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"
24 #include "nat/linux-nat.h"
25 #include "nat/linux-waitpid.h"
27 #include <sys/ptrace.h>
28 #include "nat/linux-ptrace.h"
29 #include "nat/linux-procfs.h"
30 #include "nat/linux-personality.h"
32 #include <sys/ioctl.h>
35 #include <sys/syscall.h>
39 #include <sys/types.h>
44 #include "filestuff.h"
45 #include "tracepoint.h"
48 /* Don't include <linux/elf.h> here. If it got included by gdb_proc_service.h
49 then ELFMAG0 will have been defined. If it didn't get included by
50 gdb_proc_service.h then including it will likely introduce a duplicate
51 definition of elf_fpregset_t. */
56 #define SPUFS_MAGIC 0x23c9b64e
59 #ifdef HAVE_PERSONALITY
60 # include <sys/personality.h>
61 # if !HAVE_DECL_ADDR_NO_RANDOMIZE
62 # define ADDR_NO_RANDOMIZE 0x0040000
71 #define W_STOPCODE(sig) ((sig) << 8 | 0x7f)
74 /* This is the kernel's hard limit. Not to be confused with
80 /* Some targets did not define these ptrace constants from the start,
81 so gdbserver defines them locally here. In the future, these may
82 be removed after they are added to asm/ptrace.h. */
83 #if !(defined(PT_TEXT_ADDR) \
84 || defined(PT_DATA_ADDR) \
85 || defined(PT_TEXT_END_ADDR))
86 #if defined(__mcoldfire__)
87 /* These are still undefined in 3.10 kernels. */
88 #define PT_TEXT_ADDR 49*4
89 #define PT_DATA_ADDR 50*4
90 #define PT_TEXT_END_ADDR 51*4
91 /* BFIN already defines these since at least 2.6.32 kernels. */
93 #define PT_TEXT_ADDR 220
94 #define PT_TEXT_END_ADDR 224
95 #define PT_DATA_ADDR 228
96 /* These are still undefined in 3.10 kernels. */
97 #elif defined(__TMS320C6X__)
98 #define PT_TEXT_ADDR (0x10000*4)
99 #define PT_DATA_ADDR (0x10004*4)
100 #define PT_TEXT_END_ADDR (0x10008*4)
104 #ifdef HAVE_LINUX_BTRACE
105 # include "nat/linux-btrace.h"
106 # include "btrace-common.h"
109 #ifndef HAVE_ELF32_AUXV_T
110 /* Copied from glibc's elf.h. */
113 uint32_t a_type
; /* Entry type */
116 uint32_t a_val
; /* Integer value */
117 /* We use to have pointer elements added here. We cannot do that,
118 though, since it does not work when using 32-bit definitions
119 on 64-bit platforms and vice versa. */
124 #ifndef HAVE_ELF64_AUXV_T
125 /* Copied from glibc's elf.h. */
128 uint64_t a_type
; /* Entry type */
131 uint64_t a_val
; /* Integer value */
132 /* We use to have pointer elements added here. We cannot do that,
133 though, since it does not work when using 32-bit definitions
134 on 64-bit platforms and vice versa. */
139 /* A list of all unknown processes which receive stop signals. Some
140 other process will presumably claim each of these as forked
141 children momentarily. */
143 struct simple_pid_list
145 /* The process ID. */
148 /* The status as reported by waitpid. */
152 struct simple_pid_list
*next
;
154 struct simple_pid_list
*stopped_pids
;
156 /* Trivial list manipulation functions to keep track of a list of new
157 stopped processes. */
160 add_to_pid_list (struct simple_pid_list
**listp
, int pid
, int status
)
162 struct simple_pid_list
*new_pid
= xmalloc (sizeof (struct simple_pid_list
));
165 new_pid
->status
= status
;
166 new_pid
->next
= *listp
;
171 pull_pid_from_list (struct simple_pid_list
**listp
, int pid
, int *statusp
)
173 struct simple_pid_list
**p
;
175 for (p
= listp
; *p
!= NULL
; p
= &(*p
)->next
)
176 if ((*p
)->pid
== pid
)
178 struct simple_pid_list
*next
= (*p
)->next
;
180 *statusp
= (*p
)->status
;
188 enum stopping_threads_kind
190 /* Not stopping threads presently. */
191 NOT_STOPPING_THREADS
,
193 /* Stopping threads. */
196 /* Stopping and suspending threads. */
197 STOPPING_AND_SUSPENDING_THREADS
200 /* This is set while stop_all_lwps is in effect. */
201 enum stopping_threads_kind stopping_threads
= NOT_STOPPING_THREADS
;
203 /* FIXME make into a target method? */
204 int using_threads
= 1;
206 /* True if we're presently stabilizing threads (moving them out of
208 static int stabilizing_threads
;
210 static void linux_resume_one_lwp (struct lwp_info
*lwp
,
211 int step
, int signal
, siginfo_t
*info
);
212 static void linux_resume (struct thread_resume
*resume_info
, size_t n
);
213 static void stop_all_lwps (int suspend
, struct lwp_info
*except
);
214 static void unstop_all_lwps (int unsuspend
, struct lwp_info
*except
);
215 static int linux_wait_for_event_filtered (ptid_t wait_ptid
, ptid_t filter_ptid
,
216 int *wstat
, int options
);
217 static int linux_wait_for_event (ptid_t ptid
, int *wstat
, int options
);
218 static struct lwp_info
*add_lwp (ptid_t ptid
);
219 static int linux_stopped_by_watchpoint (void);
220 static void mark_lwp_dead (struct lwp_info
*lwp
, int wstat
);
221 static void proceed_all_lwps (void);
222 static int finish_step_over (struct lwp_info
*lwp
);
223 static int kill_lwp (unsigned long lwpid
, int signo
);
225 /* When the event-loop is doing a step-over, this points at the thread
227 ptid_t step_over_bkpt
;
229 /* True if the low target can hardware single-step. Such targets
230 don't need a BREAKPOINT_REINSERT_ADDR callback. */
233 can_hardware_single_step (void)
235 return (the_low_target
.breakpoint_reinsert_addr
== NULL
);
238 /* True if the low target supports memory breakpoints. If so, we'll
239 have a GET_PC implementation. */
242 supports_breakpoints (void)
244 return (the_low_target
.get_pc
!= NULL
);
247 /* Returns true if this target can support fast tracepoints. This
248 does not mean that the in-process agent has been loaded in the
252 supports_fast_tracepoints (void)
254 return the_low_target
.install_fast_tracepoint_jump_pad
!= NULL
;
257 /* True if LWP is stopped in its stepping range. */
260 lwp_in_step_range (struct lwp_info
*lwp
)
262 CORE_ADDR pc
= lwp
->stop_pc
;
264 return (pc
>= lwp
->step_range_start
&& pc
< lwp
->step_range_end
);
267 struct pending_signals
271 struct pending_signals
*prev
;
274 /* The read/write ends of the pipe registered as waitable file in the
276 static int linux_event_pipe
[2] = { -1, -1 };
278 /* True if we're currently in async mode. */
279 #define target_is_async_p() (linux_event_pipe[0] != -1)
281 static void send_sigstop (struct lwp_info
*lwp
);
282 static void wait_for_sigstop (void);
284 /* Return non-zero if HEADER is a 64-bit ELF file. */
287 elf_64_header_p (const Elf64_Ehdr
*header
, unsigned int *machine
)
289 if (header
->e_ident
[EI_MAG0
] == ELFMAG0
290 && header
->e_ident
[EI_MAG1
] == ELFMAG1
291 && header
->e_ident
[EI_MAG2
] == ELFMAG2
292 && header
->e_ident
[EI_MAG3
] == ELFMAG3
)
294 *machine
= header
->e_machine
;
295 return header
->e_ident
[EI_CLASS
] == ELFCLASS64
;
302 /* Return non-zero if FILE is a 64-bit ELF file,
303 zero if the file is not a 64-bit ELF file,
304 and -1 if the file is not accessible or doesn't exist. */
307 elf_64_file_p (const char *file
, unsigned int *machine
)
312 fd
= open (file
, O_RDONLY
);
316 if (read (fd
, &header
, sizeof (header
)) != sizeof (header
))
323 return elf_64_header_p (&header
, machine
);
326 /* Accepts an integer PID; Returns true if the executable PID is
327 running is a 64-bit ELF file.. */
330 linux_pid_exe_is_elf_64_file (int pid
, unsigned int *machine
)
334 sprintf (file
, "/proc/%d/exe", pid
);
335 return elf_64_file_p (file
, machine
);
339 delete_lwp (struct lwp_info
*lwp
)
341 struct thread_info
*thr
= get_lwp_thread (lwp
);
344 debug_printf ("deleting %ld\n", lwpid_of (thr
));
347 free (lwp
->arch_private
);
351 /* Add a process to the common process list, and set its private
354 static struct process_info
*
355 linux_add_process (int pid
, int attached
)
357 struct process_info
*proc
;
359 proc
= add_process (pid
, attached
);
360 proc
->priv
= xcalloc (1, sizeof (*proc
->priv
));
362 /* Set the arch when the first LWP stops. */
363 proc
->priv
->new_inferior
= 1;
365 if (the_low_target
.new_process
!= NULL
)
366 proc
->priv
->arch_private
= the_low_target
.new_process ();
371 static CORE_ADDR
get_pc (struct lwp_info
*lwp
);
373 /* Handle a GNU/Linux extended wait response. If we see a clone
374 event, we need to add the new LWP to our list (and not report the
375 trap to higher layers). */
378 handle_extended_wait (struct lwp_info
*event_child
, int wstat
)
380 int event
= linux_ptrace_get_extended_event (wstat
);
381 struct thread_info
*event_thr
= get_lwp_thread (event_child
);
382 struct lwp_info
*new_lwp
;
384 if (event
== PTRACE_EVENT_CLONE
)
387 unsigned long new_pid
;
390 ptrace (PTRACE_GETEVENTMSG
, lwpid_of (event_thr
), (PTRACE_TYPE_ARG3
) 0,
393 /* If we haven't already seen the new PID stop, wait for it now. */
394 if (!pull_pid_from_list (&stopped_pids
, new_pid
, &status
))
396 /* The new child has a pending SIGSTOP. We can't affect it until it
397 hits the SIGSTOP, but we're already attached. */
399 ret
= my_waitpid (new_pid
, &status
, __WALL
);
402 perror_with_name ("waiting for new child");
403 else if (ret
!= new_pid
)
404 warning ("wait returned unexpected PID %d", ret
);
405 else if (!WIFSTOPPED (status
))
406 warning ("wait returned unexpected status 0x%x", status
);
410 debug_printf ("HEW: Got clone event "
411 "from LWP %ld, new child is LWP %ld\n",
412 lwpid_of (event_thr
), new_pid
);
414 ptid
= ptid_build (pid_of (event_thr
), new_pid
, 0);
415 new_lwp
= add_lwp (ptid
);
417 /* Either we're going to immediately resume the new thread
418 or leave it stopped. linux_resume_one_lwp is a nop if it
419 thinks the thread is currently running, so set this first
420 before calling linux_resume_one_lwp. */
421 new_lwp
->stopped
= 1;
423 /* If we're suspending all threads, leave this one suspended
425 if (stopping_threads
== STOPPING_AND_SUSPENDING_THREADS
)
426 new_lwp
->suspended
= 1;
428 /* Normally we will get the pending SIGSTOP. But in some cases
429 we might get another signal delivered to the group first.
430 If we do get another signal, be sure not to lose it. */
431 if (WSTOPSIG (status
) != SIGSTOP
)
433 new_lwp
->stop_expected
= 1;
434 new_lwp
->status_pending_p
= 1;
435 new_lwp
->status_pending
= status
;
440 /* Return the PC as read from the regcache of LWP, without any
444 get_pc (struct lwp_info
*lwp
)
446 struct thread_info
*saved_thread
;
447 struct regcache
*regcache
;
450 if (the_low_target
.get_pc
== NULL
)
453 saved_thread
= current_thread
;
454 current_thread
= get_lwp_thread (lwp
);
456 regcache
= get_thread_regcache (current_thread
, 1);
457 pc
= (*the_low_target
.get_pc
) (regcache
);
460 debug_printf ("pc is 0x%lx\n", (long) pc
);
462 current_thread
= saved_thread
;
466 /* This function should only be called if LWP got a SIGTRAP.
467 The SIGTRAP could mean several things.
469 On i386, where decr_pc_after_break is non-zero:
471 If we were single-stepping this process using PTRACE_SINGLESTEP, we
472 will get only the one SIGTRAP. The value of $eip will be the next
473 instruction. If the instruction we stepped over was a breakpoint,
474 we need to decrement the PC.
476 If we continue the process using PTRACE_CONT, we will get a
477 SIGTRAP when we hit a breakpoint. The value of $eip will be
478 the instruction after the breakpoint (i.e. needs to be
479 decremented). If we report the SIGTRAP to GDB, we must also
480 report the undecremented PC. If the breakpoint is removed, we
481 must resume at the decremented PC.
483 On a non-decr_pc_after_break machine with hardware or kernel
486 If we either single-step a breakpoint instruction, or continue and
487 hit a breakpoint instruction, our PC will point at the breakpoint
491 check_stopped_by_breakpoint (struct lwp_info
*lwp
)
494 CORE_ADDR sw_breakpoint_pc
;
495 struct thread_info
*saved_thread
;
496 #if USE_SIGTRAP_SIGINFO
500 if (the_low_target
.get_pc
== NULL
)
504 sw_breakpoint_pc
= pc
- the_low_target
.decr_pc_after_break
;
506 /* breakpoint_at reads from the current thread. */
507 saved_thread
= current_thread
;
508 current_thread
= get_lwp_thread (lwp
);
510 #if USE_SIGTRAP_SIGINFO
511 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
512 (PTRACE_TYPE_ARG3
) 0, &siginfo
) == 0)
514 if (siginfo
.si_signo
== SIGTRAP
)
516 if (siginfo
.si_code
== GDB_ARCH_TRAP_BRKPT
)
520 struct thread_info
*thr
= get_lwp_thread (lwp
);
522 debug_printf ("CSBB: Push back software breakpoint for %s\n",
523 target_pid_to_str (ptid_of (thr
)));
526 /* Back up the PC if necessary. */
527 if (pc
!= sw_breakpoint_pc
)
529 struct regcache
*regcache
530 = get_thread_regcache (current_thread
, 1);
531 (*the_low_target
.set_pc
) (regcache
, sw_breakpoint_pc
);
534 lwp
->stop_pc
= sw_breakpoint_pc
;
535 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
536 current_thread
= saved_thread
;
539 else if (siginfo
.si_code
== TRAP_HWBKPT
)
543 struct thread_info
*thr
= get_lwp_thread (lwp
);
545 debug_printf ("CSBB: Push back hardware "
546 "breakpoint/watchpoint for %s\n",
547 target_pid_to_str (ptid_of (thr
)));
551 lwp
->stop_reason
= TARGET_STOPPED_BY_HW_BREAKPOINT
;
552 current_thread
= saved_thread
;
558 /* We may have just stepped a breakpoint instruction. E.g., in
559 non-stop mode, GDB first tells the thread A to step a range, and
560 then the user inserts a breakpoint inside the range. In that
561 case we need to report the breakpoint PC. */
562 if ((!lwp
->stepping
|| lwp
->stop_pc
== sw_breakpoint_pc
)
563 && (*the_low_target
.breakpoint_at
) (sw_breakpoint_pc
))
567 struct thread_info
*thr
= get_lwp_thread (lwp
);
569 debug_printf ("CSBB: %s stopped by software breakpoint\n",
570 target_pid_to_str (ptid_of (thr
)));
573 /* Back up the PC if necessary. */
574 if (pc
!= sw_breakpoint_pc
)
576 struct regcache
*regcache
577 = get_thread_regcache (current_thread
, 1);
578 (*the_low_target
.set_pc
) (regcache
, sw_breakpoint_pc
);
581 lwp
->stop_pc
= sw_breakpoint_pc
;
582 lwp
->stop_reason
= TARGET_STOPPED_BY_SW_BREAKPOINT
;
583 current_thread
= saved_thread
;
587 if (hardware_breakpoint_inserted_here (pc
))
591 struct thread_info
*thr
= get_lwp_thread (lwp
);
593 debug_printf ("CSBB: %s stopped by hardware breakpoint\n",
594 target_pid_to_str (ptid_of (thr
)));
598 lwp
->stop_reason
= TARGET_STOPPED_BY_HW_BREAKPOINT
;
599 current_thread
= saved_thread
;
604 current_thread
= saved_thread
;
608 static struct lwp_info
*
609 add_lwp (ptid_t ptid
)
611 struct lwp_info
*lwp
;
613 lwp
= (struct lwp_info
*) xmalloc (sizeof (*lwp
));
614 memset (lwp
, 0, sizeof (*lwp
));
616 if (the_low_target
.new_thread
!= NULL
)
617 lwp
->arch_private
= the_low_target
.new_thread ();
619 lwp
->thread
= add_thread (ptid
, lwp
);
624 /* Start an inferior process and returns its pid.
625 ALLARGS is a vector of program-name and args. */
628 linux_create_inferior (char *program
, char **allargs
)
630 struct lwp_info
*new_lwp
;
633 struct cleanup
*restore_personality
634 = maybe_disable_address_space_randomization (disable_randomization
);
636 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
642 perror_with_name ("fork");
647 ptrace (PTRACE_TRACEME
, 0, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
649 #ifndef __ANDROID__ /* Bionic doesn't use SIGRTMIN the way glibc does. */
650 signal (__SIGRTMIN
+ 1, SIG_DFL
);
655 /* If gdbserver is connected to gdb via stdio, redirect the inferior's
656 stdout to stderr so that inferior i/o doesn't corrupt the connection.
657 Also, redirect stdin to /dev/null. */
658 if (remote_connection_is_stdio ())
661 open ("/dev/null", O_RDONLY
);
663 if (write (2, "stdin/stdout redirected\n",
664 sizeof ("stdin/stdout redirected\n") - 1) < 0)
666 /* Errors ignored. */;
670 execv (program
, allargs
);
672 execvp (program
, allargs
);
674 fprintf (stderr
, "Cannot exec %s: %s.\n", program
,
680 do_cleanups (restore_personality
);
682 linux_add_process (pid
, 0);
684 ptid
= ptid_build (pid
, pid
, 0);
685 new_lwp
= add_lwp (ptid
);
686 new_lwp
->must_set_ptrace_flags
= 1;
691 /* Attach to an inferior process. Returns 0 on success, ERRNO on
695 linux_attach_lwp (ptid_t ptid
)
697 struct lwp_info
*new_lwp
;
698 int lwpid
= ptid_get_lwp (ptid
);
700 if (ptrace (PTRACE_ATTACH
, lwpid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0)
704 new_lwp
= add_lwp (ptid
);
706 /* We need to wait for SIGSTOP before being able to make the next
707 ptrace call on this LWP. */
708 new_lwp
->must_set_ptrace_flags
= 1;
710 if (linux_proc_pid_is_stopped (lwpid
))
713 debug_printf ("Attached to a stopped process\n");
715 /* The process is definitely stopped. It is in a job control
716 stop, unless the kernel predates the TASK_STOPPED /
717 TASK_TRACED distinction, in which case it might be in a
718 ptrace stop. Make sure it is in a ptrace stop; from there we
719 can kill it, signal it, et cetera.
721 First make sure there is a pending SIGSTOP. Since we are
722 already attached, the process can not transition from stopped
723 to running without a PTRACE_CONT; so we know this signal will
724 go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
725 probably already in the queue (unless this kernel is old
726 enough to use TASK_STOPPED for ptrace stops); but since
727 SIGSTOP is not an RT signal, it can only be queued once. */
728 kill_lwp (lwpid
, SIGSTOP
);
730 /* Finally, resume the stopped process. This will deliver the
731 SIGSTOP (or a higher priority signal, just like normal
732 PTRACE_ATTACH), which we'll catch later on. */
733 ptrace (PTRACE_CONT
, lwpid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
736 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
739 There are several cases to consider here:
741 1) gdbserver has already attached to the process and is being notified
742 of a new thread that is being created.
743 In this case we should ignore that SIGSTOP and resume the
744 process. This is handled below by setting stop_expected = 1,
745 and the fact that add_thread sets last_resume_kind ==
748 2) This is the first thread (the process thread), and we're attaching
749 to it via attach_inferior.
750 In this case we want the process thread to stop.
751 This is handled by having linux_attach set last_resume_kind ==
752 resume_stop after we return.
754 If the pid we are attaching to is also the tgid, we attach to and
755 stop all the existing threads. Otherwise, we attach to pid and
756 ignore any other threads in the same group as this pid.
758 3) GDB is connecting to gdbserver and is requesting an enumeration of all
760 In this case we want the thread to stop.
761 FIXME: This case is currently not properly handled.
762 We should wait for the SIGSTOP but don't. Things work apparently
763 because enough time passes between when we ptrace (ATTACH) and when
764 gdb makes the next ptrace call on the thread.
766 On the other hand, if we are currently trying to stop all threads, we
767 should treat the new thread as if we had sent it a SIGSTOP. This works
768 because we are guaranteed that the add_lwp call above added us to the
769 end of the list, and so the new thread has not yet reached
770 wait_for_sigstop (but will). */
771 new_lwp
->stop_expected
= 1;
776 /* Callback for linux_proc_attach_tgid_threads. Attach to PTID if not
777 already attached. Returns true if a new LWP is found, false
781 attach_proc_task_lwp_callback (ptid_t ptid
)
783 /* Is this a new thread? */
784 if (find_thread_ptid (ptid
) == NULL
)
786 int lwpid
= ptid_get_lwp (ptid
);
790 debug_printf ("Found new lwp %d\n", lwpid
);
792 err
= linux_attach_lwp (ptid
);
794 /* Be quiet if we simply raced with the thread exiting. EPERM
795 is returned if the thread's task still exists, and is marked
796 as exited or zombie, as well as other conditions, so in that
797 case, confirm the status in /proc/PID/status. */
799 || (err
== EPERM
&& linux_proc_pid_is_gone (lwpid
)))
803 debug_printf ("Cannot attach to lwp %d: "
804 "thread is gone (%d: %s)\n",
805 lwpid
, err
, strerror (err
));
810 warning (_("Cannot attach to lwp %d: %s"),
812 linux_ptrace_attach_fail_reason_string (ptid
, err
));
820 /* Attach to PID. If PID is the tgid, attach to it and all
824 linux_attach (unsigned long pid
)
826 ptid_t ptid
= ptid_build (pid
, pid
, 0);
829 /* Attach to PID. We will check for other threads
831 err
= linux_attach_lwp (ptid
);
833 error ("Cannot attach to process %ld: %s",
834 pid
, linux_ptrace_attach_fail_reason_string (ptid
, err
));
836 linux_add_process (pid
, 1);
840 struct thread_info
*thread
;
842 /* Don't ignore the initial SIGSTOP if we just attached to this
843 process. It will be collected by wait shortly. */
844 thread
= find_thread_ptid (ptid_build (pid
, pid
, 0));
845 thread
->last_resume_kind
= resume_stop
;
848 /* We must attach to every LWP. If /proc is mounted, use that to
849 find them now. On the one hand, the inferior may be using raw
850 clone instead of using pthreads. On the other hand, even if it
851 is using pthreads, GDB may not be connected yet (thread_db needs
852 to do symbol lookups, through qSymbol). Also, thread_db walks
853 structures in the inferior's address space to find the list of
854 threads/LWPs, and those structures may well be corrupted. Note
855 that once thread_db is loaded, we'll still use it to list threads
856 and associate pthread info with each LWP. */
857 linux_proc_attach_tgid_threads (pid
, attach_proc_task_lwp_callback
);
868 second_thread_of_pid_p (struct inferior_list_entry
*entry
, void *args
)
870 struct counter
*counter
= args
;
872 if (ptid_get_pid (entry
->id
) == counter
->pid
)
874 if (++counter
->count
> 1)
882 last_thread_of_process_p (int pid
)
884 struct counter counter
= { pid
, 0 };
886 return (find_inferior (&all_threads
,
887 second_thread_of_pid_p
, &counter
) == NULL
);
893 linux_kill_one_lwp (struct lwp_info
*lwp
)
895 struct thread_info
*thr
= get_lwp_thread (lwp
);
896 int pid
= lwpid_of (thr
);
898 /* PTRACE_KILL is unreliable. After stepping into a signal handler,
899 there is no signal context, and ptrace(PTRACE_KILL) (or
900 ptrace(PTRACE_CONT, SIGKILL), pretty much the same) acts like
901 ptrace(CONT, pid, 0,0) and just resumes the tracee. A better
902 alternative is to kill with SIGKILL. We only need one SIGKILL
903 per process, not one for each thread. But since we still support
904 linuxthreads, and we also support debugging programs using raw
905 clone without CLONE_THREAD, we send one for each thread. For
906 years, we used PTRACE_KILL only, so we're being a bit paranoid
907 about some old kernels where PTRACE_KILL might work better
908 (dubious if there are any such, but that's why it's paranoia), so
909 we try SIGKILL first, PTRACE_KILL second, and so we're fine
913 kill_lwp (pid
, SIGKILL
);
916 int save_errno
= errno
;
918 debug_printf ("LKL: kill_lwp (SIGKILL) %s, 0, 0 (%s)\n",
919 target_pid_to_str (ptid_of (thr
)),
920 save_errno
? strerror (save_errno
) : "OK");
924 ptrace (PTRACE_KILL
, pid
, (PTRACE_TYPE_ARG3
) 0, (PTRACE_TYPE_ARG4
) 0);
927 int save_errno
= errno
;
929 debug_printf ("LKL: PTRACE_KILL %s, 0, 0 (%s)\n",
930 target_pid_to_str (ptid_of (thr
)),
931 save_errno
? strerror (save_errno
) : "OK");
935 /* Kill LWP and wait for it to die. */
938 kill_wait_lwp (struct lwp_info
*lwp
)
940 struct thread_info
*thr
= get_lwp_thread (lwp
);
941 int pid
= ptid_get_pid (ptid_of (thr
));
942 int lwpid
= ptid_get_lwp (ptid_of (thr
));
947 debug_printf ("kwl: killing lwp %d, for pid: %d\n", lwpid
, pid
);
951 linux_kill_one_lwp (lwp
);
953 /* Make sure it died. Notes:
955 - The loop is most likely unnecessary.
957 - We don't use linux_wait_for_event as that could delete lwps
958 while we're iterating over them. We're not interested in
959 any pending status at this point, only in making sure all
960 wait status on the kernel side are collected until the
963 - We don't use __WALL here as the __WALL emulation relies on
964 SIGCHLD, and killing a stopped process doesn't generate
965 one, nor an exit status.
967 res
= my_waitpid (lwpid
, &wstat
, 0);
968 if (res
== -1 && errno
== ECHILD
)
969 res
= my_waitpid (lwpid
, &wstat
, __WCLONE
);
970 } while (res
> 0 && WIFSTOPPED (wstat
));
972 gdb_assert (res
> 0);
975 /* Callback for `find_inferior'. Kills an lwp of a given process,
976 except the leader. */
979 kill_one_lwp_callback (struct inferior_list_entry
*entry
, void *args
)
981 struct thread_info
*thread
= (struct thread_info
*) entry
;
982 struct lwp_info
*lwp
= get_thread_lwp (thread
);
983 int pid
= * (int *) args
;
985 if (ptid_get_pid (entry
->id
) != pid
)
988 /* We avoid killing the first thread here, because of a Linux kernel (at
989 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
990 the children get a chance to be reaped, it will remain a zombie
993 if (lwpid_of (thread
) == pid
)
996 debug_printf ("lkop: is last of process %s\n",
997 target_pid_to_str (entry
->id
));
1001 kill_wait_lwp (lwp
);
1006 linux_kill (int pid
)
1008 struct process_info
*process
;
1009 struct lwp_info
*lwp
;
1011 process
= find_process_pid (pid
);
1012 if (process
== NULL
)
1015 /* If we're killing a running inferior, make sure it is stopped
1016 first, as PTRACE_KILL will not work otherwise. */
1017 stop_all_lwps (0, NULL
);
1019 find_inferior (&all_threads
, kill_one_lwp_callback
, &pid
);
1021 /* See the comment in linux_kill_one_lwp. We did not kill the first
1022 thread in the list, so do so now. */
1023 lwp
= find_lwp_pid (pid_to_ptid (pid
));
1028 debug_printf ("lk_1: cannot find lwp for pid: %d\n",
1032 kill_wait_lwp (lwp
);
1034 the_target
->mourn (process
);
1036 /* Since we presently can only stop all lwps of all processes, we
1037 need to unstop lwps of other processes. */
1038 unstop_all_lwps (0, NULL
);
1042 /* Get pending signal of THREAD, for detaching purposes. This is the
1043 signal the thread last stopped for, which we need to deliver to the
1044 thread when detaching, otherwise, it'd be suppressed/lost. */
1047 get_detach_signal (struct thread_info
*thread
)
1049 enum gdb_signal signo
= GDB_SIGNAL_0
;
1051 struct lwp_info
*lp
= get_thread_lwp (thread
);
1053 if (lp
->status_pending_p
)
1054 status
= lp
->status_pending
;
1057 /* If the thread had been suspended by gdbserver, and it stopped
1058 cleanly, then it'll have stopped with SIGSTOP. But we don't
1059 want to deliver that SIGSTOP. */
1060 if (thread
->last_status
.kind
!= TARGET_WAITKIND_STOPPED
1061 || thread
->last_status
.value
.sig
== GDB_SIGNAL_0
)
1064 /* Otherwise, we may need to deliver the signal we
1066 status
= lp
->last_status
;
1069 if (!WIFSTOPPED (status
))
1072 debug_printf ("GPS: lwp %s hasn't stopped: no pending signal\n",
1073 target_pid_to_str (ptid_of (thread
)));
1077 /* Extended wait statuses aren't real SIGTRAPs. */
1078 if (WSTOPSIG (status
) == SIGTRAP
&& linux_is_extended_waitstatus (status
))
1081 debug_printf ("GPS: lwp %s had stopped with extended "
1082 "status: no pending signal\n",
1083 target_pid_to_str (ptid_of (thread
)));
1087 signo
= gdb_signal_from_host (WSTOPSIG (status
));
1089 if (program_signals_p
&& !program_signals
[signo
])
1092 debug_printf ("GPS: lwp %s had signal %s, but it is in nopass state\n",
1093 target_pid_to_str (ptid_of (thread
)),
1094 gdb_signal_to_string (signo
));
1097 else if (!program_signals_p
1098 /* If we have no way to know which signals GDB does not
1099 want to have passed to the program, assume
1100 SIGTRAP/SIGINT, which is GDB's default. */
1101 && (signo
== GDB_SIGNAL_TRAP
|| signo
== GDB_SIGNAL_INT
))
1104 debug_printf ("GPS: lwp %s had signal %s, "
1105 "but we don't know if we should pass it. "
1106 "Default to not.\n",
1107 target_pid_to_str (ptid_of (thread
)),
1108 gdb_signal_to_string (signo
));
1114 debug_printf ("GPS: lwp %s has pending signal %s: delivering it.\n",
1115 target_pid_to_str (ptid_of (thread
)),
1116 gdb_signal_to_string (signo
));
1118 return WSTOPSIG (status
);
1123 linux_detach_one_lwp (struct inferior_list_entry
*entry
, void *args
)
1125 struct thread_info
*thread
= (struct thread_info
*) entry
;
1126 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1127 int pid
= * (int *) args
;
1130 if (ptid_get_pid (entry
->id
) != pid
)
1133 /* If there is a pending SIGSTOP, get rid of it. */
1134 if (lwp
->stop_expected
)
1137 debug_printf ("Sending SIGCONT to %s\n",
1138 target_pid_to_str (ptid_of (thread
)));
1140 kill_lwp (lwpid_of (thread
), SIGCONT
);
1141 lwp
->stop_expected
= 0;
1144 /* Flush any pending changes to the process's registers. */
1145 regcache_invalidate_thread (thread
);
1147 /* Pass on any pending signal for this thread. */
1148 sig
= get_detach_signal (thread
);
1150 /* Finally, let it resume. */
1151 if (the_low_target
.prepare_to_resume
!= NULL
)
1152 the_low_target
.prepare_to_resume (lwp
);
1153 if (ptrace (PTRACE_DETACH
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
1154 (PTRACE_TYPE_ARG4
) (long) sig
) < 0)
1155 error (_("Can't detach %s: %s"),
1156 target_pid_to_str (ptid_of (thread
)),
1164 linux_detach (int pid
)
1166 struct process_info
*process
;
1168 process
= find_process_pid (pid
);
1169 if (process
== NULL
)
1172 /* Stop all threads before detaching. First, ptrace requires that
1173 the thread is stopped to sucessfully detach. Second, thread_db
1174 may need to uninstall thread event breakpoints from memory, which
1175 only works with a stopped process anyway. */
1176 stop_all_lwps (0, NULL
);
1178 #ifdef USE_THREAD_DB
1179 thread_db_detach (process
);
1182 /* Stabilize threads (move out of jump pads). */
1183 stabilize_threads ();
1185 find_inferior (&all_threads
, linux_detach_one_lwp
, &pid
);
1187 the_target
->mourn (process
);
1189 /* Since we presently can only stop all lwps of all processes, we
1190 need to unstop lwps of other processes. */
1191 unstop_all_lwps (0, NULL
);
1195 /* Remove all LWPs that belong to process PROC from the lwp list. */
1198 delete_lwp_callback (struct inferior_list_entry
*entry
, void *proc
)
1200 struct thread_info
*thread
= (struct thread_info
*) entry
;
1201 struct lwp_info
*lwp
= get_thread_lwp (thread
);
1202 struct process_info
*process
= proc
;
1204 if (pid_of (thread
) == pid_of (process
))
1211 linux_mourn (struct process_info
*process
)
1213 struct process_info_private
*priv
;
1215 #ifdef USE_THREAD_DB
1216 thread_db_mourn (process
);
1219 find_inferior (&all_threads
, delete_lwp_callback
, process
);
1221 /* Freeing all private data. */
1222 priv
= process
->priv
;
1223 free (priv
->arch_private
);
1225 process
->priv
= NULL
;
1227 remove_process (process
);
1231 linux_join (int pid
)
1236 ret
= my_waitpid (pid
, &status
, 0);
1237 if (WIFEXITED (status
) || WIFSIGNALED (status
))
1239 } while (ret
!= -1 || errno
!= ECHILD
);
1242 /* Return nonzero if the given thread is still alive. */
1244 linux_thread_alive (ptid_t ptid
)
1246 struct lwp_info
*lwp
= find_lwp_pid (ptid
);
1248 /* We assume we always know if a thread exits. If a whole process
1249 exited but we still haven't been able to report it to GDB, we'll
1250 hold on to the last lwp of the dead process. */
1257 /* Return 1 if this lwp still has an interesting status pending. If
1258 not (e.g., it had stopped for a breakpoint that is gone), return
1262 thread_still_has_status_pending_p (struct thread_info
*thread
)
1264 struct lwp_info
*lp
= get_thread_lwp (thread
);
1266 if (!lp
->status_pending_p
)
1269 /* If we got a `vCont;t', but we haven't reported a stop yet, do
1270 report any status pending the LWP may have. */
1271 if (thread
->last_resume_kind
== resume_stop
1272 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
1275 if (thread
->last_resume_kind
!= resume_stop
1276 && (lp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
1277 || lp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
1279 struct thread_info
*saved_thread
;
1283 gdb_assert (lp
->last_status
!= 0);
1287 saved_thread
= current_thread
;
1288 current_thread
= thread
;
1290 if (pc
!= lp
->stop_pc
)
1293 debug_printf ("PC of %ld changed\n",
1298 #if !USE_SIGTRAP_SIGINFO
1299 else if (lp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
1300 && !(*the_low_target
.breakpoint_at
) (pc
))
1303 debug_printf ("previous SW breakpoint of %ld gone\n",
1307 else if (lp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
1308 && !hardware_breakpoint_inserted_here (pc
))
1311 debug_printf ("previous HW breakpoint of %ld gone\n",
1317 current_thread
= saved_thread
;
1322 debug_printf ("discarding pending breakpoint status\n");
1323 lp
->status_pending_p
= 0;
1331 /* Return 1 if this lwp has an interesting status pending. */
1333 status_pending_p_callback (struct inferior_list_entry
*entry
, void *arg
)
1335 struct thread_info
*thread
= (struct thread_info
*) entry
;
1336 struct lwp_info
*lp
= get_thread_lwp (thread
);
1337 ptid_t ptid
= * (ptid_t
*) arg
;
1339 /* Check if we're only interested in events from a specific process
1340 or a specific LWP. */
1341 if (!ptid_match (ptid_of (thread
), ptid
))
1344 if (lp
->status_pending_p
1345 && !thread_still_has_status_pending_p (thread
))
1347 linux_resume_one_lwp (lp
, lp
->stepping
, GDB_SIGNAL_0
, NULL
);
1351 return lp
->status_pending_p
;
1355 same_lwp (struct inferior_list_entry
*entry
, void *data
)
1357 ptid_t ptid
= *(ptid_t
*) data
;
1360 if (ptid_get_lwp (ptid
) != 0)
1361 lwp
= ptid_get_lwp (ptid
);
1363 lwp
= ptid_get_pid (ptid
);
1365 if (ptid_get_lwp (entry
->id
) == lwp
)
1372 find_lwp_pid (ptid_t ptid
)
1374 struct inferior_list_entry
*thread
1375 = find_inferior (&all_threads
, same_lwp
, &ptid
);
1380 return get_thread_lwp ((struct thread_info
*) thread
);
1383 /* Return the number of known LWPs in the tgid given by PID. */
1388 struct inferior_list_entry
*inf
, *tmp
;
1391 ALL_INFERIORS (&all_threads
, inf
, tmp
)
1393 if (ptid_get_pid (inf
->id
) == pid
)
1400 /* Detect zombie thread group leaders, and "exit" them. We can't reap
1401 their exits until all other threads in the group have exited. */
1404 check_zombie_leaders (void)
1406 struct process_info
*proc
, *tmp
;
1408 ALL_PROCESSES (proc
, tmp
)
1410 pid_t leader_pid
= pid_of (proc
);
1411 struct lwp_info
*leader_lp
;
1413 leader_lp
= find_lwp_pid (pid_to_ptid (leader_pid
));
1416 debug_printf ("leader_pid=%d, leader_lp!=NULL=%d, "
1417 "num_lwps=%d, zombie=%d\n",
1418 leader_pid
, leader_lp
!= NULL
, num_lwps (leader_pid
),
1419 linux_proc_pid_is_zombie (leader_pid
));
1421 if (leader_lp
!= NULL
1422 /* Check if there are other threads in the group, as we may
1423 have raced with the inferior simply exiting. */
1424 && !last_thread_of_process_p (leader_pid
)
1425 && linux_proc_pid_is_zombie (leader_pid
))
1427 /* A leader zombie can mean one of two things:
1429 - It exited, and there's an exit status pending
1430 available, or only the leader exited (not the whole
1431 program). In the latter case, we can't waitpid the
1432 leader's exit status until all other threads are gone.
1434 - There are 3 or more threads in the group, and a thread
1435 other than the leader exec'd. On an exec, the Linux
1436 kernel destroys all other threads (except the execing
1437 one) in the thread group, and resets the execing thread's
1438 tid to the tgid. No exit notification is sent for the
1439 execing thread -- from the ptracer's perspective, it
1440 appears as though the execing thread just vanishes.
1441 Until we reap all other threads except the leader and the
1442 execing thread, the leader will be zombie, and the
1443 execing thread will be in `D (disc sleep)'. As soon as
1444 all other threads are reaped, the execing thread changes
1445 it's tid to the tgid, and the previous (zombie) leader
1446 vanishes, giving place to the "new" leader. We could try
1447 distinguishing the exit and exec cases, by waiting once
1448 more, and seeing if something comes out, but it doesn't
1449 sound useful. The previous leader _does_ go away, and
1450 we'll re-add the new one once we see the exec event
1451 (which is just the same as what would happen if the
1452 previous leader did exit voluntarily before some other
1457 "CZL: Thread group leader %d zombie "
1458 "(it exited, or another thread execd).\n",
1461 delete_lwp (leader_lp
);
1466 /* Callback for `find_inferior'. Returns the first LWP that is not
1467 stopped. ARG is a PTID filter. */
1470 not_stopped_callback (struct inferior_list_entry
*entry
, void *arg
)
1472 struct thread_info
*thr
= (struct thread_info
*) entry
;
1473 struct lwp_info
*lwp
;
1474 ptid_t filter
= *(ptid_t
*) arg
;
1476 if (!ptid_match (ptid_of (thr
), filter
))
1479 lwp
= get_thread_lwp (thr
);
1486 /* This function should only be called if the LWP got a SIGTRAP.
1488 Handle any tracepoint steps or hits. Return true if a tracepoint
1489 event was handled, 0 otherwise. */
1492 handle_tracepoints (struct lwp_info
*lwp
)
1494 struct thread_info
*tinfo
= get_lwp_thread (lwp
);
1495 int tpoint_related_event
= 0;
1497 gdb_assert (lwp
->suspended
== 0);
1499 /* If this tracepoint hit causes a tracing stop, we'll immediately
1500 uninsert tracepoints. To do this, we temporarily pause all
1501 threads, unpatch away, and then unpause threads. We need to make
1502 sure the unpausing doesn't resume LWP too. */
1505 /* And we need to be sure that any all-threads-stopping doesn't try
1506 to move threads out of the jump pads, as it could deadlock the
1507 inferior (LWP could be in the jump pad, maybe even holding the
1510 /* Do any necessary step collect actions. */
1511 tpoint_related_event
|= tracepoint_finished_step (tinfo
, lwp
->stop_pc
);
1513 tpoint_related_event
|= handle_tracepoint_bkpts (tinfo
, lwp
->stop_pc
);
1515 /* See if we just hit a tracepoint and do its main collect
1517 tpoint_related_event
|= tracepoint_was_hit (tinfo
, lwp
->stop_pc
);
1521 gdb_assert (lwp
->suspended
== 0);
1522 gdb_assert (!stabilizing_threads
|| lwp
->collecting_fast_tracepoint
);
1524 if (tpoint_related_event
)
1527 debug_printf ("got a tracepoint event\n");
1534 /* Convenience wrapper. Returns true if LWP is presently collecting a
1538 linux_fast_tracepoint_collecting (struct lwp_info
*lwp
,
1539 struct fast_tpoint_collect_status
*status
)
1541 CORE_ADDR thread_area
;
1542 struct thread_info
*thread
= get_lwp_thread (lwp
);
1544 if (the_low_target
.get_thread_area
== NULL
)
1547 /* Get the thread area address. This is used to recognize which
1548 thread is which when tracing with the in-process agent library.
1549 We don't read anything from the address, and treat it as opaque;
1550 it's the address itself that we assume is unique per-thread. */
1551 if ((*the_low_target
.get_thread_area
) (lwpid_of (thread
), &thread_area
) == -1)
1554 return fast_tracepoint_collecting (thread_area
, lwp
->stop_pc
, status
);
1557 /* The reason we resume in the caller, is because we want to be able
1558 to pass lwp->status_pending as WSTAT, and we need to clear
1559 status_pending_p before resuming, otherwise, linux_resume_one_lwp
1560 refuses to resume. */
1563 maybe_move_out_of_jump_pad (struct lwp_info
*lwp
, int *wstat
)
1565 struct thread_info
*saved_thread
;
1567 saved_thread
= current_thread
;
1568 current_thread
= get_lwp_thread (lwp
);
1571 || (WIFSTOPPED (*wstat
) && WSTOPSIG (*wstat
) != SIGTRAP
))
1572 && supports_fast_tracepoints ()
1573 && agent_loaded_p ())
1575 struct fast_tpoint_collect_status status
;
1579 debug_printf ("Checking whether LWP %ld needs to move out of the "
1581 lwpid_of (current_thread
));
1583 r
= linux_fast_tracepoint_collecting (lwp
, &status
);
1586 || (WSTOPSIG (*wstat
) != SIGILL
1587 && WSTOPSIG (*wstat
) != SIGFPE
1588 && WSTOPSIG (*wstat
) != SIGSEGV
1589 && WSTOPSIG (*wstat
) != SIGBUS
))
1591 lwp
->collecting_fast_tracepoint
= r
;
1595 if (r
== 1 && lwp
->exit_jump_pad_bkpt
== NULL
)
1597 /* Haven't executed the original instruction yet.
1598 Set breakpoint there, and wait till it's hit,
1599 then single-step until exiting the jump pad. */
1600 lwp
->exit_jump_pad_bkpt
1601 = set_breakpoint_at (status
.adjusted_insn_addr
, NULL
);
1605 debug_printf ("Checking whether LWP %ld needs to move out of "
1606 "the jump pad...it does\n",
1607 lwpid_of (current_thread
));
1608 current_thread
= saved_thread
;
1615 /* If we get a synchronous signal while collecting, *and*
1616 while executing the (relocated) original instruction,
1617 reset the PC to point at the tpoint address, before
1618 reporting to GDB. Otherwise, it's an IPA lib bug: just
1619 report the signal to GDB, and pray for the best. */
1621 lwp
->collecting_fast_tracepoint
= 0;
1624 && (status
.adjusted_insn_addr
<= lwp
->stop_pc
1625 && lwp
->stop_pc
< status
.adjusted_insn_addr_end
))
1628 struct regcache
*regcache
;
1630 /* The si_addr on a few signals references the address
1631 of the faulting instruction. Adjust that as
1633 if ((WSTOPSIG (*wstat
) == SIGILL
1634 || WSTOPSIG (*wstat
) == SIGFPE
1635 || WSTOPSIG (*wstat
) == SIGBUS
1636 || WSTOPSIG (*wstat
) == SIGSEGV
)
1637 && ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
1638 (PTRACE_TYPE_ARG3
) 0, &info
) == 0
1639 /* Final check just to make sure we don't clobber
1640 the siginfo of non-kernel-sent signals. */
1641 && (uintptr_t) info
.si_addr
== lwp
->stop_pc
)
1643 info
.si_addr
= (void *) (uintptr_t) status
.tpoint_addr
;
1644 ptrace (PTRACE_SETSIGINFO
, lwpid_of (current_thread
),
1645 (PTRACE_TYPE_ARG3
) 0, &info
);
1648 regcache
= get_thread_regcache (current_thread
, 1);
1649 (*the_low_target
.set_pc
) (regcache
, status
.tpoint_addr
);
1650 lwp
->stop_pc
= status
.tpoint_addr
;
1652 /* Cancel any fast tracepoint lock this thread was
1654 force_unlock_trace_buffer ();
1657 if (lwp
->exit_jump_pad_bkpt
!= NULL
)
1660 debug_printf ("Cancelling fast exit-jump-pad: removing bkpt. "
1661 "stopping all threads momentarily.\n");
1663 stop_all_lwps (1, lwp
);
1665 delete_breakpoint (lwp
->exit_jump_pad_bkpt
);
1666 lwp
->exit_jump_pad_bkpt
= NULL
;
1668 unstop_all_lwps (1, lwp
);
1670 gdb_assert (lwp
->suspended
>= 0);
1676 debug_printf ("Checking whether LWP %ld needs to move out of the "
1678 lwpid_of (current_thread
));
1680 current_thread
= saved_thread
;
1684 /* Enqueue one signal in the "signals to report later when out of the
1688 enqueue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
1690 struct pending_signals
*p_sig
;
1691 struct thread_info
*thread
= get_lwp_thread (lwp
);
1694 debug_printf ("Deferring signal %d for LWP %ld.\n",
1695 WSTOPSIG (*wstat
), lwpid_of (thread
));
1699 struct pending_signals
*sig
;
1701 for (sig
= lwp
->pending_signals_to_report
;
1704 debug_printf (" Already queued %d\n",
1707 debug_printf (" (no more currently queued signals)\n");
1710 /* Don't enqueue non-RT signals if they are already in the deferred
1711 queue. (SIGSTOP being the easiest signal to see ending up here
1713 if (WSTOPSIG (*wstat
) < __SIGRTMIN
)
1715 struct pending_signals
*sig
;
1717 for (sig
= lwp
->pending_signals_to_report
;
1721 if (sig
->signal
== WSTOPSIG (*wstat
))
1724 debug_printf ("Not requeuing already queued non-RT signal %d"
1733 p_sig
= xmalloc (sizeof (*p_sig
));
1734 p_sig
->prev
= lwp
->pending_signals_to_report
;
1735 p_sig
->signal
= WSTOPSIG (*wstat
);
1736 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
1737 ptrace (PTRACE_GETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
1740 lwp
->pending_signals_to_report
= p_sig
;
1743 /* Dequeue one signal from the "signals to report later when out of
1744 the jump pad" list. */
1747 dequeue_one_deferred_signal (struct lwp_info
*lwp
, int *wstat
)
1749 struct thread_info
*thread
= get_lwp_thread (lwp
);
1751 if (lwp
->pending_signals_to_report
!= NULL
)
1753 struct pending_signals
**p_sig
;
1755 p_sig
= &lwp
->pending_signals_to_report
;
1756 while ((*p_sig
)->prev
!= NULL
)
1757 p_sig
= &(*p_sig
)->prev
;
1759 *wstat
= W_STOPCODE ((*p_sig
)->signal
);
1760 if ((*p_sig
)->info
.si_signo
!= 0)
1761 ptrace (PTRACE_SETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
1767 debug_printf ("Reporting deferred signal %d for LWP %ld.\n",
1768 WSTOPSIG (*wstat
), lwpid_of (thread
));
1772 struct pending_signals
*sig
;
1774 for (sig
= lwp
->pending_signals_to_report
;
1777 debug_printf (" Still queued %d\n",
1780 debug_printf (" (no more queued signals)\n");
1789 /* Fetch the possibly triggered data watchpoint info and store it in
1792 On some archs, like x86, that use debug registers to set
1793 watchpoints, it's possible that the way to know which watched
1794 address trapped, is to check the register that is used to select
1795 which address to watch. Problem is, between setting the watchpoint
1796 and reading back which data address trapped, the user may change
1797 the set of watchpoints, and, as a consequence, GDB changes the
1798 debug registers in the inferior. To avoid reading back a stale
1799 stopped-data-address when that happens, we cache in LP the fact
1800 that a watchpoint trapped, and the corresponding data address, as
1801 soon as we see CHILD stop with a SIGTRAP. If GDB changes the debug
1802 registers meanwhile, we have the cached data we can rely on. */
1805 check_stopped_by_watchpoint (struct lwp_info
*child
)
1807 if (the_low_target
.stopped_by_watchpoint
!= NULL
)
1809 struct thread_info
*saved_thread
;
1811 saved_thread
= current_thread
;
1812 current_thread
= get_lwp_thread (child
);
1814 if (the_low_target
.stopped_by_watchpoint ())
1816 child
->stop_reason
= TARGET_STOPPED_BY_WATCHPOINT
;
1818 if (the_low_target
.stopped_data_address
!= NULL
)
1819 child
->stopped_data_address
1820 = the_low_target
.stopped_data_address ();
1822 child
->stopped_data_address
= 0;
1825 current_thread
= saved_thread
;
1828 return child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
;
1831 /* Do low-level handling of the event, and check if we should go on
1832 and pass it to caller code. Return the affected lwp if we are, or
1835 static struct lwp_info
*
1836 linux_low_filter_event (int lwpid
, int wstat
)
1838 struct lwp_info
*child
;
1839 struct thread_info
*thread
;
1840 int have_stop_pc
= 0;
1842 child
= find_lwp_pid (pid_to_ptid (lwpid
));
1844 /* If we didn't find a process, one of two things presumably happened:
1845 - A process we started and then detached from has exited. Ignore it.
1846 - A process we are controlling has forked and the new child's stop
1847 was reported to us by the kernel. Save its PID. */
1848 if (child
== NULL
&& WIFSTOPPED (wstat
))
1850 add_to_pid_list (&stopped_pids
, lwpid
, wstat
);
1853 else if (child
== NULL
)
1856 thread
= get_lwp_thread (child
);
1860 child
->last_status
= wstat
;
1862 /* Check if the thread has exited. */
1863 if ((WIFEXITED (wstat
) || WIFSIGNALED (wstat
)))
1866 debug_printf ("LLFE: %d exited.\n", lwpid
);
1867 if (num_lwps (pid_of (thread
)) > 1)
1870 /* If there is at least one more LWP, then the exit signal was
1871 not the end of the debugged application and should be
1878 /* This was the last lwp in the process. Since events are
1879 serialized to GDB core, and we can't report this one
1880 right now, but GDB core and the other target layers will
1881 want to be notified about the exit code/signal, leave the
1882 status pending for the next time we're able to report
1884 mark_lwp_dead (child
, wstat
);
1889 gdb_assert (WIFSTOPPED (wstat
));
1891 if (WIFSTOPPED (wstat
))
1893 struct process_info
*proc
;
1895 /* Architecture-specific setup after inferior is running. This
1896 needs to happen after we have attached to the inferior and it
1897 is stopped for the first time, but before we access any
1898 inferior registers. */
1899 proc
= find_process_pid (pid_of (thread
));
1900 if (proc
->priv
->new_inferior
)
1902 struct thread_info
*saved_thread
;
1904 saved_thread
= current_thread
;
1905 current_thread
= thread
;
1907 the_low_target
.arch_setup ();
1909 current_thread
= saved_thread
;
1911 proc
->priv
->new_inferior
= 0;
1915 if (WIFSTOPPED (wstat
) && child
->must_set_ptrace_flags
)
1917 struct process_info
*proc
= find_process_pid (pid_of (thread
));
1919 linux_enable_event_reporting (lwpid
, proc
->attached
);
1920 child
->must_set_ptrace_flags
= 0;
1923 /* Be careful to not overwrite stop_pc until
1924 check_stopped_by_breakpoint is called. */
1925 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGTRAP
1926 && linux_is_extended_waitstatus (wstat
))
1928 child
->stop_pc
= get_pc (child
);
1929 handle_extended_wait (child
, wstat
);
1933 /* Check first whether this was a SW/HW breakpoint before checking
1934 watchpoints, because at least s390 can't tell the data address of
1935 hardware watchpoint hits, and returns stopped-by-watchpoint as
1936 long as there's a watchpoint set. */
1937 if (WIFSTOPPED (wstat
) && linux_wstatus_maybe_breakpoint (wstat
))
1939 if (check_stopped_by_breakpoint (child
))
1943 /* Note that TRAP_HWBKPT can indicate either a hardware breakpoint
1944 or hardware watchpoint. Check which is which if we got
1945 TARGET_STOPPED_BY_HW_BREAKPOINT. */
1946 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGTRAP
1947 && (child
->stop_reason
== TARGET_STOPPED_BY_NO_REASON
1948 || child
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
))
1949 check_stopped_by_watchpoint (child
);
1952 child
->stop_pc
= get_pc (child
);
1954 if (WIFSTOPPED (wstat
) && WSTOPSIG (wstat
) == SIGSTOP
1955 && child
->stop_expected
)
1958 debug_printf ("Expected stop.\n");
1959 child
->stop_expected
= 0;
1961 if (thread
->last_resume_kind
== resume_stop
)
1963 /* We want to report the stop to the core. Treat the
1964 SIGSTOP as a normal event. */
1966 else if (stopping_threads
!= NOT_STOPPING_THREADS
)
1968 /* Stopping threads. We don't want this SIGSTOP to end up
1974 /* Filter out the event. */
1975 linux_resume_one_lwp (child
, child
->stepping
, 0, NULL
);
1980 child
->status_pending_p
= 1;
1981 child
->status_pending
= wstat
;
1985 /* Resume LWPs that are currently stopped without any pending status
1986 to report, but are resumed from the core's perspective. */
1989 resume_stopped_resumed_lwps (struct inferior_list_entry
*entry
)
1991 struct thread_info
*thread
= (struct thread_info
*) entry
;
1992 struct lwp_info
*lp
= get_thread_lwp (thread
);
1995 && !lp
->status_pending_p
1996 && thread
->last_resume_kind
!= resume_stop
1997 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
)
1999 int step
= thread
->last_resume_kind
== resume_step
;
2002 debug_printf ("RSRL: resuming stopped-resumed LWP %s at %s: step=%d\n",
2003 target_pid_to_str (ptid_of (thread
)),
2004 paddress (lp
->stop_pc
),
2007 linux_resume_one_lwp (lp
, step
, GDB_SIGNAL_0
, NULL
);
2011 /* Wait for an event from child(ren) WAIT_PTID, and return any that
2012 match FILTER_PTID (leaving others pending). The PTIDs can be:
2013 minus_one_ptid, to specify any child; a pid PTID, specifying all
2014 lwps of a thread group; or a PTID representing a single lwp. Store
2015 the stop status through the status pointer WSTAT. OPTIONS is
2016 passed to the waitpid call. Return 0 if no event was found and
2017 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
2018 was found. Return the PID of the stopped child otherwise. */
2021 linux_wait_for_event_filtered (ptid_t wait_ptid
, ptid_t filter_ptid
,
2022 int *wstatp
, int options
)
2024 struct thread_info
*event_thread
;
2025 struct lwp_info
*event_child
, *requested_child
;
2026 sigset_t block_mask
, prev_mask
;
2029 /* N.B. event_thread points to the thread_info struct that contains
2030 event_child. Keep them in sync. */
2031 event_thread
= NULL
;
2033 requested_child
= NULL
;
2035 /* Check for a lwp with a pending status. */
2037 if (ptid_equal (filter_ptid
, minus_one_ptid
) || ptid_is_pid (filter_ptid
))
2039 event_thread
= (struct thread_info
*)
2040 find_inferior (&all_threads
, status_pending_p_callback
, &filter_ptid
);
2041 if (event_thread
!= NULL
)
2042 event_child
= get_thread_lwp (event_thread
);
2043 if (debug_threads
&& event_thread
)
2044 debug_printf ("Got a pending child %ld\n", lwpid_of (event_thread
));
2046 else if (!ptid_equal (filter_ptid
, null_ptid
))
2048 requested_child
= find_lwp_pid (filter_ptid
);
2050 if (stopping_threads
== NOT_STOPPING_THREADS
2051 && requested_child
->status_pending_p
2052 && requested_child
->collecting_fast_tracepoint
)
2054 enqueue_one_deferred_signal (requested_child
,
2055 &requested_child
->status_pending
);
2056 requested_child
->status_pending_p
= 0;
2057 requested_child
->status_pending
= 0;
2058 linux_resume_one_lwp (requested_child
, 0, 0, NULL
);
2061 if (requested_child
->suspended
2062 && requested_child
->status_pending_p
)
2064 internal_error (__FILE__
, __LINE__
,
2065 "requesting an event out of a"
2066 " suspended child?");
2069 if (requested_child
->status_pending_p
)
2071 event_child
= requested_child
;
2072 event_thread
= get_lwp_thread (event_child
);
2076 if (event_child
!= NULL
)
2079 debug_printf ("Got an event from pending child %ld (%04x)\n",
2080 lwpid_of (event_thread
), event_child
->status_pending
);
2081 *wstatp
= event_child
->status_pending
;
2082 event_child
->status_pending_p
= 0;
2083 event_child
->status_pending
= 0;
2084 current_thread
= event_thread
;
2085 return lwpid_of (event_thread
);
2088 /* But if we don't find a pending event, we'll have to wait.
2090 We only enter this loop if no process has a pending wait status.
2091 Thus any action taken in response to a wait status inside this
2092 loop is responding as soon as we detect the status, not after any
2095 /* Make sure SIGCHLD is blocked until the sigsuspend below. Block
2096 all signals while here. */
2097 sigfillset (&block_mask
);
2098 sigprocmask (SIG_BLOCK
, &block_mask
, &prev_mask
);
2100 /* Always pull all events out of the kernel. We'll randomly select
2101 an event LWP out of all that have events, to prevent
2103 while (event_child
== NULL
)
2107 /* Always use -1 and WNOHANG, due to couple of a kernel/ptrace
2110 - If the thread group leader exits while other threads in the
2111 thread group still exist, waitpid(TGID, ...) hangs. That
2112 waitpid won't return an exit status until the other threads
2113 in the group are reaped.
2115 - When a non-leader thread execs, that thread just vanishes
2116 without reporting an exit (so we'd hang if we waited for it
2117 explicitly in that case). The exec event is reported to
2118 the TGID pid (although we don't currently enable exec
2121 ret
= my_waitpid (-1, wstatp
, options
| WNOHANG
);
2124 debug_printf ("LWFE: waitpid(-1, ...) returned %d, %s\n",
2125 ret
, errno
? strerror (errno
) : "ERRNO-OK");
2131 debug_printf ("LLW: waitpid %ld received %s\n",
2132 (long) ret
, status_to_str (*wstatp
));
2135 /* Filter all events. IOW, leave all events pending. We'll
2136 randomly select an event LWP out of all that have events
2138 linux_low_filter_event (ret
, *wstatp
);
2139 /* Retry until nothing comes out of waitpid. A single
2140 SIGCHLD can indicate more than one child stopped. */
2144 /* Now that we've pulled all events out of the kernel, resume
2145 LWPs that don't have an interesting event to report. */
2146 if (stopping_threads
== NOT_STOPPING_THREADS
)
2147 for_each_inferior (&all_threads
, resume_stopped_resumed_lwps
);
2149 /* ... and find an LWP with a status to report to the core, if
2151 event_thread
= (struct thread_info
*)
2152 find_inferior (&all_threads
, status_pending_p_callback
, &filter_ptid
);
2153 if (event_thread
!= NULL
)
2155 event_child
= get_thread_lwp (event_thread
);
2156 *wstatp
= event_child
->status_pending
;
2157 event_child
->status_pending_p
= 0;
2158 event_child
->status_pending
= 0;
2162 /* Check for zombie thread group leaders. Those can't be reaped
2163 until all other threads in the thread group are. */
2164 check_zombie_leaders ();
2166 /* If there are no resumed children left in the set of LWPs we
2167 want to wait for, bail. We can't just block in
2168 waitpid/sigsuspend, because lwps might have been left stopped
2169 in trace-stop state, and we'd be stuck forever waiting for
2170 their status to change (which would only happen if we resumed
2171 them). Even if WNOHANG is set, this return code is preferred
2172 over 0 (below), as it is more detailed. */
2173 if ((find_inferior (&all_threads
,
2174 not_stopped_callback
,
2175 &wait_ptid
) == NULL
))
2178 debug_printf ("LLW: exit (no unwaited-for LWP)\n");
2179 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2183 /* No interesting event to report to the caller. */
2184 if ((options
& WNOHANG
))
2187 debug_printf ("WNOHANG set, no event found\n");
2189 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2193 /* Block until we get an event reported with SIGCHLD. */
2195 debug_printf ("sigsuspend'ing\n");
2197 sigsuspend (&prev_mask
);
2198 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2202 sigprocmask (SIG_SETMASK
, &prev_mask
, NULL
);
2204 current_thread
= event_thread
;
2206 /* Check for thread exit. */
2207 if (! WIFSTOPPED (*wstatp
))
2209 gdb_assert (last_thread_of_process_p (pid_of (event_thread
)));
2212 debug_printf ("LWP %d is the last lwp of process. "
2213 "Process %ld exiting.\n",
2214 pid_of (event_thread
), lwpid_of (event_thread
));
2215 return lwpid_of (event_thread
);
2218 return lwpid_of (event_thread
);
2221 /* Wait for an event from child(ren) PTID. PTIDs can be:
2222 minus_one_ptid, to specify any child; a pid PTID, specifying all
2223 lwps of a thread group; or a PTID representing a single lwp. Store
2224 the stop status through the status pointer WSTAT. OPTIONS is
2225 passed to the waitpid call. Return 0 if no event was found and
2226 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
2227 was found. Return the PID of the stopped child otherwise. */
2230 linux_wait_for_event (ptid_t ptid
, int *wstatp
, int options
)
2232 return linux_wait_for_event_filtered (ptid
, ptid
, wstatp
, options
);
2235 /* Count the LWP's that have had events. */
2238 count_events_callback (struct inferior_list_entry
*entry
, void *data
)
2240 struct thread_info
*thread
= (struct thread_info
*) entry
;
2243 gdb_assert (count
!= NULL
);
2245 /* Count only resumed LWPs that have an event pending. */
2246 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2247 && thread
->last_resume_kind
!= resume_stop
2248 && thread
->status_pending_p
)
2254 /* Select the LWP (if any) that is currently being single-stepped. */
2257 select_singlestep_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
2259 struct thread_info
*thread
= (struct thread_info
*) entry
;
2260 struct lwp_info
*lp
= get_thread_lwp (thread
);
2262 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2263 && thread
->last_resume_kind
== resume_step
2264 && lp
->status_pending_p
)
2270 /* Select the Nth LWP that has had a SIGTRAP event that should be
2274 select_event_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
2276 struct thread_info
*thread
= (struct thread_info
*) entry
;
2277 int *selector
= data
;
2279 gdb_assert (selector
!= NULL
);
2281 /* Select only resumed LWPs that have an event pending. */
2282 if (thread
->last_resume_kind
!= resume_stop
2283 && thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2284 && thread
->status_pending_p
)
2285 if ((*selector
)-- == 0)
2291 /* Select one LWP out of those that have events pending. */
2294 select_event_lwp (struct lwp_info
**orig_lp
)
2297 int random_selector
;
2298 struct thread_info
*event_thread
= NULL
;
2300 /* In all-stop, give preference to the LWP that is being
2301 single-stepped. There will be at most one, and it's the LWP that
2302 the core is most interested in. If we didn't do this, then we'd
2303 have to handle pending step SIGTRAPs somehow in case the core
2304 later continues the previously-stepped thread, otherwise we'd
2305 report the pending SIGTRAP, and the core, not having stepped the
2306 thread, wouldn't understand what the trap was for, and therefore
2307 would report it to the user as a random signal. */
2311 = (struct thread_info
*) find_inferior (&all_threads
,
2312 select_singlestep_lwp_callback
,
2314 if (event_thread
!= NULL
)
2317 debug_printf ("SEL: Select single-step %s\n",
2318 target_pid_to_str (ptid_of (event_thread
)));
2321 if (event_thread
== NULL
)
2323 /* No single-stepping LWP. Select one at random, out of those
2324 which have had SIGTRAP events. */
2326 /* First see how many SIGTRAP events we have. */
2327 find_inferior (&all_threads
, count_events_callback
, &num_events
);
2329 /* Now randomly pick a LWP out of those that have had a SIGTRAP. */
2330 random_selector
= (int)
2331 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
2333 if (debug_threads
&& num_events
> 1)
2334 debug_printf ("SEL: Found %d SIGTRAP events, selecting #%d\n",
2335 num_events
, random_selector
);
2338 = (struct thread_info
*) find_inferior (&all_threads
,
2339 select_event_lwp_callback
,
2343 if (event_thread
!= NULL
)
2345 struct lwp_info
*event_lp
= get_thread_lwp (event_thread
);
2347 /* Switch the event LWP. */
2348 *orig_lp
= event_lp
;
2352 /* Decrement the suspend count of an LWP. */
2355 unsuspend_one_lwp (struct inferior_list_entry
*entry
, void *except
)
2357 struct thread_info
*thread
= (struct thread_info
*) entry
;
2358 struct lwp_info
*lwp
= get_thread_lwp (thread
);
2360 /* Ignore EXCEPT. */
2366 gdb_assert (lwp
->suspended
>= 0);
2370 /* Decrement the suspend count of all LWPs, except EXCEPT, if non
2374 unsuspend_all_lwps (struct lwp_info
*except
)
2376 find_inferior (&all_threads
, unsuspend_one_lwp
, except
);
2379 static void move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
);
2380 static int stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
,
2382 static int lwp_running (struct inferior_list_entry
*entry
, void *data
);
2383 static ptid_t
linux_wait_1 (ptid_t ptid
,
2384 struct target_waitstatus
*ourstatus
,
2385 int target_options
);
2387 /* Stabilize threads (move out of jump pads).
2389 If a thread is midway collecting a fast tracepoint, we need to
2390 finish the collection and move it out of the jump pad before
2391 reporting the signal.
2393 This avoids recursion while collecting (when a signal arrives
2394 midway, and the signal handler itself collects), which would trash
2395 the trace buffer. In case the user set a breakpoint in a signal
2396 handler, this avoids the backtrace showing the jump pad, etc..
2397 Most importantly, there are certain things we can't do safely if
2398 threads are stopped in a jump pad (or in its callee's). For
2401 - starting a new trace run. A thread still collecting the
2402 previous run, could trash the trace buffer when resumed. The trace
2403 buffer control structures would have been reset but the thread had
2404 no way to tell. The thread could even midway memcpy'ing to the
2405 buffer, which would mean that when resumed, it would clobber the
2406 trace buffer that had been set for a new run.
2408 - we can't rewrite/reuse the jump pads for new tracepoints
2409 safely. Say you do tstart while a thread is stopped midway while
2410 collecting. When the thread is later resumed, it finishes the
2411 collection, and returns to the jump pad, to execute the original
2412 instruction that was under the tracepoint jump at the time the
2413 older run had been started. If the jump pad had been rewritten
2414 since for something else in the new run, the thread would now
2415 execute the wrong / random instructions. */
2418 linux_stabilize_threads (void)
2420 struct thread_info
*saved_thread
;
2421 struct thread_info
*thread_stuck
;
2424 = (struct thread_info
*) find_inferior (&all_threads
,
2425 stuck_in_jump_pad_callback
,
2427 if (thread_stuck
!= NULL
)
2430 debug_printf ("can't stabilize, LWP %ld is stuck in jump pad\n",
2431 lwpid_of (thread_stuck
));
2435 saved_thread
= current_thread
;
2437 stabilizing_threads
= 1;
2440 for_each_inferior (&all_threads
, move_out_of_jump_pad_callback
);
2442 /* Loop until all are stopped out of the jump pads. */
2443 while (find_inferior (&all_threads
, lwp_running
, NULL
) != NULL
)
2445 struct target_waitstatus ourstatus
;
2446 struct lwp_info
*lwp
;
2449 /* Note that we go through the full wait even loop. While
2450 moving threads out of jump pad, we need to be able to step
2451 over internal breakpoints and such. */
2452 linux_wait_1 (minus_one_ptid
, &ourstatus
, 0);
2454 if (ourstatus
.kind
== TARGET_WAITKIND_STOPPED
)
2456 lwp
= get_thread_lwp (current_thread
);
2461 if (ourstatus
.value
.sig
!= GDB_SIGNAL_0
2462 || current_thread
->last_resume_kind
== resume_stop
)
2464 wstat
= W_STOPCODE (gdb_signal_to_host (ourstatus
.value
.sig
));
2465 enqueue_one_deferred_signal (lwp
, &wstat
);
2470 find_inferior (&all_threads
, unsuspend_one_lwp
, NULL
);
2472 stabilizing_threads
= 0;
2474 current_thread
= saved_thread
;
2479 = (struct thread_info
*) find_inferior (&all_threads
,
2480 stuck_in_jump_pad_callback
,
2482 if (thread_stuck
!= NULL
)
2483 debug_printf ("couldn't stabilize, LWP %ld got stuck in jump pad\n",
2484 lwpid_of (thread_stuck
));
2488 static void async_file_mark (void);
2490 /* Convenience function that is called when the kernel reports an
2491 event that is not passed out to GDB. */
2494 ignore_event (struct target_waitstatus
*ourstatus
)
2496 /* If we got an event, there may still be others, as a single
2497 SIGCHLD can indicate more than one child stopped. This forces
2498 another target_wait call. */
2501 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2505 /* Wait for process, returns status. */
2508 linux_wait_1 (ptid_t ptid
,
2509 struct target_waitstatus
*ourstatus
, int target_options
)
2512 struct lwp_info
*event_child
;
2515 int step_over_finished
;
2516 int bp_explains_trap
;
2517 int maybe_internal_trap
;
2525 debug_printf ("linux_wait_1: [%s]\n", target_pid_to_str (ptid
));
2528 /* Translate generic target options into linux options. */
2530 if (target_options
& TARGET_WNOHANG
)
2533 bp_explains_trap
= 0;
2536 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2538 if (ptid_equal (step_over_bkpt
, null_ptid
))
2539 pid
= linux_wait_for_event (ptid
, &w
, options
);
2543 debug_printf ("step_over_bkpt set [%s], doing a blocking wait\n",
2544 target_pid_to_str (step_over_bkpt
));
2545 pid
= linux_wait_for_event (step_over_bkpt
, &w
, options
& ~WNOHANG
);
2550 gdb_assert (target_options
& TARGET_WNOHANG
);
2554 debug_printf ("linux_wait_1 ret = null_ptid, "
2555 "TARGET_WAITKIND_IGNORE\n");
2559 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2566 debug_printf ("linux_wait_1 ret = null_ptid, "
2567 "TARGET_WAITKIND_NO_RESUMED\n");
2571 ourstatus
->kind
= TARGET_WAITKIND_NO_RESUMED
;
2575 event_child
= get_thread_lwp (current_thread
);
2577 /* linux_wait_for_event only returns an exit status for the last
2578 child of a process. Report it. */
2579 if (WIFEXITED (w
) || WIFSIGNALED (w
))
2583 ourstatus
->kind
= TARGET_WAITKIND_EXITED
;
2584 ourstatus
->value
.integer
= WEXITSTATUS (w
);
2588 debug_printf ("linux_wait_1 ret = %s, exited with "
2590 target_pid_to_str (ptid_of (current_thread
)),
2597 ourstatus
->kind
= TARGET_WAITKIND_SIGNALLED
;
2598 ourstatus
->value
.sig
= gdb_signal_from_host (WTERMSIG (w
));
2602 debug_printf ("linux_wait_1 ret = %s, terminated with "
2604 target_pid_to_str (ptid_of (current_thread
)),
2610 return ptid_of (current_thread
);
2613 /* If step-over executes a breakpoint instruction, it means a
2614 gdb/gdbserver breakpoint had been planted on top of a permanent
2615 breakpoint. The PC has been adjusted by
2616 check_stopped_by_breakpoint to point at the breakpoint address.
2617 Advance the PC manually past the breakpoint, otherwise the
2618 program would keep trapping the permanent breakpoint forever. */
2619 if (!ptid_equal (step_over_bkpt
, null_ptid
)
2620 && event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
)
2622 unsigned int increment_pc
= the_low_target
.breakpoint_len
;
2626 debug_printf ("step-over for %s executed software breakpoint\n",
2627 target_pid_to_str (ptid_of (current_thread
)));
2630 if (increment_pc
!= 0)
2632 struct regcache
*regcache
2633 = get_thread_regcache (current_thread
, 1);
2635 event_child
->stop_pc
+= increment_pc
;
2636 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
2638 if (!(*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))
2639 event_child
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
2643 /* If this event was not handled before, and is not a SIGTRAP, we
2644 report it. SIGILL and SIGSEGV are also treated as traps in case
2645 a breakpoint is inserted at the current PC. If this target does
2646 not support internal breakpoints at all, we also report the
2647 SIGTRAP without further processing; it's of no concern to us. */
2649 = (supports_breakpoints ()
2650 && (WSTOPSIG (w
) == SIGTRAP
2651 || ((WSTOPSIG (w
) == SIGILL
2652 || WSTOPSIG (w
) == SIGSEGV
)
2653 && (*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))));
2655 if (maybe_internal_trap
)
2657 /* Handle anything that requires bookkeeping before deciding to
2658 report the event or continue waiting. */
2660 /* First check if we can explain the SIGTRAP with an internal
2661 breakpoint, or if we should possibly report the event to GDB.
2662 Do this before anything that may remove or insert a
2664 bp_explains_trap
= breakpoint_inserted_here (event_child
->stop_pc
);
2666 /* We have a SIGTRAP, possibly a step-over dance has just
2667 finished. If so, tweak the state machine accordingly,
2668 reinsert breakpoints and delete any reinsert (software
2669 single-step) breakpoints. */
2670 step_over_finished
= finish_step_over (event_child
);
2672 /* Now invoke the callbacks of any internal breakpoints there. */
2673 check_breakpoints (event_child
->stop_pc
);
2675 /* Handle tracepoint data collecting. This may overflow the
2676 trace buffer, and cause a tracing stop, removing
2678 trace_event
= handle_tracepoints (event_child
);
2680 if (bp_explains_trap
)
2682 /* If we stepped or ran into an internal breakpoint, we've
2683 already handled it. So next time we resume (from this
2684 PC), we should step over it. */
2686 debug_printf ("Hit a gdbserver breakpoint.\n");
2688 if (breakpoint_here (event_child
->stop_pc
))
2689 event_child
->need_step_over
= 1;
2694 /* We have some other signal, possibly a step-over dance was in
2695 progress, and it should be cancelled too. */
2696 step_over_finished
= finish_step_over (event_child
);
2699 /* We have all the data we need. Either report the event to GDB, or
2700 resume threads and keep waiting for more. */
2702 /* If we're collecting a fast tracepoint, finish the collection and
2703 move out of the jump pad before delivering a signal. See
2704 linux_stabilize_threads. */
2707 && WSTOPSIG (w
) != SIGTRAP
2708 && supports_fast_tracepoints ()
2709 && agent_loaded_p ())
2712 debug_printf ("Got signal %d for LWP %ld. Check if we need "
2713 "to defer or adjust it.\n",
2714 WSTOPSIG (w
), lwpid_of (current_thread
));
2716 /* Allow debugging the jump pad itself. */
2717 if (current_thread
->last_resume_kind
!= resume_step
2718 && maybe_move_out_of_jump_pad (event_child
, &w
))
2720 enqueue_one_deferred_signal (event_child
, &w
);
2723 debug_printf ("Signal %d for LWP %ld deferred (in jump pad)\n",
2724 WSTOPSIG (w
), lwpid_of (current_thread
));
2726 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
2728 return ignore_event (ourstatus
);
2732 if (event_child
->collecting_fast_tracepoint
)
2735 debug_printf ("LWP %ld was trying to move out of the jump pad (%d). "
2736 "Check if we're already there.\n",
2737 lwpid_of (current_thread
),
2738 event_child
->collecting_fast_tracepoint
);
2742 event_child
->collecting_fast_tracepoint
2743 = linux_fast_tracepoint_collecting (event_child
, NULL
);
2745 if (event_child
->collecting_fast_tracepoint
!= 1)
2747 /* No longer need this breakpoint. */
2748 if (event_child
->exit_jump_pad_bkpt
!= NULL
)
2751 debug_printf ("No longer need exit-jump-pad bkpt; removing it."
2752 "stopping all threads momentarily.\n");
2754 /* Other running threads could hit this breakpoint.
2755 We don't handle moribund locations like GDB does,
2756 instead we always pause all threads when removing
2757 breakpoints, so that any step-over or
2758 decr_pc_after_break adjustment is always taken
2759 care of while the breakpoint is still
2761 stop_all_lwps (1, event_child
);
2763 delete_breakpoint (event_child
->exit_jump_pad_bkpt
);
2764 event_child
->exit_jump_pad_bkpt
= NULL
;
2766 unstop_all_lwps (1, event_child
);
2768 gdb_assert (event_child
->suspended
>= 0);
2772 if (event_child
->collecting_fast_tracepoint
== 0)
2775 debug_printf ("fast tracepoint finished "
2776 "collecting successfully.\n");
2778 /* We may have a deferred signal to report. */
2779 if (dequeue_one_deferred_signal (event_child
, &w
))
2782 debug_printf ("dequeued one signal.\n");
2787 debug_printf ("no deferred signals.\n");
2789 if (stabilizing_threads
)
2791 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
2792 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
2796 debug_printf ("linux_wait_1 ret = %s, stopped "
2797 "while stabilizing threads\n",
2798 target_pid_to_str (ptid_of (current_thread
)));
2802 return ptid_of (current_thread
);
2808 /* Check whether GDB would be interested in this event. */
2810 /* If GDB is not interested in this signal, don't stop other
2811 threads, and don't report it to GDB. Just resume the inferior
2812 right away. We do this for threading-related signals as well as
2813 any that GDB specifically requested we ignore. But never ignore
2814 SIGSTOP if we sent it ourselves, and do not ignore signals when
2815 stepping - they may require special handling to skip the signal
2816 handler. Also never ignore signals that could be caused by a
2818 /* FIXME drow/2002-06-09: Get signal numbers from the inferior's
2821 && current_thread
->last_resume_kind
!= resume_step
2823 #if defined (USE_THREAD_DB) && !defined (__ANDROID__)
2824 (current_process ()->priv
->thread_db
!= NULL
2825 && (WSTOPSIG (w
) == __SIGRTMIN
2826 || WSTOPSIG (w
) == __SIGRTMIN
+ 1))
2829 (pass_signals
[gdb_signal_from_host (WSTOPSIG (w
))]
2830 && !(WSTOPSIG (w
) == SIGSTOP
2831 && current_thread
->last_resume_kind
== resume_stop
)
2832 && !linux_wstatus_maybe_breakpoint (w
))))
2834 siginfo_t info
, *info_p
;
2837 debug_printf ("Ignored signal %d for LWP %ld.\n",
2838 WSTOPSIG (w
), lwpid_of (current_thread
));
2840 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
2841 (PTRACE_TYPE_ARG3
) 0, &info
) == 0)
2845 linux_resume_one_lwp (event_child
, event_child
->stepping
,
2846 WSTOPSIG (w
), info_p
);
2847 return ignore_event (ourstatus
);
2850 /* Note that all addresses are always "out of the step range" when
2851 there's no range to begin with. */
2852 in_step_range
= lwp_in_step_range (event_child
);
2854 /* If GDB wanted this thread to single step, and the thread is out
2855 of the step range, we always want to report the SIGTRAP, and let
2856 GDB handle it. Watchpoints should always be reported. So should
2857 signals we can't explain. A SIGTRAP we can't explain could be a
2858 GDB breakpoint --- we may or not support Z0 breakpoints. If we
2859 do, we're be able to handle GDB breakpoints on top of internal
2860 breakpoints, by handling the internal breakpoint and still
2861 reporting the event to GDB. If we don't, we're out of luck, GDB
2862 won't see the breakpoint hit. */
2863 report_to_gdb
= (!maybe_internal_trap
2864 || (current_thread
->last_resume_kind
== resume_step
2866 || event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
2867 || (!step_over_finished
&& !in_step_range
2868 && !bp_explains_trap
&& !trace_event
)
2869 || (gdb_breakpoint_here (event_child
->stop_pc
)
2870 && gdb_condition_true_at_breakpoint (event_child
->stop_pc
)
2871 && gdb_no_commands_at_breakpoint (event_child
->stop_pc
)));
2873 run_breakpoint_commands (event_child
->stop_pc
);
2875 /* We found no reason GDB would want us to stop. We either hit one
2876 of our own breakpoints, or finished an internal step GDB
2877 shouldn't know about. */
2882 if (bp_explains_trap
)
2883 debug_printf ("Hit a gdbserver breakpoint.\n");
2884 if (step_over_finished
)
2885 debug_printf ("Step-over finished.\n");
2887 debug_printf ("Tracepoint event.\n");
2888 if (lwp_in_step_range (event_child
))
2889 debug_printf ("Range stepping pc 0x%s [0x%s, 0x%s).\n",
2890 paddress (event_child
->stop_pc
),
2891 paddress (event_child
->step_range_start
),
2892 paddress (event_child
->step_range_end
));
2895 /* We're not reporting this breakpoint to GDB, so apply the
2896 decr_pc_after_break adjustment to the inferior's regcache
2899 if (the_low_target
.set_pc
!= NULL
)
2901 struct regcache
*regcache
2902 = get_thread_regcache (current_thread
, 1);
2903 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
2906 /* We may have finished stepping over a breakpoint. If so,
2907 we've stopped and suspended all LWPs momentarily except the
2908 stepping one. This is where we resume them all again. We're
2909 going to keep waiting, so use proceed, which handles stepping
2910 over the next breakpoint. */
2912 debug_printf ("proceeding all threads.\n");
2914 if (step_over_finished
)
2915 unsuspend_all_lwps (event_child
);
2917 proceed_all_lwps ();
2918 return ignore_event (ourstatus
);
2923 if (current_thread
->last_resume_kind
== resume_step
)
2925 if (event_child
->step_range_start
== event_child
->step_range_end
)
2926 debug_printf ("GDB wanted to single-step, reporting event.\n");
2927 else if (!lwp_in_step_range (event_child
))
2928 debug_printf ("Out of step range, reporting event.\n");
2930 if (event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
)
2931 debug_printf ("Stopped by watchpoint.\n");
2932 else if (gdb_breakpoint_here (event_child
->stop_pc
))
2933 debug_printf ("Stopped by GDB breakpoint.\n");
2935 debug_printf ("Hit a non-gdbserver trap event.\n");
2938 /* Alright, we're going to report a stop. */
2940 if (!stabilizing_threads
)
2942 /* In all-stop, stop all threads. */
2944 stop_all_lwps (0, NULL
);
2946 /* If we're not waiting for a specific LWP, choose an event LWP
2947 from among those that have had events. Giving equal priority
2948 to all LWPs that have had events helps prevent
2950 if (ptid_equal (ptid
, minus_one_ptid
))
2952 event_child
->status_pending_p
= 1;
2953 event_child
->status_pending
= w
;
2955 select_event_lwp (&event_child
);
2957 /* current_thread and event_child must stay in sync. */
2958 current_thread
= get_lwp_thread (event_child
);
2960 event_child
->status_pending_p
= 0;
2961 w
= event_child
->status_pending
;
2964 if (step_over_finished
)
2968 /* If we were doing a step-over, all other threads but
2969 the stepping one had been paused in start_step_over,
2970 with their suspend counts incremented. We don't want
2971 to do a full unstop/unpause, because we're in
2972 all-stop mode (so we want threads stopped), but we
2973 still need to unsuspend the other threads, to
2974 decrement their `suspended' count back. */
2975 unsuspend_all_lwps (event_child
);
2979 /* If we just finished a step-over, then all threads had
2980 been momentarily paused. In all-stop, that's fine,
2981 we want threads stopped by now anyway. In non-stop,
2982 we need to re-resume threads that GDB wanted to be
2984 unstop_all_lwps (1, event_child
);
2988 /* Stabilize threads (move out of jump pads). */
2990 stabilize_threads ();
2994 /* If we just finished a step-over, then all threads had been
2995 momentarily paused. In all-stop, that's fine, we want
2996 threads stopped by now anyway. In non-stop, we need to
2997 re-resume threads that GDB wanted to be running. */
2998 if (step_over_finished
)
2999 unstop_all_lwps (1, event_child
);
3002 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
3004 /* Now that we've selected our final event LWP, un-adjust its PC if
3005 it was a software breakpoint, and the client doesn't know we can
3006 adjust the breakpoint ourselves. */
3007 if (event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3008 && !swbreak_feature
)
3010 int decr_pc
= the_low_target
.decr_pc_after_break
;
3014 struct regcache
*regcache
3015 = get_thread_regcache (current_thread
, 1);
3016 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
+ decr_pc
);
3020 if (current_thread
->last_resume_kind
== resume_stop
3021 && WSTOPSIG (w
) == SIGSTOP
)
3023 /* A thread that has been requested to stop by GDB with vCont;t,
3024 and it stopped cleanly, so report as SIG0. The use of
3025 SIGSTOP is an implementation detail. */
3026 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
3028 else if (current_thread
->last_resume_kind
== resume_stop
3029 && WSTOPSIG (w
) != SIGSTOP
)
3031 /* A thread that has been requested to stop by GDB with vCont;t,
3032 but, it stopped for other reasons. */
3033 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
3037 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
3040 gdb_assert (ptid_equal (step_over_bkpt
, null_ptid
));
3044 debug_printf ("linux_wait_1 ret = %s, %d, %d\n",
3045 target_pid_to_str (ptid_of (current_thread
)),
3046 ourstatus
->kind
, ourstatus
->value
.sig
);
3050 return ptid_of (current_thread
);
3053 /* Get rid of any pending event in the pipe. */
3055 async_file_flush (void)
3061 ret
= read (linux_event_pipe
[0], &buf
, 1);
3062 while (ret
>= 0 || (ret
== -1 && errno
== EINTR
));
3065 /* Put something in the pipe, so the event loop wakes up. */
3067 async_file_mark (void)
3071 async_file_flush ();
3074 ret
= write (linux_event_pipe
[1], "+", 1);
3075 while (ret
== 0 || (ret
== -1 && errno
== EINTR
));
3077 /* Ignore EAGAIN. If the pipe is full, the event loop will already
3078 be awakened anyway. */
3082 linux_wait (ptid_t ptid
,
3083 struct target_waitstatus
*ourstatus
, int target_options
)
3087 /* Flush the async file first. */
3088 if (target_is_async_p ())
3089 async_file_flush ();
3093 event_ptid
= linux_wait_1 (ptid
, ourstatus
, target_options
);
3095 while ((target_options
& TARGET_WNOHANG
) == 0
3096 && ptid_equal (event_ptid
, null_ptid
)
3097 && ourstatus
->kind
== TARGET_WAITKIND_IGNORE
);
3099 /* If at least one stop was reported, there may be more. A single
3100 SIGCHLD can signal more than one child stop. */
3101 if (target_is_async_p ()
3102 && (target_options
& TARGET_WNOHANG
) != 0
3103 && !ptid_equal (event_ptid
, null_ptid
))
3109 /* Send a signal to an LWP. */
3112 kill_lwp (unsigned long lwpid
, int signo
)
3114 /* Use tkill, if possible, in case we are using nptl threads. If tkill
3115 fails, then we are not using nptl threads and we should be using kill. */
3119 static int tkill_failed
;
3126 ret
= syscall (__NR_tkill
, lwpid
, signo
);
3127 if (errno
!= ENOSYS
)
3134 return kill (lwpid
, signo
);
3138 linux_stop_lwp (struct lwp_info
*lwp
)
3144 send_sigstop (struct lwp_info
*lwp
)
3148 pid
= lwpid_of (get_lwp_thread (lwp
));
3150 /* If we already have a pending stop signal for this process, don't
3152 if (lwp
->stop_expected
)
3155 debug_printf ("Have pending sigstop for lwp %d\n", pid
);
3161 debug_printf ("Sending sigstop to lwp %d\n", pid
);
3163 lwp
->stop_expected
= 1;
3164 kill_lwp (pid
, SIGSTOP
);
3168 send_sigstop_callback (struct inferior_list_entry
*entry
, void *except
)
3170 struct thread_info
*thread
= (struct thread_info
*) entry
;
3171 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3173 /* Ignore EXCEPT. */
3184 /* Increment the suspend count of an LWP, and stop it, if not stopped
3187 suspend_and_send_sigstop_callback (struct inferior_list_entry
*entry
,
3190 struct thread_info
*thread
= (struct thread_info
*) entry
;
3191 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3193 /* Ignore EXCEPT. */
3199 return send_sigstop_callback (entry
, except
);
3203 mark_lwp_dead (struct lwp_info
*lwp
, int wstat
)
3205 /* It's dead, really. */
3208 /* Store the exit status for later. */
3209 lwp
->status_pending_p
= 1;
3210 lwp
->status_pending
= wstat
;
3212 /* Prevent trying to stop it. */
3215 /* No further stops are expected from a dead lwp. */
3216 lwp
->stop_expected
= 0;
3219 /* Wait for all children to stop for the SIGSTOPs we just queued. */
3222 wait_for_sigstop (void)
3224 struct thread_info
*saved_thread
;
3229 saved_thread
= current_thread
;
3230 if (saved_thread
!= NULL
)
3231 saved_tid
= saved_thread
->entry
.id
;
3233 saved_tid
= null_ptid
; /* avoid bogus unused warning */
3236 debug_printf ("wait_for_sigstop: pulling events\n");
3238 /* Passing NULL_PTID as filter indicates we want all events to be
3239 left pending. Eventually this returns when there are no
3240 unwaited-for children left. */
3241 ret
= linux_wait_for_event_filtered (minus_one_ptid
, null_ptid
,
3243 gdb_assert (ret
== -1);
3245 if (saved_thread
== NULL
|| linux_thread_alive (saved_tid
))
3246 current_thread
= saved_thread
;
3250 debug_printf ("Previously current thread died.\n");
3254 /* We can't change the current inferior behind GDB's back,
3255 otherwise, a subsequent command may apply to the wrong
3257 current_thread
= NULL
;
3261 /* Set a valid thread as current. */
3262 set_desired_thread (0);
3267 /* Returns true if LWP ENTRY is stopped in a jump pad, and we can't
3268 move it out, because we need to report the stop event to GDB. For
3269 example, if the user puts a breakpoint in the jump pad, it's
3270 because she wants to debug it. */
3273 stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
, void *data
)
3275 struct thread_info
*thread
= (struct thread_info
*) entry
;
3276 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3278 gdb_assert (lwp
->suspended
== 0);
3279 gdb_assert (lwp
->stopped
);
3281 /* Allow debugging the jump pad, gdb_collect, etc.. */
3282 return (supports_fast_tracepoints ()
3283 && agent_loaded_p ()
3284 && (gdb_breakpoint_here (lwp
->stop_pc
)
3285 || lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
3286 || thread
->last_resume_kind
== resume_step
)
3287 && linux_fast_tracepoint_collecting (lwp
, NULL
));
3291 move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
)
3293 struct thread_info
*thread
= (struct thread_info
*) entry
;
3294 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3297 gdb_assert (lwp
->suspended
== 0);
3298 gdb_assert (lwp
->stopped
);
3300 wstat
= lwp
->status_pending_p
? &lwp
->status_pending
: NULL
;
3302 /* Allow debugging the jump pad, gdb_collect, etc. */
3303 if (!gdb_breakpoint_here (lwp
->stop_pc
)
3304 && lwp
->stop_reason
!= TARGET_STOPPED_BY_WATCHPOINT
3305 && thread
->last_resume_kind
!= resume_step
3306 && maybe_move_out_of_jump_pad (lwp
, wstat
))
3309 debug_printf ("LWP %ld needs stabilizing (in jump pad)\n",
3314 lwp
->status_pending_p
= 0;
3315 enqueue_one_deferred_signal (lwp
, wstat
);
3318 debug_printf ("Signal %d for LWP %ld deferred "
3320 WSTOPSIG (*wstat
), lwpid_of (thread
));
3323 linux_resume_one_lwp (lwp
, 0, 0, NULL
);
3330 lwp_running (struct inferior_list_entry
*entry
, void *data
)
3332 struct thread_info
*thread
= (struct thread_info
*) entry
;
3333 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3342 /* Stop all lwps that aren't stopped yet, except EXCEPT, if not NULL.
3343 If SUSPEND, then also increase the suspend count of every LWP,
3347 stop_all_lwps (int suspend
, struct lwp_info
*except
)
3349 /* Should not be called recursively. */
3350 gdb_assert (stopping_threads
== NOT_STOPPING_THREADS
);
3355 debug_printf ("stop_all_lwps (%s, except=%s)\n",
3356 suspend
? "stop-and-suspend" : "stop",
3358 ? target_pid_to_str (ptid_of (get_lwp_thread (except
)))
3362 stopping_threads
= (suspend
3363 ? STOPPING_AND_SUSPENDING_THREADS
3364 : STOPPING_THREADS
);
3367 find_inferior (&all_threads
, suspend_and_send_sigstop_callback
, except
);
3369 find_inferior (&all_threads
, send_sigstop_callback
, except
);
3370 wait_for_sigstop ();
3371 stopping_threads
= NOT_STOPPING_THREADS
;
3375 debug_printf ("stop_all_lwps done, setting stopping_threads "
3376 "back to !stopping\n");
3381 /* Resume execution of the inferior process.
3382 If STEP is nonzero, single-step it.
3383 If SIGNAL is nonzero, give it that signal. */
3386 linux_resume_one_lwp (struct lwp_info
*lwp
,
3387 int step
, int signal
, siginfo_t
*info
)
3389 struct thread_info
*thread
= get_lwp_thread (lwp
);
3390 struct thread_info
*saved_thread
;
3391 int fast_tp_collecting
;
3393 if (lwp
->stopped
== 0)
3396 fast_tp_collecting
= lwp
->collecting_fast_tracepoint
;
3398 gdb_assert (!stabilizing_threads
|| fast_tp_collecting
);
3400 /* Cancel actions that rely on GDB not changing the PC (e.g., the
3401 user used the "jump" command, or "set $pc = foo"). */
3402 if (lwp
->stop_pc
!= get_pc (lwp
))
3404 /* Collecting 'while-stepping' actions doesn't make sense
3406 release_while_stepping_state_list (thread
);
3409 /* If we have pending signals or status, and a new signal, enqueue the
3410 signal. Also enqueue the signal if we are waiting to reinsert a
3411 breakpoint; it will be picked up again below. */
3413 && (lwp
->status_pending_p
3414 || lwp
->pending_signals
!= NULL
3415 || lwp
->bp_reinsert
!= 0
3416 || fast_tp_collecting
))
3418 struct pending_signals
*p_sig
;
3419 p_sig
= xmalloc (sizeof (*p_sig
));
3420 p_sig
->prev
= lwp
->pending_signals
;
3421 p_sig
->signal
= signal
;
3423 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
3425 memcpy (&p_sig
->info
, info
, sizeof (siginfo_t
));
3426 lwp
->pending_signals
= p_sig
;
3429 if (lwp
->status_pending_p
)
3432 debug_printf ("Not resuming lwp %ld (%s, signal %d, stop %s);"
3433 " has pending status\n",
3434 lwpid_of (thread
), step
? "step" : "continue", signal
,
3435 lwp
->stop_expected
? "expected" : "not expected");
3439 saved_thread
= current_thread
;
3440 current_thread
= thread
;
3443 debug_printf ("Resuming lwp %ld (%s, signal %d, stop %s)\n",
3444 lwpid_of (thread
), step
? "step" : "continue", signal
,
3445 lwp
->stop_expected
? "expected" : "not expected");
3447 /* This bit needs some thinking about. If we get a signal that
3448 we must report while a single-step reinsert is still pending,
3449 we often end up resuming the thread. It might be better to
3450 (ew) allow a stack of pending events; then we could be sure that
3451 the reinsert happened right away and not lose any signals.
3453 Making this stack would also shrink the window in which breakpoints are
3454 uninserted (see comment in linux_wait_for_lwp) but not enough for
3455 complete correctness, so it won't solve that problem. It may be
3456 worthwhile just to solve this one, however. */
3457 if (lwp
->bp_reinsert
!= 0)
3460 debug_printf (" pending reinsert at 0x%s\n",
3461 paddress (lwp
->bp_reinsert
));
3463 if (can_hardware_single_step ())
3465 if (fast_tp_collecting
== 0)
3468 fprintf (stderr
, "BAD - reinserting but not stepping.\n");
3470 fprintf (stderr
, "BAD - reinserting and suspended(%d).\n",
3477 /* Postpone any pending signal. It was enqueued above. */
3481 if (fast_tp_collecting
== 1)
3484 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
3485 " (exit-jump-pad-bkpt)\n",
3488 /* Postpone any pending signal. It was enqueued above. */
3491 else if (fast_tp_collecting
== 2)
3494 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
3495 " single-stepping\n",
3498 if (can_hardware_single_step ())
3502 internal_error (__FILE__
, __LINE__
,
3503 "moving out of jump pad single-stepping"
3504 " not implemented on this target");
3507 /* Postpone any pending signal. It was enqueued above. */
3511 /* If we have while-stepping actions in this thread set it stepping.
3512 If we have a signal to deliver, it may or may not be set to
3513 SIG_IGN, we don't know. Assume so, and allow collecting
3514 while-stepping into a signal handler. A possible smart thing to
3515 do would be to set an internal breakpoint at the signal return
3516 address, continue, and carry on catching this while-stepping
3517 action only when that breakpoint is hit. A future
3519 if (thread
->while_stepping
!= NULL
3520 && can_hardware_single_step ())
3523 debug_printf ("lwp %ld has a while-stepping action -> forcing step.\n",
3528 if (the_low_target
.get_pc
!= NULL
)
3530 struct regcache
*regcache
= get_thread_regcache (current_thread
, 1);
3532 lwp
->stop_pc
= (*the_low_target
.get_pc
) (regcache
);
3536 debug_printf (" %s from pc 0x%lx\n", step
? "step" : "continue",
3537 (long) lwp
->stop_pc
);
3541 /* If we have pending signals, consume one unless we are trying to
3542 reinsert a breakpoint or we're trying to finish a fast tracepoint
3544 if (lwp
->pending_signals
!= NULL
3545 && lwp
->bp_reinsert
== 0
3546 && fast_tp_collecting
== 0)
3548 struct pending_signals
**p_sig
;
3550 p_sig
= &lwp
->pending_signals
;
3551 while ((*p_sig
)->prev
!= NULL
)
3552 p_sig
= &(*p_sig
)->prev
;
3554 signal
= (*p_sig
)->signal
;
3555 if ((*p_sig
)->info
.si_signo
!= 0)
3556 ptrace (PTRACE_SETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
3563 if (the_low_target
.prepare_to_resume
!= NULL
)
3564 the_low_target
.prepare_to_resume (lwp
);
3566 regcache_invalidate_thread (thread
);
3569 lwp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3570 lwp
->stepping
= step
;
3571 ptrace (step
? PTRACE_SINGLESTEP
: PTRACE_CONT
, lwpid_of (thread
),
3572 (PTRACE_TYPE_ARG3
) 0,
3573 /* Coerce to a uintptr_t first to avoid potential gcc warning
3574 of coercing an 8 byte integer to a 4 byte pointer. */
3575 (PTRACE_TYPE_ARG4
) (uintptr_t) signal
);
3577 current_thread
= saved_thread
;
3580 /* ESRCH from ptrace either means that the thread was already
3581 running (an error) or that it is gone (a race condition). If
3582 it's gone, we will get a notification the next time we wait,
3583 so we can ignore the error. We could differentiate these
3584 two, but it's tricky without waiting; the thread still exists
3585 as a zombie, so sending it signal 0 would succeed. So just
3590 perror_with_name ("ptrace");
3594 struct thread_resume_array
3596 struct thread_resume
*resume
;
3600 /* This function is called once per thread via find_inferior.
3601 ARG is a pointer to a thread_resume_array struct.
3602 We look up the thread specified by ENTRY in ARG, and mark the thread
3603 with a pointer to the appropriate resume request.
3605 This algorithm is O(threads * resume elements), but resume elements
3606 is small (and will remain small at least until GDB supports thread
3610 linux_set_resume_request (struct inferior_list_entry
*entry
, void *arg
)
3612 struct thread_info
*thread
= (struct thread_info
*) entry
;
3613 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3615 struct thread_resume_array
*r
;
3619 for (ndx
= 0; ndx
< r
->n
; ndx
++)
3621 ptid_t ptid
= r
->resume
[ndx
].thread
;
3622 if (ptid_equal (ptid
, minus_one_ptid
)
3623 || ptid_equal (ptid
, entry
->id
)
3624 /* Handle both 'pPID' and 'pPID.-1' as meaning 'all threads
3626 || (ptid_get_pid (ptid
) == pid_of (thread
)
3627 && (ptid_is_pid (ptid
)
3628 || ptid_get_lwp (ptid
) == -1)))
3630 if (r
->resume
[ndx
].kind
== resume_stop
3631 && thread
->last_resume_kind
== resume_stop
)
3634 debug_printf ("already %s LWP %ld at GDB's request\n",
3635 (thread
->last_status
.kind
3636 == TARGET_WAITKIND_STOPPED
)
3644 lwp
->resume
= &r
->resume
[ndx
];
3645 thread
->last_resume_kind
= lwp
->resume
->kind
;
3647 lwp
->step_range_start
= lwp
->resume
->step_range_start
;
3648 lwp
->step_range_end
= lwp
->resume
->step_range_end
;
3650 /* If we had a deferred signal to report, dequeue one now.
3651 This can happen if LWP gets more than one signal while
3652 trying to get out of a jump pad. */
3654 && !lwp
->status_pending_p
3655 && dequeue_one_deferred_signal (lwp
, &lwp
->status_pending
))
3657 lwp
->status_pending_p
= 1;
3660 debug_printf ("Dequeueing deferred signal %d for LWP %ld, "
3661 "leaving status pending.\n",
3662 WSTOPSIG (lwp
->status_pending
),
3670 /* No resume action for this thread. */
3676 /* find_inferior callback for linux_resume.
3677 Set *FLAG_P if this lwp has an interesting status pending. */
3680 resume_status_pending_p (struct inferior_list_entry
*entry
, void *flag_p
)
3682 struct thread_info
*thread
= (struct thread_info
*) entry
;
3683 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3685 /* LWPs which will not be resumed are not interesting, because
3686 we might not wait for them next time through linux_wait. */
3687 if (lwp
->resume
== NULL
)
3690 if (thread_still_has_status_pending_p (thread
))
3691 * (int *) flag_p
= 1;
3696 /* Return 1 if this lwp that GDB wants running is stopped at an
3697 internal breakpoint that we need to step over. It assumes that any
3698 required STOP_PC adjustment has already been propagated to the
3699 inferior's regcache. */
3702 need_step_over_p (struct inferior_list_entry
*entry
, void *dummy
)
3704 struct thread_info
*thread
= (struct thread_info
*) entry
;
3705 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3706 struct thread_info
*saved_thread
;
3709 /* LWPs which will not be resumed are not interesting, because we
3710 might not wait for them next time through linux_wait. */
3715 debug_printf ("Need step over [LWP %ld]? Ignoring, not stopped\n",
3720 if (thread
->last_resume_kind
== resume_stop
)
3723 debug_printf ("Need step over [LWP %ld]? Ignoring, should remain"
3729 gdb_assert (lwp
->suspended
>= 0);
3734 debug_printf ("Need step over [LWP %ld]? Ignoring, suspended\n",
3739 if (!lwp
->need_step_over
)
3742 debug_printf ("Need step over [LWP %ld]? No\n", lwpid_of (thread
));
3745 if (lwp
->status_pending_p
)
3748 debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
3754 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
3758 /* If the PC has changed since we stopped, then don't do anything,
3759 and let the breakpoint/tracepoint be hit. This happens if, for
3760 instance, GDB handled the decr_pc_after_break subtraction itself,
3761 GDB is OOL stepping this thread, or the user has issued a "jump"
3762 command, or poked thread's registers herself. */
3763 if (pc
!= lwp
->stop_pc
)
3766 debug_printf ("Need step over [LWP %ld]? Cancelling, PC was changed. "
3767 "Old stop_pc was 0x%s, PC is now 0x%s\n",
3769 paddress (lwp
->stop_pc
), paddress (pc
));
3771 lwp
->need_step_over
= 0;
3775 saved_thread
= current_thread
;
3776 current_thread
= thread
;
3778 /* We can only step over breakpoints we know about. */
3779 if (breakpoint_here (pc
) || fast_tracepoint_jump_here (pc
))
3781 /* Don't step over a breakpoint that GDB expects to hit
3782 though. If the condition is being evaluated on the target's side
3783 and it evaluate to false, step over this breakpoint as well. */
3784 if (gdb_breakpoint_here (pc
)
3785 && gdb_condition_true_at_breakpoint (pc
)
3786 && gdb_no_commands_at_breakpoint (pc
))
3789 debug_printf ("Need step over [LWP %ld]? yes, but found"
3790 " GDB breakpoint at 0x%s; skipping step over\n",
3791 lwpid_of (thread
), paddress (pc
));
3793 current_thread
= saved_thread
;
3799 debug_printf ("Need step over [LWP %ld]? yes, "
3800 "found breakpoint at 0x%s\n",
3801 lwpid_of (thread
), paddress (pc
));
3803 /* We've found an lwp that needs stepping over --- return 1 so
3804 that find_inferior stops looking. */
3805 current_thread
= saved_thread
;
3807 /* If the step over is cancelled, this is set again. */
3808 lwp
->need_step_over
= 0;
3813 current_thread
= saved_thread
;
3816 debug_printf ("Need step over [LWP %ld]? No, no breakpoint found"
3818 lwpid_of (thread
), paddress (pc
));
3823 /* Start a step-over operation on LWP. When LWP stopped at a
3824 breakpoint, to make progress, we need to remove the breakpoint out
3825 of the way. If we let other threads run while we do that, they may
3826 pass by the breakpoint location and miss hitting it. To avoid
3827 that, a step-over momentarily stops all threads while LWP is
3828 single-stepped while the breakpoint is temporarily uninserted from
3829 the inferior. When the single-step finishes, we reinsert the
3830 breakpoint, and let all threads that are supposed to be running,
3833 On targets that don't support hardware single-step, we don't
3834 currently support full software single-stepping. Instead, we only
3835 support stepping over the thread event breakpoint, by asking the
3836 low target where to place a reinsert breakpoint. Since this
3837 routine assumes the breakpoint being stepped over is a thread event
3838 breakpoint, it usually assumes the return address of the current
3839 function is a good enough place to set the reinsert breakpoint. */
3842 start_step_over (struct lwp_info
*lwp
)
3844 struct thread_info
*thread
= get_lwp_thread (lwp
);
3845 struct thread_info
*saved_thread
;
3850 debug_printf ("Starting step-over on LWP %ld. Stopping all threads\n",
3853 stop_all_lwps (1, lwp
);
3854 gdb_assert (lwp
->suspended
== 0);
3857 debug_printf ("Done stopping all threads for step-over.\n");
3859 /* Note, we should always reach here with an already adjusted PC,
3860 either by GDB (if we're resuming due to GDB's request), or by our
3861 caller, if we just finished handling an internal breakpoint GDB
3862 shouldn't care about. */
3865 saved_thread
= current_thread
;
3866 current_thread
= thread
;
3868 lwp
->bp_reinsert
= pc
;
3869 uninsert_breakpoints_at (pc
);
3870 uninsert_fast_tracepoint_jumps_at (pc
);
3872 if (can_hardware_single_step ())
3878 CORE_ADDR raddr
= (*the_low_target
.breakpoint_reinsert_addr
) ();
3879 set_reinsert_breakpoint (raddr
);
3883 current_thread
= saved_thread
;
3885 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
3887 /* Require next event from this LWP. */
3888 step_over_bkpt
= thread
->entry
.id
;
3892 /* Finish a step-over. Reinsert the breakpoint we had uninserted in
3893 start_step_over, if still there, and delete any reinsert
3894 breakpoints we've set, on non hardware single-step targets. */
3897 finish_step_over (struct lwp_info
*lwp
)
3899 if (lwp
->bp_reinsert
!= 0)
3902 debug_printf ("Finished step over.\n");
3904 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
3905 may be no breakpoint to reinsert there by now. */
3906 reinsert_breakpoints_at (lwp
->bp_reinsert
);
3907 reinsert_fast_tracepoint_jumps_at (lwp
->bp_reinsert
);
3909 lwp
->bp_reinsert
= 0;
3911 /* Delete any software-single-step reinsert breakpoints. No
3912 longer needed. We don't have to worry about other threads
3913 hitting this trap, and later not being able to explain it,
3914 because we were stepping over a breakpoint, and we hold all
3915 threads but LWP stopped while doing that. */
3916 if (!can_hardware_single_step ())
3917 delete_reinsert_breakpoints ();
3919 step_over_bkpt
= null_ptid
;
3926 /* This function is called once per thread. We check the thread's resume
3927 request, which will tell us whether to resume, step, or leave the thread
3928 stopped; and what signal, if any, it should be sent.
3930 For threads which we aren't explicitly told otherwise, we preserve
3931 the stepping flag; this is used for stepping over gdbserver-placed
3934 If pending_flags was set in any thread, we queue any needed
3935 signals, since we won't actually resume. We already have a pending
3936 event to report, so we don't need to preserve any step requests;
3937 they should be re-issued if necessary. */
3940 linux_resume_one_thread (struct inferior_list_entry
*entry
, void *arg
)
3942 struct thread_info
*thread
= (struct thread_info
*) entry
;
3943 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3945 int leave_all_stopped
= * (int *) arg
;
3948 if (lwp
->resume
== NULL
)
3951 if (lwp
->resume
->kind
== resume_stop
)
3954 debug_printf ("resume_stop request for LWP %ld\n", lwpid_of (thread
));
3959 debug_printf ("stopping LWP %ld\n", lwpid_of (thread
));
3961 /* Stop the thread, and wait for the event asynchronously,
3962 through the event loop. */
3968 debug_printf ("already stopped LWP %ld\n",
3971 /* The LWP may have been stopped in an internal event that
3972 was not meant to be notified back to GDB (e.g., gdbserver
3973 breakpoint), so we should be reporting a stop event in
3976 /* If the thread already has a pending SIGSTOP, this is a
3977 no-op. Otherwise, something later will presumably resume
3978 the thread and this will cause it to cancel any pending
3979 operation, due to last_resume_kind == resume_stop. If
3980 the thread already has a pending status to report, we
3981 will still report it the next time we wait - see
3982 status_pending_p_callback. */
3984 /* If we already have a pending signal to report, then
3985 there's no need to queue a SIGSTOP, as this means we're
3986 midway through moving the LWP out of the jumppad, and we
3987 will report the pending signal as soon as that is
3989 if (lwp
->pending_signals_to_report
== NULL
)
3993 /* For stop requests, we're done. */
3995 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
3999 /* If this thread which is about to be resumed has a pending status,
4000 then don't resume any threads - we can just report the pending
4001 status. Make sure to queue any signals that would otherwise be
4002 sent. In all-stop mode, we do this decision based on if *any*
4003 thread has a pending status. If there's a thread that needs the
4004 step-over-breakpoint dance, then don't resume any other thread
4005 but that particular one. */
4006 leave_pending
= (lwp
->status_pending_p
|| leave_all_stopped
);
4011 debug_printf ("resuming LWP %ld\n", lwpid_of (thread
));
4013 step
= (lwp
->resume
->kind
== resume_step
);
4014 linux_resume_one_lwp (lwp
, step
, lwp
->resume
->sig
, NULL
);
4019 debug_printf ("leaving LWP %ld stopped\n", lwpid_of (thread
));
4021 /* If we have a new signal, enqueue the signal. */
4022 if (lwp
->resume
->sig
!= 0)
4024 struct pending_signals
*p_sig
;
4025 p_sig
= xmalloc (sizeof (*p_sig
));
4026 p_sig
->prev
= lwp
->pending_signals
;
4027 p_sig
->signal
= lwp
->resume
->sig
;
4028 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
4030 /* If this is the same signal we were previously stopped by,
4031 make sure to queue its siginfo. We can ignore the return
4032 value of ptrace; if it fails, we'll skip
4033 PTRACE_SETSIGINFO. */
4034 if (WIFSTOPPED (lwp
->last_status
)
4035 && WSTOPSIG (lwp
->last_status
) == lwp
->resume
->sig
)
4036 ptrace (PTRACE_GETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
4039 lwp
->pending_signals
= p_sig
;
4043 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
4049 linux_resume (struct thread_resume
*resume_info
, size_t n
)
4051 struct thread_resume_array array
= { resume_info
, n
};
4052 struct thread_info
*need_step_over
= NULL
;
4054 int leave_all_stopped
;
4059 debug_printf ("linux_resume:\n");
4062 find_inferior (&all_threads
, linux_set_resume_request
, &array
);
4064 /* If there is a thread which would otherwise be resumed, which has
4065 a pending status, then don't resume any threads - we can just
4066 report the pending status. Make sure to queue any signals that
4067 would otherwise be sent. In non-stop mode, we'll apply this
4068 logic to each thread individually. We consume all pending events
4069 before considering to start a step-over (in all-stop). */
4072 find_inferior (&all_threads
, resume_status_pending_p
, &any_pending
);
4074 /* If there is a thread which would otherwise be resumed, which is
4075 stopped at a breakpoint that needs stepping over, then don't
4076 resume any threads - have it step over the breakpoint with all
4077 other threads stopped, then resume all threads again. Make sure
4078 to queue any signals that would otherwise be delivered or
4080 if (!any_pending
&& supports_breakpoints ())
4082 = (struct thread_info
*) find_inferior (&all_threads
,
4083 need_step_over_p
, NULL
);
4085 leave_all_stopped
= (need_step_over
!= NULL
|| any_pending
);
4089 if (need_step_over
!= NULL
)
4090 debug_printf ("Not resuming all, need step over\n");
4091 else if (any_pending
)
4092 debug_printf ("Not resuming, all-stop and found "
4093 "an LWP with pending status\n");
4095 debug_printf ("Resuming, no pending status or step over needed\n");
4098 /* Even if we're leaving threads stopped, queue all signals we'd
4099 otherwise deliver. */
4100 find_inferior (&all_threads
, linux_resume_one_thread
, &leave_all_stopped
);
4103 start_step_over (get_thread_lwp (need_step_over
));
4107 debug_printf ("linux_resume done\n");
4112 /* This function is called once per thread. We check the thread's
4113 last resume request, which will tell us whether to resume, step, or
4114 leave the thread stopped. Any signal the client requested to be
4115 delivered has already been enqueued at this point.
4117 If any thread that GDB wants running is stopped at an internal
4118 breakpoint that needs stepping over, we start a step-over operation
4119 on that particular thread, and leave all others stopped. */
4122 proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
4124 struct thread_info
*thread
= (struct thread_info
*) entry
;
4125 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4132 debug_printf ("proceed_one_lwp: lwp %ld\n", lwpid_of (thread
));
4137 debug_printf (" LWP %ld already running\n", lwpid_of (thread
));
4141 if (thread
->last_resume_kind
== resume_stop
4142 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
4145 debug_printf (" client wants LWP to remain %ld stopped\n",
4150 if (lwp
->status_pending_p
)
4153 debug_printf (" LWP %ld has pending status, leaving stopped\n",
4158 gdb_assert (lwp
->suspended
>= 0);
4163 debug_printf (" LWP %ld is suspended\n", lwpid_of (thread
));
4167 if (thread
->last_resume_kind
== resume_stop
4168 && lwp
->pending_signals_to_report
== NULL
4169 && lwp
->collecting_fast_tracepoint
== 0)
4171 /* We haven't reported this LWP as stopped yet (otherwise, the
4172 last_status.kind check above would catch it, and we wouldn't
4173 reach here. This LWP may have been momentarily paused by a
4174 stop_all_lwps call while handling for example, another LWP's
4175 step-over. In that case, the pending expected SIGSTOP signal
4176 that was queued at vCont;t handling time will have already
4177 been consumed by wait_for_sigstop, and so we need to requeue
4178 another one here. Note that if the LWP already has a SIGSTOP
4179 pending, this is a no-op. */
4182 debug_printf ("Client wants LWP %ld to stop. "
4183 "Making sure it has a SIGSTOP pending\n",
4189 step
= thread
->last_resume_kind
== resume_step
;
4190 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
4195 unsuspend_and_proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
4197 struct thread_info
*thread
= (struct thread_info
*) entry
;
4198 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4204 gdb_assert (lwp
->suspended
>= 0);
4206 return proceed_one_lwp (entry
, except
);
4209 /* When we finish a step-over, set threads running again. If there's
4210 another thread that may need a step-over, now's the time to start
4211 it. Eventually, we'll move all threads past their breakpoints. */
4214 proceed_all_lwps (void)
4216 struct thread_info
*need_step_over
;
4218 /* If there is a thread which would otherwise be resumed, which is
4219 stopped at a breakpoint that needs stepping over, then don't
4220 resume any threads - have it step over the breakpoint with all
4221 other threads stopped, then resume all threads again. */
4223 if (supports_breakpoints ())
4226 = (struct thread_info
*) find_inferior (&all_threads
,
4227 need_step_over_p
, NULL
);
4229 if (need_step_over
!= NULL
)
4232 debug_printf ("proceed_all_lwps: found "
4233 "thread %ld needing a step-over\n",
4234 lwpid_of (need_step_over
));
4236 start_step_over (get_thread_lwp (need_step_over
));
4242 debug_printf ("Proceeding, no step-over needed\n");
4244 find_inferior (&all_threads
, proceed_one_lwp
, NULL
);
4247 /* Stopped LWPs that the client wanted to be running, that don't have
4248 pending statuses, are set to run again, except for EXCEPT, if not
4249 NULL. This undoes a stop_all_lwps call. */
4252 unstop_all_lwps (int unsuspend
, struct lwp_info
*except
)
4258 debug_printf ("unstopping all lwps, except=(LWP %ld)\n",
4259 lwpid_of (get_lwp_thread (except
)));
4261 debug_printf ("unstopping all lwps\n");
4265 find_inferior (&all_threads
, unsuspend_and_proceed_one_lwp
, except
);
4267 find_inferior (&all_threads
, proceed_one_lwp
, except
);
4271 debug_printf ("unstop_all_lwps done\n");
4277 #ifdef HAVE_LINUX_REGSETS
4279 #define use_linux_regsets 1
4281 /* Returns true if REGSET has been disabled. */
4284 regset_disabled (struct regsets_info
*info
, struct regset_info
*regset
)
4286 return (info
->disabled_regsets
!= NULL
4287 && info
->disabled_regsets
[regset
- info
->regsets
]);
4290 /* Disable REGSET. */
4293 disable_regset (struct regsets_info
*info
, struct regset_info
*regset
)
4297 dr_offset
= regset
- info
->regsets
;
4298 if (info
->disabled_regsets
== NULL
)
4299 info
->disabled_regsets
= xcalloc (1, info
->num_regsets
);
4300 info
->disabled_regsets
[dr_offset
] = 1;
4304 regsets_fetch_inferior_registers (struct regsets_info
*regsets_info
,
4305 struct regcache
*regcache
)
4307 struct regset_info
*regset
;
4308 int saw_general_regs
= 0;
4312 pid
= lwpid_of (current_thread
);
4313 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
4318 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
))
4321 buf
= xmalloc (regset
->size
);
4323 nt_type
= regset
->nt_type
;
4327 iov
.iov_len
= regset
->size
;
4328 data
= (void *) &iov
;
4334 res
= ptrace (regset
->get_request
, pid
,
4335 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
4337 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
4343 /* If we get EIO on a regset, do not try it again for
4344 this process mode. */
4345 disable_regset (regsets_info
, regset
);
4347 else if (errno
== ENODATA
)
4349 /* ENODATA may be returned if the regset is currently
4350 not "active". This can happen in normal operation,
4351 so suppress the warning in this case. */
4356 sprintf (s
, "ptrace(regsets_fetch_inferior_registers) PID=%d",
4363 if (regset
->type
== GENERAL_REGS
)
4364 saw_general_regs
= 1;
4365 regset
->store_function (regcache
, buf
);
4369 if (saw_general_regs
)
4376 regsets_store_inferior_registers (struct regsets_info
*regsets_info
,
4377 struct regcache
*regcache
)
4379 struct regset_info
*regset
;
4380 int saw_general_regs
= 0;
4384 pid
= lwpid_of (current_thread
);
4385 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
4390 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
)
4391 || regset
->fill_function
== NULL
)
4394 buf
= xmalloc (regset
->size
);
4396 /* First fill the buffer with the current register set contents,
4397 in case there are any items in the kernel's regset that are
4398 not in gdbserver's regcache. */
4400 nt_type
= regset
->nt_type
;
4404 iov
.iov_len
= regset
->size
;
4405 data
= (void *) &iov
;
4411 res
= ptrace (regset
->get_request
, pid
,
4412 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
4414 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
4419 /* Then overlay our cached registers on that. */
4420 regset
->fill_function (regcache
, buf
);
4422 /* Only now do we write the register set. */
4424 res
= ptrace (regset
->set_request
, pid
,
4425 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
4427 res
= ptrace (regset
->set_request
, pid
, data
, nt_type
);
4435 /* If we get EIO on a regset, do not try it again for
4436 this process mode. */
4437 disable_regset (regsets_info
, regset
);
4439 else if (errno
== ESRCH
)
4441 /* At this point, ESRCH should mean the process is
4442 already gone, in which case we simply ignore attempts
4443 to change its registers. See also the related
4444 comment in linux_resume_one_lwp. */
4450 perror ("Warning: ptrace(regsets_store_inferior_registers)");
4453 else if (regset
->type
== GENERAL_REGS
)
4454 saw_general_regs
= 1;
4457 if (saw_general_regs
)
4463 #else /* !HAVE_LINUX_REGSETS */
4465 #define use_linux_regsets 0
4466 #define regsets_fetch_inferior_registers(regsets_info, regcache) 1
4467 #define regsets_store_inferior_registers(regsets_info, regcache) 1
4471 /* Return 1 if register REGNO is supported by one of the regset ptrace
4472 calls or 0 if it has to be transferred individually. */
4475 linux_register_in_regsets (const struct regs_info
*regs_info
, int regno
)
4477 unsigned char mask
= 1 << (regno
% 8);
4478 size_t index
= regno
/ 8;
4480 return (use_linux_regsets
4481 && (regs_info
->regset_bitmap
== NULL
4482 || (regs_info
->regset_bitmap
[index
] & mask
) != 0));
4485 #ifdef HAVE_LINUX_USRREGS
4488 register_addr (const struct usrregs_info
*usrregs
, int regnum
)
4492 if (regnum
< 0 || regnum
>= usrregs
->num_regs
)
4493 error ("Invalid register number %d.", regnum
);
4495 addr
= usrregs
->regmap
[regnum
];
4500 /* Fetch one register. */
4502 fetch_register (const struct usrregs_info
*usrregs
,
4503 struct regcache
*regcache
, int regno
)
4510 if (regno
>= usrregs
->num_regs
)
4512 if ((*the_low_target
.cannot_fetch_register
) (regno
))
4515 regaddr
= register_addr (usrregs
, regno
);
4519 size
= ((register_size (regcache
->tdesc
, regno
)
4520 + sizeof (PTRACE_XFER_TYPE
) - 1)
4521 & -sizeof (PTRACE_XFER_TYPE
));
4522 buf
= alloca (size
);
4524 pid
= lwpid_of (current_thread
);
4525 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
4528 *(PTRACE_XFER_TYPE
*) (buf
+ i
) =
4529 ptrace (PTRACE_PEEKUSER
, pid
,
4530 /* Coerce to a uintptr_t first to avoid potential gcc warning
4531 of coercing an 8 byte integer to a 4 byte pointer. */
4532 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
, (PTRACE_TYPE_ARG4
) 0);
4533 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
4535 error ("reading register %d: %s", regno
, strerror (errno
));
4538 if (the_low_target
.supply_ptrace_register
)
4539 the_low_target
.supply_ptrace_register (regcache
, regno
, buf
);
4541 supply_register (regcache
, regno
, buf
);
4544 /* Store one register. */
4546 store_register (const struct usrregs_info
*usrregs
,
4547 struct regcache
*regcache
, int regno
)
4554 if (regno
>= usrregs
->num_regs
)
4556 if ((*the_low_target
.cannot_store_register
) (regno
))
4559 regaddr
= register_addr (usrregs
, regno
);
4563 size
= ((register_size (regcache
->tdesc
, regno
)
4564 + sizeof (PTRACE_XFER_TYPE
) - 1)
4565 & -sizeof (PTRACE_XFER_TYPE
));
4566 buf
= alloca (size
);
4567 memset (buf
, 0, size
);
4569 if (the_low_target
.collect_ptrace_register
)
4570 the_low_target
.collect_ptrace_register (regcache
, regno
, buf
);
4572 collect_register (regcache
, regno
, buf
);
4574 pid
= lwpid_of (current_thread
);
4575 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
4578 ptrace (PTRACE_POKEUSER
, pid
,
4579 /* Coerce to a uintptr_t first to avoid potential gcc warning
4580 about coercing an 8 byte integer to a 4 byte pointer. */
4581 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
,
4582 (PTRACE_TYPE_ARG4
) *(PTRACE_XFER_TYPE
*) (buf
+ i
));
4585 /* At this point, ESRCH should mean the process is
4586 already gone, in which case we simply ignore attempts
4587 to change its registers. See also the related
4588 comment in linux_resume_one_lwp. */
4592 if ((*the_low_target
.cannot_store_register
) (regno
) == 0)
4593 error ("writing register %d: %s", regno
, strerror (errno
));
4595 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
4599 /* Fetch all registers, or just one, from the child process.
4600 If REGNO is -1, do this for all registers, skipping any that are
4601 assumed to have been retrieved by regsets_fetch_inferior_registers,
4602 unless ALL is non-zero.
4603 Otherwise, REGNO specifies which register (so we can save time). */
4605 usr_fetch_inferior_registers (const struct regs_info
*regs_info
,
4606 struct regcache
*regcache
, int regno
, int all
)
4608 struct usrregs_info
*usr
= regs_info
->usrregs
;
4612 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
4613 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
4614 fetch_register (usr
, regcache
, regno
);
4617 fetch_register (usr
, regcache
, regno
);
4620 /* Store our register values back into the inferior.
4621 If REGNO is -1, do this for all registers, skipping any that are
4622 assumed to have been saved by regsets_store_inferior_registers,
4623 unless ALL is non-zero.
4624 Otherwise, REGNO specifies which register (so we can save time). */
4626 usr_store_inferior_registers (const struct regs_info
*regs_info
,
4627 struct regcache
*regcache
, int regno
, int all
)
4629 struct usrregs_info
*usr
= regs_info
->usrregs
;
4633 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
4634 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
4635 store_register (usr
, regcache
, regno
);
4638 store_register (usr
, regcache
, regno
);
4641 #else /* !HAVE_LINUX_USRREGS */
4643 #define usr_fetch_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
4644 #define usr_store_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
4650 linux_fetch_registers (struct regcache
*regcache
, int regno
)
4654 const struct regs_info
*regs_info
= (*the_low_target
.regs_info
) ();
4658 if (the_low_target
.fetch_register
!= NULL
4659 && regs_info
->usrregs
!= NULL
)
4660 for (regno
= 0; regno
< regs_info
->usrregs
->num_regs
; regno
++)
4661 (*the_low_target
.fetch_register
) (regcache
, regno
);
4663 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
, regcache
);
4664 if (regs_info
->usrregs
!= NULL
)
4665 usr_fetch_inferior_registers (regs_info
, regcache
, -1, all
);
4669 if (the_low_target
.fetch_register
!= NULL
4670 && (*the_low_target
.fetch_register
) (regcache
, regno
))
4673 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
4675 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
,
4677 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
4678 usr_fetch_inferior_registers (regs_info
, regcache
, regno
, 1);
4683 linux_store_registers (struct regcache
*regcache
, int regno
)
4687 const struct regs_info
*regs_info
= (*the_low_target
.regs_info
) ();
4691 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
4693 if (regs_info
->usrregs
!= NULL
)
4694 usr_store_inferior_registers (regs_info
, regcache
, regno
, all
);
4698 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
4700 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
4702 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
4703 usr_store_inferior_registers (regs_info
, regcache
, regno
, 1);
4708 /* Copy LEN bytes from inferior's memory starting at MEMADDR
4709 to debugger memory starting at MYADDR. */
4712 linux_read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
, int len
)
4714 int pid
= lwpid_of (current_thread
);
4715 register PTRACE_XFER_TYPE
*buffer
;
4716 register CORE_ADDR addr
;
4723 /* Try using /proc. Don't bother for one word. */
4724 if (len
>= 3 * sizeof (long))
4728 /* We could keep this file open and cache it - possibly one per
4729 thread. That requires some juggling, but is even faster. */
4730 sprintf (filename
, "/proc/%d/mem", pid
);
4731 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
4735 /* If pread64 is available, use it. It's faster if the kernel
4736 supports it (only one syscall), and it's 64-bit safe even on
4737 32-bit platforms (for instance, SPARC debugging a SPARC64
4740 bytes
= pread64 (fd
, myaddr
, len
, memaddr
);
4743 if (lseek (fd
, memaddr
, SEEK_SET
) != -1)
4744 bytes
= read (fd
, myaddr
, len
);
4751 /* Some data was read, we'll try to get the rest with ptrace. */
4761 /* Round starting address down to longword boundary. */
4762 addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
4763 /* Round ending address up; get number of longwords that makes. */
4764 count
= ((((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
4765 / sizeof (PTRACE_XFER_TYPE
));
4766 /* Allocate buffer of that many longwords. */
4767 buffer
= (PTRACE_XFER_TYPE
*) alloca (count
* sizeof (PTRACE_XFER_TYPE
));
4769 /* Read all the longwords */
4771 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
4773 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
4774 about coercing an 8 byte integer to a 4 byte pointer. */
4775 buffer
[i
] = ptrace (PTRACE_PEEKTEXT
, pid
,
4776 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
4777 (PTRACE_TYPE_ARG4
) 0);
4783 /* Copy appropriate bytes out of the buffer. */
4786 i
*= sizeof (PTRACE_XFER_TYPE
);
4787 i
-= memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1);
4789 (char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
4796 /* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
4797 memory at MEMADDR. On failure (cannot write to the inferior)
4798 returns the value of errno. Always succeeds if LEN is zero. */
4801 linux_write_memory (CORE_ADDR memaddr
, const unsigned char *myaddr
, int len
)
4804 /* Round starting address down to longword boundary. */
4805 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
4806 /* Round ending address up; get number of longwords that makes. */
4808 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
4809 / sizeof (PTRACE_XFER_TYPE
);
4811 /* Allocate buffer of that many longwords. */
4812 register PTRACE_XFER_TYPE
*buffer
= (PTRACE_XFER_TYPE
*)
4813 alloca (count
* sizeof (PTRACE_XFER_TYPE
));
4815 int pid
= lwpid_of (current_thread
);
4819 /* Zero length write always succeeds. */
4825 /* Dump up to four bytes. */
4826 unsigned int val
= * (unsigned int *) myaddr
;
4832 val
= val
& 0xffffff;
4833 debug_printf ("Writing %0*x to 0x%08lx\n", 2 * ((len
< 4) ? len
: 4),
4834 val
, (long)memaddr
);
4837 /* Fill start and end extra bytes of buffer with existing memory data. */
4840 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
4841 about coercing an 8 byte integer to a 4 byte pointer. */
4842 buffer
[0] = ptrace (PTRACE_PEEKTEXT
, pid
,
4843 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
4844 (PTRACE_TYPE_ARG4
) 0);
4852 = ptrace (PTRACE_PEEKTEXT
, pid
,
4853 /* Coerce to a uintptr_t first to avoid potential gcc warning
4854 about coercing an 8 byte integer to a 4 byte pointer. */
4855 (PTRACE_TYPE_ARG3
) (uintptr_t) (addr
+ (count
- 1)
4856 * sizeof (PTRACE_XFER_TYPE
)),
4857 (PTRACE_TYPE_ARG4
) 0);
4862 /* Copy data to be written over corresponding part of buffer. */
4864 memcpy ((char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
4867 /* Write the entire buffer. */
4869 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
4872 ptrace (PTRACE_POKETEXT
, pid
,
4873 /* Coerce to a uintptr_t first to avoid potential gcc warning
4874 about coercing an 8 byte integer to a 4 byte pointer. */
4875 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
4876 (PTRACE_TYPE_ARG4
) buffer
[i
]);
4885 linux_look_up_symbols (void)
4887 #ifdef USE_THREAD_DB
4888 struct process_info
*proc
= current_process ();
4890 if (proc
->priv
->thread_db
!= NULL
)
4893 /* If the kernel supports tracing clones, then we don't need to
4894 use the magic thread event breakpoint to learn about
4896 thread_db_init (!linux_supports_traceclone ());
4901 linux_request_interrupt (void)
4903 extern unsigned long signal_pid
;
4905 /* Send a SIGINT to the process group. This acts just like the user
4906 typed a ^C on the controlling terminal. */
4907 kill (-signal_pid
, SIGINT
);
4910 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
4911 to debugger memory starting at MYADDR. */
4914 linux_read_auxv (CORE_ADDR offset
, unsigned char *myaddr
, unsigned int len
)
4916 char filename
[PATH_MAX
];
4918 int pid
= lwpid_of (current_thread
);
4920 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
4922 fd
= open (filename
, O_RDONLY
);
4926 if (offset
!= (CORE_ADDR
) 0
4927 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
4930 n
= read (fd
, myaddr
, len
);
4937 /* These breakpoint and watchpoint related wrapper functions simply
4938 pass on the function call if the target has registered a
4939 corresponding function. */
4942 linux_supports_z_point_type (char z_type
)
4944 return (the_low_target
.supports_z_point_type
!= NULL
4945 && the_low_target
.supports_z_point_type (z_type
));
4949 linux_insert_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
4950 int size
, struct raw_breakpoint
*bp
)
4952 if (the_low_target
.insert_point
!= NULL
)
4953 return the_low_target
.insert_point (type
, addr
, size
, bp
);
4955 /* Unsupported (see target.h). */
4960 linux_remove_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
4961 int size
, struct raw_breakpoint
*bp
)
4963 if (the_low_target
.remove_point
!= NULL
)
4964 return the_low_target
.remove_point (type
, addr
, size
, bp
);
4966 /* Unsupported (see target.h). */
4970 /* Implement the to_stopped_by_sw_breakpoint target_ops
4974 linux_stopped_by_sw_breakpoint (void)
4976 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
4978 return (lwp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
);
4981 /* Implement the to_supports_stopped_by_sw_breakpoint target_ops
4985 linux_supports_stopped_by_sw_breakpoint (void)
4987 return USE_SIGTRAP_SIGINFO
;
4990 /* Implement the to_stopped_by_hw_breakpoint target_ops
4994 linux_stopped_by_hw_breakpoint (void)
4996 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
4998 return (lwp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
);
5001 /* Implement the to_supports_stopped_by_hw_breakpoint target_ops
5005 linux_supports_stopped_by_hw_breakpoint (void)
5007 return USE_SIGTRAP_SIGINFO
;
5011 linux_stopped_by_watchpoint (void)
5013 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5015 return lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
;
5019 linux_stopped_data_address (void)
5021 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5023 return lwp
->stopped_data_address
;
5026 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
5027 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
5028 && defined(PT_TEXT_END_ADDR)
5030 /* This is only used for targets that define PT_TEXT_ADDR,
5031 PT_DATA_ADDR and PT_TEXT_END_ADDR. If those are not defined, supposedly
5032 the target has different ways of acquiring this information, like
5035 /* Under uClinux, programs are loaded at non-zero offsets, which we need
5036 to tell gdb about. */
5039 linux_read_offsets (CORE_ADDR
*text_p
, CORE_ADDR
*data_p
)
5041 unsigned long text
, text_end
, data
;
5042 int pid
= lwpid_of (get_thread_lwp (current_thread
));
5046 text
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_ADDR
,
5047 (PTRACE_TYPE_ARG4
) 0);
5048 text_end
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_END_ADDR
,
5049 (PTRACE_TYPE_ARG4
) 0);
5050 data
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_DATA_ADDR
,
5051 (PTRACE_TYPE_ARG4
) 0);
5055 /* Both text and data offsets produced at compile-time (and so
5056 used by gdb) are relative to the beginning of the program,
5057 with the data segment immediately following the text segment.
5058 However, the actual runtime layout in memory may put the data
5059 somewhere else, so when we send gdb a data base-address, we
5060 use the real data base address and subtract the compile-time
5061 data base-address from it (which is just the length of the
5062 text segment). BSS immediately follows data in both
5065 *data_p
= data
- (text_end
- text
);
5074 linux_qxfer_osdata (const char *annex
,
5075 unsigned char *readbuf
, unsigned const char *writebuf
,
5076 CORE_ADDR offset
, int len
)
5078 return linux_common_xfer_osdata (annex
, readbuf
, offset
, len
);
5081 /* Convert a native/host siginfo object, into/from the siginfo in the
5082 layout of the inferiors' architecture. */
5085 siginfo_fixup (siginfo_t
*siginfo
, void *inf_siginfo
, int direction
)
5089 if (the_low_target
.siginfo_fixup
!= NULL
)
5090 done
= the_low_target
.siginfo_fixup (siginfo
, inf_siginfo
, direction
);
5092 /* If there was no callback, or the callback didn't do anything,
5093 then just do a straight memcpy. */
5097 memcpy (siginfo
, inf_siginfo
, sizeof (siginfo_t
));
5099 memcpy (inf_siginfo
, siginfo
, sizeof (siginfo_t
));
5104 linux_xfer_siginfo (const char *annex
, unsigned char *readbuf
,
5105 unsigned const char *writebuf
, CORE_ADDR offset
, int len
)
5109 char inf_siginfo
[sizeof (siginfo_t
)];
5111 if (current_thread
== NULL
)
5114 pid
= lwpid_of (current_thread
);
5117 debug_printf ("%s siginfo for lwp %d.\n",
5118 readbuf
!= NULL
? "Reading" : "Writing",
5121 if (offset
>= sizeof (siginfo
))
5124 if (ptrace (PTRACE_GETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
5127 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
5128 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
5129 inferior with a 64-bit GDBSERVER should look the same as debugging it
5130 with a 32-bit GDBSERVER, we need to convert it. */
5131 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
5133 if (offset
+ len
> sizeof (siginfo
))
5134 len
= sizeof (siginfo
) - offset
;
5136 if (readbuf
!= NULL
)
5137 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
5140 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
5142 /* Convert back to ptrace layout before flushing it out. */
5143 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
5145 if (ptrace (PTRACE_SETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
5152 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
5153 so we notice when children change state; as the handler for the
5154 sigsuspend in my_waitpid. */
5157 sigchld_handler (int signo
)
5159 int old_errno
= errno
;
5165 /* fprintf is not async-signal-safe, so call write
5167 if (write (2, "sigchld_handler\n",
5168 sizeof ("sigchld_handler\n") - 1) < 0)
5169 break; /* just ignore */
5173 if (target_is_async_p ())
5174 async_file_mark (); /* trigger a linux_wait */
5180 linux_supports_non_stop (void)
5186 linux_async (int enable
)
5188 int previous
= target_is_async_p ();
5191 debug_printf ("linux_async (%d), previous=%d\n",
5194 if (previous
!= enable
)
5197 sigemptyset (&mask
);
5198 sigaddset (&mask
, SIGCHLD
);
5200 sigprocmask (SIG_BLOCK
, &mask
, NULL
);
5204 if (pipe (linux_event_pipe
) == -1)
5206 linux_event_pipe
[0] = -1;
5207 linux_event_pipe
[1] = -1;
5208 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
5210 warning ("creating event pipe failed.");
5214 fcntl (linux_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
5215 fcntl (linux_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
5217 /* Register the event loop handler. */
5218 add_file_handler (linux_event_pipe
[0],
5219 handle_target_event
, NULL
);
5221 /* Always trigger a linux_wait. */
5226 delete_file_handler (linux_event_pipe
[0]);
5228 close (linux_event_pipe
[0]);
5229 close (linux_event_pipe
[1]);
5230 linux_event_pipe
[0] = -1;
5231 linux_event_pipe
[1] = -1;
5234 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
5241 linux_start_non_stop (int nonstop
)
5243 /* Register or unregister from event-loop accordingly. */
5244 linux_async (nonstop
);
5246 if (target_is_async_p () != (nonstop
!= 0))
5253 linux_supports_multi_process (void)
5259 linux_supports_disable_randomization (void)
5261 #ifdef HAVE_PERSONALITY
5269 linux_supports_agent (void)
5275 linux_supports_range_stepping (void)
5277 if (*the_low_target
.supports_range_stepping
== NULL
)
5280 return (*the_low_target
.supports_range_stepping
) ();
5283 /* Enumerate spufs IDs for process PID. */
5285 spu_enumerate_spu_ids (long pid
, unsigned char *buf
, CORE_ADDR offset
, int len
)
5291 struct dirent
*entry
;
5293 sprintf (path
, "/proc/%ld/fd", pid
);
5294 dir
= opendir (path
);
5299 while ((entry
= readdir (dir
)) != NULL
)
5305 fd
= atoi (entry
->d_name
);
5309 sprintf (path
, "/proc/%ld/fd/%d", pid
, fd
);
5310 if (stat (path
, &st
) != 0)
5312 if (!S_ISDIR (st
.st_mode
))
5315 if (statfs (path
, &stfs
) != 0)
5317 if (stfs
.f_type
!= SPUFS_MAGIC
)
5320 if (pos
>= offset
&& pos
+ 4 <= offset
+ len
)
5322 *(unsigned int *)(buf
+ pos
- offset
) = fd
;
5332 /* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
5333 object type, using the /proc file system. */
5335 linux_qxfer_spu (const char *annex
, unsigned char *readbuf
,
5336 unsigned const char *writebuf
,
5337 CORE_ADDR offset
, int len
)
5339 long pid
= lwpid_of (current_thread
);
5344 if (!writebuf
&& !readbuf
)
5352 return spu_enumerate_spu_ids (pid
, readbuf
, offset
, len
);
5355 sprintf (buf
, "/proc/%ld/fd/%s", pid
, annex
);
5356 fd
= open (buf
, writebuf
? O_WRONLY
: O_RDONLY
);
5361 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
5368 ret
= write (fd
, writebuf
, (size_t) len
);
5370 ret
= read (fd
, readbuf
, (size_t) len
);
5376 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
5377 struct target_loadseg
5379 /* Core address to which the segment is mapped. */
5381 /* VMA recorded in the program header. */
5383 /* Size of this segment in memory. */
5387 # if defined PT_GETDSBT
5388 struct target_loadmap
5390 /* Protocol version number, must be zero. */
5392 /* Pointer to the DSBT table, its size, and the DSBT index. */
5393 unsigned *dsbt_table
;
5394 unsigned dsbt_size
, dsbt_index
;
5395 /* Number of segments in this map. */
5397 /* The actual memory map. */
5398 struct target_loadseg segs
[/*nsegs*/];
5400 # define LINUX_LOADMAP PT_GETDSBT
5401 # define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
5402 # define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
5404 struct target_loadmap
5406 /* Protocol version number, must be zero. */
5408 /* Number of segments in this map. */
5410 /* The actual memory map. */
5411 struct target_loadseg segs
[/*nsegs*/];
5413 # define LINUX_LOADMAP PTRACE_GETFDPIC
5414 # define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
5415 # define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
5419 linux_read_loadmap (const char *annex
, CORE_ADDR offset
,
5420 unsigned char *myaddr
, unsigned int len
)
5422 int pid
= lwpid_of (current_thread
);
5424 struct target_loadmap
*data
= NULL
;
5425 unsigned int actual_length
, copy_length
;
5427 if (strcmp (annex
, "exec") == 0)
5428 addr
= (int) LINUX_LOADMAP_EXEC
;
5429 else if (strcmp (annex
, "interp") == 0)
5430 addr
= (int) LINUX_LOADMAP_INTERP
;
5434 if (ptrace (LINUX_LOADMAP
, pid
, addr
, &data
) != 0)
5440 actual_length
= sizeof (struct target_loadmap
)
5441 + sizeof (struct target_loadseg
) * data
->nsegs
;
5443 if (offset
< 0 || offset
> actual_length
)
5446 copy_length
= actual_length
- offset
< len
? actual_length
- offset
: len
;
5447 memcpy (myaddr
, (char *) data
+ offset
, copy_length
);
5451 # define linux_read_loadmap NULL
5452 #endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
5455 linux_process_qsupported (const char *query
)
5457 if (the_low_target
.process_qsupported
!= NULL
)
5458 the_low_target
.process_qsupported (query
);
5462 linux_supports_tracepoints (void)
5464 if (*the_low_target
.supports_tracepoints
== NULL
)
5467 return (*the_low_target
.supports_tracepoints
) ();
5471 linux_read_pc (struct regcache
*regcache
)
5473 if (the_low_target
.get_pc
== NULL
)
5476 return (*the_low_target
.get_pc
) (regcache
);
5480 linux_write_pc (struct regcache
*regcache
, CORE_ADDR pc
)
5482 gdb_assert (the_low_target
.set_pc
!= NULL
);
5484 (*the_low_target
.set_pc
) (regcache
, pc
);
5488 linux_thread_stopped (struct thread_info
*thread
)
5490 return get_thread_lwp (thread
)->stopped
;
5493 /* This exposes stop-all-threads functionality to other modules. */
5496 linux_pause_all (int freeze
)
5498 stop_all_lwps (freeze
, NULL
);
5501 /* This exposes unstop-all-threads functionality to other gdbserver
5505 linux_unpause_all (int unfreeze
)
5507 unstop_all_lwps (unfreeze
, NULL
);
5511 linux_prepare_to_access_memory (void)
5513 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
5516 linux_pause_all (1);
5521 linux_done_accessing_memory (void)
5523 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
5526 linux_unpause_all (1);
5530 linux_install_fast_tracepoint_jump_pad (CORE_ADDR tpoint
, CORE_ADDR tpaddr
,
5531 CORE_ADDR collector
,
5534 CORE_ADDR
*jump_entry
,
5535 CORE_ADDR
*trampoline
,
5536 ULONGEST
*trampoline_size
,
5537 unsigned char *jjump_pad_insn
,
5538 ULONGEST
*jjump_pad_insn_size
,
5539 CORE_ADDR
*adjusted_insn_addr
,
5540 CORE_ADDR
*adjusted_insn_addr_end
,
5543 return (*the_low_target
.install_fast_tracepoint_jump_pad
)
5544 (tpoint
, tpaddr
, collector
, lockaddr
, orig_size
,
5545 jump_entry
, trampoline
, trampoline_size
,
5546 jjump_pad_insn
, jjump_pad_insn_size
,
5547 adjusted_insn_addr
, adjusted_insn_addr_end
,
5551 static struct emit_ops
*
5552 linux_emit_ops (void)
5554 if (the_low_target
.emit_ops
!= NULL
)
5555 return (*the_low_target
.emit_ops
) ();
5561 linux_get_min_fast_tracepoint_insn_len (void)
5563 return (*the_low_target
.get_min_fast_tracepoint_insn_len
) ();
5566 /* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
5569 get_phdr_phnum_from_proc_auxv (const int pid
, const int is_elf64
,
5570 CORE_ADDR
*phdr_memaddr
, int *num_phdr
)
5572 char filename
[PATH_MAX
];
5574 const int auxv_size
= is_elf64
5575 ? sizeof (Elf64_auxv_t
) : sizeof (Elf32_auxv_t
);
5576 char buf
[sizeof (Elf64_auxv_t
)]; /* The larger of the two. */
5578 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
5580 fd
= open (filename
, O_RDONLY
);
5586 while (read (fd
, buf
, auxv_size
) == auxv_size
5587 && (*phdr_memaddr
== 0 || *num_phdr
== 0))
5591 Elf64_auxv_t
*const aux
= (Elf64_auxv_t
*) buf
;
5593 switch (aux
->a_type
)
5596 *phdr_memaddr
= aux
->a_un
.a_val
;
5599 *num_phdr
= aux
->a_un
.a_val
;
5605 Elf32_auxv_t
*const aux
= (Elf32_auxv_t
*) buf
;
5607 switch (aux
->a_type
)
5610 *phdr_memaddr
= aux
->a_un
.a_val
;
5613 *num_phdr
= aux
->a_un
.a_val
;
5621 if (*phdr_memaddr
== 0 || *num_phdr
== 0)
5623 warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
5624 "phdr_memaddr = %ld, phdr_num = %d",
5625 (long) *phdr_memaddr
, *num_phdr
);
5632 /* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
5635 get_dynamic (const int pid
, const int is_elf64
)
5637 CORE_ADDR phdr_memaddr
, relocation
;
5639 unsigned char *phdr_buf
;
5640 const int phdr_size
= is_elf64
? sizeof (Elf64_Phdr
) : sizeof (Elf32_Phdr
);
5642 if (get_phdr_phnum_from_proc_auxv (pid
, is_elf64
, &phdr_memaddr
, &num_phdr
))
5645 gdb_assert (num_phdr
< 100); /* Basic sanity check. */
5646 phdr_buf
= alloca (num_phdr
* phdr_size
);
5648 if (linux_read_memory (phdr_memaddr
, phdr_buf
, num_phdr
* phdr_size
))
5651 /* Compute relocation: it is expected to be 0 for "regular" executables,
5652 non-zero for PIE ones. */
5654 for (i
= 0; relocation
== -1 && i
< num_phdr
; i
++)
5657 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5659 if (p
->p_type
== PT_PHDR
)
5660 relocation
= phdr_memaddr
- p
->p_vaddr
;
5664 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5666 if (p
->p_type
== PT_PHDR
)
5667 relocation
= phdr_memaddr
- p
->p_vaddr
;
5670 if (relocation
== -1)
5672 /* PT_PHDR is optional, but necessary for PIE in general. Fortunately
5673 any real world executables, including PIE executables, have always
5674 PT_PHDR present. PT_PHDR is not present in some shared libraries or
5675 in fpc (Free Pascal 2.4) binaries but neither of those have a need for
5676 or present DT_DEBUG anyway (fpc binaries are statically linked).
5678 Therefore if there exists DT_DEBUG there is always also PT_PHDR.
5680 GDB could find RELOCATION also from AT_ENTRY - e_entry. */
5685 for (i
= 0; i
< num_phdr
; i
++)
5689 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5691 if (p
->p_type
== PT_DYNAMIC
)
5692 return p
->p_vaddr
+ relocation
;
5696 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5698 if (p
->p_type
== PT_DYNAMIC
)
5699 return p
->p_vaddr
+ relocation
;
5706 /* Return &_r_debug in the inferior, or -1 if not present. Return value
5707 can be 0 if the inferior does not yet have the library list initialized.
5708 We look for DT_MIPS_RLD_MAP first. MIPS executables use this instead of
5709 DT_DEBUG, although they sometimes contain an unused DT_DEBUG entry too. */
5712 get_r_debug (const int pid
, const int is_elf64
)
5714 CORE_ADDR dynamic_memaddr
;
5715 const int dyn_size
= is_elf64
? sizeof (Elf64_Dyn
) : sizeof (Elf32_Dyn
);
5716 unsigned char buf
[sizeof (Elf64_Dyn
)]; /* The larger of the two. */
5719 dynamic_memaddr
= get_dynamic (pid
, is_elf64
);
5720 if (dynamic_memaddr
== 0)
5723 while (linux_read_memory (dynamic_memaddr
, buf
, dyn_size
) == 0)
5727 Elf64_Dyn
*const dyn
= (Elf64_Dyn
*) buf
;
5728 #ifdef DT_MIPS_RLD_MAP
5732 unsigned char buf
[sizeof (Elf64_Xword
)];
5736 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
5738 if (linux_read_memory (dyn
->d_un
.d_val
,
5739 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
5744 #endif /* DT_MIPS_RLD_MAP */
5746 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
5747 map
= dyn
->d_un
.d_val
;
5749 if (dyn
->d_tag
== DT_NULL
)
5754 Elf32_Dyn
*const dyn
= (Elf32_Dyn
*) buf
;
5755 #ifdef DT_MIPS_RLD_MAP
5759 unsigned char buf
[sizeof (Elf32_Word
)];
5763 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
5765 if (linux_read_memory (dyn
->d_un
.d_val
,
5766 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
5771 #endif /* DT_MIPS_RLD_MAP */
5773 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
5774 map
= dyn
->d_un
.d_val
;
5776 if (dyn
->d_tag
== DT_NULL
)
5780 dynamic_memaddr
+= dyn_size
;
5786 /* Read one pointer from MEMADDR in the inferior. */
5789 read_one_ptr (CORE_ADDR memaddr
, CORE_ADDR
*ptr
, int ptr_size
)
5793 /* Go through a union so this works on either big or little endian
5794 hosts, when the inferior's pointer size is smaller than the size
5795 of CORE_ADDR. It is assumed the inferior's endianness is the
5796 same of the superior's. */
5799 CORE_ADDR core_addr
;
5804 ret
= linux_read_memory (memaddr
, &addr
.uc
, ptr_size
);
5807 if (ptr_size
== sizeof (CORE_ADDR
))
5808 *ptr
= addr
.core_addr
;
5809 else if (ptr_size
== sizeof (unsigned int))
5812 gdb_assert_not_reached ("unhandled pointer size");
5817 struct link_map_offsets
5819 /* Offset and size of r_debug.r_version. */
5820 int r_version_offset
;
5822 /* Offset and size of r_debug.r_map. */
5825 /* Offset to l_addr field in struct link_map. */
5828 /* Offset to l_name field in struct link_map. */
5831 /* Offset to l_ld field in struct link_map. */
5834 /* Offset to l_next field in struct link_map. */
5837 /* Offset to l_prev field in struct link_map. */
5841 /* Construct qXfer:libraries-svr4:read reply. */
5844 linux_qxfer_libraries_svr4 (const char *annex
, unsigned char *readbuf
,
5845 unsigned const char *writebuf
,
5846 CORE_ADDR offset
, int len
)
5849 unsigned document_len
;
5850 struct process_info_private
*const priv
= current_process ()->priv
;
5851 char filename
[PATH_MAX
];
5854 static const struct link_map_offsets lmo_32bit_offsets
=
5856 0, /* r_version offset. */
5857 4, /* r_debug.r_map offset. */
5858 0, /* l_addr offset in link_map. */
5859 4, /* l_name offset in link_map. */
5860 8, /* l_ld offset in link_map. */
5861 12, /* l_next offset in link_map. */
5862 16 /* l_prev offset in link_map. */
5865 static const struct link_map_offsets lmo_64bit_offsets
=
5867 0, /* r_version offset. */
5868 8, /* r_debug.r_map offset. */
5869 0, /* l_addr offset in link_map. */
5870 8, /* l_name offset in link_map. */
5871 16, /* l_ld offset in link_map. */
5872 24, /* l_next offset in link_map. */
5873 32 /* l_prev offset in link_map. */
5875 const struct link_map_offsets
*lmo
;
5876 unsigned int machine
;
5878 CORE_ADDR lm_addr
= 0, lm_prev
= 0;
5879 int allocated
= 1024;
5881 CORE_ADDR l_name
, l_addr
, l_ld
, l_next
, l_prev
;
5882 int header_done
= 0;
5884 if (writebuf
!= NULL
)
5886 if (readbuf
== NULL
)
5889 pid
= lwpid_of (current_thread
);
5890 xsnprintf (filename
, sizeof filename
, "/proc/%d/exe", pid
);
5891 is_elf64
= elf_64_file_p (filename
, &machine
);
5892 lmo
= is_elf64
? &lmo_64bit_offsets
: &lmo_32bit_offsets
;
5893 ptr_size
= is_elf64
? 8 : 4;
5895 while (annex
[0] != '\0')
5901 sep
= strchr (annex
, '=');
5906 if (len
== 5 && strncmp (annex
, "start", 5) == 0)
5908 else if (len
== 4 && strncmp (annex
, "prev", 4) == 0)
5912 annex
= strchr (sep
, ';');
5919 annex
= decode_address_to_semicolon (addrp
, sep
+ 1);
5926 if (priv
->r_debug
== 0)
5927 priv
->r_debug
= get_r_debug (pid
, is_elf64
);
5929 /* We failed to find DT_DEBUG. Such situation will not change
5930 for this inferior - do not retry it. Report it to GDB as
5931 E01, see for the reasons at the GDB solib-svr4.c side. */
5932 if (priv
->r_debug
== (CORE_ADDR
) -1)
5935 if (priv
->r_debug
!= 0)
5937 if (linux_read_memory (priv
->r_debug
+ lmo
->r_version_offset
,
5938 (unsigned char *) &r_version
,
5939 sizeof (r_version
)) != 0
5942 warning ("unexpected r_debug version %d", r_version
);
5944 else if (read_one_ptr (priv
->r_debug
+ lmo
->r_map_offset
,
5945 &lm_addr
, ptr_size
) != 0)
5947 warning ("unable to read r_map from 0x%lx",
5948 (long) priv
->r_debug
+ lmo
->r_map_offset
);
5953 document
= xmalloc (allocated
);
5954 strcpy (document
, "<library-list-svr4 version=\"1.0\"");
5955 p
= document
+ strlen (document
);
5958 && read_one_ptr (lm_addr
+ lmo
->l_name_offset
,
5959 &l_name
, ptr_size
) == 0
5960 && read_one_ptr (lm_addr
+ lmo
->l_addr_offset
,
5961 &l_addr
, ptr_size
) == 0
5962 && read_one_ptr (lm_addr
+ lmo
->l_ld_offset
,
5963 &l_ld
, ptr_size
) == 0
5964 && read_one_ptr (lm_addr
+ lmo
->l_prev_offset
,
5965 &l_prev
, ptr_size
) == 0
5966 && read_one_ptr (lm_addr
+ lmo
->l_next_offset
,
5967 &l_next
, ptr_size
) == 0)
5969 unsigned char libname
[PATH_MAX
];
5971 if (lm_prev
!= l_prev
)
5973 warning ("Corrupted shared library list: 0x%lx != 0x%lx",
5974 (long) lm_prev
, (long) l_prev
);
5978 /* Ignore the first entry even if it has valid name as the first entry
5979 corresponds to the main executable. The first entry should not be
5980 skipped if the dynamic loader was loaded late by a static executable
5981 (see solib-svr4.c parameter ignore_first). But in such case the main
5982 executable does not have PT_DYNAMIC present and this function already
5983 exited above due to failed get_r_debug. */
5986 sprintf (p
, " main-lm=\"0x%lx\"", (unsigned long) lm_addr
);
5991 /* Not checking for error because reading may stop before
5992 we've got PATH_MAX worth of characters. */
5994 linux_read_memory (l_name
, libname
, sizeof (libname
) - 1);
5995 libname
[sizeof (libname
) - 1] = '\0';
5996 if (libname
[0] != '\0')
5998 /* 6x the size for xml_escape_text below. */
5999 size_t len
= 6 * strlen ((char *) libname
);
6004 /* Terminate `<library-list-svr4'. */
6009 while (allocated
< p
- document
+ len
+ 200)
6011 /* Expand to guarantee sufficient storage. */
6012 uintptr_t document_len
= p
- document
;
6014 document
= xrealloc (document
, 2 * allocated
);
6016 p
= document
+ document_len
;
6019 name
= xml_escape_text ((char *) libname
);
6020 p
+= sprintf (p
, "<library name=\"%s\" lm=\"0x%lx\" "
6021 "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
6022 name
, (unsigned long) lm_addr
,
6023 (unsigned long) l_addr
, (unsigned long) l_ld
);
6034 /* Empty list; terminate `<library-list-svr4'. */
6038 strcpy (p
, "</library-list-svr4>");
6040 document_len
= strlen (document
);
6041 if (offset
< document_len
)
6042 document_len
-= offset
;
6045 if (len
> document_len
)
6048 memcpy (readbuf
, document
+ offset
, len
);
6054 #ifdef HAVE_LINUX_BTRACE
6056 /* See to_enable_btrace target method. */
6058 static struct btrace_target_info
*
6059 linux_low_enable_btrace (ptid_t ptid
, const struct btrace_config
*conf
)
6061 struct btrace_target_info
*tinfo
;
6063 tinfo
= linux_enable_btrace (ptid
, conf
);
6065 if (tinfo
!= NULL
&& tinfo
->ptr_bits
== 0)
6067 struct thread_info
*thread
= find_thread_ptid (ptid
);
6068 struct regcache
*regcache
= get_thread_regcache (thread
, 0);
6070 tinfo
->ptr_bits
= register_size (regcache
->tdesc
, 0) * 8;
6076 /* See to_disable_btrace target method. */
6079 linux_low_disable_btrace (struct btrace_target_info
*tinfo
)
6081 enum btrace_error err
;
6083 err
= linux_disable_btrace (tinfo
);
6084 return (err
== BTRACE_ERR_NONE
? 0 : -1);
6087 /* See to_read_btrace target method. */
6090 linux_low_read_btrace (struct btrace_target_info
*tinfo
, struct buffer
*buffer
,
6093 struct btrace_data btrace
;
6094 struct btrace_block
*block
;
6095 enum btrace_error err
;
6098 btrace_data_init (&btrace
);
6100 err
= linux_read_btrace (&btrace
, tinfo
, type
);
6101 if (err
!= BTRACE_ERR_NONE
)
6103 if (err
== BTRACE_ERR_OVERFLOW
)
6104 buffer_grow_str0 (buffer
, "E.Overflow.");
6106 buffer_grow_str0 (buffer
, "E.Generic Error.");
6108 btrace_data_fini (&btrace
);
6112 switch (btrace
.format
)
6114 case BTRACE_FORMAT_NONE
:
6115 buffer_grow_str0 (buffer
, "E.No Trace.");
6118 case BTRACE_FORMAT_BTS
:
6119 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
6120 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
6123 VEC_iterate (btrace_block_s
, btrace
.variant
.bts
.blocks
, i
, block
);
6125 buffer_xml_printf (buffer
, "<block begin=\"0x%s\" end=\"0x%s\"/>\n",
6126 paddress (block
->begin
), paddress (block
->end
));
6128 buffer_grow_str0 (buffer
, "</btrace>\n");
6132 buffer_grow_str0 (buffer
, "E.Unknown Trace Format.");
6134 btrace_data_fini (&btrace
);
6138 btrace_data_fini (&btrace
);
6142 /* See to_btrace_conf target method. */
6145 linux_low_btrace_conf (const struct btrace_target_info
*tinfo
,
6146 struct buffer
*buffer
)
6148 const struct btrace_config
*conf
;
6150 buffer_grow_str (buffer
, "<!DOCTYPE btrace-conf SYSTEM \"btrace-conf.dtd\">\n");
6151 buffer_grow_str (buffer
, "<btrace-conf version=\"1.0\">\n");
6153 conf
= linux_btrace_conf (tinfo
);
6156 switch (conf
->format
)
6158 case BTRACE_FORMAT_NONE
:
6161 case BTRACE_FORMAT_BTS
:
6162 buffer_xml_printf (buffer
, "<bts");
6163 buffer_xml_printf (buffer
, " size=\"0x%x\"", conf
->bts
.size
);
6164 buffer_xml_printf (buffer
, " />\n");
6169 buffer_grow_str0 (buffer
, "</btrace-conf>\n");
6172 #endif /* HAVE_LINUX_BTRACE */
6174 static struct target_ops linux_target_ops
= {
6175 linux_create_inferior
,
6184 linux_fetch_registers
,
6185 linux_store_registers
,
6186 linux_prepare_to_access_memory
,
6187 linux_done_accessing_memory
,
6190 linux_look_up_symbols
,
6191 linux_request_interrupt
,
6193 linux_supports_z_point_type
,
6196 linux_stopped_by_sw_breakpoint
,
6197 linux_supports_stopped_by_sw_breakpoint
,
6198 linux_stopped_by_hw_breakpoint
,
6199 linux_supports_stopped_by_hw_breakpoint
,
6200 linux_stopped_by_watchpoint
,
6201 linux_stopped_data_address
,
6202 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
6203 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
6204 && defined(PT_TEXT_END_ADDR)
6209 #ifdef USE_THREAD_DB
6210 thread_db_get_tls_address
,
6215 hostio_last_error_from_errno
,
6218 linux_supports_non_stop
,
6220 linux_start_non_stop
,
6221 linux_supports_multi_process
,
6222 #ifdef USE_THREAD_DB
6223 thread_db_handle_monitor_command
,
6227 linux_common_core_of_thread
,
6229 linux_process_qsupported
,
6230 linux_supports_tracepoints
,
6233 linux_thread_stopped
,
6237 linux_stabilize_threads
,
6238 linux_install_fast_tracepoint_jump_pad
,
6240 linux_supports_disable_randomization
,
6241 linux_get_min_fast_tracepoint_insn_len
,
6242 linux_qxfer_libraries_svr4
,
6243 linux_supports_agent
,
6244 #ifdef HAVE_LINUX_BTRACE
6245 linux_supports_btrace
,
6246 linux_low_enable_btrace
,
6247 linux_low_disable_btrace
,
6248 linux_low_read_btrace
,
6249 linux_low_btrace_conf
,
6257 linux_supports_range_stepping
,
6261 linux_init_signals ()
6263 /* FIXME drow/2002-06-09: As above, we should check with LinuxThreads
6264 to find what the cancel signal actually is. */
6265 #ifndef __ANDROID__ /* Bionic doesn't use SIGRTMIN the way glibc does. */
6266 signal (__SIGRTMIN
+1, SIG_IGN
);
6270 #ifdef HAVE_LINUX_REGSETS
6272 initialize_regsets_info (struct regsets_info
*info
)
6274 for (info
->num_regsets
= 0;
6275 info
->regsets
[info
->num_regsets
].size
>= 0;
6276 info
->num_regsets
++)
6282 initialize_low (void)
6284 struct sigaction sigchld_action
;
6285 memset (&sigchld_action
, 0, sizeof (sigchld_action
));
6286 set_target_ops (&linux_target_ops
);
6287 set_breakpoint_data (the_low_target
.breakpoint
,
6288 the_low_target
.breakpoint_len
);
6289 linux_init_signals ();
6290 linux_ptrace_init_warnings ();
6292 sigchld_action
.sa_handler
= sigchld_handler
;
6293 sigemptyset (&sigchld_action
.sa_mask
);
6294 sigchld_action
.sa_flags
= SA_RESTART
;
6295 sigaction (SIGCHLD
, &sigchld_action
, NULL
);
6297 initialize_low_arch ();