Add overloads of for_each_thread/find_thread that filter on pid
[deliverable/binutils-gdb.git] / gdb / gdbserver / linux-low.c
1 /* Low level interface to ptrace, for the remote server for GDB.
2 Copyright (C) 1995-2017 Free Software Foundation, Inc.
3
4 This file is part of GDB.
5
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.
10
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.
15
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/>. */
18
19 #include "server.h"
20 #include "linux-low.h"
21 #include "nat/linux-osdata.h"
22 #include "agent.h"
23 #include "tdesc.h"
24 #include "rsp-low.h"
25 #include "signals-state-save-restore.h"
26 #include "nat/linux-nat.h"
27 #include "nat/linux-waitpid.h"
28 #include "gdb_wait.h"
29 #include "nat/gdb_ptrace.h"
30 #include "nat/linux-ptrace.h"
31 #include "nat/linux-procfs.h"
32 #include "nat/linux-personality.h"
33 #include <signal.h>
34 #include <sys/ioctl.h>
35 #include <fcntl.h>
36 #include <unistd.h>
37 #include <sys/syscall.h>
38 #include <sched.h>
39 #include <ctype.h>
40 #include <pwd.h>
41 #include <sys/types.h>
42 #include <dirent.h>
43 #include <sys/stat.h>
44 #include <sys/vfs.h>
45 #include <sys/uio.h>
46 #include "filestuff.h"
47 #include "tracepoint.h"
48 #include "hostio.h"
49 #include <inttypes.h>
50 #include "common-inferior.h"
51 #include "nat/fork-inferior.h"
52 #include "environ.h"
53 #ifndef ELFMAG0
54 /* Don't include <linux/elf.h> here. If it got included by gdb_proc_service.h
55 then ELFMAG0 will have been defined. If it didn't get included by
56 gdb_proc_service.h then including it will likely introduce a duplicate
57 definition of elf_fpregset_t. */
58 #include <elf.h>
59 #endif
60 #include "nat/linux-namespaces.h"
61
62 #ifndef SPUFS_MAGIC
63 #define SPUFS_MAGIC 0x23c9b64e
64 #endif
65
66 #ifdef HAVE_PERSONALITY
67 # include <sys/personality.h>
68 # if !HAVE_DECL_ADDR_NO_RANDOMIZE
69 # define ADDR_NO_RANDOMIZE 0x0040000
70 # endif
71 #endif
72
73 #ifndef O_LARGEFILE
74 #define O_LARGEFILE 0
75 #endif
76
77 /* Some targets did not define these ptrace constants from the start,
78 so gdbserver defines them locally here. In the future, these may
79 be removed after they are added to asm/ptrace.h. */
80 #if !(defined(PT_TEXT_ADDR) \
81 || defined(PT_DATA_ADDR) \
82 || defined(PT_TEXT_END_ADDR))
83 #if defined(__mcoldfire__)
84 /* These are still undefined in 3.10 kernels. */
85 #define PT_TEXT_ADDR 49*4
86 #define PT_DATA_ADDR 50*4
87 #define PT_TEXT_END_ADDR 51*4
88 /* BFIN already defines these since at least 2.6.32 kernels. */
89 #elif defined(BFIN)
90 #define PT_TEXT_ADDR 220
91 #define PT_TEXT_END_ADDR 224
92 #define PT_DATA_ADDR 228
93 /* These are still undefined in 3.10 kernels. */
94 #elif defined(__TMS320C6X__)
95 #define PT_TEXT_ADDR (0x10000*4)
96 #define PT_DATA_ADDR (0x10004*4)
97 #define PT_TEXT_END_ADDR (0x10008*4)
98 #endif
99 #endif
100
101 #ifdef HAVE_LINUX_BTRACE
102 # include "nat/linux-btrace.h"
103 # include "btrace-common.h"
104 #endif
105
106 #ifndef HAVE_ELF32_AUXV_T
107 /* Copied from glibc's elf.h. */
108 typedef struct
109 {
110 uint32_t a_type; /* Entry type */
111 union
112 {
113 uint32_t a_val; /* Integer value */
114 /* We use to have pointer elements added here. We cannot do that,
115 though, since it does not work when using 32-bit definitions
116 on 64-bit platforms and vice versa. */
117 } a_un;
118 } Elf32_auxv_t;
119 #endif
120
121 #ifndef HAVE_ELF64_AUXV_T
122 /* Copied from glibc's elf.h. */
123 typedef struct
124 {
125 uint64_t a_type; /* Entry type */
126 union
127 {
128 uint64_t a_val; /* Integer value */
129 /* We use to have pointer elements added here. We cannot do that,
130 though, since it does not work when using 32-bit definitions
131 on 64-bit platforms and vice versa. */
132 } a_un;
133 } Elf64_auxv_t;
134 #endif
135
136 /* Does the current host support PTRACE_GETREGSET? */
137 int have_ptrace_getregset = -1;
138
139 /* LWP accessors. */
140
141 /* See nat/linux-nat.h. */
142
143 ptid_t
144 ptid_of_lwp (struct lwp_info *lwp)
145 {
146 return ptid_of (get_lwp_thread (lwp));
147 }
148
149 /* See nat/linux-nat.h. */
150
151 void
152 lwp_set_arch_private_info (struct lwp_info *lwp,
153 struct arch_lwp_info *info)
154 {
155 lwp->arch_private = info;
156 }
157
158 /* See nat/linux-nat.h. */
159
160 struct arch_lwp_info *
161 lwp_arch_private_info (struct lwp_info *lwp)
162 {
163 return lwp->arch_private;
164 }
165
166 /* See nat/linux-nat.h. */
167
168 int
169 lwp_is_stopped (struct lwp_info *lwp)
170 {
171 return lwp->stopped;
172 }
173
174 /* See nat/linux-nat.h. */
175
176 enum target_stop_reason
177 lwp_stop_reason (struct lwp_info *lwp)
178 {
179 return lwp->stop_reason;
180 }
181
182 /* See nat/linux-nat.h. */
183
184 int
185 lwp_is_stepping (struct lwp_info *lwp)
186 {
187 return lwp->stepping;
188 }
189
190 /* A list of all unknown processes which receive stop signals. Some
191 other process will presumably claim each of these as forked
192 children momentarily. */
193
194 struct simple_pid_list
195 {
196 /* The process ID. */
197 int pid;
198
199 /* The status as reported by waitpid. */
200 int status;
201
202 /* Next in chain. */
203 struct simple_pid_list *next;
204 };
205 struct simple_pid_list *stopped_pids;
206
207 /* Trivial list manipulation functions to keep track of a list of new
208 stopped processes. */
209
210 static void
211 add_to_pid_list (struct simple_pid_list **listp, int pid, int status)
212 {
213 struct simple_pid_list *new_pid = XNEW (struct simple_pid_list);
214
215 new_pid->pid = pid;
216 new_pid->status = status;
217 new_pid->next = *listp;
218 *listp = new_pid;
219 }
220
221 static int
222 pull_pid_from_list (struct simple_pid_list **listp, int pid, int *statusp)
223 {
224 struct simple_pid_list **p;
225
226 for (p = listp; *p != NULL; p = &(*p)->next)
227 if ((*p)->pid == pid)
228 {
229 struct simple_pid_list *next = (*p)->next;
230
231 *statusp = (*p)->status;
232 xfree (*p);
233 *p = next;
234 return 1;
235 }
236 return 0;
237 }
238
239 enum stopping_threads_kind
240 {
241 /* Not stopping threads presently. */
242 NOT_STOPPING_THREADS,
243
244 /* Stopping threads. */
245 STOPPING_THREADS,
246
247 /* Stopping and suspending threads. */
248 STOPPING_AND_SUSPENDING_THREADS
249 };
250
251 /* This is set while stop_all_lwps is in effect. */
252 enum stopping_threads_kind stopping_threads = NOT_STOPPING_THREADS;
253
254 /* FIXME make into a target method? */
255 int using_threads = 1;
256
257 /* True if we're presently stabilizing threads (moving them out of
258 jump pads). */
259 static int stabilizing_threads;
260
261 static void linux_resume_one_lwp (struct lwp_info *lwp,
262 int step, int signal, siginfo_t *info);
263 static void linux_resume (struct thread_resume *resume_info, size_t n);
264 static void stop_all_lwps (int suspend, struct lwp_info *except);
265 static void unstop_all_lwps (int unsuspend, struct lwp_info *except);
266 static void unsuspend_all_lwps (struct lwp_info *except);
267 static int linux_wait_for_event_filtered (ptid_t wait_ptid, ptid_t filter_ptid,
268 int *wstat, int options);
269 static int linux_wait_for_event (ptid_t ptid, int *wstat, int options);
270 static struct lwp_info *add_lwp (ptid_t ptid);
271 static void linux_mourn (struct process_info *process);
272 static int linux_stopped_by_watchpoint (void);
273 static void mark_lwp_dead (struct lwp_info *lwp, int wstat);
274 static int lwp_is_marked_dead (struct lwp_info *lwp);
275 static void proceed_all_lwps (void);
276 static int finish_step_over (struct lwp_info *lwp);
277 static int kill_lwp (unsigned long lwpid, int signo);
278 static void enqueue_pending_signal (struct lwp_info *lwp, int signal, siginfo_t *info);
279 static void complete_ongoing_step_over (void);
280 static int linux_low_ptrace_options (int attached);
281 static int check_ptrace_stopped_lwp_gone (struct lwp_info *lp);
282 static int proceed_one_lwp (thread_info *thread, void *except);
283
284 /* When the event-loop is doing a step-over, this points at the thread
285 being stepped. */
286 ptid_t step_over_bkpt;
287
288 /* True if the low target can hardware single-step. */
289
290 static int
291 can_hardware_single_step (void)
292 {
293 if (the_low_target.supports_hardware_single_step != NULL)
294 return the_low_target.supports_hardware_single_step ();
295 else
296 return 0;
297 }
298
299 /* True if the low target can software single-step. Such targets
300 implement the GET_NEXT_PCS callback. */
301
302 static int
303 can_software_single_step (void)
304 {
305 return (the_low_target.get_next_pcs != NULL);
306 }
307
308 /* True if the low target supports memory breakpoints. If so, we'll
309 have a GET_PC implementation. */
310
311 static int
312 supports_breakpoints (void)
313 {
314 return (the_low_target.get_pc != NULL);
315 }
316
317 /* Returns true if this target can support fast tracepoints. This
318 does not mean that the in-process agent has been loaded in the
319 inferior. */
320
321 static int
322 supports_fast_tracepoints (void)
323 {
324 return the_low_target.install_fast_tracepoint_jump_pad != NULL;
325 }
326
327 /* True if LWP is stopped in its stepping range. */
328
329 static int
330 lwp_in_step_range (struct lwp_info *lwp)
331 {
332 CORE_ADDR pc = lwp->stop_pc;
333
334 return (pc >= lwp->step_range_start && pc < lwp->step_range_end);
335 }
336
337 struct pending_signals
338 {
339 int signal;
340 siginfo_t info;
341 struct pending_signals *prev;
342 };
343
344 /* The read/write ends of the pipe registered as waitable file in the
345 event loop. */
346 static int linux_event_pipe[2] = { -1, -1 };
347
348 /* True if we're currently in async mode. */
349 #define target_is_async_p() (linux_event_pipe[0] != -1)
350
351 static void send_sigstop (struct lwp_info *lwp);
352 static void wait_for_sigstop (void);
353
354 /* Return non-zero if HEADER is a 64-bit ELF file. */
355
356 static int
357 elf_64_header_p (const Elf64_Ehdr *header, unsigned int *machine)
358 {
359 if (header->e_ident[EI_MAG0] == ELFMAG0
360 && header->e_ident[EI_MAG1] == ELFMAG1
361 && header->e_ident[EI_MAG2] == ELFMAG2
362 && header->e_ident[EI_MAG3] == ELFMAG3)
363 {
364 *machine = header->e_machine;
365 return header->e_ident[EI_CLASS] == ELFCLASS64;
366
367 }
368 *machine = EM_NONE;
369 return -1;
370 }
371
372 /* Return non-zero if FILE is a 64-bit ELF file,
373 zero if the file is not a 64-bit ELF file,
374 and -1 if the file is not accessible or doesn't exist. */
375
376 static int
377 elf_64_file_p (const char *file, unsigned int *machine)
378 {
379 Elf64_Ehdr header;
380 int fd;
381
382 fd = open (file, O_RDONLY);
383 if (fd < 0)
384 return -1;
385
386 if (read (fd, &header, sizeof (header)) != sizeof (header))
387 {
388 close (fd);
389 return 0;
390 }
391 close (fd);
392
393 return elf_64_header_p (&header, machine);
394 }
395
396 /* Accepts an integer PID; Returns true if the executable PID is
397 running is a 64-bit ELF file.. */
398
399 int
400 linux_pid_exe_is_elf_64_file (int pid, unsigned int *machine)
401 {
402 char file[PATH_MAX];
403
404 sprintf (file, "/proc/%d/exe", pid);
405 return elf_64_file_p (file, machine);
406 }
407
408 static void
409 delete_lwp (struct lwp_info *lwp)
410 {
411 struct thread_info *thr = get_lwp_thread (lwp);
412
413 if (debug_threads)
414 debug_printf ("deleting %ld\n", lwpid_of (thr));
415
416 remove_thread (thr);
417
418 if (the_low_target.delete_thread != NULL)
419 the_low_target.delete_thread (lwp->arch_private);
420 else
421 gdb_assert (lwp->arch_private == NULL);
422
423 free (lwp);
424 }
425
426 /* Add a process to the common process list, and set its private
427 data. */
428
429 static struct process_info *
430 linux_add_process (int pid, int attached)
431 {
432 struct process_info *proc;
433
434 proc = add_process (pid, attached);
435 proc->priv = XCNEW (struct process_info_private);
436
437 if (the_low_target.new_process != NULL)
438 proc->priv->arch_private = the_low_target.new_process ();
439
440 return proc;
441 }
442
443 static CORE_ADDR get_pc (struct lwp_info *lwp);
444
445 /* Call the target arch_setup function on the current thread. */
446
447 static void
448 linux_arch_setup (void)
449 {
450 the_low_target.arch_setup ();
451 }
452
453 /* Call the target arch_setup function on THREAD. */
454
455 static void
456 linux_arch_setup_thread (struct thread_info *thread)
457 {
458 struct thread_info *saved_thread;
459
460 saved_thread = current_thread;
461 current_thread = thread;
462
463 linux_arch_setup ();
464
465 current_thread = saved_thread;
466 }
467
468 /* Handle a GNU/Linux extended wait response. If we see a clone,
469 fork, or vfork event, we need to add the new LWP to our list
470 (and return 0 so as not to report the trap to higher layers).
471 If we see an exec event, we will modify ORIG_EVENT_LWP to point
472 to a new LWP representing the new program. */
473
474 static int
475 handle_extended_wait (struct lwp_info **orig_event_lwp, int wstat)
476 {
477 struct lwp_info *event_lwp = *orig_event_lwp;
478 int event = linux_ptrace_get_extended_event (wstat);
479 struct thread_info *event_thr = get_lwp_thread (event_lwp);
480 struct lwp_info *new_lwp;
481
482 gdb_assert (event_lwp->waitstatus.kind == TARGET_WAITKIND_IGNORE);
483
484 /* All extended events we currently use are mid-syscall. Only
485 PTRACE_EVENT_STOP is delivered more like a signal-stop, but
486 you have to be using PTRACE_SEIZE to get that. */
487 event_lwp->syscall_state = TARGET_WAITKIND_SYSCALL_ENTRY;
488
489 if ((event == PTRACE_EVENT_FORK) || (event == PTRACE_EVENT_VFORK)
490 || (event == PTRACE_EVENT_CLONE))
491 {
492 ptid_t ptid;
493 unsigned long new_pid;
494 int ret, status;
495
496 /* Get the pid of the new lwp. */
497 ptrace (PTRACE_GETEVENTMSG, lwpid_of (event_thr), (PTRACE_TYPE_ARG3) 0,
498 &new_pid);
499
500 /* If we haven't already seen the new PID stop, wait for it now. */
501 if (!pull_pid_from_list (&stopped_pids, new_pid, &status))
502 {
503 /* The new child has a pending SIGSTOP. We can't affect it until it
504 hits the SIGSTOP, but we're already attached. */
505
506 ret = my_waitpid (new_pid, &status, __WALL);
507
508 if (ret == -1)
509 perror_with_name ("waiting for new child");
510 else if (ret != new_pid)
511 warning ("wait returned unexpected PID %d", ret);
512 else if (!WIFSTOPPED (status))
513 warning ("wait returned unexpected status 0x%x", status);
514 }
515
516 if (event == PTRACE_EVENT_FORK || event == PTRACE_EVENT_VFORK)
517 {
518 struct process_info *parent_proc;
519 struct process_info *child_proc;
520 struct lwp_info *child_lwp;
521 struct thread_info *child_thr;
522 struct target_desc *tdesc;
523
524 ptid = ptid_build (new_pid, new_pid, 0);
525
526 if (debug_threads)
527 {
528 debug_printf ("HEW: Got fork event from LWP %ld, "
529 "new child is %d\n",
530 ptid_get_lwp (ptid_of (event_thr)),
531 ptid_get_pid (ptid));
532 }
533
534 /* Add the new process to the tables and clone the breakpoint
535 lists of the parent. We need to do this even if the new process
536 will be detached, since we will need the process object and the
537 breakpoints to remove any breakpoints from memory when we
538 detach, and the client side will access registers. */
539 child_proc = linux_add_process (new_pid, 0);
540 gdb_assert (child_proc != NULL);
541 child_lwp = add_lwp (ptid);
542 gdb_assert (child_lwp != NULL);
543 child_lwp->stopped = 1;
544 child_lwp->must_set_ptrace_flags = 1;
545 child_lwp->status_pending_p = 0;
546 child_thr = get_lwp_thread (child_lwp);
547 child_thr->last_resume_kind = resume_stop;
548 child_thr->last_status.kind = TARGET_WAITKIND_STOPPED;
549
550 /* If we're suspending all threads, leave this one suspended
551 too. If the fork/clone parent is stepping over a breakpoint,
552 all other threads have been suspended already. Leave the
553 child suspended too. */
554 if (stopping_threads == STOPPING_AND_SUSPENDING_THREADS
555 || event_lwp->bp_reinsert != 0)
556 {
557 if (debug_threads)
558 debug_printf ("HEW: leaving child suspended\n");
559 child_lwp->suspended = 1;
560 }
561
562 parent_proc = get_thread_process (event_thr);
563 child_proc->attached = parent_proc->attached;
564
565 if (event_lwp->bp_reinsert != 0
566 && can_software_single_step ()
567 && event == PTRACE_EVENT_VFORK)
568 {
569 /* If we leave single-step breakpoints there, child will
570 hit it, so uninsert single-step breakpoints from parent
571 (and child). Once vfork child is done, reinsert
572 them back to parent. */
573 uninsert_single_step_breakpoints (event_thr);
574 }
575
576 clone_all_breakpoints (child_thr, event_thr);
577
578 tdesc = allocate_target_description ();
579 copy_target_description (tdesc, parent_proc->tdesc);
580 child_proc->tdesc = tdesc;
581
582 /* Clone arch-specific process data. */
583 if (the_low_target.new_fork != NULL)
584 the_low_target.new_fork (parent_proc, child_proc);
585
586 /* Save fork info in the parent thread. */
587 if (event == PTRACE_EVENT_FORK)
588 event_lwp->waitstatus.kind = TARGET_WAITKIND_FORKED;
589 else if (event == PTRACE_EVENT_VFORK)
590 event_lwp->waitstatus.kind = TARGET_WAITKIND_VFORKED;
591
592 event_lwp->waitstatus.value.related_pid = ptid;
593
594 /* The status_pending field contains bits denoting the
595 extended event, so when the pending event is handled,
596 the handler will look at lwp->waitstatus. */
597 event_lwp->status_pending_p = 1;
598 event_lwp->status_pending = wstat;
599
600 /* Link the threads until the parent event is passed on to
601 higher layers. */
602 event_lwp->fork_relative = child_lwp;
603 child_lwp->fork_relative = event_lwp;
604
605 /* If the parent thread is doing step-over with single-step
606 breakpoints, the list of single-step breakpoints are cloned
607 from the parent's. Remove them from the child process.
608 In case of vfork, we'll reinsert them back once vforked
609 child is done. */
610 if (event_lwp->bp_reinsert != 0
611 && can_software_single_step ())
612 {
613 /* The child process is forked and stopped, so it is safe
614 to access its memory without stopping all other threads
615 from other processes. */
616 delete_single_step_breakpoints (child_thr);
617
618 gdb_assert (has_single_step_breakpoints (event_thr));
619 gdb_assert (!has_single_step_breakpoints (child_thr));
620 }
621
622 /* Report the event. */
623 return 0;
624 }
625
626 if (debug_threads)
627 debug_printf ("HEW: Got clone event "
628 "from LWP %ld, new child is LWP %ld\n",
629 lwpid_of (event_thr), new_pid);
630
631 ptid = ptid_build (pid_of (event_thr), new_pid, 0);
632 new_lwp = add_lwp (ptid);
633
634 /* Either we're going to immediately resume the new thread
635 or leave it stopped. linux_resume_one_lwp is a nop if it
636 thinks the thread is currently running, so set this first
637 before calling linux_resume_one_lwp. */
638 new_lwp->stopped = 1;
639
640 /* If we're suspending all threads, leave this one suspended
641 too. If the fork/clone parent is stepping over a breakpoint,
642 all other threads have been suspended already. Leave the
643 child suspended too. */
644 if (stopping_threads == STOPPING_AND_SUSPENDING_THREADS
645 || event_lwp->bp_reinsert != 0)
646 new_lwp->suspended = 1;
647
648 /* Normally we will get the pending SIGSTOP. But in some cases
649 we might get another signal delivered to the group first.
650 If we do get another signal, be sure not to lose it. */
651 if (WSTOPSIG (status) != SIGSTOP)
652 {
653 new_lwp->stop_expected = 1;
654 new_lwp->status_pending_p = 1;
655 new_lwp->status_pending = status;
656 }
657 else if (report_thread_events)
658 {
659 new_lwp->waitstatus.kind = TARGET_WAITKIND_THREAD_CREATED;
660 new_lwp->status_pending_p = 1;
661 new_lwp->status_pending = status;
662 }
663
664 thread_db_notice_clone (event_thr, ptid);
665
666 /* Don't report the event. */
667 return 1;
668 }
669 else if (event == PTRACE_EVENT_VFORK_DONE)
670 {
671 event_lwp->waitstatus.kind = TARGET_WAITKIND_VFORK_DONE;
672
673 if (event_lwp->bp_reinsert != 0 && can_software_single_step ())
674 {
675 reinsert_single_step_breakpoints (event_thr);
676
677 gdb_assert (has_single_step_breakpoints (event_thr));
678 }
679
680 /* Report the event. */
681 return 0;
682 }
683 else if (event == PTRACE_EVENT_EXEC && report_exec_events)
684 {
685 struct process_info *proc;
686 VEC (int) *syscalls_to_catch;
687 ptid_t event_ptid;
688 pid_t event_pid;
689
690 if (debug_threads)
691 {
692 debug_printf ("HEW: Got exec event from LWP %ld\n",
693 lwpid_of (event_thr));
694 }
695
696 /* Get the event ptid. */
697 event_ptid = ptid_of (event_thr);
698 event_pid = ptid_get_pid (event_ptid);
699
700 /* Save the syscall list from the execing process. */
701 proc = get_thread_process (event_thr);
702 syscalls_to_catch = proc->syscalls_to_catch;
703 proc->syscalls_to_catch = NULL;
704
705 /* Delete the execing process and all its threads. */
706 linux_mourn (proc);
707 current_thread = NULL;
708
709 /* Create a new process/lwp/thread. */
710 proc = linux_add_process (event_pid, 0);
711 event_lwp = add_lwp (event_ptid);
712 event_thr = get_lwp_thread (event_lwp);
713 gdb_assert (current_thread == event_thr);
714 linux_arch_setup_thread (event_thr);
715
716 /* Set the event status. */
717 event_lwp->waitstatus.kind = TARGET_WAITKIND_EXECD;
718 event_lwp->waitstatus.value.execd_pathname
719 = xstrdup (linux_proc_pid_to_exec_file (lwpid_of (event_thr)));
720
721 /* Mark the exec status as pending. */
722 event_lwp->stopped = 1;
723 event_lwp->status_pending_p = 1;
724 event_lwp->status_pending = wstat;
725 event_thr->last_resume_kind = resume_continue;
726 event_thr->last_status.kind = TARGET_WAITKIND_IGNORE;
727
728 /* Update syscall state in the new lwp, effectively mid-syscall too. */
729 event_lwp->syscall_state = TARGET_WAITKIND_SYSCALL_ENTRY;
730
731 /* Restore the list to catch. Don't rely on the client, which is free
732 to avoid sending a new list when the architecture doesn't change.
733 Also, for ANY_SYSCALL, the architecture doesn't really matter. */
734 proc->syscalls_to_catch = syscalls_to_catch;
735
736 /* Report the event. */
737 *orig_event_lwp = event_lwp;
738 return 0;
739 }
740
741 internal_error (__FILE__, __LINE__, _("unknown ptrace event %d"), event);
742 }
743
744 /* Return the PC as read from the regcache of LWP, without any
745 adjustment. */
746
747 static CORE_ADDR
748 get_pc (struct lwp_info *lwp)
749 {
750 struct thread_info *saved_thread;
751 struct regcache *regcache;
752 CORE_ADDR pc;
753
754 if (the_low_target.get_pc == NULL)
755 return 0;
756
757 saved_thread = current_thread;
758 current_thread = get_lwp_thread (lwp);
759
760 regcache = get_thread_regcache (current_thread, 1);
761 pc = (*the_low_target.get_pc) (regcache);
762
763 if (debug_threads)
764 debug_printf ("pc is 0x%lx\n", (long) pc);
765
766 current_thread = saved_thread;
767 return pc;
768 }
769
770 /* This function should only be called if LWP got a SYSCALL_SIGTRAP.
771 Fill *SYSNO with the syscall nr trapped. */
772
773 static void
774 get_syscall_trapinfo (struct lwp_info *lwp, int *sysno)
775 {
776 struct thread_info *saved_thread;
777 struct regcache *regcache;
778
779 if (the_low_target.get_syscall_trapinfo == NULL)
780 {
781 /* If we cannot get the syscall trapinfo, report an unknown
782 system call number. */
783 *sysno = UNKNOWN_SYSCALL;
784 return;
785 }
786
787 saved_thread = current_thread;
788 current_thread = get_lwp_thread (lwp);
789
790 regcache = get_thread_regcache (current_thread, 1);
791 (*the_low_target.get_syscall_trapinfo) (regcache, sysno);
792
793 if (debug_threads)
794 debug_printf ("get_syscall_trapinfo sysno %d\n", *sysno);
795
796 current_thread = saved_thread;
797 }
798
799 static int check_stopped_by_watchpoint (struct lwp_info *child);
800
801 /* Called when the LWP stopped for a signal/trap. If it stopped for a
802 trap check what caused it (breakpoint, watchpoint, trace, etc.),
803 and save the result in the LWP's stop_reason field. If it stopped
804 for a breakpoint, decrement the PC if necessary on the lwp's
805 architecture. Returns true if we now have the LWP's stop PC. */
806
807 static int
808 save_stop_reason (struct lwp_info *lwp)
809 {
810 CORE_ADDR pc;
811 CORE_ADDR sw_breakpoint_pc;
812 struct thread_info *saved_thread;
813 #if USE_SIGTRAP_SIGINFO
814 siginfo_t siginfo;
815 #endif
816
817 if (the_low_target.get_pc == NULL)
818 return 0;
819
820 pc = get_pc (lwp);
821 sw_breakpoint_pc = pc - the_low_target.decr_pc_after_break;
822
823 /* breakpoint_at reads from the current thread. */
824 saved_thread = current_thread;
825 current_thread = get_lwp_thread (lwp);
826
827 #if USE_SIGTRAP_SIGINFO
828 if (ptrace (PTRACE_GETSIGINFO, lwpid_of (current_thread),
829 (PTRACE_TYPE_ARG3) 0, &siginfo) == 0)
830 {
831 if (siginfo.si_signo == SIGTRAP)
832 {
833 if (GDB_ARCH_IS_TRAP_BRKPT (siginfo.si_code)
834 && GDB_ARCH_IS_TRAP_HWBKPT (siginfo.si_code))
835 {
836 /* The si_code is ambiguous on this arch -- check debug
837 registers. */
838 if (!check_stopped_by_watchpoint (lwp))
839 lwp->stop_reason = TARGET_STOPPED_BY_SW_BREAKPOINT;
840 }
841 else if (GDB_ARCH_IS_TRAP_BRKPT (siginfo.si_code))
842 {
843 /* If we determine the LWP stopped for a SW breakpoint,
844 trust it. Particularly don't check watchpoint
845 registers, because at least on s390, we'd find
846 stopped-by-watchpoint as long as there's a watchpoint
847 set. */
848 lwp->stop_reason = TARGET_STOPPED_BY_SW_BREAKPOINT;
849 }
850 else if (GDB_ARCH_IS_TRAP_HWBKPT (siginfo.si_code))
851 {
852 /* This can indicate either a hardware breakpoint or
853 hardware watchpoint. Check debug registers. */
854 if (!check_stopped_by_watchpoint (lwp))
855 lwp->stop_reason = TARGET_STOPPED_BY_HW_BREAKPOINT;
856 }
857 else if (siginfo.si_code == TRAP_TRACE)
858 {
859 /* We may have single stepped an instruction that
860 triggered a watchpoint. In that case, on some
861 architectures (such as x86), instead of TRAP_HWBKPT,
862 si_code indicates TRAP_TRACE, and we need to check
863 the debug registers separately. */
864 if (!check_stopped_by_watchpoint (lwp))
865 lwp->stop_reason = TARGET_STOPPED_BY_SINGLE_STEP;
866 }
867 }
868 }
869 #else
870 /* We may have just stepped a breakpoint instruction. E.g., in
871 non-stop mode, GDB first tells the thread A to step a range, and
872 then the user inserts a breakpoint inside the range. In that
873 case we need to report the breakpoint PC. */
874 if ((!lwp->stepping || lwp->stop_pc == sw_breakpoint_pc)
875 && (*the_low_target.breakpoint_at) (sw_breakpoint_pc))
876 lwp->stop_reason = TARGET_STOPPED_BY_SW_BREAKPOINT;
877
878 if (hardware_breakpoint_inserted_here (pc))
879 lwp->stop_reason = TARGET_STOPPED_BY_HW_BREAKPOINT;
880
881 if (lwp->stop_reason == TARGET_STOPPED_BY_NO_REASON)
882 check_stopped_by_watchpoint (lwp);
883 #endif
884
885 if (lwp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT)
886 {
887 if (debug_threads)
888 {
889 struct thread_info *thr = get_lwp_thread (lwp);
890
891 debug_printf ("CSBB: %s stopped by software breakpoint\n",
892 target_pid_to_str (ptid_of (thr)));
893 }
894
895 /* Back up the PC if necessary. */
896 if (pc != sw_breakpoint_pc)
897 {
898 struct regcache *regcache
899 = get_thread_regcache (current_thread, 1);
900 (*the_low_target.set_pc) (regcache, sw_breakpoint_pc);
901 }
902
903 /* Update this so we record the correct stop PC below. */
904 pc = sw_breakpoint_pc;
905 }
906 else if (lwp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT)
907 {
908 if (debug_threads)
909 {
910 struct thread_info *thr = get_lwp_thread (lwp);
911
912 debug_printf ("CSBB: %s stopped by hardware breakpoint\n",
913 target_pid_to_str (ptid_of (thr)));
914 }
915 }
916 else if (lwp->stop_reason == TARGET_STOPPED_BY_WATCHPOINT)
917 {
918 if (debug_threads)
919 {
920 struct thread_info *thr = get_lwp_thread (lwp);
921
922 debug_printf ("CSBB: %s stopped by hardware watchpoint\n",
923 target_pid_to_str (ptid_of (thr)));
924 }
925 }
926 else if (lwp->stop_reason == TARGET_STOPPED_BY_SINGLE_STEP)
927 {
928 if (debug_threads)
929 {
930 struct thread_info *thr = get_lwp_thread (lwp);
931
932 debug_printf ("CSBB: %s stopped by trace\n",
933 target_pid_to_str (ptid_of (thr)));
934 }
935 }
936
937 lwp->stop_pc = pc;
938 current_thread = saved_thread;
939 return 1;
940 }
941
942 static struct lwp_info *
943 add_lwp (ptid_t ptid)
944 {
945 struct lwp_info *lwp;
946
947 lwp = XCNEW (struct lwp_info);
948
949 lwp->waitstatus.kind = TARGET_WAITKIND_IGNORE;
950
951 if (the_low_target.new_thread != NULL)
952 the_low_target.new_thread (lwp);
953
954 lwp->thread = add_thread (ptid, lwp);
955
956 return lwp;
957 }
958
959 /* Callback to be used when calling fork_inferior, responsible for
960 actually initiating the tracing of the inferior. */
961
962 static void
963 linux_ptrace_fun ()
964 {
965 if (ptrace (PTRACE_TRACEME, 0, (PTRACE_TYPE_ARG3) 0,
966 (PTRACE_TYPE_ARG4) 0) < 0)
967 trace_start_error_with_name ("ptrace");
968
969 if (setpgid (0, 0) < 0)
970 trace_start_error_with_name ("setpgid");
971
972 /* If GDBserver is connected to gdb via stdio, redirect the inferior's
973 stdout to stderr so that inferior i/o doesn't corrupt the connection.
974 Also, redirect stdin to /dev/null. */
975 if (remote_connection_is_stdio ())
976 {
977 if (close (0) < 0)
978 trace_start_error_with_name ("close");
979 if (open ("/dev/null", O_RDONLY) < 0)
980 trace_start_error_with_name ("open");
981 if (dup2 (2, 1) < 0)
982 trace_start_error_with_name ("dup2");
983 if (write (2, "stdin/stdout redirected\n",
984 sizeof ("stdin/stdout redirected\n") - 1) < 0)
985 {
986 /* Errors ignored. */;
987 }
988 }
989 }
990
991 /* Start an inferior process and returns its pid.
992 PROGRAM is the name of the program to be started, and PROGRAM_ARGS
993 are its arguments. */
994
995 static int
996 linux_create_inferior (const char *program,
997 const std::vector<char *> &program_args)
998 {
999 struct lwp_info *new_lwp;
1000 int pid;
1001 ptid_t ptid;
1002 struct cleanup *restore_personality
1003 = maybe_disable_address_space_randomization (disable_randomization);
1004 std::string str_program_args = stringify_argv (program_args);
1005
1006 pid = fork_inferior (program,
1007 str_program_args.c_str (),
1008 get_environ ()->envp (), linux_ptrace_fun,
1009 NULL, NULL, NULL, NULL);
1010
1011 do_cleanups (restore_personality);
1012
1013 linux_add_process (pid, 0);
1014
1015 ptid = ptid_build (pid, pid, 0);
1016 new_lwp = add_lwp (ptid);
1017 new_lwp->must_set_ptrace_flags = 1;
1018
1019 post_fork_inferior (pid, program);
1020
1021 return pid;
1022 }
1023
1024 /* Implement the post_create_inferior target_ops method. */
1025
1026 static void
1027 linux_post_create_inferior (void)
1028 {
1029 struct lwp_info *lwp = get_thread_lwp (current_thread);
1030
1031 linux_arch_setup ();
1032
1033 if (lwp->must_set_ptrace_flags)
1034 {
1035 struct process_info *proc = current_process ();
1036 int options = linux_low_ptrace_options (proc->attached);
1037
1038 linux_enable_event_reporting (lwpid_of (current_thread), options);
1039 lwp->must_set_ptrace_flags = 0;
1040 }
1041 }
1042
1043 /* Attach to an inferior process. Returns 0 on success, ERRNO on
1044 error. */
1045
1046 int
1047 linux_attach_lwp (ptid_t ptid)
1048 {
1049 struct lwp_info *new_lwp;
1050 int lwpid = ptid_get_lwp (ptid);
1051
1052 if (ptrace (PTRACE_ATTACH, lwpid, (PTRACE_TYPE_ARG3) 0, (PTRACE_TYPE_ARG4) 0)
1053 != 0)
1054 return errno;
1055
1056 new_lwp = add_lwp (ptid);
1057
1058 /* We need to wait for SIGSTOP before being able to make the next
1059 ptrace call on this LWP. */
1060 new_lwp->must_set_ptrace_flags = 1;
1061
1062 if (linux_proc_pid_is_stopped (lwpid))
1063 {
1064 if (debug_threads)
1065 debug_printf ("Attached to a stopped process\n");
1066
1067 /* The process is definitely stopped. It is in a job control
1068 stop, unless the kernel predates the TASK_STOPPED /
1069 TASK_TRACED distinction, in which case it might be in a
1070 ptrace stop. Make sure it is in a ptrace stop; from there we
1071 can kill it, signal it, et cetera.
1072
1073 First make sure there is a pending SIGSTOP. Since we are
1074 already attached, the process can not transition from stopped
1075 to running without a PTRACE_CONT; so we know this signal will
1076 go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
1077 probably already in the queue (unless this kernel is old
1078 enough to use TASK_STOPPED for ptrace stops); but since
1079 SIGSTOP is not an RT signal, it can only be queued once. */
1080 kill_lwp (lwpid, SIGSTOP);
1081
1082 /* Finally, resume the stopped process. This will deliver the
1083 SIGSTOP (or a higher priority signal, just like normal
1084 PTRACE_ATTACH), which we'll catch later on. */
1085 ptrace (PTRACE_CONT, lwpid, (PTRACE_TYPE_ARG3) 0, (PTRACE_TYPE_ARG4) 0);
1086 }
1087
1088 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
1089 brings it to a halt.
1090
1091 There are several cases to consider here:
1092
1093 1) gdbserver has already attached to the process and is being notified
1094 of a new thread that is being created.
1095 In this case we should ignore that SIGSTOP and resume the
1096 process. This is handled below by setting stop_expected = 1,
1097 and the fact that add_thread sets last_resume_kind ==
1098 resume_continue.
1099
1100 2) This is the first thread (the process thread), and we're attaching
1101 to it via attach_inferior.
1102 In this case we want the process thread to stop.
1103 This is handled by having linux_attach set last_resume_kind ==
1104 resume_stop after we return.
1105
1106 If the pid we are attaching to is also the tgid, we attach to and
1107 stop all the existing threads. Otherwise, we attach to pid and
1108 ignore any other threads in the same group as this pid.
1109
1110 3) GDB is connecting to gdbserver and is requesting an enumeration of all
1111 existing threads.
1112 In this case we want the thread to stop.
1113 FIXME: This case is currently not properly handled.
1114 We should wait for the SIGSTOP but don't. Things work apparently
1115 because enough time passes between when we ptrace (ATTACH) and when
1116 gdb makes the next ptrace call on the thread.
1117
1118 On the other hand, if we are currently trying to stop all threads, we
1119 should treat the new thread as if we had sent it a SIGSTOP. This works
1120 because we are guaranteed that the add_lwp call above added us to the
1121 end of the list, and so the new thread has not yet reached
1122 wait_for_sigstop (but will). */
1123 new_lwp->stop_expected = 1;
1124
1125 return 0;
1126 }
1127
1128 /* Callback for linux_proc_attach_tgid_threads. Attach to PTID if not
1129 already attached. Returns true if a new LWP is found, false
1130 otherwise. */
1131
1132 static int
1133 attach_proc_task_lwp_callback (ptid_t ptid)
1134 {
1135 /* Is this a new thread? */
1136 if (find_thread_ptid (ptid) == NULL)
1137 {
1138 int lwpid = ptid_get_lwp (ptid);
1139 int err;
1140
1141 if (debug_threads)
1142 debug_printf ("Found new lwp %d\n", lwpid);
1143
1144 err = linux_attach_lwp (ptid);
1145
1146 /* Be quiet if we simply raced with the thread exiting. EPERM
1147 is returned if the thread's task still exists, and is marked
1148 as exited or zombie, as well as other conditions, so in that
1149 case, confirm the status in /proc/PID/status. */
1150 if (err == ESRCH
1151 || (err == EPERM && linux_proc_pid_is_gone (lwpid)))
1152 {
1153 if (debug_threads)
1154 {
1155 debug_printf ("Cannot attach to lwp %d: "
1156 "thread is gone (%d: %s)\n",
1157 lwpid, err, strerror (err));
1158 }
1159 }
1160 else if (err != 0)
1161 {
1162 warning (_("Cannot attach to lwp %d: %s"),
1163 lwpid,
1164 linux_ptrace_attach_fail_reason_string (ptid, err));
1165 }
1166
1167 return 1;
1168 }
1169 return 0;
1170 }
1171
1172 static void async_file_mark (void);
1173
1174 /* Attach to PID. If PID is the tgid, attach to it and all
1175 of its threads. */
1176
1177 static int
1178 linux_attach (unsigned long pid)
1179 {
1180 struct process_info *proc;
1181 struct thread_info *initial_thread;
1182 ptid_t ptid = ptid_build (pid, pid, 0);
1183 int err;
1184
1185 /* Attach to PID. We will check for other threads
1186 soon. */
1187 err = linux_attach_lwp (ptid);
1188 if (err != 0)
1189 error ("Cannot attach to process %ld: %s",
1190 pid, linux_ptrace_attach_fail_reason_string (ptid, err));
1191
1192 proc = linux_add_process (pid, 1);
1193
1194 /* Don't ignore the initial SIGSTOP if we just attached to this
1195 process. It will be collected by wait shortly. */
1196 initial_thread = find_thread_ptid (ptid_build (pid, pid, 0));
1197 initial_thread->last_resume_kind = resume_stop;
1198
1199 /* We must attach to every LWP. If /proc is mounted, use that to
1200 find them now. On the one hand, the inferior may be using raw
1201 clone instead of using pthreads. On the other hand, even if it
1202 is using pthreads, GDB may not be connected yet (thread_db needs
1203 to do symbol lookups, through qSymbol). Also, thread_db walks
1204 structures in the inferior's address space to find the list of
1205 threads/LWPs, and those structures may well be corrupted. Note
1206 that once thread_db is loaded, we'll still use it to list threads
1207 and associate pthread info with each LWP. */
1208 linux_proc_attach_tgid_threads (pid, attach_proc_task_lwp_callback);
1209
1210 /* GDB will shortly read the xml target description for this
1211 process, to figure out the process' architecture. But the target
1212 description is only filled in when the first process/thread in
1213 the thread group reports its initial PTRACE_ATTACH SIGSTOP. Do
1214 that now, otherwise, if GDB is fast enough, it could read the
1215 target description _before_ that initial stop. */
1216 if (non_stop)
1217 {
1218 struct lwp_info *lwp;
1219 int wstat, lwpid;
1220 ptid_t pid_ptid = pid_to_ptid (pid);
1221
1222 lwpid = linux_wait_for_event_filtered (pid_ptid, pid_ptid,
1223 &wstat, __WALL);
1224 gdb_assert (lwpid > 0);
1225
1226 lwp = find_lwp_pid (pid_to_ptid (lwpid));
1227
1228 if (!WIFSTOPPED (wstat) || WSTOPSIG (wstat) != SIGSTOP)
1229 {
1230 lwp->status_pending_p = 1;
1231 lwp->status_pending = wstat;
1232 }
1233
1234 initial_thread->last_resume_kind = resume_continue;
1235
1236 async_file_mark ();
1237
1238 gdb_assert (proc->tdesc != NULL);
1239 }
1240
1241 return 0;
1242 }
1243
1244 struct counter
1245 {
1246 int pid;
1247 int count;
1248 };
1249
1250 static int
1251 second_thread_of_pid_p (thread_info *thread, void *args)
1252 {
1253 struct counter *counter = (struct counter *) args;
1254
1255 if (thread->id.pid () == counter->pid)
1256 {
1257 if (++counter->count > 1)
1258 return 1;
1259 }
1260
1261 return 0;
1262 }
1263
1264 static int
1265 last_thread_of_process_p (int pid)
1266 {
1267 struct counter counter = { pid , 0 };
1268
1269 return (find_inferior (&all_threads,
1270 second_thread_of_pid_p, &counter) == NULL);
1271 }
1272
1273 /* Kill LWP. */
1274
1275 static void
1276 linux_kill_one_lwp (struct lwp_info *lwp)
1277 {
1278 struct thread_info *thr = get_lwp_thread (lwp);
1279 int pid = lwpid_of (thr);
1280
1281 /* PTRACE_KILL is unreliable. After stepping into a signal handler,
1282 there is no signal context, and ptrace(PTRACE_KILL) (or
1283 ptrace(PTRACE_CONT, SIGKILL), pretty much the same) acts like
1284 ptrace(CONT, pid, 0,0) and just resumes the tracee. A better
1285 alternative is to kill with SIGKILL. We only need one SIGKILL
1286 per process, not one for each thread. But since we still support
1287 support debugging programs using raw clone without CLONE_THREAD,
1288 we send one for each thread. For years, we used PTRACE_KILL
1289 only, so we're being a bit paranoid about some old kernels where
1290 PTRACE_KILL might work better (dubious if there are any such, but
1291 that's why it's paranoia), so we try SIGKILL first, PTRACE_KILL
1292 second, and so we're fine everywhere. */
1293
1294 errno = 0;
1295 kill_lwp (pid, SIGKILL);
1296 if (debug_threads)
1297 {
1298 int save_errno = errno;
1299
1300 debug_printf ("LKL: kill_lwp (SIGKILL) %s, 0, 0 (%s)\n",
1301 target_pid_to_str (ptid_of (thr)),
1302 save_errno ? strerror (save_errno) : "OK");
1303 }
1304
1305 errno = 0;
1306 ptrace (PTRACE_KILL, pid, (PTRACE_TYPE_ARG3) 0, (PTRACE_TYPE_ARG4) 0);
1307 if (debug_threads)
1308 {
1309 int save_errno = errno;
1310
1311 debug_printf ("LKL: PTRACE_KILL %s, 0, 0 (%s)\n",
1312 target_pid_to_str (ptid_of (thr)),
1313 save_errno ? strerror (save_errno) : "OK");
1314 }
1315 }
1316
1317 /* Kill LWP and wait for it to die. */
1318
1319 static void
1320 kill_wait_lwp (struct lwp_info *lwp)
1321 {
1322 struct thread_info *thr = get_lwp_thread (lwp);
1323 int pid = ptid_get_pid (ptid_of (thr));
1324 int lwpid = ptid_get_lwp (ptid_of (thr));
1325 int wstat;
1326 int res;
1327
1328 if (debug_threads)
1329 debug_printf ("kwl: killing lwp %d, for pid: %d\n", lwpid, pid);
1330
1331 do
1332 {
1333 linux_kill_one_lwp (lwp);
1334
1335 /* Make sure it died. Notes:
1336
1337 - The loop is most likely unnecessary.
1338
1339 - We don't use linux_wait_for_event as that could delete lwps
1340 while we're iterating over them. We're not interested in
1341 any pending status at this point, only in making sure all
1342 wait status on the kernel side are collected until the
1343 process is reaped.
1344
1345 - We don't use __WALL here as the __WALL emulation relies on
1346 SIGCHLD, and killing a stopped process doesn't generate
1347 one, nor an exit status.
1348 */
1349 res = my_waitpid (lwpid, &wstat, 0);
1350 if (res == -1 && errno == ECHILD)
1351 res = my_waitpid (lwpid, &wstat, __WCLONE);
1352 } while (res > 0 && WIFSTOPPED (wstat));
1353
1354 /* Even if it was stopped, the child may have already disappeared.
1355 E.g., if it was killed by SIGKILL. */
1356 if (res < 0 && errno != ECHILD)
1357 perror_with_name ("kill_wait_lwp");
1358 }
1359
1360 /* Callback for `find_inferior'. Kills an lwp of a given process,
1361 except the leader. */
1362
1363 static int
1364 kill_one_lwp_callback (thread_info *thread, void *args)
1365 {
1366 struct lwp_info *lwp = get_thread_lwp (thread);
1367 int pid = * (int *) args;
1368
1369 if (thread->id.pid () != pid)
1370 return 0;
1371
1372 /* We avoid killing the first thread here, because of a Linux kernel (at
1373 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
1374 the children get a chance to be reaped, it will remain a zombie
1375 forever. */
1376
1377 if (lwpid_of (thread) == pid)
1378 {
1379 if (debug_threads)
1380 debug_printf ("lkop: is last of process %s\n",
1381 target_pid_to_str (thread->id));
1382 return 0;
1383 }
1384
1385 kill_wait_lwp (lwp);
1386 return 0;
1387 }
1388
1389 static int
1390 linux_kill (int pid)
1391 {
1392 struct process_info *process;
1393 struct lwp_info *lwp;
1394
1395 process = find_process_pid (pid);
1396 if (process == NULL)
1397 return -1;
1398
1399 /* If we're killing a running inferior, make sure it is stopped
1400 first, as PTRACE_KILL will not work otherwise. */
1401 stop_all_lwps (0, NULL);
1402
1403 find_inferior (&all_threads, kill_one_lwp_callback , &pid);
1404
1405 /* See the comment in linux_kill_one_lwp. We did not kill the first
1406 thread in the list, so do so now. */
1407 lwp = find_lwp_pid (pid_to_ptid (pid));
1408
1409 if (lwp == NULL)
1410 {
1411 if (debug_threads)
1412 debug_printf ("lk_1: cannot find lwp for pid: %d\n",
1413 pid);
1414 }
1415 else
1416 kill_wait_lwp (lwp);
1417
1418 the_target->mourn (process);
1419
1420 /* Since we presently can only stop all lwps of all processes, we
1421 need to unstop lwps of other processes. */
1422 unstop_all_lwps (0, NULL);
1423 return 0;
1424 }
1425
1426 /* Get pending signal of THREAD, for detaching purposes. This is the
1427 signal the thread last stopped for, which we need to deliver to the
1428 thread when detaching, otherwise, it'd be suppressed/lost. */
1429
1430 static int
1431 get_detach_signal (struct thread_info *thread)
1432 {
1433 enum gdb_signal signo = GDB_SIGNAL_0;
1434 int status;
1435 struct lwp_info *lp = get_thread_lwp (thread);
1436
1437 if (lp->status_pending_p)
1438 status = lp->status_pending;
1439 else
1440 {
1441 /* If the thread had been suspended by gdbserver, and it stopped
1442 cleanly, then it'll have stopped with SIGSTOP. But we don't
1443 want to deliver that SIGSTOP. */
1444 if (thread->last_status.kind != TARGET_WAITKIND_STOPPED
1445 || thread->last_status.value.sig == GDB_SIGNAL_0)
1446 return 0;
1447
1448 /* Otherwise, we may need to deliver the signal we
1449 intercepted. */
1450 status = lp->last_status;
1451 }
1452
1453 if (!WIFSTOPPED (status))
1454 {
1455 if (debug_threads)
1456 debug_printf ("GPS: lwp %s hasn't stopped: no pending signal\n",
1457 target_pid_to_str (ptid_of (thread)));
1458 return 0;
1459 }
1460
1461 /* Extended wait statuses aren't real SIGTRAPs. */
1462 if (WSTOPSIG (status) == SIGTRAP && linux_is_extended_waitstatus (status))
1463 {
1464 if (debug_threads)
1465 debug_printf ("GPS: lwp %s had stopped with extended "
1466 "status: no pending signal\n",
1467 target_pid_to_str (ptid_of (thread)));
1468 return 0;
1469 }
1470
1471 signo = gdb_signal_from_host (WSTOPSIG (status));
1472
1473 if (program_signals_p && !program_signals[signo])
1474 {
1475 if (debug_threads)
1476 debug_printf ("GPS: lwp %s had signal %s, but it is in nopass state\n",
1477 target_pid_to_str (ptid_of (thread)),
1478 gdb_signal_to_string (signo));
1479 return 0;
1480 }
1481 else if (!program_signals_p
1482 /* If we have no way to know which signals GDB does not
1483 want to have passed to the program, assume
1484 SIGTRAP/SIGINT, which is GDB's default. */
1485 && (signo == GDB_SIGNAL_TRAP || signo == GDB_SIGNAL_INT))
1486 {
1487 if (debug_threads)
1488 debug_printf ("GPS: lwp %s had signal %s, "
1489 "but we don't know if we should pass it. "
1490 "Default to not.\n",
1491 target_pid_to_str (ptid_of (thread)),
1492 gdb_signal_to_string (signo));
1493 return 0;
1494 }
1495 else
1496 {
1497 if (debug_threads)
1498 debug_printf ("GPS: lwp %s has pending signal %s: delivering it.\n",
1499 target_pid_to_str (ptid_of (thread)),
1500 gdb_signal_to_string (signo));
1501
1502 return WSTOPSIG (status);
1503 }
1504 }
1505
1506 /* Detach from LWP. */
1507
1508 static void
1509 linux_detach_one_lwp (struct lwp_info *lwp)
1510 {
1511 struct thread_info *thread = get_lwp_thread (lwp);
1512 int sig;
1513 int lwpid;
1514
1515 /* If there is a pending SIGSTOP, get rid of it. */
1516 if (lwp->stop_expected)
1517 {
1518 if (debug_threads)
1519 debug_printf ("Sending SIGCONT to %s\n",
1520 target_pid_to_str (ptid_of (thread)));
1521
1522 kill_lwp (lwpid_of (thread), SIGCONT);
1523 lwp->stop_expected = 0;
1524 }
1525
1526 /* Pass on any pending signal for this thread. */
1527 sig = get_detach_signal (thread);
1528
1529 /* Preparing to resume may try to write registers, and fail if the
1530 lwp is zombie. If that happens, ignore the error. We'll handle
1531 it below, when detach fails with ESRCH. */
1532 TRY
1533 {
1534 /* Flush any pending changes to the process's registers. */
1535 regcache_invalidate_thread (thread);
1536
1537 /* Finally, let it resume. */
1538 if (the_low_target.prepare_to_resume != NULL)
1539 the_low_target.prepare_to_resume (lwp);
1540 }
1541 CATCH (ex, RETURN_MASK_ERROR)
1542 {
1543 if (!check_ptrace_stopped_lwp_gone (lwp))
1544 throw_exception (ex);
1545 }
1546 END_CATCH
1547
1548 lwpid = lwpid_of (thread);
1549 if (ptrace (PTRACE_DETACH, lwpid, (PTRACE_TYPE_ARG3) 0,
1550 (PTRACE_TYPE_ARG4) (long) sig) < 0)
1551 {
1552 int save_errno = errno;
1553
1554 /* We know the thread exists, so ESRCH must mean the lwp is
1555 zombie. This can happen if one of the already-detached
1556 threads exits the whole thread group. In that case we're
1557 still attached, and must reap the lwp. */
1558 if (save_errno == ESRCH)
1559 {
1560 int ret, status;
1561
1562 ret = my_waitpid (lwpid, &status, __WALL);
1563 if (ret == -1)
1564 {
1565 warning (_("Couldn't reap LWP %d while detaching: %s"),
1566 lwpid, strerror (errno));
1567 }
1568 else if (!WIFEXITED (status) && !WIFSIGNALED (status))
1569 {
1570 warning (_("Reaping LWP %d while detaching "
1571 "returned unexpected status 0x%x"),
1572 lwpid, status);
1573 }
1574 }
1575 else
1576 {
1577 error (_("Can't detach %s: %s"),
1578 target_pid_to_str (ptid_of (thread)),
1579 strerror (save_errno));
1580 }
1581 }
1582 else if (debug_threads)
1583 {
1584 debug_printf ("PTRACE_DETACH (%s, %s, 0) (OK)\n",
1585 target_pid_to_str (ptid_of (thread)),
1586 strsignal (sig));
1587 }
1588
1589 delete_lwp (lwp);
1590 }
1591
1592 /* Callback for find_inferior. Detaches from non-leader threads of a
1593 given process. */
1594
1595 static int
1596 linux_detach_lwp_callback (thread_info *thread, void *args)
1597 {
1598 struct lwp_info *lwp = get_thread_lwp (thread);
1599 int pid = *(int *) args;
1600 int lwpid = lwpid_of (thread);
1601
1602 /* Skip other processes. */
1603 if (thread->id.pid () != pid)
1604 return 0;
1605
1606 /* We don't actually detach from the thread group leader just yet.
1607 If the thread group exits, we must reap the zombie clone lwps
1608 before we're able to reap the leader. */
1609 if (thread->id.pid () == lwpid)
1610 return 0;
1611
1612 linux_detach_one_lwp (lwp);
1613 return 0;
1614 }
1615
1616 static int
1617 linux_detach (int pid)
1618 {
1619 struct process_info *process;
1620 struct lwp_info *main_lwp;
1621
1622 process = find_process_pid (pid);
1623 if (process == NULL)
1624 return -1;
1625
1626 /* As there's a step over already in progress, let it finish first,
1627 otherwise nesting a stabilize_threads operation on top gets real
1628 messy. */
1629 complete_ongoing_step_over ();
1630
1631 /* Stop all threads before detaching. First, ptrace requires that
1632 the thread is stopped to sucessfully detach. Second, thread_db
1633 may need to uninstall thread event breakpoints from memory, which
1634 only works with a stopped process anyway. */
1635 stop_all_lwps (0, NULL);
1636
1637 #ifdef USE_THREAD_DB
1638 thread_db_detach (process);
1639 #endif
1640
1641 /* Stabilize threads (move out of jump pads). */
1642 stabilize_threads ();
1643
1644 /* Detach from the clone lwps first. If the thread group exits just
1645 while we're detaching, we must reap the clone lwps before we're
1646 able to reap the leader. */
1647 find_inferior (&all_threads, linux_detach_lwp_callback, &pid);
1648
1649 main_lwp = find_lwp_pid (pid_to_ptid (pid));
1650 linux_detach_one_lwp (main_lwp);
1651
1652 the_target->mourn (process);
1653
1654 /* Since we presently can only stop all lwps of all processes, we
1655 need to unstop lwps of other processes. */
1656 unstop_all_lwps (0, NULL);
1657 return 0;
1658 }
1659
1660 /* Remove all LWPs that belong to process PROC from the lwp list. */
1661
1662 static int
1663 delete_lwp_callback (thread_info *thread, void *proc)
1664 {
1665 struct lwp_info *lwp = get_thread_lwp (thread);
1666 struct process_info *process = (struct process_info *) proc;
1667
1668 if (pid_of (thread) == pid_of (process))
1669 delete_lwp (lwp);
1670
1671 return 0;
1672 }
1673
1674 static void
1675 linux_mourn (struct process_info *process)
1676 {
1677 struct process_info_private *priv;
1678
1679 #ifdef USE_THREAD_DB
1680 thread_db_mourn (process);
1681 #endif
1682
1683 find_inferior (&all_threads, delete_lwp_callback, process);
1684
1685 /* Freeing all private data. */
1686 priv = process->priv;
1687 if (the_low_target.delete_process != NULL)
1688 the_low_target.delete_process (priv->arch_private);
1689 else
1690 gdb_assert (priv->arch_private == NULL);
1691 free (priv);
1692 process->priv = NULL;
1693
1694 remove_process (process);
1695 }
1696
1697 static void
1698 linux_join (int pid)
1699 {
1700 int status, ret;
1701
1702 do {
1703 ret = my_waitpid (pid, &status, 0);
1704 if (WIFEXITED (status) || WIFSIGNALED (status))
1705 break;
1706 } while (ret != -1 || errno != ECHILD);
1707 }
1708
1709 /* Return nonzero if the given thread is still alive. */
1710 static int
1711 linux_thread_alive (ptid_t ptid)
1712 {
1713 struct lwp_info *lwp = find_lwp_pid (ptid);
1714
1715 /* We assume we always know if a thread exits. If a whole process
1716 exited but we still haven't been able to report it to GDB, we'll
1717 hold on to the last lwp of the dead process. */
1718 if (lwp != NULL)
1719 return !lwp_is_marked_dead (lwp);
1720 else
1721 return 0;
1722 }
1723
1724 /* Return 1 if this lwp still has an interesting status pending. If
1725 not (e.g., it had stopped for a breakpoint that is gone), return
1726 false. */
1727
1728 static int
1729 thread_still_has_status_pending_p (struct thread_info *thread)
1730 {
1731 struct lwp_info *lp = get_thread_lwp (thread);
1732
1733 if (!lp->status_pending_p)
1734 return 0;
1735
1736 if (thread->last_resume_kind != resume_stop
1737 && (lp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT
1738 || lp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT))
1739 {
1740 struct thread_info *saved_thread;
1741 CORE_ADDR pc;
1742 int discard = 0;
1743
1744 gdb_assert (lp->last_status != 0);
1745
1746 pc = get_pc (lp);
1747
1748 saved_thread = current_thread;
1749 current_thread = thread;
1750
1751 if (pc != lp->stop_pc)
1752 {
1753 if (debug_threads)
1754 debug_printf ("PC of %ld changed\n",
1755 lwpid_of (thread));
1756 discard = 1;
1757 }
1758
1759 #if !USE_SIGTRAP_SIGINFO
1760 else if (lp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT
1761 && !(*the_low_target.breakpoint_at) (pc))
1762 {
1763 if (debug_threads)
1764 debug_printf ("previous SW breakpoint of %ld gone\n",
1765 lwpid_of (thread));
1766 discard = 1;
1767 }
1768 else if (lp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT
1769 && !hardware_breakpoint_inserted_here (pc))
1770 {
1771 if (debug_threads)
1772 debug_printf ("previous HW breakpoint of %ld gone\n",
1773 lwpid_of (thread));
1774 discard = 1;
1775 }
1776 #endif
1777
1778 current_thread = saved_thread;
1779
1780 if (discard)
1781 {
1782 if (debug_threads)
1783 debug_printf ("discarding pending breakpoint status\n");
1784 lp->status_pending_p = 0;
1785 return 0;
1786 }
1787 }
1788
1789 return 1;
1790 }
1791
1792 /* Returns true if LWP is resumed from the client's perspective. */
1793
1794 static int
1795 lwp_resumed (struct lwp_info *lwp)
1796 {
1797 struct thread_info *thread = get_lwp_thread (lwp);
1798
1799 if (thread->last_resume_kind != resume_stop)
1800 return 1;
1801
1802 /* Did gdb send us a `vCont;t', but we haven't reported the
1803 corresponding stop to gdb yet? If so, the thread is still
1804 resumed/running from gdb's perspective. */
1805 if (thread->last_resume_kind == resume_stop
1806 && thread->last_status.kind == TARGET_WAITKIND_IGNORE)
1807 return 1;
1808
1809 return 0;
1810 }
1811
1812 /* Return 1 if this lwp has an interesting status pending. */
1813 static int
1814 status_pending_p_callback (thread_info *thread, void *arg)
1815 {
1816 struct lwp_info *lp = get_thread_lwp (thread);
1817 ptid_t ptid = * (ptid_t *) arg;
1818
1819 /* Check if we're only interested in events from a specific process
1820 or a specific LWP. */
1821 if (!ptid_match (ptid_of (thread), ptid))
1822 return 0;
1823
1824 if (!lwp_resumed (lp))
1825 return 0;
1826
1827 if (lp->status_pending_p
1828 && !thread_still_has_status_pending_p (thread))
1829 {
1830 linux_resume_one_lwp (lp, lp->stepping, GDB_SIGNAL_0, NULL);
1831 return 0;
1832 }
1833
1834 return lp->status_pending_p;
1835 }
1836
1837 static int
1838 same_lwp (thread_info *thread, void *data)
1839 {
1840 ptid_t ptid = *(ptid_t *) data;
1841 int lwp;
1842
1843 if (ptid_get_lwp (ptid) != 0)
1844 lwp = ptid_get_lwp (ptid);
1845 else
1846 lwp = ptid_get_pid (ptid);
1847
1848 if (thread->id.lwp () == lwp)
1849 return 1;
1850
1851 return 0;
1852 }
1853
1854 struct lwp_info *
1855 find_lwp_pid (ptid_t ptid)
1856 {
1857 thread_info *thread = find_inferior (&all_threads, same_lwp, &ptid);
1858
1859 if (thread == NULL)
1860 return NULL;
1861
1862 return get_thread_lwp (thread);
1863 }
1864
1865 /* Return the number of known LWPs in the tgid given by PID. */
1866
1867 static int
1868 num_lwps (int pid)
1869 {
1870 int count = 0;
1871
1872 for_each_thread (pid, [&] (thread_info *thread)
1873 {
1874 count++;
1875 });
1876
1877 return count;
1878 }
1879
1880 /* The arguments passed to iterate_over_lwps. */
1881
1882 struct iterate_over_lwps_args
1883 {
1884 /* The FILTER argument passed to iterate_over_lwps. */
1885 ptid_t filter;
1886
1887 /* The CALLBACK argument passed to iterate_over_lwps. */
1888 iterate_over_lwps_ftype *callback;
1889
1890 /* The DATA argument passed to iterate_over_lwps. */
1891 void *data;
1892 };
1893
1894 /* Callback for find_inferior used by iterate_over_lwps to filter
1895 calls to the callback supplied to that function. Returning a
1896 nonzero value causes find_inferiors to stop iterating and return
1897 the current inferior_list_entry. Returning zero indicates that
1898 find_inferiors should continue iterating. */
1899
1900 static int
1901 iterate_over_lwps_filter (thread_info *thread, void *args_p)
1902 {
1903 struct iterate_over_lwps_args *args
1904 = (struct iterate_over_lwps_args *) args_p;
1905
1906 if (thread->id.matches (args->filter))
1907 {
1908 struct lwp_info *lwp = get_thread_lwp (thread);
1909
1910 return (*args->callback) (lwp, args->data);
1911 }
1912
1913 return 0;
1914 }
1915
1916 /* See nat/linux-nat.h. */
1917
1918 struct lwp_info *
1919 iterate_over_lwps (ptid_t filter,
1920 iterate_over_lwps_ftype callback,
1921 void *data)
1922 {
1923 struct iterate_over_lwps_args args = {filter, callback, data};
1924
1925 thread_info *thread = find_inferior (&all_threads, iterate_over_lwps_filter,
1926 &args);
1927 if (thread == NULL)
1928 return NULL;
1929
1930 return get_thread_lwp (thread);
1931 }
1932
1933 /* Detect zombie thread group leaders, and "exit" them. We can't reap
1934 their exits until all other threads in the group have exited. */
1935
1936 static void
1937 check_zombie_leaders (void)
1938 {
1939 for_each_process ([] (process_info *proc) {
1940 pid_t leader_pid = pid_of (proc);
1941 struct lwp_info *leader_lp;
1942
1943 leader_lp = find_lwp_pid (pid_to_ptid (leader_pid));
1944
1945 if (debug_threads)
1946 debug_printf ("leader_pid=%d, leader_lp!=NULL=%d, "
1947 "num_lwps=%d, zombie=%d\n",
1948 leader_pid, leader_lp!= NULL, num_lwps (leader_pid),
1949 linux_proc_pid_is_zombie (leader_pid));
1950
1951 if (leader_lp != NULL && !leader_lp->stopped
1952 /* Check if there are other threads in the group, as we may
1953 have raced with the inferior simply exiting. */
1954 && !last_thread_of_process_p (leader_pid)
1955 && linux_proc_pid_is_zombie (leader_pid))
1956 {
1957 /* A leader zombie can mean one of two things:
1958
1959 - It exited, and there's an exit status pending
1960 available, or only the leader exited (not the whole
1961 program). In the latter case, we can't waitpid the
1962 leader's exit status until all other threads are gone.
1963
1964 - There are 3 or more threads in the group, and a thread
1965 other than the leader exec'd. On an exec, the Linux
1966 kernel destroys all other threads (except the execing
1967 one) in the thread group, and resets the execing thread's
1968 tid to the tgid. No exit notification is sent for the
1969 execing thread -- from the ptracer's perspective, it
1970 appears as though the execing thread just vanishes.
1971 Until we reap all other threads except the leader and the
1972 execing thread, the leader will be zombie, and the
1973 execing thread will be in `D (disc sleep)'. As soon as
1974 all other threads are reaped, the execing thread changes
1975 it's tid to the tgid, and the previous (zombie) leader
1976 vanishes, giving place to the "new" leader. We could try
1977 distinguishing the exit and exec cases, by waiting once
1978 more, and seeing if something comes out, but it doesn't
1979 sound useful. The previous leader _does_ go away, and
1980 we'll re-add the new one once we see the exec event
1981 (which is just the same as what would happen if the
1982 previous leader did exit voluntarily before some other
1983 thread execs). */
1984
1985 if (debug_threads)
1986 debug_printf ("CZL: Thread group leader %d zombie "
1987 "(it exited, or another thread execd).\n",
1988 leader_pid);
1989
1990 delete_lwp (leader_lp);
1991 }
1992 });
1993 }
1994
1995 /* Callback for `find_inferior'. Returns the first LWP that is not
1996 stopped. ARG is a PTID filter. */
1997
1998 static int
1999 not_stopped_callback (thread_info *thread, void *arg)
2000 {
2001 struct lwp_info *lwp;
2002 ptid_t filter = *(ptid_t *) arg;
2003
2004 if (!ptid_match (ptid_of (thread), filter))
2005 return 0;
2006
2007 lwp = get_thread_lwp (thread);
2008 if (!lwp->stopped)
2009 return 1;
2010
2011 return 0;
2012 }
2013
2014 /* Increment LWP's suspend count. */
2015
2016 static void
2017 lwp_suspended_inc (struct lwp_info *lwp)
2018 {
2019 lwp->suspended++;
2020
2021 if (debug_threads && lwp->suspended > 4)
2022 {
2023 struct thread_info *thread = get_lwp_thread (lwp);
2024
2025 debug_printf ("LWP %ld has a suspiciously high suspend count,"
2026 " suspended=%d\n", lwpid_of (thread), lwp->suspended);
2027 }
2028 }
2029
2030 /* Decrement LWP's suspend count. */
2031
2032 static void
2033 lwp_suspended_decr (struct lwp_info *lwp)
2034 {
2035 lwp->suspended--;
2036
2037 if (lwp->suspended < 0)
2038 {
2039 struct thread_info *thread = get_lwp_thread (lwp);
2040
2041 internal_error (__FILE__, __LINE__,
2042 "unsuspend LWP %ld, suspended=%d\n", lwpid_of (thread),
2043 lwp->suspended);
2044 }
2045 }
2046
2047 /* This function should only be called if the LWP got a SIGTRAP.
2048
2049 Handle any tracepoint steps or hits. Return true if a tracepoint
2050 event was handled, 0 otherwise. */
2051
2052 static int
2053 handle_tracepoints (struct lwp_info *lwp)
2054 {
2055 struct thread_info *tinfo = get_lwp_thread (lwp);
2056 int tpoint_related_event = 0;
2057
2058 gdb_assert (lwp->suspended == 0);
2059
2060 /* If this tracepoint hit causes a tracing stop, we'll immediately
2061 uninsert tracepoints. To do this, we temporarily pause all
2062 threads, unpatch away, and then unpause threads. We need to make
2063 sure the unpausing doesn't resume LWP too. */
2064 lwp_suspended_inc (lwp);
2065
2066 /* And we need to be sure that any all-threads-stopping doesn't try
2067 to move threads out of the jump pads, as it could deadlock the
2068 inferior (LWP could be in the jump pad, maybe even holding the
2069 lock.) */
2070
2071 /* Do any necessary step collect actions. */
2072 tpoint_related_event |= tracepoint_finished_step (tinfo, lwp->stop_pc);
2073
2074 tpoint_related_event |= handle_tracepoint_bkpts (tinfo, lwp->stop_pc);
2075
2076 /* See if we just hit a tracepoint and do its main collect
2077 actions. */
2078 tpoint_related_event |= tracepoint_was_hit (tinfo, lwp->stop_pc);
2079
2080 lwp_suspended_decr (lwp);
2081
2082 gdb_assert (lwp->suspended == 0);
2083 gdb_assert (!stabilizing_threads
2084 || (lwp->collecting_fast_tracepoint
2085 != fast_tpoint_collect_result::not_collecting));
2086
2087 if (tpoint_related_event)
2088 {
2089 if (debug_threads)
2090 debug_printf ("got a tracepoint event\n");
2091 return 1;
2092 }
2093
2094 return 0;
2095 }
2096
2097 /* Convenience wrapper. Returns information about LWP's fast tracepoint
2098 collection status. */
2099
2100 static fast_tpoint_collect_result
2101 linux_fast_tracepoint_collecting (struct lwp_info *lwp,
2102 struct fast_tpoint_collect_status *status)
2103 {
2104 CORE_ADDR thread_area;
2105 struct thread_info *thread = get_lwp_thread (lwp);
2106
2107 if (the_low_target.get_thread_area == NULL)
2108 return fast_tpoint_collect_result::not_collecting;
2109
2110 /* Get the thread area address. This is used to recognize which
2111 thread is which when tracing with the in-process agent library.
2112 We don't read anything from the address, and treat it as opaque;
2113 it's the address itself that we assume is unique per-thread. */
2114 if ((*the_low_target.get_thread_area) (lwpid_of (thread), &thread_area) == -1)
2115 return fast_tpoint_collect_result::not_collecting;
2116
2117 return fast_tracepoint_collecting (thread_area, lwp->stop_pc, status);
2118 }
2119
2120 /* The reason we resume in the caller, is because we want to be able
2121 to pass lwp->status_pending as WSTAT, and we need to clear
2122 status_pending_p before resuming, otherwise, linux_resume_one_lwp
2123 refuses to resume. */
2124
2125 static int
2126 maybe_move_out_of_jump_pad (struct lwp_info *lwp, int *wstat)
2127 {
2128 struct thread_info *saved_thread;
2129
2130 saved_thread = current_thread;
2131 current_thread = get_lwp_thread (lwp);
2132
2133 if ((wstat == NULL
2134 || (WIFSTOPPED (*wstat) && WSTOPSIG (*wstat) != SIGTRAP))
2135 && supports_fast_tracepoints ()
2136 && agent_loaded_p ())
2137 {
2138 struct fast_tpoint_collect_status status;
2139
2140 if (debug_threads)
2141 debug_printf ("Checking whether LWP %ld needs to move out of the "
2142 "jump pad.\n",
2143 lwpid_of (current_thread));
2144
2145 fast_tpoint_collect_result r
2146 = linux_fast_tracepoint_collecting (lwp, &status);
2147
2148 if (wstat == NULL
2149 || (WSTOPSIG (*wstat) != SIGILL
2150 && WSTOPSIG (*wstat) != SIGFPE
2151 && WSTOPSIG (*wstat) != SIGSEGV
2152 && WSTOPSIG (*wstat) != SIGBUS))
2153 {
2154 lwp->collecting_fast_tracepoint = r;
2155
2156 if (r != fast_tpoint_collect_result::not_collecting)
2157 {
2158 if (r == fast_tpoint_collect_result::before_insn
2159 && lwp->exit_jump_pad_bkpt == NULL)
2160 {
2161 /* Haven't executed the original instruction yet.
2162 Set breakpoint there, and wait till it's hit,
2163 then single-step until exiting the jump pad. */
2164 lwp->exit_jump_pad_bkpt
2165 = set_breakpoint_at (status.adjusted_insn_addr, NULL);
2166 }
2167
2168 if (debug_threads)
2169 debug_printf ("Checking whether LWP %ld needs to move out of "
2170 "the jump pad...it does\n",
2171 lwpid_of (current_thread));
2172 current_thread = saved_thread;
2173
2174 return 1;
2175 }
2176 }
2177 else
2178 {
2179 /* If we get a synchronous signal while collecting, *and*
2180 while executing the (relocated) original instruction,
2181 reset the PC to point at the tpoint address, before
2182 reporting to GDB. Otherwise, it's an IPA lib bug: just
2183 report the signal to GDB, and pray for the best. */
2184
2185 lwp->collecting_fast_tracepoint
2186 = fast_tpoint_collect_result::not_collecting;
2187
2188 if (r != fast_tpoint_collect_result::not_collecting
2189 && (status.adjusted_insn_addr <= lwp->stop_pc
2190 && lwp->stop_pc < status.adjusted_insn_addr_end))
2191 {
2192 siginfo_t info;
2193 struct regcache *regcache;
2194
2195 /* The si_addr on a few signals references the address
2196 of the faulting instruction. Adjust that as
2197 well. */
2198 if ((WSTOPSIG (*wstat) == SIGILL
2199 || WSTOPSIG (*wstat) == SIGFPE
2200 || WSTOPSIG (*wstat) == SIGBUS
2201 || WSTOPSIG (*wstat) == SIGSEGV)
2202 && ptrace (PTRACE_GETSIGINFO, lwpid_of (current_thread),
2203 (PTRACE_TYPE_ARG3) 0, &info) == 0
2204 /* Final check just to make sure we don't clobber
2205 the siginfo of non-kernel-sent signals. */
2206 && (uintptr_t) info.si_addr == lwp->stop_pc)
2207 {
2208 info.si_addr = (void *) (uintptr_t) status.tpoint_addr;
2209 ptrace (PTRACE_SETSIGINFO, lwpid_of (current_thread),
2210 (PTRACE_TYPE_ARG3) 0, &info);
2211 }
2212
2213 regcache = get_thread_regcache (current_thread, 1);
2214 (*the_low_target.set_pc) (regcache, status.tpoint_addr);
2215 lwp->stop_pc = status.tpoint_addr;
2216
2217 /* Cancel any fast tracepoint lock this thread was
2218 holding. */
2219 force_unlock_trace_buffer ();
2220 }
2221
2222 if (lwp->exit_jump_pad_bkpt != NULL)
2223 {
2224 if (debug_threads)
2225 debug_printf ("Cancelling fast exit-jump-pad: removing bkpt. "
2226 "stopping all threads momentarily.\n");
2227
2228 stop_all_lwps (1, lwp);
2229
2230 delete_breakpoint (lwp->exit_jump_pad_bkpt);
2231 lwp->exit_jump_pad_bkpt = NULL;
2232
2233 unstop_all_lwps (1, lwp);
2234
2235 gdb_assert (lwp->suspended >= 0);
2236 }
2237 }
2238 }
2239
2240 if (debug_threads)
2241 debug_printf ("Checking whether LWP %ld needs to move out of the "
2242 "jump pad...no\n",
2243 lwpid_of (current_thread));
2244
2245 current_thread = saved_thread;
2246 return 0;
2247 }
2248
2249 /* Enqueue one signal in the "signals to report later when out of the
2250 jump pad" list. */
2251
2252 static void
2253 enqueue_one_deferred_signal (struct lwp_info *lwp, int *wstat)
2254 {
2255 struct pending_signals *p_sig;
2256 struct thread_info *thread = get_lwp_thread (lwp);
2257
2258 if (debug_threads)
2259 debug_printf ("Deferring signal %d for LWP %ld.\n",
2260 WSTOPSIG (*wstat), lwpid_of (thread));
2261
2262 if (debug_threads)
2263 {
2264 struct pending_signals *sig;
2265
2266 for (sig = lwp->pending_signals_to_report;
2267 sig != NULL;
2268 sig = sig->prev)
2269 debug_printf (" Already queued %d\n",
2270 sig->signal);
2271
2272 debug_printf (" (no more currently queued signals)\n");
2273 }
2274
2275 /* Don't enqueue non-RT signals if they are already in the deferred
2276 queue. (SIGSTOP being the easiest signal to see ending up here
2277 twice) */
2278 if (WSTOPSIG (*wstat) < __SIGRTMIN)
2279 {
2280 struct pending_signals *sig;
2281
2282 for (sig = lwp->pending_signals_to_report;
2283 sig != NULL;
2284 sig = sig->prev)
2285 {
2286 if (sig->signal == WSTOPSIG (*wstat))
2287 {
2288 if (debug_threads)
2289 debug_printf ("Not requeuing already queued non-RT signal %d"
2290 " for LWP %ld\n",
2291 sig->signal,
2292 lwpid_of (thread));
2293 return;
2294 }
2295 }
2296 }
2297
2298 p_sig = XCNEW (struct pending_signals);
2299 p_sig->prev = lwp->pending_signals_to_report;
2300 p_sig->signal = WSTOPSIG (*wstat);
2301
2302 ptrace (PTRACE_GETSIGINFO, lwpid_of (thread), (PTRACE_TYPE_ARG3) 0,
2303 &p_sig->info);
2304
2305 lwp->pending_signals_to_report = p_sig;
2306 }
2307
2308 /* Dequeue one signal from the "signals to report later when out of
2309 the jump pad" list. */
2310
2311 static int
2312 dequeue_one_deferred_signal (struct lwp_info *lwp, int *wstat)
2313 {
2314 struct thread_info *thread = get_lwp_thread (lwp);
2315
2316 if (lwp->pending_signals_to_report != NULL)
2317 {
2318 struct pending_signals **p_sig;
2319
2320 p_sig = &lwp->pending_signals_to_report;
2321 while ((*p_sig)->prev != NULL)
2322 p_sig = &(*p_sig)->prev;
2323
2324 *wstat = W_STOPCODE ((*p_sig)->signal);
2325 if ((*p_sig)->info.si_signo != 0)
2326 ptrace (PTRACE_SETSIGINFO, lwpid_of (thread), (PTRACE_TYPE_ARG3) 0,
2327 &(*p_sig)->info);
2328 free (*p_sig);
2329 *p_sig = NULL;
2330
2331 if (debug_threads)
2332 debug_printf ("Reporting deferred signal %d for LWP %ld.\n",
2333 WSTOPSIG (*wstat), lwpid_of (thread));
2334
2335 if (debug_threads)
2336 {
2337 struct pending_signals *sig;
2338
2339 for (sig = lwp->pending_signals_to_report;
2340 sig != NULL;
2341 sig = sig->prev)
2342 debug_printf (" Still queued %d\n",
2343 sig->signal);
2344
2345 debug_printf (" (no more queued signals)\n");
2346 }
2347
2348 return 1;
2349 }
2350
2351 return 0;
2352 }
2353
2354 /* Fetch the possibly triggered data watchpoint info and store it in
2355 CHILD.
2356
2357 On some archs, like x86, that use debug registers to set
2358 watchpoints, it's possible that the way to know which watched
2359 address trapped, is to check the register that is used to select
2360 which address to watch. Problem is, between setting the watchpoint
2361 and reading back which data address trapped, the user may change
2362 the set of watchpoints, and, as a consequence, GDB changes the
2363 debug registers in the inferior. To avoid reading back a stale
2364 stopped-data-address when that happens, we cache in LP the fact
2365 that a watchpoint trapped, and the corresponding data address, as
2366 soon as we see CHILD stop with a SIGTRAP. If GDB changes the debug
2367 registers meanwhile, we have the cached data we can rely on. */
2368
2369 static int
2370 check_stopped_by_watchpoint (struct lwp_info *child)
2371 {
2372 if (the_low_target.stopped_by_watchpoint != NULL)
2373 {
2374 struct thread_info *saved_thread;
2375
2376 saved_thread = current_thread;
2377 current_thread = get_lwp_thread (child);
2378
2379 if (the_low_target.stopped_by_watchpoint ())
2380 {
2381 child->stop_reason = TARGET_STOPPED_BY_WATCHPOINT;
2382
2383 if (the_low_target.stopped_data_address != NULL)
2384 child->stopped_data_address
2385 = the_low_target.stopped_data_address ();
2386 else
2387 child->stopped_data_address = 0;
2388 }
2389
2390 current_thread = saved_thread;
2391 }
2392
2393 return child->stop_reason == TARGET_STOPPED_BY_WATCHPOINT;
2394 }
2395
2396 /* Return the ptrace options that we want to try to enable. */
2397
2398 static int
2399 linux_low_ptrace_options (int attached)
2400 {
2401 int options = 0;
2402
2403 if (!attached)
2404 options |= PTRACE_O_EXITKILL;
2405
2406 if (report_fork_events)
2407 options |= PTRACE_O_TRACEFORK;
2408
2409 if (report_vfork_events)
2410 options |= (PTRACE_O_TRACEVFORK | PTRACE_O_TRACEVFORKDONE);
2411
2412 if (report_exec_events)
2413 options |= PTRACE_O_TRACEEXEC;
2414
2415 options |= PTRACE_O_TRACESYSGOOD;
2416
2417 return options;
2418 }
2419
2420 /* Do low-level handling of the event, and check if we should go on
2421 and pass it to caller code. Return the affected lwp if we are, or
2422 NULL otherwise. */
2423
2424 static struct lwp_info *
2425 linux_low_filter_event (int lwpid, int wstat)
2426 {
2427 struct lwp_info *child;
2428 struct thread_info *thread;
2429 int have_stop_pc = 0;
2430
2431 child = find_lwp_pid (pid_to_ptid (lwpid));
2432
2433 /* Check for stop events reported by a process we didn't already
2434 know about - anything not already in our LWP list.
2435
2436 If we're expecting to receive stopped processes after
2437 fork, vfork, and clone events, then we'll just add the
2438 new one to our list and go back to waiting for the event
2439 to be reported - the stopped process might be returned
2440 from waitpid before or after the event is.
2441
2442 But note the case of a non-leader thread exec'ing after the
2443 leader having exited, and gone from our lists (because
2444 check_zombie_leaders deleted it). The non-leader thread
2445 changes its tid to the tgid. */
2446
2447 if (WIFSTOPPED (wstat) && child == NULL && WSTOPSIG (wstat) == SIGTRAP
2448 && linux_ptrace_get_extended_event (wstat) == PTRACE_EVENT_EXEC)
2449 {
2450 ptid_t child_ptid;
2451
2452 /* A multi-thread exec after we had seen the leader exiting. */
2453 if (debug_threads)
2454 {
2455 debug_printf ("LLW: Re-adding thread group leader LWP %d"
2456 "after exec.\n", lwpid);
2457 }
2458
2459 child_ptid = ptid_build (lwpid, lwpid, 0);
2460 child = add_lwp (child_ptid);
2461 child->stopped = 1;
2462 current_thread = child->thread;
2463 }
2464
2465 /* If we didn't find a process, one of two things presumably happened:
2466 - A process we started and then detached from has exited. Ignore it.
2467 - A process we are controlling has forked and the new child's stop
2468 was reported to us by the kernel. Save its PID. */
2469 if (child == NULL && WIFSTOPPED (wstat))
2470 {
2471 add_to_pid_list (&stopped_pids, lwpid, wstat);
2472 return NULL;
2473 }
2474 else if (child == NULL)
2475 return NULL;
2476
2477 thread = get_lwp_thread (child);
2478
2479 child->stopped = 1;
2480
2481 child->last_status = wstat;
2482
2483 /* Check if the thread has exited. */
2484 if ((WIFEXITED (wstat) || WIFSIGNALED (wstat)))
2485 {
2486 if (debug_threads)
2487 debug_printf ("LLFE: %d exited.\n", lwpid);
2488
2489 if (finish_step_over (child))
2490 {
2491 /* Unsuspend all other LWPs, and set them back running again. */
2492 unsuspend_all_lwps (child);
2493 }
2494
2495 /* If there is at least one more LWP, then the exit signal was
2496 not the end of the debugged application and should be
2497 ignored, unless GDB wants to hear about thread exits. */
2498 if (report_thread_events
2499 || last_thread_of_process_p (pid_of (thread)))
2500 {
2501 /* Since events are serialized to GDB core, and we can't
2502 report this one right now. Leave the status pending for
2503 the next time we're able to report it. */
2504 mark_lwp_dead (child, wstat);
2505 return child;
2506 }
2507 else
2508 {
2509 delete_lwp (child);
2510 return NULL;
2511 }
2512 }
2513
2514 gdb_assert (WIFSTOPPED (wstat));
2515
2516 if (WIFSTOPPED (wstat))
2517 {
2518 struct process_info *proc;
2519
2520 /* Architecture-specific setup after inferior is running. */
2521 proc = find_process_pid (pid_of (thread));
2522 if (proc->tdesc == NULL)
2523 {
2524 if (proc->attached)
2525 {
2526 /* This needs to happen after we have attached to the
2527 inferior and it is stopped for the first time, but
2528 before we access any inferior registers. */
2529 linux_arch_setup_thread (thread);
2530 }
2531 else
2532 {
2533 /* The process is started, but GDBserver will do
2534 architecture-specific setup after the program stops at
2535 the first instruction. */
2536 child->status_pending_p = 1;
2537 child->status_pending = wstat;
2538 return child;
2539 }
2540 }
2541 }
2542
2543 if (WIFSTOPPED (wstat) && child->must_set_ptrace_flags)
2544 {
2545 struct process_info *proc = find_process_pid (pid_of (thread));
2546 int options = linux_low_ptrace_options (proc->attached);
2547
2548 linux_enable_event_reporting (lwpid, options);
2549 child->must_set_ptrace_flags = 0;
2550 }
2551
2552 /* Always update syscall_state, even if it will be filtered later. */
2553 if (WIFSTOPPED (wstat) && WSTOPSIG (wstat) == SYSCALL_SIGTRAP)
2554 {
2555 child->syscall_state
2556 = (child->syscall_state == TARGET_WAITKIND_SYSCALL_ENTRY
2557 ? TARGET_WAITKIND_SYSCALL_RETURN
2558 : TARGET_WAITKIND_SYSCALL_ENTRY);
2559 }
2560 else
2561 {
2562 /* Almost all other ptrace-stops are known to be outside of system
2563 calls, with further exceptions in handle_extended_wait. */
2564 child->syscall_state = TARGET_WAITKIND_IGNORE;
2565 }
2566
2567 /* Be careful to not overwrite stop_pc until save_stop_reason is
2568 called. */
2569 if (WIFSTOPPED (wstat) && WSTOPSIG (wstat) == SIGTRAP
2570 && linux_is_extended_waitstatus (wstat))
2571 {
2572 child->stop_pc = get_pc (child);
2573 if (handle_extended_wait (&child, wstat))
2574 {
2575 /* The event has been handled, so just return without
2576 reporting it. */
2577 return NULL;
2578 }
2579 }
2580
2581 if (linux_wstatus_maybe_breakpoint (wstat))
2582 {
2583 if (save_stop_reason (child))
2584 have_stop_pc = 1;
2585 }
2586
2587 if (!have_stop_pc)
2588 child->stop_pc = get_pc (child);
2589
2590 if (WIFSTOPPED (wstat) && WSTOPSIG (wstat) == SIGSTOP
2591 && child->stop_expected)
2592 {
2593 if (debug_threads)
2594 debug_printf ("Expected stop.\n");
2595 child->stop_expected = 0;
2596
2597 if (thread->last_resume_kind == resume_stop)
2598 {
2599 /* We want to report the stop to the core. Treat the
2600 SIGSTOP as a normal event. */
2601 if (debug_threads)
2602 debug_printf ("LLW: resume_stop SIGSTOP caught for %s.\n",
2603 target_pid_to_str (ptid_of (thread)));
2604 }
2605 else if (stopping_threads != NOT_STOPPING_THREADS)
2606 {
2607 /* Stopping threads. We don't want this SIGSTOP to end up
2608 pending. */
2609 if (debug_threads)
2610 debug_printf ("LLW: SIGSTOP caught for %s "
2611 "while stopping threads.\n",
2612 target_pid_to_str (ptid_of (thread)));
2613 return NULL;
2614 }
2615 else
2616 {
2617 /* This is a delayed SIGSTOP. Filter out the event. */
2618 if (debug_threads)
2619 debug_printf ("LLW: %s %s, 0, 0 (discard delayed SIGSTOP)\n",
2620 child->stepping ? "step" : "continue",
2621 target_pid_to_str (ptid_of (thread)));
2622
2623 linux_resume_one_lwp (child, child->stepping, 0, NULL);
2624 return NULL;
2625 }
2626 }
2627
2628 child->status_pending_p = 1;
2629 child->status_pending = wstat;
2630 return child;
2631 }
2632
2633 /* Return true if THREAD is doing hardware single step. */
2634
2635 static int
2636 maybe_hw_step (struct thread_info *thread)
2637 {
2638 if (can_hardware_single_step ())
2639 return 1;
2640 else
2641 {
2642 /* GDBserver must insert single-step breakpoint for software
2643 single step. */
2644 gdb_assert (has_single_step_breakpoints (thread));
2645 return 0;
2646 }
2647 }
2648
2649 /* Resume LWPs that are currently stopped without any pending status
2650 to report, but are resumed from the core's perspective. */
2651
2652 static void
2653 resume_stopped_resumed_lwps (thread_info *thread)
2654 {
2655 struct lwp_info *lp = get_thread_lwp (thread);
2656
2657 if (lp->stopped
2658 && !lp->suspended
2659 && !lp->status_pending_p
2660 && thread->last_status.kind == TARGET_WAITKIND_IGNORE)
2661 {
2662 int step = 0;
2663
2664 if (thread->last_resume_kind == resume_step)
2665 step = maybe_hw_step (thread);
2666
2667 if (debug_threads)
2668 debug_printf ("RSRL: resuming stopped-resumed LWP %s at %s: step=%d\n",
2669 target_pid_to_str (ptid_of (thread)),
2670 paddress (lp->stop_pc),
2671 step);
2672
2673 linux_resume_one_lwp (lp, step, GDB_SIGNAL_0, NULL);
2674 }
2675 }
2676
2677 /* Wait for an event from child(ren) WAIT_PTID, and return any that
2678 match FILTER_PTID (leaving others pending). The PTIDs can be:
2679 minus_one_ptid, to specify any child; a pid PTID, specifying all
2680 lwps of a thread group; or a PTID representing a single lwp. Store
2681 the stop status through the status pointer WSTAT. OPTIONS is
2682 passed to the waitpid call. Return 0 if no event was found and
2683 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
2684 was found. Return the PID of the stopped child otherwise. */
2685
2686 static int
2687 linux_wait_for_event_filtered (ptid_t wait_ptid, ptid_t filter_ptid,
2688 int *wstatp, int options)
2689 {
2690 struct thread_info *event_thread;
2691 struct lwp_info *event_child, *requested_child;
2692 sigset_t block_mask, prev_mask;
2693
2694 retry:
2695 /* N.B. event_thread points to the thread_info struct that contains
2696 event_child. Keep them in sync. */
2697 event_thread = NULL;
2698 event_child = NULL;
2699 requested_child = NULL;
2700
2701 /* Check for a lwp with a pending status. */
2702
2703 if (ptid_equal (filter_ptid, minus_one_ptid) || ptid_is_pid (filter_ptid))
2704 {
2705 event_thread = (struct thread_info *)
2706 find_inferior_in_random (&all_threads, status_pending_p_callback,
2707 &filter_ptid);
2708 if (event_thread != NULL)
2709 event_child = get_thread_lwp (event_thread);
2710 if (debug_threads && event_thread)
2711 debug_printf ("Got a pending child %ld\n", lwpid_of (event_thread));
2712 }
2713 else if (!ptid_equal (filter_ptid, null_ptid))
2714 {
2715 requested_child = find_lwp_pid (filter_ptid);
2716
2717 if (stopping_threads == NOT_STOPPING_THREADS
2718 && requested_child->status_pending_p
2719 && (requested_child->collecting_fast_tracepoint
2720 != fast_tpoint_collect_result::not_collecting))
2721 {
2722 enqueue_one_deferred_signal (requested_child,
2723 &requested_child->status_pending);
2724 requested_child->status_pending_p = 0;
2725 requested_child->status_pending = 0;
2726 linux_resume_one_lwp (requested_child, 0, 0, NULL);
2727 }
2728
2729 if (requested_child->suspended
2730 && requested_child->status_pending_p)
2731 {
2732 internal_error (__FILE__, __LINE__,
2733 "requesting an event out of a"
2734 " suspended child?");
2735 }
2736
2737 if (requested_child->status_pending_p)
2738 {
2739 event_child = requested_child;
2740 event_thread = get_lwp_thread (event_child);
2741 }
2742 }
2743
2744 if (event_child != NULL)
2745 {
2746 if (debug_threads)
2747 debug_printf ("Got an event from pending child %ld (%04x)\n",
2748 lwpid_of (event_thread), event_child->status_pending);
2749 *wstatp = event_child->status_pending;
2750 event_child->status_pending_p = 0;
2751 event_child->status_pending = 0;
2752 current_thread = event_thread;
2753 return lwpid_of (event_thread);
2754 }
2755
2756 /* But if we don't find a pending event, we'll have to wait.
2757
2758 We only enter this loop if no process has a pending wait status.
2759 Thus any action taken in response to a wait status inside this
2760 loop is responding as soon as we detect the status, not after any
2761 pending events. */
2762
2763 /* Make sure SIGCHLD is blocked until the sigsuspend below. Block
2764 all signals while here. */
2765 sigfillset (&block_mask);
2766 sigprocmask (SIG_BLOCK, &block_mask, &prev_mask);
2767
2768 /* Always pull all events out of the kernel. We'll randomly select
2769 an event LWP out of all that have events, to prevent
2770 starvation. */
2771 while (event_child == NULL)
2772 {
2773 pid_t ret = 0;
2774
2775 /* Always use -1 and WNOHANG, due to couple of a kernel/ptrace
2776 quirks:
2777
2778 - If the thread group leader exits while other threads in the
2779 thread group still exist, waitpid(TGID, ...) hangs. That
2780 waitpid won't return an exit status until the other threads
2781 in the group are reaped.
2782
2783 - When a non-leader thread execs, that thread just vanishes
2784 without reporting an exit (so we'd hang if we waited for it
2785 explicitly in that case). The exec event is reported to
2786 the TGID pid. */
2787 errno = 0;
2788 ret = my_waitpid (-1, wstatp, options | WNOHANG);
2789
2790 if (debug_threads)
2791 debug_printf ("LWFE: waitpid(-1, ...) returned %d, %s\n",
2792 ret, errno ? strerror (errno) : "ERRNO-OK");
2793
2794 if (ret > 0)
2795 {
2796 if (debug_threads)
2797 {
2798 debug_printf ("LLW: waitpid %ld received %s\n",
2799 (long) ret, status_to_str (*wstatp));
2800 }
2801
2802 /* Filter all events. IOW, leave all events pending. We'll
2803 randomly select an event LWP out of all that have events
2804 below. */
2805 linux_low_filter_event (ret, *wstatp);
2806 /* Retry until nothing comes out of waitpid. A single
2807 SIGCHLD can indicate more than one child stopped. */
2808 continue;
2809 }
2810
2811 /* Now that we've pulled all events out of the kernel, resume
2812 LWPs that don't have an interesting event to report. */
2813 if (stopping_threads == NOT_STOPPING_THREADS)
2814 for_each_inferior (&all_threads, resume_stopped_resumed_lwps);
2815
2816 /* ... and find an LWP with a status to report to the core, if
2817 any. */
2818 event_thread = (struct thread_info *)
2819 find_inferior_in_random (&all_threads, status_pending_p_callback,
2820 &filter_ptid);
2821 if (event_thread != NULL)
2822 {
2823 event_child = get_thread_lwp (event_thread);
2824 *wstatp = event_child->status_pending;
2825 event_child->status_pending_p = 0;
2826 event_child->status_pending = 0;
2827 break;
2828 }
2829
2830 /* Check for zombie thread group leaders. Those can't be reaped
2831 until all other threads in the thread group are. */
2832 check_zombie_leaders ();
2833
2834 /* If there are no resumed children left in the set of LWPs we
2835 want to wait for, bail. We can't just block in
2836 waitpid/sigsuspend, because lwps might have been left stopped
2837 in trace-stop state, and we'd be stuck forever waiting for
2838 their status to change (which would only happen if we resumed
2839 them). Even if WNOHANG is set, this return code is preferred
2840 over 0 (below), as it is more detailed. */
2841 if ((find_inferior (&all_threads,
2842 not_stopped_callback,
2843 &wait_ptid) == NULL))
2844 {
2845 if (debug_threads)
2846 debug_printf ("LLW: exit (no unwaited-for LWP)\n");
2847 sigprocmask (SIG_SETMASK, &prev_mask, NULL);
2848 return -1;
2849 }
2850
2851 /* No interesting event to report to the caller. */
2852 if ((options & WNOHANG))
2853 {
2854 if (debug_threads)
2855 debug_printf ("WNOHANG set, no event found\n");
2856
2857 sigprocmask (SIG_SETMASK, &prev_mask, NULL);
2858 return 0;
2859 }
2860
2861 /* Block until we get an event reported with SIGCHLD. */
2862 if (debug_threads)
2863 debug_printf ("sigsuspend'ing\n");
2864
2865 sigsuspend (&prev_mask);
2866 sigprocmask (SIG_SETMASK, &prev_mask, NULL);
2867 goto retry;
2868 }
2869
2870 sigprocmask (SIG_SETMASK, &prev_mask, NULL);
2871
2872 current_thread = event_thread;
2873
2874 return lwpid_of (event_thread);
2875 }
2876
2877 /* Wait for an event from child(ren) PTID. PTIDs can be:
2878 minus_one_ptid, to specify any child; a pid PTID, specifying all
2879 lwps of a thread group; or a PTID representing a single lwp. Store
2880 the stop status through the status pointer WSTAT. OPTIONS is
2881 passed to the waitpid call. Return 0 if no event was found and
2882 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
2883 was found. Return the PID of the stopped child otherwise. */
2884
2885 static int
2886 linux_wait_for_event (ptid_t ptid, int *wstatp, int options)
2887 {
2888 return linux_wait_for_event_filtered (ptid, ptid, wstatp, options);
2889 }
2890
2891 /* Count the LWP's that have had events. */
2892
2893 static int
2894 count_events_callback (thread_info *thread, void *data)
2895 {
2896 struct lwp_info *lp = get_thread_lwp (thread);
2897 int *count = (int *) data;
2898
2899 gdb_assert (count != NULL);
2900
2901 /* Count only resumed LWPs that have an event pending. */
2902 if (thread->last_status.kind == TARGET_WAITKIND_IGNORE
2903 && lp->status_pending_p)
2904 (*count)++;
2905
2906 return 0;
2907 }
2908
2909 /* Select the LWP (if any) that is currently being single-stepped. */
2910
2911 static int
2912 select_singlestep_lwp_callback (thread_info *thread, void *data)
2913 {
2914 struct lwp_info *lp = get_thread_lwp (thread);
2915
2916 if (thread->last_status.kind == TARGET_WAITKIND_IGNORE
2917 && thread->last_resume_kind == resume_step
2918 && lp->status_pending_p)
2919 return 1;
2920 else
2921 return 0;
2922 }
2923
2924 /* Select the Nth LWP that has had an event. */
2925
2926 static int
2927 select_event_lwp_callback (thread_info *thread, void *data)
2928 {
2929 struct lwp_info *lp = get_thread_lwp (thread);
2930 int *selector = (int *) data;
2931
2932 gdb_assert (selector != NULL);
2933
2934 /* Select only resumed LWPs that have an event pending. */
2935 if (thread->last_status.kind == TARGET_WAITKIND_IGNORE
2936 && lp->status_pending_p)
2937 if ((*selector)-- == 0)
2938 return 1;
2939
2940 return 0;
2941 }
2942
2943 /* Select one LWP out of those that have events pending. */
2944
2945 static void
2946 select_event_lwp (struct lwp_info **orig_lp)
2947 {
2948 int num_events = 0;
2949 int random_selector;
2950 struct thread_info *event_thread = NULL;
2951
2952 /* In all-stop, give preference to the LWP that is being
2953 single-stepped. There will be at most one, and it's the LWP that
2954 the core is most interested in. If we didn't do this, then we'd
2955 have to handle pending step SIGTRAPs somehow in case the core
2956 later continues the previously-stepped thread, otherwise we'd
2957 report the pending SIGTRAP, and the core, not having stepped the
2958 thread, wouldn't understand what the trap was for, and therefore
2959 would report it to the user as a random signal. */
2960 if (!non_stop)
2961 {
2962 event_thread
2963 = (struct thread_info *) find_inferior (&all_threads,
2964 select_singlestep_lwp_callback,
2965 NULL);
2966 if (event_thread != NULL)
2967 {
2968 if (debug_threads)
2969 debug_printf ("SEL: Select single-step %s\n",
2970 target_pid_to_str (ptid_of (event_thread)));
2971 }
2972 }
2973 if (event_thread == NULL)
2974 {
2975 /* No single-stepping LWP. Select one at random, out of those
2976 which have had events. */
2977
2978 /* First see how many events we have. */
2979 find_inferior (&all_threads, count_events_callback, &num_events);
2980 gdb_assert (num_events > 0);
2981
2982 /* Now randomly pick a LWP out of those that have had
2983 events. */
2984 random_selector = (int)
2985 ((num_events * (double) rand ()) / (RAND_MAX + 1.0));
2986
2987 if (debug_threads && num_events > 1)
2988 debug_printf ("SEL: Found %d SIGTRAP events, selecting #%d\n",
2989 num_events, random_selector);
2990
2991 event_thread
2992 = (struct thread_info *) find_inferior (&all_threads,
2993 select_event_lwp_callback,
2994 &random_selector);
2995 }
2996
2997 if (event_thread != NULL)
2998 {
2999 struct lwp_info *event_lp = get_thread_lwp (event_thread);
3000
3001 /* Switch the event LWP. */
3002 *orig_lp = event_lp;
3003 }
3004 }
3005
3006 /* Decrement the suspend count of an LWP. */
3007
3008 static int
3009 unsuspend_one_lwp (thread_info *thread, void *except)
3010 {
3011 struct lwp_info *lwp = get_thread_lwp (thread);
3012
3013 /* Ignore EXCEPT. */
3014 if (lwp == except)
3015 return 0;
3016
3017 lwp_suspended_decr (lwp);
3018 return 0;
3019 }
3020
3021 /* Decrement the suspend count of all LWPs, except EXCEPT, if non
3022 NULL. */
3023
3024 static void
3025 unsuspend_all_lwps (struct lwp_info *except)
3026 {
3027 find_inferior (&all_threads, unsuspend_one_lwp, except);
3028 }
3029
3030 static void move_out_of_jump_pad_callback (thread_info *thread);
3031 static int stuck_in_jump_pad_callback (thread_info *thread, void *data);
3032 static int lwp_running (thread_info *thread, void *data);
3033 static ptid_t linux_wait_1 (ptid_t ptid,
3034 struct target_waitstatus *ourstatus,
3035 int target_options);
3036
3037 /* Stabilize threads (move out of jump pads).
3038
3039 If a thread is midway collecting a fast tracepoint, we need to
3040 finish the collection and move it out of the jump pad before
3041 reporting the signal.
3042
3043 This avoids recursion while collecting (when a signal arrives
3044 midway, and the signal handler itself collects), which would trash
3045 the trace buffer. In case the user set a breakpoint in a signal
3046 handler, this avoids the backtrace showing the jump pad, etc..
3047 Most importantly, there are certain things we can't do safely if
3048 threads are stopped in a jump pad (or in its callee's). For
3049 example:
3050
3051 - starting a new trace run. A thread still collecting the
3052 previous run, could trash the trace buffer when resumed. The trace
3053 buffer control structures would have been reset but the thread had
3054 no way to tell. The thread could even midway memcpy'ing to the
3055 buffer, which would mean that when resumed, it would clobber the
3056 trace buffer that had been set for a new run.
3057
3058 - we can't rewrite/reuse the jump pads for new tracepoints
3059 safely. Say you do tstart while a thread is stopped midway while
3060 collecting. When the thread is later resumed, it finishes the
3061 collection, and returns to the jump pad, to execute the original
3062 instruction that was under the tracepoint jump at the time the
3063 older run had been started. If the jump pad had been rewritten
3064 since for something else in the new run, the thread would now
3065 execute the wrong / random instructions. */
3066
3067 static void
3068 linux_stabilize_threads (void)
3069 {
3070 struct thread_info *saved_thread;
3071 struct thread_info *thread_stuck;
3072
3073 thread_stuck
3074 = (struct thread_info *) find_inferior (&all_threads,
3075 stuck_in_jump_pad_callback,
3076 NULL);
3077 if (thread_stuck != NULL)
3078 {
3079 if (debug_threads)
3080 debug_printf ("can't stabilize, LWP %ld is stuck in jump pad\n",
3081 lwpid_of (thread_stuck));
3082 return;
3083 }
3084
3085 saved_thread = current_thread;
3086
3087 stabilizing_threads = 1;
3088
3089 /* Kick 'em all. */
3090 for_each_inferior (&all_threads, move_out_of_jump_pad_callback);
3091
3092 /* Loop until all are stopped out of the jump pads. */
3093 while (find_inferior (&all_threads, lwp_running, NULL) != NULL)
3094 {
3095 struct target_waitstatus ourstatus;
3096 struct lwp_info *lwp;
3097 int wstat;
3098
3099 /* Note that we go through the full wait even loop. While
3100 moving threads out of jump pad, we need to be able to step
3101 over internal breakpoints and such. */
3102 linux_wait_1 (minus_one_ptid, &ourstatus, 0);
3103
3104 if (ourstatus.kind == TARGET_WAITKIND_STOPPED)
3105 {
3106 lwp = get_thread_lwp (current_thread);
3107
3108 /* Lock it. */
3109 lwp_suspended_inc (lwp);
3110
3111 if (ourstatus.value.sig != GDB_SIGNAL_0
3112 || current_thread->last_resume_kind == resume_stop)
3113 {
3114 wstat = W_STOPCODE (gdb_signal_to_host (ourstatus.value.sig));
3115 enqueue_one_deferred_signal (lwp, &wstat);
3116 }
3117 }
3118 }
3119
3120 unsuspend_all_lwps (NULL);
3121
3122 stabilizing_threads = 0;
3123
3124 current_thread = saved_thread;
3125
3126 if (debug_threads)
3127 {
3128 thread_stuck
3129 = (struct thread_info *) find_inferior (&all_threads,
3130 stuck_in_jump_pad_callback,
3131 NULL);
3132 if (thread_stuck != NULL)
3133 debug_printf ("couldn't stabilize, LWP %ld got stuck in jump pad\n",
3134 lwpid_of (thread_stuck));
3135 }
3136 }
3137
3138 /* Convenience function that is called when the kernel reports an
3139 event that is not passed out to GDB. */
3140
3141 static ptid_t
3142 ignore_event (struct target_waitstatus *ourstatus)
3143 {
3144 /* If we got an event, there may still be others, as a single
3145 SIGCHLD can indicate more than one child stopped. This forces
3146 another target_wait call. */
3147 async_file_mark ();
3148
3149 ourstatus->kind = TARGET_WAITKIND_IGNORE;
3150 return null_ptid;
3151 }
3152
3153 /* Convenience function that is called when the kernel reports an exit
3154 event. This decides whether to report the event to GDB as a
3155 process exit event, a thread exit event, or to suppress the
3156 event. */
3157
3158 static ptid_t
3159 filter_exit_event (struct lwp_info *event_child,
3160 struct target_waitstatus *ourstatus)
3161 {
3162 struct thread_info *thread = get_lwp_thread (event_child);
3163 ptid_t ptid = ptid_of (thread);
3164
3165 if (!last_thread_of_process_p (pid_of (thread)))
3166 {
3167 if (report_thread_events)
3168 ourstatus->kind = TARGET_WAITKIND_THREAD_EXITED;
3169 else
3170 ourstatus->kind = TARGET_WAITKIND_IGNORE;
3171
3172 delete_lwp (event_child);
3173 }
3174 return ptid;
3175 }
3176
3177 /* Returns 1 if GDB is interested in any event_child syscalls. */
3178
3179 static int
3180 gdb_catching_syscalls_p (struct lwp_info *event_child)
3181 {
3182 struct thread_info *thread = get_lwp_thread (event_child);
3183 struct process_info *proc = get_thread_process (thread);
3184
3185 return !VEC_empty (int, proc->syscalls_to_catch);
3186 }
3187
3188 /* Returns 1 if GDB is interested in the event_child syscall.
3189 Only to be called when stopped reason is SYSCALL_SIGTRAP. */
3190
3191 static int
3192 gdb_catch_this_syscall_p (struct lwp_info *event_child)
3193 {
3194 int i, iter;
3195 int sysno;
3196 struct thread_info *thread = get_lwp_thread (event_child);
3197 struct process_info *proc = get_thread_process (thread);
3198
3199 if (VEC_empty (int, proc->syscalls_to_catch))
3200 return 0;
3201
3202 if (VEC_index (int, proc->syscalls_to_catch, 0) == ANY_SYSCALL)
3203 return 1;
3204
3205 get_syscall_trapinfo (event_child, &sysno);
3206 for (i = 0;
3207 VEC_iterate (int, proc->syscalls_to_catch, i, iter);
3208 i++)
3209 if (iter == sysno)
3210 return 1;
3211
3212 return 0;
3213 }
3214
3215 /* Wait for process, returns status. */
3216
3217 static ptid_t
3218 linux_wait_1 (ptid_t ptid,
3219 struct target_waitstatus *ourstatus, int target_options)
3220 {
3221 int w;
3222 struct lwp_info *event_child;
3223 int options;
3224 int pid;
3225 int step_over_finished;
3226 int bp_explains_trap;
3227 int maybe_internal_trap;
3228 int report_to_gdb;
3229 int trace_event;
3230 int in_step_range;
3231 int any_resumed;
3232
3233 if (debug_threads)
3234 {
3235 debug_enter ();
3236 debug_printf ("linux_wait_1: [%s]\n", target_pid_to_str (ptid));
3237 }
3238
3239 /* Translate generic target options into linux options. */
3240 options = __WALL;
3241 if (target_options & TARGET_WNOHANG)
3242 options |= WNOHANG;
3243
3244 bp_explains_trap = 0;
3245 trace_event = 0;
3246 in_step_range = 0;
3247 ourstatus->kind = TARGET_WAITKIND_IGNORE;
3248
3249 /* Find a resumed LWP, if any. */
3250 if (find_inferior (&all_threads,
3251 status_pending_p_callback,
3252 &minus_one_ptid) != NULL)
3253 any_resumed = 1;
3254 else if ((find_inferior (&all_threads,
3255 not_stopped_callback,
3256 &minus_one_ptid) != NULL))
3257 any_resumed = 1;
3258 else
3259 any_resumed = 0;
3260
3261 if (ptid_equal (step_over_bkpt, null_ptid))
3262 pid = linux_wait_for_event (ptid, &w, options);
3263 else
3264 {
3265 if (debug_threads)
3266 debug_printf ("step_over_bkpt set [%s], doing a blocking wait\n",
3267 target_pid_to_str (step_over_bkpt));
3268 pid = linux_wait_for_event (step_over_bkpt, &w, options & ~WNOHANG);
3269 }
3270
3271 if (pid == 0 || (pid == -1 && !any_resumed))
3272 {
3273 gdb_assert (target_options & TARGET_WNOHANG);
3274
3275 if (debug_threads)
3276 {
3277 debug_printf ("linux_wait_1 ret = null_ptid, "
3278 "TARGET_WAITKIND_IGNORE\n");
3279 debug_exit ();
3280 }
3281
3282 ourstatus->kind = TARGET_WAITKIND_IGNORE;
3283 return null_ptid;
3284 }
3285 else if (pid == -1)
3286 {
3287 if (debug_threads)
3288 {
3289 debug_printf ("linux_wait_1 ret = null_ptid, "
3290 "TARGET_WAITKIND_NO_RESUMED\n");
3291 debug_exit ();
3292 }
3293
3294 ourstatus->kind = TARGET_WAITKIND_NO_RESUMED;
3295 return null_ptid;
3296 }
3297
3298 event_child = get_thread_lwp (current_thread);
3299
3300 /* linux_wait_for_event only returns an exit status for the last
3301 child of a process. Report it. */
3302 if (WIFEXITED (w) || WIFSIGNALED (w))
3303 {
3304 if (WIFEXITED (w))
3305 {
3306 ourstatus->kind = TARGET_WAITKIND_EXITED;
3307 ourstatus->value.integer = WEXITSTATUS (w);
3308
3309 if (debug_threads)
3310 {
3311 debug_printf ("linux_wait_1 ret = %s, exited with "
3312 "retcode %d\n",
3313 target_pid_to_str (ptid_of (current_thread)),
3314 WEXITSTATUS (w));
3315 debug_exit ();
3316 }
3317 }
3318 else
3319 {
3320 ourstatus->kind = TARGET_WAITKIND_SIGNALLED;
3321 ourstatus->value.sig = gdb_signal_from_host (WTERMSIG (w));
3322
3323 if (debug_threads)
3324 {
3325 debug_printf ("linux_wait_1 ret = %s, terminated with "
3326 "signal %d\n",
3327 target_pid_to_str (ptid_of (current_thread)),
3328 WTERMSIG (w));
3329 debug_exit ();
3330 }
3331 }
3332
3333 if (ourstatus->kind == TARGET_WAITKIND_EXITED)
3334 return filter_exit_event (event_child, ourstatus);
3335
3336 return ptid_of (current_thread);
3337 }
3338
3339 /* If step-over executes a breakpoint instruction, in the case of a
3340 hardware single step it means a gdb/gdbserver breakpoint had been
3341 planted on top of a permanent breakpoint, in the case of a software
3342 single step it may just mean that gdbserver hit the reinsert breakpoint.
3343 The PC has been adjusted by save_stop_reason to point at
3344 the breakpoint address.
3345 So in the case of the hardware single step advance the PC manually
3346 past the breakpoint and in the case of software single step advance only
3347 if it's not the single_step_breakpoint we are hitting.
3348 This avoids that a program would keep trapping a permanent breakpoint
3349 forever. */
3350 if (!ptid_equal (step_over_bkpt, null_ptid)
3351 && event_child->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT
3352 && (event_child->stepping
3353 || !single_step_breakpoint_inserted_here (event_child->stop_pc)))
3354 {
3355 int increment_pc = 0;
3356 int breakpoint_kind = 0;
3357 CORE_ADDR stop_pc = event_child->stop_pc;
3358
3359 breakpoint_kind =
3360 the_target->breakpoint_kind_from_current_state (&stop_pc);
3361 the_target->sw_breakpoint_from_kind (breakpoint_kind, &increment_pc);
3362
3363 if (debug_threads)
3364 {
3365 debug_printf ("step-over for %s executed software breakpoint\n",
3366 target_pid_to_str (ptid_of (current_thread)));
3367 }
3368
3369 if (increment_pc != 0)
3370 {
3371 struct regcache *regcache
3372 = get_thread_regcache (current_thread, 1);
3373
3374 event_child->stop_pc += increment_pc;
3375 (*the_low_target.set_pc) (regcache, event_child->stop_pc);
3376
3377 if (!(*the_low_target.breakpoint_at) (event_child->stop_pc))
3378 event_child->stop_reason = TARGET_STOPPED_BY_NO_REASON;
3379 }
3380 }
3381
3382 /* If this event was not handled before, and is not a SIGTRAP, we
3383 report it. SIGILL and SIGSEGV are also treated as traps in case
3384 a breakpoint is inserted at the current PC. If this target does
3385 not support internal breakpoints at all, we also report the
3386 SIGTRAP without further processing; it's of no concern to us. */
3387 maybe_internal_trap
3388 = (supports_breakpoints ()
3389 && (WSTOPSIG (w) == SIGTRAP
3390 || ((WSTOPSIG (w) == SIGILL
3391 || WSTOPSIG (w) == SIGSEGV)
3392 && (*the_low_target.breakpoint_at) (event_child->stop_pc))));
3393
3394 if (maybe_internal_trap)
3395 {
3396 /* Handle anything that requires bookkeeping before deciding to
3397 report the event or continue waiting. */
3398
3399 /* First check if we can explain the SIGTRAP with an internal
3400 breakpoint, or if we should possibly report the event to GDB.
3401 Do this before anything that may remove or insert a
3402 breakpoint. */
3403 bp_explains_trap = breakpoint_inserted_here (event_child->stop_pc);
3404
3405 /* We have a SIGTRAP, possibly a step-over dance has just
3406 finished. If so, tweak the state machine accordingly,
3407 reinsert breakpoints and delete any single-step
3408 breakpoints. */
3409 step_over_finished = finish_step_over (event_child);
3410
3411 /* Now invoke the callbacks of any internal breakpoints there. */
3412 check_breakpoints (event_child->stop_pc);
3413
3414 /* Handle tracepoint data collecting. This may overflow the
3415 trace buffer, and cause a tracing stop, removing
3416 breakpoints. */
3417 trace_event = handle_tracepoints (event_child);
3418
3419 if (bp_explains_trap)
3420 {
3421 if (debug_threads)
3422 debug_printf ("Hit a gdbserver breakpoint.\n");
3423 }
3424 }
3425 else
3426 {
3427 /* We have some other signal, possibly a step-over dance was in
3428 progress, and it should be cancelled too. */
3429 step_over_finished = finish_step_over (event_child);
3430 }
3431
3432 /* We have all the data we need. Either report the event to GDB, or
3433 resume threads and keep waiting for more. */
3434
3435 /* If we're collecting a fast tracepoint, finish the collection and
3436 move out of the jump pad before delivering a signal. See
3437 linux_stabilize_threads. */
3438
3439 if (WIFSTOPPED (w)
3440 && WSTOPSIG (w) != SIGTRAP
3441 && supports_fast_tracepoints ()
3442 && agent_loaded_p ())
3443 {
3444 if (debug_threads)
3445 debug_printf ("Got signal %d for LWP %ld. Check if we need "
3446 "to defer or adjust it.\n",
3447 WSTOPSIG (w), lwpid_of (current_thread));
3448
3449 /* Allow debugging the jump pad itself. */
3450 if (current_thread->last_resume_kind != resume_step
3451 && maybe_move_out_of_jump_pad (event_child, &w))
3452 {
3453 enqueue_one_deferred_signal (event_child, &w);
3454
3455 if (debug_threads)
3456 debug_printf ("Signal %d for LWP %ld deferred (in jump pad)\n",
3457 WSTOPSIG (w), lwpid_of (current_thread));
3458
3459 linux_resume_one_lwp (event_child, 0, 0, NULL);
3460
3461 if (debug_threads)
3462 debug_exit ();
3463 return ignore_event (ourstatus);
3464 }
3465 }
3466
3467 if (event_child->collecting_fast_tracepoint
3468 != fast_tpoint_collect_result::not_collecting)
3469 {
3470 if (debug_threads)
3471 debug_printf ("LWP %ld was trying to move out of the jump pad (%d). "
3472 "Check if we're already there.\n",
3473 lwpid_of (current_thread),
3474 (int) event_child->collecting_fast_tracepoint);
3475
3476 trace_event = 1;
3477
3478 event_child->collecting_fast_tracepoint
3479 = linux_fast_tracepoint_collecting (event_child, NULL);
3480
3481 if (event_child->collecting_fast_tracepoint
3482 != fast_tpoint_collect_result::before_insn)
3483 {
3484 /* No longer need this breakpoint. */
3485 if (event_child->exit_jump_pad_bkpt != NULL)
3486 {
3487 if (debug_threads)
3488 debug_printf ("No longer need exit-jump-pad bkpt; removing it."
3489 "stopping all threads momentarily.\n");
3490
3491 /* Other running threads could hit this breakpoint.
3492 We don't handle moribund locations like GDB does,
3493 instead we always pause all threads when removing
3494 breakpoints, so that any step-over or
3495 decr_pc_after_break adjustment is always taken
3496 care of while the breakpoint is still
3497 inserted. */
3498 stop_all_lwps (1, event_child);
3499
3500 delete_breakpoint (event_child->exit_jump_pad_bkpt);
3501 event_child->exit_jump_pad_bkpt = NULL;
3502
3503 unstop_all_lwps (1, event_child);
3504
3505 gdb_assert (event_child->suspended >= 0);
3506 }
3507 }
3508
3509 if (event_child->collecting_fast_tracepoint
3510 == fast_tpoint_collect_result::not_collecting)
3511 {
3512 if (debug_threads)
3513 debug_printf ("fast tracepoint finished "
3514 "collecting successfully.\n");
3515
3516 /* We may have a deferred signal to report. */
3517 if (dequeue_one_deferred_signal (event_child, &w))
3518 {
3519 if (debug_threads)
3520 debug_printf ("dequeued one signal.\n");
3521 }
3522 else
3523 {
3524 if (debug_threads)
3525 debug_printf ("no deferred signals.\n");
3526
3527 if (stabilizing_threads)
3528 {
3529 ourstatus->kind = TARGET_WAITKIND_STOPPED;
3530 ourstatus->value.sig = GDB_SIGNAL_0;
3531
3532 if (debug_threads)
3533 {
3534 debug_printf ("linux_wait_1 ret = %s, stopped "
3535 "while stabilizing threads\n",
3536 target_pid_to_str (ptid_of (current_thread)));
3537 debug_exit ();
3538 }
3539
3540 return ptid_of (current_thread);
3541 }
3542 }
3543 }
3544 }
3545
3546 /* Check whether GDB would be interested in this event. */
3547
3548 /* Check if GDB is interested in this syscall. */
3549 if (WIFSTOPPED (w)
3550 && WSTOPSIG (w) == SYSCALL_SIGTRAP
3551 && !gdb_catch_this_syscall_p (event_child))
3552 {
3553 if (debug_threads)
3554 {
3555 debug_printf ("Ignored syscall for LWP %ld.\n",
3556 lwpid_of (current_thread));
3557 }
3558
3559 linux_resume_one_lwp (event_child, event_child->stepping,
3560 0, NULL);
3561
3562 if (debug_threads)
3563 debug_exit ();
3564 return ignore_event (ourstatus);
3565 }
3566
3567 /* If GDB is not interested in this signal, don't stop other
3568 threads, and don't report it to GDB. Just resume the inferior
3569 right away. We do this for threading-related signals as well as
3570 any that GDB specifically requested we ignore. But never ignore
3571 SIGSTOP if we sent it ourselves, and do not ignore signals when
3572 stepping - they may require special handling to skip the signal
3573 handler. Also never ignore signals that could be caused by a
3574 breakpoint. */
3575 if (WIFSTOPPED (w)
3576 && current_thread->last_resume_kind != resume_step
3577 && (
3578 #if defined (USE_THREAD_DB) && !defined (__ANDROID__)
3579 (current_process ()->priv->thread_db != NULL
3580 && (WSTOPSIG (w) == __SIGRTMIN
3581 || WSTOPSIG (w) == __SIGRTMIN + 1))
3582 ||
3583 #endif
3584 (pass_signals[gdb_signal_from_host (WSTOPSIG (w))]
3585 && !(WSTOPSIG (w) == SIGSTOP
3586 && current_thread->last_resume_kind == resume_stop)
3587 && !linux_wstatus_maybe_breakpoint (w))))
3588 {
3589 siginfo_t info, *info_p;
3590
3591 if (debug_threads)
3592 debug_printf ("Ignored signal %d for LWP %ld.\n",
3593 WSTOPSIG (w), lwpid_of (current_thread));
3594
3595 if (ptrace (PTRACE_GETSIGINFO, lwpid_of (current_thread),
3596 (PTRACE_TYPE_ARG3) 0, &info) == 0)
3597 info_p = &info;
3598 else
3599 info_p = NULL;
3600
3601 if (step_over_finished)
3602 {
3603 /* We cancelled this thread's step-over above. We still
3604 need to unsuspend all other LWPs, and set them back
3605 running again while the signal handler runs. */
3606 unsuspend_all_lwps (event_child);
3607
3608 /* Enqueue the pending signal info so that proceed_all_lwps
3609 doesn't lose it. */
3610 enqueue_pending_signal (event_child, WSTOPSIG (w), info_p);
3611
3612 proceed_all_lwps ();
3613 }
3614 else
3615 {
3616 linux_resume_one_lwp (event_child, event_child->stepping,
3617 WSTOPSIG (w), info_p);
3618 }
3619
3620 if (debug_threads)
3621 debug_exit ();
3622
3623 return ignore_event (ourstatus);
3624 }
3625
3626 /* Note that all addresses are always "out of the step range" when
3627 there's no range to begin with. */
3628 in_step_range = lwp_in_step_range (event_child);
3629
3630 /* If GDB wanted this thread to single step, and the thread is out
3631 of the step range, we always want to report the SIGTRAP, and let
3632 GDB handle it. Watchpoints should always be reported. So should
3633 signals we can't explain. A SIGTRAP we can't explain could be a
3634 GDB breakpoint --- we may or not support Z0 breakpoints. If we
3635 do, we're be able to handle GDB breakpoints on top of internal
3636 breakpoints, by handling the internal breakpoint and still
3637 reporting the event to GDB. If we don't, we're out of luck, GDB
3638 won't see the breakpoint hit. If we see a single-step event but
3639 the thread should be continuing, don't pass the trap to gdb.
3640 That indicates that we had previously finished a single-step but
3641 left the single-step pending -- see
3642 complete_ongoing_step_over. */
3643 report_to_gdb = (!maybe_internal_trap
3644 || (current_thread->last_resume_kind == resume_step
3645 && !in_step_range)
3646 || event_child->stop_reason == TARGET_STOPPED_BY_WATCHPOINT
3647 || (!in_step_range
3648 && !bp_explains_trap
3649 && !trace_event
3650 && !step_over_finished
3651 && !(current_thread->last_resume_kind == resume_continue
3652 && event_child->stop_reason == TARGET_STOPPED_BY_SINGLE_STEP))
3653 || (gdb_breakpoint_here (event_child->stop_pc)
3654 && gdb_condition_true_at_breakpoint (event_child->stop_pc)
3655 && gdb_no_commands_at_breakpoint (event_child->stop_pc))
3656 || event_child->waitstatus.kind != TARGET_WAITKIND_IGNORE);
3657
3658 run_breakpoint_commands (event_child->stop_pc);
3659
3660 /* We found no reason GDB would want us to stop. We either hit one
3661 of our own breakpoints, or finished an internal step GDB
3662 shouldn't know about. */
3663 if (!report_to_gdb)
3664 {
3665 if (debug_threads)
3666 {
3667 if (bp_explains_trap)
3668 debug_printf ("Hit a gdbserver breakpoint.\n");
3669 if (step_over_finished)
3670 debug_printf ("Step-over finished.\n");
3671 if (trace_event)
3672 debug_printf ("Tracepoint event.\n");
3673 if (lwp_in_step_range (event_child))
3674 debug_printf ("Range stepping pc 0x%s [0x%s, 0x%s).\n",
3675 paddress (event_child->stop_pc),
3676 paddress (event_child->step_range_start),
3677 paddress (event_child->step_range_end));
3678 }
3679
3680 /* We're not reporting this breakpoint to GDB, so apply the
3681 decr_pc_after_break adjustment to the inferior's regcache
3682 ourselves. */
3683
3684 if (the_low_target.set_pc != NULL)
3685 {
3686 struct regcache *regcache
3687 = get_thread_regcache (current_thread, 1);
3688 (*the_low_target.set_pc) (regcache, event_child->stop_pc);
3689 }
3690
3691 if (step_over_finished)
3692 {
3693 /* If we have finished stepping over a breakpoint, we've
3694 stopped and suspended all LWPs momentarily except the
3695 stepping one. This is where we resume them all again.
3696 We're going to keep waiting, so use proceed, which
3697 handles stepping over the next breakpoint. */
3698 unsuspend_all_lwps (event_child);
3699 }
3700 else
3701 {
3702 /* Remove the single-step breakpoints if any. Note that
3703 there isn't single-step breakpoint if we finished stepping
3704 over. */
3705 if (can_software_single_step ()
3706 && has_single_step_breakpoints (current_thread))
3707 {
3708 stop_all_lwps (0, event_child);
3709 delete_single_step_breakpoints (current_thread);
3710 unstop_all_lwps (0, event_child);
3711 }
3712 }
3713
3714 if (debug_threads)
3715 debug_printf ("proceeding all threads.\n");
3716 proceed_all_lwps ();
3717
3718 if (debug_threads)
3719 debug_exit ();
3720
3721 return ignore_event (ourstatus);
3722 }
3723
3724 if (debug_threads)
3725 {
3726 if (event_child->waitstatus.kind != TARGET_WAITKIND_IGNORE)
3727 {
3728 std::string str
3729 = target_waitstatus_to_string (&event_child->waitstatus);
3730
3731 debug_printf ("LWP %ld: extended event with waitstatus %s\n",
3732 lwpid_of (get_lwp_thread (event_child)), str.c_str ());
3733 }
3734 if (current_thread->last_resume_kind == resume_step)
3735 {
3736 if (event_child->step_range_start == event_child->step_range_end)
3737 debug_printf ("GDB wanted to single-step, reporting event.\n");
3738 else if (!lwp_in_step_range (event_child))
3739 debug_printf ("Out of step range, reporting event.\n");
3740 }
3741 if (event_child->stop_reason == TARGET_STOPPED_BY_WATCHPOINT)
3742 debug_printf ("Stopped by watchpoint.\n");
3743 else if (gdb_breakpoint_here (event_child->stop_pc))
3744 debug_printf ("Stopped by GDB breakpoint.\n");
3745 if (debug_threads)
3746 debug_printf ("Hit a non-gdbserver trap event.\n");
3747 }
3748
3749 /* Alright, we're going to report a stop. */
3750
3751 /* Remove single-step breakpoints. */
3752 if (can_software_single_step ())
3753 {
3754 /* Remove single-step breakpoints or not. It it is true, stop all
3755 lwps, so that other threads won't hit the breakpoint in the
3756 staled memory. */
3757 int remove_single_step_breakpoints_p = 0;
3758
3759 if (non_stop)
3760 {
3761 remove_single_step_breakpoints_p
3762 = has_single_step_breakpoints (current_thread);
3763 }
3764 else
3765 {
3766 /* In all-stop, a stop reply cancels all previous resume
3767 requests. Delete all single-step breakpoints. */
3768
3769 find_thread ([&] (thread_info *thread) {
3770 if (has_single_step_breakpoints (thread))
3771 {
3772 remove_single_step_breakpoints_p = 1;
3773 return true;
3774 }
3775
3776 return false;
3777 });
3778 }
3779
3780 if (remove_single_step_breakpoints_p)
3781 {
3782 /* If we remove single-step breakpoints from memory, stop all lwps,
3783 so that other threads won't hit the breakpoint in the staled
3784 memory. */
3785 stop_all_lwps (0, event_child);
3786
3787 if (non_stop)
3788 {
3789 gdb_assert (has_single_step_breakpoints (current_thread));
3790 delete_single_step_breakpoints (current_thread);
3791 }
3792 else
3793 {
3794 for_each_thread ([] (thread_info *thread){
3795 if (has_single_step_breakpoints (thread))
3796 delete_single_step_breakpoints (thread);
3797 });
3798 }
3799
3800 unstop_all_lwps (0, event_child);
3801 }
3802 }
3803
3804 if (!stabilizing_threads)
3805 {
3806 /* In all-stop, stop all threads. */
3807 if (!non_stop)
3808 stop_all_lwps (0, NULL);
3809
3810 if (step_over_finished)
3811 {
3812 if (!non_stop)
3813 {
3814 /* If we were doing a step-over, all other threads but
3815 the stepping one had been paused in start_step_over,
3816 with their suspend counts incremented. We don't want
3817 to do a full unstop/unpause, because we're in
3818 all-stop mode (so we want threads stopped), but we
3819 still need to unsuspend the other threads, to
3820 decrement their `suspended' count back. */
3821 unsuspend_all_lwps (event_child);
3822 }
3823 else
3824 {
3825 /* If we just finished a step-over, then all threads had
3826 been momentarily paused. In all-stop, that's fine,
3827 we want threads stopped by now anyway. In non-stop,
3828 we need to re-resume threads that GDB wanted to be
3829 running. */
3830 unstop_all_lwps (1, event_child);
3831 }
3832 }
3833
3834 /* If we're not waiting for a specific LWP, choose an event LWP
3835 from among those that have had events. Giving equal priority
3836 to all LWPs that have had events helps prevent
3837 starvation. */
3838 if (ptid_equal (ptid, minus_one_ptid))
3839 {
3840 event_child->status_pending_p = 1;
3841 event_child->status_pending = w;
3842
3843 select_event_lwp (&event_child);
3844
3845 /* current_thread and event_child must stay in sync. */
3846 current_thread = get_lwp_thread (event_child);
3847
3848 event_child->status_pending_p = 0;
3849 w = event_child->status_pending;
3850 }
3851
3852
3853 /* Stabilize threads (move out of jump pads). */
3854 if (!non_stop)
3855 stabilize_threads ();
3856 }
3857 else
3858 {
3859 /* If we just finished a step-over, then all threads had been
3860 momentarily paused. In all-stop, that's fine, we want
3861 threads stopped by now anyway. In non-stop, we need to
3862 re-resume threads that GDB wanted to be running. */
3863 if (step_over_finished)
3864 unstop_all_lwps (1, event_child);
3865 }
3866
3867 if (event_child->waitstatus.kind != TARGET_WAITKIND_IGNORE)
3868 {
3869 /* If the reported event is an exit, fork, vfork or exec, let
3870 GDB know. */
3871
3872 /* Break the unreported fork relationship chain. */
3873 if (event_child->waitstatus.kind == TARGET_WAITKIND_FORKED
3874 || event_child->waitstatus.kind == TARGET_WAITKIND_VFORKED)
3875 {
3876 event_child->fork_relative->fork_relative = NULL;
3877 event_child->fork_relative = NULL;
3878 }
3879
3880 *ourstatus = event_child->waitstatus;
3881 /* Clear the event lwp's waitstatus since we handled it already. */
3882 event_child->waitstatus.kind = TARGET_WAITKIND_IGNORE;
3883 }
3884 else
3885 ourstatus->kind = TARGET_WAITKIND_STOPPED;
3886
3887 /* Now that we've selected our final event LWP, un-adjust its PC if
3888 it was a software breakpoint, and the client doesn't know we can
3889 adjust the breakpoint ourselves. */
3890 if (event_child->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT
3891 && !swbreak_feature)
3892 {
3893 int decr_pc = the_low_target.decr_pc_after_break;
3894
3895 if (decr_pc != 0)
3896 {
3897 struct regcache *regcache
3898 = get_thread_regcache (current_thread, 1);
3899 (*the_low_target.set_pc) (regcache, event_child->stop_pc + decr_pc);
3900 }
3901 }
3902
3903 if (WSTOPSIG (w) == SYSCALL_SIGTRAP)
3904 {
3905 get_syscall_trapinfo (event_child,
3906 &ourstatus->value.syscall_number);
3907 ourstatus->kind = event_child->syscall_state;
3908 }
3909 else if (current_thread->last_resume_kind == resume_stop
3910 && WSTOPSIG (w) == SIGSTOP)
3911 {
3912 /* A thread that has been requested to stop by GDB with vCont;t,
3913 and it stopped cleanly, so report as SIG0. The use of
3914 SIGSTOP is an implementation detail. */
3915 ourstatus->value.sig = GDB_SIGNAL_0;
3916 }
3917 else if (current_thread->last_resume_kind == resume_stop
3918 && WSTOPSIG (w) != SIGSTOP)
3919 {
3920 /* A thread that has been requested to stop by GDB with vCont;t,
3921 but, it stopped for other reasons. */
3922 ourstatus->value.sig = gdb_signal_from_host (WSTOPSIG (w));
3923 }
3924 else if (ourstatus->kind == TARGET_WAITKIND_STOPPED)
3925 {
3926 ourstatus->value.sig = gdb_signal_from_host (WSTOPSIG (w));
3927 }
3928
3929 gdb_assert (ptid_equal (step_over_bkpt, null_ptid));
3930
3931 if (debug_threads)
3932 {
3933 debug_printf ("linux_wait_1 ret = %s, %d, %d\n",
3934 target_pid_to_str (ptid_of (current_thread)),
3935 ourstatus->kind, ourstatus->value.sig);
3936 debug_exit ();
3937 }
3938
3939 if (ourstatus->kind == TARGET_WAITKIND_EXITED)
3940 return filter_exit_event (event_child, ourstatus);
3941
3942 return ptid_of (current_thread);
3943 }
3944
3945 /* Get rid of any pending event in the pipe. */
3946 static void
3947 async_file_flush (void)
3948 {
3949 int ret;
3950 char buf;
3951
3952 do
3953 ret = read (linux_event_pipe[0], &buf, 1);
3954 while (ret >= 0 || (ret == -1 && errno == EINTR));
3955 }
3956
3957 /* Put something in the pipe, so the event loop wakes up. */
3958 static void
3959 async_file_mark (void)
3960 {
3961 int ret;
3962
3963 async_file_flush ();
3964
3965 do
3966 ret = write (linux_event_pipe[1], "+", 1);
3967 while (ret == 0 || (ret == -1 && errno == EINTR));
3968
3969 /* Ignore EAGAIN. If the pipe is full, the event loop will already
3970 be awakened anyway. */
3971 }
3972
3973 static ptid_t
3974 linux_wait (ptid_t ptid,
3975 struct target_waitstatus *ourstatus, int target_options)
3976 {
3977 ptid_t event_ptid;
3978
3979 /* Flush the async file first. */
3980 if (target_is_async_p ())
3981 async_file_flush ();
3982
3983 do
3984 {
3985 event_ptid = linux_wait_1 (ptid, ourstatus, target_options);
3986 }
3987 while ((target_options & TARGET_WNOHANG) == 0
3988 && ptid_equal (event_ptid, null_ptid)
3989 && ourstatus->kind == TARGET_WAITKIND_IGNORE);
3990
3991 /* If at least one stop was reported, there may be more. A single
3992 SIGCHLD can signal more than one child stop. */
3993 if (target_is_async_p ()
3994 && (target_options & TARGET_WNOHANG) != 0
3995 && !ptid_equal (event_ptid, null_ptid))
3996 async_file_mark ();
3997
3998 return event_ptid;
3999 }
4000
4001 /* Send a signal to an LWP. */
4002
4003 static int
4004 kill_lwp (unsigned long lwpid, int signo)
4005 {
4006 int ret;
4007
4008 errno = 0;
4009 ret = syscall (__NR_tkill, lwpid, signo);
4010 if (errno == ENOSYS)
4011 {
4012 /* If tkill fails, then we are not using nptl threads, a
4013 configuration we no longer support. */
4014 perror_with_name (("tkill"));
4015 }
4016 return ret;
4017 }
4018
4019 void
4020 linux_stop_lwp (struct lwp_info *lwp)
4021 {
4022 send_sigstop (lwp);
4023 }
4024
4025 static void
4026 send_sigstop (struct lwp_info *lwp)
4027 {
4028 int pid;
4029
4030 pid = lwpid_of (get_lwp_thread (lwp));
4031
4032 /* If we already have a pending stop signal for this process, don't
4033 send another. */
4034 if (lwp->stop_expected)
4035 {
4036 if (debug_threads)
4037 debug_printf ("Have pending sigstop for lwp %d\n", pid);
4038
4039 return;
4040 }
4041
4042 if (debug_threads)
4043 debug_printf ("Sending sigstop to lwp %d\n", pid);
4044
4045 lwp->stop_expected = 1;
4046 kill_lwp (pid, SIGSTOP);
4047 }
4048
4049 static int
4050 send_sigstop_callback (thread_info *thread, void *except)
4051 {
4052 struct lwp_info *lwp = get_thread_lwp (thread);
4053
4054 /* Ignore EXCEPT. */
4055 if (lwp == except)
4056 return 0;
4057
4058 if (lwp->stopped)
4059 return 0;
4060
4061 send_sigstop (lwp);
4062 return 0;
4063 }
4064
4065 /* Increment the suspend count of an LWP, and stop it, if not stopped
4066 yet. */
4067 static int
4068 suspend_and_send_sigstop_callback (thread_info *thread, void *except)
4069 {
4070 struct lwp_info *lwp = get_thread_lwp (thread);
4071
4072 /* Ignore EXCEPT. */
4073 if (lwp == except)
4074 return 0;
4075
4076 lwp_suspended_inc (lwp);
4077
4078 return send_sigstop_callback (thread, except);
4079 }
4080
4081 static void
4082 mark_lwp_dead (struct lwp_info *lwp, int wstat)
4083 {
4084 /* Store the exit status for later. */
4085 lwp->status_pending_p = 1;
4086 lwp->status_pending = wstat;
4087
4088 /* Store in waitstatus as well, as there's nothing else to process
4089 for this event. */
4090 if (WIFEXITED (wstat))
4091 {
4092 lwp->waitstatus.kind = TARGET_WAITKIND_EXITED;
4093 lwp->waitstatus.value.integer = WEXITSTATUS (wstat);
4094 }
4095 else if (WIFSIGNALED (wstat))
4096 {
4097 lwp->waitstatus.kind = TARGET_WAITKIND_SIGNALLED;
4098 lwp->waitstatus.value.sig = gdb_signal_from_host (WTERMSIG (wstat));
4099 }
4100
4101 /* Prevent trying to stop it. */
4102 lwp->stopped = 1;
4103
4104 /* No further stops are expected from a dead lwp. */
4105 lwp->stop_expected = 0;
4106 }
4107
4108 /* Return true if LWP has exited already, and has a pending exit event
4109 to report to GDB. */
4110
4111 static int
4112 lwp_is_marked_dead (struct lwp_info *lwp)
4113 {
4114 return (lwp->status_pending_p
4115 && (WIFEXITED (lwp->status_pending)
4116 || WIFSIGNALED (lwp->status_pending)));
4117 }
4118
4119 /* Wait for all children to stop for the SIGSTOPs we just queued. */
4120
4121 static void
4122 wait_for_sigstop (void)
4123 {
4124 struct thread_info *saved_thread;
4125 ptid_t saved_tid;
4126 int wstat;
4127 int ret;
4128
4129 saved_thread = current_thread;
4130 if (saved_thread != NULL)
4131 saved_tid = saved_thread->id;
4132 else
4133 saved_tid = null_ptid; /* avoid bogus unused warning */
4134
4135 if (debug_threads)
4136 debug_printf ("wait_for_sigstop: pulling events\n");
4137
4138 /* Passing NULL_PTID as filter indicates we want all events to be
4139 left pending. Eventually this returns when there are no
4140 unwaited-for children left. */
4141 ret = linux_wait_for_event_filtered (minus_one_ptid, null_ptid,
4142 &wstat, __WALL);
4143 gdb_assert (ret == -1);
4144
4145 if (saved_thread == NULL || linux_thread_alive (saved_tid))
4146 current_thread = saved_thread;
4147 else
4148 {
4149 if (debug_threads)
4150 debug_printf ("Previously current thread died.\n");
4151
4152 /* We can't change the current inferior behind GDB's back,
4153 otherwise, a subsequent command may apply to the wrong
4154 process. */
4155 current_thread = NULL;
4156 }
4157 }
4158
4159 /* Returns true if LWP ENTRY is stopped in a jump pad, and we can't
4160 move it out, because we need to report the stop event to GDB. For
4161 example, if the user puts a breakpoint in the jump pad, it's
4162 because she wants to debug it. */
4163
4164 static int
4165 stuck_in_jump_pad_callback (thread_info *thread, void *data)
4166 {
4167 struct lwp_info *lwp = get_thread_lwp (thread);
4168
4169 if (lwp->suspended != 0)
4170 {
4171 internal_error (__FILE__, __LINE__,
4172 "LWP %ld is suspended, suspended=%d\n",
4173 lwpid_of (thread), lwp->suspended);
4174 }
4175 gdb_assert (lwp->stopped);
4176
4177 /* Allow debugging the jump pad, gdb_collect, etc.. */
4178 return (supports_fast_tracepoints ()
4179 && agent_loaded_p ()
4180 && (gdb_breakpoint_here (lwp->stop_pc)
4181 || lwp->stop_reason == TARGET_STOPPED_BY_WATCHPOINT
4182 || thread->last_resume_kind == resume_step)
4183 && (linux_fast_tracepoint_collecting (lwp, NULL)
4184 != fast_tpoint_collect_result::not_collecting));
4185 }
4186
4187 static void
4188 move_out_of_jump_pad_callback (thread_info *thread)
4189 {
4190 struct thread_info *saved_thread;
4191 struct lwp_info *lwp = get_thread_lwp (thread);
4192 int *wstat;
4193
4194 if (lwp->suspended != 0)
4195 {
4196 internal_error (__FILE__, __LINE__,
4197 "LWP %ld is suspended, suspended=%d\n",
4198 lwpid_of (thread), lwp->suspended);
4199 }
4200 gdb_assert (lwp->stopped);
4201
4202 /* For gdb_breakpoint_here. */
4203 saved_thread = current_thread;
4204 current_thread = thread;
4205
4206 wstat = lwp->status_pending_p ? &lwp->status_pending : NULL;
4207
4208 /* Allow debugging the jump pad, gdb_collect, etc. */
4209 if (!gdb_breakpoint_here (lwp->stop_pc)
4210 && lwp->stop_reason != TARGET_STOPPED_BY_WATCHPOINT
4211 && thread->last_resume_kind != resume_step
4212 && maybe_move_out_of_jump_pad (lwp, wstat))
4213 {
4214 if (debug_threads)
4215 debug_printf ("LWP %ld needs stabilizing (in jump pad)\n",
4216 lwpid_of (thread));
4217
4218 if (wstat)
4219 {
4220 lwp->status_pending_p = 0;
4221 enqueue_one_deferred_signal (lwp, wstat);
4222
4223 if (debug_threads)
4224 debug_printf ("Signal %d for LWP %ld deferred "
4225 "(in jump pad)\n",
4226 WSTOPSIG (*wstat), lwpid_of (thread));
4227 }
4228
4229 linux_resume_one_lwp (lwp, 0, 0, NULL);
4230 }
4231 else
4232 lwp_suspended_inc (lwp);
4233
4234 current_thread = saved_thread;
4235 }
4236
4237 static int
4238 lwp_running (thread_info *thread, void *data)
4239 {
4240 struct lwp_info *lwp = get_thread_lwp (thread);
4241
4242 if (lwp_is_marked_dead (lwp))
4243 return 0;
4244 if (lwp->stopped)
4245 return 0;
4246 return 1;
4247 }
4248
4249 /* Stop all lwps that aren't stopped yet, except EXCEPT, if not NULL.
4250 If SUSPEND, then also increase the suspend count of every LWP,
4251 except EXCEPT. */
4252
4253 static void
4254 stop_all_lwps (int suspend, struct lwp_info *except)
4255 {
4256 /* Should not be called recursively. */
4257 gdb_assert (stopping_threads == NOT_STOPPING_THREADS);
4258
4259 if (debug_threads)
4260 {
4261 debug_enter ();
4262 debug_printf ("stop_all_lwps (%s, except=%s)\n",
4263 suspend ? "stop-and-suspend" : "stop",
4264 except != NULL
4265 ? target_pid_to_str (ptid_of (get_lwp_thread (except)))
4266 : "none");
4267 }
4268
4269 stopping_threads = (suspend
4270 ? STOPPING_AND_SUSPENDING_THREADS
4271 : STOPPING_THREADS);
4272
4273 if (suspend)
4274 find_inferior (&all_threads, suspend_and_send_sigstop_callback, except);
4275 else
4276 find_inferior (&all_threads, send_sigstop_callback, except);
4277 wait_for_sigstop ();
4278 stopping_threads = NOT_STOPPING_THREADS;
4279
4280 if (debug_threads)
4281 {
4282 debug_printf ("stop_all_lwps done, setting stopping_threads "
4283 "back to !stopping\n");
4284 debug_exit ();
4285 }
4286 }
4287
4288 /* Enqueue one signal in the chain of signals which need to be
4289 delivered to this process on next resume. */
4290
4291 static void
4292 enqueue_pending_signal (struct lwp_info *lwp, int signal, siginfo_t *info)
4293 {
4294 struct pending_signals *p_sig = XNEW (struct pending_signals);
4295
4296 p_sig->prev = lwp->pending_signals;
4297 p_sig->signal = signal;
4298 if (info == NULL)
4299 memset (&p_sig->info, 0, sizeof (siginfo_t));
4300 else
4301 memcpy (&p_sig->info, info, sizeof (siginfo_t));
4302 lwp->pending_signals = p_sig;
4303 }
4304
4305 /* Install breakpoints for software single stepping. */
4306
4307 static void
4308 install_software_single_step_breakpoints (struct lwp_info *lwp)
4309 {
4310 struct thread_info *thread = get_lwp_thread (lwp);
4311 struct regcache *regcache = get_thread_regcache (thread, 1);
4312 struct cleanup *old_chain = make_cleanup_restore_current_thread ();
4313
4314 current_thread = thread;
4315 std::vector<CORE_ADDR> next_pcs = the_low_target.get_next_pcs (regcache);
4316
4317 for (CORE_ADDR pc : next_pcs)
4318 set_single_step_breakpoint (pc, current_ptid);
4319
4320 do_cleanups (old_chain);
4321 }
4322
4323 /* Single step via hardware or software single step.
4324 Return 1 if hardware single stepping, 0 if software single stepping
4325 or can't single step. */
4326
4327 static int
4328 single_step (struct lwp_info* lwp)
4329 {
4330 int step = 0;
4331
4332 if (can_hardware_single_step ())
4333 {
4334 step = 1;
4335 }
4336 else if (can_software_single_step ())
4337 {
4338 install_software_single_step_breakpoints (lwp);
4339 step = 0;
4340 }
4341 else
4342 {
4343 if (debug_threads)
4344 debug_printf ("stepping is not implemented on this target");
4345 }
4346
4347 return step;
4348 }
4349
4350 /* The signal can be delivered to the inferior if we are not trying to
4351 finish a fast tracepoint collect. Since signal can be delivered in
4352 the step-over, the program may go to signal handler and trap again
4353 after return from the signal handler. We can live with the spurious
4354 double traps. */
4355
4356 static int
4357 lwp_signal_can_be_delivered (struct lwp_info *lwp)
4358 {
4359 return (lwp->collecting_fast_tracepoint
4360 == fast_tpoint_collect_result::not_collecting);
4361 }
4362
4363 /* Resume execution of LWP. If STEP is nonzero, single-step it. If
4364 SIGNAL is nonzero, give it that signal. */
4365
4366 static void
4367 linux_resume_one_lwp_throw (struct lwp_info *lwp,
4368 int step, int signal, siginfo_t *info)
4369 {
4370 struct thread_info *thread = get_lwp_thread (lwp);
4371 struct thread_info *saved_thread;
4372 int ptrace_request;
4373 struct process_info *proc = get_thread_process (thread);
4374
4375 /* Note that target description may not be initialised
4376 (proc->tdesc == NULL) at this point because the program hasn't
4377 stopped at the first instruction yet. It means GDBserver skips
4378 the extra traps from the wrapper program (see option --wrapper).
4379 Code in this function that requires register access should be
4380 guarded by proc->tdesc == NULL or something else. */
4381
4382 if (lwp->stopped == 0)
4383 return;
4384
4385 gdb_assert (lwp->waitstatus.kind == TARGET_WAITKIND_IGNORE);
4386
4387 fast_tpoint_collect_result fast_tp_collecting
4388 = lwp->collecting_fast_tracepoint;
4389
4390 gdb_assert (!stabilizing_threads
4391 || (fast_tp_collecting
4392 != fast_tpoint_collect_result::not_collecting));
4393
4394 /* Cancel actions that rely on GDB not changing the PC (e.g., the
4395 user used the "jump" command, or "set $pc = foo"). */
4396 if (thread->while_stepping != NULL && lwp->stop_pc != get_pc (lwp))
4397 {
4398 /* Collecting 'while-stepping' actions doesn't make sense
4399 anymore. */
4400 release_while_stepping_state_list (thread);
4401 }
4402
4403 /* If we have pending signals or status, and a new signal, enqueue the
4404 signal. Also enqueue the signal if it can't be delivered to the
4405 inferior right now. */
4406 if (signal != 0
4407 && (lwp->status_pending_p
4408 || lwp->pending_signals != NULL
4409 || !lwp_signal_can_be_delivered (lwp)))
4410 {
4411 enqueue_pending_signal (lwp, signal, info);
4412
4413 /* Postpone any pending signal. It was enqueued above. */
4414 signal = 0;
4415 }
4416
4417 if (lwp->status_pending_p)
4418 {
4419 if (debug_threads)
4420 debug_printf ("Not resuming lwp %ld (%s, stop %s);"
4421 " has pending status\n",
4422 lwpid_of (thread), step ? "step" : "continue",
4423 lwp->stop_expected ? "expected" : "not expected");
4424 return;
4425 }
4426
4427 saved_thread = current_thread;
4428 current_thread = thread;
4429
4430 /* This bit needs some thinking about. If we get a signal that
4431 we must report while a single-step reinsert is still pending,
4432 we often end up resuming the thread. It might be better to
4433 (ew) allow a stack of pending events; then we could be sure that
4434 the reinsert happened right away and not lose any signals.
4435
4436 Making this stack would also shrink the window in which breakpoints are
4437 uninserted (see comment in linux_wait_for_lwp) but not enough for
4438 complete correctness, so it won't solve that problem. It may be
4439 worthwhile just to solve this one, however. */
4440 if (lwp->bp_reinsert != 0)
4441 {
4442 if (debug_threads)
4443 debug_printf (" pending reinsert at 0x%s\n",
4444 paddress (lwp->bp_reinsert));
4445
4446 if (can_hardware_single_step ())
4447 {
4448 if (fast_tp_collecting == fast_tpoint_collect_result::not_collecting)
4449 {
4450 if (step == 0)
4451 warning ("BAD - reinserting but not stepping.");
4452 if (lwp->suspended)
4453 warning ("BAD - reinserting and suspended(%d).",
4454 lwp->suspended);
4455 }
4456 }
4457
4458 step = maybe_hw_step (thread);
4459 }
4460
4461 if (fast_tp_collecting == fast_tpoint_collect_result::before_insn)
4462 {
4463 if (debug_threads)
4464 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
4465 " (exit-jump-pad-bkpt)\n",
4466 lwpid_of (thread));
4467 }
4468 else if (fast_tp_collecting == fast_tpoint_collect_result::at_insn)
4469 {
4470 if (debug_threads)
4471 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
4472 " single-stepping\n",
4473 lwpid_of (thread));
4474
4475 if (can_hardware_single_step ())
4476 step = 1;
4477 else
4478 {
4479 internal_error (__FILE__, __LINE__,
4480 "moving out of jump pad single-stepping"
4481 " not implemented on this target");
4482 }
4483 }
4484
4485 /* If we have while-stepping actions in this thread set it stepping.
4486 If we have a signal to deliver, it may or may not be set to
4487 SIG_IGN, we don't know. Assume so, and allow collecting
4488 while-stepping into a signal handler. A possible smart thing to
4489 do would be to set an internal breakpoint at the signal return
4490 address, continue, and carry on catching this while-stepping
4491 action only when that breakpoint is hit. A future
4492 enhancement. */
4493 if (thread->while_stepping != NULL)
4494 {
4495 if (debug_threads)
4496 debug_printf ("lwp %ld has a while-stepping action -> forcing step.\n",
4497 lwpid_of (thread));
4498
4499 step = single_step (lwp);
4500 }
4501
4502 if (proc->tdesc != NULL && the_low_target.get_pc != NULL)
4503 {
4504 struct regcache *regcache = get_thread_regcache (current_thread, 1);
4505
4506 lwp->stop_pc = (*the_low_target.get_pc) (regcache);
4507
4508 if (debug_threads)
4509 {
4510 debug_printf (" %s from pc 0x%lx\n", step ? "step" : "continue",
4511 (long) lwp->stop_pc);
4512 }
4513 }
4514
4515 /* If we have pending signals, consume one if it can be delivered to
4516 the inferior. */
4517 if (lwp->pending_signals != NULL && lwp_signal_can_be_delivered (lwp))
4518 {
4519 struct pending_signals **p_sig;
4520
4521 p_sig = &lwp->pending_signals;
4522 while ((*p_sig)->prev != NULL)
4523 p_sig = &(*p_sig)->prev;
4524
4525 signal = (*p_sig)->signal;
4526 if ((*p_sig)->info.si_signo != 0)
4527 ptrace (PTRACE_SETSIGINFO, lwpid_of (thread), (PTRACE_TYPE_ARG3) 0,
4528 &(*p_sig)->info);
4529
4530 free (*p_sig);
4531 *p_sig = NULL;
4532 }
4533
4534 if (debug_threads)
4535 debug_printf ("Resuming lwp %ld (%s, signal %d, stop %s)\n",
4536 lwpid_of (thread), step ? "step" : "continue", signal,
4537 lwp->stop_expected ? "expected" : "not expected");
4538
4539 if (the_low_target.prepare_to_resume != NULL)
4540 the_low_target.prepare_to_resume (lwp);
4541
4542 regcache_invalidate_thread (thread);
4543 errno = 0;
4544 lwp->stepping = step;
4545 if (step)
4546 ptrace_request = PTRACE_SINGLESTEP;
4547 else if (gdb_catching_syscalls_p (lwp))
4548 ptrace_request = PTRACE_SYSCALL;
4549 else
4550 ptrace_request = PTRACE_CONT;
4551 ptrace (ptrace_request,
4552 lwpid_of (thread),
4553 (PTRACE_TYPE_ARG3) 0,
4554 /* Coerce to a uintptr_t first to avoid potential gcc warning
4555 of coercing an 8 byte integer to a 4 byte pointer. */
4556 (PTRACE_TYPE_ARG4) (uintptr_t) signal);
4557
4558 current_thread = saved_thread;
4559 if (errno)
4560 perror_with_name ("resuming thread");
4561
4562 /* Successfully resumed. Clear state that no longer makes sense,
4563 and mark the LWP as running. Must not do this before resuming
4564 otherwise if that fails other code will be confused. E.g., we'd
4565 later try to stop the LWP and hang forever waiting for a stop
4566 status. Note that we must not throw after this is cleared,
4567 otherwise handle_zombie_lwp_error would get confused. */
4568 lwp->stopped = 0;
4569 lwp->stop_reason = TARGET_STOPPED_BY_NO_REASON;
4570 }
4571
4572 /* Called when we try to resume a stopped LWP and that errors out. If
4573 the LWP is no longer in ptrace-stopped state (meaning it's zombie,
4574 or about to become), discard the error, clear any pending status
4575 the LWP may have, and return true (we'll collect the exit status
4576 soon enough). Otherwise, return false. */
4577
4578 static int
4579 check_ptrace_stopped_lwp_gone (struct lwp_info *lp)
4580 {
4581 struct thread_info *thread = get_lwp_thread (lp);
4582
4583 /* If we get an error after resuming the LWP successfully, we'd
4584 confuse !T state for the LWP being gone. */
4585 gdb_assert (lp->stopped);
4586
4587 /* We can't just check whether the LWP is in 'Z (Zombie)' state,
4588 because even if ptrace failed with ESRCH, the tracee may be "not
4589 yet fully dead", but already refusing ptrace requests. In that
4590 case the tracee has 'R (Running)' state for a little bit
4591 (observed in Linux 3.18). See also the note on ESRCH in the
4592 ptrace(2) man page. Instead, check whether the LWP has any state
4593 other than ptrace-stopped. */
4594
4595 /* Don't assume anything if /proc/PID/status can't be read. */
4596 if (linux_proc_pid_is_trace_stopped_nowarn (lwpid_of (thread)) == 0)
4597 {
4598 lp->stop_reason = TARGET_STOPPED_BY_NO_REASON;
4599 lp->status_pending_p = 0;
4600 return 1;
4601 }
4602 return 0;
4603 }
4604
4605 /* Like linux_resume_one_lwp_throw, but no error is thrown if the LWP
4606 disappears while we try to resume it. */
4607
4608 static void
4609 linux_resume_one_lwp (struct lwp_info *lwp,
4610 int step, int signal, siginfo_t *info)
4611 {
4612 TRY
4613 {
4614 linux_resume_one_lwp_throw (lwp, step, signal, info);
4615 }
4616 CATCH (ex, RETURN_MASK_ERROR)
4617 {
4618 if (!check_ptrace_stopped_lwp_gone (lwp))
4619 throw_exception (ex);
4620 }
4621 END_CATCH
4622 }
4623
4624 struct thread_resume_array
4625 {
4626 struct thread_resume *resume;
4627 size_t n;
4628 };
4629
4630 /* This function is called once per thread via find_inferior.
4631 ARG is a pointer to a thread_resume_array struct.
4632 We look up the thread specified by ENTRY in ARG, and mark the thread
4633 with a pointer to the appropriate resume request.
4634
4635 This algorithm is O(threads * resume elements), but resume elements
4636 is small (and will remain small at least until GDB supports thread
4637 suspension). */
4638
4639 static int
4640 linux_set_resume_request (thread_info *thread, void *arg)
4641 {
4642 struct lwp_info *lwp = get_thread_lwp (thread);
4643 int ndx;
4644 struct thread_resume_array *r;
4645
4646 r = (struct thread_resume_array *) arg;
4647
4648 for (ndx = 0; ndx < r->n; ndx++)
4649 {
4650 ptid_t ptid = r->resume[ndx].thread;
4651 if (ptid_equal (ptid, minus_one_ptid)
4652 || ptid == thread->id
4653 /* Handle both 'pPID' and 'pPID.-1' as meaning 'all threads
4654 of PID'. */
4655 || (ptid_get_pid (ptid) == pid_of (thread)
4656 && (ptid_is_pid (ptid)
4657 || ptid_get_lwp (ptid) == -1)))
4658 {
4659 if (r->resume[ndx].kind == resume_stop
4660 && thread->last_resume_kind == resume_stop)
4661 {
4662 if (debug_threads)
4663 debug_printf ("already %s LWP %ld at GDB's request\n",
4664 (thread->last_status.kind
4665 == TARGET_WAITKIND_STOPPED)
4666 ? "stopped"
4667 : "stopping",
4668 lwpid_of (thread));
4669
4670 continue;
4671 }
4672
4673 /* Ignore (wildcard) resume requests for already-resumed
4674 threads. */
4675 if (r->resume[ndx].kind != resume_stop
4676 && thread->last_resume_kind != resume_stop)
4677 {
4678 if (debug_threads)
4679 debug_printf ("already %s LWP %ld at GDB's request\n",
4680 (thread->last_resume_kind
4681 == resume_step)
4682 ? "stepping"
4683 : "continuing",
4684 lwpid_of (thread));
4685 continue;
4686 }
4687
4688 /* Don't let wildcard resumes resume fork children that GDB
4689 does not yet know are new fork children. */
4690 if (lwp->fork_relative != NULL)
4691 {
4692 struct lwp_info *rel = lwp->fork_relative;
4693
4694 if (rel->status_pending_p
4695 && (rel->waitstatus.kind == TARGET_WAITKIND_FORKED
4696 || rel->waitstatus.kind == TARGET_WAITKIND_VFORKED))
4697 {
4698 if (debug_threads)
4699 debug_printf ("not resuming LWP %ld: has queued stop reply\n",
4700 lwpid_of (thread));
4701 continue;
4702 }
4703 }
4704
4705 /* If the thread has a pending event that has already been
4706 reported to GDBserver core, but GDB has not pulled the
4707 event out of the vStopped queue yet, likewise, ignore the
4708 (wildcard) resume request. */
4709 if (in_queued_stop_replies (thread->id))
4710 {
4711 if (debug_threads)
4712 debug_printf ("not resuming LWP %ld: has queued stop reply\n",
4713 lwpid_of (thread));
4714 continue;
4715 }
4716
4717 lwp->resume = &r->resume[ndx];
4718 thread->last_resume_kind = lwp->resume->kind;
4719
4720 lwp->step_range_start = lwp->resume->step_range_start;
4721 lwp->step_range_end = lwp->resume->step_range_end;
4722
4723 /* If we had a deferred signal to report, dequeue one now.
4724 This can happen if LWP gets more than one signal while
4725 trying to get out of a jump pad. */
4726 if (lwp->stopped
4727 && !lwp->status_pending_p
4728 && dequeue_one_deferred_signal (lwp, &lwp->status_pending))
4729 {
4730 lwp->status_pending_p = 1;
4731
4732 if (debug_threads)
4733 debug_printf ("Dequeueing deferred signal %d for LWP %ld, "
4734 "leaving status pending.\n",
4735 WSTOPSIG (lwp->status_pending),
4736 lwpid_of (thread));
4737 }
4738
4739 return 0;
4740 }
4741 }
4742
4743 /* No resume action for this thread. */
4744 lwp->resume = NULL;
4745
4746 return 0;
4747 }
4748
4749 /* find_inferior callback for linux_resume.
4750 Set *FLAG_P if this lwp has an interesting status pending. */
4751
4752 static int
4753 resume_status_pending_p (thread_info *thread, void *flag_p)
4754 {
4755 struct lwp_info *lwp = get_thread_lwp (thread);
4756
4757 /* LWPs which will not be resumed are not interesting, because
4758 we might not wait for them next time through linux_wait. */
4759 if (lwp->resume == NULL)
4760 return 0;
4761
4762 if (thread_still_has_status_pending_p (thread))
4763 * (int *) flag_p = 1;
4764
4765 return 0;
4766 }
4767
4768 /* Return 1 if this lwp that GDB wants running is stopped at an
4769 internal breakpoint that we need to step over. It assumes that any
4770 required STOP_PC adjustment has already been propagated to the
4771 inferior's regcache. */
4772
4773 static int
4774 need_step_over_p (thread_info *thread, void *dummy)
4775 {
4776 struct lwp_info *lwp = get_thread_lwp (thread);
4777 struct thread_info *saved_thread;
4778 CORE_ADDR pc;
4779 struct process_info *proc = get_thread_process (thread);
4780
4781 /* GDBserver is skipping the extra traps from the wrapper program,
4782 don't have to do step over. */
4783 if (proc->tdesc == NULL)
4784 return 0;
4785
4786 /* LWPs which will not be resumed are not interesting, because we
4787 might not wait for them next time through linux_wait. */
4788
4789 if (!lwp->stopped)
4790 {
4791 if (debug_threads)
4792 debug_printf ("Need step over [LWP %ld]? Ignoring, not stopped\n",
4793 lwpid_of (thread));
4794 return 0;
4795 }
4796
4797 if (thread->last_resume_kind == resume_stop)
4798 {
4799 if (debug_threads)
4800 debug_printf ("Need step over [LWP %ld]? Ignoring, should remain"
4801 " stopped\n",
4802 lwpid_of (thread));
4803 return 0;
4804 }
4805
4806 gdb_assert (lwp->suspended >= 0);
4807
4808 if (lwp->suspended)
4809 {
4810 if (debug_threads)
4811 debug_printf ("Need step over [LWP %ld]? Ignoring, suspended\n",
4812 lwpid_of (thread));
4813 return 0;
4814 }
4815
4816 if (lwp->status_pending_p)
4817 {
4818 if (debug_threads)
4819 debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
4820 " status.\n",
4821 lwpid_of (thread));
4822 return 0;
4823 }
4824
4825 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
4826 or we have. */
4827 pc = get_pc (lwp);
4828
4829 /* If the PC has changed since we stopped, then don't do anything,
4830 and let the breakpoint/tracepoint be hit. This happens if, for
4831 instance, GDB handled the decr_pc_after_break subtraction itself,
4832 GDB is OOL stepping this thread, or the user has issued a "jump"
4833 command, or poked thread's registers herself. */
4834 if (pc != lwp->stop_pc)
4835 {
4836 if (debug_threads)
4837 debug_printf ("Need step over [LWP %ld]? Cancelling, PC was changed. "
4838 "Old stop_pc was 0x%s, PC is now 0x%s\n",
4839 lwpid_of (thread),
4840 paddress (lwp->stop_pc), paddress (pc));
4841 return 0;
4842 }
4843
4844 /* On software single step target, resume the inferior with signal
4845 rather than stepping over. */
4846 if (can_software_single_step ()
4847 && lwp->pending_signals != NULL
4848 && lwp_signal_can_be_delivered (lwp))
4849 {
4850 if (debug_threads)
4851 debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
4852 " signals.\n",
4853 lwpid_of (thread));
4854
4855 return 0;
4856 }
4857
4858 saved_thread = current_thread;
4859 current_thread = thread;
4860
4861 /* We can only step over breakpoints we know about. */
4862 if (breakpoint_here (pc) || fast_tracepoint_jump_here (pc))
4863 {
4864 /* Don't step over a breakpoint that GDB expects to hit
4865 though. If the condition is being evaluated on the target's side
4866 and it evaluate to false, step over this breakpoint as well. */
4867 if (gdb_breakpoint_here (pc)
4868 && gdb_condition_true_at_breakpoint (pc)
4869 && gdb_no_commands_at_breakpoint (pc))
4870 {
4871 if (debug_threads)
4872 debug_printf ("Need step over [LWP %ld]? yes, but found"
4873 " GDB breakpoint at 0x%s; skipping step over\n",
4874 lwpid_of (thread), paddress (pc));
4875
4876 current_thread = saved_thread;
4877 return 0;
4878 }
4879 else
4880 {
4881 if (debug_threads)
4882 debug_printf ("Need step over [LWP %ld]? yes, "
4883 "found breakpoint at 0x%s\n",
4884 lwpid_of (thread), paddress (pc));
4885
4886 /* We've found an lwp that needs stepping over --- return 1 so
4887 that find_inferior stops looking. */
4888 current_thread = saved_thread;
4889
4890 return 1;
4891 }
4892 }
4893
4894 current_thread = saved_thread;
4895
4896 if (debug_threads)
4897 debug_printf ("Need step over [LWP %ld]? No, no breakpoint found"
4898 " at 0x%s\n",
4899 lwpid_of (thread), paddress (pc));
4900
4901 return 0;
4902 }
4903
4904 /* Start a step-over operation on LWP. When LWP stopped at a
4905 breakpoint, to make progress, we need to remove the breakpoint out
4906 of the way. If we let other threads run while we do that, they may
4907 pass by the breakpoint location and miss hitting it. To avoid
4908 that, a step-over momentarily stops all threads while LWP is
4909 single-stepped by either hardware or software while the breakpoint
4910 is temporarily uninserted from the inferior. When the single-step
4911 finishes, we reinsert the breakpoint, and let all threads that are
4912 supposed to be running, run again. */
4913
4914 static int
4915 start_step_over (struct lwp_info *lwp)
4916 {
4917 struct thread_info *thread = get_lwp_thread (lwp);
4918 struct thread_info *saved_thread;
4919 CORE_ADDR pc;
4920 int step;
4921
4922 if (debug_threads)
4923 debug_printf ("Starting step-over on LWP %ld. Stopping all threads\n",
4924 lwpid_of (thread));
4925
4926 stop_all_lwps (1, lwp);
4927
4928 if (lwp->suspended != 0)
4929 {
4930 internal_error (__FILE__, __LINE__,
4931 "LWP %ld suspended=%d\n", lwpid_of (thread),
4932 lwp->suspended);
4933 }
4934
4935 if (debug_threads)
4936 debug_printf ("Done stopping all threads for step-over.\n");
4937
4938 /* Note, we should always reach here with an already adjusted PC,
4939 either by GDB (if we're resuming due to GDB's request), or by our
4940 caller, if we just finished handling an internal breakpoint GDB
4941 shouldn't care about. */
4942 pc = get_pc (lwp);
4943
4944 saved_thread = current_thread;
4945 current_thread = thread;
4946
4947 lwp->bp_reinsert = pc;
4948 uninsert_breakpoints_at (pc);
4949 uninsert_fast_tracepoint_jumps_at (pc);
4950
4951 step = single_step (lwp);
4952
4953 current_thread = saved_thread;
4954
4955 linux_resume_one_lwp (lwp, step, 0, NULL);
4956
4957 /* Require next event from this LWP. */
4958 step_over_bkpt = thread->id;
4959 return 1;
4960 }
4961
4962 /* Finish a step-over. Reinsert the breakpoint we had uninserted in
4963 start_step_over, if still there, and delete any single-step
4964 breakpoints we've set, on non hardware single-step targets. */
4965
4966 static int
4967 finish_step_over (struct lwp_info *lwp)
4968 {
4969 if (lwp->bp_reinsert != 0)
4970 {
4971 struct thread_info *saved_thread = current_thread;
4972
4973 if (debug_threads)
4974 debug_printf ("Finished step over.\n");
4975
4976 current_thread = get_lwp_thread (lwp);
4977
4978 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
4979 may be no breakpoint to reinsert there by now. */
4980 reinsert_breakpoints_at (lwp->bp_reinsert);
4981 reinsert_fast_tracepoint_jumps_at (lwp->bp_reinsert);
4982
4983 lwp->bp_reinsert = 0;
4984
4985 /* Delete any single-step breakpoints. No longer needed. We
4986 don't have to worry about other threads hitting this trap,
4987 and later not being able to explain it, because we were
4988 stepping over a breakpoint, and we hold all threads but
4989 LWP stopped while doing that. */
4990 if (!can_hardware_single_step ())
4991 {
4992 gdb_assert (has_single_step_breakpoints (current_thread));
4993 delete_single_step_breakpoints (current_thread);
4994 }
4995
4996 step_over_bkpt = null_ptid;
4997 current_thread = saved_thread;
4998 return 1;
4999 }
5000 else
5001 return 0;
5002 }
5003
5004 /* If there's a step over in progress, wait until all threads stop
5005 (that is, until the stepping thread finishes its step), and
5006 unsuspend all lwps. The stepping thread ends with its status
5007 pending, which is processed later when we get back to processing
5008 events. */
5009
5010 static void
5011 complete_ongoing_step_over (void)
5012 {
5013 if (!ptid_equal (step_over_bkpt, null_ptid))
5014 {
5015 struct lwp_info *lwp;
5016 int wstat;
5017 int ret;
5018
5019 if (debug_threads)
5020 debug_printf ("detach: step over in progress, finish it first\n");
5021
5022 /* Passing NULL_PTID as filter indicates we want all events to
5023 be left pending. Eventually this returns when there are no
5024 unwaited-for children left. */
5025 ret = linux_wait_for_event_filtered (minus_one_ptid, null_ptid,
5026 &wstat, __WALL);
5027 gdb_assert (ret == -1);
5028
5029 lwp = find_lwp_pid (step_over_bkpt);
5030 if (lwp != NULL)
5031 finish_step_over (lwp);
5032 step_over_bkpt = null_ptid;
5033 unsuspend_all_lwps (lwp);
5034 }
5035 }
5036
5037 /* This function is called once per thread. We check the thread's resume
5038 request, which will tell us whether to resume, step, or leave the thread
5039 stopped; and what signal, if any, it should be sent.
5040
5041 For threads which we aren't explicitly told otherwise, we preserve
5042 the stepping flag; this is used for stepping over gdbserver-placed
5043 breakpoints.
5044
5045 If pending_flags was set in any thread, we queue any needed
5046 signals, since we won't actually resume. We already have a pending
5047 event to report, so we don't need to preserve any step requests;
5048 they should be re-issued if necessary. */
5049
5050 static int
5051 linux_resume_one_thread (thread_info *thread, void *arg)
5052 {
5053 struct lwp_info *lwp = get_thread_lwp (thread);
5054 int leave_all_stopped = * (int *) arg;
5055 int leave_pending;
5056
5057 if (lwp->resume == NULL)
5058 return 0;
5059
5060 if (lwp->resume->kind == resume_stop)
5061 {
5062 if (debug_threads)
5063 debug_printf ("resume_stop request for LWP %ld\n", lwpid_of (thread));
5064
5065 if (!lwp->stopped)
5066 {
5067 if (debug_threads)
5068 debug_printf ("stopping LWP %ld\n", lwpid_of (thread));
5069
5070 /* Stop the thread, and wait for the event asynchronously,
5071 through the event loop. */
5072 send_sigstop (lwp);
5073 }
5074 else
5075 {
5076 if (debug_threads)
5077 debug_printf ("already stopped LWP %ld\n",
5078 lwpid_of (thread));
5079
5080 /* The LWP may have been stopped in an internal event that
5081 was not meant to be notified back to GDB (e.g., gdbserver
5082 breakpoint), so we should be reporting a stop event in
5083 this case too. */
5084
5085 /* If the thread already has a pending SIGSTOP, this is a
5086 no-op. Otherwise, something later will presumably resume
5087 the thread and this will cause it to cancel any pending
5088 operation, due to last_resume_kind == resume_stop. If
5089 the thread already has a pending status to report, we
5090 will still report it the next time we wait - see
5091 status_pending_p_callback. */
5092
5093 /* If we already have a pending signal to report, then
5094 there's no need to queue a SIGSTOP, as this means we're
5095 midway through moving the LWP out of the jumppad, and we
5096 will report the pending signal as soon as that is
5097 finished. */
5098 if (lwp->pending_signals_to_report == NULL)
5099 send_sigstop (lwp);
5100 }
5101
5102 /* For stop requests, we're done. */
5103 lwp->resume = NULL;
5104 thread->last_status.kind = TARGET_WAITKIND_IGNORE;
5105 return 0;
5106 }
5107
5108 /* If this thread which is about to be resumed has a pending status,
5109 then don't resume it - we can just report the pending status.
5110 Likewise if it is suspended, because e.g., another thread is
5111 stepping past a breakpoint. Make sure to queue any signals that
5112 would otherwise be sent. In all-stop mode, we do this decision
5113 based on if *any* thread has a pending status. If there's a
5114 thread that needs the step-over-breakpoint dance, then don't
5115 resume any other thread but that particular one. */
5116 leave_pending = (lwp->suspended
5117 || lwp->status_pending_p
5118 || leave_all_stopped);
5119
5120 /* If we have a new signal, enqueue the signal. */
5121 if (lwp->resume->sig != 0)
5122 {
5123 siginfo_t info, *info_p;
5124
5125 /* If this is the same signal we were previously stopped by,
5126 make sure to queue its siginfo. */
5127 if (WIFSTOPPED (lwp->last_status)
5128 && WSTOPSIG (lwp->last_status) == lwp->resume->sig
5129 && ptrace (PTRACE_GETSIGINFO, lwpid_of (thread),
5130 (PTRACE_TYPE_ARG3) 0, &info) == 0)
5131 info_p = &info;
5132 else
5133 info_p = NULL;
5134
5135 enqueue_pending_signal (lwp, lwp->resume->sig, info_p);
5136 }
5137
5138 if (!leave_pending)
5139 {
5140 if (debug_threads)
5141 debug_printf ("resuming LWP %ld\n", lwpid_of (thread));
5142
5143 proceed_one_lwp (thread, NULL);
5144 }
5145 else
5146 {
5147 if (debug_threads)
5148 debug_printf ("leaving LWP %ld stopped\n", lwpid_of (thread));
5149 }
5150
5151 thread->last_status.kind = TARGET_WAITKIND_IGNORE;
5152 lwp->resume = NULL;
5153 return 0;
5154 }
5155
5156 static void
5157 linux_resume (struct thread_resume *resume_info, size_t n)
5158 {
5159 struct thread_resume_array array = { resume_info, n };
5160 struct thread_info *need_step_over = NULL;
5161 int any_pending;
5162 int leave_all_stopped;
5163
5164 if (debug_threads)
5165 {
5166 debug_enter ();
5167 debug_printf ("linux_resume:\n");
5168 }
5169
5170 find_inferior (&all_threads, linux_set_resume_request, &array);
5171
5172 /* If there is a thread which would otherwise be resumed, which has
5173 a pending status, then don't resume any threads - we can just
5174 report the pending status. Make sure to queue any signals that
5175 would otherwise be sent. In non-stop mode, we'll apply this
5176 logic to each thread individually. We consume all pending events
5177 before considering to start a step-over (in all-stop). */
5178 any_pending = 0;
5179 if (!non_stop)
5180 find_inferior (&all_threads, resume_status_pending_p, &any_pending);
5181
5182 /* If there is a thread which would otherwise be resumed, which is
5183 stopped at a breakpoint that needs stepping over, then don't
5184 resume any threads - have it step over the breakpoint with all
5185 other threads stopped, then resume all threads again. Make sure
5186 to queue any signals that would otherwise be delivered or
5187 queued. */
5188 if (!any_pending && supports_breakpoints ())
5189 need_step_over
5190 = (struct thread_info *) find_inferior (&all_threads,
5191 need_step_over_p, NULL);
5192
5193 leave_all_stopped = (need_step_over != NULL || any_pending);
5194
5195 if (debug_threads)
5196 {
5197 if (need_step_over != NULL)
5198 debug_printf ("Not resuming all, need step over\n");
5199 else if (any_pending)
5200 debug_printf ("Not resuming, all-stop and found "
5201 "an LWP with pending status\n");
5202 else
5203 debug_printf ("Resuming, no pending status or step over needed\n");
5204 }
5205
5206 /* Even if we're leaving threads stopped, queue all signals we'd
5207 otherwise deliver. */
5208 find_inferior (&all_threads, linux_resume_one_thread, &leave_all_stopped);
5209
5210 if (need_step_over)
5211 start_step_over (get_thread_lwp (need_step_over));
5212
5213 if (debug_threads)
5214 {
5215 debug_printf ("linux_resume done\n");
5216 debug_exit ();
5217 }
5218
5219 /* We may have events that were pending that can/should be sent to
5220 the client now. Trigger a linux_wait call. */
5221 if (target_is_async_p ())
5222 async_file_mark ();
5223 }
5224
5225 /* This function is called once per thread. We check the thread's
5226 last resume request, which will tell us whether to resume, step, or
5227 leave the thread stopped. Any signal the client requested to be
5228 delivered has already been enqueued at this point.
5229
5230 If any thread that GDB wants running is stopped at an internal
5231 breakpoint that needs stepping over, we start a step-over operation
5232 on that particular thread, and leave all others stopped. */
5233
5234 static int
5235 proceed_one_lwp (thread_info *thread, void *except)
5236 {
5237 struct lwp_info *lwp = get_thread_lwp (thread);
5238 int step;
5239
5240 if (lwp == except)
5241 return 0;
5242
5243 if (debug_threads)
5244 debug_printf ("proceed_one_lwp: lwp %ld\n", lwpid_of (thread));
5245
5246 if (!lwp->stopped)
5247 {
5248 if (debug_threads)
5249 debug_printf (" LWP %ld already running\n", lwpid_of (thread));
5250 return 0;
5251 }
5252
5253 if (thread->last_resume_kind == resume_stop
5254 && thread->last_status.kind != TARGET_WAITKIND_IGNORE)
5255 {
5256 if (debug_threads)
5257 debug_printf (" client wants LWP to remain %ld stopped\n",
5258 lwpid_of (thread));
5259 return 0;
5260 }
5261
5262 if (lwp->status_pending_p)
5263 {
5264 if (debug_threads)
5265 debug_printf (" LWP %ld has pending status, leaving stopped\n",
5266 lwpid_of (thread));
5267 return 0;
5268 }
5269
5270 gdb_assert (lwp->suspended >= 0);
5271
5272 if (lwp->suspended)
5273 {
5274 if (debug_threads)
5275 debug_printf (" LWP %ld is suspended\n", lwpid_of (thread));
5276 return 0;
5277 }
5278
5279 if (thread->last_resume_kind == resume_stop
5280 && lwp->pending_signals_to_report == NULL
5281 && (lwp->collecting_fast_tracepoint
5282 == fast_tpoint_collect_result::not_collecting))
5283 {
5284 /* We haven't reported this LWP as stopped yet (otherwise, the
5285 last_status.kind check above would catch it, and we wouldn't
5286 reach here. This LWP may have been momentarily paused by a
5287 stop_all_lwps call while handling for example, another LWP's
5288 step-over. In that case, the pending expected SIGSTOP signal
5289 that was queued at vCont;t handling time will have already
5290 been consumed by wait_for_sigstop, and so we need to requeue
5291 another one here. Note that if the LWP already has a SIGSTOP
5292 pending, this is a no-op. */
5293
5294 if (debug_threads)
5295 debug_printf ("Client wants LWP %ld to stop. "
5296 "Making sure it has a SIGSTOP pending\n",
5297 lwpid_of (thread));
5298
5299 send_sigstop (lwp);
5300 }
5301
5302 if (thread->last_resume_kind == resume_step)
5303 {
5304 if (debug_threads)
5305 debug_printf (" stepping LWP %ld, client wants it stepping\n",
5306 lwpid_of (thread));
5307
5308 /* If resume_step is requested by GDB, install single-step
5309 breakpoints when the thread is about to be actually resumed if
5310 the single-step breakpoints weren't removed. */
5311 if (can_software_single_step ()
5312 && !has_single_step_breakpoints (thread))
5313 install_software_single_step_breakpoints (lwp);
5314
5315 step = maybe_hw_step (thread);
5316 }
5317 else if (lwp->bp_reinsert != 0)
5318 {
5319 if (debug_threads)
5320 debug_printf (" stepping LWP %ld, reinsert set\n",
5321 lwpid_of (thread));
5322
5323 step = maybe_hw_step (thread);
5324 }
5325 else
5326 step = 0;
5327
5328 linux_resume_one_lwp (lwp, step, 0, NULL);
5329 return 0;
5330 }
5331
5332 static int
5333 unsuspend_and_proceed_one_lwp (thread_info *thread, void *except)
5334 {
5335 struct lwp_info *lwp = get_thread_lwp (thread);
5336
5337 if (lwp == except)
5338 return 0;
5339
5340 lwp_suspended_decr (lwp);
5341
5342 return proceed_one_lwp (thread, except);
5343 }
5344
5345 /* When we finish a step-over, set threads running again. If there's
5346 another thread that may need a step-over, now's the time to start
5347 it. Eventually, we'll move all threads past their breakpoints. */
5348
5349 static void
5350 proceed_all_lwps (void)
5351 {
5352 struct thread_info *need_step_over;
5353
5354 /* If there is a thread which would otherwise be resumed, which is
5355 stopped at a breakpoint that needs stepping over, then don't
5356 resume any threads - have it step over the breakpoint with all
5357 other threads stopped, then resume all threads again. */
5358
5359 if (supports_breakpoints ())
5360 {
5361 need_step_over
5362 = (struct thread_info *) find_inferior (&all_threads,
5363 need_step_over_p, NULL);
5364
5365 if (need_step_over != NULL)
5366 {
5367 if (debug_threads)
5368 debug_printf ("proceed_all_lwps: found "
5369 "thread %ld needing a step-over\n",
5370 lwpid_of (need_step_over));
5371
5372 start_step_over (get_thread_lwp (need_step_over));
5373 return;
5374 }
5375 }
5376
5377 if (debug_threads)
5378 debug_printf ("Proceeding, no step-over needed\n");
5379
5380 find_inferior (&all_threads, proceed_one_lwp, NULL);
5381 }
5382
5383 /* Stopped LWPs that the client wanted to be running, that don't have
5384 pending statuses, are set to run again, except for EXCEPT, if not
5385 NULL. This undoes a stop_all_lwps call. */
5386
5387 static void
5388 unstop_all_lwps (int unsuspend, struct lwp_info *except)
5389 {
5390 if (debug_threads)
5391 {
5392 debug_enter ();
5393 if (except)
5394 debug_printf ("unstopping all lwps, except=(LWP %ld)\n",
5395 lwpid_of (get_lwp_thread (except)));
5396 else
5397 debug_printf ("unstopping all lwps\n");
5398 }
5399
5400 if (unsuspend)
5401 find_inferior (&all_threads, unsuspend_and_proceed_one_lwp, except);
5402 else
5403 find_inferior (&all_threads, proceed_one_lwp, except);
5404
5405 if (debug_threads)
5406 {
5407 debug_printf ("unstop_all_lwps done\n");
5408 debug_exit ();
5409 }
5410 }
5411
5412
5413 #ifdef HAVE_LINUX_REGSETS
5414
5415 #define use_linux_regsets 1
5416
5417 /* Returns true if REGSET has been disabled. */
5418
5419 static int
5420 regset_disabled (struct regsets_info *info, struct regset_info *regset)
5421 {
5422 return (info->disabled_regsets != NULL
5423 && info->disabled_regsets[regset - info->regsets]);
5424 }
5425
5426 /* Disable REGSET. */
5427
5428 static void
5429 disable_regset (struct regsets_info *info, struct regset_info *regset)
5430 {
5431 int dr_offset;
5432
5433 dr_offset = regset - info->regsets;
5434 if (info->disabled_regsets == NULL)
5435 info->disabled_regsets = (char *) xcalloc (1, info->num_regsets);
5436 info->disabled_regsets[dr_offset] = 1;
5437 }
5438
5439 static int
5440 regsets_fetch_inferior_registers (struct regsets_info *regsets_info,
5441 struct regcache *regcache)
5442 {
5443 struct regset_info *regset;
5444 int saw_general_regs = 0;
5445 int pid;
5446 struct iovec iov;
5447
5448 pid = lwpid_of (current_thread);
5449 for (regset = regsets_info->regsets; regset->size >= 0; regset++)
5450 {
5451 void *buf, *data;
5452 int nt_type, res;
5453
5454 if (regset->size == 0 || regset_disabled (regsets_info, regset))
5455 continue;
5456
5457 buf = xmalloc (regset->size);
5458
5459 nt_type = regset->nt_type;
5460 if (nt_type)
5461 {
5462 iov.iov_base = buf;
5463 iov.iov_len = regset->size;
5464 data = (void *) &iov;
5465 }
5466 else
5467 data = buf;
5468
5469 #ifndef __sparc__
5470 res = ptrace (regset->get_request, pid,
5471 (PTRACE_TYPE_ARG3) (long) nt_type, data);
5472 #else
5473 res = ptrace (regset->get_request, pid, data, nt_type);
5474 #endif
5475 if (res < 0)
5476 {
5477 if (errno == EIO)
5478 {
5479 /* If we get EIO on a regset, do not try it again for
5480 this process mode. */
5481 disable_regset (regsets_info, regset);
5482 }
5483 else if (errno == ENODATA)
5484 {
5485 /* ENODATA may be returned if the regset is currently
5486 not "active". This can happen in normal operation,
5487 so suppress the warning in this case. */
5488 }
5489 else if (errno == ESRCH)
5490 {
5491 /* At this point, ESRCH should mean the process is
5492 already gone, in which case we simply ignore attempts
5493 to read its registers. */
5494 }
5495 else
5496 {
5497 char s[256];
5498 sprintf (s, "ptrace(regsets_fetch_inferior_registers) PID=%d",
5499 pid);
5500 perror (s);
5501 }
5502 }
5503 else
5504 {
5505 if (regset->type == GENERAL_REGS)
5506 saw_general_regs = 1;
5507 regset->store_function (regcache, buf);
5508 }
5509 free (buf);
5510 }
5511 if (saw_general_regs)
5512 return 0;
5513 else
5514 return 1;
5515 }
5516
5517 static int
5518 regsets_store_inferior_registers (struct regsets_info *regsets_info,
5519 struct regcache *regcache)
5520 {
5521 struct regset_info *regset;
5522 int saw_general_regs = 0;
5523 int pid;
5524 struct iovec iov;
5525
5526 pid = lwpid_of (current_thread);
5527 for (regset = regsets_info->regsets; regset->size >= 0; regset++)
5528 {
5529 void *buf, *data;
5530 int nt_type, res;
5531
5532 if (regset->size == 0 || regset_disabled (regsets_info, regset)
5533 || regset->fill_function == NULL)
5534 continue;
5535
5536 buf = xmalloc (regset->size);
5537
5538 /* First fill the buffer with the current register set contents,
5539 in case there are any items in the kernel's regset that are
5540 not in gdbserver's regcache. */
5541
5542 nt_type = regset->nt_type;
5543 if (nt_type)
5544 {
5545 iov.iov_base = buf;
5546 iov.iov_len = regset->size;
5547 data = (void *) &iov;
5548 }
5549 else
5550 data = buf;
5551
5552 #ifndef __sparc__
5553 res = ptrace (regset->get_request, pid,
5554 (PTRACE_TYPE_ARG3) (long) nt_type, data);
5555 #else
5556 res = ptrace (regset->get_request, pid, data, nt_type);
5557 #endif
5558
5559 if (res == 0)
5560 {
5561 /* Then overlay our cached registers on that. */
5562 regset->fill_function (regcache, buf);
5563
5564 /* Only now do we write the register set. */
5565 #ifndef __sparc__
5566 res = ptrace (regset->set_request, pid,
5567 (PTRACE_TYPE_ARG3) (long) nt_type, data);
5568 #else
5569 res = ptrace (regset->set_request, pid, data, nt_type);
5570 #endif
5571 }
5572
5573 if (res < 0)
5574 {
5575 if (errno == EIO)
5576 {
5577 /* If we get EIO on a regset, do not try it again for
5578 this process mode. */
5579 disable_regset (regsets_info, regset);
5580 }
5581 else if (errno == ESRCH)
5582 {
5583 /* At this point, ESRCH should mean the process is
5584 already gone, in which case we simply ignore attempts
5585 to change its registers. See also the related
5586 comment in linux_resume_one_lwp. */
5587 free (buf);
5588 return 0;
5589 }
5590 else
5591 {
5592 perror ("Warning: ptrace(regsets_store_inferior_registers)");
5593 }
5594 }
5595 else if (regset->type == GENERAL_REGS)
5596 saw_general_regs = 1;
5597 free (buf);
5598 }
5599 if (saw_general_regs)
5600 return 0;
5601 else
5602 return 1;
5603 }
5604
5605 #else /* !HAVE_LINUX_REGSETS */
5606
5607 #define use_linux_regsets 0
5608 #define regsets_fetch_inferior_registers(regsets_info, regcache) 1
5609 #define regsets_store_inferior_registers(regsets_info, regcache) 1
5610
5611 #endif
5612
5613 /* Return 1 if register REGNO is supported by one of the regset ptrace
5614 calls or 0 if it has to be transferred individually. */
5615
5616 static int
5617 linux_register_in_regsets (const struct regs_info *regs_info, int regno)
5618 {
5619 unsigned char mask = 1 << (regno % 8);
5620 size_t index = regno / 8;
5621
5622 return (use_linux_regsets
5623 && (regs_info->regset_bitmap == NULL
5624 || (regs_info->regset_bitmap[index] & mask) != 0));
5625 }
5626
5627 #ifdef HAVE_LINUX_USRREGS
5628
5629 static int
5630 register_addr (const struct usrregs_info *usrregs, int regnum)
5631 {
5632 int addr;
5633
5634 if (regnum < 0 || regnum >= usrregs->num_regs)
5635 error ("Invalid register number %d.", regnum);
5636
5637 addr = usrregs->regmap[regnum];
5638
5639 return addr;
5640 }
5641
5642 /* Fetch one register. */
5643 static void
5644 fetch_register (const struct usrregs_info *usrregs,
5645 struct regcache *regcache, int regno)
5646 {
5647 CORE_ADDR regaddr;
5648 int i, size;
5649 char *buf;
5650 int pid;
5651
5652 if (regno >= usrregs->num_regs)
5653 return;
5654 if ((*the_low_target.cannot_fetch_register) (regno))
5655 return;
5656
5657 regaddr = register_addr (usrregs, regno);
5658 if (regaddr == -1)
5659 return;
5660
5661 size = ((register_size (regcache->tdesc, regno)
5662 + sizeof (PTRACE_XFER_TYPE) - 1)
5663 & -sizeof (PTRACE_XFER_TYPE));
5664 buf = (char *) alloca (size);
5665
5666 pid = lwpid_of (current_thread);
5667 for (i = 0; i < size; i += sizeof (PTRACE_XFER_TYPE))
5668 {
5669 errno = 0;
5670 *(PTRACE_XFER_TYPE *) (buf + i) =
5671 ptrace (PTRACE_PEEKUSER, pid,
5672 /* Coerce to a uintptr_t first to avoid potential gcc warning
5673 of coercing an 8 byte integer to a 4 byte pointer. */
5674 (PTRACE_TYPE_ARG3) (uintptr_t) regaddr, (PTRACE_TYPE_ARG4) 0);
5675 regaddr += sizeof (PTRACE_XFER_TYPE);
5676 if (errno != 0)
5677 error ("reading register %d: %s", regno, strerror (errno));
5678 }
5679
5680 if (the_low_target.supply_ptrace_register)
5681 the_low_target.supply_ptrace_register (regcache, regno, buf);
5682 else
5683 supply_register (regcache, regno, buf);
5684 }
5685
5686 /* Store one register. */
5687 static void
5688 store_register (const struct usrregs_info *usrregs,
5689 struct regcache *regcache, int regno)
5690 {
5691 CORE_ADDR regaddr;
5692 int i, size;
5693 char *buf;
5694 int pid;
5695
5696 if (regno >= usrregs->num_regs)
5697 return;
5698 if ((*the_low_target.cannot_store_register) (regno))
5699 return;
5700
5701 regaddr = register_addr (usrregs, regno);
5702 if (regaddr == -1)
5703 return;
5704
5705 size = ((register_size (regcache->tdesc, regno)
5706 + sizeof (PTRACE_XFER_TYPE) - 1)
5707 & -sizeof (PTRACE_XFER_TYPE));
5708 buf = (char *) alloca (size);
5709 memset (buf, 0, size);
5710
5711 if (the_low_target.collect_ptrace_register)
5712 the_low_target.collect_ptrace_register (regcache, regno, buf);
5713 else
5714 collect_register (regcache, regno, buf);
5715
5716 pid = lwpid_of (current_thread);
5717 for (i = 0; i < size; i += sizeof (PTRACE_XFER_TYPE))
5718 {
5719 errno = 0;
5720 ptrace (PTRACE_POKEUSER, pid,
5721 /* Coerce to a uintptr_t first to avoid potential gcc warning
5722 about coercing an 8 byte integer to a 4 byte pointer. */
5723 (PTRACE_TYPE_ARG3) (uintptr_t) regaddr,
5724 (PTRACE_TYPE_ARG4) *(PTRACE_XFER_TYPE *) (buf + i));
5725 if (errno != 0)
5726 {
5727 /* At this point, ESRCH should mean the process is
5728 already gone, in which case we simply ignore attempts
5729 to change its registers. See also the related
5730 comment in linux_resume_one_lwp. */
5731 if (errno == ESRCH)
5732 return;
5733
5734 if ((*the_low_target.cannot_store_register) (regno) == 0)
5735 error ("writing register %d: %s", regno, strerror (errno));
5736 }
5737 regaddr += sizeof (PTRACE_XFER_TYPE);
5738 }
5739 }
5740
5741 /* Fetch all registers, or just one, from the child process.
5742 If REGNO is -1, do this for all registers, skipping any that are
5743 assumed to have been retrieved by regsets_fetch_inferior_registers,
5744 unless ALL is non-zero.
5745 Otherwise, REGNO specifies which register (so we can save time). */
5746 static void
5747 usr_fetch_inferior_registers (const struct regs_info *regs_info,
5748 struct regcache *regcache, int regno, int all)
5749 {
5750 struct usrregs_info *usr = regs_info->usrregs;
5751
5752 if (regno == -1)
5753 {
5754 for (regno = 0; regno < usr->num_regs; regno++)
5755 if (all || !linux_register_in_regsets (regs_info, regno))
5756 fetch_register (usr, regcache, regno);
5757 }
5758 else
5759 fetch_register (usr, regcache, regno);
5760 }
5761
5762 /* Store our register values back into the inferior.
5763 If REGNO is -1, do this for all registers, skipping any that are
5764 assumed to have been saved by regsets_store_inferior_registers,
5765 unless ALL is non-zero.
5766 Otherwise, REGNO specifies which register (so we can save time). */
5767 static void
5768 usr_store_inferior_registers (const struct regs_info *regs_info,
5769 struct regcache *regcache, int regno, int all)
5770 {
5771 struct usrregs_info *usr = regs_info->usrregs;
5772
5773 if (regno == -1)
5774 {
5775 for (regno = 0; regno < usr->num_regs; regno++)
5776 if (all || !linux_register_in_regsets (regs_info, regno))
5777 store_register (usr, regcache, regno);
5778 }
5779 else
5780 store_register (usr, regcache, regno);
5781 }
5782
5783 #else /* !HAVE_LINUX_USRREGS */
5784
5785 #define usr_fetch_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
5786 #define usr_store_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
5787
5788 #endif
5789
5790
5791 static void
5792 linux_fetch_registers (struct regcache *regcache, int regno)
5793 {
5794 int use_regsets;
5795 int all = 0;
5796 const struct regs_info *regs_info = (*the_low_target.regs_info) ();
5797
5798 if (regno == -1)
5799 {
5800 if (the_low_target.fetch_register != NULL
5801 && regs_info->usrregs != NULL)
5802 for (regno = 0; regno < regs_info->usrregs->num_regs; regno++)
5803 (*the_low_target.fetch_register) (regcache, regno);
5804
5805 all = regsets_fetch_inferior_registers (regs_info->regsets_info, regcache);
5806 if (regs_info->usrregs != NULL)
5807 usr_fetch_inferior_registers (regs_info, regcache, -1, all);
5808 }
5809 else
5810 {
5811 if (the_low_target.fetch_register != NULL
5812 && (*the_low_target.fetch_register) (regcache, regno))
5813 return;
5814
5815 use_regsets = linux_register_in_regsets (regs_info, regno);
5816 if (use_regsets)
5817 all = regsets_fetch_inferior_registers (regs_info->regsets_info,
5818 regcache);
5819 if ((!use_regsets || all) && regs_info->usrregs != NULL)
5820 usr_fetch_inferior_registers (regs_info, regcache, regno, 1);
5821 }
5822 }
5823
5824 static void
5825 linux_store_registers (struct regcache *regcache, int regno)
5826 {
5827 int use_regsets;
5828 int all = 0;
5829 const struct regs_info *regs_info = (*the_low_target.regs_info) ();
5830
5831 if (regno == -1)
5832 {
5833 all = regsets_store_inferior_registers (regs_info->regsets_info,
5834 regcache);
5835 if (regs_info->usrregs != NULL)
5836 usr_store_inferior_registers (regs_info, regcache, regno, all);
5837 }
5838 else
5839 {
5840 use_regsets = linux_register_in_regsets (regs_info, regno);
5841 if (use_regsets)
5842 all = regsets_store_inferior_registers (regs_info->regsets_info,
5843 regcache);
5844 if ((!use_regsets || all) && regs_info->usrregs != NULL)
5845 usr_store_inferior_registers (regs_info, regcache, regno, 1);
5846 }
5847 }
5848
5849
5850 /* Copy LEN bytes from inferior's memory starting at MEMADDR
5851 to debugger memory starting at MYADDR. */
5852
5853 static int
5854 linux_read_memory (CORE_ADDR memaddr, unsigned char *myaddr, int len)
5855 {
5856 int pid = lwpid_of (current_thread);
5857 PTRACE_XFER_TYPE *buffer;
5858 CORE_ADDR addr;
5859 int count;
5860 char filename[64];
5861 int i;
5862 int ret;
5863 int fd;
5864
5865 /* Try using /proc. Don't bother for one word. */
5866 if (len >= 3 * sizeof (long))
5867 {
5868 int bytes;
5869
5870 /* We could keep this file open and cache it - possibly one per
5871 thread. That requires some juggling, but is even faster. */
5872 sprintf (filename, "/proc/%d/mem", pid);
5873 fd = open (filename, O_RDONLY | O_LARGEFILE);
5874 if (fd == -1)
5875 goto no_proc;
5876
5877 /* If pread64 is available, use it. It's faster if the kernel
5878 supports it (only one syscall), and it's 64-bit safe even on
5879 32-bit platforms (for instance, SPARC debugging a SPARC64
5880 application). */
5881 #ifdef HAVE_PREAD64
5882 bytes = pread64 (fd, myaddr, len, memaddr);
5883 #else
5884 bytes = -1;
5885 if (lseek (fd, memaddr, SEEK_SET) != -1)
5886 bytes = read (fd, myaddr, len);
5887 #endif
5888
5889 close (fd);
5890 if (bytes == len)
5891 return 0;
5892
5893 /* Some data was read, we'll try to get the rest with ptrace. */
5894 if (bytes > 0)
5895 {
5896 memaddr += bytes;
5897 myaddr += bytes;
5898 len -= bytes;
5899 }
5900 }
5901
5902 no_proc:
5903 /* Round starting address down to longword boundary. */
5904 addr = memaddr & -(CORE_ADDR) sizeof (PTRACE_XFER_TYPE);
5905 /* Round ending address up; get number of longwords that makes. */
5906 count = ((((memaddr + len) - addr) + sizeof (PTRACE_XFER_TYPE) - 1)
5907 / sizeof (PTRACE_XFER_TYPE));
5908 /* Allocate buffer of that many longwords. */
5909 buffer = XALLOCAVEC (PTRACE_XFER_TYPE, count);
5910
5911 /* Read all the longwords */
5912 errno = 0;
5913 for (i = 0; i < count; i++, addr += sizeof (PTRACE_XFER_TYPE))
5914 {
5915 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5916 about coercing an 8 byte integer to a 4 byte pointer. */
5917 buffer[i] = ptrace (PTRACE_PEEKTEXT, pid,
5918 (PTRACE_TYPE_ARG3) (uintptr_t) addr,
5919 (PTRACE_TYPE_ARG4) 0);
5920 if (errno)
5921 break;
5922 }
5923 ret = errno;
5924
5925 /* Copy appropriate bytes out of the buffer. */
5926 if (i > 0)
5927 {
5928 i *= sizeof (PTRACE_XFER_TYPE);
5929 i -= memaddr & (sizeof (PTRACE_XFER_TYPE) - 1);
5930 memcpy (myaddr,
5931 (char *) buffer + (memaddr & (sizeof (PTRACE_XFER_TYPE) - 1)),
5932 i < len ? i : len);
5933 }
5934
5935 return ret;
5936 }
5937
5938 /* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
5939 memory at MEMADDR. On failure (cannot write to the inferior)
5940 returns the value of errno. Always succeeds if LEN is zero. */
5941
5942 static int
5943 linux_write_memory (CORE_ADDR memaddr, const unsigned char *myaddr, int len)
5944 {
5945 int i;
5946 /* Round starting address down to longword boundary. */
5947 CORE_ADDR addr = memaddr & -(CORE_ADDR) sizeof (PTRACE_XFER_TYPE);
5948 /* Round ending address up; get number of longwords that makes. */
5949 int count
5950 = (((memaddr + len) - addr) + sizeof (PTRACE_XFER_TYPE) - 1)
5951 / sizeof (PTRACE_XFER_TYPE);
5952
5953 /* Allocate buffer of that many longwords. */
5954 PTRACE_XFER_TYPE *buffer = XALLOCAVEC (PTRACE_XFER_TYPE, count);
5955
5956 int pid = lwpid_of (current_thread);
5957
5958 if (len == 0)
5959 {
5960 /* Zero length write always succeeds. */
5961 return 0;
5962 }
5963
5964 if (debug_threads)
5965 {
5966 /* Dump up to four bytes. */
5967 char str[4 * 2 + 1];
5968 char *p = str;
5969 int dump = len < 4 ? len : 4;
5970
5971 for (i = 0; i < dump; i++)
5972 {
5973 sprintf (p, "%02x", myaddr[i]);
5974 p += 2;
5975 }
5976 *p = '\0';
5977
5978 debug_printf ("Writing %s to 0x%08lx in process %d\n",
5979 str, (long) memaddr, pid);
5980 }
5981
5982 /* Fill start and end extra bytes of buffer with existing memory data. */
5983
5984 errno = 0;
5985 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5986 about coercing an 8 byte integer to a 4 byte pointer. */
5987 buffer[0] = ptrace (PTRACE_PEEKTEXT, pid,
5988 (PTRACE_TYPE_ARG3) (uintptr_t) addr,
5989 (PTRACE_TYPE_ARG4) 0);
5990 if (errno)
5991 return errno;
5992
5993 if (count > 1)
5994 {
5995 errno = 0;
5996 buffer[count - 1]
5997 = ptrace (PTRACE_PEEKTEXT, pid,
5998 /* Coerce to a uintptr_t first to avoid potential gcc warning
5999 about coercing an 8 byte integer to a 4 byte pointer. */
6000 (PTRACE_TYPE_ARG3) (uintptr_t) (addr + (count - 1)
6001 * sizeof (PTRACE_XFER_TYPE)),
6002 (PTRACE_TYPE_ARG4) 0);
6003 if (errno)
6004 return errno;
6005 }
6006
6007 /* Copy data to be written over corresponding part of buffer. */
6008
6009 memcpy ((char *) buffer + (memaddr & (sizeof (PTRACE_XFER_TYPE) - 1)),
6010 myaddr, len);
6011
6012 /* Write the entire buffer. */
6013
6014 for (i = 0; i < count; i++, addr += sizeof (PTRACE_XFER_TYPE))
6015 {
6016 errno = 0;
6017 ptrace (PTRACE_POKETEXT, pid,
6018 /* Coerce to a uintptr_t first to avoid potential gcc warning
6019 about coercing an 8 byte integer to a 4 byte pointer. */
6020 (PTRACE_TYPE_ARG3) (uintptr_t) addr,
6021 (PTRACE_TYPE_ARG4) buffer[i]);
6022 if (errno)
6023 return errno;
6024 }
6025
6026 return 0;
6027 }
6028
6029 static void
6030 linux_look_up_symbols (void)
6031 {
6032 #ifdef USE_THREAD_DB
6033 struct process_info *proc = current_process ();
6034
6035 if (proc->priv->thread_db != NULL)
6036 return;
6037
6038 thread_db_init ();
6039 #endif
6040 }
6041
6042 static void
6043 linux_request_interrupt (void)
6044 {
6045 /* Send a SIGINT to the process group. This acts just like the user
6046 typed a ^C on the controlling terminal. */
6047 kill (-signal_pid, SIGINT);
6048 }
6049
6050 /* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
6051 to debugger memory starting at MYADDR. */
6052
6053 static int
6054 linux_read_auxv (CORE_ADDR offset, unsigned char *myaddr, unsigned int len)
6055 {
6056 char filename[PATH_MAX];
6057 int fd, n;
6058 int pid = lwpid_of (current_thread);
6059
6060 xsnprintf (filename, sizeof filename, "/proc/%d/auxv", pid);
6061
6062 fd = open (filename, O_RDONLY);
6063 if (fd < 0)
6064 return -1;
6065
6066 if (offset != (CORE_ADDR) 0
6067 && lseek (fd, (off_t) offset, SEEK_SET) != (off_t) offset)
6068 n = -1;
6069 else
6070 n = read (fd, myaddr, len);
6071
6072 close (fd);
6073
6074 return n;
6075 }
6076
6077 /* These breakpoint and watchpoint related wrapper functions simply
6078 pass on the function call if the target has registered a
6079 corresponding function. */
6080
6081 static int
6082 linux_supports_z_point_type (char z_type)
6083 {
6084 return (the_low_target.supports_z_point_type != NULL
6085 && the_low_target.supports_z_point_type (z_type));
6086 }
6087
6088 static int
6089 linux_insert_point (enum raw_bkpt_type type, CORE_ADDR addr,
6090 int size, struct raw_breakpoint *bp)
6091 {
6092 if (type == raw_bkpt_type_sw)
6093 return insert_memory_breakpoint (bp);
6094 else if (the_low_target.insert_point != NULL)
6095 return the_low_target.insert_point (type, addr, size, bp);
6096 else
6097 /* Unsupported (see target.h). */
6098 return 1;
6099 }
6100
6101 static int
6102 linux_remove_point (enum raw_bkpt_type type, CORE_ADDR addr,
6103 int size, struct raw_breakpoint *bp)
6104 {
6105 if (type == raw_bkpt_type_sw)
6106 return remove_memory_breakpoint (bp);
6107 else if (the_low_target.remove_point != NULL)
6108 return the_low_target.remove_point (type, addr, size, bp);
6109 else
6110 /* Unsupported (see target.h). */
6111 return 1;
6112 }
6113
6114 /* Implement the to_stopped_by_sw_breakpoint target_ops
6115 method. */
6116
6117 static int
6118 linux_stopped_by_sw_breakpoint (void)
6119 {
6120 struct lwp_info *lwp = get_thread_lwp (current_thread);
6121
6122 return (lwp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT);
6123 }
6124
6125 /* Implement the to_supports_stopped_by_sw_breakpoint target_ops
6126 method. */
6127
6128 static int
6129 linux_supports_stopped_by_sw_breakpoint (void)
6130 {
6131 return USE_SIGTRAP_SIGINFO;
6132 }
6133
6134 /* Implement the to_stopped_by_hw_breakpoint target_ops
6135 method. */
6136
6137 static int
6138 linux_stopped_by_hw_breakpoint (void)
6139 {
6140 struct lwp_info *lwp = get_thread_lwp (current_thread);
6141
6142 return (lwp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT);
6143 }
6144
6145 /* Implement the to_supports_stopped_by_hw_breakpoint target_ops
6146 method. */
6147
6148 static int
6149 linux_supports_stopped_by_hw_breakpoint (void)
6150 {
6151 return USE_SIGTRAP_SIGINFO;
6152 }
6153
6154 /* Implement the supports_hardware_single_step target_ops method. */
6155
6156 static int
6157 linux_supports_hardware_single_step (void)
6158 {
6159 return can_hardware_single_step ();
6160 }
6161
6162 static int
6163 linux_supports_software_single_step (void)
6164 {
6165 return can_software_single_step ();
6166 }
6167
6168 static int
6169 linux_stopped_by_watchpoint (void)
6170 {
6171 struct lwp_info *lwp = get_thread_lwp (current_thread);
6172
6173 return lwp->stop_reason == TARGET_STOPPED_BY_WATCHPOINT;
6174 }
6175
6176 static CORE_ADDR
6177 linux_stopped_data_address (void)
6178 {
6179 struct lwp_info *lwp = get_thread_lwp (current_thread);
6180
6181 return lwp->stopped_data_address;
6182 }
6183
6184 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
6185 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
6186 && defined(PT_TEXT_END_ADDR)
6187
6188 /* This is only used for targets that define PT_TEXT_ADDR,
6189 PT_DATA_ADDR and PT_TEXT_END_ADDR. If those are not defined, supposedly
6190 the target has different ways of acquiring this information, like
6191 loadmaps. */
6192
6193 /* Under uClinux, programs are loaded at non-zero offsets, which we need
6194 to tell gdb about. */
6195
6196 static int
6197 linux_read_offsets (CORE_ADDR *text_p, CORE_ADDR *data_p)
6198 {
6199 unsigned long text, text_end, data;
6200 int pid = lwpid_of (current_thread);
6201
6202 errno = 0;
6203
6204 text = ptrace (PTRACE_PEEKUSER, pid, (PTRACE_TYPE_ARG3) PT_TEXT_ADDR,
6205 (PTRACE_TYPE_ARG4) 0);
6206 text_end = ptrace (PTRACE_PEEKUSER, pid, (PTRACE_TYPE_ARG3) PT_TEXT_END_ADDR,
6207 (PTRACE_TYPE_ARG4) 0);
6208 data = ptrace (PTRACE_PEEKUSER, pid, (PTRACE_TYPE_ARG3) PT_DATA_ADDR,
6209 (PTRACE_TYPE_ARG4) 0);
6210
6211 if (errno == 0)
6212 {
6213 /* Both text and data offsets produced at compile-time (and so
6214 used by gdb) are relative to the beginning of the program,
6215 with the data segment immediately following the text segment.
6216 However, the actual runtime layout in memory may put the data
6217 somewhere else, so when we send gdb a data base-address, we
6218 use the real data base address and subtract the compile-time
6219 data base-address from it (which is just the length of the
6220 text segment). BSS immediately follows data in both
6221 cases. */
6222 *text_p = text;
6223 *data_p = data - (text_end - text);
6224
6225 return 1;
6226 }
6227 return 0;
6228 }
6229 #endif
6230
6231 static int
6232 linux_qxfer_osdata (const char *annex,
6233 unsigned char *readbuf, unsigned const char *writebuf,
6234 CORE_ADDR offset, int len)
6235 {
6236 return linux_common_xfer_osdata (annex, readbuf, offset, len);
6237 }
6238
6239 /* Convert a native/host siginfo object, into/from the siginfo in the
6240 layout of the inferiors' architecture. */
6241
6242 static void
6243 siginfo_fixup (siginfo_t *siginfo, gdb_byte *inf_siginfo, int direction)
6244 {
6245 int done = 0;
6246
6247 if (the_low_target.siginfo_fixup != NULL)
6248 done = the_low_target.siginfo_fixup (siginfo, inf_siginfo, direction);
6249
6250 /* If there was no callback, or the callback didn't do anything,
6251 then just do a straight memcpy. */
6252 if (!done)
6253 {
6254 if (direction == 1)
6255 memcpy (siginfo, inf_siginfo, sizeof (siginfo_t));
6256 else
6257 memcpy (inf_siginfo, siginfo, sizeof (siginfo_t));
6258 }
6259 }
6260
6261 static int
6262 linux_xfer_siginfo (const char *annex, unsigned char *readbuf,
6263 unsigned const char *writebuf, CORE_ADDR offset, int len)
6264 {
6265 int pid;
6266 siginfo_t siginfo;
6267 gdb_byte inf_siginfo[sizeof (siginfo_t)];
6268
6269 if (current_thread == NULL)
6270 return -1;
6271
6272 pid = lwpid_of (current_thread);
6273
6274 if (debug_threads)
6275 debug_printf ("%s siginfo for lwp %d.\n",
6276 readbuf != NULL ? "Reading" : "Writing",
6277 pid);
6278
6279 if (offset >= sizeof (siginfo))
6280 return -1;
6281
6282 if (ptrace (PTRACE_GETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo) != 0)
6283 return -1;
6284
6285 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
6286 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
6287 inferior with a 64-bit GDBSERVER should look the same as debugging it
6288 with a 32-bit GDBSERVER, we need to convert it. */
6289 siginfo_fixup (&siginfo, inf_siginfo, 0);
6290
6291 if (offset + len > sizeof (siginfo))
6292 len = sizeof (siginfo) - offset;
6293
6294 if (readbuf != NULL)
6295 memcpy (readbuf, inf_siginfo + offset, len);
6296 else
6297 {
6298 memcpy (inf_siginfo + offset, writebuf, len);
6299
6300 /* Convert back to ptrace layout before flushing it out. */
6301 siginfo_fixup (&siginfo, inf_siginfo, 1);
6302
6303 if (ptrace (PTRACE_SETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo) != 0)
6304 return -1;
6305 }
6306
6307 return len;
6308 }
6309
6310 /* SIGCHLD handler that serves two purposes: In non-stop/async mode,
6311 so we notice when children change state; as the handler for the
6312 sigsuspend in my_waitpid. */
6313
6314 static void
6315 sigchld_handler (int signo)
6316 {
6317 int old_errno = errno;
6318
6319 if (debug_threads)
6320 {
6321 do
6322 {
6323 /* fprintf is not async-signal-safe, so call write
6324 directly. */
6325 if (write (2, "sigchld_handler\n",
6326 sizeof ("sigchld_handler\n") - 1) < 0)
6327 break; /* just ignore */
6328 } while (0);
6329 }
6330
6331 if (target_is_async_p ())
6332 async_file_mark (); /* trigger a linux_wait */
6333
6334 errno = old_errno;
6335 }
6336
6337 static int
6338 linux_supports_non_stop (void)
6339 {
6340 return 1;
6341 }
6342
6343 static int
6344 linux_async (int enable)
6345 {
6346 int previous = target_is_async_p ();
6347
6348 if (debug_threads)
6349 debug_printf ("linux_async (%d), previous=%d\n",
6350 enable, previous);
6351
6352 if (previous != enable)
6353 {
6354 sigset_t mask;
6355 sigemptyset (&mask);
6356 sigaddset (&mask, SIGCHLD);
6357
6358 sigprocmask (SIG_BLOCK, &mask, NULL);
6359
6360 if (enable)
6361 {
6362 if (pipe (linux_event_pipe) == -1)
6363 {
6364 linux_event_pipe[0] = -1;
6365 linux_event_pipe[1] = -1;
6366 sigprocmask (SIG_UNBLOCK, &mask, NULL);
6367
6368 warning ("creating event pipe failed.");
6369 return previous;
6370 }
6371
6372 fcntl (linux_event_pipe[0], F_SETFL, O_NONBLOCK);
6373 fcntl (linux_event_pipe[1], F_SETFL, O_NONBLOCK);
6374
6375 /* Register the event loop handler. */
6376 add_file_handler (linux_event_pipe[0],
6377 handle_target_event, NULL);
6378
6379 /* Always trigger a linux_wait. */
6380 async_file_mark ();
6381 }
6382 else
6383 {
6384 delete_file_handler (linux_event_pipe[0]);
6385
6386 close (linux_event_pipe[0]);
6387 close (linux_event_pipe[1]);
6388 linux_event_pipe[0] = -1;
6389 linux_event_pipe[1] = -1;
6390 }
6391
6392 sigprocmask (SIG_UNBLOCK, &mask, NULL);
6393 }
6394
6395 return previous;
6396 }
6397
6398 static int
6399 linux_start_non_stop (int nonstop)
6400 {
6401 /* Register or unregister from event-loop accordingly. */
6402 linux_async (nonstop);
6403
6404 if (target_is_async_p () != (nonstop != 0))
6405 return -1;
6406
6407 return 0;
6408 }
6409
6410 static int
6411 linux_supports_multi_process (void)
6412 {
6413 return 1;
6414 }
6415
6416 /* Check if fork events are supported. */
6417
6418 static int
6419 linux_supports_fork_events (void)
6420 {
6421 return linux_supports_tracefork ();
6422 }
6423
6424 /* Check if vfork events are supported. */
6425
6426 static int
6427 linux_supports_vfork_events (void)
6428 {
6429 return linux_supports_tracefork ();
6430 }
6431
6432 /* Check if exec events are supported. */
6433
6434 static int
6435 linux_supports_exec_events (void)
6436 {
6437 return linux_supports_traceexec ();
6438 }
6439
6440 /* Callback for 'find_inferior'. Set the (possibly changed) ptrace
6441 options for the specified lwp. */
6442
6443 static int
6444 reset_lwp_ptrace_options_callback (thread_info *thread, void *args)
6445 {
6446 struct lwp_info *lwp = get_thread_lwp (thread);
6447
6448 if (!lwp->stopped)
6449 {
6450 /* Stop the lwp so we can modify its ptrace options. */
6451 lwp->must_set_ptrace_flags = 1;
6452 linux_stop_lwp (lwp);
6453 }
6454 else
6455 {
6456 /* Already stopped; go ahead and set the ptrace options. */
6457 struct process_info *proc = find_process_pid (pid_of (thread));
6458 int options = linux_low_ptrace_options (proc->attached);
6459
6460 linux_enable_event_reporting (lwpid_of (thread), options);
6461 lwp->must_set_ptrace_flags = 0;
6462 }
6463
6464 return 0;
6465 }
6466
6467 /* Target hook for 'handle_new_gdb_connection'. Causes a reset of the
6468 ptrace flags for all inferiors. This is in case the new GDB connection
6469 doesn't support the same set of events that the previous one did. */
6470
6471 static void
6472 linux_handle_new_gdb_connection (void)
6473 {
6474 pid_t pid;
6475
6476 /* Request that all the lwps reset their ptrace options. */
6477 find_inferior (&all_threads, reset_lwp_ptrace_options_callback , &pid);
6478 }
6479
6480 static int
6481 linux_supports_disable_randomization (void)
6482 {
6483 #ifdef HAVE_PERSONALITY
6484 return 1;
6485 #else
6486 return 0;
6487 #endif
6488 }
6489
6490 static int
6491 linux_supports_agent (void)
6492 {
6493 return 1;
6494 }
6495
6496 static int
6497 linux_supports_range_stepping (void)
6498 {
6499 if (can_software_single_step ())
6500 return 1;
6501 if (*the_low_target.supports_range_stepping == NULL)
6502 return 0;
6503
6504 return (*the_low_target.supports_range_stepping) ();
6505 }
6506
6507 /* Enumerate spufs IDs for process PID. */
6508 static int
6509 spu_enumerate_spu_ids (long pid, unsigned char *buf, CORE_ADDR offset, int len)
6510 {
6511 int pos = 0;
6512 int written = 0;
6513 char path[128];
6514 DIR *dir;
6515 struct dirent *entry;
6516
6517 sprintf (path, "/proc/%ld/fd", pid);
6518 dir = opendir (path);
6519 if (!dir)
6520 return -1;
6521
6522 rewinddir (dir);
6523 while ((entry = readdir (dir)) != NULL)
6524 {
6525 struct stat st;
6526 struct statfs stfs;
6527 int fd;
6528
6529 fd = atoi (entry->d_name);
6530 if (!fd)
6531 continue;
6532
6533 sprintf (path, "/proc/%ld/fd/%d", pid, fd);
6534 if (stat (path, &st) != 0)
6535 continue;
6536 if (!S_ISDIR (st.st_mode))
6537 continue;
6538
6539 if (statfs (path, &stfs) != 0)
6540 continue;
6541 if (stfs.f_type != SPUFS_MAGIC)
6542 continue;
6543
6544 if (pos >= offset && pos + 4 <= offset + len)
6545 {
6546 *(unsigned int *)(buf + pos - offset) = fd;
6547 written += 4;
6548 }
6549 pos += 4;
6550 }
6551
6552 closedir (dir);
6553 return written;
6554 }
6555
6556 /* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
6557 object type, using the /proc file system. */
6558 static int
6559 linux_qxfer_spu (const char *annex, unsigned char *readbuf,
6560 unsigned const char *writebuf,
6561 CORE_ADDR offset, int len)
6562 {
6563 long pid = lwpid_of (current_thread);
6564 char buf[128];
6565 int fd = 0;
6566 int ret = 0;
6567
6568 if (!writebuf && !readbuf)
6569 return -1;
6570
6571 if (!*annex)
6572 {
6573 if (!readbuf)
6574 return -1;
6575 else
6576 return spu_enumerate_spu_ids (pid, readbuf, offset, len);
6577 }
6578
6579 sprintf (buf, "/proc/%ld/fd/%s", pid, annex);
6580 fd = open (buf, writebuf? O_WRONLY : O_RDONLY);
6581 if (fd <= 0)
6582 return -1;
6583
6584 if (offset != 0
6585 && lseek (fd, (off_t) offset, SEEK_SET) != (off_t) offset)
6586 {
6587 close (fd);
6588 return 0;
6589 }
6590
6591 if (writebuf)
6592 ret = write (fd, writebuf, (size_t) len);
6593 else
6594 ret = read (fd, readbuf, (size_t) len);
6595
6596 close (fd);
6597 return ret;
6598 }
6599
6600 #if defined PT_GETDSBT || defined PTRACE_GETFDPIC
6601 struct target_loadseg
6602 {
6603 /* Core address to which the segment is mapped. */
6604 Elf32_Addr addr;
6605 /* VMA recorded in the program header. */
6606 Elf32_Addr p_vaddr;
6607 /* Size of this segment in memory. */
6608 Elf32_Word p_memsz;
6609 };
6610
6611 # if defined PT_GETDSBT
6612 struct target_loadmap
6613 {
6614 /* Protocol version number, must be zero. */
6615 Elf32_Word version;
6616 /* Pointer to the DSBT table, its size, and the DSBT index. */
6617 unsigned *dsbt_table;
6618 unsigned dsbt_size, dsbt_index;
6619 /* Number of segments in this map. */
6620 Elf32_Word nsegs;
6621 /* The actual memory map. */
6622 struct target_loadseg segs[/*nsegs*/];
6623 };
6624 # define LINUX_LOADMAP PT_GETDSBT
6625 # define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
6626 # define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
6627 # else
6628 struct target_loadmap
6629 {
6630 /* Protocol version number, must be zero. */
6631 Elf32_Half version;
6632 /* Number of segments in this map. */
6633 Elf32_Half nsegs;
6634 /* The actual memory map. */
6635 struct target_loadseg segs[/*nsegs*/];
6636 };
6637 # define LINUX_LOADMAP PTRACE_GETFDPIC
6638 # define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
6639 # define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
6640 # endif
6641
6642 static int
6643 linux_read_loadmap (const char *annex, CORE_ADDR offset,
6644 unsigned char *myaddr, unsigned int len)
6645 {
6646 int pid = lwpid_of (current_thread);
6647 int addr = -1;
6648 struct target_loadmap *data = NULL;
6649 unsigned int actual_length, copy_length;
6650
6651 if (strcmp (annex, "exec") == 0)
6652 addr = (int) LINUX_LOADMAP_EXEC;
6653 else if (strcmp (annex, "interp") == 0)
6654 addr = (int) LINUX_LOADMAP_INTERP;
6655 else
6656 return -1;
6657
6658 if (ptrace (LINUX_LOADMAP, pid, addr, &data) != 0)
6659 return -1;
6660
6661 if (data == NULL)
6662 return -1;
6663
6664 actual_length = sizeof (struct target_loadmap)
6665 + sizeof (struct target_loadseg) * data->nsegs;
6666
6667 if (offset < 0 || offset > actual_length)
6668 return -1;
6669
6670 copy_length = actual_length - offset < len ? actual_length - offset : len;
6671 memcpy (myaddr, (char *) data + offset, copy_length);
6672 return copy_length;
6673 }
6674 #else
6675 # define linux_read_loadmap NULL
6676 #endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
6677
6678 static void
6679 linux_process_qsupported (char **features, int count)
6680 {
6681 if (the_low_target.process_qsupported != NULL)
6682 the_low_target.process_qsupported (features, count);
6683 }
6684
6685 static int
6686 linux_supports_catch_syscall (void)
6687 {
6688 return (the_low_target.get_syscall_trapinfo != NULL
6689 && linux_supports_tracesysgood ());
6690 }
6691
6692 static int
6693 linux_get_ipa_tdesc_idx (void)
6694 {
6695 if (the_low_target.get_ipa_tdesc_idx == NULL)
6696 return 0;
6697
6698 return (*the_low_target.get_ipa_tdesc_idx) ();
6699 }
6700
6701 static int
6702 linux_supports_tracepoints (void)
6703 {
6704 if (*the_low_target.supports_tracepoints == NULL)
6705 return 0;
6706
6707 return (*the_low_target.supports_tracepoints) ();
6708 }
6709
6710 static CORE_ADDR
6711 linux_read_pc (struct regcache *regcache)
6712 {
6713 if (the_low_target.get_pc == NULL)
6714 return 0;
6715
6716 return (*the_low_target.get_pc) (regcache);
6717 }
6718
6719 static void
6720 linux_write_pc (struct regcache *regcache, CORE_ADDR pc)
6721 {
6722 gdb_assert (the_low_target.set_pc != NULL);
6723
6724 (*the_low_target.set_pc) (regcache, pc);
6725 }
6726
6727 static int
6728 linux_thread_stopped (struct thread_info *thread)
6729 {
6730 return get_thread_lwp (thread)->stopped;
6731 }
6732
6733 /* This exposes stop-all-threads functionality to other modules. */
6734
6735 static void
6736 linux_pause_all (int freeze)
6737 {
6738 stop_all_lwps (freeze, NULL);
6739 }
6740
6741 /* This exposes unstop-all-threads functionality to other gdbserver
6742 modules. */
6743
6744 static void
6745 linux_unpause_all (int unfreeze)
6746 {
6747 unstop_all_lwps (unfreeze, NULL);
6748 }
6749
6750 static int
6751 linux_prepare_to_access_memory (void)
6752 {
6753 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6754 running LWP. */
6755 if (non_stop)
6756 linux_pause_all (1);
6757 return 0;
6758 }
6759
6760 static void
6761 linux_done_accessing_memory (void)
6762 {
6763 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6764 running LWP. */
6765 if (non_stop)
6766 linux_unpause_all (1);
6767 }
6768
6769 static int
6770 linux_install_fast_tracepoint_jump_pad (CORE_ADDR tpoint, CORE_ADDR tpaddr,
6771 CORE_ADDR collector,
6772 CORE_ADDR lockaddr,
6773 ULONGEST orig_size,
6774 CORE_ADDR *jump_entry,
6775 CORE_ADDR *trampoline,
6776 ULONGEST *trampoline_size,
6777 unsigned char *jjump_pad_insn,
6778 ULONGEST *jjump_pad_insn_size,
6779 CORE_ADDR *adjusted_insn_addr,
6780 CORE_ADDR *adjusted_insn_addr_end,
6781 char *err)
6782 {
6783 return (*the_low_target.install_fast_tracepoint_jump_pad)
6784 (tpoint, tpaddr, collector, lockaddr, orig_size,
6785 jump_entry, trampoline, trampoline_size,
6786 jjump_pad_insn, jjump_pad_insn_size,
6787 adjusted_insn_addr, adjusted_insn_addr_end,
6788 err);
6789 }
6790
6791 static struct emit_ops *
6792 linux_emit_ops (void)
6793 {
6794 if (the_low_target.emit_ops != NULL)
6795 return (*the_low_target.emit_ops) ();
6796 else
6797 return NULL;
6798 }
6799
6800 static int
6801 linux_get_min_fast_tracepoint_insn_len (void)
6802 {
6803 return (*the_low_target.get_min_fast_tracepoint_insn_len) ();
6804 }
6805
6806 /* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
6807
6808 static int
6809 get_phdr_phnum_from_proc_auxv (const int pid, const int is_elf64,
6810 CORE_ADDR *phdr_memaddr, int *num_phdr)
6811 {
6812 char filename[PATH_MAX];
6813 int fd;
6814 const int auxv_size = is_elf64
6815 ? sizeof (Elf64_auxv_t) : sizeof (Elf32_auxv_t);
6816 char buf[sizeof (Elf64_auxv_t)]; /* The larger of the two. */
6817
6818 xsnprintf (filename, sizeof filename, "/proc/%d/auxv", pid);
6819
6820 fd = open (filename, O_RDONLY);
6821 if (fd < 0)
6822 return 1;
6823
6824 *phdr_memaddr = 0;
6825 *num_phdr = 0;
6826 while (read (fd, buf, auxv_size) == auxv_size
6827 && (*phdr_memaddr == 0 || *num_phdr == 0))
6828 {
6829 if (is_elf64)
6830 {
6831 Elf64_auxv_t *const aux = (Elf64_auxv_t *) buf;
6832
6833 switch (aux->a_type)
6834 {
6835 case AT_PHDR:
6836 *phdr_memaddr = aux->a_un.a_val;
6837 break;
6838 case AT_PHNUM:
6839 *num_phdr = aux->a_un.a_val;
6840 break;
6841 }
6842 }
6843 else
6844 {
6845 Elf32_auxv_t *const aux = (Elf32_auxv_t *) buf;
6846
6847 switch (aux->a_type)
6848 {
6849 case AT_PHDR:
6850 *phdr_memaddr = aux->a_un.a_val;
6851 break;
6852 case AT_PHNUM:
6853 *num_phdr = aux->a_un.a_val;
6854 break;
6855 }
6856 }
6857 }
6858
6859 close (fd);
6860
6861 if (*phdr_memaddr == 0 || *num_phdr == 0)
6862 {
6863 warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
6864 "phdr_memaddr = %ld, phdr_num = %d",
6865 (long) *phdr_memaddr, *num_phdr);
6866 return 2;
6867 }
6868
6869 return 0;
6870 }
6871
6872 /* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
6873
6874 static CORE_ADDR
6875 get_dynamic (const int pid, const int is_elf64)
6876 {
6877 CORE_ADDR phdr_memaddr, relocation;
6878 int num_phdr, i;
6879 unsigned char *phdr_buf;
6880 const int phdr_size = is_elf64 ? sizeof (Elf64_Phdr) : sizeof (Elf32_Phdr);
6881
6882 if (get_phdr_phnum_from_proc_auxv (pid, is_elf64, &phdr_memaddr, &num_phdr))
6883 return 0;
6884
6885 gdb_assert (num_phdr < 100); /* Basic sanity check. */
6886 phdr_buf = (unsigned char *) alloca (num_phdr * phdr_size);
6887
6888 if (linux_read_memory (phdr_memaddr, phdr_buf, num_phdr * phdr_size))
6889 return 0;
6890
6891 /* Compute relocation: it is expected to be 0 for "regular" executables,
6892 non-zero for PIE ones. */
6893 relocation = -1;
6894 for (i = 0; relocation == -1 && i < num_phdr; i++)
6895 if (is_elf64)
6896 {
6897 Elf64_Phdr *const p = (Elf64_Phdr *) (phdr_buf + i * phdr_size);
6898
6899 if (p->p_type == PT_PHDR)
6900 relocation = phdr_memaddr - p->p_vaddr;
6901 }
6902 else
6903 {
6904 Elf32_Phdr *const p = (Elf32_Phdr *) (phdr_buf + i * phdr_size);
6905
6906 if (p->p_type == PT_PHDR)
6907 relocation = phdr_memaddr - p->p_vaddr;
6908 }
6909
6910 if (relocation == -1)
6911 {
6912 /* PT_PHDR is optional, but necessary for PIE in general. Fortunately
6913 any real world executables, including PIE executables, have always
6914 PT_PHDR present. PT_PHDR is not present in some shared libraries or
6915 in fpc (Free Pascal 2.4) binaries but neither of those have a need for
6916 or present DT_DEBUG anyway (fpc binaries are statically linked).
6917
6918 Therefore if there exists DT_DEBUG there is always also PT_PHDR.
6919
6920 GDB could find RELOCATION also from AT_ENTRY - e_entry. */
6921
6922 return 0;
6923 }
6924
6925 for (i = 0; i < num_phdr; i++)
6926 {
6927 if (is_elf64)
6928 {
6929 Elf64_Phdr *const p = (Elf64_Phdr *) (phdr_buf + i * phdr_size);
6930
6931 if (p->p_type == PT_DYNAMIC)
6932 return p->p_vaddr + relocation;
6933 }
6934 else
6935 {
6936 Elf32_Phdr *const p = (Elf32_Phdr *) (phdr_buf + i * phdr_size);
6937
6938 if (p->p_type == PT_DYNAMIC)
6939 return p->p_vaddr + relocation;
6940 }
6941 }
6942
6943 return 0;
6944 }
6945
6946 /* Return &_r_debug in the inferior, or -1 if not present. Return value
6947 can be 0 if the inferior does not yet have the library list initialized.
6948 We look for DT_MIPS_RLD_MAP first. MIPS executables use this instead of
6949 DT_DEBUG, although they sometimes contain an unused DT_DEBUG entry too. */
6950
6951 static CORE_ADDR
6952 get_r_debug (const int pid, const int is_elf64)
6953 {
6954 CORE_ADDR dynamic_memaddr;
6955 const int dyn_size = is_elf64 ? sizeof (Elf64_Dyn) : sizeof (Elf32_Dyn);
6956 unsigned char buf[sizeof (Elf64_Dyn)]; /* The larger of the two. */
6957 CORE_ADDR map = -1;
6958
6959 dynamic_memaddr = get_dynamic (pid, is_elf64);
6960 if (dynamic_memaddr == 0)
6961 return map;
6962
6963 while (linux_read_memory (dynamic_memaddr, buf, dyn_size) == 0)
6964 {
6965 if (is_elf64)
6966 {
6967 Elf64_Dyn *const dyn = (Elf64_Dyn *) buf;
6968 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
6969 union
6970 {
6971 Elf64_Xword map;
6972 unsigned char buf[sizeof (Elf64_Xword)];
6973 }
6974 rld_map;
6975 #endif
6976 #ifdef DT_MIPS_RLD_MAP
6977 if (dyn->d_tag == DT_MIPS_RLD_MAP)
6978 {
6979 if (linux_read_memory (dyn->d_un.d_val,
6980 rld_map.buf, sizeof (rld_map.buf)) == 0)
6981 return rld_map.map;
6982 else
6983 break;
6984 }
6985 #endif /* DT_MIPS_RLD_MAP */
6986 #ifdef DT_MIPS_RLD_MAP_REL
6987 if (dyn->d_tag == DT_MIPS_RLD_MAP_REL)
6988 {
6989 if (linux_read_memory (dyn->d_un.d_val + dynamic_memaddr,
6990 rld_map.buf, sizeof (rld_map.buf)) == 0)
6991 return rld_map.map;
6992 else
6993 break;
6994 }
6995 #endif /* DT_MIPS_RLD_MAP_REL */
6996
6997 if (dyn->d_tag == DT_DEBUG && map == -1)
6998 map = dyn->d_un.d_val;
6999
7000 if (dyn->d_tag == DT_NULL)
7001 break;
7002 }
7003 else
7004 {
7005 Elf32_Dyn *const dyn = (Elf32_Dyn *) buf;
7006 #if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
7007 union
7008 {
7009 Elf32_Word map;
7010 unsigned char buf[sizeof (Elf32_Word)];
7011 }
7012 rld_map;
7013 #endif
7014 #ifdef DT_MIPS_RLD_MAP
7015 if (dyn->d_tag == DT_MIPS_RLD_MAP)
7016 {
7017 if (linux_read_memory (dyn->d_un.d_val,
7018 rld_map.buf, sizeof (rld_map.buf)) == 0)
7019 return rld_map.map;
7020 else
7021 break;
7022 }
7023 #endif /* DT_MIPS_RLD_MAP */
7024 #ifdef DT_MIPS_RLD_MAP_REL
7025 if (dyn->d_tag == DT_MIPS_RLD_MAP_REL)
7026 {
7027 if (linux_read_memory (dyn->d_un.d_val + dynamic_memaddr,
7028 rld_map.buf, sizeof (rld_map.buf)) == 0)
7029 return rld_map.map;
7030 else
7031 break;
7032 }
7033 #endif /* DT_MIPS_RLD_MAP_REL */
7034
7035 if (dyn->d_tag == DT_DEBUG && map == -1)
7036 map = dyn->d_un.d_val;
7037
7038 if (dyn->d_tag == DT_NULL)
7039 break;
7040 }
7041
7042 dynamic_memaddr += dyn_size;
7043 }
7044
7045 return map;
7046 }
7047
7048 /* Read one pointer from MEMADDR in the inferior. */
7049
7050 static int
7051 read_one_ptr (CORE_ADDR memaddr, CORE_ADDR *ptr, int ptr_size)
7052 {
7053 int ret;
7054
7055 /* Go through a union so this works on either big or little endian
7056 hosts, when the inferior's pointer size is smaller than the size
7057 of CORE_ADDR. It is assumed the inferior's endianness is the
7058 same of the superior's. */
7059 union
7060 {
7061 CORE_ADDR core_addr;
7062 unsigned int ui;
7063 unsigned char uc;
7064 } addr;
7065
7066 ret = linux_read_memory (memaddr, &addr.uc, ptr_size);
7067 if (ret == 0)
7068 {
7069 if (ptr_size == sizeof (CORE_ADDR))
7070 *ptr = addr.core_addr;
7071 else if (ptr_size == sizeof (unsigned int))
7072 *ptr = addr.ui;
7073 else
7074 gdb_assert_not_reached ("unhandled pointer size");
7075 }
7076 return ret;
7077 }
7078
7079 struct link_map_offsets
7080 {
7081 /* Offset and size of r_debug.r_version. */
7082 int r_version_offset;
7083
7084 /* Offset and size of r_debug.r_map. */
7085 int r_map_offset;
7086
7087 /* Offset to l_addr field in struct link_map. */
7088 int l_addr_offset;
7089
7090 /* Offset to l_name field in struct link_map. */
7091 int l_name_offset;
7092
7093 /* Offset to l_ld field in struct link_map. */
7094 int l_ld_offset;
7095
7096 /* Offset to l_next field in struct link_map. */
7097 int l_next_offset;
7098
7099 /* Offset to l_prev field in struct link_map. */
7100 int l_prev_offset;
7101 };
7102
7103 /* Construct qXfer:libraries-svr4:read reply. */
7104
7105 static int
7106 linux_qxfer_libraries_svr4 (const char *annex, unsigned char *readbuf,
7107 unsigned const char *writebuf,
7108 CORE_ADDR offset, int len)
7109 {
7110 char *document;
7111 unsigned document_len;
7112 struct process_info_private *const priv = current_process ()->priv;
7113 char filename[PATH_MAX];
7114 int pid, is_elf64;
7115
7116 static const struct link_map_offsets lmo_32bit_offsets =
7117 {
7118 0, /* r_version offset. */
7119 4, /* r_debug.r_map offset. */
7120 0, /* l_addr offset in link_map. */
7121 4, /* l_name offset in link_map. */
7122 8, /* l_ld offset in link_map. */
7123 12, /* l_next offset in link_map. */
7124 16 /* l_prev offset in link_map. */
7125 };
7126
7127 static const struct link_map_offsets lmo_64bit_offsets =
7128 {
7129 0, /* r_version offset. */
7130 8, /* r_debug.r_map offset. */
7131 0, /* l_addr offset in link_map. */
7132 8, /* l_name offset in link_map. */
7133 16, /* l_ld offset in link_map. */
7134 24, /* l_next offset in link_map. */
7135 32 /* l_prev offset in link_map. */
7136 };
7137 const struct link_map_offsets *lmo;
7138 unsigned int machine;
7139 int ptr_size;
7140 CORE_ADDR lm_addr = 0, lm_prev = 0;
7141 int allocated = 1024;
7142 char *p;
7143 CORE_ADDR l_name, l_addr, l_ld, l_next, l_prev;
7144 int header_done = 0;
7145
7146 if (writebuf != NULL)
7147 return -2;
7148 if (readbuf == NULL)
7149 return -1;
7150
7151 pid = lwpid_of (current_thread);
7152 xsnprintf (filename, sizeof filename, "/proc/%d/exe", pid);
7153 is_elf64 = elf_64_file_p (filename, &machine);
7154 lmo = is_elf64 ? &lmo_64bit_offsets : &lmo_32bit_offsets;
7155 ptr_size = is_elf64 ? 8 : 4;
7156
7157 while (annex[0] != '\0')
7158 {
7159 const char *sep;
7160 CORE_ADDR *addrp;
7161 int len;
7162
7163 sep = strchr (annex, '=');
7164 if (sep == NULL)
7165 break;
7166
7167 len = sep - annex;
7168 if (len == 5 && startswith (annex, "start"))
7169 addrp = &lm_addr;
7170 else if (len == 4 && startswith (annex, "prev"))
7171 addrp = &lm_prev;
7172 else
7173 {
7174 annex = strchr (sep, ';');
7175 if (annex == NULL)
7176 break;
7177 annex++;
7178 continue;
7179 }
7180
7181 annex = decode_address_to_semicolon (addrp, sep + 1);
7182 }
7183
7184 if (lm_addr == 0)
7185 {
7186 int r_version = 0;
7187
7188 if (priv->r_debug == 0)
7189 priv->r_debug = get_r_debug (pid, is_elf64);
7190
7191 /* We failed to find DT_DEBUG. Such situation will not change
7192 for this inferior - do not retry it. Report it to GDB as
7193 E01, see for the reasons at the GDB solib-svr4.c side. */
7194 if (priv->r_debug == (CORE_ADDR) -1)
7195 return -1;
7196
7197 if (priv->r_debug != 0)
7198 {
7199 if (linux_read_memory (priv->r_debug + lmo->r_version_offset,
7200 (unsigned char *) &r_version,
7201 sizeof (r_version)) != 0
7202 || r_version != 1)
7203 {
7204 warning ("unexpected r_debug version %d", r_version);
7205 }
7206 else if (read_one_ptr (priv->r_debug + lmo->r_map_offset,
7207 &lm_addr, ptr_size) != 0)
7208 {
7209 warning ("unable to read r_map from 0x%lx",
7210 (long) priv->r_debug + lmo->r_map_offset);
7211 }
7212 }
7213 }
7214
7215 document = (char *) xmalloc (allocated);
7216 strcpy (document, "<library-list-svr4 version=\"1.0\"");
7217 p = document + strlen (document);
7218
7219 while (lm_addr
7220 && read_one_ptr (lm_addr + lmo->l_name_offset,
7221 &l_name, ptr_size) == 0
7222 && read_one_ptr (lm_addr + lmo->l_addr_offset,
7223 &l_addr, ptr_size) == 0
7224 && read_one_ptr (lm_addr + lmo->l_ld_offset,
7225 &l_ld, ptr_size) == 0
7226 && read_one_ptr (lm_addr + lmo->l_prev_offset,
7227 &l_prev, ptr_size) == 0
7228 && read_one_ptr (lm_addr + lmo->l_next_offset,
7229 &l_next, ptr_size) == 0)
7230 {
7231 unsigned char libname[PATH_MAX];
7232
7233 if (lm_prev != l_prev)
7234 {
7235 warning ("Corrupted shared library list: 0x%lx != 0x%lx",
7236 (long) lm_prev, (long) l_prev);
7237 break;
7238 }
7239
7240 /* Ignore the first entry even if it has valid name as the first entry
7241 corresponds to the main executable. The first entry should not be
7242 skipped if the dynamic loader was loaded late by a static executable
7243 (see solib-svr4.c parameter ignore_first). But in such case the main
7244 executable does not have PT_DYNAMIC present and this function already
7245 exited above due to failed get_r_debug. */
7246 if (lm_prev == 0)
7247 {
7248 sprintf (p, " main-lm=\"0x%lx\"", (unsigned long) lm_addr);
7249 p = p + strlen (p);
7250 }
7251 else
7252 {
7253 /* Not checking for error because reading may stop before
7254 we've got PATH_MAX worth of characters. */
7255 libname[0] = '\0';
7256 linux_read_memory (l_name, libname, sizeof (libname) - 1);
7257 libname[sizeof (libname) - 1] = '\0';
7258 if (libname[0] != '\0')
7259 {
7260 /* 6x the size for xml_escape_text below. */
7261 size_t len = 6 * strlen ((char *) libname);
7262
7263 if (!header_done)
7264 {
7265 /* Terminate `<library-list-svr4'. */
7266 *p++ = '>';
7267 header_done = 1;
7268 }
7269
7270 while (allocated < p - document + len + 200)
7271 {
7272 /* Expand to guarantee sufficient storage. */
7273 uintptr_t document_len = p - document;
7274
7275 document = (char *) xrealloc (document, 2 * allocated);
7276 allocated *= 2;
7277 p = document + document_len;
7278 }
7279
7280 std::string name = xml_escape_text ((char *) libname);
7281 p += sprintf (p, "<library name=\"%s\" lm=\"0x%lx\" "
7282 "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
7283 name.c_str (), (unsigned long) lm_addr,
7284 (unsigned long) l_addr, (unsigned long) l_ld);
7285 }
7286 }
7287
7288 lm_prev = lm_addr;
7289 lm_addr = l_next;
7290 }
7291
7292 if (!header_done)
7293 {
7294 /* Empty list; terminate `<library-list-svr4'. */
7295 strcpy (p, "/>");
7296 }
7297 else
7298 strcpy (p, "</library-list-svr4>");
7299
7300 document_len = strlen (document);
7301 if (offset < document_len)
7302 document_len -= offset;
7303 else
7304 document_len = 0;
7305 if (len > document_len)
7306 len = document_len;
7307
7308 memcpy (readbuf, document + offset, len);
7309 xfree (document);
7310
7311 return len;
7312 }
7313
7314 #ifdef HAVE_LINUX_BTRACE
7315
7316 /* See to_disable_btrace target method. */
7317
7318 static int
7319 linux_low_disable_btrace (struct btrace_target_info *tinfo)
7320 {
7321 enum btrace_error err;
7322
7323 err = linux_disable_btrace (tinfo);
7324 return (err == BTRACE_ERR_NONE ? 0 : -1);
7325 }
7326
7327 /* Encode an Intel Processor Trace configuration. */
7328
7329 static void
7330 linux_low_encode_pt_config (struct buffer *buffer,
7331 const struct btrace_data_pt_config *config)
7332 {
7333 buffer_grow_str (buffer, "<pt-config>\n");
7334
7335 switch (config->cpu.vendor)
7336 {
7337 case CV_INTEL:
7338 buffer_xml_printf (buffer, "<cpu vendor=\"GenuineIntel\" family=\"%u\" "
7339 "model=\"%u\" stepping=\"%u\"/>\n",
7340 config->cpu.family, config->cpu.model,
7341 config->cpu.stepping);
7342 break;
7343
7344 default:
7345 break;
7346 }
7347
7348 buffer_grow_str (buffer, "</pt-config>\n");
7349 }
7350
7351 /* Encode a raw buffer. */
7352
7353 static void
7354 linux_low_encode_raw (struct buffer *buffer, const gdb_byte *data,
7355 unsigned int size)
7356 {
7357 if (size == 0)
7358 return;
7359
7360 /* We use hex encoding - see common/rsp-low.h. */
7361 buffer_grow_str (buffer, "<raw>\n");
7362
7363 while (size-- > 0)
7364 {
7365 char elem[2];
7366
7367 elem[0] = tohex ((*data >> 4) & 0xf);
7368 elem[1] = tohex (*data++ & 0xf);
7369
7370 buffer_grow (buffer, elem, 2);
7371 }
7372
7373 buffer_grow_str (buffer, "</raw>\n");
7374 }
7375
7376 /* See to_read_btrace target method. */
7377
7378 static int
7379 linux_low_read_btrace (struct btrace_target_info *tinfo, struct buffer *buffer,
7380 enum btrace_read_type type)
7381 {
7382 struct btrace_data btrace;
7383 struct btrace_block *block;
7384 enum btrace_error err;
7385 int i;
7386
7387 btrace_data_init (&btrace);
7388
7389 err = linux_read_btrace (&btrace, tinfo, type);
7390 if (err != BTRACE_ERR_NONE)
7391 {
7392 if (err == BTRACE_ERR_OVERFLOW)
7393 buffer_grow_str0 (buffer, "E.Overflow.");
7394 else
7395 buffer_grow_str0 (buffer, "E.Generic Error.");
7396
7397 goto err;
7398 }
7399
7400 switch (btrace.format)
7401 {
7402 case BTRACE_FORMAT_NONE:
7403 buffer_grow_str0 (buffer, "E.No Trace.");
7404 goto err;
7405
7406 case BTRACE_FORMAT_BTS:
7407 buffer_grow_str (buffer, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
7408 buffer_grow_str (buffer, "<btrace version=\"1.0\">\n");
7409
7410 for (i = 0;
7411 VEC_iterate (btrace_block_s, btrace.variant.bts.blocks, i, block);
7412 i++)
7413 buffer_xml_printf (buffer, "<block begin=\"0x%s\" end=\"0x%s\"/>\n",
7414 paddress (block->begin), paddress (block->end));
7415
7416 buffer_grow_str0 (buffer, "</btrace>\n");
7417 break;
7418
7419 case BTRACE_FORMAT_PT:
7420 buffer_grow_str (buffer, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
7421 buffer_grow_str (buffer, "<btrace version=\"1.0\">\n");
7422 buffer_grow_str (buffer, "<pt>\n");
7423
7424 linux_low_encode_pt_config (buffer, &btrace.variant.pt.config);
7425
7426 linux_low_encode_raw (buffer, btrace.variant.pt.data,
7427 btrace.variant.pt.size);
7428
7429 buffer_grow_str (buffer, "</pt>\n");
7430 buffer_grow_str0 (buffer, "</btrace>\n");
7431 break;
7432
7433 default:
7434 buffer_grow_str0 (buffer, "E.Unsupported Trace Format.");
7435 goto err;
7436 }
7437
7438 btrace_data_fini (&btrace);
7439 return 0;
7440
7441 err:
7442 btrace_data_fini (&btrace);
7443 return -1;
7444 }
7445
7446 /* See to_btrace_conf target method. */
7447
7448 static int
7449 linux_low_btrace_conf (const struct btrace_target_info *tinfo,
7450 struct buffer *buffer)
7451 {
7452 const struct btrace_config *conf;
7453
7454 buffer_grow_str (buffer, "<!DOCTYPE btrace-conf SYSTEM \"btrace-conf.dtd\">\n");
7455 buffer_grow_str (buffer, "<btrace-conf version=\"1.0\">\n");
7456
7457 conf = linux_btrace_conf (tinfo);
7458 if (conf != NULL)
7459 {
7460 switch (conf->format)
7461 {
7462 case BTRACE_FORMAT_NONE:
7463 break;
7464
7465 case BTRACE_FORMAT_BTS:
7466 buffer_xml_printf (buffer, "<bts");
7467 buffer_xml_printf (buffer, " size=\"0x%x\"", conf->bts.size);
7468 buffer_xml_printf (buffer, " />\n");
7469 break;
7470
7471 case BTRACE_FORMAT_PT:
7472 buffer_xml_printf (buffer, "<pt");
7473 buffer_xml_printf (buffer, " size=\"0x%x\"", conf->pt.size);
7474 buffer_xml_printf (buffer, "/>\n");
7475 break;
7476 }
7477 }
7478
7479 buffer_grow_str0 (buffer, "</btrace-conf>\n");
7480 return 0;
7481 }
7482 #endif /* HAVE_LINUX_BTRACE */
7483
7484 /* See nat/linux-nat.h. */
7485
7486 ptid_t
7487 current_lwp_ptid (void)
7488 {
7489 return ptid_of (current_thread);
7490 }
7491
7492 /* Implementation of the target_ops method "breakpoint_kind_from_pc". */
7493
7494 static int
7495 linux_breakpoint_kind_from_pc (CORE_ADDR *pcptr)
7496 {
7497 if (the_low_target.breakpoint_kind_from_pc != NULL)
7498 return (*the_low_target.breakpoint_kind_from_pc) (pcptr);
7499 else
7500 return default_breakpoint_kind_from_pc (pcptr);
7501 }
7502
7503 /* Implementation of the target_ops method "sw_breakpoint_from_kind". */
7504
7505 static const gdb_byte *
7506 linux_sw_breakpoint_from_kind (int kind, int *size)
7507 {
7508 gdb_assert (the_low_target.sw_breakpoint_from_kind != NULL);
7509
7510 return (*the_low_target.sw_breakpoint_from_kind) (kind, size);
7511 }
7512
7513 /* Implementation of the target_ops method
7514 "breakpoint_kind_from_current_state". */
7515
7516 static int
7517 linux_breakpoint_kind_from_current_state (CORE_ADDR *pcptr)
7518 {
7519 if (the_low_target.breakpoint_kind_from_current_state != NULL)
7520 return (*the_low_target.breakpoint_kind_from_current_state) (pcptr);
7521 else
7522 return linux_breakpoint_kind_from_pc (pcptr);
7523 }
7524
7525 /* Default implementation of linux_target_ops method "set_pc" for
7526 32-bit pc register which is literally named "pc". */
7527
7528 void
7529 linux_set_pc_32bit (struct regcache *regcache, CORE_ADDR pc)
7530 {
7531 uint32_t newpc = pc;
7532
7533 supply_register_by_name (regcache, "pc", &newpc);
7534 }
7535
7536 /* Default implementation of linux_target_ops method "get_pc" for
7537 32-bit pc register which is literally named "pc". */
7538
7539 CORE_ADDR
7540 linux_get_pc_32bit (struct regcache *regcache)
7541 {
7542 uint32_t pc;
7543
7544 collect_register_by_name (regcache, "pc", &pc);
7545 if (debug_threads)
7546 debug_printf ("stop pc is 0x%" PRIx32 "\n", pc);
7547 return pc;
7548 }
7549
7550 /* Default implementation of linux_target_ops method "set_pc" for
7551 64-bit pc register which is literally named "pc". */
7552
7553 void
7554 linux_set_pc_64bit (struct regcache *regcache, CORE_ADDR pc)
7555 {
7556 uint64_t newpc = pc;
7557
7558 supply_register_by_name (regcache, "pc", &newpc);
7559 }
7560
7561 /* Default implementation of linux_target_ops method "get_pc" for
7562 64-bit pc register which is literally named "pc". */
7563
7564 CORE_ADDR
7565 linux_get_pc_64bit (struct regcache *regcache)
7566 {
7567 uint64_t pc;
7568
7569 collect_register_by_name (regcache, "pc", &pc);
7570 if (debug_threads)
7571 debug_printf ("stop pc is 0x%" PRIx64 "\n", pc);
7572 return pc;
7573 }
7574
7575
7576 static struct target_ops linux_target_ops = {
7577 linux_create_inferior,
7578 linux_post_create_inferior,
7579 linux_attach,
7580 linux_kill,
7581 linux_detach,
7582 linux_mourn,
7583 linux_join,
7584 linux_thread_alive,
7585 linux_resume,
7586 linux_wait,
7587 linux_fetch_registers,
7588 linux_store_registers,
7589 linux_prepare_to_access_memory,
7590 linux_done_accessing_memory,
7591 linux_read_memory,
7592 linux_write_memory,
7593 linux_look_up_symbols,
7594 linux_request_interrupt,
7595 linux_read_auxv,
7596 linux_supports_z_point_type,
7597 linux_insert_point,
7598 linux_remove_point,
7599 linux_stopped_by_sw_breakpoint,
7600 linux_supports_stopped_by_sw_breakpoint,
7601 linux_stopped_by_hw_breakpoint,
7602 linux_supports_stopped_by_hw_breakpoint,
7603 linux_supports_hardware_single_step,
7604 linux_stopped_by_watchpoint,
7605 linux_stopped_data_address,
7606 #if defined(__UCLIBC__) && defined(HAS_NOMMU) \
7607 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
7608 && defined(PT_TEXT_END_ADDR)
7609 linux_read_offsets,
7610 #else
7611 NULL,
7612 #endif
7613 #ifdef USE_THREAD_DB
7614 thread_db_get_tls_address,
7615 #else
7616 NULL,
7617 #endif
7618 linux_qxfer_spu,
7619 hostio_last_error_from_errno,
7620 linux_qxfer_osdata,
7621 linux_xfer_siginfo,
7622 linux_supports_non_stop,
7623 linux_async,
7624 linux_start_non_stop,
7625 linux_supports_multi_process,
7626 linux_supports_fork_events,
7627 linux_supports_vfork_events,
7628 linux_supports_exec_events,
7629 linux_handle_new_gdb_connection,
7630 #ifdef USE_THREAD_DB
7631 thread_db_handle_monitor_command,
7632 #else
7633 NULL,
7634 #endif
7635 linux_common_core_of_thread,
7636 linux_read_loadmap,
7637 linux_process_qsupported,
7638 linux_supports_tracepoints,
7639 linux_read_pc,
7640 linux_write_pc,
7641 linux_thread_stopped,
7642 NULL,
7643 linux_pause_all,
7644 linux_unpause_all,
7645 linux_stabilize_threads,
7646 linux_install_fast_tracepoint_jump_pad,
7647 linux_emit_ops,
7648 linux_supports_disable_randomization,
7649 linux_get_min_fast_tracepoint_insn_len,
7650 linux_qxfer_libraries_svr4,
7651 linux_supports_agent,
7652 #ifdef HAVE_LINUX_BTRACE
7653 linux_supports_btrace,
7654 linux_enable_btrace,
7655 linux_low_disable_btrace,
7656 linux_low_read_btrace,
7657 linux_low_btrace_conf,
7658 #else
7659 NULL,
7660 NULL,
7661 NULL,
7662 NULL,
7663 NULL,
7664 #endif
7665 linux_supports_range_stepping,
7666 linux_proc_pid_to_exec_file,
7667 linux_mntns_open_cloexec,
7668 linux_mntns_unlink,
7669 linux_mntns_readlink,
7670 linux_breakpoint_kind_from_pc,
7671 linux_sw_breakpoint_from_kind,
7672 linux_proc_tid_get_name,
7673 linux_breakpoint_kind_from_current_state,
7674 linux_supports_software_single_step,
7675 linux_supports_catch_syscall,
7676 linux_get_ipa_tdesc_idx,
7677 #if USE_THREAD_DB
7678 thread_db_thread_handle,
7679 #else
7680 NULL,
7681 #endif
7682 };
7683
7684 #ifdef HAVE_LINUX_REGSETS
7685 void
7686 initialize_regsets_info (struct regsets_info *info)
7687 {
7688 for (info->num_regsets = 0;
7689 info->regsets[info->num_regsets].size >= 0;
7690 info->num_regsets++)
7691 ;
7692 }
7693 #endif
7694
7695 void
7696 initialize_low (void)
7697 {
7698 struct sigaction sigchld_action;
7699
7700 memset (&sigchld_action, 0, sizeof (sigchld_action));
7701 set_target_ops (&linux_target_ops);
7702
7703 linux_ptrace_init_warnings ();
7704
7705 sigchld_action.sa_handler = sigchld_handler;
7706 sigemptyset (&sigchld_action.sa_mask);
7707 sigchld_action.sa_flags = SA_RESTART;
7708 sigaction (SIGCHLD, &sigchld_action, NULL);
7709
7710 initialize_low_arch ();
7711
7712 linux_check_ptrace_features ();
7713 }
This page took 0.338912 seconds and 5 git commands to generate.