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. */
141 /* See nat/linux-nat.h. */
144 ptid_of_lwp (struct lwp_info *lwp)
146 return ptid_of (get_lwp_thread (lwp));
149 /* See nat/linux-nat.h. */
152 lwp_set_arch_private_info (struct lwp_info *lwp,
153 struct arch_lwp_info *info)
155 lwp->arch_private = info;
158 /* See nat/linux-nat.h. */
160 struct arch_lwp_info *
161 lwp_arch_private_info (struct lwp_info *lwp)
163 return lwp->arch_private;
166 /* See nat/linux-nat.h. */
169 lwp_is_stopped (struct lwp_info *lwp)
174 /* See nat/linux-nat.h. */
176 enum target_stop_reason
177 lwp_stop_reason (struct lwp_info *lwp)
179 return lwp->stop_reason;
182 /* A list of all unknown processes which receive stop signals. Some
183 other process will presumably claim each of these as forked
184 children momentarily. */
186 struct simple_pid_list
188 /* The process ID. */
191 /* The status as reported by waitpid. */
195 struct simple_pid_list *next;
197 struct simple_pid_list *stopped_pids;
199 /* Trivial list manipulation functions to keep track of a list of new
200 stopped processes. */
203 add_to_pid_list (struct simple_pid_list **listp, int pid, int status)
205 struct simple_pid_list *new_pid = xmalloc (sizeof (struct simple_pid_list));
208 new_pid->status = status;
209 new_pid->next = *listp;
214 pull_pid_from_list (struct simple_pid_list **listp, int pid, int *statusp)
216 struct simple_pid_list **p;
218 for (p = listp; *p != NULL; p = &(*p)->next)
219 if ((*p)->pid == pid)
221 struct simple_pid_list *next = (*p)->next;
223 *statusp = (*p)->status;
231 enum stopping_threads_kind
233 /* Not stopping threads presently. */
234 NOT_STOPPING_THREADS,
236 /* Stopping threads. */
239 /* Stopping and suspending threads. */
240 STOPPING_AND_SUSPENDING_THREADS
243 /* This is set while stop_all_lwps is in effect. */
244 enum stopping_threads_kind stopping_threads = NOT_STOPPING_THREADS;
246 /* FIXME make into a target method? */
247 int using_threads = 1;
249 /* True if we're presently stabilizing threads (moving them out of
251 static int stabilizing_threads;
253 static void linux_resume_one_lwp (struct lwp_info *lwp,
254 int step, int signal, siginfo_t *info);
255 static void linux_resume (struct thread_resume *resume_info, size_t n);
256 static void stop_all_lwps (int suspend, struct lwp_info *except);
257 static void unstop_all_lwps (int unsuspend, struct lwp_info *except);
258 static int linux_wait_for_event_filtered (ptid_t wait_ptid, ptid_t filter_ptid,
259 int *wstat, int options);
260 static int linux_wait_for_event (ptid_t ptid, int *wstat, int options);
261 static struct lwp_info *add_lwp (ptid_t ptid);
262 static int linux_stopped_by_watchpoint (void);
263 static void mark_lwp_dead (struct lwp_info *lwp, int wstat);
264 static void proceed_all_lwps (void);
265 static int finish_step_over (struct lwp_info *lwp);
266 static int kill_lwp (unsigned long lwpid, int signo);
268 /* When the event-loop is doing a step-over, this points at the thread
270 ptid_t step_over_bkpt;
272 /* True if the low target can hardware single-step. Such targets
273 don't need a BREAKPOINT_REINSERT_ADDR callback. */
276 can_hardware_single_step (void)
278 return (the_low_target.breakpoint_reinsert_addr == NULL);
281 /* True if the low target supports memory breakpoints. If so, we'll
282 have a GET_PC implementation. */
285 supports_breakpoints (void)
287 return (the_low_target.get_pc != NULL);
290 /* Returns true if this target can support fast tracepoints. This
291 does not mean that the in-process agent has been loaded in the
295 supports_fast_tracepoints (void)
297 return the_low_target.install_fast_tracepoint_jump_pad != NULL;
300 /* True if LWP is stopped in its stepping range. */
303 lwp_in_step_range (struct lwp_info *lwp)
305 CORE_ADDR pc = lwp->stop_pc;
307 return (pc >= lwp->step_range_start && pc < lwp->step_range_end);
310 struct pending_signals
314 struct pending_signals *prev;
317 /* The read/write ends of the pipe registered as waitable file in the
319 static int linux_event_pipe[2] = { -1, -1 };
321 /* True if we're currently in async mode. */
322 #define target_is_async_p() (linux_event_pipe[0] != -1)
324 static void send_sigstop (struct lwp_info *lwp);
325 static void wait_for_sigstop (void);
327 /* Return non-zero if HEADER is a 64-bit ELF file. */
330 elf_64_header_p (const Elf64_Ehdr *header, unsigned int *machine)
332 if (header->e_ident[EI_MAG0] == ELFMAG0
333 && header->e_ident[EI_MAG1] == ELFMAG1
334 && header->e_ident[EI_MAG2] == ELFMAG2
335 && header->e_ident[EI_MAG3] == ELFMAG3)
337 *machine = header->e_machine;
338 return header->e_ident[EI_CLASS] == ELFCLASS64;
345 /* Return non-zero if FILE is a 64-bit ELF file,
346 zero if the file is not a 64-bit ELF file,
347 and -1 if the file is not accessible or doesn't exist. */
350 elf_64_file_p (const char *file, unsigned int *machine)
355 fd = open (file, O_RDONLY);
359 if (read (fd, &header, sizeof (header)) != sizeof (header))
366 return elf_64_header_p (&header, machine);
369 /* Accepts an integer PID; Returns true if the executable PID is
370 running is a 64-bit ELF file.. */
373 linux_pid_exe_is_elf_64_file (int pid, unsigned int *machine)
377 sprintf (file, "/proc/%d/exe", pid);
378 return elf_64_file_p (file, machine);
382 delete_lwp (struct lwp_info *lwp)
384 struct thread_info *thr = get_lwp_thread (lwp);
387 debug_printf ("deleting %ld\n", lwpid_of (thr));
390 free (lwp->arch_private);
394 /* Add a process to the common process list, and set its private
397 static struct process_info *
398 linux_add_process (int pid, int attached)
400 struct process_info *proc;
402 proc = add_process (pid, attached);
403 proc->priv = xcalloc (1, sizeof (*proc->priv));
405 /* Set the arch when the first LWP stops. */
406 proc->priv->new_inferior = 1;
408 if (the_low_target.new_process != NULL)
409 proc->priv->arch_private = the_low_target.new_process ();
414 static CORE_ADDR get_pc (struct lwp_info *lwp);
416 /* Handle a GNU/Linux extended wait response. If we see a clone
417 event, we need to add the new LWP to our list (and not report the
418 trap to higher layers). */
421 handle_extended_wait (struct lwp_info *event_child, int wstat)
423 int event = linux_ptrace_get_extended_event (wstat);
424 struct thread_info *event_thr = get_lwp_thread (event_child);
425 struct lwp_info *new_lwp;
427 if (event == PTRACE_EVENT_CLONE)
430 unsigned long new_pid;
433 ptrace (PTRACE_GETEVENTMSG, lwpid_of (event_thr), (PTRACE_TYPE_ARG3) 0,
436 /* If we haven't already seen the new PID stop, wait for it now. */
437 if (!pull_pid_from_list (&stopped_pids, new_pid, &status))
439 /* The new child has a pending SIGSTOP. We can't affect it until it
440 hits the SIGSTOP, but we're already attached. */
442 ret = my_waitpid (new_pid, &status, __WALL);
445 perror_with_name ("waiting for new child");
446 else if (ret != new_pid)
447 warning ("wait returned unexpected PID %d", ret);
448 else if (!WIFSTOPPED (status))
449 warning ("wait returned unexpected status 0x%x", status);
453 debug_printf ("HEW: Got clone event "
454 "from LWP %ld, new child is LWP %ld\n",
455 lwpid_of (event_thr), new_pid);
457 ptid = ptid_build (pid_of (event_thr), new_pid, 0);
458 new_lwp = add_lwp (ptid);
460 /* Either we're going to immediately resume the new thread
461 or leave it stopped. linux_resume_one_lwp is a nop if it
462 thinks the thread is currently running, so set this first
463 before calling linux_resume_one_lwp. */
464 new_lwp->stopped = 1;
466 /* If we're suspending all threads, leave this one suspended
468 if (stopping_threads == STOPPING_AND_SUSPENDING_THREADS)
469 new_lwp->suspended = 1;
471 /* Normally we will get the pending SIGSTOP. But in some cases
472 we might get another signal delivered to the group first.
473 If we do get another signal, be sure not to lose it. */
474 if (WSTOPSIG (status) != SIGSTOP)
476 new_lwp->stop_expected = 1;
477 new_lwp->status_pending_p = 1;
478 new_lwp->status_pending = status;
483 /* Return the PC as read from the regcache of LWP, without any
487 get_pc (struct lwp_info *lwp)
489 struct thread_info *saved_thread;
490 struct regcache *regcache;
493 if (the_low_target.get_pc == NULL)
496 saved_thread = current_thread;
497 current_thread = get_lwp_thread (lwp);
499 regcache = get_thread_regcache (current_thread, 1);
500 pc = (*the_low_target.get_pc) (regcache);
503 debug_printf ("pc is 0x%lx\n", (long) pc);
505 current_thread = saved_thread;
509 /* This function should only be called if LWP got a SIGTRAP.
510 The SIGTRAP could mean several things.
512 On i386, where decr_pc_after_break is non-zero:
514 If we were single-stepping this process using PTRACE_SINGLESTEP, we
515 will get only the one SIGTRAP. The value of $eip will be the next
516 instruction. If the instruction we stepped over was a breakpoint,
517 we need to decrement the PC.
519 If we continue the process using PTRACE_CONT, we will get a
520 SIGTRAP when we hit a breakpoint. The value of $eip will be
521 the instruction after the breakpoint (i.e. needs to be
522 decremented). If we report the SIGTRAP to GDB, we must also
523 report the undecremented PC. If the breakpoint is removed, we
524 must resume at the decremented PC.
526 On a non-decr_pc_after_break machine with hardware or kernel
529 If we either single-step a breakpoint instruction, or continue and
530 hit a breakpoint instruction, our PC will point at the breakpoint
534 check_stopped_by_breakpoint (struct lwp_info *lwp)
537 CORE_ADDR sw_breakpoint_pc;
538 struct thread_info *saved_thread;
539 #if USE_SIGTRAP_SIGINFO
543 if (the_low_target.get_pc == NULL)
547 sw_breakpoint_pc = pc - the_low_target.decr_pc_after_break;
549 /* breakpoint_at reads from the current thread. */
550 saved_thread = current_thread;
551 current_thread = get_lwp_thread (lwp);
553 #if USE_SIGTRAP_SIGINFO
554 if (ptrace (PTRACE_GETSIGINFO, lwpid_of (current_thread),
555 (PTRACE_TYPE_ARG3) 0, &siginfo) == 0)
557 if (siginfo.si_signo == SIGTRAP)
559 if (siginfo.si_code == GDB_ARCH_TRAP_BRKPT)
563 struct thread_info *thr = get_lwp_thread (lwp);
565 debug_printf ("CSBB: %s stopped by software breakpoint\n",
566 target_pid_to_str (ptid_of (thr)));
569 /* Back up the PC if necessary. */
570 if (pc != sw_breakpoint_pc)
572 struct regcache *regcache
573 = get_thread_regcache (current_thread, 1);
574 (*the_low_target.set_pc) (regcache, sw_breakpoint_pc);
577 lwp->stop_pc = sw_breakpoint_pc;
578 lwp->stop_reason = TARGET_STOPPED_BY_SW_BREAKPOINT;
579 current_thread = saved_thread;
582 else if (siginfo.si_code == TRAP_HWBKPT)
586 struct thread_info *thr = get_lwp_thread (lwp);
588 debug_printf ("CSBB: %s stopped by hardware "
589 "breakpoint/watchpoint\n",
590 target_pid_to_str (ptid_of (thr)));
594 lwp->stop_reason = TARGET_STOPPED_BY_HW_BREAKPOINT;
595 current_thread = saved_thread;
598 else if (siginfo.si_code == TRAP_TRACE)
602 struct thread_info *thr = get_lwp_thread (lwp);
604 debug_printf ("CSBB: %s stopped by trace\n",
605 target_pid_to_str (ptid_of (thr)));
611 /* We may have just stepped a breakpoint instruction. E.g., in
612 non-stop mode, GDB first tells the thread A to step a range, and
613 then the user inserts a breakpoint inside the range. In that
614 case we need to report the breakpoint PC. */
615 if ((!lwp->stepping || lwp->stop_pc == sw_breakpoint_pc)
616 && (*the_low_target.breakpoint_at) (sw_breakpoint_pc))
620 struct thread_info *thr = get_lwp_thread (lwp);
622 debug_printf ("CSBB: %s stopped by software breakpoint\n",
623 target_pid_to_str (ptid_of (thr)));
626 /* Back up the PC if necessary. */
627 if (pc != sw_breakpoint_pc)
629 struct regcache *regcache
630 = get_thread_regcache (current_thread, 1);
631 (*the_low_target.set_pc) (regcache, sw_breakpoint_pc);
634 lwp->stop_pc = sw_breakpoint_pc;
635 lwp->stop_reason = TARGET_STOPPED_BY_SW_BREAKPOINT;
636 current_thread = saved_thread;
640 if (hardware_breakpoint_inserted_here (pc))
644 struct thread_info *thr = get_lwp_thread (lwp);
646 debug_printf ("CSBB: %s stopped by hardware breakpoint\n",
647 target_pid_to_str (ptid_of (thr)));
651 lwp->stop_reason = TARGET_STOPPED_BY_HW_BREAKPOINT;
652 current_thread = saved_thread;
657 current_thread = saved_thread;
661 static struct lwp_info *
662 add_lwp (ptid_t ptid)
664 struct lwp_info *lwp;
666 lwp = (struct lwp_info *) xmalloc (sizeof (*lwp));
667 memset (lwp, 0, sizeof (*lwp));
669 if (the_low_target.new_thread != NULL)
670 the_low_target.new_thread (lwp);
672 lwp->thread = add_thread (ptid, lwp);
677 /* Start an inferior process and returns its pid.
678 ALLARGS is a vector of program-name and args. */
681 linux_create_inferior (char *program, char **allargs)
683 struct lwp_info *new_lwp;
686 struct cleanup *restore_personality
687 = maybe_disable_address_space_randomization (disable_randomization);
689 #if defined(__UCLIBC__) && defined(HAS_NOMMU)
695 perror_with_name ("fork");
700 ptrace (PTRACE_TRACEME, 0, (PTRACE_TYPE_ARG3) 0, (PTRACE_TYPE_ARG4) 0);
702 #ifndef __ANDROID__ /* Bionic doesn't use SIGRTMIN the way glibc does. */
703 signal (__SIGRTMIN + 1, SIG_DFL);
708 /* If gdbserver is connected to gdb via stdio, redirect the inferior's
709 stdout to stderr so that inferior i/o doesn't corrupt the connection.
710 Also, redirect stdin to /dev/null. */
711 if (remote_connection_is_stdio ())
714 open ("/dev/null", O_RDONLY);
716 if (write (2, "stdin/stdout redirected\n",
717 sizeof ("stdin/stdout redirected\n") - 1) < 0)
719 /* Errors ignored. */;
723 execv (program, allargs);
725 execvp (program, allargs);
727 fprintf (stderr, "Cannot exec %s: %s.\n", program,
733 do_cleanups (restore_personality);
735 linux_add_process (pid, 0);
737 ptid = ptid_build (pid, pid, 0);
738 new_lwp = add_lwp (ptid);
739 new_lwp->must_set_ptrace_flags = 1;
744 /* Attach to an inferior process. Returns 0 on success, ERRNO on
748 linux_attach_lwp (ptid_t ptid)
750 struct lwp_info *new_lwp;
751 int lwpid = ptid_get_lwp (ptid);
753 if (ptrace (PTRACE_ATTACH, lwpid, (PTRACE_TYPE_ARG3) 0, (PTRACE_TYPE_ARG4) 0)
757 new_lwp = add_lwp (ptid);
759 /* We need to wait for SIGSTOP before being able to make the next
760 ptrace call on this LWP. */
761 new_lwp->must_set_ptrace_flags = 1;
763 if (linux_proc_pid_is_stopped (lwpid))
766 debug_printf ("Attached to a stopped process\n");
768 /* The process is definitely stopped. It is in a job control
769 stop, unless the kernel predates the TASK_STOPPED /
770 TASK_TRACED distinction, in which case it might be in a
771 ptrace stop. Make sure it is in a ptrace stop; from there we
772 can kill it, signal it, et cetera.
774 First make sure there is a pending SIGSTOP. Since we are
775 already attached, the process can not transition from stopped
776 to running without a PTRACE_CONT; so we know this signal will
777 go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
778 probably already in the queue (unless this kernel is old
779 enough to use TASK_STOPPED for ptrace stops); but since
780 SIGSTOP is not an RT signal, it can only be queued once. */
781 kill_lwp (lwpid, SIGSTOP);
783 /* Finally, resume the stopped process. This will deliver the
784 SIGSTOP (or a higher priority signal, just like normal
785 PTRACE_ATTACH), which we'll catch later on. */
786 ptrace (PTRACE_CONT, lwpid, (PTRACE_TYPE_ARG3) 0, (PTRACE_TYPE_ARG4) 0);
789 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
792 There are several cases to consider here:
794 1) gdbserver has already attached to the process and is being notified
795 of a new thread that is being created.
796 In this case we should ignore that SIGSTOP and resume the
797 process. This is handled below by setting stop_expected = 1,
798 and the fact that add_thread sets last_resume_kind ==
801 2) This is the first thread (the process thread), and we're attaching
802 to it via attach_inferior.
803 In this case we want the process thread to stop.
804 This is handled by having linux_attach set last_resume_kind ==
805 resume_stop after we return.
807 If the pid we are attaching to is also the tgid, we attach to and
808 stop all the existing threads. Otherwise, we attach to pid and
809 ignore any other threads in the same group as this pid.
811 3) GDB is connecting to gdbserver and is requesting an enumeration of all
813 In this case we want the thread to stop.
814 FIXME: This case is currently not properly handled.
815 We should wait for the SIGSTOP but don't. Things work apparently
816 because enough time passes between when we ptrace (ATTACH) and when
817 gdb makes the next ptrace call on the thread.
819 On the other hand, if we are currently trying to stop all threads, we
820 should treat the new thread as if we had sent it a SIGSTOP. This works
821 because we are guaranteed that the add_lwp call above added us to the
822 end of the list, and so the new thread has not yet reached
823 wait_for_sigstop (but will). */
824 new_lwp->stop_expected = 1;
829 /* Callback for linux_proc_attach_tgid_threads. Attach to PTID if not
830 already attached. Returns true if a new LWP is found, false
834 attach_proc_task_lwp_callback (ptid_t ptid)
836 /* Is this a new thread? */
837 if (find_thread_ptid (ptid) == NULL)
839 int lwpid = ptid_get_lwp (ptid);
843 debug_printf ("Found new lwp %d\n", lwpid);
845 err = linux_attach_lwp (ptid);
847 /* Be quiet if we simply raced with the thread exiting. EPERM
848 is returned if the thread's task still exists, and is marked
849 as exited or zombie, as well as other conditions, so in that
850 case, confirm the status in /proc/PID/status. */
852 || (err == EPERM && linux_proc_pid_is_gone (lwpid)))
856 debug_printf ("Cannot attach to lwp %d: "
857 "thread is gone (%d: %s)\n",
858 lwpid, err, strerror (err));
863 warning (_("Cannot attach to lwp %d: %s"),
865 linux_ptrace_attach_fail_reason_string (ptid, err));
873 /* Attach to PID. If PID is the tgid, attach to it and all
877 linux_attach (unsigned long pid)
879 ptid_t ptid = ptid_build (pid, pid, 0);
882 /* Attach to PID. We will check for other threads
884 err = linux_attach_lwp (ptid);
886 error ("Cannot attach to process %ld: %s",
887 pid, linux_ptrace_attach_fail_reason_string (ptid, err));
889 linux_add_process (pid, 1);
893 struct thread_info *thread;
895 /* Don't ignore the initial SIGSTOP if we just attached to this
896 process. It will be collected by wait shortly. */
897 thread = find_thread_ptid (ptid_build (pid, pid, 0));
898 thread->last_resume_kind = resume_stop;
901 /* We must attach to every LWP. If /proc is mounted, use that to
902 find them now. On the one hand, the inferior may be using raw
903 clone instead of using pthreads. On the other hand, even if it
904 is using pthreads, GDB may not be connected yet (thread_db needs
905 to do symbol lookups, through qSymbol). Also, thread_db walks
906 structures in the inferior's address space to find the list of
907 threads/LWPs, and those structures may well be corrupted. Note
908 that once thread_db is loaded, we'll still use it to list threads
909 and associate pthread info with each LWP. */
910 linux_proc_attach_tgid_threads (pid, attach_proc_task_lwp_callback);
921 second_thread_of_pid_p (struct inferior_list_entry *entry, void *args)
923 struct counter *counter = args;
925 if (ptid_get_pid (entry->id) == counter->pid)
927 if (++counter->count > 1)
935 last_thread_of_process_p (int pid)
937 struct counter counter = { pid , 0 };
939 return (find_inferior (&all_threads,
940 second_thread_of_pid_p, &counter) == NULL);
946 linux_kill_one_lwp (struct lwp_info *lwp)
948 struct thread_info *thr = get_lwp_thread (lwp);
949 int pid = lwpid_of (thr);
951 /* PTRACE_KILL is unreliable. After stepping into a signal handler,
952 there is no signal context, and ptrace(PTRACE_KILL) (or
953 ptrace(PTRACE_CONT, SIGKILL), pretty much the same) acts like
954 ptrace(CONT, pid, 0,0) and just resumes the tracee. A better
955 alternative is to kill with SIGKILL. We only need one SIGKILL
956 per process, not one for each thread. But since we still support
957 linuxthreads, and we also support debugging programs using raw
958 clone without CLONE_THREAD, we send one for each thread. For
959 years, we used PTRACE_KILL only, so we're being a bit paranoid
960 about some old kernels where PTRACE_KILL might work better
961 (dubious if there are any such, but that's why it's paranoia), so
962 we try SIGKILL first, PTRACE_KILL second, and so we're fine
966 kill_lwp (pid, SIGKILL);
969 int save_errno = errno;
971 debug_printf ("LKL: kill_lwp (SIGKILL) %s, 0, 0 (%s)\n",
972 target_pid_to_str (ptid_of (thr)),
973 save_errno ? strerror (save_errno) : "OK");
977 ptrace (PTRACE_KILL, pid, (PTRACE_TYPE_ARG3) 0, (PTRACE_TYPE_ARG4) 0);
980 int save_errno = errno;
982 debug_printf ("LKL: PTRACE_KILL %s, 0, 0 (%s)\n",
983 target_pid_to_str (ptid_of (thr)),
984 save_errno ? strerror (save_errno) : "OK");
988 /* Kill LWP and wait for it to die. */
991 kill_wait_lwp (struct lwp_info *lwp)
993 struct thread_info *thr = get_lwp_thread (lwp);
994 int pid = ptid_get_pid (ptid_of (thr));
995 int lwpid = ptid_get_lwp (ptid_of (thr));
1000 debug_printf ("kwl: killing lwp %d, for pid: %d\n", lwpid, pid);
1004 linux_kill_one_lwp (lwp);
1006 /* Make sure it died. Notes:
1008 - The loop is most likely unnecessary.
1010 - We don't use linux_wait_for_event as that could delete lwps
1011 while we're iterating over them. We're not interested in
1012 any pending status at this point, only in making sure all
1013 wait status on the kernel side are collected until the
1016 - We don't use __WALL here as the __WALL emulation relies on
1017 SIGCHLD, and killing a stopped process doesn't generate
1018 one, nor an exit status.
1020 res = my_waitpid (lwpid, &wstat, 0);
1021 if (res == -1 && errno == ECHILD)
1022 res = my_waitpid (lwpid, &wstat, __WCLONE);
1023 } while (res > 0 && WIFSTOPPED (wstat));
1025 gdb_assert (res > 0);
1028 /* Callback for `find_inferior'. Kills an lwp of a given process,
1029 except the leader. */
1032 kill_one_lwp_callback (struct inferior_list_entry *entry, void *args)
1034 struct thread_info *thread = (struct thread_info *) entry;
1035 struct lwp_info *lwp = get_thread_lwp (thread);
1036 int pid = * (int *) args;
1038 if (ptid_get_pid (entry->id) != pid)
1041 /* We avoid killing the first thread here, because of a Linux kernel (at
1042 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
1043 the children get a chance to be reaped, it will remain a zombie
1046 if (lwpid_of (thread) == pid)
1049 debug_printf ("lkop: is last of process %s\n",
1050 target_pid_to_str (entry->id));
1054 kill_wait_lwp (lwp);
1059 linux_kill (int pid)
1061 struct process_info *process;
1062 struct lwp_info *lwp;
1064 process = find_process_pid (pid);
1065 if (process == NULL)
1068 /* If we're killing a running inferior, make sure it is stopped
1069 first, as PTRACE_KILL will not work otherwise. */
1070 stop_all_lwps (0, NULL);
1072 find_inferior (&all_threads, kill_one_lwp_callback , &pid);
1074 /* See the comment in linux_kill_one_lwp. We did not kill the first
1075 thread in the list, so do so now. */
1076 lwp = find_lwp_pid (pid_to_ptid (pid));
1081 debug_printf ("lk_1: cannot find lwp for pid: %d\n",
1085 kill_wait_lwp (lwp);
1087 the_target->mourn (process);
1089 /* Since we presently can only stop all lwps of all processes, we
1090 need to unstop lwps of other processes. */
1091 unstop_all_lwps (0, NULL);
1095 /* Get pending signal of THREAD, for detaching purposes. This is the
1096 signal the thread last stopped for, which we need to deliver to the
1097 thread when detaching, otherwise, it'd be suppressed/lost. */
1100 get_detach_signal (struct thread_info *thread)
1102 enum gdb_signal signo = GDB_SIGNAL_0;
1104 struct lwp_info *lp = get_thread_lwp (thread);
1106 if (lp->status_pending_p)
1107 status = lp->status_pending;
1110 /* If the thread had been suspended by gdbserver, and it stopped
1111 cleanly, then it'll have stopped with SIGSTOP. But we don't
1112 want to deliver that SIGSTOP. */
1113 if (thread->last_status.kind != TARGET_WAITKIND_STOPPED
1114 || thread->last_status.value.sig == GDB_SIGNAL_0)
1117 /* Otherwise, we may need to deliver the signal we
1119 status = lp->last_status;
1122 if (!WIFSTOPPED (status))
1125 debug_printf ("GPS: lwp %s hasn't stopped: no pending signal\n",
1126 target_pid_to_str (ptid_of (thread)));
1130 /* Extended wait statuses aren't real SIGTRAPs. */
1131 if (WSTOPSIG (status) == SIGTRAP && linux_is_extended_waitstatus (status))
1134 debug_printf ("GPS: lwp %s had stopped with extended "
1135 "status: no pending signal\n",
1136 target_pid_to_str (ptid_of (thread)));
1140 signo = gdb_signal_from_host (WSTOPSIG (status));
1142 if (program_signals_p && !program_signals[signo])
1145 debug_printf ("GPS: lwp %s had signal %s, but it is in nopass state\n",
1146 target_pid_to_str (ptid_of (thread)),
1147 gdb_signal_to_string (signo));
1150 else if (!program_signals_p
1151 /* If we have no way to know which signals GDB does not
1152 want to have passed to the program, assume
1153 SIGTRAP/SIGINT, which is GDB's default. */
1154 && (signo == GDB_SIGNAL_TRAP || signo == GDB_SIGNAL_INT))
1157 debug_printf ("GPS: lwp %s had signal %s, "
1158 "but we don't know if we should pass it. "
1159 "Default to not.\n",
1160 target_pid_to_str (ptid_of (thread)),
1161 gdb_signal_to_string (signo));
1167 debug_printf ("GPS: lwp %s has pending signal %s: delivering it.\n",
1168 target_pid_to_str (ptid_of (thread)),
1169 gdb_signal_to_string (signo));
1171 return WSTOPSIG (status);
1176 linux_detach_one_lwp (struct inferior_list_entry *entry, void *args)
1178 struct thread_info *thread = (struct thread_info *) entry;
1179 struct lwp_info *lwp = get_thread_lwp (thread);
1180 int pid = * (int *) args;
1183 if (ptid_get_pid (entry->id) != pid)
1186 /* If there is a pending SIGSTOP, get rid of it. */
1187 if (lwp->stop_expected)
1190 debug_printf ("Sending SIGCONT to %s\n",
1191 target_pid_to_str (ptid_of (thread)));
1193 kill_lwp (lwpid_of (thread), SIGCONT);
1194 lwp->stop_expected = 0;
1197 /* Flush any pending changes to the process's registers. */
1198 regcache_invalidate_thread (thread);
1200 /* Pass on any pending signal for this thread. */
1201 sig = get_detach_signal (thread);
1203 /* Finally, let it resume. */
1204 if (the_low_target.prepare_to_resume != NULL)
1205 the_low_target.prepare_to_resume (lwp);
1206 if (ptrace (PTRACE_DETACH, lwpid_of (thread), (PTRACE_TYPE_ARG3) 0,
1207 (PTRACE_TYPE_ARG4) (long) sig) < 0)
1208 error (_("Can't detach %s: %s"),
1209 target_pid_to_str (ptid_of (thread)),
1217 linux_detach (int pid)
1219 struct process_info *process;
1221 process = find_process_pid (pid);
1222 if (process == NULL)
1225 /* Stop all threads before detaching. First, ptrace requires that
1226 the thread is stopped to sucessfully detach. Second, thread_db
1227 may need to uninstall thread event breakpoints from memory, which
1228 only works with a stopped process anyway. */
1229 stop_all_lwps (0, NULL);
1231 #ifdef USE_THREAD_DB
1232 thread_db_detach (process);
1235 /* Stabilize threads (move out of jump pads). */
1236 stabilize_threads ();
1238 find_inferior (&all_threads, linux_detach_one_lwp, &pid);
1240 the_target->mourn (process);
1242 /* Since we presently can only stop all lwps of all processes, we
1243 need to unstop lwps of other processes. */
1244 unstop_all_lwps (0, NULL);
1248 /* Remove all LWPs that belong to process PROC from the lwp list. */
1251 delete_lwp_callback (struct inferior_list_entry *entry, void *proc)
1253 struct thread_info *thread = (struct thread_info *) entry;
1254 struct lwp_info *lwp = get_thread_lwp (thread);
1255 struct process_info *process = proc;
1257 if (pid_of (thread) == pid_of (process))
1264 linux_mourn (struct process_info *process)
1266 struct process_info_private *priv;
1268 #ifdef USE_THREAD_DB
1269 thread_db_mourn (process);
1272 find_inferior (&all_threads, delete_lwp_callback, process);
1274 /* Freeing all private data. */
1275 priv = process->priv;
1276 free (priv->arch_private);
1278 process->priv = NULL;
1280 remove_process (process);
1284 linux_join (int pid)
1289 ret = my_waitpid (pid, &status, 0);
1290 if (WIFEXITED (status) || WIFSIGNALED (status))
1292 } while (ret != -1 || errno != ECHILD);
1295 /* Return nonzero if the given thread is still alive. */
1297 linux_thread_alive (ptid_t ptid)
1299 struct lwp_info *lwp = find_lwp_pid (ptid);
1301 /* We assume we always know if a thread exits. If a whole process
1302 exited but we still haven't been able to report it to GDB, we'll
1303 hold on to the last lwp of the dead process. */
1310 /* Return 1 if this lwp still has an interesting status pending. If
1311 not (e.g., it had stopped for a breakpoint that is gone), return
1315 thread_still_has_status_pending_p (struct thread_info *thread)
1317 struct lwp_info *lp = get_thread_lwp (thread);
1319 if (!lp->status_pending_p)
1322 /* If we got a `vCont;t', but we haven't reported a stop yet, do
1323 report any status pending the LWP may have. */
1324 if (thread->last_resume_kind == resume_stop
1325 && thread->last_status.kind != TARGET_WAITKIND_IGNORE)
1328 if (thread->last_resume_kind != resume_stop
1329 && (lp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT
1330 || lp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT))
1332 struct thread_info *saved_thread;
1336 gdb_assert (lp->last_status != 0);
1340 saved_thread = current_thread;
1341 current_thread = thread;
1343 if (pc != lp->stop_pc)
1346 debug_printf ("PC of %ld changed\n",
1351 #if !USE_SIGTRAP_SIGINFO
1352 else if (lp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT
1353 && !(*the_low_target.breakpoint_at) (pc))
1356 debug_printf ("previous SW breakpoint of %ld gone\n",
1360 else if (lp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT
1361 && !hardware_breakpoint_inserted_here (pc))
1364 debug_printf ("previous HW breakpoint of %ld gone\n",
1370 current_thread = saved_thread;
1375 debug_printf ("discarding pending breakpoint status\n");
1376 lp->status_pending_p = 0;
1384 /* Return 1 if this lwp has an interesting status pending. */
1386 status_pending_p_callback (struct inferior_list_entry *entry, void *arg)
1388 struct thread_info *thread = (struct thread_info *) entry;
1389 struct lwp_info *lp = get_thread_lwp (thread);
1390 ptid_t ptid = * (ptid_t *) arg;
1392 /* Check if we're only interested in events from a specific process
1393 or a specific LWP. */
1394 if (!ptid_match (ptid_of (thread), ptid))
1397 if (lp->status_pending_p
1398 && !thread_still_has_status_pending_p (thread))
1400 linux_resume_one_lwp (lp, lp->stepping, GDB_SIGNAL_0, NULL);
1404 return lp->status_pending_p;
1408 same_lwp (struct inferior_list_entry *entry, void *data)
1410 ptid_t ptid = *(ptid_t *) data;
1413 if (ptid_get_lwp (ptid) != 0)
1414 lwp = ptid_get_lwp (ptid);
1416 lwp = ptid_get_pid (ptid);
1418 if (ptid_get_lwp (entry->id) == lwp)
1425 find_lwp_pid (ptid_t ptid)
1427 struct inferior_list_entry *thread
1428 = find_inferior (&all_threads, same_lwp, &ptid);
1433 return get_thread_lwp ((struct thread_info *) thread);
1436 /* Return the number of known LWPs in the tgid given by PID. */
1441 struct inferior_list_entry *inf, *tmp;
1444 ALL_INFERIORS (&all_threads, inf, tmp)
1446 if (ptid_get_pid (inf->id) == pid)
1453 /* The arguments passed to iterate_over_lwps. */
1455 struct iterate_over_lwps_args
1457 /* The FILTER argument passed to iterate_over_lwps. */
1460 /* The CALLBACK argument passed to iterate_over_lwps. */
1461 iterate_over_lwps_ftype *callback;
1463 /* The DATA argument passed to iterate_over_lwps. */
1467 /* Callback for find_inferior used by iterate_over_lwps to filter
1468 calls to the callback supplied to that function. Returning a
1469 nonzero value causes find_inferiors to stop iterating and return
1470 the current inferior_list_entry. Returning zero indicates that
1471 find_inferiors should continue iterating. */
1474 iterate_over_lwps_filter (struct inferior_list_entry *entry, void *args_p)
1476 struct iterate_over_lwps_args *args
1477 = (struct iterate_over_lwps_args *) args_p;
1479 if (ptid_match (entry->id, args->filter))
1481 struct thread_info *thr = (struct thread_info *) entry;
1482 struct lwp_info *lwp = get_thread_lwp (thr);
1484 return (*args->callback) (lwp, args->data);
1490 /* See nat/linux-nat.h. */
1493 iterate_over_lwps (ptid_t filter,
1494 iterate_over_lwps_ftype callback,
1497 struct iterate_over_lwps_args args = {filter, callback, data};
1498 struct inferior_list_entry *entry;
1500 entry = find_inferior (&all_threads, iterate_over_lwps_filter, &args);
1504 return get_thread_lwp ((struct thread_info *) entry);
1507 /* Detect zombie thread group leaders, and "exit" them. We can't reap
1508 their exits until all other threads in the group have exited. */
1511 check_zombie_leaders (void)
1513 struct process_info *proc, *tmp;
1515 ALL_PROCESSES (proc, tmp)
1517 pid_t leader_pid = pid_of (proc);
1518 struct lwp_info *leader_lp;
1520 leader_lp = find_lwp_pid (pid_to_ptid (leader_pid));
1523 debug_printf ("leader_pid=%d, leader_lp!=NULL=%d, "
1524 "num_lwps=%d, zombie=%d\n",
1525 leader_pid, leader_lp!= NULL, num_lwps (leader_pid),
1526 linux_proc_pid_is_zombie (leader_pid));
1528 if (leader_lp != NULL
1529 /* Check if there are other threads in the group, as we may
1530 have raced with the inferior simply exiting. */
1531 && !last_thread_of_process_p (leader_pid)
1532 && linux_proc_pid_is_zombie (leader_pid))
1534 /* A leader zombie can mean one of two things:
1536 - It exited, and there's an exit status pending
1537 available, or only the leader exited (not the whole
1538 program). In the latter case, we can't waitpid the
1539 leader's exit status until all other threads are gone.
1541 - There are 3 or more threads in the group, and a thread
1542 other than the leader exec'd. On an exec, the Linux
1543 kernel destroys all other threads (except the execing
1544 one) in the thread group, and resets the execing thread's
1545 tid to the tgid. No exit notification is sent for the
1546 execing thread -- from the ptracer's perspective, it
1547 appears as though the execing thread just vanishes.
1548 Until we reap all other threads except the leader and the
1549 execing thread, the leader will be zombie, and the
1550 execing thread will be in `D (disc sleep)'. As soon as
1551 all other threads are reaped, the execing thread changes
1552 it's tid to the tgid, and the previous (zombie) leader
1553 vanishes, giving place to the "new" leader. We could try
1554 distinguishing the exit and exec cases, by waiting once
1555 more, and seeing if something comes out, but it doesn't
1556 sound useful. The previous leader _does_ go away, and
1557 we'll re-add the new one once we see the exec event
1558 (which is just the same as what would happen if the
1559 previous leader did exit voluntarily before some other
1564 "CZL: Thread group leader %d zombie "
1565 "(it exited, or another thread execd).\n",
1568 delete_lwp (leader_lp);
1573 /* Callback for `find_inferior'. Returns the first LWP that is not
1574 stopped. ARG is a PTID filter. */
1577 not_stopped_callback (struct inferior_list_entry *entry, void *arg)
1579 struct thread_info *thr = (struct thread_info *) entry;
1580 struct lwp_info *lwp;
1581 ptid_t filter = *(ptid_t *) arg;
1583 if (!ptid_match (ptid_of (thr), filter))
1586 lwp = get_thread_lwp (thr);
1593 /* This function should only be called if the LWP got a SIGTRAP.
1595 Handle any tracepoint steps or hits. Return true if a tracepoint
1596 event was handled, 0 otherwise. */
1599 handle_tracepoints (struct lwp_info *lwp)
1601 struct thread_info *tinfo = get_lwp_thread (lwp);
1602 int tpoint_related_event = 0;
1604 gdb_assert (lwp->suspended == 0);
1606 /* If this tracepoint hit causes a tracing stop, we'll immediately
1607 uninsert tracepoints. To do this, we temporarily pause all
1608 threads, unpatch away, and then unpause threads. We need to make
1609 sure the unpausing doesn't resume LWP too. */
1612 /* And we need to be sure that any all-threads-stopping doesn't try
1613 to move threads out of the jump pads, as it could deadlock the
1614 inferior (LWP could be in the jump pad, maybe even holding the
1617 /* Do any necessary step collect actions. */
1618 tpoint_related_event |= tracepoint_finished_step (tinfo, lwp->stop_pc);
1620 tpoint_related_event |= handle_tracepoint_bkpts (tinfo, lwp->stop_pc);
1622 /* See if we just hit a tracepoint and do its main collect
1624 tpoint_related_event |= tracepoint_was_hit (tinfo, lwp->stop_pc);
1628 gdb_assert (lwp->suspended == 0);
1629 gdb_assert (!stabilizing_threads || lwp->collecting_fast_tracepoint);
1631 if (tpoint_related_event)
1634 debug_printf ("got a tracepoint event\n");
1641 /* Convenience wrapper. Returns true if LWP is presently collecting a
1645 linux_fast_tracepoint_collecting (struct lwp_info *lwp,
1646 struct fast_tpoint_collect_status *status)
1648 CORE_ADDR thread_area;
1649 struct thread_info *thread = get_lwp_thread (lwp);
1651 if (the_low_target.get_thread_area == NULL)
1654 /* Get the thread area address. This is used to recognize which
1655 thread is which when tracing with the in-process agent library.
1656 We don't read anything from the address, and treat it as opaque;
1657 it's the address itself that we assume is unique per-thread. */
1658 if ((*the_low_target.get_thread_area) (lwpid_of (thread), &thread_area) == -1)
1661 return fast_tracepoint_collecting (thread_area, lwp->stop_pc, status);
1664 /* The reason we resume in the caller, is because we want to be able
1665 to pass lwp->status_pending as WSTAT, and we need to clear
1666 status_pending_p before resuming, otherwise, linux_resume_one_lwp
1667 refuses to resume. */
1670 maybe_move_out_of_jump_pad (struct lwp_info *lwp, int *wstat)
1672 struct thread_info *saved_thread;
1674 saved_thread = current_thread;
1675 current_thread = get_lwp_thread (lwp);
1678 || (WIFSTOPPED (*wstat) && WSTOPSIG (*wstat) != SIGTRAP))
1679 && supports_fast_tracepoints ()
1680 && agent_loaded_p ())
1682 struct fast_tpoint_collect_status status;
1686 debug_printf ("Checking whether LWP %ld needs to move out of the "
1688 lwpid_of (current_thread));
1690 r = linux_fast_tracepoint_collecting (lwp, &status);
1693 || (WSTOPSIG (*wstat) != SIGILL
1694 && WSTOPSIG (*wstat) != SIGFPE
1695 && WSTOPSIG (*wstat) != SIGSEGV
1696 && WSTOPSIG (*wstat) != SIGBUS))
1698 lwp->collecting_fast_tracepoint = r;
1702 if (r == 1 && lwp->exit_jump_pad_bkpt == NULL)
1704 /* Haven't executed the original instruction yet.
1705 Set breakpoint there, and wait till it's hit,
1706 then single-step until exiting the jump pad. */
1707 lwp->exit_jump_pad_bkpt
1708 = set_breakpoint_at (status.adjusted_insn_addr, NULL);
1712 debug_printf ("Checking whether LWP %ld needs to move out of "
1713 "the jump pad...it does\n",
1714 lwpid_of (current_thread));
1715 current_thread = saved_thread;
1722 /* If we get a synchronous signal while collecting, *and*
1723 while executing the (relocated) original instruction,
1724 reset the PC to point at the tpoint address, before
1725 reporting to GDB. Otherwise, it's an IPA lib bug: just
1726 report the signal to GDB, and pray for the best. */
1728 lwp->collecting_fast_tracepoint = 0;
1731 && (status.adjusted_insn_addr <= lwp->stop_pc
1732 && lwp->stop_pc < status.adjusted_insn_addr_end))
1735 struct regcache *regcache;
1737 /* The si_addr on a few signals references the address
1738 of the faulting instruction. Adjust that as
1740 if ((WSTOPSIG (*wstat) == SIGILL
1741 || WSTOPSIG (*wstat) == SIGFPE
1742 || WSTOPSIG (*wstat) == SIGBUS
1743 || WSTOPSIG (*wstat) == SIGSEGV)
1744 && ptrace (PTRACE_GETSIGINFO, lwpid_of (current_thread),
1745 (PTRACE_TYPE_ARG3) 0, &info) == 0
1746 /* Final check just to make sure we don't clobber
1747 the siginfo of non-kernel-sent signals. */
1748 && (uintptr_t) info.si_addr == lwp->stop_pc)
1750 info.si_addr = (void *) (uintptr_t) status.tpoint_addr;
1751 ptrace (PTRACE_SETSIGINFO, lwpid_of (current_thread),
1752 (PTRACE_TYPE_ARG3) 0, &info);
1755 regcache = get_thread_regcache (current_thread, 1);
1756 (*the_low_target.set_pc) (regcache, status.tpoint_addr);
1757 lwp->stop_pc = status.tpoint_addr;
1759 /* Cancel any fast tracepoint lock this thread was
1761 force_unlock_trace_buffer ();
1764 if (lwp->exit_jump_pad_bkpt != NULL)
1767 debug_printf ("Cancelling fast exit-jump-pad: removing bkpt. "
1768 "stopping all threads momentarily.\n");
1770 stop_all_lwps (1, lwp);
1772 delete_breakpoint (lwp->exit_jump_pad_bkpt);
1773 lwp->exit_jump_pad_bkpt = NULL;
1775 unstop_all_lwps (1, lwp);
1777 gdb_assert (lwp->suspended >= 0);
1783 debug_printf ("Checking whether LWP %ld needs to move out of the "
1785 lwpid_of (current_thread));
1787 current_thread = saved_thread;
1791 /* Enqueue one signal in the "signals to report later when out of the
1795 enqueue_one_deferred_signal (struct lwp_info *lwp, int *wstat)
1797 struct pending_signals *p_sig;
1798 struct thread_info *thread = get_lwp_thread (lwp);
1801 debug_printf ("Deferring signal %d for LWP %ld.\n",
1802 WSTOPSIG (*wstat), lwpid_of (thread));
1806 struct pending_signals *sig;
1808 for (sig = lwp->pending_signals_to_report;
1811 debug_printf (" Already queued %d\n",
1814 debug_printf (" (no more currently queued signals)\n");
1817 /* Don't enqueue non-RT signals if they are already in the deferred
1818 queue. (SIGSTOP being the easiest signal to see ending up here
1820 if (WSTOPSIG (*wstat) < __SIGRTMIN)
1822 struct pending_signals *sig;
1824 for (sig = lwp->pending_signals_to_report;
1828 if (sig->signal == WSTOPSIG (*wstat))
1831 debug_printf ("Not requeuing already queued non-RT signal %d"
1840 p_sig = xmalloc (sizeof (*p_sig));
1841 p_sig->prev = lwp->pending_signals_to_report;
1842 p_sig->signal = WSTOPSIG (*wstat);
1843 memset (&p_sig->info, 0, sizeof (siginfo_t));
1844 ptrace (PTRACE_GETSIGINFO, lwpid_of (thread), (PTRACE_TYPE_ARG3) 0,
1847 lwp->pending_signals_to_report = p_sig;
1850 /* Dequeue one signal from the "signals to report later when out of
1851 the jump pad" list. */
1854 dequeue_one_deferred_signal (struct lwp_info *lwp, int *wstat)
1856 struct thread_info *thread = get_lwp_thread (lwp);
1858 if (lwp->pending_signals_to_report != NULL)
1860 struct pending_signals **p_sig;
1862 p_sig = &lwp->pending_signals_to_report;
1863 while ((*p_sig)->prev != NULL)
1864 p_sig = &(*p_sig)->prev;
1866 *wstat = W_STOPCODE ((*p_sig)->signal);
1867 if ((*p_sig)->info.si_signo != 0)
1868 ptrace (PTRACE_SETSIGINFO, lwpid_of (thread), (PTRACE_TYPE_ARG3) 0,
1874 debug_printf ("Reporting deferred signal %d for LWP %ld.\n",
1875 WSTOPSIG (*wstat), lwpid_of (thread));
1879 struct pending_signals *sig;
1881 for (sig = lwp->pending_signals_to_report;
1884 debug_printf (" Still queued %d\n",
1887 debug_printf (" (no more queued signals)\n");
1896 /* Fetch the possibly triggered data watchpoint info and store it in
1899 On some archs, like x86, that use debug registers to set
1900 watchpoints, it's possible that the way to know which watched
1901 address trapped, is to check the register that is used to select
1902 which address to watch. Problem is, between setting the watchpoint
1903 and reading back which data address trapped, the user may change
1904 the set of watchpoints, and, as a consequence, GDB changes the
1905 debug registers in the inferior. To avoid reading back a stale
1906 stopped-data-address when that happens, we cache in LP the fact
1907 that a watchpoint trapped, and the corresponding data address, as
1908 soon as we see CHILD stop with a SIGTRAP. If GDB changes the debug
1909 registers meanwhile, we have the cached data we can rely on. */
1912 check_stopped_by_watchpoint (struct lwp_info *child)
1914 if (the_low_target.stopped_by_watchpoint != NULL)
1916 struct thread_info *saved_thread;
1918 saved_thread = current_thread;
1919 current_thread = get_lwp_thread (child);
1921 if (the_low_target.stopped_by_watchpoint ())
1923 child->stop_reason = TARGET_STOPPED_BY_WATCHPOINT;
1925 if (the_low_target.stopped_data_address != NULL)
1926 child->stopped_data_address
1927 = the_low_target.stopped_data_address ();
1929 child->stopped_data_address = 0;
1932 current_thread = saved_thread;
1935 return child->stop_reason == TARGET_STOPPED_BY_WATCHPOINT;
1938 /* Do low-level handling of the event, and check if we should go on
1939 and pass it to caller code. Return the affected lwp if we are, or
1942 static struct lwp_info *
1943 linux_low_filter_event (int lwpid, int wstat)
1945 struct lwp_info *child;
1946 struct thread_info *thread;
1947 int have_stop_pc = 0;
1949 child = find_lwp_pid (pid_to_ptid (lwpid));
1951 /* If we didn't find a process, one of two things presumably happened:
1952 - A process we started and then detached from has exited. Ignore it.
1953 - A process we are controlling has forked and the new child's stop
1954 was reported to us by the kernel. Save its PID. */
1955 if (child == NULL && WIFSTOPPED (wstat))
1957 add_to_pid_list (&stopped_pids, lwpid, wstat);
1960 else if (child == NULL)
1963 thread = get_lwp_thread (child);
1967 child->last_status = wstat;
1969 /* Check if the thread has exited. */
1970 if ((WIFEXITED (wstat) || WIFSIGNALED (wstat)))
1973 debug_printf ("LLFE: %d exited.\n", lwpid);
1974 if (num_lwps (pid_of (thread)) > 1)
1977 /* If there is at least one more LWP, then the exit signal was
1978 not the end of the debugged application and should be
1985 /* This was the last lwp in the process. Since events are
1986 serialized to GDB core, and we can't report this one
1987 right now, but GDB core and the other target layers will
1988 want to be notified about the exit code/signal, leave the
1989 status pending for the next time we're able to report
1991 mark_lwp_dead (child, wstat);
1996 gdb_assert (WIFSTOPPED (wstat));
1998 if (WIFSTOPPED (wstat))
2000 struct process_info *proc;
2002 /* Architecture-specific setup after inferior is running. This
2003 needs to happen after we have attached to the inferior and it
2004 is stopped for the first time, but before we access any
2005 inferior registers. */
2006 proc = find_process_pid (pid_of (thread));
2007 if (proc->priv->new_inferior)
2009 struct thread_info *saved_thread;
2011 saved_thread = current_thread;
2012 current_thread = thread;
2014 the_low_target.arch_setup ();
2016 current_thread = saved_thread;
2018 proc->priv->new_inferior = 0;
2022 if (WIFSTOPPED (wstat) && child->must_set_ptrace_flags)
2024 struct process_info *proc = find_process_pid (pid_of (thread));
2026 linux_enable_event_reporting (lwpid, proc->attached);
2027 child->must_set_ptrace_flags = 0;
2030 /* Be careful to not overwrite stop_pc until
2031 check_stopped_by_breakpoint is called. */
2032 if (WIFSTOPPED (wstat) && WSTOPSIG (wstat) == SIGTRAP
2033 && linux_is_extended_waitstatus (wstat))
2035 child->stop_pc = get_pc (child);
2036 handle_extended_wait (child, wstat);
2040 /* Check first whether this was a SW/HW breakpoint before checking
2041 watchpoints, because at least s390 can't tell the data address of
2042 hardware watchpoint hits, and returns stopped-by-watchpoint as
2043 long as there's a watchpoint set. */
2044 if (WIFSTOPPED (wstat) && linux_wstatus_maybe_breakpoint (wstat))
2046 if (check_stopped_by_breakpoint (child))
2050 /* Note that TRAP_HWBKPT can indicate either a hardware breakpoint
2051 or hardware watchpoint. Check which is which if we got
2052 TARGET_STOPPED_BY_HW_BREAKPOINT. */
2053 if (WIFSTOPPED (wstat) && WSTOPSIG (wstat) == SIGTRAP
2054 && (child->stop_reason == TARGET_STOPPED_BY_NO_REASON
2055 || child->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT))
2056 check_stopped_by_watchpoint (child);
2059 child->stop_pc = get_pc (child);
2061 if (WIFSTOPPED (wstat) && WSTOPSIG (wstat) == SIGSTOP
2062 && child->stop_expected)
2065 debug_printf ("Expected stop.\n");
2066 child->stop_expected = 0;
2068 if (thread->last_resume_kind == resume_stop)
2070 /* We want to report the stop to the core. Treat the
2071 SIGSTOP as a normal event. */
2073 debug_printf ("LLW: resume_stop SIGSTOP caught for %s.\n",
2074 target_pid_to_str (ptid_of (thread)));
2076 else if (stopping_threads != NOT_STOPPING_THREADS)
2078 /* Stopping threads. We don't want this SIGSTOP to end up
2081 debug_printf ("LLW: SIGSTOP caught for %s "
2082 "while stopping threads.\n",
2083 target_pid_to_str (ptid_of (thread)));
2088 /* This is a delayed SIGSTOP. Filter out the event. */
2090 debug_printf ("LLW: %s %s, 0, 0 (discard delayed SIGSTOP)\n",
2091 child->stepping ? "step" : "continue",
2092 target_pid_to_str (ptid_of (thread)));
2094 linux_resume_one_lwp (child, child->stepping, 0, NULL);
2099 child->status_pending_p = 1;
2100 child->status_pending = wstat;
2104 /* Resume LWPs that are currently stopped without any pending status
2105 to report, but are resumed from the core's perspective. */
2108 resume_stopped_resumed_lwps (struct inferior_list_entry *entry)
2110 struct thread_info *thread = (struct thread_info *) entry;
2111 struct lwp_info *lp = get_thread_lwp (thread);
2114 && !lp->status_pending_p
2115 && thread->last_resume_kind != resume_stop
2116 && thread->last_status.kind == TARGET_WAITKIND_IGNORE)
2118 int step = thread->last_resume_kind == resume_step;
2121 debug_printf ("RSRL: resuming stopped-resumed LWP %s at %s: step=%d\n",
2122 target_pid_to_str (ptid_of (thread)),
2123 paddress (lp->stop_pc),
2126 linux_resume_one_lwp (lp, step, GDB_SIGNAL_0, NULL);
2130 /* Wait for an event from child(ren) WAIT_PTID, and return any that
2131 match FILTER_PTID (leaving others pending). The PTIDs can be:
2132 minus_one_ptid, to specify any child; a pid PTID, specifying all
2133 lwps of a thread group; or a PTID representing a single lwp. Store
2134 the stop status through the status pointer WSTAT. OPTIONS is
2135 passed to the waitpid call. Return 0 if no event was found and
2136 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
2137 was found. Return the PID of the stopped child otherwise. */
2140 linux_wait_for_event_filtered (ptid_t wait_ptid, ptid_t filter_ptid,
2141 int *wstatp, int options)
2143 struct thread_info *event_thread;
2144 struct lwp_info *event_child, *requested_child;
2145 sigset_t block_mask, prev_mask;
2148 /* N.B. event_thread points to the thread_info struct that contains
2149 event_child. Keep them in sync. */
2150 event_thread = NULL;
2152 requested_child = NULL;
2154 /* Check for a lwp with a pending status. */
2156 if (ptid_equal (filter_ptid, minus_one_ptid) || ptid_is_pid (filter_ptid))
2158 event_thread = (struct thread_info *)
2159 find_inferior (&all_threads, status_pending_p_callback, &filter_ptid);
2160 if (event_thread != NULL)
2161 event_child = get_thread_lwp (event_thread);
2162 if (debug_threads && event_thread)
2163 debug_printf ("Got a pending child %ld\n", lwpid_of (event_thread));
2165 else if (!ptid_equal (filter_ptid, null_ptid))
2167 requested_child = find_lwp_pid (filter_ptid);
2169 if (stopping_threads == NOT_STOPPING_THREADS
2170 && requested_child->status_pending_p
2171 && requested_child->collecting_fast_tracepoint)
2173 enqueue_one_deferred_signal (requested_child,
2174 &requested_child->status_pending);
2175 requested_child->status_pending_p = 0;
2176 requested_child->status_pending = 0;
2177 linux_resume_one_lwp (requested_child, 0, 0, NULL);
2180 if (requested_child->suspended
2181 && requested_child->status_pending_p)
2183 internal_error (__FILE__, __LINE__,
2184 "requesting an event out of a"
2185 " suspended child?");
2188 if (requested_child->status_pending_p)
2190 event_child = requested_child;
2191 event_thread = get_lwp_thread (event_child);
2195 if (event_child != NULL)
2198 debug_printf ("Got an event from pending child %ld (%04x)\n",
2199 lwpid_of (event_thread), event_child->status_pending);
2200 *wstatp = event_child->status_pending;
2201 event_child->status_pending_p = 0;
2202 event_child->status_pending = 0;
2203 current_thread = event_thread;
2204 return lwpid_of (event_thread);
2207 /* But if we don't find a pending event, we'll have to wait.
2209 We only enter this loop if no process has a pending wait status.
2210 Thus any action taken in response to a wait status inside this
2211 loop is responding as soon as we detect the status, not after any
2214 /* Make sure SIGCHLD is blocked until the sigsuspend below. Block
2215 all signals while here. */
2216 sigfillset (&block_mask);
2217 sigprocmask (SIG_BLOCK, &block_mask, &prev_mask);
2219 /* Always pull all events out of the kernel. We'll randomly select
2220 an event LWP out of all that have events, to prevent
2222 while (event_child == NULL)
2226 /* Always use -1 and WNOHANG, due to couple of a kernel/ptrace
2229 - If the thread group leader exits while other threads in the
2230 thread group still exist, waitpid(TGID, ...) hangs. That
2231 waitpid won't return an exit status until the other threads
2232 in the group are reaped.
2234 - When a non-leader thread execs, that thread just vanishes
2235 without reporting an exit (so we'd hang if we waited for it
2236 explicitly in that case). The exec event is reported to
2237 the TGID pid (although we don't currently enable exec
2240 ret = my_waitpid (-1, wstatp, options | WNOHANG);
2243 debug_printf ("LWFE: waitpid(-1, ...) returned %d, %s\n",
2244 ret, errno ? strerror (errno) : "ERRNO-OK");
2250 debug_printf ("LLW: waitpid %ld received %s\n",
2251 (long) ret, status_to_str (*wstatp));
2254 /* Filter all events. IOW, leave all events pending. We'll
2255 randomly select an event LWP out of all that have events
2257 linux_low_filter_event (ret, *wstatp);
2258 /* Retry until nothing comes out of waitpid. A single
2259 SIGCHLD can indicate more than one child stopped. */
2263 /* Now that we've pulled all events out of the kernel, resume
2264 LWPs that don't have an interesting event to report. */
2265 if (stopping_threads == NOT_STOPPING_THREADS)
2266 for_each_inferior (&all_threads, resume_stopped_resumed_lwps);
2268 /* ... and find an LWP with a status to report to the core, if
2270 event_thread = (struct thread_info *)
2271 find_inferior (&all_threads, status_pending_p_callback, &filter_ptid);
2272 if (event_thread != NULL)
2274 event_child = get_thread_lwp (event_thread);
2275 *wstatp = event_child->status_pending;
2276 event_child->status_pending_p = 0;
2277 event_child->status_pending = 0;
2281 /* Check for zombie thread group leaders. Those can't be reaped
2282 until all other threads in the thread group are. */
2283 check_zombie_leaders ();
2285 /* If there are no resumed children left in the set of LWPs we
2286 want to wait for, bail. We can't just block in
2287 waitpid/sigsuspend, because lwps might have been left stopped
2288 in trace-stop state, and we'd be stuck forever waiting for
2289 their status to change (which would only happen if we resumed
2290 them). Even if WNOHANG is set, this return code is preferred
2291 over 0 (below), as it is more detailed. */
2292 if ((find_inferior (&all_threads,
2293 not_stopped_callback,
2294 &wait_ptid) == NULL))
2297 debug_printf ("LLW: exit (no unwaited-for LWP)\n");
2298 sigprocmask (SIG_SETMASK, &prev_mask, NULL);
2302 /* No interesting event to report to the caller. */
2303 if ((options & WNOHANG))
2306 debug_printf ("WNOHANG set, no event found\n");
2308 sigprocmask (SIG_SETMASK, &prev_mask, NULL);
2312 /* Block until we get an event reported with SIGCHLD. */
2314 debug_printf ("sigsuspend'ing\n");
2316 sigsuspend (&prev_mask);
2317 sigprocmask (SIG_SETMASK, &prev_mask, NULL);
2321 sigprocmask (SIG_SETMASK, &prev_mask, NULL);
2323 current_thread = event_thread;
2325 /* Check for thread exit. */
2326 if (! WIFSTOPPED (*wstatp))
2328 gdb_assert (last_thread_of_process_p (pid_of (event_thread)));
2331 debug_printf ("LWP %d is the last lwp of process. "
2332 "Process %ld exiting.\n",
2333 pid_of (event_thread), lwpid_of (event_thread));
2334 return lwpid_of (event_thread);
2337 return lwpid_of (event_thread);
2340 /* Wait for an event from child(ren) PTID. PTIDs can be:
2341 minus_one_ptid, to specify any child; a pid PTID, specifying all
2342 lwps of a thread group; or a PTID representing a single lwp. Store
2343 the stop status through the status pointer WSTAT. OPTIONS is
2344 passed to the waitpid call. Return 0 if no event was found and
2345 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
2346 was found. Return the PID of the stopped child otherwise. */
2349 linux_wait_for_event (ptid_t ptid, int *wstatp, int options)
2351 return linux_wait_for_event_filtered (ptid, ptid, wstatp, options);
2354 /* Count the LWP's that have had events. */
2357 count_events_callback (struct inferior_list_entry *entry, void *data)
2359 struct thread_info *thread = (struct thread_info *) entry;
2360 struct lwp_info *lp = get_thread_lwp (thread);
2363 gdb_assert (count != NULL);
2365 /* Count only resumed LWPs that have an event pending. */
2366 if (thread->last_status.kind == TARGET_WAITKIND_IGNORE
2367 && lp->status_pending_p)
2373 /* Select the LWP (if any) that is currently being single-stepped. */
2376 select_singlestep_lwp_callback (struct inferior_list_entry *entry, void *data)
2378 struct thread_info *thread = (struct thread_info *) entry;
2379 struct lwp_info *lp = get_thread_lwp (thread);
2381 if (thread->last_status.kind == TARGET_WAITKIND_IGNORE
2382 && thread->last_resume_kind == resume_step
2383 && lp->status_pending_p)
2389 /* Select the Nth LWP that has had an event. */
2392 select_event_lwp_callback (struct inferior_list_entry *entry, void *data)
2394 struct thread_info *thread = (struct thread_info *) entry;
2395 struct lwp_info *lp = get_thread_lwp (thread);
2396 int *selector = data;
2398 gdb_assert (selector != NULL);
2400 /* Select only resumed LWPs that have an event pending. */
2401 if (thread->last_status.kind == TARGET_WAITKIND_IGNORE
2402 && lp->status_pending_p)
2403 if ((*selector)-- == 0)
2409 /* Select one LWP out of those that have events pending. */
2412 select_event_lwp (struct lwp_info **orig_lp)
2415 int random_selector;
2416 struct thread_info *event_thread = NULL;
2418 /* In all-stop, give preference to the LWP that is being
2419 single-stepped. There will be at most one, and it's the LWP that
2420 the core is most interested in. If we didn't do this, then we'd
2421 have to handle pending step SIGTRAPs somehow in case the core
2422 later continues the previously-stepped thread, otherwise we'd
2423 report the pending SIGTRAP, and the core, not having stepped the
2424 thread, wouldn't understand what the trap was for, and therefore
2425 would report it to the user as a random signal. */
2429 = (struct thread_info *) find_inferior (&all_threads,
2430 select_singlestep_lwp_callback,
2432 if (event_thread != NULL)
2435 debug_printf ("SEL: Select single-step %s\n",
2436 target_pid_to_str (ptid_of (event_thread)));
2439 if (event_thread == NULL)
2441 /* No single-stepping LWP. Select one at random, out of those
2442 which have had events. */
2444 /* First see how many events we have. */
2445 find_inferior (&all_threads, count_events_callback, &num_events);
2446 gdb_assert (num_events > 0);
2448 /* Now randomly pick a LWP out of those that have had
2450 random_selector = (int)
2451 ((num_events * (double) rand ()) / (RAND_MAX + 1.0));
2453 if (debug_threads && num_events > 1)
2454 debug_printf ("SEL: Found %d SIGTRAP events, selecting #%d\n",
2455 num_events, random_selector);
2458 = (struct thread_info *) find_inferior (&all_threads,
2459 select_event_lwp_callback,
2463 if (event_thread != NULL)
2465 struct lwp_info *event_lp = get_thread_lwp (event_thread);
2467 /* Switch the event LWP. */
2468 *orig_lp = event_lp;
2472 /* Decrement the suspend count of an LWP. */
2475 unsuspend_one_lwp (struct inferior_list_entry *entry, void *except)
2477 struct thread_info *thread = (struct thread_info *) entry;
2478 struct lwp_info *lwp = get_thread_lwp (thread);
2480 /* Ignore EXCEPT. */
2486 gdb_assert (lwp->suspended >= 0);
2490 /* Decrement the suspend count of all LWPs, except EXCEPT, if non
2494 unsuspend_all_lwps (struct lwp_info *except)
2496 find_inferior (&all_threads, unsuspend_one_lwp, except);
2499 static void move_out_of_jump_pad_callback (struct inferior_list_entry *entry);
2500 static int stuck_in_jump_pad_callback (struct inferior_list_entry *entry,
2502 static int lwp_running (struct inferior_list_entry *entry, void *data);
2503 static ptid_t linux_wait_1 (ptid_t ptid,
2504 struct target_waitstatus *ourstatus,
2505 int target_options);
2507 /* Stabilize threads (move out of jump pads).
2509 If a thread is midway collecting a fast tracepoint, we need to
2510 finish the collection and move it out of the jump pad before
2511 reporting the signal.
2513 This avoids recursion while collecting (when a signal arrives
2514 midway, and the signal handler itself collects), which would trash
2515 the trace buffer. In case the user set a breakpoint in a signal
2516 handler, this avoids the backtrace showing the jump pad, etc..
2517 Most importantly, there are certain things we can't do safely if
2518 threads are stopped in a jump pad (or in its callee's). For
2521 - starting a new trace run. A thread still collecting the
2522 previous run, could trash the trace buffer when resumed. The trace
2523 buffer control structures would have been reset but the thread had
2524 no way to tell. The thread could even midway memcpy'ing to the
2525 buffer, which would mean that when resumed, it would clobber the
2526 trace buffer that had been set for a new run.
2528 - we can't rewrite/reuse the jump pads for new tracepoints
2529 safely. Say you do tstart while a thread is stopped midway while
2530 collecting. When the thread is later resumed, it finishes the
2531 collection, and returns to the jump pad, to execute the original
2532 instruction that was under the tracepoint jump at the time the
2533 older run had been started. If the jump pad had been rewritten
2534 since for something else in the new run, the thread would now
2535 execute the wrong / random instructions. */
2538 linux_stabilize_threads (void)
2540 struct thread_info *saved_thread;
2541 struct thread_info *thread_stuck;
2544 = (struct thread_info *) find_inferior (&all_threads,
2545 stuck_in_jump_pad_callback,
2547 if (thread_stuck != NULL)
2550 debug_printf ("can't stabilize, LWP %ld is stuck in jump pad\n",
2551 lwpid_of (thread_stuck));
2555 saved_thread = current_thread;
2557 stabilizing_threads = 1;
2560 for_each_inferior (&all_threads, move_out_of_jump_pad_callback);
2562 /* Loop until all are stopped out of the jump pads. */
2563 while (find_inferior (&all_threads, lwp_running, NULL) != NULL)
2565 struct target_waitstatus ourstatus;
2566 struct lwp_info *lwp;
2569 /* Note that we go through the full wait even loop. While
2570 moving threads out of jump pad, we need to be able to step
2571 over internal breakpoints and such. */
2572 linux_wait_1 (minus_one_ptid, &ourstatus, 0);
2574 if (ourstatus.kind == TARGET_WAITKIND_STOPPED)
2576 lwp = get_thread_lwp (current_thread);
2581 if (ourstatus.value.sig != GDB_SIGNAL_0
2582 || current_thread->last_resume_kind == resume_stop)
2584 wstat = W_STOPCODE (gdb_signal_to_host (ourstatus.value.sig));
2585 enqueue_one_deferred_signal (lwp, &wstat);
2590 find_inferior (&all_threads, unsuspend_one_lwp, NULL);
2592 stabilizing_threads = 0;
2594 current_thread = saved_thread;
2599 = (struct thread_info *) find_inferior (&all_threads,
2600 stuck_in_jump_pad_callback,
2602 if (thread_stuck != NULL)
2603 debug_printf ("couldn't stabilize, LWP %ld got stuck in jump pad\n",
2604 lwpid_of (thread_stuck));
2608 static void async_file_mark (void);
2610 /* Convenience function that is called when the kernel reports an
2611 event that is not passed out to GDB. */
2614 ignore_event (struct target_waitstatus *ourstatus)
2616 /* If we got an event, there may still be others, as a single
2617 SIGCHLD can indicate more than one child stopped. This forces
2618 another target_wait call. */
2621 ourstatus->kind = TARGET_WAITKIND_IGNORE;
2625 /* Wait for process, returns status. */
2628 linux_wait_1 (ptid_t ptid,
2629 struct target_waitstatus *ourstatus, int target_options)
2632 struct lwp_info *event_child;
2635 int step_over_finished;
2636 int bp_explains_trap;
2637 int maybe_internal_trap;
2645 debug_printf ("linux_wait_1: [%s]\n", target_pid_to_str (ptid));
2648 /* Translate generic target options into linux options. */
2650 if (target_options & TARGET_WNOHANG)
2653 bp_explains_trap = 0;
2656 ourstatus->kind = TARGET_WAITKIND_IGNORE;
2658 if (ptid_equal (step_over_bkpt, null_ptid))
2659 pid = linux_wait_for_event (ptid, &w, options);
2663 debug_printf ("step_over_bkpt set [%s], doing a blocking wait\n",
2664 target_pid_to_str (step_over_bkpt));
2665 pid = linux_wait_for_event (step_over_bkpt, &w, options & ~WNOHANG);
2670 gdb_assert (target_options & TARGET_WNOHANG);
2674 debug_printf ("linux_wait_1 ret = null_ptid, "
2675 "TARGET_WAITKIND_IGNORE\n");
2679 ourstatus->kind = TARGET_WAITKIND_IGNORE;
2686 debug_printf ("linux_wait_1 ret = null_ptid, "
2687 "TARGET_WAITKIND_NO_RESUMED\n");
2691 ourstatus->kind = TARGET_WAITKIND_NO_RESUMED;
2695 event_child = get_thread_lwp (current_thread);
2697 /* linux_wait_for_event only returns an exit status for the last
2698 child of a process. Report it. */
2699 if (WIFEXITED (w) || WIFSIGNALED (w))
2703 ourstatus->kind = TARGET_WAITKIND_EXITED;
2704 ourstatus->value.integer = WEXITSTATUS (w);
2708 debug_printf ("linux_wait_1 ret = %s, exited with "
2710 target_pid_to_str (ptid_of (current_thread)),
2717 ourstatus->kind = TARGET_WAITKIND_SIGNALLED;
2718 ourstatus->value.sig = gdb_signal_from_host (WTERMSIG (w));
2722 debug_printf ("linux_wait_1 ret = %s, terminated with "
2724 target_pid_to_str (ptid_of (current_thread)),
2730 return ptid_of (current_thread);
2733 /* If step-over executes a breakpoint instruction, it means a
2734 gdb/gdbserver breakpoint had been planted on top of a permanent
2735 breakpoint. The PC has been adjusted by
2736 check_stopped_by_breakpoint to point at the breakpoint address.
2737 Advance the PC manually past the breakpoint, otherwise the
2738 program would keep trapping the permanent breakpoint forever. */
2739 if (!ptid_equal (step_over_bkpt, null_ptid)
2740 && event_child->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT)
2742 unsigned int increment_pc = the_low_target.breakpoint_len;
2746 debug_printf ("step-over for %s executed software breakpoint\n",
2747 target_pid_to_str (ptid_of (current_thread)));
2750 if (increment_pc != 0)
2752 struct regcache *regcache
2753 = get_thread_regcache (current_thread, 1);
2755 event_child->stop_pc += increment_pc;
2756 (*the_low_target.set_pc) (regcache, event_child->stop_pc);
2758 if (!(*the_low_target.breakpoint_at) (event_child->stop_pc))
2759 event_child->stop_reason = TARGET_STOPPED_BY_NO_REASON;
2763 /* If this event was not handled before, and is not a SIGTRAP, we
2764 report it. SIGILL and SIGSEGV are also treated as traps in case
2765 a breakpoint is inserted at the current PC. If this target does
2766 not support internal breakpoints at all, we also report the
2767 SIGTRAP without further processing; it's of no concern to us. */
2769 = (supports_breakpoints ()
2770 && (WSTOPSIG (w) == SIGTRAP
2771 || ((WSTOPSIG (w) == SIGILL
2772 || WSTOPSIG (w) == SIGSEGV)
2773 && (*the_low_target.breakpoint_at) (event_child->stop_pc))));
2775 if (maybe_internal_trap)
2777 /* Handle anything that requires bookkeeping before deciding to
2778 report the event or continue waiting. */
2780 /* First check if we can explain the SIGTRAP with an internal
2781 breakpoint, or if we should possibly report the event to GDB.
2782 Do this before anything that may remove or insert a
2784 bp_explains_trap = breakpoint_inserted_here (event_child->stop_pc);
2786 /* We have a SIGTRAP, possibly a step-over dance has just
2787 finished. If so, tweak the state machine accordingly,
2788 reinsert breakpoints and delete any reinsert (software
2789 single-step) breakpoints. */
2790 step_over_finished = finish_step_over (event_child);
2792 /* Now invoke the callbacks of any internal breakpoints there. */
2793 check_breakpoints (event_child->stop_pc);
2795 /* Handle tracepoint data collecting. This may overflow the
2796 trace buffer, and cause a tracing stop, removing
2798 trace_event = handle_tracepoints (event_child);
2800 if (bp_explains_trap)
2802 /* If we stepped or ran into an internal breakpoint, we've
2803 already handled it. So next time we resume (from this
2804 PC), we should step over it. */
2806 debug_printf ("Hit a gdbserver breakpoint.\n");
2808 if (breakpoint_here (event_child->stop_pc))
2809 event_child->need_step_over = 1;
2814 /* We have some other signal, possibly a step-over dance was in
2815 progress, and it should be cancelled too. */
2816 step_over_finished = finish_step_over (event_child);
2819 /* We have all the data we need. Either report the event to GDB, or
2820 resume threads and keep waiting for more. */
2822 /* If we're collecting a fast tracepoint, finish the collection and
2823 move out of the jump pad before delivering a signal. See
2824 linux_stabilize_threads. */
2827 && WSTOPSIG (w) != SIGTRAP
2828 && supports_fast_tracepoints ()
2829 && agent_loaded_p ())
2832 debug_printf ("Got signal %d for LWP %ld. Check if we need "
2833 "to defer or adjust it.\n",
2834 WSTOPSIG (w), lwpid_of (current_thread));
2836 /* Allow debugging the jump pad itself. */
2837 if (current_thread->last_resume_kind != resume_step
2838 && maybe_move_out_of_jump_pad (event_child, &w))
2840 enqueue_one_deferred_signal (event_child, &w);
2843 debug_printf ("Signal %d for LWP %ld deferred (in jump pad)\n",
2844 WSTOPSIG (w), lwpid_of (current_thread));
2846 linux_resume_one_lwp (event_child, 0, 0, NULL);
2848 return ignore_event (ourstatus);
2852 if (event_child->collecting_fast_tracepoint)
2855 debug_printf ("LWP %ld was trying to move out of the jump pad (%d). "
2856 "Check if we're already there.\n",
2857 lwpid_of (current_thread),
2858 event_child->collecting_fast_tracepoint);
2862 event_child->collecting_fast_tracepoint
2863 = linux_fast_tracepoint_collecting (event_child, NULL);
2865 if (event_child->collecting_fast_tracepoint != 1)
2867 /* No longer need this breakpoint. */
2868 if (event_child->exit_jump_pad_bkpt != NULL)
2871 debug_printf ("No longer need exit-jump-pad bkpt; removing it."
2872 "stopping all threads momentarily.\n");
2874 /* Other running threads could hit this breakpoint.
2875 We don't handle moribund locations like GDB does,
2876 instead we always pause all threads when removing
2877 breakpoints, so that any step-over or
2878 decr_pc_after_break adjustment is always taken
2879 care of while the breakpoint is still
2881 stop_all_lwps (1, event_child);
2883 delete_breakpoint (event_child->exit_jump_pad_bkpt);
2884 event_child->exit_jump_pad_bkpt = NULL;
2886 unstop_all_lwps (1, event_child);
2888 gdb_assert (event_child->suspended >= 0);
2892 if (event_child->collecting_fast_tracepoint == 0)
2895 debug_printf ("fast tracepoint finished "
2896 "collecting successfully.\n");
2898 /* We may have a deferred signal to report. */
2899 if (dequeue_one_deferred_signal (event_child, &w))
2902 debug_printf ("dequeued one signal.\n");
2907 debug_printf ("no deferred signals.\n");
2909 if (stabilizing_threads)
2911 ourstatus->kind = TARGET_WAITKIND_STOPPED;
2912 ourstatus->value.sig = GDB_SIGNAL_0;
2916 debug_printf ("linux_wait_1 ret = %s, stopped "
2917 "while stabilizing threads\n",
2918 target_pid_to_str (ptid_of (current_thread)));
2922 return ptid_of (current_thread);
2928 /* Check whether GDB would be interested in this event. */
2930 /* If GDB is not interested in this signal, don't stop other
2931 threads, and don't report it to GDB. Just resume the inferior
2932 right away. We do this for threading-related signals as well as
2933 any that GDB specifically requested we ignore. But never ignore
2934 SIGSTOP if we sent it ourselves, and do not ignore signals when
2935 stepping - they may require special handling to skip the signal
2936 handler. Also never ignore signals that could be caused by a
2938 /* FIXME drow/2002-06-09: Get signal numbers from the inferior's
2941 && current_thread->last_resume_kind != resume_step
2943 #if defined (USE_THREAD_DB) && !defined (__ANDROID__)
2944 (current_process ()->priv->thread_db != NULL
2945 && (WSTOPSIG (w) == __SIGRTMIN
2946 || WSTOPSIG (w) == __SIGRTMIN + 1))
2949 (pass_signals[gdb_signal_from_host (WSTOPSIG (w))]
2950 && !(WSTOPSIG (w) == SIGSTOP
2951 && current_thread->last_resume_kind == resume_stop)
2952 && !linux_wstatus_maybe_breakpoint (w))))
2954 siginfo_t info, *info_p;
2957 debug_printf ("Ignored signal %d for LWP %ld.\n",
2958 WSTOPSIG (w), lwpid_of (current_thread));
2960 if (ptrace (PTRACE_GETSIGINFO, lwpid_of (current_thread),
2961 (PTRACE_TYPE_ARG3) 0, &info) == 0)
2965 linux_resume_one_lwp (event_child, event_child->stepping,
2966 WSTOPSIG (w), info_p);
2967 return ignore_event (ourstatus);
2970 /* Note that all addresses are always "out of the step range" when
2971 there's no range to begin with. */
2972 in_step_range = lwp_in_step_range (event_child);
2974 /* If GDB wanted this thread to single step, and the thread is out
2975 of the step range, we always want to report the SIGTRAP, and let
2976 GDB handle it. Watchpoints should always be reported. So should
2977 signals we can't explain. A SIGTRAP we can't explain could be a
2978 GDB breakpoint --- we may or not support Z0 breakpoints. If we
2979 do, we're be able to handle GDB breakpoints on top of internal
2980 breakpoints, by handling the internal breakpoint and still
2981 reporting the event to GDB. If we don't, we're out of luck, GDB
2982 won't see the breakpoint hit. */
2983 report_to_gdb = (!maybe_internal_trap
2984 || (current_thread->last_resume_kind == resume_step
2986 || event_child->stop_reason == TARGET_STOPPED_BY_WATCHPOINT
2987 || (!step_over_finished && !in_step_range
2988 && !bp_explains_trap && !trace_event)
2989 || (gdb_breakpoint_here (event_child->stop_pc)
2990 && gdb_condition_true_at_breakpoint (event_child->stop_pc)
2991 && gdb_no_commands_at_breakpoint (event_child->stop_pc)));
2993 run_breakpoint_commands (event_child->stop_pc);
2995 /* We found no reason GDB would want us to stop. We either hit one
2996 of our own breakpoints, or finished an internal step GDB
2997 shouldn't know about. */
3002 if (bp_explains_trap)
3003 debug_printf ("Hit a gdbserver breakpoint.\n");
3004 if (step_over_finished)
3005 debug_printf ("Step-over finished.\n");
3007 debug_printf ("Tracepoint event.\n");
3008 if (lwp_in_step_range (event_child))
3009 debug_printf ("Range stepping pc 0x%s [0x%s, 0x%s).\n",
3010 paddress (event_child->stop_pc),
3011 paddress (event_child->step_range_start),
3012 paddress (event_child->step_range_end));
3015 /* We're not reporting this breakpoint to GDB, so apply the
3016 decr_pc_after_break adjustment to the inferior's regcache
3019 if (the_low_target.set_pc != NULL)
3021 struct regcache *regcache
3022 = get_thread_regcache (current_thread, 1);
3023 (*the_low_target.set_pc) (regcache, event_child->stop_pc);
3026 /* We may have finished stepping over a breakpoint. If so,
3027 we've stopped and suspended all LWPs momentarily except the
3028 stepping one. This is where we resume them all again. We're
3029 going to keep waiting, so use proceed, which handles stepping
3030 over the next breakpoint. */
3032 debug_printf ("proceeding all threads.\n");
3034 if (step_over_finished)
3035 unsuspend_all_lwps (event_child);
3037 proceed_all_lwps ();
3038 return ignore_event (ourstatus);
3043 if (current_thread->last_resume_kind == resume_step)
3045 if (event_child->step_range_start == event_child->step_range_end)
3046 debug_printf ("GDB wanted to single-step, reporting event.\n");
3047 else if (!lwp_in_step_range (event_child))
3048 debug_printf ("Out of step range, reporting event.\n");
3050 if (event_child->stop_reason == TARGET_STOPPED_BY_WATCHPOINT)
3051 debug_printf ("Stopped by watchpoint.\n");
3052 else if (gdb_breakpoint_here (event_child->stop_pc))
3053 debug_printf ("Stopped by GDB breakpoint.\n");
3055 debug_printf ("Hit a non-gdbserver trap event.\n");
3058 /* Alright, we're going to report a stop. */
3060 if (!stabilizing_threads)
3062 /* In all-stop, stop all threads. */
3064 stop_all_lwps (0, NULL);
3066 /* If we're not waiting for a specific LWP, choose an event LWP
3067 from among those that have had events. Giving equal priority
3068 to all LWPs that have had events helps prevent
3070 if (ptid_equal (ptid, minus_one_ptid))
3072 event_child->status_pending_p = 1;
3073 event_child->status_pending = w;
3075 select_event_lwp (&event_child);
3077 /* current_thread and event_child must stay in sync. */
3078 current_thread = get_lwp_thread (event_child);
3080 event_child->status_pending_p = 0;
3081 w = event_child->status_pending;
3084 if (step_over_finished)
3088 /* If we were doing a step-over, all other threads but
3089 the stepping one had been paused in start_step_over,
3090 with their suspend counts incremented. We don't want
3091 to do a full unstop/unpause, because we're in
3092 all-stop mode (so we want threads stopped), but we
3093 still need to unsuspend the other threads, to
3094 decrement their `suspended' count back. */
3095 unsuspend_all_lwps (event_child);
3099 /* If we just finished a step-over, then all threads had
3100 been momentarily paused. In all-stop, that's fine,
3101 we want threads stopped by now anyway. In non-stop,
3102 we need to re-resume threads that GDB wanted to be
3104 unstop_all_lwps (1, event_child);
3108 /* Stabilize threads (move out of jump pads). */
3110 stabilize_threads ();
3114 /* If we just finished a step-over, then all threads had been
3115 momentarily paused. In all-stop, that's fine, we want
3116 threads stopped by now anyway. In non-stop, we need to
3117 re-resume threads that GDB wanted to be running. */
3118 if (step_over_finished)
3119 unstop_all_lwps (1, event_child);
3122 ourstatus->kind = TARGET_WAITKIND_STOPPED;
3124 /* Now that we've selected our final event LWP, un-adjust its PC if
3125 it was a software breakpoint, and the client doesn't know we can
3126 adjust the breakpoint ourselves. */
3127 if (event_child->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT
3128 && !swbreak_feature)
3130 int decr_pc = the_low_target.decr_pc_after_break;
3134 struct regcache *regcache
3135 = get_thread_regcache (current_thread, 1);
3136 (*the_low_target.set_pc) (regcache, event_child->stop_pc + decr_pc);
3140 if (current_thread->last_resume_kind == resume_stop
3141 && WSTOPSIG (w) == SIGSTOP)
3143 /* A thread that has been requested to stop by GDB with vCont;t,
3144 and it stopped cleanly, so report as SIG0. The use of
3145 SIGSTOP is an implementation detail. */
3146 ourstatus->value.sig = GDB_SIGNAL_0;
3148 else if (current_thread->last_resume_kind == resume_stop
3149 && WSTOPSIG (w) != SIGSTOP)
3151 /* A thread that has been requested to stop by GDB with vCont;t,
3152 but, it stopped for other reasons. */
3153 ourstatus->value.sig = gdb_signal_from_host (WSTOPSIG (w));
3157 ourstatus->value.sig = gdb_signal_from_host (WSTOPSIG (w));
3160 gdb_assert (ptid_equal (step_over_bkpt, null_ptid));
3164 debug_printf ("linux_wait_1 ret = %s, %d, %d\n",
3165 target_pid_to_str (ptid_of (current_thread)),
3166 ourstatus->kind, ourstatus->value.sig);
3170 return ptid_of (current_thread);
3173 /* Get rid of any pending event in the pipe. */
3175 async_file_flush (void)
3181 ret = read (linux_event_pipe[0], &buf, 1);
3182 while (ret >= 0 || (ret == -1 && errno == EINTR));
3185 /* Put something in the pipe, so the event loop wakes up. */
3187 async_file_mark (void)
3191 async_file_flush ();
3194 ret = write (linux_event_pipe[1], "+", 1);
3195 while (ret == 0 || (ret == -1 && errno == EINTR));
3197 /* Ignore EAGAIN. If the pipe is full, the event loop will already
3198 be awakened anyway. */
3202 linux_wait (ptid_t ptid,
3203 struct target_waitstatus *ourstatus, int target_options)
3207 /* Flush the async file first. */
3208 if (target_is_async_p ())
3209 async_file_flush ();
3213 event_ptid = linux_wait_1 (ptid, ourstatus, target_options);
3215 while ((target_options & TARGET_WNOHANG) == 0
3216 && ptid_equal (event_ptid, null_ptid)
3217 && ourstatus->kind == TARGET_WAITKIND_IGNORE);
3219 /* If at least one stop was reported, there may be more. A single
3220 SIGCHLD can signal more than one child stop. */
3221 if (target_is_async_p ()
3222 && (target_options & TARGET_WNOHANG) != 0
3223 && !ptid_equal (event_ptid, null_ptid))
3229 /* Send a signal to an LWP. */
3232 kill_lwp (unsigned long lwpid, int signo)
3234 /* Use tkill, if possible, in case we are using nptl threads. If tkill
3235 fails, then we are not using nptl threads and we should be using kill. */
3239 static int tkill_failed;
3246 ret = syscall (__NR_tkill, lwpid, signo);
3247 if (errno != ENOSYS)
3254 return kill (lwpid, signo);
3258 linux_stop_lwp (struct lwp_info *lwp)
3264 send_sigstop (struct lwp_info *lwp)
3268 pid = lwpid_of (get_lwp_thread (lwp));
3270 /* If we already have a pending stop signal for this process, don't
3272 if (lwp->stop_expected)
3275 debug_printf ("Have pending sigstop for lwp %d\n", pid);
3281 debug_printf ("Sending sigstop to lwp %d\n", pid);
3283 lwp->stop_expected = 1;
3284 kill_lwp (pid, SIGSTOP);
3288 send_sigstop_callback (struct inferior_list_entry *entry, void *except)
3290 struct thread_info *thread = (struct thread_info *) entry;
3291 struct lwp_info *lwp = get_thread_lwp (thread);
3293 /* Ignore EXCEPT. */
3304 /* Increment the suspend count of an LWP, and stop it, if not stopped
3307 suspend_and_send_sigstop_callback (struct inferior_list_entry *entry,
3310 struct thread_info *thread = (struct thread_info *) entry;
3311 struct lwp_info *lwp = get_thread_lwp (thread);
3313 /* Ignore EXCEPT. */
3319 return send_sigstop_callback (entry, except);
3323 mark_lwp_dead (struct lwp_info *lwp, int wstat)
3325 /* It's dead, really. */
3328 /* Store the exit status for later. */
3329 lwp->status_pending_p = 1;
3330 lwp->status_pending = wstat;
3332 /* Prevent trying to stop it. */
3335 /* No further stops are expected from a dead lwp. */
3336 lwp->stop_expected = 0;
3339 /* Wait for all children to stop for the SIGSTOPs we just queued. */
3342 wait_for_sigstop (void)
3344 struct thread_info *saved_thread;
3349 saved_thread = current_thread;
3350 if (saved_thread != NULL)
3351 saved_tid = saved_thread->entry.id;
3353 saved_tid = null_ptid; /* avoid bogus unused warning */
3356 debug_printf ("wait_for_sigstop: pulling events\n");
3358 /* Passing NULL_PTID as filter indicates we want all events to be
3359 left pending. Eventually this returns when there are no
3360 unwaited-for children left. */
3361 ret = linux_wait_for_event_filtered (minus_one_ptid, null_ptid,
3363 gdb_assert (ret == -1);
3365 if (saved_thread == NULL || linux_thread_alive (saved_tid))
3366 current_thread = saved_thread;
3370 debug_printf ("Previously current thread died.\n");
3374 /* We can't change the current inferior behind GDB's back,
3375 otherwise, a subsequent command may apply to the wrong
3377 current_thread = NULL;
3381 /* Set a valid thread as current. */
3382 set_desired_thread (0);
3387 /* Returns true if LWP ENTRY is stopped in a jump pad, and we can't
3388 move it out, because we need to report the stop event to GDB. For
3389 example, if the user puts a breakpoint in the jump pad, it's
3390 because she wants to debug it. */
3393 stuck_in_jump_pad_callback (struct inferior_list_entry *entry, void *data)
3395 struct thread_info *thread = (struct thread_info *) entry;
3396 struct lwp_info *lwp = get_thread_lwp (thread);
3398 gdb_assert (lwp->suspended == 0);
3399 gdb_assert (lwp->stopped);
3401 /* Allow debugging the jump pad, gdb_collect, etc.. */
3402 return (supports_fast_tracepoints ()
3403 && agent_loaded_p ()
3404 && (gdb_breakpoint_here (lwp->stop_pc)
3405 || lwp->stop_reason == TARGET_STOPPED_BY_WATCHPOINT
3406 || thread->last_resume_kind == resume_step)
3407 && linux_fast_tracepoint_collecting (lwp, NULL));
3411 move_out_of_jump_pad_callback (struct inferior_list_entry *entry)
3413 struct thread_info *thread = (struct thread_info *) entry;
3414 struct lwp_info *lwp = get_thread_lwp (thread);
3417 gdb_assert (lwp->suspended == 0);
3418 gdb_assert (lwp->stopped);
3420 wstat = lwp->status_pending_p ? &lwp->status_pending : NULL;
3422 /* Allow debugging the jump pad, gdb_collect, etc. */
3423 if (!gdb_breakpoint_here (lwp->stop_pc)
3424 && lwp->stop_reason != TARGET_STOPPED_BY_WATCHPOINT
3425 && thread->last_resume_kind != resume_step
3426 && maybe_move_out_of_jump_pad (lwp, wstat))
3429 debug_printf ("LWP %ld needs stabilizing (in jump pad)\n",
3434 lwp->status_pending_p = 0;
3435 enqueue_one_deferred_signal (lwp, wstat);
3438 debug_printf ("Signal %d for LWP %ld deferred "
3440 WSTOPSIG (*wstat), lwpid_of (thread));
3443 linux_resume_one_lwp (lwp, 0, 0, NULL);
3450 lwp_running (struct inferior_list_entry *entry, void *data)
3452 struct thread_info *thread = (struct thread_info *) entry;
3453 struct lwp_info *lwp = get_thread_lwp (thread);
3462 /* Stop all lwps that aren't stopped yet, except EXCEPT, if not NULL.
3463 If SUSPEND, then also increase the suspend count of every LWP,
3467 stop_all_lwps (int suspend, struct lwp_info *except)
3469 /* Should not be called recursively. */
3470 gdb_assert (stopping_threads == NOT_STOPPING_THREADS);
3475 debug_printf ("stop_all_lwps (%s, except=%s)\n",
3476 suspend ? "stop-and-suspend" : "stop",
3478 ? target_pid_to_str (ptid_of (get_lwp_thread (except)))
3482 stopping_threads = (suspend
3483 ? STOPPING_AND_SUSPENDING_THREADS
3484 : STOPPING_THREADS);
3487 find_inferior (&all_threads, suspend_and_send_sigstop_callback, except);
3489 find_inferior (&all_threads, send_sigstop_callback, except);
3490 wait_for_sigstop ();
3491 stopping_threads = NOT_STOPPING_THREADS;
3495 debug_printf ("stop_all_lwps done, setting stopping_threads "
3496 "back to !stopping\n");
3501 /* Resume execution of LWP. If STEP is nonzero, single-step it. If
3502 SIGNAL is nonzero, give it that signal. */
3505 linux_resume_one_lwp_throw (struct lwp_info *lwp,
3506 int step, int signal, siginfo_t *info)
3508 struct thread_info *thread = get_lwp_thread (lwp);
3509 struct thread_info *saved_thread;
3510 int fast_tp_collecting;
3512 if (lwp->stopped == 0)
3515 fast_tp_collecting = lwp->collecting_fast_tracepoint;
3517 gdb_assert (!stabilizing_threads || fast_tp_collecting);
3519 /* Cancel actions that rely on GDB not changing the PC (e.g., the
3520 user used the "jump" command, or "set $pc = foo"). */
3521 if (lwp->stop_pc != get_pc (lwp))
3523 /* Collecting 'while-stepping' actions doesn't make sense
3525 release_while_stepping_state_list (thread);
3528 /* If we have pending signals or status, and a new signal, enqueue the
3529 signal. Also enqueue the signal if we are waiting to reinsert a
3530 breakpoint; it will be picked up again below. */
3532 && (lwp->status_pending_p
3533 || lwp->pending_signals != NULL
3534 || lwp->bp_reinsert != 0
3535 || fast_tp_collecting))
3537 struct pending_signals *p_sig;
3538 p_sig = xmalloc (sizeof (*p_sig));
3539 p_sig->prev = lwp->pending_signals;
3540 p_sig->signal = signal;
3542 memset (&p_sig->info, 0, sizeof (siginfo_t));
3544 memcpy (&p_sig->info, info, sizeof (siginfo_t));
3545 lwp->pending_signals = p_sig;
3548 if (lwp->status_pending_p)
3551 debug_printf ("Not resuming lwp %ld (%s, signal %d, stop %s);"
3552 " has pending status\n",
3553 lwpid_of (thread), step ? "step" : "continue", signal,
3554 lwp->stop_expected ? "expected" : "not expected");
3558 saved_thread = current_thread;
3559 current_thread = thread;
3562 debug_printf ("Resuming lwp %ld (%s, signal %d, stop %s)\n",
3563 lwpid_of (thread), step ? "step" : "continue", signal,
3564 lwp->stop_expected ? "expected" : "not expected");
3566 /* This bit needs some thinking about. If we get a signal that
3567 we must report while a single-step reinsert is still pending,
3568 we often end up resuming the thread. It might be better to
3569 (ew) allow a stack of pending events; then we could be sure that
3570 the reinsert happened right away and not lose any signals.
3572 Making this stack would also shrink the window in which breakpoints are
3573 uninserted (see comment in linux_wait_for_lwp) but not enough for
3574 complete correctness, so it won't solve that problem. It may be
3575 worthwhile just to solve this one, however. */
3576 if (lwp->bp_reinsert != 0)
3579 debug_printf (" pending reinsert at 0x%s\n",
3580 paddress (lwp->bp_reinsert));
3582 if (can_hardware_single_step ())
3584 if (fast_tp_collecting == 0)
3587 fprintf (stderr, "BAD - reinserting but not stepping.\n");
3589 fprintf (stderr, "BAD - reinserting and suspended(%d).\n",
3596 /* Postpone any pending signal. It was enqueued above. */
3600 if (fast_tp_collecting == 1)
3603 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
3604 " (exit-jump-pad-bkpt)\n",
3607 /* Postpone any pending signal. It was enqueued above. */
3610 else if (fast_tp_collecting == 2)
3613 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
3614 " single-stepping\n",
3617 if (can_hardware_single_step ())
3621 internal_error (__FILE__, __LINE__,
3622 "moving out of jump pad single-stepping"
3623 " not implemented on this target");
3626 /* Postpone any pending signal. It was enqueued above. */
3630 /* If we have while-stepping actions in this thread set it stepping.
3631 If we have a signal to deliver, it may or may not be set to
3632 SIG_IGN, we don't know. Assume so, and allow collecting
3633 while-stepping into a signal handler. A possible smart thing to
3634 do would be to set an internal breakpoint at the signal return
3635 address, continue, and carry on catching this while-stepping
3636 action only when that breakpoint is hit. A future
3638 if (thread->while_stepping != NULL
3639 && can_hardware_single_step ())
3642 debug_printf ("lwp %ld has a while-stepping action -> forcing step.\n",
3647 if (the_low_target.get_pc != NULL)
3649 struct regcache *regcache = get_thread_regcache (current_thread, 1);
3651 lwp->stop_pc = (*the_low_target.get_pc) (regcache);
3655 debug_printf (" %s from pc 0x%lx\n", step ? "step" : "continue",
3656 (long) lwp->stop_pc);
3660 /* If we have pending signals, consume one unless we are trying to
3661 reinsert a breakpoint or we're trying to finish a fast tracepoint
3663 if (lwp->pending_signals != NULL
3664 && lwp->bp_reinsert == 0
3665 && fast_tp_collecting == 0)
3667 struct pending_signals **p_sig;
3669 p_sig = &lwp->pending_signals;
3670 while ((*p_sig)->prev != NULL)
3671 p_sig = &(*p_sig)->prev;
3673 signal = (*p_sig)->signal;
3674 if ((*p_sig)->info.si_signo != 0)
3675 ptrace (PTRACE_SETSIGINFO, lwpid_of (thread), (PTRACE_TYPE_ARG3) 0,
3682 if (the_low_target.prepare_to_resume != NULL)
3683 the_low_target.prepare_to_resume (lwp);
3685 regcache_invalidate_thread (thread);
3687 lwp->stepping = step;
3688 ptrace (step ? PTRACE_SINGLESTEP : PTRACE_CONT, lwpid_of (thread),
3689 (PTRACE_TYPE_ARG3) 0,
3690 /* Coerce to a uintptr_t first to avoid potential gcc warning
3691 of coercing an 8 byte integer to a 4 byte pointer. */
3692 (PTRACE_TYPE_ARG4) (uintptr_t) signal);
3694 current_thread = saved_thread;
3696 perror_with_name ("resuming thread");
3698 /* Successfully resumed. Clear state that no longer makes sense,
3699 and mark the LWP as running. Must not do this before resuming
3700 otherwise if that fails other code will be confused. E.g., we'd
3701 later try to stop the LWP and hang forever waiting for a stop
3702 status. Note that we must not throw after this is cleared,
3703 otherwise handle_zombie_lwp_error would get confused. */
3705 lwp->stop_reason = TARGET_STOPPED_BY_NO_REASON;
3708 /* Called when we try to resume a stopped LWP and that errors out. If
3709 the LWP is no longer in ptrace-stopped state (meaning it's zombie,
3710 or about to become), discard the error, clear any pending status
3711 the LWP may have, and return true (we'll collect the exit status
3712 soon enough). Otherwise, return false. */
3715 check_ptrace_stopped_lwp_gone (struct lwp_info *lp)
3717 struct thread_info *thread = get_lwp_thread (lp);
3719 /* If we get an error after resuming the LWP successfully, we'd
3720 confuse !T state for the LWP being gone. */
3721 gdb_assert (lp->stopped);
3723 /* We can't just check whether the LWP is in 'Z (Zombie)' state,
3724 because even if ptrace failed with ESRCH, the tracee may be "not
3725 yet fully dead", but already refusing ptrace requests. In that
3726 case the tracee has 'R (Running)' state for a little bit
3727 (observed in Linux 3.18). See also the note on ESRCH in the
3728 ptrace(2) man page. Instead, check whether the LWP has any state
3729 other than ptrace-stopped. */
3731 /* Don't assume anything if /proc/PID/status can't be read. */
3732 if (linux_proc_pid_is_trace_stopped_nowarn (lwpid_of (thread)) == 0)
3734 lp->stop_reason = TARGET_STOPPED_BY_NO_REASON;
3735 lp->status_pending_p = 0;
3741 /* Like linux_resume_one_lwp_throw, but no error is thrown if the LWP
3742 disappears while we try to resume it. */
3745 linux_resume_one_lwp (struct lwp_info *lwp,
3746 int step, int signal, siginfo_t *info)
3750 linux_resume_one_lwp_throw (lwp, step, signal, info);
3752 CATCH (ex, RETURN_MASK_ERROR)
3754 if (!check_ptrace_stopped_lwp_gone (lwp))
3755 throw_exception (ex);
3760 struct thread_resume_array
3762 struct thread_resume *resume;
3766 /* This function is called once per thread via find_inferior.
3767 ARG is a pointer to a thread_resume_array struct.
3768 We look up the thread specified by ENTRY in ARG, and mark the thread
3769 with a pointer to the appropriate resume request.
3771 This algorithm is O(threads * resume elements), but resume elements
3772 is small (and will remain small at least until GDB supports thread
3776 linux_set_resume_request (struct inferior_list_entry *entry, void *arg)
3778 struct thread_info *thread = (struct thread_info *) entry;
3779 struct lwp_info *lwp = get_thread_lwp (thread);
3781 struct thread_resume_array *r;
3785 for (ndx = 0; ndx < r->n; ndx++)
3787 ptid_t ptid = r->resume[ndx].thread;
3788 if (ptid_equal (ptid, minus_one_ptid)
3789 || ptid_equal (ptid, entry->id)
3790 /* Handle both 'pPID' and 'pPID.-1' as meaning 'all threads
3792 || (ptid_get_pid (ptid) == pid_of (thread)
3793 && (ptid_is_pid (ptid)
3794 || ptid_get_lwp (ptid) == -1)))
3796 if (r->resume[ndx].kind == resume_stop
3797 && thread->last_resume_kind == resume_stop)
3800 debug_printf ("already %s LWP %ld at GDB's request\n",
3801 (thread->last_status.kind
3802 == TARGET_WAITKIND_STOPPED)
3810 lwp->resume = &r->resume[ndx];
3811 thread->last_resume_kind = lwp->resume->kind;
3813 lwp->step_range_start = lwp->resume->step_range_start;
3814 lwp->step_range_end = lwp->resume->step_range_end;
3816 /* If we had a deferred signal to report, dequeue one now.
3817 This can happen if LWP gets more than one signal while
3818 trying to get out of a jump pad. */
3820 && !lwp->status_pending_p
3821 && dequeue_one_deferred_signal (lwp, &lwp->status_pending))
3823 lwp->status_pending_p = 1;
3826 debug_printf ("Dequeueing deferred signal %d for LWP %ld, "
3827 "leaving status pending.\n",
3828 WSTOPSIG (lwp->status_pending),
3836 /* No resume action for this thread. */
3842 /* find_inferior callback for linux_resume.
3843 Set *FLAG_P if this lwp has an interesting status pending. */
3846 resume_status_pending_p (struct inferior_list_entry *entry, void *flag_p)
3848 struct thread_info *thread = (struct thread_info *) entry;
3849 struct lwp_info *lwp = get_thread_lwp (thread);
3851 /* LWPs which will not be resumed are not interesting, because
3852 we might not wait for them next time through linux_wait. */
3853 if (lwp->resume == NULL)
3856 if (thread_still_has_status_pending_p (thread))
3857 * (int *) flag_p = 1;
3862 /* Return 1 if this lwp that GDB wants running is stopped at an
3863 internal breakpoint that we need to step over. It assumes that any
3864 required STOP_PC adjustment has already been propagated to the
3865 inferior's regcache. */
3868 need_step_over_p (struct inferior_list_entry *entry, void *dummy)
3870 struct thread_info *thread = (struct thread_info *) entry;
3871 struct lwp_info *lwp = get_thread_lwp (thread);
3872 struct thread_info *saved_thread;
3875 /* LWPs which will not be resumed are not interesting, because we
3876 might not wait for them next time through linux_wait. */
3881 debug_printf ("Need step over [LWP %ld]? Ignoring, not stopped\n",
3886 if (thread->last_resume_kind == resume_stop)
3889 debug_printf ("Need step over [LWP %ld]? Ignoring, should remain"
3895 gdb_assert (lwp->suspended >= 0);
3900 debug_printf ("Need step over [LWP %ld]? Ignoring, suspended\n",
3905 if (!lwp->need_step_over)
3908 debug_printf ("Need step over [LWP %ld]? No\n", lwpid_of (thread));
3911 if (lwp->status_pending_p)
3914 debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
3920 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
3924 /* If the PC has changed since we stopped, then don't do anything,
3925 and let the breakpoint/tracepoint be hit. This happens if, for
3926 instance, GDB handled the decr_pc_after_break subtraction itself,
3927 GDB is OOL stepping this thread, or the user has issued a "jump"
3928 command, or poked thread's registers herself. */
3929 if (pc != lwp->stop_pc)
3932 debug_printf ("Need step over [LWP %ld]? Cancelling, PC was changed. "
3933 "Old stop_pc was 0x%s, PC is now 0x%s\n",
3935 paddress (lwp->stop_pc), paddress (pc));
3937 lwp->need_step_over = 0;
3941 saved_thread = current_thread;
3942 current_thread = thread;
3944 /* We can only step over breakpoints we know about. */
3945 if (breakpoint_here (pc) || fast_tracepoint_jump_here (pc))
3947 /* Don't step over a breakpoint that GDB expects to hit
3948 though. If the condition is being evaluated on the target's side
3949 and it evaluate to false, step over this breakpoint as well. */
3950 if (gdb_breakpoint_here (pc)
3951 && gdb_condition_true_at_breakpoint (pc)
3952 && gdb_no_commands_at_breakpoint (pc))
3955 debug_printf ("Need step over [LWP %ld]? yes, but found"
3956 " GDB breakpoint at 0x%s; skipping step over\n",
3957 lwpid_of (thread), paddress (pc));
3959 current_thread = saved_thread;
3965 debug_printf ("Need step over [LWP %ld]? yes, "
3966 "found breakpoint at 0x%s\n",
3967 lwpid_of (thread), paddress (pc));
3969 /* We've found an lwp that needs stepping over --- return 1 so
3970 that find_inferior stops looking. */
3971 current_thread = saved_thread;
3973 /* If the step over is cancelled, this is set again. */
3974 lwp->need_step_over = 0;
3979 current_thread = saved_thread;
3982 debug_printf ("Need step over [LWP %ld]? No, no breakpoint found"
3984 lwpid_of (thread), paddress (pc));
3989 /* Start a step-over operation on LWP. When LWP stopped at a
3990 breakpoint, to make progress, we need to remove the breakpoint out
3991 of the way. If we let other threads run while we do that, they may
3992 pass by the breakpoint location and miss hitting it. To avoid
3993 that, a step-over momentarily stops all threads while LWP is
3994 single-stepped while the breakpoint is temporarily uninserted from
3995 the inferior. When the single-step finishes, we reinsert the
3996 breakpoint, and let all threads that are supposed to be running,
3999 On targets that don't support hardware single-step, we don't
4000 currently support full software single-stepping. Instead, we only
4001 support stepping over the thread event breakpoint, by asking the
4002 low target where to place a reinsert breakpoint. Since this
4003 routine assumes the breakpoint being stepped over is a thread event
4004 breakpoint, it usually assumes the return address of the current
4005 function is a good enough place to set the reinsert breakpoint. */
4008 start_step_over (struct lwp_info *lwp)
4010 struct thread_info *thread = get_lwp_thread (lwp);
4011 struct thread_info *saved_thread;
4016 debug_printf ("Starting step-over on LWP %ld. Stopping all threads\n",
4019 stop_all_lwps (1, lwp);
4020 gdb_assert (lwp->suspended == 0);
4023 debug_printf ("Done stopping all threads for step-over.\n");
4025 /* Note, we should always reach here with an already adjusted PC,
4026 either by GDB (if we're resuming due to GDB's request), or by our
4027 caller, if we just finished handling an internal breakpoint GDB
4028 shouldn't care about. */
4031 saved_thread = current_thread;
4032 current_thread = thread;
4034 lwp->bp_reinsert = pc;
4035 uninsert_breakpoints_at (pc);
4036 uninsert_fast_tracepoint_jumps_at (pc);
4038 if (can_hardware_single_step ())
4044 CORE_ADDR raddr = (*the_low_target.breakpoint_reinsert_addr) ();
4045 set_reinsert_breakpoint (raddr);
4049 current_thread = saved_thread;
4051 linux_resume_one_lwp (lwp, step, 0, NULL);
4053 /* Require next event from this LWP. */
4054 step_over_bkpt = thread->entry.id;
4058 /* Finish a step-over. Reinsert the breakpoint we had uninserted in
4059 start_step_over, if still there, and delete any reinsert
4060 breakpoints we've set, on non hardware single-step targets. */
4063 finish_step_over (struct lwp_info *lwp)
4065 if (lwp->bp_reinsert != 0)
4068 debug_printf ("Finished step over.\n");
4070 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
4071 may be no breakpoint to reinsert there by now. */
4072 reinsert_breakpoints_at (lwp->bp_reinsert);
4073 reinsert_fast_tracepoint_jumps_at (lwp->bp_reinsert);
4075 lwp->bp_reinsert = 0;
4077 /* Delete any software-single-step reinsert breakpoints. No
4078 longer needed. We don't have to worry about other threads
4079 hitting this trap, and later not being able to explain it,
4080 because we were stepping over a breakpoint, and we hold all
4081 threads but LWP stopped while doing that. */
4082 if (!can_hardware_single_step ())
4083 delete_reinsert_breakpoints ();
4085 step_over_bkpt = null_ptid;
4092 /* This function is called once per thread. We check the thread's resume
4093 request, which will tell us whether to resume, step, or leave the thread
4094 stopped; and what signal, if any, it should be sent.
4096 For threads which we aren't explicitly told otherwise, we preserve
4097 the stepping flag; this is used for stepping over gdbserver-placed
4100 If pending_flags was set in any thread, we queue any needed
4101 signals, since we won't actually resume. We already have a pending
4102 event to report, so we don't need to preserve any step requests;
4103 they should be re-issued if necessary. */
4106 linux_resume_one_thread (struct inferior_list_entry *entry, void *arg)
4108 struct thread_info *thread = (struct thread_info *) entry;
4109 struct lwp_info *lwp = get_thread_lwp (thread);
4111 int leave_all_stopped = * (int *) arg;
4114 if (lwp->resume == NULL)
4117 if (lwp->resume->kind == resume_stop)
4120 debug_printf ("resume_stop request for LWP %ld\n", lwpid_of (thread));
4125 debug_printf ("stopping LWP %ld\n", lwpid_of (thread));
4127 /* Stop the thread, and wait for the event asynchronously,
4128 through the event loop. */
4134 debug_printf ("already stopped LWP %ld\n",
4137 /* The LWP may have been stopped in an internal event that
4138 was not meant to be notified back to GDB (e.g., gdbserver
4139 breakpoint), so we should be reporting a stop event in
4142 /* If the thread already has a pending SIGSTOP, this is a
4143 no-op. Otherwise, something later will presumably resume
4144 the thread and this will cause it to cancel any pending
4145 operation, due to last_resume_kind == resume_stop. If
4146 the thread already has a pending status to report, we
4147 will still report it the next time we wait - see
4148 status_pending_p_callback. */
4150 /* If we already have a pending signal to report, then
4151 there's no need to queue a SIGSTOP, as this means we're
4152 midway through moving the LWP out of the jumppad, and we
4153 will report the pending signal as soon as that is
4155 if (lwp->pending_signals_to_report == NULL)
4159 /* For stop requests, we're done. */
4161 thread->last_status.kind = TARGET_WAITKIND_IGNORE;
4165 /* If this thread which is about to be resumed has a pending status,
4166 then don't resume any threads - we can just report the pending
4167 status. Make sure to queue any signals that would otherwise be
4168 sent. In all-stop mode, we do this decision based on if *any*
4169 thread has a pending status. If there's a thread that needs the
4170 step-over-breakpoint dance, then don't resume any other thread
4171 but that particular one. */
4172 leave_pending = (lwp->status_pending_p || leave_all_stopped);
4177 debug_printf ("resuming LWP %ld\n", lwpid_of (thread));
4179 step = (lwp->resume->kind == resume_step);
4180 linux_resume_one_lwp (lwp, step, lwp->resume->sig, NULL);
4185 debug_printf ("leaving LWP %ld stopped\n", lwpid_of (thread));
4187 /* If we have a new signal, enqueue the signal. */
4188 if (lwp->resume->sig != 0)
4190 struct pending_signals *p_sig;
4191 p_sig = xmalloc (sizeof (*p_sig));
4192 p_sig->prev = lwp->pending_signals;
4193 p_sig->signal = lwp->resume->sig;
4194 memset (&p_sig->info, 0, sizeof (siginfo_t));
4196 /* If this is the same signal we were previously stopped by,
4197 make sure to queue its siginfo. We can ignore the return
4198 value of ptrace; if it fails, we'll skip
4199 PTRACE_SETSIGINFO. */
4200 if (WIFSTOPPED (lwp->last_status)
4201 && WSTOPSIG (lwp->last_status) == lwp->resume->sig)
4202 ptrace (PTRACE_GETSIGINFO, lwpid_of (thread), (PTRACE_TYPE_ARG3) 0,
4205 lwp->pending_signals = p_sig;
4209 thread->last_status.kind = TARGET_WAITKIND_IGNORE;
4215 linux_resume (struct thread_resume *resume_info, size_t n)
4217 struct thread_resume_array array = { resume_info, n };
4218 struct thread_info *need_step_over = NULL;
4220 int leave_all_stopped;
4225 debug_printf ("linux_resume:\n");
4228 find_inferior (&all_threads, linux_set_resume_request, &array);
4230 /* If there is a thread which would otherwise be resumed, which has
4231 a pending status, then don't resume any threads - we can just
4232 report the pending status. Make sure to queue any signals that
4233 would otherwise be sent. In non-stop mode, we'll apply this
4234 logic to each thread individually. We consume all pending events
4235 before considering to start a step-over (in all-stop). */
4238 find_inferior (&all_threads, resume_status_pending_p, &any_pending);
4240 /* If there is a thread which would otherwise be resumed, which is
4241 stopped at a breakpoint that needs stepping over, then don't
4242 resume any threads - have it step over the breakpoint with all
4243 other threads stopped, then resume all threads again. Make sure
4244 to queue any signals that would otherwise be delivered or
4246 if (!any_pending && supports_breakpoints ())
4248 = (struct thread_info *) find_inferior (&all_threads,
4249 need_step_over_p, NULL);
4251 leave_all_stopped = (need_step_over != NULL || any_pending);
4255 if (need_step_over != NULL)
4256 debug_printf ("Not resuming all, need step over\n");
4257 else if (any_pending)
4258 debug_printf ("Not resuming, all-stop and found "
4259 "an LWP with pending status\n");
4261 debug_printf ("Resuming, no pending status or step over needed\n");
4264 /* Even if we're leaving threads stopped, queue all signals we'd
4265 otherwise deliver. */
4266 find_inferior (&all_threads, linux_resume_one_thread, &leave_all_stopped);
4269 start_step_over (get_thread_lwp (need_step_over));
4273 debug_printf ("linux_resume done\n");
4278 /* This function is called once per thread. We check the thread's
4279 last resume request, which will tell us whether to resume, step, or
4280 leave the thread stopped. Any signal the client requested to be
4281 delivered has already been enqueued at this point.
4283 If any thread that GDB wants running is stopped at an internal
4284 breakpoint that needs stepping over, we start a step-over operation
4285 on that particular thread, and leave all others stopped. */
4288 proceed_one_lwp (struct inferior_list_entry *entry, void *except)
4290 struct thread_info *thread = (struct thread_info *) entry;
4291 struct lwp_info *lwp = get_thread_lwp (thread);
4298 debug_printf ("proceed_one_lwp: lwp %ld\n", lwpid_of (thread));
4303 debug_printf (" LWP %ld already running\n", lwpid_of (thread));
4307 if (thread->last_resume_kind == resume_stop
4308 && thread->last_status.kind != TARGET_WAITKIND_IGNORE)
4311 debug_printf (" client wants LWP to remain %ld stopped\n",
4316 if (lwp->status_pending_p)
4319 debug_printf (" LWP %ld has pending status, leaving stopped\n",
4324 gdb_assert (lwp->suspended >= 0);
4329 debug_printf (" LWP %ld is suspended\n", lwpid_of (thread));
4333 if (thread->last_resume_kind == resume_stop
4334 && lwp->pending_signals_to_report == NULL
4335 && lwp->collecting_fast_tracepoint == 0)
4337 /* We haven't reported this LWP as stopped yet (otherwise, the
4338 last_status.kind check above would catch it, and we wouldn't
4339 reach here. This LWP may have been momentarily paused by a
4340 stop_all_lwps call while handling for example, another LWP's
4341 step-over. In that case, the pending expected SIGSTOP signal
4342 that was queued at vCont;t handling time will have already
4343 been consumed by wait_for_sigstop, and so we need to requeue
4344 another one here. Note that if the LWP already has a SIGSTOP
4345 pending, this is a no-op. */
4348 debug_printf ("Client wants LWP %ld to stop. "
4349 "Making sure it has a SIGSTOP pending\n",
4355 step = thread->last_resume_kind == resume_step;
4356 linux_resume_one_lwp (lwp, step, 0, NULL);
4361 unsuspend_and_proceed_one_lwp (struct inferior_list_entry *entry, void *except)
4363 struct thread_info *thread = (struct thread_info *) entry;
4364 struct lwp_info *lwp = get_thread_lwp (thread);
4370 gdb_assert (lwp->suspended >= 0);
4372 return proceed_one_lwp (entry, except);
4375 /* When we finish a step-over, set threads running again. If there's
4376 another thread that may need a step-over, now's the time to start
4377 it. Eventually, we'll move all threads past their breakpoints. */
4380 proceed_all_lwps (void)
4382 struct thread_info *need_step_over;
4384 /* If there is a thread which would otherwise be resumed, which is
4385 stopped at a breakpoint that needs stepping over, then don't
4386 resume any threads - have it step over the breakpoint with all
4387 other threads stopped, then resume all threads again. */
4389 if (supports_breakpoints ())
4392 = (struct thread_info *) find_inferior (&all_threads,
4393 need_step_over_p, NULL);
4395 if (need_step_over != NULL)
4398 debug_printf ("proceed_all_lwps: found "
4399 "thread %ld needing a step-over\n",
4400 lwpid_of (need_step_over));
4402 start_step_over (get_thread_lwp (need_step_over));
4408 debug_printf ("Proceeding, no step-over needed\n");
4410 find_inferior (&all_threads, proceed_one_lwp, NULL);
4413 /* Stopped LWPs that the client wanted to be running, that don't have
4414 pending statuses, are set to run again, except for EXCEPT, if not
4415 NULL. This undoes a stop_all_lwps call. */
4418 unstop_all_lwps (int unsuspend, struct lwp_info *except)
4424 debug_printf ("unstopping all lwps, except=(LWP %ld)\n",
4425 lwpid_of (get_lwp_thread (except)));
4427 debug_printf ("unstopping all lwps\n");
4431 find_inferior (&all_threads, unsuspend_and_proceed_one_lwp, except);
4433 find_inferior (&all_threads, proceed_one_lwp, except);
4437 debug_printf ("unstop_all_lwps done\n");
4443 #ifdef HAVE_LINUX_REGSETS
4445 #define use_linux_regsets 1
4447 /* Returns true if REGSET has been disabled. */
4450 regset_disabled (struct regsets_info *info, struct regset_info *regset)
4452 return (info->disabled_regsets != NULL
4453 && info->disabled_regsets[regset - info->regsets]);
4456 /* Disable REGSET. */
4459 disable_regset (struct regsets_info *info, struct regset_info *regset)
4463 dr_offset = regset - info->regsets;
4464 if (info->disabled_regsets == NULL)
4465 info->disabled_regsets = xcalloc (1, info->num_regsets);
4466 info->disabled_regsets[dr_offset] = 1;
4470 regsets_fetch_inferior_registers (struct regsets_info *regsets_info,
4471 struct regcache *regcache)
4473 struct regset_info *regset;
4474 int saw_general_regs = 0;
4478 pid = lwpid_of (current_thread);
4479 for (regset = regsets_info->regsets; regset->size >= 0; regset++)
4484 if (regset->size == 0 || regset_disabled (regsets_info, regset))
4487 buf = xmalloc (regset->size);
4489 nt_type = regset->nt_type;
4493 iov.iov_len = regset->size;
4494 data = (void *) &iov;
4500 res = ptrace (regset->get_request, pid,
4501 (PTRACE_TYPE_ARG3) (long) nt_type, data);
4503 res = ptrace (regset->get_request, pid, data, nt_type);
4509 /* If we get EIO on a regset, do not try it again for
4510 this process mode. */
4511 disable_regset (regsets_info, regset);
4513 else if (errno == ENODATA)
4515 /* ENODATA may be returned if the regset is currently
4516 not "active". This can happen in normal operation,
4517 so suppress the warning in this case. */
4522 sprintf (s, "ptrace(regsets_fetch_inferior_registers) PID=%d",
4529 if (regset->type == GENERAL_REGS)
4530 saw_general_regs = 1;
4531 regset->store_function (regcache, buf);
4535 if (saw_general_regs)
4542 regsets_store_inferior_registers (struct regsets_info *regsets_info,
4543 struct regcache *regcache)
4545 struct regset_info *regset;
4546 int saw_general_regs = 0;
4550 pid = lwpid_of (current_thread);
4551 for (regset = regsets_info->regsets; regset->size >= 0; regset++)
4556 if (regset->size == 0 || regset_disabled (regsets_info, regset)
4557 || regset->fill_function == NULL)
4560 buf = xmalloc (regset->size);
4562 /* First fill the buffer with the current register set contents,
4563 in case there are any items in the kernel's regset that are
4564 not in gdbserver's regcache. */
4566 nt_type = regset->nt_type;
4570 iov.iov_len = regset->size;
4571 data = (void *) &iov;
4577 res = ptrace (regset->get_request, pid,
4578 (PTRACE_TYPE_ARG3) (long) nt_type, data);
4580 res = ptrace (regset->get_request, pid, data, nt_type);
4585 /* Then overlay our cached registers on that. */
4586 regset->fill_function (regcache, buf);
4588 /* Only now do we write the register set. */
4590 res = ptrace (regset->set_request, pid,
4591 (PTRACE_TYPE_ARG3) (long) nt_type, data);
4593 res = ptrace (regset->set_request, pid, data, nt_type);
4601 /* If we get EIO on a regset, do not try it again for
4602 this process mode. */
4603 disable_regset (regsets_info, regset);
4605 else if (errno == ESRCH)
4607 /* At this point, ESRCH should mean the process is
4608 already gone, in which case we simply ignore attempts
4609 to change its registers. See also the related
4610 comment in linux_resume_one_lwp. */
4616 perror ("Warning: ptrace(regsets_store_inferior_registers)");
4619 else if (regset->type == GENERAL_REGS)
4620 saw_general_regs = 1;
4623 if (saw_general_regs)
4629 #else /* !HAVE_LINUX_REGSETS */
4631 #define use_linux_regsets 0
4632 #define regsets_fetch_inferior_registers(regsets_info, regcache) 1
4633 #define regsets_store_inferior_registers(regsets_info, regcache) 1
4637 /* Return 1 if register REGNO is supported by one of the regset ptrace
4638 calls or 0 if it has to be transferred individually. */
4641 linux_register_in_regsets (const struct regs_info *regs_info, int regno)
4643 unsigned char mask = 1 << (regno % 8);
4644 size_t index = regno / 8;
4646 return (use_linux_regsets
4647 && (regs_info->regset_bitmap == NULL
4648 || (regs_info->regset_bitmap[index] & mask) != 0));
4651 #ifdef HAVE_LINUX_USRREGS
4654 register_addr (const struct usrregs_info *usrregs, int regnum)
4658 if (regnum < 0 || regnum >= usrregs->num_regs)
4659 error ("Invalid register number %d.", regnum);
4661 addr = usrregs->regmap[regnum];
4666 /* Fetch one register. */
4668 fetch_register (const struct usrregs_info *usrregs,
4669 struct regcache *regcache, int regno)
4676 if (regno >= usrregs->num_regs)
4678 if ((*the_low_target.cannot_fetch_register) (regno))
4681 regaddr = register_addr (usrregs, regno);
4685 size = ((register_size (regcache->tdesc, regno)
4686 + sizeof (PTRACE_XFER_TYPE) - 1)
4687 & -sizeof (PTRACE_XFER_TYPE));
4688 buf = alloca (size);
4690 pid = lwpid_of (current_thread);
4691 for (i = 0; i < size; i += sizeof (PTRACE_XFER_TYPE))
4694 *(PTRACE_XFER_TYPE *) (buf + i) =
4695 ptrace (PTRACE_PEEKUSER, pid,
4696 /* Coerce to a uintptr_t first to avoid potential gcc warning
4697 of coercing an 8 byte integer to a 4 byte pointer. */
4698 (PTRACE_TYPE_ARG3) (uintptr_t) regaddr, (PTRACE_TYPE_ARG4) 0);
4699 regaddr += sizeof (PTRACE_XFER_TYPE);
4701 error ("reading register %d: %s", regno, strerror (errno));
4704 if (the_low_target.supply_ptrace_register)
4705 the_low_target.supply_ptrace_register (regcache, regno, buf);
4707 supply_register (regcache, regno, buf);
4710 /* Store one register. */
4712 store_register (const struct usrregs_info *usrregs,
4713 struct regcache *regcache, int regno)
4720 if (regno >= usrregs->num_regs)
4722 if ((*the_low_target.cannot_store_register) (regno))
4725 regaddr = register_addr (usrregs, regno);
4729 size = ((register_size (regcache->tdesc, regno)
4730 + sizeof (PTRACE_XFER_TYPE) - 1)
4731 & -sizeof (PTRACE_XFER_TYPE));
4732 buf = alloca (size);
4733 memset (buf, 0, size);
4735 if (the_low_target.collect_ptrace_register)
4736 the_low_target.collect_ptrace_register (regcache, regno, buf);
4738 collect_register (regcache, regno, buf);
4740 pid = lwpid_of (current_thread);
4741 for (i = 0; i < size; i += sizeof (PTRACE_XFER_TYPE))
4744 ptrace (PTRACE_POKEUSER, pid,
4745 /* Coerce to a uintptr_t first to avoid potential gcc warning
4746 about coercing an 8 byte integer to a 4 byte pointer. */
4747 (PTRACE_TYPE_ARG3) (uintptr_t) regaddr,
4748 (PTRACE_TYPE_ARG4) *(PTRACE_XFER_TYPE *) (buf + i));
4751 /* At this point, ESRCH should mean the process is
4752 already gone, in which case we simply ignore attempts
4753 to change its registers. See also the related
4754 comment in linux_resume_one_lwp. */
4758 if ((*the_low_target.cannot_store_register) (regno) == 0)
4759 error ("writing register %d: %s", regno, strerror (errno));
4761 regaddr += sizeof (PTRACE_XFER_TYPE);
4765 /* Fetch all registers, or just one, from the child process.
4766 If REGNO is -1, do this for all registers, skipping any that are
4767 assumed to have been retrieved by regsets_fetch_inferior_registers,
4768 unless ALL is non-zero.
4769 Otherwise, REGNO specifies which register (so we can save time). */
4771 usr_fetch_inferior_registers (const struct regs_info *regs_info,
4772 struct regcache *regcache, int regno, int all)
4774 struct usrregs_info *usr = regs_info->usrregs;
4778 for (regno = 0; regno < usr->num_regs; regno++)
4779 if (all || !linux_register_in_regsets (regs_info, regno))
4780 fetch_register (usr, regcache, regno);
4783 fetch_register (usr, regcache, regno);
4786 /* Store our register values back into the inferior.
4787 If REGNO is -1, do this for all registers, skipping any that are
4788 assumed to have been saved by regsets_store_inferior_registers,
4789 unless ALL is non-zero.
4790 Otherwise, REGNO specifies which register (so we can save time). */
4792 usr_store_inferior_registers (const struct regs_info *regs_info,
4793 struct regcache *regcache, int regno, int all)
4795 struct usrregs_info *usr = regs_info->usrregs;
4799 for (regno = 0; regno < usr->num_regs; regno++)
4800 if (all || !linux_register_in_regsets (regs_info, regno))
4801 store_register (usr, regcache, regno);
4804 store_register (usr, regcache, regno);
4807 #else /* !HAVE_LINUX_USRREGS */
4809 #define usr_fetch_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
4810 #define usr_store_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
4816 linux_fetch_registers (struct regcache *regcache, int regno)
4820 const struct regs_info *regs_info = (*the_low_target.regs_info) ();
4824 if (the_low_target.fetch_register != NULL
4825 && regs_info->usrregs != NULL)
4826 for (regno = 0; regno < regs_info->usrregs->num_regs; regno++)
4827 (*the_low_target.fetch_register) (regcache, regno);
4829 all = regsets_fetch_inferior_registers (regs_info->regsets_info, regcache);
4830 if (regs_info->usrregs != NULL)
4831 usr_fetch_inferior_registers (regs_info, regcache, -1, all);
4835 if (the_low_target.fetch_register != NULL
4836 && (*the_low_target.fetch_register) (regcache, regno))
4839 use_regsets = linux_register_in_regsets (regs_info, regno);
4841 all = regsets_fetch_inferior_registers (regs_info->regsets_info,
4843 if ((!use_regsets || all) && regs_info->usrregs != NULL)
4844 usr_fetch_inferior_registers (regs_info, regcache, regno, 1);
4849 linux_store_registers (struct regcache *regcache, int regno)
4853 const struct regs_info *regs_info = (*the_low_target.regs_info) ();
4857 all = regsets_store_inferior_registers (regs_info->regsets_info,
4859 if (regs_info->usrregs != NULL)
4860 usr_store_inferior_registers (regs_info, regcache, regno, all);
4864 use_regsets = linux_register_in_regsets (regs_info, regno);
4866 all = regsets_store_inferior_registers (regs_info->regsets_info,
4868 if ((!use_regsets || all) && regs_info->usrregs != NULL)
4869 usr_store_inferior_registers (regs_info, regcache, regno, 1);
4874 /* Copy LEN bytes from inferior's memory starting at MEMADDR
4875 to debugger memory starting at MYADDR. */
4878 linux_read_memory (CORE_ADDR memaddr, unsigned char *myaddr, int len)
4880 int pid = lwpid_of (current_thread);
4881 register PTRACE_XFER_TYPE *buffer;
4882 register CORE_ADDR addr;
4889 /* Try using /proc. Don't bother for one word. */
4890 if (len >= 3 * sizeof (long))
4894 /* We could keep this file open and cache it - possibly one per
4895 thread. That requires some juggling, but is even faster. */
4896 sprintf (filename, "/proc/%d/mem", pid);
4897 fd = open (filename, O_RDONLY | O_LARGEFILE);
4901 /* If pread64 is available, use it. It's faster if the kernel
4902 supports it (only one syscall), and it's 64-bit safe even on
4903 32-bit platforms (for instance, SPARC debugging a SPARC64
4906 bytes = pread64 (fd, myaddr, len, memaddr);
4909 if (lseek (fd, memaddr, SEEK_SET) != -1)
4910 bytes = read (fd, myaddr, len);
4917 /* Some data was read, we'll try to get the rest with ptrace. */
4927 /* Round starting address down to longword boundary. */
4928 addr = memaddr & -(CORE_ADDR) sizeof (PTRACE_XFER_TYPE);
4929 /* Round ending address up; get number of longwords that makes. */
4930 count = ((((memaddr + len) - addr) + sizeof (PTRACE_XFER_TYPE) - 1)
4931 / sizeof (PTRACE_XFER_TYPE));
4932 /* Allocate buffer of that many longwords. */
4933 buffer = (PTRACE_XFER_TYPE *) alloca (count * sizeof (PTRACE_XFER_TYPE));
4935 /* Read all the longwords */
4937 for (i = 0; i < count; i++, addr += sizeof (PTRACE_XFER_TYPE))
4939 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
4940 about coercing an 8 byte integer to a 4 byte pointer. */
4941 buffer[i] = ptrace (PTRACE_PEEKTEXT, pid,
4942 (PTRACE_TYPE_ARG3) (uintptr_t) addr,
4943 (PTRACE_TYPE_ARG4) 0);
4949 /* Copy appropriate bytes out of the buffer. */
4952 i *= sizeof (PTRACE_XFER_TYPE);
4953 i -= memaddr & (sizeof (PTRACE_XFER_TYPE) - 1);
4955 (char *) buffer + (memaddr & (sizeof (PTRACE_XFER_TYPE) - 1)),
4962 /* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
4963 memory at MEMADDR. On failure (cannot write to the inferior)
4964 returns the value of errno. Always succeeds if LEN is zero. */
4967 linux_write_memory (CORE_ADDR memaddr, const unsigned char *myaddr, int len)
4970 /* Round starting address down to longword boundary. */
4971 register CORE_ADDR addr = memaddr & -(CORE_ADDR) sizeof (PTRACE_XFER_TYPE);
4972 /* Round ending address up; get number of longwords that makes. */
4974 = (((memaddr + len) - addr) + sizeof (PTRACE_XFER_TYPE) - 1)
4975 / sizeof (PTRACE_XFER_TYPE);
4977 /* Allocate buffer of that many longwords. */
4978 register PTRACE_XFER_TYPE *buffer = (PTRACE_XFER_TYPE *)
4979 alloca (count * sizeof (PTRACE_XFER_TYPE));
4981 int pid = lwpid_of (current_thread);
4985 /* Zero length write always succeeds. */
4991 /* Dump up to four bytes. */
4992 unsigned int val = * (unsigned int *) myaddr;
4998 val = val & 0xffffff;
4999 debug_printf ("Writing %0*x to 0x%08lx\n", 2 * ((len < 4) ? len : 4),
5000 val, (long)memaddr);
5003 /* Fill start and end extra bytes of buffer with existing memory data. */
5006 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5007 about coercing an 8 byte integer to a 4 byte pointer. */
5008 buffer[0] = ptrace (PTRACE_PEEKTEXT, pid,
5009 (PTRACE_TYPE_ARG3) (uintptr_t) addr,
5010 (PTRACE_TYPE_ARG4) 0);
5018 = ptrace (PTRACE_PEEKTEXT, pid,
5019 /* Coerce to a uintptr_t first to avoid potential gcc warning
5020 about coercing an 8 byte integer to a 4 byte pointer. */
5021 (PTRACE_TYPE_ARG3) (uintptr_t) (addr + (count - 1)
5022 * sizeof (PTRACE_XFER_TYPE)),
5023 (PTRACE_TYPE_ARG4) 0);
5028 /* Copy data to be written over corresponding part of buffer. */
5030 memcpy ((char *) buffer + (memaddr & (sizeof (PTRACE_XFER_TYPE) - 1)),
5033 /* Write the entire buffer. */
5035 for (i = 0; i < count; i++, addr += sizeof (PTRACE_XFER_TYPE))
5038 ptrace (PTRACE_POKETEXT, pid,
5039 /* Coerce to a uintptr_t first to avoid potential gcc warning
5040 about coercing an 8 byte integer to a 4 byte pointer. */
5041 (PTRACE_TYPE_ARG3) (uintptr_t) addr,
5042 (PTRACE_TYPE_ARG4) buffer[i]);
5051 linux_look_up_symbols (void)
5053 #ifdef USE_THREAD_DB
5054 struct process_info *proc = current_process ();
5056 if (proc->priv->thread_db != NULL)
5059 /* If the kernel supports tracing clones, then we don't need to
5060 use the magic thread event breakpoint to learn about
5062 thread_db_init (!linux_supports_traceclone ());
5067 linux_request_interrupt (void)
5069 extern unsigned long signal_pid;
5071 /* Send a SIGINT to the process group. This acts just like the user
5072 typed a ^C on the controlling terminal. */
5073 kill (-signal_pid, SIGINT);
5076 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
5077 to debugger memory starting at MYADDR. */
5080 linux_read_auxv (CORE_ADDR offset, unsigned char *myaddr, unsigned int len)
5082 char filename[PATH_MAX];
5084 int pid = lwpid_of (current_thread);
5086 xsnprintf (filename, sizeof filename, "/proc/%d/auxv", pid);
5088 fd = open (filename, O_RDONLY);
5092 if (offset != (CORE_ADDR) 0
5093 && lseek (fd, (off_t) offset, SEEK_SET) != (off_t) offset)
5096 n = read (fd, myaddr, len);
5103 /* These breakpoint and watchpoint related wrapper functions simply
5104 pass on the function call if the target has registered a
5105 corresponding function. */
5108 linux_supports_z_point_type (char z_type)
5110 return (the_low_target.supports_z_point_type != NULL
5111 && the_low_target.supports_z_point_type (z_type));
5115 linux_insert_point (enum raw_bkpt_type type, CORE_ADDR addr,
5116 int size, struct raw_breakpoint *bp)
5118 if (type == raw_bkpt_type_sw)
5119 return insert_memory_breakpoint (bp);
5120 else if (the_low_target.insert_point != NULL)
5121 return the_low_target.insert_point (type, addr, size, bp);
5123 /* Unsupported (see target.h). */
5128 linux_remove_point (enum raw_bkpt_type type, CORE_ADDR addr,
5129 int size, struct raw_breakpoint *bp)
5131 if (type == raw_bkpt_type_sw)
5132 return remove_memory_breakpoint (bp);
5133 else if (the_low_target.remove_point != NULL)
5134 return the_low_target.remove_point (type, addr, size, bp);
5136 /* Unsupported (see target.h). */
5140 /* Implement the to_stopped_by_sw_breakpoint target_ops
5144 linux_stopped_by_sw_breakpoint (void)
5146 struct lwp_info *lwp = get_thread_lwp (current_thread);
5148 return (lwp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT);
5151 /* Implement the to_supports_stopped_by_sw_breakpoint target_ops
5155 linux_supports_stopped_by_sw_breakpoint (void)
5157 return USE_SIGTRAP_SIGINFO;
5160 /* Implement the to_stopped_by_hw_breakpoint target_ops
5164 linux_stopped_by_hw_breakpoint (void)
5166 struct lwp_info *lwp = get_thread_lwp (current_thread);
5168 return (lwp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT);
5171 /* Implement the to_supports_stopped_by_hw_breakpoint target_ops
5175 linux_supports_stopped_by_hw_breakpoint (void)
5177 return USE_SIGTRAP_SIGINFO;
5180 /* Implement the supports_conditional_breakpoints target_ops
5184 linux_supports_conditional_breakpoints (void)
5186 /* GDBserver needs to step over the breakpoint if the condition is
5187 false. GDBserver software single step is too simple, so disable
5188 conditional breakpoints if the target doesn't have hardware single
5190 return can_hardware_single_step ();
5194 linux_stopped_by_watchpoint (void)
5196 struct lwp_info *lwp = get_thread_lwp (current_thread);
5198 return lwp->stop_reason == TARGET_STOPPED_BY_WATCHPOINT;
5202 linux_stopped_data_address (void)
5204 struct lwp_info *lwp = get_thread_lwp (current_thread);
5206 return lwp->stopped_data_address;
5209 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
5210 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
5211 && defined(PT_TEXT_END_ADDR)
5213 /* This is only used for targets that define PT_TEXT_ADDR,
5214 PT_DATA_ADDR and PT_TEXT_END_ADDR. If those are not defined, supposedly
5215 the target has different ways of acquiring this information, like
5218 /* Under uClinux, programs are loaded at non-zero offsets, which we need
5219 to tell gdb about. */
5222 linux_read_offsets (CORE_ADDR *text_p, CORE_ADDR *data_p)
5224 unsigned long text, text_end, data;
5225 int pid = lwpid_of (current_thread);
5229 text = ptrace (PTRACE_PEEKUSER, pid, (PTRACE_TYPE_ARG3) PT_TEXT_ADDR,
5230 (PTRACE_TYPE_ARG4) 0);
5231 text_end = ptrace (PTRACE_PEEKUSER, pid, (PTRACE_TYPE_ARG3) PT_TEXT_END_ADDR,
5232 (PTRACE_TYPE_ARG4) 0);
5233 data = ptrace (PTRACE_PEEKUSER, pid, (PTRACE_TYPE_ARG3) PT_DATA_ADDR,
5234 (PTRACE_TYPE_ARG4) 0);
5238 /* Both text and data offsets produced at compile-time (and so
5239 used by gdb) are relative to the beginning of the program,
5240 with the data segment immediately following the text segment.
5241 However, the actual runtime layout in memory may put the data
5242 somewhere else, so when we send gdb a data base-address, we
5243 use the real data base address and subtract the compile-time
5244 data base-address from it (which is just the length of the
5245 text segment). BSS immediately follows data in both
5248 *data_p = data - (text_end - text);
5257 linux_qxfer_osdata (const char *annex,
5258 unsigned char *readbuf, unsigned const char *writebuf,
5259 CORE_ADDR offset, int len)
5261 return linux_common_xfer_osdata (annex, readbuf, offset, len);
5264 /* Convert a native/host siginfo object, into/from the siginfo in the
5265 layout of the inferiors' architecture. */
5268 siginfo_fixup (siginfo_t *siginfo, void *inf_siginfo, int direction)
5272 if (the_low_target.siginfo_fixup != NULL)
5273 done = the_low_target.siginfo_fixup (siginfo, inf_siginfo, direction);
5275 /* If there was no callback, or the callback didn't do anything,
5276 then just do a straight memcpy. */
5280 memcpy (siginfo, inf_siginfo, sizeof (siginfo_t));
5282 memcpy (inf_siginfo, siginfo, sizeof (siginfo_t));
5287 linux_xfer_siginfo (const char *annex, unsigned char *readbuf,
5288 unsigned const char *writebuf, CORE_ADDR offset, int len)
5292 char inf_siginfo[sizeof (siginfo_t)];
5294 if (current_thread == NULL)
5297 pid = lwpid_of (current_thread);
5300 debug_printf ("%s siginfo for lwp %d.\n",
5301 readbuf != NULL ? "Reading" : "Writing",
5304 if (offset >= sizeof (siginfo))
5307 if (ptrace (PTRACE_GETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo) != 0)
5310 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
5311 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
5312 inferior with a 64-bit GDBSERVER should look the same as debugging it
5313 with a 32-bit GDBSERVER, we need to convert it. */
5314 siginfo_fixup (&siginfo, inf_siginfo, 0);
5316 if (offset + len > sizeof (siginfo))
5317 len = sizeof (siginfo) - offset;
5319 if (readbuf != NULL)
5320 memcpy (readbuf, inf_siginfo + offset, len);
5323 memcpy (inf_siginfo + offset, writebuf, len);
5325 /* Convert back to ptrace layout before flushing it out. */
5326 siginfo_fixup (&siginfo, inf_siginfo, 1);
5328 if (ptrace (PTRACE_SETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo) != 0)
5335 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
5336 so we notice when children change state; as the handler for the
5337 sigsuspend in my_waitpid. */
5340 sigchld_handler (int signo)
5342 int old_errno = errno;
5348 /* fprintf is not async-signal-safe, so call write
5350 if (write (2, "sigchld_handler\n",
5351 sizeof ("sigchld_handler\n") - 1) < 0)
5352 break; /* just ignore */
5356 if (target_is_async_p ())
5357 async_file_mark (); /* trigger a linux_wait */
5363 linux_supports_non_stop (void)
5369 linux_async (int enable)
5371 int previous = target_is_async_p ();
5374 debug_printf ("linux_async (%d), previous=%d\n",
5377 if (previous != enable)
5380 sigemptyset (&mask);
5381 sigaddset (&mask, SIGCHLD);
5383 sigprocmask (SIG_BLOCK, &mask, NULL);
5387 if (pipe (linux_event_pipe) == -1)
5389 linux_event_pipe[0] = -1;
5390 linux_event_pipe[1] = -1;
5391 sigprocmask (SIG_UNBLOCK, &mask, NULL);
5393 warning ("creating event pipe failed.");
5397 fcntl (linux_event_pipe[0], F_SETFL, O_NONBLOCK);
5398 fcntl (linux_event_pipe[1], F_SETFL, O_NONBLOCK);
5400 /* Register the event loop handler. */
5401 add_file_handler (linux_event_pipe[0],
5402 handle_target_event, NULL);
5404 /* Always trigger a linux_wait. */
5409 delete_file_handler (linux_event_pipe[0]);
5411 close (linux_event_pipe[0]);
5412 close (linux_event_pipe[1]);
5413 linux_event_pipe[0] = -1;
5414 linux_event_pipe[1] = -1;
5417 sigprocmask (SIG_UNBLOCK, &mask, NULL);
5424 linux_start_non_stop (int nonstop)
5426 /* Register or unregister from event-loop accordingly. */
5427 linux_async (nonstop);
5429 if (target_is_async_p () != (nonstop != 0))
5436 linux_supports_multi_process (void)
5441 /* Check if fork events are supported. */
5444 linux_supports_fork_events (void)
5446 return linux_supports_tracefork ();
5449 /* Check if vfork events are supported. */
5452 linux_supports_vfork_events (void)
5454 return linux_supports_tracefork ();
5458 linux_supports_disable_randomization (void)
5460 #ifdef HAVE_PERSONALITY
5468 linux_supports_agent (void)
5474 linux_supports_range_stepping (void)
5476 if (*the_low_target.supports_range_stepping == NULL)
5479 return (*the_low_target.supports_range_stepping) ();
5482 /* Enumerate spufs IDs for process PID. */
5484 spu_enumerate_spu_ids (long pid, unsigned char *buf, CORE_ADDR offset, int len)
5490 struct dirent *entry;
5492 sprintf (path, "/proc/%ld/fd", pid);
5493 dir = opendir (path);
5498 while ((entry = readdir (dir)) != NULL)
5504 fd = atoi (entry->d_name);
5508 sprintf (path, "/proc/%ld/fd/%d", pid, fd);
5509 if (stat (path, &st) != 0)
5511 if (!S_ISDIR (st.st_mode))
5514 if (statfs (path, &stfs) != 0)
5516 if (stfs.f_type != SPUFS_MAGIC)
5519 if (pos >= offset && pos + 4 <= offset + len)
5521 *(unsigned int *)(buf + pos - offset) = fd;
5531 /* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
5532 object type, using the /proc file system. */
5534 linux_qxfer_spu (const char *annex, unsigned char *readbuf,
5535 unsigned const char *writebuf,
5536 CORE_ADDR offset, int len)
5538 long pid = lwpid_of (current_thread);
5543 if (!writebuf && !readbuf)
5551 return spu_enumerate_spu_ids (pid, readbuf, offset, len);
5554 sprintf (buf, "/proc/%ld/fd/%s", pid, annex);
5555 fd = open (buf, writebuf? O_WRONLY : O_RDONLY);
5560 && lseek (fd, (off_t) offset, SEEK_SET) != (off_t) offset)
5567 ret = write (fd, writebuf, (size_t) len);
5569 ret = read (fd, readbuf, (size_t) len);
5575 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
5576 struct target_loadseg
5578 /* Core address to which the segment is mapped. */
5580 /* VMA recorded in the program header. */
5582 /* Size of this segment in memory. */
5586 # if defined PT_GETDSBT
5587 struct target_loadmap
5589 /* Protocol version number, must be zero. */
5591 /* Pointer to the DSBT table, its size, and the DSBT index. */
5592 unsigned *dsbt_table;
5593 unsigned dsbt_size, dsbt_index;
5594 /* Number of segments in this map. */
5596 /* The actual memory map. */
5597 struct target_loadseg segs[/*nsegs*/];
5599 # define LINUX_LOADMAP PT_GETDSBT
5600 # define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
5601 # define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
5603 struct target_loadmap
5605 /* Protocol version number, must be zero. */
5607 /* Number of segments in this map. */
5609 /* The actual memory map. */
5610 struct target_loadseg segs[/*nsegs*/];
5612 # define LINUX_LOADMAP PTRACE_GETFDPIC
5613 # define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
5614 # define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
5618 linux_read_loadmap (const char *annex, CORE_ADDR offset,
5619 unsigned char *myaddr, unsigned int len)
5621 int pid = lwpid_of (current_thread);
5623 struct target_loadmap *data = NULL;
5624 unsigned int actual_length, copy_length;
5626 if (strcmp (annex, "exec") == 0)
5627 addr = (int) LINUX_LOADMAP_EXEC;
5628 else if (strcmp (annex, "interp") == 0)
5629 addr = (int) LINUX_LOADMAP_INTERP;
5633 if (ptrace (LINUX_LOADMAP, pid, addr, &data) != 0)
5639 actual_length = sizeof (struct target_loadmap)
5640 + sizeof (struct target_loadseg) * data->nsegs;
5642 if (offset < 0 || offset > actual_length)
5645 copy_length = actual_length - offset < len ? actual_length - offset : len;
5646 memcpy (myaddr, (char *) data + offset, copy_length);
5650 # define linux_read_loadmap NULL
5651 #endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
5654 linux_process_qsupported (const char *query)
5656 if (the_low_target.process_qsupported != NULL)
5657 the_low_target.process_qsupported (query);
5661 linux_supports_tracepoints (void)
5663 if (*the_low_target.supports_tracepoints == NULL)
5666 return (*the_low_target.supports_tracepoints) ();
5670 linux_read_pc (struct regcache *regcache)
5672 if (the_low_target.get_pc == NULL)
5675 return (*the_low_target.get_pc) (regcache);
5679 linux_write_pc (struct regcache *regcache, CORE_ADDR pc)
5681 gdb_assert (the_low_target.set_pc != NULL);
5683 (*the_low_target.set_pc) (regcache, pc);
5687 linux_thread_stopped (struct thread_info *thread)
5689 return get_thread_lwp (thread)->stopped;
5692 /* This exposes stop-all-threads functionality to other modules. */
5695 linux_pause_all (int freeze)
5697 stop_all_lwps (freeze, NULL);
5700 /* This exposes unstop-all-threads functionality to other gdbserver
5704 linux_unpause_all (int unfreeze)
5706 unstop_all_lwps (unfreeze, NULL);
5710 linux_prepare_to_access_memory (void)
5712 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
5715 linux_pause_all (1);
5720 linux_done_accessing_memory (void)
5722 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
5725 linux_unpause_all (1);
5729 linux_install_fast_tracepoint_jump_pad (CORE_ADDR tpoint, CORE_ADDR tpaddr,
5730 CORE_ADDR collector,
5733 CORE_ADDR *jump_entry,
5734 CORE_ADDR *trampoline,
5735 ULONGEST *trampoline_size,
5736 unsigned char *jjump_pad_insn,
5737 ULONGEST *jjump_pad_insn_size,
5738 CORE_ADDR *adjusted_insn_addr,
5739 CORE_ADDR *adjusted_insn_addr_end,
5742 return (*the_low_target.install_fast_tracepoint_jump_pad)
5743 (tpoint, tpaddr, collector, lockaddr, orig_size,
5744 jump_entry, trampoline, trampoline_size,
5745 jjump_pad_insn, jjump_pad_insn_size,
5746 adjusted_insn_addr, adjusted_insn_addr_end,
5750 static struct emit_ops *
5751 linux_emit_ops (void)
5753 if (the_low_target.emit_ops != NULL)
5754 return (*the_low_target.emit_ops) ();
5760 linux_get_min_fast_tracepoint_insn_len (void)
5762 return (*the_low_target.get_min_fast_tracepoint_insn_len) ();
5765 /* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
5768 get_phdr_phnum_from_proc_auxv (const int pid, const int is_elf64,
5769 CORE_ADDR *phdr_memaddr, int *num_phdr)
5771 char filename[PATH_MAX];
5773 const int auxv_size = is_elf64
5774 ? sizeof (Elf64_auxv_t) : sizeof (Elf32_auxv_t);
5775 char buf[sizeof (Elf64_auxv_t)]; /* The larger of the two. */
5777 xsnprintf (filename, sizeof filename, "/proc/%d/auxv", pid);
5779 fd = open (filename, O_RDONLY);
5785 while (read (fd, buf, auxv_size) == auxv_size
5786 && (*phdr_memaddr == 0 || *num_phdr == 0))
5790 Elf64_auxv_t *const aux = (Elf64_auxv_t *) buf;
5792 switch (aux->a_type)
5795 *phdr_memaddr = aux->a_un.a_val;
5798 *num_phdr = aux->a_un.a_val;
5804 Elf32_auxv_t *const aux = (Elf32_auxv_t *) buf;
5806 switch (aux->a_type)
5809 *phdr_memaddr = aux->a_un.a_val;
5812 *num_phdr = aux->a_un.a_val;
5820 if (*phdr_memaddr == 0 || *num_phdr == 0)
5822 warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
5823 "phdr_memaddr = %ld, phdr_num = %d",
5824 (long) *phdr_memaddr, *num_phdr);
5831 /* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
5834 get_dynamic (const int pid, const int is_elf64)
5836 CORE_ADDR phdr_memaddr, relocation;
5838 unsigned char *phdr_buf;
5839 const int phdr_size = is_elf64 ? sizeof (Elf64_Phdr) : sizeof (Elf32_Phdr);
5841 if (get_phdr_phnum_from_proc_auxv (pid, is_elf64, &phdr_memaddr, &num_phdr))
5844 gdb_assert (num_phdr < 100); /* Basic sanity check. */
5845 phdr_buf = alloca (num_phdr * phdr_size);
5847 if (linux_read_memory (phdr_memaddr, phdr_buf, num_phdr * phdr_size))
5850 /* Compute relocation: it is expected to be 0 for "regular" executables,
5851 non-zero for PIE ones. */
5853 for (i = 0; relocation == -1 && i < num_phdr; i++)
5856 Elf64_Phdr *const p = (Elf64_Phdr *) (phdr_buf + i * phdr_size);
5858 if (p->p_type == PT_PHDR)
5859 relocation = phdr_memaddr - p->p_vaddr;
5863 Elf32_Phdr *const p = (Elf32_Phdr *) (phdr_buf + i * phdr_size);
5865 if (p->p_type == PT_PHDR)
5866 relocation = phdr_memaddr - p->p_vaddr;
5869 if (relocation == -1)
5871 /* PT_PHDR is optional, but necessary for PIE in general. Fortunately
5872 any real world executables, including PIE executables, have always
5873 PT_PHDR present. PT_PHDR is not present in some shared libraries or
5874 in fpc (Free Pascal 2.4) binaries but neither of those have a need for
5875 or present DT_DEBUG anyway (fpc binaries are statically linked).
5877 Therefore if there exists DT_DEBUG there is always also PT_PHDR.
5879 GDB could find RELOCATION also from AT_ENTRY - e_entry. */
5884 for (i = 0; i < num_phdr; i++)
5888 Elf64_Phdr *const p = (Elf64_Phdr *) (phdr_buf + i * phdr_size);
5890 if (p->p_type == PT_DYNAMIC)
5891 return p->p_vaddr + relocation;
5895 Elf32_Phdr *const p = (Elf32_Phdr *) (phdr_buf + i * phdr_size);
5897 if (p->p_type == PT_DYNAMIC)
5898 return p->p_vaddr + relocation;
5905 /* Return &_r_debug in the inferior, or -1 if not present. Return value
5906 can be 0 if the inferior does not yet have the library list initialized.
5907 We look for DT_MIPS_RLD_MAP first. MIPS executables use this instead of
5908 DT_DEBUG, although they sometimes contain an unused DT_DEBUG entry too. */
5911 get_r_debug (const int pid, const int is_elf64)
5913 CORE_ADDR dynamic_memaddr;
5914 const int dyn_size = is_elf64 ? sizeof (Elf64_Dyn) : sizeof (Elf32_Dyn);
5915 unsigned char buf[sizeof (Elf64_Dyn)]; /* The larger of the two. */
5918 dynamic_memaddr = get_dynamic (pid, is_elf64);
5919 if (dynamic_memaddr == 0)
5922 while (linux_read_memory (dynamic_memaddr, buf, dyn_size) == 0)
5926 Elf64_Dyn *const dyn = (Elf64_Dyn *) buf;
5927 #ifdef DT_MIPS_RLD_MAP
5931 unsigned char buf[sizeof (Elf64_Xword)];
5935 if (dyn->d_tag == DT_MIPS_RLD_MAP)
5937 if (linux_read_memory (dyn->d_un.d_val,
5938 rld_map.buf, sizeof (rld_map.buf)) == 0)
5943 #endif /* DT_MIPS_RLD_MAP */
5945 if (dyn->d_tag == DT_DEBUG && map == -1)
5946 map = dyn->d_un.d_val;
5948 if (dyn->d_tag == DT_NULL)
5953 Elf32_Dyn *const dyn = (Elf32_Dyn *) buf;
5954 #ifdef DT_MIPS_RLD_MAP
5958 unsigned char buf[sizeof (Elf32_Word)];
5962 if (dyn->d_tag == DT_MIPS_RLD_MAP)
5964 if (linux_read_memory (dyn->d_un.d_val,
5965 rld_map.buf, sizeof (rld_map.buf)) == 0)
5970 #endif /* DT_MIPS_RLD_MAP */
5972 if (dyn->d_tag == DT_DEBUG && map == -1)
5973 map = dyn->d_un.d_val;
5975 if (dyn->d_tag == DT_NULL)
5979 dynamic_memaddr += dyn_size;
5985 /* Read one pointer from MEMADDR in the inferior. */
5988 read_one_ptr (CORE_ADDR memaddr, CORE_ADDR *ptr, int ptr_size)
5992 /* Go through a union so this works on either big or little endian
5993 hosts, when the inferior's pointer size is smaller than the size
5994 of CORE_ADDR. It is assumed the inferior's endianness is the
5995 same of the superior's. */
5998 CORE_ADDR core_addr;
6003 ret = linux_read_memory (memaddr, &addr.uc, ptr_size);
6006 if (ptr_size == sizeof (CORE_ADDR))
6007 *ptr = addr.core_addr;
6008 else if (ptr_size == sizeof (unsigned int))
6011 gdb_assert_not_reached ("unhandled pointer size");
6016 struct link_map_offsets
6018 /* Offset and size of r_debug.r_version. */
6019 int r_version_offset;
6021 /* Offset and size of r_debug.r_map. */
6024 /* Offset to l_addr field in struct link_map. */
6027 /* Offset to l_name field in struct link_map. */
6030 /* Offset to l_ld field in struct link_map. */
6033 /* Offset to l_next field in struct link_map. */
6036 /* Offset to l_prev field in struct link_map. */
6040 /* Construct qXfer:libraries-svr4:read reply. */
6043 linux_qxfer_libraries_svr4 (const char *annex, unsigned char *readbuf,
6044 unsigned const char *writebuf,
6045 CORE_ADDR offset, int len)
6048 unsigned document_len;
6049 struct process_info_private *const priv = current_process ()->priv;
6050 char filename[PATH_MAX];
6053 static const struct link_map_offsets lmo_32bit_offsets =
6055 0, /* r_version offset. */
6056 4, /* r_debug.r_map offset. */
6057 0, /* l_addr offset in link_map. */
6058 4, /* l_name offset in link_map. */
6059 8, /* l_ld offset in link_map. */
6060 12, /* l_next offset in link_map. */
6061 16 /* l_prev offset in link_map. */
6064 static const struct link_map_offsets lmo_64bit_offsets =
6066 0, /* r_version offset. */
6067 8, /* r_debug.r_map offset. */
6068 0, /* l_addr offset in link_map. */
6069 8, /* l_name offset in link_map. */
6070 16, /* l_ld offset in link_map. */
6071 24, /* l_next offset in link_map. */
6072 32 /* l_prev offset in link_map. */
6074 const struct link_map_offsets *lmo;
6075 unsigned int machine;
6077 CORE_ADDR lm_addr = 0, lm_prev = 0;
6078 int allocated = 1024;
6080 CORE_ADDR l_name, l_addr, l_ld, l_next, l_prev;
6081 int header_done = 0;
6083 if (writebuf != NULL)
6085 if (readbuf == NULL)
6088 pid = lwpid_of (current_thread);
6089 xsnprintf (filename, sizeof filename, "/proc/%d/exe", pid);
6090 is_elf64 = elf_64_file_p (filename, &machine);
6091 lmo = is_elf64 ? &lmo_64bit_offsets : &lmo_32bit_offsets;
6092 ptr_size = is_elf64 ? 8 : 4;
6094 while (annex[0] != '\0')
6100 sep = strchr (annex, '=');
6105 if (len == 5 && startswith (annex, "start"))
6107 else if (len == 4 && startswith (annex, "prev"))
6111 annex = strchr (sep, ';');
6118 annex = decode_address_to_semicolon (addrp, sep + 1);
6125 if (priv->r_debug == 0)
6126 priv->r_debug = get_r_debug (pid, is_elf64);
6128 /* We failed to find DT_DEBUG. Such situation will not change
6129 for this inferior - do not retry it. Report it to GDB as
6130 E01, see for the reasons at the GDB solib-svr4.c side. */
6131 if (priv->r_debug == (CORE_ADDR) -1)
6134 if (priv->r_debug != 0)
6136 if (linux_read_memory (priv->r_debug + lmo->r_version_offset,
6137 (unsigned char *) &r_version,
6138 sizeof (r_version)) != 0
6141 warning ("unexpected r_debug version %d", r_version);
6143 else if (read_one_ptr (priv->r_debug + lmo->r_map_offset,
6144 &lm_addr, ptr_size) != 0)
6146 warning ("unable to read r_map from 0x%lx",
6147 (long) priv->r_debug + lmo->r_map_offset);
6152 document = xmalloc (allocated);
6153 strcpy (document, "<library-list-svr4 version=\"1.0\"");
6154 p = document + strlen (document);
6157 && read_one_ptr (lm_addr + lmo->l_name_offset,
6158 &l_name, ptr_size) == 0
6159 && read_one_ptr (lm_addr + lmo->l_addr_offset,
6160 &l_addr, ptr_size) == 0
6161 && read_one_ptr (lm_addr + lmo->l_ld_offset,
6162 &l_ld, ptr_size) == 0
6163 && read_one_ptr (lm_addr + lmo->l_prev_offset,
6164 &l_prev, ptr_size) == 0
6165 && read_one_ptr (lm_addr + lmo->l_next_offset,
6166 &l_next, ptr_size) == 0)
6168 unsigned char libname[PATH_MAX];
6170 if (lm_prev != l_prev)
6172 warning ("Corrupted shared library list: 0x%lx != 0x%lx",
6173 (long) lm_prev, (long) l_prev);
6177 /* Ignore the first entry even if it has valid name as the first entry
6178 corresponds to the main executable. The first entry should not be
6179 skipped if the dynamic loader was loaded late by a static executable
6180 (see solib-svr4.c parameter ignore_first). But in such case the main
6181 executable does not have PT_DYNAMIC present and this function already
6182 exited above due to failed get_r_debug. */
6185 sprintf (p, " main-lm=\"0x%lx\"", (unsigned long) lm_addr);
6190 /* Not checking for error because reading may stop before
6191 we've got PATH_MAX worth of characters. */
6193 linux_read_memory (l_name, libname, sizeof (libname) - 1);
6194 libname[sizeof (libname) - 1] = '\0';
6195 if (libname[0] != '\0')
6197 /* 6x the size for xml_escape_text below. */
6198 size_t len = 6 * strlen ((char *) libname);
6203 /* Terminate `<library-list-svr4'. */
6208 while (allocated < p - document + len + 200)
6210 /* Expand to guarantee sufficient storage. */
6211 uintptr_t document_len = p - document;
6213 document = xrealloc (document, 2 * allocated);
6215 p = document + document_len;
6218 name = xml_escape_text ((char *) libname);
6219 p += sprintf (p, "<library name=\"%s\" lm=\"0x%lx\" "
6220 "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
6221 name, (unsigned long) lm_addr,
6222 (unsigned long) l_addr, (unsigned long) l_ld);
6233 /* Empty list; terminate `<library-list-svr4'. */
6237 strcpy (p, "</library-list-svr4>");
6239 document_len = strlen (document);
6240 if (offset < document_len)
6241 document_len -= offset;
6244 if (len > document_len)
6247 memcpy (readbuf, document + offset, len);
6253 #ifdef HAVE_LINUX_BTRACE
6255 /* See to_enable_btrace target method. */
6257 static struct btrace_target_info *
6258 linux_low_enable_btrace (ptid_t ptid, const struct btrace_config *conf)
6260 struct btrace_target_info *tinfo;
6262 tinfo = linux_enable_btrace (ptid, conf);
6264 if (tinfo != NULL && tinfo->ptr_bits == 0)
6266 struct thread_info *thread = find_thread_ptid (ptid);
6267 struct regcache *regcache = get_thread_regcache (thread, 0);
6269 tinfo->ptr_bits = register_size (regcache->tdesc, 0) * 8;
6275 /* See to_disable_btrace target method. */
6278 linux_low_disable_btrace (struct btrace_target_info *tinfo)
6280 enum btrace_error err;
6282 err = linux_disable_btrace (tinfo);
6283 return (err == BTRACE_ERR_NONE ? 0 : -1);
6286 /* See to_read_btrace target method. */
6289 linux_low_read_btrace (struct btrace_target_info *tinfo, struct buffer *buffer,
6292 struct btrace_data btrace;
6293 struct btrace_block *block;
6294 enum btrace_error err;
6297 btrace_data_init (&btrace);
6299 err = linux_read_btrace (&btrace, tinfo, type);
6300 if (err != BTRACE_ERR_NONE)
6302 if (err == BTRACE_ERR_OVERFLOW)
6303 buffer_grow_str0 (buffer, "E.Overflow.");
6305 buffer_grow_str0 (buffer, "E.Generic Error.");
6307 btrace_data_fini (&btrace);
6311 switch (btrace.format)
6313 case BTRACE_FORMAT_NONE:
6314 buffer_grow_str0 (buffer, "E.No Trace.");
6317 case BTRACE_FORMAT_BTS:
6318 buffer_grow_str (buffer, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
6319 buffer_grow_str (buffer, "<btrace version=\"1.0\">\n");
6322 VEC_iterate (btrace_block_s, btrace.variant.bts.blocks, i, block);
6324 buffer_xml_printf (buffer, "<block begin=\"0x%s\" end=\"0x%s\"/>\n",
6325 paddress (block->begin), paddress (block->end));
6327 buffer_grow_str0 (buffer, "</btrace>\n");
6331 buffer_grow_str0 (buffer, "E.Unknown Trace Format.");
6333 btrace_data_fini (&btrace);
6337 btrace_data_fini (&btrace);
6341 /* See to_btrace_conf target method. */
6344 linux_low_btrace_conf (const struct btrace_target_info *tinfo,
6345 struct buffer *buffer)
6347 const struct btrace_config *conf;
6349 buffer_grow_str (buffer, "<!DOCTYPE btrace-conf SYSTEM \"btrace-conf.dtd\">\n");
6350 buffer_grow_str (buffer, "<btrace-conf version=\"1.0\">\n");
6352 conf = linux_btrace_conf (tinfo);
6355 switch (conf->format)
6357 case BTRACE_FORMAT_NONE:
6360 case BTRACE_FORMAT_BTS:
6361 buffer_xml_printf (buffer, "<bts");
6362 buffer_xml_printf (buffer, " size=\"0x%x\"", conf->bts.size);
6363 buffer_xml_printf (buffer, " />\n");
6368 buffer_grow_str0 (buffer, "</btrace-conf>\n");
6371 #endif /* HAVE_LINUX_BTRACE */
6373 /* See nat/linux-nat.h. */
6376 current_lwp_ptid (void)
6378 return ptid_of (current_thread);
6381 static struct target_ops linux_target_ops = {
6382 linux_create_inferior,
6391 linux_fetch_registers,
6392 linux_store_registers,
6393 linux_prepare_to_access_memory,
6394 linux_done_accessing_memory,
6397 linux_look_up_symbols,
6398 linux_request_interrupt,
6400 linux_supports_z_point_type,
6403 linux_stopped_by_sw_breakpoint,
6404 linux_supports_stopped_by_sw_breakpoint,
6405 linux_stopped_by_hw_breakpoint,
6406 linux_supports_stopped_by_hw_breakpoint,
6407 linux_supports_conditional_breakpoints,
6408 linux_stopped_by_watchpoint,
6409 linux_stopped_data_address,
6410 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
6411 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
6412 && defined(PT_TEXT_END_ADDR)
6417 #ifdef USE_THREAD_DB
6418 thread_db_get_tls_address,
6423 hostio_last_error_from_errno,
6426 linux_supports_non_stop,
6428 linux_start_non_stop,
6429 linux_supports_multi_process,
6430 linux_supports_fork_events,
6431 linux_supports_vfork_events,
6432 #ifdef USE_THREAD_DB
6433 thread_db_handle_monitor_command,
6437 linux_common_core_of_thread,
6439 linux_process_qsupported,
6440 linux_supports_tracepoints,
6443 linux_thread_stopped,
6447 linux_stabilize_threads,
6448 linux_install_fast_tracepoint_jump_pad,
6450 linux_supports_disable_randomization,
6451 linux_get_min_fast_tracepoint_insn_len,
6452 linux_qxfer_libraries_svr4,
6453 linux_supports_agent,
6454 #ifdef HAVE_LINUX_BTRACE
6455 linux_supports_btrace,
6456 linux_low_enable_btrace,
6457 linux_low_disable_btrace,
6458 linux_low_read_btrace,
6459 linux_low_btrace_conf,
6467 linux_supports_range_stepping,
6468 linux_proc_pid_to_exec_file,
6472 linux_init_signals ()
6474 /* FIXME drow/2002-06-09: As above, we should check with LinuxThreads
6475 to find what the cancel signal actually is. */
6476 #ifndef __ANDROID__ /* Bionic doesn't use SIGRTMIN the way glibc does. */
6477 signal (__SIGRTMIN+1, SIG_IGN);
6481 #ifdef HAVE_LINUX_REGSETS
6483 initialize_regsets_info (struct regsets_info *info)
6485 for (info->num_regsets = 0;
6486 info->regsets[info->num_regsets].size >= 0;
6487 info->num_regsets++)
6493 initialize_low (void)
6495 struct sigaction sigchld_action;
6496 memset (&sigchld_action, 0, sizeof (sigchld_action));
6497 set_target_ops (&linux_target_ops);
6498 set_breakpoint_data (the_low_target.breakpoint,
6499 the_low_target.breakpoint_len);
6500 linux_init_signals ();
6501 linux_ptrace_init_warnings ();
6503 sigchld_action.sa_handler = sigchld_handler;
6504 sigemptyset (&sigchld_action.sa_mask);
6505 sigchld_action.sa_flags = SA_RESTART;
6506 sigaction (SIGCHLD, &sigchld_action, NULL);
6508 initialize_low_arch ();
6510 linux_check_ptrace_features ();