1 /* Low level interface to ptrace, for the remote server for GDB.
2 Copyright (C) 1995-2015 Free Software Foundation, Inc.
4 This file is part of GDB.
6 This program is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>. */
20 #include "linux-low.h"
21 #include "nat/linux-osdata.h"
24 #include "nat/linux-nat.h"
25 #include "nat/linux-waitpid.h"
27 #include <sys/ptrace.h>
28 #include "nat/linux-ptrace.h"
29 #include "nat/linux-procfs.h"
30 #include "nat/linux-personality.h"
32 #include <sys/ioctl.h>
35 #include <sys/syscall.h>
39 #include <sys/types.h>
44 #include "filestuff.h"
45 #include "tracepoint.h"
48 /* Don't include <linux/elf.h> here. If it got included by gdb_proc_service.h
49 then ELFMAG0 will have been defined. If it didn't get included by
50 gdb_proc_service.h then including it will likely introduce a duplicate
51 definition of elf_fpregset_t. */
56 #define SPUFS_MAGIC 0x23c9b64e
59 #ifdef HAVE_PERSONALITY
60 # include <sys/personality.h>
61 # if !HAVE_DECL_ADDR_NO_RANDOMIZE
62 # define ADDR_NO_RANDOMIZE 0x0040000
71 #define W_STOPCODE(sig) ((sig) << 8 | 0x7f)
74 /* This is the kernel's hard limit. Not to be confused with
80 /* Some targets did not define these ptrace constants from the start,
81 so gdbserver defines them locally here. In the future, these may
82 be removed after they are added to asm/ptrace.h. */
83 #if !(defined(PT_TEXT_ADDR) \
84 || defined(PT_DATA_ADDR) \
85 || defined(PT_TEXT_END_ADDR))
86 #if defined(__mcoldfire__)
87 /* These are still undefined in 3.10 kernels. */
88 #define PT_TEXT_ADDR 49*4
89 #define PT_DATA_ADDR 50*4
90 #define PT_TEXT_END_ADDR 51*4
91 /* BFIN already defines these since at least 2.6.32 kernels. */
93 #define PT_TEXT_ADDR 220
94 #define PT_TEXT_END_ADDR 224
95 #define PT_DATA_ADDR 228
96 /* These are still undefined in 3.10 kernels. */
97 #elif defined(__TMS320C6X__)
98 #define PT_TEXT_ADDR (0x10000*4)
99 #define PT_DATA_ADDR (0x10004*4)
100 #define PT_TEXT_END_ADDR (0x10008*4)
104 #ifdef HAVE_LINUX_BTRACE
105 # include "nat/linux-btrace.h"
106 # include "btrace-common.h"
109 #ifndef HAVE_ELF32_AUXV_T
110 /* Copied from glibc's elf.h. */
113 uint32_t a_type; /* Entry type */
116 uint32_t a_val; /* Integer value */
117 /* We use to have pointer elements added here. We cannot do that,
118 though, since it does not work when using 32-bit definitions
119 on 64-bit platforms and vice versa. */
124 #ifndef HAVE_ELF64_AUXV_T
125 /* Copied from glibc's elf.h. */
128 uint64_t a_type; /* Entry type */
131 uint64_t a_val; /* Integer value */
132 /* We use to have pointer elements added here. We cannot do that,
133 though, since it does not work when using 32-bit definitions
134 on 64-bit platforms and vice versa. */
139 /* A list of all unknown processes which receive stop signals. Some
140 other process will presumably claim each of these as forked
141 children momentarily. */
143 struct simple_pid_list
145 /* The process ID. */
148 /* The status as reported by waitpid. */
152 struct simple_pid_list *next;
154 struct simple_pid_list *stopped_pids;
156 /* Trivial list manipulation functions to keep track of a list of new
157 stopped processes. */
160 add_to_pid_list (struct simple_pid_list **listp, int pid, int status)
162 struct simple_pid_list *new_pid = xmalloc (sizeof (struct simple_pid_list));
165 new_pid->status = status;
166 new_pid->next = *listp;
171 pull_pid_from_list (struct simple_pid_list **listp, int pid, int *statusp)
173 struct simple_pid_list **p;
175 for (p = listp; *p != NULL; p = &(*p)->next)
176 if ((*p)->pid == pid)
178 struct simple_pid_list *next = (*p)->next;
180 *statusp = (*p)->status;
188 enum stopping_threads_kind
190 /* Not stopping threads presently. */
191 NOT_STOPPING_THREADS,
193 /* Stopping threads. */
196 /* Stopping and suspending threads. */
197 STOPPING_AND_SUSPENDING_THREADS
200 /* This is set while stop_all_lwps is in effect. */
201 enum stopping_threads_kind stopping_threads = NOT_STOPPING_THREADS;
203 /* FIXME make into a target method? */
204 int using_threads = 1;
206 /* True if we're presently stabilizing threads (moving them out of
208 static int stabilizing_threads;
210 static void linux_resume_one_lwp (struct lwp_info *lwp,
211 int step, int signal, siginfo_t *info);
212 static void linux_resume (struct thread_resume *resume_info, size_t n);
213 static void stop_all_lwps (int suspend, struct lwp_info *except);
214 static void unstop_all_lwps (int unsuspend, struct lwp_info *except);
215 static int linux_wait_for_event_filtered (ptid_t wait_ptid, ptid_t filter_ptid,
216 int *wstat, int options);
217 static int linux_wait_for_event (ptid_t ptid, int *wstat, int options);
218 static struct lwp_info *add_lwp (ptid_t ptid);
219 static int linux_stopped_by_watchpoint (void);
220 static void mark_lwp_dead (struct lwp_info *lwp, int wstat);
221 static void proceed_all_lwps (void);
222 static int finish_step_over (struct lwp_info *lwp);
223 static int kill_lwp (unsigned long lwpid, int signo);
225 /* When the event-loop is doing a step-over, this points at the thread
227 ptid_t step_over_bkpt;
229 /* True if the low target can hardware single-step. Such targets
230 don't need a BREAKPOINT_REINSERT_ADDR callback. */
233 can_hardware_single_step (void)
235 return (the_low_target.breakpoint_reinsert_addr == NULL);
238 /* True if the low target supports memory breakpoints. If so, we'll
239 have a GET_PC implementation. */
242 supports_breakpoints (void)
244 return (the_low_target.get_pc != NULL);
247 /* Returns true if this target can support fast tracepoints. This
248 does not mean that the in-process agent has been loaded in the
252 supports_fast_tracepoints (void)
254 return the_low_target.install_fast_tracepoint_jump_pad != NULL;
257 /* True if LWP is stopped in its stepping range. */
260 lwp_in_step_range (struct lwp_info *lwp)
262 CORE_ADDR pc = lwp->stop_pc;
264 return (pc >= lwp->step_range_start && pc < lwp->step_range_end);
267 struct pending_signals
271 struct pending_signals *prev;
274 /* The read/write ends of the pipe registered as waitable file in the
276 static int linux_event_pipe[2] = { -1, -1 };
278 /* True if we're currently in async mode. */
279 #define target_is_async_p() (linux_event_pipe[0] != -1)
281 static void send_sigstop (struct lwp_info *lwp);
282 static void wait_for_sigstop (void);
284 /* Return non-zero if HEADER is a 64-bit ELF file. */
287 elf_64_header_p (const Elf64_Ehdr *header, unsigned int *machine)
289 if (header->e_ident[EI_MAG0] == ELFMAG0
290 && header->e_ident[EI_MAG1] == ELFMAG1
291 && header->e_ident[EI_MAG2] == ELFMAG2
292 && header->e_ident[EI_MAG3] == ELFMAG3)
294 *machine = header->e_machine;
295 return header->e_ident[EI_CLASS] == ELFCLASS64;
302 /* Return non-zero if FILE is a 64-bit ELF file,
303 zero if the file is not a 64-bit ELF file,
304 and -1 if the file is not accessible or doesn't exist. */
307 elf_64_file_p (const char *file, unsigned int *machine)
312 fd = open (file, O_RDONLY);
316 if (read (fd, &header, sizeof (header)) != sizeof (header))
323 return elf_64_header_p (&header, machine);
326 /* Accepts an integer PID; Returns true if the executable PID is
327 running is a 64-bit ELF file.. */
330 linux_pid_exe_is_elf_64_file (int pid, unsigned int *machine)
334 sprintf (file, "/proc/%d/exe", pid);
335 return elf_64_file_p (file, machine);
339 delete_lwp (struct lwp_info *lwp)
341 struct thread_info *thr = get_lwp_thread (lwp);
344 debug_printf ("deleting %ld\n", lwpid_of (thr));
347 free (lwp->arch_private);
351 /* Add a process to the common process list, and set its private
354 static struct process_info *
355 linux_add_process (int pid, int attached)
357 struct process_info *proc;
359 proc = add_process (pid, attached);
360 proc->private = xcalloc (1, sizeof (*proc->private));
362 /* Set the arch when the first LWP stops. */
363 proc->private->new_inferior = 1;
365 if (the_low_target.new_process != NULL)
366 proc->private->arch_private = the_low_target.new_process ();
371 static CORE_ADDR get_pc (struct lwp_info *lwp);
373 /* Handle a GNU/Linux extended wait response. If we see a clone
374 event, we need to add the new LWP to our list (and not report the
375 trap to higher layers). */
378 handle_extended_wait (struct lwp_info *event_child, int wstat)
380 int event = linux_ptrace_get_extended_event (wstat);
381 struct thread_info *event_thr = get_lwp_thread (event_child);
382 struct lwp_info *new_lwp;
384 if (event == PTRACE_EVENT_CLONE)
387 unsigned long new_pid;
390 ptrace (PTRACE_GETEVENTMSG, lwpid_of (event_thr), (PTRACE_TYPE_ARG3) 0,
393 /* If we haven't already seen the new PID stop, wait for it now. */
394 if (!pull_pid_from_list (&stopped_pids, new_pid, &status))
396 /* The new child has a pending SIGSTOP. We can't affect it until it
397 hits the SIGSTOP, but we're already attached. */
399 ret = my_waitpid (new_pid, &status, __WALL);
402 perror_with_name ("waiting for new child");
403 else if (ret != new_pid)
404 warning ("wait returned unexpected PID %d", ret);
405 else if (!WIFSTOPPED (status))
406 warning ("wait returned unexpected status 0x%x", status);
410 debug_printf ("HEW: Got clone event "
411 "from LWP %ld, new child is LWP %ld\n",
412 lwpid_of (event_thr), new_pid);
414 ptid = ptid_build (pid_of (event_thr), new_pid, 0);
415 new_lwp = add_lwp (ptid);
417 /* Either we're going to immediately resume the new thread
418 or leave it stopped. linux_resume_one_lwp is a nop if it
419 thinks the thread is currently running, so set this first
420 before calling linux_resume_one_lwp. */
421 new_lwp->stopped = 1;
423 /* If we're suspending all threads, leave this one suspended
425 if (stopping_threads == STOPPING_AND_SUSPENDING_THREADS)
426 new_lwp->suspended = 1;
428 /* Normally we will get the pending SIGSTOP. But in some cases
429 we might get another signal delivered to the group first.
430 If we do get another signal, be sure not to lose it. */
431 if (WSTOPSIG (status) != SIGSTOP)
433 new_lwp->stop_expected = 1;
434 new_lwp->status_pending_p = 1;
435 new_lwp->status_pending = status;
440 /* Return the PC as read from the regcache of LWP, without any
444 get_pc (struct lwp_info *lwp)
446 struct thread_info *saved_thread;
447 struct regcache *regcache;
450 if (the_low_target.get_pc == NULL)
453 saved_thread = current_thread;
454 current_thread = get_lwp_thread (lwp);
456 regcache = get_thread_regcache (current_thread, 1);
457 pc = (*the_low_target.get_pc) (regcache);
460 debug_printf ("pc is 0x%lx\n", (long) pc);
462 current_thread = saved_thread;
466 /* This function should only be called if LWP got a SIGTRAP.
467 The SIGTRAP could mean several things.
469 On i386, where decr_pc_after_break is non-zero:
471 If we were single-stepping this process using PTRACE_SINGLESTEP, we
472 will get only the one SIGTRAP. The value of $eip will be the next
473 instruction. If the instruction we stepped over was a breakpoint,
474 we need to decrement the PC.
476 If we continue the process using PTRACE_CONT, we will get a
477 SIGTRAP when we hit a breakpoint. The value of $eip will be
478 the instruction after the breakpoint (i.e. needs to be
479 decremented). If we report the SIGTRAP to GDB, we must also
480 report the undecremented PC. If the breakpoint is removed, we
481 must resume at the decremented PC.
483 On a non-decr_pc_after_break machine with hardware or kernel
486 If we either single-step a breakpoint instruction, or continue and
487 hit a breakpoint instruction, our PC will point at the breakpoint
491 check_stopped_by_breakpoint (struct lwp_info *lwp)
494 CORE_ADDR sw_breakpoint_pc;
495 struct thread_info *saved_thread;
497 if (the_low_target.get_pc == NULL)
501 sw_breakpoint_pc = pc - the_low_target.decr_pc_after_break;
503 /* breakpoint_at reads from the current thread. */
504 saved_thread = current_thread;
505 current_thread = get_lwp_thread (lwp);
507 /* We may have just stepped a breakpoint instruction. E.g., in
508 non-stop mode, GDB first tells the thread A to step a range, and
509 then the user inserts a breakpoint inside the range. In that
510 case we need to report the breakpoint PC. */
511 if ((!lwp->stepping || lwp->stop_pc == sw_breakpoint_pc)
512 && (*the_low_target.breakpoint_at) (sw_breakpoint_pc))
516 struct thread_info *thr = get_lwp_thread (lwp);
518 debug_printf ("CSBB: %s stopped by software breakpoint\n",
519 target_pid_to_str (ptid_of (thr)));
522 /* Back up the PC if necessary. */
523 if (pc != sw_breakpoint_pc)
525 struct regcache *regcache
526 = get_thread_regcache (current_thread, 1);
527 (*the_low_target.set_pc) (regcache, sw_breakpoint_pc);
530 lwp->stop_pc = sw_breakpoint_pc;
531 lwp->stop_reason = LWP_STOPPED_BY_SW_BREAKPOINT;
532 current_thread = saved_thread;
536 if (hardware_breakpoint_inserted_here (pc))
540 struct thread_info *thr = get_lwp_thread (lwp);
542 debug_printf ("CSBB: %s stopped by hardware breakpoint\n",
543 target_pid_to_str (ptid_of (thr)));
547 lwp->stop_reason = LWP_STOPPED_BY_HW_BREAKPOINT;
548 current_thread = saved_thread;
552 current_thread = saved_thread;
556 static struct lwp_info *
557 add_lwp (ptid_t ptid)
559 struct lwp_info *lwp;
561 lwp = (struct lwp_info *) xmalloc (sizeof (*lwp));
562 memset (lwp, 0, sizeof (*lwp));
564 if (the_low_target.new_thread != NULL)
565 lwp->arch_private = the_low_target.new_thread ();
567 lwp->thread = add_thread (ptid, lwp);
572 /* Start an inferior process and returns its pid.
573 ALLARGS is a vector of program-name and args. */
576 linux_create_inferior (char *program, char **allargs)
578 struct lwp_info *new_lwp;
581 struct cleanup *restore_personality
582 = maybe_disable_address_space_randomization (disable_randomization);
584 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
590 perror_with_name ("fork");
595 ptrace (PTRACE_TRACEME, 0, (PTRACE_TYPE_ARG3) 0, (PTRACE_TYPE_ARG4) 0);
597 #ifndef __ANDROID__ /* Bionic doesn't use SIGRTMIN the way glibc does. */
598 signal (__SIGRTMIN + 1, SIG_DFL);
603 /* If gdbserver is connected to gdb via stdio, redirect the inferior's
604 stdout to stderr so that inferior i/o doesn't corrupt the connection.
605 Also, redirect stdin to /dev/null. */
606 if (remote_connection_is_stdio ())
609 open ("/dev/null", O_RDONLY);
611 if (write (2, "stdin/stdout redirected\n",
612 sizeof ("stdin/stdout redirected\n") - 1) < 0)
614 /* Errors ignored. */;
618 execv (program, allargs);
620 execvp (program, allargs);
622 fprintf (stderr, "Cannot exec %s: %s.\n", program,
628 do_cleanups (restore_personality);
630 linux_add_process (pid, 0);
632 ptid = ptid_build (pid, pid, 0);
633 new_lwp = add_lwp (ptid);
634 new_lwp->must_set_ptrace_flags = 1;
639 /* Attach to an inferior process. Returns 0 on success, ERRNO on
643 linux_attach_lwp (ptid_t ptid)
645 struct lwp_info *new_lwp;
646 int lwpid = ptid_get_lwp (ptid);
648 if (ptrace (PTRACE_ATTACH, lwpid, (PTRACE_TYPE_ARG3) 0, (PTRACE_TYPE_ARG4) 0)
652 new_lwp = add_lwp (ptid);
654 /* We need to wait for SIGSTOP before being able to make the next
655 ptrace call on this LWP. */
656 new_lwp->must_set_ptrace_flags = 1;
658 if (linux_proc_pid_is_stopped (lwpid))
661 debug_printf ("Attached to a stopped process\n");
663 /* The process is definitely stopped. It is in a job control
664 stop, unless the kernel predates the TASK_STOPPED /
665 TASK_TRACED distinction, in which case it might be in a
666 ptrace stop. Make sure it is in a ptrace stop; from there we
667 can kill it, signal it, et cetera.
669 First make sure there is a pending SIGSTOP. Since we are
670 already attached, the process can not transition from stopped
671 to running without a PTRACE_CONT; so we know this signal will
672 go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
673 probably already in the queue (unless this kernel is old
674 enough to use TASK_STOPPED for ptrace stops); but since
675 SIGSTOP is not an RT signal, it can only be queued once. */
676 kill_lwp (lwpid, SIGSTOP);
678 /* Finally, resume the stopped process. This will deliver the
679 SIGSTOP (or a higher priority signal, just like normal
680 PTRACE_ATTACH), which we'll catch later on. */
681 ptrace (PTRACE_CONT, lwpid, (PTRACE_TYPE_ARG3) 0, (PTRACE_TYPE_ARG4) 0);
684 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
687 There are several cases to consider here:
689 1) gdbserver has already attached to the process and is being notified
690 of a new thread that is being created.
691 In this case we should ignore that SIGSTOP and resume the
692 process. This is handled below by setting stop_expected = 1,
693 and the fact that add_thread sets last_resume_kind ==
696 2) This is the first thread (the process thread), and we're attaching
697 to it via attach_inferior.
698 In this case we want the process thread to stop.
699 This is handled by having linux_attach set last_resume_kind ==
700 resume_stop after we return.
702 If the pid we are attaching to is also the tgid, we attach to and
703 stop all the existing threads. Otherwise, we attach to pid and
704 ignore any other threads in the same group as this pid.
706 3) GDB is connecting to gdbserver and is requesting an enumeration of all
708 In this case we want the thread to stop.
709 FIXME: This case is currently not properly handled.
710 We should wait for the SIGSTOP but don't. Things work apparently
711 because enough time passes between when we ptrace (ATTACH) and when
712 gdb makes the next ptrace call on the thread.
714 On the other hand, if we are currently trying to stop all threads, we
715 should treat the new thread as if we had sent it a SIGSTOP. This works
716 because we are guaranteed that the add_lwp call above added us to the
717 end of the list, and so the new thread has not yet reached
718 wait_for_sigstop (but will). */
719 new_lwp->stop_expected = 1;
724 /* Callback for linux_proc_attach_tgid_threads. Attach to PTID if not
725 already attached. Returns true if a new LWP is found, false
729 attach_proc_task_lwp_callback (ptid_t ptid)
731 /* Is this a new thread? */
732 if (find_thread_ptid (ptid) == NULL)
734 int lwpid = ptid_get_lwp (ptid);
738 debug_printf ("Found new lwp %d\n", lwpid);
740 err = linux_attach_lwp (ptid);
742 /* Be quiet if we simply raced with the thread exiting. EPERM
743 is returned if the thread's task still exists, and is marked
744 as exited or zombie, as well as other conditions, so in that
745 case, confirm the status in /proc/PID/status. */
747 || (err == EPERM && linux_proc_pid_is_gone (lwpid)))
751 debug_printf ("Cannot attach to lwp %d: "
752 "thread is gone (%d: %s)\n",
753 lwpid, err, strerror (err));
758 warning (_("Cannot attach to lwp %d: %s"),
760 linux_ptrace_attach_fail_reason_string (ptid, err));
768 /* Attach to PID. If PID is the tgid, attach to it and all
772 linux_attach (unsigned long pid)
774 ptid_t ptid = ptid_build (pid, pid, 0);
777 /* Attach to PID. We will check for other threads
779 err = linux_attach_lwp (ptid);
781 error ("Cannot attach to process %ld: %s",
782 pid, linux_ptrace_attach_fail_reason_string (ptid, err));
784 linux_add_process (pid, 1);
788 struct thread_info *thread;
790 /* Don't ignore the initial SIGSTOP if we just attached to this
791 process. It will be collected by wait shortly. */
792 thread = find_thread_ptid (ptid_build (pid, pid, 0));
793 thread->last_resume_kind = resume_stop;
796 /* We must attach to every LWP. If /proc is mounted, use that to
797 find them now. On the one hand, the inferior may be using raw
798 clone instead of using pthreads. On the other hand, even if it
799 is using pthreads, GDB may not be connected yet (thread_db needs
800 to do symbol lookups, through qSymbol). Also, thread_db walks
801 structures in the inferior's address space to find the list of
802 threads/LWPs, and those structures may well be corrupted. Note
803 that once thread_db is loaded, we'll still use it to list threads
804 and associate pthread info with each LWP. */
805 linux_proc_attach_tgid_threads (pid, attach_proc_task_lwp_callback);
816 second_thread_of_pid_p (struct inferior_list_entry *entry, void *args)
818 struct counter *counter = args;
820 if (ptid_get_pid (entry->id) == counter->pid)
822 if (++counter->count > 1)
830 last_thread_of_process_p (int pid)
832 struct counter counter = { pid , 0 };
834 return (find_inferior (&all_threads,
835 second_thread_of_pid_p, &counter) == NULL);
841 linux_kill_one_lwp (struct lwp_info *lwp)
843 struct thread_info *thr = get_lwp_thread (lwp);
844 int pid = lwpid_of (thr);
846 /* PTRACE_KILL is unreliable. After stepping into a signal handler,
847 there is no signal context, and ptrace(PTRACE_KILL) (or
848 ptrace(PTRACE_CONT, SIGKILL), pretty much the same) acts like
849 ptrace(CONT, pid, 0,0) and just resumes the tracee. A better
850 alternative is to kill with SIGKILL. We only need one SIGKILL
851 per process, not one for each thread. But since we still support
852 linuxthreads, and we also support debugging programs using raw
853 clone without CLONE_THREAD, we send one for each thread. For
854 years, we used PTRACE_KILL only, so we're being a bit paranoid
855 about some old kernels where PTRACE_KILL might work better
856 (dubious if there are any such, but that's why it's paranoia), so
857 we try SIGKILL first, PTRACE_KILL second, and so we're fine
861 kill_lwp (pid, SIGKILL);
864 int save_errno = errno;
866 debug_printf ("LKL: kill_lwp (SIGKILL) %s, 0, 0 (%s)\n",
867 target_pid_to_str (ptid_of (thr)),
868 save_errno ? strerror (save_errno) : "OK");
872 ptrace (PTRACE_KILL, pid, (PTRACE_TYPE_ARG3) 0, (PTRACE_TYPE_ARG4) 0);
875 int save_errno = errno;
877 debug_printf ("LKL: PTRACE_KILL %s, 0, 0 (%s)\n",
878 target_pid_to_str (ptid_of (thr)),
879 save_errno ? strerror (save_errno) : "OK");
883 /* Kill LWP and wait for it to die. */
886 kill_wait_lwp (struct lwp_info *lwp)
888 struct thread_info *thr = get_lwp_thread (lwp);
889 int pid = ptid_get_pid (ptid_of (thr));
890 int lwpid = ptid_get_lwp (ptid_of (thr));
895 debug_printf ("kwl: killing lwp %d, for pid: %d\n", lwpid, pid);
899 linux_kill_one_lwp (lwp);
901 /* Make sure it died. Notes:
903 - The loop is most likely unnecessary.
905 - We don't use linux_wait_for_event as that could delete lwps
906 while we're iterating over them. We're not interested in
907 any pending status at this point, only in making sure all
908 wait status on the kernel side are collected until the
911 - We don't use __WALL here as the __WALL emulation relies on
912 SIGCHLD, and killing a stopped process doesn't generate
913 one, nor an exit status.
915 res = my_waitpid (lwpid, &wstat, 0);
916 if (res == -1 && errno == ECHILD)
917 res = my_waitpid (lwpid, &wstat, __WCLONE);
918 } while (res > 0 && WIFSTOPPED (wstat));
920 gdb_assert (res > 0);
923 /* Callback for `find_inferior'. Kills an lwp of a given process,
924 except the leader. */
927 kill_one_lwp_callback (struct inferior_list_entry *entry, void *args)
929 struct thread_info *thread = (struct thread_info *) entry;
930 struct lwp_info *lwp = get_thread_lwp (thread);
931 int pid = * (int *) args;
933 if (ptid_get_pid (entry->id) != pid)
936 /* We avoid killing the first thread here, because of a Linux kernel (at
937 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
938 the children get a chance to be reaped, it will remain a zombie
941 if (lwpid_of (thread) == pid)
944 debug_printf ("lkop: is last of process %s\n",
945 target_pid_to_str (entry->id));
956 struct process_info *process;
957 struct lwp_info *lwp;
959 process = find_process_pid (pid);
963 /* If we're killing a running inferior, make sure it is stopped
964 first, as PTRACE_KILL will not work otherwise. */
965 stop_all_lwps (0, NULL);
967 find_inferior (&all_threads, kill_one_lwp_callback , &pid);
969 /* See the comment in linux_kill_one_lwp. We did not kill the first
970 thread in the list, so do so now. */
971 lwp = find_lwp_pid (pid_to_ptid (pid));
976 debug_printf ("lk_1: cannot find lwp for pid: %d\n",
982 the_target->mourn (process);
984 /* Since we presently can only stop all lwps of all processes, we
985 need to unstop lwps of other processes. */
986 unstop_all_lwps (0, NULL);
990 /* Get pending signal of THREAD, for detaching purposes. This is the
991 signal the thread last stopped for, which we need to deliver to the
992 thread when detaching, otherwise, it'd be suppressed/lost. */
995 get_detach_signal (struct thread_info *thread)
997 enum gdb_signal signo = GDB_SIGNAL_0;
999 struct lwp_info *lp = get_thread_lwp (thread);
1001 if (lp->status_pending_p)
1002 status = lp->status_pending;
1005 /* If the thread had been suspended by gdbserver, and it stopped
1006 cleanly, then it'll have stopped with SIGSTOP. But we don't
1007 want to deliver that SIGSTOP. */
1008 if (thread->last_status.kind != TARGET_WAITKIND_STOPPED
1009 || thread->last_status.value.sig == GDB_SIGNAL_0)
1012 /* Otherwise, we may need to deliver the signal we
1014 status = lp->last_status;
1017 if (!WIFSTOPPED (status))
1020 debug_printf ("GPS: lwp %s hasn't stopped: no pending signal\n",
1021 target_pid_to_str (ptid_of (thread)));
1025 /* Extended wait statuses aren't real SIGTRAPs. */
1026 if (WSTOPSIG (status) == SIGTRAP && linux_is_extended_waitstatus (status))
1029 debug_printf ("GPS: lwp %s had stopped with extended "
1030 "status: no pending signal\n",
1031 target_pid_to_str (ptid_of (thread)));
1035 signo = gdb_signal_from_host (WSTOPSIG (status));
1037 if (program_signals_p && !program_signals[signo])
1040 debug_printf ("GPS: lwp %s had signal %s, but it is in nopass state\n",
1041 target_pid_to_str (ptid_of (thread)),
1042 gdb_signal_to_string (signo));
1045 else if (!program_signals_p
1046 /* If we have no way to know which signals GDB does not
1047 want to have passed to the program, assume
1048 SIGTRAP/SIGINT, which is GDB's default. */
1049 && (signo == GDB_SIGNAL_TRAP || signo == GDB_SIGNAL_INT))
1052 debug_printf ("GPS: lwp %s had signal %s, "
1053 "but we don't know if we should pass it. "
1054 "Default to not.\n",
1055 target_pid_to_str (ptid_of (thread)),
1056 gdb_signal_to_string (signo));
1062 debug_printf ("GPS: lwp %s has pending signal %s: delivering it.\n",
1063 target_pid_to_str (ptid_of (thread)),
1064 gdb_signal_to_string (signo));
1066 return WSTOPSIG (status);
1071 linux_detach_one_lwp (struct inferior_list_entry *entry, void *args)
1073 struct thread_info *thread = (struct thread_info *) entry;
1074 struct lwp_info *lwp = get_thread_lwp (thread);
1075 int pid = * (int *) args;
1078 if (ptid_get_pid (entry->id) != pid)
1081 /* If there is a pending SIGSTOP, get rid of it. */
1082 if (lwp->stop_expected)
1085 debug_printf ("Sending SIGCONT to %s\n",
1086 target_pid_to_str (ptid_of (thread)));
1088 kill_lwp (lwpid_of (thread), SIGCONT);
1089 lwp->stop_expected = 0;
1092 /* Flush any pending changes to the process's registers. */
1093 regcache_invalidate_thread (thread);
1095 /* Pass on any pending signal for this thread. */
1096 sig = get_detach_signal (thread);
1098 /* Finally, let it resume. */
1099 if (the_low_target.prepare_to_resume != NULL)
1100 the_low_target.prepare_to_resume (lwp);
1101 if (ptrace (PTRACE_DETACH, lwpid_of (thread), (PTRACE_TYPE_ARG3) 0,
1102 (PTRACE_TYPE_ARG4) (long) sig) < 0)
1103 error (_("Can't detach %s: %s"),
1104 target_pid_to_str (ptid_of (thread)),
1112 linux_detach (int pid)
1114 struct process_info *process;
1116 process = find_process_pid (pid);
1117 if (process == NULL)
1120 /* Stop all threads before detaching. First, ptrace requires that
1121 the thread is stopped to sucessfully detach. Second, thread_db
1122 may need to uninstall thread event breakpoints from memory, which
1123 only works with a stopped process anyway. */
1124 stop_all_lwps (0, NULL);
1126 #ifdef USE_THREAD_DB
1127 thread_db_detach (process);
1130 /* Stabilize threads (move out of jump pads). */
1131 stabilize_threads ();
1133 find_inferior (&all_threads, linux_detach_one_lwp, &pid);
1135 the_target->mourn (process);
1137 /* Since we presently can only stop all lwps of all processes, we
1138 need to unstop lwps of other processes. */
1139 unstop_all_lwps (0, NULL);
1143 /* Remove all LWPs that belong to process PROC from the lwp list. */
1146 delete_lwp_callback (struct inferior_list_entry *entry, void *proc)
1148 struct thread_info *thread = (struct thread_info *) entry;
1149 struct lwp_info *lwp = get_thread_lwp (thread);
1150 struct process_info *process = proc;
1152 if (pid_of (thread) == pid_of (process))
1159 linux_mourn (struct process_info *process)
1161 struct process_info_private *priv;
1163 #ifdef USE_THREAD_DB
1164 thread_db_mourn (process);
1167 find_inferior (&all_threads, delete_lwp_callback, process);
1169 /* Freeing all private data. */
1170 priv = process->private;
1171 free (priv->arch_private);
1173 process->private = NULL;
1175 remove_process (process);
1179 linux_join (int pid)
1184 ret = my_waitpid (pid, &status, 0);
1185 if (WIFEXITED (status) || WIFSIGNALED (status))
1187 } while (ret != -1 || errno != ECHILD);
1190 /* Return nonzero if the given thread is still alive. */
1192 linux_thread_alive (ptid_t ptid)
1194 struct lwp_info *lwp = find_lwp_pid (ptid);
1196 /* We assume we always know if a thread exits. If a whole process
1197 exited but we still haven't been able to report it to GDB, we'll
1198 hold on to the last lwp of the dead process. */
1205 /* Return 1 if this lwp still has an interesting status pending. If
1206 not (e.g., it had stopped for a breakpoint that is gone), return
1210 thread_still_has_status_pending_p (struct thread_info *thread)
1212 struct lwp_info *lp = get_thread_lwp (thread);
1214 if (!lp->status_pending_p)
1217 /* If we got a `vCont;t', but we haven't reported a stop yet, do
1218 report any status pending the LWP may have. */
1219 if (thread->last_resume_kind == resume_stop
1220 && thread->last_status.kind != TARGET_WAITKIND_IGNORE)
1223 if (thread->last_resume_kind != resume_stop
1224 && (lp->stop_reason == LWP_STOPPED_BY_SW_BREAKPOINT
1225 || lp->stop_reason == LWP_STOPPED_BY_HW_BREAKPOINT))
1227 struct thread_info *saved_thread;
1231 gdb_assert (lp->last_status != 0);
1235 saved_thread = current_thread;
1236 current_thread = thread;
1238 if (pc != lp->stop_pc)
1241 debug_printf ("PC of %ld changed\n",
1245 else if (lp->stop_reason == LWP_STOPPED_BY_SW_BREAKPOINT
1246 && !(*the_low_target.breakpoint_at) (pc))
1249 debug_printf ("previous SW breakpoint of %ld gone\n",
1253 else if (lp->stop_reason == LWP_STOPPED_BY_HW_BREAKPOINT
1254 && !hardware_breakpoint_inserted_here (pc))
1257 debug_printf ("previous HW breakpoint of %ld gone\n",
1262 current_thread = saved_thread;
1267 debug_printf ("discarding pending breakpoint status\n");
1268 lp->status_pending_p = 0;
1276 /* Return 1 if this lwp has an interesting status pending. */
1278 status_pending_p_callback (struct inferior_list_entry *entry, void *arg)
1280 struct thread_info *thread = (struct thread_info *) entry;
1281 struct lwp_info *lp = get_thread_lwp (thread);
1282 ptid_t ptid = * (ptid_t *) arg;
1284 /* Check if we're only interested in events from a specific process
1285 or a specific LWP. */
1286 if (!ptid_match (ptid_of (thread), ptid))
1289 if (lp->status_pending_p
1290 && !thread_still_has_status_pending_p (thread))
1292 linux_resume_one_lwp (lp, lp->stepping, GDB_SIGNAL_0, NULL);
1296 return lp->status_pending_p;
1300 same_lwp (struct inferior_list_entry *entry, void *data)
1302 ptid_t ptid = *(ptid_t *) data;
1305 if (ptid_get_lwp (ptid) != 0)
1306 lwp = ptid_get_lwp (ptid);
1308 lwp = ptid_get_pid (ptid);
1310 if (ptid_get_lwp (entry->id) == lwp)
1317 find_lwp_pid (ptid_t ptid)
1319 struct inferior_list_entry *thread
1320 = find_inferior (&all_threads, same_lwp, &ptid);
1325 return get_thread_lwp ((struct thread_info *) thread);
1328 /* Return the number of known LWPs in the tgid given by PID. */
1333 struct inferior_list_entry *inf, *tmp;
1336 ALL_INFERIORS (&all_threads, inf, tmp)
1338 if (ptid_get_pid (inf->id) == pid)
1345 /* Detect zombie thread group leaders, and "exit" them. We can't reap
1346 their exits until all other threads in the group have exited. */
1349 check_zombie_leaders (void)
1351 struct process_info *proc, *tmp;
1353 ALL_PROCESSES (proc, tmp)
1355 pid_t leader_pid = pid_of (proc);
1356 struct lwp_info *leader_lp;
1358 leader_lp = find_lwp_pid (pid_to_ptid (leader_pid));
1361 debug_printf ("leader_pid=%d, leader_lp!=NULL=%d, "
1362 "num_lwps=%d, zombie=%d\n",
1363 leader_pid, leader_lp!= NULL, num_lwps (leader_pid),
1364 linux_proc_pid_is_zombie (leader_pid));
1366 if (leader_lp != NULL
1367 /* Check if there are other threads in the group, as we may
1368 have raced with the inferior simply exiting. */
1369 && !last_thread_of_process_p (leader_pid)
1370 && linux_proc_pid_is_zombie (leader_pid))
1372 /* A leader zombie can mean one of two things:
1374 - It exited, and there's an exit status pending
1375 available, or only the leader exited (not the whole
1376 program). In the latter case, we can't waitpid the
1377 leader's exit status until all other threads are gone.
1379 - There are 3 or more threads in the group, and a thread
1380 other than the leader exec'd. On an exec, the Linux
1381 kernel destroys all other threads (except the execing
1382 one) in the thread group, and resets the execing thread's
1383 tid to the tgid. No exit notification is sent for the
1384 execing thread -- from the ptracer's perspective, it
1385 appears as though the execing thread just vanishes.
1386 Until we reap all other threads except the leader and the
1387 execing thread, the leader will be zombie, and the
1388 execing thread will be in `D (disc sleep)'. As soon as
1389 all other threads are reaped, the execing thread changes
1390 it's tid to the tgid, and the previous (zombie) leader
1391 vanishes, giving place to the "new" leader. We could try
1392 distinguishing the exit and exec cases, by waiting once
1393 more, and seeing if something comes out, but it doesn't
1394 sound useful. The previous leader _does_ go away, and
1395 we'll re-add the new one once we see the exec event
1396 (which is just the same as what would happen if the
1397 previous leader did exit voluntarily before some other
1402 "CZL: Thread group leader %d zombie "
1403 "(it exited, or another thread execd).\n",
1406 delete_lwp (leader_lp);
1411 /* Callback for `find_inferior'. Returns the first LWP that is not
1412 stopped. ARG is a PTID filter. */
1415 not_stopped_callback (struct inferior_list_entry *entry, void *arg)
1417 struct thread_info *thr = (struct thread_info *) entry;
1418 struct lwp_info *lwp;
1419 ptid_t filter = *(ptid_t *) arg;
1421 if (!ptid_match (ptid_of (thr), filter))
1424 lwp = get_thread_lwp (thr);
1431 /* This function should only be called if the LWP got a SIGTRAP.
1433 Handle any tracepoint steps or hits. Return true if a tracepoint
1434 event was handled, 0 otherwise. */
1437 handle_tracepoints (struct lwp_info *lwp)
1439 struct thread_info *tinfo = get_lwp_thread (lwp);
1440 int tpoint_related_event = 0;
1442 gdb_assert (lwp->suspended == 0);
1444 /* If this tracepoint hit causes a tracing stop, we'll immediately
1445 uninsert tracepoints. To do this, we temporarily pause all
1446 threads, unpatch away, and then unpause threads. We need to make
1447 sure the unpausing doesn't resume LWP too. */
1450 /* And we need to be sure that any all-threads-stopping doesn't try
1451 to move threads out of the jump pads, as it could deadlock the
1452 inferior (LWP could be in the jump pad, maybe even holding the
1455 /* Do any necessary step collect actions. */
1456 tpoint_related_event |= tracepoint_finished_step (tinfo, lwp->stop_pc);
1458 tpoint_related_event |= handle_tracepoint_bkpts (tinfo, lwp->stop_pc);
1460 /* See if we just hit a tracepoint and do its main collect
1462 tpoint_related_event |= tracepoint_was_hit (tinfo, lwp->stop_pc);
1466 gdb_assert (lwp->suspended == 0);
1467 gdb_assert (!stabilizing_threads || lwp->collecting_fast_tracepoint);
1469 if (tpoint_related_event)
1472 debug_printf ("got a tracepoint event\n");
1479 /* Convenience wrapper. Returns true if LWP is presently collecting a
1483 linux_fast_tracepoint_collecting (struct lwp_info *lwp,
1484 struct fast_tpoint_collect_status *status)
1486 CORE_ADDR thread_area;
1487 struct thread_info *thread = get_lwp_thread (lwp);
1489 if (the_low_target.get_thread_area == NULL)
1492 /* Get the thread area address. This is used to recognize which
1493 thread is which when tracing with the in-process agent library.
1494 We don't read anything from the address, and treat it as opaque;
1495 it's the address itself that we assume is unique per-thread. */
1496 if ((*the_low_target.get_thread_area) (lwpid_of (thread), &thread_area) == -1)
1499 return fast_tracepoint_collecting (thread_area, lwp->stop_pc, status);
1502 /* The reason we resume in the caller, is because we want to be able
1503 to pass lwp->status_pending as WSTAT, and we need to clear
1504 status_pending_p before resuming, otherwise, linux_resume_one_lwp
1505 refuses to resume. */
1508 maybe_move_out_of_jump_pad (struct lwp_info *lwp, int *wstat)
1510 struct thread_info *saved_thread;
1512 saved_thread = current_thread;
1513 current_thread = get_lwp_thread (lwp);
1516 || (WIFSTOPPED (*wstat) && WSTOPSIG (*wstat) != SIGTRAP))
1517 && supports_fast_tracepoints ()
1518 && agent_loaded_p ())
1520 struct fast_tpoint_collect_status status;
1524 debug_printf ("Checking whether LWP %ld needs to move out of the "
1526 lwpid_of (current_thread));
1528 r = linux_fast_tracepoint_collecting (lwp, &status);
1531 || (WSTOPSIG (*wstat) != SIGILL
1532 && WSTOPSIG (*wstat) != SIGFPE
1533 && WSTOPSIG (*wstat) != SIGSEGV
1534 && WSTOPSIG (*wstat) != SIGBUS))
1536 lwp->collecting_fast_tracepoint = r;
1540 if (r == 1 && lwp->exit_jump_pad_bkpt == NULL)
1542 /* Haven't executed the original instruction yet.
1543 Set breakpoint there, and wait till it's hit,
1544 then single-step until exiting the jump pad. */
1545 lwp->exit_jump_pad_bkpt
1546 = set_breakpoint_at (status.adjusted_insn_addr, NULL);
1550 debug_printf ("Checking whether LWP %ld needs to move out of "
1551 "the jump pad...it does\n",
1552 lwpid_of (current_thread));
1553 current_thread = saved_thread;
1560 /* If we get a synchronous signal while collecting, *and*
1561 while executing the (relocated) original instruction,
1562 reset the PC to point at the tpoint address, before
1563 reporting to GDB. Otherwise, it's an IPA lib bug: just
1564 report the signal to GDB, and pray for the best. */
1566 lwp->collecting_fast_tracepoint = 0;
1569 && (status.adjusted_insn_addr <= lwp->stop_pc
1570 && lwp->stop_pc < status.adjusted_insn_addr_end))
1573 struct regcache *regcache;
1575 /* The si_addr on a few signals references the address
1576 of the faulting instruction. Adjust that as
1578 if ((WSTOPSIG (*wstat) == SIGILL
1579 || WSTOPSIG (*wstat) == SIGFPE
1580 || WSTOPSIG (*wstat) == SIGBUS
1581 || WSTOPSIG (*wstat) == SIGSEGV)
1582 && ptrace (PTRACE_GETSIGINFO, lwpid_of (current_thread),
1583 (PTRACE_TYPE_ARG3) 0, &info) == 0
1584 /* Final check just to make sure we don't clobber
1585 the siginfo of non-kernel-sent signals. */
1586 && (uintptr_t) info.si_addr == lwp->stop_pc)
1588 info.si_addr = (void *) (uintptr_t) status.tpoint_addr;
1589 ptrace (PTRACE_SETSIGINFO, lwpid_of (current_thread),
1590 (PTRACE_TYPE_ARG3) 0, &info);
1593 regcache = get_thread_regcache (current_thread, 1);
1594 (*the_low_target.set_pc) (regcache, status.tpoint_addr);
1595 lwp->stop_pc = status.tpoint_addr;
1597 /* Cancel any fast tracepoint lock this thread was
1599 force_unlock_trace_buffer ();
1602 if (lwp->exit_jump_pad_bkpt != NULL)
1605 debug_printf ("Cancelling fast exit-jump-pad: removing bkpt. "
1606 "stopping all threads momentarily.\n");
1608 stop_all_lwps (1, lwp);
1610 delete_breakpoint (lwp->exit_jump_pad_bkpt);
1611 lwp->exit_jump_pad_bkpt = NULL;
1613 unstop_all_lwps (1, lwp);
1615 gdb_assert (lwp->suspended >= 0);
1621 debug_printf ("Checking whether LWP %ld needs to move out of the "
1623 lwpid_of (current_thread));
1625 current_thread = saved_thread;
1629 /* Enqueue one signal in the "signals to report later when out of the
1633 enqueue_one_deferred_signal (struct lwp_info *lwp, int *wstat)
1635 struct pending_signals *p_sig;
1636 struct thread_info *thread = get_lwp_thread (lwp);
1639 debug_printf ("Deferring signal %d for LWP %ld.\n",
1640 WSTOPSIG (*wstat), lwpid_of (thread));
1644 struct pending_signals *sig;
1646 for (sig = lwp->pending_signals_to_report;
1649 debug_printf (" Already queued %d\n",
1652 debug_printf (" (no more currently queued signals)\n");
1655 /* Don't enqueue non-RT signals if they are already in the deferred
1656 queue. (SIGSTOP being the easiest signal to see ending up here
1658 if (WSTOPSIG (*wstat) < __SIGRTMIN)
1660 struct pending_signals *sig;
1662 for (sig = lwp->pending_signals_to_report;
1666 if (sig->signal == WSTOPSIG (*wstat))
1669 debug_printf ("Not requeuing already queued non-RT signal %d"
1678 p_sig = xmalloc (sizeof (*p_sig));
1679 p_sig->prev = lwp->pending_signals_to_report;
1680 p_sig->signal = WSTOPSIG (*wstat);
1681 memset (&p_sig->info, 0, sizeof (siginfo_t));
1682 ptrace (PTRACE_GETSIGINFO, lwpid_of (thread), (PTRACE_TYPE_ARG3) 0,
1685 lwp->pending_signals_to_report = p_sig;
1688 /* Dequeue one signal from the "signals to report later when out of
1689 the jump pad" list. */
1692 dequeue_one_deferred_signal (struct lwp_info *lwp, int *wstat)
1694 struct thread_info *thread = get_lwp_thread (lwp);
1696 if (lwp->pending_signals_to_report != NULL)
1698 struct pending_signals **p_sig;
1700 p_sig = &lwp->pending_signals_to_report;
1701 while ((*p_sig)->prev != NULL)
1702 p_sig = &(*p_sig)->prev;
1704 *wstat = W_STOPCODE ((*p_sig)->signal);
1705 if ((*p_sig)->info.si_signo != 0)
1706 ptrace (PTRACE_SETSIGINFO, lwpid_of (thread), (PTRACE_TYPE_ARG3) 0,
1712 debug_printf ("Reporting deferred signal %d for LWP %ld.\n",
1713 WSTOPSIG (*wstat), lwpid_of (thread));
1717 struct pending_signals *sig;
1719 for (sig = lwp->pending_signals_to_report;
1722 debug_printf (" Still queued %d\n",
1725 debug_printf (" (no more queued signals)\n");
1734 /* Fetch the possibly triggered data watchpoint info and store it in
1737 On some archs, like x86, that use debug registers to set
1738 watchpoints, it's possible that the way to know which watched
1739 address trapped, is to check the register that is used to select
1740 which address to watch. Problem is, between setting the watchpoint
1741 and reading back which data address trapped, the user may change
1742 the set of watchpoints, and, as a consequence, GDB changes the
1743 debug registers in the inferior. To avoid reading back a stale
1744 stopped-data-address when that happens, we cache in LP the fact
1745 that a watchpoint trapped, and the corresponding data address, as
1746 soon as we see CHILD stop with a SIGTRAP. If GDB changes the debug
1747 registers meanwhile, we have the cached data we can rely on. */
1750 check_stopped_by_watchpoint (struct lwp_info *child)
1752 if (the_low_target.stopped_by_watchpoint != NULL)
1754 struct thread_info *saved_thread;
1756 saved_thread = current_thread;
1757 current_thread = get_lwp_thread (child);
1759 if (the_low_target.stopped_by_watchpoint ())
1761 child->stop_reason = LWP_STOPPED_BY_WATCHPOINT;
1763 if (the_low_target.stopped_data_address != NULL)
1764 child->stopped_data_address
1765 = the_low_target.stopped_data_address ();
1767 child->stopped_data_address = 0;
1770 current_thread = saved_thread;
1773 return child->stop_reason == LWP_STOPPED_BY_WATCHPOINT;
1776 /* Do low-level handling of the event, and check if we should go on
1777 and pass it to caller code. Return the affected lwp if we are, or
1780 static struct lwp_info *
1781 linux_low_filter_event (int lwpid, int wstat)
1783 struct lwp_info *child;
1784 struct thread_info *thread;
1785 int have_stop_pc = 0;
1787 child = find_lwp_pid (pid_to_ptid (lwpid));
1789 /* If we didn't find a process, one of two things presumably happened:
1790 - A process we started and then detached from has exited. Ignore it.
1791 - A process we are controlling has forked and the new child's stop
1792 was reported to us by the kernel. Save its PID. */
1793 if (child == NULL && WIFSTOPPED (wstat))
1795 add_to_pid_list (&stopped_pids, lwpid, wstat);
1798 else if (child == NULL)
1801 thread = get_lwp_thread (child);
1805 child->last_status = wstat;
1807 /* Check if the thread has exited. */
1808 if ((WIFEXITED (wstat) || WIFSIGNALED (wstat)))
1811 debug_printf ("LLFE: %d exited.\n", lwpid);
1812 if (num_lwps (pid_of (thread)) > 1)
1815 /* If there is at least one more LWP, then the exit signal was
1816 not the end of the debugged application and should be
1823 /* This was the last lwp in the process. Since events are
1824 serialized to GDB core, and we can't report this one
1825 right now, but GDB core and the other target layers will
1826 want to be notified about the exit code/signal, leave the
1827 status pending for the next time we're able to report
1829 mark_lwp_dead (child, wstat);
1834 gdb_assert (WIFSTOPPED (wstat));
1836 if (WIFSTOPPED (wstat))
1838 struct process_info *proc;
1840 /* Architecture-specific setup after inferior is running. This
1841 needs to happen after we have attached to the inferior and it
1842 is stopped for the first time, but before we access any
1843 inferior registers. */
1844 proc = find_process_pid (pid_of (thread));
1845 if (proc->private->new_inferior)
1847 struct thread_info *saved_thread;
1849 saved_thread = current_thread;
1850 current_thread = thread;
1852 the_low_target.arch_setup ();
1854 current_thread = saved_thread;
1856 proc->private->new_inferior = 0;
1860 if (WIFSTOPPED (wstat) && child->must_set_ptrace_flags)
1862 struct process_info *proc = find_process_pid (pid_of (thread));
1864 linux_enable_event_reporting (lwpid, proc->attached);
1865 child->must_set_ptrace_flags = 0;
1868 /* Be careful to not overwrite stop_pc until
1869 check_stopped_by_breakpoint is called. */
1870 if (WIFSTOPPED (wstat) && WSTOPSIG (wstat) == SIGTRAP
1871 && linux_is_extended_waitstatus (wstat))
1873 child->stop_pc = get_pc (child);
1874 handle_extended_wait (child, wstat);
1878 if (WIFSTOPPED (wstat) && WSTOPSIG (wstat) == SIGTRAP
1879 && check_stopped_by_watchpoint (child))
1881 else if (WIFSTOPPED (wstat) && linux_wstatus_maybe_breakpoint (wstat))
1883 if (check_stopped_by_breakpoint (child))
1888 child->stop_pc = get_pc (child);
1890 if (WIFSTOPPED (wstat) && WSTOPSIG (wstat) == SIGSTOP
1891 && child->stop_expected)
1894 debug_printf ("Expected stop.\n");
1895 child->stop_expected = 0;
1897 if (thread->last_resume_kind == resume_stop)
1899 /* We want to report the stop to the core. Treat the
1900 SIGSTOP as a normal event. */
1902 else if (stopping_threads != NOT_STOPPING_THREADS)
1904 /* Stopping threads. We don't want this SIGSTOP to end up
1910 /* Filter out the event. */
1911 linux_resume_one_lwp (child, child->stepping, 0, NULL);
1916 child->status_pending_p = 1;
1917 child->status_pending = wstat;
1921 /* Resume LWPs that are currently stopped without any pending status
1922 to report, but are resumed from the core's perspective. */
1925 resume_stopped_resumed_lwps (struct inferior_list_entry *entry)
1927 struct thread_info *thread = (struct thread_info *) entry;
1928 struct lwp_info *lp = get_thread_lwp (thread);
1931 && !lp->status_pending_p
1932 && thread->last_resume_kind != resume_stop
1933 && thread->last_status.kind == TARGET_WAITKIND_IGNORE)
1935 int step = thread->last_resume_kind == resume_step;
1938 debug_printf ("RSRL: resuming stopped-resumed LWP %s at %s: step=%d\n",
1939 target_pid_to_str (ptid_of (thread)),
1940 paddress (lp->stop_pc),
1943 linux_resume_one_lwp (lp, step, GDB_SIGNAL_0, NULL);
1947 /* Wait for an event from child(ren) WAIT_PTID, and return any that
1948 match FILTER_PTID (leaving others pending). The PTIDs can be:
1949 minus_one_ptid, to specify any child; a pid PTID, specifying all
1950 lwps of a thread group; or a PTID representing a single lwp. Store
1951 the stop status through the status pointer WSTAT. OPTIONS is
1952 passed to the waitpid call. Return 0 if no event was found and
1953 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
1954 was found. Return the PID of the stopped child otherwise. */
1957 linux_wait_for_event_filtered (ptid_t wait_ptid, ptid_t filter_ptid,
1958 int *wstatp, int options)
1960 struct thread_info *event_thread;
1961 struct lwp_info *event_child, *requested_child;
1962 sigset_t block_mask, prev_mask;
1965 /* N.B. event_thread points to the thread_info struct that contains
1966 event_child. Keep them in sync. */
1967 event_thread = NULL;
1969 requested_child = NULL;
1971 /* Check for a lwp with a pending status. */
1973 if (ptid_equal (filter_ptid, minus_one_ptid) || ptid_is_pid (filter_ptid))
1975 event_thread = (struct thread_info *)
1976 find_inferior (&all_threads, status_pending_p_callback, &filter_ptid);
1977 if (event_thread != NULL)
1978 event_child = get_thread_lwp (event_thread);
1979 if (debug_threads && event_thread)
1980 debug_printf ("Got a pending child %ld\n", lwpid_of (event_thread));
1982 else if (!ptid_equal (filter_ptid, null_ptid))
1984 requested_child = find_lwp_pid (filter_ptid);
1986 if (stopping_threads == NOT_STOPPING_THREADS
1987 && requested_child->status_pending_p
1988 && requested_child->collecting_fast_tracepoint)
1990 enqueue_one_deferred_signal (requested_child,
1991 &requested_child->status_pending);
1992 requested_child->status_pending_p = 0;
1993 requested_child->status_pending = 0;
1994 linux_resume_one_lwp (requested_child, 0, 0, NULL);
1997 if (requested_child->suspended
1998 && requested_child->status_pending_p)
2000 internal_error (__FILE__, __LINE__,
2001 "requesting an event out of a"
2002 " suspended child?");
2005 if (requested_child->status_pending_p)
2007 event_child = requested_child;
2008 event_thread = get_lwp_thread (event_child);
2012 if (event_child != NULL)
2015 debug_printf ("Got an event from pending child %ld (%04x)\n",
2016 lwpid_of (event_thread), event_child->status_pending);
2017 *wstatp = event_child->status_pending;
2018 event_child->status_pending_p = 0;
2019 event_child->status_pending = 0;
2020 current_thread = event_thread;
2021 return lwpid_of (event_thread);
2024 /* But if we don't find a pending event, we'll have to wait.
2026 We only enter this loop if no process has a pending wait status.
2027 Thus any action taken in response to a wait status inside this
2028 loop is responding as soon as we detect the status, not after any
2031 /* Make sure SIGCHLD is blocked until the sigsuspend below. Block
2032 all signals while here. */
2033 sigfillset (&block_mask);
2034 sigprocmask (SIG_BLOCK, &block_mask, &prev_mask);
2036 /* Always pull all events out of the kernel. We'll randomly select
2037 an event LWP out of all that have events, to prevent
2039 while (event_child == NULL)
2043 /* Always use -1 and WNOHANG, due to couple of a kernel/ptrace
2046 - If the thread group leader exits while other threads in the
2047 thread group still exist, waitpid(TGID, ...) hangs. That
2048 waitpid won't return an exit status until the other threads
2049 in the group are reaped.
2051 - When a non-leader thread execs, that thread just vanishes
2052 without reporting an exit (so we'd hang if we waited for it
2053 explicitly in that case). The exec event is reported to
2054 the TGID pid (although we don't currently enable exec
2057 ret = my_waitpid (-1, wstatp, options | WNOHANG);
2060 debug_printf ("LWFE: waitpid(-1, ...) returned %d, %s\n",
2061 ret, errno ? strerror (errno) : "ERRNO-OK");
2067 debug_printf ("LLW: waitpid %ld received %s\n",
2068 (long) ret, status_to_str (*wstatp));
2071 /* Filter all events. IOW, leave all events pending. We'll
2072 randomly select an event LWP out of all that have events
2074 linux_low_filter_event (ret, *wstatp);
2075 /* Retry until nothing comes out of waitpid. A single
2076 SIGCHLD can indicate more than one child stopped. */
2080 /* Now that we've pulled all events out of the kernel, resume
2081 LWPs that don't have an interesting event to report. */
2082 if (stopping_threads == NOT_STOPPING_THREADS)
2083 for_each_inferior (&all_threads, resume_stopped_resumed_lwps);
2085 /* ... and find an LWP with a status to report to the core, if
2087 event_thread = (struct thread_info *)
2088 find_inferior (&all_threads, status_pending_p_callback, &filter_ptid);
2089 if (event_thread != NULL)
2091 event_child = get_thread_lwp (event_thread);
2092 *wstatp = event_child->status_pending;
2093 event_child->status_pending_p = 0;
2094 event_child->status_pending = 0;
2098 /* Check for zombie thread group leaders. Those can't be reaped
2099 until all other threads in the thread group are. */
2100 check_zombie_leaders ();
2102 /* If there are no resumed children left in the set of LWPs we
2103 want to wait for, bail. We can't just block in
2104 waitpid/sigsuspend, because lwps might have been left stopped
2105 in trace-stop state, and we'd be stuck forever waiting for
2106 their status to change (which would only happen if we resumed
2107 them). Even if WNOHANG is set, this return code is preferred
2108 over 0 (below), as it is more detailed. */
2109 if ((find_inferior (&all_threads,
2110 not_stopped_callback,
2111 &wait_ptid) == NULL))
2114 debug_printf ("LLW: exit (no unwaited-for LWP)\n");
2115 sigprocmask (SIG_SETMASK, &prev_mask, NULL);
2119 /* No interesting event to report to the caller. */
2120 if ((options & WNOHANG))
2123 debug_printf ("WNOHANG set, no event found\n");
2125 sigprocmask (SIG_SETMASK, &prev_mask, NULL);
2129 /* Block until we get an event reported with SIGCHLD. */
2131 debug_printf ("sigsuspend'ing\n");
2133 sigsuspend (&prev_mask);
2134 sigprocmask (SIG_SETMASK, &prev_mask, NULL);
2138 sigprocmask (SIG_SETMASK, &prev_mask, NULL);
2140 current_thread = event_thread;
2142 /* Check for thread exit. */
2143 if (! WIFSTOPPED (*wstatp))
2145 gdb_assert (last_thread_of_process_p (pid_of (event_thread)));
2148 debug_printf ("LWP %d is the last lwp of process. "
2149 "Process %ld exiting.\n",
2150 pid_of (event_thread), lwpid_of (event_thread));
2151 return lwpid_of (event_thread);
2154 return lwpid_of (event_thread);
2157 /* Wait for an event from child(ren) PTID. PTIDs can be:
2158 minus_one_ptid, to specify any child; a pid PTID, specifying all
2159 lwps of a thread group; or a PTID representing a single lwp. Store
2160 the stop status through the status pointer WSTAT. OPTIONS is
2161 passed to the waitpid call. Return 0 if no event was found and
2162 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
2163 was found. Return the PID of the stopped child otherwise. */
2166 linux_wait_for_event (ptid_t ptid, int *wstatp, int options)
2168 return linux_wait_for_event_filtered (ptid, ptid, wstatp, options);
2171 /* Count the LWP's that have had events. */
2174 count_events_callback (struct inferior_list_entry *entry, void *data)
2176 struct thread_info *thread = (struct thread_info *) entry;
2179 gdb_assert (count != NULL);
2181 /* Count only resumed LWPs that have an event pending. */
2182 if (thread->last_status.kind == TARGET_WAITKIND_IGNORE
2183 && thread->last_resume_kind != resume_stop
2184 && thread->status_pending_p)
2190 /* Select the LWP (if any) that is currently being single-stepped. */
2193 select_singlestep_lwp_callback (struct inferior_list_entry *entry, void *data)
2195 struct thread_info *thread = (struct thread_info *) entry;
2196 struct lwp_info *lp = get_thread_lwp (thread);
2198 if (thread->last_status.kind == TARGET_WAITKIND_IGNORE
2199 && thread->last_resume_kind == resume_step
2200 && lp->status_pending_p)
2206 /* Select the Nth LWP that has had a SIGTRAP event that should be
2210 select_event_lwp_callback (struct inferior_list_entry *entry, void *data)
2212 struct thread_info *thread = (struct thread_info *) entry;
2213 int *selector = data;
2215 gdb_assert (selector != NULL);
2217 /* Select only resumed LWPs that have an event pending. */
2218 if (thread->last_resume_kind != resume_stop
2219 && thread->last_status.kind == TARGET_WAITKIND_IGNORE
2220 && thread->status_pending_p)
2221 if ((*selector)-- == 0)
2227 /* Select one LWP out of those that have events pending. */
2230 select_event_lwp (struct lwp_info **orig_lp)
2233 int random_selector;
2234 struct thread_info *event_thread = NULL;
2236 /* In all-stop, give preference to the LWP that is being
2237 single-stepped. There will be at most one, and it's the LWP that
2238 the core is most interested in. If we didn't do this, then we'd
2239 have to handle pending step SIGTRAPs somehow in case the core
2240 later continues the previously-stepped thread, otherwise we'd
2241 report the pending SIGTRAP, and the core, not having stepped the
2242 thread, wouldn't understand what the trap was for, and therefore
2243 would report it to the user as a random signal. */
2247 = (struct thread_info *) find_inferior (&all_threads,
2248 select_singlestep_lwp_callback,
2250 if (event_thread != NULL)
2253 debug_printf ("SEL: Select single-step %s\n",
2254 target_pid_to_str (ptid_of (event_thread)));
2257 if (event_thread == NULL)
2259 /* No single-stepping LWP. Select one at random, out of those
2260 which have had SIGTRAP events. */
2262 /* First see how many SIGTRAP events we have. */
2263 find_inferior (&all_threads, count_events_callback, &num_events);
2265 /* Now randomly pick a LWP out of those that have had a SIGTRAP. */
2266 random_selector = (int)
2267 ((num_events * (double) rand ()) / (RAND_MAX + 1.0));
2269 if (debug_threads && num_events > 1)
2270 debug_printf ("SEL: Found %d SIGTRAP events, selecting #%d\n",
2271 num_events, random_selector);
2274 = (struct thread_info *) find_inferior (&all_threads,
2275 select_event_lwp_callback,
2279 if (event_thread != NULL)
2281 struct lwp_info *event_lp = get_thread_lwp (event_thread);
2283 /* Switch the event LWP. */
2284 *orig_lp = event_lp;
2288 /* Decrement the suspend count of an LWP. */
2291 unsuspend_one_lwp (struct inferior_list_entry *entry, void *except)
2293 struct thread_info *thread = (struct thread_info *) entry;
2294 struct lwp_info *lwp = get_thread_lwp (thread);
2296 /* Ignore EXCEPT. */
2302 gdb_assert (lwp->suspended >= 0);
2306 /* Decrement the suspend count of all LWPs, except EXCEPT, if non
2310 unsuspend_all_lwps (struct lwp_info *except)
2312 find_inferior (&all_threads, unsuspend_one_lwp, except);
2315 static void move_out_of_jump_pad_callback (struct inferior_list_entry *entry);
2316 static int stuck_in_jump_pad_callback (struct inferior_list_entry *entry,
2318 static int lwp_running (struct inferior_list_entry *entry, void *data);
2319 static ptid_t linux_wait_1 (ptid_t ptid,
2320 struct target_waitstatus *ourstatus,
2321 int target_options);
2323 /* Stabilize threads (move out of jump pads).
2325 If a thread is midway collecting a fast tracepoint, we need to
2326 finish the collection and move it out of the jump pad before
2327 reporting the signal.
2329 This avoids recursion while collecting (when a signal arrives
2330 midway, and the signal handler itself collects), which would trash
2331 the trace buffer. In case the user set a breakpoint in a signal
2332 handler, this avoids the backtrace showing the jump pad, etc..
2333 Most importantly, there are certain things we can't do safely if
2334 threads are stopped in a jump pad (or in its callee's). For
2337 - starting a new trace run. A thread still collecting the
2338 previous run, could trash the trace buffer when resumed. The trace
2339 buffer control structures would have been reset but the thread had
2340 no way to tell. The thread could even midway memcpy'ing to the
2341 buffer, which would mean that when resumed, it would clobber the
2342 trace buffer that had been set for a new run.
2344 - we can't rewrite/reuse the jump pads for new tracepoints
2345 safely. Say you do tstart while a thread is stopped midway while
2346 collecting. When the thread is later resumed, it finishes the
2347 collection, and returns to the jump pad, to execute the original
2348 instruction that was under the tracepoint jump at the time the
2349 older run had been started. If the jump pad had been rewritten
2350 since for something else in the new run, the thread would now
2351 execute the wrong / random instructions. */
2354 linux_stabilize_threads (void)
2356 struct thread_info *saved_thread;
2357 struct thread_info *thread_stuck;
2360 = (struct thread_info *) find_inferior (&all_threads,
2361 stuck_in_jump_pad_callback,
2363 if (thread_stuck != NULL)
2366 debug_printf ("can't stabilize, LWP %ld is stuck in jump pad\n",
2367 lwpid_of (thread_stuck));
2371 saved_thread = current_thread;
2373 stabilizing_threads = 1;
2376 for_each_inferior (&all_threads, move_out_of_jump_pad_callback);
2378 /* Loop until all are stopped out of the jump pads. */
2379 while (find_inferior (&all_threads, lwp_running, NULL) != NULL)
2381 struct target_waitstatus ourstatus;
2382 struct lwp_info *lwp;
2385 /* Note that we go through the full wait even loop. While
2386 moving threads out of jump pad, we need to be able to step
2387 over internal breakpoints and such. */
2388 linux_wait_1 (minus_one_ptid, &ourstatus, 0);
2390 if (ourstatus.kind == TARGET_WAITKIND_STOPPED)
2392 lwp = get_thread_lwp (current_thread);
2397 if (ourstatus.value.sig != GDB_SIGNAL_0
2398 || current_thread->last_resume_kind == resume_stop)
2400 wstat = W_STOPCODE (gdb_signal_to_host (ourstatus.value.sig));
2401 enqueue_one_deferred_signal (lwp, &wstat);
2406 find_inferior (&all_threads, unsuspend_one_lwp, NULL);
2408 stabilizing_threads = 0;
2410 current_thread = saved_thread;
2415 = (struct thread_info *) find_inferior (&all_threads,
2416 stuck_in_jump_pad_callback,
2418 if (thread_stuck != NULL)
2419 debug_printf ("couldn't stabilize, LWP %ld got stuck in jump pad\n",
2420 lwpid_of (thread_stuck));
2424 static void async_file_mark (void);
2426 /* Convenience function that is called when the kernel reports an
2427 event that is not passed out to GDB. */
2430 ignore_event (struct target_waitstatus *ourstatus)
2432 /* If we got an event, there may still be others, as a single
2433 SIGCHLD can indicate more than one child stopped. This forces
2434 another target_wait call. */
2437 ourstatus->kind = TARGET_WAITKIND_IGNORE;
2441 /* Wait for process, returns status. */
2444 linux_wait_1 (ptid_t ptid,
2445 struct target_waitstatus *ourstatus, int target_options)
2448 struct lwp_info *event_child;
2451 int step_over_finished;
2452 int bp_explains_trap;
2453 int maybe_internal_trap;
2461 debug_printf ("linux_wait_1: [%s]\n", target_pid_to_str (ptid));
2464 /* Translate generic target options into linux options. */
2466 if (target_options & TARGET_WNOHANG)
2469 bp_explains_trap = 0;
2472 ourstatus->kind = TARGET_WAITKIND_IGNORE;
2474 if (ptid_equal (step_over_bkpt, null_ptid))
2475 pid = linux_wait_for_event (ptid, &w, options);
2479 debug_printf ("step_over_bkpt set [%s], doing a blocking wait\n",
2480 target_pid_to_str (step_over_bkpt));
2481 pid = linux_wait_for_event (step_over_bkpt, &w, options & ~WNOHANG);
2486 gdb_assert (target_options & TARGET_WNOHANG);
2490 debug_printf ("linux_wait_1 ret = null_ptid, "
2491 "TARGET_WAITKIND_IGNORE\n");
2495 ourstatus->kind = TARGET_WAITKIND_IGNORE;
2502 debug_printf ("linux_wait_1 ret = null_ptid, "
2503 "TARGET_WAITKIND_NO_RESUMED\n");
2507 ourstatus->kind = TARGET_WAITKIND_NO_RESUMED;
2511 event_child = get_thread_lwp (current_thread);
2513 /* linux_wait_for_event only returns an exit status for the last
2514 child of a process. Report it. */
2515 if (WIFEXITED (w) || WIFSIGNALED (w))
2519 ourstatus->kind = TARGET_WAITKIND_EXITED;
2520 ourstatus->value.integer = WEXITSTATUS (w);
2524 debug_printf ("linux_wait_1 ret = %s, exited with "
2526 target_pid_to_str (ptid_of (current_thread)),
2533 ourstatus->kind = TARGET_WAITKIND_SIGNALLED;
2534 ourstatus->value.sig = gdb_signal_from_host (WTERMSIG (w));
2538 debug_printf ("linux_wait_1 ret = %s, terminated with "
2540 target_pid_to_str (ptid_of (current_thread)),
2546 return ptid_of (current_thread);
2549 /* If step-over executes a breakpoint instruction, it means a
2550 gdb/gdbserver breakpoint had been planted on top of a permanent
2551 breakpoint. The PC has been adjusted by
2552 check_stopped_by_breakpoint to point at the breakpoint address.
2553 Advance the PC manually past the breakpoint, otherwise the
2554 program would keep trapping the permanent breakpoint forever. */
2555 if (!ptid_equal (step_over_bkpt, null_ptid)
2556 && event_child->stop_reason == LWP_STOPPED_BY_SW_BREAKPOINT)
2558 unsigned int increment_pc;
2560 if (the_low_target.breakpoint_len > the_low_target.decr_pc_after_break)
2561 increment_pc = the_low_target.breakpoint_len;
2563 increment_pc = the_low_target.decr_pc_after_break;
2567 debug_printf ("step-over for %s executed software breakpoint\n",
2568 target_pid_to_str (ptid_of (current_thread)));
2571 if (increment_pc != 0)
2573 struct regcache *regcache
2574 = get_thread_regcache (current_thread, 1);
2576 event_child->stop_pc += increment_pc;
2577 (*the_low_target.set_pc) (regcache, event_child->stop_pc);
2579 if (!(*the_low_target.breakpoint_at) (event_child->stop_pc))
2580 event_child->stop_reason = LWP_STOPPED_BY_NO_REASON;
2584 /* If this event was not handled before, and is not a SIGTRAP, we
2585 report it. SIGILL and SIGSEGV are also treated as traps in case
2586 a breakpoint is inserted at the current PC. If this target does
2587 not support internal breakpoints at all, we also report the
2588 SIGTRAP without further processing; it's of no concern to us. */
2590 = (supports_breakpoints ()
2591 && (WSTOPSIG (w) == SIGTRAP
2592 || ((WSTOPSIG (w) == SIGILL
2593 || WSTOPSIG (w) == SIGSEGV)
2594 && (*the_low_target.breakpoint_at) (event_child->stop_pc))));
2596 if (maybe_internal_trap)
2598 /* Handle anything that requires bookkeeping before deciding to
2599 report the event or continue waiting. */
2601 /* First check if we can explain the SIGTRAP with an internal
2602 breakpoint, or if we should possibly report the event to GDB.
2603 Do this before anything that may remove or insert a
2605 bp_explains_trap = breakpoint_inserted_here (event_child->stop_pc);
2607 /* We have a SIGTRAP, possibly a step-over dance has just
2608 finished. If so, tweak the state machine accordingly,
2609 reinsert breakpoints and delete any reinsert (software
2610 single-step) breakpoints. */
2611 step_over_finished = finish_step_over (event_child);
2613 /* Now invoke the callbacks of any internal breakpoints there. */
2614 check_breakpoints (event_child->stop_pc);
2616 /* Handle tracepoint data collecting. This may overflow the
2617 trace buffer, and cause a tracing stop, removing
2619 trace_event = handle_tracepoints (event_child);
2621 if (bp_explains_trap)
2623 /* If we stepped or ran into an internal breakpoint, we've
2624 already handled it. So next time we resume (from this
2625 PC), we should step over it. */
2627 debug_printf ("Hit a gdbserver breakpoint.\n");
2629 if (breakpoint_here (event_child->stop_pc))
2630 event_child->need_step_over = 1;
2635 /* We have some other signal, possibly a step-over dance was in
2636 progress, and it should be cancelled too. */
2637 step_over_finished = finish_step_over (event_child);
2640 /* We have all the data we need. Either report the event to GDB, or
2641 resume threads and keep waiting for more. */
2643 /* If we're collecting a fast tracepoint, finish the collection and
2644 move out of the jump pad before delivering a signal. See
2645 linux_stabilize_threads. */
2648 && WSTOPSIG (w) != SIGTRAP
2649 && supports_fast_tracepoints ()
2650 && agent_loaded_p ())
2653 debug_printf ("Got signal %d for LWP %ld. Check if we need "
2654 "to defer or adjust it.\n",
2655 WSTOPSIG (w), lwpid_of (current_thread));
2657 /* Allow debugging the jump pad itself. */
2658 if (current_thread->last_resume_kind != resume_step
2659 && maybe_move_out_of_jump_pad (event_child, &w))
2661 enqueue_one_deferred_signal (event_child, &w);
2664 debug_printf ("Signal %d for LWP %ld deferred (in jump pad)\n",
2665 WSTOPSIG (w), lwpid_of (current_thread));
2667 linux_resume_one_lwp (event_child, 0, 0, NULL);
2669 return ignore_event (ourstatus);
2673 if (event_child->collecting_fast_tracepoint)
2676 debug_printf ("LWP %ld was trying to move out of the jump pad (%d). "
2677 "Check if we're already there.\n",
2678 lwpid_of (current_thread),
2679 event_child->collecting_fast_tracepoint);
2683 event_child->collecting_fast_tracepoint
2684 = linux_fast_tracepoint_collecting (event_child, NULL);
2686 if (event_child->collecting_fast_tracepoint != 1)
2688 /* No longer need this breakpoint. */
2689 if (event_child->exit_jump_pad_bkpt != NULL)
2692 debug_printf ("No longer need exit-jump-pad bkpt; removing it."
2693 "stopping all threads momentarily.\n");
2695 /* Other running threads could hit this breakpoint.
2696 We don't handle moribund locations like GDB does,
2697 instead we always pause all threads when removing
2698 breakpoints, so that any step-over or
2699 decr_pc_after_break adjustment is always taken
2700 care of while the breakpoint is still
2702 stop_all_lwps (1, event_child);
2704 delete_breakpoint (event_child->exit_jump_pad_bkpt);
2705 event_child->exit_jump_pad_bkpt = NULL;
2707 unstop_all_lwps (1, event_child);
2709 gdb_assert (event_child->suspended >= 0);
2713 if (event_child->collecting_fast_tracepoint == 0)
2716 debug_printf ("fast tracepoint finished "
2717 "collecting successfully.\n");
2719 /* We may have a deferred signal to report. */
2720 if (dequeue_one_deferred_signal (event_child, &w))
2723 debug_printf ("dequeued one signal.\n");
2728 debug_printf ("no deferred signals.\n");
2730 if (stabilizing_threads)
2732 ourstatus->kind = TARGET_WAITKIND_STOPPED;
2733 ourstatus->value.sig = GDB_SIGNAL_0;
2737 debug_printf ("linux_wait_1 ret = %s, stopped "
2738 "while stabilizing threads\n",
2739 target_pid_to_str (ptid_of (current_thread)));
2743 return ptid_of (current_thread);
2749 /* Check whether GDB would be interested in this event. */
2751 /* If GDB is not interested in this signal, don't stop other
2752 threads, and don't report it to GDB. Just resume the inferior
2753 right away. We do this for threading-related signals as well as
2754 any that GDB specifically requested we ignore. But never ignore
2755 SIGSTOP if we sent it ourselves, and do not ignore signals when
2756 stepping - they may require special handling to skip the signal
2757 handler. Also never ignore signals that could be caused by a
2759 /* FIXME drow/2002-06-09: Get signal numbers from the inferior's
2762 && current_thread->last_resume_kind != resume_step
2764 #if defined (USE_THREAD_DB) && !defined (__ANDROID__)
2765 (current_process ()->private->thread_db != NULL
2766 && (WSTOPSIG (w) == __SIGRTMIN
2767 || WSTOPSIG (w) == __SIGRTMIN + 1))
2770 (pass_signals[gdb_signal_from_host (WSTOPSIG (w))]
2771 && !(WSTOPSIG (w) == SIGSTOP
2772 && current_thread->last_resume_kind == resume_stop)
2773 && !linux_wstatus_maybe_breakpoint (w))))
2775 siginfo_t info, *info_p;
2778 debug_printf ("Ignored signal %d for LWP %ld.\n",
2779 WSTOPSIG (w), lwpid_of (current_thread));
2781 if (ptrace (PTRACE_GETSIGINFO, lwpid_of (current_thread),
2782 (PTRACE_TYPE_ARG3) 0, &info) == 0)
2786 linux_resume_one_lwp (event_child, event_child->stepping,
2787 WSTOPSIG (w), info_p);
2788 return ignore_event (ourstatus);
2791 /* Note that all addresses are always "out of the step range" when
2792 there's no range to begin with. */
2793 in_step_range = lwp_in_step_range (event_child);
2795 /* If GDB wanted this thread to single step, and the thread is out
2796 of the step range, we always want to report the SIGTRAP, and let
2797 GDB handle it. Watchpoints should always be reported. So should
2798 signals we can't explain. A SIGTRAP we can't explain could be a
2799 GDB breakpoint --- we may or not support Z0 breakpoints. If we
2800 do, we're be able to handle GDB breakpoints on top of internal
2801 breakpoints, by handling the internal breakpoint and still
2802 reporting the event to GDB. If we don't, we're out of luck, GDB
2803 won't see the breakpoint hit. */
2804 report_to_gdb = (!maybe_internal_trap
2805 || (current_thread->last_resume_kind == resume_step
2807 || event_child->stop_reason == LWP_STOPPED_BY_WATCHPOINT
2808 || (!step_over_finished && !in_step_range
2809 && !bp_explains_trap && !trace_event)
2810 || (gdb_breakpoint_here (event_child->stop_pc)
2811 && gdb_condition_true_at_breakpoint (event_child->stop_pc)
2812 && gdb_no_commands_at_breakpoint (event_child->stop_pc)));
2814 run_breakpoint_commands (event_child->stop_pc);
2816 /* We found no reason GDB would want us to stop. We either hit one
2817 of our own breakpoints, or finished an internal step GDB
2818 shouldn't know about. */
2823 if (bp_explains_trap)
2824 debug_printf ("Hit a gdbserver breakpoint.\n");
2825 if (step_over_finished)
2826 debug_printf ("Step-over finished.\n");
2828 debug_printf ("Tracepoint event.\n");
2829 if (lwp_in_step_range (event_child))
2830 debug_printf ("Range stepping pc 0x%s [0x%s, 0x%s).\n",
2831 paddress (event_child->stop_pc),
2832 paddress (event_child->step_range_start),
2833 paddress (event_child->step_range_end));
2836 /* We're not reporting this breakpoint to GDB, so apply the
2837 decr_pc_after_break adjustment to the inferior's regcache
2840 if (the_low_target.set_pc != NULL)
2842 struct regcache *regcache
2843 = get_thread_regcache (current_thread, 1);
2844 (*the_low_target.set_pc) (regcache, event_child->stop_pc);
2847 /* We may have finished stepping over a breakpoint. If so,
2848 we've stopped and suspended all LWPs momentarily except the
2849 stepping one. This is where we resume them all again. We're
2850 going to keep waiting, so use proceed, which handles stepping
2851 over the next breakpoint. */
2853 debug_printf ("proceeding all threads.\n");
2855 if (step_over_finished)
2856 unsuspend_all_lwps (event_child);
2858 proceed_all_lwps ();
2859 return ignore_event (ourstatus);
2864 if (current_thread->last_resume_kind == resume_step)
2866 if (event_child->step_range_start == event_child->step_range_end)
2867 debug_printf ("GDB wanted to single-step, reporting event.\n");
2868 else if (!lwp_in_step_range (event_child))
2869 debug_printf ("Out of step range, reporting event.\n");
2871 if (event_child->stop_reason == LWP_STOPPED_BY_WATCHPOINT)
2872 debug_printf ("Stopped by watchpoint.\n");
2873 else if (gdb_breakpoint_here (event_child->stop_pc))
2874 debug_printf ("Stopped by GDB breakpoint.\n");
2876 debug_printf ("Hit a non-gdbserver trap event.\n");
2879 /* Alright, we're going to report a stop. */
2881 if (!stabilizing_threads)
2883 /* In all-stop, stop all threads. */
2885 stop_all_lwps (0, NULL);
2887 /* If we're not waiting for a specific LWP, choose an event LWP
2888 from among those that have had events. Giving equal priority
2889 to all LWPs that have had events helps prevent
2891 if (ptid_equal (ptid, minus_one_ptid))
2893 event_child->status_pending_p = 1;
2894 event_child->status_pending = w;
2896 select_event_lwp (&event_child);
2898 /* current_thread and event_child must stay in sync. */
2899 current_thread = get_lwp_thread (event_child);
2901 event_child->status_pending_p = 0;
2902 w = event_child->status_pending;
2905 if (step_over_finished)
2909 /* If we were doing a step-over, all other threads but
2910 the stepping one had been paused in start_step_over,
2911 with their suspend counts incremented. We don't want
2912 to do a full unstop/unpause, because we're in
2913 all-stop mode (so we want threads stopped), but we
2914 still need to unsuspend the other threads, to
2915 decrement their `suspended' count back. */
2916 unsuspend_all_lwps (event_child);
2920 /* If we just finished a step-over, then all threads had
2921 been momentarily paused. In all-stop, that's fine,
2922 we want threads stopped by now anyway. In non-stop,
2923 we need to re-resume threads that GDB wanted to be
2925 unstop_all_lwps (1, event_child);
2929 /* Stabilize threads (move out of jump pads). */
2931 stabilize_threads ();
2935 /* If we just finished a step-over, then all threads had been
2936 momentarily paused. In all-stop, that's fine, we want
2937 threads stopped by now anyway. In non-stop, we need to
2938 re-resume threads that GDB wanted to be running. */
2939 if (step_over_finished)
2940 unstop_all_lwps (1, event_child);
2943 ourstatus->kind = TARGET_WAITKIND_STOPPED;
2945 /* Now that we've selected our final event LWP, un-adjust its PC if
2946 it was a software breakpoint. */
2947 if (event_child->stop_reason == LWP_STOPPED_BY_SW_BREAKPOINT)
2949 int decr_pc = the_low_target.decr_pc_after_break;
2953 struct regcache *regcache
2954 = get_thread_regcache (current_thread, 1);
2955 (*the_low_target.set_pc) (regcache, event_child->stop_pc + decr_pc);
2959 if (current_thread->last_resume_kind == resume_stop
2960 && WSTOPSIG (w) == SIGSTOP)
2962 /* A thread that has been requested to stop by GDB with vCont;t,
2963 and it stopped cleanly, so report as SIG0. The use of
2964 SIGSTOP is an implementation detail. */
2965 ourstatus->value.sig = GDB_SIGNAL_0;
2967 else if (current_thread->last_resume_kind == resume_stop
2968 && WSTOPSIG (w) != SIGSTOP)
2970 /* A thread that has been requested to stop by GDB with vCont;t,
2971 but, it stopped for other reasons. */
2972 ourstatus->value.sig = gdb_signal_from_host (WSTOPSIG (w));
2976 ourstatus->value.sig = gdb_signal_from_host (WSTOPSIG (w));
2979 gdb_assert (ptid_equal (step_over_bkpt, null_ptid));
2983 debug_printf ("linux_wait_1 ret = %s, %d, %d\n",
2984 target_pid_to_str (ptid_of (current_thread)),
2985 ourstatus->kind, ourstatus->value.sig);
2989 return ptid_of (current_thread);
2992 /* Get rid of any pending event in the pipe. */
2994 async_file_flush (void)
3000 ret = read (linux_event_pipe[0], &buf, 1);
3001 while (ret >= 0 || (ret == -1 && errno == EINTR));
3004 /* Put something in the pipe, so the event loop wakes up. */
3006 async_file_mark (void)
3010 async_file_flush ();
3013 ret = write (linux_event_pipe[1], "+", 1);
3014 while (ret == 0 || (ret == -1 && errno == EINTR));
3016 /* Ignore EAGAIN. If the pipe is full, the event loop will already
3017 be awakened anyway. */
3021 linux_wait (ptid_t ptid,
3022 struct target_waitstatus *ourstatus, int target_options)
3026 /* Flush the async file first. */
3027 if (target_is_async_p ())
3028 async_file_flush ();
3032 event_ptid = linux_wait_1 (ptid, ourstatus, target_options);
3034 while ((target_options & TARGET_WNOHANG) == 0
3035 && ptid_equal (event_ptid, null_ptid)
3036 && ourstatus->kind == TARGET_WAITKIND_IGNORE);
3038 /* If at least one stop was reported, there may be more. A single
3039 SIGCHLD can signal more than one child stop. */
3040 if (target_is_async_p ()
3041 && (target_options & TARGET_WNOHANG) != 0
3042 && !ptid_equal (event_ptid, null_ptid))
3048 /* Send a signal to an LWP. */
3051 kill_lwp (unsigned long lwpid, int signo)
3053 /* Use tkill, if possible, in case we are using nptl threads. If tkill
3054 fails, then we are not using nptl threads and we should be using kill. */
3058 static int tkill_failed;
3065 ret = syscall (__NR_tkill, lwpid, signo);
3066 if (errno != ENOSYS)
3073 return kill (lwpid, signo);
3077 linux_stop_lwp (struct lwp_info *lwp)
3083 send_sigstop (struct lwp_info *lwp)
3087 pid = lwpid_of (get_lwp_thread (lwp));
3089 /* If we already have a pending stop signal for this process, don't
3091 if (lwp->stop_expected)
3094 debug_printf ("Have pending sigstop for lwp %d\n", pid);
3100 debug_printf ("Sending sigstop to lwp %d\n", pid);
3102 lwp->stop_expected = 1;
3103 kill_lwp (pid, SIGSTOP);
3107 send_sigstop_callback (struct inferior_list_entry *entry, void *except)
3109 struct thread_info *thread = (struct thread_info *) entry;
3110 struct lwp_info *lwp = get_thread_lwp (thread);
3112 /* Ignore EXCEPT. */
3123 /* Increment the suspend count of an LWP, and stop it, if not stopped
3126 suspend_and_send_sigstop_callback (struct inferior_list_entry *entry,
3129 struct thread_info *thread = (struct thread_info *) entry;
3130 struct lwp_info *lwp = get_thread_lwp (thread);
3132 /* Ignore EXCEPT. */
3138 return send_sigstop_callback (entry, except);
3142 mark_lwp_dead (struct lwp_info *lwp, int wstat)
3144 /* It's dead, really. */
3147 /* Store the exit status for later. */
3148 lwp->status_pending_p = 1;
3149 lwp->status_pending = wstat;
3151 /* Prevent trying to stop it. */
3154 /* No further stops are expected from a dead lwp. */
3155 lwp->stop_expected = 0;
3158 /* Wait for all children to stop for the SIGSTOPs we just queued. */
3161 wait_for_sigstop (void)
3163 struct thread_info *saved_thread;
3168 saved_thread = current_thread;
3169 if (saved_thread != NULL)
3170 saved_tid = saved_thread->entry.id;
3172 saved_tid = null_ptid; /* avoid bogus unused warning */
3175 debug_printf ("wait_for_sigstop: pulling events\n");
3177 /* Passing NULL_PTID as filter indicates we want all events to be
3178 left pending. Eventually this returns when there are no
3179 unwaited-for children left. */
3180 ret = linux_wait_for_event_filtered (minus_one_ptid, null_ptid,
3182 gdb_assert (ret == -1);
3184 if (saved_thread == NULL || linux_thread_alive (saved_tid))
3185 current_thread = saved_thread;
3189 debug_printf ("Previously current thread died.\n");
3193 /* We can't change the current inferior behind GDB's back,
3194 otherwise, a subsequent command may apply to the wrong
3196 current_thread = NULL;
3200 /* Set a valid thread as current. */
3201 set_desired_thread (0);
3206 /* Returns true if LWP ENTRY is stopped in a jump pad, and we can't
3207 move it out, because we need to report the stop event to GDB. For
3208 example, if the user puts a breakpoint in the jump pad, it's
3209 because she wants to debug it. */
3212 stuck_in_jump_pad_callback (struct inferior_list_entry *entry, void *data)
3214 struct thread_info *thread = (struct thread_info *) entry;
3215 struct lwp_info *lwp = get_thread_lwp (thread);
3217 gdb_assert (lwp->suspended == 0);
3218 gdb_assert (lwp->stopped);
3220 /* Allow debugging the jump pad, gdb_collect, etc.. */
3221 return (supports_fast_tracepoints ()
3222 && agent_loaded_p ()
3223 && (gdb_breakpoint_here (lwp->stop_pc)
3224 || lwp->stop_reason == LWP_STOPPED_BY_WATCHPOINT
3225 || thread->last_resume_kind == resume_step)
3226 && linux_fast_tracepoint_collecting (lwp, NULL));
3230 move_out_of_jump_pad_callback (struct inferior_list_entry *entry)
3232 struct thread_info *thread = (struct thread_info *) entry;
3233 struct lwp_info *lwp = get_thread_lwp (thread);
3236 gdb_assert (lwp->suspended == 0);
3237 gdb_assert (lwp->stopped);
3239 wstat = lwp->status_pending_p ? &lwp->status_pending : NULL;
3241 /* Allow debugging the jump pad, gdb_collect, etc. */
3242 if (!gdb_breakpoint_here (lwp->stop_pc)
3243 && lwp->stop_reason != LWP_STOPPED_BY_WATCHPOINT
3244 && thread->last_resume_kind != resume_step
3245 && maybe_move_out_of_jump_pad (lwp, wstat))
3248 debug_printf ("LWP %ld needs stabilizing (in jump pad)\n",
3253 lwp->status_pending_p = 0;
3254 enqueue_one_deferred_signal (lwp, wstat);
3257 debug_printf ("Signal %d for LWP %ld deferred "
3259 WSTOPSIG (*wstat), lwpid_of (thread));
3262 linux_resume_one_lwp (lwp, 0, 0, NULL);
3269 lwp_running (struct inferior_list_entry *entry, void *data)
3271 struct thread_info *thread = (struct thread_info *) entry;
3272 struct lwp_info *lwp = get_thread_lwp (thread);
3281 /* Stop all lwps that aren't stopped yet, except EXCEPT, if not NULL.
3282 If SUSPEND, then also increase the suspend count of every LWP,
3286 stop_all_lwps (int suspend, struct lwp_info *except)
3288 /* Should not be called recursively. */
3289 gdb_assert (stopping_threads == NOT_STOPPING_THREADS);
3294 debug_printf ("stop_all_lwps (%s, except=%s)\n",
3295 suspend ? "stop-and-suspend" : "stop",
3297 ? target_pid_to_str (ptid_of (get_lwp_thread (except)))
3301 stopping_threads = (suspend
3302 ? STOPPING_AND_SUSPENDING_THREADS
3303 : STOPPING_THREADS);
3306 find_inferior (&all_threads, suspend_and_send_sigstop_callback, except);
3308 find_inferior (&all_threads, send_sigstop_callback, except);
3309 wait_for_sigstop ();
3310 stopping_threads = NOT_STOPPING_THREADS;
3314 debug_printf ("stop_all_lwps done, setting stopping_threads "
3315 "back to !stopping\n");
3320 /* Resume execution of the inferior process.
3321 If STEP is nonzero, single-step it.
3322 If SIGNAL is nonzero, give it that signal. */
3325 linux_resume_one_lwp (struct lwp_info *lwp,
3326 int step, int signal, siginfo_t *info)
3328 struct thread_info *thread = get_lwp_thread (lwp);
3329 struct thread_info *saved_thread;
3330 int fast_tp_collecting;
3332 if (lwp->stopped == 0)
3335 fast_tp_collecting = lwp->collecting_fast_tracepoint;
3337 gdb_assert (!stabilizing_threads || fast_tp_collecting);
3339 /* Cancel actions that rely on GDB not changing the PC (e.g., the
3340 user used the "jump" command, or "set $pc = foo"). */
3341 if (lwp->stop_pc != get_pc (lwp))
3343 /* Collecting 'while-stepping' actions doesn't make sense
3345 release_while_stepping_state_list (thread);
3348 /* If we have pending signals or status, and a new signal, enqueue the
3349 signal. Also enqueue the signal if we are waiting to reinsert a
3350 breakpoint; it will be picked up again below. */
3352 && (lwp->status_pending_p
3353 || lwp->pending_signals != NULL
3354 || lwp->bp_reinsert != 0
3355 || fast_tp_collecting))
3357 struct pending_signals *p_sig;
3358 p_sig = xmalloc (sizeof (*p_sig));
3359 p_sig->prev = lwp->pending_signals;
3360 p_sig->signal = signal;
3362 memset (&p_sig->info, 0, sizeof (siginfo_t));
3364 memcpy (&p_sig->info, info, sizeof (siginfo_t));
3365 lwp->pending_signals = p_sig;
3368 if (lwp->status_pending_p)
3371 debug_printf ("Not resuming lwp %ld (%s, signal %d, stop %s);"
3372 " has pending status\n",
3373 lwpid_of (thread), step ? "step" : "continue", signal,
3374 lwp->stop_expected ? "expected" : "not expected");
3378 saved_thread = current_thread;
3379 current_thread = thread;
3382 debug_printf ("Resuming lwp %ld (%s, signal %d, stop %s)\n",
3383 lwpid_of (thread), step ? "step" : "continue", signal,
3384 lwp->stop_expected ? "expected" : "not expected");
3386 /* This bit needs some thinking about. If we get a signal that
3387 we must report while a single-step reinsert is still pending,
3388 we often end up resuming the thread. It might be better to
3389 (ew) allow a stack of pending events; then we could be sure that
3390 the reinsert happened right away and not lose any signals.
3392 Making this stack would also shrink the window in which breakpoints are
3393 uninserted (see comment in linux_wait_for_lwp) but not enough for
3394 complete correctness, so it won't solve that problem. It may be
3395 worthwhile just to solve this one, however. */
3396 if (lwp->bp_reinsert != 0)
3399 debug_printf (" pending reinsert at 0x%s\n",
3400 paddress (lwp->bp_reinsert));
3402 if (can_hardware_single_step ())
3404 if (fast_tp_collecting == 0)
3407 fprintf (stderr, "BAD - reinserting but not stepping.\n");
3409 fprintf (stderr, "BAD - reinserting and suspended(%d).\n",
3416 /* Postpone any pending signal. It was enqueued above. */
3420 if (fast_tp_collecting == 1)
3423 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
3424 " (exit-jump-pad-bkpt)\n",
3427 /* Postpone any pending signal. It was enqueued above. */
3430 else if (fast_tp_collecting == 2)
3433 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
3434 " single-stepping\n",
3437 if (can_hardware_single_step ())
3441 internal_error (__FILE__, __LINE__,
3442 "moving out of jump pad single-stepping"
3443 " not implemented on this target");
3446 /* Postpone any pending signal. It was enqueued above. */
3450 /* If we have while-stepping actions in this thread set it stepping.
3451 If we have a signal to deliver, it may or may not be set to
3452 SIG_IGN, we don't know. Assume so, and allow collecting
3453 while-stepping into a signal handler. A possible smart thing to
3454 do would be to set an internal breakpoint at the signal return
3455 address, continue, and carry on catching this while-stepping
3456 action only when that breakpoint is hit. A future
3458 if (thread->while_stepping != NULL
3459 && can_hardware_single_step ())
3462 debug_printf ("lwp %ld has a while-stepping action -> forcing step.\n",
3467 if (the_low_target.get_pc != NULL)
3469 struct regcache *regcache = get_thread_regcache (current_thread, 1);
3471 lwp->stop_pc = (*the_low_target.get_pc) (regcache);
3475 debug_printf (" %s from pc 0x%lx\n", step ? "step" : "continue",
3476 (long) lwp->stop_pc);
3480 /* If we have pending signals, consume one unless we are trying to
3481 reinsert a breakpoint or we're trying to finish a fast tracepoint
3483 if (lwp->pending_signals != NULL
3484 && lwp->bp_reinsert == 0
3485 && fast_tp_collecting == 0)
3487 struct pending_signals **p_sig;
3489 p_sig = &lwp->pending_signals;
3490 while ((*p_sig)->prev != NULL)
3491 p_sig = &(*p_sig)->prev;
3493 signal = (*p_sig)->signal;
3494 if ((*p_sig)->info.si_signo != 0)
3495 ptrace (PTRACE_SETSIGINFO, lwpid_of (thread), (PTRACE_TYPE_ARG3) 0,
3502 if (the_low_target.prepare_to_resume != NULL)
3503 the_low_target.prepare_to_resume (lwp);
3505 regcache_invalidate_thread (thread);
3508 lwp->stop_reason = LWP_STOPPED_BY_NO_REASON;
3509 lwp->stepping = step;
3510 ptrace (step ? PTRACE_SINGLESTEP : PTRACE_CONT, lwpid_of (thread),
3511 (PTRACE_TYPE_ARG3) 0,
3512 /* Coerce to a uintptr_t first to avoid potential gcc warning
3513 of coercing an 8 byte integer to a 4 byte pointer. */
3514 (PTRACE_TYPE_ARG4) (uintptr_t) signal);
3516 current_thread = saved_thread;
3519 /* ESRCH from ptrace either means that the thread was already
3520 running (an error) or that it is gone (a race condition). If
3521 it's gone, we will get a notification the next time we wait,
3522 so we can ignore the error. We could differentiate these
3523 two, but it's tricky without waiting; the thread still exists
3524 as a zombie, so sending it signal 0 would succeed. So just
3529 perror_with_name ("ptrace");
3533 struct thread_resume_array
3535 struct thread_resume *resume;
3539 /* This function is called once per thread via find_inferior.
3540 ARG is a pointer to a thread_resume_array struct.
3541 We look up the thread specified by ENTRY in ARG, and mark the thread
3542 with a pointer to the appropriate resume request.
3544 This algorithm is O(threads * resume elements), but resume elements
3545 is small (and will remain small at least until GDB supports thread
3549 linux_set_resume_request (struct inferior_list_entry *entry, void *arg)
3551 struct thread_info *thread = (struct thread_info *) entry;
3552 struct lwp_info *lwp = get_thread_lwp (thread);
3554 struct thread_resume_array *r;
3558 for (ndx = 0; ndx < r->n; ndx++)
3560 ptid_t ptid = r->resume[ndx].thread;
3561 if (ptid_equal (ptid, minus_one_ptid)
3562 || ptid_equal (ptid, entry->id)
3563 /* Handle both 'pPID' and 'pPID.-1' as meaning 'all threads
3565 || (ptid_get_pid (ptid) == pid_of (thread)
3566 && (ptid_is_pid (ptid)
3567 || ptid_get_lwp (ptid) == -1)))
3569 if (r->resume[ndx].kind == resume_stop
3570 && thread->last_resume_kind == resume_stop)
3573 debug_printf ("already %s LWP %ld at GDB's request\n",
3574 (thread->last_status.kind
3575 == TARGET_WAITKIND_STOPPED)
3583 lwp->resume = &r->resume[ndx];
3584 thread->last_resume_kind = lwp->resume->kind;
3586 lwp->step_range_start = lwp->resume->step_range_start;
3587 lwp->step_range_end = lwp->resume->step_range_end;
3589 /* If we had a deferred signal to report, dequeue one now.
3590 This can happen if LWP gets more than one signal while
3591 trying to get out of a jump pad. */
3593 && !lwp->status_pending_p
3594 && dequeue_one_deferred_signal (lwp, &lwp->status_pending))
3596 lwp->status_pending_p = 1;
3599 debug_printf ("Dequeueing deferred signal %d for LWP %ld, "
3600 "leaving status pending.\n",
3601 WSTOPSIG (lwp->status_pending),
3609 /* No resume action for this thread. */
3615 /* find_inferior callback for linux_resume.
3616 Set *FLAG_P if this lwp has an interesting status pending. */
3619 resume_status_pending_p (struct inferior_list_entry *entry, void *flag_p)
3621 struct thread_info *thread = (struct thread_info *) entry;
3622 struct lwp_info *lwp = get_thread_lwp (thread);
3624 /* LWPs which will not be resumed are not interesting, because
3625 we might not wait for them next time through linux_wait. */
3626 if (lwp->resume == NULL)
3629 if (thread_still_has_status_pending_p (thread))
3630 * (int *) flag_p = 1;
3635 /* Return 1 if this lwp that GDB wants running is stopped at an
3636 internal breakpoint that we need to step over. It assumes that any
3637 required STOP_PC adjustment has already been propagated to the
3638 inferior's regcache. */
3641 need_step_over_p (struct inferior_list_entry *entry, void *dummy)
3643 struct thread_info *thread = (struct thread_info *) entry;
3644 struct lwp_info *lwp = get_thread_lwp (thread);
3645 struct thread_info *saved_thread;
3648 /* LWPs which will not be resumed are not interesting, because we
3649 might not wait for them next time through linux_wait. */
3654 debug_printf ("Need step over [LWP %ld]? Ignoring, not stopped\n",
3659 if (thread->last_resume_kind == resume_stop)
3662 debug_printf ("Need step over [LWP %ld]? Ignoring, should remain"
3668 gdb_assert (lwp->suspended >= 0);
3673 debug_printf ("Need step over [LWP %ld]? Ignoring, suspended\n",
3678 if (!lwp->need_step_over)
3681 debug_printf ("Need step over [LWP %ld]? No\n", lwpid_of (thread));
3684 if (lwp->status_pending_p)
3687 debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
3693 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
3697 /* If the PC has changed since we stopped, then don't do anything,
3698 and let the breakpoint/tracepoint be hit. This happens if, for
3699 instance, GDB handled the decr_pc_after_break subtraction itself,
3700 GDB is OOL stepping this thread, or the user has issued a "jump"
3701 command, or poked thread's registers herself. */
3702 if (pc != lwp->stop_pc)
3705 debug_printf ("Need step over [LWP %ld]? Cancelling, PC was changed. "
3706 "Old stop_pc was 0x%s, PC is now 0x%s\n",
3708 paddress (lwp->stop_pc), paddress (pc));
3710 lwp->need_step_over = 0;
3714 saved_thread = current_thread;
3715 current_thread = thread;
3717 /* We can only step over breakpoints we know about. */
3718 if (breakpoint_here (pc) || fast_tracepoint_jump_here (pc))
3720 /* Don't step over a breakpoint that GDB expects to hit
3721 though. If the condition is being evaluated on the target's side
3722 and it evaluate to false, step over this breakpoint as well. */
3723 if (gdb_breakpoint_here (pc)
3724 && gdb_condition_true_at_breakpoint (pc)
3725 && gdb_no_commands_at_breakpoint (pc))
3728 debug_printf ("Need step over [LWP %ld]? yes, but found"
3729 " GDB breakpoint at 0x%s; skipping step over\n",
3730 lwpid_of (thread), paddress (pc));
3732 current_thread = saved_thread;
3738 debug_printf ("Need step over [LWP %ld]? yes, "
3739 "found breakpoint at 0x%s\n",
3740 lwpid_of (thread), paddress (pc));
3742 /* We've found an lwp that needs stepping over --- return 1 so
3743 that find_inferior stops looking. */
3744 current_thread = saved_thread;
3746 /* If the step over is cancelled, this is set again. */
3747 lwp->need_step_over = 0;
3752 current_thread = saved_thread;
3755 debug_printf ("Need step over [LWP %ld]? No, no breakpoint found"
3757 lwpid_of (thread), paddress (pc));
3762 /* Start a step-over operation on LWP. When LWP stopped at a
3763 breakpoint, to make progress, we need to remove the breakpoint out
3764 of the way. If we let other threads run while we do that, they may
3765 pass by the breakpoint location and miss hitting it. To avoid
3766 that, a step-over momentarily stops all threads while LWP is
3767 single-stepped while the breakpoint is temporarily uninserted from
3768 the inferior. When the single-step finishes, we reinsert the
3769 breakpoint, and let all threads that are supposed to be running,
3772 On targets that don't support hardware single-step, we don't
3773 currently support full software single-stepping. Instead, we only
3774 support stepping over the thread event breakpoint, by asking the
3775 low target where to place a reinsert breakpoint. Since this
3776 routine assumes the breakpoint being stepped over is a thread event
3777 breakpoint, it usually assumes the return address of the current
3778 function is a good enough place to set the reinsert breakpoint. */
3781 start_step_over (struct lwp_info *lwp)
3783 struct thread_info *thread = get_lwp_thread (lwp);
3784 struct thread_info *saved_thread;
3789 debug_printf ("Starting step-over on LWP %ld. Stopping all threads\n",
3792 stop_all_lwps (1, lwp);
3793 gdb_assert (lwp->suspended == 0);
3796 debug_printf ("Done stopping all threads for step-over.\n");
3798 /* Note, we should always reach here with an already adjusted PC,
3799 either by GDB (if we're resuming due to GDB's request), or by our
3800 caller, if we just finished handling an internal breakpoint GDB
3801 shouldn't care about. */
3804 saved_thread = current_thread;
3805 current_thread = thread;
3807 lwp->bp_reinsert = pc;
3808 uninsert_breakpoints_at (pc);
3809 uninsert_fast_tracepoint_jumps_at (pc);
3811 if (can_hardware_single_step ())
3817 CORE_ADDR raddr = (*the_low_target.breakpoint_reinsert_addr) ();
3818 set_reinsert_breakpoint (raddr);
3822 current_thread = saved_thread;
3824 linux_resume_one_lwp (lwp, step, 0, NULL);
3826 /* Require next event from this LWP. */
3827 step_over_bkpt = thread->entry.id;
3831 /* Finish a step-over. Reinsert the breakpoint we had uninserted in
3832 start_step_over, if still there, and delete any reinsert
3833 breakpoints we've set, on non hardware single-step targets. */
3836 finish_step_over (struct lwp_info *lwp)
3838 if (lwp->bp_reinsert != 0)
3841 debug_printf ("Finished step over.\n");
3843 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
3844 may be no breakpoint to reinsert there by now. */
3845 reinsert_breakpoints_at (lwp->bp_reinsert);
3846 reinsert_fast_tracepoint_jumps_at (lwp->bp_reinsert);
3848 lwp->bp_reinsert = 0;
3850 /* Delete any software-single-step reinsert breakpoints. No
3851 longer needed. We don't have to worry about other threads
3852 hitting this trap, and later not being able to explain it,
3853 because we were stepping over a breakpoint, and we hold all
3854 threads but LWP stopped while doing that. */
3855 if (!can_hardware_single_step ())
3856 delete_reinsert_breakpoints ();
3858 step_over_bkpt = null_ptid;
3865 /* This function is called once per thread. We check the thread's resume
3866 request, which will tell us whether to resume, step, or leave the thread
3867 stopped; and what signal, if any, it should be sent.
3869 For threads which we aren't explicitly told otherwise, we preserve
3870 the stepping flag; this is used for stepping over gdbserver-placed
3873 If pending_flags was set in any thread, we queue any needed
3874 signals, since we won't actually resume. We already have a pending
3875 event to report, so we don't need to preserve any step requests;
3876 they should be re-issued if necessary. */
3879 linux_resume_one_thread (struct inferior_list_entry *entry, void *arg)
3881 struct thread_info *thread = (struct thread_info *) entry;
3882 struct lwp_info *lwp = get_thread_lwp (thread);
3884 int leave_all_stopped = * (int *) arg;
3887 if (lwp->resume == NULL)
3890 if (lwp->resume->kind == resume_stop)
3893 debug_printf ("resume_stop request for LWP %ld\n", lwpid_of (thread));
3898 debug_printf ("stopping LWP %ld\n", lwpid_of (thread));
3900 /* Stop the thread, and wait for the event asynchronously,
3901 through the event loop. */
3907 debug_printf ("already stopped LWP %ld\n",
3910 /* The LWP may have been stopped in an internal event that
3911 was not meant to be notified back to GDB (e.g., gdbserver
3912 breakpoint), so we should be reporting a stop event in
3915 /* If the thread already has a pending SIGSTOP, this is a
3916 no-op. Otherwise, something later will presumably resume
3917 the thread and this will cause it to cancel any pending
3918 operation, due to last_resume_kind == resume_stop. If
3919 the thread already has a pending status to report, we
3920 will still report it the next time we wait - see
3921 status_pending_p_callback. */
3923 /* If we already have a pending signal to report, then
3924 there's no need to queue a SIGSTOP, as this means we're
3925 midway through moving the LWP out of the jumppad, and we
3926 will report the pending signal as soon as that is
3928 if (lwp->pending_signals_to_report == NULL)
3932 /* For stop requests, we're done. */
3934 thread->last_status.kind = TARGET_WAITKIND_IGNORE;
3938 /* If this thread which is about to be resumed has a pending status,
3939 then don't resume any threads - we can just report the pending
3940 status. Make sure to queue any signals that would otherwise be
3941 sent. In all-stop mode, we do this decision based on if *any*
3942 thread has a pending status. If there's a thread that needs the
3943 step-over-breakpoint dance, then don't resume any other thread
3944 but that particular one. */
3945 leave_pending = (lwp->status_pending_p || leave_all_stopped);
3950 debug_printf ("resuming LWP %ld\n", lwpid_of (thread));
3952 step = (lwp->resume->kind == resume_step);
3953 linux_resume_one_lwp (lwp, step, lwp->resume->sig, NULL);
3958 debug_printf ("leaving LWP %ld stopped\n", lwpid_of (thread));
3960 /* If we have a new signal, enqueue the signal. */
3961 if (lwp->resume->sig != 0)
3963 struct pending_signals *p_sig;
3964 p_sig = xmalloc (sizeof (*p_sig));
3965 p_sig->prev = lwp->pending_signals;
3966 p_sig->signal = lwp->resume->sig;
3967 memset (&p_sig->info, 0, sizeof (siginfo_t));
3969 /* If this is the same signal we were previously stopped by,
3970 make sure to queue its siginfo. We can ignore the return
3971 value of ptrace; if it fails, we'll skip
3972 PTRACE_SETSIGINFO. */
3973 if (WIFSTOPPED (lwp->last_status)
3974 && WSTOPSIG (lwp->last_status) == lwp->resume->sig)
3975 ptrace (PTRACE_GETSIGINFO, lwpid_of (thread), (PTRACE_TYPE_ARG3) 0,
3978 lwp->pending_signals = p_sig;
3982 thread->last_status.kind = TARGET_WAITKIND_IGNORE;
3988 linux_resume (struct thread_resume *resume_info, size_t n)
3990 struct thread_resume_array array = { resume_info, n };
3991 struct thread_info *need_step_over = NULL;
3993 int leave_all_stopped;
3998 debug_printf ("linux_resume:\n");
4001 find_inferior (&all_threads, linux_set_resume_request, &array);
4003 /* If there is a thread which would otherwise be resumed, which has
4004 a pending status, then don't resume any threads - we can just
4005 report the pending status. Make sure to queue any signals that
4006 would otherwise be sent. In non-stop mode, we'll apply this
4007 logic to each thread individually. We consume all pending events
4008 before considering to start a step-over (in all-stop). */
4011 find_inferior (&all_threads, resume_status_pending_p, &any_pending);
4013 /* If there is a thread which would otherwise be resumed, which is
4014 stopped at a breakpoint that needs stepping over, then don't
4015 resume any threads - have it step over the breakpoint with all
4016 other threads stopped, then resume all threads again. Make sure
4017 to queue any signals that would otherwise be delivered or
4019 if (!any_pending && supports_breakpoints ())
4021 = (struct thread_info *) find_inferior (&all_threads,
4022 need_step_over_p, NULL);
4024 leave_all_stopped = (need_step_over != NULL || any_pending);
4028 if (need_step_over != NULL)
4029 debug_printf ("Not resuming all, need step over\n");
4030 else if (any_pending)
4031 debug_printf ("Not resuming, all-stop and found "
4032 "an LWP with pending status\n");
4034 debug_printf ("Resuming, no pending status or step over needed\n");
4037 /* Even if we're leaving threads stopped, queue all signals we'd
4038 otherwise deliver. */
4039 find_inferior (&all_threads, linux_resume_one_thread, &leave_all_stopped);
4042 start_step_over (get_thread_lwp (need_step_over));
4046 debug_printf ("linux_resume done\n");
4051 /* This function is called once per thread. We check the thread's
4052 last resume request, which will tell us whether to resume, step, or
4053 leave the thread stopped. Any signal the client requested to be
4054 delivered has already been enqueued at this point.
4056 If any thread that GDB wants running is stopped at an internal
4057 breakpoint that needs stepping over, we start a step-over operation
4058 on that particular thread, and leave all others stopped. */
4061 proceed_one_lwp (struct inferior_list_entry *entry, void *except)
4063 struct thread_info *thread = (struct thread_info *) entry;
4064 struct lwp_info *lwp = get_thread_lwp (thread);
4071 debug_printf ("proceed_one_lwp: lwp %ld\n", lwpid_of (thread));
4076 debug_printf (" LWP %ld already running\n", lwpid_of (thread));
4080 if (thread->last_resume_kind == resume_stop
4081 && thread->last_status.kind != TARGET_WAITKIND_IGNORE)
4084 debug_printf (" client wants LWP to remain %ld stopped\n",
4089 if (lwp->status_pending_p)
4092 debug_printf (" LWP %ld has pending status, leaving stopped\n",
4097 gdb_assert (lwp->suspended >= 0);
4102 debug_printf (" LWP %ld is suspended\n", lwpid_of (thread));
4106 if (thread->last_resume_kind == resume_stop
4107 && lwp->pending_signals_to_report == NULL
4108 && lwp->collecting_fast_tracepoint == 0)
4110 /* We haven't reported this LWP as stopped yet (otherwise, the
4111 last_status.kind check above would catch it, and we wouldn't
4112 reach here. This LWP may have been momentarily paused by a
4113 stop_all_lwps call while handling for example, another LWP's
4114 step-over. In that case, the pending expected SIGSTOP signal
4115 that was queued at vCont;t handling time will have already
4116 been consumed by wait_for_sigstop, and so we need to requeue
4117 another one here. Note that if the LWP already has a SIGSTOP
4118 pending, this is a no-op. */
4121 debug_printf ("Client wants LWP %ld to stop. "
4122 "Making sure it has a SIGSTOP pending\n",
4128 step = thread->last_resume_kind == resume_step;
4129 linux_resume_one_lwp (lwp, step, 0, NULL);
4134 unsuspend_and_proceed_one_lwp (struct inferior_list_entry *entry, void *except)
4136 struct thread_info *thread = (struct thread_info *) entry;
4137 struct lwp_info *lwp = get_thread_lwp (thread);
4143 gdb_assert (lwp->suspended >= 0);
4145 return proceed_one_lwp (entry, except);
4148 /* When we finish a step-over, set threads running again. If there's
4149 another thread that may need a step-over, now's the time to start
4150 it. Eventually, we'll move all threads past their breakpoints. */
4153 proceed_all_lwps (void)
4155 struct thread_info *need_step_over;
4157 /* If there is a thread which would otherwise be resumed, which is
4158 stopped at a breakpoint that needs stepping over, then don't
4159 resume any threads - have it step over the breakpoint with all
4160 other threads stopped, then resume all threads again. */
4162 if (supports_breakpoints ())
4165 = (struct thread_info *) find_inferior (&all_threads,
4166 need_step_over_p, NULL);
4168 if (need_step_over != NULL)
4171 debug_printf ("proceed_all_lwps: found "
4172 "thread %ld needing a step-over\n",
4173 lwpid_of (need_step_over));
4175 start_step_over (get_thread_lwp (need_step_over));
4181 debug_printf ("Proceeding, no step-over needed\n");
4183 find_inferior (&all_threads, proceed_one_lwp, NULL);
4186 /* Stopped LWPs that the client wanted to be running, that don't have
4187 pending statuses, are set to run again, except for EXCEPT, if not
4188 NULL. This undoes a stop_all_lwps call. */
4191 unstop_all_lwps (int unsuspend, struct lwp_info *except)
4197 debug_printf ("unstopping all lwps, except=(LWP %ld)\n",
4198 lwpid_of (get_lwp_thread (except)));
4200 debug_printf ("unstopping all lwps\n");
4204 find_inferior (&all_threads, unsuspend_and_proceed_one_lwp, except);
4206 find_inferior (&all_threads, proceed_one_lwp, except);
4210 debug_printf ("unstop_all_lwps done\n");
4216 #ifdef HAVE_LINUX_REGSETS
4218 #define use_linux_regsets 1
4220 /* Returns true if REGSET has been disabled. */
4223 regset_disabled (struct regsets_info *info, struct regset_info *regset)
4225 return (info->disabled_regsets != NULL
4226 && info->disabled_regsets[regset - info->regsets]);
4229 /* Disable REGSET. */
4232 disable_regset (struct regsets_info *info, struct regset_info *regset)
4236 dr_offset = regset - info->regsets;
4237 if (info->disabled_regsets == NULL)
4238 info->disabled_regsets = xcalloc (1, info->num_regsets);
4239 info->disabled_regsets[dr_offset] = 1;
4243 regsets_fetch_inferior_registers (struct regsets_info *regsets_info,
4244 struct regcache *regcache)
4246 struct regset_info *regset;
4247 int saw_general_regs = 0;
4251 pid = lwpid_of (current_thread);
4252 for (regset = regsets_info->regsets; regset->size >= 0; regset++)
4257 if (regset->size == 0 || regset_disabled (regsets_info, regset))
4260 buf = xmalloc (regset->size);
4262 nt_type = regset->nt_type;
4266 iov.iov_len = regset->size;
4267 data = (void *) &iov;
4273 res = ptrace (regset->get_request, pid,
4274 (PTRACE_TYPE_ARG3) (long) nt_type, data);
4276 res = ptrace (regset->get_request, pid, data, nt_type);
4282 /* If we get EIO on a regset, do not try it again for
4283 this process mode. */
4284 disable_regset (regsets_info, regset);
4286 else if (errno == ENODATA)
4288 /* ENODATA may be returned if the regset is currently
4289 not "active". This can happen in normal operation,
4290 so suppress the warning in this case. */
4295 sprintf (s, "ptrace(regsets_fetch_inferior_registers) PID=%d",
4302 if (regset->type == GENERAL_REGS)
4303 saw_general_regs = 1;
4304 regset->store_function (regcache, buf);
4308 if (saw_general_regs)
4315 regsets_store_inferior_registers (struct regsets_info *regsets_info,
4316 struct regcache *regcache)
4318 struct regset_info *regset;
4319 int saw_general_regs = 0;
4323 pid = lwpid_of (current_thread);
4324 for (regset = regsets_info->regsets; regset->size >= 0; regset++)
4329 if (regset->size == 0 || regset_disabled (regsets_info, regset)
4330 || regset->fill_function == NULL)
4333 buf = xmalloc (regset->size);
4335 /* First fill the buffer with the current register set contents,
4336 in case there are any items in the kernel's regset that are
4337 not in gdbserver's regcache. */
4339 nt_type = regset->nt_type;
4343 iov.iov_len = regset->size;
4344 data = (void *) &iov;
4350 res = ptrace (regset->get_request, pid,
4351 (PTRACE_TYPE_ARG3) (long) nt_type, data);
4353 res = ptrace (regset->get_request, pid, data, nt_type);
4358 /* Then overlay our cached registers on that. */
4359 regset->fill_function (regcache, buf);
4361 /* Only now do we write the register set. */
4363 res = ptrace (regset->set_request, pid,
4364 (PTRACE_TYPE_ARG3) (long) nt_type, data);
4366 res = ptrace (regset->set_request, pid, data, nt_type);
4374 /* If we get EIO on a regset, do not try it again for
4375 this process mode. */
4376 disable_regset (regsets_info, regset);
4378 else if (errno == ESRCH)
4380 /* At this point, ESRCH should mean the process is
4381 already gone, in which case we simply ignore attempts
4382 to change its registers. See also the related
4383 comment in linux_resume_one_lwp. */
4389 perror ("Warning: ptrace(regsets_store_inferior_registers)");
4392 else if (regset->type == GENERAL_REGS)
4393 saw_general_regs = 1;
4396 if (saw_general_regs)
4402 #else /* !HAVE_LINUX_REGSETS */
4404 #define use_linux_regsets 0
4405 #define regsets_fetch_inferior_registers(regsets_info, regcache) 1
4406 #define regsets_store_inferior_registers(regsets_info, regcache) 1
4410 /* Return 1 if register REGNO is supported by one of the regset ptrace
4411 calls or 0 if it has to be transferred individually. */
4414 linux_register_in_regsets (const struct regs_info *regs_info, int regno)
4416 unsigned char mask = 1 << (regno % 8);
4417 size_t index = regno / 8;
4419 return (use_linux_regsets
4420 && (regs_info->regset_bitmap == NULL
4421 || (regs_info->regset_bitmap[index] & mask) != 0));
4424 #ifdef HAVE_LINUX_USRREGS
4427 register_addr (const struct usrregs_info *usrregs, int regnum)
4431 if (regnum < 0 || regnum >= usrregs->num_regs)
4432 error ("Invalid register number %d.", regnum);
4434 addr = usrregs->regmap[regnum];
4439 /* Fetch one register. */
4441 fetch_register (const struct usrregs_info *usrregs,
4442 struct regcache *regcache, int regno)
4449 if (regno >= usrregs->num_regs)
4451 if ((*the_low_target.cannot_fetch_register) (regno))
4454 regaddr = register_addr (usrregs, regno);
4458 size = ((register_size (regcache->tdesc, regno)
4459 + sizeof (PTRACE_XFER_TYPE) - 1)
4460 & -sizeof (PTRACE_XFER_TYPE));
4461 buf = alloca (size);
4463 pid = lwpid_of (current_thread);
4464 for (i = 0; i < size; i += sizeof (PTRACE_XFER_TYPE))
4467 *(PTRACE_XFER_TYPE *) (buf + i) =
4468 ptrace (PTRACE_PEEKUSER, pid,
4469 /* Coerce to a uintptr_t first to avoid potential gcc warning
4470 of coercing an 8 byte integer to a 4 byte pointer. */
4471 (PTRACE_TYPE_ARG3) (uintptr_t) regaddr, (PTRACE_TYPE_ARG4) 0);
4472 regaddr += sizeof (PTRACE_XFER_TYPE);
4474 error ("reading register %d: %s", regno, strerror (errno));
4477 if (the_low_target.supply_ptrace_register)
4478 the_low_target.supply_ptrace_register (regcache, regno, buf);
4480 supply_register (regcache, regno, buf);
4483 /* Store one register. */
4485 store_register (const struct usrregs_info *usrregs,
4486 struct regcache *regcache, int regno)
4493 if (regno >= usrregs->num_regs)
4495 if ((*the_low_target.cannot_store_register) (regno))
4498 regaddr = register_addr (usrregs, regno);
4502 size = ((register_size (regcache->tdesc, regno)
4503 + sizeof (PTRACE_XFER_TYPE) - 1)
4504 & -sizeof (PTRACE_XFER_TYPE));
4505 buf = alloca (size);
4506 memset (buf, 0, size);
4508 if (the_low_target.collect_ptrace_register)
4509 the_low_target.collect_ptrace_register (regcache, regno, buf);
4511 collect_register (regcache, regno, buf);
4513 pid = lwpid_of (current_thread);
4514 for (i = 0; i < size; i += sizeof (PTRACE_XFER_TYPE))
4517 ptrace (PTRACE_POKEUSER, pid,
4518 /* Coerce to a uintptr_t first to avoid potential gcc warning
4519 about coercing an 8 byte integer to a 4 byte pointer. */
4520 (PTRACE_TYPE_ARG3) (uintptr_t) regaddr,
4521 (PTRACE_TYPE_ARG4) *(PTRACE_XFER_TYPE *) (buf + i));
4524 /* At this point, ESRCH should mean the process is
4525 already gone, in which case we simply ignore attempts
4526 to change its registers. See also the related
4527 comment in linux_resume_one_lwp. */
4531 if ((*the_low_target.cannot_store_register) (regno) == 0)
4532 error ("writing register %d: %s", regno, strerror (errno));
4534 regaddr += sizeof (PTRACE_XFER_TYPE);
4538 /* Fetch all registers, or just one, from the child process.
4539 If REGNO is -1, do this for all registers, skipping any that are
4540 assumed to have been retrieved by regsets_fetch_inferior_registers,
4541 unless ALL is non-zero.
4542 Otherwise, REGNO specifies which register (so we can save time). */
4544 usr_fetch_inferior_registers (const struct regs_info *regs_info,
4545 struct regcache *regcache, int regno, int all)
4547 struct usrregs_info *usr = regs_info->usrregs;
4551 for (regno = 0; regno < usr->num_regs; regno++)
4552 if (all || !linux_register_in_regsets (regs_info, regno))
4553 fetch_register (usr, regcache, regno);
4556 fetch_register (usr, regcache, regno);
4559 /* Store our register values back into the inferior.
4560 If REGNO is -1, do this for all registers, skipping any that are
4561 assumed to have been saved by regsets_store_inferior_registers,
4562 unless ALL is non-zero.
4563 Otherwise, REGNO specifies which register (so we can save time). */
4565 usr_store_inferior_registers (const struct regs_info *regs_info,
4566 struct regcache *regcache, int regno, int all)
4568 struct usrregs_info *usr = regs_info->usrregs;
4572 for (regno = 0; regno < usr->num_regs; regno++)
4573 if (all || !linux_register_in_regsets (regs_info, regno))
4574 store_register (usr, regcache, regno);
4577 store_register (usr, regcache, regno);
4580 #else /* !HAVE_LINUX_USRREGS */
4582 #define usr_fetch_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
4583 #define usr_store_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
4589 linux_fetch_registers (struct regcache *regcache, int regno)
4593 const struct regs_info *regs_info = (*the_low_target.regs_info) ();
4597 if (the_low_target.fetch_register != NULL
4598 && regs_info->usrregs != NULL)
4599 for (regno = 0; regno < regs_info->usrregs->num_regs; regno++)
4600 (*the_low_target.fetch_register) (regcache, regno);
4602 all = regsets_fetch_inferior_registers (regs_info->regsets_info, regcache);
4603 if (regs_info->usrregs != NULL)
4604 usr_fetch_inferior_registers (regs_info, regcache, -1, all);
4608 if (the_low_target.fetch_register != NULL
4609 && (*the_low_target.fetch_register) (regcache, regno))
4612 use_regsets = linux_register_in_regsets (regs_info, regno);
4614 all = regsets_fetch_inferior_registers (regs_info->regsets_info,
4616 if ((!use_regsets || all) && regs_info->usrregs != NULL)
4617 usr_fetch_inferior_registers (regs_info, regcache, regno, 1);
4622 linux_store_registers (struct regcache *regcache, int regno)
4626 const struct regs_info *regs_info = (*the_low_target.regs_info) ();
4630 all = regsets_store_inferior_registers (regs_info->regsets_info,
4632 if (regs_info->usrregs != NULL)
4633 usr_store_inferior_registers (regs_info, regcache, regno, all);
4637 use_regsets = linux_register_in_regsets (regs_info, regno);
4639 all = regsets_store_inferior_registers (regs_info->regsets_info,
4641 if ((!use_regsets || all) && regs_info->usrregs != NULL)
4642 usr_store_inferior_registers (regs_info, regcache, regno, 1);
4647 /* Copy LEN bytes from inferior's memory starting at MEMADDR
4648 to debugger memory starting at MYADDR. */
4651 linux_read_memory (CORE_ADDR memaddr, unsigned char *myaddr, int len)
4653 int pid = lwpid_of (current_thread);
4654 register PTRACE_XFER_TYPE *buffer;
4655 register CORE_ADDR addr;
4662 /* Try using /proc. Don't bother for one word. */
4663 if (len >= 3 * sizeof (long))
4667 /* We could keep this file open and cache it - possibly one per
4668 thread. That requires some juggling, but is even faster. */
4669 sprintf (filename, "/proc/%d/mem", pid);
4670 fd = open (filename, O_RDONLY | O_LARGEFILE);
4674 /* If pread64 is available, use it. It's faster if the kernel
4675 supports it (only one syscall), and it's 64-bit safe even on
4676 32-bit platforms (for instance, SPARC debugging a SPARC64
4679 bytes = pread64 (fd, myaddr, len, memaddr);
4682 if (lseek (fd, memaddr, SEEK_SET) != -1)
4683 bytes = read (fd, myaddr, len);
4690 /* Some data was read, we'll try to get the rest with ptrace. */
4700 /* Round starting address down to longword boundary. */
4701 addr = memaddr & -(CORE_ADDR) sizeof (PTRACE_XFER_TYPE);
4702 /* Round ending address up; get number of longwords that makes. */
4703 count = ((((memaddr + len) - addr) + sizeof (PTRACE_XFER_TYPE) - 1)
4704 / sizeof (PTRACE_XFER_TYPE));
4705 /* Allocate buffer of that many longwords. */
4706 buffer = (PTRACE_XFER_TYPE *) alloca (count * sizeof (PTRACE_XFER_TYPE));
4708 /* Read all the longwords */
4710 for (i = 0; i < count; i++, addr += sizeof (PTRACE_XFER_TYPE))
4712 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
4713 about coercing an 8 byte integer to a 4 byte pointer. */
4714 buffer[i] = ptrace (PTRACE_PEEKTEXT, pid,
4715 (PTRACE_TYPE_ARG3) (uintptr_t) addr,
4716 (PTRACE_TYPE_ARG4) 0);
4722 /* Copy appropriate bytes out of the buffer. */
4725 i *= sizeof (PTRACE_XFER_TYPE);
4726 i -= memaddr & (sizeof (PTRACE_XFER_TYPE) - 1);
4728 (char *) buffer + (memaddr & (sizeof (PTRACE_XFER_TYPE) - 1)),
4735 /* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
4736 memory at MEMADDR. On failure (cannot write to the inferior)
4737 returns the value of errno. Always succeeds if LEN is zero. */
4740 linux_write_memory (CORE_ADDR memaddr, const unsigned char *myaddr, int len)
4743 /* Round starting address down to longword boundary. */
4744 register CORE_ADDR addr = memaddr & -(CORE_ADDR) sizeof (PTRACE_XFER_TYPE);
4745 /* Round ending address up; get number of longwords that makes. */
4747 = (((memaddr + len) - addr) + sizeof (PTRACE_XFER_TYPE) - 1)
4748 / sizeof (PTRACE_XFER_TYPE);
4750 /* Allocate buffer of that many longwords. */
4751 register PTRACE_XFER_TYPE *buffer = (PTRACE_XFER_TYPE *)
4752 alloca (count * sizeof (PTRACE_XFER_TYPE));
4754 int pid = lwpid_of (current_thread);
4758 /* Zero length write always succeeds. */
4764 /* Dump up to four bytes. */
4765 unsigned int val = * (unsigned int *) myaddr;
4771 val = val & 0xffffff;
4772 debug_printf ("Writing %0*x to 0x%08lx\n", 2 * ((len < 4) ? len : 4),
4773 val, (long)memaddr);
4776 /* Fill start and end extra bytes of buffer with existing memory data. */
4779 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
4780 about coercing an 8 byte integer to a 4 byte pointer. */
4781 buffer[0] = ptrace (PTRACE_PEEKTEXT, pid,
4782 (PTRACE_TYPE_ARG3) (uintptr_t) addr,
4783 (PTRACE_TYPE_ARG4) 0);
4791 = ptrace (PTRACE_PEEKTEXT, pid,
4792 /* Coerce to a uintptr_t first to avoid potential gcc warning
4793 about coercing an 8 byte integer to a 4 byte pointer. */
4794 (PTRACE_TYPE_ARG3) (uintptr_t) (addr + (count - 1)
4795 * sizeof (PTRACE_XFER_TYPE)),
4796 (PTRACE_TYPE_ARG4) 0);
4801 /* Copy data to be written over corresponding part of buffer. */
4803 memcpy ((char *) buffer + (memaddr & (sizeof (PTRACE_XFER_TYPE) - 1)),
4806 /* Write the entire buffer. */
4808 for (i = 0; i < count; i++, addr += sizeof (PTRACE_XFER_TYPE))
4811 ptrace (PTRACE_POKETEXT, pid,
4812 /* Coerce to a uintptr_t first to avoid potential gcc warning
4813 about coercing an 8 byte integer to a 4 byte pointer. */
4814 (PTRACE_TYPE_ARG3) (uintptr_t) addr,
4815 (PTRACE_TYPE_ARG4) buffer[i]);
4824 linux_look_up_symbols (void)
4826 #ifdef USE_THREAD_DB
4827 struct process_info *proc = current_process ();
4829 if (proc->private->thread_db != NULL)
4832 /* If the kernel supports tracing clones, then we don't need to
4833 use the magic thread event breakpoint to learn about
4835 thread_db_init (!linux_supports_traceclone ());
4840 linux_request_interrupt (void)
4842 extern unsigned long signal_pid;
4844 /* Send a SIGINT to the process group. This acts just like the user
4845 typed a ^C on the controlling terminal. */
4846 kill (-signal_pid, SIGINT);
4849 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
4850 to debugger memory starting at MYADDR. */
4853 linux_read_auxv (CORE_ADDR offset, unsigned char *myaddr, unsigned int len)
4855 char filename[PATH_MAX];
4857 int pid = lwpid_of (current_thread);
4859 xsnprintf (filename, sizeof filename, "/proc/%d/auxv", pid);
4861 fd = open (filename, O_RDONLY);
4865 if (offset != (CORE_ADDR) 0
4866 && lseek (fd, (off_t) offset, SEEK_SET) != (off_t) offset)
4869 n = read (fd, myaddr, len);
4876 /* These breakpoint and watchpoint related wrapper functions simply
4877 pass on the function call if the target has registered a
4878 corresponding function. */
4881 linux_supports_z_point_type (char z_type)
4883 return (the_low_target.supports_z_point_type != NULL
4884 && the_low_target.supports_z_point_type (z_type));
4888 linux_insert_point (enum raw_bkpt_type type, CORE_ADDR addr,
4889 int size, struct raw_breakpoint *bp)
4891 if (the_low_target.insert_point != NULL)
4892 return the_low_target.insert_point (type, addr, size, bp);
4894 /* Unsupported (see target.h). */
4899 linux_remove_point (enum raw_bkpt_type type, CORE_ADDR addr,
4900 int size, struct raw_breakpoint *bp)
4902 if (the_low_target.remove_point != NULL)
4903 return the_low_target.remove_point (type, addr, size, bp);
4905 /* Unsupported (see target.h). */
4910 linux_stopped_by_watchpoint (void)
4912 struct lwp_info *lwp = get_thread_lwp (current_thread);
4914 return lwp->stop_reason == LWP_STOPPED_BY_WATCHPOINT;
4918 linux_stopped_data_address (void)
4920 struct lwp_info *lwp = get_thread_lwp (current_thread);
4922 return lwp->stopped_data_address;
4925 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
4926 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
4927 && defined(PT_TEXT_END_ADDR)
4929 /* This is only used for targets that define PT_TEXT_ADDR,
4930 PT_DATA_ADDR and PT_TEXT_END_ADDR. If those are not defined, supposedly
4931 the target has different ways of acquiring this information, like
4934 /* Under uClinux, programs are loaded at non-zero offsets, which we need
4935 to tell gdb about. */
4938 linux_read_offsets (CORE_ADDR *text_p, CORE_ADDR *data_p)
4940 unsigned long text, text_end, data;
4941 int pid = lwpid_of (get_thread_lwp (current_thread));
4945 text = ptrace (PTRACE_PEEKUSER, pid, (PTRACE_TYPE_ARG3) PT_TEXT_ADDR,
4946 (PTRACE_TYPE_ARG4) 0);
4947 text_end = ptrace (PTRACE_PEEKUSER, pid, (PTRACE_TYPE_ARG3) PT_TEXT_END_ADDR,
4948 (PTRACE_TYPE_ARG4) 0);
4949 data = ptrace (PTRACE_PEEKUSER, pid, (PTRACE_TYPE_ARG3) PT_DATA_ADDR,
4950 (PTRACE_TYPE_ARG4) 0);
4954 /* Both text and data offsets produced at compile-time (and so
4955 used by gdb) are relative to the beginning of the program,
4956 with the data segment immediately following the text segment.
4957 However, the actual runtime layout in memory may put the data
4958 somewhere else, so when we send gdb a data base-address, we
4959 use the real data base address and subtract the compile-time
4960 data base-address from it (which is just the length of the
4961 text segment). BSS immediately follows data in both
4964 *data_p = data - (text_end - text);
4973 linux_qxfer_osdata (const char *annex,
4974 unsigned char *readbuf, unsigned const char *writebuf,
4975 CORE_ADDR offset, int len)
4977 return linux_common_xfer_osdata (annex, readbuf, offset, len);
4980 /* Convert a native/host siginfo object, into/from the siginfo in the
4981 layout of the inferiors' architecture. */
4984 siginfo_fixup (siginfo_t *siginfo, void *inf_siginfo, int direction)
4988 if (the_low_target.siginfo_fixup != NULL)
4989 done = the_low_target.siginfo_fixup (siginfo, inf_siginfo, direction);
4991 /* If there was no callback, or the callback didn't do anything,
4992 then just do a straight memcpy. */
4996 memcpy (siginfo, inf_siginfo, sizeof (siginfo_t));
4998 memcpy (inf_siginfo, siginfo, sizeof (siginfo_t));
5003 linux_xfer_siginfo (const char *annex, unsigned char *readbuf,
5004 unsigned const char *writebuf, CORE_ADDR offset, int len)
5008 char inf_siginfo[sizeof (siginfo_t)];
5010 if (current_thread == NULL)
5013 pid = lwpid_of (current_thread);
5016 debug_printf ("%s siginfo for lwp %d.\n",
5017 readbuf != NULL ? "Reading" : "Writing",
5020 if (offset >= sizeof (siginfo))
5023 if (ptrace (PTRACE_GETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo) != 0)
5026 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
5027 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
5028 inferior with a 64-bit GDBSERVER should look the same as debugging it
5029 with a 32-bit GDBSERVER, we need to convert it. */
5030 siginfo_fixup (&siginfo, inf_siginfo, 0);
5032 if (offset + len > sizeof (siginfo))
5033 len = sizeof (siginfo) - offset;
5035 if (readbuf != NULL)
5036 memcpy (readbuf, inf_siginfo + offset, len);
5039 memcpy (inf_siginfo + offset, writebuf, len);
5041 /* Convert back to ptrace layout before flushing it out. */
5042 siginfo_fixup (&siginfo, inf_siginfo, 1);
5044 if (ptrace (PTRACE_SETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo) != 0)
5051 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
5052 so we notice when children change state; as the handler for the
5053 sigsuspend in my_waitpid. */
5056 sigchld_handler (int signo)
5058 int old_errno = errno;
5064 /* fprintf is not async-signal-safe, so call write
5066 if (write (2, "sigchld_handler\n",
5067 sizeof ("sigchld_handler\n") - 1) < 0)
5068 break; /* just ignore */
5072 if (target_is_async_p ())
5073 async_file_mark (); /* trigger a linux_wait */
5079 linux_supports_non_stop (void)
5085 linux_async (int enable)
5087 int previous = target_is_async_p ();
5090 debug_printf ("linux_async (%d), previous=%d\n",
5093 if (previous != enable)
5096 sigemptyset (&mask);
5097 sigaddset (&mask, SIGCHLD);
5099 sigprocmask (SIG_BLOCK, &mask, NULL);
5103 if (pipe (linux_event_pipe) == -1)
5105 linux_event_pipe[0] = -1;
5106 linux_event_pipe[1] = -1;
5107 sigprocmask (SIG_UNBLOCK, &mask, NULL);
5109 warning ("creating event pipe failed.");
5113 fcntl (linux_event_pipe[0], F_SETFL, O_NONBLOCK);
5114 fcntl (linux_event_pipe[1], F_SETFL, O_NONBLOCK);
5116 /* Register the event loop handler. */
5117 add_file_handler (linux_event_pipe[0],
5118 handle_target_event, NULL);
5120 /* Always trigger a linux_wait. */
5125 delete_file_handler (linux_event_pipe[0]);
5127 close (linux_event_pipe[0]);
5128 close (linux_event_pipe[1]);
5129 linux_event_pipe[0] = -1;
5130 linux_event_pipe[1] = -1;
5133 sigprocmask (SIG_UNBLOCK, &mask, NULL);
5140 linux_start_non_stop (int nonstop)
5142 /* Register or unregister from event-loop accordingly. */
5143 linux_async (nonstop);
5145 if (target_is_async_p () != (nonstop != 0))
5152 linux_supports_multi_process (void)
5158 linux_supports_disable_randomization (void)
5160 #ifdef HAVE_PERSONALITY
5168 linux_supports_agent (void)
5174 linux_supports_range_stepping (void)
5176 if (*the_low_target.supports_range_stepping == NULL)
5179 return (*the_low_target.supports_range_stepping) ();
5182 /* Enumerate spufs IDs for process PID. */
5184 spu_enumerate_spu_ids (long pid, unsigned char *buf, CORE_ADDR offset, int len)
5190 struct dirent *entry;
5192 sprintf (path, "/proc/%ld/fd", pid);
5193 dir = opendir (path);
5198 while ((entry = readdir (dir)) != NULL)
5204 fd = atoi (entry->d_name);
5208 sprintf (path, "/proc/%ld/fd/%d", pid, fd);
5209 if (stat (path, &st) != 0)
5211 if (!S_ISDIR (st.st_mode))
5214 if (statfs (path, &stfs) != 0)
5216 if (stfs.f_type != SPUFS_MAGIC)
5219 if (pos >= offset && pos + 4 <= offset + len)
5221 *(unsigned int *)(buf + pos - offset) = fd;
5231 /* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
5232 object type, using the /proc file system. */
5234 linux_qxfer_spu (const char *annex, unsigned char *readbuf,
5235 unsigned const char *writebuf,
5236 CORE_ADDR offset, int len)
5238 long pid = lwpid_of (current_thread);
5243 if (!writebuf && !readbuf)
5251 return spu_enumerate_spu_ids (pid, readbuf, offset, len);
5254 sprintf (buf, "/proc/%ld/fd/%s", pid, annex);
5255 fd = open (buf, writebuf? O_WRONLY : O_RDONLY);
5260 && lseek (fd, (off_t) offset, SEEK_SET) != (off_t) offset)
5267 ret = write (fd, writebuf, (size_t) len);
5269 ret = read (fd, readbuf, (size_t) len);
5275 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
5276 struct target_loadseg
5278 /* Core address to which the segment is mapped. */
5280 /* VMA recorded in the program header. */
5282 /* Size of this segment in memory. */
5286 # if defined PT_GETDSBT
5287 struct target_loadmap
5289 /* Protocol version number, must be zero. */
5291 /* Pointer to the DSBT table, its size, and the DSBT index. */
5292 unsigned *dsbt_table;
5293 unsigned dsbt_size, dsbt_index;
5294 /* Number of segments in this map. */
5296 /* The actual memory map. */
5297 struct target_loadseg segs[/*nsegs*/];
5299 # define LINUX_LOADMAP PT_GETDSBT
5300 # define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
5301 # define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
5303 struct target_loadmap
5305 /* Protocol version number, must be zero. */
5307 /* Number of segments in this map. */
5309 /* The actual memory map. */
5310 struct target_loadseg segs[/*nsegs*/];
5312 # define LINUX_LOADMAP PTRACE_GETFDPIC
5313 # define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
5314 # define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
5318 linux_read_loadmap (const char *annex, CORE_ADDR offset,
5319 unsigned char *myaddr, unsigned int len)
5321 int pid = lwpid_of (current_thread);
5323 struct target_loadmap *data = NULL;
5324 unsigned int actual_length, copy_length;
5326 if (strcmp (annex, "exec") == 0)
5327 addr = (int) LINUX_LOADMAP_EXEC;
5328 else if (strcmp (annex, "interp") == 0)
5329 addr = (int) LINUX_LOADMAP_INTERP;
5333 if (ptrace (LINUX_LOADMAP, pid, addr, &data) != 0)
5339 actual_length = sizeof (struct target_loadmap)
5340 + sizeof (struct target_loadseg) * data->nsegs;
5342 if (offset < 0 || offset > actual_length)
5345 copy_length = actual_length - offset < len ? actual_length - offset : len;
5346 memcpy (myaddr, (char *) data + offset, copy_length);
5350 # define linux_read_loadmap NULL
5351 #endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
5354 linux_process_qsupported (const char *query)
5356 if (the_low_target.process_qsupported != NULL)
5357 the_low_target.process_qsupported (query);
5361 linux_supports_tracepoints (void)
5363 if (*the_low_target.supports_tracepoints == NULL)
5366 return (*the_low_target.supports_tracepoints) ();
5370 linux_read_pc (struct regcache *regcache)
5372 if (the_low_target.get_pc == NULL)
5375 return (*the_low_target.get_pc) (regcache);
5379 linux_write_pc (struct regcache *regcache, CORE_ADDR pc)
5381 gdb_assert (the_low_target.set_pc != NULL);
5383 (*the_low_target.set_pc) (regcache, pc);
5387 linux_thread_stopped (struct thread_info *thread)
5389 return get_thread_lwp (thread)->stopped;
5392 /* This exposes stop-all-threads functionality to other modules. */
5395 linux_pause_all (int freeze)
5397 stop_all_lwps (freeze, NULL);
5400 /* This exposes unstop-all-threads functionality to other gdbserver
5404 linux_unpause_all (int unfreeze)
5406 unstop_all_lwps (unfreeze, NULL);
5410 linux_prepare_to_access_memory (void)
5412 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
5415 linux_pause_all (1);
5420 linux_done_accessing_memory (void)
5422 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
5425 linux_unpause_all (1);
5429 linux_install_fast_tracepoint_jump_pad (CORE_ADDR tpoint, CORE_ADDR tpaddr,
5430 CORE_ADDR collector,
5433 CORE_ADDR *jump_entry,
5434 CORE_ADDR *trampoline,
5435 ULONGEST *trampoline_size,
5436 unsigned char *jjump_pad_insn,
5437 ULONGEST *jjump_pad_insn_size,
5438 CORE_ADDR *adjusted_insn_addr,
5439 CORE_ADDR *adjusted_insn_addr_end,
5442 return (*the_low_target.install_fast_tracepoint_jump_pad)
5443 (tpoint, tpaddr, collector, lockaddr, orig_size,
5444 jump_entry, trampoline, trampoline_size,
5445 jjump_pad_insn, jjump_pad_insn_size,
5446 adjusted_insn_addr, adjusted_insn_addr_end,
5450 static struct emit_ops *
5451 linux_emit_ops (void)
5453 if (the_low_target.emit_ops != NULL)
5454 return (*the_low_target.emit_ops) ();
5460 linux_get_min_fast_tracepoint_insn_len (void)
5462 return (*the_low_target.get_min_fast_tracepoint_insn_len) ();
5465 /* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
5468 get_phdr_phnum_from_proc_auxv (const int pid, const int is_elf64,
5469 CORE_ADDR *phdr_memaddr, int *num_phdr)
5471 char filename[PATH_MAX];
5473 const int auxv_size = is_elf64
5474 ? sizeof (Elf64_auxv_t) : sizeof (Elf32_auxv_t);
5475 char buf[sizeof (Elf64_auxv_t)]; /* The larger of the two. */
5477 xsnprintf (filename, sizeof filename, "/proc/%d/auxv", pid);
5479 fd = open (filename, O_RDONLY);
5485 while (read (fd, buf, auxv_size) == auxv_size
5486 && (*phdr_memaddr == 0 || *num_phdr == 0))
5490 Elf64_auxv_t *const aux = (Elf64_auxv_t *) buf;
5492 switch (aux->a_type)
5495 *phdr_memaddr = aux->a_un.a_val;
5498 *num_phdr = aux->a_un.a_val;
5504 Elf32_auxv_t *const aux = (Elf32_auxv_t *) buf;
5506 switch (aux->a_type)
5509 *phdr_memaddr = aux->a_un.a_val;
5512 *num_phdr = aux->a_un.a_val;
5520 if (*phdr_memaddr == 0 || *num_phdr == 0)
5522 warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
5523 "phdr_memaddr = %ld, phdr_num = %d",
5524 (long) *phdr_memaddr, *num_phdr);
5531 /* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
5534 get_dynamic (const int pid, const int is_elf64)
5536 CORE_ADDR phdr_memaddr, relocation;
5538 unsigned char *phdr_buf;
5539 const int phdr_size = is_elf64 ? sizeof (Elf64_Phdr) : sizeof (Elf32_Phdr);
5541 if (get_phdr_phnum_from_proc_auxv (pid, is_elf64, &phdr_memaddr, &num_phdr))
5544 gdb_assert (num_phdr < 100); /* Basic sanity check. */
5545 phdr_buf = alloca (num_phdr * phdr_size);
5547 if (linux_read_memory (phdr_memaddr, phdr_buf, num_phdr * phdr_size))
5550 /* Compute relocation: it is expected to be 0 for "regular" executables,
5551 non-zero for PIE ones. */
5553 for (i = 0; relocation == -1 && i < num_phdr; i++)
5556 Elf64_Phdr *const p = (Elf64_Phdr *) (phdr_buf + i * phdr_size);
5558 if (p->p_type == PT_PHDR)
5559 relocation = phdr_memaddr - p->p_vaddr;
5563 Elf32_Phdr *const p = (Elf32_Phdr *) (phdr_buf + i * phdr_size);
5565 if (p->p_type == PT_PHDR)
5566 relocation = phdr_memaddr - p->p_vaddr;
5569 if (relocation == -1)
5571 /* PT_PHDR is optional, but necessary for PIE in general. Fortunately
5572 any real world executables, including PIE executables, have always
5573 PT_PHDR present. PT_PHDR is not present in some shared libraries or
5574 in fpc (Free Pascal 2.4) binaries but neither of those have a need for
5575 or present DT_DEBUG anyway (fpc binaries are statically linked).
5577 Therefore if there exists DT_DEBUG there is always also PT_PHDR.
5579 GDB could find RELOCATION also from AT_ENTRY - e_entry. */
5584 for (i = 0; i < num_phdr; i++)
5588 Elf64_Phdr *const p = (Elf64_Phdr *) (phdr_buf + i * phdr_size);
5590 if (p->p_type == PT_DYNAMIC)
5591 return p->p_vaddr + relocation;
5595 Elf32_Phdr *const p = (Elf32_Phdr *) (phdr_buf + i * phdr_size);
5597 if (p->p_type == PT_DYNAMIC)
5598 return p->p_vaddr + relocation;
5605 /* Return &_r_debug in the inferior, or -1 if not present. Return value
5606 can be 0 if the inferior does not yet have the library list initialized.
5607 We look for DT_MIPS_RLD_MAP first. MIPS executables use this instead of
5608 DT_DEBUG, although they sometimes contain an unused DT_DEBUG entry too. */
5611 get_r_debug (const int pid, const int is_elf64)
5613 CORE_ADDR dynamic_memaddr;
5614 const int dyn_size = is_elf64 ? sizeof (Elf64_Dyn) : sizeof (Elf32_Dyn);
5615 unsigned char buf[sizeof (Elf64_Dyn)]; /* The larger of the two. */
5618 dynamic_memaddr = get_dynamic (pid, is_elf64);
5619 if (dynamic_memaddr == 0)
5622 while (linux_read_memory (dynamic_memaddr, buf, dyn_size) == 0)
5626 Elf64_Dyn *const dyn = (Elf64_Dyn *) buf;
5627 #ifdef DT_MIPS_RLD_MAP
5631 unsigned char buf[sizeof (Elf64_Xword)];
5635 if (dyn->d_tag == DT_MIPS_RLD_MAP)
5637 if (linux_read_memory (dyn->d_un.d_val,
5638 rld_map.buf, sizeof (rld_map.buf)) == 0)
5643 #endif /* DT_MIPS_RLD_MAP */
5645 if (dyn->d_tag == DT_DEBUG && map == -1)
5646 map = dyn->d_un.d_val;
5648 if (dyn->d_tag == DT_NULL)
5653 Elf32_Dyn *const dyn = (Elf32_Dyn *) buf;
5654 #ifdef DT_MIPS_RLD_MAP
5658 unsigned char buf[sizeof (Elf32_Word)];
5662 if (dyn->d_tag == DT_MIPS_RLD_MAP)
5664 if (linux_read_memory (dyn->d_un.d_val,
5665 rld_map.buf, sizeof (rld_map.buf)) == 0)
5670 #endif /* DT_MIPS_RLD_MAP */
5672 if (dyn->d_tag == DT_DEBUG && map == -1)
5673 map = dyn->d_un.d_val;
5675 if (dyn->d_tag == DT_NULL)
5679 dynamic_memaddr += dyn_size;
5685 /* Read one pointer from MEMADDR in the inferior. */
5688 read_one_ptr (CORE_ADDR memaddr, CORE_ADDR *ptr, int ptr_size)
5692 /* Go through a union so this works on either big or little endian
5693 hosts, when the inferior's pointer size is smaller than the size
5694 of CORE_ADDR. It is assumed the inferior's endianness is the
5695 same of the superior's. */
5698 CORE_ADDR core_addr;
5703 ret = linux_read_memory (memaddr, &addr.uc, ptr_size);
5706 if (ptr_size == sizeof (CORE_ADDR))
5707 *ptr = addr.core_addr;
5708 else if (ptr_size == sizeof (unsigned int))
5711 gdb_assert_not_reached ("unhandled pointer size");
5716 struct link_map_offsets
5718 /* Offset and size of r_debug.r_version. */
5719 int r_version_offset;
5721 /* Offset and size of r_debug.r_map. */
5724 /* Offset to l_addr field in struct link_map. */
5727 /* Offset to l_name field in struct link_map. */
5730 /* Offset to l_ld field in struct link_map. */
5733 /* Offset to l_next field in struct link_map. */
5736 /* Offset to l_prev field in struct link_map. */
5740 /* Construct qXfer:libraries-svr4:read reply. */
5743 linux_qxfer_libraries_svr4 (const char *annex, unsigned char *readbuf,
5744 unsigned const char *writebuf,
5745 CORE_ADDR offset, int len)
5748 unsigned document_len;
5749 struct process_info_private *const priv = current_process ()->private;
5750 char filename[PATH_MAX];
5753 static const struct link_map_offsets lmo_32bit_offsets =
5755 0, /* r_version offset. */
5756 4, /* r_debug.r_map offset. */
5757 0, /* l_addr offset in link_map. */
5758 4, /* l_name offset in link_map. */
5759 8, /* l_ld offset in link_map. */
5760 12, /* l_next offset in link_map. */
5761 16 /* l_prev offset in link_map. */
5764 static const struct link_map_offsets lmo_64bit_offsets =
5766 0, /* r_version offset. */
5767 8, /* r_debug.r_map offset. */
5768 0, /* l_addr offset in link_map. */
5769 8, /* l_name offset in link_map. */
5770 16, /* l_ld offset in link_map. */
5771 24, /* l_next offset in link_map. */
5772 32 /* l_prev offset in link_map. */
5774 const struct link_map_offsets *lmo;
5775 unsigned int machine;
5777 CORE_ADDR lm_addr = 0, lm_prev = 0;
5778 int allocated = 1024;
5780 CORE_ADDR l_name, l_addr, l_ld, l_next, l_prev;
5781 int header_done = 0;
5783 if (writebuf != NULL)
5785 if (readbuf == NULL)
5788 pid = lwpid_of (current_thread);
5789 xsnprintf (filename, sizeof filename, "/proc/%d/exe", pid);
5790 is_elf64 = elf_64_file_p (filename, &machine);
5791 lmo = is_elf64 ? &lmo_64bit_offsets : &lmo_32bit_offsets;
5792 ptr_size = is_elf64 ? 8 : 4;
5794 while (annex[0] != '\0')
5800 sep = strchr (annex, '=');
5805 if (len == 5 && strncmp (annex, "start", 5) == 0)
5807 else if (len == 4 && strncmp (annex, "prev", 4) == 0)
5811 annex = strchr (sep, ';');
5818 annex = decode_address_to_semicolon (addrp, sep + 1);
5825 if (priv->r_debug == 0)
5826 priv->r_debug = get_r_debug (pid, is_elf64);
5828 /* We failed to find DT_DEBUG. Such situation will not change
5829 for this inferior - do not retry it. Report it to GDB as
5830 E01, see for the reasons at the GDB solib-svr4.c side. */
5831 if (priv->r_debug == (CORE_ADDR) -1)
5834 if (priv->r_debug != 0)
5836 if (linux_read_memory (priv->r_debug + lmo->r_version_offset,
5837 (unsigned char *) &r_version,
5838 sizeof (r_version)) != 0
5841 warning ("unexpected r_debug version %d", r_version);
5843 else if (read_one_ptr (priv->r_debug + lmo->r_map_offset,
5844 &lm_addr, ptr_size) != 0)
5846 warning ("unable to read r_map from 0x%lx",
5847 (long) priv->r_debug + lmo->r_map_offset);
5852 document = xmalloc (allocated);
5853 strcpy (document, "<library-list-svr4 version=\"1.0\"");
5854 p = document + strlen (document);
5857 && read_one_ptr (lm_addr + lmo->l_name_offset,
5858 &l_name, ptr_size) == 0
5859 && read_one_ptr (lm_addr + lmo->l_addr_offset,
5860 &l_addr, ptr_size) == 0
5861 && read_one_ptr (lm_addr + lmo->l_ld_offset,
5862 &l_ld, ptr_size) == 0
5863 && read_one_ptr (lm_addr + lmo->l_prev_offset,
5864 &l_prev, ptr_size) == 0
5865 && read_one_ptr (lm_addr + lmo->l_next_offset,
5866 &l_next, ptr_size) == 0)
5868 unsigned char libname[PATH_MAX];
5870 if (lm_prev != l_prev)
5872 warning ("Corrupted shared library list: 0x%lx != 0x%lx",
5873 (long) lm_prev, (long) l_prev);
5877 /* Ignore the first entry even if it has valid name as the first entry
5878 corresponds to the main executable. The first entry should not be
5879 skipped if the dynamic loader was loaded late by a static executable
5880 (see solib-svr4.c parameter ignore_first). But in such case the main
5881 executable does not have PT_DYNAMIC present and this function already
5882 exited above due to failed get_r_debug. */
5885 sprintf (p, " main-lm=\"0x%lx\"", (unsigned long) lm_addr);
5890 /* Not checking for error because reading may stop before
5891 we've got PATH_MAX worth of characters. */
5893 linux_read_memory (l_name, libname, sizeof (libname) - 1);
5894 libname[sizeof (libname) - 1] = '\0';
5895 if (libname[0] != '\0')
5897 /* 6x the size for xml_escape_text below. */
5898 size_t len = 6 * strlen ((char *) libname);
5903 /* Terminate `<library-list-svr4'. */
5908 while (allocated < p - document + len + 200)
5910 /* Expand to guarantee sufficient storage. */
5911 uintptr_t document_len = p - document;
5913 document = xrealloc (document, 2 * allocated);
5915 p = document + document_len;
5918 name = xml_escape_text ((char *) libname);
5919 p += sprintf (p, "<library name=\"%s\" lm=\"0x%lx\" "
5920 "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
5921 name, (unsigned long) lm_addr,
5922 (unsigned long) l_addr, (unsigned long) l_ld);
5933 /* Empty list; terminate `<library-list-svr4'. */
5937 strcpy (p, "</library-list-svr4>");
5939 document_len = strlen (document);
5940 if (offset < document_len)
5941 document_len -= offset;
5944 if (len > document_len)
5947 memcpy (readbuf, document + offset, len);
5953 #ifdef HAVE_LINUX_BTRACE
5955 /* See to_enable_btrace target method. */
5957 static struct btrace_target_info *
5958 linux_low_enable_btrace (ptid_t ptid, const struct btrace_config *conf)
5960 struct btrace_target_info *tinfo;
5962 tinfo = linux_enable_btrace (ptid, conf);
5966 struct thread_info *thread = find_thread_ptid (ptid);
5967 struct regcache *regcache = get_thread_regcache (thread, 0);
5969 tinfo->ptr_bits = register_size (regcache->tdesc, 0) * 8;
5975 /* See to_disable_btrace target method. */
5978 linux_low_disable_btrace (struct btrace_target_info *tinfo)
5980 enum btrace_error err;
5982 err = linux_disable_btrace (tinfo);
5983 return (err == BTRACE_ERR_NONE ? 0 : -1);
5986 /* See to_read_btrace target method. */
5989 linux_low_read_btrace (struct btrace_target_info *tinfo, struct buffer *buffer,
5992 struct btrace_data btrace;
5993 struct btrace_block *block;
5994 enum btrace_error err;
5997 btrace_data_init (&btrace);
5999 err = linux_read_btrace (&btrace, tinfo, type);
6000 if (err != BTRACE_ERR_NONE)
6002 if (err == BTRACE_ERR_OVERFLOW)
6003 buffer_grow_str0 (buffer, "E.Overflow.");
6005 buffer_grow_str0 (buffer, "E.Generic Error.");
6007 btrace_data_fini (&btrace);
6011 switch (btrace.format)
6013 case BTRACE_FORMAT_NONE:
6014 buffer_grow_str0 (buffer, "E.No Trace.");
6017 case BTRACE_FORMAT_BTS:
6018 buffer_grow_str (buffer, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
6019 buffer_grow_str (buffer, "<btrace version=\"1.0\">\n");
6022 VEC_iterate (btrace_block_s, btrace.variant.bts.blocks, i, block);
6024 buffer_xml_printf (buffer, "<block begin=\"0x%s\" end=\"0x%s\"/>\n",
6025 paddress (block->begin), paddress (block->end));
6027 buffer_grow_str0 (buffer, "</btrace>\n");
6031 buffer_grow_str0 (buffer, "E.Unknown Trace Format.");
6033 btrace_data_fini (&btrace);
6037 btrace_data_fini (&btrace);
6041 /* See to_btrace_conf target method. */
6044 linux_low_btrace_conf (const struct btrace_target_info *tinfo,
6045 struct buffer *buffer)
6047 const struct btrace_config *conf;
6049 buffer_grow_str (buffer, "<!DOCTYPE btrace-conf SYSTEM \"btrace-conf.dtd\">\n");
6050 buffer_grow_str (buffer, "<btrace-conf version=\"1.0\">\n");
6052 conf = linux_btrace_conf (tinfo);
6055 switch (conf->format)
6057 case BTRACE_FORMAT_NONE:
6060 case BTRACE_FORMAT_BTS:
6061 buffer_xml_printf (buffer, "<bts");
6062 buffer_xml_printf (buffer, " size=\"0x%x\"", conf->bts.size);
6063 buffer_xml_printf (buffer, " />\n");
6068 buffer_grow_str0 (buffer, "</btrace-conf>\n");
6071 #endif /* HAVE_LINUX_BTRACE */
6073 static struct target_ops linux_target_ops = {
6074 linux_create_inferior,
6083 linux_fetch_registers,
6084 linux_store_registers,
6085 linux_prepare_to_access_memory,
6086 linux_done_accessing_memory,
6089 linux_look_up_symbols,
6090 linux_request_interrupt,
6092 linux_supports_z_point_type,
6095 linux_stopped_by_watchpoint,
6096 linux_stopped_data_address,
6097 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
6098 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
6099 && defined(PT_TEXT_END_ADDR)
6104 #ifdef USE_THREAD_DB
6105 thread_db_get_tls_address,
6110 hostio_last_error_from_errno,
6113 linux_supports_non_stop,
6115 linux_start_non_stop,
6116 linux_supports_multi_process,
6117 #ifdef USE_THREAD_DB
6118 thread_db_handle_monitor_command,
6122 linux_common_core_of_thread,
6124 linux_process_qsupported,
6125 linux_supports_tracepoints,
6128 linux_thread_stopped,
6132 linux_stabilize_threads,
6133 linux_install_fast_tracepoint_jump_pad,
6135 linux_supports_disable_randomization,
6136 linux_get_min_fast_tracepoint_insn_len,
6137 linux_qxfer_libraries_svr4,
6138 linux_supports_agent,
6139 #ifdef HAVE_LINUX_BTRACE
6140 linux_supports_btrace,
6141 linux_low_enable_btrace,
6142 linux_low_disable_btrace,
6143 linux_low_read_btrace,
6144 linux_low_btrace_conf,
6152 linux_supports_range_stepping,
6156 linux_init_signals ()
6158 /* FIXME drow/2002-06-09: As above, we should check with LinuxThreads
6159 to find what the cancel signal actually is. */
6160 #ifndef __ANDROID__ /* Bionic doesn't use SIGRTMIN the way glibc does. */
6161 signal (__SIGRTMIN+1, SIG_IGN);
6165 #ifdef HAVE_LINUX_REGSETS
6167 initialize_regsets_info (struct regsets_info *info)
6169 for (info->num_regsets = 0;
6170 info->regsets[info->num_regsets].size >= 0;
6171 info->num_regsets++)
6177 initialize_low (void)
6179 struct sigaction sigchld_action;
6180 memset (&sigchld_action, 0, sizeof (sigchld_action));
6181 set_target_ops (&linux_target_ops);
6182 set_breakpoint_data (the_low_target.breakpoint,
6183 the_low_target.breakpoint_len);
6184 linux_init_signals ();
6185 linux_ptrace_init_warnings ();
6187 sigchld_action.sa_handler = sigchld_handler;
6188 sigemptyset (&sigchld_action.sa_mask);
6189 sigchld_action.sa_flags = SA_RESTART;
6190 sigaction (SIGCHLD, &sigchld_action, NULL);
6192 initialize_low_arch ();