1 /* Low level interface to ptrace, for the remote server for GDB.
2 Copyright (C) 1995-2016 Free Software Foundation, Inc.
4 This file is part of GDB.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>. */
20 #include "linux-low.h"
21 #include "nat/linux-osdata.h"
25 #include "signals-state-save-restore.h"
26 #include "nat/linux-nat.h"
27 #include "nat/linux-waitpid.h"
29 #include "nat/gdb_ptrace.h"
30 #include "nat/linux-ptrace.h"
31 #include "nat/linux-procfs.h"
32 #include "nat/linux-personality.h"
34 #include <sys/ioctl.h>
37 #include <sys/syscall.h>
41 #include <sys/types.h>
46 #include "filestuff.h"
47 #include "tracepoint.h"
51 /* Don't include <linux/elf.h> here. If it got included by gdb_proc_service.h
52 then ELFMAG0 will have been defined. If it didn't get included by
53 gdb_proc_service.h then including it will likely introduce a duplicate
54 definition of elf_fpregset_t. */
57 #include "nat/linux-namespaces.h"
60 #define SPUFS_MAGIC 0x23c9b64e
63 #ifdef HAVE_PERSONALITY
64 # include <sys/personality.h>
65 # if !HAVE_DECL_ADDR_NO_RANDOMIZE
66 # define ADDR_NO_RANDOMIZE 0x0040000
74 /* Some targets did not define these ptrace constants from the start,
75 so gdbserver defines them locally here. In the future, these may
76 be removed after they are added to asm/ptrace.h. */
77 #if !(defined(PT_TEXT_ADDR) \
78 || defined(PT_DATA_ADDR) \
79 || defined(PT_TEXT_END_ADDR))
80 #if defined(__mcoldfire__)
81 /* These are still undefined in 3.10 kernels. */
82 #define PT_TEXT_ADDR 49*4
83 #define PT_DATA_ADDR 50*4
84 #define PT_TEXT_END_ADDR 51*4
85 /* BFIN already defines these since at least 2.6.32 kernels. */
87 #define PT_TEXT_ADDR 220
88 #define PT_TEXT_END_ADDR 224
89 #define PT_DATA_ADDR 228
90 /* These are still undefined in 3.10 kernels. */
91 #elif defined(__TMS320C6X__)
92 #define PT_TEXT_ADDR (0x10000*4)
93 #define PT_DATA_ADDR (0x10004*4)
94 #define PT_TEXT_END_ADDR (0x10008*4)
98 #ifdef HAVE_LINUX_BTRACE
99 # include "nat/linux-btrace.h"
100 # include "btrace-common.h"
103 #ifndef HAVE_ELF32_AUXV_T
104 /* Copied from glibc's elf.h. */
107 uint32_t a_type; /* Entry type */
110 uint32_t a_val; /* Integer value */
111 /* We use to have pointer elements added here. We cannot do that,
112 though, since it does not work when using 32-bit definitions
113 on 64-bit platforms and vice versa. */
118 #ifndef HAVE_ELF64_AUXV_T
119 /* Copied from glibc's elf.h. */
122 uint64_t a_type; /* Entry type */
125 uint64_t a_val; /* Integer value */
126 /* We use to have pointer elements added here. We cannot do that,
127 though, since it does not work when using 32-bit definitions
128 on 64-bit platforms and vice versa. */
133 /* Does the current host support PTRACE_GETREGSET? */
134 int have_ptrace_getregset = -1;
138 /* See nat/linux-nat.h. */
141 ptid_of_lwp (struct lwp_info *lwp)
143 return ptid_of (get_lwp_thread (lwp));
146 /* See nat/linux-nat.h. */
149 lwp_set_arch_private_info (struct lwp_info *lwp,
150 struct arch_lwp_info *info)
152 lwp->arch_private = info;
155 /* See nat/linux-nat.h. */
157 struct arch_lwp_info *
158 lwp_arch_private_info (struct lwp_info *lwp)
160 return lwp->arch_private;
163 /* See nat/linux-nat.h. */
166 lwp_is_stopped (struct lwp_info *lwp)
171 /* See nat/linux-nat.h. */
173 enum target_stop_reason
174 lwp_stop_reason (struct lwp_info *lwp)
176 return lwp->stop_reason;
179 /* See nat/linux-nat.h. */
182 lwp_is_stepping (struct lwp_info *lwp)
184 return lwp->stepping;
187 /* A list of all unknown processes which receive stop signals. Some
188 other process will presumably claim each of these as forked
189 children momentarily. */
191 struct simple_pid_list
193 /* The process ID. */
196 /* The status as reported by waitpid. */
200 struct simple_pid_list *next;
202 struct simple_pid_list *stopped_pids;
204 /* Trivial list manipulation functions to keep track of a list of new
205 stopped processes. */
208 add_to_pid_list (struct simple_pid_list **listp, int pid, int status)
210 struct simple_pid_list *new_pid = XNEW (struct simple_pid_list);
213 new_pid->status = status;
214 new_pid->next = *listp;
219 pull_pid_from_list (struct simple_pid_list **listp, int pid, int *statusp)
221 struct simple_pid_list **p;
223 for (p = listp; *p != NULL; p = &(*p)->next)
224 if ((*p)->pid == pid)
226 struct simple_pid_list *next = (*p)->next;
228 *statusp = (*p)->status;
236 enum stopping_threads_kind
238 /* Not stopping threads presently. */
239 NOT_STOPPING_THREADS,
241 /* Stopping threads. */
244 /* Stopping and suspending threads. */
245 STOPPING_AND_SUSPENDING_THREADS
248 /* This is set while stop_all_lwps is in effect. */
249 enum stopping_threads_kind stopping_threads = NOT_STOPPING_THREADS;
251 /* FIXME make into a target method? */
252 int using_threads = 1;
254 /* True if we're presently stabilizing threads (moving them out of
256 static int stabilizing_threads;
258 static void linux_resume_one_lwp (struct lwp_info *lwp,
259 int step, int signal, siginfo_t *info);
260 static void linux_resume (struct thread_resume *resume_info, size_t n);
261 static void stop_all_lwps (int suspend, struct lwp_info *except);
262 static void unstop_all_lwps (int unsuspend, struct lwp_info *except);
263 static void unsuspend_all_lwps (struct lwp_info *except);
264 static int linux_wait_for_event_filtered (ptid_t wait_ptid, ptid_t filter_ptid,
265 int *wstat, int options);
266 static int linux_wait_for_event (ptid_t ptid, int *wstat, int options);
267 static struct lwp_info *add_lwp (ptid_t ptid);
268 static void linux_mourn (struct process_info *process);
269 static int linux_stopped_by_watchpoint (void);
270 static void mark_lwp_dead (struct lwp_info *lwp, int wstat);
271 static int lwp_is_marked_dead (struct lwp_info *lwp);
272 static void proceed_all_lwps (void);
273 static int finish_step_over (struct lwp_info *lwp);
274 static int kill_lwp (unsigned long lwpid, int signo);
275 static void enqueue_pending_signal (struct lwp_info *lwp, int signal, siginfo_t *info);
276 static void complete_ongoing_step_over (void);
277 static int linux_low_ptrace_options (int attached);
278 static int check_ptrace_stopped_lwp_gone (struct lwp_info *lp);
279 static int proceed_one_lwp (struct inferior_list_entry *entry, void *except);
281 /* When the event-loop is doing a step-over, this points at the thread
283 ptid_t step_over_bkpt;
285 /* True if the low target can hardware single-step. */
288 can_hardware_single_step (void)
290 if (the_low_target.supports_hardware_single_step != NULL)
291 return the_low_target.supports_hardware_single_step ();
296 /* True if the low target can software single-step. Such targets
297 implement the GET_NEXT_PCS callback. */
300 can_software_single_step (void)
302 return (the_low_target.get_next_pcs != NULL);
305 /* True if the low target supports memory breakpoints. If so, we'll
306 have a GET_PC implementation. */
309 supports_breakpoints (void)
311 return (the_low_target.get_pc != NULL);
314 /* Returns true if this target can support fast tracepoints. This
315 does not mean that the in-process agent has been loaded in the
319 supports_fast_tracepoints (void)
321 return the_low_target.install_fast_tracepoint_jump_pad != NULL;
324 /* True if LWP is stopped in its stepping range. */
327 lwp_in_step_range (struct lwp_info *lwp)
329 CORE_ADDR pc = lwp->stop_pc;
331 return (pc >= lwp->step_range_start && pc < lwp->step_range_end);
334 struct pending_signals
338 struct pending_signals *prev;
341 /* The read/write ends of the pipe registered as waitable file in the
343 static int linux_event_pipe[2] = { -1, -1 };
345 /* True if we're currently in async mode. */
346 #define target_is_async_p() (linux_event_pipe[0] != -1)
348 static void send_sigstop (struct lwp_info *lwp);
349 static void wait_for_sigstop (void);
351 /* Return non-zero if HEADER is a 64-bit ELF file. */
354 elf_64_header_p (const Elf64_Ehdr *header, unsigned int *machine)
356 if (header->e_ident[EI_MAG0] == ELFMAG0
357 && header->e_ident[EI_MAG1] == ELFMAG1
358 && header->e_ident[EI_MAG2] == ELFMAG2
359 && header->e_ident[EI_MAG3] == ELFMAG3)
361 *machine = header->e_machine;
362 return header->e_ident[EI_CLASS] == ELFCLASS64;
369 /* Return non-zero if FILE is a 64-bit ELF file,
370 zero if the file is not a 64-bit ELF file,
371 and -1 if the file is not accessible or doesn't exist. */
374 elf_64_file_p (const char *file, unsigned int *machine)
379 fd = open (file, O_RDONLY);
383 if (read (fd, &header, sizeof (header)) != sizeof (header))
390 return elf_64_header_p (&header, machine);
393 /* Accepts an integer PID; Returns true if the executable PID is
394 running is a 64-bit ELF file.. */
397 linux_pid_exe_is_elf_64_file (int pid, unsigned int *machine)
401 sprintf (file, "/proc/%d/exe", pid);
402 return elf_64_file_p (file, machine);
406 delete_lwp (struct lwp_info *lwp)
408 struct thread_info *thr = get_lwp_thread (lwp);
411 debug_printf ("deleting %ld\n", lwpid_of (thr));
414 free (lwp->arch_private);
418 /* Add a process to the common process list, and set its private
421 static struct process_info *
422 linux_add_process (int pid, int attached)
424 struct process_info *proc;
426 proc = add_process (pid, attached);
427 proc->priv = XCNEW (struct process_info_private);
429 if (the_low_target.new_process != NULL)
430 proc->priv->arch_private = the_low_target.new_process ();
435 static CORE_ADDR get_pc (struct lwp_info *lwp);
437 /* Call the target arch_setup function on the current thread. */
440 linux_arch_setup (void)
442 the_low_target.arch_setup ();
445 /* Call the target arch_setup function on THREAD. */
448 linux_arch_setup_thread (struct thread_info *thread)
450 struct thread_info *saved_thread;
452 saved_thread = current_thread;
453 current_thread = thread;
457 current_thread = saved_thread;
460 /* Handle a GNU/Linux extended wait response. If we see a clone,
461 fork, or vfork event, we need to add the new LWP to our list
462 (and return 0 so as not to report the trap to higher layers).
463 If we see an exec event, we will modify ORIG_EVENT_LWP to point
464 to a new LWP representing the new program. */
467 handle_extended_wait (struct lwp_info **orig_event_lwp, int wstat)
469 struct lwp_info *event_lwp = *orig_event_lwp;
470 int event = linux_ptrace_get_extended_event (wstat);
471 struct thread_info *event_thr = get_lwp_thread (event_lwp);
472 struct lwp_info *new_lwp;
474 gdb_assert (event_lwp->waitstatus.kind == TARGET_WAITKIND_IGNORE);
476 /* All extended events we currently use are mid-syscall. Only
477 PTRACE_EVENT_STOP is delivered more like a signal-stop, but
478 you have to be using PTRACE_SEIZE to get that. */
479 event_lwp->syscall_state = TARGET_WAITKIND_SYSCALL_ENTRY;
481 if ((event == PTRACE_EVENT_FORK) || (event == PTRACE_EVENT_VFORK)
482 || (event == PTRACE_EVENT_CLONE))
485 unsigned long new_pid;
488 /* Get the pid of the new lwp. */
489 ptrace (PTRACE_GETEVENTMSG, lwpid_of (event_thr), (PTRACE_TYPE_ARG3) 0,
492 /* If we haven't already seen the new PID stop, wait for it now. */
493 if (!pull_pid_from_list (&stopped_pids, new_pid, &status))
495 /* The new child has a pending SIGSTOP. We can't affect it until it
496 hits the SIGSTOP, but we're already attached. */
498 ret = my_waitpid (new_pid, &status, __WALL);
501 perror_with_name ("waiting for new child");
502 else if (ret != new_pid)
503 warning ("wait returned unexpected PID %d", ret);
504 else if (!WIFSTOPPED (status))
505 warning ("wait returned unexpected status 0x%x", status);
508 if (event == PTRACE_EVENT_FORK || event == PTRACE_EVENT_VFORK)
510 struct process_info *parent_proc;
511 struct process_info *child_proc;
512 struct lwp_info *child_lwp;
513 struct thread_info *child_thr;
514 struct target_desc *tdesc;
516 ptid = ptid_build (new_pid, new_pid, 0);
520 debug_printf ("HEW: Got fork event from LWP %ld, "
522 ptid_get_lwp (ptid_of (event_thr)),
523 ptid_get_pid (ptid));
526 /* Add the new process to the tables and clone the breakpoint
527 lists of the parent. We need to do this even if the new process
528 will be detached, since we will need the process object and the
529 breakpoints to remove any breakpoints from memory when we
530 detach, and the client side will access registers. */
531 child_proc = linux_add_process (new_pid, 0);
532 gdb_assert (child_proc != NULL);
533 child_lwp = add_lwp (ptid);
534 gdb_assert (child_lwp != NULL);
535 child_lwp->stopped = 1;
536 child_lwp->must_set_ptrace_flags = 1;
537 child_lwp->status_pending_p = 0;
538 child_thr = get_lwp_thread (child_lwp);
539 child_thr->last_resume_kind = resume_stop;
540 child_thr->last_status.kind = TARGET_WAITKIND_STOPPED;
542 /* If we're suspending all threads, leave this one suspended
543 too. If the fork/clone parent is stepping over a breakpoint,
544 all other threads have been suspended already. Leave the
545 child suspended too. */
546 if (stopping_threads == STOPPING_AND_SUSPENDING_THREADS
547 || event_lwp->bp_reinsert != 0)
550 debug_printf ("HEW: leaving child suspended\n");
551 child_lwp->suspended = 1;
554 parent_proc = get_thread_process (event_thr);
555 child_proc->attached = parent_proc->attached;
557 if (event_lwp->bp_reinsert != 0
558 && can_software_single_step ()
559 && event == PTRACE_EVENT_VFORK)
561 /* If we leave single-step breakpoints there, child will
562 hit it, so uninsert single-step breakpoints from parent
563 (and child). Once vfork child is done, reinsert
564 them back to parent. */
565 uninsert_single_step_breakpoints (event_thr);
568 clone_all_breakpoints (child_thr, event_thr);
570 tdesc = XNEW (struct target_desc);
571 copy_target_description (tdesc, parent_proc->tdesc);
572 child_proc->tdesc = tdesc;
574 /* Clone arch-specific process data. */
575 if (the_low_target.new_fork != NULL)
576 the_low_target.new_fork (parent_proc, child_proc);
578 /* Save fork info in the parent thread. */
579 if (event == PTRACE_EVENT_FORK)
580 event_lwp->waitstatus.kind = TARGET_WAITKIND_FORKED;
581 else if (event == PTRACE_EVENT_VFORK)
582 event_lwp->waitstatus.kind = TARGET_WAITKIND_VFORKED;
584 event_lwp->waitstatus.value.related_pid = ptid;
586 /* The status_pending field contains bits denoting the
587 extended event, so when the pending event is handled,
588 the handler will look at lwp->waitstatus. */
589 event_lwp->status_pending_p = 1;
590 event_lwp->status_pending = wstat;
592 /* Link the threads until the parent event is passed on to
594 event_lwp->fork_relative = child_lwp;
595 child_lwp->fork_relative = event_lwp;
597 /* If the parent thread is doing step-over with single-step
598 breakpoints, the list of single-step breakpoints are cloned
599 from the parent's. Remove them from the child process.
600 In case of vfork, we'll reinsert them back once vforked
602 if (event_lwp->bp_reinsert != 0
603 && can_software_single_step ())
605 /* The child process is forked and stopped, so it is safe
606 to access its memory without stopping all other threads
607 from other processes. */
608 delete_single_step_breakpoints (child_thr);
610 gdb_assert (has_single_step_breakpoints (event_thr));
611 gdb_assert (!has_single_step_breakpoints (child_thr));
614 /* Report the event. */
619 debug_printf ("HEW: Got clone event "
620 "from LWP %ld, new child is LWP %ld\n",
621 lwpid_of (event_thr), new_pid);
623 ptid = ptid_build (pid_of (event_thr), new_pid, 0);
624 new_lwp = add_lwp (ptid);
626 /* Either we're going to immediately resume the new thread
627 or leave it stopped. linux_resume_one_lwp is a nop if it
628 thinks the thread is currently running, so set this first
629 before calling linux_resume_one_lwp. */
630 new_lwp->stopped = 1;
632 /* If we're suspending all threads, leave this one suspended
633 too. If the fork/clone parent is stepping over a breakpoint,
634 all other threads have been suspended already. Leave the
635 child suspended too. */
636 if (stopping_threads == STOPPING_AND_SUSPENDING_THREADS
637 || event_lwp->bp_reinsert != 0)
638 new_lwp->suspended = 1;
640 /* Normally we will get the pending SIGSTOP. But in some cases
641 we might get another signal delivered to the group first.
642 If we do get another signal, be sure not to lose it. */
643 if (WSTOPSIG (status) != SIGSTOP)
645 new_lwp->stop_expected = 1;
646 new_lwp->status_pending_p = 1;
647 new_lwp->status_pending = status;
649 else if (report_thread_events)
651 new_lwp->waitstatus.kind = TARGET_WAITKIND_THREAD_CREATED;
652 new_lwp->status_pending_p = 1;
653 new_lwp->status_pending = status;
656 /* Don't report the event. */
659 else if (event == PTRACE_EVENT_VFORK_DONE)
661 event_lwp->waitstatus.kind = TARGET_WAITKIND_VFORK_DONE;
663 if (event_lwp->bp_reinsert != 0 && can_software_single_step ())
665 reinsert_single_step_breakpoints (event_thr);
667 gdb_assert (has_single_step_breakpoints (event_thr));
670 /* Report the event. */
673 else if (event == PTRACE_EVENT_EXEC && report_exec_events)
675 struct process_info *proc;
676 VEC (int) *syscalls_to_catch;
682 debug_printf ("HEW: Got exec event from LWP %ld\n",
683 lwpid_of (event_thr));
686 /* Get the event ptid. */
687 event_ptid = ptid_of (event_thr);
688 event_pid = ptid_get_pid (event_ptid);
690 /* Save the syscall list from the execing process. */
691 proc = get_thread_process (event_thr);
692 syscalls_to_catch = proc->syscalls_to_catch;
693 proc->syscalls_to_catch = NULL;
695 /* Delete the execing process and all its threads. */
697 current_thread = NULL;
699 /* Create a new process/lwp/thread. */
700 proc = linux_add_process (event_pid, 0);
701 event_lwp = add_lwp (event_ptid);
702 event_thr = get_lwp_thread (event_lwp);
703 gdb_assert (current_thread == event_thr);
704 linux_arch_setup_thread (event_thr);
706 /* Set the event status. */
707 event_lwp->waitstatus.kind = TARGET_WAITKIND_EXECD;
708 event_lwp->waitstatus.value.execd_pathname
709 = xstrdup (linux_proc_pid_to_exec_file (lwpid_of (event_thr)));
711 /* Mark the exec status as pending. */
712 event_lwp->stopped = 1;
713 event_lwp->status_pending_p = 1;
714 event_lwp->status_pending = wstat;
715 event_thr->last_resume_kind = resume_continue;
716 event_thr->last_status.kind = TARGET_WAITKIND_IGNORE;
718 /* Update syscall state in the new lwp, effectively mid-syscall too. */
719 event_lwp->syscall_state = TARGET_WAITKIND_SYSCALL_ENTRY;
721 /* Restore the list to catch. Don't rely on the client, which is free
722 to avoid sending a new list when the architecture doesn't change.
723 Also, for ANY_SYSCALL, the architecture doesn't really matter. */
724 proc->syscalls_to_catch = syscalls_to_catch;
726 /* Report the event. */
727 *orig_event_lwp = event_lwp;
731 internal_error (__FILE__, __LINE__, _("unknown ptrace event %d"), event);
734 /* Return the PC as read from the regcache of LWP, without any
738 get_pc (struct lwp_info *lwp)
740 struct thread_info *saved_thread;
741 struct regcache *regcache;
744 if (the_low_target.get_pc == NULL)
747 saved_thread = current_thread;
748 current_thread = get_lwp_thread (lwp);
750 regcache = get_thread_regcache (current_thread, 1);
751 pc = (*the_low_target.get_pc) (regcache);
754 debug_printf ("pc is 0x%lx\n", (long) pc);
756 current_thread = saved_thread;
760 /* This function should only be called if LWP got a SYSCALL_SIGTRAP.
761 Fill *SYSNO with the syscall nr trapped. */
764 get_syscall_trapinfo (struct lwp_info *lwp, int *sysno)
766 struct thread_info *saved_thread;
767 struct regcache *regcache;
769 if (the_low_target.get_syscall_trapinfo == NULL)
771 /* If we cannot get the syscall trapinfo, report an unknown
772 system call number. */
773 *sysno = UNKNOWN_SYSCALL;
777 saved_thread = current_thread;
778 current_thread = get_lwp_thread (lwp);
780 regcache = get_thread_regcache (current_thread, 1);
781 (*the_low_target.get_syscall_trapinfo) (regcache, sysno);
784 debug_printf ("get_syscall_trapinfo sysno %d\n", *sysno);
786 current_thread = saved_thread;
789 static int check_stopped_by_watchpoint (struct lwp_info *child);
791 /* Called when the LWP stopped for a signal/trap. If it stopped for a
792 trap check what caused it (breakpoint, watchpoint, trace, etc.),
793 and save the result in the LWP's stop_reason field. If it stopped
794 for a breakpoint, decrement the PC if necessary on the lwp's
795 architecture. Returns true if we now have the LWP's stop PC. */
798 save_stop_reason (struct lwp_info *lwp)
801 CORE_ADDR sw_breakpoint_pc;
802 struct thread_info *saved_thread;
803 #if USE_SIGTRAP_SIGINFO
807 if (the_low_target.get_pc == NULL)
811 sw_breakpoint_pc = pc - the_low_target.decr_pc_after_break;
813 /* breakpoint_at reads from the current thread. */
814 saved_thread = current_thread;
815 current_thread = get_lwp_thread (lwp);
817 #if USE_SIGTRAP_SIGINFO
818 if (ptrace (PTRACE_GETSIGINFO, lwpid_of (current_thread),
819 (PTRACE_TYPE_ARG3) 0, &siginfo) == 0)
821 if (siginfo.si_signo == SIGTRAP)
823 if (GDB_ARCH_IS_TRAP_BRKPT (siginfo.si_code)
824 && GDB_ARCH_IS_TRAP_HWBKPT (siginfo.si_code))
826 /* The si_code is ambiguous on this arch -- check debug
828 if (!check_stopped_by_watchpoint (lwp))
829 lwp->stop_reason = TARGET_STOPPED_BY_SW_BREAKPOINT;
831 else if (GDB_ARCH_IS_TRAP_BRKPT (siginfo.si_code))
833 /* If we determine the LWP stopped for a SW breakpoint,
834 trust it. Particularly don't check watchpoint
835 registers, because at least on s390, we'd find
836 stopped-by-watchpoint as long as there's a watchpoint
838 lwp->stop_reason = TARGET_STOPPED_BY_SW_BREAKPOINT;
840 else if (GDB_ARCH_IS_TRAP_HWBKPT (siginfo.si_code))
842 /* This can indicate either a hardware breakpoint or
843 hardware watchpoint. Check debug registers. */
844 if (!check_stopped_by_watchpoint (lwp))
845 lwp->stop_reason = TARGET_STOPPED_BY_HW_BREAKPOINT;
847 else if (siginfo.si_code == TRAP_TRACE)
849 /* We may have single stepped an instruction that
850 triggered a watchpoint. In that case, on some
851 architectures (such as x86), instead of TRAP_HWBKPT,
852 si_code indicates TRAP_TRACE, and we need to check
853 the debug registers separately. */
854 if (!check_stopped_by_watchpoint (lwp))
855 lwp->stop_reason = TARGET_STOPPED_BY_SINGLE_STEP;
860 /* We may have just stepped a breakpoint instruction. E.g., in
861 non-stop mode, GDB first tells the thread A to step a range, and
862 then the user inserts a breakpoint inside the range. In that
863 case we need to report the breakpoint PC. */
864 if ((!lwp->stepping || lwp->stop_pc == sw_breakpoint_pc)
865 && (*the_low_target.breakpoint_at) (sw_breakpoint_pc))
866 lwp->stop_reason = TARGET_STOPPED_BY_SW_BREAKPOINT;
868 if (hardware_breakpoint_inserted_here (pc))
869 lwp->stop_reason = TARGET_STOPPED_BY_HW_BREAKPOINT;
871 if (lwp->stop_reason == TARGET_STOPPED_BY_NO_REASON)
872 check_stopped_by_watchpoint (lwp);
875 if (lwp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT)
879 struct thread_info *thr = get_lwp_thread (lwp);
881 debug_printf ("CSBB: %s stopped by software breakpoint\n",
882 target_pid_to_str (ptid_of (thr)));
885 /* Back up the PC if necessary. */
886 if (pc != sw_breakpoint_pc)
888 struct regcache *regcache
889 = get_thread_regcache (current_thread, 1);
890 (*the_low_target.set_pc) (regcache, sw_breakpoint_pc);
893 /* Update this so we record the correct stop PC below. */
894 pc = sw_breakpoint_pc;
896 else if (lwp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT)
900 struct thread_info *thr = get_lwp_thread (lwp);
902 debug_printf ("CSBB: %s stopped by hardware breakpoint\n",
903 target_pid_to_str (ptid_of (thr)));
906 else if (lwp->stop_reason == TARGET_STOPPED_BY_WATCHPOINT)
910 struct thread_info *thr = get_lwp_thread (lwp);
912 debug_printf ("CSBB: %s stopped by hardware watchpoint\n",
913 target_pid_to_str (ptid_of (thr)));
916 else if (lwp->stop_reason == TARGET_STOPPED_BY_SINGLE_STEP)
920 struct thread_info *thr = get_lwp_thread (lwp);
922 debug_printf ("CSBB: %s stopped by trace\n",
923 target_pid_to_str (ptid_of (thr)));
928 current_thread = saved_thread;
932 static struct lwp_info *
933 add_lwp (ptid_t ptid)
935 struct lwp_info *lwp;
937 lwp = XCNEW (struct lwp_info);
939 lwp->waitstatus.kind = TARGET_WAITKIND_IGNORE;
941 if (the_low_target.new_thread != NULL)
942 the_low_target.new_thread (lwp);
944 lwp->thread = add_thread (ptid, lwp);
949 /* Start an inferior process and returns its pid.
950 ALLARGS is a vector of program-name and args. */
953 linux_create_inferior (char *program, char **allargs)
955 struct lwp_info *new_lwp;
958 struct cleanup *restore_personality
959 = maybe_disable_address_space_randomization (disable_randomization);
961 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
967 perror_with_name ("fork");
972 ptrace (PTRACE_TRACEME, 0, (PTRACE_TYPE_ARG3) 0, (PTRACE_TYPE_ARG4) 0);
976 /* If gdbserver is connected to gdb via stdio, redirect the inferior's
977 stdout to stderr so that inferior i/o doesn't corrupt the connection.
978 Also, redirect stdin to /dev/null. */
979 if (remote_connection_is_stdio ())
982 open ("/dev/null", O_RDONLY);
984 if (write (2, "stdin/stdout redirected\n",
985 sizeof ("stdin/stdout redirected\n") - 1) < 0)
987 /* Errors ignored. */;
991 restore_original_signals_state ();
993 execv (program, allargs);
995 execvp (program, allargs);
997 fprintf (stderr, "Cannot exec %s: %s.\n", program,
1003 do_cleanups (restore_personality);
1005 linux_add_process (pid, 0);
1007 ptid = ptid_build (pid, pid, 0);
1008 new_lwp = add_lwp (ptid);
1009 new_lwp->must_set_ptrace_flags = 1;
1014 /* Implement the post_create_inferior target_ops method. */
1017 linux_post_create_inferior (void)
1019 struct lwp_info *lwp = get_thread_lwp (current_thread);
1021 linux_arch_setup ();
1023 if (lwp->must_set_ptrace_flags)
1025 struct process_info *proc = current_process ();
1026 int options = linux_low_ptrace_options (proc->attached);
1028 linux_enable_event_reporting (lwpid_of (current_thread), options);
1029 lwp->must_set_ptrace_flags = 0;
1033 /* Attach to an inferior process. Returns 0 on success, ERRNO on
1037 linux_attach_lwp (ptid_t ptid)
1039 struct lwp_info *new_lwp;
1040 int lwpid = ptid_get_lwp (ptid);
1042 if (ptrace (PTRACE_ATTACH, lwpid, (PTRACE_TYPE_ARG3) 0, (PTRACE_TYPE_ARG4) 0)
1046 new_lwp = add_lwp (ptid);
1048 /* We need to wait for SIGSTOP before being able to make the next
1049 ptrace call on this LWP. */
1050 new_lwp->must_set_ptrace_flags = 1;
1052 if (linux_proc_pid_is_stopped (lwpid))
1055 debug_printf ("Attached to a stopped process\n");
1057 /* The process is definitely stopped. It is in a job control
1058 stop, unless the kernel predates the TASK_STOPPED /
1059 TASK_TRACED distinction, in which case it might be in a
1060 ptrace stop. Make sure it is in a ptrace stop; from there we
1061 can kill it, signal it, et cetera.
1063 First make sure there is a pending SIGSTOP. Since we are
1064 already attached, the process can not transition from stopped
1065 to running without a PTRACE_CONT; so we know this signal will
1066 go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
1067 probably already in the queue (unless this kernel is old
1068 enough to use TASK_STOPPED for ptrace stops); but since
1069 SIGSTOP is not an RT signal, it can only be queued once. */
1070 kill_lwp (lwpid, SIGSTOP);
1072 /* Finally, resume the stopped process. This will deliver the
1073 SIGSTOP (or a higher priority signal, just like normal
1074 PTRACE_ATTACH), which we'll catch later on. */
1075 ptrace (PTRACE_CONT, lwpid, (PTRACE_TYPE_ARG3) 0, (PTRACE_TYPE_ARG4) 0);
1078 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
1079 brings it to a halt.
1081 There are several cases to consider here:
1083 1) gdbserver has already attached to the process and is being notified
1084 of a new thread that is being created.
1085 In this case we should ignore that SIGSTOP and resume the
1086 process. This is handled below by setting stop_expected = 1,
1087 and the fact that add_thread sets last_resume_kind ==
1090 2) This is the first thread (the process thread), and we're attaching
1091 to it via attach_inferior.
1092 In this case we want the process thread to stop.
1093 This is handled by having linux_attach set last_resume_kind ==
1094 resume_stop after we return.
1096 If the pid we are attaching to is also the tgid, we attach to and
1097 stop all the existing threads. Otherwise, we attach to pid and
1098 ignore any other threads in the same group as this pid.
1100 3) GDB is connecting to gdbserver and is requesting an enumeration of all
1102 In this case we want the thread to stop.
1103 FIXME: This case is currently not properly handled.
1104 We should wait for the SIGSTOP but don't. Things work apparently
1105 because enough time passes between when we ptrace (ATTACH) and when
1106 gdb makes the next ptrace call on the thread.
1108 On the other hand, if we are currently trying to stop all threads, we
1109 should treat the new thread as if we had sent it a SIGSTOP. This works
1110 because we are guaranteed that the add_lwp call above added us to the
1111 end of the list, and so the new thread has not yet reached
1112 wait_for_sigstop (but will). */
1113 new_lwp->stop_expected = 1;
1118 /* Callback for linux_proc_attach_tgid_threads. Attach to PTID if not
1119 already attached. Returns true if a new LWP is found, false
1123 attach_proc_task_lwp_callback (ptid_t ptid)
1125 /* Is this a new thread? */
1126 if (find_thread_ptid (ptid) == NULL)
1128 int lwpid = ptid_get_lwp (ptid);
1132 debug_printf ("Found new lwp %d\n", lwpid);
1134 err = linux_attach_lwp (ptid);
1136 /* Be quiet if we simply raced with the thread exiting. EPERM
1137 is returned if the thread's task still exists, and is marked
1138 as exited or zombie, as well as other conditions, so in that
1139 case, confirm the status in /proc/PID/status. */
1141 || (err == EPERM && linux_proc_pid_is_gone (lwpid)))
1145 debug_printf ("Cannot attach to lwp %d: "
1146 "thread is gone (%d: %s)\n",
1147 lwpid, err, strerror (err));
1152 warning (_("Cannot attach to lwp %d: %s"),
1154 linux_ptrace_attach_fail_reason_string (ptid, err));
1162 static void async_file_mark (void);
1164 /* Attach to PID. If PID is the tgid, attach to it and all
1168 linux_attach (unsigned long pid)
1170 struct process_info *proc;
1171 struct thread_info *initial_thread;
1172 ptid_t ptid = ptid_build (pid, pid, 0);
1175 /* Attach to PID. We will check for other threads
1177 err = linux_attach_lwp (ptid);
1179 error ("Cannot attach to process %ld: %s",
1180 pid, linux_ptrace_attach_fail_reason_string (ptid, err));
1182 proc = linux_add_process (pid, 1);
1184 /* Don't ignore the initial SIGSTOP if we just attached to this
1185 process. It will be collected by wait shortly. */
1186 initial_thread = find_thread_ptid (ptid_build (pid, pid, 0));
1187 initial_thread->last_resume_kind = resume_stop;
1189 /* We must attach to every LWP. If /proc is mounted, use that to
1190 find them now. On the one hand, the inferior may be using raw
1191 clone instead of using pthreads. On the other hand, even if it
1192 is using pthreads, GDB may not be connected yet (thread_db needs
1193 to do symbol lookups, through qSymbol). Also, thread_db walks
1194 structures in the inferior's address space to find the list of
1195 threads/LWPs, and those structures may well be corrupted. Note
1196 that once thread_db is loaded, we'll still use it to list threads
1197 and associate pthread info with each LWP. */
1198 linux_proc_attach_tgid_threads (pid, attach_proc_task_lwp_callback);
1200 /* GDB will shortly read the xml target description for this
1201 process, to figure out the process' architecture. But the target
1202 description is only filled in when the first process/thread in
1203 the thread group reports its initial PTRACE_ATTACH SIGSTOP. Do
1204 that now, otherwise, if GDB is fast enough, it could read the
1205 target description _before_ that initial stop. */
1208 struct lwp_info *lwp;
1210 ptid_t pid_ptid = pid_to_ptid (pid);
1212 lwpid = linux_wait_for_event_filtered (pid_ptid, pid_ptid,
1214 gdb_assert (lwpid > 0);
1216 lwp = find_lwp_pid (pid_to_ptid (lwpid));
1218 if (!WIFSTOPPED (wstat) || WSTOPSIG (wstat) != SIGSTOP)
1220 lwp->status_pending_p = 1;
1221 lwp->status_pending = wstat;
1224 initial_thread->last_resume_kind = resume_continue;
1228 gdb_assert (proc->tdesc != NULL);
1241 second_thread_of_pid_p (struct inferior_list_entry *entry, void *args)
1243 struct counter *counter = (struct counter *) args;
1245 if (ptid_get_pid (entry->id) == counter->pid)
1247 if (++counter->count > 1)
1255 last_thread_of_process_p (int pid)
1257 struct counter counter = { pid , 0 };
1259 return (find_inferior (&all_threads,
1260 second_thread_of_pid_p, &counter) == NULL);
1266 linux_kill_one_lwp (struct lwp_info *lwp)
1268 struct thread_info *thr = get_lwp_thread (lwp);
1269 int pid = lwpid_of (thr);
1271 /* PTRACE_KILL is unreliable. After stepping into a signal handler,
1272 there is no signal context, and ptrace(PTRACE_KILL) (or
1273 ptrace(PTRACE_CONT, SIGKILL), pretty much the same) acts like
1274 ptrace(CONT, pid, 0,0) and just resumes the tracee. A better
1275 alternative is to kill with SIGKILL. We only need one SIGKILL
1276 per process, not one for each thread. But since we still support
1277 support debugging programs using raw clone without CLONE_THREAD,
1278 we send one for each thread. For years, we used PTRACE_KILL
1279 only, so we're being a bit paranoid about some old kernels where
1280 PTRACE_KILL might work better (dubious if there are any such, but
1281 that's why it's paranoia), so we try SIGKILL first, PTRACE_KILL
1282 second, and so we're fine everywhere. */
1285 kill_lwp (pid, SIGKILL);
1288 int save_errno = errno;
1290 debug_printf ("LKL: kill_lwp (SIGKILL) %s, 0, 0 (%s)\n",
1291 target_pid_to_str (ptid_of (thr)),
1292 save_errno ? strerror (save_errno) : "OK");
1296 ptrace (PTRACE_KILL, pid, (PTRACE_TYPE_ARG3) 0, (PTRACE_TYPE_ARG4) 0);
1299 int save_errno = errno;
1301 debug_printf ("LKL: PTRACE_KILL %s, 0, 0 (%s)\n",
1302 target_pid_to_str (ptid_of (thr)),
1303 save_errno ? strerror (save_errno) : "OK");
1307 /* Kill LWP and wait for it to die. */
1310 kill_wait_lwp (struct lwp_info *lwp)
1312 struct thread_info *thr = get_lwp_thread (lwp);
1313 int pid = ptid_get_pid (ptid_of (thr));
1314 int lwpid = ptid_get_lwp (ptid_of (thr));
1319 debug_printf ("kwl: killing lwp %d, for pid: %d\n", lwpid, pid);
1323 linux_kill_one_lwp (lwp);
1325 /* Make sure it died. Notes:
1327 - The loop is most likely unnecessary.
1329 - We don't use linux_wait_for_event as that could delete lwps
1330 while we're iterating over them. We're not interested in
1331 any pending status at this point, only in making sure all
1332 wait status on the kernel side are collected until the
1335 - We don't use __WALL here as the __WALL emulation relies on
1336 SIGCHLD, and killing a stopped process doesn't generate
1337 one, nor an exit status.
1339 res = my_waitpid (lwpid, &wstat, 0);
1340 if (res == -1 && errno == ECHILD)
1341 res = my_waitpid (lwpid, &wstat, __WCLONE);
1342 } while (res > 0 && WIFSTOPPED (wstat));
1344 /* Even if it was stopped, the child may have already disappeared.
1345 E.g., if it was killed by SIGKILL. */
1346 if (res < 0 && errno != ECHILD)
1347 perror_with_name ("kill_wait_lwp");
1350 /* Callback for `find_inferior'. Kills an lwp of a given process,
1351 except the leader. */
1354 kill_one_lwp_callback (struct inferior_list_entry *entry, void *args)
1356 struct thread_info *thread = (struct thread_info *) entry;
1357 struct lwp_info *lwp = get_thread_lwp (thread);
1358 int pid = * (int *) args;
1360 if (ptid_get_pid (entry->id) != pid)
1363 /* We avoid killing the first thread here, because of a Linux kernel (at
1364 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
1365 the children get a chance to be reaped, it will remain a zombie
1368 if (lwpid_of (thread) == pid)
1371 debug_printf ("lkop: is last of process %s\n",
1372 target_pid_to_str (entry->id));
1376 kill_wait_lwp (lwp);
1381 linux_kill (int pid)
1383 struct process_info *process;
1384 struct lwp_info *lwp;
1386 process = find_process_pid (pid);
1387 if (process == NULL)
1390 /* If we're killing a running inferior, make sure it is stopped
1391 first, as PTRACE_KILL will not work otherwise. */
1392 stop_all_lwps (0, NULL);
1394 find_inferior (&all_threads, kill_one_lwp_callback , &pid);
1396 /* See the comment in linux_kill_one_lwp. We did not kill the first
1397 thread in the list, so do so now. */
1398 lwp = find_lwp_pid (pid_to_ptid (pid));
1403 debug_printf ("lk_1: cannot find lwp for pid: %d\n",
1407 kill_wait_lwp (lwp);
1409 the_target->mourn (process);
1411 /* Since we presently can only stop all lwps of all processes, we
1412 need to unstop lwps of other processes. */
1413 unstop_all_lwps (0, NULL);
1417 /* Get pending signal of THREAD, for detaching purposes. This is the
1418 signal the thread last stopped for, which we need to deliver to the
1419 thread when detaching, otherwise, it'd be suppressed/lost. */
1422 get_detach_signal (struct thread_info *thread)
1424 enum gdb_signal signo = GDB_SIGNAL_0;
1426 struct lwp_info *lp = get_thread_lwp (thread);
1428 if (lp->status_pending_p)
1429 status = lp->status_pending;
1432 /* If the thread had been suspended by gdbserver, and it stopped
1433 cleanly, then it'll have stopped with SIGSTOP. But we don't
1434 want to deliver that SIGSTOP. */
1435 if (thread->last_status.kind != TARGET_WAITKIND_STOPPED
1436 || thread->last_status.value.sig == GDB_SIGNAL_0)
1439 /* Otherwise, we may need to deliver the signal we
1441 status = lp->last_status;
1444 if (!WIFSTOPPED (status))
1447 debug_printf ("GPS: lwp %s hasn't stopped: no pending signal\n",
1448 target_pid_to_str (ptid_of (thread)));
1452 /* Extended wait statuses aren't real SIGTRAPs. */
1453 if (WSTOPSIG (status) == SIGTRAP && linux_is_extended_waitstatus (status))
1456 debug_printf ("GPS: lwp %s had stopped with extended "
1457 "status: no pending signal\n",
1458 target_pid_to_str (ptid_of (thread)));
1462 signo = gdb_signal_from_host (WSTOPSIG (status));
1464 if (program_signals_p && !program_signals[signo])
1467 debug_printf ("GPS: lwp %s had signal %s, but it is in nopass state\n",
1468 target_pid_to_str (ptid_of (thread)),
1469 gdb_signal_to_string (signo));
1472 else if (!program_signals_p
1473 /* If we have no way to know which signals GDB does not
1474 want to have passed to the program, assume
1475 SIGTRAP/SIGINT, which is GDB's default. */
1476 && (signo == GDB_SIGNAL_TRAP || signo == GDB_SIGNAL_INT))
1479 debug_printf ("GPS: lwp %s had signal %s, "
1480 "but we don't know if we should pass it. "
1481 "Default to not.\n",
1482 target_pid_to_str (ptid_of (thread)),
1483 gdb_signal_to_string (signo));
1489 debug_printf ("GPS: lwp %s has pending signal %s: delivering it.\n",
1490 target_pid_to_str (ptid_of (thread)),
1491 gdb_signal_to_string (signo));
1493 return WSTOPSIG (status);
1497 /* Detach from LWP. */
1500 linux_detach_one_lwp (struct lwp_info *lwp)
1502 struct thread_info *thread = get_lwp_thread (lwp);
1506 /* If there is a pending SIGSTOP, get rid of it. */
1507 if (lwp->stop_expected)
1510 debug_printf ("Sending SIGCONT to %s\n",
1511 target_pid_to_str (ptid_of (thread)));
1513 kill_lwp (lwpid_of (thread), SIGCONT);
1514 lwp->stop_expected = 0;
1517 /* Pass on any pending signal for this thread. */
1518 sig = get_detach_signal (thread);
1520 /* Preparing to resume may try to write registers, and fail if the
1521 lwp is zombie. If that happens, ignore the error. We'll handle
1522 it below, when detach fails with ESRCH. */
1525 /* Flush any pending changes to the process's registers. */
1526 regcache_invalidate_thread (thread);
1528 /* Finally, let it resume. */
1529 if (the_low_target.prepare_to_resume != NULL)
1530 the_low_target.prepare_to_resume (lwp);
1532 CATCH (ex, RETURN_MASK_ERROR)
1534 if (!check_ptrace_stopped_lwp_gone (lwp))
1535 throw_exception (ex);
1539 lwpid = lwpid_of (thread);
1540 if (ptrace (PTRACE_DETACH, lwpid, (PTRACE_TYPE_ARG3) 0,
1541 (PTRACE_TYPE_ARG4) (long) sig) < 0)
1543 int save_errno = errno;
1545 /* We know the thread exists, so ESRCH must mean the lwp is
1546 zombie. This can happen if one of the already-detached
1547 threads exits the whole thread group. In that case we're
1548 still attached, and must reap the lwp. */
1549 if (save_errno == ESRCH)
1553 ret = my_waitpid (lwpid, &status, __WALL);
1556 warning (_("Couldn't reap LWP %d while detaching: %s"),
1557 lwpid, strerror (errno));
1559 else if (!WIFEXITED (status) && !WIFSIGNALED (status))
1561 warning (_("Reaping LWP %d while detaching "
1562 "returned unexpected status 0x%x"),
1568 error (_("Can't detach %s: %s"),
1569 target_pid_to_str (ptid_of (thread)),
1570 strerror (save_errno));
1573 else if (debug_threads)
1575 debug_printf ("PTRACE_DETACH (%s, %s, 0) (OK)\n",
1576 target_pid_to_str (ptid_of (thread)),
1583 /* Callback for find_inferior. Detaches from non-leader threads of a
1587 linux_detach_lwp_callback (struct inferior_list_entry *entry, void *args)
1589 struct thread_info *thread = (struct thread_info *) entry;
1590 struct lwp_info *lwp = get_thread_lwp (thread);
1591 int pid = *(int *) args;
1592 int lwpid = lwpid_of (thread);
1594 /* Skip other processes. */
1595 if (ptid_get_pid (entry->id) != pid)
1598 /* We don't actually detach from the thread group leader just yet.
1599 If the thread group exits, we must reap the zombie clone lwps
1600 before we're able to reap the leader. */
1601 if (ptid_get_pid (entry->id) == lwpid)
1604 linux_detach_one_lwp (lwp);
1609 linux_detach (int pid)
1611 struct process_info *process;
1612 struct lwp_info *main_lwp;
1614 process = find_process_pid (pid);
1615 if (process == NULL)
1618 /* As there's a step over already in progress, let it finish first,
1619 otherwise nesting a stabilize_threads operation on top gets real
1621 complete_ongoing_step_over ();
1623 /* Stop all threads before detaching. First, ptrace requires that
1624 the thread is stopped to sucessfully detach. Second, thread_db
1625 may need to uninstall thread event breakpoints from memory, which
1626 only works with a stopped process anyway. */
1627 stop_all_lwps (0, NULL);
1629 #ifdef USE_THREAD_DB
1630 thread_db_detach (process);
1633 /* Stabilize threads (move out of jump pads). */
1634 stabilize_threads ();
1636 /* Detach from the clone lwps first. If the thread group exits just
1637 while we're detaching, we must reap the clone lwps before we're
1638 able to reap the leader. */
1639 find_inferior (&all_threads, linux_detach_lwp_callback, &pid);
1641 main_lwp = find_lwp_pid (pid_to_ptid (pid));
1642 linux_detach_one_lwp (main_lwp);
1644 the_target->mourn (process);
1646 /* Since we presently can only stop all lwps of all processes, we
1647 need to unstop lwps of other processes. */
1648 unstop_all_lwps (0, NULL);
1652 /* Remove all LWPs that belong to process PROC from the lwp list. */
1655 delete_lwp_callback (struct inferior_list_entry *entry, void *proc)
1657 struct thread_info *thread = (struct thread_info *) entry;
1658 struct lwp_info *lwp = get_thread_lwp (thread);
1659 struct process_info *process = (struct process_info *) proc;
1661 if (pid_of (thread) == pid_of (process))
1668 linux_mourn (struct process_info *process)
1670 struct process_info_private *priv;
1672 #ifdef USE_THREAD_DB
1673 thread_db_mourn (process);
1676 find_inferior (&all_threads, delete_lwp_callback, process);
1678 /* Freeing all private data. */
1679 priv = process->priv;
1680 free (priv->arch_private);
1682 process->priv = NULL;
1684 remove_process (process);
1688 linux_join (int pid)
1693 ret = my_waitpid (pid, &status, 0);
1694 if (WIFEXITED (status) || WIFSIGNALED (status))
1696 } while (ret != -1 || errno != ECHILD);
1699 /* Return nonzero if the given thread is still alive. */
1701 linux_thread_alive (ptid_t ptid)
1703 struct lwp_info *lwp = find_lwp_pid (ptid);
1705 /* We assume we always know if a thread exits. If a whole process
1706 exited but we still haven't been able to report it to GDB, we'll
1707 hold on to the last lwp of the dead process. */
1709 return !lwp_is_marked_dead (lwp);
1714 /* Return 1 if this lwp still has an interesting status pending. If
1715 not (e.g., it had stopped for a breakpoint that is gone), return
1719 thread_still_has_status_pending_p (struct thread_info *thread)
1721 struct lwp_info *lp = get_thread_lwp (thread);
1723 if (!lp->status_pending_p)
1726 if (thread->last_resume_kind != resume_stop
1727 && (lp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT
1728 || lp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT))
1730 struct thread_info *saved_thread;
1734 gdb_assert (lp->last_status != 0);
1738 saved_thread = current_thread;
1739 current_thread = thread;
1741 if (pc != lp->stop_pc)
1744 debug_printf ("PC of %ld changed\n",
1749 #if !USE_SIGTRAP_SIGINFO
1750 else if (lp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT
1751 && !(*the_low_target.breakpoint_at) (pc))
1754 debug_printf ("previous SW breakpoint of %ld gone\n",
1758 else if (lp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT
1759 && !hardware_breakpoint_inserted_here (pc))
1762 debug_printf ("previous HW breakpoint of %ld gone\n",
1768 current_thread = saved_thread;
1773 debug_printf ("discarding pending breakpoint status\n");
1774 lp->status_pending_p = 0;
1782 /* Returns true if LWP is resumed from the client's perspective. */
1785 lwp_resumed (struct lwp_info *lwp)
1787 struct thread_info *thread = get_lwp_thread (lwp);
1789 if (thread->last_resume_kind != resume_stop)
1792 /* Did gdb send us a `vCont;t', but we haven't reported the
1793 corresponding stop to gdb yet? If so, the thread is still
1794 resumed/running from gdb's perspective. */
1795 if (thread->last_resume_kind == resume_stop
1796 && thread->last_status.kind == TARGET_WAITKIND_IGNORE)
1802 /* Return 1 if this lwp has an interesting status pending. */
1804 status_pending_p_callback (struct inferior_list_entry *entry, void *arg)
1806 struct thread_info *thread = (struct thread_info *) entry;
1807 struct lwp_info *lp = get_thread_lwp (thread);
1808 ptid_t ptid = * (ptid_t *) arg;
1810 /* Check if we're only interested in events from a specific process
1811 or a specific LWP. */
1812 if (!ptid_match (ptid_of (thread), ptid))
1815 if (!lwp_resumed (lp))
1818 if (lp->status_pending_p
1819 && !thread_still_has_status_pending_p (thread))
1821 linux_resume_one_lwp (lp, lp->stepping, GDB_SIGNAL_0, NULL);
1825 return lp->status_pending_p;
1829 same_lwp (struct inferior_list_entry *entry, void *data)
1831 ptid_t ptid = *(ptid_t *) data;
1834 if (ptid_get_lwp (ptid) != 0)
1835 lwp = ptid_get_lwp (ptid);
1837 lwp = ptid_get_pid (ptid);
1839 if (ptid_get_lwp (entry->id) == lwp)
1846 find_lwp_pid (ptid_t ptid)
1848 struct inferior_list_entry *thread
1849 = find_inferior (&all_threads, same_lwp, &ptid);
1854 return get_thread_lwp ((struct thread_info *) thread);
1857 /* Return the number of known LWPs in the tgid given by PID. */
1862 struct inferior_list_entry *inf, *tmp;
1865 ALL_INFERIORS (&all_threads, inf, tmp)
1867 if (ptid_get_pid (inf->id) == pid)
1874 /* The arguments passed to iterate_over_lwps. */
1876 struct iterate_over_lwps_args
1878 /* The FILTER argument passed to iterate_over_lwps. */
1881 /* The CALLBACK argument passed to iterate_over_lwps. */
1882 iterate_over_lwps_ftype *callback;
1884 /* The DATA argument passed to iterate_over_lwps. */
1888 /* Callback for find_inferior used by iterate_over_lwps to filter
1889 calls to the callback supplied to that function. Returning a
1890 nonzero value causes find_inferiors to stop iterating and return
1891 the current inferior_list_entry. Returning zero indicates that
1892 find_inferiors should continue iterating. */
1895 iterate_over_lwps_filter (struct inferior_list_entry *entry, void *args_p)
1897 struct iterate_over_lwps_args *args
1898 = (struct iterate_over_lwps_args *) args_p;
1900 if (ptid_match (entry->id, args->filter))
1902 struct thread_info *thr = (struct thread_info *) entry;
1903 struct lwp_info *lwp = get_thread_lwp (thr);
1905 return (*args->callback) (lwp, args->data);
1911 /* See nat/linux-nat.h. */
1914 iterate_over_lwps (ptid_t filter,
1915 iterate_over_lwps_ftype callback,
1918 struct iterate_over_lwps_args args = {filter, callback, data};
1919 struct inferior_list_entry *entry;
1921 entry = find_inferior (&all_threads, iterate_over_lwps_filter, &args);
1925 return get_thread_lwp ((struct thread_info *) entry);
1928 /* Detect zombie thread group leaders, and "exit" them. We can't reap
1929 their exits until all other threads in the group have exited. */
1932 check_zombie_leaders (void)
1934 struct process_info *proc, *tmp;
1936 ALL_PROCESSES (proc, tmp)
1938 pid_t leader_pid = pid_of (proc);
1939 struct lwp_info *leader_lp;
1941 leader_lp = find_lwp_pid (pid_to_ptid (leader_pid));
1944 debug_printf ("leader_pid=%d, leader_lp!=NULL=%d, "
1945 "num_lwps=%d, zombie=%d\n",
1946 leader_pid, leader_lp!= NULL, num_lwps (leader_pid),
1947 linux_proc_pid_is_zombie (leader_pid));
1949 if (leader_lp != NULL && !leader_lp->stopped
1950 /* Check if there are other threads in the group, as we may
1951 have raced with the inferior simply exiting. */
1952 && !last_thread_of_process_p (leader_pid)
1953 && linux_proc_pid_is_zombie (leader_pid))
1955 /* A leader zombie can mean one of two things:
1957 - It exited, and there's an exit status pending
1958 available, or only the leader exited (not the whole
1959 program). In the latter case, we can't waitpid the
1960 leader's exit status until all other threads are gone.
1962 - There are 3 or more threads in the group, and a thread
1963 other than the leader exec'd. On an exec, the Linux
1964 kernel destroys all other threads (except the execing
1965 one) in the thread group, and resets the execing thread's
1966 tid to the tgid. No exit notification is sent for the
1967 execing thread -- from the ptracer's perspective, it
1968 appears as though the execing thread just vanishes.
1969 Until we reap all other threads except the leader and the
1970 execing thread, the leader will be zombie, and the
1971 execing thread will be in `D (disc sleep)'. As soon as
1972 all other threads are reaped, the execing thread changes
1973 it's tid to the tgid, and the previous (zombie) leader
1974 vanishes, giving place to the "new" leader. We could try
1975 distinguishing the exit and exec cases, by waiting once
1976 more, and seeing if something comes out, but it doesn't
1977 sound useful. The previous leader _does_ go away, and
1978 we'll re-add the new one once we see the exec event
1979 (which is just the same as what would happen if the
1980 previous leader did exit voluntarily before some other
1985 "CZL: Thread group leader %d zombie "
1986 "(it exited, or another thread execd).\n",
1989 delete_lwp (leader_lp);
1994 /* Callback for `find_inferior'. Returns the first LWP that is not
1995 stopped. ARG is a PTID filter. */
1998 not_stopped_callback (struct inferior_list_entry *entry, void *arg)
2000 struct thread_info *thr = (struct thread_info *) entry;
2001 struct lwp_info *lwp;
2002 ptid_t filter = *(ptid_t *) arg;
2004 if (!ptid_match (ptid_of (thr), filter))
2007 lwp = get_thread_lwp (thr);
2014 /* Increment LWP's suspend count. */
2017 lwp_suspended_inc (struct lwp_info *lwp)
2021 if (debug_threads && lwp->suspended > 4)
2023 struct thread_info *thread = get_lwp_thread (lwp);
2025 debug_printf ("LWP %ld has a suspiciously high suspend count,"
2026 " suspended=%d\n", lwpid_of (thread), lwp->suspended);
2030 /* Decrement LWP's suspend count. */
2033 lwp_suspended_decr (struct lwp_info *lwp)
2037 if (lwp->suspended < 0)
2039 struct thread_info *thread = get_lwp_thread (lwp);
2041 internal_error (__FILE__, __LINE__,
2042 "unsuspend LWP %ld, suspended=%d\n", lwpid_of (thread),
2047 /* This function should only be called if the LWP got a SIGTRAP.
2049 Handle any tracepoint steps or hits. Return true if a tracepoint
2050 event was handled, 0 otherwise. */
2053 handle_tracepoints (struct lwp_info *lwp)
2055 struct thread_info *tinfo = get_lwp_thread (lwp);
2056 int tpoint_related_event = 0;
2058 gdb_assert (lwp->suspended == 0);
2060 /* If this tracepoint hit causes a tracing stop, we'll immediately
2061 uninsert tracepoints. To do this, we temporarily pause all
2062 threads, unpatch away, and then unpause threads. We need to make
2063 sure the unpausing doesn't resume LWP too. */
2064 lwp_suspended_inc (lwp);
2066 /* And we need to be sure that any all-threads-stopping doesn't try
2067 to move threads out of the jump pads, as it could deadlock the
2068 inferior (LWP could be in the jump pad, maybe even holding the
2071 /* Do any necessary step collect actions. */
2072 tpoint_related_event |= tracepoint_finished_step (tinfo, lwp->stop_pc);
2074 tpoint_related_event |= handle_tracepoint_bkpts (tinfo, lwp->stop_pc);
2076 /* See if we just hit a tracepoint and do its main collect
2078 tpoint_related_event |= tracepoint_was_hit (tinfo, lwp->stop_pc);
2080 lwp_suspended_decr (lwp);
2082 gdb_assert (lwp->suspended == 0);
2083 gdb_assert (!stabilizing_threads || lwp->collecting_fast_tracepoint);
2085 if (tpoint_related_event)
2088 debug_printf ("got a tracepoint event\n");
2095 /* Convenience wrapper. Returns true if LWP is presently collecting a
2099 linux_fast_tracepoint_collecting (struct lwp_info *lwp,
2100 struct fast_tpoint_collect_status *status)
2102 CORE_ADDR thread_area;
2103 struct thread_info *thread = get_lwp_thread (lwp);
2105 if (the_low_target.get_thread_area == NULL)
2108 /* Get the thread area address. This is used to recognize which
2109 thread is which when tracing with the in-process agent library.
2110 We don't read anything from the address, and treat it as opaque;
2111 it's the address itself that we assume is unique per-thread. */
2112 if ((*the_low_target.get_thread_area) (lwpid_of (thread), &thread_area) == -1)
2115 return fast_tracepoint_collecting (thread_area, lwp->stop_pc, status);
2118 /* The reason we resume in the caller, is because we want to be able
2119 to pass lwp->status_pending as WSTAT, and we need to clear
2120 status_pending_p before resuming, otherwise, linux_resume_one_lwp
2121 refuses to resume. */
2124 maybe_move_out_of_jump_pad (struct lwp_info *lwp, int *wstat)
2126 struct thread_info *saved_thread;
2128 saved_thread = current_thread;
2129 current_thread = get_lwp_thread (lwp);
2132 || (WIFSTOPPED (*wstat) && WSTOPSIG (*wstat) != SIGTRAP))
2133 && supports_fast_tracepoints ()
2134 && agent_loaded_p ())
2136 struct fast_tpoint_collect_status status;
2140 debug_printf ("Checking whether LWP %ld needs to move out of the "
2142 lwpid_of (current_thread));
2144 r = linux_fast_tracepoint_collecting (lwp, &status);
2147 || (WSTOPSIG (*wstat) != SIGILL
2148 && WSTOPSIG (*wstat) != SIGFPE
2149 && WSTOPSIG (*wstat) != SIGSEGV
2150 && WSTOPSIG (*wstat) != SIGBUS))
2152 lwp->collecting_fast_tracepoint = r;
2156 if (r == 1 && lwp->exit_jump_pad_bkpt == NULL)
2158 /* Haven't executed the original instruction yet.
2159 Set breakpoint there, and wait till it's hit,
2160 then single-step until exiting the jump pad. */
2161 lwp->exit_jump_pad_bkpt
2162 = set_breakpoint_at (status.adjusted_insn_addr, NULL);
2166 debug_printf ("Checking whether LWP %ld needs to move out of "
2167 "the jump pad...it does\n",
2168 lwpid_of (current_thread));
2169 current_thread = saved_thread;
2176 /* If we get a synchronous signal while collecting, *and*
2177 while executing the (relocated) original instruction,
2178 reset the PC to point at the tpoint address, before
2179 reporting to GDB. Otherwise, it's an IPA lib bug: just
2180 report the signal to GDB, and pray for the best. */
2182 lwp->collecting_fast_tracepoint = 0;
2185 && (status.adjusted_insn_addr <= lwp->stop_pc
2186 && lwp->stop_pc < status.adjusted_insn_addr_end))
2189 struct regcache *regcache;
2191 /* The si_addr on a few signals references the address
2192 of the faulting instruction. Adjust that as
2194 if ((WSTOPSIG (*wstat) == SIGILL
2195 || WSTOPSIG (*wstat) == SIGFPE
2196 || WSTOPSIG (*wstat) == SIGBUS
2197 || WSTOPSIG (*wstat) == SIGSEGV)
2198 && ptrace (PTRACE_GETSIGINFO, lwpid_of (current_thread),
2199 (PTRACE_TYPE_ARG3) 0, &info) == 0
2200 /* Final check just to make sure we don't clobber
2201 the siginfo of non-kernel-sent signals. */
2202 && (uintptr_t) info.si_addr == lwp->stop_pc)
2204 info.si_addr = (void *) (uintptr_t) status.tpoint_addr;
2205 ptrace (PTRACE_SETSIGINFO, lwpid_of (current_thread),
2206 (PTRACE_TYPE_ARG3) 0, &info);
2209 regcache = get_thread_regcache (current_thread, 1);
2210 (*the_low_target.set_pc) (regcache, status.tpoint_addr);
2211 lwp->stop_pc = status.tpoint_addr;
2213 /* Cancel any fast tracepoint lock this thread was
2215 force_unlock_trace_buffer ();
2218 if (lwp->exit_jump_pad_bkpt != NULL)
2221 debug_printf ("Cancelling fast exit-jump-pad: removing bkpt. "
2222 "stopping all threads momentarily.\n");
2224 stop_all_lwps (1, lwp);
2226 delete_breakpoint (lwp->exit_jump_pad_bkpt);
2227 lwp->exit_jump_pad_bkpt = NULL;
2229 unstop_all_lwps (1, lwp);
2231 gdb_assert (lwp->suspended >= 0);
2237 debug_printf ("Checking whether LWP %ld needs to move out of the "
2239 lwpid_of (current_thread));
2241 current_thread = saved_thread;
2245 /* Enqueue one signal in the "signals to report later when out of the
2249 enqueue_one_deferred_signal (struct lwp_info *lwp, int *wstat)
2251 struct pending_signals *p_sig;
2252 struct thread_info *thread = get_lwp_thread (lwp);
2255 debug_printf ("Deferring signal %d for LWP %ld.\n",
2256 WSTOPSIG (*wstat), lwpid_of (thread));
2260 struct pending_signals *sig;
2262 for (sig = lwp->pending_signals_to_report;
2265 debug_printf (" Already queued %d\n",
2268 debug_printf (" (no more currently queued signals)\n");
2271 /* Don't enqueue non-RT signals if they are already in the deferred
2272 queue. (SIGSTOP being the easiest signal to see ending up here
2274 if (WSTOPSIG (*wstat) < __SIGRTMIN)
2276 struct pending_signals *sig;
2278 for (sig = lwp->pending_signals_to_report;
2282 if (sig->signal == WSTOPSIG (*wstat))
2285 debug_printf ("Not requeuing already queued non-RT signal %d"
2294 p_sig = XCNEW (struct pending_signals);
2295 p_sig->prev = lwp->pending_signals_to_report;
2296 p_sig->signal = WSTOPSIG (*wstat);
2298 ptrace (PTRACE_GETSIGINFO, lwpid_of (thread), (PTRACE_TYPE_ARG3) 0,
2301 lwp->pending_signals_to_report = p_sig;
2304 /* Dequeue one signal from the "signals to report later when out of
2305 the jump pad" list. */
2308 dequeue_one_deferred_signal (struct lwp_info *lwp, int *wstat)
2310 struct thread_info *thread = get_lwp_thread (lwp);
2312 if (lwp->pending_signals_to_report != NULL)
2314 struct pending_signals **p_sig;
2316 p_sig = &lwp->pending_signals_to_report;
2317 while ((*p_sig)->prev != NULL)
2318 p_sig = &(*p_sig)->prev;
2320 *wstat = W_STOPCODE ((*p_sig)->signal);
2321 if ((*p_sig)->info.si_signo != 0)
2322 ptrace (PTRACE_SETSIGINFO, lwpid_of (thread), (PTRACE_TYPE_ARG3) 0,
2328 debug_printf ("Reporting deferred signal %d for LWP %ld.\n",
2329 WSTOPSIG (*wstat), lwpid_of (thread));
2333 struct pending_signals *sig;
2335 for (sig = lwp->pending_signals_to_report;
2338 debug_printf (" Still queued %d\n",
2341 debug_printf (" (no more queued signals)\n");
2350 /* Fetch the possibly triggered data watchpoint info and store it in
2353 On some archs, like x86, that use debug registers to set
2354 watchpoints, it's possible that the way to know which watched
2355 address trapped, is to check the register that is used to select
2356 which address to watch. Problem is, between setting the watchpoint
2357 and reading back which data address trapped, the user may change
2358 the set of watchpoints, and, as a consequence, GDB changes the
2359 debug registers in the inferior. To avoid reading back a stale
2360 stopped-data-address when that happens, we cache in LP the fact
2361 that a watchpoint trapped, and the corresponding data address, as
2362 soon as we see CHILD stop with a SIGTRAP. If GDB changes the debug
2363 registers meanwhile, we have the cached data we can rely on. */
2366 check_stopped_by_watchpoint (struct lwp_info *child)
2368 if (the_low_target.stopped_by_watchpoint != NULL)
2370 struct thread_info *saved_thread;
2372 saved_thread = current_thread;
2373 current_thread = get_lwp_thread (child);
2375 if (the_low_target.stopped_by_watchpoint ())
2377 child->stop_reason = TARGET_STOPPED_BY_WATCHPOINT;
2379 if (the_low_target.stopped_data_address != NULL)
2380 child->stopped_data_address
2381 = the_low_target.stopped_data_address ();
2383 child->stopped_data_address = 0;
2386 current_thread = saved_thread;
2389 return child->stop_reason == TARGET_STOPPED_BY_WATCHPOINT;
2392 /* Return the ptrace options that we want to try to enable. */
2395 linux_low_ptrace_options (int attached)
2400 options |= PTRACE_O_EXITKILL;
2402 if (report_fork_events)
2403 options |= PTRACE_O_TRACEFORK;
2405 if (report_vfork_events)
2406 options |= (PTRACE_O_TRACEVFORK | PTRACE_O_TRACEVFORKDONE);
2408 if (report_exec_events)
2409 options |= PTRACE_O_TRACEEXEC;
2411 options |= PTRACE_O_TRACESYSGOOD;
2416 /* Do low-level handling of the event, and check if we should go on
2417 and pass it to caller code. Return the affected lwp if we are, or
2420 static struct lwp_info *
2421 linux_low_filter_event (int lwpid, int wstat)
2423 struct lwp_info *child;
2424 struct thread_info *thread;
2425 int have_stop_pc = 0;
2427 child = find_lwp_pid (pid_to_ptid (lwpid));
2429 /* Check for stop events reported by a process we didn't already
2430 know about - anything not already in our LWP list.
2432 If we're expecting to receive stopped processes after
2433 fork, vfork, and clone events, then we'll just add the
2434 new one to our list and go back to waiting for the event
2435 to be reported - the stopped process might be returned
2436 from waitpid before or after the event is.
2438 But note the case of a non-leader thread exec'ing after the
2439 leader having exited, and gone from our lists (because
2440 check_zombie_leaders deleted it). The non-leader thread
2441 changes its tid to the tgid. */
2443 if (WIFSTOPPED (wstat) && child == NULL && WSTOPSIG (wstat) == SIGTRAP
2444 && linux_ptrace_get_extended_event (wstat) == PTRACE_EVENT_EXEC)
2448 /* A multi-thread exec after we had seen the leader exiting. */
2451 debug_printf ("LLW: Re-adding thread group leader LWP %d"
2452 "after exec.\n", lwpid);
2455 child_ptid = ptid_build (lwpid, lwpid, 0);
2456 child = add_lwp (child_ptid);
2458 current_thread = child->thread;
2461 /* If we didn't find a process, one of two things presumably happened:
2462 - A process we started and then detached from has exited. Ignore it.
2463 - A process we are controlling has forked and the new child's stop
2464 was reported to us by the kernel. Save its PID. */
2465 if (child == NULL && WIFSTOPPED (wstat))
2467 add_to_pid_list (&stopped_pids, lwpid, wstat);
2470 else if (child == NULL)
2473 thread = get_lwp_thread (child);
2477 child->last_status = wstat;
2479 /* Check if the thread has exited. */
2480 if ((WIFEXITED (wstat) || WIFSIGNALED (wstat)))
2483 debug_printf ("LLFE: %d exited.\n", lwpid);
2485 if (finish_step_over (child))
2487 /* Unsuspend all other LWPs, and set them back running again. */
2488 unsuspend_all_lwps (child);
2491 /* If there is at least one more LWP, then the exit signal was
2492 not the end of the debugged application and should be
2493 ignored, unless GDB wants to hear about thread exits. */
2494 if (report_thread_events
2495 || last_thread_of_process_p (pid_of (thread)))
2497 /* Since events are serialized to GDB core, and we can't
2498 report this one right now. Leave the status pending for
2499 the next time we're able to report it. */
2500 mark_lwp_dead (child, wstat);
2510 gdb_assert (WIFSTOPPED (wstat));
2512 if (WIFSTOPPED (wstat))
2514 struct process_info *proc;
2516 /* Architecture-specific setup after inferior is running. */
2517 proc = find_process_pid (pid_of (thread));
2518 if (proc->tdesc == NULL)
2522 /* This needs to happen after we have attached to the
2523 inferior and it is stopped for the first time, but
2524 before we access any inferior registers. */
2525 linux_arch_setup_thread (thread);
2529 /* The process is started, but GDBserver will do
2530 architecture-specific setup after the program stops at
2531 the first instruction. */
2532 child->status_pending_p = 1;
2533 child->status_pending = wstat;
2539 if (WIFSTOPPED (wstat) && child->must_set_ptrace_flags)
2541 struct process_info *proc = find_process_pid (pid_of (thread));
2542 int options = linux_low_ptrace_options (proc->attached);
2544 linux_enable_event_reporting (lwpid, options);
2545 child->must_set_ptrace_flags = 0;
2548 /* Always update syscall_state, even if it will be filtered later. */
2549 if (WIFSTOPPED (wstat) && WSTOPSIG (wstat) == SYSCALL_SIGTRAP)
2551 child->syscall_state
2552 = (child->syscall_state == TARGET_WAITKIND_SYSCALL_ENTRY
2553 ? TARGET_WAITKIND_SYSCALL_RETURN
2554 : TARGET_WAITKIND_SYSCALL_ENTRY);
2558 /* Almost all other ptrace-stops are known to be outside of system
2559 calls, with further exceptions in handle_extended_wait. */
2560 child->syscall_state = TARGET_WAITKIND_IGNORE;
2563 /* Be careful to not overwrite stop_pc until save_stop_reason is
2565 if (WIFSTOPPED (wstat) && WSTOPSIG (wstat) == SIGTRAP
2566 && linux_is_extended_waitstatus (wstat))
2568 child->stop_pc = get_pc (child);
2569 if (handle_extended_wait (&child, wstat))
2571 /* The event has been handled, so just return without
2577 if (linux_wstatus_maybe_breakpoint (wstat))
2579 if (save_stop_reason (child))
2584 child->stop_pc = get_pc (child);
2586 if (WIFSTOPPED (wstat) && WSTOPSIG (wstat) == SIGSTOP
2587 && child->stop_expected)
2590 debug_printf ("Expected stop.\n");
2591 child->stop_expected = 0;
2593 if (thread->last_resume_kind == resume_stop)
2595 /* We want to report the stop to the core. Treat the
2596 SIGSTOP as a normal event. */
2598 debug_printf ("LLW: resume_stop SIGSTOP caught for %s.\n",
2599 target_pid_to_str (ptid_of (thread)));
2601 else if (stopping_threads != NOT_STOPPING_THREADS)
2603 /* Stopping threads. We don't want this SIGSTOP to end up
2606 debug_printf ("LLW: SIGSTOP caught for %s "
2607 "while stopping threads.\n",
2608 target_pid_to_str (ptid_of (thread)));
2613 /* This is a delayed SIGSTOP. Filter out the event. */
2615 debug_printf ("LLW: %s %s, 0, 0 (discard delayed SIGSTOP)\n",
2616 child->stepping ? "step" : "continue",
2617 target_pid_to_str (ptid_of (thread)));
2619 linux_resume_one_lwp (child, child->stepping, 0, NULL);
2624 child->status_pending_p = 1;
2625 child->status_pending = wstat;
2629 /* Return true if THREAD is doing hardware single step. */
2632 maybe_hw_step (struct thread_info *thread)
2634 if (can_hardware_single_step ())
2638 /* GDBserver must insert single-step breakpoint for software
2640 gdb_assert (has_single_step_breakpoints (thread));
2645 /* Resume LWPs that are currently stopped without any pending status
2646 to report, but are resumed from the core's perspective. */
2649 resume_stopped_resumed_lwps (struct inferior_list_entry *entry)
2651 struct thread_info *thread = (struct thread_info *) entry;
2652 struct lwp_info *lp = get_thread_lwp (thread);
2656 && !lp->status_pending_p
2657 && thread->last_status.kind == TARGET_WAITKIND_IGNORE)
2661 if (thread->last_resume_kind == resume_step)
2662 step = maybe_hw_step (thread);
2665 debug_printf ("RSRL: resuming stopped-resumed LWP %s at %s: step=%d\n",
2666 target_pid_to_str (ptid_of (thread)),
2667 paddress (lp->stop_pc),
2670 linux_resume_one_lwp (lp, step, GDB_SIGNAL_0, NULL);
2674 /* Wait for an event from child(ren) WAIT_PTID, and return any that
2675 match FILTER_PTID (leaving others pending). The PTIDs can be:
2676 minus_one_ptid, to specify any child; a pid PTID, specifying all
2677 lwps of a thread group; or a PTID representing a single lwp. Store
2678 the stop status through the status pointer WSTAT. OPTIONS is
2679 passed to the waitpid call. Return 0 if no event was found and
2680 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
2681 was found. Return the PID of the stopped child otherwise. */
2684 linux_wait_for_event_filtered (ptid_t wait_ptid, ptid_t filter_ptid,
2685 int *wstatp, int options)
2687 struct thread_info *event_thread;
2688 struct lwp_info *event_child, *requested_child;
2689 sigset_t block_mask, prev_mask;
2692 /* N.B. event_thread points to the thread_info struct that contains
2693 event_child. Keep them in sync. */
2694 event_thread = NULL;
2696 requested_child = NULL;
2698 /* Check for a lwp with a pending status. */
2700 if (ptid_equal (filter_ptid, minus_one_ptid) || ptid_is_pid (filter_ptid))
2702 event_thread = (struct thread_info *)
2703 find_inferior_in_random (&all_threads, status_pending_p_callback,
2705 if (event_thread != NULL)
2706 event_child = get_thread_lwp (event_thread);
2707 if (debug_threads && event_thread)
2708 debug_printf ("Got a pending child %ld\n", lwpid_of (event_thread));
2710 else if (!ptid_equal (filter_ptid, null_ptid))
2712 requested_child = find_lwp_pid (filter_ptid);
2714 if (stopping_threads == NOT_STOPPING_THREADS
2715 && requested_child->status_pending_p
2716 && requested_child->collecting_fast_tracepoint)
2718 enqueue_one_deferred_signal (requested_child,
2719 &requested_child->status_pending);
2720 requested_child->status_pending_p = 0;
2721 requested_child->status_pending = 0;
2722 linux_resume_one_lwp (requested_child, 0, 0, NULL);
2725 if (requested_child->suspended
2726 && requested_child->status_pending_p)
2728 internal_error (__FILE__, __LINE__,
2729 "requesting an event out of a"
2730 " suspended child?");
2733 if (requested_child->status_pending_p)
2735 event_child = requested_child;
2736 event_thread = get_lwp_thread (event_child);
2740 if (event_child != NULL)
2743 debug_printf ("Got an event from pending child %ld (%04x)\n",
2744 lwpid_of (event_thread), event_child->status_pending);
2745 *wstatp = event_child->status_pending;
2746 event_child->status_pending_p = 0;
2747 event_child->status_pending = 0;
2748 current_thread = event_thread;
2749 return lwpid_of (event_thread);
2752 /* But if we don't find a pending event, we'll have to wait.
2754 We only enter this loop if no process has a pending wait status.
2755 Thus any action taken in response to a wait status inside this
2756 loop is responding as soon as we detect the status, not after any
2759 /* Make sure SIGCHLD is blocked until the sigsuspend below. Block
2760 all signals while here. */
2761 sigfillset (&block_mask);
2762 sigprocmask (SIG_BLOCK, &block_mask, &prev_mask);
2764 /* Always pull all events out of the kernel. We'll randomly select
2765 an event LWP out of all that have events, to prevent
2767 while (event_child == NULL)
2771 /* Always use -1 and WNOHANG, due to couple of a kernel/ptrace
2774 - If the thread group leader exits while other threads in the
2775 thread group still exist, waitpid(TGID, ...) hangs. That
2776 waitpid won't return an exit status until the other threads
2777 in the group are reaped.
2779 - When a non-leader thread execs, that thread just vanishes
2780 without reporting an exit (so we'd hang if we waited for it
2781 explicitly in that case). The exec event is reported to
2784 ret = my_waitpid (-1, wstatp, options | WNOHANG);
2787 debug_printf ("LWFE: waitpid(-1, ...) returned %d, %s\n",
2788 ret, errno ? strerror (errno) : "ERRNO-OK");
2794 debug_printf ("LLW: waitpid %ld received %s\n",
2795 (long) ret, status_to_str (*wstatp));
2798 /* Filter all events. IOW, leave all events pending. We'll
2799 randomly select an event LWP out of all that have events
2801 linux_low_filter_event (ret, *wstatp);
2802 /* Retry until nothing comes out of waitpid. A single
2803 SIGCHLD can indicate more than one child stopped. */
2807 /* Now that we've pulled all events out of the kernel, resume
2808 LWPs that don't have an interesting event to report. */
2809 if (stopping_threads == NOT_STOPPING_THREADS)
2810 for_each_inferior (&all_threads, resume_stopped_resumed_lwps);
2812 /* ... and find an LWP with a status to report to the core, if
2814 event_thread = (struct thread_info *)
2815 find_inferior_in_random (&all_threads, status_pending_p_callback,
2817 if (event_thread != NULL)
2819 event_child = get_thread_lwp (event_thread);
2820 *wstatp = event_child->status_pending;
2821 event_child->status_pending_p = 0;
2822 event_child->status_pending = 0;
2826 /* Check for zombie thread group leaders. Those can't be reaped
2827 until all other threads in the thread group are. */
2828 check_zombie_leaders ();
2830 /* If there are no resumed children left in the set of LWPs we
2831 want to wait for, bail. We can't just block in
2832 waitpid/sigsuspend, because lwps might have been left stopped
2833 in trace-stop state, and we'd be stuck forever waiting for
2834 their status to change (which would only happen if we resumed
2835 them). Even if WNOHANG is set, this return code is preferred
2836 over 0 (below), as it is more detailed. */
2837 if ((find_inferior (&all_threads,
2838 not_stopped_callback,
2839 &wait_ptid) == NULL))
2842 debug_printf ("LLW: exit (no unwaited-for LWP)\n");
2843 sigprocmask (SIG_SETMASK, &prev_mask, NULL);
2847 /* No interesting event to report to the caller. */
2848 if ((options & WNOHANG))
2851 debug_printf ("WNOHANG set, no event found\n");
2853 sigprocmask (SIG_SETMASK, &prev_mask, NULL);
2857 /* Block until we get an event reported with SIGCHLD. */
2859 debug_printf ("sigsuspend'ing\n");
2861 sigsuspend (&prev_mask);
2862 sigprocmask (SIG_SETMASK, &prev_mask, NULL);
2866 sigprocmask (SIG_SETMASK, &prev_mask, NULL);
2868 current_thread = event_thread;
2870 return lwpid_of (event_thread);
2873 /* Wait for an event from child(ren) PTID. PTIDs can be:
2874 minus_one_ptid, to specify any child; a pid PTID, specifying all
2875 lwps of a thread group; or a PTID representing a single lwp. Store
2876 the stop status through the status pointer WSTAT. OPTIONS is
2877 passed to the waitpid call. Return 0 if no event was found and
2878 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
2879 was found. Return the PID of the stopped child otherwise. */
2882 linux_wait_for_event (ptid_t ptid, int *wstatp, int options)
2884 return linux_wait_for_event_filtered (ptid, ptid, wstatp, options);
2887 /* Count the LWP's that have had events. */
2890 count_events_callback (struct inferior_list_entry *entry, void *data)
2892 struct thread_info *thread = (struct thread_info *) entry;
2893 struct lwp_info *lp = get_thread_lwp (thread);
2894 int *count = (int *) data;
2896 gdb_assert (count != NULL);
2898 /* Count only resumed LWPs that have an event pending. */
2899 if (thread->last_status.kind == TARGET_WAITKIND_IGNORE
2900 && lp->status_pending_p)
2906 /* Select the LWP (if any) that is currently being single-stepped. */
2909 select_singlestep_lwp_callback (struct inferior_list_entry *entry, void *data)
2911 struct thread_info *thread = (struct thread_info *) entry;
2912 struct lwp_info *lp = get_thread_lwp (thread);
2914 if (thread->last_status.kind == TARGET_WAITKIND_IGNORE
2915 && thread->last_resume_kind == resume_step
2916 && lp->status_pending_p)
2922 /* Select the Nth LWP that has had an event. */
2925 select_event_lwp_callback (struct inferior_list_entry *entry, void *data)
2927 struct thread_info *thread = (struct thread_info *) entry;
2928 struct lwp_info *lp = get_thread_lwp (thread);
2929 int *selector = (int *) data;
2931 gdb_assert (selector != NULL);
2933 /* Select only resumed LWPs that have an event pending. */
2934 if (thread->last_status.kind == TARGET_WAITKIND_IGNORE
2935 && lp->status_pending_p)
2936 if ((*selector)-- == 0)
2942 /* Select one LWP out of those that have events pending. */
2945 select_event_lwp (struct lwp_info **orig_lp)
2948 int random_selector;
2949 struct thread_info *event_thread = NULL;
2951 /* In all-stop, give preference to the LWP that is being
2952 single-stepped. There will be at most one, and it's the LWP that
2953 the core is most interested in. If we didn't do this, then we'd
2954 have to handle pending step SIGTRAPs somehow in case the core
2955 later continues the previously-stepped thread, otherwise we'd
2956 report the pending SIGTRAP, and the core, not having stepped the
2957 thread, wouldn't understand what the trap was for, and therefore
2958 would report it to the user as a random signal. */
2962 = (struct thread_info *) find_inferior (&all_threads,
2963 select_singlestep_lwp_callback,
2965 if (event_thread != NULL)
2968 debug_printf ("SEL: Select single-step %s\n",
2969 target_pid_to_str (ptid_of (event_thread)));
2972 if (event_thread == NULL)
2974 /* No single-stepping LWP. Select one at random, out of those
2975 which have had events. */
2977 /* First see how many events we have. */
2978 find_inferior (&all_threads, count_events_callback, &num_events);
2979 gdb_assert (num_events > 0);
2981 /* Now randomly pick a LWP out of those that have had
2983 random_selector = (int)
2984 ((num_events * (double) rand ()) / (RAND_MAX + 1.0));
2986 if (debug_threads && num_events > 1)
2987 debug_printf ("SEL: Found %d SIGTRAP events, selecting #%d\n",
2988 num_events, random_selector);
2991 = (struct thread_info *) find_inferior (&all_threads,
2992 select_event_lwp_callback,
2996 if (event_thread != NULL)
2998 struct lwp_info *event_lp = get_thread_lwp (event_thread);
3000 /* Switch the event LWP. */
3001 *orig_lp = event_lp;
3005 /* Decrement the suspend count of an LWP. */
3008 unsuspend_one_lwp (struct inferior_list_entry *entry, void *except)
3010 struct thread_info *thread = (struct thread_info *) entry;
3011 struct lwp_info *lwp = get_thread_lwp (thread);
3013 /* Ignore EXCEPT. */
3017 lwp_suspended_decr (lwp);
3021 /* Decrement the suspend count of all LWPs, except EXCEPT, if non
3025 unsuspend_all_lwps (struct lwp_info *except)
3027 find_inferior (&all_threads, unsuspend_one_lwp, except);
3030 static void move_out_of_jump_pad_callback (struct inferior_list_entry *entry);
3031 static int stuck_in_jump_pad_callback (struct inferior_list_entry *entry,
3033 static int lwp_running (struct inferior_list_entry *entry, void *data);
3034 static ptid_t linux_wait_1 (ptid_t ptid,
3035 struct target_waitstatus *ourstatus,
3036 int target_options);
3038 /* Stabilize threads (move out of jump pads).
3040 If a thread is midway collecting a fast tracepoint, we need to
3041 finish the collection and move it out of the jump pad before
3042 reporting the signal.
3044 This avoids recursion while collecting (when a signal arrives
3045 midway, and the signal handler itself collects), which would trash
3046 the trace buffer. In case the user set a breakpoint in a signal
3047 handler, this avoids the backtrace showing the jump pad, etc..
3048 Most importantly, there are certain things we can't do safely if
3049 threads are stopped in a jump pad (or in its callee's). For
3052 - starting a new trace run. A thread still collecting the
3053 previous run, could trash the trace buffer when resumed. The trace
3054 buffer control structures would have been reset but the thread had
3055 no way to tell. The thread could even midway memcpy'ing to the
3056 buffer, which would mean that when resumed, it would clobber the
3057 trace buffer that had been set for a new run.
3059 - we can't rewrite/reuse the jump pads for new tracepoints
3060 safely. Say you do tstart while a thread is stopped midway while
3061 collecting. When the thread is later resumed, it finishes the
3062 collection, and returns to the jump pad, to execute the original
3063 instruction that was under the tracepoint jump at the time the
3064 older run had been started. If the jump pad had been rewritten
3065 since for something else in the new run, the thread would now
3066 execute the wrong / random instructions. */
3069 linux_stabilize_threads (void)
3071 struct thread_info *saved_thread;
3072 struct thread_info *thread_stuck;
3075 = (struct thread_info *) find_inferior (&all_threads,
3076 stuck_in_jump_pad_callback,
3078 if (thread_stuck != NULL)
3081 debug_printf ("can't stabilize, LWP %ld is stuck in jump pad\n",
3082 lwpid_of (thread_stuck));
3086 saved_thread = current_thread;
3088 stabilizing_threads = 1;
3091 for_each_inferior (&all_threads, move_out_of_jump_pad_callback);
3093 /* Loop until all are stopped out of the jump pads. */
3094 while (find_inferior (&all_threads, lwp_running, NULL) != NULL)
3096 struct target_waitstatus ourstatus;
3097 struct lwp_info *lwp;
3100 /* Note that we go through the full wait even loop. While
3101 moving threads out of jump pad, we need to be able to step
3102 over internal breakpoints and such. */
3103 linux_wait_1 (minus_one_ptid, &ourstatus, 0);
3105 if (ourstatus.kind == TARGET_WAITKIND_STOPPED)
3107 lwp = get_thread_lwp (current_thread);
3110 lwp_suspended_inc (lwp);
3112 if (ourstatus.value.sig != GDB_SIGNAL_0
3113 || current_thread->last_resume_kind == resume_stop)
3115 wstat = W_STOPCODE (gdb_signal_to_host (ourstatus.value.sig));
3116 enqueue_one_deferred_signal (lwp, &wstat);
3121 unsuspend_all_lwps (NULL);
3123 stabilizing_threads = 0;
3125 current_thread = saved_thread;
3130 = (struct thread_info *) find_inferior (&all_threads,
3131 stuck_in_jump_pad_callback,
3133 if (thread_stuck != NULL)
3134 debug_printf ("couldn't stabilize, LWP %ld got stuck in jump pad\n",
3135 lwpid_of (thread_stuck));
3139 /* Convenience function that is called when the kernel reports an
3140 event that is not passed out to GDB. */
3143 ignore_event (struct target_waitstatus *ourstatus)
3145 /* If we got an event, there may still be others, as a single
3146 SIGCHLD can indicate more than one child stopped. This forces
3147 another target_wait call. */
3150 ourstatus->kind = TARGET_WAITKIND_IGNORE;
3154 /* Convenience function that is called when the kernel reports an exit
3155 event. This decides whether to report the event to GDB as a
3156 process exit event, a thread exit event, or to suppress the
3160 filter_exit_event (struct lwp_info *event_child,
3161 struct target_waitstatus *ourstatus)
3163 struct thread_info *thread = get_lwp_thread (event_child);
3164 ptid_t ptid = ptid_of (thread);
3166 if (!last_thread_of_process_p (pid_of (thread)))
3168 if (report_thread_events)
3169 ourstatus->kind = TARGET_WAITKIND_THREAD_EXITED;
3171 ourstatus->kind = TARGET_WAITKIND_IGNORE;
3173 delete_lwp (event_child);
3178 /* Returns 1 if GDB is interested in any event_child syscalls. */
3181 gdb_catching_syscalls_p (struct lwp_info *event_child)
3183 struct thread_info *thread = get_lwp_thread (event_child);
3184 struct process_info *proc = get_thread_process (thread);
3186 return !VEC_empty (int, proc->syscalls_to_catch);
3189 /* Returns 1 if GDB is interested in the event_child syscall.
3190 Only to be called when stopped reason is SYSCALL_SIGTRAP. */
3193 gdb_catch_this_syscall_p (struct lwp_info *event_child)
3197 struct thread_info *thread = get_lwp_thread (event_child);
3198 struct process_info *proc = get_thread_process (thread);
3200 if (VEC_empty (int, proc->syscalls_to_catch))
3203 if (VEC_index (int, proc->syscalls_to_catch, 0) == ANY_SYSCALL)
3206 get_syscall_trapinfo (event_child, &sysno);
3208 VEC_iterate (int, proc->syscalls_to_catch, i, iter);
3216 /* Wait for process, returns status. */
3219 linux_wait_1 (ptid_t ptid,
3220 struct target_waitstatus *ourstatus, int target_options)
3223 struct lwp_info *event_child;
3226 int step_over_finished;
3227 int bp_explains_trap;
3228 int maybe_internal_trap;
3237 debug_printf ("linux_wait_1: [%s]\n", target_pid_to_str (ptid));
3240 /* Translate generic target options into linux options. */
3242 if (target_options & TARGET_WNOHANG)
3245 bp_explains_trap = 0;
3248 ourstatus->kind = TARGET_WAITKIND_IGNORE;
3250 /* Find a resumed LWP, if any. */
3251 if (find_inferior (&all_threads,
3252 status_pending_p_callback,
3253 &minus_one_ptid) != NULL)
3255 else if ((find_inferior (&all_threads,
3256 not_stopped_callback,
3257 &minus_one_ptid) != NULL))
3262 if (ptid_equal (step_over_bkpt, null_ptid))
3263 pid = linux_wait_for_event (ptid, &w, options);
3267 debug_printf ("step_over_bkpt set [%s], doing a blocking wait\n",
3268 target_pid_to_str (step_over_bkpt));
3269 pid = linux_wait_for_event (step_over_bkpt, &w, options & ~WNOHANG);
3272 if (pid == 0 || (pid == -1 && !any_resumed))
3274 gdb_assert (target_options & TARGET_WNOHANG);
3278 debug_printf ("linux_wait_1 ret = null_ptid, "
3279 "TARGET_WAITKIND_IGNORE\n");
3283 ourstatus->kind = TARGET_WAITKIND_IGNORE;
3290 debug_printf ("linux_wait_1 ret = null_ptid, "
3291 "TARGET_WAITKIND_NO_RESUMED\n");
3295 ourstatus->kind = TARGET_WAITKIND_NO_RESUMED;
3299 event_child = get_thread_lwp (current_thread);
3301 /* linux_wait_for_event only returns an exit status for the last
3302 child of a process. Report it. */
3303 if (WIFEXITED (w) || WIFSIGNALED (w))
3307 ourstatus->kind = TARGET_WAITKIND_EXITED;
3308 ourstatus->value.integer = WEXITSTATUS (w);
3312 debug_printf ("linux_wait_1 ret = %s, exited with "
3314 target_pid_to_str (ptid_of (current_thread)),
3321 ourstatus->kind = TARGET_WAITKIND_SIGNALLED;
3322 ourstatus->value.sig = gdb_signal_from_host (WTERMSIG (w));
3326 debug_printf ("linux_wait_1 ret = %s, terminated with "
3328 target_pid_to_str (ptid_of (current_thread)),
3334 if (ourstatus->kind == TARGET_WAITKIND_EXITED)
3335 return filter_exit_event (event_child, ourstatus);
3337 return ptid_of (current_thread);
3340 /* If step-over executes a breakpoint instruction, in the case of a
3341 hardware single step it means a gdb/gdbserver breakpoint had been
3342 planted on top of a permanent breakpoint, in the case of a software
3343 single step it may just mean that gdbserver hit the reinsert breakpoint.
3344 The PC has been adjusted by save_stop_reason to point at
3345 the breakpoint address.
3346 So in the case of the hardware single step advance the PC manually
3347 past the breakpoint and in the case of software single step advance only
3348 if it's not the single_step_breakpoint we are hitting.
3349 This avoids that a program would keep trapping a permanent breakpoint
3351 if (!ptid_equal (step_over_bkpt, null_ptid)
3352 && event_child->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT
3353 && (event_child->stepping
3354 || !single_step_breakpoint_inserted_here (event_child->stop_pc)))
3356 int increment_pc = 0;
3357 int breakpoint_kind = 0;
3358 CORE_ADDR stop_pc = event_child->stop_pc;
3361 the_target->breakpoint_kind_from_current_state (&stop_pc);
3362 the_target->sw_breakpoint_from_kind (breakpoint_kind, &increment_pc);
3366 debug_printf ("step-over for %s executed software breakpoint\n",
3367 target_pid_to_str (ptid_of (current_thread)));
3370 if (increment_pc != 0)
3372 struct regcache *regcache
3373 = get_thread_regcache (current_thread, 1);
3375 event_child->stop_pc += increment_pc;
3376 (*the_low_target.set_pc) (regcache, event_child->stop_pc);
3378 if (!(*the_low_target.breakpoint_at) (event_child->stop_pc))
3379 event_child->stop_reason = TARGET_STOPPED_BY_NO_REASON;
3383 /* If this event was not handled before, and is not a SIGTRAP, we
3384 report it. SIGILL and SIGSEGV are also treated as traps in case
3385 a breakpoint is inserted at the current PC. If this target does
3386 not support internal breakpoints at all, we also report the
3387 SIGTRAP without further processing; it's of no concern to us. */
3389 = (supports_breakpoints ()
3390 && (WSTOPSIG (w) == SIGTRAP
3391 || ((WSTOPSIG (w) == SIGILL
3392 || WSTOPSIG (w) == SIGSEGV)
3393 && (*the_low_target.breakpoint_at) (event_child->stop_pc))));
3395 if (maybe_internal_trap)
3397 /* Handle anything that requires bookkeeping before deciding to
3398 report the event or continue waiting. */
3400 /* First check if we can explain the SIGTRAP with an internal
3401 breakpoint, or if we should possibly report the event to GDB.
3402 Do this before anything that may remove or insert a
3404 bp_explains_trap = breakpoint_inserted_here (event_child->stop_pc);
3406 /* We have a SIGTRAP, possibly a step-over dance has just
3407 finished. If so, tweak the state machine accordingly,
3408 reinsert breakpoints and delete any single-step
3410 step_over_finished = finish_step_over (event_child);
3412 /* Now invoke the callbacks of any internal breakpoints there. */
3413 check_breakpoints (event_child->stop_pc);
3415 /* Handle tracepoint data collecting. This may overflow the
3416 trace buffer, and cause a tracing stop, removing
3418 trace_event = handle_tracepoints (event_child);
3420 if (bp_explains_trap)
3423 debug_printf ("Hit a gdbserver breakpoint.\n");
3428 /* We have some other signal, possibly a step-over dance was in
3429 progress, and it should be cancelled too. */
3430 step_over_finished = finish_step_over (event_child);
3433 /* We have all the data we need. Either report the event to GDB, or
3434 resume threads and keep waiting for more. */
3436 /* If we're collecting a fast tracepoint, finish the collection and
3437 move out of the jump pad before delivering a signal. See
3438 linux_stabilize_threads. */
3441 && WSTOPSIG (w) != SIGTRAP
3442 && supports_fast_tracepoints ()
3443 && agent_loaded_p ())
3446 debug_printf ("Got signal %d for LWP %ld. Check if we need "
3447 "to defer or adjust it.\n",
3448 WSTOPSIG (w), lwpid_of (current_thread));
3450 /* Allow debugging the jump pad itself. */
3451 if (current_thread->last_resume_kind != resume_step
3452 && maybe_move_out_of_jump_pad (event_child, &w))
3454 enqueue_one_deferred_signal (event_child, &w);
3457 debug_printf ("Signal %d for LWP %ld deferred (in jump pad)\n",
3458 WSTOPSIG (w), lwpid_of (current_thread));
3460 linux_resume_one_lwp (event_child, 0, 0, NULL);
3464 return ignore_event (ourstatus);
3468 if (event_child->collecting_fast_tracepoint)
3471 debug_printf ("LWP %ld was trying to move out of the jump pad (%d). "
3472 "Check if we're already there.\n",
3473 lwpid_of (current_thread),
3474 event_child->collecting_fast_tracepoint);
3478 event_child->collecting_fast_tracepoint
3479 = linux_fast_tracepoint_collecting (event_child, NULL);
3481 if (event_child->collecting_fast_tracepoint != 1)
3483 /* No longer need this breakpoint. */
3484 if (event_child->exit_jump_pad_bkpt != NULL)
3487 debug_printf ("No longer need exit-jump-pad bkpt; removing it."
3488 "stopping all threads momentarily.\n");
3490 /* Other running threads could hit this breakpoint.
3491 We don't handle moribund locations like GDB does,
3492 instead we always pause all threads when removing
3493 breakpoints, so that any step-over or
3494 decr_pc_after_break adjustment is always taken
3495 care of while the breakpoint is still
3497 stop_all_lwps (1, event_child);
3499 delete_breakpoint (event_child->exit_jump_pad_bkpt);
3500 event_child->exit_jump_pad_bkpt = NULL;
3502 unstop_all_lwps (1, event_child);
3504 gdb_assert (event_child->suspended >= 0);
3508 if (event_child->collecting_fast_tracepoint == 0)
3511 debug_printf ("fast tracepoint finished "
3512 "collecting successfully.\n");
3514 /* We may have a deferred signal to report. */
3515 if (dequeue_one_deferred_signal (event_child, &w))
3518 debug_printf ("dequeued one signal.\n");
3523 debug_printf ("no deferred signals.\n");
3525 if (stabilizing_threads)
3527 ourstatus->kind = TARGET_WAITKIND_STOPPED;
3528 ourstatus->value.sig = GDB_SIGNAL_0;
3532 debug_printf ("linux_wait_1 ret = %s, stopped "
3533 "while stabilizing threads\n",
3534 target_pid_to_str (ptid_of (current_thread)));
3538 return ptid_of (current_thread);
3544 /* Check whether GDB would be interested in this event. */
3546 /* Check if GDB is interested in this syscall. */
3548 && WSTOPSIG (w) == SYSCALL_SIGTRAP
3549 && !gdb_catch_this_syscall_p (event_child))
3553 debug_printf ("Ignored syscall for LWP %ld.\n",
3554 lwpid_of (current_thread));
3557 linux_resume_one_lwp (event_child, event_child->stepping,
3562 return ignore_event (ourstatus);
3565 /* If GDB is not interested in this signal, don't stop other
3566 threads, and don't report it to GDB. Just resume the inferior
3567 right away. We do this for threading-related signals as well as
3568 any that GDB specifically requested we ignore. But never ignore
3569 SIGSTOP if we sent it ourselves, and do not ignore signals when
3570 stepping - they may require special handling to skip the signal
3571 handler. Also never ignore signals that could be caused by a
3574 && current_thread->last_resume_kind != resume_step
3576 #if defined (USE_THREAD_DB) && !defined (__ANDROID__)
3577 (current_process ()->priv->thread_db != NULL
3578 && (WSTOPSIG (w) == __SIGRTMIN
3579 || WSTOPSIG (w) == __SIGRTMIN + 1))
3582 (pass_signals[gdb_signal_from_host (WSTOPSIG (w))]
3583 && !(WSTOPSIG (w) == SIGSTOP
3584 && current_thread->last_resume_kind == resume_stop)
3585 && !linux_wstatus_maybe_breakpoint (w))))
3587 siginfo_t info, *info_p;
3590 debug_printf ("Ignored signal %d for LWP %ld.\n",
3591 WSTOPSIG (w), lwpid_of (current_thread));
3593 if (ptrace (PTRACE_GETSIGINFO, lwpid_of (current_thread),
3594 (PTRACE_TYPE_ARG3) 0, &info) == 0)
3599 if (step_over_finished)
3601 /* We cancelled this thread's step-over above. We still
3602 need to unsuspend all other LWPs, and set them back
3603 running again while the signal handler runs. */
3604 unsuspend_all_lwps (event_child);
3606 /* Enqueue the pending signal info so that proceed_all_lwps
3608 enqueue_pending_signal (event_child, WSTOPSIG (w), info_p);
3610 proceed_all_lwps ();
3614 linux_resume_one_lwp (event_child, event_child->stepping,
3615 WSTOPSIG (w), info_p);
3621 return ignore_event (ourstatus);
3624 /* Note that all addresses are always "out of the step range" when
3625 there's no range to begin with. */
3626 in_step_range = lwp_in_step_range (event_child);
3628 /* If GDB wanted this thread to single step, and the thread is out
3629 of the step range, we always want to report the SIGTRAP, and let
3630 GDB handle it. Watchpoints should always be reported. So should
3631 signals we can't explain. A SIGTRAP we can't explain could be a
3632 GDB breakpoint --- we may or not support Z0 breakpoints. If we
3633 do, we're be able to handle GDB breakpoints on top of internal
3634 breakpoints, by handling the internal breakpoint and still
3635 reporting the event to GDB. If we don't, we're out of luck, GDB
3636 won't see the breakpoint hit. If we see a single-step event but
3637 the thread should be continuing, don't pass the trap to gdb.
3638 That indicates that we had previously finished a single-step but
3639 left the single-step pending -- see
3640 complete_ongoing_step_over. */
3641 report_to_gdb = (!maybe_internal_trap
3642 || (current_thread->last_resume_kind == resume_step
3644 || event_child->stop_reason == TARGET_STOPPED_BY_WATCHPOINT
3646 && !bp_explains_trap
3648 && !step_over_finished
3649 && !(current_thread->last_resume_kind == resume_continue
3650 && event_child->stop_reason == TARGET_STOPPED_BY_SINGLE_STEP))
3651 || (gdb_breakpoint_here (event_child->stop_pc)
3652 && gdb_condition_true_at_breakpoint (event_child->stop_pc)
3653 && gdb_no_commands_at_breakpoint (event_child->stop_pc))
3654 || event_child->waitstatus.kind != TARGET_WAITKIND_IGNORE);
3656 run_breakpoint_commands (event_child->stop_pc);
3658 /* We found no reason GDB would want us to stop. We either hit one
3659 of our own breakpoints, or finished an internal step GDB
3660 shouldn't know about. */
3665 if (bp_explains_trap)
3666 debug_printf ("Hit a gdbserver breakpoint.\n");
3667 if (step_over_finished)
3668 debug_printf ("Step-over finished.\n");
3670 debug_printf ("Tracepoint event.\n");
3671 if (lwp_in_step_range (event_child))
3672 debug_printf ("Range stepping pc 0x%s [0x%s, 0x%s).\n",
3673 paddress (event_child->stop_pc),
3674 paddress (event_child->step_range_start),
3675 paddress (event_child->step_range_end));
3678 /* We're not reporting this breakpoint to GDB, so apply the
3679 decr_pc_after_break adjustment to the inferior's regcache
3682 if (the_low_target.set_pc != NULL)
3684 struct regcache *regcache
3685 = get_thread_regcache (current_thread, 1);
3686 (*the_low_target.set_pc) (regcache, event_child->stop_pc);
3689 if (step_over_finished)
3691 /* If we have finished stepping over a breakpoint, we've
3692 stopped and suspended all LWPs momentarily except the
3693 stepping one. This is where we resume them all again.
3694 We're going to keep waiting, so use proceed, which
3695 handles stepping over the next breakpoint. */
3696 unsuspend_all_lwps (event_child);
3700 /* Remove the single-step breakpoints if any. Note that
3701 there isn't single-step breakpoint if we finished stepping
3703 if (can_software_single_step ()
3704 && has_single_step_breakpoints (current_thread))
3706 stop_all_lwps (0, event_child);
3707 delete_single_step_breakpoints (current_thread);
3708 unstop_all_lwps (0, event_child);
3713 debug_printf ("proceeding all threads.\n");
3714 proceed_all_lwps ();
3719 return ignore_event (ourstatus);
3724 if (event_child->waitstatus.kind != TARGET_WAITKIND_IGNORE)
3728 str = target_waitstatus_to_string (&event_child->waitstatus);
3729 debug_printf ("LWP %ld: extended event with waitstatus %s\n",
3730 lwpid_of (get_lwp_thread (event_child)), str);
3733 if (current_thread->last_resume_kind == resume_step)
3735 if (event_child->step_range_start == event_child->step_range_end)
3736 debug_printf ("GDB wanted to single-step, reporting event.\n");
3737 else if (!lwp_in_step_range (event_child))
3738 debug_printf ("Out of step range, reporting event.\n");
3740 if (event_child->stop_reason == TARGET_STOPPED_BY_WATCHPOINT)
3741 debug_printf ("Stopped by watchpoint.\n");
3742 else if (gdb_breakpoint_here (event_child->stop_pc))
3743 debug_printf ("Stopped by GDB breakpoint.\n");
3745 debug_printf ("Hit a non-gdbserver trap event.\n");
3748 /* Alright, we're going to report a stop. */
3750 /* Remove single-step breakpoints. */
3751 if (can_software_single_step ())
3753 /* Remove single-step breakpoints or not. It it is true, stop all
3754 lwps, so that other threads won't hit the breakpoint in the
3756 int remove_single_step_breakpoints_p = 0;
3760 remove_single_step_breakpoints_p
3761 = has_single_step_breakpoints (current_thread);
3765 /* In all-stop, a stop reply cancels all previous resume
3766 requests. Delete all single-step breakpoints. */
3767 struct inferior_list_entry *inf, *tmp;
3769 ALL_INFERIORS (&all_threads, inf, tmp)
3771 struct thread_info *thread = (struct thread_info *) inf;
3773 if (has_single_step_breakpoints (thread))
3775 remove_single_step_breakpoints_p = 1;
3781 if (remove_single_step_breakpoints_p)
3783 /* If we remove single-step breakpoints from memory, stop all lwps,
3784 so that other threads won't hit the breakpoint in the staled
3786 stop_all_lwps (0, event_child);
3790 gdb_assert (has_single_step_breakpoints (current_thread));
3791 delete_single_step_breakpoints (current_thread);
3795 struct inferior_list_entry *inf, *tmp;
3797 ALL_INFERIORS (&all_threads, inf, tmp)
3799 struct thread_info *thread = (struct thread_info *) inf;
3801 if (has_single_step_breakpoints (thread))
3802 delete_single_step_breakpoints (thread);
3806 unstop_all_lwps (0, event_child);
3810 if (!stabilizing_threads)
3812 /* In all-stop, stop all threads. */
3814 stop_all_lwps (0, NULL);
3816 if (step_over_finished)
3820 /* If we were doing a step-over, all other threads but
3821 the stepping one had been paused in start_step_over,
3822 with their suspend counts incremented. We don't want
3823 to do a full unstop/unpause, because we're in
3824 all-stop mode (so we want threads stopped), but we
3825 still need to unsuspend the other threads, to
3826 decrement their `suspended' count back. */
3827 unsuspend_all_lwps (event_child);
3831 /* If we just finished a step-over, then all threads had
3832 been momentarily paused. In all-stop, that's fine,
3833 we want threads stopped by now anyway. In non-stop,
3834 we need to re-resume threads that GDB wanted to be
3836 unstop_all_lwps (1, event_child);
3840 /* If we're not waiting for a specific LWP, choose an event LWP
3841 from among those that have had events. Giving equal priority
3842 to all LWPs that have had events helps prevent
3844 if (ptid_equal (ptid, minus_one_ptid))
3846 event_child->status_pending_p = 1;
3847 event_child->status_pending = w;
3849 select_event_lwp (&event_child);
3851 /* current_thread and event_child must stay in sync. */
3852 current_thread = get_lwp_thread (event_child);
3854 event_child->status_pending_p = 0;
3855 w = event_child->status_pending;
3859 /* Stabilize threads (move out of jump pads). */
3861 stabilize_threads ();
3865 /* If we just finished a step-over, then all threads had been
3866 momentarily paused. In all-stop, that's fine, we want
3867 threads stopped by now anyway. In non-stop, we need to
3868 re-resume threads that GDB wanted to be running. */
3869 if (step_over_finished)
3870 unstop_all_lwps (1, event_child);
3873 if (event_child->waitstatus.kind != TARGET_WAITKIND_IGNORE)
3875 /* If the reported event is an exit, fork, vfork or exec, let
3878 /* Break the unreported fork relationship chain. */
3879 if (event_child->waitstatus.kind == TARGET_WAITKIND_FORKED
3880 || event_child->waitstatus.kind == TARGET_WAITKIND_VFORKED)
3882 event_child->fork_relative->fork_relative = NULL;
3883 event_child->fork_relative = NULL;
3886 *ourstatus = event_child->waitstatus;
3887 /* Clear the event lwp's waitstatus since we handled it already. */
3888 event_child->waitstatus.kind = TARGET_WAITKIND_IGNORE;
3891 ourstatus->kind = TARGET_WAITKIND_STOPPED;
3893 /* Now that we've selected our final event LWP, un-adjust its PC if
3894 it was a software breakpoint, and the client doesn't know we can
3895 adjust the breakpoint ourselves. */
3896 if (event_child->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT
3897 && !swbreak_feature)
3899 int decr_pc = the_low_target.decr_pc_after_break;
3903 struct regcache *regcache
3904 = get_thread_regcache (current_thread, 1);
3905 (*the_low_target.set_pc) (regcache, event_child->stop_pc + decr_pc);
3909 if (WSTOPSIG (w) == SYSCALL_SIGTRAP)
3911 get_syscall_trapinfo (event_child,
3912 &ourstatus->value.syscall_number);
3913 ourstatus->kind = event_child->syscall_state;
3915 else if (current_thread->last_resume_kind == resume_stop
3916 && WSTOPSIG (w) == SIGSTOP)
3918 /* A thread that has been requested to stop by GDB with vCont;t,
3919 and it stopped cleanly, so report as SIG0. The use of
3920 SIGSTOP is an implementation detail. */
3921 ourstatus->value.sig = GDB_SIGNAL_0;
3923 else if (current_thread->last_resume_kind == resume_stop
3924 && WSTOPSIG (w) != SIGSTOP)
3926 /* A thread that has been requested to stop by GDB with vCont;t,
3927 but, it stopped for other reasons. */
3928 ourstatus->value.sig = gdb_signal_from_host (WSTOPSIG (w));
3930 else if (ourstatus->kind == TARGET_WAITKIND_STOPPED)
3932 ourstatus->value.sig = gdb_signal_from_host (WSTOPSIG (w));
3935 gdb_assert (ptid_equal (step_over_bkpt, null_ptid));
3939 debug_printf ("linux_wait_1 ret = %s, %d, %d\n",
3940 target_pid_to_str (ptid_of (current_thread)),
3941 ourstatus->kind, ourstatus->value.sig);
3945 if (ourstatus->kind == TARGET_WAITKIND_EXITED)
3946 return filter_exit_event (event_child, ourstatus);
3948 return ptid_of (current_thread);
3951 /* Get rid of any pending event in the pipe. */
3953 async_file_flush (void)
3959 ret = read (linux_event_pipe[0], &buf, 1);
3960 while (ret >= 0 || (ret == -1 && errno == EINTR));
3963 /* Put something in the pipe, so the event loop wakes up. */
3965 async_file_mark (void)
3969 async_file_flush ();
3972 ret = write (linux_event_pipe[1], "+", 1);
3973 while (ret == 0 || (ret == -1 && errno == EINTR));
3975 /* Ignore EAGAIN. If the pipe is full, the event loop will already
3976 be awakened anyway. */
3980 linux_wait (ptid_t ptid,
3981 struct target_waitstatus *ourstatus, int target_options)
3985 /* Flush the async file first. */
3986 if (target_is_async_p ())
3987 async_file_flush ();
3991 event_ptid = linux_wait_1 (ptid, ourstatus, target_options);
3993 while ((target_options & TARGET_WNOHANG) == 0
3994 && ptid_equal (event_ptid, null_ptid)
3995 && ourstatus->kind == TARGET_WAITKIND_IGNORE);
3997 /* If at least one stop was reported, there may be more. A single
3998 SIGCHLD can signal more than one child stop. */
3999 if (target_is_async_p ()
4000 && (target_options & TARGET_WNOHANG) != 0
4001 && !ptid_equal (event_ptid, null_ptid))
4007 /* Send a signal to an LWP. */
4010 kill_lwp (unsigned long lwpid, int signo)
4015 ret = syscall (__NR_tkill, lwpid, signo);
4016 if (errno == ENOSYS)
4018 /* If tkill fails, then we are not using nptl threads, a
4019 configuration we no longer support. */
4020 perror_with_name (("tkill"));
4026 linux_stop_lwp (struct lwp_info *lwp)
4032 send_sigstop (struct lwp_info *lwp)
4036 pid = lwpid_of (get_lwp_thread (lwp));
4038 /* If we already have a pending stop signal for this process, don't
4040 if (lwp->stop_expected)
4043 debug_printf ("Have pending sigstop for lwp %d\n", pid);
4049 debug_printf ("Sending sigstop to lwp %d\n", pid);
4051 lwp->stop_expected = 1;
4052 kill_lwp (pid, SIGSTOP);
4056 send_sigstop_callback (struct inferior_list_entry *entry, void *except)
4058 struct thread_info *thread = (struct thread_info *) entry;
4059 struct lwp_info *lwp = get_thread_lwp (thread);
4061 /* Ignore EXCEPT. */
4072 /* Increment the suspend count of an LWP, and stop it, if not stopped
4075 suspend_and_send_sigstop_callback (struct inferior_list_entry *entry,
4078 struct thread_info *thread = (struct thread_info *) entry;
4079 struct lwp_info *lwp = get_thread_lwp (thread);
4081 /* Ignore EXCEPT. */
4085 lwp_suspended_inc (lwp);
4087 return send_sigstop_callback (entry, except);
4091 mark_lwp_dead (struct lwp_info *lwp, int wstat)
4093 /* Store the exit status for later. */
4094 lwp->status_pending_p = 1;
4095 lwp->status_pending = wstat;
4097 /* Store in waitstatus as well, as there's nothing else to process
4099 if (WIFEXITED (wstat))
4101 lwp->waitstatus.kind = TARGET_WAITKIND_EXITED;
4102 lwp->waitstatus.value.integer = WEXITSTATUS (wstat);
4104 else if (WIFSIGNALED (wstat))
4106 lwp->waitstatus.kind = TARGET_WAITKIND_SIGNALLED;
4107 lwp->waitstatus.value.sig = gdb_signal_from_host (WTERMSIG (wstat));
4110 /* Prevent trying to stop it. */
4113 /* No further stops are expected from a dead lwp. */
4114 lwp->stop_expected = 0;
4117 /* Return true if LWP has exited already, and has a pending exit event
4118 to report to GDB. */
4121 lwp_is_marked_dead (struct lwp_info *lwp)
4123 return (lwp->status_pending_p
4124 && (WIFEXITED (lwp->status_pending)
4125 || WIFSIGNALED (lwp->status_pending)));
4128 /* Wait for all children to stop for the SIGSTOPs we just queued. */
4131 wait_for_sigstop (void)
4133 struct thread_info *saved_thread;
4138 saved_thread = current_thread;
4139 if (saved_thread != NULL)
4140 saved_tid = saved_thread->entry.id;
4142 saved_tid = null_ptid; /* avoid bogus unused warning */
4145 debug_printf ("wait_for_sigstop: pulling events\n");
4147 /* Passing NULL_PTID as filter indicates we want all events to be
4148 left pending. Eventually this returns when there are no
4149 unwaited-for children left. */
4150 ret = linux_wait_for_event_filtered (minus_one_ptid, null_ptid,
4152 gdb_assert (ret == -1);
4154 if (saved_thread == NULL || linux_thread_alive (saved_tid))
4155 current_thread = saved_thread;
4159 debug_printf ("Previously current thread died.\n");
4161 /* We can't change the current inferior behind GDB's back,
4162 otherwise, a subsequent command may apply to the wrong
4164 current_thread = NULL;
4168 /* Returns true if LWP ENTRY is stopped in a jump pad, and we can't
4169 move it out, because we need to report the stop event to GDB. For
4170 example, if the user puts a breakpoint in the jump pad, it's
4171 because she wants to debug it. */
4174 stuck_in_jump_pad_callback (struct inferior_list_entry *entry, void *data)
4176 struct thread_info *thread = (struct thread_info *) entry;
4177 struct lwp_info *lwp = get_thread_lwp (thread);
4179 if (lwp->suspended != 0)
4181 internal_error (__FILE__, __LINE__,
4182 "LWP %ld is suspended, suspended=%d\n",
4183 lwpid_of (thread), lwp->suspended);
4185 gdb_assert (lwp->stopped);
4187 /* Allow debugging the jump pad, gdb_collect, etc.. */
4188 return (supports_fast_tracepoints ()
4189 && agent_loaded_p ()
4190 && (gdb_breakpoint_here (lwp->stop_pc)
4191 || lwp->stop_reason == TARGET_STOPPED_BY_WATCHPOINT
4192 || thread->last_resume_kind == resume_step)
4193 && linux_fast_tracepoint_collecting (lwp, NULL));
4197 move_out_of_jump_pad_callback (struct inferior_list_entry *entry)
4199 struct thread_info *thread = (struct thread_info *) entry;
4200 struct thread_info *saved_thread;
4201 struct lwp_info *lwp = get_thread_lwp (thread);
4204 if (lwp->suspended != 0)
4206 internal_error (__FILE__, __LINE__,
4207 "LWP %ld is suspended, suspended=%d\n",
4208 lwpid_of (thread), lwp->suspended);
4210 gdb_assert (lwp->stopped);
4212 /* For gdb_breakpoint_here. */
4213 saved_thread = current_thread;
4214 current_thread = thread;
4216 wstat = lwp->status_pending_p ? &lwp->status_pending : NULL;
4218 /* Allow debugging the jump pad, gdb_collect, etc. */
4219 if (!gdb_breakpoint_here (lwp->stop_pc)
4220 && lwp->stop_reason != TARGET_STOPPED_BY_WATCHPOINT
4221 && thread->last_resume_kind != resume_step
4222 && maybe_move_out_of_jump_pad (lwp, wstat))
4225 debug_printf ("LWP %ld needs stabilizing (in jump pad)\n",
4230 lwp->status_pending_p = 0;
4231 enqueue_one_deferred_signal (lwp, wstat);
4234 debug_printf ("Signal %d for LWP %ld deferred "
4236 WSTOPSIG (*wstat), lwpid_of (thread));
4239 linux_resume_one_lwp (lwp, 0, 0, NULL);
4242 lwp_suspended_inc (lwp);
4244 current_thread = saved_thread;
4248 lwp_running (struct inferior_list_entry *entry, void *data)
4250 struct thread_info *thread = (struct thread_info *) entry;
4251 struct lwp_info *lwp = get_thread_lwp (thread);
4253 if (lwp_is_marked_dead (lwp))
4260 /* Stop all lwps that aren't stopped yet, except EXCEPT, if not NULL.
4261 If SUSPEND, then also increase the suspend count of every LWP,
4265 stop_all_lwps (int suspend, struct lwp_info *except)
4267 /* Should not be called recursively. */
4268 gdb_assert (stopping_threads == NOT_STOPPING_THREADS);
4273 debug_printf ("stop_all_lwps (%s, except=%s)\n",
4274 suspend ? "stop-and-suspend" : "stop",
4276 ? target_pid_to_str (ptid_of (get_lwp_thread (except)))
4280 stopping_threads = (suspend
4281 ? STOPPING_AND_SUSPENDING_THREADS
4282 : STOPPING_THREADS);
4285 find_inferior (&all_threads, suspend_and_send_sigstop_callback, except);
4287 find_inferior (&all_threads, send_sigstop_callback, except);
4288 wait_for_sigstop ();
4289 stopping_threads = NOT_STOPPING_THREADS;
4293 debug_printf ("stop_all_lwps done, setting stopping_threads "
4294 "back to !stopping\n");
4299 /* Enqueue one signal in the chain of signals which need to be
4300 delivered to this process on next resume. */
4303 enqueue_pending_signal (struct lwp_info *lwp, int signal, siginfo_t *info)
4305 struct pending_signals *p_sig = XNEW (struct pending_signals);
4307 p_sig->prev = lwp->pending_signals;
4308 p_sig->signal = signal;
4310 memset (&p_sig->info, 0, sizeof (siginfo_t));
4312 memcpy (&p_sig->info, info, sizeof (siginfo_t));
4313 lwp->pending_signals = p_sig;
4316 /* Install breakpoints for software single stepping. */
4319 install_software_single_step_breakpoints (struct lwp_info *lwp)
4323 struct thread_info *thread = get_lwp_thread (lwp);
4324 struct regcache *regcache = get_thread_regcache (thread, 1);
4325 VEC (CORE_ADDR) *next_pcs = NULL;
4326 struct cleanup *old_chain = make_cleanup_restore_current_thread ();
4328 make_cleanup (VEC_cleanup (CORE_ADDR), &next_pcs);
4330 current_thread = thread;
4331 next_pcs = (*the_low_target.get_next_pcs) (regcache);
4333 for (i = 0; VEC_iterate (CORE_ADDR, next_pcs, i, pc); ++i)
4334 set_single_step_breakpoint (pc, current_ptid);
4336 do_cleanups (old_chain);
4339 /* Single step via hardware or software single step.
4340 Return 1 if hardware single stepping, 0 if software single stepping
4341 or can't single step. */
4344 single_step (struct lwp_info* lwp)
4348 if (can_hardware_single_step ())
4352 else if (can_software_single_step ())
4354 install_software_single_step_breakpoints (lwp);
4360 debug_printf ("stepping is not implemented on this target");
4366 /* The signal can be delivered to the inferior if we are not trying to
4367 finish a fast tracepoint collect. Since signal can be delivered in
4368 the step-over, the program may go to signal handler and trap again
4369 after return from the signal handler. We can live with the spurious
4373 lwp_signal_can_be_delivered (struct lwp_info *lwp)
4375 return !lwp->collecting_fast_tracepoint;
4378 /* Resume execution of LWP. If STEP is nonzero, single-step it. If
4379 SIGNAL is nonzero, give it that signal. */
4382 linux_resume_one_lwp_throw (struct lwp_info *lwp,
4383 int step, int signal, siginfo_t *info)
4385 struct thread_info *thread = get_lwp_thread (lwp);
4386 struct thread_info *saved_thread;
4387 int fast_tp_collecting;
4389 struct process_info *proc = get_thread_process (thread);
4391 /* Note that target description may not be initialised
4392 (proc->tdesc == NULL) at this point because the program hasn't
4393 stopped at the first instruction yet. It means GDBserver skips
4394 the extra traps from the wrapper program (see option --wrapper).
4395 Code in this function that requires register access should be
4396 guarded by proc->tdesc == NULL or something else. */
4398 if (lwp->stopped == 0)
4401 gdb_assert (lwp->waitstatus.kind == TARGET_WAITKIND_IGNORE);
4403 fast_tp_collecting = lwp->collecting_fast_tracepoint;
4405 gdb_assert (!stabilizing_threads || fast_tp_collecting);
4407 /* Cancel actions that rely on GDB not changing the PC (e.g., the
4408 user used the "jump" command, or "set $pc = foo"). */
4409 if (thread->while_stepping != NULL && lwp->stop_pc != get_pc (lwp))
4411 /* Collecting 'while-stepping' actions doesn't make sense
4413 release_while_stepping_state_list (thread);
4416 /* If we have pending signals or status, and a new signal, enqueue the
4417 signal. Also enqueue the signal if it can't be delivered to the
4418 inferior right now. */
4420 && (lwp->status_pending_p
4421 || lwp->pending_signals != NULL
4422 || !lwp_signal_can_be_delivered (lwp)))
4424 enqueue_pending_signal (lwp, signal, info);
4426 /* Postpone any pending signal. It was enqueued above. */
4430 if (lwp->status_pending_p)
4433 debug_printf ("Not resuming lwp %ld (%s, stop %s);"
4434 " has pending status\n",
4435 lwpid_of (thread), step ? "step" : "continue",
4436 lwp->stop_expected ? "expected" : "not expected");
4440 saved_thread = current_thread;
4441 current_thread = thread;
4443 /* This bit needs some thinking about. If we get a signal that
4444 we must report while a single-step reinsert is still pending,
4445 we often end up resuming the thread. It might be better to
4446 (ew) allow a stack of pending events; then we could be sure that
4447 the reinsert happened right away and not lose any signals.
4449 Making this stack would also shrink the window in which breakpoints are
4450 uninserted (see comment in linux_wait_for_lwp) but not enough for
4451 complete correctness, so it won't solve that problem. It may be
4452 worthwhile just to solve this one, however. */
4453 if (lwp->bp_reinsert != 0)
4456 debug_printf (" pending reinsert at 0x%s\n",
4457 paddress (lwp->bp_reinsert));
4459 if (can_hardware_single_step ())
4461 if (fast_tp_collecting == 0)
4464 fprintf (stderr, "BAD - reinserting but not stepping.\n");
4466 fprintf (stderr, "BAD - reinserting and suspended(%d).\n",
4471 step = maybe_hw_step (thread);
4474 if (fast_tp_collecting == 1)
4477 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
4478 " (exit-jump-pad-bkpt)\n",
4481 else if (fast_tp_collecting == 2)
4484 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
4485 " single-stepping\n",
4488 if (can_hardware_single_step ())
4492 internal_error (__FILE__, __LINE__,
4493 "moving out of jump pad single-stepping"
4494 " not implemented on this target");
4498 /* If we have while-stepping actions in this thread set it stepping.
4499 If we have a signal to deliver, it may or may not be set to
4500 SIG_IGN, we don't know. Assume so, and allow collecting
4501 while-stepping into a signal handler. A possible smart thing to
4502 do would be to set an internal breakpoint at the signal return
4503 address, continue, and carry on catching this while-stepping
4504 action only when that breakpoint is hit. A future
4506 if (thread->while_stepping != NULL)
4509 debug_printf ("lwp %ld has a while-stepping action -> forcing step.\n",
4512 step = single_step (lwp);
4515 if (proc->tdesc != NULL && the_low_target.get_pc != NULL)
4517 struct regcache *regcache = get_thread_regcache (current_thread, 1);
4519 lwp->stop_pc = (*the_low_target.get_pc) (regcache);
4523 debug_printf (" %s from pc 0x%lx\n", step ? "step" : "continue",
4524 (long) lwp->stop_pc);
4528 /* If we have pending signals, consume one if it can be delivered to
4530 if (lwp->pending_signals != NULL && lwp_signal_can_be_delivered (lwp))
4532 struct pending_signals **p_sig;
4534 p_sig = &lwp->pending_signals;
4535 while ((*p_sig)->prev != NULL)
4536 p_sig = &(*p_sig)->prev;
4538 signal = (*p_sig)->signal;
4539 if ((*p_sig)->info.si_signo != 0)
4540 ptrace (PTRACE_SETSIGINFO, lwpid_of (thread), (PTRACE_TYPE_ARG3) 0,
4548 debug_printf ("Resuming lwp %ld (%s, signal %d, stop %s)\n",
4549 lwpid_of (thread), step ? "step" : "continue", signal,
4550 lwp->stop_expected ? "expected" : "not expected");
4552 if (the_low_target.prepare_to_resume != NULL)
4553 the_low_target.prepare_to_resume (lwp);
4555 regcache_invalidate_thread (thread);
4557 lwp->stepping = step;
4559 ptrace_request = PTRACE_SINGLESTEP;
4560 else if (gdb_catching_syscalls_p (lwp))
4561 ptrace_request = PTRACE_SYSCALL;
4563 ptrace_request = PTRACE_CONT;
4564 ptrace (ptrace_request,
4566 (PTRACE_TYPE_ARG3) 0,
4567 /* Coerce to a uintptr_t first to avoid potential gcc warning
4568 of coercing an 8 byte integer to a 4 byte pointer. */
4569 (PTRACE_TYPE_ARG4) (uintptr_t) signal);
4571 current_thread = saved_thread;
4573 perror_with_name ("resuming thread");
4575 /* Successfully resumed. Clear state that no longer makes sense,
4576 and mark the LWP as running. Must not do this before resuming
4577 otherwise if that fails other code will be confused. E.g., we'd
4578 later try to stop the LWP and hang forever waiting for a stop
4579 status. Note that we must not throw after this is cleared,
4580 otherwise handle_zombie_lwp_error would get confused. */
4582 lwp->stop_reason = TARGET_STOPPED_BY_NO_REASON;
4585 /* Called when we try to resume a stopped LWP and that errors out. If
4586 the LWP is no longer in ptrace-stopped state (meaning it's zombie,
4587 or about to become), discard the error, clear any pending status
4588 the LWP may have, and return true (we'll collect the exit status
4589 soon enough). Otherwise, return false. */
4592 check_ptrace_stopped_lwp_gone (struct lwp_info *lp)
4594 struct thread_info *thread = get_lwp_thread (lp);
4596 /* If we get an error after resuming the LWP successfully, we'd
4597 confuse !T state for the LWP being gone. */
4598 gdb_assert (lp->stopped);
4600 /* We can't just check whether the LWP is in 'Z (Zombie)' state,
4601 because even if ptrace failed with ESRCH, the tracee may be "not
4602 yet fully dead", but already refusing ptrace requests. In that
4603 case the tracee has 'R (Running)' state for a little bit
4604 (observed in Linux 3.18). See also the note on ESRCH in the
4605 ptrace(2) man page. Instead, check whether the LWP has any state
4606 other than ptrace-stopped. */
4608 /* Don't assume anything if /proc/PID/status can't be read. */
4609 if (linux_proc_pid_is_trace_stopped_nowarn (lwpid_of (thread)) == 0)
4611 lp->stop_reason = TARGET_STOPPED_BY_NO_REASON;
4612 lp->status_pending_p = 0;
4618 /* Like linux_resume_one_lwp_throw, but no error is thrown if the LWP
4619 disappears while we try to resume it. */
4622 linux_resume_one_lwp (struct lwp_info *lwp,
4623 int step, int signal, siginfo_t *info)
4627 linux_resume_one_lwp_throw (lwp, step, signal, info);
4629 CATCH (ex, RETURN_MASK_ERROR)
4631 if (!check_ptrace_stopped_lwp_gone (lwp))
4632 throw_exception (ex);
4637 struct thread_resume_array
4639 struct thread_resume *resume;
4643 /* This function is called once per thread via find_inferior.
4644 ARG is a pointer to a thread_resume_array struct.
4645 We look up the thread specified by ENTRY in ARG, and mark the thread
4646 with a pointer to the appropriate resume request.
4648 This algorithm is O(threads * resume elements), but resume elements
4649 is small (and will remain small at least until GDB supports thread
4653 linux_set_resume_request (struct inferior_list_entry *entry, void *arg)
4655 struct thread_info *thread = (struct thread_info *) entry;
4656 struct lwp_info *lwp = get_thread_lwp (thread);
4658 struct thread_resume_array *r;
4660 r = (struct thread_resume_array *) arg;
4662 for (ndx = 0; ndx < r->n; ndx++)
4664 ptid_t ptid = r->resume[ndx].thread;
4665 if (ptid_equal (ptid, minus_one_ptid)
4666 || ptid_equal (ptid, entry->id)
4667 /* Handle both 'pPID' and 'pPID.-1' as meaning 'all threads
4669 || (ptid_get_pid (ptid) == pid_of (thread)
4670 && (ptid_is_pid (ptid)
4671 || ptid_get_lwp (ptid) == -1)))
4673 if (r->resume[ndx].kind == resume_stop
4674 && thread->last_resume_kind == resume_stop)
4677 debug_printf ("already %s LWP %ld at GDB's request\n",
4678 (thread->last_status.kind
4679 == TARGET_WAITKIND_STOPPED)
4687 /* Ignore (wildcard) resume requests for already-resumed
4689 if (r->resume[ndx].kind != resume_stop
4690 && thread->last_resume_kind != resume_stop)
4693 debug_printf ("already %s LWP %ld at GDB's request\n",
4694 (thread->last_resume_kind
4702 /* Don't let wildcard resumes resume fork children that GDB
4703 does not yet know are new fork children. */
4704 if (lwp->fork_relative != NULL)
4706 struct inferior_list_entry *inf, *tmp;
4707 struct lwp_info *rel = lwp->fork_relative;
4709 if (rel->status_pending_p
4710 && (rel->waitstatus.kind == TARGET_WAITKIND_FORKED
4711 || rel->waitstatus.kind == TARGET_WAITKIND_VFORKED))
4714 debug_printf ("not resuming LWP %ld: has queued stop reply\n",
4720 /* If the thread has a pending event that has already been
4721 reported to GDBserver core, but GDB has not pulled the
4722 event out of the vStopped queue yet, likewise, ignore the
4723 (wildcard) resume request. */
4724 if (in_queued_stop_replies (entry->id))
4727 debug_printf ("not resuming LWP %ld: has queued stop reply\n",
4732 lwp->resume = &r->resume[ndx];
4733 thread->last_resume_kind = lwp->resume->kind;
4735 lwp->step_range_start = lwp->resume->step_range_start;
4736 lwp->step_range_end = lwp->resume->step_range_end;
4738 /* If we had a deferred signal to report, dequeue one now.
4739 This can happen if LWP gets more than one signal while
4740 trying to get out of a jump pad. */
4742 && !lwp->status_pending_p
4743 && dequeue_one_deferred_signal (lwp, &lwp->status_pending))
4745 lwp->status_pending_p = 1;
4748 debug_printf ("Dequeueing deferred signal %d for LWP %ld, "
4749 "leaving status pending.\n",
4750 WSTOPSIG (lwp->status_pending),
4758 /* No resume action for this thread. */
4764 /* find_inferior callback for linux_resume.
4765 Set *FLAG_P if this lwp has an interesting status pending. */
4768 resume_status_pending_p (struct inferior_list_entry *entry, void *flag_p)
4770 struct thread_info *thread = (struct thread_info *) entry;
4771 struct lwp_info *lwp = get_thread_lwp (thread);
4773 /* LWPs which will not be resumed are not interesting, because
4774 we might not wait for them next time through linux_wait. */
4775 if (lwp->resume == NULL)
4778 if (thread_still_has_status_pending_p (thread))
4779 * (int *) flag_p = 1;
4784 /* Return 1 if this lwp that GDB wants running is stopped at an
4785 internal breakpoint that we need to step over. It assumes that any
4786 required STOP_PC adjustment has already been propagated to the
4787 inferior's regcache. */
4790 need_step_over_p (struct inferior_list_entry *entry, void *dummy)
4792 struct thread_info *thread = (struct thread_info *) entry;
4793 struct lwp_info *lwp = get_thread_lwp (thread);
4794 struct thread_info *saved_thread;
4796 struct process_info *proc = get_thread_process (thread);
4798 /* GDBserver is skipping the extra traps from the wrapper program,
4799 don't have to do step over. */
4800 if (proc->tdesc == NULL)
4803 /* LWPs which will not be resumed are not interesting, because we
4804 might not wait for them next time through linux_wait. */
4809 debug_printf ("Need step over [LWP %ld]? Ignoring, not stopped\n",
4814 if (thread->last_resume_kind == resume_stop)
4817 debug_printf ("Need step over [LWP %ld]? Ignoring, should remain"
4823 gdb_assert (lwp->suspended >= 0);
4828 debug_printf ("Need step over [LWP %ld]? Ignoring, suspended\n",
4833 if (lwp->status_pending_p)
4836 debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
4842 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
4846 /* If the PC has changed since we stopped, then don't do anything,
4847 and let the breakpoint/tracepoint be hit. This happens if, for
4848 instance, GDB handled the decr_pc_after_break subtraction itself,
4849 GDB is OOL stepping this thread, or the user has issued a "jump"
4850 command, or poked thread's registers herself. */
4851 if (pc != lwp->stop_pc)
4854 debug_printf ("Need step over [LWP %ld]? Cancelling, PC was changed. "
4855 "Old stop_pc was 0x%s, PC is now 0x%s\n",
4857 paddress (lwp->stop_pc), paddress (pc));
4861 /* On software single step target, resume the inferior with signal
4862 rather than stepping over. */
4863 if (can_software_single_step ()
4864 && lwp->pending_signals != NULL
4865 && lwp_signal_can_be_delivered (lwp))
4868 debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
4875 saved_thread = current_thread;
4876 current_thread = thread;
4878 /* We can only step over breakpoints we know about. */
4879 if (breakpoint_here (pc) || fast_tracepoint_jump_here (pc))
4881 /* Don't step over a breakpoint that GDB expects to hit
4882 though. If the condition is being evaluated on the target's side
4883 and it evaluate to false, step over this breakpoint as well. */
4884 if (gdb_breakpoint_here (pc)
4885 && gdb_condition_true_at_breakpoint (pc)
4886 && gdb_no_commands_at_breakpoint (pc))
4889 debug_printf ("Need step over [LWP %ld]? yes, but found"
4890 " GDB breakpoint at 0x%s; skipping step over\n",
4891 lwpid_of (thread), paddress (pc));
4893 current_thread = saved_thread;
4899 debug_printf ("Need step over [LWP %ld]? yes, "
4900 "found breakpoint at 0x%s\n",
4901 lwpid_of (thread), paddress (pc));
4903 /* We've found an lwp that needs stepping over --- return 1 so
4904 that find_inferior stops looking. */
4905 current_thread = saved_thread;
4911 current_thread = saved_thread;
4914 debug_printf ("Need step over [LWP %ld]? No, no breakpoint found"
4916 lwpid_of (thread), paddress (pc));
4921 /* Start a step-over operation on LWP. When LWP stopped at a
4922 breakpoint, to make progress, we need to remove the breakpoint out
4923 of the way. If we let other threads run while we do that, they may
4924 pass by the breakpoint location and miss hitting it. To avoid
4925 that, a step-over momentarily stops all threads while LWP is
4926 single-stepped by either hardware or software while the breakpoint
4927 is temporarily uninserted from the inferior. When the single-step
4928 finishes, we reinsert the breakpoint, and let all threads that are
4929 supposed to be running, run again. */
4932 start_step_over (struct lwp_info *lwp)
4934 struct thread_info *thread = get_lwp_thread (lwp);
4935 struct thread_info *saved_thread;
4940 debug_printf ("Starting step-over on LWP %ld. Stopping all threads\n",
4943 stop_all_lwps (1, lwp);
4945 if (lwp->suspended != 0)
4947 internal_error (__FILE__, __LINE__,
4948 "LWP %ld suspended=%d\n", lwpid_of (thread),
4953 debug_printf ("Done stopping all threads for step-over.\n");
4955 /* Note, we should always reach here with an already adjusted PC,
4956 either by GDB (if we're resuming due to GDB's request), or by our
4957 caller, if we just finished handling an internal breakpoint GDB
4958 shouldn't care about. */
4961 saved_thread = current_thread;
4962 current_thread = thread;
4964 lwp->bp_reinsert = pc;
4965 uninsert_breakpoints_at (pc);
4966 uninsert_fast_tracepoint_jumps_at (pc);
4968 step = single_step (lwp);
4970 current_thread = saved_thread;
4972 linux_resume_one_lwp (lwp, step, 0, NULL);
4974 /* Require next event from this LWP. */
4975 step_over_bkpt = thread->entry.id;
4979 /* Finish a step-over. Reinsert the breakpoint we had uninserted in
4980 start_step_over, if still there, and delete any single-step
4981 breakpoints we've set, on non hardware single-step targets. */
4984 finish_step_over (struct lwp_info *lwp)
4986 if (lwp->bp_reinsert != 0)
4988 struct thread_info *saved_thread = current_thread;
4991 debug_printf ("Finished step over.\n");
4993 current_thread = get_lwp_thread (lwp);
4995 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
4996 may be no breakpoint to reinsert there by now. */
4997 reinsert_breakpoints_at (lwp->bp_reinsert);
4998 reinsert_fast_tracepoint_jumps_at (lwp->bp_reinsert);
5000 lwp->bp_reinsert = 0;
5002 /* Delete any single-step breakpoints. No longer needed. We
5003 don't have to worry about other threads hitting this trap,
5004 and later not being able to explain it, because we were
5005 stepping over a breakpoint, and we hold all threads but
5006 LWP stopped while doing that. */
5007 if (!can_hardware_single_step ())
5009 gdb_assert (has_single_step_breakpoints (current_thread));
5010 delete_single_step_breakpoints (current_thread);
5013 step_over_bkpt = null_ptid;
5014 current_thread = saved_thread;
5021 /* If there's a step over in progress, wait until all threads stop
5022 (that is, until the stepping thread finishes its step), and
5023 unsuspend all lwps. The stepping thread ends with its status
5024 pending, which is processed later when we get back to processing
5028 complete_ongoing_step_over (void)
5030 if (!ptid_equal (step_over_bkpt, null_ptid))
5032 struct lwp_info *lwp;
5037 debug_printf ("detach: step over in progress, finish it first\n");
5039 /* Passing NULL_PTID as filter indicates we want all events to
5040 be left pending. Eventually this returns when there are no
5041 unwaited-for children left. */
5042 ret = linux_wait_for_event_filtered (minus_one_ptid, null_ptid,
5044 gdb_assert (ret == -1);
5046 lwp = find_lwp_pid (step_over_bkpt);
5048 finish_step_over (lwp);
5049 step_over_bkpt = null_ptid;
5050 unsuspend_all_lwps (lwp);
5054 /* This function is called once per thread. We check the thread's resume
5055 request, which will tell us whether to resume, step, or leave the thread
5056 stopped; and what signal, if any, it should be sent.
5058 For threads which we aren't explicitly told otherwise, we preserve
5059 the stepping flag; this is used for stepping over gdbserver-placed
5062 If pending_flags was set in any thread, we queue any needed
5063 signals, since we won't actually resume. We already have a pending
5064 event to report, so we don't need to preserve any step requests;
5065 they should be re-issued if necessary. */
5068 linux_resume_one_thread (struct inferior_list_entry *entry, void *arg)
5070 struct thread_info *thread = (struct thread_info *) entry;
5071 struct lwp_info *lwp = get_thread_lwp (thread);
5072 int leave_all_stopped = * (int *) arg;
5075 if (lwp->resume == NULL)
5078 if (lwp->resume->kind == resume_stop)
5081 debug_printf ("resume_stop request for LWP %ld\n", lwpid_of (thread));
5086 debug_printf ("stopping LWP %ld\n", lwpid_of (thread));
5088 /* Stop the thread, and wait for the event asynchronously,
5089 through the event loop. */
5095 debug_printf ("already stopped LWP %ld\n",
5098 /* The LWP may have been stopped in an internal event that
5099 was not meant to be notified back to GDB (e.g., gdbserver
5100 breakpoint), so we should be reporting a stop event in
5103 /* If the thread already has a pending SIGSTOP, this is a
5104 no-op. Otherwise, something later will presumably resume
5105 the thread and this will cause it to cancel any pending
5106 operation, due to last_resume_kind == resume_stop. If
5107 the thread already has a pending status to report, we
5108 will still report it the next time we wait - see
5109 status_pending_p_callback. */
5111 /* If we already have a pending signal to report, then
5112 there's no need to queue a SIGSTOP, as this means we're
5113 midway through moving the LWP out of the jumppad, and we
5114 will report the pending signal as soon as that is
5116 if (lwp->pending_signals_to_report == NULL)
5120 /* For stop requests, we're done. */
5122 thread->last_status.kind = TARGET_WAITKIND_IGNORE;
5126 /* If this thread which is about to be resumed has a pending status,
5127 then don't resume it - we can just report the pending status.
5128 Likewise if it is suspended, because e.g., another thread is
5129 stepping past a breakpoint. Make sure to queue any signals that
5130 would otherwise be sent. In all-stop mode, we do this decision
5131 based on if *any* thread has a pending status. If there's a
5132 thread that needs the step-over-breakpoint dance, then don't
5133 resume any other thread but that particular one. */
5134 leave_pending = (lwp->suspended
5135 || lwp->status_pending_p
5136 || leave_all_stopped);
5138 /* If we have a new signal, enqueue the signal. */
5139 if (lwp->resume->sig != 0)
5141 siginfo_t info, *info_p;
5143 /* If this is the same signal we were previously stopped by,
5144 make sure to queue its siginfo. */
5145 if (WIFSTOPPED (lwp->last_status)
5146 && WSTOPSIG (lwp->last_status) == lwp->resume->sig
5147 && ptrace (PTRACE_GETSIGINFO, lwpid_of (thread),
5148 (PTRACE_TYPE_ARG3) 0, &info) == 0)
5153 enqueue_pending_signal (lwp, lwp->resume->sig, info_p);
5159 debug_printf ("resuming LWP %ld\n", lwpid_of (thread));
5161 proceed_one_lwp (entry, NULL);
5166 debug_printf ("leaving LWP %ld stopped\n", lwpid_of (thread));
5169 thread->last_status.kind = TARGET_WAITKIND_IGNORE;
5175 linux_resume (struct thread_resume *resume_info, size_t n)
5177 struct thread_resume_array array = { resume_info, n };
5178 struct thread_info *need_step_over = NULL;
5180 int leave_all_stopped;
5185 debug_printf ("linux_resume:\n");
5188 find_inferior (&all_threads, linux_set_resume_request, &array);
5190 /* If there is a thread which would otherwise be resumed, which has
5191 a pending status, then don't resume any threads - we can just
5192 report the pending status. Make sure to queue any signals that
5193 would otherwise be sent. In non-stop mode, we'll apply this
5194 logic to each thread individually. We consume all pending events
5195 before considering to start a step-over (in all-stop). */
5198 find_inferior (&all_threads, resume_status_pending_p, &any_pending);
5200 /* If there is a thread which would otherwise be resumed, which is
5201 stopped at a breakpoint that needs stepping over, then don't
5202 resume any threads - have it step over the breakpoint with all
5203 other threads stopped, then resume all threads again. Make sure
5204 to queue any signals that would otherwise be delivered or
5206 if (!any_pending && supports_breakpoints ())
5208 = (struct thread_info *) find_inferior (&all_threads,
5209 need_step_over_p, NULL);
5211 leave_all_stopped = (need_step_over != NULL || any_pending);
5215 if (need_step_over != NULL)
5216 debug_printf ("Not resuming all, need step over\n");
5217 else if (any_pending)
5218 debug_printf ("Not resuming, all-stop and found "
5219 "an LWP with pending status\n");
5221 debug_printf ("Resuming, no pending status or step over needed\n");
5224 /* Even if we're leaving threads stopped, queue all signals we'd
5225 otherwise deliver. */
5226 find_inferior (&all_threads, linux_resume_one_thread, &leave_all_stopped);
5229 start_step_over (get_thread_lwp (need_step_over));
5233 debug_printf ("linux_resume done\n");
5237 /* We may have events that were pending that can/should be sent to
5238 the client now. Trigger a linux_wait call. */
5239 if (target_is_async_p ())
5243 /* This function is called once per thread. We check the thread's
5244 last resume request, which will tell us whether to resume, step, or
5245 leave the thread stopped. Any signal the client requested to be
5246 delivered has already been enqueued at this point.
5248 If any thread that GDB wants running is stopped at an internal
5249 breakpoint that needs stepping over, we start a step-over operation
5250 on that particular thread, and leave all others stopped. */
5253 proceed_one_lwp (struct inferior_list_entry *entry, void *except)
5255 struct thread_info *thread = (struct thread_info *) entry;
5256 struct lwp_info *lwp = get_thread_lwp (thread);
5263 debug_printf ("proceed_one_lwp: lwp %ld\n", lwpid_of (thread));
5268 debug_printf (" LWP %ld already running\n", lwpid_of (thread));
5272 if (thread->last_resume_kind == resume_stop
5273 && thread->last_status.kind != TARGET_WAITKIND_IGNORE)
5276 debug_printf (" client wants LWP to remain %ld stopped\n",
5281 if (lwp->status_pending_p)
5284 debug_printf (" LWP %ld has pending status, leaving stopped\n",
5289 gdb_assert (lwp->suspended >= 0);
5294 debug_printf (" LWP %ld is suspended\n", lwpid_of (thread));
5298 if (thread->last_resume_kind == resume_stop
5299 && lwp->pending_signals_to_report == NULL
5300 && lwp->collecting_fast_tracepoint == 0)
5302 /* We haven't reported this LWP as stopped yet (otherwise, the
5303 last_status.kind check above would catch it, and we wouldn't
5304 reach here. This LWP may have been momentarily paused by a
5305 stop_all_lwps call while handling for example, another LWP's
5306 step-over. In that case, the pending expected SIGSTOP signal
5307 that was queued at vCont;t handling time will have already
5308 been consumed by wait_for_sigstop, and so we need to requeue
5309 another one here. Note that if the LWP already has a SIGSTOP
5310 pending, this is a no-op. */
5313 debug_printf ("Client wants LWP %ld to stop. "
5314 "Making sure it has a SIGSTOP pending\n",
5320 if (thread->last_resume_kind == resume_step)
5323 debug_printf (" stepping LWP %ld, client wants it stepping\n",
5326 /* If resume_step is requested by GDB, install single-step
5327 breakpoints when the thread is about to be actually resumed if
5328 the single-step breakpoints weren't removed. */
5329 if (can_software_single_step ()
5330 && !has_single_step_breakpoints (thread))
5331 install_software_single_step_breakpoints (lwp);
5333 step = maybe_hw_step (thread);
5335 else if (lwp->bp_reinsert != 0)
5338 debug_printf (" stepping LWP %ld, reinsert set\n",
5341 step = maybe_hw_step (thread);
5346 linux_resume_one_lwp (lwp, step, 0, NULL);
5351 unsuspend_and_proceed_one_lwp (struct inferior_list_entry *entry, void *except)
5353 struct thread_info *thread = (struct thread_info *) entry;
5354 struct lwp_info *lwp = get_thread_lwp (thread);
5359 lwp_suspended_decr (lwp);
5361 return proceed_one_lwp (entry, except);
5364 /* When we finish a step-over, set threads running again. If there's
5365 another thread that may need a step-over, now's the time to start
5366 it. Eventually, we'll move all threads past their breakpoints. */
5369 proceed_all_lwps (void)
5371 struct thread_info *need_step_over;
5373 /* If there is a thread which would otherwise be resumed, which is
5374 stopped at a breakpoint that needs stepping over, then don't
5375 resume any threads - have it step over the breakpoint with all
5376 other threads stopped, then resume all threads again. */
5378 if (supports_breakpoints ())
5381 = (struct thread_info *) find_inferior (&all_threads,
5382 need_step_over_p, NULL);
5384 if (need_step_over != NULL)
5387 debug_printf ("proceed_all_lwps: found "
5388 "thread %ld needing a step-over\n",
5389 lwpid_of (need_step_over));
5391 start_step_over (get_thread_lwp (need_step_over));
5397 debug_printf ("Proceeding, no step-over needed\n");
5399 find_inferior (&all_threads, proceed_one_lwp, NULL);
5402 /* Stopped LWPs that the client wanted to be running, that don't have
5403 pending statuses, are set to run again, except for EXCEPT, if not
5404 NULL. This undoes a stop_all_lwps call. */
5407 unstop_all_lwps (int unsuspend, struct lwp_info *except)
5413 debug_printf ("unstopping all lwps, except=(LWP %ld)\n",
5414 lwpid_of (get_lwp_thread (except)));
5416 debug_printf ("unstopping all lwps\n");
5420 find_inferior (&all_threads, unsuspend_and_proceed_one_lwp, except);
5422 find_inferior (&all_threads, proceed_one_lwp, except);
5426 debug_printf ("unstop_all_lwps done\n");
5432 #ifdef HAVE_LINUX_REGSETS
5434 #define use_linux_regsets 1
5436 /* Returns true if REGSET has been disabled. */
5439 regset_disabled (struct regsets_info *info, struct regset_info *regset)
5441 return (info->disabled_regsets != NULL
5442 && info->disabled_regsets[regset - info->regsets]);
5445 /* Disable REGSET. */
5448 disable_regset (struct regsets_info *info, struct regset_info *regset)
5452 dr_offset = regset - info->regsets;
5453 if (info->disabled_regsets == NULL)
5454 info->disabled_regsets = (char *) xcalloc (1, info->num_regsets);
5455 info->disabled_regsets[dr_offset] = 1;
5459 regsets_fetch_inferior_registers (struct regsets_info *regsets_info,
5460 struct regcache *regcache)
5462 struct regset_info *regset;
5463 int saw_general_regs = 0;
5467 pid = lwpid_of (current_thread);
5468 for (regset = regsets_info->regsets; regset->size >= 0; regset++)
5473 if (regset->size == 0 || regset_disabled (regsets_info, regset))
5476 buf = xmalloc (regset->size);
5478 nt_type = regset->nt_type;
5482 iov.iov_len = regset->size;
5483 data = (void *) &iov;
5489 res = ptrace (regset->get_request, pid,
5490 (PTRACE_TYPE_ARG3) (long) nt_type, data);
5492 res = ptrace (regset->get_request, pid, data, nt_type);
5498 /* If we get EIO on a regset, do not try it again for
5499 this process mode. */
5500 disable_regset (regsets_info, regset);
5502 else if (errno == ENODATA)
5504 /* ENODATA may be returned if the regset is currently
5505 not "active". This can happen in normal operation,
5506 so suppress the warning in this case. */
5508 else if (errno == ESRCH)
5510 /* At this point, ESRCH should mean the process is
5511 already gone, in which case we simply ignore attempts
5512 to read its registers. */
5517 sprintf (s, "ptrace(regsets_fetch_inferior_registers) PID=%d",
5524 if (regset->type == GENERAL_REGS)
5525 saw_general_regs = 1;
5526 regset->store_function (regcache, buf);
5530 if (saw_general_regs)
5537 regsets_store_inferior_registers (struct regsets_info *regsets_info,
5538 struct regcache *regcache)
5540 struct regset_info *regset;
5541 int saw_general_regs = 0;
5545 pid = lwpid_of (current_thread);
5546 for (regset = regsets_info->regsets; regset->size >= 0; regset++)
5551 if (regset->size == 0 || regset_disabled (regsets_info, regset)
5552 || regset->fill_function == NULL)
5555 buf = xmalloc (regset->size);
5557 /* First fill the buffer with the current register set contents,
5558 in case there are any items in the kernel's regset that are
5559 not in gdbserver's regcache. */
5561 nt_type = regset->nt_type;
5565 iov.iov_len = regset->size;
5566 data = (void *) &iov;
5572 res = ptrace (regset->get_request, pid,
5573 (PTRACE_TYPE_ARG3) (long) nt_type, data);
5575 res = ptrace (regset->get_request, pid, data, nt_type);
5580 /* Then overlay our cached registers on that. */
5581 regset->fill_function (regcache, buf);
5583 /* Only now do we write the register set. */
5585 res = ptrace (regset->set_request, pid,
5586 (PTRACE_TYPE_ARG3) (long) nt_type, data);
5588 res = ptrace (regset->set_request, pid, data, nt_type);
5596 /* If we get EIO on a regset, do not try it again for
5597 this process mode. */
5598 disable_regset (regsets_info, regset);
5600 else if (errno == ESRCH)
5602 /* At this point, ESRCH should mean the process is
5603 already gone, in which case we simply ignore attempts
5604 to change its registers. See also the related
5605 comment in linux_resume_one_lwp. */
5611 perror ("Warning: ptrace(regsets_store_inferior_registers)");
5614 else if (regset->type == GENERAL_REGS)
5615 saw_general_regs = 1;
5618 if (saw_general_regs)
5624 #else /* !HAVE_LINUX_REGSETS */
5626 #define use_linux_regsets 0
5627 #define regsets_fetch_inferior_registers(regsets_info, regcache) 1
5628 #define regsets_store_inferior_registers(regsets_info, regcache) 1
5632 /* Return 1 if register REGNO is supported by one of the regset ptrace
5633 calls or 0 if it has to be transferred individually. */
5636 linux_register_in_regsets (const struct regs_info *regs_info, int regno)
5638 unsigned char mask = 1 << (regno % 8);
5639 size_t index = regno / 8;
5641 return (use_linux_regsets
5642 && (regs_info->regset_bitmap == NULL
5643 || (regs_info->regset_bitmap[index] & mask) != 0));
5646 #ifdef HAVE_LINUX_USRREGS
5649 register_addr (const struct usrregs_info *usrregs, int regnum)
5653 if (regnum < 0 || regnum >= usrregs->num_regs)
5654 error ("Invalid register number %d.", regnum);
5656 addr = usrregs->regmap[regnum];
5661 /* Fetch one register. */
5663 fetch_register (const struct usrregs_info *usrregs,
5664 struct regcache *regcache, int regno)
5671 if (regno >= usrregs->num_regs)
5673 if ((*the_low_target.cannot_fetch_register) (regno))
5676 regaddr = register_addr (usrregs, regno);
5680 size = ((register_size (regcache->tdesc, regno)
5681 + sizeof (PTRACE_XFER_TYPE) - 1)
5682 & -sizeof (PTRACE_XFER_TYPE));
5683 buf = (char *) alloca (size);
5685 pid = lwpid_of (current_thread);
5686 for (i = 0; i < size; i += sizeof (PTRACE_XFER_TYPE))
5689 *(PTRACE_XFER_TYPE *) (buf + i) =
5690 ptrace (PTRACE_PEEKUSER, pid,
5691 /* Coerce to a uintptr_t first to avoid potential gcc warning
5692 of coercing an 8 byte integer to a 4 byte pointer. */
5693 (PTRACE_TYPE_ARG3) (uintptr_t) regaddr, (PTRACE_TYPE_ARG4) 0);
5694 regaddr += sizeof (PTRACE_XFER_TYPE);
5696 error ("reading register %d: %s", regno, strerror (errno));
5699 if (the_low_target.supply_ptrace_register)
5700 the_low_target.supply_ptrace_register (regcache, regno, buf);
5702 supply_register (regcache, regno, buf);
5705 /* Store one register. */
5707 store_register (const struct usrregs_info *usrregs,
5708 struct regcache *regcache, int regno)
5715 if (regno >= usrregs->num_regs)
5717 if ((*the_low_target.cannot_store_register) (regno))
5720 regaddr = register_addr (usrregs, regno);
5724 size = ((register_size (regcache->tdesc, regno)
5725 + sizeof (PTRACE_XFER_TYPE) - 1)
5726 & -sizeof (PTRACE_XFER_TYPE));
5727 buf = (char *) alloca (size);
5728 memset (buf, 0, size);
5730 if (the_low_target.collect_ptrace_register)
5731 the_low_target.collect_ptrace_register (regcache, regno, buf);
5733 collect_register (regcache, regno, buf);
5735 pid = lwpid_of (current_thread);
5736 for (i = 0; i < size; i += sizeof (PTRACE_XFER_TYPE))
5739 ptrace (PTRACE_POKEUSER, pid,
5740 /* Coerce to a uintptr_t first to avoid potential gcc warning
5741 about coercing an 8 byte integer to a 4 byte pointer. */
5742 (PTRACE_TYPE_ARG3) (uintptr_t) regaddr,
5743 (PTRACE_TYPE_ARG4) *(PTRACE_XFER_TYPE *) (buf + i));
5746 /* At this point, ESRCH should mean the process is
5747 already gone, in which case we simply ignore attempts
5748 to change its registers. See also the related
5749 comment in linux_resume_one_lwp. */
5753 if ((*the_low_target.cannot_store_register) (regno) == 0)
5754 error ("writing register %d: %s", regno, strerror (errno));
5756 regaddr += sizeof (PTRACE_XFER_TYPE);
5760 /* Fetch all registers, or just one, from the child process.
5761 If REGNO is -1, do this for all registers, skipping any that are
5762 assumed to have been retrieved by regsets_fetch_inferior_registers,
5763 unless ALL is non-zero.
5764 Otherwise, REGNO specifies which register (so we can save time). */
5766 usr_fetch_inferior_registers (const struct regs_info *regs_info,
5767 struct regcache *regcache, int regno, int all)
5769 struct usrregs_info *usr = regs_info->usrregs;
5773 for (regno = 0; regno < usr->num_regs; regno++)
5774 if (all || !linux_register_in_regsets (regs_info, regno))
5775 fetch_register (usr, regcache, regno);
5778 fetch_register (usr, regcache, regno);
5781 /* Store our register values back into the inferior.
5782 If REGNO is -1, do this for all registers, skipping any that are
5783 assumed to have been saved by regsets_store_inferior_registers,
5784 unless ALL is non-zero.
5785 Otherwise, REGNO specifies which register (so we can save time). */
5787 usr_store_inferior_registers (const struct regs_info *regs_info,
5788 struct regcache *regcache, int regno, int all)
5790 struct usrregs_info *usr = regs_info->usrregs;
5794 for (regno = 0; regno < usr->num_regs; regno++)
5795 if (all || !linux_register_in_regsets (regs_info, regno))
5796 store_register (usr, regcache, regno);
5799 store_register (usr, regcache, regno);
5802 #else /* !HAVE_LINUX_USRREGS */
5804 #define usr_fetch_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
5805 #define usr_store_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
5811 linux_fetch_registers (struct regcache *regcache, int regno)
5815 const struct regs_info *regs_info = (*the_low_target.regs_info) ();
5819 if (the_low_target.fetch_register != NULL
5820 && regs_info->usrregs != NULL)
5821 for (regno = 0; regno < regs_info->usrregs->num_regs; regno++)
5822 (*the_low_target.fetch_register) (regcache, regno);
5824 all = regsets_fetch_inferior_registers (regs_info->regsets_info, regcache);
5825 if (regs_info->usrregs != NULL)
5826 usr_fetch_inferior_registers (regs_info, regcache, -1, all);
5830 if (the_low_target.fetch_register != NULL
5831 && (*the_low_target.fetch_register) (regcache, regno))
5834 use_regsets = linux_register_in_regsets (regs_info, regno);
5836 all = regsets_fetch_inferior_registers (regs_info->regsets_info,
5838 if ((!use_regsets || all) && regs_info->usrregs != NULL)
5839 usr_fetch_inferior_registers (regs_info, regcache, regno, 1);
5844 linux_store_registers (struct regcache *regcache, int regno)
5848 const struct regs_info *regs_info = (*the_low_target.regs_info) ();
5852 all = regsets_store_inferior_registers (regs_info->regsets_info,
5854 if (regs_info->usrregs != NULL)
5855 usr_store_inferior_registers (regs_info, regcache, regno, all);
5859 use_regsets = linux_register_in_regsets (regs_info, regno);
5861 all = regsets_store_inferior_registers (regs_info->regsets_info,
5863 if ((!use_regsets || all) && regs_info->usrregs != NULL)
5864 usr_store_inferior_registers (regs_info, regcache, regno, 1);
5869 /* Copy LEN bytes from inferior's memory starting at MEMADDR
5870 to debugger memory starting at MYADDR. */
5873 linux_read_memory (CORE_ADDR memaddr, unsigned char *myaddr, int len)
5875 int pid = lwpid_of (current_thread);
5876 register PTRACE_XFER_TYPE *buffer;
5877 register CORE_ADDR addr;
5884 /* Try using /proc. Don't bother for one word. */
5885 if (len >= 3 * sizeof (long))
5889 /* We could keep this file open and cache it - possibly one per
5890 thread. That requires some juggling, but is even faster. */
5891 sprintf (filename, "/proc/%d/mem", pid);
5892 fd = open (filename, O_RDONLY | O_LARGEFILE);
5896 /* If pread64 is available, use it. It's faster if the kernel
5897 supports it (only one syscall), and it's 64-bit safe even on
5898 32-bit platforms (for instance, SPARC debugging a SPARC64
5901 bytes = pread64 (fd, myaddr, len, memaddr);
5904 if (lseek (fd, memaddr, SEEK_SET) != -1)
5905 bytes = read (fd, myaddr, len);
5912 /* Some data was read, we'll try to get the rest with ptrace. */
5922 /* Round starting address down to longword boundary. */
5923 addr = memaddr & -(CORE_ADDR) sizeof (PTRACE_XFER_TYPE);
5924 /* Round ending address up; get number of longwords that makes. */
5925 count = ((((memaddr + len) - addr) + sizeof (PTRACE_XFER_TYPE) - 1)
5926 / sizeof (PTRACE_XFER_TYPE));
5927 /* Allocate buffer of that many longwords. */
5928 buffer = XALLOCAVEC (PTRACE_XFER_TYPE, count);
5930 /* Read all the longwords */
5932 for (i = 0; i < count; i++, addr += sizeof (PTRACE_XFER_TYPE))
5934 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5935 about coercing an 8 byte integer to a 4 byte pointer. */
5936 buffer[i] = ptrace (PTRACE_PEEKTEXT, pid,
5937 (PTRACE_TYPE_ARG3) (uintptr_t) addr,
5938 (PTRACE_TYPE_ARG4) 0);
5944 /* Copy appropriate bytes out of the buffer. */
5947 i *= sizeof (PTRACE_XFER_TYPE);
5948 i -= memaddr & (sizeof (PTRACE_XFER_TYPE) - 1);
5950 (char *) buffer + (memaddr & (sizeof (PTRACE_XFER_TYPE) - 1)),
5957 /* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
5958 memory at MEMADDR. On failure (cannot write to the inferior)
5959 returns the value of errno. Always succeeds if LEN is zero. */
5962 linux_write_memory (CORE_ADDR memaddr, const unsigned char *myaddr, int len)
5965 /* Round starting address down to longword boundary. */
5966 register CORE_ADDR addr = memaddr & -(CORE_ADDR) sizeof (PTRACE_XFER_TYPE);
5967 /* Round ending address up; get number of longwords that makes. */
5969 = (((memaddr + len) - addr) + sizeof (PTRACE_XFER_TYPE) - 1)
5970 / sizeof (PTRACE_XFER_TYPE);
5972 /* Allocate buffer of that many longwords. */
5973 register PTRACE_XFER_TYPE *buffer = XALLOCAVEC (PTRACE_XFER_TYPE, count);
5975 int pid = lwpid_of (current_thread);
5979 /* Zero length write always succeeds. */
5985 /* Dump up to four bytes. */
5986 char str[4 * 2 + 1];
5988 int dump = len < 4 ? len : 4;
5990 for (i = 0; i < dump; i++)
5992 sprintf (p, "%02x", myaddr[i]);
5997 debug_printf ("Writing %s to 0x%08lx in process %d\n",
5998 str, (long) memaddr, pid);
6001 /* Fill start and end extra bytes of buffer with existing memory data. */
6004 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
6005 about coercing an 8 byte integer to a 4 byte pointer. */
6006 buffer[0] = ptrace (PTRACE_PEEKTEXT, pid,
6007 (PTRACE_TYPE_ARG3) (uintptr_t) addr,
6008 (PTRACE_TYPE_ARG4) 0);
6016 = ptrace (PTRACE_PEEKTEXT, pid,
6017 /* Coerce to a uintptr_t first to avoid potential gcc warning
6018 about coercing an 8 byte integer to a 4 byte pointer. */
6019 (PTRACE_TYPE_ARG3) (uintptr_t) (addr + (count - 1)
6020 * sizeof (PTRACE_XFER_TYPE)),
6021 (PTRACE_TYPE_ARG4) 0);
6026 /* Copy data to be written over corresponding part of buffer. */
6028 memcpy ((char *) buffer + (memaddr & (sizeof (PTRACE_XFER_TYPE) - 1)),
6031 /* Write the entire buffer. */
6033 for (i = 0; i < count; i++, addr += sizeof (PTRACE_XFER_TYPE))
6036 ptrace (PTRACE_POKETEXT, pid,
6037 /* Coerce to a uintptr_t first to avoid potential gcc warning
6038 about coercing an 8 byte integer to a 4 byte pointer. */
6039 (PTRACE_TYPE_ARG3) (uintptr_t) addr,
6040 (PTRACE_TYPE_ARG4) buffer[i]);
6049 linux_look_up_symbols (void)
6051 #ifdef USE_THREAD_DB
6052 struct process_info *proc = current_process ();
6054 if (proc->priv->thread_db != NULL)
6062 linux_request_interrupt (void)
6064 extern unsigned long signal_pid;
6066 /* Send a SIGINT to the process group. This acts just like the user
6067 typed a ^C on the controlling terminal. */
6068 kill (-signal_pid, SIGINT);
6071 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
6072 to debugger memory starting at MYADDR. */
6075 linux_read_auxv (CORE_ADDR offset, unsigned char *myaddr, unsigned int len)
6077 char filename[PATH_MAX];
6079 int pid = lwpid_of (current_thread);
6081 xsnprintf (filename, sizeof filename, "/proc/%d/auxv", pid);
6083 fd = open (filename, O_RDONLY);
6087 if (offset != (CORE_ADDR) 0
6088 && lseek (fd, (off_t) offset, SEEK_SET) != (off_t) offset)
6091 n = read (fd, myaddr, len);
6098 /* These breakpoint and watchpoint related wrapper functions simply
6099 pass on the function call if the target has registered a
6100 corresponding function. */
6103 linux_supports_z_point_type (char z_type)
6105 return (the_low_target.supports_z_point_type != NULL
6106 && the_low_target.supports_z_point_type (z_type));
6110 linux_insert_point (enum raw_bkpt_type type, CORE_ADDR addr,
6111 int size, struct raw_breakpoint *bp)
6113 if (type == raw_bkpt_type_sw)
6114 return insert_memory_breakpoint (bp);
6115 else if (the_low_target.insert_point != NULL)
6116 return the_low_target.insert_point (type, addr, size, bp);
6118 /* Unsupported (see target.h). */
6123 linux_remove_point (enum raw_bkpt_type type, CORE_ADDR addr,
6124 int size, struct raw_breakpoint *bp)
6126 if (type == raw_bkpt_type_sw)
6127 return remove_memory_breakpoint (bp);
6128 else if (the_low_target.remove_point != NULL)
6129 return the_low_target.remove_point (type, addr, size, bp);
6131 /* Unsupported (see target.h). */
6135 /* Implement the to_stopped_by_sw_breakpoint target_ops
6139 linux_stopped_by_sw_breakpoint (void)
6141 struct lwp_info *lwp = get_thread_lwp (current_thread);
6143 return (lwp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT);
6146 /* Implement the to_supports_stopped_by_sw_breakpoint target_ops
6150 linux_supports_stopped_by_sw_breakpoint (void)
6152 return USE_SIGTRAP_SIGINFO;
6155 /* Implement the to_stopped_by_hw_breakpoint target_ops
6159 linux_stopped_by_hw_breakpoint (void)
6161 struct lwp_info *lwp = get_thread_lwp (current_thread);
6163 return (lwp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT);
6166 /* Implement the to_supports_stopped_by_hw_breakpoint target_ops
6170 linux_supports_stopped_by_hw_breakpoint (void)
6172 return USE_SIGTRAP_SIGINFO;
6175 /* Implement the supports_hardware_single_step target_ops method. */
6178 linux_supports_hardware_single_step (void)
6180 return can_hardware_single_step ();
6184 linux_supports_software_single_step (void)
6186 return can_software_single_step ();
6190 linux_stopped_by_watchpoint (void)
6192 struct lwp_info *lwp = get_thread_lwp (current_thread);
6194 return lwp->stop_reason == TARGET_STOPPED_BY_WATCHPOINT;
6198 linux_stopped_data_address (void)
6200 struct lwp_info *lwp = get_thread_lwp (current_thread);
6202 return lwp->stopped_data_address;
6205 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
6206 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
6207 && defined(PT_TEXT_END_ADDR)
6209 /* This is only used for targets that define PT_TEXT_ADDR,
6210 PT_DATA_ADDR and PT_TEXT_END_ADDR. If those are not defined, supposedly
6211 the target has different ways of acquiring this information, like
6214 /* Under uClinux, programs are loaded at non-zero offsets, which we need
6215 to tell gdb about. */
6218 linux_read_offsets (CORE_ADDR *text_p, CORE_ADDR *data_p)
6220 unsigned long text, text_end, data;
6221 int pid = lwpid_of (current_thread);
6225 text = ptrace (PTRACE_PEEKUSER, pid, (PTRACE_TYPE_ARG3) PT_TEXT_ADDR,
6226 (PTRACE_TYPE_ARG4) 0);
6227 text_end = ptrace (PTRACE_PEEKUSER, pid, (PTRACE_TYPE_ARG3) PT_TEXT_END_ADDR,
6228 (PTRACE_TYPE_ARG4) 0);
6229 data = ptrace (PTRACE_PEEKUSER, pid, (PTRACE_TYPE_ARG3) PT_DATA_ADDR,
6230 (PTRACE_TYPE_ARG4) 0);
6234 /* Both text and data offsets produced at compile-time (and so
6235 used by gdb) are relative to the beginning of the program,
6236 with the data segment immediately following the text segment.
6237 However, the actual runtime layout in memory may put the data
6238 somewhere else, so when we send gdb a data base-address, we
6239 use the real data base address and subtract the compile-time
6240 data base-address from it (which is just the length of the
6241 text segment). BSS immediately follows data in both
6244 *data_p = data - (text_end - text);
6253 linux_qxfer_osdata (const char *annex,
6254 unsigned char *readbuf, unsigned const char *writebuf,
6255 CORE_ADDR offset, int len)
6257 return linux_common_xfer_osdata (annex, readbuf, offset, len);
6260 /* Convert a native/host siginfo object, into/from the siginfo in the
6261 layout of the inferiors' architecture. */
6264 siginfo_fixup (siginfo_t *siginfo, gdb_byte *inf_siginfo, int direction)
6268 if (the_low_target.siginfo_fixup != NULL)
6269 done = the_low_target.siginfo_fixup (siginfo, inf_siginfo, direction);
6271 /* If there was no callback, or the callback didn't do anything,
6272 then just do a straight memcpy. */
6276 memcpy (siginfo, inf_siginfo, sizeof (siginfo_t));
6278 memcpy (inf_siginfo, siginfo, sizeof (siginfo_t));
6283 linux_xfer_siginfo (const char *annex, unsigned char *readbuf,
6284 unsigned const char *writebuf, CORE_ADDR offset, int len)
6288 gdb_byte inf_siginfo[sizeof (siginfo_t)];
6290 if (current_thread == NULL)
6293 pid = lwpid_of (current_thread);
6296 debug_printf ("%s siginfo for lwp %d.\n",
6297 readbuf != NULL ? "Reading" : "Writing",
6300 if (offset >= sizeof (siginfo))
6303 if (ptrace (PTRACE_GETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo) != 0)
6306 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
6307 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
6308 inferior with a 64-bit GDBSERVER should look the same as debugging it
6309 with a 32-bit GDBSERVER, we need to convert it. */
6310 siginfo_fixup (&siginfo, inf_siginfo, 0);
6312 if (offset + len > sizeof (siginfo))
6313 len = sizeof (siginfo) - offset;
6315 if (readbuf != NULL)
6316 memcpy (readbuf, inf_siginfo + offset, len);
6319 memcpy (inf_siginfo + offset, writebuf, len);
6321 /* Convert back to ptrace layout before flushing it out. */
6322 siginfo_fixup (&siginfo, inf_siginfo, 1);
6324 if (ptrace (PTRACE_SETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo) != 0)
6331 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
6332 so we notice when children change state; as the handler for the
6333 sigsuspend in my_waitpid. */
6336 sigchld_handler (int signo)
6338 int old_errno = errno;
6344 /* fprintf is not async-signal-safe, so call write
6346 if (write (2, "sigchld_handler\n",
6347 sizeof ("sigchld_handler\n") - 1) < 0)
6348 break; /* just ignore */
6352 if (target_is_async_p ())
6353 async_file_mark (); /* trigger a linux_wait */
6359 linux_supports_non_stop (void)
6365 linux_async (int enable)
6367 int previous = target_is_async_p ();
6370 debug_printf ("linux_async (%d), previous=%d\n",
6373 if (previous != enable)
6376 sigemptyset (&mask);
6377 sigaddset (&mask, SIGCHLD);
6379 sigprocmask (SIG_BLOCK, &mask, NULL);
6383 if (pipe (linux_event_pipe) == -1)
6385 linux_event_pipe[0] = -1;
6386 linux_event_pipe[1] = -1;
6387 sigprocmask (SIG_UNBLOCK, &mask, NULL);
6389 warning ("creating event pipe failed.");
6393 fcntl (linux_event_pipe[0], F_SETFL, O_NONBLOCK);
6394 fcntl (linux_event_pipe[1], F_SETFL, O_NONBLOCK);
6396 /* Register the event loop handler. */
6397 add_file_handler (linux_event_pipe[0],
6398 handle_target_event, NULL);
6400 /* Always trigger a linux_wait. */
6405 delete_file_handler (linux_event_pipe[0]);
6407 close (linux_event_pipe[0]);
6408 close (linux_event_pipe[1]);
6409 linux_event_pipe[0] = -1;
6410 linux_event_pipe[1] = -1;
6413 sigprocmask (SIG_UNBLOCK, &mask, NULL);
6420 linux_start_non_stop (int nonstop)
6422 /* Register or unregister from event-loop accordingly. */
6423 linux_async (nonstop);
6425 if (target_is_async_p () != (nonstop != 0))
6432 linux_supports_multi_process (void)
6437 /* Check if fork events are supported. */
6440 linux_supports_fork_events (void)
6442 return linux_supports_tracefork ();
6445 /* Check if vfork events are supported. */
6448 linux_supports_vfork_events (void)
6450 return linux_supports_tracefork ();
6453 /* Check if exec events are supported. */
6456 linux_supports_exec_events (void)
6458 return linux_supports_traceexec ();
6461 /* Callback for 'find_inferior'. Set the (possibly changed) ptrace
6462 options for the specified lwp. */
6465 reset_lwp_ptrace_options_callback (struct inferior_list_entry *entry,
6468 struct thread_info *thread = (struct thread_info *) entry;
6469 struct lwp_info *lwp = get_thread_lwp (thread);
6473 /* Stop the lwp so we can modify its ptrace options. */
6474 lwp->must_set_ptrace_flags = 1;
6475 linux_stop_lwp (lwp);
6479 /* Already stopped; go ahead and set the ptrace options. */
6480 struct process_info *proc = find_process_pid (pid_of (thread));
6481 int options = linux_low_ptrace_options (proc->attached);
6483 linux_enable_event_reporting (lwpid_of (thread), options);
6484 lwp->must_set_ptrace_flags = 0;
6490 /* Target hook for 'handle_new_gdb_connection'. Causes a reset of the
6491 ptrace flags for all inferiors. This is in case the new GDB connection
6492 doesn't support the same set of events that the previous one did. */
6495 linux_handle_new_gdb_connection (void)
6499 /* Request that all the lwps reset their ptrace options. */
6500 find_inferior (&all_threads, reset_lwp_ptrace_options_callback , &pid);
6504 linux_supports_disable_randomization (void)
6506 #ifdef HAVE_PERSONALITY
6514 linux_supports_agent (void)
6520 linux_supports_range_stepping (void)
6522 if (*the_low_target.supports_range_stepping == NULL)
6525 return (*the_low_target.supports_range_stepping) ();
6528 /* Enumerate spufs IDs for process PID. */
6530 spu_enumerate_spu_ids (long pid, unsigned char *buf, CORE_ADDR offset, int len)
6536 struct dirent *entry;
6538 sprintf (path, "/proc/%ld/fd", pid);
6539 dir = opendir (path);
6544 while ((entry = readdir (dir)) != NULL)
6550 fd = atoi (entry->d_name);
6554 sprintf (path, "/proc/%ld/fd/%d", pid, fd);
6555 if (stat (path, &st) != 0)
6557 if (!S_ISDIR (st.st_mode))
6560 if (statfs (path, &stfs) != 0)
6562 if (stfs.f_type != SPUFS_MAGIC)
6565 if (pos >= offset && pos + 4 <= offset + len)
6567 *(unsigned int *)(buf + pos - offset) = fd;
6577 /* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
6578 object type, using the /proc file system. */
6580 linux_qxfer_spu (const char *annex, unsigned char *readbuf,
6581 unsigned const char *writebuf,
6582 CORE_ADDR offset, int len)
6584 long pid = lwpid_of (current_thread);
6589 if (!writebuf && !readbuf)
6597 return spu_enumerate_spu_ids (pid, readbuf, offset, len);
6600 sprintf (buf, "/proc/%ld/fd/%s", pid, annex);
6601 fd = open (buf, writebuf? O_WRONLY : O_RDONLY);
6606 && lseek (fd, (off_t) offset, SEEK_SET) != (off_t) offset)
6613 ret = write (fd, writebuf, (size_t) len);
6615 ret = read (fd, readbuf, (size_t) len);
6621 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
6622 struct target_loadseg
6624 /* Core address to which the segment is mapped. */
6626 /* VMA recorded in the program header. */
6628 /* Size of this segment in memory. */
6632 # if defined PT_GETDSBT
6633 struct target_loadmap
6635 /* Protocol version number, must be zero. */
6637 /* Pointer to the DSBT table, its size, and the DSBT index. */
6638 unsigned *dsbt_table;
6639 unsigned dsbt_size, dsbt_index;
6640 /* Number of segments in this map. */
6642 /* The actual memory map. */
6643 struct target_loadseg segs[/*nsegs*/];
6645 # define LINUX_LOADMAP PT_GETDSBT
6646 # define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
6647 # define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
6649 struct target_loadmap
6651 /* Protocol version number, must be zero. */
6653 /* Number of segments in this map. */
6655 /* The actual memory map. */
6656 struct target_loadseg segs[/*nsegs*/];
6658 # define LINUX_LOADMAP PTRACE_GETFDPIC
6659 # define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
6660 # define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
6664 linux_read_loadmap (const char *annex, CORE_ADDR offset,
6665 unsigned char *myaddr, unsigned int len)
6667 int pid = lwpid_of (current_thread);
6669 struct target_loadmap *data = NULL;
6670 unsigned int actual_length, copy_length;
6672 if (strcmp (annex, "exec") == 0)
6673 addr = (int) LINUX_LOADMAP_EXEC;
6674 else if (strcmp (annex, "interp") == 0)
6675 addr = (int) LINUX_LOADMAP_INTERP;
6679 if (ptrace (LINUX_LOADMAP, pid, addr, &data) != 0)
6685 actual_length = sizeof (struct target_loadmap)
6686 + sizeof (struct target_loadseg) * data->nsegs;
6688 if (offset < 0 || offset > actual_length)
6691 copy_length = actual_length - offset < len ? actual_length - offset : len;
6692 memcpy (myaddr, (char *) data + offset, copy_length);
6696 # define linux_read_loadmap NULL
6697 #endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
6700 linux_process_qsupported (char **features, int count)
6702 if (the_low_target.process_qsupported != NULL)
6703 the_low_target.process_qsupported (features, count);
6707 linux_supports_catch_syscall (void)
6709 return (the_low_target.get_syscall_trapinfo != NULL
6710 && linux_supports_tracesysgood ());
6714 linux_get_ipa_tdesc_idx (void)
6716 if (the_low_target.get_ipa_tdesc_idx == NULL)
6719 return (*the_low_target.get_ipa_tdesc_idx) ();
6723 linux_supports_tracepoints (void)
6725 if (*the_low_target.supports_tracepoints == NULL)
6728 return (*the_low_target.supports_tracepoints) ();
6732 linux_read_pc (struct regcache *regcache)
6734 if (the_low_target.get_pc == NULL)
6737 return (*the_low_target.get_pc) (regcache);
6741 linux_write_pc (struct regcache *regcache, CORE_ADDR pc)
6743 gdb_assert (the_low_target.set_pc != NULL);
6745 (*the_low_target.set_pc) (regcache, pc);
6749 linux_thread_stopped (struct thread_info *thread)
6751 return get_thread_lwp (thread)->stopped;
6754 /* This exposes stop-all-threads functionality to other modules. */
6757 linux_pause_all (int freeze)
6759 stop_all_lwps (freeze, NULL);
6762 /* This exposes unstop-all-threads functionality to other gdbserver
6766 linux_unpause_all (int unfreeze)
6768 unstop_all_lwps (unfreeze, NULL);
6772 linux_prepare_to_access_memory (void)
6774 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6777 linux_pause_all (1);
6782 linux_done_accessing_memory (void)
6784 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6787 linux_unpause_all (1);
6791 linux_install_fast_tracepoint_jump_pad (CORE_ADDR tpoint, CORE_ADDR tpaddr,
6792 CORE_ADDR collector,
6795 CORE_ADDR *jump_entry,
6796 CORE_ADDR *trampoline,
6797 ULONGEST *trampoline_size,
6798 unsigned char *jjump_pad_insn,
6799 ULONGEST *jjump_pad_insn_size,
6800 CORE_ADDR *adjusted_insn_addr,
6801 CORE_ADDR *adjusted_insn_addr_end,
6804 return (*the_low_target.install_fast_tracepoint_jump_pad)
6805 (tpoint, tpaddr, collector, lockaddr, orig_size,
6806 jump_entry, trampoline, trampoline_size,
6807 jjump_pad_insn, jjump_pad_insn_size,
6808 adjusted_insn_addr, adjusted_insn_addr_end,
6812 static struct emit_ops *
6813 linux_emit_ops (void)
6815 if (the_low_target.emit_ops != NULL)
6816 return (*the_low_target.emit_ops) ();
6822 linux_get_min_fast_tracepoint_insn_len (void)
6824 return (*the_low_target.get_min_fast_tracepoint_insn_len) ();
6827 /* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
6830 get_phdr_phnum_from_proc_auxv (const int pid, const int is_elf64,
6831 CORE_ADDR *phdr_memaddr, int *num_phdr)
6833 char filename[PATH_MAX];
6835 const int auxv_size = is_elf64
6836 ? sizeof (Elf64_auxv_t) : sizeof (Elf32_auxv_t);
6837 char buf[sizeof (Elf64_auxv_t)]; /* The larger of the two. */
6839 xsnprintf (filename, sizeof filename, "/proc/%d/auxv", pid);
6841 fd = open (filename, O_RDONLY);
6847 while (read (fd, buf, auxv_size) == auxv_size
6848 && (*phdr_memaddr == 0 || *num_phdr == 0))
6852 Elf64_auxv_t *const aux = (Elf64_auxv_t *) buf;
6854 switch (aux->a_type)
6857 *phdr_memaddr = aux->a_un.a_val;
6860 *num_phdr = aux->a_un.a_val;
6866 Elf32_auxv_t *const aux = (Elf32_auxv_t *) buf;
6868 switch (aux->a_type)
6871 *phdr_memaddr = aux->a_un.a_val;
6874 *num_phdr = aux->a_un.a_val;
6882 if (*phdr_memaddr == 0 || *num_phdr == 0)
6884 warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
6885 "phdr_memaddr = %ld, phdr_num = %d",
6886 (long) *phdr_memaddr, *num_phdr);
6893 /* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
6896 get_dynamic (const int pid, const int is_elf64)
6898 CORE_ADDR phdr_memaddr, relocation;
6900 unsigned char *phdr_buf;
6901 const int phdr_size = is_elf64 ? sizeof (Elf64_Phdr) : sizeof (Elf32_Phdr);
6903 if (get_phdr_phnum_from_proc_auxv (pid, is_elf64, &phdr_memaddr, &num_phdr))
6906 gdb_assert (num_phdr < 100); /* Basic sanity check. */
6907 phdr_buf = (unsigned char *) alloca (num_phdr * phdr_size);
6909 if (linux_read_memory (phdr_memaddr, phdr_buf, num_phdr * phdr_size))
6912 /* Compute relocation: it is expected to be 0 for "regular" executables,
6913 non-zero for PIE ones. */
6915 for (i = 0; relocation == -1 && i < num_phdr; i++)
6918 Elf64_Phdr *const p = (Elf64_Phdr *) (phdr_buf + i * phdr_size);
6920 if (p->p_type == PT_PHDR)
6921 relocation = phdr_memaddr - p->p_vaddr;
6925 Elf32_Phdr *const p = (Elf32_Phdr *) (phdr_buf + i * phdr_size);
6927 if (p->p_type == PT_PHDR)
6928 relocation = phdr_memaddr - p->p_vaddr;
6931 if (relocation == -1)
6933 /* PT_PHDR is optional, but necessary for PIE in general. Fortunately
6934 any real world executables, including PIE executables, have always
6935 PT_PHDR present. PT_PHDR is not present in some shared libraries or
6936 in fpc (Free Pascal 2.4) binaries but neither of those have a need for
6937 or present DT_DEBUG anyway (fpc binaries are statically linked).
6939 Therefore if there exists DT_DEBUG there is always also PT_PHDR.
6941 GDB could find RELOCATION also from AT_ENTRY - e_entry. */
6946 for (i = 0; i < num_phdr; i++)
6950 Elf64_Phdr *const p = (Elf64_Phdr *) (phdr_buf + i * phdr_size);
6952 if (p->p_type == PT_DYNAMIC)
6953 return p->p_vaddr + relocation;
6957 Elf32_Phdr *const p = (Elf32_Phdr *) (phdr_buf + i * phdr_size);
6959 if (p->p_type == PT_DYNAMIC)
6960 return p->p_vaddr + relocation;
6967 /* Return &_r_debug in the inferior, or -1 if not present. Return value
6968 can be 0 if the inferior does not yet have the library list initialized.
6969 We look for DT_MIPS_RLD_MAP first. MIPS executables use this instead of
6970 DT_DEBUG, although they sometimes contain an unused DT_DEBUG entry too. */
6973 get_r_debug (const int pid, const int is_elf64)
6975 CORE_ADDR dynamic_memaddr;
6976 const int dyn_size = is_elf64 ? sizeof (Elf64_Dyn) : sizeof (Elf32_Dyn);
6977 unsigned char buf[sizeof (Elf64_Dyn)]; /* The larger of the two. */
6980 dynamic_memaddr = get_dynamic (pid, is_elf64);
6981 if (dynamic_memaddr == 0)
6984 while (linux_read_memory (dynamic_memaddr, buf, dyn_size) == 0)
6988 Elf64_Dyn *const dyn = (Elf64_Dyn *) buf;
6989 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
6993 unsigned char buf[sizeof (Elf64_Xword)];
6997 #ifdef DT_MIPS_RLD_MAP
6998 if (dyn->d_tag == DT_MIPS_RLD_MAP)
7000 if (linux_read_memory (dyn->d_un.d_val,
7001 rld_map.buf, sizeof (rld_map.buf)) == 0)
7006 #endif /* DT_MIPS_RLD_MAP */
7007 #ifdef DT_MIPS_RLD_MAP_REL
7008 if (dyn->d_tag == DT_MIPS_RLD_MAP_REL)
7010 if (linux_read_memory (dyn->d_un.d_val + dynamic_memaddr,
7011 rld_map.buf, sizeof (rld_map.buf)) == 0)
7016 #endif /* DT_MIPS_RLD_MAP_REL */
7018 if (dyn->d_tag == DT_DEBUG && map == -1)
7019 map = dyn->d_un.d_val;
7021 if (dyn->d_tag == DT_NULL)
7026 Elf32_Dyn *const dyn = (Elf32_Dyn *) buf;
7027 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
7031 unsigned char buf[sizeof (Elf32_Word)];
7035 #ifdef DT_MIPS_RLD_MAP
7036 if (dyn->d_tag == DT_MIPS_RLD_MAP)
7038 if (linux_read_memory (dyn->d_un.d_val,
7039 rld_map.buf, sizeof (rld_map.buf)) == 0)
7044 #endif /* DT_MIPS_RLD_MAP */
7045 #ifdef DT_MIPS_RLD_MAP_REL
7046 if (dyn->d_tag == DT_MIPS_RLD_MAP_REL)
7048 if (linux_read_memory (dyn->d_un.d_val + dynamic_memaddr,
7049 rld_map.buf, sizeof (rld_map.buf)) == 0)
7054 #endif /* DT_MIPS_RLD_MAP_REL */
7056 if (dyn->d_tag == DT_DEBUG && map == -1)
7057 map = dyn->d_un.d_val;
7059 if (dyn->d_tag == DT_NULL)
7063 dynamic_memaddr += dyn_size;
7069 /* Read one pointer from MEMADDR in the inferior. */
7072 read_one_ptr (CORE_ADDR memaddr, CORE_ADDR *ptr, int ptr_size)
7076 /* Go through a union so this works on either big or little endian
7077 hosts, when the inferior's pointer size is smaller than the size
7078 of CORE_ADDR. It is assumed the inferior's endianness is the
7079 same of the superior's. */
7082 CORE_ADDR core_addr;
7087 ret = linux_read_memory (memaddr, &addr.uc, ptr_size);
7090 if (ptr_size == sizeof (CORE_ADDR))
7091 *ptr = addr.core_addr;
7092 else if (ptr_size == sizeof (unsigned int))
7095 gdb_assert_not_reached ("unhandled pointer size");
7100 struct link_map_offsets
7102 /* Offset and size of r_debug.r_version. */
7103 int r_version_offset;
7105 /* Offset and size of r_debug.r_map. */
7108 /* Offset to l_addr field in struct link_map. */
7111 /* Offset to l_name field in struct link_map. */
7114 /* Offset to l_ld field in struct link_map. */
7117 /* Offset to l_next field in struct link_map. */
7120 /* Offset to l_prev field in struct link_map. */
7124 /* Construct qXfer:libraries-svr4:read reply. */
7127 linux_qxfer_libraries_svr4 (const char *annex, unsigned char *readbuf,
7128 unsigned const char *writebuf,
7129 CORE_ADDR offset, int len)
7132 unsigned document_len;
7133 struct process_info_private *const priv = current_process ()->priv;
7134 char filename[PATH_MAX];
7137 static const struct link_map_offsets lmo_32bit_offsets =
7139 0, /* r_version offset. */
7140 4, /* r_debug.r_map offset. */
7141 0, /* l_addr offset in link_map. */
7142 4, /* l_name offset in link_map. */
7143 8, /* l_ld offset in link_map. */
7144 12, /* l_next offset in link_map. */
7145 16 /* l_prev offset in link_map. */
7148 static const struct link_map_offsets lmo_64bit_offsets =
7150 0, /* r_version offset. */
7151 8, /* r_debug.r_map offset. */
7152 0, /* l_addr offset in link_map. */
7153 8, /* l_name offset in link_map. */
7154 16, /* l_ld offset in link_map. */
7155 24, /* l_next offset in link_map. */
7156 32 /* l_prev offset in link_map. */
7158 const struct link_map_offsets *lmo;
7159 unsigned int machine;
7161 CORE_ADDR lm_addr = 0, lm_prev = 0;
7162 int allocated = 1024;
7164 CORE_ADDR l_name, l_addr, l_ld, l_next, l_prev;
7165 int header_done = 0;
7167 if (writebuf != NULL)
7169 if (readbuf == NULL)
7172 pid = lwpid_of (current_thread);
7173 xsnprintf (filename, sizeof filename, "/proc/%d/exe", pid);
7174 is_elf64 = elf_64_file_p (filename, &machine);
7175 lmo = is_elf64 ? &lmo_64bit_offsets : &lmo_32bit_offsets;
7176 ptr_size = is_elf64 ? 8 : 4;
7178 while (annex[0] != '\0')
7184 sep = strchr (annex, '=');
7189 if (len == 5 && startswith (annex, "start"))
7191 else if (len == 4 && startswith (annex, "prev"))
7195 annex = strchr (sep, ';');
7202 annex = decode_address_to_semicolon (addrp, sep + 1);
7209 if (priv->r_debug == 0)
7210 priv->r_debug = get_r_debug (pid, is_elf64);
7212 /* We failed to find DT_DEBUG. Such situation will not change
7213 for this inferior - do not retry it. Report it to GDB as
7214 E01, see for the reasons at the GDB solib-svr4.c side. */
7215 if (priv->r_debug == (CORE_ADDR) -1)
7218 if (priv->r_debug != 0)
7220 if (linux_read_memory (priv->r_debug + lmo->r_version_offset,
7221 (unsigned char *) &r_version,
7222 sizeof (r_version)) != 0
7225 warning ("unexpected r_debug version %d", r_version);
7227 else if (read_one_ptr (priv->r_debug + lmo->r_map_offset,
7228 &lm_addr, ptr_size) != 0)
7230 warning ("unable to read r_map from 0x%lx",
7231 (long) priv->r_debug + lmo->r_map_offset);
7236 document = (char *) xmalloc (allocated);
7237 strcpy (document, "<library-list-svr4 version=\"1.0\"");
7238 p = document + strlen (document);
7241 && read_one_ptr (lm_addr + lmo->l_name_offset,
7242 &l_name, ptr_size) == 0
7243 && read_one_ptr (lm_addr + lmo->l_addr_offset,
7244 &l_addr, ptr_size) == 0
7245 && read_one_ptr (lm_addr + lmo->l_ld_offset,
7246 &l_ld, ptr_size) == 0
7247 && read_one_ptr (lm_addr + lmo->l_prev_offset,
7248 &l_prev, ptr_size) == 0
7249 && read_one_ptr (lm_addr + lmo->l_next_offset,
7250 &l_next, ptr_size) == 0)
7252 unsigned char libname[PATH_MAX];
7254 if (lm_prev != l_prev)
7256 warning ("Corrupted shared library list: 0x%lx != 0x%lx",
7257 (long) lm_prev, (long) l_prev);
7261 /* Ignore the first entry even if it has valid name as the first entry
7262 corresponds to the main executable. The first entry should not be
7263 skipped if the dynamic loader was loaded late by a static executable
7264 (see solib-svr4.c parameter ignore_first). But in such case the main
7265 executable does not have PT_DYNAMIC present and this function already
7266 exited above due to failed get_r_debug. */
7269 sprintf (p, " main-lm=\"0x%lx\"", (unsigned long) lm_addr);
7274 /* Not checking for error because reading may stop before
7275 we've got PATH_MAX worth of characters. */
7277 linux_read_memory (l_name, libname, sizeof (libname) - 1);
7278 libname[sizeof (libname) - 1] = '\0';
7279 if (libname[0] != '\0')
7281 /* 6x the size for xml_escape_text below. */
7282 size_t len = 6 * strlen ((char *) libname);
7287 /* Terminate `<library-list-svr4'. */
7292 while (allocated < p - document + len + 200)
7294 /* Expand to guarantee sufficient storage. */
7295 uintptr_t document_len = p - document;
7297 document = (char *) xrealloc (document, 2 * allocated);
7299 p = document + document_len;
7302 name = xml_escape_text ((char *) libname);
7303 p += sprintf (p, "<library name=\"%s\" lm=\"0x%lx\" "
7304 "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
7305 name, (unsigned long) lm_addr,
7306 (unsigned long) l_addr, (unsigned long) l_ld);
7317 /* Empty list; terminate `<library-list-svr4'. */
7321 strcpy (p, "</library-list-svr4>");
7323 document_len = strlen (document);
7324 if (offset < document_len)
7325 document_len -= offset;
7328 if (len > document_len)
7331 memcpy (readbuf, document + offset, len);
7337 #ifdef HAVE_LINUX_BTRACE
7339 /* See to_disable_btrace target method. */
7342 linux_low_disable_btrace (struct btrace_target_info *tinfo)
7344 enum btrace_error err;
7346 err = linux_disable_btrace (tinfo);
7347 return (err == BTRACE_ERR_NONE ? 0 : -1);
7350 /* Encode an Intel Processor Trace configuration. */
7353 linux_low_encode_pt_config (struct buffer *buffer,
7354 const struct btrace_data_pt_config *config)
7356 buffer_grow_str (buffer, "<pt-config>\n");
7358 switch (config->cpu.vendor)
7361 buffer_xml_printf (buffer, "<cpu vendor=\"GenuineIntel\" family=\"%u\" "
7362 "model=\"%u\" stepping=\"%u\"/>\n",
7363 config->cpu.family, config->cpu.model,
7364 config->cpu.stepping);
7371 buffer_grow_str (buffer, "</pt-config>\n");
7374 /* Encode a raw buffer. */
7377 linux_low_encode_raw (struct buffer *buffer, const gdb_byte *data,
7383 /* We use hex encoding - see common/rsp-low.h. */
7384 buffer_grow_str (buffer, "<raw>\n");
7390 elem[0] = tohex ((*data >> 4) & 0xf);
7391 elem[1] = tohex (*data++ & 0xf);
7393 buffer_grow (buffer, elem, 2);
7396 buffer_grow_str (buffer, "</raw>\n");
7399 /* See to_read_btrace target method. */
7402 linux_low_read_btrace (struct btrace_target_info *tinfo, struct buffer *buffer,
7403 enum btrace_read_type type)
7405 struct btrace_data btrace;
7406 struct btrace_block *block;
7407 enum btrace_error err;
7410 btrace_data_init (&btrace);
7412 err = linux_read_btrace (&btrace, tinfo, type);
7413 if (err != BTRACE_ERR_NONE)
7415 if (err == BTRACE_ERR_OVERFLOW)
7416 buffer_grow_str0 (buffer, "E.Overflow.");
7418 buffer_grow_str0 (buffer, "E.Generic Error.");
7423 switch (btrace.format)
7425 case BTRACE_FORMAT_NONE:
7426 buffer_grow_str0 (buffer, "E.No Trace.");
7429 case BTRACE_FORMAT_BTS:
7430 buffer_grow_str (buffer, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
7431 buffer_grow_str (buffer, "<btrace version=\"1.0\">\n");
7434 VEC_iterate (btrace_block_s, btrace.variant.bts.blocks, i, block);
7436 buffer_xml_printf (buffer, "<block begin=\"0x%s\" end=\"0x%s\"/>\n",
7437 paddress (block->begin), paddress (block->end));
7439 buffer_grow_str0 (buffer, "</btrace>\n");
7442 case BTRACE_FORMAT_PT:
7443 buffer_grow_str (buffer, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
7444 buffer_grow_str (buffer, "<btrace version=\"1.0\">\n");
7445 buffer_grow_str (buffer, "<pt>\n");
7447 linux_low_encode_pt_config (buffer, &btrace.variant.pt.config);
7449 linux_low_encode_raw (buffer, btrace.variant.pt.data,
7450 btrace.variant.pt.size);
7452 buffer_grow_str (buffer, "</pt>\n");
7453 buffer_grow_str0 (buffer, "</btrace>\n");
7457 buffer_grow_str0 (buffer, "E.Unsupported Trace Format.");
7461 btrace_data_fini (&btrace);
7465 btrace_data_fini (&btrace);
7469 /* See to_btrace_conf target method. */
7472 linux_low_btrace_conf (const struct btrace_target_info *tinfo,
7473 struct buffer *buffer)
7475 const struct btrace_config *conf;
7477 buffer_grow_str (buffer, "<!DOCTYPE btrace-conf SYSTEM \"btrace-conf.dtd\">\n");
7478 buffer_grow_str (buffer, "<btrace-conf version=\"1.0\">\n");
7480 conf = linux_btrace_conf (tinfo);
7483 switch (conf->format)
7485 case BTRACE_FORMAT_NONE:
7488 case BTRACE_FORMAT_BTS:
7489 buffer_xml_printf (buffer, "<bts");
7490 buffer_xml_printf (buffer, " size=\"0x%x\"", conf->bts.size);
7491 buffer_xml_printf (buffer, " />\n");
7494 case BTRACE_FORMAT_PT:
7495 buffer_xml_printf (buffer, "<pt");
7496 buffer_xml_printf (buffer, " size=\"0x%x\"", conf->pt.size);
7497 buffer_xml_printf (buffer, "/>\n");
7502 buffer_grow_str0 (buffer, "</btrace-conf>\n");
7505 #endif /* HAVE_LINUX_BTRACE */
7507 /* See nat/linux-nat.h. */
7510 current_lwp_ptid (void)
7512 return ptid_of (current_thread);
7515 /* Implementation of the target_ops method "breakpoint_kind_from_pc". */
7518 linux_breakpoint_kind_from_pc (CORE_ADDR *pcptr)
7520 if (the_low_target.breakpoint_kind_from_pc != NULL)
7521 return (*the_low_target.breakpoint_kind_from_pc) (pcptr);
7523 return default_breakpoint_kind_from_pc (pcptr);
7526 /* Implementation of the target_ops method "sw_breakpoint_from_kind". */
7528 static const gdb_byte *
7529 linux_sw_breakpoint_from_kind (int kind, int *size)
7531 gdb_assert (the_low_target.sw_breakpoint_from_kind != NULL);
7533 return (*the_low_target.sw_breakpoint_from_kind) (kind, size);
7536 /* Implementation of the target_ops method
7537 "breakpoint_kind_from_current_state". */
7540 linux_breakpoint_kind_from_current_state (CORE_ADDR *pcptr)
7542 if (the_low_target.breakpoint_kind_from_current_state != NULL)
7543 return (*the_low_target.breakpoint_kind_from_current_state) (pcptr);
7545 return linux_breakpoint_kind_from_pc (pcptr);
7548 /* Default implementation of linux_target_ops method "set_pc" for
7549 32-bit pc register which is literally named "pc". */
7552 linux_set_pc_32bit (struct regcache *regcache, CORE_ADDR pc)
7554 uint32_t newpc = pc;
7556 supply_register_by_name (regcache, "pc", &newpc);
7559 /* Default implementation of linux_target_ops method "get_pc" for
7560 32-bit pc register which is literally named "pc". */
7563 linux_get_pc_32bit (struct regcache *regcache)
7567 collect_register_by_name (regcache, "pc", &pc);
7569 debug_printf ("stop pc is 0x%" PRIx32 "\n", pc);
7573 /* Default implementation of linux_target_ops method "set_pc" for
7574 64-bit pc register which is literally named "pc". */
7577 linux_set_pc_64bit (struct regcache *regcache, CORE_ADDR pc)
7579 uint64_t newpc = pc;
7581 supply_register_by_name (regcache, "pc", &newpc);
7584 /* Default implementation of linux_target_ops method "get_pc" for
7585 64-bit pc register which is literally named "pc". */
7588 linux_get_pc_64bit (struct regcache *regcache)
7592 collect_register_by_name (regcache, "pc", &pc);
7594 debug_printf ("stop pc is 0x%" PRIx64 "\n", pc);
7599 static struct target_ops linux_target_ops = {
7600 linux_create_inferior,
7601 linux_post_create_inferior,
7610 linux_fetch_registers,
7611 linux_store_registers,
7612 linux_prepare_to_access_memory,
7613 linux_done_accessing_memory,
7616 linux_look_up_symbols,
7617 linux_request_interrupt,
7619 linux_supports_z_point_type,
7622 linux_stopped_by_sw_breakpoint,
7623 linux_supports_stopped_by_sw_breakpoint,
7624 linux_stopped_by_hw_breakpoint,
7625 linux_supports_stopped_by_hw_breakpoint,
7626 linux_supports_hardware_single_step,
7627 linux_stopped_by_watchpoint,
7628 linux_stopped_data_address,
7629 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
7630 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
7631 && defined(PT_TEXT_END_ADDR)
7636 #ifdef USE_THREAD_DB
7637 thread_db_get_tls_address,
7642 hostio_last_error_from_errno,
7645 linux_supports_non_stop,
7647 linux_start_non_stop,
7648 linux_supports_multi_process,
7649 linux_supports_fork_events,
7650 linux_supports_vfork_events,
7651 linux_supports_exec_events,
7652 linux_handle_new_gdb_connection,
7653 #ifdef USE_THREAD_DB
7654 thread_db_handle_monitor_command,
7658 linux_common_core_of_thread,
7660 linux_process_qsupported,
7661 linux_supports_tracepoints,
7664 linux_thread_stopped,
7668 linux_stabilize_threads,
7669 linux_install_fast_tracepoint_jump_pad,
7671 linux_supports_disable_randomization,
7672 linux_get_min_fast_tracepoint_insn_len,
7673 linux_qxfer_libraries_svr4,
7674 linux_supports_agent,
7675 #ifdef HAVE_LINUX_BTRACE
7676 linux_supports_btrace,
7677 linux_enable_btrace,
7678 linux_low_disable_btrace,
7679 linux_low_read_btrace,
7680 linux_low_btrace_conf,
7688 linux_supports_range_stepping,
7689 linux_proc_pid_to_exec_file,
7690 linux_mntns_open_cloexec,
7692 linux_mntns_readlink,
7693 linux_breakpoint_kind_from_pc,
7694 linux_sw_breakpoint_from_kind,
7695 linux_proc_tid_get_name,
7696 linux_breakpoint_kind_from_current_state,
7697 linux_supports_software_single_step,
7698 linux_supports_catch_syscall,
7699 linux_get_ipa_tdesc_idx,
7702 #ifdef HAVE_LINUX_REGSETS
7704 initialize_regsets_info (struct regsets_info *info)
7706 for (info->num_regsets = 0;
7707 info->regsets[info->num_regsets].size >= 0;
7708 info->num_regsets++)
7714 initialize_low (void)
7716 struct sigaction sigchld_action;
7718 memset (&sigchld_action, 0, sizeof (sigchld_action));
7719 set_target_ops (&linux_target_ops);
7721 linux_ptrace_init_warnings ();
7723 sigchld_action.sa_handler = sigchld_handler;
7724 sigemptyset (&sigchld_action.sa_mask);
7725 sigchld_action.sa_flags = SA_RESTART;
7726 sigaction (SIGCHLD, &sigchld_action, NULL);
7728 initialize_low_arch ();
7730 linux_check_ptrace_features ();