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
;
2241 struct lwp_info
*lp
= get_thread_lwp (thread
);
2244 gdb_assert (count
!= NULL
);
2246 /* Count only resumed LWPs that have an event pending. */
2247 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2248 && lp
->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 an event. */
2273 select_event_lwp_callback (struct inferior_list_entry
*entry
, void *data
)
2275 struct thread_info
*thread
= (struct thread_info
*) entry
;
2276 struct lwp_info
*lp
= get_thread_lwp (thread
);
2277 int *selector
= data
;
2279 gdb_assert (selector
!= NULL
);
2281 /* Select only resumed LWPs that have an event pending. */
2282 if (thread
->last_status
.kind
== TARGET_WAITKIND_IGNORE
2283 && lp
->status_pending_p
)
2284 if ((*selector
)-- == 0)
2290 /* Select one LWP out of those that have events pending. */
2293 select_event_lwp (struct lwp_info
**orig_lp
)
2296 int random_selector
;
2297 struct thread_info
*event_thread
= NULL
;
2299 /* In all-stop, give preference to the LWP that is being
2300 single-stepped. There will be at most one, and it's the LWP that
2301 the core is most interested in. If we didn't do this, then we'd
2302 have to handle pending step SIGTRAPs somehow in case the core
2303 later continues the previously-stepped thread, otherwise we'd
2304 report the pending SIGTRAP, and the core, not having stepped the
2305 thread, wouldn't understand what the trap was for, and therefore
2306 would report it to the user as a random signal. */
2310 = (struct thread_info
*) find_inferior (&all_threads
,
2311 select_singlestep_lwp_callback
,
2313 if (event_thread
!= NULL
)
2316 debug_printf ("SEL: Select single-step %s\n",
2317 target_pid_to_str (ptid_of (event_thread
)));
2320 if (event_thread
== NULL
)
2322 /* No single-stepping LWP. Select one at random, out of those
2323 which have had events. */
2325 /* First see how many events we have. */
2326 find_inferior (&all_threads
, count_events_callback
, &num_events
);
2327 gdb_assert (num_events
> 0);
2329 /* Now randomly pick a LWP out of those that have had
2331 random_selector
= (int)
2332 ((num_events
* (double) rand ()) / (RAND_MAX
+ 1.0));
2334 if (debug_threads
&& num_events
> 1)
2335 debug_printf ("SEL: Found %d SIGTRAP events, selecting #%d\n",
2336 num_events
, random_selector
);
2339 = (struct thread_info
*) find_inferior (&all_threads
,
2340 select_event_lwp_callback
,
2344 if (event_thread
!= NULL
)
2346 struct lwp_info
*event_lp
= get_thread_lwp (event_thread
);
2348 /* Switch the event LWP. */
2349 *orig_lp
= event_lp
;
2353 /* Decrement the suspend count of an LWP. */
2356 unsuspend_one_lwp (struct inferior_list_entry
*entry
, void *except
)
2358 struct thread_info
*thread
= (struct thread_info
*) entry
;
2359 struct lwp_info
*lwp
= get_thread_lwp (thread
);
2361 /* Ignore EXCEPT. */
2367 gdb_assert (lwp
->suspended
>= 0);
2371 /* Decrement the suspend count of all LWPs, except EXCEPT, if non
2375 unsuspend_all_lwps (struct lwp_info
*except
)
2377 find_inferior (&all_threads
, unsuspend_one_lwp
, except
);
2380 static void move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
);
2381 static int stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
,
2383 static int lwp_running (struct inferior_list_entry
*entry
, void *data
);
2384 static ptid_t
linux_wait_1 (ptid_t ptid
,
2385 struct target_waitstatus
*ourstatus
,
2386 int target_options
);
2388 /* Stabilize threads (move out of jump pads).
2390 If a thread is midway collecting a fast tracepoint, we need to
2391 finish the collection and move it out of the jump pad before
2392 reporting the signal.
2394 This avoids recursion while collecting (when a signal arrives
2395 midway, and the signal handler itself collects), which would trash
2396 the trace buffer. In case the user set a breakpoint in a signal
2397 handler, this avoids the backtrace showing the jump pad, etc..
2398 Most importantly, there are certain things we can't do safely if
2399 threads are stopped in a jump pad (or in its callee's). For
2402 - starting a new trace run. A thread still collecting the
2403 previous run, could trash the trace buffer when resumed. The trace
2404 buffer control structures would have been reset but the thread had
2405 no way to tell. The thread could even midway memcpy'ing to the
2406 buffer, which would mean that when resumed, it would clobber the
2407 trace buffer that had been set for a new run.
2409 - we can't rewrite/reuse the jump pads for new tracepoints
2410 safely. Say you do tstart while a thread is stopped midway while
2411 collecting. When the thread is later resumed, it finishes the
2412 collection, and returns to the jump pad, to execute the original
2413 instruction that was under the tracepoint jump at the time the
2414 older run had been started. If the jump pad had been rewritten
2415 since for something else in the new run, the thread would now
2416 execute the wrong / random instructions. */
2419 linux_stabilize_threads (void)
2421 struct thread_info
*saved_thread
;
2422 struct thread_info
*thread_stuck
;
2425 = (struct thread_info
*) find_inferior (&all_threads
,
2426 stuck_in_jump_pad_callback
,
2428 if (thread_stuck
!= NULL
)
2431 debug_printf ("can't stabilize, LWP %ld is stuck in jump pad\n",
2432 lwpid_of (thread_stuck
));
2436 saved_thread
= current_thread
;
2438 stabilizing_threads
= 1;
2441 for_each_inferior (&all_threads
, move_out_of_jump_pad_callback
);
2443 /* Loop until all are stopped out of the jump pads. */
2444 while (find_inferior (&all_threads
, lwp_running
, NULL
) != NULL
)
2446 struct target_waitstatus ourstatus
;
2447 struct lwp_info
*lwp
;
2450 /* Note that we go through the full wait even loop. While
2451 moving threads out of jump pad, we need to be able to step
2452 over internal breakpoints and such. */
2453 linux_wait_1 (minus_one_ptid
, &ourstatus
, 0);
2455 if (ourstatus
.kind
== TARGET_WAITKIND_STOPPED
)
2457 lwp
= get_thread_lwp (current_thread
);
2462 if (ourstatus
.value
.sig
!= GDB_SIGNAL_0
2463 || current_thread
->last_resume_kind
== resume_stop
)
2465 wstat
= W_STOPCODE (gdb_signal_to_host (ourstatus
.value
.sig
));
2466 enqueue_one_deferred_signal (lwp
, &wstat
);
2471 find_inferior (&all_threads
, unsuspend_one_lwp
, NULL
);
2473 stabilizing_threads
= 0;
2475 current_thread
= saved_thread
;
2480 = (struct thread_info
*) find_inferior (&all_threads
,
2481 stuck_in_jump_pad_callback
,
2483 if (thread_stuck
!= NULL
)
2484 debug_printf ("couldn't stabilize, LWP %ld got stuck in jump pad\n",
2485 lwpid_of (thread_stuck
));
2489 static void async_file_mark (void);
2491 /* Convenience function that is called when the kernel reports an
2492 event that is not passed out to GDB. */
2495 ignore_event (struct target_waitstatus
*ourstatus
)
2497 /* If we got an event, there may still be others, as a single
2498 SIGCHLD can indicate more than one child stopped. This forces
2499 another target_wait call. */
2502 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2506 /* Wait for process, returns status. */
2509 linux_wait_1 (ptid_t ptid
,
2510 struct target_waitstatus
*ourstatus
, int target_options
)
2513 struct lwp_info
*event_child
;
2516 int step_over_finished
;
2517 int bp_explains_trap
;
2518 int maybe_internal_trap
;
2526 debug_printf ("linux_wait_1: [%s]\n", target_pid_to_str (ptid
));
2529 /* Translate generic target options into linux options. */
2531 if (target_options
& TARGET_WNOHANG
)
2534 bp_explains_trap
= 0;
2537 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2539 if (ptid_equal (step_over_bkpt
, null_ptid
))
2540 pid
= linux_wait_for_event (ptid
, &w
, options
);
2544 debug_printf ("step_over_bkpt set [%s], doing a blocking wait\n",
2545 target_pid_to_str (step_over_bkpt
));
2546 pid
= linux_wait_for_event (step_over_bkpt
, &w
, options
& ~WNOHANG
);
2551 gdb_assert (target_options
& TARGET_WNOHANG
);
2555 debug_printf ("linux_wait_1 ret = null_ptid, "
2556 "TARGET_WAITKIND_IGNORE\n");
2560 ourstatus
->kind
= TARGET_WAITKIND_IGNORE
;
2567 debug_printf ("linux_wait_1 ret = null_ptid, "
2568 "TARGET_WAITKIND_NO_RESUMED\n");
2572 ourstatus
->kind
= TARGET_WAITKIND_NO_RESUMED
;
2576 event_child
= get_thread_lwp (current_thread
);
2578 /* linux_wait_for_event only returns an exit status for the last
2579 child of a process. Report it. */
2580 if (WIFEXITED (w
) || WIFSIGNALED (w
))
2584 ourstatus
->kind
= TARGET_WAITKIND_EXITED
;
2585 ourstatus
->value
.integer
= WEXITSTATUS (w
);
2589 debug_printf ("linux_wait_1 ret = %s, exited with "
2591 target_pid_to_str (ptid_of (current_thread
)),
2598 ourstatus
->kind
= TARGET_WAITKIND_SIGNALLED
;
2599 ourstatus
->value
.sig
= gdb_signal_from_host (WTERMSIG (w
));
2603 debug_printf ("linux_wait_1 ret = %s, terminated with "
2605 target_pid_to_str (ptid_of (current_thread
)),
2611 return ptid_of (current_thread
);
2614 /* If step-over executes a breakpoint instruction, it means a
2615 gdb/gdbserver breakpoint had been planted on top of a permanent
2616 breakpoint. The PC has been adjusted by
2617 check_stopped_by_breakpoint to point at the breakpoint address.
2618 Advance the PC manually past the breakpoint, otherwise the
2619 program would keep trapping the permanent breakpoint forever. */
2620 if (!ptid_equal (step_over_bkpt
, null_ptid
)
2621 && event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
)
2623 unsigned int increment_pc
= the_low_target
.breakpoint_len
;
2627 debug_printf ("step-over for %s executed software breakpoint\n",
2628 target_pid_to_str (ptid_of (current_thread
)));
2631 if (increment_pc
!= 0)
2633 struct regcache
*regcache
2634 = get_thread_regcache (current_thread
, 1);
2636 event_child
->stop_pc
+= increment_pc
;
2637 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
2639 if (!(*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))
2640 event_child
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
2644 /* If this event was not handled before, and is not a SIGTRAP, we
2645 report it. SIGILL and SIGSEGV are also treated as traps in case
2646 a breakpoint is inserted at the current PC. If this target does
2647 not support internal breakpoints at all, we also report the
2648 SIGTRAP without further processing; it's of no concern to us. */
2650 = (supports_breakpoints ()
2651 && (WSTOPSIG (w
) == SIGTRAP
2652 || ((WSTOPSIG (w
) == SIGILL
2653 || WSTOPSIG (w
) == SIGSEGV
)
2654 && (*the_low_target
.breakpoint_at
) (event_child
->stop_pc
))));
2656 if (maybe_internal_trap
)
2658 /* Handle anything that requires bookkeeping before deciding to
2659 report the event or continue waiting. */
2661 /* First check if we can explain the SIGTRAP with an internal
2662 breakpoint, or if we should possibly report the event to GDB.
2663 Do this before anything that may remove or insert a
2665 bp_explains_trap
= breakpoint_inserted_here (event_child
->stop_pc
);
2667 /* We have a SIGTRAP, possibly a step-over dance has just
2668 finished. If so, tweak the state machine accordingly,
2669 reinsert breakpoints and delete any reinsert (software
2670 single-step) breakpoints. */
2671 step_over_finished
= finish_step_over (event_child
);
2673 /* Now invoke the callbacks of any internal breakpoints there. */
2674 check_breakpoints (event_child
->stop_pc
);
2676 /* Handle tracepoint data collecting. This may overflow the
2677 trace buffer, and cause a tracing stop, removing
2679 trace_event
= handle_tracepoints (event_child
);
2681 if (bp_explains_trap
)
2683 /* If we stepped or ran into an internal breakpoint, we've
2684 already handled it. So next time we resume (from this
2685 PC), we should step over it. */
2687 debug_printf ("Hit a gdbserver breakpoint.\n");
2689 if (breakpoint_here (event_child
->stop_pc
))
2690 event_child
->need_step_over
= 1;
2695 /* We have some other signal, possibly a step-over dance was in
2696 progress, and it should be cancelled too. */
2697 step_over_finished
= finish_step_over (event_child
);
2700 /* We have all the data we need. Either report the event to GDB, or
2701 resume threads and keep waiting for more. */
2703 /* If we're collecting a fast tracepoint, finish the collection and
2704 move out of the jump pad before delivering a signal. See
2705 linux_stabilize_threads. */
2708 && WSTOPSIG (w
) != SIGTRAP
2709 && supports_fast_tracepoints ()
2710 && agent_loaded_p ())
2713 debug_printf ("Got signal %d for LWP %ld. Check if we need "
2714 "to defer or adjust it.\n",
2715 WSTOPSIG (w
), lwpid_of (current_thread
));
2717 /* Allow debugging the jump pad itself. */
2718 if (current_thread
->last_resume_kind
!= resume_step
2719 && maybe_move_out_of_jump_pad (event_child
, &w
))
2721 enqueue_one_deferred_signal (event_child
, &w
);
2724 debug_printf ("Signal %d for LWP %ld deferred (in jump pad)\n",
2725 WSTOPSIG (w
), lwpid_of (current_thread
));
2727 linux_resume_one_lwp (event_child
, 0, 0, NULL
);
2729 return ignore_event (ourstatus
);
2733 if (event_child
->collecting_fast_tracepoint
)
2736 debug_printf ("LWP %ld was trying to move out of the jump pad (%d). "
2737 "Check if we're already there.\n",
2738 lwpid_of (current_thread
),
2739 event_child
->collecting_fast_tracepoint
);
2743 event_child
->collecting_fast_tracepoint
2744 = linux_fast_tracepoint_collecting (event_child
, NULL
);
2746 if (event_child
->collecting_fast_tracepoint
!= 1)
2748 /* No longer need this breakpoint. */
2749 if (event_child
->exit_jump_pad_bkpt
!= NULL
)
2752 debug_printf ("No longer need exit-jump-pad bkpt; removing it."
2753 "stopping all threads momentarily.\n");
2755 /* Other running threads could hit this breakpoint.
2756 We don't handle moribund locations like GDB does,
2757 instead we always pause all threads when removing
2758 breakpoints, so that any step-over or
2759 decr_pc_after_break adjustment is always taken
2760 care of while the breakpoint is still
2762 stop_all_lwps (1, event_child
);
2764 delete_breakpoint (event_child
->exit_jump_pad_bkpt
);
2765 event_child
->exit_jump_pad_bkpt
= NULL
;
2767 unstop_all_lwps (1, event_child
);
2769 gdb_assert (event_child
->suspended
>= 0);
2773 if (event_child
->collecting_fast_tracepoint
== 0)
2776 debug_printf ("fast tracepoint finished "
2777 "collecting successfully.\n");
2779 /* We may have a deferred signal to report. */
2780 if (dequeue_one_deferred_signal (event_child
, &w
))
2783 debug_printf ("dequeued one signal.\n");
2788 debug_printf ("no deferred signals.\n");
2790 if (stabilizing_threads
)
2792 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
2793 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
2797 debug_printf ("linux_wait_1 ret = %s, stopped "
2798 "while stabilizing threads\n",
2799 target_pid_to_str (ptid_of (current_thread
)));
2803 return ptid_of (current_thread
);
2809 /* Check whether GDB would be interested in this event. */
2811 /* If GDB is not interested in this signal, don't stop other
2812 threads, and don't report it to GDB. Just resume the inferior
2813 right away. We do this for threading-related signals as well as
2814 any that GDB specifically requested we ignore. But never ignore
2815 SIGSTOP if we sent it ourselves, and do not ignore signals when
2816 stepping - they may require special handling to skip the signal
2817 handler. Also never ignore signals that could be caused by a
2819 /* FIXME drow/2002-06-09: Get signal numbers from the inferior's
2822 && current_thread
->last_resume_kind
!= resume_step
2824 #if defined (USE_THREAD_DB) && !defined (__ANDROID__)
2825 (current_process ()->priv
->thread_db
!= NULL
2826 && (WSTOPSIG (w
) == __SIGRTMIN
2827 || WSTOPSIG (w
) == __SIGRTMIN
+ 1))
2830 (pass_signals
[gdb_signal_from_host (WSTOPSIG (w
))]
2831 && !(WSTOPSIG (w
) == SIGSTOP
2832 && current_thread
->last_resume_kind
== resume_stop
)
2833 && !linux_wstatus_maybe_breakpoint (w
))))
2835 siginfo_t info
, *info_p
;
2838 debug_printf ("Ignored signal %d for LWP %ld.\n",
2839 WSTOPSIG (w
), lwpid_of (current_thread
));
2841 if (ptrace (PTRACE_GETSIGINFO
, lwpid_of (current_thread
),
2842 (PTRACE_TYPE_ARG3
) 0, &info
) == 0)
2846 linux_resume_one_lwp (event_child
, event_child
->stepping
,
2847 WSTOPSIG (w
), info_p
);
2848 return ignore_event (ourstatus
);
2851 /* Note that all addresses are always "out of the step range" when
2852 there's no range to begin with. */
2853 in_step_range
= lwp_in_step_range (event_child
);
2855 /* If GDB wanted this thread to single step, and the thread is out
2856 of the step range, we always want to report the SIGTRAP, and let
2857 GDB handle it. Watchpoints should always be reported. So should
2858 signals we can't explain. A SIGTRAP we can't explain could be a
2859 GDB breakpoint --- we may or not support Z0 breakpoints. If we
2860 do, we're be able to handle GDB breakpoints on top of internal
2861 breakpoints, by handling the internal breakpoint and still
2862 reporting the event to GDB. If we don't, we're out of luck, GDB
2863 won't see the breakpoint hit. */
2864 report_to_gdb
= (!maybe_internal_trap
2865 || (current_thread
->last_resume_kind
== resume_step
2867 || event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
2868 || (!step_over_finished
&& !in_step_range
2869 && !bp_explains_trap
&& !trace_event
)
2870 || (gdb_breakpoint_here (event_child
->stop_pc
)
2871 && gdb_condition_true_at_breakpoint (event_child
->stop_pc
)
2872 && gdb_no_commands_at_breakpoint (event_child
->stop_pc
)));
2874 run_breakpoint_commands (event_child
->stop_pc
);
2876 /* We found no reason GDB would want us to stop. We either hit one
2877 of our own breakpoints, or finished an internal step GDB
2878 shouldn't know about. */
2883 if (bp_explains_trap
)
2884 debug_printf ("Hit a gdbserver breakpoint.\n");
2885 if (step_over_finished
)
2886 debug_printf ("Step-over finished.\n");
2888 debug_printf ("Tracepoint event.\n");
2889 if (lwp_in_step_range (event_child
))
2890 debug_printf ("Range stepping pc 0x%s [0x%s, 0x%s).\n",
2891 paddress (event_child
->stop_pc
),
2892 paddress (event_child
->step_range_start
),
2893 paddress (event_child
->step_range_end
));
2896 /* We're not reporting this breakpoint to GDB, so apply the
2897 decr_pc_after_break adjustment to the inferior's regcache
2900 if (the_low_target
.set_pc
!= NULL
)
2902 struct regcache
*regcache
2903 = get_thread_regcache (current_thread
, 1);
2904 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
);
2907 /* We may have finished stepping over a breakpoint. If so,
2908 we've stopped and suspended all LWPs momentarily except the
2909 stepping one. This is where we resume them all again. We're
2910 going to keep waiting, so use proceed, which handles stepping
2911 over the next breakpoint. */
2913 debug_printf ("proceeding all threads.\n");
2915 if (step_over_finished
)
2916 unsuspend_all_lwps (event_child
);
2918 proceed_all_lwps ();
2919 return ignore_event (ourstatus
);
2924 if (current_thread
->last_resume_kind
== resume_step
)
2926 if (event_child
->step_range_start
== event_child
->step_range_end
)
2927 debug_printf ("GDB wanted to single-step, reporting event.\n");
2928 else if (!lwp_in_step_range (event_child
))
2929 debug_printf ("Out of step range, reporting event.\n");
2931 if (event_child
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
)
2932 debug_printf ("Stopped by watchpoint.\n");
2933 else if (gdb_breakpoint_here (event_child
->stop_pc
))
2934 debug_printf ("Stopped by GDB breakpoint.\n");
2936 debug_printf ("Hit a non-gdbserver trap event.\n");
2939 /* Alright, we're going to report a stop. */
2941 if (!stabilizing_threads
)
2943 /* In all-stop, stop all threads. */
2945 stop_all_lwps (0, NULL
);
2947 /* If we're not waiting for a specific LWP, choose an event LWP
2948 from among those that have had events. Giving equal priority
2949 to all LWPs that have had events helps prevent
2951 if (ptid_equal (ptid
, minus_one_ptid
))
2953 event_child
->status_pending_p
= 1;
2954 event_child
->status_pending
= w
;
2956 select_event_lwp (&event_child
);
2958 /* current_thread and event_child must stay in sync. */
2959 current_thread
= get_lwp_thread (event_child
);
2961 event_child
->status_pending_p
= 0;
2962 w
= event_child
->status_pending
;
2965 if (step_over_finished
)
2969 /* If we were doing a step-over, all other threads but
2970 the stepping one had been paused in start_step_over,
2971 with their suspend counts incremented. We don't want
2972 to do a full unstop/unpause, because we're in
2973 all-stop mode (so we want threads stopped), but we
2974 still need to unsuspend the other threads, to
2975 decrement their `suspended' count back. */
2976 unsuspend_all_lwps (event_child
);
2980 /* If we just finished a step-over, then all threads had
2981 been momentarily paused. In all-stop, that's fine,
2982 we want threads stopped by now anyway. In non-stop,
2983 we need to re-resume threads that GDB wanted to be
2985 unstop_all_lwps (1, event_child
);
2989 /* Stabilize threads (move out of jump pads). */
2991 stabilize_threads ();
2995 /* If we just finished a step-over, then all threads had been
2996 momentarily paused. In all-stop, that's fine, we want
2997 threads stopped by now anyway. In non-stop, we need to
2998 re-resume threads that GDB wanted to be running. */
2999 if (step_over_finished
)
3000 unstop_all_lwps (1, event_child
);
3003 ourstatus
->kind
= TARGET_WAITKIND_STOPPED
;
3005 /* Now that we've selected our final event LWP, un-adjust its PC if
3006 it was a software breakpoint, and the client doesn't know we can
3007 adjust the breakpoint ourselves. */
3008 if (event_child
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
3009 && !swbreak_feature
)
3011 int decr_pc
= the_low_target
.decr_pc_after_break
;
3015 struct regcache
*regcache
3016 = get_thread_regcache (current_thread
, 1);
3017 (*the_low_target
.set_pc
) (regcache
, event_child
->stop_pc
+ decr_pc
);
3021 if (current_thread
->last_resume_kind
== resume_stop
3022 && WSTOPSIG (w
) == SIGSTOP
)
3024 /* A thread that has been requested to stop by GDB with vCont;t,
3025 and it stopped cleanly, so report as SIG0. The use of
3026 SIGSTOP is an implementation detail. */
3027 ourstatus
->value
.sig
= GDB_SIGNAL_0
;
3029 else if (current_thread
->last_resume_kind
== resume_stop
3030 && WSTOPSIG (w
) != SIGSTOP
)
3032 /* A thread that has been requested to stop by GDB with vCont;t,
3033 but, it stopped for other reasons. */
3034 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
3038 ourstatus
->value
.sig
= gdb_signal_from_host (WSTOPSIG (w
));
3041 gdb_assert (ptid_equal (step_over_bkpt
, null_ptid
));
3045 debug_printf ("linux_wait_1 ret = %s, %d, %d\n",
3046 target_pid_to_str (ptid_of (current_thread
)),
3047 ourstatus
->kind
, ourstatus
->value
.sig
);
3051 return ptid_of (current_thread
);
3054 /* Get rid of any pending event in the pipe. */
3056 async_file_flush (void)
3062 ret
= read (linux_event_pipe
[0], &buf
, 1);
3063 while (ret
>= 0 || (ret
== -1 && errno
== EINTR
));
3066 /* Put something in the pipe, so the event loop wakes up. */
3068 async_file_mark (void)
3072 async_file_flush ();
3075 ret
= write (linux_event_pipe
[1], "+", 1);
3076 while (ret
== 0 || (ret
== -1 && errno
== EINTR
));
3078 /* Ignore EAGAIN. If the pipe is full, the event loop will already
3079 be awakened anyway. */
3083 linux_wait (ptid_t ptid
,
3084 struct target_waitstatus
*ourstatus
, int target_options
)
3088 /* Flush the async file first. */
3089 if (target_is_async_p ())
3090 async_file_flush ();
3094 event_ptid
= linux_wait_1 (ptid
, ourstatus
, target_options
);
3096 while ((target_options
& TARGET_WNOHANG
) == 0
3097 && ptid_equal (event_ptid
, null_ptid
)
3098 && ourstatus
->kind
== TARGET_WAITKIND_IGNORE
);
3100 /* If at least one stop was reported, there may be more. A single
3101 SIGCHLD can signal more than one child stop. */
3102 if (target_is_async_p ()
3103 && (target_options
& TARGET_WNOHANG
) != 0
3104 && !ptid_equal (event_ptid
, null_ptid
))
3110 /* Send a signal to an LWP. */
3113 kill_lwp (unsigned long lwpid
, int signo
)
3115 /* Use tkill, if possible, in case we are using nptl threads. If tkill
3116 fails, then we are not using nptl threads and we should be using kill. */
3120 static int tkill_failed
;
3127 ret
= syscall (__NR_tkill
, lwpid
, signo
);
3128 if (errno
!= ENOSYS
)
3135 return kill (lwpid
, signo
);
3139 linux_stop_lwp (struct lwp_info
*lwp
)
3145 send_sigstop (struct lwp_info
*lwp
)
3149 pid
= lwpid_of (get_lwp_thread (lwp
));
3151 /* If we already have a pending stop signal for this process, don't
3153 if (lwp
->stop_expected
)
3156 debug_printf ("Have pending sigstop for lwp %d\n", pid
);
3162 debug_printf ("Sending sigstop to lwp %d\n", pid
);
3164 lwp
->stop_expected
= 1;
3165 kill_lwp (pid
, SIGSTOP
);
3169 send_sigstop_callback (struct inferior_list_entry
*entry
, void *except
)
3171 struct thread_info
*thread
= (struct thread_info
*) entry
;
3172 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3174 /* Ignore EXCEPT. */
3185 /* Increment the suspend count of an LWP, and stop it, if not stopped
3188 suspend_and_send_sigstop_callback (struct inferior_list_entry
*entry
,
3191 struct thread_info
*thread
= (struct thread_info
*) entry
;
3192 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3194 /* Ignore EXCEPT. */
3200 return send_sigstop_callback (entry
, except
);
3204 mark_lwp_dead (struct lwp_info
*lwp
, int wstat
)
3206 /* It's dead, really. */
3209 /* Store the exit status for later. */
3210 lwp
->status_pending_p
= 1;
3211 lwp
->status_pending
= wstat
;
3213 /* Prevent trying to stop it. */
3216 /* No further stops are expected from a dead lwp. */
3217 lwp
->stop_expected
= 0;
3220 /* Wait for all children to stop for the SIGSTOPs we just queued. */
3223 wait_for_sigstop (void)
3225 struct thread_info
*saved_thread
;
3230 saved_thread
= current_thread
;
3231 if (saved_thread
!= NULL
)
3232 saved_tid
= saved_thread
->entry
.id
;
3234 saved_tid
= null_ptid
; /* avoid bogus unused warning */
3237 debug_printf ("wait_for_sigstop: pulling events\n");
3239 /* Passing NULL_PTID as filter indicates we want all events to be
3240 left pending. Eventually this returns when there are no
3241 unwaited-for children left. */
3242 ret
= linux_wait_for_event_filtered (minus_one_ptid
, null_ptid
,
3244 gdb_assert (ret
== -1);
3246 if (saved_thread
== NULL
|| linux_thread_alive (saved_tid
))
3247 current_thread
= saved_thread
;
3251 debug_printf ("Previously current thread died.\n");
3255 /* We can't change the current inferior behind GDB's back,
3256 otherwise, a subsequent command may apply to the wrong
3258 current_thread
= NULL
;
3262 /* Set a valid thread as current. */
3263 set_desired_thread (0);
3268 /* Returns true if LWP ENTRY is stopped in a jump pad, and we can't
3269 move it out, because we need to report the stop event to GDB. For
3270 example, if the user puts a breakpoint in the jump pad, it's
3271 because she wants to debug it. */
3274 stuck_in_jump_pad_callback (struct inferior_list_entry
*entry
, void *data
)
3276 struct thread_info
*thread
= (struct thread_info
*) entry
;
3277 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3279 gdb_assert (lwp
->suspended
== 0);
3280 gdb_assert (lwp
->stopped
);
3282 /* Allow debugging the jump pad, gdb_collect, etc.. */
3283 return (supports_fast_tracepoints ()
3284 && agent_loaded_p ()
3285 && (gdb_breakpoint_here (lwp
->stop_pc
)
3286 || lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
3287 || thread
->last_resume_kind
== resume_step
)
3288 && linux_fast_tracepoint_collecting (lwp
, NULL
));
3292 move_out_of_jump_pad_callback (struct inferior_list_entry
*entry
)
3294 struct thread_info
*thread
= (struct thread_info
*) entry
;
3295 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3298 gdb_assert (lwp
->suspended
== 0);
3299 gdb_assert (lwp
->stopped
);
3301 wstat
= lwp
->status_pending_p
? &lwp
->status_pending
: NULL
;
3303 /* Allow debugging the jump pad, gdb_collect, etc. */
3304 if (!gdb_breakpoint_here (lwp
->stop_pc
)
3305 && lwp
->stop_reason
!= TARGET_STOPPED_BY_WATCHPOINT
3306 && thread
->last_resume_kind
!= resume_step
3307 && maybe_move_out_of_jump_pad (lwp
, wstat
))
3310 debug_printf ("LWP %ld needs stabilizing (in jump pad)\n",
3315 lwp
->status_pending_p
= 0;
3316 enqueue_one_deferred_signal (lwp
, wstat
);
3319 debug_printf ("Signal %d for LWP %ld deferred "
3321 WSTOPSIG (*wstat
), lwpid_of (thread
));
3324 linux_resume_one_lwp (lwp
, 0, 0, NULL
);
3331 lwp_running (struct inferior_list_entry
*entry
, void *data
)
3333 struct thread_info
*thread
= (struct thread_info
*) entry
;
3334 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3343 /* Stop all lwps that aren't stopped yet, except EXCEPT, if not NULL.
3344 If SUSPEND, then also increase the suspend count of every LWP,
3348 stop_all_lwps (int suspend
, struct lwp_info
*except
)
3350 /* Should not be called recursively. */
3351 gdb_assert (stopping_threads
== NOT_STOPPING_THREADS
);
3356 debug_printf ("stop_all_lwps (%s, except=%s)\n",
3357 suspend
? "stop-and-suspend" : "stop",
3359 ? target_pid_to_str (ptid_of (get_lwp_thread (except
)))
3363 stopping_threads
= (suspend
3364 ? STOPPING_AND_SUSPENDING_THREADS
3365 : STOPPING_THREADS
);
3368 find_inferior (&all_threads
, suspend_and_send_sigstop_callback
, except
);
3370 find_inferior (&all_threads
, send_sigstop_callback
, except
);
3371 wait_for_sigstop ();
3372 stopping_threads
= NOT_STOPPING_THREADS
;
3376 debug_printf ("stop_all_lwps done, setting stopping_threads "
3377 "back to !stopping\n");
3382 /* Resume execution of LWP. If STEP is nonzero, single-step it. If
3383 SIGNAL is nonzero, give it that signal. */
3386 linux_resume_one_lwp_throw (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
);
3568 lwp
->stepping
= step
;
3569 ptrace (step
? PTRACE_SINGLESTEP
: PTRACE_CONT
, lwpid_of (thread
),
3570 (PTRACE_TYPE_ARG3
) 0,
3571 /* Coerce to a uintptr_t first to avoid potential gcc warning
3572 of coercing an 8 byte integer to a 4 byte pointer. */
3573 (PTRACE_TYPE_ARG4
) (uintptr_t) signal
);
3575 current_thread
= saved_thread
;
3577 perror_with_name ("resuming thread");
3579 /* Successfully resumed. Clear state that no longer makes sense,
3580 and mark the LWP as running. Must not do this before resuming
3581 otherwise if that fails other code will be confused. E.g., we'd
3582 later try to stop the LWP and hang forever waiting for a stop
3583 status. Note that we must not throw after this is cleared,
3584 otherwise handle_zombie_lwp_error would get confused. */
3586 lwp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3589 /* Called when we try to resume a stopped LWP and that errors out. If
3590 the LWP is no longer in ptrace-stopped state (meaning it's zombie,
3591 or about to become), discard the error, clear any pending status
3592 the LWP may have, and return true (we'll collect the exit status
3593 soon enough). Otherwise, return false. */
3596 check_ptrace_stopped_lwp_gone (struct lwp_info
*lp
)
3598 struct thread_info
*thread
= get_lwp_thread (lp
);
3600 /* If we get an error after resuming the LWP successfully, we'd
3601 confuse !T state for the LWP being gone. */
3602 gdb_assert (lp
->stopped
);
3604 /* We can't just check whether the LWP is in 'Z (Zombie)' state,
3605 because even if ptrace failed with ESRCH, the tracee may be "not
3606 yet fully dead", but already refusing ptrace requests. In that
3607 case the tracee has 'R (Running)' state for a little bit
3608 (observed in Linux 3.18). See also the note on ESRCH in the
3609 ptrace(2) man page. Instead, check whether the LWP has any state
3610 other than ptrace-stopped. */
3612 /* Don't assume anything if /proc/PID/status can't be read. */
3613 if (linux_proc_pid_is_trace_stopped_nowarn (lwpid_of (thread
)) == 0)
3615 lp
->stop_reason
= TARGET_STOPPED_BY_NO_REASON
;
3616 lp
->status_pending_p
= 0;
3622 /* Like linux_resume_one_lwp_throw, but no error is thrown if the LWP
3623 disappears while we try to resume it. */
3626 linux_resume_one_lwp (struct lwp_info
*lwp
,
3627 int step
, int signal
, siginfo_t
*info
)
3631 linux_resume_one_lwp_throw (lwp
, step
, signal
, info
);
3633 CATCH (ex
, RETURN_MASK_ERROR
)
3635 if (!check_ptrace_stopped_lwp_gone (lwp
))
3636 throw_exception (ex
);
3641 struct thread_resume_array
3643 struct thread_resume
*resume
;
3647 /* This function is called once per thread via find_inferior.
3648 ARG is a pointer to a thread_resume_array struct.
3649 We look up the thread specified by ENTRY in ARG, and mark the thread
3650 with a pointer to the appropriate resume request.
3652 This algorithm is O(threads * resume elements), but resume elements
3653 is small (and will remain small at least until GDB supports thread
3657 linux_set_resume_request (struct inferior_list_entry
*entry
, void *arg
)
3659 struct thread_info
*thread
= (struct thread_info
*) entry
;
3660 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3662 struct thread_resume_array
*r
;
3666 for (ndx
= 0; ndx
< r
->n
; ndx
++)
3668 ptid_t ptid
= r
->resume
[ndx
].thread
;
3669 if (ptid_equal (ptid
, minus_one_ptid
)
3670 || ptid_equal (ptid
, entry
->id
)
3671 /* Handle both 'pPID' and 'pPID.-1' as meaning 'all threads
3673 || (ptid_get_pid (ptid
) == pid_of (thread
)
3674 && (ptid_is_pid (ptid
)
3675 || ptid_get_lwp (ptid
) == -1)))
3677 if (r
->resume
[ndx
].kind
== resume_stop
3678 && thread
->last_resume_kind
== resume_stop
)
3681 debug_printf ("already %s LWP %ld at GDB's request\n",
3682 (thread
->last_status
.kind
3683 == TARGET_WAITKIND_STOPPED
)
3691 lwp
->resume
= &r
->resume
[ndx
];
3692 thread
->last_resume_kind
= lwp
->resume
->kind
;
3694 lwp
->step_range_start
= lwp
->resume
->step_range_start
;
3695 lwp
->step_range_end
= lwp
->resume
->step_range_end
;
3697 /* If we had a deferred signal to report, dequeue one now.
3698 This can happen if LWP gets more than one signal while
3699 trying to get out of a jump pad. */
3701 && !lwp
->status_pending_p
3702 && dequeue_one_deferred_signal (lwp
, &lwp
->status_pending
))
3704 lwp
->status_pending_p
= 1;
3707 debug_printf ("Dequeueing deferred signal %d for LWP %ld, "
3708 "leaving status pending.\n",
3709 WSTOPSIG (lwp
->status_pending
),
3717 /* No resume action for this thread. */
3723 /* find_inferior callback for linux_resume.
3724 Set *FLAG_P if this lwp has an interesting status pending. */
3727 resume_status_pending_p (struct inferior_list_entry
*entry
, void *flag_p
)
3729 struct thread_info
*thread
= (struct thread_info
*) entry
;
3730 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3732 /* LWPs which will not be resumed are not interesting, because
3733 we might not wait for them next time through linux_wait. */
3734 if (lwp
->resume
== NULL
)
3737 if (thread_still_has_status_pending_p (thread
))
3738 * (int *) flag_p
= 1;
3743 /* Return 1 if this lwp that GDB wants running is stopped at an
3744 internal breakpoint that we need to step over. It assumes that any
3745 required STOP_PC adjustment has already been propagated to the
3746 inferior's regcache. */
3749 need_step_over_p (struct inferior_list_entry
*entry
, void *dummy
)
3751 struct thread_info
*thread
= (struct thread_info
*) entry
;
3752 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3753 struct thread_info
*saved_thread
;
3756 /* LWPs which will not be resumed are not interesting, because we
3757 might not wait for them next time through linux_wait. */
3762 debug_printf ("Need step over [LWP %ld]? Ignoring, not stopped\n",
3767 if (thread
->last_resume_kind
== resume_stop
)
3770 debug_printf ("Need step over [LWP %ld]? Ignoring, should remain"
3776 gdb_assert (lwp
->suspended
>= 0);
3781 debug_printf ("Need step over [LWP %ld]? Ignoring, suspended\n",
3786 if (!lwp
->need_step_over
)
3789 debug_printf ("Need step over [LWP %ld]? No\n", lwpid_of (thread
));
3792 if (lwp
->status_pending_p
)
3795 debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
3801 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
3805 /* If the PC has changed since we stopped, then don't do anything,
3806 and let the breakpoint/tracepoint be hit. This happens if, for
3807 instance, GDB handled the decr_pc_after_break subtraction itself,
3808 GDB is OOL stepping this thread, or the user has issued a "jump"
3809 command, or poked thread's registers herself. */
3810 if (pc
!= lwp
->stop_pc
)
3813 debug_printf ("Need step over [LWP %ld]? Cancelling, PC was changed. "
3814 "Old stop_pc was 0x%s, PC is now 0x%s\n",
3816 paddress (lwp
->stop_pc
), paddress (pc
));
3818 lwp
->need_step_over
= 0;
3822 saved_thread
= current_thread
;
3823 current_thread
= thread
;
3825 /* We can only step over breakpoints we know about. */
3826 if (breakpoint_here (pc
) || fast_tracepoint_jump_here (pc
))
3828 /* Don't step over a breakpoint that GDB expects to hit
3829 though. If the condition is being evaluated on the target's side
3830 and it evaluate to false, step over this breakpoint as well. */
3831 if (gdb_breakpoint_here (pc
)
3832 && gdb_condition_true_at_breakpoint (pc
)
3833 && gdb_no_commands_at_breakpoint (pc
))
3836 debug_printf ("Need step over [LWP %ld]? yes, but found"
3837 " GDB breakpoint at 0x%s; skipping step over\n",
3838 lwpid_of (thread
), paddress (pc
));
3840 current_thread
= saved_thread
;
3846 debug_printf ("Need step over [LWP %ld]? yes, "
3847 "found breakpoint at 0x%s\n",
3848 lwpid_of (thread
), paddress (pc
));
3850 /* We've found an lwp that needs stepping over --- return 1 so
3851 that find_inferior stops looking. */
3852 current_thread
= saved_thread
;
3854 /* If the step over is cancelled, this is set again. */
3855 lwp
->need_step_over
= 0;
3860 current_thread
= saved_thread
;
3863 debug_printf ("Need step over [LWP %ld]? No, no breakpoint found"
3865 lwpid_of (thread
), paddress (pc
));
3870 /* Start a step-over operation on LWP. When LWP stopped at a
3871 breakpoint, to make progress, we need to remove the breakpoint out
3872 of the way. If we let other threads run while we do that, they may
3873 pass by the breakpoint location and miss hitting it. To avoid
3874 that, a step-over momentarily stops all threads while LWP is
3875 single-stepped while the breakpoint is temporarily uninserted from
3876 the inferior. When the single-step finishes, we reinsert the
3877 breakpoint, and let all threads that are supposed to be running,
3880 On targets that don't support hardware single-step, we don't
3881 currently support full software single-stepping. Instead, we only
3882 support stepping over the thread event breakpoint, by asking the
3883 low target where to place a reinsert breakpoint. Since this
3884 routine assumes the breakpoint being stepped over is a thread event
3885 breakpoint, it usually assumes the return address of the current
3886 function is a good enough place to set the reinsert breakpoint. */
3889 start_step_over (struct lwp_info
*lwp
)
3891 struct thread_info
*thread
= get_lwp_thread (lwp
);
3892 struct thread_info
*saved_thread
;
3897 debug_printf ("Starting step-over on LWP %ld. Stopping all threads\n",
3900 stop_all_lwps (1, lwp
);
3901 gdb_assert (lwp
->suspended
== 0);
3904 debug_printf ("Done stopping all threads for step-over.\n");
3906 /* Note, we should always reach here with an already adjusted PC,
3907 either by GDB (if we're resuming due to GDB's request), or by our
3908 caller, if we just finished handling an internal breakpoint GDB
3909 shouldn't care about. */
3912 saved_thread
= current_thread
;
3913 current_thread
= thread
;
3915 lwp
->bp_reinsert
= pc
;
3916 uninsert_breakpoints_at (pc
);
3917 uninsert_fast_tracepoint_jumps_at (pc
);
3919 if (can_hardware_single_step ())
3925 CORE_ADDR raddr
= (*the_low_target
.breakpoint_reinsert_addr
) ();
3926 set_reinsert_breakpoint (raddr
);
3930 current_thread
= saved_thread
;
3932 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
3934 /* Require next event from this LWP. */
3935 step_over_bkpt
= thread
->entry
.id
;
3939 /* Finish a step-over. Reinsert the breakpoint we had uninserted in
3940 start_step_over, if still there, and delete any reinsert
3941 breakpoints we've set, on non hardware single-step targets. */
3944 finish_step_over (struct lwp_info
*lwp
)
3946 if (lwp
->bp_reinsert
!= 0)
3949 debug_printf ("Finished step over.\n");
3951 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
3952 may be no breakpoint to reinsert there by now. */
3953 reinsert_breakpoints_at (lwp
->bp_reinsert
);
3954 reinsert_fast_tracepoint_jumps_at (lwp
->bp_reinsert
);
3956 lwp
->bp_reinsert
= 0;
3958 /* Delete any software-single-step reinsert breakpoints. No
3959 longer needed. We don't have to worry about other threads
3960 hitting this trap, and later not being able to explain it,
3961 because we were stepping over a breakpoint, and we hold all
3962 threads but LWP stopped while doing that. */
3963 if (!can_hardware_single_step ())
3964 delete_reinsert_breakpoints ();
3966 step_over_bkpt
= null_ptid
;
3973 /* This function is called once per thread. We check the thread's resume
3974 request, which will tell us whether to resume, step, or leave the thread
3975 stopped; and what signal, if any, it should be sent.
3977 For threads which we aren't explicitly told otherwise, we preserve
3978 the stepping flag; this is used for stepping over gdbserver-placed
3981 If pending_flags was set in any thread, we queue any needed
3982 signals, since we won't actually resume. We already have a pending
3983 event to report, so we don't need to preserve any step requests;
3984 they should be re-issued if necessary. */
3987 linux_resume_one_thread (struct inferior_list_entry
*entry
, void *arg
)
3989 struct thread_info
*thread
= (struct thread_info
*) entry
;
3990 struct lwp_info
*lwp
= get_thread_lwp (thread
);
3992 int leave_all_stopped
= * (int *) arg
;
3995 if (lwp
->resume
== NULL
)
3998 if (lwp
->resume
->kind
== resume_stop
)
4001 debug_printf ("resume_stop request for LWP %ld\n", lwpid_of (thread
));
4006 debug_printf ("stopping LWP %ld\n", lwpid_of (thread
));
4008 /* Stop the thread, and wait for the event asynchronously,
4009 through the event loop. */
4015 debug_printf ("already stopped LWP %ld\n",
4018 /* The LWP may have been stopped in an internal event that
4019 was not meant to be notified back to GDB (e.g., gdbserver
4020 breakpoint), so we should be reporting a stop event in
4023 /* If the thread already has a pending SIGSTOP, this is a
4024 no-op. Otherwise, something later will presumably resume
4025 the thread and this will cause it to cancel any pending
4026 operation, due to last_resume_kind == resume_stop. If
4027 the thread already has a pending status to report, we
4028 will still report it the next time we wait - see
4029 status_pending_p_callback. */
4031 /* If we already have a pending signal to report, then
4032 there's no need to queue a SIGSTOP, as this means we're
4033 midway through moving the LWP out of the jumppad, and we
4034 will report the pending signal as soon as that is
4036 if (lwp
->pending_signals_to_report
== NULL
)
4040 /* For stop requests, we're done. */
4042 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
4046 /* If this thread which is about to be resumed has a pending status,
4047 then don't resume any threads - we can just report the pending
4048 status. Make sure to queue any signals that would otherwise be
4049 sent. In all-stop mode, we do this decision based on if *any*
4050 thread has a pending status. If there's a thread that needs the
4051 step-over-breakpoint dance, then don't resume any other thread
4052 but that particular one. */
4053 leave_pending
= (lwp
->status_pending_p
|| leave_all_stopped
);
4058 debug_printf ("resuming LWP %ld\n", lwpid_of (thread
));
4060 step
= (lwp
->resume
->kind
== resume_step
);
4061 linux_resume_one_lwp (lwp
, step
, lwp
->resume
->sig
, NULL
);
4066 debug_printf ("leaving LWP %ld stopped\n", lwpid_of (thread
));
4068 /* If we have a new signal, enqueue the signal. */
4069 if (lwp
->resume
->sig
!= 0)
4071 struct pending_signals
*p_sig
;
4072 p_sig
= xmalloc (sizeof (*p_sig
));
4073 p_sig
->prev
= lwp
->pending_signals
;
4074 p_sig
->signal
= lwp
->resume
->sig
;
4075 memset (&p_sig
->info
, 0, sizeof (siginfo_t
));
4077 /* If this is the same signal we were previously stopped by,
4078 make sure to queue its siginfo. We can ignore the return
4079 value of ptrace; if it fails, we'll skip
4080 PTRACE_SETSIGINFO. */
4081 if (WIFSTOPPED (lwp
->last_status
)
4082 && WSTOPSIG (lwp
->last_status
) == lwp
->resume
->sig
)
4083 ptrace (PTRACE_GETSIGINFO
, lwpid_of (thread
), (PTRACE_TYPE_ARG3
) 0,
4086 lwp
->pending_signals
= p_sig
;
4090 thread
->last_status
.kind
= TARGET_WAITKIND_IGNORE
;
4096 linux_resume (struct thread_resume
*resume_info
, size_t n
)
4098 struct thread_resume_array array
= { resume_info
, n
};
4099 struct thread_info
*need_step_over
= NULL
;
4101 int leave_all_stopped
;
4106 debug_printf ("linux_resume:\n");
4109 find_inferior (&all_threads
, linux_set_resume_request
, &array
);
4111 /* If there is a thread which would otherwise be resumed, which has
4112 a pending status, then don't resume any threads - we can just
4113 report the pending status. Make sure to queue any signals that
4114 would otherwise be sent. In non-stop mode, we'll apply this
4115 logic to each thread individually. We consume all pending events
4116 before considering to start a step-over (in all-stop). */
4119 find_inferior (&all_threads
, resume_status_pending_p
, &any_pending
);
4121 /* If there is a thread which would otherwise be resumed, which is
4122 stopped at a breakpoint that needs stepping over, then don't
4123 resume any threads - have it step over the breakpoint with all
4124 other threads stopped, then resume all threads again. Make sure
4125 to queue any signals that would otherwise be delivered or
4127 if (!any_pending
&& supports_breakpoints ())
4129 = (struct thread_info
*) find_inferior (&all_threads
,
4130 need_step_over_p
, NULL
);
4132 leave_all_stopped
= (need_step_over
!= NULL
|| any_pending
);
4136 if (need_step_over
!= NULL
)
4137 debug_printf ("Not resuming all, need step over\n");
4138 else if (any_pending
)
4139 debug_printf ("Not resuming, all-stop and found "
4140 "an LWP with pending status\n");
4142 debug_printf ("Resuming, no pending status or step over needed\n");
4145 /* Even if we're leaving threads stopped, queue all signals we'd
4146 otherwise deliver. */
4147 find_inferior (&all_threads
, linux_resume_one_thread
, &leave_all_stopped
);
4150 start_step_over (get_thread_lwp (need_step_over
));
4154 debug_printf ("linux_resume done\n");
4159 /* This function is called once per thread. We check the thread's
4160 last resume request, which will tell us whether to resume, step, or
4161 leave the thread stopped. Any signal the client requested to be
4162 delivered has already been enqueued at this point.
4164 If any thread that GDB wants running is stopped at an internal
4165 breakpoint that needs stepping over, we start a step-over operation
4166 on that particular thread, and leave all others stopped. */
4169 proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
4171 struct thread_info
*thread
= (struct thread_info
*) entry
;
4172 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4179 debug_printf ("proceed_one_lwp: lwp %ld\n", lwpid_of (thread
));
4184 debug_printf (" LWP %ld already running\n", lwpid_of (thread
));
4188 if (thread
->last_resume_kind
== resume_stop
4189 && thread
->last_status
.kind
!= TARGET_WAITKIND_IGNORE
)
4192 debug_printf (" client wants LWP to remain %ld stopped\n",
4197 if (lwp
->status_pending_p
)
4200 debug_printf (" LWP %ld has pending status, leaving stopped\n",
4205 gdb_assert (lwp
->suspended
>= 0);
4210 debug_printf (" LWP %ld is suspended\n", lwpid_of (thread
));
4214 if (thread
->last_resume_kind
== resume_stop
4215 && lwp
->pending_signals_to_report
== NULL
4216 && lwp
->collecting_fast_tracepoint
== 0)
4218 /* We haven't reported this LWP as stopped yet (otherwise, the
4219 last_status.kind check above would catch it, and we wouldn't
4220 reach here. This LWP may have been momentarily paused by a
4221 stop_all_lwps call while handling for example, another LWP's
4222 step-over. In that case, the pending expected SIGSTOP signal
4223 that was queued at vCont;t handling time will have already
4224 been consumed by wait_for_sigstop, and so we need to requeue
4225 another one here. Note that if the LWP already has a SIGSTOP
4226 pending, this is a no-op. */
4229 debug_printf ("Client wants LWP %ld to stop. "
4230 "Making sure it has a SIGSTOP pending\n",
4236 step
= thread
->last_resume_kind
== resume_step
;
4237 linux_resume_one_lwp (lwp
, step
, 0, NULL
);
4242 unsuspend_and_proceed_one_lwp (struct inferior_list_entry
*entry
, void *except
)
4244 struct thread_info
*thread
= (struct thread_info
*) entry
;
4245 struct lwp_info
*lwp
= get_thread_lwp (thread
);
4251 gdb_assert (lwp
->suspended
>= 0);
4253 return proceed_one_lwp (entry
, except
);
4256 /* When we finish a step-over, set threads running again. If there's
4257 another thread that may need a step-over, now's the time to start
4258 it. Eventually, we'll move all threads past their breakpoints. */
4261 proceed_all_lwps (void)
4263 struct thread_info
*need_step_over
;
4265 /* If there is a thread which would otherwise be resumed, which is
4266 stopped at a breakpoint that needs stepping over, then don't
4267 resume any threads - have it step over the breakpoint with all
4268 other threads stopped, then resume all threads again. */
4270 if (supports_breakpoints ())
4273 = (struct thread_info
*) find_inferior (&all_threads
,
4274 need_step_over_p
, NULL
);
4276 if (need_step_over
!= NULL
)
4279 debug_printf ("proceed_all_lwps: found "
4280 "thread %ld needing a step-over\n",
4281 lwpid_of (need_step_over
));
4283 start_step_over (get_thread_lwp (need_step_over
));
4289 debug_printf ("Proceeding, no step-over needed\n");
4291 find_inferior (&all_threads
, proceed_one_lwp
, NULL
);
4294 /* Stopped LWPs that the client wanted to be running, that don't have
4295 pending statuses, are set to run again, except for EXCEPT, if not
4296 NULL. This undoes a stop_all_lwps call. */
4299 unstop_all_lwps (int unsuspend
, struct lwp_info
*except
)
4305 debug_printf ("unstopping all lwps, except=(LWP %ld)\n",
4306 lwpid_of (get_lwp_thread (except
)));
4308 debug_printf ("unstopping all lwps\n");
4312 find_inferior (&all_threads
, unsuspend_and_proceed_one_lwp
, except
);
4314 find_inferior (&all_threads
, proceed_one_lwp
, except
);
4318 debug_printf ("unstop_all_lwps done\n");
4324 #ifdef HAVE_LINUX_REGSETS
4326 #define use_linux_regsets 1
4328 /* Returns true if REGSET has been disabled. */
4331 regset_disabled (struct regsets_info
*info
, struct regset_info
*regset
)
4333 return (info
->disabled_regsets
!= NULL
4334 && info
->disabled_regsets
[regset
- info
->regsets
]);
4337 /* Disable REGSET. */
4340 disable_regset (struct regsets_info
*info
, struct regset_info
*regset
)
4344 dr_offset
= regset
- info
->regsets
;
4345 if (info
->disabled_regsets
== NULL
)
4346 info
->disabled_regsets
= xcalloc (1, info
->num_regsets
);
4347 info
->disabled_regsets
[dr_offset
] = 1;
4351 regsets_fetch_inferior_registers (struct regsets_info
*regsets_info
,
4352 struct regcache
*regcache
)
4354 struct regset_info
*regset
;
4355 int saw_general_regs
= 0;
4359 pid
= lwpid_of (current_thread
);
4360 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
4365 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
))
4368 buf
= xmalloc (regset
->size
);
4370 nt_type
= regset
->nt_type
;
4374 iov
.iov_len
= regset
->size
;
4375 data
= (void *) &iov
;
4381 res
= ptrace (regset
->get_request
, pid
,
4382 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
4384 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
4390 /* If we get EIO on a regset, do not try it again for
4391 this process mode. */
4392 disable_regset (regsets_info
, regset
);
4394 else if (errno
== ENODATA
)
4396 /* ENODATA may be returned if the regset is currently
4397 not "active". This can happen in normal operation,
4398 so suppress the warning in this case. */
4403 sprintf (s
, "ptrace(regsets_fetch_inferior_registers) PID=%d",
4410 if (regset
->type
== GENERAL_REGS
)
4411 saw_general_regs
= 1;
4412 regset
->store_function (regcache
, buf
);
4416 if (saw_general_regs
)
4423 regsets_store_inferior_registers (struct regsets_info
*regsets_info
,
4424 struct regcache
*regcache
)
4426 struct regset_info
*regset
;
4427 int saw_general_regs
= 0;
4431 pid
= lwpid_of (current_thread
);
4432 for (regset
= regsets_info
->regsets
; regset
->size
>= 0; regset
++)
4437 if (regset
->size
== 0 || regset_disabled (regsets_info
, regset
)
4438 || regset
->fill_function
== NULL
)
4441 buf
= xmalloc (regset
->size
);
4443 /* First fill the buffer with the current register set contents,
4444 in case there are any items in the kernel's regset that are
4445 not in gdbserver's regcache. */
4447 nt_type
= regset
->nt_type
;
4451 iov
.iov_len
= regset
->size
;
4452 data
= (void *) &iov
;
4458 res
= ptrace (regset
->get_request
, pid
,
4459 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
4461 res
= ptrace (regset
->get_request
, pid
, data
, nt_type
);
4466 /* Then overlay our cached registers on that. */
4467 regset
->fill_function (regcache
, buf
);
4469 /* Only now do we write the register set. */
4471 res
= ptrace (regset
->set_request
, pid
,
4472 (PTRACE_TYPE_ARG3
) (long) nt_type
, data
);
4474 res
= ptrace (regset
->set_request
, pid
, data
, nt_type
);
4482 /* If we get EIO on a regset, do not try it again for
4483 this process mode. */
4484 disable_regset (regsets_info
, regset
);
4486 else if (errno
== ESRCH
)
4488 /* At this point, ESRCH should mean the process is
4489 already gone, in which case we simply ignore attempts
4490 to change its registers. See also the related
4491 comment in linux_resume_one_lwp. */
4497 perror ("Warning: ptrace(regsets_store_inferior_registers)");
4500 else if (regset
->type
== GENERAL_REGS
)
4501 saw_general_regs
= 1;
4504 if (saw_general_regs
)
4510 #else /* !HAVE_LINUX_REGSETS */
4512 #define use_linux_regsets 0
4513 #define regsets_fetch_inferior_registers(regsets_info, regcache) 1
4514 #define regsets_store_inferior_registers(regsets_info, regcache) 1
4518 /* Return 1 if register REGNO is supported by one of the regset ptrace
4519 calls or 0 if it has to be transferred individually. */
4522 linux_register_in_regsets (const struct regs_info
*regs_info
, int regno
)
4524 unsigned char mask
= 1 << (regno
% 8);
4525 size_t index
= regno
/ 8;
4527 return (use_linux_regsets
4528 && (regs_info
->regset_bitmap
== NULL
4529 || (regs_info
->regset_bitmap
[index
] & mask
) != 0));
4532 #ifdef HAVE_LINUX_USRREGS
4535 register_addr (const struct usrregs_info
*usrregs
, int regnum
)
4539 if (regnum
< 0 || regnum
>= usrregs
->num_regs
)
4540 error ("Invalid register number %d.", regnum
);
4542 addr
= usrregs
->regmap
[regnum
];
4547 /* Fetch one register. */
4549 fetch_register (const struct usrregs_info
*usrregs
,
4550 struct regcache
*regcache
, int regno
)
4557 if (regno
>= usrregs
->num_regs
)
4559 if ((*the_low_target
.cannot_fetch_register
) (regno
))
4562 regaddr
= register_addr (usrregs
, regno
);
4566 size
= ((register_size (regcache
->tdesc
, regno
)
4567 + sizeof (PTRACE_XFER_TYPE
) - 1)
4568 & -sizeof (PTRACE_XFER_TYPE
));
4569 buf
= alloca (size
);
4571 pid
= lwpid_of (current_thread
);
4572 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
4575 *(PTRACE_XFER_TYPE
*) (buf
+ i
) =
4576 ptrace (PTRACE_PEEKUSER
, pid
,
4577 /* Coerce to a uintptr_t first to avoid potential gcc warning
4578 of coercing an 8 byte integer to a 4 byte pointer. */
4579 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
, (PTRACE_TYPE_ARG4
) 0);
4580 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
4582 error ("reading register %d: %s", regno
, strerror (errno
));
4585 if (the_low_target
.supply_ptrace_register
)
4586 the_low_target
.supply_ptrace_register (regcache
, regno
, buf
);
4588 supply_register (regcache
, regno
, buf
);
4591 /* Store one register. */
4593 store_register (const struct usrregs_info
*usrregs
,
4594 struct regcache
*regcache
, int regno
)
4601 if (regno
>= usrregs
->num_regs
)
4603 if ((*the_low_target
.cannot_store_register
) (regno
))
4606 regaddr
= register_addr (usrregs
, regno
);
4610 size
= ((register_size (regcache
->tdesc
, regno
)
4611 + sizeof (PTRACE_XFER_TYPE
) - 1)
4612 & -sizeof (PTRACE_XFER_TYPE
));
4613 buf
= alloca (size
);
4614 memset (buf
, 0, size
);
4616 if (the_low_target
.collect_ptrace_register
)
4617 the_low_target
.collect_ptrace_register (regcache
, regno
, buf
);
4619 collect_register (regcache
, regno
, buf
);
4621 pid
= lwpid_of (current_thread
);
4622 for (i
= 0; i
< size
; i
+= sizeof (PTRACE_XFER_TYPE
))
4625 ptrace (PTRACE_POKEUSER
, pid
,
4626 /* Coerce to a uintptr_t first to avoid potential gcc warning
4627 about coercing an 8 byte integer to a 4 byte pointer. */
4628 (PTRACE_TYPE_ARG3
) (uintptr_t) regaddr
,
4629 (PTRACE_TYPE_ARG4
) *(PTRACE_XFER_TYPE
*) (buf
+ i
));
4632 /* At this point, ESRCH should mean the process is
4633 already gone, in which case we simply ignore attempts
4634 to change its registers. See also the related
4635 comment in linux_resume_one_lwp. */
4639 if ((*the_low_target
.cannot_store_register
) (regno
) == 0)
4640 error ("writing register %d: %s", regno
, strerror (errno
));
4642 regaddr
+= sizeof (PTRACE_XFER_TYPE
);
4646 /* Fetch all registers, or just one, from the child process.
4647 If REGNO is -1, do this for all registers, skipping any that are
4648 assumed to have been retrieved by regsets_fetch_inferior_registers,
4649 unless ALL is non-zero.
4650 Otherwise, REGNO specifies which register (so we can save time). */
4652 usr_fetch_inferior_registers (const struct regs_info
*regs_info
,
4653 struct regcache
*regcache
, int regno
, int all
)
4655 struct usrregs_info
*usr
= regs_info
->usrregs
;
4659 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
4660 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
4661 fetch_register (usr
, regcache
, regno
);
4664 fetch_register (usr
, regcache
, regno
);
4667 /* Store our register values back into the inferior.
4668 If REGNO is -1, do this for all registers, skipping any that are
4669 assumed to have been saved by regsets_store_inferior_registers,
4670 unless ALL is non-zero.
4671 Otherwise, REGNO specifies which register (so we can save time). */
4673 usr_store_inferior_registers (const struct regs_info
*regs_info
,
4674 struct regcache
*regcache
, int regno
, int all
)
4676 struct usrregs_info
*usr
= regs_info
->usrregs
;
4680 for (regno
= 0; regno
< usr
->num_regs
; regno
++)
4681 if (all
|| !linux_register_in_regsets (regs_info
, regno
))
4682 store_register (usr
, regcache
, regno
);
4685 store_register (usr
, regcache
, regno
);
4688 #else /* !HAVE_LINUX_USRREGS */
4690 #define usr_fetch_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
4691 #define usr_store_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
4697 linux_fetch_registers (struct regcache
*regcache
, int regno
)
4701 const struct regs_info
*regs_info
= (*the_low_target
.regs_info
) ();
4705 if (the_low_target
.fetch_register
!= NULL
4706 && regs_info
->usrregs
!= NULL
)
4707 for (regno
= 0; regno
< regs_info
->usrregs
->num_regs
; regno
++)
4708 (*the_low_target
.fetch_register
) (regcache
, regno
);
4710 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
, regcache
);
4711 if (regs_info
->usrregs
!= NULL
)
4712 usr_fetch_inferior_registers (regs_info
, regcache
, -1, all
);
4716 if (the_low_target
.fetch_register
!= NULL
4717 && (*the_low_target
.fetch_register
) (regcache
, regno
))
4720 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
4722 all
= regsets_fetch_inferior_registers (regs_info
->regsets_info
,
4724 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
4725 usr_fetch_inferior_registers (regs_info
, regcache
, regno
, 1);
4730 linux_store_registers (struct regcache
*regcache
, int regno
)
4734 const struct regs_info
*regs_info
= (*the_low_target
.regs_info
) ();
4738 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
4740 if (regs_info
->usrregs
!= NULL
)
4741 usr_store_inferior_registers (regs_info
, regcache
, regno
, all
);
4745 use_regsets
= linux_register_in_regsets (regs_info
, regno
);
4747 all
= regsets_store_inferior_registers (regs_info
->regsets_info
,
4749 if ((!use_regsets
|| all
) && regs_info
->usrregs
!= NULL
)
4750 usr_store_inferior_registers (regs_info
, regcache
, regno
, 1);
4755 /* Copy LEN bytes from inferior's memory starting at MEMADDR
4756 to debugger memory starting at MYADDR. */
4759 linux_read_memory (CORE_ADDR memaddr
, unsigned char *myaddr
, int len
)
4761 int pid
= lwpid_of (current_thread
);
4762 register PTRACE_XFER_TYPE
*buffer
;
4763 register CORE_ADDR addr
;
4770 /* Try using /proc. Don't bother for one word. */
4771 if (len
>= 3 * sizeof (long))
4775 /* We could keep this file open and cache it - possibly one per
4776 thread. That requires some juggling, but is even faster. */
4777 sprintf (filename
, "/proc/%d/mem", pid
);
4778 fd
= open (filename
, O_RDONLY
| O_LARGEFILE
);
4782 /* If pread64 is available, use it. It's faster if the kernel
4783 supports it (only one syscall), and it's 64-bit safe even on
4784 32-bit platforms (for instance, SPARC debugging a SPARC64
4787 bytes
= pread64 (fd
, myaddr
, len
, memaddr
);
4790 if (lseek (fd
, memaddr
, SEEK_SET
) != -1)
4791 bytes
= read (fd
, myaddr
, len
);
4798 /* Some data was read, we'll try to get the rest with ptrace. */
4808 /* Round starting address down to longword boundary. */
4809 addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
4810 /* Round ending address up; get number of longwords that makes. */
4811 count
= ((((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
4812 / sizeof (PTRACE_XFER_TYPE
));
4813 /* Allocate buffer of that many longwords. */
4814 buffer
= (PTRACE_XFER_TYPE
*) alloca (count
* sizeof (PTRACE_XFER_TYPE
));
4816 /* Read all the longwords */
4818 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
4820 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
4821 about coercing an 8 byte integer to a 4 byte pointer. */
4822 buffer
[i
] = ptrace (PTRACE_PEEKTEXT
, pid
,
4823 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
4824 (PTRACE_TYPE_ARG4
) 0);
4830 /* Copy appropriate bytes out of the buffer. */
4833 i
*= sizeof (PTRACE_XFER_TYPE
);
4834 i
-= memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1);
4836 (char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
4843 /* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
4844 memory at MEMADDR. On failure (cannot write to the inferior)
4845 returns the value of errno. Always succeeds if LEN is zero. */
4848 linux_write_memory (CORE_ADDR memaddr
, const unsigned char *myaddr
, int len
)
4851 /* Round starting address down to longword boundary. */
4852 register CORE_ADDR addr
= memaddr
& -(CORE_ADDR
) sizeof (PTRACE_XFER_TYPE
);
4853 /* Round ending address up; get number of longwords that makes. */
4855 = (((memaddr
+ len
) - addr
) + sizeof (PTRACE_XFER_TYPE
) - 1)
4856 / sizeof (PTRACE_XFER_TYPE
);
4858 /* Allocate buffer of that many longwords. */
4859 register PTRACE_XFER_TYPE
*buffer
= (PTRACE_XFER_TYPE
*)
4860 alloca (count
* sizeof (PTRACE_XFER_TYPE
));
4862 int pid
= lwpid_of (current_thread
);
4866 /* Zero length write always succeeds. */
4872 /* Dump up to four bytes. */
4873 unsigned int val
= * (unsigned int *) myaddr
;
4879 val
= val
& 0xffffff;
4880 debug_printf ("Writing %0*x to 0x%08lx\n", 2 * ((len
< 4) ? len
: 4),
4881 val
, (long)memaddr
);
4884 /* Fill start and end extra bytes of buffer with existing memory data. */
4887 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
4888 about coercing an 8 byte integer to a 4 byte pointer. */
4889 buffer
[0] = ptrace (PTRACE_PEEKTEXT
, pid
,
4890 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
4891 (PTRACE_TYPE_ARG4
) 0);
4899 = ptrace (PTRACE_PEEKTEXT
, pid
,
4900 /* Coerce to a uintptr_t first to avoid potential gcc warning
4901 about coercing an 8 byte integer to a 4 byte pointer. */
4902 (PTRACE_TYPE_ARG3
) (uintptr_t) (addr
+ (count
- 1)
4903 * sizeof (PTRACE_XFER_TYPE
)),
4904 (PTRACE_TYPE_ARG4
) 0);
4909 /* Copy data to be written over corresponding part of buffer. */
4911 memcpy ((char *) buffer
+ (memaddr
& (sizeof (PTRACE_XFER_TYPE
) - 1)),
4914 /* Write the entire buffer. */
4916 for (i
= 0; i
< count
; i
++, addr
+= sizeof (PTRACE_XFER_TYPE
))
4919 ptrace (PTRACE_POKETEXT
, pid
,
4920 /* Coerce to a uintptr_t first to avoid potential gcc warning
4921 about coercing an 8 byte integer to a 4 byte pointer. */
4922 (PTRACE_TYPE_ARG3
) (uintptr_t) addr
,
4923 (PTRACE_TYPE_ARG4
) buffer
[i
]);
4932 linux_look_up_symbols (void)
4934 #ifdef USE_THREAD_DB
4935 struct process_info
*proc
= current_process ();
4937 if (proc
->priv
->thread_db
!= NULL
)
4940 /* If the kernel supports tracing clones, then we don't need to
4941 use the magic thread event breakpoint to learn about
4943 thread_db_init (!linux_supports_traceclone ());
4948 linux_request_interrupt (void)
4950 extern unsigned long signal_pid
;
4952 /* Send a SIGINT to the process group. This acts just like the user
4953 typed a ^C on the controlling terminal. */
4954 kill (-signal_pid
, SIGINT
);
4957 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
4958 to debugger memory starting at MYADDR. */
4961 linux_read_auxv (CORE_ADDR offset
, unsigned char *myaddr
, unsigned int len
)
4963 char filename
[PATH_MAX
];
4965 int pid
= lwpid_of (current_thread
);
4967 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
4969 fd
= open (filename
, O_RDONLY
);
4973 if (offset
!= (CORE_ADDR
) 0
4974 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
4977 n
= read (fd
, myaddr
, len
);
4984 /* These breakpoint and watchpoint related wrapper functions simply
4985 pass on the function call if the target has registered a
4986 corresponding function. */
4989 linux_supports_z_point_type (char z_type
)
4991 return (the_low_target
.supports_z_point_type
!= NULL
4992 && the_low_target
.supports_z_point_type (z_type
));
4996 linux_insert_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
4997 int size
, struct raw_breakpoint
*bp
)
4999 if (the_low_target
.insert_point
!= NULL
)
5000 return the_low_target
.insert_point (type
, addr
, size
, bp
);
5002 /* Unsupported (see target.h). */
5007 linux_remove_point (enum raw_bkpt_type type
, CORE_ADDR addr
,
5008 int size
, struct raw_breakpoint
*bp
)
5010 if (the_low_target
.remove_point
!= NULL
)
5011 return the_low_target
.remove_point (type
, addr
, size
, bp
);
5013 /* Unsupported (see target.h). */
5017 /* Implement the to_stopped_by_sw_breakpoint target_ops
5021 linux_stopped_by_sw_breakpoint (void)
5023 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5025 return (lwp
->stop_reason
== TARGET_STOPPED_BY_SW_BREAKPOINT
);
5028 /* Implement the to_supports_stopped_by_sw_breakpoint target_ops
5032 linux_supports_stopped_by_sw_breakpoint (void)
5034 return USE_SIGTRAP_SIGINFO
;
5037 /* Implement the to_stopped_by_hw_breakpoint target_ops
5041 linux_stopped_by_hw_breakpoint (void)
5043 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5045 return (lwp
->stop_reason
== TARGET_STOPPED_BY_HW_BREAKPOINT
);
5048 /* Implement the to_supports_stopped_by_hw_breakpoint target_ops
5052 linux_supports_stopped_by_hw_breakpoint (void)
5054 return USE_SIGTRAP_SIGINFO
;
5058 linux_stopped_by_watchpoint (void)
5060 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5062 return lwp
->stop_reason
== TARGET_STOPPED_BY_WATCHPOINT
;
5066 linux_stopped_data_address (void)
5068 struct lwp_info
*lwp
= get_thread_lwp (current_thread
);
5070 return lwp
->stopped_data_address
;
5073 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
5074 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
5075 && defined(PT_TEXT_END_ADDR)
5077 /* This is only used for targets that define PT_TEXT_ADDR,
5078 PT_DATA_ADDR and PT_TEXT_END_ADDR. If those are not defined, supposedly
5079 the target has different ways of acquiring this information, like
5082 /* Under uClinux, programs are loaded at non-zero offsets, which we need
5083 to tell gdb about. */
5086 linux_read_offsets (CORE_ADDR
*text_p
, CORE_ADDR
*data_p
)
5088 unsigned long text
, text_end
, data
;
5089 int pid
= lwpid_of (get_thread_lwp (current_thread
));
5093 text
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_ADDR
,
5094 (PTRACE_TYPE_ARG4
) 0);
5095 text_end
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_TEXT_END_ADDR
,
5096 (PTRACE_TYPE_ARG4
) 0);
5097 data
= ptrace (PTRACE_PEEKUSER
, pid
, (PTRACE_TYPE_ARG3
) PT_DATA_ADDR
,
5098 (PTRACE_TYPE_ARG4
) 0);
5102 /* Both text and data offsets produced at compile-time (and so
5103 used by gdb) are relative to the beginning of the program,
5104 with the data segment immediately following the text segment.
5105 However, the actual runtime layout in memory may put the data
5106 somewhere else, so when we send gdb a data base-address, we
5107 use the real data base address and subtract the compile-time
5108 data base-address from it (which is just the length of the
5109 text segment). BSS immediately follows data in both
5112 *data_p
= data
- (text_end
- text
);
5121 linux_qxfer_osdata (const char *annex
,
5122 unsigned char *readbuf
, unsigned const char *writebuf
,
5123 CORE_ADDR offset
, int len
)
5125 return linux_common_xfer_osdata (annex
, readbuf
, offset
, len
);
5128 /* Convert a native/host siginfo object, into/from the siginfo in the
5129 layout of the inferiors' architecture. */
5132 siginfo_fixup (siginfo_t
*siginfo
, void *inf_siginfo
, int direction
)
5136 if (the_low_target
.siginfo_fixup
!= NULL
)
5137 done
= the_low_target
.siginfo_fixup (siginfo
, inf_siginfo
, direction
);
5139 /* If there was no callback, or the callback didn't do anything,
5140 then just do a straight memcpy. */
5144 memcpy (siginfo
, inf_siginfo
, sizeof (siginfo_t
));
5146 memcpy (inf_siginfo
, siginfo
, sizeof (siginfo_t
));
5151 linux_xfer_siginfo (const char *annex
, unsigned char *readbuf
,
5152 unsigned const char *writebuf
, CORE_ADDR offset
, int len
)
5156 char inf_siginfo
[sizeof (siginfo_t
)];
5158 if (current_thread
== NULL
)
5161 pid
= lwpid_of (current_thread
);
5164 debug_printf ("%s siginfo for lwp %d.\n",
5165 readbuf
!= NULL
? "Reading" : "Writing",
5168 if (offset
>= sizeof (siginfo
))
5171 if (ptrace (PTRACE_GETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
5174 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
5175 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
5176 inferior with a 64-bit GDBSERVER should look the same as debugging it
5177 with a 32-bit GDBSERVER, we need to convert it. */
5178 siginfo_fixup (&siginfo
, inf_siginfo
, 0);
5180 if (offset
+ len
> sizeof (siginfo
))
5181 len
= sizeof (siginfo
) - offset
;
5183 if (readbuf
!= NULL
)
5184 memcpy (readbuf
, inf_siginfo
+ offset
, len
);
5187 memcpy (inf_siginfo
+ offset
, writebuf
, len
);
5189 /* Convert back to ptrace layout before flushing it out. */
5190 siginfo_fixup (&siginfo
, inf_siginfo
, 1);
5192 if (ptrace (PTRACE_SETSIGINFO
, pid
, (PTRACE_TYPE_ARG3
) 0, &siginfo
) != 0)
5199 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
5200 so we notice when children change state; as the handler for the
5201 sigsuspend in my_waitpid. */
5204 sigchld_handler (int signo
)
5206 int old_errno
= errno
;
5212 /* fprintf is not async-signal-safe, so call write
5214 if (write (2, "sigchld_handler\n",
5215 sizeof ("sigchld_handler\n") - 1) < 0)
5216 break; /* just ignore */
5220 if (target_is_async_p ())
5221 async_file_mark (); /* trigger a linux_wait */
5227 linux_supports_non_stop (void)
5233 linux_async (int enable
)
5235 int previous
= target_is_async_p ();
5238 debug_printf ("linux_async (%d), previous=%d\n",
5241 if (previous
!= enable
)
5244 sigemptyset (&mask
);
5245 sigaddset (&mask
, SIGCHLD
);
5247 sigprocmask (SIG_BLOCK
, &mask
, NULL
);
5251 if (pipe (linux_event_pipe
) == -1)
5253 linux_event_pipe
[0] = -1;
5254 linux_event_pipe
[1] = -1;
5255 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
5257 warning ("creating event pipe failed.");
5261 fcntl (linux_event_pipe
[0], F_SETFL
, O_NONBLOCK
);
5262 fcntl (linux_event_pipe
[1], F_SETFL
, O_NONBLOCK
);
5264 /* Register the event loop handler. */
5265 add_file_handler (linux_event_pipe
[0],
5266 handle_target_event
, NULL
);
5268 /* Always trigger a linux_wait. */
5273 delete_file_handler (linux_event_pipe
[0]);
5275 close (linux_event_pipe
[0]);
5276 close (linux_event_pipe
[1]);
5277 linux_event_pipe
[0] = -1;
5278 linux_event_pipe
[1] = -1;
5281 sigprocmask (SIG_UNBLOCK
, &mask
, NULL
);
5288 linux_start_non_stop (int nonstop
)
5290 /* Register or unregister from event-loop accordingly. */
5291 linux_async (nonstop
);
5293 if (target_is_async_p () != (nonstop
!= 0))
5300 linux_supports_multi_process (void)
5306 linux_supports_disable_randomization (void)
5308 #ifdef HAVE_PERSONALITY
5316 linux_supports_agent (void)
5322 linux_supports_range_stepping (void)
5324 if (*the_low_target
.supports_range_stepping
== NULL
)
5327 return (*the_low_target
.supports_range_stepping
) ();
5330 /* Enumerate spufs IDs for process PID. */
5332 spu_enumerate_spu_ids (long pid
, unsigned char *buf
, CORE_ADDR offset
, int len
)
5338 struct dirent
*entry
;
5340 sprintf (path
, "/proc/%ld/fd", pid
);
5341 dir
= opendir (path
);
5346 while ((entry
= readdir (dir
)) != NULL
)
5352 fd
= atoi (entry
->d_name
);
5356 sprintf (path
, "/proc/%ld/fd/%d", pid
, fd
);
5357 if (stat (path
, &st
) != 0)
5359 if (!S_ISDIR (st
.st_mode
))
5362 if (statfs (path
, &stfs
) != 0)
5364 if (stfs
.f_type
!= SPUFS_MAGIC
)
5367 if (pos
>= offset
&& pos
+ 4 <= offset
+ len
)
5369 *(unsigned int *)(buf
+ pos
- offset
) = fd
;
5379 /* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
5380 object type, using the /proc file system. */
5382 linux_qxfer_spu (const char *annex
, unsigned char *readbuf
,
5383 unsigned const char *writebuf
,
5384 CORE_ADDR offset
, int len
)
5386 long pid
= lwpid_of (current_thread
);
5391 if (!writebuf
&& !readbuf
)
5399 return spu_enumerate_spu_ids (pid
, readbuf
, offset
, len
);
5402 sprintf (buf
, "/proc/%ld/fd/%s", pid
, annex
);
5403 fd
= open (buf
, writebuf
? O_WRONLY
: O_RDONLY
);
5408 && lseek (fd
, (off_t
) offset
, SEEK_SET
) != (off_t
) offset
)
5415 ret
= write (fd
, writebuf
, (size_t) len
);
5417 ret
= read (fd
, readbuf
, (size_t) len
);
5423 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
5424 struct target_loadseg
5426 /* Core address to which the segment is mapped. */
5428 /* VMA recorded in the program header. */
5430 /* Size of this segment in memory. */
5434 # if defined PT_GETDSBT
5435 struct target_loadmap
5437 /* Protocol version number, must be zero. */
5439 /* Pointer to the DSBT table, its size, and the DSBT index. */
5440 unsigned *dsbt_table
;
5441 unsigned dsbt_size
, dsbt_index
;
5442 /* Number of segments in this map. */
5444 /* The actual memory map. */
5445 struct target_loadseg segs
[/*nsegs*/];
5447 # define LINUX_LOADMAP PT_GETDSBT
5448 # define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
5449 # define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
5451 struct target_loadmap
5453 /* Protocol version number, must be zero. */
5455 /* Number of segments in this map. */
5457 /* The actual memory map. */
5458 struct target_loadseg segs
[/*nsegs*/];
5460 # define LINUX_LOADMAP PTRACE_GETFDPIC
5461 # define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
5462 # define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
5466 linux_read_loadmap (const char *annex
, CORE_ADDR offset
,
5467 unsigned char *myaddr
, unsigned int len
)
5469 int pid
= lwpid_of (current_thread
);
5471 struct target_loadmap
*data
= NULL
;
5472 unsigned int actual_length
, copy_length
;
5474 if (strcmp (annex
, "exec") == 0)
5475 addr
= (int) LINUX_LOADMAP_EXEC
;
5476 else if (strcmp (annex
, "interp") == 0)
5477 addr
= (int) LINUX_LOADMAP_INTERP
;
5481 if (ptrace (LINUX_LOADMAP
, pid
, addr
, &data
) != 0)
5487 actual_length
= sizeof (struct target_loadmap
)
5488 + sizeof (struct target_loadseg
) * data
->nsegs
;
5490 if (offset
< 0 || offset
> actual_length
)
5493 copy_length
= actual_length
- offset
< len
? actual_length
- offset
: len
;
5494 memcpy (myaddr
, (char *) data
+ offset
, copy_length
);
5498 # define linux_read_loadmap NULL
5499 #endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
5502 linux_process_qsupported (const char *query
)
5504 if (the_low_target
.process_qsupported
!= NULL
)
5505 the_low_target
.process_qsupported (query
);
5509 linux_supports_tracepoints (void)
5511 if (*the_low_target
.supports_tracepoints
== NULL
)
5514 return (*the_low_target
.supports_tracepoints
) ();
5518 linux_read_pc (struct regcache
*regcache
)
5520 if (the_low_target
.get_pc
== NULL
)
5523 return (*the_low_target
.get_pc
) (regcache
);
5527 linux_write_pc (struct regcache
*regcache
, CORE_ADDR pc
)
5529 gdb_assert (the_low_target
.set_pc
!= NULL
);
5531 (*the_low_target
.set_pc
) (regcache
, pc
);
5535 linux_thread_stopped (struct thread_info
*thread
)
5537 return get_thread_lwp (thread
)->stopped
;
5540 /* This exposes stop-all-threads functionality to other modules. */
5543 linux_pause_all (int freeze
)
5545 stop_all_lwps (freeze
, NULL
);
5548 /* This exposes unstop-all-threads functionality to other gdbserver
5552 linux_unpause_all (int unfreeze
)
5554 unstop_all_lwps (unfreeze
, NULL
);
5558 linux_prepare_to_access_memory (void)
5560 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
5563 linux_pause_all (1);
5568 linux_done_accessing_memory (void)
5570 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
5573 linux_unpause_all (1);
5577 linux_install_fast_tracepoint_jump_pad (CORE_ADDR tpoint
, CORE_ADDR tpaddr
,
5578 CORE_ADDR collector
,
5581 CORE_ADDR
*jump_entry
,
5582 CORE_ADDR
*trampoline
,
5583 ULONGEST
*trampoline_size
,
5584 unsigned char *jjump_pad_insn
,
5585 ULONGEST
*jjump_pad_insn_size
,
5586 CORE_ADDR
*adjusted_insn_addr
,
5587 CORE_ADDR
*adjusted_insn_addr_end
,
5590 return (*the_low_target
.install_fast_tracepoint_jump_pad
)
5591 (tpoint
, tpaddr
, collector
, lockaddr
, orig_size
,
5592 jump_entry
, trampoline
, trampoline_size
,
5593 jjump_pad_insn
, jjump_pad_insn_size
,
5594 adjusted_insn_addr
, adjusted_insn_addr_end
,
5598 static struct emit_ops
*
5599 linux_emit_ops (void)
5601 if (the_low_target
.emit_ops
!= NULL
)
5602 return (*the_low_target
.emit_ops
) ();
5608 linux_get_min_fast_tracepoint_insn_len (void)
5610 return (*the_low_target
.get_min_fast_tracepoint_insn_len
) ();
5613 /* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
5616 get_phdr_phnum_from_proc_auxv (const int pid
, const int is_elf64
,
5617 CORE_ADDR
*phdr_memaddr
, int *num_phdr
)
5619 char filename
[PATH_MAX
];
5621 const int auxv_size
= is_elf64
5622 ? sizeof (Elf64_auxv_t
) : sizeof (Elf32_auxv_t
);
5623 char buf
[sizeof (Elf64_auxv_t
)]; /* The larger of the two. */
5625 xsnprintf (filename
, sizeof filename
, "/proc/%d/auxv", pid
);
5627 fd
= open (filename
, O_RDONLY
);
5633 while (read (fd
, buf
, auxv_size
) == auxv_size
5634 && (*phdr_memaddr
== 0 || *num_phdr
== 0))
5638 Elf64_auxv_t
*const aux
= (Elf64_auxv_t
*) buf
;
5640 switch (aux
->a_type
)
5643 *phdr_memaddr
= aux
->a_un
.a_val
;
5646 *num_phdr
= aux
->a_un
.a_val
;
5652 Elf32_auxv_t
*const aux
= (Elf32_auxv_t
*) buf
;
5654 switch (aux
->a_type
)
5657 *phdr_memaddr
= aux
->a_un
.a_val
;
5660 *num_phdr
= aux
->a_un
.a_val
;
5668 if (*phdr_memaddr
== 0 || *num_phdr
== 0)
5670 warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
5671 "phdr_memaddr = %ld, phdr_num = %d",
5672 (long) *phdr_memaddr
, *num_phdr
);
5679 /* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
5682 get_dynamic (const int pid
, const int is_elf64
)
5684 CORE_ADDR phdr_memaddr
, relocation
;
5686 unsigned char *phdr_buf
;
5687 const int phdr_size
= is_elf64
? sizeof (Elf64_Phdr
) : sizeof (Elf32_Phdr
);
5689 if (get_phdr_phnum_from_proc_auxv (pid
, is_elf64
, &phdr_memaddr
, &num_phdr
))
5692 gdb_assert (num_phdr
< 100); /* Basic sanity check. */
5693 phdr_buf
= alloca (num_phdr
* phdr_size
);
5695 if (linux_read_memory (phdr_memaddr
, phdr_buf
, num_phdr
* phdr_size
))
5698 /* Compute relocation: it is expected to be 0 for "regular" executables,
5699 non-zero for PIE ones. */
5701 for (i
= 0; relocation
== -1 && i
< num_phdr
; i
++)
5704 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5706 if (p
->p_type
== PT_PHDR
)
5707 relocation
= phdr_memaddr
- p
->p_vaddr
;
5711 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5713 if (p
->p_type
== PT_PHDR
)
5714 relocation
= phdr_memaddr
- p
->p_vaddr
;
5717 if (relocation
== -1)
5719 /* PT_PHDR is optional, but necessary for PIE in general. Fortunately
5720 any real world executables, including PIE executables, have always
5721 PT_PHDR present. PT_PHDR is not present in some shared libraries or
5722 in fpc (Free Pascal 2.4) binaries but neither of those have a need for
5723 or present DT_DEBUG anyway (fpc binaries are statically linked).
5725 Therefore if there exists DT_DEBUG there is always also PT_PHDR.
5727 GDB could find RELOCATION also from AT_ENTRY - e_entry. */
5732 for (i
= 0; i
< num_phdr
; i
++)
5736 Elf64_Phdr
*const p
= (Elf64_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5738 if (p
->p_type
== PT_DYNAMIC
)
5739 return p
->p_vaddr
+ relocation
;
5743 Elf32_Phdr
*const p
= (Elf32_Phdr
*) (phdr_buf
+ i
* phdr_size
);
5745 if (p
->p_type
== PT_DYNAMIC
)
5746 return p
->p_vaddr
+ relocation
;
5753 /* Return &_r_debug in the inferior, or -1 if not present. Return value
5754 can be 0 if the inferior does not yet have the library list initialized.
5755 We look for DT_MIPS_RLD_MAP first. MIPS executables use this instead of
5756 DT_DEBUG, although they sometimes contain an unused DT_DEBUG entry too. */
5759 get_r_debug (const int pid
, const int is_elf64
)
5761 CORE_ADDR dynamic_memaddr
;
5762 const int dyn_size
= is_elf64
? sizeof (Elf64_Dyn
) : sizeof (Elf32_Dyn
);
5763 unsigned char buf
[sizeof (Elf64_Dyn
)]; /* The larger of the two. */
5766 dynamic_memaddr
= get_dynamic (pid
, is_elf64
);
5767 if (dynamic_memaddr
== 0)
5770 while (linux_read_memory (dynamic_memaddr
, buf
, dyn_size
) == 0)
5774 Elf64_Dyn
*const dyn
= (Elf64_Dyn
*) buf
;
5775 #ifdef DT_MIPS_RLD_MAP
5779 unsigned char buf
[sizeof (Elf64_Xword
)];
5783 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
5785 if (linux_read_memory (dyn
->d_un
.d_val
,
5786 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
5791 #endif /* DT_MIPS_RLD_MAP */
5793 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
5794 map
= dyn
->d_un
.d_val
;
5796 if (dyn
->d_tag
== DT_NULL
)
5801 Elf32_Dyn
*const dyn
= (Elf32_Dyn
*) buf
;
5802 #ifdef DT_MIPS_RLD_MAP
5806 unsigned char buf
[sizeof (Elf32_Word
)];
5810 if (dyn
->d_tag
== DT_MIPS_RLD_MAP
)
5812 if (linux_read_memory (dyn
->d_un
.d_val
,
5813 rld_map
.buf
, sizeof (rld_map
.buf
)) == 0)
5818 #endif /* DT_MIPS_RLD_MAP */
5820 if (dyn
->d_tag
== DT_DEBUG
&& map
== -1)
5821 map
= dyn
->d_un
.d_val
;
5823 if (dyn
->d_tag
== DT_NULL
)
5827 dynamic_memaddr
+= dyn_size
;
5833 /* Read one pointer from MEMADDR in the inferior. */
5836 read_one_ptr (CORE_ADDR memaddr
, CORE_ADDR
*ptr
, int ptr_size
)
5840 /* Go through a union so this works on either big or little endian
5841 hosts, when the inferior's pointer size is smaller than the size
5842 of CORE_ADDR. It is assumed the inferior's endianness is the
5843 same of the superior's. */
5846 CORE_ADDR core_addr
;
5851 ret
= linux_read_memory (memaddr
, &addr
.uc
, ptr_size
);
5854 if (ptr_size
== sizeof (CORE_ADDR
))
5855 *ptr
= addr
.core_addr
;
5856 else if (ptr_size
== sizeof (unsigned int))
5859 gdb_assert_not_reached ("unhandled pointer size");
5864 struct link_map_offsets
5866 /* Offset and size of r_debug.r_version. */
5867 int r_version_offset
;
5869 /* Offset and size of r_debug.r_map. */
5872 /* Offset to l_addr field in struct link_map. */
5875 /* Offset to l_name field in struct link_map. */
5878 /* Offset to l_ld field in struct link_map. */
5881 /* Offset to l_next field in struct link_map. */
5884 /* Offset to l_prev field in struct link_map. */
5888 /* Construct qXfer:libraries-svr4:read reply. */
5891 linux_qxfer_libraries_svr4 (const char *annex
, unsigned char *readbuf
,
5892 unsigned const char *writebuf
,
5893 CORE_ADDR offset
, int len
)
5896 unsigned document_len
;
5897 struct process_info_private
*const priv
= current_process ()->priv
;
5898 char filename
[PATH_MAX
];
5901 static const struct link_map_offsets lmo_32bit_offsets
=
5903 0, /* r_version offset. */
5904 4, /* r_debug.r_map offset. */
5905 0, /* l_addr offset in link_map. */
5906 4, /* l_name offset in link_map. */
5907 8, /* l_ld offset in link_map. */
5908 12, /* l_next offset in link_map. */
5909 16 /* l_prev offset in link_map. */
5912 static const struct link_map_offsets lmo_64bit_offsets
=
5914 0, /* r_version offset. */
5915 8, /* r_debug.r_map offset. */
5916 0, /* l_addr offset in link_map. */
5917 8, /* l_name offset in link_map. */
5918 16, /* l_ld offset in link_map. */
5919 24, /* l_next offset in link_map. */
5920 32 /* l_prev offset in link_map. */
5922 const struct link_map_offsets
*lmo
;
5923 unsigned int machine
;
5925 CORE_ADDR lm_addr
= 0, lm_prev
= 0;
5926 int allocated
= 1024;
5928 CORE_ADDR l_name
, l_addr
, l_ld
, l_next
, l_prev
;
5929 int header_done
= 0;
5931 if (writebuf
!= NULL
)
5933 if (readbuf
== NULL
)
5936 pid
= lwpid_of (current_thread
);
5937 xsnprintf (filename
, sizeof filename
, "/proc/%d/exe", pid
);
5938 is_elf64
= elf_64_file_p (filename
, &machine
);
5939 lmo
= is_elf64
? &lmo_64bit_offsets
: &lmo_32bit_offsets
;
5940 ptr_size
= is_elf64
? 8 : 4;
5942 while (annex
[0] != '\0')
5948 sep
= strchr (annex
, '=');
5953 if (len
== 5 && startswith (annex
, "start"))
5955 else if (len
== 4 && startswith (annex
, "prev"))
5959 annex
= strchr (sep
, ';');
5966 annex
= decode_address_to_semicolon (addrp
, sep
+ 1);
5973 if (priv
->r_debug
== 0)
5974 priv
->r_debug
= get_r_debug (pid
, is_elf64
);
5976 /* We failed to find DT_DEBUG. Such situation will not change
5977 for this inferior - do not retry it. Report it to GDB as
5978 E01, see for the reasons at the GDB solib-svr4.c side. */
5979 if (priv
->r_debug
== (CORE_ADDR
) -1)
5982 if (priv
->r_debug
!= 0)
5984 if (linux_read_memory (priv
->r_debug
+ lmo
->r_version_offset
,
5985 (unsigned char *) &r_version
,
5986 sizeof (r_version
)) != 0
5989 warning ("unexpected r_debug version %d", r_version
);
5991 else if (read_one_ptr (priv
->r_debug
+ lmo
->r_map_offset
,
5992 &lm_addr
, ptr_size
) != 0)
5994 warning ("unable to read r_map from 0x%lx",
5995 (long) priv
->r_debug
+ lmo
->r_map_offset
);
6000 document
= xmalloc (allocated
);
6001 strcpy (document
, "<library-list-svr4 version=\"1.0\"");
6002 p
= document
+ strlen (document
);
6005 && read_one_ptr (lm_addr
+ lmo
->l_name_offset
,
6006 &l_name
, ptr_size
) == 0
6007 && read_one_ptr (lm_addr
+ lmo
->l_addr_offset
,
6008 &l_addr
, ptr_size
) == 0
6009 && read_one_ptr (lm_addr
+ lmo
->l_ld_offset
,
6010 &l_ld
, ptr_size
) == 0
6011 && read_one_ptr (lm_addr
+ lmo
->l_prev_offset
,
6012 &l_prev
, ptr_size
) == 0
6013 && read_one_ptr (lm_addr
+ lmo
->l_next_offset
,
6014 &l_next
, ptr_size
) == 0)
6016 unsigned char libname
[PATH_MAX
];
6018 if (lm_prev
!= l_prev
)
6020 warning ("Corrupted shared library list: 0x%lx != 0x%lx",
6021 (long) lm_prev
, (long) l_prev
);
6025 /* Ignore the first entry even if it has valid name as the first entry
6026 corresponds to the main executable. The first entry should not be
6027 skipped if the dynamic loader was loaded late by a static executable
6028 (see solib-svr4.c parameter ignore_first). But in such case the main
6029 executable does not have PT_DYNAMIC present and this function already
6030 exited above due to failed get_r_debug. */
6033 sprintf (p
, " main-lm=\"0x%lx\"", (unsigned long) lm_addr
);
6038 /* Not checking for error because reading may stop before
6039 we've got PATH_MAX worth of characters. */
6041 linux_read_memory (l_name
, libname
, sizeof (libname
) - 1);
6042 libname
[sizeof (libname
) - 1] = '\0';
6043 if (libname
[0] != '\0')
6045 /* 6x the size for xml_escape_text below. */
6046 size_t len
= 6 * strlen ((char *) libname
);
6051 /* Terminate `<library-list-svr4'. */
6056 while (allocated
< p
- document
+ len
+ 200)
6058 /* Expand to guarantee sufficient storage. */
6059 uintptr_t document_len
= p
- document
;
6061 document
= xrealloc (document
, 2 * allocated
);
6063 p
= document
+ document_len
;
6066 name
= xml_escape_text ((char *) libname
);
6067 p
+= sprintf (p
, "<library name=\"%s\" lm=\"0x%lx\" "
6068 "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
6069 name
, (unsigned long) lm_addr
,
6070 (unsigned long) l_addr
, (unsigned long) l_ld
);
6081 /* Empty list; terminate `<library-list-svr4'. */
6085 strcpy (p
, "</library-list-svr4>");
6087 document_len
= strlen (document
);
6088 if (offset
< document_len
)
6089 document_len
-= offset
;
6092 if (len
> document_len
)
6095 memcpy (readbuf
, document
+ offset
, len
);
6101 #ifdef HAVE_LINUX_BTRACE
6103 /* See to_enable_btrace target method. */
6105 static struct btrace_target_info
*
6106 linux_low_enable_btrace (ptid_t ptid
, const struct btrace_config
*conf
)
6108 struct btrace_target_info
*tinfo
;
6110 tinfo
= linux_enable_btrace (ptid
, conf
);
6112 if (tinfo
!= NULL
&& tinfo
->ptr_bits
== 0)
6114 struct thread_info
*thread
= find_thread_ptid (ptid
);
6115 struct regcache
*regcache
= get_thread_regcache (thread
, 0);
6117 tinfo
->ptr_bits
= register_size (regcache
->tdesc
, 0) * 8;
6123 /* See to_disable_btrace target method. */
6126 linux_low_disable_btrace (struct btrace_target_info
*tinfo
)
6128 enum btrace_error err
;
6130 err
= linux_disable_btrace (tinfo
);
6131 return (err
== BTRACE_ERR_NONE
? 0 : -1);
6134 /* See to_read_btrace target method. */
6137 linux_low_read_btrace (struct btrace_target_info
*tinfo
, struct buffer
*buffer
,
6140 struct btrace_data btrace
;
6141 struct btrace_block
*block
;
6142 enum btrace_error err
;
6145 btrace_data_init (&btrace
);
6147 err
= linux_read_btrace (&btrace
, tinfo
, type
);
6148 if (err
!= BTRACE_ERR_NONE
)
6150 if (err
== BTRACE_ERR_OVERFLOW
)
6151 buffer_grow_str0 (buffer
, "E.Overflow.");
6153 buffer_grow_str0 (buffer
, "E.Generic Error.");
6155 btrace_data_fini (&btrace
);
6159 switch (btrace
.format
)
6161 case BTRACE_FORMAT_NONE
:
6162 buffer_grow_str0 (buffer
, "E.No Trace.");
6165 case BTRACE_FORMAT_BTS
:
6166 buffer_grow_str (buffer
, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
6167 buffer_grow_str (buffer
, "<btrace version=\"1.0\">\n");
6170 VEC_iterate (btrace_block_s
, btrace
.variant
.bts
.blocks
, i
, block
);
6172 buffer_xml_printf (buffer
, "<block begin=\"0x%s\" end=\"0x%s\"/>\n",
6173 paddress (block
->begin
), paddress (block
->end
));
6175 buffer_grow_str0 (buffer
, "</btrace>\n");
6179 buffer_grow_str0 (buffer
, "E.Unknown Trace Format.");
6181 btrace_data_fini (&btrace
);
6185 btrace_data_fini (&btrace
);
6189 /* See to_btrace_conf target method. */
6192 linux_low_btrace_conf (const struct btrace_target_info
*tinfo
,
6193 struct buffer
*buffer
)
6195 const struct btrace_config
*conf
;
6197 buffer_grow_str (buffer
, "<!DOCTYPE btrace-conf SYSTEM \"btrace-conf.dtd\">\n");
6198 buffer_grow_str (buffer
, "<btrace-conf version=\"1.0\">\n");
6200 conf
= linux_btrace_conf (tinfo
);
6203 switch (conf
->format
)
6205 case BTRACE_FORMAT_NONE
:
6208 case BTRACE_FORMAT_BTS
:
6209 buffer_xml_printf (buffer
, "<bts");
6210 buffer_xml_printf (buffer
, " size=\"0x%x\"", conf
->bts
.size
);
6211 buffer_xml_printf (buffer
, " />\n");
6216 buffer_grow_str0 (buffer
, "</btrace-conf>\n");
6219 #endif /* HAVE_LINUX_BTRACE */
6221 static struct target_ops linux_target_ops
= {
6222 linux_create_inferior
,
6231 linux_fetch_registers
,
6232 linux_store_registers
,
6233 linux_prepare_to_access_memory
,
6234 linux_done_accessing_memory
,
6237 linux_look_up_symbols
,
6238 linux_request_interrupt
,
6240 linux_supports_z_point_type
,
6243 linux_stopped_by_sw_breakpoint
,
6244 linux_supports_stopped_by_sw_breakpoint
,
6245 linux_stopped_by_hw_breakpoint
,
6246 linux_supports_stopped_by_hw_breakpoint
,
6247 linux_stopped_by_watchpoint
,
6248 linux_stopped_data_address
,
6249 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
6250 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
6251 && defined(PT_TEXT_END_ADDR)
6256 #ifdef USE_THREAD_DB
6257 thread_db_get_tls_address
,
6262 hostio_last_error_from_errno
,
6265 linux_supports_non_stop
,
6267 linux_start_non_stop
,
6268 linux_supports_multi_process
,
6269 #ifdef USE_THREAD_DB
6270 thread_db_handle_monitor_command
,
6274 linux_common_core_of_thread
,
6276 linux_process_qsupported
,
6277 linux_supports_tracepoints
,
6280 linux_thread_stopped
,
6284 linux_stabilize_threads
,
6285 linux_install_fast_tracepoint_jump_pad
,
6287 linux_supports_disable_randomization
,
6288 linux_get_min_fast_tracepoint_insn_len
,
6289 linux_qxfer_libraries_svr4
,
6290 linux_supports_agent
,
6291 #ifdef HAVE_LINUX_BTRACE
6292 linux_supports_btrace
,
6293 linux_low_enable_btrace
,
6294 linux_low_disable_btrace
,
6295 linux_low_read_btrace
,
6296 linux_low_btrace_conf
,
6304 linux_supports_range_stepping
,
6308 linux_init_signals ()
6310 /* FIXME drow/2002-06-09: As above, we should check with LinuxThreads
6311 to find what the cancel signal actually is. */
6312 #ifndef __ANDROID__ /* Bionic doesn't use SIGRTMIN the way glibc does. */
6313 signal (__SIGRTMIN
+1, SIG_IGN
);
6317 #ifdef HAVE_LINUX_REGSETS
6319 initialize_regsets_info (struct regsets_info
*info
)
6321 for (info
->num_regsets
= 0;
6322 info
->regsets
[info
->num_regsets
].size
>= 0;
6323 info
->num_regsets
++)
6329 initialize_low (void)
6331 struct sigaction sigchld_action
;
6332 memset (&sigchld_action
, 0, sizeof (sigchld_action
));
6333 set_target_ops (&linux_target_ops
);
6334 set_breakpoint_data (the_low_target
.breakpoint
,
6335 the_low_target
.breakpoint_len
);
6336 linux_init_signals ();
6337 linux_ptrace_init_warnings ();
6339 sigchld_action
.sa_handler
= sigchld_handler
;
6340 sigemptyset (&sigchld_action
.sa_mask
);
6341 sigchld_action
.sa_flags
= SA_RESTART
;
6342 sigaction (SIGCHLD
, &sigchld_action
, NULL
);
6344 initialize_low_arch ();