1 /* Low level interface to ptrace, for the remote server for GDB.
2 Copyright (C) 1995-2015 Free Software Foundation, Inc.
4 This file is part of GDB.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>. */
20 #include "linux-low.h"
21 #include "nat/linux-osdata.h"
26 #include "nat/linux-nat.h"
27 #include "nat/linux-waitpid.h"
29 #include "nat/gdb_ptrace.h"
30 #include "nat/linux-ptrace.h"
31 #include "nat/linux-procfs.h"
32 #include "nat/linux-personality.h"
34 #include <sys/ioctl.h>
37 #include <sys/syscall.h>
41 #include <sys/types.h>
46 #include "filestuff.h"
47 #include "tracepoint.h"
50 /* Don't include <linux/elf.h> here. If it got included by gdb_proc_service.h
51 then ELFMAG0 will have been defined. If it didn't get included by
52 gdb_proc_service.h then including it will likely introduce a duplicate
53 definition of elf_fpregset_t. */
56 #include "nat/linux-namespaces.h"
59 #define SPUFS_MAGIC 0x23c9b64e
62 #ifdef HAVE_PERSONALITY
63 # include <sys/personality.h>
64 # if !HAVE_DECL_ADDR_NO_RANDOMIZE
65 # define ADDR_NO_RANDOMIZE 0x0040000
73 /* Some targets did not define these ptrace constants from the start,
74 so gdbserver defines them locally here. In the future, these may
75 be removed after they are added to asm/ptrace.h. */
76 #if !(defined(PT_TEXT_ADDR) \
77 || defined(PT_DATA_ADDR) \
78 || defined(PT_TEXT_END_ADDR))
79 #if defined(__mcoldfire__)
80 /* These are still undefined in 3.10 kernels. */
81 #define PT_TEXT_ADDR 49*4
82 #define PT_DATA_ADDR 50*4
83 #define PT_TEXT_END_ADDR 51*4
84 /* BFIN already defines these since at least 2.6.32 kernels. */
86 #define PT_TEXT_ADDR 220
87 #define PT_TEXT_END_ADDR 224
88 #define PT_DATA_ADDR 228
89 /* These are still undefined in 3.10 kernels. */
90 #elif defined(__TMS320C6X__)
91 #define PT_TEXT_ADDR (0x10000*4)
92 #define PT_DATA_ADDR (0x10004*4)
93 #define PT_TEXT_END_ADDR (0x10008*4)
97 #ifdef HAVE_LINUX_BTRACE
98 # include "nat/linux-btrace.h"
99 # include "btrace-common.h"
102 #ifndef HAVE_ELF32_AUXV_T
103 /* Copied from glibc's elf.h. */
106 uint32_t a_type
; /* Entry type */
109 uint32_t a_val
; /* Integer value */
110 /* We use to have pointer elements added here. We cannot do that,
111 though, since it does not work when using 32-bit definitions
112 on 64-bit platforms and vice versa. */
117 #ifndef HAVE_ELF64_AUXV_T
118 /* Copied from glibc's elf.h. */
121 uint64_t a_type
; /* Entry type */
124 uint64_t a_val
; /* Integer value */
125 /* We use to have pointer elements added here. We cannot do that,
126 though, since it does not work when using 32-bit definitions
127 on 64-bit platforms and vice versa. */
132 /* Does the current host support PTRACE_GETREGSET? */
133 int have_ptrace_getregset
= -1;
137 /* See nat/linux-nat.h. */
140 ptid_of_lwp (struct lwp_info
*lwp
)
142 return ptid_of (get_lwp_thread (lwp
));
145 /* See nat/linux-nat.h. */
148 lwp_set_arch_private_info (struct lwp_info
*lwp
,
149 struct arch_lwp_info
*info
)
151 lwp
->arch_private
= info
;
154 /* See nat/linux-nat.h. */
156 struct arch_lwp_info
*
157 lwp_arch_private_info (struct lwp_info
*lwp
)
159 return lwp
->arch_private
;
162 /* See nat/linux-nat.h. */
165 lwp_is_stopped (struct lwp_info
*lwp
)
170 /* See nat/linux-nat.h. */
172 enum target_stop_reason
173 lwp_stop_reason (struct lwp_info
*lwp
)
175 return lwp
->stop_reason
;
178 /* A list of all unknown processes which receive stop signals. Some
179 other process will presumably claim each of these as forked
180 children momentarily. */
182 struct simple_pid_list
184 /* The process ID. */
187 /* The status as reported by waitpid. */
191 struct simple_pid_list
*next
;
193 struct simple_pid_list
*stopped_pids
;
195 /* Trivial list manipulation functions to keep track of a list of new
196 stopped processes. */
199 add_to_pid_list (struct simple_pid_list
**listp
, int pid
, int status
)
201 struct simple_pid_list
*new_pid
= XNEW (struct simple_pid_list
);
204 new_pid
->status
= status
;
205 new_pid
->next
= *listp
;
210 pull_pid_from_list (struct simple_pid_list
**listp
, int pid
, int *statusp
)
212 struct simple_pid_list
**p
;
214 for (p
= listp
; *p
!= NULL
; p
= &(*p
)->next
)
215 if ((*p
)->pid
== pid
)
217 struct simple_pid_list
*next
= (*p
)->next
;
219 *statusp
= (*p
)->status
;
227 enum stopping_threads_kind
229 /* Not stopping threads presently. */
230 NOT_STOPPING_THREADS
,
232 /* Stopping threads. */
235 /* Stopping and suspending threads. */
236 STOPPING_AND_SUSPENDING_THREADS
239 /* This is set while stop_all_lwps is in effect. */
240 enum stopping_threads_kind stopping_threads
= NOT_STOPPING_THREADS
;
242 /* FIXME make into a target method? */
243 int using_threads
= 1;
245 /* True if we're presently stabilizing threads (moving them out of
247 static int stabilizing_threads
;
249 static void linux_resume_one_lwp (struct lwp_info
*lwp
,
250 int step
, int signal
, siginfo_t
*info
);
251 static void linux_resume (struct thread_resume
*resume_info
, size_t n
);
252 static void stop_all_lwps (int suspend
, struct lwp_info
*except
);
253 static void unstop_all_lwps (int unsuspend
, struct lwp_info
*except
);
254 static int linux_wait_for_event_filtered (ptid_t wait_ptid
, ptid_t filter_ptid
,
255 int *wstat
, int options
);
256 static int linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
);
257 static struct lwp_info
*add_lwp (ptid_t ptid
);
258 static void linux_mourn (struct process_info
*process
);
259 static int linux_stopped_by_watchpoint (void);
260 static void mark_lwp_dead (struct lwp_info
*lwp
, int wstat
);
261 static int lwp_is_marked_dead (struct lwp_info
*lwp
);
262 static void proceed_all_lwps (void);
263 static int finish_step_over (struct lwp_info
*lwp
);
264 static int kill_lwp (unsigned long lwpid
, int signo
);
265 static void enqueue_pending_signal (struct lwp_info
*lwp
, int signal
, siginfo_t
*info
);
266 static void complete_ongoing_step_over (void);
268 /* When the event-loop is doing a step-over, this points at the thread
270 ptid_t step_over_bkpt
;
272 /* True if the low target can hardware single-step. Such targets
273 don't need a BREAKPOINT_REINSERT_ADDR callback. */
276 can_hardware_single_step (void)
278 return (the_low_target
.breakpoint_reinsert_addr
== NULL
);
281 /* True if the low target supports memory breakpoints. If so, we'll
282 have a GET_PC implementation. */
285 supports_breakpoints (void)
287 return (the_low_target
.get_pc
!= NULL
);
290 /* Returns true if this target can support fast tracepoints. This
291 does not mean that the in-process agent has been loaded in the
295 supports_fast_tracepoints (void)
297 return the_low_target
.install_fast_tracepoint_jump_pad
!= NULL
;
300 /* True if LWP is stopped in its stepping range. */
303 lwp_in_step_range (struct lwp_info
*lwp
)
305 CORE_ADDR pc
= lwp
->stop_pc
;
307 return (pc
>= lwp
->step_range_start
&& pc
< lwp
->step_range_end
);
310 struct pending_signals
314 struct pending_signals
*prev
;
317 /* The read/write ends of the pipe registered as waitable file in the
319 static int linux_event_pipe
[2] = { -1, -1 };
321 /* True if we're currently in async mode. */
322 #define target_is_async_p() (linux_event_pipe[0] != -1)
324 static void send_sigstop (struct lwp_info
*lwp
);
325 static void wait_for_sigstop (void);
327 /* Return non-zero if HEADER is a 64-bit ELF file. */
330 elf_64_header_p (const Elf64_Ehdr
*header
, unsigned int *machine
)
332 if (header
->e_ident
[EI_MAG0
] == ELFMAG0
333 && header
->e_ident
[EI_MAG1
] == ELFMAG1
334 && header
->e_ident
[EI_MAG2
] == ELFMAG2
335 && header
->e_ident
[EI_MAG3
] == ELFMAG3
)
337 *machine
= header
->e_machine
;
338 return header
->e_ident
[EI_CLASS
] == ELFCLASS64
;
345 /* Return non-zero if FILE is a 64-bit ELF file,
346 zero if the file is not a 64-bit ELF file,
347 and -1 if the file is not accessible or doesn't exist. */
350 elf_64_file_p (const char *file
, unsigned int *machine
)
355 fd
= open (file
, O_RDONLY
);
359 if (read (fd
, &header
, sizeof (header
)) != sizeof (header
))
366 return elf_64_header_p (&header
, machine
);
369 /* Accepts an integer PID; Returns true if the executable PID is
370 running is a 64-bit ELF file.. */
373 linux_pid_exe_is_elf_64_file (int pid
, unsigned int *machine
)
377 sprintf (file
, "/proc/%d/exe", pid
);
378 return elf_64_file_p (file
, machine
);
382 delete_lwp (struct lwp_info
*lwp
)
384 struct thread_info
*thr
= get_lwp_thread (lwp
);
387 debug_printf ("deleting %ld\n", lwpid_of (thr
));
390 free (lwp
->arch_private
);
394 /* Add a process to the common process list, and set its private
397 static struct process_info
*
398 linux_add_process (int pid
, int attached
)
400 struct process_info
*proc
;
402 proc
= add_process (pid
, attached
);
403 proc
->priv
= XCNEW (struct process_info_private
);
405 if (the_low_target
.new_process
!= NULL
)
406 proc
->priv
->arch_private
= the_low_target
.new_process ();
411 static CORE_ADDR
get_pc (struct lwp_info
*lwp
);
413 /* Implement the arch_setup target_ops method. */
416 linux_arch_setup (void)
418 the_low_target
.arch_setup ();
421 /* Call the target arch_setup function on THREAD. */
424 linux_arch_setup_thread (struct thread_info
*thread
)
426 struct thread_info
*saved_thread
;
428 saved_thread
= current_thread
;
429 current_thread
= thread
;
433 current_thread
= saved_thread
;
436 /* Handle a GNU/Linux extended wait response. If we see a clone,
437 fork, or vfork event, we need to add the new LWP to our list
438 (and return 0 so as not to report the trap to higher layers).
439 If we see an exec event, we will modify ORIG_EVENT_LWP to point
440 to a new LWP representing the new program. */
443 handle_extended_wait (struct lwp_info
**orig_event_lwp
, int wstat
)
445 struct lwp_info
*event_lwp
= *orig_event_lwp
;
446 int event
= linux_ptrace_get_extended_event (wstat
);
447 struct thread_info
*event_thr
= get_lwp_thread (event_lwp
);
448 struct lwp_info
*new_lwp
;
450 gdb_assert (event_lwp
->waitstatus
.kind
== TARGET_WAITKIND_IGNORE
);
452 if ((event
== PTRACE_EVENT_FORK
) || (event
== PTRACE_EVENT_VFORK
)
453 || (event
== PTRACE_EVENT_CLONE
))
456 unsigned long new_pid
;
459 /* Get the pid of the new lwp. */
460 ptrace (PTRACE_GETEVENTMSG
, lwpid_of (event_thr
), (PTRACE_TYPE_ARG3
) 0,
463 /* If we haven't already seen the new PID stop, wait for it now. */
464 if (!pull_pid_from_list (&stopped_pids
, new_pid
, &status
))
466 /* The new child has a pending SIGSTOP. We can't affect it until it
467 hits the SIGSTOP, but we're already attached. */
469 ret
= my_waitpid (new_pid
, &status
, __WALL
);
472 perror_with_name ("waiting for new child");
473 else if (ret
!= new_pid
)
474 warning ("wait returned unexpected PID %d", ret
);
475 else if (!WIFSTOPPED (status
))
476 warning ("wait returned unexpected status 0x%x", status
);
479 if (event
== PTRACE_EVENT_FORK
|| event
== PTRACE_EVENT_VFORK
)
481 struct process_info
*parent_proc
;
482 struct process_info
*child_proc
;
483 struct lwp_info
*child_lwp
;
484 struct thread_info
*child_thr
;
485 struct target_desc
*tdesc
;
487 ptid
= ptid_build (new_pid
, new_pid
, 0);
491 debug_printf ("HEW: Got fork event from LWP %ld, "
493 ptid_get_lwp (ptid_of (event_thr
)),
494 ptid_get_pid (ptid
));
497 /* Add the new process to the tables and clone the breakpoint
498 lists of the parent. We need to do this even if the new process
499 will be detached, since we will need the process object and the
500 breakpoints to remove any breakpoints from memory when we
501 detach, and the client side will access registers. */
502 child_proc
= linux_add_process (new_pid
, 0);
503 gdb_assert (child_proc
!= NULL
);
504 child_lwp
= add_lwp (ptid
);
505 gdb_assert (child_lwp
!= NULL
);
506 child_lwp
->stopped
= 1;
507 child_lwp
->must_set_ptrace_flags
= 1;
508 child_lwp
->status_pending_p
= 0;
509 child_thr
= get_lwp_thread (child_lwp
);
510 child_thr
->last_resume_kind
= resume_stop
;
511 child_thr
->last_status
.kind
= TARGET_WAITKIND_STOPPED
;
513 /* If we're suspending all threads, leave this one suspended
515 if (stopping_threads
== STOPPING_AND_SUSPENDING_THREADS
)
518 debug_printf ("HEW: leaving child suspended\n");
519 child_lwp
->suspended
= 1;
522 parent_proc
= get_thread_process (event_thr
);
523 child_proc
->attached
= parent_proc
->attached
;
524 clone_all_breakpoints (&child_proc
->breakpoints
,
525 &child_proc
->raw_breakpoints
,
526 parent_proc
->breakpoints
);
528 tdesc
= XNEW (struct target_desc
);
529 copy_target_description (tdesc
, parent_proc
->tdesc
);
530 child_proc
->tdesc
= tdesc
;
532 /* Clone arch-specific process data. */
533 if (the_low_target
.new_fork
!= NULL
)
534 the_low_target
.new_fork (parent_proc
, child_proc
);
536 /* Save fork info in the parent thread. */
537 if (event
== PTRACE_EVENT_FORK
)
538 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_FORKED
;
539 else if (event
== PTRACE_EVENT_VFORK
)
540 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_VFORKED
;
542 event_lwp
->waitstatus
.value
.related_pid
= ptid
;
544 /* The status_pending field contains bits denoting the
545 extended event, so when the pending event is handled,
546 the handler will look at lwp->waitstatus. */
547 event_lwp
->status_pending_p
= 1;
548 event_lwp
->status_pending
= wstat
;
550 /* Report the event. */
555 debug_printf ("HEW: Got clone event "
556 "from LWP %ld, new child is LWP %ld\n",
557 lwpid_of (event_thr
), new_pid
);
559 ptid
= ptid_build (pid_of (event_thr
), new_pid
, 0);
560 new_lwp
= add_lwp (ptid
);
562 /* Either we're going to immediately resume the new thread
563 or leave it stopped. linux_resume_one_lwp is a nop if it
564 thinks the thread is currently running, so set this first
565 before calling linux_resume_one_lwp. */
566 new_lwp
->stopped
= 1;
568 /* If we're suspending all threads, leave this one suspended
570 if (stopping_threads
== STOPPING_AND_SUSPENDING_THREADS
)
571 new_lwp
->suspended
= 1;
573 /* Normally we will get the pending SIGSTOP. But in some cases
574 we might get another signal delivered to the group first.
575 If we do get another signal, be sure not to lose it. */
576 if (WSTOPSIG (status
) != SIGSTOP
)
578 new_lwp
->stop_expected
= 1;
579 new_lwp
->status_pending_p
= 1;
580 new_lwp
->status_pending
= status
;
582 else if (report_thread_events
)
584 new_lwp
->waitstatus
.kind
= TARGET_WAITKIND_THREAD_CREATED
;
585 new_lwp
->status_pending_p
= 1;
586 new_lwp
->status_pending
= status
;
589 /* Don't report the event. */
592 else if (event
== PTRACE_EVENT_VFORK_DONE
)
594 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_VFORK_DONE
;
596 /* Report the event. */
599 else if (event
== PTRACE_EVENT_EXEC
&& report_exec_events
)
601 struct process_info
*proc
;
607 debug_printf ("HEW: Got exec event from LWP %ld\n",
608 lwpid_of (event_thr
));
611 /* Get the event ptid. */
612 event_ptid
= ptid_of (event_thr
);
613 event_pid
= ptid_get_pid (event_ptid
);
615 /* Delete the execing process and all its threads. */
616 proc
= get_thread_process (event_thr
);
618 current_thread
= NULL
;
620 /* Create a new process/lwp/thread. */
621 proc
= linux_add_process (event_pid
, 0);
622 event_lwp
= add_lwp (event_ptid
);
623 event_thr
= get_lwp_thread (event_lwp
);
624 gdb_assert (current_thread
== event_thr
);
625 linux_arch_setup_thread (event_thr
);
627 /* Set the event status. */
628 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_EXECD
;
629 event_lwp
->waitstatus
.value
.execd_pathname
630 = xstrdup (linux_proc_pid_to_exec_file (lwpid_of (event_thr
)));
632 /* Mark the exec status as pending. */
633 event_lwp
->stopped
= 1;
634 event_lwp
->status_pending_p
= 1;
635 event_lwp
->status_pending
= wstat
;
636 event_thr
->last_resume_kind
= resume_continue
;
637 event_thr
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
639 /* Report the event. */
640 *orig_event_lwp
= event_lwp
;
644 internal_error (__FILE__
, __LINE__
, _("unknown ptrace event %d"), event
);
647 /* Return the PC as read from the regcache of LWP, without any
651 get_pc (struct lwp_info
*lwp
)
653 struct thread_info
*saved_thread
;
654 struct regcache
*regcache
;
657 if (the_low_target
.get_pc
== NULL
)
660 saved_thread
= current_thread
;
661 current_thread
= get_lwp_thread (lwp
);
663 regcache
= get_thread_regcache (current_thread
, 1);
664 pc
= (*the_low_target
.get_pc
) (regcache
);
667 debug_printf ("pc is 0x%lx\n", (long) pc
);
669 current_thread
= saved_thread
;
673 /* This function should only be called if LWP got a SIGTRAP.
674 The SIGTRAP could mean several things.
676 On i386, where decr_pc_after_break is non-zero:
678 If we were single-stepping this process using PTRACE_SINGLESTEP, we
679 will get only the one SIGTRAP. The value of $eip will be the next
680 instruction. If the instruction we stepped over was a breakpoint,
681 we need to decrement the PC.
683 If we continue the process using PTRACE_CONT, we will get a
684 SIGTRAP when we hit a breakpoint. The value of $eip will be
685 the instruction after the breakpoint (i.e. needs to be
686 decremented). If we report the SIGTRAP to GDB, we must also
687 report the undecremented PC. If the breakpoint is removed, we
688 must resume at the decremented PC.
690 On a non-decr_pc_after_break machine with hardware or kernel
693 If we either single-step a breakpoint instruction, or continue and
694 hit a breakpoint instruction, our PC will point at the breakpoint
698 check_stopped_by_breakpoint (struct lwp_info
*lwp
)
701 CORE_ADDR sw_breakpoint_pc
;
702 struct thread_info
*saved_thread
;
703 #if USE_SIGTRAP_SIGINFO
707 if (the_low_target
.get_pc
== NULL
)
711 sw_breakpoint_pc
= pc
- the_low_target
.decr_pc_after_break
;
713 /* breakpoint_at reads from the current thread. */
714 saved_thread
= current_thread
;
715 current_thread
= get_lwp_thread (lwp
);
717 #if USE_SIGTRAP_SIGINFO
718 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
719 (PTRACE_TYPE_ARG3
) 0, &siginfo
) == 0)
721 if (siginfo
.si_signo
== SIGTRAP
)
723 if (GDB_ARCH_IS_TRAP_BRKPT (siginfo
.si_code
))
727 struct thread_info
*thr
= get_lwp_thread (lwp
);
729 debug_printf ("CSBB: %s stopped by software breakpoint\n",
730 target_pid_to_str (ptid_of (thr
)));
733 /* Back up the PC if necessary. */
734 if (pc
!= sw_breakpoint_pc
)
736 struct regcache
*regcache
737 = get_thread_regcache (current_thread
, 1);
738 (*the_low_target
.set_pc
) (regcache
, sw_breakpoint_pc
);
741 lwp
->stop_pc
= sw_breakpoint_pc
;
742 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
743 current_thread
= saved_thread
;
746 else if (siginfo
.si_code
== TRAP_HWBKPT
)
750 struct thread_info
*thr
= get_lwp_thread (lwp
);
752 debug_printf ("CSBB: %s stopped by hardware "
753 "breakpoint/watchpoint\n",
754 target_pid_to_str (ptid_of (thr
)));
758 lwp
->stop_reason
= TARGET_STOPPED_BY_HW_BREAKPOINT
;
759 current_thread
= saved_thread
;
762 else if (siginfo
.si_code
== TRAP_TRACE
)
766 struct thread_info
*thr
= get_lwp_thread (lwp
);
768 debug_printf ("CSBB: %s stopped by trace\n",
769 target_pid_to_str (ptid_of (thr
)));
772 lwp
->stop_reason
= TARGET_STOPPED_BY_SINGLE_STEP
;
777 /* We may have just stepped a breakpoint instruction. E.g., in
778 non-stop mode, GDB first tells the thread A to step a range, and
779 then the user inserts a breakpoint inside the range. In that
780 case we need to report the breakpoint PC. */
781 if ((!lwp
->stepping
|| lwp
->stop_pc
== sw_breakpoint_pc
)
782 && (*the_low_target
.breakpoint_at
) (sw_breakpoint_pc
))
786 struct thread_info
*thr
= get_lwp_thread (lwp
);
788 debug_printf ("CSBB: %s stopped by software breakpoint\n",
789 target_pid_to_str (ptid_of (thr
)));
792 /* Back up the PC if necessary. */
793 if (pc
!= sw_breakpoint_pc
)
795 struct regcache
*regcache
796 = get_thread_regcache (current_thread
, 1);
797 (*the_low_target
.set_pc
) (regcache
, sw_breakpoint_pc
);
800 lwp
->stop_pc
= sw_breakpoint_pc
;
801 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
802 current_thread
= saved_thread
;
806 if (hardware_breakpoint_inserted_here (pc
))
810 struct thread_info
*thr
= get_lwp_thread (lwp
);
812 debug_printf ("CSBB: %s stopped by hardware breakpoint\n",
813 target_pid_to_str (ptid_of (thr
)));
817 lwp
->stop_reason
= TARGET_STOPPED_BY_HW_BREAKPOINT
;
818 current_thread
= saved_thread
;
823 current_thread
= saved_thread
;
827 static struct lwp_info
*
828 add_lwp (ptid_t ptid
)
830 struct lwp_info
*lwp
;
832 lwp
= XCNEW (struct lwp_info
);
834 lwp
->waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
836 if (the_low_target
.new_thread
!= NULL
)
837 the_low_target
.new_thread (lwp
);
839 lwp
->thread
= add_thread (ptid
, lwp
);
844 /* Start an inferior process and returns its pid.
845 ALLARGS is a vector of program-name and args. */
848 linux_create_inferior (char *program
, char **allargs
)
850 struct lwp_info
*new_lwp
;
853 struct cleanup
*restore_personality
854 = maybe_disable_address_space_randomization (disable_randomization
);
856 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
862 perror_with_name ("fork");
867 ptrace (PTRACE_TRACEME
, 0, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
869 #ifndef __ANDROID__ /* Bionic doesn't use SIGRTMIN the way glibc does. */
870 signal (__SIGRTMIN
+ 1, SIG_DFL
);
875 /* If gdbserver is connected to gdb via stdio, redirect the inferior's
876 stdout to stderr so that inferior i/o doesn't corrupt the connection.
877 Also, redirect stdin to /dev/null. */
878 if (remote_connection_is_stdio ())
881 open ("/dev/null", O_RDONLY
);
883 if (write (2, "stdin/stdout redirected\n",
884 sizeof ("stdin/stdout redirected\n") - 1) < 0)
886 /* Errors ignored. */;
890 execv (program
, allargs
);
892 execvp (program
, allargs
);
894 fprintf (stderr
, "Cannot exec %s: %s.\n", program
,
900 do_cleanups (restore_personality
);
902 linux_add_process (pid
, 0);
904 ptid
= ptid_build (pid
, pid
, 0);
905 new_lwp
= add_lwp (ptid
);
906 new_lwp
->must_set_ptrace_flags
= 1;
911 /* Attach to an inferior process. Returns 0 on success, ERRNO on
915 linux_attach_lwp (ptid_t ptid
)
917 struct lwp_info
*new_lwp
;
918 int lwpid
= ptid_get_lwp (ptid
);
920 if (ptrace (PTRACE_ATTACH
, lwpid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0)
924 new_lwp
= add_lwp (ptid
);
926 /* We need to wait for SIGSTOP before being able to make the next
927 ptrace call on this LWP. */
928 new_lwp
->must_set_ptrace_flags
= 1;
930 if (linux_proc_pid_is_stopped (lwpid
))
933 debug_printf ("Attached to a stopped process\n");
935 /* The process is definitely stopped. It is in a job control
936 stop, unless the kernel predates the TASK_STOPPED /
937 TASK_TRACED distinction, in which case it might be in a
938 ptrace stop. Make sure it is in a ptrace stop; from there we
939 can kill it, signal it, et cetera.
941 First make sure there is a pending SIGSTOP. Since we are
942 already attached, the process can not transition from stopped
943 to running without a PTRACE_CONT; so we know this signal will
944 go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
945 probably already in the queue (unless this kernel is old
946 enough to use TASK_STOPPED for ptrace stops); but since
947 SIGSTOP is not an RT signal, it can only be queued once. */
948 kill_lwp (lwpid
, SIGSTOP
);
950 /* Finally, resume the stopped process. This will deliver the
951 SIGSTOP (or a higher priority signal, just like normal
952 PTRACE_ATTACH), which we'll catch later on. */
953 ptrace (PTRACE_CONT
, lwpid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
956 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
959 There are several cases to consider here:
961 1) gdbserver has already attached to the process and is being notified
962 of a new thread that is being created.
963 In this case we should ignore that SIGSTOP and resume the
964 process. This is handled below by setting stop_expected = 1,
965 and the fact that add_thread sets last_resume_kind ==
968 2) This is the first thread (the process thread), and we're attaching
969 to it via attach_inferior.
970 In this case we want the process thread to stop.
971 This is handled by having linux_attach set last_resume_kind ==
972 resume_stop after we return.
974 If the pid we are attaching to is also the tgid, we attach to and
975 stop all the existing threads. Otherwise, we attach to pid and
976 ignore any other threads in the same group as this pid.
978 3) GDB is connecting to gdbserver and is requesting an enumeration of all
980 In this case we want the thread to stop.
981 FIXME: This case is currently not properly handled.
982 We should wait for the SIGSTOP but don't. Things work apparently
983 because enough time passes between when we ptrace (ATTACH) and when
984 gdb makes the next ptrace call on the thread.
986 On the other hand, if we are currently trying to stop all threads, we
987 should treat the new thread as if we had sent it a SIGSTOP. This works
988 because we are guaranteed that the add_lwp call above added us to the
989 end of the list, and so the new thread has not yet reached
990 wait_for_sigstop (but will). */
991 new_lwp
->stop_expected
= 1;
996 /* Callback for linux_proc_attach_tgid_threads. Attach to PTID if not
997 already attached. Returns true if a new LWP is found, false
1001 attach_proc_task_lwp_callback (ptid_t ptid
)
1003 /* Is this a new thread? */
1004 if (find_thread_ptid (ptid
) == NULL
)
1006 int lwpid
= ptid_get_lwp (ptid
);
1010 debug_printf ("Found new lwp %d\n", lwpid
);
1012 err
= linux_attach_lwp (ptid
);
1014 /* Be quiet if we simply raced with the thread exiting. EPERM
1015 is returned if the thread's task still exists, and is marked
1016 as exited or zombie, as well as other conditions, so in that
1017 case, confirm the status in /proc/PID/status. */
1019 || (err
== EPERM
&& linux_proc_pid_is_gone (lwpid
)))
1023 debug_printf ("Cannot attach to lwp %d: "
1024 "thread is gone (%d: %s)\n",
1025 lwpid
, err
, strerror (err
));
1030 warning (_("Cannot attach to lwp %d: %s"),
1032 linux_ptrace_attach_fail_reason_string (ptid
, err
));
1040 static void async_file_mark (void);
1042 /* Attach to PID. If PID is the tgid, attach to it and all
1046 linux_attach (unsigned long pid
)
1048 struct process_info
*proc
;
1049 struct thread_info
*initial_thread
;
1050 ptid_t ptid
= ptid_build (pid
, pid
, 0);
1053 /* Attach to PID. We will check for other threads
1055 err
= linux_attach_lwp (ptid
);
1057 error ("Cannot attach to process %ld: %s",
1058 pid
, linux_ptrace_attach_fail_reason_string (ptid
, err
));
1060 proc
= linux_add_process (pid
, 1);
1062 /* Don't ignore the initial SIGSTOP if we just attached to this
1063 process. It will be collected by wait shortly. */
1064 initial_thread
= find_thread_ptid (ptid_build (pid
, pid
, 0));
1065 initial_thread
->last_resume_kind
= resume_stop
;
1067 /* We must attach to every LWP. If /proc is mounted, use that to
1068 find them now. On the one hand, the inferior may be using raw
1069 clone instead of using pthreads. On the other hand, even if it
1070 is using pthreads, GDB may not be connected yet (thread_db needs
1071 to do symbol lookups, through qSymbol). Also, thread_db walks
1072 structures in the inferior's address space to find the list of
1073 threads/LWPs, and those structures may well be corrupted. Note
1074 that once thread_db is loaded, we'll still use it to list threads
1075 and associate pthread info with each LWP. */
1076 linux_proc_attach_tgid_threads (pid
, attach_proc_task_lwp_callback
);
1078 /* GDB will shortly read the xml target description for this
1079 process, to figure out the process' architecture. But the target
1080 description is only filled in when the first process/thread in
1081 the thread group reports its initial PTRACE_ATTACH SIGSTOP. Do
1082 that now, otherwise, if GDB is fast enough, it could read the
1083 target description _before_ that initial stop. */
1086 struct lwp_info
*lwp
;
1088 ptid_t pid_ptid
= pid_to_ptid (pid
);
1090 lwpid
= linux_wait_for_event_filtered (pid_ptid
, pid_ptid
,
1092 gdb_assert (lwpid
> 0);
1094 lwp
= find_lwp_pid (pid_to_ptid (lwpid
));
1096 if (!WIFSTOPPED (wstat
) || WSTOPSIG (wstat
) != SIGSTOP
)
1098 lwp
->status_pending_p
= 1;
1099 lwp
->status_pending
= wstat
;
1102 initial_thread
->last_resume_kind
= resume_continue
;
1106 gdb_assert (proc
->tdesc
!= NULL
);
1119 second_thread_of_pid_p (struct inferior_list_entry
*entry
, void *args
)
1121 struct counter
*counter
= (struct counter
*) args
;
1123 if (ptid_get_pid (entry
->id
) == counter
->pid
)
1125 if (++counter
->count
> 1)
1133 last_thread_of_process_p (int pid
)
1135 struct counter counter
= { pid
, 0 };
1137 return (find_inferior (&all_threads
,
1138 second_thread_of_pid_p
, &counter
) == NULL
);
1144 linux_kill_one_lwp (struct lwp_info
*lwp
)
1146 struct thread_info
*thr
= get_lwp_thread (lwp
);
1147 int pid
= lwpid_of (thr
);
1149 /* PTRACE_KILL is unreliable. After stepping into a signal handler,
1150 there is no signal context, and ptrace(PTRACE_KILL) (or
1151 ptrace(PTRACE_CONT, SIGKILL), pretty much the same) acts like
1152 ptrace(CONT, pid, 0,0) and just resumes the tracee. A better
1153 alternative is to kill with SIGKILL. We only need one SIGKILL
1154 per process, not one for each thread. But since we still support
1155 linuxthreads, and we also support debugging programs using raw
1156 clone without CLONE_THREAD, we send one for each thread. For
1157 years, we used PTRACE_KILL only, so we're being a bit paranoid
1158 about some old kernels where PTRACE_KILL might work better
1159 (dubious if there are any such, but that's why it's paranoia), so
1160 we try SIGKILL first, PTRACE_KILL second, and so we're fine
1164 kill_lwp (pid
, SIGKILL
);
1167 int save_errno
= errno
;
1169 debug_printf ("LKL: kill_lwp (SIGKILL) %s, 0, 0 (%s)\n",
1170 target_pid_to_str (ptid_of (thr
)),
1171 save_errno
? strerror (save_errno
) : "OK");
1175 ptrace (PTRACE_KILL
, pid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
1178 int save_errno
= errno
;
1180 debug_printf ("LKL: PTRACE_KILL %s, 0, 0 (%s)\n",
1181 target_pid_to_str (ptid_of (thr
)),
1182 save_errno
? strerror (save_errno
) : "OK");
1186 /* Kill LWP and wait for it to die. */
1189 kill_wait_lwp (struct lwp_info
*lwp
)
1191 struct thread_info
*thr
= get_lwp_thread (lwp
);
1192 int pid
= ptid_get_pid (ptid_of (thr
));
1193 int lwpid
= ptid_get_lwp (ptid_of (thr
));
1198 debug_printf ("kwl: killing lwp %d, for pid: %d\n", lwpid
, pid
);
1202 linux_kill_one_lwp (lwp
);
1204 /* Make sure it died. Notes:
1206 - The loop is most likely unnecessary.
1208 - We don't use linux_wait_for_event as that could delete lwps
1209 while we're iterating over them. We're not interested in
1210 any pending status at this point, only in making sure all
1211 wait status on the kernel side are collected until the
1214 - We don't use __WALL here as the __WALL emulation relies on
1215 SIGCHLD, and killing a stopped process doesn't generate
1216 one, nor an exit status.
1218 res
= my_waitpid (lwpid
, &wstat
, 0);
1219 if (res
== -1 && errno
== ECHILD
)
1220 res
= my_waitpid (lwpid
, &wstat
, __WCLONE
);
1221 } while (res
> 0 && WIFSTOPPED (wstat
));
1223 /* Even if it was stopped, the child may have already disappeared.
1224 E.g., if it was killed by SIGKILL. */
1225 if (res
< 0 && errno
!= ECHILD
)
1226 perror_with_name ("kill_wait_lwp");
1229 /* Callback for `find_inferior'. Kills an lwp of a given process,
1230 except the leader. */
1233 kill_one_lwp_callback (struct inferior_list_entry
*entry
, void *args
)
1235 struct thread_info
*thread
= (struct thread_info
*) entry
;
1236 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1237 int pid
= * (int *) args
;
1239 if (ptid_get_pid (entry
->id
) != pid
)
1242 /* We avoid killing the first thread here, because of a Linux kernel (at
1243 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
1244 the children get a chance to be reaped, it will remain a zombie
1247 if (lwpid_of (thread
) == pid
)
1250 debug_printf ("lkop: is last of process %s\n",
1251 target_pid_to_str (entry
->id
));
1255 kill_wait_lwp (lwp
);
1260 linux_kill (int pid
)
1262 struct process_info
*process
;
1263 struct lwp_info
*lwp
;
1265 process
= find_process_pid (pid
);
1266 if (process
== NULL
)
1269 /* If we're killing a running inferior, make sure it is stopped
1270 first, as PTRACE_KILL will not work otherwise. */
1271 stop_all_lwps (0, NULL
);
1273 find_inferior (&all_threads
, kill_one_lwp_callback
, &pid
);
1275 /* See the comment in linux_kill_one_lwp. We did not kill the first
1276 thread in the list, so do so now. */
1277 lwp
= find_lwp_pid (pid_to_ptid (pid
));
1282 debug_printf ("lk_1: cannot find lwp for pid: %d\n",
1286 kill_wait_lwp (lwp
);
1288 the_target
->mourn (process
);
1290 /* Since we presently can only stop all lwps of all processes, we
1291 need to unstop lwps of other processes. */
1292 unstop_all_lwps (0, NULL
);
1296 /* Get pending signal of THREAD, for detaching purposes. This is the
1297 signal the thread last stopped for, which we need to deliver to the
1298 thread when detaching, otherwise, it'd be suppressed/lost. */
1301 get_detach_signal (struct thread_info
*thread
)
1303 enum gdb_signal signo
= GDB_SIGNAL_0
;
1305 struct lwp_info
*lp
= get_thread_lwp (thread
);
1307 if (lp
->status_pending_p
)
1308 status
= lp
->status_pending
;
1311 /* If the thread had been suspended by gdbserver, and it stopped
1312 cleanly, then it'll have stopped with SIGSTOP. But we don't
1313 want to deliver that SIGSTOP. */
1314 if (thread
->last_status
.kind
!= TARGET_WAITKIND_STOPPED
1315 || thread
->last_status
.value
.sig
== GDB_SIGNAL_0
)
1318 /* Otherwise, we may need to deliver the signal we
1320 status
= lp
->last_status
;
1323 if (!WIFSTOPPED (status
))
1326 debug_printf ("GPS: lwp %s hasn't stopped: no pending signal\n",
1327 target_pid_to_str (ptid_of (thread
)));
1331 /* Extended wait statuses aren't real SIGTRAPs. */
1332 if (WSTOPSIG (status
) == SIGTRAP
&& linux_is_extended_waitstatus (status
))
1335 debug_printf ("GPS: lwp %s had stopped with extended "
1336 "status: no pending signal\n",
1337 target_pid_to_str (ptid_of (thread
)));
1341 signo
= gdb_signal_from_host (WSTOPSIG (status
));
1343 if (program_signals_p
&& !program_signals
[signo
])
1346 debug_printf ("GPS: lwp %s had signal %s, but it is in nopass state\n",
1347 target_pid_to_str (ptid_of (thread
)),
1348 gdb_signal_to_string (signo
));
1351 else if (!program_signals_p
1352 /* If we have no way to know which signals GDB does not
1353 want to have passed to the program, assume
1354 SIGTRAP/SIGINT, which is GDB's default. */
1355 && (signo
== GDB_SIGNAL_TRAP
|| signo
== GDB_SIGNAL_INT
))
1358 debug_printf ("GPS: lwp %s had signal %s, "
1359 "but we don't know if we should pass it. "
1360 "Default to not.\n",
1361 target_pid_to_str (ptid_of (thread
)),
1362 gdb_signal_to_string (signo
));
1368 debug_printf ("GPS: lwp %s has pending signal %s: delivering it.\n",
1369 target_pid_to_str (ptid_of (thread
)),
1370 gdb_signal_to_string (signo
));
1372 return WSTOPSIG (status
);
1377 linux_detach_one_lwp (struct inferior_list_entry
*entry
, void *args
)
1379 struct thread_info
*thread
= (struct thread_info
*) entry
;
1380 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1381 int pid
= * (int *) args
;
1384 if (ptid_get_pid (entry
->id
) != pid
)
1387 /* If there is a pending SIGSTOP, get rid of it. */
1388 if (lwp
->stop_expected
)
1391 debug_printf ("Sending SIGCONT to %s\n",
1392 target_pid_to_str (ptid_of (thread
)));
1394 kill_lwp (lwpid_of (thread
), SIGCONT
);
1395 lwp
->stop_expected
= 0;
1398 /* Flush any pending changes to the process's registers. */
1399 regcache_invalidate_thread (thread
);
1401 /* Pass on any pending signal for this thread. */
1402 sig
= get_detach_signal (thread
);
1404 /* Finally, let it resume. */
1405 if (the_low_target
.prepare_to_resume
!= NULL
)
1406 the_low_target
.prepare_to_resume (lwp
);
1407 if (ptrace (PTRACE_DETACH
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
1408 (PTRACE_TYPE_ARG4
) (long) sig
) < 0)
1409 error (_("Can't detach %s: %s"),
1410 target_pid_to_str (ptid_of (thread
)),
1418 linux_detach (int pid
)
1420 struct process_info
*process
;
1422 process
= find_process_pid (pid
);
1423 if (process
== NULL
)
1426 /* As there's a step over already in progress, let it finish first,
1427 otherwise nesting a stabilize_threads operation on top gets real
1429 complete_ongoing_step_over ();
1431 /* Stop all threads before detaching. First, ptrace requires that
1432 the thread is stopped to sucessfully detach. Second, thread_db
1433 may need to uninstall thread event breakpoints from memory, which
1434 only works with a stopped process anyway. */
1435 stop_all_lwps (0, NULL
);
1437 #ifdef USE_THREAD_DB
1438 thread_db_detach (process
);
1441 /* Stabilize threads (move out of jump pads). */
1442 stabilize_threads ();
1444 find_inferior (&all_threads
, linux_detach_one_lwp
, &pid
);
1446 the_target
->mourn (process
);
1448 /* Since we presently can only stop all lwps of all processes, we
1449 need to unstop lwps of other processes. */
1450 unstop_all_lwps (0, NULL
);
1454 /* Remove all LWPs that belong to process PROC from the lwp list. */
1457 delete_lwp_callback (struct inferior_list_entry
*entry
, void *proc
)
1459 struct thread_info
*thread
= (struct thread_info
*) entry
;
1460 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1461 struct process_info
*process
= (struct process_info
*) proc
;
1463 if (pid_of (thread
) == pid_of (process
))
1470 linux_mourn (struct process_info
*process
)
1472 struct process_info_private
*priv
;
1474 #ifdef USE_THREAD_DB
1475 thread_db_mourn (process
);
1478 find_inferior (&all_threads
, delete_lwp_callback
, process
);
1480 /* Freeing all private data. */
1481 priv
= process
->priv
;
1482 free (priv
->arch_private
);
1484 process
->priv
= NULL
;
1486 remove_process (process
);
1490 linux_join (int pid
)
1495 ret
= my_waitpid (pid
, &status
, 0);
1496 if (WIFEXITED (status
) || WIFSIGNALED (status
))
1498 } while (ret
!= -1 || errno
!= ECHILD
);
1501 /* Return nonzero if the given thread is still alive. */
1503 linux_thread_alive (ptid_t ptid
)
1505 struct lwp_info
*lwp
= find_lwp_pid (ptid
);
1507 /* We assume we always know if a thread exits. If a whole process
1508 exited but we still haven't been able to report it to GDB, we'll
1509 hold on to the last lwp of the dead process. */
1511 return !lwp_is_marked_dead (lwp
);
1516 /* Return 1 if this lwp still has an interesting status pending. If
1517 not (e.g., it had stopped for a breakpoint that is gone), return
1521 thread_still_has_status_pending_p (struct thread_info
*thread
)
1523 struct lwp_info
*lp
= get_thread_lwp (thread
);
1525 if (!lp
->status_pending_p
)
1528 if (thread
->last_resume_kind
!= resume_stop
1529 && (lp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
1530 || lp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
1532 struct thread_info
*saved_thread
;
1536 gdb_assert (lp
->last_status
!= 0);
1540 saved_thread
= current_thread
;
1541 current_thread
= thread
;
1543 if (pc
!= lp
->stop_pc
)
1546 debug_printf ("PC of %ld changed\n",
1551 #if !USE_SIGTRAP_SIGINFO
1552 else if (lp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
1553 && !(*the_low_target
.breakpoint_at
) (pc
))
1556 debug_printf ("previous SW breakpoint of %ld gone\n",
1560 else if (lp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
1561 && !hardware_breakpoint_inserted_here (pc
))
1564 debug_printf ("previous HW breakpoint of %ld gone\n",
1570 current_thread
= saved_thread
;
1575 debug_printf ("discarding pending breakpoint status\n");
1576 lp
->status_pending_p
= 0;
1584 /* Returns true if LWP is resumed from the client's perspective. */
1587 lwp_resumed (struct lwp_info
*lwp
)
1589 struct thread_info
*thread
= get_lwp_thread (lwp
);
1591 if (thread
->last_resume_kind
!= resume_stop
)
1594 /* Did gdb send us a `vCont;t', but we haven't reported the
1595 corresponding stop to gdb yet? If so, the thread is still
1596 resumed/running from gdb's perspective. */
1597 if (thread
->last_resume_kind
== resume_stop
1598 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
)
1604 /* Return 1 if this lwp has an interesting status pending. */
1606 status_pending_p_callback (struct inferior_list_entry
*entry
, void *arg
)
1608 struct thread_info
*thread
= (struct thread_info
*) entry
;
1609 struct lwp_info
*lp
= get_thread_lwp (thread
);
1610 ptid_t ptid
= * (ptid_t
*) arg
;
1612 /* Check if we're only interested in events from a specific process
1613 or a specific LWP. */
1614 if (!ptid_match (ptid_of (thread
), ptid
))
1617 if (!lwp_resumed (lp
))
1620 if (lp
->status_pending_p
1621 && !thread_still_has_status_pending_p (thread
))
1623 linux_resume_one_lwp (lp
, lp
->stepping
, GDB_SIGNAL_0
, NULL
);
1627 return lp
->status_pending_p
;
1631 same_lwp (struct inferior_list_entry
*entry
, void *data
)
1633 ptid_t ptid
= *(ptid_t
*) data
;
1636 if (ptid_get_lwp (ptid
) != 0)
1637 lwp
= ptid_get_lwp (ptid
);
1639 lwp
= ptid_get_pid (ptid
);
1641 if (ptid_get_lwp (entry
->id
) == lwp
)
1648 find_lwp_pid (ptid_t ptid
)
1650 struct inferior_list_entry
*thread
1651 = find_inferior (&all_threads
, same_lwp
, &ptid
);
1656 return get_thread_lwp ((struct thread_info
*) thread
);
1659 /* Return the number of known LWPs in the tgid given by PID. */
1664 struct inferior_list_entry
*inf
, *tmp
;
1667 ALL_INFERIORS (&all_threads
, inf
, tmp
)
1669 if (ptid_get_pid (inf
->id
) == pid
)
1676 /* The arguments passed to iterate_over_lwps. */
1678 struct iterate_over_lwps_args
1680 /* The FILTER argument passed to iterate_over_lwps. */
1683 /* The CALLBACK argument passed to iterate_over_lwps. */
1684 iterate_over_lwps_ftype
*callback
;
1686 /* The DATA argument passed to iterate_over_lwps. */
1690 /* Callback for find_inferior used by iterate_over_lwps to filter
1691 calls to the callback supplied to that function. Returning a
1692 nonzero value causes find_inferiors to stop iterating and return
1693 the current inferior_list_entry. Returning zero indicates that
1694 find_inferiors should continue iterating. */
1697 iterate_over_lwps_filter (struct inferior_list_entry
*entry
, void *args_p
)
1699 struct iterate_over_lwps_args
*args
1700 = (struct iterate_over_lwps_args
*) args_p
;
1702 if (ptid_match (entry
->id
, args
->filter
))
1704 struct thread_info
*thr
= (struct thread_info
*) entry
;
1705 struct lwp_info
*lwp
= get_thread_lwp (thr
);
1707 return (*args
->callback
) (lwp
, args
->data
);
1713 /* See nat/linux-nat.h. */
1716 iterate_over_lwps (ptid_t filter
,
1717 iterate_over_lwps_ftype callback
,
1720 struct iterate_over_lwps_args args
= {filter
, callback
, data
};
1721 struct inferior_list_entry
*entry
;
1723 entry
= find_inferior (&all_threads
, iterate_over_lwps_filter
, &args
);
1727 return get_thread_lwp ((struct thread_info
*) entry
);
1730 /* Detect zombie thread group leaders, and "exit" them. We can't reap
1731 their exits until all other threads in the group have exited. */
1734 check_zombie_leaders (void)
1736 struct process_info
*proc
, *tmp
;
1738 ALL_PROCESSES (proc
, tmp
)
1740 pid_t leader_pid
= pid_of (proc
);
1741 struct lwp_info
*leader_lp
;
1743 leader_lp
= find_lwp_pid (pid_to_ptid (leader_pid
));
1746 debug_printf ("leader_pid=%d, leader_lp!=NULL=%d, "
1747 "num_lwps=%d, zombie=%d\n",
1748 leader_pid
, leader_lp
!= NULL
, num_lwps (leader_pid
),
1749 linux_proc_pid_is_zombie (leader_pid
));
1751 if (leader_lp
!= NULL
&& !leader_lp
->stopped
1752 /* Check if there are other threads in the group, as we may
1753 have raced with the inferior simply exiting. */
1754 && !last_thread_of_process_p (leader_pid
)
1755 && linux_proc_pid_is_zombie (leader_pid
))
1757 /* A leader zombie can mean one of two things:
1759 - It exited, and there's an exit status pending
1760 available, or only the leader exited (not the whole
1761 program). In the latter case, we can't waitpid the
1762 leader's exit status until all other threads are gone.
1764 - There are 3 or more threads in the group, and a thread
1765 other than the leader exec'd. On an exec, the Linux
1766 kernel destroys all other threads (except the execing
1767 one) in the thread group, and resets the execing thread's
1768 tid to the tgid. No exit notification is sent for the
1769 execing thread -- from the ptracer's perspective, it
1770 appears as though the execing thread just vanishes.
1771 Until we reap all other threads except the leader and the
1772 execing thread, the leader will be zombie, and the
1773 execing thread will be in `D (disc sleep)'. As soon as
1774 all other threads are reaped, the execing thread changes
1775 it's tid to the tgid, and the previous (zombie) leader
1776 vanishes, giving place to the "new" leader. We could try
1777 distinguishing the exit and exec cases, by waiting once
1778 more, and seeing if something comes out, but it doesn't
1779 sound useful. The previous leader _does_ go away, and
1780 we'll re-add the new one once we see the exec event
1781 (which is just the same as what would happen if the
1782 previous leader did exit voluntarily before some other
1787 "CZL: Thread group leader %d zombie "
1788 "(it exited, or another thread execd).\n",
1791 delete_lwp (leader_lp
);
1796 /* Callback for `find_inferior'. Returns the first LWP that is not
1797 stopped. ARG is a PTID filter. */
1800 not_stopped_callback (struct inferior_list_entry
*entry
, void *arg
)
1802 struct thread_info
*thr
= (struct thread_info
*) entry
;
1803 struct lwp_info
*lwp
;
1804 ptid_t filter
= *(ptid_t
*) arg
;
1806 if (!ptid_match (ptid_of (thr
), filter
))
1809 lwp
= get_thread_lwp (thr
);
1816 /* Increment LWP's suspend count. */
1819 lwp_suspended_inc (struct lwp_info
*lwp
)
1823 if (debug_threads
&& lwp
->suspended
> 4)
1825 struct thread_info
*thread
= get_lwp_thread (lwp
);
1827 debug_printf ("LWP %ld has a suspiciously high suspend count,"
1828 " suspended=%d\n", lwpid_of (thread
), lwp
->suspended
);
1832 /* Decrement LWP's suspend count. */
1835 lwp_suspended_decr (struct lwp_info
*lwp
)
1839 if (lwp
->suspended
< 0)
1841 struct thread_info
*thread
= get_lwp_thread (lwp
);
1843 internal_error (__FILE__
, __LINE__
,
1844 "unsuspend LWP %ld, suspended=%d\n", lwpid_of (thread
),
1849 /* This function should only be called if the LWP got a SIGTRAP.
1851 Handle any tracepoint steps or hits. Return true if a tracepoint
1852 event was handled, 0 otherwise. */
1855 handle_tracepoints (struct lwp_info
*lwp
)
1857 struct thread_info
*tinfo
= get_lwp_thread (lwp
);
1858 int tpoint_related_event
= 0;
1860 gdb_assert (lwp
->suspended
== 0);
1862 /* If this tracepoint hit causes a tracing stop, we'll immediately
1863 uninsert tracepoints. To do this, we temporarily pause all
1864 threads, unpatch away, and then unpause threads. We need to make
1865 sure the unpausing doesn't resume LWP too. */
1866 lwp_suspended_inc (lwp
);
1868 /* And we need to be sure that any all-threads-stopping doesn't try
1869 to move threads out of the jump pads, as it could deadlock the
1870 inferior (LWP could be in the jump pad, maybe even holding the
1873 /* Do any necessary step collect actions. */
1874 tpoint_related_event
|= tracepoint_finished_step (tinfo
, lwp
->stop_pc
);
1876 tpoint_related_event
|= handle_tracepoint_bkpts (tinfo
, lwp
->stop_pc
);
1878 /* See if we just hit a tracepoint and do its main collect
1880 tpoint_related_event
|= tracepoint_was_hit (tinfo
, lwp
->stop_pc
);
1882 lwp_suspended_decr (lwp
);
1884 gdb_assert (lwp
->suspended
== 0);
1885 gdb_assert (!stabilizing_threads
|| lwp
->collecting_fast_tracepoint
);
1887 if (tpoint_related_event
)
1890 debug_printf ("got a tracepoint event\n");
1897 /* Convenience wrapper. Returns true if LWP is presently collecting a
1901 linux_fast_tracepoint_collecting (struct lwp_info
*lwp
,
1902 struct fast_tpoint_collect_status
*status
)
1904 CORE_ADDR thread_area
;
1905 struct thread_info
*thread
= get_lwp_thread (lwp
);
1907 if (the_low_target
.get_thread_area
== NULL
)
1910 /* Get the thread area address. This is used to recognize which
1911 thread is which when tracing with the in-process agent library.
1912 We don't read anything from the address, and treat it as opaque;
1913 it's the address itself that we assume is unique per-thread. */
1914 if ((*the_low_target
.get_thread_area
) (lwpid_of (thread
), &thread_area
) == -1)
1917 return fast_tracepoint_collecting (thread_area
, lwp
->stop_pc
, status
);
1920 /* The reason we resume in the caller, is because we want to be able
1921 to pass lwp->status_pending as WSTAT, and we need to clear
1922 status_pending_p before resuming, otherwise, linux_resume_one_lwp
1923 refuses to resume. */
1926 maybe_move_out_of_jump_pad (struct lwp_info
*lwp
, int *wstat
)
1928 struct thread_info
*saved_thread
;
1930 saved_thread
= current_thread
;
1931 current_thread
= get_lwp_thread (lwp
);
1934 || (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) != SIGTRAP
))
1935 && supports_fast_tracepoints ()
1936 && agent_loaded_p ())
1938 struct fast_tpoint_collect_status status
;
1942 debug_printf ("Checking whether LWP %ld needs to move out of the "
1944 lwpid_of (current_thread
));
1946 r
= linux_fast_tracepoint_collecting (lwp
, &status
);
1949 || (WSTOPSIG (*wstat
) != SIGILL
1950 && WSTOPSIG (*wstat
) != SIGFPE
1951 && WSTOPSIG (*wstat
) != SIGSEGV
1952 && WSTOPSIG (*wstat
) != SIGBUS
))
1954 lwp
->collecting_fast_tracepoint
= r
;
1958 if (r
== 1 && lwp
->exit_jump_pad_bkpt
== NULL
)
1960 /* Haven't executed the original instruction yet.
1961 Set breakpoint there, and wait till it's hit,
1962 then single-step until exiting the jump pad. */
1963 lwp
->exit_jump_pad_bkpt
1964 = set_breakpoint_at (status
.adjusted_insn_addr
, NULL
);
1968 debug_printf ("Checking whether LWP %ld needs to move out of "
1969 "the jump pad...it does\n",
1970 lwpid_of (current_thread
));
1971 current_thread
= saved_thread
;
1978 /* If we get a synchronous signal while collecting, *and*
1979 while executing the (relocated) original instruction,
1980 reset the PC to point at the tpoint address, before
1981 reporting to GDB. Otherwise, it's an IPA lib bug: just
1982 report the signal to GDB, and pray for the best. */
1984 lwp
->collecting_fast_tracepoint
= 0;
1987 && (status
.adjusted_insn_addr
<= lwp
->stop_pc
1988 && lwp
->stop_pc
< status
.adjusted_insn_addr_end
))
1991 struct regcache
*regcache
;
1993 /* The si_addr on a few signals references the address
1994 of the faulting instruction. Adjust that as
1996 if ((WSTOPSIG (*wstat
) == SIGILL
1997 || WSTOPSIG (*wstat
) == SIGFPE
1998 || WSTOPSIG (*wstat
) == SIGBUS
1999 || WSTOPSIG (*wstat
) == SIGSEGV
)
2000 && ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
2001 (PTRACE_TYPE_ARG3
) 0, &info
) == 0
2002 /* Final check just to make sure we don't clobber
2003 the siginfo of non-kernel-sent signals. */
2004 && (uintptr_t) info
.si_addr
== lwp
->stop_pc
)
2006 info
.si_addr
= (void *) (uintptr_t) status
.tpoint_addr
;
2007 ptrace (PTRACE_SETSIGINFO
, lwpid_of (current_thread
),
2008 (PTRACE_TYPE_ARG3
) 0, &info
);
2011 regcache
= get_thread_regcache (current_thread
, 1);
2012 (*the_low_target
.set_pc
) (regcache
, status
.tpoint_addr
);
2013 lwp
->stop_pc
= status
.tpoint_addr
;
2015 /* Cancel any fast tracepoint lock this thread was
2017 force_unlock_trace_buffer ();
2020 if (lwp
->exit_jump_pad_bkpt
!= NULL
)
2023 debug_printf ("Cancelling fast exit-jump-pad: removing bkpt. "
2024 "stopping all threads momentarily.\n");
2026 stop_all_lwps (1, lwp
);
2028 delete_breakpoint (lwp
->exit_jump_pad_bkpt
);
2029 lwp
->exit_jump_pad_bkpt
= NULL
;
2031 unstop_all_lwps (1, lwp
);
2033 gdb_assert (lwp
->suspended
>= 0);
2039 debug_printf ("Checking whether LWP %ld needs to move out of the "
2041 lwpid_of (current_thread
));
2043 current_thread
= saved_thread
;
2047 /* Enqueue one signal in the "signals to report later when out of the
2051 enqueue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
2053 struct pending_signals
*p_sig
;
2054 struct thread_info
*thread
= get_lwp_thread (lwp
);
2057 debug_printf ("Deferring signal %d for LWP %ld.\n",
2058 WSTOPSIG (*wstat
), lwpid_of (thread
));
2062 struct pending_signals
*sig
;
2064 for (sig
= lwp
->pending_signals_to_report
;
2067 debug_printf (" Already queued %d\n",
2070 debug_printf (" (no more currently queued signals)\n");
2073 /* Don't enqueue non-RT signals if they are already in the deferred
2074 queue. (SIGSTOP being the easiest signal to see ending up here
2076 if (WSTOPSIG (*wstat
) < __SIGRTMIN
)
2078 struct pending_signals
*sig
;
2080 for (sig
= lwp
->pending_signals_to_report
;
2084 if (sig
->signal
== WSTOPSIG (*wstat
))
2087 debug_printf ("Not requeuing already queued non-RT signal %d"
2096 p_sig
= XCNEW (struct pending_signals
);
2097 p_sig
->prev
= lwp
->pending_signals_to_report
;
2098 p_sig
->signal
= WSTOPSIG (*wstat
);
2100 ptrace (PTRACE_GETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
2103 lwp
->pending_signals_to_report
= p_sig
;
2106 /* Dequeue one signal from the "signals to report later when out of
2107 the jump pad" list. */
2110 dequeue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
2112 struct thread_info
*thread
= get_lwp_thread (lwp
);
2114 if (lwp
->pending_signals_to_report
!= NULL
)
2116 struct pending_signals
**p_sig
;
2118 p_sig
= &lwp
->pending_signals_to_report
;
2119 while ((*p_sig
)->prev
!= NULL
)
2120 p_sig
= &(*p_sig
)->prev
;
2122 *wstat
= W_STOPCODE ((*p_sig
)->signal
);
2123 if ((*p_sig
)->info
.si_signo
!= 0)
2124 ptrace (PTRACE_SETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
2130 debug_printf ("Reporting deferred signal %d for LWP %ld.\n",
2131 WSTOPSIG (*wstat
), lwpid_of (thread
));
2135 struct pending_signals
*sig
;
2137 for (sig
= lwp
->pending_signals_to_report
;
2140 debug_printf (" Still queued %d\n",
2143 debug_printf (" (no more queued signals)\n");
2152 /* Fetch the possibly triggered data watchpoint info and store it in
2155 On some archs, like x86, that use debug registers to set
2156 watchpoints, it's possible that the way to know which watched
2157 address trapped, is to check the register that is used to select
2158 which address to watch. Problem is, between setting the watchpoint
2159 and reading back which data address trapped, the user may change
2160 the set of watchpoints, and, as a consequence, GDB changes the
2161 debug registers in the inferior. To avoid reading back a stale
2162 stopped-data-address when that happens, we cache in LP the fact
2163 that a watchpoint trapped, and the corresponding data address, as
2164 soon as we see CHILD stop with a SIGTRAP. If GDB changes the debug
2165 registers meanwhile, we have the cached data we can rely on. */
2168 check_stopped_by_watchpoint (struct lwp_info
*child
)
2170 if (the_low_target
.stopped_by_watchpoint
!= NULL
)
2172 struct thread_info
*saved_thread
;
2174 saved_thread
= current_thread
;
2175 current_thread
= get_lwp_thread (child
);
2177 if (the_low_target
.stopped_by_watchpoint ())
2179 child
->stop_reason
= TARGET_STOPPED_BY_WATCHPOINT
;
2181 if (the_low_target
.stopped_data_address
!= NULL
)
2182 child
->stopped_data_address
2183 = the_low_target
.stopped_data_address ();
2185 child
->stopped_data_address
= 0;
2188 current_thread
= saved_thread
;
2191 return child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
;
2194 /* Return the ptrace options that we want to try to enable. */
2197 linux_low_ptrace_options (int attached
)
2202 options
|= PTRACE_O_EXITKILL
;
2204 if (report_fork_events
)
2205 options
|= PTRACE_O_TRACEFORK
;
2207 if (report_vfork_events
)
2208 options
|= (PTRACE_O_TRACEVFORK
| PTRACE_O_TRACEVFORKDONE
);
2210 if (report_exec_events
)
2211 options
|= PTRACE_O_TRACEEXEC
;
2216 /* Do low-level handling of the event, and check if we should go on
2217 and pass it to caller code. Return the affected lwp if we are, or
2220 static struct lwp_info
*
2221 linux_low_filter_event (int lwpid
, int wstat
)
2223 struct lwp_info
*child
;
2224 struct thread_info
*thread
;
2225 int have_stop_pc
= 0;
2227 child
= find_lwp_pid (pid_to_ptid (lwpid
));
2229 /* Check for stop events reported by a process we didn't already
2230 know about - anything not already in our LWP list.
2232 If we're expecting to receive stopped processes after
2233 fork, vfork, and clone events, then we'll just add the
2234 new one to our list and go back to waiting for the event
2235 to be reported - the stopped process might be returned
2236 from waitpid before or after the event is.
2238 But note the case of a non-leader thread exec'ing after the
2239 leader having exited, and gone from our lists (because
2240 check_zombie_leaders deleted it). The non-leader thread
2241 changes its tid to the tgid. */
2243 if (WIFSTOPPED (wstat
) && child
== NULL
&& WSTOPSIG (wstat
) == SIGTRAP
2244 && linux_ptrace_get_extended_event (wstat
) == PTRACE_EVENT_EXEC
)
2248 /* A multi-thread exec after we had seen the leader exiting. */
2251 debug_printf ("LLW: Re-adding thread group leader LWP %d"
2252 "after exec.\n", lwpid
);
2255 child_ptid
= ptid_build (lwpid
, lwpid
, 0);
2256 child
= add_lwp (child_ptid
);
2258 current_thread
= child
->thread
;
2261 /* If we didn't find a process, one of two things presumably happened:
2262 - A process we started and then detached from has exited. Ignore it.
2263 - A process we are controlling has forked and the new child's stop
2264 was reported to us by the kernel. Save its PID. */
2265 if (child
== NULL
&& WIFSTOPPED (wstat
))
2267 add_to_pid_list (&stopped_pids
, lwpid
, wstat
);
2270 else if (child
== NULL
)
2273 thread
= get_lwp_thread (child
);
2277 child
->last_status
= wstat
;
2279 /* Check if the thread has exited. */
2280 if ((WIFEXITED (wstat
) || WIFSIGNALED (wstat
)))
2283 debug_printf ("LLFE: %d exited.\n", lwpid
);
2284 /* If there is at least one more LWP, then the exit signal was
2285 not the end of the debugged application and should be
2286 ignored, unless GDB wants to hear about thread exits. */
2287 if (report_thread_events
2288 || last_thread_of_process_p (pid_of (thread
)))
2290 /* Since events are serialized to GDB core, and we can't
2291 report this one right now. Leave the status pending for
2292 the next time we're able to report it. */
2293 mark_lwp_dead (child
, wstat
);
2303 gdb_assert (WIFSTOPPED (wstat
));
2305 if (WIFSTOPPED (wstat
))
2307 struct process_info
*proc
;
2309 /* Architecture-specific setup after inferior is running. */
2310 proc
= find_process_pid (pid_of (thread
));
2311 if (proc
->tdesc
== NULL
)
2315 /* This needs to happen after we have attached to the
2316 inferior and it is stopped for the first time, but
2317 before we access any inferior registers. */
2318 linux_arch_setup_thread (thread
);
2322 /* The process is started, but GDBserver will do
2323 architecture-specific setup after the program stops at
2324 the first instruction. */
2325 child
->status_pending_p
= 1;
2326 child
->status_pending
= wstat
;
2332 if (WIFSTOPPED (wstat
) && child
->must_set_ptrace_flags
)
2334 struct process_info
*proc
= find_process_pid (pid_of (thread
));
2335 int options
= linux_low_ptrace_options (proc
->attached
);
2337 linux_enable_event_reporting (lwpid
, options
);
2338 child
->must_set_ptrace_flags
= 0;
2341 /* Be careful to not overwrite stop_pc until
2342 check_stopped_by_breakpoint is called. */
2343 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGTRAP
2344 && linux_is_extended_waitstatus (wstat
))
2346 child
->stop_pc
= get_pc (child
);
2347 if (handle_extended_wait (&child
, wstat
))
2349 /* The event has been handled, so just return without
2355 /* Check first whether this was a SW/HW breakpoint before checking
2356 watchpoints, because at least s390 can't tell the data address of
2357 hardware watchpoint hits, and returns stopped-by-watchpoint as
2358 long as there's a watchpoint set. */
2359 if (WIFSTOPPED (wstat
) && linux_wstatus_maybe_breakpoint (wstat
))
2361 if (check_stopped_by_breakpoint (child
))
2365 /* Note that TRAP_HWBKPT can indicate either a hardware breakpoint
2366 or hardware watchpoint. Check which is which if we got
2367 TARGET_STOPPED_BY_HW_BREAKPOINT. Likewise, we may have single
2368 stepped an instruction that triggered a watchpoint. In that
2369 case, on some architectures (such as x86), instead of
2370 TRAP_HWBKPT, si_code indicates TRAP_TRACE, and we need to check
2371 the debug registers separately. */
2372 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGTRAP
2373 && child
->stop_reason
!= TARGET_STOPPED_BY_SW_BREAKPOINT
)
2374 check_stopped_by_watchpoint (child
);
2377 child
->stop_pc
= get_pc (child
);
2379 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGSTOP
2380 && child
->stop_expected
)
2383 debug_printf ("Expected stop.\n");
2384 child
->stop_expected
= 0;
2386 if (thread
->last_resume_kind
== resume_stop
)
2388 /* We want to report the stop to the core. Treat the
2389 SIGSTOP as a normal event. */
2391 debug_printf ("LLW: resume_stop SIGSTOP caught for %s.\n",
2392 target_pid_to_str (ptid_of (thread
)));
2394 else if (stopping_threads
!= NOT_STOPPING_THREADS
)
2396 /* Stopping threads. We don't want this SIGSTOP to end up
2399 debug_printf ("LLW: SIGSTOP caught for %s "
2400 "while stopping threads.\n",
2401 target_pid_to_str (ptid_of (thread
)));
2406 /* This is a delayed SIGSTOP. Filter out the event. */
2408 debug_printf ("LLW: %s %s, 0, 0 (discard delayed SIGSTOP)\n",
2409 child
->stepping
? "step" : "continue",
2410 target_pid_to_str (ptid_of (thread
)));
2412 linux_resume_one_lwp (child
, child
->stepping
, 0, NULL
);
2417 child
->status_pending_p
= 1;
2418 child
->status_pending
= wstat
;
2422 /* Resume LWPs that are currently stopped without any pending status
2423 to report, but are resumed from the core's perspective. */
2426 resume_stopped_resumed_lwps (struct inferior_list_entry
*entry
)
2428 struct thread_info
*thread
= (struct thread_info
*) entry
;
2429 struct lwp_info
*lp
= get_thread_lwp (thread
);
2433 && !lp
->status_pending_p
2434 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
)
2436 int step
= thread
->last_resume_kind
== resume_step
;
2439 debug_printf ("RSRL: resuming stopped-resumed LWP %s at %s: step=%d\n",
2440 target_pid_to_str (ptid_of (thread
)),
2441 paddress (lp
->stop_pc
),
2444 linux_resume_one_lwp (lp
, step
, GDB_SIGNAL_0
, NULL
);
2448 /* Wait for an event from child(ren) WAIT_PTID, and return any that
2449 match FILTER_PTID (leaving others pending). The PTIDs can be:
2450 minus_one_ptid, to specify any child; a pid PTID, specifying all
2451 lwps of a thread group; or a PTID representing a single lwp. Store
2452 the stop status through the status pointer WSTAT. OPTIONS is
2453 passed to the waitpid call. Return 0 if no event was found and
2454 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
2455 was found. Return the PID of the stopped child otherwise. */
2458 linux_wait_for_event_filtered (ptid_t wait_ptid
, ptid_t filter_ptid
,
2459 int *wstatp
, int options
)
2461 struct thread_info
*event_thread
;
2462 struct lwp_info
*event_child
, *requested_child
;
2463 sigset_t block_mask
, prev_mask
;
2466 /* N.B. event_thread points to the thread_info struct that contains
2467 event_child. Keep them in sync. */
2468 event_thread
= NULL
;
2470 requested_child
= NULL
;
2472 /* Check for a lwp with a pending status. */
2474 if (ptid_equal (filter_ptid
, minus_one_ptid
) || ptid_is_pid (filter_ptid
))
2476 event_thread
= (struct thread_info
*)
2477 find_inferior (&all_threads
, status_pending_p_callback
, &filter_ptid
);
2478 if (event_thread
!= NULL
)
2479 event_child
= get_thread_lwp (event_thread
);
2480 if (debug_threads
&& event_thread
)
2481 debug_printf ("Got a pending child %ld\n", lwpid_of (event_thread
));
2483 else if (!ptid_equal (filter_ptid
, null_ptid
))
2485 requested_child
= find_lwp_pid (filter_ptid
);
2487 if (stopping_threads
== NOT_STOPPING_THREADS
2488 && requested_child
->status_pending_p
2489 && requested_child
->collecting_fast_tracepoint
)
2491 enqueue_one_deferred_signal (requested_child
,
2492 &requested_child
->status_pending
);
2493 requested_child
->status_pending_p
= 0;
2494 requested_child
->status_pending
= 0;
2495 linux_resume_one_lwp (requested_child
, 0, 0, NULL
);
2498 if (requested_child
->suspended
2499 && requested_child
->status_pending_p
)
2501 internal_error (__FILE__
, __LINE__
,
2502 "requesting an event out of a"
2503 " suspended child?");
2506 if (requested_child
->status_pending_p
)
2508 event_child
= requested_child
;
2509 event_thread
= get_lwp_thread (event_child
);
2513 if (event_child
!= NULL
)
2516 debug_printf ("Got an event from pending child %ld (%04x)\n",
2517 lwpid_of (event_thread
), event_child
->status_pending
);
2518 *wstatp
= event_child
->status_pending
;
2519 event_child
->status_pending_p
= 0;
2520 event_child
->status_pending
= 0;
2521 current_thread
= event_thread
;
2522 return lwpid_of (event_thread
);
2525 /* But if we don't find a pending event, we'll have to wait.
2527 We only enter this loop if no process has a pending wait status.
2528 Thus any action taken in response to a wait status inside this
2529 loop is responding as soon as we detect the status, not after any
2532 /* Make sure SIGCHLD is blocked until the sigsuspend below. Block
2533 all signals while here. */
2534 sigfillset (&block_mask
);
2535 sigprocmask (SIG_BLOCK
, &block_mask
, &prev_mask
);
2537 /* Always pull all events out of the kernel. We'll randomly select
2538 an event LWP out of all that have events, to prevent
2540 while (event_child
== NULL
)
2544 /* Always use -1 and WNOHANG, due to couple of a kernel/ptrace
2547 - If the thread group leader exits while other threads in the
2548 thread group still exist, waitpid(TGID, ...) hangs. That
2549 waitpid won't return an exit status until the other threads
2550 in the group are reaped.
2552 - When a non-leader thread execs, that thread just vanishes
2553 without reporting an exit (so we'd hang if we waited for it
2554 explicitly in that case). The exec event is reported to
2557 ret
= my_waitpid (-1, wstatp
, options
| WNOHANG
);
2560 debug_printf ("LWFE: waitpid(-1, ...) returned %d, %s\n",
2561 ret
, errno
? strerror (errno
) : "ERRNO-OK");
2567 debug_printf ("LLW: waitpid %ld received %s\n",
2568 (long) ret
, status_to_str (*wstatp
));
2571 /* Filter all events. IOW, leave all events pending. We'll
2572 randomly select an event LWP out of all that have events
2574 linux_low_filter_event (ret
, *wstatp
);
2575 /* Retry until nothing comes out of waitpid. A single
2576 SIGCHLD can indicate more than one child stopped. */
2580 /* Now that we've pulled all events out of the kernel, resume
2581 LWPs that don't have an interesting event to report. */
2582 if (stopping_threads
== NOT_STOPPING_THREADS
)
2583 for_each_inferior (&all_threads
, resume_stopped_resumed_lwps
);
2585 /* ... and find an LWP with a status to report to the core, if
2587 event_thread
= (struct thread_info
*)
2588 find_inferior (&all_threads
, status_pending_p_callback
, &filter_ptid
);
2589 if (event_thread
!= NULL
)
2591 event_child
= get_thread_lwp (event_thread
);
2592 *wstatp
= event_child
->status_pending
;
2593 event_child
->status_pending_p
= 0;
2594 event_child
->status_pending
= 0;
2598 /* Check for zombie thread group leaders. Those can't be reaped
2599 until all other threads in the thread group are. */
2600 check_zombie_leaders ();
2602 /* If there are no resumed children left in the set of LWPs we
2603 want to wait for, bail. We can't just block in
2604 waitpid/sigsuspend, because lwps might have been left stopped
2605 in trace-stop state, and we'd be stuck forever waiting for
2606 their status to change (which would only happen if we resumed
2607 them). Even if WNOHANG is set, this return code is preferred
2608 over 0 (below), as it is more detailed. */
2609 if ((find_inferior (&all_threads
,
2610 not_stopped_callback
,
2611 &wait_ptid
) == NULL
))
2614 debug_printf ("LLW: exit (no unwaited-for LWP)\n");
2615 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2619 /* No interesting event to report to the caller. */
2620 if ((options
& WNOHANG
))
2623 debug_printf ("WNOHANG set, no event found\n");
2625 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2629 /* Block until we get an event reported with SIGCHLD. */
2631 debug_printf ("sigsuspend'ing\n");
2633 sigsuspend (&prev_mask
);
2634 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2638 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2640 current_thread
= event_thread
;
2642 return lwpid_of (event_thread
);
2645 /* Wait for an event from child(ren) PTID. PTIDs can be:
2646 minus_one_ptid, to specify any child; a pid PTID, specifying all
2647 lwps of a thread group; or a PTID representing a single lwp. Store
2648 the stop status through the status pointer WSTAT. OPTIONS is
2649 passed to the waitpid call. Return 0 if no event was found and
2650 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
2651 was found. Return the PID of the stopped child otherwise. */
2654 linux_wait_for_event (ptid_t ptid
, int *wstatp
, int options
)
2656 return linux_wait_for_event_filtered (ptid
, ptid
, wstatp
, options
);
2659 /* Count the LWP's that have had events. */
2662 count_events_callback (struct inferior_list_entry
*entry
, void *data
)
2664 struct thread_info
*thread
= (struct thread_info
*) entry
;
2665 struct lwp_info
*lp
= get_thread_lwp (thread
);
2666 int *count
= (int *) data
;
2668 gdb_assert (count
!= NULL
);
2670 /* Count only resumed LWPs that have an event pending. */
2671 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2672 && lp
->status_pending_p
)
2678 /* Select the LWP (if any) that is currently being single-stepped. */
2681 select_singlestep_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
2683 struct thread_info
*thread
= (struct thread_info
*) entry
;
2684 struct lwp_info
*lp
= get_thread_lwp (thread
);
2686 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2687 && thread
->last_resume_kind
== resume_step
2688 && lp
->status_pending_p
)
2694 /* Select the Nth LWP that has had an event. */
2697 select_event_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
2699 struct thread_info
*thread
= (struct thread_info
*) entry
;
2700 struct lwp_info
*lp
= get_thread_lwp (thread
);
2701 int *selector
= (int *) data
;
2703 gdb_assert (selector
!= NULL
);
2705 /* Select only resumed LWPs that have an event pending. */
2706 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2707 && lp
->status_pending_p
)
2708 if ((*selector
)-- == 0)
2714 /* Select one LWP out of those that have events pending. */
2717 select_event_lwp (struct lwp_info
**orig_lp
)
2720 int random_selector
;
2721 struct thread_info
*event_thread
= NULL
;
2723 /* In all-stop, give preference to the LWP that is being
2724 single-stepped. There will be at most one, and it's the LWP that
2725 the core is most interested in. If we didn't do this, then we'd
2726 have to handle pending step SIGTRAPs somehow in case the core
2727 later continues the previously-stepped thread, otherwise we'd
2728 report the pending SIGTRAP, and the core, not having stepped the
2729 thread, wouldn't understand what the trap was for, and therefore
2730 would report it to the user as a random signal. */
2734 = (struct thread_info
*) find_inferior (&all_threads
,
2735 select_singlestep_lwp_callback
,
2737 if (event_thread
!= NULL
)
2740 debug_printf ("SEL: Select single-step %s\n",
2741 target_pid_to_str (ptid_of (event_thread
)));
2744 if (event_thread
== NULL
)
2746 /* No single-stepping LWP. Select one at random, out of those
2747 which have had events. */
2749 /* First see how many events we have. */
2750 find_inferior (&all_threads
, count_events_callback
, &num_events
);
2751 gdb_assert (num_events
> 0);
2753 /* Now randomly pick a LWP out of those that have had
2755 random_selector
= (int)
2756 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
2758 if (debug_threads
&& num_events
> 1)
2759 debug_printf ("SEL: Found %d SIGTRAP events, selecting #%d\n",
2760 num_events
, random_selector
);
2763 = (struct thread_info
*) find_inferior (&all_threads
,
2764 select_event_lwp_callback
,
2768 if (event_thread
!= NULL
)
2770 struct lwp_info
*event_lp
= get_thread_lwp (event_thread
);
2772 /* Switch the event LWP. */
2773 *orig_lp
= event_lp
;
2777 /* Decrement the suspend count of an LWP. */
2780 unsuspend_one_lwp (struct inferior_list_entry
*entry
, void *except
)
2782 struct thread_info
*thread
= (struct thread_info
*) entry
;
2783 struct lwp_info
*lwp
= get_thread_lwp (thread
);
2785 /* Ignore EXCEPT. */
2789 lwp_suspended_decr (lwp
);
2793 /* Decrement the suspend count of all LWPs, except EXCEPT, if non
2797 unsuspend_all_lwps (struct lwp_info
*except
)
2799 find_inferior (&all_threads
, unsuspend_one_lwp
, except
);
2802 static void move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
);
2803 static int stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
,
2805 static int lwp_running (struct inferior_list_entry
*entry
, void *data
);
2806 static ptid_t
linux_wait_1 (ptid_t ptid
,
2807 struct target_waitstatus
*ourstatus
,
2808 int target_options
);
2810 /* Stabilize threads (move out of jump pads).
2812 If a thread is midway collecting a fast tracepoint, we need to
2813 finish the collection and move it out of the jump pad before
2814 reporting the signal.
2816 This avoids recursion while collecting (when a signal arrives
2817 midway, and the signal handler itself collects), which would trash
2818 the trace buffer. In case the user set a breakpoint in a signal
2819 handler, this avoids the backtrace showing the jump pad, etc..
2820 Most importantly, there are certain things we can't do safely if
2821 threads are stopped in a jump pad (or in its callee's). For
2824 - starting a new trace run. A thread still collecting the
2825 previous run, could trash the trace buffer when resumed. The trace
2826 buffer control structures would have been reset but the thread had
2827 no way to tell. The thread could even midway memcpy'ing to the
2828 buffer, which would mean that when resumed, it would clobber the
2829 trace buffer that had been set for a new run.
2831 - we can't rewrite/reuse the jump pads for new tracepoints
2832 safely. Say you do tstart while a thread is stopped midway while
2833 collecting. When the thread is later resumed, it finishes the
2834 collection, and returns to the jump pad, to execute the original
2835 instruction that was under the tracepoint jump at the time the
2836 older run had been started. If the jump pad had been rewritten
2837 since for something else in the new run, the thread would now
2838 execute the wrong / random instructions. */
2841 linux_stabilize_threads (void)
2843 struct thread_info
*saved_thread
;
2844 struct thread_info
*thread_stuck
;
2847 = (struct thread_info
*) find_inferior (&all_threads
,
2848 stuck_in_jump_pad_callback
,
2850 if (thread_stuck
!= NULL
)
2853 debug_printf ("can't stabilize, LWP %ld is stuck in jump pad\n",
2854 lwpid_of (thread_stuck
));
2858 saved_thread
= current_thread
;
2860 stabilizing_threads
= 1;
2863 for_each_inferior (&all_threads
, move_out_of_jump_pad_callback
);
2865 /* Loop until all are stopped out of the jump pads. */
2866 while (find_inferior (&all_threads
, lwp_running
, NULL
) != NULL
)
2868 struct target_waitstatus ourstatus
;
2869 struct lwp_info
*lwp
;
2872 /* Note that we go through the full wait even loop. While
2873 moving threads out of jump pad, we need to be able to step
2874 over internal breakpoints and such. */
2875 linux_wait_1 (minus_one_ptid
, &ourstatus
, 0);
2877 if (ourstatus
.kind
== TARGET_WAITKIND_STOPPED
)
2879 lwp
= get_thread_lwp (current_thread
);
2882 lwp_suspended_inc (lwp
);
2884 if (ourstatus
.value
.sig
!= GDB_SIGNAL_0
2885 || current_thread
->last_resume_kind
== resume_stop
)
2887 wstat
= W_STOPCODE (gdb_signal_to_host (ourstatus
.value
.sig
));
2888 enqueue_one_deferred_signal (lwp
, &wstat
);
2893 find_inferior (&all_threads
, unsuspend_one_lwp
, NULL
);
2895 stabilizing_threads
= 0;
2897 current_thread
= saved_thread
;
2902 = (struct thread_info
*) find_inferior (&all_threads
,
2903 stuck_in_jump_pad_callback
,
2905 if (thread_stuck
!= NULL
)
2906 debug_printf ("couldn't stabilize, LWP %ld got stuck in jump pad\n",
2907 lwpid_of (thread_stuck
));
2911 /* Convenience function that is called when the kernel reports an
2912 event that is not passed out to GDB. */
2915 ignore_event (struct target_waitstatus
*ourstatus
)
2917 /* If we got an event, there may still be others, as a single
2918 SIGCHLD can indicate more than one child stopped. This forces
2919 another target_wait call. */
2922 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2926 /* Convenience function that is called when the kernel reports an exit
2927 event. This decides whether to report the event to GDB as a
2928 process exit event, a thread exit event, or to suppress the
2932 filter_exit_event (struct lwp_info
*event_child
,
2933 struct target_waitstatus
*ourstatus
)
2935 struct thread_info
*thread
= get_lwp_thread (event_child
);
2936 ptid_t ptid
= ptid_of (thread
);
2938 if (!last_thread_of_process_p (pid_of (thread
)))
2940 if (report_thread_events
)
2941 ourstatus
->kind
= TARGET_WAITKIND_THREAD_EXITED
;
2943 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2945 delete_lwp (event_child
);
2950 /* Wait for process, returns status. */
2953 linux_wait_1 (ptid_t ptid
,
2954 struct target_waitstatus
*ourstatus
, int target_options
)
2957 struct lwp_info
*event_child
;
2960 int step_over_finished
;
2961 int bp_explains_trap
;
2962 int maybe_internal_trap
;
2971 debug_printf ("linux_wait_1: [%s]\n", target_pid_to_str (ptid
));
2974 /* Translate generic target options into linux options. */
2976 if (target_options
& TARGET_WNOHANG
)
2979 bp_explains_trap
= 0;
2982 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2984 /* Find a resumed LWP, if any. */
2985 if (find_inferior (&all_threads
,
2986 status_pending_p_callback
,
2987 &minus_one_ptid
) != NULL
)
2989 else if ((find_inferior (&all_threads
,
2990 not_stopped_callback
,
2991 &minus_one_ptid
) != NULL
))
2996 if (ptid_equal (step_over_bkpt
, null_ptid
))
2997 pid
= linux_wait_for_event (ptid
, &w
, options
);
3001 debug_printf ("step_over_bkpt set [%s], doing a blocking wait\n",
3002 target_pid_to_str (step_over_bkpt
));
3003 pid
= linux_wait_for_event (step_over_bkpt
, &w
, options
& ~WNOHANG
);
3006 if (pid
== 0 || (pid
== -1 && !any_resumed
))
3008 gdb_assert (target_options
& TARGET_WNOHANG
);
3012 debug_printf ("linux_wait_1 ret = null_ptid, "
3013 "TARGET_WAITKIND_IGNORE\n");
3017 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3024 debug_printf ("linux_wait_1 ret = null_ptid, "
3025 "TARGET_WAITKIND_NO_RESUMED\n");
3029 ourstatus
->kind
= TARGET_WAITKIND_NO_RESUMED
;
3033 event_child
= get_thread_lwp (current_thread
);
3035 /* linux_wait_for_event only returns an exit status for the last
3036 child of a process. Report it. */
3037 if (WIFEXITED (w
) || WIFSIGNALED (w
))
3041 ourstatus
->kind
= TARGET_WAITKIND_EXITED
;
3042 ourstatus
->value
.integer
= WEXITSTATUS (w
);
3046 debug_printf ("linux_wait_1 ret = %s, exited with "
3048 target_pid_to_str (ptid_of (current_thread
)),
3055 ourstatus
->kind
= TARGET_WAITKIND_SIGNALLED
;
3056 ourstatus
->value
.sig
= gdb_signal_from_host (WTERMSIG (w
));
3060 debug_printf ("linux_wait_1 ret = %s, terminated with "
3062 target_pid_to_str (ptid_of (current_thread
)),
3068 if (ourstatus
->kind
== TARGET_WAITKIND_EXITED
)
3069 return filter_exit_event (event_child
, ourstatus
);
3071 return ptid_of (current_thread
);
3074 /* If step-over executes a breakpoint instruction, it means a
3075 gdb/gdbserver breakpoint had been planted on top of a permanent
3076 breakpoint. The PC has been adjusted by
3077 check_stopped_by_breakpoint to point at the breakpoint address.
3078 Advance the PC manually past the breakpoint, otherwise the
3079 program would keep trapping the permanent breakpoint forever. */
3080 if (!ptid_equal (step_over_bkpt
, null_ptid
)
3081 && event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
)
3083 int increment_pc
= 0;
3084 int breakpoint_kind
= 0;
3085 CORE_ADDR stop_pc
= event_child
->stop_pc
;
3088 the_target
->breakpoint_kind_from_current_state (&stop_pc
);
3089 the_target
->sw_breakpoint_from_kind (breakpoint_kind
, &increment_pc
);
3093 debug_printf ("step-over for %s executed software breakpoint\n",
3094 target_pid_to_str (ptid_of (current_thread
)));
3097 if (increment_pc
!= 0)
3099 struct regcache
*regcache
3100 = get_thread_regcache (current_thread
, 1);
3102 event_child
->stop_pc
+= increment_pc
;
3103 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
3105 if (!(*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))
3106 event_child
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3110 /* If this event was not handled before, and is not a SIGTRAP, we
3111 report it. SIGILL and SIGSEGV are also treated as traps in case
3112 a breakpoint is inserted at the current PC. If this target does
3113 not support internal breakpoints at all, we also report the
3114 SIGTRAP without further processing; it's of no concern to us. */
3116 = (supports_breakpoints ()
3117 && (WSTOPSIG (w
) == SIGTRAP
3118 || ((WSTOPSIG (w
) == SIGILL
3119 || WSTOPSIG (w
) == SIGSEGV
)
3120 && (*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))));
3122 if (maybe_internal_trap
)
3124 /* Handle anything that requires bookkeeping before deciding to
3125 report the event or continue waiting. */
3127 /* First check if we can explain the SIGTRAP with an internal
3128 breakpoint, or if we should possibly report the event to GDB.
3129 Do this before anything that may remove or insert a
3131 bp_explains_trap
= breakpoint_inserted_here (event_child
->stop_pc
);
3133 /* We have a SIGTRAP, possibly a step-over dance has just
3134 finished. If so, tweak the state machine accordingly,
3135 reinsert breakpoints and delete any reinsert (software
3136 single-step) breakpoints. */
3137 step_over_finished
= finish_step_over (event_child
);
3139 /* Now invoke the callbacks of any internal breakpoints there. */
3140 check_breakpoints (event_child
->stop_pc
);
3142 /* Handle tracepoint data collecting. This may overflow the
3143 trace buffer, and cause a tracing stop, removing
3145 trace_event
= handle_tracepoints (event_child
);
3147 if (bp_explains_trap
)
3149 /* If we stepped or ran into an internal breakpoint, we've
3150 already handled it. So next time we resume (from this
3151 PC), we should step over it. */
3153 debug_printf ("Hit a gdbserver breakpoint.\n");
3155 if (breakpoint_here (event_child
->stop_pc
))
3156 event_child
->need_step_over
= 1;
3161 /* We have some other signal, possibly a step-over dance was in
3162 progress, and it should be cancelled too. */
3163 step_over_finished
= finish_step_over (event_child
);
3166 /* We have all the data we need. Either report the event to GDB, or
3167 resume threads and keep waiting for more. */
3169 /* If we're collecting a fast tracepoint, finish the collection and
3170 move out of the jump pad before delivering a signal. See
3171 linux_stabilize_threads. */
3174 && WSTOPSIG (w
) != SIGTRAP
3175 && supports_fast_tracepoints ()
3176 && agent_loaded_p ())
3179 debug_printf ("Got signal %d for LWP %ld. Check if we need "
3180 "to defer or adjust it.\n",
3181 WSTOPSIG (w
), lwpid_of (current_thread
));
3183 /* Allow debugging the jump pad itself. */
3184 if (current_thread
->last_resume_kind
!= resume_step
3185 && maybe_move_out_of_jump_pad (event_child
, &w
))
3187 enqueue_one_deferred_signal (event_child
, &w
);
3190 debug_printf ("Signal %d for LWP %ld deferred (in jump pad)\n",
3191 WSTOPSIG (w
), lwpid_of (current_thread
));
3193 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
3195 return ignore_event (ourstatus
);
3199 if (event_child
->collecting_fast_tracepoint
)
3202 debug_printf ("LWP %ld was trying to move out of the jump pad (%d). "
3203 "Check if we're already there.\n",
3204 lwpid_of (current_thread
),
3205 event_child
->collecting_fast_tracepoint
);
3209 event_child
->collecting_fast_tracepoint
3210 = linux_fast_tracepoint_collecting (event_child
, NULL
);
3212 if (event_child
->collecting_fast_tracepoint
!= 1)
3214 /* No longer need this breakpoint. */
3215 if (event_child
->exit_jump_pad_bkpt
!= NULL
)
3218 debug_printf ("No longer need exit-jump-pad bkpt; removing it."
3219 "stopping all threads momentarily.\n");
3221 /* Other running threads could hit this breakpoint.
3222 We don't handle moribund locations like GDB does,
3223 instead we always pause all threads when removing
3224 breakpoints, so that any step-over or
3225 decr_pc_after_break adjustment is always taken
3226 care of while the breakpoint is still
3228 stop_all_lwps (1, event_child
);
3230 delete_breakpoint (event_child
->exit_jump_pad_bkpt
);
3231 event_child
->exit_jump_pad_bkpt
= NULL
;
3233 unstop_all_lwps (1, event_child
);
3235 gdb_assert (event_child
->suspended
>= 0);
3239 if (event_child
->collecting_fast_tracepoint
== 0)
3242 debug_printf ("fast tracepoint finished "
3243 "collecting successfully.\n");
3245 /* We may have a deferred signal to report. */
3246 if (dequeue_one_deferred_signal (event_child
, &w
))
3249 debug_printf ("dequeued one signal.\n");
3254 debug_printf ("no deferred signals.\n");
3256 if (stabilizing_threads
)
3258 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
3259 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
3263 debug_printf ("linux_wait_1 ret = %s, stopped "
3264 "while stabilizing threads\n",
3265 target_pid_to_str (ptid_of (current_thread
)));
3269 return ptid_of (current_thread
);
3275 /* Check whether GDB would be interested in this event. */
3277 /* If GDB is not interested in this signal, don't stop other
3278 threads, and don't report it to GDB. Just resume the inferior
3279 right away. We do this for threading-related signals as well as
3280 any that GDB specifically requested we ignore. But never ignore
3281 SIGSTOP if we sent it ourselves, and do not ignore signals when
3282 stepping - they may require special handling to skip the signal
3283 handler. Also never ignore signals that could be caused by a
3285 /* FIXME drow/2002-06-09: Get signal numbers from the inferior's
3288 && current_thread
->last_resume_kind
!= resume_step
3290 #if defined (USE_THREAD_DB) && !defined (__ANDROID__)
3291 (current_process ()->priv
->thread_db
!= NULL
3292 && (WSTOPSIG (w
) == __SIGRTMIN
3293 || WSTOPSIG (w
) == __SIGRTMIN
+ 1))
3296 (pass_signals
[gdb_signal_from_host (WSTOPSIG (w
))]
3297 && !(WSTOPSIG (w
) == SIGSTOP
3298 && current_thread
->last_resume_kind
== resume_stop
)
3299 && !linux_wstatus_maybe_breakpoint (w
))))
3301 siginfo_t info
, *info_p
;
3304 debug_printf ("Ignored signal %d for LWP %ld.\n",
3305 WSTOPSIG (w
), lwpid_of (current_thread
));
3307 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
3308 (PTRACE_TYPE_ARG3
) 0, &info
) == 0)
3313 if (step_over_finished
)
3315 /* We cancelled this thread's step-over above. We still
3316 need to unsuspend all other LWPs, and set them back
3317 running again while the signal handler runs. */
3318 unsuspend_all_lwps (event_child
);
3320 /* Enqueue the pending signal info so that proceed_all_lwps
3322 enqueue_pending_signal (event_child
, WSTOPSIG (w
), info_p
);
3324 proceed_all_lwps ();
3328 linux_resume_one_lwp (event_child
, event_child
->stepping
,
3329 WSTOPSIG (w
), info_p
);
3331 return ignore_event (ourstatus
);
3334 /* Note that all addresses are always "out of the step range" when
3335 there's no range to begin with. */
3336 in_step_range
= lwp_in_step_range (event_child
);
3338 /* If GDB wanted this thread to single step, and the thread is out
3339 of the step range, we always want to report the SIGTRAP, and let
3340 GDB handle it. Watchpoints should always be reported. So should
3341 signals we can't explain. A SIGTRAP we can't explain could be a
3342 GDB breakpoint --- we may or not support Z0 breakpoints. If we
3343 do, we're be able to handle GDB breakpoints on top of internal
3344 breakpoints, by handling the internal breakpoint and still
3345 reporting the event to GDB. If we don't, we're out of luck, GDB
3346 won't see the breakpoint hit. If we see a single-step event but
3347 the thread should be continuing, don't pass the trap to gdb.
3348 That indicates that we had previously finished a single-step but
3349 left the single-step pending -- see
3350 complete_ongoing_step_over. */
3351 report_to_gdb
= (!maybe_internal_trap
3352 || (current_thread
->last_resume_kind
== resume_step
3354 || event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
3356 && !bp_explains_trap
3358 && !step_over_finished
3359 && !(current_thread
->last_resume_kind
== resume_continue
3360 && event_child
->stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
))
3361 || (gdb_breakpoint_here (event_child
->stop_pc
)
3362 && gdb_condition_true_at_breakpoint (event_child
->stop_pc
)
3363 && gdb_no_commands_at_breakpoint (event_child
->stop_pc
))
3364 || event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
);
3366 run_breakpoint_commands (event_child
->stop_pc
);
3368 /* We found no reason GDB would want us to stop. We either hit one
3369 of our own breakpoints, or finished an internal step GDB
3370 shouldn't know about. */
3375 if (bp_explains_trap
)
3376 debug_printf ("Hit a gdbserver breakpoint.\n");
3377 if (step_over_finished
)
3378 debug_printf ("Step-over finished.\n");
3380 debug_printf ("Tracepoint event.\n");
3381 if (lwp_in_step_range (event_child
))
3382 debug_printf ("Range stepping pc 0x%s [0x%s, 0x%s).\n",
3383 paddress (event_child
->stop_pc
),
3384 paddress (event_child
->step_range_start
),
3385 paddress (event_child
->step_range_end
));
3388 /* We're not reporting this breakpoint to GDB, so apply the
3389 decr_pc_after_break adjustment to the inferior's regcache
3392 if (the_low_target
.set_pc
!= NULL
)
3394 struct regcache
*regcache
3395 = get_thread_regcache (current_thread
, 1);
3396 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
3399 /* We may have finished stepping over a breakpoint. If so,
3400 we've stopped and suspended all LWPs momentarily except the
3401 stepping one. This is where we resume them all again. We're
3402 going to keep waiting, so use proceed, which handles stepping
3403 over the next breakpoint. */
3405 debug_printf ("proceeding all threads.\n");
3407 if (step_over_finished
)
3408 unsuspend_all_lwps (event_child
);
3410 proceed_all_lwps ();
3411 return ignore_event (ourstatus
);
3416 if (event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
3420 str
= target_waitstatus_to_string (&event_child
->waitstatus
);
3421 debug_printf ("LWP %ld: extended event with waitstatus %s\n",
3422 lwpid_of (get_lwp_thread (event_child
)), str
);
3425 if (current_thread
->last_resume_kind
== resume_step
)
3427 if (event_child
->step_range_start
== event_child
->step_range_end
)
3428 debug_printf ("GDB wanted to single-step, reporting event.\n");
3429 else if (!lwp_in_step_range (event_child
))
3430 debug_printf ("Out of step range, reporting event.\n");
3432 if (event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
)
3433 debug_printf ("Stopped by watchpoint.\n");
3434 else if (gdb_breakpoint_here (event_child
->stop_pc
))
3435 debug_printf ("Stopped by GDB breakpoint.\n");
3437 debug_printf ("Hit a non-gdbserver trap event.\n");
3440 /* Alright, we're going to report a stop. */
3442 if (!stabilizing_threads
)
3444 /* In all-stop, stop all threads. */
3446 stop_all_lwps (0, NULL
);
3448 /* If we're not waiting for a specific LWP, choose an event LWP
3449 from among those that have had events. Giving equal priority
3450 to all LWPs that have had events helps prevent
3452 if (ptid_equal (ptid
, minus_one_ptid
))
3454 event_child
->status_pending_p
= 1;
3455 event_child
->status_pending
= w
;
3457 select_event_lwp (&event_child
);
3459 /* current_thread and event_child must stay in sync. */
3460 current_thread
= get_lwp_thread (event_child
);
3462 event_child
->status_pending_p
= 0;
3463 w
= event_child
->status_pending
;
3466 if (step_over_finished
)
3470 /* If we were doing a step-over, all other threads but
3471 the stepping one had been paused in start_step_over,
3472 with their suspend counts incremented. We don't want
3473 to do a full unstop/unpause, because we're in
3474 all-stop mode (so we want threads stopped), but we
3475 still need to unsuspend the other threads, to
3476 decrement their `suspended' count back. */
3477 unsuspend_all_lwps (event_child
);
3481 /* If we just finished a step-over, then all threads had
3482 been momentarily paused. In all-stop, that's fine,
3483 we want threads stopped by now anyway. In non-stop,
3484 we need to re-resume threads that GDB wanted to be
3486 unstop_all_lwps (1, event_child
);
3490 /* Stabilize threads (move out of jump pads). */
3492 stabilize_threads ();
3496 /* If we just finished a step-over, then all threads had been
3497 momentarily paused. In all-stop, that's fine, we want
3498 threads stopped by now anyway. In non-stop, we need to
3499 re-resume threads that GDB wanted to be running. */
3500 if (step_over_finished
)
3501 unstop_all_lwps (1, event_child
);
3504 if (event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
3506 /* If the reported event is an exit, fork, vfork or exec, let
3508 *ourstatus
= event_child
->waitstatus
;
3509 /* Clear the event lwp's waitstatus since we handled it already. */
3510 event_child
->waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
3513 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
3515 /* Now that we've selected our final event LWP, un-adjust its PC if
3516 it was a software breakpoint, and the client doesn't know we can
3517 adjust the breakpoint ourselves. */
3518 if (event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3519 && !swbreak_feature
)
3521 int decr_pc
= the_low_target
.decr_pc_after_break
;
3525 struct regcache
*regcache
3526 = get_thread_regcache (current_thread
, 1);
3527 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
+ decr_pc
);
3531 if (current_thread
->last_resume_kind
== resume_stop
3532 && WSTOPSIG (w
) == SIGSTOP
)
3534 /* A thread that has been requested to stop by GDB with vCont;t,
3535 and it stopped cleanly, so report as SIG0. The use of
3536 SIGSTOP is an implementation detail. */
3537 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
3539 else if (current_thread
->last_resume_kind
== resume_stop
3540 && WSTOPSIG (w
) != SIGSTOP
)
3542 /* A thread that has been requested to stop by GDB with vCont;t,
3543 but, it stopped for other reasons. */
3544 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
3546 else if (ourstatus
->kind
== TARGET_WAITKIND_STOPPED
)
3548 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
3551 gdb_assert (ptid_equal (step_over_bkpt
, null_ptid
));
3555 debug_printf ("linux_wait_1 ret = %s, %d, %d\n",
3556 target_pid_to_str (ptid_of (current_thread
)),
3557 ourstatus
->kind
, ourstatus
->value
.sig
);
3561 if (ourstatus
->kind
== TARGET_WAITKIND_EXITED
)
3562 return filter_exit_event (event_child
, ourstatus
);
3564 return ptid_of (current_thread
);
3567 /* Get rid of any pending event in the pipe. */
3569 async_file_flush (void)
3575 ret
= read (linux_event_pipe
[0], &buf
, 1);
3576 while (ret
>= 0 || (ret
== -1 && errno
== EINTR
));
3579 /* Put something in the pipe, so the event loop wakes up. */
3581 async_file_mark (void)
3585 async_file_flush ();
3588 ret
= write (linux_event_pipe
[1], "+", 1);
3589 while (ret
== 0 || (ret
== -1 && errno
== EINTR
));
3591 /* Ignore EAGAIN. If the pipe is full, the event loop will already
3592 be awakened anyway. */
3596 linux_wait (ptid_t ptid
,
3597 struct target_waitstatus
*ourstatus
, int target_options
)
3601 /* Flush the async file first. */
3602 if (target_is_async_p ())
3603 async_file_flush ();
3607 event_ptid
= linux_wait_1 (ptid
, ourstatus
, target_options
);
3609 while ((target_options
& TARGET_WNOHANG
) == 0
3610 && ptid_equal (event_ptid
, null_ptid
)
3611 && ourstatus
->kind
== TARGET_WAITKIND_IGNORE
);
3613 /* If at least one stop was reported, there may be more. A single
3614 SIGCHLD can signal more than one child stop. */
3615 if (target_is_async_p ()
3616 && (target_options
& TARGET_WNOHANG
) != 0
3617 && !ptid_equal (event_ptid
, null_ptid
))
3623 /* Send a signal to an LWP. */
3626 kill_lwp (unsigned long lwpid
, int signo
)
3628 /* Use tkill, if possible, in case we are using nptl threads. If tkill
3629 fails, then we are not using nptl threads and we should be using kill. */
3633 static int tkill_failed
;
3640 ret
= syscall (__NR_tkill
, lwpid
, signo
);
3641 if (errno
!= ENOSYS
)
3648 return kill (lwpid
, signo
);
3652 linux_stop_lwp (struct lwp_info
*lwp
)
3658 send_sigstop (struct lwp_info
*lwp
)
3662 pid
= lwpid_of (get_lwp_thread (lwp
));
3664 /* If we already have a pending stop signal for this process, don't
3666 if (lwp
->stop_expected
)
3669 debug_printf ("Have pending sigstop for lwp %d\n", pid
);
3675 debug_printf ("Sending sigstop to lwp %d\n", pid
);
3677 lwp
->stop_expected
= 1;
3678 kill_lwp (pid
, SIGSTOP
);
3682 send_sigstop_callback (struct inferior_list_entry
*entry
, void *except
)
3684 struct thread_info
*thread
= (struct thread_info
*) entry
;
3685 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3687 /* Ignore EXCEPT. */
3698 /* Increment the suspend count of an LWP, and stop it, if not stopped
3701 suspend_and_send_sigstop_callback (struct inferior_list_entry
*entry
,
3704 struct thread_info
*thread
= (struct thread_info
*) entry
;
3705 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3707 /* Ignore EXCEPT. */
3711 lwp_suspended_inc (lwp
);
3713 return send_sigstop_callback (entry
, except
);
3717 mark_lwp_dead (struct lwp_info
*lwp
, int wstat
)
3719 /* Store the exit status for later. */
3720 lwp
->status_pending_p
= 1;
3721 lwp
->status_pending
= wstat
;
3723 /* Store in waitstatus as well, as there's nothing else to process
3725 if (WIFEXITED (wstat
))
3727 lwp
->waitstatus
.kind
= TARGET_WAITKIND_EXITED
;
3728 lwp
->waitstatus
.value
.integer
= WEXITSTATUS (wstat
);
3730 else if (WIFSIGNALED (wstat
))
3732 lwp
->waitstatus
.kind
= TARGET_WAITKIND_SIGNALLED
;
3733 lwp
->waitstatus
.value
.sig
= gdb_signal_from_host (WTERMSIG (wstat
));
3736 /* Prevent trying to stop it. */
3739 /* No further stops are expected from a dead lwp. */
3740 lwp
->stop_expected
= 0;
3743 /* Return true if LWP has exited already, and has a pending exit event
3744 to report to GDB. */
3747 lwp_is_marked_dead (struct lwp_info
*lwp
)
3749 return (lwp
->status_pending_p
3750 && (WIFEXITED (lwp
->status_pending
)
3751 || WIFSIGNALED (lwp
->status_pending
)));
3754 /* Wait for all children to stop for the SIGSTOPs we just queued. */
3757 wait_for_sigstop (void)
3759 struct thread_info
*saved_thread
;
3764 saved_thread
= current_thread
;
3765 if (saved_thread
!= NULL
)
3766 saved_tid
= saved_thread
->entry
.id
;
3768 saved_tid
= null_ptid
; /* avoid bogus unused warning */
3771 debug_printf ("wait_for_sigstop: pulling events\n");
3773 /* Passing NULL_PTID as filter indicates we want all events to be
3774 left pending. Eventually this returns when there are no
3775 unwaited-for children left. */
3776 ret
= linux_wait_for_event_filtered (minus_one_ptid
, null_ptid
,
3778 gdb_assert (ret
== -1);
3780 if (saved_thread
== NULL
|| linux_thread_alive (saved_tid
))
3781 current_thread
= saved_thread
;
3785 debug_printf ("Previously current thread died.\n");
3787 /* We can't change the current inferior behind GDB's back,
3788 otherwise, a subsequent command may apply to the wrong
3790 current_thread
= NULL
;
3794 /* Returns true if LWP ENTRY is stopped in a jump pad, and we can't
3795 move it out, because we need to report the stop event to GDB. For
3796 example, if the user puts a breakpoint in the jump pad, it's
3797 because she wants to debug it. */
3800 stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
, void *data
)
3802 struct thread_info
*thread
= (struct thread_info
*) entry
;
3803 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3805 if (lwp
->suspended
!= 0)
3807 internal_error (__FILE__
, __LINE__
,
3808 "LWP %ld is suspended, suspended=%d\n",
3809 lwpid_of (thread
), lwp
->suspended
);
3811 gdb_assert (lwp
->stopped
);
3813 /* Allow debugging the jump pad, gdb_collect, etc.. */
3814 return (supports_fast_tracepoints ()
3815 && agent_loaded_p ()
3816 && (gdb_breakpoint_here (lwp
->stop_pc
)
3817 || lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
3818 || thread
->last_resume_kind
== resume_step
)
3819 && linux_fast_tracepoint_collecting (lwp
, NULL
));
3823 move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
)
3825 struct thread_info
*thread
= (struct thread_info
*) entry
;
3826 struct thread_info
*saved_thread
;
3827 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3830 if (lwp
->suspended
!= 0)
3832 internal_error (__FILE__
, __LINE__
,
3833 "LWP %ld is suspended, suspended=%d\n",
3834 lwpid_of (thread
), lwp
->suspended
);
3836 gdb_assert (lwp
->stopped
);
3838 /* For gdb_breakpoint_here. */
3839 saved_thread
= current_thread
;
3840 current_thread
= thread
;
3842 wstat
= lwp
->status_pending_p
? &lwp
->status_pending
: NULL
;
3844 /* Allow debugging the jump pad, gdb_collect, etc. */
3845 if (!gdb_breakpoint_here (lwp
->stop_pc
)
3846 && lwp
->stop_reason
!= TARGET_STOPPED_BY_WATCHPOINT
3847 && thread
->last_resume_kind
!= resume_step
3848 && maybe_move_out_of_jump_pad (lwp
, wstat
))
3851 debug_printf ("LWP %ld needs stabilizing (in jump pad)\n",
3856 lwp
->status_pending_p
= 0;
3857 enqueue_one_deferred_signal (lwp
, wstat
);
3860 debug_printf ("Signal %d for LWP %ld deferred "
3862 WSTOPSIG (*wstat
), lwpid_of (thread
));
3865 linux_resume_one_lwp (lwp
, 0, 0, NULL
);
3868 lwp_suspended_inc (lwp
);
3870 current_thread
= saved_thread
;
3874 lwp_running (struct inferior_list_entry
*entry
, void *data
)
3876 struct thread_info
*thread
= (struct thread_info
*) entry
;
3877 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3879 if (lwp_is_marked_dead (lwp
))
3886 /* Stop all lwps that aren't stopped yet, except EXCEPT, if not NULL.
3887 If SUSPEND, then also increase the suspend count of every LWP,
3891 stop_all_lwps (int suspend
, struct lwp_info
*except
)
3893 /* Should not be called recursively. */
3894 gdb_assert (stopping_threads
== NOT_STOPPING_THREADS
);
3899 debug_printf ("stop_all_lwps (%s, except=%s)\n",
3900 suspend
? "stop-and-suspend" : "stop",
3902 ? target_pid_to_str (ptid_of (get_lwp_thread (except
)))
3906 stopping_threads
= (suspend
3907 ? STOPPING_AND_SUSPENDING_THREADS
3908 : STOPPING_THREADS
);
3911 find_inferior (&all_threads
, suspend_and_send_sigstop_callback
, except
);
3913 find_inferior (&all_threads
, send_sigstop_callback
, except
);
3914 wait_for_sigstop ();
3915 stopping_threads
= NOT_STOPPING_THREADS
;
3919 debug_printf ("stop_all_lwps done, setting stopping_threads "
3920 "back to !stopping\n");
3925 /* Enqueue one signal in the chain of signals which need to be
3926 delivered to this process on next resume. */
3929 enqueue_pending_signal (struct lwp_info
*lwp
, int signal
, siginfo_t
*info
)
3931 struct pending_signals
*p_sig
= XNEW (struct pending_signals
);
3933 p_sig
->prev
= lwp
->pending_signals
;
3934 p_sig
->signal
= signal
;
3936 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
3938 memcpy (&p_sig
->info
, info
, sizeof (siginfo_t
));
3939 lwp
->pending_signals
= p_sig
;
3942 /* Resume execution of LWP. If STEP is nonzero, single-step it. If
3943 SIGNAL is nonzero, give it that signal. */
3946 linux_resume_one_lwp_throw (struct lwp_info
*lwp
,
3947 int step
, int signal
, siginfo_t
*info
)
3949 struct thread_info
*thread
= get_lwp_thread (lwp
);
3950 struct thread_info
*saved_thread
;
3951 int fast_tp_collecting
;
3952 struct process_info
*proc
= get_thread_process (thread
);
3954 /* Note that target description may not be initialised
3955 (proc->tdesc == NULL) at this point because the program hasn't
3956 stopped at the first instruction yet. It means GDBserver skips
3957 the extra traps from the wrapper program (see option --wrapper).
3958 Code in this function that requires register access should be
3959 guarded by proc->tdesc == NULL or something else. */
3961 if (lwp
->stopped
== 0)
3964 gdb_assert (lwp
->waitstatus
.kind
== TARGET_WAITKIND_IGNORE
);
3966 fast_tp_collecting
= lwp
->collecting_fast_tracepoint
;
3968 gdb_assert (!stabilizing_threads
|| fast_tp_collecting
);
3970 /* Cancel actions that rely on GDB not changing the PC (e.g., the
3971 user used the "jump" command, or "set $pc = foo"). */
3972 if (thread
->while_stepping
!= NULL
&& lwp
->stop_pc
!= get_pc (lwp
))
3974 /* Collecting 'while-stepping' actions doesn't make sense
3976 release_while_stepping_state_list (thread
);
3979 /* If we have pending signals or status, and a new signal, enqueue the
3980 signal. Also enqueue the signal if we are waiting to reinsert a
3981 breakpoint; it will be picked up again below. */
3983 && (lwp
->status_pending_p
3984 || lwp
->pending_signals
!= NULL
3985 || lwp
->bp_reinsert
!= 0
3986 || fast_tp_collecting
))
3988 struct pending_signals
*p_sig
= XNEW (struct pending_signals
);
3990 p_sig
->prev
= lwp
->pending_signals
;
3991 p_sig
->signal
= signal
;
3993 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
3995 memcpy (&p_sig
->info
, info
, sizeof (siginfo_t
));
3996 lwp
->pending_signals
= p_sig
;
3999 if (lwp
->status_pending_p
)
4002 debug_printf ("Not resuming lwp %ld (%s, signal %d, stop %s);"
4003 " has pending status\n",
4004 lwpid_of (thread
), step
? "step" : "continue", signal
,
4005 lwp
->stop_expected
? "expected" : "not expected");
4009 saved_thread
= current_thread
;
4010 current_thread
= thread
;
4013 debug_printf ("Resuming lwp %ld (%s, signal %d, stop %s)\n",
4014 lwpid_of (thread
), step
? "step" : "continue", signal
,
4015 lwp
->stop_expected
? "expected" : "not expected");
4017 /* This bit needs some thinking about. If we get a signal that
4018 we must report while a single-step reinsert is still pending,
4019 we often end up resuming the thread. It might be better to
4020 (ew) allow a stack of pending events; then we could be sure that
4021 the reinsert happened right away and not lose any signals.
4023 Making this stack would also shrink the window in which breakpoints are
4024 uninserted (see comment in linux_wait_for_lwp) but not enough for
4025 complete correctness, so it won't solve that problem. It may be
4026 worthwhile just to solve this one, however. */
4027 if (lwp
->bp_reinsert
!= 0)
4030 debug_printf (" pending reinsert at 0x%s\n",
4031 paddress (lwp
->bp_reinsert
));
4033 if (can_hardware_single_step ())
4035 if (fast_tp_collecting
== 0)
4038 fprintf (stderr
, "BAD - reinserting but not stepping.\n");
4040 fprintf (stderr
, "BAD - reinserting and suspended(%d).\n",
4047 /* Postpone any pending signal. It was enqueued above. */
4051 if (fast_tp_collecting
== 1)
4054 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
4055 " (exit-jump-pad-bkpt)\n",
4058 /* Postpone any pending signal. It was enqueued above. */
4061 else if (fast_tp_collecting
== 2)
4064 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
4065 " single-stepping\n",
4068 if (can_hardware_single_step ())
4072 internal_error (__FILE__
, __LINE__
,
4073 "moving out of jump pad single-stepping"
4074 " not implemented on this target");
4077 /* Postpone any pending signal. It was enqueued above. */
4081 /* If we have while-stepping actions in this thread set it stepping.
4082 If we have a signal to deliver, it may or may not be set to
4083 SIG_IGN, we don't know. Assume so, and allow collecting
4084 while-stepping into a signal handler. A possible smart thing to
4085 do would be to set an internal breakpoint at the signal return
4086 address, continue, and carry on catching this while-stepping
4087 action only when that breakpoint is hit. A future
4089 if (thread
->while_stepping
!= NULL
4090 && can_hardware_single_step ())
4093 debug_printf ("lwp %ld has a while-stepping action -> forcing step.\n",
4098 if (proc
->tdesc
!= NULL
&& the_low_target
.get_pc
!= NULL
)
4100 struct regcache
*regcache
= get_thread_regcache (current_thread
, 1);
4102 lwp
->stop_pc
= (*the_low_target
.get_pc
) (regcache
);
4106 debug_printf (" %s from pc 0x%lx\n", step
? "step" : "continue",
4107 (long) lwp
->stop_pc
);
4111 /* If we have pending signals, consume one unless we are trying to
4112 reinsert a breakpoint or we're trying to finish a fast tracepoint
4114 if (lwp
->pending_signals
!= NULL
4115 && lwp
->bp_reinsert
== 0
4116 && fast_tp_collecting
== 0)
4118 struct pending_signals
**p_sig
;
4120 p_sig
= &lwp
->pending_signals
;
4121 while ((*p_sig
)->prev
!= NULL
)
4122 p_sig
= &(*p_sig
)->prev
;
4124 signal
= (*p_sig
)->signal
;
4125 if ((*p_sig
)->info
.si_signo
!= 0)
4126 ptrace (PTRACE_SETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
4133 if (the_low_target
.prepare_to_resume
!= NULL
)
4134 the_low_target
.prepare_to_resume (lwp
);
4136 regcache_invalidate_thread (thread
);
4138 lwp
->stepping
= step
;
4139 ptrace (step
? PTRACE_SINGLESTEP
: PTRACE_CONT
, lwpid_of (thread
),
4140 (PTRACE_TYPE_ARG3
) 0,
4141 /* Coerce to a uintptr_t first to avoid potential gcc warning
4142 of coercing an 8 byte integer to a 4 byte pointer. */
4143 (PTRACE_TYPE_ARG4
) (uintptr_t) signal
);
4145 current_thread
= saved_thread
;
4147 perror_with_name ("resuming thread");
4149 /* Successfully resumed. Clear state that no longer makes sense,
4150 and mark the LWP as running. Must not do this before resuming
4151 otherwise if that fails other code will be confused. E.g., we'd
4152 later try to stop the LWP and hang forever waiting for a stop
4153 status. Note that we must not throw after this is cleared,
4154 otherwise handle_zombie_lwp_error would get confused. */
4156 lwp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
4159 /* Called when we try to resume a stopped LWP and that errors out. If
4160 the LWP is no longer in ptrace-stopped state (meaning it's zombie,
4161 or about to become), discard the error, clear any pending status
4162 the LWP may have, and return true (we'll collect the exit status
4163 soon enough). Otherwise, return false. */
4166 check_ptrace_stopped_lwp_gone (struct lwp_info
*lp
)
4168 struct thread_info
*thread
= get_lwp_thread (lp
);
4170 /* If we get an error after resuming the LWP successfully, we'd
4171 confuse !T state for the LWP being gone. */
4172 gdb_assert (lp
->stopped
);
4174 /* We can't just check whether the LWP is in 'Z (Zombie)' state,
4175 because even if ptrace failed with ESRCH, the tracee may be "not
4176 yet fully dead", but already refusing ptrace requests. In that
4177 case the tracee has 'R (Running)' state for a little bit
4178 (observed in Linux 3.18). See also the note on ESRCH in the
4179 ptrace(2) man page. Instead, check whether the LWP has any state
4180 other than ptrace-stopped. */
4182 /* Don't assume anything if /proc/PID/status can't be read. */
4183 if (linux_proc_pid_is_trace_stopped_nowarn (lwpid_of (thread
)) == 0)
4185 lp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
4186 lp
->status_pending_p
= 0;
4192 /* Like linux_resume_one_lwp_throw, but no error is thrown if the LWP
4193 disappears while we try to resume it. */
4196 linux_resume_one_lwp (struct lwp_info
*lwp
,
4197 int step
, int signal
, siginfo_t
*info
)
4201 linux_resume_one_lwp_throw (lwp
, step
, signal
, info
);
4203 CATCH (ex
, RETURN_MASK_ERROR
)
4205 if (!check_ptrace_stopped_lwp_gone (lwp
))
4206 throw_exception (ex
);
4211 struct thread_resume_array
4213 struct thread_resume
*resume
;
4217 /* This function is called once per thread via find_inferior.
4218 ARG is a pointer to a thread_resume_array struct.
4219 We look up the thread specified by ENTRY in ARG, and mark the thread
4220 with a pointer to the appropriate resume request.
4222 This algorithm is O(threads * resume elements), but resume elements
4223 is small (and will remain small at least until GDB supports thread
4227 linux_set_resume_request (struct inferior_list_entry
*entry
, void *arg
)
4229 struct thread_info
*thread
= (struct thread_info
*) entry
;
4230 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4232 struct thread_resume_array
*r
;
4234 r
= (struct thread_resume_array
*) arg
;
4236 for (ndx
= 0; ndx
< r
->n
; ndx
++)
4238 ptid_t ptid
= r
->resume
[ndx
].thread
;
4239 if (ptid_equal (ptid
, minus_one_ptid
)
4240 || ptid_equal (ptid
, entry
->id
)
4241 /* Handle both 'pPID' and 'pPID.-1' as meaning 'all threads
4243 || (ptid_get_pid (ptid
) == pid_of (thread
)
4244 && (ptid_is_pid (ptid
)
4245 || ptid_get_lwp (ptid
) == -1)))
4247 if (r
->resume
[ndx
].kind
== resume_stop
4248 && thread
->last_resume_kind
== resume_stop
)
4251 debug_printf ("already %s LWP %ld at GDB's request\n",
4252 (thread
->last_status
.kind
4253 == TARGET_WAITKIND_STOPPED
)
4261 lwp
->resume
= &r
->resume
[ndx
];
4262 thread
->last_resume_kind
= lwp
->resume
->kind
;
4264 lwp
->step_range_start
= lwp
->resume
->step_range_start
;
4265 lwp
->step_range_end
= lwp
->resume
->step_range_end
;
4267 /* If we had a deferred signal to report, dequeue one now.
4268 This can happen if LWP gets more than one signal while
4269 trying to get out of a jump pad. */
4271 && !lwp
->status_pending_p
4272 && dequeue_one_deferred_signal (lwp
, &lwp
->status_pending
))
4274 lwp
->status_pending_p
= 1;
4277 debug_printf ("Dequeueing deferred signal %d for LWP %ld, "
4278 "leaving status pending.\n",
4279 WSTOPSIG (lwp
->status_pending
),
4287 /* No resume action for this thread. */
4293 /* find_inferior callback for linux_resume.
4294 Set *FLAG_P if this lwp has an interesting status pending. */
4297 resume_status_pending_p (struct inferior_list_entry
*entry
, void *flag_p
)
4299 struct thread_info
*thread
= (struct thread_info
*) entry
;
4300 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4302 /* LWPs which will not be resumed are not interesting, because
4303 we might not wait for them next time through linux_wait. */
4304 if (lwp
->resume
== NULL
)
4307 if (thread_still_has_status_pending_p (thread
))
4308 * (int *) flag_p
= 1;
4313 /* Return 1 if this lwp that GDB wants running is stopped at an
4314 internal breakpoint that we need to step over. It assumes that any
4315 required STOP_PC adjustment has already been propagated to the
4316 inferior's regcache. */
4319 need_step_over_p (struct inferior_list_entry
*entry
, void *dummy
)
4321 struct thread_info
*thread
= (struct thread_info
*) entry
;
4322 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4323 struct thread_info
*saved_thread
;
4325 struct process_info
*proc
= get_thread_process (thread
);
4327 /* GDBserver is skipping the extra traps from the wrapper program,
4328 don't have to do step over. */
4329 if (proc
->tdesc
== NULL
)
4332 /* LWPs which will not be resumed are not interesting, because we
4333 might not wait for them next time through linux_wait. */
4338 debug_printf ("Need step over [LWP %ld]? Ignoring, not stopped\n",
4343 if (thread
->last_resume_kind
== resume_stop
)
4346 debug_printf ("Need step over [LWP %ld]? Ignoring, should remain"
4352 gdb_assert (lwp
->suspended
>= 0);
4357 debug_printf ("Need step over [LWP %ld]? Ignoring, suspended\n",
4362 if (!lwp
->need_step_over
)
4365 debug_printf ("Need step over [LWP %ld]? No\n", lwpid_of (thread
));
4368 if (lwp
->status_pending_p
)
4371 debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
4377 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
4381 /* If the PC has changed since we stopped, then don't do anything,
4382 and let the breakpoint/tracepoint be hit. This happens if, for
4383 instance, GDB handled the decr_pc_after_break subtraction itself,
4384 GDB is OOL stepping this thread, or the user has issued a "jump"
4385 command, or poked thread's registers herself. */
4386 if (pc
!= lwp
->stop_pc
)
4389 debug_printf ("Need step over [LWP %ld]? Cancelling, PC was changed. "
4390 "Old stop_pc was 0x%s, PC is now 0x%s\n",
4392 paddress (lwp
->stop_pc
), paddress (pc
));
4394 lwp
->need_step_over
= 0;
4398 saved_thread
= current_thread
;
4399 current_thread
= thread
;
4401 /* We can only step over breakpoints we know about. */
4402 if (breakpoint_here (pc
) || fast_tracepoint_jump_here (pc
))
4404 /* Don't step over a breakpoint that GDB expects to hit
4405 though. If the condition is being evaluated on the target's side
4406 and it evaluate to false, step over this breakpoint as well. */
4407 if (gdb_breakpoint_here (pc
)
4408 && gdb_condition_true_at_breakpoint (pc
)
4409 && gdb_no_commands_at_breakpoint (pc
))
4412 debug_printf ("Need step over [LWP %ld]? yes, but found"
4413 " GDB breakpoint at 0x%s; skipping step over\n",
4414 lwpid_of (thread
), paddress (pc
));
4416 current_thread
= saved_thread
;
4422 debug_printf ("Need step over [LWP %ld]? yes, "
4423 "found breakpoint at 0x%s\n",
4424 lwpid_of (thread
), paddress (pc
));
4426 /* We've found an lwp that needs stepping over --- return 1 so
4427 that find_inferior stops looking. */
4428 current_thread
= saved_thread
;
4430 /* If the step over is cancelled, this is set again. */
4431 lwp
->need_step_over
= 0;
4436 current_thread
= saved_thread
;
4439 debug_printf ("Need step over [LWP %ld]? No, no breakpoint found"
4441 lwpid_of (thread
), paddress (pc
));
4446 /* Start a step-over operation on LWP. When LWP stopped at a
4447 breakpoint, to make progress, we need to remove the breakpoint out
4448 of the way. If we let other threads run while we do that, they may
4449 pass by the breakpoint location and miss hitting it. To avoid
4450 that, a step-over momentarily stops all threads while LWP is
4451 single-stepped while the breakpoint is temporarily uninserted from
4452 the inferior. When the single-step finishes, we reinsert the
4453 breakpoint, and let all threads that are supposed to be running,
4456 On targets that don't support hardware single-step, we don't
4457 currently support full software single-stepping. Instead, we only
4458 support stepping over the thread event breakpoint, by asking the
4459 low target where to place a reinsert breakpoint. Since this
4460 routine assumes the breakpoint being stepped over is a thread event
4461 breakpoint, it usually assumes the return address of the current
4462 function is a good enough place to set the reinsert breakpoint. */
4465 start_step_over (struct lwp_info
*lwp
)
4467 struct thread_info
*thread
= get_lwp_thread (lwp
);
4468 struct thread_info
*saved_thread
;
4473 debug_printf ("Starting step-over on LWP %ld. Stopping all threads\n",
4476 stop_all_lwps (1, lwp
);
4478 if (lwp
->suspended
!= 0)
4480 internal_error (__FILE__
, __LINE__
,
4481 "LWP %ld suspended=%d\n", lwpid_of (thread
),
4486 debug_printf ("Done stopping all threads for step-over.\n");
4488 /* Note, we should always reach here with an already adjusted PC,
4489 either by GDB (if we're resuming due to GDB's request), or by our
4490 caller, if we just finished handling an internal breakpoint GDB
4491 shouldn't care about. */
4494 saved_thread
= current_thread
;
4495 current_thread
= thread
;
4497 lwp
->bp_reinsert
= pc
;
4498 uninsert_breakpoints_at (pc
);
4499 uninsert_fast_tracepoint_jumps_at (pc
);
4501 if (can_hardware_single_step ())
4507 CORE_ADDR raddr
= (*the_low_target
.breakpoint_reinsert_addr
) ();
4508 set_reinsert_breakpoint (raddr
);
4512 current_thread
= saved_thread
;
4514 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
4516 /* Require next event from this LWP. */
4517 step_over_bkpt
= thread
->entry
.id
;
4521 /* Finish a step-over. Reinsert the breakpoint we had uninserted in
4522 start_step_over, if still there, and delete any reinsert
4523 breakpoints we've set, on non hardware single-step targets. */
4526 finish_step_over (struct lwp_info
*lwp
)
4528 if (lwp
->bp_reinsert
!= 0)
4531 debug_printf ("Finished step over.\n");
4533 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
4534 may be no breakpoint to reinsert there by now. */
4535 reinsert_breakpoints_at (lwp
->bp_reinsert
);
4536 reinsert_fast_tracepoint_jumps_at (lwp
->bp_reinsert
);
4538 lwp
->bp_reinsert
= 0;
4540 /* Delete any software-single-step reinsert breakpoints. No
4541 longer needed. We don't have to worry about other threads
4542 hitting this trap, and later not being able to explain it,
4543 because we were stepping over a breakpoint, and we hold all
4544 threads but LWP stopped while doing that. */
4545 if (!can_hardware_single_step ())
4546 delete_reinsert_breakpoints ();
4548 step_over_bkpt
= null_ptid
;
4555 /* If there's a step over in progress, wait until all threads stop
4556 (that is, until the stepping thread finishes its step), and
4557 unsuspend all lwps. The stepping thread ends with its status
4558 pending, which is processed later when we get back to processing
4562 complete_ongoing_step_over (void)
4564 if (!ptid_equal (step_over_bkpt
, null_ptid
))
4566 struct lwp_info
*lwp
;
4571 debug_printf ("detach: step over in progress, finish it first\n");
4573 /* Passing NULL_PTID as filter indicates we want all events to
4574 be left pending. Eventually this returns when there are no
4575 unwaited-for children left. */
4576 ret
= linux_wait_for_event_filtered (minus_one_ptid
, null_ptid
,
4578 gdb_assert (ret
== -1);
4580 lwp
= find_lwp_pid (step_over_bkpt
);
4582 finish_step_over (lwp
);
4583 step_over_bkpt
= null_ptid
;
4584 unsuspend_all_lwps (lwp
);
4588 /* This function is called once per thread. We check the thread's resume
4589 request, which will tell us whether to resume, step, or leave the thread
4590 stopped; and what signal, if any, it should be sent.
4592 For threads which we aren't explicitly told otherwise, we preserve
4593 the stepping flag; this is used for stepping over gdbserver-placed
4596 If pending_flags was set in any thread, we queue any needed
4597 signals, since we won't actually resume. We already have a pending
4598 event to report, so we don't need to preserve any step requests;
4599 they should be re-issued if necessary. */
4602 linux_resume_one_thread (struct inferior_list_entry
*entry
, void *arg
)
4604 struct thread_info
*thread
= (struct thread_info
*) entry
;
4605 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4607 int leave_all_stopped
= * (int *) arg
;
4610 if (lwp
->resume
== NULL
)
4613 if (lwp
->resume
->kind
== resume_stop
)
4616 debug_printf ("resume_stop request for LWP %ld\n", lwpid_of (thread
));
4621 debug_printf ("stopping LWP %ld\n", lwpid_of (thread
));
4623 /* Stop the thread, and wait for the event asynchronously,
4624 through the event loop. */
4630 debug_printf ("already stopped LWP %ld\n",
4633 /* The LWP may have been stopped in an internal event that
4634 was not meant to be notified back to GDB (e.g., gdbserver
4635 breakpoint), so we should be reporting a stop event in
4638 /* If the thread already has a pending SIGSTOP, this is a
4639 no-op. Otherwise, something later will presumably resume
4640 the thread and this will cause it to cancel any pending
4641 operation, due to last_resume_kind == resume_stop. If
4642 the thread already has a pending status to report, we
4643 will still report it the next time we wait - see
4644 status_pending_p_callback. */
4646 /* If we already have a pending signal to report, then
4647 there's no need to queue a SIGSTOP, as this means we're
4648 midway through moving the LWP out of the jumppad, and we
4649 will report the pending signal as soon as that is
4651 if (lwp
->pending_signals_to_report
== NULL
)
4655 /* For stop requests, we're done. */
4657 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
4661 /* If this thread which is about to be resumed has a pending status,
4662 then don't resume it - we can just report the pending status.
4663 Likewise if it is suspended, because e.g., another thread is
4664 stepping past a breakpoint. Make sure to queue any signals that
4665 would otherwise be sent. In all-stop mode, we do this decision
4666 based on if *any* thread has a pending status. If there's a
4667 thread that needs the step-over-breakpoint dance, then don't
4668 resume any other thread but that particular one. */
4669 leave_pending
= (lwp
->suspended
4670 || lwp
->status_pending_p
4671 || leave_all_stopped
);
4676 debug_printf ("resuming LWP %ld\n", lwpid_of (thread
));
4678 step
= (lwp
->resume
->kind
== resume_step
);
4679 linux_resume_one_lwp (lwp
, step
, lwp
->resume
->sig
, NULL
);
4684 debug_printf ("leaving LWP %ld stopped\n", lwpid_of (thread
));
4686 /* If we have a new signal, enqueue the signal. */
4687 if (lwp
->resume
->sig
!= 0)
4689 struct pending_signals
*p_sig
= XCNEW (struct pending_signals
);
4691 p_sig
->prev
= lwp
->pending_signals
;
4692 p_sig
->signal
= lwp
->resume
->sig
;
4694 /* If this is the same signal we were previously stopped by,
4695 make sure to queue its siginfo. We can ignore the return
4696 value of ptrace; if it fails, we'll skip
4697 PTRACE_SETSIGINFO. */
4698 if (WIFSTOPPED (lwp
->last_status
)
4699 && WSTOPSIG (lwp
->last_status
) == lwp
->resume
->sig
)
4700 ptrace (PTRACE_GETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
4703 lwp
->pending_signals
= p_sig
;
4707 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
4713 linux_resume (struct thread_resume
*resume_info
, size_t n
)
4715 struct thread_resume_array array
= { resume_info
, n
};
4716 struct thread_info
*need_step_over
= NULL
;
4718 int leave_all_stopped
;
4723 debug_printf ("linux_resume:\n");
4726 find_inferior (&all_threads
, linux_set_resume_request
, &array
);
4728 /* If there is a thread which would otherwise be resumed, which has
4729 a pending status, then don't resume any threads - we can just
4730 report the pending status. Make sure to queue any signals that
4731 would otherwise be sent. In non-stop mode, we'll apply this
4732 logic to each thread individually. We consume all pending events
4733 before considering to start a step-over (in all-stop). */
4736 find_inferior (&all_threads
, resume_status_pending_p
, &any_pending
);
4738 /* If there is a thread which would otherwise be resumed, which is
4739 stopped at a breakpoint that needs stepping over, then don't
4740 resume any threads - have it step over the breakpoint with all
4741 other threads stopped, then resume all threads again. Make sure
4742 to queue any signals that would otherwise be delivered or
4744 if (!any_pending
&& supports_breakpoints ())
4746 = (struct thread_info
*) find_inferior (&all_threads
,
4747 need_step_over_p
, NULL
);
4749 leave_all_stopped
= (need_step_over
!= NULL
|| any_pending
);
4753 if (need_step_over
!= NULL
)
4754 debug_printf ("Not resuming all, need step over\n");
4755 else if (any_pending
)
4756 debug_printf ("Not resuming, all-stop and found "
4757 "an LWP with pending status\n");
4759 debug_printf ("Resuming, no pending status or step over needed\n");
4762 /* Even if we're leaving threads stopped, queue all signals we'd
4763 otherwise deliver. */
4764 find_inferior (&all_threads
, linux_resume_one_thread
, &leave_all_stopped
);
4767 start_step_over (get_thread_lwp (need_step_over
));
4771 debug_printf ("linux_resume done\n");
4775 /* We may have events that were pending that can/should be sent to
4776 the client now. Trigger a linux_wait call. */
4777 if (target_is_async_p ())
4781 /* This function is called once per thread. We check the thread's
4782 last resume request, which will tell us whether to resume, step, or
4783 leave the thread stopped. Any signal the client requested to be
4784 delivered has already been enqueued at this point.
4786 If any thread that GDB wants running is stopped at an internal
4787 breakpoint that needs stepping over, we start a step-over operation
4788 on that particular thread, and leave all others stopped. */
4791 proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
4793 struct thread_info
*thread
= (struct thread_info
*) entry
;
4794 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4801 debug_printf ("proceed_one_lwp: lwp %ld\n", lwpid_of (thread
));
4806 debug_printf (" LWP %ld already running\n", lwpid_of (thread
));
4810 if (thread
->last_resume_kind
== resume_stop
4811 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
4814 debug_printf (" client wants LWP to remain %ld stopped\n",
4819 if (lwp
->status_pending_p
)
4822 debug_printf (" LWP %ld has pending status, leaving stopped\n",
4827 gdb_assert (lwp
->suspended
>= 0);
4832 debug_printf (" LWP %ld is suspended\n", lwpid_of (thread
));
4836 if (thread
->last_resume_kind
== resume_stop
4837 && lwp
->pending_signals_to_report
== NULL
4838 && lwp
->collecting_fast_tracepoint
== 0)
4840 /* We haven't reported this LWP as stopped yet (otherwise, the
4841 last_status.kind check above would catch it, and we wouldn't
4842 reach here. This LWP may have been momentarily paused by a
4843 stop_all_lwps call while handling for example, another LWP's
4844 step-over. In that case, the pending expected SIGSTOP signal
4845 that was queued at vCont;t handling time will have already
4846 been consumed by wait_for_sigstop, and so we need to requeue
4847 another one here. Note that if the LWP already has a SIGSTOP
4848 pending, this is a no-op. */
4851 debug_printf ("Client wants LWP %ld to stop. "
4852 "Making sure it has a SIGSTOP pending\n",
4858 if (thread
->last_resume_kind
== resume_step
)
4861 debug_printf (" stepping LWP %ld, client wants it stepping\n",
4865 else if (lwp
->bp_reinsert
!= 0)
4868 debug_printf (" stepping LWP %ld, reinsert set\n",
4875 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
4880 unsuspend_and_proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
4882 struct thread_info
*thread
= (struct thread_info
*) entry
;
4883 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4888 lwp_suspended_decr (lwp
);
4890 return proceed_one_lwp (entry
, except
);
4893 /* When we finish a step-over, set threads running again. If there's
4894 another thread that may need a step-over, now's the time to start
4895 it. Eventually, we'll move all threads past their breakpoints. */
4898 proceed_all_lwps (void)
4900 struct thread_info
*need_step_over
;
4902 /* If there is a thread which would otherwise be resumed, which is
4903 stopped at a breakpoint that needs stepping over, then don't
4904 resume any threads - have it step over the breakpoint with all
4905 other threads stopped, then resume all threads again. */
4907 if (supports_breakpoints ())
4910 = (struct thread_info
*) find_inferior (&all_threads
,
4911 need_step_over_p
, NULL
);
4913 if (need_step_over
!= NULL
)
4916 debug_printf ("proceed_all_lwps: found "
4917 "thread %ld needing a step-over\n",
4918 lwpid_of (need_step_over
));
4920 start_step_over (get_thread_lwp (need_step_over
));
4926 debug_printf ("Proceeding, no step-over needed\n");
4928 find_inferior (&all_threads
, proceed_one_lwp
, NULL
);
4931 /* Stopped LWPs that the client wanted to be running, that don't have
4932 pending statuses, are set to run again, except for EXCEPT, if not
4933 NULL. This undoes a stop_all_lwps call. */
4936 unstop_all_lwps (int unsuspend
, struct lwp_info
*except
)
4942 debug_printf ("unstopping all lwps, except=(LWP %ld)\n",
4943 lwpid_of (get_lwp_thread (except
)));
4945 debug_printf ("unstopping all lwps\n");
4949 find_inferior (&all_threads
, unsuspend_and_proceed_one_lwp
, except
);
4951 find_inferior (&all_threads
, proceed_one_lwp
, except
);
4955 debug_printf ("unstop_all_lwps done\n");
4961 #ifdef HAVE_LINUX_REGSETS
4963 #define use_linux_regsets 1
4965 /* Returns true if REGSET has been disabled. */
4968 regset_disabled (struct regsets_info
*info
, struct regset_info
*regset
)
4970 return (info
->disabled_regsets
!= NULL
4971 && info
->disabled_regsets
[regset
- info
->regsets
]);
4974 /* Disable REGSET. */
4977 disable_regset (struct regsets_info
*info
, struct regset_info
*regset
)
4981 dr_offset
= regset
- info
->regsets
;
4982 if (info
->disabled_regsets
== NULL
)
4983 info
->disabled_regsets
= (char *) xcalloc (1, info
->num_regsets
);
4984 info
->disabled_regsets
[dr_offset
] = 1;
4988 regsets_fetch_inferior_registers (struct regsets_info
*regsets_info
,
4989 struct regcache
*regcache
)
4991 struct regset_info
*regset
;
4992 int saw_general_regs
= 0;
4996 pid
= lwpid_of (current_thread
);
4997 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
5002 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
))
5005 buf
= xmalloc (regset
->size
);
5007 nt_type
= regset
->nt_type
;
5011 iov
.iov_len
= regset
->size
;
5012 data
= (void *) &iov
;
5018 res
= ptrace (regset
->get_request
, pid
,
5019 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5021 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
5027 /* If we get EIO on a regset, do not try it again for
5028 this process mode. */
5029 disable_regset (regsets_info
, regset
);
5031 else if (errno
== ENODATA
)
5033 /* ENODATA may be returned if the regset is currently
5034 not "active". This can happen in normal operation,
5035 so suppress the warning in this case. */
5040 sprintf (s
, "ptrace(regsets_fetch_inferior_registers) PID=%d",
5047 if (regset
->type
== GENERAL_REGS
)
5048 saw_general_regs
= 1;
5049 regset
->store_function (regcache
, buf
);
5053 if (saw_general_regs
)
5060 regsets_store_inferior_registers (struct regsets_info
*regsets_info
,
5061 struct regcache
*regcache
)
5063 struct regset_info
*regset
;
5064 int saw_general_regs
= 0;
5068 pid
= lwpid_of (current_thread
);
5069 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
5074 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
)
5075 || regset
->fill_function
== NULL
)
5078 buf
= xmalloc (regset
->size
);
5080 /* First fill the buffer with the current register set contents,
5081 in case there are any items in the kernel's regset that are
5082 not in gdbserver's regcache. */
5084 nt_type
= regset
->nt_type
;
5088 iov
.iov_len
= regset
->size
;
5089 data
= (void *) &iov
;
5095 res
= ptrace (regset
->get_request
, pid
,
5096 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5098 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
5103 /* Then overlay our cached registers on that. */
5104 regset
->fill_function (regcache
, buf
);
5106 /* Only now do we write the register set. */
5108 res
= ptrace (regset
->set_request
, pid
,
5109 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5111 res
= ptrace (regset
->set_request
, pid
, data
, nt_type
);
5119 /* If we get EIO on a regset, do not try it again for
5120 this process mode. */
5121 disable_regset (regsets_info
, regset
);
5123 else if (errno
== ESRCH
)
5125 /* At this point, ESRCH should mean the process is
5126 already gone, in which case we simply ignore attempts
5127 to change its registers. See also the related
5128 comment in linux_resume_one_lwp. */
5134 perror ("Warning: ptrace(regsets_store_inferior_registers)");
5137 else if (regset
->type
== GENERAL_REGS
)
5138 saw_general_regs
= 1;
5141 if (saw_general_regs
)
5147 #else /* !HAVE_LINUX_REGSETS */
5149 #define use_linux_regsets 0
5150 #define regsets_fetch_inferior_registers(regsets_info, regcache) 1
5151 #define regsets_store_inferior_registers(regsets_info, regcache) 1
5155 /* Return 1 if register REGNO is supported by one of the regset ptrace
5156 calls or 0 if it has to be transferred individually. */
5159 linux_register_in_regsets (const struct regs_info
*regs_info
, int regno
)
5161 unsigned char mask
= 1 << (regno
% 8);
5162 size_t index
= regno
/ 8;
5164 return (use_linux_regsets
5165 && (regs_info
->regset_bitmap
== NULL
5166 || (regs_info
->regset_bitmap
[index
] & mask
) != 0));
5169 #ifdef HAVE_LINUX_USRREGS
5172 register_addr (const struct usrregs_info
*usrregs
, int regnum
)
5176 if (regnum
< 0 || regnum
>= usrregs
->num_regs
)
5177 error ("Invalid register number %d.", regnum
);
5179 addr
= usrregs
->regmap
[regnum
];
5184 /* Fetch one register. */
5186 fetch_register (const struct usrregs_info
*usrregs
,
5187 struct regcache
*regcache
, int regno
)
5194 if (regno
>= usrregs
->num_regs
)
5196 if ((*the_low_target
.cannot_fetch_register
) (regno
))
5199 regaddr
= register_addr (usrregs
, regno
);
5203 size
= ((register_size (regcache
->tdesc
, regno
)
5204 + sizeof (PTRACE_XFER_TYPE
) - 1)
5205 & -sizeof (PTRACE_XFER_TYPE
));
5206 buf
= (char *) alloca (size
);
5208 pid
= lwpid_of (current_thread
);
5209 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
5212 *(PTRACE_XFER_TYPE
*) (buf
+ i
) =
5213 ptrace (PTRACE_PEEKUSER
, pid
,
5214 /* Coerce to a uintptr_t first to avoid potential gcc warning
5215 of coercing an 8 byte integer to a 4 byte pointer. */
5216 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
, (PTRACE_TYPE_ARG4
) 0);
5217 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
5219 error ("reading register %d: %s", regno
, strerror (errno
));
5222 if (the_low_target
.supply_ptrace_register
)
5223 the_low_target
.supply_ptrace_register (regcache
, regno
, buf
);
5225 supply_register (regcache
, regno
, buf
);
5228 /* Store one register. */
5230 store_register (const struct usrregs_info
*usrregs
,
5231 struct regcache
*regcache
, int regno
)
5238 if (regno
>= usrregs
->num_regs
)
5240 if ((*the_low_target
.cannot_store_register
) (regno
))
5243 regaddr
= register_addr (usrregs
, regno
);
5247 size
= ((register_size (regcache
->tdesc
, regno
)
5248 + sizeof (PTRACE_XFER_TYPE
) - 1)
5249 & -sizeof (PTRACE_XFER_TYPE
));
5250 buf
= (char *) alloca (size
);
5251 memset (buf
, 0, size
);
5253 if (the_low_target
.collect_ptrace_register
)
5254 the_low_target
.collect_ptrace_register (regcache
, regno
, buf
);
5256 collect_register (regcache
, regno
, buf
);
5258 pid
= lwpid_of (current_thread
);
5259 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
5262 ptrace (PTRACE_POKEUSER
, pid
,
5263 /* Coerce to a uintptr_t first to avoid potential gcc warning
5264 about coercing an 8 byte integer to a 4 byte pointer. */
5265 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
,
5266 (PTRACE_TYPE_ARG4
) *(PTRACE_XFER_TYPE
*) (buf
+ i
));
5269 /* At this point, ESRCH should mean the process is
5270 already gone, in which case we simply ignore attempts
5271 to change its registers. See also the related
5272 comment in linux_resume_one_lwp. */
5276 if ((*the_low_target
.cannot_store_register
) (regno
) == 0)
5277 error ("writing register %d: %s", regno
, strerror (errno
));
5279 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
5283 /* Fetch all registers, or just one, from the child process.
5284 If REGNO is -1, do this for all registers, skipping any that are
5285 assumed to have been retrieved by regsets_fetch_inferior_registers,
5286 unless ALL is non-zero.
5287 Otherwise, REGNO specifies which register (so we can save time). */
5289 usr_fetch_inferior_registers (const struct regs_info
*regs_info
,
5290 struct regcache
*regcache
, int regno
, int all
)
5292 struct usrregs_info
*usr
= regs_info
->usrregs
;
5296 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
5297 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
5298 fetch_register (usr
, regcache
, regno
);
5301 fetch_register (usr
, regcache
, regno
);
5304 /* Store our register values back into the inferior.
5305 If REGNO is -1, do this for all registers, skipping any that are
5306 assumed to have been saved by regsets_store_inferior_registers,
5307 unless ALL is non-zero.
5308 Otherwise, REGNO specifies which register (so we can save time). */
5310 usr_store_inferior_registers (const struct regs_info
*regs_info
,
5311 struct regcache
*regcache
, int regno
, int all
)
5313 struct usrregs_info
*usr
= regs_info
->usrregs
;
5317 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
5318 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
5319 store_register (usr
, regcache
, regno
);
5322 store_register (usr
, regcache
, regno
);
5325 #else /* !HAVE_LINUX_USRREGS */
5327 #define usr_fetch_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
5328 #define usr_store_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
5334 linux_fetch_registers (struct regcache
*regcache
, int regno
)
5338 const struct regs_info
*regs_info
= (*the_low_target
.regs_info
) ();
5342 if (the_low_target
.fetch_register
!= NULL
5343 && regs_info
->usrregs
!= NULL
)
5344 for (regno
= 0; regno
< regs_info
->usrregs
->num_regs
; regno
++)
5345 (*the_low_target
.fetch_register
) (regcache
, regno
);
5347 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
, regcache
);
5348 if (regs_info
->usrregs
!= NULL
)
5349 usr_fetch_inferior_registers (regs_info
, regcache
, -1, all
);
5353 if (the_low_target
.fetch_register
!= NULL
5354 && (*the_low_target
.fetch_register
) (regcache
, regno
))
5357 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
5359 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
,
5361 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
5362 usr_fetch_inferior_registers (regs_info
, regcache
, regno
, 1);
5367 linux_store_registers (struct regcache
*regcache
, int regno
)
5371 const struct regs_info
*regs_info
= (*the_low_target
.regs_info
) ();
5375 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
5377 if (regs_info
->usrregs
!= NULL
)
5378 usr_store_inferior_registers (regs_info
, regcache
, regno
, all
);
5382 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
5384 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
5386 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
5387 usr_store_inferior_registers (regs_info
, regcache
, regno
, 1);
5392 /* Copy LEN bytes from inferior's memory starting at MEMADDR
5393 to debugger memory starting at MYADDR. */
5396 linux_read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
, int len
)
5398 int pid
= lwpid_of (current_thread
);
5399 register PTRACE_XFER_TYPE
*buffer
;
5400 register CORE_ADDR addr
;
5407 /* Try using /proc. Don't bother for one word. */
5408 if (len
>= 3 * sizeof (long))
5412 /* We could keep this file open and cache it - possibly one per
5413 thread. That requires some juggling, but is even faster. */
5414 sprintf (filename
, "/proc/%d/mem", pid
);
5415 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
5419 /* If pread64 is available, use it. It's faster if the kernel
5420 supports it (only one syscall), and it's 64-bit safe even on
5421 32-bit platforms (for instance, SPARC debugging a SPARC64
5424 bytes
= pread64 (fd
, myaddr
, len
, memaddr
);
5427 if (lseek (fd
, memaddr
, SEEK_SET
) != -1)
5428 bytes
= read (fd
, myaddr
, len
);
5435 /* Some data was read, we'll try to get the rest with ptrace. */
5445 /* Round starting address down to longword boundary. */
5446 addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
5447 /* Round ending address up; get number of longwords that makes. */
5448 count
= ((((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
5449 / sizeof (PTRACE_XFER_TYPE
));
5450 /* Allocate buffer of that many longwords. */
5451 buffer
= XALLOCAVEC (PTRACE_XFER_TYPE
, count
);
5453 /* Read all the longwords */
5455 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
5457 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5458 about coercing an 8 byte integer to a 4 byte pointer. */
5459 buffer
[i
] = ptrace (PTRACE_PEEKTEXT
, pid
,
5460 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5461 (PTRACE_TYPE_ARG4
) 0);
5467 /* Copy appropriate bytes out of the buffer. */
5470 i
*= sizeof (PTRACE_XFER_TYPE
);
5471 i
-= memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1);
5473 (char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
5480 /* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
5481 memory at MEMADDR. On failure (cannot write to the inferior)
5482 returns the value of errno. Always succeeds if LEN is zero. */
5485 linux_write_memory (CORE_ADDR memaddr
, const unsigned char *myaddr
, int len
)
5488 /* Round starting address down to longword boundary. */
5489 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
5490 /* Round ending address up; get number of longwords that makes. */
5492 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
5493 / sizeof (PTRACE_XFER_TYPE
);
5495 /* Allocate buffer of that many longwords. */
5496 register PTRACE_XFER_TYPE
*buffer
= XALLOCAVEC (PTRACE_XFER_TYPE
, count
);
5498 int pid
= lwpid_of (current_thread
);
5502 /* Zero length write always succeeds. */
5508 /* Dump up to four bytes. */
5509 char str
[4 * 2 + 1];
5511 int dump
= len
< 4 ? len
: 4;
5513 for (i
= 0; i
< dump
; i
++)
5515 sprintf (p
, "%02x", myaddr
[i
]);
5520 debug_printf ("Writing %s to 0x%08lx in process %d\n",
5521 str
, (long) memaddr
, pid
);
5524 /* Fill start and end extra bytes of buffer with existing memory data. */
5527 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5528 about coercing an 8 byte integer to a 4 byte pointer. */
5529 buffer
[0] = ptrace (PTRACE_PEEKTEXT
, pid
,
5530 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5531 (PTRACE_TYPE_ARG4
) 0);
5539 = ptrace (PTRACE_PEEKTEXT
, pid
,
5540 /* Coerce to a uintptr_t first to avoid potential gcc warning
5541 about coercing an 8 byte integer to a 4 byte pointer. */
5542 (PTRACE_TYPE_ARG3
) (uintptr_t) (addr
+ (count
- 1)
5543 * sizeof (PTRACE_XFER_TYPE
)),
5544 (PTRACE_TYPE_ARG4
) 0);
5549 /* Copy data to be written over corresponding part of buffer. */
5551 memcpy ((char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
5554 /* Write the entire buffer. */
5556 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
5559 ptrace (PTRACE_POKETEXT
, pid
,
5560 /* Coerce to a uintptr_t first to avoid potential gcc warning
5561 about coercing an 8 byte integer to a 4 byte pointer. */
5562 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5563 (PTRACE_TYPE_ARG4
) buffer
[i
]);
5572 linux_look_up_symbols (void)
5574 #ifdef USE_THREAD_DB
5575 struct process_info
*proc
= current_process ();
5577 if (proc
->priv
->thread_db
!= NULL
)
5580 /* If the kernel supports tracing clones, then we don't need to
5581 use the magic thread event breakpoint to learn about
5583 thread_db_init (!linux_supports_traceclone ());
5588 linux_request_interrupt (void)
5590 extern unsigned long signal_pid
;
5592 /* Send a SIGINT to the process group. This acts just like the user
5593 typed a ^C on the controlling terminal. */
5594 kill (-signal_pid
, SIGINT
);
5597 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
5598 to debugger memory starting at MYADDR. */
5601 linux_read_auxv (CORE_ADDR offset
, unsigned char *myaddr
, unsigned int len
)
5603 char filename
[PATH_MAX
];
5605 int pid
= lwpid_of (current_thread
);
5607 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
5609 fd
= open (filename
, O_RDONLY
);
5613 if (offset
!= (CORE_ADDR
) 0
5614 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
5617 n
= read (fd
, myaddr
, len
);
5624 /* These breakpoint and watchpoint related wrapper functions simply
5625 pass on the function call if the target has registered a
5626 corresponding function. */
5629 linux_supports_z_point_type (char z_type
)
5631 return (the_low_target
.supports_z_point_type
!= NULL
5632 && the_low_target
.supports_z_point_type (z_type
));
5636 linux_insert_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
5637 int size
, struct raw_breakpoint
*bp
)
5639 if (type
== raw_bkpt_type_sw
)
5640 return insert_memory_breakpoint (bp
);
5641 else if (the_low_target
.insert_point
!= NULL
)
5642 return the_low_target
.insert_point (type
, addr
, size
, bp
);
5644 /* Unsupported (see target.h). */
5649 linux_remove_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
5650 int size
, struct raw_breakpoint
*bp
)
5652 if (type
== raw_bkpt_type_sw
)
5653 return remove_memory_breakpoint (bp
);
5654 else if (the_low_target
.remove_point
!= NULL
)
5655 return the_low_target
.remove_point (type
, addr
, size
, bp
);
5657 /* Unsupported (see target.h). */
5661 /* Implement the to_stopped_by_sw_breakpoint target_ops
5665 linux_stopped_by_sw_breakpoint (void)
5667 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5669 return (lwp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
);
5672 /* Implement the to_supports_stopped_by_sw_breakpoint target_ops
5676 linux_supports_stopped_by_sw_breakpoint (void)
5678 return USE_SIGTRAP_SIGINFO
;
5681 /* Implement the to_stopped_by_hw_breakpoint target_ops
5685 linux_stopped_by_hw_breakpoint (void)
5687 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5689 return (lwp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
);
5692 /* Implement the to_supports_stopped_by_hw_breakpoint target_ops
5696 linux_supports_stopped_by_hw_breakpoint (void)
5698 return USE_SIGTRAP_SIGINFO
;
5701 /* Implement the supports_hardware_single_step target_ops method. */
5704 linux_supports_hardware_single_step (void)
5706 return can_hardware_single_step ();
5710 linux_stopped_by_watchpoint (void)
5712 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5714 return lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
;
5718 linux_stopped_data_address (void)
5720 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5722 return lwp
->stopped_data_address
;
5725 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
5726 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
5727 && defined(PT_TEXT_END_ADDR)
5729 /* This is only used for targets that define PT_TEXT_ADDR,
5730 PT_DATA_ADDR and PT_TEXT_END_ADDR. If those are not defined, supposedly
5731 the target has different ways of acquiring this information, like
5734 /* Under uClinux, programs are loaded at non-zero offsets, which we need
5735 to tell gdb about. */
5738 linux_read_offsets (CORE_ADDR
*text_p
, CORE_ADDR
*data_p
)
5740 unsigned long text
, text_end
, data
;
5741 int pid
= lwpid_of (current_thread
);
5745 text
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_ADDR
,
5746 (PTRACE_TYPE_ARG4
) 0);
5747 text_end
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_END_ADDR
,
5748 (PTRACE_TYPE_ARG4
) 0);
5749 data
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_DATA_ADDR
,
5750 (PTRACE_TYPE_ARG4
) 0);
5754 /* Both text and data offsets produced at compile-time (and so
5755 used by gdb) are relative to the beginning of the program,
5756 with the data segment immediately following the text segment.
5757 However, the actual runtime layout in memory may put the data
5758 somewhere else, so when we send gdb a data base-address, we
5759 use the real data base address and subtract the compile-time
5760 data base-address from it (which is just the length of the
5761 text segment). BSS immediately follows data in both
5764 *data_p
= data
- (text_end
- text
);
5773 linux_qxfer_osdata (const char *annex
,
5774 unsigned char *readbuf
, unsigned const char *writebuf
,
5775 CORE_ADDR offset
, int len
)
5777 return linux_common_xfer_osdata (annex
, readbuf
, offset
, len
);
5780 /* Convert a native/host siginfo object, into/from the siginfo in the
5781 layout of the inferiors' architecture. */
5784 siginfo_fixup (siginfo_t
*siginfo
, void *inf_siginfo
, int direction
)
5788 if (the_low_target
.siginfo_fixup
!= NULL
)
5789 done
= the_low_target
.siginfo_fixup (siginfo
, inf_siginfo
, direction
);
5791 /* If there was no callback, or the callback didn't do anything,
5792 then just do a straight memcpy. */
5796 memcpy (siginfo
, inf_siginfo
, sizeof (siginfo_t
));
5798 memcpy (inf_siginfo
, siginfo
, sizeof (siginfo_t
));
5803 linux_xfer_siginfo (const char *annex
, unsigned char *readbuf
,
5804 unsigned const char *writebuf
, CORE_ADDR offset
, int len
)
5808 char inf_siginfo
[sizeof (siginfo_t
)];
5810 if (current_thread
== NULL
)
5813 pid
= lwpid_of (current_thread
);
5816 debug_printf ("%s siginfo for lwp %d.\n",
5817 readbuf
!= NULL
? "Reading" : "Writing",
5820 if (offset
>= sizeof (siginfo
))
5823 if (ptrace (PTRACE_GETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
5826 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
5827 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
5828 inferior with a 64-bit GDBSERVER should look the same as debugging it
5829 with a 32-bit GDBSERVER, we need to convert it. */
5830 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
5832 if (offset
+ len
> sizeof (siginfo
))
5833 len
= sizeof (siginfo
) - offset
;
5835 if (readbuf
!= NULL
)
5836 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
5839 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
5841 /* Convert back to ptrace layout before flushing it out. */
5842 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
5844 if (ptrace (PTRACE_SETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
5851 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
5852 so we notice when children change state; as the handler for the
5853 sigsuspend in my_waitpid. */
5856 sigchld_handler (int signo
)
5858 int old_errno
= errno
;
5864 /* fprintf is not async-signal-safe, so call write
5866 if (write (2, "sigchld_handler\n",
5867 sizeof ("sigchld_handler\n") - 1) < 0)
5868 break; /* just ignore */
5872 if (target_is_async_p ())
5873 async_file_mark (); /* trigger a linux_wait */
5879 linux_supports_non_stop (void)
5885 linux_async (int enable
)
5887 int previous
= target_is_async_p ();
5890 debug_printf ("linux_async (%d), previous=%d\n",
5893 if (previous
!= enable
)
5896 sigemptyset (&mask
);
5897 sigaddset (&mask
, SIGCHLD
);
5899 sigprocmask (SIG_BLOCK
, &mask
, NULL
);
5903 if (pipe (linux_event_pipe
) == -1)
5905 linux_event_pipe
[0] = -1;
5906 linux_event_pipe
[1] = -1;
5907 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
5909 warning ("creating event pipe failed.");
5913 fcntl (linux_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
5914 fcntl (linux_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
5916 /* Register the event loop handler. */
5917 add_file_handler (linux_event_pipe
[0],
5918 handle_target_event
, NULL
);
5920 /* Always trigger a linux_wait. */
5925 delete_file_handler (linux_event_pipe
[0]);
5927 close (linux_event_pipe
[0]);
5928 close (linux_event_pipe
[1]);
5929 linux_event_pipe
[0] = -1;
5930 linux_event_pipe
[1] = -1;
5933 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
5940 linux_start_non_stop (int nonstop
)
5942 /* Register or unregister from event-loop accordingly. */
5943 linux_async (nonstop
);
5945 if (target_is_async_p () != (nonstop
!= 0))
5952 linux_supports_multi_process (void)
5957 /* Check if fork events are supported. */
5960 linux_supports_fork_events (void)
5962 return linux_supports_tracefork ();
5965 /* Check if vfork events are supported. */
5968 linux_supports_vfork_events (void)
5970 return linux_supports_tracefork ();
5973 /* Check if exec events are supported. */
5976 linux_supports_exec_events (void)
5978 return linux_supports_traceexec ();
5981 /* Callback for 'find_inferior'. Set the (possibly changed) ptrace
5982 options for the specified lwp. */
5985 reset_lwp_ptrace_options_callback (struct inferior_list_entry
*entry
,
5988 struct thread_info
*thread
= (struct thread_info
*) entry
;
5989 struct lwp_info
*lwp
= get_thread_lwp (thread
);
5993 /* Stop the lwp so we can modify its ptrace options. */
5994 lwp
->must_set_ptrace_flags
= 1;
5995 linux_stop_lwp (lwp
);
5999 /* Already stopped; go ahead and set the ptrace options. */
6000 struct process_info
*proc
= find_process_pid (pid_of (thread
));
6001 int options
= linux_low_ptrace_options (proc
->attached
);
6003 linux_enable_event_reporting (lwpid_of (thread
), options
);
6004 lwp
->must_set_ptrace_flags
= 0;
6010 /* Target hook for 'handle_new_gdb_connection'. Causes a reset of the
6011 ptrace flags for all inferiors. This is in case the new GDB connection
6012 doesn't support the same set of events that the previous one did. */
6015 linux_handle_new_gdb_connection (void)
6019 /* Request that all the lwps reset their ptrace options. */
6020 find_inferior (&all_threads
, reset_lwp_ptrace_options_callback
, &pid
);
6024 linux_supports_disable_randomization (void)
6026 #ifdef HAVE_PERSONALITY
6034 linux_supports_agent (void)
6040 linux_supports_range_stepping (void)
6042 if (*the_low_target
.supports_range_stepping
== NULL
)
6045 return (*the_low_target
.supports_range_stepping
) ();
6048 /* Enumerate spufs IDs for process PID. */
6050 spu_enumerate_spu_ids (long pid
, unsigned char *buf
, CORE_ADDR offset
, int len
)
6056 struct dirent
*entry
;
6058 sprintf (path
, "/proc/%ld/fd", pid
);
6059 dir
= opendir (path
);
6064 while ((entry
= readdir (dir
)) != NULL
)
6070 fd
= atoi (entry
->d_name
);
6074 sprintf (path
, "/proc/%ld/fd/%d", pid
, fd
);
6075 if (stat (path
, &st
) != 0)
6077 if (!S_ISDIR (st
.st_mode
))
6080 if (statfs (path
, &stfs
) != 0)
6082 if (stfs
.f_type
!= SPUFS_MAGIC
)
6085 if (pos
>= offset
&& pos
+ 4 <= offset
+ len
)
6087 *(unsigned int *)(buf
+ pos
- offset
) = fd
;
6097 /* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
6098 object type, using the /proc file system. */
6100 linux_qxfer_spu (const char *annex
, unsigned char *readbuf
,
6101 unsigned const char *writebuf
,
6102 CORE_ADDR offset
, int len
)
6104 long pid
= lwpid_of (current_thread
);
6109 if (!writebuf
&& !readbuf
)
6117 return spu_enumerate_spu_ids (pid
, readbuf
, offset
, len
);
6120 sprintf (buf
, "/proc/%ld/fd/%s", pid
, annex
);
6121 fd
= open (buf
, writebuf
? O_WRONLY
: O_RDONLY
);
6126 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
6133 ret
= write (fd
, writebuf
, (size_t) len
);
6135 ret
= read (fd
, readbuf
, (size_t) len
);
6141 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
6142 struct target_loadseg
6144 /* Core address to which the segment is mapped. */
6146 /* VMA recorded in the program header. */
6148 /* Size of this segment in memory. */
6152 # if defined PT_GETDSBT
6153 struct target_loadmap
6155 /* Protocol version number, must be zero. */
6157 /* Pointer to the DSBT table, its size, and the DSBT index. */
6158 unsigned *dsbt_table
;
6159 unsigned dsbt_size
, dsbt_index
;
6160 /* Number of segments in this map. */
6162 /* The actual memory map. */
6163 struct target_loadseg segs
[/*nsegs*/];
6165 # define LINUX_LOADMAP PT_GETDSBT
6166 # define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
6167 # define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
6169 struct target_loadmap
6171 /* Protocol version number, must be zero. */
6173 /* Number of segments in this map. */
6175 /* The actual memory map. */
6176 struct target_loadseg segs
[/*nsegs*/];
6178 # define LINUX_LOADMAP PTRACE_GETFDPIC
6179 # define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
6180 # define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
6184 linux_read_loadmap (const char *annex
, CORE_ADDR offset
,
6185 unsigned char *myaddr
, unsigned int len
)
6187 int pid
= lwpid_of (current_thread
);
6189 struct target_loadmap
*data
= NULL
;
6190 unsigned int actual_length
, copy_length
;
6192 if (strcmp (annex
, "exec") == 0)
6193 addr
= (int) LINUX_LOADMAP_EXEC
;
6194 else if (strcmp (annex
, "interp") == 0)
6195 addr
= (int) LINUX_LOADMAP_INTERP
;
6199 if (ptrace (LINUX_LOADMAP
, pid
, addr
, &data
) != 0)
6205 actual_length
= sizeof (struct target_loadmap
)
6206 + sizeof (struct target_loadseg
) * data
->nsegs
;
6208 if (offset
< 0 || offset
> actual_length
)
6211 copy_length
= actual_length
- offset
< len
? actual_length
- offset
: len
;
6212 memcpy (myaddr
, (char *) data
+ offset
, copy_length
);
6216 # define linux_read_loadmap NULL
6217 #endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
6220 linux_process_qsupported (char **features
, int count
)
6222 if (the_low_target
.process_qsupported
!= NULL
)
6223 the_low_target
.process_qsupported (features
, count
);
6227 linux_supports_tracepoints (void)
6229 if (*the_low_target
.supports_tracepoints
== NULL
)
6232 return (*the_low_target
.supports_tracepoints
) ();
6236 linux_read_pc (struct regcache
*regcache
)
6238 if (the_low_target
.get_pc
== NULL
)
6241 return (*the_low_target
.get_pc
) (regcache
);
6245 linux_write_pc (struct regcache
*regcache
, CORE_ADDR pc
)
6247 gdb_assert (the_low_target
.set_pc
!= NULL
);
6249 (*the_low_target
.set_pc
) (regcache
, pc
);
6253 linux_thread_stopped (struct thread_info
*thread
)
6255 return get_thread_lwp (thread
)->stopped
;
6258 /* This exposes stop-all-threads functionality to other modules. */
6261 linux_pause_all (int freeze
)
6263 stop_all_lwps (freeze
, NULL
);
6266 /* This exposes unstop-all-threads functionality to other gdbserver
6270 linux_unpause_all (int unfreeze
)
6272 unstop_all_lwps (unfreeze
, NULL
);
6276 linux_prepare_to_access_memory (void)
6278 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6281 linux_pause_all (1);
6286 linux_done_accessing_memory (void)
6288 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6291 linux_unpause_all (1);
6295 linux_install_fast_tracepoint_jump_pad (CORE_ADDR tpoint
, CORE_ADDR tpaddr
,
6296 CORE_ADDR collector
,
6299 CORE_ADDR
*jump_entry
,
6300 CORE_ADDR
*trampoline
,
6301 ULONGEST
*trampoline_size
,
6302 unsigned char *jjump_pad_insn
,
6303 ULONGEST
*jjump_pad_insn_size
,
6304 CORE_ADDR
*adjusted_insn_addr
,
6305 CORE_ADDR
*adjusted_insn_addr_end
,
6308 return (*the_low_target
.install_fast_tracepoint_jump_pad
)
6309 (tpoint
, tpaddr
, collector
, lockaddr
, orig_size
,
6310 jump_entry
, trampoline
, trampoline_size
,
6311 jjump_pad_insn
, jjump_pad_insn_size
,
6312 adjusted_insn_addr
, adjusted_insn_addr_end
,
6316 static struct emit_ops
*
6317 linux_emit_ops (void)
6319 if (the_low_target
.emit_ops
!= NULL
)
6320 return (*the_low_target
.emit_ops
) ();
6326 linux_get_min_fast_tracepoint_insn_len (void)
6328 return (*the_low_target
.get_min_fast_tracepoint_insn_len
) ();
6331 /* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
6334 get_phdr_phnum_from_proc_auxv (const int pid
, const int is_elf64
,
6335 CORE_ADDR
*phdr_memaddr
, int *num_phdr
)
6337 char filename
[PATH_MAX
];
6339 const int auxv_size
= is_elf64
6340 ? sizeof (Elf64_auxv_t
) : sizeof (Elf32_auxv_t
);
6341 char buf
[sizeof (Elf64_auxv_t
)]; /* The larger of the two. */
6343 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
6345 fd
= open (filename
, O_RDONLY
);
6351 while (read (fd
, buf
, auxv_size
) == auxv_size
6352 && (*phdr_memaddr
== 0 || *num_phdr
== 0))
6356 Elf64_auxv_t
*const aux
= (Elf64_auxv_t
*) buf
;
6358 switch (aux
->a_type
)
6361 *phdr_memaddr
= aux
->a_un
.a_val
;
6364 *num_phdr
= aux
->a_un
.a_val
;
6370 Elf32_auxv_t
*const aux
= (Elf32_auxv_t
*) buf
;
6372 switch (aux
->a_type
)
6375 *phdr_memaddr
= aux
->a_un
.a_val
;
6378 *num_phdr
= aux
->a_un
.a_val
;
6386 if (*phdr_memaddr
== 0 || *num_phdr
== 0)
6388 warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
6389 "phdr_memaddr = %ld, phdr_num = %d",
6390 (long) *phdr_memaddr
, *num_phdr
);
6397 /* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
6400 get_dynamic (const int pid
, const int is_elf64
)
6402 CORE_ADDR phdr_memaddr
, relocation
;
6404 unsigned char *phdr_buf
;
6405 const int phdr_size
= is_elf64
? sizeof (Elf64_Phdr
) : sizeof (Elf32_Phdr
);
6407 if (get_phdr_phnum_from_proc_auxv (pid
, is_elf64
, &phdr_memaddr
, &num_phdr
))
6410 gdb_assert (num_phdr
< 100); /* Basic sanity check. */
6411 phdr_buf
= (unsigned char *) alloca (num_phdr
* phdr_size
);
6413 if (linux_read_memory (phdr_memaddr
, phdr_buf
, num_phdr
* phdr_size
))
6416 /* Compute relocation: it is expected to be 0 for "regular" executables,
6417 non-zero for PIE ones. */
6419 for (i
= 0; relocation
== -1 && i
< num_phdr
; i
++)
6422 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6424 if (p
->p_type
== PT_PHDR
)
6425 relocation
= phdr_memaddr
- p
->p_vaddr
;
6429 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6431 if (p
->p_type
== PT_PHDR
)
6432 relocation
= phdr_memaddr
- p
->p_vaddr
;
6435 if (relocation
== -1)
6437 /* PT_PHDR is optional, but necessary for PIE in general. Fortunately
6438 any real world executables, including PIE executables, have always
6439 PT_PHDR present. PT_PHDR is not present in some shared libraries or
6440 in fpc (Free Pascal 2.4) binaries but neither of those have a need for
6441 or present DT_DEBUG anyway (fpc binaries are statically linked).
6443 Therefore if there exists DT_DEBUG there is always also PT_PHDR.
6445 GDB could find RELOCATION also from AT_ENTRY - e_entry. */
6450 for (i
= 0; i
< num_phdr
; i
++)
6454 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6456 if (p
->p_type
== PT_DYNAMIC
)
6457 return p
->p_vaddr
+ relocation
;
6461 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6463 if (p
->p_type
== PT_DYNAMIC
)
6464 return p
->p_vaddr
+ relocation
;
6471 /* Return &_r_debug in the inferior, or -1 if not present. Return value
6472 can be 0 if the inferior does not yet have the library list initialized.
6473 We look for DT_MIPS_RLD_MAP first. MIPS executables use this instead of
6474 DT_DEBUG, although they sometimes contain an unused DT_DEBUG entry too. */
6477 get_r_debug (const int pid
, const int is_elf64
)
6479 CORE_ADDR dynamic_memaddr
;
6480 const int dyn_size
= is_elf64
? sizeof (Elf64_Dyn
) : sizeof (Elf32_Dyn
);
6481 unsigned char buf
[sizeof (Elf64_Dyn
)]; /* The larger of the two. */
6484 dynamic_memaddr
= get_dynamic (pid
, is_elf64
);
6485 if (dynamic_memaddr
== 0)
6488 while (linux_read_memory (dynamic_memaddr
, buf
, dyn_size
) == 0)
6492 Elf64_Dyn
*const dyn
= (Elf64_Dyn
*) buf
;
6493 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
6497 unsigned char buf
[sizeof (Elf64_Xword
)];
6501 #ifdef DT_MIPS_RLD_MAP
6502 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
6504 if (linux_read_memory (dyn
->d_un
.d_val
,
6505 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6510 #endif /* DT_MIPS_RLD_MAP */
6511 #ifdef DT_MIPS_RLD_MAP_REL
6512 if (dyn
->d_tag
== DT_MIPS_RLD_MAP_REL
)
6514 if (linux_read_memory (dyn
->d_un
.d_val
+ dynamic_memaddr
,
6515 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6520 #endif /* DT_MIPS_RLD_MAP_REL */
6522 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
6523 map
= dyn
->d_un
.d_val
;
6525 if (dyn
->d_tag
== DT_NULL
)
6530 Elf32_Dyn
*const dyn
= (Elf32_Dyn
*) buf
;
6531 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
6535 unsigned char buf
[sizeof (Elf32_Word
)];
6539 #ifdef DT_MIPS_RLD_MAP
6540 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
6542 if (linux_read_memory (dyn
->d_un
.d_val
,
6543 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6548 #endif /* DT_MIPS_RLD_MAP */
6549 #ifdef DT_MIPS_RLD_MAP_REL
6550 if (dyn
->d_tag
== DT_MIPS_RLD_MAP_REL
)
6552 if (linux_read_memory (dyn
->d_un
.d_val
+ dynamic_memaddr
,
6553 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6558 #endif /* DT_MIPS_RLD_MAP_REL */
6560 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
6561 map
= dyn
->d_un
.d_val
;
6563 if (dyn
->d_tag
== DT_NULL
)
6567 dynamic_memaddr
+= dyn_size
;
6573 /* Read one pointer from MEMADDR in the inferior. */
6576 read_one_ptr (CORE_ADDR memaddr
, CORE_ADDR
*ptr
, int ptr_size
)
6580 /* Go through a union so this works on either big or little endian
6581 hosts, when the inferior's pointer size is smaller than the size
6582 of CORE_ADDR. It is assumed the inferior's endianness is the
6583 same of the superior's. */
6586 CORE_ADDR core_addr
;
6591 ret
= linux_read_memory (memaddr
, &addr
.uc
, ptr_size
);
6594 if (ptr_size
== sizeof (CORE_ADDR
))
6595 *ptr
= addr
.core_addr
;
6596 else if (ptr_size
== sizeof (unsigned int))
6599 gdb_assert_not_reached ("unhandled pointer size");
6604 struct link_map_offsets
6606 /* Offset and size of r_debug.r_version. */
6607 int r_version_offset
;
6609 /* Offset and size of r_debug.r_map. */
6612 /* Offset to l_addr field in struct link_map. */
6615 /* Offset to l_name field in struct link_map. */
6618 /* Offset to l_ld field in struct link_map. */
6621 /* Offset to l_next field in struct link_map. */
6624 /* Offset to l_prev field in struct link_map. */
6628 /* Construct qXfer:libraries-svr4:read reply. */
6631 linux_qxfer_libraries_svr4 (const char *annex
, unsigned char *readbuf
,
6632 unsigned const char *writebuf
,
6633 CORE_ADDR offset
, int len
)
6636 unsigned document_len
;
6637 struct process_info_private
*const priv
= current_process ()->priv
;
6638 char filename
[PATH_MAX
];
6641 static const struct link_map_offsets lmo_32bit_offsets
=
6643 0, /* r_version offset. */
6644 4, /* r_debug.r_map offset. */
6645 0, /* l_addr offset in link_map. */
6646 4, /* l_name offset in link_map. */
6647 8, /* l_ld offset in link_map. */
6648 12, /* l_next offset in link_map. */
6649 16 /* l_prev offset in link_map. */
6652 static const struct link_map_offsets lmo_64bit_offsets
=
6654 0, /* r_version offset. */
6655 8, /* r_debug.r_map offset. */
6656 0, /* l_addr offset in link_map. */
6657 8, /* l_name offset in link_map. */
6658 16, /* l_ld offset in link_map. */
6659 24, /* l_next offset in link_map. */
6660 32 /* l_prev offset in link_map. */
6662 const struct link_map_offsets
*lmo
;
6663 unsigned int machine
;
6665 CORE_ADDR lm_addr
= 0, lm_prev
= 0;
6666 int allocated
= 1024;
6668 CORE_ADDR l_name
, l_addr
, l_ld
, l_next
, l_prev
;
6669 int header_done
= 0;
6671 if (writebuf
!= NULL
)
6673 if (readbuf
== NULL
)
6676 pid
= lwpid_of (current_thread
);
6677 xsnprintf (filename
, sizeof filename
, "/proc/%d/exe", pid
);
6678 is_elf64
= elf_64_file_p (filename
, &machine
);
6679 lmo
= is_elf64
? &lmo_64bit_offsets
: &lmo_32bit_offsets
;
6680 ptr_size
= is_elf64
? 8 : 4;
6682 while (annex
[0] != '\0')
6688 sep
= strchr (annex
, '=');
6693 if (len
== 5 && startswith (annex
, "start"))
6695 else if (len
== 4 && startswith (annex
, "prev"))
6699 annex
= strchr (sep
, ';');
6706 annex
= decode_address_to_semicolon (addrp
, sep
+ 1);
6713 if (priv
->r_debug
== 0)
6714 priv
->r_debug
= get_r_debug (pid
, is_elf64
);
6716 /* We failed to find DT_DEBUG. Such situation will not change
6717 for this inferior - do not retry it. Report it to GDB as
6718 E01, see for the reasons at the GDB solib-svr4.c side. */
6719 if (priv
->r_debug
== (CORE_ADDR
) -1)
6722 if (priv
->r_debug
!= 0)
6724 if (linux_read_memory (priv
->r_debug
+ lmo
->r_version_offset
,
6725 (unsigned char *) &r_version
,
6726 sizeof (r_version
)) != 0
6729 warning ("unexpected r_debug version %d", r_version
);
6731 else if (read_one_ptr (priv
->r_debug
+ lmo
->r_map_offset
,
6732 &lm_addr
, ptr_size
) != 0)
6734 warning ("unable to read r_map from 0x%lx",
6735 (long) priv
->r_debug
+ lmo
->r_map_offset
);
6740 document
= (char *) xmalloc (allocated
);
6741 strcpy (document
, "<library-list-svr4 version=\"1.0\"");
6742 p
= document
+ strlen (document
);
6745 && read_one_ptr (lm_addr
+ lmo
->l_name_offset
,
6746 &l_name
, ptr_size
) == 0
6747 && read_one_ptr (lm_addr
+ lmo
->l_addr_offset
,
6748 &l_addr
, ptr_size
) == 0
6749 && read_one_ptr (lm_addr
+ lmo
->l_ld_offset
,
6750 &l_ld
, ptr_size
) == 0
6751 && read_one_ptr (lm_addr
+ lmo
->l_prev_offset
,
6752 &l_prev
, ptr_size
) == 0
6753 && read_one_ptr (lm_addr
+ lmo
->l_next_offset
,
6754 &l_next
, ptr_size
) == 0)
6756 unsigned char libname
[PATH_MAX
];
6758 if (lm_prev
!= l_prev
)
6760 warning ("Corrupted shared library list: 0x%lx != 0x%lx",
6761 (long) lm_prev
, (long) l_prev
);
6765 /* Ignore the first entry even if it has valid name as the first entry
6766 corresponds to the main executable. The first entry should not be
6767 skipped if the dynamic loader was loaded late by a static executable
6768 (see solib-svr4.c parameter ignore_first). But in such case the main
6769 executable does not have PT_DYNAMIC present and this function already
6770 exited above due to failed get_r_debug. */
6773 sprintf (p
, " main-lm=\"0x%lx\"", (unsigned long) lm_addr
);
6778 /* Not checking for error because reading may stop before
6779 we've got PATH_MAX worth of characters. */
6781 linux_read_memory (l_name
, libname
, sizeof (libname
) - 1);
6782 libname
[sizeof (libname
) - 1] = '\0';
6783 if (libname
[0] != '\0')
6785 /* 6x the size for xml_escape_text below. */
6786 size_t len
= 6 * strlen ((char *) libname
);
6791 /* Terminate `<library-list-svr4'. */
6796 while (allocated
< p
- document
+ len
+ 200)
6798 /* Expand to guarantee sufficient storage. */
6799 uintptr_t document_len
= p
- document
;
6801 document
= (char *) xrealloc (document
, 2 * allocated
);
6803 p
= document
+ document_len
;
6806 name
= xml_escape_text ((char *) libname
);
6807 p
+= sprintf (p
, "<library name=\"%s\" lm=\"0x%lx\" "
6808 "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
6809 name
, (unsigned long) lm_addr
,
6810 (unsigned long) l_addr
, (unsigned long) l_ld
);
6821 /* Empty list; terminate `<library-list-svr4'. */
6825 strcpy (p
, "</library-list-svr4>");
6827 document_len
= strlen (document
);
6828 if (offset
< document_len
)
6829 document_len
-= offset
;
6832 if (len
> document_len
)
6835 memcpy (readbuf
, document
+ offset
, len
);
6841 #ifdef HAVE_LINUX_BTRACE
6843 /* See to_disable_btrace target method. */
6846 linux_low_disable_btrace (struct btrace_target_info
*tinfo
)
6848 enum btrace_error err
;
6850 err
= linux_disable_btrace (tinfo
);
6851 return (err
== BTRACE_ERR_NONE
? 0 : -1);
6854 /* Encode an Intel(R) Processor Trace configuration. */
6857 linux_low_encode_pt_config (struct buffer
*buffer
,
6858 const struct btrace_data_pt_config
*config
)
6860 buffer_grow_str (buffer
, "<pt-config>\n");
6862 switch (config
->cpu
.vendor
)
6865 buffer_xml_printf (buffer
, "<cpu vendor=\"GenuineIntel\" family=\"%u\" "
6866 "model=\"%u\" stepping=\"%u\"/>\n",
6867 config
->cpu
.family
, config
->cpu
.model
,
6868 config
->cpu
.stepping
);
6875 buffer_grow_str (buffer
, "</pt-config>\n");
6878 /* Encode a raw buffer. */
6881 linux_low_encode_raw (struct buffer
*buffer
, const gdb_byte
*data
,
6887 /* We use hex encoding - see common/rsp-low.h. */
6888 buffer_grow_str (buffer
, "<raw>\n");
6894 elem
[0] = tohex ((*data
>> 4) & 0xf);
6895 elem
[1] = tohex (*data
++ & 0xf);
6897 buffer_grow (buffer
, elem
, 2);
6900 buffer_grow_str (buffer
, "</raw>\n");
6903 /* See to_read_btrace target method. */
6906 linux_low_read_btrace (struct btrace_target_info
*tinfo
, struct buffer
*buffer
,
6907 enum btrace_read_type type
)
6909 struct btrace_data btrace
;
6910 struct btrace_block
*block
;
6911 enum btrace_error err
;
6914 btrace_data_init (&btrace
);
6916 err
= linux_read_btrace (&btrace
, tinfo
, type
);
6917 if (err
!= BTRACE_ERR_NONE
)
6919 if (err
== BTRACE_ERR_OVERFLOW
)
6920 buffer_grow_str0 (buffer
, "E.Overflow.");
6922 buffer_grow_str0 (buffer
, "E.Generic Error.");
6927 switch (btrace
.format
)
6929 case BTRACE_FORMAT_NONE
:
6930 buffer_grow_str0 (buffer
, "E.No Trace.");
6933 case BTRACE_FORMAT_BTS
:
6934 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
6935 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
6938 VEC_iterate (btrace_block_s
, btrace
.variant
.bts
.blocks
, i
, block
);
6940 buffer_xml_printf (buffer
, "<block begin=\"0x%s\" end=\"0x%s\"/>\n",
6941 paddress (block
->begin
), paddress (block
->end
));
6943 buffer_grow_str0 (buffer
, "</btrace>\n");
6946 case BTRACE_FORMAT_PT
:
6947 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
6948 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
6949 buffer_grow_str (buffer
, "<pt>\n");
6951 linux_low_encode_pt_config (buffer
, &btrace
.variant
.pt
.config
);
6953 linux_low_encode_raw (buffer
, btrace
.variant
.pt
.data
,
6954 btrace
.variant
.pt
.size
);
6956 buffer_grow_str (buffer
, "</pt>\n");
6957 buffer_grow_str0 (buffer
, "</btrace>\n");
6961 buffer_grow_str0 (buffer
, "E.Unsupported Trace Format.");
6965 btrace_data_fini (&btrace
);
6969 btrace_data_fini (&btrace
);
6973 /* See to_btrace_conf target method. */
6976 linux_low_btrace_conf (const struct btrace_target_info
*tinfo
,
6977 struct buffer
*buffer
)
6979 const struct btrace_config
*conf
;
6981 buffer_grow_str (buffer
, "<!DOCTYPE btrace-conf SYSTEM \"btrace-conf.dtd\">\n");
6982 buffer_grow_str (buffer
, "<btrace-conf version=\"1.0\">\n");
6984 conf
= linux_btrace_conf (tinfo
);
6987 switch (conf
->format
)
6989 case BTRACE_FORMAT_NONE
:
6992 case BTRACE_FORMAT_BTS
:
6993 buffer_xml_printf (buffer
, "<bts");
6994 buffer_xml_printf (buffer
, " size=\"0x%x\"", conf
->bts
.size
);
6995 buffer_xml_printf (buffer
, " />\n");
6998 case BTRACE_FORMAT_PT
:
6999 buffer_xml_printf (buffer
, "<pt");
7000 buffer_xml_printf (buffer
, " size=\"0x%x\"", conf
->pt
.size
);
7001 buffer_xml_printf (buffer
, "/>\n");
7006 buffer_grow_str0 (buffer
, "</btrace-conf>\n");
7009 #endif /* HAVE_LINUX_BTRACE */
7011 /* See nat/linux-nat.h. */
7014 current_lwp_ptid (void)
7016 return ptid_of (current_thread
);
7019 /* Implementation of the target_ops method "breakpoint_kind_from_pc". */
7022 linux_breakpoint_kind_from_pc (CORE_ADDR
*pcptr
)
7024 if (the_low_target
.breakpoint_kind_from_pc
!= NULL
)
7025 return (*the_low_target
.breakpoint_kind_from_pc
) (pcptr
);
7027 return default_breakpoint_kind_from_pc (pcptr
);
7030 /* Implementation of the target_ops method "sw_breakpoint_from_kind". */
7032 static const gdb_byte
*
7033 linux_sw_breakpoint_from_kind (int kind
, int *size
)
7035 gdb_assert (the_low_target
.sw_breakpoint_from_kind
!= NULL
);
7037 return (*the_low_target
.sw_breakpoint_from_kind
) (kind
, size
);
7040 /* Implementation of the target_ops method
7041 "breakpoint_kind_from_current_state". */
7044 linux_breakpoint_kind_from_current_state (CORE_ADDR
*pcptr
)
7046 if (the_low_target
.breakpoint_kind_from_current_state
!= NULL
)
7047 return (*the_low_target
.breakpoint_kind_from_current_state
) (pcptr
);
7049 return linux_breakpoint_kind_from_pc (pcptr
);
7052 static struct target_ops linux_target_ops
= {
7053 linux_create_inferior
,
7063 linux_fetch_registers
,
7064 linux_store_registers
,
7065 linux_prepare_to_access_memory
,
7066 linux_done_accessing_memory
,
7069 linux_look_up_symbols
,
7070 linux_request_interrupt
,
7072 linux_supports_z_point_type
,
7075 linux_stopped_by_sw_breakpoint
,
7076 linux_supports_stopped_by_sw_breakpoint
,
7077 linux_stopped_by_hw_breakpoint
,
7078 linux_supports_stopped_by_hw_breakpoint
,
7079 linux_supports_hardware_single_step
,
7080 linux_stopped_by_watchpoint
,
7081 linux_stopped_data_address
,
7082 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
7083 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
7084 && defined(PT_TEXT_END_ADDR)
7089 #ifdef USE_THREAD_DB
7090 thread_db_get_tls_address
,
7095 hostio_last_error_from_errno
,
7098 linux_supports_non_stop
,
7100 linux_start_non_stop
,
7101 linux_supports_multi_process
,
7102 linux_supports_fork_events
,
7103 linux_supports_vfork_events
,
7104 linux_supports_exec_events
,
7105 linux_handle_new_gdb_connection
,
7106 #ifdef USE_THREAD_DB
7107 thread_db_handle_monitor_command
,
7111 linux_common_core_of_thread
,
7113 linux_process_qsupported
,
7114 linux_supports_tracepoints
,
7117 linux_thread_stopped
,
7121 linux_stabilize_threads
,
7122 linux_install_fast_tracepoint_jump_pad
,
7124 linux_supports_disable_randomization
,
7125 linux_get_min_fast_tracepoint_insn_len
,
7126 linux_qxfer_libraries_svr4
,
7127 linux_supports_agent
,
7128 #ifdef HAVE_LINUX_BTRACE
7129 linux_supports_btrace
,
7130 linux_enable_btrace
,
7131 linux_low_disable_btrace
,
7132 linux_low_read_btrace
,
7133 linux_low_btrace_conf
,
7141 linux_supports_range_stepping
,
7142 linux_proc_pid_to_exec_file
,
7143 linux_mntns_open_cloexec
,
7145 linux_mntns_readlink
,
7146 linux_breakpoint_kind_from_pc
,
7147 linux_sw_breakpoint_from_kind
,
7148 linux_proc_tid_get_name
,
7149 linux_breakpoint_kind_from_current_state
7153 linux_init_signals ()
7155 /* FIXME drow/2002-06-09: As above, we should check with LinuxThreads
7156 to find what the cancel signal actually is. */
7157 #ifndef __ANDROID__ /* Bionic doesn't use SIGRTMIN the way glibc does. */
7158 signal (__SIGRTMIN
+1, SIG_IGN
);
7162 #ifdef HAVE_LINUX_REGSETS
7164 initialize_regsets_info (struct regsets_info
*info
)
7166 for (info
->num_regsets
= 0;
7167 info
->regsets
[info
->num_regsets
].size
>= 0;
7168 info
->num_regsets
++)
7174 initialize_low (void)
7176 struct sigaction sigchld_action
;
7178 memset (&sigchld_action
, 0, sizeof (sigchld_action
));
7179 set_target_ops (&linux_target_ops
);
7181 linux_init_signals ();
7182 linux_ptrace_init_warnings ();
7184 sigchld_action
.sa_handler
= sigchld_handler
;
7185 sigemptyset (&sigchld_action
.sa_mask
);
7186 sigchld_action
.sa_flags
= SA_RESTART
;
7187 sigaction (SIGCHLD
, &sigchld_action
, NULL
);
7189 initialize_low_arch ();
7191 linux_check_ptrace_features ();