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"
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 /* A list of all unknown processes which receive stop signals. Some
180 other process will presumably claim each of these as forked
181 children momentarily. */
183 struct simple_pid_list
185 /* The process ID. */
188 /* The status as reported by waitpid. */
192 struct simple_pid_list *next;
194 struct simple_pid_list *stopped_pids;
196 /* Trivial list manipulation functions to keep track of a list of new
197 stopped processes. */
200 add_to_pid_list (struct simple_pid_list **listp, int pid, int status)
202 struct simple_pid_list *new_pid = XNEW (struct simple_pid_list);
205 new_pid->status = status;
206 new_pid->next = *listp;
211 pull_pid_from_list (struct simple_pid_list **listp, int pid, int *statusp)
213 struct simple_pid_list **p;
215 for (p = listp; *p != NULL; p = &(*p)->next)
216 if ((*p)->pid == pid)
218 struct simple_pid_list *next = (*p)->next;
220 *statusp = (*p)->status;
228 enum stopping_threads_kind
230 /* Not stopping threads presently. */
231 NOT_STOPPING_THREADS,
233 /* Stopping threads. */
236 /* Stopping and suspending threads. */
237 STOPPING_AND_SUSPENDING_THREADS
240 /* This is set while stop_all_lwps is in effect. */
241 enum stopping_threads_kind stopping_threads = NOT_STOPPING_THREADS;
243 /* FIXME make into a target method? */
244 int using_threads = 1;
246 /* True if we're presently stabilizing threads (moving them out of
248 static int stabilizing_threads;
250 static void linux_resume_one_lwp (struct lwp_info *lwp,
251 int step, int signal, siginfo_t *info);
252 static void linux_resume (struct thread_resume *resume_info, size_t n);
253 static void stop_all_lwps (int suspend, struct lwp_info *except);
254 static void unstop_all_lwps (int unsuspend, struct lwp_info *except);
255 static int linux_wait_for_event_filtered (ptid_t wait_ptid, ptid_t filter_ptid,
256 int *wstat, int options);
257 static int linux_wait_for_event (ptid_t ptid, int *wstat, int options);
258 static struct lwp_info *add_lwp (ptid_t ptid);
259 static void linux_mourn (struct process_info *process);
260 static int linux_stopped_by_watchpoint (void);
261 static void mark_lwp_dead (struct lwp_info *lwp, int wstat);
262 static int lwp_is_marked_dead (struct lwp_info *lwp);
263 static void proceed_all_lwps (void);
264 static int finish_step_over (struct lwp_info *lwp);
265 static int kill_lwp (unsigned long lwpid, int signo);
266 static void enqueue_pending_signal (struct lwp_info *lwp, int signal, siginfo_t *info);
267 static void complete_ongoing_step_over (void);
268 static int linux_low_ptrace_options (int attached);
270 /* When the event-loop is doing a step-over, this points at the thread
272 ptid_t step_over_bkpt;
274 /* True if the low target can hardware single-step. */
277 can_hardware_single_step (void)
279 if (the_low_target.supports_hardware_single_step != NULL)
280 return the_low_target.supports_hardware_single_step ();
285 /* True if the low target can software single-step. Such targets
286 implement the GET_NEXT_PCS callback. */
289 can_software_single_step (void)
291 return (the_low_target.get_next_pcs != NULL);
294 /* True if the low target supports memory breakpoints. If so, we'll
295 have a GET_PC implementation. */
298 supports_breakpoints (void)
300 return (the_low_target.get_pc != NULL);
303 /* Returns true if this target can support fast tracepoints. This
304 does not mean that the in-process agent has been loaded in the
308 supports_fast_tracepoints (void)
310 return the_low_target.install_fast_tracepoint_jump_pad != NULL;
313 /* True if LWP is stopped in its stepping range. */
316 lwp_in_step_range (struct lwp_info *lwp)
318 CORE_ADDR pc = lwp->stop_pc;
320 return (pc >= lwp->step_range_start && pc < lwp->step_range_end);
323 struct pending_signals
327 struct pending_signals *prev;
330 /* The read/write ends of the pipe registered as waitable file in the
332 static int linux_event_pipe[2] = { -1, -1 };
334 /* True if we're currently in async mode. */
335 #define target_is_async_p() (linux_event_pipe[0] != -1)
337 static void send_sigstop (struct lwp_info *lwp);
338 static void wait_for_sigstop (void);
340 /* Return non-zero if HEADER is a 64-bit ELF file. */
343 elf_64_header_p (const Elf64_Ehdr *header, unsigned int *machine)
345 if (header->e_ident[EI_MAG0] == ELFMAG0
346 && header->e_ident[EI_MAG1] == ELFMAG1
347 && header->e_ident[EI_MAG2] == ELFMAG2
348 && header->e_ident[EI_MAG3] == ELFMAG3)
350 *machine = header->e_machine;
351 return header->e_ident[EI_CLASS] == ELFCLASS64;
358 /* Return non-zero if FILE is a 64-bit ELF file,
359 zero if the file is not a 64-bit ELF file,
360 and -1 if the file is not accessible or doesn't exist. */
363 elf_64_file_p (const char *file, unsigned int *machine)
368 fd = open (file, O_RDONLY);
372 if (read (fd, &header, sizeof (header)) != sizeof (header))
379 return elf_64_header_p (&header, machine);
382 /* Accepts an integer PID; Returns true if the executable PID is
383 running is a 64-bit ELF file.. */
386 linux_pid_exe_is_elf_64_file (int pid, unsigned int *machine)
390 sprintf (file, "/proc/%d/exe", pid);
391 return elf_64_file_p (file, machine);
395 delete_lwp (struct lwp_info *lwp)
397 struct thread_info *thr = get_lwp_thread (lwp);
400 debug_printf ("deleting %ld\n", lwpid_of (thr));
403 free (lwp->arch_private);
407 /* Add a process to the common process list, and set its private
410 static struct process_info *
411 linux_add_process (int pid, int attached)
413 struct process_info *proc;
415 proc = add_process (pid, attached);
416 proc->priv = XCNEW (struct process_info_private);
418 if (the_low_target.new_process != NULL)
419 proc->priv->arch_private = the_low_target.new_process ();
424 static CORE_ADDR get_pc (struct lwp_info *lwp);
426 /* Call the target arch_setup function on the current thread. */
429 linux_arch_setup (void)
431 the_low_target.arch_setup ();
434 /* Call the target arch_setup function on THREAD. */
437 linux_arch_setup_thread (struct thread_info *thread)
439 struct thread_info *saved_thread;
441 saved_thread = current_thread;
442 current_thread = thread;
446 current_thread = saved_thread;
449 /* Handle a GNU/Linux extended wait response. If we see a clone,
450 fork, or vfork event, we need to add the new LWP to our list
451 (and return 0 so as not to report the trap to higher layers).
452 If we see an exec event, we will modify ORIG_EVENT_LWP to point
453 to a new LWP representing the new program. */
456 handle_extended_wait (struct lwp_info **orig_event_lwp, int wstat)
458 struct lwp_info *event_lwp = *orig_event_lwp;
459 int event = linux_ptrace_get_extended_event (wstat);
460 struct thread_info *event_thr = get_lwp_thread (event_lwp);
461 struct lwp_info *new_lwp;
463 gdb_assert (event_lwp->waitstatus.kind == TARGET_WAITKIND_IGNORE);
465 /* All extended events we currently use are mid-syscall. Only
466 PTRACE_EVENT_STOP is delivered more like a signal-stop, but
467 you have to be using PTRACE_SEIZE to get that. */
468 event_lwp->syscall_state = TARGET_WAITKIND_SYSCALL_ENTRY;
470 if ((event == PTRACE_EVENT_FORK) || (event == PTRACE_EVENT_VFORK)
471 || (event == PTRACE_EVENT_CLONE))
474 unsigned long new_pid;
477 /* Get the pid of the new lwp. */
478 ptrace (PTRACE_GETEVENTMSG, lwpid_of (event_thr), (PTRACE_TYPE_ARG3) 0,
481 /* If we haven't already seen the new PID stop, wait for it now. */
482 if (!pull_pid_from_list (&stopped_pids, new_pid, &status))
484 /* The new child has a pending SIGSTOP. We can't affect it until it
485 hits the SIGSTOP, but we're already attached. */
487 ret = my_waitpid (new_pid, &status, __WALL);
490 perror_with_name ("waiting for new child");
491 else if (ret != new_pid)
492 warning ("wait returned unexpected PID %d", ret);
493 else if (!WIFSTOPPED (status))
494 warning ("wait returned unexpected status 0x%x", status);
497 if (event == PTRACE_EVENT_FORK || event == PTRACE_EVENT_VFORK)
499 struct process_info *parent_proc;
500 struct process_info *child_proc;
501 struct lwp_info *child_lwp;
502 struct thread_info *child_thr;
503 struct target_desc *tdesc;
505 ptid = ptid_build (new_pid, new_pid, 0);
509 debug_printf ("HEW: Got fork event from LWP %ld, "
511 ptid_get_lwp (ptid_of (event_thr)),
512 ptid_get_pid (ptid));
515 /* Add the new process to the tables and clone the breakpoint
516 lists of the parent. We need to do this even if the new process
517 will be detached, since we will need the process object and the
518 breakpoints to remove any breakpoints from memory when we
519 detach, and the client side will access registers. */
520 child_proc = linux_add_process (new_pid, 0);
521 gdb_assert (child_proc != NULL);
522 child_lwp = add_lwp (ptid);
523 gdb_assert (child_lwp != NULL);
524 child_lwp->stopped = 1;
525 child_lwp->must_set_ptrace_flags = 1;
526 child_lwp->status_pending_p = 0;
527 child_thr = get_lwp_thread (child_lwp);
528 child_thr->last_resume_kind = resume_stop;
529 child_thr->last_status.kind = TARGET_WAITKIND_STOPPED;
531 /* If we're suspending all threads, leave this one suspended
533 if (stopping_threads == STOPPING_AND_SUSPENDING_THREADS)
536 debug_printf ("HEW: leaving child suspended\n");
537 child_lwp->suspended = 1;
540 parent_proc = get_thread_process (event_thr);
541 child_proc->attached = parent_proc->attached;
542 clone_all_breakpoints (&child_proc->breakpoints,
543 &child_proc->raw_breakpoints,
544 parent_proc->breakpoints);
546 tdesc = XNEW (struct target_desc);
547 copy_target_description (tdesc, parent_proc->tdesc);
548 child_proc->tdesc = tdesc;
550 /* Clone arch-specific process data. */
551 if (the_low_target.new_fork != NULL)
552 the_low_target.new_fork (parent_proc, child_proc);
554 /* Save fork info in the parent thread. */
555 if (event == PTRACE_EVENT_FORK)
556 event_lwp->waitstatus.kind = TARGET_WAITKIND_FORKED;
557 else if (event == PTRACE_EVENT_VFORK)
558 event_lwp->waitstatus.kind = TARGET_WAITKIND_VFORKED;
560 event_lwp->waitstatus.value.related_pid = ptid;
562 /* The status_pending field contains bits denoting the
563 extended event, so when the pending event is handled,
564 the handler will look at lwp->waitstatus. */
565 event_lwp->status_pending_p = 1;
566 event_lwp->status_pending = wstat;
568 /* Report the event. */
573 debug_printf ("HEW: Got clone event "
574 "from LWP %ld, new child is LWP %ld\n",
575 lwpid_of (event_thr), new_pid);
577 ptid = ptid_build (pid_of (event_thr), new_pid, 0);
578 new_lwp = add_lwp (ptid);
580 /* Either we're going to immediately resume the new thread
581 or leave it stopped. linux_resume_one_lwp is a nop if it
582 thinks the thread is currently running, so set this first
583 before calling linux_resume_one_lwp. */
584 new_lwp->stopped = 1;
586 /* If we're suspending all threads, leave this one suspended
588 if (stopping_threads == STOPPING_AND_SUSPENDING_THREADS)
589 new_lwp->suspended = 1;
591 /* Normally we will get the pending SIGSTOP. But in some cases
592 we might get another signal delivered to the group first.
593 If we do get another signal, be sure not to lose it. */
594 if (WSTOPSIG (status) != SIGSTOP)
596 new_lwp->stop_expected = 1;
597 new_lwp->status_pending_p = 1;
598 new_lwp->status_pending = status;
600 else if (report_thread_events)
602 new_lwp->waitstatus.kind = TARGET_WAITKIND_THREAD_CREATED;
603 new_lwp->status_pending_p = 1;
604 new_lwp->status_pending = status;
607 /* Don't report the event. */
610 else if (event == PTRACE_EVENT_VFORK_DONE)
612 event_lwp->waitstatus.kind = TARGET_WAITKIND_VFORK_DONE;
614 /* Report the event. */
617 else if (event == PTRACE_EVENT_EXEC && report_exec_events)
619 struct process_info *proc;
620 VEC (int) *syscalls_to_catch;
626 debug_printf ("HEW: Got exec event from LWP %ld\n",
627 lwpid_of (event_thr));
630 /* Get the event ptid. */
631 event_ptid = ptid_of (event_thr);
632 event_pid = ptid_get_pid (event_ptid);
634 /* Save the syscall list from the execing process. */
635 proc = get_thread_process (event_thr);
636 syscalls_to_catch = proc->syscalls_to_catch;
637 proc->syscalls_to_catch = NULL;
639 /* Delete the execing process and all its threads. */
641 current_thread = NULL;
643 /* Create a new process/lwp/thread. */
644 proc = linux_add_process (event_pid, 0);
645 event_lwp = add_lwp (event_ptid);
646 event_thr = get_lwp_thread (event_lwp);
647 gdb_assert (current_thread == event_thr);
648 linux_arch_setup_thread (event_thr);
650 /* Set the event status. */
651 event_lwp->waitstatus.kind = TARGET_WAITKIND_EXECD;
652 event_lwp->waitstatus.value.execd_pathname
653 = xstrdup (linux_proc_pid_to_exec_file (lwpid_of (event_thr)));
655 /* Mark the exec status as pending. */
656 event_lwp->stopped = 1;
657 event_lwp->status_pending_p = 1;
658 event_lwp->status_pending = wstat;
659 event_thr->last_resume_kind = resume_continue;
660 event_thr->last_status.kind = TARGET_WAITKIND_IGNORE;
662 /* Update syscall state in the new lwp, effectively mid-syscall too. */
663 event_lwp->syscall_state = TARGET_WAITKIND_SYSCALL_ENTRY;
665 /* Restore the list to catch. Don't rely on the client, which is free
666 to avoid sending a new list when the architecture doesn't change.
667 Also, for ANY_SYSCALL, the architecture doesn't really matter. */
668 proc->syscalls_to_catch = syscalls_to_catch;
670 /* Report the event. */
671 *orig_event_lwp = event_lwp;
675 internal_error (__FILE__, __LINE__, _("unknown ptrace event %d"), event);
678 /* Return the PC as read from the regcache of LWP, without any
682 get_pc (struct lwp_info *lwp)
684 struct thread_info *saved_thread;
685 struct regcache *regcache;
688 if (the_low_target.get_pc == NULL)
691 saved_thread = current_thread;
692 current_thread = get_lwp_thread (lwp);
694 regcache = get_thread_regcache (current_thread, 1);
695 pc = (*the_low_target.get_pc) (regcache);
698 debug_printf ("pc is 0x%lx\n", (long) pc);
700 current_thread = saved_thread;
704 /* This function should only be called if LWP got a SYSCALL_SIGTRAP.
705 Fill *SYSNO with the syscall nr trapped. Fill *SYSRET with the
709 get_syscall_trapinfo (struct lwp_info *lwp, int *sysno, int *sysret)
711 struct thread_info *saved_thread;
712 struct regcache *regcache;
714 if (the_low_target.get_syscall_trapinfo == NULL)
716 /* If we cannot get the syscall trapinfo, report an unknown
717 system call number and -ENOSYS return value. */
718 *sysno = UNKNOWN_SYSCALL;
723 saved_thread = current_thread;
724 current_thread = get_lwp_thread (lwp);
726 regcache = get_thread_regcache (current_thread, 1);
727 (*the_low_target.get_syscall_trapinfo) (regcache, sysno, sysret);
731 debug_printf ("get_syscall_trapinfo sysno %d sysret %d\n",
735 current_thread = saved_thread;
738 static int check_stopped_by_watchpoint (struct lwp_info *child);
740 /* Called when the LWP stopped for a signal/trap. If it stopped for a
741 trap check what caused it (breakpoint, watchpoint, trace, etc.),
742 and save the result in the LWP's stop_reason field. If it stopped
743 for a breakpoint, decrement the PC if necessary on the lwp's
744 architecture. Returns true if we now have the LWP's stop PC. */
747 save_stop_reason (struct lwp_info *lwp)
750 CORE_ADDR sw_breakpoint_pc;
751 struct thread_info *saved_thread;
752 #if USE_SIGTRAP_SIGINFO
756 if (the_low_target.get_pc == NULL)
760 sw_breakpoint_pc = pc - the_low_target.decr_pc_after_break;
762 /* breakpoint_at reads from the current thread. */
763 saved_thread = current_thread;
764 current_thread = get_lwp_thread (lwp);
766 #if USE_SIGTRAP_SIGINFO
767 if (ptrace (PTRACE_GETSIGINFO, lwpid_of (current_thread),
768 (PTRACE_TYPE_ARG3) 0, &siginfo) == 0)
770 if (siginfo.si_signo == SIGTRAP)
772 if (GDB_ARCH_IS_TRAP_BRKPT (siginfo.si_code)
773 && GDB_ARCH_IS_TRAP_HWBKPT (siginfo.si_code))
775 /* The si_code is ambiguous on this arch -- check debug
777 if (!check_stopped_by_watchpoint (lwp))
778 lwp->stop_reason = TARGET_STOPPED_BY_SW_BREAKPOINT;
780 else if (GDB_ARCH_IS_TRAP_BRKPT (siginfo.si_code))
782 /* If we determine the LWP stopped for a SW breakpoint,
783 trust it. Particularly don't check watchpoint
784 registers, because at least on s390, we'd find
785 stopped-by-watchpoint as long as there's a watchpoint
787 lwp->stop_reason = TARGET_STOPPED_BY_SW_BREAKPOINT;
789 else if (GDB_ARCH_IS_TRAP_HWBKPT (siginfo.si_code))
791 /* This can indicate either a hardware breakpoint or
792 hardware watchpoint. Check debug registers. */
793 if (!check_stopped_by_watchpoint (lwp))
794 lwp->stop_reason = TARGET_STOPPED_BY_HW_BREAKPOINT;
796 else if (siginfo.si_code == TRAP_TRACE)
798 /* We may have single stepped an instruction that
799 triggered a watchpoint. In that case, on some
800 architectures (such as x86), instead of TRAP_HWBKPT,
801 si_code indicates TRAP_TRACE, and we need to check
802 the debug registers separately. */
803 if (!check_stopped_by_watchpoint (lwp))
804 lwp->stop_reason = TARGET_STOPPED_BY_SINGLE_STEP;
809 /* We may have just stepped a breakpoint instruction. E.g., in
810 non-stop mode, GDB first tells the thread A to step a range, and
811 then the user inserts a breakpoint inside the range. In that
812 case we need to report the breakpoint PC. */
813 if ((!lwp->stepping || lwp->stop_pc == sw_breakpoint_pc)
814 && (*the_low_target.breakpoint_at) (sw_breakpoint_pc))
815 lwp->stop_reason = TARGET_STOPPED_BY_SW_BREAKPOINT;
817 if (hardware_breakpoint_inserted_here (pc))
818 lwp->stop_reason = TARGET_STOPPED_BY_HW_BREAKPOINT;
820 if (lwp->stop_reason == TARGET_STOPPED_BY_NO_REASON)
821 check_stopped_by_watchpoint (lwp);
824 if (lwp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT)
828 struct thread_info *thr = get_lwp_thread (lwp);
830 debug_printf ("CSBB: %s stopped by software breakpoint\n",
831 target_pid_to_str (ptid_of (thr)));
834 /* Back up the PC if necessary. */
835 if (pc != sw_breakpoint_pc)
837 struct regcache *regcache
838 = get_thread_regcache (current_thread, 1);
839 (*the_low_target.set_pc) (regcache, sw_breakpoint_pc);
842 /* Update this so we record the correct stop PC below. */
843 pc = sw_breakpoint_pc;
845 else if (lwp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT)
849 struct thread_info *thr = get_lwp_thread (lwp);
851 debug_printf ("CSBB: %s stopped by hardware breakpoint\n",
852 target_pid_to_str (ptid_of (thr)));
855 else if (lwp->stop_reason == TARGET_STOPPED_BY_WATCHPOINT)
859 struct thread_info *thr = get_lwp_thread (lwp);
861 debug_printf ("CSBB: %s stopped by hardware watchpoint\n",
862 target_pid_to_str (ptid_of (thr)));
865 else if (lwp->stop_reason == TARGET_STOPPED_BY_SINGLE_STEP)
869 struct thread_info *thr = get_lwp_thread (lwp);
871 debug_printf ("CSBB: %s stopped by trace\n",
872 target_pid_to_str (ptid_of (thr)));
877 current_thread = saved_thread;
881 static struct lwp_info *
882 add_lwp (ptid_t ptid)
884 struct lwp_info *lwp;
886 lwp = XCNEW (struct lwp_info);
888 lwp->waitstatus.kind = TARGET_WAITKIND_IGNORE;
890 if (the_low_target.new_thread != NULL)
891 the_low_target.new_thread (lwp);
893 lwp->thread = add_thread (ptid, lwp);
898 /* Start an inferior process and returns its pid.
899 ALLARGS is a vector of program-name and args. */
902 linux_create_inferior (char *program, char **allargs)
904 struct lwp_info *new_lwp;
907 struct cleanup *restore_personality
908 = maybe_disable_address_space_randomization (disable_randomization);
910 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
916 perror_with_name ("fork");
921 ptrace (PTRACE_TRACEME, 0, (PTRACE_TYPE_ARG3) 0, (PTRACE_TYPE_ARG4) 0);
925 /* If gdbserver is connected to gdb via stdio, redirect the inferior's
926 stdout to stderr so that inferior i/o doesn't corrupt the connection.
927 Also, redirect stdin to /dev/null. */
928 if (remote_connection_is_stdio ())
931 open ("/dev/null", O_RDONLY);
933 if (write (2, "stdin/stdout redirected\n",
934 sizeof ("stdin/stdout redirected\n") - 1) < 0)
936 /* Errors ignored. */;
940 execv (program, allargs);
942 execvp (program, allargs);
944 fprintf (stderr, "Cannot exec %s: %s.\n", program,
950 do_cleanups (restore_personality);
952 linux_add_process (pid, 0);
954 ptid = ptid_build (pid, pid, 0);
955 new_lwp = add_lwp (ptid);
956 new_lwp->must_set_ptrace_flags = 1;
961 /* Implement the post_create_inferior target_ops method. */
964 linux_post_create_inferior (void)
966 struct lwp_info *lwp = get_thread_lwp (current_thread);
970 if (lwp->must_set_ptrace_flags)
972 struct process_info *proc = current_process ();
973 int options = linux_low_ptrace_options (proc->attached);
975 linux_enable_event_reporting (lwpid_of (current_thread), options);
976 lwp->must_set_ptrace_flags = 0;
980 /* Attach to an inferior process. Returns 0 on success, ERRNO on
984 linux_attach_lwp (ptid_t ptid)
986 struct lwp_info *new_lwp;
987 int lwpid = ptid_get_lwp (ptid);
989 if (ptrace (PTRACE_ATTACH, lwpid, (PTRACE_TYPE_ARG3) 0, (PTRACE_TYPE_ARG4) 0)
993 new_lwp = add_lwp (ptid);
995 /* We need to wait for SIGSTOP before being able to make the next
996 ptrace call on this LWP. */
997 new_lwp->must_set_ptrace_flags = 1;
999 if (linux_proc_pid_is_stopped (lwpid))
1002 debug_printf ("Attached to a stopped process\n");
1004 /* The process is definitely stopped. It is in a job control
1005 stop, unless the kernel predates the TASK_STOPPED /
1006 TASK_TRACED distinction, in which case it might be in a
1007 ptrace stop. Make sure it is in a ptrace stop; from there we
1008 can kill it, signal it, et cetera.
1010 First make sure there is a pending SIGSTOP. Since we are
1011 already attached, the process can not transition from stopped
1012 to running without a PTRACE_CONT; so we know this signal will
1013 go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
1014 probably already in the queue (unless this kernel is old
1015 enough to use TASK_STOPPED for ptrace stops); but since
1016 SIGSTOP is not an RT signal, it can only be queued once. */
1017 kill_lwp (lwpid, SIGSTOP);
1019 /* Finally, resume the stopped process. This will deliver the
1020 SIGSTOP (or a higher priority signal, just like normal
1021 PTRACE_ATTACH), which we'll catch later on. */
1022 ptrace (PTRACE_CONT, lwpid, (PTRACE_TYPE_ARG3) 0, (PTRACE_TYPE_ARG4) 0);
1025 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
1026 brings it to a halt.
1028 There are several cases to consider here:
1030 1) gdbserver has already attached to the process and is being notified
1031 of a new thread that is being created.
1032 In this case we should ignore that SIGSTOP and resume the
1033 process. This is handled below by setting stop_expected = 1,
1034 and the fact that add_thread sets last_resume_kind ==
1037 2) This is the first thread (the process thread), and we're attaching
1038 to it via attach_inferior.
1039 In this case we want the process thread to stop.
1040 This is handled by having linux_attach set last_resume_kind ==
1041 resume_stop after we return.
1043 If the pid we are attaching to is also the tgid, we attach to and
1044 stop all the existing threads. Otherwise, we attach to pid and
1045 ignore any other threads in the same group as this pid.
1047 3) GDB is connecting to gdbserver and is requesting an enumeration of all
1049 In this case we want the thread to stop.
1050 FIXME: This case is currently not properly handled.
1051 We should wait for the SIGSTOP but don't. Things work apparently
1052 because enough time passes between when we ptrace (ATTACH) and when
1053 gdb makes the next ptrace call on the thread.
1055 On the other hand, if we are currently trying to stop all threads, we
1056 should treat the new thread as if we had sent it a SIGSTOP. This works
1057 because we are guaranteed that the add_lwp call above added us to the
1058 end of the list, and so the new thread has not yet reached
1059 wait_for_sigstop (but will). */
1060 new_lwp->stop_expected = 1;
1065 /* Callback for linux_proc_attach_tgid_threads. Attach to PTID if not
1066 already attached. Returns true if a new LWP is found, false
1070 attach_proc_task_lwp_callback (ptid_t ptid)
1072 /* Is this a new thread? */
1073 if (find_thread_ptid (ptid) == NULL)
1075 int lwpid = ptid_get_lwp (ptid);
1079 debug_printf ("Found new lwp %d\n", lwpid);
1081 err = linux_attach_lwp (ptid);
1083 /* Be quiet if we simply raced with the thread exiting. EPERM
1084 is returned if the thread's task still exists, and is marked
1085 as exited or zombie, as well as other conditions, so in that
1086 case, confirm the status in /proc/PID/status. */
1088 || (err == EPERM && linux_proc_pid_is_gone (lwpid)))
1092 debug_printf ("Cannot attach to lwp %d: "
1093 "thread is gone (%d: %s)\n",
1094 lwpid, err, strerror (err));
1099 warning (_("Cannot attach to lwp %d: %s"),
1101 linux_ptrace_attach_fail_reason_string (ptid, err));
1109 static void async_file_mark (void);
1111 /* Attach to PID. If PID is the tgid, attach to it and all
1115 linux_attach (unsigned long pid)
1117 struct process_info *proc;
1118 struct thread_info *initial_thread;
1119 ptid_t ptid = ptid_build (pid, pid, 0);
1122 /* Attach to PID. We will check for other threads
1124 err = linux_attach_lwp (ptid);
1126 error ("Cannot attach to process %ld: %s",
1127 pid, linux_ptrace_attach_fail_reason_string (ptid, err));
1129 proc = linux_add_process (pid, 1);
1131 /* Don't ignore the initial SIGSTOP if we just attached to this
1132 process. It will be collected by wait shortly. */
1133 initial_thread = find_thread_ptid (ptid_build (pid, pid, 0));
1134 initial_thread->last_resume_kind = resume_stop;
1136 /* We must attach to every LWP. If /proc is mounted, use that to
1137 find them now. On the one hand, the inferior may be using raw
1138 clone instead of using pthreads. On the other hand, even if it
1139 is using pthreads, GDB may not be connected yet (thread_db needs
1140 to do symbol lookups, through qSymbol). Also, thread_db walks
1141 structures in the inferior's address space to find the list of
1142 threads/LWPs, and those structures may well be corrupted. Note
1143 that once thread_db is loaded, we'll still use it to list threads
1144 and associate pthread info with each LWP. */
1145 linux_proc_attach_tgid_threads (pid, attach_proc_task_lwp_callback);
1147 /* GDB will shortly read the xml target description for this
1148 process, to figure out the process' architecture. But the target
1149 description is only filled in when the first process/thread in
1150 the thread group reports its initial PTRACE_ATTACH SIGSTOP. Do
1151 that now, otherwise, if GDB is fast enough, it could read the
1152 target description _before_ that initial stop. */
1155 struct lwp_info *lwp;
1157 ptid_t pid_ptid = pid_to_ptid (pid);
1159 lwpid = linux_wait_for_event_filtered (pid_ptid, pid_ptid,
1161 gdb_assert (lwpid > 0);
1163 lwp = find_lwp_pid (pid_to_ptid (lwpid));
1165 if (!WIFSTOPPED (wstat) || WSTOPSIG (wstat) != SIGSTOP)
1167 lwp->status_pending_p = 1;
1168 lwp->status_pending = wstat;
1171 initial_thread->last_resume_kind = resume_continue;
1175 gdb_assert (proc->tdesc != NULL);
1188 second_thread_of_pid_p (struct inferior_list_entry *entry, void *args)
1190 struct counter *counter = (struct counter *) args;
1192 if (ptid_get_pid (entry->id) == counter->pid)
1194 if (++counter->count > 1)
1202 last_thread_of_process_p (int pid)
1204 struct counter counter = { pid , 0 };
1206 return (find_inferior (&all_threads,
1207 second_thread_of_pid_p, &counter) == NULL);
1213 linux_kill_one_lwp (struct lwp_info *lwp)
1215 struct thread_info *thr = get_lwp_thread (lwp);
1216 int pid = lwpid_of (thr);
1218 /* PTRACE_KILL is unreliable. After stepping into a signal handler,
1219 there is no signal context, and ptrace(PTRACE_KILL) (or
1220 ptrace(PTRACE_CONT, SIGKILL), pretty much the same) acts like
1221 ptrace(CONT, pid, 0,0) and just resumes the tracee. A better
1222 alternative is to kill with SIGKILL. We only need one SIGKILL
1223 per process, not one for each thread. But since we still support
1224 support debugging programs using raw clone without CLONE_THREAD,
1225 we send one for each thread. For years, we used PTRACE_KILL
1226 only, so we're being a bit paranoid about some old kernels where
1227 PTRACE_KILL might work better (dubious if there are any such, but
1228 that's why it's paranoia), so we try SIGKILL first, PTRACE_KILL
1229 second, and so we're fine everywhere. */
1232 kill_lwp (pid, SIGKILL);
1235 int save_errno = errno;
1237 debug_printf ("LKL: kill_lwp (SIGKILL) %s, 0, 0 (%s)\n",
1238 target_pid_to_str (ptid_of (thr)),
1239 save_errno ? strerror (save_errno) : "OK");
1243 ptrace (PTRACE_KILL, pid, (PTRACE_TYPE_ARG3) 0, (PTRACE_TYPE_ARG4) 0);
1246 int save_errno = errno;
1248 debug_printf ("LKL: PTRACE_KILL %s, 0, 0 (%s)\n",
1249 target_pid_to_str (ptid_of (thr)),
1250 save_errno ? strerror (save_errno) : "OK");
1254 /* Kill LWP and wait for it to die. */
1257 kill_wait_lwp (struct lwp_info *lwp)
1259 struct thread_info *thr = get_lwp_thread (lwp);
1260 int pid = ptid_get_pid (ptid_of (thr));
1261 int lwpid = ptid_get_lwp (ptid_of (thr));
1266 debug_printf ("kwl: killing lwp %d, for pid: %d\n", lwpid, pid);
1270 linux_kill_one_lwp (lwp);
1272 /* Make sure it died. Notes:
1274 - The loop is most likely unnecessary.
1276 - We don't use linux_wait_for_event as that could delete lwps
1277 while we're iterating over them. We're not interested in
1278 any pending status at this point, only in making sure all
1279 wait status on the kernel side are collected until the
1282 - We don't use __WALL here as the __WALL emulation relies on
1283 SIGCHLD, and killing a stopped process doesn't generate
1284 one, nor an exit status.
1286 res = my_waitpid (lwpid, &wstat, 0);
1287 if (res == -1 && errno == ECHILD)
1288 res = my_waitpid (lwpid, &wstat, __WCLONE);
1289 } while (res > 0 && WIFSTOPPED (wstat));
1291 /* Even if it was stopped, the child may have already disappeared.
1292 E.g., if it was killed by SIGKILL. */
1293 if (res < 0 && errno != ECHILD)
1294 perror_with_name ("kill_wait_lwp");
1297 /* Callback for `find_inferior'. Kills an lwp of a given process,
1298 except the leader. */
1301 kill_one_lwp_callback (struct inferior_list_entry *entry, void *args)
1303 struct thread_info *thread = (struct thread_info *) entry;
1304 struct lwp_info *lwp = get_thread_lwp (thread);
1305 int pid = * (int *) args;
1307 if (ptid_get_pid (entry->id) != pid)
1310 /* We avoid killing the first thread here, because of a Linux kernel (at
1311 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
1312 the children get a chance to be reaped, it will remain a zombie
1315 if (lwpid_of (thread) == pid)
1318 debug_printf ("lkop: is last of process %s\n",
1319 target_pid_to_str (entry->id));
1323 kill_wait_lwp (lwp);
1328 linux_kill (int pid)
1330 struct process_info *process;
1331 struct lwp_info *lwp;
1333 process = find_process_pid (pid);
1334 if (process == NULL)
1337 /* If we're killing a running inferior, make sure it is stopped
1338 first, as PTRACE_KILL will not work otherwise. */
1339 stop_all_lwps (0, NULL);
1341 find_inferior (&all_threads, kill_one_lwp_callback , &pid);
1343 /* See the comment in linux_kill_one_lwp. We did not kill the first
1344 thread in the list, so do so now. */
1345 lwp = find_lwp_pid (pid_to_ptid (pid));
1350 debug_printf ("lk_1: cannot find lwp for pid: %d\n",
1354 kill_wait_lwp (lwp);
1356 the_target->mourn (process);
1358 /* Since we presently can only stop all lwps of all processes, we
1359 need to unstop lwps of other processes. */
1360 unstop_all_lwps (0, NULL);
1364 /* Get pending signal of THREAD, for detaching purposes. This is the
1365 signal the thread last stopped for, which we need to deliver to the
1366 thread when detaching, otherwise, it'd be suppressed/lost. */
1369 get_detach_signal (struct thread_info *thread)
1371 enum gdb_signal signo = GDB_SIGNAL_0;
1373 struct lwp_info *lp = get_thread_lwp (thread);
1375 if (lp->status_pending_p)
1376 status = lp->status_pending;
1379 /* If the thread had been suspended by gdbserver, and it stopped
1380 cleanly, then it'll have stopped with SIGSTOP. But we don't
1381 want to deliver that SIGSTOP. */
1382 if (thread->last_status.kind != TARGET_WAITKIND_STOPPED
1383 || thread->last_status.value.sig == GDB_SIGNAL_0)
1386 /* Otherwise, we may need to deliver the signal we
1388 status = lp->last_status;
1391 if (!WIFSTOPPED (status))
1394 debug_printf ("GPS: lwp %s hasn't stopped: no pending signal\n",
1395 target_pid_to_str (ptid_of (thread)));
1399 /* Extended wait statuses aren't real SIGTRAPs. */
1400 if (WSTOPSIG (status) == SIGTRAP && linux_is_extended_waitstatus (status))
1403 debug_printf ("GPS: lwp %s had stopped with extended "
1404 "status: no pending signal\n",
1405 target_pid_to_str (ptid_of (thread)));
1409 signo = gdb_signal_from_host (WSTOPSIG (status));
1411 if (program_signals_p && !program_signals[signo])
1414 debug_printf ("GPS: lwp %s had signal %s, but it is in nopass state\n",
1415 target_pid_to_str (ptid_of (thread)),
1416 gdb_signal_to_string (signo));
1419 else if (!program_signals_p
1420 /* If we have no way to know which signals GDB does not
1421 want to have passed to the program, assume
1422 SIGTRAP/SIGINT, which is GDB's default. */
1423 && (signo == GDB_SIGNAL_TRAP || signo == GDB_SIGNAL_INT))
1426 debug_printf ("GPS: lwp %s had signal %s, "
1427 "but we don't know if we should pass it. "
1428 "Default to not.\n",
1429 target_pid_to_str (ptid_of (thread)),
1430 gdb_signal_to_string (signo));
1436 debug_printf ("GPS: lwp %s has pending signal %s: delivering it.\n",
1437 target_pid_to_str (ptid_of (thread)),
1438 gdb_signal_to_string (signo));
1440 return WSTOPSIG (status);
1445 linux_detach_one_lwp (struct inferior_list_entry *entry, void *args)
1447 struct thread_info *thread = (struct thread_info *) entry;
1448 struct lwp_info *lwp = get_thread_lwp (thread);
1449 int pid = * (int *) args;
1452 if (ptid_get_pid (entry->id) != pid)
1455 /* If there is a pending SIGSTOP, get rid of it. */
1456 if (lwp->stop_expected)
1459 debug_printf ("Sending SIGCONT to %s\n",
1460 target_pid_to_str (ptid_of (thread)));
1462 kill_lwp (lwpid_of (thread), SIGCONT);
1463 lwp->stop_expected = 0;
1466 /* Flush any pending changes to the process's registers. */
1467 regcache_invalidate_thread (thread);
1469 /* Pass on any pending signal for this thread. */
1470 sig = get_detach_signal (thread);
1472 /* Finally, let it resume. */
1473 if (the_low_target.prepare_to_resume != NULL)
1474 the_low_target.prepare_to_resume (lwp);
1475 if (ptrace (PTRACE_DETACH, lwpid_of (thread), (PTRACE_TYPE_ARG3) 0,
1476 (PTRACE_TYPE_ARG4) (long) sig) < 0)
1477 error (_("Can't detach %s: %s"),
1478 target_pid_to_str (ptid_of (thread)),
1486 linux_detach (int pid)
1488 struct process_info *process;
1490 process = find_process_pid (pid);
1491 if (process == NULL)
1494 /* As there's a step over already in progress, let it finish first,
1495 otherwise nesting a stabilize_threads operation on top gets real
1497 complete_ongoing_step_over ();
1499 /* Stop all threads before detaching. First, ptrace requires that
1500 the thread is stopped to sucessfully detach. Second, thread_db
1501 may need to uninstall thread event breakpoints from memory, which
1502 only works with a stopped process anyway. */
1503 stop_all_lwps (0, NULL);
1505 #ifdef USE_THREAD_DB
1506 thread_db_detach (process);
1509 /* Stabilize threads (move out of jump pads). */
1510 stabilize_threads ();
1512 find_inferior (&all_threads, linux_detach_one_lwp, &pid);
1514 the_target->mourn (process);
1516 /* Since we presently can only stop all lwps of all processes, we
1517 need to unstop lwps of other processes. */
1518 unstop_all_lwps (0, NULL);
1522 /* Remove all LWPs that belong to process PROC from the lwp list. */
1525 delete_lwp_callback (struct inferior_list_entry *entry, void *proc)
1527 struct thread_info *thread = (struct thread_info *) entry;
1528 struct lwp_info *lwp = get_thread_lwp (thread);
1529 struct process_info *process = (struct process_info *) proc;
1531 if (pid_of (thread) == pid_of (process))
1538 linux_mourn (struct process_info *process)
1540 struct process_info_private *priv;
1542 #ifdef USE_THREAD_DB
1543 thread_db_mourn (process);
1546 find_inferior (&all_threads, delete_lwp_callback, process);
1548 /* Freeing all private data. */
1549 priv = process->priv;
1550 free (priv->arch_private);
1552 process->priv = NULL;
1554 remove_process (process);
1558 linux_join (int pid)
1563 ret = my_waitpid (pid, &status, 0);
1564 if (WIFEXITED (status) || WIFSIGNALED (status))
1566 } while (ret != -1 || errno != ECHILD);
1569 /* Return nonzero if the given thread is still alive. */
1571 linux_thread_alive (ptid_t ptid)
1573 struct lwp_info *lwp = find_lwp_pid (ptid);
1575 /* We assume we always know if a thread exits. If a whole process
1576 exited but we still haven't been able to report it to GDB, we'll
1577 hold on to the last lwp of the dead process. */
1579 return !lwp_is_marked_dead (lwp);
1584 /* Return 1 if this lwp still has an interesting status pending. If
1585 not (e.g., it had stopped for a breakpoint that is gone), return
1589 thread_still_has_status_pending_p (struct thread_info *thread)
1591 struct lwp_info *lp = get_thread_lwp (thread);
1593 if (!lp->status_pending_p)
1596 if (thread->last_resume_kind != resume_stop
1597 && (lp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT
1598 || lp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT))
1600 struct thread_info *saved_thread;
1604 gdb_assert (lp->last_status != 0);
1608 saved_thread = current_thread;
1609 current_thread = thread;
1611 if (pc != lp->stop_pc)
1614 debug_printf ("PC of %ld changed\n",
1619 #if !USE_SIGTRAP_SIGINFO
1620 else if (lp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT
1621 && !(*the_low_target.breakpoint_at) (pc))
1624 debug_printf ("previous SW breakpoint of %ld gone\n",
1628 else if (lp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT
1629 && !hardware_breakpoint_inserted_here (pc))
1632 debug_printf ("previous HW breakpoint of %ld gone\n",
1638 current_thread = saved_thread;
1643 debug_printf ("discarding pending breakpoint status\n");
1644 lp->status_pending_p = 0;
1652 /* Returns true if LWP is resumed from the client's perspective. */
1655 lwp_resumed (struct lwp_info *lwp)
1657 struct thread_info *thread = get_lwp_thread (lwp);
1659 if (thread->last_resume_kind != resume_stop)
1662 /* Did gdb send us a `vCont;t', but we haven't reported the
1663 corresponding stop to gdb yet? If so, the thread is still
1664 resumed/running from gdb's perspective. */
1665 if (thread->last_resume_kind == resume_stop
1666 && thread->last_status.kind == TARGET_WAITKIND_IGNORE)
1672 /* Return 1 if this lwp has an interesting status pending. */
1674 status_pending_p_callback (struct inferior_list_entry *entry, void *arg)
1676 struct thread_info *thread = (struct thread_info *) entry;
1677 struct lwp_info *lp = get_thread_lwp (thread);
1678 ptid_t ptid = * (ptid_t *) arg;
1680 /* Check if we're only interested in events from a specific process
1681 or a specific LWP. */
1682 if (!ptid_match (ptid_of (thread), ptid))
1685 if (!lwp_resumed (lp))
1688 if (lp->status_pending_p
1689 && !thread_still_has_status_pending_p (thread))
1691 linux_resume_one_lwp (lp, lp->stepping, GDB_SIGNAL_0, NULL);
1695 return lp->status_pending_p;
1699 same_lwp (struct inferior_list_entry *entry, void *data)
1701 ptid_t ptid = *(ptid_t *) data;
1704 if (ptid_get_lwp (ptid) != 0)
1705 lwp = ptid_get_lwp (ptid);
1707 lwp = ptid_get_pid (ptid);
1709 if (ptid_get_lwp (entry->id) == lwp)
1716 find_lwp_pid (ptid_t ptid)
1718 struct inferior_list_entry *thread
1719 = find_inferior (&all_threads, same_lwp, &ptid);
1724 return get_thread_lwp ((struct thread_info *) thread);
1727 /* Return the number of known LWPs in the tgid given by PID. */
1732 struct inferior_list_entry *inf, *tmp;
1735 ALL_INFERIORS (&all_threads, inf, tmp)
1737 if (ptid_get_pid (inf->id) == pid)
1744 /* The arguments passed to iterate_over_lwps. */
1746 struct iterate_over_lwps_args
1748 /* The FILTER argument passed to iterate_over_lwps. */
1751 /* The CALLBACK argument passed to iterate_over_lwps. */
1752 iterate_over_lwps_ftype *callback;
1754 /* The DATA argument passed to iterate_over_lwps. */
1758 /* Callback for find_inferior used by iterate_over_lwps to filter
1759 calls to the callback supplied to that function. Returning a
1760 nonzero value causes find_inferiors to stop iterating and return
1761 the current inferior_list_entry. Returning zero indicates that
1762 find_inferiors should continue iterating. */
1765 iterate_over_lwps_filter (struct inferior_list_entry *entry, void *args_p)
1767 struct iterate_over_lwps_args *args
1768 = (struct iterate_over_lwps_args *) args_p;
1770 if (ptid_match (entry->id, args->filter))
1772 struct thread_info *thr = (struct thread_info *) entry;
1773 struct lwp_info *lwp = get_thread_lwp (thr);
1775 return (*args->callback) (lwp, args->data);
1781 /* See nat/linux-nat.h. */
1784 iterate_over_lwps (ptid_t filter,
1785 iterate_over_lwps_ftype callback,
1788 struct iterate_over_lwps_args args = {filter, callback, data};
1789 struct inferior_list_entry *entry;
1791 entry = find_inferior (&all_threads, iterate_over_lwps_filter, &args);
1795 return get_thread_lwp ((struct thread_info *) entry);
1798 /* Detect zombie thread group leaders, and "exit" them. We can't reap
1799 their exits until all other threads in the group have exited. */
1802 check_zombie_leaders (void)
1804 struct process_info *proc, *tmp;
1806 ALL_PROCESSES (proc, tmp)
1808 pid_t leader_pid = pid_of (proc);
1809 struct lwp_info *leader_lp;
1811 leader_lp = find_lwp_pid (pid_to_ptid (leader_pid));
1814 debug_printf ("leader_pid=%d, leader_lp!=NULL=%d, "
1815 "num_lwps=%d, zombie=%d\n",
1816 leader_pid, leader_lp!= NULL, num_lwps (leader_pid),
1817 linux_proc_pid_is_zombie (leader_pid));
1819 if (leader_lp != NULL && !leader_lp->stopped
1820 /* Check if there are other threads in the group, as we may
1821 have raced with the inferior simply exiting. */
1822 && !last_thread_of_process_p (leader_pid)
1823 && linux_proc_pid_is_zombie (leader_pid))
1825 /* A leader zombie can mean one of two things:
1827 - It exited, and there's an exit status pending
1828 available, or only the leader exited (not the whole
1829 program). In the latter case, we can't waitpid the
1830 leader's exit status until all other threads are gone.
1832 - There are 3 or more threads in the group, and a thread
1833 other than the leader exec'd. On an exec, the Linux
1834 kernel destroys all other threads (except the execing
1835 one) in the thread group, and resets the execing thread's
1836 tid to the tgid. No exit notification is sent for the
1837 execing thread -- from the ptracer's perspective, it
1838 appears as though the execing thread just vanishes.
1839 Until we reap all other threads except the leader and the
1840 execing thread, the leader will be zombie, and the
1841 execing thread will be in `D (disc sleep)'. As soon as
1842 all other threads are reaped, the execing thread changes
1843 it's tid to the tgid, and the previous (zombie) leader
1844 vanishes, giving place to the "new" leader. We could try
1845 distinguishing the exit and exec cases, by waiting once
1846 more, and seeing if something comes out, but it doesn't
1847 sound useful. The previous leader _does_ go away, and
1848 we'll re-add the new one once we see the exec event
1849 (which is just the same as what would happen if the
1850 previous leader did exit voluntarily before some other
1855 "CZL: Thread group leader %d zombie "
1856 "(it exited, or another thread execd).\n",
1859 delete_lwp (leader_lp);
1864 /* Callback for `find_inferior'. Returns the first LWP that is not
1865 stopped. ARG is a PTID filter. */
1868 not_stopped_callback (struct inferior_list_entry *entry, void *arg)
1870 struct thread_info *thr = (struct thread_info *) entry;
1871 struct lwp_info *lwp;
1872 ptid_t filter = *(ptid_t *) arg;
1874 if (!ptid_match (ptid_of (thr), filter))
1877 lwp = get_thread_lwp (thr);
1884 /* Increment LWP's suspend count. */
1887 lwp_suspended_inc (struct lwp_info *lwp)
1891 if (debug_threads && lwp->suspended > 4)
1893 struct thread_info *thread = get_lwp_thread (lwp);
1895 debug_printf ("LWP %ld has a suspiciously high suspend count,"
1896 " suspended=%d\n", lwpid_of (thread), lwp->suspended);
1900 /* Decrement LWP's suspend count. */
1903 lwp_suspended_decr (struct lwp_info *lwp)
1907 if (lwp->suspended < 0)
1909 struct thread_info *thread = get_lwp_thread (lwp);
1911 internal_error (__FILE__, __LINE__,
1912 "unsuspend LWP %ld, suspended=%d\n", lwpid_of (thread),
1917 /* This function should only be called if the LWP got a SIGTRAP.
1919 Handle any tracepoint steps or hits. Return true if a tracepoint
1920 event was handled, 0 otherwise. */
1923 handle_tracepoints (struct lwp_info *lwp)
1925 struct thread_info *tinfo = get_lwp_thread (lwp);
1926 int tpoint_related_event = 0;
1928 gdb_assert (lwp->suspended == 0);
1930 /* If this tracepoint hit causes a tracing stop, we'll immediately
1931 uninsert tracepoints. To do this, we temporarily pause all
1932 threads, unpatch away, and then unpause threads. We need to make
1933 sure the unpausing doesn't resume LWP too. */
1934 lwp_suspended_inc (lwp);
1936 /* And we need to be sure that any all-threads-stopping doesn't try
1937 to move threads out of the jump pads, as it could deadlock the
1938 inferior (LWP could be in the jump pad, maybe even holding the
1941 /* Do any necessary step collect actions. */
1942 tpoint_related_event |= tracepoint_finished_step (tinfo, lwp->stop_pc);
1944 tpoint_related_event |= handle_tracepoint_bkpts (tinfo, lwp->stop_pc);
1946 /* See if we just hit a tracepoint and do its main collect
1948 tpoint_related_event |= tracepoint_was_hit (tinfo, lwp->stop_pc);
1950 lwp_suspended_decr (lwp);
1952 gdb_assert (lwp->suspended == 0);
1953 gdb_assert (!stabilizing_threads || lwp->collecting_fast_tracepoint);
1955 if (tpoint_related_event)
1958 debug_printf ("got a tracepoint event\n");
1965 /* Convenience wrapper. Returns true if LWP is presently collecting a
1969 linux_fast_tracepoint_collecting (struct lwp_info *lwp,
1970 struct fast_tpoint_collect_status *status)
1972 CORE_ADDR thread_area;
1973 struct thread_info *thread = get_lwp_thread (lwp);
1975 if (the_low_target.get_thread_area == NULL)
1978 /* Get the thread area address. This is used to recognize which
1979 thread is which when tracing with the in-process agent library.
1980 We don't read anything from the address, and treat it as opaque;
1981 it's the address itself that we assume is unique per-thread. */
1982 if ((*the_low_target.get_thread_area) (lwpid_of (thread), &thread_area) == -1)
1985 return fast_tracepoint_collecting (thread_area, lwp->stop_pc, status);
1988 /* The reason we resume in the caller, is because we want to be able
1989 to pass lwp->status_pending as WSTAT, and we need to clear
1990 status_pending_p before resuming, otherwise, linux_resume_one_lwp
1991 refuses to resume. */
1994 maybe_move_out_of_jump_pad (struct lwp_info *lwp, int *wstat)
1996 struct thread_info *saved_thread;
1998 saved_thread = current_thread;
1999 current_thread = get_lwp_thread (lwp);
2002 || (WIFSTOPPED (*wstat) && WSTOPSIG (*wstat) != SIGTRAP))
2003 && supports_fast_tracepoints ()
2004 && agent_loaded_p ())
2006 struct fast_tpoint_collect_status status;
2010 debug_printf ("Checking whether LWP %ld needs to move out of the "
2012 lwpid_of (current_thread));
2014 r = linux_fast_tracepoint_collecting (lwp, &status);
2017 || (WSTOPSIG (*wstat) != SIGILL
2018 && WSTOPSIG (*wstat) != SIGFPE
2019 && WSTOPSIG (*wstat) != SIGSEGV
2020 && WSTOPSIG (*wstat) != SIGBUS))
2022 lwp->collecting_fast_tracepoint = r;
2026 if (r == 1 && lwp->exit_jump_pad_bkpt == NULL)
2028 /* Haven't executed the original instruction yet.
2029 Set breakpoint there, and wait till it's hit,
2030 then single-step until exiting the jump pad. */
2031 lwp->exit_jump_pad_bkpt
2032 = set_breakpoint_at (status.adjusted_insn_addr, NULL);
2036 debug_printf ("Checking whether LWP %ld needs to move out of "
2037 "the jump pad...it does\n",
2038 lwpid_of (current_thread));
2039 current_thread = saved_thread;
2046 /* If we get a synchronous signal while collecting, *and*
2047 while executing the (relocated) original instruction,
2048 reset the PC to point at the tpoint address, before
2049 reporting to GDB. Otherwise, it's an IPA lib bug: just
2050 report the signal to GDB, and pray for the best. */
2052 lwp->collecting_fast_tracepoint = 0;
2055 && (status.adjusted_insn_addr <= lwp->stop_pc
2056 && lwp->stop_pc < status.adjusted_insn_addr_end))
2059 struct regcache *regcache;
2061 /* The si_addr on a few signals references the address
2062 of the faulting instruction. Adjust that as
2064 if ((WSTOPSIG (*wstat) == SIGILL
2065 || WSTOPSIG (*wstat) == SIGFPE
2066 || WSTOPSIG (*wstat) == SIGBUS
2067 || WSTOPSIG (*wstat) == SIGSEGV)
2068 && ptrace (PTRACE_GETSIGINFO, lwpid_of (current_thread),
2069 (PTRACE_TYPE_ARG3) 0, &info) == 0
2070 /* Final check just to make sure we don't clobber
2071 the siginfo of non-kernel-sent signals. */
2072 && (uintptr_t) info.si_addr == lwp->stop_pc)
2074 info.si_addr = (void *) (uintptr_t) status.tpoint_addr;
2075 ptrace (PTRACE_SETSIGINFO, lwpid_of (current_thread),
2076 (PTRACE_TYPE_ARG3) 0, &info);
2079 regcache = get_thread_regcache (current_thread, 1);
2080 (*the_low_target.set_pc) (regcache, status.tpoint_addr);
2081 lwp->stop_pc = status.tpoint_addr;
2083 /* Cancel any fast tracepoint lock this thread was
2085 force_unlock_trace_buffer ();
2088 if (lwp->exit_jump_pad_bkpt != NULL)
2091 debug_printf ("Cancelling fast exit-jump-pad: removing bkpt. "
2092 "stopping all threads momentarily.\n");
2094 stop_all_lwps (1, lwp);
2096 delete_breakpoint (lwp->exit_jump_pad_bkpt);
2097 lwp->exit_jump_pad_bkpt = NULL;
2099 unstop_all_lwps (1, lwp);
2101 gdb_assert (lwp->suspended >= 0);
2107 debug_printf ("Checking whether LWP %ld needs to move out of the "
2109 lwpid_of (current_thread));
2111 current_thread = saved_thread;
2115 /* Enqueue one signal in the "signals to report later when out of the
2119 enqueue_one_deferred_signal (struct lwp_info *lwp, int *wstat)
2121 struct pending_signals *p_sig;
2122 struct thread_info *thread = get_lwp_thread (lwp);
2125 debug_printf ("Deferring signal %d for LWP %ld.\n",
2126 WSTOPSIG (*wstat), lwpid_of (thread));
2130 struct pending_signals *sig;
2132 for (sig = lwp->pending_signals_to_report;
2135 debug_printf (" Already queued %d\n",
2138 debug_printf (" (no more currently queued signals)\n");
2141 /* Don't enqueue non-RT signals if they are already in the deferred
2142 queue. (SIGSTOP being the easiest signal to see ending up here
2144 if (WSTOPSIG (*wstat) < __SIGRTMIN)
2146 struct pending_signals *sig;
2148 for (sig = lwp->pending_signals_to_report;
2152 if (sig->signal == WSTOPSIG (*wstat))
2155 debug_printf ("Not requeuing already queued non-RT signal %d"
2164 p_sig = XCNEW (struct pending_signals);
2165 p_sig->prev = lwp->pending_signals_to_report;
2166 p_sig->signal = WSTOPSIG (*wstat);
2168 ptrace (PTRACE_GETSIGINFO, lwpid_of (thread), (PTRACE_TYPE_ARG3) 0,
2171 lwp->pending_signals_to_report = p_sig;
2174 /* Dequeue one signal from the "signals to report later when out of
2175 the jump pad" list. */
2178 dequeue_one_deferred_signal (struct lwp_info *lwp, int *wstat)
2180 struct thread_info *thread = get_lwp_thread (lwp);
2182 if (lwp->pending_signals_to_report != NULL)
2184 struct pending_signals **p_sig;
2186 p_sig = &lwp->pending_signals_to_report;
2187 while ((*p_sig)->prev != NULL)
2188 p_sig = &(*p_sig)->prev;
2190 *wstat = W_STOPCODE ((*p_sig)->signal);
2191 if ((*p_sig)->info.si_signo != 0)
2192 ptrace (PTRACE_SETSIGINFO, lwpid_of (thread), (PTRACE_TYPE_ARG3) 0,
2198 debug_printf ("Reporting deferred signal %d for LWP %ld.\n",
2199 WSTOPSIG (*wstat), lwpid_of (thread));
2203 struct pending_signals *sig;
2205 for (sig = lwp->pending_signals_to_report;
2208 debug_printf (" Still queued %d\n",
2211 debug_printf (" (no more queued signals)\n");
2220 /* Fetch the possibly triggered data watchpoint info and store it in
2223 On some archs, like x86, that use debug registers to set
2224 watchpoints, it's possible that the way to know which watched
2225 address trapped, is to check the register that is used to select
2226 which address to watch. Problem is, between setting the watchpoint
2227 and reading back which data address trapped, the user may change
2228 the set of watchpoints, and, as a consequence, GDB changes the
2229 debug registers in the inferior. To avoid reading back a stale
2230 stopped-data-address when that happens, we cache in LP the fact
2231 that a watchpoint trapped, and the corresponding data address, as
2232 soon as we see CHILD stop with a SIGTRAP. If GDB changes the debug
2233 registers meanwhile, we have the cached data we can rely on. */
2236 check_stopped_by_watchpoint (struct lwp_info *child)
2238 if (the_low_target.stopped_by_watchpoint != NULL)
2240 struct thread_info *saved_thread;
2242 saved_thread = current_thread;
2243 current_thread = get_lwp_thread (child);
2245 if (the_low_target.stopped_by_watchpoint ())
2247 child->stop_reason = TARGET_STOPPED_BY_WATCHPOINT;
2249 if (the_low_target.stopped_data_address != NULL)
2250 child->stopped_data_address
2251 = the_low_target.stopped_data_address ();
2253 child->stopped_data_address = 0;
2256 current_thread = saved_thread;
2259 return child->stop_reason == TARGET_STOPPED_BY_WATCHPOINT;
2262 /* Return the ptrace options that we want to try to enable. */
2265 linux_low_ptrace_options (int attached)
2270 options |= PTRACE_O_EXITKILL;
2272 if (report_fork_events)
2273 options |= PTRACE_O_TRACEFORK;
2275 if (report_vfork_events)
2276 options |= (PTRACE_O_TRACEVFORK | PTRACE_O_TRACEVFORKDONE);
2278 if (report_exec_events)
2279 options |= PTRACE_O_TRACEEXEC;
2281 options |= PTRACE_O_TRACESYSGOOD;
2286 /* Do low-level handling of the event, and check if we should go on
2287 and pass it to caller code. Return the affected lwp if we are, or
2290 static struct lwp_info *
2291 linux_low_filter_event (int lwpid, int wstat)
2293 struct lwp_info *child;
2294 struct thread_info *thread;
2295 int have_stop_pc = 0;
2297 child = find_lwp_pid (pid_to_ptid (lwpid));
2299 /* Check for stop events reported by a process we didn't already
2300 know about - anything not already in our LWP list.
2302 If we're expecting to receive stopped processes after
2303 fork, vfork, and clone events, then we'll just add the
2304 new one to our list and go back to waiting for the event
2305 to be reported - the stopped process might be returned
2306 from waitpid before or after the event is.
2308 But note the case of a non-leader thread exec'ing after the
2309 leader having exited, and gone from our lists (because
2310 check_zombie_leaders deleted it). The non-leader thread
2311 changes its tid to the tgid. */
2313 if (WIFSTOPPED (wstat) && child == NULL && WSTOPSIG (wstat) == SIGTRAP
2314 && linux_ptrace_get_extended_event (wstat) == PTRACE_EVENT_EXEC)
2318 /* A multi-thread exec after we had seen the leader exiting. */
2321 debug_printf ("LLW: Re-adding thread group leader LWP %d"
2322 "after exec.\n", lwpid);
2325 child_ptid = ptid_build (lwpid, lwpid, 0);
2326 child = add_lwp (child_ptid);
2328 current_thread = child->thread;
2331 /* If we didn't find a process, one of two things presumably happened:
2332 - A process we started and then detached from has exited. Ignore it.
2333 - A process we are controlling has forked and the new child's stop
2334 was reported to us by the kernel. Save its PID. */
2335 if (child == NULL && WIFSTOPPED (wstat))
2337 add_to_pid_list (&stopped_pids, lwpid, wstat);
2340 else if (child == NULL)
2343 thread = get_lwp_thread (child);
2347 child->last_status = wstat;
2349 /* Check if the thread has exited. */
2350 if ((WIFEXITED (wstat) || WIFSIGNALED (wstat)))
2353 debug_printf ("LLFE: %d exited.\n", lwpid);
2354 /* If there is at least one more LWP, then the exit signal was
2355 not the end of the debugged application and should be
2356 ignored, unless GDB wants to hear about thread exits. */
2357 if (report_thread_events
2358 || last_thread_of_process_p (pid_of (thread)))
2360 /* Since events are serialized to GDB core, and we can't
2361 report this one right now. Leave the status pending for
2362 the next time we're able to report it. */
2363 mark_lwp_dead (child, wstat);
2373 gdb_assert (WIFSTOPPED (wstat));
2375 if (WIFSTOPPED (wstat))
2377 struct process_info *proc;
2379 /* Architecture-specific setup after inferior is running. */
2380 proc = find_process_pid (pid_of (thread));
2381 if (proc->tdesc == NULL)
2385 /* This needs to happen after we have attached to the
2386 inferior and it is stopped for the first time, but
2387 before we access any inferior registers. */
2388 linux_arch_setup_thread (thread);
2392 /* The process is started, but GDBserver will do
2393 architecture-specific setup after the program stops at
2394 the first instruction. */
2395 child->status_pending_p = 1;
2396 child->status_pending = wstat;
2402 if (WIFSTOPPED (wstat) && child->must_set_ptrace_flags)
2404 struct process_info *proc = find_process_pid (pid_of (thread));
2405 int options = linux_low_ptrace_options (proc->attached);
2407 linux_enable_event_reporting (lwpid, options);
2408 child->must_set_ptrace_flags = 0;
2411 /* Always update syscall_state, even if it will be filtered later. */
2412 if (WIFSTOPPED (wstat) && WSTOPSIG (wstat) == SYSCALL_SIGTRAP)
2414 child->syscall_state
2415 = (child->syscall_state == TARGET_WAITKIND_SYSCALL_ENTRY
2416 ? TARGET_WAITKIND_SYSCALL_RETURN
2417 : TARGET_WAITKIND_SYSCALL_ENTRY);
2421 /* Almost all other ptrace-stops are known to be outside of system
2422 calls, with further exceptions in handle_extended_wait. */
2423 child->syscall_state = TARGET_WAITKIND_IGNORE;
2426 /* Be careful to not overwrite stop_pc until save_stop_reason is
2428 if (WIFSTOPPED (wstat) && WSTOPSIG (wstat) == SIGTRAP
2429 && linux_is_extended_waitstatus (wstat))
2431 child->stop_pc = get_pc (child);
2432 if (handle_extended_wait (&child, wstat))
2434 /* The event has been handled, so just return without
2440 if (WIFSTOPPED (wstat) && linux_wstatus_maybe_breakpoint (wstat))
2442 if (save_stop_reason (child))
2447 child->stop_pc = get_pc (child);
2449 if (WIFSTOPPED (wstat) && WSTOPSIG (wstat) == SIGSTOP
2450 && child->stop_expected)
2453 debug_printf ("Expected stop.\n");
2454 child->stop_expected = 0;
2456 if (thread->last_resume_kind == resume_stop)
2458 /* We want to report the stop to the core. Treat the
2459 SIGSTOP as a normal event. */
2461 debug_printf ("LLW: resume_stop SIGSTOP caught for %s.\n",
2462 target_pid_to_str (ptid_of (thread)));
2464 else if (stopping_threads != NOT_STOPPING_THREADS)
2466 /* Stopping threads. We don't want this SIGSTOP to end up
2469 debug_printf ("LLW: SIGSTOP caught for %s "
2470 "while stopping threads.\n",
2471 target_pid_to_str (ptid_of (thread)));
2476 /* This is a delayed SIGSTOP. Filter out the event. */
2478 debug_printf ("LLW: %s %s, 0, 0 (discard delayed SIGSTOP)\n",
2479 child->stepping ? "step" : "continue",
2480 target_pid_to_str (ptid_of (thread)));
2482 linux_resume_one_lwp (child, child->stepping, 0, NULL);
2487 child->status_pending_p = 1;
2488 child->status_pending = wstat;
2492 /* Resume LWPs that are currently stopped without any pending status
2493 to report, but are resumed from the core's perspective. */
2496 resume_stopped_resumed_lwps (struct inferior_list_entry *entry)
2498 struct thread_info *thread = (struct thread_info *) entry;
2499 struct lwp_info *lp = get_thread_lwp (thread);
2503 && !lp->status_pending_p
2504 && thread->last_status.kind == TARGET_WAITKIND_IGNORE)
2506 int step = thread->last_resume_kind == resume_step;
2509 debug_printf ("RSRL: resuming stopped-resumed LWP %s at %s: step=%d\n",
2510 target_pid_to_str (ptid_of (thread)),
2511 paddress (lp->stop_pc),
2514 linux_resume_one_lwp (lp, step, GDB_SIGNAL_0, NULL);
2518 /* Wait for an event from child(ren) WAIT_PTID, and return any that
2519 match FILTER_PTID (leaving others pending). The PTIDs can be:
2520 minus_one_ptid, to specify any child; a pid PTID, specifying all
2521 lwps of a thread group; or a PTID representing a single lwp. Store
2522 the stop status through the status pointer WSTAT. OPTIONS is
2523 passed to the waitpid call. Return 0 if no event was found and
2524 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
2525 was found. Return the PID of the stopped child otherwise. */
2528 linux_wait_for_event_filtered (ptid_t wait_ptid, ptid_t filter_ptid,
2529 int *wstatp, int options)
2531 struct thread_info *event_thread;
2532 struct lwp_info *event_child, *requested_child;
2533 sigset_t block_mask, prev_mask;
2536 /* N.B. event_thread points to the thread_info struct that contains
2537 event_child. Keep them in sync. */
2538 event_thread = NULL;
2540 requested_child = NULL;
2542 /* Check for a lwp with a pending status. */
2544 if (ptid_equal (filter_ptid, minus_one_ptid) || ptid_is_pid (filter_ptid))
2546 event_thread = (struct thread_info *)
2547 find_inferior (&all_threads, status_pending_p_callback, &filter_ptid);
2548 if (event_thread != NULL)
2549 event_child = get_thread_lwp (event_thread);
2550 if (debug_threads && event_thread)
2551 debug_printf ("Got a pending child %ld\n", lwpid_of (event_thread));
2553 else if (!ptid_equal (filter_ptid, null_ptid))
2555 requested_child = find_lwp_pid (filter_ptid);
2557 if (stopping_threads == NOT_STOPPING_THREADS
2558 && requested_child->status_pending_p
2559 && requested_child->collecting_fast_tracepoint)
2561 enqueue_one_deferred_signal (requested_child,
2562 &requested_child->status_pending);
2563 requested_child->status_pending_p = 0;
2564 requested_child->status_pending = 0;
2565 linux_resume_one_lwp (requested_child, 0, 0, NULL);
2568 if (requested_child->suspended
2569 && requested_child->status_pending_p)
2571 internal_error (__FILE__, __LINE__,
2572 "requesting an event out of a"
2573 " suspended child?");
2576 if (requested_child->status_pending_p)
2578 event_child = requested_child;
2579 event_thread = get_lwp_thread (event_child);
2583 if (event_child != NULL)
2586 debug_printf ("Got an event from pending child %ld (%04x)\n",
2587 lwpid_of (event_thread), event_child->status_pending);
2588 *wstatp = event_child->status_pending;
2589 event_child->status_pending_p = 0;
2590 event_child->status_pending = 0;
2591 current_thread = event_thread;
2592 return lwpid_of (event_thread);
2595 /* But if we don't find a pending event, we'll have to wait.
2597 We only enter this loop if no process has a pending wait status.
2598 Thus any action taken in response to a wait status inside this
2599 loop is responding as soon as we detect the status, not after any
2602 /* Make sure SIGCHLD is blocked until the sigsuspend below. Block
2603 all signals while here. */
2604 sigfillset (&block_mask);
2605 sigprocmask (SIG_BLOCK, &block_mask, &prev_mask);
2607 /* Always pull all events out of the kernel. We'll randomly select
2608 an event LWP out of all that have events, to prevent
2610 while (event_child == NULL)
2614 /* Always use -1 and WNOHANG, due to couple of a kernel/ptrace
2617 - If the thread group leader exits while other threads in the
2618 thread group still exist, waitpid(TGID, ...) hangs. That
2619 waitpid won't return an exit status until the other threads
2620 in the group are reaped.
2622 - When a non-leader thread execs, that thread just vanishes
2623 without reporting an exit (so we'd hang if we waited for it
2624 explicitly in that case). The exec event is reported to
2627 ret = my_waitpid (-1, wstatp, options | WNOHANG);
2630 debug_printf ("LWFE: waitpid(-1, ...) returned %d, %s\n",
2631 ret, errno ? strerror (errno) : "ERRNO-OK");
2637 debug_printf ("LLW: waitpid %ld received %s\n",
2638 (long) ret, status_to_str (*wstatp));
2641 /* Filter all events. IOW, leave all events pending. We'll
2642 randomly select an event LWP out of all that have events
2644 linux_low_filter_event (ret, *wstatp);
2645 /* Retry until nothing comes out of waitpid. A single
2646 SIGCHLD can indicate more than one child stopped. */
2650 /* Now that we've pulled all events out of the kernel, resume
2651 LWPs that don't have an interesting event to report. */
2652 if (stopping_threads == NOT_STOPPING_THREADS)
2653 for_each_inferior (&all_threads, resume_stopped_resumed_lwps);
2655 /* ... and find an LWP with a status to report to the core, if
2657 event_thread = (struct thread_info *)
2658 find_inferior (&all_threads, status_pending_p_callback, &filter_ptid);
2659 if (event_thread != NULL)
2661 event_child = get_thread_lwp (event_thread);
2662 *wstatp = event_child->status_pending;
2663 event_child->status_pending_p = 0;
2664 event_child->status_pending = 0;
2668 /* Check for zombie thread group leaders. Those can't be reaped
2669 until all other threads in the thread group are. */
2670 check_zombie_leaders ();
2672 /* If there are no resumed children left in the set of LWPs we
2673 want to wait for, bail. We can't just block in
2674 waitpid/sigsuspend, because lwps might have been left stopped
2675 in trace-stop state, and we'd be stuck forever waiting for
2676 their status to change (which would only happen if we resumed
2677 them). Even if WNOHANG is set, this return code is preferred
2678 over 0 (below), as it is more detailed. */
2679 if ((find_inferior (&all_threads,
2680 not_stopped_callback,
2681 &wait_ptid) == NULL))
2684 debug_printf ("LLW: exit (no unwaited-for LWP)\n");
2685 sigprocmask (SIG_SETMASK, &prev_mask, NULL);
2689 /* No interesting event to report to the caller. */
2690 if ((options & WNOHANG))
2693 debug_printf ("WNOHANG set, no event found\n");
2695 sigprocmask (SIG_SETMASK, &prev_mask, NULL);
2699 /* Block until we get an event reported with SIGCHLD. */
2701 debug_printf ("sigsuspend'ing\n");
2703 sigsuspend (&prev_mask);
2704 sigprocmask (SIG_SETMASK, &prev_mask, NULL);
2708 sigprocmask (SIG_SETMASK, &prev_mask, NULL);
2710 current_thread = event_thread;
2712 return lwpid_of (event_thread);
2715 /* Wait for an event from child(ren) PTID. PTIDs can be:
2716 minus_one_ptid, to specify any child; a pid PTID, specifying all
2717 lwps of a thread group; or a PTID representing a single lwp. Store
2718 the stop status through the status pointer WSTAT. OPTIONS is
2719 passed to the waitpid call. Return 0 if no event was found and
2720 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
2721 was found. Return the PID of the stopped child otherwise. */
2724 linux_wait_for_event (ptid_t ptid, int *wstatp, int options)
2726 return linux_wait_for_event_filtered (ptid, ptid, wstatp, options);
2729 /* Count the LWP's that have had events. */
2732 count_events_callback (struct inferior_list_entry *entry, void *data)
2734 struct thread_info *thread = (struct thread_info *) entry;
2735 struct lwp_info *lp = get_thread_lwp (thread);
2736 int *count = (int *) data;
2738 gdb_assert (count != NULL);
2740 /* Count only resumed LWPs that have an event pending. */
2741 if (thread->last_status.kind == TARGET_WAITKIND_IGNORE
2742 && lp->status_pending_p)
2748 /* Select the LWP (if any) that is currently being single-stepped. */
2751 select_singlestep_lwp_callback (struct inferior_list_entry *entry, void *data)
2753 struct thread_info *thread = (struct thread_info *) entry;
2754 struct lwp_info *lp = get_thread_lwp (thread);
2756 if (thread->last_status.kind == TARGET_WAITKIND_IGNORE
2757 && thread->last_resume_kind == resume_step
2758 && lp->status_pending_p)
2764 /* Select the Nth LWP that has had an event. */
2767 select_event_lwp_callback (struct inferior_list_entry *entry, void *data)
2769 struct thread_info *thread = (struct thread_info *) entry;
2770 struct lwp_info *lp = get_thread_lwp (thread);
2771 int *selector = (int *) data;
2773 gdb_assert (selector != NULL);
2775 /* Select only resumed LWPs that have an event pending. */
2776 if (thread->last_status.kind == TARGET_WAITKIND_IGNORE
2777 && lp->status_pending_p)
2778 if ((*selector)-- == 0)
2784 /* Select one LWP out of those that have events pending. */
2787 select_event_lwp (struct lwp_info **orig_lp)
2790 int random_selector;
2791 struct thread_info *event_thread = NULL;
2793 /* In all-stop, give preference to the LWP that is being
2794 single-stepped. There will be at most one, and it's the LWP that
2795 the core is most interested in. If we didn't do this, then we'd
2796 have to handle pending step SIGTRAPs somehow in case the core
2797 later continues the previously-stepped thread, otherwise we'd
2798 report the pending SIGTRAP, and the core, not having stepped the
2799 thread, wouldn't understand what the trap was for, and therefore
2800 would report it to the user as a random signal. */
2804 = (struct thread_info *) find_inferior (&all_threads,
2805 select_singlestep_lwp_callback,
2807 if (event_thread != NULL)
2810 debug_printf ("SEL: Select single-step %s\n",
2811 target_pid_to_str (ptid_of (event_thread)));
2814 if (event_thread == NULL)
2816 /* No single-stepping LWP. Select one at random, out of those
2817 which have had events. */
2819 /* First see how many events we have. */
2820 find_inferior (&all_threads, count_events_callback, &num_events);
2821 gdb_assert (num_events > 0);
2823 /* Now randomly pick a LWP out of those that have had
2825 random_selector = (int)
2826 ((num_events * (double) rand ()) / (RAND_MAX + 1.0));
2828 if (debug_threads && num_events > 1)
2829 debug_printf ("SEL: Found %d SIGTRAP events, selecting #%d\n",
2830 num_events, random_selector);
2833 = (struct thread_info *) find_inferior (&all_threads,
2834 select_event_lwp_callback,
2838 if (event_thread != NULL)
2840 struct lwp_info *event_lp = get_thread_lwp (event_thread);
2842 /* Switch the event LWP. */
2843 *orig_lp = event_lp;
2847 /* Decrement the suspend count of an LWP. */
2850 unsuspend_one_lwp (struct inferior_list_entry *entry, void *except)
2852 struct thread_info *thread = (struct thread_info *) entry;
2853 struct lwp_info *lwp = get_thread_lwp (thread);
2855 /* Ignore EXCEPT. */
2859 lwp_suspended_decr (lwp);
2863 /* Decrement the suspend count of all LWPs, except EXCEPT, if non
2867 unsuspend_all_lwps (struct lwp_info *except)
2869 find_inferior (&all_threads, unsuspend_one_lwp, except);
2872 static void move_out_of_jump_pad_callback (struct inferior_list_entry *entry);
2873 static int stuck_in_jump_pad_callback (struct inferior_list_entry *entry,
2875 static int lwp_running (struct inferior_list_entry *entry, void *data);
2876 static ptid_t linux_wait_1 (ptid_t ptid,
2877 struct target_waitstatus *ourstatus,
2878 int target_options);
2880 /* Stabilize threads (move out of jump pads).
2882 If a thread is midway collecting a fast tracepoint, we need to
2883 finish the collection and move it out of the jump pad before
2884 reporting the signal.
2886 This avoids recursion while collecting (when a signal arrives
2887 midway, and the signal handler itself collects), which would trash
2888 the trace buffer. In case the user set a breakpoint in a signal
2889 handler, this avoids the backtrace showing the jump pad, etc..
2890 Most importantly, there are certain things we can't do safely if
2891 threads are stopped in a jump pad (or in its callee's). For
2894 - starting a new trace run. A thread still collecting the
2895 previous run, could trash the trace buffer when resumed. The trace
2896 buffer control structures would have been reset but the thread had
2897 no way to tell. The thread could even midway memcpy'ing to the
2898 buffer, which would mean that when resumed, it would clobber the
2899 trace buffer that had been set for a new run.
2901 - we can't rewrite/reuse the jump pads for new tracepoints
2902 safely. Say you do tstart while a thread is stopped midway while
2903 collecting. When the thread is later resumed, it finishes the
2904 collection, and returns to the jump pad, to execute the original
2905 instruction that was under the tracepoint jump at the time the
2906 older run had been started. If the jump pad had been rewritten
2907 since for something else in the new run, the thread would now
2908 execute the wrong / random instructions. */
2911 linux_stabilize_threads (void)
2913 struct thread_info *saved_thread;
2914 struct thread_info *thread_stuck;
2917 = (struct thread_info *) find_inferior (&all_threads,
2918 stuck_in_jump_pad_callback,
2920 if (thread_stuck != NULL)
2923 debug_printf ("can't stabilize, LWP %ld is stuck in jump pad\n",
2924 lwpid_of (thread_stuck));
2928 saved_thread = current_thread;
2930 stabilizing_threads = 1;
2933 for_each_inferior (&all_threads, move_out_of_jump_pad_callback);
2935 /* Loop until all are stopped out of the jump pads. */
2936 while (find_inferior (&all_threads, lwp_running, NULL) != NULL)
2938 struct target_waitstatus ourstatus;
2939 struct lwp_info *lwp;
2942 /* Note that we go through the full wait even loop. While
2943 moving threads out of jump pad, we need to be able to step
2944 over internal breakpoints and such. */
2945 linux_wait_1 (minus_one_ptid, &ourstatus, 0);
2947 if (ourstatus.kind == TARGET_WAITKIND_STOPPED)
2949 lwp = get_thread_lwp (current_thread);
2952 lwp_suspended_inc (lwp);
2954 if (ourstatus.value.sig != GDB_SIGNAL_0
2955 || current_thread->last_resume_kind == resume_stop)
2957 wstat = W_STOPCODE (gdb_signal_to_host (ourstatus.value.sig));
2958 enqueue_one_deferred_signal (lwp, &wstat);
2963 find_inferior (&all_threads, unsuspend_one_lwp, NULL);
2965 stabilizing_threads = 0;
2967 current_thread = saved_thread;
2972 = (struct thread_info *) find_inferior (&all_threads,
2973 stuck_in_jump_pad_callback,
2975 if (thread_stuck != NULL)
2976 debug_printf ("couldn't stabilize, LWP %ld got stuck in jump pad\n",
2977 lwpid_of (thread_stuck));
2981 /* Convenience function that is called when the kernel reports an
2982 event that is not passed out to GDB. */
2985 ignore_event (struct target_waitstatus *ourstatus)
2987 /* If we got an event, there may still be others, as a single
2988 SIGCHLD can indicate more than one child stopped. This forces
2989 another target_wait call. */
2992 ourstatus->kind = TARGET_WAITKIND_IGNORE;
2996 /* Convenience function that is called when the kernel reports an exit
2997 event. This decides whether to report the event to GDB as a
2998 process exit event, a thread exit event, or to suppress the
3002 filter_exit_event (struct lwp_info *event_child,
3003 struct target_waitstatus *ourstatus)
3005 struct thread_info *thread = get_lwp_thread (event_child);
3006 ptid_t ptid = ptid_of (thread);
3008 if (!last_thread_of_process_p (pid_of (thread)))
3010 if (report_thread_events)
3011 ourstatus->kind = TARGET_WAITKIND_THREAD_EXITED;
3013 ourstatus->kind = TARGET_WAITKIND_IGNORE;
3015 delete_lwp (event_child);
3020 /* Returns 1 if GDB is interested in any event_child syscalls. */
3023 gdb_catching_syscalls_p (struct lwp_info *event_child)
3025 struct thread_info *thread = get_lwp_thread (event_child);
3026 struct process_info *proc = get_thread_process (thread);
3028 return !VEC_empty (int, proc->syscalls_to_catch);
3031 /* Returns 1 if GDB is interested in the event_child syscall.
3032 Only to be called when stopped reason is SYSCALL_SIGTRAP. */
3035 gdb_catch_this_syscall_p (struct lwp_info *event_child)
3039 struct thread_info *thread = get_lwp_thread (event_child);
3040 struct process_info *proc = get_thread_process (thread);
3042 if (VEC_empty (int, proc->syscalls_to_catch))
3045 if (VEC_index (int, proc->syscalls_to_catch, 0) == ANY_SYSCALL)
3048 get_syscall_trapinfo (event_child, &sysno, &sysret);
3050 VEC_iterate (int, proc->syscalls_to_catch, i, iter);
3058 /* Wait for process, returns status. */
3061 linux_wait_1 (ptid_t ptid,
3062 struct target_waitstatus *ourstatus, int target_options)
3065 struct lwp_info *event_child;
3068 int step_over_finished;
3069 int bp_explains_trap;
3070 int maybe_internal_trap;
3079 debug_printf ("linux_wait_1: [%s]\n", target_pid_to_str (ptid));
3082 /* Translate generic target options into linux options. */
3084 if (target_options & TARGET_WNOHANG)
3087 bp_explains_trap = 0;
3090 ourstatus->kind = TARGET_WAITKIND_IGNORE;
3092 /* Find a resumed LWP, if any. */
3093 if (find_inferior (&all_threads,
3094 status_pending_p_callback,
3095 &minus_one_ptid) != NULL)
3097 else if ((find_inferior (&all_threads,
3098 not_stopped_callback,
3099 &minus_one_ptid) != NULL))
3104 if (ptid_equal (step_over_bkpt, null_ptid))
3105 pid = linux_wait_for_event (ptid, &w, options);
3109 debug_printf ("step_over_bkpt set [%s], doing a blocking wait\n",
3110 target_pid_to_str (step_over_bkpt));
3111 pid = linux_wait_for_event (step_over_bkpt, &w, options & ~WNOHANG);
3114 if (pid == 0 || (pid == -1 && !any_resumed))
3116 gdb_assert (target_options & TARGET_WNOHANG);
3120 debug_printf ("linux_wait_1 ret = null_ptid, "
3121 "TARGET_WAITKIND_IGNORE\n");
3125 ourstatus->kind = TARGET_WAITKIND_IGNORE;
3132 debug_printf ("linux_wait_1 ret = null_ptid, "
3133 "TARGET_WAITKIND_NO_RESUMED\n");
3137 ourstatus->kind = TARGET_WAITKIND_NO_RESUMED;
3141 event_child = get_thread_lwp (current_thread);
3143 /* linux_wait_for_event only returns an exit status for the last
3144 child of a process. Report it. */
3145 if (WIFEXITED (w) || WIFSIGNALED (w))
3149 ourstatus->kind = TARGET_WAITKIND_EXITED;
3150 ourstatus->value.integer = WEXITSTATUS (w);
3154 debug_printf ("linux_wait_1 ret = %s, exited with "
3156 target_pid_to_str (ptid_of (current_thread)),
3163 ourstatus->kind = TARGET_WAITKIND_SIGNALLED;
3164 ourstatus->value.sig = gdb_signal_from_host (WTERMSIG (w));
3168 debug_printf ("linux_wait_1 ret = %s, terminated with "
3170 target_pid_to_str (ptid_of (current_thread)),
3176 if (ourstatus->kind == TARGET_WAITKIND_EXITED)
3177 return filter_exit_event (event_child, ourstatus);
3179 return ptid_of (current_thread);
3182 /* If step-over executes a breakpoint instruction, in the case of a
3183 hardware single step it means a gdb/gdbserver breakpoint had been
3184 planted on top of a permanent breakpoint, in the case of a software
3185 single step it may just mean that gdbserver hit the reinsert breakpoint.
3186 The PC has been adjusted by save_stop_reason to point at
3187 the breakpoint address.
3188 So in the case of the hardware single step advance the PC manually
3189 past the breakpoint and in the case of software single step advance only
3190 if it's not the reinsert_breakpoint we are hitting.
3191 This avoids that a program would keep trapping a permanent breakpoint
3193 if (!ptid_equal (step_over_bkpt, null_ptid)
3194 && event_child->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT
3195 && (event_child->stepping
3196 || !reinsert_breakpoint_inserted_here (event_child->stop_pc)))
3198 int increment_pc = 0;
3199 int breakpoint_kind = 0;
3200 CORE_ADDR stop_pc = event_child->stop_pc;
3203 the_target->breakpoint_kind_from_current_state (&stop_pc);
3204 the_target->sw_breakpoint_from_kind (breakpoint_kind, &increment_pc);
3208 debug_printf ("step-over for %s executed software breakpoint\n",
3209 target_pid_to_str (ptid_of (current_thread)));
3212 if (increment_pc != 0)
3214 struct regcache *regcache
3215 = get_thread_regcache (current_thread, 1);
3217 event_child->stop_pc += increment_pc;
3218 (*the_low_target.set_pc) (regcache, event_child->stop_pc);
3220 if (!(*the_low_target.breakpoint_at) (event_child->stop_pc))
3221 event_child->stop_reason = TARGET_STOPPED_BY_NO_REASON;
3225 /* If this event was not handled before, and is not a SIGTRAP, we
3226 report it. SIGILL and SIGSEGV are also treated as traps in case
3227 a breakpoint is inserted at the current PC. If this target does
3228 not support internal breakpoints at all, we also report the
3229 SIGTRAP without further processing; it's of no concern to us. */
3231 = (supports_breakpoints ()
3232 && (WSTOPSIG (w) == SIGTRAP
3233 || ((WSTOPSIG (w) == SIGILL
3234 || WSTOPSIG (w) == SIGSEGV)
3235 && (*the_low_target.breakpoint_at) (event_child->stop_pc))));
3237 if (maybe_internal_trap)
3239 /* Handle anything that requires bookkeeping before deciding to
3240 report the event or continue waiting. */
3242 /* First check if we can explain the SIGTRAP with an internal
3243 breakpoint, or if we should possibly report the event to GDB.
3244 Do this before anything that may remove or insert a
3246 bp_explains_trap = breakpoint_inserted_here (event_child->stop_pc);
3248 /* We have a SIGTRAP, possibly a step-over dance has just
3249 finished. If so, tweak the state machine accordingly,
3250 reinsert breakpoints and delete any reinsert (software
3251 single-step) breakpoints. */
3252 step_over_finished = finish_step_over (event_child);
3254 /* Now invoke the callbacks of any internal breakpoints there. */
3255 check_breakpoints (event_child->stop_pc);
3257 /* Handle tracepoint data collecting. This may overflow the
3258 trace buffer, and cause a tracing stop, removing
3260 trace_event = handle_tracepoints (event_child);
3262 if (bp_explains_trap)
3264 /* If we stepped or ran into an internal breakpoint, we've
3265 already handled it. So next time we resume (from this
3266 PC), we should step over it. */
3268 debug_printf ("Hit a gdbserver breakpoint.\n");
3270 if (breakpoint_here (event_child->stop_pc))
3271 event_child->need_step_over = 1;
3276 /* We have some other signal, possibly a step-over dance was in
3277 progress, and it should be cancelled too. */
3278 step_over_finished = finish_step_over (event_child);
3281 /* We have all the data we need. Either report the event to GDB, or
3282 resume threads and keep waiting for more. */
3284 /* If we're collecting a fast tracepoint, finish the collection and
3285 move out of the jump pad before delivering a signal. See
3286 linux_stabilize_threads. */
3289 && WSTOPSIG (w) != SIGTRAP
3290 && supports_fast_tracepoints ()
3291 && agent_loaded_p ())
3294 debug_printf ("Got signal %d for LWP %ld. Check if we need "
3295 "to defer or adjust it.\n",
3296 WSTOPSIG (w), lwpid_of (current_thread));
3298 /* Allow debugging the jump pad itself. */
3299 if (current_thread->last_resume_kind != resume_step
3300 && maybe_move_out_of_jump_pad (event_child, &w))
3302 enqueue_one_deferred_signal (event_child, &w);
3305 debug_printf ("Signal %d for LWP %ld deferred (in jump pad)\n",
3306 WSTOPSIG (w), lwpid_of (current_thread));
3308 linux_resume_one_lwp (event_child, 0, 0, NULL);
3310 return ignore_event (ourstatus);
3314 if (event_child->collecting_fast_tracepoint)
3317 debug_printf ("LWP %ld was trying to move out of the jump pad (%d). "
3318 "Check if we're already there.\n",
3319 lwpid_of (current_thread),
3320 event_child->collecting_fast_tracepoint);
3324 event_child->collecting_fast_tracepoint
3325 = linux_fast_tracepoint_collecting (event_child, NULL);
3327 if (event_child->collecting_fast_tracepoint != 1)
3329 /* No longer need this breakpoint. */
3330 if (event_child->exit_jump_pad_bkpt != NULL)
3333 debug_printf ("No longer need exit-jump-pad bkpt; removing it."
3334 "stopping all threads momentarily.\n");
3336 /* Other running threads could hit this breakpoint.
3337 We don't handle moribund locations like GDB does,
3338 instead we always pause all threads when removing
3339 breakpoints, so that any step-over or
3340 decr_pc_after_break adjustment is always taken
3341 care of while the breakpoint is still
3343 stop_all_lwps (1, event_child);
3345 delete_breakpoint (event_child->exit_jump_pad_bkpt);
3346 event_child->exit_jump_pad_bkpt = NULL;
3348 unstop_all_lwps (1, event_child);
3350 gdb_assert (event_child->suspended >= 0);
3354 if (event_child->collecting_fast_tracepoint == 0)
3357 debug_printf ("fast tracepoint finished "
3358 "collecting successfully.\n");
3360 /* We may have a deferred signal to report. */
3361 if (dequeue_one_deferred_signal (event_child, &w))
3364 debug_printf ("dequeued one signal.\n");
3369 debug_printf ("no deferred signals.\n");
3371 if (stabilizing_threads)
3373 ourstatus->kind = TARGET_WAITKIND_STOPPED;
3374 ourstatus->value.sig = GDB_SIGNAL_0;
3378 debug_printf ("linux_wait_1 ret = %s, stopped "
3379 "while stabilizing threads\n",
3380 target_pid_to_str (ptid_of (current_thread)));
3384 return ptid_of (current_thread);
3390 /* Check whether GDB would be interested in this event. */
3392 /* Check if GDB is interested in this syscall. */
3394 && WSTOPSIG (w) == SYSCALL_SIGTRAP
3395 && !gdb_catch_this_syscall_p (event_child))
3399 debug_printf ("Ignored syscall for LWP %ld.\n",
3400 lwpid_of (current_thread));
3403 linux_resume_one_lwp (event_child, event_child->stepping,
3405 return ignore_event (ourstatus);
3408 /* If GDB is not interested in this signal, don't stop other
3409 threads, and don't report it to GDB. Just resume the inferior
3410 right away. We do this for threading-related signals as well as
3411 any that GDB specifically requested we ignore. But never ignore
3412 SIGSTOP if we sent it ourselves, and do not ignore signals when
3413 stepping - they may require special handling to skip the signal
3414 handler. Also never ignore signals that could be caused by a
3417 && current_thread->last_resume_kind != resume_step
3419 #if defined (USE_THREAD_DB) && !defined (__ANDROID__)
3420 (current_process ()->priv->thread_db != NULL
3421 && (WSTOPSIG (w) == __SIGRTMIN
3422 || WSTOPSIG (w) == __SIGRTMIN + 1))
3425 (pass_signals[gdb_signal_from_host (WSTOPSIG (w))]
3426 && !(WSTOPSIG (w) == SIGSTOP
3427 && current_thread->last_resume_kind == resume_stop)
3428 && !linux_wstatus_maybe_breakpoint (w))))
3430 siginfo_t info, *info_p;
3433 debug_printf ("Ignored signal %d for LWP %ld.\n",
3434 WSTOPSIG (w), lwpid_of (current_thread));
3436 if (ptrace (PTRACE_GETSIGINFO, lwpid_of (current_thread),
3437 (PTRACE_TYPE_ARG3) 0, &info) == 0)
3442 if (step_over_finished)
3444 /* We cancelled this thread's step-over above. We still
3445 need to unsuspend all other LWPs, and set them back
3446 running again while the signal handler runs. */
3447 unsuspend_all_lwps (event_child);
3449 /* Enqueue the pending signal info so that proceed_all_lwps
3451 enqueue_pending_signal (event_child, WSTOPSIG (w), info_p);
3453 proceed_all_lwps ();
3457 linux_resume_one_lwp (event_child, event_child->stepping,
3458 WSTOPSIG (w), info_p);
3460 return ignore_event (ourstatus);
3463 /* Note that all addresses are always "out of the step range" when
3464 there's no range to begin with. */
3465 in_step_range = lwp_in_step_range (event_child);
3467 /* If GDB wanted this thread to single step, and the thread is out
3468 of the step range, we always want to report the SIGTRAP, and let
3469 GDB handle it. Watchpoints should always be reported. So should
3470 signals we can't explain. A SIGTRAP we can't explain could be a
3471 GDB breakpoint --- we may or not support Z0 breakpoints. If we
3472 do, we're be able to handle GDB breakpoints on top of internal
3473 breakpoints, by handling the internal breakpoint and still
3474 reporting the event to GDB. If we don't, we're out of luck, GDB
3475 won't see the breakpoint hit. If we see a single-step event but
3476 the thread should be continuing, don't pass the trap to gdb.
3477 That indicates that we had previously finished a single-step but
3478 left the single-step pending -- see
3479 complete_ongoing_step_over. */
3480 report_to_gdb = (!maybe_internal_trap
3481 || (current_thread->last_resume_kind == resume_step
3483 || event_child->stop_reason == TARGET_STOPPED_BY_WATCHPOINT
3485 && !bp_explains_trap
3487 && !step_over_finished
3488 && !(current_thread->last_resume_kind == resume_continue
3489 && event_child->stop_reason == TARGET_STOPPED_BY_SINGLE_STEP))
3490 || (gdb_breakpoint_here (event_child->stop_pc)
3491 && gdb_condition_true_at_breakpoint (event_child->stop_pc)
3492 && gdb_no_commands_at_breakpoint (event_child->stop_pc))
3493 || event_child->waitstatus.kind != TARGET_WAITKIND_IGNORE);
3495 run_breakpoint_commands (event_child->stop_pc);
3497 /* We found no reason GDB would want us to stop. We either hit one
3498 of our own breakpoints, or finished an internal step GDB
3499 shouldn't know about. */
3504 if (bp_explains_trap)
3505 debug_printf ("Hit a gdbserver breakpoint.\n");
3506 if (step_over_finished)
3507 debug_printf ("Step-over finished.\n");
3509 debug_printf ("Tracepoint event.\n");
3510 if (lwp_in_step_range (event_child))
3511 debug_printf ("Range stepping pc 0x%s [0x%s, 0x%s).\n",
3512 paddress (event_child->stop_pc),
3513 paddress (event_child->step_range_start),
3514 paddress (event_child->step_range_end));
3517 /* We're not reporting this breakpoint to GDB, so apply the
3518 decr_pc_after_break adjustment to the inferior's regcache
3521 if (the_low_target.set_pc != NULL)
3523 struct regcache *regcache
3524 = get_thread_regcache (current_thread, 1);
3525 (*the_low_target.set_pc) (regcache, event_child->stop_pc);
3528 /* We may have finished stepping over a breakpoint. If so,
3529 we've stopped and suspended all LWPs momentarily except the
3530 stepping one. This is where we resume them all again. We're
3531 going to keep waiting, so use proceed, which handles stepping
3532 over the next breakpoint. */
3534 debug_printf ("proceeding all threads.\n");
3536 if (step_over_finished)
3537 unsuspend_all_lwps (event_child);
3539 proceed_all_lwps ();
3540 return ignore_event (ourstatus);
3545 if (event_child->waitstatus.kind != TARGET_WAITKIND_IGNORE)
3549 str = target_waitstatus_to_string (&event_child->waitstatus);
3550 debug_printf ("LWP %ld: extended event with waitstatus %s\n",
3551 lwpid_of (get_lwp_thread (event_child)), str);
3554 if (current_thread->last_resume_kind == resume_step)
3556 if (event_child->step_range_start == event_child->step_range_end)
3557 debug_printf ("GDB wanted to single-step, reporting event.\n");
3558 else if (!lwp_in_step_range (event_child))
3559 debug_printf ("Out of step range, reporting event.\n");
3561 if (event_child->stop_reason == TARGET_STOPPED_BY_WATCHPOINT)
3562 debug_printf ("Stopped by watchpoint.\n");
3563 else if (gdb_breakpoint_here (event_child->stop_pc))
3564 debug_printf ("Stopped by GDB breakpoint.\n");
3566 debug_printf ("Hit a non-gdbserver trap event.\n");
3569 /* Alright, we're going to report a stop. */
3571 if (!stabilizing_threads)
3573 /* In all-stop, stop all threads. */
3575 stop_all_lwps (0, NULL);
3577 /* If we're not waiting for a specific LWP, choose an event LWP
3578 from among those that have had events. Giving equal priority
3579 to all LWPs that have had events helps prevent
3581 if (ptid_equal (ptid, minus_one_ptid))
3583 event_child->status_pending_p = 1;
3584 event_child->status_pending = w;
3586 select_event_lwp (&event_child);
3588 /* current_thread and event_child must stay in sync. */
3589 current_thread = get_lwp_thread (event_child);
3591 event_child->status_pending_p = 0;
3592 w = event_child->status_pending;
3595 if (step_over_finished)
3599 /* If we were doing a step-over, all other threads but
3600 the stepping one had been paused in start_step_over,
3601 with their suspend counts incremented. We don't want
3602 to do a full unstop/unpause, because we're in
3603 all-stop mode (so we want threads stopped), but we
3604 still need to unsuspend the other threads, to
3605 decrement their `suspended' count back. */
3606 unsuspend_all_lwps (event_child);
3610 /* If we just finished a step-over, then all threads had
3611 been momentarily paused. In all-stop, that's fine,
3612 we want threads stopped by now anyway. In non-stop,
3613 we need to re-resume threads that GDB wanted to be
3615 unstop_all_lwps (1, event_child);
3619 /* Stabilize threads (move out of jump pads). */
3621 stabilize_threads ();
3625 /* If we just finished a step-over, then all threads had been
3626 momentarily paused. In all-stop, that's fine, we want
3627 threads stopped by now anyway. In non-stop, we need to
3628 re-resume threads that GDB wanted to be running. */
3629 if (step_over_finished)
3630 unstop_all_lwps (1, event_child);
3633 if (event_child->waitstatus.kind != TARGET_WAITKIND_IGNORE)
3635 /* If the reported event is an exit, fork, vfork or exec, let
3637 *ourstatus = event_child->waitstatus;
3638 /* Clear the event lwp's waitstatus since we handled it already. */
3639 event_child->waitstatus.kind = TARGET_WAITKIND_IGNORE;
3642 ourstatus->kind = TARGET_WAITKIND_STOPPED;
3644 /* Now that we've selected our final event LWP, un-adjust its PC if
3645 it was a software breakpoint, and the client doesn't know we can
3646 adjust the breakpoint ourselves. */
3647 if (event_child->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT
3648 && !swbreak_feature)
3650 int decr_pc = the_low_target.decr_pc_after_break;
3654 struct regcache *regcache
3655 = get_thread_regcache (current_thread, 1);
3656 (*the_low_target.set_pc) (regcache, event_child->stop_pc + decr_pc);
3660 if (WSTOPSIG (w) == SYSCALL_SIGTRAP)
3664 get_syscall_trapinfo (event_child,
3665 &ourstatus->value.syscall_number, &sysret);
3666 ourstatus->kind = event_child->syscall_state;
3668 else if (current_thread->last_resume_kind == resume_stop
3669 && WSTOPSIG (w) == SIGSTOP)
3671 /* A thread that has been requested to stop by GDB with vCont;t,
3672 and it stopped cleanly, so report as SIG0. The use of
3673 SIGSTOP is an implementation detail. */
3674 ourstatus->value.sig = GDB_SIGNAL_0;
3676 else if (current_thread->last_resume_kind == resume_stop
3677 && WSTOPSIG (w) != SIGSTOP)
3679 /* A thread that has been requested to stop by GDB with vCont;t,
3680 but, it stopped for other reasons. */
3681 ourstatus->value.sig = gdb_signal_from_host (WSTOPSIG (w));
3683 else if (ourstatus->kind == TARGET_WAITKIND_STOPPED)
3685 ourstatus->value.sig = gdb_signal_from_host (WSTOPSIG (w));
3688 gdb_assert (ptid_equal (step_over_bkpt, null_ptid));
3692 debug_printf ("linux_wait_1 ret = %s, %d, %d\n",
3693 target_pid_to_str (ptid_of (current_thread)),
3694 ourstatus->kind, ourstatus->value.sig);
3698 if (ourstatus->kind == TARGET_WAITKIND_EXITED)
3699 return filter_exit_event (event_child, ourstatus);
3701 return ptid_of (current_thread);
3704 /* Get rid of any pending event in the pipe. */
3706 async_file_flush (void)
3712 ret = read (linux_event_pipe[0], &buf, 1);
3713 while (ret >= 0 || (ret == -1 && errno == EINTR));
3716 /* Put something in the pipe, so the event loop wakes up. */
3718 async_file_mark (void)
3722 async_file_flush ();
3725 ret = write (linux_event_pipe[1], "+", 1);
3726 while (ret == 0 || (ret == -1 && errno == EINTR));
3728 /* Ignore EAGAIN. If the pipe is full, the event loop will already
3729 be awakened anyway. */
3733 linux_wait (ptid_t ptid,
3734 struct target_waitstatus *ourstatus, int target_options)
3738 /* Flush the async file first. */
3739 if (target_is_async_p ())
3740 async_file_flush ();
3744 event_ptid = linux_wait_1 (ptid, ourstatus, target_options);
3746 while ((target_options & TARGET_WNOHANG) == 0
3747 && ptid_equal (event_ptid, null_ptid)
3748 && ourstatus->kind == TARGET_WAITKIND_IGNORE);
3750 /* If at least one stop was reported, there may be more. A single
3751 SIGCHLD can signal more than one child stop. */
3752 if (target_is_async_p ()
3753 && (target_options & TARGET_WNOHANG) != 0
3754 && !ptid_equal (event_ptid, null_ptid))
3760 /* Send a signal to an LWP. */
3763 kill_lwp (unsigned long lwpid, int signo)
3768 ret = syscall (__NR_tkill, lwpid, signo);
3769 if (errno == ENOSYS)
3771 /* If tkill fails, then we are not using nptl threads, a
3772 configuration we no longer support. */
3773 perror_with_name (("tkill"));
3779 linux_stop_lwp (struct lwp_info *lwp)
3785 send_sigstop (struct lwp_info *lwp)
3789 pid = lwpid_of (get_lwp_thread (lwp));
3791 /* If we already have a pending stop signal for this process, don't
3793 if (lwp->stop_expected)
3796 debug_printf ("Have pending sigstop for lwp %d\n", pid);
3802 debug_printf ("Sending sigstop to lwp %d\n", pid);
3804 lwp->stop_expected = 1;
3805 kill_lwp (pid, SIGSTOP);
3809 send_sigstop_callback (struct inferior_list_entry *entry, void *except)
3811 struct thread_info *thread = (struct thread_info *) entry;
3812 struct lwp_info *lwp = get_thread_lwp (thread);
3814 /* Ignore EXCEPT. */
3825 /* Increment the suspend count of an LWP, and stop it, if not stopped
3828 suspend_and_send_sigstop_callback (struct inferior_list_entry *entry,
3831 struct thread_info *thread = (struct thread_info *) entry;
3832 struct lwp_info *lwp = get_thread_lwp (thread);
3834 /* Ignore EXCEPT. */
3838 lwp_suspended_inc (lwp);
3840 return send_sigstop_callback (entry, except);
3844 mark_lwp_dead (struct lwp_info *lwp, int wstat)
3846 /* Store the exit status for later. */
3847 lwp->status_pending_p = 1;
3848 lwp->status_pending = wstat;
3850 /* Store in waitstatus as well, as there's nothing else to process
3852 if (WIFEXITED (wstat))
3854 lwp->waitstatus.kind = TARGET_WAITKIND_EXITED;
3855 lwp->waitstatus.value.integer = WEXITSTATUS (wstat);
3857 else if (WIFSIGNALED (wstat))
3859 lwp->waitstatus.kind = TARGET_WAITKIND_SIGNALLED;
3860 lwp->waitstatus.value.sig = gdb_signal_from_host (WTERMSIG (wstat));
3863 /* Prevent trying to stop it. */
3866 /* No further stops are expected from a dead lwp. */
3867 lwp->stop_expected = 0;
3870 /* Return true if LWP has exited already, and has a pending exit event
3871 to report to GDB. */
3874 lwp_is_marked_dead (struct lwp_info *lwp)
3876 return (lwp->status_pending_p
3877 && (WIFEXITED (lwp->status_pending)
3878 || WIFSIGNALED (lwp->status_pending)));
3881 /* Wait for all children to stop for the SIGSTOPs we just queued. */
3884 wait_for_sigstop (void)
3886 struct thread_info *saved_thread;
3891 saved_thread = current_thread;
3892 if (saved_thread != NULL)
3893 saved_tid = saved_thread->entry.id;
3895 saved_tid = null_ptid; /* avoid bogus unused warning */
3898 debug_printf ("wait_for_sigstop: pulling events\n");
3900 /* Passing NULL_PTID as filter indicates we want all events to be
3901 left pending. Eventually this returns when there are no
3902 unwaited-for children left. */
3903 ret = linux_wait_for_event_filtered (minus_one_ptid, null_ptid,
3905 gdb_assert (ret == -1);
3907 if (saved_thread == NULL || linux_thread_alive (saved_tid))
3908 current_thread = saved_thread;
3912 debug_printf ("Previously current thread died.\n");
3914 /* We can't change the current inferior behind GDB's back,
3915 otherwise, a subsequent command may apply to the wrong
3917 current_thread = NULL;
3921 /* Returns true if LWP ENTRY is stopped in a jump pad, and we can't
3922 move it out, because we need to report the stop event to GDB. For
3923 example, if the user puts a breakpoint in the jump pad, it's
3924 because she wants to debug it. */
3927 stuck_in_jump_pad_callback (struct inferior_list_entry *entry, void *data)
3929 struct thread_info *thread = (struct thread_info *) entry;
3930 struct lwp_info *lwp = get_thread_lwp (thread);
3932 if (lwp->suspended != 0)
3934 internal_error (__FILE__, __LINE__,
3935 "LWP %ld is suspended, suspended=%d\n",
3936 lwpid_of (thread), lwp->suspended);
3938 gdb_assert (lwp->stopped);
3940 /* Allow debugging the jump pad, gdb_collect, etc.. */
3941 return (supports_fast_tracepoints ()
3942 && agent_loaded_p ()
3943 && (gdb_breakpoint_here (lwp->stop_pc)
3944 || lwp->stop_reason == TARGET_STOPPED_BY_WATCHPOINT
3945 || thread->last_resume_kind == resume_step)
3946 && linux_fast_tracepoint_collecting (lwp, NULL));
3950 move_out_of_jump_pad_callback (struct inferior_list_entry *entry)
3952 struct thread_info *thread = (struct thread_info *) entry;
3953 struct thread_info *saved_thread;
3954 struct lwp_info *lwp = get_thread_lwp (thread);
3957 if (lwp->suspended != 0)
3959 internal_error (__FILE__, __LINE__,
3960 "LWP %ld is suspended, suspended=%d\n",
3961 lwpid_of (thread), lwp->suspended);
3963 gdb_assert (lwp->stopped);
3965 /* For gdb_breakpoint_here. */
3966 saved_thread = current_thread;
3967 current_thread = thread;
3969 wstat = lwp->status_pending_p ? &lwp->status_pending : NULL;
3971 /* Allow debugging the jump pad, gdb_collect, etc. */
3972 if (!gdb_breakpoint_here (lwp->stop_pc)
3973 && lwp->stop_reason != TARGET_STOPPED_BY_WATCHPOINT
3974 && thread->last_resume_kind != resume_step
3975 && maybe_move_out_of_jump_pad (lwp, wstat))
3978 debug_printf ("LWP %ld needs stabilizing (in jump pad)\n",
3983 lwp->status_pending_p = 0;
3984 enqueue_one_deferred_signal (lwp, wstat);
3987 debug_printf ("Signal %d for LWP %ld deferred "
3989 WSTOPSIG (*wstat), lwpid_of (thread));
3992 linux_resume_one_lwp (lwp, 0, 0, NULL);
3995 lwp_suspended_inc (lwp);
3997 current_thread = saved_thread;
4001 lwp_running (struct inferior_list_entry *entry, void *data)
4003 struct thread_info *thread = (struct thread_info *) entry;
4004 struct lwp_info *lwp = get_thread_lwp (thread);
4006 if (lwp_is_marked_dead (lwp))
4013 /* Stop all lwps that aren't stopped yet, except EXCEPT, if not NULL.
4014 If SUSPEND, then also increase the suspend count of every LWP,
4018 stop_all_lwps (int suspend, struct lwp_info *except)
4020 /* Should not be called recursively. */
4021 gdb_assert (stopping_threads == NOT_STOPPING_THREADS);
4026 debug_printf ("stop_all_lwps (%s, except=%s)\n",
4027 suspend ? "stop-and-suspend" : "stop",
4029 ? target_pid_to_str (ptid_of (get_lwp_thread (except)))
4033 stopping_threads = (suspend
4034 ? STOPPING_AND_SUSPENDING_THREADS
4035 : STOPPING_THREADS);
4038 find_inferior (&all_threads, suspend_and_send_sigstop_callback, except);
4040 find_inferior (&all_threads, send_sigstop_callback, except);
4041 wait_for_sigstop ();
4042 stopping_threads = NOT_STOPPING_THREADS;
4046 debug_printf ("stop_all_lwps done, setting stopping_threads "
4047 "back to !stopping\n");
4052 /* Enqueue one signal in the chain of signals which need to be
4053 delivered to this process on next resume. */
4056 enqueue_pending_signal (struct lwp_info *lwp, int signal, siginfo_t *info)
4058 struct pending_signals *p_sig = XNEW (struct pending_signals);
4060 p_sig->prev = lwp->pending_signals;
4061 p_sig->signal = signal;
4063 memset (&p_sig->info, 0, sizeof (siginfo_t));
4065 memcpy (&p_sig->info, info, sizeof (siginfo_t));
4066 lwp->pending_signals = p_sig;
4069 /* Install breakpoints for software single stepping. */
4072 install_software_single_step_breakpoints (struct lwp_info *lwp)
4076 struct regcache *regcache = get_thread_regcache (current_thread, 1);
4077 VEC (CORE_ADDR) *next_pcs = NULL;
4078 struct cleanup *old_chain = make_cleanup (VEC_cleanup (CORE_ADDR), &next_pcs);
4080 next_pcs = (*the_low_target.get_next_pcs) (regcache);
4082 for (i = 0; VEC_iterate (CORE_ADDR, next_pcs, i, pc); ++i)
4083 set_reinsert_breakpoint (pc);
4085 do_cleanups (old_chain);
4088 /* Single step via hardware or software single step.
4089 Return 1 if hardware single stepping, 0 if software single stepping
4090 or can't single step. */
4093 single_step (struct lwp_info* lwp)
4097 if (can_hardware_single_step ())
4101 else if (can_software_single_step ())
4103 install_software_single_step_breakpoints (lwp);
4109 debug_printf ("stepping is not implemented on this target");
4115 /* Resume execution of LWP. If STEP is nonzero, single-step it. If
4116 SIGNAL is nonzero, give it that signal. */
4119 linux_resume_one_lwp_throw (struct lwp_info *lwp,
4120 int step, int signal, siginfo_t *info)
4122 struct thread_info *thread = get_lwp_thread (lwp);
4123 struct thread_info *saved_thread;
4124 int fast_tp_collecting;
4126 struct process_info *proc = get_thread_process (thread);
4128 /* Note that target description may not be initialised
4129 (proc->tdesc == NULL) at this point because the program hasn't
4130 stopped at the first instruction yet. It means GDBserver skips
4131 the extra traps from the wrapper program (see option --wrapper).
4132 Code in this function that requires register access should be
4133 guarded by proc->tdesc == NULL or something else. */
4135 if (lwp->stopped == 0)
4138 gdb_assert (lwp->waitstatus.kind == TARGET_WAITKIND_IGNORE);
4140 fast_tp_collecting = lwp->collecting_fast_tracepoint;
4142 gdb_assert (!stabilizing_threads || fast_tp_collecting);
4144 /* Cancel actions that rely on GDB not changing the PC (e.g., the
4145 user used the "jump" command, or "set $pc = foo"). */
4146 if (thread->while_stepping != NULL && lwp->stop_pc != get_pc (lwp))
4148 /* Collecting 'while-stepping' actions doesn't make sense
4150 release_while_stepping_state_list (thread);
4153 /* If we have pending signals or status, and a new signal, enqueue the
4154 signal. Also enqueue the signal if we are waiting to reinsert a
4155 breakpoint; it will be picked up again below. */
4157 && (lwp->status_pending_p
4158 || lwp->pending_signals != NULL
4159 || lwp->bp_reinsert != 0
4160 || fast_tp_collecting))
4161 enqueue_pending_signal (lwp, signal, info);
4163 if (lwp->status_pending_p)
4166 debug_printf ("Not resuming lwp %ld (%s, signal %d, stop %s);"
4167 " has pending status\n",
4168 lwpid_of (thread), step ? "step" : "continue", signal,
4169 lwp->stop_expected ? "expected" : "not expected");
4173 saved_thread = current_thread;
4174 current_thread = thread;
4177 debug_printf ("Resuming lwp %ld (%s, signal %d, stop %s)\n",
4178 lwpid_of (thread), step ? "step" : "continue", signal,
4179 lwp->stop_expected ? "expected" : "not expected");
4181 /* This bit needs some thinking about. If we get a signal that
4182 we must report while a single-step reinsert is still pending,
4183 we often end up resuming the thread. It might be better to
4184 (ew) allow a stack of pending events; then we could be sure that
4185 the reinsert happened right away and not lose any signals.
4187 Making this stack would also shrink the window in which breakpoints are
4188 uninserted (see comment in linux_wait_for_lwp) but not enough for
4189 complete correctness, so it won't solve that problem. It may be
4190 worthwhile just to solve this one, however. */
4191 if (lwp->bp_reinsert != 0)
4194 debug_printf (" pending reinsert at 0x%s\n",
4195 paddress (lwp->bp_reinsert));
4197 if (can_hardware_single_step ())
4199 if (fast_tp_collecting == 0)
4202 fprintf (stderr, "BAD - reinserting but not stepping.\n");
4204 fprintf (stderr, "BAD - reinserting and suspended(%d).\n",
4211 /* Postpone any pending signal. It was enqueued above. */
4215 if (fast_tp_collecting == 1)
4218 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
4219 " (exit-jump-pad-bkpt)\n",
4222 /* Postpone any pending signal. It was enqueued above. */
4225 else if (fast_tp_collecting == 2)
4228 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
4229 " single-stepping\n",
4232 if (can_hardware_single_step ())
4236 internal_error (__FILE__, __LINE__,
4237 "moving out of jump pad single-stepping"
4238 " not implemented on this target");
4241 /* Postpone any pending signal. It was enqueued above. */
4245 /* If we have while-stepping actions in this thread set it stepping.
4246 If we have a signal to deliver, it may or may not be set to
4247 SIG_IGN, we don't know. Assume so, and allow collecting
4248 while-stepping into a signal handler. A possible smart thing to
4249 do would be to set an internal breakpoint at the signal return
4250 address, continue, and carry on catching this while-stepping
4251 action only when that breakpoint is hit. A future
4253 if (thread->while_stepping != NULL)
4256 debug_printf ("lwp %ld has a while-stepping action -> forcing step.\n",
4259 step = single_step (lwp);
4262 if (proc->tdesc != NULL && the_low_target.get_pc != NULL)
4264 struct regcache *regcache = get_thread_regcache (current_thread, 1);
4266 lwp->stop_pc = (*the_low_target.get_pc) (regcache);
4270 debug_printf (" %s from pc 0x%lx\n", step ? "step" : "continue",
4271 (long) lwp->stop_pc);
4275 /* If we have pending signals, consume one unless we are trying to
4276 reinsert a breakpoint or we're trying to finish a fast tracepoint
4278 if (lwp->pending_signals != NULL
4279 && lwp->bp_reinsert == 0
4280 && fast_tp_collecting == 0)
4282 struct pending_signals **p_sig;
4284 p_sig = &lwp->pending_signals;
4285 while ((*p_sig)->prev != NULL)
4286 p_sig = &(*p_sig)->prev;
4288 signal = (*p_sig)->signal;
4289 if ((*p_sig)->info.si_signo != 0)
4290 ptrace (PTRACE_SETSIGINFO, lwpid_of (thread), (PTRACE_TYPE_ARG3) 0,
4297 if (the_low_target.prepare_to_resume != NULL)
4298 the_low_target.prepare_to_resume (lwp);
4300 regcache_invalidate_thread (thread);
4302 lwp->stepping = step;
4304 ptrace_request = PTRACE_SINGLESTEP;
4305 else if (gdb_catching_syscalls_p (lwp))
4306 ptrace_request = PTRACE_SYSCALL;
4308 ptrace_request = PTRACE_CONT;
4309 ptrace (ptrace_request,
4311 (PTRACE_TYPE_ARG3) 0,
4312 /* Coerce to a uintptr_t first to avoid potential gcc warning
4313 of coercing an 8 byte integer to a 4 byte pointer. */
4314 (PTRACE_TYPE_ARG4) (uintptr_t) signal);
4316 current_thread = saved_thread;
4318 perror_with_name ("resuming thread");
4320 /* Successfully resumed. Clear state that no longer makes sense,
4321 and mark the LWP as running. Must not do this before resuming
4322 otherwise if that fails other code will be confused. E.g., we'd
4323 later try to stop the LWP and hang forever waiting for a stop
4324 status. Note that we must not throw after this is cleared,
4325 otherwise handle_zombie_lwp_error would get confused. */
4327 lwp->stop_reason = TARGET_STOPPED_BY_NO_REASON;
4330 /* Called when we try to resume a stopped LWP and that errors out. If
4331 the LWP is no longer in ptrace-stopped state (meaning it's zombie,
4332 or about to become), discard the error, clear any pending status
4333 the LWP may have, and return true (we'll collect the exit status
4334 soon enough). Otherwise, return false. */
4337 check_ptrace_stopped_lwp_gone (struct lwp_info *lp)
4339 struct thread_info *thread = get_lwp_thread (lp);
4341 /* If we get an error after resuming the LWP successfully, we'd
4342 confuse !T state for the LWP being gone. */
4343 gdb_assert (lp->stopped);
4345 /* We can't just check whether the LWP is in 'Z (Zombie)' state,
4346 because even if ptrace failed with ESRCH, the tracee may be "not
4347 yet fully dead", but already refusing ptrace requests. In that
4348 case the tracee has 'R (Running)' state for a little bit
4349 (observed in Linux 3.18). See also the note on ESRCH in the
4350 ptrace(2) man page. Instead, check whether the LWP has any state
4351 other than ptrace-stopped. */
4353 /* Don't assume anything if /proc/PID/status can't be read. */
4354 if (linux_proc_pid_is_trace_stopped_nowarn (lwpid_of (thread)) == 0)
4356 lp->stop_reason = TARGET_STOPPED_BY_NO_REASON;
4357 lp->status_pending_p = 0;
4363 /* Like linux_resume_one_lwp_throw, but no error is thrown if the LWP
4364 disappears while we try to resume it. */
4367 linux_resume_one_lwp (struct lwp_info *lwp,
4368 int step, int signal, siginfo_t *info)
4372 linux_resume_one_lwp_throw (lwp, step, signal, info);
4374 CATCH (ex, RETURN_MASK_ERROR)
4376 if (!check_ptrace_stopped_lwp_gone (lwp))
4377 throw_exception (ex);
4382 struct thread_resume_array
4384 struct thread_resume *resume;
4388 /* This function is called once per thread via find_inferior.
4389 ARG is a pointer to a thread_resume_array struct.
4390 We look up the thread specified by ENTRY in ARG, and mark the thread
4391 with a pointer to the appropriate resume request.
4393 This algorithm is O(threads * resume elements), but resume elements
4394 is small (and will remain small at least until GDB supports thread
4398 linux_set_resume_request (struct inferior_list_entry *entry, void *arg)
4400 struct thread_info *thread = (struct thread_info *) entry;
4401 struct lwp_info *lwp = get_thread_lwp (thread);
4403 struct thread_resume_array *r;
4405 r = (struct thread_resume_array *) arg;
4407 for (ndx = 0; ndx < r->n; ndx++)
4409 ptid_t ptid = r->resume[ndx].thread;
4410 if (ptid_equal (ptid, minus_one_ptid)
4411 || ptid_equal (ptid, entry->id)
4412 /* Handle both 'pPID' and 'pPID.-1' as meaning 'all threads
4414 || (ptid_get_pid (ptid) == pid_of (thread)
4415 && (ptid_is_pid (ptid)
4416 || ptid_get_lwp (ptid) == -1)))
4418 if (r->resume[ndx].kind == resume_stop
4419 && thread->last_resume_kind == resume_stop)
4422 debug_printf ("already %s LWP %ld at GDB's request\n",
4423 (thread->last_status.kind
4424 == TARGET_WAITKIND_STOPPED)
4432 lwp->resume = &r->resume[ndx];
4433 thread->last_resume_kind = lwp->resume->kind;
4435 lwp->step_range_start = lwp->resume->step_range_start;
4436 lwp->step_range_end = lwp->resume->step_range_end;
4438 /* If we had a deferred signal to report, dequeue one now.
4439 This can happen if LWP gets more than one signal while
4440 trying to get out of a jump pad. */
4442 && !lwp->status_pending_p
4443 && dequeue_one_deferred_signal (lwp, &lwp->status_pending))
4445 lwp->status_pending_p = 1;
4448 debug_printf ("Dequeueing deferred signal %d for LWP %ld, "
4449 "leaving status pending.\n",
4450 WSTOPSIG (lwp->status_pending),
4458 /* No resume action for this thread. */
4464 /* find_inferior callback for linux_resume.
4465 Set *FLAG_P if this lwp has an interesting status pending. */
4468 resume_status_pending_p (struct inferior_list_entry *entry, void *flag_p)
4470 struct thread_info *thread = (struct thread_info *) entry;
4471 struct lwp_info *lwp = get_thread_lwp (thread);
4473 /* LWPs which will not be resumed are not interesting, because
4474 we might not wait for them next time through linux_wait. */
4475 if (lwp->resume == NULL)
4478 if (thread_still_has_status_pending_p (thread))
4479 * (int *) flag_p = 1;
4484 /* Return 1 if this lwp that GDB wants running is stopped at an
4485 internal breakpoint that we need to step over. It assumes that any
4486 required STOP_PC adjustment has already been propagated to the
4487 inferior's regcache. */
4490 need_step_over_p (struct inferior_list_entry *entry, void *dummy)
4492 struct thread_info *thread = (struct thread_info *) entry;
4493 struct lwp_info *lwp = get_thread_lwp (thread);
4494 struct thread_info *saved_thread;
4496 struct process_info *proc = get_thread_process (thread);
4498 /* GDBserver is skipping the extra traps from the wrapper program,
4499 don't have to do step over. */
4500 if (proc->tdesc == NULL)
4503 /* LWPs which will not be resumed are not interesting, because we
4504 might not wait for them next time through linux_wait. */
4509 debug_printf ("Need step over [LWP %ld]? Ignoring, not stopped\n",
4514 if (thread->last_resume_kind == resume_stop)
4517 debug_printf ("Need step over [LWP %ld]? Ignoring, should remain"
4523 gdb_assert (lwp->suspended >= 0);
4528 debug_printf ("Need step over [LWP %ld]? Ignoring, suspended\n",
4533 if (!lwp->need_step_over)
4536 debug_printf ("Need step over [LWP %ld]? No\n", lwpid_of (thread));
4539 if (lwp->status_pending_p)
4542 debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
4548 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
4552 /* If the PC has changed since we stopped, then don't do anything,
4553 and let the breakpoint/tracepoint be hit. This happens if, for
4554 instance, GDB handled the decr_pc_after_break subtraction itself,
4555 GDB is OOL stepping this thread, or the user has issued a "jump"
4556 command, or poked thread's registers herself. */
4557 if (pc != lwp->stop_pc)
4560 debug_printf ("Need step over [LWP %ld]? Cancelling, PC was changed. "
4561 "Old stop_pc was 0x%s, PC is now 0x%s\n",
4563 paddress (lwp->stop_pc), paddress (pc));
4565 lwp->need_step_over = 0;
4569 saved_thread = current_thread;
4570 current_thread = thread;
4572 /* We can only step over breakpoints we know about. */
4573 if (breakpoint_here (pc) || fast_tracepoint_jump_here (pc))
4575 /* Don't step over a breakpoint that GDB expects to hit
4576 though. If the condition is being evaluated on the target's side
4577 and it evaluate to false, step over this breakpoint as well. */
4578 if (gdb_breakpoint_here (pc)
4579 && gdb_condition_true_at_breakpoint (pc)
4580 && gdb_no_commands_at_breakpoint (pc))
4583 debug_printf ("Need step over [LWP %ld]? yes, but found"
4584 " GDB breakpoint at 0x%s; skipping step over\n",
4585 lwpid_of (thread), paddress (pc));
4587 current_thread = saved_thread;
4593 debug_printf ("Need step over [LWP %ld]? yes, "
4594 "found breakpoint at 0x%s\n",
4595 lwpid_of (thread), paddress (pc));
4597 /* We've found an lwp that needs stepping over --- return 1 so
4598 that find_inferior stops looking. */
4599 current_thread = saved_thread;
4601 /* If the step over is cancelled, this is set again. */
4602 lwp->need_step_over = 0;
4607 current_thread = saved_thread;
4610 debug_printf ("Need step over [LWP %ld]? No, no breakpoint found"
4612 lwpid_of (thread), paddress (pc));
4617 /* Start a step-over operation on LWP. When LWP stopped at a
4618 breakpoint, to make progress, we need to remove the breakpoint out
4619 of the way. If we let other threads run while we do that, they may
4620 pass by the breakpoint location and miss hitting it. To avoid
4621 that, a step-over momentarily stops all threads while LWP is
4622 single-stepped while the breakpoint is temporarily uninserted from
4623 the inferior. When the single-step finishes, we reinsert the
4624 breakpoint, and let all threads that are supposed to be running,
4627 On targets that don't support hardware single-step, we don't
4628 currently support full software single-stepping. Instead, we only
4629 support stepping over the thread event breakpoint, by asking the
4630 low target where to place a reinsert breakpoint. Since this
4631 routine assumes the breakpoint being stepped over is a thread event
4632 breakpoint, it usually assumes the return address of the current
4633 function is a good enough place to set the reinsert breakpoint. */
4636 start_step_over (struct lwp_info *lwp)
4638 struct thread_info *thread = get_lwp_thread (lwp);
4639 struct thread_info *saved_thread;
4644 debug_printf ("Starting step-over on LWP %ld. Stopping all threads\n",
4647 stop_all_lwps (1, lwp);
4649 if (lwp->suspended != 0)
4651 internal_error (__FILE__, __LINE__,
4652 "LWP %ld suspended=%d\n", lwpid_of (thread),
4657 debug_printf ("Done stopping all threads for step-over.\n");
4659 /* Note, we should always reach here with an already adjusted PC,
4660 either by GDB (if we're resuming due to GDB's request), or by our
4661 caller, if we just finished handling an internal breakpoint GDB
4662 shouldn't care about. */
4665 saved_thread = current_thread;
4666 current_thread = thread;
4668 lwp->bp_reinsert = pc;
4669 uninsert_breakpoints_at (pc);
4670 uninsert_fast_tracepoint_jumps_at (pc);
4672 step = single_step (lwp);
4674 current_thread = saved_thread;
4676 linux_resume_one_lwp (lwp, step, 0, NULL);
4678 /* Require next event from this LWP. */
4679 step_over_bkpt = thread->entry.id;
4683 /* Finish a step-over. Reinsert the breakpoint we had uninserted in
4684 start_step_over, if still there, and delete any reinsert
4685 breakpoints we've set, on non hardware single-step targets. */
4688 finish_step_over (struct lwp_info *lwp)
4690 if (lwp->bp_reinsert != 0)
4693 debug_printf ("Finished step over.\n");
4695 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
4696 may be no breakpoint to reinsert there by now. */
4697 reinsert_breakpoints_at (lwp->bp_reinsert);
4698 reinsert_fast_tracepoint_jumps_at (lwp->bp_reinsert);
4700 lwp->bp_reinsert = 0;
4702 /* Delete any software-single-step reinsert breakpoints. No
4703 longer needed. We don't have to worry about other threads
4704 hitting this trap, and later not being able to explain it,
4705 because we were stepping over a breakpoint, and we hold all
4706 threads but LWP stopped while doing that. */
4707 if (!can_hardware_single_step ())
4708 delete_reinsert_breakpoints ();
4710 step_over_bkpt = null_ptid;
4717 /* If there's a step over in progress, wait until all threads stop
4718 (that is, until the stepping thread finishes its step), and
4719 unsuspend all lwps. The stepping thread ends with its status
4720 pending, which is processed later when we get back to processing
4724 complete_ongoing_step_over (void)
4726 if (!ptid_equal (step_over_bkpt, null_ptid))
4728 struct lwp_info *lwp;
4733 debug_printf ("detach: step over in progress, finish it first\n");
4735 /* Passing NULL_PTID as filter indicates we want all events to
4736 be left pending. Eventually this returns when there are no
4737 unwaited-for children left. */
4738 ret = linux_wait_for_event_filtered (minus_one_ptid, null_ptid,
4740 gdb_assert (ret == -1);
4742 lwp = find_lwp_pid (step_over_bkpt);
4744 finish_step_over (lwp);
4745 step_over_bkpt = null_ptid;
4746 unsuspend_all_lwps (lwp);
4750 /* This function is called once per thread. We check the thread's resume
4751 request, which will tell us whether to resume, step, or leave the thread
4752 stopped; and what signal, if any, it should be sent.
4754 For threads which we aren't explicitly told otherwise, we preserve
4755 the stepping flag; this is used for stepping over gdbserver-placed
4758 If pending_flags was set in any thread, we queue any needed
4759 signals, since we won't actually resume. We already have a pending
4760 event to report, so we don't need to preserve any step requests;
4761 they should be re-issued if necessary. */
4764 linux_resume_one_thread (struct inferior_list_entry *entry, void *arg)
4766 struct thread_info *thread = (struct thread_info *) entry;
4767 struct lwp_info *lwp = get_thread_lwp (thread);
4769 int leave_all_stopped = * (int *) arg;
4772 if (lwp->resume == NULL)
4775 if (lwp->resume->kind == resume_stop)
4778 debug_printf ("resume_stop request for LWP %ld\n", lwpid_of (thread));
4783 debug_printf ("stopping LWP %ld\n", lwpid_of (thread));
4785 /* Stop the thread, and wait for the event asynchronously,
4786 through the event loop. */
4792 debug_printf ("already stopped LWP %ld\n",
4795 /* The LWP may have been stopped in an internal event that
4796 was not meant to be notified back to GDB (e.g., gdbserver
4797 breakpoint), so we should be reporting a stop event in
4800 /* If the thread already has a pending SIGSTOP, this is a
4801 no-op. Otherwise, something later will presumably resume
4802 the thread and this will cause it to cancel any pending
4803 operation, due to last_resume_kind == resume_stop. If
4804 the thread already has a pending status to report, we
4805 will still report it the next time we wait - see
4806 status_pending_p_callback. */
4808 /* If we already have a pending signal to report, then
4809 there's no need to queue a SIGSTOP, as this means we're
4810 midway through moving the LWP out of the jumppad, and we
4811 will report the pending signal as soon as that is
4813 if (lwp->pending_signals_to_report == NULL)
4817 /* For stop requests, we're done. */
4819 thread->last_status.kind = TARGET_WAITKIND_IGNORE;
4823 /* If this thread which is about to be resumed has a pending status,
4824 then don't resume it - we can just report the pending status.
4825 Likewise if it is suspended, because e.g., another thread is
4826 stepping past a breakpoint. Make sure to queue any signals that
4827 would otherwise be sent. In all-stop mode, we do this decision
4828 based on if *any* thread has a pending status. If there's a
4829 thread that needs the step-over-breakpoint dance, then don't
4830 resume any other thread but that particular one. */
4831 leave_pending = (lwp->suspended
4832 || lwp->status_pending_p
4833 || leave_all_stopped);
4838 debug_printf ("resuming LWP %ld\n", lwpid_of (thread));
4840 step = (lwp->resume->kind == resume_step);
4841 linux_resume_one_lwp (lwp, step, lwp->resume->sig, NULL);
4846 debug_printf ("leaving LWP %ld stopped\n", lwpid_of (thread));
4848 /* If we have a new signal, enqueue the signal. */
4849 if (lwp->resume->sig != 0)
4851 struct pending_signals *p_sig = XCNEW (struct pending_signals);
4853 p_sig->prev = lwp->pending_signals;
4854 p_sig->signal = lwp->resume->sig;
4856 /* If this is the same signal we were previously stopped by,
4857 make sure to queue its siginfo. We can ignore the return
4858 value of ptrace; if it fails, we'll skip
4859 PTRACE_SETSIGINFO. */
4860 if (WIFSTOPPED (lwp->last_status)
4861 && WSTOPSIG (lwp->last_status) == lwp->resume->sig)
4862 ptrace (PTRACE_GETSIGINFO, lwpid_of (thread), (PTRACE_TYPE_ARG3) 0,
4865 lwp->pending_signals = p_sig;
4869 thread->last_status.kind = TARGET_WAITKIND_IGNORE;
4875 linux_resume (struct thread_resume *resume_info, size_t n)
4877 struct thread_resume_array array = { resume_info, n };
4878 struct thread_info *need_step_over = NULL;
4880 int leave_all_stopped;
4885 debug_printf ("linux_resume:\n");
4888 find_inferior (&all_threads, linux_set_resume_request, &array);
4890 /* If there is a thread which would otherwise be resumed, which has
4891 a pending status, then don't resume any threads - we can just
4892 report the pending status. Make sure to queue any signals that
4893 would otherwise be sent. In non-stop mode, we'll apply this
4894 logic to each thread individually. We consume all pending events
4895 before considering to start a step-over (in all-stop). */
4898 find_inferior (&all_threads, resume_status_pending_p, &any_pending);
4900 /* If there is a thread which would otherwise be resumed, which is
4901 stopped at a breakpoint that needs stepping over, then don't
4902 resume any threads - have it step over the breakpoint with all
4903 other threads stopped, then resume all threads again. Make sure
4904 to queue any signals that would otherwise be delivered or
4906 if (!any_pending && supports_breakpoints ())
4908 = (struct thread_info *) find_inferior (&all_threads,
4909 need_step_over_p, NULL);
4911 leave_all_stopped = (need_step_over != NULL || any_pending);
4915 if (need_step_over != NULL)
4916 debug_printf ("Not resuming all, need step over\n");
4917 else if (any_pending)
4918 debug_printf ("Not resuming, all-stop and found "
4919 "an LWP with pending status\n");
4921 debug_printf ("Resuming, no pending status or step over needed\n");
4924 /* Even if we're leaving threads stopped, queue all signals we'd
4925 otherwise deliver. */
4926 find_inferior (&all_threads, linux_resume_one_thread, &leave_all_stopped);
4929 start_step_over (get_thread_lwp (need_step_over));
4933 debug_printf ("linux_resume done\n");
4937 /* We may have events that were pending that can/should be sent to
4938 the client now. Trigger a linux_wait call. */
4939 if (target_is_async_p ())
4943 /* This function is called once per thread. We check the thread's
4944 last resume request, which will tell us whether to resume, step, or
4945 leave the thread stopped. Any signal the client requested to be
4946 delivered has already been enqueued at this point.
4948 If any thread that GDB wants running is stopped at an internal
4949 breakpoint that needs stepping over, we start a step-over operation
4950 on that particular thread, and leave all others stopped. */
4953 proceed_one_lwp (struct inferior_list_entry *entry, void *except)
4955 struct thread_info *thread = (struct thread_info *) entry;
4956 struct lwp_info *lwp = get_thread_lwp (thread);
4963 debug_printf ("proceed_one_lwp: lwp %ld\n", lwpid_of (thread));
4968 debug_printf (" LWP %ld already running\n", lwpid_of (thread));
4972 if (thread->last_resume_kind == resume_stop
4973 && thread->last_status.kind != TARGET_WAITKIND_IGNORE)
4976 debug_printf (" client wants LWP to remain %ld stopped\n",
4981 if (lwp->status_pending_p)
4984 debug_printf (" LWP %ld has pending status, leaving stopped\n",
4989 gdb_assert (lwp->suspended >= 0);
4994 debug_printf (" LWP %ld is suspended\n", lwpid_of (thread));
4998 if (thread->last_resume_kind == resume_stop
4999 && lwp->pending_signals_to_report == NULL
5000 && lwp->collecting_fast_tracepoint == 0)
5002 /* We haven't reported this LWP as stopped yet (otherwise, the
5003 last_status.kind check above would catch it, and we wouldn't
5004 reach here. This LWP may have been momentarily paused by a
5005 stop_all_lwps call while handling for example, another LWP's
5006 step-over. In that case, the pending expected SIGSTOP signal
5007 that was queued at vCont;t handling time will have already
5008 been consumed by wait_for_sigstop, and so we need to requeue
5009 another one here. Note that if the LWP already has a SIGSTOP
5010 pending, this is a no-op. */
5013 debug_printf ("Client wants LWP %ld to stop. "
5014 "Making sure it has a SIGSTOP pending\n",
5020 if (thread->last_resume_kind == resume_step)
5023 debug_printf (" stepping LWP %ld, client wants it stepping\n",
5027 else if (lwp->bp_reinsert != 0)
5030 debug_printf (" stepping LWP %ld, reinsert set\n",
5037 linux_resume_one_lwp (lwp, step, 0, NULL);
5042 unsuspend_and_proceed_one_lwp (struct inferior_list_entry *entry, void *except)
5044 struct thread_info *thread = (struct thread_info *) entry;
5045 struct lwp_info *lwp = get_thread_lwp (thread);
5050 lwp_suspended_decr (lwp);
5052 return proceed_one_lwp (entry, except);
5055 /* When we finish a step-over, set threads running again. If there's
5056 another thread that may need a step-over, now's the time to start
5057 it. Eventually, we'll move all threads past their breakpoints. */
5060 proceed_all_lwps (void)
5062 struct thread_info *need_step_over;
5064 /* If there is a thread which would otherwise be resumed, which is
5065 stopped at a breakpoint that needs stepping over, then don't
5066 resume any threads - have it step over the breakpoint with all
5067 other threads stopped, then resume all threads again. */
5069 if (supports_breakpoints ())
5072 = (struct thread_info *) find_inferior (&all_threads,
5073 need_step_over_p, NULL);
5075 if (need_step_over != NULL)
5078 debug_printf ("proceed_all_lwps: found "
5079 "thread %ld needing a step-over\n",
5080 lwpid_of (need_step_over));
5082 start_step_over (get_thread_lwp (need_step_over));
5088 debug_printf ("Proceeding, no step-over needed\n");
5090 find_inferior (&all_threads, proceed_one_lwp, NULL);
5093 /* Stopped LWPs that the client wanted to be running, that don't have
5094 pending statuses, are set to run again, except for EXCEPT, if not
5095 NULL. This undoes a stop_all_lwps call. */
5098 unstop_all_lwps (int unsuspend, struct lwp_info *except)
5104 debug_printf ("unstopping all lwps, except=(LWP %ld)\n",
5105 lwpid_of (get_lwp_thread (except)));
5107 debug_printf ("unstopping all lwps\n");
5111 find_inferior (&all_threads, unsuspend_and_proceed_one_lwp, except);
5113 find_inferior (&all_threads, proceed_one_lwp, except);
5117 debug_printf ("unstop_all_lwps done\n");
5123 #ifdef HAVE_LINUX_REGSETS
5125 #define use_linux_regsets 1
5127 /* Returns true if REGSET has been disabled. */
5130 regset_disabled (struct regsets_info *info, struct regset_info *regset)
5132 return (info->disabled_regsets != NULL
5133 && info->disabled_regsets[regset - info->regsets]);
5136 /* Disable REGSET. */
5139 disable_regset (struct regsets_info *info, struct regset_info *regset)
5143 dr_offset = regset - info->regsets;
5144 if (info->disabled_regsets == NULL)
5145 info->disabled_regsets = (char *) xcalloc (1, info->num_regsets);
5146 info->disabled_regsets[dr_offset] = 1;
5150 regsets_fetch_inferior_registers (struct regsets_info *regsets_info,
5151 struct regcache *regcache)
5153 struct regset_info *regset;
5154 int saw_general_regs = 0;
5158 pid = lwpid_of (current_thread);
5159 for (regset = regsets_info->regsets; regset->size >= 0; regset++)
5164 if (regset->size == 0 || regset_disabled (regsets_info, regset))
5167 buf = xmalloc (regset->size);
5169 nt_type = regset->nt_type;
5173 iov.iov_len = regset->size;
5174 data = (void *) &iov;
5180 res = ptrace (regset->get_request, pid,
5181 (PTRACE_TYPE_ARG3) (long) nt_type, data);
5183 res = ptrace (regset->get_request, pid, data, nt_type);
5189 /* If we get EIO on a regset, do not try it again for
5190 this process mode. */
5191 disable_regset (regsets_info, regset);
5193 else if (errno == ENODATA)
5195 /* ENODATA may be returned if the regset is currently
5196 not "active". This can happen in normal operation,
5197 so suppress the warning in this case. */
5202 sprintf (s, "ptrace(regsets_fetch_inferior_registers) PID=%d",
5209 if (regset->type == GENERAL_REGS)
5210 saw_general_regs = 1;
5211 regset->store_function (regcache, buf);
5215 if (saw_general_regs)
5222 regsets_store_inferior_registers (struct regsets_info *regsets_info,
5223 struct regcache *regcache)
5225 struct regset_info *regset;
5226 int saw_general_regs = 0;
5230 pid = lwpid_of (current_thread);
5231 for (regset = regsets_info->regsets; regset->size >= 0; regset++)
5236 if (regset->size == 0 || regset_disabled (regsets_info, regset)
5237 || regset->fill_function == NULL)
5240 buf = xmalloc (regset->size);
5242 /* First fill the buffer with the current register set contents,
5243 in case there are any items in the kernel's regset that are
5244 not in gdbserver's regcache. */
5246 nt_type = regset->nt_type;
5250 iov.iov_len = regset->size;
5251 data = (void *) &iov;
5257 res = ptrace (regset->get_request, pid,
5258 (PTRACE_TYPE_ARG3) (long) nt_type, data);
5260 res = ptrace (regset->get_request, pid, data, nt_type);
5265 /* Then overlay our cached registers on that. */
5266 regset->fill_function (regcache, buf);
5268 /* Only now do we write the register set. */
5270 res = ptrace (regset->set_request, pid,
5271 (PTRACE_TYPE_ARG3) (long) nt_type, data);
5273 res = ptrace (regset->set_request, pid, data, nt_type);
5281 /* If we get EIO on a regset, do not try it again for
5282 this process mode. */
5283 disable_regset (regsets_info, regset);
5285 else if (errno == ESRCH)
5287 /* At this point, ESRCH should mean the process is
5288 already gone, in which case we simply ignore attempts
5289 to change its registers. See also the related
5290 comment in linux_resume_one_lwp. */
5296 perror ("Warning: ptrace(regsets_store_inferior_registers)");
5299 else if (regset->type == GENERAL_REGS)
5300 saw_general_regs = 1;
5303 if (saw_general_regs)
5309 #else /* !HAVE_LINUX_REGSETS */
5311 #define use_linux_regsets 0
5312 #define regsets_fetch_inferior_registers(regsets_info, regcache) 1
5313 #define regsets_store_inferior_registers(regsets_info, regcache) 1
5317 /* Return 1 if register REGNO is supported by one of the regset ptrace
5318 calls or 0 if it has to be transferred individually. */
5321 linux_register_in_regsets (const struct regs_info *regs_info, int regno)
5323 unsigned char mask = 1 << (regno % 8);
5324 size_t index = regno / 8;
5326 return (use_linux_regsets
5327 && (regs_info->regset_bitmap == NULL
5328 || (regs_info->regset_bitmap[index] & mask) != 0));
5331 #ifdef HAVE_LINUX_USRREGS
5334 register_addr (const struct usrregs_info *usrregs, int regnum)
5338 if (regnum < 0 || regnum >= usrregs->num_regs)
5339 error ("Invalid register number %d.", regnum);
5341 addr = usrregs->regmap[regnum];
5346 /* Fetch one register. */
5348 fetch_register (const struct usrregs_info *usrregs,
5349 struct regcache *regcache, int regno)
5356 if (regno >= usrregs->num_regs)
5358 if ((*the_low_target.cannot_fetch_register) (regno))
5361 regaddr = register_addr (usrregs, regno);
5365 size = ((register_size (regcache->tdesc, regno)
5366 + sizeof (PTRACE_XFER_TYPE) - 1)
5367 & -sizeof (PTRACE_XFER_TYPE));
5368 buf = (char *) alloca (size);
5370 pid = lwpid_of (current_thread);
5371 for (i = 0; i < size; i += sizeof (PTRACE_XFER_TYPE))
5374 *(PTRACE_XFER_TYPE *) (buf + i) =
5375 ptrace (PTRACE_PEEKUSER, pid,
5376 /* Coerce to a uintptr_t first to avoid potential gcc warning
5377 of coercing an 8 byte integer to a 4 byte pointer. */
5378 (PTRACE_TYPE_ARG3) (uintptr_t) regaddr, (PTRACE_TYPE_ARG4) 0);
5379 regaddr += sizeof (PTRACE_XFER_TYPE);
5381 error ("reading register %d: %s", regno, strerror (errno));
5384 if (the_low_target.supply_ptrace_register)
5385 the_low_target.supply_ptrace_register (regcache, regno, buf);
5387 supply_register (regcache, regno, buf);
5390 /* Store one register. */
5392 store_register (const struct usrregs_info *usrregs,
5393 struct regcache *regcache, int regno)
5400 if (regno >= usrregs->num_regs)
5402 if ((*the_low_target.cannot_store_register) (regno))
5405 regaddr = register_addr (usrregs, regno);
5409 size = ((register_size (regcache->tdesc, regno)
5410 + sizeof (PTRACE_XFER_TYPE) - 1)
5411 & -sizeof (PTRACE_XFER_TYPE));
5412 buf = (char *) alloca (size);
5413 memset (buf, 0, size);
5415 if (the_low_target.collect_ptrace_register)
5416 the_low_target.collect_ptrace_register (regcache, regno, buf);
5418 collect_register (regcache, regno, buf);
5420 pid = lwpid_of (current_thread);
5421 for (i = 0; i < size; i += sizeof (PTRACE_XFER_TYPE))
5424 ptrace (PTRACE_POKEUSER, pid,
5425 /* Coerce to a uintptr_t first to avoid potential gcc warning
5426 about coercing an 8 byte integer to a 4 byte pointer. */
5427 (PTRACE_TYPE_ARG3) (uintptr_t) regaddr,
5428 (PTRACE_TYPE_ARG4) *(PTRACE_XFER_TYPE *) (buf + i));
5431 /* At this point, ESRCH should mean the process is
5432 already gone, in which case we simply ignore attempts
5433 to change its registers. See also the related
5434 comment in linux_resume_one_lwp. */
5438 if ((*the_low_target.cannot_store_register) (regno) == 0)
5439 error ("writing register %d: %s", regno, strerror (errno));
5441 regaddr += sizeof (PTRACE_XFER_TYPE);
5445 /* Fetch all registers, or just one, from the child process.
5446 If REGNO is -1, do this for all registers, skipping any that are
5447 assumed to have been retrieved by regsets_fetch_inferior_registers,
5448 unless ALL is non-zero.
5449 Otherwise, REGNO specifies which register (so we can save time). */
5451 usr_fetch_inferior_registers (const struct regs_info *regs_info,
5452 struct regcache *regcache, int regno, int all)
5454 struct usrregs_info *usr = regs_info->usrregs;
5458 for (regno = 0; regno < usr->num_regs; regno++)
5459 if (all || !linux_register_in_regsets (regs_info, regno))
5460 fetch_register (usr, regcache, regno);
5463 fetch_register (usr, regcache, regno);
5466 /* Store our register values back into the inferior.
5467 If REGNO is -1, do this for all registers, skipping any that are
5468 assumed to have been saved by regsets_store_inferior_registers,
5469 unless ALL is non-zero.
5470 Otherwise, REGNO specifies which register (so we can save time). */
5472 usr_store_inferior_registers (const struct regs_info *regs_info,
5473 struct regcache *regcache, int regno, int all)
5475 struct usrregs_info *usr = regs_info->usrregs;
5479 for (regno = 0; regno < usr->num_regs; regno++)
5480 if (all || !linux_register_in_regsets (regs_info, regno))
5481 store_register (usr, regcache, regno);
5484 store_register (usr, regcache, regno);
5487 #else /* !HAVE_LINUX_USRREGS */
5489 #define usr_fetch_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
5490 #define usr_store_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
5496 linux_fetch_registers (struct regcache *regcache, int regno)
5500 const struct regs_info *regs_info = (*the_low_target.regs_info) ();
5504 if (the_low_target.fetch_register != NULL
5505 && regs_info->usrregs != NULL)
5506 for (regno = 0; regno < regs_info->usrregs->num_regs; regno++)
5507 (*the_low_target.fetch_register) (regcache, regno);
5509 all = regsets_fetch_inferior_registers (regs_info->regsets_info, regcache);
5510 if (regs_info->usrregs != NULL)
5511 usr_fetch_inferior_registers (regs_info, regcache, -1, all);
5515 if (the_low_target.fetch_register != NULL
5516 && (*the_low_target.fetch_register) (regcache, regno))
5519 use_regsets = linux_register_in_regsets (regs_info, regno);
5521 all = regsets_fetch_inferior_registers (regs_info->regsets_info,
5523 if ((!use_regsets || all) && regs_info->usrregs != NULL)
5524 usr_fetch_inferior_registers (regs_info, regcache, regno, 1);
5529 linux_store_registers (struct regcache *regcache, int regno)
5533 const struct regs_info *regs_info = (*the_low_target.regs_info) ();
5537 all = regsets_store_inferior_registers (regs_info->regsets_info,
5539 if (regs_info->usrregs != NULL)
5540 usr_store_inferior_registers (regs_info, regcache, regno, all);
5544 use_regsets = linux_register_in_regsets (regs_info, regno);
5546 all = regsets_store_inferior_registers (regs_info->regsets_info,
5548 if ((!use_regsets || all) && regs_info->usrregs != NULL)
5549 usr_store_inferior_registers (regs_info, regcache, regno, 1);
5554 /* Copy LEN bytes from inferior's memory starting at MEMADDR
5555 to debugger memory starting at MYADDR. */
5558 linux_read_memory (CORE_ADDR memaddr, unsigned char *myaddr, int len)
5560 int pid = lwpid_of (current_thread);
5561 register PTRACE_XFER_TYPE *buffer;
5562 register CORE_ADDR addr;
5569 /* Try using /proc. Don't bother for one word. */
5570 if (len >= 3 * sizeof (long))
5574 /* We could keep this file open and cache it - possibly one per
5575 thread. That requires some juggling, but is even faster. */
5576 sprintf (filename, "/proc/%d/mem", pid);
5577 fd = open (filename, O_RDONLY | O_LARGEFILE);
5581 /* If pread64 is available, use it. It's faster if the kernel
5582 supports it (only one syscall), and it's 64-bit safe even on
5583 32-bit platforms (for instance, SPARC debugging a SPARC64
5586 bytes = pread64 (fd, myaddr, len, memaddr);
5589 if (lseek (fd, memaddr, SEEK_SET) != -1)
5590 bytes = read (fd, myaddr, len);
5597 /* Some data was read, we'll try to get the rest with ptrace. */
5607 /* Round starting address down to longword boundary. */
5608 addr = memaddr & -(CORE_ADDR) sizeof (PTRACE_XFER_TYPE);
5609 /* Round ending address up; get number of longwords that makes. */
5610 count = ((((memaddr + len) - addr) + sizeof (PTRACE_XFER_TYPE) - 1)
5611 / sizeof (PTRACE_XFER_TYPE));
5612 /* Allocate buffer of that many longwords. */
5613 buffer = XALLOCAVEC (PTRACE_XFER_TYPE, count);
5615 /* Read all the longwords */
5617 for (i = 0; i < count; i++, addr += sizeof (PTRACE_XFER_TYPE))
5619 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5620 about coercing an 8 byte integer to a 4 byte pointer. */
5621 buffer[i] = ptrace (PTRACE_PEEKTEXT, pid,
5622 (PTRACE_TYPE_ARG3) (uintptr_t) addr,
5623 (PTRACE_TYPE_ARG4) 0);
5629 /* Copy appropriate bytes out of the buffer. */
5632 i *= sizeof (PTRACE_XFER_TYPE);
5633 i -= memaddr & (sizeof (PTRACE_XFER_TYPE) - 1);
5635 (char *) buffer + (memaddr & (sizeof (PTRACE_XFER_TYPE) - 1)),
5642 /* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
5643 memory at MEMADDR. On failure (cannot write to the inferior)
5644 returns the value of errno. Always succeeds if LEN is zero. */
5647 linux_write_memory (CORE_ADDR memaddr, const unsigned char *myaddr, int len)
5650 /* Round starting address down to longword boundary. */
5651 register CORE_ADDR addr = memaddr & -(CORE_ADDR) sizeof (PTRACE_XFER_TYPE);
5652 /* Round ending address up; get number of longwords that makes. */
5654 = (((memaddr + len) - addr) + sizeof (PTRACE_XFER_TYPE) - 1)
5655 / sizeof (PTRACE_XFER_TYPE);
5657 /* Allocate buffer of that many longwords. */
5658 register PTRACE_XFER_TYPE *buffer = XALLOCAVEC (PTRACE_XFER_TYPE, count);
5660 int pid = lwpid_of (current_thread);
5664 /* Zero length write always succeeds. */
5670 /* Dump up to four bytes. */
5671 char str[4 * 2 + 1];
5673 int dump = len < 4 ? len : 4;
5675 for (i = 0; i < dump; i++)
5677 sprintf (p, "%02x", myaddr[i]);
5682 debug_printf ("Writing %s to 0x%08lx in process %d\n",
5683 str, (long) memaddr, pid);
5686 /* Fill start and end extra bytes of buffer with existing memory data. */
5689 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5690 about coercing an 8 byte integer to a 4 byte pointer. */
5691 buffer[0] = ptrace (PTRACE_PEEKTEXT, pid,
5692 (PTRACE_TYPE_ARG3) (uintptr_t) addr,
5693 (PTRACE_TYPE_ARG4) 0);
5701 = ptrace (PTRACE_PEEKTEXT, pid,
5702 /* Coerce to a uintptr_t first to avoid potential gcc warning
5703 about coercing an 8 byte integer to a 4 byte pointer. */
5704 (PTRACE_TYPE_ARG3) (uintptr_t) (addr + (count - 1)
5705 * sizeof (PTRACE_XFER_TYPE)),
5706 (PTRACE_TYPE_ARG4) 0);
5711 /* Copy data to be written over corresponding part of buffer. */
5713 memcpy ((char *) buffer + (memaddr & (sizeof (PTRACE_XFER_TYPE) - 1)),
5716 /* Write the entire buffer. */
5718 for (i = 0; i < count; i++, addr += sizeof (PTRACE_XFER_TYPE))
5721 ptrace (PTRACE_POKETEXT, pid,
5722 /* Coerce to a uintptr_t first to avoid potential gcc warning
5723 about coercing an 8 byte integer to a 4 byte pointer. */
5724 (PTRACE_TYPE_ARG3) (uintptr_t) addr,
5725 (PTRACE_TYPE_ARG4) buffer[i]);
5734 linux_look_up_symbols (void)
5736 #ifdef USE_THREAD_DB
5737 struct process_info *proc = current_process ();
5739 if (proc->priv->thread_db != NULL)
5747 linux_request_interrupt (void)
5749 extern unsigned long signal_pid;
5751 /* Send a SIGINT to the process group. This acts just like the user
5752 typed a ^C on the controlling terminal. */
5753 kill (-signal_pid, SIGINT);
5756 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
5757 to debugger memory starting at MYADDR. */
5760 linux_read_auxv (CORE_ADDR offset, unsigned char *myaddr, unsigned int len)
5762 char filename[PATH_MAX];
5764 int pid = lwpid_of (current_thread);
5766 xsnprintf (filename, sizeof filename, "/proc/%d/auxv", pid);
5768 fd = open (filename, O_RDONLY);
5772 if (offset != (CORE_ADDR) 0
5773 && lseek (fd, (off_t) offset, SEEK_SET) != (off_t) offset)
5776 n = read (fd, myaddr, len);
5783 /* These breakpoint and watchpoint related wrapper functions simply
5784 pass on the function call if the target has registered a
5785 corresponding function. */
5788 linux_supports_z_point_type (char z_type)
5790 return (the_low_target.supports_z_point_type != NULL
5791 && the_low_target.supports_z_point_type (z_type));
5795 linux_insert_point (enum raw_bkpt_type type, CORE_ADDR addr,
5796 int size, struct raw_breakpoint *bp)
5798 if (type == raw_bkpt_type_sw)
5799 return insert_memory_breakpoint (bp);
5800 else if (the_low_target.insert_point != NULL)
5801 return the_low_target.insert_point (type, addr, size, bp);
5803 /* Unsupported (see target.h). */
5808 linux_remove_point (enum raw_bkpt_type type, CORE_ADDR addr,
5809 int size, struct raw_breakpoint *bp)
5811 if (type == raw_bkpt_type_sw)
5812 return remove_memory_breakpoint (bp);
5813 else if (the_low_target.remove_point != NULL)
5814 return the_low_target.remove_point (type, addr, size, bp);
5816 /* Unsupported (see target.h). */
5820 /* Implement the to_stopped_by_sw_breakpoint target_ops
5824 linux_stopped_by_sw_breakpoint (void)
5826 struct lwp_info *lwp = get_thread_lwp (current_thread);
5828 return (lwp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT);
5831 /* Implement the to_supports_stopped_by_sw_breakpoint target_ops
5835 linux_supports_stopped_by_sw_breakpoint (void)
5837 return USE_SIGTRAP_SIGINFO;
5840 /* Implement the to_stopped_by_hw_breakpoint target_ops
5844 linux_stopped_by_hw_breakpoint (void)
5846 struct lwp_info *lwp = get_thread_lwp (current_thread);
5848 return (lwp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT);
5851 /* Implement the to_supports_stopped_by_hw_breakpoint target_ops
5855 linux_supports_stopped_by_hw_breakpoint (void)
5857 return USE_SIGTRAP_SIGINFO;
5860 /* Implement the supports_hardware_single_step target_ops method. */
5863 linux_supports_hardware_single_step (void)
5865 return can_hardware_single_step ();
5869 linux_supports_software_single_step (void)
5871 return can_software_single_step ();
5875 linux_stopped_by_watchpoint (void)
5877 struct lwp_info *lwp = get_thread_lwp (current_thread);
5879 return lwp->stop_reason == TARGET_STOPPED_BY_WATCHPOINT;
5883 linux_stopped_data_address (void)
5885 struct lwp_info *lwp = get_thread_lwp (current_thread);
5887 return lwp->stopped_data_address;
5890 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
5891 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
5892 && defined(PT_TEXT_END_ADDR)
5894 /* This is only used for targets that define PT_TEXT_ADDR,
5895 PT_DATA_ADDR and PT_TEXT_END_ADDR. If those are not defined, supposedly
5896 the target has different ways of acquiring this information, like
5899 /* Under uClinux, programs are loaded at non-zero offsets, which we need
5900 to tell gdb about. */
5903 linux_read_offsets (CORE_ADDR *text_p, CORE_ADDR *data_p)
5905 unsigned long text, text_end, data;
5906 int pid = lwpid_of (current_thread);
5910 text = ptrace (PTRACE_PEEKUSER, pid, (PTRACE_TYPE_ARG3) PT_TEXT_ADDR,
5911 (PTRACE_TYPE_ARG4) 0);
5912 text_end = ptrace (PTRACE_PEEKUSER, pid, (PTRACE_TYPE_ARG3) PT_TEXT_END_ADDR,
5913 (PTRACE_TYPE_ARG4) 0);
5914 data = ptrace (PTRACE_PEEKUSER, pid, (PTRACE_TYPE_ARG3) PT_DATA_ADDR,
5915 (PTRACE_TYPE_ARG4) 0);
5919 /* Both text and data offsets produced at compile-time (and so
5920 used by gdb) are relative to the beginning of the program,
5921 with the data segment immediately following the text segment.
5922 However, the actual runtime layout in memory may put the data
5923 somewhere else, so when we send gdb a data base-address, we
5924 use the real data base address and subtract the compile-time
5925 data base-address from it (which is just the length of the
5926 text segment). BSS immediately follows data in both
5929 *data_p = data - (text_end - text);
5938 linux_qxfer_osdata (const char *annex,
5939 unsigned char *readbuf, unsigned const char *writebuf,
5940 CORE_ADDR offset, int len)
5942 return linux_common_xfer_osdata (annex, readbuf, offset, len);
5945 /* Convert a native/host siginfo object, into/from the siginfo in the
5946 layout of the inferiors' architecture. */
5949 siginfo_fixup (siginfo_t *siginfo, gdb_byte *inf_siginfo, int direction)
5953 if (the_low_target.siginfo_fixup != NULL)
5954 done = the_low_target.siginfo_fixup (siginfo, inf_siginfo, direction);
5956 /* If there was no callback, or the callback didn't do anything,
5957 then just do a straight memcpy. */
5961 memcpy (siginfo, inf_siginfo, sizeof (siginfo_t));
5963 memcpy (inf_siginfo, siginfo, sizeof (siginfo_t));
5968 linux_xfer_siginfo (const char *annex, unsigned char *readbuf,
5969 unsigned const char *writebuf, CORE_ADDR offset, int len)
5973 gdb_byte inf_siginfo[sizeof (siginfo_t)];
5975 if (current_thread == NULL)
5978 pid = lwpid_of (current_thread);
5981 debug_printf ("%s siginfo for lwp %d.\n",
5982 readbuf != NULL ? "Reading" : "Writing",
5985 if (offset >= sizeof (siginfo))
5988 if (ptrace (PTRACE_GETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo) != 0)
5991 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
5992 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
5993 inferior with a 64-bit GDBSERVER should look the same as debugging it
5994 with a 32-bit GDBSERVER, we need to convert it. */
5995 siginfo_fixup (&siginfo, inf_siginfo, 0);
5997 if (offset + len > sizeof (siginfo))
5998 len = sizeof (siginfo) - offset;
6000 if (readbuf != NULL)
6001 memcpy (readbuf, inf_siginfo + offset, len);
6004 memcpy (inf_siginfo + offset, writebuf, len);
6006 /* Convert back to ptrace layout before flushing it out. */
6007 siginfo_fixup (&siginfo, inf_siginfo, 1);
6009 if (ptrace (PTRACE_SETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo) != 0)
6016 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
6017 so we notice when children change state; as the handler for the
6018 sigsuspend in my_waitpid. */
6021 sigchld_handler (int signo)
6023 int old_errno = errno;
6029 /* fprintf is not async-signal-safe, so call write
6031 if (write (2, "sigchld_handler\n",
6032 sizeof ("sigchld_handler\n") - 1) < 0)
6033 break; /* just ignore */
6037 if (target_is_async_p ())
6038 async_file_mark (); /* trigger a linux_wait */
6044 linux_supports_non_stop (void)
6050 linux_async (int enable)
6052 int previous = target_is_async_p ();
6055 debug_printf ("linux_async (%d), previous=%d\n",
6058 if (previous != enable)
6061 sigemptyset (&mask);
6062 sigaddset (&mask, SIGCHLD);
6064 sigprocmask (SIG_BLOCK, &mask, NULL);
6068 if (pipe (linux_event_pipe) == -1)
6070 linux_event_pipe[0] = -1;
6071 linux_event_pipe[1] = -1;
6072 sigprocmask (SIG_UNBLOCK, &mask, NULL);
6074 warning ("creating event pipe failed.");
6078 fcntl (linux_event_pipe[0], F_SETFL, O_NONBLOCK);
6079 fcntl (linux_event_pipe[1], F_SETFL, O_NONBLOCK);
6081 /* Register the event loop handler. */
6082 add_file_handler (linux_event_pipe[0],
6083 handle_target_event, NULL);
6085 /* Always trigger a linux_wait. */
6090 delete_file_handler (linux_event_pipe[0]);
6092 close (linux_event_pipe[0]);
6093 close (linux_event_pipe[1]);
6094 linux_event_pipe[0] = -1;
6095 linux_event_pipe[1] = -1;
6098 sigprocmask (SIG_UNBLOCK, &mask, NULL);
6105 linux_start_non_stop (int nonstop)
6107 /* Register or unregister from event-loop accordingly. */
6108 linux_async (nonstop);
6110 if (target_is_async_p () != (nonstop != 0))
6117 linux_supports_multi_process (void)
6122 /* Check if fork events are supported. */
6125 linux_supports_fork_events (void)
6127 return linux_supports_tracefork ();
6130 /* Check if vfork events are supported. */
6133 linux_supports_vfork_events (void)
6135 return linux_supports_tracefork ();
6138 /* Check if exec events are supported. */
6141 linux_supports_exec_events (void)
6143 return linux_supports_traceexec ();
6146 /* Callback for 'find_inferior'. Set the (possibly changed) ptrace
6147 options for the specified lwp. */
6150 reset_lwp_ptrace_options_callback (struct inferior_list_entry *entry,
6153 struct thread_info *thread = (struct thread_info *) entry;
6154 struct lwp_info *lwp = get_thread_lwp (thread);
6158 /* Stop the lwp so we can modify its ptrace options. */
6159 lwp->must_set_ptrace_flags = 1;
6160 linux_stop_lwp (lwp);
6164 /* Already stopped; go ahead and set the ptrace options. */
6165 struct process_info *proc = find_process_pid (pid_of (thread));
6166 int options = linux_low_ptrace_options (proc->attached);
6168 linux_enable_event_reporting (lwpid_of (thread), options);
6169 lwp->must_set_ptrace_flags = 0;
6175 /* Target hook for 'handle_new_gdb_connection'. Causes a reset of the
6176 ptrace flags for all inferiors. This is in case the new GDB connection
6177 doesn't support the same set of events that the previous one did. */
6180 linux_handle_new_gdb_connection (void)
6184 /* Request that all the lwps reset their ptrace options. */
6185 find_inferior (&all_threads, reset_lwp_ptrace_options_callback , &pid);
6189 linux_supports_disable_randomization (void)
6191 #ifdef HAVE_PERSONALITY
6199 linux_supports_agent (void)
6205 linux_supports_range_stepping (void)
6207 if (*the_low_target.supports_range_stepping == NULL)
6210 return (*the_low_target.supports_range_stepping) ();
6213 /* Enumerate spufs IDs for process PID. */
6215 spu_enumerate_spu_ids (long pid, unsigned char *buf, CORE_ADDR offset, int len)
6221 struct dirent *entry;
6223 sprintf (path, "/proc/%ld/fd", pid);
6224 dir = opendir (path);
6229 while ((entry = readdir (dir)) != NULL)
6235 fd = atoi (entry->d_name);
6239 sprintf (path, "/proc/%ld/fd/%d", pid, fd);
6240 if (stat (path, &st) != 0)
6242 if (!S_ISDIR (st.st_mode))
6245 if (statfs (path, &stfs) != 0)
6247 if (stfs.f_type != SPUFS_MAGIC)
6250 if (pos >= offset && pos + 4 <= offset + len)
6252 *(unsigned int *)(buf + pos - offset) = fd;
6262 /* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
6263 object type, using the /proc file system. */
6265 linux_qxfer_spu (const char *annex, unsigned char *readbuf,
6266 unsigned const char *writebuf,
6267 CORE_ADDR offset, int len)
6269 long pid = lwpid_of (current_thread);
6274 if (!writebuf && !readbuf)
6282 return spu_enumerate_spu_ids (pid, readbuf, offset, len);
6285 sprintf (buf, "/proc/%ld/fd/%s", pid, annex);
6286 fd = open (buf, writebuf? O_WRONLY : O_RDONLY);
6291 && lseek (fd, (off_t) offset, SEEK_SET) != (off_t) offset)
6298 ret = write (fd, writebuf, (size_t) len);
6300 ret = read (fd, readbuf, (size_t) len);
6306 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
6307 struct target_loadseg
6309 /* Core address to which the segment is mapped. */
6311 /* VMA recorded in the program header. */
6313 /* Size of this segment in memory. */
6317 # if defined PT_GETDSBT
6318 struct target_loadmap
6320 /* Protocol version number, must be zero. */
6322 /* Pointer to the DSBT table, its size, and the DSBT index. */
6323 unsigned *dsbt_table;
6324 unsigned dsbt_size, dsbt_index;
6325 /* Number of segments in this map. */
6327 /* The actual memory map. */
6328 struct target_loadseg segs[/*nsegs*/];
6330 # define LINUX_LOADMAP PT_GETDSBT
6331 # define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
6332 # define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
6334 struct target_loadmap
6336 /* Protocol version number, must be zero. */
6338 /* Number of segments in this map. */
6340 /* The actual memory map. */
6341 struct target_loadseg segs[/*nsegs*/];
6343 # define LINUX_LOADMAP PTRACE_GETFDPIC
6344 # define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
6345 # define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
6349 linux_read_loadmap (const char *annex, CORE_ADDR offset,
6350 unsigned char *myaddr, unsigned int len)
6352 int pid = lwpid_of (current_thread);
6354 struct target_loadmap *data = NULL;
6355 unsigned int actual_length, copy_length;
6357 if (strcmp (annex, "exec") == 0)
6358 addr = (int) LINUX_LOADMAP_EXEC;
6359 else if (strcmp (annex, "interp") == 0)
6360 addr = (int) LINUX_LOADMAP_INTERP;
6364 if (ptrace (LINUX_LOADMAP, pid, addr, &data) != 0)
6370 actual_length = sizeof (struct target_loadmap)
6371 + sizeof (struct target_loadseg) * data->nsegs;
6373 if (offset < 0 || offset > actual_length)
6376 copy_length = actual_length - offset < len ? actual_length - offset : len;
6377 memcpy (myaddr, (char *) data + offset, copy_length);
6381 # define linux_read_loadmap NULL
6382 #endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
6385 linux_process_qsupported (char **features, int count)
6387 if (the_low_target.process_qsupported != NULL)
6388 the_low_target.process_qsupported (features, count);
6392 linux_supports_catch_syscall (void)
6394 return (the_low_target.get_syscall_trapinfo != NULL
6395 && linux_supports_tracesysgood ());
6399 linux_get_ipa_tdesc_idx (void)
6401 if (the_low_target.get_ipa_tdesc_idx == NULL)
6404 return (*the_low_target.get_ipa_tdesc_idx) ();
6408 linux_supports_tracepoints (void)
6410 if (*the_low_target.supports_tracepoints == NULL)
6413 return (*the_low_target.supports_tracepoints) ();
6417 linux_read_pc (struct regcache *regcache)
6419 if (the_low_target.get_pc == NULL)
6422 return (*the_low_target.get_pc) (regcache);
6426 linux_write_pc (struct regcache *regcache, CORE_ADDR pc)
6428 gdb_assert (the_low_target.set_pc != NULL);
6430 (*the_low_target.set_pc) (regcache, pc);
6434 linux_thread_stopped (struct thread_info *thread)
6436 return get_thread_lwp (thread)->stopped;
6439 /* This exposes stop-all-threads functionality to other modules. */
6442 linux_pause_all (int freeze)
6444 stop_all_lwps (freeze, NULL);
6447 /* This exposes unstop-all-threads functionality to other gdbserver
6451 linux_unpause_all (int unfreeze)
6453 unstop_all_lwps (unfreeze, NULL);
6457 linux_prepare_to_access_memory (void)
6459 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6462 linux_pause_all (1);
6467 linux_done_accessing_memory (void)
6469 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6472 linux_unpause_all (1);
6476 linux_install_fast_tracepoint_jump_pad (CORE_ADDR tpoint, CORE_ADDR tpaddr,
6477 CORE_ADDR collector,
6480 CORE_ADDR *jump_entry,
6481 CORE_ADDR *trampoline,
6482 ULONGEST *trampoline_size,
6483 unsigned char *jjump_pad_insn,
6484 ULONGEST *jjump_pad_insn_size,
6485 CORE_ADDR *adjusted_insn_addr,
6486 CORE_ADDR *adjusted_insn_addr_end,
6489 return (*the_low_target.install_fast_tracepoint_jump_pad)
6490 (tpoint, tpaddr, collector, lockaddr, orig_size,
6491 jump_entry, trampoline, trampoline_size,
6492 jjump_pad_insn, jjump_pad_insn_size,
6493 adjusted_insn_addr, adjusted_insn_addr_end,
6497 static struct emit_ops *
6498 linux_emit_ops (void)
6500 if (the_low_target.emit_ops != NULL)
6501 return (*the_low_target.emit_ops) ();
6507 linux_get_min_fast_tracepoint_insn_len (void)
6509 return (*the_low_target.get_min_fast_tracepoint_insn_len) ();
6512 /* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
6515 get_phdr_phnum_from_proc_auxv (const int pid, const int is_elf64,
6516 CORE_ADDR *phdr_memaddr, int *num_phdr)
6518 char filename[PATH_MAX];
6520 const int auxv_size = is_elf64
6521 ? sizeof (Elf64_auxv_t) : sizeof (Elf32_auxv_t);
6522 char buf[sizeof (Elf64_auxv_t)]; /* The larger of the two. */
6524 xsnprintf (filename, sizeof filename, "/proc/%d/auxv", pid);
6526 fd = open (filename, O_RDONLY);
6532 while (read (fd, buf, auxv_size) == auxv_size
6533 && (*phdr_memaddr == 0 || *num_phdr == 0))
6537 Elf64_auxv_t *const aux = (Elf64_auxv_t *) buf;
6539 switch (aux->a_type)
6542 *phdr_memaddr = aux->a_un.a_val;
6545 *num_phdr = aux->a_un.a_val;
6551 Elf32_auxv_t *const aux = (Elf32_auxv_t *) buf;
6553 switch (aux->a_type)
6556 *phdr_memaddr = aux->a_un.a_val;
6559 *num_phdr = aux->a_un.a_val;
6567 if (*phdr_memaddr == 0 || *num_phdr == 0)
6569 warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
6570 "phdr_memaddr = %ld, phdr_num = %d",
6571 (long) *phdr_memaddr, *num_phdr);
6578 /* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
6581 get_dynamic (const int pid, const int is_elf64)
6583 CORE_ADDR phdr_memaddr, relocation;
6585 unsigned char *phdr_buf;
6586 const int phdr_size = is_elf64 ? sizeof (Elf64_Phdr) : sizeof (Elf32_Phdr);
6588 if (get_phdr_phnum_from_proc_auxv (pid, is_elf64, &phdr_memaddr, &num_phdr))
6591 gdb_assert (num_phdr < 100); /* Basic sanity check. */
6592 phdr_buf = (unsigned char *) alloca (num_phdr * phdr_size);
6594 if (linux_read_memory (phdr_memaddr, phdr_buf, num_phdr * phdr_size))
6597 /* Compute relocation: it is expected to be 0 for "regular" executables,
6598 non-zero for PIE ones. */
6600 for (i = 0; relocation == -1 && i < num_phdr; i++)
6603 Elf64_Phdr *const p = (Elf64_Phdr *) (phdr_buf + i * phdr_size);
6605 if (p->p_type == PT_PHDR)
6606 relocation = phdr_memaddr - p->p_vaddr;
6610 Elf32_Phdr *const p = (Elf32_Phdr *) (phdr_buf + i * phdr_size);
6612 if (p->p_type == PT_PHDR)
6613 relocation = phdr_memaddr - p->p_vaddr;
6616 if (relocation == -1)
6618 /* PT_PHDR is optional, but necessary for PIE in general. Fortunately
6619 any real world executables, including PIE executables, have always
6620 PT_PHDR present. PT_PHDR is not present in some shared libraries or
6621 in fpc (Free Pascal 2.4) binaries but neither of those have a need for
6622 or present DT_DEBUG anyway (fpc binaries are statically linked).
6624 Therefore if there exists DT_DEBUG there is always also PT_PHDR.
6626 GDB could find RELOCATION also from AT_ENTRY - e_entry. */
6631 for (i = 0; i < num_phdr; i++)
6635 Elf64_Phdr *const p = (Elf64_Phdr *) (phdr_buf + i * phdr_size);
6637 if (p->p_type == PT_DYNAMIC)
6638 return p->p_vaddr + relocation;
6642 Elf32_Phdr *const p = (Elf32_Phdr *) (phdr_buf + i * phdr_size);
6644 if (p->p_type == PT_DYNAMIC)
6645 return p->p_vaddr + relocation;
6652 /* Return &_r_debug in the inferior, or -1 if not present. Return value
6653 can be 0 if the inferior does not yet have the library list initialized.
6654 We look for DT_MIPS_RLD_MAP first. MIPS executables use this instead of
6655 DT_DEBUG, although they sometimes contain an unused DT_DEBUG entry too. */
6658 get_r_debug (const int pid, const int is_elf64)
6660 CORE_ADDR dynamic_memaddr;
6661 const int dyn_size = is_elf64 ? sizeof (Elf64_Dyn) : sizeof (Elf32_Dyn);
6662 unsigned char buf[sizeof (Elf64_Dyn)]; /* The larger of the two. */
6665 dynamic_memaddr = get_dynamic (pid, is_elf64);
6666 if (dynamic_memaddr == 0)
6669 while (linux_read_memory (dynamic_memaddr, buf, dyn_size) == 0)
6673 Elf64_Dyn *const dyn = (Elf64_Dyn *) buf;
6674 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
6678 unsigned char buf[sizeof (Elf64_Xword)];
6682 #ifdef DT_MIPS_RLD_MAP
6683 if (dyn->d_tag == DT_MIPS_RLD_MAP)
6685 if (linux_read_memory (dyn->d_un.d_val,
6686 rld_map.buf, sizeof (rld_map.buf)) == 0)
6691 #endif /* DT_MIPS_RLD_MAP */
6692 #ifdef DT_MIPS_RLD_MAP_REL
6693 if (dyn->d_tag == DT_MIPS_RLD_MAP_REL)
6695 if (linux_read_memory (dyn->d_un.d_val + dynamic_memaddr,
6696 rld_map.buf, sizeof (rld_map.buf)) == 0)
6701 #endif /* DT_MIPS_RLD_MAP_REL */
6703 if (dyn->d_tag == DT_DEBUG && map == -1)
6704 map = dyn->d_un.d_val;
6706 if (dyn->d_tag == DT_NULL)
6711 Elf32_Dyn *const dyn = (Elf32_Dyn *) buf;
6712 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
6716 unsigned char buf[sizeof (Elf32_Word)];
6720 #ifdef DT_MIPS_RLD_MAP
6721 if (dyn->d_tag == DT_MIPS_RLD_MAP)
6723 if (linux_read_memory (dyn->d_un.d_val,
6724 rld_map.buf, sizeof (rld_map.buf)) == 0)
6729 #endif /* DT_MIPS_RLD_MAP */
6730 #ifdef DT_MIPS_RLD_MAP_REL
6731 if (dyn->d_tag == DT_MIPS_RLD_MAP_REL)
6733 if (linux_read_memory (dyn->d_un.d_val + dynamic_memaddr,
6734 rld_map.buf, sizeof (rld_map.buf)) == 0)
6739 #endif /* DT_MIPS_RLD_MAP_REL */
6741 if (dyn->d_tag == DT_DEBUG && map == -1)
6742 map = dyn->d_un.d_val;
6744 if (dyn->d_tag == DT_NULL)
6748 dynamic_memaddr += dyn_size;
6754 /* Read one pointer from MEMADDR in the inferior. */
6757 read_one_ptr (CORE_ADDR memaddr, CORE_ADDR *ptr, int ptr_size)
6761 /* Go through a union so this works on either big or little endian
6762 hosts, when the inferior's pointer size is smaller than the size
6763 of CORE_ADDR. It is assumed the inferior's endianness is the
6764 same of the superior's. */
6767 CORE_ADDR core_addr;
6772 ret = linux_read_memory (memaddr, &addr.uc, ptr_size);
6775 if (ptr_size == sizeof (CORE_ADDR))
6776 *ptr = addr.core_addr;
6777 else if (ptr_size == sizeof (unsigned int))
6780 gdb_assert_not_reached ("unhandled pointer size");
6785 struct link_map_offsets
6787 /* Offset and size of r_debug.r_version. */
6788 int r_version_offset;
6790 /* Offset and size of r_debug.r_map. */
6793 /* Offset to l_addr field in struct link_map. */
6796 /* Offset to l_name field in struct link_map. */
6799 /* Offset to l_ld field in struct link_map. */
6802 /* Offset to l_next field in struct link_map. */
6805 /* Offset to l_prev field in struct link_map. */
6809 /* Construct qXfer:libraries-svr4:read reply. */
6812 linux_qxfer_libraries_svr4 (const char *annex, unsigned char *readbuf,
6813 unsigned const char *writebuf,
6814 CORE_ADDR offset, int len)
6817 unsigned document_len;
6818 struct process_info_private *const priv = current_process ()->priv;
6819 char filename[PATH_MAX];
6822 static const struct link_map_offsets lmo_32bit_offsets =
6824 0, /* r_version offset. */
6825 4, /* r_debug.r_map offset. */
6826 0, /* l_addr offset in link_map. */
6827 4, /* l_name offset in link_map. */
6828 8, /* l_ld offset in link_map. */
6829 12, /* l_next offset in link_map. */
6830 16 /* l_prev offset in link_map. */
6833 static const struct link_map_offsets lmo_64bit_offsets =
6835 0, /* r_version offset. */
6836 8, /* r_debug.r_map offset. */
6837 0, /* l_addr offset in link_map. */
6838 8, /* l_name offset in link_map. */
6839 16, /* l_ld offset in link_map. */
6840 24, /* l_next offset in link_map. */
6841 32 /* l_prev offset in link_map. */
6843 const struct link_map_offsets *lmo;
6844 unsigned int machine;
6846 CORE_ADDR lm_addr = 0, lm_prev = 0;
6847 int allocated = 1024;
6849 CORE_ADDR l_name, l_addr, l_ld, l_next, l_prev;
6850 int header_done = 0;
6852 if (writebuf != NULL)
6854 if (readbuf == NULL)
6857 pid = lwpid_of (current_thread);
6858 xsnprintf (filename, sizeof filename, "/proc/%d/exe", pid);
6859 is_elf64 = elf_64_file_p (filename, &machine);
6860 lmo = is_elf64 ? &lmo_64bit_offsets : &lmo_32bit_offsets;
6861 ptr_size = is_elf64 ? 8 : 4;
6863 while (annex[0] != '\0')
6869 sep = strchr (annex, '=');
6874 if (len == 5 && startswith (annex, "start"))
6876 else if (len == 4 && startswith (annex, "prev"))
6880 annex = strchr (sep, ';');
6887 annex = decode_address_to_semicolon (addrp, sep + 1);
6894 if (priv->r_debug == 0)
6895 priv->r_debug = get_r_debug (pid, is_elf64);
6897 /* We failed to find DT_DEBUG. Such situation will not change
6898 for this inferior - do not retry it. Report it to GDB as
6899 E01, see for the reasons at the GDB solib-svr4.c side. */
6900 if (priv->r_debug == (CORE_ADDR) -1)
6903 if (priv->r_debug != 0)
6905 if (linux_read_memory (priv->r_debug + lmo->r_version_offset,
6906 (unsigned char *) &r_version,
6907 sizeof (r_version)) != 0
6910 warning ("unexpected r_debug version %d", r_version);
6912 else if (read_one_ptr (priv->r_debug + lmo->r_map_offset,
6913 &lm_addr, ptr_size) != 0)
6915 warning ("unable to read r_map from 0x%lx",
6916 (long) priv->r_debug + lmo->r_map_offset);
6921 document = (char *) xmalloc (allocated);
6922 strcpy (document, "<library-list-svr4 version=\"1.0\"");
6923 p = document + strlen (document);
6926 && read_one_ptr (lm_addr + lmo->l_name_offset,
6927 &l_name, ptr_size) == 0
6928 && read_one_ptr (lm_addr + lmo->l_addr_offset,
6929 &l_addr, ptr_size) == 0
6930 && read_one_ptr (lm_addr + lmo->l_ld_offset,
6931 &l_ld, ptr_size) == 0
6932 && read_one_ptr (lm_addr + lmo->l_prev_offset,
6933 &l_prev, ptr_size) == 0
6934 && read_one_ptr (lm_addr + lmo->l_next_offset,
6935 &l_next, ptr_size) == 0)
6937 unsigned char libname[PATH_MAX];
6939 if (lm_prev != l_prev)
6941 warning ("Corrupted shared library list: 0x%lx != 0x%lx",
6942 (long) lm_prev, (long) l_prev);
6946 /* Ignore the first entry even if it has valid name as the first entry
6947 corresponds to the main executable. The first entry should not be
6948 skipped if the dynamic loader was loaded late by a static executable
6949 (see solib-svr4.c parameter ignore_first). But in such case the main
6950 executable does not have PT_DYNAMIC present and this function already
6951 exited above due to failed get_r_debug. */
6954 sprintf (p, " main-lm=\"0x%lx\"", (unsigned long) lm_addr);
6959 /* Not checking for error because reading may stop before
6960 we've got PATH_MAX worth of characters. */
6962 linux_read_memory (l_name, libname, sizeof (libname) - 1);
6963 libname[sizeof (libname) - 1] = '\0';
6964 if (libname[0] != '\0')
6966 /* 6x the size for xml_escape_text below. */
6967 size_t len = 6 * strlen ((char *) libname);
6972 /* Terminate `<library-list-svr4'. */
6977 while (allocated < p - document + len + 200)
6979 /* Expand to guarantee sufficient storage. */
6980 uintptr_t document_len = p - document;
6982 document = (char *) xrealloc (document, 2 * allocated);
6984 p = document + document_len;
6987 name = xml_escape_text ((char *) libname);
6988 p += sprintf (p, "<library name=\"%s\" lm=\"0x%lx\" "
6989 "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
6990 name, (unsigned long) lm_addr,
6991 (unsigned long) l_addr, (unsigned long) l_ld);
7002 /* Empty list; terminate `<library-list-svr4'. */
7006 strcpy (p, "</library-list-svr4>");
7008 document_len = strlen (document);
7009 if (offset < document_len)
7010 document_len -= offset;
7013 if (len > document_len)
7016 memcpy (readbuf, document + offset, len);
7022 #ifdef HAVE_LINUX_BTRACE
7024 /* See to_disable_btrace target method. */
7027 linux_low_disable_btrace (struct btrace_target_info *tinfo)
7029 enum btrace_error err;
7031 err = linux_disable_btrace (tinfo);
7032 return (err == BTRACE_ERR_NONE ? 0 : -1);
7035 /* Encode an Intel Processor Trace configuration. */
7038 linux_low_encode_pt_config (struct buffer *buffer,
7039 const struct btrace_data_pt_config *config)
7041 buffer_grow_str (buffer, "<pt-config>\n");
7043 switch (config->cpu.vendor)
7046 buffer_xml_printf (buffer, "<cpu vendor=\"GenuineIntel\" family=\"%u\" "
7047 "model=\"%u\" stepping=\"%u\"/>\n",
7048 config->cpu.family, config->cpu.model,
7049 config->cpu.stepping);
7056 buffer_grow_str (buffer, "</pt-config>\n");
7059 /* Encode a raw buffer. */
7062 linux_low_encode_raw (struct buffer *buffer, const gdb_byte *data,
7068 /* We use hex encoding - see common/rsp-low.h. */
7069 buffer_grow_str (buffer, "<raw>\n");
7075 elem[0] = tohex ((*data >> 4) & 0xf);
7076 elem[1] = tohex (*data++ & 0xf);
7078 buffer_grow (buffer, elem, 2);
7081 buffer_grow_str (buffer, "</raw>\n");
7084 /* See to_read_btrace target method. */
7087 linux_low_read_btrace (struct btrace_target_info *tinfo, struct buffer *buffer,
7088 enum btrace_read_type type)
7090 struct btrace_data btrace;
7091 struct btrace_block *block;
7092 enum btrace_error err;
7095 btrace_data_init (&btrace);
7097 err = linux_read_btrace (&btrace, tinfo, type);
7098 if (err != BTRACE_ERR_NONE)
7100 if (err == BTRACE_ERR_OVERFLOW)
7101 buffer_grow_str0 (buffer, "E.Overflow.");
7103 buffer_grow_str0 (buffer, "E.Generic Error.");
7108 switch (btrace.format)
7110 case BTRACE_FORMAT_NONE:
7111 buffer_grow_str0 (buffer, "E.No Trace.");
7114 case BTRACE_FORMAT_BTS:
7115 buffer_grow_str (buffer, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
7116 buffer_grow_str (buffer, "<btrace version=\"1.0\">\n");
7119 VEC_iterate (btrace_block_s, btrace.variant.bts.blocks, i, block);
7121 buffer_xml_printf (buffer, "<block begin=\"0x%s\" end=\"0x%s\"/>\n",
7122 paddress (block->begin), paddress (block->end));
7124 buffer_grow_str0 (buffer, "</btrace>\n");
7127 case BTRACE_FORMAT_PT:
7128 buffer_grow_str (buffer, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
7129 buffer_grow_str (buffer, "<btrace version=\"1.0\">\n");
7130 buffer_grow_str (buffer, "<pt>\n");
7132 linux_low_encode_pt_config (buffer, &btrace.variant.pt.config);
7134 linux_low_encode_raw (buffer, btrace.variant.pt.data,
7135 btrace.variant.pt.size);
7137 buffer_grow_str (buffer, "</pt>\n");
7138 buffer_grow_str0 (buffer, "</btrace>\n");
7142 buffer_grow_str0 (buffer, "E.Unsupported Trace Format.");
7146 btrace_data_fini (&btrace);
7150 btrace_data_fini (&btrace);
7154 /* See to_btrace_conf target method. */
7157 linux_low_btrace_conf (const struct btrace_target_info *tinfo,
7158 struct buffer *buffer)
7160 const struct btrace_config *conf;
7162 buffer_grow_str (buffer, "<!DOCTYPE btrace-conf SYSTEM \"btrace-conf.dtd\">\n");
7163 buffer_grow_str (buffer, "<btrace-conf version=\"1.0\">\n");
7165 conf = linux_btrace_conf (tinfo);
7168 switch (conf->format)
7170 case BTRACE_FORMAT_NONE:
7173 case BTRACE_FORMAT_BTS:
7174 buffer_xml_printf (buffer, "<bts");
7175 buffer_xml_printf (buffer, " size=\"0x%x\"", conf->bts.size);
7176 buffer_xml_printf (buffer, " />\n");
7179 case BTRACE_FORMAT_PT:
7180 buffer_xml_printf (buffer, "<pt");
7181 buffer_xml_printf (buffer, " size=\"0x%x\"", conf->pt.size);
7182 buffer_xml_printf (buffer, "/>\n");
7187 buffer_grow_str0 (buffer, "</btrace-conf>\n");
7190 #endif /* HAVE_LINUX_BTRACE */
7192 /* See nat/linux-nat.h. */
7195 current_lwp_ptid (void)
7197 return ptid_of (current_thread);
7200 /* Implementation of the target_ops method "breakpoint_kind_from_pc". */
7203 linux_breakpoint_kind_from_pc (CORE_ADDR *pcptr)
7205 if (the_low_target.breakpoint_kind_from_pc != NULL)
7206 return (*the_low_target.breakpoint_kind_from_pc) (pcptr);
7208 return default_breakpoint_kind_from_pc (pcptr);
7211 /* Implementation of the target_ops method "sw_breakpoint_from_kind". */
7213 static const gdb_byte *
7214 linux_sw_breakpoint_from_kind (int kind, int *size)
7216 gdb_assert (the_low_target.sw_breakpoint_from_kind != NULL);
7218 return (*the_low_target.sw_breakpoint_from_kind) (kind, size);
7221 /* Implementation of the target_ops method
7222 "breakpoint_kind_from_current_state". */
7225 linux_breakpoint_kind_from_current_state (CORE_ADDR *pcptr)
7227 if (the_low_target.breakpoint_kind_from_current_state != NULL)
7228 return (*the_low_target.breakpoint_kind_from_current_state) (pcptr);
7230 return linux_breakpoint_kind_from_pc (pcptr);
7233 /* Default implementation of linux_target_ops method "set_pc" for
7234 32-bit pc register which is literally named "pc". */
7237 linux_set_pc_32bit (struct regcache *regcache, CORE_ADDR pc)
7239 uint32_t newpc = pc;
7241 supply_register_by_name (regcache, "pc", &newpc);
7244 /* Default implementation of linux_target_ops method "get_pc" for
7245 32-bit pc register which is literally named "pc". */
7248 linux_get_pc_32bit (struct regcache *regcache)
7252 collect_register_by_name (regcache, "pc", &pc);
7254 debug_printf ("stop pc is 0x%" PRIx32 "\n", pc);
7258 /* Default implementation of linux_target_ops method "set_pc" for
7259 64-bit pc register which is literally named "pc". */
7262 linux_set_pc_64bit (struct regcache *regcache, CORE_ADDR pc)
7264 uint64_t newpc = pc;
7266 supply_register_by_name (regcache, "pc", &newpc);
7269 /* Default implementation of linux_target_ops method "get_pc" for
7270 64-bit pc register which is literally named "pc". */
7273 linux_get_pc_64bit (struct regcache *regcache)
7277 collect_register_by_name (regcache, "pc", &pc);
7279 debug_printf ("stop pc is 0x%" PRIx64 "\n", pc);
7284 static struct target_ops linux_target_ops = {
7285 linux_create_inferior,
7286 linux_post_create_inferior,
7295 linux_fetch_registers,
7296 linux_store_registers,
7297 linux_prepare_to_access_memory,
7298 linux_done_accessing_memory,
7301 linux_look_up_symbols,
7302 linux_request_interrupt,
7304 linux_supports_z_point_type,
7307 linux_stopped_by_sw_breakpoint,
7308 linux_supports_stopped_by_sw_breakpoint,
7309 linux_stopped_by_hw_breakpoint,
7310 linux_supports_stopped_by_hw_breakpoint,
7311 linux_supports_hardware_single_step,
7312 linux_stopped_by_watchpoint,
7313 linux_stopped_data_address,
7314 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
7315 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
7316 && defined(PT_TEXT_END_ADDR)
7321 #ifdef USE_THREAD_DB
7322 thread_db_get_tls_address,
7327 hostio_last_error_from_errno,
7330 linux_supports_non_stop,
7332 linux_start_non_stop,
7333 linux_supports_multi_process,
7334 linux_supports_fork_events,
7335 linux_supports_vfork_events,
7336 linux_supports_exec_events,
7337 linux_handle_new_gdb_connection,
7338 #ifdef USE_THREAD_DB
7339 thread_db_handle_monitor_command,
7343 linux_common_core_of_thread,
7345 linux_process_qsupported,
7346 linux_supports_tracepoints,
7349 linux_thread_stopped,
7353 linux_stabilize_threads,
7354 linux_install_fast_tracepoint_jump_pad,
7356 linux_supports_disable_randomization,
7357 linux_get_min_fast_tracepoint_insn_len,
7358 linux_qxfer_libraries_svr4,
7359 linux_supports_agent,
7360 #ifdef HAVE_LINUX_BTRACE
7361 linux_supports_btrace,
7362 linux_enable_btrace,
7363 linux_low_disable_btrace,
7364 linux_low_read_btrace,
7365 linux_low_btrace_conf,
7373 linux_supports_range_stepping,
7374 linux_proc_pid_to_exec_file,
7375 linux_mntns_open_cloexec,
7377 linux_mntns_readlink,
7378 linux_breakpoint_kind_from_pc,
7379 linux_sw_breakpoint_from_kind,
7380 linux_proc_tid_get_name,
7381 linux_breakpoint_kind_from_current_state,
7382 linux_supports_software_single_step,
7383 linux_supports_catch_syscall,
7384 linux_get_ipa_tdesc_idx,
7387 #ifdef HAVE_LINUX_REGSETS
7389 initialize_regsets_info (struct regsets_info *info)
7391 for (info->num_regsets = 0;
7392 info->regsets[info->num_regsets].size >= 0;
7393 info->num_regsets++)
7399 initialize_low (void)
7401 struct sigaction sigchld_action;
7403 memset (&sigchld_action, 0, sizeof (sigchld_action));
7404 set_target_ops (&linux_target_ops);
7406 linux_ptrace_init_warnings ();
7408 sigchld_action.sa_handler = sigchld_handler;
7409 sigemptyset (&sigchld_action.sa_mask);
7410 sigchld_action.sa_flags = SA_RESTART;
7411 sigaction (SIGCHLD, &sigchld_action, NULL);
7413 initialize_low_arch ();
7415 linux_check_ptrace_features ();