_t
*) arg
;
1806 if (!ptid_match (ptid_of (thr
), filter
))
1809 lwp
= get_thread_lwp (thr
);
1816 /* Increment LWP's suspend count. */
1819 lwp_suspended_inc (struct lwp_info
*lwp
)
1823 if (debug_threads
&& lwp
->suspended
> 4)
1825 struct thread_info
*thread
= get_lwp_thread (lwp
);
1827 debug_printf ("LWP %ld has a suspiciously high suspend count,"
1828 " suspended=%d\n", lwpid_of (thread
), lwp
->suspended
);
1832 /* Decrement LWP's suspend count. */
1835 lwp_suspended_decr (struct lwp_info
*lwp
)
1839 if (lwp
->suspended
< 0)
1841 struct thread_info
*thread
= get_lwp_thread (lwp
);
1843 internal_error (__FILE__
, __LINE__
,
1844 "unsuspend LWP %ld, suspended=%d\n", lwpid_of (thread
),
1849 /* This function should only be called if the LWP got a SIGTRAP.
1851 Handle any tracepoint steps or hits. Return true if a tracepoint
1852 event was handled, 0 otherwise. */
1855 handle_tracepoints (struct lwp_info
*lwp
)
1857 struct thread_info
*tinfo
= get_lwp_thread (lwp
);
1858 int tpoint_related_event
= 0;
1860 gdb_assert (lwp
->suspended
== 0);
1862 /* If this tracepoint hit causes a tracing stop, we'll immediately
1863 uninsert tracepoints. To do this, we temporarily pause all
1864 threads, unpatch away, and then unpause threads. We need to make
1865 sure the unpausing doesn't resume LWP too. */
1866 lwp_suspended_inc (lwp
);
1868 /* And we need to be sure that any all-threads-stopping doesn't try
1869 to move threads out of the jump pads, as it could deadlock the
1870 inferior (LWP could be in the jump pad, maybe even holding the
1873 /* Do any necessary step collect actions. */
1874 tpoint_related_event
|= tracepoint_finished_step (tinfo
, lwp
->stop_pc
);
1876 tpoint_related_event
|= handle_tracepoint_bkpts (tinfo
, lwp
->stop_pc
);
1878 /* See if we just hit a tracepoint and do its main collect
1880 tpoint_related_event
|= tracepoint_was_hit (tinfo
, lwp
->stop_pc
);
1882 lwp_suspended_decr (lwp
);
1884 gdb_assert (lwp
->suspended
== 0);
1885 gdb_assert (!stabilizing_threads
|| lwp
->collecting_fast_tracepoint
);
1887 if (tpoint_related_event
)
1890 debug_printf ("got a tracepoint event\n");
1897 /* Convenience wrapper. Returns true if LWP is presently collecting a
1901 linux_fast_tracepoint_collecting (struct lwp_info
*lwp
,
1902 struct fast_tpoint_collect_status
*status
)
1904 CORE_ADDR thread_area
;
1905 struct thread_info
*thread
= get_lwp_thread (lwp
);
1907 if (the_low_target
.get_thread_area
== NULL
)
1910 /* Get the thread area address. This is used to recognize which
1911 thread is which when tracing with the in-process agent library.
1912 We don't read anything from the address, and treat it as opaque;
1913 it's the address itself that we assume is unique per-thread. */
1914 if ((*the_low_target
.get_thread_area
) (lwpid_of (thread
), &thread_area
) == -1)
1917 return fast_tracepoint_collecting (thread_area
, lwp
->stop_pc
, status
);
1920 /* The reason we resume in the caller, is because we want to be able
1921 to pass lwp->status_pending as WSTAT, and we need to clear
1922 status_pending_p before resuming, otherwise, linux_resume_one_lwp
1923 refuses to resume. */
1926 maybe_move_out_of_jump_pad (struct lwp_info
*lwp
, int *wstat
)
1928 struct thread_info
*saved_thread
;
1930 saved_thread
= current_thread
;
1931 current_thread
= get_lwp_thread (lwp
);
1934 || (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) != SIGTRAP
))
1935 && supports_fast_tracepoints ()
1936 && agent_loaded_p ())
1938 struct fast_tpoint_collect_status status
;
1942 debug_printf ("Checking whether LWP %ld needs to move out of the "
1944 lwpid_of (current_thread
));
1946 r
= linux_fast_tracepoint_collecting (lwp
, &status
);
1949 || (WSTOPSIG (*wstat
) != SIGILL
1950 && WSTOPSIG (*wstat
) != SIGFPE
1951 && WSTOPSIG (*wstat
) != SIGSEGV
1952 && WSTOPSIG (*wstat
) != SIGBUS
))
1954 lwp
->collecting_fast_tracepoint
= r
;
1958 if (r
== 1 && lwp
->exit_jump_pad_bkpt
== NULL
)
1960 /* Haven't executed the original instruction yet.
1961 Set breakpoint there, and wait till it's hit,
1962 then single-step until exiting the jump pad. */
1963 lwp
->exit_jump_pad_bkpt
1964 = set_breakpoint_at (status
.adjusted_insn_addr
, NULL
);
1968 debug_printf ("Checking whether LWP %ld needs to move out of "
1969 "the jump pad...it does\n",
1970 lwpid_of (current_thread
));
1971 current_thread
= saved_thread
;
1978 /* If we get a synchronous signal while collecting, *and*
1979 while executing the (relocated) original instruction,
1980 reset the PC to point at the tpoint address, before
1981 reporting to GDB. Otherwise, it's an IPA lib bug: just
1982 report the signal to GDB, and pray for the best. */
1984 lwp
->collecting_fast_tracepoint
= 0;
1987 && (status
.adjusted_insn_addr
<= lwp
->stop_pc
1988 && lwp
->stop_pc
< status
.adjusted_insn_addr_end
))
1991 struct regcache
*regcache
;
1993 /* The si_addr on a few signals references the address
1994 of the faulting instruction. Adjust that as
1996 if ((WSTOPSIG (*wstat
) == SIGILL
1997 || WSTOPSIG (*wstat
) == SIGFPE
1998 || WSTOPSIG (*wstat
) == SIGBUS
1999 || WSTOPSIG (*wstat
) == SIGSEGV
)
2000 && ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
2001 (PTRACE_TYPE_ARG3
) 0, &info
) == 0
2002 /* Final check just to make sure we don't clobber
2003 the siginfo of non-kernel-sent signals. */
2004 && (uintptr_t) info
.si_addr
== lwp
->stop_pc
)
2006 info
.si_addr
= (void *) (uintptr_t) status
.tpoint_addr
;
2007 ptrace (PTRACE_SETSIGINFO
, lwpid_of (current_thread
),
2008 (PTRACE_TYPE_ARG3
) 0, &info
);
2011 regcache
= get_thread_regcache (current_thread
, 1);
2012 (*the_low_target
.set_pc
) (regcache
, status
.tpoint_addr
);
2013 lwp
->stop_pc
= status
.tpoint_addr
;
2015 /* Cancel any fast tracepoint lock this thread was
2017 force_unlock_trace_buffer ();
2020 if (lwp
->exit_jump_pad_bkpt
!= NULL
)
2023 debug_printf ("Cancelling fast exit-jump-pad: removing bkpt. "
2024 "stopping all threads momentarily.\n");
2026 stop_all_lwps (1, lwp
);
2028 delete_breakpoint (lwp
->exit_jump_pad_bkpt
);
2029 lwp
->exit_jump_pad_bkpt
= NULL
;
2031 unstop_all_lwps (1, lwp
);
2033 gdb_assert (lwp
->suspended
>= 0);
2039 debug_printf ("Checking whether LWP %ld needs to move out of the "
2041 lwpid_of (current_thread
));
2043 current_thread
= saved_thread
;
2047 /* Enqueue one signal in the "signals to report later when out of the
2051 enqueue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
2053 struct pending_signals
*p_sig
;
2054 struct thread_info
*thread
= get_lwp_thread (lwp
);
2057 debug_printf ("Deferring signal %d for LWP %ld.\n",
2058 WSTOPSIG (*wstat
), lwpid_of (thread
));
2062 struct pending_signals
*sig
;
2064 for (sig
= lwp
->pending_signals_to_report
;
2067 debug_printf (" Already queued %d\n",
2070 debug_printf (" (no more currently queued signals)\n");
2073 /* Don't enqueue non-RT signals if they are already in the deferred
2074 queue. (SIGSTOP being the easiest signal to see ending up here
2076 if (WSTOPSIG (*wstat
) < __SIGRTMIN
)
2078 struct pending_signals
*sig
;
2080 for (sig
= lwp
->pending_signals_to_report
;
2084 if (sig
->signal
== WSTOPSIG (*wstat
))
2087 debug_printf ("Not requeuing already queued non-RT signal %d"
2096 p_sig
= XCNEW (struct pending_signals
);
2097 p_sig
->prev
= lwp
->pending_signals_to_report
;
2098 p_sig
->signal
= WSTOPSIG (*wstat
);
2100 ptrace (PTRACE_GETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
2103 lwp
->pending_signals_to_report
= p_sig
;
2106 /* Dequeue one signal from the "signals to report later when out of
2107 the jump pad" list. */
2110 dequeue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
2112 struct thread_info
*thread
= get_lwp_thread (lwp
);
2114 if (lwp
->pending_signals_to_report
!= NULL
)
2116 struct pending_signals
**p_sig
;
2118 p_sig
= &lwp
->pending_signals_to_report
;
2119 while ((*p_sig
)->prev
!= NULL
)
2120 p_sig
= &(*p_sig
)->prev
;
2122 *wstat
= W_STOPCODE ((*p_sig
)->signal
);
2123 if ((*p_sig
)->info
.si_signo
!= 0)
2124 ptrace (PTRACE_SETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
2130 debug_printf ("Reporting deferred signal %d for LWP %ld.\n",
2131 WSTOPSIG (*wstat
), lwpid_of (thread
));
2135 struct pending_signals
*sig
;
2137 for (sig
= lwp
->pending_signals_to_report
;
2140 debug_printf (" Still queued %d\n",
2143 debug_printf (" (no more queued signals)\n");
2152 /* Fetch the possibly triggered data watchpoint info and store it in
2155 On some archs, like x86, that use debug registers to set
2156 watchpoints, it's possible that the way to know which watched
2157 address trapped, is to check the register that is used to select
2158 which address to watch. Problem is, between setting the watchpoint
2159 and reading back which data address trapped, the user may change
2160 the set of watchpoints, and, as a consequence, GDB changes the
2161 debug registers in the inferior. To avoid reading back a stale
2162 stopped-data-address when that happens, we cache in LP the fact
2163 that a watchpoint trapped, and the corresponding data address, as
2164 soon as we see CHILD stop with a SIGTRAP. If GDB changes the debug
2165 registers meanwhile, we have the cached data we can rely on. */
2168 check_stopped_by_watchpoint (struct lwp_info
*child
)
2170 if (the_low_target
.stopped_by_watchpoint
!= NULL
)
2172 struct thread_info
*saved_thread
;
2174 saved_thread
= current_thread
;
2175 current_thread
= get_lwp_thread (child
);
2177 if (the_low_target
.stopped_by_watchpoint ())
2179 child
->stop_reason
= TARGET_STOPPED_BY_WATCHPOINT
;
2181 if (the_low_target
.stopped_data_address
!= NULL
)
2182 child
->stopped_data_address
2183 = the_low_target
.stopped_data_address ();
2185 child
->stopped_data_address
= 0;
2188 current_thread
= saved_thread
;
2191 return child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
;
2194 /* Return the ptrace options that we want to try to enable. */
2197 linux_low_ptrace_options (int attached
)
2202 options
|= PTRACE_O_EXITKILL
;
2204 if (report_fork_events
)
2205 options
|= PTRACE_O_TRACEFORK
;
2207 if (report_vfork_events
)
2208 options
|= (PTRACE_O_TRACEVFORK
| PTRACE_O_TRACEVFORKDONE
);
2210 if (report_exec_events
)
2211 options
|= PTRACE_O_TRACEEXEC
;
2216 /* Do low-level handling of the event, and check if we should go on
2217 and pass it to caller code. Return the affected lwp if we are, or
2220 static struct lwp_info
*
2221 linux_low_filter_event (int lwpid
, int wstat
)
2223 struct lwp_info
*child
;
2224 struct thread_info
*thread
;
2225 int have_stop_pc
= 0;
2227 child
= find_lwp_pid (pid_to_ptid (lwpid
));
2229 /* Check for stop events reported by a process we didn't already
2230 know about - anything not already in our LWP list.
2232 If we're expecting to receive stopped processes after
2233 fork, vfork, and clone events, then we'll just add the
2234 new one to our list and go back to waiting for the event
2235 to be reported - the stopped process might be returned
2236 from waitpid before or after the event is.
2238 But note the case of a non-leader thread exec'ing after the
2239 leader having exited, and gone from our lists (because
2240 check_zombie_leaders deleted it). The non-leader thread
2241 changes its tid to the tgid. */
2243 if (WIFSTOPPED (wstat
) && child
== NULL
&& WSTOPSIG (wstat
) == SIGTRAP
2244 && linux_ptrace_get_extended_event (wstat
) == PTRACE_EVENT_EXEC
)
2248 /* A multi-thread exec after we had seen the leader exiting. */
2251 debug_printf ("LLW: Re-adding thread group leader LWP %d"
2252 "after exec.\n", lwpid
);
2255 child_ptid
= ptid_build (lwpid
, lwpid
, 0);
2256 child
= add_lwp (child_ptid
);
2258 current_thread
= child
->thread
;
2261 /* If we didn't find a process, one of two things presumably happened:
2262 - A process we started and then detached from has exited. Ignore it.
2263 - A process we are controlling has forked and the new child's stop
2264 was reported to us by the kernel. Save its PID. */
2265 if (child
== NULL
&& WIFSTOPPED (wstat
))
2267 add_to_pid_list (&stopped_pids
, lwpid
, wstat
);
2270 else if (child
== NULL
)
2273 thread
= get_lwp_thread (child
);
2277 child
->last_status
= wstat
;
2279 /* Check if the thread has exited. */
2280 if ((WIFEXITED (wstat
) || WIFSIGNALED (wstat
)))
2283 debug_printf ("LLFE: %d exited.\n", lwpid
);
2284 /* If there is at least one more LWP, then the exit signal was
2285 not the end of the debugged application and should be
2286 ignored, unless GDB wants to hear about thread exits. */
2287 if (report_thread_events
2288 || last_thread_of_process_p (pid_of (thread
)))
2290 /* Since events are serialized to GDB core, and we can't
2291 report this one right now. Leave the status pending for
2292 the next time we're able to report it. */
2293 mark_lwp_dead (child
, wstat
);
2303 gdb_assert (WIFSTOPPED (wstat
));
2305 if (WIFSTOPPED (wstat
))
2307 struct process_info
*proc
;
2309 /* Architecture-specific setup after inferior is running. */
2310 proc
= find_process_pid (pid_of (thread
));
2311 if (proc
->tdesc
== NULL
)
2315 /* This needs to happen after we have attached to the
2316 inferior and it is stopped for the first time, but
2317 before we access any inferior registers. */
2318 linux_arch_setup_thread (thread
);
2322 /* The process is started, but GDBserver will do
2323 architecture-specific setup after the program stops at
2324 the first instruction. */
2325 child
->status_pending_p
= 1;
2326 child
->status_pending
= wstat
;
2332 if (WIFSTOPPED (wstat
) && child
->must_set_ptrace_flags
)
2334 struct process_info
*proc
= find_process_pid (pid_of (thread
));
2335 int options
= linux_low_ptrace_options (proc
->attached
);
2337 linux_enable_event_reporting (lwpid
, options
);
2338 child
->must_set_ptrace_flags
= 0;
2341 /* Be careful to not overwrite stop_pc until
2342 check_stopped_by_breakpoint is called. */
2343 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGTRAP
2344 && linux_is_extended_waitstatus (wstat
))
2346 child
->stop_pc
= get_pc (child
);
2347 if (handle_extended_wait (&child
, wstat
))
2349 /* The event has been handled, so just return without
2355 /* Check first whether this was a SW/HW breakpoint before checking
2356 watchpoints, because at least s390 can't tell the data address of
2357 hardware watchpoint hits, and returns stopped-by-watchpoint as
2358 long as there's a watchpoint set. */
2359 if (WIFSTOPPED (wstat
) && linux_wstatus_maybe_breakpoint (wstat
))
2361 if (check_stopped_by_breakpoint (child
))
2365 /* Note that TRAP_HWBKPT can indicate either a hardware breakpoint
2366 or hardware watchpoint. Check which is which if we got
2367 TARGET_STOPPED_BY_HW_BREAKPOINT. Likewise, we may have single
2368 stepped an instruction that triggered a watchpoint. In that
2369 case, on some architectures (such as x86), instead of
2370 TRAP_HWBKPT, si_code indicates TRAP_TRACE, and we need to check
2371 the debug registers separately. */
2372 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGTRAP
2373 && child
->stop_reason
!= TARGET_STOPPED_BY_SW_BREAKPOINT
)
2374 check_stopped_by_watchpoint (child
);
2377 child
->stop_pc
= get_pc (child
);
2379 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGSTOP
2380 && child
->stop_expected
)
2383 debug_printf ("Expected stop.\n");
2384 child
->stop_expected
= 0;
2386 if (thread
->last_resume_kind
== resume_stop
)
2388 /* We want to report the stop to the core. Treat the
2389 SIGSTOP as a normal event. */
2391 debug_printf ("LLW: resume_stop SIGSTOP caught for %s.\n",
2392 target_pid_to_str (ptid_of (thread
)));
2394 else if (stopping_threads
!= NOT_STOPPING_THREADS
)
2396 /* Stopping threads. We don't want this SIGSTOP to end up
2399 debug_printf ("LLW: SIGSTOP caught for %s "
2400 "while stopping threads.\n",
2401 target_pid_to_str (ptid_of (thread
)));
2406 /* This is a delayed SIGSTOP. Filter out the event. */
2408 debug_printf ("LLW: %s %s, 0, 0 (discard delayed SIGSTOP)\n",
2409 child
->stepping
? "step" : "continue",
2410 target_pid_to_str (ptid_of (thread
)));
2412 linux_resume_one_lwp (child
, child
->stepping
, 0, NULL
);
2417 child
->status_pending_p
= 1;
2418 child
->status_pending
= wstat
;
2422 /* Resume LWPs that are currently stopped without any pending status
2423 to report, but are resumed from the core's perspective. */
2426 resume_stopped_resumed_lwps (struct inferior_list_entry
*entry
)
2428 struct thread_info
*thread
= (struct thread_info
*) entry
;
2429 struct lwp_info
*lp
= get_thread_lwp (thread
);
2433 && !lp
->status_pending_p
2434 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
)
2436 int step
= thread
->last_resume_kind
== resume_step
;
2439 debug_printf ("RSRL: resuming stopped-resumed LWP %s at %s: step=%d\n",
2440 target_pid_to_str (ptid_of (thread
)),
2441 paddress (lp
->stop_pc
),
2444 linux_resume_one_lwp (lp
, step
, GDB_SIGNAL_0
, NULL
);
2448 /* Wait for an event from child(ren) WAIT_PTID, and return any that
2449 match FILTER_PTID (leaving others pending). The PTIDs can be:
2450 minus_one_ptid, to specify any child; a pid PTID, specifying all
2451 lwps of a thread group; or a PTID representing a single lwp. Store
2452 the stop status through the status pointer WSTAT. OPTIONS is
2453 passed to the waitpid call. Return 0 if no event was found and
2454 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
2455 was found. Return the PID of the stopped child otherwise. */
2458 linux_wait_for_event_filtered (ptid_t wait_ptid
, ptid_t filter_ptid
,
2459 int *wstatp
, int options
)
2461 struct thread_info
*event_thread
;
2462 struct lwp_info
*event_child
, *requested_child
;
2463 sigset_t block_mask
, prev_mask
;
2466 /* N.B. event_thread points to the thread_info struct that contains
2467 event_child. Keep them in sync. */
2468 event_thread
= NULL
;
2470 requested_child
= NULL
;
2472 /* Check for a lwp with a pending status. */
2474 if (ptid_equal (filter_ptid
, minus_one_ptid
) || ptid_is_pid (filter_ptid
))
2476 event_thread
= (struct thread_info
*)
2477 find_inferior (&all_threads
, status_pending_p_callback
, &filter_ptid
);
2478 if (event_thread
!= NULL
)
2479 event_child
= get_thread_lwp (event_thread
);
2480 if (debug_threads
&& event_thread
)
2481 debug_printf ("Got a pending child %ld\n", lwpid_of (event_thread
));
2483 else if (!ptid_equal (filter_ptid
, null_ptid
))
2485 requested_child
= find_lwp_pid (filter_ptid
);
2487 if (stopping_threads
== NOT_STOPPING_THREADS
2488 && requested_child
->status_pending_p
2489 && requested_child
->collecting_fast_tracepoint
)
2491 enqueue_one_deferred_signal (requested_child
,
2492 &requested_child
->status_pending
);
2493 requested_child
->status_pending_p
= 0;
2494 requested_child
->status_pending
= 0;
2495 linux_resume_one_lwp (requested_child
, 0, 0, NULL
);
2498 if (requested_child
->suspended
2499 && requested_child
->status_pending_p
)
2501 internal_error (__FILE__
, __LINE__
,
2502 "requesting an event out of a"
2503 " suspended child?");
2506 if (requested_child
->status_pending_p
)
2508 event_child
= requested_child
;
2509 event_thread
= get_lwp_thread (event_child
);
2513 if (event_child
!= NULL
)
2516 debug_printf ("Got an event from pending child %ld (%04x)\n",
2517 lwpid_of (event_thread
), event_child
->status_pending
);
2518 *wstatp
= event_child
->status_pending
;
2519 event_child
->status_pending_p
= 0;
2520 event_child
->status_pending
= 0;
2521 current_thread
= event_thread
;
2522 return lwpid_of (event_thread
);
2525 /* But if we don't find a pending event, we'll have to wait.
2527 We only enter this loop if no process has a pending wait status.
2528 Thus any action taken in response to a wait status inside this
2529 loop is responding as soon as we detect the status, not after any
2532 /* Make sure SIGCHLD is blocked until the sigsuspend below. Block
2533 all signals while here. */
2534 sigfillset (&block_mask
);
2535 sigprocmask (SIG_BLOCK
, &block_mask
, &prev_mask
);
2537 /* Always pull all events out of the kernel. We'll randomly select
2538 an event LWP out of all that have events, to prevent
2540 while (event_child
== NULL
)
2544 /* Always use -1 and WNOHANG, due to couple of a kernel/ptrace
2547 - If the thread group leader exits while other threads in the
2548 thread group still exist, waitpid(TGID, ...) hangs. That
2549 waitpid won't return an exit status until the other threads
2550 in the group are reaped.
2552 - When a non-leader thread execs, that thread just vanishes
2553 without reporting an exit (so we'd hang if we waited for it
2554 explicitly in that case). The exec event is reported to
2557 ret
= my_waitpid (-1, wstatp
, options
| WNOHANG
);
2560 debug_printf ("LWFE: waitpid(-1, ...) returned %d, %s\n",
2561 ret
, errno
? strerror (errno
) : "ERRNO-OK");
2567 debug_printf ("LLW: waitpid %ld received %s\n",
2568 (long) ret
, status_to_str (*wstatp
));
2571 /* Filter all events. IOW, leave all events pending. We'll
2572 randomly select an event LWP out of all that have events
2574 linux_low_filter_event (ret
, *wstatp
);
2575 /* Retry until nothing comes out of waitpid. A single
2576 SIGCHLD can indicate more than one child stopped. */
2580 /* Now that we've pulled all events out of the kernel, resume
2581 LWPs that don't have an interesting event to report. */
2582 if (stopping_threads
== NOT_STOPPING_THREADS
)
2583 for_each_inferior (&all_threads
, resume_stopped_resumed_lwps
);
2585 /* ... and find an LWP with a status to report to the core, if
2587 event_thread
= (struct thread_info
*)
2588 find_inferior (&all_threads
, status_pending_p_callback
, &filter_ptid
);
2589 if (event_thread
!= NULL
)
2591 event_child
= get_thread_lwp (event_thread
);
2592 *wstatp
= event_child
->status_pending
;
2593 event_child
->status_pending_p
= 0;
2594 event_child
->status_pending
= 0;
2598 /* Check for zombie thread group leaders. Those can't be reaped
2599 until all other threads in the thread group are. */
2600 check_zombie_leaders ();
2602 /* If there are no resumed children left in the set of LWPs we
2603 want to wait for, bail. We can't just block in
2604 waitpid/sigsuspend, because lwps might have been left stopped
2605 in trace-stop state, and we'd be stuck forever waiting for
2606 their status to change (which would only happen if we resumed
2607 them). Even if WNOHANG is set, this return code is preferred
2608 over 0 (below), as it is more detailed. */
2609 if ((find_inferior (&all_threads
,
2610 not_stopped_callback
,
2611 &wait_ptid
) == NULL
))
2614 debug_printf ("LLW: exit (no unwaited-for LWP)\n");
2615 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2619 /* No interesting event to report to the caller. */
2620 if ((options
& WNOHANG
))
2623 debug_printf ("WNOHANG set, no event found\n");
2625 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2629 /* Block until we get an event reported with SIGCHLD. */
2631 debug_printf ("sigsuspend'ing\n");
2633 sigsuspend (&prev_mask
);
2634 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2638 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2640 current_thread
= event_thread
;
2642 return lwpid_of (event_thread
);
2645 /* Wait for an event from child(ren) PTID. PTIDs can be:
2646 minus_one_ptid, to specify any child; a pid PTID, specifying all
2647 lwps of a thread group; or a PTID representing a single lwp. Store
2648 the stop status through the status pointer WSTAT. OPTIONS is
2649 passed to the waitpid call. Return 0 if no event was found and
2650 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
2651 was found. Return the PID of the stopped child otherwise. */
2654 linux_wait_for_event (ptid_t ptid
, int *wstatp
, int options
)
2656 return linux_wait_for_event_filtered (ptid
, ptid
, wstatp
, options
);
2659 /* Count the LWP's that have had events. */
2662 count_events_callback (struct inferior_list_entry
*entry
, void *data
)
2664 struct thread_info
*thread
= (struct thread_info
*) entry
;
2665 struct lwp_info
*lp
= get_thread_lwp (thread
);
2666 int *count
= (int *) data
;
2668 gdb_assert (count
!= NULL
);
2670 /* Count only resumed LWPs that have an event pending. */
2671 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2672 && lp
->status_pending_p
)
2678 /* Select the LWP (if any) that is currently being single-stepped. */
2681 select_singlestep_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
2683 struct thread_info
*thread
= (struct thread_info
*) entry
;
2684 struct lwp_info
*lp
= get_thread_lwp (thread
);
2686 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2687 && thread
->last_resume_kind
== resume_step
2688 && lp
->status_pending_p
)
2694 /* Select the Nth LWP that has had an event. */
2697 select_event_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
2699 struct thread_info
*thread
= (struct thread_info
*) entry
;
2700 struct lwp_info
*lp
= get_thread_lwp (thread
);
2701 int *selector
= (int *) data
;
2703 gdb_assert (selector
!= NULL
);
2705 /* Select only resumed LWPs that have an event pending. */
2706 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2707 && lp
->status_pending_p
)
2708 if ((*selector
)-- == 0)
2714 /* Select one LWP out of those that have events pending. */
2717 select_event_lwp (struct lwp_info
**orig_lp
)
2720 int random_selector
;
2721 struct thread_info
*event_thread
= NULL
;
2723 /* In all-stop, give preference to the LWP that is being
2724 single-stepped. There will be at most one, and it's the LWP that
2725 the core is most interested in. If we didn't do this, then we'd
2726 have to handle pending step SIGTRAPs somehow in case the core
2727 later continues the previously-stepped thread, otherwise we'd
2728 report the pending SIGTRAP, and the core, not having stepped the
2729 thread, wouldn't understand what the trap was for, and therefore
2730 would report it to the user as a random signal. */
2734 = (struct thread_info
*) find_inferior (&all_threads
,
2735 select_singlestep_lwp_callback
,
2737 if (event_thread
!= NULL
)
2740 debug_printf ("SEL: Select single-step %s\n",
2741 target_pid_to_str (ptid_of (event_thread
)));
2744 if (event_thread
== NULL
)
2746 /* No single-stepping LWP. Select one at random, out of those
2747 which have had events. */
2749 /* First see how many events we have. */
2750 find_inferior (&all_threads
, count_events_callback
, &num_events
);
2751 gdb_assert (num_events
> 0);
2753 /* Now randomly pick a LWP out of those that have had
2755 random_selector
= (int)
2756 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
2758 if (debug_threads
&& num_events
> 1)
2759 debug_printf ("SEL: Found %d SIGTRAP events, selecting #%d\n",
2760 num_events
, random_selector
);
2763 = (struct thread_info
*) find_inferior (&all_threads
,
2764 select_event_lwp_callback
,
2768 if (event_thread
!= NULL
)
2770 struct lwp_info
*event_lp
= get_thread_lwp (event_thread
);
2772 /* Switch the event LWP. */
2773 *orig_lp
= event_lp
;
2777 /* Decrement the suspend count of an LWP. */
2780 unsuspend_one_lwp (struct inferior_list_entry
*entry
, void *except
)
2782 struct thread_info
*thread
= (struct thread_info
*) entry
;
2783 struct lwp_info
*lwp
= get_thread_lwp (thread
);
2785 /* Ignore EXCEPT. */
2789 lwp_suspended_decr (lwp
);
2793 /* Decrement the suspend count of all LWPs, except EXCEPT, if non
2797 unsuspend_all_lwps (struct lwp_info
*except
)
2799 find_inferior (&all_threads
, unsuspend_one_lwp
, except
);
2802 static void move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
);
2803 static int stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
,
2805 static int lwp_running (struct inferior_list_entry
*entry
, void *data
);
2806 static ptid_t
linux_wait_1 (ptid_t ptid
,
2807 struct target_waitstatus
*ourstatus
,
2808 int target_options
);
2810 /* Stabilize threads (move out of jump pads).
2812 If a thread is midway collecting a fast tracepoint, we need to
2813 finish the collection and move it out of the jump pad before
2814 reporting the signal.
2816 This avoids recursion while collecting (when a signal arrives
2817 midway, and the signal handler itself collects), which would trash
2818 the trace buffer. In case the user set a breakpoint in a signal
2819 handler, this avoids the backtrace showing the jump pad, etc..
2820 Most importantly, there are certain things we can't do safely if
2821 threads are stopped in a jump pad (or in its callee's). For
2824 - starting a new trace run. A thread still collecting the
2825 previous run, could trash the trace buffer when resumed. The trace
2826 buffer control structures would have been reset but the thread had
2827 no way to tell. The thread could even midway memcpy'ing to the
2828 buffer, which would mean that when resumed, it would clobber the
2829 trace buffer that had been set for a new run.
2831 - we can't rewrite/reuse the jump pads for new tracepoints
2832 safely. Say you do tstart while a thread is stopped midway while
2833 collecting. When the thread is later resumed, it finishes the
2834 collection, and returns to the jump pad, to execute the original
2835 instruction that was under the tracepoint jump at the time the
2836 older run had been started. If the jump pad had been rewritten
2837 since for something else in the new run, the thread would now
2838 execute the wrong / random instructions. */
2841 linux_stabilize_threads (void)
2843 struct thread_info
*saved_thread
;
2844 struct thread_info
*thread_stuck
;
2847 = (struct thread_info
*) find_inferior (&all_threads
,
2848 stuck_in_jump_pad_callback
,
2850 if (thread_stuck
!= NULL
)
2853 debug_printf ("can't stabilize, LWP %ld is stuck in jump pad\n",
2854 lwpid_of (thread_stuck
));
2858 saved_thread
= current_thread
;
2860 stabilizing_threads
= 1;
2863 for_each_inferior (&all_threads
, move_out_of_jump_pad_callback
);
2865 /* Loop until all are stopped out of the jump pads. */
2866 while (find_inferior (&all_threads
, lwp_running
, NULL
) != NULL
)
2868 struct target_waitstatus ourstatus
;
2869 struct lwp_info
*lwp
;
2872 /* Note that we go through the full wait even loop. While
2873 moving threads out of jump pad, we need to be able to step
2874 over internal breakpoints and such. */
2875 linux_wait_1 (minus_one_ptid
, &ourstatus
, 0);
2877 if (ourstatus
.kind
== TARGET_WAITKIND_STOPPED
)
2879 lwp
= get_thread_lwp (current_thread
);
2882 lwp_suspended_inc (lwp
);
2884 if (ourstatus
.value
.sig
!= GDB_SIGNAL_0
2885 || current_thread
->last_resume_kind
== resume_stop
)
2887 wstat
= W_STOPCODE (gdb_signal_to_host (ourstatus
.value
.sig
));
2888 enqueue_one_deferred_signal (lwp
, &wstat
);
2893 find_inferior (&all_threads
, unsuspend_one_lwp
, NULL
);
2895 stabilizing_threads
= 0;
2897 current_thread
= saved_thread
;
2902 = (struct thread_info
*) find_inferior (&all_threads
,
2903 stuck_in_jump_pad_callback
,
2905 if (thread_stuck
!= NULL
)
2906 debug_printf ("couldn't stabilize, LWP %ld got stuck in jump pad\n",
2907 lwpid_of (thread_stuck
));
2911 /* Convenience function that is called when the kernel reports an
2912 event that is not passed out to GDB. */
2915 ignore_event (struct target_waitstatus
*ourstatus
)
2917 /* If we got an event, there may still be others, as a single
2918 SIGCHLD can indicate more than one child stopped. This forces
2919 another target_wait call. */
2922 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2926 /* Convenience function that is called when the kernel reports an exit
2927 event. This decides whether to report the event to GDB as a
2928 process exit event, a thread exit event, or to suppress the
2932 filter_exit_event (struct lwp_info
*event_child
,
2933 struct target_waitstatus
*ourstatus
)
2935 struct thread_info
*thread
= get_lwp_thread (event_child
);
2936 ptid_t ptid
= ptid_of (thread
);
2938 if (!last_thread_of_process_p (pid_of (thread
)))
2940 if (report_thread_events
)
2941 ourstatus
->kind
= TARGET_WAITKIND_THREAD_EXITED
;
2943 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2945 delete_lwp (event_child
);
2950 /* Wait for process, returns status. */
2953 linux_wait_1 (ptid_t ptid
,
2954 struct target_waitstatus
*ourstatus
, int target_options
)
2957 struct lwp_info
*event_child
;
2960 int step_over_finished
;
2961 int bp_explains_trap
;
2962 int maybe_internal_trap
;
2970 debug_printf ("linux_wait_1: [%s]\n", target_pid_to_str (ptid
));
2973 /* Translate generic target options into linux options. */
2975 if (target_options
& TARGET_WNOHANG
)
2978 bp_explains_trap
= 0;
2981 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2983 if (ptid_equal (step_over_bkpt
, null_ptid
))
2984 pid
= linux_wait_for_event (ptid
, &w
, options
);
2988 debug_printf ("step_over_bkpt set [%s], doing a blocking wait\n",
2989 target_pid_to_str (step_over_bkpt
));
2990 pid
= linux_wait_for_event (step_over_bkpt
, &w
, options
& ~WNOHANG
);
2995 gdb_assert (target_options
& TARGET_WNOHANG
);
2999 debug_printf ("linux_wait_1 ret = null_ptid, "
3000 "TARGET_WAITKIND_IGNORE\n");
3004 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3011 debug_printf ("linux_wait_1 ret = null_ptid, "
3012 "TARGET_WAITKIND_NO_RESUMED\n");
3016 ourstatus
->kind
= TARGET_WAITKIND_NO_RESUMED
;
3020 event_child
= get_thread_lwp (current_thread
);
3022 /* linux_wait_for_event only returns an exit status for the last
3023 child of a process. Report it. */
3024 if (WIFEXITED (w
) || WIFSIGNALED (w
))
3028 ourstatus
->kind
= TARGET_WAITKIND_EXITED
;
3029 ourstatus
->value
.integer
= WEXITSTATUS (w
);
3033 debug_printf ("linux_wait_1 ret = %s, exited with "
3035 target_pid_to_str (ptid_of (current_thread
)),
3042 ourstatus
->kind
= TARGET_WAITKIND_SIGNALLED
;
3043 ourstatus
->value
.sig
= gdb_signal_from_host (WTERMSIG (w
));
3047 debug_printf ("linux_wait_1 ret = %s, terminated with "
3049 target_pid_to_str (ptid_of (current_thread
)),
3055 if (ourstatus
->kind
== TARGET_WAITKIND_EXITED
)
3056 return filter_exit_event (event_child
, ourstatus
);
3058 return ptid_of (current_thread
);
3061 /* If step-over executes a breakpoint instruction, it means a
3062 gdb/gdbserver breakpoint had been planted on top of a permanent
3063 breakpoint. The PC has been adjusted by
3064 check_stopped_by_breakpoint to point at the breakpoint address.
3065 Advance the PC manually past the breakpoint, otherwise the
3066 program would keep trapping the permanent breakpoint forever. */
3067 if (!ptid_equal (step_over_bkpt
, null_ptid
)
3068 && event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
)
3070 int increment_pc
= 0;
3071 int breakpoint_kind
= 0;
3072 CORE_ADDR stop_pc
= event_child
->stop_pc
;
3074 breakpoint_kind
= the_target
->breakpoint_kind_from_pc (&stop_pc
);
3075 the_target
->sw_breakpoint_from_kind (breakpoint_kind
, &increment_pc
);
3079 debug_printf ("step-over for %s executed software breakpoint\n",
3080 target_pid_to_str (ptid_of (current_thread
)));
3083 if (increment_pc
!= 0)
3085 struct regcache
*regcache
3086 = get_thread_regcache (current_thread
, 1);
3088 event_child
->stop_pc
+= increment_pc
;
3089 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
3091 if (!(*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))
3092 event_child
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3096 /* If this event was not handled before, and is not a SIGTRAP, we
3097 report it. SIGILL and SIGSEGV are also treated as traps in case
3098 a breakpoint is inserted at the current PC. If this target does
3099 not support internal breakpoints at all, we also report the
3100 SIGTRAP without further processing; it's of no concern to us. */
3102 = (supports_breakpoints ()
3103 && (WSTOPSIG (w
) == SIGTRAP
3104 || ((WSTOPSIG (w
) == SIGILL
3105 || WSTOPSIG (w
) == SIGSEGV
)
3106 && (*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))));
3108 if (maybe_internal_trap
)
3110 /* Handle anything that requires bookkeeping before deciding to
3111 report the event or continue waiting. */
3113 /* First check if we can explain the SIGTRAP with an internal
3114 breakpoint, or if we should possibly report the event to GDB.
3115 Do this before anything that may remove or insert a
3117 bp_explains_trap
= breakpoint_inserted_here (event_child
->stop_pc
);
3119 /* We have a SIGTRAP, possibly a step-over dance has just
3120 finished. If so, tweak the state machine accordingly,
3121 reinsert breakpoints and delete any reinsert (software
3122 single-step) breakpoints. */
3123 step_over_finished
= finish_step_over (event_child
);
3125 /* Now invoke the callbacks of any internal breakpoints there. */
3126 check_breakpoints (event_child
->stop_pc
);
3128 /* Handle tracepoint data collecting. This may overflow the
3129 trace buffer, and cause a tracing stop, removing
3131 trace_event
= handle_tracepoints (event_child
);
3133 if (bp_explains_trap
)
3135 /* If we stepped or ran into an internal breakpoint, we've
3136 already handled it. So next time we resume (from this
3137 PC), we should step over it. */
3139 debug_printf ("Hit a gdbserver breakpoint.\n");
3141 if (breakpoint_here (event_child
->stop_pc
))
3142 event_child
->need_step_over
= 1;
3147 /* We have some other signal, possibly a step-over dance was in
3148 progress, and it should be cancelled too. */
3149 step_over_finished
= finish_step_over (event_child
);
3152 /* We have all the data we need. Either report the event to GDB, or
3153 resume threads and keep waiting for more. */
3155 /* If we're collecting a fast tracepoint, finish the collection and
3156 move out of the jump pad before delivering a signal. See
3157 linux_stabilize_threads. */
3160 && WSTOPSIG (w
) != SIGTRAP
3161 && supports_fast_tracepoints ()
3162 && agent_loaded_p ())
3165 debug_printf ("Got signal %d for LWP %ld. Check if we need "
3166 "to defer or adjust it.\n",
3167 WSTOPSIG (w
), lwpid_of (current_thread
));
3169 /* Allow debugging the jump pad itself. */
3170 if (current_thread
->last_resume_kind
!= resume_step
3171 && maybe_move_out_of_jump_pad (event_child
, &w
))
3173 enqueue_one_deferred_signal (event_child
, &w
);
3176 debug_printf ("Signal %d for LWP %ld deferred (in jump pad)\n",
3177 WSTOPSIG (w
), lwpid_of (current_thread
));
3179 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
3181 return ignore_event (ourstatus
);
3185 if (event_child
->collecting_fast_tracepoint
)
3188 debug_printf ("LWP %ld was trying to move out of the jump pad (%d). "
3189 "Check if we're already there.\n",
3190 lwpid_of (current_thread
),
3191 event_child
->collecting_fast_tracepoint
);
3195 event_child
->collecting_fast_tracepoint
3196 = linux_fast_tracepoint_collecting (event_child
, NULL
);
3198 if (event_child
->collecting_fast_tracepoint
!= 1)
3200 /* No longer need this breakpoint. */
3201 if (event_child
->exit_jump_pad_bkpt
!= NULL
)
3204 debug_printf ("No longer need exit-jump-pad bkpt; removing it."
3205 "stopping all threads momentarily.\n");
3207 /* Other running threads could hit this breakpoint.
3208 We don't handle moribund locations like GDB does,
3209 instead we always pause all threads when removing
3210 breakpoints, so that any step-over or
3211 decr_pc_after_break adjustment is always taken
3212 care of while the breakpoint is still
3214 stop_all_lwps (1, event_child
);
3216 delete_breakpoint (event_child
->exit_jump_pad_bkpt
);
3217 event_child
->exit_jump_pad_bkpt
= NULL
;
3219 unstop_all_lwps (1, event_child
);
3221 gdb_assert (event_child
->suspended
>= 0);
3225 if (event_child
->collecting_fast_tracepoint
== 0)
3228 debug_printf ("fast tracepoint finished "
3229 "collecting successfully.\n");
3231 /* We may have a deferred signal to report. */
3232 if (dequeue_one_deferred_signal (event_child
, &w
))
3235 debug_printf ("dequeued one signal.\n");
3240 debug_printf ("no deferred signals.\n");
3242 if (stabilizing_threads
)
3244 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
3245 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
3249 debug_printf ("linux_wait_1 ret = %s, stopped "
3250 "while stabilizing threads\n",
3251 target_pid_to_str (ptid_of (current_thread
)));
3255 return ptid_of (current_thread
);
3261 /* Check whether GDB would be interested in this event. */
3263 /* If GDB is not interested in this signal, don't stop other
3264 threads, and don't report it to GDB. Just resume the inferior
3265 right away. We do this for threading-related signals as well as
3266 any that GDB specifically requested we ignore. But never ignore
3267 SIGSTOP if we sent it ourselves, and do not ignore signals when
3268 stepping - they may require special handling to skip the signal
3269 handler. Also never ignore signals that could be caused by a
3271 /* FIXME drow/2002-06-09: Get signal numbers from the inferior's
3274 && current_thread
->last_resume_kind
!= resume_step
3276 #if defined (USE_THREAD_DB) && !defined (__ANDROID__)
3277 (current_process ()->priv
->thread_db
!= NULL
3278 && (WSTOPSIG (w
) == __SIGRTMIN
3279 || WSTOPSIG (w
) == __SIGRTMIN
+ 1))
3282 (pass_signals
[gdb_signal_from_host (WSTOPSIG (w
))]
3283 && !(WSTOPSIG (w
) == SIGSTOP
3284 && current_thread
->last_resume_kind
== resume_stop
)
3285 && !linux_wstatus_maybe_breakpoint (w
))))
3287 siginfo_t info
, *info_p
;
3290 debug_printf ("Ignored signal %d for LWP %ld.\n",
3291 WSTOPSIG (w
), lwpid_of (current_thread
));
3293 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
3294 (PTRACE_TYPE_ARG3
) 0, &info
) == 0)
3299 if (step_over_finished
)
3301 /* We cancelled this thread's step-over above. We still
3302 need to unsuspend all other LWPs, and set them back
3303 running again while the signal handler runs. */
3304 unsuspend_all_lwps (event_child
);
3306 /* Enqueue the pending signal info so that proceed_all_lwps
3308 enqueue_pending_signal (event_child
, WSTOPSIG (w
), info_p
);
3310 proceed_all_lwps ();
3314 linux_resume_one_lwp (event_child
, event_child
->stepping
,
3315 WSTOPSIG (w
), info_p
);
3317 return ignore_event (ourstatus
);
3320 /* Note that all addresses are always "out of the step range" when
3321 there's no range to begin with. */
3322 in_step_range
= lwp_in_step_range (event_child
);
3324 /* If GDB wanted this thread to single step, and the thread is out
3325 of the step range, we always want to report the SIGTRAP, and let
3326 GDB handle it. Watchpoints should always be reported. So should
3327 signals we can't explain. A SIGTRAP we can't explain could be a
3328 GDB breakpoint --- we may or not support Z0 breakpoints. If we
3329 do, we're be able to handle GDB breakpoints on top of internal
3330 breakpoints, by handling the internal breakpoint and still
3331 reporting the event to GDB. If we don't, we're out of luck, GDB
3332 won't see the breakpoint hit. If we see a single-step event but
3333 the thread should be continuing, don't pass the trap to gdb.
3334 That indicates that we had previously finished a single-step but
3335 left the single-step pending -- see
3336 complete_ongoing_step_over. */
3337 report_to_gdb
= (!maybe_internal_trap
3338 || (current_thread
->last_resume_kind
== resume_step
3340 || event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
3342 && !bp_explains_trap
3344 && !step_over_finished
3345 && !(current_thread
->last_resume_kind
== resume_continue
3346 && event_child
->stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
))
3347 || (gdb_breakpoint_here (event_child
->stop_pc
)
3348 && gdb_condition_true_at_breakpoint (event_child
->stop_pc
)
3349 && gdb_no_commands_at_breakpoint (event_child
->stop_pc
))
3350 || event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
);
3352 run_breakpoint_commands (event_child
->stop_pc
);
3354 /* We found no reason GDB would want us to stop. We either hit one
3355 of our own breakpoints, or finished an internal step GDB
3356 shouldn't know about. */
3361 if (bp_explains_trap
)
3362 debug_printf ("Hit a gdbserver breakpoint.\n");
3363 if (step_over_finished
)
3364 debug_printf ("Step-over finished.\n");
3366 debug_printf ("Tracepoint event.\n");
3367 if (lwp_in_step_range (event_child
))
3368 debug_printf ("Range stepping pc 0x%s [0x%s, 0x%s).\n",
3369 paddress (event_child
->stop_pc
),
3370 paddress (event_child
->step_range_start
),
3371 paddress (event_child
->step_range_end
));
3374 /* We're not reporting this breakpoint to GDB, so apply the
3375 decr_pc_after_break adjustment to the inferior's regcache
3378 if (the_low_target
.set_pc
!= NULL
)
3380 struct regcache
*regcache
3381 = get_thread_regcache (current_thread
, 1);
3382 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
3385 /* We may have finished stepping over a breakpoint. If so,
3386 we've stopped and suspended all LWPs momentarily except the
3387 stepping one. This is where we resume them all again. We're
3388 going to keep waiting, so use proceed, which handles stepping
3389 over the next breakpoint. */
3391 debug_printf ("proceeding all threads.\n");
3393 if (step_over_finished
)
3394 unsuspend_all_lwps (event_child
);
3396 proceed_all_lwps ();
3397 return ignore_event (ourstatus
);
3402 if (event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
3406 str
= target_waitstatus_to_string (&event_child
->waitstatus
);
3407 debug_printf ("LWP %ld: extended event with waitstatus %s\n",
3408 lwpid_of (get_lwp_thread (event_child
)), str
);
3411 if (current_thread
->last_resume_kind
== resume_step
)
3413 if (event_child
->step_range_start
== event_child
->step_range_end
)
3414 debug_printf ("GDB wanted to single-step, reporting event.\n");
3415 else if (!lwp_in_step_range (event_child
))
3416 debug_printf ("Out of step range, reporting event.\n");
3418 if (event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
)
3419 debug_printf ("Stopped by watchpoint.\n");
3420 else if (gdb_breakpoint_here (event_child
->stop_pc
))
3421 debug_printf ("Stopped by GDB breakpoint.\n");
3423 debug_printf ("Hit a non-gdbserver trap event.\n");
3426 /* Alright, we're going to report a stop. */
3428 if (!stabilizing_threads
)
3430 /* In all-stop, stop all threads. */
3432 stop_all_lwps (0, NULL
);
3434 /* If we're not waiting for a specific LWP, choose an event LWP
3435 from among those that have had events. Giving equal priority
3436 to all LWPs that have had events helps prevent
3438 if (ptid_equal (ptid
, minus_one_ptid
))
3440 event_child
->status_pending_p
= 1;
3441 event_child
->status_pending
= w
;
3443 select_event_lwp (&event_child
);
3445 /* current_thread and event_child must stay in sync. */
3446 current_thread
= get_lwp_thread (event_child
);
3448 event_child
->status_pending_p
= 0;
3449 w
= event_child
->status_pending
;
3452 if (step_over_finished
)
3456 /* If we were doing a step-over, all other threads but
3457 the stepping one had been paused in start_step_over,
3458 with their suspend counts incremented. We don't want
3459 to do a full unstop/unpause, because we're in
3460 all-stop mode (so we want threads stopped), but we
3461 still need to unsuspend the other threads, to
3462 decrement their `suspended' count back. */
3463 unsuspend_all_lwps (event_child
);
3467 /* If we just finished a step-over, then all threads had
3468 been momentarily paused. In all-stop, that's fine,
3469 we want threads stopped by now anyway. In non-stop,
3470 we need to re-resume threads that GDB wanted to be
3472 unstop_all_lwps (1, event_child
);
3476 /* Stabilize threads (move out of jump pads). */
3478 stabilize_threads ();
3482 /* If we just finished a step-over, then all threads had been
3483 momentarily paused. In all-stop, that's fine, we want
3484 threads stopped by now anyway. In non-stop, we need to
3485 re-resume threads that GDB wanted to be running. */
3486 if (step_over_finished
)
3487 unstop_all_lwps (1, event_child
);
3490 if (event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
3492 /* If the reported event is an exit, fork, vfork or exec, let
3494 *ourstatus
= event_child
->waitstatus
;
3495 /* Clear the event lwp's waitstatus since we handled it already. */
3496 event_child
->waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
3499 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
3501 /* Now that we've selected our final event LWP, un-adjust its PC if
3502 it was a software breakpoint, and the client doesn't know we can
3503 adjust the breakpoint ourselves. */
3504 if (event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3505 && !swbreak_feature
)
3507 int decr_pc
= the_low_target
.decr_pc_after_break
;
3511 struct regcache
*regcache
3512 = get_thread_regcache (current_thread
, 1);
3513 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
+ decr_pc
);
3517 if (current_thread
->last_resume_kind
== resume_stop
3518 && WSTOPSIG (w
) == SIGSTOP
)
3520 /* A thread that has been requested to stop by GDB with vCont;t,
3521 and it stopped cleanly, so report as SIG0. The use of
3522 SIGSTOP is an implementation detail. */
3523 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
3525 else if (current_thread
->last_resume_kind
== resume_stop
3526 && WSTOPSIG (w
) != SIGSTOP
)
3528 /* A thread that has been requested to stop by GDB with vCont;t,
3529 but, it stopped for other reasons. */
3530 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
3532 else if (ourstatus
->kind
== TARGET_WAITKIND_STOPPED
)
3534 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
3537 gdb_assert (ptid_equal (step_over_bkpt
, null_ptid
));
3541 debug_printf ("linux_wait_1 ret = %s, %d, %d\n",
3542 target_pid_to_str (ptid_of (current_thread
)),
3543 ourstatus
->kind
, ourstatus
->value
.sig
);
3547 if (ourstatus
->kind
== TARGET_WAITKIND_EXITED
)
3548 return filter_exit_event (event_child
, ourstatus
);
3550 return ptid_of (current_thread
);
3553 /* Get rid of any pending event in the pipe. */
3555 async_file_flush (void)
3561 ret
= read (linux_event_pipe
[0], &buf
, 1);
3562 while (ret
>= 0 || (ret
== -1 && errno
== EINTR
));
3565 /* Put something in the pipe, so the event loop wakes up. */
3567 async_file_mark (void)
3571 async_file_flush ();
3574 ret
= write (linux_event_pipe
[1], "+", 1);
3575 while (ret
== 0 || (ret
== -1 && errno
== EINTR
));
3577 /* Ignore EAGAIN. If the pipe is full, the event loop will already
3578 be awakened anyway. */
3582 linux_wait (ptid_t ptid
,
3583 struct target_waitstatus
*ourstatus
, int target_options
)
3587 /* Flush the async file first. */
3588 if (target_is_async_p ())
3589 async_file_flush ();
3593 event_ptid
= linux_wait_1 (ptid
, ourstatus
, target_options
);
3595 while ((target_options
& TARGET_WNOHANG
) == 0
3596 && ptid_equal (event_ptid
, null_ptid
)
3597 && ourstatus
->kind
== TARGET_WAITKIND_IGNORE
);
3599 /* If at least one stop was reported, there may be more. A single
3600 SIGCHLD can signal more than one child stop. */
3601 if (target_is_async_p ()
3602 && (target_options
& TARGET_WNOHANG
) != 0
3603 && !ptid_equal (event_ptid
, null_ptid
))
3609 /* Send a signal to an LWP. */
3612 kill_lwp (unsigned long lwpid
, int signo
)
3614 /* Use tkill, if possible, in case we are using nptl threads. If tkill
3615 fails, then we are not using nptl threads and we should be using kill. */
3619 static int tkill_failed
;
3626 ret
= syscall (__NR_tkill
, lwpid
, signo
);
3627 if (errno
!= ENOSYS
)
3634 return kill (lwpid
, signo
);
3638 linux_stop_lwp (struct lwp_info
*lwp
)
3644 send_sigstop (struct lwp_info
*lwp
)
3648 pid
= lwpid_of (get_lwp_thread (lwp
));
3650 /* If we already have a pending stop signal for this process, don't
3652 if (lwp
->stop_expected
)
3655 debug_printf ("Have pending sigstop for lwp %d\n", pid
);
3661 debug_printf ("Sending sigstop to lwp %d\n", pid
);
3663 lwp
->stop_expected
= 1;
3664 kill_lwp (pid
, SIGSTOP
);
3668 send_sigstop_callback (struct inferior_list_entry
*entry
, void *except
)
3670 struct thread_info
*thread
= (struct thread_info
*) entry
;
3671 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3673 /* Ignore EXCEPT. */
3684 /* Increment the suspend count of an LWP, and stop it, if not stopped
3687 suspend_and_send_sigstop_callback (struct inferior_list_entry
*entry
,
3690 struct thread_info
*thread
= (struct thread_info
*) entry
;
3691 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3693 /* Ignore EXCEPT. */
3697 lwp_suspended_inc (lwp
);
3699 return send_sigstop_callback (entry
, except
);
3703 mark_lwp_dead (struct lwp_info
*lwp
, int wstat
)
3705 /* Store the exit status for later. */
3706 lwp
->status_pending_p
= 1;
3707 lwp
->status_pending
= wstat
;
3709 /* Store in waitstatus as well, as there's nothing else to process
3711 if (WIFEXITED (wstat
))
3713 lwp
->waitstatus
.kind
= TARGET_WAITKIND_EXITED
;
3714 lwp
->waitstatus
.value
.integer
= WEXITSTATUS (wstat
);
3716 else if (WIFSIGNALED (wstat
))
3718 lwp
->waitstatus
.kind
= TARGET_WAITKIND_SIGNALLED
;
3719 lwp
->waitstatus
.value
.sig
= gdb_signal_from_host (WTERMSIG (wstat
));
3722 /* Prevent trying to stop it. */
3725 /* No further stops are expected from a dead lwp. */
3726 lwp
->stop_expected
= 0;
3729 /* Return true if LWP has exited already, and has a pending exit event
3730 to report to GDB. */
3733 lwp_is_marked_dead (struct lwp_info
*lwp
)
3735 return (lwp
->status_pending_p
3736 && (WIFEXITED (lwp
->status_pending
)
3737 || WIFSIGNALED (lwp
->status_pending
)));
3740 /* Wait for all children to stop for the SIGSTOPs we just queued. */
3743 wait_for_sigstop (void)
3745 struct thread_info
*saved_thread
;
3750 saved_thread
= current_thread
;
3751 if (saved_thread
!= NULL
)
3752 saved_tid
= saved_thread
->entry
.id
;
3754 saved_tid
= null_ptid
; /* avoid bogus unused warning */
3757 debug_printf ("wait_for_sigstop: pulling events\n");
3759 /* Passing NULL_PTID as filter indicates we want all events to be
3760 left pending. Eventually this returns when there are no
3761 unwaited-for children left. */
3762 ret
= linux_wait_for_event_filtered (minus_one_ptid
, null_ptid
,
3764 gdb_assert (ret
== -1);
3766 if (saved_thread
== NULL
|| linux_thread_alive (saved_tid
))
3767 current_thread
= saved_thread
;
3771 debug_printf ("Previously current thread died.\n");
3773 /* We can't change the current inferior behind GDB's back,
3774 otherwise, a subsequent command may apply to the wrong
3776 current_thread
= NULL
;
3780 /* Returns true if LWP ENTRY is stopped in a jump pad, and we can't
3781 move it out, because we need to report the stop event to GDB. For
3782 example, if the user puts a breakpoint in the jump pad, it's
3783 because she wants to debug it. */
3786 stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
, void *data
)
3788 struct thread_info
*thread
= (struct thread_info
*) entry
;
3789 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3791 if (lwp
->suspended
!= 0)
3793 internal_error (__FILE__
, __LINE__
,
3794 "LWP %ld is suspended, suspended=%d\n",
3795 lwpid_of (thread
), lwp
->suspended
);
3797 gdb_assert (lwp
->stopped
);
3799 /* Allow debugging the jump pad, gdb_collect, etc.. */
3800 return (supports_fast_tracepoints ()
3801 && agent_loaded_p ()
3802 && (gdb_breakpoint_here (lwp
->stop_pc
)
3803 || lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
3804 || thread
->last_resume_kind
== resume_step
)
3805 && linux_fast_tracepoint_collecting (lwp
, NULL
));
3809 move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
)
3811 struct thread_info
*thread
= (struct thread_info
*) entry
;
3812 struct thread_info
*saved_thread
;
3813 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3816 if (lwp
->suspended
!= 0)
3818 internal_error (__FILE__
, __LINE__
,
3819 "LWP %ld is suspended, suspended=%d\n",
3820 lwpid_of (thread
), lwp
->suspended
);
3822 gdb_assert (lwp
->stopped
);
3824 /* For gdb_breakpoint_here. */
3825 saved_thread
= current_thread
;
3826 current_thread
= thread
;
3828 wstat
= lwp
->status_pending_p
? &lwp
->status_pending
: NULL
;
3830 /* Allow debugging the jump pad, gdb_collect, etc. */
3831 if (!gdb_breakpoint_here (lwp
->stop_pc
)
3832 && lwp
->stop_reason
!= TARGET_STOPPED_BY_WATCHPOINT
3833 && thread
->last_resume_kind
!= resume_step
3834 && maybe_move_out_of_jump_pad (lwp
, wstat
))
3837 debug_printf ("LWP %ld needs stabilizing (in jump pad)\n",
3842 lwp
->status_pending_p
= 0;
3843 enqueue_one_deferred_signal (lwp
, wstat
);
3846 debug_printf ("Signal %d for LWP %ld deferred "
3848 WSTOPSIG (*wstat
), lwpid_of (thread
));
3851 linux_resume_one_lwp (lwp
, 0, 0, NULL
);
3854 lwp_suspended_inc (lwp
);
3856 current_thread
= saved_thread
;
3860 lwp_running (struct inferior_list_entry
*entry
, void *data
)
3862 struct thread_info
*thread
= (struct thread_info
*) entry
;
3863 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3865 if (lwp_is_marked_dead (lwp
))
3872 /* Stop all lwps that aren't stopped yet, except EXCEPT, if not NULL.
3873 If SUSPEND, then also increase the suspend count of every LWP,
3877 stop_all_lwps (int suspend
, struct lwp_info
*except
)
3879 /* Should not be called recursively. */
3880 gdb_assert (stopping_threads
== NOT_STOPPING_THREADS
);
3885 debug_printf ("stop_all_lwps (%s, except=%s)\n",
3886 suspend
? "stop-and-suspend" : "stop",
3888 ? target_pid_to_str (ptid_of (get_lwp_thread (except
)))
3892 stopping_threads
= (suspend
3893 ? STOPPING_AND_SUSPENDING_THREADS
3894 : STOPPING_THREADS
);
3897 find_inferior (&all_threads
, suspend_and_send_sigstop_callback
, except
);
3899 find_inferior (&all_threads
, send_sigstop_callback
, except
);
3900 wait_for_sigstop ();
3901 stopping_threads
= NOT_STOPPING_THREADS
;
3905 debug_printf ("stop_all_lwps done, setting stopping_threads "
3906 "back to !stopping\n");
3911 /* Enqueue one signal in the chain of signals which need to be
3912 delivered to this process on next resume. */
3915 enqueue_pending_signal (struct lwp_info
*lwp
, int signal
, siginfo_t
*info
)
3917 struct pending_signals
*p_sig
= XNEW (struct pending_signals
);
3919 p_sig
->prev
= lwp
->pending_signals
;
3920 p_sig
->signal
= signal
;
3922 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
3924 memcpy (&p_sig
->info
, info
, sizeof (siginfo_t
));
3925 lwp
->pending_signals
= p_sig
;
3928 /* Resume execution of LWP. If STEP is nonzero, single-step it. If
3929 SIGNAL is nonzero, give it that signal. */
3932 linux_resume_one_lwp_throw (struct lwp_info
*lwp
,
3933 int step
, int signal
, siginfo_t
*info
)
3935 struct thread_info
*thread
= get_lwp_thread (lwp
);
3936 struct thread_info
*saved_thread
;
3937 int fast_tp_collecting
;
3938 struct process_info
*proc
= get_thread_process (thread
);
3940 /* Note that target description may not be initialised
3941 (proc->tdesc == NULL) at this point because the program hasn't
3942 stopped at the first instruction yet. It means GDBserver skips
3943 the extra traps from the wrapper program (see option --wrapper).
3944 Code in this function that requires register access should be
3945 guarded by proc->tdesc == NULL or something else. */
3947 if (lwp
->stopped
== 0)
3950 gdb_assert (lwp
->waitstatus
.kind
== TARGET_WAITKIND_IGNORE
);
3952 fast_tp_collecting
= lwp
->collecting_fast_tracepoint
;
3954 gdb_assert (!stabilizing_threads
|| fast_tp_collecting
);
3956 /* Cancel actions that rely on GDB not changing the PC (e.g., the
3957 user used the "jump" command, or "set $pc = foo"). */
3958 if (thread
->while_stepping
!= NULL
&& lwp
->stop_pc
!= get_pc (lwp
))
3960 /* Collecting 'while-stepping' actions doesn't make sense
3962 release_while_stepping_state_list (thread
);
3965 /* If we have pending signals or status, and a new signal, enqueue the
3966 signal. Also enqueue the signal if we are waiting to reinsert a
3967 breakpoint; it will be picked up again below. */
3969 && (lwp
->status_pending_p
3970 || lwp
->pending_signals
!= NULL
3971 || lwp
->bp_reinsert
!= 0
3972 || fast_tp_collecting
))
3974 struct pending_signals
*p_sig
= XNEW (struct pending_signals
);
3976 p_sig
->prev
= lwp
->pending_signals
;
3977 p_sig
->signal
= signal
;
3979 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
3981 memcpy (&p_sig
->info
, info
, sizeof (siginfo_t
));
3982 lwp
->pending_signals
= p_sig
;
3985 if (lwp
->status_pending_p
)
3988 debug_printf ("Not resuming lwp %ld (%s, signal %d, stop %s);"
3989 " has pending status\n",
3990 lwpid_of (thread
), step
? "step" : "continue", signal
,
3991 lwp
->stop_expected
? "expected" : "not expected");
3995 saved_thread
= current_thread
;
3996 current_thread
= thread
;
3999 debug_printf ("Resuming lwp %ld (%s, signal %d, stop %s)\n",
4000 lwpid_of (thread
), step
? "step" : "continue", signal
,
4001 lwp
->stop_expected
? "expected" : "not expected");
4003 /* This bit needs some thinking about. If we get a signal that
4004 we must report while a single-step reinsert is still pending,
4005 we often end up resuming the thread. It might be better to
4006 (ew) allow a stack of pending events; then we could be sure that
4007 the reinsert happened right away and not lose any signals.
4009 Making this stack would also shrink the window in which breakpoints are
4010 uninserted (see comment in linux_wait_for_lwp) but not enough for
4011 complete correctness, so it won't solve that problem. It may be
4012 worthwhile just to solve this one, however. */
4013 if (lwp
->bp_reinsert
!= 0)
4016 debug_printf (" pending reinsert at 0x%s\n",
4017 paddress (lwp
->bp_reinsert
));
4019 if (can_hardware_single_step ())
4021 if (fast_tp_collecting
== 0)
4024 fprintf (stderr
, "BAD - reinserting but not stepping.\n");
4026 fprintf (stderr
, "BAD - reinserting and suspended(%d).\n",
4033 /* Postpone any pending signal. It was enqueued above. */
4037 if (fast_tp_collecting
== 1)
4040 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
4041 " (exit-jump-pad-bkpt)\n",
4044 /* Postpone any pending signal. It was enqueued above. */
4047 else if (fast_tp_collecting
== 2)
4050 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
4051 " single-stepping\n",
4054 if (can_hardware_single_step ())
4058 internal_error (__FILE__
, __LINE__
,
4059 "moving out of jump pad single-stepping"
4060 " not implemented on this target");
4063 /* Postpone any pending signal. It was enqueued above. */
4067 /* If we have while-stepping actions in this thread set it stepping.
4068 If we have a signal to deliver, it may or may not be set to
4069 SIG_IGN, we don't know. Assume so, and allow collecting
4070 while-stepping into a signal handler. A possible smart thing to
4071 do would be to set an internal breakpoint at the signal return
4072 address, continue, and carry on catching this while-stepping
4073 action only when that breakpoint is hit. A future
4075 if (thread
->while_stepping
!= NULL
4076 && can_hardware_single_step ())
4079 debug_printf ("lwp %ld has a while-stepping action -> forcing step.\n",
4084 if (proc
->tdesc
!= NULL
&& the_low_target
.get_pc
!= NULL
)
4086 struct regcache
*regcache
= get_thread_regcache (current_thread
, 1);
4088 lwp
->stop_pc
= (*the_low_target
.get_pc
) (regcache
);
4092 debug_printf (" %s from pc 0x%lx\n", step
? "step" : "continue",
4093 (long) lwp
->stop_pc
);
4097 /* If we have pending signals, consume one unless we are trying to
4098 reinsert a breakpoint or we're trying to finish a fast tracepoint
4100 if (lwp
->pending_signals
!= NULL
4101 && lwp
->bp_reinsert
== 0
4102 && fast_tp_collecting
== 0)
4104 struct pending_signals
**p_sig
;
4106 p_sig
= &lwp
->pending_signals
;
4107 while ((*p_sig
)->prev
!= NULL
)
4108 p_sig
= &(*p_sig
)->prev
;
4110 signal
= (*p_sig
)->signal
;
4111 if ((*p_sig
)->info
.si_signo
!= 0)
4112 ptrace (PTRACE_SETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
4119 if (the_low_target
.prepare_to_resume
!= NULL
)
4120 the_low_target
.prepare_to_resume (lwp
);
4122 regcache_invalidate_thread (thread
);
4124 lwp
->stepping
= step
;
4125 ptrace (step
? PTRACE_SINGLESTEP
: PTRACE_CONT
, lwpid_of (thread
),
4126 (PTRACE_TYPE_ARG3
) 0,
4127 /* Coerce to a uintptr_t first to avoid potential gcc warning
4128 of coercing an 8 byte integer to a 4 byte pointer. */
4129 (PTRACE_TYPE_ARG4
) (uintptr_t) signal
);
4131 current_thread
= saved_thread
;
4133 perror_with_name ("resuming thread");
4135 /* Successfully resumed. Clear state that no longer makes sense,
4136 and mark the LWP as running. Must not do this before resuming
4137 otherwise if that fails other code will be confused. E.g., we'd
4138 later try to stop the LWP and hang forever waiting for a stop
4139 status. Note that we must not throw after this is cleared,
4140 otherwise handle_zombie_lwp_error would get confused. */
4142 lwp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
4145 /* Called when we try to resume a stopped LWP and that errors out. If
4146 the LWP is no longer in ptrace-stopped state (meaning it's zombie,
4147 or about to become), discard the error, clear any pending status
4148 the LWP may have, and return true (we'll collect the exit status
4149 soon enough). Otherwise, return false. */
4152 check_ptrace_stopped_lwp_gone (struct lwp_info
*lp
)
4154 struct thread_info
*thread
= get_lwp_thread (lp
);
4156 /* If we get an error after resuming the LWP successfully, we'd
4157 confuse !T state for the LWP being gone. */
4158 gdb_assert (lp
->stopped
);
4160 /* We can't just check whether the LWP is in 'Z (Zombie)' state,
4161 because even if ptrace failed with ESRCH, the tracee may be "not
4162 yet fully dead", but already refusing ptrace requests. In that
4163 case the tracee has 'R (Running)' state for a little bit
4164 (observed in Linux 3.18). See also the note on ESRCH in the
4165 ptrace(2) man page. Instead, check whether the LWP has any state
4166 other than ptrace-stopped. */
4168 /* Don't assume anything if /proc/PID/status can't be read. */
4169 if (linux_proc_pid_is_trace_stopped_nowarn (lwpid_of (thread
)) == 0)
4171 lp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
4172 lp
->status_pending_p
= 0;
4178 /* Like linux_resume_one_lwp_throw, but no error is thrown if the LWP
4179 disappears while we try to resume it. */
4182 linux_resume_one_lwp (struct lwp_info
*lwp
,
4183 int step
, int signal
, siginfo_t
*info
)
4187 linux_resume_one_lwp_throw (lwp
, step
, signal
, info
);
4189 CATCH (ex
, RETURN_MASK_ERROR
)
4191 if (!check_ptrace_stopped_lwp_gone (lwp
))
4192 throw_exception (ex
);
4197 struct thread_resume_array
4199 struct thread_resume
*resume
;
4203 /* This function is called once per thread via find_inferior.
4204 ARG is a pointer to a thread_resume_array struct.
4205 We look up the thread specified by ENTRY in ARG, and mark the thread
4206 with a pointer to the appropriate resume request.
4208 This algorithm is O(threads * resume elements), but resume elements
4209 is small (and will remain small at least until GDB supports thread
4213 linux_set_resume_request (struct inferior_list_entry
*entry
, void *arg
)
4215 struct thread_info
*thread
= (struct thread_info
*) entry
;
4216 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4218 struct thread_resume_array
*r
;
4220 r
= (struct thread_resume_array
*) arg
;
4222 for (ndx
= 0; ndx
< r
->n
; ndx
++)
4224 ptid_t ptid
= r
->resume
[ndx
].thread
;
4225 if (ptid_equal (ptid
, minus_one_ptid
)
4226 || ptid_equal (ptid
, entry
->id
)
4227 /* Handle both 'pPID' and 'pPID.-1' as meaning 'all threads
4229 || (ptid_get_pid (ptid
) == pid_of (thread
)
4230 && (ptid_is_pid (ptid
)
4231 || ptid_get_lwp (ptid
) == -1)))
4233 if (r
->resume
[ndx
].kind
== resume_stop
4234 && thread
->last_resume_kind
== resume_stop
)
4237 debug_printf ("already %s LWP %ld at GDB's request\n",
4238 (thread
->last_status
.kind
4239 == TARGET_WAITKIND_STOPPED
)
4247 lwp
->resume
= &r
->resume
[ndx
];
4248 thread
->last_resume_kind
= lwp
->resume
->kind
;
4250 lwp
->step_range_start
= lwp
->resume
->step_range_start
;
4251 lwp
->step_range_end
= lwp
->resume
->step_range_end
;
4253 /* If we had a deferred signal to report, dequeue one now.
4254 This can happen if LWP gets more than one signal while
4255 trying to get out of a jump pad. */
4257 && !lwp
->status_pending_p
4258 && dequeue_one_deferred_signal (lwp
, &lwp
->status_pending
))
4260 lwp
->status_pending_p
= 1;
4263 debug_printf ("Dequeueing deferred signal %d for LWP %ld, "
4264 "leaving status pending.\n",
4265 WSTOPSIG (lwp
->status_pending
),
4273 /* No resume action for this thread. */
4279 /* find_inferior callback for linux_resume.
4280 Set *FLAG_P if this lwp has an interesting status pending. */
4283 resume_status_pending_p (struct inferior_list_entry
*entry
, void *flag_p
)
4285 struct thread_info
*thread
= (struct thread_info
*) entry
;
4286 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4288 /* LWPs which will not be resumed are not interesting, because
4289 we might not wait for them next time through linux_wait. */
4290 if (lwp
->resume
== NULL
)
4293 if (thread_still_has_status_pending_p (thread
))
4294 * (int *) flag_p
= 1;
4299 /* Return 1 if this lwp that GDB wants running is stopped at an
4300 internal breakpoint that we need to step over. It assumes that any
4301 required STOP_PC adjustment has already been propagated to the
4302 inferior's regcache. */
4305 need_step_over_p (struct inferior_list_entry
*entry
, void *dummy
)
4307 struct thread_info
*thread
= (struct thread_info
*) entry
;
4308 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4309 struct thread_info
*saved_thread
;
4311 struct process_info
*proc
= get_thread_process (thread
);
4313 /* GDBserver is skipping the extra traps from the wrapper program,
4314 don't have to do step over. */
4315 if (proc
->tdesc
== NULL
)
4318 /* LWPs which will not be resumed are not interesting, because we
4319 might not wait for them next time through linux_wait. */
4324 debug_printf ("Need step over [LWP %ld]? Ignoring, not stopped\n",
4329 if (thread
->last_resume_kind
== resume_stop
)
4332 debug_printf ("Need step over [LWP %ld]? Ignoring, should remain"
4338 gdb_assert (lwp
->suspended
>= 0);
4343 debug_printf ("Need step over [LWP %ld]? Ignoring, suspended\n",
4348 if (!lwp
->need_step_over
)
4351 debug_printf ("Need step over [LWP %ld]? No\n", lwpid_of (thread
));
4354 if (lwp
->status_pending_p
)
4357 debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
4363 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
4367 /* If the PC has changed since we stopped, then don't do anything,
4368 and let the breakpoint/tracepoint be hit. This happens if, for
4369 instance, GDB handled the decr_pc_after_break subtraction itself,
4370 GDB is OOL stepping this thread, or the user has issued a "jump"
4371 command, or poked thread's registers herself. */
4372 if (pc
!= lwp
->stop_pc
)
4375 debug_printf ("Need step over [LWP %ld]? Cancelling, PC was changed. "
4376 "Old stop_pc was 0x%s, PC is now 0x%s\n",
4378 paddress (lwp
->stop_pc
), paddress (pc
));
4380 lwp
->need_step_over
= 0;
4384 saved_thread
= current_thread
;
4385 current_thread
= thread
;
4387 /* We can only step over breakpoints we know about. */
4388 if (breakpoint_here (pc
) || fast_tracepoint_jump_here (pc
))
4390 /* Don't step over a breakpoint that GDB expects to hit
4391 though. If the condition is being evaluated on the target's side
4392 and it evaluate to false, step over this breakpoint as well. */
4393 if (gdb_breakpoint_here (pc
)
4394 && gdb_condition_true_at_breakpoint (pc
)
4395 && gdb_no_commands_at_breakpoint (pc
))
4398 debug_printf ("Need step over [LWP %ld]? yes, but found"
4399 " GDB breakpoint at 0x%s; skipping step over\n",
4400 lwpid_of (thread
), paddress (pc
));
4402 current_thread
= saved_thread
;
4408 debug_printf ("Need step over [LWP %ld]? yes, "
4409 "found breakpoint at 0x%s\n",
4410 lwpid_of (thread
), paddress (pc
));
4412 /* We've found an lwp that needs stepping over --- return 1 so
4413 that find_inferior stops looking. */
4414 current_thread
= saved_thread
;
4416 /* If the step over is cancelled, this is set again. */
4417 lwp
->need_step_over
= 0;
4422 current_thread
= saved_thread
;
4425 debug_printf ("Need step over [LWP %ld]? No, no breakpoint found"
4427 lwpid_of (thread
), paddress (pc
));
4432 /* Start a step-over operation on LWP. When LWP stopped at a
4433 breakpoint, to make progress, we need to remove the breakpoint out
4434 of the way. If we let other threads run while we do that, they may
4435 pass by the breakpoint location and miss hitting it. To avoid
4436 that, a step-over momentarily stops all threads while LWP is
4437 single-stepped while the breakpoint is temporarily uninserted from
4438 the inferior. When the single-step finishes, we reinsert the
4439 breakpoint, and let all threads that are supposed to be running,
4442 On targets that don't support hardware single-step, we don't
4443 currently support full software single-stepping. Instead, we only
4444 support stepping over the thread event breakpoint, by asking the
4445 low target where to place a reinsert breakpoint. Since this
4446 routine assumes the breakpoint being stepped over is a thread event
4447 breakpoint, it usually assumes the return address of the current
4448 function is a good enough place to set the reinsert breakpoint. */
4451 start_step_over (struct lwp_info
*lwp
)
4453 struct thread_info
*thread
= get_lwp_thread (lwp
);
4454 struct thread_info
*saved_thread
;
4459 debug_printf ("Starting step-over on LWP %ld. Stopping all threads\n",
4462 stop_all_lwps (1, lwp
);
4464 if (lwp
->suspended
!= 0)
4466 internal_error (__FILE__
, __LINE__
,
4467 "LWP %ld suspended=%d\n", lwpid_of (thread
),
4472 debug_printf ("Done stopping all threads for step-over.\n");
4474 /* Note, we should always reach here with an already adjusted PC,
4475 either by GDB (if we're resuming due to GDB's request), or by our
4476 caller, if we just finished handling an internal breakpoint GDB
4477 shouldn't care about. */
4480 saved_thread
= current_thread
;
4481 current_thread
= thread
;
4483 lwp
->bp_reinsert
= pc
;
4484 uninsert_breakpoints_at (pc
);
4485 uninsert_fast_tracepoint_jumps_at (pc
);
4487 if (can_hardware_single_step ())
4493 CORE_ADDR raddr
= (*the_low_target
.breakpoint_reinsert_addr
) ();
4494 set_reinsert_breakpoint (raddr
);
4498 current_thread
= saved_thread
;
4500 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
4502 /* Require next event from this LWP. */
4503 step_over_bkpt
= thread
->entry
.id
;
4507 /* Finish a step-over. Reinsert the breakpoint we had uninserted in
4508 start_step_over, if still there, and delete any reinsert
4509 breakpoints we've set, on non hardware single-step targets. */
4512 finish_step_over (struct lwp_info
*lwp
)
4514 if (lwp
->bp_reinsert
!= 0)
4517 debug_printf ("Finished step over.\n");
4519 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
4520 may be no breakpoint to reinsert there by now. */
4521 reinsert_breakpoints_at (lwp
->bp_reinsert
);
4522 reinsert_fast_tracepoint_jumps_at (lwp
->bp_reinsert
);
4524 lwp
->bp_reinsert
= 0;
4526 /* Delete any software-single-step reinsert breakpoints. No
4527 longer needed. We don't have to worry about other threads
4528 hitting this trap, and later not being able to explain it,
4529 because we were stepping over a breakpoint, and we hold all
4530 threads but LWP stopped while doing that. */
4531 if (!can_hardware_single_step ())
4532 delete_reinsert_breakpoints ();
4534 step_over_bkpt
= null_ptid
;
4541 /* If there's a step over in progress, wait until all threads stop
4542 (that is, until the stepping thread finishes its step), and
4543 unsuspend all lwps. The stepping thread ends with its status
4544 pending, which is processed later when we get back to processing
4548 complete_ongoing_step_over (void)
4550 if (!ptid_equal (step_over_bkpt
, null_ptid
))
4552 struct lwp_info
*lwp
;
4557 debug_printf ("detach: step over in progress, finish it first\n");
4559 /* Passing NULL_PTID as filter indicates we want all events to
4560 be left pending. Eventually this returns when there are no
4561 unwaited-for children left. */
4562 ret
= linux_wait_for_event_filtered (minus_one_ptid
, null_ptid
,
4564 gdb_assert (ret
== -1);
4566 lwp
= find_lwp_pid (step_over_bkpt
);
4568 finish_step_over (lwp
);
4569 step_over_bkpt
= null_ptid
;
4570 unsuspend_all_lwps (lwp
);
4574 /* This function is called once per thread. We check the thread's resume
4575 request, which will tell us whether to resume, step, or leave the thread
4576 stopped; and what signal, if any, it should be sent.
4578 For threads which we aren't explicitly told otherwise, we preserve
4579 the stepping flag; this is used for stepping over gdbserver-placed
4582 If pending_flags was set in any thread, we queue any needed
4583 signals, since we won't actually resume. We already have a pending
4584 event to report, so we don't need to preserve any step requests;
4585 they should be re-issued if necessary. */
4588 linux_resume_one_thread (struct inferior_list_entry
*entry
, void *arg
)
4590 struct thread_info
*thread
= (struct thread_info
*) entry
;
4591 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4593 int leave_all_stopped
= * (int *) arg
;
4596 if (lwp
->resume
== NULL
)
4599 if (lwp
->resume
->kind
== resume_stop
)
4602 debug_printf ("resume_stop request for LWP %ld\n", lwpid_of (thread
));
4607 debug_printf ("stopping LWP %ld\n", lwpid_of (thread
));
4609 /* Stop the thread, and wait for the event asynchronously,
4610 through the event loop. */
4616 debug_printf ("already stopped LWP %ld\n",
4619 /* The LWP may have been stopped in an internal event that
4620 was not meant to be notified back to GDB (e.g., gdbserver
4621 breakpoint), so we should be reporting a stop event in
4624 /* If the thread already has a pending SIGSTOP, this is a
4625 no-op. Otherwise, something later will presumably resume
4626 the thread and this will cause it to cancel any pending
4627 operation, due to last_resume_kind == resume_stop. If
4628 the thread already has a pending status to report, we
4629 will still report it the next time we wait - see
4630 status_pending_p_callback. */
4632 /* If we already have a pending signal to report, then
4633 there's no need to queue a SIGSTOP, as this means we're
4634 midway through moving the LWP out of the jumppad, and we
4635 will report the pending signal as soon as that is
4637 if (lwp
->pending_signals_to_report
== NULL
)
4641 /* For stop requests, we're done. */
4643 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
4647 /* If this thread which is about to be resumed has a pending status,
4648 then don't resume it - we can just report the pending status.
4649 Likewise if it is suspended, because e.g., another thread is
4650 stepping past a breakpoint. Make sure to queue any signals that
4651 would otherwise be sent. In all-stop mode, we do this decision
4652 based on if *any* thread has a pending status. If there's a
4653 thread that needs the step-over-breakpoint dance, then don't
4654 resume any other thread but that particular one. */
4655 leave_pending
= (lwp
->suspended
4656 || lwp
->status_pending_p
4657 || leave_all_stopped
);
4662 debug_printf ("resuming LWP %ld\n", lwpid_of (thread
));
4664 step
= (lwp
->resume
->kind
== resume_step
);
4665 linux_resume_one_lwp (lwp
, step
, lwp
->resume
->sig
, NULL
);
4670 debug_printf ("leaving LWP %ld stopped\n", lwpid_of (thread
));
4672 /* If we have a new signal, enqueue the signal. */
4673 if (lwp
->resume
->sig
!= 0)
4675 struct pending_signals
*p_sig
= XCNEW (struct pending_signals
);
4677 p_sig
->prev
= lwp
->pending_signals
;
4678 p_sig
->signal
= lwp
->resume
->sig
;
4680 /* If this is the same signal we were previously stopped by,
4681 make sure to queue its siginfo. We can ignore the return
4682 value of ptrace; if it fails, we'll skip
4683 PTRACE_SETSIGINFO. */
4684 if (WIFSTOPPED (lwp
->last_status
)
4685 && WSTOPSIG (lwp
->last_status
) == lwp
->resume
->sig
)
4686 ptrace (PTRACE_GETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
4689 lwp
->pending_signals
= p_sig
;
4693 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
4699 linux_resume (struct thread_resume
*resume_info
, size_t n
)
4701 struct thread_resume_array array
= { resume_info
, n
};
4702 struct thread_info
*need_step_over
= NULL
;
4704 int leave_all_stopped
;
4709 debug_printf ("linux_resume:\n");
4712 find_inferior (&all_threads
, linux_set_resume_request
, &array
);
4714 /* If there is a thread which would otherwise be resumed, which has
4715 a pending status, then don't resume any threads - we can just
4716 report the pending status. Make sure to queue any signals that
4717 would otherwise be sent. In non-stop mode, we'll apply this
4718 logic to each thread individually. We consume all pending events
4719 before considering to start a step-over (in all-stop). */
4722 find_inferior (&all_threads
, resume_status_pending_p
, &any_pending
);
4724 /* If there is a thread which would otherwise be resumed, which is
4725 stopped at a breakpoint that needs stepping over, then don't
4726 resume any threads - have it step over the breakpoint with all
4727 other threads stopped, then resume all threads again. Make sure
4728 to queue any signals that would otherwise be delivered or
4730 if (!any_pending
&& supports_breakpoints ())
4732 = (struct thread_info
*) find_inferior (&all_threads
,
4733 need_step_over_p
, NULL
);
4735 leave_all_stopped
= (need_step_over
!= NULL
|| any_pending
);
4739 if (need_step_over
!= NULL
)
4740 debug_printf ("Not resuming all, need step over\n");
4741 else if (any_pending
)
4742 debug_printf ("Not resuming, all-stop and found "
4743 "an LWP with pending status\n");
4745 debug_printf ("Resuming, no pending status or step over needed\n");
4748 /* Even if we're leaving threads stopped, queue all signals we'd
4749 otherwise deliver. */
4750 find_inferior (&all_threads
, linux_resume_one_thread
, &leave_all_stopped
);
4753 start_step_over (get_thread_lwp (need_step_over
));
4757 debug_printf ("linux_resume done\n");
4762 /* This function is called once per thread. We check the thread's
4763 last resume request, which will tell us whether to resume, step, or
4764 leave the thread stopped. Any signal the client requested to be
4765 delivered has already been enqueued at this point.
4767 If any thread that GDB wants running is stopped at an internal
4768 breakpoint that needs stepping over, we start a step-over operation
4769 on that particular thread, and leave all others stopped. */
4772 proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
4774 struct thread_info
*thread
= (struct thread_info
*) entry
;
4775 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4782 debug_printf ("proceed_one_lwp: lwp %ld\n", lwpid_of (thread
));
4787 debug_printf (" LWP %ld already running\n", lwpid_of (thread
));
4791 if (thread
->last_resume_kind
== resume_stop
4792 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
4795 debug_printf (" client wants LWP to remain %ld stopped\n",
4800 if (lwp
->status_pending_p
)
4803 debug_printf (" LWP %ld has pending status, leaving stopped\n",
4808 gdb_assert (lwp
->suspended
>= 0);
4813 debug_printf (" LWP %ld is suspended\n", lwpid_of (thread
));
4817 if (thread
->last_resume_kind
== resume_stop
4818 && lwp
->pending_signals_to_report
== NULL
4819 && lwp
->collecting_fast_tracepoint
== 0)
4821 /* We haven't reported this LWP as stopped yet (otherwise, the
4822 last_status.kind check above would catch it, and we wouldn't
4823 reach here. This LWP may have been momentarily paused by a
4824 stop_all_lwps call while handling for example, another LWP's
4825 step-over. In that case, the pending expected SIGSTOP signal
4826 that was queued at vCont;t handling time will have already
4827 been consumed by wait_for_sigstop, and so we need to requeue
4828 another one here. Note that if the LWP already has a SIGSTOP
4829 pending, this is a no-op. */
4832 debug_printf ("Client wants LWP %ld to stop. "
4833 "Making sure it has a SIGSTOP pending\n",
4839 if (thread
->last_resume_kind
== resume_step
)
4842 debug_printf (" stepping LWP %ld, client wants it stepping\n",
4846 else if (lwp
->bp_reinsert
!= 0)
4849 debug_printf (" stepping LWP %ld, reinsert set\n",
4856 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
4861 unsuspend_and_proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
4863 struct thread_info
*thread
= (struct thread_info
*) entry
;
4864 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4869 lwp_suspended_decr (lwp
);
4871 return proceed_one_lwp (entry
, except
);
4874 /* When we finish a step-over, set threads running again. If there's
4875 another thread that may need a step-over, now's the time to start
4876 it. Eventually, we'll move all threads past their breakpoints. */
4879 proceed_all_lwps (void)
4881 struct thread_info
*need_step_over
;
4883 /* If there is a thread which would otherwise be resumed, which is
4884 stopped at a breakpoint that needs stepping over, then don't
4885 resume any threads - have it step over the breakpoint with all
4886 other threads stopped, then resume all threads again. */
4888 if (supports_breakpoints ())
4891 = (struct thread_info
*) find_inferior (&all_threads
,
4892 need_step_over_p
, NULL
);
4894 if (need_step_over
!= NULL
)
4897 debug_printf ("proceed_all_lwps: found "
4898 "thread %ld needing a step-over\n",
4899 lwpid_of (need_step_over
));
4901 start_step_over (get_thread_lwp (need_step_over
));
4907 debug_printf ("Proceeding, no step-over needed\n");
4909 find_inferior (&all_threads
, proceed_one_lwp
, NULL
);
4912 /* Stopped LWPs that the client wanted to be running, that don't have
4913 pending statuses, are set to run again, except for EXCEPT, if not
4914 NULL. This undoes a stop_all_lwps call. */
4917 unstop_all_lwps (int unsuspend
, struct lwp_info
*except
)
4923 debug_printf ("unstopping all lwps, except=(LWP %ld)\n",
4924 lwpid_of (get_lwp_thread (except
)));
4926 debug_printf ("unstopping all lwps\n");
4930 find_inferior (&all_threads
, unsuspend_and_proceed_one_lwp
, except
);
4932 find_inferior (&all_threads
, proceed_one_lwp
, except
);
4936 debug_printf ("unstop_all_lwps done\n");
4942 #ifdef HAVE_LINUX_REGSETS
4944 #define use_linux_regsets 1
4946 /* Returns true if REGSET has been disabled. */
4949 regset_disabled (struct regsets_info
*info
, struct regset_info
*regset
)
4951 return (info
->disabled_regsets
!= NULL
4952 && info
->disabled_regsets
[regset
- info
->regsets
]);
4955 /* Disable REGSET. */
4958 disable_regset (struct regsets_info
*info
, struct regset_info
*regset
)
4962 dr_offset
= regset
- info
->regsets
;
4963 if (info
->disabled_regsets
== NULL
)
4964 info
->disabled_regsets
= (char *) xcalloc (1, info
->num_regsets
);
4965 info
->disabled_regsets
[dr_offset
] = 1;
4969 regsets_fetch_inferior_registers (struct regsets_info
*regsets_info
,
4970 struct regcache
*regcache
)
4972 struct regset_info
*regset
;
4973 int saw_general_regs
= 0;
4977 pid
= lwpid_of (current_thread
);
4978 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
4983 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
))
4986 buf
= xmalloc (regset
->size
);
4988 nt_type
= regset
->nt_type
;
4992 iov
.iov_len
= regset
->size
;
4993 data
= (void *) &iov
;
4999 res
= ptrace (regset
->get_request
, pid
,
5000 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5002 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
5008 /* If we get EIO on a regset, do not try it again for
5009 this process mode. */
5010 disable_regset (regsets_info
, regset
);
5012 else if (errno
== ENODATA
)
5014 /* ENODATA may be returned if the regset is currently
5015 not "active". This can happen in normal operation,
5016 so suppress the warning in this case. */
5021 sprintf (s
, "ptrace(regsets_fetch_inferior_registers) PID=%d",
5028 if (regset
->type
== GENERAL_REGS
)
5029 saw_general_regs
= 1;
5030 regset
->store_function (regcache
, buf
);
5034 if (saw_general_regs
)
5041 regsets_store_inferior_registers (struct regsets_info
*regsets_info
,
5042 struct regcache
*regcache
)
5044 struct regset_info
*regset
;
5045 int saw_general_regs
= 0;
5049 pid
= lwpid_of (current_thread
);
5050 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
5055 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
)
5056 || regset
->fill_function
== NULL
)
5059 buf
= xmalloc (regset
->size
);
5061 /* First fill the buffer with the current register set contents,
5062 in case there are any items in the kernel's regset that are
5063 not in gdbserver's regcache. */
5065 nt_type
= regset
->nt_type
;
5069 iov
.iov_len
= regset
->size
;
5070 data
= (void *) &iov
;
5076 res
= ptrace (regset
->get_request
, pid
,
5077 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5079 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
5084 /* Then overlay our cached registers on that. */
5085 regset
->fill_function (regcache
, buf
);
5087 /* Only now do we write the register set. */
5089 res
= ptrace (regset
->set_request
, pid
,
5090 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5092 res
= ptrace (regset
->set_request
, pid
, data
, nt_type
);
5100 /* If we get EIO on a regset, do not try it again for
5101 this process mode. */
5102 disable_regset (regsets_info
, regset
);
5104 else if (errno
== ESRCH
)
5106 /* At this point, ESRCH should mean the process is
5107 already gone, in which case we simply ignore attempts
5108 to change its registers. See also the related
5109 comment in linux_resume_one_lwp. */
5115 perror ("Warning: ptrace(regsets_store_inferior_registers)");
5118 else if (regset
->type
== GENERAL_REGS
)
5119 saw_general_regs
= 1;
5122 if (saw_general_regs
)
5128 #else /* !HAVE_LINUX_REGSETS */
5130 #define use_linux_regsets 0
5131 #define regsets_fetch_inferior_registers(regsets_info, regcache) 1
5132 #define regsets_store_inferior_registers(regsets_info, regcache) 1
5136 /* Return 1 if register REGNO is supported by one of the regset ptrace
5137 calls or 0 if it has to be transferred individually. */
5140 linux_register_in_regsets (const struct regs_info
*regs_info
, int regno
)
5142 unsigned char mask
= 1 << (regno
% 8);
5143 size_t index
= regno
/ 8;
5145 return (use_linux_regsets
5146 && (regs_info
->regset_bitmap
== NULL
5147 || (regs_info
->regset_bitmap
[index
] & mask
) != 0));
5150 #ifdef HAVE_LINUX_USRREGS
5153 register_addr (const struct usrregs_info
*usrregs
, int regnum
)
5157 if (regnum
< 0 || regnum
>= usrregs
->num_regs
)
5158 error ("Invalid register number %d.", regnum
);
5160 addr
= usrregs
->regmap
[regnum
];
5165 /* Fetch one register. */
5167 fetch_register (const struct usrregs_info
*usrregs
,
5168 struct regcache
*regcache
, int regno
)
5175 if (regno
>= usrregs
->num_regs
)
5177 if ((*the_low_target
.cannot_fetch_register
) (regno
))
5180 regaddr
= register_addr (usrregs
, regno
);
5184 size
= ((register_size (regcache
->tdesc
, regno
)
5185 + sizeof (PTRACE_XFER_TYPE
) - 1)
5186 & -sizeof (PTRACE_XFER_TYPE
));
5187 buf
= (char *) alloca (size
);
5189 pid
= lwpid_of (current_thread
);
5190 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
5193 *(PTRACE_XFER_TYPE
*) (buf
+ i
) =
5194 ptrace (PTRACE_PEEKUSER
, pid
,
5195 /* Coerce to a uintptr_t first to avoid potential gcc warning
5196 of coercing an 8 byte integer to a 4 byte pointer. */
5197 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
, (PTRACE_TYPE_ARG4
) 0);
5198 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
5200 error ("reading register %d: %s", regno
, strerror (errno
));
5203 if (the_low_target
.supply_ptrace_register
)
5204 the_low_target
.supply_ptrace_register (regcache
, regno
, buf
);
5206 supply_register (regcache
, regno
, buf
);
5209 /* Store one register. */
5211 store_register (const struct usrregs_info
*usrregs
,
5212 struct regcache
*regcache
, int regno
)
5219 if (regno
>= usrregs
->num_regs
)
5221 if ((*the_low_target
.cannot_store_register
) (regno
))
5224 regaddr
= register_addr (usrregs
, regno
);
5228 size
= ((register_size (regcache
->tdesc
, regno
)
5229 + sizeof (PTRACE_XFER_TYPE
) - 1)
5230 & -sizeof (PTRACE_XFER_TYPE
));
5231 buf
= (char *) alloca (size
);
5232 memset (buf
, 0, size
);
5234 if (the_low_target
.collect_ptrace_register
)
5235 the_low_target
.collect_ptrace_register (regcache
, regno
, buf
);
5237 collect_register (regcache
, regno
, buf
);
5239 pid
= lwpid_of (current_thread
);
5240 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
5243 ptrace (PTRACE_POKEUSER
, pid
,
5244 /* Coerce to a uintptr_t first to avoid potential gcc warning
5245 about coercing an 8 byte integer to a 4 byte pointer. */
5246 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
,
5247 (PTRACE_TYPE_ARG4
) *(PTRACE_XFER_TYPE
*) (buf
+ i
));
5250 /* At this point, ESRCH should mean the process is
5251 already gone, in which case we simply ignore attempts
5252 to change its registers. See also the related
5253 comment in linux_resume_one_lwp. */
5257 if ((*the_low_target
.cannot_store_register
) (regno
) == 0)
5258 error ("writing register %d: %s", regno
, strerror (errno
));
5260 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
5264 /* Fetch all registers, or just one, from the child process.
5265 If REGNO is -1, do this for all registers, skipping any that are
5266 assumed to have been retrieved by regsets_fetch_inferior_registers,
5267 unless ALL is non-zero.
5268 Otherwise, REGNO specifies which register (so we can save time). */
5270 usr_fetch_inferior_registers (const struct regs_info
*regs_info
,
5271 struct regcache
*regcache
, int regno
, int all
)
5273 struct usrregs_info
*usr
= regs_info
->usrregs
;
5277 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
5278 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
5279 fetch_register (usr
, regcache
, regno
);
5282 fetch_register (usr
, regcache
, regno
);
5285 /* Store our register values back into the inferior.
5286 If REGNO is -1, do this for all registers, skipping any that are
5287 assumed to have been saved by regsets_store_inferior_registers,
5288 unless ALL is non-zero.
5289 Otherwise, REGNO specifies which register (so we can save time). */
5291 usr_store_inferior_registers (const struct regs_info
*regs_info
,
5292 struct regcache
*regcache
, int regno
, int all
)
5294 struct usrregs_info
*usr
= regs_info
->usrregs
;
5298 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
5299 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
5300 store_register (usr
, regcache
, regno
);
5303 store_register (usr
, regcache
, regno
);
5306 #else /* !HAVE_LINUX_USRREGS */
5308 #define usr_fetch_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
5309 #define usr_store_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
5315 linux_fetch_registers (struct regcache
*regcache
, int regno
)
5319 const struct regs_info
*regs_info
= (*the_low_target
.regs_info
) ();
5323 if (the_low_target
.fetch_register
!= NULL
5324 && regs_info
->usrregs
!= NULL
)
5325 for (regno
= 0; regno
< regs_info
->usrregs
->num_regs
; regno
++)
5326 (*the_low_target
.fetch_register
) (regcache
, regno
);
5328 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
, regcache
);
5329 if (regs_info
->usrregs
!= NULL
)
5330 usr_fetch_inferior_registers (regs_info
, regcache
, -1, all
);
5334 if (the_low_target
.fetch_register
!= NULL
5335 && (*the_low_target
.fetch_register
) (regcache
, regno
))
5338 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
5340 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
,
5342 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
5343 usr_fetch_inferior_registers (regs_info
, regcache
, regno
, 1);
5348 linux_store_registers (struct regcache
*regcache
, int regno
)
5352 const struct regs_info
*regs_info
= (*the_low_target
.regs_info
) ();
5356 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
5358 if (regs_info
->usrregs
!= NULL
)
5359 usr_store_inferior_registers (regs_info
, regcache
, regno
, all
);
5363 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
5365 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
5367 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
5368 usr_store_inferior_registers (regs_info
, regcache
, regno
, 1);
5373 /* Copy LEN bytes from inferior's memory starting at MEMADDR
5374 to debugger memory starting at MYADDR. */
5377 linux_read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
, int len
)
5379 int pid
= lwpid_of (current_thread
);
5380 register PTRACE_XFER_TYPE
*buffer
;
5381 register CORE_ADDR addr
;
5388 /* Try using /proc. Don't bother for one word. */
5389 if (len
>= 3 * sizeof (long))
5393 /* We could keep this file open and cache it - possibly one per
5394 thread. That requires some juggling, but is even faster. */
5395 sprintf (filename
, "/proc/%d/mem", pid
);
5396 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
5400 /* If pread64 is available, use it. It's faster if the kernel
5401 supports it (only one syscall), and it's 64-bit safe even on
5402 32-bit platforms (for instance, SPARC debugging a SPARC64
5405 bytes
= pread64 (fd
, myaddr
, len
, memaddr
);
5408 if (lseek (fd
, memaddr
, SEEK_SET
) != -1)
5409 bytes
= read (fd
, myaddr
, len
);
5416 /* Some data was read, we'll try to get the rest with ptrace. */
5426 /* Round starting address down to longword boundary. */
5427 addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
5428 /* Round ending address up; get number of longwords that makes. */
5429 count
= ((((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
5430 / sizeof (PTRACE_XFER_TYPE
));
5431 /* Allocate buffer of that many longwords. */
5432 buffer
= XALLOCAVEC (PTRACE_XFER_TYPE
, count
);
5434 /* Read all the longwords */
5436 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
5438 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5439 about coercing an 8 byte integer to a 4 byte pointer. */
5440 buffer
[i
] = ptrace (PTRACE_PEEKTEXT
, pid
,
5441 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5442 (PTRACE_TYPE_ARG4
) 0);
5448 /* Copy appropriate bytes out of the buffer. */
5451 i
*= sizeof (PTRACE_XFER_TYPE
);
5452 i
-= memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1);
5454 (char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
5461 /* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
5462 memory at MEMADDR. On failure (cannot write to the inferior)
5463 returns the value of errno. Always succeeds if LEN is zero. */
5466 linux_write_memory (CORE_ADDR memaddr
, const unsigned char *myaddr
, int len
)
5469 /* Round starting address down to longword boundary. */
5470 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
5471 /* Round ending address up; get number of longwords that makes. */
5473 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
5474 / sizeof (PTRACE_XFER_TYPE
);
5476 /* Allocate buffer of that many longwords. */
5477 register PTRACE_XFER_TYPE
*buffer
= XALLOCAVEC (PTRACE_XFER_TYPE
, count
);
5479 int pid
= lwpid_of (current_thread
);
5483 /* Zero length write always succeeds. */
5489 /* Dump up to four bytes. */
5490 char str
[4 * 2 + 1];
5492 int dump
= len
< 4 ? len
: 4;
5494 for (i
= 0; i
< dump
; i
++)
5496 sprintf (p
, "%02x", myaddr
[i
]);
5501 debug_printf ("Writing %s to 0x%08lx in process %d\n",
5502 str
, (long) memaddr
, pid
);
5505 /* Fill start and end extra bytes of buffer with existing memory data. */
5508 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5509 about coercing an 8 byte integer to a 4 byte pointer. */
5510 buffer
[0] = ptrace (PTRACE_PEEKTEXT
, pid
,
5511 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5512 (PTRACE_TYPE_ARG4
) 0);
5520 = ptrace (PTRACE_PEEKTEXT
, pid
,
5521 /* Coerce to a uintptr_t first to avoid potential gcc warning
5522 about coercing an 8 byte integer to a 4 byte pointer. */
5523 (PTRACE_TYPE_ARG3
) (uintptr_t) (addr
+ (count
- 1)
5524 * sizeof (PTRACE_XFER_TYPE
)),
5525 (PTRACE_TYPE_ARG4
) 0);
5530 /* Copy data to be written over corresponding part of buffer. */
5532 memcpy ((char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
5535 /* Write the entire buffer. */
5537 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
5540 ptrace (PTRACE_POKETEXT
, pid
,
5541 /* Coerce to a uintptr_t first to avoid potential gcc warning
5542 about coercing an 8 byte integer to a 4 byte pointer. */
5543 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5544 (PTRACE_TYPE_ARG4
) buffer
[i
]);
5553 linux_look_up_symbols (void)
5555 #ifdef USE_THREAD_DB
5556 struct process_info
*proc
= current_process ();
5558 if (proc
->priv
->thread_db
!= NULL
)
5561 /* If the kernel supports tracing clones, then we don't need to
5562 use the magic thread event breakpoint to learn about
5564 thread_db_init (!linux_supports_traceclone ());
5569 linux_request_interrupt (void)
5571 extern unsigned long signal_pid
;
5573 /* Send a SIGINT to the process group. This acts just like the user
5574 typed a ^C on the controlling terminal. */
5575 kill (-signal_pid
, SIGINT
);
5578 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
5579 to debugger memory starting at MYADDR. */
5582 linux_read_auxv (CORE_ADDR offset
, unsigned char *myaddr
, unsigned int len
)
5584 char filename
[PATH_MAX
];
5586 int pid
= lwpid_of (current_thread
);
5588 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
5590 fd
= open (filename
, O_RDONLY
);
5594 if (offset
!= (CORE_ADDR
) 0
5595 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
5598 n
= read (fd
, myaddr
, len
);
5605 /* These breakpoint and watchpoint related wrapper functions simply
5606 pass on the function call if the target has registered a
5607 corresponding function. */
5610 linux_supports_z_point_type (char z_type
)
5612 return (the_low_target
.supports_z_point_type
!= NULL
5613 && the_low_target
.supports_z_point_type (z_type
));
5617 linux_insert_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
5618 int size
, struct raw_breakpoint
*bp
)
5620 if (type
== raw_bkpt_type_sw
)
5621 return insert_memory_breakpoint (bp
);
5622 else if (the_low_target
.insert_point
!= NULL
)
5623 return the_low_target
.insert_point (type
, addr
, size
, bp
);
5625 /* Unsupported (see target.h). */
5630 linux_remove_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
5631 int size
, struct raw_breakpoint
*bp
)
5633 if (type
== raw_bkpt_type_sw
)
5634 return remove_memory_breakpoint (bp
);
5635 else if (the_low_target
.remove_point
!= NULL
)
5636 return the_low_target
.remove_point (type
, addr
, size
, bp
);
5638 /* Unsupported (see target.h). */
5642 /* Implement the to_stopped_by_sw_breakpoint target_ops
5646 linux_stopped_by_sw_breakpoint (void)
5648 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5650 return (lwp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
);
5653 /* Implement the to_supports_stopped_by_sw_breakpoint target_ops
5657 linux_supports_stopped_by_sw_breakpoint (void)
5659 return USE_SIGTRAP_SIGINFO
;
5662 /* Implement the to_stopped_by_hw_breakpoint target_ops
5666 linux_stopped_by_hw_breakpoint (void)
5668 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5670 return (lwp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
);
5673 /* Implement the to_supports_stopped_by_hw_breakpoint target_ops
5677 linux_supports_stopped_by_hw_breakpoint (void)
5679 return USE_SIGTRAP_SIGINFO
;
5682 /* Implement the supports_hardware_single_step target_ops method. */
5685 linux_supports_hardware_single_step (void)
5687 return can_hardware_single_step ();
5691 linux_stopped_by_watchpoint (void)
5693 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5695 return lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
;
5699 linux_stopped_data_address (void)
5701 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5703 return lwp
->stopped_data_address
;
5706 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
5707 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
5708 && defined(PT_TEXT_END_ADDR)
5710 /* This is only used for targets that define PT_TEXT_ADDR,
5711 PT_DATA_ADDR and PT_TEXT_END_ADDR. If those are not defined, supposedly
5712 the target has different ways of acquiring this information, like
5715 /* Under uClinux, programs are loaded at non-zero offsets, which we need
5716 to tell gdb about. */
5719 linux_read_offsets (CORE_ADDR
*text_p
, CORE_ADDR
*data_p
)
5721 unsigned long text
, text_end
, data
;
5722 int pid
= lwpid_of (current_thread
);
5726 text
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_ADDR
,
5727 (PTRACE_TYPE_ARG4
) 0);
5728 text_end
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_END_ADDR
,
5729 (PTRACE_TYPE_ARG4
) 0);
5730 data
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_DATA_ADDR
,
5731 (PTRACE_TYPE_ARG4
) 0);
5735 /* Both text and data offsets produced at compile-time (and so
5736 used by gdb) are relative to the beginning of the program,
5737 with the data segment immediately following the text segment.
5738 However, the actual runtime layout in memory may put the data
5739 somewhere else, so when we send gdb a data base-address, we
5740 use the real data base address and subtract the compile-time
5741 data base-address from it (which is just the length of the
5742 text segment). BSS immediately follows data in both
5745 *data_p
= data
- (text_end
- text
);
5754 linux_qxfer_osdata (const char *annex
,
5755 unsigned char *readbuf
, unsigned const char *writebuf
,
5756 CORE_ADDR offset
, int len
)
5758 return linux_common_xfer_osdata (annex
, readbuf
, offset
, len
);
5761 /* Convert a native/host siginfo object, into/from the siginfo in the
5762 layout of the inferiors' architecture. */
5765 siginfo_fixup (siginfo_t
*siginfo
, void *inf_siginfo
, int direction
)
5769 if (the_low_target
.siginfo_fixup
!= NULL
)
5770 done
= the_low_target
.siginfo_fixup (siginfo
, inf_siginfo
, direction
);
5772 /* If there was no callback, or the callback didn't do anything,
5773 then just do a straight memcpy. */
5777 memcpy (siginfo
, inf_siginfo
, sizeof (siginfo_t
));
5779 memcpy (inf_siginfo
, siginfo
, sizeof (siginfo_t
));
5784 linux_xfer_siginfo (const char *annex
, unsigned char *readbuf
,
5785 unsigned const char *writebuf
, CORE_ADDR offset
, int len
)
5789 char inf_siginfo
[sizeof (siginfo_t
)];
5791 if (current_thread
== NULL
)
5794 pid
= lwpid_of (current_thread
);
5797 debug_printf ("%s siginfo for lwp %d.\n",
5798 readbuf
!= NULL
? "Reading" : "Writing",
5801 if (offset
>= sizeof (siginfo
))
5804 if (ptrace (PTRACE_GETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
5807 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
5808 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
5809 inferior with a 64-bit GDBSERVER should look the same as debugging it
5810 with a 32-bit GDBSERVER, we need to convert it. */
5811 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
5813 if (offset
+ len
> sizeof (siginfo
))
5814 len
= sizeof (siginfo
) - offset
;
5816 if (readbuf
!= NULL
)
5817 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
5820 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
5822 /* Convert back to ptrace layout before flushing it out. */
5823 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
5825 if (ptrace (PTRACE_SETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
5832 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
5833 so we notice when children change state; as the handler for the
5834 sigsuspend in my_waitpid. */
5837 sigchld_handler (int signo
)
5839 int old_errno
= errno
;
5845 /* fprintf is not async-signal-safe, so call write
5847 if (write (2, "sigchld_handler\n",
5848 sizeof ("sigchld_handler\n") - 1) < 0)
5849 break; /* just ignore */
5853 if (target_is_async_p ())
5854 async_file_mark (); /* trigger a linux_wait */
5860 linux_supports_non_stop (void)
5866 linux_async (int enable
)
5868 int previous
= target_is_async_p ();
5871 debug_printf ("linux_async (%d), previous=%d\n",
5874 if (previous
!= enable
)
5877 sigemptyset (&mask
);
5878 sigaddset (&mask
, SIGCHLD
);
5880 sigprocmask (SIG_BLOCK
, &mask
, NULL
);
5884 if (pipe (linux_event_pipe
) == -1)
5886 linux_event_pipe
[0] = -1;
5887 linux_event_pipe
[1] = -1;
5888 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
5890 warning ("creating event pipe failed.");
5894 fcntl (linux_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
5895 fcntl (linux_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
5897 /* Register the event loop handler. */
5898 add_file_handler (linux_event_pipe
[0],
5899 handle_target_event
, NULL
);
5901 /* Always trigger a linux_wait. */
5906 delete_file_handler (linux_event_pipe
[0]);
5908 close (linux_event_pipe
[0]);
5909 close (linux_event_pipe
[1]);
5910 linux_event_pipe
[0] = -1;
5911 linux_event_pipe
[1] = -1;
5914 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
5921 linux_start_non_stop (int nonstop
)
5923 /* Register or unregister from event-loop accordingly. */
5924 linux_async (nonstop
);
5926 if (target_is_async_p () != (nonstop
!= 0))
5933 linux_supports_multi_process (void)
5938 /* Check if fork events are supported. */
5941 linux_supports_fork_events (void)
5943 return linux_supports_tracefork ();
5946 /* Check if vfork events are supported. */
5949 linux_supports_vfork_events (void)
5951 return linux_supports_tracefork ();
5954 /* Check if exec events are supported. */
5957 linux_supports_exec_events (void)
5959 return linux_supports_traceexec ();
5962 /* Callback for 'find_inferior'. Set the (possibly changed) ptrace
5963 options for the specified lwp. */
5966 reset_lwp_ptrace_options_callback (struct inferior_list_entry
*entry
,
5969 struct thread_info
*thread
= (struct thread_info
*) entry
;
5970 struct lwp_info
*lwp
= get_thread_lwp (thread
);
5974 /* Stop the lwp so we can modify its ptrace options. */
5975 lwp
->must_set_ptrace_flags
= 1;
5976 linux_stop_lwp (lwp
);
5980 /* Already stopped; go ahead and set the ptrace options. */
5981 struct process_info
*proc
= find_process_pid (pid_of (thread
));
5982 int options
= linux_low_ptrace_options (proc
->attached
);
5984 linux_enable_event_reporting (lwpid_of (thread
), options
);
5985 lwp
->must_set_ptrace_flags
= 0;
5991 /* Target hook for 'handle_new_gdb_connection'. Causes a reset of the
5992 ptrace flags for all inferiors. This is in case the new GDB connection
5993 doesn't support the same set of events that the previous one did. */
5996 linux_handle_new_gdb_connection (void)
6000 /* Request that all the lwps reset their ptrace options. */
6001 find_inferior (&all_threads
, reset_lwp_ptrace_options_callback
, &pid
);
6005 linux_supports_disable_randomization (void)
6007 #ifdef HAVE_PERSONALITY
6015 linux_supports_agent (void)
6021 linux_supports_range_stepping (void)
6023 if (*the_low_target
.supports_range_stepping
== NULL
)
6026 return (*the_low_target
.supports_range_stepping
) ();
6029 /* Enumerate spufs IDs for process PID. */
6031 spu_enumerate_spu_ids (long pid
, unsigned char *buf
, CORE_ADDR offset
, int len
)
6037 struct dirent
*entry
;
6039 sprintf (path
, "/proc/%ld/fd", pid
);
6040 dir
= opendir (path
);
6045 while ((entry
= readdir (dir
)) != NULL
)
6051 fd
= atoi (entry
->d_name
);
6055 sprintf (path
, "/proc/%ld/fd/%d", pid
, fd
);
6056 if (stat (path
, &st
) != 0)
6058 if (!S_ISDIR (st
.st_mode
))
6061 if (statfs (path
, &stfs
) != 0)
6063 if (stfs
.f_type
!= SPUFS_MAGIC
)
6066 if (pos
>= offset
&& pos
+ 4 <= offset
+ len
)
6068 *(unsigned int *)(buf
+ pos
- offset
) = fd
;
6078 /* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
6079 object type, using the /proc file system. */
6081 linux_qxfer_spu (const char *annex
, unsigned char *readbuf
,
6082 unsigned const char *writebuf
,
6083 CORE_ADDR offset
, int len
)
6085 long pid
= lwpid_of (current_thread
);
6090 if (!writebuf
&& !readbuf
)
6098 return spu_enumerate_spu_ids (pid
, readbuf
, offset
, len
);
6101 sprintf (buf
, "/proc/%ld/fd/%s", pid
, annex
);
6102 fd
= open (buf
, writebuf
? O_WRONLY
: O_RDONLY
);
6107 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
6114 ret
= write (fd
, writebuf
, (size_t) len
);
6116 ret
= read (fd
, readbuf
, (size_t) len
);
6122 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
6123 struct target_loadseg
6125 /* Core address to which the segment is mapped. */
6127 /* VMA recorded in the program header. */
6129 /* Size of this segment in memory. */
6133 # if defined PT_GETDSBT
6134 struct target_loadmap
6136 /* Protocol version number, must be zero. */
6138 /* Pointer to the DSBT table, its size, and the DSBT index. */
6139 unsigned *dsbt_table
;
6140 unsigned dsbt_size
, dsbt_index
;
6141 /* Number of segments in this map. */
6143 /* The actual memory map. */
6144 struct target_loadseg segs
[/*nsegs*/];
6146 # define LINUX_LOADMAP PT_GETDSBT
6147 # define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
6148 # define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
6150 struct target_loadmap
6152 /* Protocol version number, must be zero. */
6154 /* Number of segments in this map. */
6156 /* The actual memory map. */
6157 struct target_loadseg segs
[/*nsegs*/];
6159 # define LINUX_LOADMAP PTRACE_GETFDPIC
6160 # define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
6161 # define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
6165 linux_read_loadmap (const char *annex
, CORE_ADDR offset
,
6166 unsigned char *myaddr
, unsigned int len
)
6168 int pid
= lwpid_of (current_thread
);
6170 struct target_loadmap
*data
= NULL
;
6171 unsigned int actual_length
, copy_length
;
6173 if (strcmp (annex
, "exec") == 0)
6174 addr
= (int) LINUX_LOADMAP_EXEC
;
6175 else if (strcmp (annex
, "interp") == 0)
6176 addr
= (int) LINUX_LOADMAP_INTERP
;
6180 if (ptrace (LINUX_LOADMAP
, pid
, addr
, &data
) != 0)
6186 actual_length
= sizeof (struct target_loadmap
)
6187 + sizeof (struct target_loadseg
) * data
->nsegs
;
6189 if (offset
< 0 || offset
> actual_length
)
6192 copy_length
= actual_length
- offset
< len
? actual_length
- offset
: len
;
6193 memcpy (myaddr
, (char *) data
+ offset
, copy_length
);
6197 # define linux_read_loadmap NULL
6198 #endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
6201 linux_process_qsupported (char **features
, int count
)
6203 if (the_low_target
.process_qsupported
!= NULL
)
6204 the_low_target
.process_qsupported (features
, count
);
6208 linux_supports_tracepoints (void)
6210 if (*the_low_target
.supports_tracepoints
== NULL
)
6213 return (*the_low_target
.supports_tracepoints
) ();
6217 linux_read_pc (struct regcache
*regcache
)
6219 if (the_low_target
.get_pc
== NULL
)
6222 return (*the_low_target
.get_pc
) (regcache
);
6226 linux_write_pc (struct regcache
*regcache
, CORE_ADDR pc
)
6228 gdb_assert (the_low_target
.set_pc
!= NULL
);
6230 (*the_low_target
.set_pc
) (regcache
, pc
);
6234 linux_thread_stopped (struct thread_info
*thread
)
6236 return get_thread_lwp (thread
)->stopped
;
6239 /* This exposes stop-all-threads functionality to other modules. */
6242 linux_pause_all (int freeze
)
6244 stop_all_lwps (freeze
, NULL
);
6247 /* This exposes unstop-all-threads functionality to other gdbserver
6251 linux_unpause_all (int unfreeze
)
6253 unstop_all_lwps (unfreeze
, NULL
);
6257 linux_prepare_to_access_memory (void)
6259 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6262 linux_pause_all (1);
6267 linux_done_accessing_memory (void)
6269 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6272 linux_unpause_all (1);
6276 linux_install_fast_tracepoint_jump_pad (CORE_ADDR tpoint
, CORE_ADDR tpaddr
,
6277 CORE_ADDR collector
,
6280 CORE_ADDR
*jump_entry
,
6281 CORE_ADDR
*trampoline
,
6282 ULONGEST
*trampoline_size
,
6283 unsigned char *jjump_pad_insn
,
6284 ULONGEST
*jjump_pad_insn_size
,
6285 CORE_ADDR
*adjusted_insn_addr
,
6286 CORE_ADDR
*adjusted_insn_addr_end
,
6289 return (*the_low_target
.install_fast_tracepoint_jump_pad
)
6290 (tpoint
, tpaddr
, collector
, lockaddr
, orig_size
,
6291 jump_entry
, trampoline
, trampoline_size
,
6292 jjump_pad_insn
, jjump_pad_insn_size
,
6293 adjusted_insn_addr
, adjusted_insn_addr_end
,
6297 static struct emit_ops
*
6298 linux_emit_ops (void)
6300 if (the_low_target
.emit_ops
!= NULL
)
6301 return (*the_low_target
.emit_ops
) ();
6307 linux_get_min_fast_tracepoint_insn_len (void)
6309 return (*the_low_target
.get_min_fast_tracepoint_insn_len
) ();
6312 /* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
6315 get_phdr_phnum_from_proc_auxv (const int pid
, const int is_elf64
,
6316 CORE_ADDR
*phdr_memaddr
, int *num_phdr
)
6318 char filename
[PATH_MAX
];
6320 const int auxv_size
= is_elf64
6321 ? sizeof (Elf64_auxv_t
) : sizeof (Elf32_auxv_t
);
6322 char buf
[sizeof (Elf64_auxv_t
)]; /* The larger of the two. */
6324 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
6326 fd
= open (filename
, O_RDONLY
);
6332 while (read (fd
, buf
, auxv_size
) == auxv_size
6333 && (*phdr_memaddr
== 0 || *num_phdr
== 0))
6337 Elf64_auxv_t
*const aux
= (Elf64_auxv_t
*) buf
;
6339 switch (aux
->a_type
)
6342 *phdr_memaddr
= aux
->a_un
.a_val
;
6345 *num_phdr
= aux
->a_un
.a_val
;
6351 Elf32_auxv_t
*const aux
= (Elf32_auxv_t
*) buf
;
6353 switch (aux
->a_type
)
6356 *phdr_memaddr
= aux
->a_un
.a_val
;
6359 *num_phdr
= aux
->a_un
.a_val
;
6367 if (*phdr_memaddr
== 0 || *num_phdr
== 0)
6369 warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
6370 "phdr_memaddr = %ld, phdr_num = %d",
6371 (long) *phdr_memaddr
, *num_phdr
);
6378 /* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
6381 get_dynamic (const int pid
, const int is_elf64
)
6383 CORE_ADDR phdr_memaddr
, relocation
;
6385 unsigned char *phdr_buf
;
6386 const int phdr_size
= is_elf64
? sizeof (Elf64_Phdr
) : sizeof (Elf32_Phdr
);
6388 if (get_phdr_phnum_from_proc_auxv (pid
, is_elf64
, &phdr_memaddr
, &num_phdr
))
6391 gdb_assert (num_phdr
< 100); /* Basic sanity check. */
6392 phdr_buf
= (unsigned char *) alloca (num_phdr
* phdr_size
);
6394 if (linux_read_memory (phdr_memaddr
, phdr_buf
, num_phdr
* phdr_size
))
6397 /* Compute relocation: it is expected to be 0 for "regular" executables,
6398 non-zero for PIE ones. */
6400 for (i
= 0; relocation
== -1 && i
< num_phdr
; i
++)
6403 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6405 if (p
->p_type
== PT_PHDR
)
6406 relocation
= phdr_memaddr
- p
->p_vaddr
;
6410 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6412 if (p
->p_type
== PT_PHDR
)
6413 relocation
= phdr_memaddr
- p
->p_vaddr
;
6416 if (relocation
== -1)
6418 /* PT_PHDR is optional, but necessary for PIE in general. Fortunately
6419 any real world executables, including PIE executables, have always
6420 PT_PHDR present. PT_PHDR is not present in some shared libraries or
6421 in fpc (Free Pascal 2.4) binaries but neither of those have a need for
6422 or present DT_DEBUG anyway (fpc binaries are statically linked).
6424 Therefore if there exists DT_DEBUG there is always also PT_PHDR.
6426 GDB could find RELOCATION also from AT_ENTRY - e_entry. */
6431 for (i
= 0; i
< num_phdr
; i
++)
6435 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6437 if (p
->p_type
== PT_DYNAMIC
)
6438 return p
->p_vaddr
+ relocation
;
6442 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6444 if (p
->p_type
== PT_DYNAMIC
)
6445 return p
->p_vaddr
+ relocation
;
6452 /* Return &_r_debug in the inferior, or -1 if not present. Return value
6453 can be 0 if the inferior does not yet have the library list initialized.
6454 We look for DT_MIPS_RLD_MAP first. MIPS executables use this instead of
6455 DT_DEBUG, although they sometimes contain an unused DT_DEBUG entry too. */
6458 get_r_debug (const int pid
, const int is_elf64
)
6460 CORE_ADDR dynamic_memaddr
;
6461 const int dyn_size
= is_elf64
? sizeof (Elf64_Dyn
) : sizeof (Elf32_Dyn
);
6462 unsigned char buf
[sizeof (Elf64_Dyn
)]; /* The larger of the two. */
6465 dynamic_memaddr
= get_dynamic (pid
, is_elf64
);
6466 if (dynamic_memaddr
== 0)
6469 while (linux_read_memory (dynamic_memaddr
, buf
, dyn_size
) == 0)
6473 Elf64_Dyn
*const dyn
= (Elf64_Dyn
*) buf
;
6474 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
6478 unsigned char buf
[sizeof (Elf64_Xword
)];
6482 #ifdef DT_MIPS_RLD_MAP
6483 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
6485 if (linux_read_memory (dyn
->d_un
.d_val
,
6486 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6491 #endif /* DT_MIPS_RLD_MAP */
6492 #ifdef DT_MIPS_RLD_MAP_REL
6493 if (dyn
->d_tag
== DT_MIPS_RLD_MAP_REL
)
6495 if (linux_read_memory (dyn
->d_un
.d_val
+ dynamic_memaddr
,
6496 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6501 #endif /* DT_MIPS_RLD_MAP_REL */
6503 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
6504 map
= dyn
->d_un
.d_val
;
6506 if (dyn
->d_tag
== DT_NULL
)
6511 Elf32_Dyn
*const dyn
= (Elf32_Dyn
*) buf
;
6512 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
6516 unsigned char buf
[sizeof (Elf32_Word
)];
6520 #ifdef DT_MIPS_RLD_MAP
6521 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
6523 if (linux_read_memory (dyn
->d_un
.d_val
,
6524 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6529 #endif /* DT_MIPS_RLD_MAP */
6530 #ifdef DT_MIPS_RLD_MAP_REL
6531 if (dyn
->d_tag
== DT_MIPS_RLD_MAP_REL
)
6533 if (linux_read_memory (dyn
->d_un
.d_val
+ dynamic_memaddr
,
6534 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6539 #endif /* DT_MIPS_RLD_MAP_REL */
6541 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
6542 map
= dyn
->d_un
.d_val
;
6544 if (dyn
->d_tag
== DT_NULL
)
6548 dynamic_memaddr
+= dyn_size
;
6554 /* Read one pointer from MEMADDR in the inferior. */
6557 read_one_ptr (CORE_ADDR memaddr
, CORE_ADDR
*ptr
, int ptr_size
)
6561 /* Go through a union so this works on either big or little endian
6562 hosts, when the inferior's pointer size is smaller than the size
6563 of CORE_ADDR. It is assumed the inferior's endianness is the
6564 same of the superior's. */
6567 CORE_ADDR core_addr
;
6572 ret
= linux_read_memory (memaddr
, &addr
.uc
, ptr_size
);
6575 if (ptr_size
== sizeof (CORE_ADDR
))
6576 *ptr
= addr
.core_addr
;
6577 else if (ptr_size
== sizeof (unsigned int))
6580 gdb_assert_not_reached ("unhandled pointer size");
6585 struct link_map_offsets
6587 /* Offset and size of r_debug.r_version. */
6588 int r_version_offset
;
6590 /* Offset and size of r_debug.r_map. */
6593 /* Offset to l_addr field in struct link_map. */
6596 /* Offset to l_name field in struct link_map. */
6599 /* Offset to l_ld field in struct link_map. */
6602 /* Offset to l_next field in struct link_map. */
6605 /* Offset to l_prev field in struct link_map. */
6609 /* Construct qXfer:libraries-svr4:read reply. */
6612 linux_qxfer_libraries_svr4 (const char *annex
, unsigned char *readbuf
,
6613 unsigned const char *writebuf
,
6614 CORE_ADDR offset
, int len
)
6617 unsigned document_len
;
6618 struct process_info_private
*const priv
= current_process ()->priv
;
6619 char filename
[PATH_MAX
];
6622 static const struct link_map_offsets lmo_32bit_offsets
=
6624 0, /* r_version offset. */
6625 4, /* r_debug.r_map offset. */
6626 0, /* l_addr offset in link_map. */
6627 4, /* l_name offset in link_map. */
6628 8, /* l_ld offset in link_map. */
6629 12, /* l_next offset in link_map. */
6630 16 /* l_prev offset in link_map. */
6633 static const struct link_map_offsets lmo_64bit_offsets
=
6635 0, /* r_version offset. */
6636 8, /* r_debug.r_map offset. */
6637 0, /* l_addr offset in link_map. */
6638 8, /* l_name offset in link_map. */
6639 16, /* l_ld offset in link_map. */
6640 24, /* l_next offset in link_map. */
6641 32 /* l_prev offset in link_map. */
6643 const struct link_map_offsets
*lmo
;
6644 unsigned int machine
;
6646 CORE_ADDR lm_addr
= 0, lm_prev
= 0;
6647 int allocated
= 1024;
6649 CORE_ADDR l_name
, l_addr
, l_ld
, l_next
, l_prev
;
6650 int header_done
= 0;
6652 if (writebuf
!= NULL
)
6654 if (readbuf
== NULL
)
6657 pid
= lwpid_of (current_thread
);
6658 xsnprintf (filename
, sizeof filename
, "/proc/%d/exe", pid
);
6659 is_elf64
= elf_64_file_p (filename
, &machine
);
6660 lmo
= is_elf64
? &lmo_64bit_offsets
: &lmo_32bit_offsets
;
6661 ptr_size
= is_elf64
? 8 : 4;
6663 while (annex
[0] != '\0')
6669 sep
= strchr (annex
, '=');
6674 if (len
== 5 && startswith (annex
, "start"))
6676 else if (len
== 4 && startswith (annex
, "prev"))
6680 annex
= strchr (sep
, ';');
6687 annex
= decode_address_to_semicolon (addrp
, sep
+ 1);
6694 if (priv
->r_debug
== 0)
6695 priv
->r_debug
= get_r_debug (pid
, is_elf64
);
6697 /* We failed to find DT_DEBUG. Such situation will not change
6698 for this inferior - do not retry it. Report it to GDB as
6699 E01, see for the reasons at the GDB solib-svr4.c side. */
6700 if (priv
->r_debug
== (CORE_ADDR
) -1)
6703 if (priv
->r_debug
!= 0)
6705 if (linux_read_memory (priv
->r_debug
+ lmo
->r_version_offset
,
6706 (unsigned char *) &r_version
,
6707 sizeof (r_version
)) != 0
6710 warning ("unexpected r_debug version %d", r_version
);
6712 else if (read_one_ptr (priv
->r_debug
+ lmo
->r_map_offset
,
6713 &lm_addr
, ptr_size
) != 0)
6715 warning ("unable to read r_map from 0x%lx",
6716 (long) priv
->r_debug
+ lmo
->r_map_offset
);
6721 document
= (char *) xmalloc (allocated
);
6722 strcpy (document
, "<library-list-svr4 version=\"1.0\"");
6723 p
= document
+ strlen (document
);
6726 && read_one_ptr (lm_addr
+ lmo
->l_name_offset
,
6727 &l_name
, ptr_size
) == 0
6728 && read_one_ptr (lm_addr
+ lmo
->l_addr_offset
,
6729 &l_addr
, ptr_size
) == 0
6730 && read_one_ptr (lm_addr
+ lmo
->l_ld_offset
,
6731 &l_ld
, ptr_size
) == 0
6732 && read_one_ptr (lm_addr
+ lmo
->l_prev_offset
,
6733 &l_prev
, ptr_size
) == 0
6734 && read_one_ptr (lm_addr
+ lmo
->l_next_offset
,
6735 &l_next
, ptr_size
) == 0)
6737 unsigned char libname
[PATH_MAX
];
6739 if (lm_prev
!= l_prev
)
6741 warning ("Corrupted shared library list: 0x%lx != 0x%lx",
6742 (long) lm_prev
, (long) l_prev
);
6746 /* Ignore the first entry even if it has valid name as the first entry
6747 corresponds to the main executable. The first entry should not be
6748 skipped if the dynamic loader was loaded late by a static executable
6749 (see solib-svr4.c parameter ignore_first). But in such case the main
6750 executable does not have PT_DYNAMIC present and this function already
6751 exited above due to failed get_r_debug. */
6754 sprintf (p
, " main-lm=\"0x%lx\"", (unsigned long) lm_addr
);
6759 /* Not checking for error because reading may stop before
6760 we've got PATH_MAX worth of characters. */
6762 linux_read_memory (l_name
, libname
, sizeof (libname
) - 1);
6763 libname
[sizeof (libname
) - 1] = '\0';
6764 if (libname
[0] != '\0')
6766 /* 6x the size for xml_escape_text below. */
6767 size_t len
= 6 * strlen ((char *) libname
);
6772 /* Terminate `<library-list-svr4'. */
6777 while (allocated
< p
- document
+ len
+ 200)
6779 /* Expand to guarantee sufficient storage. */
6780 uintptr_t document_len
= p
- document
;
6782 document
= (char *) xrealloc (document
, 2 * allocated
);
6784 p
= document
+ document_len
;
6787 name
= xml_escape_text ((char *) libname
);
6788 p
+= sprintf (p
, "<library name=\"%s\" lm=\"0x%lx\" "
6789 "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
6790 name
, (unsigned long) lm_addr
,
6791 (unsigned long) l_addr
, (unsigned long) l_ld
);
6802 /* Empty list; terminate `<library-list-svr4'. */
6806 strcpy (p
, "</library-list-svr4>");
6808 document_len
= strlen (document
);
6809 if (offset
< document_len
)
6810 document_len
-= offset
;
6813 if (len
> document_len
)
6816 memcpy (readbuf
, document
+ offset
, len
);
6822 #ifdef HAVE_LINUX_BTRACE
6824 /* See to_disable_btrace target method. */
6827 linux_low_disable_btrace (struct btrace_target_info
*tinfo
)
6829 enum btrace_error err
;
6831 err
= linux_disable_btrace (tinfo
);
6832 return (err
== BTRACE_ERR_NONE
? 0 : -1);
6835 /* Encode an Intel(R) Processor Trace configuration. */
6838 linux_low_encode_pt_config (struct buffer
*buffer
,
6839 const struct btrace_data_pt_config
*config
)
6841 buffer_grow_str (buffer
, "<pt-config>\n");
6843 switch (config
->cpu
.vendor
)
6846 buffer_xml_printf (buffer
, "<cpu vendor=\"GenuineIntel\" family=\"%u\" "
6847 "model=\"%u\" stepping=\"%u\"/>\n",
6848 config
->cpu
.family
, config
->cpu
.model
,
6849 config
->cpu
.stepping
);
6856 buffer_grow_str (buffer
, "</pt-config>\n");
6859 /* Encode a raw buffer. */
6862 linux_low_encode_raw (struct buffer
*buffer
, const gdb_byte
*data
,
6868 /* We use hex encoding - see common/rsp-low.h. */
6869 buffer_grow_str (buffer
, "<raw>\n");
6875 elem
[0] = tohex ((*data
>> 4) & 0xf);
6876 elem
[1] = tohex (*data
++ & 0xf);
6878 buffer_grow (buffer
, elem
, 2);
6881 buffer_grow_str (buffer
, "</raw>\n");
6884 /* See to_read_btrace target method. */
6887 linux_low_read_btrace (struct btrace_target_info
*tinfo
, struct buffer
*buffer
,
6888 enum btrace_read_type type
)
6890 struct btrace_data btrace
;
6891 struct btrace_block
*block
;
6892 enum btrace_error err
;
6895 btrace_data_init (&btrace
);
6897 err
= linux_read_btrace (&btrace
, tinfo
, type
);
6898 if (err
!= BTRACE_ERR_NONE
)
6900 if (err
== BTRACE_ERR_OVERFLOW
)
6901 buffer_grow_str0 (buffer
, "E.Overflow.");
6903 buffer_grow_str0 (buffer
, "E.Generic Error.");
6908 switch (btrace
.format
)
6910 case BTRACE_FORMAT_NONE
:
6911 buffer_grow_str0 (buffer
, "E.No Trace.");
6914 case BTRACE_FORMAT_BTS
:
6915 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
6916 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
6919 VEC_iterate (btrace_block_s
, btrace
.variant
.bts
.blocks
, i
, block
);
6921 buffer_xml_printf (buffer
, "<block begin=\"0x%s\" end=\"0x%s\"/>\n",
6922 paddress (block
->begin
), paddress (block
->end
));
6924 buffer_grow_str0 (buffer
, "</btrace>\n");
6927 case BTRACE_FORMAT_PT
:
6928 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
6929 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
6930 buffer_grow_str (buffer
, "<pt>\n");
6932 linux_low_encode_pt_config (buffer
, &btrace
.variant
.pt
.config
);
6934 linux_low_encode_raw (buffer
, btrace
.variant
.pt
.data
,
6935 btrace
.variant
.pt
.size
);
6937 buffer_grow_str (buffer
, "</pt>\n");
6938 buffer_grow_str0 (buffer
, "</btrace>\n");
6942 buffer_grow_str0 (buffer
, "E.Unsupported Trace Format.");
6946 btrace_data_fini (&btrace
);
6950 btrace_data_fini (&btrace
);
6954 /* See to_btrace_conf target method. */
6957 linux_low_btrace_conf (const struct btrace_target_info
*tinfo
,
6958 struct buffer
*buffer
)
6960 const struct btrace_config
*conf
;
6962 buffer_grow_str (buffer
, "<!DOCTYPE btrace-conf SYSTEM \"btrace-conf.dtd\">\n");
6963 buffer_grow_str (buffer
, "<btrace-conf version=\"1.0\">\n");
6965 conf
= linux_btrace_conf (tinfo
);
6968 switch (conf
->format
)
6970 case BTRACE_FORMAT_NONE
:
6973 case BTRACE_FORMAT_BTS
:
6974 buffer_xml_printf (buffer
, "<bts");
6975 buffer_xml_printf (buffer
, " size=\"0x%x\"", conf
->bts
.size
);
6976 buffer_xml_printf (buffer
, " />\n");
6979 case BTRACE_FORMAT_PT
:
6980 buffer_xml_printf (buffer
, "<pt");
6981 buffer_xml_printf (buffer
, " size=\"0x%x\"", conf
->pt
.size
);
6982 buffer_xml_printf (buffer
, "/>\n");
6987 buffer_grow_str0 (buffer
, "</btrace-conf>\n");
6990 #endif /* HAVE_LINUX_BTRACE */
6992 /* See nat/linux-nat.h. */
6995 current_lwp_ptid (void)
6997 return ptid_of (current_thread
);
7000 /* Implementation of the target_ops method "breakpoint_kind_from_pc". */
7003 linux_breakpoint_kind_from_pc (CORE_ADDR
*pcptr
)
7005 if (the_low_target
.breakpoint_kind_from_pc
!= NULL
)
7006 return (*the_low_target
.breakpoint_kind_from_pc
) (pcptr
);
7008 return default_breakpoint_kind_from_pc (pcptr
);
7011 /* Implementation of the target_ops method "sw_breakpoint_from_kind". */
7013 static const gdb_byte
*
7014 linux_sw_breakpoint_from_kind (int kind
, int *size
)
7016 gdb_assert (the_low_target
.sw_breakpoint_from_kind
!= NULL
);
7018 return (*the_low_target
.sw_breakpoint_from_kind
) (kind
, size
);
7021 static struct target_ops linux_target_ops
= {
7022 linux_create_inferior
,
7032 linux_fetch_registers
,
7033 linux_store_registers
,
7034 linux_prepare_to_access_memory
,
7035 linux_done_accessing_memory
,
7038 linux_look_up_symbols
,
7039 linux_request_interrupt
,
7041 linux_supports_z_point_type
,
7044 linux_stopped_by_sw_breakpoint
,
7045 linux_supports_stopped_by_sw_breakpoint
,
7046 linux_stopped_by_hw_breakpoint
,
7047 linux_supports_stopped_by_hw_breakpoint
,
7048 linux_supports_hardware_single_step
,
7049 linux_stopped_by_watchpoint
,
7050 linux_stopped_data_address
,
7051 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
7052 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
7053 && defined(PT_TEXT_END_ADDR)
7058 #ifdef USE_THREAD_DB
7059 thread_db_get_tls_address
,
7064 hostio_last_error_from_errno
,
7067 linux_supports_non_stop
,
7069 linux_start_non_stop
,
7070 linux_supports_multi_process
,
7071 linux_supports_fork_events
,
7072 linux_supports_vfork_events
,
7073 linux_supports_exec_events
,
7074 linux_handle_new_gdb_connection
,
7075 #ifdef USE_THREAD_DB
7076 thread_db_handle_monitor_command
,
7080 linux_common_core_of_thread
,
7082 linux_process_qsupported
,
7083 linux_supports_tracepoints
,
7086 linux_thread_stopped
,
7090 linux_stabilize_threads
,
7091 linux_install_fast_tracepoint_jump_pad
,
7093 linux_supports_disable_randomization
,
7094 linux_get_min_fast_tracepoint_insn_len
,
7095 linux_qxfer_libraries_svr4
,
7096 linux_supports_agent
,
7097 #ifdef HAVE_LINUX_BTRACE
7098 linux_supports_btrace
,
7099 linux_enable_btrace
,
7100 linux_low_disable_btrace
,
7101 linux_low_read_btrace
,
7102 linux_low_btrace_conf
,
7110 linux_supports_range_stepping
,
7111 linux_proc_pid_to_exec_file
,
7112 linux_mntns_open_cloexec
,
7114 linux_mntns_readlink
,
7115 linux_breakpoint_kind_from_pc
,
7116 linux_sw_breakpoint_from_kind
,
7117 linux_proc_tid_get_name
,
7121 linux_init_signals ()
7123 /* FIXME drow/2002-06-09: As above, we should check with LinuxThreads
7124 to find what the cancel signal actually is. */
7125 #ifndef __ANDROID__ /* Bionic doesn't use SIGRTMIN the way glibc does. */
7126 signal (__SIGRTMIN
+1, SIG_IGN
);
7130 #ifdef HAVE_LINUX_REGSETS
7132 initialize_regsets_info (struct regsets_info
*info
)
7134 for (info
->num_regsets
= 0;
7135 info
->regsets
[info
->num_regsets
].size
>= 0;
7136 info
->num_regsets
++)
7142 initialize_low (void)
7144 struct sigaction sigchld_action
;
7146 memset (&sigchld_action
, 0, sizeof (sigchld_action
));
7147 set_target_ops (&linux_target_ops
);
7149 linux_init_signals ();
7150 linux_ptrace_init_warnings ();
7152 sigchld_action
.sa_handler
= sigchld_handler
;
7153 sigemptyset (&sigchld_action
.sa_mask
);
7154 sigchld_action
.sa_flags
= SA_RESTART
;
7155 sigaction (SIGCHLD
, &sigchld_action
, NULL
);
7157 initialize_low_arch ();
7159 linux_check_ptrace_features ();