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 void unsuspend_all_lwps (struct lwp_info *except);
256 static int linux_wait_for_event_filtered (ptid_t wait_ptid, ptid_t filter_ptid,
257 int *wstat, int options);
258 static int linux_wait_for_event (ptid_t ptid, int *wstat, int options);
259 static struct lwp_info *add_lwp (ptid_t ptid);
260 static void linux_mourn (struct process_info *process);
261 static int linux_stopped_by_watchpoint (void);
262 static void mark_lwp_dead (struct lwp_info *lwp, int wstat);
263 static int lwp_is_marked_dead (struct lwp_info *lwp);
264 static void proceed_all_lwps (void);
265 static int finish_step_over (struct lwp_info *lwp);
266 static int kill_lwp (unsigned long lwpid, int signo);
267 static void enqueue_pending_signal (struct lwp_info *lwp, int signal, siginfo_t *info);
268 static void complete_ongoing_step_over (void);
269 static int linux_low_ptrace_options (int attached);
271 /* When the event-loop is doing a step-over, this points at the thread
273 ptid_t step_over_bkpt;
275 /* True if the low target can hardware single-step. */
278 can_hardware_single_step (void)
280 if (the_low_target.supports_hardware_single_step != NULL)
281 return the_low_target.supports_hardware_single_step ();
286 /* True if the low target can software single-step. Such targets
287 implement the GET_NEXT_PCS callback. */
290 can_software_single_step (void)
292 return (the_low_target.get_next_pcs != NULL);
295 /* True if the low target supports memory breakpoints. If so, we'll
296 have a GET_PC implementation. */
299 supports_breakpoints (void)
301 return (the_low_target.get_pc != NULL);
304 /* Returns true if this target can support fast tracepoints. This
305 does not mean that the in-process agent has been loaded in the
309 supports_fast_tracepoints (void)
311 return the_low_target.install_fast_tracepoint_jump_pad != NULL;
314 /* True if LWP is stopped in its stepping range. */
317 lwp_in_step_range (struct lwp_info *lwp)
319 CORE_ADDR pc = lwp->stop_pc;
321 return (pc >= lwp->step_range_start && pc < lwp->step_range_end);
324 struct pending_signals
328 struct pending_signals *prev;
331 /* The read/write ends of the pipe registered as waitable file in the
333 static int linux_event_pipe[2] = { -1, -1 };
335 /* True if we're currently in async mode. */
336 #define target_is_async_p() (linux_event_pipe[0] != -1)
338 static void send_sigstop (struct lwp_info *lwp);
339 static void wait_for_sigstop (void);
341 /* Return non-zero if HEADER is a 64-bit ELF file. */
344 elf_64_header_p (const Elf64_Ehdr *header, unsigned int *machine)
346 if (header->e_ident[EI_MAG0] == ELFMAG0
347 && header->e_ident[EI_MAG1] == ELFMAG1
348 && header->e_ident[EI_MAG2] == ELFMAG2
349 && header->e_ident[EI_MAG3] == ELFMAG3)
351 *machine = header->e_machine;
352 return header->e_ident[EI_CLASS] == ELFCLASS64;
359 /* Return non-zero if FILE is a 64-bit ELF file,
360 zero if the file is not a 64-bit ELF file,
361 and -1 if the file is not accessible or doesn't exist. */
364 elf_64_file_p (const char *file, unsigned int *machine)
369 fd = open (file, O_RDONLY);
373 if (read (fd, &header, sizeof (header)) != sizeof (header))
380 return elf_64_header_p (&header, machine);
383 /* Accepts an integer PID; Returns true if the executable PID is
384 running is a 64-bit ELF file.. */
387 linux_pid_exe_is_elf_64_file (int pid, unsigned int *machine)
391 sprintf (file, "/proc/%d/exe", pid);
392 return elf_64_file_p (file, machine);
396 delete_lwp (struct lwp_info *lwp)
398 struct thread_info *thr = get_lwp_thread (lwp);
401 debug_printf ("deleting %ld\n", lwpid_of (thr));
404 free (lwp->arch_private);
408 /* Add a process to the common process list, and set its private
411 static struct process_info *
412 linux_add_process (int pid, int attached)
414 struct process_info *proc;
416 proc = add_process (pid, attached);
417 proc->priv = XCNEW (struct process_info_private);
419 if (the_low_target.new_process != NULL)
420 proc->priv->arch_private = the_low_target.new_process ();
425 static CORE_ADDR get_pc (struct lwp_info *lwp);
427 /* Call the target arch_setup function on the current thread. */
430 linux_arch_setup (void)
432 the_low_target.arch_setup ();
435 /* Call the target arch_setup function on THREAD. */
438 linux_arch_setup_thread (struct thread_info *thread)
440 struct thread_info *saved_thread;
442 saved_thread = current_thread;
443 current_thread = thread;
447 current_thread = saved_thread;
450 /* Handle a GNU/Linux extended wait response. If we see a clone,
451 fork, or vfork event, we need to add the new LWP to our list
452 (and return 0 so as not to report the trap to higher layers).
453 If we see an exec event, we will modify ORIG_EVENT_LWP to point
454 to a new LWP representing the new program. */
457 handle_extended_wait (struct lwp_info **orig_event_lwp, int wstat)
459 struct lwp_info *event_lwp = *orig_event_lwp;
460 int event = linux_ptrace_get_extended_event (wstat);
461 struct thread_info *event_thr = get_lwp_thread (event_lwp);
462 struct lwp_info *new_lwp;
464 gdb_assert (event_lwp->waitstatus.kind == TARGET_WAITKIND_IGNORE);
466 /* All extended events we currently use are mid-syscall. Only
467 PTRACE_EVENT_STOP is delivered more like a signal-stop, but
468 you have to be using PTRACE_SEIZE to get that. */
469 event_lwp->syscall_state = TARGET_WAITKIND_SYSCALL_ENTRY;
471 if ((event == PTRACE_EVENT_FORK) || (event == PTRACE_EVENT_VFORK)
472 || (event == PTRACE_EVENT_CLONE))
475 unsigned long new_pid;
478 /* Get the pid of the new lwp. */
479 ptrace (PTRACE_GETEVENTMSG, lwpid_of (event_thr), (PTRACE_TYPE_ARG3) 0,
482 /* If we haven't already seen the new PID stop, wait for it now. */
483 if (!pull_pid_from_list (&stopped_pids, new_pid, &status))
485 /* The new child has a pending SIGSTOP. We can't affect it until it
486 hits the SIGSTOP, but we're already attached. */
488 ret = my_waitpid (new_pid, &status, __WALL);
491 perror_with_name ("waiting for new child");
492 else if (ret != new_pid)
493 warning ("wait returned unexpected PID %d", ret);
494 else if (!WIFSTOPPED (status))
495 warning ("wait returned unexpected status 0x%x", status);
498 if (event == PTRACE_EVENT_FORK || event == PTRACE_EVENT_VFORK)
500 struct process_info *parent_proc;
501 struct process_info *child_proc;
502 struct lwp_info *child_lwp;
503 struct thread_info *child_thr;
504 struct target_desc *tdesc;
506 ptid = ptid_build (new_pid, new_pid, 0);
510 debug_printf ("HEW: Got fork event from LWP %ld, "
512 ptid_get_lwp (ptid_of (event_thr)),
513 ptid_get_pid (ptid));
516 /* Add the new process to the tables and clone the breakpoint
517 lists of the parent. We need to do this even if the new process
518 will be detached, since we will need the process object and the
519 breakpoints to remove any breakpoints from memory when we
520 detach, and the client side will access registers. */
521 child_proc = linux_add_process (new_pid, 0);
522 gdb_assert (child_proc != NULL);
523 child_lwp = add_lwp (ptid);
524 gdb_assert (child_lwp != NULL);
525 child_lwp->stopped = 1;
526 child_lwp->must_set_ptrace_flags = 1;
527 child_lwp->status_pending_p = 0;
528 child_thr = get_lwp_thread (child_lwp);
529 child_thr->last_resume_kind = resume_stop;
530 child_thr->last_status.kind = TARGET_WAITKIND_STOPPED;
532 /* If we're suspending all threads, leave this one suspended
533 too. If the fork/clone parent is stepping over a breakpoint,
534 all other threads have been suspended already. Leave the
535 child suspended too. */
536 if (stopping_threads == STOPPING_AND_SUSPENDING_THREADS
537 || event_lwp->bp_reinsert != 0)
540 debug_printf ("HEW: leaving child suspended\n");
541 child_lwp->suspended = 1;
544 parent_proc = get_thread_process (event_thr);
545 child_proc->attached = parent_proc->attached;
546 clone_all_breakpoints (&child_proc->breakpoints,
547 &child_proc->raw_breakpoints,
548 parent_proc->breakpoints);
550 tdesc = XNEW (struct target_desc);
551 copy_target_description (tdesc, parent_proc->tdesc);
552 child_proc->tdesc = tdesc;
554 /* Clone arch-specific process data. */
555 if (the_low_target.new_fork != NULL)
556 the_low_target.new_fork (parent_proc, child_proc);
558 /* Save fork info in the parent thread. */
559 if (event == PTRACE_EVENT_FORK)
560 event_lwp->waitstatus.kind = TARGET_WAITKIND_FORKED;
561 else if (event == PTRACE_EVENT_VFORK)
562 event_lwp->waitstatus.kind = TARGET_WAITKIND_VFORKED;
564 event_lwp->waitstatus.value.related_pid = ptid;
566 /* The status_pending field contains bits denoting the
567 extended event, so when the pending event is handled,
568 the handler will look at lwp->waitstatus. */
569 event_lwp->status_pending_p = 1;
570 event_lwp->status_pending = wstat;
572 /* If the parent thread is doing step-over with reinsert
573 breakpoints, the reinsert breakpoints are still in forked
574 child's process space and cloned to its breakpoint list
575 from the parent's. Remove them from the child process. */
576 if (event_lwp->bp_reinsert != 0
577 && can_software_single_step ()
578 && event == PTRACE_EVENT_FORK)
580 struct thread_info *saved_thread = current_thread;
582 /* The child process is forked and stopped, so it is safe
583 to access its memory without stopping all other threads
584 from other processes. */
585 current_thread = child_thr;
586 delete_reinsert_breakpoints ();
587 current_thread = saved_thread;
589 gdb_assert (has_reinsert_breakpoints (parent_proc));
590 gdb_assert (!has_reinsert_breakpoints (child_proc));
593 /* Report the event. */
598 debug_printf ("HEW: Got clone event "
599 "from LWP %ld, new child is LWP %ld\n",
600 lwpid_of (event_thr), new_pid);
602 ptid = ptid_build (pid_of (event_thr), new_pid, 0);
603 new_lwp = add_lwp (ptid);
605 /* Either we're going to immediately resume the new thread
606 or leave it stopped. linux_resume_one_lwp is a nop if it
607 thinks the thread is currently running, so set this first
608 before calling linux_resume_one_lwp. */
609 new_lwp->stopped = 1;
611 /* If we're suspending all threads, leave this one suspended
612 too. If the fork/clone parent is stepping over a breakpoint,
613 all other threads have been suspended already. Leave the
614 child suspended too. */
615 if (stopping_threads == STOPPING_AND_SUSPENDING_THREADS
616 || event_lwp->bp_reinsert != 0)
617 new_lwp->suspended = 1;
619 /* Normally we will get the pending SIGSTOP. But in some cases
620 we might get another signal delivered to the group first.
621 If we do get another signal, be sure not to lose it. */
622 if (WSTOPSIG (status) != SIGSTOP)
624 new_lwp->stop_expected = 1;
625 new_lwp->status_pending_p = 1;
626 new_lwp->status_pending = status;
628 else if (report_thread_events)
630 new_lwp->waitstatus.kind = TARGET_WAITKIND_THREAD_CREATED;
631 new_lwp->status_pending_p = 1;
632 new_lwp->status_pending = status;
635 /* Don't report the event. */
638 else if (event == PTRACE_EVENT_VFORK_DONE)
640 event_lwp->waitstatus.kind = TARGET_WAITKIND_VFORK_DONE;
642 /* Report the event. */
645 else if (event == PTRACE_EVENT_EXEC && report_exec_events)
647 struct process_info *proc;
648 VEC (int) *syscalls_to_catch;
654 debug_printf ("HEW: Got exec event from LWP %ld\n",
655 lwpid_of (event_thr));
658 /* Get the event ptid. */
659 event_ptid = ptid_of (event_thr);
660 event_pid = ptid_get_pid (event_ptid);
662 /* Save the syscall list from the execing process. */
663 proc = get_thread_process (event_thr);
664 syscalls_to_catch = proc->syscalls_to_catch;
665 proc->syscalls_to_catch = NULL;
667 /* Delete the execing process and all its threads. */
669 current_thread = NULL;
671 /* Create a new process/lwp/thread. */
672 proc = linux_add_process (event_pid, 0);
673 event_lwp = add_lwp (event_ptid);
674 event_thr = get_lwp_thread (event_lwp);
675 gdb_assert (current_thread == event_thr);
676 linux_arch_setup_thread (event_thr);
678 /* Set the event status. */
679 event_lwp->waitstatus.kind = TARGET_WAITKIND_EXECD;
680 event_lwp->waitstatus.value.execd_pathname
681 = xstrdup (linux_proc_pid_to_exec_file (lwpid_of (event_thr)));
683 /* Mark the exec status as pending. */
684 event_lwp->stopped = 1;
685 event_lwp->status_pending_p = 1;
686 event_lwp->status_pending = wstat;
687 event_thr->last_resume_kind = resume_continue;
688 event_thr->last_status.kind = TARGET_WAITKIND_IGNORE;
690 /* Update syscall state in the new lwp, effectively mid-syscall too. */
691 event_lwp->syscall_state = TARGET_WAITKIND_SYSCALL_ENTRY;
693 /* Restore the list to catch. Don't rely on the client, which is free
694 to avoid sending a new list when the architecture doesn't change.
695 Also, for ANY_SYSCALL, the architecture doesn't really matter. */
696 proc->syscalls_to_catch = syscalls_to_catch;
698 /* Report the event. */
699 *orig_event_lwp = event_lwp;
703 internal_error (__FILE__, __LINE__, _("unknown ptrace event %d"), event);
706 /* Return the PC as read from the regcache of LWP, without any
710 get_pc (struct lwp_info *lwp)
712 struct thread_info *saved_thread;
713 struct regcache *regcache;
716 if (the_low_target.get_pc == NULL)
719 saved_thread = current_thread;
720 current_thread = get_lwp_thread (lwp);
722 regcache = get_thread_regcache (current_thread, 1);
723 pc = (*the_low_target.get_pc) (regcache);
726 debug_printf ("pc is 0x%lx\n", (long) pc);
728 current_thread = saved_thread;
732 /* This function should only be called if LWP got a SYSCALL_SIGTRAP.
733 Fill *SYSNO with the syscall nr trapped. Fill *SYSRET with the
737 get_syscall_trapinfo (struct lwp_info *lwp, int *sysno, int *sysret)
739 struct thread_info *saved_thread;
740 struct regcache *regcache;
742 if (the_low_target.get_syscall_trapinfo == NULL)
744 /* If we cannot get the syscall trapinfo, report an unknown
745 system call number and -ENOSYS return value. */
746 *sysno = UNKNOWN_SYSCALL;
751 saved_thread = current_thread;
752 current_thread = get_lwp_thread (lwp);
754 regcache = get_thread_regcache (current_thread, 1);
755 (*the_low_target.get_syscall_trapinfo) (regcache, sysno, sysret);
759 debug_printf ("get_syscall_trapinfo sysno %d sysret %d\n",
763 current_thread = saved_thread;
766 static int check_stopped_by_watchpoint (struct lwp_info *child);
768 /* Called when the LWP stopped for a signal/trap. If it stopped for a
769 trap check what caused it (breakpoint, watchpoint, trace, etc.),
770 and save the result in the LWP's stop_reason field. If it stopped
771 for a breakpoint, decrement the PC if necessary on the lwp's
772 architecture. Returns true if we now have the LWP's stop PC. */
775 save_stop_reason (struct lwp_info *lwp)
778 CORE_ADDR sw_breakpoint_pc;
779 struct thread_info *saved_thread;
780 #if USE_SIGTRAP_SIGINFO
784 if (the_low_target.get_pc == NULL)
788 sw_breakpoint_pc = pc - the_low_target.decr_pc_after_break;
790 /* breakpoint_at reads from the current thread. */
791 saved_thread = current_thread;
792 current_thread = get_lwp_thread (lwp);
794 #if USE_SIGTRAP_SIGINFO
795 if (ptrace (PTRACE_GETSIGINFO, lwpid_of (current_thread),
796 (PTRACE_TYPE_ARG3) 0, &siginfo) == 0)
798 if (siginfo.si_signo == SIGTRAP)
800 if (GDB_ARCH_IS_TRAP_BRKPT (siginfo.si_code)
801 && GDB_ARCH_IS_TRAP_HWBKPT (siginfo.si_code))
803 /* The si_code is ambiguous on this arch -- check debug
805 if (!check_stopped_by_watchpoint (lwp))
806 lwp->stop_reason = TARGET_STOPPED_BY_SW_BREAKPOINT;
808 else if (GDB_ARCH_IS_TRAP_BRKPT (siginfo.si_code))
810 /* If we determine the LWP stopped for a SW breakpoint,
811 trust it. Particularly don't check watchpoint
812 registers, because at least on s390, we'd find
813 stopped-by-watchpoint as long as there's a watchpoint
815 lwp->stop_reason = TARGET_STOPPED_BY_SW_BREAKPOINT;
817 else if (GDB_ARCH_IS_TRAP_HWBKPT (siginfo.si_code))
819 /* This can indicate either a hardware breakpoint or
820 hardware watchpoint. Check debug registers. */
821 if (!check_stopped_by_watchpoint (lwp))
822 lwp->stop_reason = TARGET_STOPPED_BY_HW_BREAKPOINT;
824 else if (siginfo.si_code == TRAP_TRACE)
826 /* We may have single stepped an instruction that
827 triggered a watchpoint. In that case, on some
828 architectures (such as x86), instead of TRAP_HWBKPT,
829 si_code indicates TRAP_TRACE, and we need to check
830 the debug registers separately. */
831 if (!check_stopped_by_watchpoint (lwp))
832 lwp->stop_reason = TARGET_STOPPED_BY_SINGLE_STEP;
837 /* We may have just stepped a breakpoint instruction. E.g., in
838 non-stop mode, GDB first tells the thread A to step a range, and
839 then the user inserts a breakpoint inside the range. In that
840 case we need to report the breakpoint PC. */
841 if ((!lwp->stepping || lwp->stop_pc == sw_breakpoint_pc)
842 && (*the_low_target.breakpoint_at) (sw_breakpoint_pc))
843 lwp->stop_reason = TARGET_STOPPED_BY_SW_BREAKPOINT;
845 if (hardware_breakpoint_inserted_here (pc))
846 lwp->stop_reason = TARGET_STOPPED_BY_HW_BREAKPOINT;
848 if (lwp->stop_reason == TARGET_STOPPED_BY_NO_REASON)
849 check_stopped_by_watchpoint (lwp);
852 if (lwp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT)
856 struct thread_info *thr = get_lwp_thread (lwp);
858 debug_printf ("CSBB: %s stopped by software breakpoint\n",
859 target_pid_to_str (ptid_of (thr)));
862 /* Back up the PC if necessary. */
863 if (pc != sw_breakpoint_pc)
865 struct regcache *regcache
866 = get_thread_regcache (current_thread, 1);
867 (*the_low_target.set_pc) (regcache, sw_breakpoint_pc);
870 /* Update this so we record the correct stop PC below. */
871 pc = sw_breakpoint_pc;
873 else if (lwp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT)
877 struct thread_info *thr = get_lwp_thread (lwp);
879 debug_printf ("CSBB: %s stopped by hardware breakpoint\n",
880 target_pid_to_str (ptid_of (thr)));
883 else if (lwp->stop_reason == TARGET_STOPPED_BY_WATCHPOINT)
887 struct thread_info *thr = get_lwp_thread (lwp);
889 debug_printf ("CSBB: %s stopped by hardware watchpoint\n",
890 target_pid_to_str (ptid_of (thr)));
893 else if (lwp->stop_reason == TARGET_STOPPED_BY_SINGLE_STEP)
897 struct thread_info *thr = get_lwp_thread (lwp);
899 debug_printf ("CSBB: %s stopped by trace\n",
900 target_pid_to_str (ptid_of (thr)));
905 current_thread = saved_thread;
909 static struct lwp_info *
910 add_lwp (ptid_t ptid)
912 struct lwp_info *lwp;
914 lwp = XCNEW (struct lwp_info);
916 lwp->waitstatus.kind = TARGET_WAITKIND_IGNORE;
918 if (the_low_target.new_thread != NULL)
919 the_low_target.new_thread (lwp);
921 lwp->thread = add_thread (ptid, lwp);
926 /* Start an inferior process and returns its pid.
927 ALLARGS is a vector of program-name and args. */
930 linux_create_inferior (char *program, char **allargs)
932 struct lwp_info *new_lwp;
935 struct cleanup *restore_personality
936 = maybe_disable_address_space_randomization (disable_randomization);
938 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
944 perror_with_name ("fork");
949 ptrace (PTRACE_TRACEME, 0, (PTRACE_TYPE_ARG3) 0, (PTRACE_TYPE_ARG4) 0);
953 /* If gdbserver is connected to gdb via stdio, redirect the inferior's
954 stdout to stderr so that inferior i/o doesn't corrupt the connection.
955 Also, redirect stdin to /dev/null. */
956 if (remote_connection_is_stdio ())
959 open ("/dev/null", O_RDONLY);
961 if (write (2, "stdin/stdout redirected\n",
962 sizeof ("stdin/stdout redirected\n") - 1) < 0)
964 /* Errors ignored. */;
968 execv (program, allargs);
970 execvp (program, allargs);
972 fprintf (stderr, "Cannot exec %s: %s.\n", program,
978 do_cleanups (restore_personality);
980 linux_add_process (pid, 0);
982 ptid = ptid_build (pid, pid, 0);
983 new_lwp = add_lwp (ptid);
984 new_lwp->must_set_ptrace_flags = 1;
989 /* Implement the post_create_inferior target_ops method. */
992 linux_post_create_inferior (void)
994 struct lwp_info *lwp = get_thread_lwp (current_thread);
998 if (lwp->must_set_ptrace_flags)
1000 struct process_info *proc = current_process ();
1001 int options = linux_low_ptrace_options (proc->attached);
1003 linux_enable_event_reporting (lwpid_of (current_thread), options);
1004 lwp->must_set_ptrace_flags = 0;
1008 /* Attach to an inferior process. Returns 0 on success, ERRNO on
1012 linux_attach_lwp (ptid_t ptid)
1014 struct lwp_info *new_lwp;
1015 int lwpid = ptid_get_lwp (ptid);
1017 if (ptrace (PTRACE_ATTACH, lwpid, (PTRACE_TYPE_ARG3) 0, (PTRACE_TYPE_ARG4) 0)
1021 new_lwp = add_lwp (ptid);
1023 /* We need to wait for SIGSTOP before being able to make the next
1024 ptrace call on this LWP. */
1025 new_lwp->must_set_ptrace_flags = 1;
1027 if (linux_proc_pid_is_stopped (lwpid))
1030 debug_printf ("Attached to a stopped process\n");
1032 /* The process is definitely stopped. It is in a job control
1033 stop, unless the kernel predates the TASK_STOPPED /
1034 TASK_TRACED distinction, in which case it might be in a
1035 ptrace stop. Make sure it is in a ptrace stop; from there we
1036 can kill it, signal it, et cetera.
1038 First make sure there is a pending SIGSTOP. Since we are
1039 already attached, the process can not transition from stopped
1040 to running without a PTRACE_CONT; so we know this signal will
1041 go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
1042 probably already in the queue (unless this kernel is old
1043 enough to use TASK_STOPPED for ptrace stops); but since
1044 SIGSTOP is not an RT signal, it can only be queued once. */
1045 kill_lwp (lwpid, SIGSTOP);
1047 /* Finally, resume the stopped process. This will deliver the
1048 SIGSTOP (or a higher priority signal, just like normal
1049 PTRACE_ATTACH), which we'll catch later on. */
1050 ptrace (PTRACE_CONT, lwpid, (PTRACE_TYPE_ARG3) 0, (PTRACE_TYPE_ARG4) 0);
1053 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
1054 brings it to a halt.
1056 There are several cases to consider here:
1058 1) gdbserver has already attached to the process and is being notified
1059 of a new thread that is being created.
1060 In this case we should ignore that SIGSTOP and resume the
1061 process. This is handled below by setting stop_expected = 1,
1062 and the fact that add_thread sets last_resume_kind ==
1065 2) This is the first thread (the process thread), and we're attaching
1066 to it via attach_inferior.
1067 In this case we want the process thread to stop.
1068 This is handled by having linux_attach set last_resume_kind ==
1069 resume_stop after we return.
1071 If the pid we are attaching to is also the tgid, we attach to and
1072 stop all the existing threads. Otherwise, we attach to pid and
1073 ignore any other threads in the same group as this pid.
1075 3) GDB is connecting to gdbserver and is requesting an enumeration of all
1077 In this case we want the thread to stop.
1078 FIXME: This case is currently not properly handled.
1079 We should wait for the SIGSTOP but don't. Things work apparently
1080 because enough time passes between when we ptrace (ATTACH) and when
1081 gdb makes the next ptrace call on the thread.
1083 On the other hand, if we are currently trying to stop all threads, we
1084 should treat the new thread as if we had sent it a SIGSTOP. This works
1085 because we are guaranteed that the add_lwp call above added us to the
1086 end of the list, and so the new thread has not yet reached
1087 wait_for_sigstop (but will). */
1088 new_lwp->stop_expected = 1;
1093 /* Callback for linux_proc_attach_tgid_threads. Attach to PTID if not
1094 already attached. Returns true if a new LWP is found, false
1098 attach_proc_task_lwp_callback (ptid_t ptid)
1100 /* Is this a new thread? */
1101 if (find_thread_ptid (ptid) == NULL)
1103 int lwpid = ptid_get_lwp (ptid);
1107 debug_printf ("Found new lwp %d\n", lwpid);
1109 err = linux_attach_lwp (ptid);
1111 /* Be quiet if we simply raced with the thread exiting. EPERM
1112 is returned if the thread's task still exists, and is marked
1113 as exited or zombie, as well as other conditions, so in that
1114 case, confirm the status in /proc/PID/status. */
1116 || (err == EPERM && linux_proc_pid_is_gone (lwpid)))
1120 debug_printf ("Cannot attach to lwp %d: "
1121 "thread is gone (%d: %s)\n",
1122 lwpid, err, strerror (err));
1127 warning (_("Cannot attach to lwp %d: %s"),
1129 linux_ptrace_attach_fail_reason_string (ptid, err));
1137 static void async_file_mark (void);
1139 /* Attach to PID. If PID is the tgid, attach to it and all
1143 linux_attach (unsigned long pid)
1145 struct process_info *proc;
1146 struct thread_info *initial_thread;
1147 ptid_t ptid = ptid_build (pid, pid, 0);
1150 /* Attach to PID. We will check for other threads
1152 err = linux_attach_lwp (ptid);
1154 error ("Cannot attach to process %ld: %s",
1155 pid, linux_ptrace_attach_fail_reason_string (ptid, err));
1157 proc = linux_add_process (pid, 1);
1159 /* Don't ignore the initial SIGSTOP if we just attached to this
1160 process. It will be collected by wait shortly. */
1161 initial_thread = find_thread_ptid (ptid_build (pid, pid, 0));
1162 initial_thread->last_resume_kind = resume_stop;
1164 /* We must attach to every LWP. If /proc is mounted, use that to
1165 find them now. On the one hand, the inferior may be using raw
1166 clone instead of using pthreads. On the other hand, even if it
1167 is using pthreads, GDB may not be connected yet (thread_db needs
1168 to do symbol lookups, through qSymbol). Also, thread_db walks
1169 structures in the inferior's address space to find the list of
1170 threads/LWPs, and those structures may well be corrupted. Note
1171 that once thread_db is loaded, we'll still use it to list threads
1172 and associate pthread info with each LWP. */
1173 linux_proc_attach_tgid_threads (pid, attach_proc_task_lwp_callback);
1175 /* GDB will shortly read the xml target description for this
1176 process, to figure out the process' architecture. But the target
1177 description is only filled in when the first process/thread in
1178 the thread group reports its initial PTRACE_ATTACH SIGSTOP. Do
1179 that now, otherwise, if GDB is fast enough, it could read the
1180 target description _before_ that initial stop. */
1183 struct lwp_info *lwp;
1185 ptid_t pid_ptid = pid_to_ptid (pid);
1187 lwpid = linux_wait_for_event_filtered (pid_ptid, pid_ptid,
1189 gdb_assert (lwpid > 0);
1191 lwp = find_lwp_pid (pid_to_ptid (lwpid));
1193 if (!WIFSTOPPED (wstat) || WSTOPSIG (wstat) != SIGSTOP)
1195 lwp->status_pending_p = 1;
1196 lwp->status_pending = wstat;
1199 initial_thread->last_resume_kind = resume_continue;
1203 gdb_assert (proc->tdesc != NULL);
1216 second_thread_of_pid_p (struct inferior_list_entry *entry, void *args)
1218 struct counter *counter = (struct counter *) args;
1220 if (ptid_get_pid (entry->id) == counter->pid)
1222 if (++counter->count > 1)
1230 last_thread_of_process_p (int pid)
1232 struct counter counter = { pid , 0 };
1234 return (find_inferior (&all_threads,
1235 second_thread_of_pid_p, &counter) == NULL);
1241 linux_kill_one_lwp (struct lwp_info *lwp)
1243 struct thread_info *thr = get_lwp_thread (lwp);
1244 int pid = lwpid_of (thr);
1246 /* PTRACE_KILL is unreliable. After stepping into a signal handler,
1247 there is no signal context, and ptrace(PTRACE_KILL) (or
1248 ptrace(PTRACE_CONT, SIGKILL), pretty much the same) acts like
1249 ptrace(CONT, pid, 0,0) and just resumes the tracee. A better
1250 alternative is to kill with SIGKILL. We only need one SIGKILL
1251 per process, not one for each thread. But since we still support
1252 support debugging programs using raw clone without CLONE_THREAD,
1253 we send one for each thread. For years, we used PTRACE_KILL
1254 only, so we're being a bit paranoid about some old kernels where
1255 PTRACE_KILL might work better (dubious if there are any such, but
1256 that's why it's paranoia), so we try SIGKILL first, PTRACE_KILL
1257 second, and so we're fine everywhere. */
1260 kill_lwp (pid, SIGKILL);
1263 int save_errno = errno;
1265 debug_printf ("LKL: kill_lwp (SIGKILL) %s, 0, 0 (%s)\n",
1266 target_pid_to_str (ptid_of (thr)),
1267 save_errno ? strerror (save_errno) : "OK");
1271 ptrace (PTRACE_KILL, pid, (PTRACE_TYPE_ARG3) 0, (PTRACE_TYPE_ARG4) 0);
1274 int save_errno = errno;
1276 debug_printf ("LKL: PTRACE_KILL %s, 0, 0 (%s)\n",
1277 target_pid_to_str (ptid_of (thr)),
1278 save_errno ? strerror (save_errno) : "OK");
1282 /* Kill LWP and wait for it to die. */
1285 kill_wait_lwp (struct lwp_info *lwp)
1287 struct thread_info *thr = get_lwp_thread (lwp);
1288 int pid = ptid_get_pid (ptid_of (thr));
1289 int lwpid = ptid_get_lwp (ptid_of (thr));
1294 debug_printf ("kwl: killing lwp %d, for pid: %d\n", lwpid, pid);
1298 linux_kill_one_lwp (lwp);
1300 /* Make sure it died. Notes:
1302 - The loop is most likely unnecessary.
1304 - We don't use linux_wait_for_event as that could delete lwps
1305 while we're iterating over them. We're not interested in
1306 any pending status at this point, only in making sure all
1307 wait status on the kernel side are collected until the
1310 - We don't use __WALL here as the __WALL emulation relies on
1311 SIGCHLD, and killing a stopped process doesn't generate
1312 one, nor an exit status.
1314 res = my_waitpid (lwpid, &wstat, 0);
1315 if (res == -1 && errno == ECHILD)
1316 res = my_waitpid (lwpid, &wstat, __WCLONE);
1317 } while (res > 0 && WIFSTOPPED (wstat));
1319 /* Even if it was stopped, the child may have already disappeared.
1320 E.g., if it was killed by SIGKILL. */
1321 if (res < 0 && errno != ECHILD)
1322 perror_with_name ("kill_wait_lwp");
1325 /* Callback for `find_inferior'. Kills an lwp of a given process,
1326 except the leader. */
1329 kill_one_lwp_callback (struct inferior_list_entry *entry, void *args)
1331 struct thread_info *thread = (struct thread_info *) entry;
1332 struct lwp_info *lwp = get_thread_lwp (thread);
1333 int pid = * (int *) args;
1335 if (ptid_get_pid (entry->id) != pid)
1338 /* We avoid killing the first thread here, because of a Linux kernel (at
1339 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
1340 the children get a chance to be reaped, it will remain a zombie
1343 if (lwpid_of (thread) == pid)
1346 debug_printf ("lkop: is last of process %s\n",
1347 target_pid_to_str (entry->id));
1351 kill_wait_lwp (lwp);
1356 linux_kill (int pid)
1358 struct process_info *process;
1359 struct lwp_info *lwp;
1361 process = find_process_pid (pid);
1362 if (process == NULL)
1365 /* If we're killing a running inferior, make sure it is stopped
1366 first, as PTRACE_KILL will not work otherwise. */
1367 stop_all_lwps (0, NULL);
1369 find_inferior (&all_threads, kill_one_lwp_callback , &pid);
1371 /* See the comment in linux_kill_one_lwp. We did not kill the first
1372 thread in the list, so do so now. */
1373 lwp = find_lwp_pid (pid_to_ptid (pid));
1378 debug_printf ("lk_1: cannot find lwp for pid: %d\n",
1382 kill_wait_lwp (lwp);
1384 the_target->mourn (process);
1386 /* Since we presently can only stop all lwps of all processes, we
1387 need to unstop lwps of other processes. */
1388 unstop_all_lwps (0, NULL);
1392 /* Get pending signal of THREAD, for detaching purposes. This is the
1393 signal the thread last stopped for, which we need to deliver to the
1394 thread when detaching, otherwise, it'd be suppressed/lost. */
1397 get_detach_signal (struct thread_info *thread)
1399 enum gdb_signal signo = GDB_SIGNAL_0;
1401 struct lwp_info *lp = get_thread_lwp (thread);
1403 if (lp->status_pending_p)
1404 status = lp->status_pending;
1407 /* If the thread had been suspended by gdbserver, and it stopped
1408 cleanly, then it'll have stopped with SIGSTOP. But we don't
1409 want to deliver that SIGSTOP. */
1410 if (thread->last_status.kind != TARGET_WAITKIND_STOPPED
1411 || thread->last_status.value.sig == GDB_SIGNAL_0)
1414 /* Otherwise, we may need to deliver the signal we
1416 status = lp->last_status;
1419 if (!WIFSTOPPED (status))
1422 debug_printf ("GPS: lwp %s hasn't stopped: no pending signal\n",
1423 target_pid_to_str (ptid_of (thread)));
1427 /* Extended wait statuses aren't real SIGTRAPs. */
1428 if (WSTOPSIG (status) == SIGTRAP && linux_is_extended_waitstatus (status))
1431 debug_printf ("GPS: lwp %s had stopped with extended "
1432 "status: no pending signal\n",
1433 target_pid_to_str (ptid_of (thread)));
1437 signo = gdb_signal_from_host (WSTOPSIG (status));
1439 if (program_signals_p && !program_signals[signo])
1442 debug_printf ("GPS: lwp %s had signal %s, but it is in nopass state\n",
1443 target_pid_to_str (ptid_of (thread)),
1444 gdb_signal_to_string (signo));
1447 else if (!program_signals_p
1448 /* If we have no way to know which signals GDB does not
1449 want to have passed to the program, assume
1450 SIGTRAP/SIGINT, which is GDB's default. */
1451 && (signo == GDB_SIGNAL_TRAP || signo == GDB_SIGNAL_INT))
1454 debug_printf ("GPS: lwp %s had signal %s, "
1455 "but we don't know if we should pass it. "
1456 "Default to not.\n",
1457 target_pid_to_str (ptid_of (thread)),
1458 gdb_signal_to_string (signo));
1464 debug_printf ("GPS: lwp %s has pending signal %s: delivering it.\n",
1465 target_pid_to_str (ptid_of (thread)),
1466 gdb_signal_to_string (signo));
1468 return WSTOPSIG (status);
1473 linux_detach_one_lwp (struct inferior_list_entry *entry, void *args)
1475 struct thread_info *thread = (struct thread_info *) entry;
1476 struct lwp_info *lwp = get_thread_lwp (thread);
1477 int pid = * (int *) args;
1480 if (ptid_get_pid (entry->id) != pid)
1483 /* If there is a pending SIGSTOP, get rid of it. */
1484 if (lwp->stop_expected)
1487 debug_printf ("Sending SIGCONT to %s\n",
1488 target_pid_to_str (ptid_of (thread)));
1490 kill_lwp (lwpid_of (thread), SIGCONT);
1491 lwp->stop_expected = 0;
1494 /* Flush any pending changes to the process's registers. */
1495 regcache_invalidate_thread (thread);
1497 /* Pass on any pending signal for this thread. */
1498 sig = get_detach_signal (thread);
1500 /* Finally, let it resume. */
1501 if (the_low_target.prepare_to_resume != NULL)
1502 the_low_target.prepare_to_resume (lwp);
1503 if (ptrace (PTRACE_DETACH, lwpid_of (thread), (PTRACE_TYPE_ARG3) 0,
1504 (PTRACE_TYPE_ARG4) (long) sig) < 0)
1505 error (_("Can't detach %s: %s"),
1506 target_pid_to_str (ptid_of (thread)),
1514 linux_detach (int pid)
1516 struct process_info *process;
1518 process = find_process_pid (pid);
1519 if (process == NULL)
1522 /* As there's a step over already in progress, let it finish first,
1523 otherwise nesting a stabilize_threads operation on top gets real
1525 complete_ongoing_step_over ();
1527 /* Stop all threads before detaching. First, ptrace requires that
1528 the thread is stopped to sucessfully detach. Second, thread_db
1529 may need to uninstall thread event breakpoints from memory, which
1530 only works with a stopped process anyway. */
1531 stop_all_lwps (0, NULL);
1533 #ifdef USE_THREAD_DB
1534 thread_db_detach (process);
1537 /* Stabilize threads (move out of jump pads). */
1538 stabilize_threads ();
1540 find_inferior (&all_threads, linux_detach_one_lwp, &pid);
1542 the_target->mourn (process);
1544 /* Since we presently can only stop all lwps of all processes, we
1545 need to unstop lwps of other processes. */
1546 unstop_all_lwps (0, NULL);
1550 /* Remove all LWPs that belong to process PROC from the lwp list. */
1553 delete_lwp_callback (struct inferior_list_entry *entry, void *proc)
1555 struct thread_info *thread = (struct thread_info *) entry;
1556 struct lwp_info *lwp = get_thread_lwp (thread);
1557 struct process_info *process = (struct process_info *) proc;
1559 if (pid_of (thread) == pid_of (process))
1566 linux_mourn (struct process_info *process)
1568 struct process_info_private *priv;
1570 #ifdef USE_THREAD_DB
1571 thread_db_mourn (process);
1574 find_inferior (&all_threads, delete_lwp_callback, process);
1576 /* Freeing all private data. */
1577 priv = process->priv;
1578 free (priv->arch_private);
1580 process->priv = NULL;
1582 remove_process (process);
1586 linux_join (int pid)
1591 ret = my_waitpid (pid, &status, 0);
1592 if (WIFEXITED (status) || WIFSIGNALED (status))
1594 } while (ret != -1 || errno != ECHILD);
1597 /* Return nonzero if the given thread is still alive. */
1599 linux_thread_alive (ptid_t ptid)
1601 struct lwp_info *lwp = find_lwp_pid (ptid);
1603 /* We assume we always know if a thread exits. If a whole process
1604 exited but we still haven't been able to report it to GDB, we'll
1605 hold on to the last lwp of the dead process. */
1607 return !lwp_is_marked_dead (lwp);
1612 /* Return 1 if this lwp still has an interesting status pending. If
1613 not (e.g., it had stopped for a breakpoint that is gone), return
1617 thread_still_has_status_pending_p (struct thread_info *thread)
1619 struct lwp_info *lp = get_thread_lwp (thread);
1621 if (!lp->status_pending_p)
1624 if (thread->last_resume_kind != resume_stop
1625 && (lp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT
1626 || lp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT))
1628 struct thread_info *saved_thread;
1632 gdb_assert (lp->last_status != 0);
1636 saved_thread = current_thread;
1637 current_thread = thread;
1639 if (pc != lp->stop_pc)
1642 debug_printf ("PC of %ld changed\n",
1647 #if !USE_SIGTRAP_SIGINFO
1648 else if (lp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT
1649 && !(*the_low_target.breakpoint_at) (pc))
1652 debug_printf ("previous SW breakpoint of %ld gone\n",
1656 else if (lp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT
1657 && !hardware_breakpoint_inserted_here (pc))
1660 debug_printf ("previous HW breakpoint of %ld gone\n",
1666 current_thread = saved_thread;
1671 debug_printf ("discarding pending breakpoint status\n");
1672 lp->status_pending_p = 0;
1680 /* Returns true if LWP is resumed from the client's perspective. */
1683 lwp_resumed (struct lwp_info *lwp)
1685 struct thread_info *thread = get_lwp_thread (lwp);
1687 if (thread->last_resume_kind != resume_stop)
1690 /* Did gdb send us a `vCont;t', but we haven't reported the
1691 corresponding stop to gdb yet? If so, the thread is still
1692 resumed/running from gdb's perspective. */
1693 if (thread->last_resume_kind == resume_stop
1694 && thread->last_status.kind == TARGET_WAITKIND_IGNORE)
1700 /* Return 1 if this lwp has an interesting status pending. */
1702 status_pending_p_callback (struct inferior_list_entry *entry, void *arg)
1704 struct thread_info *thread = (struct thread_info *) entry;
1705 struct lwp_info *lp = get_thread_lwp (thread);
1706 ptid_t ptid = * (ptid_t *) arg;
1708 /* Check if we're only interested in events from a specific process
1709 or a specific LWP. */
1710 if (!ptid_match (ptid_of (thread), ptid))
1713 if (!lwp_resumed (lp))
1716 if (lp->status_pending_p
1717 && !thread_still_has_status_pending_p (thread))
1719 linux_resume_one_lwp (lp, lp->stepping, GDB_SIGNAL_0, NULL);
1723 return lp->status_pending_p;
1727 same_lwp (struct inferior_list_entry *entry, void *data)
1729 ptid_t ptid = *(ptid_t *) data;
1732 if (ptid_get_lwp (ptid) != 0)
1733 lwp = ptid_get_lwp (ptid);
1735 lwp = ptid_get_pid (ptid);
1737 if (ptid_get_lwp (entry->id) == lwp)
1744 find_lwp_pid (ptid_t ptid)
1746 struct inferior_list_entry *thread
1747 = find_inferior (&all_threads, same_lwp, &ptid);
1752 return get_thread_lwp ((struct thread_info *) thread);
1755 /* Return the number of known LWPs in the tgid given by PID. */
1760 struct inferior_list_entry *inf, *tmp;
1763 ALL_INFERIORS (&all_threads, inf, tmp)
1765 if (ptid_get_pid (inf->id) == pid)
1772 /* The arguments passed to iterate_over_lwps. */
1774 struct iterate_over_lwps_args
1776 /* The FILTER argument passed to iterate_over_lwps. */
1779 /* The CALLBACK argument passed to iterate_over_lwps. */
1780 iterate_over_lwps_ftype *callback;
1782 /* The DATA argument passed to iterate_over_lwps. */
1786 /* Callback for find_inferior used by iterate_over_lwps to filter
1787 calls to the callback supplied to that function. Returning a
1788 nonzero value causes find_inferiors to stop iterating and return
1789 the current inferior_list_entry. Returning zero indicates that
1790 find_inferiors should continue iterating. */
1793 iterate_over_lwps_filter (struct inferior_list_entry *entry, void *args_p)
1795 struct iterate_over_lwps_args *args
1796 = (struct iterate_over_lwps_args *) args_p;
1798 if (ptid_match (entry->id, args->filter))
1800 struct thread_info *thr = (struct thread_info *) entry;
1801 struct lwp_info *lwp = get_thread_lwp (thr);
1803 return (*args->callback) (lwp, args->data);
1809 /* See nat/linux-nat.h. */
1812 iterate_over_lwps (ptid_t filter,
1813 iterate_over_lwps_ftype callback,
1816 struct iterate_over_lwps_args args = {filter, callback, data};
1817 struct inferior_list_entry *entry;
1819 entry = find_inferior (&all_threads, iterate_over_lwps_filter, &args);
1823 return get_thread_lwp ((struct thread_info *) entry);
1826 /* Detect zombie thread group leaders, and "exit" them. We can't reap
1827 their exits until all other threads in the group have exited. */
1830 check_zombie_leaders (void)
1832 struct process_info *proc, *tmp;
1834 ALL_PROCESSES (proc, tmp)
1836 pid_t leader_pid = pid_of (proc);
1837 struct lwp_info *leader_lp;
1839 leader_lp = find_lwp_pid (pid_to_ptid (leader_pid));
1842 debug_printf ("leader_pid=%d, leader_lp!=NULL=%d, "
1843 "num_lwps=%d, zombie=%d\n",
1844 leader_pid, leader_lp!= NULL, num_lwps (leader_pid),
1845 linux_proc_pid_is_zombie (leader_pid));
1847 if (leader_lp != NULL && !leader_lp->stopped
1848 /* Check if there are other threads in the group, as we may
1849 have raced with the inferior simply exiting. */
1850 && !last_thread_of_process_p (leader_pid)
1851 && linux_proc_pid_is_zombie (leader_pid))
1853 /* A leader zombie can mean one of two things:
1855 - It exited, and there's an exit status pending
1856 available, or only the leader exited (not the whole
1857 program). In the latter case, we can't waitpid the
1858 leader's exit status until all other threads are gone.
1860 - There are 3 or more threads in the group, and a thread
1861 other than the leader exec'd. On an exec, the Linux
1862 kernel destroys all other threads (except the execing
1863 one) in the thread group, and resets the execing thread's
1864 tid to the tgid. No exit notification is sent for the
1865 execing thread -- from the ptracer's perspective, it
1866 appears as though the execing thread just vanishes.
1867 Until we reap all other threads except the leader and the
1868 execing thread, the leader will be zombie, and the
1869 execing thread will be in `D (disc sleep)'. As soon as
1870 all other threads are reaped, the execing thread changes
1871 it's tid to the tgid, and the previous (zombie) leader
1872 vanishes, giving place to the "new" leader. We could try
1873 distinguishing the exit and exec cases, by waiting once
1874 more, and seeing if something comes out, but it doesn't
1875 sound useful. The previous leader _does_ go away, and
1876 we'll re-add the new one once we see the exec event
1877 (which is just the same as what would happen if the
1878 previous leader did exit voluntarily before some other
1883 "CZL: Thread group leader %d zombie "
1884 "(it exited, or another thread execd).\n",
1887 delete_lwp (leader_lp);
1892 /* Callback for `find_inferior'. Returns the first LWP that is not
1893 stopped. ARG is a PTID filter. */
1896 not_stopped_callback (struct inferior_list_entry *entry, void *arg)
1898 struct thread_info *thr = (struct thread_info *) entry;
1899 struct lwp_info *lwp;
1900 ptid_t filter = *(ptid_t *) arg;
1902 if (!ptid_match (ptid_of (thr), filter))
1905 lwp = get_thread_lwp (thr);
1912 /* Increment LWP's suspend count. */
1915 lwp_suspended_inc (struct lwp_info *lwp)
1919 if (debug_threads && lwp->suspended > 4)
1921 struct thread_info *thread = get_lwp_thread (lwp);
1923 debug_printf ("LWP %ld has a suspiciously high suspend count,"
1924 " suspended=%d\n", lwpid_of (thread), lwp->suspended);
1928 /* Decrement LWP's suspend count. */
1931 lwp_suspended_decr (struct lwp_info *lwp)
1935 if (lwp->suspended < 0)
1937 struct thread_info *thread = get_lwp_thread (lwp);
1939 internal_error (__FILE__, __LINE__,
1940 "unsuspend LWP %ld, suspended=%d\n", lwpid_of (thread),
1945 /* This function should only be called if the LWP got a SIGTRAP.
1947 Handle any tracepoint steps or hits. Return true if a tracepoint
1948 event was handled, 0 otherwise. */
1951 handle_tracepoints (struct lwp_info *lwp)
1953 struct thread_info *tinfo = get_lwp_thread (lwp);
1954 int tpoint_related_event = 0;
1956 gdb_assert (lwp->suspended == 0);
1958 /* If this tracepoint hit causes a tracing stop, we'll immediately
1959 uninsert tracepoints. To do this, we temporarily pause all
1960 threads, unpatch away, and then unpause threads. We need to make
1961 sure the unpausing doesn't resume LWP too. */
1962 lwp_suspended_inc (lwp);
1964 /* And we need to be sure that any all-threads-stopping doesn't try
1965 to move threads out of the jump pads, as it could deadlock the
1966 inferior (LWP could be in the jump pad, maybe even holding the
1969 /* Do any necessary step collect actions. */
1970 tpoint_related_event |= tracepoint_finished_step (tinfo, lwp->stop_pc);
1972 tpoint_related_event |= handle_tracepoint_bkpts (tinfo, lwp->stop_pc);
1974 /* See if we just hit a tracepoint and do its main collect
1976 tpoint_related_event |= tracepoint_was_hit (tinfo, lwp->stop_pc);
1978 lwp_suspended_decr (lwp);
1980 gdb_assert (lwp->suspended == 0);
1981 gdb_assert (!stabilizing_threads || lwp->collecting_fast_tracepoint);
1983 if (tpoint_related_event)
1986 debug_printf ("got a tracepoint event\n");
1993 /* Convenience wrapper. Returns true if LWP is presently collecting a
1997 linux_fast_tracepoint_collecting (struct lwp_info *lwp,
1998 struct fast_tpoint_collect_status *status)
2000 CORE_ADDR thread_area;
2001 struct thread_info *thread = get_lwp_thread (lwp);
2003 if (the_low_target.get_thread_area == NULL)
2006 /* Get the thread area address. This is used to recognize which
2007 thread is which when tracing with the in-process agent library.
2008 We don't read anything from the address, and treat it as opaque;
2009 it's the address itself that we assume is unique per-thread. */
2010 if ((*the_low_target.get_thread_area) (lwpid_of (thread), &thread_area) == -1)
2013 return fast_tracepoint_collecting (thread_area, lwp->stop_pc, status);
2016 /* The reason we resume in the caller, is because we want to be able
2017 to pass lwp->status_pending as WSTAT, and we need to clear
2018 status_pending_p before resuming, otherwise, linux_resume_one_lwp
2019 refuses to resume. */
2022 maybe_move_out_of_jump_pad (struct lwp_info *lwp, int *wstat)
2024 struct thread_info *saved_thread;
2026 saved_thread = current_thread;
2027 current_thread = get_lwp_thread (lwp);
2030 || (WIFSTOPPED (*wstat) && WSTOPSIG (*wstat) != SIGTRAP))
2031 && supports_fast_tracepoints ()
2032 && agent_loaded_p ())
2034 struct fast_tpoint_collect_status status;
2038 debug_printf ("Checking whether LWP %ld needs to move out of the "
2040 lwpid_of (current_thread));
2042 r = linux_fast_tracepoint_collecting (lwp, &status);
2045 || (WSTOPSIG (*wstat) != SIGILL
2046 && WSTOPSIG (*wstat) != SIGFPE
2047 && WSTOPSIG (*wstat) != SIGSEGV
2048 && WSTOPSIG (*wstat) != SIGBUS))
2050 lwp->collecting_fast_tracepoint = r;
2054 if (r == 1 && lwp->exit_jump_pad_bkpt == NULL)
2056 /* Haven't executed the original instruction yet.
2057 Set breakpoint there, and wait till it's hit,
2058 then single-step until exiting the jump pad. */
2059 lwp->exit_jump_pad_bkpt
2060 = set_breakpoint_at (status.adjusted_insn_addr, NULL);
2064 debug_printf ("Checking whether LWP %ld needs to move out of "
2065 "the jump pad...it does\n",
2066 lwpid_of (current_thread));
2067 current_thread = saved_thread;
2074 /* If we get a synchronous signal while collecting, *and*
2075 while executing the (relocated) original instruction,
2076 reset the PC to point at the tpoint address, before
2077 reporting to GDB. Otherwise, it's an IPA lib bug: just
2078 report the signal to GDB, and pray for the best. */
2080 lwp->collecting_fast_tracepoint = 0;
2083 && (status.adjusted_insn_addr <= lwp->stop_pc
2084 && lwp->stop_pc < status.adjusted_insn_addr_end))
2087 struct regcache *regcache;
2089 /* The si_addr on a few signals references the address
2090 of the faulting instruction. Adjust that as
2092 if ((WSTOPSIG (*wstat) == SIGILL
2093 || WSTOPSIG (*wstat) == SIGFPE
2094 || WSTOPSIG (*wstat) == SIGBUS
2095 || WSTOPSIG (*wstat) == SIGSEGV)
2096 && ptrace (PTRACE_GETSIGINFO, lwpid_of (current_thread),
2097 (PTRACE_TYPE_ARG3) 0, &info) == 0
2098 /* Final check just to make sure we don't clobber
2099 the siginfo of non-kernel-sent signals. */
2100 && (uintptr_t) info.si_addr == lwp->stop_pc)
2102 info.si_addr = (void *) (uintptr_t) status.tpoint_addr;
2103 ptrace (PTRACE_SETSIGINFO, lwpid_of (current_thread),
2104 (PTRACE_TYPE_ARG3) 0, &info);
2107 regcache = get_thread_regcache (current_thread, 1);
2108 (*the_low_target.set_pc) (regcache, status.tpoint_addr);
2109 lwp->stop_pc = status.tpoint_addr;
2111 /* Cancel any fast tracepoint lock this thread was
2113 force_unlock_trace_buffer ();
2116 if (lwp->exit_jump_pad_bkpt != NULL)
2119 debug_printf ("Cancelling fast exit-jump-pad: removing bkpt. "
2120 "stopping all threads momentarily.\n");
2122 stop_all_lwps (1, lwp);
2124 delete_breakpoint (lwp->exit_jump_pad_bkpt);
2125 lwp->exit_jump_pad_bkpt = NULL;
2127 unstop_all_lwps (1, lwp);
2129 gdb_assert (lwp->suspended >= 0);
2135 debug_printf ("Checking whether LWP %ld needs to move out of the "
2137 lwpid_of (current_thread));
2139 current_thread = saved_thread;
2143 /* Enqueue one signal in the "signals to report later when out of the
2147 enqueue_one_deferred_signal (struct lwp_info *lwp, int *wstat)
2149 struct pending_signals *p_sig;
2150 struct thread_info *thread = get_lwp_thread (lwp);
2153 debug_printf ("Deferring signal %d for LWP %ld.\n",
2154 WSTOPSIG (*wstat), lwpid_of (thread));
2158 struct pending_signals *sig;
2160 for (sig = lwp->pending_signals_to_report;
2163 debug_printf (" Already queued %d\n",
2166 debug_printf (" (no more currently queued signals)\n");
2169 /* Don't enqueue non-RT signals if they are already in the deferred
2170 queue. (SIGSTOP being the easiest signal to see ending up here
2172 if (WSTOPSIG (*wstat) < __SIGRTMIN)
2174 struct pending_signals *sig;
2176 for (sig = lwp->pending_signals_to_report;
2180 if (sig->signal == WSTOPSIG (*wstat))
2183 debug_printf ("Not requeuing already queued non-RT signal %d"
2192 p_sig = XCNEW (struct pending_signals);
2193 p_sig->prev = lwp->pending_signals_to_report;
2194 p_sig->signal = WSTOPSIG (*wstat);
2196 ptrace (PTRACE_GETSIGINFO, lwpid_of (thread), (PTRACE_TYPE_ARG3) 0,
2199 lwp->pending_signals_to_report = p_sig;
2202 /* Dequeue one signal from the "signals to report later when out of
2203 the jump pad" list. */
2206 dequeue_one_deferred_signal (struct lwp_info *lwp, int *wstat)
2208 struct thread_info *thread = get_lwp_thread (lwp);
2210 if (lwp->pending_signals_to_report != NULL)
2212 struct pending_signals **p_sig;
2214 p_sig = &lwp->pending_signals_to_report;
2215 while ((*p_sig)->prev != NULL)
2216 p_sig = &(*p_sig)->prev;
2218 *wstat = W_STOPCODE ((*p_sig)->signal);
2219 if ((*p_sig)->info.si_signo != 0)
2220 ptrace (PTRACE_SETSIGINFO, lwpid_of (thread), (PTRACE_TYPE_ARG3) 0,
2226 debug_printf ("Reporting deferred signal %d for LWP %ld.\n",
2227 WSTOPSIG (*wstat), lwpid_of (thread));
2231 struct pending_signals *sig;
2233 for (sig = lwp->pending_signals_to_report;
2236 debug_printf (" Still queued %d\n",
2239 debug_printf (" (no more queued signals)\n");
2248 /* Fetch the possibly triggered data watchpoint info and store it in
2251 On some archs, like x86, that use debug registers to set
2252 watchpoints, it's possible that the way to know which watched
2253 address trapped, is to check the register that is used to select
2254 which address to watch. Problem is, between setting the watchpoint
2255 and reading back which data address trapped, the user may change
2256 the set of watchpoints, and, as a consequence, GDB changes the
2257 debug registers in the inferior. To avoid reading back a stale
2258 stopped-data-address when that happens, we cache in LP the fact
2259 that a watchpoint trapped, and the corresponding data address, as
2260 soon as we see CHILD stop with a SIGTRAP. If GDB changes the debug
2261 registers meanwhile, we have the cached data we can rely on. */
2264 check_stopped_by_watchpoint (struct lwp_info *child)
2266 if (the_low_target.stopped_by_watchpoint != NULL)
2268 struct thread_info *saved_thread;
2270 saved_thread = current_thread;
2271 current_thread = get_lwp_thread (child);
2273 if (the_low_target.stopped_by_watchpoint ())
2275 child->stop_reason = TARGET_STOPPED_BY_WATCHPOINT;
2277 if (the_low_target.stopped_data_address != NULL)
2278 child->stopped_data_address
2279 = the_low_target.stopped_data_address ();
2281 child->stopped_data_address = 0;
2284 current_thread = saved_thread;
2287 return child->stop_reason == TARGET_STOPPED_BY_WATCHPOINT;
2290 /* Return the ptrace options that we want to try to enable. */
2293 linux_low_ptrace_options (int attached)
2298 options |= PTRACE_O_EXITKILL;
2300 if (report_fork_events)
2301 options |= PTRACE_O_TRACEFORK;
2303 if (report_vfork_events)
2304 options |= (PTRACE_O_TRACEVFORK | PTRACE_O_TRACEVFORKDONE);
2306 if (report_exec_events)
2307 options |= PTRACE_O_TRACEEXEC;
2309 options |= PTRACE_O_TRACESYSGOOD;
2314 /* Do low-level handling of the event, and check if we should go on
2315 and pass it to caller code. Return the affected lwp if we are, or
2318 static struct lwp_info *
2319 linux_low_filter_event (int lwpid, int wstat)
2321 struct lwp_info *child;
2322 struct thread_info *thread;
2323 int have_stop_pc = 0;
2325 child = find_lwp_pid (pid_to_ptid (lwpid));
2327 /* Check for stop events reported by a process we didn't already
2328 know about - anything not already in our LWP list.
2330 If we're expecting to receive stopped processes after
2331 fork, vfork, and clone events, then we'll just add the
2332 new one to our list and go back to waiting for the event
2333 to be reported - the stopped process might be returned
2334 from waitpid before or after the event is.
2336 But note the case of a non-leader thread exec'ing after the
2337 leader having exited, and gone from our lists (because
2338 check_zombie_leaders deleted it). The non-leader thread
2339 changes its tid to the tgid. */
2341 if (WIFSTOPPED (wstat) && child == NULL && WSTOPSIG (wstat) == SIGTRAP
2342 && linux_ptrace_get_extended_event (wstat) == PTRACE_EVENT_EXEC)
2346 /* A multi-thread exec after we had seen the leader exiting. */
2349 debug_printf ("LLW: Re-adding thread group leader LWP %d"
2350 "after exec.\n", lwpid);
2353 child_ptid = ptid_build (lwpid, lwpid, 0);
2354 child = add_lwp (child_ptid);
2356 current_thread = child->thread;
2359 /* If we didn't find a process, one of two things presumably happened:
2360 - A process we started and then detached from has exited. Ignore it.
2361 - A process we are controlling has forked and the new child's stop
2362 was reported to us by the kernel. Save its PID. */
2363 if (child == NULL && WIFSTOPPED (wstat))
2365 add_to_pid_list (&stopped_pids, lwpid, wstat);
2368 else if (child == NULL)
2371 thread = get_lwp_thread (child);
2375 child->last_status = wstat;
2377 /* Check if the thread has exited. */
2378 if ((WIFEXITED (wstat) || WIFSIGNALED (wstat)))
2381 debug_printf ("LLFE: %d exited.\n", lwpid);
2383 if (finish_step_over (child))
2385 /* Unsuspend all other LWPs, and set them back running again. */
2386 unsuspend_all_lwps (child);
2389 /* If there is at least one more LWP, then the exit signal was
2390 not the end of the debugged application and should be
2391 ignored, unless GDB wants to hear about thread exits. */
2392 if (report_thread_events
2393 || last_thread_of_process_p (pid_of (thread)))
2395 /* Since events are serialized to GDB core, and we can't
2396 report this one right now. Leave the status pending for
2397 the next time we're able to report it. */
2398 mark_lwp_dead (child, wstat);
2408 gdb_assert (WIFSTOPPED (wstat));
2410 if (WIFSTOPPED (wstat))
2412 struct process_info *proc;
2414 /* Architecture-specific setup after inferior is running. */
2415 proc = find_process_pid (pid_of (thread));
2416 if (proc->tdesc == NULL)
2420 /* This needs to happen after we have attached to the
2421 inferior and it is stopped for the first time, but
2422 before we access any inferior registers. */
2423 linux_arch_setup_thread (thread);
2427 /* The process is started, but GDBserver will do
2428 architecture-specific setup after the program stops at
2429 the first instruction. */
2430 child->status_pending_p = 1;
2431 child->status_pending = wstat;
2437 if (WIFSTOPPED (wstat) && child->must_set_ptrace_flags)
2439 struct process_info *proc = find_process_pid (pid_of (thread));
2440 int options = linux_low_ptrace_options (proc->attached);
2442 linux_enable_event_reporting (lwpid, options);
2443 child->must_set_ptrace_flags = 0;
2446 /* Always update syscall_state, even if it will be filtered later. */
2447 if (WIFSTOPPED (wstat) && WSTOPSIG (wstat) == SYSCALL_SIGTRAP)
2449 child->syscall_state
2450 = (child->syscall_state == TARGET_WAITKIND_SYSCALL_ENTRY
2451 ? TARGET_WAITKIND_SYSCALL_RETURN
2452 : TARGET_WAITKIND_SYSCALL_ENTRY);
2456 /* Almost all other ptrace-stops are known to be outside of system
2457 calls, with further exceptions in handle_extended_wait. */
2458 child->syscall_state = TARGET_WAITKIND_IGNORE;
2461 /* Be careful to not overwrite stop_pc until save_stop_reason is
2463 if (WIFSTOPPED (wstat) && WSTOPSIG (wstat) == SIGTRAP
2464 && linux_is_extended_waitstatus (wstat))
2466 child->stop_pc = get_pc (child);
2467 if (handle_extended_wait (&child, wstat))
2469 /* The event has been handled, so just return without
2475 if (linux_wstatus_maybe_breakpoint (wstat))
2477 if (save_stop_reason (child))
2482 child->stop_pc = get_pc (child);
2484 if (WIFSTOPPED (wstat) && WSTOPSIG (wstat) == SIGSTOP
2485 && child->stop_expected)
2488 debug_printf ("Expected stop.\n");
2489 child->stop_expected = 0;
2491 if (thread->last_resume_kind == resume_stop)
2493 /* We want to report the stop to the core. Treat the
2494 SIGSTOP as a normal event. */
2496 debug_printf ("LLW: resume_stop SIGSTOP caught for %s.\n",
2497 target_pid_to_str (ptid_of (thread)));
2499 else if (stopping_threads != NOT_STOPPING_THREADS)
2501 /* Stopping threads. We don't want this SIGSTOP to end up
2504 debug_printf ("LLW: SIGSTOP caught for %s "
2505 "while stopping threads.\n",
2506 target_pid_to_str (ptid_of (thread)));
2511 /* This is a delayed SIGSTOP. Filter out the event. */
2513 debug_printf ("LLW: %s %s, 0, 0 (discard delayed SIGSTOP)\n",
2514 child->stepping ? "step" : "continue",
2515 target_pid_to_str (ptid_of (thread)));
2517 linux_resume_one_lwp (child, child->stepping, 0, NULL);
2522 child->status_pending_p = 1;
2523 child->status_pending = wstat;
2527 /* Return true if THREAD is doing hardware single step. */
2530 maybe_hw_step (struct thread_info *thread)
2532 if (can_hardware_single_step ())
2536 struct process_info *proc = get_thread_process (thread);
2538 /* GDBserver must insert reinsert breakpoint for software
2540 gdb_assert (has_reinsert_breakpoints (proc));
2545 /* Resume LWPs that are currently stopped without any pending status
2546 to report, but are resumed from the core's perspective. */
2549 resume_stopped_resumed_lwps (struct inferior_list_entry *entry)
2551 struct thread_info *thread = (struct thread_info *) entry;
2552 struct lwp_info *lp = get_thread_lwp (thread);
2556 && !lp->status_pending_p
2557 && thread->last_status.kind == TARGET_WAITKIND_IGNORE)
2559 int step = thread->last_resume_kind == resume_step;
2562 debug_printf ("RSRL: resuming stopped-resumed LWP %s at %s: step=%d\n",
2563 target_pid_to_str (ptid_of (thread)),
2564 paddress (lp->stop_pc),
2567 linux_resume_one_lwp (lp, step, GDB_SIGNAL_0, NULL);
2571 /* Wait for an event from child(ren) WAIT_PTID, and return any that
2572 match FILTER_PTID (leaving others pending). The PTIDs can be:
2573 minus_one_ptid, to specify any child; a pid PTID, specifying all
2574 lwps of a thread group; or a PTID representing a single lwp. Store
2575 the stop status through the status pointer WSTAT. OPTIONS is
2576 passed to the waitpid call. Return 0 if no event was found and
2577 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
2578 was found. Return the PID of the stopped child otherwise. */
2581 linux_wait_for_event_filtered (ptid_t wait_ptid, ptid_t filter_ptid,
2582 int *wstatp, int options)
2584 struct thread_info *event_thread;
2585 struct lwp_info *event_child, *requested_child;
2586 sigset_t block_mask, prev_mask;
2589 /* N.B. event_thread points to the thread_info struct that contains
2590 event_child. Keep them in sync. */
2591 event_thread = NULL;
2593 requested_child = NULL;
2595 /* Check for a lwp with a pending status. */
2597 if (ptid_equal (filter_ptid, minus_one_ptid) || ptid_is_pid (filter_ptid))
2599 event_thread = (struct thread_info *)
2600 find_inferior (&all_threads, status_pending_p_callback, &filter_ptid);
2601 if (event_thread != NULL)
2602 event_child = get_thread_lwp (event_thread);
2603 if (debug_threads && event_thread)
2604 debug_printf ("Got a pending child %ld\n", lwpid_of (event_thread));
2606 else if (!ptid_equal (filter_ptid, null_ptid))
2608 requested_child = find_lwp_pid (filter_ptid);
2610 if (stopping_threads == NOT_STOPPING_THREADS
2611 && requested_child->status_pending_p
2612 && requested_child->collecting_fast_tracepoint)
2614 enqueue_one_deferred_signal (requested_child,
2615 &requested_child->status_pending);
2616 requested_child->status_pending_p = 0;
2617 requested_child->status_pending = 0;
2618 linux_resume_one_lwp (requested_child, 0, 0, NULL);
2621 if (requested_child->suspended
2622 && requested_child->status_pending_p)
2624 internal_error (__FILE__, __LINE__,
2625 "requesting an event out of a"
2626 " suspended child?");
2629 if (requested_child->status_pending_p)
2631 event_child = requested_child;
2632 event_thread = get_lwp_thread (event_child);
2636 if (event_child != NULL)
2639 debug_printf ("Got an event from pending child %ld (%04x)\n",
2640 lwpid_of (event_thread), event_child->status_pending);
2641 *wstatp = event_child->status_pending;
2642 event_child->status_pending_p = 0;
2643 event_child->status_pending = 0;
2644 current_thread = event_thread;
2645 return lwpid_of (event_thread);
2648 /* But if we don't find a pending event, we'll have to wait.
2650 We only enter this loop if no process has a pending wait status.
2651 Thus any action taken in response to a wait status inside this
2652 loop is responding as soon as we detect the status, not after any
2655 /* Make sure SIGCHLD is blocked until the sigsuspend below. Block
2656 all signals while here. */
2657 sigfillset (&block_mask);
2658 sigprocmask (SIG_BLOCK, &block_mask, &prev_mask);
2660 /* Always pull all events out of the kernel. We'll randomly select
2661 an event LWP out of all that have events, to prevent
2663 while (event_child == NULL)
2667 /* Always use -1 and WNOHANG, due to couple of a kernel/ptrace
2670 - If the thread group leader exits while other threads in the
2671 thread group still exist, waitpid(TGID, ...) hangs. That
2672 waitpid won't return an exit status until the other threads
2673 in the group are reaped.
2675 - When a non-leader thread execs, that thread just vanishes
2676 without reporting an exit (so we'd hang if we waited for it
2677 explicitly in that case). The exec event is reported to
2680 ret = my_waitpid (-1, wstatp, options | WNOHANG);
2683 debug_printf ("LWFE: waitpid(-1, ...) returned %d, %s\n",
2684 ret, errno ? strerror (errno) : "ERRNO-OK");
2690 debug_printf ("LLW: waitpid %ld received %s\n",
2691 (long) ret, status_to_str (*wstatp));
2694 /* Filter all events. IOW, leave all events pending. We'll
2695 randomly select an event LWP out of all that have events
2697 linux_low_filter_event (ret, *wstatp);
2698 /* Retry until nothing comes out of waitpid. A single
2699 SIGCHLD can indicate more than one child stopped. */
2703 /* Now that we've pulled all events out of the kernel, resume
2704 LWPs that don't have an interesting event to report. */
2705 if (stopping_threads == NOT_STOPPING_THREADS)
2706 for_each_inferior (&all_threads, resume_stopped_resumed_lwps);
2708 /* ... and find an LWP with a status to report to the core, if
2710 event_thread = (struct thread_info *)
2711 find_inferior (&all_threads, status_pending_p_callback, &filter_ptid);
2712 if (event_thread != NULL)
2714 event_child = get_thread_lwp (event_thread);
2715 *wstatp = event_child->status_pending;
2716 event_child->status_pending_p = 0;
2717 event_child->status_pending = 0;
2721 /* Check for zombie thread group leaders. Those can't be reaped
2722 until all other threads in the thread group are. */
2723 check_zombie_leaders ();
2725 /* If there are no resumed children left in the set of LWPs we
2726 want to wait for, bail. We can't just block in
2727 waitpid/sigsuspend, because lwps might have been left stopped
2728 in trace-stop state, and we'd be stuck forever waiting for
2729 their status to change (which would only happen if we resumed
2730 them). Even if WNOHANG is set, this return code is preferred
2731 over 0 (below), as it is more detailed. */
2732 if ((find_inferior (&all_threads,
2733 not_stopped_callback,
2734 &wait_ptid) == NULL))
2737 debug_printf ("LLW: exit (no unwaited-for LWP)\n");
2738 sigprocmask (SIG_SETMASK, &prev_mask, NULL);
2742 /* No interesting event to report to the caller. */
2743 if ((options & WNOHANG))
2746 debug_printf ("WNOHANG set, no event found\n");
2748 sigprocmask (SIG_SETMASK, &prev_mask, NULL);
2752 /* Block until we get an event reported with SIGCHLD. */
2754 debug_printf ("sigsuspend'ing\n");
2756 sigsuspend (&prev_mask);
2757 sigprocmask (SIG_SETMASK, &prev_mask, NULL);
2761 sigprocmask (SIG_SETMASK, &prev_mask, NULL);
2763 current_thread = event_thread;
2765 return lwpid_of (event_thread);
2768 /* Wait for an event from child(ren) PTID. PTIDs can be:
2769 minus_one_ptid, to specify any child; a pid PTID, specifying all
2770 lwps of a thread group; or a PTID representing a single lwp. Store
2771 the stop status through the status pointer WSTAT. OPTIONS is
2772 passed to the waitpid call. Return 0 if no event was found and
2773 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
2774 was found. Return the PID of the stopped child otherwise. */
2777 linux_wait_for_event (ptid_t ptid, int *wstatp, int options)
2779 return linux_wait_for_event_filtered (ptid, ptid, wstatp, options);
2782 /* Count the LWP's that have had events. */
2785 count_events_callback (struct inferior_list_entry *entry, void *data)
2787 struct thread_info *thread = (struct thread_info *) entry;
2788 struct lwp_info *lp = get_thread_lwp (thread);
2789 int *count = (int *) data;
2791 gdb_assert (count != NULL);
2793 /* Count only resumed LWPs that have an event pending. */
2794 if (thread->last_status.kind == TARGET_WAITKIND_IGNORE
2795 && lp->status_pending_p)
2801 /* Select the LWP (if any) that is currently being single-stepped. */
2804 select_singlestep_lwp_callback (struct inferior_list_entry *entry, void *data)
2806 struct thread_info *thread = (struct thread_info *) entry;
2807 struct lwp_info *lp = get_thread_lwp (thread);
2809 if (thread->last_status.kind == TARGET_WAITKIND_IGNORE
2810 && thread->last_resume_kind == resume_step
2811 && lp->status_pending_p)
2817 /* Select the Nth LWP that has had an event. */
2820 select_event_lwp_callback (struct inferior_list_entry *entry, void *data)
2822 struct thread_info *thread = (struct thread_info *) entry;
2823 struct lwp_info *lp = get_thread_lwp (thread);
2824 int *selector = (int *) data;
2826 gdb_assert (selector != NULL);
2828 /* Select only resumed LWPs that have an event pending. */
2829 if (thread->last_status.kind == TARGET_WAITKIND_IGNORE
2830 && lp->status_pending_p)
2831 if ((*selector)-- == 0)
2837 /* Select one LWP out of those that have events pending. */
2840 select_event_lwp (struct lwp_info **orig_lp)
2843 int random_selector;
2844 struct thread_info *event_thread = NULL;
2846 /* In all-stop, give preference to the LWP that is being
2847 single-stepped. There will be at most one, and it's the LWP that
2848 the core is most interested in. If we didn't do this, then we'd
2849 have to handle pending step SIGTRAPs somehow in case the core
2850 later continues the previously-stepped thread, otherwise we'd
2851 report the pending SIGTRAP, and the core, not having stepped the
2852 thread, wouldn't understand what the trap was for, and therefore
2853 would report it to the user as a random signal. */
2857 = (struct thread_info *) find_inferior (&all_threads,
2858 select_singlestep_lwp_callback,
2860 if (event_thread != NULL)
2863 debug_printf ("SEL: Select single-step %s\n",
2864 target_pid_to_str (ptid_of (event_thread)));
2867 if (event_thread == NULL)
2869 /* No single-stepping LWP. Select one at random, out of those
2870 which have had events. */
2872 /* First see how many events we have. */
2873 find_inferior (&all_threads, count_events_callback, &num_events);
2874 gdb_assert (num_events > 0);
2876 /* Now randomly pick a LWP out of those that have had
2878 random_selector = (int)
2879 ((num_events * (double) rand ()) / (RAND_MAX + 1.0));
2881 if (debug_threads && num_events > 1)
2882 debug_printf ("SEL: Found %d SIGTRAP events, selecting #%d\n",
2883 num_events, random_selector);
2886 = (struct thread_info *) find_inferior (&all_threads,
2887 select_event_lwp_callback,
2891 if (event_thread != NULL)
2893 struct lwp_info *event_lp = get_thread_lwp (event_thread);
2895 /* Switch the event LWP. */
2896 *orig_lp = event_lp;
2900 /* Decrement the suspend count of an LWP. */
2903 unsuspend_one_lwp (struct inferior_list_entry *entry, void *except)
2905 struct thread_info *thread = (struct thread_info *) entry;
2906 struct lwp_info *lwp = get_thread_lwp (thread);
2908 /* Ignore EXCEPT. */
2912 lwp_suspended_decr (lwp);
2916 /* Decrement the suspend count of all LWPs, except EXCEPT, if non
2920 unsuspend_all_lwps (struct lwp_info *except)
2922 find_inferior (&all_threads, unsuspend_one_lwp, except);
2925 static void move_out_of_jump_pad_callback (struct inferior_list_entry *entry);
2926 static int stuck_in_jump_pad_callback (struct inferior_list_entry *entry,
2928 static int lwp_running (struct inferior_list_entry *entry, void *data);
2929 static ptid_t linux_wait_1 (ptid_t ptid,
2930 struct target_waitstatus *ourstatus,
2931 int target_options);
2933 /* Stabilize threads (move out of jump pads).
2935 If a thread is midway collecting a fast tracepoint, we need to
2936 finish the collection and move it out of the jump pad before
2937 reporting the signal.
2939 This avoids recursion while collecting (when a signal arrives
2940 midway, and the signal handler itself collects), which would trash
2941 the trace buffer. In case the user set a breakpoint in a signal
2942 handler, this avoids the backtrace showing the jump pad, etc..
2943 Most importantly, there are certain things we can't do safely if
2944 threads are stopped in a jump pad (or in its callee's). For
2947 - starting a new trace run. A thread still collecting the
2948 previous run, could trash the trace buffer when resumed. The trace
2949 buffer control structures would have been reset but the thread had
2950 no way to tell. The thread could even midway memcpy'ing to the
2951 buffer, which would mean that when resumed, it would clobber the
2952 trace buffer that had been set for a new run.
2954 - we can't rewrite/reuse the jump pads for new tracepoints
2955 safely. Say you do tstart while a thread is stopped midway while
2956 collecting. When the thread is later resumed, it finishes the
2957 collection, and returns to the jump pad, to execute the original
2958 instruction that was under the tracepoint jump at the time the
2959 older run had been started. If the jump pad had been rewritten
2960 since for something else in the new run, the thread would now
2961 execute the wrong / random instructions. */
2964 linux_stabilize_threads (void)
2966 struct thread_info *saved_thread;
2967 struct thread_info *thread_stuck;
2970 = (struct thread_info *) find_inferior (&all_threads,
2971 stuck_in_jump_pad_callback,
2973 if (thread_stuck != NULL)
2976 debug_printf ("can't stabilize, LWP %ld is stuck in jump pad\n",
2977 lwpid_of (thread_stuck));
2981 saved_thread = current_thread;
2983 stabilizing_threads = 1;
2986 for_each_inferior (&all_threads, move_out_of_jump_pad_callback);
2988 /* Loop until all are stopped out of the jump pads. */
2989 while (find_inferior (&all_threads, lwp_running, NULL) != NULL)
2991 struct target_waitstatus ourstatus;
2992 struct lwp_info *lwp;
2995 /* Note that we go through the full wait even loop. While
2996 moving threads out of jump pad, we need to be able to step
2997 over internal breakpoints and such. */
2998 linux_wait_1 (minus_one_ptid, &ourstatus, 0);
3000 if (ourstatus.kind == TARGET_WAITKIND_STOPPED)
3002 lwp = get_thread_lwp (current_thread);
3005 lwp_suspended_inc (lwp);
3007 if (ourstatus.value.sig != GDB_SIGNAL_0
3008 || current_thread->last_resume_kind == resume_stop)
3010 wstat = W_STOPCODE (gdb_signal_to_host (ourstatus.value.sig));
3011 enqueue_one_deferred_signal (lwp, &wstat);
3016 unsuspend_all_lwps (NULL);
3018 stabilizing_threads = 0;
3020 current_thread = saved_thread;
3025 = (struct thread_info *) find_inferior (&all_threads,
3026 stuck_in_jump_pad_callback,
3028 if (thread_stuck != NULL)
3029 debug_printf ("couldn't stabilize, LWP %ld got stuck in jump pad\n",
3030 lwpid_of (thread_stuck));
3034 /* Convenience function that is called when the kernel reports an
3035 event that is not passed out to GDB. */
3038 ignore_event (struct target_waitstatus *ourstatus)
3040 /* If we got an event, there may still be others, as a single
3041 SIGCHLD can indicate more than one child stopped. This forces
3042 another target_wait call. */
3045 ourstatus->kind = TARGET_WAITKIND_IGNORE;
3049 /* Convenience function that is called when the kernel reports an exit
3050 event. This decides whether to report the event to GDB as a
3051 process exit event, a thread exit event, or to suppress the
3055 filter_exit_event (struct lwp_info *event_child,
3056 struct target_waitstatus *ourstatus)
3058 struct thread_info *thread = get_lwp_thread (event_child);
3059 ptid_t ptid = ptid_of (thread);
3061 if (!last_thread_of_process_p (pid_of (thread)))
3063 if (report_thread_events)
3064 ourstatus->kind = TARGET_WAITKIND_THREAD_EXITED;
3066 ourstatus->kind = TARGET_WAITKIND_IGNORE;
3068 delete_lwp (event_child);
3073 /* Returns 1 if GDB is interested in any event_child syscalls. */
3076 gdb_catching_syscalls_p (struct lwp_info *event_child)
3078 struct thread_info *thread = get_lwp_thread (event_child);
3079 struct process_info *proc = get_thread_process (thread);
3081 return !VEC_empty (int, proc->syscalls_to_catch);
3084 /* Returns 1 if GDB is interested in the event_child syscall.
3085 Only to be called when stopped reason is SYSCALL_SIGTRAP. */
3088 gdb_catch_this_syscall_p (struct lwp_info *event_child)
3092 struct thread_info *thread = get_lwp_thread (event_child);
3093 struct process_info *proc = get_thread_process (thread);
3095 if (VEC_empty (int, proc->syscalls_to_catch))
3098 if (VEC_index (int, proc->syscalls_to_catch, 0) == ANY_SYSCALL)
3101 get_syscall_trapinfo (event_child, &sysno, &sysret);
3103 VEC_iterate (int, proc->syscalls_to_catch, i, iter);
3111 /* Wait for process, returns status. */
3114 linux_wait_1 (ptid_t ptid,
3115 struct target_waitstatus *ourstatus, int target_options)
3118 struct lwp_info *event_child;
3121 int step_over_finished;
3122 int bp_explains_trap;
3123 int maybe_internal_trap;
3132 debug_printf ("linux_wait_1: [%s]\n", target_pid_to_str (ptid));
3135 /* Translate generic target options into linux options. */
3137 if (target_options & TARGET_WNOHANG)
3140 bp_explains_trap = 0;
3143 ourstatus->kind = TARGET_WAITKIND_IGNORE;
3145 /* Find a resumed LWP, if any. */
3146 if (find_inferior (&all_threads,
3147 status_pending_p_callback,
3148 &minus_one_ptid) != NULL)
3150 else if ((find_inferior (&all_threads,
3151 not_stopped_callback,
3152 &minus_one_ptid) != NULL))
3157 if (ptid_equal (step_over_bkpt, null_ptid))
3158 pid = linux_wait_for_event (ptid, &w, options);
3162 debug_printf ("step_over_bkpt set [%s], doing a blocking wait\n",
3163 target_pid_to_str (step_over_bkpt));
3164 pid = linux_wait_for_event (step_over_bkpt, &w, options & ~WNOHANG);
3167 if (pid == 0 || (pid == -1 && !any_resumed))
3169 gdb_assert (target_options & TARGET_WNOHANG);
3173 debug_printf ("linux_wait_1 ret = null_ptid, "
3174 "TARGET_WAITKIND_IGNORE\n");
3178 ourstatus->kind = TARGET_WAITKIND_IGNORE;
3185 debug_printf ("linux_wait_1 ret = null_ptid, "
3186 "TARGET_WAITKIND_NO_RESUMED\n");
3190 ourstatus->kind = TARGET_WAITKIND_NO_RESUMED;
3194 event_child = get_thread_lwp (current_thread);
3196 /* linux_wait_for_event only returns an exit status for the last
3197 child of a process. Report it. */
3198 if (WIFEXITED (w) || WIFSIGNALED (w))
3202 ourstatus->kind = TARGET_WAITKIND_EXITED;
3203 ourstatus->value.integer = WEXITSTATUS (w);
3207 debug_printf ("linux_wait_1 ret = %s, exited with "
3209 target_pid_to_str (ptid_of (current_thread)),
3216 ourstatus->kind = TARGET_WAITKIND_SIGNALLED;
3217 ourstatus->value.sig = gdb_signal_from_host (WTERMSIG (w));
3221 debug_printf ("linux_wait_1 ret = %s, terminated with "
3223 target_pid_to_str (ptid_of (current_thread)),
3229 if (ourstatus->kind == TARGET_WAITKIND_EXITED)
3230 return filter_exit_event (event_child, ourstatus);
3232 return ptid_of (current_thread);
3235 /* If step-over executes a breakpoint instruction, in the case of a
3236 hardware single step it means a gdb/gdbserver breakpoint had been
3237 planted on top of a permanent breakpoint, in the case of a software
3238 single step it may just mean that gdbserver hit the reinsert breakpoint.
3239 The PC has been adjusted by save_stop_reason to point at
3240 the breakpoint address.
3241 So in the case of the hardware single step advance the PC manually
3242 past the breakpoint and in the case of software single step advance only
3243 if it's not the reinsert_breakpoint we are hitting.
3244 This avoids that a program would keep trapping a permanent breakpoint
3246 if (!ptid_equal (step_over_bkpt, null_ptid)
3247 && event_child->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT
3248 && (event_child->stepping
3249 || !reinsert_breakpoint_inserted_here (event_child->stop_pc)))
3251 int increment_pc = 0;
3252 int breakpoint_kind = 0;
3253 CORE_ADDR stop_pc = event_child->stop_pc;
3256 the_target->breakpoint_kind_from_current_state (&stop_pc);
3257 the_target->sw_breakpoint_from_kind (breakpoint_kind, &increment_pc);
3261 debug_printf ("step-over for %s executed software breakpoint\n",
3262 target_pid_to_str (ptid_of (current_thread)));
3265 if (increment_pc != 0)
3267 struct regcache *regcache
3268 = get_thread_regcache (current_thread, 1);
3270 event_child->stop_pc += increment_pc;
3271 (*the_low_target.set_pc) (regcache, event_child->stop_pc);
3273 if (!(*the_low_target.breakpoint_at) (event_child->stop_pc))
3274 event_child->stop_reason = TARGET_STOPPED_BY_NO_REASON;
3278 /* If this event was not handled before, and is not a SIGTRAP, we
3279 report it. SIGILL and SIGSEGV are also treated as traps in case
3280 a breakpoint is inserted at the current PC. If this target does
3281 not support internal breakpoints at all, we also report the
3282 SIGTRAP without further processing; it's of no concern to us. */
3284 = (supports_breakpoints ()
3285 && (WSTOPSIG (w) == SIGTRAP
3286 || ((WSTOPSIG (w) == SIGILL
3287 || WSTOPSIG (w) == SIGSEGV)
3288 && (*the_low_target.breakpoint_at) (event_child->stop_pc))));
3290 if (maybe_internal_trap)
3292 /* Handle anything that requires bookkeeping before deciding to
3293 report the event or continue waiting. */
3295 /* First check if we can explain the SIGTRAP with an internal
3296 breakpoint, or if we should possibly report the event to GDB.
3297 Do this before anything that may remove or insert a
3299 bp_explains_trap = breakpoint_inserted_here (event_child->stop_pc);
3301 /* We have a SIGTRAP, possibly a step-over dance has just
3302 finished. If so, tweak the state machine accordingly,
3303 reinsert breakpoints and delete any reinsert (software
3304 single-step) breakpoints. */
3305 step_over_finished = finish_step_over (event_child);
3307 /* Now invoke the callbacks of any internal breakpoints there. */
3308 check_breakpoints (event_child->stop_pc);
3310 /* Handle tracepoint data collecting. This may overflow the
3311 trace buffer, and cause a tracing stop, removing
3313 trace_event = handle_tracepoints (event_child);
3315 if (bp_explains_trap)
3318 debug_printf ("Hit a gdbserver breakpoint.\n");
3323 /* We have some other signal, possibly a step-over dance was in
3324 progress, and it should be cancelled too. */
3325 step_over_finished = finish_step_over (event_child);
3328 /* We have all the data we need. Either report the event to GDB, or
3329 resume threads and keep waiting for more. */
3331 /* If we're collecting a fast tracepoint, finish the collection and
3332 move out of the jump pad before delivering a signal. See
3333 linux_stabilize_threads. */
3336 && WSTOPSIG (w) != SIGTRAP
3337 && supports_fast_tracepoints ()
3338 && agent_loaded_p ())
3341 debug_printf ("Got signal %d for LWP %ld. Check if we need "
3342 "to defer or adjust it.\n",
3343 WSTOPSIG (w), lwpid_of (current_thread));
3345 /* Allow debugging the jump pad itself. */
3346 if (current_thread->last_resume_kind != resume_step
3347 && maybe_move_out_of_jump_pad (event_child, &w))
3349 enqueue_one_deferred_signal (event_child, &w);
3352 debug_printf ("Signal %d for LWP %ld deferred (in jump pad)\n",
3353 WSTOPSIG (w), lwpid_of (current_thread));
3355 linux_resume_one_lwp (event_child, 0, 0, NULL);
3357 return ignore_event (ourstatus);
3361 if (event_child->collecting_fast_tracepoint)
3364 debug_printf ("LWP %ld was trying to move out of the jump pad (%d). "
3365 "Check if we're already there.\n",
3366 lwpid_of (current_thread),
3367 event_child->collecting_fast_tracepoint);
3371 event_child->collecting_fast_tracepoint
3372 = linux_fast_tracepoint_collecting (event_child, NULL);
3374 if (event_child->collecting_fast_tracepoint != 1)
3376 /* No longer need this breakpoint. */
3377 if (event_child->exit_jump_pad_bkpt != NULL)
3380 debug_printf ("No longer need exit-jump-pad bkpt; removing it."
3381 "stopping all threads momentarily.\n");
3383 /* Other running threads could hit this breakpoint.
3384 We don't handle moribund locations like GDB does,
3385 instead we always pause all threads when removing
3386 breakpoints, so that any step-over or
3387 decr_pc_after_break adjustment is always taken
3388 care of while the breakpoint is still
3390 stop_all_lwps (1, event_child);
3392 delete_breakpoint (event_child->exit_jump_pad_bkpt);
3393 event_child->exit_jump_pad_bkpt = NULL;
3395 unstop_all_lwps (1, event_child);
3397 gdb_assert (event_child->suspended >= 0);
3401 if (event_child->collecting_fast_tracepoint == 0)
3404 debug_printf ("fast tracepoint finished "
3405 "collecting successfully.\n");
3407 /* We may have a deferred signal to report. */
3408 if (dequeue_one_deferred_signal (event_child, &w))
3411 debug_printf ("dequeued one signal.\n");
3416 debug_printf ("no deferred signals.\n");
3418 if (stabilizing_threads)
3420 ourstatus->kind = TARGET_WAITKIND_STOPPED;
3421 ourstatus->value.sig = GDB_SIGNAL_0;
3425 debug_printf ("linux_wait_1 ret = %s, stopped "
3426 "while stabilizing threads\n",
3427 target_pid_to_str (ptid_of (current_thread)));
3431 return ptid_of (current_thread);
3437 /* Check whether GDB would be interested in this event. */
3439 /* Check if GDB is interested in this syscall. */
3441 && WSTOPSIG (w) == SYSCALL_SIGTRAP
3442 && !gdb_catch_this_syscall_p (event_child))
3446 debug_printf ("Ignored syscall for LWP %ld.\n",
3447 lwpid_of (current_thread));
3450 linux_resume_one_lwp (event_child, event_child->stepping,
3452 return ignore_event (ourstatus);
3455 /* If GDB is not interested in this signal, don't stop other
3456 threads, and don't report it to GDB. Just resume the inferior
3457 right away. We do this for threading-related signals as well as
3458 any that GDB specifically requested we ignore. But never ignore
3459 SIGSTOP if we sent it ourselves, and do not ignore signals when
3460 stepping - they may require special handling to skip the signal
3461 handler. Also never ignore signals that could be caused by a
3464 && current_thread->last_resume_kind != resume_step
3466 #if defined (USE_THREAD_DB) && !defined (__ANDROID__)
3467 (current_process ()->priv->thread_db != NULL
3468 && (WSTOPSIG (w) == __SIGRTMIN
3469 || WSTOPSIG (w) == __SIGRTMIN + 1))
3472 (pass_signals[gdb_signal_from_host (WSTOPSIG (w))]
3473 && !(WSTOPSIG (w) == SIGSTOP
3474 && current_thread->last_resume_kind == resume_stop)
3475 && !linux_wstatus_maybe_breakpoint (w))))
3477 siginfo_t info, *info_p;
3480 debug_printf ("Ignored signal %d for LWP %ld.\n",
3481 WSTOPSIG (w), lwpid_of (current_thread));
3483 if (ptrace (PTRACE_GETSIGINFO, lwpid_of (current_thread),
3484 (PTRACE_TYPE_ARG3) 0, &info) == 0)
3489 if (step_over_finished)
3491 /* We cancelled this thread's step-over above. We still
3492 need to unsuspend all other LWPs, and set them back
3493 running again while the signal handler runs. */
3494 unsuspend_all_lwps (event_child);
3496 /* Enqueue the pending signal info so that proceed_all_lwps
3498 enqueue_pending_signal (event_child, WSTOPSIG (w), info_p);
3500 proceed_all_lwps ();
3504 linux_resume_one_lwp (event_child, event_child->stepping,
3505 WSTOPSIG (w), info_p);
3507 return ignore_event (ourstatus);
3510 /* Note that all addresses are always "out of the step range" when
3511 there's no range to begin with. */
3512 in_step_range = lwp_in_step_range (event_child);
3514 /* If GDB wanted this thread to single step, and the thread is out
3515 of the step range, we always want to report the SIGTRAP, and let
3516 GDB handle it. Watchpoints should always be reported. So should
3517 signals we can't explain. A SIGTRAP we can't explain could be a
3518 GDB breakpoint --- we may or not support Z0 breakpoints. If we
3519 do, we're be able to handle GDB breakpoints on top of internal
3520 breakpoints, by handling the internal breakpoint and still
3521 reporting the event to GDB. If we don't, we're out of luck, GDB
3522 won't see the breakpoint hit. If we see a single-step event but
3523 the thread should be continuing, don't pass the trap to gdb.
3524 That indicates that we had previously finished a single-step but
3525 left the single-step pending -- see
3526 complete_ongoing_step_over. */
3527 report_to_gdb = (!maybe_internal_trap
3528 || (current_thread->last_resume_kind == resume_step
3530 || event_child->stop_reason == TARGET_STOPPED_BY_WATCHPOINT
3532 && !bp_explains_trap
3534 && !step_over_finished
3535 && !(current_thread->last_resume_kind == resume_continue
3536 && event_child->stop_reason == TARGET_STOPPED_BY_SINGLE_STEP))
3537 || (gdb_breakpoint_here (event_child->stop_pc)
3538 && gdb_condition_true_at_breakpoint (event_child->stop_pc)
3539 && gdb_no_commands_at_breakpoint (event_child->stop_pc))
3540 || event_child->waitstatus.kind != TARGET_WAITKIND_IGNORE);
3542 run_breakpoint_commands (event_child->stop_pc);
3544 /* We found no reason GDB would want us to stop. We either hit one
3545 of our own breakpoints, or finished an internal step GDB
3546 shouldn't know about. */
3551 if (bp_explains_trap)
3552 debug_printf ("Hit a gdbserver breakpoint.\n");
3553 if (step_over_finished)
3554 debug_printf ("Step-over finished.\n");
3556 debug_printf ("Tracepoint event.\n");
3557 if (lwp_in_step_range (event_child))
3558 debug_printf ("Range stepping pc 0x%s [0x%s, 0x%s).\n",
3559 paddress (event_child->stop_pc),
3560 paddress (event_child->step_range_start),
3561 paddress (event_child->step_range_end));
3564 /* We're not reporting this breakpoint to GDB, so apply the
3565 decr_pc_after_break adjustment to the inferior's regcache
3568 if (the_low_target.set_pc != NULL)
3570 struct regcache *regcache
3571 = get_thread_regcache (current_thread, 1);
3572 (*the_low_target.set_pc) (regcache, event_child->stop_pc);
3575 /* We may have finished stepping over a breakpoint. If so,
3576 we've stopped and suspended all LWPs momentarily except the
3577 stepping one. This is where we resume them all again. We're
3578 going to keep waiting, so use proceed, which handles stepping
3579 over the next breakpoint. */
3581 debug_printf ("proceeding all threads.\n");
3583 if (step_over_finished)
3584 unsuspend_all_lwps (event_child);
3586 proceed_all_lwps ();
3587 return ignore_event (ourstatus);
3592 if (event_child->waitstatus.kind != TARGET_WAITKIND_IGNORE)
3596 str = target_waitstatus_to_string (&event_child->waitstatus);
3597 debug_printf ("LWP %ld: extended event with waitstatus %s\n",
3598 lwpid_of (get_lwp_thread (event_child)), str);
3601 if (current_thread->last_resume_kind == resume_step)
3603 if (event_child->step_range_start == event_child->step_range_end)
3604 debug_printf ("GDB wanted to single-step, reporting event.\n");
3605 else if (!lwp_in_step_range (event_child))
3606 debug_printf ("Out of step range, reporting event.\n");
3608 if (event_child->stop_reason == TARGET_STOPPED_BY_WATCHPOINT)
3609 debug_printf ("Stopped by watchpoint.\n");
3610 else if (gdb_breakpoint_here (event_child->stop_pc))
3611 debug_printf ("Stopped by GDB breakpoint.\n");
3613 debug_printf ("Hit a non-gdbserver trap event.\n");
3616 /* Alright, we're going to report a stop. */
3618 if (!stabilizing_threads)
3620 /* In all-stop, stop all threads. */
3622 stop_all_lwps (0, NULL);
3624 /* If we're not waiting for a specific LWP, choose an event LWP
3625 from among those that have had events. Giving equal priority
3626 to all LWPs that have had events helps prevent
3628 if (ptid_equal (ptid, minus_one_ptid))
3630 event_child->status_pending_p = 1;
3631 event_child->status_pending = w;
3633 select_event_lwp (&event_child);
3635 /* current_thread and event_child must stay in sync. */
3636 current_thread = get_lwp_thread (event_child);
3638 event_child->status_pending_p = 0;
3639 w = event_child->status_pending;
3642 if (step_over_finished)
3646 /* If we were doing a step-over, all other threads but
3647 the stepping one had been paused in start_step_over,
3648 with their suspend counts incremented. We don't want
3649 to do a full unstop/unpause, because we're in
3650 all-stop mode (so we want threads stopped), but we
3651 still need to unsuspend the other threads, to
3652 decrement their `suspended' count back. */
3653 unsuspend_all_lwps (event_child);
3657 /* If we just finished a step-over, then all threads had
3658 been momentarily paused. In all-stop, that's fine,
3659 we want threads stopped by now anyway. In non-stop,
3660 we need to re-resume threads that GDB wanted to be
3662 unstop_all_lwps (1, event_child);
3666 /* Stabilize threads (move out of jump pads). */
3668 stabilize_threads ();
3672 /* If we just finished a step-over, then all threads had been
3673 momentarily paused. In all-stop, that's fine, we want
3674 threads stopped by now anyway. In non-stop, we need to
3675 re-resume threads that GDB wanted to be running. */
3676 if (step_over_finished)
3677 unstop_all_lwps (1, event_child);
3680 if (event_child->waitstatus.kind != TARGET_WAITKIND_IGNORE)
3682 /* If the reported event is an exit, fork, vfork or exec, let
3684 *ourstatus = event_child->waitstatus;
3685 /* Clear the event lwp's waitstatus since we handled it already. */
3686 event_child->waitstatus.kind = TARGET_WAITKIND_IGNORE;
3689 ourstatus->kind = TARGET_WAITKIND_STOPPED;
3691 /* Now that we've selected our final event LWP, un-adjust its PC if
3692 it was a software breakpoint, and the client doesn't know we can
3693 adjust the breakpoint ourselves. */
3694 if (event_child->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT
3695 && !swbreak_feature)
3697 int decr_pc = the_low_target.decr_pc_after_break;
3701 struct regcache *regcache
3702 = get_thread_regcache (current_thread, 1);
3703 (*the_low_target.set_pc) (regcache, event_child->stop_pc + decr_pc);
3707 if (WSTOPSIG (w) == SYSCALL_SIGTRAP)
3711 get_syscall_trapinfo (event_child,
3712 &ourstatus->value.syscall_number, &sysret);
3713 ourstatus->kind = event_child->syscall_state;
3715 else if (current_thread->last_resume_kind == resume_stop
3716 && WSTOPSIG (w) == SIGSTOP)
3718 /* A thread that has been requested to stop by GDB with vCont;t,
3719 and it stopped cleanly, so report as SIG0. The use of
3720 SIGSTOP is an implementation detail. */
3721 ourstatus->value.sig = GDB_SIGNAL_0;
3723 else if (current_thread->last_resume_kind == resume_stop
3724 && WSTOPSIG (w) != SIGSTOP)
3726 /* A thread that has been requested to stop by GDB with vCont;t,
3727 but, it stopped for other reasons. */
3728 ourstatus->value.sig = gdb_signal_from_host (WSTOPSIG (w));
3730 else if (ourstatus->kind == TARGET_WAITKIND_STOPPED)
3732 ourstatus->value.sig = gdb_signal_from_host (WSTOPSIG (w));
3735 gdb_assert (ptid_equal (step_over_bkpt, null_ptid));
3739 debug_printf ("linux_wait_1 ret = %s, %d, %d\n",
3740 target_pid_to_str (ptid_of (current_thread)),
3741 ourstatus->kind, ourstatus->value.sig);
3745 if (ourstatus->kind == TARGET_WAITKIND_EXITED)
3746 return filter_exit_event (event_child, ourstatus);
3748 return ptid_of (current_thread);
3751 /* Get rid of any pending event in the pipe. */
3753 async_file_flush (void)
3759 ret = read (linux_event_pipe[0], &buf, 1);
3760 while (ret >= 0 || (ret == -1 && errno == EINTR));
3763 /* Put something in the pipe, so the event loop wakes up. */
3765 async_file_mark (void)
3769 async_file_flush ();
3772 ret = write (linux_event_pipe[1], "+", 1);
3773 while (ret == 0 || (ret == -1 && errno == EINTR));
3775 /* Ignore EAGAIN. If the pipe is full, the event loop will already
3776 be awakened anyway. */
3780 linux_wait (ptid_t ptid,
3781 struct target_waitstatus *ourstatus, int target_options)
3785 /* Flush the async file first. */
3786 if (target_is_async_p ())
3787 async_file_flush ();
3791 event_ptid = linux_wait_1 (ptid, ourstatus, target_options);
3793 while ((target_options & TARGET_WNOHANG) == 0
3794 && ptid_equal (event_ptid, null_ptid)
3795 && ourstatus->kind == TARGET_WAITKIND_IGNORE);
3797 /* If at least one stop was reported, there may be more. A single
3798 SIGCHLD can signal more than one child stop. */
3799 if (target_is_async_p ()
3800 && (target_options & TARGET_WNOHANG) != 0
3801 && !ptid_equal (event_ptid, null_ptid))
3807 /* Send a signal to an LWP. */
3810 kill_lwp (unsigned long lwpid, int signo)
3815 ret = syscall (__NR_tkill, lwpid, signo);
3816 if (errno == ENOSYS)
3818 /* If tkill fails, then we are not using nptl threads, a
3819 configuration we no longer support. */
3820 perror_with_name (("tkill"));
3826 linux_stop_lwp (struct lwp_info *lwp)
3832 send_sigstop (struct lwp_info *lwp)
3836 pid = lwpid_of (get_lwp_thread (lwp));
3838 /* If we already have a pending stop signal for this process, don't
3840 if (lwp->stop_expected)
3843 debug_printf ("Have pending sigstop for lwp %d\n", pid);
3849 debug_printf ("Sending sigstop to lwp %d\n", pid);
3851 lwp->stop_expected = 1;
3852 kill_lwp (pid, SIGSTOP);
3856 send_sigstop_callback (struct inferior_list_entry *entry, void *except)
3858 struct thread_info *thread = (struct thread_info *) entry;
3859 struct lwp_info *lwp = get_thread_lwp (thread);
3861 /* Ignore EXCEPT. */
3872 /* Increment the suspend count of an LWP, and stop it, if not stopped
3875 suspend_and_send_sigstop_callback (struct inferior_list_entry *entry,
3878 struct thread_info *thread = (struct thread_info *) entry;
3879 struct lwp_info *lwp = get_thread_lwp (thread);
3881 /* Ignore EXCEPT. */
3885 lwp_suspended_inc (lwp);
3887 return send_sigstop_callback (entry, except);
3891 mark_lwp_dead (struct lwp_info *lwp, int wstat)
3893 /* Store the exit status for later. */
3894 lwp->status_pending_p = 1;
3895 lwp->status_pending = wstat;
3897 /* Store in waitstatus as well, as there's nothing else to process
3899 if (WIFEXITED (wstat))
3901 lwp->waitstatus.kind = TARGET_WAITKIND_EXITED;
3902 lwp->waitstatus.value.integer = WEXITSTATUS (wstat);
3904 else if (WIFSIGNALED (wstat))
3906 lwp->waitstatus.kind = TARGET_WAITKIND_SIGNALLED;
3907 lwp->waitstatus.value.sig = gdb_signal_from_host (WTERMSIG (wstat));
3910 /* Prevent trying to stop it. */
3913 /* No further stops are expected from a dead lwp. */
3914 lwp->stop_expected = 0;
3917 /* Return true if LWP has exited already, and has a pending exit event
3918 to report to GDB. */
3921 lwp_is_marked_dead (struct lwp_info *lwp)
3923 return (lwp->status_pending_p
3924 && (WIFEXITED (lwp->status_pending)
3925 || WIFSIGNALED (lwp->status_pending)));
3928 /* Wait for all children to stop for the SIGSTOPs we just queued. */
3931 wait_for_sigstop (void)
3933 struct thread_info *saved_thread;
3938 saved_thread = current_thread;
3939 if (saved_thread != NULL)
3940 saved_tid = saved_thread->entry.id;
3942 saved_tid = null_ptid; /* avoid bogus unused warning */
3945 debug_printf ("wait_for_sigstop: pulling events\n");
3947 /* Passing NULL_PTID as filter indicates we want all events to be
3948 left pending. Eventually this returns when there are no
3949 unwaited-for children left. */
3950 ret = linux_wait_for_event_filtered (minus_one_ptid, null_ptid,
3952 gdb_assert (ret == -1);
3954 if (saved_thread == NULL || linux_thread_alive (saved_tid))
3955 current_thread = saved_thread;
3959 debug_printf ("Previously current thread died.\n");
3961 /* We can't change the current inferior behind GDB's back,
3962 otherwise, a subsequent command may apply to the wrong
3964 current_thread = NULL;
3968 /* Returns true if LWP ENTRY is stopped in a jump pad, and we can't
3969 move it out, because we need to report the stop event to GDB. For
3970 example, if the user puts a breakpoint in the jump pad, it's
3971 because she wants to debug it. */
3974 stuck_in_jump_pad_callback (struct inferior_list_entry *entry, void *data)
3976 struct thread_info *thread = (struct thread_info *) entry;
3977 struct lwp_info *lwp = get_thread_lwp (thread);
3979 if (lwp->suspended != 0)
3981 internal_error (__FILE__, __LINE__,
3982 "LWP %ld is suspended, suspended=%d\n",
3983 lwpid_of (thread), lwp->suspended);
3985 gdb_assert (lwp->stopped);
3987 /* Allow debugging the jump pad, gdb_collect, etc.. */
3988 return (supports_fast_tracepoints ()
3989 && agent_loaded_p ()
3990 && (gdb_breakpoint_here (lwp->stop_pc)
3991 || lwp->stop_reason == TARGET_STOPPED_BY_WATCHPOINT
3992 || thread->last_resume_kind == resume_step)
3993 && linux_fast_tracepoint_collecting (lwp, NULL));
3997 move_out_of_jump_pad_callback (struct inferior_list_entry *entry)
3999 struct thread_info *thread = (struct thread_info *) entry;
4000 struct thread_info *saved_thread;
4001 struct lwp_info *lwp = get_thread_lwp (thread);
4004 if (lwp->suspended != 0)
4006 internal_error (__FILE__, __LINE__,
4007 "LWP %ld is suspended, suspended=%d\n",
4008 lwpid_of (thread), lwp->suspended);
4010 gdb_assert (lwp->stopped);
4012 /* For gdb_breakpoint_here. */
4013 saved_thread = current_thread;
4014 current_thread = thread;
4016 wstat = lwp->status_pending_p ? &lwp->status_pending : NULL;
4018 /* Allow debugging the jump pad, gdb_collect, etc. */
4019 if (!gdb_breakpoint_here (lwp->stop_pc)
4020 && lwp->stop_reason != TARGET_STOPPED_BY_WATCHPOINT
4021 && thread->last_resume_kind != resume_step
4022 && maybe_move_out_of_jump_pad (lwp, wstat))
4025 debug_printf ("LWP %ld needs stabilizing (in jump pad)\n",
4030 lwp->status_pending_p = 0;
4031 enqueue_one_deferred_signal (lwp, wstat);
4034 debug_printf ("Signal %d for LWP %ld deferred "
4036 WSTOPSIG (*wstat), lwpid_of (thread));
4039 linux_resume_one_lwp (lwp, 0, 0, NULL);
4042 lwp_suspended_inc (lwp);
4044 current_thread = saved_thread;
4048 lwp_running (struct inferior_list_entry *entry, void *data)
4050 struct thread_info *thread = (struct thread_info *) entry;
4051 struct lwp_info *lwp = get_thread_lwp (thread);
4053 if (lwp_is_marked_dead (lwp))
4060 /* Stop all lwps that aren't stopped yet, except EXCEPT, if not NULL.
4061 If SUSPEND, then also increase the suspend count of every LWP,
4065 stop_all_lwps (int suspend, struct lwp_info *except)
4067 /* Should not be called recursively. */
4068 gdb_assert (stopping_threads == NOT_STOPPING_THREADS);
4073 debug_printf ("stop_all_lwps (%s, except=%s)\n",
4074 suspend ? "stop-and-suspend" : "stop",
4076 ? target_pid_to_str (ptid_of (get_lwp_thread (except)))
4080 stopping_threads = (suspend
4081 ? STOPPING_AND_SUSPENDING_THREADS
4082 : STOPPING_THREADS);
4085 find_inferior (&all_threads, suspend_and_send_sigstop_callback, except);
4087 find_inferior (&all_threads, send_sigstop_callback, except);
4088 wait_for_sigstop ();
4089 stopping_threads = NOT_STOPPING_THREADS;
4093 debug_printf ("stop_all_lwps done, setting stopping_threads "
4094 "back to !stopping\n");
4099 /* Enqueue one signal in the chain of signals which need to be
4100 delivered to this process on next resume. */
4103 enqueue_pending_signal (struct lwp_info *lwp, int signal, siginfo_t *info)
4105 struct pending_signals *p_sig = XNEW (struct pending_signals);
4107 p_sig->prev = lwp->pending_signals;
4108 p_sig->signal = signal;
4110 memset (&p_sig->info, 0, sizeof (siginfo_t));
4112 memcpy (&p_sig->info, info, sizeof (siginfo_t));
4113 lwp->pending_signals = p_sig;
4116 /* Install breakpoints for software single stepping. */
4119 install_software_single_step_breakpoints (struct lwp_info *lwp)
4123 struct regcache *regcache = get_thread_regcache (current_thread, 1);
4124 VEC (CORE_ADDR) *next_pcs = NULL;
4125 struct cleanup *old_chain = make_cleanup (VEC_cleanup (CORE_ADDR), &next_pcs);
4127 next_pcs = (*the_low_target.get_next_pcs) (regcache);
4129 for (i = 0; VEC_iterate (CORE_ADDR, next_pcs, i, pc); ++i)
4130 set_reinsert_breakpoint (pc);
4132 do_cleanups (old_chain);
4135 /* Single step via hardware or software single step.
4136 Return 1 if hardware single stepping, 0 if software single stepping
4137 or can't single step. */
4140 single_step (struct lwp_info* lwp)
4144 if (can_hardware_single_step ())
4148 else if (can_software_single_step ())
4150 install_software_single_step_breakpoints (lwp);
4156 debug_printf ("stepping is not implemented on this target");
4162 /* The signal can be delivered to the inferior if we are not trying to
4163 finish a fast tracepoint collect. Since signal can be delivered in
4164 the step-over, the program may go to signal handler and trap again
4165 after return from the signal handler. We can live with the spurious
4169 lwp_signal_can_be_delivered (struct lwp_info *lwp)
4171 return !lwp->collecting_fast_tracepoint;
4174 /* Resume execution of LWP. If STEP is nonzero, single-step it. If
4175 SIGNAL is nonzero, give it that signal. */
4178 linux_resume_one_lwp_throw (struct lwp_info *lwp,
4179 int step, int signal, siginfo_t *info)
4181 struct thread_info *thread = get_lwp_thread (lwp);
4182 struct thread_info *saved_thread;
4183 int fast_tp_collecting;
4185 struct process_info *proc = get_thread_process (thread);
4187 /* Note that target description may not be initialised
4188 (proc->tdesc == NULL) at this point because the program hasn't
4189 stopped at the first instruction yet. It means GDBserver skips
4190 the extra traps from the wrapper program (see option --wrapper).
4191 Code in this function that requires register access should be
4192 guarded by proc->tdesc == NULL or something else. */
4194 if (lwp->stopped == 0)
4197 gdb_assert (lwp->waitstatus.kind == TARGET_WAITKIND_IGNORE);
4199 fast_tp_collecting = lwp->collecting_fast_tracepoint;
4201 gdb_assert (!stabilizing_threads || fast_tp_collecting);
4203 /* Cancel actions that rely on GDB not changing the PC (e.g., the
4204 user used the "jump" command, or "set $pc = foo"). */
4205 if (thread->while_stepping != NULL && lwp->stop_pc != get_pc (lwp))
4207 /* Collecting 'while-stepping' actions doesn't make sense
4209 release_while_stepping_state_list (thread);
4212 /* If we have pending signals or status, and a new signal, enqueue the
4213 signal. Also enqueue the signal if it can't be delivered to the
4214 inferior right now. */
4216 && (lwp->status_pending_p
4217 || lwp->pending_signals != NULL
4218 || !lwp_signal_can_be_delivered (lwp)))
4220 enqueue_pending_signal (lwp, signal, info);
4222 /* Postpone any pending signal. It was enqueued above. */
4226 if (lwp->status_pending_p)
4229 debug_printf ("Not resuming lwp %ld (%s, stop %s);"
4230 " has pending status\n",
4231 lwpid_of (thread), step ? "step" : "continue",
4232 lwp->stop_expected ? "expected" : "not expected");
4236 saved_thread = current_thread;
4237 current_thread = thread;
4239 /* This bit needs some thinking about. If we get a signal that
4240 we must report while a single-step reinsert is still pending,
4241 we often end up resuming the thread. It might be better to
4242 (ew) allow a stack of pending events; then we could be sure that
4243 the reinsert happened right away and not lose any signals.
4245 Making this stack would also shrink the window in which breakpoints are
4246 uninserted (see comment in linux_wait_for_lwp) but not enough for
4247 complete correctness, so it won't solve that problem. It may be
4248 worthwhile just to solve this one, however. */
4249 if (lwp->bp_reinsert != 0)
4252 debug_printf (" pending reinsert at 0x%s\n",
4253 paddress (lwp->bp_reinsert));
4255 if (can_hardware_single_step ())
4257 if (fast_tp_collecting == 0)
4260 fprintf (stderr, "BAD - reinserting but not stepping.\n");
4262 fprintf (stderr, "BAD - reinserting and suspended(%d).\n",
4267 step = maybe_hw_step (thread);
4271 /* If the thread isn't doing step-over, there shouldn't be any
4272 reinsert breakpoints. */
4273 gdb_assert (!has_reinsert_breakpoints (proc));
4276 if (fast_tp_collecting == 1)
4279 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
4280 " (exit-jump-pad-bkpt)\n",
4283 else if (fast_tp_collecting == 2)
4286 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
4287 " single-stepping\n",
4290 if (can_hardware_single_step ())
4294 internal_error (__FILE__, __LINE__,
4295 "moving out of jump pad single-stepping"
4296 " not implemented on this target");
4300 /* If we have while-stepping actions in this thread set it stepping.
4301 If we have a signal to deliver, it may or may not be set to
4302 SIG_IGN, we don't know. Assume so, and allow collecting
4303 while-stepping into a signal handler. A possible smart thing to
4304 do would be to set an internal breakpoint at the signal return
4305 address, continue, and carry on catching this while-stepping
4306 action only when that breakpoint is hit. A future
4308 if (thread->while_stepping != NULL)
4311 debug_printf ("lwp %ld has a while-stepping action -> forcing step.\n",
4314 step = single_step (lwp);
4317 if (proc->tdesc != NULL && the_low_target.get_pc != NULL)
4319 struct regcache *regcache = get_thread_regcache (current_thread, 1);
4321 lwp->stop_pc = (*the_low_target.get_pc) (regcache);
4325 debug_printf (" %s from pc 0x%lx\n", step ? "step" : "continue",
4326 (long) lwp->stop_pc);
4330 /* If we have pending signals, consume one if it can be delivered to
4332 if (lwp->pending_signals != NULL && lwp_signal_can_be_delivered (lwp))
4334 struct pending_signals **p_sig;
4336 p_sig = &lwp->pending_signals;
4337 while ((*p_sig)->prev != NULL)
4338 p_sig = &(*p_sig)->prev;
4340 signal = (*p_sig)->signal;
4341 if ((*p_sig)->info.si_signo != 0)
4342 ptrace (PTRACE_SETSIGINFO, lwpid_of (thread), (PTRACE_TYPE_ARG3) 0,
4350 debug_printf ("Resuming lwp %ld (%s, signal %d, stop %s)\n",
4351 lwpid_of (thread), step ? "step" : "continue", signal,
4352 lwp->stop_expected ? "expected" : "not expected");
4354 if (the_low_target.prepare_to_resume != NULL)
4355 the_low_target.prepare_to_resume (lwp);
4357 regcache_invalidate_thread (thread);
4359 lwp->stepping = step;
4361 ptrace_request = PTRACE_SINGLESTEP;
4362 else if (gdb_catching_syscalls_p (lwp))
4363 ptrace_request = PTRACE_SYSCALL;
4365 ptrace_request = PTRACE_CONT;
4366 ptrace (ptrace_request,
4368 (PTRACE_TYPE_ARG3) 0,
4369 /* Coerce to a uintptr_t first to avoid potential gcc warning
4370 of coercing an 8 byte integer to a 4 byte pointer. */
4371 (PTRACE_TYPE_ARG4) (uintptr_t) signal);
4373 current_thread = saved_thread;
4375 perror_with_name ("resuming thread");
4377 /* Successfully resumed. Clear state that no longer makes sense,
4378 and mark the LWP as running. Must not do this before resuming
4379 otherwise if that fails other code will be confused. E.g., we'd
4380 later try to stop the LWP and hang forever waiting for a stop
4381 status. Note that we must not throw after this is cleared,
4382 otherwise handle_zombie_lwp_error would get confused. */
4384 lwp->stop_reason = TARGET_STOPPED_BY_NO_REASON;
4387 /* Called when we try to resume a stopped LWP and that errors out. If
4388 the LWP is no longer in ptrace-stopped state (meaning it's zombie,
4389 or about to become), discard the error, clear any pending status
4390 the LWP may have, and return true (we'll collect the exit status
4391 soon enough). Otherwise, return false. */
4394 check_ptrace_stopped_lwp_gone (struct lwp_info *lp)
4396 struct thread_info *thread = get_lwp_thread (lp);
4398 /* If we get an error after resuming the LWP successfully, we'd
4399 confuse !T state for the LWP being gone. */
4400 gdb_assert (lp->stopped);
4402 /* We can't just check whether the LWP is in 'Z (Zombie)' state,
4403 because even if ptrace failed with ESRCH, the tracee may be "not
4404 yet fully dead", but already refusing ptrace requests. In that
4405 case the tracee has 'R (Running)' state for a little bit
4406 (observed in Linux 3.18). See also the note on ESRCH in the
4407 ptrace(2) man page. Instead, check whether the LWP has any state
4408 other than ptrace-stopped. */
4410 /* Don't assume anything if /proc/PID/status can't be read. */
4411 if (linux_proc_pid_is_trace_stopped_nowarn (lwpid_of (thread)) == 0)
4413 lp->stop_reason = TARGET_STOPPED_BY_NO_REASON;
4414 lp->status_pending_p = 0;
4420 /* Like linux_resume_one_lwp_throw, but no error is thrown if the LWP
4421 disappears while we try to resume it. */
4424 linux_resume_one_lwp (struct lwp_info *lwp,
4425 int step, int signal, siginfo_t *info)
4429 linux_resume_one_lwp_throw (lwp, step, signal, info);
4431 CATCH (ex, RETURN_MASK_ERROR)
4433 if (!check_ptrace_stopped_lwp_gone (lwp))
4434 throw_exception (ex);
4439 struct thread_resume_array
4441 struct thread_resume *resume;
4445 /* This function is called once per thread via find_inferior.
4446 ARG is a pointer to a thread_resume_array struct.
4447 We look up the thread specified by ENTRY in ARG, and mark the thread
4448 with a pointer to the appropriate resume request.
4450 This algorithm is O(threads * resume elements), but resume elements
4451 is small (and will remain small at least until GDB supports thread
4455 linux_set_resume_request (struct inferior_list_entry *entry, void *arg)
4457 struct thread_info *thread = (struct thread_info *) entry;
4458 struct lwp_info *lwp = get_thread_lwp (thread);
4460 struct thread_resume_array *r;
4462 r = (struct thread_resume_array *) arg;
4464 for (ndx = 0; ndx < r->n; ndx++)
4466 ptid_t ptid = r->resume[ndx].thread;
4467 if (ptid_equal (ptid, minus_one_ptid)
4468 || ptid_equal (ptid, entry->id)
4469 /* Handle both 'pPID' and 'pPID.-1' as meaning 'all threads
4471 || (ptid_get_pid (ptid) == pid_of (thread)
4472 && (ptid_is_pid (ptid)
4473 || ptid_get_lwp (ptid) == -1)))
4475 if (r->resume[ndx].kind == resume_stop
4476 && thread->last_resume_kind == resume_stop)
4479 debug_printf ("already %s LWP %ld at GDB's request\n",
4480 (thread->last_status.kind
4481 == TARGET_WAITKIND_STOPPED)
4489 lwp->resume = &r->resume[ndx];
4490 thread->last_resume_kind = lwp->resume->kind;
4492 lwp->step_range_start = lwp->resume->step_range_start;
4493 lwp->step_range_end = lwp->resume->step_range_end;
4495 /* If we had a deferred signal to report, dequeue one now.
4496 This can happen if LWP gets more than one signal while
4497 trying to get out of a jump pad. */
4499 && !lwp->status_pending_p
4500 && dequeue_one_deferred_signal (lwp, &lwp->status_pending))
4502 lwp->status_pending_p = 1;
4505 debug_printf ("Dequeueing deferred signal %d for LWP %ld, "
4506 "leaving status pending.\n",
4507 WSTOPSIG (lwp->status_pending),
4515 /* No resume action for this thread. */
4521 /* find_inferior callback for linux_resume.
4522 Set *FLAG_P if this lwp has an interesting status pending. */
4525 resume_status_pending_p (struct inferior_list_entry *entry, void *flag_p)
4527 struct thread_info *thread = (struct thread_info *) entry;
4528 struct lwp_info *lwp = get_thread_lwp (thread);
4530 /* LWPs which will not be resumed are not interesting, because
4531 we might not wait for them next time through linux_wait. */
4532 if (lwp->resume == NULL)
4535 if (thread_still_has_status_pending_p (thread))
4536 * (int *) flag_p = 1;
4541 /* Return 1 if this lwp that GDB wants running is stopped at an
4542 internal breakpoint that we need to step over. It assumes that any
4543 required STOP_PC adjustment has already been propagated to the
4544 inferior's regcache. */
4547 need_step_over_p (struct inferior_list_entry *entry, void *dummy)
4549 struct thread_info *thread = (struct thread_info *) entry;
4550 struct lwp_info *lwp = get_thread_lwp (thread);
4551 struct thread_info *saved_thread;
4553 struct process_info *proc = get_thread_process (thread);
4555 /* GDBserver is skipping the extra traps from the wrapper program,
4556 don't have to do step over. */
4557 if (proc->tdesc == NULL)
4560 /* LWPs which will not be resumed are not interesting, because we
4561 might not wait for them next time through linux_wait. */
4566 debug_printf ("Need step over [LWP %ld]? Ignoring, not stopped\n",
4571 if (thread->last_resume_kind == resume_stop)
4574 debug_printf ("Need step over [LWP %ld]? Ignoring, should remain"
4580 gdb_assert (lwp->suspended >= 0);
4585 debug_printf ("Need step over [LWP %ld]? Ignoring, suspended\n",
4590 if (lwp->status_pending_p)
4593 debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
4599 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
4603 /* If the PC has changed since we stopped, then don't do anything,
4604 and let the breakpoint/tracepoint be hit. This happens if, for
4605 instance, GDB handled the decr_pc_after_break subtraction itself,
4606 GDB is OOL stepping this thread, or the user has issued a "jump"
4607 command, or poked thread's registers herself. */
4608 if (pc != lwp->stop_pc)
4611 debug_printf ("Need step over [LWP %ld]? Cancelling, PC was changed. "
4612 "Old stop_pc was 0x%s, PC is now 0x%s\n",
4614 paddress (lwp->stop_pc), paddress (pc));
4618 /* On software single step target, resume the inferior with signal
4619 rather than stepping over. */
4620 if (can_software_single_step ()
4621 && lwp->pending_signals != NULL
4622 && lwp_signal_can_be_delivered (lwp))
4625 debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
4632 saved_thread = current_thread;
4633 current_thread = thread;
4635 /* We can only step over breakpoints we know about. */
4636 if (breakpoint_here (pc) || fast_tracepoint_jump_here (pc))
4638 /* Don't step over a breakpoint that GDB expects to hit
4639 though. If the condition is being evaluated on the target's side
4640 and it evaluate to false, step over this breakpoint as well. */
4641 if (gdb_breakpoint_here (pc)
4642 && gdb_condition_true_at_breakpoint (pc)
4643 && gdb_no_commands_at_breakpoint (pc))
4646 debug_printf ("Need step over [LWP %ld]? yes, but found"
4647 " GDB breakpoint at 0x%s; skipping step over\n",
4648 lwpid_of (thread), paddress (pc));
4650 current_thread = saved_thread;
4656 debug_printf ("Need step over [LWP %ld]? yes, "
4657 "found breakpoint at 0x%s\n",
4658 lwpid_of (thread), paddress (pc));
4660 /* We've found an lwp that needs stepping over --- return 1 so
4661 that find_inferior stops looking. */
4662 current_thread = saved_thread;
4668 current_thread = saved_thread;
4671 debug_printf ("Need step over [LWP %ld]? No, no breakpoint found"
4673 lwpid_of (thread), paddress (pc));
4678 /* Start a step-over operation on LWP. When LWP stopped at a
4679 breakpoint, to make progress, we need to remove the breakpoint out
4680 of the way. If we let other threads run while we do that, they may
4681 pass by the breakpoint location and miss hitting it. To avoid
4682 that, a step-over momentarily stops all threads while LWP is
4683 single-stepped by either hardware or software while the breakpoint
4684 is temporarily uninserted from the inferior. When the single-step
4685 finishes, we reinsert the breakpoint, and let all threads that are
4686 supposed to be running, run again. */
4689 start_step_over (struct lwp_info *lwp)
4691 struct thread_info *thread = get_lwp_thread (lwp);
4692 struct thread_info *saved_thread;
4697 debug_printf ("Starting step-over on LWP %ld. Stopping all threads\n",
4700 stop_all_lwps (1, lwp);
4702 if (lwp->suspended != 0)
4704 internal_error (__FILE__, __LINE__,
4705 "LWP %ld suspended=%d\n", lwpid_of (thread),
4710 debug_printf ("Done stopping all threads for step-over.\n");
4712 /* Note, we should always reach here with an already adjusted PC,
4713 either by GDB (if we're resuming due to GDB's request), or by our
4714 caller, if we just finished handling an internal breakpoint GDB
4715 shouldn't care about. */
4718 saved_thread = current_thread;
4719 current_thread = thread;
4721 lwp->bp_reinsert = pc;
4722 uninsert_breakpoints_at (pc);
4723 uninsert_fast_tracepoint_jumps_at (pc);
4725 step = single_step (lwp);
4727 current_thread = saved_thread;
4729 linux_resume_one_lwp (lwp, step, 0, NULL);
4731 /* Require next event from this LWP. */
4732 step_over_bkpt = thread->entry.id;
4736 /* Finish a step-over. Reinsert the breakpoint we had uninserted in
4737 start_step_over, if still there, and delete any reinsert
4738 breakpoints we've set, on non hardware single-step targets. */
4741 finish_step_over (struct lwp_info *lwp)
4743 if (lwp->bp_reinsert != 0)
4745 struct thread_info *saved_thread = current_thread;
4748 debug_printf ("Finished step over.\n");
4750 current_thread = get_lwp_thread (lwp);
4752 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
4753 may be no breakpoint to reinsert there by now. */
4754 reinsert_breakpoints_at (lwp->bp_reinsert);
4755 reinsert_fast_tracepoint_jumps_at (lwp->bp_reinsert);
4757 lwp->bp_reinsert = 0;
4759 /* Delete any software-single-step reinsert breakpoints. No
4760 longer needed. We don't have to worry about other threads
4761 hitting this trap, and later not being able to explain it,
4762 because we were stepping over a breakpoint, and we hold all
4763 threads but LWP stopped while doing that. */
4764 if (!can_hardware_single_step ())
4766 gdb_assert (has_reinsert_breakpoints (current_process ()));
4767 delete_reinsert_breakpoints ();
4770 step_over_bkpt = null_ptid;
4771 current_thread = saved_thread;
4778 /* If there's a step over in progress, wait until all threads stop
4779 (that is, until the stepping thread finishes its step), and
4780 unsuspend all lwps. The stepping thread ends with its status
4781 pending, which is processed later when we get back to processing
4785 complete_ongoing_step_over (void)
4787 if (!ptid_equal (step_over_bkpt, null_ptid))
4789 struct lwp_info *lwp;
4794 debug_printf ("detach: step over in progress, finish it first\n");
4796 /* Passing NULL_PTID as filter indicates we want all events to
4797 be left pending. Eventually this returns when there are no
4798 unwaited-for children left. */
4799 ret = linux_wait_for_event_filtered (minus_one_ptid, null_ptid,
4801 gdb_assert (ret == -1);
4803 lwp = find_lwp_pid (step_over_bkpt);
4805 finish_step_over (lwp);
4806 step_over_bkpt = null_ptid;
4807 unsuspend_all_lwps (lwp);
4811 /* This function is called once per thread. We check the thread's resume
4812 request, which will tell us whether to resume, step, or leave the thread
4813 stopped; and what signal, if any, it should be sent.
4815 For threads which we aren't explicitly told otherwise, we preserve
4816 the stepping flag; this is used for stepping over gdbserver-placed
4819 If pending_flags was set in any thread, we queue any needed
4820 signals, since we won't actually resume. We already have a pending
4821 event to report, so we don't need to preserve any step requests;
4822 they should be re-issued if necessary. */
4825 linux_resume_one_thread (struct inferior_list_entry *entry, void *arg)
4827 struct thread_info *thread = (struct thread_info *) entry;
4828 struct lwp_info *lwp = get_thread_lwp (thread);
4830 int leave_all_stopped = * (int *) arg;
4833 if (lwp->resume == NULL)
4836 if (lwp->resume->kind == resume_stop)
4839 debug_printf ("resume_stop request for LWP %ld\n", lwpid_of (thread));
4844 debug_printf ("stopping LWP %ld\n", lwpid_of (thread));
4846 /* Stop the thread, and wait for the event asynchronously,
4847 through the event loop. */
4853 debug_printf ("already stopped LWP %ld\n",
4856 /* The LWP may have been stopped in an internal event that
4857 was not meant to be notified back to GDB (e.g., gdbserver
4858 breakpoint), so we should be reporting a stop event in
4861 /* If the thread already has a pending SIGSTOP, this is a
4862 no-op. Otherwise, something later will presumably resume
4863 the thread and this will cause it to cancel any pending
4864 operation, due to last_resume_kind == resume_stop. If
4865 the thread already has a pending status to report, we
4866 will still report it the next time we wait - see
4867 status_pending_p_callback. */
4869 /* If we already have a pending signal to report, then
4870 there's no need to queue a SIGSTOP, as this means we're
4871 midway through moving the LWP out of the jumppad, and we
4872 will report the pending signal as soon as that is
4874 if (lwp->pending_signals_to_report == NULL)
4878 /* For stop requests, we're done. */
4880 thread->last_status.kind = TARGET_WAITKIND_IGNORE;
4884 /* If this thread which is about to be resumed has a pending status,
4885 then don't resume it - we can just report the pending status.
4886 Likewise if it is suspended, because e.g., another thread is
4887 stepping past a breakpoint. Make sure to queue any signals that
4888 would otherwise be sent. In all-stop mode, we do this decision
4889 based on if *any* thread has a pending status. If there's a
4890 thread that needs the step-over-breakpoint dance, then don't
4891 resume any other thread but that particular one. */
4892 leave_pending = (lwp->suspended
4893 || lwp->status_pending_p
4894 || leave_all_stopped);
4899 debug_printf ("resuming LWP %ld\n", lwpid_of (thread));
4901 step = (lwp->resume->kind == resume_step);
4902 linux_resume_one_lwp (lwp, step, lwp->resume->sig, NULL);
4907 debug_printf ("leaving LWP %ld stopped\n", lwpid_of (thread));
4909 /* If we have a new signal, enqueue the signal. */
4910 if (lwp->resume->sig != 0)
4912 struct pending_signals *p_sig = XCNEW (struct pending_signals);
4914 p_sig->prev = lwp->pending_signals;
4915 p_sig->signal = lwp->resume->sig;
4917 /* If this is the same signal we were previously stopped by,
4918 make sure to queue its siginfo. We can ignore the return
4919 value of ptrace; if it fails, we'll skip
4920 PTRACE_SETSIGINFO. */
4921 if (WIFSTOPPED (lwp->last_status)
4922 && WSTOPSIG (lwp->last_status) == lwp->resume->sig)
4923 ptrace (PTRACE_GETSIGINFO, lwpid_of (thread), (PTRACE_TYPE_ARG3) 0,
4926 lwp->pending_signals = p_sig;
4930 thread->last_status.kind = TARGET_WAITKIND_IGNORE;
4936 linux_resume (struct thread_resume *resume_info, size_t n)
4938 struct thread_resume_array array = { resume_info, n };
4939 struct thread_info *need_step_over = NULL;
4941 int leave_all_stopped;
4946 debug_printf ("linux_resume:\n");
4949 find_inferior (&all_threads, linux_set_resume_request, &array);
4951 /* If there is a thread which would otherwise be resumed, which has
4952 a pending status, then don't resume any threads - we can just
4953 report the pending status. Make sure to queue any signals that
4954 would otherwise be sent. In non-stop mode, we'll apply this
4955 logic to each thread individually. We consume all pending events
4956 before considering to start a step-over (in all-stop). */
4959 find_inferior (&all_threads, resume_status_pending_p, &any_pending);
4961 /* If there is a thread which would otherwise be resumed, which is
4962 stopped at a breakpoint that needs stepping over, then don't
4963 resume any threads - have it step over the breakpoint with all
4964 other threads stopped, then resume all threads again. Make sure
4965 to queue any signals that would otherwise be delivered or
4967 if (!any_pending && supports_breakpoints ())
4969 = (struct thread_info *) find_inferior (&all_threads,
4970 need_step_over_p, NULL);
4972 leave_all_stopped = (need_step_over != NULL || any_pending);
4976 if (need_step_over != NULL)
4977 debug_printf ("Not resuming all, need step over\n");
4978 else if (any_pending)
4979 debug_printf ("Not resuming, all-stop and found "
4980 "an LWP with pending status\n");
4982 debug_printf ("Resuming, no pending status or step over needed\n");
4985 /* Even if we're leaving threads stopped, queue all signals we'd
4986 otherwise deliver. */
4987 find_inferior (&all_threads, linux_resume_one_thread, &leave_all_stopped);
4990 start_step_over (get_thread_lwp (need_step_over));
4994 debug_printf ("linux_resume done\n");
4998 /* We may have events that were pending that can/should be sent to
4999 the client now. Trigger a linux_wait call. */
5000 if (target_is_async_p ())
5004 /* This function is called once per thread. We check the thread's
5005 last resume request, which will tell us whether to resume, step, or
5006 leave the thread stopped. Any signal the client requested to be
5007 delivered has already been enqueued at this point.
5009 If any thread that GDB wants running is stopped at an internal
5010 breakpoint that needs stepping over, we start a step-over operation
5011 on that particular thread, and leave all others stopped. */
5014 proceed_one_lwp (struct inferior_list_entry *entry, void *except)
5016 struct thread_info *thread = (struct thread_info *) entry;
5017 struct lwp_info *lwp = get_thread_lwp (thread);
5024 debug_printf ("proceed_one_lwp: lwp %ld\n", lwpid_of (thread));
5029 debug_printf (" LWP %ld already running\n", lwpid_of (thread));
5033 if (thread->last_resume_kind == resume_stop
5034 && thread->last_status.kind != TARGET_WAITKIND_IGNORE)
5037 debug_printf (" client wants LWP to remain %ld stopped\n",
5042 if (lwp->status_pending_p)
5045 debug_printf (" LWP %ld has pending status, leaving stopped\n",
5050 gdb_assert (lwp->suspended >= 0);
5055 debug_printf (" LWP %ld is suspended\n", lwpid_of (thread));
5059 if (thread->last_resume_kind == resume_stop
5060 && lwp->pending_signals_to_report == NULL
5061 && lwp->collecting_fast_tracepoint == 0)
5063 /* We haven't reported this LWP as stopped yet (otherwise, the
5064 last_status.kind check above would catch it, and we wouldn't
5065 reach here. This LWP may have been momentarily paused by a
5066 stop_all_lwps call while handling for example, another LWP's
5067 step-over. In that case, the pending expected SIGSTOP signal
5068 that was queued at vCont;t handling time will have already
5069 been consumed by wait_for_sigstop, and so we need to requeue
5070 another one here. Note that if the LWP already has a SIGSTOP
5071 pending, this is a no-op. */
5074 debug_printf ("Client wants LWP %ld to stop. "
5075 "Making sure it has a SIGSTOP pending\n",
5081 if (thread->last_resume_kind == resume_step)
5084 debug_printf (" stepping LWP %ld, client wants it stepping\n",
5088 else if (lwp->bp_reinsert != 0)
5091 debug_printf (" stepping LWP %ld, reinsert set\n",
5094 step = maybe_hw_step (thread);
5099 linux_resume_one_lwp (lwp, step, 0, NULL);
5104 unsuspend_and_proceed_one_lwp (struct inferior_list_entry *entry, void *except)
5106 struct thread_info *thread = (struct thread_info *) entry;
5107 struct lwp_info *lwp = get_thread_lwp (thread);
5112 lwp_suspended_decr (lwp);
5114 return proceed_one_lwp (entry, except);
5117 /* When we finish a step-over, set threads running again. If there's
5118 another thread that may need a step-over, now's the time to start
5119 it. Eventually, we'll move all threads past their breakpoints. */
5122 proceed_all_lwps (void)
5124 struct thread_info *need_step_over;
5126 /* If there is a thread which would otherwise be resumed, which is
5127 stopped at a breakpoint that needs stepping over, then don't
5128 resume any threads - have it step over the breakpoint with all
5129 other threads stopped, then resume all threads again. */
5131 if (supports_breakpoints ())
5134 = (struct thread_info *) find_inferior (&all_threads,
5135 need_step_over_p, NULL);
5137 if (need_step_over != NULL)
5140 debug_printf ("proceed_all_lwps: found "
5141 "thread %ld needing a step-over\n",
5142 lwpid_of (need_step_over));
5144 start_step_over (get_thread_lwp (need_step_over));
5150 debug_printf ("Proceeding, no step-over needed\n");
5152 find_inferior (&all_threads, proceed_one_lwp, NULL);
5155 /* Stopped LWPs that the client wanted to be running, that don't have
5156 pending statuses, are set to run again, except for EXCEPT, if not
5157 NULL. This undoes a stop_all_lwps call. */
5160 unstop_all_lwps (int unsuspend, struct lwp_info *except)
5166 debug_printf ("unstopping all lwps, except=(LWP %ld)\n",
5167 lwpid_of (get_lwp_thread (except)));
5169 debug_printf ("unstopping all lwps\n");
5173 find_inferior (&all_threads, unsuspend_and_proceed_one_lwp, except);
5175 find_inferior (&all_threads, proceed_one_lwp, except);
5179 debug_printf ("unstop_all_lwps done\n");
5185 #ifdef HAVE_LINUX_REGSETS
5187 #define use_linux_regsets 1
5189 /* Returns true if REGSET has been disabled. */
5192 regset_disabled (struct regsets_info *info, struct regset_info *regset)
5194 return (info->disabled_regsets != NULL
5195 && info->disabled_regsets[regset - info->regsets]);
5198 /* Disable REGSET. */
5201 disable_regset (struct regsets_info *info, struct regset_info *regset)
5205 dr_offset = regset - info->regsets;
5206 if (info->disabled_regsets == NULL)
5207 info->disabled_regsets = (char *) xcalloc (1, info->num_regsets);
5208 info->disabled_regsets[dr_offset] = 1;
5212 regsets_fetch_inferior_registers (struct regsets_info *regsets_info,
5213 struct regcache *regcache)
5215 struct regset_info *regset;
5216 int saw_general_regs = 0;
5220 pid = lwpid_of (current_thread);
5221 for (regset = regsets_info->regsets; regset->size >= 0; regset++)
5226 if (regset->size == 0 || regset_disabled (regsets_info, regset))
5229 buf = xmalloc (regset->size);
5231 nt_type = regset->nt_type;
5235 iov.iov_len = regset->size;
5236 data = (void *) &iov;
5242 res = ptrace (regset->get_request, pid,
5243 (PTRACE_TYPE_ARG3) (long) nt_type, data);
5245 res = ptrace (regset->get_request, pid, data, nt_type);
5251 /* If we get EIO on a regset, do not try it again for
5252 this process mode. */
5253 disable_regset (regsets_info, regset);
5255 else if (errno == ENODATA)
5257 /* ENODATA may be returned if the regset is currently
5258 not "active". This can happen in normal operation,
5259 so suppress the warning in this case. */
5264 sprintf (s, "ptrace(regsets_fetch_inferior_registers) PID=%d",
5271 if (regset->type == GENERAL_REGS)
5272 saw_general_regs = 1;
5273 regset->store_function (regcache, buf);
5277 if (saw_general_regs)
5284 regsets_store_inferior_registers (struct regsets_info *regsets_info,
5285 struct regcache *regcache)
5287 struct regset_info *regset;
5288 int saw_general_regs = 0;
5292 pid = lwpid_of (current_thread);
5293 for (regset = regsets_info->regsets; regset->size >= 0; regset++)
5298 if (regset->size == 0 || regset_disabled (regsets_info, regset)
5299 || regset->fill_function == NULL)
5302 buf = xmalloc (regset->size);
5304 /* First fill the buffer with the current register set contents,
5305 in case there are any items in the kernel's regset that are
5306 not in gdbserver's regcache. */
5308 nt_type = regset->nt_type;
5312 iov.iov_len = regset->size;
5313 data = (void *) &iov;
5319 res = ptrace (regset->get_request, pid,
5320 (PTRACE_TYPE_ARG3) (long) nt_type, data);
5322 res = ptrace (regset->get_request, pid, data, nt_type);
5327 /* Then overlay our cached registers on that. */
5328 regset->fill_function (regcache, buf);
5330 /* Only now do we write the register set. */
5332 res = ptrace (regset->set_request, pid,
5333 (PTRACE_TYPE_ARG3) (long) nt_type, data);
5335 res = ptrace (regset->set_request, pid, data, nt_type);
5343 /* If we get EIO on a regset, do not try it again for
5344 this process mode. */
5345 disable_regset (regsets_info, regset);
5347 else if (errno == ESRCH)
5349 /* At this point, ESRCH should mean the process is
5350 already gone, in which case we simply ignore attempts
5351 to change its registers. See also the related
5352 comment in linux_resume_one_lwp. */
5358 perror ("Warning: ptrace(regsets_store_inferior_registers)");
5361 else if (regset->type == GENERAL_REGS)
5362 saw_general_regs = 1;
5365 if (saw_general_regs)
5371 #else /* !HAVE_LINUX_REGSETS */
5373 #define use_linux_regsets 0
5374 #define regsets_fetch_inferior_registers(regsets_info, regcache) 1
5375 #define regsets_store_inferior_registers(regsets_info, regcache) 1
5379 /* Return 1 if register REGNO is supported by one of the regset ptrace
5380 calls or 0 if it has to be transferred individually. */
5383 linux_register_in_regsets (const struct regs_info *regs_info, int regno)
5385 unsigned char mask = 1 << (regno % 8);
5386 size_t index = regno / 8;
5388 return (use_linux_regsets
5389 && (regs_info->regset_bitmap == NULL
5390 || (regs_info->regset_bitmap[index] & mask) != 0));
5393 #ifdef HAVE_LINUX_USRREGS
5396 register_addr (const struct usrregs_info *usrregs, int regnum)
5400 if (regnum < 0 || regnum >= usrregs->num_regs)
5401 error ("Invalid register number %d.", regnum);
5403 addr = usrregs->regmap[regnum];
5408 /* Fetch one register. */
5410 fetch_register (const struct usrregs_info *usrregs,
5411 struct regcache *regcache, int regno)
5418 if (regno >= usrregs->num_regs)
5420 if ((*the_low_target.cannot_fetch_register) (regno))
5423 regaddr = register_addr (usrregs, regno);
5427 size = ((register_size (regcache->tdesc, regno)
5428 + sizeof (PTRACE_XFER_TYPE) - 1)
5429 & -sizeof (PTRACE_XFER_TYPE));
5430 buf = (char *) alloca (size);
5432 pid = lwpid_of (current_thread);
5433 for (i = 0; i < size; i += sizeof (PTRACE_XFER_TYPE))
5436 *(PTRACE_XFER_TYPE *) (buf + i) =
5437 ptrace (PTRACE_PEEKUSER, pid,
5438 /* Coerce to a uintptr_t first to avoid potential gcc warning
5439 of coercing an 8 byte integer to a 4 byte pointer. */
5440 (PTRACE_TYPE_ARG3) (uintptr_t) regaddr, (PTRACE_TYPE_ARG4) 0);
5441 regaddr += sizeof (PTRACE_XFER_TYPE);
5443 error ("reading register %d: %s", regno, strerror (errno));
5446 if (the_low_target.supply_ptrace_register)
5447 the_low_target.supply_ptrace_register (regcache, regno, buf);
5449 supply_register (regcache, regno, buf);
5452 /* Store one register. */
5454 store_register (const struct usrregs_info *usrregs,
5455 struct regcache *regcache, int regno)
5462 if (regno >= usrregs->num_regs)
5464 if ((*the_low_target.cannot_store_register) (regno))
5467 regaddr = register_addr (usrregs, regno);
5471 size = ((register_size (regcache->tdesc, regno)
5472 + sizeof (PTRACE_XFER_TYPE) - 1)
5473 & -sizeof (PTRACE_XFER_TYPE));
5474 buf = (char *) alloca (size);
5475 memset (buf, 0, size);
5477 if (the_low_target.collect_ptrace_register)
5478 the_low_target.collect_ptrace_register (regcache, regno, buf);
5480 collect_register (regcache, regno, buf);
5482 pid = lwpid_of (current_thread);
5483 for (i = 0; i < size; i += sizeof (PTRACE_XFER_TYPE))
5486 ptrace (PTRACE_POKEUSER, pid,
5487 /* Coerce to a uintptr_t first to avoid potential gcc warning
5488 about coercing an 8 byte integer to a 4 byte pointer. */
5489 (PTRACE_TYPE_ARG3) (uintptr_t) regaddr,
5490 (PTRACE_TYPE_ARG4) *(PTRACE_XFER_TYPE *) (buf + i));
5493 /* At this point, ESRCH should mean the process is
5494 already gone, in which case we simply ignore attempts
5495 to change its registers. See also the related
5496 comment in linux_resume_one_lwp. */
5500 if ((*the_low_target.cannot_store_register) (regno) == 0)
5501 error ("writing register %d: %s", regno, strerror (errno));
5503 regaddr += sizeof (PTRACE_XFER_TYPE);
5507 /* Fetch all registers, or just one, from the child process.
5508 If REGNO is -1, do this for all registers, skipping any that are
5509 assumed to have been retrieved by regsets_fetch_inferior_registers,
5510 unless ALL is non-zero.
5511 Otherwise, REGNO specifies which register (so we can save time). */
5513 usr_fetch_inferior_registers (const struct regs_info *regs_info,
5514 struct regcache *regcache, int regno, int all)
5516 struct usrregs_info *usr = regs_info->usrregs;
5520 for (regno = 0; regno < usr->num_regs; regno++)
5521 if (all || !linux_register_in_regsets (regs_info, regno))
5522 fetch_register (usr, regcache, regno);
5525 fetch_register (usr, regcache, regno);
5528 /* Store our register values back into the inferior.
5529 If REGNO is -1, do this for all registers, skipping any that are
5530 assumed to have been saved by regsets_store_inferior_registers,
5531 unless ALL is non-zero.
5532 Otherwise, REGNO specifies which register (so we can save time). */
5534 usr_store_inferior_registers (const struct regs_info *regs_info,
5535 struct regcache *regcache, int regno, int all)
5537 struct usrregs_info *usr = regs_info->usrregs;
5541 for (regno = 0; regno < usr->num_regs; regno++)
5542 if (all || !linux_register_in_regsets (regs_info, regno))
5543 store_register (usr, regcache, regno);
5546 store_register (usr, regcache, regno);
5549 #else /* !HAVE_LINUX_USRREGS */
5551 #define usr_fetch_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
5552 #define usr_store_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
5558 linux_fetch_registers (struct regcache *regcache, int regno)
5562 const struct regs_info *regs_info = (*the_low_target.regs_info) ();
5566 if (the_low_target.fetch_register != NULL
5567 && regs_info->usrregs != NULL)
5568 for (regno = 0; regno < regs_info->usrregs->num_regs; regno++)
5569 (*the_low_target.fetch_register) (regcache, regno);
5571 all = regsets_fetch_inferior_registers (regs_info->regsets_info, regcache);
5572 if (regs_info->usrregs != NULL)
5573 usr_fetch_inferior_registers (regs_info, regcache, -1, all);
5577 if (the_low_target.fetch_register != NULL
5578 && (*the_low_target.fetch_register) (regcache, regno))
5581 use_regsets = linux_register_in_regsets (regs_info, regno);
5583 all = regsets_fetch_inferior_registers (regs_info->regsets_info,
5585 if ((!use_regsets || all) && regs_info->usrregs != NULL)
5586 usr_fetch_inferior_registers (regs_info, regcache, regno, 1);
5591 linux_store_registers (struct regcache *regcache, int regno)
5595 const struct regs_info *regs_info = (*the_low_target.regs_info) ();
5599 all = regsets_store_inferior_registers (regs_info->regsets_info,
5601 if (regs_info->usrregs != NULL)
5602 usr_store_inferior_registers (regs_info, regcache, regno, all);
5606 use_regsets = linux_register_in_regsets (regs_info, regno);
5608 all = regsets_store_inferior_registers (regs_info->regsets_info,
5610 if ((!use_regsets || all) && regs_info->usrregs != NULL)
5611 usr_store_inferior_registers (regs_info, regcache, regno, 1);
5616 /* Copy LEN bytes from inferior's memory starting at MEMADDR
5617 to debugger memory starting at MYADDR. */
5620 linux_read_memory (CORE_ADDR memaddr, unsigned char *myaddr, int len)
5622 int pid = lwpid_of (current_thread);
5623 register PTRACE_XFER_TYPE *buffer;
5624 register CORE_ADDR addr;
5631 /* Try using /proc. Don't bother for one word. */
5632 if (len >= 3 * sizeof (long))
5636 /* We could keep this file open and cache it - possibly one per
5637 thread. That requires some juggling, but is even faster. */
5638 sprintf (filename, "/proc/%d/mem", pid);
5639 fd = open (filename, O_RDONLY | O_LARGEFILE);
5643 /* If pread64 is available, use it. It's faster if the kernel
5644 supports it (only one syscall), and it's 64-bit safe even on
5645 32-bit platforms (for instance, SPARC debugging a SPARC64
5648 bytes = pread64 (fd, myaddr, len, memaddr);
5651 if (lseek (fd, memaddr, SEEK_SET) != -1)
5652 bytes = read (fd, myaddr, len);
5659 /* Some data was read, we'll try to get the rest with ptrace. */
5669 /* Round starting address down to longword boundary. */
5670 addr = memaddr & -(CORE_ADDR) sizeof (PTRACE_XFER_TYPE);
5671 /* Round ending address up; get number of longwords that makes. */
5672 count = ((((memaddr + len) - addr) + sizeof (PTRACE_XFER_TYPE) - 1)
5673 / sizeof (PTRACE_XFER_TYPE));
5674 /* Allocate buffer of that many longwords. */
5675 buffer = XALLOCAVEC (PTRACE_XFER_TYPE, count);
5677 /* Read all the longwords */
5679 for (i = 0; i < count; i++, addr += sizeof (PTRACE_XFER_TYPE))
5681 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5682 about coercing an 8 byte integer to a 4 byte pointer. */
5683 buffer[i] = ptrace (PTRACE_PEEKTEXT, pid,
5684 (PTRACE_TYPE_ARG3) (uintptr_t) addr,
5685 (PTRACE_TYPE_ARG4) 0);
5691 /* Copy appropriate bytes out of the buffer. */
5694 i *= sizeof (PTRACE_XFER_TYPE);
5695 i -= memaddr & (sizeof (PTRACE_XFER_TYPE) - 1);
5697 (char *) buffer + (memaddr & (sizeof (PTRACE_XFER_TYPE) - 1)),
5704 /* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
5705 memory at MEMADDR. On failure (cannot write to the inferior)
5706 returns the value of errno. Always succeeds if LEN is zero. */
5709 linux_write_memory (CORE_ADDR memaddr, const unsigned char *myaddr, int len)
5712 /* Round starting address down to longword boundary. */
5713 register CORE_ADDR addr = memaddr & -(CORE_ADDR) sizeof (PTRACE_XFER_TYPE);
5714 /* Round ending address up; get number of longwords that makes. */
5716 = (((memaddr + len) - addr) + sizeof (PTRACE_XFER_TYPE) - 1)
5717 / sizeof (PTRACE_XFER_TYPE);
5719 /* Allocate buffer of that many longwords. */
5720 register PTRACE_XFER_TYPE *buffer = XALLOCAVEC (PTRACE_XFER_TYPE, count);
5722 int pid = lwpid_of (current_thread);
5726 /* Zero length write always succeeds. */
5732 /* Dump up to four bytes. */
5733 char str[4 * 2 + 1];
5735 int dump = len < 4 ? len : 4;
5737 for (i = 0; i < dump; i++)
5739 sprintf (p, "%02x", myaddr[i]);
5744 debug_printf ("Writing %s to 0x%08lx in process %d\n",
5745 str, (long) memaddr, pid);
5748 /* Fill start and end extra bytes of buffer with existing memory data. */
5751 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5752 about coercing an 8 byte integer to a 4 byte pointer. */
5753 buffer[0] = ptrace (PTRACE_PEEKTEXT, pid,
5754 (PTRACE_TYPE_ARG3) (uintptr_t) addr,
5755 (PTRACE_TYPE_ARG4) 0);
5763 = ptrace (PTRACE_PEEKTEXT, pid,
5764 /* Coerce to a uintptr_t first to avoid potential gcc warning
5765 about coercing an 8 byte integer to a 4 byte pointer. */
5766 (PTRACE_TYPE_ARG3) (uintptr_t) (addr + (count - 1)
5767 * sizeof (PTRACE_XFER_TYPE)),
5768 (PTRACE_TYPE_ARG4) 0);
5773 /* Copy data to be written over corresponding part of buffer. */
5775 memcpy ((char *) buffer + (memaddr & (sizeof (PTRACE_XFER_TYPE) - 1)),
5778 /* Write the entire buffer. */
5780 for (i = 0; i < count; i++, addr += sizeof (PTRACE_XFER_TYPE))
5783 ptrace (PTRACE_POKETEXT, pid,
5784 /* Coerce to a uintptr_t first to avoid potential gcc warning
5785 about coercing an 8 byte integer to a 4 byte pointer. */
5786 (PTRACE_TYPE_ARG3) (uintptr_t) addr,
5787 (PTRACE_TYPE_ARG4) buffer[i]);
5796 linux_look_up_symbols (void)
5798 #ifdef USE_THREAD_DB
5799 struct process_info *proc = current_process ();
5801 if (proc->priv->thread_db != NULL)
5809 linux_request_interrupt (void)
5811 extern unsigned long signal_pid;
5813 /* Send a SIGINT to the process group. This acts just like the user
5814 typed a ^C on the controlling terminal. */
5815 kill (-signal_pid, SIGINT);
5818 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
5819 to debugger memory starting at MYADDR. */
5822 linux_read_auxv (CORE_ADDR offset, unsigned char *myaddr, unsigned int len)
5824 char filename[PATH_MAX];
5826 int pid = lwpid_of (current_thread);
5828 xsnprintf (filename, sizeof filename, "/proc/%d/auxv", pid);
5830 fd = open (filename, O_RDONLY);
5834 if (offset != (CORE_ADDR) 0
5835 && lseek (fd, (off_t) offset, SEEK_SET) != (off_t) offset)
5838 n = read (fd, myaddr, len);
5845 /* These breakpoint and watchpoint related wrapper functions simply
5846 pass on the function call if the target has registered a
5847 corresponding function. */
5850 linux_supports_z_point_type (char z_type)
5852 return (the_low_target.supports_z_point_type != NULL
5853 && the_low_target.supports_z_point_type (z_type));
5857 linux_insert_point (enum raw_bkpt_type type, CORE_ADDR addr,
5858 int size, struct raw_breakpoint *bp)
5860 if (type == raw_bkpt_type_sw)
5861 return insert_memory_breakpoint (bp);
5862 else if (the_low_target.insert_point != NULL)
5863 return the_low_target.insert_point (type, addr, size, bp);
5865 /* Unsupported (see target.h). */
5870 linux_remove_point (enum raw_bkpt_type type, CORE_ADDR addr,
5871 int size, struct raw_breakpoint *bp)
5873 if (type == raw_bkpt_type_sw)
5874 return remove_memory_breakpoint (bp);
5875 else if (the_low_target.remove_point != NULL)
5876 return the_low_target.remove_point (type, addr, size, bp);
5878 /* Unsupported (see target.h). */
5882 /* Implement the to_stopped_by_sw_breakpoint target_ops
5886 linux_stopped_by_sw_breakpoint (void)
5888 struct lwp_info *lwp = get_thread_lwp (current_thread);
5890 return (lwp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT);
5893 /* Implement the to_supports_stopped_by_sw_breakpoint target_ops
5897 linux_supports_stopped_by_sw_breakpoint (void)
5899 return USE_SIGTRAP_SIGINFO;
5902 /* Implement the to_stopped_by_hw_breakpoint target_ops
5906 linux_stopped_by_hw_breakpoint (void)
5908 struct lwp_info *lwp = get_thread_lwp (current_thread);
5910 return (lwp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT);
5913 /* Implement the to_supports_stopped_by_hw_breakpoint target_ops
5917 linux_supports_stopped_by_hw_breakpoint (void)
5919 return USE_SIGTRAP_SIGINFO;
5922 /* Implement the supports_hardware_single_step target_ops method. */
5925 linux_supports_hardware_single_step (void)
5927 return can_hardware_single_step ();
5931 linux_supports_software_single_step (void)
5933 return can_software_single_step ();
5937 linux_stopped_by_watchpoint (void)
5939 struct lwp_info *lwp = get_thread_lwp (current_thread);
5941 return lwp->stop_reason == TARGET_STOPPED_BY_WATCHPOINT;
5945 linux_stopped_data_address (void)
5947 struct lwp_info *lwp = get_thread_lwp (current_thread);
5949 return lwp->stopped_data_address;
5952 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
5953 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
5954 && defined(PT_TEXT_END_ADDR)
5956 /* This is only used for targets that define PT_TEXT_ADDR,
5957 PT_DATA_ADDR and PT_TEXT_END_ADDR. If those are not defined, supposedly
5958 the target has different ways of acquiring this information, like
5961 /* Under uClinux, programs are loaded at non-zero offsets, which we need
5962 to tell gdb about. */
5965 linux_read_offsets (CORE_ADDR *text_p, CORE_ADDR *data_p)
5967 unsigned long text, text_end, data;
5968 int pid = lwpid_of (current_thread);
5972 text = ptrace (PTRACE_PEEKUSER, pid, (PTRACE_TYPE_ARG3) PT_TEXT_ADDR,
5973 (PTRACE_TYPE_ARG4) 0);
5974 text_end = ptrace (PTRACE_PEEKUSER, pid, (PTRACE_TYPE_ARG3) PT_TEXT_END_ADDR,
5975 (PTRACE_TYPE_ARG4) 0);
5976 data = ptrace (PTRACE_PEEKUSER, pid, (PTRACE_TYPE_ARG3) PT_DATA_ADDR,
5977 (PTRACE_TYPE_ARG4) 0);
5981 /* Both text and data offsets produced at compile-time (and so
5982 used by gdb) are relative to the beginning of the program,
5983 with the data segment immediately following the text segment.
5984 However, the actual runtime layout in memory may put the data
5985 somewhere else, so when we send gdb a data base-address, we
5986 use the real data base address and subtract the compile-time
5987 data base-address from it (which is just the length of the
5988 text segment). BSS immediately follows data in both
5991 *data_p = data - (text_end - text);
6000 linux_qxfer_osdata (const char *annex,
6001 unsigned char *readbuf, unsigned const char *writebuf,
6002 CORE_ADDR offset, int len)
6004 return linux_common_xfer_osdata (annex, readbuf, offset, len);
6007 /* Convert a native/host siginfo object, into/from the siginfo in the
6008 layout of the inferiors' architecture. */
6011 siginfo_fixup (siginfo_t *siginfo, gdb_byte *inf_siginfo, int direction)
6015 if (the_low_target.siginfo_fixup != NULL)
6016 done = the_low_target.siginfo_fixup (siginfo, inf_siginfo, direction);
6018 /* If there was no callback, or the callback didn't do anything,
6019 then just do a straight memcpy. */
6023 memcpy (siginfo, inf_siginfo, sizeof (siginfo_t));
6025 memcpy (inf_siginfo, siginfo, sizeof (siginfo_t));
6030 linux_xfer_siginfo (const char *annex, unsigned char *readbuf,
6031 unsigned const char *writebuf, CORE_ADDR offset, int len)
6035 gdb_byte inf_siginfo[sizeof (siginfo_t)];
6037 if (current_thread == NULL)
6040 pid = lwpid_of (current_thread);
6043 debug_printf ("%s siginfo for lwp %d.\n",
6044 readbuf != NULL ? "Reading" : "Writing",
6047 if (offset >= sizeof (siginfo))
6050 if (ptrace (PTRACE_GETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo) != 0)
6053 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
6054 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
6055 inferior with a 64-bit GDBSERVER should look the same as debugging it
6056 with a 32-bit GDBSERVER, we need to convert it. */
6057 siginfo_fixup (&siginfo, inf_siginfo, 0);
6059 if (offset + len > sizeof (siginfo))
6060 len = sizeof (siginfo) - offset;
6062 if (readbuf != NULL)
6063 memcpy (readbuf, inf_siginfo + offset, len);
6066 memcpy (inf_siginfo + offset, writebuf, len);
6068 /* Convert back to ptrace layout before flushing it out. */
6069 siginfo_fixup (&siginfo, inf_siginfo, 1);
6071 if (ptrace (PTRACE_SETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo) != 0)
6078 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
6079 so we notice when children change state; as the handler for the
6080 sigsuspend in my_waitpid. */
6083 sigchld_handler (int signo)
6085 int old_errno = errno;
6091 /* fprintf is not async-signal-safe, so call write
6093 if (write (2, "sigchld_handler\n",
6094 sizeof ("sigchld_handler\n") - 1) < 0)
6095 break; /* just ignore */
6099 if (target_is_async_p ())
6100 async_file_mark (); /* trigger a linux_wait */
6106 linux_supports_non_stop (void)
6112 linux_async (int enable)
6114 int previous = target_is_async_p ();
6117 debug_printf ("linux_async (%d), previous=%d\n",
6120 if (previous != enable)
6123 sigemptyset (&mask);
6124 sigaddset (&mask, SIGCHLD);
6126 sigprocmask (SIG_BLOCK, &mask, NULL);
6130 if (pipe (linux_event_pipe) == -1)
6132 linux_event_pipe[0] = -1;
6133 linux_event_pipe[1] = -1;
6134 sigprocmask (SIG_UNBLOCK, &mask, NULL);
6136 warning ("creating event pipe failed.");
6140 fcntl (linux_event_pipe[0], F_SETFL, O_NONBLOCK);
6141 fcntl (linux_event_pipe[1], F_SETFL, O_NONBLOCK);
6143 /* Register the event loop handler. */
6144 add_file_handler (linux_event_pipe[0],
6145 handle_target_event, NULL);
6147 /* Always trigger a linux_wait. */
6152 delete_file_handler (linux_event_pipe[0]);
6154 close (linux_event_pipe[0]);
6155 close (linux_event_pipe[1]);
6156 linux_event_pipe[0] = -1;
6157 linux_event_pipe[1] = -1;
6160 sigprocmask (SIG_UNBLOCK, &mask, NULL);
6167 linux_start_non_stop (int nonstop)
6169 /* Register or unregister from event-loop accordingly. */
6170 linux_async (nonstop);
6172 if (target_is_async_p () != (nonstop != 0))
6179 linux_supports_multi_process (void)
6184 /* Check if fork events are supported. */
6187 linux_supports_fork_events (void)
6189 return linux_supports_tracefork ();
6192 /* Check if vfork events are supported. */
6195 linux_supports_vfork_events (void)
6197 return linux_supports_tracefork ();
6200 /* Check if exec events are supported. */
6203 linux_supports_exec_events (void)
6205 return linux_supports_traceexec ();
6208 /* Callback for 'find_inferior'. Set the (possibly changed) ptrace
6209 options for the specified lwp. */
6212 reset_lwp_ptrace_options_callback (struct inferior_list_entry *entry,
6215 struct thread_info *thread = (struct thread_info *) entry;
6216 struct lwp_info *lwp = get_thread_lwp (thread);
6220 /* Stop the lwp so we can modify its ptrace options. */
6221 lwp->must_set_ptrace_flags = 1;
6222 linux_stop_lwp (lwp);
6226 /* Already stopped; go ahead and set the ptrace options. */
6227 struct process_info *proc = find_process_pid (pid_of (thread));
6228 int options = linux_low_ptrace_options (proc->attached);
6230 linux_enable_event_reporting (lwpid_of (thread), options);
6231 lwp->must_set_ptrace_flags = 0;
6237 /* Target hook for 'handle_new_gdb_connection'. Causes a reset of the
6238 ptrace flags for all inferiors. This is in case the new GDB connection
6239 doesn't support the same set of events that the previous one did. */
6242 linux_handle_new_gdb_connection (void)
6246 /* Request that all the lwps reset their ptrace options. */
6247 find_inferior (&all_threads, reset_lwp_ptrace_options_callback , &pid);
6251 linux_supports_disable_randomization (void)
6253 #ifdef HAVE_PERSONALITY
6261 linux_supports_agent (void)
6267 linux_supports_range_stepping (void)
6269 if (*the_low_target.supports_range_stepping == NULL)
6272 return (*the_low_target.supports_range_stepping) ();
6275 /* Enumerate spufs IDs for process PID. */
6277 spu_enumerate_spu_ids (long pid, unsigned char *buf, CORE_ADDR offset, int len)
6283 struct dirent *entry;
6285 sprintf (path, "/proc/%ld/fd", pid);
6286 dir = opendir (path);
6291 while ((entry = readdir (dir)) != NULL)
6297 fd = atoi (entry->d_name);
6301 sprintf (path, "/proc/%ld/fd/%d", pid, fd);
6302 if (stat (path, &st) != 0)
6304 if (!S_ISDIR (st.st_mode))
6307 if (statfs (path, &stfs) != 0)
6309 if (stfs.f_type != SPUFS_MAGIC)
6312 if (pos >= offset && pos + 4 <= offset + len)
6314 *(unsigned int *)(buf + pos - offset) = fd;
6324 /* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
6325 object type, using the /proc file system. */
6327 linux_qxfer_spu (const char *annex, unsigned char *readbuf,
6328 unsigned const char *writebuf,
6329 CORE_ADDR offset, int len)
6331 long pid = lwpid_of (current_thread);
6336 if (!writebuf && !readbuf)
6344 return spu_enumerate_spu_ids (pid, readbuf, offset, len);
6347 sprintf (buf, "/proc/%ld/fd/%s", pid, annex);
6348 fd = open (buf, writebuf? O_WRONLY : O_RDONLY);
6353 && lseek (fd, (off_t) offset, SEEK_SET) != (off_t) offset)
6360 ret = write (fd, writebuf, (size_t) len);
6362 ret = read (fd, readbuf, (size_t) len);
6368 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
6369 struct target_loadseg
6371 /* Core address to which the segment is mapped. */
6373 /* VMA recorded in the program header. */
6375 /* Size of this segment in memory. */
6379 # if defined PT_GETDSBT
6380 struct target_loadmap
6382 /* Protocol version number, must be zero. */
6384 /* Pointer to the DSBT table, its size, and the DSBT index. */
6385 unsigned *dsbt_table;
6386 unsigned dsbt_size, dsbt_index;
6387 /* Number of segments in this map. */
6389 /* The actual memory map. */
6390 struct target_loadseg segs[/*nsegs*/];
6392 # define LINUX_LOADMAP PT_GETDSBT
6393 # define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
6394 # define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
6396 struct target_loadmap
6398 /* Protocol version number, must be zero. */
6400 /* Number of segments in this map. */
6402 /* The actual memory map. */
6403 struct target_loadseg segs[/*nsegs*/];
6405 # define LINUX_LOADMAP PTRACE_GETFDPIC
6406 # define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
6407 # define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
6411 linux_read_loadmap (const char *annex, CORE_ADDR offset,
6412 unsigned char *myaddr, unsigned int len)
6414 int pid = lwpid_of (current_thread);
6416 struct target_loadmap *data = NULL;
6417 unsigned int actual_length, copy_length;
6419 if (strcmp (annex, "exec") == 0)
6420 addr = (int) LINUX_LOADMAP_EXEC;
6421 else if (strcmp (annex, "interp") == 0)
6422 addr = (int) LINUX_LOADMAP_INTERP;
6426 if (ptrace (LINUX_LOADMAP, pid, addr, &data) != 0)
6432 actual_length = sizeof (struct target_loadmap)
6433 + sizeof (struct target_loadseg) * data->nsegs;
6435 if (offset < 0 || offset > actual_length)
6438 copy_length = actual_length - offset < len ? actual_length - offset : len;
6439 memcpy (myaddr, (char *) data + offset, copy_length);
6443 # define linux_read_loadmap NULL
6444 #endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
6447 linux_process_qsupported (char **features, int count)
6449 if (the_low_target.process_qsupported != NULL)
6450 the_low_target.process_qsupported (features, count);
6454 linux_supports_catch_syscall (void)
6456 return (the_low_target.get_syscall_trapinfo != NULL
6457 && linux_supports_tracesysgood ());
6461 linux_get_ipa_tdesc_idx (void)
6463 if (the_low_target.get_ipa_tdesc_idx == NULL)
6466 return (*the_low_target.get_ipa_tdesc_idx) ();
6470 linux_supports_tracepoints (void)
6472 if (*the_low_target.supports_tracepoints == NULL)
6475 return (*the_low_target.supports_tracepoints) ();
6479 linux_read_pc (struct regcache *regcache)
6481 if (the_low_target.get_pc == NULL)
6484 return (*the_low_target.get_pc) (regcache);
6488 linux_write_pc (struct regcache *regcache, CORE_ADDR pc)
6490 gdb_assert (the_low_target.set_pc != NULL);
6492 (*the_low_target.set_pc) (regcache, pc);
6496 linux_thread_stopped (struct thread_info *thread)
6498 return get_thread_lwp (thread)->stopped;
6501 /* This exposes stop-all-threads functionality to other modules. */
6504 linux_pause_all (int freeze)
6506 stop_all_lwps (freeze, NULL);
6509 /* This exposes unstop-all-threads functionality to other gdbserver
6513 linux_unpause_all (int unfreeze)
6515 unstop_all_lwps (unfreeze, NULL);
6519 linux_prepare_to_access_memory (void)
6521 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6524 linux_pause_all (1);
6529 linux_done_accessing_memory (void)
6531 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6534 linux_unpause_all (1);
6538 linux_install_fast_tracepoint_jump_pad (CORE_ADDR tpoint, CORE_ADDR tpaddr,
6539 CORE_ADDR collector,
6542 CORE_ADDR *jump_entry,
6543 CORE_ADDR *trampoline,
6544 ULONGEST *trampoline_size,
6545 unsigned char *jjump_pad_insn,
6546 ULONGEST *jjump_pad_insn_size,
6547 CORE_ADDR *adjusted_insn_addr,
6548 CORE_ADDR *adjusted_insn_addr_end,
6551 return (*the_low_target.install_fast_tracepoint_jump_pad)
6552 (tpoint, tpaddr, collector, lockaddr, orig_size,
6553 jump_entry, trampoline, trampoline_size,
6554 jjump_pad_insn, jjump_pad_insn_size,
6555 adjusted_insn_addr, adjusted_insn_addr_end,
6559 static struct emit_ops *
6560 linux_emit_ops (void)
6562 if (the_low_target.emit_ops != NULL)
6563 return (*the_low_target.emit_ops) ();
6569 linux_get_min_fast_tracepoint_insn_len (void)
6571 return (*the_low_target.get_min_fast_tracepoint_insn_len) ();
6574 /* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
6577 get_phdr_phnum_from_proc_auxv (const int pid, const int is_elf64,
6578 CORE_ADDR *phdr_memaddr, int *num_phdr)
6580 char filename[PATH_MAX];
6582 const int auxv_size = is_elf64
6583 ? sizeof (Elf64_auxv_t) : sizeof (Elf32_auxv_t);
6584 char buf[sizeof (Elf64_auxv_t)]; /* The larger of the two. */
6586 xsnprintf (filename, sizeof filename, "/proc/%d/auxv", pid);
6588 fd = open (filename, O_RDONLY);
6594 while (read (fd, buf, auxv_size) == auxv_size
6595 && (*phdr_memaddr == 0 || *num_phdr == 0))
6599 Elf64_auxv_t *const aux = (Elf64_auxv_t *) buf;
6601 switch (aux->a_type)
6604 *phdr_memaddr = aux->a_un.a_val;
6607 *num_phdr = aux->a_un.a_val;
6613 Elf32_auxv_t *const aux = (Elf32_auxv_t *) buf;
6615 switch (aux->a_type)
6618 *phdr_memaddr = aux->a_un.a_val;
6621 *num_phdr = aux->a_un.a_val;
6629 if (*phdr_memaddr == 0 || *num_phdr == 0)
6631 warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
6632 "phdr_memaddr = %ld, phdr_num = %d",
6633 (long) *phdr_memaddr, *num_phdr);
6640 /* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
6643 get_dynamic (const int pid, const int is_elf64)
6645 CORE_ADDR phdr_memaddr, relocation;
6647 unsigned char *phdr_buf;
6648 const int phdr_size = is_elf64 ? sizeof (Elf64_Phdr) : sizeof (Elf32_Phdr);
6650 if (get_phdr_phnum_from_proc_auxv (pid, is_elf64, &phdr_memaddr, &num_phdr))
6653 gdb_assert (num_phdr < 100); /* Basic sanity check. */
6654 phdr_buf = (unsigned char *) alloca (num_phdr * phdr_size);
6656 if (linux_read_memory (phdr_memaddr, phdr_buf, num_phdr * phdr_size))
6659 /* Compute relocation: it is expected to be 0 for "regular" executables,
6660 non-zero for PIE ones. */
6662 for (i = 0; relocation == -1 && i < num_phdr; i++)
6665 Elf64_Phdr *const p = (Elf64_Phdr *) (phdr_buf + i * phdr_size);
6667 if (p->p_type == PT_PHDR)
6668 relocation = phdr_memaddr - p->p_vaddr;
6672 Elf32_Phdr *const p = (Elf32_Phdr *) (phdr_buf + i * phdr_size);
6674 if (p->p_type == PT_PHDR)
6675 relocation = phdr_memaddr - p->p_vaddr;
6678 if (relocation == -1)
6680 /* PT_PHDR is optional, but necessary for PIE in general. Fortunately
6681 any real world executables, including PIE executables, have always
6682 PT_PHDR present. PT_PHDR is not present in some shared libraries or
6683 in fpc (Free Pascal 2.4) binaries but neither of those have a need for
6684 or present DT_DEBUG anyway (fpc binaries are statically linked).
6686 Therefore if there exists DT_DEBUG there is always also PT_PHDR.
6688 GDB could find RELOCATION also from AT_ENTRY - e_entry. */
6693 for (i = 0; i < num_phdr; i++)
6697 Elf64_Phdr *const p = (Elf64_Phdr *) (phdr_buf + i * phdr_size);
6699 if (p->p_type == PT_DYNAMIC)
6700 return p->p_vaddr + relocation;
6704 Elf32_Phdr *const p = (Elf32_Phdr *) (phdr_buf + i * phdr_size);
6706 if (p->p_type == PT_DYNAMIC)
6707 return p->p_vaddr + relocation;
6714 /* Return &_r_debug in the inferior, or -1 if not present. Return value
6715 can be 0 if the inferior does not yet have the library list initialized.
6716 We look for DT_MIPS_RLD_MAP first. MIPS executables use this instead of
6717 DT_DEBUG, although they sometimes contain an unused DT_DEBUG entry too. */
6720 get_r_debug (const int pid, const int is_elf64)
6722 CORE_ADDR dynamic_memaddr;
6723 const int dyn_size = is_elf64 ? sizeof (Elf64_Dyn) : sizeof (Elf32_Dyn);
6724 unsigned char buf[sizeof (Elf64_Dyn)]; /* The larger of the two. */
6727 dynamic_memaddr = get_dynamic (pid, is_elf64);
6728 if (dynamic_memaddr == 0)
6731 while (linux_read_memory (dynamic_memaddr, buf, dyn_size) == 0)
6735 Elf64_Dyn *const dyn = (Elf64_Dyn *) buf;
6736 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
6740 unsigned char buf[sizeof (Elf64_Xword)];
6744 #ifdef DT_MIPS_RLD_MAP
6745 if (dyn->d_tag == DT_MIPS_RLD_MAP)
6747 if (linux_read_memory (dyn->d_un.d_val,
6748 rld_map.buf, sizeof (rld_map.buf)) == 0)
6753 #endif /* DT_MIPS_RLD_MAP */
6754 #ifdef DT_MIPS_RLD_MAP_REL
6755 if (dyn->d_tag == DT_MIPS_RLD_MAP_REL)
6757 if (linux_read_memory (dyn->d_un.d_val + dynamic_memaddr,
6758 rld_map.buf, sizeof (rld_map.buf)) == 0)
6763 #endif /* DT_MIPS_RLD_MAP_REL */
6765 if (dyn->d_tag == DT_DEBUG && map == -1)
6766 map = dyn->d_un.d_val;
6768 if (dyn->d_tag == DT_NULL)
6773 Elf32_Dyn *const dyn = (Elf32_Dyn *) buf;
6774 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
6778 unsigned char buf[sizeof (Elf32_Word)];
6782 #ifdef DT_MIPS_RLD_MAP
6783 if (dyn->d_tag == DT_MIPS_RLD_MAP)
6785 if (linux_read_memory (dyn->d_un.d_val,
6786 rld_map.buf, sizeof (rld_map.buf)) == 0)
6791 #endif /* DT_MIPS_RLD_MAP */
6792 #ifdef DT_MIPS_RLD_MAP_REL
6793 if (dyn->d_tag == DT_MIPS_RLD_MAP_REL)
6795 if (linux_read_memory (dyn->d_un.d_val + dynamic_memaddr,
6796 rld_map.buf, sizeof (rld_map.buf)) == 0)
6801 #endif /* DT_MIPS_RLD_MAP_REL */
6803 if (dyn->d_tag == DT_DEBUG && map == -1)
6804 map = dyn->d_un.d_val;
6806 if (dyn->d_tag == DT_NULL)
6810 dynamic_memaddr += dyn_size;
6816 /* Read one pointer from MEMADDR in the inferior. */
6819 read_one_ptr (CORE_ADDR memaddr, CORE_ADDR *ptr, int ptr_size)
6823 /* Go through a union so this works on either big or little endian
6824 hosts, when the inferior's pointer size is smaller than the size
6825 of CORE_ADDR. It is assumed the inferior's endianness is the
6826 same of the superior's. */
6829 CORE_ADDR core_addr;
6834 ret = linux_read_memory (memaddr, &addr.uc, ptr_size);
6837 if (ptr_size == sizeof (CORE_ADDR))
6838 *ptr = addr.core_addr;
6839 else if (ptr_size == sizeof (unsigned int))
6842 gdb_assert_not_reached ("unhandled pointer size");
6847 struct link_map_offsets
6849 /* Offset and size of r_debug.r_version. */
6850 int r_version_offset;
6852 /* Offset and size of r_debug.r_map. */
6855 /* Offset to l_addr field in struct link_map. */
6858 /* Offset to l_name field in struct link_map. */
6861 /* Offset to l_ld field in struct link_map. */
6864 /* Offset to l_next field in struct link_map. */
6867 /* Offset to l_prev field in struct link_map. */
6871 /* Construct qXfer:libraries-svr4:read reply. */
6874 linux_qxfer_libraries_svr4 (const char *annex, unsigned char *readbuf,
6875 unsigned const char *writebuf,
6876 CORE_ADDR offset, int len)
6879 unsigned document_len;
6880 struct process_info_private *const priv = current_process ()->priv;
6881 char filename[PATH_MAX];
6884 static const struct link_map_offsets lmo_32bit_offsets =
6886 0, /* r_version offset. */
6887 4, /* r_debug.r_map offset. */
6888 0, /* l_addr offset in link_map. */
6889 4, /* l_name offset in link_map. */
6890 8, /* l_ld offset in link_map. */
6891 12, /* l_next offset in link_map. */
6892 16 /* l_prev offset in link_map. */
6895 static const struct link_map_offsets lmo_64bit_offsets =
6897 0, /* r_version offset. */
6898 8, /* r_debug.r_map offset. */
6899 0, /* l_addr offset in link_map. */
6900 8, /* l_name offset in link_map. */
6901 16, /* l_ld offset in link_map. */
6902 24, /* l_next offset in link_map. */
6903 32 /* l_prev offset in link_map. */
6905 const struct link_map_offsets *lmo;
6906 unsigned int machine;
6908 CORE_ADDR lm_addr = 0, lm_prev = 0;
6909 int allocated = 1024;
6911 CORE_ADDR l_name, l_addr, l_ld, l_next, l_prev;
6912 int header_done = 0;
6914 if (writebuf != NULL)
6916 if (readbuf == NULL)
6919 pid = lwpid_of (current_thread);
6920 xsnprintf (filename, sizeof filename, "/proc/%d/exe", pid);
6921 is_elf64 = elf_64_file_p (filename, &machine);
6922 lmo = is_elf64 ? &lmo_64bit_offsets : &lmo_32bit_offsets;
6923 ptr_size = is_elf64 ? 8 : 4;
6925 while (annex[0] != '\0')
6931 sep = strchr (annex, '=');
6936 if (len == 5 && startswith (annex, "start"))
6938 else if (len == 4 && startswith (annex, "prev"))
6942 annex = strchr (sep, ';');
6949 annex = decode_address_to_semicolon (addrp, sep + 1);
6956 if (priv->r_debug == 0)
6957 priv->r_debug = get_r_debug (pid, is_elf64);
6959 /* We failed to find DT_DEBUG. Such situation will not change
6960 for this inferior - do not retry it. Report it to GDB as
6961 E01, see for the reasons at the GDB solib-svr4.c side. */
6962 if (priv->r_debug == (CORE_ADDR) -1)
6965 if (priv->r_debug != 0)
6967 if (linux_read_memory (priv->r_debug + lmo->r_version_offset,
6968 (unsigned char *) &r_version,
6969 sizeof (r_version)) != 0
6972 warning ("unexpected r_debug version %d", r_version);
6974 else if (read_one_ptr (priv->r_debug + lmo->r_map_offset,
6975 &lm_addr, ptr_size) != 0)
6977 warning ("unable to read r_map from 0x%lx",
6978 (long) priv->r_debug + lmo->r_map_offset);
6983 document = (char *) xmalloc (allocated);
6984 strcpy (document, "<library-list-svr4 version=\"1.0\"");
6985 p = document + strlen (document);
6988 && read_one_ptr (lm_addr + lmo->l_name_offset,
6989 &l_name, ptr_size) == 0
6990 && read_one_ptr (lm_addr + lmo->l_addr_offset,
6991 &l_addr, ptr_size) == 0
6992 && read_one_ptr (lm_addr + lmo->l_ld_offset,
6993 &l_ld, ptr_size) == 0
6994 && read_one_ptr (lm_addr + lmo->l_prev_offset,
6995 &l_prev, ptr_size) == 0
6996 && read_one_ptr (lm_addr + lmo->l_next_offset,
6997 &l_next, ptr_size) == 0)
6999 unsigned char libname[PATH_MAX];
7001 if (lm_prev != l_prev)
7003 warning ("Corrupted shared library list: 0x%lx != 0x%lx",
7004 (long) lm_prev, (long) l_prev);
7008 /* Ignore the first entry even if it has valid name as the first entry
7009 corresponds to the main executable. The first entry should not be
7010 skipped if the dynamic loader was loaded late by a static executable
7011 (see solib-svr4.c parameter ignore_first). But in such case the main
7012 executable does not have PT_DYNAMIC present and this function already
7013 exited above due to failed get_r_debug. */
7016 sprintf (p, " main-lm=\"0x%lx\"", (unsigned long) lm_addr);
7021 /* Not checking for error because reading may stop before
7022 we've got PATH_MAX worth of characters. */
7024 linux_read_memory (l_name, libname, sizeof (libname) - 1);
7025 libname[sizeof (libname) - 1] = '\0';
7026 if (libname[0] != '\0')
7028 /* 6x the size for xml_escape_text below. */
7029 size_t len = 6 * strlen ((char *) libname);
7034 /* Terminate `<library-list-svr4'. */
7039 while (allocated < p - document + len + 200)
7041 /* Expand to guarantee sufficient storage. */
7042 uintptr_t document_len = p - document;
7044 document = (char *) xrealloc (document, 2 * allocated);
7046 p = document + document_len;
7049 name = xml_escape_text ((char *) libname);
7050 p += sprintf (p, "<library name=\"%s\" lm=\"0x%lx\" "
7051 "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
7052 name, (unsigned long) lm_addr,
7053 (unsigned long) l_addr, (unsigned long) l_ld);
7064 /* Empty list; terminate `<library-list-svr4'. */
7068 strcpy (p, "</library-list-svr4>");
7070 document_len = strlen (document);
7071 if (offset < document_len)
7072 document_len -= offset;
7075 if (len > document_len)
7078 memcpy (readbuf, document + offset, len);
7084 #ifdef HAVE_LINUX_BTRACE
7086 /* See to_disable_btrace target method. */
7089 linux_low_disable_btrace (struct btrace_target_info *tinfo)
7091 enum btrace_error err;
7093 err = linux_disable_btrace (tinfo);
7094 return (err == BTRACE_ERR_NONE ? 0 : -1);
7097 /* Encode an Intel Processor Trace configuration. */
7100 linux_low_encode_pt_config (struct buffer *buffer,
7101 const struct btrace_data_pt_config *config)
7103 buffer_grow_str (buffer, "<pt-config>\n");
7105 switch (config->cpu.vendor)
7108 buffer_xml_printf (buffer, "<cpu vendor=\"GenuineIntel\" family=\"%u\" "
7109 "model=\"%u\" stepping=\"%u\"/>\n",
7110 config->cpu.family, config->cpu.model,
7111 config->cpu.stepping);
7118 buffer_grow_str (buffer, "</pt-config>\n");
7121 /* Encode a raw buffer. */
7124 linux_low_encode_raw (struct buffer *buffer, const gdb_byte *data,
7130 /* We use hex encoding - see common/rsp-low.h. */
7131 buffer_grow_str (buffer, "<raw>\n");
7137 elem[0] = tohex ((*data >> 4) & 0xf);
7138 elem[1] = tohex (*data++ & 0xf);
7140 buffer_grow (buffer, elem, 2);
7143 buffer_grow_str (buffer, "</raw>\n");
7146 /* See to_read_btrace target method. */
7149 linux_low_read_btrace (struct btrace_target_info *tinfo, struct buffer *buffer,
7150 enum btrace_read_type type)
7152 struct btrace_data btrace;
7153 struct btrace_block *block;
7154 enum btrace_error err;
7157 btrace_data_init (&btrace);
7159 err = linux_read_btrace (&btrace, tinfo, type);
7160 if (err != BTRACE_ERR_NONE)
7162 if (err == BTRACE_ERR_OVERFLOW)
7163 buffer_grow_str0 (buffer, "E.Overflow.");
7165 buffer_grow_str0 (buffer, "E.Generic Error.");
7170 switch (btrace.format)
7172 case BTRACE_FORMAT_NONE:
7173 buffer_grow_str0 (buffer, "E.No Trace.");
7176 case BTRACE_FORMAT_BTS:
7177 buffer_grow_str (buffer, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
7178 buffer_grow_str (buffer, "<btrace version=\"1.0\">\n");
7181 VEC_iterate (btrace_block_s, btrace.variant.bts.blocks, i, block);
7183 buffer_xml_printf (buffer, "<block begin=\"0x%s\" end=\"0x%s\"/>\n",
7184 paddress (block->begin), paddress (block->end));
7186 buffer_grow_str0 (buffer, "</btrace>\n");
7189 case BTRACE_FORMAT_PT:
7190 buffer_grow_str (buffer, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
7191 buffer_grow_str (buffer, "<btrace version=\"1.0\">\n");
7192 buffer_grow_str (buffer, "<pt>\n");
7194 linux_low_encode_pt_config (buffer, &btrace.variant.pt.config);
7196 linux_low_encode_raw (buffer, btrace.variant.pt.data,
7197 btrace.variant.pt.size);
7199 buffer_grow_str (buffer, "</pt>\n");
7200 buffer_grow_str0 (buffer, "</btrace>\n");
7204 buffer_grow_str0 (buffer, "E.Unsupported Trace Format.");
7208 btrace_data_fini (&btrace);
7212 btrace_data_fini (&btrace);
7216 /* See to_btrace_conf target method. */
7219 linux_low_btrace_conf (const struct btrace_target_info *tinfo,
7220 struct buffer *buffer)
7222 const struct btrace_config *conf;
7224 buffer_grow_str (buffer, "<!DOCTYPE btrace-conf SYSTEM \"btrace-conf.dtd\">\n");
7225 buffer_grow_str (buffer, "<btrace-conf version=\"1.0\">\n");
7227 conf = linux_btrace_conf (tinfo);
7230 switch (conf->format)
7232 case BTRACE_FORMAT_NONE:
7235 case BTRACE_FORMAT_BTS:
7236 buffer_xml_printf (buffer, "<bts");
7237 buffer_xml_printf (buffer, " size=\"0x%x\"", conf->bts.size);
7238 buffer_xml_printf (buffer, " />\n");
7241 case BTRACE_FORMAT_PT:
7242 buffer_xml_printf (buffer, "<pt");
7243 buffer_xml_printf (buffer, " size=\"0x%x\"", conf->pt.size);
7244 buffer_xml_printf (buffer, "/>\n");
7249 buffer_grow_str0 (buffer, "</btrace-conf>\n");
7252 #endif /* HAVE_LINUX_BTRACE */
7254 /* See nat/linux-nat.h. */
7257 current_lwp_ptid (void)
7259 return ptid_of (current_thread);
7262 /* Implementation of the target_ops method "breakpoint_kind_from_pc". */
7265 linux_breakpoint_kind_from_pc (CORE_ADDR *pcptr)
7267 if (the_low_target.breakpoint_kind_from_pc != NULL)
7268 return (*the_low_target.breakpoint_kind_from_pc) (pcptr);
7270 return default_breakpoint_kind_from_pc (pcptr);
7273 /* Implementation of the target_ops method "sw_breakpoint_from_kind". */
7275 static const gdb_byte *
7276 linux_sw_breakpoint_from_kind (int kind, int *size)
7278 gdb_assert (the_low_target.sw_breakpoint_from_kind != NULL);
7280 return (*the_low_target.sw_breakpoint_from_kind) (kind, size);
7283 /* Implementation of the target_ops method
7284 "breakpoint_kind_from_current_state". */
7287 linux_breakpoint_kind_from_current_state (CORE_ADDR *pcptr)
7289 if (the_low_target.breakpoint_kind_from_current_state != NULL)
7290 return (*the_low_target.breakpoint_kind_from_current_state) (pcptr);
7292 return linux_breakpoint_kind_from_pc (pcptr);
7295 /* Default implementation of linux_target_ops method "set_pc" for
7296 32-bit pc register which is literally named "pc". */
7299 linux_set_pc_32bit (struct regcache *regcache, CORE_ADDR pc)
7301 uint32_t newpc = pc;
7303 supply_register_by_name (regcache, "pc", &newpc);
7306 /* Default implementation of linux_target_ops method "get_pc" for
7307 32-bit pc register which is literally named "pc". */
7310 linux_get_pc_32bit (struct regcache *regcache)
7314 collect_register_by_name (regcache, "pc", &pc);
7316 debug_printf ("stop pc is 0x%" PRIx32 "\n", pc);
7320 /* Default implementation of linux_target_ops method "set_pc" for
7321 64-bit pc register which is literally named "pc". */
7324 linux_set_pc_64bit (struct regcache *regcache, CORE_ADDR pc)
7326 uint64_t newpc = pc;
7328 supply_register_by_name (regcache, "pc", &newpc);
7331 /* Default implementation of linux_target_ops method "get_pc" for
7332 64-bit pc register which is literally named "pc". */
7335 linux_get_pc_64bit (struct regcache *regcache)
7339 collect_register_by_name (regcache, "pc", &pc);
7341 debug_printf ("stop pc is 0x%" PRIx64 "\n", pc);
7346 static struct target_ops linux_target_ops = {
7347 linux_create_inferior,
7348 linux_post_create_inferior,
7357 linux_fetch_registers,
7358 linux_store_registers,
7359 linux_prepare_to_access_memory,
7360 linux_done_accessing_memory,
7363 linux_look_up_symbols,
7364 linux_request_interrupt,
7366 linux_supports_z_point_type,
7369 linux_stopped_by_sw_breakpoint,
7370 linux_supports_stopped_by_sw_breakpoint,
7371 linux_stopped_by_hw_breakpoint,
7372 linux_supports_stopped_by_hw_breakpoint,
7373 linux_supports_hardware_single_step,
7374 linux_stopped_by_watchpoint,
7375 linux_stopped_data_address,
7376 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
7377 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
7378 && defined(PT_TEXT_END_ADDR)
7383 #ifdef USE_THREAD_DB
7384 thread_db_get_tls_address,
7389 hostio_last_error_from_errno,
7392 linux_supports_non_stop,
7394 linux_start_non_stop,
7395 linux_supports_multi_process,
7396 linux_supports_fork_events,
7397 linux_supports_vfork_events,
7398 linux_supports_exec_events,
7399 linux_handle_new_gdb_connection,
7400 #ifdef USE_THREAD_DB
7401 thread_db_handle_monitor_command,
7405 linux_common_core_of_thread,
7407 linux_process_qsupported,
7408 linux_supports_tracepoints,
7411 linux_thread_stopped,
7415 linux_stabilize_threads,
7416 linux_install_fast_tracepoint_jump_pad,
7418 linux_supports_disable_randomization,
7419 linux_get_min_fast_tracepoint_insn_len,
7420 linux_qxfer_libraries_svr4,
7421 linux_supports_agent,
7422 #ifdef HAVE_LINUX_BTRACE
7423 linux_supports_btrace,
7424 linux_enable_btrace,
7425 linux_low_disable_btrace,
7426 linux_low_read_btrace,
7427 linux_low_btrace_conf,
7435 linux_supports_range_stepping,
7436 linux_proc_pid_to_exec_file,
7437 linux_mntns_open_cloexec,
7439 linux_mntns_readlink,
7440 linux_breakpoint_kind_from_pc,
7441 linux_sw_breakpoint_from_kind,
7442 linux_proc_tid_get_name,
7443 linux_breakpoint_kind_from_current_state,
7444 linux_supports_software_single_step,
7445 linux_supports_catch_syscall,
7446 linux_get_ipa_tdesc_idx,
7449 #ifdef HAVE_LINUX_REGSETS
7451 initialize_regsets_info (struct regsets_info *info)
7453 for (info->num_regsets = 0;
7454 info->regsets[info->num_regsets].size >= 0;
7455 info->num_regsets++)
7461 initialize_low (void)
7463 struct sigaction sigchld_action;
7465 memset (&sigchld_action, 0, sizeof (sigchld_action));
7466 set_target_ops (&linux_target_ops);
7468 linux_ptrace_init_warnings ();
7470 sigchld_action.sa_handler = sigchld_handler;
7471 sigemptyset (&sigchld_action.sa_mask);
7472 sigchld_action.sa_flags = SA_RESTART;
7473 sigaction (SIGCHLD, &sigchld_action, NULL);
7475 initialize_low_arch ();
7477 linux_check_ptrace_features ();