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. */
275 can_hardware_single_step (void)
277 if (the_low_target
.supports_hardware_single_step
!= NULL
)
278 return the_low_target
.supports_hardware_single_step ();
283 /* True if the low target can software single-step. Such targets
284 implement the BREAKPOINT_REINSERT_ADDR callback. */
287 can_software_single_step (void)
289 return (the_low_target
.breakpoint_reinsert_addr
!= NULL
);
292 /* True if the low target supports memory breakpoints. If so, we'll
293 have a GET_PC implementation. */
296 supports_breakpoints (void)
298 return (the_low_target
.get_pc
!= NULL
);
301 /* Returns true if this target can support fast tracepoints. This
302 does not mean that the in-process agent has been loaded in the
306 supports_fast_tracepoints (void)
308 return the_low_target
.install_fast_tracepoint_jump_pad
!= NULL
;
311 /* True if LWP is stopped in its stepping range. */
314 lwp_in_step_range (struct lwp_info
*lwp
)
316 CORE_ADDR pc
= lwp
->stop_pc
;
318 return (pc
>= lwp
->step_range_start
&& pc
< lwp
->step_range_end
);
321 struct pending_signals
325 struct pending_signals
*prev
;
328 /* The read/write ends of the pipe registered as waitable file in the
330 static int linux_event_pipe
[2] = { -1, -1 };
332 /* True if we're currently in async mode. */
333 #define target_is_async_p() (linux_event_pipe[0] != -1)
335 static void send_sigstop (struct lwp_info
*lwp
);
336 static void wait_for_sigstop (void);
338 /* Return non-zero if HEADER is a 64-bit ELF file. */
341 elf_64_header_p (const Elf64_Ehdr
*header
, unsigned int *machine
)
343 if (header
->e_ident
[EI_MAG0
] == ELFMAG0
344 && header
->e_ident
[EI_MAG1
] == ELFMAG1
345 && header
->e_ident
[EI_MAG2
] == ELFMAG2
346 && header
->e_ident
[EI_MAG3
] == ELFMAG3
)
348 *machine
= header
->e_machine
;
349 return header
->e_ident
[EI_CLASS
] == ELFCLASS64
;
356 /* Return non-zero if FILE is a 64-bit ELF file,
357 zero if the file is not a 64-bit ELF file,
358 and -1 if the file is not accessible or doesn't exist. */
361 elf_64_file_p (const char *file
, unsigned int *machine
)
366 fd
= open (file
, O_RDONLY
);
370 if (read (fd
, &header
, sizeof (header
)) != sizeof (header
))
377 return elf_64_header_p (&header
, machine
);
380 /* Accepts an integer PID; Returns true if the executable PID is
381 running is a 64-bit ELF file.. */
384 linux_pid_exe_is_elf_64_file (int pid
, unsigned int *machine
)
388 sprintf (file
, "/proc/%d/exe", pid
);
389 return elf_64_file_p (file
, machine
);
393 delete_lwp (struct lwp_info
*lwp
)
395 struct thread_info
*thr
= get_lwp_thread (lwp
);
398 debug_printf ("deleting %ld\n", lwpid_of (thr
));
401 free (lwp
->arch_private
);
405 /* Add a process to the common process list, and set its private
408 static struct process_info
*
409 linux_add_process (int pid
, int attached
)
411 struct process_info
*proc
;
413 proc
= add_process (pid
, attached
);
414 proc
->priv
= XCNEW (struct process_info_private
);
416 if (the_low_target
.new_process
!= NULL
)
417 proc
->priv
->arch_private
= the_low_target
.new_process ();
422 static CORE_ADDR
get_pc (struct lwp_info
*lwp
);
424 /* Implement the arch_setup target_ops method. */
427 linux_arch_setup (void)
429 the_low_target
.arch_setup ();
432 /* Call the target arch_setup function on THREAD. */
435 linux_arch_setup_thread (struct thread_info
*thread
)
437 struct thread_info
*saved_thread
;
439 saved_thread
= current_thread
;
440 current_thread
= thread
;
444 current_thread
= saved_thread
;
447 /* Handle a GNU/Linux extended wait response. If we see a clone,
448 fork, or vfork event, we need to add the new LWP to our list
449 (and return 0 so as not to report the trap to higher layers).
450 If we see an exec event, we will modify ORIG_EVENT_LWP to point
451 to a new LWP representing the new program. */
454 handle_extended_wait (struct lwp_info
**orig_event_lwp
, int wstat
)
456 struct lwp_info
*event_lwp
= *orig_event_lwp
;
457 int event
= linux_ptrace_get_extended_event (wstat
);
458 struct thread_info
*event_thr
= get_lwp_thread (event_lwp
);
459 struct lwp_info
*new_lwp
;
461 gdb_assert (event_lwp
->waitstatus
.kind
== TARGET_WAITKIND_IGNORE
);
463 if ((event
== PTRACE_EVENT_FORK
) || (event
== PTRACE_EVENT_VFORK
)
464 || (event
== PTRACE_EVENT_CLONE
))
467 unsigned long new_pid
;
470 /* Get the pid of the new lwp. */
471 ptrace (PTRACE_GETEVENTMSG
, lwpid_of (event_thr
), (PTRACE_TYPE_ARG3
) 0,
474 /* If we haven't already seen the new PID stop, wait for it now. */
475 if (!pull_pid_from_list (&stopped_pids
, new_pid
, &status
))
477 /* The new child has a pending SIGSTOP. We can't affect it until it
478 hits the SIGSTOP, but we're already attached. */
480 ret
= my_waitpid (new_pid
, &status
, __WALL
);
483 perror_with_name ("waiting for new child");
484 else if (ret
!= new_pid
)
485 warning ("wait returned unexpected PID %d", ret
);
486 else if (!WIFSTOPPED (status
))
487 warning ("wait returned unexpected status 0x%x", status
);
490 if (event
== PTRACE_EVENT_FORK
|| event
== PTRACE_EVENT_VFORK
)
492 struct process_info
*parent_proc
;
493 struct process_info
*child_proc
;
494 struct lwp_info
*child_lwp
;
495 struct thread_info
*child_thr
;
496 struct target_desc
*tdesc
;
498 ptid
= ptid_build (new_pid
, new_pid
, 0);
502 debug_printf ("HEW: Got fork event from LWP %ld, "
504 ptid_get_lwp (ptid_of (event_thr
)),
505 ptid_get_pid (ptid
));
508 /* Add the new process to the tables and clone the breakpoint
509 lists of the parent. We need to do this even if the new process
510 will be detached, since we will need the process object and the
511 breakpoints to remove any breakpoints from memory when we
512 detach, and the client side will access registers. */
513 child_proc
= linux_add_process (new_pid
, 0);
514 gdb_assert (child_proc
!= NULL
);
515 child_lwp
= add_lwp (ptid
);
516 gdb_assert (child_lwp
!= NULL
);
517 child_lwp
->stopped
= 1;
518 child_lwp
->must_set_ptrace_flags
= 1;
519 child_lwp
->status_pending_p
= 0;
520 child_thr
= get_lwp_thread (child_lwp
);
521 child_thr
->last_resume_kind
= resume_stop
;
522 child_thr
->last_status
.kind
= TARGET_WAITKIND_STOPPED
;
524 /* If we're suspending all threads, leave this one suspended
526 if (stopping_threads
== STOPPING_AND_SUSPENDING_THREADS
)
529 debug_printf ("HEW: leaving child suspended\n");
530 child_lwp
->suspended
= 1;
533 parent_proc
= get_thread_process (event_thr
);
534 child_proc
->attached
= parent_proc
->attached
;
535 clone_all_breakpoints (&child_proc
->breakpoints
,
536 &child_proc
->raw_breakpoints
,
537 parent_proc
->breakpoints
);
539 tdesc
= XNEW (struct target_desc
);
540 copy_target_description (tdesc
, parent_proc
->tdesc
);
541 child_proc
->tdesc
= tdesc
;
543 /* Clone arch-specific process data. */
544 if (the_low_target
.new_fork
!= NULL
)
545 the_low_target
.new_fork (parent_proc
, child_proc
);
547 /* Save fork info in the parent thread. */
548 if (event
== PTRACE_EVENT_FORK
)
549 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_FORKED
;
550 else if (event
== PTRACE_EVENT_VFORK
)
551 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_VFORKED
;
553 event_lwp
->waitstatus
.value
.related_pid
= ptid
;
555 /* The status_pending field contains bits denoting the
556 extended event, so when the pending event is handled,
557 the handler will look at lwp->waitstatus. */
558 event_lwp
->status_pending_p
= 1;
559 event_lwp
->status_pending
= wstat
;
561 /* Report the event. */
566 debug_printf ("HEW: Got clone event "
567 "from LWP %ld, new child is LWP %ld\n",
568 lwpid_of (event_thr
), new_pid
);
570 ptid
= ptid_build (pid_of (event_thr
), new_pid
, 0);
571 new_lwp
= add_lwp (ptid
);
573 /* Either we're going to immediately resume the new thread
574 or leave it stopped. linux_resume_one_lwp is a nop if it
575 thinks the thread is currently running, so set this first
576 before calling linux_resume_one_lwp. */
577 new_lwp
->stopped
= 1;
579 /* If we're suspending all threads, leave this one suspended
581 if (stopping_threads
== STOPPING_AND_SUSPENDING_THREADS
)
582 new_lwp
->suspended
= 1;
584 /* Normally we will get the pending SIGSTOP. But in some cases
585 we might get another signal delivered to the group first.
586 If we do get another signal, be sure not to lose it. */
587 if (WSTOPSIG (status
) != SIGSTOP
)
589 new_lwp
->stop_expected
= 1;
590 new_lwp
->status_pending_p
= 1;
591 new_lwp
->status_pending
= status
;
593 else if (report_thread_events
)
595 new_lwp
->waitstatus
.kind
= TARGET_WAITKIND_THREAD_CREATED
;
596 new_lwp
->status_pending_p
= 1;
597 new_lwp
->status_pending
= status
;
600 /* Don't report the event. */
603 else if (event
== PTRACE_EVENT_VFORK_DONE
)
605 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_VFORK_DONE
;
607 /* Report the event. */
610 else if (event
== PTRACE_EVENT_EXEC
&& report_exec_events
)
612 struct process_info
*proc
;
618 debug_printf ("HEW: Got exec event from LWP %ld\n",
619 lwpid_of (event_thr
));
622 /* Get the event ptid. */
623 event_ptid
= ptid_of (event_thr
);
624 event_pid
= ptid_get_pid (event_ptid
);
626 /* Delete the execing process and all its threads. */
627 proc
= get_thread_process (event_thr
);
629 current_thread
= NULL
;
631 /* Create a new process/lwp/thread. */
632 proc
= linux_add_process (event_pid
, 0);
633 event_lwp
= add_lwp (event_ptid
);
634 event_thr
= get_lwp_thread (event_lwp
);
635 gdb_assert (current_thread
== event_thr
);
636 linux_arch_setup_thread (event_thr
);
638 /* Set the event status. */
639 event_lwp
->waitstatus
.kind
= TARGET_WAITKIND_EXECD
;
640 event_lwp
->waitstatus
.value
.execd_pathname
641 = xstrdup (linux_proc_pid_to_exec_file (lwpid_of (event_thr
)));
643 /* Mark the exec status as pending. */
644 event_lwp
->stopped
= 1;
645 event_lwp
->status_pending_p
= 1;
646 event_lwp
->status_pending
= wstat
;
647 event_thr
->last_resume_kind
= resume_continue
;
648 event_thr
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
650 /* Report the event. */
651 *orig_event_lwp
= event_lwp
;
655 internal_error (__FILE__
, __LINE__
, _("unknown ptrace event %d"), event
);
658 /* Return the PC as read from the regcache of LWP, without any
662 get_pc (struct lwp_info
*lwp
)
664 struct thread_info
*saved_thread
;
665 struct regcache
*regcache
;
668 if (the_low_target
.get_pc
== NULL
)
671 saved_thread
= current_thread
;
672 current_thread
= get_lwp_thread (lwp
);
674 regcache
= get_thread_regcache (current_thread
, 1);
675 pc
= (*the_low_target
.get_pc
) (regcache
);
678 debug_printf ("pc is 0x%lx\n", (long) pc
);
680 current_thread
= saved_thread
;
684 /* This function should only be called if LWP got a SIGTRAP.
685 The SIGTRAP could mean several things.
687 On i386, where decr_pc_after_break is non-zero:
689 If we were single-stepping this process using PTRACE_SINGLESTEP, we
690 will get only the one SIGTRAP. The value of $eip will be the next
691 instruction. If the instruction we stepped over was a breakpoint,
692 we need to decrement the PC.
694 If we continue the process using PTRACE_CONT, we will get a
695 SIGTRAP when we hit a breakpoint. The value of $eip will be
696 the instruction after the breakpoint (i.e. needs to be
697 decremented). If we report the SIGTRAP to GDB, we must also
698 report the undecremented PC. If the breakpoint is removed, we
699 must resume at the decremented PC.
701 On a non-decr_pc_after_break machine with hardware or kernel
704 If we either single-step a breakpoint instruction, or continue and
705 hit a breakpoint instruction, our PC will point at the breakpoint
709 check_stopped_by_breakpoint (struct lwp_info
*lwp
)
712 CORE_ADDR sw_breakpoint_pc
;
713 struct thread_info
*saved_thread
;
714 #if USE_SIGTRAP_SIGINFO
718 if (the_low_target
.get_pc
== NULL
)
722 sw_breakpoint_pc
= pc
- the_low_target
.decr_pc_after_break
;
724 /* breakpoint_at reads from the current thread. */
725 saved_thread
= current_thread
;
726 current_thread
= get_lwp_thread (lwp
);
728 #if USE_SIGTRAP_SIGINFO
729 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
730 (PTRACE_TYPE_ARG3
) 0, &siginfo
) == 0)
732 if (siginfo
.si_signo
== SIGTRAP
)
734 if (GDB_ARCH_IS_TRAP_BRKPT (siginfo
.si_code
))
738 struct thread_info
*thr
= get_lwp_thread (lwp
);
740 debug_printf ("CSBB: %s stopped by software breakpoint\n",
741 target_pid_to_str (ptid_of (thr
)));
744 /* Back up the PC if necessary. */
745 if (pc
!= sw_breakpoint_pc
)
747 struct regcache
*regcache
748 = get_thread_regcache (current_thread
, 1);
749 (*the_low_target
.set_pc
) (regcache
, sw_breakpoint_pc
);
752 lwp
->stop_pc
= sw_breakpoint_pc
;
753 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
754 current_thread
= saved_thread
;
757 else if (siginfo
.si_code
== TRAP_HWBKPT
)
761 struct thread_info
*thr
= get_lwp_thread (lwp
);
763 debug_printf ("CSBB: %s stopped by hardware "
764 "breakpoint/watchpoint\n",
765 target_pid_to_str (ptid_of (thr
)));
769 lwp
->stop_reason
= TARGET_STOPPED_BY_HW_BREAKPOINT
;
770 current_thread
= saved_thread
;
773 else if (siginfo
.si_code
== TRAP_TRACE
)
777 struct thread_info
*thr
= get_lwp_thread (lwp
);
779 debug_printf ("CSBB: %s stopped by trace\n",
780 target_pid_to_str (ptid_of (thr
)));
783 lwp
->stop_reason
= TARGET_STOPPED_BY_SINGLE_STEP
;
788 /* We may have just stepped a breakpoint instruction. E.g., in
789 non-stop mode, GDB first tells the thread A to step a range, and
790 then the user inserts a breakpoint inside the range. In that
791 case we need to report the breakpoint PC. */
792 if ((!lwp
->stepping
|| lwp
->stop_pc
== sw_breakpoint_pc
)
793 && (*the_low_target
.breakpoint_at
) (sw_breakpoint_pc
))
797 struct thread_info
*thr
= get_lwp_thread (lwp
);
799 debug_printf ("CSBB: %s stopped by software breakpoint\n",
800 target_pid_to_str (ptid_of (thr
)));
803 /* Back up the PC if necessary. */
804 if (pc
!= sw_breakpoint_pc
)
806 struct regcache
*regcache
807 = get_thread_regcache (current_thread
, 1);
808 (*the_low_target
.set_pc
) (regcache
, sw_breakpoint_pc
);
811 lwp
->stop_pc
= sw_breakpoint_pc
;
812 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
813 current_thread
= saved_thread
;
817 if (hardware_breakpoint_inserted_here (pc
))
821 struct thread_info
*thr
= get_lwp_thread (lwp
);
823 debug_printf ("CSBB: %s stopped by hardware breakpoint\n",
824 target_pid_to_str (ptid_of (thr
)));
828 lwp
->stop_reason
= TARGET_STOPPED_BY_HW_BREAKPOINT
;
829 current_thread
= saved_thread
;
834 current_thread
= saved_thread
;
838 static struct lwp_info
*
839 add_lwp (ptid_t ptid
)
841 struct lwp_info
*lwp
;
843 lwp
= XCNEW (struct lwp_info
);
845 lwp
->waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
847 if (the_low_target
.new_thread
!= NULL
)
848 the_low_target
.new_thread (lwp
);
850 lwp
->thread
= add_thread (ptid
, lwp
);
855 /* Start an inferior process and returns its pid.
856 ALLARGS is a vector of program-name and args. */
859 linux_create_inferior (char *program
, char **allargs
)
861 struct lwp_info
*new_lwp
;
864 struct cleanup
*restore_personality
865 = maybe_disable_address_space_randomization (disable_randomization
);
867 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
873 perror_with_name ("fork");
878 ptrace (PTRACE_TRACEME
, 0, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
880 #ifndef __ANDROID__ /* Bionic doesn't use SIGRTMIN the way glibc does. */
881 signal (__SIGRTMIN
+ 1, SIG_DFL
);
886 /* If gdbserver is connected to gdb via stdio, redirect the inferior's
887 stdout to stderr so that inferior i/o doesn't corrupt the connection.
888 Also, redirect stdin to /dev/null. */
889 if (remote_connection_is_stdio ())
892 open ("/dev/null", O_RDONLY
);
894 if (write (2, "stdin/stdout redirected\n",
895 sizeof ("stdin/stdout redirected\n") - 1) < 0)
897 /* Errors ignored. */;
901 execv (program
, allargs
);
903 execvp (program
, allargs
);
905 fprintf (stderr
, "Cannot exec %s: %s.\n", program
,
911 do_cleanups (restore_personality
);
913 linux_add_process (pid
, 0);
915 ptid
= ptid_build (pid
, pid
, 0);
916 new_lwp
= add_lwp (ptid
);
917 new_lwp
->must_set_ptrace_flags
= 1;
922 /* Attach to an inferior process. Returns 0 on success, ERRNO on
926 linux_attach_lwp (ptid_t ptid
)
928 struct lwp_info
*new_lwp
;
929 int lwpid
= ptid_get_lwp (ptid
);
931 if (ptrace (PTRACE_ATTACH
, lwpid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0)
935 new_lwp
= add_lwp (ptid
);
937 /* We need to wait for SIGSTOP before being able to make the next
938 ptrace call on this LWP. */
939 new_lwp
->must_set_ptrace_flags
= 1;
941 if (linux_proc_pid_is_stopped (lwpid
))
944 debug_printf ("Attached to a stopped process\n");
946 /* The process is definitely stopped. It is in a job control
947 stop, unless the kernel predates the TASK_STOPPED /
948 TASK_TRACED distinction, in which case it might be in a
949 ptrace stop. Make sure it is in a ptrace stop; from there we
950 can kill it, signal it, et cetera.
952 First make sure there is a pending SIGSTOP. Since we are
953 already attached, the process can not transition from stopped
954 to running without a PTRACE_CONT; so we know this signal will
955 go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
956 probably already in the queue (unless this kernel is old
957 enough to use TASK_STOPPED for ptrace stops); but since
958 SIGSTOP is not an RT signal, it can only be queued once. */
959 kill_lwp (lwpid
, SIGSTOP
);
961 /* Finally, resume the stopped process. This will deliver the
962 SIGSTOP (or a higher priority signal, just like normal
963 PTRACE_ATTACH), which we'll catch later on. */
964 ptrace (PTRACE_CONT
, lwpid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
967 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
970 There are several cases to consider here:
972 1) gdbserver has already attached to the process and is being notified
973 of a new thread that is being created.
974 In this case we should ignore that SIGSTOP and resume the
975 process. This is handled below by setting stop_expected = 1,
976 and the fact that add_thread sets last_resume_kind ==
979 2) This is the first thread (the process thread), and we're attaching
980 to it via attach_inferior.
981 In this case we want the process thread to stop.
982 This is handled by having linux_attach set last_resume_kind ==
983 resume_stop after we return.
985 If the pid we are attaching to is also the tgid, we attach to and
986 stop all the existing threads. Otherwise, we attach to pid and
987 ignore any other threads in the same group as this pid.
989 3) GDB is connecting to gdbserver and is requesting an enumeration of all
991 In this case we want the thread to stop.
992 FIXME: This case is currently not properly handled.
993 We should wait for the SIGSTOP but don't. Things work apparently
994 because enough time passes between when we ptrace (ATTACH) and when
995 gdb makes the next ptrace call on the thread.
997 On the other hand, if we are currently trying to stop all threads, we
998 should treat the new thread as if we had sent it a SIGSTOP. This works
999 because we are guaranteed that the add_lwp call above added us to the
1000 end of the list, and so the new thread has not yet reached
1001 wait_for_sigstop (but will). */
1002 new_lwp
->stop_expected
= 1;
1007 /* Callback for linux_proc_attach_tgid_threads. Attach to PTID if not
1008 already attached. Returns true if a new LWP is found, false
1012 attach_proc_task_lwp_callback (ptid_t ptid
)
1014 /* Is this a new thread? */
1015 if (find_thread_ptid (ptid
) == NULL
)
1017 int lwpid
= ptid_get_lwp (ptid
);
1021 debug_printf ("Found new lwp %d\n", lwpid
);
1023 err
= linux_attach_lwp (ptid
);
1025 /* Be quiet if we simply raced with the thread exiting. EPERM
1026 is returned if the thread's task still exists, and is marked
1027 as exited or zombie, as well as other conditions, so in that
1028 case, confirm the status in /proc/PID/status. */
1030 || (err
== EPERM
&& linux_proc_pid_is_gone (lwpid
)))
1034 debug_printf ("Cannot attach to lwp %d: "
1035 "thread is gone (%d: %s)\n",
1036 lwpid
, err
, strerror (err
));
1041 warning (_("Cannot attach to lwp %d: %s"),
1043 linux_ptrace_attach_fail_reason_string (ptid
, err
));
1051 static void async_file_mark (void);
1053 /* Attach to PID. If PID is the tgid, attach to it and all
1057 linux_attach (unsigned long pid
)
1059 struct process_info
*proc
;
1060 struct thread_info
*initial_thread
;
1061 ptid_t ptid
= ptid_build (pid
, pid
, 0);
1064 /* Attach to PID. We will check for other threads
1066 err
= linux_attach_lwp (ptid
);
1068 error ("Cannot attach to process %ld: %s",
1069 pid
, linux_ptrace_attach_fail_reason_string (ptid
, err
));
1071 proc
= linux_add_process (pid
, 1);
1073 /* Don't ignore the initial SIGSTOP if we just attached to this
1074 process. It will be collected by wait shortly. */
1075 initial_thread
= find_thread_ptid (ptid_build (pid
, pid
, 0));
1076 initial_thread
->last_resume_kind
= resume_stop
;
1078 /* We must attach to every LWP. If /proc is mounted, use that to
1079 find them now. On the one hand, the inferior may be using raw
1080 clone instead of using pthreads. On the other hand, even if it
1081 is using pthreads, GDB may not be connected yet (thread_db needs
1082 to do symbol lookups, through qSymbol). Also, thread_db walks
1083 structures in the inferior's address space to find the list of
1084 threads/LWPs, and those structures may well be corrupted. Note
1085 that once thread_db is loaded, we'll still use it to list threads
1086 and associate pthread info with each LWP. */
1087 linux_proc_attach_tgid_threads (pid
, attach_proc_task_lwp_callback
);
1089 /* GDB will shortly read the xml target description for this
1090 process, to figure out the process' architecture. But the target
1091 description is only filled in when the first process/thread in
1092 the thread group reports its initial PTRACE_ATTACH SIGSTOP. Do
1093 that now, otherwise, if GDB is fast enough, it could read the
1094 target description _before_ that initial stop. */
1097 struct lwp_info
*lwp
;
1099 ptid_t pid_ptid
= pid_to_ptid (pid
);
1101 lwpid
= linux_wait_for_event_filtered (pid_ptid
, pid_ptid
,
1103 gdb_assert (lwpid
> 0);
1105 lwp
= find_lwp_pid (pid_to_ptid (lwpid
));
1107 if (!WIFSTOPPED (wstat
) || WSTOPSIG (wstat
) != SIGSTOP
)
1109 lwp
->status_pending_p
= 1;
1110 lwp
->status_pending
= wstat
;
1113 initial_thread
->last_resume_kind
= resume_continue
;
1117 gdb_assert (proc
->tdesc
!= NULL
);
1130 second_thread_of_pid_p (struct inferior_list_entry
*entry
, void *args
)
1132 struct counter
*counter
= (struct counter
*) args
;
1134 if (ptid_get_pid (entry
->id
) == counter
->pid
)
1136 if (++counter
->count
> 1)
1144 last_thread_of_process_p (int pid
)
1146 struct counter counter
= { pid
, 0 };
1148 return (find_inferior (&all_threads
,
1149 second_thread_of_pid_p
, &counter
) == NULL
);
1155 linux_kill_one_lwp (struct lwp_info
*lwp
)
1157 struct thread_info
*thr
= get_lwp_thread (lwp
);
1158 int pid
= lwpid_of (thr
);
1160 /* PTRACE_KILL is unreliable. After stepping into a signal handler,
1161 there is no signal context, and ptrace(PTRACE_KILL) (or
1162 ptrace(PTRACE_CONT, SIGKILL), pretty much the same) acts like
1163 ptrace(CONT, pid, 0,0) and just resumes the tracee. A better
1164 alternative is to kill with SIGKILL. We only need one SIGKILL
1165 per process, not one for each thread. But since we still support
1166 linuxthreads, and we also support debugging programs using raw
1167 clone without CLONE_THREAD, we send one for each thread. For
1168 years, we used PTRACE_KILL only, so we're being a bit paranoid
1169 about some old kernels where PTRACE_KILL might work better
1170 (dubious if there are any such, but that's why it's paranoia), so
1171 we try SIGKILL first, PTRACE_KILL second, and so we're fine
1175 kill_lwp (pid
, SIGKILL
);
1178 int save_errno
= errno
;
1180 debug_printf ("LKL: kill_lwp (SIGKILL) %s, 0, 0 (%s)\n",
1181 target_pid_to_str (ptid_of (thr
)),
1182 save_errno
? strerror (save_errno
) : "OK");
1186 ptrace (PTRACE_KILL
, pid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
1189 int save_errno
= errno
;
1191 debug_printf ("LKL: PTRACE_KILL %s, 0, 0 (%s)\n",
1192 target_pid_to_str (ptid_of (thr
)),
1193 save_errno
? strerror (save_errno
) : "OK");
1197 /* Kill LWP and wait for it to die. */
1200 kill_wait_lwp (struct lwp_info
*lwp
)
1202 struct thread_info
*thr
= get_lwp_thread (lwp
);
1203 int pid
= ptid_get_pid (ptid_of (thr
));
1204 int lwpid
= ptid_get_lwp (ptid_of (thr
));
1209 debug_printf ("kwl: killing lwp %d, for pid: %d\n", lwpid
, pid
);
1213 linux_kill_one_lwp (lwp
);
1215 /* Make sure it died. Notes:
1217 - The loop is most likely unnecessary.
1219 - We don't use linux_wait_for_event as that could delete lwps
1220 while we're iterating over them. We're not interested in
1221 any pending status at this point, only in making sure all
1222 wait status on the kernel side are collected until the
1225 - We don't use __WALL here as the __WALL emulation relies on
1226 SIGCHLD, and killing a stopped process doesn't generate
1227 one, nor an exit status.
1229 res
= my_waitpid (lwpid
, &wstat
, 0);
1230 if (res
== -1 && errno
== ECHILD
)
1231 res
= my_waitpid (lwpid
, &wstat
, __WCLONE
);
1232 } while (res
> 0 && WIFSTOPPED (wstat
));
1234 /* Even if it was stopped, the child may have already disappeared.
1235 E.g., if it was killed by SIGKILL. */
1236 if (res
< 0 && errno
!= ECHILD
)
1237 perror_with_name ("kill_wait_lwp");
1240 /* Callback for `find_inferior'. Kills an lwp of a given process,
1241 except the leader. */
1244 kill_one_lwp_callback (struct inferior_list_entry
*entry
, void *args
)
1246 struct thread_info
*thread
= (struct thread_info
*) entry
;
1247 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1248 int pid
= * (int *) args
;
1250 if (ptid_get_pid (entry
->id
) != pid
)
1253 /* We avoid killing the first thread here, because of a Linux kernel (at
1254 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
1255 the children get a chance to be reaped, it will remain a zombie
1258 if (lwpid_of (thread
) == pid
)
1261 debug_printf ("lkop: is last of process %s\n",
1262 target_pid_to_str (entry
->id
));
1266 kill_wait_lwp (lwp
);
1271 linux_kill (int pid
)
1273 struct process_info
*process
;
1274 struct lwp_info
*lwp
;
1276 process
= find_process_pid (pid
);
1277 if (process
== NULL
)
1280 /* If we're killing a running inferior, make sure it is stopped
1281 first, as PTRACE_KILL will not work otherwise. */
1282 stop_all_lwps (0, NULL
);
1284 find_inferior (&all_threads
, kill_one_lwp_callback
, &pid
);
1286 /* See the comment in linux_kill_one_lwp. We did not kill the first
1287 thread in the list, so do so now. */
1288 lwp
= find_lwp_pid (pid_to_ptid (pid
));
1293 debug_printf ("lk_1: cannot find lwp for pid: %d\n",
1297 kill_wait_lwp (lwp
);
1299 the_target
->mourn (process
);
1301 /* Since we presently can only stop all lwps of all processes, we
1302 need to unstop lwps of other processes. */
1303 unstop_all_lwps (0, NULL
);
1307 /* Get pending signal of THREAD, for detaching purposes. This is the
1308 signal the thread last stopped for, which we need to deliver to the
1309 thread when detaching, otherwise, it'd be suppressed/lost. */
1312 get_detach_signal (struct thread_info
*thread
)
1314 enum gdb_signal signo
= GDB_SIGNAL_0
;
1316 struct lwp_info
*lp
= get_thread_lwp (thread
);
1318 if (lp
->status_pending_p
)
1319 status
= lp
->status_pending
;
1322 /* If the thread had been suspended by gdbserver, and it stopped
1323 cleanly, then it'll have stopped with SIGSTOP. But we don't
1324 want to deliver that SIGSTOP. */
1325 if (thread
->last_status
.kind
!= TARGET_WAITKIND_STOPPED
1326 || thread
->last_status
.value
.sig
== GDB_SIGNAL_0
)
1329 /* Otherwise, we may need to deliver the signal we
1331 status
= lp
->last_status
;
1334 if (!WIFSTOPPED (status
))
1337 debug_printf ("GPS: lwp %s hasn't stopped: no pending signal\n",
1338 target_pid_to_str (ptid_of (thread
)));
1342 /* Extended wait statuses aren't real SIGTRAPs. */
1343 if (WSTOPSIG (status
) == SIGTRAP
&& linux_is_extended_waitstatus (status
))
1346 debug_printf ("GPS: lwp %s had stopped with extended "
1347 "status: no pending signal\n",
1348 target_pid_to_str (ptid_of (thread
)));
1352 signo
= gdb_signal_from_host (WSTOPSIG (status
));
1354 if (program_signals_p
&& !program_signals
[signo
])
1357 debug_printf ("GPS: lwp %s had signal %s, but it is in nopass state\n",
1358 target_pid_to_str (ptid_of (thread
)),
1359 gdb_signal_to_string (signo
));
1362 else if (!program_signals_p
1363 /* If we have no way to know which signals GDB does not
1364 want to have passed to the program, assume
1365 SIGTRAP/SIGINT, which is GDB's default. */
1366 && (signo
== GDB_SIGNAL_TRAP
|| signo
== GDB_SIGNAL_INT
))
1369 debug_printf ("GPS: lwp %s had signal %s, "
1370 "but we don't know if we should pass it. "
1371 "Default to not.\n",
1372 target_pid_to_str (ptid_of (thread
)),
1373 gdb_signal_to_string (signo
));
1379 debug_printf ("GPS: lwp %s has pending signal %s: delivering it.\n",
1380 target_pid_to_str (ptid_of (thread
)),
1381 gdb_signal_to_string (signo
));
1383 return WSTOPSIG (status
);
1388 linux_detach_one_lwp (struct inferior_list_entry
*entry
, void *args
)
1390 struct thread_info
*thread
= (struct thread_info
*) entry
;
1391 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1392 int pid
= * (int *) args
;
1395 if (ptid_get_pid (entry
->id
) != pid
)
1398 /* If there is a pending SIGSTOP, get rid of it. */
1399 if (lwp
->stop_expected
)
1402 debug_printf ("Sending SIGCONT to %s\n",
1403 target_pid_to_str (ptid_of (thread
)));
1405 kill_lwp (lwpid_of (thread
), SIGCONT
);
1406 lwp
->stop_expected
= 0;
1409 /* Flush any pending changes to the process's registers. */
1410 regcache_invalidate_thread (thread
);
1412 /* Pass on any pending signal for this thread. */
1413 sig
= get_detach_signal (thread
);
1415 /* Finally, let it resume. */
1416 if (the_low_target
.prepare_to_resume
!= NULL
)
1417 the_low_target
.prepare_to_resume (lwp
);
1418 if (ptrace (PTRACE_DETACH
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
1419 (PTRACE_TYPE_ARG4
) (long) sig
) < 0)
1420 error (_("Can't detach %s: %s"),
1421 target_pid_to_str (ptid_of (thread
)),
1429 linux_detach (int pid
)
1431 struct process_info
*process
;
1433 process
= find_process_pid (pid
);
1434 if (process
== NULL
)
1437 /* As there's a step over already in progress, let it finish first,
1438 otherwise nesting a stabilize_threads operation on top gets real
1440 complete_ongoing_step_over ();
1442 /* Stop all threads before detaching. First, ptrace requires that
1443 the thread is stopped to sucessfully detach. Second, thread_db
1444 may need to uninstall thread event breakpoints from memory, which
1445 only works with a stopped process anyway. */
1446 stop_all_lwps (0, NULL
);
1448 #ifdef USE_THREAD_DB
1449 thread_db_detach (process
);
1452 /* Stabilize threads (move out of jump pads). */
1453 stabilize_threads ();
1455 find_inferior (&all_threads
, linux_detach_one_lwp
, &pid
);
1457 the_target
->mourn (process
);
1459 /* Since we presently can only stop all lwps of all processes, we
1460 need to unstop lwps of other processes. */
1461 unstop_all_lwps (0, NULL
);
1465 /* Remove all LWPs that belong to process PROC from the lwp list. */
1468 delete_lwp_callback (struct inferior_list_entry
*entry
, void *proc
)
1470 struct thread_info
*thread
= (struct thread_info
*) entry
;
1471 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1472 struct process_info
*process
= (struct process_info
*) proc
;
1474 if (pid_of (thread
) == pid_of (process
))
1481 linux_mourn (struct process_info
*process
)
1483 struct process_info_private
*priv
;
1485 #ifdef USE_THREAD_DB
1486 thread_db_mourn (process
);
1489 find_inferior (&all_threads
, delete_lwp_callback
, process
);
1491 /* Freeing all private data. */
1492 priv
= process
->priv
;
1493 free (priv
->arch_private
);
1495 process
->priv
= NULL
;
1497 remove_process (process
);
1501 linux_join (int pid
)
1506 ret
= my_waitpid (pid
, &status
, 0);
1507 if (WIFEXITED (status
) || WIFSIGNALED (status
))
1509 } while (ret
!= -1 || errno
!= ECHILD
);
1512 /* Return nonzero if the given thread is still alive. */
1514 linux_thread_alive (ptid_t ptid
)
1516 struct lwp_info
*lwp
= find_lwp_pid (ptid
);
1518 /* We assume we always know if a thread exits. If a whole process
1519 exited but we still haven't been able to report it to GDB, we'll
1520 hold on to the last lwp of the dead process. */
1522 return !lwp_is_marked_dead (lwp
);
1527 /* Return 1 if this lwp still has an interesting status pending. If
1528 not (e.g., it had stopped for a breakpoint that is gone), return
1532 thread_still_has_status_pending_p (struct thread_info
*thread
)
1534 struct lwp_info
*lp
= get_thread_lwp (thread
);
1536 if (!lp
->status_pending_p
)
1539 if (thread
->last_resume_kind
!= resume_stop
1540 && (lp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
1541 || lp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
1543 struct thread_info
*saved_thread
;
1547 gdb_assert (lp
->last_status
!= 0);
1551 saved_thread
= current_thread
;
1552 current_thread
= thread
;
1554 if (pc
!= lp
->stop_pc
)
1557 debug_printf ("PC of %ld changed\n",
1562 #if !USE_SIGTRAP_SIGINFO
1563 else if (lp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
1564 && !(*the_low_target
.breakpoint_at
) (pc
))
1567 debug_printf ("previous SW breakpoint of %ld gone\n",
1571 else if (lp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
1572 && !hardware_breakpoint_inserted_here (pc
))
1575 debug_printf ("previous HW breakpoint of %ld gone\n",
1581 current_thread
= saved_thread
;
1586 debug_printf ("discarding pending breakpoint status\n");
1587 lp
->status_pending_p
= 0;
1595 /* Returns true if LWP is resumed from the client's perspective. */
1598 lwp_resumed (struct lwp_info
*lwp
)
1600 struct thread_info
*thread
= get_lwp_thread (lwp
);
1602 if (thread
->last_resume_kind
!= resume_stop
)
1605 /* Did gdb send us a `vCont;t', but we haven't reported the
1606 corresponding stop to gdb yet? If so, the thread is still
1607 resumed/running from gdb's perspective. */
1608 if (thread
->last_resume_kind
== resume_stop
1609 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
)
1615 /* Return 1 if this lwp has an interesting status pending. */
1617 status_pending_p_callback (struct inferior_list_entry
*entry
, void *arg
)
1619 struct thread_info
*thread
= (struct thread_info
*) entry
;
1620 struct lwp_info
*lp
= get_thread_lwp (thread
);
1621 ptid_t ptid
= * (ptid_t
*) arg
;
1623 /* Check if we're only interested in events from a specific process
1624 or a specific LWP. */
1625 if (!ptid_match (ptid_of (thread
), ptid
))
1628 if (!lwp_resumed (lp
))
1631 if (lp
->status_pending_p
1632 && !thread_still_has_status_pending_p (thread
))
1634 linux_resume_one_lwp (lp
, lp
->stepping
, GDB_SIGNAL_0
, NULL
);
1638 return lp
->status_pending_p
;
1642 same_lwp (struct inferior_list_entry
*entry
, void *data
)
1644 ptid_t ptid
= *(ptid_t
*) data
;
1647 if (ptid_get_lwp (ptid
) != 0)
1648 lwp
= ptid_get_lwp (ptid
);
1650 lwp
= ptid_get_pid (ptid
);
1652 if (ptid_get_lwp (entry
->id
) == lwp
)
1659 find_lwp_pid (ptid_t ptid
)
1661 struct inferior_list_entry
*thread
1662 = find_inferior (&all_threads
, same_lwp
, &ptid
);
1667 return get_thread_lwp ((struct thread_info
*) thread
);
1670 /* Return the number of known LWPs in the tgid given by PID. */
1675 struct inferior_list_entry
*inf
, *tmp
;
1678 ALL_INFERIORS (&all_threads
, inf
, tmp
)
1680 if (ptid_get_pid (inf
->id
) == pid
)
1687 /* The arguments passed to iterate_over_lwps. */
1689 struct iterate_over_lwps_args
1691 /* The FILTER argument passed to iterate_over_lwps. */
1694 /* The CALLBACK argument passed to iterate_over_lwps. */
1695 iterate_over_lwps_ftype
*callback
;
1697 /* The DATA argument passed to iterate_over_lwps. */
1701 /* Callback for find_inferior used by iterate_over_lwps to filter
1702 calls to the callback supplied to that function. Returning a
1703 nonzero value causes find_inferiors to stop iterating and return
1704 the current inferior_list_entry. Returning zero indicates that
1705 find_inferiors should continue iterating. */
1708 iterate_over_lwps_filter (struct inferior_list_entry
*entry
, void *args_p
)
1710 struct iterate_over_lwps_args
*args
1711 = (struct iterate_over_lwps_args
*) args_p
;
1713 if (ptid_match (entry
->id
, args
->filter
))
1715 struct thread_info
*thr
= (struct thread_info
*) entry
;
1716 struct lwp_info
*lwp
= get_thread_lwp (thr
);
1718 return (*args
->callback
) (lwp
, args
->data
);
1724 /* See nat/linux-nat.h. */
1727 iterate_over_lwps (ptid_t filter
,
1728 iterate_over_lwps_ftype callback
,
1731 struct iterate_over_lwps_args args
= {filter
, callback
, data
};
1732 struct inferior_list_entry
*entry
;
1734 entry
= find_inferior (&all_threads
, iterate_over_lwps_filter
, &args
);
1738 return get_thread_lwp ((struct thread_info
*) entry
);
1741 /* Detect zombie thread group leaders, and "exit" them. We can't reap
1742 their exits until all other threads in the group have exited. */
1745 check_zombie_leaders (void)
1747 struct process_info
*proc
, *tmp
;
1749 ALL_PROCESSES (proc
, tmp
)
1751 pid_t leader_pid
= pid_of (proc
);
1752 struct lwp_info
*leader_lp
;
1754 leader_lp
= find_lwp_pid (pid_to_ptid (leader_pid
));
1757 debug_printf ("leader_pid=%d, leader_lp!=NULL=%d, "
1758 "num_lwps=%d, zombie=%d\n",
1759 leader_pid
, leader_lp
!= NULL
, num_lwps (leader_pid
),
1760 linux_proc_pid_is_zombie (leader_pid
));
1762 if (leader_lp
!= NULL
&& !leader_lp
->stopped
1763 /* Check if there are other threads in the group, as we may
1764 have raced with the inferior simply exiting. */
1765 && !last_thread_of_process_p (leader_pid
)
1766 && linux_proc_pid_is_zombie (leader_pid
))
1768 /* A leader zombie can mean one of two things:
1770 - It exited, and there's an exit status pending
1771 available, or only the leader exited (not the whole
1772 program). In the latter case, we can't waitpid the
1773 leader's exit status until all other threads are gone.
1775 - There are 3 or more threads in the group, and a thread
1776 other than the leader exec'd. On an exec, the Linux
1777 kernel destroys all other threads (except the execing
1778 one) in the thread group, and resets the execing thread's
1779 tid to the tgid. No exit notification is sent for the
1780 execing thread -- from the ptracer's perspective, it
1781 appears as though the execing thread just vanishes.
1782 Until we reap all other threads except the leader and the
1783 execing thread, the leader will be zombie, and the
1784 execing thread will be in `D (disc sleep)'. As soon as
1785 all other threads are reaped, the execing thread changes
1786 it's tid to the tgid, and the previous (zombie) leader
1787 vanishes, giving place to the "new" leader. We could try
1788 distinguishing the exit and exec cases, by waiting once
1789 more, and seeing if something comes out, but it doesn't
1790 sound useful. The previous leader _does_ go away, and
1791 we'll re-add the new one once we see the exec event
1792 (which is just the same as what would happen if the
1793 previous leader did exit voluntarily before some other
1798 "CZL: Thread group leader %d zombie "
1799 "(it exited, or another thread execd).\n",
1802 delete_lwp (leader_lp
);
1807 /* Callback for `find_inferior'. Returns the first LWP that is not
1808 stopped. ARG is a PTID filter. */
1811 not_stopped_callback (struct inferior_list_entry
*entry
, void *arg
)
1813 struct thread_info
*thr
= (struct thread_info
*) entry
;
1814 struct lwp_info
*lwp
;
1815 ptid_t filter
= *(ptid_t
*) arg
;
1817 if (!ptid_match (ptid_of (thr
), filter
))
1820 lwp
= get_thread_lwp (thr
);
1827 /* Increment LWP's suspend count. */
1830 lwp_suspended_inc (struct lwp_info
*lwp
)
1834 if (debug_threads
&& lwp
->suspended
> 4)
1836 struct thread_info
*thread
= get_lwp_thread (lwp
);
1838 debug_printf ("LWP %ld has a suspiciously high suspend count,"
1839 " suspended=%d\n", lwpid_of (thread
), lwp
->suspended
);
1843 /* Decrement LWP's suspend count. */
1846 lwp_suspended_decr (struct lwp_info
*lwp
)
1850 if (lwp
->suspended
< 0)
1852 struct thread_info
*thread
= get_lwp_thread (lwp
);
1854 internal_error (__FILE__
, __LINE__
,
1855 "unsuspend LWP %ld, suspended=%d\n", lwpid_of (thread
),
1860 /* This function should only be called if the LWP got a SIGTRAP.
1862 Handle any tracepoint steps or hits. Return true if a tracepoint
1863 event was handled, 0 otherwise. */
1866 handle_tracepoints (struct lwp_info
*lwp
)
1868 struct thread_info
*tinfo
= get_lwp_thread (lwp
);
1869 int tpoint_related_event
= 0;
1871 gdb_assert (lwp
->suspended
== 0);
1873 /* If this tracepoint hit causes a tracing stop, we'll immediately
1874 uninsert tracepoints. To do this, we temporarily pause all
1875 threads, unpatch away, and then unpause threads. We need to make
1876 sure the unpausing doesn't resume LWP too. */
1877 lwp_suspended_inc (lwp
);
1879 /* And we need to be sure that any all-threads-stopping doesn't try
1880 to move threads out of the jump pads, as it could deadlock the
1881 inferior (LWP could be in the jump pad, maybe even holding the
1884 /* Do any necessary step collect actions. */
1885 tpoint_related_event
|= tracepoint_finished_step (tinfo
, lwp
->stop_pc
);
1887 tpoint_related_event
|= handle_tracepoint_bkpts (tinfo
, lwp
->stop_pc
);
1889 /* See if we just hit a tracepoint and do its main collect
1891 tpoint_related_event
|= tracepoint_was_hit (tinfo
, lwp
->stop_pc
);
1893 lwp_suspended_decr (lwp
);
1895 gdb_assert (lwp
->suspended
== 0);
1896 gdb_assert (!stabilizing_threads
|| lwp
->collecting_fast_tracepoint
);
1898 if (tpoint_related_event
)
1901 debug_printf ("got a tracepoint event\n");
1908 /* Convenience wrapper. Returns true if LWP is presently collecting a
1912 linux_fast_tracepoint_collecting (struct lwp_info
*lwp
,
1913 struct fast_tpoint_collect_status
*status
)
1915 CORE_ADDR thread_area
;
1916 struct thread_info
*thread
= get_lwp_thread (lwp
);
1918 if (the_low_target
.get_thread_area
== NULL
)
1921 /* Get the thread area address. This is used to recognize which
1922 thread is which when tracing with the in-process agent library.
1923 We don't read anything from the address, and treat it as opaque;
1924 it's the address itself that we assume is unique per-thread. */
1925 if ((*the_low_target
.get_thread_area
) (lwpid_of (thread
), &thread_area
) == -1)
1928 return fast_tracepoint_collecting (thread_area
, lwp
->stop_pc
, status
);
1931 /* The reason we resume in the caller, is because we want to be able
1932 to pass lwp->status_pending as WSTAT, and we need to clear
1933 status_pending_p before resuming, otherwise, linux_resume_one_lwp
1934 refuses to resume. */
1937 maybe_move_out_of_jump_pad (struct lwp_info
*lwp
, int *wstat
)
1939 struct thread_info
*saved_thread
;
1941 saved_thread
= current_thread
;
1942 current_thread
= get_lwp_thread (lwp
);
1945 || (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) != SIGTRAP
))
1946 && supports_fast_tracepoints ()
1947 && agent_loaded_p ())
1949 struct fast_tpoint_collect_status status
;
1953 debug_printf ("Checking whether LWP %ld needs to move out of the "
1955 lwpid_of (current_thread
));
1957 r
= linux_fast_tracepoint_collecting (lwp
, &status
);
1960 || (WSTOPSIG (*wstat
) != SIGILL
1961 && WSTOPSIG (*wstat
) != SIGFPE
1962 && WSTOPSIG (*wstat
) != SIGSEGV
1963 && WSTOPSIG (*wstat
) != SIGBUS
))
1965 lwp
->collecting_fast_tracepoint
= r
;
1969 if (r
== 1 && lwp
->exit_jump_pad_bkpt
== NULL
)
1971 /* Haven't executed the original instruction yet.
1972 Set breakpoint there, and wait till it's hit,
1973 then single-step until exiting the jump pad. */
1974 lwp
->exit_jump_pad_bkpt
1975 = set_breakpoint_at (status
.adjusted_insn_addr
, NULL
);
1979 debug_printf ("Checking whether LWP %ld needs to move out of "
1980 "the jump pad...it does\n",
1981 lwpid_of (current_thread
));
1982 current_thread
= saved_thread
;
1989 /* If we get a synchronous signal while collecting, *and*
1990 while executing the (relocated) original instruction,
1991 reset the PC to point at the tpoint address, before
1992 reporting to GDB. Otherwise, it's an IPA lib bug: just
1993 report the signal to GDB, and pray for the best. */
1995 lwp
->collecting_fast_tracepoint
= 0;
1998 && (status
.adjusted_insn_addr
<= lwp
->stop_pc
1999 && lwp
->stop_pc
< status
.adjusted_insn_addr_end
))
2002 struct regcache
*regcache
;
2004 /* The si_addr on a few signals references the address
2005 of the faulting instruction. Adjust that as
2007 if ((WSTOPSIG (*wstat
) == SIGILL
2008 || WSTOPSIG (*wstat
) == SIGFPE
2009 || WSTOPSIG (*wstat
) == SIGBUS
2010 || WSTOPSIG (*wstat
) == SIGSEGV
)
2011 && ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
2012 (PTRACE_TYPE_ARG3
) 0, &info
) == 0
2013 /* Final check just to make sure we don't clobber
2014 the siginfo of non-kernel-sent signals. */
2015 && (uintptr_t) info
.si_addr
== lwp
->stop_pc
)
2017 info
.si_addr
= (void *) (uintptr_t) status
.tpoint_addr
;
2018 ptrace (PTRACE_SETSIGINFO
, lwpid_of (current_thread
),
2019 (PTRACE_TYPE_ARG3
) 0, &info
);
2022 regcache
= get_thread_regcache (current_thread
, 1);
2023 (*the_low_target
.set_pc
) (regcache
, status
.tpoint_addr
);
2024 lwp
->stop_pc
= status
.tpoint_addr
;
2026 /* Cancel any fast tracepoint lock this thread was
2028 force_unlock_trace_buffer ();
2031 if (lwp
->exit_jump_pad_bkpt
!= NULL
)
2034 debug_printf ("Cancelling fast exit-jump-pad: removing bkpt. "
2035 "stopping all threads momentarily.\n");
2037 stop_all_lwps (1, lwp
);
2039 delete_breakpoint (lwp
->exit_jump_pad_bkpt
);
2040 lwp
->exit_jump_pad_bkpt
= NULL
;
2042 unstop_all_lwps (1, lwp
);
2044 gdb_assert (lwp
->suspended
>= 0);
2050 debug_printf ("Checking whether LWP %ld needs to move out of the "
2052 lwpid_of (current_thread
));
2054 current_thread
= saved_thread
;
2058 /* Enqueue one signal in the "signals to report later when out of the
2062 enqueue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
2064 struct pending_signals
*p_sig
;
2065 struct thread_info
*thread
= get_lwp_thread (lwp
);
2068 debug_printf ("Deferring signal %d for LWP %ld.\n",
2069 WSTOPSIG (*wstat
), lwpid_of (thread
));
2073 struct pending_signals
*sig
;
2075 for (sig
= lwp
->pending_signals_to_report
;
2078 debug_printf (" Already queued %d\n",
2081 debug_printf (" (no more currently queued signals)\n");
2084 /* Don't enqueue non-RT signals if they are already in the deferred
2085 queue. (SIGSTOP being the easiest signal to see ending up here
2087 if (WSTOPSIG (*wstat
) < __SIGRTMIN
)
2089 struct pending_signals
*sig
;
2091 for (sig
= lwp
->pending_signals_to_report
;
2095 if (sig
->signal
== WSTOPSIG (*wstat
))
2098 debug_printf ("Not requeuing already queued non-RT signal %d"
2107 p_sig
= XCNEW (struct pending_signals
);
2108 p_sig
->prev
= lwp
->pending_signals_to_report
;
2109 p_sig
->signal
= WSTOPSIG (*wstat
);
2111 ptrace (PTRACE_GETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
2114 lwp
->pending_signals_to_report
= p_sig
;
2117 /* Dequeue one signal from the "signals to report later when out of
2118 the jump pad" list. */
2121 dequeue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
2123 struct thread_info
*thread
= get_lwp_thread (lwp
);
2125 if (lwp
->pending_signals_to_report
!= NULL
)
2127 struct pending_signals
**p_sig
;
2129 p_sig
= &lwp
->pending_signals_to_report
;
2130 while ((*p_sig
)->prev
!= NULL
)
2131 p_sig
= &(*p_sig
)->prev
;
2133 *wstat
= W_STOPCODE ((*p_sig
)->signal
);
2134 if ((*p_sig
)->info
.si_signo
!= 0)
2135 ptrace (PTRACE_SETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
2141 debug_printf ("Reporting deferred signal %d for LWP %ld.\n",
2142 WSTOPSIG (*wstat
), lwpid_of (thread
));
2146 struct pending_signals
*sig
;
2148 for (sig
= lwp
->pending_signals_to_report
;
2151 debug_printf (" Still queued %d\n",
2154 debug_printf (" (no more queued signals)\n");
2163 /* Fetch the possibly triggered data watchpoint info and store it in
2166 On some archs, like x86, that use debug registers to set
2167 watchpoints, it's possible that the way to know which watched
2168 address trapped, is to check the register that is used to select
2169 which address to watch. Problem is, between setting the watchpoint
2170 and reading back which data address trapped, the user may change
2171 the set of watchpoints, and, as a consequence, GDB changes the
2172 debug registers in the inferior. To avoid reading back a stale
2173 stopped-data-address when that happens, we cache in LP the fact
2174 that a watchpoint trapped, and the corresponding data address, as
2175 soon as we see CHILD stop with a SIGTRAP. If GDB changes the debug
2176 registers meanwhile, we have the cached data we can rely on. */
2179 check_stopped_by_watchpoint (struct lwp_info
*child
)
2181 if (the_low_target
.stopped_by_watchpoint
!= NULL
)
2183 struct thread_info
*saved_thread
;
2185 saved_thread
= current_thread
;
2186 current_thread
= get_lwp_thread (child
);
2188 if (the_low_target
.stopped_by_watchpoint ())
2190 child
->stop_reason
= TARGET_STOPPED_BY_WATCHPOINT
;
2192 if (the_low_target
.stopped_data_address
!= NULL
)
2193 child
->stopped_data_address
2194 = the_low_target
.stopped_data_address ();
2196 child
->stopped_data_address
= 0;
2199 current_thread
= saved_thread
;
2202 return child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
;
2205 /* Return the ptrace options that we want to try to enable. */
2208 linux_low_ptrace_options (int attached
)
2213 options
|= PTRACE_O_EXITKILL
;
2215 if (report_fork_events
)
2216 options
|= PTRACE_O_TRACEFORK
;
2218 if (report_vfork_events
)
2219 options
|= (PTRACE_O_TRACEVFORK
| PTRACE_O_TRACEVFORKDONE
);
2221 if (report_exec_events
)
2222 options
|= PTRACE_O_TRACEEXEC
;
2227 /* Do low-level handling of the event, and check if we should go on
2228 and pass it to caller code. Return the affected lwp if we are, or
2231 static struct lwp_info
*
2232 linux_low_filter_event (int lwpid
, int wstat
)
2234 struct lwp_info
*child
;
2235 struct thread_info
*thread
;
2236 int have_stop_pc
= 0;
2238 child
= find_lwp_pid (pid_to_ptid (lwpid
));
2240 /* Check for stop events reported by a process we didn't already
2241 know about - anything not already in our LWP list.
2243 If we're expecting to receive stopped processes after
2244 fork, vfork, and clone events, then we'll just add the
2245 new one to our list and go back to waiting for the event
2246 to be reported - the stopped process might be returned
2247 from waitpid before or after the event is.
2249 But note the case of a non-leader thread exec'ing after the
2250 leader having exited, and gone from our lists (because
2251 check_zombie_leaders deleted it). The non-leader thread
2252 changes its tid to the tgid. */
2254 if (WIFSTOPPED (wstat
) && child
== NULL
&& WSTOPSIG (wstat
) == SIGTRAP
2255 && linux_ptrace_get_extended_event (wstat
) == PTRACE_EVENT_EXEC
)
2259 /* A multi-thread exec after we had seen the leader exiting. */
2262 debug_printf ("LLW: Re-adding thread group leader LWP %d"
2263 "after exec.\n", lwpid
);
2266 child_ptid
= ptid_build (lwpid
, lwpid
, 0);
2267 child
= add_lwp (child_ptid
);
2269 current_thread
= child
->thread
;
2272 /* If we didn't find a process, one of two things presumably happened:
2273 - A process we started and then detached from has exited. Ignore it.
2274 - A process we are controlling has forked and the new child's stop
2275 was reported to us by the kernel. Save its PID. */
2276 if (child
== NULL
&& WIFSTOPPED (wstat
))
2278 add_to_pid_list (&stopped_pids
, lwpid
, wstat
);
2281 else if (child
== NULL
)
2284 thread
= get_lwp_thread (child
);
2288 child
->last_status
= wstat
;
2290 /* Check if the thread has exited. */
2291 if ((WIFEXITED (wstat
) || WIFSIGNALED (wstat
)))
2294 debug_printf ("LLFE: %d exited.\n", lwpid
);
2295 /* If there is at least one more LWP, then the exit signal was
2296 not the end of the debugged application and should be
2297 ignored, unless GDB wants to hear about thread exits. */
2298 if (report_thread_events
2299 || last_thread_of_process_p (pid_of (thread
)))
2301 /* Since events are serialized to GDB core, and we can't
2302 report this one right now. Leave the status pending for
2303 the next time we're able to report it. */
2304 mark_lwp_dead (child
, wstat
);
2314 gdb_assert (WIFSTOPPED (wstat
));
2316 if (WIFSTOPPED (wstat
))
2318 struct process_info
*proc
;
2320 /* Architecture-specific setup after inferior is running. */
2321 proc
= find_process_pid (pid_of (thread
));
2322 if (proc
->tdesc
== NULL
)
2326 /* This needs to happen after we have attached to the
2327 inferior and it is stopped for the first time, but
2328 before we access any inferior registers. */
2329 linux_arch_setup_thread (thread
);
2333 /* The process is started, but GDBserver will do
2334 architecture-specific setup after the program stops at
2335 the first instruction. */
2336 child
->status_pending_p
= 1;
2337 child
->status_pending
= wstat
;
2343 if (WIFSTOPPED (wstat
) && child
->must_set_ptrace_flags
)
2345 struct process_info
*proc
= find_process_pid (pid_of (thread
));
2346 int options
= linux_low_ptrace_options (proc
->attached
);
2348 linux_enable_event_reporting (lwpid
, options
);
2349 child
->must_set_ptrace_flags
= 0;
2352 /* Be careful to not overwrite stop_pc until
2353 check_stopped_by_breakpoint is called. */
2354 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGTRAP
2355 && linux_is_extended_waitstatus (wstat
))
2357 child
->stop_pc
= get_pc (child
);
2358 if (handle_extended_wait (&child
, wstat
))
2360 /* The event has been handled, so just return without
2366 /* Check first whether this was a SW/HW breakpoint before checking
2367 watchpoints, because at least s390 can't tell the data address of
2368 hardware watchpoint hits, and returns stopped-by-watchpoint as
2369 long as there's a watchpoint set. */
2370 if (WIFSTOPPED (wstat
) && linux_wstatus_maybe_breakpoint (wstat
))
2372 if (check_stopped_by_breakpoint (child
))
2376 /* Note that TRAP_HWBKPT can indicate either a hardware breakpoint
2377 or hardware watchpoint. Check which is which if we got
2378 TARGET_STOPPED_BY_HW_BREAKPOINT. Likewise, we may have single
2379 stepped an instruction that triggered a watchpoint. In that
2380 case, on some architectures (such as x86), instead of
2381 TRAP_HWBKPT, si_code indicates TRAP_TRACE, and we need to check
2382 the debug registers separately. */
2383 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGTRAP
2384 && child
->stop_reason
!= TARGET_STOPPED_BY_SW_BREAKPOINT
)
2385 check_stopped_by_watchpoint (child
);
2388 child
->stop_pc
= get_pc (child
);
2390 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGSTOP
2391 && child
->stop_expected
)
2394 debug_printf ("Expected stop.\n");
2395 child
->stop_expected
= 0;
2397 if (thread
->last_resume_kind
== resume_stop
)
2399 /* We want to report the stop to the core. Treat the
2400 SIGSTOP as a normal event. */
2402 debug_printf ("LLW: resume_stop SIGSTOP caught for %s.\n",
2403 target_pid_to_str (ptid_of (thread
)));
2405 else if (stopping_threads
!= NOT_STOPPING_THREADS
)
2407 /* Stopping threads. We don't want this SIGSTOP to end up
2410 debug_printf ("LLW: SIGSTOP caught for %s "
2411 "while stopping threads.\n",
2412 target_pid_to_str (ptid_of (thread
)));
2417 /* This is a delayed SIGSTOP. Filter out the event. */
2419 debug_printf ("LLW: %s %s, 0, 0 (discard delayed SIGSTOP)\n",
2420 child
->stepping
? "step" : "continue",
2421 target_pid_to_str (ptid_of (thread
)));
2423 linux_resume_one_lwp (child
, child
->stepping
, 0, NULL
);
2428 child
->status_pending_p
= 1;
2429 child
->status_pending
= wstat
;
2433 /* Resume LWPs that are currently stopped without any pending status
2434 to report, but are resumed from the core's perspective. */
2437 resume_stopped_resumed_lwps (struct inferior_list_entry
*entry
)
2439 struct thread_info
*thread
= (struct thread_info
*) entry
;
2440 struct lwp_info
*lp
= get_thread_lwp (thread
);
2444 && !lp
->status_pending_p
2445 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
)
2447 int step
= thread
->last_resume_kind
== resume_step
;
2450 debug_printf ("RSRL: resuming stopped-resumed LWP %s at %s: step=%d\n",
2451 target_pid_to_str (ptid_of (thread
)),
2452 paddress (lp
->stop_pc
),
2455 linux_resume_one_lwp (lp
, step
, GDB_SIGNAL_0
, NULL
);
2459 /* Wait for an event from child(ren) WAIT_PTID, and return any that
2460 match FILTER_PTID (leaving others pending). The PTIDs can be:
2461 minus_one_ptid, to specify any child; a pid PTID, specifying all
2462 lwps of a thread group; or a PTID representing a single lwp. Store
2463 the stop status through the status pointer WSTAT. OPTIONS is
2464 passed to the waitpid call. Return 0 if no event was found and
2465 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
2466 was found. Return the PID of the stopped child otherwise. */
2469 linux_wait_for_event_filtered (ptid_t wait_ptid
, ptid_t filter_ptid
,
2470 int *wstatp
, int options
)
2472 struct thread_info
*event_thread
;
2473 struct lwp_info
*event_child
, *requested_child
;
2474 sigset_t block_mask
, prev_mask
;
2477 /* N.B. event_thread points to the thread_info struct that contains
2478 event_child. Keep them in sync. */
2479 event_thread
= NULL
;
2481 requested_child
= NULL
;
2483 /* Check for a lwp with a pending status. */
2485 if (ptid_equal (filter_ptid
, minus_one_ptid
) || ptid_is_pid (filter_ptid
))
2487 event_thread
= (struct thread_info
*)
2488 find_inferior (&all_threads
, status_pending_p_callback
, &filter_ptid
);
2489 if (event_thread
!= NULL
)
2490 event_child
= get_thread_lwp (event_thread
);
2491 if (debug_threads
&& event_thread
)
2492 debug_printf ("Got a pending child %ld\n", lwpid_of (event_thread
));
2494 else if (!ptid_equal (filter_ptid
, null_ptid
))
2496 requested_child
= find_lwp_pid (filter_ptid
);
2498 if (stopping_threads
== NOT_STOPPING_THREADS
2499 && requested_child
->status_pending_p
2500 && requested_child
->collecting_fast_tracepoint
)
2502 enqueue_one_deferred_signal (requested_child
,
2503 &requested_child
->status_pending
);
2504 requested_child
->status_pending_p
= 0;
2505 requested_child
->status_pending
= 0;
2506 linux_resume_one_lwp (requested_child
, 0, 0, NULL
);
2509 if (requested_child
->suspended
2510 && requested_child
->status_pending_p
)
2512 internal_error (__FILE__
, __LINE__
,
2513 "requesting an event out of a"
2514 " suspended child?");
2517 if (requested_child
->status_pending_p
)
2519 event_child
= requested_child
;
2520 event_thread
= get_lwp_thread (event_child
);
2524 if (event_child
!= NULL
)
2527 debug_printf ("Got an event from pending child %ld (%04x)\n",
2528 lwpid_of (event_thread
), event_child
->status_pending
);
2529 *wstatp
= event_child
->status_pending
;
2530 event_child
->status_pending_p
= 0;
2531 event_child
->status_pending
= 0;
2532 current_thread
= event_thread
;
2533 return lwpid_of (event_thread
);
2536 /* But if we don't find a pending event, we'll have to wait.
2538 We only enter this loop if no process has a pending wait status.
2539 Thus any action taken in response to a wait status inside this
2540 loop is responding as soon as we detect the status, not after any
2543 /* Make sure SIGCHLD is blocked until the sigsuspend below. Block
2544 all signals while here. */
2545 sigfillset (&block_mask
);
2546 sigprocmask (SIG_BLOCK
, &block_mask
, &prev_mask
);
2548 /* Always pull all events out of the kernel. We'll randomly select
2549 an event LWP out of all that have events, to prevent
2551 while (event_child
== NULL
)
2555 /* Always use -1 and WNOHANG, due to couple of a kernel/ptrace
2558 - If the thread group leader exits while other threads in the
2559 thread group still exist, waitpid(TGID, ...) hangs. That
2560 waitpid won't return an exit status until the other threads
2561 in the group are reaped.
2563 - When a non-leader thread execs, that thread just vanishes
2564 without reporting an exit (so we'd hang if we waited for it
2565 explicitly in that case). The exec event is reported to
2568 ret
= my_waitpid (-1, wstatp
, options
| WNOHANG
);
2571 debug_printf ("LWFE: waitpid(-1, ...) returned %d, %s\n",
2572 ret
, errno
? strerror (errno
) : "ERRNO-OK");
2578 debug_printf ("LLW: waitpid %ld received %s\n",
2579 (long) ret
, status_to_str (*wstatp
));
2582 /* Filter all events. IOW, leave all events pending. We'll
2583 randomly select an event LWP out of all that have events
2585 linux_low_filter_event (ret
, *wstatp
);
2586 /* Retry until nothing comes out of waitpid. A single
2587 SIGCHLD can indicate more than one child stopped. */
2591 /* Now that we've pulled all events out of the kernel, resume
2592 LWPs that don't have an interesting event to report. */
2593 if (stopping_threads
== NOT_STOPPING_THREADS
)
2594 for_each_inferior (&all_threads
, resume_stopped_resumed_lwps
);
2596 /* ... and find an LWP with a status to report to the core, if
2598 event_thread
= (struct thread_info
*)
2599 find_inferior (&all_threads
, status_pending_p_callback
, &filter_ptid
);
2600 if (event_thread
!= NULL
)
2602 event_child
= get_thread_lwp (event_thread
);
2603 *wstatp
= event_child
->status_pending
;
2604 event_child
->status_pending_p
= 0;
2605 event_child
->status_pending
= 0;
2609 /* Check for zombie thread group leaders. Those can't be reaped
2610 until all other threads in the thread group are. */
2611 check_zombie_leaders ();
2613 /* If there are no resumed children left in the set of LWPs we
2614 want to wait for, bail. We can't just block in
2615 waitpid/sigsuspend, because lwps might have been left stopped
2616 in trace-stop state, and we'd be stuck forever waiting for
2617 their status to change (which would only happen if we resumed
2618 them). Even if WNOHANG is set, this return code is preferred
2619 over 0 (below), as it is more detailed. */
2620 if ((find_inferior (&all_threads
,
2621 not_stopped_callback
,
2622 &wait_ptid
) == NULL
))
2625 debug_printf ("LLW: exit (no unwaited-for LWP)\n");
2626 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2630 /* No interesting event to report to the caller. */
2631 if ((options
& WNOHANG
))
2634 debug_printf ("WNOHANG set, no event found\n");
2636 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2640 /* Block until we get an event reported with SIGCHLD. */
2642 debug_printf ("sigsuspend'ing\n");
2644 sigsuspend (&prev_mask
);
2645 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2649 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2651 current_thread
= event_thread
;
2653 return lwpid_of (event_thread
);
2656 /* Wait for an event from child(ren) PTID. PTIDs can be:
2657 minus_one_ptid, to specify any child; a pid PTID, specifying all
2658 lwps of a thread group; or a PTID representing a single lwp. Store
2659 the stop status through the status pointer WSTAT. OPTIONS is
2660 passed to the waitpid call. Return 0 if no event was found and
2661 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
2662 was found. Return the PID of the stopped child otherwise. */
2665 linux_wait_for_event (ptid_t ptid
, int *wstatp
, int options
)
2667 return linux_wait_for_event_filtered (ptid
, ptid
, wstatp
, options
);
2670 /* Count the LWP's that have had events. */
2673 count_events_callback (struct inferior_list_entry
*entry
, void *data
)
2675 struct thread_info
*thread
= (struct thread_info
*) entry
;
2676 struct lwp_info
*lp
= get_thread_lwp (thread
);
2677 int *count
= (int *) data
;
2679 gdb_assert (count
!= NULL
);
2681 /* Count only resumed LWPs that have an event pending. */
2682 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2683 && lp
->status_pending_p
)
2689 /* Select the LWP (if any) that is currently being single-stepped. */
2692 select_singlestep_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
2694 struct thread_info
*thread
= (struct thread_info
*) entry
;
2695 struct lwp_info
*lp
= get_thread_lwp (thread
);
2697 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2698 && thread
->last_resume_kind
== resume_step
2699 && lp
->status_pending_p
)
2705 /* Select the Nth LWP that has had an event. */
2708 select_event_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
2710 struct thread_info
*thread
= (struct thread_info
*) entry
;
2711 struct lwp_info
*lp
= get_thread_lwp (thread
);
2712 int *selector
= (int *) data
;
2714 gdb_assert (selector
!= NULL
);
2716 /* Select only resumed LWPs that have an event pending. */
2717 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2718 && lp
->status_pending_p
)
2719 if ((*selector
)-- == 0)
2725 /* Select one LWP out of those that have events pending. */
2728 select_event_lwp (struct lwp_info
**orig_lp
)
2731 int random_selector
;
2732 struct thread_info
*event_thread
= NULL
;
2734 /* In all-stop, give preference to the LWP that is being
2735 single-stepped. There will be at most one, and it's the LWP that
2736 the core is most interested in. If we didn't do this, then we'd
2737 have to handle pending step SIGTRAPs somehow in case the core
2738 later continues the previously-stepped thread, otherwise we'd
2739 report the pending SIGTRAP, and the core, not having stepped the
2740 thread, wouldn't understand what the trap was for, and therefore
2741 would report it to the user as a random signal. */
2745 = (struct thread_info
*) find_inferior (&all_threads
,
2746 select_singlestep_lwp_callback
,
2748 if (event_thread
!= NULL
)
2751 debug_printf ("SEL: Select single-step %s\n",
2752 target_pid_to_str (ptid_of (event_thread
)));
2755 if (event_thread
== NULL
)
2757 /* No single-stepping LWP. Select one at random, out of those
2758 which have had events. */
2760 /* First see how many events we have. */
2761 find_inferior (&all_threads
, count_events_callback
, &num_events
);
2762 gdb_assert (num_events
> 0);
2764 /* Now randomly pick a LWP out of those that have had
2766 random_selector
= (int)
2767 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
2769 if (debug_threads
&& num_events
> 1)
2770 debug_printf ("SEL: Found %d SIGTRAP events, selecting #%d\n",
2771 num_events
, random_selector
);
2774 = (struct thread_info
*) find_inferior (&all_threads
,
2775 select_event_lwp_callback
,
2779 if (event_thread
!= NULL
)
2781 struct lwp_info
*event_lp
= get_thread_lwp (event_thread
);
2783 /* Switch the event LWP. */
2784 *orig_lp
= event_lp
;
2788 /* Decrement the suspend count of an LWP. */
2791 unsuspend_one_lwp (struct inferior_list_entry
*entry
, void *except
)
2793 struct thread_info
*thread
= (struct thread_info
*) entry
;
2794 struct lwp_info
*lwp
= get_thread_lwp (thread
);
2796 /* Ignore EXCEPT. */
2800 lwp_suspended_decr (lwp
);
2804 /* Decrement the suspend count of all LWPs, except EXCEPT, if non
2808 unsuspend_all_lwps (struct lwp_info
*except
)
2810 find_inferior (&all_threads
, unsuspend_one_lwp
, except
);
2813 static void move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
);
2814 static int stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
,
2816 static int lwp_running (struct inferior_list_entry
*entry
, void *data
);
2817 static ptid_t
linux_wait_1 (ptid_t ptid
,
2818 struct target_waitstatus
*ourstatus
,
2819 int target_options
);
2821 /* Stabilize threads (move out of jump pads).
2823 If a thread is midway collecting a fast tracepoint, we need to
2824 finish the collection and move it out of the jump pad before
2825 reporting the signal.
2827 This avoids recursion while collecting (when a signal arrives
2828 midway, and the signal handler itself collects), which would trash
2829 the trace buffer. In case the user set a breakpoint in a signal
2830 handler, this avoids the backtrace showing the jump pad, etc..
2831 Most importantly, there are certain things we can't do safely if
2832 threads are stopped in a jump pad (or in its callee's). For
2835 - starting a new trace run. A thread still collecting the
2836 previous run, could trash the trace buffer when resumed. The trace
2837 buffer control structures would have been reset but the thread had
2838 no way to tell. The thread could even midway memcpy'ing to the
2839 buffer, which would mean that when resumed, it would clobber the
2840 trace buffer that had been set for a new run.
2842 - we can't rewrite/reuse the jump pads for new tracepoints
2843 safely. Say you do tstart while a thread is stopped midway while
2844 collecting. When the thread is later resumed, it finishes the
2845 collection, and returns to the jump pad, to execute the original
2846 instruction that was under the tracepoint jump at the time the
2847 older run had been started. If the jump pad had been rewritten
2848 since for something else in the new run, the thread would now
2849 execute the wrong / random instructions. */
2852 linux_stabilize_threads (void)
2854 struct thread_info
*saved_thread
;
2855 struct thread_info
*thread_stuck
;
2858 = (struct thread_info
*) find_inferior (&all_threads
,
2859 stuck_in_jump_pad_callback
,
2861 if (thread_stuck
!= NULL
)
2864 debug_printf ("can't stabilize, LWP %ld is stuck in jump pad\n",
2865 lwpid_of (thread_stuck
));
2869 saved_thread
= current_thread
;
2871 stabilizing_threads
= 1;
2874 for_each_inferior (&all_threads
, move_out_of_jump_pad_callback
);
2876 /* Loop until all are stopped out of the jump pads. */
2877 while (find_inferior (&all_threads
, lwp_running
, NULL
) != NULL
)
2879 struct target_waitstatus ourstatus
;
2880 struct lwp_info
*lwp
;
2883 /* Note that we go through the full wait even loop. While
2884 moving threads out of jump pad, we need to be able to step
2885 over internal breakpoints and such. */
2886 linux_wait_1 (minus_one_ptid
, &ourstatus
, 0);
2888 if (ourstatus
.kind
== TARGET_WAITKIND_STOPPED
)
2890 lwp
= get_thread_lwp (current_thread
);
2893 lwp_suspended_inc (lwp
);
2895 if (ourstatus
.value
.sig
!= GDB_SIGNAL_0
2896 || current_thread
->last_resume_kind
== resume_stop
)
2898 wstat
= W_STOPCODE (gdb_signal_to_host (ourstatus
.value
.sig
));
2899 enqueue_one_deferred_signal (lwp
, &wstat
);
2904 find_inferior (&all_threads
, unsuspend_one_lwp
, NULL
);
2906 stabilizing_threads
= 0;
2908 current_thread
= saved_thread
;
2913 = (struct thread_info
*) find_inferior (&all_threads
,
2914 stuck_in_jump_pad_callback
,
2916 if (thread_stuck
!= NULL
)
2917 debug_printf ("couldn't stabilize, LWP %ld got stuck in jump pad\n",
2918 lwpid_of (thread_stuck
));
2922 /* Convenience function that is called when the kernel reports an
2923 event that is not passed out to GDB. */
2926 ignore_event (struct target_waitstatus
*ourstatus
)
2928 /* If we got an event, there may still be others, as a single
2929 SIGCHLD can indicate more than one child stopped. This forces
2930 another target_wait call. */
2933 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2937 /* Convenience function that is called when the kernel reports an exit
2938 event. This decides whether to report the event to GDB as a
2939 process exit event, a thread exit event, or to suppress the
2943 filter_exit_event (struct lwp_info
*event_child
,
2944 struct target_waitstatus
*ourstatus
)
2946 struct thread_info
*thread
= get_lwp_thread (event_child
);
2947 ptid_t ptid
= ptid_of (thread
);
2949 if (!last_thread_of_process_p (pid_of (thread
)))
2951 if (report_thread_events
)
2952 ourstatus
->kind
= TARGET_WAITKIND_THREAD_EXITED
;
2954 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2956 delete_lwp (event_child
);
2961 /* Wait for process, returns status. */
2964 linux_wait_1 (ptid_t ptid
,
2965 struct target_waitstatus
*ourstatus
, int target_options
)
2968 struct lwp_info
*event_child
;
2971 int step_over_finished
;
2972 int bp_explains_trap
;
2973 int maybe_internal_trap
;
2982 debug_printf ("linux_wait_1: [%s]\n", target_pid_to_str (ptid
));
2985 /* Translate generic target options into linux options. */
2987 if (target_options
& TARGET_WNOHANG
)
2990 bp_explains_trap
= 0;
2993 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2995 /* Find a resumed LWP, if any. */
2996 if (find_inferior (&all_threads
,
2997 status_pending_p_callback
,
2998 &minus_one_ptid
) != NULL
)
3000 else if ((find_inferior (&all_threads
,
3001 not_stopped_callback
,
3002 &minus_one_ptid
) != NULL
))
3007 if (ptid_equal (step_over_bkpt
, null_ptid
))
3008 pid
= linux_wait_for_event (ptid
, &w
, options
);
3012 debug_printf ("step_over_bkpt set [%s], doing a blocking wait\n",
3013 target_pid_to_str (step_over_bkpt
));
3014 pid
= linux_wait_for_event (step_over_bkpt
, &w
, options
& ~WNOHANG
);
3017 if (pid
== 0 || (pid
== -1 && !any_resumed
))
3019 gdb_assert (target_options
& TARGET_WNOHANG
);
3023 debug_printf ("linux_wait_1 ret = null_ptid, "
3024 "TARGET_WAITKIND_IGNORE\n");
3028 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
3035 debug_printf ("linux_wait_1 ret = null_ptid, "
3036 "TARGET_WAITKIND_NO_RESUMED\n");
3040 ourstatus
->kind
= TARGET_WAITKIND_NO_RESUMED
;
3044 event_child
= get_thread_lwp (current_thread
);
3046 /* linux_wait_for_event only returns an exit status for the last
3047 child of a process. Report it. */
3048 if (WIFEXITED (w
) || WIFSIGNALED (w
))
3052 ourstatus
->kind
= TARGET_WAITKIND_EXITED
;
3053 ourstatus
->value
.integer
= WEXITSTATUS (w
);
3057 debug_printf ("linux_wait_1 ret = %s, exited with "
3059 target_pid_to_str (ptid_of (current_thread
)),
3066 ourstatus
->kind
= TARGET_WAITKIND_SIGNALLED
;
3067 ourstatus
->value
.sig
= gdb_signal_from_host (WTERMSIG (w
));
3071 debug_printf ("linux_wait_1 ret = %s, terminated with "
3073 target_pid_to_str (ptid_of (current_thread
)),
3079 if (ourstatus
->kind
== TARGET_WAITKIND_EXITED
)
3080 return filter_exit_event (event_child
, ourstatus
);
3082 return ptid_of (current_thread
);
3085 /* If step-over executes a breakpoint instruction, in the case of a
3086 hardware single step it means a gdb/gdbserver breakpoint had been
3087 planted on top of a permanent breakpoint, in the case of a software
3088 single step it may just mean that gdbserver hit the reinsert breakpoint.
3089 The PC has been adjusted by check_stopped_by_breakpoint to point at
3090 the breakpoint address.
3091 So in the case of the hardware single step advance the PC manually
3092 past the breakpoint and in the case of software single step advance only
3093 if it's not the reinsert_breakpoint we are hitting.
3094 This avoids that a program would keep trapping a permanent breakpoint
3096 if (!ptid_equal (step_over_bkpt
, null_ptid
)
3097 && event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3098 && (event_child
->stepping
3099 || !reinsert_breakpoint_inserted_here (event_child
->stop_pc
)))
3101 int increment_pc
= 0;
3102 int breakpoint_kind
= 0;
3103 CORE_ADDR stop_pc
= event_child
->stop_pc
;
3106 the_target
->breakpoint_kind_from_current_state (&stop_pc
);
3107 the_target
->sw_breakpoint_from_kind (breakpoint_kind
, &increment_pc
);
3111 debug_printf ("step-over for %s executed software breakpoint\n",
3112 target_pid_to_str (ptid_of (current_thread
)));
3115 if (increment_pc
!= 0)
3117 struct regcache
*regcache
3118 = get_thread_regcache (current_thread
, 1);
3120 event_child
->stop_pc
+= increment_pc
;
3121 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
3123 if (!(*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))
3124 event_child
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3128 /* If this event was not handled before, and is not a SIGTRAP, we
3129 report it. SIGILL and SIGSEGV are also treated as traps in case
3130 a breakpoint is inserted at the current PC. If this target does
3131 not support internal breakpoints at all, we also report the
3132 SIGTRAP without further processing; it's of no concern to us. */
3134 = (supports_breakpoints ()
3135 && (WSTOPSIG (w
) == SIGTRAP
3136 || ((WSTOPSIG (w
) == SIGILL
3137 || WSTOPSIG (w
) == SIGSEGV
)
3138 && (*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))));
3140 if (maybe_internal_trap
)
3142 /* Handle anything that requires bookkeeping before deciding to
3143 report the event or continue waiting. */
3145 /* First check if we can explain the SIGTRAP with an internal
3146 breakpoint, or if we should possibly report the event to GDB.
3147 Do this before anything that may remove or insert a
3149 bp_explains_trap
= breakpoint_inserted_here (event_child
->stop_pc
);
3151 /* We have a SIGTRAP, possibly a step-over dance has just
3152 finished. If so, tweak the state machine accordingly,
3153 reinsert breakpoints and delete any reinsert (software
3154 single-step) breakpoints. */
3155 step_over_finished
= finish_step_over (event_child
);
3157 /* Now invoke the callbacks of any internal breakpoints there. */
3158 check_breakpoints (event_child
->stop_pc
);
3160 /* Handle tracepoint data collecting. This may overflow the
3161 trace buffer, and cause a tracing stop, removing
3163 trace_event
= handle_tracepoints (event_child
);
3165 if (bp_explains_trap
)
3167 /* If we stepped or ran into an internal breakpoint, we've
3168 already handled it. So next time we resume (from this
3169 PC), we should step over it. */
3171 debug_printf ("Hit a gdbserver breakpoint.\n");
3173 if (breakpoint_here (event_child
->stop_pc
))
3174 event_child
->need_step_over
= 1;
3179 /* We have some other signal, possibly a step-over dance was in
3180 progress, and it should be cancelled too. */
3181 step_over_finished
= finish_step_over (event_child
);
3184 /* We have all the data we need. Either report the event to GDB, or
3185 resume threads and keep waiting for more. */
3187 /* If we're collecting a fast tracepoint, finish the collection and
3188 move out of the jump pad before delivering a signal. See
3189 linux_stabilize_threads. */
3192 && WSTOPSIG (w
) != SIGTRAP
3193 && supports_fast_tracepoints ()
3194 && agent_loaded_p ())
3197 debug_printf ("Got signal %d for LWP %ld. Check if we need "
3198 "to defer or adjust it.\n",
3199 WSTOPSIG (w
), lwpid_of (current_thread
));
3201 /* Allow debugging the jump pad itself. */
3202 if (current_thread
->last_resume_kind
!= resume_step
3203 && maybe_move_out_of_jump_pad (event_child
, &w
))
3205 enqueue_one_deferred_signal (event_child
, &w
);
3208 debug_printf ("Signal %d for LWP %ld deferred (in jump pad)\n",
3209 WSTOPSIG (w
), lwpid_of (current_thread
));
3211 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
3213 return ignore_event (ourstatus
);
3217 if (event_child
->collecting_fast_tracepoint
)
3220 debug_printf ("LWP %ld was trying to move out of the jump pad (%d). "
3221 "Check if we're already there.\n",
3222 lwpid_of (current_thread
),
3223 event_child
->collecting_fast_tracepoint
);
3227 event_child
->collecting_fast_tracepoint
3228 = linux_fast_tracepoint_collecting (event_child
, NULL
);
3230 if (event_child
->collecting_fast_tracepoint
!= 1)
3232 /* No longer need this breakpoint. */
3233 if (event_child
->exit_jump_pad_bkpt
!= NULL
)
3236 debug_printf ("No longer need exit-jump-pad bkpt; removing it."
3237 "stopping all threads momentarily.\n");
3239 /* Other running threads could hit this breakpoint.
3240 We don't handle moribund locations like GDB does,
3241 instead we always pause all threads when removing
3242 breakpoints, so that any step-over or
3243 decr_pc_after_break adjustment is always taken
3244 care of while the breakpoint is still
3246 stop_all_lwps (1, event_child
);
3248 delete_breakpoint (event_child
->exit_jump_pad_bkpt
);
3249 event_child
->exit_jump_pad_bkpt
= NULL
;
3251 unstop_all_lwps (1, event_child
);
3253 gdb_assert (event_child
->suspended
>= 0);
3257 if (event_child
->collecting_fast_tracepoint
== 0)
3260 debug_printf ("fast tracepoint finished "
3261 "collecting successfully.\n");
3263 /* We may have a deferred signal to report. */
3264 if (dequeue_one_deferred_signal (event_child
, &w
))
3267 debug_printf ("dequeued one signal.\n");
3272 debug_printf ("no deferred signals.\n");
3274 if (stabilizing_threads
)
3276 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
3277 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
3281 debug_printf ("linux_wait_1 ret = %s, stopped "
3282 "while stabilizing threads\n",
3283 target_pid_to_str (ptid_of (current_thread
)));
3287 return ptid_of (current_thread
);
3293 /* Check whether GDB would be interested in this event. */
3295 /* If GDB is not interested in this signal, don't stop other
3296 threads, and don't report it to GDB. Just resume the inferior
3297 right away. We do this for threading-related signals as well as
3298 any that GDB specifically requested we ignore. But never ignore
3299 SIGSTOP if we sent it ourselves, and do not ignore signals when
3300 stepping - they may require special handling to skip the signal
3301 handler. Also never ignore signals that could be caused by a
3303 /* FIXME drow/2002-06-09: Get signal numbers from the inferior's
3306 && current_thread
->last_resume_kind
!= resume_step
3308 #if defined (USE_THREAD_DB) && !defined (__ANDROID__)
3309 (current_process ()->priv
->thread_db
!= NULL
3310 && (WSTOPSIG (w
) == __SIGRTMIN
3311 || WSTOPSIG (w
) == __SIGRTMIN
+ 1))
3314 (pass_signals
[gdb_signal_from_host (WSTOPSIG (w
))]
3315 && !(WSTOPSIG (w
) == SIGSTOP
3316 && current_thread
->last_resume_kind
== resume_stop
)
3317 && !linux_wstatus_maybe_breakpoint (w
))))
3319 siginfo_t info
, *info_p
;
3322 debug_printf ("Ignored signal %d for LWP %ld.\n",
3323 WSTOPSIG (w
), lwpid_of (current_thread
));
3325 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
3326 (PTRACE_TYPE_ARG3
) 0, &info
) == 0)
3331 if (step_over_finished
)
3333 /* We cancelled this thread's step-over above. We still
3334 need to unsuspend all other LWPs, and set them back
3335 running again while the signal handler runs. */
3336 unsuspend_all_lwps (event_child
);
3338 /* Enqueue the pending signal info so that proceed_all_lwps
3340 enqueue_pending_signal (event_child
, WSTOPSIG (w
), info_p
);
3342 proceed_all_lwps ();
3346 linux_resume_one_lwp (event_child
, event_child
->stepping
,
3347 WSTOPSIG (w
), info_p
);
3349 return ignore_event (ourstatus
);
3352 /* Note that all addresses are always "out of the step range" when
3353 there's no range to begin with. */
3354 in_step_range
= lwp_in_step_range (event_child
);
3356 /* If GDB wanted this thread to single step, and the thread is out
3357 of the step range, we always want to report the SIGTRAP, and let
3358 GDB handle it. Watchpoints should always be reported. So should
3359 signals we can't explain. A SIGTRAP we can't explain could be a
3360 GDB breakpoint --- we may or not support Z0 breakpoints. If we
3361 do, we're be able to handle GDB breakpoints on top of internal
3362 breakpoints, by handling the internal breakpoint and still
3363 reporting the event to GDB. If we don't, we're out of luck, GDB
3364 won't see the breakpoint hit. If we see a single-step event but
3365 the thread should be continuing, don't pass the trap to gdb.
3366 That indicates that we had previously finished a single-step but
3367 left the single-step pending -- see
3368 complete_ongoing_step_over. */
3369 report_to_gdb
= (!maybe_internal_trap
3370 || (current_thread
->last_resume_kind
== resume_step
3372 || event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
3374 && !bp_explains_trap
3376 && !step_over_finished
3377 && !(current_thread
->last_resume_kind
== resume_continue
3378 && event_child
->stop_reason
== TARGET_STOPPED_BY_SINGLE_STEP
))
3379 || (gdb_breakpoint_here (event_child
->stop_pc
)
3380 && gdb_condition_true_at_breakpoint (event_child
->stop_pc
)
3381 && gdb_no_commands_at_breakpoint (event_child
->stop_pc
))
3382 || event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
);
3384 run_breakpoint_commands (event_child
->stop_pc
);
3386 /* We found no reason GDB would want us to stop. We either hit one
3387 of our own breakpoints, or finished an internal step GDB
3388 shouldn't know about. */
3393 if (bp_explains_trap
)
3394 debug_printf ("Hit a gdbserver breakpoint.\n");
3395 if (step_over_finished
)
3396 debug_printf ("Step-over finished.\n");
3398 debug_printf ("Tracepoint event.\n");
3399 if (lwp_in_step_range (event_child
))
3400 debug_printf ("Range stepping pc 0x%s [0x%s, 0x%s).\n",
3401 paddress (event_child
->stop_pc
),
3402 paddress (event_child
->step_range_start
),
3403 paddress (event_child
->step_range_end
));
3406 /* We're not reporting this breakpoint to GDB, so apply the
3407 decr_pc_after_break adjustment to the inferior's regcache
3410 if (the_low_target
.set_pc
!= NULL
)
3412 struct regcache
*regcache
3413 = get_thread_regcache (current_thread
, 1);
3414 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
3417 /* We may have finished stepping over a breakpoint. If so,
3418 we've stopped and suspended all LWPs momentarily except the
3419 stepping one. This is where we resume them all again. We're
3420 going to keep waiting, so use proceed, which handles stepping
3421 over the next breakpoint. */
3423 debug_printf ("proceeding all threads.\n");
3425 if (step_over_finished
)
3426 unsuspend_all_lwps (event_child
);
3428 proceed_all_lwps ();
3429 return ignore_event (ourstatus
);
3434 if (event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
3438 str
= target_waitstatus_to_string (&event_child
->waitstatus
);
3439 debug_printf ("LWP %ld: extended event with waitstatus %s\n",
3440 lwpid_of (get_lwp_thread (event_child
)), str
);
3443 if (current_thread
->last_resume_kind
== resume_step
)
3445 if (event_child
->step_range_start
== event_child
->step_range_end
)
3446 debug_printf ("GDB wanted to single-step, reporting event.\n");
3447 else if (!lwp_in_step_range (event_child
))
3448 debug_printf ("Out of step range, reporting event.\n");
3450 if (event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
)
3451 debug_printf ("Stopped by watchpoint.\n");
3452 else if (gdb_breakpoint_here (event_child
->stop_pc
))
3453 debug_printf ("Stopped by GDB breakpoint.\n");
3455 debug_printf ("Hit a non-gdbserver trap event.\n");
3458 /* Alright, we're going to report a stop. */
3460 if (!stabilizing_threads
)
3462 /* In all-stop, stop all threads. */
3464 stop_all_lwps (0, NULL
);
3466 /* If we're not waiting for a specific LWP, choose an event LWP
3467 from among those that have had events. Giving equal priority
3468 to all LWPs that have had events helps prevent
3470 if (ptid_equal (ptid
, minus_one_ptid
))
3472 event_child
->status_pending_p
= 1;
3473 event_child
->status_pending
= w
;
3475 select_event_lwp (&event_child
);
3477 /* current_thread and event_child must stay in sync. */
3478 current_thread
= get_lwp_thread (event_child
);
3480 event_child
->status_pending_p
= 0;
3481 w
= event_child
->status_pending
;
3484 if (step_over_finished
)
3488 /* If we were doing a step-over, all other threads but
3489 the stepping one had been paused in start_step_over,
3490 with their suspend counts incremented. We don't want
3491 to do a full unstop/unpause, because we're in
3492 all-stop mode (so we want threads stopped), but we
3493 still need to unsuspend the other threads, to
3494 decrement their `suspended' count back. */
3495 unsuspend_all_lwps (event_child
);
3499 /* If we just finished a step-over, then all threads had
3500 been momentarily paused. In all-stop, that's fine,
3501 we want threads stopped by now anyway. In non-stop,
3502 we need to re-resume threads that GDB wanted to be
3504 unstop_all_lwps (1, event_child
);
3508 /* Stabilize threads (move out of jump pads). */
3510 stabilize_threads ();
3514 /* If we just finished a step-over, then all threads had been
3515 momentarily paused. In all-stop, that's fine, we want
3516 threads stopped by now anyway. In non-stop, we need to
3517 re-resume threads that GDB wanted to be running. */
3518 if (step_over_finished
)
3519 unstop_all_lwps (1, event_child
);
3522 if (event_child
->waitstatus
.kind
!= TARGET_WAITKIND_IGNORE
)
3524 /* If the reported event is an exit, fork, vfork or exec, let
3526 *ourstatus
= event_child
->waitstatus
;
3527 /* Clear the event lwp's waitstatus since we handled it already. */
3528 event_child
->waitstatus
.kind
= TARGET_WAITKIND_IGNORE
;
3531 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
3533 /* Now that we've selected our final event LWP, un-adjust its PC if
3534 it was a software breakpoint, and the client doesn't know we can
3535 adjust the breakpoint ourselves. */
3536 if (event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3537 && !swbreak_feature
)
3539 int decr_pc
= the_low_target
.decr_pc_after_break
;
3543 struct regcache
*regcache
3544 = get_thread_regcache (current_thread
, 1);
3545 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
+ decr_pc
);
3549 if (current_thread
->last_resume_kind
== resume_stop
3550 && WSTOPSIG (w
) == SIGSTOP
)
3552 /* A thread that has been requested to stop by GDB with vCont;t,
3553 and it stopped cleanly, so report as SIG0. The use of
3554 SIGSTOP is an implementation detail. */
3555 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
3557 else if (current_thread
->last_resume_kind
== resume_stop
3558 && WSTOPSIG (w
) != SIGSTOP
)
3560 /* A thread that has been requested to stop by GDB with vCont;t,
3561 but, it stopped for other reasons. */
3562 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
3564 else if (ourstatus
->kind
== TARGET_WAITKIND_STOPPED
)
3566 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
3569 gdb_assert (ptid_equal (step_over_bkpt
, null_ptid
));
3573 debug_printf ("linux_wait_1 ret = %s, %d, %d\n",
3574 target_pid_to_str (ptid_of (current_thread
)),
3575 ourstatus
->kind
, ourstatus
->value
.sig
);
3579 if (ourstatus
->kind
== TARGET_WAITKIND_EXITED
)
3580 return filter_exit_event (event_child
, ourstatus
);
3582 return ptid_of (current_thread
);
3585 /* Get rid of any pending event in the pipe. */
3587 async_file_flush (void)
3593 ret
= read (linux_event_pipe
[0], &buf
, 1);
3594 while (ret
>= 0 || (ret
== -1 && errno
== EINTR
));
3597 /* Put something in the pipe, so the event loop wakes up. */
3599 async_file_mark (void)
3603 async_file_flush ();
3606 ret
= write (linux_event_pipe
[1], "+", 1);
3607 while (ret
== 0 || (ret
== -1 && errno
== EINTR
));
3609 /* Ignore EAGAIN. If the pipe is full, the event loop will already
3610 be awakened anyway. */
3614 linux_wait (ptid_t ptid
,
3615 struct target_waitstatus
*ourstatus
, int target_options
)
3619 /* Flush the async file first. */
3620 if (target_is_async_p ())
3621 async_file_flush ();
3625 event_ptid
= linux_wait_1 (ptid
, ourstatus
, target_options
);
3627 while ((target_options
& TARGET_WNOHANG
) == 0
3628 && ptid_equal (event_ptid
, null_ptid
)
3629 && ourstatus
->kind
== TARGET_WAITKIND_IGNORE
);
3631 /* If at least one stop was reported, there may be more. A single
3632 SIGCHLD can signal more than one child stop. */
3633 if (target_is_async_p ()
3634 && (target_options
& TARGET_WNOHANG
) != 0
3635 && !ptid_equal (event_ptid
, null_ptid
))
3641 /* Send a signal to an LWP. */
3644 kill_lwp (unsigned long lwpid
, int signo
)
3646 /* Use tkill, if possible, in case we are using nptl threads. If tkill
3647 fails, then we are not using nptl threads and we should be using kill. */
3651 static int tkill_failed
;
3658 ret
= syscall (__NR_tkill
, lwpid
, signo
);
3659 if (errno
!= ENOSYS
)
3666 return kill (lwpid
, signo
);
3670 linux_stop_lwp (struct lwp_info
*lwp
)
3676 send_sigstop (struct lwp_info
*lwp
)
3680 pid
= lwpid_of (get_lwp_thread (lwp
));
3682 /* If we already have a pending stop signal for this process, don't
3684 if (lwp
->stop_expected
)
3687 debug_printf ("Have pending sigstop for lwp %d\n", pid
);
3693 debug_printf ("Sending sigstop to lwp %d\n", pid
);
3695 lwp
->stop_expected
= 1;
3696 kill_lwp (pid
, SIGSTOP
);
3700 send_sigstop_callback (struct inferior_list_entry
*entry
, void *except
)
3702 struct thread_info
*thread
= (struct thread_info
*) entry
;
3703 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3705 /* Ignore EXCEPT. */
3716 /* Increment the suspend count of an LWP, and stop it, if not stopped
3719 suspend_and_send_sigstop_callback (struct inferior_list_entry
*entry
,
3722 struct thread_info
*thread
= (struct thread_info
*) entry
;
3723 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3725 /* Ignore EXCEPT. */
3729 lwp_suspended_inc (lwp
);
3731 return send_sigstop_callback (entry
, except
);
3735 mark_lwp_dead (struct lwp_info
*lwp
, int wstat
)
3737 /* Store the exit status for later. */
3738 lwp
->status_pending_p
= 1;
3739 lwp
->status_pending
= wstat
;
3741 /* Store in waitstatus as well, as there's nothing else to process
3743 if (WIFEXITED (wstat
))
3745 lwp
->waitstatus
.kind
= TARGET_WAITKIND_EXITED
;
3746 lwp
->waitstatus
.value
.integer
= WEXITSTATUS (wstat
);
3748 else if (WIFSIGNALED (wstat
))
3750 lwp
->waitstatus
.kind
= TARGET_WAITKIND_SIGNALLED
;
3751 lwp
->waitstatus
.value
.sig
= gdb_signal_from_host (WTERMSIG (wstat
));
3754 /* Prevent trying to stop it. */
3757 /* No further stops are expected from a dead lwp. */
3758 lwp
->stop_expected
= 0;
3761 /* Return true if LWP has exited already, and has a pending exit event
3762 to report to GDB. */
3765 lwp_is_marked_dead (struct lwp_info
*lwp
)
3767 return (lwp
->status_pending_p
3768 && (WIFEXITED (lwp
->status_pending
)
3769 || WIFSIGNALED (lwp
->status_pending
)));
3772 /* Wait for all children to stop for the SIGSTOPs we just queued. */
3775 wait_for_sigstop (void)
3777 struct thread_info
*saved_thread
;
3782 saved_thread
= current_thread
;
3783 if (saved_thread
!= NULL
)
3784 saved_tid
= saved_thread
->entry
.id
;
3786 saved_tid
= null_ptid
; /* avoid bogus unused warning */
3789 debug_printf ("wait_for_sigstop: pulling events\n");
3791 /* Passing NULL_PTID as filter indicates we want all events to be
3792 left pending. Eventually this returns when there are no
3793 unwaited-for children left. */
3794 ret
= linux_wait_for_event_filtered (minus_one_ptid
, null_ptid
,
3796 gdb_assert (ret
== -1);
3798 if (saved_thread
== NULL
|| linux_thread_alive (saved_tid
))
3799 current_thread
= saved_thread
;
3803 debug_printf ("Previously current thread died.\n");
3805 /* We can't change the current inferior behind GDB's back,
3806 otherwise, a subsequent command may apply to the wrong
3808 current_thread
= NULL
;
3812 /* Returns true if LWP ENTRY is stopped in a jump pad, and we can't
3813 move it out, because we need to report the stop event to GDB. For
3814 example, if the user puts a breakpoint in the jump pad, it's
3815 because she wants to debug it. */
3818 stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
, void *data
)
3820 struct thread_info
*thread
= (struct thread_info
*) entry
;
3821 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3823 if (lwp
->suspended
!= 0)
3825 internal_error (__FILE__
, __LINE__
,
3826 "LWP %ld is suspended, suspended=%d\n",
3827 lwpid_of (thread
), lwp
->suspended
);
3829 gdb_assert (lwp
->stopped
);
3831 /* Allow debugging the jump pad, gdb_collect, etc.. */
3832 return (supports_fast_tracepoints ()
3833 && agent_loaded_p ()
3834 && (gdb_breakpoint_here (lwp
->stop_pc
)
3835 || lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
3836 || thread
->last_resume_kind
== resume_step
)
3837 && linux_fast_tracepoint_collecting (lwp
, NULL
));
3841 move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
)
3843 struct thread_info
*thread
= (struct thread_info
*) entry
;
3844 struct thread_info
*saved_thread
;
3845 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3848 if (lwp
->suspended
!= 0)
3850 internal_error (__FILE__
, __LINE__
,
3851 "LWP %ld is suspended, suspended=%d\n",
3852 lwpid_of (thread
), lwp
->suspended
);
3854 gdb_assert (lwp
->stopped
);
3856 /* For gdb_breakpoint_here. */
3857 saved_thread
= current_thread
;
3858 current_thread
= thread
;
3860 wstat
= lwp
->status_pending_p
? &lwp
->status_pending
: NULL
;
3862 /* Allow debugging the jump pad, gdb_collect, etc. */
3863 if (!gdb_breakpoint_here (lwp
->stop_pc
)
3864 && lwp
->stop_reason
!= TARGET_STOPPED_BY_WATCHPOINT
3865 && thread
->last_resume_kind
!= resume_step
3866 && maybe_move_out_of_jump_pad (lwp
, wstat
))
3869 debug_printf ("LWP %ld needs stabilizing (in jump pad)\n",
3874 lwp
->status_pending_p
= 0;
3875 enqueue_one_deferred_signal (lwp
, wstat
);
3878 debug_printf ("Signal %d for LWP %ld deferred "
3880 WSTOPSIG (*wstat
), lwpid_of (thread
));
3883 linux_resume_one_lwp (lwp
, 0, 0, NULL
);
3886 lwp_suspended_inc (lwp
);
3888 current_thread
= saved_thread
;
3892 lwp_running (struct inferior_list_entry
*entry
, void *data
)
3894 struct thread_info
*thread
= (struct thread_info
*) entry
;
3895 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3897 if (lwp_is_marked_dead (lwp
))
3904 /* Stop all lwps that aren't stopped yet, except EXCEPT, if not NULL.
3905 If SUSPEND, then also increase the suspend count of every LWP,
3909 stop_all_lwps (int suspend
, struct lwp_info
*except
)
3911 /* Should not be called recursively. */
3912 gdb_assert (stopping_threads
== NOT_STOPPING_THREADS
);
3917 debug_printf ("stop_all_lwps (%s, except=%s)\n",
3918 suspend
? "stop-and-suspend" : "stop",
3920 ? target_pid_to_str (ptid_of (get_lwp_thread (except
)))
3924 stopping_threads
= (suspend
3925 ? STOPPING_AND_SUSPENDING_THREADS
3926 : STOPPING_THREADS
);
3929 find_inferior (&all_threads
, suspend_and_send_sigstop_callback
, except
);
3931 find_inferior (&all_threads
, send_sigstop_callback
, except
);
3932 wait_for_sigstop ();
3933 stopping_threads
= NOT_STOPPING_THREADS
;
3937 debug_printf ("stop_all_lwps done, setting stopping_threads "
3938 "back to !stopping\n");
3943 /* Enqueue one signal in the chain of signals which need to be
3944 delivered to this process on next resume. */
3947 enqueue_pending_signal (struct lwp_info
*lwp
, int signal
, siginfo_t
*info
)
3949 struct pending_signals
*p_sig
= XNEW (struct pending_signals
);
3951 p_sig
->prev
= lwp
->pending_signals
;
3952 p_sig
->signal
= signal
;
3954 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
3956 memcpy (&p_sig
->info
, info
, sizeof (siginfo_t
));
3957 lwp
->pending_signals
= p_sig
;
3960 /* Resume execution of LWP. If STEP is nonzero, single-step it. If
3961 SIGNAL is nonzero, give it that signal. */
3964 linux_resume_one_lwp_throw (struct lwp_info
*lwp
,
3965 int step
, int signal
, siginfo_t
*info
)
3967 struct thread_info
*thread
= get_lwp_thread (lwp
);
3968 struct thread_info
*saved_thread
;
3969 int fast_tp_collecting
;
3970 struct process_info
*proc
= get_thread_process (thread
);
3972 /* Note that target description may not be initialised
3973 (proc->tdesc == NULL) at this point because the program hasn't
3974 stopped at the first instruction yet. It means GDBserver skips
3975 the extra traps from the wrapper program (see option --wrapper).
3976 Code in this function that requires register access should be
3977 guarded by proc->tdesc == NULL or something else. */
3979 if (lwp
->stopped
== 0)
3982 gdb_assert (lwp
->waitstatus
.kind
== TARGET_WAITKIND_IGNORE
);
3984 fast_tp_collecting
= lwp
->collecting_fast_tracepoint
;
3986 gdb_assert (!stabilizing_threads
|| fast_tp_collecting
);
3988 /* Cancel actions that rely on GDB not changing the PC (e.g., the
3989 user used the "jump" command, or "set $pc = foo"). */
3990 if (thread
->while_stepping
!= NULL
&& lwp
->stop_pc
!= get_pc (lwp
))
3992 /* Collecting 'while-stepping' actions doesn't make sense
3994 release_while_stepping_state_list (thread
);
3997 /* If we have pending signals or status, and a new signal, enqueue the
3998 signal. Also enqueue the signal if we are waiting to reinsert a
3999 breakpoint; it will be picked up again below. */
4001 && (lwp
->status_pending_p
4002 || lwp
->pending_signals
!= NULL
4003 || lwp
->bp_reinsert
!= 0
4004 || fast_tp_collecting
))
4006 struct pending_signals
*p_sig
= XNEW (struct pending_signals
);
4008 p_sig
->prev
= lwp
->pending_signals
;
4009 p_sig
->signal
= signal
;
4011 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
4013 memcpy (&p_sig
->info
, info
, sizeof (siginfo_t
));
4014 lwp
->pending_signals
= p_sig
;
4017 if (lwp
->status_pending_p
)
4020 debug_printf ("Not resuming lwp %ld (%s, signal %d, stop %s);"
4021 " has pending status\n",
4022 lwpid_of (thread
), step
? "step" : "continue", signal
,
4023 lwp
->stop_expected
? "expected" : "not expected");
4027 saved_thread
= current_thread
;
4028 current_thread
= thread
;
4031 debug_printf ("Resuming lwp %ld (%s, signal %d, stop %s)\n",
4032 lwpid_of (thread
), step
? "step" : "continue", signal
,
4033 lwp
->stop_expected
? "expected" : "not expected");
4035 /* This bit needs some thinking about. If we get a signal that
4036 we must report while a single-step reinsert is still pending,
4037 we often end up resuming the thread. It might be better to
4038 (ew) allow a stack of pending events; then we could be sure that
4039 the reinsert happened right away and not lose any signals.
4041 Making this stack would also shrink the window in which breakpoints are
4042 uninserted (see comment in linux_wait_for_lwp) but not enough for
4043 complete correctness, so it won't solve that problem. It may be
4044 worthwhile just to solve this one, however. */
4045 if (lwp
->bp_reinsert
!= 0)
4048 debug_printf (" pending reinsert at 0x%s\n",
4049 paddress (lwp
->bp_reinsert
));
4051 if (can_hardware_single_step ())
4053 if (fast_tp_collecting
== 0)
4056 fprintf (stderr
, "BAD - reinserting but not stepping.\n");
4058 fprintf (stderr
, "BAD - reinserting and suspended(%d).\n",
4065 /* Postpone any pending signal. It was enqueued above. */
4069 if (fast_tp_collecting
== 1)
4072 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
4073 " (exit-jump-pad-bkpt)\n",
4076 /* Postpone any pending signal. It was enqueued above. */
4079 else if (fast_tp_collecting
== 2)
4082 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
4083 " single-stepping\n",
4086 if (can_hardware_single_step ())
4090 internal_error (__FILE__
, __LINE__
,
4091 "moving out of jump pad single-stepping"
4092 " not implemented on this target");
4095 /* Postpone any pending signal. It was enqueued above. */
4099 /* If we have while-stepping actions in this thread set it stepping.
4100 If we have a signal to deliver, it may or may not be set to
4101 SIG_IGN, we don't know. Assume so, and allow collecting
4102 while-stepping into a signal handler. A possible smart thing to
4103 do would be to set an internal breakpoint at the signal return
4104 address, continue, and carry on catching this while-stepping
4105 action only when that breakpoint is hit. A future
4107 if (thread
->while_stepping
!= NULL
4108 && can_hardware_single_step ())
4111 debug_printf ("lwp %ld has a while-stepping action -> forcing step.\n",
4116 if (proc
->tdesc
!= NULL
&& the_low_target
.get_pc
!= NULL
)
4118 struct regcache
*regcache
= get_thread_regcache (current_thread
, 1);
4120 lwp
->stop_pc
= (*the_low_target
.get_pc
) (regcache
);
4124 debug_printf (" %s from pc 0x%lx\n", step
? "step" : "continue",
4125 (long) lwp
->stop_pc
);
4129 /* If we have pending signals, consume one unless we are trying to
4130 reinsert a breakpoint or we're trying to finish a fast tracepoint
4132 if (lwp
->pending_signals
!= NULL
4133 && lwp
->bp_reinsert
== 0
4134 && fast_tp_collecting
== 0)
4136 struct pending_signals
**p_sig
;
4138 p_sig
= &lwp
->pending_signals
;
4139 while ((*p_sig
)->prev
!= NULL
)
4140 p_sig
= &(*p_sig
)->prev
;
4142 signal
= (*p_sig
)->signal
;
4143 if ((*p_sig
)->info
.si_signo
!= 0)
4144 ptrace (PTRACE_SETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
4151 if (the_low_target
.prepare_to_resume
!= NULL
)
4152 the_low_target
.prepare_to_resume (lwp
);
4154 regcache_invalidate_thread (thread
);
4156 lwp
->stepping
= step
;
4157 ptrace (step
? PTRACE_SINGLESTEP
: PTRACE_CONT
, lwpid_of (thread
),
4158 (PTRACE_TYPE_ARG3
) 0,
4159 /* Coerce to a uintptr_t first to avoid potential gcc warning
4160 of coercing an 8 byte integer to a 4 byte pointer. */
4161 (PTRACE_TYPE_ARG4
) (uintptr_t) signal
);
4163 current_thread
= saved_thread
;
4165 perror_with_name ("resuming thread");
4167 /* Successfully resumed. Clear state that no longer makes sense,
4168 and mark the LWP as running. Must not do this before resuming
4169 otherwise if that fails other code will be confused. E.g., we'd
4170 later try to stop the LWP and hang forever waiting for a stop
4171 status. Note that we must not throw after this is cleared,
4172 otherwise handle_zombie_lwp_error would get confused. */
4174 lwp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
4177 /* Called when we try to resume a stopped LWP and that errors out. If
4178 the LWP is no longer in ptrace-stopped state (meaning it's zombie,
4179 or about to become), discard the error, clear any pending status
4180 the LWP may have, and return true (we'll collect the exit status
4181 soon enough). Otherwise, return false. */
4184 check_ptrace_stopped_lwp_gone (struct lwp_info
*lp
)
4186 struct thread_info
*thread
= get_lwp_thread (lp
);
4188 /* If we get an error after resuming the LWP successfully, we'd
4189 confuse !T state for the LWP being gone. */
4190 gdb_assert (lp
->stopped
);
4192 /* We can't just check whether the LWP is in 'Z (Zombie)' state,
4193 because even if ptrace failed with ESRCH, the tracee may be "not
4194 yet fully dead", but already refusing ptrace requests. In that
4195 case the tracee has 'R (Running)' state for a little bit
4196 (observed in Linux 3.18). See also the note on ESRCH in the
4197 ptrace(2) man page. Instead, check whether the LWP has any state
4198 other than ptrace-stopped. */
4200 /* Don't assume anything if /proc/PID/status can't be read. */
4201 if (linux_proc_pid_is_trace_stopped_nowarn (lwpid_of (thread
)) == 0)
4203 lp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
4204 lp
->status_pending_p
= 0;
4210 /* Like linux_resume_one_lwp_throw, but no error is thrown if the LWP
4211 disappears while we try to resume it. */
4214 linux_resume_one_lwp (struct lwp_info
*lwp
,
4215 int step
, int signal
, siginfo_t
*info
)
4219 linux_resume_one_lwp_throw (lwp
, step
, signal
, info
);
4221 CATCH (ex
, RETURN_MASK_ERROR
)
4223 if (!check_ptrace_stopped_lwp_gone (lwp
))
4224 throw_exception (ex
);
4229 struct thread_resume_array
4231 struct thread_resume
*resume
;
4235 /* This function is called once per thread via find_inferior.
4236 ARG is a pointer to a thread_resume_array struct.
4237 We look up the thread specified by ENTRY in ARG, and mark the thread
4238 with a pointer to the appropriate resume request.
4240 This algorithm is O(threads * resume elements), but resume elements
4241 is small (and will remain small at least until GDB supports thread
4245 linux_set_resume_request (struct inferior_list_entry
*entry
, void *arg
)
4247 struct thread_info
*thread
= (struct thread_info
*) entry
;
4248 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4250 struct thread_resume_array
*r
;
4252 r
= (struct thread_resume_array
*) arg
;
4254 for (ndx
= 0; ndx
< r
->n
; ndx
++)
4256 ptid_t ptid
= r
->resume
[ndx
].thread
;
4257 if (ptid_equal (ptid
, minus_one_ptid
)
4258 || ptid_equal (ptid
, entry
->id
)
4259 /* Handle both 'pPID' and 'pPID.-1' as meaning 'all threads
4261 || (ptid_get_pid (ptid
) == pid_of (thread
)
4262 && (ptid_is_pid (ptid
)
4263 || ptid_get_lwp (ptid
) == -1)))
4265 if (r
->resume
[ndx
].kind
== resume_stop
4266 && thread
->last_resume_kind
== resume_stop
)
4269 debug_printf ("already %s LWP %ld at GDB's request\n",
4270 (thread
->last_status
.kind
4271 == TARGET_WAITKIND_STOPPED
)
4279 lwp
->resume
= &r
->resume
[ndx
];
4280 thread
->last_resume_kind
= lwp
->resume
->kind
;
4282 lwp
->step_range_start
= lwp
->resume
->step_range_start
;
4283 lwp
->step_range_end
= lwp
->resume
->step_range_end
;
4285 /* If we had a deferred signal to report, dequeue one now.
4286 This can happen if LWP gets more than one signal while
4287 trying to get out of a jump pad. */
4289 && !lwp
->status_pending_p
4290 && dequeue_one_deferred_signal (lwp
, &lwp
->status_pending
))
4292 lwp
->status_pending_p
= 1;
4295 debug_printf ("Dequeueing deferred signal %d for LWP %ld, "
4296 "leaving status pending.\n",
4297 WSTOPSIG (lwp
->status_pending
),
4305 /* No resume action for this thread. */
4311 /* find_inferior callback for linux_resume.
4312 Set *FLAG_P if this lwp has an interesting status pending. */
4315 resume_status_pending_p (struct inferior_list_entry
*entry
, void *flag_p
)
4317 struct thread_info
*thread
= (struct thread_info
*) entry
;
4318 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4320 /* LWPs which will not be resumed are not interesting, because
4321 we might not wait for them next time through linux_wait. */
4322 if (lwp
->resume
== NULL
)
4325 if (thread_still_has_status_pending_p (thread
))
4326 * (int *) flag_p
= 1;
4331 /* Return 1 if this lwp that GDB wants running is stopped at an
4332 internal breakpoint that we need to step over. It assumes that any
4333 required STOP_PC adjustment has already been propagated to the
4334 inferior's regcache. */
4337 need_step_over_p (struct inferior_list_entry
*entry
, void *dummy
)
4339 struct thread_info
*thread
= (struct thread_info
*) entry
;
4340 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4341 struct thread_info
*saved_thread
;
4343 struct process_info
*proc
= get_thread_process (thread
);
4345 /* GDBserver is skipping the extra traps from the wrapper program,
4346 don't have to do step over. */
4347 if (proc
->tdesc
== NULL
)
4350 /* LWPs which will not be resumed are not interesting, because we
4351 might not wait for them next time through linux_wait. */
4356 debug_printf ("Need step over [LWP %ld]? Ignoring, not stopped\n",
4361 if (thread
->last_resume_kind
== resume_stop
)
4364 debug_printf ("Need step over [LWP %ld]? Ignoring, should remain"
4370 gdb_assert (lwp
->suspended
>= 0);
4375 debug_printf ("Need step over [LWP %ld]? Ignoring, suspended\n",
4380 if (!lwp
->need_step_over
)
4383 debug_printf ("Need step over [LWP %ld]? No\n", lwpid_of (thread
));
4386 if (lwp
->status_pending_p
)
4389 debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
4395 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
4399 /* If the PC has changed since we stopped, then don't do anything,
4400 and let the breakpoint/tracepoint be hit. This happens if, for
4401 instance, GDB handled the decr_pc_after_break subtraction itself,
4402 GDB is OOL stepping this thread, or the user has issued a "jump"
4403 command, or poked thread's registers herself. */
4404 if (pc
!= lwp
->stop_pc
)
4407 debug_printf ("Need step over [LWP %ld]? Cancelling, PC was changed. "
4408 "Old stop_pc was 0x%s, PC is now 0x%s\n",
4410 paddress (lwp
->stop_pc
), paddress (pc
));
4412 lwp
->need_step_over
= 0;
4416 saved_thread
= current_thread
;
4417 current_thread
= thread
;
4419 /* We can only step over breakpoints we know about. */
4420 if (breakpoint_here (pc
) || fast_tracepoint_jump_here (pc
))
4422 /* Don't step over a breakpoint that GDB expects to hit
4423 though. If the condition is being evaluated on the target's side
4424 and it evaluate to false, step over this breakpoint as well. */
4425 if (gdb_breakpoint_here (pc
)
4426 && gdb_condition_true_at_breakpoint (pc
)
4427 && gdb_no_commands_at_breakpoint (pc
))
4430 debug_printf ("Need step over [LWP %ld]? yes, but found"
4431 " GDB breakpoint at 0x%s; skipping step over\n",
4432 lwpid_of (thread
), paddress (pc
));
4434 current_thread
= saved_thread
;
4440 debug_printf ("Need step over [LWP %ld]? yes, "
4441 "found breakpoint at 0x%s\n",
4442 lwpid_of (thread
), paddress (pc
));
4444 /* We've found an lwp that needs stepping over --- return 1 so
4445 that find_inferior stops looking. */
4446 current_thread
= saved_thread
;
4448 /* If the step over is cancelled, this is set again. */
4449 lwp
->need_step_over
= 0;
4454 current_thread
= saved_thread
;
4457 debug_printf ("Need step over [LWP %ld]? No, no breakpoint found"
4459 lwpid_of (thread
), paddress (pc
));
4464 /* Start a step-over operation on LWP. When LWP stopped at a
4465 breakpoint, to make progress, we need to remove the breakpoint out
4466 of the way. If we let other threads run while we do that, they may
4467 pass by the breakpoint location and miss hitting it. To avoid
4468 that, a step-over momentarily stops all threads while LWP is
4469 single-stepped while the breakpoint is temporarily uninserted from
4470 the inferior. When the single-step finishes, we reinsert the
4471 breakpoint, and let all threads that are supposed to be running,
4474 On targets that don't support hardware single-step, we don't
4475 currently support full software single-stepping. Instead, we only
4476 support stepping over the thread event breakpoint, by asking the
4477 low target where to place a reinsert breakpoint. Since this
4478 routine assumes the breakpoint being stepped over is a thread event
4479 breakpoint, it usually assumes the return address of the current
4480 function is a good enough place to set the reinsert breakpoint. */
4483 start_step_over (struct lwp_info
*lwp
)
4485 struct thread_info
*thread
= get_lwp_thread (lwp
);
4486 struct thread_info
*saved_thread
;
4491 debug_printf ("Starting step-over on LWP %ld. Stopping all threads\n",
4494 stop_all_lwps (1, lwp
);
4496 if (lwp
->suspended
!= 0)
4498 internal_error (__FILE__
, __LINE__
,
4499 "LWP %ld suspended=%d\n", lwpid_of (thread
),
4504 debug_printf ("Done stopping all threads for step-over.\n");
4506 /* Note, we should always reach here with an already adjusted PC,
4507 either by GDB (if we're resuming due to GDB's request), or by our
4508 caller, if we just finished handling an internal breakpoint GDB
4509 shouldn't care about. */
4512 saved_thread
= current_thread
;
4513 current_thread
= thread
;
4515 lwp
->bp_reinsert
= pc
;
4516 uninsert_breakpoints_at (pc
);
4517 uninsert_fast_tracepoint_jumps_at (pc
);
4519 if (can_hardware_single_step ())
4523 else if (can_software_single_step ())
4525 CORE_ADDR raddr
= (*the_low_target
.breakpoint_reinsert_addr
) ();
4526 set_reinsert_breakpoint (raddr
);
4531 internal_error (__FILE__
, __LINE__
,
4532 "stepping is not implemented on this target");
4535 current_thread
= saved_thread
;
4537 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
4539 /* Require next event from this LWP. */
4540 step_over_bkpt
= thread
->entry
.id
;
4544 /* Finish a step-over. Reinsert the breakpoint we had uninserted in
4545 start_step_over, if still there, and delete any reinsert
4546 breakpoints we've set, on non hardware single-step targets. */
4549 finish_step_over (struct lwp_info
*lwp
)
4551 if (lwp
->bp_reinsert
!= 0)
4554 debug_printf ("Finished step over.\n");
4556 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
4557 may be no breakpoint to reinsert there by now. */
4558 reinsert_breakpoints_at (lwp
->bp_reinsert
);
4559 reinsert_fast_tracepoint_jumps_at (lwp
->bp_reinsert
);
4561 lwp
->bp_reinsert
= 0;
4563 /* Delete any software-single-step reinsert breakpoints. No
4564 longer needed. We don't have to worry about other threads
4565 hitting this trap, and later not being able to explain it,
4566 because we were stepping over a breakpoint, and we hold all
4567 threads but LWP stopped while doing that. */
4568 if (!can_hardware_single_step ())
4569 delete_reinsert_breakpoints ();
4571 step_over_bkpt
= null_ptid
;
4578 /* If there's a step over in progress, wait until all threads stop
4579 (that is, until the stepping thread finishes its step), and
4580 unsuspend all lwps. The stepping thread ends with its status
4581 pending, which is processed later when we get back to processing
4585 complete_ongoing_step_over (void)
4587 if (!ptid_equal (step_over_bkpt
, null_ptid
))
4589 struct lwp_info
*lwp
;
4594 debug_printf ("detach: step over in progress, finish it first\n");
4596 /* Passing NULL_PTID as filter indicates we want all events to
4597 be left pending. Eventually this returns when there are no
4598 unwaited-for children left. */
4599 ret
= linux_wait_for_event_filtered (minus_one_ptid
, null_ptid
,
4601 gdb_assert (ret
== -1);
4603 lwp
= find_lwp_pid (step_over_bkpt
);
4605 finish_step_over (lwp
);
4606 step_over_bkpt
= null_ptid
;
4607 unsuspend_all_lwps (lwp
);
4611 /* This function is called once per thread. We check the thread's resume
4612 request, which will tell us whether to resume, step, or leave the thread
4613 stopped; and what signal, if any, it should be sent.
4615 For threads which we aren't explicitly told otherwise, we preserve
4616 the stepping flag; this is used for stepping over gdbserver-placed
4619 If pending_flags was set in any thread, we queue any needed
4620 signals, since we won't actually resume. We already have a pending
4621 event to report, so we don't need to preserve any step requests;
4622 they should be re-issued if necessary. */
4625 linux_resume_one_thread (struct inferior_list_entry
*entry
, void *arg
)
4627 struct thread_info
*thread
= (struct thread_info
*) entry
;
4628 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4630 int leave_all_stopped
= * (int *) arg
;
4633 if (lwp
->resume
== NULL
)
4636 if (lwp
->resume
->kind
== resume_stop
)
4639 debug_printf ("resume_stop request for LWP %ld\n", lwpid_of (thread
));
4644 debug_printf ("stopping LWP %ld\n", lwpid_of (thread
));
4646 /* Stop the thread, and wait for the event asynchronously,
4647 through the event loop. */
4653 debug_printf ("already stopped LWP %ld\n",
4656 /* The LWP may have been stopped in an internal event that
4657 was not meant to be notified back to GDB (e.g., gdbserver
4658 breakpoint), so we should be reporting a stop event in
4661 /* If the thread already has a pending SIGSTOP, this is a
4662 no-op. Otherwise, something later will presumably resume
4663 the thread and this will cause it to cancel any pending
4664 operation, due to last_resume_kind == resume_stop. If
4665 the thread already has a pending status to report, we
4666 will still report it the next time we wait - see
4667 status_pending_p_callback. */
4669 /* If we already have a pending signal to report, then
4670 there's no need to queue a SIGSTOP, as this means we're
4671 midway through moving the LWP out of the jumppad, and we
4672 will report the pending signal as soon as that is
4674 if (lwp
->pending_signals_to_report
== NULL
)
4678 /* For stop requests, we're done. */
4680 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
4684 /* If this thread which is about to be resumed has a pending status,
4685 then don't resume it - we can just report the pending status.
4686 Likewise if it is suspended, because e.g., another thread is
4687 stepping past a breakpoint. Make sure to queue any signals that
4688 would otherwise be sent. In all-stop mode, we do this decision
4689 based on if *any* thread has a pending status. If there's a
4690 thread that needs the step-over-breakpoint dance, then don't
4691 resume any other thread but that particular one. */
4692 leave_pending
= (lwp
->suspended
4693 || lwp
->status_pending_p
4694 || leave_all_stopped
);
4699 debug_printf ("resuming LWP %ld\n", lwpid_of (thread
));
4701 step
= (lwp
->resume
->kind
== resume_step
);
4702 linux_resume_one_lwp (lwp
, step
, lwp
->resume
->sig
, NULL
);
4707 debug_printf ("leaving LWP %ld stopped\n", lwpid_of (thread
));
4709 /* If we have a new signal, enqueue the signal. */
4710 if (lwp
->resume
->sig
!= 0)
4712 struct pending_signals
*p_sig
= XCNEW (struct pending_signals
);
4714 p_sig
->prev
= lwp
->pending_signals
;
4715 p_sig
->signal
= lwp
->resume
->sig
;
4717 /* If this is the same signal we were previously stopped by,
4718 make sure to queue its siginfo. We can ignore the return
4719 value of ptrace; if it fails, we'll skip
4720 PTRACE_SETSIGINFO. */
4721 if (WIFSTOPPED (lwp
->last_status
)
4722 && WSTOPSIG (lwp
->last_status
) == lwp
->resume
->sig
)
4723 ptrace (PTRACE_GETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
4726 lwp
->pending_signals
= p_sig
;
4730 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
4736 linux_resume (struct thread_resume
*resume_info
, size_t n
)
4738 struct thread_resume_array array
= { resume_info
, n
};
4739 struct thread_info
*need_step_over
= NULL
;
4741 int leave_all_stopped
;
4746 debug_printf ("linux_resume:\n");
4749 find_inferior (&all_threads
, linux_set_resume_request
, &array
);
4751 /* If there is a thread which would otherwise be resumed, which has
4752 a pending status, then don't resume any threads - we can just
4753 report the pending status. Make sure to queue any signals that
4754 would otherwise be sent. In non-stop mode, we'll apply this
4755 logic to each thread individually. We consume all pending events
4756 before considering to start a step-over (in all-stop). */
4759 find_inferior (&all_threads
, resume_status_pending_p
, &any_pending
);
4761 /* If there is a thread which would otherwise be resumed, which is
4762 stopped at a breakpoint that needs stepping over, then don't
4763 resume any threads - have it step over the breakpoint with all
4764 other threads stopped, then resume all threads again. Make sure
4765 to queue any signals that would otherwise be delivered or
4767 if (!any_pending
&& supports_breakpoints ())
4769 = (struct thread_info
*) find_inferior (&all_threads
,
4770 need_step_over_p
, NULL
);
4772 leave_all_stopped
= (need_step_over
!= NULL
|| any_pending
);
4776 if (need_step_over
!= NULL
)
4777 debug_printf ("Not resuming all, need step over\n");
4778 else if (any_pending
)
4779 debug_printf ("Not resuming, all-stop and found "
4780 "an LWP with pending status\n");
4782 debug_printf ("Resuming, no pending status or step over needed\n");
4785 /* Even if we're leaving threads stopped, queue all signals we'd
4786 otherwise deliver. */
4787 find_inferior (&all_threads
, linux_resume_one_thread
, &leave_all_stopped
);
4790 start_step_over (get_thread_lwp (need_step_over
));
4794 debug_printf ("linux_resume done\n");
4798 /* We may have events that were pending that can/should be sent to
4799 the client now. Trigger a linux_wait call. */
4800 if (target_is_async_p ())
4804 /* This function is called once per thread. We check the thread's
4805 last resume request, which will tell us whether to resume, step, or
4806 leave the thread stopped. Any signal the client requested to be
4807 delivered has already been enqueued at this point.
4809 If any thread that GDB wants running is stopped at an internal
4810 breakpoint that needs stepping over, we start a step-over operation
4811 on that particular thread, and leave all others stopped. */
4814 proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
4816 struct thread_info
*thread
= (struct thread_info
*) entry
;
4817 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4824 debug_printf ("proceed_one_lwp: lwp %ld\n", lwpid_of (thread
));
4829 debug_printf (" LWP %ld already running\n", lwpid_of (thread
));
4833 if (thread
->last_resume_kind
== resume_stop
4834 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
4837 debug_printf (" client wants LWP to remain %ld stopped\n",
4842 if (lwp
->status_pending_p
)
4845 debug_printf (" LWP %ld has pending status, leaving stopped\n",
4850 gdb_assert (lwp
->suspended
>= 0);
4855 debug_printf (" LWP %ld is suspended\n", lwpid_of (thread
));
4859 if (thread
->last_resume_kind
== resume_stop
4860 && lwp
->pending_signals_to_report
== NULL
4861 && lwp
->collecting_fast_tracepoint
== 0)
4863 /* We haven't reported this LWP as stopped yet (otherwise, the
4864 last_status.kind check above would catch it, and we wouldn't
4865 reach here. This LWP may have been momentarily paused by a
4866 stop_all_lwps call while handling for example, another LWP's
4867 step-over. In that case, the pending expected SIGSTOP signal
4868 that was queued at vCont;t handling time will have already
4869 been consumed by wait_for_sigstop, and so we need to requeue
4870 another one here. Note that if the LWP already has a SIGSTOP
4871 pending, this is a no-op. */
4874 debug_printf ("Client wants LWP %ld to stop. "
4875 "Making sure it has a SIGSTOP pending\n",
4881 if (thread
->last_resume_kind
== resume_step
)
4884 debug_printf (" stepping LWP %ld, client wants it stepping\n",
4888 else if (lwp
->bp_reinsert
!= 0)
4891 debug_printf (" stepping LWP %ld, reinsert set\n",
4898 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
4903 unsuspend_and_proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
4905 struct thread_info
*thread
= (struct thread_info
*) entry
;
4906 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4911 lwp_suspended_decr (lwp
);
4913 return proceed_one_lwp (entry
, except
);
4916 /* When we finish a step-over, set threads running again. If there's
4917 another thread that may need a step-over, now's the time to start
4918 it. Eventually, we'll move all threads past their breakpoints. */
4921 proceed_all_lwps (void)
4923 struct thread_info
*need_step_over
;
4925 /* If there is a thread which would otherwise be resumed, which is
4926 stopped at a breakpoint that needs stepping over, then don't
4927 resume any threads - have it step over the breakpoint with all
4928 other threads stopped, then resume all threads again. */
4930 if (supports_breakpoints ())
4933 = (struct thread_info
*) find_inferior (&all_threads
,
4934 need_step_over_p
, NULL
);
4936 if (need_step_over
!= NULL
)
4939 debug_printf ("proceed_all_lwps: found "
4940 "thread %ld needing a step-over\n",
4941 lwpid_of (need_step_over
));
4943 start_step_over (get_thread_lwp (need_step_over
));
4949 debug_printf ("Proceeding, no step-over needed\n");
4951 find_inferior (&all_threads
, proceed_one_lwp
, NULL
);
4954 /* Stopped LWPs that the client wanted to be running, that don't have
4955 pending statuses, are set to run again, except for EXCEPT, if not
4956 NULL. This undoes a stop_all_lwps call. */
4959 unstop_all_lwps (int unsuspend
, struct lwp_info
*except
)
4965 debug_printf ("unstopping all lwps, except=(LWP %ld)\n",
4966 lwpid_of (get_lwp_thread (except
)));
4968 debug_printf ("unstopping all lwps\n");
4972 find_inferior (&all_threads
, unsuspend_and_proceed_one_lwp
, except
);
4974 find_inferior (&all_threads
, proceed_one_lwp
, except
);
4978 debug_printf ("unstop_all_lwps done\n");
4984 #ifdef HAVE_LINUX_REGSETS
4986 #define use_linux_regsets 1
4988 /* Returns true if REGSET has been disabled. */
4991 regset_disabled (struct regsets_info
*info
, struct regset_info
*regset
)
4993 return (info
->disabled_regsets
!= NULL
4994 && info
->disabled_regsets
[regset
- info
->regsets
]);
4997 /* Disable REGSET. */
5000 disable_regset (struct regsets_info
*info
, struct regset_info
*regset
)
5004 dr_offset
= regset
- info
->regsets
;
5005 if (info
->disabled_regsets
== NULL
)
5006 info
->disabled_regsets
= (char *) xcalloc (1, info
->num_regsets
);
5007 info
->disabled_regsets
[dr_offset
] = 1;
5011 regsets_fetch_inferior_registers (struct regsets_info
*regsets_info
,
5012 struct regcache
*regcache
)
5014 struct regset_info
*regset
;
5015 int saw_general_regs
= 0;
5019 pid
= lwpid_of (current_thread
);
5020 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
5025 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
))
5028 buf
= xmalloc (regset
->size
);
5030 nt_type
= regset
->nt_type
;
5034 iov
.iov_len
= regset
->size
;
5035 data
= (void *) &iov
;
5041 res
= ptrace (regset
->get_request
, pid
,
5042 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5044 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
5050 /* If we get EIO on a regset, do not try it again for
5051 this process mode. */
5052 disable_regset (regsets_info
, regset
);
5054 else if (errno
== ENODATA
)
5056 /* ENODATA may be returned if the regset is currently
5057 not "active". This can happen in normal operation,
5058 so suppress the warning in this case. */
5063 sprintf (s
, "ptrace(regsets_fetch_inferior_registers) PID=%d",
5070 if (regset
->type
== GENERAL_REGS
)
5071 saw_general_regs
= 1;
5072 regset
->store_function (regcache
, buf
);
5076 if (saw_general_regs
)
5083 regsets_store_inferior_registers (struct regsets_info
*regsets_info
,
5084 struct regcache
*regcache
)
5086 struct regset_info
*regset
;
5087 int saw_general_regs
= 0;
5091 pid
= lwpid_of (current_thread
);
5092 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
5097 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
)
5098 || regset
->fill_function
== NULL
)
5101 buf
= xmalloc (regset
->size
);
5103 /* First fill the buffer with the current register set contents,
5104 in case there are any items in the kernel's regset that are
5105 not in gdbserver's regcache. */
5107 nt_type
= regset
->nt_type
;
5111 iov
.iov_len
= regset
->size
;
5112 data
= (void *) &iov
;
5118 res
= ptrace (regset
->get_request
, pid
,
5119 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5121 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
5126 /* Then overlay our cached registers on that. */
5127 regset
->fill_function (regcache
, buf
);
5129 /* Only now do we write the register set. */
5131 res
= ptrace (regset
->set_request
, pid
,
5132 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
5134 res
= ptrace (regset
->set_request
, pid
, data
, nt_type
);
5142 /* If we get EIO on a regset, do not try it again for
5143 this process mode. */
5144 disable_regset (regsets_info
, regset
);
5146 else if (errno
== ESRCH
)
5148 /* At this point, ESRCH should mean the process is
5149 already gone, in which case we simply ignore attempts
5150 to change its registers. See also the related
5151 comment in linux_resume_one_lwp. */
5157 perror ("Warning: ptrace(regsets_store_inferior_registers)");
5160 else if (regset
->type
== GENERAL_REGS
)
5161 saw_general_regs
= 1;
5164 if (saw_general_regs
)
5170 #else /* !HAVE_LINUX_REGSETS */
5172 #define use_linux_regsets 0
5173 #define regsets_fetch_inferior_registers(regsets_info, regcache) 1
5174 #define regsets_store_inferior_registers(regsets_info, regcache) 1
5178 /* Return 1 if register REGNO is supported by one of the regset ptrace
5179 calls or 0 if it has to be transferred individually. */
5182 linux_register_in_regsets (const struct regs_info
*regs_info
, int regno
)
5184 unsigned char mask
= 1 << (regno
% 8);
5185 size_t index
= regno
/ 8;
5187 return (use_linux_regsets
5188 && (regs_info
->regset_bitmap
== NULL
5189 || (regs_info
->regset_bitmap
[index
] & mask
) != 0));
5192 #ifdef HAVE_LINUX_USRREGS
5195 register_addr (const struct usrregs_info
*usrregs
, int regnum
)
5199 if (regnum
< 0 || regnum
>= usrregs
->num_regs
)
5200 error ("Invalid register number %d.", regnum
);
5202 addr
= usrregs
->regmap
[regnum
];
5207 /* Fetch one register. */
5209 fetch_register (const struct usrregs_info
*usrregs
,
5210 struct regcache
*regcache
, int regno
)
5217 if (regno
>= usrregs
->num_regs
)
5219 if ((*the_low_target
.cannot_fetch_register
) (regno
))
5222 regaddr
= register_addr (usrregs
, regno
);
5226 size
= ((register_size (regcache
->tdesc
, regno
)
5227 + sizeof (PTRACE_XFER_TYPE
) - 1)
5228 & -sizeof (PTRACE_XFER_TYPE
));
5229 buf
= (char *) alloca (size
);
5231 pid
= lwpid_of (current_thread
);
5232 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
5235 *(PTRACE_XFER_TYPE
*) (buf
+ i
) =
5236 ptrace (PTRACE_PEEKUSER
, pid
,
5237 /* Coerce to a uintptr_t first to avoid potential gcc warning
5238 of coercing an 8 byte integer to a 4 byte pointer. */
5239 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
, (PTRACE_TYPE_ARG4
) 0);
5240 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
5242 error ("reading register %d: %s", regno
, strerror (errno
));
5245 if (the_low_target
.supply_ptrace_register
)
5246 the_low_target
.supply_ptrace_register (regcache
, regno
, buf
);
5248 supply_register (regcache
, regno
, buf
);
5251 /* Store one register. */
5253 store_register (const struct usrregs_info
*usrregs
,
5254 struct regcache
*regcache
, int regno
)
5261 if (regno
>= usrregs
->num_regs
)
5263 if ((*the_low_target
.cannot_store_register
) (regno
))
5266 regaddr
= register_addr (usrregs
, regno
);
5270 size
= ((register_size (regcache
->tdesc
, regno
)
5271 + sizeof (PTRACE_XFER_TYPE
) - 1)
5272 & -sizeof (PTRACE_XFER_TYPE
));
5273 buf
= (char *) alloca (size
);
5274 memset (buf
, 0, size
);
5276 if (the_low_target
.collect_ptrace_register
)
5277 the_low_target
.collect_ptrace_register (regcache
, regno
, buf
);
5279 collect_register (regcache
, regno
, buf
);
5281 pid
= lwpid_of (current_thread
);
5282 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
5285 ptrace (PTRACE_POKEUSER
, pid
,
5286 /* Coerce to a uintptr_t first to avoid potential gcc warning
5287 about coercing an 8 byte integer to a 4 byte pointer. */
5288 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
,
5289 (PTRACE_TYPE_ARG4
) *(PTRACE_XFER_TYPE
*) (buf
+ i
));
5292 /* At this point, ESRCH should mean the process is
5293 already gone, in which case we simply ignore attempts
5294 to change its registers. See also the related
5295 comment in linux_resume_one_lwp. */
5299 if ((*the_low_target
.cannot_store_register
) (regno
) == 0)
5300 error ("writing register %d: %s", regno
, strerror (errno
));
5302 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
5306 /* Fetch all registers, or just one, from the child process.
5307 If REGNO is -1, do this for all registers, skipping any that are
5308 assumed to have been retrieved by regsets_fetch_inferior_registers,
5309 unless ALL is non-zero.
5310 Otherwise, REGNO specifies which register (so we can save time). */
5312 usr_fetch_inferior_registers (const struct regs_info
*regs_info
,
5313 struct regcache
*regcache
, int regno
, int all
)
5315 struct usrregs_info
*usr
= regs_info
->usrregs
;
5319 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
5320 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
5321 fetch_register (usr
, regcache
, regno
);
5324 fetch_register (usr
, regcache
, regno
);
5327 /* Store our register values back into the inferior.
5328 If REGNO is -1, do this for all registers, skipping any that are
5329 assumed to have been saved by regsets_store_inferior_registers,
5330 unless ALL is non-zero.
5331 Otherwise, REGNO specifies which register (so we can save time). */
5333 usr_store_inferior_registers (const struct regs_info
*regs_info
,
5334 struct regcache
*regcache
, int regno
, int all
)
5336 struct usrregs_info
*usr
= regs_info
->usrregs
;
5340 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
5341 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
5342 store_register (usr
, regcache
, regno
);
5345 store_register (usr
, regcache
, regno
);
5348 #else /* !HAVE_LINUX_USRREGS */
5350 #define usr_fetch_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
5351 #define usr_store_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
5357 linux_fetch_registers (struct regcache
*regcache
, int regno
)
5361 const struct regs_info
*regs_info
= (*the_low_target
.regs_info
) ();
5365 if (the_low_target
.fetch_register
!= NULL
5366 && regs_info
->usrregs
!= NULL
)
5367 for (regno
= 0; regno
< regs_info
->usrregs
->num_regs
; regno
++)
5368 (*the_low_target
.fetch_register
) (regcache
, regno
);
5370 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
, regcache
);
5371 if (regs_info
->usrregs
!= NULL
)
5372 usr_fetch_inferior_registers (regs_info
, regcache
, -1, all
);
5376 if (the_low_target
.fetch_register
!= NULL
5377 && (*the_low_target
.fetch_register
) (regcache
, regno
))
5380 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
5382 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
,
5384 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
5385 usr_fetch_inferior_registers (regs_info
, regcache
, regno
, 1);
5390 linux_store_registers (struct regcache
*regcache
, int regno
)
5394 const struct regs_info
*regs_info
= (*the_low_target
.regs_info
) ();
5398 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
5400 if (regs_info
->usrregs
!= NULL
)
5401 usr_store_inferior_registers (regs_info
, regcache
, regno
, all
);
5405 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
5407 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
5409 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
5410 usr_store_inferior_registers (regs_info
, regcache
, regno
, 1);
5415 /* Copy LEN bytes from inferior's memory starting at MEMADDR
5416 to debugger memory starting at MYADDR. */
5419 linux_read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
, int len
)
5421 int pid
= lwpid_of (current_thread
);
5422 register PTRACE_XFER_TYPE
*buffer
;
5423 register CORE_ADDR addr
;
5430 /* Try using /proc. Don't bother for one word. */
5431 if (len
>= 3 * sizeof (long))
5435 /* We could keep this file open and cache it - possibly one per
5436 thread. That requires some juggling, but is even faster. */
5437 sprintf (filename
, "/proc/%d/mem", pid
);
5438 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
5442 /* If pread64 is available, use it. It's faster if the kernel
5443 supports it (only one syscall), and it's 64-bit safe even on
5444 32-bit platforms (for instance, SPARC debugging a SPARC64
5447 bytes
= pread64 (fd
, myaddr
, len
, memaddr
);
5450 if (lseek (fd
, memaddr
, SEEK_SET
) != -1)
5451 bytes
= read (fd
, myaddr
, len
);
5458 /* Some data was read, we'll try to get the rest with ptrace. */
5468 /* Round starting address down to longword boundary. */
5469 addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
5470 /* Round ending address up; get number of longwords that makes. */
5471 count
= ((((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
5472 / sizeof (PTRACE_XFER_TYPE
));
5473 /* Allocate buffer of that many longwords. */
5474 buffer
= XALLOCAVEC (PTRACE_XFER_TYPE
, count
);
5476 /* Read all the longwords */
5478 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
5480 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5481 about coercing an 8 byte integer to a 4 byte pointer. */
5482 buffer
[i
] = ptrace (PTRACE_PEEKTEXT
, pid
,
5483 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5484 (PTRACE_TYPE_ARG4
) 0);
5490 /* Copy appropriate bytes out of the buffer. */
5493 i
*= sizeof (PTRACE_XFER_TYPE
);
5494 i
-= memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1);
5496 (char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
5503 /* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
5504 memory at MEMADDR. On failure (cannot write to the inferior)
5505 returns the value of errno. Always succeeds if LEN is zero. */
5508 linux_write_memory (CORE_ADDR memaddr
, const unsigned char *myaddr
, int len
)
5511 /* Round starting address down to longword boundary. */
5512 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
5513 /* Round ending address up; get number of longwords that makes. */
5515 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
5516 / sizeof (PTRACE_XFER_TYPE
);
5518 /* Allocate buffer of that many longwords. */
5519 register PTRACE_XFER_TYPE
*buffer
= XALLOCAVEC (PTRACE_XFER_TYPE
, count
);
5521 int pid
= lwpid_of (current_thread
);
5525 /* Zero length write always succeeds. */
5531 /* Dump up to four bytes. */
5532 char str
[4 * 2 + 1];
5534 int dump
= len
< 4 ? len
: 4;
5536 for (i
= 0; i
< dump
; i
++)
5538 sprintf (p
, "%02x", myaddr
[i
]);
5543 debug_printf ("Writing %s to 0x%08lx in process %d\n",
5544 str
, (long) memaddr
, pid
);
5547 /* Fill start and end extra bytes of buffer with existing memory data. */
5550 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5551 about coercing an 8 byte integer to a 4 byte pointer. */
5552 buffer
[0] = ptrace (PTRACE_PEEKTEXT
, pid
,
5553 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5554 (PTRACE_TYPE_ARG4
) 0);
5562 = ptrace (PTRACE_PEEKTEXT
, pid
,
5563 /* Coerce to a uintptr_t first to avoid potential gcc warning
5564 about coercing an 8 byte integer to a 4 byte pointer. */
5565 (PTRACE_TYPE_ARG3
) (uintptr_t) (addr
+ (count
- 1)
5566 * sizeof (PTRACE_XFER_TYPE
)),
5567 (PTRACE_TYPE_ARG4
) 0);
5572 /* Copy data to be written over corresponding part of buffer. */
5574 memcpy ((char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
5577 /* Write the entire buffer. */
5579 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
5582 ptrace (PTRACE_POKETEXT
, pid
,
5583 /* Coerce to a uintptr_t first to avoid potential gcc warning
5584 about coercing an 8 byte integer to a 4 byte pointer. */
5585 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
5586 (PTRACE_TYPE_ARG4
) buffer
[i
]);
5595 linux_look_up_symbols (void)
5597 #ifdef USE_THREAD_DB
5598 struct process_info
*proc
= current_process ();
5600 if (proc
->priv
->thread_db
!= NULL
)
5608 linux_request_interrupt (void)
5610 extern unsigned long signal_pid
;
5612 /* Send a SIGINT to the process group. This acts just like the user
5613 typed a ^C on the controlling terminal. */
5614 kill (-signal_pid
, SIGINT
);
5617 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
5618 to debugger memory starting at MYADDR. */
5621 linux_read_auxv (CORE_ADDR offset
, unsigned char *myaddr
, unsigned int len
)
5623 char filename
[PATH_MAX
];
5625 int pid
= lwpid_of (current_thread
);
5627 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
5629 fd
= open (filename
, O_RDONLY
);
5633 if (offset
!= (CORE_ADDR
) 0
5634 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
5637 n
= read (fd
, myaddr
, len
);
5644 /* These breakpoint and watchpoint related wrapper functions simply
5645 pass on the function call if the target has registered a
5646 corresponding function. */
5649 linux_supports_z_point_type (char z_type
)
5651 return (the_low_target
.supports_z_point_type
!= NULL
5652 && the_low_target
.supports_z_point_type (z_type
));
5656 linux_insert_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
5657 int size
, struct raw_breakpoint
*bp
)
5659 if (type
== raw_bkpt_type_sw
)
5660 return insert_memory_breakpoint (bp
);
5661 else if (the_low_target
.insert_point
!= NULL
)
5662 return the_low_target
.insert_point (type
, addr
, size
, bp
);
5664 /* Unsupported (see target.h). */
5669 linux_remove_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
5670 int size
, struct raw_breakpoint
*bp
)
5672 if (type
== raw_bkpt_type_sw
)
5673 return remove_memory_breakpoint (bp
);
5674 else if (the_low_target
.remove_point
!= NULL
)
5675 return the_low_target
.remove_point (type
, addr
, size
, bp
);
5677 /* Unsupported (see target.h). */
5681 /* Implement the to_stopped_by_sw_breakpoint target_ops
5685 linux_stopped_by_sw_breakpoint (void)
5687 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5689 return (lwp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
);
5692 /* Implement the to_supports_stopped_by_sw_breakpoint target_ops
5696 linux_supports_stopped_by_sw_breakpoint (void)
5698 return USE_SIGTRAP_SIGINFO
;
5701 /* Implement the to_stopped_by_hw_breakpoint target_ops
5705 linux_stopped_by_hw_breakpoint (void)
5707 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5709 return (lwp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
);
5712 /* Implement the to_supports_stopped_by_hw_breakpoint target_ops
5716 linux_supports_stopped_by_hw_breakpoint (void)
5718 return USE_SIGTRAP_SIGINFO
;
5721 /* Implement the supports_hardware_single_step target_ops method. */
5724 linux_supports_hardware_single_step (void)
5726 return can_hardware_single_step ();
5730 linux_supports_software_single_step (void)
5732 return can_software_single_step ();
5736 linux_stopped_by_watchpoint (void)
5738 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5740 return lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
;
5744 linux_stopped_data_address (void)
5746 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5748 return lwp
->stopped_data_address
;
5751 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
5752 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
5753 && defined(PT_TEXT_END_ADDR)
5755 /* This is only used for targets that define PT_TEXT_ADDR,
5756 PT_DATA_ADDR and PT_TEXT_END_ADDR. If those are not defined, supposedly
5757 the target has different ways of acquiring this information, like
5760 /* Under uClinux, programs are loaded at non-zero offsets, which we need
5761 to tell gdb about. */
5764 linux_read_offsets (CORE_ADDR
*text_p
, CORE_ADDR
*data_p
)
5766 unsigned long text
, text_end
, data
;
5767 int pid
= lwpid_of (current_thread
);
5771 text
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_ADDR
,
5772 (PTRACE_TYPE_ARG4
) 0);
5773 text_end
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_END_ADDR
,
5774 (PTRACE_TYPE_ARG4
) 0);
5775 data
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_DATA_ADDR
,
5776 (PTRACE_TYPE_ARG4
) 0);
5780 /* Both text and data offsets produced at compile-time (and so
5781 used by gdb) are relative to the beginning of the program,
5782 with the data segment immediately following the text segment.
5783 However, the actual runtime layout in memory may put the data
5784 somewhere else, so when we send gdb a data base-address, we
5785 use the real data base address and subtract the compile-time
5786 data base-address from it (which is just the length of the
5787 text segment). BSS immediately follows data in both
5790 *data_p
= data
- (text_end
- text
);
5799 linux_qxfer_osdata (const char *annex
,
5800 unsigned char *readbuf
, unsigned const char *writebuf
,
5801 CORE_ADDR offset
, int len
)
5803 return linux_common_xfer_osdata (annex
, readbuf
, offset
, len
);
5806 /* Convert a native/host siginfo object, into/from the siginfo in the
5807 layout of the inferiors' architecture. */
5810 siginfo_fixup (siginfo_t
*siginfo
, void *inf_siginfo
, int direction
)
5814 if (the_low_target
.siginfo_fixup
!= NULL
)
5815 done
= the_low_target
.siginfo_fixup (siginfo
, inf_siginfo
, direction
);
5817 /* If there was no callback, or the callback didn't do anything,
5818 then just do a straight memcpy. */
5822 memcpy (siginfo
, inf_siginfo
, sizeof (siginfo_t
));
5824 memcpy (inf_siginfo
, siginfo
, sizeof (siginfo_t
));
5829 linux_xfer_siginfo (const char *annex
, unsigned char *readbuf
,
5830 unsigned const char *writebuf
, CORE_ADDR offset
, int len
)
5834 char inf_siginfo
[sizeof (siginfo_t
)];
5836 if (current_thread
== NULL
)
5839 pid
= lwpid_of (current_thread
);
5842 debug_printf ("%s siginfo for lwp %d.\n",
5843 readbuf
!= NULL
? "Reading" : "Writing",
5846 if (offset
>= sizeof (siginfo
))
5849 if (ptrace (PTRACE_GETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
5852 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
5853 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
5854 inferior with a 64-bit GDBSERVER should look the same as debugging it
5855 with a 32-bit GDBSERVER, we need to convert it. */
5856 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
5858 if (offset
+ len
> sizeof (siginfo
))
5859 len
= sizeof (siginfo
) - offset
;
5861 if (readbuf
!= NULL
)
5862 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
5865 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
5867 /* Convert back to ptrace layout before flushing it out. */
5868 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
5870 if (ptrace (PTRACE_SETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
5877 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
5878 so we notice when children change state; as the handler for the
5879 sigsuspend in my_waitpid. */
5882 sigchld_handler (int signo
)
5884 int old_errno
= errno
;
5890 /* fprintf is not async-signal-safe, so call write
5892 if (write (2, "sigchld_handler\n",
5893 sizeof ("sigchld_handler\n") - 1) < 0)
5894 break; /* just ignore */
5898 if (target_is_async_p ())
5899 async_file_mark (); /* trigger a linux_wait */
5905 linux_supports_non_stop (void)
5911 linux_async (int enable
)
5913 int previous
= target_is_async_p ();
5916 debug_printf ("linux_async (%d), previous=%d\n",
5919 if (previous
!= enable
)
5922 sigemptyset (&mask
);
5923 sigaddset (&mask
, SIGCHLD
);
5925 sigprocmask (SIG_BLOCK
, &mask
, NULL
);
5929 if (pipe (linux_event_pipe
) == -1)
5931 linux_event_pipe
[0] = -1;
5932 linux_event_pipe
[1] = -1;
5933 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
5935 warning ("creating event pipe failed.");
5939 fcntl (linux_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
5940 fcntl (linux_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
5942 /* Register the event loop handler. */
5943 add_file_handler (linux_event_pipe
[0],
5944 handle_target_event
, NULL
);
5946 /* Always trigger a linux_wait. */
5951 delete_file_handler (linux_event_pipe
[0]);
5953 close (linux_event_pipe
[0]);
5954 close (linux_event_pipe
[1]);
5955 linux_event_pipe
[0] = -1;
5956 linux_event_pipe
[1] = -1;
5959 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
5966 linux_start_non_stop (int nonstop
)
5968 /* Register or unregister from event-loop accordingly. */
5969 linux_async (nonstop
);
5971 if (target_is_async_p () != (nonstop
!= 0))
5978 linux_supports_multi_process (void)
5983 /* Check if fork events are supported. */
5986 linux_supports_fork_events (void)
5988 return linux_supports_tracefork ();
5991 /* Check if vfork events are supported. */
5994 linux_supports_vfork_events (void)
5996 return linux_supports_tracefork ();
5999 /* Check if exec events are supported. */
6002 linux_supports_exec_events (void)
6004 return linux_supports_traceexec ();
6007 /* Callback for 'find_inferior'. Set the (possibly changed) ptrace
6008 options for the specified lwp. */
6011 reset_lwp_ptrace_options_callback (struct inferior_list_entry
*entry
,
6014 struct thread_info
*thread
= (struct thread_info
*) entry
;
6015 struct lwp_info
*lwp
= get_thread_lwp (thread
);
6019 /* Stop the lwp so we can modify its ptrace options. */
6020 lwp
->must_set_ptrace_flags
= 1;
6021 linux_stop_lwp (lwp
);
6025 /* Already stopped; go ahead and set the ptrace options. */
6026 struct process_info
*proc
= find_process_pid (pid_of (thread
));
6027 int options
= linux_low_ptrace_options (proc
->attached
);
6029 linux_enable_event_reporting (lwpid_of (thread
), options
);
6030 lwp
->must_set_ptrace_flags
= 0;
6036 /* Target hook for 'handle_new_gdb_connection'. Causes a reset of the
6037 ptrace flags for all inferiors. This is in case the new GDB connection
6038 doesn't support the same set of events that the previous one did. */
6041 linux_handle_new_gdb_connection (void)
6045 /* Request that all the lwps reset their ptrace options. */
6046 find_inferior (&all_threads
, reset_lwp_ptrace_options_callback
, &pid
);
6050 linux_supports_disable_randomization (void)
6052 #ifdef HAVE_PERSONALITY
6060 linux_supports_agent (void)
6066 linux_supports_range_stepping (void)
6068 if (*the_low_target
.supports_range_stepping
== NULL
)
6071 return (*the_low_target
.supports_range_stepping
) ();
6074 /* Enumerate spufs IDs for process PID. */
6076 spu_enumerate_spu_ids (long pid
, unsigned char *buf
, CORE_ADDR offset
, int len
)
6082 struct dirent
*entry
;
6084 sprintf (path
, "/proc/%ld/fd", pid
);
6085 dir
= opendir (path
);
6090 while ((entry
= readdir (dir
)) != NULL
)
6096 fd
= atoi (entry
->d_name
);
6100 sprintf (path
, "/proc/%ld/fd/%d", pid
, fd
);
6101 if (stat (path
, &st
) != 0)
6103 if (!S_ISDIR (st
.st_mode
))
6106 if (statfs (path
, &stfs
) != 0)
6108 if (stfs
.f_type
!= SPUFS_MAGIC
)
6111 if (pos
>= offset
&& pos
+ 4 <= offset
+ len
)
6113 *(unsigned int *)(buf
+ pos
- offset
) = fd
;
6123 /* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
6124 object type, using the /proc file system. */
6126 linux_qxfer_spu (const char *annex
, unsigned char *readbuf
,
6127 unsigned const char *writebuf
,
6128 CORE_ADDR offset
, int len
)
6130 long pid
= lwpid_of (current_thread
);
6135 if (!writebuf
&& !readbuf
)
6143 return spu_enumerate_spu_ids (pid
, readbuf
, offset
, len
);
6146 sprintf (buf
, "/proc/%ld/fd/%s", pid
, annex
);
6147 fd
= open (buf
, writebuf
? O_WRONLY
: O_RDONLY
);
6152 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
6159 ret
= write (fd
, writebuf
, (size_t) len
);
6161 ret
= read (fd
, readbuf
, (size_t) len
);
6167 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
6168 struct target_loadseg
6170 /* Core address to which the segment is mapped. */
6172 /* VMA recorded in the program header. */
6174 /* Size of this segment in memory. */
6178 # if defined PT_GETDSBT
6179 struct target_loadmap
6181 /* Protocol version number, must be zero. */
6183 /* Pointer to the DSBT table, its size, and the DSBT index. */
6184 unsigned *dsbt_table
;
6185 unsigned dsbt_size
, dsbt_index
;
6186 /* Number of segments in this map. */
6188 /* The actual memory map. */
6189 struct target_loadseg segs
[/*nsegs*/];
6191 # define LINUX_LOADMAP PT_GETDSBT
6192 # define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
6193 # define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
6195 struct target_loadmap
6197 /* Protocol version number, must be zero. */
6199 /* Number of segments in this map. */
6201 /* The actual memory map. */
6202 struct target_loadseg segs
[/*nsegs*/];
6204 # define LINUX_LOADMAP PTRACE_GETFDPIC
6205 # define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
6206 # define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
6210 linux_read_loadmap (const char *annex
, CORE_ADDR offset
,
6211 unsigned char *myaddr
, unsigned int len
)
6213 int pid
= lwpid_of (current_thread
);
6215 struct target_loadmap
*data
= NULL
;
6216 unsigned int actual_length
, copy_length
;
6218 if (strcmp (annex
, "exec") == 0)
6219 addr
= (int) LINUX_LOADMAP_EXEC
;
6220 else if (strcmp (annex
, "interp") == 0)
6221 addr
= (int) LINUX_LOADMAP_INTERP
;
6225 if (ptrace (LINUX_LOADMAP
, pid
, addr
, &data
) != 0)
6231 actual_length
= sizeof (struct target_loadmap
)
6232 + sizeof (struct target_loadseg
) * data
->nsegs
;
6234 if (offset
< 0 || offset
> actual_length
)
6237 copy_length
= actual_length
- offset
< len
? actual_length
- offset
: len
;
6238 memcpy (myaddr
, (char *) data
+ offset
, copy_length
);
6242 # define linux_read_loadmap NULL
6243 #endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
6246 linux_process_qsupported (char **features
, int count
)
6248 if (the_low_target
.process_qsupported
!= NULL
)
6249 the_low_target
.process_qsupported (features
, count
);
6253 linux_supports_tracepoints (void)
6255 if (*the_low_target
.supports_tracepoints
== NULL
)
6258 return (*the_low_target
.supports_tracepoints
) ();
6262 linux_read_pc (struct regcache
*regcache
)
6264 if (the_low_target
.get_pc
== NULL
)
6267 return (*the_low_target
.get_pc
) (regcache
);
6271 linux_write_pc (struct regcache
*regcache
, CORE_ADDR pc
)
6273 gdb_assert (the_low_target
.set_pc
!= NULL
);
6275 (*the_low_target
.set_pc
) (regcache
, pc
);
6279 linux_thread_stopped (struct thread_info
*thread
)
6281 return get_thread_lwp (thread
)->stopped
;
6284 /* This exposes stop-all-threads functionality to other modules. */
6287 linux_pause_all (int freeze
)
6289 stop_all_lwps (freeze
, NULL
);
6292 /* This exposes unstop-all-threads functionality to other gdbserver
6296 linux_unpause_all (int unfreeze
)
6298 unstop_all_lwps (unfreeze
, NULL
);
6302 linux_prepare_to_access_memory (void)
6304 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6307 linux_pause_all (1);
6312 linux_done_accessing_memory (void)
6314 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6317 linux_unpause_all (1);
6321 linux_install_fast_tracepoint_jump_pad (CORE_ADDR tpoint
, CORE_ADDR tpaddr
,
6322 CORE_ADDR collector
,
6325 CORE_ADDR
*jump_entry
,
6326 CORE_ADDR
*trampoline
,
6327 ULONGEST
*trampoline_size
,
6328 unsigned char *jjump_pad_insn
,
6329 ULONGEST
*jjump_pad_insn_size
,
6330 CORE_ADDR
*adjusted_insn_addr
,
6331 CORE_ADDR
*adjusted_insn_addr_end
,
6334 return (*the_low_target
.install_fast_tracepoint_jump_pad
)
6335 (tpoint
, tpaddr
, collector
, lockaddr
, orig_size
,
6336 jump_entry
, trampoline
, trampoline_size
,
6337 jjump_pad_insn
, jjump_pad_insn_size
,
6338 adjusted_insn_addr
, adjusted_insn_addr_end
,
6342 static struct emit_ops
*
6343 linux_emit_ops (void)
6345 if (the_low_target
.emit_ops
!= NULL
)
6346 return (*the_low_target
.emit_ops
) ();
6352 linux_get_min_fast_tracepoint_insn_len (void)
6354 return (*the_low_target
.get_min_fast_tracepoint_insn_len
) ();
6357 /* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
6360 get_phdr_phnum_from_proc_auxv (const int pid
, const int is_elf64
,
6361 CORE_ADDR
*phdr_memaddr
, int *num_phdr
)
6363 char filename
[PATH_MAX
];
6365 const int auxv_size
= is_elf64
6366 ? sizeof (Elf64_auxv_t
) : sizeof (Elf32_auxv_t
);
6367 char buf
[sizeof (Elf64_auxv_t
)]; /* The larger of the two. */
6369 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
6371 fd
= open (filename
, O_RDONLY
);
6377 while (read (fd
, buf
, auxv_size
) == auxv_size
6378 && (*phdr_memaddr
== 0 || *num_phdr
== 0))
6382 Elf64_auxv_t
*const aux
= (Elf64_auxv_t
*) buf
;
6384 switch (aux
->a_type
)
6387 *phdr_memaddr
= aux
->a_un
.a_val
;
6390 *num_phdr
= aux
->a_un
.a_val
;
6396 Elf32_auxv_t
*const aux
= (Elf32_auxv_t
*) buf
;
6398 switch (aux
->a_type
)
6401 *phdr_memaddr
= aux
->a_un
.a_val
;
6404 *num_phdr
= aux
->a_un
.a_val
;
6412 if (*phdr_memaddr
== 0 || *num_phdr
== 0)
6414 warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
6415 "phdr_memaddr = %ld, phdr_num = %d",
6416 (long) *phdr_memaddr
, *num_phdr
);
6423 /* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
6426 get_dynamic (const int pid
, const int is_elf64
)
6428 CORE_ADDR phdr_memaddr
, relocation
;
6430 unsigned char *phdr_buf
;
6431 const int phdr_size
= is_elf64
? sizeof (Elf64_Phdr
) : sizeof (Elf32_Phdr
);
6433 if (get_phdr_phnum_from_proc_auxv (pid
, is_elf64
, &phdr_memaddr
, &num_phdr
))
6436 gdb_assert (num_phdr
< 100); /* Basic sanity check. */
6437 phdr_buf
= (unsigned char *) alloca (num_phdr
* phdr_size
);
6439 if (linux_read_memory (phdr_memaddr
, phdr_buf
, num_phdr
* phdr_size
))
6442 /* Compute relocation: it is expected to be 0 for "regular" executables,
6443 non-zero for PIE ones. */
6445 for (i
= 0; relocation
== -1 && i
< num_phdr
; i
++)
6448 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6450 if (p
->p_type
== PT_PHDR
)
6451 relocation
= phdr_memaddr
- p
->p_vaddr
;
6455 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6457 if (p
->p_type
== PT_PHDR
)
6458 relocation
= phdr_memaddr
- p
->p_vaddr
;
6461 if (relocation
== -1)
6463 /* PT_PHDR is optional, but necessary for PIE in general. Fortunately
6464 any real world executables, including PIE executables, have always
6465 PT_PHDR present. PT_PHDR is not present in some shared libraries or
6466 in fpc (Free Pascal 2.4) binaries but neither of those have a need for
6467 or present DT_DEBUG anyway (fpc binaries are statically linked).
6469 Therefore if there exists DT_DEBUG there is always also PT_PHDR.
6471 GDB could find RELOCATION also from AT_ENTRY - e_entry. */
6476 for (i
= 0; i
< num_phdr
; i
++)
6480 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6482 if (p
->p_type
== PT_DYNAMIC
)
6483 return p
->p_vaddr
+ relocation
;
6487 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
6489 if (p
->p_type
== PT_DYNAMIC
)
6490 return p
->p_vaddr
+ relocation
;
6497 /* Return &_r_debug in the inferior, or -1 if not present. Return value
6498 can be 0 if the inferior does not yet have the library list initialized.
6499 We look for DT_MIPS_RLD_MAP first. MIPS executables use this instead of
6500 DT_DEBUG, although they sometimes contain an unused DT_DEBUG entry too. */
6503 get_r_debug (const int pid
, const int is_elf64
)
6505 CORE_ADDR dynamic_memaddr
;
6506 const int dyn_size
= is_elf64
? sizeof (Elf64_Dyn
) : sizeof (Elf32_Dyn
);
6507 unsigned char buf
[sizeof (Elf64_Dyn
)]; /* The larger of the two. */
6510 dynamic_memaddr
= get_dynamic (pid
, is_elf64
);
6511 if (dynamic_memaddr
== 0)
6514 while (linux_read_memory (dynamic_memaddr
, buf
, dyn_size
) == 0)
6518 Elf64_Dyn
*const dyn
= (Elf64_Dyn
*) buf
;
6519 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
6523 unsigned char buf
[sizeof (Elf64_Xword
)];
6527 #ifdef DT_MIPS_RLD_MAP
6528 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
6530 if (linux_read_memory (dyn
->d_un
.d_val
,
6531 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6536 #endif /* DT_MIPS_RLD_MAP */
6537 #ifdef DT_MIPS_RLD_MAP_REL
6538 if (dyn
->d_tag
== DT_MIPS_RLD_MAP_REL
)
6540 if (linux_read_memory (dyn
->d_un
.d_val
+ dynamic_memaddr
,
6541 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6546 #endif /* DT_MIPS_RLD_MAP_REL */
6548 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
6549 map
= dyn
->d_un
.d_val
;
6551 if (dyn
->d_tag
== DT_NULL
)
6556 Elf32_Dyn
*const dyn
= (Elf32_Dyn
*) buf
;
6557 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
6561 unsigned char buf
[sizeof (Elf32_Word
)];
6565 #ifdef DT_MIPS_RLD_MAP
6566 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
6568 if (linux_read_memory (dyn
->d_un
.d_val
,
6569 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6574 #endif /* DT_MIPS_RLD_MAP */
6575 #ifdef DT_MIPS_RLD_MAP_REL
6576 if (dyn
->d_tag
== DT_MIPS_RLD_MAP_REL
)
6578 if (linux_read_memory (dyn
->d_un
.d_val
+ dynamic_memaddr
,
6579 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
6584 #endif /* DT_MIPS_RLD_MAP_REL */
6586 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
6587 map
= dyn
->d_un
.d_val
;
6589 if (dyn
->d_tag
== DT_NULL
)
6593 dynamic_memaddr
+= dyn_size
;
6599 /* Read one pointer from MEMADDR in the inferior. */
6602 read_one_ptr (CORE_ADDR memaddr
, CORE_ADDR
*ptr
, int ptr_size
)
6606 /* Go through a union so this works on either big or little endian
6607 hosts, when the inferior's pointer size is smaller than the size
6608 of CORE_ADDR. It is assumed the inferior's endianness is the
6609 same of the superior's. */
6612 CORE_ADDR core_addr
;
6617 ret
= linux_read_memory (memaddr
, &addr
.uc
, ptr_size
);
6620 if (ptr_size
== sizeof (CORE_ADDR
))
6621 *ptr
= addr
.core_addr
;
6622 else if (ptr_size
== sizeof (unsigned int))
6625 gdb_assert_not_reached ("unhandled pointer size");
6630 struct link_map_offsets
6632 /* Offset and size of r_debug.r_version. */
6633 int r_version_offset
;
6635 /* Offset and size of r_debug.r_map. */
6638 /* Offset to l_addr field in struct link_map. */
6641 /* Offset to l_name field in struct link_map. */
6644 /* Offset to l_ld field in struct link_map. */
6647 /* Offset to l_next field in struct link_map. */
6650 /* Offset to l_prev field in struct link_map. */
6654 /* Construct qXfer:libraries-svr4:read reply. */
6657 linux_qxfer_libraries_svr4 (const char *annex
, unsigned char *readbuf
,
6658 unsigned const char *writebuf
,
6659 CORE_ADDR offset
, int len
)
6662 unsigned document_len
;
6663 struct process_info_private
*const priv
= current_process ()->priv
;
6664 char filename
[PATH_MAX
];
6667 static const struct link_map_offsets lmo_32bit_offsets
=
6669 0, /* r_version offset. */
6670 4, /* r_debug.r_map offset. */
6671 0, /* l_addr offset in link_map. */
6672 4, /* l_name offset in link_map. */
6673 8, /* l_ld offset in link_map. */
6674 12, /* l_next offset in link_map. */
6675 16 /* l_prev offset in link_map. */
6678 static const struct link_map_offsets lmo_64bit_offsets
=
6680 0, /* r_version offset. */
6681 8, /* r_debug.r_map offset. */
6682 0, /* l_addr offset in link_map. */
6683 8, /* l_name offset in link_map. */
6684 16, /* l_ld offset in link_map. */
6685 24, /* l_next offset in link_map. */
6686 32 /* l_prev offset in link_map. */
6688 const struct link_map_offsets
*lmo
;
6689 unsigned int machine
;
6691 CORE_ADDR lm_addr
= 0, lm_prev
= 0;
6692 int allocated
= 1024;
6694 CORE_ADDR l_name
, l_addr
, l_ld
, l_next
, l_prev
;
6695 int header_done
= 0;
6697 if (writebuf
!= NULL
)
6699 if (readbuf
== NULL
)
6702 pid
= lwpid_of (current_thread
);
6703 xsnprintf (filename
, sizeof filename
, "/proc/%d/exe", pid
);
6704 is_elf64
= elf_64_file_p (filename
, &machine
);
6705 lmo
= is_elf64
? &lmo_64bit_offsets
: &lmo_32bit_offsets
;
6706 ptr_size
= is_elf64
? 8 : 4;
6708 while (annex
[0] != '\0')
6714 sep
= strchr (annex
, '=');
6719 if (len
== 5 && startswith (annex
, "start"))
6721 else if (len
== 4 && startswith (annex
, "prev"))
6725 annex
= strchr (sep
, ';');
6732 annex
= decode_address_to_semicolon (addrp
, sep
+ 1);
6739 if (priv
->r_debug
== 0)
6740 priv
->r_debug
= get_r_debug (pid
, is_elf64
);
6742 /* We failed to find DT_DEBUG. Such situation will not change
6743 for this inferior - do not retry it. Report it to GDB as
6744 E01, see for the reasons at the GDB solib-svr4.c side. */
6745 if (priv
->r_debug
== (CORE_ADDR
) -1)
6748 if (priv
->r_debug
!= 0)
6750 if (linux_read_memory (priv
->r_debug
+ lmo
->r_version_offset
,
6751 (unsigned char *) &r_version
,
6752 sizeof (r_version
)) != 0
6755 warning ("unexpected r_debug version %d", r_version
);
6757 else if (read_one_ptr (priv
->r_debug
+ lmo
->r_map_offset
,
6758 &lm_addr
, ptr_size
) != 0)
6760 warning ("unable to read r_map from 0x%lx",
6761 (long) priv
->r_debug
+ lmo
->r_map_offset
);
6766 document
= (char *) xmalloc (allocated
);
6767 strcpy (document
, "<library-list-svr4 version=\"1.0\"");
6768 p
= document
+ strlen (document
);
6771 && read_one_ptr (lm_addr
+ lmo
->l_name_offset
,
6772 &l_name
, ptr_size
) == 0
6773 && read_one_ptr (lm_addr
+ lmo
->l_addr_offset
,
6774 &l_addr
, ptr_size
) == 0
6775 && read_one_ptr (lm_addr
+ lmo
->l_ld_offset
,
6776 &l_ld
, ptr_size
) == 0
6777 && read_one_ptr (lm_addr
+ lmo
->l_prev_offset
,
6778 &l_prev
, ptr_size
) == 0
6779 && read_one_ptr (lm_addr
+ lmo
->l_next_offset
,
6780 &l_next
, ptr_size
) == 0)
6782 unsigned char libname
[PATH_MAX
];
6784 if (lm_prev
!= l_prev
)
6786 warning ("Corrupted shared library list: 0x%lx != 0x%lx",
6787 (long) lm_prev
, (long) l_prev
);
6791 /* Ignore the first entry even if it has valid name as the first entry
6792 corresponds to the main executable. The first entry should not be
6793 skipped if the dynamic loader was loaded late by a static executable
6794 (see solib-svr4.c parameter ignore_first). But in such case the main
6795 executable does not have PT_DYNAMIC present and this function already
6796 exited above due to failed get_r_debug. */
6799 sprintf (p
, " main-lm=\"0x%lx\"", (unsigned long) lm_addr
);
6804 /* Not checking for error because reading may stop before
6805 we've got PATH_MAX worth of characters. */
6807 linux_read_memory (l_name
, libname
, sizeof (libname
) - 1);
6808 libname
[sizeof (libname
) - 1] = '\0';
6809 if (libname
[0] != '\0')
6811 /* 6x the size for xml_escape_text below. */
6812 size_t len
= 6 * strlen ((char *) libname
);
6817 /* Terminate `<library-list-svr4'. */
6822 while (allocated
< p
- document
+ len
+ 200)
6824 /* Expand to guarantee sufficient storage. */
6825 uintptr_t document_len
= p
- document
;
6827 document
= (char *) xrealloc (document
, 2 * allocated
);
6829 p
= document
+ document_len
;
6832 name
= xml_escape_text ((char *) libname
);
6833 p
+= sprintf (p
, "<library name=\"%s\" lm=\"0x%lx\" "
6834 "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
6835 name
, (unsigned long) lm_addr
,
6836 (unsigned long) l_addr
, (unsigned long) l_ld
);
6847 /* Empty list; terminate `<library-list-svr4'. */
6851 strcpy (p
, "</library-list-svr4>");
6853 document_len
= strlen (document
);
6854 if (offset
< document_len
)
6855 document_len
-= offset
;
6858 if (len
> document_len
)
6861 memcpy (readbuf
, document
+ offset
, len
);
6867 #ifdef HAVE_LINUX_BTRACE
6869 /* See to_disable_btrace target method. */
6872 linux_low_disable_btrace (struct btrace_target_info
*tinfo
)
6874 enum btrace_error err
;
6876 err
= linux_disable_btrace (tinfo
);
6877 return (err
== BTRACE_ERR_NONE
? 0 : -1);
6880 /* Encode an Intel(R) Processor Trace configuration. */
6883 linux_low_encode_pt_config (struct buffer
*buffer
,
6884 const struct btrace_data_pt_config
*config
)
6886 buffer_grow_str (buffer
, "<pt-config>\n");
6888 switch (config
->cpu
.vendor
)
6891 buffer_xml_printf (buffer
, "<cpu vendor=\"GenuineIntel\" family=\"%u\" "
6892 "model=\"%u\" stepping=\"%u\"/>\n",
6893 config
->cpu
.family
, config
->cpu
.model
,
6894 config
->cpu
.stepping
);
6901 buffer_grow_str (buffer
, "</pt-config>\n");
6904 /* Encode a raw buffer. */
6907 linux_low_encode_raw (struct buffer
*buffer
, const gdb_byte
*data
,
6913 /* We use hex encoding - see common/rsp-low.h. */
6914 buffer_grow_str (buffer
, "<raw>\n");
6920 elem
[0] = tohex ((*data
>> 4) & 0xf);
6921 elem
[1] = tohex (*data
++ & 0xf);
6923 buffer_grow (buffer
, elem
, 2);
6926 buffer_grow_str (buffer
, "</raw>\n");
6929 /* See to_read_btrace target method. */
6932 linux_low_read_btrace (struct btrace_target_info
*tinfo
, struct buffer
*buffer
,
6933 enum btrace_read_type type
)
6935 struct btrace_data btrace
;
6936 struct btrace_block
*block
;
6937 enum btrace_error err
;
6940 btrace_data_init (&btrace
);
6942 err
= linux_read_btrace (&btrace
, tinfo
, type
);
6943 if (err
!= BTRACE_ERR_NONE
)
6945 if (err
== BTRACE_ERR_OVERFLOW
)
6946 buffer_grow_str0 (buffer
, "E.Overflow.");
6948 buffer_grow_str0 (buffer
, "E.Generic Error.");
6953 switch (btrace
.format
)
6955 case BTRACE_FORMAT_NONE
:
6956 buffer_grow_str0 (buffer
, "E.No Trace.");
6959 case BTRACE_FORMAT_BTS
:
6960 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
6961 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
6964 VEC_iterate (btrace_block_s
, btrace
.variant
.bts
.blocks
, i
, block
);
6966 buffer_xml_printf (buffer
, "<block begin=\"0x%s\" end=\"0x%s\"/>\n",
6967 paddress (block
->begin
), paddress (block
->end
));
6969 buffer_grow_str0 (buffer
, "</btrace>\n");
6972 case BTRACE_FORMAT_PT
:
6973 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
6974 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
6975 buffer_grow_str (buffer
, "<pt>\n");
6977 linux_low_encode_pt_config (buffer
, &btrace
.variant
.pt
.config
);
6979 linux_low_encode_raw (buffer
, btrace
.variant
.pt
.data
,
6980 btrace
.variant
.pt
.size
);
6982 buffer_grow_str (buffer
, "</pt>\n");
6983 buffer_grow_str0 (buffer
, "</btrace>\n");
6987 buffer_grow_str0 (buffer
, "E.Unsupported Trace Format.");
6991 btrace_data_fini (&btrace
);
6995 btrace_data_fini (&btrace
);
6999 /* See to_btrace_conf target method. */
7002 linux_low_btrace_conf (const struct btrace_target_info
*tinfo
,
7003 struct buffer
*buffer
)
7005 const struct btrace_config
*conf
;
7007 buffer_grow_str (buffer
, "<!DOCTYPE btrace-conf SYSTEM \"btrace-conf.dtd\">\n");
7008 buffer_grow_str (buffer
, "<btrace-conf version=\"1.0\">\n");
7010 conf
= linux_btrace_conf (tinfo
);
7013 switch (conf
->format
)
7015 case BTRACE_FORMAT_NONE
:
7018 case BTRACE_FORMAT_BTS
:
7019 buffer_xml_printf (buffer
, "<bts");
7020 buffer_xml_printf (buffer
, " size=\"0x%x\"", conf
->bts
.size
);
7021 buffer_xml_printf (buffer
, " />\n");
7024 case BTRACE_FORMAT_PT
:
7025 buffer_xml_printf (buffer
, "<pt");
7026 buffer_xml_printf (buffer
, " size=\"0x%x\"", conf
->pt
.size
);
7027 buffer_xml_printf (buffer
, "/>\n");
7032 buffer_grow_str0 (buffer
, "</btrace-conf>\n");
7035 #endif /* HAVE_LINUX_BTRACE */
7037 /* See nat/linux-nat.h. */
7040 current_lwp_ptid (void)
7042 return ptid_of (current_thread
);
7045 /* Implementation of the target_ops method "breakpoint_kind_from_pc". */
7048 linux_breakpoint_kind_from_pc (CORE_ADDR
*pcptr
)
7050 if (the_low_target
.breakpoint_kind_from_pc
!= NULL
)
7051 return (*the_low_target
.breakpoint_kind_from_pc
) (pcptr
);
7053 return default_breakpoint_kind_from_pc (pcptr
);
7056 /* Implementation of the target_ops method "sw_breakpoint_from_kind". */
7058 static const gdb_byte
*
7059 linux_sw_breakpoint_from_kind (int kind
, int *size
)
7061 gdb_assert (the_low_target
.sw_breakpoint_from_kind
!= NULL
);
7063 return (*the_low_target
.sw_breakpoint_from_kind
) (kind
, size
);
7066 /* Implementation of the target_ops method
7067 "breakpoint_kind_from_current_state". */
7070 linux_breakpoint_kind_from_current_state (CORE_ADDR
*pcptr
)
7072 if (the_low_target
.breakpoint_kind_from_current_state
!= NULL
)
7073 return (*the_low_target
.breakpoint_kind_from_current_state
) (pcptr
);
7075 return linux_breakpoint_kind_from_pc (pcptr
);
7078 static struct target_ops linux_target_ops
= {
7079 linux_create_inferior
,
7089 linux_fetch_registers
,
7090 linux_store_registers
,
7091 linux_prepare_to_access_memory
,
7092 linux_done_accessing_memory
,
7095 linux_look_up_symbols
,
7096 linux_request_interrupt
,
7098 linux_supports_z_point_type
,
7101 linux_stopped_by_sw_breakpoint
,
7102 linux_supports_stopped_by_sw_breakpoint
,
7103 linux_stopped_by_hw_breakpoint
,
7104 linux_supports_stopped_by_hw_breakpoint
,
7105 linux_supports_hardware_single_step
,
7106 linux_stopped_by_watchpoint
,
7107 linux_stopped_data_address
,
7108 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
7109 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
7110 && defined(PT_TEXT_END_ADDR)
7115 #ifdef USE_THREAD_DB
7116 thread_db_get_tls_address
,
7121 hostio_last_error_from_errno
,
7124 linux_supports_non_stop
,
7126 linux_start_non_stop
,
7127 linux_supports_multi_process
,
7128 linux_supports_fork_events
,
7129 linux_supports_vfork_events
,
7130 linux_supports_exec_events
,
7131 linux_handle_new_gdb_connection
,
7132 #ifdef USE_THREAD_DB
7133 thread_db_handle_monitor_command
,
7137 linux_common_core_of_thread
,
7139 linux_process_qsupported
,
7140 linux_supports_tracepoints
,
7143 linux_thread_stopped
,
7147 linux_stabilize_threads
,
7148 linux_install_fast_tracepoint_jump_pad
,
7150 linux_supports_disable_randomization
,
7151 linux_get_min_fast_tracepoint_insn_len
,
7152 linux_qxfer_libraries_svr4
,
7153 linux_supports_agent
,
7154 #ifdef HAVE_LINUX_BTRACE
7155 linux_supports_btrace
,
7156 linux_enable_btrace
,
7157 linux_low_disable_btrace
,
7158 linux_low_read_btrace
,
7159 linux_low_btrace_conf
,
7167 linux_supports_range_stepping
,
7168 linux_proc_pid_to_exec_file
,
7169 linux_mntns_open_cloexec
,
7171 linux_mntns_readlink
,
7172 linux_breakpoint_kind_from_pc
,
7173 linux_sw_breakpoint_from_kind
,
7174 linux_proc_tid_get_name
,
7175 linux_breakpoint_kind_from_current_state
,
7176 linux_supports_software_single_step
7180 linux_init_signals ()
7182 /* FIXME drow/2002-06-09: As above, we should check with LinuxThreads
7183 to find what the cancel signal actually is. */
7184 #ifndef __ANDROID__ /* Bionic doesn't use SIGRTMIN the way glibc does. */
7185 signal (__SIGRTMIN
+1, SIG_IGN
);
7189 #ifdef HAVE_LINUX_REGSETS
7191 initialize_regsets_info (struct regsets_info
*info
)
7193 for (info
->num_regsets
= 0;
7194 info
->regsets
[info
->num_regsets
].size
>= 0;
7195 info
->num_regsets
++)
7201 initialize_low (void)
7203 struct sigaction sigchld_action
;
7205 memset (&sigchld_action
, 0, sizeof (sigchld_action
));
7206 set_target_ops (&linux_target_ops
);
7208 linux_init_signals ();
7209 linux_ptrace_init_warnings ();
7211 sigchld_action
.sa_handler
= sigchld_handler
;
7212 sigemptyset (&sigchld_action
.sa_mask
);
7213 sigchld_action
.sa_flags
= SA_RESTART
;
7214 sigaction (SIGCHLD
, &sigchld_action
, NULL
);
7216 initialize_low_arch ();
7218 linux_check_ptrace_features ();