1 /* Low level interface to ptrace, for the remote server for GDB.
2 Copyright (C) 1995-2020 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"
63 #ifdef HAVE_PERSONALITY
64 # include <sys/personality.h>
65 # if !HAVE_DECL_ADDR_NO_RANDOMIZE
66 # define ADDR_NO_RANDOMIZE 0x0040000
78 /* Some targets did not define these ptrace constants from the start,
79 so gdbserver defines them locally here. In the future, these may
80 be removed after they are added to asm/ptrace.h. */
81 #if !(defined(PT_TEXT_ADDR) \
82 || defined(PT_DATA_ADDR) \
83 || defined(PT_TEXT_END_ADDR))
84 #if defined(__mcoldfire__)
85 /* These are still undefined in 3.10 kernels. */
86 #define PT_TEXT_ADDR 49*4
87 #define PT_DATA_ADDR 50*4
88 #define PT_TEXT_END_ADDR 51*4
89 /* These are still undefined in 3.10 kernels. */
90 #elif defined(__TMS320C6X__)
91 #define PT_TEXT_ADDR (0x10000*4)
92 #define PT_DATA_ADDR (0x10004*4)
93 #define PT_TEXT_END_ADDR (0x10008*4)
97 #if (defined(__UCLIBC__) \
98 && defined(HAS_NOMMU) \
99 && defined(PT_TEXT_ADDR) \
100 && defined(PT_DATA_ADDR) \
101 && defined(PT_TEXT_END_ADDR))
102 #define SUPPORTS_READ_OFFSETS
105 #ifdef HAVE_LINUX_BTRACE
106 # include "nat/linux-btrace.h"
107 # include "gdbsupport/btrace-common.h"
110 #ifndef HAVE_ELF32_AUXV_T
111 /* Copied from glibc's elf.h. */
114 uint32_t a_type
; /* Entry type */
117 uint32_t a_val
; /* Integer value */
118 /* We use to have pointer elements added here. We cannot do that,
119 though, since it does not work when using 32-bit definitions
120 on 64-bit platforms and vice versa. */
125 #ifndef HAVE_ELF64_AUXV_T
126 /* Copied from glibc's elf.h. */
129 uint64_t a_type
; /* Entry type */
132 uint64_t a_val
; /* Integer value */
133 /* We use to have pointer elements added here. We cannot do that,
134 though, since it does not work when using 32-bit definitions
135 on 64-bit platforms and vice versa. */
140 /* Does the current host support PTRACE_GETREGSET? */
141 int have_ptrace_getregset
= -1;
145 /* See nat/linux-nat.h. */
148 ptid_of_lwp (struct lwp_info
*lwp
)
150 return ptid_of (get_lwp_thread (lwp
));
153 /* See nat/linux-nat.h. */
156 lwp_set_arch_private_info (struct lwp_info
*lwp
,
157 struct arch_lwp_info
*info
)
159 lwp
->arch_private
= info
;
162 /* See nat/linux-nat.h. */
164 struct arch_lwp_info
*
165 lwp_arch_private_info (struct lwp_info
*lwp
)
167 return lwp
->arch_private
;
170 /* See nat/linux-nat.h. */
173 lwp_is_stopped (struct lwp_info
*lwp
)
178 /* See nat/linux-nat.h. */
180 enum target_stop_reason
181 lwp_stop_reason (struct lwp_info
*lwp
)
183 return lwp
->stop_reason
;
186 /* See nat/linux-nat.h. */
189 lwp_is_stepping (struct lwp_info
*lwp
)
191 return lwp
->stepping
;
194 /* A list of all unknown processes which receive stop signals. Some
195 other process will presumably claim each of these as forked
196 children momentarily. */
198 struct simple_pid_list
200 /* The process ID. */
203 /* The status as reported by waitpid. */
207 struct simple_pid_list
*next
;
209 struct simple_pid_list
*stopped_pids
;
211 /* Trivial list manipulation functions to keep track of a list of new
212 stopped processes. */
215 add_to_pid_list (struct simple_pid_list
**listp
, int pid
, int status
)
217 struct simple_pid_list
*new_pid
= XNEW (struct simple_pid_list
);
220 new_pid
->status
= status
;
221 new_pid
->next
= *listp
;
226 pull_pid_from_list (struct simple_pid_list
**listp
, int pid
, int *statusp
)
228 struct simple_pid_list
**p
;
230 for (p
= listp
; *p
!= NULL
; p
= &(*p
)->next
)
231 if ((*p
)->pid
== pid
)
233 struct simple_pid_list
*next
= (*p
)->next
;
235 *statusp
= (*p
)->status
;
243 enum stopping_threads_kind
245 /* Not stopping threads presently. */
246 NOT_STOPPING_THREADS
,
248 /* Stopping threads. */
251 /* Stopping and suspending threads. */
252 STOPPING_AND_SUSPENDING_THREADS
255 /* This is set while stop_all_lwps is in effect. */
256 enum stopping_threads_kind stopping_threads
= NOT_STOPPING_THREADS
;
258 /* FIXME make into a target method? */
259 int using_threads
= 1;
261 /* True if we're presently stabilizing threads (moving them out of
263 static int stabilizing_threads
;
265 static void unsuspend_all_lwps (struct lwp_info
*except
);
266 static void mark_lwp_dead (struct lwp_info
*lwp
, int wstat
);
267 static int lwp_is_marked_dead (struct lwp_info
*lwp
);
268 static int kill_lwp (unsigned long lwpid
, int signo
);
269 static void enqueue_pending_signal (struct lwp_info
*lwp
, int signal
, siginfo_t
*info
);
270 static int linux_low_ptrace_options (int attached
);
271 static int check_ptrace_stopped_lwp_gone (struct lwp_info
*lp
);
273 /* When the event-loop is doing a step-over, this points at the thread
275 ptid_t step_over_bkpt
;
278 linux_process_target::low_supports_breakpoints ()
284 linux_process_target::low_get_pc (regcache
*regcache
)
290 linux_process_target::low_set_pc (regcache
*regcache
, CORE_ADDR newpc
)
292 gdb_assert_not_reached ("linux target op low_set_pc is not implemented");
295 std::vector
<CORE_ADDR
>
296 linux_process_target::low_get_next_pcs (regcache
*regcache
)
298 gdb_assert_not_reached ("linux target op low_get_next_pcs is not "
303 linux_process_target::low_decr_pc_after_break ()
308 /* True if LWP is stopped in its stepping range. */
311 lwp_in_step_range (struct lwp_info
*lwp
)
313 CORE_ADDR pc
= lwp
->stop_pc
;
315 return (pc
>= lwp
->step_range_start
&& pc
< lwp
->step_range_end
);
318 /* The read/write ends of the pipe registered as waitable file in the
320 static int linux_event_pipe
[2] = { -1, -1 };
322 /* True if we're currently in async mode. */
323 #define target_is_async_p() (linux_event_pipe[0] != -1)
325 static void send_sigstop (struct lwp_info
*lwp
);
327 /* Return non-zero if HEADER is a 64-bit ELF file. */
330 elf_64_header_p (const Elf64_Ehdr
*header
, unsigned int *machine
)
332 if (header
->e_ident
[EI_MAG0
] == ELFMAG0
333 && header
->e_ident
[EI_MAG1
] == ELFMAG1
334 && header
->e_ident
[EI_MAG2
] == ELFMAG2
335 && header
->e_ident
[EI_MAG3
] == ELFMAG3
)
337 *machine
= header
->e_machine
;
338 return header
->e_ident
[EI_CLASS
] == ELFCLASS64
;
345 /* Return non-zero if FILE is a 64-bit ELF file,
346 zero if the file is not a 64-bit ELF file,
347 and -1 if the file is not accessible or doesn't exist. */
350 elf_64_file_p (const char *file
, unsigned int *machine
)
355 fd
= open (file
, O_RDONLY
);
359 if (read (fd
, &header
, sizeof (header
)) != sizeof (header
))
366 return elf_64_header_p (&header
, machine
);
369 /* Accepts an integer PID; Returns true if the executable PID is
370 running is a 64-bit ELF file.. */
373 linux_pid_exe_is_elf_64_file (int pid
, unsigned int *machine
)
377 sprintf (file
, "/proc/%d/exe", pid
);
378 return elf_64_file_p (file
, machine
);
382 linux_process_target::delete_lwp (lwp_info
*lwp
)
384 struct thread_info
*thr
= get_lwp_thread (lwp
);
387 debug_printf ("deleting %ld\n", lwpid_of (thr
));
391 low_delete_thread (lwp
->arch_private
);
397 linux_process_target::low_delete_thread (arch_lwp_info
*info
)
399 /* Default implementation should be overridden if architecture-specific
400 info is being used. */
401 gdb_assert (info
== nullptr);
405 linux_process_target::add_linux_process (int pid
, int attached
)
407 struct process_info
*proc
;
409 proc
= add_process (pid
, attached
);
410 proc
->priv
= XCNEW (struct process_info_private
);
412 proc
->priv
->arch_private
= low_new_process ();
418 linux_process_target::low_new_process ()
424 linux_process_target::low_delete_process (arch_process_info
*info
)
426 /* Default implementation must be overridden if architecture-specific
428 gdb_assert (info
== nullptr);
432 linux_process_target::low_new_fork (process_info
*parent
, process_info
*child
)
438 linux_process_target::arch_setup_thread (thread_info
*thread
)
440 struct thread_info
*saved_thread
;
442 saved_thread
= current_thread
;
443 current_thread
= thread
;
447 current_thread
= saved_thread
;
451 linux_process_target::handle_extended_wait (lwp_info
**orig_event_lwp
,
454 client_state
&cs
= get_client_state ();
455 struct lwp_info
*event_lwp
= *orig_event_lwp
;
456 int event
= linux_ptrace_get_extended_event (wstat
);
457 struct thread_info
*event_thr
= get_lwp_thread (event_lwp
);
458 struct lwp_info
*new_lwp
;
460 gdb_assert (event_lwp
->waitstatus
.kind
== TARGET_WAITKIND_IGNORE
);
462 /* All extended events we currently use are mid-syscall. Only
463 PTRACE_EVENT_STOP is delivered more like a signal-stop, but
464 you have to be using PTRACE_SEIZE to get that. */
465 event_lwp
->syscall_state
= TARGET_WAITKIND_SYSCALL_ENTRY
;
467 if ((event
== PTRACE_EVENT_FORK
) || (event
== PTRACE_EVENT_VFORK
)
468 || (event
== PTRACE_EVENT_CLONE
))
471 unsigned long new_pid
;
474 /* Get the pid of the new lwp. */
475 ptrace (PTRACE_GETEVENTMSG
, lwpid_of (event_thr
), (PTRACE_TYPE_ARG3
) 0,
478 /* If we haven't already seen the new PID stop, wait for it now. */
479 if (!pull_pid_from_list (&stopped_pids
, new_pid
, &status
))
481 /* The new child has a pending SIGSTOP. We can't affect it until it
482 hits the SIGSTOP, but we're already attached. */
484 ret
= my_waitpid (new_pid
, &status
, __WALL
);
487 perror_with_name ("waiting for new child");
488 else if (ret
!= new_pid
)
489 warning ("wait returned unexpected PID %d", ret
);
490 else if (!WIFSTOPPED (status
))
491 warning ("wait returned unexpected status 0x%x", status
);
494 if (event
== PTRACE_EVENT_FORK
|| event
== PTRACE_EVENT_VFORK
)
496 struct process_info
*parent_proc
;
497 struct process_info
*child_proc
;
498 struct lwp_info
*child_lwp
;
499 struct thread_info
*child_thr
;
500 struct target_desc
*tdesc
;
502 ptid
= ptid_t (new_pid
, new_pid
, 0);
506 debug_printf ("HEW: Got fork event from LWP %ld, "
508 ptid_of (event_thr
).lwp (),
512 /* Add the new process to the tables and clone the breakpoint
513 lists of the parent. We need to do this even if the new process
514 will be detached, since we will need the process object and the
515 breakpoints to remove any breakpoints from memory when we
516 detach, and the client side will access registers. */
517 child_proc
= add_linux_process (new_pid
, 0);
518 gdb_assert (child_proc
!= NULL
);
519 child_lwp
= add_lwp (ptid
);
520 gdb_assert (child_lwp
!= NULL
);
521 child_lwp
->stopped
= 1;
522 child_lwp
->must_set_ptrace_flags
= 1;
523 child_lwp
->status_pending_p
= 0;
524 child_thr
= get_lwp_thread (child_lwp
);
525 child_thr
->last_resume_kind
= resume_stop
;
526 child_thr
->last_status
.kind
= TARGET_WAITKIND_STOPPED
;
528 /* If we're suspending all threads, leave this one suspended
529 too. If the fork/clone parent is stepping over a breakpoint,
530 all other threads have been suspended already. Leave the
531 child suspended too. */
532 if (stopping_threads
== STOPPING_AND_SUSPENDING_THREADS
533 || event_lwp
->bp_reinsert
!= 0)
536 debug_printf ("HEW: leaving child suspended\n");
537 child_lwp
->suspended
= 1;
540 parent_proc
= get_thread_process (event_thr
);
541 child_proc
->attached
= parent_proc
->attached
;
543 if (event_lwp
->bp_reinsert
!= 0
544 && supports_software_single_step ()
545 && event
== PTRACE_EVENT_VFORK
)
547 /* If we leave single-step breakpoints there, child will
548 hit it, so uninsert single-step breakpoints from parent
549 (and child). Once vfork child is done, reinsert
550 them back to parent. */
551 uninsert_single_step_breakpoints (event_thr
);
554 clone_all_breakpoints (child_thr
, event_thr
);
556 tdesc
= allocate_target_description ();
557 copy_target_description (tdesc
, parent_proc
->tdesc
);
558 child_proc
->tdesc
= tdesc
;
560 /* Clone arch-specific process data. */
561 low_new_fork (parent_proc
, child_proc
);
563 /* Save fork info in the parent thread. */
564 if (event
== PTRACE_EVENT_FORK
)
565 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_FORKED
;
566 else if (event
== PTRACE_EVENT_VFORK
)
567 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_VFORKED
;
569 event_lwp
->waitstatus
.value
.related_pid
= ptid
;
571 /* The status_pending field contains bits denoting the
572 extended event, so when the pending event is handled,
573 the handler will look at lwp->waitstatus. */
574 event_lwp
->status_pending_p
= 1;
575 event_lwp
->status_pending
= wstat
;
577 /* Link the threads until the parent event is passed on to
579 event_lwp
->fork_relative
= child_lwp
;
580 child_lwp
->fork_relative
= event_lwp
;
582 /* If the parent thread is doing step-over with single-step
583 breakpoints, the list of single-step breakpoints are cloned
584 from the parent's. Remove them from the child process.
585 In case of vfork, we'll reinsert them back once vforked
587 if (event_lwp
->bp_reinsert
!= 0
588 && supports_software_single_step ())
590 /* The child process is forked and stopped, so it is safe
591 to access its memory without stopping all other threads
592 from other processes. */
593 delete_single_step_breakpoints (child_thr
);
595 gdb_assert (has_single_step_breakpoints (event_thr
));
596 gdb_assert (!has_single_step_breakpoints (child_thr
));
599 /* Report the event. */
604 debug_printf ("HEW: Got clone event "
605 "from LWP %ld, new child is LWP %ld\n",
606 lwpid_of (event_thr
), new_pid
);
608 ptid
= ptid_t (pid_of (event_thr
), new_pid
, 0);
609 new_lwp
= add_lwp (ptid
);
611 /* Either we're going to immediately resume the new thread
612 or leave it stopped. resume_one_lwp is a nop if it
613 thinks the thread is currently running, so set this first
614 before calling resume_one_lwp. */
615 new_lwp
->stopped
= 1;
617 /* If we're suspending all threads, leave this one suspended
618 too. If the fork/clone parent is stepping over a breakpoint,
619 all other threads have been suspended already. Leave the
620 child suspended too. */
621 if (stopping_threads
== STOPPING_AND_SUSPENDING_THREADS
622 || event_lwp
->bp_reinsert
!= 0)
623 new_lwp
->suspended
= 1;
625 /* Normally we will get the pending SIGSTOP. But in some cases
626 we might get another signal delivered to the group first.
627 If we do get another signal, be sure not to lose it. */
628 if (WSTOPSIG (status
) != SIGSTOP
)
630 new_lwp
->stop_expected
= 1;
631 new_lwp
->status_pending_p
= 1;
632 new_lwp
->status_pending
= status
;
634 else if (cs
.report_thread_events
)
636 new_lwp
->waitstatus
.kind
= TARGET_WAITKIND_THREAD_CREATED
;
637 new_lwp
->status_pending_p
= 1;
638 new_lwp
->status_pending
= status
;
642 thread_db_notice_clone (event_thr
, ptid
);
645 /* Don't report the event. */
648 else if (event
== PTRACE_EVENT_VFORK_DONE
)
650 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_VFORK_DONE
;
652 if (event_lwp
->bp_reinsert
!= 0 && supports_software_single_step ())
654 reinsert_single_step_breakpoints (event_thr
);
656 gdb_assert (has_single_step_breakpoints (event_thr
));
659 /* Report the event. */
662 else if (event
== PTRACE_EVENT_EXEC
&& cs
.report_exec_events
)
664 struct process_info
*proc
;
665 std::vector
<int> syscalls_to_catch
;
671 debug_printf ("HEW: Got exec event from LWP %ld\n",
672 lwpid_of (event_thr
));
675 /* Get the event ptid. */
676 event_ptid
= ptid_of (event_thr
);
677 event_pid
= event_ptid
.pid ();
679 /* Save the syscall list from the execing process. */
680 proc
= get_thread_process (event_thr
);
681 syscalls_to_catch
= std::move (proc
->syscalls_to_catch
);
683 /* Delete the execing process and all its threads. */
685 current_thread
= NULL
;
687 /* Create a new process/lwp/thread. */
688 proc
= add_linux_process (event_pid
, 0);
689 event_lwp
= add_lwp (event_ptid
);
690 event_thr
= get_lwp_thread (event_lwp
);
691 gdb_assert (current_thread
== event_thr
);
692 arch_setup_thread (event_thr
);
694 /* Set the event status. */
695 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_EXECD
;
696 event_lwp
->waitstatus
.value
.execd_pathname
697 = xstrdup (linux_proc_pid_to_exec_file (lwpid_of (event_thr
)));
699 /* Mark the exec status as pending. */
700 event_lwp
->stopped
= 1;
701 event_lwp
->status_pending_p
= 1;
702 event_lwp
->status_pending
= wstat
;
703 event_thr
->last_resume_kind
= resume_continue
;
704 event_thr
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
706 /* Update syscall state in the new lwp, effectively mid-syscall too. */
707 event_lwp
->syscall_state
= TARGET_WAITKIND_SYSCALL_ENTRY
;
709 /* Restore the list to catch. Don't rely on the client, which is free
710 to avoid sending a new list when the architecture doesn't change.
711 Also, for ANY_SYSCALL, the architecture doesn't really matter. */
712 proc
->syscalls_to_catch
= std::move (syscalls_to_catch
);
714 /* Report the event. */
715 *orig_event_lwp
= event_lwp
;
719 internal_error (__FILE__
, __LINE__
, _("unknown ptrace event %d"), event
);
723 linux_process_target::get_pc (lwp_info
*lwp
)
725 struct thread_info
*saved_thread
;
726 struct regcache
*regcache
;
729 if (!low_supports_breakpoints ())
732 saved_thread
= current_thread
;
733 current_thread
= get_lwp_thread (lwp
);
735 regcache
= get_thread_regcache (current_thread
, 1);
736 pc
= low_get_pc (regcache
);
739 debug_printf ("pc is 0x%lx\n", (long) pc
);
741 current_thread
= saved_thread
;
746 linux_process_target::get_syscall_trapinfo (lwp_info
*lwp
, int *sysno
)
748 struct thread_info
*saved_thread
;
749 struct regcache
*regcache
;
751 saved_thread
= current_thread
;
752 current_thread
= get_lwp_thread (lwp
);
754 regcache
= get_thread_regcache (current_thread
, 1);
755 low_get_syscall_trapinfo (regcache
, sysno
);
758 debug_printf ("get_syscall_trapinfo sysno %d\n", *sysno
);
760 current_thread
= saved_thread
;
764 linux_process_target::low_get_syscall_trapinfo (regcache
*regcache
, int *sysno
)
766 /* By default, report an unknown system call number. */
767 *sysno
= UNKNOWN_SYSCALL
;
771 linux_process_target::save_stop_reason (lwp_info
*lwp
)
774 CORE_ADDR sw_breakpoint_pc
;
775 struct thread_info
*saved_thread
;
776 #if USE_SIGTRAP_SIGINFO
780 if (!low_supports_breakpoints ())
784 sw_breakpoint_pc
= pc
- low_decr_pc_after_break ();
786 /* breakpoint_at reads from the current thread. */
787 saved_thread
= current_thread
;
788 current_thread
= get_lwp_thread (lwp
);
790 #if USE_SIGTRAP_SIGINFO
791 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
792 (PTRACE_TYPE_ARG3
) 0, &siginfo
) == 0)
794 if (siginfo
.si_signo
== SIGTRAP
)
796 if (GDB_ARCH_IS_TRAP_BRKPT (siginfo
.si_code
)
797 && GDB_ARCH_IS_TRAP_HWBKPT (siginfo
.si_code
))
799 /* The si_code is ambiguous on this arch -- check debug
801 if (!check_stopped_by_watchpoint (lwp
))
802 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
804 else if (GDB_ARCH_IS_TRAP_BRKPT (siginfo
.si_code
))
806 /* If we determine the LWP stopped for a SW breakpoint,
807 trust it. Particularly don't check watchpoint
808 registers, because at least on s390, we'd find
809 stopped-by-watchpoint as long as there's a watchpoint
811 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
813 else if (GDB_ARCH_IS_TRAP_HWBKPT (siginfo
.si_code
))
815 /* This can indicate either a hardware breakpoint or
816 hardware watchpoint. Check debug registers. */
817 if (!check_stopped_by_watchpoint (lwp
))
818 lwp
->stop_reason
= TARGET_STOPPED_BY_HW_BREAKPOINT
;
820 else if (siginfo
.si_code
== TRAP_TRACE
)
822 /* We may have single stepped an instruction that
823 triggered a watchpoint. In that case, on some
824 architectures (such as x86), instead of TRAP_HWBKPT,
825 si_code indicates TRAP_TRACE, and we need to check
826 the debug registers separately. */
827 if (!check_stopped_by_watchpoint (lwp
))
828 lwp
->stop_reason
= TARGET_STOPPED_BY_SINGLE_STEP
;
833 /* We may have just stepped a breakpoint instruction. E.g., in
834 non-stop mode, GDB first tells the thread A to step a range, and
835 then the user inserts a breakpoint inside the range. In that
836 case we need to report the breakpoint PC. */
837 if ((!lwp
->stepping
|| lwp
->stop_pc
== sw_breakpoint_pc
)
838 && low_breakpoint_at (sw_breakpoint_pc
))
839 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
841 if (hardware_breakpoint_inserted_here (pc
))
842 lwp
->stop_reason
= TARGET_STOPPED_BY_HW_BREAKPOINT
;
844 if (lwp
->stop_reason
== TARGET_STOPPED_BY_NO_REASON
)
845 check_stopped_by_watchpoint (lwp
);
848 if (lwp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
)
852 struct thread_info
*thr
= get_lwp_thread (lwp
);
854 debug_printf ("CSBB: %s stopped by software breakpoint\n",
855 target_pid_to_str (ptid_of (thr
)));
858 /* Back up the PC if necessary. */
859 if (pc
!= sw_breakpoint_pc
)
861 struct regcache
*regcache
862 = get_thread_regcache (current_thread
, 1);
863 low_set_pc (regcache
, sw_breakpoint_pc
);
866 /* Update this so we record the correct stop PC below. */
867 pc
= sw_breakpoint_pc
;
869 else if (lwp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
)
873 struct thread_info
*thr
= get_lwp_thread (lwp
);
875 debug_printf ("CSBB: %s stopped by hardware breakpoint\n",
876 target_pid_to_str (ptid_of (thr
)));
879 else if (lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
)
883 struct thread_info
*thr
= get_lwp_thread (lwp
);
885 debug_printf ("CSBB: %s stopped by hardware watchpoint\n",
886 target_pid_to_str (ptid_of (thr
)));
889 else if (lwp
->stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
)
893 struct thread_info
*thr
= get_lwp_thread (lwp
);
895 debug_printf ("CSBB: %s stopped by trace\n",
896 target_pid_to_str (ptid_of (thr
)));
901 current_thread
= saved_thread
;
906 linux_process_target::add_lwp (ptid_t ptid
)
908 struct lwp_info
*lwp
;
910 lwp
= new lwp_info
{};
912 lwp
->waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
914 lwp
->thread
= add_thread (ptid
, lwp
);
916 low_new_thread (lwp
);
922 linux_process_target::low_new_thread (lwp_info
*info
)
927 /* Callback to be used when calling fork_inferior, responsible for
928 actually initiating the tracing of the inferior. */
933 if (ptrace (PTRACE_TRACEME
, 0, (PTRACE_TYPE_ARG3
) 0,
934 (PTRACE_TYPE_ARG4
) 0) < 0)
935 trace_start_error_with_name ("ptrace");
937 if (setpgid (0, 0) < 0)
938 trace_start_error_with_name ("setpgid");
940 /* If GDBserver is connected to gdb via stdio, redirect the inferior's
941 stdout to stderr so that inferior i/o doesn't corrupt the connection.
942 Also, redirect stdin to /dev/null. */
943 if (remote_connection_is_stdio ())
946 trace_start_error_with_name ("close");
947 if (open ("/dev/null", O_RDONLY
) < 0)
948 trace_start_error_with_name ("open");
950 trace_start_error_with_name ("dup2");
951 if (write (2, "stdin/stdout redirected\n",
952 sizeof ("stdin/stdout redirected\n") - 1) < 0)
954 /* Errors ignored. */;
959 /* Start an inferior process and returns its pid.
960 PROGRAM is the name of the program to be started, and PROGRAM_ARGS
961 are its arguments. */
964 linux_process_target::create_inferior (const char *program
,
965 const std::vector
<char *> &program_args
)
967 client_state
&cs
= get_client_state ();
968 struct lwp_info
*new_lwp
;
973 maybe_disable_address_space_randomization restore_personality
974 (cs
.disable_randomization
);
975 std::string str_program_args
= construct_inferior_arguments (program_args
);
977 pid
= fork_inferior (program
,
978 str_program_args
.c_str (),
979 get_environ ()->envp (), linux_ptrace_fun
,
980 NULL
, NULL
, NULL
, NULL
);
983 add_linux_process (pid
, 0);
985 ptid
= ptid_t (pid
, pid
, 0);
986 new_lwp
= add_lwp (ptid
);
987 new_lwp
->must_set_ptrace_flags
= 1;
989 post_fork_inferior (pid
, program
);
994 /* Implement the post_create_inferior target_ops method. */
997 linux_process_target::post_create_inferior ()
999 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
1003 if (lwp
->must_set_ptrace_flags
)
1005 struct process_info
*proc
= current_process ();
1006 int options
= linux_low_ptrace_options (proc
->attached
);
1008 linux_enable_event_reporting (lwpid_of (current_thread
), options
);
1009 lwp
->must_set_ptrace_flags
= 0;
1014 linux_process_target::attach_lwp (ptid_t ptid
)
1016 struct lwp_info
*new_lwp
;
1017 int lwpid
= ptid
.lwp ();
1019 if (ptrace (PTRACE_ATTACH
, lwpid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0)
1023 new_lwp
= add_lwp (ptid
);
1025 /* We need to wait for SIGSTOP before being able to make the next
1026 ptrace call on this LWP. */
1027 new_lwp
->must_set_ptrace_flags
= 1;
1029 if (linux_proc_pid_is_stopped (lwpid
))
1032 debug_printf ("Attached to a stopped process\n");
1034 /* The process is definitely stopped. It is in a job control
1035 stop, unless the kernel predates the TASK_STOPPED /
1036 TASK_TRACED distinction, in which case it might be in a
1037 ptrace stop. Make sure it is in a ptrace stop; from there we
1038 can kill it, signal it, et cetera.
1040 First make sure there is a pending SIGSTOP. Since we are
1041 already attached, the process can not transition from stopped
1042 to running without a PTRACE_CONT; so we know this signal will
1043 go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
1044 probably already in the queue (unless this kernel is old
1045 enough to use TASK_STOPPED for ptrace stops); but since
1046 SIGSTOP is not an RT signal, it can only be queued once. */
1047 kill_lwp (lwpid
, SIGSTOP
);
1049 /* Finally, resume the stopped process. This will deliver the
1050 SIGSTOP (or a higher priority signal, just like normal
1051 PTRACE_ATTACH), which we'll catch later on. */
1052 ptrace (PTRACE_CONT
, lwpid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
1055 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
1056 brings it to a halt.
1058 There are several cases to consider here:
1060 1) gdbserver has already attached to the process and is being notified
1061 of a new thread that is being created.
1062 In this case we should ignore that SIGSTOP and resume the
1063 process. This is handled below by setting stop_expected = 1,
1064 and the fact that add_thread sets last_resume_kind ==
1067 2) This is the first thread (the process thread), and we're attaching
1068 to it via attach_inferior.
1069 In this case we want the process thread to stop.
1070 This is handled by having linux_attach set last_resume_kind ==
1071 resume_stop after we return.
1073 If the pid we are attaching to is also the tgid, we attach to and
1074 stop all the existing threads. Otherwise, we attach to pid and
1075 ignore any other threads in the same group as this pid.
1077 3) GDB is connecting to gdbserver and is requesting an enumeration of all
1079 In this case we want the thread to stop.
1080 FIXME: This case is currently not properly handled.
1081 We should wait for the SIGSTOP but don't. Things work apparently
1082 because enough time passes between when we ptrace (ATTACH) and when
1083 gdb makes the next ptrace call on the thread.
1085 On the other hand, if we are currently trying to stop all threads, we
1086 should treat the new thread as if we had sent it a SIGSTOP. This works
1087 because we are guaranteed that the add_lwp call above added us to the
1088 end of the list, and so the new thread has not yet reached
1089 wait_for_sigstop (but will). */
1090 new_lwp
->stop_expected
= 1;
1095 /* Callback for linux_proc_attach_tgid_threads. Attach to PTID if not
1096 already attached. Returns true if a new LWP is found, false
1100 attach_proc_task_lwp_callback (ptid_t ptid
)
1102 /* Is this a new thread? */
1103 if (find_thread_ptid (ptid
) == NULL
)
1105 int lwpid
= ptid
.lwp ();
1109 debug_printf ("Found new lwp %d\n", lwpid
);
1111 err
= the_linux_target
->attach_lwp (ptid
);
1113 /* Be quiet if we simply raced with the thread exiting. EPERM
1114 is returned if the thread's task still exists, and is marked
1115 as exited or zombie, as well as other conditions, so in that
1116 case, confirm the status in /proc/PID/status. */
1118 || (err
== EPERM
&& linux_proc_pid_is_gone (lwpid
)))
1122 debug_printf ("Cannot attach to lwp %d: "
1123 "thread is gone (%d: %s)\n",
1124 lwpid
, err
, safe_strerror (err
));
1130 = linux_ptrace_attach_fail_reason_string (ptid
, err
);
1132 warning (_("Cannot attach to lwp %d: %s"), lwpid
, reason
.c_str ());
1140 static void async_file_mark (void);
1142 /* Attach to PID. If PID is the tgid, attach to it and all
1146 linux_process_target::attach (unsigned long pid
)
1148 struct process_info
*proc
;
1149 struct thread_info
*initial_thread
;
1150 ptid_t ptid
= ptid_t (pid
, pid
, 0);
1153 proc
= add_linux_process (pid
, 1);
1155 /* Attach to PID. We will check for other threads
1157 err
= attach_lwp (ptid
);
1160 remove_process (proc
);
1162 std::string reason
= linux_ptrace_attach_fail_reason_string (ptid
, err
);
1163 error ("Cannot attach to process %ld: %s", pid
, reason
.c_str ());
1166 /* Don't ignore the initial SIGSTOP if we just attached to this
1167 process. It will be collected by wait shortly. */
1168 initial_thread
= find_thread_ptid (ptid_t (pid
, pid
, 0));
1169 initial_thread
->last_resume_kind
= resume_stop
;
1171 /* We must attach to every LWP. If /proc is mounted, use that to
1172 find them now. On the one hand, the inferior may be using raw
1173 clone instead of using pthreads. On the other hand, even if it
1174 is using pthreads, GDB may not be connected yet (thread_db needs
1175 to do symbol lookups, through qSymbol). Also, thread_db walks
1176 structures in the inferior's address space to find the list of
1177 threads/LWPs, and those structures may well be corrupted. Note
1178 that once thread_db is loaded, we'll still use it to list threads
1179 and associate pthread info with each LWP. */
1180 linux_proc_attach_tgid_threads (pid
, attach_proc_task_lwp_callback
);
1182 /* GDB will shortly read the xml target description for this
1183 process, to figure out the process' architecture. But the target
1184 description is only filled in when the first process/thread in
1185 the thread group reports its initial PTRACE_ATTACH SIGSTOP. Do
1186 that now, otherwise, if GDB is fast enough, it could read the
1187 target description _before_ that initial stop. */
1190 struct lwp_info
*lwp
;
1192 ptid_t pid_ptid
= ptid_t (pid
);
1194 lwpid
= wait_for_event_filtered (pid_ptid
, pid_ptid
, &wstat
, __WALL
);
1195 gdb_assert (lwpid
> 0);
1197 lwp
= find_lwp_pid (ptid_t (lwpid
));
1199 if (!WIFSTOPPED (wstat
) || WSTOPSIG (wstat
) != SIGSTOP
)
1201 lwp
->status_pending_p
= 1;
1202 lwp
->status_pending
= wstat
;
1205 initial_thread
->last_resume_kind
= resume_continue
;
1209 gdb_assert (proc
->tdesc
!= NULL
);
1216 last_thread_of_process_p (int pid
)
1218 bool seen_one
= false;
1220 thread_info
*thread
= find_thread (pid
, [&] (thread_info
*thr_arg
)
1224 /* This is the first thread of this process we see. */
1230 /* This is the second thread of this process we see. */
1235 return thread
== NULL
;
1241 linux_kill_one_lwp (struct lwp_info
*lwp
)
1243 struct thread_info
*thr
= get_lwp_thread (lwp
);
1244 int pid
= lwpid_of (thr
);
1246 /* PTRACE_KILL is unreliable. After stepping into a signal handler,
1247 there is no signal context, and ptrace(PTRACE_KILL) (or
1248 ptrace(PTRACE_CONT, SIGKILL), pretty much the same) acts like
1249 ptrace(CONT, pid, 0,0) and just resumes the tracee. A better
1250 alternative is to kill with SIGKILL. We only need one SIGKILL
1251 per process, not one for each thread. But since we still support
1252 support debugging programs using raw clone without CLONE_THREAD,
1253 we send one for each thread. For years, we used PTRACE_KILL
1254 only, so we're being a bit paranoid about some old kernels where
1255 PTRACE_KILL might work better (dubious if there are any such, but
1256 that's why it's paranoia), so we try SIGKILL first, PTRACE_KILL
1257 second, and so we're fine everywhere. */
1260 kill_lwp (pid
, SIGKILL
);
1263 int save_errno
= errno
;
1265 debug_printf ("LKL: kill_lwp (SIGKILL) %s, 0, 0 (%s)\n",
1266 target_pid_to_str (ptid_of (thr
)),
1267 save_errno
? safe_strerror (save_errno
) : "OK");
1271 ptrace (PTRACE_KILL
, pid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
1274 int save_errno
= errno
;
1276 debug_printf ("LKL: PTRACE_KILL %s, 0, 0 (%s)\n",
1277 target_pid_to_str (ptid_of (thr
)),
1278 save_errno
? safe_strerror (save_errno
) : "OK");
1282 /* Kill LWP and wait for it to die. */
1285 kill_wait_lwp (struct lwp_info
*lwp
)
1287 struct thread_info
*thr
= get_lwp_thread (lwp
);
1288 int pid
= ptid_of (thr
).pid ();
1289 int lwpid
= ptid_of (thr
).lwp ();
1294 debug_printf ("kwl: killing lwp %d, for pid: %d\n", lwpid
, pid
);
1298 linux_kill_one_lwp (lwp
);
1300 /* Make sure it died. Notes:
1302 - The loop is most likely unnecessary.
1304 - We don't use wait_for_event as that could delete lwps
1305 while we're iterating over them. We're not interested in
1306 any pending status at this point, only in making sure all
1307 wait status on the kernel side are collected until the
1310 - We don't use __WALL here as the __WALL emulation relies on
1311 SIGCHLD, and killing a stopped process doesn't generate
1312 one, nor an exit status.
1314 res
= my_waitpid (lwpid
, &wstat
, 0);
1315 if (res
== -1 && errno
== ECHILD
)
1316 res
= my_waitpid (lwpid
, &wstat
, __WCLONE
);
1317 } while (res
> 0 && WIFSTOPPED (wstat
));
1319 /* Even if it was stopped, the child may have already disappeared.
1320 E.g., if it was killed by SIGKILL. */
1321 if (res
< 0 && errno
!= ECHILD
)
1322 perror_with_name ("kill_wait_lwp");
1325 /* Callback for `for_each_thread'. Kills an lwp of a given process,
1326 except the leader. */
1329 kill_one_lwp_callback (thread_info
*thread
, int pid
)
1331 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1333 /* We avoid killing the first thread here, because of a Linux kernel (at
1334 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
1335 the children get a chance to be reaped, it will remain a zombie
1338 if (lwpid_of (thread
) == pid
)
1341 debug_printf ("lkop: is last of process %s\n",
1342 target_pid_to_str (thread
->id
));
1346 kill_wait_lwp (lwp
);
1350 linux_process_target::kill (process_info
*process
)
1352 int pid
= process
->pid
;
1354 /* If we're killing a running inferior, make sure it is stopped
1355 first, as PTRACE_KILL will not work otherwise. */
1356 stop_all_lwps (0, NULL
);
1358 for_each_thread (pid
, [&] (thread_info
*thread
)
1360 kill_one_lwp_callback (thread
, pid
);
1363 /* See the comment in linux_kill_one_lwp. We did not kill the first
1364 thread in the list, so do so now. */
1365 lwp_info
*lwp
= find_lwp_pid (ptid_t (pid
));
1370 debug_printf ("lk_1: cannot find lwp for pid: %d\n",
1374 kill_wait_lwp (lwp
);
1378 /* Since we presently can only stop all lwps of all processes, we
1379 need to unstop lwps of other processes. */
1380 unstop_all_lwps (0, NULL
);
1384 /* Get pending signal of THREAD, for detaching purposes. This is the
1385 signal the thread last stopped for, which we need to deliver to the
1386 thread when detaching, otherwise, it'd be suppressed/lost. */
1389 get_detach_signal (struct thread_info
*thread
)
1391 client_state
&cs
= get_client_state ();
1392 enum gdb_signal signo
= GDB_SIGNAL_0
;
1394 struct lwp_info
*lp
= get_thread_lwp (thread
);
1396 if (lp
->status_pending_p
)
1397 status
= lp
->status_pending
;
1400 /* If the thread had been suspended by gdbserver, and it stopped
1401 cleanly, then it'll have stopped with SIGSTOP. But we don't
1402 want to deliver that SIGSTOP. */
1403 if (thread
->last_status
.kind
!= TARGET_WAITKIND_STOPPED
1404 || thread
->last_status
.value
.sig
== GDB_SIGNAL_0
)
1407 /* Otherwise, we may need to deliver the signal we
1409 status
= lp
->last_status
;
1412 if (!WIFSTOPPED (status
))
1415 debug_printf ("GPS: lwp %s hasn't stopped: no pending signal\n",
1416 target_pid_to_str (ptid_of (thread
)));
1420 /* Extended wait statuses aren't real SIGTRAPs. */
1421 if (WSTOPSIG (status
) == SIGTRAP
&& linux_is_extended_waitstatus (status
))
1424 debug_printf ("GPS: lwp %s had stopped with extended "
1425 "status: no pending signal\n",
1426 target_pid_to_str (ptid_of (thread
)));
1430 signo
= gdb_signal_from_host (WSTOPSIG (status
));
1432 if (cs
.program_signals_p
&& !cs
.program_signals
[signo
])
1435 debug_printf ("GPS: lwp %s had signal %s, but it is in nopass state\n",
1436 target_pid_to_str (ptid_of (thread
)),
1437 gdb_signal_to_string (signo
));
1440 else if (!cs
.program_signals_p
1441 /* If we have no way to know which signals GDB does not
1442 want to have passed to the program, assume
1443 SIGTRAP/SIGINT, which is GDB's default. */
1444 && (signo
== GDB_SIGNAL_TRAP
|| signo
== GDB_SIGNAL_INT
))
1447 debug_printf ("GPS: lwp %s had signal %s, "
1448 "but we don't know if we should pass it. "
1449 "Default to not.\n",
1450 target_pid_to_str (ptid_of (thread
)),
1451 gdb_signal_to_string (signo
));
1457 debug_printf ("GPS: lwp %s has pending signal %s: delivering it.\n",
1458 target_pid_to_str (ptid_of (thread
)),
1459 gdb_signal_to_string (signo
));
1461 return WSTOPSIG (status
);
1466 linux_process_target::detach_one_lwp (lwp_info
*lwp
)
1468 struct thread_info
*thread
= get_lwp_thread (lwp
);
1472 /* If there is a pending SIGSTOP, get rid of it. */
1473 if (lwp
->stop_expected
)
1476 debug_printf ("Sending SIGCONT to %s\n",
1477 target_pid_to_str (ptid_of (thread
)));
1479 kill_lwp (lwpid_of (thread
), SIGCONT
);
1480 lwp
->stop_expected
= 0;
1483 /* Pass on any pending signal for this thread. */
1484 sig
= get_detach_signal (thread
);
1486 /* Preparing to resume may try to write registers, and fail if the
1487 lwp is zombie. If that happens, ignore the error. We'll handle
1488 it below, when detach fails with ESRCH. */
1491 /* Flush any pending changes to the process's registers. */
1492 regcache_invalidate_thread (thread
);
1494 /* Finally, let it resume. */
1495 low_prepare_to_resume (lwp
);
1497 catch (const gdb_exception_error
&ex
)
1499 if (!check_ptrace_stopped_lwp_gone (lwp
))
1503 lwpid
= lwpid_of (thread
);
1504 if (ptrace (PTRACE_DETACH
, lwpid
, (PTRACE_TYPE_ARG3
) 0,
1505 (PTRACE_TYPE_ARG4
) (long) sig
) < 0)
1507 int save_errno
= errno
;
1509 /* We know the thread exists, so ESRCH must mean the lwp is
1510 zombie. This can happen if one of the already-detached
1511 threads exits the whole thread group. In that case we're
1512 still attached, and must reap the lwp. */
1513 if (save_errno
== ESRCH
)
1517 ret
= my_waitpid (lwpid
, &status
, __WALL
);
1520 warning (_("Couldn't reap LWP %d while detaching: %s"),
1521 lwpid
, safe_strerror (errno
));
1523 else if (!WIFEXITED (status
) && !WIFSIGNALED (status
))
1525 warning (_("Reaping LWP %d while detaching "
1526 "returned unexpected status 0x%x"),
1532 error (_("Can't detach %s: %s"),
1533 target_pid_to_str (ptid_of (thread
)),
1534 safe_strerror (save_errno
));
1537 else if (debug_threads
)
1539 debug_printf ("PTRACE_DETACH (%s, %s, 0) (OK)\n",
1540 target_pid_to_str (ptid_of (thread
)),
1548 linux_process_target::detach (process_info
*process
)
1550 struct lwp_info
*main_lwp
;
1552 /* As there's a step over already in progress, let it finish first,
1553 otherwise nesting a stabilize_threads operation on top gets real
1555 complete_ongoing_step_over ();
1557 /* Stop all threads before detaching. First, ptrace requires that
1558 the thread is stopped to successfully detach. Second, thread_db
1559 may need to uninstall thread event breakpoints from memory, which
1560 only works with a stopped process anyway. */
1561 stop_all_lwps (0, NULL
);
1563 #ifdef USE_THREAD_DB
1564 thread_db_detach (process
);
1567 /* Stabilize threads (move out of jump pads). */
1568 target_stabilize_threads ();
1570 /* Detach from the clone lwps first. If the thread group exits just
1571 while we're detaching, we must reap the clone lwps before we're
1572 able to reap the leader. */
1573 for_each_thread (process
->pid
, [this] (thread_info
*thread
)
1575 /* We don't actually detach from the thread group leader just yet.
1576 If the thread group exits, we must reap the zombie clone lwps
1577 before we're able to reap the leader. */
1578 if (thread
->id
.pid () == thread
->id
.lwp ())
1581 lwp_info
*lwp
= get_thread_lwp (thread
);
1582 detach_one_lwp (lwp
);
1585 main_lwp
= find_lwp_pid (ptid_t (process
->pid
));
1586 detach_one_lwp (main_lwp
);
1590 /* Since we presently can only stop all lwps of all processes, we
1591 need to unstop lwps of other processes. */
1592 unstop_all_lwps (0, NULL
);
1596 /* Remove all LWPs that belong to process PROC from the lwp list. */
1599 linux_process_target::mourn (process_info
*process
)
1601 struct process_info_private
*priv
;
1603 #ifdef USE_THREAD_DB
1604 thread_db_mourn (process
);
1607 for_each_thread (process
->pid
, [this] (thread_info
*thread
)
1609 delete_lwp (get_thread_lwp (thread
));
1612 /* Freeing all private data. */
1613 priv
= process
->priv
;
1614 low_delete_process (priv
->arch_private
);
1616 process
->priv
= NULL
;
1618 remove_process (process
);
1622 linux_process_target::join (int pid
)
1627 ret
= my_waitpid (pid
, &status
, 0);
1628 if (WIFEXITED (status
) || WIFSIGNALED (status
))
1630 } while (ret
!= -1 || errno
!= ECHILD
);
1633 /* Return true if the given thread is still alive. */
1636 linux_process_target::thread_alive (ptid_t ptid
)
1638 struct lwp_info
*lwp
= find_lwp_pid (ptid
);
1640 /* We assume we always know if a thread exits. If a whole process
1641 exited but we still haven't been able to report it to GDB, we'll
1642 hold on to the last lwp of the dead process. */
1644 return !lwp_is_marked_dead (lwp
);
1650 linux_process_target::thread_still_has_status_pending (thread_info
*thread
)
1652 struct lwp_info
*lp
= get_thread_lwp (thread
);
1654 if (!lp
->status_pending_p
)
1657 if (thread
->last_resume_kind
!= resume_stop
1658 && (lp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
1659 || lp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
1661 struct thread_info
*saved_thread
;
1665 gdb_assert (lp
->last_status
!= 0);
1669 saved_thread
= current_thread
;
1670 current_thread
= thread
;
1672 if (pc
!= lp
->stop_pc
)
1675 debug_printf ("PC of %ld changed\n",
1680 #if !USE_SIGTRAP_SIGINFO
1681 else if (lp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
1682 && !low_breakpoint_at (pc
))
1685 debug_printf ("previous SW breakpoint of %ld gone\n",
1689 else if (lp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
1690 && !hardware_breakpoint_inserted_here (pc
))
1693 debug_printf ("previous HW breakpoint of %ld gone\n",
1699 current_thread
= saved_thread
;
1704 debug_printf ("discarding pending breakpoint status\n");
1705 lp
->status_pending_p
= 0;
1713 /* Returns true if LWP is resumed from the client's perspective. */
1716 lwp_resumed (struct lwp_info
*lwp
)
1718 struct thread_info
*thread
= get_lwp_thread (lwp
);
1720 if (thread
->last_resume_kind
!= resume_stop
)
1723 /* Did gdb send us a `vCont;t', but we haven't reported the
1724 corresponding stop to gdb yet? If so, the thread is still
1725 resumed/running from gdb's perspective. */
1726 if (thread
->last_resume_kind
== resume_stop
1727 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
)
1734 linux_process_target::status_pending_p_callback (thread_info
*thread
,
1737 struct lwp_info
*lp
= get_thread_lwp (thread
);
1739 /* Check if we're only interested in events from a specific process
1740 or a specific LWP. */
1741 if (!thread
->id
.matches (ptid
))
1744 if (!lwp_resumed (lp
))
1747 if (lp
->status_pending_p
1748 && !thread_still_has_status_pending (thread
))
1750 resume_one_lwp (lp
, lp
->stepping
, GDB_SIGNAL_0
, NULL
);
1754 return lp
->status_pending_p
;
1758 find_lwp_pid (ptid_t ptid
)
1760 thread_info
*thread
= find_thread ([&] (thread_info
*thr_arg
)
1762 int lwp
= ptid
.lwp () != 0 ? ptid
.lwp () : ptid
.pid ();
1763 return thr_arg
->id
.lwp () == lwp
;
1769 return get_thread_lwp (thread
);
1772 /* Return the number of known LWPs in the tgid given by PID. */
1779 for_each_thread (pid
, [&] (thread_info
*thread
)
1787 /* See nat/linux-nat.h. */
1790 iterate_over_lwps (ptid_t filter
,
1791 gdb::function_view
<iterate_over_lwps_ftype
> callback
)
1793 thread_info
*thread
= find_thread (filter
, [&] (thread_info
*thr_arg
)
1795 lwp_info
*lwp
= get_thread_lwp (thr_arg
);
1797 return callback (lwp
);
1803 return get_thread_lwp (thread
);
1807 linux_process_target::check_zombie_leaders ()
1809 for_each_process ([this] (process_info
*proc
) {
1810 pid_t leader_pid
= pid_of (proc
);
1811 struct lwp_info
*leader_lp
;
1813 leader_lp
= find_lwp_pid (ptid_t (leader_pid
));
1816 debug_printf ("leader_pid=%d, leader_lp!=NULL=%d, "
1817 "num_lwps=%d, zombie=%d\n",
1818 leader_pid
, leader_lp
!= NULL
, num_lwps (leader_pid
),
1819 linux_proc_pid_is_zombie (leader_pid
));
1821 if (leader_lp
!= NULL
&& !leader_lp
->stopped
1822 /* Check if there are other threads in the group, as we may
1823 have raced with the inferior simply exiting. */
1824 && !last_thread_of_process_p (leader_pid
)
1825 && linux_proc_pid_is_zombie (leader_pid
))
1827 /* A leader zombie can mean one of two things:
1829 - It exited, and there's an exit status pending
1830 available, or only the leader exited (not the whole
1831 program). In the latter case, we can't waitpid the
1832 leader's exit status until all other threads are gone.
1834 - There are 3 or more threads in the group, and a thread
1835 other than the leader exec'd. On an exec, the Linux
1836 kernel destroys all other threads (except the execing
1837 one) in the thread group, and resets the execing thread's
1838 tid to the tgid. No exit notification is sent for the
1839 execing thread -- from the ptracer's perspective, it
1840 appears as though the execing thread just vanishes.
1841 Until we reap all other threads except the leader and the
1842 execing thread, the leader will be zombie, and the
1843 execing thread will be in `D (disc sleep)'. As soon as
1844 all other threads are reaped, the execing thread changes
1845 it's tid to the tgid, and the previous (zombie) leader
1846 vanishes, giving place to the "new" leader. We could try
1847 distinguishing the exit and exec cases, by waiting once
1848 more, and seeing if something comes out, but it doesn't
1849 sound useful. The previous leader _does_ go away, and
1850 we'll re-add the new one once we see the exec event
1851 (which is just the same as what would happen if the
1852 previous leader did exit voluntarily before some other
1856 debug_printf ("CZL: Thread group leader %d zombie "
1857 "(it exited, or another thread execd).\n",
1860 delete_lwp (leader_lp
);
1865 /* Callback for `find_thread'. Returns the first LWP that is not
1869 not_stopped_callback (thread_info
*thread
, ptid_t filter
)
1871 if (!thread
->id
.matches (filter
))
1874 lwp_info
*lwp
= get_thread_lwp (thread
);
1876 return !lwp
->stopped
;
1879 /* Increment LWP's suspend count. */
1882 lwp_suspended_inc (struct lwp_info
*lwp
)
1886 if (debug_threads
&& lwp
->suspended
> 4)
1888 struct thread_info
*thread
= get_lwp_thread (lwp
);
1890 debug_printf ("LWP %ld has a suspiciously high suspend count,"
1891 " suspended=%d\n", lwpid_of (thread
), lwp
->suspended
);
1895 /* Decrement LWP's suspend count. */
1898 lwp_suspended_decr (struct lwp_info
*lwp
)
1902 if (lwp
->suspended
< 0)
1904 struct thread_info
*thread
= get_lwp_thread (lwp
);
1906 internal_error (__FILE__
, __LINE__
,
1907 "unsuspend LWP %ld, suspended=%d\n", lwpid_of (thread
),
1912 /* This function should only be called if the LWP got a SIGTRAP.
1914 Handle any tracepoint steps or hits. Return true if a tracepoint
1915 event was handled, 0 otherwise. */
1918 handle_tracepoints (struct lwp_info
*lwp
)
1920 struct thread_info
*tinfo
= get_lwp_thread (lwp
);
1921 int tpoint_related_event
= 0;
1923 gdb_assert (lwp
->suspended
== 0);
1925 /* If this tracepoint hit causes a tracing stop, we'll immediately
1926 uninsert tracepoints. To do this, we temporarily pause all
1927 threads, unpatch away, and then unpause threads. We need to make
1928 sure the unpausing doesn't resume LWP too. */
1929 lwp_suspended_inc (lwp
);
1931 /* And we need to be sure that any all-threads-stopping doesn't try
1932 to move threads out of the jump pads, as it could deadlock the
1933 inferior (LWP could be in the jump pad, maybe even holding the
1936 /* Do any necessary step collect actions. */
1937 tpoint_related_event
|= tracepoint_finished_step (tinfo
, lwp
->stop_pc
);
1939 tpoint_related_event
|= handle_tracepoint_bkpts (tinfo
, lwp
->stop_pc
);
1941 /* See if we just hit a tracepoint and do its main collect
1943 tpoint_related_event
|= tracepoint_was_hit (tinfo
, lwp
->stop_pc
);
1945 lwp_suspended_decr (lwp
);
1947 gdb_assert (lwp
->suspended
== 0);
1948 gdb_assert (!stabilizing_threads
1949 || (lwp
->collecting_fast_tracepoint
1950 != fast_tpoint_collect_result::not_collecting
));
1952 if (tpoint_related_event
)
1955 debug_printf ("got a tracepoint event\n");
1962 fast_tpoint_collect_result
1963 linux_process_target::linux_fast_tracepoint_collecting
1964 (lwp_info
*lwp
, fast_tpoint_collect_status
*status
)
1966 CORE_ADDR thread_area
;
1967 struct thread_info
*thread
= get_lwp_thread (lwp
);
1969 /* Get the thread area address. This is used to recognize which
1970 thread is which when tracing with the in-process agent library.
1971 We don't read anything from the address, and treat it as opaque;
1972 it's the address itself that we assume is unique per-thread. */
1973 if (low_get_thread_area (lwpid_of (thread
), &thread_area
) == -1)
1974 return fast_tpoint_collect_result::not_collecting
;
1976 return fast_tracepoint_collecting (thread_area
, lwp
->stop_pc
, status
);
1980 linux_process_target::low_get_thread_area (int lwpid
, CORE_ADDR
*addrp
)
1986 linux_process_target::maybe_move_out_of_jump_pad (lwp_info
*lwp
, int *wstat
)
1988 struct thread_info
*saved_thread
;
1990 saved_thread
= current_thread
;
1991 current_thread
= get_lwp_thread (lwp
);
1994 || (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) != SIGTRAP
))
1995 && supports_fast_tracepoints ()
1996 && agent_loaded_p ())
1998 struct fast_tpoint_collect_status status
;
2001 debug_printf ("Checking whether LWP %ld needs to move out of the "
2003 lwpid_of (current_thread
));
2005 fast_tpoint_collect_result r
2006 = linux_fast_tracepoint_collecting (lwp
, &status
);
2009 || (WSTOPSIG (*wstat
) != SIGILL
2010 && WSTOPSIG (*wstat
) != SIGFPE
2011 && WSTOPSIG (*wstat
) != SIGSEGV
2012 && WSTOPSIG (*wstat
) != SIGBUS
))
2014 lwp
->collecting_fast_tracepoint
= r
;
2016 if (r
!= fast_tpoint_collect_result::not_collecting
)
2018 if (r
== fast_tpoint_collect_result::before_insn
2019 && lwp
->exit_jump_pad_bkpt
== NULL
)
2021 /* Haven't executed the original instruction yet.
2022 Set breakpoint there, and wait till it's hit,
2023 then single-step until exiting the jump pad. */
2024 lwp
->exit_jump_pad_bkpt
2025 = set_breakpoint_at (status
.adjusted_insn_addr
, NULL
);
2029 debug_printf ("Checking whether LWP %ld needs to move out of "
2030 "the jump pad...it does\n",
2031 lwpid_of (current_thread
));
2032 current_thread
= saved_thread
;
2039 /* If we get a synchronous signal while collecting, *and*
2040 while executing the (relocated) original instruction,
2041 reset the PC to point at the tpoint address, before
2042 reporting to GDB. Otherwise, it's an IPA lib bug: just
2043 report the signal to GDB, and pray for the best. */
2045 lwp
->collecting_fast_tracepoint
2046 = fast_tpoint_collect_result::not_collecting
;
2048 if (r
!= fast_tpoint_collect_result::not_collecting
2049 && (status
.adjusted_insn_addr
<= lwp
->stop_pc
2050 && lwp
->stop_pc
< status
.adjusted_insn_addr_end
))
2053 struct regcache
*regcache
;
2055 /* The si_addr on a few signals references the address
2056 of the faulting instruction. Adjust that as
2058 if ((WSTOPSIG (*wstat
) == SIGILL
2059 || WSTOPSIG (*wstat
) == SIGFPE
2060 || WSTOPSIG (*wstat
) == SIGBUS
2061 || WSTOPSIG (*wstat
) == SIGSEGV
)
2062 && ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
2063 (PTRACE_TYPE_ARG3
) 0, &info
) == 0
2064 /* Final check just to make sure we don't clobber
2065 the siginfo of non-kernel-sent signals. */
2066 && (uintptr_t) info
.si_addr
== lwp
->stop_pc
)
2068 info
.si_addr
= (void *) (uintptr_t) status
.tpoint_addr
;
2069 ptrace (PTRACE_SETSIGINFO
, lwpid_of (current_thread
),
2070 (PTRACE_TYPE_ARG3
) 0, &info
);
2073 regcache
= get_thread_regcache (current_thread
, 1);
2074 low_set_pc (regcache
, status
.tpoint_addr
);
2075 lwp
->stop_pc
= status
.tpoint_addr
;
2077 /* Cancel any fast tracepoint lock this thread was
2079 force_unlock_trace_buffer ();
2082 if (lwp
->exit_jump_pad_bkpt
!= NULL
)
2085 debug_printf ("Cancelling fast exit-jump-pad: removing bkpt. "
2086 "stopping all threads momentarily.\n");
2088 stop_all_lwps (1, lwp
);
2090 delete_breakpoint (lwp
->exit_jump_pad_bkpt
);
2091 lwp
->exit_jump_pad_bkpt
= NULL
;
2093 unstop_all_lwps (1, lwp
);
2095 gdb_assert (lwp
->suspended
>= 0);
2101 debug_printf ("Checking whether LWP %ld needs to move out of the "
2103 lwpid_of (current_thread
));
2105 current_thread
= saved_thread
;
2109 /* Enqueue one signal in the "signals to report later when out of the
2113 enqueue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
2115 struct thread_info
*thread
= get_lwp_thread (lwp
);
2118 debug_printf ("Deferring signal %d for LWP %ld.\n",
2119 WSTOPSIG (*wstat
), lwpid_of (thread
));
2123 for (const auto &sig
: lwp
->pending_signals_to_report
)
2124 debug_printf (" Already queued %d\n",
2127 debug_printf (" (no more currently queued signals)\n");
2130 /* Don't enqueue non-RT signals if they are already in the deferred
2131 queue. (SIGSTOP being the easiest signal to see ending up here
2133 if (WSTOPSIG (*wstat
) < __SIGRTMIN
)
2135 for (const auto &sig
: lwp
->pending_signals_to_report
)
2137 if (sig
.signal
== WSTOPSIG (*wstat
))
2140 debug_printf ("Not requeuing already queued non-RT signal %d"
2149 lwp
->pending_signals_to_report
.emplace_back (WSTOPSIG (*wstat
));
2151 ptrace (PTRACE_GETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
2152 &lwp
->pending_signals_to_report
.back ().info
);
2155 /* Dequeue one signal from the "signals to report later when out of
2156 the jump pad" list. */
2159 dequeue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
2161 struct thread_info
*thread
= get_lwp_thread (lwp
);
2163 if (!lwp
->pending_signals_to_report
.empty ())
2165 const pending_signal
&p_sig
= lwp
->pending_signals_to_report
.front ();
2167 *wstat
= W_STOPCODE (p_sig
.signal
);
2168 if (p_sig
.info
.si_signo
!= 0)
2169 ptrace (PTRACE_SETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
2172 lwp
->pending_signals_to_report
.pop_front ();
2175 debug_printf ("Reporting deferred signal %d for LWP %ld.\n",
2176 WSTOPSIG (*wstat
), lwpid_of (thread
));
2180 for (const auto &sig
: lwp
->pending_signals_to_report
)
2181 debug_printf (" Still queued %d\n",
2184 debug_printf (" (no more queued signals)\n");
2194 linux_process_target::check_stopped_by_watchpoint (lwp_info
*child
)
2196 struct thread_info
*saved_thread
= current_thread
;
2197 current_thread
= get_lwp_thread (child
);
2199 if (low_stopped_by_watchpoint ())
2201 child
->stop_reason
= TARGET_STOPPED_BY_WATCHPOINT
;
2202 child
->stopped_data_address
= low_stopped_data_address ();
2205 current_thread
= saved_thread
;
2207 return child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
;
2211 linux_process_target::low_stopped_by_watchpoint ()
2217 linux_process_target::low_stopped_data_address ()
2222 /* Return the ptrace options that we want to try to enable. */
2225 linux_low_ptrace_options (int attached
)
2227 client_state
&cs
= get_client_state ();
2231 options
|= PTRACE_O_EXITKILL
;
2233 if (cs
.report_fork_events
)
2234 options
|= PTRACE_O_TRACEFORK
;
2236 if (cs
.report_vfork_events
)
2237 options
|= (PTRACE_O_TRACEVFORK
| PTRACE_O_TRACEVFORKDONE
);
2239 if (cs
.report_exec_events
)
2240 options
|= PTRACE_O_TRACEEXEC
;
2242 options
|= PTRACE_O_TRACESYSGOOD
;
2248 linux_process_target::filter_event (int lwpid
, int wstat
)
2250 client_state
&cs
= get_client_state ();
2251 struct lwp_info
*child
;
2252 struct thread_info
*thread
;
2253 int have_stop_pc
= 0;
2255 child
= find_lwp_pid (ptid_t (lwpid
));
2257 /* Check for stop events reported by a process we didn't already
2258 know about - anything not already in our LWP list.
2260 If we're expecting to receive stopped processes after
2261 fork, vfork, and clone events, then we'll just add the
2262 new one to our list and go back to waiting for the event
2263 to be reported - the stopped process might be returned
2264 from waitpid before or after the event is.
2266 But note the case of a non-leader thread exec'ing after the
2267 leader having exited, and gone from our lists (because
2268 check_zombie_leaders deleted it). The non-leader thread
2269 changes its tid to the tgid. */
2271 if (WIFSTOPPED (wstat
) && child
== NULL
&& WSTOPSIG (wstat
) == SIGTRAP
2272 && linux_ptrace_get_extended_event (wstat
) == PTRACE_EVENT_EXEC
)
2276 /* A multi-thread exec after we had seen the leader exiting. */
2279 debug_printf ("LLW: Re-adding thread group leader LWP %d"
2280 "after exec.\n", lwpid
);
2283 child_ptid
= ptid_t (lwpid
, lwpid
, 0);
2284 child
= add_lwp (child_ptid
);
2286 current_thread
= child
->thread
;
2289 /* If we didn't find a process, one of two things presumably happened:
2290 - A process we started and then detached from has exited. Ignore it.
2291 - A process we are controlling has forked and the new child's stop
2292 was reported to us by the kernel. Save its PID. */
2293 if (child
== NULL
&& WIFSTOPPED (wstat
))
2295 add_to_pid_list (&stopped_pids
, lwpid
, wstat
);
2298 else if (child
== NULL
)
2301 thread
= get_lwp_thread (child
);
2305 child
->last_status
= wstat
;
2307 /* Check if the thread has exited. */
2308 if ((WIFEXITED (wstat
) || WIFSIGNALED (wstat
)))
2311 debug_printf ("LLFE: %d exited.\n", lwpid
);
2313 if (finish_step_over (child
))
2315 /* Unsuspend all other LWPs, and set them back running again. */
2316 unsuspend_all_lwps (child
);
2319 /* If there is at least one more LWP, then the exit signal was
2320 not the end of the debugged application and should be
2321 ignored, unless GDB wants to hear about thread exits. */
2322 if (cs
.report_thread_events
2323 || last_thread_of_process_p (pid_of (thread
)))
2325 /* Since events are serialized to GDB core, and we can't
2326 report this one right now. Leave the status pending for
2327 the next time we're able to report it. */
2328 mark_lwp_dead (child
, wstat
);
2338 gdb_assert (WIFSTOPPED (wstat
));
2340 if (WIFSTOPPED (wstat
))
2342 struct process_info
*proc
;
2344 /* Architecture-specific setup after inferior is running. */
2345 proc
= find_process_pid (pid_of (thread
));
2346 if (proc
->tdesc
== NULL
)
2350 /* This needs to happen after we have attached to the
2351 inferior and it is stopped for the first time, but
2352 before we access any inferior registers. */
2353 arch_setup_thread (thread
);
2357 /* The process is started, but GDBserver will do
2358 architecture-specific setup after the program stops at
2359 the first instruction. */
2360 child
->status_pending_p
= 1;
2361 child
->status_pending
= wstat
;
2367 if (WIFSTOPPED (wstat
) && child
->must_set_ptrace_flags
)
2369 struct process_info
*proc
= find_process_pid (pid_of (thread
));
2370 int options
= linux_low_ptrace_options (proc
->attached
);
2372 linux_enable_event_reporting (lwpid
, options
);
2373 child
->must_set_ptrace_flags
= 0;
2376 /* Always update syscall_state, even if it will be filtered later. */
2377 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SYSCALL_SIGTRAP
)
2379 child
->syscall_state
2380 = (child
->syscall_state
== TARGET_WAITKIND_SYSCALL_ENTRY
2381 ? TARGET_WAITKIND_SYSCALL_RETURN
2382 : TARGET_WAITKIND_SYSCALL_ENTRY
);
2386 /* Almost all other ptrace-stops are known to be outside of system
2387 calls, with further exceptions in handle_extended_wait. */
2388 child
->syscall_state
= TARGET_WAITKIND_IGNORE
;
2391 /* Be careful to not overwrite stop_pc until save_stop_reason is
2393 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGTRAP
2394 && linux_is_extended_waitstatus (wstat
))
2396 child
->stop_pc
= get_pc (child
);
2397 if (handle_extended_wait (&child
, wstat
))
2399 /* The event has been handled, so just return without
2405 if (linux_wstatus_maybe_breakpoint (wstat
))
2407 if (save_stop_reason (child
))
2412 child
->stop_pc
= get_pc (child
);
2414 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGSTOP
2415 && child
->stop_expected
)
2418 debug_printf ("Expected stop.\n");
2419 child
->stop_expected
= 0;
2421 if (thread
->last_resume_kind
== resume_stop
)
2423 /* We want to report the stop to the core. Treat the
2424 SIGSTOP as a normal event. */
2426 debug_printf ("LLW: resume_stop SIGSTOP caught for %s.\n",
2427 target_pid_to_str (ptid_of (thread
)));
2429 else if (stopping_threads
!= NOT_STOPPING_THREADS
)
2431 /* Stopping threads. We don't want this SIGSTOP to end up
2434 debug_printf ("LLW: SIGSTOP caught for %s "
2435 "while stopping threads.\n",
2436 target_pid_to_str (ptid_of (thread
)));
2441 /* This is a delayed SIGSTOP. Filter out the event. */
2443 debug_printf ("LLW: %s %s, 0, 0 (discard delayed SIGSTOP)\n",
2444 child
->stepping
? "step" : "continue",
2445 target_pid_to_str (ptid_of (thread
)));
2447 resume_one_lwp (child
, child
->stepping
, 0, NULL
);
2452 child
->status_pending_p
= 1;
2453 child
->status_pending
= wstat
;
2458 linux_process_target::maybe_hw_step (thread_info
*thread
)
2460 if (supports_hardware_single_step ())
2464 /* GDBserver must insert single-step breakpoint for software
2466 gdb_assert (has_single_step_breakpoints (thread
));
2472 linux_process_target::resume_stopped_resumed_lwps (thread_info
*thread
)
2474 struct lwp_info
*lp
= get_thread_lwp (thread
);
2478 && !lp
->status_pending_p
2479 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
)
2483 if (thread
->last_resume_kind
== resume_step
)
2484 step
= maybe_hw_step (thread
);
2487 debug_printf ("RSRL: resuming stopped-resumed LWP %s at %s: step=%d\n",
2488 target_pid_to_str (ptid_of (thread
)),
2489 paddress (lp
->stop_pc
),
2492 resume_one_lwp (lp
, step
, GDB_SIGNAL_0
, NULL
);
2497 linux_process_target::wait_for_event_filtered (ptid_t wait_ptid
,
2499 int *wstatp
, int options
)
2501 struct thread_info
*event_thread
;
2502 struct lwp_info
*event_child
, *requested_child
;
2503 sigset_t block_mask
, prev_mask
;
2506 /* N.B. event_thread points to the thread_info struct that contains
2507 event_child. Keep them in sync. */
2508 event_thread
= NULL
;
2510 requested_child
= NULL
;
2512 /* Check for a lwp with a pending status. */
2514 if (filter_ptid
== minus_one_ptid
|| filter_ptid
.is_pid ())
2516 event_thread
= find_thread_in_random ([&] (thread_info
*thread
)
2518 return status_pending_p_callback (thread
, filter_ptid
);
2521 if (event_thread
!= NULL
)
2522 event_child
= get_thread_lwp (event_thread
);
2523 if (debug_threads
&& event_thread
)
2524 debug_printf ("Got a pending child %ld\n", lwpid_of (event_thread
));
2526 else if (filter_ptid
!= null_ptid
)
2528 requested_child
= find_lwp_pid (filter_ptid
);
2530 if (stopping_threads
== NOT_STOPPING_THREADS
2531 && requested_child
->status_pending_p
2532 && (requested_child
->collecting_fast_tracepoint
2533 != fast_tpoint_collect_result::not_collecting
))
2535 enqueue_one_deferred_signal (requested_child
,
2536 &requested_child
->status_pending
);
2537 requested_child
->status_pending_p
= 0;
2538 requested_child
->status_pending
= 0;
2539 resume_one_lwp (requested_child
, 0, 0, NULL
);
2542 if (requested_child
->suspended
2543 && requested_child
->status_pending_p
)
2545 internal_error (__FILE__
, __LINE__
,
2546 "requesting an event out of a"
2547 " suspended child?");
2550 if (requested_child
->status_pending_p
)
2552 event_child
= requested_child
;
2553 event_thread
= get_lwp_thread (event_child
);
2557 if (event_child
!= NULL
)
2560 debug_printf ("Got an event from pending child %ld (%04x)\n",
2561 lwpid_of (event_thread
), event_child
->status_pending
);
2562 *wstatp
= event_child
->status_pending
;
2563 event_child
->status_pending_p
= 0;
2564 event_child
->status_pending
= 0;
2565 current_thread
= event_thread
;
2566 return lwpid_of (event_thread
);
2569 /* But if we don't find a pending event, we'll have to wait.
2571 We only enter this loop if no process has a pending wait status.
2572 Thus any action taken in response to a wait status inside this
2573 loop is responding as soon as we detect the status, not after any
2576 /* Make sure SIGCHLD is blocked until the sigsuspend below. Block
2577 all signals while here. */
2578 sigfillset (&block_mask
);
2579 gdb_sigmask (SIG_BLOCK
, &block_mask
, &prev_mask
);
2581 /* Always pull all events out of the kernel. We'll randomly select
2582 an event LWP out of all that have events, to prevent
2584 while (event_child
== NULL
)
2588 /* Always use -1 and WNOHANG, due to couple of a kernel/ptrace
2591 - If the thread group leader exits while other threads in the
2592 thread group still exist, waitpid(TGID, ...) hangs. That
2593 waitpid won't return an exit status until the other threads
2594 in the group are reaped.
2596 - When a non-leader thread execs, that thread just vanishes
2597 without reporting an exit (so we'd hang if we waited for it
2598 explicitly in that case). The exec event is reported to
2601 ret
= my_waitpid (-1, wstatp
, options
| WNOHANG
);
2604 debug_printf ("LWFE: waitpid(-1, ...) returned %d, %s\n",
2605 ret
, errno
? safe_strerror (errno
) : "ERRNO-OK");
2611 debug_printf ("LLW: waitpid %ld received %s\n",
2612 (long) ret
, status_to_str (*wstatp
));
2615 /* Filter all events. IOW, leave all events pending. We'll
2616 randomly select an event LWP out of all that have events
2618 filter_event (ret
, *wstatp
);
2619 /* Retry until nothing comes out of waitpid. A single
2620 SIGCHLD can indicate more than one child stopped. */
2624 /* Now that we've pulled all events out of the kernel, resume
2625 LWPs that don't have an interesting event to report. */
2626 if (stopping_threads
== NOT_STOPPING_THREADS
)
2627 for_each_thread ([this] (thread_info
*thread
)
2629 resume_stopped_resumed_lwps (thread
);
2632 /* ... and find an LWP with a status to report to the core, if
2634 event_thread
= find_thread_in_random ([&] (thread_info
*thread
)
2636 return status_pending_p_callback (thread
, filter_ptid
);
2639 if (event_thread
!= NULL
)
2641 event_child
= get_thread_lwp (event_thread
);
2642 *wstatp
= event_child
->status_pending
;
2643 event_child
->status_pending_p
= 0;
2644 event_child
->status_pending
= 0;
2648 /* Check for zombie thread group leaders. Those can't be reaped
2649 until all other threads in the thread group are. */
2650 check_zombie_leaders ();
2652 auto not_stopped
= [&] (thread_info
*thread
)
2654 return not_stopped_callback (thread
, wait_ptid
);
2657 /* If there are no resumed children left in the set of LWPs we
2658 want to wait for, bail. We can't just block in
2659 waitpid/sigsuspend, because lwps might have been left stopped
2660 in trace-stop state, and we'd be stuck forever waiting for
2661 their status to change (which would only happen if we resumed
2662 them). Even if WNOHANG is set, this return code is preferred
2663 over 0 (below), as it is more detailed. */
2664 if (find_thread (not_stopped
) == NULL
)
2667 debug_printf ("LLW: exit (no unwaited-for LWP)\n");
2668 gdb_sigmask (SIG_SETMASK
, &prev_mask
, NULL
);
2672 /* No interesting event to report to the caller. */
2673 if ((options
& WNOHANG
))
2676 debug_printf ("WNOHANG set, no event found\n");
2678 gdb_sigmask (SIG_SETMASK
, &prev_mask
, NULL
);
2682 /* Block until we get an event reported with SIGCHLD. */
2684 debug_printf ("sigsuspend'ing\n");
2686 sigsuspend (&prev_mask
);
2687 gdb_sigmask (SIG_SETMASK
, &prev_mask
, NULL
);
2691 gdb_sigmask (SIG_SETMASK
, &prev_mask
, NULL
);
2693 current_thread
= event_thread
;
2695 return lwpid_of (event_thread
);
2699 linux_process_target::wait_for_event (ptid_t ptid
, int *wstatp
, int options
)
2701 return wait_for_event_filtered (ptid
, ptid
, wstatp
, options
);
2704 /* Select one LWP out of those that have events pending. */
2707 select_event_lwp (struct lwp_info
**orig_lp
)
2709 struct thread_info
*event_thread
= NULL
;
2711 /* In all-stop, give preference to the LWP that is being
2712 single-stepped. There will be at most one, and it's the LWP that
2713 the core is most interested in. If we didn't do this, then we'd
2714 have to handle pending step SIGTRAPs somehow in case the core
2715 later continues the previously-stepped thread, otherwise we'd
2716 report the pending SIGTRAP, and the core, not having stepped the
2717 thread, wouldn't understand what the trap was for, and therefore
2718 would report it to the user as a random signal. */
2721 event_thread
= find_thread ([] (thread_info
*thread
)
2723 lwp_info
*lp
= get_thread_lwp (thread
);
2725 return (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2726 && thread
->last_resume_kind
== resume_step
2727 && lp
->status_pending_p
);
2730 if (event_thread
!= NULL
)
2733 debug_printf ("SEL: Select single-step %s\n",
2734 target_pid_to_str (ptid_of (event_thread
)));
2737 if (event_thread
== NULL
)
2739 /* No single-stepping LWP. Select one at random, out of those
2740 which have had events. */
2742 event_thread
= find_thread_in_random ([&] (thread_info
*thread
)
2744 lwp_info
*lp
= get_thread_lwp (thread
);
2746 /* Only resumed LWPs that have an event pending. */
2747 return (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2748 && lp
->status_pending_p
);
2752 if (event_thread
!= NULL
)
2754 struct lwp_info
*event_lp
= get_thread_lwp (event_thread
);
2756 /* Switch the event LWP. */
2757 *orig_lp
= event_lp
;
2761 /* Decrement the suspend count of all LWPs, except EXCEPT, if non
2765 unsuspend_all_lwps (struct lwp_info
*except
)
2767 for_each_thread ([&] (thread_info
*thread
)
2769 lwp_info
*lwp
= get_thread_lwp (thread
);
2772 lwp_suspended_decr (lwp
);
2776 static bool lwp_running (thread_info
*thread
);
2778 /* Stabilize threads (move out of jump pads).
2780 If a thread is midway collecting a fast tracepoint, we need to
2781 finish the collection and move it out of the jump pad before
2782 reporting the signal.
2784 This avoids recursion while collecting (when a signal arrives
2785 midway, and the signal handler itself collects), which would trash
2786 the trace buffer. In case the user set a breakpoint in a signal
2787 handler, this avoids the backtrace showing the jump pad, etc..
2788 Most importantly, there are certain things we can't do safely if
2789 threads are stopped in a jump pad (or in its callee's). For
2792 - starting a new trace run. A thread still collecting the
2793 previous run, could trash the trace buffer when resumed. The trace
2794 buffer control structures would have been reset but the thread had
2795 no way to tell. The thread could even midway memcpy'ing to the
2796 buffer, which would mean that when resumed, it would clobber the
2797 trace buffer that had been set for a new run.
2799 - we can't rewrite/reuse the jump pads for new tracepoints
2800 safely. Say you do tstart while a thread is stopped midway while
2801 collecting. When the thread is later resumed, it finishes the
2802 collection, and returns to the jump pad, to execute the original
2803 instruction that was under the tracepoint jump at the time the
2804 older run had been started. If the jump pad had been rewritten
2805 since for something else in the new run, the thread would now
2806 execute the wrong / random instructions. */
2809 linux_process_target::stabilize_threads ()
2811 thread_info
*thread_stuck
= find_thread ([this] (thread_info
*thread
)
2813 return stuck_in_jump_pad (thread
);
2816 if (thread_stuck
!= NULL
)
2819 debug_printf ("can't stabilize, LWP %ld is stuck in jump pad\n",
2820 lwpid_of (thread_stuck
));
2824 thread_info
*saved_thread
= current_thread
;
2826 stabilizing_threads
= 1;
2829 for_each_thread ([this] (thread_info
*thread
)
2831 move_out_of_jump_pad (thread
);
2834 /* Loop until all are stopped out of the jump pads. */
2835 while (find_thread (lwp_running
) != NULL
)
2837 struct target_waitstatus ourstatus
;
2838 struct lwp_info
*lwp
;
2841 /* Note that we go through the full wait even loop. While
2842 moving threads out of jump pad, we need to be able to step
2843 over internal breakpoints and such. */
2844 wait_1 (minus_one_ptid
, &ourstatus
, 0);
2846 if (ourstatus
.kind
== TARGET_WAITKIND_STOPPED
)
2848 lwp
= get_thread_lwp (current_thread
);
2851 lwp_suspended_inc (lwp
);
2853 if (ourstatus
.value
.sig
!= GDB_SIGNAL_0
2854 || current_thread
->last_resume_kind
== resume_stop
)
2856 wstat
= W_STOPCODE (gdb_signal_to_host (ourstatus
.value
.sig
));
2857 enqueue_one_deferred_signal (lwp
, &wstat
);
2862 unsuspend_all_lwps (NULL
);
2864 stabilizing_threads
= 0;
2866 current_thread
= saved_thread
;
2870 thread_stuck
= find_thread ([this] (thread_info
*thread
)
2872 return stuck_in_jump_pad (thread
);
2875 if (thread_stuck
!= NULL
)
2876 debug_printf ("couldn't stabilize, LWP %ld got stuck in jump pad\n",
2877 lwpid_of (thread_stuck
));
2881 /* Convenience function that is called when the kernel reports an
2882 event that is not passed out to GDB. */
2885 ignore_event (struct target_waitstatus
*ourstatus
)
2887 /* If we got an event, there may still be others, as a single
2888 SIGCHLD can indicate more than one child stopped. This forces
2889 another target_wait call. */
2892 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2897 linux_process_target::filter_exit_event (lwp_info
*event_child
,
2898 target_waitstatus
*ourstatus
)
2900 client_state
&cs
= get_client_state ();
2901 struct thread_info
*thread
= get_lwp_thread (event_child
);
2902 ptid_t ptid
= ptid_of (thread
);
2904 if (!last_thread_of_process_p (pid_of (thread
)))
2906 if (cs
.report_thread_events
)
2907 ourstatus
->kind
= TARGET_WAITKIND_THREAD_EXITED
;
2909 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2911 delete_lwp (event_child
);
2916 /* Returns 1 if GDB is interested in any event_child syscalls. */
2919 gdb_catching_syscalls_p (struct lwp_info
*event_child
)
2921 struct thread_info
*thread
= get_lwp_thread (event_child
);
2922 struct process_info
*proc
= get_thread_process (thread
);
2924 return !proc
->syscalls_to_catch
.empty ();
2928 linux_process_target::gdb_catch_this_syscall (lwp_info
*event_child
)
2931 struct thread_info
*thread
= get_lwp_thread (event_child
);
2932 struct process_info
*proc
= get_thread_process (thread
);
2934 if (proc
->syscalls_to_catch
.empty ())
2937 if (proc
->syscalls_to_catch
[0] == ANY_SYSCALL
)
2940 get_syscall_trapinfo (event_child
, &sysno
);
2942 for (int iter
: proc
->syscalls_to_catch
)
2950 linux_process_target::wait_1 (ptid_t ptid
, target_waitstatus
*ourstatus
,
2953 client_state
&cs
= get_client_state ();
2955 struct lwp_info
*event_child
;
2958 int step_over_finished
;
2959 int bp_explains_trap
;
2960 int maybe_internal_trap
;
2969 debug_printf ("wait_1: [%s]\n", target_pid_to_str (ptid
));
2972 /* Translate generic target options into linux options. */
2974 if (target_options
& TARGET_WNOHANG
)
2977 bp_explains_trap
= 0;
2980 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2982 auto status_pending_p_any
= [&] (thread_info
*thread
)
2984 return status_pending_p_callback (thread
, minus_one_ptid
);
2987 auto not_stopped
= [&] (thread_info
*thread
)
2989 return not_stopped_callback (thread
, minus_one_ptid
);
2992 /* Find a resumed LWP, if any. */
2993 if (find_thread (status_pending_p_any
) != NULL
)
2995 else if (find_thread (not_stopped
) != NULL
)
3000 if (step_over_bkpt
== null_ptid
)
3001 pid
= wait_for_event (ptid
, &w
, options
);
3005 debug_printf ("step_over_bkpt set [%s], doing a blocking wait\n",
3006 target_pid_to_str (step_over_bkpt
));
3007 pid
= wait_for_event (step_over_bkpt
, &w
, options
& ~WNOHANG
);
3010 if (pid
== 0 || (pid
== -1 && !any_resumed
))
3012 gdb_assert (target_options
& TARGET_WNOHANG
);
3016 debug_printf ("wait_1 ret = null_ptid, "
3017 "TARGET_WAITKIND_IGNORE\n");
3021 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3028 debug_printf ("wait_1 ret = null_ptid, "
3029 "TARGET_WAITKIND_NO_RESUMED\n");
3033 ourstatus
->kind
= TARGET_WAITKIND_NO_RESUMED
;
3037 event_child
= get_thread_lwp (current_thread
);
3039 /* wait_for_event only returns an exit status for the last
3040 child of a process. Report it. */
3041 if (WIFEXITED (w
) || WIFSIGNALED (w
))
3045 ourstatus
->kind
= TARGET_WAITKIND_EXITED
;
3046 ourstatus
->value
.integer
= WEXITSTATUS (w
);
3050 debug_printf ("wait_1 ret = %s, exited with "
3052 target_pid_to_str (ptid_of (current_thread
)),
3059 ourstatus
->kind
= TARGET_WAITKIND_SIGNALLED
;
3060 ourstatus
->value
.sig
= gdb_signal_from_host (WTERMSIG (w
));
3064 debug_printf ("wait_1 ret = %s, terminated with "
3066 target_pid_to_str (ptid_of (current_thread
)),
3072 if (ourstatus
->kind
== TARGET_WAITKIND_EXITED
)
3073 return filter_exit_event (event_child
, ourstatus
);
3075 return ptid_of (current_thread
);
3078 /* If step-over executes a breakpoint instruction, in the case of a
3079 hardware single step it means a gdb/gdbserver breakpoint had been
3080 planted on top of a permanent breakpoint, in the case of a software
3081 single step it may just mean that gdbserver hit the reinsert breakpoint.
3082 The PC has been adjusted by save_stop_reason to point at
3083 the breakpoint address.
3084 So in the case of the hardware single step advance the PC manually
3085 past the breakpoint and in the case of software single step advance only
3086 if it's not the single_step_breakpoint we are hitting.
3087 This avoids that a program would keep trapping a permanent breakpoint
3089 if (step_over_bkpt
!= null_ptid
3090 && event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3091 && (event_child
->stepping
3092 || !single_step_breakpoint_inserted_here (event_child
->stop_pc
)))
3094 int increment_pc
= 0;
3095 int breakpoint_kind
= 0;
3096 CORE_ADDR stop_pc
= event_child
->stop_pc
;
3098 breakpoint_kind
= breakpoint_kind_from_current_state (&stop_pc
);
3099 sw_breakpoint_from_kind (breakpoint_kind
, &increment_pc
);
3103 debug_printf ("step-over for %s executed software breakpoint\n",
3104 target_pid_to_str (ptid_of (current_thread
)));
3107 if (increment_pc
!= 0)
3109 struct regcache
*regcache
3110 = get_thread_regcache (current_thread
, 1);
3112 event_child
->stop_pc
+= increment_pc
;
3113 low_set_pc (regcache
, event_child
->stop_pc
);
3115 if (!low_breakpoint_at (event_child
->stop_pc
))
3116 event_child
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3120 /* If this event was not handled before, and is not a SIGTRAP, we
3121 report it. SIGILL and SIGSEGV are also treated as traps in case
3122 a breakpoint is inserted at the current PC. If this target does
3123 not support internal breakpoints at all, we also report the
3124 SIGTRAP without further processing; it's of no concern to us. */
3126 = (low_supports_breakpoints ()
3127 && (WSTOPSIG (w
) == SIGTRAP
3128 || ((WSTOPSIG (w
) == SIGILL
3129 || WSTOPSIG (w
) == SIGSEGV
)
3130 && low_breakpoint_at (event_child
->stop_pc
))));
3132 if (maybe_internal_trap
)
3134 /* Handle anything that requires bookkeeping before deciding to
3135 report the event or continue waiting. */
3137 /* First check if we can explain the SIGTRAP with an internal
3138 breakpoint, or if we should possibly report the event to GDB.
3139 Do this before anything that may remove or insert a
3141 bp_explains_trap
= breakpoint_inserted_here (event_child
->stop_pc
);
3143 /* We have a SIGTRAP, possibly a step-over dance has just
3144 finished. If so, tweak the state machine accordingly,
3145 reinsert breakpoints and delete any single-step
3147 step_over_finished
= finish_step_over (event_child
);
3149 /* Now invoke the callbacks of any internal breakpoints there. */
3150 check_breakpoints (event_child
->stop_pc
);
3152 /* Handle tracepoint data collecting. This may overflow the
3153 trace buffer, and cause a tracing stop, removing
3155 trace_event
= handle_tracepoints (event_child
);
3157 if (bp_explains_trap
)
3160 debug_printf ("Hit a gdbserver breakpoint.\n");
3165 /* We have some other signal, possibly a step-over dance was in
3166 progress, and it should be cancelled too. */
3167 step_over_finished
= finish_step_over (event_child
);
3170 /* We have all the data we need. Either report the event to GDB, or
3171 resume threads and keep waiting for more. */
3173 /* If we're collecting a fast tracepoint, finish the collection and
3174 move out of the jump pad before delivering a signal. See
3175 linux_stabilize_threads. */
3178 && WSTOPSIG (w
) != SIGTRAP
3179 && supports_fast_tracepoints ()
3180 && agent_loaded_p ())
3183 debug_printf ("Got signal %d for LWP %ld. Check if we need "
3184 "to defer or adjust it.\n",
3185 WSTOPSIG (w
), lwpid_of (current_thread
));
3187 /* Allow debugging the jump pad itself. */
3188 if (current_thread
->last_resume_kind
!= resume_step
3189 && maybe_move_out_of_jump_pad (event_child
, &w
))
3191 enqueue_one_deferred_signal (event_child
, &w
);
3194 debug_printf ("Signal %d for LWP %ld deferred (in jump pad)\n",
3195 WSTOPSIG (w
), lwpid_of (current_thread
));
3197 resume_one_lwp (event_child
, 0, 0, NULL
);
3201 return ignore_event (ourstatus
);
3205 if (event_child
->collecting_fast_tracepoint
3206 != fast_tpoint_collect_result::not_collecting
)
3209 debug_printf ("LWP %ld was trying to move out of the jump pad (%d). "
3210 "Check if we're already there.\n",
3211 lwpid_of (current_thread
),
3212 (int) event_child
->collecting_fast_tracepoint
);
3216 event_child
->collecting_fast_tracepoint
3217 = linux_fast_tracepoint_collecting (event_child
, NULL
);
3219 if (event_child
->collecting_fast_tracepoint
3220 != fast_tpoint_collect_result::before_insn
)
3222 /* No longer need this breakpoint. */
3223 if (event_child
->exit_jump_pad_bkpt
!= NULL
)
3226 debug_printf ("No longer need exit-jump-pad bkpt; removing it."
3227 "stopping all threads momentarily.\n");
3229 /* Other running threads could hit this breakpoint.
3230 We don't handle moribund locations like GDB does,
3231 instead we always pause all threads when removing
3232 breakpoints, so that any step-over or
3233 decr_pc_after_break adjustment is always taken
3234 care of while the breakpoint is still
3236 stop_all_lwps (1, event_child
);
3238 delete_breakpoint (event_child
->exit_jump_pad_bkpt
);
3239 event_child
->exit_jump_pad_bkpt
= NULL
;
3241 unstop_all_lwps (1, event_child
);
3243 gdb_assert (event_child
->suspended
>= 0);
3247 if (event_child
->collecting_fast_tracepoint
3248 == fast_tpoint_collect_result::not_collecting
)
3251 debug_printf ("fast tracepoint finished "
3252 "collecting successfully.\n");
3254 /* We may have a deferred signal to report. */
3255 if (dequeue_one_deferred_signal (event_child
, &w
))
3258 debug_printf ("dequeued one signal.\n");
3263 debug_printf ("no deferred signals.\n");
3265 if (stabilizing_threads
)
3267 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
3268 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
3272 debug_printf ("wait_1 ret = %s, stopped "
3273 "while stabilizing threads\n",
3274 target_pid_to_str (ptid_of (current_thread
)));
3278 return ptid_of (current_thread
);
3284 /* Check whether GDB would be interested in this event. */
3286 /* Check if GDB is interested in this syscall. */
3288 && WSTOPSIG (w
) == SYSCALL_SIGTRAP
3289 && !gdb_catch_this_syscall (event_child
))
3293 debug_printf ("Ignored syscall for LWP %ld.\n",
3294 lwpid_of (current_thread
));
3297 resume_one_lwp (event_child
, event_child
->stepping
, 0, NULL
);
3301 return ignore_event (ourstatus
);
3304 /* If GDB is not interested in this signal, don't stop other
3305 threads, and don't report it to GDB. Just resume the inferior
3306 right away. We do this for threading-related signals as well as
3307 any that GDB specifically requested we ignore. But never ignore
3308 SIGSTOP if we sent it ourselves, and do not ignore signals when
3309 stepping - they may require special handling to skip the signal
3310 handler. Also never ignore signals that could be caused by a
3313 && current_thread
->last_resume_kind
!= resume_step
3315 #if defined (USE_THREAD_DB) && !defined (__ANDROID__)
3316 (current_process ()->priv
->thread_db
!= NULL
3317 && (WSTOPSIG (w
) == __SIGRTMIN
3318 || WSTOPSIG (w
) == __SIGRTMIN
+ 1))
3321 (cs
.pass_signals
[gdb_signal_from_host (WSTOPSIG (w
))]
3322 && !(WSTOPSIG (w
) == SIGSTOP
3323 && current_thread
->last_resume_kind
== resume_stop
)
3324 && !linux_wstatus_maybe_breakpoint (w
))))
3326 siginfo_t info
, *info_p
;
3329 debug_printf ("Ignored signal %d for LWP %ld.\n",
3330 WSTOPSIG (w
), lwpid_of (current_thread
));
3332 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
3333 (PTRACE_TYPE_ARG3
) 0, &info
) == 0)
3338 if (step_over_finished
)
3340 /* We cancelled this thread's step-over above. We still
3341 need to unsuspend all other LWPs, and set them back
3342 running again while the signal handler runs. */
3343 unsuspend_all_lwps (event_child
);
3345 /* Enqueue the pending signal info so that proceed_all_lwps
3347 enqueue_pending_signal (event_child
, WSTOPSIG (w
), info_p
);
3349 proceed_all_lwps ();
3353 resume_one_lwp (event_child
, event_child
->stepping
,
3354 WSTOPSIG (w
), info_p
);
3360 return ignore_event (ourstatus
);
3363 /* Note that all addresses are always "out of the step range" when
3364 there's no range to begin with. */
3365 in_step_range
= lwp_in_step_range (event_child
);
3367 /* If GDB wanted this thread to single step, and the thread is out
3368 of the step range, we always want to report the SIGTRAP, and let
3369 GDB handle it. Watchpoints should always be reported. So should
3370 signals we can't explain. A SIGTRAP we can't explain could be a
3371 GDB breakpoint --- we may or not support Z0 breakpoints. If we
3372 do, we're be able to handle GDB breakpoints on top of internal
3373 breakpoints, by handling the internal breakpoint and still
3374 reporting the event to GDB. If we don't, we're out of luck, GDB
3375 won't see the breakpoint hit. If we see a single-step event but
3376 the thread should be continuing, don't pass the trap to gdb.
3377 That indicates that we had previously finished a single-step but
3378 left the single-step pending -- see
3379 complete_ongoing_step_over. */
3380 report_to_gdb
= (!maybe_internal_trap
3381 || (current_thread
->last_resume_kind
== resume_step
3383 || event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
3385 && !bp_explains_trap
3387 && !step_over_finished
3388 && !(current_thread
->last_resume_kind
== resume_continue
3389 && event_child
->stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
))
3390 || (gdb_breakpoint_here (event_child
->stop_pc
)
3391 && gdb_condition_true_at_breakpoint (event_child
->stop_pc
)
3392 && gdb_no_commands_at_breakpoint (event_child
->stop_pc
))
3393 || event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
);
3395 run_breakpoint_commands (event_child
->stop_pc
);
3397 /* We found no reason GDB would want us to stop. We either hit one
3398 of our own breakpoints, or finished an internal step GDB
3399 shouldn't know about. */
3404 if (bp_explains_trap
)
3405 debug_printf ("Hit a gdbserver breakpoint.\n");
3406 if (step_over_finished
)
3407 debug_printf ("Step-over finished.\n");
3409 debug_printf ("Tracepoint event.\n");
3410 if (lwp_in_step_range (event_child
))
3411 debug_printf ("Range stepping pc 0x%s [0x%s, 0x%s).\n",
3412 paddress (event_child
->stop_pc
),
3413 paddress (event_child
->step_range_start
),
3414 paddress (event_child
->step_range_end
));
3417 /* We're not reporting this breakpoint to GDB, so apply the
3418 decr_pc_after_break adjustment to the inferior's regcache
3421 if (low_supports_breakpoints ())
3423 struct regcache
*regcache
3424 = get_thread_regcache (current_thread
, 1);
3425 low_set_pc (regcache
, event_child
->stop_pc
);
3428 if (step_over_finished
)
3430 /* If we have finished stepping over a breakpoint, we've
3431 stopped and suspended all LWPs momentarily except the
3432 stepping one. This is where we resume them all again.
3433 We're going to keep waiting, so use proceed, which
3434 handles stepping over the next breakpoint. */
3435 unsuspend_all_lwps (event_child
);
3439 /* Remove the single-step breakpoints if any. Note that
3440 there isn't single-step breakpoint if we finished stepping
3442 if (supports_software_single_step ()
3443 && has_single_step_breakpoints (current_thread
))
3445 stop_all_lwps (0, event_child
);
3446 delete_single_step_breakpoints (current_thread
);
3447 unstop_all_lwps (0, event_child
);
3452 debug_printf ("proceeding all threads.\n");
3453 proceed_all_lwps ();
3458 return ignore_event (ourstatus
);
3463 if (event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
3466 = target_waitstatus_to_string (&event_child
->waitstatus
);
3468 debug_printf ("LWP %ld: extended event with waitstatus %s\n",
3469 lwpid_of (get_lwp_thread (event_child
)), str
.c_str ());
3471 if (current_thread
->last_resume_kind
== resume_step
)
3473 if (event_child
->step_range_start
== event_child
->step_range_end
)
3474 debug_printf ("GDB wanted to single-step, reporting event.\n");
3475 else if (!lwp_in_step_range (event_child
))
3476 debug_printf ("Out of step range, reporting event.\n");
3478 if (event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
)
3479 debug_printf ("Stopped by watchpoint.\n");
3480 else if (gdb_breakpoint_here (event_child
->stop_pc
))
3481 debug_printf ("Stopped by GDB breakpoint.\n");
3483 debug_printf ("Hit a non-gdbserver trap event.\n");
3486 /* Alright, we're going to report a stop. */
3488 /* Remove single-step breakpoints. */
3489 if (supports_software_single_step ())
3491 /* Remove single-step breakpoints or not. It it is true, stop all
3492 lwps, so that other threads won't hit the breakpoint in the
3494 int remove_single_step_breakpoints_p
= 0;
3498 remove_single_step_breakpoints_p
3499 = has_single_step_breakpoints (current_thread
);
3503 /* In all-stop, a stop reply cancels all previous resume
3504 requests. Delete all single-step breakpoints. */
3506 find_thread ([&] (thread_info
*thread
) {
3507 if (has_single_step_breakpoints (thread
))
3509 remove_single_step_breakpoints_p
= 1;
3517 if (remove_single_step_breakpoints_p
)
3519 /* If we remove single-step breakpoints from memory, stop all lwps,
3520 so that other threads won't hit the breakpoint in the staled
3522 stop_all_lwps (0, event_child
);
3526 gdb_assert (has_single_step_breakpoints (current_thread
));
3527 delete_single_step_breakpoints (current_thread
);
3531 for_each_thread ([] (thread_info
*thread
){
3532 if (has_single_step_breakpoints (thread
))
3533 delete_single_step_breakpoints (thread
);
3537 unstop_all_lwps (0, event_child
);
3541 if (!stabilizing_threads
)
3543 /* In all-stop, stop all threads. */
3545 stop_all_lwps (0, NULL
);
3547 if (step_over_finished
)
3551 /* If we were doing a step-over, all other threads but
3552 the stepping one had been paused in start_step_over,
3553 with their suspend counts incremented. We don't want
3554 to do a full unstop/unpause, because we're in
3555 all-stop mode (so we want threads stopped), but we
3556 still need to unsuspend the other threads, to
3557 decrement their `suspended' count back. */
3558 unsuspend_all_lwps (event_child
);
3562 /* If we just finished a step-over, then all threads had
3563 been momentarily paused. In all-stop, that's fine,
3564 we want threads stopped by now anyway. In non-stop,
3565 we need to re-resume threads that GDB wanted to be
3567 unstop_all_lwps (1, event_child
);
3571 /* If we're not waiting for a specific LWP, choose an event LWP
3572 from among those that have had events. Giving equal priority
3573 to all LWPs that have had events helps prevent
3575 if (ptid
== minus_one_ptid
)
3577 event_child
->status_pending_p
= 1;
3578 event_child
->status_pending
= w
;
3580 select_event_lwp (&event_child
);
3582 /* current_thread and event_child must stay in sync. */
3583 current_thread
= get_lwp_thread (event_child
);
3585 event_child
->status_pending_p
= 0;
3586 w
= event_child
->status_pending
;
3590 /* Stabilize threads (move out of jump pads). */
3592 target_stabilize_threads ();
3596 /* If we just finished a step-over, then all threads had been
3597 momentarily paused. In all-stop, that's fine, we want
3598 threads stopped by now anyway. In non-stop, we need to
3599 re-resume threads that GDB wanted to be running. */
3600 if (step_over_finished
)
3601 unstop_all_lwps (1, event_child
);
3604 if (event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
3606 /* If the reported event is an exit, fork, vfork or exec, let
3609 /* Break the unreported fork relationship chain. */
3610 if (event_child
->waitstatus
.kind
== TARGET_WAITKIND_FORKED
3611 || event_child
->waitstatus
.kind
== TARGET_WAITKIND_VFORKED
)
3613 event_child
->fork_relative
->fork_relative
= NULL
;
3614 event_child
->fork_relative
= NULL
;
3617 *ourstatus
= event_child
->waitstatus
;
3618 /* Clear the event lwp's waitstatus since we handled it already. */
3619 event_child
->waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
3622 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
3624 /* Now that we've selected our final event LWP, un-adjust its PC if
3625 it was a software breakpoint, and the client doesn't know we can
3626 adjust the breakpoint ourselves. */
3627 if (event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3628 && !cs
.swbreak_feature
)
3630 int decr_pc
= low_decr_pc_after_break ();
3634 struct regcache
*regcache
3635 = get_thread_regcache (current_thread
, 1);
3636 low_set_pc (regcache
, event_child
->stop_pc
+ decr_pc
);
3640 if (WSTOPSIG (w
) == SYSCALL_SIGTRAP
)
3642 get_syscall_trapinfo (event_child
,
3643 &ourstatus
->value
.syscall_number
);
3644 ourstatus
->kind
= event_child
->syscall_state
;
3646 else if (current_thread
->last_resume_kind
== resume_stop
3647 && WSTOPSIG (w
) == SIGSTOP
)
3649 /* A thread that has been requested to stop by GDB with vCont;t,
3650 and it stopped cleanly, so report as SIG0. The use of
3651 SIGSTOP is an implementation detail. */
3652 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
3654 else if (current_thread
->last_resume_kind
== resume_stop
3655 && WSTOPSIG (w
) != SIGSTOP
)
3657 /* A thread that has been requested to stop by GDB with vCont;t,
3658 but, it stopped for other reasons. */
3659 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
3661 else if (ourstatus
->kind
== TARGET_WAITKIND_STOPPED
)
3663 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
3666 gdb_assert (step_over_bkpt
== null_ptid
);
3670 debug_printf ("wait_1 ret = %s, %d, %d\n",
3671 target_pid_to_str (ptid_of (current_thread
)),
3672 ourstatus
->kind
, ourstatus
->value
.sig
);
3676 if (ourstatus
->kind
== TARGET_WAITKIND_EXITED
)
3677 return filter_exit_event (event_child
, ourstatus
);
3679 return ptid_of (current_thread
);
3682 /* Get rid of any pending event in the pipe. */
3684 async_file_flush (void)
3690 ret
= read (linux_event_pipe
[0], &buf
, 1);
3691 while (ret
>= 0 || (ret
== -1 && errno
== EINTR
));
3694 /* Put something in the pipe, so the event loop wakes up. */
3696 async_file_mark (void)
3700 async_file_flush ();
3703 ret
= write (linux_event_pipe
[1], "+", 1);
3704 while (ret
== 0 || (ret
== -1 && errno
== EINTR
));
3706 /* Ignore EAGAIN. If the pipe is full, the event loop will already
3707 be awakened anyway. */
3711 linux_process_target::wait (ptid_t ptid
,
3712 target_waitstatus
*ourstatus
,
3717 /* Flush the async file first. */
3718 if (target_is_async_p ())
3719 async_file_flush ();
3723 event_ptid
= wait_1 (ptid
, ourstatus
, target_options
);
3725 while ((target_options
& TARGET_WNOHANG
) == 0
3726 && event_ptid
== null_ptid
3727 && ourstatus
->kind
== TARGET_WAITKIND_IGNORE
);
3729 /* If at least one stop was reported, there may be more. A single
3730 SIGCHLD can signal more than one child stop. */
3731 if (target_is_async_p ()
3732 && (target_options
& TARGET_WNOHANG
) != 0
3733 && event_ptid
!= null_ptid
)
3739 /* Send a signal to an LWP. */
3742 kill_lwp (unsigned long lwpid
, int signo
)
3747 ret
= syscall (__NR_tkill
, lwpid
, signo
);
3748 if (errno
== ENOSYS
)
3750 /* If tkill fails, then we are not using nptl threads, a
3751 configuration we no longer support. */
3752 perror_with_name (("tkill"));
3758 linux_stop_lwp (struct lwp_info
*lwp
)
3764 send_sigstop (struct lwp_info
*lwp
)
3768 pid
= lwpid_of (get_lwp_thread (lwp
));
3770 /* If we already have a pending stop signal for this process, don't
3772 if (lwp
->stop_expected
)
3775 debug_printf ("Have pending sigstop for lwp %d\n", pid
);
3781 debug_printf ("Sending sigstop to lwp %d\n", pid
);
3783 lwp
->stop_expected
= 1;
3784 kill_lwp (pid
, SIGSTOP
);
3788 send_sigstop (thread_info
*thread
, lwp_info
*except
)
3790 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3792 /* Ignore EXCEPT. */
3802 /* Increment the suspend count of an LWP, and stop it, if not stopped
3805 suspend_and_send_sigstop (thread_info
*thread
, lwp_info
*except
)
3807 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3809 /* Ignore EXCEPT. */
3813 lwp_suspended_inc (lwp
);
3815 send_sigstop (thread
, except
);
3819 mark_lwp_dead (struct lwp_info
*lwp
, int wstat
)
3821 /* Store the exit status for later. */
3822 lwp
->status_pending_p
= 1;
3823 lwp
->status_pending
= wstat
;
3825 /* Store in waitstatus as well, as there's nothing else to process
3827 if (WIFEXITED (wstat
))
3829 lwp
->waitstatus
.kind
= TARGET_WAITKIND_EXITED
;
3830 lwp
->waitstatus
.value
.integer
= WEXITSTATUS (wstat
);
3832 else if (WIFSIGNALED (wstat
))
3834 lwp
->waitstatus
.kind
= TARGET_WAITKIND_SIGNALLED
;
3835 lwp
->waitstatus
.value
.sig
= gdb_signal_from_host (WTERMSIG (wstat
));
3838 /* Prevent trying to stop it. */
3841 /* No further stops are expected from a dead lwp. */
3842 lwp
->stop_expected
= 0;
3845 /* Return true if LWP has exited already, and has a pending exit event
3846 to report to GDB. */
3849 lwp_is_marked_dead (struct lwp_info
*lwp
)
3851 return (lwp
->status_pending_p
3852 && (WIFEXITED (lwp
->status_pending
)
3853 || WIFSIGNALED (lwp
->status_pending
)));
3857 linux_process_target::wait_for_sigstop ()
3859 struct thread_info
*saved_thread
;
3864 saved_thread
= current_thread
;
3865 if (saved_thread
!= NULL
)
3866 saved_tid
= saved_thread
->id
;
3868 saved_tid
= null_ptid
; /* avoid bogus unused warning */
3871 debug_printf ("wait_for_sigstop: pulling events\n");
3873 /* Passing NULL_PTID as filter indicates we want all events to be
3874 left pending. Eventually this returns when there are no
3875 unwaited-for children left. */
3876 ret
= wait_for_event_filtered (minus_one_ptid
, null_ptid
, &wstat
, __WALL
);
3877 gdb_assert (ret
== -1);
3879 if (saved_thread
== NULL
|| mythread_alive (saved_tid
))
3880 current_thread
= saved_thread
;
3884 debug_printf ("Previously current thread died.\n");
3886 /* We can't change the current inferior behind GDB's back,
3887 otherwise, a subsequent command may apply to the wrong
3889 current_thread
= NULL
;
3894 linux_process_target::stuck_in_jump_pad (thread_info
*thread
)
3896 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3898 if (lwp
->suspended
!= 0)
3900 internal_error (__FILE__
, __LINE__
,
3901 "LWP %ld is suspended, suspended=%d\n",
3902 lwpid_of (thread
), lwp
->suspended
);
3904 gdb_assert (lwp
->stopped
);
3906 /* Allow debugging the jump pad, gdb_collect, etc.. */
3907 return (supports_fast_tracepoints ()
3908 && agent_loaded_p ()
3909 && (gdb_breakpoint_here (lwp
->stop_pc
)
3910 || lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
3911 || thread
->last_resume_kind
== resume_step
)
3912 && (linux_fast_tracepoint_collecting (lwp
, NULL
)
3913 != fast_tpoint_collect_result::not_collecting
));
3917 linux_process_target::move_out_of_jump_pad (thread_info
*thread
)
3919 struct thread_info
*saved_thread
;
3920 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3923 if (lwp
->suspended
!= 0)
3925 internal_error (__FILE__
, __LINE__
,
3926 "LWP %ld is suspended, suspended=%d\n",
3927 lwpid_of (thread
), lwp
->suspended
);
3929 gdb_assert (lwp
->stopped
);
3931 /* For gdb_breakpoint_here. */
3932 saved_thread
= current_thread
;
3933 current_thread
= thread
;
3935 wstat
= lwp
->status_pending_p
? &lwp
->status_pending
: NULL
;
3937 /* Allow debugging the jump pad, gdb_collect, etc. */
3938 if (!gdb_breakpoint_here (lwp
->stop_pc
)
3939 && lwp
->stop_reason
!= TARGET_STOPPED_BY_WATCHPOINT
3940 && thread
->last_resume_kind
!= resume_step
3941 && maybe_move_out_of_jump_pad (lwp
, wstat
))
3944 debug_printf ("LWP %ld needs stabilizing (in jump pad)\n",
3949 lwp
->status_pending_p
= 0;
3950 enqueue_one_deferred_signal (lwp
, wstat
);
3953 debug_printf ("Signal %d for LWP %ld deferred "
3955 WSTOPSIG (*wstat
), lwpid_of (thread
));
3958 resume_one_lwp (lwp
, 0, 0, NULL
);
3961 lwp_suspended_inc (lwp
);
3963 current_thread
= saved_thread
;
3967 lwp_running (thread_info
*thread
)
3969 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3971 if (lwp_is_marked_dead (lwp
))
3974 return !lwp
->stopped
;
3978 linux_process_target::stop_all_lwps (int suspend
, lwp_info
*except
)
3980 /* Should not be called recursively. */
3981 gdb_assert (stopping_threads
== NOT_STOPPING_THREADS
);
3986 debug_printf ("stop_all_lwps (%s, except=%s)\n",
3987 suspend
? "stop-and-suspend" : "stop",
3989 ? target_pid_to_str (ptid_of (get_lwp_thread (except
)))
3993 stopping_threads
= (suspend
3994 ? STOPPING_AND_SUSPENDING_THREADS
3995 : STOPPING_THREADS
);
3998 for_each_thread ([&] (thread_info
*thread
)
4000 suspend_and_send_sigstop (thread
, except
);
4003 for_each_thread ([&] (thread_info
*thread
)
4005 send_sigstop (thread
, except
);
4008 wait_for_sigstop ();
4009 stopping_threads
= NOT_STOPPING_THREADS
;
4013 debug_printf ("stop_all_lwps done, setting stopping_threads "
4014 "back to !stopping\n");
4019 /* Enqueue one signal in the chain of signals which need to be
4020 delivered to this process on next resume. */
4023 enqueue_pending_signal (struct lwp_info
*lwp
, int signal
, siginfo_t
*info
)
4025 lwp
->pending_signals
.emplace_back (signal
);
4026 if (info
== nullptr)
4027 memset (&lwp
->pending_signals
.back ().info
, 0, sizeof (siginfo_t
));
4029 lwp
->pending_signals
.back ().info
= *info
;
4033 linux_process_target::install_software_single_step_breakpoints (lwp_info
*lwp
)
4035 struct thread_info
*thread
= get_lwp_thread (lwp
);
4036 struct regcache
*regcache
= get_thread_regcache (thread
, 1);
4038 scoped_restore save_current_thread
= make_scoped_restore (¤t_thread
);
4040 current_thread
= thread
;
4041 std::vector
<CORE_ADDR
> next_pcs
= low_get_next_pcs (regcache
);
4043 for (CORE_ADDR pc
: next_pcs
)
4044 set_single_step_breakpoint (pc
, current_ptid
);
4048 linux_process_target::single_step (lwp_info
* lwp
)
4052 if (supports_hardware_single_step ())
4056 else if (supports_software_single_step ())
4058 install_software_single_step_breakpoints (lwp
);
4064 debug_printf ("stepping is not implemented on this target");
4070 /* The signal can be delivered to the inferior if we are not trying to
4071 finish a fast tracepoint collect. Since signal can be delivered in
4072 the step-over, the program may go to signal handler and trap again
4073 after return from the signal handler. We can live with the spurious
4077 lwp_signal_can_be_delivered (struct lwp_info
*lwp
)
4079 return (lwp
->collecting_fast_tracepoint
4080 == fast_tpoint_collect_result::not_collecting
);
4084 linux_process_target::resume_one_lwp_throw (lwp_info
*lwp
, int step
,
4085 int signal
, siginfo_t
*info
)
4087 struct thread_info
*thread
= get_lwp_thread (lwp
);
4088 struct thread_info
*saved_thread
;
4090 struct process_info
*proc
= get_thread_process (thread
);
4092 /* Note that target description may not be initialised
4093 (proc->tdesc == NULL) at this point because the program hasn't
4094 stopped at the first instruction yet. It means GDBserver skips
4095 the extra traps from the wrapper program (see option --wrapper).
4096 Code in this function that requires register access should be
4097 guarded by proc->tdesc == NULL or something else. */
4099 if (lwp
->stopped
== 0)
4102 gdb_assert (lwp
->waitstatus
.kind
== TARGET_WAITKIND_IGNORE
);
4104 fast_tpoint_collect_result fast_tp_collecting
4105 = lwp
->collecting_fast_tracepoint
;
4107 gdb_assert (!stabilizing_threads
4108 || (fast_tp_collecting
4109 != fast_tpoint_collect_result::not_collecting
));
4111 /* Cancel actions that rely on GDB not changing the PC (e.g., the
4112 user used the "jump" command, or "set $pc = foo"). */
4113 if (thread
->while_stepping
!= NULL
&& lwp
->stop_pc
!= get_pc (lwp
))
4115 /* Collecting 'while-stepping' actions doesn't make sense
4117 release_while_stepping_state_list (thread
);
4120 /* If we have pending signals or status, and a new signal, enqueue the
4121 signal. Also enqueue the signal if it can't be delivered to the
4122 inferior right now. */
4124 && (lwp
->status_pending_p
4125 || !lwp
->pending_signals
.empty ()
4126 || !lwp_signal_can_be_delivered (lwp
)))
4128 enqueue_pending_signal (lwp
, signal
, info
);
4130 /* Postpone any pending signal. It was enqueued above. */
4134 if (lwp
->status_pending_p
)
4137 debug_printf ("Not resuming lwp %ld (%s, stop %s);"
4138 " has pending status\n",
4139 lwpid_of (thread
), step
? "step" : "continue",
4140 lwp
->stop_expected
? "expected" : "not expected");
4144 saved_thread
= current_thread
;
4145 current_thread
= thread
;
4147 /* This bit needs some thinking about. If we get a signal that
4148 we must report while a single-step reinsert is still pending,
4149 we often end up resuming the thread. It might be better to
4150 (ew) allow a stack of pending events; then we could be sure that
4151 the reinsert happened right away and not lose any signals.
4153 Making this stack would also shrink the window in which breakpoints are
4154 uninserted (see comment in linux_wait_for_lwp) but not enough for
4155 complete correctness, so it won't solve that problem. It may be
4156 worthwhile just to solve this one, however. */
4157 if (lwp
->bp_reinsert
!= 0)
4160 debug_printf (" pending reinsert at 0x%s\n",
4161 paddress (lwp
->bp_reinsert
));
4163 if (supports_hardware_single_step ())
4165 if (fast_tp_collecting
== fast_tpoint_collect_result::not_collecting
)
4168 warning ("BAD - reinserting but not stepping.");
4170 warning ("BAD - reinserting and suspended(%d).",
4175 step
= maybe_hw_step (thread
);
4178 if (fast_tp_collecting
== fast_tpoint_collect_result::before_insn
)
4181 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
4182 " (exit-jump-pad-bkpt)\n",
4185 else if (fast_tp_collecting
== fast_tpoint_collect_result::at_insn
)
4188 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
4189 " single-stepping\n",
4192 if (supports_hardware_single_step ())
4196 internal_error (__FILE__
, __LINE__
,
4197 "moving out of jump pad single-stepping"
4198 " not implemented on this target");
4202 /* If we have while-stepping actions in this thread set it stepping.
4203 If we have a signal to deliver, it may or may not be set to
4204 SIG_IGN, we don't know. Assume so, and allow collecting
4205 while-stepping into a signal handler. A possible smart thing to
4206 do would be to set an internal breakpoint at the signal return
4207 address, continue, and carry on catching this while-stepping
4208 action only when that breakpoint is hit. A future
4210 if (thread
->while_stepping
!= NULL
)
4213 debug_printf ("lwp %ld has a while-stepping action -> forcing step.\n",
4216 step
= single_step (lwp
);
4219 if (proc
->tdesc
!= NULL
&& low_supports_breakpoints ())
4221 struct regcache
*regcache
= get_thread_regcache (current_thread
, 1);
4223 lwp
->stop_pc
= low_get_pc (regcache
);
4227 debug_printf (" %s from pc 0x%lx\n", step
? "step" : "continue",
4228 (long) lwp
->stop_pc
);
4232 /* If we have pending signals, consume one if it can be delivered to
4234 if (!lwp
->pending_signals
.empty () && lwp_signal_can_be_delivered (lwp
))
4236 const pending_signal
&p_sig
= lwp
->pending_signals
.front ();
4238 signal
= p_sig
.signal
;
4239 if (p_sig
.info
.si_signo
!= 0)
4240 ptrace (PTRACE_SETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
4243 lwp
->pending_signals
.pop_front ();
4247 debug_printf ("Resuming lwp %ld (%s, signal %d, stop %s)\n",
4248 lwpid_of (thread
), step
? "step" : "continue", signal
,
4249 lwp
->stop_expected
? "expected" : "not expected");
4251 low_prepare_to_resume (lwp
);
4253 regcache_invalidate_thread (thread
);
4255 lwp
->stepping
= step
;
4257 ptrace_request
= PTRACE_SINGLESTEP
;
4258 else if (gdb_catching_syscalls_p (lwp
))
4259 ptrace_request
= PTRACE_SYSCALL
;
4261 ptrace_request
= PTRACE_CONT
;
4262 ptrace (ptrace_request
,
4264 (PTRACE_TYPE_ARG3
) 0,
4265 /* Coerce to a uintptr_t first to avoid potential gcc warning
4266 of coercing an 8 byte integer to a 4 byte pointer. */
4267 (PTRACE_TYPE_ARG4
) (uintptr_t) signal
);
4269 current_thread
= saved_thread
;
4271 perror_with_name ("resuming thread");
4273 /* Successfully resumed. Clear state that no longer makes sense,
4274 and mark the LWP as running. Must not do this before resuming
4275 otherwise if that fails other code will be confused. E.g., we'd
4276 later try to stop the LWP and hang forever waiting for a stop
4277 status. Note that we must not throw after this is cleared,
4278 otherwise handle_zombie_lwp_error would get confused. */
4280 lwp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
4284 linux_process_target::low_prepare_to_resume (lwp_info
*lwp
)
4289 /* Called when we try to resume a stopped LWP and that errors out. If
4290 the LWP is no longer in ptrace-stopped state (meaning it's zombie,
4291 or about to become), discard the error, clear any pending status
4292 the LWP may have, and return true (we'll collect the exit status
4293 soon enough). Otherwise, return false. */
4296 check_ptrace_stopped_lwp_gone (struct lwp_info
*lp
)
4298 struct thread_info
*thread
= get_lwp_thread (lp
);
4300 /* If we get an error after resuming the LWP successfully, we'd
4301 confuse !T state for the LWP being gone. */
4302 gdb_assert (lp
->stopped
);
4304 /* We can't just check whether the LWP is in 'Z (Zombie)' state,
4305 because even if ptrace failed with ESRCH, the tracee may be "not
4306 yet fully dead", but already refusing ptrace requests. In that
4307 case the tracee has 'R (Running)' state for a little bit
4308 (observed in Linux 3.18). See also the note on ESRCH in the
4309 ptrace(2) man page. Instead, check whether the LWP has any state
4310 other than ptrace-stopped. */
4312 /* Don't assume anything if /proc/PID/status can't be read. */
4313 if (linux_proc_pid_is_trace_stopped_nowarn (lwpid_of (thread
)) == 0)
4315 lp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
4316 lp
->status_pending_p
= 0;
4323 linux_process_target::resume_one_lwp (lwp_info
*lwp
, int step
, int signal
,
4328 resume_one_lwp_throw (lwp
, step
, signal
, info
);
4330 catch (const gdb_exception_error
&ex
)
4332 if (!check_ptrace_stopped_lwp_gone (lwp
))
4337 /* This function is called once per thread via for_each_thread.
4338 We look up which resume request applies to THREAD and mark it with a
4339 pointer to the appropriate resume request.
4341 This algorithm is O(threads * resume elements), but resume elements
4342 is small (and will remain small at least until GDB supports thread
4346 linux_set_resume_request (thread_info
*thread
, thread_resume
*resume
, size_t n
)
4348 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4350 for (int ndx
= 0; ndx
< n
; ndx
++)
4352 ptid_t ptid
= resume
[ndx
].thread
;
4353 if (ptid
== minus_one_ptid
4354 || ptid
== thread
->id
4355 /* Handle both 'pPID' and 'pPID.-1' as meaning 'all threads
4357 || (ptid
.pid () == pid_of (thread
)
4359 || ptid
.lwp () == -1)))
4361 if (resume
[ndx
].kind
== resume_stop
4362 && thread
->last_resume_kind
== resume_stop
)
4365 debug_printf ("already %s LWP %ld at GDB's request\n",
4366 (thread
->last_status
.kind
4367 == TARGET_WAITKIND_STOPPED
)
4375 /* Ignore (wildcard) resume requests for already-resumed
4377 if (resume
[ndx
].kind
!= resume_stop
4378 && thread
->last_resume_kind
!= resume_stop
)
4381 debug_printf ("already %s LWP %ld at GDB's request\n",
4382 (thread
->last_resume_kind
4390 /* Don't let wildcard resumes resume fork children that GDB
4391 does not yet know are new fork children. */
4392 if (lwp
->fork_relative
!= NULL
)
4394 struct lwp_info
*rel
= lwp
->fork_relative
;
4396 if (rel
->status_pending_p
4397 && (rel
->waitstatus
.kind
== TARGET_WAITKIND_FORKED
4398 || rel
->waitstatus
.kind
== TARGET_WAITKIND_VFORKED
))
4401 debug_printf ("not resuming LWP %ld: has queued stop reply\n",
4407 /* If the thread has a pending event that has already been
4408 reported to GDBserver core, but GDB has not pulled the
4409 event out of the vStopped queue yet, likewise, ignore the
4410 (wildcard) resume request. */
4411 if (in_queued_stop_replies (thread
->id
))
4414 debug_printf ("not resuming LWP %ld: has queued stop reply\n",
4419 lwp
->resume
= &resume
[ndx
];
4420 thread
->last_resume_kind
= lwp
->resume
->kind
;
4422 lwp
->step_range_start
= lwp
->resume
->step_range_start
;
4423 lwp
->step_range_end
= lwp
->resume
->step_range_end
;
4425 /* If we had a deferred signal to report, dequeue one now.
4426 This can happen if LWP gets more than one signal while
4427 trying to get out of a jump pad. */
4429 && !lwp
->status_pending_p
4430 && dequeue_one_deferred_signal (lwp
, &lwp
->status_pending
))
4432 lwp
->status_pending_p
= 1;
4435 debug_printf ("Dequeueing deferred signal %d for LWP %ld, "
4436 "leaving status pending.\n",
4437 WSTOPSIG (lwp
->status_pending
),
4445 /* No resume action for this thread. */
4450 linux_process_target::resume_status_pending (thread_info
*thread
)
4452 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4454 /* LWPs which will not be resumed are not interesting, because
4455 we might not wait for them next time through linux_wait. */
4456 if (lwp
->resume
== NULL
)
4459 return thread_still_has_status_pending (thread
);
4463 linux_process_target::thread_needs_step_over (thread_info
*thread
)
4465 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4466 struct thread_info
*saved_thread
;
4468 struct process_info
*proc
= get_thread_process (thread
);
4470 /* GDBserver is skipping the extra traps from the wrapper program,
4471 don't have to do step over. */
4472 if (proc
->tdesc
== NULL
)
4475 /* LWPs which will not be resumed are not interesting, because we
4476 might not wait for them next time through linux_wait. */
4481 debug_printf ("Need step over [LWP %ld]? Ignoring, not stopped\n",
4486 if (thread
->last_resume_kind
== resume_stop
)
4489 debug_printf ("Need step over [LWP %ld]? Ignoring, should remain"
4495 gdb_assert (lwp
->suspended
>= 0);
4500 debug_printf ("Need step over [LWP %ld]? Ignoring, suspended\n",
4505 if (lwp
->status_pending_p
)
4508 debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
4514 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
4518 /* If the PC has changed since we stopped, then don't do anything,
4519 and let the breakpoint/tracepoint be hit. This happens if, for
4520 instance, GDB handled the decr_pc_after_break subtraction itself,
4521 GDB is OOL stepping this thread, or the user has issued a "jump"
4522 command, or poked thread's registers herself. */
4523 if (pc
!= lwp
->stop_pc
)
4526 debug_printf ("Need step over [LWP %ld]? Cancelling, PC was changed. "
4527 "Old stop_pc was 0x%s, PC is now 0x%s\n",
4529 paddress (lwp
->stop_pc
), paddress (pc
));
4533 /* On software single step target, resume the inferior with signal
4534 rather than stepping over. */
4535 if (supports_software_single_step ()
4536 && !lwp
->pending_signals
.empty ()
4537 && lwp_signal_can_be_delivered (lwp
))
4540 debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
4547 saved_thread
= current_thread
;
4548 current_thread
= thread
;
4550 /* We can only step over breakpoints we know about. */
4551 if (breakpoint_here (pc
) || fast_tracepoint_jump_here (pc
))
4553 /* Don't step over a breakpoint that GDB expects to hit
4554 though. If the condition is being evaluated on the target's side
4555 and it evaluate to false, step over this breakpoint as well. */
4556 if (gdb_breakpoint_here (pc
)
4557 && gdb_condition_true_at_breakpoint (pc
)
4558 && gdb_no_commands_at_breakpoint (pc
))
4561 debug_printf ("Need step over [LWP %ld]? yes, but found"
4562 " GDB breakpoint at 0x%s; skipping step over\n",
4563 lwpid_of (thread
), paddress (pc
));
4565 current_thread
= saved_thread
;
4571 debug_printf ("Need step over [LWP %ld]? yes, "
4572 "found breakpoint at 0x%s\n",
4573 lwpid_of (thread
), paddress (pc
));
4575 /* We've found an lwp that needs stepping over --- return 1 so
4576 that find_thread stops looking. */
4577 current_thread
= saved_thread
;
4583 current_thread
= saved_thread
;
4586 debug_printf ("Need step over [LWP %ld]? No, no breakpoint found"
4588 lwpid_of (thread
), paddress (pc
));
4594 linux_process_target::start_step_over (lwp_info
*lwp
)
4596 struct thread_info
*thread
= get_lwp_thread (lwp
);
4597 struct thread_info
*saved_thread
;
4602 debug_printf ("Starting step-over on LWP %ld. Stopping all threads\n",
4605 stop_all_lwps (1, lwp
);
4607 if (lwp
->suspended
!= 0)
4609 internal_error (__FILE__
, __LINE__
,
4610 "LWP %ld suspended=%d\n", lwpid_of (thread
),
4615 debug_printf ("Done stopping all threads for step-over.\n");
4617 /* Note, we should always reach here with an already adjusted PC,
4618 either by GDB (if we're resuming due to GDB's request), or by our
4619 caller, if we just finished handling an internal breakpoint GDB
4620 shouldn't care about. */
4623 saved_thread
= current_thread
;
4624 current_thread
= thread
;
4626 lwp
->bp_reinsert
= pc
;
4627 uninsert_breakpoints_at (pc
);
4628 uninsert_fast_tracepoint_jumps_at (pc
);
4630 step
= single_step (lwp
);
4632 current_thread
= saved_thread
;
4634 resume_one_lwp (lwp
, step
, 0, NULL
);
4636 /* Require next event from this LWP. */
4637 step_over_bkpt
= thread
->id
;
4641 linux_process_target::finish_step_over (lwp_info
*lwp
)
4643 if (lwp
->bp_reinsert
!= 0)
4645 struct thread_info
*saved_thread
= current_thread
;
4648 debug_printf ("Finished step over.\n");
4650 current_thread
= get_lwp_thread (lwp
);
4652 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
4653 may be no breakpoint to reinsert there by now. */
4654 reinsert_breakpoints_at (lwp
->bp_reinsert
);
4655 reinsert_fast_tracepoint_jumps_at (lwp
->bp_reinsert
);
4657 lwp
->bp_reinsert
= 0;
4659 /* Delete any single-step breakpoints. No longer needed. We
4660 don't have to worry about other threads hitting this trap,
4661 and later not being able to explain it, because we were
4662 stepping over a breakpoint, and we hold all threads but
4663 LWP stopped while doing that. */
4664 if (!supports_hardware_single_step ())
4666 gdb_assert (has_single_step_breakpoints (current_thread
));
4667 delete_single_step_breakpoints (current_thread
);
4670 step_over_bkpt
= null_ptid
;
4671 current_thread
= saved_thread
;
4679 linux_process_target::complete_ongoing_step_over ()
4681 if (step_over_bkpt
!= null_ptid
)
4683 struct lwp_info
*lwp
;
4688 debug_printf ("detach: step over in progress, finish it first\n");
4690 /* Passing NULL_PTID as filter indicates we want all events to
4691 be left pending. Eventually this returns when there are no
4692 unwaited-for children left. */
4693 ret
= wait_for_event_filtered (minus_one_ptid
, null_ptid
, &wstat
,
4695 gdb_assert (ret
== -1);
4697 lwp
= find_lwp_pid (step_over_bkpt
);
4699 finish_step_over (lwp
);
4700 step_over_bkpt
= null_ptid
;
4701 unsuspend_all_lwps (lwp
);
4706 linux_process_target::resume_one_thread (thread_info
*thread
,
4707 bool leave_all_stopped
)
4709 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4712 if (lwp
->resume
== NULL
)
4715 if (lwp
->resume
->kind
== resume_stop
)
4718 debug_printf ("resume_stop request for LWP %ld\n", lwpid_of (thread
));
4723 debug_printf ("stopping LWP %ld\n", lwpid_of (thread
));
4725 /* Stop the thread, and wait for the event asynchronously,
4726 through the event loop. */
4732 debug_printf ("already stopped LWP %ld\n",
4735 /* The LWP may have been stopped in an internal event that
4736 was not meant to be notified back to GDB (e.g., gdbserver
4737 breakpoint), so we should be reporting a stop event in
4740 /* If the thread already has a pending SIGSTOP, this is a
4741 no-op. Otherwise, something later will presumably resume
4742 the thread and this will cause it to cancel any pending
4743 operation, due to last_resume_kind == resume_stop. If
4744 the thread already has a pending status to report, we
4745 will still report it the next time we wait - see
4746 status_pending_p_callback. */
4748 /* If we already have a pending signal to report, then
4749 there's no need to queue a SIGSTOP, as this means we're
4750 midway through moving the LWP out of the jumppad, and we
4751 will report the pending signal as soon as that is
4753 if (lwp
->pending_signals_to_report
.empty ())
4757 /* For stop requests, we're done. */
4759 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
4763 /* If this thread which is about to be resumed has a pending status,
4764 then don't resume it - we can just report the pending status.
4765 Likewise if it is suspended, because e.g., another thread is
4766 stepping past a breakpoint. Make sure to queue any signals that
4767 would otherwise be sent. In all-stop mode, we do this decision
4768 based on if *any* thread has a pending status. If there's a
4769 thread that needs the step-over-breakpoint dance, then don't
4770 resume any other thread but that particular one. */
4771 leave_pending
= (lwp
->suspended
4772 || lwp
->status_pending_p
4773 || leave_all_stopped
);
4775 /* If we have a new signal, enqueue the signal. */
4776 if (lwp
->resume
->sig
!= 0)
4778 siginfo_t info
, *info_p
;
4780 /* If this is the same signal we were previously stopped by,
4781 make sure to queue its siginfo. */
4782 if (WIFSTOPPED (lwp
->last_status
)
4783 && WSTOPSIG (lwp
->last_status
) == lwp
->resume
->sig
4784 && ptrace (PTRACE_GETSIGINFO
, lwpid_of (thread
),
4785 (PTRACE_TYPE_ARG3
) 0, &info
) == 0)
4790 enqueue_pending_signal (lwp
, lwp
->resume
->sig
, info_p
);
4796 debug_printf ("resuming LWP %ld\n", lwpid_of (thread
));
4798 proceed_one_lwp (thread
, NULL
);
4803 debug_printf ("leaving LWP %ld stopped\n", lwpid_of (thread
));
4806 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
4811 linux_process_target::resume (thread_resume
*resume_info
, size_t n
)
4813 struct thread_info
*need_step_over
= NULL
;
4818 debug_printf ("linux_resume:\n");
4821 for_each_thread ([&] (thread_info
*thread
)
4823 linux_set_resume_request (thread
, resume_info
, n
);
4826 /* If there is a thread which would otherwise be resumed, which has
4827 a pending status, then don't resume any threads - we can just
4828 report the pending status. Make sure to queue any signals that
4829 would otherwise be sent. In non-stop mode, we'll apply this
4830 logic to each thread individually. We consume all pending events
4831 before considering to start a step-over (in all-stop). */
4832 bool any_pending
= false;
4834 any_pending
= find_thread ([this] (thread_info
*thread
)
4836 return resume_status_pending (thread
);
4839 /* If there is a thread which would otherwise be resumed, which is
4840 stopped at a breakpoint that needs stepping over, then don't
4841 resume any threads - have it step over the breakpoint with all
4842 other threads stopped, then resume all threads again. Make sure
4843 to queue any signals that would otherwise be delivered or
4845 if (!any_pending
&& low_supports_breakpoints ())
4846 need_step_over
= find_thread ([this] (thread_info
*thread
)
4848 return thread_needs_step_over (thread
);
4851 bool leave_all_stopped
= (need_step_over
!= NULL
|| any_pending
);
4855 if (need_step_over
!= NULL
)
4856 debug_printf ("Not resuming all, need step over\n");
4857 else if (any_pending
)
4858 debug_printf ("Not resuming, all-stop and found "
4859 "an LWP with pending status\n");
4861 debug_printf ("Resuming, no pending status or step over needed\n");
4864 /* Even if we're leaving threads stopped, queue all signals we'd
4865 otherwise deliver. */
4866 for_each_thread ([&] (thread_info
*thread
)
4868 resume_one_thread (thread
, leave_all_stopped
);
4872 start_step_over (get_thread_lwp (need_step_over
));
4876 debug_printf ("linux_resume done\n");
4880 /* We may have events that were pending that can/should be sent to
4881 the client now. Trigger a linux_wait call. */
4882 if (target_is_async_p ())
4887 linux_process_target::proceed_one_lwp (thread_info
*thread
, lwp_info
*except
)
4889 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4896 debug_printf ("proceed_one_lwp: lwp %ld\n", lwpid_of (thread
));
4901 debug_printf (" LWP %ld already running\n", lwpid_of (thread
));
4905 if (thread
->last_resume_kind
== resume_stop
4906 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
4909 debug_printf (" client wants LWP to remain %ld stopped\n",
4914 if (lwp
->status_pending_p
)
4917 debug_printf (" LWP %ld has pending status, leaving stopped\n",
4922 gdb_assert (lwp
->suspended
>= 0);
4927 debug_printf (" LWP %ld is suspended\n", lwpid_of (thread
));
4931 if (thread
->last_resume_kind
== resume_stop
4932 && lwp
->pending_signals_to_report
.empty ()
4933 && (lwp
->collecting_fast_tracepoint
4934 == fast_tpoint_collect_result::not_collecting
))
4936 /* We haven't reported this LWP as stopped yet (otherwise, the
4937 last_status.kind check above would catch it, and we wouldn't
4938 reach here. This LWP may have been momentarily paused by a
4939 stop_all_lwps call while handling for example, another LWP's
4940 step-over. In that case, the pending expected SIGSTOP signal
4941 that was queued at vCont;t handling time will have already
4942 been consumed by wait_for_sigstop, and so we need to requeue
4943 another one here. Note that if the LWP already has a SIGSTOP
4944 pending, this is a no-op. */
4947 debug_printf ("Client wants LWP %ld to stop. "
4948 "Making sure it has a SIGSTOP pending\n",
4954 if (thread
->last_resume_kind
== resume_step
)
4957 debug_printf (" stepping LWP %ld, client wants it stepping\n",
4960 /* If resume_step is requested by GDB, install single-step
4961 breakpoints when the thread is about to be actually resumed if
4962 the single-step breakpoints weren't removed. */
4963 if (supports_software_single_step ()
4964 && !has_single_step_breakpoints (thread
))
4965 install_software_single_step_breakpoints (lwp
);
4967 step
= maybe_hw_step (thread
);
4969 else if (lwp
->bp_reinsert
!= 0)
4972 debug_printf (" stepping LWP %ld, reinsert set\n",
4975 step
= maybe_hw_step (thread
);
4980 resume_one_lwp (lwp
, step
, 0, NULL
);
4984 linux_process_target::unsuspend_and_proceed_one_lwp (thread_info
*thread
,
4987 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4992 lwp_suspended_decr (lwp
);
4994 proceed_one_lwp (thread
, except
);
4998 linux_process_target::proceed_all_lwps ()
5000 struct thread_info
*need_step_over
;
5002 /* If there is a thread which would otherwise be resumed, which is
5003 stopped at a breakpoint that needs stepping over, then don't
5004 resume any threads - have it step over the breakpoint with all
5005 other threads stopped, then resume all threads again. */
5007 if (low_supports_breakpoints ())
5009 need_step_over
= find_thread ([this] (thread_info
*thread
)
5011 return thread_needs_step_over (thread
);
5014 if (need_step_over
!= NULL
)
5017 debug_printf ("proceed_all_lwps: found "
5018 "thread %ld needing a step-over\n",
5019 lwpid_of (need_step_over
));
5021 start_step_over (get_thread_lwp (need_step_over
));
5027 debug_printf ("Proceeding, no step-over needed\n");
5029 for_each_thread ([this] (thread_info
*thread
)
5031 proceed_one_lwp (thread
, NULL
);
5036 linux_process_target::unstop_all_lwps (int unsuspend
, lwp_info
*except
)
5042 debug_printf ("unstopping all lwps, except=(LWP %ld)\n",
5043 lwpid_of (get_lwp_thread (except
)));
5045 debug_printf ("unstopping all lwps\n");
5049 for_each_thread ([&] (thread_info
*thread
)
5051 unsuspend_and_proceed_one_lwp (thread
, except
);
5054 for_each_thread ([&] (thread_info
*thread
)
5056 proceed_one_lwp (thread
, except
);
5061 debug_printf ("unstop_all_lwps done\n");
5067 #ifdef HAVE_LINUX_REGSETS
5069 #define use_linux_regsets 1
5071 /* Returns true if REGSET has been disabled. */
5074 regset_disabled (struct regsets_info
*info
, struct regset_info
*regset
)
5076 return (info
->disabled_regsets
!= NULL
5077 && info
->disabled_regsets
[regset
- info
->regsets
]);
5080 /* Disable REGSET. */
5083 disable_regset (struct regsets_info
*info
, struct regset_info
*regset
)
5087 dr_offset
= regset
- info
->regsets
;
5088 if (info
->disabled_regsets
== NULL
)
5089 info
->disabled_regsets
= (char *) xcalloc (1, info
->num_regsets
);
5090 info
->disabled_regsets
[dr_offset
] = 1;
5094 regsets_fetch_inferior_registers (struct regsets_info
*regsets_info
,
5095 struct regcache
*regcache
)
5097 struct regset_info
*regset
;
5098 int saw_general_regs
= 0;
5102 pid
= lwpid_of (current_thread
);
5103 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
5108 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
))
5111 buf
= xmalloc (regset
->size
);
5113 nt_type
= regset
->nt_type
;
5117 iov
.iov_len
= regset
->size
;
5118 data
= (void *) &iov
;
5124 res
= ptrace (regset
->get_request
, pid
,
5125 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5127 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
5132 || (errno
== EINVAL
&& regset
->type
== OPTIONAL_REGS
))
5134 /* If we get EIO on a regset, or an EINVAL and the regset is
5135 optional, do not try it again for this process mode. */
5136 disable_regset (regsets_info
, regset
);
5138 else if (errno
== ENODATA
)
5140 /* ENODATA may be returned if the regset is currently
5141 not "active". This can happen in normal operation,
5142 so suppress the warning in this case. */
5144 else if (errno
== ESRCH
)
5146 /* At this point, ESRCH should mean the process is
5147 already gone, in which case we simply ignore attempts
5148 to read its registers. */
5153 sprintf (s
, "ptrace(regsets_fetch_inferior_registers) PID=%d",
5160 if (regset
->type
== GENERAL_REGS
)
5161 saw_general_regs
= 1;
5162 regset
->store_function (regcache
, buf
);
5166 if (saw_general_regs
)
5173 regsets_store_inferior_registers (struct regsets_info
*regsets_info
,
5174 struct regcache
*regcache
)
5176 struct regset_info
*regset
;
5177 int saw_general_regs
= 0;
5181 pid
= lwpid_of (current_thread
);
5182 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
5187 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
)
5188 || regset
->fill_function
== NULL
)
5191 buf
= xmalloc (regset
->size
);
5193 /* First fill the buffer with the current register set contents,
5194 in case there are any items in the kernel's regset that are
5195 not in gdbserver's regcache. */
5197 nt_type
= regset
->nt_type
;
5201 iov
.iov_len
= regset
->size
;
5202 data
= (void *) &iov
;
5208 res
= ptrace (regset
->get_request
, pid
,
5209 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5211 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
5216 /* Then overlay our cached registers on that. */
5217 regset
->fill_function (regcache
, buf
);
5219 /* Only now do we write the register set. */
5221 res
= ptrace (regset
->set_request
, pid
,
5222 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5224 res
= ptrace (regset
->set_request
, pid
, data
, nt_type
);
5231 || (errno
== EINVAL
&& regset
->type
== OPTIONAL_REGS
))
5233 /* If we get EIO on a regset, or an EINVAL and the regset is
5234 optional, do not try it again for this process mode. */
5235 disable_regset (regsets_info
, regset
);
5237 else if (errno
== ESRCH
)
5239 /* At this point, ESRCH should mean the process is
5240 already gone, in which case we simply ignore attempts
5241 to change its registers. See also the related
5242 comment in resume_one_lwp. */
5248 perror ("Warning: ptrace(regsets_store_inferior_registers)");
5251 else if (regset
->type
== GENERAL_REGS
)
5252 saw_general_regs
= 1;
5255 if (saw_general_regs
)
5261 #else /* !HAVE_LINUX_REGSETS */
5263 #define use_linux_regsets 0
5264 #define regsets_fetch_inferior_registers(regsets_info, regcache) 1
5265 #define regsets_store_inferior_registers(regsets_info, regcache) 1
5269 /* Return 1 if register REGNO is supported by one of the regset ptrace
5270 calls or 0 if it has to be transferred individually. */
5273 linux_register_in_regsets (const struct regs_info
*regs_info
, int regno
)
5275 unsigned char mask
= 1 << (regno
% 8);
5276 size_t index
= regno
/ 8;
5278 return (use_linux_regsets
5279 && (regs_info
->regset_bitmap
== NULL
5280 || (regs_info
->regset_bitmap
[index
] & mask
) != 0));
5283 #ifdef HAVE_LINUX_USRREGS
5286 register_addr (const struct usrregs_info
*usrregs
, int regnum
)
5290 if (regnum
< 0 || regnum
>= usrregs
->num_regs
)
5291 error ("Invalid register number %d.", regnum
);
5293 addr
= usrregs
->regmap
[regnum
];
5300 linux_process_target::fetch_register (const usrregs_info
*usrregs
,
5301 regcache
*regcache
, int regno
)
5308 if (regno
>= usrregs
->num_regs
)
5310 if (low_cannot_fetch_register (regno
))
5313 regaddr
= register_addr (usrregs
, regno
);
5317 size
= ((register_size (regcache
->tdesc
, regno
)
5318 + sizeof (PTRACE_XFER_TYPE
) - 1)
5319 & -sizeof (PTRACE_XFER_TYPE
));
5320 buf
= (char *) alloca (size
);
5322 pid
= lwpid_of (current_thread
);
5323 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
5326 *(PTRACE_XFER_TYPE
*) (buf
+ i
) =
5327 ptrace (PTRACE_PEEKUSER
, pid
,
5328 /* Coerce to a uintptr_t first to avoid potential gcc warning
5329 of coercing an 8 byte integer to a 4 byte pointer. */
5330 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
, (PTRACE_TYPE_ARG4
) 0);
5331 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
5334 /* Mark register REGNO unavailable. */
5335 supply_register (regcache
, regno
, NULL
);
5340 low_supply_ptrace_register (regcache
, regno
, buf
);
5344 linux_process_target::store_register (const usrregs_info
*usrregs
,
5345 regcache
*regcache
, int regno
)
5352 if (regno
>= usrregs
->num_regs
)
5354 if (low_cannot_store_register (regno
))
5357 regaddr
= register_addr (usrregs
, regno
);
5361 size
= ((register_size (regcache
->tdesc
, regno
)
5362 + sizeof (PTRACE_XFER_TYPE
) - 1)
5363 & -sizeof (PTRACE_XFER_TYPE
));
5364 buf
= (char *) alloca (size
);
5365 memset (buf
, 0, size
);
5367 low_collect_ptrace_register (regcache
, regno
, buf
);
5369 pid
= lwpid_of (current_thread
);
5370 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
5373 ptrace (PTRACE_POKEUSER
, pid
,
5374 /* Coerce to a uintptr_t first to avoid potential gcc warning
5375 about coercing an 8 byte integer to a 4 byte pointer. */
5376 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
,
5377 (PTRACE_TYPE_ARG4
) *(PTRACE_XFER_TYPE
*) (buf
+ i
));
5380 /* At this point, ESRCH should mean the process is
5381 already gone, in which case we simply ignore attempts
5382 to change its registers. See also the related
5383 comment in resume_one_lwp. */
5388 if (!low_cannot_store_register (regno
))
5389 error ("writing register %d: %s", regno
, safe_strerror (errno
));
5391 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
5394 #endif /* HAVE_LINUX_USRREGS */
5397 linux_process_target::low_collect_ptrace_register (regcache
*regcache
,
5398 int regno
, char *buf
)
5400 collect_register (regcache
, regno
, buf
);
5404 linux_process_target::low_supply_ptrace_register (regcache
*regcache
,
5405 int regno
, const char *buf
)
5407 supply_register (regcache
, regno
, buf
);
5411 linux_process_target::usr_fetch_inferior_registers (const regs_info
*regs_info
,
5415 #ifdef HAVE_LINUX_USRREGS
5416 struct usrregs_info
*usr
= regs_info
->usrregs
;
5420 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
5421 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
5422 fetch_register (usr
, regcache
, regno
);
5425 fetch_register (usr
, regcache
, regno
);
5430 linux_process_target::usr_store_inferior_registers (const regs_info
*regs_info
,
5434 #ifdef HAVE_LINUX_USRREGS
5435 struct usrregs_info
*usr
= regs_info
->usrregs
;
5439 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
5440 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
5441 store_register (usr
, regcache
, regno
);
5444 store_register (usr
, regcache
, regno
);
5449 linux_process_target::fetch_registers (regcache
*regcache
, int regno
)
5453 const regs_info
*regs_info
= get_regs_info ();
5457 if (regs_info
->usrregs
!= NULL
)
5458 for (regno
= 0; regno
< regs_info
->usrregs
->num_regs
; regno
++)
5459 low_fetch_register (regcache
, regno
);
5461 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
, regcache
);
5462 if (regs_info
->usrregs
!= NULL
)
5463 usr_fetch_inferior_registers (regs_info
, regcache
, -1, all
);
5467 if (low_fetch_register (regcache
, regno
))
5470 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
5472 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
,
5474 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
5475 usr_fetch_inferior_registers (regs_info
, regcache
, regno
, 1);
5480 linux_process_target::store_registers (regcache
*regcache
, int regno
)
5484 const regs_info
*regs_info
= get_regs_info ();
5488 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
5490 if (regs_info
->usrregs
!= NULL
)
5491 usr_store_inferior_registers (regs_info
, regcache
, regno
, all
);
5495 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
5497 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
5499 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
5500 usr_store_inferior_registers (regs_info
, regcache
, regno
, 1);
5505 linux_process_target::low_fetch_register (regcache
*regcache
, int regno
)
5510 /* A wrapper for the read_memory target op. */
5513 linux_read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
, int len
)
5515 return the_target
->read_memory (memaddr
, myaddr
, len
);
5518 /* Copy LEN bytes from inferior's memory starting at MEMADDR
5519 to debugger memory starting at MYADDR. */
5522 linux_process_target::read_memory (CORE_ADDR memaddr
,
5523 unsigned char *myaddr
, int len
)
5525 int pid
= lwpid_of (current_thread
);
5526 PTRACE_XFER_TYPE
*buffer
;
5534 /* Try using /proc. Don't bother for one word. */
5535 if (len
>= 3 * sizeof (long))
5539 /* We could keep this file open and cache it - possibly one per
5540 thread. That requires some juggling, but is even faster. */
5541 sprintf (filename
, "/proc/%d/mem", pid
);
5542 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
5546 /* If pread64 is available, use it. It's faster if the kernel
5547 supports it (only one syscall), and it's 64-bit safe even on
5548 32-bit platforms (for instance, SPARC debugging a SPARC64
5551 bytes
= pread64 (fd
, myaddr
, len
, memaddr
);
5554 if (lseek (fd
, memaddr
, SEEK_SET
) != -1)
5555 bytes
= read (fd
, myaddr
, len
);
5562 /* Some data was read, we'll try to get the rest with ptrace. */
5572 /* Round starting address down to longword boundary. */
5573 addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
5574 /* Round ending address up; get number of longwords that makes. */
5575 count
= ((((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
5576 / sizeof (PTRACE_XFER_TYPE
));
5577 /* Allocate buffer of that many longwords. */
5578 buffer
= XALLOCAVEC (PTRACE_XFER_TYPE
, count
);
5580 /* Read all the longwords */
5582 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
5584 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5585 about coercing an 8 byte integer to a 4 byte pointer. */
5586 buffer
[i
] = ptrace (PTRACE_PEEKTEXT
, pid
,
5587 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5588 (PTRACE_TYPE_ARG4
) 0);
5594 /* Copy appropriate bytes out of the buffer. */
5597 i
*= sizeof (PTRACE_XFER_TYPE
);
5598 i
-= memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1);
5600 (char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
5607 /* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
5608 memory at MEMADDR. On failure (cannot write to the inferior)
5609 returns the value of errno. Always succeeds if LEN is zero. */
5612 linux_process_target::write_memory (CORE_ADDR memaddr
,
5613 const unsigned char *myaddr
, int len
)
5616 /* Round starting address down to longword boundary. */
5617 CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
5618 /* Round ending address up; get number of longwords that makes. */
5620 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
5621 / sizeof (PTRACE_XFER_TYPE
);
5623 /* Allocate buffer of that many longwords. */
5624 PTRACE_XFER_TYPE
*buffer
= XALLOCAVEC (PTRACE_XFER_TYPE
, count
);
5626 int pid
= lwpid_of (current_thread
);
5630 /* Zero length write always succeeds. */
5636 /* Dump up to four bytes. */
5637 char str
[4 * 2 + 1];
5639 int dump
= len
< 4 ? len
: 4;
5641 for (i
= 0; i
< dump
; i
++)
5643 sprintf (p
, "%02x", myaddr
[i
]);
5648 debug_printf ("Writing %s to 0x%08lx in process %d\n",
5649 str
, (long) memaddr
, pid
);
5652 /* Fill start and end extra bytes of buffer with existing memory data. */
5655 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5656 about coercing an 8 byte integer to a 4 byte pointer. */
5657 buffer
[0] = ptrace (PTRACE_PEEKTEXT
, pid
,
5658 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5659 (PTRACE_TYPE_ARG4
) 0);
5667 = ptrace (PTRACE_PEEKTEXT
, pid
,
5668 /* Coerce to a uintptr_t first to avoid potential gcc warning
5669 about coercing an 8 byte integer to a 4 byte pointer. */
5670 (PTRACE_TYPE_ARG3
) (uintptr_t) (addr
+ (count
- 1)
5671 * sizeof (PTRACE_XFER_TYPE
)),
5672 (PTRACE_TYPE_ARG4
) 0);
5677 /* Copy data to be written over corresponding part of buffer. */
5679 memcpy ((char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
5682 /* Write the entire buffer. */
5684 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
5687 ptrace (PTRACE_POKETEXT
, pid
,
5688 /* Coerce to a uintptr_t first to avoid potential gcc warning
5689 about coercing an 8 byte integer to a 4 byte pointer. */
5690 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5691 (PTRACE_TYPE_ARG4
) buffer
[i
]);
5700 linux_process_target::look_up_symbols ()
5702 #ifdef USE_THREAD_DB
5703 struct process_info
*proc
= current_process ();
5705 if (proc
->priv
->thread_db
!= NULL
)
5713 linux_process_target::request_interrupt ()
5715 /* Send a SIGINT to the process group. This acts just like the user
5716 typed a ^C on the controlling terminal. */
5717 ::kill (-signal_pid
, SIGINT
);
5721 linux_process_target::supports_read_auxv ()
5726 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
5727 to debugger memory starting at MYADDR. */
5730 linux_process_target::read_auxv (CORE_ADDR offset
, unsigned char *myaddr
,
5733 char filename
[PATH_MAX
];
5735 int pid
= lwpid_of (current_thread
);
5737 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
5739 fd
= open (filename
, O_RDONLY
);
5743 if (offset
!= (CORE_ADDR
) 0
5744 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
5747 n
= read (fd
, myaddr
, len
);
5755 linux_process_target::insert_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
5756 int size
, raw_breakpoint
*bp
)
5758 if (type
== raw_bkpt_type_sw
)
5759 return insert_memory_breakpoint (bp
);
5761 return low_insert_point (type
, addr
, size
, bp
);
5765 linux_process_target::low_insert_point (raw_bkpt_type type
, CORE_ADDR addr
,
5766 int size
, raw_breakpoint
*bp
)
5768 /* Unsupported (see target.h). */
5773 linux_process_target::remove_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
5774 int size
, raw_breakpoint
*bp
)
5776 if (type
== raw_bkpt_type_sw
)
5777 return remove_memory_breakpoint (bp
);
5779 return low_remove_point (type
, addr
, size
, bp
);
5783 linux_process_target::low_remove_point (raw_bkpt_type type
, CORE_ADDR addr
,
5784 int size
, raw_breakpoint
*bp
)
5786 /* Unsupported (see target.h). */
5790 /* Implement the stopped_by_sw_breakpoint target_ops
5794 linux_process_target::stopped_by_sw_breakpoint ()
5796 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5798 return (lwp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
);
5801 /* Implement the supports_stopped_by_sw_breakpoint target_ops
5805 linux_process_target::supports_stopped_by_sw_breakpoint ()
5807 return USE_SIGTRAP_SIGINFO
;
5810 /* Implement the stopped_by_hw_breakpoint target_ops
5814 linux_process_target::stopped_by_hw_breakpoint ()
5816 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5818 return (lwp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
);
5821 /* Implement the supports_stopped_by_hw_breakpoint target_ops
5825 linux_process_target::supports_stopped_by_hw_breakpoint ()
5827 return USE_SIGTRAP_SIGINFO
;
5830 /* Implement the supports_hardware_single_step target_ops method. */
5833 linux_process_target::supports_hardware_single_step ()
5839 linux_process_target::stopped_by_watchpoint ()
5841 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5843 return lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
;
5847 linux_process_target::stopped_data_address ()
5849 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5851 return lwp
->stopped_data_address
;
5854 /* This is only used for targets that define PT_TEXT_ADDR,
5855 PT_DATA_ADDR and PT_TEXT_END_ADDR. If those are not defined, supposedly
5856 the target has different ways of acquiring this information, like
5860 linux_process_target::supports_read_offsets ()
5862 #ifdef SUPPORTS_READ_OFFSETS
5869 /* Under uClinux, programs are loaded at non-zero offsets, which we need
5870 to tell gdb about. */
5873 linux_process_target::read_offsets (CORE_ADDR
*text_p
, CORE_ADDR
*data_p
)
5875 #ifdef SUPPORTS_READ_OFFSETS
5876 unsigned long text
, text_end
, data
;
5877 int pid
= lwpid_of (current_thread
);
5881 text
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_ADDR
,
5882 (PTRACE_TYPE_ARG4
) 0);
5883 text_end
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_END_ADDR
,
5884 (PTRACE_TYPE_ARG4
) 0);
5885 data
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_DATA_ADDR
,
5886 (PTRACE_TYPE_ARG4
) 0);
5890 /* Both text and data offsets produced at compile-time (and so
5891 used by gdb) are relative to the beginning of the program,
5892 with the data segment immediately following the text segment.
5893 However, the actual runtime layout in memory may put the data
5894 somewhere else, so when we send gdb a data base-address, we
5895 use the real data base address and subtract the compile-time
5896 data base-address from it (which is just the length of the
5897 text segment). BSS immediately follows data in both
5900 *data_p
= data
- (text_end
- text
);
5906 gdb_assert_not_reached ("target op read_offsets not supported");
5911 linux_process_target::supports_get_tls_address ()
5913 #ifdef USE_THREAD_DB
5921 linux_process_target::get_tls_address (thread_info
*thread
,
5923 CORE_ADDR load_module
,
5926 #ifdef USE_THREAD_DB
5927 return thread_db_get_tls_address (thread
, offset
, load_module
, address
);
5934 linux_process_target::supports_qxfer_osdata ()
5940 linux_process_target::qxfer_osdata (const char *annex
,
5941 unsigned char *readbuf
,
5942 unsigned const char *writebuf
,
5943 CORE_ADDR offset
, int len
)
5945 return linux_common_xfer_osdata (annex
, readbuf
, offset
, len
);
5949 linux_process_target::siginfo_fixup (siginfo_t
*siginfo
,
5950 gdb_byte
*inf_siginfo
, int direction
)
5952 bool done
= low_siginfo_fixup (siginfo
, inf_siginfo
, direction
);
5954 /* If there was no callback, or the callback didn't do anything,
5955 then just do a straight memcpy. */
5959 memcpy (siginfo
, inf_siginfo
, sizeof (siginfo_t
));
5961 memcpy (inf_siginfo
, siginfo
, sizeof (siginfo_t
));
5966 linux_process_target::low_siginfo_fixup (siginfo_t
*native
, gdb_byte
*inf
,
5973 linux_process_target::supports_qxfer_siginfo ()
5979 linux_process_target::qxfer_siginfo (const char *annex
,
5980 unsigned char *readbuf
,
5981 unsigned const char *writebuf
,
5982 CORE_ADDR offset
, int len
)
5986 gdb_byte inf_siginfo
[sizeof (siginfo_t
)];
5988 if (current_thread
== NULL
)
5991 pid
= lwpid_of (current_thread
);
5994 debug_printf ("%s siginfo for lwp %d.\n",
5995 readbuf
!= NULL
? "Reading" : "Writing",
5998 if (offset
>= sizeof (siginfo
))
6001 if (ptrace (PTRACE_GETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
6004 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
6005 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
6006 inferior with a 64-bit GDBSERVER should look the same as debugging it
6007 with a 32-bit GDBSERVER, we need to convert it. */
6008 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
6010 if (offset
+ len
> sizeof (siginfo
))
6011 len
= sizeof (siginfo
) - offset
;
6013 if (readbuf
!= NULL
)
6014 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
6017 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
6019 /* Convert back to ptrace layout before flushing it out. */
6020 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
6022 if (ptrace (PTRACE_SETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
6029 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
6030 so we notice when children change state; as the handler for the
6031 sigsuspend in my_waitpid. */
6034 sigchld_handler (int signo
)
6036 int old_errno
= errno
;
6042 /* Use the async signal safe debug function. */
6043 if (debug_write ("sigchld_handler\n",
6044 sizeof ("sigchld_handler\n") - 1) < 0)
6045 break; /* just ignore */
6049 if (target_is_async_p ())
6050 async_file_mark (); /* trigger a linux_wait */
6056 linux_process_target::supports_non_stop ()
6062 linux_process_target::async (bool enable
)
6064 bool previous
= target_is_async_p ();
6067 debug_printf ("linux_async (%d), previous=%d\n",
6070 if (previous
!= enable
)
6073 sigemptyset (&mask
);
6074 sigaddset (&mask
, SIGCHLD
);
6076 gdb_sigmask (SIG_BLOCK
, &mask
, NULL
);
6080 if (pipe (linux_event_pipe
) == -1)
6082 linux_event_pipe
[0] = -1;
6083 linux_event_pipe
[1] = -1;
6084 gdb_sigmask (SIG_UNBLOCK
, &mask
, NULL
);
6086 warning ("creating event pipe failed.");
6090 fcntl (linux_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
6091 fcntl (linux_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
6093 /* Register the event loop handler. */
6094 add_file_handler (linux_event_pipe
[0],
6095 handle_target_event
, NULL
);
6097 /* Always trigger a linux_wait. */
6102 delete_file_handler (linux_event_pipe
[0]);
6104 close (linux_event_pipe
[0]);
6105 close (linux_event_pipe
[1]);
6106 linux_event_pipe
[0] = -1;
6107 linux_event_pipe
[1] = -1;
6110 gdb_sigmask (SIG_UNBLOCK
, &mask
, NULL
);
6117 linux_process_target::start_non_stop (bool nonstop
)
6119 /* Register or unregister from event-loop accordingly. */
6120 target_async (nonstop
);
6122 if (target_is_async_p () != (nonstop
!= false))
6129 linux_process_target::supports_multi_process ()
6134 /* Check if fork events are supported. */
6137 linux_process_target::supports_fork_events ()
6139 return linux_supports_tracefork ();
6142 /* Check if vfork events are supported. */
6145 linux_process_target::supports_vfork_events ()
6147 return linux_supports_tracefork ();
6150 /* Check if exec events are supported. */
6153 linux_process_target::supports_exec_events ()
6155 return linux_supports_traceexec ();
6158 /* Target hook for 'handle_new_gdb_connection'. Causes a reset of the
6159 ptrace flags for all inferiors. This is in case the new GDB connection
6160 doesn't support the same set of events that the previous one did. */
6163 linux_process_target::handle_new_gdb_connection ()
6165 /* Request that all the lwps reset their ptrace options. */
6166 for_each_thread ([] (thread_info
*thread
)
6168 struct lwp_info
*lwp
= get_thread_lwp (thread
);
6172 /* Stop the lwp so we can modify its ptrace options. */
6173 lwp
->must_set_ptrace_flags
= 1;
6174 linux_stop_lwp (lwp
);
6178 /* Already stopped; go ahead and set the ptrace options. */
6179 struct process_info
*proc
= find_process_pid (pid_of (thread
));
6180 int options
= linux_low_ptrace_options (proc
->attached
);
6182 linux_enable_event_reporting (lwpid_of (thread
), options
);
6183 lwp
->must_set_ptrace_flags
= 0;
6189 linux_process_target::handle_monitor_command (char *mon
)
6191 #ifdef USE_THREAD_DB
6192 return thread_db_handle_monitor_command (mon
);
6199 linux_process_target::core_of_thread (ptid_t ptid
)
6201 return linux_common_core_of_thread (ptid
);
6205 linux_process_target::supports_disable_randomization ()
6207 #ifdef HAVE_PERSONALITY
6215 linux_process_target::supports_agent ()
6221 linux_process_target::supports_range_stepping ()
6223 if (supports_software_single_step ())
6226 return low_supports_range_stepping ();
6230 linux_process_target::low_supports_range_stepping ()
6236 linux_process_target::supports_pid_to_exec_file ()
6242 linux_process_target::pid_to_exec_file (int pid
)
6244 return linux_proc_pid_to_exec_file (pid
);
6248 linux_process_target::supports_multifs ()
6254 linux_process_target::multifs_open (int pid
, const char *filename
,
6255 int flags
, mode_t mode
)
6257 return linux_mntns_open_cloexec (pid
, filename
, flags
, mode
);
6261 linux_process_target::multifs_unlink (int pid
, const char *filename
)
6263 return linux_mntns_unlink (pid
, filename
);
6267 linux_process_target::multifs_readlink (int pid
, const char *filename
,
6268 char *buf
, size_t bufsiz
)
6270 return linux_mntns_readlink (pid
, filename
, buf
, bufsiz
);
6273 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
6274 struct target_loadseg
6276 /* Core address to which the segment is mapped. */
6278 /* VMA recorded in the program header. */
6280 /* Size of this segment in memory. */
6284 # if defined PT_GETDSBT
6285 struct target_loadmap
6287 /* Protocol version number, must be zero. */
6289 /* Pointer to the DSBT table, its size, and the DSBT index. */
6290 unsigned *dsbt_table
;
6291 unsigned dsbt_size
, dsbt_index
;
6292 /* Number of segments in this map. */
6294 /* The actual memory map. */
6295 struct target_loadseg segs
[/*nsegs*/];
6297 # define LINUX_LOADMAP PT_GETDSBT
6298 # define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
6299 # define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
6301 struct target_loadmap
6303 /* Protocol version number, must be zero. */
6305 /* Number of segments in this map. */
6307 /* The actual memory map. */
6308 struct target_loadseg segs
[/*nsegs*/];
6310 # define LINUX_LOADMAP PTRACE_GETFDPIC
6311 # define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
6312 # define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
6316 linux_process_target::supports_read_loadmap ()
6322 linux_process_target::read_loadmap (const char *annex
, CORE_ADDR offset
,
6323 unsigned char *myaddr
, unsigned int len
)
6325 int pid
= lwpid_of (current_thread
);
6327 struct target_loadmap
*data
= NULL
;
6328 unsigned int actual_length
, copy_length
;
6330 if (strcmp (annex
, "exec") == 0)
6331 addr
= (int) LINUX_LOADMAP_EXEC
;
6332 else if (strcmp (annex
, "interp") == 0)
6333 addr
= (int) LINUX_LOADMAP_INTERP
;
6337 if (ptrace (LINUX_LOADMAP
, pid
, addr
, &data
) != 0)
6343 actual_length
= sizeof (struct target_loadmap
)
6344 + sizeof (struct target_loadseg
) * data
->nsegs
;
6346 if (offset
< 0 || offset
> actual_length
)
6349 copy_length
= actual_length
- offset
< len
? actual_length
- offset
: len
;
6350 memcpy (myaddr
, (char *) data
+ offset
, copy_length
);
6353 #endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
6356 linux_process_target::supports_catch_syscall ()
6358 return (low_supports_catch_syscall ()
6359 && linux_supports_tracesysgood ());
6363 linux_process_target::low_supports_catch_syscall ()
6369 linux_process_target::read_pc (regcache
*regcache
)
6371 if (!low_supports_breakpoints ())
6374 return low_get_pc (regcache
);
6378 linux_process_target::write_pc (regcache
*regcache
, CORE_ADDR pc
)
6380 gdb_assert (low_supports_breakpoints ());
6382 low_set_pc (regcache
, pc
);
6386 linux_process_target::supports_thread_stopped ()
6392 linux_process_target::thread_stopped (thread_info
*thread
)
6394 return get_thread_lwp (thread
)->stopped
;
6397 /* This exposes stop-all-threads functionality to other modules. */
6400 linux_process_target::pause_all (bool freeze
)
6402 stop_all_lwps (freeze
, NULL
);
6405 /* This exposes unstop-all-threads functionality to other gdbserver
6409 linux_process_target::unpause_all (bool unfreeze
)
6411 unstop_all_lwps (unfreeze
, NULL
);
6415 linux_process_target::prepare_to_access_memory ()
6417 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6420 target_pause_all (true);
6425 linux_process_target::done_accessing_memory ()
6427 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6430 target_unpause_all (true);
6433 /* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
6436 get_phdr_phnum_from_proc_auxv (const int pid
, const int is_elf64
,
6437 CORE_ADDR
*phdr_memaddr
, int *num_phdr
)
6439 char filename
[PATH_MAX
];
6441 const int auxv_size
= is_elf64
6442 ? sizeof (Elf64_auxv_t
) : sizeof (Elf32_auxv_t
);
6443 char buf
[sizeof (Elf64_auxv_t
)]; /* The larger of the two. */
6445 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
6447 fd
= open (filename
, O_RDONLY
);
6453 while (read (fd
, buf
, auxv_size
) == auxv_size
6454 && (*phdr_memaddr
== 0 || *num_phdr
== 0))
6458 Elf64_auxv_t
*const aux
= (Elf64_auxv_t
*) buf
;
6460 switch (aux
->a_type
)
6463 *phdr_memaddr
= aux
->a_un
.a_val
;
6466 *num_phdr
= aux
->a_un
.a_val
;
6472 Elf32_auxv_t
*const aux
= (Elf32_auxv_t
*) buf
;
6474 switch (aux
->a_type
)
6477 *phdr_memaddr
= aux
->a_un
.a_val
;
6480 *num_phdr
= aux
->a_un
.a_val
;
6488 if (*phdr_memaddr
== 0 || *num_phdr
== 0)
6490 warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
6491 "phdr_memaddr = %ld, phdr_num = %d",
6492 (long) *phdr_memaddr
, *num_phdr
);
6499 /* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
6502 get_dynamic (const int pid
, const int is_elf64
)
6504 CORE_ADDR phdr_memaddr
, relocation
;
6506 unsigned char *phdr_buf
;
6507 const int phdr_size
= is_elf64
? sizeof (Elf64_Phdr
) : sizeof (Elf32_Phdr
);
6509 if (get_phdr_phnum_from_proc_auxv (pid
, is_elf64
, &phdr_memaddr
, &num_phdr
))
6512 gdb_assert (num_phdr
< 100); /* Basic sanity check. */
6513 phdr_buf
= (unsigned char *) alloca (num_phdr
* phdr_size
);
6515 if (linux_read_memory (phdr_memaddr
, phdr_buf
, num_phdr
* phdr_size
))
6518 /* Compute relocation: it is expected to be 0 for "regular" executables,
6519 non-zero for PIE ones. */
6521 for (i
= 0; relocation
== -1 && i
< num_phdr
; i
++)
6524 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6526 if (p
->p_type
== PT_PHDR
)
6527 relocation
= phdr_memaddr
- p
->p_vaddr
;
6531 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6533 if (p
->p_type
== PT_PHDR
)
6534 relocation
= phdr_memaddr
- p
->p_vaddr
;
6537 if (relocation
== -1)
6539 /* PT_PHDR is optional, but necessary for PIE in general. Fortunately
6540 any real world executables, including PIE executables, have always
6541 PT_PHDR present. PT_PHDR is not present in some shared libraries or
6542 in fpc (Free Pascal 2.4) binaries but neither of those have a need for
6543 or present DT_DEBUG anyway (fpc binaries are statically linked).
6545 Therefore if there exists DT_DEBUG there is always also PT_PHDR.
6547 GDB could find RELOCATION also from AT_ENTRY - e_entry. */
6552 for (i
= 0; i
< num_phdr
; i
++)
6556 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6558 if (p
->p_type
== PT_DYNAMIC
)
6559 return p
->p_vaddr
+ relocation
;
6563 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6565 if (p
->p_type
== PT_DYNAMIC
)
6566 return p
->p_vaddr
+ relocation
;
6573 /* Return &_r_debug in the inferior, or -1 if not present. Return value
6574 can be 0 if the inferior does not yet have the library list initialized.
6575 We look for DT_MIPS_RLD_MAP first. MIPS executables use this instead of
6576 DT_DEBUG, although they sometimes contain an unused DT_DEBUG entry too. */
6579 get_r_debug (const int pid
, const int is_elf64
)
6581 CORE_ADDR dynamic_memaddr
;
6582 const int dyn_size
= is_elf64
? sizeof (Elf64_Dyn
) : sizeof (Elf32_Dyn
);
6583 unsigned char buf
[sizeof (Elf64_Dyn
)]; /* The larger of the two. */
6586 dynamic_memaddr
= get_dynamic (pid
, is_elf64
);
6587 if (dynamic_memaddr
== 0)
6590 while (linux_read_memory (dynamic_memaddr
, buf
, dyn_size
) == 0)
6594 Elf64_Dyn
*const dyn
= (Elf64_Dyn
*) buf
;
6595 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
6599 unsigned char buf
[sizeof (Elf64_Xword
)];
6603 #ifdef DT_MIPS_RLD_MAP
6604 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
6606 if (linux_read_memory (dyn
->d_un
.d_val
,
6607 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6612 #endif /* DT_MIPS_RLD_MAP */
6613 #ifdef DT_MIPS_RLD_MAP_REL
6614 if (dyn
->d_tag
== DT_MIPS_RLD_MAP_REL
)
6616 if (linux_read_memory (dyn
->d_un
.d_val
+ dynamic_memaddr
,
6617 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6622 #endif /* DT_MIPS_RLD_MAP_REL */
6624 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
6625 map
= dyn
->d_un
.d_val
;
6627 if (dyn
->d_tag
== DT_NULL
)
6632 Elf32_Dyn
*const dyn
= (Elf32_Dyn
*) buf
;
6633 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
6637 unsigned char buf
[sizeof (Elf32_Word
)];
6641 #ifdef DT_MIPS_RLD_MAP
6642 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
6644 if (linux_read_memory (dyn
->d_un
.d_val
,
6645 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6650 #endif /* DT_MIPS_RLD_MAP */
6651 #ifdef DT_MIPS_RLD_MAP_REL
6652 if (dyn
->d_tag
== DT_MIPS_RLD_MAP_REL
)
6654 if (linux_read_memory (dyn
->d_un
.d_val
+ dynamic_memaddr
,
6655 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6660 #endif /* DT_MIPS_RLD_MAP_REL */
6662 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
6663 map
= dyn
->d_un
.d_val
;
6665 if (dyn
->d_tag
== DT_NULL
)
6669 dynamic_memaddr
+= dyn_size
;
6675 /* Read one pointer from MEMADDR in the inferior. */
6678 read_one_ptr (CORE_ADDR memaddr
, CORE_ADDR
*ptr
, int ptr_size
)
6682 /* Go through a union so this works on either big or little endian
6683 hosts, when the inferior's pointer size is smaller than the size
6684 of CORE_ADDR. It is assumed the inferior's endianness is the
6685 same of the superior's. */
6688 CORE_ADDR core_addr
;
6693 ret
= linux_read_memory (memaddr
, &addr
.uc
, ptr_size
);
6696 if (ptr_size
== sizeof (CORE_ADDR
))
6697 *ptr
= addr
.core_addr
;
6698 else if (ptr_size
== sizeof (unsigned int))
6701 gdb_assert_not_reached ("unhandled pointer size");
6707 linux_process_target::supports_qxfer_libraries_svr4 ()
6712 struct link_map_offsets
6714 /* Offset and size of r_debug.r_version. */
6715 int r_version_offset
;
6717 /* Offset and size of r_debug.r_map. */
6720 /* Offset to l_addr field in struct link_map. */
6723 /* Offset to l_name field in struct link_map. */
6726 /* Offset to l_ld field in struct link_map. */
6729 /* Offset to l_next field in struct link_map. */
6732 /* Offset to l_prev field in struct link_map. */
6736 /* Construct qXfer:libraries-svr4:read reply. */
6739 linux_process_target::qxfer_libraries_svr4 (const char *annex
,
6740 unsigned char *readbuf
,
6741 unsigned const char *writebuf
,
6742 CORE_ADDR offset
, int len
)
6744 struct process_info_private
*const priv
= current_process ()->priv
;
6745 char filename
[PATH_MAX
];
6748 static const struct link_map_offsets lmo_32bit_offsets
=
6750 0, /* r_version offset. */
6751 4, /* r_debug.r_map offset. */
6752 0, /* l_addr offset in link_map. */
6753 4, /* l_name offset in link_map. */
6754 8, /* l_ld offset in link_map. */
6755 12, /* l_next offset in link_map. */
6756 16 /* l_prev offset in link_map. */
6759 static const struct link_map_offsets lmo_64bit_offsets
=
6761 0, /* r_version offset. */
6762 8, /* r_debug.r_map offset. */
6763 0, /* l_addr offset in link_map. */
6764 8, /* l_name offset in link_map. */
6765 16, /* l_ld offset in link_map. */
6766 24, /* l_next offset in link_map. */
6767 32 /* l_prev offset in link_map. */
6769 const struct link_map_offsets
*lmo
;
6770 unsigned int machine
;
6772 CORE_ADDR lm_addr
= 0, lm_prev
= 0;
6773 CORE_ADDR l_name
, l_addr
, l_ld
, l_next
, l_prev
;
6774 int header_done
= 0;
6776 if (writebuf
!= NULL
)
6778 if (readbuf
== NULL
)
6781 pid
= lwpid_of (current_thread
);
6782 xsnprintf (filename
, sizeof filename
, "/proc/%d/exe", pid
);
6783 is_elf64
= elf_64_file_p (filename
, &machine
);
6784 lmo
= is_elf64
? &lmo_64bit_offsets
: &lmo_32bit_offsets
;
6785 ptr_size
= is_elf64
? 8 : 4;
6787 while (annex
[0] != '\0')
6793 sep
= strchr (annex
, '=');
6797 name_len
= sep
- annex
;
6798 if (name_len
== 5 && startswith (annex
, "start"))
6800 else if (name_len
== 4 && startswith (annex
, "prev"))
6804 annex
= strchr (sep
, ';');
6811 annex
= decode_address_to_semicolon (addrp
, sep
+ 1);
6818 if (priv
->r_debug
== 0)
6819 priv
->r_debug
= get_r_debug (pid
, is_elf64
);
6821 /* We failed to find DT_DEBUG. Such situation will not change
6822 for this inferior - do not retry it. Report it to GDB as
6823 E01, see for the reasons at the GDB solib-svr4.c side. */
6824 if (priv
->r_debug
== (CORE_ADDR
) -1)
6827 if (priv
->r_debug
!= 0)
6829 if (linux_read_memory (priv
->r_debug
+ lmo
->r_version_offset
,
6830 (unsigned char *) &r_version
,
6831 sizeof (r_version
)) != 0
6834 warning ("unexpected r_debug version %d", r_version
);
6836 else if (read_one_ptr (priv
->r_debug
+ lmo
->r_map_offset
,
6837 &lm_addr
, ptr_size
) != 0)
6839 warning ("unable to read r_map from 0x%lx",
6840 (long) priv
->r_debug
+ lmo
->r_map_offset
);
6845 std::string document
= "<library-list-svr4 version=\"1.0\"";
6848 && read_one_ptr (lm_addr
+ lmo
->l_name_offset
,
6849 &l_name
, ptr_size
) == 0
6850 && read_one_ptr (lm_addr
+ lmo
->l_addr_offset
,
6851 &l_addr
, ptr_size
) == 0
6852 && read_one_ptr (lm_addr
+ lmo
->l_ld_offset
,
6853 &l_ld
, ptr_size
) == 0
6854 && read_one_ptr (lm_addr
+ lmo
->l_prev_offset
,
6855 &l_prev
, ptr_size
) == 0
6856 && read_one_ptr (lm_addr
+ lmo
->l_next_offset
,
6857 &l_next
, ptr_size
) == 0)
6859 unsigned char libname
[PATH_MAX
];
6861 if (lm_prev
!= l_prev
)
6863 warning ("Corrupted shared library list: 0x%lx != 0x%lx",
6864 (long) lm_prev
, (long) l_prev
);
6868 /* Ignore the first entry even if it has valid name as the first entry
6869 corresponds to the main executable. The first entry should not be
6870 skipped if the dynamic loader was loaded late by a static executable
6871 (see solib-svr4.c parameter ignore_first). But in such case the main
6872 executable does not have PT_DYNAMIC present and this function already
6873 exited above due to failed get_r_debug. */
6875 string_appendf (document
, " main-lm=\"0x%lx\"", (unsigned long) lm_addr
);
6878 /* Not checking for error because reading may stop before
6879 we've got PATH_MAX worth of characters. */
6881 linux_read_memory (l_name
, libname
, sizeof (libname
) - 1);
6882 libname
[sizeof (libname
) - 1] = '\0';
6883 if (libname
[0] != '\0')
6887 /* Terminate `<library-list-svr4'. */
6892 string_appendf (document
, "<library name=\"");
6893 xml_escape_text_append (&document
, (char *) libname
);
6894 string_appendf (document
, "\" lm=\"0x%lx\" "
6895 "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
6896 (unsigned long) lm_addr
, (unsigned long) l_addr
,
6897 (unsigned long) l_ld
);
6907 /* Empty list; terminate `<library-list-svr4'. */
6911 document
+= "</library-list-svr4>";
6913 int document_len
= document
.length ();
6914 if (offset
< document_len
)
6915 document_len
-= offset
;
6918 if (len
> document_len
)
6921 memcpy (readbuf
, document
.data () + offset
, len
);
6926 #ifdef HAVE_LINUX_BTRACE
6928 btrace_target_info
*
6929 linux_process_target::enable_btrace (ptid_t ptid
,
6930 const btrace_config
*conf
)
6932 return linux_enable_btrace (ptid
, conf
);
6935 /* See to_disable_btrace target method. */
6938 linux_process_target::disable_btrace (btrace_target_info
*tinfo
)
6940 enum btrace_error err
;
6942 err
= linux_disable_btrace (tinfo
);
6943 return (err
== BTRACE_ERR_NONE
? 0 : -1);
6946 /* Encode an Intel Processor Trace configuration. */
6949 linux_low_encode_pt_config (struct buffer
*buffer
,
6950 const struct btrace_data_pt_config
*config
)
6952 buffer_grow_str (buffer
, "<pt-config>\n");
6954 switch (config
->cpu
.vendor
)
6957 buffer_xml_printf (buffer
, "<cpu vendor=\"GenuineIntel\" family=\"%u\" "
6958 "model=\"%u\" stepping=\"%u\"/>\n",
6959 config
->cpu
.family
, config
->cpu
.model
,
6960 config
->cpu
.stepping
);
6967 buffer_grow_str (buffer
, "</pt-config>\n");
6970 /* Encode a raw buffer. */
6973 linux_low_encode_raw (struct buffer
*buffer
, const gdb_byte
*data
,
6979 /* We use hex encoding - see gdbsupport/rsp-low.h. */
6980 buffer_grow_str (buffer
, "<raw>\n");
6986 elem
[0] = tohex ((*data
>> 4) & 0xf);
6987 elem
[1] = tohex (*data
++ & 0xf);
6989 buffer_grow (buffer
, elem
, 2);
6992 buffer_grow_str (buffer
, "</raw>\n");
6995 /* See to_read_btrace target method. */
6998 linux_process_target::read_btrace (btrace_target_info
*tinfo
,
7000 enum btrace_read_type type
)
7002 struct btrace_data btrace
;
7003 enum btrace_error err
;
7005 err
= linux_read_btrace (&btrace
, tinfo
, type
);
7006 if (err
!= BTRACE_ERR_NONE
)
7008 if (err
== BTRACE_ERR_OVERFLOW
)
7009 buffer_grow_str0 (buffer
, "E.Overflow.");
7011 buffer_grow_str0 (buffer
, "E.Generic Error.");
7016 switch (btrace
.format
)
7018 case BTRACE_FORMAT_NONE
:
7019 buffer_grow_str0 (buffer
, "E.No Trace.");
7022 case BTRACE_FORMAT_BTS
:
7023 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
7024 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
7026 for (const btrace_block
&block
: *btrace
.variant
.bts
.blocks
)
7027 buffer_xml_printf (buffer
, "<block begin=\"0x%s\" end=\"0x%s\"/>\n",
7028 paddress (block
.begin
), paddress (block
.end
));
7030 buffer_grow_str0 (buffer
, "</btrace>\n");
7033 case BTRACE_FORMAT_PT
:
7034 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
7035 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
7036 buffer_grow_str (buffer
, "<pt>\n");
7038 linux_low_encode_pt_config (buffer
, &btrace
.variant
.pt
.config
);
7040 linux_low_encode_raw (buffer
, btrace
.variant
.pt
.data
,
7041 btrace
.variant
.pt
.size
);
7043 buffer_grow_str (buffer
, "</pt>\n");
7044 buffer_grow_str0 (buffer
, "</btrace>\n");
7048 buffer_grow_str0 (buffer
, "E.Unsupported Trace Format.");
7055 /* See to_btrace_conf target method. */
7058 linux_process_target::read_btrace_conf (const btrace_target_info
*tinfo
,
7061 const struct btrace_config
*conf
;
7063 buffer_grow_str (buffer
, "<!DOCTYPE btrace-conf SYSTEM \"btrace-conf.dtd\">\n");
7064 buffer_grow_str (buffer
, "<btrace-conf version=\"1.0\">\n");
7066 conf
= linux_btrace_conf (tinfo
);
7069 switch (conf
->format
)
7071 case BTRACE_FORMAT_NONE
:
7074 case BTRACE_FORMAT_BTS
:
7075 buffer_xml_printf (buffer
, "<bts");
7076 buffer_xml_printf (buffer
, " size=\"0x%x\"", conf
->bts
.size
);
7077 buffer_xml_printf (buffer
, " />\n");
7080 case BTRACE_FORMAT_PT
:
7081 buffer_xml_printf (buffer
, "<pt");
7082 buffer_xml_printf (buffer
, " size=\"0x%x\"", conf
->pt
.size
);
7083 buffer_xml_printf (buffer
, "/>\n");
7088 buffer_grow_str0 (buffer
, "</btrace-conf>\n");
7091 #endif /* HAVE_LINUX_BTRACE */
7093 /* See nat/linux-nat.h. */
7096 current_lwp_ptid (void)
7098 return ptid_of (current_thread
);
7102 linux_process_target::thread_name (ptid_t thread
)
7104 return linux_proc_tid_get_name (thread
);
7109 linux_process_target::thread_handle (ptid_t ptid
, gdb_byte
**handle
,
7112 return thread_db_thread_handle (ptid
, handle
, handle_len
);
7116 /* Default implementation of linux_target_ops method "set_pc" for
7117 32-bit pc register which is literally named "pc". */
7120 linux_set_pc_32bit (struct regcache
*regcache
, CORE_ADDR pc
)
7122 uint32_t newpc
= pc
;
7124 supply_register_by_name (regcache
, "pc", &newpc
);
7127 /* Default implementation of linux_target_ops method "get_pc" for
7128 32-bit pc register which is literally named "pc". */
7131 linux_get_pc_32bit (struct regcache
*regcache
)
7135 collect_register_by_name (regcache
, "pc", &pc
);
7137 debug_printf ("stop pc is 0x%" PRIx32
"\n", pc
);
7141 /* Default implementation of linux_target_ops method "set_pc" for
7142 64-bit pc register which is literally named "pc". */
7145 linux_set_pc_64bit (struct regcache
*regcache
, CORE_ADDR pc
)
7147 uint64_t newpc
= pc
;
7149 supply_register_by_name (regcache
, "pc", &newpc
);
7152 /* Default implementation of linux_target_ops method "get_pc" for
7153 64-bit pc register which is literally named "pc". */
7156 linux_get_pc_64bit (struct regcache
*regcache
)
7160 collect_register_by_name (regcache
, "pc", &pc
);
7162 debug_printf ("stop pc is 0x%" PRIx64
"\n", pc
);
7166 /* See linux-low.h. */
7169 linux_get_auxv (int wordsize
, CORE_ADDR match
, CORE_ADDR
*valp
)
7171 gdb_byte
*data
= (gdb_byte
*) alloca (2 * wordsize
);
7174 gdb_assert (wordsize
== 4 || wordsize
== 8);
7176 while (the_target
->read_auxv (offset
, data
, 2 * wordsize
) == 2 * wordsize
)
7180 uint32_t *data_p
= (uint32_t *) data
;
7181 if (data_p
[0] == match
)
7189 uint64_t *data_p
= (uint64_t *) data
;
7190 if (data_p
[0] == match
)
7197 offset
+= 2 * wordsize
;
7203 /* See linux-low.h. */
7206 linux_get_hwcap (int wordsize
)
7208 CORE_ADDR hwcap
= 0;
7209 linux_get_auxv (wordsize
, AT_HWCAP
, &hwcap
);
7213 /* See linux-low.h. */
7216 linux_get_hwcap2 (int wordsize
)
7218 CORE_ADDR hwcap2
= 0;
7219 linux_get_auxv (wordsize
, AT_HWCAP2
, &hwcap2
);
7223 #ifdef HAVE_LINUX_REGSETS
7225 initialize_regsets_info (struct regsets_info
*info
)
7227 for (info
->num_regsets
= 0;
7228 info
->regsets
[info
->num_regsets
].size
>= 0;
7229 info
->num_regsets
++)
7235 initialize_low (void)
7237 struct sigaction sigchld_action
;
7239 memset (&sigchld_action
, 0, sizeof (sigchld_action
));
7240 set_target_ops (the_linux_target
);
7242 linux_ptrace_init_warnings ();
7243 linux_proc_init_warnings ();
7245 sigchld_action
.sa_handler
= sigchld_handler
;
7246 sigemptyset (&sigchld_action
.sa_mask
);
7247 sigchld_action
.sa_flags
= SA_RESTART
;
7248 sigaction (SIGCHLD
, &sigchld_action
, NULL
);
7250 initialize_low_arch ();
7252 linux_check_ptrace_features ();