1 /* Low level interface to ptrace, for the remote server for GDB.
2 Copyright (C) 1995-2016 Free Software Foundation, Inc.
4 This file is part of GDB.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>. */
20 #include "linux-low.h"
21 #include "nat/linux-osdata.h"
26 #include "nat/linux-nat.h"
27 #include "nat/linux-waitpid.h"
29 #include "nat/gdb_ptrace.h"
30 #include "nat/linux-ptrace.h"
31 #include "nat/linux-procfs.h"
32 #include "nat/linux-personality.h"
34 #include <sys/ioctl.h>
37 #include <sys/syscall.h>
41 #include <sys/types.h>
46 #include "filestuff.h"
47 #include "tracepoint.h"
50 /* Don't include <linux/elf.h> here. If it got included by gdb_proc_service.h
51 then ELFMAG0 will have been defined. If it didn't get included by
52 gdb_proc_service.h then including it will likely introduce a duplicate
53 definition of elf_fpregset_t. */
56 #include "nat/linux-namespaces.h"
59 #define SPUFS_MAGIC 0x23c9b64e
62 #ifdef HAVE_PERSONALITY
63 # include <sys/personality.h>
64 # if !HAVE_DECL_ADDR_NO_RANDOMIZE
65 # define ADDR_NO_RANDOMIZE 0x0040000
73 /* Some targets did not define these ptrace constants from the start,
74 so gdbserver defines them locally here. In the future, these may
75 be removed after they are added to asm/ptrace.h. */
76 #if !(defined(PT_TEXT_ADDR) \
77 || defined(PT_DATA_ADDR) \
78 || defined(PT_TEXT_END_ADDR))
79 #if defined(__mcoldfire__)
80 /* These are still undefined in 3.10 kernels. */
81 #define PT_TEXT_ADDR 49*4
82 #define PT_DATA_ADDR 50*4
83 #define PT_TEXT_END_ADDR 51*4
84 /* BFIN already defines these since at least 2.6.32 kernels. */
86 #define PT_TEXT_ADDR 220
87 #define PT_TEXT_END_ADDR 224
88 #define PT_DATA_ADDR 228
89 /* These are still undefined in 3.10 kernels. */
90 #elif defined(__TMS320C6X__)
91 #define PT_TEXT_ADDR (0x10000*4)
92 #define PT_DATA_ADDR (0x10004*4)
93 #define PT_TEXT_END_ADDR (0x10008*4)
97 #ifdef HAVE_LINUX_BTRACE
98 # include "nat/linux-btrace.h"
99 # include "btrace-common.h"
102 #ifndef HAVE_ELF32_AUXV_T
103 /* Copied from glibc's elf.h. */
106 uint32_t a_type
; /* Entry type */
109 uint32_t a_val
; /* Integer value */
110 /* We use to have pointer elements added here. We cannot do that,
111 though, since it does not work when using 32-bit definitions
112 on 64-bit platforms and vice versa. */
117 #ifndef HAVE_ELF64_AUXV_T
118 /* Copied from glibc's elf.h. */
121 uint64_t a_type
; /* Entry type */
124 uint64_t a_val
; /* Integer value */
125 /* We use to have pointer elements added here. We cannot do that,
126 though, since it does not work when using 32-bit definitions
127 on 64-bit platforms and vice versa. */
132 /* Does the current host support PTRACE_GETREGSET? */
133 int have_ptrace_getregset
= -1;
137 /* See nat/linux-nat.h. */
140 ptid_of_lwp (struct lwp_info
*lwp
)
142 return ptid_of (get_lwp_thread (lwp
));
145 /* See nat/linux-nat.h. */
148 lwp_set_arch_private_info (struct lwp_info
*lwp
,
149 struct arch_lwp_info
*info
)
151 lwp
->arch_private
= info
;
154 /* See nat/linux-nat.h. */
156 struct arch_lwp_info
*
157 lwp_arch_private_info (struct lwp_info
*lwp
)
159 return lwp
->arch_private
;
162 /* See nat/linux-nat.h. */
165 lwp_is_stopped (struct lwp_info
*lwp
)
170 /* See nat/linux-nat.h. */
172 enum target_stop_reason
173 lwp_stop_reason (struct lwp_info
*lwp
)
175 return lwp
->stop_reason
;
178 /* A list of all unknown processes which receive stop signals. Some
179 other process will presumably claim each of these as forked
180 children momentarily. */
182 struct simple_pid_list
184 /* The process ID. */
187 /* The status as reported by waitpid. */
191 struct simple_pid_list
*next
;
193 struct simple_pid_list
*stopped_pids
;
195 /* Trivial list manipulation functions to keep track of a list of new
196 stopped processes. */
199 add_to_pid_list (struct simple_pid_list
**listp
, int pid
, int status
)
201 struct simple_pid_list
*new_pid
= XNEW (struct simple_pid_list
);
204 new_pid
->status
= status
;
205 new_pid
->next
= *listp
;
210 pull_pid_from_list (struct simple_pid_list
**listp
, int pid
, int *statusp
)
212 struct simple_pid_list
**p
;
214 for (p
= listp
; *p
!= NULL
; p
= &(*p
)->next
)
215 if ((*p
)->pid
== pid
)
217 struct simple_pid_list
*next
= (*p
)->next
;
219 *statusp
= (*p
)->status
;
227 enum stopping_threads_kind
229 /* Not stopping threads presently. */
230 NOT_STOPPING_THREADS
,
232 /* Stopping threads. */
235 /* Stopping and suspending threads. */
236 STOPPING_AND_SUSPENDING_THREADS
239 /* This is set while stop_all_lwps is in effect. */
240 enum stopping_threads_kind stopping_threads
= NOT_STOPPING_THREADS
;
242 /* FIXME make into a target method? */
243 int using_threads
= 1;
245 /* True if we're presently stabilizing threads (moving them out of
247 static int stabilizing_threads
;
249 static void linux_resume_one_lwp (struct lwp_info
*lwp
,
250 int step
, int signal
, siginfo_t
*info
);
251 static void linux_resume (struct thread_resume
*resume_info
, size_t n
);
252 static void stop_all_lwps (int suspend
, struct lwp_info
*except
);
253 static void unstop_all_lwps (int unsuspend
, struct lwp_info
*except
);
254 static int linux_wait_for_event_filtered (ptid_t wait_ptid
, ptid_t filter_ptid
,
255 int *wstat
, int options
);
256 static int linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
);
257 static struct lwp_info
*add_lwp (ptid_t ptid
);
258 static void linux_mourn (struct process_info
*process
);
259 static int linux_stopped_by_watchpoint (void);
260 static void mark_lwp_dead (struct lwp_info
*lwp
, int wstat
);
261 static int lwp_is_marked_dead (struct lwp_info
*lwp
);
262 static void proceed_all_lwps (void);
263 static int finish_step_over (struct lwp_info
*lwp
);
264 static int kill_lwp (unsigned long lwpid
, int signo
);
265 static void enqueue_pending_signal (struct lwp_info
*lwp
, int signal
, siginfo_t
*info
);
266 static void complete_ongoing_step_over (void);
267 static int linux_low_ptrace_options (int attached
);
269 /* When the event-loop is doing a step-over, this points at the thread
271 ptid_t step_over_bkpt
;
273 /* True if the low target can hardware single-step. */
276 can_hardware_single_step (void)
278 if (the_low_target
.supports_hardware_single_step
!= NULL
)
279 return the_low_target
.supports_hardware_single_step ();
284 /* True if the low target can software single-step. Such targets
285 implement the GET_NEXT_PCS callback. */
288 can_software_single_step (void)
290 return (the_low_target
.get_next_pcs
!= NULL
);
293 /* True if the low target supports memory breakpoints. If so, we'll
294 have a GET_PC implementation. */
297 supports_breakpoints (void)
299 return (the_low_target
.get_pc
!= NULL
);
302 /* Returns true if this target can support fast tracepoints. This
303 does not mean that the in-process agent has been loaded in the
307 supports_fast_tracepoints (void)
309 return the_low_target
.install_fast_tracepoint_jump_pad
!= NULL
;
312 /* True if LWP is stopped in its stepping range. */
315 lwp_in_step_range (struct lwp_info
*lwp
)
317 CORE_ADDR pc
= lwp
->stop_pc
;
319 return (pc
>= lwp
->step_range_start
&& pc
< lwp
->step_range_end
);
322 struct pending_signals
326 struct pending_signals
*prev
;
329 /* The read/write ends of the pipe registered as waitable file in the
331 static int linux_event_pipe
[2] = { -1, -1 };
333 /* True if we're currently in async mode. */
334 #define target_is_async_p() (linux_event_pipe[0] != -1)
336 static void send_sigstop (struct lwp_info
*lwp
);
337 static void wait_for_sigstop (void);
339 /* Return non-zero if HEADER is a 64-bit ELF file. */
342 elf_64_header_p (const Elf64_Ehdr
*header
, unsigned int *machine
)
344 if (header
->e_ident
[EI_MAG0
] == ELFMAG0
345 && header
->e_ident
[EI_MAG1
] == ELFMAG1
346 && header
->e_ident
[EI_MAG2
] == ELFMAG2
347 && header
->e_ident
[EI_MAG3
] == ELFMAG3
)
349 *machine
= header
->e_machine
;
350 return header
->e_ident
[EI_CLASS
] == ELFCLASS64
;
357 /* Return non-zero if FILE is a 64-bit ELF file,
358 zero if the file is not a 64-bit ELF file,
359 and -1 if the file is not accessible or doesn't exist. */
362 elf_64_file_p (const char *file
, unsigned int *machine
)
367 fd
= open (file
, O_RDONLY
);
371 if (read (fd
, &header
, sizeof (header
)) != sizeof (header
))
378 return elf_64_header_p (&header
, machine
);
381 /* Accepts an integer PID; Returns true if the executable PID is
382 running is a 64-bit ELF file.. */
385 linux_pid_exe_is_elf_64_file (int pid
, unsigned int *machine
)
389 sprintf (file
, "/proc/%d/exe", pid
);
390 return elf_64_file_p (file
, machine
);
394 delete_lwp (struct lwp_info
*lwp
)
396 struct thread_info
*thr
= get_lwp_thread (lwp
);
399 debug_printf ("deleting %ld\n", lwpid_of (thr
));
402 free (lwp
->arch_private
);
406 /* Add a process to the common process list, and set its private
409 static struct process_info
*
410 linux_add_process (int pid
, int attached
)
412 struct process_info
*proc
;
414 proc
= add_process (pid
, attached
);
415 proc
->priv
= XCNEW (struct process_info_private
);
417 if (the_low_target
.new_process
!= NULL
)
418 proc
->priv
->arch_private
= the_low_target
.new_process ();
423 static CORE_ADDR
get_pc (struct lwp_info
*lwp
);
425 /* Call the target arch_setup function on the current thread. */
428 linux_arch_setup (void)
430 the_low_target
.arch_setup ();
433 /* Call the target arch_setup function on THREAD. */
436 linux_arch_setup_thread (struct thread_info
*thread
)
438 struct thread_info
*saved_thread
;
440 saved_thread
= current_thread
;
441 current_thread
= thread
;
445 current_thread
= saved_thread
;
448 /* Handle a GNU/Linux extended wait response. If we see a clone,
449 fork, or vfork event, we need to add the new LWP to our list
450 (and return 0 so as not to report the trap to higher layers).
451 If we see an exec event, we will modify ORIG_EVENT_LWP to point
452 to a new LWP representing the new program. */
455 handle_extended_wait (struct lwp_info
**orig_event_lwp
, int wstat
)
457 struct lwp_info
*event_lwp
= *orig_event_lwp
;
458 int event
= linux_ptrace_get_extended_event (wstat
);
459 struct thread_info
*event_thr
= get_lwp_thread (event_lwp
);
460 struct lwp_info
*new_lwp
;
462 gdb_assert (event_lwp
->waitstatus
.kind
== TARGET_WAITKIND_IGNORE
);
464 if ((event
== PTRACE_EVENT_FORK
) || (event
== PTRACE_EVENT_VFORK
)
465 || (event
== PTRACE_EVENT_CLONE
))
468 unsigned long new_pid
;
471 /* Get the pid of the new lwp. */
472 ptrace (PTRACE_GETEVENTMSG
, lwpid_of (event_thr
), (PTRACE_TYPE_ARG3
) 0,
475 /* If we haven't already seen the new PID stop, wait for it now. */
476 if (!pull_pid_from_list (&stopped_pids
, new_pid
, &status
))
478 /* The new child has a pending SIGSTOP. We can't affect it until it
479 hits the SIGSTOP, but we're already attached. */
481 ret
= my_waitpid (new_pid
, &status
, __WALL
);
484 perror_with_name ("waiting for new child");
485 else if (ret
!= new_pid
)
486 warning ("wait returned unexpected PID %d", ret
);
487 else if (!WIFSTOPPED (status
))
488 warning ("wait returned unexpected status 0x%x", status
);
491 if (event
== PTRACE_EVENT_FORK
|| event
== PTRACE_EVENT_VFORK
)
493 struct process_info
*parent_proc
;
494 struct process_info
*child_proc
;
495 struct lwp_info
*child_lwp
;
496 struct thread_info
*child_thr
;
497 struct target_desc
*tdesc
;
499 ptid
= ptid_build (new_pid
, new_pid
, 0);
503 debug_printf ("HEW: Got fork event from LWP %ld, "
505 ptid_get_lwp (ptid_of (event_thr
)),
506 ptid_get_pid (ptid
));
509 /* Add the new process to the tables and clone the breakpoint
510 lists of the parent. We need to do this even if the new process
511 will be detached, since we will need the process object and the
512 breakpoints to remove any breakpoints from memory when we
513 detach, and the client side will access registers. */
514 child_proc
= linux_add_process (new_pid
, 0);
515 gdb_assert (child_proc
!= NULL
);
516 child_lwp
= add_lwp (ptid
);
517 gdb_assert (child_lwp
!= NULL
);
518 child_lwp
->stopped
= 1;
519 child_lwp
->must_set_ptrace_flags
= 1;
520 child_lwp
->status_pending_p
= 0;
521 child_thr
= get_lwp_thread (child_lwp
);
522 child_thr
->last_resume_kind
= resume_stop
;
523 child_thr
->last_status
.kind
= TARGET_WAITKIND_STOPPED
;
525 /* If we're suspending all threads, leave this one suspended
527 if (stopping_threads
== STOPPING_AND_SUSPENDING_THREADS
)
530 debug_printf ("HEW: leaving child suspended\n");
531 child_lwp
->suspended
= 1;
534 parent_proc
= get_thread_process (event_thr
);
535 child_proc
->attached
= parent_proc
->attached
;
536 clone_all_breakpoints (&child_proc
->breakpoints
,
537 &child_proc
->raw_breakpoints
,
538 parent_proc
->breakpoints
);
540 tdesc
= XNEW (struct target_desc
);
541 copy_target_description (tdesc
, parent_proc
->tdesc
);
542 child_proc
->tdesc
= tdesc
;
544 /* Clone arch-specific process data. */
545 if (the_low_target
.new_fork
!= NULL
)
546 the_low_target
.new_fork (parent_proc
, child_proc
);
548 /* Save fork info in the parent thread. */
549 if (event
== PTRACE_EVENT_FORK
)
550 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_FORKED
;
551 else if (event
== PTRACE_EVENT_VFORK
)
552 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_VFORKED
;
554 event_lwp
->waitstatus
.value
.related_pid
= ptid
;
556 /* The status_pending field contains bits denoting the
557 extended event, so when the pending event is handled,
558 the handler will look at lwp->waitstatus. */
559 event_lwp
->status_pending_p
= 1;
560 event_lwp
->status_pending
= wstat
;
562 /* Report the event. */
567 debug_printf ("HEW: Got clone event "
568 "from LWP %ld, new child is LWP %ld\n",
569 lwpid_of (event_thr
), new_pid
);
571 ptid
= ptid_build (pid_of (event_thr
), new_pid
, 0);
572 new_lwp
= add_lwp (ptid
);
574 /* Either we're going to immediately resume the new thread
575 or leave it stopped. linux_resume_one_lwp is a nop if it
576 thinks the thread is currently running, so set this first
577 before calling linux_resume_one_lwp. */
578 new_lwp
->stopped
= 1;
580 /* If we're suspending all threads, leave this one suspended
582 if (stopping_threads
== STOPPING_AND_SUSPENDING_THREADS
)
583 new_lwp
->suspended
= 1;
585 /* Normally we will get the pending SIGSTOP. But in some cases
586 we might get another signal delivered to the group first.
587 If we do get another signal, be sure not to lose it. */
588 if (WSTOPSIG (status
) != SIGSTOP
)
590 new_lwp
->stop_expected
= 1;
591 new_lwp
->status_pending_p
= 1;
592 new_lwp
->status_pending
= status
;
594 else if (report_thread_events
)
596 new_lwp
->waitstatus
.kind
= TARGET_WAITKIND_THREAD_CREATED
;
597 new_lwp
->status_pending_p
= 1;
598 new_lwp
->status_pending
= status
;
601 /* Don't report the event. */
604 else if (event
== PTRACE_EVENT_VFORK_DONE
)
606 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_VFORK_DONE
;
608 /* Report the event. */
611 else if (event
== PTRACE_EVENT_EXEC
&& report_exec_events
)
613 struct process_info
*proc
;
619 debug_printf ("HEW: Got exec event from LWP %ld\n",
620 lwpid_of (event_thr
));
623 /* Get the event ptid. */
624 event_ptid
= ptid_of (event_thr
);
625 event_pid
= ptid_get_pid (event_ptid
);
627 /* Delete the execing process and all its threads. */
628 proc
= get_thread_process (event_thr
);
630 current_thread
= NULL
;
632 /* Create a new process/lwp/thread. */
633 proc
= linux_add_process (event_pid
, 0);
634 event_lwp
= add_lwp (event_ptid
);
635 event_thr
= get_lwp_thread (event_lwp
);
636 gdb_assert (current_thread
== event_thr
);
637 linux_arch_setup_thread (event_thr
);
639 /* Set the event status. */
640 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_EXECD
;
641 event_lwp
->waitstatus
.value
.execd_pathname
642 = xstrdup (linux_proc_pid_to_exec_file (lwpid_of (event_thr
)));
644 /* Mark the exec status as pending. */
645 event_lwp
->stopped
= 1;
646 event_lwp
->status_pending_p
= 1;
647 event_lwp
->status_pending
= wstat
;
648 event_thr
->last_resume_kind
= resume_continue
;
649 event_thr
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
651 /* Report the event. */
652 *orig_event_lwp
= event_lwp
;
656 internal_error (__FILE__
, __LINE__
, _("unknown ptrace event %d"), event
);
659 /* Return the PC as read from the regcache of LWP, without any
663 get_pc (struct lwp_info
*lwp
)
665 struct thread_info
*saved_thread
;
666 struct regcache
*regcache
;
669 if (the_low_target
.get_pc
== NULL
)
672 saved_thread
= current_thread
;
673 current_thread
= get_lwp_thread (lwp
);
675 regcache
= get_thread_regcache (current_thread
, 1);
676 pc
= (*the_low_target
.get_pc
) (regcache
);
679 debug_printf ("pc is 0x%lx\n", (long) pc
);
681 current_thread
= saved_thread
;
685 /* This function should only be called if LWP got a SIGTRAP.
686 The SIGTRAP could mean several things.
688 On i386, where decr_pc_after_break is non-zero:
690 If we were single-stepping this process using PTRACE_SINGLESTEP, we
691 will get only the one SIGTRAP. The value of $eip will be the next
692 instruction. If the instruction we stepped over was a breakpoint,
693 we need to decrement the PC.
695 If we continue the process using PTRACE_CONT, we will get a
696 SIGTRAP when we hit a breakpoint. The value of $eip will be
697 the instruction after the breakpoint (i.e. needs to be
698 decremented). If we report the SIGTRAP to GDB, we must also
699 report the undecremented PC. If the breakpoint is removed, we
700 must resume at the decremented PC.
702 On a non-decr_pc_after_break machine with hardware or kernel
705 If we either single-step a breakpoint instruction, or continue and
706 hit a breakpoint instruction, our PC will point at the breakpoint
710 check_stopped_by_breakpoint (struct lwp_info
*lwp
)
713 CORE_ADDR sw_breakpoint_pc
;
714 struct thread_info
*saved_thread
;
715 #if USE_SIGTRAP_SIGINFO
719 if (the_low_target
.get_pc
== NULL
)
723 sw_breakpoint_pc
= pc
- the_low_target
.decr_pc_after_break
;
725 /* breakpoint_at reads from the current thread. */
726 saved_thread
= current_thread
;
727 current_thread
= get_lwp_thread (lwp
);
729 #if USE_SIGTRAP_SIGINFO
730 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
731 (PTRACE_TYPE_ARG3
) 0, &siginfo
) == 0)
733 if (siginfo
.si_signo
== SIGTRAP
)
735 if (GDB_ARCH_IS_TRAP_BRKPT (siginfo
.si_code
))
739 struct thread_info
*thr
= get_lwp_thread (lwp
);
741 debug_printf ("CSBB: %s stopped by software breakpoint\n",
742 target_pid_to_str (ptid_of (thr
)));
745 /* Back up the PC if necessary. */
746 if (pc
!= sw_breakpoint_pc
)
748 struct regcache
*regcache
749 = get_thread_regcache (current_thread
, 1);
750 (*the_low_target
.set_pc
) (regcache
, sw_breakpoint_pc
);
753 lwp
->stop_pc
= sw_breakpoint_pc
;
754 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
755 current_thread
= saved_thread
;
758 else if (siginfo
.si_code
== TRAP_HWBKPT
)
762 struct thread_info
*thr
= get_lwp_thread (lwp
);
764 debug_printf ("CSBB: %s stopped by hardware "
765 "breakpoint/watchpoint\n",
766 target_pid_to_str (ptid_of (thr
)));
770 lwp
->stop_reason
= TARGET_STOPPED_BY_HW_BREAKPOINT
;
771 current_thread
= saved_thread
;
774 else if (siginfo
.si_code
== TRAP_TRACE
)
778 struct thread_info
*thr
= get_lwp_thread (lwp
);
780 debug_printf ("CSBB: %s stopped by trace\n",
781 target_pid_to_str (ptid_of (thr
)));
784 lwp
->stop_reason
= TARGET_STOPPED_BY_SINGLE_STEP
;
789 /* We may have just stepped a breakpoint instruction. E.g., in
790 non-stop mode, GDB first tells the thread A to step a range, and
791 then the user inserts a breakpoint inside the range. In that
792 case we need to report the breakpoint PC. */
793 if ((!lwp
->stepping
|| lwp
->stop_pc
== sw_breakpoint_pc
)
794 && (*the_low_target
.breakpoint_at
) (sw_breakpoint_pc
))
798 struct thread_info
*thr
= get_lwp_thread (lwp
);
800 debug_printf ("CSBB: %s stopped by software breakpoint\n",
801 target_pid_to_str (ptid_of (thr
)));
804 /* Back up the PC if necessary. */
805 if (pc
!= sw_breakpoint_pc
)
807 struct regcache
*regcache
808 = get_thread_regcache (current_thread
, 1);
809 (*the_low_target
.set_pc
) (regcache
, sw_breakpoint_pc
);
812 lwp
->stop_pc
= sw_breakpoint_pc
;
813 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
814 current_thread
= saved_thread
;
818 if (hardware_breakpoint_inserted_here (pc
))
822 struct thread_info
*thr
= get_lwp_thread (lwp
);
824 debug_printf ("CSBB: %s stopped by hardware breakpoint\n",
825 target_pid_to_str (ptid_of (thr
)));
829 lwp
->stop_reason
= TARGET_STOPPED_BY_HW_BREAKPOINT
;
830 current_thread
= saved_thread
;
835 current_thread
= saved_thread
;
839 static struct lwp_info
*
840 add_lwp (ptid_t ptid
)
842 struct lwp_info
*lwp
;
844 lwp
= XCNEW (struct lwp_info
);
846 lwp
->waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
848 if (the_low_target
.new_thread
!= NULL
)
849 the_low_target
.new_thread (lwp
);
851 lwp
->thread
= add_thread (ptid
, lwp
);
856 /* Start an inferior process and returns its pid.
857 ALLARGS is a vector of program-name and args. */
860 linux_create_inferior (char *program
, char **allargs
)
862 struct lwp_info
*new_lwp
;
865 struct cleanup
*restore_personality
866 = maybe_disable_address_space_randomization (disable_randomization
);
868 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
874 perror_with_name ("fork");
879 ptrace (PTRACE_TRACEME
, 0, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
883 /* If gdbserver is connected to gdb via stdio, redirect the inferior's
884 stdout to stderr so that inferior i/o doesn't corrupt the connection.
885 Also, redirect stdin to /dev/null. */
886 if (remote_connection_is_stdio ())
889 open ("/dev/null", O_RDONLY
);
891 if (write (2, "stdin/stdout redirected\n",
892 sizeof ("stdin/stdout redirected\n") - 1) < 0)
894 /* Errors ignored. */;
898 execv (program
, allargs
);
900 execvp (program
, allargs
);
902 fprintf (stderr
, "Cannot exec %s: %s.\n", program
,
908 do_cleanups (restore_personality
);
910 linux_add_process (pid
, 0);
912 ptid
= ptid_build (pid
, pid
, 0);
913 new_lwp
= add_lwp (ptid
);
914 new_lwp
->must_set_ptrace_flags
= 1;
919 /* Implement the post_create_inferior target_ops method. */
922 linux_post_create_inferior (void)
924 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
928 if (lwp
->must_set_ptrace_flags
)
930 struct process_info
*proc
= current_process ();
931 int options
= linux_low_ptrace_options (proc
->attached
);
933 linux_enable_event_reporting (lwpid_of (current_thread
), options
);
934 lwp
->must_set_ptrace_flags
= 0;
938 /* Attach to an inferior process. Returns 0 on success, ERRNO on
942 linux_attach_lwp (ptid_t ptid
)
944 struct lwp_info
*new_lwp
;
945 int lwpid
= ptid_get_lwp (ptid
);
947 if (ptrace (PTRACE_ATTACH
, lwpid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0)
951 new_lwp
= add_lwp (ptid
);
953 /* We need to wait for SIGSTOP before being able to make the next
954 ptrace call on this LWP. */
955 new_lwp
->must_set_ptrace_flags
= 1;
957 if (linux_proc_pid_is_stopped (lwpid
))
960 debug_printf ("Attached to a stopped process\n");
962 /* The process is definitely stopped. It is in a job control
963 stop, unless the kernel predates the TASK_STOPPED /
964 TASK_TRACED distinction, in which case it might be in a
965 ptrace stop. Make sure it is in a ptrace stop; from there we
966 can kill it, signal it, et cetera.
968 First make sure there is a pending SIGSTOP. Since we are
969 already attached, the process can not transition from stopped
970 to running without a PTRACE_CONT; so we know this signal will
971 go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
972 probably already in the queue (unless this kernel is old
973 enough to use TASK_STOPPED for ptrace stops); but since
974 SIGSTOP is not an RT signal, it can only be queued once. */
975 kill_lwp (lwpid
, SIGSTOP
);
977 /* Finally, resume the stopped process. This will deliver the
978 SIGSTOP (or a higher priority signal, just like normal
979 PTRACE_ATTACH), which we'll catch later on. */
980 ptrace (PTRACE_CONT
, lwpid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
983 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
986 There are several cases to consider here:
988 1) gdbserver has already attached to the process and is being notified
989 of a new thread that is being created.
990 In this case we should ignore that SIGSTOP and resume the
991 process. This is handled below by setting stop_expected = 1,
992 and the fact that add_thread sets last_resume_kind ==
995 2) This is the first thread (the process thread), and we're attaching
996 to it via attach_inferior.
997 In this case we want the process thread to stop.
998 This is handled by having linux_attach set last_resume_kind ==
999 resume_stop after we return.
1001 If the pid we are attaching to is also the tgid, we attach to and
1002 stop all the existing threads. Otherwise, we attach to pid and
1003 ignore any other threads in the same group as this pid.
1005 3) GDB is connecting to gdbserver and is requesting an enumeration of all
1007 In this case we want the thread to stop.
1008 FIXME: This case is currently not properly handled.
1009 We should wait for the SIGSTOP but don't. Things work apparently
1010 because enough time passes between when we ptrace (ATTACH) and when
1011 gdb makes the next ptrace call on the thread.
1013 On the other hand, if we are currently trying to stop all threads, we
1014 should treat the new thread as if we had sent it a SIGSTOP. This works
1015 because we are guaranteed that the add_lwp call above added us to the
1016 end of the list, and so the new thread has not yet reached
1017 wait_for_sigstop (but will). */
1018 new_lwp
->stop_expected
= 1;
1023 /* Callback for linux_proc_attach_tgid_threads. Attach to PTID if not
1024 already attached. Returns true if a new LWP is found, false
1028 attach_proc_task_lwp_callback (ptid_t ptid
)
1030 /* Is this a new thread? */
1031 if (find_thread_ptid (ptid
) == NULL
)
1033 int lwpid
= ptid_get_lwp (ptid
);
1037 debug_printf ("Found new lwp %d\n", lwpid
);
1039 err
= linux_attach_lwp (ptid
);
1041 /* Be quiet if we simply raced with the thread exiting. EPERM
1042 is returned if the thread's task still exists, and is marked
1043 as exited or zombie, as well as other conditions, so in that
1044 case, confirm the status in /proc/PID/status. */
1046 || (err
== EPERM
&& linux_proc_pid_is_gone (lwpid
)))
1050 debug_printf ("Cannot attach to lwp %d: "
1051 "thread is gone (%d: %s)\n",
1052 lwpid
, err
, strerror (err
));
1057 warning (_("Cannot attach to lwp %d: %s"),
1059 linux_ptrace_attach_fail_reason_string (ptid
, err
));
1067 static void async_file_mark (void);
1069 /* Attach to PID. If PID is the tgid, attach to it and all
1073 linux_attach (unsigned long pid
)
1075 struct process_info
*proc
;
1076 struct thread_info
*initial_thread
;
1077 ptid_t ptid
= ptid_build (pid
, pid
, 0);
1080 /* Attach to PID. We will check for other threads
1082 err
= linux_attach_lwp (ptid
);
1084 error ("Cannot attach to process %ld: %s",
1085 pid
, linux_ptrace_attach_fail_reason_string (ptid
, err
));
1087 proc
= linux_add_process (pid
, 1);
1089 /* Don't ignore the initial SIGSTOP if we just attached to this
1090 process. It will be collected by wait shortly. */
1091 initial_thread
= find_thread_ptid (ptid_build (pid
, pid
, 0));
1092 initial_thread
->last_resume_kind
= resume_stop
;
1094 /* We must attach to every LWP. If /proc is mounted, use that to
1095 find them now. On the one hand, the inferior may be using raw
1096 clone instead of using pthreads. On the other hand, even if it
1097 is using pthreads, GDB may not be connected yet (thread_db needs
1098 to do symbol lookups, through qSymbol). Also, thread_db walks
1099 structures in the inferior's address space to find the list of
1100 threads/LWPs, and those structures may well be corrupted. Note
1101 that once thread_db is loaded, we'll still use it to list threads
1102 and associate pthread info with each LWP. */
1103 linux_proc_attach_tgid_threads (pid
, attach_proc_task_lwp_callback
);
1105 /* GDB will shortly read the xml target description for this
1106 process, to figure out the process' architecture. But the target
1107 description is only filled in when the first process/thread in
1108 the thread group reports its initial PTRACE_ATTACH SIGSTOP. Do
1109 that now, otherwise, if GDB is fast enough, it could read the
1110 target description _before_ that initial stop. */
1113 struct lwp_info
*lwp
;
1115 ptid_t pid_ptid
= pid_to_ptid (pid
);
1117 lwpid
= linux_wait_for_event_filtered (pid_ptid
, pid_ptid
,
1119 gdb_assert (lwpid
> 0);
1121 lwp
= find_lwp_pid (pid_to_ptid (lwpid
));
1123 if (!WIFSTOPPED (wstat
) || WSTOPSIG (wstat
) != SIGSTOP
)
1125 lwp
->status_pending_p
= 1;
1126 lwp
->status_pending
= wstat
;
1129 initial_thread
->last_resume_kind
= resume_continue
;
1133 gdb_assert (proc
->tdesc
!= NULL
);
1146 second_thread_of_pid_p (struct inferior_list_entry
*entry
, void *args
)
1148 struct counter
*counter
= (struct counter
*) args
;
1150 if (ptid_get_pid (entry
->id
) == counter
->pid
)
1152 if (++counter
->count
> 1)
1160 last_thread_of_process_p (int pid
)
1162 struct counter counter
= { pid
, 0 };
1164 return (find_inferior (&all_threads
,
1165 second_thread_of_pid_p
, &counter
) == NULL
);
1171 linux_kill_one_lwp (struct lwp_info
*lwp
)
1173 struct thread_info
*thr
= get_lwp_thread (lwp
);
1174 int pid
= lwpid_of (thr
);
1176 /* PTRACE_KILL is unreliable. After stepping into a signal handler,
1177 there is no signal context, and ptrace(PTRACE_KILL) (or
1178 ptrace(PTRACE_CONT, SIGKILL), pretty much the same) acts like
1179 ptrace(CONT, pid, 0,0) and just resumes the tracee. A better
1180 alternative is to kill with SIGKILL. We only need one SIGKILL
1181 per process, not one for each thread. But since we still support
1182 support debugging programs using raw clone without CLONE_THREAD,
1183 we send one for each thread. For years, we used PTRACE_KILL
1184 only, so we're being a bit paranoid about some old kernels where
1185 PTRACE_KILL might work better (dubious if there are any such, but
1186 that's why it's paranoia), so we try SIGKILL first, PTRACE_KILL
1187 second, and so we're fine everywhere. */
1190 kill_lwp (pid
, SIGKILL
);
1193 int save_errno
= errno
;
1195 debug_printf ("LKL: kill_lwp (SIGKILL) %s, 0, 0 (%s)\n",
1196 target_pid_to_str (ptid_of (thr
)),
1197 save_errno
? strerror (save_errno
) : "OK");
1201 ptrace (PTRACE_KILL
, pid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
1204 int save_errno
= errno
;
1206 debug_printf ("LKL: PTRACE_KILL %s, 0, 0 (%s)\n",
1207 target_pid_to_str (ptid_of (thr
)),
1208 save_errno
? strerror (save_errno
) : "OK");
1212 /* Kill LWP and wait for it to die. */
1215 kill_wait_lwp (struct lwp_info
*lwp
)
1217 struct thread_info
*thr
= get_lwp_thread (lwp
);
1218 int pid
= ptid_get_pid (ptid_of (thr
));
1219 int lwpid
= ptid_get_lwp (ptid_of (thr
));
1224 debug_printf ("kwl: killing lwp %d, for pid: %d\n", lwpid
, pid
);
1228 linux_kill_one_lwp (lwp
);
1230 /* Make sure it died. Notes:
1232 - The loop is most likely unnecessary.
1234 - We don't use linux_wait_for_event as that could delete lwps
1235 while we're iterating over them. We're not interested in
1236 any pending status at this point, only in making sure all
1237 wait status on the kernel side are collected until the
1240 - We don't use __WALL here as the __WALL emulation relies on
1241 SIGCHLD, and killing a stopped process doesn't generate
1242 one, nor an exit status.
1244 res
= my_waitpid (lwpid
, &wstat
, 0);
1245 if (res
== -1 && errno
== ECHILD
)
1246 res
= my_waitpid (lwpid
, &wstat
, __WCLONE
);
1247 } while (res
> 0 && WIFSTOPPED (wstat
));
1249 /* Even if it was stopped, the child may have already disappeared.
1250 E.g., if it was killed by SIGKILL. */
1251 if (res
< 0 && errno
!= ECHILD
)
1252 perror_with_name ("kill_wait_lwp");
1255 /* Callback for `find_inferior'. Kills an lwp of a given process,
1256 except the leader. */
1259 kill_one_lwp_callback (struct inferior_list_entry
*entry
, void *args
)
1261 struct thread_info
*thread
= (struct thread_info
*) entry
;
1262 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1263 int pid
= * (int *) args
;
1265 if (ptid_get_pid (entry
->id
) != pid
)
1268 /* We avoid killing the first thread here, because of a Linux kernel (at
1269 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
1270 the children get a chance to be reaped, it will remain a zombie
1273 if (lwpid_of (thread
) == pid
)
1276 debug_printf ("lkop: is last of process %s\n",
1277 target_pid_to_str (entry
->id
));
1281 kill_wait_lwp (lwp
);
1286 linux_kill (int pid
)
1288 struct process_info
*process
;
1289 struct lwp_info
*lwp
;
1291 process
= find_process_pid (pid
);
1292 if (process
== NULL
)
1295 /* If we're killing a running inferior, make sure it is stopped
1296 first, as PTRACE_KILL will not work otherwise. */
1297 stop_all_lwps (0, NULL
);
1299 find_inferior (&all_threads
, kill_one_lwp_callback
, &pid
);
1301 /* See the comment in linux_kill_one_lwp. We did not kill the first
1302 thread in the list, so do so now. */
1303 lwp
= find_lwp_pid (pid_to_ptid (pid
));
1308 debug_printf ("lk_1: cannot find lwp for pid: %d\n",
1312 kill_wait_lwp (lwp
);
1314 the_target
->mourn (process
);
1316 /* Since we presently can only stop all lwps of all processes, we
1317 need to unstop lwps of other processes. */
1318 unstop_all_lwps (0, NULL
);
1322 /* Get pending signal of THREAD, for detaching purposes. This is the
1323 signal the thread last stopped for, which we need to deliver to the
1324 thread when detaching, otherwise, it'd be suppressed/lost. */
1327 get_detach_signal (struct thread_info
*thread
)
1329 enum gdb_signal signo
= GDB_SIGNAL_0
;
1331 struct lwp_info
*lp
= get_thread_lwp (thread
);
1333 if (lp
->status_pending_p
)
1334 status
= lp
->status_pending
;
1337 /* If the thread had been suspended by gdbserver, and it stopped
1338 cleanly, then it'll have stopped with SIGSTOP. But we don't
1339 want to deliver that SIGSTOP. */
1340 if (thread
->last_status
.kind
!= TARGET_WAITKIND_STOPPED
1341 || thread
->last_status
.value
.sig
== GDB_SIGNAL_0
)
1344 /* Otherwise, we may need to deliver the signal we
1346 status
= lp
->last_status
;
1349 if (!WIFSTOPPED (status
))
1352 debug_printf ("GPS: lwp %s hasn't stopped: no pending signal\n",
1353 target_pid_to_str (ptid_of (thread
)));
1357 /* Extended wait statuses aren't real SIGTRAPs. */
1358 if (WSTOPSIG (status
) == SIGTRAP
&& linux_is_extended_waitstatus (status
))
1361 debug_printf ("GPS: lwp %s had stopped with extended "
1362 "status: no pending signal\n",
1363 target_pid_to_str (ptid_of (thread
)));
1367 signo
= gdb_signal_from_host (WSTOPSIG (status
));
1369 if (program_signals_p
&& !program_signals
[signo
])
1372 debug_printf ("GPS: lwp %s had signal %s, but it is in nopass state\n",
1373 target_pid_to_str (ptid_of (thread
)),
1374 gdb_signal_to_string (signo
));
1377 else if (!program_signals_p
1378 /* If we have no way to know which signals GDB does not
1379 want to have passed to the program, assume
1380 SIGTRAP/SIGINT, which is GDB's default. */
1381 && (signo
== GDB_SIGNAL_TRAP
|| signo
== GDB_SIGNAL_INT
))
1384 debug_printf ("GPS: lwp %s had signal %s, "
1385 "but we don't know if we should pass it. "
1386 "Default to not.\n",
1387 target_pid_to_str (ptid_of (thread
)),
1388 gdb_signal_to_string (signo
));
1394 debug_printf ("GPS: lwp %s has pending signal %s: delivering it.\n",
1395 target_pid_to_str (ptid_of (thread
)),
1396 gdb_signal_to_string (signo
));
1398 return WSTOPSIG (status
);
1403 linux_detach_one_lwp (struct inferior_list_entry
*entry
, void *args
)
1405 struct thread_info
*thread
= (struct thread_info
*) entry
;
1406 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1407 int pid
= * (int *) args
;
1410 if (ptid_get_pid (entry
->id
) != pid
)
1413 /* If there is a pending SIGSTOP, get rid of it. */
1414 if (lwp
->stop_expected
)
1417 debug_printf ("Sending SIGCONT to %s\n",
1418 target_pid_to_str (ptid_of (thread
)));
1420 kill_lwp (lwpid_of (thread
), SIGCONT
);
1421 lwp
->stop_expected
= 0;
1424 /* Flush any pending changes to the process's registers. */
1425 regcache_invalidate_thread (thread
);
1427 /* Pass on any pending signal for this thread. */
1428 sig
= get_detach_signal (thread
);
1430 /* Finally, let it resume. */
1431 if (the_low_target
.prepare_to_resume
!= NULL
)
1432 the_low_target
.prepare_to_resume (lwp
);
1433 if (ptrace (PTRACE_DETACH
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
1434 (PTRACE_TYPE_ARG4
) (long) sig
) < 0)
1435 error (_("Can't detach %s: %s"),
1436 target_pid_to_str (ptid_of (thread
)),
1444 linux_detach (int pid
)
1446 struct process_info
*process
;
1448 process
= find_process_pid (pid
);
1449 if (process
== NULL
)
1452 /* As there's a step over already in progress, let it finish first,
1453 otherwise nesting a stabilize_threads operation on top gets real
1455 complete_ongoing_step_over ();
1457 /* Stop all threads before detaching. First, ptrace requires that
1458 the thread is stopped to sucessfully detach. Second, thread_db
1459 may need to uninstall thread event breakpoints from memory, which
1460 only works with a stopped process anyway. */
1461 stop_all_lwps (0, NULL
);
1463 #ifdef USE_THREAD_DB
1464 thread_db_detach (process
);
1467 /* Stabilize threads (move out of jump pads). */
1468 stabilize_threads ();
1470 find_inferior (&all_threads
, linux_detach_one_lwp
, &pid
);
1472 the_target
->mourn (process
);
1474 /* Since we presently can only stop all lwps of all processes, we
1475 need to unstop lwps of other processes. */
1476 unstop_all_lwps (0, NULL
);
1480 /* Remove all LWPs that belong to process PROC from the lwp list. */
1483 delete_lwp_callback (struct inferior_list_entry
*entry
, void *proc
)
1485 struct thread_info
*thread
= (struct thread_info
*) entry
;
1486 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1487 struct process_info
*process
= (struct process_info
*) proc
;
1489 if (pid_of (thread
) == pid_of (process
))
1496 linux_mourn (struct process_info
*process
)
1498 struct process_info_private
*priv
;
1500 #ifdef USE_THREAD_DB
1501 thread_db_mourn (process
);
1504 find_inferior (&all_threads
, delete_lwp_callback
, process
);
1506 /* Freeing all private data. */
1507 priv
= process
->priv
;
1508 free (priv
->arch_private
);
1510 process
->priv
= NULL
;
1512 remove_process (process
);
1516 linux_join (int pid
)
1521 ret
= my_waitpid (pid
, &status
, 0);
1522 if (WIFEXITED (status
) || WIFSIGNALED (status
))
1524 } while (ret
!= -1 || errno
!= ECHILD
);
1527 /* Return nonzero if the given thread is still alive. */
1529 linux_thread_alive (ptid_t ptid
)
1531 struct lwp_info
*lwp
= find_lwp_pid (ptid
);
1533 /* We assume we always know if a thread exits. If a whole process
1534 exited but we still haven't been able to report it to GDB, we'll
1535 hold on to the last lwp of the dead process. */
1537 return !lwp_is_marked_dead (lwp
);
1542 /* Return 1 if this lwp still has an interesting status pending. If
1543 not (e.g., it had stopped for a breakpoint that is gone), return
1547 thread_still_has_status_pending_p (struct thread_info
*thread
)
1549 struct lwp_info
*lp
= get_thread_lwp (thread
);
1551 if (!lp
->status_pending_p
)
1554 if (thread
->last_resume_kind
!= resume_stop
1555 && (lp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
1556 || lp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
1558 struct thread_info
*saved_thread
;
1562 gdb_assert (lp
->last_status
!= 0);
1566 saved_thread
= current_thread
;
1567 current_thread
= thread
;
1569 if (pc
!= lp
->stop_pc
)
1572 debug_printf ("PC of %ld changed\n",
1577 #if !USE_SIGTRAP_SIGINFO
1578 else if (lp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
1579 && !(*the_low_target
.breakpoint_at
) (pc
))
1582 debug_printf ("previous SW breakpoint of %ld gone\n",
1586 else if (lp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
1587 && !hardware_breakpoint_inserted_here (pc
))
1590 debug_printf ("previous HW breakpoint of %ld gone\n",
1596 current_thread
= saved_thread
;
1601 debug_printf ("discarding pending breakpoint status\n");
1602 lp
->status_pending_p
= 0;
1610 /* Returns true if LWP is resumed from the client's perspective. */
1613 lwp_resumed (struct lwp_info
*lwp
)
1615 struct thread_info
*thread
= get_lwp_thread (lwp
);
1617 if (thread
->last_resume_kind
!= resume_stop
)
1620 /* Did gdb send us a `vCont;t', but we haven't reported the
1621 corresponding stop to gdb yet? If so, the thread is still
1622 resumed/running from gdb's perspective. */
1623 if (thread
->last_resume_kind
== resume_stop
1624 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
)
1630 /* Return 1 if this lwp has an interesting status pending. */
1632 status_pending_p_callback (struct inferior_list_entry
*entry
, void *arg
)
1634 struct thread_info
*thread
= (struct thread_info
*) entry
;
1635 struct lwp_info
*lp
= get_thread_lwp (thread
);
1636 ptid_t ptid
= * (ptid_t
*) arg
;
1638 /* Check if we're only interested in events from a specific process
1639 or a specific LWP. */
1640 if (!ptid_match (ptid_of (thread
), ptid
))
1643 if (!lwp_resumed (lp
))
1646 if (lp
->status_pending_p
1647 && !thread_still_has_status_pending_p (thread
))
1649 linux_resume_one_lwp (lp
, lp
->stepping
, GDB_SIGNAL_0
, NULL
);
1653 return lp
->status_pending_p
;
1657 same_lwp (struct inferior_list_entry
*entry
, void *data
)
1659 ptid_t ptid
= *(ptid_t
*) data
;
1662 if (ptid_get_lwp (ptid
) != 0)
1663 lwp
= ptid_get_lwp (ptid
);
1665 lwp
= ptid_get_pid (ptid
);
1667 if (ptid_get_lwp (entry
->id
) == lwp
)
1674 find_lwp_pid (ptid_t ptid
)
1676 struct inferior_list_entry
*thread
1677 = find_inferior (&all_threads
, same_lwp
, &ptid
);
1682 return get_thread_lwp ((struct thread_info
*) thread
);
1685 /* Return the number of known LWPs in the tgid given by PID. */
1690 struct inferior_list_entry
*inf
, *tmp
;
1693 ALL_INFERIORS (&all_threads
, inf
, tmp
)
1695 if (ptid_get_pid (inf
->id
) == pid
)
1702 /* The arguments passed to iterate_over_lwps. */
1704 struct iterate_over_lwps_args
1706 /* The FILTER argument passed to iterate_over_lwps. */
1709 /* The CALLBACK argument passed to iterate_over_lwps. */
1710 iterate_over_lwps_ftype
*callback
;
1712 /* The DATA argument passed to iterate_over_lwps. */
1716 /* Callback for find_inferior used by iterate_over_lwps to filter
1717 calls to the callback supplied to that function. Returning a
1718 nonzero value causes find_inferiors to stop iterating and return
1719 the current inferior_list_entry. Returning zero indicates that
1720 find_inferiors should continue iterating. */
1723 iterate_over_lwps_filter (struct inferior_list_entry
*entry
, void *args_p
)
1725 struct iterate_over_lwps_args
*args
1726 = (struct iterate_over_lwps_args
*) args_p
;
1728 if (ptid_match (entry
->id
, args
->filter
))
1730 struct thread_info
*thr
= (struct thread_info
*) entry
;
1731 struct lwp_info
*lwp
= get_thread_lwp (thr
);
1733 return (*args
->callback
) (lwp
, args
->data
);
1739 /* See nat/linux-nat.h. */
1742 iterate_over_lwps (ptid_t filter
,
1743 iterate_over_lwps_ftype callback
,
1746 struct iterate_over_lwps_args args
= {filter
, callback
, data
};
1747 struct inferior_list_entry
*entry
;
1749 entry
= find_inferior (&all_threads
, iterate_over_lwps_filter
, &args
);
1753 return get_thread_lwp ((struct thread_info
*) entry
);
1756 /* Detect zombie thread group leaders, and "exit" them. We can't reap
1757 their exits until all other threads in the group have exited. */
1760 check_zombie_leaders (void)
1762 struct process_info
*proc
, *tmp
;
1764 ALL_PROCESSES (proc
, tmp
)
1766 pid_t leader_pid
= pid_of (proc
);
1767 struct lwp_info
*leader_lp
;
1769 leader_lp
= find_lwp_pid (pid_to_ptid (leader_pid
));
1772 debug_printf ("leader_pid=%d, leader_lp!=NULL=%d, "
1773 "num_lwps=%d, zombie=%d\n",
1774 leader_pid
, leader_lp
!= NULL
, num_lwps (leader_pid
),
1775 linux_proc_pid_is_zombie (leader_pid
));
1777 if (leader_lp
!= NULL
&& !leader_lp
->stopped
1778 /* Check if there are other threads in the group, as we may
1779 have raced with the inferior simply exiting. */
1780 && !last_thread_of_process_p (leader_pid
)
1781 && linux_proc_pid_is_zombie (leader_pid
))
1783 /* A leader zombie can mean one of two things:
1785 - It exited, and there's an exit status pending
1786 available, or only the leader exited (not the whole
1787 program). In the latter case, we can't waitpid the
1788 leader's exit status until all other threads are gone.
1790 - There are 3 or more threads in the group, and a thread
1791 other than the leader exec'd. On an exec, the Linux
1792 kernel destroys all other threads (except the execing
1793 one) in the thread group, and resets the execing thread's
1794 tid to the tgid. No exit notification is sent for the
1795 execing thread -- from the ptracer's perspective, it
1796 appears as though the execing thread just vanishes.
1797 Until we reap all other threads except the leader and the
1798 execing thread, the leader will be zombie, and the
1799 execing thread will be in `D (disc sleep)'. As soon as
1800 all other threads are reaped, the execing thread changes
1801 it's tid to the tgid, and the previous (zombie) leader
1802 vanishes, giving place to the "new" leader. We could try
1803 distinguishing the exit and exec cases, by waiting once
1804 more, and seeing if something comes out, but it doesn't
1805 sound useful. The previous leader _does_ go away, and
1806 we'll re-add the new one once we see the exec event
1807 (which is just the same as what would happen if the
1808 previous leader did exit voluntarily before some other
1813 "CZL: Thread group leader %d zombie "
1814 "(it exited, or another thread execd).\n",
1817 delete_lwp (leader_lp
);
1822 /* Callback for `find_inferior'. Returns the first LWP that is not
1823 stopped. ARG is a PTID filter. */
1826 not_stopped_callback (struct inferior_list_entry
*entry
, void *arg
)
1828 struct thread_info
*thr
= (struct thread_info
*) entry
;
1829 struct lwp_info
*lwp
;
1830 ptid_t filter
= *(ptid_t
*) arg
;
1832 if (!ptid_match (ptid_of (thr
), filter
))
1835 lwp
= get_thread_lwp (thr
);
1842 /* Increment LWP's suspend count. */
1845 lwp_suspended_inc (struct lwp_info
*lwp
)
1849 if (debug_threads
&& lwp
->suspended
> 4)
1851 struct thread_info
*thread
= get_lwp_thread (lwp
);
1853 debug_printf ("LWP %ld has a suspiciously high suspend count,"
1854 " suspended=%d\n", lwpid_of (thread
), lwp
->suspended
);
1858 /* Decrement LWP's suspend count. */
1861 lwp_suspended_decr (struct lwp_info
*lwp
)
1865 if (lwp
->suspended
< 0)
1867 struct thread_info
*thread
= get_lwp_thread (lwp
);
1869 internal_error (__FILE__
, __LINE__
,
1870 "unsuspend LWP %ld, suspended=%d\n", lwpid_of (thread
),
1875 /* This function should only be called if the LWP got a SIGTRAP.
1877 Handle any tracepoint steps or hits. Return true if a tracepoint
1878 event was handled, 0 otherwise. */
1881 handle_tracepoints (struct lwp_info
*lwp
)
1883 struct thread_info
*tinfo
= get_lwp_thread (lwp
);
1884 int tpoint_related_event
= 0;
1886 gdb_assert (lwp
->suspended
== 0);
1888 /* If this tracepoint hit causes a tracing stop, we'll immediately
1889 uninsert tracepoints. To do this, we temporarily pause all
1890 threads, unpatch away, and then unpause threads. We need to make
1891 sure the unpausing doesn't resume LWP too. */
1892 lwp_suspended_inc (lwp
);
1894 /* And we need to be sure that any all-threads-stopping doesn't try
1895 to move threads out of the jump pads, as it could deadlock the
1896 inferior (LWP could be in the jump pad, maybe even holding the
1899 /* Do any necessary step collect actions. */
1900 tpoint_related_event
|= tracepoint_finished_step (tinfo
, lwp
->stop_pc
);
1902 tpoint_related_event
|= handle_tracepoint_bkpts (tinfo
, lwp
->stop_pc
);
1904 /* See if we just hit a tracepoint and do its main collect
1906 tpoint_related_event
|= tracepoint_was_hit (tinfo
, lwp
->stop_pc
);
1908 lwp_suspended_decr (lwp
);
1910 gdb_assert (lwp
->suspended
== 0);
1911 gdb_assert (!stabilizing_threads
|| lwp
->collecting_fast_tracepoint
);
1913 if (tpoint_related_event
)
1916 debug_printf ("got a tracepoint event\n");
1923 /* Convenience wrapper. Returns true if LWP is presently collecting a
1927 linux_fast_tracepoint_collecting (struct lwp_info
*lwp
,
1928 struct fast_tpoint_collect_status
*status
)
1930 CORE_ADDR thread_area
;
1931 struct thread_info
*thread
= get_lwp_thread (lwp
);
1933 if (the_low_target
.get_thread_area
== NULL
)
1936 /* Get the thread area address. This is used to recognize which
1937 thread is which when tracing with the in-process agent library.
1938 We don't read anything from the address, and treat it as opaque;
1939 it's the address itself that we assume is unique per-thread. */
1940 if ((*the_low_target
.get_thread_area
) (lwpid_of (thread
), &thread_area
) == -1)
1943 return fast_tracepoint_collecting (thread_area
, lwp
->stop_pc
, status
);
1946 /* The reason we resume in the caller, is because we want to be able
1947 to pass lwp->status_pending as WSTAT, and we need to clear
1948 status_pending_p before resuming, otherwise, linux_resume_one_lwp
1949 refuses to resume. */
1952 maybe_move_out_of_jump_pad (struct lwp_info
*lwp
, int *wstat
)
1954 struct thread_info
*saved_thread
;
1956 saved_thread
= current_thread
;
1957 current_thread
= get_lwp_thread (lwp
);
1960 || (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) != SIGTRAP
))
1961 && supports_fast_tracepoints ()
1962 && agent_loaded_p ())
1964 struct fast_tpoint_collect_status status
;
1968 debug_printf ("Checking whether LWP %ld needs to move out of the "
1970 lwpid_of (current_thread
));
1972 r
= linux_fast_tracepoint_collecting (lwp
, &status
);
1975 || (WSTOPSIG (*wstat
) != SIGILL
1976 && WSTOPSIG (*wstat
) != SIGFPE
1977 && WSTOPSIG (*wstat
) != SIGSEGV
1978 && WSTOPSIG (*wstat
) != SIGBUS
))
1980 lwp
->collecting_fast_tracepoint
= r
;
1984 if (r
== 1 && lwp
->exit_jump_pad_bkpt
== NULL
)
1986 /* Haven't executed the original instruction yet.
1987 Set breakpoint there, and wait till it's hit,
1988 then single-step until exiting the jump pad. */
1989 lwp
->exit_jump_pad_bkpt
1990 = set_breakpoint_at (status
.adjusted_insn_addr
, NULL
);
1994 debug_printf ("Checking whether LWP %ld needs to move out of "
1995 "the jump pad...it does\n",
1996 lwpid_of (current_thread
));
1997 current_thread
= saved_thread
;
2004 /* If we get a synchronous signal while collecting, *and*
2005 while executing the (relocated) original instruction,
2006 reset the PC to point at the tpoint address, before
2007 reporting to GDB. Otherwise, it's an IPA lib bug: just
2008 report the signal to GDB, and pray for the best. */
2010 lwp
->collecting_fast_tracepoint
= 0;
2013 && (status
.adjusted_insn_addr
<= lwp
->stop_pc
2014 && lwp
->stop_pc
< status
.adjusted_insn_addr_end
))
2017 struct regcache
*regcache
;
2019 /* The si_addr on a few signals references the address
2020 of the faulting instruction. Adjust that as
2022 if ((WSTOPSIG (*wstat
) == SIGILL
2023 || WSTOPSIG (*wstat
) == SIGFPE
2024 || WSTOPSIG (*wstat
) == SIGBUS
2025 || WSTOPSIG (*wstat
) == SIGSEGV
)
2026 && ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
2027 (PTRACE_TYPE_ARG3
) 0, &info
) == 0
2028 /* Final check just to make sure we don't clobber
2029 the siginfo of non-kernel-sent signals. */
2030 && (uintptr_t) info
.si_addr
== lwp
->stop_pc
)
2032 info
.si_addr
= (void *) (uintptr_t) status
.tpoint_addr
;
2033 ptrace (PTRACE_SETSIGINFO
, lwpid_of (current_thread
),
2034 (PTRACE_TYPE_ARG3
) 0, &info
);
2037 regcache
= get_thread_regcache (current_thread
, 1);
2038 (*the_low_target
.set_pc
) (regcache
, status
.tpoint_addr
);
2039 lwp
->stop_pc
= status
.tpoint_addr
;
2041 /* Cancel any fast tracepoint lock this thread was
2043 force_unlock_trace_buffer ();
2046 if (lwp
->exit_jump_pad_bkpt
!= NULL
)
2049 debug_printf ("Cancelling fast exit-jump-pad: removing bkpt. "
2050 "stopping all threads momentarily.\n");
2052 stop_all_lwps (1, lwp
);
2054 delete_breakpoint (lwp
->exit_jump_pad_bkpt
);
2055 lwp
->exit_jump_pad_bkpt
= NULL
;
2057 unstop_all_lwps (1, lwp
);
2059 gdb_assert (lwp
->suspended
>= 0);
2065 debug_printf ("Checking whether LWP %ld needs to move out of the "
2067 lwpid_of (current_thread
));
2069 current_thread
= saved_thread
;
2073 /* Enqueue one signal in the "signals to report later when out of the
2077 enqueue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
2079 struct pending_signals
*p_sig
;
2080 struct thread_info
*thread
= get_lwp_thread (lwp
);
2083 debug_printf ("Deferring signal %d for LWP %ld.\n",
2084 WSTOPSIG (*wstat
), lwpid_of (thread
));
2088 struct pending_signals
*sig
;
2090 for (sig
= lwp
->pending_signals_to_report
;
2093 debug_printf (" Already queued %d\n",
2096 debug_printf (" (no more currently queued signals)\n");
2099 /* Don't enqueue non-RT signals if they are already in the deferred
2100 queue. (SIGSTOP being the easiest signal to see ending up here
2102 if (WSTOPSIG (*wstat
) < __SIGRTMIN
)
2104 struct pending_signals
*sig
;
2106 for (sig
= lwp
->pending_signals_to_report
;
2110 if (sig
->signal
== WSTOPSIG (*wstat
))
2113 debug_printf ("Not requeuing already queued non-RT signal %d"
2122 p_sig
= XCNEW (struct pending_signals
);
2123 p_sig
->prev
= lwp
->pending_signals_to_report
;
2124 p_sig
->signal
= WSTOPSIG (*wstat
);
2126 ptrace (PTRACE_GETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
2129 lwp
->pending_signals_to_report
= p_sig
;
2132 /* Dequeue one signal from the "signals to report later when out of
2133 the jump pad" list. */
2136 dequeue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
2138 struct thread_info
*thread
= get_lwp_thread (lwp
);
2140 if (lwp
->pending_signals_to_report
!= NULL
)
2142 struct pending_signals
**p_sig
;
2144 p_sig
= &lwp
->pending_signals_to_report
;
2145 while ((*p_sig
)->prev
!= NULL
)
2146 p_sig
= &(*p_sig
)->prev
;
2148 *wstat
= W_STOPCODE ((*p_sig
)->signal
);
2149 if ((*p_sig
)->info
.si_signo
!= 0)
2150 ptrace (PTRACE_SETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
2156 debug_printf ("Reporting deferred signal %d for LWP %ld.\n",
2157 WSTOPSIG (*wstat
), lwpid_of (thread
));
2161 struct pending_signals
*sig
;
2163 for (sig
= lwp
->pending_signals_to_report
;
2166 debug_printf (" Still queued %d\n",
2169 debug_printf (" (no more queued signals)\n");
2178 /* Fetch the possibly triggered data watchpoint info and store it in
2181 On some archs, like x86, that use debug registers to set
2182 watchpoints, it's possible that the way to know which watched
2183 address trapped, is to check the register that is used to select
2184 which address to watch. Problem is, between setting the watchpoint
2185 and reading back which data address trapped, the user may change
2186 the set of watchpoints, and, as a consequence, GDB changes the
2187 debug registers in the inferior. To avoid reading back a stale
2188 stopped-data-address when that happens, we cache in LP the fact
2189 that a watchpoint trapped, and the corresponding data address, as
2190 soon as we see CHILD stop with a SIGTRAP. If GDB changes the debug
2191 registers meanwhile, we have the cached data we can rely on. */
2194 check_stopped_by_watchpoint (struct lwp_info
*child
)
2196 if (the_low_target
.stopped_by_watchpoint
!= NULL
)
2198 struct thread_info
*saved_thread
;
2200 saved_thread
= current_thread
;
2201 current_thread
= get_lwp_thread (child
);
2203 if (the_low_target
.stopped_by_watchpoint ())
2205 child
->stop_reason
= TARGET_STOPPED_BY_WATCHPOINT
;
2207 if (the_low_target
.stopped_data_address
!= NULL
)
2208 child
->stopped_data_address
2209 = the_low_target
.stopped_data_address ();
2211 child
->stopped_data_address
= 0;
2214 current_thread
= saved_thread
;
2217 return child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
;
2220 /* Return the ptrace options that we want to try to enable. */
2223 linux_low_ptrace_options (int attached
)
2228 options
|= PTRACE_O_EXITKILL
;
2230 if (report_fork_events
)
2231 options
|= PTRACE_O_TRACEFORK
;
2233 if (report_vfork_events
)
2234 options
|= (PTRACE_O_TRACEVFORK
| PTRACE_O_TRACEVFORKDONE
);
2236 if (report_exec_events
)
2237 options
|= PTRACE_O_TRACEEXEC
;
2242 /* Do low-level handling of the event, and check if we should go on
2243 and pass it to caller code. Return the affected lwp if we are, or
2246 static struct lwp_info
*
2247 linux_low_filter_event (int lwpid
, int wstat
)
2249 struct lwp_info
*child
;
2250 struct thread_info
*thread
;
2251 int have_stop_pc
= 0;
2253 child
= find_lwp_pid (pid_to_ptid (lwpid
));
2255 /* Check for stop events reported by a process we didn't already
2256 know about - anything not already in our LWP list.
2258 If we're expecting to receive stopped processes after
2259 fork, vfork, and clone events, then we'll just add the
2260 new one to our list and go back to waiting for the event
2261 to be reported - the stopped process might be returned
2262 from waitpid before or after the event is.
2264 But note the case of a non-leader thread exec'ing after the
2265 leader having exited, and gone from our lists (because
2266 check_zombie_leaders deleted it). The non-leader thread
2267 changes its tid to the tgid. */
2269 if (WIFSTOPPED (wstat
) && child
== NULL
&& WSTOPSIG (wstat
) == SIGTRAP
2270 && linux_ptrace_get_extended_event (wstat
) == PTRACE_EVENT_EXEC
)
2274 /* A multi-thread exec after we had seen the leader exiting. */
2277 debug_printf ("LLW: Re-adding thread group leader LWP %d"
2278 "after exec.\n", lwpid
);
2281 child_ptid
= ptid_build (lwpid
, lwpid
, 0);
2282 child
= add_lwp (child_ptid
);
2284 current_thread
= child
->thread
;
2287 /* If we didn't find a process, one of two things presumably happened:
2288 - A process we started and then detached from has exited. Ignore it.
2289 - A process we are controlling has forked and the new child's stop
2290 was reported to us by the kernel. Save its PID. */
2291 if (child
== NULL
&& WIFSTOPPED (wstat
))
2293 add_to_pid_list (&stopped_pids
, lwpid
, wstat
);
2296 else if (child
== NULL
)
2299 thread
= get_lwp_thread (child
);
2303 child
->last_status
= wstat
;
2305 /* Check if the thread has exited. */
2306 if ((WIFEXITED (wstat
) || WIFSIGNALED (wstat
)))
2309 debug_printf ("LLFE: %d exited.\n", lwpid
);
2310 /* If there is at least one more LWP, then the exit signal was
2311 not the end of the debugged application and should be
2312 ignored, unless GDB wants to hear about thread exits. */
2313 if (report_thread_events
2314 || last_thread_of_process_p (pid_of (thread
)))
2316 /* Since events are serialized to GDB core, and we can't
2317 report this one right now. Leave the status pending for
2318 the next time we're able to report it. */
2319 mark_lwp_dead (child
, wstat
);
2329 gdb_assert (WIFSTOPPED (wstat
));
2331 if (WIFSTOPPED (wstat
))
2333 struct process_info
*proc
;
2335 /* Architecture-specific setup after inferior is running. */
2336 proc
= find_process_pid (pid_of (thread
));
2337 if (proc
->tdesc
== NULL
)
2341 /* This needs to happen after we have attached to the
2342 inferior and it is stopped for the first time, but
2343 before we access any inferior registers. */
2344 linux_arch_setup_thread (thread
);
2348 /* The process is started, but GDBserver will do
2349 architecture-specific setup after the program stops at
2350 the first instruction. */
2351 child
->status_pending_p
= 1;
2352 child
->status_pending
= wstat
;
2358 if (WIFSTOPPED (wstat
) && child
->must_set_ptrace_flags
)
2360 struct process_info
*proc
= find_process_pid (pid_of (thread
));
2361 int options
= linux_low_ptrace_options (proc
->attached
);
2363 linux_enable_event_reporting (lwpid
, options
);
2364 child
->must_set_ptrace_flags
= 0;
2367 /* Be careful to not overwrite stop_pc until
2368 check_stopped_by_breakpoint is called. */
2369 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGTRAP
2370 && linux_is_extended_waitstatus (wstat
))
2372 child
->stop_pc
= get_pc (child
);
2373 if (handle_extended_wait (&child
, wstat
))
2375 /* The event has been handled, so just return without
2381 /* Check first whether this was a SW/HW breakpoint before checking
2382 watchpoints, because at least s390 can't tell the data address of
2383 hardware watchpoint hits, and returns stopped-by-watchpoint as
2384 long as there's a watchpoint set. */
2385 if (WIFSTOPPED (wstat
) && linux_wstatus_maybe_breakpoint (wstat
))
2387 if (check_stopped_by_breakpoint (child
))
2391 /* Note that TRAP_HWBKPT can indicate either a hardware breakpoint
2392 or hardware watchpoint. Check which is which if we got
2393 TARGET_STOPPED_BY_HW_BREAKPOINT. Likewise, we may have single
2394 stepped an instruction that triggered a watchpoint. In that
2395 case, on some architectures (such as x86), instead of
2396 TRAP_HWBKPT, si_code indicates TRAP_TRACE, and we need to check
2397 the debug registers separately. */
2398 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGTRAP
2399 && child
->stop_reason
!= TARGET_STOPPED_BY_SW_BREAKPOINT
)
2400 check_stopped_by_watchpoint (child
);
2403 child
->stop_pc
= get_pc (child
);
2405 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGSTOP
2406 && child
->stop_expected
)
2409 debug_printf ("Expected stop.\n");
2410 child
->stop_expected
= 0;
2412 if (thread
->last_resume_kind
== resume_stop
)
2414 /* We want to report the stop to the core. Treat the
2415 SIGSTOP as a normal event. */
2417 debug_printf ("LLW: resume_stop SIGSTOP caught for %s.\n",
2418 target_pid_to_str (ptid_of (thread
)));
2420 else if (stopping_threads
!= NOT_STOPPING_THREADS
)
2422 /* Stopping threads. We don't want this SIGSTOP to end up
2425 debug_printf ("LLW: SIGSTOP caught for %s "
2426 "while stopping threads.\n",
2427 target_pid_to_str (ptid_of (thread
)));
2432 /* This is a delayed SIGSTOP. Filter out the event. */
2434 debug_printf ("LLW: %s %s, 0, 0 (discard delayed SIGSTOP)\n",
2435 child
->stepping
? "step" : "continue",
2436 target_pid_to_str (ptid_of (thread
)));
2438 linux_resume_one_lwp (child
, child
->stepping
, 0, NULL
);
2443 child
->status_pending_p
= 1;
2444 child
->status_pending
= wstat
;
2448 /* Resume LWPs that are currently stopped without any pending status
2449 to report, but are resumed from the core's perspective. */
2452 resume_stopped_resumed_lwps (struct inferior_list_entry
*entry
)
2454 struct thread_info
*thread
= (struct thread_info
*) entry
;
2455 struct lwp_info
*lp
= get_thread_lwp (thread
);
2459 && !lp
->status_pending_p
2460 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
)
2462 int step
= thread
->last_resume_kind
== resume_step
;
2465 debug_printf ("RSRL: resuming stopped-resumed LWP %s at %s: step=%d\n",
2466 target_pid_to_str (ptid_of (thread
)),
2467 paddress (lp
->stop_pc
),
2470 linux_resume_one_lwp (lp
, step
, GDB_SIGNAL_0
, NULL
);
2474 /* Wait for an event from child(ren) WAIT_PTID, and return any that
2475 match FILTER_PTID (leaving others pending). The PTIDs can be:
2476 minus_one_ptid, to specify any child; a pid PTID, specifying all
2477 lwps of a thread group; or a PTID representing a single lwp. Store
2478 the stop status through the status pointer WSTAT. OPTIONS is
2479 passed to the waitpid call. Return 0 if no event was found and
2480 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
2481 was found. Return the PID of the stopped child otherwise. */
2484 linux_wait_for_event_filtered (ptid_t wait_ptid
, ptid_t filter_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 (ptid_equal (filter_ptid
, minus_one_ptid
) || ptid_is_pid (filter_ptid
))
2502 event_thread
= (struct thread_info
*)
2503 find_inferior (&all_threads
, status_pending_p_callback
, &filter_ptid
);
2504 if (event_thread
!= NULL
)
2505 event_child
= get_thread_lwp (event_thread
);
2506 if (debug_threads
&& event_thread
)
2507 debug_printf ("Got a pending child %ld\n", lwpid_of (event_thread
));
2509 else if (!ptid_equal (filter_ptid
, null_ptid
))
2511 requested_child
= find_lwp_pid (filter_ptid
);
2513 if (stopping_threads
== NOT_STOPPING_THREADS
2514 && requested_child
->status_pending_p
2515 && requested_child
->collecting_fast_tracepoint
)
2517 enqueue_one_deferred_signal (requested_child
,
2518 &requested_child
->status_pending
);
2519 requested_child
->status_pending_p
= 0;
2520 requested_child
->status_pending
= 0;
2521 linux_resume_one_lwp (requested_child
, 0, 0, NULL
);
2524 if (requested_child
->suspended
2525 && requested_child
->status_pending_p
)
2527 internal_error (__FILE__
, __LINE__
,
2528 "requesting an event out of a"
2529 " suspended child?");
2532 if (requested_child
->status_pending_p
)
2534 event_child
= requested_child
;
2535 event_thread
= get_lwp_thread (event_child
);
2539 if (event_child
!= NULL
)
2542 debug_printf ("Got an event from pending child %ld (%04x)\n",
2543 lwpid_of (event_thread
), event_child
->status_pending
);
2544 *wstatp
= event_child
->status_pending
;
2545 event_child
->status_pending_p
= 0;
2546 event_child
->status_pending
= 0;
2547 current_thread
= event_thread
;
2548 return lwpid_of (event_thread
);
2551 /* But if we don't find a pending event, we'll have to wait.
2553 We only enter this loop if no process has a pending wait status.
2554 Thus any action taken in response to a wait status inside this
2555 loop is responding as soon as we detect the status, not after any
2558 /* Make sure SIGCHLD is blocked until the sigsuspend below. Block
2559 all signals while here. */
2560 sigfillset (&block_mask
);
2561 sigprocmask (SIG_BLOCK
, &block_mask
, &prev_mask
);
2563 /* Always pull all events out of the kernel. We'll randomly select
2564 an event LWP out of all that have events, to prevent
2566 while (event_child
== NULL
)
2570 /* Always use -1 and WNOHANG, due to couple of a kernel/ptrace
2573 - If the thread group leader exits while other threads in the
2574 thread group still exist, waitpid(TGID, ...) hangs. That
2575 waitpid won't return an exit status until the other threads
2576 in the group are reaped.
2578 - When a non-leader thread execs, that thread just vanishes
2579 without reporting an exit (so we'd hang if we waited for it
2580 explicitly in that case). The exec event is reported to
2583 ret
= my_waitpid (-1, wstatp
, options
| WNOHANG
);
2586 debug_printf ("LWFE: waitpid(-1, ...) returned %d, %s\n",
2587 ret
, errno
? strerror (errno
) : "ERRNO-OK");
2593 debug_printf ("LLW: waitpid %ld received %s\n",
2594 (long) ret
, status_to_str (*wstatp
));
2597 /* Filter all events. IOW, leave all events pending. We'll
2598 randomly select an event LWP out of all that have events
2600 linux_low_filter_event (ret
, *wstatp
);
2601 /* Retry until nothing comes out of waitpid. A single
2602 SIGCHLD can indicate more than one child stopped. */
2606 /* Now that we've pulled all events out of the kernel, resume
2607 LWPs that don't have an interesting event to report. */
2608 if (stopping_threads
== NOT_STOPPING_THREADS
)
2609 for_each_inferior (&all_threads
, resume_stopped_resumed_lwps
);
2611 /* ... and find an LWP with a status to report to the core, if
2613 event_thread
= (struct thread_info
*)
2614 find_inferior (&all_threads
, status_pending_p_callback
, &filter_ptid
);
2615 if (event_thread
!= NULL
)
2617 event_child
= get_thread_lwp (event_thread
);
2618 *wstatp
= event_child
->status_pending
;
2619 event_child
->status_pending_p
= 0;
2620 event_child
->status_pending
= 0;
2624 /* Check for zombie thread group leaders. Those can't be reaped
2625 until all other threads in the thread group are. */
2626 check_zombie_leaders ();
2628 /* If there are no resumed children left in the set of LWPs we
2629 want to wait for, bail. We can't just block in
2630 waitpid/sigsuspend, because lwps might have been left stopped
2631 in trace-stop state, and we'd be stuck forever waiting for
2632 their status to change (which would only happen if we resumed
2633 them). Even if WNOHANG is set, this return code is preferred
2634 over 0 (below), as it is more detailed. */
2635 if ((find_inferior (&all_threads
,
2636 not_stopped_callback
,
2637 &wait_ptid
) == NULL
))
2640 debug_printf ("LLW: exit (no unwaited-for LWP)\n");
2641 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2645 /* No interesting event to report to the caller. */
2646 if ((options
& WNOHANG
))
2649 debug_printf ("WNOHANG set, no event found\n");
2651 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2655 /* Block until we get an event reported with SIGCHLD. */
2657 debug_printf ("sigsuspend'ing\n");
2659 sigsuspend (&prev_mask
);
2660 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2664 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2666 current_thread
= event_thread
;
2668 return lwpid_of (event_thread
);
2671 /* Wait for an event from child(ren) PTID. PTIDs can be:
2672 minus_one_ptid, to specify any child; a pid PTID, specifying all
2673 lwps of a thread group; or a PTID representing a single lwp. Store
2674 the stop status through the status pointer WSTAT. OPTIONS is
2675 passed to the waitpid call. Return 0 if no event was found and
2676 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
2677 was found. Return the PID of the stopped child otherwise. */
2680 linux_wait_for_event (ptid_t ptid
, int *wstatp
, int options
)
2682 return linux_wait_for_event_filtered (ptid
, ptid
, wstatp
, options
);
2685 /* Count the LWP's that have had events. */
2688 count_events_callback (struct inferior_list_entry
*entry
, void *data
)
2690 struct thread_info
*thread
= (struct thread_info
*) entry
;
2691 struct lwp_info
*lp
= get_thread_lwp (thread
);
2692 int *count
= (int *) data
;
2694 gdb_assert (count
!= NULL
);
2696 /* Count only resumed LWPs that have an event pending. */
2697 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2698 && lp
->status_pending_p
)
2704 /* Select the LWP (if any) that is currently being single-stepped. */
2707 select_singlestep_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
2709 struct thread_info
*thread
= (struct thread_info
*) entry
;
2710 struct lwp_info
*lp
= get_thread_lwp (thread
);
2712 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2713 && thread
->last_resume_kind
== resume_step
2714 && lp
->status_pending_p
)
2720 /* Select the Nth LWP that has had an event. */
2723 select_event_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
2725 struct thread_info
*thread
= (struct thread_info
*) entry
;
2726 struct lwp_info
*lp
= get_thread_lwp (thread
);
2727 int *selector
= (int *) data
;
2729 gdb_assert (selector
!= NULL
);
2731 /* Select only resumed LWPs that have an event pending. */
2732 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2733 && lp
->status_pending_p
)
2734 if ((*selector
)-- == 0)
2740 /* Select one LWP out of those that have events pending. */
2743 select_event_lwp (struct lwp_info
**orig_lp
)
2746 int random_selector
;
2747 struct thread_info
*event_thread
= NULL
;
2749 /* In all-stop, give preference to the LWP that is being
2750 single-stepped. There will be at most one, and it's the LWP that
2751 the core is most interested in. If we didn't do this, then we'd
2752 have to handle pending step SIGTRAPs somehow in case the core
2753 later continues the previously-stepped thread, otherwise we'd
2754 report the pending SIGTRAP, and the core, not having stepped the
2755 thread, wouldn't understand what the trap was for, and therefore
2756 would report it to the user as a random signal. */
2760 = (struct thread_info
*) find_inferior (&all_threads
,
2761 select_singlestep_lwp_callback
,
2763 if (event_thread
!= NULL
)
2766 debug_printf ("SEL: Select single-step %s\n",
2767 target_pid_to_str (ptid_of (event_thread
)));
2770 if (event_thread
== NULL
)
2772 /* No single-stepping LWP. Select one at random, out of those
2773 which have had events. */
2775 /* First see how many events we have. */
2776 find_inferior (&all_threads
, count_events_callback
, &num_events
);
2777 gdb_assert (num_events
> 0);
2779 /* Now randomly pick a LWP out of those that have had
2781 random_selector
= (int)
2782 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
2784 if (debug_threads
&& num_events
> 1)
2785 debug_printf ("SEL: Found %d SIGTRAP events, selecting #%d\n",
2786 num_events
, random_selector
);
2789 = (struct thread_info
*) find_inferior (&all_threads
,
2790 select_event_lwp_callback
,
2794 if (event_thread
!= NULL
)
2796 struct lwp_info
*event_lp
= get_thread_lwp (event_thread
);
2798 /* Switch the event LWP. */
2799 *orig_lp
= event_lp
;
2803 /* Decrement the suspend count of an LWP. */
2806 unsuspend_one_lwp (struct inferior_list_entry
*entry
, void *except
)
2808 struct thread_info
*thread
= (struct thread_info
*) entry
;
2809 struct lwp_info
*lwp
= get_thread_lwp (thread
);
2811 /* Ignore EXCEPT. */
2815 lwp_suspended_decr (lwp
);
2819 /* Decrement the suspend count of all LWPs, except EXCEPT, if non
2823 unsuspend_all_lwps (struct lwp_info
*except
)
2825 find_inferior (&all_threads
, unsuspend_one_lwp
, except
);
2828 static void move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
);
2829 static int stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
,
2831 static int lwp_running (struct inferior_list_entry
*entry
, void *data
);
2832 static ptid_t
linux_wait_1 (ptid_t ptid
,
2833 struct target_waitstatus
*ourstatus
,
2834 int target_options
);
2836 /* Stabilize threads (move out of jump pads).
2838 If a thread is midway collecting a fast tracepoint, we need to
2839 finish the collection and move it out of the jump pad before
2840 reporting the signal.
2842 This avoids recursion while collecting (when a signal arrives
2843 midway, and the signal handler itself collects), which would trash
2844 the trace buffer. In case the user set a breakpoint in a signal
2845 handler, this avoids the backtrace showing the jump pad, etc..
2846 Most importantly, there are certain things we can't do safely if
2847 threads are stopped in a jump pad (or in its callee's). For
2850 - starting a new trace run. A thread still collecting the
2851 previous run, could trash the trace buffer when resumed. The trace
2852 buffer control structures would have been reset but the thread had
2853 no way to tell. The thread could even midway memcpy'ing to the
2854 buffer, which would mean that when resumed, it would clobber the
2855 trace buffer that had been set for a new run.
2857 - we can't rewrite/reuse the jump pads for new tracepoints
2858 safely. Say you do tstart while a thread is stopped midway while
2859 collecting. When the thread is later resumed, it finishes the
2860 collection, and returns to the jump pad, to execute the original
2861 instruction that was under the tracepoint jump at the time the
2862 older run had been started. If the jump pad had been rewritten
2863 since for something else in the new run, the thread would now
2864 execute the wrong / random instructions. */
2867 linux_stabilize_threads (void)
2869 struct thread_info
*saved_thread
;
2870 struct thread_info
*thread_stuck
;
2873 = (struct thread_info
*) find_inferior (&all_threads
,
2874 stuck_in_jump_pad_callback
,
2876 if (thread_stuck
!= NULL
)
2879 debug_printf ("can't stabilize, LWP %ld is stuck in jump pad\n",
2880 lwpid_of (thread_stuck
));
2884 saved_thread
= current_thread
;
2886 stabilizing_threads
= 1;
2889 for_each_inferior (&all_threads
, move_out_of_jump_pad_callback
);
2891 /* Loop until all are stopped out of the jump pads. */
2892 while (find_inferior (&all_threads
, lwp_running
, NULL
) != NULL
)
2894 struct target_waitstatus ourstatus
;
2895 struct lwp_info
*lwp
;
2898 /* Note that we go through the full wait even loop. While
2899 moving threads out of jump pad, we need to be able to step
2900 over internal breakpoints and such. */
2901 linux_wait_1 (minus_one_ptid
, &ourstatus
, 0);
2903 if (ourstatus
.kind
== TARGET_WAITKIND_STOPPED
)
2905 lwp
= get_thread_lwp (current_thread
);
2908 lwp_suspended_inc (lwp
);
2910 if (ourstatus
.value
.sig
!= GDB_SIGNAL_0
2911 || current_thread
->last_resume_kind
== resume_stop
)
2913 wstat
= W_STOPCODE (gdb_signal_to_host (ourstatus
.value
.sig
));
2914 enqueue_one_deferred_signal (lwp
, &wstat
);
2919 find_inferior (&all_threads
, unsuspend_one_lwp
, NULL
);
2921 stabilizing_threads
= 0;
2923 current_thread
= saved_thread
;
2928 = (struct thread_info
*) find_inferior (&all_threads
,
2929 stuck_in_jump_pad_callback
,
2931 if (thread_stuck
!= NULL
)
2932 debug_printf ("couldn't stabilize, LWP %ld got stuck in jump pad\n",
2933 lwpid_of (thread_stuck
));
2937 /* Convenience function that is called when the kernel reports an
2938 event that is not passed out to GDB. */
2941 ignore_event (struct target_waitstatus
*ourstatus
)
2943 /* If we got an event, there may still be others, as a single
2944 SIGCHLD can indicate more than one child stopped. This forces
2945 another target_wait call. */
2948 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2952 /* Convenience function that is called when the kernel reports an exit
2953 event. This decides whether to report the event to GDB as a
2954 process exit event, a thread exit event, or to suppress the
2958 filter_exit_event (struct lwp_info
*event_child
,
2959 struct target_waitstatus
*ourstatus
)
2961 struct thread_info
*thread
= get_lwp_thread (event_child
);
2962 ptid_t ptid
= ptid_of (thread
);
2964 if (!last_thread_of_process_p (pid_of (thread
)))
2966 if (report_thread_events
)
2967 ourstatus
->kind
= TARGET_WAITKIND_THREAD_EXITED
;
2969 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2971 delete_lwp (event_child
);
2976 /* Wait for process, returns status. */
2979 linux_wait_1 (ptid_t ptid
,
2980 struct target_waitstatus
*ourstatus
, int target_options
)
2983 struct lwp_info
*event_child
;
2986 int step_over_finished
;
2987 int bp_explains_trap
;
2988 int maybe_internal_trap
;
2997 debug_printf ("linux_wait_1: [%s]\n", target_pid_to_str (ptid
));
3000 /* Translate generic target options into linux options. */
3002 if (target_options
& TARGET_WNOHANG
)
3005 bp_explains_trap
= 0;
3008 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3010 /* Find a resumed LWP, if any. */
3011 if (find_inferior (&all_threads
,
3012 status_pending_p_callback
,
3013 &minus_one_ptid
) != NULL
)
3015 else if ((find_inferior (&all_threads
,
3016 not_stopped_callback
,
3017 &minus_one_ptid
) != NULL
))
3022 if (ptid_equal (step_over_bkpt
, null_ptid
))
3023 pid
= linux_wait_for_event (ptid
, &w
, options
);
3027 debug_printf ("step_over_bkpt set [%s], doing a blocking wait\n",
3028 target_pid_to_str (step_over_bkpt
));
3029 pid
= linux_wait_for_event (step_over_bkpt
, &w
, options
& ~WNOHANG
);
3032 if (pid
== 0 || (pid
== -1 && !any_resumed
))
3034 gdb_assert (target_options
& TARGET_WNOHANG
);
3038 debug_printf ("linux_wait_1 ret = null_ptid, "
3039 "TARGET_WAITKIND_IGNORE\n");
3043 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3050 debug_printf ("linux_wait_1 ret = null_ptid, "
3051 "TARGET_WAITKIND_NO_RESUMED\n");
3055 ourstatus
->kind
= TARGET_WAITKIND_NO_RESUMED
;
3059 event_child
= get_thread_lwp (current_thread
);
3061 /* linux_wait_for_event only returns an exit status for the last
3062 child of a process. Report it. */
3063 if (WIFEXITED (w
) || WIFSIGNALED (w
))
3067 ourstatus
->kind
= TARGET_WAITKIND_EXITED
;
3068 ourstatus
->value
.integer
= WEXITSTATUS (w
);
3072 debug_printf ("linux_wait_1 ret = %s, exited with "
3074 target_pid_to_str (ptid_of (current_thread
)),
3081 ourstatus
->kind
= TARGET_WAITKIND_SIGNALLED
;
3082 ourstatus
->value
.sig
= gdb_signal_from_host (WTERMSIG (w
));
3086 debug_printf ("linux_wait_1 ret = %s, terminated with "
3088 target_pid_to_str (ptid_of (current_thread
)),
3094 if (ourstatus
->kind
== TARGET_WAITKIND_EXITED
)
3095 return filter_exit_event (event_child
, ourstatus
);
3097 return ptid_of (current_thread
);
3100 /* If step-over executes a breakpoint instruction, in the case of a
3101 hardware single step it means a gdb/gdbserver breakpoint had been
3102 planted on top of a permanent breakpoint, in the case of a software
3103 single step it may just mean that gdbserver hit the reinsert breakpoint.
3104 The PC has been adjusted by check_stopped_by_breakpoint to point at
3105 the breakpoint address.
3106 So in the case of the hardware single step advance the PC manually
3107 past the breakpoint and in the case of software single step advance only
3108 if it's not the reinsert_breakpoint we are hitting.
3109 This avoids that a program would keep trapping a permanent breakpoint
3111 if (!ptid_equal (step_over_bkpt
, null_ptid
)
3112 && event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3113 && (event_child
->stepping
3114 || !reinsert_breakpoint_inserted_here (event_child
->stop_pc
)))
3116 int increment_pc
= 0;
3117 int breakpoint_kind
= 0;
3118 CORE_ADDR stop_pc
= event_child
->stop_pc
;
3121 the_target
->breakpoint_kind_from_current_state (&stop_pc
);
3122 the_target
->sw_breakpoint_from_kind (breakpoint_kind
, &increment_pc
);
3126 debug_printf ("step-over for %s executed software breakpoint\n",
3127 target_pid_to_str (ptid_of (current_thread
)));
3130 if (increment_pc
!= 0)
3132 struct regcache
*regcache
3133 = get_thread_regcache (current_thread
, 1);
3135 event_child
->stop_pc
+= increment_pc
;
3136 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
3138 if (!(*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))
3139 event_child
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3143 /* If this event was not handled before, and is not a SIGTRAP, we
3144 report it. SIGILL and SIGSEGV are also treated as traps in case
3145 a breakpoint is inserted at the current PC. If this target does
3146 not support internal breakpoints at all, we also report the
3147 SIGTRAP without further processing; it's of no concern to us. */
3149 = (supports_breakpoints ()
3150 && (WSTOPSIG (w
) == SIGTRAP
3151 || ((WSTOPSIG (w
) == SIGILL
3152 || WSTOPSIG (w
) == SIGSEGV
)
3153 && (*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))));
3155 if (maybe_internal_trap
)
3157 /* Handle anything that requires bookkeeping before deciding to
3158 report the event or continue waiting. */
3160 /* First check if we can explain the SIGTRAP with an internal
3161 breakpoint, or if we should possibly report the event to GDB.
3162 Do this before anything that may remove or insert a
3164 bp_explains_trap
= breakpoint_inserted_here (event_child
->stop_pc
);
3166 /* We have a SIGTRAP, possibly a step-over dance has just
3167 finished. If so, tweak the state machine accordingly,
3168 reinsert breakpoints and delete any reinsert (software
3169 single-step) breakpoints. */
3170 step_over_finished
= finish_step_over (event_child
);
3172 /* Now invoke the callbacks of any internal breakpoints there. */
3173 check_breakpoints (event_child
->stop_pc
);
3175 /* Handle tracepoint data collecting. This may overflow the
3176 trace buffer, and cause a tracing stop, removing
3178 trace_event
= handle_tracepoints (event_child
);
3180 if (bp_explains_trap
)
3182 /* If we stepped or ran into an internal breakpoint, we've
3183 already handled it. So next time we resume (from this
3184 PC), we should step over it. */
3186 debug_printf ("Hit a gdbserver breakpoint.\n");
3188 if (breakpoint_here (event_child
->stop_pc
))
3189 event_child
->need_step_over
= 1;
3194 /* We have some other signal, possibly a step-over dance was in
3195 progress, and it should be cancelled too. */
3196 step_over_finished
= finish_step_over (event_child
);
3199 /* We have all the data we need. Either report the event to GDB, or
3200 resume threads and keep waiting for more. */
3202 /* If we're collecting a fast tracepoint, finish the collection and
3203 move out of the jump pad before delivering a signal. See
3204 linux_stabilize_threads. */
3207 && WSTOPSIG (w
) != SIGTRAP
3208 && supports_fast_tracepoints ()
3209 && agent_loaded_p ())
3212 debug_printf ("Got signal %d for LWP %ld. Check if we need "
3213 "to defer or adjust it.\n",
3214 WSTOPSIG (w
), lwpid_of (current_thread
));
3216 /* Allow debugging the jump pad itself. */
3217 if (current_thread
->last_resume_kind
!= resume_step
3218 && maybe_move_out_of_jump_pad (event_child
, &w
))
3220 enqueue_one_deferred_signal (event_child
, &w
);
3223 debug_printf ("Signal %d for LWP %ld deferred (in jump pad)\n",
3224 WSTOPSIG (w
), lwpid_of (current_thread
));
3226 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
3228 return ignore_event (ourstatus
);
3232 if (event_child
->collecting_fast_tracepoint
)
3235 debug_printf ("LWP %ld was trying to move out of the jump pad (%d). "
3236 "Check if we're already there.\n",
3237 lwpid_of (current_thread
),
3238 event_child
->collecting_fast_tracepoint
);
3242 event_child
->collecting_fast_tracepoint
3243 = linux_fast_tracepoint_collecting (event_child
, NULL
);
3245 if (event_child
->collecting_fast_tracepoint
!= 1)
3247 /* No longer need this breakpoint. */
3248 if (event_child
->exit_jump_pad_bkpt
!= NULL
)
3251 debug_printf ("No longer need exit-jump-pad bkpt; removing it."
3252 "stopping all threads momentarily.\n");
3254 /* Other running threads could hit this breakpoint.
3255 We don't handle moribund locations like GDB does,
3256 instead we always pause all threads when removing
3257 breakpoints, so that any step-over or
3258 decr_pc_after_break adjustment is always taken
3259 care of while the breakpoint is still
3261 stop_all_lwps (1, event_child
);
3263 delete_breakpoint (event_child
->exit_jump_pad_bkpt
);
3264 event_child
->exit_jump_pad_bkpt
= NULL
;
3266 unstop_all_lwps (1, event_child
);
3268 gdb_assert (event_child
->suspended
>= 0);
3272 if (event_child
->collecting_fast_tracepoint
== 0)
3275 debug_printf ("fast tracepoint finished "
3276 "collecting successfully.\n");
3278 /* We may have a deferred signal to report. */
3279 if (dequeue_one_deferred_signal (event_child
, &w
))
3282 debug_printf ("dequeued one signal.\n");
3287 debug_printf ("no deferred signals.\n");
3289 if (stabilizing_threads
)
3291 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
3292 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
3296 debug_printf ("linux_wait_1 ret = %s, stopped "
3297 "while stabilizing threads\n",
3298 target_pid_to_str (ptid_of (current_thread
)));
3302 return ptid_of (current_thread
);
3308 /* Check whether GDB would be interested in this event. */
3310 /* If GDB is not interested in this signal, don't stop other
3311 threads, and don't report it to GDB. Just resume the inferior
3312 right away. We do this for threading-related signals as well as
3313 any that GDB specifically requested we ignore. But never ignore
3314 SIGSTOP if we sent it ourselves, and do not ignore signals when
3315 stepping - they may require special handling to skip the signal
3316 handler. Also never ignore signals that could be caused by a
3319 && current_thread
->last_resume_kind
!= resume_step
3321 #if defined (USE_THREAD_DB) && !defined (__ANDROID__)
3322 (current_process ()->priv
->thread_db
!= NULL
3323 && (WSTOPSIG (w
) == __SIGRTMIN
3324 || WSTOPSIG (w
) == __SIGRTMIN
+ 1))
3327 (pass_signals
[gdb_signal_from_host (WSTOPSIG (w
))]
3328 && !(WSTOPSIG (w
) == SIGSTOP
3329 && current_thread
->last_resume_kind
== resume_stop
)
3330 && !linux_wstatus_maybe_breakpoint (w
))))
3332 siginfo_t info
, *info_p
;
3335 debug_printf ("Ignored signal %d for LWP %ld.\n",
3336 WSTOPSIG (w
), lwpid_of (current_thread
));
3338 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
3339 (PTRACE_TYPE_ARG3
) 0, &info
) == 0)
3344 if (step_over_finished
)
3346 /* We cancelled this thread's step-over above. We still
3347 need to unsuspend all other LWPs, and set them back
3348 running again while the signal handler runs. */
3349 unsuspend_all_lwps (event_child
);
3351 /* Enqueue the pending signal info so that proceed_all_lwps
3353 enqueue_pending_signal (event_child
, WSTOPSIG (w
), info_p
);
3355 proceed_all_lwps ();
3359 linux_resume_one_lwp (event_child
, event_child
->stepping
,
3360 WSTOPSIG (w
), info_p
);
3362 return ignore_event (ourstatus
);
3365 /* Note that all addresses are always "out of the step range" when
3366 there's no range to begin with. */
3367 in_step_range
= lwp_in_step_range (event_child
);
3369 /* If GDB wanted this thread to single step, and the thread is out
3370 of the step range, we always want to report the SIGTRAP, and let
3371 GDB handle it. Watchpoints should always be reported. So should
3372 signals we can't explain. A SIGTRAP we can't explain could be a
3373 GDB breakpoint --- we may or not support Z0 breakpoints. If we
3374 do, we're be able to handle GDB breakpoints on top of internal
3375 breakpoints, by handling the internal breakpoint and still
3376 reporting the event to GDB. If we don't, we're out of luck, GDB
3377 won't see the breakpoint hit. If we see a single-step event but
3378 the thread should be continuing, don't pass the trap to gdb.
3379 That indicates that we had previously finished a single-step but
3380 left the single-step pending -- see
3381 complete_ongoing_step_over. */
3382 report_to_gdb
= (!maybe_internal_trap
3383 || (current_thread
->last_resume_kind
== resume_step
3385 || event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
3387 && !bp_explains_trap
3389 && !step_over_finished
3390 && !(current_thread
->last_resume_kind
== resume_continue
3391 && event_child
->stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
))
3392 || (gdb_breakpoint_here (event_child
->stop_pc
)
3393 && gdb_condition_true_at_breakpoint (event_child
->stop_pc
)
3394 && gdb_no_commands_at_breakpoint (event_child
->stop_pc
))
3395 || event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
);
3397 run_breakpoint_commands (event_child
->stop_pc
);
3399 /* We found no reason GDB would want us to stop. We either hit one
3400 of our own breakpoints, or finished an internal step GDB
3401 shouldn't know about. */
3406 if (bp_explains_trap
)
3407 debug_printf ("Hit a gdbserver breakpoint.\n");
3408 if (step_over_finished
)
3409 debug_printf ("Step-over finished.\n");
3411 debug_printf ("Tracepoint event.\n");
3412 if (lwp_in_step_range (event_child
))
3413 debug_printf ("Range stepping pc 0x%s [0x%s, 0x%s).\n",
3414 paddress (event_child
->stop_pc
),
3415 paddress (event_child
->step_range_start
),
3416 paddress (event_child
->step_range_end
));
3419 /* We're not reporting this breakpoint to GDB, so apply the
3420 decr_pc_after_break adjustment to the inferior's regcache
3423 if (the_low_target
.set_pc
!= NULL
)
3425 struct regcache
*regcache
3426 = get_thread_regcache (current_thread
, 1);
3427 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
3430 /* We may have finished stepping over a breakpoint. If so,
3431 we've stopped and suspended all LWPs momentarily except the
3432 stepping one. This is where we resume them all again. We're
3433 going to keep waiting, so use proceed, which handles stepping
3434 over the next breakpoint. */
3436 debug_printf ("proceeding all threads.\n");
3438 if (step_over_finished
)
3439 unsuspend_all_lwps (event_child
);
3441 proceed_all_lwps ();
3442 return ignore_event (ourstatus
);
3447 if (event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
3451 str
= target_waitstatus_to_string (&event_child
->waitstatus
);
3452 debug_printf ("LWP %ld: extended event with waitstatus %s\n",
3453 lwpid_of (get_lwp_thread (event_child
)), str
);
3456 if (current_thread
->last_resume_kind
== resume_step
)
3458 if (event_child
->step_range_start
== event_child
->step_range_end
)
3459 debug_printf ("GDB wanted to single-step, reporting event.\n");
3460 else if (!lwp_in_step_range (event_child
))
3461 debug_printf ("Out of step range, reporting event.\n");
3463 if (event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
)
3464 debug_printf ("Stopped by watchpoint.\n");
3465 else if (gdb_breakpoint_here (event_child
->stop_pc
))
3466 debug_printf ("Stopped by GDB breakpoint.\n");
3468 debug_printf ("Hit a non-gdbserver trap event.\n");
3471 /* Alright, we're going to report a stop. */
3473 if (!stabilizing_threads
)
3475 /* In all-stop, stop all threads. */
3477 stop_all_lwps (0, NULL
);
3479 /* If we're not waiting for a specific LWP, choose an event LWP
3480 from among those that have had events. Giving equal priority
3481 to all LWPs that have had events helps prevent
3483 if (ptid_equal (ptid
, minus_one_ptid
))
3485 event_child
->status_pending_p
= 1;
3486 event_child
->status_pending
= w
;
3488 select_event_lwp (&event_child
);
3490 /* current_thread and event_child must stay in sync. */
3491 current_thread
= get_lwp_thread (event_child
);
3493 event_child
->status_pending_p
= 0;
3494 w
= event_child
->status_pending
;
3497 if (step_over_finished
)
3501 /* If we were doing a step-over, all other threads but
3502 the stepping one had been paused in start_step_over,
3503 with their suspend counts incremented. We don't want
3504 to do a full unstop/unpause, because we're in
3505 all-stop mode (so we want threads stopped), but we
3506 still need to unsuspend the other threads, to
3507 decrement their `suspended' count back. */
3508 unsuspend_all_lwps (event_child
);
3512 /* If we just finished a step-over, then all threads had
3513 been momentarily paused. In all-stop, that's fine,
3514 we want threads stopped by now anyway. In non-stop,
3515 we need to re-resume threads that GDB wanted to be
3517 unstop_all_lwps (1, event_child
);
3521 /* Stabilize threads (move out of jump pads). */
3523 stabilize_threads ();
3527 /* If we just finished a step-over, then all threads had been
3528 momentarily paused. In all-stop, that's fine, we want
3529 threads stopped by now anyway. In non-stop, we need to
3530 re-resume threads that GDB wanted to be running. */
3531 if (step_over_finished
)
3532 unstop_all_lwps (1, event_child
);
3535 if (event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
3537 /* If the reported event is an exit, fork, vfork or exec, let
3539 *ourstatus
= event_child
->waitstatus
;
3540 /* Clear the event lwp's waitstatus since we handled it already. */
3541 event_child
->waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
3544 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
3546 /* Now that we've selected our final event LWP, un-adjust its PC if
3547 it was a software breakpoint, and the client doesn't know we can
3548 adjust the breakpoint ourselves. */
3549 if (event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3550 && !swbreak_feature
)
3552 int decr_pc
= the_low_target
.decr_pc_after_break
;
3556 struct regcache
*regcache
3557 = get_thread_regcache (current_thread
, 1);
3558 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
+ decr_pc
);
3562 if (current_thread
->last_resume_kind
== resume_stop
3563 && WSTOPSIG (w
) == SIGSTOP
)
3565 /* A thread that has been requested to stop by GDB with vCont;t,
3566 and it stopped cleanly, so report as SIG0. The use of
3567 SIGSTOP is an implementation detail. */
3568 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
3570 else if (current_thread
->last_resume_kind
== resume_stop
3571 && WSTOPSIG (w
) != SIGSTOP
)
3573 /* A thread that has been requested to stop by GDB with vCont;t,
3574 but, it stopped for other reasons. */
3575 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
3577 else if (ourstatus
->kind
== TARGET_WAITKIND_STOPPED
)
3579 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
3582 gdb_assert (ptid_equal (step_over_bkpt
, null_ptid
));
3586 debug_printf ("linux_wait_1 ret = %s, %d, %d\n",
3587 target_pid_to_str (ptid_of (current_thread
)),
3588 ourstatus
->kind
, ourstatus
->value
.sig
);
3592 if (ourstatus
->kind
== TARGET_WAITKIND_EXITED
)
3593 return filter_exit_event (event_child
, ourstatus
);
3595 return ptid_of (current_thread
);
3598 /* Get rid of any pending event in the pipe. */
3600 async_file_flush (void)
3606 ret
= read (linux_event_pipe
[0], &buf
, 1);
3607 while (ret
>= 0 || (ret
== -1 && errno
== EINTR
));
3610 /* Put something in the pipe, so the event loop wakes up. */
3612 async_file_mark (void)
3616 async_file_flush ();
3619 ret
= write (linux_event_pipe
[1], "+", 1);
3620 while (ret
== 0 || (ret
== -1 && errno
== EINTR
));
3622 /* Ignore EAGAIN. If the pipe is full, the event loop will already
3623 be awakened anyway. */
3627 linux_wait (ptid_t ptid
,
3628 struct target_waitstatus
*ourstatus
, int target_options
)
3632 /* Flush the async file first. */
3633 if (target_is_async_p ())
3634 async_file_flush ();
3638 event_ptid
= linux_wait_1 (ptid
, ourstatus
, target_options
);
3640 while ((target_options
& TARGET_WNOHANG
) == 0
3641 && ptid_equal (event_ptid
, null_ptid
)
3642 && ourstatus
->kind
== TARGET_WAITKIND_IGNORE
);
3644 /* If at least one stop was reported, there may be more. A single
3645 SIGCHLD can signal more than one child stop. */
3646 if (target_is_async_p ()
3647 && (target_options
& TARGET_WNOHANG
) != 0
3648 && !ptid_equal (event_ptid
, null_ptid
))
3654 /* Send a signal to an LWP. */
3657 kill_lwp (unsigned long lwpid
, int signo
)
3662 ret
= syscall (__NR_tkill
, lwpid
, signo
);
3663 if (errno
== ENOSYS
)
3665 /* If tkill fails, then we are not using nptl threads, a
3666 configuration we no longer support. */
3667 perror_with_name (("tkill"));
3673 linux_stop_lwp (struct lwp_info
*lwp
)
3679 send_sigstop (struct lwp_info
*lwp
)
3683 pid
= lwpid_of (get_lwp_thread (lwp
));
3685 /* If we already have a pending stop signal for this process, don't
3687 if (lwp
->stop_expected
)
3690 debug_printf ("Have pending sigstop for lwp %d\n", pid
);
3696 debug_printf ("Sending sigstop to lwp %d\n", pid
);
3698 lwp
->stop_expected
= 1;
3699 kill_lwp (pid
, SIGSTOP
);
3703 send_sigstop_callback (struct inferior_list_entry
*entry
, void *except
)
3705 struct thread_info
*thread
= (struct thread_info
*) entry
;
3706 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3708 /* Ignore EXCEPT. */
3719 /* Increment the suspend count of an LWP, and stop it, if not stopped
3722 suspend_and_send_sigstop_callback (struct inferior_list_entry
*entry
,
3725 struct thread_info
*thread
= (struct thread_info
*) entry
;
3726 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3728 /* Ignore EXCEPT. */
3732 lwp_suspended_inc (lwp
);
3734 return send_sigstop_callback (entry
, except
);
3738 mark_lwp_dead (struct lwp_info
*lwp
, int wstat
)
3740 /* Store the exit status for later. */
3741 lwp
->status_pending_p
= 1;
3742 lwp
->status_pending
= wstat
;
3744 /* Store in waitstatus as well, as there's nothing else to process
3746 if (WIFEXITED (wstat
))
3748 lwp
->waitstatus
.kind
= TARGET_WAITKIND_EXITED
;
3749 lwp
->waitstatus
.value
.integer
= WEXITSTATUS (wstat
);
3751 else if (WIFSIGNALED (wstat
))
3753 lwp
->waitstatus
.kind
= TARGET_WAITKIND_SIGNALLED
;
3754 lwp
->waitstatus
.value
.sig
= gdb_signal_from_host (WTERMSIG (wstat
));
3757 /* Prevent trying to stop it. */
3760 /* No further stops are expected from a dead lwp. */
3761 lwp
->stop_expected
= 0;
3764 /* Return true if LWP has exited already, and has a pending exit event
3765 to report to GDB. */
3768 lwp_is_marked_dead (struct lwp_info
*lwp
)
3770 return (lwp
->status_pending_p
3771 && (WIFEXITED (lwp
->status_pending
)
3772 || WIFSIGNALED (lwp
->status_pending
)));
3775 /* Wait for all children to stop for the SIGSTOPs we just queued. */
3778 wait_for_sigstop (void)
3780 struct thread_info
*saved_thread
;
3785 saved_thread
= current_thread
;
3786 if (saved_thread
!= NULL
)
3787 saved_tid
= saved_thread
->entry
.id
;
3789 saved_tid
= null_ptid
; /* avoid bogus unused warning */
3792 debug_printf ("wait_for_sigstop: pulling events\n");
3794 /* Passing NULL_PTID as filter indicates we want all events to be
3795 left pending. Eventually this returns when there are no
3796 unwaited-for children left. */
3797 ret
= linux_wait_for_event_filtered (minus_one_ptid
, null_ptid
,
3799 gdb_assert (ret
== -1);
3801 if (saved_thread
== NULL
|| linux_thread_alive (saved_tid
))
3802 current_thread
= saved_thread
;
3806 debug_printf ("Previously current thread died.\n");
3808 /* We can't change the current inferior behind GDB's back,
3809 otherwise, a subsequent command may apply to the wrong
3811 current_thread
= NULL
;
3815 /* Returns true if LWP ENTRY is stopped in a jump pad, and we can't
3816 move it out, because we need to report the stop event to GDB. For
3817 example, if the user puts a breakpoint in the jump pad, it's
3818 because she wants to debug it. */
3821 stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
, void *data
)
3823 struct thread_info
*thread
= (struct thread_info
*) entry
;
3824 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3826 if (lwp
->suspended
!= 0)
3828 internal_error (__FILE__
, __LINE__
,
3829 "LWP %ld is suspended, suspended=%d\n",
3830 lwpid_of (thread
), lwp
->suspended
);
3832 gdb_assert (lwp
->stopped
);
3834 /* Allow debugging the jump pad, gdb_collect, etc.. */
3835 return (supports_fast_tracepoints ()
3836 && agent_loaded_p ()
3837 && (gdb_breakpoint_here (lwp
->stop_pc
)
3838 || lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
3839 || thread
->last_resume_kind
== resume_step
)
3840 && linux_fast_tracepoint_collecting (lwp
, NULL
));
3844 move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
)
3846 struct thread_info
*thread
= (struct thread_info
*) entry
;
3847 struct thread_info
*saved_thread
;
3848 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3851 if (lwp
->suspended
!= 0)
3853 internal_error (__FILE__
, __LINE__
,
3854 "LWP %ld is suspended, suspended=%d\n",
3855 lwpid_of (thread
), lwp
->suspended
);
3857 gdb_assert (lwp
->stopped
);
3859 /* For gdb_breakpoint_here. */
3860 saved_thread
= current_thread
;
3861 current_thread
= thread
;
3863 wstat
= lwp
->status_pending_p
? &lwp
->status_pending
: NULL
;
3865 /* Allow debugging the jump pad, gdb_collect, etc. */
3866 if (!gdb_breakpoint_here (lwp
->stop_pc
)
3867 && lwp
->stop_reason
!= TARGET_STOPPED_BY_WATCHPOINT
3868 && thread
->last_resume_kind
!= resume_step
3869 && maybe_move_out_of_jump_pad (lwp
, wstat
))
3872 debug_printf ("LWP %ld needs stabilizing (in jump pad)\n",
3877 lwp
->status_pending_p
= 0;
3878 enqueue_one_deferred_signal (lwp
, wstat
);
3881 debug_printf ("Signal %d for LWP %ld deferred "
3883 WSTOPSIG (*wstat
), lwpid_of (thread
));
3886 linux_resume_one_lwp (lwp
, 0, 0, NULL
);
3889 lwp_suspended_inc (lwp
);
3891 current_thread
= saved_thread
;
3895 lwp_running (struct inferior_list_entry
*entry
, void *data
)
3897 struct thread_info
*thread
= (struct thread_info
*) entry
;
3898 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3900 if (lwp_is_marked_dead (lwp
))
3907 /* Stop all lwps that aren't stopped yet, except EXCEPT, if not NULL.
3908 If SUSPEND, then also increase the suspend count of every LWP,
3912 stop_all_lwps (int suspend
, struct lwp_info
*except
)
3914 /* Should not be called recursively. */
3915 gdb_assert (stopping_threads
== NOT_STOPPING_THREADS
);
3920 debug_printf ("stop_all_lwps (%s, except=%s)\n",
3921 suspend
? "stop-and-suspend" : "stop",
3923 ? target_pid_to_str (ptid_of (get_lwp_thread (except
)))
3927 stopping_threads
= (suspend
3928 ? STOPPING_AND_SUSPENDING_THREADS
3929 : STOPPING_THREADS
);
3932 find_inferior (&all_threads
, suspend_and_send_sigstop_callback
, except
);
3934 find_inferior (&all_threads
, send_sigstop_callback
, except
);
3935 wait_for_sigstop ();
3936 stopping_threads
= NOT_STOPPING_THREADS
;
3940 debug_printf ("stop_all_lwps done, setting stopping_threads "
3941 "back to !stopping\n");
3946 /* Enqueue one signal in the chain of signals which need to be
3947 delivered to this process on next resume. */
3950 enqueue_pending_signal (struct lwp_info
*lwp
, int signal
, siginfo_t
*info
)
3952 struct pending_signals
*p_sig
= XNEW (struct pending_signals
);
3954 p_sig
->prev
= lwp
->pending_signals
;
3955 p_sig
->signal
= signal
;
3957 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
3959 memcpy (&p_sig
->info
, info
, sizeof (siginfo_t
));
3960 lwp
->pending_signals
= p_sig
;
3963 /* Install breakpoints for software single stepping. */
3966 install_software_single_step_breakpoints (struct lwp_info
*lwp
)
3970 struct regcache
*regcache
= get_thread_regcache (current_thread
, 1);
3971 VEC (CORE_ADDR
) *next_pcs
= NULL
;
3972 struct cleanup
*old_chain
= make_cleanup (VEC_cleanup (CORE_ADDR
), &next_pcs
);
3975 next_pcs
= (*the_low_target
.get_next_pcs
) (pc
, regcache
);
3977 for (i
= 0; VEC_iterate (CORE_ADDR
, next_pcs
, i
, pc
); ++i
)
3978 set_reinsert_breakpoint (pc
);
3980 do_cleanups (old_chain
);
3983 /* Single step via hardware or software single step.
3984 Return 1 if hardware single stepping, 0 if software single stepping
3985 or can't single step. */
3988 single_step (struct lwp_info
* lwp
)
3992 if (can_hardware_single_step ())
3996 else if (can_software_single_step ())
3998 install_software_single_step_breakpoints (lwp
);
4004 debug_printf ("stepping is not implemented on this target");
4010 /* Resume execution of LWP. If STEP is nonzero, single-step it. If
4011 SIGNAL is nonzero, give it that signal. */
4014 linux_resume_one_lwp_throw (struct lwp_info
*lwp
,
4015 int step
, int signal
, siginfo_t
*info
)
4017 struct thread_info
*thread
= get_lwp_thread (lwp
);
4018 struct thread_info
*saved_thread
;
4019 int fast_tp_collecting
;
4020 struct process_info
*proc
= get_thread_process (thread
);
4022 /* Note that target description may not be initialised
4023 (proc->tdesc == NULL) at this point because the program hasn't
4024 stopped at the first instruction yet. It means GDBserver skips
4025 the extra traps from the wrapper program (see option --wrapper).
4026 Code in this function that requires register access should be
4027 guarded by proc->tdesc == NULL or something else. */
4029 if (lwp
->stopped
== 0)
4032 gdb_assert (lwp
->waitstatus
.kind
== TARGET_WAITKIND_IGNORE
);
4034 fast_tp_collecting
= lwp
->collecting_fast_tracepoint
;
4036 gdb_assert (!stabilizing_threads
|| fast_tp_collecting
);
4038 /* Cancel actions that rely on GDB not changing the PC (e.g., the
4039 user used the "jump" command, or "set $pc = foo"). */
4040 if (thread
->while_stepping
!= NULL
&& lwp
->stop_pc
!= get_pc (lwp
))
4042 /* Collecting 'while-stepping' actions doesn't make sense
4044 release_while_stepping_state_list (thread
);
4047 /* If we have pending signals or status, and a new signal, enqueue the
4048 signal. Also enqueue the signal if we are waiting to reinsert a
4049 breakpoint; it will be picked up again below. */
4051 && (lwp
->status_pending_p
4052 || lwp
->pending_signals
!= NULL
4053 || lwp
->bp_reinsert
!= 0
4054 || fast_tp_collecting
))
4056 struct pending_signals
*p_sig
= XNEW (struct pending_signals
);
4058 p_sig
->prev
= lwp
->pending_signals
;
4059 p_sig
->signal
= signal
;
4061 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
4063 memcpy (&p_sig
->info
, info
, sizeof (siginfo_t
));
4064 lwp
->pending_signals
= p_sig
;
4067 if (lwp
->status_pending_p
)
4070 debug_printf ("Not resuming lwp %ld (%s, signal %d, stop %s);"
4071 " has pending status\n",
4072 lwpid_of (thread
), step
? "step" : "continue", signal
,
4073 lwp
->stop_expected
? "expected" : "not expected");
4077 saved_thread
= current_thread
;
4078 current_thread
= thread
;
4081 debug_printf ("Resuming lwp %ld (%s, signal %d, stop %s)\n",
4082 lwpid_of (thread
), step
? "step" : "continue", signal
,
4083 lwp
->stop_expected
? "expected" : "not expected");
4085 /* This bit needs some thinking about. If we get a signal that
4086 we must report while a single-step reinsert is still pending,
4087 we often end up resuming the thread. It might be better to
4088 (ew) allow a stack of pending events; then we could be sure that
4089 the reinsert happened right away and not lose any signals.
4091 Making this stack would also shrink the window in which breakpoints are
4092 uninserted (see comment in linux_wait_for_lwp) but not enough for
4093 complete correctness, so it won't solve that problem. It may be
4094 worthwhile just to solve this one, however. */
4095 if (lwp
->bp_reinsert
!= 0)
4098 debug_printf (" pending reinsert at 0x%s\n",
4099 paddress (lwp
->bp_reinsert
));
4101 if (can_hardware_single_step ())
4103 if (fast_tp_collecting
== 0)
4106 fprintf (stderr
, "BAD - reinserting but not stepping.\n");
4108 fprintf (stderr
, "BAD - reinserting and suspended(%d).\n",
4115 /* Postpone any pending signal. It was enqueued above. */
4119 if (fast_tp_collecting
== 1)
4122 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
4123 " (exit-jump-pad-bkpt)\n",
4126 /* Postpone any pending signal. It was enqueued above. */
4129 else if (fast_tp_collecting
== 2)
4132 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
4133 " single-stepping\n",
4136 if (can_hardware_single_step ())
4140 internal_error (__FILE__
, __LINE__
,
4141 "moving out of jump pad single-stepping"
4142 " not implemented on this target");
4145 /* Postpone any pending signal. It was enqueued above. */
4149 /* If we have while-stepping actions in this thread set it stepping.
4150 If we have a signal to deliver, it may or may not be set to
4151 SIG_IGN, we don't know. Assume so, and allow collecting
4152 while-stepping into a signal handler. A possible smart thing to
4153 do would be to set an internal breakpoint at the signal return
4154 address, continue, and carry on catching this while-stepping
4155 action only when that breakpoint is hit. A future
4157 if (thread
->while_stepping
!= NULL
)
4160 debug_printf ("lwp %ld has a while-stepping action -> forcing step.\n",
4163 step
= single_step (lwp
);
4166 if (proc
->tdesc
!= NULL
&& the_low_target
.get_pc
!= NULL
)
4168 struct regcache
*regcache
= get_thread_regcache (current_thread
, 1);
4170 lwp
->stop_pc
= (*the_low_target
.get_pc
) (regcache
);
4174 debug_printf (" %s from pc 0x%lx\n", step
? "step" : "continue",
4175 (long) lwp
->stop_pc
);
4179 /* If we have pending signals, consume one unless we are trying to
4180 reinsert a breakpoint or we're trying to finish a fast tracepoint
4182 if (lwp
->pending_signals
!= NULL
4183 && lwp
->bp_reinsert
== 0
4184 && fast_tp_collecting
== 0)
4186 struct pending_signals
**p_sig
;
4188 p_sig
= &lwp
->pending_signals
;
4189 while ((*p_sig
)->prev
!= NULL
)
4190 p_sig
= &(*p_sig
)->prev
;
4192 signal
= (*p_sig
)->signal
;
4193 if ((*p_sig
)->info
.si_signo
!= 0)
4194 ptrace (PTRACE_SETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
4201 if (the_low_target
.prepare_to_resume
!= NULL
)
4202 the_low_target
.prepare_to_resume (lwp
);
4204 regcache_invalidate_thread (thread
);
4206 lwp
->stepping
= step
;
4207 ptrace (step
? PTRACE_SINGLESTEP
: PTRACE_CONT
, lwpid_of (thread
),
4208 (PTRACE_TYPE_ARG3
) 0,
4209 /* Coerce to a uintptr_t first to avoid potential gcc warning
4210 of coercing an 8 byte integer to a 4 byte pointer. */
4211 (PTRACE_TYPE_ARG4
) (uintptr_t) signal
);
4213 current_thread
= saved_thread
;
4215 perror_with_name ("resuming thread");
4217 /* Successfully resumed. Clear state that no longer makes sense,
4218 and mark the LWP as running. Must not do this before resuming
4219 otherwise if that fails other code will be confused. E.g., we'd
4220 later try to stop the LWP and hang forever waiting for a stop
4221 status. Note that we must not throw after this is cleared,
4222 otherwise handle_zombie_lwp_error would get confused. */
4224 lwp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
4227 /* Called when we try to resume a stopped LWP and that errors out. If
4228 the LWP is no longer in ptrace-stopped state (meaning it's zombie,
4229 or about to become), discard the error, clear any pending status
4230 the LWP may have, and return true (we'll collect the exit status
4231 soon enough). Otherwise, return false. */
4234 check_ptrace_stopped_lwp_gone (struct lwp_info
*lp
)
4236 struct thread_info
*thread
= get_lwp_thread (lp
);
4238 /* If we get an error after resuming the LWP successfully, we'd
4239 confuse !T state for the LWP being gone. */
4240 gdb_assert (lp
->stopped
);
4242 /* We can't just check whether the LWP is in 'Z (Zombie)' state,
4243 because even if ptrace failed with ESRCH, the tracee may be "not
4244 yet fully dead", but already refusing ptrace requests. In that
4245 case the tracee has 'R (Running)' state for a little bit
4246 (observed in Linux 3.18). See also the note on ESRCH in the
4247 ptrace(2) man page. Instead, check whether the LWP has any state
4248 other than ptrace-stopped. */
4250 /* Don't assume anything if /proc/PID/status can't be read. */
4251 if (linux_proc_pid_is_trace_stopped_nowarn (lwpid_of (thread
)) == 0)
4253 lp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
4254 lp
->status_pending_p
= 0;
4260 /* Like linux_resume_one_lwp_throw, but no error is thrown if the LWP
4261 disappears while we try to resume it. */
4264 linux_resume_one_lwp (struct lwp_info
*lwp
,
4265 int step
, int signal
, siginfo_t
*info
)
4269 linux_resume_one_lwp_throw (lwp
, step
, signal
, info
);
4271 CATCH (ex
, RETURN_MASK_ERROR
)
4273 if (!check_ptrace_stopped_lwp_gone (lwp
))
4274 throw_exception (ex
);
4279 struct thread_resume_array
4281 struct thread_resume
*resume
;
4285 /* This function is called once per thread via find_inferior.
4286 ARG is a pointer to a thread_resume_array struct.
4287 We look up the thread specified by ENTRY in ARG, and mark the thread
4288 with a pointer to the appropriate resume request.
4290 This algorithm is O(threads * resume elements), but resume elements
4291 is small (and will remain small at least until GDB supports thread
4295 linux_set_resume_request (struct inferior_list_entry
*entry
, void *arg
)
4297 struct thread_info
*thread
= (struct thread_info
*) entry
;
4298 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4300 struct thread_resume_array
*r
;
4302 r
= (struct thread_resume_array
*) arg
;
4304 for (ndx
= 0; ndx
< r
->n
; ndx
++)
4306 ptid_t ptid
= r
->resume
[ndx
].thread
;
4307 if (ptid_equal (ptid
, minus_one_ptid
)
4308 || ptid_equal (ptid
, entry
->id
)
4309 /* Handle both 'pPID' and 'pPID.-1' as meaning 'all threads
4311 || (ptid_get_pid (ptid
) == pid_of (thread
)
4312 && (ptid_is_pid (ptid
)
4313 || ptid_get_lwp (ptid
) == -1)))
4315 if (r
->resume
[ndx
].kind
== resume_stop
4316 && thread
->last_resume_kind
== resume_stop
)
4319 debug_printf ("already %s LWP %ld at GDB's request\n",
4320 (thread
->last_status
.kind
4321 == TARGET_WAITKIND_STOPPED
)
4329 lwp
->resume
= &r
->resume
[ndx
];
4330 thread
->last_resume_kind
= lwp
->resume
->kind
;
4332 lwp
->step_range_start
= lwp
->resume
->step_range_start
;
4333 lwp
->step_range_end
= lwp
->resume
->step_range_end
;
4335 /* If we had a deferred signal to report, dequeue one now.
4336 This can happen if LWP gets more than one signal while
4337 trying to get out of a jump pad. */
4339 && !lwp
->status_pending_p
4340 && dequeue_one_deferred_signal (lwp
, &lwp
->status_pending
))
4342 lwp
->status_pending_p
= 1;
4345 debug_printf ("Dequeueing deferred signal %d for LWP %ld, "
4346 "leaving status pending.\n",
4347 WSTOPSIG (lwp
->status_pending
),
4355 /* No resume action for this thread. */
4361 /* find_inferior callback for linux_resume.
4362 Set *FLAG_P if this lwp has an interesting status pending. */
4365 resume_status_pending_p (struct inferior_list_entry
*entry
, void *flag_p
)
4367 struct thread_info
*thread
= (struct thread_info
*) entry
;
4368 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4370 /* LWPs which will not be resumed are not interesting, because
4371 we might not wait for them next time through linux_wait. */
4372 if (lwp
->resume
== NULL
)
4375 if (thread_still_has_status_pending_p (thread
))
4376 * (int *) flag_p
= 1;
4381 /* Return 1 if this lwp that GDB wants running is stopped at an
4382 internal breakpoint that we need to step over. It assumes that any
4383 required STOP_PC adjustment has already been propagated to the
4384 inferior's regcache. */
4387 need_step_over_p (struct inferior_list_entry
*entry
, void *dummy
)
4389 struct thread_info
*thread
= (struct thread_info
*) entry
;
4390 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4391 struct thread_info
*saved_thread
;
4393 struct process_info
*proc
= get_thread_process (thread
);
4395 /* GDBserver is skipping the extra traps from the wrapper program,
4396 don't have to do step over. */
4397 if (proc
->tdesc
== NULL
)
4400 /* LWPs which will not be resumed are not interesting, because we
4401 might not wait for them next time through linux_wait. */
4406 debug_printf ("Need step over [LWP %ld]? Ignoring, not stopped\n",
4411 if (thread
->last_resume_kind
== resume_stop
)
4414 debug_printf ("Need step over [LWP %ld]? Ignoring, should remain"
4420 gdb_assert (lwp
->suspended
>= 0);
4425 debug_printf ("Need step over [LWP %ld]? Ignoring, suspended\n",
4430 if (!lwp
->need_step_over
)
4433 debug_printf ("Need step over [LWP %ld]? No\n", lwpid_of (thread
));
4436 if (lwp
->status_pending_p
)
4439 debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
4445 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
4449 /* If the PC has changed since we stopped, then don't do anything,
4450 and let the breakpoint/tracepoint be hit. This happens if, for
4451 instance, GDB handled the decr_pc_after_break subtraction itself,
4452 GDB is OOL stepping this thread, or the user has issued a "jump"
4453 command, or poked thread's registers herself. */
4454 if (pc
!= lwp
->stop_pc
)
4457 debug_printf ("Need step over [LWP %ld]? Cancelling, PC was changed. "
4458 "Old stop_pc was 0x%s, PC is now 0x%s\n",
4460 paddress (lwp
->stop_pc
), paddress (pc
));
4462 lwp
->need_step_over
= 0;
4466 saved_thread
= current_thread
;
4467 current_thread
= thread
;
4469 /* We can only step over breakpoints we know about. */
4470 if (breakpoint_here (pc
) || fast_tracepoint_jump_here (pc
))
4472 /* Don't step over a breakpoint that GDB expects to hit
4473 though. If the condition is being evaluated on the target's side
4474 and it evaluate to false, step over this breakpoint as well. */
4475 if (gdb_breakpoint_here (pc
)
4476 && gdb_condition_true_at_breakpoint (pc
)
4477 && gdb_no_commands_at_breakpoint (pc
))
4480 debug_printf ("Need step over [LWP %ld]? yes, but found"
4481 " GDB breakpoint at 0x%s; skipping step over\n",
4482 lwpid_of (thread
), paddress (pc
));
4484 current_thread
= saved_thread
;
4490 debug_printf ("Need step over [LWP %ld]? yes, "
4491 "found breakpoint at 0x%s\n",
4492 lwpid_of (thread
), paddress (pc
));
4494 /* We've found an lwp that needs stepping over --- return 1 so
4495 that find_inferior stops looking. */
4496 current_thread
= saved_thread
;
4498 /* If the step over is cancelled, this is set again. */
4499 lwp
->need_step_over
= 0;
4504 current_thread
= saved_thread
;
4507 debug_printf ("Need step over [LWP %ld]? No, no breakpoint found"
4509 lwpid_of (thread
), paddress (pc
));
4514 /* Start a step-over operation on LWP. When LWP stopped at a
4515 breakpoint, to make progress, we need to remove the breakpoint out
4516 of the way. If we let other threads run while we do that, they may
4517 pass by the breakpoint location and miss hitting it. To avoid
4518 that, a step-over momentarily stops all threads while LWP is
4519 single-stepped while the breakpoint is temporarily uninserted from
4520 the inferior. When the single-step finishes, we reinsert the
4521 breakpoint, and let all threads that are supposed to be running,
4524 On targets that don't support hardware single-step, we don't
4525 currently support full software single-stepping. Instead, we only
4526 support stepping over the thread event breakpoint, by asking the
4527 low target where to place a reinsert breakpoint. Since this
4528 routine assumes the breakpoint being stepped over is a thread event
4529 breakpoint, it usually assumes the return address of the current
4530 function is a good enough place to set the reinsert breakpoint. */
4533 start_step_over (struct lwp_info
*lwp
)
4535 struct thread_info
*thread
= get_lwp_thread (lwp
);
4536 struct thread_info
*saved_thread
;
4541 debug_printf ("Starting step-over on LWP %ld. Stopping all threads\n",
4544 stop_all_lwps (1, lwp
);
4546 if (lwp
->suspended
!= 0)
4548 internal_error (__FILE__
, __LINE__
,
4549 "LWP %ld suspended=%d\n", lwpid_of (thread
),
4554 debug_printf ("Done stopping all threads for step-over.\n");
4556 /* Note, we should always reach here with an already adjusted PC,
4557 either by GDB (if we're resuming due to GDB's request), or by our
4558 caller, if we just finished handling an internal breakpoint GDB
4559 shouldn't care about. */
4562 saved_thread
= current_thread
;
4563 current_thread
= thread
;
4565 lwp
->bp_reinsert
= pc
;
4566 uninsert_breakpoints_at (pc
);
4567 uninsert_fast_tracepoint_jumps_at (pc
);
4569 step
= single_step (lwp
);
4571 current_thread
= saved_thread
;
4573 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
4575 /* Require next event from this LWP. */
4576 step_over_bkpt
= thread
->entry
.id
;
4580 /* Finish a step-over. Reinsert the breakpoint we had uninserted in
4581 start_step_over, if still there, and delete any reinsert
4582 breakpoints we've set, on non hardware single-step targets. */
4585 finish_step_over (struct lwp_info
*lwp
)
4587 if (lwp
->bp_reinsert
!= 0)
4590 debug_printf ("Finished step over.\n");
4592 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
4593 may be no breakpoint to reinsert there by now. */
4594 reinsert_breakpoints_at (lwp
->bp_reinsert
);
4595 reinsert_fast_tracepoint_jumps_at (lwp
->bp_reinsert
);
4597 lwp
->bp_reinsert
= 0;
4599 /* Delete any software-single-step reinsert breakpoints. No
4600 longer needed. We don't have to worry about other threads
4601 hitting this trap, and later not being able to explain it,
4602 because we were stepping over a breakpoint, and we hold all
4603 threads but LWP stopped while doing that. */
4604 if (!can_hardware_single_step ())
4605 delete_reinsert_breakpoints ();
4607 step_over_bkpt
= null_ptid
;
4614 /* If there's a step over in progress, wait until all threads stop
4615 (that is, until the stepping thread finishes its step), and
4616 unsuspend all lwps. The stepping thread ends with its status
4617 pending, which is processed later when we get back to processing
4621 complete_ongoing_step_over (void)
4623 if (!ptid_equal (step_over_bkpt
, null_ptid
))
4625 struct lwp_info
*lwp
;
4630 debug_printf ("detach: step over in progress, finish it first\n");
4632 /* Passing NULL_PTID as filter indicates we want all events to
4633 be left pending. Eventually this returns when there are no
4634 unwaited-for children left. */
4635 ret
= linux_wait_for_event_filtered (minus_one_ptid
, null_ptid
,
4637 gdb_assert (ret
== -1);
4639 lwp
= find_lwp_pid (step_over_bkpt
);
4641 finish_step_over (lwp
);
4642 step_over_bkpt
= null_ptid
;
4643 unsuspend_all_lwps (lwp
);
4647 /* This function is called once per thread. We check the thread's resume
4648 request, which will tell us whether to resume, step, or leave the thread
4649 stopped; and what signal, if any, it should be sent.
4651 For threads which we aren't explicitly told otherwise, we preserve
4652 the stepping flag; this is used for stepping over gdbserver-placed
4655 If pending_flags was set in any thread, we queue any needed
4656 signals, since we won't actually resume. We already have a pending
4657 event to report, so we don't need to preserve any step requests;
4658 they should be re-issued if necessary. */
4661 linux_resume_one_thread (struct inferior_list_entry
*entry
, void *arg
)
4663 struct thread_info
*thread
= (struct thread_info
*) entry
;
4664 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4666 int leave_all_stopped
= * (int *) arg
;
4669 if (lwp
->resume
== NULL
)
4672 if (lwp
->resume
->kind
== resume_stop
)
4675 debug_printf ("resume_stop request for LWP %ld\n", lwpid_of (thread
));
4680 debug_printf ("stopping LWP %ld\n", lwpid_of (thread
));
4682 /* Stop the thread, and wait for the event asynchronously,
4683 through the event loop. */
4689 debug_printf ("already stopped LWP %ld\n",
4692 /* The LWP may have been stopped in an internal event that
4693 was not meant to be notified back to GDB (e.g., gdbserver
4694 breakpoint), so we should be reporting a stop event in
4697 /* If the thread already has a pending SIGSTOP, this is a
4698 no-op. Otherwise, something later will presumably resume
4699 the thread and this will cause it to cancel any pending
4700 operation, due to last_resume_kind == resume_stop. If
4701 the thread already has a pending status to report, we
4702 will still report it the next time we wait - see
4703 status_pending_p_callback. */
4705 /* If we already have a pending signal to report, then
4706 there's no need to queue a SIGSTOP, as this means we're
4707 midway through moving the LWP out of the jumppad, and we
4708 will report the pending signal as soon as that is
4710 if (lwp
->pending_signals_to_report
== NULL
)
4714 /* For stop requests, we're done. */
4716 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
4720 /* If this thread which is about to be resumed has a pending status,
4721 then don't resume it - we can just report the pending status.
4722 Likewise if it is suspended, because e.g., another thread is
4723 stepping past a breakpoint. Make sure to queue any signals that
4724 would otherwise be sent. In all-stop mode, we do this decision
4725 based on if *any* thread has a pending status. If there's a
4726 thread that needs the step-over-breakpoint dance, then don't
4727 resume any other thread but that particular one. */
4728 leave_pending
= (lwp
->suspended
4729 || lwp
->status_pending_p
4730 || leave_all_stopped
);
4735 debug_printf ("resuming LWP %ld\n", lwpid_of (thread
));
4737 step
= (lwp
->resume
->kind
== resume_step
);
4738 linux_resume_one_lwp (lwp
, step
, lwp
->resume
->sig
, NULL
);
4743 debug_printf ("leaving LWP %ld stopped\n", lwpid_of (thread
));
4745 /* If we have a new signal, enqueue the signal. */
4746 if (lwp
->resume
->sig
!= 0)
4748 struct pending_signals
*p_sig
= XCNEW (struct pending_signals
);
4750 p_sig
->prev
= lwp
->pending_signals
;
4751 p_sig
->signal
= lwp
->resume
->sig
;
4753 /* If this is the same signal we were previously stopped by,
4754 make sure to queue its siginfo. We can ignore the return
4755 value of ptrace; if it fails, we'll skip
4756 PTRACE_SETSIGINFO. */
4757 if (WIFSTOPPED (lwp
->last_status
)
4758 && WSTOPSIG (lwp
->last_status
) == lwp
->resume
->sig
)
4759 ptrace (PTRACE_GETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
4762 lwp
->pending_signals
= p_sig
;
4766 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
4772 linux_resume (struct thread_resume
*resume_info
, size_t n
)
4774 struct thread_resume_array array
= { resume_info
, n
};
4775 struct thread_info
*need_step_over
= NULL
;
4777 int leave_all_stopped
;
4782 debug_printf ("linux_resume:\n");
4785 find_inferior (&all_threads
, linux_set_resume_request
, &array
);
4787 /* If there is a thread which would otherwise be resumed, which has
4788 a pending status, then don't resume any threads - we can just
4789 report the pending status. Make sure to queue any signals that
4790 would otherwise be sent. In non-stop mode, we'll apply this
4791 logic to each thread individually. We consume all pending events
4792 before considering to start a step-over (in all-stop). */
4795 find_inferior (&all_threads
, resume_status_pending_p
, &any_pending
);
4797 /* If there is a thread which would otherwise be resumed, which is
4798 stopped at a breakpoint that needs stepping over, then don't
4799 resume any threads - have it step over the breakpoint with all
4800 other threads stopped, then resume all threads again. Make sure
4801 to queue any signals that would otherwise be delivered or
4803 if (!any_pending
&& supports_breakpoints ())
4805 = (struct thread_info
*) find_inferior (&all_threads
,
4806 need_step_over_p
, NULL
);
4808 leave_all_stopped
= (need_step_over
!= NULL
|| any_pending
);
4812 if (need_step_over
!= NULL
)
4813 debug_printf ("Not resuming all, need step over\n");
4814 else if (any_pending
)
4815 debug_printf ("Not resuming, all-stop and found "
4816 "an LWP with pending status\n");
4818 debug_printf ("Resuming, no pending status or step over needed\n");
4821 /* Even if we're leaving threads stopped, queue all signals we'd
4822 otherwise deliver. */
4823 find_inferior (&all_threads
, linux_resume_one_thread
, &leave_all_stopped
);
4826 start_step_over (get_thread_lwp (need_step_over
));
4830 debug_printf ("linux_resume done\n");
4834 /* We may have events that were pending that can/should be sent to
4835 the client now. Trigger a linux_wait call. */
4836 if (target_is_async_p ())
4840 /* This function is called once per thread. We check the thread's
4841 last resume request, which will tell us whether to resume, step, or
4842 leave the thread stopped. Any signal the client requested to be
4843 delivered has already been enqueued at this point.
4845 If any thread that GDB wants running is stopped at an internal
4846 breakpoint that needs stepping over, we start a step-over operation
4847 on that particular thread, and leave all others stopped. */
4850 proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
4852 struct thread_info
*thread
= (struct thread_info
*) entry
;
4853 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4860 debug_printf ("proceed_one_lwp: lwp %ld\n", lwpid_of (thread
));
4865 debug_printf (" LWP %ld already running\n", lwpid_of (thread
));
4869 if (thread
->last_resume_kind
== resume_stop
4870 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
4873 debug_printf (" client wants LWP to remain %ld stopped\n",
4878 if (lwp
->status_pending_p
)
4881 debug_printf (" LWP %ld has pending status, leaving stopped\n",
4886 gdb_assert (lwp
->suspended
>= 0);
4891 debug_printf (" LWP %ld is suspended\n", lwpid_of (thread
));
4895 if (thread
->last_resume_kind
== resume_stop
4896 && lwp
->pending_signals_to_report
== NULL
4897 && lwp
->collecting_fast_tracepoint
== 0)
4899 /* We haven't reported this LWP as stopped yet (otherwise, the
4900 last_status.kind check above would catch it, and we wouldn't
4901 reach here. This LWP may have been momentarily paused by a
4902 stop_all_lwps call while handling for example, another LWP's
4903 step-over. In that case, the pending expected SIGSTOP signal
4904 that was queued at vCont;t handling time will have already
4905 been consumed by wait_for_sigstop, and so we need to requeue
4906 another one here. Note that if the LWP already has a SIGSTOP
4907 pending, this is a no-op. */
4910 debug_printf ("Client wants LWP %ld to stop. "
4911 "Making sure it has a SIGSTOP pending\n",
4917 if (thread
->last_resume_kind
== resume_step
)
4920 debug_printf (" stepping LWP %ld, client wants it stepping\n",
4924 else if (lwp
->bp_reinsert
!= 0)
4927 debug_printf (" stepping LWP %ld, reinsert set\n",
4934 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
4939 unsuspend_and_proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
4941 struct thread_info
*thread
= (struct thread_info
*) entry
;
4942 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4947 lwp_suspended_decr (lwp
);
4949 return proceed_one_lwp (entry
, except
);
4952 /* When we finish a step-over, set threads running again. If there's
4953 another thread that may need a step-over, now's the time to start
4954 it. Eventually, we'll move all threads past their breakpoints. */
4957 proceed_all_lwps (void)
4959 struct thread_info
*need_step_over
;
4961 /* If there is a thread which would otherwise be resumed, which is
4962 stopped at a breakpoint that needs stepping over, then don't
4963 resume any threads - have it step over the breakpoint with all
4964 other threads stopped, then resume all threads again. */
4966 if (supports_breakpoints ())
4969 = (struct thread_info
*) find_inferior (&all_threads
,
4970 need_step_over_p
, NULL
);
4972 if (need_step_over
!= NULL
)
4975 debug_printf ("proceed_all_lwps: found "
4976 "thread %ld needing a step-over\n",
4977 lwpid_of (need_step_over
));
4979 start_step_over (get_thread_lwp (need_step_over
));
4985 debug_printf ("Proceeding, no step-over needed\n");
4987 find_inferior (&all_threads
, proceed_one_lwp
, NULL
);
4990 /* Stopped LWPs that the client wanted to be running, that don't have
4991 pending statuses, are set to run again, except for EXCEPT, if not
4992 NULL. This undoes a stop_all_lwps call. */
4995 unstop_all_lwps (int unsuspend
, struct lwp_info
*except
)
5001 debug_printf ("unstopping all lwps, except=(LWP %ld)\n",
5002 lwpid_of (get_lwp_thread (except
)));
5004 debug_printf ("unstopping all lwps\n");
5008 find_inferior (&all_threads
, unsuspend_and_proceed_one_lwp
, except
);
5010 find_inferior (&all_threads
, proceed_one_lwp
, except
);
5014 debug_printf ("unstop_all_lwps done\n");
5020 #ifdef HAVE_LINUX_REGSETS
5022 #define use_linux_regsets 1
5024 /* Returns true if REGSET has been disabled. */
5027 regset_disabled (struct regsets_info
*info
, struct regset_info
*regset
)
5029 return (info
->disabled_regsets
!= NULL
5030 && info
->disabled_regsets
[regset
- info
->regsets
]);
5033 /* Disable REGSET. */
5036 disable_regset (struct regsets_info
*info
, struct regset_info
*regset
)
5040 dr_offset
= regset
- info
->regsets
;
5041 if (info
->disabled_regsets
== NULL
)
5042 info
->disabled_regsets
= (char *) xcalloc (1, info
->num_regsets
);
5043 info
->disabled_regsets
[dr_offset
] = 1;
5047 regsets_fetch_inferior_registers (struct regsets_info
*regsets_info
,
5048 struct regcache
*regcache
)
5050 struct regset_info
*regset
;
5051 int saw_general_regs
= 0;
5055 pid
= lwpid_of (current_thread
);
5056 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
5061 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
))
5064 buf
= xmalloc (regset
->size
);
5066 nt_type
= regset
->nt_type
;
5070 iov
.iov_len
= regset
->size
;
5071 data
= (void *) &iov
;
5077 res
= ptrace (regset
->get_request
, pid
,
5078 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5080 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
5086 /* If we get EIO on a regset, do not try it again for
5087 this process mode. */
5088 disable_regset (regsets_info
, regset
);
5090 else if (errno
== ENODATA
)
5092 /* ENODATA may be returned if the regset is currently
5093 not "active". This can happen in normal operation,
5094 so suppress the warning in this case. */
5099 sprintf (s
, "ptrace(regsets_fetch_inferior_registers) PID=%d",
5106 if (regset
->type
== GENERAL_REGS
)
5107 saw_general_regs
= 1;
5108 regset
->store_function (regcache
, buf
);
5112 if (saw_general_regs
)
5119 regsets_store_inferior_registers (struct regsets_info
*regsets_info
,
5120 struct regcache
*regcache
)
5122 struct regset_info
*regset
;
5123 int saw_general_regs
= 0;
5127 pid
= lwpid_of (current_thread
);
5128 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
5133 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
)
5134 || regset
->fill_function
== NULL
)
5137 buf
= xmalloc (regset
->size
);
5139 /* First fill the buffer with the current register set contents,
5140 in case there are any items in the kernel's regset that are
5141 not in gdbserver's regcache. */
5143 nt_type
= regset
->nt_type
;
5147 iov
.iov_len
= regset
->size
;
5148 data
= (void *) &iov
;
5154 res
= ptrace (regset
->get_request
, pid
,
5155 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5157 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
5162 /* Then overlay our cached registers on that. */
5163 regset
->fill_function (regcache
, buf
);
5165 /* Only now do we write the register set. */
5167 res
= ptrace (regset
->set_request
, pid
,
5168 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5170 res
= ptrace (regset
->set_request
, pid
, data
, nt_type
);
5178 /* If we get EIO on a regset, do not try it again for
5179 this process mode. */
5180 disable_regset (regsets_info
, regset
);
5182 else if (errno
== ESRCH
)
5184 /* At this point, ESRCH should mean the process is
5185 already gone, in which case we simply ignore attempts
5186 to change its registers. See also the related
5187 comment in linux_resume_one_lwp. */
5193 perror ("Warning: ptrace(regsets_store_inferior_registers)");
5196 else if (regset
->type
== GENERAL_REGS
)
5197 saw_general_regs
= 1;
5200 if (saw_general_regs
)
5206 #else /* !HAVE_LINUX_REGSETS */
5208 #define use_linux_regsets 0
5209 #define regsets_fetch_inferior_registers(regsets_info, regcache) 1
5210 #define regsets_store_inferior_registers(regsets_info, regcache) 1
5214 /* Return 1 if register REGNO is supported by one of the regset ptrace
5215 calls or 0 if it has to be transferred individually. */
5218 linux_register_in_regsets (const struct regs_info
*regs_info
, int regno
)
5220 unsigned char mask
= 1 << (regno
% 8);
5221 size_t index
= regno
/ 8;
5223 return (use_linux_regsets
5224 && (regs_info
->regset_bitmap
== NULL
5225 || (regs_info
->regset_bitmap
[index
] & mask
) != 0));
5228 #ifdef HAVE_LINUX_USRREGS
5231 register_addr (const struct usrregs_info
*usrregs
, int regnum
)
5235 if (regnum
< 0 || regnum
>= usrregs
->num_regs
)
5236 error ("Invalid register number %d.", regnum
);
5238 addr
= usrregs
->regmap
[regnum
];
5243 /* Fetch one register. */
5245 fetch_register (const struct usrregs_info
*usrregs
,
5246 struct regcache
*regcache
, int regno
)
5253 if (regno
>= usrregs
->num_regs
)
5255 if ((*the_low_target
.cannot_fetch_register
) (regno
))
5258 regaddr
= register_addr (usrregs
, regno
);
5262 size
= ((register_size (regcache
->tdesc
, regno
)
5263 + sizeof (PTRACE_XFER_TYPE
) - 1)
5264 & -sizeof (PTRACE_XFER_TYPE
));
5265 buf
= (char *) alloca (size
);
5267 pid
= lwpid_of (current_thread
);
5268 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
5271 *(PTRACE_XFER_TYPE
*) (buf
+ i
) =
5272 ptrace (PTRACE_PEEKUSER
, pid
,
5273 /* Coerce to a uintptr_t first to avoid potential gcc warning
5274 of coercing an 8 byte integer to a 4 byte pointer. */
5275 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
, (PTRACE_TYPE_ARG4
) 0);
5276 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
5278 error ("reading register %d: %s", regno
, strerror (errno
));
5281 if (the_low_target
.supply_ptrace_register
)
5282 the_low_target
.supply_ptrace_register (regcache
, regno
, buf
);
5284 supply_register (regcache
, regno
, buf
);
5287 /* Store one register. */
5289 store_register (const struct usrregs_info
*usrregs
,
5290 struct regcache
*regcache
, int regno
)
5297 if (regno
>= usrregs
->num_regs
)
5299 if ((*the_low_target
.cannot_store_register
) (regno
))
5302 regaddr
= register_addr (usrregs
, regno
);
5306 size
= ((register_size (regcache
->tdesc
, regno
)
5307 + sizeof (PTRACE_XFER_TYPE
) - 1)
5308 & -sizeof (PTRACE_XFER_TYPE
));
5309 buf
= (char *) alloca (size
);
5310 memset (buf
, 0, size
);
5312 if (the_low_target
.collect_ptrace_register
)
5313 the_low_target
.collect_ptrace_register (regcache
, regno
, buf
);
5315 collect_register (regcache
, regno
, buf
);
5317 pid
= lwpid_of (current_thread
);
5318 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
5321 ptrace (PTRACE_POKEUSER
, pid
,
5322 /* Coerce to a uintptr_t first to avoid potential gcc warning
5323 about coercing an 8 byte integer to a 4 byte pointer. */
5324 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
,
5325 (PTRACE_TYPE_ARG4
) *(PTRACE_XFER_TYPE
*) (buf
+ i
));
5328 /* At this point, ESRCH should mean the process is
5329 already gone, in which case we simply ignore attempts
5330 to change its registers. See also the related
5331 comment in linux_resume_one_lwp. */
5335 if ((*the_low_target
.cannot_store_register
) (regno
) == 0)
5336 error ("writing register %d: %s", regno
, strerror (errno
));
5338 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
5342 /* Fetch all registers, or just one, from the child process.
5343 If REGNO is -1, do this for all registers, skipping any that are
5344 assumed to have been retrieved by regsets_fetch_inferior_registers,
5345 unless ALL is non-zero.
5346 Otherwise, REGNO specifies which register (so we can save time). */
5348 usr_fetch_inferior_registers (const struct regs_info
*regs_info
,
5349 struct regcache
*regcache
, int regno
, int all
)
5351 struct usrregs_info
*usr
= regs_info
->usrregs
;
5355 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
5356 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
5357 fetch_register (usr
, regcache
, regno
);
5360 fetch_register (usr
, regcache
, regno
);
5363 /* Store our register values back into the inferior.
5364 If REGNO is -1, do this for all registers, skipping any that are
5365 assumed to have been saved by regsets_store_inferior_registers,
5366 unless ALL is non-zero.
5367 Otherwise, REGNO specifies which register (so we can save time). */
5369 usr_store_inferior_registers (const struct regs_info
*regs_info
,
5370 struct regcache
*regcache
, int regno
, int all
)
5372 struct usrregs_info
*usr
= regs_info
->usrregs
;
5376 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
5377 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
5378 store_register (usr
, regcache
, regno
);
5381 store_register (usr
, regcache
, regno
);
5384 #else /* !HAVE_LINUX_USRREGS */
5386 #define usr_fetch_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
5387 #define usr_store_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
5393 linux_fetch_registers (struct regcache
*regcache
, int regno
)
5397 const struct regs_info
*regs_info
= (*the_low_target
.regs_info
) ();
5401 if (the_low_target
.fetch_register
!= NULL
5402 && regs_info
->usrregs
!= NULL
)
5403 for (regno
= 0; regno
< regs_info
->usrregs
->num_regs
; regno
++)
5404 (*the_low_target
.fetch_register
) (regcache
, regno
);
5406 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
, regcache
);
5407 if (regs_info
->usrregs
!= NULL
)
5408 usr_fetch_inferior_registers (regs_info
, regcache
, -1, all
);
5412 if (the_low_target
.fetch_register
!= NULL
5413 && (*the_low_target
.fetch_register
) (regcache
, regno
))
5416 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
5418 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
,
5420 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
5421 usr_fetch_inferior_registers (regs_info
, regcache
, regno
, 1);
5426 linux_store_registers (struct regcache
*regcache
, int regno
)
5430 const struct regs_info
*regs_info
= (*the_low_target
.regs_info
) ();
5434 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
5436 if (regs_info
->usrregs
!= NULL
)
5437 usr_store_inferior_registers (regs_info
, regcache
, regno
, all
);
5441 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
5443 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
5445 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
5446 usr_store_inferior_registers (regs_info
, regcache
, regno
, 1);
5451 /* Copy LEN bytes from inferior's memory starting at MEMADDR
5452 to debugger memory starting at MYADDR. */
5455 linux_read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
, int len
)
5457 int pid
= lwpid_of (current_thread
);
5458 register PTRACE_XFER_TYPE
*buffer
;
5459 register CORE_ADDR addr
;
5466 /* Try using /proc. Don't bother for one word. */
5467 if (len
>= 3 * sizeof (long))
5471 /* We could keep this file open and cache it - possibly one per
5472 thread. That requires some juggling, but is even faster. */
5473 sprintf (filename
, "/proc/%d/mem", pid
);
5474 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
5478 /* If pread64 is available, use it. It's faster if the kernel
5479 supports it (only one syscall), and it's 64-bit safe even on
5480 32-bit platforms (for instance, SPARC debugging a SPARC64
5483 bytes
= pread64 (fd
, myaddr
, len
, memaddr
);
5486 if (lseek (fd
, memaddr
, SEEK_SET
) != -1)
5487 bytes
= read (fd
, myaddr
, len
);
5494 /* Some data was read, we'll try to get the rest with ptrace. */
5504 /* Round starting address down to longword boundary. */
5505 addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
5506 /* Round ending address up; get number of longwords that makes. */
5507 count
= ((((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
5508 / sizeof (PTRACE_XFER_TYPE
));
5509 /* Allocate buffer of that many longwords. */
5510 buffer
= XALLOCAVEC (PTRACE_XFER_TYPE
, count
);
5512 /* Read all the longwords */
5514 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
5516 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5517 about coercing an 8 byte integer to a 4 byte pointer. */
5518 buffer
[i
] = ptrace (PTRACE_PEEKTEXT
, pid
,
5519 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5520 (PTRACE_TYPE_ARG4
) 0);
5526 /* Copy appropriate bytes out of the buffer. */
5529 i
*= sizeof (PTRACE_XFER_TYPE
);
5530 i
-= memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1);
5532 (char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
5539 /* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
5540 memory at MEMADDR. On failure (cannot write to the inferior)
5541 returns the value of errno. Always succeeds if LEN is zero. */
5544 linux_write_memory (CORE_ADDR memaddr
, const unsigned char *myaddr
, int len
)
5547 /* Round starting address down to longword boundary. */
5548 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
5549 /* Round ending address up; get number of longwords that makes. */
5551 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
5552 / sizeof (PTRACE_XFER_TYPE
);
5554 /* Allocate buffer of that many longwords. */
5555 register PTRACE_XFER_TYPE
*buffer
= XALLOCAVEC (PTRACE_XFER_TYPE
, count
);
5557 int pid
= lwpid_of (current_thread
);
5561 /* Zero length write always succeeds. */
5567 /* Dump up to four bytes. */
5568 char str
[4 * 2 + 1];
5570 int dump
= len
< 4 ? len
: 4;
5572 for (i
= 0; i
< dump
; i
++)
5574 sprintf (p
, "%02x", myaddr
[i
]);
5579 debug_printf ("Writing %s to 0x%08lx in process %d\n",
5580 str
, (long) memaddr
, pid
);
5583 /* Fill start and end extra bytes of buffer with existing memory data. */
5586 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5587 about coercing an 8 byte integer to a 4 byte pointer. */
5588 buffer
[0] = ptrace (PTRACE_PEEKTEXT
, pid
,
5589 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5590 (PTRACE_TYPE_ARG4
) 0);
5598 = ptrace (PTRACE_PEEKTEXT
, pid
,
5599 /* Coerce to a uintptr_t first to avoid potential gcc warning
5600 about coercing an 8 byte integer to a 4 byte pointer. */
5601 (PTRACE_TYPE_ARG3
) (uintptr_t) (addr
+ (count
- 1)
5602 * sizeof (PTRACE_XFER_TYPE
)),
5603 (PTRACE_TYPE_ARG4
) 0);
5608 /* Copy data to be written over corresponding part of buffer. */
5610 memcpy ((char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
5613 /* Write the entire buffer. */
5615 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
5618 ptrace (PTRACE_POKETEXT
, pid
,
5619 /* Coerce to a uintptr_t first to avoid potential gcc warning
5620 about coercing an 8 byte integer to a 4 byte pointer. */
5621 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5622 (PTRACE_TYPE_ARG4
) buffer
[i
]);
5631 linux_look_up_symbols (void)
5633 #ifdef USE_THREAD_DB
5634 struct process_info
*proc
= current_process ();
5636 if (proc
->priv
->thread_db
!= NULL
)
5644 linux_request_interrupt (void)
5646 extern unsigned long signal_pid
;
5648 /* Send a SIGINT to the process group. This acts just like the user
5649 typed a ^C on the controlling terminal. */
5650 kill (-signal_pid
, SIGINT
);
5653 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
5654 to debugger memory starting at MYADDR. */
5657 linux_read_auxv (CORE_ADDR offset
, unsigned char *myaddr
, unsigned int len
)
5659 char filename
[PATH_MAX
];
5661 int pid
= lwpid_of (current_thread
);
5663 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
5665 fd
= open (filename
, O_RDONLY
);
5669 if (offset
!= (CORE_ADDR
) 0
5670 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
5673 n
= read (fd
, myaddr
, len
);
5680 /* These breakpoint and watchpoint related wrapper functions simply
5681 pass on the function call if the target has registered a
5682 corresponding function. */
5685 linux_supports_z_point_type (char z_type
)
5687 return (the_low_target
.supports_z_point_type
!= NULL
5688 && the_low_target
.supports_z_point_type (z_type
));
5692 linux_insert_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
5693 int size
, struct raw_breakpoint
*bp
)
5695 if (type
== raw_bkpt_type_sw
)
5696 return insert_memory_breakpoint (bp
);
5697 else if (the_low_target
.insert_point
!= NULL
)
5698 return the_low_target
.insert_point (type
, addr
, size
, bp
);
5700 /* Unsupported (see target.h). */
5705 linux_remove_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
5706 int size
, struct raw_breakpoint
*bp
)
5708 if (type
== raw_bkpt_type_sw
)
5709 return remove_memory_breakpoint (bp
);
5710 else if (the_low_target
.remove_point
!= NULL
)
5711 return the_low_target
.remove_point (type
, addr
, size
, bp
);
5713 /* Unsupported (see target.h). */
5717 /* Implement the to_stopped_by_sw_breakpoint target_ops
5721 linux_stopped_by_sw_breakpoint (void)
5723 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5725 return (lwp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
);
5728 /* Implement the to_supports_stopped_by_sw_breakpoint target_ops
5732 linux_supports_stopped_by_sw_breakpoint (void)
5734 return USE_SIGTRAP_SIGINFO
;
5737 /* Implement the to_stopped_by_hw_breakpoint target_ops
5741 linux_stopped_by_hw_breakpoint (void)
5743 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5745 return (lwp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
);
5748 /* Implement the to_supports_stopped_by_hw_breakpoint target_ops
5752 linux_supports_stopped_by_hw_breakpoint (void)
5754 return USE_SIGTRAP_SIGINFO
;
5757 /* Implement the supports_hardware_single_step target_ops method. */
5760 linux_supports_hardware_single_step (void)
5762 return can_hardware_single_step ();
5766 linux_supports_software_single_step (void)
5768 return can_software_single_step ();
5772 linux_stopped_by_watchpoint (void)
5774 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5776 return lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
;
5780 linux_stopped_data_address (void)
5782 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5784 return lwp
->stopped_data_address
;
5787 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
5788 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
5789 && defined(PT_TEXT_END_ADDR)
5791 /* This is only used for targets that define PT_TEXT_ADDR,
5792 PT_DATA_ADDR and PT_TEXT_END_ADDR. If those are not defined, supposedly
5793 the target has different ways of acquiring this information, like
5796 /* Under uClinux, programs are loaded at non-zero offsets, which we need
5797 to tell gdb about. */
5800 linux_read_offsets (CORE_ADDR
*text_p
, CORE_ADDR
*data_p
)
5802 unsigned long text
, text_end
, data
;
5803 int pid
= lwpid_of (current_thread
);
5807 text
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_ADDR
,
5808 (PTRACE_TYPE_ARG4
) 0);
5809 text_end
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_END_ADDR
,
5810 (PTRACE_TYPE_ARG4
) 0);
5811 data
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_DATA_ADDR
,
5812 (PTRACE_TYPE_ARG4
) 0);
5816 /* Both text and data offsets produced at compile-time (and so
5817 used by gdb) are relative to the beginning of the program,
5818 with the data segment immediately following the text segment.
5819 However, the actual runtime layout in memory may put the data
5820 somewhere else, so when we send gdb a data base-address, we
5821 use the real data base address and subtract the compile-time
5822 data base-address from it (which is just the length of the
5823 text segment). BSS immediately follows data in both
5826 *data_p
= data
- (text_end
- text
);
5835 linux_qxfer_osdata (const char *annex
,
5836 unsigned char *readbuf
, unsigned const char *writebuf
,
5837 CORE_ADDR offset
, int len
)
5839 return linux_common_xfer_osdata (annex
, readbuf
, offset
, len
);
5842 /* Convert a native/host siginfo object, into/from the siginfo in the
5843 layout of the inferiors' architecture. */
5846 siginfo_fixup (siginfo_t
*siginfo
, void *inf_siginfo
, int direction
)
5850 if (the_low_target
.siginfo_fixup
!= NULL
)
5851 done
= the_low_target
.siginfo_fixup (siginfo
, inf_siginfo
, direction
);
5853 /* If there was no callback, or the callback didn't do anything,
5854 then just do a straight memcpy. */
5858 memcpy (siginfo
, inf_siginfo
, sizeof (siginfo_t
));
5860 memcpy (inf_siginfo
, siginfo
, sizeof (siginfo_t
));
5865 linux_xfer_siginfo (const char *annex
, unsigned char *readbuf
,
5866 unsigned const char *writebuf
, CORE_ADDR offset
, int len
)
5870 char inf_siginfo
[sizeof (siginfo_t
)];
5872 if (current_thread
== NULL
)
5875 pid
= lwpid_of (current_thread
);
5878 debug_printf ("%s siginfo for lwp %d.\n",
5879 readbuf
!= NULL
? "Reading" : "Writing",
5882 if (offset
>= sizeof (siginfo
))
5885 if (ptrace (PTRACE_GETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
5888 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
5889 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
5890 inferior with a 64-bit GDBSERVER should look the same as debugging it
5891 with a 32-bit GDBSERVER, we need to convert it. */
5892 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
5894 if (offset
+ len
> sizeof (siginfo
))
5895 len
= sizeof (siginfo
) - offset
;
5897 if (readbuf
!= NULL
)
5898 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
5901 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
5903 /* Convert back to ptrace layout before flushing it out. */
5904 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
5906 if (ptrace (PTRACE_SETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
5913 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
5914 so we notice when children change state; as the handler for the
5915 sigsuspend in my_waitpid. */
5918 sigchld_handler (int signo
)
5920 int old_errno
= errno
;
5926 /* fprintf is not async-signal-safe, so call write
5928 if (write (2, "sigchld_handler\n",
5929 sizeof ("sigchld_handler\n") - 1) < 0)
5930 break; /* just ignore */
5934 if (target_is_async_p ())
5935 async_file_mark (); /* trigger a linux_wait */
5941 linux_supports_non_stop (void)
5947 linux_async (int enable
)
5949 int previous
= target_is_async_p ();
5952 debug_printf ("linux_async (%d), previous=%d\n",
5955 if (previous
!= enable
)
5958 sigemptyset (&mask
);
5959 sigaddset (&mask
, SIGCHLD
);
5961 sigprocmask (SIG_BLOCK
, &mask
, NULL
);
5965 if (pipe (linux_event_pipe
) == -1)
5967 linux_event_pipe
[0] = -1;
5968 linux_event_pipe
[1] = -1;
5969 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
5971 warning ("creating event pipe failed.");
5975 fcntl (linux_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
5976 fcntl (linux_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
5978 /* Register the event loop handler. */
5979 add_file_handler (linux_event_pipe
[0],
5980 handle_target_event
, NULL
);
5982 /* Always trigger a linux_wait. */
5987 delete_file_handler (linux_event_pipe
[0]);
5989 close (linux_event_pipe
[0]);
5990 close (linux_event_pipe
[1]);
5991 linux_event_pipe
[0] = -1;
5992 linux_event_pipe
[1] = -1;
5995 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
6002 linux_start_non_stop (int nonstop
)
6004 /* Register or unregister from event-loop accordingly. */
6005 linux_async (nonstop
);
6007 if (target_is_async_p () != (nonstop
!= 0))
6014 linux_supports_multi_process (void)
6019 /* Check if fork events are supported. */
6022 linux_supports_fork_events (void)
6024 return linux_supports_tracefork ();
6027 /* Check if vfork events are supported. */
6030 linux_supports_vfork_events (void)
6032 return linux_supports_tracefork ();
6035 /* Check if exec events are supported. */
6038 linux_supports_exec_events (void)
6040 return linux_supports_traceexec ();
6043 /* Callback for 'find_inferior'. Set the (possibly changed) ptrace
6044 options for the specified lwp. */
6047 reset_lwp_ptrace_options_callback (struct inferior_list_entry
*entry
,
6050 struct thread_info
*thread
= (struct thread_info
*) entry
;
6051 struct lwp_info
*lwp
= get_thread_lwp (thread
);
6055 /* Stop the lwp so we can modify its ptrace options. */
6056 lwp
->must_set_ptrace_flags
= 1;
6057 linux_stop_lwp (lwp
);
6061 /* Already stopped; go ahead and set the ptrace options. */
6062 struct process_info
*proc
= find_process_pid (pid_of (thread
));
6063 int options
= linux_low_ptrace_options (proc
->attached
);
6065 linux_enable_event_reporting (lwpid_of (thread
), options
);
6066 lwp
->must_set_ptrace_flags
= 0;
6072 /* Target hook for 'handle_new_gdb_connection'. Causes a reset of the
6073 ptrace flags for all inferiors. This is in case the new GDB connection
6074 doesn't support the same set of events that the previous one did. */
6077 linux_handle_new_gdb_connection (void)
6081 /* Request that all the lwps reset their ptrace options. */
6082 find_inferior (&all_threads
, reset_lwp_ptrace_options_callback
, &pid
);
6086 linux_supports_disable_randomization (void)
6088 #ifdef HAVE_PERSONALITY
6096 linux_supports_agent (void)
6102 linux_supports_range_stepping (void)
6104 if (*the_low_target
.supports_range_stepping
== NULL
)
6107 return (*the_low_target
.supports_range_stepping
) ();
6110 /* Enumerate spufs IDs for process PID. */
6112 spu_enumerate_spu_ids (long pid
, unsigned char *buf
, CORE_ADDR offset
, int len
)
6118 struct dirent
*entry
;
6120 sprintf (path
, "/proc/%ld/fd", pid
);
6121 dir
= opendir (path
);
6126 while ((entry
= readdir (dir
)) != NULL
)
6132 fd
= atoi (entry
->d_name
);
6136 sprintf (path
, "/proc/%ld/fd/%d", pid
, fd
);
6137 if (stat (path
, &st
) != 0)
6139 if (!S_ISDIR (st
.st_mode
))
6142 if (statfs (path
, &stfs
) != 0)
6144 if (stfs
.f_type
!= SPUFS_MAGIC
)
6147 if (pos
>= offset
&& pos
+ 4 <= offset
+ len
)
6149 *(unsigned int *)(buf
+ pos
- offset
) = fd
;
6159 /* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
6160 object type, using the /proc file system. */
6162 linux_qxfer_spu (const char *annex
, unsigned char *readbuf
,
6163 unsigned const char *writebuf
,
6164 CORE_ADDR offset
, int len
)
6166 long pid
= lwpid_of (current_thread
);
6171 if (!writebuf
&& !readbuf
)
6179 return spu_enumerate_spu_ids (pid
, readbuf
, offset
, len
);
6182 sprintf (buf
, "/proc/%ld/fd/%s", pid
, annex
);
6183 fd
= open (buf
, writebuf
? O_WRONLY
: O_RDONLY
);
6188 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
6195 ret
= write (fd
, writebuf
, (size_t) len
);
6197 ret
= read (fd
, readbuf
, (size_t) len
);
6203 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
6204 struct target_loadseg
6206 /* Core address to which the segment is mapped. */
6208 /* VMA recorded in the program header. */
6210 /* Size of this segment in memory. */
6214 # if defined PT_GETDSBT
6215 struct target_loadmap
6217 /* Protocol version number, must be zero. */
6219 /* Pointer to the DSBT table, its size, and the DSBT index. */
6220 unsigned *dsbt_table
;
6221 unsigned dsbt_size
, dsbt_index
;
6222 /* Number of segments in this map. */
6224 /* The actual memory map. */
6225 struct target_loadseg segs
[/*nsegs*/];
6227 # define LINUX_LOADMAP PT_GETDSBT
6228 # define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
6229 # define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
6231 struct target_loadmap
6233 /* Protocol version number, must be zero. */
6235 /* Number of segments in this map. */
6237 /* The actual memory map. */
6238 struct target_loadseg segs
[/*nsegs*/];
6240 # define LINUX_LOADMAP PTRACE_GETFDPIC
6241 # define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
6242 # define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
6246 linux_read_loadmap (const char *annex
, CORE_ADDR offset
,
6247 unsigned char *myaddr
, unsigned int len
)
6249 int pid
= lwpid_of (current_thread
);
6251 struct target_loadmap
*data
= NULL
;
6252 unsigned int actual_length
, copy_length
;
6254 if (strcmp (annex
, "exec") == 0)
6255 addr
= (int) LINUX_LOADMAP_EXEC
;
6256 else if (strcmp (annex
, "interp") == 0)
6257 addr
= (int) LINUX_LOADMAP_INTERP
;
6261 if (ptrace (LINUX_LOADMAP
, pid
, addr
, &data
) != 0)
6267 actual_length
= sizeof (struct target_loadmap
)
6268 + sizeof (struct target_loadseg
) * data
->nsegs
;
6270 if (offset
< 0 || offset
> actual_length
)
6273 copy_length
= actual_length
- offset
< len
? actual_length
- offset
: len
;
6274 memcpy (myaddr
, (char *) data
+ offset
, copy_length
);
6278 # define linux_read_loadmap NULL
6279 #endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
6282 linux_process_qsupported (char **features
, int count
)
6284 if (the_low_target
.process_qsupported
!= NULL
)
6285 the_low_target
.process_qsupported (features
, count
);
6289 linux_supports_tracepoints (void)
6291 if (*the_low_target
.supports_tracepoints
== NULL
)
6294 return (*the_low_target
.supports_tracepoints
) ();
6298 linux_read_pc (struct regcache
*regcache
)
6300 if (the_low_target
.get_pc
== NULL
)
6303 return (*the_low_target
.get_pc
) (regcache
);
6307 linux_write_pc (struct regcache
*regcache
, CORE_ADDR pc
)
6309 gdb_assert (the_low_target
.set_pc
!= NULL
);
6311 (*the_low_target
.set_pc
) (regcache
, pc
);
6315 linux_thread_stopped (struct thread_info
*thread
)
6317 return get_thread_lwp (thread
)->stopped
;
6320 /* This exposes stop-all-threads functionality to other modules. */
6323 linux_pause_all (int freeze
)
6325 stop_all_lwps (freeze
, NULL
);
6328 /* This exposes unstop-all-threads functionality to other gdbserver
6332 linux_unpause_all (int unfreeze
)
6334 unstop_all_lwps (unfreeze
, NULL
);
6338 linux_prepare_to_access_memory (void)
6340 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6343 linux_pause_all (1);
6348 linux_done_accessing_memory (void)
6350 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6353 linux_unpause_all (1);
6357 linux_install_fast_tracepoint_jump_pad (CORE_ADDR tpoint
, CORE_ADDR tpaddr
,
6358 CORE_ADDR collector
,
6361 CORE_ADDR
*jump_entry
,
6362 CORE_ADDR
*trampoline
,
6363 ULONGEST
*trampoline_size
,
6364 unsigned char *jjump_pad_insn
,
6365 ULONGEST
*jjump_pad_insn_size
,
6366 CORE_ADDR
*adjusted_insn_addr
,
6367 CORE_ADDR
*adjusted_insn_addr_end
,
6370 return (*the_low_target
.install_fast_tracepoint_jump_pad
)
6371 (tpoint
, tpaddr
, collector
, lockaddr
, orig_size
,
6372 jump_entry
, trampoline
, trampoline_size
,
6373 jjump_pad_insn
, jjump_pad_insn_size
,
6374 adjusted_insn_addr
, adjusted_insn_addr_end
,
6378 static struct emit_ops
*
6379 linux_emit_ops (void)
6381 if (the_low_target
.emit_ops
!= NULL
)
6382 return (*the_low_target
.emit_ops
) ();
6388 linux_get_min_fast_tracepoint_insn_len (void)
6390 return (*the_low_target
.get_min_fast_tracepoint_insn_len
) ();
6393 /* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
6396 get_phdr_phnum_from_proc_auxv (const int pid
, const int is_elf64
,
6397 CORE_ADDR
*phdr_memaddr
, int *num_phdr
)
6399 char filename
[PATH_MAX
];
6401 const int auxv_size
= is_elf64
6402 ? sizeof (Elf64_auxv_t
) : sizeof (Elf32_auxv_t
);
6403 char buf
[sizeof (Elf64_auxv_t
)]; /* The larger of the two. */
6405 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
6407 fd
= open (filename
, O_RDONLY
);
6413 while (read (fd
, buf
, auxv_size
) == auxv_size
6414 && (*phdr_memaddr
== 0 || *num_phdr
== 0))
6418 Elf64_auxv_t
*const aux
= (Elf64_auxv_t
*) buf
;
6420 switch (aux
->a_type
)
6423 *phdr_memaddr
= aux
->a_un
.a_val
;
6426 *num_phdr
= aux
->a_un
.a_val
;
6432 Elf32_auxv_t
*const aux
= (Elf32_auxv_t
*) buf
;
6434 switch (aux
->a_type
)
6437 *phdr_memaddr
= aux
->a_un
.a_val
;
6440 *num_phdr
= aux
->a_un
.a_val
;
6448 if (*phdr_memaddr
== 0 || *num_phdr
== 0)
6450 warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
6451 "phdr_memaddr = %ld, phdr_num = %d",
6452 (long) *phdr_memaddr
, *num_phdr
);
6459 /* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
6462 get_dynamic (const int pid
, const int is_elf64
)
6464 CORE_ADDR phdr_memaddr
, relocation
;
6466 unsigned char *phdr_buf
;
6467 const int phdr_size
= is_elf64
? sizeof (Elf64_Phdr
) : sizeof (Elf32_Phdr
);
6469 if (get_phdr_phnum_from_proc_auxv (pid
, is_elf64
, &phdr_memaddr
, &num_phdr
))
6472 gdb_assert (num_phdr
< 100); /* Basic sanity check. */
6473 phdr_buf
= (unsigned char *) alloca (num_phdr
* phdr_size
);
6475 if (linux_read_memory (phdr_memaddr
, phdr_buf
, num_phdr
* phdr_size
))
6478 /* Compute relocation: it is expected to be 0 for "regular" executables,
6479 non-zero for PIE ones. */
6481 for (i
= 0; relocation
== -1 && i
< num_phdr
; i
++)
6484 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6486 if (p
->p_type
== PT_PHDR
)
6487 relocation
= phdr_memaddr
- p
->p_vaddr
;
6491 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6493 if (p
->p_type
== PT_PHDR
)
6494 relocation
= phdr_memaddr
- p
->p_vaddr
;
6497 if (relocation
== -1)
6499 /* PT_PHDR is optional, but necessary for PIE in general. Fortunately
6500 any real world executables, including PIE executables, have always
6501 PT_PHDR present. PT_PHDR is not present in some shared libraries or
6502 in fpc (Free Pascal 2.4) binaries but neither of those have a need for
6503 or present DT_DEBUG anyway (fpc binaries are statically linked).
6505 Therefore if there exists DT_DEBUG there is always also PT_PHDR.
6507 GDB could find RELOCATION also from AT_ENTRY - e_entry. */
6512 for (i
= 0; i
< num_phdr
; i
++)
6516 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6518 if (p
->p_type
== PT_DYNAMIC
)
6519 return p
->p_vaddr
+ relocation
;
6523 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6525 if (p
->p_type
== PT_DYNAMIC
)
6526 return p
->p_vaddr
+ relocation
;
6533 /* Return &_r_debug in the inferior, or -1 if not present. Return value
6534 can be 0 if the inferior does not yet have the library list initialized.
6535 We look for DT_MIPS_RLD_MAP first. MIPS executables use this instead of
6536 DT_DEBUG, although they sometimes contain an unused DT_DEBUG entry too. */
6539 get_r_debug (const int pid
, const int is_elf64
)
6541 CORE_ADDR dynamic_memaddr
;
6542 const int dyn_size
= is_elf64
? sizeof (Elf64_Dyn
) : sizeof (Elf32_Dyn
);
6543 unsigned char buf
[sizeof (Elf64_Dyn
)]; /* The larger of the two. */
6546 dynamic_memaddr
= get_dynamic (pid
, is_elf64
);
6547 if (dynamic_memaddr
== 0)
6550 while (linux_read_memory (dynamic_memaddr
, buf
, dyn_size
) == 0)
6554 Elf64_Dyn
*const dyn
= (Elf64_Dyn
*) buf
;
6555 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
6559 unsigned char buf
[sizeof (Elf64_Xword
)];
6563 #ifdef DT_MIPS_RLD_MAP
6564 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
6566 if (linux_read_memory (dyn
->d_un
.d_val
,
6567 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6572 #endif /* DT_MIPS_RLD_MAP */
6573 #ifdef DT_MIPS_RLD_MAP_REL
6574 if (dyn
->d_tag
== DT_MIPS_RLD_MAP_REL
)
6576 if (linux_read_memory (dyn
->d_un
.d_val
+ dynamic_memaddr
,
6577 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6582 #endif /* DT_MIPS_RLD_MAP_REL */
6584 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
6585 map
= dyn
->d_un
.d_val
;
6587 if (dyn
->d_tag
== DT_NULL
)
6592 Elf32_Dyn
*const dyn
= (Elf32_Dyn
*) buf
;
6593 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
6597 unsigned char buf
[sizeof (Elf32_Word
)];
6601 #ifdef DT_MIPS_RLD_MAP
6602 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
6604 if (linux_read_memory (dyn
->d_un
.d_val
,
6605 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6610 #endif /* DT_MIPS_RLD_MAP */
6611 #ifdef DT_MIPS_RLD_MAP_REL
6612 if (dyn
->d_tag
== DT_MIPS_RLD_MAP_REL
)
6614 if (linux_read_memory (dyn
->d_un
.d_val
+ dynamic_memaddr
,
6615 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6620 #endif /* DT_MIPS_RLD_MAP_REL */
6622 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
6623 map
= dyn
->d_un
.d_val
;
6625 if (dyn
->d_tag
== DT_NULL
)
6629 dynamic_memaddr
+= dyn_size
;
6635 /* Read one pointer from MEMADDR in the inferior. */
6638 read_one_ptr (CORE_ADDR memaddr
, CORE_ADDR
*ptr
, int ptr_size
)
6642 /* Go through a union so this works on either big or little endian
6643 hosts, when the inferior's pointer size is smaller than the size
6644 of CORE_ADDR. It is assumed the inferior's endianness is the
6645 same of the superior's. */
6648 CORE_ADDR core_addr
;
6653 ret
= linux_read_memory (memaddr
, &addr
.uc
, ptr_size
);
6656 if (ptr_size
== sizeof (CORE_ADDR
))
6657 *ptr
= addr
.core_addr
;
6658 else if (ptr_size
== sizeof (unsigned int))
6661 gdb_assert_not_reached ("unhandled pointer size");
6666 struct link_map_offsets
6668 /* Offset and size of r_debug.r_version. */
6669 int r_version_offset
;
6671 /* Offset and size of r_debug.r_map. */
6674 /* Offset to l_addr field in struct link_map. */
6677 /* Offset to l_name field in struct link_map. */
6680 /* Offset to l_ld field in struct link_map. */
6683 /* Offset to l_next field in struct link_map. */
6686 /* Offset to l_prev field in struct link_map. */
6690 /* Construct qXfer:libraries-svr4:read reply. */
6693 linux_qxfer_libraries_svr4 (const char *annex
, unsigned char *readbuf
,
6694 unsigned const char *writebuf
,
6695 CORE_ADDR offset
, int len
)
6698 unsigned document_len
;
6699 struct process_info_private
*const priv
= current_process ()->priv
;
6700 char filename
[PATH_MAX
];
6703 static const struct link_map_offsets lmo_32bit_offsets
=
6705 0, /* r_version offset. */
6706 4, /* r_debug.r_map offset. */
6707 0, /* l_addr offset in link_map. */
6708 4, /* l_name offset in link_map. */
6709 8, /* l_ld offset in link_map. */
6710 12, /* l_next offset in link_map. */
6711 16 /* l_prev offset in link_map. */
6714 static const struct link_map_offsets lmo_64bit_offsets
=
6716 0, /* r_version offset. */
6717 8, /* r_debug.r_map offset. */
6718 0, /* l_addr offset in link_map. */
6719 8, /* l_name offset in link_map. */
6720 16, /* l_ld offset in link_map. */
6721 24, /* l_next offset in link_map. */
6722 32 /* l_prev offset in link_map. */
6724 const struct link_map_offsets
*lmo
;
6725 unsigned int machine
;
6727 CORE_ADDR lm_addr
= 0, lm_prev
= 0;
6728 int allocated
= 1024;
6730 CORE_ADDR l_name
, l_addr
, l_ld
, l_next
, l_prev
;
6731 int header_done
= 0;
6733 if (writebuf
!= NULL
)
6735 if (readbuf
== NULL
)
6738 pid
= lwpid_of (current_thread
);
6739 xsnprintf (filename
, sizeof filename
, "/proc/%d/exe", pid
);
6740 is_elf64
= elf_64_file_p (filename
, &machine
);
6741 lmo
= is_elf64
? &lmo_64bit_offsets
: &lmo_32bit_offsets
;
6742 ptr_size
= is_elf64
? 8 : 4;
6744 while (annex
[0] != '\0')
6750 sep
= strchr (annex
, '=');
6755 if (len
== 5 && startswith (annex
, "start"))
6757 else if (len
== 4 && startswith (annex
, "prev"))
6761 annex
= strchr (sep
, ';');
6768 annex
= decode_address_to_semicolon (addrp
, sep
+ 1);
6775 if (priv
->r_debug
== 0)
6776 priv
->r_debug
= get_r_debug (pid
, is_elf64
);
6778 /* We failed to find DT_DEBUG. Such situation will not change
6779 for this inferior - do not retry it. Report it to GDB as
6780 E01, see for the reasons at the GDB solib-svr4.c side. */
6781 if (priv
->r_debug
== (CORE_ADDR
) -1)
6784 if (priv
->r_debug
!= 0)
6786 if (linux_read_memory (priv
->r_debug
+ lmo
->r_version_offset
,
6787 (unsigned char *) &r_version
,
6788 sizeof (r_version
)) != 0
6791 warning ("unexpected r_debug version %d", r_version
);
6793 else if (read_one_ptr (priv
->r_debug
+ lmo
->r_map_offset
,
6794 &lm_addr
, ptr_size
) != 0)
6796 warning ("unable to read r_map from 0x%lx",
6797 (long) priv
->r_debug
+ lmo
->r_map_offset
);
6802 document
= (char *) xmalloc (allocated
);
6803 strcpy (document
, "<library-list-svr4 version=\"1.0\"");
6804 p
= document
+ strlen (document
);
6807 && read_one_ptr (lm_addr
+ lmo
->l_name_offset
,
6808 &l_name
, ptr_size
) == 0
6809 && read_one_ptr (lm_addr
+ lmo
->l_addr_offset
,
6810 &l_addr
, ptr_size
) == 0
6811 && read_one_ptr (lm_addr
+ lmo
->l_ld_offset
,
6812 &l_ld
, ptr_size
) == 0
6813 && read_one_ptr (lm_addr
+ lmo
->l_prev_offset
,
6814 &l_prev
, ptr_size
) == 0
6815 && read_one_ptr (lm_addr
+ lmo
->l_next_offset
,
6816 &l_next
, ptr_size
) == 0)
6818 unsigned char libname
[PATH_MAX
];
6820 if (lm_prev
!= l_prev
)
6822 warning ("Corrupted shared library list: 0x%lx != 0x%lx",
6823 (long) lm_prev
, (long) l_prev
);
6827 /* Ignore the first entry even if it has valid name as the first entry
6828 corresponds to the main executable. The first entry should not be
6829 skipped if the dynamic loader was loaded late by a static executable
6830 (see solib-svr4.c parameter ignore_first). But in such case the main
6831 executable does not have PT_DYNAMIC present and this function already
6832 exited above due to failed get_r_debug. */
6835 sprintf (p
, " main-lm=\"0x%lx\"", (unsigned long) lm_addr
);
6840 /* Not checking for error because reading may stop before
6841 we've got PATH_MAX worth of characters. */
6843 linux_read_memory (l_name
, libname
, sizeof (libname
) - 1);
6844 libname
[sizeof (libname
) - 1] = '\0';
6845 if (libname
[0] != '\0')
6847 /* 6x the size for xml_escape_text below. */
6848 size_t len
= 6 * strlen ((char *) libname
);
6853 /* Terminate `<library-list-svr4'. */
6858 while (allocated
< p
- document
+ len
+ 200)
6860 /* Expand to guarantee sufficient storage. */
6861 uintptr_t document_len
= p
- document
;
6863 document
= (char *) xrealloc (document
, 2 * allocated
);
6865 p
= document
+ document_len
;
6868 name
= xml_escape_text ((char *) libname
);
6869 p
+= sprintf (p
, "<library name=\"%s\" lm=\"0x%lx\" "
6870 "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
6871 name
, (unsigned long) lm_addr
,
6872 (unsigned long) l_addr
, (unsigned long) l_ld
);
6883 /* Empty list; terminate `<library-list-svr4'. */
6887 strcpy (p
, "</library-list-svr4>");
6889 document_len
= strlen (document
);
6890 if (offset
< document_len
)
6891 document_len
-= offset
;
6894 if (len
> document_len
)
6897 memcpy (readbuf
, document
+ offset
, len
);
6903 #ifdef HAVE_LINUX_BTRACE
6905 /* See to_disable_btrace target method. */
6908 linux_low_disable_btrace (struct btrace_target_info
*tinfo
)
6910 enum btrace_error err
;
6912 err
= linux_disable_btrace (tinfo
);
6913 return (err
== BTRACE_ERR_NONE
? 0 : -1);
6916 /* Encode an Intel(R) Processor Trace configuration. */
6919 linux_low_encode_pt_config (struct buffer
*buffer
,
6920 const struct btrace_data_pt_config
*config
)
6922 buffer_grow_str (buffer
, "<pt-config>\n");
6924 switch (config
->cpu
.vendor
)
6927 buffer_xml_printf (buffer
, "<cpu vendor=\"GenuineIntel\" family=\"%u\" "
6928 "model=\"%u\" stepping=\"%u\"/>\n",
6929 config
->cpu
.family
, config
->cpu
.model
,
6930 config
->cpu
.stepping
);
6937 buffer_grow_str (buffer
, "</pt-config>\n");
6940 /* Encode a raw buffer. */
6943 linux_low_encode_raw (struct buffer
*buffer
, const gdb_byte
*data
,
6949 /* We use hex encoding - see common/rsp-low.h. */
6950 buffer_grow_str (buffer
, "<raw>\n");
6956 elem
[0] = tohex ((*data
>> 4) & 0xf);
6957 elem
[1] = tohex (*data
++ & 0xf);
6959 buffer_grow (buffer
, elem
, 2);
6962 buffer_grow_str (buffer
, "</raw>\n");
6965 /* See to_read_btrace target method. */
6968 linux_low_read_btrace (struct btrace_target_info
*tinfo
, struct buffer
*buffer
,
6969 enum btrace_read_type type
)
6971 struct btrace_data btrace
;
6972 struct btrace_block
*block
;
6973 enum btrace_error err
;
6976 btrace_data_init (&btrace
);
6978 err
= linux_read_btrace (&btrace
, tinfo
, type
);
6979 if (err
!= BTRACE_ERR_NONE
)
6981 if (err
== BTRACE_ERR_OVERFLOW
)
6982 buffer_grow_str0 (buffer
, "E.Overflow.");
6984 buffer_grow_str0 (buffer
, "E.Generic Error.");
6989 switch (btrace
.format
)
6991 case BTRACE_FORMAT_NONE
:
6992 buffer_grow_str0 (buffer
, "E.No Trace.");
6995 case BTRACE_FORMAT_BTS
:
6996 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
6997 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
7000 VEC_iterate (btrace_block_s
, btrace
.variant
.bts
.blocks
, i
, block
);
7002 buffer_xml_printf (buffer
, "<block begin=\"0x%s\" end=\"0x%s\"/>\n",
7003 paddress (block
->begin
), paddress (block
->end
));
7005 buffer_grow_str0 (buffer
, "</btrace>\n");
7008 case BTRACE_FORMAT_PT
:
7009 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
7010 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
7011 buffer_grow_str (buffer
, "<pt>\n");
7013 linux_low_encode_pt_config (buffer
, &btrace
.variant
.pt
.config
);
7015 linux_low_encode_raw (buffer
, btrace
.variant
.pt
.data
,
7016 btrace
.variant
.pt
.size
);
7018 buffer_grow_str (buffer
, "</pt>\n");
7019 buffer_grow_str0 (buffer
, "</btrace>\n");
7023 buffer_grow_str0 (buffer
, "E.Unsupported Trace Format.");
7027 btrace_data_fini (&btrace
);
7031 btrace_data_fini (&btrace
);
7035 /* See to_btrace_conf target method. */
7038 linux_low_btrace_conf (const struct btrace_target_info
*tinfo
,
7039 struct buffer
*buffer
)
7041 const struct btrace_config
*conf
;
7043 buffer_grow_str (buffer
, "<!DOCTYPE btrace-conf SYSTEM \"btrace-conf.dtd\">\n");
7044 buffer_grow_str (buffer
, "<btrace-conf version=\"1.0\">\n");
7046 conf
= linux_btrace_conf (tinfo
);
7049 switch (conf
->format
)
7051 case BTRACE_FORMAT_NONE
:
7054 case BTRACE_FORMAT_BTS
:
7055 buffer_xml_printf (buffer
, "<bts");
7056 buffer_xml_printf (buffer
, " size=\"0x%x\"", conf
->bts
.size
);
7057 buffer_xml_printf (buffer
, " />\n");
7060 case BTRACE_FORMAT_PT
:
7061 buffer_xml_printf (buffer
, "<pt");
7062 buffer_xml_printf (buffer
, " size=\"0x%x\"", conf
->pt
.size
);
7063 buffer_xml_printf (buffer
, "/>\n");
7068 buffer_grow_str0 (buffer
, "</btrace-conf>\n");
7071 #endif /* HAVE_LINUX_BTRACE */
7073 /* See nat/linux-nat.h. */
7076 current_lwp_ptid (void)
7078 return ptid_of (current_thread
);
7081 /* Implementation of the target_ops method "breakpoint_kind_from_pc". */
7084 linux_breakpoint_kind_from_pc (CORE_ADDR
*pcptr
)
7086 if (the_low_target
.breakpoint_kind_from_pc
!= NULL
)
7087 return (*the_low_target
.breakpoint_kind_from_pc
) (pcptr
);
7089 return default_breakpoint_kind_from_pc (pcptr
);
7092 /* Implementation of the target_ops method "sw_breakpoint_from_kind". */
7094 static const gdb_byte
*
7095 linux_sw_breakpoint_from_kind (int kind
, int *size
)
7097 gdb_assert (the_low_target
.sw_breakpoint_from_kind
!= NULL
);
7099 return (*the_low_target
.sw_breakpoint_from_kind
) (kind
, size
);
7102 /* Implementation of the target_ops method
7103 "breakpoint_kind_from_current_state". */
7106 linux_breakpoint_kind_from_current_state (CORE_ADDR
*pcptr
)
7108 if (the_low_target
.breakpoint_kind_from_current_state
!= NULL
)
7109 return (*the_low_target
.breakpoint_kind_from_current_state
) (pcptr
);
7111 return linux_breakpoint_kind_from_pc (pcptr
);
7114 static struct target_ops linux_target_ops
= {
7115 linux_create_inferior
,
7116 linux_post_create_inferior
,
7125 linux_fetch_registers
,
7126 linux_store_registers
,
7127 linux_prepare_to_access_memory
,
7128 linux_done_accessing_memory
,
7131 linux_look_up_symbols
,
7132 linux_request_interrupt
,
7134 linux_supports_z_point_type
,
7137 linux_stopped_by_sw_breakpoint
,
7138 linux_supports_stopped_by_sw_breakpoint
,
7139 linux_stopped_by_hw_breakpoint
,
7140 linux_supports_stopped_by_hw_breakpoint
,
7141 linux_supports_hardware_single_step
,
7142 linux_stopped_by_watchpoint
,
7143 linux_stopped_data_address
,
7144 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
7145 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
7146 && defined(PT_TEXT_END_ADDR)
7151 #ifdef USE_THREAD_DB
7152 thread_db_get_tls_address
,
7157 hostio_last_error_from_errno
,
7160 linux_supports_non_stop
,
7162 linux_start_non_stop
,
7163 linux_supports_multi_process
,
7164 linux_supports_fork_events
,
7165 linux_supports_vfork_events
,
7166 linux_supports_exec_events
,
7167 linux_handle_new_gdb_connection
,
7168 #ifdef USE_THREAD_DB
7169 thread_db_handle_monitor_command
,
7173 linux_common_core_of_thread
,
7175 linux_process_qsupported
,
7176 linux_supports_tracepoints
,
7179 linux_thread_stopped
,
7183 linux_stabilize_threads
,
7184 linux_install_fast_tracepoint_jump_pad
,
7186 linux_supports_disable_randomization
,
7187 linux_get_min_fast_tracepoint_insn_len
,
7188 linux_qxfer_libraries_svr4
,
7189 linux_supports_agent
,
7190 #ifdef HAVE_LINUX_BTRACE
7191 linux_supports_btrace
,
7192 linux_enable_btrace
,
7193 linux_low_disable_btrace
,
7194 linux_low_read_btrace
,
7195 linux_low_btrace_conf
,
7203 linux_supports_range_stepping
,
7204 linux_proc_pid_to_exec_file
,
7205 linux_mntns_open_cloexec
,
7207 linux_mntns_readlink
,
7208 linux_breakpoint_kind_from_pc
,
7209 linux_sw_breakpoint_from_kind
,
7210 linux_proc_tid_get_name
,
7211 linux_breakpoint_kind_from_current_state
,
7212 linux_supports_software_single_step
7215 #ifdef HAVE_LINUX_REGSETS
7217 initialize_regsets_info (struct regsets_info
*info
)
7219 for (info
->num_regsets
= 0;
7220 info
->regsets
[info
->num_regsets
].size
>= 0;
7221 info
->num_regsets
++)
7227 initialize_low (void)
7229 struct sigaction sigchld_action
;
7231 memset (&sigchld_action
, 0, sizeof (sigchld_action
));
7232 set_target_ops (&linux_target_ops
);
7234 linux_ptrace_init_warnings ();
7236 sigchld_action
.sa_handler
= sigchld_handler
;
7237 sigemptyset (&sigchld_action
.sa_mask
);
7238 sigchld_action
.sa_flags
= SA_RESTART
;
7239 sigaction (SIGCHLD
, &sigchld_action
, NULL
);
7241 initialize_low_arch ();
7243 linux_check_ptrace_features ();