1 /* Low level interface to ptrace, for the remote server for GDB.
2 Copyright (C) 1995-2021 Free Software Foundation, Inc.
4 This file is part of GDB.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>. */
20 #include "linux-low.h"
21 #include "nat/linux-osdata.h"
22 #include "gdbsupport/agent.h"
24 #include "gdbsupport/rsp-low.h"
25 #include "gdbsupport/signals-state-save-restore.h"
26 #include "nat/linux-nat.h"
27 #include "nat/linux-waitpid.h"
28 #include "gdbsupport/gdb_wait.h"
29 #include "nat/gdb_ptrace.h"
30 #include "nat/linux-ptrace.h"
31 #include "nat/linux-procfs.h"
32 #include "nat/linux-personality.h"
34 #include <sys/ioctl.h>
37 #include <sys/syscall.h>
41 #include <sys/types.h>
46 #include "gdbsupport/filestuff.h"
47 #include "tracepoint.h"
49 #include "gdbsupport/common-inferior.h"
50 #include "nat/fork-inferior.h"
51 #include "gdbsupport/environ.h"
52 #include "gdbsupport/gdb-sigmask.h"
53 #include "gdbsupport/scoped_restore.h"
55 /* Don't include <linux/elf.h> here. If it got included by gdb_proc_service.h
56 then ELFMAG0 will have been defined. If it didn't get included by
57 gdb_proc_service.h then including it will likely introduce a duplicate
58 definition of elf_fpregset_t. */
61 #include "nat/linux-namespaces.h"
71 /* Some targets did not define these ptrace constants from the start,
72 so gdbserver defines them locally here. In the future, these may
73 be removed after they are added to asm/ptrace.h. */
74 #if !(defined(PT_TEXT_ADDR) \
75 || defined(PT_DATA_ADDR) \
76 || defined(PT_TEXT_END_ADDR))
77 #if defined(__mcoldfire__)
78 /* These are still undefined in 3.10 kernels. */
79 #define PT_TEXT_ADDR 49*4
80 #define PT_DATA_ADDR 50*4
81 #define PT_TEXT_END_ADDR 51*4
82 /* These are still undefined in 3.10 kernels. */
83 #elif defined(__TMS320C6X__)
84 #define PT_TEXT_ADDR (0x10000*4)
85 #define PT_DATA_ADDR (0x10004*4)
86 #define PT_TEXT_END_ADDR (0x10008*4)
90 #if (defined(__UCLIBC__) \
91 && defined(HAS_NOMMU) \
92 && defined(PT_TEXT_ADDR) \
93 && defined(PT_DATA_ADDR) \
94 && defined(PT_TEXT_END_ADDR))
95 #define SUPPORTS_READ_OFFSETS
98 #ifdef HAVE_LINUX_BTRACE
99 # include "nat/linux-btrace.h"
100 # include "gdbsupport/btrace-common.h"
103 #ifndef HAVE_ELF32_AUXV_T
104 /* Copied from glibc's elf.h. */
107 uint32_t a_type
; /* Entry type */
110 uint32_t a_val
; /* Integer value */
111 /* We use to have pointer elements added here. We cannot do that,
112 though, since it does not work when using 32-bit definitions
113 on 64-bit platforms and vice versa. */
118 #ifndef HAVE_ELF64_AUXV_T
119 /* Copied from glibc's elf.h. */
122 uint64_t a_type
; /* Entry type */
125 uint64_t a_val
; /* Integer value */
126 /* We use to have pointer elements added here. We cannot do that,
127 though, since it does not work when using 32-bit definitions
128 on 64-bit platforms and vice versa. */
133 /* Does the current host support PTRACE_GETREGSET? */
134 int have_ptrace_getregset
= -1;
138 /* See nat/linux-nat.h. */
141 ptid_of_lwp (struct lwp_info
*lwp
)
143 return ptid_of (get_lwp_thread (lwp
));
146 /* See nat/linux-nat.h. */
149 lwp_set_arch_private_info (struct lwp_info
*lwp
,
150 struct arch_lwp_info
*info
)
152 lwp
->arch_private
= info
;
155 /* See nat/linux-nat.h. */
157 struct arch_lwp_info
*
158 lwp_arch_private_info (struct lwp_info
*lwp
)
160 return lwp
->arch_private
;
163 /* See nat/linux-nat.h. */
166 lwp_is_stopped (struct lwp_info
*lwp
)
171 /* See nat/linux-nat.h. */
173 enum target_stop_reason
174 lwp_stop_reason (struct lwp_info
*lwp
)
176 return lwp
->stop_reason
;
179 /* See nat/linux-nat.h. */
182 lwp_is_stepping (struct lwp_info
*lwp
)
184 return lwp
->stepping
;
187 /* A list of all unknown processes which receive stop signals. Some
188 other process will presumably claim each of these as forked
189 children momentarily. */
191 struct simple_pid_list
193 /* The process ID. */
196 /* The status as reported by waitpid. */
200 struct simple_pid_list
*next
;
202 static struct simple_pid_list
*stopped_pids
;
204 /* Trivial list manipulation functions to keep track of a list of new
205 stopped processes. */
208 add_to_pid_list (struct simple_pid_list
**listp
, int pid
, int status
)
210 struct simple_pid_list
*new_pid
= XNEW (struct simple_pid_list
);
213 new_pid
->status
= status
;
214 new_pid
->next
= *listp
;
219 pull_pid_from_list (struct simple_pid_list
**listp
, int pid
, int *statusp
)
221 struct simple_pid_list
**p
;
223 for (p
= listp
; *p
!= NULL
; p
= &(*p
)->next
)
224 if ((*p
)->pid
== pid
)
226 struct simple_pid_list
*next
= (*p
)->next
;
228 *statusp
= (*p
)->status
;
236 enum stopping_threads_kind
238 /* Not stopping threads presently. */
239 NOT_STOPPING_THREADS
,
241 /* Stopping threads. */
244 /* Stopping and suspending threads. */
245 STOPPING_AND_SUSPENDING_THREADS
248 /* This is set while stop_all_lwps is in effect. */
249 static stopping_threads_kind stopping_threads
= NOT_STOPPING_THREADS
;
251 /* FIXME make into a target method? */
252 int using_threads
= 1;
254 /* True if we're presently stabilizing threads (moving them out of
256 static int stabilizing_threads
;
258 static void unsuspend_all_lwps (struct lwp_info
*except
);
259 static void mark_lwp_dead (struct lwp_info
*lwp
, int wstat
);
260 static int lwp_is_marked_dead (struct lwp_info
*lwp
);
261 static int kill_lwp (unsigned long lwpid
, int signo
);
262 static void enqueue_pending_signal (struct lwp_info
*lwp
, int signal
, siginfo_t
*info
);
263 static int linux_low_ptrace_options (int attached
);
264 static int check_ptrace_stopped_lwp_gone (struct lwp_info
*lp
);
266 /* When the event-loop is doing a step-over, this points at the thread
268 static ptid_t step_over_bkpt
;
271 linux_process_target::low_supports_breakpoints ()
277 linux_process_target::low_get_pc (regcache
*regcache
)
283 linux_process_target::low_set_pc (regcache
*regcache
, CORE_ADDR newpc
)
285 gdb_assert_not_reached ("linux target op low_set_pc is not implemented");
288 std::vector
<CORE_ADDR
>
289 linux_process_target::low_get_next_pcs (regcache
*regcache
)
291 gdb_assert_not_reached ("linux target op low_get_next_pcs is not "
296 linux_process_target::low_decr_pc_after_break ()
301 /* True if LWP is stopped in its stepping range. */
304 lwp_in_step_range (struct lwp_info
*lwp
)
306 CORE_ADDR pc
= lwp
->stop_pc
;
308 return (pc
>= lwp
->step_range_start
&& pc
< lwp
->step_range_end
);
311 /* The read/write ends of the pipe registered as waitable file in the
313 static int linux_event_pipe
[2] = { -1, -1 };
315 /* True if we're currently in async mode. */
316 #define target_is_async_p() (linux_event_pipe[0] != -1)
318 static void send_sigstop (struct lwp_info
*lwp
);
320 /* Return non-zero if HEADER is a 64-bit ELF file. */
323 elf_64_header_p (const Elf64_Ehdr
*header
, unsigned int *machine
)
325 if (header
->e_ident
[EI_MAG0
] == ELFMAG0
326 && header
->e_ident
[EI_MAG1
] == ELFMAG1
327 && header
->e_ident
[EI_MAG2
] == ELFMAG2
328 && header
->e_ident
[EI_MAG3
] == ELFMAG3
)
330 *machine
= header
->e_machine
;
331 return header
->e_ident
[EI_CLASS
] == ELFCLASS64
;
338 /* Return non-zero if FILE is a 64-bit ELF file,
339 zero if the file is not a 64-bit ELF file,
340 and -1 if the file is not accessible or doesn't exist. */
343 elf_64_file_p (const char *file
, unsigned int *machine
)
348 fd
= open (file
, O_RDONLY
);
352 if (read (fd
, &header
, sizeof (header
)) != sizeof (header
))
359 return elf_64_header_p (&header
, machine
);
362 /* Accepts an integer PID; Returns true if the executable PID is
363 running is a 64-bit ELF file.. */
366 linux_pid_exe_is_elf_64_file (int pid
, unsigned int *machine
)
370 sprintf (file
, "/proc/%d/exe", pid
);
371 return elf_64_file_p (file
, machine
);
375 linux_process_target::delete_lwp (lwp_info
*lwp
)
377 struct thread_info
*thr
= get_lwp_thread (lwp
);
380 debug_printf ("deleting %ld\n", lwpid_of (thr
));
384 low_delete_thread (lwp
->arch_private
);
390 linux_process_target::low_delete_thread (arch_lwp_info
*info
)
392 /* Default implementation should be overridden if architecture-specific
393 info is being used. */
394 gdb_assert (info
== nullptr);
398 linux_process_target::add_linux_process (int pid
, int attached
)
400 struct process_info
*proc
;
402 proc
= add_process (pid
, attached
);
403 proc
->priv
= XCNEW (struct process_info_private
);
405 proc
->priv
->arch_private
= low_new_process ();
411 linux_process_target::low_new_process ()
417 linux_process_target::low_delete_process (arch_process_info
*info
)
419 /* Default implementation must be overridden if architecture-specific
421 gdb_assert (info
== nullptr);
425 linux_process_target::low_new_fork (process_info
*parent
, process_info
*child
)
431 linux_process_target::arch_setup_thread (thread_info
*thread
)
433 struct thread_info
*saved_thread
;
435 saved_thread
= current_thread
;
436 current_thread
= thread
;
440 current_thread
= saved_thread
;
444 linux_process_target::handle_extended_wait (lwp_info
**orig_event_lwp
,
447 client_state
&cs
= get_client_state ();
448 struct lwp_info
*event_lwp
= *orig_event_lwp
;
449 int event
= linux_ptrace_get_extended_event (wstat
);
450 struct thread_info
*event_thr
= get_lwp_thread (event_lwp
);
451 struct lwp_info
*new_lwp
;
453 gdb_assert (event_lwp
->waitstatus
.kind () == TARGET_WAITKIND_IGNORE
);
455 /* All extended events we currently use are mid-syscall. Only
456 PTRACE_EVENT_STOP is delivered more like a signal-stop, but
457 you have to be using PTRACE_SEIZE to get that. */
458 event_lwp
->syscall_state
= TARGET_WAITKIND_SYSCALL_ENTRY
;
460 if ((event
== PTRACE_EVENT_FORK
) || (event
== PTRACE_EVENT_VFORK
)
461 || (event
== PTRACE_EVENT_CLONE
))
464 unsigned long new_pid
;
467 /* Get the pid of the new lwp. */
468 ptrace (PTRACE_GETEVENTMSG
, lwpid_of (event_thr
), (PTRACE_TYPE_ARG3
) 0,
471 /* If we haven't already seen the new PID stop, wait for it now. */
472 if (!pull_pid_from_list (&stopped_pids
, new_pid
, &status
))
474 /* The new child has a pending SIGSTOP. We can't affect it until it
475 hits the SIGSTOP, but we're already attached. */
477 ret
= my_waitpid (new_pid
, &status
, __WALL
);
480 perror_with_name ("waiting for new child");
481 else if (ret
!= new_pid
)
482 warning ("wait returned unexpected PID %d", ret
);
483 else if (!WIFSTOPPED (status
))
484 warning ("wait returned unexpected status 0x%x", status
);
487 if (event
== PTRACE_EVENT_FORK
|| event
== PTRACE_EVENT_VFORK
)
489 struct process_info
*parent_proc
;
490 struct process_info
*child_proc
;
491 struct lwp_info
*child_lwp
;
492 struct thread_info
*child_thr
;
494 ptid
= ptid_t (new_pid
, new_pid
);
498 debug_printf ("HEW: Got fork event from LWP %ld, "
500 ptid_of (event_thr
).lwp (),
504 /* Add the new process to the tables and clone the breakpoint
505 lists of the parent. We need to do this even if the new process
506 will be detached, since we will need the process object and the
507 breakpoints to remove any breakpoints from memory when we
508 detach, and the client side will access registers. */
509 child_proc
= add_linux_process (new_pid
, 0);
510 gdb_assert (child_proc
!= NULL
);
511 child_lwp
= add_lwp (ptid
);
512 gdb_assert (child_lwp
!= NULL
);
513 child_lwp
->stopped
= 1;
514 child_lwp
->must_set_ptrace_flags
= 1;
515 child_lwp
->status_pending_p
= 0;
516 child_thr
= get_lwp_thread (child_lwp
);
517 child_thr
->last_resume_kind
= resume_stop
;
518 child_thr
->last_status
.set_stopped (GDB_SIGNAL_0
);
520 /* If we're suspending all threads, leave this one suspended
521 too. If the fork/clone parent is stepping over a breakpoint,
522 all other threads have been suspended already. Leave the
523 child suspended too. */
524 if (stopping_threads
== STOPPING_AND_SUSPENDING_THREADS
525 || event_lwp
->bp_reinsert
!= 0)
528 debug_printf ("HEW: leaving child suspended\n");
529 child_lwp
->suspended
= 1;
532 parent_proc
= get_thread_process (event_thr
);
533 child_proc
->attached
= parent_proc
->attached
;
535 if (event_lwp
->bp_reinsert
!= 0
536 && supports_software_single_step ()
537 && event
== PTRACE_EVENT_VFORK
)
539 /* If we leave single-step breakpoints there, child will
540 hit it, so uninsert single-step breakpoints from parent
541 (and child). Once vfork child is done, reinsert
542 them back to parent. */
543 uninsert_single_step_breakpoints (event_thr
);
546 clone_all_breakpoints (child_thr
, event_thr
);
548 target_desc_up tdesc
= allocate_target_description ();
549 copy_target_description (tdesc
.get (), parent_proc
->tdesc
);
550 child_proc
->tdesc
= tdesc
.release ();
552 /* Clone arch-specific process data. */
553 low_new_fork (parent_proc
, child_proc
);
555 /* Save fork info in the parent thread. */
556 if (event
== PTRACE_EVENT_FORK
)
557 event_lwp
->waitstatus
.set_forked (ptid
);
558 else if (event
== PTRACE_EVENT_VFORK
)
559 event_lwp
->waitstatus
.set_vforked (ptid
);
561 /* The status_pending field contains bits denoting the
562 extended event, so when the pending event is handled,
563 the handler will look at lwp->waitstatus. */
564 event_lwp
->status_pending_p
= 1;
565 event_lwp
->status_pending
= wstat
;
567 /* Link the threads until the parent event is passed on to
569 event_lwp
->fork_relative
= child_lwp
;
570 child_lwp
->fork_relative
= event_lwp
;
572 /* If the parent thread is doing step-over with single-step
573 breakpoints, the list of single-step breakpoints are cloned
574 from the parent's. Remove them from the child process.
575 In case of vfork, we'll reinsert them back once vforked
577 if (event_lwp
->bp_reinsert
!= 0
578 && supports_software_single_step ())
580 /* The child process is forked and stopped, so it is safe
581 to access its memory without stopping all other threads
582 from other processes. */
583 delete_single_step_breakpoints (child_thr
);
585 gdb_assert (has_single_step_breakpoints (event_thr
));
586 gdb_assert (!has_single_step_breakpoints (child_thr
));
589 /* Report the event. */
594 debug_printf ("HEW: Got clone event "
595 "from LWP %ld, new child is LWP %ld\n",
596 lwpid_of (event_thr
), new_pid
);
598 ptid
= ptid_t (pid_of (event_thr
), new_pid
);
599 new_lwp
= add_lwp (ptid
);
601 /* Either we're going to immediately resume the new thread
602 or leave it stopped. resume_one_lwp is a nop if it
603 thinks the thread is currently running, so set this first
604 before calling resume_one_lwp. */
605 new_lwp
->stopped
= 1;
607 /* If we're suspending all threads, leave this one suspended
608 too. If the fork/clone parent is stepping over a breakpoint,
609 all other threads have been suspended already. Leave the
610 child suspended too. */
611 if (stopping_threads
== STOPPING_AND_SUSPENDING_THREADS
612 || event_lwp
->bp_reinsert
!= 0)
613 new_lwp
->suspended
= 1;
615 /* Normally we will get the pending SIGSTOP. But in some cases
616 we might get another signal delivered to the group first.
617 If we do get another signal, be sure not to lose it. */
618 if (WSTOPSIG (status
) != SIGSTOP
)
620 new_lwp
->stop_expected
= 1;
621 new_lwp
->status_pending_p
= 1;
622 new_lwp
->status_pending
= status
;
624 else if (cs
.report_thread_events
)
626 new_lwp
->waitstatus
.set_thread_created ();
627 new_lwp
->status_pending_p
= 1;
628 new_lwp
->status_pending
= status
;
632 thread_db_notice_clone (event_thr
, ptid
);
635 /* Don't report the event. */
638 else if (event
== PTRACE_EVENT_VFORK_DONE
)
640 event_lwp
->waitstatus
.set_vfork_done ();
642 if (event_lwp
->bp_reinsert
!= 0 && supports_software_single_step ())
644 reinsert_single_step_breakpoints (event_thr
);
646 gdb_assert (has_single_step_breakpoints (event_thr
));
649 /* Report the event. */
652 else if (event
== PTRACE_EVENT_EXEC
&& cs
.report_exec_events
)
654 struct process_info
*proc
;
655 std::vector
<int> syscalls_to_catch
;
661 debug_printf ("HEW: Got exec event from LWP %ld\n",
662 lwpid_of (event_thr
));
665 /* Get the event ptid. */
666 event_ptid
= ptid_of (event_thr
);
667 event_pid
= event_ptid
.pid ();
669 /* Save the syscall list from the execing process. */
670 proc
= get_thread_process (event_thr
);
671 syscalls_to_catch
= std::move (proc
->syscalls_to_catch
);
673 /* Delete the execing process and all its threads. */
675 current_thread
= NULL
;
677 /* Create a new process/lwp/thread. */
678 proc
= add_linux_process (event_pid
, 0);
679 event_lwp
= add_lwp (event_ptid
);
680 event_thr
= get_lwp_thread (event_lwp
);
681 gdb_assert (current_thread
== event_thr
);
682 arch_setup_thread (event_thr
);
684 /* Set the event status. */
685 event_lwp
->waitstatus
.set_execd
687 (linux_proc_pid_to_exec_file (lwpid_of (event_thr
))));
689 /* Mark the exec status as pending. */
690 event_lwp
->stopped
= 1;
691 event_lwp
->status_pending_p
= 1;
692 event_lwp
->status_pending
= wstat
;
693 event_thr
->last_resume_kind
= resume_continue
;
694 event_thr
->last_status
.set_ignore ();
696 /* Update syscall state in the new lwp, effectively mid-syscall too. */
697 event_lwp
->syscall_state
= TARGET_WAITKIND_SYSCALL_ENTRY
;
699 /* Restore the list to catch. Don't rely on the client, which is free
700 to avoid sending a new list when the architecture doesn't change.
701 Also, for ANY_SYSCALL, the architecture doesn't really matter. */
702 proc
->syscalls_to_catch
= std::move (syscalls_to_catch
);
704 /* Report the event. */
705 *orig_event_lwp
= event_lwp
;
709 internal_error (__FILE__
, __LINE__
, _("unknown ptrace event %d"), event
);
713 linux_process_target::get_pc (lwp_info
*lwp
)
715 struct thread_info
*saved_thread
;
716 struct regcache
*regcache
;
719 if (!low_supports_breakpoints ())
722 saved_thread
= current_thread
;
723 current_thread
= get_lwp_thread (lwp
);
725 regcache
= get_thread_regcache (current_thread
, 1);
726 pc
= low_get_pc (regcache
);
729 debug_printf ("pc is 0x%lx\n", (long) pc
);
731 current_thread
= saved_thread
;
736 linux_process_target::get_syscall_trapinfo (lwp_info
*lwp
, int *sysno
)
738 struct thread_info
*saved_thread
;
739 struct regcache
*regcache
;
741 saved_thread
= current_thread
;
742 current_thread
= get_lwp_thread (lwp
);
744 regcache
= get_thread_regcache (current_thread
, 1);
745 low_get_syscall_trapinfo (regcache
, sysno
);
748 debug_printf ("get_syscall_trapinfo sysno %d\n", *sysno
);
750 current_thread
= saved_thread
;
754 linux_process_target::low_get_syscall_trapinfo (regcache
*regcache
, int *sysno
)
756 /* By default, report an unknown system call number. */
757 *sysno
= UNKNOWN_SYSCALL
;
761 linux_process_target::save_stop_reason (lwp_info
*lwp
)
764 CORE_ADDR sw_breakpoint_pc
;
765 struct thread_info
*saved_thread
;
766 #if USE_SIGTRAP_SIGINFO
770 if (!low_supports_breakpoints ())
774 sw_breakpoint_pc
= pc
- low_decr_pc_after_break ();
776 /* breakpoint_at reads from the current thread. */
777 saved_thread
= current_thread
;
778 current_thread
= get_lwp_thread (lwp
);
780 #if USE_SIGTRAP_SIGINFO
781 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
782 (PTRACE_TYPE_ARG3
) 0, &siginfo
) == 0)
784 if (siginfo
.si_signo
== SIGTRAP
)
786 if (GDB_ARCH_IS_TRAP_BRKPT (siginfo
.si_code
)
787 && GDB_ARCH_IS_TRAP_HWBKPT (siginfo
.si_code
))
789 /* The si_code is ambiguous on this arch -- check debug
791 if (!check_stopped_by_watchpoint (lwp
))
792 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
794 else if (GDB_ARCH_IS_TRAP_BRKPT (siginfo
.si_code
))
796 /* If we determine the LWP stopped for a SW breakpoint,
797 trust it. Particularly don't check watchpoint
798 registers, because at least on s390, we'd find
799 stopped-by-watchpoint as long as there's a watchpoint
801 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
803 else if (GDB_ARCH_IS_TRAP_HWBKPT (siginfo
.si_code
))
805 /* This can indicate either a hardware breakpoint or
806 hardware watchpoint. Check debug registers. */
807 if (!check_stopped_by_watchpoint (lwp
))
808 lwp
->stop_reason
= TARGET_STOPPED_BY_HW_BREAKPOINT
;
810 else if (siginfo
.si_code
== TRAP_TRACE
)
812 /* We may have single stepped an instruction that
813 triggered a watchpoint. In that case, on some
814 architectures (such as x86), instead of TRAP_HWBKPT,
815 si_code indicates TRAP_TRACE, and we need to check
816 the debug registers separately. */
817 if (!check_stopped_by_watchpoint (lwp
))
818 lwp
->stop_reason
= TARGET_STOPPED_BY_SINGLE_STEP
;
823 /* We may have just stepped a breakpoint instruction. E.g., in
824 non-stop mode, GDB first tells the thread A to step a range, and
825 then the user inserts a breakpoint inside the range. In that
826 case we need to report the breakpoint PC. */
827 if ((!lwp
->stepping
|| lwp
->stop_pc
== sw_breakpoint_pc
)
828 && low_breakpoint_at (sw_breakpoint_pc
))
829 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
831 if (hardware_breakpoint_inserted_here (pc
))
832 lwp
->stop_reason
= TARGET_STOPPED_BY_HW_BREAKPOINT
;
834 if (lwp
->stop_reason
== TARGET_STOPPED_BY_NO_REASON
)
835 check_stopped_by_watchpoint (lwp
);
838 if (lwp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
)
842 struct thread_info
*thr
= get_lwp_thread (lwp
);
844 debug_printf ("CSBB: %s stopped by software breakpoint\n",
845 target_pid_to_str (ptid_of (thr
)).c_str ());
848 /* Back up the PC if necessary. */
849 if (pc
!= sw_breakpoint_pc
)
851 struct regcache
*regcache
852 = get_thread_regcache (current_thread
, 1);
853 low_set_pc (regcache
, sw_breakpoint_pc
);
856 /* Update this so we record the correct stop PC below. */
857 pc
= sw_breakpoint_pc
;
859 else if (lwp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
)
863 struct thread_info
*thr
= get_lwp_thread (lwp
);
865 debug_printf ("CSBB: %s stopped by hardware breakpoint\n",
866 target_pid_to_str (ptid_of (thr
)).c_str ());
869 else if (lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
)
873 struct thread_info
*thr
= get_lwp_thread (lwp
);
875 debug_printf ("CSBB: %s stopped by hardware watchpoint\n",
876 target_pid_to_str (ptid_of (thr
)).c_str ());
879 else if (lwp
->stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
)
883 struct thread_info
*thr
= get_lwp_thread (lwp
);
885 debug_printf ("CSBB: %s stopped by trace\n",
886 target_pid_to_str (ptid_of (thr
)).c_str ());
891 current_thread
= saved_thread
;
896 linux_process_target::add_lwp (ptid_t ptid
)
898 lwp_info
*lwp
= new lwp_info
;
900 lwp
->thread
= add_thread (ptid
, lwp
);
902 low_new_thread (lwp
);
908 linux_process_target::low_new_thread (lwp_info
*info
)
913 /* Callback to be used when calling fork_inferior, responsible for
914 actually initiating the tracing of the inferior. */
919 if (ptrace (PTRACE_TRACEME
, 0, (PTRACE_TYPE_ARG3
) 0,
920 (PTRACE_TYPE_ARG4
) 0) < 0)
921 trace_start_error_with_name ("ptrace");
923 if (setpgid (0, 0) < 0)
924 trace_start_error_with_name ("setpgid");
926 /* If GDBserver is connected to gdb via stdio, redirect the inferior's
927 stdout to stderr so that inferior i/o doesn't corrupt the connection.
928 Also, redirect stdin to /dev/null. */
929 if (remote_connection_is_stdio ())
932 trace_start_error_with_name ("close");
933 if (open ("/dev/null", O_RDONLY
) < 0)
934 trace_start_error_with_name ("open");
936 trace_start_error_with_name ("dup2");
937 if (write (2, "stdin/stdout redirected\n",
938 sizeof ("stdin/stdout redirected\n") - 1) < 0)
940 /* Errors ignored. */;
945 /* Start an inferior process and returns its pid.
946 PROGRAM is the name of the program to be started, and PROGRAM_ARGS
947 are its arguments. */
950 linux_process_target::create_inferior (const char *program
,
951 const std::vector
<char *> &program_args
)
953 client_state
&cs
= get_client_state ();
954 struct lwp_info
*new_lwp
;
959 maybe_disable_address_space_randomization restore_personality
960 (cs
.disable_randomization
);
961 std::string str_program_args
= construct_inferior_arguments (program_args
);
963 pid
= fork_inferior (program
,
964 str_program_args
.c_str (),
965 get_environ ()->envp (), linux_ptrace_fun
,
966 NULL
, NULL
, NULL
, NULL
);
969 add_linux_process (pid
, 0);
971 ptid
= ptid_t (pid
, pid
);
972 new_lwp
= add_lwp (ptid
);
973 new_lwp
->must_set_ptrace_flags
= 1;
975 post_fork_inferior (pid
, program
);
980 /* Implement the post_create_inferior target_ops method. */
983 linux_process_target::post_create_inferior ()
985 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
989 if (lwp
->must_set_ptrace_flags
)
991 struct process_info
*proc
= current_process ();
992 int options
= linux_low_ptrace_options (proc
->attached
);
994 linux_enable_event_reporting (lwpid_of (current_thread
), options
);
995 lwp
->must_set_ptrace_flags
= 0;
1000 linux_process_target::attach_lwp (ptid_t ptid
)
1002 struct lwp_info
*new_lwp
;
1003 int lwpid
= ptid
.lwp ();
1005 if (ptrace (PTRACE_ATTACH
, lwpid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0)
1009 new_lwp
= add_lwp (ptid
);
1011 /* We need to wait for SIGSTOP before being able to make the next
1012 ptrace call on this LWP. */
1013 new_lwp
->must_set_ptrace_flags
= 1;
1015 if (linux_proc_pid_is_stopped (lwpid
))
1018 debug_printf ("Attached to a stopped process\n");
1020 /* The process is definitely stopped. It is in a job control
1021 stop, unless the kernel predates the TASK_STOPPED /
1022 TASK_TRACED distinction, in which case it might be in a
1023 ptrace stop. Make sure it is in a ptrace stop; from there we
1024 can kill it, signal it, et cetera.
1026 First make sure there is a pending SIGSTOP. Since we are
1027 already attached, the process can not transition from stopped
1028 to running without a PTRACE_CONT; so we know this signal will
1029 go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
1030 probably already in the queue (unless this kernel is old
1031 enough to use TASK_STOPPED for ptrace stops); but since
1032 SIGSTOP is not an RT signal, it can only be queued once. */
1033 kill_lwp (lwpid
, SIGSTOP
);
1035 /* Finally, resume the stopped process. This will deliver the
1036 SIGSTOP (or a higher priority signal, just like normal
1037 PTRACE_ATTACH), which we'll catch later on. */
1038 ptrace (PTRACE_CONT
, lwpid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
1041 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
1042 brings it to a halt.
1044 There are several cases to consider here:
1046 1) gdbserver has already attached to the process and is being notified
1047 of a new thread that is being created.
1048 In this case we should ignore that SIGSTOP and resume the
1049 process. This is handled below by setting stop_expected = 1,
1050 and the fact that add_thread sets last_resume_kind ==
1053 2) This is the first thread (the process thread), and we're attaching
1054 to it via attach_inferior.
1055 In this case we want the process thread to stop.
1056 This is handled by having linux_attach set last_resume_kind ==
1057 resume_stop after we return.
1059 If the pid we are attaching to is also the tgid, we attach to and
1060 stop all the existing threads. Otherwise, we attach to pid and
1061 ignore any other threads in the same group as this pid.
1063 3) GDB is connecting to gdbserver and is requesting an enumeration of all
1065 In this case we want the thread to stop.
1066 FIXME: This case is currently not properly handled.
1067 We should wait for the SIGSTOP but don't. Things work apparently
1068 because enough time passes between when we ptrace (ATTACH) and when
1069 gdb makes the next ptrace call on the thread.
1071 On the other hand, if we are currently trying to stop all threads, we
1072 should treat the new thread as if we had sent it a SIGSTOP. This works
1073 because we are guaranteed that the add_lwp call above added us to the
1074 end of the list, and so the new thread has not yet reached
1075 wait_for_sigstop (but will). */
1076 new_lwp
->stop_expected
= 1;
1081 /* Callback for linux_proc_attach_tgid_threads. Attach to PTID if not
1082 already attached. Returns true if a new LWP is found, false
1086 attach_proc_task_lwp_callback (ptid_t ptid
)
1088 /* Is this a new thread? */
1089 if (find_thread_ptid (ptid
) == NULL
)
1091 int lwpid
= ptid
.lwp ();
1095 debug_printf ("Found new lwp %d\n", lwpid
);
1097 err
= the_linux_target
->attach_lwp (ptid
);
1099 /* Be quiet if we simply raced with the thread exiting. EPERM
1100 is returned if the thread's task still exists, and is marked
1101 as exited or zombie, as well as other conditions, so in that
1102 case, confirm the status in /proc/PID/status. */
1104 || (err
== EPERM
&& linux_proc_pid_is_gone (lwpid
)))
1108 debug_printf ("Cannot attach to lwp %d: "
1109 "thread is gone (%d: %s)\n",
1110 lwpid
, err
, safe_strerror (err
));
1116 = linux_ptrace_attach_fail_reason_string (ptid
, err
);
1118 warning (_("Cannot attach to lwp %d: %s"), lwpid
, reason
.c_str ());
1126 static void async_file_mark (void);
1128 /* Attach to PID. If PID is the tgid, attach to it and all
1132 linux_process_target::attach (unsigned long pid
)
1134 struct process_info
*proc
;
1135 struct thread_info
*initial_thread
;
1136 ptid_t ptid
= ptid_t (pid
, pid
);
1139 proc
= add_linux_process (pid
, 1);
1141 /* Attach to PID. We will check for other threads
1143 err
= attach_lwp (ptid
);
1146 remove_process (proc
);
1148 std::string reason
= linux_ptrace_attach_fail_reason_string (ptid
, err
);
1149 error ("Cannot attach to process %ld: %s", pid
, reason
.c_str ());
1152 /* Don't ignore the initial SIGSTOP if we just attached to this
1153 process. It will be collected by wait shortly. */
1154 initial_thread
= find_thread_ptid (ptid_t (pid
, pid
));
1155 initial_thread
->last_resume_kind
= resume_stop
;
1157 /* We must attach to every LWP. If /proc is mounted, use that to
1158 find them now. On the one hand, the inferior may be using raw
1159 clone instead of using pthreads. On the other hand, even if it
1160 is using pthreads, GDB may not be connected yet (thread_db needs
1161 to do symbol lookups, through qSymbol). Also, thread_db walks
1162 structures in the inferior's address space to find the list of
1163 threads/LWPs, and those structures may well be corrupted. Note
1164 that once thread_db is loaded, we'll still use it to list threads
1165 and associate pthread info with each LWP. */
1166 linux_proc_attach_tgid_threads (pid
, attach_proc_task_lwp_callback
);
1168 /* GDB will shortly read the xml target description for this
1169 process, to figure out the process' architecture. But the target
1170 description is only filled in when the first process/thread in
1171 the thread group reports its initial PTRACE_ATTACH SIGSTOP. Do
1172 that now, otherwise, if GDB is fast enough, it could read the
1173 target description _before_ that initial stop. */
1176 struct lwp_info
*lwp
;
1178 ptid_t pid_ptid
= ptid_t (pid
);
1180 lwpid
= wait_for_event_filtered (pid_ptid
, pid_ptid
, &wstat
, __WALL
);
1181 gdb_assert (lwpid
> 0);
1183 lwp
= find_lwp_pid (ptid_t (lwpid
));
1185 if (!WIFSTOPPED (wstat
) || WSTOPSIG (wstat
) != SIGSTOP
)
1187 lwp
->status_pending_p
= 1;
1188 lwp
->status_pending
= wstat
;
1191 initial_thread
->last_resume_kind
= resume_continue
;
1195 gdb_assert (proc
->tdesc
!= NULL
);
1202 last_thread_of_process_p (int pid
)
1204 bool seen_one
= false;
1206 thread_info
*thread
= find_thread (pid
, [&] (thread_info
*thr_arg
)
1210 /* This is the first thread of this process we see. */
1216 /* This is the second thread of this process we see. */
1221 return thread
== NULL
;
1227 linux_kill_one_lwp (struct lwp_info
*lwp
)
1229 struct thread_info
*thr
= get_lwp_thread (lwp
);
1230 int pid
= lwpid_of (thr
);
1232 /* PTRACE_KILL is unreliable. After stepping into a signal handler,
1233 there is no signal context, and ptrace(PTRACE_KILL) (or
1234 ptrace(PTRACE_CONT, SIGKILL), pretty much the same) acts like
1235 ptrace(CONT, pid, 0,0) and just resumes the tracee. A better
1236 alternative is to kill with SIGKILL. We only need one SIGKILL
1237 per process, not one for each thread. But since we still support
1238 support debugging programs using raw clone without CLONE_THREAD,
1239 we send one for each thread. For years, we used PTRACE_KILL
1240 only, so we're being a bit paranoid about some old kernels where
1241 PTRACE_KILL might work better (dubious if there are any such, but
1242 that's why it's paranoia), so we try SIGKILL first, PTRACE_KILL
1243 second, and so we're fine everywhere. */
1246 kill_lwp (pid
, SIGKILL
);
1249 int save_errno
= errno
;
1251 debug_printf ("LKL: kill_lwp (SIGKILL) %s, 0, 0 (%s)\n",
1252 target_pid_to_str (ptid_of (thr
)).c_str (),
1253 save_errno
? safe_strerror (save_errno
) : "OK");
1257 ptrace (PTRACE_KILL
, pid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
1260 int save_errno
= errno
;
1262 debug_printf ("LKL: PTRACE_KILL %s, 0, 0 (%s)\n",
1263 target_pid_to_str (ptid_of (thr
)).c_str (),
1264 save_errno
? safe_strerror (save_errno
) : "OK");
1268 /* Kill LWP and wait for it to die. */
1271 kill_wait_lwp (struct lwp_info
*lwp
)
1273 struct thread_info
*thr
= get_lwp_thread (lwp
);
1274 int pid
= ptid_of (thr
).pid ();
1275 int lwpid
= ptid_of (thr
).lwp ();
1280 debug_printf ("kwl: killing lwp %d, for pid: %d\n", lwpid
, pid
);
1284 linux_kill_one_lwp (lwp
);
1286 /* Make sure it died. Notes:
1288 - The loop is most likely unnecessary.
1290 - We don't use wait_for_event as that could delete lwps
1291 while we're iterating over them. We're not interested in
1292 any pending status at this point, only in making sure all
1293 wait status on the kernel side are collected until the
1296 - We don't use __WALL here as the __WALL emulation relies on
1297 SIGCHLD, and killing a stopped process doesn't generate
1298 one, nor an exit status.
1300 res
= my_waitpid (lwpid
, &wstat
, 0);
1301 if (res
== -1 && errno
== ECHILD
)
1302 res
= my_waitpid (lwpid
, &wstat
, __WCLONE
);
1303 } while (res
> 0 && WIFSTOPPED (wstat
));
1305 /* Even if it was stopped, the child may have already disappeared.
1306 E.g., if it was killed by SIGKILL. */
1307 if (res
< 0 && errno
!= ECHILD
)
1308 perror_with_name ("kill_wait_lwp");
1311 /* Callback for `for_each_thread'. Kills an lwp of a given process,
1312 except the leader. */
1315 kill_one_lwp_callback (thread_info
*thread
, int pid
)
1317 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1319 /* We avoid killing the first thread here, because of a Linux kernel (at
1320 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
1321 the children get a chance to be reaped, it will remain a zombie
1324 if (lwpid_of (thread
) == pid
)
1327 debug_printf ("lkop: is last of process %s\n",
1328 target_pid_to_str (thread
->id
).c_str ());
1332 kill_wait_lwp (lwp
);
1336 linux_process_target::kill (process_info
*process
)
1338 int pid
= process
->pid
;
1340 /* If we're killing a running inferior, make sure it is stopped
1341 first, as PTRACE_KILL will not work otherwise. */
1342 stop_all_lwps (0, NULL
);
1344 for_each_thread (pid
, [&] (thread_info
*thread
)
1346 kill_one_lwp_callback (thread
, pid
);
1349 /* See the comment in linux_kill_one_lwp. We did not kill the first
1350 thread in the list, so do so now. */
1351 lwp_info
*lwp
= find_lwp_pid (ptid_t (pid
));
1356 debug_printf ("lk_1: cannot find lwp for pid: %d\n",
1360 kill_wait_lwp (lwp
);
1364 /* Since we presently can only stop all lwps of all processes, we
1365 need to unstop lwps of other processes. */
1366 unstop_all_lwps (0, NULL
);
1370 /* Get pending signal of THREAD, for detaching purposes. This is the
1371 signal the thread last stopped for, which we need to deliver to the
1372 thread when detaching, otherwise, it'd be suppressed/lost. */
1375 get_detach_signal (struct thread_info
*thread
)
1377 client_state
&cs
= get_client_state ();
1378 enum gdb_signal signo
= GDB_SIGNAL_0
;
1380 struct lwp_info
*lp
= get_thread_lwp (thread
);
1382 if (lp
->status_pending_p
)
1383 status
= lp
->status_pending
;
1386 /* If the thread had been suspended by gdbserver, and it stopped
1387 cleanly, then it'll have stopped with SIGSTOP. But we don't
1388 want to deliver that SIGSTOP. */
1389 if (thread
->last_status
.kind () != TARGET_WAITKIND_STOPPED
1390 || thread
->last_status
.sig () == GDB_SIGNAL_0
)
1393 /* Otherwise, we may need to deliver the signal we
1395 status
= lp
->last_status
;
1398 if (!WIFSTOPPED (status
))
1401 debug_printf ("GPS: lwp %s hasn't stopped: no pending signal\n",
1402 target_pid_to_str (ptid_of (thread
)).c_str ());
1406 /* Extended wait statuses aren't real SIGTRAPs. */
1407 if (WSTOPSIG (status
) == SIGTRAP
&& linux_is_extended_waitstatus (status
))
1410 debug_printf ("GPS: lwp %s had stopped with extended "
1411 "status: no pending signal\n",
1412 target_pid_to_str (ptid_of (thread
)).c_str ());
1416 signo
= gdb_signal_from_host (WSTOPSIG (status
));
1418 if (cs
.program_signals_p
&& !cs
.program_signals
[signo
])
1421 debug_printf ("GPS: lwp %s had signal %s, but it is in nopass state\n",
1422 target_pid_to_str (ptid_of (thread
)).c_str (),
1423 gdb_signal_to_string (signo
));
1426 else if (!cs
.program_signals_p
1427 /* If we have no way to know which signals GDB does not
1428 want to have passed to the program, assume
1429 SIGTRAP/SIGINT, which is GDB's default. */
1430 && (signo
== GDB_SIGNAL_TRAP
|| signo
== GDB_SIGNAL_INT
))
1433 debug_printf ("GPS: lwp %s had signal %s, "
1434 "but we don't know if we should pass it. "
1435 "Default to not.\n",
1436 target_pid_to_str (ptid_of (thread
)).c_str (),
1437 gdb_signal_to_string (signo
));
1443 debug_printf ("GPS: lwp %s has pending signal %s: delivering it.\n",
1444 target_pid_to_str (ptid_of (thread
)).c_str (),
1445 gdb_signal_to_string (signo
));
1447 return WSTOPSIG (status
);
1452 linux_process_target::detach_one_lwp (lwp_info
*lwp
)
1454 struct thread_info
*thread
= get_lwp_thread (lwp
);
1458 /* If there is a pending SIGSTOP, get rid of it. */
1459 if (lwp
->stop_expected
)
1462 debug_printf ("Sending SIGCONT to %s\n",
1463 target_pid_to_str (ptid_of (thread
)).c_str ());
1465 kill_lwp (lwpid_of (thread
), SIGCONT
);
1466 lwp
->stop_expected
= 0;
1469 /* Pass on any pending signal for this thread. */
1470 sig
= get_detach_signal (thread
);
1472 /* Preparing to resume may try to write registers, and fail if the
1473 lwp is zombie. If that happens, ignore the error. We'll handle
1474 it below, when detach fails with ESRCH. */
1477 /* Flush any pending changes to the process's registers. */
1478 regcache_invalidate_thread (thread
);
1480 /* Finally, let it resume. */
1481 low_prepare_to_resume (lwp
);
1483 catch (const gdb_exception_error
&ex
)
1485 if (!check_ptrace_stopped_lwp_gone (lwp
))
1489 lwpid
= lwpid_of (thread
);
1490 if (ptrace (PTRACE_DETACH
, lwpid
, (PTRACE_TYPE_ARG3
) 0,
1491 (PTRACE_TYPE_ARG4
) (long) sig
) < 0)
1493 int save_errno
= errno
;
1495 /* We know the thread exists, so ESRCH must mean the lwp is
1496 zombie. This can happen if one of the already-detached
1497 threads exits the whole thread group. In that case we're
1498 still attached, and must reap the lwp. */
1499 if (save_errno
== ESRCH
)
1503 ret
= my_waitpid (lwpid
, &status
, __WALL
);
1506 warning (_("Couldn't reap LWP %d while detaching: %s"),
1507 lwpid
, safe_strerror (errno
));
1509 else if (!WIFEXITED (status
) && !WIFSIGNALED (status
))
1511 warning (_("Reaping LWP %d while detaching "
1512 "returned unexpected status 0x%x"),
1518 error (_("Can't detach %s: %s"),
1519 target_pid_to_str (ptid_of (thread
)).c_str (),
1520 safe_strerror (save_errno
));
1523 else if (debug_threads
)
1525 debug_printf ("PTRACE_DETACH (%s, %s, 0) (OK)\n",
1526 target_pid_to_str (ptid_of (thread
)).c_str (),
1534 linux_process_target::detach (process_info
*process
)
1536 struct lwp_info
*main_lwp
;
1538 /* As there's a step over already in progress, let it finish first,
1539 otherwise nesting a stabilize_threads operation on top gets real
1541 complete_ongoing_step_over ();
1543 /* Stop all threads before detaching. First, ptrace requires that
1544 the thread is stopped to successfully detach. Second, thread_db
1545 may need to uninstall thread event breakpoints from memory, which
1546 only works with a stopped process anyway. */
1547 stop_all_lwps (0, NULL
);
1549 #ifdef USE_THREAD_DB
1550 thread_db_detach (process
);
1553 /* Stabilize threads (move out of jump pads). */
1554 target_stabilize_threads ();
1556 /* Detach from the clone lwps first. If the thread group exits just
1557 while we're detaching, we must reap the clone lwps before we're
1558 able to reap the leader. */
1559 for_each_thread (process
->pid
, [this] (thread_info
*thread
)
1561 /* We don't actually detach from the thread group leader just yet.
1562 If the thread group exits, we must reap the zombie clone lwps
1563 before we're able to reap the leader. */
1564 if (thread
->id
.pid () == thread
->id
.lwp ())
1567 lwp_info
*lwp
= get_thread_lwp (thread
);
1568 detach_one_lwp (lwp
);
1571 main_lwp
= find_lwp_pid (ptid_t (process
->pid
));
1572 detach_one_lwp (main_lwp
);
1576 /* Since we presently can only stop all lwps of all processes, we
1577 need to unstop lwps of other processes. */
1578 unstop_all_lwps (0, NULL
);
1582 /* Remove all LWPs that belong to process PROC from the lwp list. */
1585 linux_process_target::mourn (process_info
*process
)
1587 struct process_info_private
*priv
;
1589 #ifdef USE_THREAD_DB
1590 thread_db_mourn (process
);
1593 for_each_thread (process
->pid
, [this] (thread_info
*thread
)
1595 delete_lwp (get_thread_lwp (thread
));
1598 /* Freeing all private data. */
1599 priv
= process
->priv
;
1600 low_delete_process (priv
->arch_private
);
1602 process
->priv
= NULL
;
1604 remove_process (process
);
1608 linux_process_target::join (int pid
)
1613 ret
= my_waitpid (pid
, &status
, 0);
1614 if (WIFEXITED (status
) || WIFSIGNALED (status
))
1616 } while (ret
!= -1 || errno
!= ECHILD
);
1619 /* Return true if the given thread is still alive. */
1622 linux_process_target::thread_alive (ptid_t ptid
)
1624 struct lwp_info
*lwp
= find_lwp_pid (ptid
);
1626 /* We assume we always know if a thread exits. If a whole process
1627 exited but we still haven't been able to report it to GDB, we'll
1628 hold on to the last lwp of the dead process. */
1630 return !lwp_is_marked_dead (lwp
);
1636 linux_process_target::thread_still_has_status_pending (thread_info
*thread
)
1638 struct lwp_info
*lp
= get_thread_lwp (thread
);
1640 if (!lp
->status_pending_p
)
1643 if (thread
->last_resume_kind
!= resume_stop
1644 && (lp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
1645 || lp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
1647 struct thread_info
*saved_thread
;
1651 gdb_assert (lp
->last_status
!= 0);
1655 saved_thread
= current_thread
;
1656 current_thread
= thread
;
1658 if (pc
!= lp
->stop_pc
)
1661 debug_printf ("PC of %ld changed\n",
1666 #if !USE_SIGTRAP_SIGINFO
1667 else if (lp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
1668 && !low_breakpoint_at (pc
))
1671 debug_printf ("previous SW breakpoint of %ld gone\n",
1675 else if (lp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
1676 && !hardware_breakpoint_inserted_here (pc
))
1679 debug_printf ("previous HW breakpoint of %ld gone\n",
1685 current_thread
= saved_thread
;
1690 debug_printf ("discarding pending breakpoint status\n");
1691 lp
->status_pending_p
= 0;
1699 /* Returns true if LWP is resumed from the client's perspective. */
1702 lwp_resumed (struct lwp_info
*lwp
)
1704 struct thread_info
*thread
= get_lwp_thread (lwp
);
1706 if (thread
->last_resume_kind
!= resume_stop
)
1709 /* Did gdb send us a `vCont;t', but we haven't reported the
1710 corresponding stop to gdb yet? If so, the thread is still
1711 resumed/running from gdb's perspective. */
1712 if (thread
->last_resume_kind
== resume_stop
1713 && thread
->last_status
.kind () == TARGET_WAITKIND_IGNORE
)
1720 linux_process_target::status_pending_p_callback (thread_info
*thread
,
1723 struct lwp_info
*lp
= get_thread_lwp (thread
);
1725 /* Check if we're only interested in events from a specific process
1726 or a specific LWP. */
1727 if (!thread
->id
.matches (ptid
))
1730 if (!lwp_resumed (lp
))
1733 if (lp
->status_pending_p
1734 && !thread_still_has_status_pending (thread
))
1736 resume_one_lwp (lp
, lp
->stepping
, GDB_SIGNAL_0
, NULL
);
1740 return lp
->status_pending_p
;
1744 find_lwp_pid (ptid_t ptid
)
1746 thread_info
*thread
= find_thread ([&] (thread_info
*thr_arg
)
1748 int lwp
= ptid
.lwp () != 0 ? ptid
.lwp () : ptid
.pid ();
1749 return thr_arg
->id
.lwp () == lwp
;
1755 return get_thread_lwp (thread
);
1758 /* Return the number of known LWPs in the tgid given by PID. */
1765 for_each_thread (pid
, [&] (thread_info
*thread
)
1773 /* See nat/linux-nat.h. */
1776 iterate_over_lwps (ptid_t filter
,
1777 gdb::function_view
<iterate_over_lwps_ftype
> callback
)
1779 thread_info
*thread
= find_thread (filter
, [&] (thread_info
*thr_arg
)
1781 lwp_info
*lwp
= get_thread_lwp (thr_arg
);
1783 return callback (lwp
);
1789 return get_thread_lwp (thread
);
1793 linux_process_target::check_zombie_leaders ()
1795 for_each_process ([this] (process_info
*proc
) {
1796 pid_t leader_pid
= pid_of (proc
);
1797 struct lwp_info
*leader_lp
;
1799 leader_lp
= find_lwp_pid (ptid_t (leader_pid
));
1802 debug_printf ("leader_pid=%d, leader_lp!=NULL=%d, "
1803 "num_lwps=%d, zombie=%d\n",
1804 leader_pid
, leader_lp
!= NULL
, num_lwps (leader_pid
),
1805 linux_proc_pid_is_zombie (leader_pid
));
1807 if (leader_lp
!= NULL
&& !leader_lp
->stopped
1808 /* Check if there are other threads in the group, as we may
1809 have raced with the inferior simply exiting. */
1810 && !last_thread_of_process_p (leader_pid
)
1811 && linux_proc_pid_is_zombie (leader_pid
))
1813 /* A leader zombie can mean one of two things:
1815 - It exited, and there's an exit status pending
1816 available, or only the leader exited (not the whole
1817 program). In the latter case, we can't waitpid the
1818 leader's exit status until all other threads are gone.
1820 - There are 3 or more threads in the group, and a thread
1821 other than the leader exec'd. On an exec, the Linux
1822 kernel destroys all other threads (except the execing
1823 one) in the thread group, and resets the execing thread's
1824 tid to the tgid. No exit notification is sent for the
1825 execing thread -- from the ptracer's perspective, it
1826 appears as though the execing thread just vanishes.
1827 Until we reap all other threads except the leader and the
1828 execing thread, the leader will be zombie, and the
1829 execing thread will be in `D (disc sleep)'. As soon as
1830 all other threads are reaped, the execing thread changes
1831 it's tid to the tgid, and the previous (zombie) leader
1832 vanishes, giving place to the "new" leader. We could try
1833 distinguishing the exit and exec cases, by waiting once
1834 more, and seeing if something comes out, but it doesn't
1835 sound useful. The previous leader _does_ go away, and
1836 we'll re-add the new one once we see the exec event
1837 (which is just the same as what would happen if the
1838 previous leader did exit voluntarily before some other
1842 debug_printf ("CZL: Thread group leader %d zombie "
1843 "(it exited, or another thread execd).\n",
1846 delete_lwp (leader_lp
);
1851 /* Callback for `find_thread'. Returns the first LWP that is not
1855 not_stopped_callback (thread_info
*thread
, ptid_t filter
)
1857 if (!thread
->id
.matches (filter
))
1860 lwp_info
*lwp
= get_thread_lwp (thread
);
1862 return !lwp
->stopped
;
1865 /* Increment LWP's suspend count. */
1868 lwp_suspended_inc (struct lwp_info
*lwp
)
1872 if (debug_threads
&& lwp
->suspended
> 4)
1874 struct thread_info
*thread
= get_lwp_thread (lwp
);
1876 debug_printf ("LWP %ld has a suspiciously high suspend count,"
1877 " suspended=%d\n", lwpid_of (thread
), lwp
->suspended
);
1881 /* Decrement LWP's suspend count. */
1884 lwp_suspended_decr (struct lwp_info
*lwp
)
1888 if (lwp
->suspended
< 0)
1890 struct thread_info
*thread
= get_lwp_thread (lwp
);
1892 internal_error (__FILE__
, __LINE__
,
1893 "unsuspend LWP %ld, suspended=%d\n", lwpid_of (thread
),
1898 /* This function should only be called if the LWP got a SIGTRAP.
1900 Handle any tracepoint steps or hits. Return true if a tracepoint
1901 event was handled, 0 otherwise. */
1904 handle_tracepoints (struct lwp_info
*lwp
)
1906 struct thread_info
*tinfo
= get_lwp_thread (lwp
);
1907 int tpoint_related_event
= 0;
1909 gdb_assert (lwp
->suspended
== 0);
1911 /* If this tracepoint hit causes a tracing stop, we'll immediately
1912 uninsert tracepoints. To do this, we temporarily pause all
1913 threads, unpatch away, and then unpause threads. We need to make
1914 sure the unpausing doesn't resume LWP too. */
1915 lwp_suspended_inc (lwp
);
1917 /* And we need to be sure that any all-threads-stopping doesn't try
1918 to move threads out of the jump pads, as it could deadlock the
1919 inferior (LWP could be in the jump pad, maybe even holding the
1922 /* Do any necessary step collect actions. */
1923 tpoint_related_event
|= tracepoint_finished_step (tinfo
, lwp
->stop_pc
);
1925 tpoint_related_event
|= handle_tracepoint_bkpts (tinfo
, lwp
->stop_pc
);
1927 /* See if we just hit a tracepoint and do its main collect
1929 tpoint_related_event
|= tracepoint_was_hit (tinfo
, lwp
->stop_pc
);
1931 lwp_suspended_decr (lwp
);
1933 gdb_assert (lwp
->suspended
== 0);
1934 gdb_assert (!stabilizing_threads
1935 || (lwp
->collecting_fast_tracepoint
1936 != fast_tpoint_collect_result::not_collecting
));
1938 if (tpoint_related_event
)
1941 debug_printf ("got a tracepoint event\n");
1948 fast_tpoint_collect_result
1949 linux_process_target::linux_fast_tracepoint_collecting
1950 (lwp_info
*lwp
, fast_tpoint_collect_status
*status
)
1952 CORE_ADDR thread_area
;
1953 struct thread_info
*thread
= get_lwp_thread (lwp
);
1955 /* Get the thread area address. This is used to recognize which
1956 thread is which when tracing with the in-process agent library.
1957 We don't read anything from the address, and treat it as opaque;
1958 it's the address itself that we assume is unique per-thread. */
1959 if (low_get_thread_area (lwpid_of (thread
), &thread_area
) == -1)
1960 return fast_tpoint_collect_result::not_collecting
;
1962 return fast_tracepoint_collecting (thread_area
, lwp
->stop_pc
, status
);
1966 linux_process_target::low_get_thread_area (int lwpid
, CORE_ADDR
*addrp
)
1972 linux_process_target::maybe_move_out_of_jump_pad (lwp_info
*lwp
, int *wstat
)
1974 struct thread_info
*saved_thread
;
1976 saved_thread
= current_thread
;
1977 current_thread
= get_lwp_thread (lwp
);
1980 || (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) != SIGTRAP
))
1981 && supports_fast_tracepoints ()
1982 && agent_loaded_p ())
1984 struct fast_tpoint_collect_status status
;
1987 debug_printf ("Checking whether LWP %ld needs to move out of the "
1989 lwpid_of (current_thread
));
1991 fast_tpoint_collect_result r
1992 = linux_fast_tracepoint_collecting (lwp
, &status
);
1995 || (WSTOPSIG (*wstat
) != SIGILL
1996 && WSTOPSIG (*wstat
) != SIGFPE
1997 && WSTOPSIG (*wstat
) != SIGSEGV
1998 && WSTOPSIG (*wstat
) != SIGBUS
))
2000 lwp
->collecting_fast_tracepoint
= r
;
2002 if (r
!= fast_tpoint_collect_result::not_collecting
)
2004 if (r
== fast_tpoint_collect_result::before_insn
2005 && lwp
->exit_jump_pad_bkpt
== NULL
)
2007 /* Haven't executed the original instruction yet.
2008 Set breakpoint there, and wait till it's hit,
2009 then single-step until exiting the jump pad. */
2010 lwp
->exit_jump_pad_bkpt
2011 = set_breakpoint_at (status
.adjusted_insn_addr
, NULL
);
2015 debug_printf ("Checking whether LWP %ld needs to move out of "
2016 "the jump pad...it does\n",
2017 lwpid_of (current_thread
));
2018 current_thread
= saved_thread
;
2025 /* If we get a synchronous signal while collecting, *and*
2026 while executing the (relocated) original instruction,
2027 reset the PC to point at the tpoint address, before
2028 reporting to GDB. Otherwise, it's an IPA lib bug: just
2029 report the signal to GDB, and pray for the best. */
2031 lwp
->collecting_fast_tracepoint
2032 = fast_tpoint_collect_result::not_collecting
;
2034 if (r
!= fast_tpoint_collect_result::not_collecting
2035 && (status
.adjusted_insn_addr
<= lwp
->stop_pc
2036 && lwp
->stop_pc
< status
.adjusted_insn_addr_end
))
2039 struct regcache
*regcache
;
2041 /* The si_addr on a few signals references the address
2042 of the faulting instruction. Adjust that as
2044 if ((WSTOPSIG (*wstat
) == SIGILL
2045 || WSTOPSIG (*wstat
) == SIGFPE
2046 || WSTOPSIG (*wstat
) == SIGBUS
2047 || WSTOPSIG (*wstat
) == SIGSEGV
)
2048 && ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
2049 (PTRACE_TYPE_ARG3
) 0, &info
) == 0
2050 /* Final check just to make sure we don't clobber
2051 the siginfo of non-kernel-sent signals. */
2052 && (uintptr_t) info
.si_addr
== lwp
->stop_pc
)
2054 info
.si_addr
= (void *) (uintptr_t) status
.tpoint_addr
;
2055 ptrace (PTRACE_SETSIGINFO
, lwpid_of (current_thread
),
2056 (PTRACE_TYPE_ARG3
) 0, &info
);
2059 regcache
= get_thread_regcache (current_thread
, 1);
2060 low_set_pc (regcache
, status
.tpoint_addr
);
2061 lwp
->stop_pc
= status
.tpoint_addr
;
2063 /* Cancel any fast tracepoint lock this thread was
2065 force_unlock_trace_buffer ();
2068 if (lwp
->exit_jump_pad_bkpt
!= NULL
)
2071 debug_printf ("Cancelling fast exit-jump-pad: removing bkpt. "
2072 "stopping all threads momentarily.\n");
2074 stop_all_lwps (1, lwp
);
2076 delete_breakpoint (lwp
->exit_jump_pad_bkpt
);
2077 lwp
->exit_jump_pad_bkpt
= NULL
;
2079 unstop_all_lwps (1, lwp
);
2081 gdb_assert (lwp
->suspended
>= 0);
2087 debug_printf ("Checking whether LWP %ld needs to move out of the "
2089 lwpid_of (current_thread
));
2091 current_thread
= saved_thread
;
2095 /* Enqueue one signal in the "signals to report later when out of the
2099 enqueue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
2101 struct thread_info
*thread
= get_lwp_thread (lwp
);
2104 debug_printf ("Deferring signal %d for LWP %ld.\n",
2105 WSTOPSIG (*wstat
), lwpid_of (thread
));
2109 for (const auto &sig
: lwp
->pending_signals_to_report
)
2110 debug_printf (" Already queued %d\n",
2113 debug_printf (" (no more currently queued signals)\n");
2116 /* Don't enqueue non-RT signals if they are already in the deferred
2117 queue. (SIGSTOP being the easiest signal to see ending up here
2119 if (WSTOPSIG (*wstat
) < __SIGRTMIN
)
2121 for (const auto &sig
: lwp
->pending_signals_to_report
)
2123 if (sig
.signal
== WSTOPSIG (*wstat
))
2126 debug_printf ("Not requeuing already queued non-RT signal %d"
2135 lwp
->pending_signals_to_report
.emplace_back (WSTOPSIG (*wstat
));
2137 ptrace (PTRACE_GETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
2138 &lwp
->pending_signals_to_report
.back ().info
);
2141 /* Dequeue one signal from the "signals to report later when out of
2142 the jump pad" list. */
2145 dequeue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
2147 struct thread_info
*thread
= get_lwp_thread (lwp
);
2149 if (!lwp
->pending_signals_to_report
.empty ())
2151 const pending_signal
&p_sig
= lwp
->pending_signals_to_report
.front ();
2153 *wstat
= W_STOPCODE (p_sig
.signal
);
2154 if (p_sig
.info
.si_signo
!= 0)
2155 ptrace (PTRACE_SETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
2158 lwp
->pending_signals_to_report
.pop_front ();
2161 debug_printf ("Reporting deferred signal %d for LWP %ld.\n",
2162 WSTOPSIG (*wstat
), lwpid_of (thread
));
2166 for (const auto &sig
: lwp
->pending_signals_to_report
)
2167 debug_printf (" Still queued %d\n",
2170 debug_printf (" (no more queued signals)\n");
2180 linux_process_target::check_stopped_by_watchpoint (lwp_info
*child
)
2182 struct thread_info
*saved_thread
= current_thread
;
2183 current_thread
= get_lwp_thread (child
);
2185 if (low_stopped_by_watchpoint ())
2187 child
->stop_reason
= TARGET_STOPPED_BY_WATCHPOINT
;
2188 child
->stopped_data_address
= low_stopped_data_address ();
2191 current_thread
= saved_thread
;
2193 return child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
;
2197 linux_process_target::low_stopped_by_watchpoint ()
2203 linux_process_target::low_stopped_data_address ()
2208 /* Return the ptrace options that we want to try to enable. */
2211 linux_low_ptrace_options (int attached
)
2213 client_state
&cs
= get_client_state ();
2217 options
|= PTRACE_O_EXITKILL
;
2219 if (cs
.report_fork_events
)
2220 options
|= PTRACE_O_TRACEFORK
;
2222 if (cs
.report_vfork_events
)
2223 options
|= (PTRACE_O_TRACEVFORK
| PTRACE_O_TRACEVFORKDONE
);
2225 if (cs
.report_exec_events
)
2226 options
|= PTRACE_O_TRACEEXEC
;
2228 options
|= PTRACE_O_TRACESYSGOOD
;
2234 linux_process_target::filter_event (int lwpid
, int wstat
)
2236 client_state
&cs
= get_client_state ();
2237 struct lwp_info
*child
;
2238 struct thread_info
*thread
;
2239 int have_stop_pc
= 0;
2241 child
= find_lwp_pid (ptid_t (lwpid
));
2243 /* Check for stop events reported by a process we didn't already
2244 know about - anything not already in our LWP list.
2246 If we're expecting to receive stopped processes after
2247 fork, vfork, and clone events, then we'll just add the
2248 new one to our list and go back to waiting for the event
2249 to be reported - the stopped process might be returned
2250 from waitpid before or after the event is.
2252 But note the case of a non-leader thread exec'ing after the
2253 leader having exited, and gone from our lists (because
2254 check_zombie_leaders deleted it). The non-leader thread
2255 changes its tid to the tgid. */
2257 if (WIFSTOPPED (wstat
) && child
== NULL
&& WSTOPSIG (wstat
) == SIGTRAP
2258 && linux_ptrace_get_extended_event (wstat
) == PTRACE_EVENT_EXEC
)
2262 /* A multi-thread exec after we had seen the leader exiting. */
2265 debug_printf ("LLW: Re-adding thread group leader LWP %d"
2266 "after exec.\n", lwpid
);
2269 child_ptid
= ptid_t (lwpid
, lwpid
);
2270 child
= add_lwp (child_ptid
);
2272 current_thread
= child
->thread
;
2275 /* If we didn't find a process, one of two things presumably happened:
2276 - A process we started and then detached from has exited. Ignore it.
2277 - A process we are controlling has forked and the new child's stop
2278 was reported to us by the kernel. Save its PID. */
2279 if (child
== NULL
&& WIFSTOPPED (wstat
))
2281 add_to_pid_list (&stopped_pids
, lwpid
, wstat
);
2284 else if (child
== NULL
)
2287 thread
= get_lwp_thread (child
);
2291 child
->last_status
= wstat
;
2293 /* Check if the thread has exited. */
2294 if ((WIFEXITED (wstat
) || WIFSIGNALED (wstat
)))
2297 debug_printf ("LLFE: %d exited.\n", lwpid
);
2299 if (finish_step_over (child
))
2301 /* Unsuspend all other LWPs, and set them back running again. */
2302 unsuspend_all_lwps (child
);
2305 /* If there is at least one more LWP, then the exit signal was
2306 not the end of the debugged application and should be
2307 ignored, unless GDB wants to hear about thread exits. */
2308 if (cs
.report_thread_events
2309 || last_thread_of_process_p (pid_of (thread
)))
2311 /* Since events are serialized to GDB core, and we can't
2312 report this one right now. Leave the status pending for
2313 the next time we're able to report it. */
2314 mark_lwp_dead (child
, wstat
);
2324 gdb_assert (WIFSTOPPED (wstat
));
2326 if (WIFSTOPPED (wstat
))
2328 struct process_info
*proc
;
2330 /* Architecture-specific setup after inferior is running. */
2331 proc
= find_process_pid (pid_of (thread
));
2332 if (proc
->tdesc
== NULL
)
2336 /* This needs to happen after we have attached to the
2337 inferior and it is stopped for the first time, but
2338 before we access any inferior registers. */
2339 arch_setup_thread (thread
);
2343 /* The process is started, but GDBserver will do
2344 architecture-specific setup after the program stops at
2345 the first instruction. */
2346 child
->status_pending_p
= 1;
2347 child
->status_pending
= wstat
;
2353 if (WIFSTOPPED (wstat
) && child
->must_set_ptrace_flags
)
2355 struct process_info
*proc
= find_process_pid (pid_of (thread
));
2356 int options
= linux_low_ptrace_options (proc
->attached
);
2358 linux_enable_event_reporting (lwpid
, options
);
2359 child
->must_set_ptrace_flags
= 0;
2362 /* Always update syscall_state, even if it will be filtered later. */
2363 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SYSCALL_SIGTRAP
)
2365 child
->syscall_state
2366 = (child
->syscall_state
== TARGET_WAITKIND_SYSCALL_ENTRY
2367 ? TARGET_WAITKIND_SYSCALL_RETURN
2368 : TARGET_WAITKIND_SYSCALL_ENTRY
);
2372 /* Almost all other ptrace-stops are known to be outside of system
2373 calls, with further exceptions in handle_extended_wait. */
2374 child
->syscall_state
= TARGET_WAITKIND_IGNORE
;
2377 /* Be careful to not overwrite stop_pc until save_stop_reason is
2379 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGTRAP
2380 && linux_is_extended_waitstatus (wstat
))
2382 child
->stop_pc
= get_pc (child
);
2383 if (handle_extended_wait (&child
, wstat
))
2385 /* The event has been handled, so just return without
2391 if (linux_wstatus_maybe_breakpoint (wstat
))
2393 if (save_stop_reason (child
))
2398 child
->stop_pc
= get_pc (child
);
2400 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGSTOP
2401 && child
->stop_expected
)
2404 debug_printf ("Expected stop.\n");
2405 child
->stop_expected
= 0;
2407 if (thread
->last_resume_kind
== resume_stop
)
2409 /* We want to report the stop to the core. Treat the
2410 SIGSTOP as a normal event. */
2412 debug_printf ("LLW: resume_stop SIGSTOP caught for %s.\n",
2413 target_pid_to_str (ptid_of (thread
)).c_str ());
2415 else if (stopping_threads
!= NOT_STOPPING_THREADS
)
2417 /* Stopping threads. We don't want this SIGSTOP to end up
2420 debug_printf ("LLW: SIGSTOP caught for %s "
2421 "while stopping threads.\n",
2422 target_pid_to_str (ptid_of (thread
)).c_str ());
2427 /* This is a delayed SIGSTOP. Filter out the event. */
2429 debug_printf ("LLW: %s %s, 0, 0 (discard delayed SIGSTOP)\n",
2430 child
->stepping
? "step" : "continue",
2431 target_pid_to_str (ptid_of (thread
)).c_str ());
2433 resume_one_lwp (child
, child
->stepping
, 0, NULL
);
2438 child
->status_pending_p
= 1;
2439 child
->status_pending
= wstat
;
2444 linux_process_target::maybe_hw_step (thread_info
*thread
)
2446 if (supports_hardware_single_step ())
2450 /* GDBserver must insert single-step breakpoint for software
2452 gdb_assert (has_single_step_breakpoints (thread
));
2458 linux_process_target::resume_stopped_resumed_lwps (thread_info
*thread
)
2460 struct lwp_info
*lp
= get_thread_lwp (thread
);
2464 && !lp
->status_pending_p
2465 && thread
->last_status
.kind () == TARGET_WAITKIND_IGNORE
)
2469 if (thread
->last_resume_kind
== resume_step
)
2470 step
= maybe_hw_step (thread
);
2473 debug_printf ("RSRL: resuming stopped-resumed LWP %s at %s: step=%d\n",
2474 target_pid_to_str (ptid_of (thread
)).c_str (),
2475 paddress (lp
->stop_pc
),
2478 resume_one_lwp (lp
, step
, GDB_SIGNAL_0
, NULL
);
2483 linux_process_target::wait_for_event_filtered (ptid_t wait_ptid
,
2485 int *wstatp
, int options
)
2487 struct thread_info
*event_thread
;
2488 struct lwp_info
*event_child
, *requested_child
;
2489 sigset_t block_mask
, prev_mask
;
2492 /* N.B. event_thread points to the thread_info struct that contains
2493 event_child. Keep them in sync. */
2494 event_thread
= NULL
;
2496 requested_child
= NULL
;
2498 /* Check for a lwp with a pending status. */
2500 if (filter_ptid
== minus_one_ptid
|| filter_ptid
.is_pid ())
2502 event_thread
= find_thread_in_random ([&] (thread_info
*thread
)
2504 return status_pending_p_callback (thread
, filter_ptid
);
2507 if (event_thread
!= NULL
)
2508 event_child
= get_thread_lwp (event_thread
);
2509 if (debug_threads
&& event_thread
)
2510 debug_printf ("Got a pending child %ld\n", lwpid_of (event_thread
));
2512 else if (filter_ptid
!= null_ptid
)
2514 requested_child
= find_lwp_pid (filter_ptid
);
2516 if (stopping_threads
== NOT_STOPPING_THREADS
2517 && requested_child
->status_pending_p
2518 && (requested_child
->collecting_fast_tracepoint
2519 != fast_tpoint_collect_result::not_collecting
))
2521 enqueue_one_deferred_signal (requested_child
,
2522 &requested_child
->status_pending
);
2523 requested_child
->status_pending_p
= 0;
2524 requested_child
->status_pending
= 0;
2525 resume_one_lwp (requested_child
, 0, 0, NULL
);
2528 if (requested_child
->suspended
2529 && requested_child
->status_pending_p
)
2531 internal_error (__FILE__
, __LINE__
,
2532 "requesting an event out of a"
2533 " suspended child?");
2536 if (requested_child
->status_pending_p
)
2538 event_child
= requested_child
;
2539 event_thread
= get_lwp_thread (event_child
);
2543 if (event_child
!= NULL
)
2546 debug_printf ("Got an event from pending child %ld (%04x)\n",
2547 lwpid_of (event_thread
), event_child
->status_pending
);
2548 *wstatp
= event_child
->status_pending
;
2549 event_child
->status_pending_p
= 0;
2550 event_child
->status_pending
= 0;
2551 current_thread
= event_thread
;
2552 return lwpid_of (event_thread
);
2555 /* But if we don't find a pending event, we'll have to wait.
2557 We only enter this loop if no process has a pending wait status.
2558 Thus any action taken in response to a wait status inside this
2559 loop is responding as soon as we detect the status, not after any
2562 /* Make sure SIGCHLD is blocked until the sigsuspend below. Block
2563 all signals while here. */
2564 sigfillset (&block_mask
);
2565 gdb_sigmask (SIG_BLOCK
, &block_mask
, &prev_mask
);
2567 /* Always pull all events out of the kernel. We'll randomly select
2568 an event LWP out of all that have events, to prevent
2570 while (event_child
== NULL
)
2574 /* Always use -1 and WNOHANG, due to couple of a kernel/ptrace
2577 - If the thread group leader exits while other threads in the
2578 thread group still exist, waitpid(TGID, ...) hangs. That
2579 waitpid won't return an exit status until the other threads
2580 in the group are reaped.
2582 - When a non-leader thread execs, that thread just vanishes
2583 without reporting an exit (so we'd hang if we waited for it
2584 explicitly in that case). The exec event is reported to
2587 ret
= my_waitpid (-1, wstatp
, options
| WNOHANG
);
2590 debug_printf ("LWFE: waitpid(-1, ...) returned %d, %s\n",
2591 ret
, errno
? safe_strerror (errno
) : "ERRNO-OK");
2597 debug_printf ("LLW: waitpid %ld received %s\n",
2598 (long) ret
, status_to_str (*wstatp
).c_str ());
2601 /* Filter all events. IOW, leave all events pending. We'll
2602 randomly select an event LWP out of all that have events
2604 filter_event (ret
, *wstatp
);
2605 /* Retry until nothing comes out of waitpid. A single
2606 SIGCHLD can indicate more than one child stopped. */
2610 /* Now that we've pulled all events out of the kernel, resume
2611 LWPs that don't have an interesting event to report. */
2612 if (stopping_threads
== NOT_STOPPING_THREADS
)
2613 for_each_thread ([this] (thread_info
*thread
)
2615 resume_stopped_resumed_lwps (thread
);
2618 /* ... and find an LWP with a status to report to the core, if
2620 event_thread
= find_thread_in_random ([&] (thread_info
*thread
)
2622 return status_pending_p_callback (thread
, filter_ptid
);
2625 if (event_thread
!= NULL
)
2627 event_child
= get_thread_lwp (event_thread
);
2628 *wstatp
= event_child
->status_pending
;
2629 event_child
->status_pending_p
= 0;
2630 event_child
->status_pending
= 0;
2634 /* Check for zombie thread group leaders. Those can't be reaped
2635 until all other threads in the thread group are. */
2636 check_zombie_leaders ();
2638 auto not_stopped
= [&] (thread_info
*thread
)
2640 return not_stopped_callback (thread
, wait_ptid
);
2643 /* If there are no resumed children left in the set of LWPs we
2644 want to wait for, bail. We can't just block in
2645 waitpid/sigsuspend, because lwps might have been left stopped
2646 in trace-stop state, and we'd be stuck forever waiting for
2647 their status to change (which would only happen if we resumed
2648 them). Even if WNOHANG is set, this return code is preferred
2649 over 0 (below), as it is more detailed. */
2650 if (find_thread (not_stopped
) == NULL
)
2653 debug_printf ("LLW: exit (no unwaited-for LWP)\n");
2654 gdb_sigmask (SIG_SETMASK
, &prev_mask
, NULL
);
2658 /* No interesting event to report to the caller. */
2659 if ((options
& WNOHANG
))
2662 debug_printf ("WNOHANG set, no event found\n");
2664 gdb_sigmask (SIG_SETMASK
, &prev_mask
, NULL
);
2668 /* Block until we get an event reported with SIGCHLD. */
2670 debug_printf ("sigsuspend'ing\n");
2672 sigsuspend (&prev_mask
);
2673 gdb_sigmask (SIG_SETMASK
, &prev_mask
, NULL
);
2677 gdb_sigmask (SIG_SETMASK
, &prev_mask
, NULL
);
2679 current_thread
= event_thread
;
2681 return lwpid_of (event_thread
);
2685 linux_process_target::wait_for_event (ptid_t ptid
, int *wstatp
, int options
)
2687 return wait_for_event_filtered (ptid
, ptid
, wstatp
, options
);
2690 /* Select one LWP out of those that have events pending. */
2693 select_event_lwp (struct lwp_info
**orig_lp
)
2695 struct thread_info
*event_thread
= NULL
;
2697 /* In all-stop, give preference to the LWP that is being
2698 single-stepped. There will be at most one, and it's the LWP that
2699 the core is most interested in. If we didn't do this, then we'd
2700 have to handle pending step SIGTRAPs somehow in case the core
2701 later continues the previously-stepped thread, otherwise we'd
2702 report the pending SIGTRAP, and the core, not having stepped the
2703 thread, wouldn't understand what the trap was for, and therefore
2704 would report it to the user as a random signal. */
2707 event_thread
= find_thread ([] (thread_info
*thread
)
2709 lwp_info
*lp
= get_thread_lwp (thread
);
2711 return (thread
->last_status
.kind () == TARGET_WAITKIND_IGNORE
2712 && thread
->last_resume_kind
== resume_step
2713 && lp
->status_pending_p
);
2716 if (event_thread
!= NULL
)
2719 debug_printf ("SEL: Select single-step %s\n",
2720 target_pid_to_str (ptid_of (event_thread
)).c_str ());
2723 if (event_thread
== NULL
)
2725 /* No single-stepping LWP. Select one at random, out of those
2726 which have had events. */
2728 event_thread
= find_thread_in_random ([&] (thread_info
*thread
)
2730 lwp_info
*lp
= get_thread_lwp (thread
);
2732 /* Only resumed LWPs that have an event pending. */
2733 return (thread
->last_status
.kind () == TARGET_WAITKIND_IGNORE
2734 && lp
->status_pending_p
);
2738 if (event_thread
!= NULL
)
2740 struct lwp_info
*event_lp
= get_thread_lwp (event_thread
);
2742 /* Switch the event LWP. */
2743 *orig_lp
= event_lp
;
2747 /* Decrement the suspend count of all LWPs, except EXCEPT, if non
2751 unsuspend_all_lwps (struct lwp_info
*except
)
2753 for_each_thread ([&] (thread_info
*thread
)
2755 lwp_info
*lwp
= get_thread_lwp (thread
);
2758 lwp_suspended_decr (lwp
);
2762 static bool lwp_running (thread_info
*thread
);
2764 /* Stabilize threads (move out of jump pads).
2766 If a thread is midway collecting a fast tracepoint, we need to
2767 finish the collection and move it out of the jump pad before
2768 reporting the signal.
2770 This avoids recursion while collecting (when a signal arrives
2771 midway, and the signal handler itself collects), which would trash
2772 the trace buffer. In case the user set a breakpoint in a signal
2773 handler, this avoids the backtrace showing the jump pad, etc..
2774 Most importantly, there are certain things we can't do safely if
2775 threads are stopped in a jump pad (or in its callee's). For
2778 - starting a new trace run. A thread still collecting the
2779 previous run, could trash the trace buffer when resumed. The trace
2780 buffer control structures would have been reset but the thread had
2781 no way to tell. The thread could even midway memcpy'ing to the
2782 buffer, which would mean that when resumed, it would clobber the
2783 trace buffer that had been set for a new run.
2785 - we can't rewrite/reuse the jump pads for new tracepoints
2786 safely. Say you do tstart while a thread is stopped midway while
2787 collecting. When the thread is later resumed, it finishes the
2788 collection, and returns to the jump pad, to execute the original
2789 instruction that was under the tracepoint jump at the time the
2790 older run had been started. If the jump pad had been rewritten
2791 since for something else in the new run, the thread would now
2792 execute the wrong / random instructions. */
2795 linux_process_target::stabilize_threads ()
2797 thread_info
*thread_stuck
= find_thread ([this] (thread_info
*thread
)
2799 return stuck_in_jump_pad (thread
);
2802 if (thread_stuck
!= NULL
)
2805 debug_printf ("can't stabilize, LWP %ld is stuck in jump pad\n",
2806 lwpid_of (thread_stuck
));
2810 thread_info
*saved_thread
= current_thread
;
2812 stabilizing_threads
= 1;
2815 for_each_thread ([this] (thread_info
*thread
)
2817 move_out_of_jump_pad (thread
);
2820 /* Loop until all are stopped out of the jump pads. */
2821 while (find_thread (lwp_running
) != NULL
)
2823 struct target_waitstatus ourstatus
;
2824 struct lwp_info
*lwp
;
2827 /* Note that we go through the full wait even loop. While
2828 moving threads out of jump pad, we need to be able to step
2829 over internal breakpoints and such. */
2830 wait_1 (minus_one_ptid
, &ourstatus
, 0);
2832 if (ourstatus
.kind () == TARGET_WAITKIND_STOPPED
)
2834 lwp
= get_thread_lwp (current_thread
);
2837 lwp_suspended_inc (lwp
);
2839 if (ourstatus
.sig () != GDB_SIGNAL_0
2840 || current_thread
->last_resume_kind
== resume_stop
)
2842 wstat
= W_STOPCODE (gdb_signal_to_host (ourstatus
.sig ()));
2843 enqueue_one_deferred_signal (lwp
, &wstat
);
2848 unsuspend_all_lwps (NULL
);
2850 stabilizing_threads
= 0;
2852 current_thread
= saved_thread
;
2856 thread_stuck
= find_thread ([this] (thread_info
*thread
)
2858 return stuck_in_jump_pad (thread
);
2861 if (thread_stuck
!= NULL
)
2862 debug_printf ("couldn't stabilize, LWP %ld got stuck in jump pad\n",
2863 lwpid_of (thread_stuck
));
2867 /* Convenience function that is called when the kernel reports an
2868 event that is not passed out to GDB. */
2871 ignore_event (struct target_waitstatus
*ourstatus
)
2873 /* If we got an event, there may still be others, as a single
2874 SIGCHLD can indicate more than one child stopped. This forces
2875 another target_wait call. */
2878 ourstatus
->set_ignore ();
2883 linux_process_target::filter_exit_event (lwp_info
*event_child
,
2884 target_waitstatus
*ourstatus
)
2886 client_state
&cs
= get_client_state ();
2887 struct thread_info
*thread
= get_lwp_thread (event_child
);
2888 ptid_t ptid
= ptid_of (thread
);
2890 if (!last_thread_of_process_p (pid_of (thread
)))
2892 if (cs
.report_thread_events
)
2893 ourstatus
->set_thread_exited (0);
2895 ourstatus
->set_ignore ();
2897 delete_lwp (event_child
);
2902 /* Returns 1 if GDB is interested in any event_child syscalls. */
2905 gdb_catching_syscalls_p (struct lwp_info
*event_child
)
2907 struct thread_info
*thread
= get_lwp_thread (event_child
);
2908 struct process_info
*proc
= get_thread_process (thread
);
2910 return !proc
->syscalls_to_catch
.empty ();
2914 linux_process_target::gdb_catch_this_syscall (lwp_info
*event_child
)
2917 struct thread_info
*thread
= get_lwp_thread (event_child
);
2918 struct process_info
*proc
= get_thread_process (thread
);
2920 if (proc
->syscalls_to_catch
.empty ())
2923 if (proc
->syscalls_to_catch
[0] == ANY_SYSCALL
)
2926 get_syscall_trapinfo (event_child
, &sysno
);
2928 for (int iter
: proc
->syscalls_to_catch
)
2936 linux_process_target::wait_1 (ptid_t ptid
, target_waitstatus
*ourstatus
,
2937 target_wait_flags target_options
)
2939 client_state
&cs
= get_client_state ();
2941 struct lwp_info
*event_child
;
2944 int step_over_finished
;
2945 int bp_explains_trap
;
2946 int maybe_internal_trap
;
2955 debug_printf ("wait_1: [%s]\n", target_pid_to_str (ptid
).c_str ());
2958 /* Translate generic target options into linux options. */
2960 if (target_options
& TARGET_WNOHANG
)
2963 bp_explains_trap
= 0;
2966 ourstatus
->set_ignore ();
2968 auto status_pending_p_any
= [&] (thread_info
*thread
)
2970 return status_pending_p_callback (thread
, minus_one_ptid
);
2973 auto not_stopped
= [&] (thread_info
*thread
)
2975 return not_stopped_callback (thread
, minus_one_ptid
);
2978 /* Find a resumed LWP, if any. */
2979 if (find_thread (status_pending_p_any
) != NULL
)
2981 else if (find_thread (not_stopped
) != NULL
)
2986 if (step_over_bkpt
== null_ptid
)
2987 pid
= wait_for_event (ptid
, &w
, options
);
2991 debug_printf ("step_over_bkpt set [%s], doing a blocking wait\n",
2992 target_pid_to_str (step_over_bkpt
).c_str ());
2993 pid
= wait_for_event (step_over_bkpt
, &w
, options
& ~WNOHANG
);
2996 if (pid
== 0 || (pid
== -1 && !any_resumed
))
2998 gdb_assert (target_options
& TARGET_WNOHANG
);
3002 debug_printf ("wait_1 ret = null_ptid, "
3003 "TARGET_WAITKIND_IGNORE\n");
3007 ourstatus
->set_ignore ();
3014 debug_printf ("wait_1 ret = null_ptid, "
3015 "TARGET_WAITKIND_NO_RESUMED\n");
3019 ourstatus
->set_no_resumed ();
3023 event_child
= get_thread_lwp (current_thread
);
3025 /* wait_for_event only returns an exit status for the last
3026 child of a process. Report it. */
3027 if (WIFEXITED (w
) || WIFSIGNALED (w
))
3031 ourstatus
->set_exited (WEXITSTATUS (w
));
3035 debug_printf ("wait_1 ret = %s, exited with "
3037 target_pid_to_str (ptid_of (current_thread
)).c_str (),
3044 ourstatus
->set_signalled (gdb_signal_from_host (WTERMSIG (w
)));
3048 debug_printf ("wait_1 ret = %s, terminated with "
3050 target_pid_to_str (ptid_of (current_thread
)).c_str (),
3056 if (ourstatus
->kind () == TARGET_WAITKIND_EXITED
)
3057 return filter_exit_event (event_child
, ourstatus
);
3059 return ptid_of (current_thread
);
3062 /* If step-over executes a breakpoint instruction, in the case of a
3063 hardware single step it means a gdb/gdbserver breakpoint had been
3064 planted on top of a permanent breakpoint, in the case of a software
3065 single step it may just mean that gdbserver hit the reinsert breakpoint.
3066 The PC has been adjusted by save_stop_reason to point at
3067 the breakpoint address.
3068 So in the case of the hardware single step advance the PC manually
3069 past the breakpoint and in the case of software single step advance only
3070 if it's not the single_step_breakpoint we are hitting.
3071 This avoids that a program would keep trapping a permanent breakpoint
3073 if (step_over_bkpt
!= null_ptid
3074 && event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3075 && (event_child
->stepping
3076 || !single_step_breakpoint_inserted_here (event_child
->stop_pc
)))
3078 int increment_pc
= 0;
3079 int breakpoint_kind
= 0;
3080 CORE_ADDR stop_pc
= event_child
->stop_pc
;
3082 breakpoint_kind
= breakpoint_kind_from_current_state (&stop_pc
);
3083 sw_breakpoint_from_kind (breakpoint_kind
, &increment_pc
);
3087 debug_printf ("step-over for %s executed software breakpoint\n",
3088 target_pid_to_str (ptid_of (current_thread
)).c_str ());
3091 if (increment_pc
!= 0)
3093 struct regcache
*regcache
3094 = get_thread_regcache (current_thread
, 1);
3096 event_child
->stop_pc
+= increment_pc
;
3097 low_set_pc (regcache
, event_child
->stop_pc
);
3099 if (!low_breakpoint_at (event_child
->stop_pc
))
3100 event_child
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3104 /* If this event was not handled before, and is not a SIGTRAP, we
3105 report it. SIGILL and SIGSEGV are also treated as traps in case
3106 a breakpoint is inserted at the current PC. If this target does
3107 not support internal breakpoints at all, we also report the
3108 SIGTRAP without further processing; it's of no concern to us. */
3110 = (low_supports_breakpoints ()
3111 && (WSTOPSIG (w
) == SIGTRAP
3112 || ((WSTOPSIG (w
) == SIGILL
3113 || WSTOPSIG (w
) == SIGSEGV
)
3114 && low_breakpoint_at (event_child
->stop_pc
))));
3116 if (maybe_internal_trap
)
3118 /* Handle anything that requires bookkeeping before deciding to
3119 report the event or continue waiting. */
3121 /* First check if we can explain the SIGTRAP with an internal
3122 breakpoint, or if we should possibly report the event to GDB.
3123 Do this before anything that may remove or insert a
3125 bp_explains_trap
= breakpoint_inserted_here (event_child
->stop_pc
);
3127 /* We have a SIGTRAP, possibly a step-over dance has just
3128 finished. If so, tweak the state machine accordingly,
3129 reinsert breakpoints and delete any single-step
3131 step_over_finished
= finish_step_over (event_child
);
3133 /* Now invoke the callbacks of any internal breakpoints there. */
3134 check_breakpoints (event_child
->stop_pc
);
3136 /* Handle tracepoint data collecting. This may overflow the
3137 trace buffer, and cause a tracing stop, removing
3139 trace_event
= handle_tracepoints (event_child
);
3141 if (bp_explains_trap
)
3144 debug_printf ("Hit a gdbserver breakpoint.\n");
3149 /* We have some other signal, possibly a step-over dance was in
3150 progress, and it should be cancelled too. */
3151 step_over_finished
= finish_step_over (event_child
);
3154 /* We have all the data we need. Either report the event to GDB, or
3155 resume threads and keep waiting for more. */
3157 /* If we're collecting a fast tracepoint, finish the collection and
3158 move out of the jump pad before delivering a signal. See
3159 linux_stabilize_threads. */
3162 && WSTOPSIG (w
) != SIGTRAP
3163 && supports_fast_tracepoints ()
3164 && agent_loaded_p ())
3167 debug_printf ("Got signal %d for LWP %ld. Check if we need "
3168 "to defer or adjust it.\n",
3169 WSTOPSIG (w
), lwpid_of (current_thread
));
3171 /* Allow debugging the jump pad itself. */
3172 if (current_thread
->last_resume_kind
!= resume_step
3173 && maybe_move_out_of_jump_pad (event_child
, &w
))
3175 enqueue_one_deferred_signal (event_child
, &w
);
3178 debug_printf ("Signal %d for LWP %ld deferred (in jump pad)\n",
3179 WSTOPSIG (w
), lwpid_of (current_thread
));
3181 resume_one_lwp (event_child
, 0, 0, NULL
);
3185 return ignore_event (ourstatus
);
3189 if (event_child
->collecting_fast_tracepoint
3190 != fast_tpoint_collect_result::not_collecting
)
3193 debug_printf ("LWP %ld was trying to move out of the jump pad (%d). "
3194 "Check if we're already there.\n",
3195 lwpid_of (current_thread
),
3196 (int) event_child
->collecting_fast_tracepoint
);
3200 event_child
->collecting_fast_tracepoint
3201 = linux_fast_tracepoint_collecting (event_child
, NULL
);
3203 if (event_child
->collecting_fast_tracepoint
3204 != fast_tpoint_collect_result::before_insn
)
3206 /* No longer need this breakpoint. */
3207 if (event_child
->exit_jump_pad_bkpt
!= NULL
)
3210 debug_printf ("No longer need exit-jump-pad bkpt; removing it."
3211 "stopping all threads momentarily.\n");
3213 /* Other running threads could hit this breakpoint.
3214 We don't handle moribund locations like GDB does,
3215 instead we always pause all threads when removing
3216 breakpoints, so that any step-over or
3217 decr_pc_after_break adjustment is always taken
3218 care of while the breakpoint is still
3220 stop_all_lwps (1, event_child
);
3222 delete_breakpoint (event_child
->exit_jump_pad_bkpt
);
3223 event_child
->exit_jump_pad_bkpt
= NULL
;
3225 unstop_all_lwps (1, event_child
);
3227 gdb_assert (event_child
->suspended
>= 0);
3231 if (event_child
->collecting_fast_tracepoint
3232 == fast_tpoint_collect_result::not_collecting
)
3235 debug_printf ("fast tracepoint finished "
3236 "collecting successfully.\n");
3238 /* We may have a deferred signal to report. */
3239 if (dequeue_one_deferred_signal (event_child
, &w
))
3242 debug_printf ("dequeued one signal.\n");
3247 debug_printf ("no deferred signals.\n");
3249 if (stabilizing_threads
)
3251 ourstatus
->set_stopped (GDB_SIGNAL_0
);
3255 debug_printf ("wait_1 ret = %s, stopped "
3256 "while stabilizing threads\n",
3258 (ptid_of (current_thread
)).c_str ());
3262 return ptid_of (current_thread
);
3268 /* Check whether GDB would be interested in this event. */
3270 /* Check if GDB is interested in this syscall. */
3272 && WSTOPSIG (w
) == SYSCALL_SIGTRAP
3273 && !gdb_catch_this_syscall (event_child
))
3277 debug_printf ("Ignored syscall for LWP %ld.\n",
3278 lwpid_of (current_thread
));
3281 resume_one_lwp (event_child
, event_child
->stepping
, 0, NULL
);
3285 return ignore_event (ourstatus
);
3288 /* If GDB is not interested in this signal, don't stop other
3289 threads, and don't report it to GDB. Just resume the inferior
3290 right away. We do this for threading-related signals as well as
3291 any that GDB specifically requested we ignore. But never ignore
3292 SIGSTOP if we sent it ourselves, and do not ignore signals when
3293 stepping - they may require special handling to skip the signal
3294 handler. Also never ignore signals that could be caused by a
3297 && current_thread
->last_resume_kind
!= resume_step
3299 #if defined (USE_THREAD_DB) && !defined (__ANDROID__)
3300 (current_process ()->priv
->thread_db
!= NULL
3301 && (WSTOPSIG (w
) == __SIGRTMIN
3302 || WSTOPSIG (w
) == __SIGRTMIN
+ 1))
3305 (cs
.pass_signals
[gdb_signal_from_host (WSTOPSIG (w
))]
3306 && !(WSTOPSIG (w
) == SIGSTOP
3307 && current_thread
->last_resume_kind
== resume_stop
)
3308 && !linux_wstatus_maybe_breakpoint (w
))))
3310 siginfo_t info
, *info_p
;
3313 debug_printf ("Ignored signal %d for LWP %ld.\n",
3314 WSTOPSIG (w
), lwpid_of (current_thread
));
3316 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
3317 (PTRACE_TYPE_ARG3
) 0, &info
) == 0)
3322 if (step_over_finished
)
3324 /* We cancelled this thread's step-over above. We still
3325 need to unsuspend all other LWPs, and set them back
3326 running again while the signal handler runs. */
3327 unsuspend_all_lwps (event_child
);
3329 /* Enqueue the pending signal info so that proceed_all_lwps
3331 enqueue_pending_signal (event_child
, WSTOPSIG (w
), info_p
);
3333 proceed_all_lwps ();
3337 resume_one_lwp (event_child
, event_child
->stepping
,
3338 WSTOPSIG (w
), info_p
);
3344 return ignore_event (ourstatus
);
3347 /* Note that all addresses are always "out of the step range" when
3348 there's no range to begin with. */
3349 in_step_range
= lwp_in_step_range (event_child
);
3351 /* If GDB wanted this thread to single step, and the thread is out
3352 of the step range, we always want to report the SIGTRAP, and let
3353 GDB handle it. Watchpoints should always be reported. So should
3354 signals we can't explain. A SIGTRAP we can't explain could be a
3355 GDB breakpoint --- we may or not support Z0 breakpoints. If we
3356 do, we're be able to handle GDB breakpoints on top of internal
3357 breakpoints, by handling the internal breakpoint and still
3358 reporting the event to GDB. If we don't, we're out of luck, GDB
3359 won't see the breakpoint hit. If we see a single-step event but
3360 the thread should be continuing, don't pass the trap to gdb.
3361 That indicates that we had previously finished a single-step but
3362 left the single-step pending -- see
3363 complete_ongoing_step_over. */
3364 report_to_gdb
= (!maybe_internal_trap
3365 || (current_thread
->last_resume_kind
== resume_step
3367 || event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
3369 && !bp_explains_trap
3371 && !step_over_finished
3372 && !(current_thread
->last_resume_kind
== resume_continue
3373 && event_child
->stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
))
3374 || (gdb_breakpoint_here (event_child
->stop_pc
)
3375 && gdb_condition_true_at_breakpoint (event_child
->stop_pc
)
3376 && gdb_no_commands_at_breakpoint (event_child
->stop_pc
))
3377 || event_child
->waitstatus
.kind () != TARGET_WAITKIND_IGNORE
);
3379 run_breakpoint_commands (event_child
->stop_pc
);
3381 /* We found no reason GDB would want us to stop. We either hit one
3382 of our own breakpoints, or finished an internal step GDB
3383 shouldn't know about. */
3388 if (bp_explains_trap
)
3389 debug_printf ("Hit a gdbserver breakpoint.\n");
3390 if (step_over_finished
)
3391 debug_printf ("Step-over finished.\n");
3393 debug_printf ("Tracepoint event.\n");
3394 if (lwp_in_step_range (event_child
))
3395 debug_printf ("Range stepping pc 0x%s [0x%s, 0x%s).\n",
3396 paddress (event_child
->stop_pc
),
3397 paddress (event_child
->step_range_start
),
3398 paddress (event_child
->step_range_end
));
3401 /* We're not reporting this breakpoint to GDB, so apply the
3402 decr_pc_after_break adjustment to the inferior's regcache
3405 if (low_supports_breakpoints ())
3407 struct regcache
*regcache
3408 = get_thread_regcache (current_thread
, 1);
3409 low_set_pc (regcache
, event_child
->stop_pc
);
3412 if (step_over_finished
)
3414 /* If we have finished stepping over a breakpoint, we've
3415 stopped and suspended all LWPs momentarily except the
3416 stepping one. This is where we resume them all again.
3417 We're going to keep waiting, so use proceed, which
3418 handles stepping over the next breakpoint. */
3419 unsuspend_all_lwps (event_child
);
3423 /* Remove the single-step breakpoints if any. Note that
3424 there isn't single-step breakpoint if we finished stepping
3426 if (supports_software_single_step ()
3427 && has_single_step_breakpoints (current_thread
))
3429 stop_all_lwps (0, event_child
);
3430 delete_single_step_breakpoints (current_thread
);
3431 unstop_all_lwps (0, event_child
);
3436 debug_printf ("proceeding all threads.\n");
3437 proceed_all_lwps ();
3442 return ignore_event (ourstatus
);
3447 if (event_child
->waitstatus
.kind () != TARGET_WAITKIND_IGNORE
)
3448 debug_printf ("LWP %ld: extended event with waitstatus %s\n",
3449 lwpid_of (get_lwp_thread (event_child
)),
3450 event_child
->waitstatus
.to_string ().c_str ());
3451 if (current_thread
->last_resume_kind
== resume_step
)
3453 if (event_child
->step_range_start
== event_child
->step_range_end
)
3454 debug_printf ("GDB wanted to single-step, reporting event.\n");
3455 else if (!lwp_in_step_range (event_child
))
3456 debug_printf ("Out of step range, reporting event.\n");
3458 if (event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
)
3459 debug_printf ("Stopped by watchpoint.\n");
3460 else if (gdb_breakpoint_here (event_child
->stop_pc
))
3461 debug_printf ("Stopped by GDB breakpoint.\n");
3463 debug_printf ("Hit a non-gdbserver trap event.\n");
3466 /* Alright, we're going to report a stop. */
3468 /* Remove single-step breakpoints. */
3469 if (supports_software_single_step ())
3471 /* Remove single-step breakpoints or not. It it is true, stop all
3472 lwps, so that other threads won't hit the breakpoint in the
3474 int remove_single_step_breakpoints_p
= 0;
3478 remove_single_step_breakpoints_p
3479 = has_single_step_breakpoints (current_thread
);
3483 /* In all-stop, a stop reply cancels all previous resume
3484 requests. Delete all single-step breakpoints. */
3486 find_thread ([&] (thread_info
*thread
) {
3487 if (has_single_step_breakpoints (thread
))
3489 remove_single_step_breakpoints_p
= 1;
3497 if (remove_single_step_breakpoints_p
)
3499 /* If we remove single-step breakpoints from memory, stop all lwps,
3500 so that other threads won't hit the breakpoint in the staled
3502 stop_all_lwps (0, event_child
);
3506 gdb_assert (has_single_step_breakpoints (current_thread
));
3507 delete_single_step_breakpoints (current_thread
);
3511 for_each_thread ([] (thread_info
*thread
){
3512 if (has_single_step_breakpoints (thread
))
3513 delete_single_step_breakpoints (thread
);
3517 unstop_all_lwps (0, event_child
);
3521 if (!stabilizing_threads
)
3523 /* In all-stop, stop all threads. */
3525 stop_all_lwps (0, NULL
);
3527 if (step_over_finished
)
3531 /* If we were doing a step-over, all other threads but
3532 the stepping one had been paused in start_step_over,
3533 with their suspend counts incremented. We don't want
3534 to do a full unstop/unpause, because we're in
3535 all-stop mode (so we want threads stopped), but we
3536 still need to unsuspend the other threads, to
3537 decrement their `suspended' count back. */
3538 unsuspend_all_lwps (event_child
);
3542 /* If we just finished a step-over, then all threads had
3543 been momentarily paused. In all-stop, that's fine,
3544 we want threads stopped by now anyway. In non-stop,
3545 we need to re-resume threads that GDB wanted to be
3547 unstop_all_lwps (1, event_child
);
3551 /* If we're not waiting for a specific LWP, choose an event LWP
3552 from among those that have had events. Giving equal priority
3553 to all LWPs that have had events helps prevent
3555 if (ptid
== minus_one_ptid
)
3557 event_child
->status_pending_p
= 1;
3558 event_child
->status_pending
= w
;
3560 select_event_lwp (&event_child
);
3562 /* current_thread and event_child must stay in sync. */
3563 current_thread
= get_lwp_thread (event_child
);
3565 event_child
->status_pending_p
= 0;
3566 w
= event_child
->status_pending
;
3570 /* Stabilize threads (move out of jump pads). */
3572 target_stabilize_threads ();
3576 /* If we just finished a step-over, then all threads had been
3577 momentarily paused. In all-stop, that's fine, we want
3578 threads stopped by now anyway. In non-stop, we need to
3579 re-resume threads that GDB wanted to be running. */
3580 if (step_over_finished
)
3581 unstop_all_lwps (1, event_child
);
3584 if (event_child
->waitstatus
.kind () != TARGET_WAITKIND_IGNORE
)
3586 /* If the reported event is an exit, fork, vfork or exec, let
3589 /* Break the unreported fork relationship chain. */
3590 if (event_child
->waitstatus
.kind () == TARGET_WAITKIND_FORKED
3591 || event_child
->waitstatus
.kind () == TARGET_WAITKIND_VFORKED
)
3593 event_child
->fork_relative
->fork_relative
= NULL
;
3594 event_child
->fork_relative
= NULL
;
3597 *ourstatus
= event_child
->waitstatus
;
3598 /* Clear the event lwp's waitstatus since we handled it already. */
3599 event_child
->waitstatus
.set_ignore ();
3603 /* The actual stop signal is overwritten below. */
3604 ourstatus
->set_stopped (GDB_SIGNAL_0
);
3607 /* Now that we've selected our final event LWP, un-adjust its PC if
3608 it was a software breakpoint, and the client doesn't know we can
3609 adjust the breakpoint ourselves. */
3610 if (event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3611 && !cs
.swbreak_feature
)
3613 int decr_pc
= low_decr_pc_after_break ();
3617 struct regcache
*regcache
3618 = get_thread_regcache (current_thread
, 1);
3619 low_set_pc (regcache
, event_child
->stop_pc
+ decr_pc
);
3623 if (WSTOPSIG (w
) == SYSCALL_SIGTRAP
)
3627 get_syscall_trapinfo (event_child
, &syscall_number
);
3628 if (event_child
->syscall_state
== TARGET_WAITKIND_SYSCALL_ENTRY
)
3629 ourstatus
->set_syscall_entry (syscall_number
);
3630 else if (event_child
->syscall_state
== TARGET_WAITKIND_SYSCALL_RETURN
)
3631 ourstatus
->set_syscall_return (syscall_number
);
3633 gdb_assert_not_reached ("unexpected syscall state");
3635 else if (current_thread
->last_resume_kind
== resume_stop
3636 && WSTOPSIG (w
) == SIGSTOP
)
3638 /* A thread that has been requested to stop by GDB with vCont;t,
3639 and it stopped cleanly, so report as SIG0. The use of
3640 SIGSTOP is an implementation detail. */
3641 ourstatus
->set_stopped (GDB_SIGNAL_0
);
3643 else if (current_thread
->last_resume_kind
== resume_stop
3644 && WSTOPSIG (w
) != SIGSTOP
)
3646 /* A thread that has been requested to stop by GDB with vCont;t,
3647 but, it stopped for other reasons. */
3648 ourstatus
->set_stopped (gdb_signal_from_host (WSTOPSIG (w
)));
3650 else if (ourstatus
->kind () == TARGET_WAITKIND_STOPPED
)
3651 ourstatus
->set_stopped (gdb_signal_from_host (WSTOPSIG (w
)));
3653 gdb_assert (step_over_bkpt
== null_ptid
);
3657 debug_printf ("wait_1 ret = %s, %d, %d\n",
3658 target_pid_to_str (ptid_of (current_thread
)).c_str (),
3659 ourstatus
->kind (), ourstatus
->sig ());
3663 if (ourstatus
->kind () == TARGET_WAITKIND_EXITED
)
3664 return filter_exit_event (event_child
, ourstatus
);
3666 return ptid_of (current_thread
);
3669 /* Get rid of any pending event in the pipe. */
3671 async_file_flush (void)
3677 ret
= read (linux_event_pipe
[0], &buf
, 1);
3678 while (ret
>= 0 || (ret
== -1 && errno
== EINTR
));
3681 /* Put something in the pipe, so the event loop wakes up. */
3683 async_file_mark (void)
3687 async_file_flush ();
3690 ret
= write (linux_event_pipe
[1], "+", 1);
3691 while (ret
== 0 || (ret
== -1 && errno
== EINTR
));
3693 /* Ignore EAGAIN. If the pipe is full, the event loop will already
3694 be awakened anyway. */
3698 linux_process_target::wait (ptid_t ptid
,
3699 target_waitstatus
*ourstatus
,
3700 target_wait_flags target_options
)
3704 /* Flush the async file first. */
3705 if (target_is_async_p ())
3706 async_file_flush ();
3710 event_ptid
= wait_1 (ptid
, ourstatus
, target_options
);
3712 while ((target_options
& TARGET_WNOHANG
) == 0
3713 && event_ptid
== null_ptid
3714 && ourstatus
->kind () == TARGET_WAITKIND_IGNORE
);
3716 /* If at least one stop was reported, there may be more. A single
3717 SIGCHLD can signal more than one child stop. */
3718 if (target_is_async_p ()
3719 && (target_options
& TARGET_WNOHANG
) != 0
3720 && event_ptid
!= null_ptid
)
3726 /* Send a signal to an LWP. */
3729 kill_lwp (unsigned long lwpid
, int signo
)
3734 ret
= syscall (__NR_tkill
, lwpid
, signo
);
3735 if (errno
== ENOSYS
)
3737 /* If tkill fails, then we are not using nptl threads, a
3738 configuration we no longer support. */
3739 perror_with_name (("tkill"));
3745 linux_stop_lwp (struct lwp_info
*lwp
)
3751 send_sigstop (struct lwp_info
*lwp
)
3755 pid
= lwpid_of (get_lwp_thread (lwp
));
3757 /* If we already have a pending stop signal for this process, don't
3759 if (lwp
->stop_expected
)
3762 debug_printf ("Have pending sigstop for lwp %d\n", pid
);
3768 debug_printf ("Sending sigstop to lwp %d\n", pid
);
3770 lwp
->stop_expected
= 1;
3771 kill_lwp (pid
, SIGSTOP
);
3775 send_sigstop (thread_info
*thread
, lwp_info
*except
)
3777 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3779 /* Ignore EXCEPT. */
3789 /* Increment the suspend count of an LWP, and stop it, if not stopped
3792 suspend_and_send_sigstop (thread_info
*thread
, lwp_info
*except
)
3794 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3796 /* Ignore EXCEPT. */
3800 lwp_suspended_inc (lwp
);
3802 send_sigstop (thread
, except
);
3806 mark_lwp_dead (struct lwp_info
*lwp
, int wstat
)
3808 /* Store the exit status for later. */
3809 lwp
->status_pending_p
= 1;
3810 lwp
->status_pending
= wstat
;
3812 /* Store in waitstatus as well, as there's nothing else to process
3814 if (WIFEXITED (wstat
))
3815 lwp
->waitstatus
.set_exited (WEXITSTATUS (wstat
));
3816 else if (WIFSIGNALED (wstat
))
3817 lwp
->waitstatus
.set_signalled (gdb_signal_from_host (WTERMSIG (wstat
)));
3819 /* Prevent trying to stop it. */
3822 /* No further stops are expected from a dead lwp. */
3823 lwp
->stop_expected
= 0;
3826 /* Return true if LWP has exited already, and has a pending exit event
3827 to report to GDB. */
3830 lwp_is_marked_dead (struct lwp_info
*lwp
)
3832 return (lwp
->status_pending_p
3833 && (WIFEXITED (lwp
->status_pending
)
3834 || WIFSIGNALED (lwp
->status_pending
)));
3838 linux_process_target::wait_for_sigstop ()
3840 struct thread_info
*saved_thread
;
3845 saved_thread
= current_thread
;
3846 if (saved_thread
!= NULL
)
3847 saved_tid
= saved_thread
->id
;
3849 saved_tid
= null_ptid
; /* avoid bogus unused warning */
3852 debug_printf ("wait_for_sigstop: pulling events\n");
3854 /* Passing NULL_PTID as filter indicates we want all events to be
3855 left pending. Eventually this returns when there are no
3856 unwaited-for children left. */
3857 ret
= wait_for_event_filtered (minus_one_ptid
, null_ptid
, &wstat
, __WALL
);
3858 gdb_assert (ret
== -1);
3860 if (saved_thread
== NULL
|| mythread_alive (saved_tid
))
3861 current_thread
= saved_thread
;
3865 debug_printf ("Previously current thread died.\n");
3867 /* We can't change the current inferior behind GDB's back,
3868 otherwise, a subsequent command may apply to the wrong
3870 current_thread
= NULL
;
3875 linux_process_target::stuck_in_jump_pad (thread_info
*thread
)
3877 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3879 if (lwp
->suspended
!= 0)
3881 internal_error (__FILE__
, __LINE__
,
3882 "LWP %ld is suspended, suspended=%d\n",
3883 lwpid_of (thread
), lwp
->suspended
);
3885 gdb_assert (lwp
->stopped
);
3887 /* Allow debugging the jump pad, gdb_collect, etc.. */
3888 return (supports_fast_tracepoints ()
3889 && agent_loaded_p ()
3890 && (gdb_breakpoint_here (lwp
->stop_pc
)
3891 || lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
3892 || thread
->last_resume_kind
== resume_step
)
3893 && (linux_fast_tracepoint_collecting (lwp
, NULL
)
3894 != fast_tpoint_collect_result::not_collecting
));
3898 linux_process_target::move_out_of_jump_pad (thread_info
*thread
)
3900 struct thread_info
*saved_thread
;
3901 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3904 if (lwp
->suspended
!= 0)
3906 internal_error (__FILE__
, __LINE__
,
3907 "LWP %ld is suspended, suspended=%d\n",
3908 lwpid_of (thread
), lwp
->suspended
);
3910 gdb_assert (lwp
->stopped
);
3912 /* For gdb_breakpoint_here. */
3913 saved_thread
= current_thread
;
3914 current_thread
= thread
;
3916 wstat
= lwp
->status_pending_p
? &lwp
->status_pending
: NULL
;
3918 /* Allow debugging the jump pad, gdb_collect, etc. */
3919 if (!gdb_breakpoint_here (lwp
->stop_pc
)
3920 && lwp
->stop_reason
!= TARGET_STOPPED_BY_WATCHPOINT
3921 && thread
->last_resume_kind
!= resume_step
3922 && maybe_move_out_of_jump_pad (lwp
, wstat
))
3925 debug_printf ("LWP %ld needs stabilizing (in jump pad)\n",
3930 lwp
->status_pending_p
= 0;
3931 enqueue_one_deferred_signal (lwp
, wstat
);
3934 debug_printf ("Signal %d for LWP %ld deferred "
3936 WSTOPSIG (*wstat
), lwpid_of (thread
));
3939 resume_one_lwp (lwp
, 0, 0, NULL
);
3942 lwp_suspended_inc (lwp
);
3944 current_thread
= saved_thread
;
3948 lwp_running (thread_info
*thread
)
3950 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3952 if (lwp_is_marked_dead (lwp
))
3955 return !lwp
->stopped
;
3959 linux_process_target::stop_all_lwps (int suspend
, lwp_info
*except
)
3961 /* Should not be called recursively. */
3962 gdb_assert (stopping_threads
== NOT_STOPPING_THREADS
);
3967 debug_printf ("stop_all_lwps (%s, except=%s)\n",
3968 suspend
? "stop-and-suspend" : "stop",
3971 (ptid_of (get_lwp_thread (except
))).c_str ()
3975 stopping_threads
= (suspend
3976 ? STOPPING_AND_SUSPENDING_THREADS
3977 : STOPPING_THREADS
);
3980 for_each_thread ([&] (thread_info
*thread
)
3982 suspend_and_send_sigstop (thread
, except
);
3985 for_each_thread ([&] (thread_info
*thread
)
3987 send_sigstop (thread
, except
);
3990 wait_for_sigstop ();
3991 stopping_threads
= NOT_STOPPING_THREADS
;
3995 debug_printf ("stop_all_lwps done, setting stopping_threads "
3996 "back to !stopping\n");
4001 /* Enqueue one signal in the chain of signals which need to be
4002 delivered to this process on next resume. */
4005 enqueue_pending_signal (struct lwp_info
*lwp
, int signal
, siginfo_t
*info
)
4007 lwp
->pending_signals
.emplace_back (signal
);
4008 if (info
== nullptr)
4009 memset (&lwp
->pending_signals
.back ().info
, 0, sizeof (siginfo_t
));
4011 lwp
->pending_signals
.back ().info
= *info
;
4015 linux_process_target::install_software_single_step_breakpoints (lwp_info
*lwp
)
4017 struct thread_info
*thread
= get_lwp_thread (lwp
);
4018 struct regcache
*regcache
= get_thread_regcache (thread
, 1);
4020 scoped_restore save_current_thread
= make_scoped_restore (¤t_thread
);
4022 current_thread
= thread
;
4023 std::vector
<CORE_ADDR
> next_pcs
= low_get_next_pcs (regcache
);
4025 for (CORE_ADDR pc
: next_pcs
)
4026 set_single_step_breakpoint (pc
, current_ptid
);
4030 linux_process_target::single_step (lwp_info
* lwp
)
4034 if (supports_hardware_single_step ())
4038 else if (supports_software_single_step ())
4040 install_software_single_step_breakpoints (lwp
);
4046 debug_printf ("stepping is not implemented on this target");
4052 /* The signal can be delivered to the inferior if we are not trying to
4053 finish a fast tracepoint collect. Since signal can be delivered in
4054 the step-over, the program may go to signal handler and trap again
4055 after return from the signal handler. We can live with the spurious
4059 lwp_signal_can_be_delivered (struct lwp_info
*lwp
)
4061 return (lwp
->collecting_fast_tracepoint
4062 == fast_tpoint_collect_result::not_collecting
);
4066 linux_process_target::resume_one_lwp_throw (lwp_info
*lwp
, int step
,
4067 int signal
, siginfo_t
*info
)
4069 struct thread_info
*thread
= get_lwp_thread (lwp
);
4070 struct thread_info
*saved_thread
;
4072 struct process_info
*proc
= get_thread_process (thread
);
4074 /* Note that target description may not be initialised
4075 (proc->tdesc == NULL) at this point because the program hasn't
4076 stopped at the first instruction yet. It means GDBserver skips
4077 the extra traps from the wrapper program (see option --wrapper).
4078 Code in this function that requires register access should be
4079 guarded by proc->tdesc == NULL or something else. */
4081 if (lwp
->stopped
== 0)
4084 gdb_assert (lwp
->waitstatus
.kind () == TARGET_WAITKIND_IGNORE
);
4086 fast_tpoint_collect_result fast_tp_collecting
4087 = lwp
->collecting_fast_tracepoint
;
4089 gdb_assert (!stabilizing_threads
4090 || (fast_tp_collecting
4091 != fast_tpoint_collect_result::not_collecting
));
4093 /* Cancel actions that rely on GDB not changing the PC (e.g., the
4094 user used the "jump" command, or "set $pc = foo"). */
4095 if (thread
->while_stepping
!= NULL
&& lwp
->stop_pc
!= get_pc (lwp
))
4097 /* Collecting 'while-stepping' actions doesn't make sense
4099 release_while_stepping_state_list (thread
);
4102 /* If we have pending signals or status, and a new signal, enqueue the
4103 signal. Also enqueue the signal if it can't be delivered to the
4104 inferior right now. */
4106 && (lwp
->status_pending_p
4107 || !lwp
->pending_signals
.empty ()
4108 || !lwp_signal_can_be_delivered (lwp
)))
4110 enqueue_pending_signal (lwp
, signal
, info
);
4112 /* Postpone any pending signal. It was enqueued above. */
4116 if (lwp
->status_pending_p
)
4119 debug_printf ("Not resuming lwp %ld (%s, stop %s);"
4120 " has pending status\n",
4121 lwpid_of (thread
), step
? "step" : "continue",
4122 lwp
->stop_expected
? "expected" : "not expected");
4126 saved_thread
= current_thread
;
4127 current_thread
= thread
;
4129 /* This bit needs some thinking about. If we get a signal that
4130 we must report while a single-step reinsert is still pending,
4131 we often end up resuming the thread. It might be better to
4132 (ew) allow a stack of pending events; then we could be sure that
4133 the reinsert happened right away and not lose any signals.
4135 Making this stack would also shrink the window in which breakpoints are
4136 uninserted (see comment in linux_wait_for_lwp) but not enough for
4137 complete correctness, so it won't solve that problem. It may be
4138 worthwhile just to solve this one, however. */
4139 if (lwp
->bp_reinsert
!= 0)
4142 debug_printf (" pending reinsert at 0x%s\n",
4143 paddress (lwp
->bp_reinsert
));
4145 if (supports_hardware_single_step ())
4147 if (fast_tp_collecting
== fast_tpoint_collect_result::not_collecting
)
4150 warning ("BAD - reinserting but not stepping.");
4152 warning ("BAD - reinserting and suspended(%d).",
4157 step
= maybe_hw_step (thread
);
4160 if (fast_tp_collecting
== fast_tpoint_collect_result::before_insn
)
4163 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
4164 " (exit-jump-pad-bkpt)\n",
4167 else if (fast_tp_collecting
== fast_tpoint_collect_result::at_insn
)
4170 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
4171 " single-stepping\n",
4174 if (supports_hardware_single_step ())
4178 internal_error (__FILE__
, __LINE__
,
4179 "moving out of jump pad single-stepping"
4180 " not implemented on this target");
4184 /* If we have while-stepping actions in this thread set it stepping.
4185 If we have a signal to deliver, it may or may not be set to
4186 SIG_IGN, we don't know. Assume so, and allow collecting
4187 while-stepping into a signal handler. A possible smart thing to
4188 do would be to set an internal breakpoint at the signal return
4189 address, continue, and carry on catching this while-stepping
4190 action only when that breakpoint is hit. A future
4192 if (thread
->while_stepping
!= NULL
)
4195 debug_printf ("lwp %ld has a while-stepping action -> forcing step.\n",
4198 step
= single_step (lwp
);
4201 if (proc
->tdesc
!= NULL
&& low_supports_breakpoints ())
4203 struct regcache
*regcache
= get_thread_regcache (current_thread
, 1);
4205 lwp
->stop_pc
= low_get_pc (regcache
);
4209 debug_printf (" %s from pc 0x%lx\n", step
? "step" : "continue",
4210 (long) lwp
->stop_pc
);
4214 /* If we have pending signals, consume one if it can be delivered to
4216 if (!lwp
->pending_signals
.empty () && lwp_signal_can_be_delivered (lwp
))
4218 const pending_signal
&p_sig
= lwp
->pending_signals
.front ();
4220 signal
= p_sig
.signal
;
4221 if (p_sig
.info
.si_signo
!= 0)
4222 ptrace (PTRACE_SETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
4225 lwp
->pending_signals
.pop_front ();
4229 debug_printf ("Resuming lwp %ld (%s, signal %d, stop %s)\n",
4230 lwpid_of (thread
), step
? "step" : "continue", signal
,
4231 lwp
->stop_expected
? "expected" : "not expected");
4233 low_prepare_to_resume (lwp
);
4235 regcache_invalidate_thread (thread
);
4237 lwp
->stepping
= step
;
4239 ptrace_request
= PTRACE_SINGLESTEP
;
4240 else if (gdb_catching_syscalls_p (lwp
))
4241 ptrace_request
= PTRACE_SYSCALL
;
4243 ptrace_request
= PTRACE_CONT
;
4244 ptrace (ptrace_request
,
4246 (PTRACE_TYPE_ARG3
) 0,
4247 /* Coerce to a uintptr_t first to avoid potential gcc warning
4248 of coercing an 8 byte integer to a 4 byte pointer. */
4249 (PTRACE_TYPE_ARG4
) (uintptr_t) signal
);
4251 current_thread
= saved_thread
;
4253 perror_with_name ("resuming thread");
4255 /* Successfully resumed. Clear state that no longer makes sense,
4256 and mark the LWP as running. Must not do this before resuming
4257 otherwise if that fails other code will be confused. E.g., we'd
4258 later try to stop the LWP and hang forever waiting for a stop
4259 status. Note that we must not throw after this is cleared,
4260 otherwise handle_zombie_lwp_error would get confused. */
4262 lwp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
4266 linux_process_target::low_prepare_to_resume (lwp_info
*lwp
)
4271 /* Called when we try to resume a stopped LWP and that errors out. If
4272 the LWP is no longer in ptrace-stopped state (meaning it's zombie,
4273 or about to become), discard the error, clear any pending status
4274 the LWP may have, and return true (we'll collect the exit status
4275 soon enough). Otherwise, return false. */
4278 check_ptrace_stopped_lwp_gone (struct lwp_info
*lp
)
4280 struct thread_info
*thread
= get_lwp_thread (lp
);
4282 /* If we get an error after resuming the LWP successfully, we'd
4283 confuse !T state for the LWP being gone. */
4284 gdb_assert (lp
->stopped
);
4286 /* We can't just check whether the LWP is in 'Z (Zombie)' state,
4287 because even if ptrace failed with ESRCH, the tracee may be "not
4288 yet fully dead", but already refusing ptrace requests. In that
4289 case the tracee has 'R (Running)' state for a little bit
4290 (observed in Linux 3.18). See also the note on ESRCH in the
4291 ptrace(2) man page. Instead, check whether the LWP has any state
4292 other than ptrace-stopped. */
4294 /* Don't assume anything if /proc/PID/status can't be read. */
4295 if (linux_proc_pid_is_trace_stopped_nowarn (lwpid_of (thread
)) == 0)
4297 lp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
4298 lp
->status_pending_p
= 0;
4305 linux_process_target::resume_one_lwp (lwp_info
*lwp
, int step
, int signal
,
4310 resume_one_lwp_throw (lwp
, step
, signal
, info
);
4312 catch (const gdb_exception_error
&ex
)
4314 if (!check_ptrace_stopped_lwp_gone (lwp
))
4319 /* This function is called once per thread via for_each_thread.
4320 We look up which resume request applies to THREAD and mark it with a
4321 pointer to the appropriate resume request.
4323 This algorithm is O(threads * resume elements), but resume elements
4324 is small (and will remain small at least until GDB supports thread
4328 linux_set_resume_request (thread_info
*thread
, thread_resume
*resume
, size_t n
)
4330 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4332 for (int ndx
= 0; ndx
< n
; ndx
++)
4334 ptid_t ptid
= resume
[ndx
].thread
;
4335 if (ptid
== minus_one_ptid
4336 || ptid
== thread
->id
4337 /* Handle both 'pPID' and 'pPID.-1' as meaning 'all threads
4339 || (ptid
.pid () == pid_of (thread
)
4341 || ptid
.lwp () == -1)))
4343 if (resume
[ndx
].kind
== resume_stop
4344 && thread
->last_resume_kind
== resume_stop
)
4347 debug_printf ("already %s LWP %ld at GDB's request\n",
4348 (thread
->last_status
.kind ()
4349 == TARGET_WAITKIND_STOPPED
)
4357 /* Ignore (wildcard) resume requests for already-resumed
4359 if (resume
[ndx
].kind
!= resume_stop
4360 && thread
->last_resume_kind
!= resume_stop
)
4363 debug_printf ("already %s LWP %ld at GDB's request\n",
4364 (thread
->last_resume_kind
4372 /* Don't let wildcard resumes resume fork children that GDB
4373 does not yet know are new fork children. */
4374 if (lwp
->fork_relative
!= NULL
)
4376 struct lwp_info
*rel
= lwp
->fork_relative
;
4378 if (rel
->status_pending_p
4379 && (rel
->waitstatus
.kind () == TARGET_WAITKIND_FORKED
4380 || rel
->waitstatus
.kind () == TARGET_WAITKIND_VFORKED
))
4383 debug_printf ("not resuming LWP %ld: has queued stop reply\n",
4389 /* If the thread has a pending event that has already been
4390 reported to GDBserver core, but GDB has not pulled the
4391 event out of the vStopped queue yet, likewise, ignore the
4392 (wildcard) resume request. */
4393 if (in_queued_stop_replies (thread
->id
))
4396 debug_printf ("not resuming LWP %ld: has queued stop reply\n",
4401 lwp
->resume
= &resume
[ndx
];
4402 thread
->last_resume_kind
= lwp
->resume
->kind
;
4404 lwp
->step_range_start
= lwp
->resume
->step_range_start
;
4405 lwp
->step_range_end
= lwp
->resume
->step_range_end
;
4407 /* If we had a deferred signal to report, dequeue one now.
4408 This can happen if LWP gets more than one signal while
4409 trying to get out of a jump pad. */
4411 && !lwp
->status_pending_p
4412 && dequeue_one_deferred_signal (lwp
, &lwp
->status_pending
))
4414 lwp
->status_pending_p
= 1;
4417 debug_printf ("Dequeueing deferred signal %d for LWP %ld, "
4418 "leaving status pending.\n",
4419 WSTOPSIG (lwp
->status_pending
),
4427 /* No resume action for this thread. */
4432 linux_process_target::resume_status_pending (thread_info
*thread
)
4434 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4436 /* LWPs which will not be resumed are not interesting, because
4437 we might not wait for them next time through linux_wait. */
4438 if (lwp
->resume
== NULL
)
4441 return thread_still_has_status_pending (thread
);
4445 linux_process_target::thread_needs_step_over (thread_info
*thread
)
4447 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4448 struct thread_info
*saved_thread
;
4450 struct process_info
*proc
= get_thread_process (thread
);
4452 /* GDBserver is skipping the extra traps from the wrapper program,
4453 don't have to do step over. */
4454 if (proc
->tdesc
== NULL
)
4457 /* LWPs which will not be resumed are not interesting, because we
4458 might not wait for them next time through linux_wait. */
4463 debug_printf ("Need step over [LWP %ld]? Ignoring, not stopped\n",
4468 if (thread
->last_resume_kind
== resume_stop
)
4471 debug_printf ("Need step over [LWP %ld]? Ignoring, should remain"
4477 gdb_assert (lwp
->suspended
>= 0);
4482 debug_printf ("Need step over [LWP %ld]? Ignoring, suspended\n",
4487 if (lwp
->status_pending_p
)
4490 debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
4496 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
4500 /* If the PC has changed since we stopped, then don't do anything,
4501 and let the breakpoint/tracepoint be hit. This happens if, for
4502 instance, GDB handled the decr_pc_after_break subtraction itself,
4503 GDB is OOL stepping this thread, or the user has issued a "jump"
4504 command, or poked thread's registers herself. */
4505 if (pc
!= lwp
->stop_pc
)
4508 debug_printf ("Need step over [LWP %ld]? Cancelling, PC was changed. "
4509 "Old stop_pc was 0x%s, PC is now 0x%s\n",
4511 paddress (lwp
->stop_pc
), paddress (pc
));
4515 /* On software single step target, resume the inferior with signal
4516 rather than stepping over. */
4517 if (supports_software_single_step ()
4518 && !lwp
->pending_signals
.empty ()
4519 && lwp_signal_can_be_delivered (lwp
))
4522 debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
4529 saved_thread
= current_thread
;
4530 current_thread
= thread
;
4532 /* We can only step over breakpoints we know about. */
4533 if (breakpoint_here (pc
) || fast_tracepoint_jump_here (pc
))
4535 /* Don't step over a breakpoint that GDB expects to hit
4536 though. If the condition is being evaluated on the target's side
4537 and it evaluate to false, step over this breakpoint as well. */
4538 if (gdb_breakpoint_here (pc
)
4539 && gdb_condition_true_at_breakpoint (pc
)
4540 && gdb_no_commands_at_breakpoint (pc
))
4543 debug_printf ("Need step over [LWP %ld]? yes, but found"
4544 " GDB breakpoint at 0x%s; skipping step over\n",
4545 lwpid_of (thread
), paddress (pc
));
4547 current_thread
= saved_thread
;
4553 debug_printf ("Need step over [LWP %ld]? yes, "
4554 "found breakpoint at 0x%s\n",
4555 lwpid_of (thread
), paddress (pc
));
4557 /* We've found an lwp that needs stepping over --- return 1 so
4558 that find_thread stops looking. */
4559 current_thread
= saved_thread
;
4565 current_thread
= saved_thread
;
4568 debug_printf ("Need step over [LWP %ld]? No, no breakpoint found"
4570 lwpid_of (thread
), paddress (pc
));
4576 linux_process_target::start_step_over (lwp_info
*lwp
)
4578 struct thread_info
*thread
= get_lwp_thread (lwp
);
4579 struct thread_info
*saved_thread
;
4584 debug_printf ("Starting step-over on LWP %ld. Stopping all threads\n",
4587 stop_all_lwps (1, lwp
);
4589 if (lwp
->suspended
!= 0)
4591 internal_error (__FILE__
, __LINE__
,
4592 "LWP %ld suspended=%d\n", lwpid_of (thread
),
4597 debug_printf ("Done stopping all threads for step-over.\n");
4599 /* Note, we should always reach here with an already adjusted PC,
4600 either by GDB (if we're resuming due to GDB's request), or by our
4601 caller, if we just finished handling an internal breakpoint GDB
4602 shouldn't care about. */
4605 saved_thread
= current_thread
;
4606 current_thread
= thread
;
4608 lwp
->bp_reinsert
= pc
;
4609 uninsert_breakpoints_at (pc
);
4610 uninsert_fast_tracepoint_jumps_at (pc
);
4612 step
= single_step (lwp
);
4614 current_thread
= saved_thread
;
4616 resume_one_lwp (lwp
, step
, 0, NULL
);
4618 /* Require next event from this LWP. */
4619 step_over_bkpt
= thread
->id
;
4623 linux_process_target::finish_step_over (lwp_info
*lwp
)
4625 if (lwp
->bp_reinsert
!= 0)
4627 struct thread_info
*saved_thread
= current_thread
;
4630 debug_printf ("Finished step over.\n");
4632 current_thread
= get_lwp_thread (lwp
);
4634 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
4635 may be no breakpoint to reinsert there by now. */
4636 reinsert_breakpoints_at (lwp
->bp_reinsert
);
4637 reinsert_fast_tracepoint_jumps_at (lwp
->bp_reinsert
);
4639 lwp
->bp_reinsert
= 0;
4641 /* Delete any single-step breakpoints. No longer needed. We
4642 don't have to worry about other threads hitting this trap,
4643 and later not being able to explain it, because we were
4644 stepping over a breakpoint, and we hold all threads but
4645 LWP stopped while doing that. */
4646 if (!supports_hardware_single_step ())
4648 gdb_assert (has_single_step_breakpoints (current_thread
));
4649 delete_single_step_breakpoints (current_thread
);
4652 step_over_bkpt
= null_ptid
;
4653 current_thread
= saved_thread
;
4661 linux_process_target::complete_ongoing_step_over ()
4663 if (step_over_bkpt
!= null_ptid
)
4665 struct lwp_info
*lwp
;
4670 debug_printf ("detach: step over in progress, finish it first\n");
4672 /* Passing NULL_PTID as filter indicates we want all events to
4673 be left pending. Eventually this returns when there are no
4674 unwaited-for children left. */
4675 ret
= wait_for_event_filtered (minus_one_ptid
, null_ptid
, &wstat
,
4677 gdb_assert (ret
== -1);
4679 lwp
= find_lwp_pid (step_over_bkpt
);
4682 finish_step_over (lwp
);
4684 /* If we got our step SIGTRAP, don't leave it pending,
4685 otherwise we would report it to GDB as a spurious
4687 gdb_assert (lwp
->status_pending_p
);
4688 if (WIFSTOPPED (lwp
->status_pending
)
4689 && WSTOPSIG (lwp
->status_pending
) == SIGTRAP
)
4691 thread_info
*thread
= get_lwp_thread (lwp
);
4692 if (thread
->last_resume_kind
!= resume_step
)
4695 debug_printf ("detach: discard step-over SIGTRAP\n");
4697 lwp
->status_pending_p
= 0;
4698 lwp
->status_pending
= 0;
4699 resume_one_lwp (lwp
, lwp
->stepping
, 0, NULL
);
4704 debug_printf ("detach: resume_step, "
4705 "not discarding step-over SIGTRAP\n");
4709 step_over_bkpt
= null_ptid
;
4710 unsuspend_all_lwps (lwp
);
4715 linux_process_target::resume_one_thread (thread_info
*thread
,
4716 bool leave_all_stopped
)
4718 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4721 if (lwp
->resume
== NULL
)
4724 if (lwp
->resume
->kind
== resume_stop
)
4727 debug_printf ("resume_stop request for LWP %ld\n", lwpid_of (thread
));
4732 debug_printf ("stopping LWP %ld\n", lwpid_of (thread
));
4734 /* Stop the thread, and wait for the event asynchronously,
4735 through the event loop. */
4741 debug_printf ("already stopped LWP %ld\n",
4744 /* The LWP may have been stopped in an internal event that
4745 was not meant to be notified back to GDB (e.g., gdbserver
4746 breakpoint), so we should be reporting a stop event in
4749 /* If the thread already has a pending SIGSTOP, this is a
4750 no-op. Otherwise, something later will presumably resume
4751 the thread and this will cause it to cancel any pending
4752 operation, due to last_resume_kind == resume_stop. If
4753 the thread already has a pending status to report, we
4754 will still report it the next time we wait - see
4755 status_pending_p_callback. */
4757 /* If we already have a pending signal to report, then
4758 there's no need to queue a SIGSTOP, as this means we're
4759 midway through moving the LWP out of the jumppad, and we
4760 will report the pending signal as soon as that is
4762 if (lwp
->pending_signals_to_report
.empty ())
4766 /* For stop requests, we're done. */
4768 thread
->last_status
.set_ignore ();
4772 /* If this thread which is about to be resumed has a pending status,
4773 then don't resume it - we can just report the pending status.
4774 Likewise if it is suspended, because e.g., another thread is
4775 stepping past a breakpoint. Make sure to queue any signals that
4776 would otherwise be sent. In all-stop mode, we do this decision
4777 based on if *any* thread has a pending status. If there's a
4778 thread that needs the step-over-breakpoint dance, then don't
4779 resume any other thread but that particular one. */
4780 leave_pending
= (lwp
->suspended
4781 || lwp
->status_pending_p
4782 || leave_all_stopped
);
4784 /* If we have a new signal, enqueue the signal. */
4785 if (lwp
->resume
->sig
!= 0)
4787 siginfo_t info
, *info_p
;
4789 /* If this is the same signal we were previously stopped by,
4790 make sure to queue its siginfo. */
4791 if (WIFSTOPPED (lwp
->last_status
)
4792 && WSTOPSIG (lwp
->last_status
) == lwp
->resume
->sig
4793 && ptrace (PTRACE_GETSIGINFO
, lwpid_of (thread
),
4794 (PTRACE_TYPE_ARG3
) 0, &info
) == 0)
4799 enqueue_pending_signal (lwp
, lwp
->resume
->sig
, info_p
);
4805 debug_printf ("resuming LWP %ld\n", lwpid_of (thread
));
4807 proceed_one_lwp (thread
, NULL
);
4812 debug_printf ("leaving LWP %ld stopped\n", lwpid_of (thread
));
4815 thread
->last_status
.set_ignore ();
4820 linux_process_target::resume (thread_resume
*resume_info
, size_t n
)
4822 struct thread_info
*need_step_over
= NULL
;
4827 debug_printf ("linux_resume:\n");
4830 for_each_thread ([&] (thread_info
*thread
)
4832 linux_set_resume_request (thread
, resume_info
, n
);
4835 /* If there is a thread which would otherwise be resumed, which has
4836 a pending status, then don't resume any threads - we can just
4837 report the pending status. Make sure to queue any signals that
4838 would otherwise be sent. In non-stop mode, we'll apply this
4839 logic to each thread individually. We consume all pending events
4840 before considering to start a step-over (in all-stop). */
4841 bool any_pending
= false;
4843 any_pending
= find_thread ([this] (thread_info
*thread
)
4845 return resume_status_pending (thread
);
4848 /* If there is a thread which would otherwise be resumed, which is
4849 stopped at a breakpoint that needs stepping over, then don't
4850 resume any threads - have it step over the breakpoint with all
4851 other threads stopped, then resume all threads again. Make sure
4852 to queue any signals that would otherwise be delivered or
4854 if (!any_pending
&& low_supports_breakpoints ())
4855 need_step_over
= find_thread ([this] (thread_info
*thread
)
4857 return thread_needs_step_over (thread
);
4860 bool leave_all_stopped
= (need_step_over
!= NULL
|| any_pending
);
4864 if (need_step_over
!= NULL
)
4865 debug_printf ("Not resuming all, need step over\n");
4866 else if (any_pending
)
4867 debug_printf ("Not resuming, all-stop and found "
4868 "an LWP with pending status\n");
4870 debug_printf ("Resuming, no pending status or step over needed\n");
4873 /* Even if we're leaving threads stopped, queue all signals we'd
4874 otherwise deliver. */
4875 for_each_thread ([&] (thread_info
*thread
)
4877 resume_one_thread (thread
, leave_all_stopped
);
4881 start_step_over (get_thread_lwp (need_step_over
));
4885 debug_printf ("linux_resume done\n");
4889 /* We may have events that were pending that can/should be sent to
4890 the client now. Trigger a linux_wait call. */
4891 if (target_is_async_p ())
4896 linux_process_target::proceed_one_lwp (thread_info
*thread
, lwp_info
*except
)
4898 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4905 debug_printf ("proceed_one_lwp: lwp %ld\n", lwpid_of (thread
));
4910 debug_printf (" LWP %ld already running\n", lwpid_of (thread
));
4914 if (thread
->last_resume_kind
== resume_stop
4915 && thread
->last_status
.kind () != TARGET_WAITKIND_IGNORE
)
4918 debug_printf (" client wants LWP to remain %ld stopped\n",
4923 if (lwp
->status_pending_p
)
4926 debug_printf (" LWP %ld has pending status, leaving stopped\n",
4931 gdb_assert (lwp
->suspended
>= 0);
4936 debug_printf (" LWP %ld is suspended\n", lwpid_of (thread
));
4940 if (thread
->last_resume_kind
== resume_stop
4941 && lwp
->pending_signals_to_report
.empty ()
4942 && (lwp
->collecting_fast_tracepoint
4943 == fast_tpoint_collect_result::not_collecting
))
4945 /* We haven't reported this LWP as stopped yet (otherwise, the
4946 last_status.kind check above would catch it, and we wouldn't
4947 reach here. This LWP may have been momentarily paused by a
4948 stop_all_lwps call while handling for example, another LWP's
4949 step-over. In that case, the pending expected SIGSTOP signal
4950 that was queued at vCont;t handling time will have already
4951 been consumed by wait_for_sigstop, and so we need to requeue
4952 another one here. Note that if the LWP already has a SIGSTOP
4953 pending, this is a no-op. */
4956 debug_printf ("Client wants LWP %ld to stop. "
4957 "Making sure it has a SIGSTOP pending\n",
4963 if (thread
->last_resume_kind
== resume_step
)
4966 debug_printf (" stepping LWP %ld, client wants it stepping\n",
4969 /* If resume_step is requested by GDB, install single-step
4970 breakpoints when the thread is about to be actually resumed if
4971 the single-step breakpoints weren't removed. */
4972 if (supports_software_single_step ()
4973 && !has_single_step_breakpoints (thread
))
4974 install_software_single_step_breakpoints (lwp
);
4976 step
= maybe_hw_step (thread
);
4978 else if (lwp
->bp_reinsert
!= 0)
4981 debug_printf (" stepping LWP %ld, reinsert set\n",
4984 step
= maybe_hw_step (thread
);
4989 resume_one_lwp (lwp
, step
, 0, NULL
);
4993 linux_process_target::unsuspend_and_proceed_one_lwp (thread_info
*thread
,
4996 struct lwp_info
*lwp
= get_thread_lwp (thread
);
5001 lwp_suspended_decr (lwp
);
5003 proceed_one_lwp (thread
, except
);
5007 linux_process_target::proceed_all_lwps ()
5009 struct thread_info
*need_step_over
;
5011 /* If there is a thread which would otherwise be resumed, which is
5012 stopped at a breakpoint that needs stepping over, then don't
5013 resume any threads - have it step over the breakpoint with all
5014 other threads stopped, then resume all threads again. */
5016 if (low_supports_breakpoints ())
5018 need_step_over
= find_thread ([this] (thread_info
*thread
)
5020 return thread_needs_step_over (thread
);
5023 if (need_step_over
!= NULL
)
5026 debug_printf ("proceed_all_lwps: found "
5027 "thread %ld needing a step-over\n",
5028 lwpid_of (need_step_over
));
5030 start_step_over (get_thread_lwp (need_step_over
));
5036 debug_printf ("Proceeding, no step-over needed\n");
5038 for_each_thread ([this] (thread_info
*thread
)
5040 proceed_one_lwp (thread
, NULL
);
5045 linux_process_target::unstop_all_lwps (int unsuspend
, lwp_info
*except
)
5051 debug_printf ("unstopping all lwps, except=(LWP %ld)\n",
5052 lwpid_of (get_lwp_thread (except
)));
5054 debug_printf ("unstopping all lwps\n");
5058 for_each_thread ([&] (thread_info
*thread
)
5060 unsuspend_and_proceed_one_lwp (thread
, except
);
5063 for_each_thread ([&] (thread_info
*thread
)
5065 proceed_one_lwp (thread
, except
);
5070 debug_printf ("unstop_all_lwps done\n");
5076 #ifdef HAVE_LINUX_REGSETS
5078 #define use_linux_regsets 1
5080 /* Returns true if REGSET has been disabled. */
5083 regset_disabled (struct regsets_info
*info
, struct regset_info
*regset
)
5085 return (info
->disabled_regsets
!= NULL
5086 && info
->disabled_regsets
[regset
- info
->regsets
]);
5089 /* Disable REGSET. */
5092 disable_regset (struct regsets_info
*info
, struct regset_info
*regset
)
5096 dr_offset
= regset
- info
->regsets
;
5097 if (info
->disabled_regsets
== NULL
)
5098 info
->disabled_regsets
= (char *) xcalloc (1, info
->num_regsets
);
5099 info
->disabled_regsets
[dr_offset
] = 1;
5103 regsets_fetch_inferior_registers (struct regsets_info
*regsets_info
,
5104 struct regcache
*regcache
)
5106 struct regset_info
*regset
;
5107 int saw_general_regs
= 0;
5111 pid
= lwpid_of (current_thread
);
5112 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
5117 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
))
5120 buf
= xmalloc (regset
->size
);
5122 nt_type
= regset
->nt_type
;
5126 iov
.iov_len
= regset
->size
;
5127 data
= (void *) &iov
;
5133 res
= ptrace (regset
->get_request
, pid
,
5134 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5136 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
5141 || (errno
== EINVAL
&& regset
->type
== OPTIONAL_REGS
))
5143 /* If we get EIO on a regset, or an EINVAL and the regset is
5144 optional, do not try it again for this process mode. */
5145 disable_regset (regsets_info
, regset
);
5147 else if (errno
== ENODATA
)
5149 /* ENODATA may be returned if the regset is currently
5150 not "active". This can happen in normal operation,
5151 so suppress the warning in this case. */
5153 else if (errno
== ESRCH
)
5155 /* At this point, ESRCH should mean the process is
5156 already gone, in which case we simply ignore attempts
5157 to read its registers. */
5162 sprintf (s
, "ptrace(regsets_fetch_inferior_registers) PID=%d",
5169 if (regset
->type
== GENERAL_REGS
)
5170 saw_general_regs
= 1;
5171 regset
->store_function (regcache
, buf
);
5175 if (saw_general_regs
)
5182 regsets_store_inferior_registers (struct regsets_info
*regsets_info
,
5183 struct regcache
*regcache
)
5185 struct regset_info
*regset
;
5186 int saw_general_regs
= 0;
5190 pid
= lwpid_of (current_thread
);
5191 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
5196 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
)
5197 || regset
->fill_function
== NULL
)
5200 buf
= xmalloc (regset
->size
);
5202 /* First fill the buffer with the current register set contents,
5203 in case there are any items in the kernel's regset that are
5204 not in gdbserver's regcache. */
5206 nt_type
= regset
->nt_type
;
5210 iov
.iov_len
= regset
->size
;
5211 data
= (void *) &iov
;
5217 res
= ptrace (regset
->get_request
, pid
,
5218 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5220 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
5225 /* Then overlay our cached registers on that. */
5226 regset
->fill_function (regcache
, buf
);
5228 /* Only now do we write the register set. */
5230 res
= ptrace (regset
->set_request
, pid
,
5231 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5233 res
= ptrace (regset
->set_request
, pid
, data
, nt_type
);
5240 || (errno
== EINVAL
&& regset
->type
== OPTIONAL_REGS
))
5242 /* If we get EIO on a regset, or an EINVAL and the regset is
5243 optional, do not try it again for this process mode. */
5244 disable_regset (regsets_info
, regset
);
5246 else if (errno
== ESRCH
)
5248 /* At this point, ESRCH should mean the process is
5249 already gone, in which case we simply ignore attempts
5250 to change its registers. See also the related
5251 comment in resume_one_lwp. */
5257 perror ("Warning: ptrace(regsets_store_inferior_registers)");
5260 else if (regset
->type
== GENERAL_REGS
)
5261 saw_general_regs
= 1;
5264 if (saw_general_regs
)
5270 #else /* !HAVE_LINUX_REGSETS */
5272 #define use_linux_regsets 0
5273 #define regsets_fetch_inferior_registers(regsets_info, regcache) 1
5274 #define regsets_store_inferior_registers(regsets_info, regcache) 1
5278 /* Return 1 if register REGNO is supported by one of the regset ptrace
5279 calls or 0 if it has to be transferred individually. */
5282 linux_register_in_regsets (const struct regs_info
*regs_info
, int regno
)
5284 unsigned char mask
= 1 << (regno
% 8);
5285 size_t index
= regno
/ 8;
5287 return (use_linux_regsets
5288 && (regs_info
->regset_bitmap
== NULL
5289 || (regs_info
->regset_bitmap
[index
] & mask
) != 0));
5292 #ifdef HAVE_LINUX_USRREGS
5295 register_addr (const struct usrregs_info
*usrregs
, int regnum
)
5299 if (regnum
< 0 || regnum
>= usrregs
->num_regs
)
5300 error ("Invalid register number %d.", regnum
);
5302 addr
= usrregs
->regmap
[regnum
];
5309 linux_process_target::fetch_register (const usrregs_info
*usrregs
,
5310 regcache
*regcache
, int regno
)
5317 if (regno
>= usrregs
->num_regs
)
5319 if (low_cannot_fetch_register (regno
))
5322 regaddr
= register_addr (usrregs
, regno
);
5326 size
= ((register_size (regcache
->tdesc
, regno
)
5327 + sizeof (PTRACE_XFER_TYPE
) - 1)
5328 & -sizeof (PTRACE_XFER_TYPE
));
5329 buf
= (char *) alloca (size
);
5331 pid
= lwpid_of (current_thread
);
5332 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
5335 *(PTRACE_XFER_TYPE
*) (buf
+ i
) =
5336 ptrace (PTRACE_PEEKUSER
, pid
,
5337 /* Coerce to a uintptr_t first to avoid potential gcc warning
5338 of coercing an 8 byte integer to a 4 byte pointer. */
5339 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
, (PTRACE_TYPE_ARG4
) 0);
5340 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
5343 /* Mark register REGNO unavailable. */
5344 supply_register (regcache
, regno
, NULL
);
5349 low_supply_ptrace_register (regcache
, regno
, buf
);
5353 linux_process_target::store_register (const usrregs_info
*usrregs
,
5354 regcache
*regcache
, int regno
)
5361 if (regno
>= usrregs
->num_regs
)
5363 if (low_cannot_store_register (regno
))
5366 regaddr
= register_addr (usrregs
, regno
);
5370 size
= ((register_size (regcache
->tdesc
, regno
)
5371 + sizeof (PTRACE_XFER_TYPE
) - 1)
5372 & -sizeof (PTRACE_XFER_TYPE
));
5373 buf
= (char *) alloca (size
);
5374 memset (buf
, 0, size
);
5376 low_collect_ptrace_register (regcache
, regno
, buf
);
5378 pid
= lwpid_of (current_thread
);
5379 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
5382 ptrace (PTRACE_POKEUSER
, pid
,
5383 /* Coerce to a uintptr_t first to avoid potential gcc warning
5384 about coercing an 8 byte integer to a 4 byte pointer. */
5385 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
,
5386 (PTRACE_TYPE_ARG4
) *(PTRACE_XFER_TYPE
*) (buf
+ i
));
5389 /* At this point, ESRCH should mean the process is
5390 already gone, in which case we simply ignore attempts
5391 to change its registers. See also the related
5392 comment in resume_one_lwp. */
5397 if (!low_cannot_store_register (regno
))
5398 error ("writing register %d: %s", regno
, safe_strerror (errno
));
5400 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
5403 #endif /* HAVE_LINUX_USRREGS */
5406 linux_process_target::low_collect_ptrace_register (regcache
*regcache
,
5407 int regno
, char *buf
)
5409 collect_register (regcache
, regno
, buf
);
5413 linux_process_target::low_supply_ptrace_register (regcache
*regcache
,
5414 int regno
, const char *buf
)
5416 supply_register (regcache
, regno
, buf
);
5420 linux_process_target::usr_fetch_inferior_registers (const regs_info
*regs_info
,
5424 #ifdef HAVE_LINUX_USRREGS
5425 struct usrregs_info
*usr
= regs_info
->usrregs
;
5429 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
5430 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
5431 fetch_register (usr
, regcache
, regno
);
5434 fetch_register (usr
, regcache
, regno
);
5439 linux_process_target::usr_store_inferior_registers (const regs_info
*regs_info
,
5443 #ifdef HAVE_LINUX_USRREGS
5444 struct usrregs_info
*usr
= regs_info
->usrregs
;
5448 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
5449 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
5450 store_register (usr
, regcache
, regno
);
5453 store_register (usr
, regcache
, regno
);
5458 linux_process_target::fetch_registers (regcache
*regcache
, int regno
)
5462 const regs_info
*regs_info
= get_regs_info ();
5466 if (regs_info
->usrregs
!= NULL
)
5467 for (regno
= 0; regno
< regs_info
->usrregs
->num_regs
; regno
++)
5468 low_fetch_register (regcache
, regno
);
5470 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
, regcache
);
5471 if (regs_info
->usrregs
!= NULL
)
5472 usr_fetch_inferior_registers (regs_info
, regcache
, -1, all
);
5476 if (low_fetch_register (regcache
, regno
))
5479 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
5481 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
,
5483 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
5484 usr_fetch_inferior_registers (regs_info
, regcache
, regno
, 1);
5489 linux_process_target::store_registers (regcache
*regcache
, int regno
)
5493 const regs_info
*regs_info
= get_regs_info ();
5497 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
5499 if (regs_info
->usrregs
!= NULL
)
5500 usr_store_inferior_registers (regs_info
, regcache
, regno
, all
);
5504 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
5506 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
5508 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
5509 usr_store_inferior_registers (regs_info
, regcache
, regno
, 1);
5514 linux_process_target::low_fetch_register (regcache
*regcache
, int regno
)
5519 /* A wrapper for the read_memory target op. */
5522 linux_read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
, int len
)
5524 return the_target
->read_memory (memaddr
, myaddr
, len
);
5527 /* Copy LEN bytes from inferior's memory starting at MEMADDR
5528 to debugger memory starting at MYADDR. */
5531 linux_process_target::read_memory (CORE_ADDR memaddr
,
5532 unsigned char *myaddr
, int len
)
5534 int pid
= lwpid_of (current_thread
);
5535 PTRACE_XFER_TYPE
*buffer
;
5543 /* Try using /proc. Don't bother for one word. */
5544 if (len
>= 3 * sizeof (long))
5548 /* We could keep this file open and cache it - possibly one per
5549 thread. That requires some juggling, but is even faster. */
5550 sprintf (filename
, "/proc/%d/mem", pid
);
5551 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
5555 /* If pread64 is available, use it. It's faster if the kernel
5556 supports it (only one syscall), and it's 64-bit safe even on
5557 32-bit platforms (for instance, SPARC debugging a SPARC64
5560 bytes
= pread64 (fd
, myaddr
, len
, memaddr
);
5563 if (lseek (fd
, memaddr
, SEEK_SET
) != -1)
5564 bytes
= read (fd
, myaddr
, len
);
5571 /* Some data was read, we'll try to get the rest with ptrace. */
5581 /* Round starting address down to longword boundary. */
5582 addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
5583 /* Round ending address up; get number of longwords that makes. */
5584 count
= ((((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
5585 / sizeof (PTRACE_XFER_TYPE
));
5586 /* Allocate buffer of that many longwords. */
5587 buffer
= XALLOCAVEC (PTRACE_XFER_TYPE
, count
);
5589 /* Read all the longwords */
5591 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
5593 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5594 about coercing an 8 byte integer to a 4 byte pointer. */
5595 buffer
[i
] = ptrace (PTRACE_PEEKTEXT
, pid
,
5596 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5597 (PTRACE_TYPE_ARG4
) 0);
5603 /* Copy appropriate bytes out of the buffer. */
5606 i
*= sizeof (PTRACE_XFER_TYPE
);
5607 i
-= memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1);
5609 (char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
5616 /* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
5617 memory at MEMADDR. On failure (cannot write to the inferior)
5618 returns the value of errno. Always succeeds if LEN is zero. */
5621 linux_process_target::write_memory (CORE_ADDR memaddr
,
5622 const unsigned char *myaddr
, int len
)
5625 /* Round starting address down to longword boundary. */
5626 CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
5627 /* Round ending address up; get number of longwords that makes. */
5629 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
5630 / sizeof (PTRACE_XFER_TYPE
);
5632 /* Allocate buffer of that many longwords. */
5633 PTRACE_XFER_TYPE
*buffer
= XALLOCAVEC (PTRACE_XFER_TYPE
, count
);
5635 int pid
= lwpid_of (current_thread
);
5639 /* Zero length write always succeeds. */
5645 /* Dump up to four bytes. */
5646 char str
[4 * 2 + 1];
5648 int dump
= len
< 4 ? len
: 4;
5650 for (i
= 0; i
< dump
; i
++)
5652 sprintf (p
, "%02x", myaddr
[i
]);
5657 debug_printf ("Writing %s to 0x%08lx in process %d\n",
5658 str
, (long) memaddr
, pid
);
5661 /* Fill start and end extra bytes of buffer with existing memory data. */
5664 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5665 about coercing an 8 byte integer to a 4 byte pointer. */
5666 buffer
[0] = ptrace (PTRACE_PEEKTEXT
, pid
,
5667 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5668 (PTRACE_TYPE_ARG4
) 0);
5676 = ptrace (PTRACE_PEEKTEXT
, pid
,
5677 /* Coerce to a uintptr_t first to avoid potential gcc warning
5678 about coercing an 8 byte integer to a 4 byte pointer. */
5679 (PTRACE_TYPE_ARG3
) (uintptr_t) (addr
+ (count
- 1)
5680 * sizeof (PTRACE_XFER_TYPE
)),
5681 (PTRACE_TYPE_ARG4
) 0);
5686 /* Copy data to be written over corresponding part of buffer. */
5688 memcpy ((char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
5691 /* Write the entire buffer. */
5693 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
5696 ptrace (PTRACE_POKETEXT
, pid
,
5697 /* Coerce to a uintptr_t first to avoid potential gcc warning
5698 about coercing an 8 byte integer to a 4 byte pointer. */
5699 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5700 (PTRACE_TYPE_ARG4
) buffer
[i
]);
5709 linux_process_target::look_up_symbols ()
5711 #ifdef USE_THREAD_DB
5712 struct process_info
*proc
= current_process ();
5714 if (proc
->priv
->thread_db
!= NULL
)
5722 linux_process_target::request_interrupt ()
5724 /* Send a SIGINT to the process group. This acts just like the user
5725 typed a ^C on the controlling terminal. */
5726 ::kill (-signal_pid
, SIGINT
);
5730 linux_process_target::supports_read_auxv ()
5735 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
5736 to debugger memory starting at MYADDR. */
5739 linux_process_target::read_auxv (CORE_ADDR offset
, unsigned char *myaddr
,
5742 char filename
[PATH_MAX
];
5744 int pid
= lwpid_of (current_thread
);
5746 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
5748 fd
= open (filename
, O_RDONLY
);
5752 if (offset
!= (CORE_ADDR
) 0
5753 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
5756 n
= read (fd
, myaddr
, len
);
5764 linux_process_target::insert_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
5765 int size
, raw_breakpoint
*bp
)
5767 if (type
== raw_bkpt_type_sw
)
5768 return insert_memory_breakpoint (bp
);
5770 return low_insert_point (type
, addr
, size
, bp
);
5774 linux_process_target::low_insert_point (raw_bkpt_type type
, CORE_ADDR addr
,
5775 int size
, raw_breakpoint
*bp
)
5777 /* Unsupported (see target.h). */
5782 linux_process_target::remove_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
5783 int size
, raw_breakpoint
*bp
)
5785 if (type
== raw_bkpt_type_sw
)
5786 return remove_memory_breakpoint (bp
);
5788 return low_remove_point (type
, addr
, size
, bp
);
5792 linux_process_target::low_remove_point (raw_bkpt_type type
, CORE_ADDR addr
,
5793 int size
, raw_breakpoint
*bp
)
5795 /* Unsupported (see target.h). */
5799 /* Implement the stopped_by_sw_breakpoint target_ops
5803 linux_process_target::stopped_by_sw_breakpoint ()
5805 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5807 return (lwp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
);
5810 /* Implement the supports_stopped_by_sw_breakpoint target_ops
5814 linux_process_target::supports_stopped_by_sw_breakpoint ()
5816 return USE_SIGTRAP_SIGINFO
;
5819 /* Implement the stopped_by_hw_breakpoint target_ops
5823 linux_process_target::stopped_by_hw_breakpoint ()
5825 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5827 return (lwp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
);
5830 /* Implement the supports_stopped_by_hw_breakpoint target_ops
5834 linux_process_target::supports_stopped_by_hw_breakpoint ()
5836 return USE_SIGTRAP_SIGINFO
;
5839 /* Implement the supports_hardware_single_step target_ops method. */
5842 linux_process_target::supports_hardware_single_step ()
5848 linux_process_target::stopped_by_watchpoint ()
5850 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5852 return lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
;
5856 linux_process_target::stopped_data_address ()
5858 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5860 return lwp
->stopped_data_address
;
5863 /* This is only used for targets that define PT_TEXT_ADDR,
5864 PT_DATA_ADDR and PT_TEXT_END_ADDR. If those are not defined, supposedly
5865 the target has different ways of acquiring this information, like
5869 linux_process_target::supports_read_offsets ()
5871 #ifdef SUPPORTS_READ_OFFSETS
5878 /* Under uClinux, programs are loaded at non-zero offsets, which we need
5879 to tell gdb about. */
5882 linux_process_target::read_offsets (CORE_ADDR
*text_p
, CORE_ADDR
*data_p
)
5884 #ifdef SUPPORTS_READ_OFFSETS
5885 unsigned long text
, text_end
, data
;
5886 int pid
= lwpid_of (current_thread
);
5890 text
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_ADDR
,
5891 (PTRACE_TYPE_ARG4
) 0);
5892 text_end
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_END_ADDR
,
5893 (PTRACE_TYPE_ARG4
) 0);
5894 data
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_DATA_ADDR
,
5895 (PTRACE_TYPE_ARG4
) 0);
5899 /* Both text and data offsets produced at compile-time (and so
5900 used by gdb) are relative to the beginning of the program,
5901 with the data segment immediately following the text segment.
5902 However, the actual runtime layout in memory may put the data
5903 somewhere else, so when we send gdb a data base-address, we
5904 use the real data base address and subtract the compile-time
5905 data base-address from it (which is just the length of the
5906 text segment). BSS immediately follows data in both
5909 *data_p
= data
- (text_end
- text
);
5915 gdb_assert_not_reached ("target op read_offsets not supported");
5920 linux_process_target::supports_get_tls_address ()
5922 #ifdef USE_THREAD_DB
5930 linux_process_target::get_tls_address (thread_info
*thread
,
5932 CORE_ADDR load_module
,
5935 #ifdef USE_THREAD_DB
5936 return thread_db_get_tls_address (thread
, offset
, load_module
, address
);
5943 linux_process_target::supports_qxfer_osdata ()
5949 linux_process_target::qxfer_osdata (const char *annex
,
5950 unsigned char *readbuf
,
5951 unsigned const char *writebuf
,
5952 CORE_ADDR offset
, int len
)
5954 return linux_common_xfer_osdata (annex
, readbuf
, offset
, len
);
5958 linux_process_target::siginfo_fixup (siginfo_t
*siginfo
,
5959 gdb_byte
*inf_siginfo
, int direction
)
5961 bool done
= low_siginfo_fixup (siginfo
, inf_siginfo
, direction
);
5963 /* If there was no callback, or the callback didn't do anything,
5964 then just do a straight memcpy. */
5968 memcpy (siginfo
, inf_siginfo
, sizeof (siginfo_t
));
5970 memcpy (inf_siginfo
, siginfo
, sizeof (siginfo_t
));
5975 linux_process_target::low_siginfo_fixup (siginfo_t
*native
, gdb_byte
*inf
,
5982 linux_process_target::supports_qxfer_siginfo ()
5988 linux_process_target::qxfer_siginfo (const char *annex
,
5989 unsigned char *readbuf
,
5990 unsigned const char *writebuf
,
5991 CORE_ADDR offset
, int len
)
5995 gdb_byte inf_siginfo
[sizeof (siginfo_t
)];
5997 if (current_thread
== NULL
)
6000 pid
= lwpid_of (current_thread
);
6003 debug_printf ("%s siginfo for lwp %d.\n",
6004 readbuf
!= NULL
? "Reading" : "Writing",
6007 if (offset
>= sizeof (siginfo
))
6010 if (ptrace (PTRACE_GETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
6013 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
6014 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
6015 inferior with a 64-bit GDBSERVER should look the same as debugging it
6016 with a 32-bit GDBSERVER, we need to convert it. */
6017 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
6019 if (offset
+ len
> sizeof (siginfo
))
6020 len
= sizeof (siginfo
) - offset
;
6022 if (readbuf
!= NULL
)
6023 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
6026 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
6028 /* Convert back to ptrace layout before flushing it out. */
6029 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
6031 if (ptrace (PTRACE_SETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
6038 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
6039 so we notice when children change state; as the handler for the
6040 sigsuspend in my_waitpid. */
6043 sigchld_handler (int signo
)
6045 int old_errno
= errno
;
6051 /* Use the async signal safe debug function. */
6052 if (debug_write ("sigchld_handler\n",
6053 sizeof ("sigchld_handler\n") - 1) < 0)
6054 break; /* just ignore */
6058 if (target_is_async_p ())
6059 async_file_mark (); /* trigger a linux_wait */
6065 linux_process_target::supports_non_stop ()
6071 linux_process_target::async (bool enable
)
6073 bool previous
= target_is_async_p ();
6076 debug_printf ("linux_async (%d), previous=%d\n",
6079 if (previous
!= enable
)
6082 sigemptyset (&mask
);
6083 sigaddset (&mask
, SIGCHLD
);
6085 gdb_sigmask (SIG_BLOCK
, &mask
, NULL
);
6089 if (pipe (linux_event_pipe
) == -1)
6091 linux_event_pipe
[0] = -1;
6092 linux_event_pipe
[1] = -1;
6093 gdb_sigmask (SIG_UNBLOCK
, &mask
, NULL
);
6095 warning ("creating event pipe failed.");
6099 fcntl (linux_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
6100 fcntl (linux_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
6102 /* Register the event loop handler. */
6103 add_file_handler (linux_event_pipe
[0],
6104 handle_target_event
, NULL
,
6107 /* Always trigger a linux_wait. */
6112 delete_file_handler (linux_event_pipe
[0]);
6114 close (linux_event_pipe
[0]);
6115 close (linux_event_pipe
[1]);
6116 linux_event_pipe
[0] = -1;
6117 linux_event_pipe
[1] = -1;
6120 gdb_sigmask (SIG_UNBLOCK
, &mask
, NULL
);
6127 linux_process_target::start_non_stop (bool nonstop
)
6129 /* Register or unregister from event-loop accordingly. */
6130 target_async (nonstop
);
6132 if (target_is_async_p () != (nonstop
!= false))
6139 linux_process_target::supports_multi_process ()
6144 /* Check if fork events are supported. */
6147 linux_process_target::supports_fork_events ()
6149 return linux_supports_tracefork ();
6152 /* Check if vfork events are supported. */
6155 linux_process_target::supports_vfork_events ()
6157 return linux_supports_tracefork ();
6160 /* Check if exec events are supported. */
6163 linux_process_target::supports_exec_events ()
6165 return linux_supports_traceexec ();
6168 /* Target hook for 'handle_new_gdb_connection'. Causes a reset of the
6169 ptrace flags for all inferiors. This is in case the new GDB connection
6170 doesn't support the same set of events that the previous one did. */
6173 linux_process_target::handle_new_gdb_connection ()
6175 /* Request that all the lwps reset their ptrace options. */
6176 for_each_thread ([] (thread_info
*thread
)
6178 struct lwp_info
*lwp
= get_thread_lwp (thread
);
6182 /* Stop the lwp so we can modify its ptrace options. */
6183 lwp
->must_set_ptrace_flags
= 1;
6184 linux_stop_lwp (lwp
);
6188 /* Already stopped; go ahead and set the ptrace options. */
6189 struct process_info
*proc
= find_process_pid (pid_of (thread
));
6190 int options
= linux_low_ptrace_options (proc
->attached
);
6192 linux_enable_event_reporting (lwpid_of (thread
), options
);
6193 lwp
->must_set_ptrace_flags
= 0;
6199 linux_process_target::handle_monitor_command (char *mon
)
6201 #ifdef USE_THREAD_DB
6202 return thread_db_handle_monitor_command (mon
);
6209 linux_process_target::core_of_thread (ptid_t ptid
)
6211 return linux_common_core_of_thread (ptid
);
6215 linux_process_target::supports_disable_randomization ()
6221 linux_process_target::supports_agent ()
6227 linux_process_target::supports_range_stepping ()
6229 if (supports_software_single_step ())
6232 return low_supports_range_stepping ();
6236 linux_process_target::low_supports_range_stepping ()
6242 linux_process_target::supports_pid_to_exec_file ()
6248 linux_process_target::pid_to_exec_file (int pid
)
6250 return linux_proc_pid_to_exec_file (pid
);
6254 linux_process_target::supports_multifs ()
6260 linux_process_target::multifs_open (int pid
, const char *filename
,
6261 int flags
, mode_t mode
)
6263 return linux_mntns_open_cloexec (pid
, filename
, flags
, mode
);
6267 linux_process_target::multifs_unlink (int pid
, const char *filename
)
6269 return linux_mntns_unlink (pid
, filename
);
6273 linux_process_target::multifs_readlink (int pid
, const char *filename
,
6274 char *buf
, size_t bufsiz
)
6276 return linux_mntns_readlink (pid
, filename
, buf
, bufsiz
);
6279 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
6280 struct target_loadseg
6282 /* Core address to which the segment is mapped. */
6284 /* VMA recorded in the program header. */
6286 /* Size of this segment in memory. */
6290 # if defined PT_GETDSBT
6291 struct target_loadmap
6293 /* Protocol version number, must be zero. */
6295 /* Pointer to the DSBT table, its size, and the DSBT index. */
6296 unsigned *dsbt_table
;
6297 unsigned dsbt_size
, dsbt_index
;
6298 /* Number of segments in this map. */
6300 /* The actual memory map. */
6301 struct target_loadseg segs
[/*nsegs*/];
6303 # define LINUX_LOADMAP PT_GETDSBT
6304 # define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
6305 # define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
6307 struct target_loadmap
6309 /* Protocol version number, must be zero. */
6311 /* Number of segments in this map. */
6313 /* The actual memory map. */
6314 struct target_loadseg segs
[/*nsegs*/];
6316 # define LINUX_LOADMAP PTRACE_GETFDPIC
6317 # define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
6318 # define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
6322 linux_process_target::supports_read_loadmap ()
6328 linux_process_target::read_loadmap (const char *annex
, CORE_ADDR offset
,
6329 unsigned char *myaddr
, unsigned int len
)
6331 int pid
= lwpid_of (current_thread
);
6333 struct target_loadmap
*data
= NULL
;
6334 unsigned int actual_length
, copy_length
;
6336 if (strcmp (annex
, "exec") == 0)
6337 addr
= (int) LINUX_LOADMAP_EXEC
;
6338 else if (strcmp (annex
, "interp") == 0)
6339 addr
= (int) LINUX_LOADMAP_INTERP
;
6343 if (ptrace (LINUX_LOADMAP
, pid
, addr
, &data
) != 0)
6349 actual_length
= sizeof (struct target_loadmap
)
6350 + sizeof (struct target_loadseg
) * data
->nsegs
;
6352 if (offset
< 0 || offset
> actual_length
)
6355 copy_length
= actual_length
- offset
< len
? actual_length
- offset
: len
;
6356 memcpy (myaddr
, (char *) data
+ offset
, copy_length
);
6359 #endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
6362 linux_process_target::supports_catch_syscall ()
6364 return (low_supports_catch_syscall ()
6365 && linux_supports_tracesysgood ());
6369 linux_process_target::low_supports_catch_syscall ()
6375 linux_process_target::read_pc (regcache
*regcache
)
6377 if (!low_supports_breakpoints ())
6380 return low_get_pc (regcache
);
6384 linux_process_target::write_pc (regcache
*regcache
, CORE_ADDR pc
)
6386 gdb_assert (low_supports_breakpoints ());
6388 low_set_pc (regcache
, pc
);
6392 linux_process_target::supports_thread_stopped ()
6398 linux_process_target::thread_stopped (thread_info
*thread
)
6400 return get_thread_lwp (thread
)->stopped
;
6403 /* This exposes stop-all-threads functionality to other modules. */
6406 linux_process_target::pause_all (bool freeze
)
6408 stop_all_lwps (freeze
, NULL
);
6411 /* This exposes unstop-all-threads functionality to other gdbserver
6415 linux_process_target::unpause_all (bool unfreeze
)
6417 unstop_all_lwps (unfreeze
, NULL
);
6421 linux_process_target::prepare_to_access_memory ()
6423 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6426 target_pause_all (true);
6431 linux_process_target::done_accessing_memory ()
6433 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6436 target_unpause_all (true);
6439 /* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
6442 get_phdr_phnum_from_proc_auxv (const int pid
, const int is_elf64
,
6443 CORE_ADDR
*phdr_memaddr
, int *num_phdr
)
6445 char filename
[PATH_MAX
];
6447 const int auxv_size
= is_elf64
6448 ? sizeof (Elf64_auxv_t
) : sizeof (Elf32_auxv_t
);
6449 char buf
[sizeof (Elf64_auxv_t
)]; /* The larger of the two. */
6451 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
6453 fd
= open (filename
, O_RDONLY
);
6459 while (read (fd
, buf
, auxv_size
) == auxv_size
6460 && (*phdr_memaddr
== 0 || *num_phdr
== 0))
6464 Elf64_auxv_t
*const aux
= (Elf64_auxv_t
*) buf
;
6466 switch (aux
->a_type
)
6469 *phdr_memaddr
= aux
->a_un
.a_val
;
6472 *num_phdr
= aux
->a_un
.a_val
;
6478 Elf32_auxv_t
*const aux
= (Elf32_auxv_t
*) buf
;
6480 switch (aux
->a_type
)
6483 *phdr_memaddr
= aux
->a_un
.a_val
;
6486 *num_phdr
= aux
->a_un
.a_val
;
6494 if (*phdr_memaddr
== 0 || *num_phdr
== 0)
6496 warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
6497 "phdr_memaddr = %ld, phdr_num = %d",
6498 (long) *phdr_memaddr
, *num_phdr
);
6505 /* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
6508 get_dynamic (const int pid
, const int is_elf64
)
6510 CORE_ADDR phdr_memaddr
, relocation
;
6512 unsigned char *phdr_buf
;
6513 const int phdr_size
= is_elf64
? sizeof (Elf64_Phdr
) : sizeof (Elf32_Phdr
);
6515 if (get_phdr_phnum_from_proc_auxv (pid
, is_elf64
, &phdr_memaddr
, &num_phdr
))
6518 gdb_assert (num_phdr
< 100); /* Basic sanity check. */
6519 phdr_buf
= (unsigned char *) alloca (num_phdr
* phdr_size
);
6521 if (linux_read_memory (phdr_memaddr
, phdr_buf
, num_phdr
* phdr_size
))
6524 /* Compute relocation: it is expected to be 0 for "regular" executables,
6525 non-zero for PIE ones. */
6527 for (i
= 0; relocation
== -1 && i
< num_phdr
; i
++)
6530 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6532 if (p
->p_type
== PT_PHDR
)
6533 relocation
= phdr_memaddr
- p
->p_vaddr
;
6537 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6539 if (p
->p_type
== PT_PHDR
)
6540 relocation
= phdr_memaddr
- p
->p_vaddr
;
6543 if (relocation
== -1)
6545 /* PT_PHDR is optional, but necessary for PIE in general. Fortunately
6546 any real world executables, including PIE executables, have always
6547 PT_PHDR present. PT_PHDR is not present in some shared libraries or
6548 in fpc (Free Pascal 2.4) binaries but neither of those have a need for
6549 or present DT_DEBUG anyway (fpc binaries are statically linked).
6551 Therefore if there exists DT_DEBUG there is always also PT_PHDR.
6553 GDB could find RELOCATION also from AT_ENTRY - e_entry. */
6558 for (i
= 0; i
< num_phdr
; i
++)
6562 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6564 if (p
->p_type
== PT_DYNAMIC
)
6565 return p
->p_vaddr
+ relocation
;
6569 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6571 if (p
->p_type
== PT_DYNAMIC
)
6572 return p
->p_vaddr
+ relocation
;
6579 /* Return &_r_debug in the inferior, or -1 if not present. Return value
6580 can be 0 if the inferior does not yet have the library list initialized.
6581 We look for DT_MIPS_RLD_MAP first. MIPS executables use this instead of
6582 DT_DEBUG, although they sometimes contain an unused DT_DEBUG entry too. */
6585 get_r_debug (const int pid
, const int is_elf64
)
6587 CORE_ADDR dynamic_memaddr
;
6588 const int dyn_size
= is_elf64
? sizeof (Elf64_Dyn
) : sizeof (Elf32_Dyn
);
6589 unsigned char buf
[sizeof (Elf64_Dyn
)]; /* The larger of the two. */
6592 dynamic_memaddr
= get_dynamic (pid
, is_elf64
);
6593 if (dynamic_memaddr
== 0)
6596 while (linux_read_memory (dynamic_memaddr
, buf
, dyn_size
) == 0)
6600 Elf64_Dyn
*const dyn
= (Elf64_Dyn
*) buf
;
6601 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
6605 unsigned char buf
[sizeof (Elf64_Xword
)];
6609 #ifdef DT_MIPS_RLD_MAP
6610 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
6612 if (linux_read_memory (dyn
->d_un
.d_val
,
6613 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6618 #endif /* DT_MIPS_RLD_MAP */
6619 #ifdef DT_MIPS_RLD_MAP_REL
6620 if (dyn
->d_tag
== DT_MIPS_RLD_MAP_REL
)
6622 if (linux_read_memory (dyn
->d_un
.d_val
+ dynamic_memaddr
,
6623 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6628 #endif /* DT_MIPS_RLD_MAP_REL */
6630 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
6631 map
= dyn
->d_un
.d_val
;
6633 if (dyn
->d_tag
== DT_NULL
)
6638 Elf32_Dyn
*const dyn
= (Elf32_Dyn
*) buf
;
6639 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
6643 unsigned char buf
[sizeof (Elf32_Word
)];
6647 #ifdef DT_MIPS_RLD_MAP
6648 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
6650 if (linux_read_memory (dyn
->d_un
.d_val
,
6651 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6656 #endif /* DT_MIPS_RLD_MAP */
6657 #ifdef DT_MIPS_RLD_MAP_REL
6658 if (dyn
->d_tag
== DT_MIPS_RLD_MAP_REL
)
6660 if (linux_read_memory (dyn
->d_un
.d_val
+ dynamic_memaddr
,
6661 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6666 #endif /* DT_MIPS_RLD_MAP_REL */
6668 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
6669 map
= dyn
->d_un
.d_val
;
6671 if (dyn
->d_tag
== DT_NULL
)
6675 dynamic_memaddr
+= dyn_size
;
6681 /* Read one pointer from MEMADDR in the inferior. */
6684 read_one_ptr (CORE_ADDR memaddr
, CORE_ADDR
*ptr
, int ptr_size
)
6688 /* Go through a union so this works on either big or little endian
6689 hosts, when the inferior's pointer size is smaller than the size
6690 of CORE_ADDR. It is assumed the inferior's endianness is the
6691 same of the superior's. */
6694 CORE_ADDR core_addr
;
6699 ret
= linux_read_memory (memaddr
, &addr
.uc
, ptr_size
);
6702 if (ptr_size
== sizeof (CORE_ADDR
))
6703 *ptr
= addr
.core_addr
;
6704 else if (ptr_size
== sizeof (unsigned int))
6707 gdb_assert_not_reached ("unhandled pointer size");
6713 linux_process_target::supports_qxfer_libraries_svr4 ()
6718 struct link_map_offsets
6720 /* Offset and size of r_debug.r_version. */
6721 int r_version_offset
;
6723 /* Offset and size of r_debug.r_map. */
6726 /* Offset to l_addr field in struct link_map. */
6729 /* Offset to l_name field in struct link_map. */
6732 /* Offset to l_ld field in struct link_map. */
6735 /* Offset to l_next field in struct link_map. */
6738 /* Offset to l_prev field in struct link_map. */
6742 /* Construct qXfer:libraries-svr4:read reply. */
6745 linux_process_target::qxfer_libraries_svr4 (const char *annex
,
6746 unsigned char *readbuf
,
6747 unsigned const char *writebuf
,
6748 CORE_ADDR offset
, int len
)
6750 struct process_info_private
*const priv
= current_process ()->priv
;
6751 char filename
[PATH_MAX
];
6754 static const struct link_map_offsets lmo_32bit_offsets
=
6756 0, /* r_version offset. */
6757 4, /* r_debug.r_map offset. */
6758 0, /* l_addr offset in link_map. */
6759 4, /* l_name offset in link_map. */
6760 8, /* l_ld offset in link_map. */
6761 12, /* l_next offset in link_map. */
6762 16 /* l_prev offset in link_map. */
6765 static const struct link_map_offsets lmo_64bit_offsets
=
6767 0, /* r_version offset. */
6768 8, /* r_debug.r_map offset. */
6769 0, /* l_addr offset in link_map. */
6770 8, /* l_name offset in link_map. */
6771 16, /* l_ld offset in link_map. */
6772 24, /* l_next offset in link_map. */
6773 32 /* l_prev offset in link_map. */
6775 const struct link_map_offsets
*lmo
;
6776 unsigned int machine
;
6778 CORE_ADDR lm_addr
= 0, lm_prev
= 0;
6779 CORE_ADDR l_name
, l_addr
, l_ld
, l_next
, l_prev
;
6780 int header_done
= 0;
6782 if (writebuf
!= NULL
)
6784 if (readbuf
== NULL
)
6787 pid
= lwpid_of (current_thread
);
6788 xsnprintf (filename
, sizeof filename
, "/proc/%d/exe", pid
);
6789 is_elf64
= elf_64_file_p (filename
, &machine
);
6790 lmo
= is_elf64
? &lmo_64bit_offsets
: &lmo_32bit_offsets
;
6791 ptr_size
= is_elf64
? 8 : 4;
6793 while (annex
[0] != '\0')
6799 sep
= strchr (annex
, '=');
6803 name_len
= sep
- annex
;
6804 if (name_len
== 5 && startswith (annex
, "start"))
6806 else if (name_len
== 4 && startswith (annex
, "prev"))
6810 annex
= strchr (sep
, ';');
6817 annex
= decode_address_to_semicolon (addrp
, sep
+ 1);
6824 if (priv
->r_debug
== 0)
6825 priv
->r_debug
= get_r_debug (pid
, is_elf64
);
6827 /* We failed to find DT_DEBUG. Such situation will not change
6828 for this inferior - do not retry it. Report it to GDB as
6829 E01, see for the reasons at the GDB solib-svr4.c side. */
6830 if (priv
->r_debug
== (CORE_ADDR
) -1)
6833 if (priv
->r_debug
!= 0)
6835 if (linux_read_memory (priv
->r_debug
+ lmo
->r_version_offset
,
6836 (unsigned char *) &r_version
,
6837 sizeof (r_version
)) != 0
6840 warning ("unexpected r_debug version %d", r_version
);
6842 else if (read_one_ptr (priv
->r_debug
+ lmo
->r_map_offset
,
6843 &lm_addr
, ptr_size
) != 0)
6845 warning ("unable to read r_map from 0x%lx",
6846 (long) priv
->r_debug
+ lmo
->r_map_offset
);
6851 std::string document
= "<library-list-svr4 version=\"1.0\"";
6854 && read_one_ptr (lm_addr
+ lmo
->l_name_offset
,
6855 &l_name
, ptr_size
) == 0
6856 && read_one_ptr (lm_addr
+ lmo
->l_addr_offset
,
6857 &l_addr
, ptr_size
) == 0
6858 && read_one_ptr (lm_addr
+ lmo
->l_ld_offset
,
6859 &l_ld
, ptr_size
) == 0
6860 && read_one_ptr (lm_addr
+ lmo
->l_prev_offset
,
6861 &l_prev
, ptr_size
) == 0
6862 && read_one_ptr (lm_addr
+ lmo
->l_next_offset
,
6863 &l_next
, ptr_size
) == 0)
6865 unsigned char libname
[PATH_MAX
];
6867 if (lm_prev
!= l_prev
)
6869 warning ("Corrupted shared library list: 0x%lx != 0x%lx",
6870 (long) lm_prev
, (long) l_prev
);
6874 /* Ignore the first entry even if it has valid name as the first entry
6875 corresponds to the main executable. The first entry should not be
6876 skipped if the dynamic loader was loaded late by a static executable
6877 (see solib-svr4.c parameter ignore_first). But in such case the main
6878 executable does not have PT_DYNAMIC present and this function already
6879 exited above due to failed get_r_debug. */
6881 string_appendf (document
, " main-lm=\"0x%lx\"", (unsigned long) lm_addr
);
6884 /* Not checking for error because reading may stop before
6885 we've got PATH_MAX worth of characters. */
6887 linux_read_memory (l_name
, libname
, sizeof (libname
) - 1);
6888 libname
[sizeof (libname
) - 1] = '\0';
6889 if (libname
[0] != '\0')
6893 /* Terminate `<library-list-svr4'. */
6898 string_appendf (document
, "<library name=\"");
6899 xml_escape_text_append (&document
, (char *) libname
);
6900 string_appendf (document
, "\" lm=\"0x%lx\" "
6901 "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
6902 (unsigned long) lm_addr
, (unsigned long) l_addr
,
6903 (unsigned long) l_ld
);
6913 /* Empty list; terminate `<library-list-svr4'. */
6917 document
+= "</library-list-svr4>";
6919 int document_len
= document
.length ();
6920 if (offset
< document_len
)
6921 document_len
-= offset
;
6924 if (len
> document_len
)
6927 memcpy (readbuf
, document
.data () + offset
, len
);
6932 #ifdef HAVE_LINUX_BTRACE
6934 btrace_target_info
*
6935 linux_process_target::enable_btrace (ptid_t ptid
,
6936 const btrace_config
*conf
)
6938 return linux_enable_btrace (ptid
, conf
);
6941 /* See to_disable_btrace target method. */
6944 linux_process_target::disable_btrace (btrace_target_info
*tinfo
)
6946 enum btrace_error err
;
6948 err
= linux_disable_btrace (tinfo
);
6949 return (err
== BTRACE_ERR_NONE
? 0 : -1);
6952 /* Encode an Intel Processor Trace configuration. */
6955 linux_low_encode_pt_config (struct buffer
*buffer
,
6956 const struct btrace_data_pt_config
*config
)
6958 buffer_grow_str (buffer
, "<pt-config>\n");
6960 switch (config
->cpu
.vendor
)
6963 buffer_xml_printf (buffer
, "<cpu vendor=\"GenuineIntel\" family=\"%u\" "
6964 "model=\"%u\" stepping=\"%u\"/>\n",
6965 config
->cpu
.family
, config
->cpu
.model
,
6966 config
->cpu
.stepping
);
6973 buffer_grow_str (buffer
, "</pt-config>\n");
6976 /* Encode a raw buffer. */
6979 linux_low_encode_raw (struct buffer
*buffer
, const gdb_byte
*data
,
6985 /* We use hex encoding - see gdbsupport/rsp-low.h. */
6986 buffer_grow_str (buffer
, "<raw>\n");
6992 elem
[0] = tohex ((*data
>> 4) & 0xf);
6993 elem
[1] = tohex (*data
++ & 0xf);
6995 buffer_grow (buffer
, elem
, 2);
6998 buffer_grow_str (buffer
, "</raw>\n");
7001 /* See to_read_btrace target method. */
7004 linux_process_target::read_btrace (btrace_target_info
*tinfo
,
7006 enum btrace_read_type type
)
7008 struct btrace_data btrace
;
7009 enum btrace_error err
;
7011 err
= linux_read_btrace (&btrace
, tinfo
, type
);
7012 if (err
!= BTRACE_ERR_NONE
)
7014 if (err
== BTRACE_ERR_OVERFLOW
)
7015 buffer_grow_str0 (buffer
, "E.Overflow.");
7017 buffer_grow_str0 (buffer
, "E.Generic Error.");
7022 switch (btrace
.format
)
7024 case BTRACE_FORMAT_NONE
:
7025 buffer_grow_str0 (buffer
, "E.No Trace.");
7028 case BTRACE_FORMAT_BTS
:
7029 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
7030 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
7032 for (const btrace_block
&block
: *btrace
.variant
.bts
.blocks
)
7033 buffer_xml_printf (buffer
, "<block begin=\"0x%s\" end=\"0x%s\"/>\n",
7034 paddress (block
.begin
), paddress (block
.end
));
7036 buffer_grow_str0 (buffer
, "</btrace>\n");
7039 case BTRACE_FORMAT_PT
:
7040 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
7041 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
7042 buffer_grow_str (buffer
, "<pt>\n");
7044 linux_low_encode_pt_config (buffer
, &btrace
.variant
.pt
.config
);
7046 linux_low_encode_raw (buffer
, btrace
.variant
.pt
.data
,
7047 btrace
.variant
.pt
.size
);
7049 buffer_grow_str (buffer
, "</pt>\n");
7050 buffer_grow_str0 (buffer
, "</btrace>\n");
7054 buffer_grow_str0 (buffer
, "E.Unsupported Trace Format.");
7061 /* See to_btrace_conf target method. */
7064 linux_process_target::read_btrace_conf (const btrace_target_info
*tinfo
,
7067 const struct btrace_config
*conf
;
7069 buffer_grow_str (buffer
, "<!DOCTYPE btrace-conf SYSTEM \"btrace-conf.dtd\">\n");
7070 buffer_grow_str (buffer
, "<btrace-conf version=\"1.0\">\n");
7072 conf
= linux_btrace_conf (tinfo
);
7075 switch (conf
->format
)
7077 case BTRACE_FORMAT_NONE
:
7080 case BTRACE_FORMAT_BTS
:
7081 buffer_xml_printf (buffer
, "<bts");
7082 buffer_xml_printf (buffer
, " size=\"0x%x\"", conf
->bts
.size
);
7083 buffer_xml_printf (buffer
, " />\n");
7086 case BTRACE_FORMAT_PT
:
7087 buffer_xml_printf (buffer
, "<pt");
7088 buffer_xml_printf (buffer
, " size=\"0x%x\"", conf
->pt
.size
);
7089 buffer_xml_printf (buffer
, "/>\n");
7094 buffer_grow_str0 (buffer
, "</btrace-conf>\n");
7097 #endif /* HAVE_LINUX_BTRACE */
7099 /* See nat/linux-nat.h. */
7102 current_lwp_ptid (void)
7104 return ptid_of (current_thread
);
7108 linux_process_target::thread_name (ptid_t thread
)
7110 return linux_proc_tid_get_name (thread
);
7115 linux_process_target::thread_handle (ptid_t ptid
, gdb_byte
**handle
,
7118 return thread_db_thread_handle (ptid
, handle
, handle_len
);
7123 linux_process_target::thread_pending_parent (thread_info
*thread
)
7125 lwp_info
*parent
= get_thread_lwp (thread
)->pending_parent ();
7127 if (parent
== nullptr)
7130 return get_lwp_thread (parent
);
7133 /* Default implementation of linux_target_ops method "set_pc" for
7134 32-bit pc register which is literally named "pc". */
7137 linux_set_pc_32bit (struct regcache
*regcache
, CORE_ADDR pc
)
7139 uint32_t newpc
= pc
;
7141 supply_register_by_name (regcache
, "pc", &newpc
);
7144 /* Default implementation of linux_target_ops method "get_pc" for
7145 32-bit pc register which is literally named "pc". */
7148 linux_get_pc_32bit (struct regcache
*regcache
)
7152 collect_register_by_name (regcache
, "pc", &pc
);
7154 debug_printf ("stop pc is 0x%" PRIx32
"\n", pc
);
7158 /* Default implementation of linux_target_ops method "set_pc" for
7159 64-bit pc register which is literally named "pc". */
7162 linux_set_pc_64bit (struct regcache
*regcache
, CORE_ADDR pc
)
7164 uint64_t newpc
= pc
;
7166 supply_register_by_name (regcache
, "pc", &newpc
);
7169 /* Default implementation of linux_target_ops method "get_pc" for
7170 64-bit pc register which is literally named "pc". */
7173 linux_get_pc_64bit (struct regcache
*regcache
)
7177 collect_register_by_name (regcache
, "pc", &pc
);
7179 debug_printf ("stop pc is 0x%" PRIx64
"\n", pc
);
7183 /* See linux-low.h. */
7186 linux_get_auxv (int wordsize
, CORE_ADDR match
, CORE_ADDR
*valp
)
7188 gdb_byte
*data
= (gdb_byte
*) alloca (2 * wordsize
);
7191 gdb_assert (wordsize
== 4 || wordsize
== 8);
7193 while (the_target
->read_auxv (offset
, data
, 2 * wordsize
) == 2 * wordsize
)
7197 uint32_t *data_p
= (uint32_t *) data
;
7198 if (data_p
[0] == match
)
7206 uint64_t *data_p
= (uint64_t *) data
;
7207 if (data_p
[0] == match
)
7214 offset
+= 2 * wordsize
;
7220 /* See linux-low.h. */
7223 linux_get_hwcap (int wordsize
)
7225 CORE_ADDR hwcap
= 0;
7226 linux_get_auxv (wordsize
, AT_HWCAP
, &hwcap
);
7230 /* See linux-low.h. */
7233 linux_get_hwcap2 (int wordsize
)
7235 CORE_ADDR hwcap2
= 0;
7236 linux_get_auxv (wordsize
, AT_HWCAP2
, &hwcap2
);
7240 #ifdef HAVE_LINUX_REGSETS
7242 initialize_regsets_info (struct regsets_info
*info
)
7244 for (info
->num_regsets
= 0;
7245 info
->regsets
[info
->num_regsets
].size
>= 0;
7246 info
->num_regsets
++)
7252 initialize_low (void)
7254 struct sigaction sigchld_action
;
7256 memset (&sigchld_action
, 0, sizeof (sigchld_action
));
7257 set_target_ops (the_linux_target
);
7259 linux_ptrace_init_warnings ();
7260 linux_proc_init_warnings ();
7262 sigchld_action
.sa_handler
= sigchld_handler
;
7263 sigemptyset (&sigchld_action
.sa_mask
);
7264 sigchld_action
.sa_flags
= SA_RESTART
;
7265 sigaction (SIGCHLD
, &sigchld_action
, NULL
);
7267 initialize_low_arch ();
7269 linux_check_ptrace_features ();