1 /* Low level interface to ptrace, for the remote server for GDB.
2 Copyright (C) 1995-2022 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"
22 #include "gdbsupport/agent.h"
24 #include "gdbsupport/rsp-low.h"
25 #include "gdbsupport/signals-state-save-restore.h"
26 #include "nat/linux-nat.h"
27 #include "nat/linux-waitpid.h"
28 #include "gdbsupport/gdb_wait.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 "gdbsupport/filestuff.h"
47 #include "tracepoint.h"
49 #include "gdbsupport/common-inferior.h"
50 #include "nat/fork-inferior.h"
51 #include "gdbsupport/environ.h"
52 #include "gdbsupport/gdb-sigmask.h"
53 #include "gdbsupport/scoped_restore.h"
55 /* Don't include <linux/elf.h> here. If it got included by gdb_proc_service.h
56 then ELFMAG0 will have been defined. If it didn't get included by
57 gdb_proc_service.h then including it will likely introduce a duplicate
58 definition of elf_fpregset_t. */
61 #include "nat/linux-namespaces.h"
71 /* Some targets did not define these ptrace constants from the start,
72 so gdbserver defines them locally here. In the future, these may
73 be removed after they are added to asm/ptrace.h. */
74 #if !(defined(PT_TEXT_ADDR) \
75 || defined(PT_DATA_ADDR) \
76 || defined(PT_TEXT_END_ADDR))
77 #if defined(__mcoldfire__)
78 /* These are still undefined in 3.10 kernels. */
79 #define PT_TEXT_ADDR 49*4
80 #define PT_DATA_ADDR 50*4
81 #define PT_TEXT_END_ADDR 51*4
82 /* These are still undefined in 3.10 kernels. */
83 #elif defined(__TMS320C6X__)
84 #define PT_TEXT_ADDR (0x10000*4)
85 #define PT_DATA_ADDR (0x10004*4)
86 #define PT_TEXT_END_ADDR (0x10008*4)
90 #if (defined(__UCLIBC__) \
91 && defined(HAS_NOMMU) \
92 && defined(PT_TEXT_ADDR) \
93 && defined(PT_DATA_ADDR) \
94 && defined(PT_TEXT_END_ADDR))
95 #define SUPPORTS_READ_OFFSETS
98 #ifdef HAVE_LINUX_BTRACE
99 # include "nat/linux-btrace.h"
100 # include "gdbsupport/btrace-common.h"
103 #ifndef HAVE_ELF32_AUXV_T
104 /* Copied from glibc's elf.h. */
107 uint32_t a_type
; /* Entry type */
110 uint32_t a_val
; /* Integer value */
111 /* We use to have pointer elements added here. We cannot do that,
112 though, since it does not work when using 32-bit definitions
113 on 64-bit platforms and vice versa. */
118 #ifndef HAVE_ELF64_AUXV_T
119 /* Copied from glibc's elf.h. */
122 uint64_t a_type
; /* Entry type */
125 uint64_t a_val
; /* Integer value */
126 /* We use to have pointer elements added here. We cannot do that,
127 though, since it does not work when using 32-bit definitions
128 on 64-bit platforms and vice versa. */
133 /* Does the current host support PTRACE_GETREGSET? */
134 int have_ptrace_getregset
= -1;
138 /* See nat/linux-nat.h. */
141 ptid_of_lwp (struct lwp_info
*lwp
)
143 return ptid_of (get_lwp_thread (lwp
));
146 /* See nat/linux-nat.h. */
149 lwp_set_arch_private_info (struct lwp_info
*lwp
,
150 struct arch_lwp_info
*info
)
152 lwp
->arch_private
= info
;
155 /* See nat/linux-nat.h. */
157 struct arch_lwp_info
*
158 lwp_arch_private_info (struct lwp_info
*lwp
)
160 return lwp
->arch_private
;
163 /* See nat/linux-nat.h. */
166 lwp_is_stopped (struct lwp_info
*lwp
)
171 /* See nat/linux-nat.h. */
173 enum target_stop_reason
174 lwp_stop_reason (struct lwp_info
*lwp
)
176 return lwp
->stop_reason
;
179 /* See nat/linux-nat.h. */
182 lwp_is_stepping (struct lwp_info
*lwp
)
184 return lwp
->stepping
;
187 /* A list of all unknown processes which receive stop signals. Some
188 other process will presumably claim each of these as forked
189 children momentarily. */
191 struct simple_pid_list
193 /* The process ID. */
196 /* The status as reported by waitpid. */
200 struct simple_pid_list
*next
;
202 static struct simple_pid_list
*stopped_pids
;
204 /* Trivial list manipulation functions to keep track of a list of new
205 stopped processes. */
208 add_to_pid_list (struct simple_pid_list
**listp
, int pid
, int status
)
210 struct simple_pid_list
*new_pid
= XNEW (struct simple_pid_list
);
213 new_pid
->status
= status
;
214 new_pid
->next
= *listp
;
219 pull_pid_from_list (struct simple_pid_list
**listp
, int pid
, int *statusp
)
221 struct simple_pid_list
**p
;
223 for (p
= listp
; *p
!= NULL
; p
= &(*p
)->next
)
224 if ((*p
)->pid
== pid
)
226 struct simple_pid_list
*next
= (*p
)->next
;
228 *statusp
= (*p
)->status
;
236 enum stopping_threads_kind
238 /* Not stopping threads presently. */
239 NOT_STOPPING_THREADS
,
241 /* Stopping threads. */
244 /* Stopping and suspending threads. */
245 STOPPING_AND_SUSPENDING_THREADS
248 /* This is set while stop_all_lwps is in effect. */
249 static stopping_threads_kind stopping_threads
= NOT_STOPPING_THREADS
;
251 /* FIXME make into a target method? */
252 int using_threads
= 1;
254 /* True if we're presently stabilizing threads (moving them out of
256 static int stabilizing_threads
;
258 static void unsuspend_all_lwps (struct lwp_info
*except
);
259 static void mark_lwp_dead (struct lwp_info
*lwp
, int wstat
);
260 static int lwp_is_marked_dead (struct lwp_info
*lwp
);
261 static int kill_lwp (unsigned long lwpid
, int signo
);
262 static void enqueue_pending_signal (struct lwp_info
*lwp
, int signal
, siginfo_t
*info
);
263 static int linux_low_ptrace_options (int attached
);
264 static int check_ptrace_stopped_lwp_gone (struct lwp_info
*lp
);
266 /* When the event-loop is doing a step-over, this points at the thread
268 static ptid_t step_over_bkpt
;
271 linux_process_target::low_supports_breakpoints ()
277 linux_process_target::low_get_pc (regcache
*regcache
)
283 linux_process_target::low_set_pc (regcache
*regcache
, CORE_ADDR newpc
)
285 gdb_assert_not_reached ("linux target op low_set_pc is not implemented");
288 std::vector
<CORE_ADDR
>
289 linux_process_target::low_get_next_pcs (regcache
*regcache
)
291 gdb_assert_not_reached ("linux target op low_get_next_pcs is not "
296 linux_process_target::low_decr_pc_after_break ()
301 /* True if LWP is stopped in its stepping range. */
304 lwp_in_step_range (struct lwp_info
*lwp
)
306 CORE_ADDR pc
= lwp
->stop_pc
;
308 return (pc
>= lwp
->step_range_start
&& pc
< lwp
->step_range_end
);
311 /* The read/write ends of the pipe registered as waitable file in the
313 static int linux_event_pipe
[2] = { -1, -1 };
315 /* True if we're currently in async mode. */
316 #define target_is_async_p() (linux_event_pipe[0] != -1)
318 static void send_sigstop (struct lwp_info
*lwp
);
320 /* Return non-zero if HEADER is a 64-bit ELF file. */
323 elf_64_header_p (const Elf64_Ehdr
*header
, unsigned int *machine
)
325 if (header
->e_ident
[EI_MAG0
] == ELFMAG0
326 && header
->e_ident
[EI_MAG1
] == ELFMAG1
327 && header
->e_ident
[EI_MAG2
] == ELFMAG2
328 && header
->e_ident
[EI_MAG3
] == ELFMAG3
)
330 *machine
= header
->e_machine
;
331 return header
->e_ident
[EI_CLASS
] == ELFCLASS64
;
338 /* Return non-zero if FILE is a 64-bit ELF file,
339 zero if the file is not a 64-bit ELF file,
340 and -1 if the file is not accessible or doesn't exist. */
343 elf_64_file_p (const char *file
, unsigned int *machine
)
348 fd
= open (file
, O_RDONLY
);
352 if (read (fd
, &header
, sizeof (header
)) != sizeof (header
))
359 return elf_64_header_p (&header
, machine
);
362 /* Accepts an integer PID; Returns true if the executable PID is
363 running is a 64-bit ELF file.. */
366 linux_pid_exe_is_elf_64_file (int pid
, unsigned int *machine
)
370 sprintf (file
, "/proc/%d/exe", pid
);
371 return elf_64_file_p (file
, machine
);
375 linux_process_target::delete_lwp (lwp_info
*lwp
)
377 struct thread_info
*thr
= get_lwp_thread (lwp
);
380 debug_printf ("deleting %ld\n", lwpid_of (thr
));
384 low_delete_thread (lwp
->arch_private
);
390 linux_process_target::low_delete_thread (arch_lwp_info
*info
)
392 /* Default implementation should be overridden if architecture-specific
393 info is being used. */
394 gdb_assert (info
== nullptr);
398 linux_process_target::add_linux_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 proc
->priv
->arch_private
= low_new_process ();
411 linux_process_target::low_new_process ()
417 linux_process_target::low_delete_process (arch_process_info
*info
)
419 /* Default implementation must be overridden if architecture-specific
421 gdb_assert (info
== nullptr);
425 linux_process_target::low_new_fork (process_info
*parent
, process_info
*child
)
431 linux_process_target::arch_setup_thread (thread_info
*thread
)
433 struct thread_info
*saved_thread
;
435 saved_thread
= current_thread
;
436 current_thread
= thread
;
440 current_thread
= saved_thread
;
444 linux_process_target::handle_extended_wait (lwp_info
**orig_event_lwp
,
447 client_state
&cs
= get_client_state ();
448 struct lwp_info
*event_lwp
= *orig_event_lwp
;
449 int event
= linux_ptrace_get_extended_event (wstat
);
450 struct thread_info
*event_thr
= get_lwp_thread (event_lwp
);
451 struct lwp_info
*new_lwp
;
453 gdb_assert (event_lwp
->waitstatus
.kind
== TARGET_WAITKIND_IGNORE
);
455 /* All extended events we currently use are mid-syscall. Only
456 PTRACE_EVENT_STOP is delivered more like a signal-stop, but
457 you have to be using PTRACE_SEIZE to get that. */
458 event_lwp
->syscall_state
= TARGET_WAITKIND_SYSCALL_ENTRY
;
460 if ((event
== PTRACE_EVENT_FORK
) || (event
== PTRACE_EVENT_VFORK
)
461 || (event
== PTRACE_EVENT_CLONE
))
464 unsigned long new_pid
;
467 /* Get the pid of the new lwp. */
468 ptrace (PTRACE_GETEVENTMSG
, lwpid_of (event_thr
), (PTRACE_TYPE_ARG3
) 0,
471 /* If we haven't already seen the new PID stop, wait for it now. */
472 if (!pull_pid_from_list (&stopped_pids
, new_pid
, &status
))
474 /* The new child has a pending SIGSTOP. We can't affect it until it
475 hits the SIGSTOP, but we're already attached. */
477 ret
= my_waitpid (new_pid
, &status
, __WALL
);
480 perror_with_name ("waiting for new child");
481 else if (ret
!= new_pid
)
482 warning ("wait returned unexpected PID %d", ret
);
483 else if (!WIFSTOPPED (status
))
484 warning ("wait returned unexpected status 0x%x", status
);
487 if (event
== PTRACE_EVENT_FORK
|| event
== PTRACE_EVENT_VFORK
)
489 struct process_info
*parent_proc
;
490 struct process_info
*child_proc
;
491 struct lwp_info
*child_lwp
;
492 struct thread_info
*child_thr
;
494 ptid
= ptid_t (new_pid
, new_pid
, 0);
498 debug_printf ("HEW: Got fork event from LWP %ld, "
500 ptid_of (event_thr
).lwp (),
504 /* Add the new process to the tables and clone the breakpoint
505 lists of the parent. We need to do this even if the new process
506 will be detached, since we will need the process object and the
507 breakpoints to remove any breakpoints from memory when we
508 detach, and the client side will access registers. */
509 child_proc
= add_linux_process (new_pid
, 0);
510 gdb_assert (child_proc
!= NULL
);
511 child_lwp
= add_lwp (ptid
);
512 gdb_assert (child_lwp
!= NULL
);
513 child_lwp
->stopped
= 1;
514 child_lwp
->must_set_ptrace_flags
= 1;
515 child_lwp
->status_pending_p
= 0;
516 child_thr
= get_lwp_thread (child_lwp
);
517 child_thr
->last_resume_kind
= resume_stop
;
518 child_thr
->last_status
.kind
= TARGET_WAITKIND_STOPPED
;
520 /* If we're suspending all threads, leave this one suspended
521 too. If the fork/clone parent is stepping over a breakpoint,
522 all other threads have been suspended already. Leave the
523 child suspended too. */
524 if (stopping_threads
== STOPPING_AND_SUSPENDING_THREADS
525 || event_lwp
->bp_reinsert
!= 0)
528 debug_printf ("HEW: leaving child suspended\n");
529 child_lwp
->suspended
= 1;
532 parent_proc
= get_thread_process (event_thr
);
533 child_proc
->attached
= parent_proc
->attached
;
535 if (event_lwp
->bp_reinsert
!= 0
536 && supports_software_single_step ()
537 && event
== PTRACE_EVENT_VFORK
)
539 /* If we leave single-step breakpoints there, child will
540 hit it, so uninsert single-step breakpoints from parent
541 (and child). Once vfork child is done, reinsert
542 them back to parent. */
543 uninsert_single_step_breakpoints (event_thr
);
546 clone_all_breakpoints (child_thr
, event_thr
);
548 target_desc_up tdesc
= allocate_target_description ();
549 copy_target_description (tdesc
.get (), parent_proc
->tdesc
);
550 child_proc
->tdesc
= tdesc
.release ();
552 /* Clone arch-specific process data. */
553 low_new_fork (parent_proc
, child_proc
);
555 /* Save fork info in the parent thread. */
556 if (event
== PTRACE_EVENT_FORK
)
557 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_FORKED
;
558 else if (event
== PTRACE_EVENT_VFORK
)
559 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_VFORKED
;
561 event_lwp
->waitstatus
.value
.related_pid
= ptid
;
563 /* The status_pending field contains bits denoting the
564 extended event, so when the pending event is handled,
565 the handler will look at lwp->waitstatus. */
566 event_lwp
->status_pending_p
= 1;
567 event_lwp
->status_pending
= wstat
;
569 /* Link the threads until the parent event is passed on to
571 event_lwp
->fork_relative
= child_lwp
;
572 child_lwp
->fork_relative
= event_lwp
;
574 /* If the parent thread is doing step-over with single-step
575 breakpoints, the list of single-step breakpoints are cloned
576 from the parent's. Remove them from the child process.
577 In case of vfork, we'll reinsert them back once vforked
579 if (event_lwp
->bp_reinsert
!= 0
580 && supports_software_single_step ())
582 /* The child process is forked and stopped, so it is safe
583 to access its memory without stopping all other threads
584 from other processes. */
585 delete_single_step_breakpoints (child_thr
);
587 gdb_assert (has_single_step_breakpoints (event_thr
));
588 gdb_assert (!has_single_step_breakpoints (child_thr
));
591 /* Report the event. */
596 debug_printf ("HEW: Got clone event "
597 "from LWP %ld, new child is LWP %ld\n",
598 lwpid_of (event_thr
), new_pid
);
600 ptid
= ptid_t (pid_of (event_thr
), new_pid
, 0);
601 new_lwp
= add_lwp (ptid
);
603 /* Either we're going to immediately resume the new thread
604 or leave it stopped. resume_one_lwp is a nop if it
605 thinks the thread is currently running, so set this first
606 before calling resume_one_lwp. */
607 new_lwp
->stopped
= 1;
609 /* If we're suspending all threads, leave this one suspended
610 too. If the fork/clone parent is stepping over a breakpoint,
611 all other threads have been suspended already. Leave the
612 child suspended too. */
613 if (stopping_threads
== STOPPING_AND_SUSPENDING_THREADS
614 || event_lwp
->bp_reinsert
!= 0)
615 new_lwp
->suspended
= 1;
617 /* Normally we will get the pending SIGSTOP. But in some cases
618 we might get another signal delivered to the group first.
619 If we do get another signal, be sure not to lose it. */
620 if (WSTOPSIG (status
) != SIGSTOP
)
622 new_lwp
->stop_expected
= 1;
623 new_lwp
->status_pending_p
= 1;
624 new_lwp
->status_pending
= status
;
626 else if (cs
.report_thread_events
)
628 new_lwp
->waitstatus
.kind
= TARGET_WAITKIND_THREAD_CREATED
;
629 new_lwp
->status_pending_p
= 1;
630 new_lwp
->status_pending
= status
;
634 thread_db_notice_clone (event_thr
, ptid
);
637 /* Don't report the event. */
640 else if (event
== PTRACE_EVENT_VFORK_DONE
)
642 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_VFORK_DONE
;
644 if (event_lwp
->bp_reinsert
!= 0 && supports_software_single_step ())
646 reinsert_single_step_breakpoints (event_thr
);
648 gdb_assert (has_single_step_breakpoints (event_thr
));
651 /* Report the event. */
654 else if (event
== PTRACE_EVENT_EXEC
&& cs
.report_exec_events
)
656 struct process_info
*proc
;
657 std::vector
<int> syscalls_to_catch
;
663 debug_printf ("HEW: Got exec event from LWP %ld\n",
664 lwpid_of (event_thr
));
667 /* Get the event ptid. */
668 event_ptid
= ptid_of (event_thr
);
669 event_pid
= event_ptid
.pid ();
671 /* Save the syscall list from the execing process. */
672 proc
= get_thread_process (event_thr
);
673 syscalls_to_catch
= std::move (proc
->syscalls_to_catch
);
675 /* Delete the execing process and all its threads. */
677 current_thread
= NULL
;
679 /* Create a new process/lwp/thread. */
680 proc
= add_linux_process (event_pid
, 0);
681 event_lwp
= add_lwp (event_ptid
);
682 event_thr
= get_lwp_thread (event_lwp
);
683 gdb_assert (current_thread
== event_thr
);
684 arch_setup_thread (event_thr
);
686 /* Set the event status. */
687 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_EXECD
;
688 event_lwp
->waitstatus
.value
.execd_pathname
689 = xstrdup (linux_proc_pid_to_exec_file (lwpid_of (event_thr
)));
691 /* Mark the exec status as pending. */
692 event_lwp
->stopped
= 1;
693 event_lwp
->status_pending_p
= 1;
694 event_lwp
->status_pending
= wstat
;
695 event_thr
->last_resume_kind
= resume_continue
;
696 event_thr
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
698 /* Update syscall state in the new lwp, effectively mid-syscall too. */
699 event_lwp
->syscall_state
= TARGET_WAITKIND_SYSCALL_ENTRY
;
701 /* Restore the list to catch. Don't rely on the client, which is free
702 to avoid sending a new list when the architecture doesn't change.
703 Also, for ANY_SYSCALL, the architecture doesn't really matter. */
704 proc
->syscalls_to_catch
= std::move (syscalls_to_catch
);
706 /* Report the event. */
707 *orig_event_lwp
= event_lwp
;
711 internal_error (__FILE__
, __LINE__
, _("unknown ptrace event %d"), event
);
715 linux_process_target::get_pc (lwp_info
*lwp
)
717 struct thread_info
*saved_thread
;
718 struct regcache
*regcache
;
721 if (!low_supports_breakpoints ())
724 saved_thread
= current_thread
;
725 current_thread
= get_lwp_thread (lwp
);
727 regcache
= get_thread_regcache (current_thread
, 1);
728 pc
= low_get_pc (regcache
);
731 debug_printf ("pc is 0x%lx\n", (long) pc
);
733 current_thread
= saved_thread
;
738 linux_process_target::get_syscall_trapinfo (lwp_info
*lwp
, int *sysno
)
740 struct thread_info
*saved_thread
;
741 struct regcache
*regcache
;
743 saved_thread
= current_thread
;
744 current_thread
= get_lwp_thread (lwp
);
746 regcache
= get_thread_regcache (current_thread
, 1);
747 low_get_syscall_trapinfo (regcache
, sysno
);
750 debug_printf ("get_syscall_trapinfo sysno %d\n", *sysno
);
752 current_thread
= saved_thread
;
756 linux_process_target::low_get_syscall_trapinfo (regcache
*regcache
, int *sysno
)
758 /* By default, report an unknown system call number. */
759 *sysno
= UNKNOWN_SYSCALL
;
763 linux_process_target::save_stop_reason (lwp_info
*lwp
)
766 CORE_ADDR sw_breakpoint_pc
;
767 struct thread_info
*saved_thread
;
768 #if USE_SIGTRAP_SIGINFO
772 if (!low_supports_breakpoints ())
776 sw_breakpoint_pc
= pc
- low_decr_pc_after_break ();
778 /* breakpoint_at reads from the current thread. */
779 saved_thread
= current_thread
;
780 current_thread
= get_lwp_thread (lwp
);
782 #if USE_SIGTRAP_SIGINFO
783 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
784 (PTRACE_TYPE_ARG3
) 0, &siginfo
) == 0)
786 if (siginfo
.si_signo
== SIGTRAP
)
788 if (GDB_ARCH_IS_TRAP_BRKPT (siginfo
.si_code
)
789 && GDB_ARCH_IS_TRAP_HWBKPT (siginfo
.si_code
))
791 /* The si_code is ambiguous on this arch -- check debug
793 if (!check_stopped_by_watchpoint (lwp
))
794 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
796 else if (GDB_ARCH_IS_TRAP_BRKPT (siginfo
.si_code
))
798 /* If we determine the LWP stopped for a SW breakpoint,
799 trust it. Particularly don't check watchpoint
800 registers, because at least on s390, we'd find
801 stopped-by-watchpoint as long as there's a watchpoint
803 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
805 else if (GDB_ARCH_IS_TRAP_HWBKPT (siginfo
.si_code
))
807 /* This can indicate either a hardware breakpoint or
808 hardware watchpoint. Check debug registers. */
809 if (!check_stopped_by_watchpoint (lwp
))
810 lwp
->stop_reason
= TARGET_STOPPED_BY_HW_BREAKPOINT
;
812 else if (siginfo
.si_code
== TRAP_TRACE
)
814 /* We may have single stepped an instruction that
815 triggered a watchpoint. In that case, on some
816 architectures (such as x86), instead of TRAP_HWBKPT,
817 si_code indicates TRAP_TRACE, and we need to check
818 the debug registers separately. */
819 if (!check_stopped_by_watchpoint (lwp
))
820 lwp
->stop_reason
= TARGET_STOPPED_BY_SINGLE_STEP
;
825 /* We may have just stepped a breakpoint instruction. E.g., in
826 non-stop mode, GDB first tells the thread A to step a range, and
827 then the user inserts a breakpoint inside the range. In that
828 case we need to report the breakpoint PC. */
829 if ((!lwp
->stepping
|| lwp
->stop_pc
== sw_breakpoint_pc
)
830 && low_breakpoint_at (sw_breakpoint_pc
))
831 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
833 if (hardware_breakpoint_inserted_here (pc
))
834 lwp
->stop_reason
= TARGET_STOPPED_BY_HW_BREAKPOINT
;
836 if (lwp
->stop_reason
== TARGET_STOPPED_BY_NO_REASON
)
837 check_stopped_by_watchpoint (lwp
);
840 if (lwp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
)
844 struct thread_info
*thr
= get_lwp_thread (lwp
);
846 debug_printf ("CSBB: %s stopped by software breakpoint\n",
847 target_pid_to_str (ptid_of (thr
)));
850 /* Back up the PC if necessary. */
851 if (pc
!= sw_breakpoint_pc
)
853 struct regcache
*regcache
854 = get_thread_regcache (current_thread
, 1);
855 low_set_pc (regcache
, sw_breakpoint_pc
);
858 /* Update this so we record the correct stop PC below. */
859 pc
= sw_breakpoint_pc
;
861 else if (lwp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
)
865 struct thread_info
*thr
= get_lwp_thread (lwp
);
867 debug_printf ("CSBB: %s stopped by hardware breakpoint\n",
868 target_pid_to_str (ptid_of (thr
)));
871 else if (lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
)
875 struct thread_info
*thr
= get_lwp_thread (lwp
);
877 debug_printf ("CSBB: %s stopped by hardware watchpoint\n",
878 target_pid_to_str (ptid_of (thr
)));
881 else if (lwp
->stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
)
885 struct thread_info
*thr
= get_lwp_thread (lwp
);
887 debug_printf ("CSBB: %s stopped by trace\n",
888 target_pid_to_str (ptid_of (thr
)));
893 current_thread
= saved_thread
;
898 linux_process_target::add_lwp (ptid_t ptid
)
900 lwp_info
*lwp
= new lwp_info
;
902 lwp
->thread
= add_thread (ptid
, lwp
);
904 low_new_thread (lwp
);
910 linux_process_target::low_new_thread (lwp_info
*info
)
915 /* Callback to be used when calling fork_inferior, responsible for
916 actually initiating the tracing of the inferior. */
921 if (ptrace (PTRACE_TRACEME
, 0, (PTRACE_TYPE_ARG3
) 0,
922 (PTRACE_TYPE_ARG4
) 0) < 0)
923 trace_start_error_with_name ("ptrace");
925 if (setpgid (0, 0) < 0)
926 trace_start_error_with_name ("setpgid");
928 /* If GDBserver is connected to gdb via stdio, redirect the inferior's
929 stdout to stderr so that inferior i/o doesn't corrupt the connection.
930 Also, redirect stdin to /dev/null. */
931 if (remote_connection_is_stdio ())
934 trace_start_error_with_name ("close");
935 if (open ("/dev/null", O_RDONLY
) < 0)
936 trace_start_error_with_name ("open");
938 trace_start_error_with_name ("dup2");
939 if (write (2, "stdin/stdout redirected\n",
940 sizeof ("stdin/stdout redirected\n") - 1) < 0)
942 /* Errors ignored. */;
947 /* Start an inferior process and returns its pid.
948 PROGRAM is the name of the program to be started, and PROGRAM_ARGS
949 are its arguments. */
952 linux_process_target::create_inferior (const char *program
,
953 const std::vector
<char *> &program_args
)
955 client_state
&cs
= get_client_state ();
956 struct lwp_info
*new_lwp
;
961 maybe_disable_address_space_randomization restore_personality
962 (cs
.disable_randomization
);
963 std::string str_program_args
= construct_inferior_arguments (program_args
);
965 pid
= fork_inferior (program
,
966 str_program_args
.c_str (),
967 get_environ ()->envp (), linux_ptrace_fun
,
968 NULL
, NULL
, NULL
, NULL
);
971 add_linux_process (pid
, 0);
973 ptid
= ptid_t (pid
, pid
, 0);
974 new_lwp
= add_lwp (ptid
);
975 new_lwp
->must_set_ptrace_flags
= 1;
977 post_fork_inferior (pid
, program
);
982 /* Implement the post_create_inferior target_ops method. */
985 linux_process_target::post_create_inferior ()
987 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
991 if (lwp
->must_set_ptrace_flags
)
993 struct process_info
*proc
= current_process ();
994 int options
= linux_low_ptrace_options (proc
->attached
);
996 linux_enable_event_reporting (lwpid_of (current_thread
), options
);
997 lwp
->must_set_ptrace_flags
= 0;
1002 linux_process_target::attach_lwp (ptid_t ptid
)
1004 struct lwp_info
*new_lwp
;
1005 int lwpid
= ptid
.lwp ();
1007 if (ptrace (PTRACE_ATTACH
, lwpid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0)
1011 new_lwp
= add_lwp (ptid
);
1013 /* We need to wait for SIGSTOP before being able to make the next
1014 ptrace call on this LWP. */
1015 new_lwp
->must_set_ptrace_flags
= 1;
1017 if (linux_proc_pid_is_stopped (lwpid
))
1020 debug_printf ("Attached to a stopped process\n");
1022 /* The process is definitely stopped. It is in a job control
1023 stop, unless the kernel predates the TASK_STOPPED /
1024 TASK_TRACED distinction, in which case it might be in a
1025 ptrace stop. Make sure it is in a ptrace stop; from there we
1026 can kill it, signal it, et cetera.
1028 First make sure there is a pending SIGSTOP. Since we are
1029 already attached, the process can not transition from stopped
1030 to running without a PTRACE_CONT; so we know this signal will
1031 go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
1032 probably already in the queue (unless this kernel is old
1033 enough to use TASK_STOPPED for ptrace stops); but since
1034 SIGSTOP is not an RT signal, it can only be queued once. */
1035 kill_lwp (lwpid
, SIGSTOP
);
1037 /* Finally, resume the stopped process. This will deliver the
1038 SIGSTOP (or a higher priority signal, just like normal
1039 PTRACE_ATTACH), which we'll catch later on. */
1040 ptrace (PTRACE_CONT
, lwpid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
1043 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
1044 brings it to a halt.
1046 There are several cases to consider here:
1048 1) gdbserver has already attached to the process and is being notified
1049 of a new thread that is being created.
1050 In this case we should ignore that SIGSTOP and resume the
1051 process. This is handled below by setting stop_expected = 1,
1052 and the fact that add_thread sets last_resume_kind ==
1055 2) This is the first thread (the process thread), and we're attaching
1056 to it via attach_inferior.
1057 In this case we want the process thread to stop.
1058 This is handled by having linux_attach set last_resume_kind ==
1059 resume_stop after we return.
1061 If the pid we are attaching to is also the tgid, we attach to and
1062 stop all the existing threads. Otherwise, we attach to pid and
1063 ignore any other threads in the same group as this pid.
1065 3) GDB is connecting to gdbserver and is requesting an enumeration of all
1067 In this case we want the thread to stop.
1068 FIXME: This case is currently not properly handled.
1069 We should wait for the SIGSTOP but don't. Things work apparently
1070 because enough time passes between when we ptrace (ATTACH) and when
1071 gdb makes the next ptrace call on the thread.
1073 On the other hand, if we are currently trying to stop all threads, we
1074 should treat the new thread as if we had sent it a SIGSTOP. This works
1075 because we are guaranteed that the add_lwp call above added us to the
1076 end of the list, and so the new thread has not yet reached
1077 wait_for_sigstop (but will). */
1078 new_lwp
->stop_expected
= 1;
1083 /* Callback for linux_proc_attach_tgid_threads. Attach to PTID if not
1084 already attached. Returns true if a new LWP is found, false
1088 attach_proc_task_lwp_callback (ptid_t ptid
)
1090 /* Is this a new thread? */
1091 if (find_thread_ptid (ptid
) == NULL
)
1093 int lwpid
= ptid
.lwp ();
1097 debug_printf ("Found new lwp %d\n", lwpid
);
1099 err
= the_linux_target
->attach_lwp (ptid
);
1101 /* Be quiet if we simply raced with the thread exiting. EPERM
1102 is returned if the thread's task still exists, and is marked
1103 as exited or zombie, as well as other conditions, so in that
1104 case, confirm the status in /proc/PID/status. */
1106 || (err
== EPERM
&& linux_proc_pid_is_gone (lwpid
)))
1110 debug_printf ("Cannot attach to lwp %d: "
1111 "thread is gone (%d: %s)\n",
1112 lwpid
, err
, safe_strerror (err
));
1118 = linux_ptrace_attach_fail_reason_string (ptid
, err
);
1120 warning (_("Cannot attach to lwp %d: %s"), lwpid
, reason
.c_str ());
1128 static void async_file_mark (void);
1130 /* Attach to PID. If PID is the tgid, attach to it and all
1134 linux_process_target::attach (unsigned long pid
)
1136 struct process_info
*proc
;
1137 struct thread_info
*initial_thread
;
1138 ptid_t ptid
= ptid_t (pid
, pid
, 0);
1141 proc
= add_linux_process (pid
, 1);
1143 /* Attach to PID. We will check for other threads
1145 err
= attach_lwp (ptid
);
1148 remove_process (proc
);
1150 std::string reason
= linux_ptrace_attach_fail_reason_string (ptid
, err
);
1151 error ("Cannot attach to process %ld: %s", pid
, reason
.c_str ());
1154 /* Don't ignore the initial SIGSTOP if we just attached to this
1155 process. It will be collected by wait shortly. */
1156 initial_thread
= find_thread_ptid (ptid_t (pid
, pid
, 0));
1157 initial_thread
->last_resume_kind
= resume_stop
;
1159 /* We must attach to every LWP. If /proc is mounted, use that to
1160 find them now. On the one hand, the inferior may be using raw
1161 clone instead of using pthreads. On the other hand, even if it
1162 is using pthreads, GDB may not be connected yet (thread_db needs
1163 to do symbol lookups, through qSymbol). Also, thread_db walks
1164 structures in the inferior's address space to find the list of
1165 threads/LWPs, and those structures may well be corrupted. Note
1166 that once thread_db is loaded, we'll still use it to list threads
1167 and associate pthread info with each LWP. */
1168 linux_proc_attach_tgid_threads (pid
, attach_proc_task_lwp_callback
);
1170 /* GDB will shortly read the xml target description for this
1171 process, to figure out the process' architecture. But the target
1172 description is only filled in when the first process/thread in
1173 the thread group reports its initial PTRACE_ATTACH SIGSTOP. Do
1174 that now, otherwise, if GDB is fast enough, it could read the
1175 target description _before_ that initial stop. */
1178 struct lwp_info
*lwp
;
1180 ptid_t pid_ptid
= ptid_t (pid
);
1182 lwpid
= wait_for_event_filtered (pid_ptid
, pid_ptid
, &wstat
, __WALL
);
1183 gdb_assert (lwpid
> 0);
1185 lwp
= find_lwp_pid (ptid_t (lwpid
));
1187 if (!WIFSTOPPED (wstat
) || WSTOPSIG (wstat
) != SIGSTOP
)
1189 lwp
->status_pending_p
= 1;
1190 lwp
->status_pending
= wstat
;
1193 initial_thread
->last_resume_kind
= resume_continue
;
1197 gdb_assert (proc
->tdesc
!= NULL
);
1204 last_thread_of_process_p (int pid
)
1206 bool seen_one
= false;
1208 thread_info
*thread
= find_thread (pid
, [&] (thread_info
*thr_arg
)
1212 /* This is the first thread of this process we see. */
1218 /* This is the second thread of this process we see. */
1223 return thread
== NULL
;
1229 linux_kill_one_lwp (struct lwp_info
*lwp
)
1231 struct thread_info
*thr
= get_lwp_thread (lwp
);
1232 int pid
= lwpid_of (thr
);
1234 /* PTRACE_KILL is unreliable. After stepping into a signal handler,
1235 there is no signal context, and ptrace(PTRACE_KILL) (or
1236 ptrace(PTRACE_CONT, SIGKILL), pretty much the same) acts like
1237 ptrace(CONT, pid, 0,0) and just resumes the tracee. A better
1238 alternative is to kill with SIGKILL. We only need one SIGKILL
1239 per process, not one for each thread. But since we still support
1240 support debugging programs using raw clone without CLONE_THREAD,
1241 we send one for each thread. For years, we used PTRACE_KILL
1242 only, so we're being a bit paranoid about some old kernels where
1243 PTRACE_KILL might work better (dubious if there are any such, but
1244 that's why it's paranoia), so we try SIGKILL first, PTRACE_KILL
1245 second, and so we're fine everywhere. */
1248 kill_lwp (pid
, SIGKILL
);
1251 int save_errno
= errno
;
1253 debug_printf ("LKL: kill_lwp (SIGKILL) %s, 0, 0 (%s)\n",
1254 target_pid_to_str (ptid_of (thr
)),
1255 save_errno
? safe_strerror (save_errno
) : "OK");
1259 ptrace (PTRACE_KILL
, pid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
1262 int save_errno
= errno
;
1264 debug_printf ("LKL: PTRACE_KILL %s, 0, 0 (%s)\n",
1265 target_pid_to_str (ptid_of (thr
)),
1266 save_errno
? safe_strerror (save_errno
) : "OK");
1270 /* Kill LWP and wait for it to die. */
1273 kill_wait_lwp (struct lwp_info
*lwp
)
1275 struct thread_info
*thr
= get_lwp_thread (lwp
);
1276 int pid
= ptid_of (thr
).pid ();
1277 int lwpid
= ptid_of (thr
).lwp ();
1282 debug_printf ("kwl: killing lwp %d, for pid: %d\n", lwpid
, pid
);
1286 linux_kill_one_lwp (lwp
);
1288 /* Make sure it died. Notes:
1290 - The loop is most likely unnecessary.
1292 - We don't use wait_for_event as that could delete lwps
1293 while we're iterating over them. We're not interested in
1294 any pending status at this point, only in making sure all
1295 wait status on the kernel side are collected until the
1298 - We don't use __WALL here as the __WALL emulation relies on
1299 SIGCHLD, and killing a stopped process doesn't generate
1300 one, nor an exit status.
1302 res
= my_waitpid (lwpid
, &wstat
, 0);
1303 if (res
== -1 && errno
== ECHILD
)
1304 res
= my_waitpid (lwpid
, &wstat
, __WCLONE
);
1305 } while (res
> 0 && WIFSTOPPED (wstat
));
1307 /* Even if it was stopped, the child may have already disappeared.
1308 E.g., if it was killed by SIGKILL. */
1309 if (res
< 0 && errno
!= ECHILD
)
1310 perror_with_name ("kill_wait_lwp");
1313 /* Callback for `for_each_thread'. Kills an lwp of a given process,
1314 except the leader. */
1317 kill_one_lwp_callback (thread_info
*thread
, int pid
)
1319 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1321 /* We avoid killing the first thread here, because of a Linux kernel (at
1322 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
1323 the children get a chance to be reaped, it will remain a zombie
1326 if (lwpid_of (thread
) == pid
)
1329 debug_printf ("lkop: is last of process %s\n",
1330 target_pid_to_str (thread
->id
));
1334 kill_wait_lwp (lwp
);
1338 linux_process_target::kill (process_info
*process
)
1340 int pid
= process
->pid
;
1342 /* If we're killing a running inferior, make sure it is stopped
1343 first, as PTRACE_KILL will not work otherwise. */
1344 stop_all_lwps (0, NULL
);
1346 for_each_thread (pid
, [&] (thread_info
*thread
)
1348 kill_one_lwp_callback (thread
, pid
);
1351 /* See the comment in linux_kill_one_lwp. We did not kill the first
1352 thread in the list, so do so now. */
1353 lwp_info
*lwp
= find_lwp_pid (ptid_t (pid
));
1358 debug_printf ("lk_1: cannot find lwp for pid: %d\n",
1362 kill_wait_lwp (lwp
);
1366 /* Since we presently can only stop all lwps of all processes, we
1367 need to unstop lwps of other processes. */
1368 unstop_all_lwps (0, NULL
);
1372 /* Get pending signal of THREAD, for detaching purposes. This is the
1373 signal the thread last stopped for, which we need to deliver to the
1374 thread when detaching, otherwise, it'd be suppressed/lost. */
1377 get_detach_signal (struct thread_info
*thread
)
1379 client_state
&cs
= get_client_state ();
1380 enum gdb_signal signo
= GDB_SIGNAL_0
;
1382 struct lwp_info
*lp
= get_thread_lwp (thread
);
1384 if (lp
->status_pending_p
)
1385 status
= lp
->status_pending
;
1388 /* If the thread had been suspended by gdbserver, and it stopped
1389 cleanly, then it'll have stopped with SIGSTOP. But we don't
1390 want to deliver that SIGSTOP. */
1391 if (thread
->last_status
.kind
!= TARGET_WAITKIND_STOPPED
1392 || thread
->last_status
.value
.sig
== GDB_SIGNAL_0
)
1395 /* Otherwise, we may need to deliver the signal we
1397 status
= lp
->last_status
;
1400 if (!WIFSTOPPED (status
))
1403 debug_printf ("GPS: lwp %s hasn't stopped: no pending signal\n",
1404 target_pid_to_str (ptid_of (thread
)));
1408 /* Extended wait statuses aren't real SIGTRAPs. */
1409 if (WSTOPSIG (status
) == SIGTRAP
&& linux_is_extended_waitstatus (status
))
1412 debug_printf ("GPS: lwp %s had stopped with extended "
1413 "status: no pending signal\n",
1414 target_pid_to_str (ptid_of (thread
)));
1418 signo
= gdb_signal_from_host (WSTOPSIG (status
));
1420 if (cs
.program_signals_p
&& !cs
.program_signals
[signo
])
1423 debug_printf ("GPS: lwp %s had signal %s, but it is in nopass state\n",
1424 target_pid_to_str (ptid_of (thread
)),
1425 gdb_signal_to_string (signo
));
1428 else if (!cs
.program_signals_p
1429 /* If we have no way to know which signals GDB does not
1430 want to have passed to the program, assume
1431 SIGTRAP/SIGINT, which is GDB's default. */
1432 && (signo
== GDB_SIGNAL_TRAP
|| signo
== GDB_SIGNAL_INT
))
1435 debug_printf ("GPS: lwp %s had signal %s, "
1436 "but we don't know if we should pass it. "
1437 "Default to not.\n",
1438 target_pid_to_str (ptid_of (thread
)),
1439 gdb_signal_to_string (signo
));
1445 debug_printf ("GPS: lwp %s has pending signal %s: delivering it.\n",
1446 target_pid_to_str (ptid_of (thread
)),
1447 gdb_signal_to_string (signo
));
1449 return WSTOPSIG (status
);
1454 linux_process_target::detach_one_lwp (lwp_info
*lwp
)
1456 struct thread_info
*thread
= get_lwp_thread (lwp
);
1460 /* If there is a pending SIGSTOP, get rid of it. */
1461 if (lwp
->stop_expected
)
1464 debug_printf ("Sending SIGCONT to %s\n",
1465 target_pid_to_str (ptid_of (thread
)));
1467 kill_lwp (lwpid_of (thread
), SIGCONT
);
1468 lwp
->stop_expected
= 0;
1471 /* Pass on any pending signal for this thread. */
1472 sig
= get_detach_signal (thread
);
1474 /* Preparing to resume may try to write registers, and fail if the
1475 lwp is zombie. If that happens, ignore the error. We'll handle
1476 it below, when detach fails with ESRCH. */
1479 /* Flush any pending changes to the process's registers. */
1480 regcache_invalidate_thread (thread
);
1482 /* Finally, let it resume. */
1483 low_prepare_to_resume (lwp
);
1485 catch (const gdb_exception_error
&ex
)
1487 if (!check_ptrace_stopped_lwp_gone (lwp
))
1491 lwpid
= lwpid_of (thread
);
1492 if (ptrace (PTRACE_DETACH
, lwpid
, (PTRACE_TYPE_ARG3
) 0,
1493 (PTRACE_TYPE_ARG4
) (long) sig
) < 0)
1495 int save_errno
= errno
;
1497 /* We know the thread exists, so ESRCH must mean the lwp is
1498 zombie. This can happen if one of the already-detached
1499 threads exits the whole thread group. In that case we're
1500 still attached, and must reap the lwp. */
1501 if (save_errno
== ESRCH
)
1505 ret
= my_waitpid (lwpid
, &status
, __WALL
);
1508 warning (_("Couldn't reap LWP %d while detaching: %s"),
1509 lwpid
, safe_strerror (errno
));
1511 else if (!WIFEXITED (status
) && !WIFSIGNALED (status
))
1513 warning (_("Reaping LWP %d while detaching "
1514 "returned unexpected status 0x%x"),
1520 error (_("Can't detach %s: %s"),
1521 target_pid_to_str (ptid_of (thread
)),
1522 safe_strerror (save_errno
));
1525 else if (debug_threads
)
1527 debug_printf ("PTRACE_DETACH (%s, %s, 0) (OK)\n",
1528 target_pid_to_str (ptid_of (thread
)),
1536 linux_process_target::detach (process_info
*process
)
1538 struct lwp_info
*main_lwp
;
1540 /* As there's a step over already in progress, let it finish first,
1541 otherwise nesting a stabilize_threads operation on top gets real
1543 complete_ongoing_step_over ();
1545 /* Stop all threads before detaching. First, ptrace requires that
1546 the thread is stopped to successfully detach. Second, thread_db
1547 may need to uninstall thread event breakpoints from memory, which
1548 only works with a stopped process anyway. */
1549 stop_all_lwps (0, NULL
);
1551 #ifdef USE_THREAD_DB
1552 thread_db_detach (process
);
1555 /* Stabilize threads (move out of jump pads). */
1556 target_stabilize_threads ();
1558 /* Detach from the clone lwps first. If the thread group exits just
1559 while we're detaching, we must reap the clone lwps before we're
1560 able to reap the leader. */
1561 for_each_thread (process
->pid
, [this] (thread_info
*thread
)
1563 /* We don't actually detach from the thread group leader just yet.
1564 If the thread group exits, we must reap the zombie clone lwps
1565 before we're able to reap the leader. */
1566 if (thread
->id
.pid () == thread
->id
.lwp ())
1569 lwp_info
*lwp
= get_thread_lwp (thread
);
1570 detach_one_lwp (lwp
);
1573 main_lwp
= find_lwp_pid (ptid_t (process
->pid
));
1574 detach_one_lwp (main_lwp
);
1578 /* Since we presently can only stop all lwps of all processes, we
1579 need to unstop lwps of other processes. */
1580 unstop_all_lwps (0, NULL
);
1584 /* Remove all LWPs that belong to process PROC from the lwp list. */
1587 linux_process_target::mourn (process_info
*process
)
1589 struct process_info_private
*priv
;
1591 #ifdef USE_THREAD_DB
1592 thread_db_mourn (process
);
1595 for_each_thread (process
->pid
, [this] (thread_info
*thread
)
1597 delete_lwp (get_thread_lwp (thread
));
1600 /* Freeing all private data. */
1601 priv
= process
->priv
;
1602 low_delete_process (priv
->arch_private
);
1604 process
->priv
= NULL
;
1606 remove_process (process
);
1610 linux_process_target::join (int pid
)
1615 ret
= my_waitpid (pid
, &status
, 0);
1616 if (WIFEXITED (status
) || WIFSIGNALED (status
))
1618 } while (ret
!= -1 || errno
!= ECHILD
);
1621 /* Return true if the given thread is still alive. */
1624 linux_process_target::thread_alive (ptid_t ptid
)
1626 struct lwp_info
*lwp
= find_lwp_pid (ptid
);
1628 /* We assume we always know if a thread exits. If a whole process
1629 exited but we still haven't been able to report it to GDB, we'll
1630 hold on to the last lwp of the dead process. */
1632 return !lwp_is_marked_dead (lwp
);
1638 linux_process_target::thread_still_has_status_pending (thread_info
*thread
)
1640 struct lwp_info
*lp
= get_thread_lwp (thread
);
1642 if (!lp
->status_pending_p
)
1645 if (thread
->last_resume_kind
!= resume_stop
1646 && (lp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
1647 || lp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
1649 struct thread_info
*saved_thread
;
1653 gdb_assert (lp
->last_status
!= 0);
1657 saved_thread
= current_thread
;
1658 current_thread
= thread
;
1660 if (pc
!= lp
->stop_pc
)
1663 debug_printf ("PC of %ld changed\n",
1668 #if !USE_SIGTRAP_SIGINFO
1669 else if (lp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
1670 && !low_breakpoint_at (pc
))
1673 debug_printf ("previous SW breakpoint of %ld gone\n",
1677 else if (lp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
1678 && !hardware_breakpoint_inserted_here (pc
))
1681 debug_printf ("previous HW breakpoint of %ld gone\n",
1687 current_thread
= saved_thread
;
1692 debug_printf ("discarding pending breakpoint status\n");
1693 lp
->status_pending_p
= 0;
1701 /* Returns true if LWP is resumed from the client's perspective. */
1704 lwp_resumed (struct lwp_info
*lwp
)
1706 struct thread_info
*thread
= get_lwp_thread (lwp
);
1708 if (thread
->last_resume_kind
!= resume_stop
)
1711 /* Did gdb send us a `vCont;t', but we haven't reported the
1712 corresponding stop to gdb yet? If so, the thread is still
1713 resumed/running from gdb's perspective. */
1714 if (thread
->last_resume_kind
== resume_stop
1715 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
)
1722 linux_process_target::status_pending_p_callback (thread_info
*thread
,
1725 struct lwp_info
*lp
= get_thread_lwp (thread
);
1727 /* Check if we're only interested in events from a specific process
1728 or a specific LWP. */
1729 if (!thread
->id
.matches (ptid
))
1732 if (!lwp_resumed (lp
))
1735 if (lp
->status_pending_p
1736 && !thread_still_has_status_pending (thread
))
1738 resume_one_lwp (lp
, lp
->stepping
, GDB_SIGNAL_0
, NULL
);
1742 return lp
->status_pending_p
;
1746 find_lwp_pid (ptid_t ptid
)
1748 thread_info
*thread
= find_thread ([&] (thread_info
*thr_arg
)
1750 int lwp
= ptid
.lwp () != 0 ? ptid
.lwp () : ptid
.pid ();
1751 return thr_arg
->id
.lwp () == lwp
;
1757 return get_thread_lwp (thread
);
1760 /* Return the number of known LWPs in the tgid given by PID. */
1767 for_each_thread (pid
, [&] (thread_info
*thread
)
1775 /* See nat/linux-nat.h. */
1778 iterate_over_lwps (ptid_t filter
,
1779 gdb::function_view
<iterate_over_lwps_ftype
> callback
)
1781 thread_info
*thread
= find_thread (filter
, [&] (thread_info
*thr_arg
)
1783 lwp_info
*lwp
= get_thread_lwp (thr_arg
);
1785 return callback (lwp
);
1791 return get_thread_lwp (thread
);
1795 linux_process_target::check_zombie_leaders ()
1797 for_each_process ([this] (process_info
*proc
) {
1798 pid_t leader_pid
= pid_of (proc
);
1799 struct lwp_info
*leader_lp
;
1801 leader_lp
= find_lwp_pid (ptid_t (leader_pid
));
1804 debug_printf ("leader_pid=%d, leader_lp!=NULL=%d, "
1805 "num_lwps=%d, zombie=%d\n",
1806 leader_pid
, leader_lp
!= NULL
, num_lwps (leader_pid
),
1807 linux_proc_pid_is_zombie (leader_pid
));
1809 if (leader_lp
!= NULL
&& !leader_lp
->stopped
1810 /* Check if there are other threads in the group, as we may
1811 have raced with the inferior simply exiting. */
1812 && !last_thread_of_process_p (leader_pid
)
1813 && linux_proc_pid_is_zombie (leader_pid
))
1815 /* A leader zombie can mean one of two things:
1817 - It exited, and there's an exit status pending
1818 available, or only the leader exited (not the whole
1819 program). In the latter case, we can't waitpid the
1820 leader's exit status until all other threads are gone.
1822 - There are 3 or more threads in the group, and a thread
1823 other than the leader exec'd. On an exec, the Linux
1824 kernel destroys all other threads (except the execing
1825 one) in the thread group, and resets the execing thread's
1826 tid to the tgid. No exit notification is sent for the
1827 execing thread -- from the ptracer's perspective, it
1828 appears as though the execing thread just vanishes.
1829 Until we reap all other threads except the leader and the
1830 execing thread, the leader will be zombie, and the
1831 execing thread will be in `D (disc sleep)'. As soon as
1832 all other threads are reaped, the execing thread changes
1833 it's tid to the tgid, and the previous (zombie) leader
1834 vanishes, giving place to the "new" leader. We could try
1835 distinguishing the exit and exec cases, by waiting once
1836 more, and seeing if something comes out, but it doesn't
1837 sound useful. The previous leader _does_ go away, and
1838 we'll re-add the new one once we see the exec event
1839 (which is just the same as what would happen if the
1840 previous leader did exit voluntarily before some other
1844 debug_printf ("CZL: Thread group leader %d zombie "
1845 "(it exited, or another thread execd).\n",
1848 delete_lwp (leader_lp
);
1853 /* Callback for `find_thread'. Returns the first LWP that is not
1857 not_stopped_callback (thread_info
*thread
, ptid_t filter
)
1859 if (!thread
->id
.matches (filter
))
1862 lwp_info
*lwp
= get_thread_lwp (thread
);
1864 return !lwp
->stopped
;
1867 /* Increment LWP's suspend count. */
1870 lwp_suspended_inc (struct lwp_info
*lwp
)
1874 if (debug_threads
&& lwp
->suspended
> 4)
1876 struct thread_info
*thread
= get_lwp_thread (lwp
);
1878 debug_printf ("LWP %ld has a suspiciously high suspend count,"
1879 " suspended=%d\n", lwpid_of (thread
), lwp
->suspended
);
1883 /* Decrement LWP's suspend count. */
1886 lwp_suspended_decr (struct lwp_info
*lwp
)
1890 if (lwp
->suspended
< 0)
1892 struct thread_info
*thread
= get_lwp_thread (lwp
);
1894 internal_error (__FILE__
, __LINE__
,
1895 "unsuspend LWP %ld, suspended=%d\n", lwpid_of (thread
),
1900 /* This function should only be called if the LWP got a SIGTRAP.
1902 Handle any tracepoint steps or hits. Return true if a tracepoint
1903 event was handled, 0 otherwise. */
1906 handle_tracepoints (struct lwp_info
*lwp
)
1908 struct thread_info
*tinfo
= get_lwp_thread (lwp
);
1909 int tpoint_related_event
= 0;
1911 gdb_assert (lwp
->suspended
== 0);
1913 /* If this tracepoint hit causes a tracing stop, we'll immediately
1914 uninsert tracepoints. To do this, we temporarily pause all
1915 threads, unpatch away, and then unpause threads. We need to make
1916 sure the unpausing doesn't resume LWP too. */
1917 lwp_suspended_inc (lwp
);
1919 /* And we need to be sure that any all-threads-stopping doesn't try
1920 to move threads out of the jump pads, as it could deadlock the
1921 inferior (LWP could be in the jump pad, maybe even holding the
1924 /* Do any necessary step collect actions. */
1925 tpoint_related_event
|= tracepoint_finished_step (tinfo
, lwp
->stop_pc
);
1927 tpoint_related_event
|= handle_tracepoint_bkpts (tinfo
, lwp
->stop_pc
);
1929 /* See if we just hit a tracepoint and do its main collect
1931 tpoint_related_event
|= tracepoint_was_hit (tinfo
, lwp
->stop_pc
);
1933 lwp_suspended_decr (lwp
);
1935 gdb_assert (lwp
->suspended
== 0);
1936 gdb_assert (!stabilizing_threads
1937 || (lwp
->collecting_fast_tracepoint
1938 != fast_tpoint_collect_result::not_collecting
));
1940 if (tpoint_related_event
)
1943 debug_printf ("got a tracepoint event\n");
1950 fast_tpoint_collect_result
1951 linux_process_target::linux_fast_tracepoint_collecting
1952 (lwp_info
*lwp
, fast_tpoint_collect_status
*status
)
1954 CORE_ADDR thread_area
;
1955 struct thread_info
*thread
= get_lwp_thread (lwp
);
1957 /* Get the thread area address. This is used to recognize which
1958 thread is which when tracing with the in-process agent library.
1959 We don't read anything from the address, and treat it as opaque;
1960 it's the address itself that we assume is unique per-thread. */
1961 if (low_get_thread_area (lwpid_of (thread
), &thread_area
) == -1)
1962 return fast_tpoint_collect_result::not_collecting
;
1964 return fast_tracepoint_collecting (thread_area
, lwp
->stop_pc
, status
);
1968 linux_process_target::low_get_thread_area (int lwpid
, CORE_ADDR
*addrp
)
1974 linux_process_target::maybe_move_out_of_jump_pad (lwp_info
*lwp
, int *wstat
)
1976 struct thread_info
*saved_thread
;
1978 saved_thread
= current_thread
;
1979 current_thread
= get_lwp_thread (lwp
);
1982 || (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) != SIGTRAP
))
1983 && supports_fast_tracepoints ()
1984 && agent_loaded_p ())
1986 struct fast_tpoint_collect_status status
;
1989 debug_printf ("Checking whether LWP %ld needs to move out of the "
1991 lwpid_of (current_thread
));
1993 fast_tpoint_collect_result r
1994 = linux_fast_tracepoint_collecting (lwp
, &status
);
1997 || (WSTOPSIG (*wstat
) != SIGILL
1998 && WSTOPSIG (*wstat
) != SIGFPE
1999 && WSTOPSIG (*wstat
) != SIGSEGV
2000 && WSTOPSIG (*wstat
) != SIGBUS
))
2002 lwp
->collecting_fast_tracepoint
= r
;
2004 if (r
!= fast_tpoint_collect_result::not_collecting
)
2006 if (r
== fast_tpoint_collect_result::before_insn
2007 && lwp
->exit_jump_pad_bkpt
== NULL
)
2009 /* Haven't executed the original instruction yet.
2010 Set breakpoint there, and wait till it's hit,
2011 then single-step until exiting the jump pad. */
2012 lwp
->exit_jump_pad_bkpt
2013 = set_breakpoint_at (status
.adjusted_insn_addr
, NULL
);
2017 debug_printf ("Checking whether LWP %ld needs to move out of "
2018 "the jump pad...it does\n",
2019 lwpid_of (current_thread
));
2020 current_thread
= saved_thread
;
2027 /* If we get a synchronous signal while collecting, *and*
2028 while executing the (relocated) original instruction,
2029 reset the PC to point at the tpoint address, before
2030 reporting to GDB. Otherwise, it's an IPA lib bug: just
2031 report the signal to GDB, and pray for the best. */
2033 lwp
->collecting_fast_tracepoint
2034 = fast_tpoint_collect_result::not_collecting
;
2036 if (r
!= fast_tpoint_collect_result::not_collecting
2037 && (status
.adjusted_insn_addr
<= lwp
->stop_pc
2038 && lwp
->stop_pc
< status
.adjusted_insn_addr_end
))
2041 struct regcache
*regcache
;
2043 /* The si_addr on a few signals references the address
2044 of the faulting instruction. Adjust that as
2046 if ((WSTOPSIG (*wstat
) == SIGILL
2047 || WSTOPSIG (*wstat
) == SIGFPE
2048 || WSTOPSIG (*wstat
) == SIGBUS
2049 || WSTOPSIG (*wstat
) == SIGSEGV
)
2050 && ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
2051 (PTRACE_TYPE_ARG3
) 0, &info
) == 0
2052 /* Final check just to make sure we don't clobber
2053 the siginfo of non-kernel-sent signals. */
2054 && (uintptr_t) info
.si_addr
== lwp
->stop_pc
)
2056 info
.si_addr
= (void *) (uintptr_t) status
.tpoint_addr
;
2057 ptrace (PTRACE_SETSIGINFO
, lwpid_of (current_thread
),
2058 (PTRACE_TYPE_ARG3
) 0, &info
);
2061 regcache
= get_thread_regcache (current_thread
, 1);
2062 low_set_pc (regcache
, status
.tpoint_addr
);
2063 lwp
->stop_pc
= status
.tpoint_addr
;
2065 /* Cancel any fast tracepoint lock this thread was
2067 force_unlock_trace_buffer ();
2070 if (lwp
->exit_jump_pad_bkpt
!= NULL
)
2073 debug_printf ("Cancelling fast exit-jump-pad: removing bkpt. "
2074 "stopping all threads momentarily.\n");
2076 stop_all_lwps (1, lwp
);
2078 delete_breakpoint (lwp
->exit_jump_pad_bkpt
);
2079 lwp
->exit_jump_pad_bkpt
= NULL
;
2081 unstop_all_lwps (1, lwp
);
2083 gdb_assert (lwp
->suspended
>= 0);
2089 debug_printf ("Checking whether LWP %ld needs to move out of the "
2091 lwpid_of (current_thread
));
2093 current_thread
= saved_thread
;
2097 /* Enqueue one signal in the "signals to report later when out of the
2101 enqueue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
2103 struct thread_info
*thread
= get_lwp_thread (lwp
);
2106 debug_printf ("Deferring signal %d for LWP %ld.\n",
2107 WSTOPSIG (*wstat
), lwpid_of (thread
));
2111 for (const auto &sig
: lwp
->pending_signals_to_report
)
2112 debug_printf (" Already queued %d\n",
2115 debug_printf (" (no more currently queued signals)\n");
2118 /* Don't enqueue non-RT signals if they are already in the deferred
2119 queue. (SIGSTOP being the easiest signal to see ending up here
2121 if (WSTOPSIG (*wstat
) < __SIGRTMIN
)
2123 for (const auto &sig
: lwp
->pending_signals_to_report
)
2125 if (sig
.signal
== WSTOPSIG (*wstat
))
2128 debug_printf ("Not requeuing already queued non-RT signal %d"
2137 lwp
->pending_signals_to_report
.emplace_back (WSTOPSIG (*wstat
));
2139 ptrace (PTRACE_GETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
2140 &lwp
->pending_signals_to_report
.back ().info
);
2143 /* Dequeue one signal from the "signals to report later when out of
2144 the jump pad" list. */
2147 dequeue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
2149 struct thread_info
*thread
= get_lwp_thread (lwp
);
2151 if (!lwp
->pending_signals_to_report
.empty ())
2153 const pending_signal
&p_sig
= lwp
->pending_signals_to_report
.front ();
2155 *wstat
= W_STOPCODE (p_sig
.signal
);
2156 if (p_sig
.info
.si_signo
!= 0)
2157 ptrace (PTRACE_SETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
2160 lwp
->pending_signals_to_report
.pop_front ();
2163 debug_printf ("Reporting deferred signal %d for LWP %ld.\n",
2164 WSTOPSIG (*wstat
), lwpid_of (thread
));
2168 for (const auto &sig
: lwp
->pending_signals_to_report
)
2169 debug_printf (" Still queued %d\n",
2172 debug_printf (" (no more queued signals)\n");
2182 linux_process_target::check_stopped_by_watchpoint (lwp_info
*child
)
2184 struct thread_info
*saved_thread
= current_thread
;
2185 current_thread
= get_lwp_thread (child
);
2187 if (low_stopped_by_watchpoint ())
2189 child
->stop_reason
= TARGET_STOPPED_BY_WATCHPOINT
;
2190 child
->stopped_data_address
= low_stopped_data_address ();
2193 current_thread
= saved_thread
;
2195 return child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
;
2199 linux_process_target::low_stopped_by_watchpoint ()
2205 linux_process_target::low_stopped_data_address ()
2210 /* Return the ptrace options that we want to try to enable. */
2213 linux_low_ptrace_options (int attached
)
2215 client_state
&cs
= get_client_state ();
2219 options
|= PTRACE_O_EXITKILL
;
2221 if (cs
.report_fork_events
)
2222 options
|= PTRACE_O_TRACEFORK
;
2224 if (cs
.report_vfork_events
)
2225 options
|= (PTRACE_O_TRACEVFORK
| PTRACE_O_TRACEVFORKDONE
);
2227 if (cs
.report_exec_events
)
2228 options
|= PTRACE_O_TRACEEXEC
;
2230 options
|= PTRACE_O_TRACESYSGOOD
;
2236 linux_process_target::filter_event (int lwpid
, int wstat
)
2238 client_state
&cs
= get_client_state ();
2239 struct lwp_info
*child
;
2240 struct thread_info
*thread
;
2241 int have_stop_pc
= 0;
2243 child
= find_lwp_pid (ptid_t (lwpid
));
2245 /* Check for stop events reported by a process we didn't already
2246 know about - anything not already in our LWP list.
2248 If we're expecting to receive stopped processes after
2249 fork, vfork, and clone events, then we'll just add the
2250 new one to our list and go back to waiting for the event
2251 to be reported - the stopped process might be returned
2252 from waitpid before or after the event is.
2254 But note the case of a non-leader thread exec'ing after the
2255 leader having exited, and gone from our lists (because
2256 check_zombie_leaders deleted it). The non-leader thread
2257 changes its tid to the tgid. */
2259 if (WIFSTOPPED (wstat
) && child
== NULL
&& WSTOPSIG (wstat
) == SIGTRAP
2260 && linux_ptrace_get_extended_event (wstat
) == PTRACE_EVENT_EXEC
)
2264 /* A multi-thread exec after we had seen the leader exiting. */
2267 debug_printf ("LLW: Re-adding thread group leader LWP %d"
2268 "after exec.\n", lwpid
);
2271 child_ptid
= ptid_t (lwpid
, lwpid
, 0);
2272 child
= add_lwp (child_ptid
);
2274 current_thread
= child
->thread
;
2277 /* If we didn't find a process, one of two things presumably happened:
2278 - A process we started and then detached from has exited. Ignore it.
2279 - A process we are controlling has forked and the new child's stop
2280 was reported to us by the kernel. Save its PID. */
2281 if (child
== NULL
&& WIFSTOPPED (wstat
))
2283 add_to_pid_list (&stopped_pids
, lwpid
, wstat
);
2286 else if (child
== NULL
)
2289 thread
= get_lwp_thread (child
);
2293 child
->last_status
= wstat
;
2295 /* Check if the thread has exited. */
2296 if ((WIFEXITED (wstat
) || WIFSIGNALED (wstat
)))
2299 debug_printf ("LLFE: %d exited.\n", lwpid
);
2301 if (finish_step_over (child
))
2303 /* Unsuspend all other LWPs, and set them back running again. */
2304 unsuspend_all_lwps (child
);
2307 /* If there is at least one more LWP, then the exit signal was
2308 not the end of the debugged application and should be
2309 ignored, unless GDB wants to hear about thread exits. */
2310 if (cs
.report_thread_events
2311 || last_thread_of_process_p (pid_of (thread
)))
2313 /* Since events are serialized to GDB core, and we can't
2314 report this one right now. Leave the status pending for
2315 the next time we're able to report it. */
2316 mark_lwp_dead (child
, wstat
);
2326 gdb_assert (WIFSTOPPED (wstat
));
2328 if (WIFSTOPPED (wstat
))
2330 struct process_info
*proc
;
2332 /* Architecture-specific setup after inferior is running. */
2333 proc
= find_process_pid (pid_of (thread
));
2334 if (proc
->tdesc
== NULL
)
2338 /* This needs to happen after we have attached to the
2339 inferior and it is stopped for the first time, but
2340 before we access any inferior registers. */
2341 arch_setup_thread (thread
);
2345 /* The process is started, but GDBserver will do
2346 architecture-specific setup after the program stops at
2347 the first instruction. */
2348 child
->status_pending_p
= 1;
2349 child
->status_pending
= wstat
;
2355 if (WIFSTOPPED (wstat
) && child
->must_set_ptrace_flags
)
2357 struct process_info
*proc
= find_process_pid (pid_of (thread
));
2358 int options
= linux_low_ptrace_options (proc
->attached
);
2360 linux_enable_event_reporting (lwpid
, options
);
2361 child
->must_set_ptrace_flags
= 0;
2364 /* Always update syscall_state, even if it will be filtered later. */
2365 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SYSCALL_SIGTRAP
)
2367 child
->syscall_state
2368 = (child
->syscall_state
== TARGET_WAITKIND_SYSCALL_ENTRY
2369 ? TARGET_WAITKIND_SYSCALL_RETURN
2370 : TARGET_WAITKIND_SYSCALL_ENTRY
);
2374 /* Almost all other ptrace-stops are known to be outside of system
2375 calls, with further exceptions in handle_extended_wait. */
2376 child
->syscall_state
= TARGET_WAITKIND_IGNORE
;
2379 /* Be careful to not overwrite stop_pc until save_stop_reason is
2381 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGTRAP
2382 && linux_is_extended_waitstatus (wstat
))
2384 child
->stop_pc
= get_pc (child
);
2385 if (handle_extended_wait (&child
, wstat
))
2387 /* The event has been handled, so just return without
2393 if (linux_wstatus_maybe_breakpoint (wstat
))
2395 if (save_stop_reason (child
))
2400 child
->stop_pc
= get_pc (child
);
2402 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGSTOP
2403 && child
->stop_expected
)
2406 debug_printf ("Expected stop.\n");
2407 child
->stop_expected
= 0;
2409 if (thread
->last_resume_kind
== resume_stop
)
2411 /* We want to report the stop to the core. Treat the
2412 SIGSTOP as a normal event. */
2414 debug_printf ("LLW: resume_stop SIGSTOP caught for %s.\n",
2415 target_pid_to_str (ptid_of (thread
)));
2417 else if (stopping_threads
!= NOT_STOPPING_THREADS
)
2419 /* Stopping threads. We don't want this SIGSTOP to end up
2422 debug_printf ("LLW: SIGSTOP caught for %s "
2423 "while stopping threads.\n",
2424 target_pid_to_str (ptid_of (thread
)));
2429 /* This is a delayed SIGSTOP. Filter out the event. */
2431 debug_printf ("LLW: %s %s, 0, 0 (discard delayed SIGSTOP)\n",
2432 child
->stepping
? "step" : "continue",
2433 target_pid_to_str (ptid_of (thread
)));
2435 resume_one_lwp (child
, child
->stepping
, 0, NULL
);
2440 child
->status_pending_p
= 1;
2441 child
->status_pending
= wstat
;
2446 linux_process_target::maybe_hw_step (thread_info
*thread
)
2448 if (supports_hardware_single_step ())
2452 /* GDBserver must insert single-step breakpoint for software
2454 gdb_assert (has_single_step_breakpoints (thread
));
2460 linux_process_target::resume_stopped_resumed_lwps (thread_info
*thread
)
2462 struct lwp_info
*lp
= get_thread_lwp (thread
);
2466 && !lp
->status_pending_p
2467 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
)
2471 if (thread
->last_resume_kind
== resume_step
)
2472 step
= maybe_hw_step (thread
);
2475 debug_printf ("RSRL: resuming stopped-resumed LWP %s at %s: step=%d\n",
2476 target_pid_to_str (ptid_of (thread
)),
2477 paddress (lp
->stop_pc
),
2480 resume_one_lwp (lp
, step
, GDB_SIGNAL_0
, NULL
);
2485 linux_process_target::wait_for_event_filtered (ptid_t wait_ptid
,
2487 int *wstatp
, int options
)
2489 struct thread_info
*event_thread
;
2490 struct lwp_info
*event_child
, *requested_child
;
2491 sigset_t block_mask
, prev_mask
;
2494 /* N.B. event_thread points to the thread_info struct that contains
2495 event_child. Keep them in sync. */
2496 event_thread
= NULL
;
2498 requested_child
= NULL
;
2500 /* Check for a lwp with a pending status. */
2502 if (filter_ptid
== minus_one_ptid
|| filter_ptid
.is_pid ())
2504 event_thread
= find_thread_in_random ([&] (thread_info
*thread
)
2506 return status_pending_p_callback (thread
, filter_ptid
);
2509 if (event_thread
!= NULL
)
2510 event_child
= get_thread_lwp (event_thread
);
2511 if (debug_threads
&& event_thread
)
2512 debug_printf ("Got a pending child %ld\n", lwpid_of (event_thread
));
2514 else if (filter_ptid
!= null_ptid
)
2516 requested_child
= find_lwp_pid (filter_ptid
);
2518 if (stopping_threads
== NOT_STOPPING_THREADS
2519 && requested_child
->status_pending_p
2520 && (requested_child
->collecting_fast_tracepoint
2521 != fast_tpoint_collect_result::not_collecting
))
2523 enqueue_one_deferred_signal (requested_child
,
2524 &requested_child
->status_pending
);
2525 requested_child
->status_pending_p
= 0;
2526 requested_child
->status_pending
= 0;
2527 resume_one_lwp (requested_child
, 0, 0, NULL
);
2530 if (requested_child
->suspended
2531 && requested_child
->status_pending_p
)
2533 internal_error (__FILE__
, __LINE__
,
2534 "requesting an event out of a"
2535 " suspended child?");
2538 if (requested_child
->status_pending_p
)
2540 event_child
= requested_child
;
2541 event_thread
= get_lwp_thread (event_child
);
2545 if (event_child
!= NULL
)
2548 debug_printf ("Got an event from pending child %ld (%04x)\n",
2549 lwpid_of (event_thread
), event_child
->status_pending
);
2550 *wstatp
= event_child
->status_pending
;
2551 event_child
->status_pending_p
= 0;
2552 event_child
->status_pending
= 0;
2553 current_thread
= event_thread
;
2554 return lwpid_of (event_thread
);
2557 /* But if we don't find a pending event, we'll have to wait.
2559 We only enter this loop if no process has a pending wait status.
2560 Thus any action taken in response to a wait status inside this
2561 loop is responding as soon as we detect the status, not after any
2564 /* Make sure SIGCHLD is blocked until the sigsuspend below. Block
2565 all signals while here. */
2566 sigfillset (&block_mask
);
2567 gdb_sigmask (SIG_BLOCK
, &block_mask
, &prev_mask
);
2569 /* Always pull all events out of the kernel. We'll randomly select
2570 an event LWP out of all that have events, to prevent
2572 while (event_child
== NULL
)
2576 /* Always use -1 and WNOHANG, due to couple of a kernel/ptrace
2579 - If the thread group leader exits while other threads in the
2580 thread group still exist, waitpid(TGID, ...) hangs. That
2581 waitpid won't return an exit status until the other threads
2582 in the group are reaped.
2584 - When a non-leader thread execs, that thread just vanishes
2585 without reporting an exit (so we'd hang if we waited for it
2586 explicitly in that case). The exec event is reported to
2589 ret
= my_waitpid (-1, wstatp
, options
| WNOHANG
);
2592 debug_printf ("LWFE: waitpid(-1, ...) returned %d, %s\n",
2593 ret
, errno
? safe_strerror (errno
) : "ERRNO-OK");
2599 debug_printf ("LLW: waitpid %ld received %s\n",
2600 (long) ret
, status_to_str (*wstatp
).c_str ());
2603 /* Filter all events. IOW, leave all events pending. We'll
2604 randomly select an event LWP out of all that have events
2606 filter_event (ret
, *wstatp
);
2607 /* Retry until nothing comes out of waitpid. A single
2608 SIGCHLD can indicate more than one child stopped. */
2612 /* Now that we've pulled all events out of the kernel, resume
2613 LWPs that don't have an interesting event to report. */
2614 if (stopping_threads
== NOT_STOPPING_THREADS
)
2615 for_each_thread ([this] (thread_info
*thread
)
2617 resume_stopped_resumed_lwps (thread
);
2620 /* ... and find an LWP with a status to report to the core, if
2622 event_thread
= find_thread_in_random ([&] (thread_info
*thread
)
2624 return status_pending_p_callback (thread
, filter_ptid
);
2627 if (event_thread
!= NULL
)
2629 event_child
= get_thread_lwp (event_thread
);
2630 *wstatp
= event_child
->status_pending
;
2631 event_child
->status_pending_p
= 0;
2632 event_child
->status_pending
= 0;
2636 /* Check for zombie thread group leaders. Those can't be reaped
2637 until all other threads in the thread group are. */
2638 check_zombie_leaders ();
2640 auto not_stopped
= [&] (thread_info
*thread
)
2642 return not_stopped_callback (thread
, wait_ptid
);
2645 /* If there are no resumed children left in the set of LWPs we
2646 want to wait for, bail. We can't just block in
2647 waitpid/sigsuspend, because lwps might have been left stopped
2648 in trace-stop state, and we'd be stuck forever waiting for
2649 their status to change (which would only happen if we resumed
2650 them). Even if WNOHANG is set, this return code is preferred
2651 over 0 (below), as it is more detailed. */
2652 if (find_thread (not_stopped
) == NULL
)
2655 debug_printf ("LLW: exit (no unwaited-for LWP)\n");
2656 gdb_sigmask (SIG_SETMASK
, &prev_mask
, NULL
);
2660 /* No interesting event to report to the caller. */
2661 if ((options
& WNOHANG
))
2664 debug_printf ("WNOHANG set, no event found\n");
2666 gdb_sigmask (SIG_SETMASK
, &prev_mask
, NULL
);
2670 /* Block until we get an event reported with SIGCHLD. */
2672 debug_printf ("sigsuspend'ing\n");
2674 sigsuspend (&prev_mask
);
2675 gdb_sigmask (SIG_SETMASK
, &prev_mask
, NULL
);
2679 gdb_sigmask (SIG_SETMASK
, &prev_mask
, NULL
);
2681 current_thread
= event_thread
;
2683 return lwpid_of (event_thread
);
2687 linux_process_target::wait_for_event (ptid_t ptid
, int *wstatp
, int options
)
2689 return wait_for_event_filtered (ptid
, ptid
, wstatp
, options
);
2692 /* Select one LWP out of those that have events pending. */
2695 select_event_lwp (struct lwp_info
**orig_lp
)
2697 struct thread_info
*event_thread
= NULL
;
2699 /* In all-stop, give preference to the LWP that is being
2700 single-stepped. There will be at most one, and it's the LWP that
2701 the core is most interested in. If we didn't do this, then we'd
2702 have to handle pending step SIGTRAPs somehow in case the core
2703 later continues the previously-stepped thread, otherwise we'd
2704 report the pending SIGTRAP, and the core, not having stepped the
2705 thread, wouldn't understand what the trap was for, and therefore
2706 would report it to the user as a random signal. */
2709 event_thread
= find_thread ([] (thread_info
*thread
)
2711 lwp_info
*lp
= get_thread_lwp (thread
);
2713 return (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2714 && thread
->last_resume_kind
== resume_step
2715 && lp
->status_pending_p
);
2718 if (event_thread
!= NULL
)
2721 debug_printf ("SEL: Select single-step %s\n",
2722 target_pid_to_str (ptid_of (event_thread
)));
2725 if (event_thread
== NULL
)
2727 /* No single-stepping LWP. Select one at random, out of those
2728 which have had events. */
2730 event_thread
= find_thread_in_random ([&] (thread_info
*thread
)
2732 lwp_info
*lp
= get_thread_lwp (thread
);
2734 /* Only resumed LWPs that have an event pending. */
2735 return (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2736 && lp
->status_pending_p
);
2740 if (event_thread
!= NULL
)
2742 struct lwp_info
*event_lp
= get_thread_lwp (event_thread
);
2744 /* Switch the event LWP. */
2745 *orig_lp
= event_lp
;
2749 /* Decrement the suspend count of all LWPs, except EXCEPT, if non
2753 unsuspend_all_lwps (struct lwp_info
*except
)
2755 for_each_thread ([&] (thread_info
*thread
)
2757 lwp_info
*lwp
= get_thread_lwp (thread
);
2760 lwp_suspended_decr (lwp
);
2764 static bool lwp_running (thread_info
*thread
);
2766 /* Stabilize threads (move out of jump pads).
2768 If a thread is midway collecting a fast tracepoint, we need to
2769 finish the collection and move it out of the jump pad before
2770 reporting the signal.
2772 This avoids recursion while collecting (when a signal arrives
2773 midway, and the signal handler itself collects), which would trash
2774 the trace buffer. In case the user set a breakpoint in a signal
2775 handler, this avoids the backtrace showing the jump pad, etc..
2776 Most importantly, there are certain things we can't do safely if
2777 threads are stopped in a jump pad (or in its callee's). For
2780 - starting a new trace run. A thread still collecting the
2781 previous run, could trash the trace buffer when resumed. The trace
2782 buffer control structures would have been reset but the thread had
2783 no way to tell. The thread could even midway memcpy'ing to the
2784 buffer, which would mean that when resumed, it would clobber the
2785 trace buffer that had been set for a new run.
2787 - we can't rewrite/reuse the jump pads for new tracepoints
2788 safely. Say you do tstart while a thread is stopped midway while
2789 collecting. When the thread is later resumed, it finishes the
2790 collection, and returns to the jump pad, to execute the original
2791 instruction that was under the tracepoint jump at the time the
2792 older run had been started. If the jump pad had been rewritten
2793 since for something else in the new run, the thread would now
2794 execute the wrong / random instructions. */
2797 linux_process_target::stabilize_threads ()
2799 thread_info
*thread_stuck
= find_thread ([this] (thread_info
*thread
)
2801 return stuck_in_jump_pad (thread
);
2804 if (thread_stuck
!= NULL
)
2807 debug_printf ("can't stabilize, LWP %ld is stuck in jump pad\n",
2808 lwpid_of (thread_stuck
));
2812 thread_info
*saved_thread
= current_thread
;
2814 stabilizing_threads
= 1;
2817 for_each_thread ([this] (thread_info
*thread
)
2819 move_out_of_jump_pad (thread
);
2822 /* Loop until all are stopped out of the jump pads. */
2823 while (find_thread (lwp_running
) != NULL
)
2825 struct target_waitstatus ourstatus
;
2826 struct lwp_info
*lwp
;
2829 /* Note that we go through the full wait even loop. While
2830 moving threads out of jump pad, we need to be able to step
2831 over internal breakpoints and such. */
2832 wait_1 (minus_one_ptid
, &ourstatus
, 0);
2834 if (ourstatus
.kind
== TARGET_WAITKIND_STOPPED
)
2836 lwp
= get_thread_lwp (current_thread
);
2839 lwp_suspended_inc (lwp
);
2841 if (ourstatus
.value
.sig
!= GDB_SIGNAL_0
2842 || current_thread
->last_resume_kind
== resume_stop
)
2844 wstat
= W_STOPCODE (gdb_signal_to_host (ourstatus
.value
.sig
));
2845 enqueue_one_deferred_signal (lwp
, &wstat
);
2850 unsuspend_all_lwps (NULL
);
2852 stabilizing_threads
= 0;
2854 current_thread
= saved_thread
;
2858 thread_stuck
= find_thread ([this] (thread_info
*thread
)
2860 return stuck_in_jump_pad (thread
);
2863 if (thread_stuck
!= NULL
)
2864 debug_printf ("couldn't stabilize, LWP %ld got stuck in jump pad\n",
2865 lwpid_of (thread_stuck
));
2869 /* Convenience function that is called when the kernel reports an
2870 event that is not passed out to GDB. */
2873 ignore_event (struct target_waitstatus
*ourstatus
)
2875 /* If we got an event, there may still be others, as a single
2876 SIGCHLD can indicate more than one child stopped. This forces
2877 another target_wait call. */
2880 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2885 linux_process_target::filter_exit_event (lwp_info
*event_child
,
2886 target_waitstatus
*ourstatus
)
2888 client_state
&cs
= get_client_state ();
2889 struct thread_info
*thread
= get_lwp_thread (event_child
);
2890 ptid_t ptid
= ptid_of (thread
);
2892 if (!last_thread_of_process_p (pid_of (thread
)))
2894 if (cs
.report_thread_events
)
2895 ourstatus
->kind
= TARGET_WAITKIND_THREAD_EXITED
;
2897 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2899 delete_lwp (event_child
);
2904 /* Returns 1 if GDB is interested in any event_child syscalls. */
2907 gdb_catching_syscalls_p (struct lwp_info
*event_child
)
2909 struct thread_info
*thread
= get_lwp_thread (event_child
);
2910 struct process_info
*proc
= get_thread_process (thread
);
2912 return !proc
->syscalls_to_catch
.empty ();
2916 linux_process_target::gdb_catch_this_syscall (lwp_info
*event_child
)
2919 struct thread_info
*thread
= get_lwp_thread (event_child
);
2920 struct process_info
*proc
= get_thread_process (thread
);
2922 if (proc
->syscalls_to_catch
.empty ())
2925 if (proc
->syscalls_to_catch
[0] == ANY_SYSCALL
)
2928 get_syscall_trapinfo (event_child
, &sysno
);
2930 for (int iter
: proc
->syscalls_to_catch
)
2938 linux_process_target::wait_1 (ptid_t ptid
, target_waitstatus
*ourstatus
,
2939 target_wait_flags target_options
)
2941 client_state
&cs
= get_client_state ();
2943 struct lwp_info
*event_child
;
2946 int step_over_finished
;
2947 int bp_explains_trap
;
2948 int maybe_internal_trap
;
2957 debug_printf ("wait_1: [%s]\n", target_pid_to_str (ptid
));
2960 /* Translate generic target options into linux options. */
2962 if (target_options
& TARGET_WNOHANG
)
2965 bp_explains_trap
= 0;
2968 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2970 auto status_pending_p_any
= [&] (thread_info
*thread
)
2972 return status_pending_p_callback (thread
, minus_one_ptid
);
2975 auto not_stopped
= [&] (thread_info
*thread
)
2977 return not_stopped_callback (thread
, minus_one_ptid
);
2980 /* Find a resumed LWP, if any. */
2981 if (find_thread (status_pending_p_any
) != NULL
)
2983 else if (find_thread (not_stopped
) != NULL
)
2988 if (step_over_bkpt
== null_ptid
)
2989 pid
= wait_for_event (ptid
, &w
, options
);
2993 debug_printf ("step_over_bkpt set [%s], doing a blocking wait\n",
2994 target_pid_to_str (step_over_bkpt
));
2995 pid
= wait_for_event (step_over_bkpt
, &w
, options
& ~WNOHANG
);
2998 if (pid
== 0 || (pid
== -1 && !any_resumed
))
3000 gdb_assert (target_options
& TARGET_WNOHANG
);
3004 debug_printf ("wait_1 ret = null_ptid, "
3005 "TARGET_WAITKIND_IGNORE\n");
3009 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3016 debug_printf ("wait_1 ret = null_ptid, "
3017 "TARGET_WAITKIND_NO_RESUMED\n");
3021 ourstatus
->kind
= TARGET_WAITKIND_NO_RESUMED
;
3025 event_child
= get_thread_lwp (current_thread
);
3027 /* wait_for_event only returns an exit status for the last
3028 child of a process. Report it. */
3029 if (WIFEXITED (w
) || WIFSIGNALED (w
))
3033 ourstatus
->kind
= TARGET_WAITKIND_EXITED
;
3034 ourstatus
->value
.integer
= WEXITSTATUS (w
);
3038 debug_printf ("wait_1 ret = %s, exited with "
3040 target_pid_to_str (ptid_of (current_thread
)),
3047 ourstatus
->kind
= TARGET_WAITKIND_SIGNALLED
;
3048 ourstatus
->value
.sig
= gdb_signal_from_host (WTERMSIG (w
));
3052 debug_printf ("wait_1 ret = %s, terminated with "
3054 target_pid_to_str (ptid_of (current_thread
)),
3060 if (ourstatus
->kind
== TARGET_WAITKIND_EXITED
)
3061 return filter_exit_event (event_child
, ourstatus
);
3063 return ptid_of (current_thread
);
3066 /* If step-over executes a breakpoint instruction, in the case of a
3067 hardware single step it means a gdb/gdbserver breakpoint had been
3068 planted on top of a permanent breakpoint, in the case of a software
3069 single step it may just mean that gdbserver hit the reinsert breakpoint.
3070 The PC has been adjusted by save_stop_reason to point at
3071 the breakpoint address.
3072 So in the case of the hardware single step advance the PC manually
3073 past the breakpoint and in the case of software single step advance only
3074 if it's not the single_step_breakpoint we are hitting.
3075 This avoids that a program would keep trapping a permanent breakpoint
3077 if (step_over_bkpt
!= null_ptid
3078 && event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3079 && (event_child
->stepping
3080 || !single_step_breakpoint_inserted_here (event_child
->stop_pc
)))
3082 int increment_pc
= 0;
3083 int breakpoint_kind
= 0;
3084 CORE_ADDR stop_pc
= event_child
->stop_pc
;
3086 breakpoint_kind
= breakpoint_kind_from_current_state (&stop_pc
);
3087 sw_breakpoint_from_kind (breakpoint_kind
, &increment_pc
);
3091 debug_printf ("step-over for %s executed software breakpoint\n",
3092 target_pid_to_str (ptid_of (current_thread
)));
3095 if (increment_pc
!= 0)
3097 struct regcache
*regcache
3098 = get_thread_regcache (current_thread
, 1);
3100 event_child
->stop_pc
+= increment_pc
;
3101 low_set_pc (regcache
, event_child
->stop_pc
);
3103 if (!low_breakpoint_at (event_child
->stop_pc
))
3104 event_child
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3108 /* If this event was not handled before, and is not a SIGTRAP, we
3109 report it. SIGILL and SIGSEGV are also treated as traps in case
3110 a breakpoint is inserted at the current PC. If this target does
3111 not support internal breakpoints at all, we also report the
3112 SIGTRAP without further processing; it's of no concern to us. */
3114 = (low_supports_breakpoints ()
3115 && (WSTOPSIG (w
) == SIGTRAP
3116 || ((WSTOPSIG (w
) == SIGILL
3117 || WSTOPSIG (w
) == SIGSEGV
)
3118 && low_breakpoint_at (event_child
->stop_pc
))));
3120 if (maybe_internal_trap
)
3122 /* Handle anything that requires bookkeeping before deciding to
3123 report the event or continue waiting. */
3125 /* First check if we can explain the SIGTRAP with an internal
3126 breakpoint, or if we should possibly report the event to GDB.
3127 Do this before anything that may remove or insert a
3129 bp_explains_trap
= breakpoint_inserted_here (event_child
->stop_pc
);
3131 /* We have a SIGTRAP, possibly a step-over dance has just
3132 finished. If so, tweak the state machine accordingly,
3133 reinsert breakpoints and delete any single-step
3135 step_over_finished
= finish_step_over (event_child
);
3137 /* Now invoke the callbacks of any internal breakpoints there. */
3138 check_breakpoints (event_child
->stop_pc
);
3140 /* Handle tracepoint data collecting. This may overflow the
3141 trace buffer, and cause a tracing stop, removing
3143 trace_event
= handle_tracepoints (event_child
);
3145 if (bp_explains_trap
)
3148 debug_printf ("Hit a gdbserver breakpoint.\n");
3153 /* We have some other signal, possibly a step-over dance was in
3154 progress, and it should be cancelled too. */
3155 step_over_finished
= finish_step_over (event_child
);
3158 /* We have all the data we need. Either report the event to GDB, or
3159 resume threads and keep waiting for more. */
3161 /* If we're collecting a fast tracepoint, finish the collection and
3162 move out of the jump pad before delivering a signal. See
3163 linux_stabilize_threads. */
3166 && WSTOPSIG (w
) != SIGTRAP
3167 && supports_fast_tracepoints ()
3168 && agent_loaded_p ())
3171 debug_printf ("Got signal %d for LWP %ld. Check if we need "
3172 "to defer or adjust it.\n",
3173 WSTOPSIG (w
), lwpid_of (current_thread
));
3175 /* Allow debugging the jump pad itself. */
3176 if (current_thread
->last_resume_kind
!= resume_step
3177 && maybe_move_out_of_jump_pad (event_child
, &w
))
3179 enqueue_one_deferred_signal (event_child
, &w
);
3182 debug_printf ("Signal %d for LWP %ld deferred (in jump pad)\n",
3183 WSTOPSIG (w
), lwpid_of (current_thread
));
3185 resume_one_lwp (event_child
, 0, 0, NULL
);
3189 return ignore_event (ourstatus
);
3193 if (event_child
->collecting_fast_tracepoint
3194 != fast_tpoint_collect_result::not_collecting
)
3197 debug_printf ("LWP %ld was trying to move out of the jump pad (%d). "
3198 "Check if we're already there.\n",
3199 lwpid_of (current_thread
),
3200 (int) event_child
->collecting_fast_tracepoint
);
3204 event_child
->collecting_fast_tracepoint
3205 = linux_fast_tracepoint_collecting (event_child
, NULL
);
3207 if (event_child
->collecting_fast_tracepoint
3208 != fast_tpoint_collect_result::before_insn
)
3210 /* No longer need this breakpoint. */
3211 if (event_child
->exit_jump_pad_bkpt
!= NULL
)
3214 debug_printf ("No longer need exit-jump-pad bkpt; removing it."
3215 "stopping all threads momentarily.\n");
3217 /* Other running threads could hit this breakpoint.
3218 We don't handle moribund locations like GDB does,
3219 instead we always pause all threads when removing
3220 breakpoints, so that any step-over or
3221 decr_pc_after_break adjustment is always taken
3222 care of while the breakpoint is still
3224 stop_all_lwps (1, event_child
);
3226 delete_breakpoint (event_child
->exit_jump_pad_bkpt
);
3227 event_child
->exit_jump_pad_bkpt
= NULL
;
3229 unstop_all_lwps (1, event_child
);
3231 gdb_assert (event_child
->suspended
>= 0);
3235 if (event_child
->collecting_fast_tracepoint
3236 == fast_tpoint_collect_result::not_collecting
)
3239 debug_printf ("fast tracepoint finished "
3240 "collecting successfully.\n");
3242 /* We may have a deferred signal to report. */
3243 if (dequeue_one_deferred_signal (event_child
, &w
))
3246 debug_printf ("dequeued one signal.\n");
3251 debug_printf ("no deferred signals.\n");
3253 if (stabilizing_threads
)
3255 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
3256 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
3260 debug_printf ("wait_1 ret = %s, stopped "
3261 "while stabilizing threads\n",
3262 target_pid_to_str (ptid_of (current_thread
)));
3266 return ptid_of (current_thread
);
3272 /* Check whether GDB would be interested in this event. */
3274 /* Check if GDB is interested in this syscall. */
3276 && WSTOPSIG (w
) == SYSCALL_SIGTRAP
3277 && !gdb_catch_this_syscall (event_child
))
3281 debug_printf ("Ignored syscall for LWP %ld.\n",
3282 lwpid_of (current_thread
));
3285 resume_one_lwp (event_child
, event_child
->stepping
, 0, NULL
);
3289 return ignore_event (ourstatus
);
3292 /* If GDB is not interested in this signal, don't stop other
3293 threads, and don't report it to GDB. Just resume the inferior
3294 right away. We do this for threading-related signals as well as
3295 any that GDB specifically requested we ignore. But never ignore
3296 SIGSTOP if we sent it ourselves, and do not ignore signals when
3297 stepping - they may require special handling to skip the signal
3298 handler. Also never ignore signals that could be caused by a
3301 && current_thread
->last_resume_kind
!= resume_step
3303 #if defined (USE_THREAD_DB) && !defined (__ANDROID__)
3304 (current_process ()->priv
->thread_db
!= NULL
3305 && (WSTOPSIG (w
) == __SIGRTMIN
3306 || WSTOPSIG (w
) == __SIGRTMIN
+ 1))
3309 (cs
.pass_signals
[gdb_signal_from_host (WSTOPSIG (w
))]
3310 && !(WSTOPSIG (w
) == SIGSTOP
3311 && current_thread
->last_resume_kind
== resume_stop
)
3312 && !linux_wstatus_maybe_breakpoint (w
))))
3314 siginfo_t info
, *info_p
;
3317 debug_printf ("Ignored signal %d for LWP %ld.\n",
3318 WSTOPSIG (w
), lwpid_of (current_thread
));
3320 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
3321 (PTRACE_TYPE_ARG3
) 0, &info
) == 0)
3326 if (step_over_finished
)
3328 /* We cancelled this thread's step-over above. We still
3329 need to unsuspend all other LWPs, and set them back
3330 running again while the signal handler runs. */
3331 unsuspend_all_lwps (event_child
);
3333 /* Enqueue the pending signal info so that proceed_all_lwps
3335 enqueue_pending_signal (event_child
, WSTOPSIG (w
), info_p
);
3337 proceed_all_lwps ();
3341 resume_one_lwp (event_child
, event_child
->stepping
,
3342 WSTOPSIG (w
), info_p
);
3348 return ignore_event (ourstatus
);
3351 /* Note that all addresses are always "out of the step range" when
3352 there's no range to begin with. */
3353 in_step_range
= lwp_in_step_range (event_child
);
3355 /* If GDB wanted this thread to single step, and the thread is out
3356 of the step range, we always want to report the SIGTRAP, and let
3357 GDB handle it. Watchpoints should always be reported. So should
3358 signals we can't explain. A SIGTRAP we can't explain could be a
3359 GDB breakpoint --- we may or not support Z0 breakpoints. If we
3360 do, we're be able to handle GDB breakpoints on top of internal
3361 breakpoints, by handling the internal breakpoint and still
3362 reporting the event to GDB. If we don't, we're out of luck, GDB
3363 won't see the breakpoint hit. If we see a single-step event but
3364 the thread should be continuing, don't pass the trap to gdb.
3365 That indicates that we had previously finished a single-step but
3366 left the single-step pending -- see
3367 complete_ongoing_step_over. */
3368 report_to_gdb
= (!maybe_internal_trap
3369 || (current_thread
->last_resume_kind
== resume_step
3371 || event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
3373 && !bp_explains_trap
3375 && !step_over_finished
3376 && !(current_thread
->last_resume_kind
== resume_continue
3377 && event_child
->stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
))
3378 || (gdb_breakpoint_here (event_child
->stop_pc
)
3379 && gdb_condition_true_at_breakpoint (event_child
->stop_pc
)
3380 && gdb_no_commands_at_breakpoint (event_child
->stop_pc
))
3381 || event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
);
3383 run_breakpoint_commands (event_child
->stop_pc
);
3385 /* We found no reason GDB would want us to stop. We either hit one
3386 of our own breakpoints, or finished an internal step GDB
3387 shouldn't know about. */
3392 if (bp_explains_trap
)
3393 debug_printf ("Hit a gdbserver breakpoint.\n");
3394 if (step_over_finished
)
3395 debug_printf ("Step-over finished.\n");
3397 debug_printf ("Tracepoint event.\n");
3398 if (lwp_in_step_range (event_child
))
3399 debug_printf ("Range stepping pc 0x%s [0x%s, 0x%s).\n",
3400 paddress (event_child
->stop_pc
),
3401 paddress (event_child
->step_range_start
),
3402 paddress (event_child
->step_range_end
));
3405 /* We're not reporting this breakpoint to GDB, so apply the
3406 decr_pc_after_break adjustment to the inferior's regcache
3409 if (low_supports_breakpoints ())
3411 struct regcache
*regcache
3412 = get_thread_regcache (current_thread
, 1);
3413 low_set_pc (regcache
, event_child
->stop_pc
);
3416 if (step_over_finished
)
3418 /* If we have finished stepping over a breakpoint, we've
3419 stopped and suspended all LWPs momentarily except the
3420 stepping one. This is where we resume them all again.
3421 We're going to keep waiting, so use proceed, which
3422 handles stepping over the next breakpoint. */
3423 unsuspend_all_lwps (event_child
);
3427 /* Remove the single-step breakpoints if any. Note that
3428 there isn't single-step breakpoint if we finished stepping
3430 if (supports_software_single_step ()
3431 && has_single_step_breakpoints (current_thread
))
3433 stop_all_lwps (0, event_child
);
3434 delete_single_step_breakpoints (current_thread
);
3435 unstop_all_lwps (0, event_child
);
3440 debug_printf ("proceeding all threads.\n");
3441 proceed_all_lwps ();
3446 return ignore_event (ourstatus
);
3451 if (event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
3454 = target_waitstatus_to_string (&event_child
->waitstatus
);
3456 debug_printf ("LWP %ld: extended event with waitstatus %s\n",
3457 lwpid_of (get_lwp_thread (event_child
)), str
.c_str ());
3459 if (current_thread
->last_resume_kind
== resume_step
)
3461 if (event_child
->step_range_start
== event_child
->step_range_end
)
3462 debug_printf ("GDB wanted to single-step, reporting event.\n");
3463 else if (!lwp_in_step_range (event_child
))
3464 debug_printf ("Out of step range, reporting event.\n");
3466 if (event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
)
3467 debug_printf ("Stopped by watchpoint.\n");
3468 else if (gdb_breakpoint_here (event_child
->stop_pc
))
3469 debug_printf ("Stopped by GDB breakpoint.\n");
3471 debug_printf ("Hit a non-gdbserver trap event.\n");
3474 /* Alright, we're going to report a stop. */
3476 /* Remove single-step breakpoints. */
3477 if (supports_software_single_step ())
3479 /* Remove single-step breakpoints or not. It it is true, stop all
3480 lwps, so that other threads won't hit the breakpoint in the
3482 int remove_single_step_breakpoints_p
= 0;
3486 remove_single_step_breakpoints_p
3487 = has_single_step_breakpoints (current_thread
);
3491 /* In all-stop, a stop reply cancels all previous resume
3492 requests. Delete all single-step breakpoints. */
3494 find_thread ([&] (thread_info
*thread
) {
3495 if (has_single_step_breakpoints (thread
))
3497 remove_single_step_breakpoints_p
= 1;
3505 if (remove_single_step_breakpoints_p
)
3507 /* If we remove single-step breakpoints from memory, stop all lwps,
3508 so that other threads won't hit the breakpoint in the staled
3510 stop_all_lwps (0, event_child
);
3514 gdb_assert (has_single_step_breakpoints (current_thread
));
3515 delete_single_step_breakpoints (current_thread
);
3519 for_each_thread ([] (thread_info
*thread
){
3520 if (has_single_step_breakpoints (thread
))
3521 delete_single_step_breakpoints (thread
);
3525 unstop_all_lwps (0, event_child
);
3529 if (!stabilizing_threads
)
3531 /* In all-stop, stop all threads. */
3533 stop_all_lwps (0, NULL
);
3535 if (step_over_finished
)
3539 /* If we were doing a step-over, all other threads but
3540 the stepping one had been paused in start_step_over,
3541 with their suspend counts incremented. We don't want
3542 to do a full unstop/unpause, because we're in
3543 all-stop mode (so we want threads stopped), but we
3544 still need to unsuspend the other threads, to
3545 decrement their `suspended' count back. */
3546 unsuspend_all_lwps (event_child
);
3550 /* If we just finished a step-over, then all threads had
3551 been momentarily paused. In all-stop, that's fine,
3552 we want threads stopped by now anyway. In non-stop,
3553 we need to re-resume threads that GDB wanted to be
3555 unstop_all_lwps (1, event_child
);
3559 /* If we're not waiting for a specific LWP, choose an event LWP
3560 from among those that have had events. Giving equal priority
3561 to all LWPs that have had events helps prevent
3563 if (ptid
== minus_one_ptid
)
3565 event_child
->status_pending_p
= 1;
3566 event_child
->status_pending
= w
;
3568 select_event_lwp (&event_child
);
3570 /* current_thread and event_child must stay in sync. */
3571 current_thread
= get_lwp_thread (event_child
);
3573 event_child
->status_pending_p
= 0;
3574 w
= event_child
->status_pending
;
3578 /* Stabilize threads (move out of jump pads). */
3580 target_stabilize_threads ();
3584 /* If we just finished a step-over, then all threads had been
3585 momentarily paused. In all-stop, that's fine, we want
3586 threads stopped by now anyway. In non-stop, we need to
3587 re-resume threads that GDB wanted to be running. */
3588 if (step_over_finished
)
3589 unstop_all_lwps (1, event_child
);
3592 if (event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
3594 /* If the reported event is an exit, fork, vfork or exec, let
3597 /* Break the unreported fork relationship chain. */
3598 if (event_child
->waitstatus
.kind
== TARGET_WAITKIND_FORKED
3599 || event_child
->waitstatus
.kind
== TARGET_WAITKIND_VFORKED
)
3601 event_child
->fork_relative
->fork_relative
= NULL
;
3602 event_child
->fork_relative
= NULL
;
3605 *ourstatus
= event_child
->waitstatus
;
3606 /* Clear the event lwp's waitstatus since we handled it already. */
3607 event_child
->waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
3610 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
3612 /* Now that we've selected our final event LWP, un-adjust its PC if
3613 it was a software breakpoint, and the client doesn't know we can
3614 adjust the breakpoint ourselves. */
3615 if (event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3616 && !cs
.swbreak_feature
)
3618 int decr_pc
= low_decr_pc_after_break ();
3622 struct regcache
*regcache
3623 = get_thread_regcache (current_thread
, 1);
3624 low_set_pc (regcache
, event_child
->stop_pc
+ decr_pc
);
3628 if (WSTOPSIG (w
) == SYSCALL_SIGTRAP
)
3630 get_syscall_trapinfo (event_child
,
3631 &ourstatus
->value
.syscall_number
);
3632 ourstatus
->kind
= event_child
->syscall_state
;
3634 else if (current_thread
->last_resume_kind
== resume_stop
3635 && WSTOPSIG (w
) == SIGSTOP
)
3637 /* A thread that has been requested to stop by GDB with vCont;t,
3638 and it stopped cleanly, so report as SIG0. The use of
3639 SIGSTOP is an implementation detail. */
3640 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
3642 else if (current_thread
->last_resume_kind
== resume_stop
3643 && WSTOPSIG (w
) != SIGSTOP
)
3645 /* A thread that has been requested to stop by GDB with vCont;t,
3646 but, it stopped for other reasons. */
3647 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
3649 else if (ourstatus
->kind
== TARGET_WAITKIND_STOPPED
)
3651 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
3654 gdb_assert (step_over_bkpt
== null_ptid
);
3658 debug_printf ("wait_1 ret = %s, %d, %d\n",
3659 target_pid_to_str (ptid_of (current_thread
)),
3660 ourstatus
->kind
, ourstatus
->value
.sig
);
3664 if (ourstatus
->kind
== TARGET_WAITKIND_EXITED
)
3665 return filter_exit_event (event_child
, ourstatus
);
3667 return ptid_of (current_thread
);
3670 /* Get rid of any pending event in the pipe. */
3672 async_file_flush (void)
3678 ret
= read (linux_event_pipe
[0], &buf
, 1);
3679 while (ret
>= 0 || (ret
== -1 && errno
== EINTR
));
3682 /* Put something in the pipe, so the event loop wakes up. */
3684 async_file_mark (void)
3688 async_file_flush ();
3691 ret
= write (linux_event_pipe
[1], "+", 1);
3692 while (ret
== 0 || (ret
== -1 && errno
== EINTR
));
3694 /* Ignore EAGAIN. If the pipe is full, the event loop will already
3695 be awakened anyway. */
3699 linux_process_target::wait (ptid_t ptid
,
3700 target_waitstatus
*ourstatus
,
3701 target_wait_flags target_options
)
3705 /* Flush the async file first. */
3706 if (target_is_async_p ())
3707 async_file_flush ();
3711 event_ptid
= wait_1 (ptid
, ourstatus
, target_options
);
3713 while ((target_options
& TARGET_WNOHANG
) == 0
3714 && event_ptid
== null_ptid
3715 && ourstatus
->kind
== TARGET_WAITKIND_IGNORE
);
3717 /* If at least one stop was reported, there may be more. A single
3718 SIGCHLD can signal more than one child stop. */
3719 if (target_is_async_p ()
3720 && (target_options
& TARGET_WNOHANG
) != 0
3721 && event_ptid
!= null_ptid
)
3727 /* Send a signal to an LWP. */
3730 kill_lwp (unsigned long lwpid
, int signo
)
3735 ret
= syscall (__NR_tkill
, lwpid
, signo
);
3736 if (errno
== ENOSYS
)
3738 /* If tkill fails, then we are not using nptl threads, a
3739 configuration we no longer support. */
3740 perror_with_name (("tkill"));
3746 linux_stop_lwp (struct lwp_info
*lwp
)
3752 send_sigstop (struct lwp_info
*lwp
)
3756 pid
= lwpid_of (get_lwp_thread (lwp
));
3758 /* If we already have a pending stop signal for this process, don't
3760 if (lwp
->stop_expected
)
3763 debug_printf ("Have pending sigstop for lwp %d\n", pid
);
3769 debug_printf ("Sending sigstop to lwp %d\n", pid
);
3771 lwp
->stop_expected
= 1;
3772 kill_lwp (pid
, SIGSTOP
);
3776 send_sigstop (thread_info
*thread
, lwp_info
*except
)
3778 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3780 /* Ignore EXCEPT. */
3790 /* Increment the suspend count of an LWP, and stop it, if not stopped
3793 suspend_and_send_sigstop (thread_info
*thread
, lwp_info
*except
)
3795 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3797 /* Ignore EXCEPT. */
3801 lwp_suspended_inc (lwp
);
3803 send_sigstop (thread
, except
);
3807 mark_lwp_dead (struct lwp_info
*lwp
, int wstat
)
3809 /* Store the exit status for later. */
3810 lwp
->status_pending_p
= 1;
3811 lwp
->status_pending
= wstat
;
3813 /* Store in waitstatus as well, as there's nothing else to process
3815 if (WIFEXITED (wstat
))
3817 lwp
->waitstatus
.kind
= TARGET_WAITKIND_EXITED
;
3818 lwp
->waitstatus
.value
.integer
= WEXITSTATUS (wstat
);
3820 else if (WIFSIGNALED (wstat
))
3822 lwp
->waitstatus
.kind
= TARGET_WAITKIND_SIGNALLED
;
3823 lwp
->waitstatus
.value
.sig
= gdb_signal_from_host (WTERMSIG (wstat
));
3826 /* Prevent trying to stop it. */
3829 /* No further stops are expected from a dead lwp. */
3830 lwp
->stop_expected
= 0;
3833 /* Return true if LWP has exited already, and has a pending exit event
3834 to report to GDB. */
3837 lwp_is_marked_dead (struct lwp_info
*lwp
)
3839 return (lwp
->status_pending_p
3840 && (WIFEXITED (lwp
->status_pending
)
3841 || WIFSIGNALED (lwp
->status_pending
)));
3845 linux_process_target::wait_for_sigstop ()
3847 struct thread_info
*saved_thread
;
3852 saved_thread
= current_thread
;
3853 if (saved_thread
!= NULL
)
3854 saved_tid
= saved_thread
->id
;
3856 saved_tid
= null_ptid
; /* avoid bogus unused warning */
3859 debug_printf ("wait_for_sigstop: pulling events\n");
3861 /* Passing NULL_PTID as filter indicates we want all events to be
3862 left pending. Eventually this returns when there are no
3863 unwaited-for children left. */
3864 ret
= wait_for_event_filtered (minus_one_ptid
, null_ptid
, &wstat
, __WALL
);
3865 gdb_assert (ret
== -1);
3867 if (saved_thread
== NULL
|| mythread_alive (saved_tid
))
3868 current_thread
= saved_thread
;
3872 debug_printf ("Previously current thread died.\n");
3874 /* We can't change the current inferior behind GDB's back,
3875 otherwise, a subsequent command may apply to the wrong
3877 current_thread
= NULL
;
3882 linux_process_target::stuck_in_jump_pad (thread_info
*thread
)
3884 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3886 if (lwp
->suspended
!= 0)
3888 internal_error (__FILE__
, __LINE__
,
3889 "LWP %ld is suspended, suspended=%d\n",
3890 lwpid_of (thread
), lwp
->suspended
);
3892 gdb_assert (lwp
->stopped
);
3894 /* Allow debugging the jump pad, gdb_collect, etc.. */
3895 return (supports_fast_tracepoints ()
3896 && agent_loaded_p ()
3897 && (gdb_breakpoint_here (lwp
->stop_pc
)
3898 || lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
3899 || thread
->last_resume_kind
== resume_step
)
3900 && (linux_fast_tracepoint_collecting (lwp
, NULL
)
3901 != fast_tpoint_collect_result::not_collecting
));
3905 linux_process_target::move_out_of_jump_pad (thread_info
*thread
)
3907 struct thread_info
*saved_thread
;
3908 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3911 if (lwp
->suspended
!= 0)
3913 internal_error (__FILE__
, __LINE__
,
3914 "LWP %ld is suspended, suspended=%d\n",
3915 lwpid_of (thread
), lwp
->suspended
);
3917 gdb_assert (lwp
->stopped
);
3919 /* For gdb_breakpoint_here. */
3920 saved_thread
= current_thread
;
3921 current_thread
= thread
;
3923 wstat
= lwp
->status_pending_p
? &lwp
->status_pending
: NULL
;
3925 /* Allow debugging the jump pad, gdb_collect, etc. */
3926 if (!gdb_breakpoint_here (lwp
->stop_pc
)
3927 && lwp
->stop_reason
!= TARGET_STOPPED_BY_WATCHPOINT
3928 && thread
->last_resume_kind
!= resume_step
3929 && maybe_move_out_of_jump_pad (lwp
, wstat
))
3932 debug_printf ("LWP %ld needs stabilizing (in jump pad)\n",
3937 lwp
->status_pending_p
= 0;
3938 enqueue_one_deferred_signal (lwp
, wstat
);
3941 debug_printf ("Signal %d for LWP %ld deferred "
3943 WSTOPSIG (*wstat
), lwpid_of (thread
));
3946 resume_one_lwp (lwp
, 0, 0, NULL
);
3949 lwp_suspended_inc (lwp
);
3951 current_thread
= saved_thread
;
3955 lwp_running (thread_info
*thread
)
3957 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3959 if (lwp_is_marked_dead (lwp
))
3962 return !lwp
->stopped
;
3966 linux_process_target::stop_all_lwps (int suspend
, lwp_info
*except
)
3968 /* Should not be called recursively. */
3969 gdb_assert (stopping_threads
== NOT_STOPPING_THREADS
);
3974 debug_printf ("stop_all_lwps (%s, except=%s)\n",
3975 suspend
? "stop-and-suspend" : "stop",
3977 ? target_pid_to_str (ptid_of (get_lwp_thread (except
)))
3981 stopping_threads
= (suspend
3982 ? STOPPING_AND_SUSPENDING_THREADS
3983 : STOPPING_THREADS
);
3986 for_each_thread ([&] (thread_info
*thread
)
3988 suspend_and_send_sigstop (thread
, except
);
3991 for_each_thread ([&] (thread_info
*thread
)
3993 send_sigstop (thread
, except
);
3996 wait_for_sigstop ();
3997 stopping_threads
= NOT_STOPPING_THREADS
;
4001 debug_printf ("stop_all_lwps done, setting stopping_threads "
4002 "back to !stopping\n");
4007 /* Enqueue one signal in the chain of signals which need to be
4008 delivered to this process on next resume. */
4011 enqueue_pending_signal (struct lwp_info
*lwp
, int signal
, siginfo_t
*info
)
4013 lwp
->pending_signals
.emplace_back (signal
);
4014 if (info
== nullptr)
4015 memset (&lwp
->pending_signals
.back ().info
, 0, sizeof (siginfo_t
));
4017 lwp
->pending_signals
.back ().info
= *info
;
4021 linux_process_target::install_software_single_step_breakpoints (lwp_info
*lwp
)
4023 struct thread_info
*thread
= get_lwp_thread (lwp
);
4024 struct regcache
*regcache
= get_thread_regcache (thread
, 1);
4026 scoped_restore save_current_thread
= make_scoped_restore (¤t_thread
);
4028 current_thread
= thread
;
4029 std::vector
<CORE_ADDR
> next_pcs
= low_get_next_pcs (regcache
);
4031 for (CORE_ADDR pc
: next_pcs
)
4032 set_single_step_breakpoint (pc
, current_ptid
);
4036 linux_process_target::single_step (lwp_info
* lwp
)
4040 if (supports_hardware_single_step ())
4044 else if (supports_software_single_step ())
4046 install_software_single_step_breakpoints (lwp
);
4052 debug_printf ("stepping is not implemented on this target");
4058 /* The signal can be delivered to the inferior if we are not trying to
4059 finish a fast tracepoint collect. Since signal can be delivered in
4060 the step-over, the program may go to signal handler and trap again
4061 after return from the signal handler. We can live with the spurious
4065 lwp_signal_can_be_delivered (struct lwp_info
*lwp
)
4067 return (lwp
->collecting_fast_tracepoint
4068 == fast_tpoint_collect_result::not_collecting
);
4072 linux_process_target::resume_one_lwp_throw (lwp_info
*lwp
, int step
,
4073 int signal
, siginfo_t
*info
)
4075 struct thread_info
*thread
= get_lwp_thread (lwp
);
4076 struct thread_info
*saved_thread
;
4078 struct process_info
*proc
= get_thread_process (thread
);
4080 /* Note that target description may not be initialised
4081 (proc->tdesc == NULL) at this point because the program hasn't
4082 stopped at the first instruction yet. It means GDBserver skips
4083 the extra traps from the wrapper program (see option --wrapper).
4084 Code in this function that requires register access should be
4085 guarded by proc->tdesc == NULL or something else. */
4087 if (lwp
->stopped
== 0)
4090 gdb_assert (lwp
->waitstatus
.kind
== TARGET_WAITKIND_IGNORE
);
4092 fast_tpoint_collect_result fast_tp_collecting
4093 = lwp
->collecting_fast_tracepoint
;
4095 gdb_assert (!stabilizing_threads
4096 || (fast_tp_collecting
4097 != fast_tpoint_collect_result::not_collecting
));
4099 /* Cancel actions that rely on GDB not changing the PC (e.g., the
4100 user used the "jump" command, or "set $pc = foo"). */
4101 if (thread
->while_stepping
!= NULL
&& lwp
->stop_pc
!= get_pc (lwp
))
4103 /* Collecting 'while-stepping' actions doesn't make sense
4105 release_while_stepping_state_list (thread
);
4108 /* If we have pending signals or status, and a new signal, enqueue the
4109 signal. Also enqueue the signal if it can't be delivered to the
4110 inferior right now. */
4112 && (lwp
->status_pending_p
4113 || !lwp
->pending_signals
.empty ()
4114 || !lwp_signal_can_be_delivered (lwp
)))
4116 enqueue_pending_signal (lwp
, signal
, info
);
4118 /* Postpone any pending signal. It was enqueued above. */
4122 if (lwp
->status_pending_p
)
4125 debug_printf ("Not resuming lwp %ld (%s, stop %s);"
4126 " has pending status\n",
4127 lwpid_of (thread
), step
? "step" : "continue",
4128 lwp
->stop_expected
? "expected" : "not expected");
4132 saved_thread
= current_thread
;
4133 current_thread
= thread
;
4135 /* This bit needs some thinking about. If we get a signal that
4136 we must report while a single-step reinsert is still pending,
4137 we often end up resuming the thread. It might be better to
4138 (ew) allow a stack of pending events; then we could be sure that
4139 the reinsert happened right away and not lose any signals.
4141 Making this stack would also shrink the window in which breakpoints are
4142 uninserted (see comment in linux_wait_for_lwp) but not enough for
4143 complete correctness, so it won't solve that problem. It may be
4144 worthwhile just to solve this one, however. */
4145 if (lwp
->bp_reinsert
!= 0)
4148 debug_printf (" pending reinsert at 0x%s\n",
4149 paddress (lwp
->bp_reinsert
));
4151 if (supports_hardware_single_step ())
4153 if (fast_tp_collecting
== fast_tpoint_collect_result::not_collecting
)
4156 warning ("BAD - reinserting but not stepping.");
4158 warning ("BAD - reinserting and suspended(%d).",
4163 step
= maybe_hw_step (thread
);
4166 if (fast_tp_collecting
== fast_tpoint_collect_result::before_insn
)
4169 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
4170 " (exit-jump-pad-bkpt)\n",
4173 else if (fast_tp_collecting
== fast_tpoint_collect_result::at_insn
)
4176 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
4177 " single-stepping\n",
4180 if (supports_hardware_single_step ())
4184 internal_error (__FILE__
, __LINE__
,
4185 "moving out of jump pad single-stepping"
4186 " not implemented on this target");
4190 /* If we have while-stepping actions in this thread set it stepping.
4191 If we have a signal to deliver, it may or may not be set to
4192 SIG_IGN, we don't know. Assume so, and allow collecting
4193 while-stepping into a signal handler. A possible smart thing to
4194 do would be to set an internal breakpoint at the signal return
4195 address, continue, and carry on catching this while-stepping
4196 action only when that breakpoint is hit. A future
4198 if (thread
->while_stepping
!= NULL
)
4201 debug_printf ("lwp %ld has a while-stepping action -> forcing step.\n",
4204 step
= single_step (lwp
);
4207 if (proc
->tdesc
!= NULL
&& low_supports_breakpoints ())
4209 struct regcache
*regcache
= get_thread_regcache (current_thread
, 1);
4211 lwp
->stop_pc
= low_get_pc (regcache
);
4215 debug_printf (" %s from pc 0x%lx\n", step
? "step" : "continue",
4216 (long) lwp
->stop_pc
);
4220 /* If we have pending signals, consume one if it can be delivered to
4222 if (!lwp
->pending_signals
.empty () && lwp_signal_can_be_delivered (lwp
))
4224 const pending_signal
&p_sig
= lwp
->pending_signals
.front ();
4226 signal
= p_sig
.signal
;
4227 if (p_sig
.info
.si_signo
!= 0)
4228 ptrace (PTRACE_SETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
4231 lwp
->pending_signals
.pop_front ();
4235 debug_printf ("Resuming lwp %ld (%s, signal %d, stop %s)\n",
4236 lwpid_of (thread
), step
? "step" : "continue", signal
,
4237 lwp
->stop_expected
? "expected" : "not expected");
4239 low_prepare_to_resume (lwp
);
4241 regcache_invalidate_thread (thread
);
4243 lwp
->stepping
= step
;
4245 ptrace_request
= PTRACE_SINGLESTEP
;
4246 else if (gdb_catching_syscalls_p (lwp
))
4247 ptrace_request
= PTRACE_SYSCALL
;
4249 ptrace_request
= PTRACE_CONT
;
4250 ptrace (ptrace_request
,
4252 (PTRACE_TYPE_ARG3
) 0,
4253 /* Coerce to a uintptr_t first to avoid potential gcc warning
4254 of coercing an 8 byte integer to a 4 byte pointer. */
4255 (PTRACE_TYPE_ARG4
) (uintptr_t) signal
);
4257 current_thread
= saved_thread
;
4259 perror_with_name ("resuming thread");
4261 /* Successfully resumed. Clear state that no longer makes sense,
4262 and mark the LWP as running. Must not do this before resuming
4263 otherwise if that fails other code will be confused. E.g., we'd
4264 later try to stop the LWP and hang forever waiting for a stop
4265 status. Note that we must not throw after this is cleared,
4266 otherwise handle_zombie_lwp_error would get confused. */
4268 lwp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
4272 linux_process_target::low_prepare_to_resume (lwp_info
*lwp
)
4277 /* Called when we try to resume a stopped LWP and that errors out. If
4278 the LWP is no longer in ptrace-stopped state (meaning it's zombie,
4279 or about to become), discard the error, clear any pending status
4280 the LWP may have, and return true (we'll collect the exit status
4281 soon enough). Otherwise, return false. */
4284 check_ptrace_stopped_lwp_gone (struct lwp_info
*lp
)
4286 struct thread_info
*thread
= get_lwp_thread (lp
);
4288 /* If we get an error after resuming the LWP successfully, we'd
4289 confuse !T state for the LWP being gone. */
4290 gdb_assert (lp
->stopped
);
4292 /* We can't just check whether the LWP is in 'Z (Zombie)' state,
4293 because even if ptrace failed with ESRCH, the tracee may be "not
4294 yet fully dead", but already refusing ptrace requests. In that
4295 case the tracee has 'R (Running)' state for a little bit
4296 (observed in Linux 3.18). See also the note on ESRCH in the
4297 ptrace(2) man page. Instead, check whether the LWP has any state
4298 other than ptrace-stopped. */
4300 /* Don't assume anything if /proc/PID/status can't be read. */
4301 if (linux_proc_pid_is_trace_stopped_nowarn (lwpid_of (thread
)) == 0)
4303 lp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
4304 lp
->status_pending_p
= 0;
4311 linux_process_target::resume_one_lwp (lwp_info
*lwp
, int step
, int signal
,
4316 resume_one_lwp_throw (lwp
, step
, signal
, info
);
4318 catch (const gdb_exception_error
&ex
)
4320 if (!check_ptrace_stopped_lwp_gone (lwp
))
4325 /* This function is called once per thread via for_each_thread.
4326 We look up which resume request applies to THREAD and mark it with a
4327 pointer to the appropriate resume request.
4329 This algorithm is O(threads * resume elements), but resume elements
4330 is small (and will remain small at least until GDB supports thread
4334 linux_set_resume_request (thread_info
*thread
, thread_resume
*resume
, size_t n
)
4336 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4338 for (int ndx
= 0; ndx
< n
; ndx
++)
4340 ptid_t ptid
= resume
[ndx
].thread
;
4341 if (ptid
== minus_one_ptid
4342 || ptid
== thread
->id
4343 /* Handle both 'pPID' and 'pPID.-1' as meaning 'all threads
4345 || (ptid
.pid () == pid_of (thread
)
4347 || ptid
.lwp () == -1)))
4349 if (resume
[ndx
].kind
== resume_stop
4350 && thread
->last_resume_kind
== resume_stop
)
4353 debug_printf ("already %s LWP %ld at GDB's request\n",
4354 (thread
->last_status
.kind
4355 == TARGET_WAITKIND_STOPPED
)
4363 /* Ignore (wildcard) resume requests for already-resumed
4365 if (resume
[ndx
].kind
!= resume_stop
4366 && thread
->last_resume_kind
!= resume_stop
)
4369 debug_printf ("already %s LWP %ld at GDB's request\n",
4370 (thread
->last_resume_kind
4378 /* Don't let wildcard resumes resume fork children that GDB
4379 does not yet know are new fork children. */
4380 if (lwp
->fork_relative
!= NULL
)
4382 struct lwp_info
*rel
= lwp
->fork_relative
;
4384 if (rel
->status_pending_p
4385 && (rel
->waitstatus
.kind
== TARGET_WAITKIND_FORKED
4386 || rel
->waitstatus
.kind
== TARGET_WAITKIND_VFORKED
))
4389 debug_printf ("not resuming LWP %ld: has queued stop reply\n",
4395 /* If the thread has a pending event that has already been
4396 reported to GDBserver core, but GDB has not pulled the
4397 event out of the vStopped queue yet, likewise, ignore the
4398 (wildcard) resume request. */
4399 if (in_queued_stop_replies (thread
->id
))
4402 debug_printf ("not resuming LWP %ld: has queued stop reply\n",
4407 lwp
->resume
= &resume
[ndx
];
4408 thread
->last_resume_kind
= lwp
->resume
->kind
;
4410 lwp
->step_range_start
= lwp
->resume
->step_range_start
;
4411 lwp
->step_range_end
= lwp
->resume
->step_range_end
;
4413 /* If we had a deferred signal to report, dequeue one now.
4414 This can happen if LWP gets more than one signal while
4415 trying to get out of a jump pad. */
4417 && !lwp
->status_pending_p
4418 && dequeue_one_deferred_signal (lwp
, &lwp
->status_pending
))
4420 lwp
->status_pending_p
= 1;
4423 debug_printf ("Dequeueing deferred signal %d for LWP %ld, "
4424 "leaving status pending.\n",
4425 WSTOPSIG (lwp
->status_pending
),
4433 /* No resume action for this thread. */
4438 linux_process_target::resume_status_pending (thread_info
*thread
)
4440 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4442 /* LWPs which will not be resumed are not interesting, because
4443 we might not wait for them next time through linux_wait. */
4444 if (lwp
->resume
== NULL
)
4447 return thread_still_has_status_pending (thread
);
4451 linux_process_target::thread_needs_step_over (thread_info
*thread
)
4453 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4454 struct thread_info
*saved_thread
;
4456 struct process_info
*proc
= get_thread_process (thread
);
4458 /* GDBserver is skipping the extra traps from the wrapper program,
4459 don't have to do step over. */
4460 if (proc
->tdesc
== NULL
)
4463 /* LWPs which will not be resumed are not interesting, because we
4464 might not wait for them next time through linux_wait. */
4469 debug_printf ("Need step over [LWP %ld]? Ignoring, not stopped\n",
4474 if (thread
->last_resume_kind
== resume_stop
)
4477 debug_printf ("Need step over [LWP %ld]? Ignoring, should remain"
4483 gdb_assert (lwp
->suspended
>= 0);
4488 debug_printf ("Need step over [LWP %ld]? Ignoring, suspended\n",
4493 if (lwp
->status_pending_p
)
4496 debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
4502 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
4506 /* If the PC has changed since we stopped, then don't do anything,
4507 and let the breakpoint/tracepoint be hit. This happens if, for
4508 instance, GDB handled the decr_pc_after_break subtraction itself,
4509 GDB is OOL stepping this thread, or the user has issued a "jump"
4510 command, or poked thread's registers herself. */
4511 if (pc
!= lwp
->stop_pc
)
4514 debug_printf ("Need step over [LWP %ld]? Cancelling, PC was changed. "
4515 "Old stop_pc was 0x%s, PC is now 0x%s\n",
4517 paddress (lwp
->stop_pc
), paddress (pc
));
4521 /* On software single step target, resume the inferior with signal
4522 rather than stepping over. */
4523 if (supports_software_single_step ()
4524 && !lwp
->pending_signals
.empty ()
4525 && lwp_signal_can_be_delivered (lwp
))
4528 debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
4535 saved_thread
= current_thread
;
4536 current_thread
= thread
;
4538 /* We can only step over breakpoints we know about. */
4539 if (breakpoint_here (pc
) || fast_tracepoint_jump_here (pc
))
4541 /* Don't step over a breakpoint that GDB expects to hit
4542 though. If the condition is being evaluated on the target's side
4543 and it evaluate to false, step over this breakpoint as well. */
4544 if (gdb_breakpoint_here (pc
)
4545 && gdb_condition_true_at_breakpoint (pc
)
4546 && gdb_no_commands_at_breakpoint (pc
))
4549 debug_printf ("Need step over [LWP %ld]? yes, but found"
4550 " GDB breakpoint at 0x%s; skipping step over\n",
4551 lwpid_of (thread
), paddress (pc
));
4553 current_thread
= saved_thread
;
4559 debug_printf ("Need step over [LWP %ld]? yes, "
4560 "found breakpoint at 0x%s\n",
4561 lwpid_of (thread
), paddress (pc
));
4563 /* We've found an lwp that needs stepping over --- return 1 so
4564 that find_thread stops looking. */
4565 current_thread
= saved_thread
;
4571 current_thread
= saved_thread
;
4574 debug_printf ("Need step over [LWP %ld]? No, no breakpoint found"
4576 lwpid_of (thread
), paddress (pc
));
4582 linux_process_target::start_step_over (lwp_info
*lwp
)
4584 struct thread_info
*thread
= get_lwp_thread (lwp
);
4585 struct thread_info
*saved_thread
;
4590 debug_printf ("Starting step-over on LWP %ld. Stopping all threads\n",
4593 stop_all_lwps (1, lwp
);
4595 if (lwp
->suspended
!= 0)
4597 internal_error (__FILE__
, __LINE__
,
4598 "LWP %ld suspended=%d\n", lwpid_of (thread
),
4603 debug_printf ("Done stopping all threads for step-over.\n");
4605 /* Note, we should always reach here with an already adjusted PC,
4606 either by GDB (if we're resuming due to GDB's request), or by our
4607 caller, if we just finished handling an internal breakpoint GDB
4608 shouldn't care about. */
4611 saved_thread
= current_thread
;
4612 current_thread
= thread
;
4614 lwp
->bp_reinsert
= pc
;
4615 uninsert_breakpoints_at (pc
);
4616 uninsert_fast_tracepoint_jumps_at (pc
);
4618 step
= single_step (lwp
);
4620 current_thread
= saved_thread
;
4622 resume_one_lwp (lwp
, step
, 0, NULL
);
4624 /* Require next event from this LWP. */
4625 step_over_bkpt
= thread
->id
;
4629 linux_process_target::finish_step_over (lwp_info
*lwp
)
4631 if (lwp
->bp_reinsert
!= 0)
4633 struct thread_info
*saved_thread
= current_thread
;
4636 debug_printf ("Finished step over.\n");
4638 current_thread
= get_lwp_thread (lwp
);
4640 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
4641 may be no breakpoint to reinsert there by now. */
4642 reinsert_breakpoints_at (lwp
->bp_reinsert
);
4643 reinsert_fast_tracepoint_jumps_at (lwp
->bp_reinsert
);
4645 lwp
->bp_reinsert
= 0;
4647 /* Delete any single-step breakpoints. No longer needed. We
4648 don't have to worry about other threads hitting this trap,
4649 and later not being able to explain it, because we were
4650 stepping over a breakpoint, and we hold all threads but
4651 LWP stopped while doing that. */
4652 if (!supports_hardware_single_step ())
4654 gdb_assert (has_single_step_breakpoints (current_thread
));
4655 delete_single_step_breakpoints (current_thread
);
4658 step_over_bkpt
= null_ptid
;
4659 current_thread
= saved_thread
;
4667 linux_process_target::complete_ongoing_step_over ()
4669 if (step_over_bkpt
!= null_ptid
)
4671 struct lwp_info
*lwp
;
4676 debug_printf ("detach: step over in progress, finish it first\n");
4678 /* Passing NULL_PTID as filter indicates we want all events to
4679 be left pending. Eventually this returns when there are no
4680 unwaited-for children left. */
4681 ret
= wait_for_event_filtered (minus_one_ptid
, null_ptid
, &wstat
,
4683 gdb_assert (ret
== -1);
4685 lwp
= find_lwp_pid (step_over_bkpt
);
4688 finish_step_over (lwp
);
4690 /* If we got our step SIGTRAP, don't leave it pending,
4691 otherwise we would report it to GDB as a spurious
4693 gdb_assert (lwp
->status_pending_p
);
4694 if (WIFSTOPPED (lwp
->status_pending
)
4695 && WSTOPSIG (lwp
->status_pending
) == SIGTRAP
)
4697 thread_info
*thread
= get_lwp_thread (lwp
);
4698 if (thread
->last_resume_kind
!= resume_step
)
4701 debug_printf ("detach: discard step-over SIGTRAP\n");
4703 lwp
->status_pending_p
= 0;
4704 lwp
->status_pending
= 0;
4705 resume_one_lwp (lwp
, lwp
->stepping
, 0, NULL
);
4710 debug_printf ("detach: resume_step, "
4711 "not discarding step-over SIGTRAP\n");
4715 step_over_bkpt
= null_ptid
;
4716 unsuspend_all_lwps (lwp
);
4721 linux_process_target::resume_one_thread (thread_info
*thread
,
4722 bool leave_all_stopped
)
4724 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4727 if (lwp
->resume
== NULL
)
4730 if (lwp
->resume
->kind
== resume_stop
)
4733 debug_printf ("resume_stop request for LWP %ld\n", lwpid_of (thread
));
4738 debug_printf ("stopping LWP %ld\n", lwpid_of (thread
));
4740 /* Stop the thread, and wait for the event asynchronously,
4741 through the event loop. */
4747 debug_printf ("already stopped LWP %ld\n",
4750 /* The LWP may have been stopped in an internal event that
4751 was not meant to be notified back to GDB (e.g., gdbserver
4752 breakpoint), so we should be reporting a stop event in
4755 /* If the thread already has a pending SIGSTOP, this is a
4756 no-op. Otherwise, something later will presumably resume
4757 the thread and this will cause it to cancel any pending
4758 operation, due to last_resume_kind == resume_stop. If
4759 the thread already has a pending status to report, we
4760 will still report it the next time we wait - see
4761 status_pending_p_callback. */
4763 /* If we already have a pending signal to report, then
4764 there's no need to queue a SIGSTOP, as this means we're
4765 midway through moving the LWP out of the jumppad, and we
4766 will report the pending signal as soon as that is
4768 if (lwp
->pending_signals_to_report
.empty ())
4772 /* For stop requests, we're done. */
4774 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
4778 /* If this thread which is about to be resumed has a pending status,
4779 then don't resume it - we can just report the pending status.
4780 Likewise if it is suspended, because e.g., another thread is
4781 stepping past a breakpoint. Make sure to queue any signals that
4782 would otherwise be sent. In all-stop mode, we do this decision
4783 based on if *any* thread has a pending status. If there's a
4784 thread that needs the step-over-breakpoint dance, then don't
4785 resume any other thread but that particular one. */
4786 leave_pending
= (lwp
->suspended
4787 || lwp
->status_pending_p
4788 || leave_all_stopped
);
4790 /* If we have a new signal, enqueue the signal. */
4791 if (lwp
->resume
->sig
!= 0)
4793 siginfo_t info
, *info_p
;
4795 /* If this is the same signal we were previously stopped by,
4796 make sure to queue its siginfo. */
4797 if (WIFSTOPPED (lwp
->last_status
)
4798 && WSTOPSIG (lwp
->last_status
) == lwp
->resume
->sig
4799 && ptrace (PTRACE_GETSIGINFO
, lwpid_of (thread
),
4800 (PTRACE_TYPE_ARG3
) 0, &info
) == 0)
4805 enqueue_pending_signal (lwp
, lwp
->resume
->sig
, info_p
);
4811 debug_printf ("resuming LWP %ld\n", lwpid_of (thread
));
4813 proceed_one_lwp (thread
, NULL
);
4818 debug_printf ("leaving LWP %ld stopped\n", lwpid_of (thread
));
4821 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
4826 linux_process_target::resume (thread_resume
*resume_info
, size_t n
)
4828 struct thread_info
*need_step_over
= NULL
;
4833 debug_printf ("linux_resume:\n");
4836 for_each_thread ([&] (thread_info
*thread
)
4838 linux_set_resume_request (thread
, resume_info
, n
);
4841 /* If there is a thread which would otherwise be resumed, which has
4842 a pending status, then don't resume any threads - we can just
4843 report the pending status. Make sure to queue any signals that
4844 would otherwise be sent. In non-stop mode, we'll apply this
4845 logic to each thread individually. We consume all pending events
4846 before considering to start a step-over (in all-stop). */
4847 bool any_pending
= false;
4849 any_pending
= find_thread ([this] (thread_info
*thread
)
4851 return resume_status_pending (thread
);
4854 /* If there is a thread which would otherwise be resumed, which is
4855 stopped at a breakpoint that needs stepping over, then don't
4856 resume any threads - have it step over the breakpoint with all
4857 other threads stopped, then resume all threads again. Make sure
4858 to queue any signals that would otherwise be delivered or
4860 if (!any_pending
&& low_supports_breakpoints ())
4861 need_step_over
= find_thread ([this] (thread_info
*thread
)
4863 return thread_needs_step_over (thread
);
4866 bool leave_all_stopped
= (need_step_over
!= NULL
|| any_pending
);
4870 if (need_step_over
!= NULL
)
4871 debug_printf ("Not resuming all, need step over\n");
4872 else if (any_pending
)
4873 debug_printf ("Not resuming, all-stop and found "
4874 "an LWP with pending status\n");
4876 debug_printf ("Resuming, no pending status or step over needed\n");
4879 /* Even if we're leaving threads stopped, queue all signals we'd
4880 otherwise deliver. */
4881 for_each_thread ([&] (thread_info
*thread
)
4883 resume_one_thread (thread
, leave_all_stopped
);
4887 start_step_over (get_thread_lwp (need_step_over
));
4891 debug_printf ("linux_resume done\n");
4895 /* We may have events that were pending that can/should be sent to
4896 the client now. Trigger a linux_wait call. */
4897 if (target_is_async_p ())
4902 linux_process_target::proceed_one_lwp (thread_info
*thread
, lwp_info
*except
)
4904 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4911 debug_printf ("proceed_one_lwp: lwp %ld\n", lwpid_of (thread
));
4916 debug_printf (" LWP %ld already running\n", lwpid_of (thread
));
4920 if (thread
->last_resume_kind
== resume_stop
4921 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
4924 debug_printf (" client wants LWP to remain %ld stopped\n",
4929 if (lwp
->status_pending_p
)
4932 debug_printf (" LWP %ld has pending status, leaving stopped\n",
4937 gdb_assert (lwp
->suspended
>= 0);
4942 debug_printf (" LWP %ld is suspended\n", lwpid_of (thread
));
4946 if (thread
->last_resume_kind
== resume_stop
4947 && lwp
->pending_signals_to_report
.empty ()
4948 && (lwp
->collecting_fast_tracepoint
4949 == fast_tpoint_collect_result::not_collecting
))
4951 /* We haven't reported this LWP as stopped yet (otherwise, the
4952 last_status.kind check above would catch it, and we wouldn't
4953 reach here. This LWP may have been momentarily paused by a
4954 stop_all_lwps call while handling for example, another LWP's
4955 step-over. In that case, the pending expected SIGSTOP signal
4956 that was queued at vCont;t handling time will have already
4957 been consumed by wait_for_sigstop, and so we need to requeue
4958 another one here. Note that if the LWP already has a SIGSTOP
4959 pending, this is a no-op. */
4962 debug_printf ("Client wants LWP %ld to stop. "
4963 "Making sure it has a SIGSTOP pending\n",
4969 if (thread
->last_resume_kind
== resume_step
)
4972 debug_printf (" stepping LWP %ld, client wants it stepping\n",
4975 /* If resume_step is requested by GDB, install single-step
4976 breakpoints when the thread is about to be actually resumed if
4977 the single-step breakpoints weren't removed. */
4978 if (supports_software_single_step ()
4979 && !has_single_step_breakpoints (thread
))
4980 install_software_single_step_breakpoints (lwp
);
4982 step
= maybe_hw_step (thread
);
4984 else if (lwp
->bp_reinsert
!= 0)
4987 debug_printf (" stepping LWP %ld, reinsert set\n",
4990 step
= maybe_hw_step (thread
);
4995 resume_one_lwp (lwp
, step
, 0, NULL
);
4999 linux_process_target::unsuspend_and_proceed_one_lwp (thread_info
*thread
,
5002 struct lwp_info
*lwp
= get_thread_lwp (thread
);
5007 lwp_suspended_decr (lwp
);
5009 proceed_one_lwp (thread
, except
);
5013 linux_process_target::proceed_all_lwps ()
5015 struct thread_info
*need_step_over
;
5017 /* If there is a thread which would otherwise be resumed, which is
5018 stopped at a breakpoint that needs stepping over, then don't
5019 resume any threads - have it step over the breakpoint with all
5020 other threads stopped, then resume all threads again. */
5022 if (low_supports_breakpoints ())
5024 need_step_over
= find_thread ([this] (thread_info
*thread
)
5026 return thread_needs_step_over (thread
);
5029 if (need_step_over
!= NULL
)
5032 debug_printf ("proceed_all_lwps: found "
5033 "thread %ld needing a step-over\n",
5034 lwpid_of (need_step_over
));
5036 start_step_over (get_thread_lwp (need_step_over
));
5042 debug_printf ("Proceeding, no step-over needed\n");
5044 for_each_thread ([this] (thread_info
*thread
)
5046 proceed_one_lwp (thread
, NULL
);
5051 linux_process_target::unstop_all_lwps (int unsuspend
, lwp_info
*except
)
5057 debug_printf ("unstopping all lwps, except=(LWP %ld)\n",
5058 lwpid_of (get_lwp_thread (except
)));
5060 debug_printf ("unstopping all lwps\n");
5064 for_each_thread ([&] (thread_info
*thread
)
5066 unsuspend_and_proceed_one_lwp (thread
, except
);
5069 for_each_thread ([&] (thread_info
*thread
)
5071 proceed_one_lwp (thread
, except
);
5076 debug_printf ("unstop_all_lwps done\n");
5082 #ifdef HAVE_LINUX_REGSETS
5084 #define use_linux_regsets 1
5086 /* Returns true if REGSET has been disabled. */
5089 regset_disabled (struct regsets_info
*info
, struct regset_info
*regset
)
5091 return (info
->disabled_regsets
!= NULL
5092 && info
->disabled_regsets
[regset
- info
->regsets
]);
5095 /* Disable REGSET. */
5098 disable_regset (struct regsets_info
*info
, struct regset_info
*regset
)
5102 dr_offset
= regset
- info
->regsets
;
5103 if (info
->disabled_regsets
== NULL
)
5104 info
->disabled_regsets
= (char *) xcalloc (1, info
->num_regsets
);
5105 info
->disabled_regsets
[dr_offset
] = 1;
5109 regsets_fetch_inferior_registers (struct regsets_info
*regsets_info
,
5110 struct regcache
*regcache
)
5112 struct regset_info
*regset
;
5113 int saw_general_regs
= 0;
5117 pid
= lwpid_of (current_thread
);
5118 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
5123 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
))
5126 buf
= xmalloc (regset
->size
);
5128 nt_type
= regset
->nt_type
;
5132 iov
.iov_len
= regset
->size
;
5133 data
= (void *) &iov
;
5139 res
= ptrace (regset
->get_request
, pid
,
5140 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5142 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
5147 || (errno
== EINVAL
&& regset
->type
== OPTIONAL_REGS
))
5149 /* If we get EIO on a regset, or an EINVAL and the regset is
5150 optional, do not try it again for this process mode. */
5151 disable_regset (regsets_info
, regset
);
5153 else if (errno
== ENODATA
)
5155 /* ENODATA may be returned if the regset is currently
5156 not "active". This can happen in normal operation,
5157 so suppress the warning in this case. */
5159 else if (errno
== ESRCH
)
5161 /* At this point, ESRCH should mean the process is
5162 already gone, in which case we simply ignore attempts
5163 to read its registers. */
5168 sprintf (s
, "ptrace(regsets_fetch_inferior_registers) PID=%d",
5175 if (regset
->type
== GENERAL_REGS
)
5176 saw_general_regs
= 1;
5177 regset
->store_function (regcache
, buf
);
5181 if (saw_general_regs
)
5188 regsets_store_inferior_registers (struct regsets_info
*regsets_info
,
5189 struct regcache
*regcache
)
5191 struct regset_info
*regset
;
5192 int saw_general_regs
= 0;
5196 pid
= lwpid_of (current_thread
);
5197 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
5202 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
)
5203 || regset
->fill_function
== NULL
)
5206 buf
= xmalloc (regset
->size
);
5208 /* First fill the buffer with the current register set contents,
5209 in case there are any items in the kernel's regset that are
5210 not in gdbserver's regcache. */
5212 nt_type
= regset
->nt_type
;
5216 iov
.iov_len
= regset
->size
;
5217 data
= (void *) &iov
;
5223 res
= ptrace (regset
->get_request
, pid
,
5224 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5226 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
5231 /* Then overlay our cached registers on that. */
5232 regset
->fill_function (regcache
, buf
);
5234 /* Only now do we write the register set. */
5236 res
= ptrace (regset
->set_request
, pid
,
5237 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5239 res
= ptrace (regset
->set_request
, pid
, data
, nt_type
);
5246 || (errno
== EINVAL
&& regset
->type
== OPTIONAL_REGS
))
5248 /* If we get EIO on a regset, or an EINVAL and the regset is
5249 optional, do not try it again for this process mode. */
5250 disable_regset (regsets_info
, regset
);
5252 else if (errno
== ESRCH
)
5254 /* At this point, ESRCH should mean the process is
5255 already gone, in which case we simply ignore attempts
5256 to change its registers. See also the related
5257 comment in resume_one_lwp. */
5263 perror ("Warning: ptrace(regsets_store_inferior_registers)");
5266 else if (regset
->type
== GENERAL_REGS
)
5267 saw_general_regs
= 1;
5270 if (saw_general_regs
)
5276 #else /* !HAVE_LINUX_REGSETS */
5278 #define use_linux_regsets 0
5279 #define regsets_fetch_inferior_registers(regsets_info, regcache) 1
5280 #define regsets_store_inferior_registers(regsets_info, regcache) 1
5284 /* Return 1 if register REGNO is supported by one of the regset ptrace
5285 calls or 0 if it has to be transferred individually. */
5288 linux_register_in_regsets (const struct regs_info
*regs_info
, int regno
)
5290 unsigned char mask
= 1 << (regno
% 8);
5291 size_t index
= regno
/ 8;
5293 return (use_linux_regsets
5294 && (regs_info
->regset_bitmap
== NULL
5295 || (regs_info
->regset_bitmap
[index
] & mask
) != 0));
5298 #ifdef HAVE_LINUX_USRREGS
5301 register_addr (const struct usrregs_info
*usrregs
, int regnum
)
5305 if (regnum
< 0 || regnum
>= usrregs
->num_regs
)
5306 error ("Invalid register number %d.", regnum
);
5308 addr
= usrregs
->regmap
[regnum
];
5315 linux_process_target::fetch_register (const usrregs_info
*usrregs
,
5316 regcache
*regcache
, int regno
)
5323 if (regno
>= usrregs
->num_regs
)
5325 if (low_cannot_fetch_register (regno
))
5328 regaddr
= register_addr (usrregs
, regno
);
5332 size
= ((register_size (regcache
->tdesc
, regno
)
5333 + sizeof (PTRACE_XFER_TYPE
) - 1)
5334 & -sizeof (PTRACE_XFER_TYPE
));
5335 buf
= (char *) alloca (size
);
5337 pid
= lwpid_of (current_thread
);
5338 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
5341 *(PTRACE_XFER_TYPE
*) (buf
+ i
) =
5342 ptrace (PTRACE_PEEKUSER
, pid
,
5343 /* Coerce to a uintptr_t first to avoid potential gcc warning
5344 of coercing an 8 byte integer to a 4 byte pointer. */
5345 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
, (PTRACE_TYPE_ARG4
) 0);
5346 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
5349 /* Mark register REGNO unavailable. */
5350 supply_register (regcache
, regno
, NULL
);
5355 low_supply_ptrace_register (regcache
, regno
, buf
);
5359 linux_process_target::store_register (const usrregs_info
*usrregs
,
5360 regcache
*regcache
, int regno
)
5367 if (regno
>= usrregs
->num_regs
)
5369 if (low_cannot_store_register (regno
))
5372 regaddr
= register_addr (usrregs
, regno
);
5376 size
= ((register_size (regcache
->tdesc
, regno
)
5377 + sizeof (PTRACE_XFER_TYPE
) - 1)
5378 & -sizeof (PTRACE_XFER_TYPE
));
5379 buf
= (char *) alloca (size
);
5380 memset (buf
, 0, size
);
5382 low_collect_ptrace_register (regcache
, regno
, buf
);
5384 pid
= lwpid_of (current_thread
);
5385 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
5388 ptrace (PTRACE_POKEUSER
, pid
,
5389 /* Coerce to a uintptr_t first to avoid potential gcc warning
5390 about coercing an 8 byte integer to a 4 byte pointer. */
5391 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
,
5392 (PTRACE_TYPE_ARG4
) *(PTRACE_XFER_TYPE
*) (buf
+ i
));
5395 /* At this point, ESRCH should mean the process is
5396 already gone, in which case we simply ignore attempts
5397 to change its registers. See also the related
5398 comment in resume_one_lwp. */
5403 if (!low_cannot_store_register (regno
))
5404 error ("writing register %d: %s", regno
, safe_strerror (errno
));
5406 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
5409 #endif /* HAVE_LINUX_USRREGS */
5412 linux_process_target::low_collect_ptrace_register (regcache
*regcache
,
5413 int regno
, char *buf
)
5415 collect_register (regcache
, regno
, buf
);
5419 linux_process_target::low_supply_ptrace_register (regcache
*regcache
,
5420 int regno
, const char *buf
)
5422 supply_register (regcache
, regno
, buf
);
5426 linux_process_target::usr_fetch_inferior_registers (const regs_info
*regs_info
,
5430 #ifdef HAVE_LINUX_USRREGS
5431 struct usrregs_info
*usr
= regs_info
->usrregs
;
5435 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
5436 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
5437 fetch_register (usr
, regcache
, regno
);
5440 fetch_register (usr
, regcache
, regno
);
5445 linux_process_target::usr_store_inferior_registers (const regs_info
*regs_info
,
5449 #ifdef HAVE_LINUX_USRREGS
5450 struct usrregs_info
*usr
= regs_info
->usrregs
;
5454 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
5455 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
5456 store_register (usr
, regcache
, regno
);
5459 store_register (usr
, regcache
, regno
);
5464 linux_process_target::fetch_registers (regcache
*regcache
, int regno
)
5468 const regs_info
*regs_info
= get_regs_info ();
5472 if (regs_info
->usrregs
!= NULL
)
5473 for (regno
= 0; regno
< regs_info
->usrregs
->num_regs
; regno
++)
5474 low_fetch_register (regcache
, regno
);
5476 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
, regcache
);
5477 if (regs_info
->usrregs
!= NULL
)
5478 usr_fetch_inferior_registers (regs_info
, regcache
, -1, all
);
5482 if (low_fetch_register (regcache
, regno
))
5485 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
5487 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
,
5489 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
5490 usr_fetch_inferior_registers (regs_info
, regcache
, regno
, 1);
5495 linux_process_target::store_registers (regcache
*regcache
, int regno
)
5499 const regs_info
*regs_info
= get_regs_info ();
5503 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
5505 if (regs_info
->usrregs
!= NULL
)
5506 usr_store_inferior_registers (regs_info
, regcache
, regno
, all
);
5510 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
5512 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
5514 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
5515 usr_store_inferior_registers (regs_info
, regcache
, regno
, 1);
5520 linux_process_target::low_fetch_register (regcache
*regcache
, int regno
)
5525 /* A wrapper for the read_memory target op. */
5528 linux_read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
, int len
)
5530 return the_target
->read_memory (memaddr
, myaddr
, len
);
5533 /* Copy LEN bytes from inferior's memory starting at MEMADDR
5534 to debugger memory starting at MYADDR. */
5537 linux_process_target::read_memory (CORE_ADDR memaddr
,
5538 unsigned char *myaddr
, int len
)
5540 int pid
= lwpid_of (current_thread
);
5541 PTRACE_XFER_TYPE
*buffer
;
5549 /* Try using /proc. Don't bother for one word. */
5550 if (len
>= 3 * sizeof (long))
5554 /* We could keep this file open and cache it - possibly one per
5555 thread. That requires some juggling, but is even faster. */
5556 sprintf (filename
, "/proc/%d/mem", pid
);
5557 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
5561 /* If pread64 is available, use it. It's faster if the kernel
5562 supports it (only one syscall), and it's 64-bit safe even on
5563 32-bit platforms (for instance, SPARC debugging a SPARC64
5566 bytes
= pread64 (fd
, myaddr
, len
, memaddr
);
5569 if (lseek (fd
, memaddr
, SEEK_SET
) != -1)
5570 bytes
= read (fd
, myaddr
, len
);
5577 /* Some data was read, we'll try to get the rest with ptrace. */
5587 /* Round starting address down to longword boundary. */
5588 addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
5589 /* Round ending address up; get number of longwords that makes. */
5590 count
= ((((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
5591 / sizeof (PTRACE_XFER_TYPE
));
5592 /* Allocate buffer of that many longwords. */
5593 buffer
= XALLOCAVEC (PTRACE_XFER_TYPE
, count
);
5595 /* Read all the longwords */
5597 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
5599 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5600 about coercing an 8 byte integer to a 4 byte pointer. */
5601 buffer
[i
] = ptrace (PTRACE_PEEKTEXT
, pid
,
5602 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5603 (PTRACE_TYPE_ARG4
) 0);
5609 /* Copy appropriate bytes out of the buffer. */
5612 i
*= sizeof (PTRACE_XFER_TYPE
);
5613 i
-= memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1);
5615 (char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
5622 /* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
5623 memory at MEMADDR. On failure (cannot write to the inferior)
5624 returns the value of errno. Always succeeds if LEN is zero. */
5627 linux_process_target::write_memory (CORE_ADDR memaddr
,
5628 const unsigned char *myaddr
, int len
)
5631 /* Round starting address down to longword boundary. */
5632 CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
5633 /* Round ending address up; get number of longwords that makes. */
5635 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
5636 / sizeof (PTRACE_XFER_TYPE
);
5638 /* Allocate buffer of that many longwords. */
5639 PTRACE_XFER_TYPE
*buffer
= XALLOCAVEC (PTRACE_XFER_TYPE
, count
);
5641 int pid
= lwpid_of (current_thread
);
5645 /* Zero length write always succeeds. */
5651 /* Dump up to four bytes. */
5652 char str
[4 * 2 + 1];
5654 int dump
= len
< 4 ? len
: 4;
5656 for (i
= 0; i
< dump
; i
++)
5658 sprintf (p
, "%02x", myaddr
[i
]);
5663 debug_printf ("Writing %s to 0x%08lx in process %d\n",
5664 str
, (long) memaddr
, pid
);
5667 /* Fill start and end extra bytes of buffer with existing memory data. */
5670 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5671 about coercing an 8 byte integer to a 4 byte pointer. */
5672 buffer
[0] = ptrace (PTRACE_PEEKTEXT
, pid
,
5673 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5674 (PTRACE_TYPE_ARG4
) 0);
5682 = ptrace (PTRACE_PEEKTEXT
, pid
,
5683 /* Coerce to a uintptr_t first to avoid potential gcc warning
5684 about coercing an 8 byte integer to a 4 byte pointer. */
5685 (PTRACE_TYPE_ARG3
) (uintptr_t) (addr
+ (count
- 1)
5686 * sizeof (PTRACE_XFER_TYPE
)),
5687 (PTRACE_TYPE_ARG4
) 0);
5692 /* Copy data to be written over corresponding part of buffer. */
5694 memcpy ((char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
5697 /* Write the entire buffer. */
5699 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
5702 ptrace (PTRACE_POKETEXT
, pid
,
5703 /* Coerce to a uintptr_t first to avoid potential gcc warning
5704 about coercing an 8 byte integer to a 4 byte pointer. */
5705 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5706 (PTRACE_TYPE_ARG4
) buffer
[i
]);
5715 linux_process_target::look_up_symbols ()
5717 #ifdef USE_THREAD_DB
5718 struct process_info
*proc
= current_process ();
5720 if (proc
->priv
->thread_db
!= NULL
)
5728 linux_process_target::request_interrupt ()
5730 /* Send a SIGINT to the process group. This acts just like the user
5731 typed a ^C on the controlling terminal. */
5732 ::kill (-signal_pid
, SIGINT
);
5736 linux_process_target::supports_read_auxv ()
5741 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
5742 to debugger memory starting at MYADDR. */
5745 linux_process_target::read_auxv (CORE_ADDR offset
, unsigned char *myaddr
,
5748 char filename
[PATH_MAX
];
5750 int pid
= lwpid_of (current_thread
);
5752 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
5754 fd
= open (filename
, O_RDONLY
);
5758 if (offset
!= (CORE_ADDR
) 0
5759 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
5762 n
= read (fd
, myaddr
, len
);
5770 linux_process_target::insert_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
5771 int size
, raw_breakpoint
*bp
)
5773 if (type
== raw_bkpt_type_sw
)
5774 return insert_memory_breakpoint (bp
);
5776 return low_insert_point (type
, addr
, size
, bp
);
5780 linux_process_target::low_insert_point (raw_bkpt_type type
, CORE_ADDR addr
,
5781 int size
, raw_breakpoint
*bp
)
5783 /* Unsupported (see target.h). */
5788 linux_process_target::remove_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
5789 int size
, raw_breakpoint
*bp
)
5791 if (type
== raw_bkpt_type_sw
)
5792 return remove_memory_breakpoint (bp
);
5794 return low_remove_point (type
, addr
, size
, bp
);
5798 linux_process_target::low_remove_point (raw_bkpt_type type
, CORE_ADDR addr
,
5799 int size
, raw_breakpoint
*bp
)
5801 /* Unsupported (see target.h). */
5805 /* Implement the stopped_by_sw_breakpoint target_ops
5809 linux_process_target::stopped_by_sw_breakpoint ()
5811 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5813 return (lwp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
);
5816 /* Implement the supports_stopped_by_sw_breakpoint target_ops
5820 linux_process_target::supports_stopped_by_sw_breakpoint ()
5822 return USE_SIGTRAP_SIGINFO
;
5825 /* Implement the stopped_by_hw_breakpoint target_ops
5829 linux_process_target::stopped_by_hw_breakpoint ()
5831 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5833 return (lwp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
);
5836 /* Implement the supports_stopped_by_hw_breakpoint target_ops
5840 linux_process_target::supports_stopped_by_hw_breakpoint ()
5842 return USE_SIGTRAP_SIGINFO
;
5845 /* Implement the supports_hardware_single_step target_ops method. */
5848 linux_process_target::supports_hardware_single_step ()
5854 linux_process_target::stopped_by_watchpoint ()
5856 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5858 return lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
;
5862 linux_process_target::stopped_data_address ()
5864 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5866 return lwp
->stopped_data_address
;
5869 /* This is only used for targets that define PT_TEXT_ADDR,
5870 PT_DATA_ADDR and PT_TEXT_END_ADDR. If those are not defined, supposedly
5871 the target has different ways of acquiring this information, like
5875 linux_process_target::supports_read_offsets ()
5877 #ifdef SUPPORTS_READ_OFFSETS
5884 /* Under uClinux, programs are loaded at non-zero offsets, which we need
5885 to tell gdb about. */
5888 linux_process_target::read_offsets (CORE_ADDR
*text_p
, CORE_ADDR
*data_p
)
5890 #ifdef SUPPORTS_READ_OFFSETS
5891 unsigned long text
, text_end
, data
;
5892 int pid
= lwpid_of (current_thread
);
5896 text
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_ADDR
,
5897 (PTRACE_TYPE_ARG4
) 0);
5898 text_end
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_END_ADDR
,
5899 (PTRACE_TYPE_ARG4
) 0);
5900 data
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_DATA_ADDR
,
5901 (PTRACE_TYPE_ARG4
) 0);
5905 /* Both text and data offsets produced at compile-time (and so
5906 used by gdb) are relative to the beginning of the program,
5907 with the data segment immediately following the text segment.
5908 However, the actual runtime layout in memory may put the data
5909 somewhere else, so when we send gdb a data base-address, we
5910 use the real data base address and subtract the compile-time
5911 data base-address from it (which is just the length of the
5912 text segment). BSS immediately follows data in both
5915 *data_p
= data
- (text_end
- text
);
5921 gdb_assert_not_reached ("target op read_offsets not supported");
5926 linux_process_target::supports_get_tls_address ()
5928 #ifdef USE_THREAD_DB
5936 linux_process_target::get_tls_address (thread_info
*thread
,
5938 CORE_ADDR load_module
,
5941 #ifdef USE_THREAD_DB
5942 return thread_db_get_tls_address (thread
, offset
, load_module
, address
);
5949 linux_process_target::supports_qxfer_osdata ()
5955 linux_process_target::qxfer_osdata (const char *annex
,
5956 unsigned char *readbuf
,
5957 unsigned const char *writebuf
,
5958 CORE_ADDR offset
, int len
)
5960 return linux_common_xfer_osdata (annex
, readbuf
, offset
, len
);
5964 linux_process_target::siginfo_fixup (siginfo_t
*siginfo
,
5965 gdb_byte
*inf_siginfo
, int direction
)
5967 bool done
= low_siginfo_fixup (siginfo
, inf_siginfo
, direction
);
5969 /* If there was no callback, or the callback didn't do anything,
5970 then just do a straight memcpy. */
5974 memcpy (siginfo
, inf_siginfo
, sizeof (siginfo_t
));
5976 memcpy (inf_siginfo
, siginfo
, sizeof (siginfo_t
));
5981 linux_process_target::low_siginfo_fixup (siginfo_t
*native
, gdb_byte
*inf
,
5988 linux_process_target::supports_qxfer_siginfo ()
5994 linux_process_target::qxfer_siginfo (const char *annex
,
5995 unsigned char *readbuf
,
5996 unsigned const char *writebuf
,
5997 CORE_ADDR offset
, int len
)
6001 gdb_byte inf_siginfo
[sizeof (siginfo_t
)];
6003 if (current_thread
== NULL
)
6006 pid
= lwpid_of (current_thread
);
6009 debug_printf ("%s siginfo for lwp %d.\n",
6010 readbuf
!= NULL
? "Reading" : "Writing",
6013 if (offset
>= sizeof (siginfo
))
6016 if (ptrace (PTRACE_GETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
6019 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
6020 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
6021 inferior with a 64-bit GDBSERVER should look the same as debugging it
6022 with a 32-bit GDBSERVER, we need to convert it. */
6023 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
6025 if (offset
+ len
> sizeof (siginfo
))
6026 len
= sizeof (siginfo
) - offset
;
6028 if (readbuf
!= NULL
)
6029 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
6032 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
6034 /* Convert back to ptrace layout before flushing it out. */
6035 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
6037 if (ptrace (PTRACE_SETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
6044 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
6045 so we notice when children change state; as the handler for the
6046 sigsuspend in my_waitpid. */
6049 sigchld_handler (int signo
)
6051 int old_errno
= errno
;
6057 /* Use the async signal safe debug function. */
6058 if (debug_write ("sigchld_handler\n",
6059 sizeof ("sigchld_handler\n") - 1) < 0)
6060 break; /* just ignore */
6064 if (target_is_async_p ())
6065 async_file_mark (); /* trigger a linux_wait */
6071 linux_process_target::supports_non_stop ()
6077 linux_process_target::async (bool enable
)
6079 bool previous
= target_is_async_p ();
6082 debug_printf ("linux_async (%d), previous=%d\n",
6085 if (previous
!= enable
)
6088 sigemptyset (&mask
);
6089 sigaddset (&mask
, SIGCHLD
);
6091 gdb_sigmask (SIG_BLOCK
, &mask
, NULL
);
6095 if (pipe (linux_event_pipe
) == -1)
6097 linux_event_pipe
[0] = -1;
6098 linux_event_pipe
[1] = -1;
6099 gdb_sigmask (SIG_UNBLOCK
, &mask
, NULL
);
6101 warning ("creating event pipe failed.");
6105 fcntl (linux_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
6106 fcntl (linux_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
6108 /* Register the event loop handler. */
6109 add_file_handler (linux_event_pipe
[0],
6110 handle_target_event
, NULL
,
6113 /* Always trigger a linux_wait. */
6118 delete_file_handler (linux_event_pipe
[0]);
6120 close (linux_event_pipe
[0]);
6121 close (linux_event_pipe
[1]);
6122 linux_event_pipe
[0] = -1;
6123 linux_event_pipe
[1] = -1;
6126 gdb_sigmask (SIG_UNBLOCK
, &mask
, NULL
);
6133 linux_process_target::start_non_stop (bool nonstop
)
6135 /* Register or unregister from event-loop accordingly. */
6136 target_async (nonstop
);
6138 if (target_is_async_p () != (nonstop
!= false))
6145 linux_process_target::supports_multi_process ()
6150 /* Check if fork events are supported. */
6153 linux_process_target::supports_fork_events ()
6155 return linux_supports_tracefork ();
6158 /* Check if vfork events are supported. */
6161 linux_process_target::supports_vfork_events ()
6163 return linux_supports_tracefork ();
6166 /* Check if exec events are supported. */
6169 linux_process_target::supports_exec_events ()
6171 return linux_supports_traceexec ();
6174 /* Target hook for 'handle_new_gdb_connection'. Causes a reset of the
6175 ptrace flags for all inferiors. This is in case the new GDB connection
6176 doesn't support the same set of events that the previous one did. */
6179 linux_process_target::handle_new_gdb_connection ()
6181 /* Request that all the lwps reset their ptrace options. */
6182 for_each_thread ([] (thread_info
*thread
)
6184 struct lwp_info
*lwp
= get_thread_lwp (thread
);
6188 /* Stop the lwp so we can modify its ptrace options. */
6189 lwp
->must_set_ptrace_flags
= 1;
6190 linux_stop_lwp (lwp
);
6194 /* Already stopped; go ahead and set the ptrace options. */
6195 struct process_info
*proc
= find_process_pid (pid_of (thread
));
6196 int options
= linux_low_ptrace_options (proc
->attached
);
6198 linux_enable_event_reporting (lwpid_of (thread
), options
);
6199 lwp
->must_set_ptrace_flags
= 0;
6205 linux_process_target::handle_monitor_command (char *mon
)
6207 #ifdef USE_THREAD_DB
6208 return thread_db_handle_monitor_command (mon
);
6215 linux_process_target::core_of_thread (ptid_t ptid
)
6217 return linux_common_core_of_thread (ptid
);
6221 linux_process_target::supports_disable_randomization ()
6227 linux_process_target::supports_agent ()
6233 linux_process_target::supports_range_stepping ()
6235 if (supports_software_single_step ())
6238 return low_supports_range_stepping ();
6242 linux_process_target::low_supports_range_stepping ()
6248 linux_process_target::supports_pid_to_exec_file ()
6254 linux_process_target::pid_to_exec_file (int pid
)
6256 return linux_proc_pid_to_exec_file (pid
);
6260 linux_process_target::supports_multifs ()
6266 linux_process_target::multifs_open (int pid
, const char *filename
,
6267 int flags
, mode_t mode
)
6269 return linux_mntns_open_cloexec (pid
, filename
, flags
, mode
);
6273 linux_process_target::multifs_unlink (int pid
, const char *filename
)
6275 return linux_mntns_unlink (pid
, filename
);
6279 linux_process_target::multifs_readlink (int pid
, const char *filename
,
6280 char *buf
, size_t bufsiz
)
6282 return linux_mntns_readlink (pid
, filename
, buf
, bufsiz
);
6285 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
6286 struct target_loadseg
6288 /* Core address to which the segment is mapped. */
6290 /* VMA recorded in the program header. */
6292 /* Size of this segment in memory. */
6296 # if defined PT_GETDSBT
6297 struct target_loadmap
6299 /* Protocol version number, must be zero. */
6301 /* Pointer to the DSBT table, its size, and the DSBT index. */
6302 unsigned *dsbt_table
;
6303 unsigned dsbt_size
, dsbt_index
;
6304 /* Number of segments in this map. */
6306 /* The actual memory map. */
6307 struct target_loadseg segs
[/*nsegs*/];
6309 # define LINUX_LOADMAP PT_GETDSBT
6310 # define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
6311 # define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
6313 struct target_loadmap
6315 /* Protocol version number, must be zero. */
6317 /* Number of segments in this map. */
6319 /* The actual memory map. */
6320 struct target_loadseg segs
[/*nsegs*/];
6322 # define LINUX_LOADMAP PTRACE_GETFDPIC
6323 # define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
6324 # define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
6328 linux_process_target::supports_read_loadmap ()
6334 linux_process_target::read_loadmap (const char *annex
, CORE_ADDR offset
,
6335 unsigned char *myaddr
, unsigned int len
)
6337 int pid
= lwpid_of (current_thread
);
6339 struct target_loadmap
*data
= NULL
;
6340 unsigned int actual_length
, copy_length
;
6342 if (strcmp (annex
, "exec") == 0)
6343 addr
= (int) LINUX_LOADMAP_EXEC
;
6344 else if (strcmp (annex
, "interp") == 0)
6345 addr
= (int) LINUX_LOADMAP_INTERP
;
6349 if (ptrace (LINUX_LOADMAP
, pid
, addr
, &data
) != 0)
6355 actual_length
= sizeof (struct target_loadmap
)
6356 + sizeof (struct target_loadseg
) * data
->nsegs
;
6358 if (offset
< 0 || offset
> actual_length
)
6361 copy_length
= actual_length
- offset
< len
? actual_length
- offset
: len
;
6362 memcpy (myaddr
, (char *) data
+ offset
, copy_length
);
6365 #endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
6368 linux_process_target::supports_catch_syscall ()
6370 return (low_supports_catch_syscall ()
6371 && linux_supports_tracesysgood ());
6375 linux_process_target::low_supports_catch_syscall ()
6381 linux_process_target::read_pc (regcache
*regcache
)
6383 if (!low_supports_breakpoints ())
6386 return low_get_pc (regcache
);
6390 linux_process_target::write_pc (regcache
*regcache
, CORE_ADDR pc
)
6392 gdb_assert (low_supports_breakpoints ());
6394 low_set_pc (regcache
, pc
);
6398 linux_process_target::supports_thread_stopped ()
6404 linux_process_target::thread_stopped (thread_info
*thread
)
6406 return get_thread_lwp (thread
)->stopped
;
6409 /* This exposes stop-all-threads functionality to other modules. */
6412 linux_process_target::pause_all (bool freeze
)
6414 stop_all_lwps (freeze
, NULL
);
6417 /* This exposes unstop-all-threads functionality to other gdbserver
6421 linux_process_target::unpause_all (bool unfreeze
)
6423 unstop_all_lwps (unfreeze
, NULL
);
6427 linux_process_target::prepare_to_access_memory ()
6429 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6432 target_pause_all (true);
6437 linux_process_target::done_accessing_memory ()
6439 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6442 target_unpause_all (true);
6445 /* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
6448 get_phdr_phnum_from_proc_auxv (const int pid
, const int is_elf64
,
6449 CORE_ADDR
*phdr_memaddr
, int *num_phdr
)
6451 char filename
[PATH_MAX
];
6453 const int auxv_size
= is_elf64
6454 ? sizeof (Elf64_auxv_t
) : sizeof (Elf32_auxv_t
);
6455 char buf
[sizeof (Elf64_auxv_t
)]; /* The larger of the two. */
6457 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
6459 fd
= open (filename
, O_RDONLY
);
6465 while (read (fd
, buf
, auxv_size
) == auxv_size
6466 && (*phdr_memaddr
== 0 || *num_phdr
== 0))
6470 Elf64_auxv_t
*const aux
= (Elf64_auxv_t
*) buf
;
6472 switch (aux
->a_type
)
6475 *phdr_memaddr
= aux
->a_un
.a_val
;
6478 *num_phdr
= aux
->a_un
.a_val
;
6484 Elf32_auxv_t
*const aux
= (Elf32_auxv_t
*) buf
;
6486 switch (aux
->a_type
)
6489 *phdr_memaddr
= aux
->a_un
.a_val
;
6492 *num_phdr
= aux
->a_un
.a_val
;
6500 if (*phdr_memaddr
== 0 || *num_phdr
== 0)
6502 warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
6503 "phdr_memaddr = %ld, phdr_num = %d",
6504 (long) *phdr_memaddr
, *num_phdr
);
6511 /* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
6514 get_dynamic (const int pid
, const int is_elf64
)
6516 CORE_ADDR phdr_memaddr
, relocation
;
6518 unsigned char *phdr_buf
;
6519 const int phdr_size
= is_elf64
? sizeof (Elf64_Phdr
) : sizeof (Elf32_Phdr
);
6521 if (get_phdr_phnum_from_proc_auxv (pid
, is_elf64
, &phdr_memaddr
, &num_phdr
))
6524 gdb_assert (num_phdr
< 100); /* Basic sanity check. */
6525 phdr_buf
= (unsigned char *) alloca (num_phdr
* phdr_size
);
6527 if (linux_read_memory (phdr_memaddr
, phdr_buf
, num_phdr
* phdr_size
))
6530 /* Compute relocation: it is expected to be 0 for "regular" executables,
6531 non-zero for PIE ones. */
6533 for (i
= 0; relocation
== -1 && i
< num_phdr
; i
++)
6536 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6538 if (p
->p_type
== PT_PHDR
)
6539 relocation
= phdr_memaddr
- p
->p_vaddr
;
6543 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6545 if (p
->p_type
== PT_PHDR
)
6546 relocation
= phdr_memaddr
- p
->p_vaddr
;
6549 if (relocation
== -1)
6551 /* PT_PHDR is optional, but necessary for PIE in general. Fortunately
6552 any real world executables, including PIE executables, have always
6553 PT_PHDR present. PT_PHDR is not present in some shared libraries or
6554 in fpc (Free Pascal 2.4) binaries but neither of those have a need for
6555 or present DT_DEBUG anyway (fpc binaries are statically linked).
6557 Therefore if there exists DT_DEBUG there is always also PT_PHDR.
6559 GDB could find RELOCATION also from AT_ENTRY - e_entry. */
6564 for (i
= 0; i
< num_phdr
; i
++)
6568 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6570 if (p
->p_type
== PT_DYNAMIC
)
6571 return p
->p_vaddr
+ relocation
;
6575 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6577 if (p
->p_type
== PT_DYNAMIC
)
6578 return p
->p_vaddr
+ relocation
;
6585 /* Return &_r_debug in the inferior, or -1 if not present. Return value
6586 can be 0 if the inferior does not yet have the library list initialized.
6587 We look for DT_MIPS_RLD_MAP first. MIPS executables use this instead of
6588 DT_DEBUG, although they sometimes contain an unused DT_DEBUG entry too. */
6591 get_r_debug (const int pid
, const int is_elf64
)
6593 CORE_ADDR dynamic_memaddr
;
6594 const int dyn_size
= is_elf64
? sizeof (Elf64_Dyn
) : sizeof (Elf32_Dyn
);
6595 unsigned char buf
[sizeof (Elf64_Dyn
)]; /* The larger of the two. */
6598 dynamic_memaddr
= get_dynamic (pid
, is_elf64
);
6599 if (dynamic_memaddr
== 0)
6602 while (linux_read_memory (dynamic_memaddr
, buf
, dyn_size
) == 0)
6606 Elf64_Dyn
*const dyn
= (Elf64_Dyn
*) buf
;
6607 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
6611 unsigned char buf
[sizeof (Elf64_Xword
)];
6615 #ifdef DT_MIPS_RLD_MAP
6616 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
6618 if (linux_read_memory (dyn
->d_un
.d_val
,
6619 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6624 #endif /* DT_MIPS_RLD_MAP */
6625 #ifdef DT_MIPS_RLD_MAP_REL
6626 if (dyn
->d_tag
== DT_MIPS_RLD_MAP_REL
)
6628 if (linux_read_memory (dyn
->d_un
.d_val
+ dynamic_memaddr
,
6629 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6634 #endif /* DT_MIPS_RLD_MAP_REL */
6636 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
6637 map
= dyn
->d_un
.d_val
;
6639 if (dyn
->d_tag
== DT_NULL
)
6644 Elf32_Dyn
*const dyn
= (Elf32_Dyn
*) buf
;
6645 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
6649 unsigned char buf
[sizeof (Elf32_Word
)];
6653 #ifdef DT_MIPS_RLD_MAP
6654 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
6656 if (linux_read_memory (dyn
->d_un
.d_val
,
6657 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6662 #endif /* DT_MIPS_RLD_MAP */
6663 #ifdef DT_MIPS_RLD_MAP_REL
6664 if (dyn
->d_tag
== DT_MIPS_RLD_MAP_REL
)
6666 if (linux_read_memory (dyn
->d_un
.d_val
+ dynamic_memaddr
,
6667 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6672 #endif /* DT_MIPS_RLD_MAP_REL */
6674 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
6675 map
= dyn
->d_un
.d_val
;
6677 if (dyn
->d_tag
== DT_NULL
)
6681 dynamic_memaddr
+= dyn_size
;
6687 /* Read one pointer from MEMADDR in the inferior. */
6690 read_one_ptr (CORE_ADDR memaddr
, CORE_ADDR
*ptr
, int ptr_size
)
6694 /* Go through a union so this works on either big or little endian
6695 hosts, when the inferior's pointer size is smaller than the size
6696 of CORE_ADDR. It is assumed the inferior's endianness is the
6697 same of the superior's. */
6700 CORE_ADDR core_addr
;
6705 ret
= linux_read_memory (memaddr
, &addr
.uc
, ptr_size
);
6708 if (ptr_size
== sizeof (CORE_ADDR
))
6709 *ptr
= addr
.core_addr
;
6710 else if (ptr_size
== sizeof (unsigned int))
6713 gdb_assert_not_reached ("unhandled pointer size");
6719 linux_process_target::supports_qxfer_libraries_svr4 ()
6724 struct link_map_offsets
6726 /* Offset and size of r_debug.r_version. */
6727 int r_version_offset
;
6729 /* Offset and size of r_debug.r_map. */
6732 /* Offset to l_addr field in struct link_map. */
6735 /* Offset to l_name field in struct link_map. */
6738 /* Offset to l_ld field in struct link_map. */
6741 /* Offset to l_next field in struct link_map. */
6744 /* Offset to l_prev field in struct link_map. */
6748 /* Construct qXfer:libraries-svr4:read reply. */
6751 linux_process_target::qxfer_libraries_svr4 (const char *annex
,
6752 unsigned char *readbuf
,
6753 unsigned const char *writebuf
,
6754 CORE_ADDR offset
, int len
)
6756 struct process_info_private
*const priv
= current_process ()->priv
;
6757 char filename
[PATH_MAX
];
6760 static const struct link_map_offsets lmo_32bit_offsets
=
6762 0, /* r_version offset. */
6763 4, /* r_debug.r_map offset. */
6764 0, /* l_addr offset in link_map. */
6765 4, /* l_name offset in link_map. */
6766 8, /* l_ld offset in link_map. */
6767 12, /* l_next offset in link_map. */
6768 16 /* l_prev offset in link_map. */
6771 static const struct link_map_offsets lmo_64bit_offsets
=
6773 0, /* r_version offset. */
6774 8, /* r_debug.r_map offset. */
6775 0, /* l_addr offset in link_map. */
6776 8, /* l_name offset in link_map. */
6777 16, /* l_ld offset in link_map. */
6778 24, /* l_next offset in link_map. */
6779 32 /* l_prev offset in link_map. */
6781 const struct link_map_offsets
*lmo
;
6782 unsigned int machine
;
6784 CORE_ADDR lm_addr
= 0, lm_prev
= 0;
6785 CORE_ADDR l_name
, l_addr
, l_ld
, l_next
, l_prev
;
6786 int header_done
= 0;
6788 if (writebuf
!= NULL
)
6790 if (readbuf
== NULL
)
6793 pid
= lwpid_of (current_thread
);
6794 xsnprintf (filename
, sizeof filename
, "/proc/%d/exe", pid
);
6795 is_elf64
= elf_64_file_p (filename
, &machine
);
6796 lmo
= is_elf64
? &lmo_64bit_offsets
: &lmo_32bit_offsets
;
6797 ptr_size
= is_elf64
? 8 : 4;
6799 while (annex
[0] != '\0')
6805 sep
= strchr (annex
, '=');
6809 name_len
= sep
- annex
;
6810 if (name_len
== 5 && startswith (annex
, "start"))
6812 else if (name_len
== 4 && startswith (annex
, "prev"))
6816 annex
= strchr (sep
, ';');
6823 annex
= decode_address_to_semicolon (addrp
, sep
+ 1);
6830 if (priv
->r_debug
== 0)
6831 priv
->r_debug
= get_r_debug (pid
, is_elf64
);
6833 /* We failed to find DT_DEBUG. Such situation will not change
6834 for this inferior - do not retry it. Report it to GDB as
6835 E01, see for the reasons at the GDB solib-svr4.c side. */
6836 if (priv
->r_debug
== (CORE_ADDR
) -1)
6839 if (priv
->r_debug
!= 0)
6841 if (linux_read_memory (priv
->r_debug
+ lmo
->r_version_offset
,
6842 (unsigned char *) &r_version
,
6843 sizeof (r_version
)) != 0
6846 warning ("unexpected r_debug version %d", r_version
);
6848 else if (read_one_ptr (priv
->r_debug
+ lmo
->r_map_offset
,
6849 &lm_addr
, ptr_size
) != 0)
6851 warning ("unable to read r_map from 0x%lx",
6852 (long) priv
->r_debug
+ lmo
->r_map_offset
);
6857 std::string document
= "<library-list-svr4 version=\"1.0\"";
6860 && read_one_ptr (lm_addr
+ lmo
->l_name_offset
,
6861 &l_name
, ptr_size
) == 0
6862 && read_one_ptr (lm_addr
+ lmo
->l_addr_offset
,
6863 &l_addr
, ptr_size
) == 0
6864 && read_one_ptr (lm_addr
+ lmo
->l_ld_offset
,
6865 &l_ld
, ptr_size
) == 0
6866 && read_one_ptr (lm_addr
+ lmo
->l_prev_offset
,
6867 &l_prev
, ptr_size
) == 0
6868 && read_one_ptr (lm_addr
+ lmo
->l_next_offset
,
6869 &l_next
, ptr_size
) == 0)
6871 unsigned char libname
[PATH_MAX
];
6873 if (lm_prev
!= l_prev
)
6875 warning ("Corrupted shared library list: 0x%lx != 0x%lx",
6876 (long) lm_prev
, (long) l_prev
);
6880 /* Ignore the first entry even if it has valid name as the first entry
6881 corresponds to the main executable. The first entry should not be
6882 skipped if the dynamic loader was loaded late by a static executable
6883 (see solib-svr4.c parameter ignore_first). But in such case the main
6884 executable does not have PT_DYNAMIC present and this function already
6885 exited above due to failed get_r_debug. */
6887 string_appendf (document
, " main-lm=\"0x%lx\"", (unsigned long) lm_addr
);
6890 /* Not checking for error because reading may stop before
6891 we've got PATH_MAX worth of characters. */
6893 linux_read_memory (l_name
, libname
, sizeof (libname
) - 1);
6894 libname
[sizeof (libname
) - 1] = '\0';
6895 if (libname
[0] != '\0')
6899 /* Terminate `<library-list-svr4'. */
6904 string_appendf (document
, "<library name=\"");
6905 xml_escape_text_append (&document
, (char *) libname
);
6906 string_appendf (document
, "\" lm=\"0x%lx\" "
6907 "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
6908 (unsigned long) lm_addr
, (unsigned long) l_addr
,
6909 (unsigned long) l_ld
);
6919 /* Empty list; terminate `<library-list-svr4'. */
6923 document
+= "</library-list-svr4>";
6925 int document_len
= document
.length ();
6926 if (offset
< document_len
)
6927 document_len
-= offset
;
6930 if (len
> document_len
)
6933 memcpy (readbuf
, document
.data () + offset
, len
);
6938 #ifdef HAVE_LINUX_BTRACE
6940 btrace_target_info
*
6941 linux_process_target::enable_btrace (ptid_t ptid
,
6942 const btrace_config
*conf
)
6944 return linux_enable_btrace (ptid
, conf
);
6947 /* See to_disable_btrace target method. */
6950 linux_process_target::disable_btrace (btrace_target_info
*tinfo
)
6952 enum btrace_error err
;
6954 err
= linux_disable_btrace (tinfo
);
6955 return (err
== BTRACE_ERR_NONE
? 0 : -1);
6958 /* Encode an Intel Processor Trace configuration. */
6961 linux_low_encode_pt_config (struct buffer
*buffer
,
6962 const struct btrace_data_pt_config
*config
)
6964 buffer_grow_str (buffer
, "<pt-config>\n");
6966 switch (config
->cpu
.vendor
)
6969 buffer_xml_printf (buffer
, "<cpu vendor=\"GenuineIntel\" family=\"%u\" "
6970 "model=\"%u\" stepping=\"%u\"/>\n",
6971 config
->cpu
.family
, config
->cpu
.model
,
6972 config
->cpu
.stepping
);
6979 buffer_grow_str (buffer
, "</pt-config>\n");
6982 /* Encode a raw buffer. */
6985 linux_low_encode_raw (struct buffer
*buffer
, const gdb_byte
*data
,
6991 /* We use hex encoding - see gdbsupport/rsp-low.h. */
6992 buffer_grow_str (buffer
, "<raw>\n");
6998 elem
[0] = tohex ((*data
>> 4) & 0xf);
6999 elem
[1] = tohex (*data
++ & 0xf);
7001 buffer_grow (buffer
, elem
, 2);
7004 buffer_grow_str (buffer
, "</raw>\n");
7007 /* See to_read_btrace target method. */
7010 linux_process_target::read_btrace (btrace_target_info
*tinfo
,
7012 enum btrace_read_type type
)
7014 struct btrace_data btrace
;
7015 enum btrace_error err
;
7017 err
= linux_read_btrace (&btrace
, tinfo
, type
);
7018 if (err
!= BTRACE_ERR_NONE
)
7020 if (err
== BTRACE_ERR_OVERFLOW
)
7021 buffer_grow_str0 (buffer
, "E.Overflow.");
7023 buffer_grow_str0 (buffer
, "E.Generic Error.");
7028 switch (btrace
.format
)
7030 case BTRACE_FORMAT_NONE
:
7031 buffer_grow_str0 (buffer
, "E.No Trace.");
7034 case BTRACE_FORMAT_BTS
:
7035 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
7036 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
7038 for (const btrace_block
&block
: *btrace
.variant
.bts
.blocks
)
7039 buffer_xml_printf (buffer
, "<block begin=\"0x%s\" end=\"0x%s\"/>\n",
7040 paddress (block
.begin
), paddress (block
.end
));
7042 buffer_grow_str0 (buffer
, "</btrace>\n");
7045 case BTRACE_FORMAT_PT
:
7046 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
7047 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
7048 buffer_grow_str (buffer
, "<pt>\n");
7050 linux_low_encode_pt_config (buffer
, &btrace
.variant
.pt
.config
);
7052 linux_low_encode_raw (buffer
, btrace
.variant
.pt
.data
,
7053 btrace
.variant
.pt
.size
);
7055 buffer_grow_str (buffer
, "</pt>\n");
7056 buffer_grow_str0 (buffer
, "</btrace>\n");
7060 buffer_grow_str0 (buffer
, "E.Unsupported Trace Format.");
7067 /* See to_btrace_conf target method. */
7070 linux_process_target::read_btrace_conf (const btrace_target_info
*tinfo
,
7073 const struct btrace_config
*conf
;
7075 buffer_grow_str (buffer
, "<!DOCTYPE btrace-conf SYSTEM \"btrace-conf.dtd\">\n");
7076 buffer_grow_str (buffer
, "<btrace-conf version=\"1.0\">\n");
7078 conf
= linux_btrace_conf (tinfo
);
7081 switch (conf
->format
)
7083 case BTRACE_FORMAT_NONE
:
7086 case BTRACE_FORMAT_BTS
:
7087 buffer_xml_printf (buffer
, "<bts");
7088 buffer_xml_printf (buffer
, " size=\"0x%x\"", conf
->bts
.size
);
7089 buffer_xml_printf (buffer
, " />\n");
7092 case BTRACE_FORMAT_PT
:
7093 buffer_xml_printf (buffer
, "<pt");
7094 buffer_xml_printf (buffer
, " size=\"0x%x\"", conf
->pt
.size
);
7095 buffer_xml_printf (buffer
, "/>\n");
7100 buffer_grow_str0 (buffer
, "</btrace-conf>\n");
7103 #endif /* HAVE_LINUX_BTRACE */
7105 /* See nat/linux-nat.h. */
7108 current_lwp_ptid (void)
7110 return ptid_of (current_thread
);
7114 linux_process_target::thread_name (ptid_t thread
)
7116 return linux_proc_tid_get_name (thread
);
7121 linux_process_target::thread_handle (ptid_t ptid
, gdb_byte
**handle
,
7124 return thread_db_thread_handle (ptid
, handle
, handle_len
);
7129 linux_process_target::thread_pending_parent (thread_info
*thread
)
7131 lwp_info
*parent
= get_thread_lwp (thread
)->pending_parent ();
7133 if (parent
== nullptr)
7136 return get_lwp_thread (parent
);
7139 /* Default implementation of linux_target_ops method "set_pc" for
7140 32-bit pc register which is literally named "pc". */
7143 linux_set_pc_32bit (struct regcache
*regcache
, CORE_ADDR pc
)
7145 uint32_t newpc
= pc
;
7147 supply_register_by_name (regcache
, "pc", &newpc
);
7150 /* Default implementation of linux_target_ops method "get_pc" for
7151 32-bit pc register which is literally named "pc". */
7154 linux_get_pc_32bit (struct regcache
*regcache
)
7158 collect_register_by_name (regcache
, "pc", &pc
);
7160 debug_printf ("stop pc is 0x%" PRIx32
"\n", pc
);
7164 /* Default implementation of linux_target_ops method "set_pc" for
7165 64-bit pc register which is literally named "pc". */
7168 linux_set_pc_64bit (struct regcache
*regcache
, CORE_ADDR pc
)
7170 uint64_t newpc
= pc
;
7172 supply_register_by_name (regcache
, "pc", &newpc
);
7175 /* Default implementation of linux_target_ops method "get_pc" for
7176 64-bit pc register which is literally named "pc". */
7179 linux_get_pc_64bit (struct regcache
*regcache
)
7183 collect_register_by_name (regcache
, "pc", &pc
);
7185 debug_printf ("stop pc is 0x%" PRIx64
"\n", pc
);
7189 /* See linux-low.h. */
7192 linux_get_auxv (int wordsize
, CORE_ADDR match
, CORE_ADDR
*valp
)
7194 gdb_byte
*data
= (gdb_byte
*) alloca (2 * wordsize
);
7197 gdb_assert (wordsize
== 4 || wordsize
== 8);
7199 while (the_target
->read_auxv (offset
, data
, 2 * wordsize
) == 2 * wordsize
)
7203 uint32_t *data_p
= (uint32_t *) data
;
7204 if (data_p
[0] == match
)
7212 uint64_t *data_p
= (uint64_t *) data
;
7213 if (data_p
[0] == match
)
7220 offset
+= 2 * wordsize
;
7226 /* See linux-low.h. */
7229 linux_get_hwcap (int wordsize
)
7231 CORE_ADDR hwcap
= 0;
7232 linux_get_auxv (wordsize
, AT_HWCAP
, &hwcap
);
7236 /* See linux-low.h. */
7239 linux_get_hwcap2 (int wordsize
)
7241 CORE_ADDR hwcap2
= 0;
7242 linux_get_auxv (wordsize
, AT_HWCAP2
, &hwcap2
);
7246 #ifdef HAVE_LINUX_REGSETS
7248 initialize_regsets_info (struct regsets_info
*info
)
7250 for (info
->num_regsets
= 0;
7251 info
->regsets
[info
->num_regsets
].size
>= 0;
7252 info
->num_regsets
++)
7258 initialize_low (void)
7260 struct sigaction sigchld_action
;
7262 memset (&sigchld_action
, 0, sizeof (sigchld_action
));
7263 set_target_ops (the_linux_target
);
7265 linux_ptrace_init_warnings ();
7266 linux_proc_init_warnings ();
7268 sigchld_action
.sa_handler
= sigchld_handler
;
7269 sigemptyset (&sigchld_action
.sa_mask
);
7270 sigchld_action
.sa_flags
= SA_RESTART
;
7271 sigaction (SIGCHLD
, &sigchld_action
, NULL
);
7273 initialize_low_arch ();
7275 linux_check_ptrace_features ();