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da6d8c04 1/* Low level interface to ptrace, for the remote server for GDB.
618f726f 2 Copyright (C) 1995-2016 Free Software Foundation, Inc.
da6d8c04
DJ
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
a9762ec7 8 the Free Software Foundation; either version 3 of the License, or
da6d8c04
DJ
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
a9762ec7 17 along with this program. If not, see <http://www.gnu.org/licenses/>. */
da6d8c04
DJ
18
19#include "server.h"
58caa3dc 20#include "linux-low.h"
125f8a3d 21#include "nat/linux-osdata.h"
58b4daa5 22#include "agent.h"
de0d863e 23#include "tdesc.h"
b20a6524 24#include "rsp-low.h"
f348d89a 25#include "signals-state-save-restore.h"
96d7229d
LM
26#include "nat/linux-nat.h"
27#include "nat/linux-waitpid.h"
8bdce1ff 28#include "gdb_wait.h"
5826e159 29#include "nat/gdb_ptrace.h"
125f8a3d
GB
30#include "nat/linux-ptrace.h"
31#include "nat/linux-procfs.h"
8cc73a39 32#include "nat/linux-personality.h"
da6d8c04
DJ
33#include <signal.h>
34#include <sys/ioctl.h>
35#include <fcntl.h>
0a30fbc4 36#include <unistd.h>
fd500816 37#include <sys/syscall.h>
f9387fc3 38#include <sched.h>
07e059b5
VP
39#include <ctype.h>
40#include <pwd.h>
41#include <sys/types.h>
42#include <dirent.h>
53ce3c39 43#include <sys/stat.h>
efcbbd14 44#include <sys/vfs.h>
1570b33e 45#include <sys/uio.h>
602e3198 46#include "filestuff.h"
c144c7a0 47#include "tracepoint.h"
533b0600 48#include "hostio.h"
276d4552 49#include <inttypes.h>
957f3f49
DE
50#ifndef ELFMAG0
51/* Don't include <linux/elf.h> here. If it got included by gdb_proc_service.h
52 then ELFMAG0 will have been defined. If it didn't get included by
53 gdb_proc_service.h then including it will likely introduce a duplicate
54 definition of elf_fpregset_t. */
55#include <elf.h>
56#endif
14d2069a 57#include "nat/linux-namespaces.h"
efcbbd14
UW
58
59#ifndef SPUFS_MAGIC
60#define SPUFS_MAGIC 0x23c9b64e
61#endif
da6d8c04 62
03583c20
UW
63#ifdef HAVE_PERSONALITY
64# include <sys/personality.h>
65# if !HAVE_DECL_ADDR_NO_RANDOMIZE
66# define ADDR_NO_RANDOMIZE 0x0040000
67# endif
68#endif
69
fd462a61
DJ
70#ifndef O_LARGEFILE
71#define O_LARGEFILE 0
72#endif
1a981360 73
db0dfaa0
LM
74/* Some targets did not define these ptrace constants from the start,
75 so gdbserver defines them locally here. In the future, these may
76 be removed after they are added to asm/ptrace.h. */
77#if !(defined(PT_TEXT_ADDR) \
78 || defined(PT_DATA_ADDR) \
79 || defined(PT_TEXT_END_ADDR))
80#if defined(__mcoldfire__)
81/* These are still undefined in 3.10 kernels. */
82#define PT_TEXT_ADDR 49*4
83#define PT_DATA_ADDR 50*4
84#define PT_TEXT_END_ADDR 51*4
85/* BFIN already defines these since at least 2.6.32 kernels. */
86#elif defined(BFIN)
87#define PT_TEXT_ADDR 220
88#define PT_TEXT_END_ADDR 224
89#define PT_DATA_ADDR 228
90/* These are still undefined in 3.10 kernels. */
91#elif defined(__TMS320C6X__)
92#define PT_TEXT_ADDR (0x10000*4)
93#define PT_DATA_ADDR (0x10004*4)
94#define PT_TEXT_END_ADDR (0x10008*4)
95#endif
96#endif
97
9accd112 98#ifdef HAVE_LINUX_BTRACE
125f8a3d 99# include "nat/linux-btrace.h"
734b0e4b 100# include "btrace-common.h"
9accd112
MM
101#endif
102
8365dcf5
TJB
103#ifndef HAVE_ELF32_AUXV_T
104/* Copied from glibc's elf.h. */
105typedef struct
106{
107 uint32_t a_type; /* Entry type */
108 union
109 {
110 uint32_t a_val; /* Integer value */
111 /* We use to have pointer elements added here. We cannot do that,
112 though, since it does not work when using 32-bit definitions
113 on 64-bit platforms and vice versa. */
114 } a_un;
115} Elf32_auxv_t;
116#endif
117
118#ifndef HAVE_ELF64_AUXV_T
119/* Copied from glibc's elf.h. */
120typedef struct
121{
122 uint64_t a_type; /* Entry type */
123 union
124 {
125 uint64_t a_val; /* Integer value */
126 /* We use to have pointer elements added here. We cannot do that,
127 though, since it does not work when using 32-bit definitions
128 on 64-bit platforms and vice versa. */
129 } a_un;
130} Elf64_auxv_t;
131#endif
132
ded48a5e
YQ
133/* Does the current host support PTRACE_GETREGSET? */
134int have_ptrace_getregset = -1;
135
cff068da
GB
136/* LWP accessors. */
137
138/* See nat/linux-nat.h. */
139
140ptid_t
141ptid_of_lwp (struct lwp_info *lwp)
142{
143 return ptid_of (get_lwp_thread (lwp));
144}
145
146/* See nat/linux-nat.h. */
147
4b134ca1
GB
148void
149lwp_set_arch_private_info (struct lwp_info *lwp,
150 struct arch_lwp_info *info)
151{
152 lwp->arch_private = info;
153}
154
155/* See nat/linux-nat.h. */
156
157struct arch_lwp_info *
158lwp_arch_private_info (struct lwp_info *lwp)
159{
160 return lwp->arch_private;
161}
162
163/* See nat/linux-nat.h. */
164
cff068da
GB
165int
166lwp_is_stopped (struct lwp_info *lwp)
167{
168 return lwp->stopped;
169}
170
171/* See nat/linux-nat.h. */
172
173enum target_stop_reason
174lwp_stop_reason (struct lwp_info *lwp)
175{
176 return lwp->stop_reason;
177}
178
05044653
PA
179/* A list of all unknown processes which receive stop signals. Some
180 other process will presumably claim each of these as forked
181 children momentarily. */
24a09b5f 182
05044653
PA
183struct simple_pid_list
184{
185 /* The process ID. */
186 int pid;
187
188 /* The status as reported by waitpid. */
189 int status;
190
191 /* Next in chain. */
192 struct simple_pid_list *next;
193};
194struct simple_pid_list *stopped_pids;
195
196/* Trivial list manipulation functions to keep track of a list of new
197 stopped processes. */
198
199static void
200add_to_pid_list (struct simple_pid_list **listp, int pid, int status)
201{
8d749320 202 struct simple_pid_list *new_pid = XNEW (struct simple_pid_list);
05044653
PA
203
204 new_pid->pid = pid;
205 new_pid->status = status;
206 new_pid->next = *listp;
207 *listp = new_pid;
208}
209
210static int
211pull_pid_from_list (struct simple_pid_list **listp, int pid, int *statusp)
212{
213 struct simple_pid_list **p;
214
215 for (p = listp; *p != NULL; p = &(*p)->next)
216 if ((*p)->pid == pid)
217 {
218 struct simple_pid_list *next = (*p)->next;
219
220 *statusp = (*p)->status;
221 xfree (*p);
222 *p = next;
223 return 1;
224 }
225 return 0;
226}
24a09b5f 227
bde24c0a
PA
228enum stopping_threads_kind
229 {
230 /* Not stopping threads presently. */
231 NOT_STOPPING_THREADS,
232
233 /* Stopping threads. */
234 STOPPING_THREADS,
235
236 /* Stopping and suspending threads. */
237 STOPPING_AND_SUSPENDING_THREADS
238 };
239
240/* This is set while stop_all_lwps is in effect. */
241enum stopping_threads_kind stopping_threads = NOT_STOPPING_THREADS;
0d62e5e8
DJ
242
243/* FIXME make into a target method? */
24a09b5f 244int using_threads = 1;
24a09b5f 245
fa593d66
PA
246/* True if we're presently stabilizing threads (moving them out of
247 jump pads). */
248static int stabilizing_threads;
249
2acc282a 250static void linux_resume_one_lwp (struct lwp_info *lwp,
54a0b537 251 int step, int signal, siginfo_t *info);
2bd7c093 252static void linux_resume (struct thread_resume *resume_info, size_t n);
7984d532
PA
253static void stop_all_lwps (int suspend, struct lwp_info *except);
254static void unstop_all_lwps (int unsuspend, struct lwp_info *except);
f50bf8e5 255static void unsuspend_all_lwps (struct lwp_info *except);
fa96cb38
PA
256static int linux_wait_for_event_filtered (ptid_t wait_ptid, ptid_t filter_ptid,
257 int *wstat, int options);
95954743 258static int linux_wait_for_event (ptid_t ptid, int *wstat, int options);
b3312d80 259static struct lwp_info *add_lwp (ptid_t ptid);
94585166 260static void linux_mourn (struct process_info *process);
c35fafde 261static int linux_stopped_by_watchpoint (void);
95954743 262static void mark_lwp_dead (struct lwp_info *lwp, int wstat);
00db26fa 263static int lwp_is_marked_dead (struct lwp_info *lwp);
d50171e4 264static void proceed_all_lwps (void);
d50171e4 265static int finish_step_over (struct lwp_info *lwp);
d50171e4 266static int kill_lwp (unsigned long lwpid, int signo);
863d01bd
PA
267static void enqueue_pending_signal (struct lwp_info *lwp, int signal, siginfo_t *info);
268static void complete_ongoing_step_over (void);
ece66d65 269static int linux_low_ptrace_options (int attached);
ced2dffb 270static int check_ptrace_stopped_lwp_gone (struct lwp_info *lp);
0e9a339e 271static int proceed_one_lwp (struct inferior_list_entry *entry, void *except);
d50171e4 272
582511be
PA
273/* When the event-loop is doing a step-over, this points at the thread
274 being stepped. */
275ptid_t step_over_bkpt;
276
7d00775e 277/* True if the low target can hardware single-step. */
d50171e4
PA
278
279static int
280can_hardware_single_step (void)
281{
7d00775e
AT
282 if (the_low_target.supports_hardware_single_step != NULL)
283 return the_low_target.supports_hardware_single_step ();
284 else
285 return 0;
286}
287
288/* True if the low target can software single-step. Such targets
fa5308bd 289 implement the GET_NEXT_PCS callback. */
7d00775e
AT
290
291static int
292can_software_single_step (void)
293{
fa5308bd 294 return (the_low_target.get_next_pcs != NULL);
d50171e4
PA
295}
296
297/* True if the low target supports memory breakpoints. If so, we'll
298 have a GET_PC implementation. */
299
300static int
301supports_breakpoints (void)
302{
303 return (the_low_target.get_pc != NULL);
304}
0d62e5e8 305
fa593d66
PA
306/* Returns true if this target can support fast tracepoints. This
307 does not mean that the in-process agent has been loaded in the
308 inferior. */
309
310static int
311supports_fast_tracepoints (void)
312{
313 return the_low_target.install_fast_tracepoint_jump_pad != NULL;
314}
315
c2d6af84
PA
316/* True if LWP is stopped in its stepping range. */
317
318static int
319lwp_in_step_range (struct lwp_info *lwp)
320{
321 CORE_ADDR pc = lwp->stop_pc;
322
323 return (pc >= lwp->step_range_start && pc < lwp->step_range_end);
324}
325
0d62e5e8
DJ
326struct pending_signals
327{
328 int signal;
32ca6d61 329 siginfo_t info;
0d62e5e8
DJ
330 struct pending_signals *prev;
331};
611cb4a5 332
bd99dc85
PA
333/* The read/write ends of the pipe registered as waitable file in the
334 event loop. */
335static int linux_event_pipe[2] = { -1, -1 };
336
337/* True if we're currently in async mode. */
338#define target_is_async_p() (linux_event_pipe[0] != -1)
339
02fc4de7 340static void send_sigstop (struct lwp_info *lwp);
fa96cb38 341static void wait_for_sigstop (void);
bd99dc85 342
d0722149
DE
343/* Return non-zero if HEADER is a 64-bit ELF file. */
344
345static int
214d508e 346elf_64_header_p (const Elf64_Ehdr *header, unsigned int *machine)
d0722149 347{
214d508e
L
348 if (header->e_ident[EI_MAG0] == ELFMAG0
349 && header->e_ident[EI_MAG1] == ELFMAG1
350 && header->e_ident[EI_MAG2] == ELFMAG2
351 && header->e_ident[EI_MAG3] == ELFMAG3)
352 {
353 *machine = header->e_machine;
354 return header->e_ident[EI_CLASS] == ELFCLASS64;
355
356 }
357 *machine = EM_NONE;
358 return -1;
d0722149
DE
359}
360
361/* Return non-zero if FILE is a 64-bit ELF file,
362 zero if the file is not a 64-bit ELF file,
363 and -1 if the file is not accessible or doesn't exist. */
364
be07f1a2 365static int
214d508e 366elf_64_file_p (const char *file, unsigned int *machine)
d0722149 367{
957f3f49 368 Elf64_Ehdr header;
d0722149
DE
369 int fd;
370
371 fd = open (file, O_RDONLY);
372 if (fd < 0)
373 return -1;
374
375 if (read (fd, &header, sizeof (header)) != sizeof (header))
376 {
377 close (fd);
378 return 0;
379 }
380 close (fd);
381
214d508e 382 return elf_64_header_p (&header, machine);
d0722149
DE
383}
384
be07f1a2
PA
385/* Accepts an integer PID; Returns true if the executable PID is
386 running is a 64-bit ELF file.. */
387
388int
214d508e 389linux_pid_exe_is_elf_64_file (int pid, unsigned int *machine)
be07f1a2 390{
d8d2a3ee 391 char file[PATH_MAX];
be07f1a2
PA
392
393 sprintf (file, "/proc/%d/exe", pid);
214d508e 394 return elf_64_file_p (file, machine);
be07f1a2
PA
395}
396
bd99dc85
PA
397static void
398delete_lwp (struct lwp_info *lwp)
399{
fa96cb38
PA
400 struct thread_info *thr = get_lwp_thread (lwp);
401
402 if (debug_threads)
403 debug_printf ("deleting %ld\n", lwpid_of (thr));
404
405 remove_thread (thr);
aa5ca48f 406 free (lwp->arch_private);
bd99dc85
PA
407 free (lwp);
408}
409
95954743
PA
410/* Add a process to the common process list, and set its private
411 data. */
412
413static struct process_info *
414linux_add_process (int pid, int attached)
415{
416 struct process_info *proc;
417
95954743 418 proc = add_process (pid, attached);
8d749320 419 proc->priv = XCNEW (struct process_info_private);
95954743 420
aa5ca48f 421 if (the_low_target.new_process != NULL)
fe978cb0 422 proc->priv->arch_private = the_low_target.new_process ();
aa5ca48f 423
95954743
PA
424 return proc;
425}
426
582511be
PA
427static CORE_ADDR get_pc (struct lwp_info *lwp);
428
ece66d65 429/* Call the target arch_setup function on the current thread. */
94585166
DB
430
431static void
432linux_arch_setup (void)
433{
434 the_low_target.arch_setup ();
435}
436
437/* Call the target arch_setup function on THREAD. */
438
439static void
440linux_arch_setup_thread (struct thread_info *thread)
441{
442 struct thread_info *saved_thread;
443
444 saved_thread = current_thread;
445 current_thread = thread;
446
447 linux_arch_setup ();
448
449 current_thread = saved_thread;
450}
451
452/* Handle a GNU/Linux extended wait response. If we see a clone,
453 fork, or vfork event, we need to add the new LWP to our list
454 (and return 0 so as not to report the trap to higher layers).
455 If we see an exec event, we will modify ORIG_EVENT_LWP to point
456 to a new LWP representing the new program. */
0d62e5e8 457
de0d863e 458static int
94585166 459handle_extended_wait (struct lwp_info **orig_event_lwp, int wstat)
24a09b5f 460{
94585166 461 struct lwp_info *event_lwp = *orig_event_lwp;
89a5711c 462 int event = linux_ptrace_get_extended_event (wstat);
de0d863e 463 struct thread_info *event_thr = get_lwp_thread (event_lwp);
54a0b537 464 struct lwp_info *new_lwp;
24a09b5f 465
65706a29
PA
466 gdb_assert (event_lwp->waitstatus.kind == TARGET_WAITKIND_IGNORE);
467
82075af2
JS
468 /* All extended events we currently use are mid-syscall. Only
469 PTRACE_EVENT_STOP is delivered more like a signal-stop, but
470 you have to be using PTRACE_SEIZE to get that. */
471 event_lwp->syscall_state = TARGET_WAITKIND_SYSCALL_ENTRY;
472
c269dbdb
DB
473 if ((event == PTRACE_EVENT_FORK) || (event == PTRACE_EVENT_VFORK)
474 || (event == PTRACE_EVENT_CLONE))
24a09b5f 475 {
95954743 476 ptid_t ptid;
24a09b5f 477 unsigned long new_pid;
05044653 478 int ret, status;
24a09b5f 479
de0d863e 480 /* Get the pid of the new lwp. */
d86d4aaf 481 ptrace (PTRACE_GETEVENTMSG, lwpid_of (event_thr), (PTRACE_TYPE_ARG3) 0,
56f7af9c 482 &new_pid);
24a09b5f
DJ
483
484 /* If we haven't already seen the new PID stop, wait for it now. */
05044653 485 if (!pull_pid_from_list (&stopped_pids, new_pid, &status))
24a09b5f
DJ
486 {
487 /* The new child has a pending SIGSTOP. We can't affect it until it
488 hits the SIGSTOP, but we're already attached. */
489
97438e3f 490 ret = my_waitpid (new_pid, &status, __WALL);
24a09b5f
DJ
491
492 if (ret == -1)
493 perror_with_name ("waiting for new child");
494 else if (ret != new_pid)
495 warning ("wait returned unexpected PID %d", ret);
da5898ce 496 else if (!WIFSTOPPED (status))
24a09b5f
DJ
497 warning ("wait returned unexpected status 0x%x", status);
498 }
499
c269dbdb 500 if (event == PTRACE_EVENT_FORK || event == PTRACE_EVENT_VFORK)
de0d863e
DB
501 {
502 struct process_info *parent_proc;
503 struct process_info *child_proc;
504 struct lwp_info *child_lwp;
bfacd19d 505 struct thread_info *child_thr;
de0d863e
DB
506 struct target_desc *tdesc;
507
508 ptid = ptid_build (new_pid, new_pid, 0);
509
510 if (debug_threads)
511 {
512 debug_printf ("HEW: Got fork event from LWP %ld, "
513 "new child is %d\n",
514 ptid_get_lwp (ptid_of (event_thr)),
515 ptid_get_pid (ptid));
516 }
517
518 /* Add the new process to the tables and clone the breakpoint
519 lists of the parent. We need to do this even if the new process
520 will be detached, since we will need the process object and the
521 breakpoints to remove any breakpoints from memory when we
522 detach, and the client side will access registers. */
523 child_proc = linux_add_process (new_pid, 0);
524 gdb_assert (child_proc != NULL);
525 child_lwp = add_lwp (ptid);
526 gdb_assert (child_lwp != NULL);
527 child_lwp->stopped = 1;
bfacd19d
DB
528 child_lwp->must_set_ptrace_flags = 1;
529 child_lwp->status_pending_p = 0;
530 child_thr = get_lwp_thread (child_lwp);
531 child_thr->last_resume_kind = resume_stop;
998d452a
PA
532 child_thr->last_status.kind = TARGET_WAITKIND_STOPPED;
533
863d01bd 534 /* If we're suspending all threads, leave this one suspended
0f8288ae
YQ
535 too. If the fork/clone parent is stepping over a breakpoint,
536 all other threads have been suspended already. Leave the
537 child suspended too. */
538 if (stopping_threads == STOPPING_AND_SUSPENDING_THREADS
539 || event_lwp->bp_reinsert != 0)
863d01bd
PA
540 {
541 if (debug_threads)
542 debug_printf ("HEW: leaving child suspended\n");
543 child_lwp->suspended = 1;
544 }
545
de0d863e
DB
546 parent_proc = get_thread_process (event_thr);
547 child_proc->attached = parent_proc->attached;
2e7b624b
YQ
548
549 if (event_lwp->bp_reinsert != 0
550 && can_software_single_step ()
551 && event == PTRACE_EVENT_VFORK)
552 {
2e7b624b
YQ
553 /* If we leave reinsert breakpoints there, child will
554 hit it, so uninsert reinsert breakpoints from parent
555 (and child). Once vfork child is done, reinsert
556 them back to parent. */
bec903c9 557 uninsert_reinsert_breakpoints (event_thr);
2e7b624b
YQ
558 }
559
63c40ec7 560 clone_all_breakpoints (child_thr, event_thr);
de0d863e 561
8d749320 562 tdesc = XNEW (struct target_desc);
de0d863e
DB
563 copy_target_description (tdesc, parent_proc->tdesc);
564 child_proc->tdesc = tdesc;
de0d863e 565
3a8a0396
DB
566 /* Clone arch-specific process data. */
567 if (the_low_target.new_fork != NULL)
568 the_low_target.new_fork (parent_proc, child_proc);
569
de0d863e 570 /* Save fork info in the parent thread. */
c269dbdb
DB
571 if (event == PTRACE_EVENT_FORK)
572 event_lwp->waitstatus.kind = TARGET_WAITKIND_FORKED;
573 else if (event == PTRACE_EVENT_VFORK)
574 event_lwp->waitstatus.kind = TARGET_WAITKIND_VFORKED;
575
de0d863e 576 event_lwp->waitstatus.value.related_pid = ptid;
c269dbdb 577
de0d863e
DB
578 /* The status_pending field contains bits denoting the
579 extended event, so when the pending event is handled,
580 the handler will look at lwp->waitstatus. */
581 event_lwp->status_pending_p = 1;
582 event_lwp->status_pending = wstat;
583
8a81c5d7 584 /* If the parent thread is doing step-over with reinsert
2e7b624b
YQ
585 breakpoints, the list of reinsert breakpoints are cloned
586 from the parent's. Remove them from the child process.
587 In case of vfork, we'll reinsert them back once vforked
588 child is done. */
8a81c5d7 589 if (event_lwp->bp_reinsert != 0
2e7b624b 590 && can_software_single_step ())
8a81c5d7 591 {
8a81c5d7
YQ
592 /* The child process is forked and stopped, so it is safe
593 to access its memory without stopping all other threads
594 from other processes. */
bec903c9 595 delete_reinsert_breakpoints (child_thr);
8a81c5d7 596
bec903c9
YQ
597 gdb_assert (has_reinsert_breakpoints (event_thr));
598 gdb_assert (!has_reinsert_breakpoints (child_thr));
8a81c5d7
YQ
599 }
600
de0d863e
DB
601 /* Report the event. */
602 return 0;
603 }
604
fa96cb38
PA
605 if (debug_threads)
606 debug_printf ("HEW: Got clone event "
607 "from LWP %ld, new child is LWP %ld\n",
608 lwpid_of (event_thr), new_pid);
609
d86d4aaf 610 ptid = ptid_build (pid_of (event_thr), new_pid, 0);
b3312d80 611 new_lwp = add_lwp (ptid);
24a09b5f 612
e27d73f6
DE
613 /* Either we're going to immediately resume the new thread
614 or leave it stopped. linux_resume_one_lwp is a nop if it
615 thinks the thread is currently running, so set this first
616 before calling linux_resume_one_lwp. */
617 new_lwp->stopped = 1;
618
0f8288ae
YQ
619 /* If we're suspending all threads, leave this one suspended
620 too. If the fork/clone parent is stepping over a breakpoint,
621 all other threads have been suspended already. Leave the
622 child suspended too. */
623 if (stopping_threads == STOPPING_AND_SUSPENDING_THREADS
624 || event_lwp->bp_reinsert != 0)
bde24c0a
PA
625 new_lwp->suspended = 1;
626
da5898ce
DJ
627 /* Normally we will get the pending SIGSTOP. But in some cases
628 we might get another signal delivered to the group first.
f21cc1a2 629 If we do get another signal, be sure not to lose it. */
20ba1ce6 630 if (WSTOPSIG (status) != SIGSTOP)
da5898ce 631 {
54a0b537 632 new_lwp->stop_expected = 1;
20ba1ce6
PA
633 new_lwp->status_pending_p = 1;
634 new_lwp->status_pending = status;
da5898ce 635 }
65706a29
PA
636 else if (report_thread_events)
637 {
638 new_lwp->waitstatus.kind = TARGET_WAITKIND_THREAD_CREATED;
639 new_lwp->status_pending_p = 1;
640 new_lwp->status_pending = status;
641 }
de0d863e
DB
642
643 /* Don't report the event. */
644 return 1;
24a09b5f 645 }
c269dbdb
DB
646 else if (event == PTRACE_EVENT_VFORK_DONE)
647 {
648 event_lwp->waitstatus.kind = TARGET_WAITKIND_VFORK_DONE;
649
2e7b624b
YQ
650 if (event_lwp->bp_reinsert != 0 && can_software_single_step ())
651 {
bec903c9 652 reinsert_reinsert_breakpoints (event_thr);
2e7b624b 653
bec903c9 654 gdb_assert (has_reinsert_breakpoints (event_thr));
2e7b624b
YQ
655 }
656
c269dbdb
DB
657 /* Report the event. */
658 return 0;
659 }
94585166
DB
660 else if (event == PTRACE_EVENT_EXEC && report_exec_events)
661 {
662 struct process_info *proc;
82075af2 663 VEC (int) *syscalls_to_catch;
94585166
DB
664 ptid_t event_ptid;
665 pid_t event_pid;
666
667 if (debug_threads)
668 {
669 debug_printf ("HEW: Got exec event from LWP %ld\n",
670 lwpid_of (event_thr));
671 }
672
673 /* Get the event ptid. */
674 event_ptid = ptid_of (event_thr);
675 event_pid = ptid_get_pid (event_ptid);
676
82075af2 677 /* Save the syscall list from the execing process. */
94585166 678 proc = get_thread_process (event_thr);
82075af2
JS
679 syscalls_to_catch = proc->syscalls_to_catch;
680 proc->syscalls_to_catch = NULL;
681
682 /* Delete the execing process and all its threads. */
94585166
DB
683 linux_mourn (proc);
684 current_thread = NULL;
685
686 /* Create a new process/lwp/thread. */
687 proc = linux_add_process (event_pid, 0);
688 event_lwp = add_lwp (event_ptid);
689 event_thr = get_lwp_thread (event_lwp);
690 gdb_assert (current_thread == event_thr);
691 linux_arch_setup_thread (event_thr);
692
693 /* Set the event status. */
694 event_lwp->waitstatus.kind = TARGET_WAITKIND_EXECD;
695 event_lwp->waitstatus.value.execd_pathname
696 = xstrdup (linux_proc_pid_to_exec_file (lwpid_of (event_thr)));
697
698 /* Mark the exec status as pending. */
699 event_lwp->stopped = 1;
700 event_lwp->status_pending_p = 1;
701 event_lwp->status_pending = wstat;
702 event_thr->last_resume_kind = resume_continue;
703 event_thr->last_status.kind = TARGET_WAITKIND_IGNORE;
704
82075af2
JS
705 /* Update syscall state in the new lwp, effectively mid-syscall too. */
706 event_lwp->syscall_state = TARGET_WAITKIND_SYSCALL_ENTRY;
707
708 /* Restore the list to catch. Don't rely on the client, which is free
709 to avoid sending a new list when the architecture doesn't change.
710 Also, for ANY_SYSCALL, the architecture doesn't really matter. */
711 proc->syscalls_to_catch = syscalls_to_catch;
712
94585166
DB
713 /* Report the event. */
714 *orig_event_lwp = event_lwp;
715 return 0;
716 }
de0d863e
DB
717
718 internal_error (__FILE__, __LINE__, _("unknown ptrace event %d"), event);
24a09b5f
DJ
719}
720
d50171e4
PA
721/* Return the PC as read from the regcache of LWP, without any
722 adjustment. */
723
724static CORE_ADDR
725get_pc (struct lwp_info *lwp)
726{
0bfdf32f 727 struct thread_info *saved_thread;
d50171e4
PA
728 struct regcache *regcache;
729 CORE_ADDR pc;
730
731 if (the_low_target.get_pc == NULL)
732 return 0;
733
0bfdf32f
GB
734 saved_thread = current_thread;
735 current_thread = get_lwp_thread (lwp);
d50171e4 736
0bfdf32f 737 regcache = get_thread_regcache (current_thread, 1);
d50171e4
PA
738 pc = (*the_low_target.get_pc) (regcache);
739
740 if (debug_threads)
87ce2a04 741 debug_printf ("pc is 0x%lx\n", (long) pc);
d50171e4 742
0bfdf32f 743 current_thread = saved_thread;
d50171e4
PA
744 return pc;
745}
746
82075af2 747/* This function should only be called if LWP got a SYSCALL_SIGTRAP.
4cc32bec 748 Fill *SYSNO with the syscall nr trapped. */
82075af2
JS
749
750static void
4cc32bec 751get_syscall_trapinfo (struct lwp_info *lwp, int *sysno)
82075af2
JS
752{
753 struct thread_info *saved_thread;
754 struct regcache *regcache;
755
756 if (the_low_target.get_syscall_trapinfo == NULL)
757 {
758 /* If we cannot get the syscall trapinfo, report an unknown
4cc32bec 759 system call number. */
82075af2 760 *sysno = UNKNOWN_SYSCALL;
82075af2
JS
761 return;
762 }
763
764 saved_thread = current_thread;
765 current_thread = get_lwp_thread (lwp);
766
767 regcache = get_thread_regcache (current_thread, 1);
4cc32bec 768 (*the_low_target.get_syscall_trapinfo) (regcache, sysno);
82075af2
JS
769
770 if (debug_threads)
4cc32bec 771 debug_printf ("get_syscall_trapinfo sysno %d\n", *sysno);
82075af2
JS
772
773 current_thread = saved_thread;
774}
775
e7ad2f14 776static int check_stopped_by_watchpoint (struct lwp_info *child);
0d62e5e8 777
e7ad2f14
PA
778/* Called when the LWP stopped for a signal/trap. If it stopped for a
779 trap check what caused it (breakpoint, watchpoint, trace, etc.),
780 and save the result in the LWP's stop_reason field. If it stopped
781 for a breakpoint, decrement the PC if necessary on the lwp's
782 architecture. Returns true if we now have the LWP's stop PC. */
0d62e5e8 783
582511be 784static int
e7ad2f14 785save_stop_reason (struct lwp_info *lwp)
0d62e5e8 786{
582511be
PA
787 CORE_ADDR pc;
788 CORE_ADDR sw_breakpoint_pc;
789 struct thread_info *saved_thread;
3e572f71
PA
790#if USE_SIGTRAP_SIGINFO
791 siginfo_t siginfo;
792#endif
d50171e4
PA
793
794 if (the_low_target.get_pc == NULL)
795 return 0;
0d62e5e8 796
582511be
PA
797 pc = get_pc (lwp);
798 sw_breakpoint_pc = pc - the_low_target.decr_pc_after_break;
d50171e4 799
582511be
PA
800 /* breakpoint_at reads from the current thread. */
801 saved_thread = current_thread;
802 current_thread = get_lwp_thread (lwp);
47c0c975 803
3e572f71
PA
804#if USE_SIGTRAP_SIGINFO
805 if (ptrace (PTRACE_GETSIGINFO, lwpid_of (current_thread),
806 (PTRACE_TYPE_ARG3) 0, &siginfo) == 0)
807 {
808 if (siginfo.si_signo == SIGTRAP)
809 {
e7ad2f14
PA
810 if (GDB_ARCH_IS_TRAP_BRKPT (siginfo.si_code)
811 && GDB_ARCH_IS_TRAP_HWBKPT (siginfo.si_code))
3e572f71 812 {
e7ad2f14
PA
813 /* The si_code is ambiguous on this arch -- check debug
814 registers. */
815 if (!check_stopped_by_watchpoint (lwp))
816 lwp->stop_reason = TARGET_STOPPED_BY_SW_BREAKPOINT;
817 }
818 else if (GDB_ARCH_IS_TRAP_BRKPT (siginfo.si_code))
819 {
820 /* If we determine the LWP stopped for a SW breakpoint,
821 trust it. Particularly don't check watchpoint
822 registers, because at least on s390, we'd find
823 stopped-by-watchpoint as long as there's a watchpoint
824 set. */
3e572f71 825 lwp->stop_reason = TARGET_STOPPED_BY_SW_BREAKPOINT;
3e572f71 826 }
e7ad2f14 827 else if (GDB_ARCH_IS_TRAP_HWBKPT (siginfo.si_code))
3e572f71 828 {
e7ad2f14
PA
829 /* This can indicate either a hardware breakpoint or
830 hardware watchpoint. Check debug registers. */
831 if (!check_stopped_by_watchpoint (lwp))
832 lwp->stop_reason = TARGET_STOPPED_BY_HW_BREAKPOINT;
3e572f71 833 }
2bf6fb9d
PA
834 else if (siginfo.si_code == TRAP_TRACE)
835 {
e7ad2f14
PA
836 /* We may have single stepped an instruction that
837 triggered a watchpoint. In that case, on some
838 architectures (such as x86), instead of TRAP_HWBKPT,
839 si_code indicates TRAP_TRACE, and we need to check
840 the debug registers separately. */
841 if (!check_stopped_by_watchpoint (lwp))
842 lwp->stop_reason = TARGET_STOPPED_BY_SINGLE_STEP;
2bf6fb9d 843 }
3e572f71
PA
844 }
845 }
846#else
582511be
PA
847 /* We may have just stepped a breakpoint instruction. E.g., in
848 non-stop mode, GDB first tells the thread A to step a range, and
849 then the user inserts a breakpoint inside the range. In that
8090aef2
PA
850 case we need to report the breakpoint PC. */
851 if ((!lwp->stepping || lwp->stop_pc == sw_breakpoint_pc)
582511be 852 && (*the_low_target.breakpoint_at) (sw_breakpoint_pc))
e7ad2f14
PA
853 lwp->stop_reason = TARGET_STOPPED_BY_SW_BREAKPOINT;
854
855 if (hardware_breakpoint_inserted_here (pc))
856 lwp->stop_reason = TARGET_STOPPED_BY_HW_BREAKPOINT;
857
858 if (lwp->stop_reason == TARGET_STOPPED_BY_NO_REASON)
859 check_stopped_by_watchpoint (lwp);
860#endif
861
862 if (lwp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT)
582511be
PA
863 {
864 if (debug_threads)
865 {
866 struct thread_info *thr = get_lwp_thread (lwp);
867
868 debug_printf ("CSBB: %s stopped by software breakpoint\n",
869 target_pid_to_str (ptid_of (thr)));
870 }
871
872 /* Back up the PC if necessary. */
873 if (pc != sw_breakpoint_pc)
e7ad2f14 874 {
582511be
PA
875 struct regcache *regcache
876 = get_thread_regcache (current_thread, 1);
877 (*the_low_target.set_pc) (regcache, sw_breakpoint_pc);
878 }
879
e7ad2f14
PA
880 /* Update this so we record the correct stop PC below. */
881 pc = sw_breakpoint_pc;
582511be 882 }
e7ad2f14 883 else if (lwp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT)
582511be
PA
884 {
885 if (debug_threads)
886 {
887 struct thread_info *thr = get_lwp_thread (lwp);
888
889 debug_printf ("CSBB: %s stopped by hardware breakpoint\n",
890 target_pid_to_str (ptid_of (thr)));
891 }
e7ad2f14
PA
892 }
893 else if (lwp->stop_reason == TARGET_STOPPED_BY_WATCHPOINT)
894 {
895 if (debug_threads)
896 {
897 struct thread_info *thr = get_lwp_thread (lwp);
47c0c975 898
e7ad2f14
PA
899 debug_printf ("CSBB: %s stopped by hardware watchpoint\n",
900 target_pid_to_str (ptid_of (thr)));
901 }
582511be 902 }
e7ad2f14
PA
903 else if (lwp->stop_reason == TARGET_STOPPED_BY_SINGLE_STEP)
904 {
905 if (debug_threads)
906 {
907 struct thread_info *thr = get_lwp_thread (lwp);
582511be 908
e7ad2f14
PA
909 debug_printf ("CSBB: %s stopped by trace\n",
910 target_pid_to_str (ptid_of (thr)));
911 }
912 }
913
914 lwp->stop_pc = pc;
582511be 915 current_thread = saved_thread;
e7ad2f14 916 return 1;
0d62e5e8 917}
ce3a066d 918
b3312d80 919static struct lwp_info *
95954743 920add_lwp (ptid_t ptid)
611cb4a5 921{
54a0b537 922 struct lwp_info *lwp;
0d62e5e8 923
8d749320 924 lwp = XCNEW (struct lwp_info);
00db26fa
PA
925
926 lwp->waitstatus.kind = TARGET_WAITKIND_IGNORE;
0d62e5e8 927
aa5ca48f 928 if (the_low_target.new_thread != NULL)
34c703da 929 the_low_target.new_thread (lwp);
aa5ca48f 930
f7667f0d 931 lwp->thread = add_thread (ptid, lwp);
0d62e5e8 932
54a0b537 933 return lwp;
0d62e5e8 934}
611cb4a5 935
da6d8c04
DJ
936/* Start an inferior process and returns its pid.
937 ALLARGS is a vector of program-name and args. */
938
ce3a066d
DJ
939static int
940linux_create_inferior (char *program, char **allargs)
da6d8c04 941{
a6dbe5df 942 struct lwp_info *new_lwp;
da6d8c04 943 int pid;
95954743 944 ptid_t ptid;
8cc73a39
SDJ
945 struct cleanup *restore_personality
946 = maybe_disable_address_space_randomization (disable_randomization);
03583c20 947
42c81e2a 948#if defined(__UCLIBC__) && defined(HAS_NOMMU)
52fb6437
NS
949 pid = vfork ();
950#else
da6d8c04 951 pid = fork ();
52fb6437 952#endif
da6d8c04
DJ
953 if (pid < 0)
954 perror_with_name ("fork");
955
956 if (pid == 0)
957 {
602e3198 958 close_most_fds ();
b8e1b30e 959 ptrace (PTRACE_TRACEME, 0, (PTRACE_TYPE_ARG3) 0, (PTRACE_TYPE_ARG4) 0);
da6d8c04 960
a9fa9f7d
DJ
961 setpgid (0, 0);
962
e0f9f062
DE
963 /* If gdbserver is connected to gdb via stdio, redirect the inferior's
964 stdout to stderr so that inferior i/o doesn't corrupt the connection.
965 Also, redirect stdin to /dev/null. */
966 if (remote_connection_is_stdio ())
967 {
968 close (0);
969 open ("/dev/null", O_RDONLY);
970 dup2 (2, 1);
3e52c33d
JK
971 if (write (2, "stdin/stdout redirected\n",
972 sizeof ("stdin/stdout redirected\n") - 1) < 0)
8c29b58e
YQ
973 {
974 /* Errors ignored. */;
975 }
e0f9f062
DE
976 }
977
f348d89a
PA
978 restore_original_signals_state ();
979
2b876972
DJ
980 execv (program, allargs);
981 if (errno == ENOENT)
982 execvp (program, allargs);
da6d8c04
DJ
983
984 fprintf (stderr, "Cannot exec %s: %s.\n", program,
d07c63e7 985 strerror (errno));
da6d8c04
DJ
986 fflush (stderr);
987 _exit (0177);
988 }
989
8cc73a39 990 do_cleanups (restore_personality);
03583c20 991
55d7b841 992 linux_add_process (pid, 0);
95954743
PA
993
994 ptid = ptid_build (pid, pid, 0);
995 new_lwp = add_lwp (ptid);
a6dbe5df 996 new_lwp->must_set_ptrace_flags = 1;
611cb4a5 997
a9fa9f7d 998 return pid;
da6d8c04
DJ
999}
1000
ece66d65
JS
1001/* Implement the post_create_inferior target_ops method. */
1002
1003static void
1004linux_post_create_inferior (void)
1005{
1006 struct lwp_info *lwp = get_thread_lwp (current_thread);
1007
1008 linux_arch_setup ();
1009
1010 if (lwp->must_set_ptrace_flags)
1011 {
1012 struct process_info *proc = current_process ();
1013 int options = linux_low_ptrace_options (proc->attached);
1014
1015 linux_enable_event_reporting (lwpid_of (current_thread), options);
1016 lwp->must_set_ptrace_flags = 0;
1017 }
1018}
1019
8784d563
PA
1020/* Attach to an inferior process. Returns 0 on success, ERRNO on
1021 error. */
da6d8c04 1022
7ae1a6a6
PA
1023int
1024linux_attach_lwp (ptid_t ptid)
da6d8c04 1025{
54a0b537 1026 struct lwp_info *new_lwp;
7ae1a6a6 1027 int lwpid = ptid_get_lwp (ptid);
611cb4a5 1028
b8e1b30e 1029 if (ptrace (PTRACE_ATTACH, lwpid, (PTRACE_TYPE_ARG3) 0, (PTRACE_TYPE_ARG4) 0)
56f7af9c 1030 != 0)
7ae1a6a6 1031 return errno;
24a09b5f 1032
b3312d80 1033 new_lwp = add_lwp (ptid);
0d62e5e8 1034
a6dbe5df
PA
1035 /* We need to wait for SIGSTOP before being able to make the next
1036 ptrace call on this LWP. */
1037 new_lwp->must_set_ptrace_flags = 1;
1038
644cebc9 1039 if (linux_proc_pid_is_stopped (lwpid))
c14d7ab2
PA
1040 {
1041 if (debug_threads)
87ce2a04 1042 debug_printf ("Attached to a stopped process\n");
c14d7ab2
PA
1043
1044 /* The process is definitely stopped. It is in a job control
1045 stop, unless the kernel predates the TASK_STOPPED /
1046 TASK_TRACED distinction, in which case it might be in a
1047 ptrace stop. Make sure it is in a ptrace stop; from there we
1048 can kill it, signal it, et cetera.
1049
1050 First make sure there is a pending SIGSTOP. Since we are
1051 already attached, the process can not transition from stopped
1052 to running without a PTRACE_CONT; so we know this signal will
1053 go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
1054 probably already in the queue (unless this kernel is old
1055 enough to use TASK_STOPPED for ptrace stops); but since
1056 SIGSTOP is not an RT signal, it can only be queued once. */
1057 kill_lwp (lwpid, SIGSTOP);
1058
1059 /* Finally, resume the stopped process. This will deliver the
1060 SIGSTOP (or a higher priority signal, just like normal
1061 PTRACE_ATTACH), which we'll catch later on. */
b8e1b30e 1062 ptrace (PTRACE_CONT, lwpid, (PTRACE_TYPE_ARG3) 0, (PTRACE_TYPE_ARG4) 0);
c14d7ab2
PA
1063 }
1064
0d62e5e8 1065 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
0e21c1ec
DE
1066 brings it to a halt.
1067
1068 There are several cases to consider here:
1069
1070 1) gdbserver has already attached to the process and is being notified
1b3f6016 1071 of a new thread that is being created.
d50171e4
PA
1072 In this case we should ignore that SIGSTOP and resume the
1073 process. This is handled below by setting stop_expected = 1,
8336d594 1074 and the fact that add_thread sets last_resume_kind ==
d50171e4 1075 resume_continue.
0e21c1ec
DE
1076
1077 2) This is the first thread (the process thread), and we're attaching
1b3f6016
PA
1078 to it via attach_inferior.
1079 In this case we want the process thread to stop.
d50171e4
PA
1080 This is handled by having linux_attach set last_resume_kind ==
1081 resume_stop after we return.
e3deef73
LM
1082
1083 If the pid we are attaching to is also the tgid, we attach to and
1084 stop all the existing threads. Otherwise, we attach to pid and
1085 ignore any other threads in the same group as this pid.
0e21c1ec
DE
1086
1087 3) GDB is connecting to gdbserver and is requesting an enumeration of all
1b3f6016
PA
1088 existing threads.
1089 In this case we want the thread to stop.
1090 FIXME: This case is currently not properly handled.
1091 We should wait for the SIGSTOP but don't. Things work apparently
1092 because enough time passes between when we ptrace (ATTACH) and when
1093 gdb makes the next ptrace call on the thread.
0d62e5e8
DJ
1094
1095 On the other hand, if we are currently trying to stop all threads, we
1096 should treat the new thread as if we had sent it a SIGSTOP. This works
54a0b537 1097 because we are guaranteed that the add_lwp call above added us to the
0e21c1ec
DE
1098 end of the list, and so the new thread has not yet reached
1099 wait_for_sigstop (but will). */
d50171e4 1100 new_lwp->stop_expected = 1;
0d62e5e8 1101
7ae1a6a6 1102 return 0;
95954743
PA
1103}
1104
8784d563
PA
1105/* Callback for linux_proc_attach_tgid_threads. Attach to PTID if not
1106 already attached. Returns true if a new LWP is found, false
1107 otherwise. */
1108
1109static int
1110attach_proc_task_lwp_callback (ptid_t ptid)
1111{
1112 /* Is this a new thread? */
1113 if (find_thread_ptid (ptid) == NULL)
1114 {
1115 int lwpid = ptid_get_lwp (ptid);
1116 int err;
1117
1118 if (debug_threads)
1119 debug_printf ("Found new lwp %d\n", lwpid);
1120
1121 err = linux_attach_lwp (ptid);
1122
1123 /* Be quiet if we simply raced with the thread exiting. EPERM
1124 is returned if the thread's task still exists, and is marked
1125 as exited or zombie, as well as other conditions, so in that
1126 case, confirm the status in /proc/PID/status. */
1127 if (err == ESRCH
1128 || (err == EPERM && linux_proc_pid_is_gone (lwpid)))
1129 {
1130 if (debug_threads)
1131 {
1132 debug_printf ("Cannot attach to lwp %d: "
1133 "thread is gone (%d: %s)\n",
1134 lwpid, err, strerror (err));
1135 }
1136 }
1137 else if (err != 0)
1138 {
1139 warning (_("Cannot attach to lwp %d: %s"),
1140 lwpid,
1141 linux_ptrace_attach_fail_reason_string (ptid, err));
1142 }
1143
1144 return 1;
1145 }
1146 return 0;
1147}
1148
500c1d85
PA
1149static void async_file_mark (void);
1150
e3deef73
LM
1151/* Attach to PID. If PID is the tgid, attach to it and all
1152 of its threads. */
1153
c52daf70 1154static int
a1928bad 1155linux_attach (unsigned long pid)
0d62e5e8 1156{
500c1d85
PA
1157 struct process_info *proc;
1158 struct thread_info *initial_thread;
7ae1a6a6
PA
1159 ptid_t ptid = ptid_build (pid, pid, 0);
1160 int err;
1161
e3deef73
LM
1162 /* Attach to PID. We will check for other threads
1163 soon. */
7ae1a6a6
PA
1164 err = linux_attach_lwp (ptid);
1165 if (err != 0)
1166 error ("Cannot attach to process %ld: %s",
8784d563 1167 pid, linux_ptrace_attach_fail_reason_string (ptid, err));
7ae1a6a6 1168
500c1d85 1169 proc = linux_add_process (pid, 1);
0d62e5e8 1170
500c1d85
PA
1171 /* Don't ignore the initial SIGSTOP if we just attached to this
1172 process. It will be collected by wait shortly. */
1173 initial_thread = find_thread_ptid (ptid_build (pid, pid, 0));
1174 initial_thread->last_resume_kind = resume_stop;
0d62e5e8 1175
8784d563
PA
1176 /* We must attach to every LWP. If /proc is mounted, use that to
1177 find them now. On the one hand, the inferior may be using raw
1178 clone instead of using pthreads. On the other hand, even if it
1179 is using pthreads, GDB may not be connected yet (thread_db needs
1180 to do symbol lookups, through qSymbol). Also, thread_db walks
1181 structures in the inferior's address space to find the list of
1182 threads/LWPs, and those structures may well be corrupted. Note
1183 that once thread_db is loaded, we'll still use it to list threads
1184 and associate pthread info with each LWP. */
1185 linux_proc_attach_tgid_threads (pid, attach_proc_task_lwp_callback);
500c1d85
PA
1186
1187 /* GDB will shortly read the xml target description for this
1188 process, to figure out the process' architecture. But the target
1189 description is only filled in when the first process/thread in
1190 the thread group reports its initial PTRACE_ATTACH SIGSTOP. Do
1191 that now, otherwise, if GDB is fast enough, it could read the
1192 target description _before_ that initial stop. */
1193 if (non_stop)
1194 {
1195 struct lwp_info *lwp;
1196 int wstat, lwpid;
1197 ptid_t pid_ptid = pid_to_ptid (pid);
1198
1199 lwpid = linux_wait_for_event_filtered (pid_ptid, pid_ptid,
1200 &wstat, __WALL);
1201 gdb_assert (lwpid > 0);
1202
1203 lwp = find_lwp_pid (pid_to_ptid (lwpid));
1204
1205 if (!WIFSTOPPED (wstat) || WSTOPSIG (wstat) != SIGSTOP)
1206 {
1207 lwp->status_pending_p = 1;
1208 lwp->status_pending = wstat;
1209 }
1210
1211 initial_thread->last_resume_kind = resume_continue;
1212
1213 async_file_mark ();
1214
1215 gdb_assert (proc->tdesc != NULL);
1216 }
1217
95954743
PA
1218 return 0;
1219}
1220
1221struct counter
1222{
1223 int pid;
1224 int count;
1225};
1226
1227static int
1228second_thread_of_pid_p (struct inferior_list_entry *entry, void *args)
1229{
9a3c8263 1230 struct counter *counter = (struct counter *) args;
95954743
PA
1231
1232 if (ptid_get_pid (entry->id) == counter->pid)
1233 {
1234 if (++counter->count > 1)
1235 return 1;
1236 }
d61ddec4 1237
da6d8c04
DJ
1238 return 0;
1239}
1240
95954743 1241static int
fa96cb38 1242last_thread_of_process_p (int pid)
95954743 1243{
95954743 1244 struct counter counter = { pid , 0 };
da6d8c04 1245
95954743
PA
1246 return (find_inferior (&all_threads,
1247 second_thread_of_pid_p, &counter) == NULL);
1248}
1249
da84f473
PA
1250/* Kill LWP. */
1251
1252static void
1253linux_kill_one_lwp (struct lwp_info *lwp)
1254{
d86d4aaf
DE
1255 struct thread_info *thr = get_lwp_thread (lwp);
1256 int pid = lwpid_of (thr);
da84f473
PA
1257
1258 /* PTRACE_KILL is unreliable. After stepping into a signal handler,
1259 there is no signal context, and ptrace(PTRACE_KILL) (or
1260 ptrace(PTRACE_CONT, SIGKILL), pretty much the same) acts like
1261 ptrace(CONT, pid, 0,0) and just resumes the tracee. A better
1262 alternative is to kill with SIGKILL. We only need one SIGKILL
1263 per process, not one for each thread. But since we still support
4a6ed09b
PA
1264 support debugging programs using raw clone without CLONE_THREAD,
1265 we send one for each thread. For years, we used PTRACE_KILL
1266 only, so we're being a bit paranoid about some old kernels where
1267 PTRACE_KILL might work better (dubious if there are any such, but
1268 that's why it's paranoia), so we try SIGKILL first, PTRACE_KILL
1269 second, and so we're fine everywhere. */
da84f473
PA
1270
1271 errno = 0;
69ff6be5 1272 kill_lwp (pid, SIGKILL);
da84f473 1273 if (debug_threads)
ce9e3fe7
PA
1274 {
1275 int save_errno = errno;
1276
1277 debug_printf ("LKL: kill_lwp (SIGKILL) %s, 0, 0 (%s)\n",
1278 target_pid_to_str (ptid_of (thr)),
1279 save_errno ? strerror (save_errno) : "OK");
1280 }
da84f473
PA
1281
1282 errno = 0;
b8e1b30e 1283 ptrace (PTRACE_KILL, pid, (PTRACE_TYPE_ARG3) 0, (PTRACE_TYPE_ARG4) 0);
da84f473 1284 if (debug_threads)
ce9e3fe7
PA
1285 {
1286 int save_errno = errno;
1287
1288 debug_printf ("LKL: PTRACE_KILL %s, 0, 0 (%s)\n",
1289 target_pid_to_str (ptid_of (thr)),
1290 save_errno ? strerror (save_errno) : "OK");
1291 }
da84f473
PA
1292}
1293
e76126e8
PA
1294/* Kill LWP and wait for it to die. */
1295
1296static void
1297kill_wait_lwp (struct lwp_info *lwp)
1298{
1299 struct thread_info *thr = get_lwp_thread (lwp);
1300 int pid = ptid_get_pid (ptid_of (thr));
1301 int lwpid = ptid_get_lwp (ptid_of (thr));
1302 int wstat;
1303 int res;
1304
1305 if (debug_threads)
1306 debug_printf ("kwl: killing lwp %d, for pid: %d\n", lwpid, pid);
1307
1308 do
1309 {
1310 linux_kill_one_lwp (lwp);
1311
1312 /* Make sure it died. Notes:
1313
1314 - The loop is most likely unnecessary.
1315
1316 - We don't use linux_wait_for_event as that could delete lwps
1317 while we're iterating over them. We're not interested in
1318 any pending status at this point, only in making sure all
1319 wait status on the kernel side are collected until the
1320 process is reaped.
1321
1322 - We don't use __WALL here as the __WALL emulation relies on
1323 SIGCHLD, and killing a stopped process doesn't generate
1324 one, nor an exit status.
1325 */
1326 res = my_waitpid (lwpid, &wstat, 0);
1327 if (res == -1 && errno == ECHILD)
1328 res = my_waitpid (lwpid, &wstat, __WCLONE);
1329 } while (res > 0 && WIFSTOPPED (wstat));
1330
586b02a9
PA
1331 /* Even if it was stopped, the child may have already disappeared.
1332 E.g., if it was killed by SIGKILL. */
1333 if (res < 0 && errno != ECHILD)
1334 perror_with_name ("kill_wait_lwp");
e76126e8
PA
1335}
1336
da84f473
PA
1337/* Callback for `find_inferior'. Kills an lwp of a given process,
1338 except the leader. */
95954743
PA
1339
1340static int
da84f473 1341kill_one_lwp_callback (struct inferior_list_entry *entry, void *args)
da6d8c04 1342{
0d62e5e8 1343 struct thread_info *thread = (struct thread_info *) entry;
54a0b537 1344 struct lwp_info *lwp = get_thread_lwp (thread);
95954743
PA
1345 int pid = * (int *) args;
1346
1347 if (ptid_get_pid (entry->id) != pid)
1348 return 0;
0d62e5e8 1349
fd500816
DJ
1350 /* We avoid killing the first thread here, because of a Linux kernel (at
1351 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
1352 the children get a chance to be reaped, it will remain a zombie
1353 forever. */
95954743 1354
d86d4aaf 1355 if (lwpid_of (thread) == pid)
95954743
PA
1356 {
1357 if (debug_threads)
87ce2a04
DE
1358 debug_printf ("lkop: is last of process %s\n",
1359 target_pid_to_str (entry->id));
95954743
PA
1360 return 0;
1361 }
fd500816 1362
e76126e8 1363 kill_wait_lwp (lwp);
95954743 1364 return 0;
da6d8c04
DJ
1365}
1366
95954743
PA
1367static int
1368linux_kill (int pid)
0d62e5e8 1369{
95954743 1370 struct process_info *process;
54a0b537 1371 struct lwp_info *lwp;
fd500816 1372
95954743
PA
1373 process = find_process_pid (pid);
1374 if (process == NULL)
1375 return -1;
9d606399 1376
f9e39928
PA
1377 /* If we're killing a running inferior, make sure it is stopped
1378 first, as PTRACE_KILL will not work otherwise. */
7984d532 1379 stop_all_lwps (0, NULL);
f9e39928 1380
da84f473 1381 find_inferior (&all_threads, kill_one_lwp_callback , &pid);
fd500816 1382
54a0b537 1383 /* See the comment in linux_kill_one_lwp. We did not kill the first
fd500816 1384 thread in the list, so do so now. */
95954743 1385 lwp = find_lwp_pid (pid_to_ptid (pid));
bd99dc85 1386
784867a5 1387 if (lwp == NULL)
fd500816 1388 {
784867a5 1389 if (debug_threads)
d86d4aaf
DE
1390 debug_printf ("lk_1: cannot find lwp for pid: %d\n",
1391 pid);
784867a5
JK
1392 }
1393 else
e76126e8 1394 kill_wait_lwp (lwp);
2d717e4f 1395
8336d594 1396 the_target->mourn (process);
f9e39928
PA
1397
1398 /* Since we presently can only stop all lwps of all processes, we
1399 need to unstop lwps of other processes. */
7984d532 1400 unstop_all_lwps (0, NULL);
95954743 1401 return 0;
0d62e5e8
DJ
1402}
1403
9b224c5e
PA
1404/* Get pending signal of THREAD, for detaching purposes. This is the
1405 signal the thread last stopped for, which we need to deliver to the
1406 thread when detaching, otherwise, it'd be suppressed/lost. */
1407
1408static int
1409get_detach_signal (struct thread_info *thread)
1410{
a493e3e2 1411 enum gdb_signal signo = GDB_SIGNAL_0;
9b224c5e
PA
1412 int status;
1413 struct lwp_info *lp = get_thread_lwp (thread);
1414
1415 if (lp->status_pending_p)
1416 status = lp->status_pending;
1417 else
1418 {
1419 /* If the thread had been suspended by gdbserver, and it stopped
1420 cleanly, then it'll have stopped with SIGSTOP. But we don't
1421 want to deliver that SIGSTOP. */
1422 if (thread->last_status.kind != TARGET_WAITKIND_STOPPED
a493e3e2 1423 || thread->last_status.value.sig == GDB_SIGNAL_0)
9b224c5e
PA
1424 return 0;
1425
1426 /* Otherwise, we may need to deliver the signal we
1427 intercepted. */
1428 status = lp->last_status;
1429 }
1430
1431 if (!WIFSTOPPED (status))
1432 {
1433 if (debug_threads)
87ce2a04 1434 debug_printf ("GPS: lwp %s hasn't stopped: no pending signal\n",
d86d4aaf 1435 target_pid_to_str (ptid_of (thread)));
9b224c5e
PA
1436 return 0;
1437 }
1438
1439 /* Extended wait statuses aren't real SIGTRAPs. */
89a5711c 1440 if (WSTOPSIG (status) == SIGTRAP && linux_is_extended_waitstatus (status))
9b224c5e
PA
1441 {
1442 if (debug_threads)
87ce2a04
DE
1443 debug_printf ("GPS: lwp %s had stopped with extended "
1444 "status: no pending signal\n",
d86d4aaf 1445 target_pid_to_str (ptid_of (thread)));
9b224c5e
PA
1446 return 0;
1447 }
1448
2ea28649 1449 signo = gdb_signal_from_host (WSTOPSIG (status));
9b224c5e
PA
1450
1451 if (program_signals_p && !program_signals[signo])
1452 {
1453 if (debug_threads)
87ce2a04 1454 debug_printf ("GPS: lwp %s had signal %s, but it is in nopass state\n",
d86d4aaf 1455 target_pid_to_str (ptid_of (thread)),
87ce2a04 1456 gdb_signal_to_string (signo));
9b224c5e
PA
1457 return 0;
1458 }
1459 else if (!program_signals_p
1460 /* If we have no way to know which signals GDB does not
1461 want to have passed to the program, assume
1462 SIGTRAP/SIGINT, which is GDB's default. */
a493e3e2 1463 && (signo == GDB_SIGNAL_TRAP || signo == GDB_SIGNAL_INT))
9b224c5e
PA
1464 {
1465 if (debug_threads)
87ce2a04
DE
1466 debug_printf ("GPS: lwp %s had signal %s, "
1467 "but we don't know if we should pass it. "
1468 "Default to not.\n",
d86d4aaf 1469 target_pid_to_str (ptid_of (thread)),
87ce2a04 1470 gdb_signal_to_string (signo));
9b224c5e
PA
1471 return 0;
1472 }
1473 else
1474 {
1475 if (debug_threads)
87ce2a04 1476 debug_printf ("GPS: lwp %s has pending signal %s: delivering it.\n",
d86d4aaf 1477 target_pid_to_str (ptid_of (thread)),
87ce2a04 1478 gdb_signal_to_string (signo));
9b224c5e
PA
1479
1480 return WSTOPSIG (status);
1481 }
1482}
1483
ced2dffb
PA
1484/* Detach from LWP. */
1485
1486static void
1487linux_detach_one_lwp (struct lwp_info *lwp)
6ad8ae5c 1488{
ced2dffb 1489 struct thread_info *thread = get_lwp_thread (lwp);
9b224c5e 1490 int sig;
ced2dffb 1491 int lwpid;
6ad8ae5c 1492
9b224c5e 1493 /* If there is a pending SIGSTOP, get rid of it. */
54a0b537 1494 if (lwp->stop_expected)
ae13219e 1495 {
9b224c5e 1496 if (debug_threads)
87ce2a04 1497 debug_printf ("Sending SIGCONT to %s\n",
d86d4aaf 1498 target_pid_to_str (ptid_of (thread)));
9b224c5e 1499
d86d4aaf 1500 kill_lwp (lwpid_of (thread), SIGCONT);
54a0b537 1501 lwp->stop_expected = 0;
ae13219e
DJ
1502 }
1503
9b224c5e
PA
1504 /* Pass on any pending signal for this thread. */
1505 sig = get_detach_signal (thread);
1506
ced2dffb
PA
1507 /* Preparing to resume may try to write registers, and fail if the
1508 lwp is zombie. If that happens, ignore the error. We'll handle
1509 it below, when detach fails with ESRCH. */
1510 TRY
1511 {
1512 /* Flush any pending changes to the process's registers. */
1513 regcache_invalidate_thread (thread);
1514
1515 /* Finally, let it resume. */
1516 if (the_low_target.prepare_to_resume != NULL)
1517 the_low_target.prepare_to_resume (lwp);
1518 }
1519 CATCH (ex, RETURN_MASK_ERROR)
1520 {
1521 if (!check_ptrace_stopped_lwp_gone (lwp))
1522 throw_exception (ex);
1523 }
1524 END_CATCH
1525
1526 lwpid = lwpid_of (thread);
1527 if (ptrace (PTRACE_DETACH, lwpid, (PTRACE_TYPE_ARG3) 0,
b8e1b30e 1528 (PTRACE_TYPE_ARG4) (long) sig) < 0)
ced2dffb
PA
1529 {
1530 int save_errno = errno;
1531
1532 /* We know the thread exists, so ESRCH must mean the lwp is
1533 zombie. This can happen if one of the already-detached
1534 threads exits the whole thread group. In that case we're
1535 still attached, and must reap the lwp. */
1536 if (save_errno == ESRCH)
1537 {
1538 int ret, status;
1539
1540 ret = my_waitpid (lwpid, &status, __WALL);
1541 if (ret == -1)
1542 {
1543 warning (_("Couldn't reap LWP %d while detaching: %s"),
1544 lwpid, strerror (errno));
1545 }
1546 else if (!WIFEXITED (status) && !WIFSIGNALED (status))
1547 {
1548 warning (_("Reaping LWP %d while detaching "
1549 "returned unexpected status 0x%x"),
1550 lwpid, status);
1551 }
1552 }
1553 else
1554 {
1555 error (_("Can't detach %s: %s"),
1556 target_pid_to_str (ptid_of (thread)),
1557 strerror (save_errno));
1558 }
1559 }
1560 else if (debug_threads)
1561 {
1562 debug_printf ("PTRACE_DETACH (%s, %s, 0) (OK)\n",
1563 target_pid_to_str (ptid_of (thread)),
1564 strsignal (sig));
1565 }
bd99dc85
PA
1566
1567 delete_lwp (lwp);
ced2dffb
PA
1568}
1569
1570/* Callback for find_inferior. Detaches from non-leader threads of a
1571 given process. */
1572
1573static int
1574linux_detach_lwp_callback (struct inferior_list_entry *entry, void *args)
1575{
1576 struct thread_info *thread = (struct thread_info *) entry;
1577 struct lwp_info *lwp = get_thread_lwp (thread);
1578 int pid = *(int *) args;
1579 int lwpid = lwpid_of (thread);
1580
1581 /* Skip other processes. */
1582 if (ptid_get_pid (entry->id) != pid)
1583 return 0;
1584
1585 /* We don't actually detach from the thread group leader just yet.
1586 If the thread group exits, we must reap the zombie clone lwps
1587 before we're able to reap the leader. */
1588 if (ptid_get_pid (entry->id) == lwpid)
1589 return 0;
1590
1591 linux_detach_one_lwp (lwp);
95954743 1592 return 0;
6ad8ae5c
DJ
1593}
1594
95954743
PA
1595static int
1596linux_detach (int pid)
1597{
1598 struct process_info *process;
ced2dffb 1599 struct lwp_info *main_lwp;
95954743
PA
1600
1601 process = find_process_pid (pid);
1602 if (process == NULL)
1603 return -1;
1604
863d01bd
PA
1605 /* As there's a step over already in progress, let it finish first,
1606 otherwise nesting a stabilize_threads operation on top gets real
1607 messy. */
1608 complete_ongoing_step_over ();
1609
f9e39928
PA
1610 /* Stop all threads before detaching. First, ptrace requires that
1611 the thread is stopped to sucessfully detach. Second, thread_db
1612 may need to uninstall thread event breakpoints from memory, which
1613 only works with a stopped process anyway. */
7984d532 1614 stop_all_lwps (0, NULL);
f9e39928 1615
ca5c370d 1616#ifdef USE_THREAD_DB
8336d594 1617 thread_db_detach (process);
ca5c370d
PA
1618#endif
1619
fa593d66
PA
1620 /* Stabilize threads (move out of jump pads). */
1621 stabilize_threads ();
1622
ced2dffb
PA
1623 /* Detach from the clone lwps first. If the thread group exits just
1624 while we're detaching, we must reap the clone lwps before we're
1625 able to reap the leader. */
1626 find_inferior (&all_threads, linux_detach_lwp_callback, &pid);
1627
1628 main_lwp = find_lwp_pid (pid_to_ptid (pid));
1629 linux_detach_one_lwp (main_lwp);
8336d594
PA
1630
1631 the_target->mourn (process);
f9e39928
PA
1632
1633 /* Since we presently can only stop all lwps of all processes, we
1634 need to unstop lwps of other processes. */
7984d532 1635 unstop_all_lwps (0, NULL);
f9e39928
PA
1636 return 0;
1637}
1638
1639/* Remove all LWPs that belong to process PROC from the lwp list. */
1640
1641static int
1642delete_lwp_callback (struct inferior_list_entry *entry, void *proc)
1643{
d86d4aaf
DE
1644 struct thread_info *thread = (struct thread_info *) entry;
1645 struct lwp_info *lwp = get_thread_lwp (thread);
9a3c8263 1646 struct process_info *process = (struct process_info *) proc;
f9e39928 1647
d86d4aaf 1648 if (pid_of (thread) == pid_of (process))
f9e39928
PA
1649 delete_lwp (lwp);
1650
dd6953e1 1651 return 0;
6ad8ae5c
DJ
1652}
1653
8336d594
PA
1654static void
1655linux_mourn (struct process_info *process)
1656{
1657 struct process_info_private *priv;
1658
1659#ifdef USE_THREAD_DB
1660 thread_db_mourn (process);
1661#endif
1662
d86d4aaf 1663 find_inferior (&all_threads, delete_lwp_callback, process);
f9e39928 1664
8336d594 1665 /* Freeing all private data. */
fe978cb0 1666 priv = process->priv;
8336d594
PA
1667 free (priv->arch_private);
1668 free (priv);
fe978cb0 1669 process->priv = NULL;
505106cd
PA
1670
1671 remove_process (process);
8336d594
PA
1672}
1673
444d6139 1674static void
95954743 1675linux_join (int pid)
444d6139 1676{
444d6139
PA
1677 int status, ret;
1678
1679 do {
95954743 1680 ret = my_waitpid (pid, &status, 0);
444d6139
PA
1681 if (WIFEXITED (status) || WIFSIGNALED (status))
1682 break;
1683 } while (ret != -1 || errno != ECHILD);
1684}
1685
6ad8ae5c 1686/* Return nonzero if the given thread is still alive. */
0d62e5e8 1687static int
95954743 1688linux_thread_alive (ptid_t ptid)
0d62e5e8 1689{
95954743
PA
1690 struct lwp_info *lwp = find_lwp_pid (ptid);
1691
1692 /* We assume we always know if a thread exits. If a whole process
1693 exited but we still haven't been able to report it to GDB, we'll
1694 hold on to the last lwp of the dead process. */
1695 if (lwp != NULL)
00db26fa 1696 return !lwp_is_marked_dead (lwp);
0d62e5e8
DJ
1697 else
1698 return 0;
1699}
1700
582511be
PA
1701/* Return 1 if this lwp still has an interesting status pending. If
1702 not (e.g., it had stopped for a breakpoint that is gone), return
1703 false. */
1704
1705static int
1706thread_still_has_status_pending_p (struct thread_info *thread)
1707{
1708 struct lwp_info *lp = get_thread_lwp (thread);
1709
1710 if (!lp->status_pending_p)
1711 return 0;
1712
582511be 1713 if (thread->last_resume_kind != resume_stop
15c66dd6
PA
1714 && (lp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT
1715 || lp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT))
582511be
PA
1716 {
1717 struct thread_info *saved_thread;
1718 CORE_ADDR pc;
1719 int discard = 0;
1720
1721 gdb_assert (lp->last_status != 0);
1722
1723 pc = get_pc (lp);
1724
1725 saved_thread = current_thread;
1726 current_thread = thread;
1727
1728 if (pc != lp->stop_pc)
1729 {
1730 if (debug_threads)
1731 debug_printf ("PC of %ld changed\n",
1732 lwpid_of (thread));
1733 discard = 1;
1734 }
3e572f71
PA
1735
1736#if !USE_SIGTRAP_SIGINFO
15c66dd6 1737 else if (lp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT
582511be
PA
1738 && !(*the_low_target.breakpoint_at) (pc))
1739 {
1740 if (debug_threads)
1741 debug_printf ("previous SW breakpoint of %ld gone\n",
1742 lwpid_of (thread));
1743 discard = 1;
1744 }
15c66dd6 1745 else if (lp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT
582511be
PA
1746 && !hardware_breakpoint_inserted_here (pc))
1747 {
1748 if (debug_threads)
1749 debug_printf ("previous HW breakpoint of %ld gone\n",
1750 lwpid_of (thread));
1751 discard = 1;
1752 }
3e572f71 1753#endif
582511be
PA
1754
1755 current_thread = saved_thread;
1756
1757 if (discard)
1758 {
1759 if (debug_threads)
1760 debug_printf ("discarding pending breakpoint status\n");
1761 lp->status_pending_p = 0;
1762 return 0;
1763 }
1764 }
1765
1766 return 1;
1767}
1768
a681f9c9
PA
1769/* Returns true if LWP is resumed from the client's perspective. */
1770
1771static int
1772lwp_resumed (struct lwp_info *lwp)
1773{
1774 struct thread_info *thread = get_lwp_thread (lwp);
1775
1776 if (thread->last_resume_kind != resume_stop)
1777 return 1;
1778
1779 /* Did gdb send us a `vCont;t', but we haven't reported the
1780 corresponding stop to gdb yet? If so, the thread is still
1781 resumed/running from gdb's perspective. */
1782 if (thread->last_resume_kind == resume_stop
1783 && thread->last_status.kind == TARGET_WAITKIND_IGNORE)
1784 return 1;
1785
1786 return 0;
1787}
1788
6bf5e0ba 1789/* Return 1 if this lwp has an interesting status pending. */
611cb4a5 1790static int
d50171e4 1791status_pending_p_callback (struct inferior_list_entry *entry, void *arg)
0d62e5e8 1792{
d86d4aaf 1793 struct thread_info *thread = (struct thread_info *) entry;
582511be 1794 struct lwp_info *lp = get_thread_lwp (thread);
95954743
PA
1795 ptid_t ptid = * (ptid_t *) arg;
1796
1797 /* Check if we're only interested in events from a specific process
afa8d396
PA
1798 or a specific LWP. */
1799 if (!ptid_match (ptid_of (thread), ptid))
95954743 1800 return 0;
0d62e5e8 1801
a681f9c9
PA
1802 if (!lwp_resumed (lp))
1803 return 0;
1804
582511be
PA
1805 if (lp->status_pending_p
1806 && !thread_still_has_status_pending_p (thread))
1807 {
1808 linux_resume_one_lwp (lp, lp->stepping, GDB_SIGNAL_0, NULL);
1809 return 0;
1810 }
0d62e5e8 1811
582511be 1812 return lp->status_pending_p;
0d62e5e8
DJ
1813}
1814
95954743
PA
1815static int
1816same_lwp (struct inferior_list_entry *entry, void *data)
1817{
1818 ptid_t ptid = *(ptid_t *) data;
1819 int lwp;
1820
1821 if (ptid_get_lwp (ptid) != 0)
1822 lwp = ptid_get_lwp (ptid);
1823 else
1824 lwp = ptid_get_pid (ptid);
1825
1826 if (ptid_get_lwp (entry->id) == lwp)
1827 return 1;
1828
1829 return 0;
1830}
1831
1832struct lwp_info *
1833find_lwp_pid (ptid_t ptid)
1834{
d86d4aaf
DE
1835 struct inferior_list_entry *thread
1836 = find_inferior (&all_threads, same_lwp, &ptid);
1837
1838 if (thread == NULL)
1839 return NULL;
1840
1841 return get_thread_lwp ((struct thread_info *) thread);
95954743
PA
1842}
1843
fa96cb38 1844/* Return the number of known LWPs in the tgid given by PID. */
0d62e5e8 1845
fa96cb38
PA
1846static int
1847num_lwps (int pid)
1848{
1849 struct inferior_list_entry *inf, *tmp;
1850 int count = 0;
0d62e5e8 1851
fa96cb38 1852 ALL_INFERIORS (&all_threads, inf, tmp)
24a09b5f 1853 {
fa96cb38
PA
1854 if (ptid_get_pid (inf->id) == pid)
1855 count++;
24a09b5f 1856 }
3aee8918 1857
fa96cb38
PA
1858 return count;
1859}
d61ddec4 1860
6d4ee8c6
GB
1861/* The arguments passed to iterate_over_lwps. */
1862
1863struct iterate_over_lwps_args
1864{
1865 /* The FILTER argument passed to iterate_over_lwps. */
1866 ptid_t filter;
1867
1868 /* The CALLBACK argument passed to iterate_over_lwps. */
1869 iterate_over_lwps_ftype *callback;
1870
1871 /* The DATA argument passed to iterate_over_lwps. */
1872 void *data;
1873};
1874
1875/* Callback for find_inferior used by iterate_over_lwps to filter
1876 calls to the callback supplied to that function. Returning a
1877 nonzero value causes find_inferiors to stop iterating and return
1878 the current inferior_list_entry. Returning zero indicates that
1879 find_inferiors should continue iterating. */
1880
1881static int
1882iterate_over_lwps_filter (struct inferior_list_entry *entry, void *args_p)
1883{
1884 struct iterate_over_lwps_args *args
1885 = (struct iterate_over_lwps_args *) args_p;
1886
1887 if (ptid_match (entry->id, args->filter))
1888 {
1889 struct thread_info *thr = (struct thread_info *) entry;
1890 struct lwp_info *lwp = get_thread_lwp (thr);
1891
1892 return (*args->callback) (lwp, args->data);
1893 }
1894
1895 return 0;
1896}
1897
1898/* See nat/linux-nat.h. */
1899
1900struct lwp_info *
1901iterate_over_lwps (ptid_t filter,
1902 iterate_over_lwps_ftype callback,
1903 void *data)
1904{
1905 struct iterate_over_lwps_args args = {filter, callback, data};
1906 struct inferior_list_entry *entry;
1907
1908 entry = find_inferior (&all_threads, iterate_over_lwps_filter, &args);
1909 if (entry == NULL)
1910 return NULL;
1911
1912 return get_thread_lwp ((struct thread_info *) entry);
1913}
1914
fa96cb38
PA
1915/* Detect zombie thread group leaders, and "exit" them. We can't reap
1916 their exits until all other threads in the group have exited. */
c3adc08c 1917
fa96cb38
PA
1918static void
1919check_zombie_leaders (void)
1920{
1921 struct process_info *proc, *tmp;
c3adc08c 1922
fa96cb38 1923 ALL_PROCESSES (proc, tmp)
c3adc08c 1924 {
fa96cb38
PA
1925 pid_t leader_pid = pid_of (proc);
1926 struct lwp_info *leader_lp;
c3adc08c 1927
fa96cb38 1928 leader_lp = find_lwp_pid (pid_to_ptid (leader_pid));
c3adc08c 1929
fa96cb38
PA
1930 if (debug_threads)
1931 debug_printf ("leader_pid=%d, leader_lp!=NULL=%d, "
1932 "num_lwps=%d, zombie=%d\n",
1933 leader_pid, leader_lp!= NULL, num_lwps (leader_pid),
1934 linux_proc_pid_is_zombie (leader_pid));
1935
94585166 1936 if (leader_lp != NULL && !leader_lp->stopped
fa96cb38
PA
1937 /* Check if there are other threads in the group, as we may
1938 have raced with the inferior simply exiting. */
1939 && !last_thread_of_process_p (leader_pid)
1940 && linux_proc_pid_is_zombie (leader_pid))
1941 {
1942 /* A leader zombie can mean one of two things:
1943
1944 - It exited, and there's an exit status pending
1945 available, or only the leader exited (not the whole
1946 program). In the latter case, we can't waitpid the
1947 leader's exit status until all other threads are gone.
1948
1949 - There are 3 or more threads in the group, and a thread
1950 other than the leader exec'd. On an exec, the Linux
1951 kernel destroys all other threads (except the execing
1952 one) in the thread group, and resets the execing thread's
1953 tid to the tgid. No exit notification is sent for the
1954 execing thread -- from the ptracer's perspective, it
1955 appears as though the execing thread just vanishes.
1956 Until we reap all other threads except the leader and the
1957 execing thread, the leader will be zombie, and the
1958 execing thread will be in `D (disc sleep)'. As soon as
1959 all other threads are reaped, the execing thread changes
1960 it's tid to the tgid, and the previous (zombie) leader
1961 vanishes, giving place to the "new" leader. We could try
1962 distinguishing the exit and exec cases, by waiting once
1963 more, and seeing if something comes out, but it doesn't
1964 sound useful. The previous leader _does_ go away, and
1965 we'll re-add the new one once we see the exec event
1966 (which is just the same as what would happen if the
1967 previous leader did exit voluntarily before some other
1968 thread execs). */
c3adc08c 1969
fa96cb38
PA
1970 if (debug_threads)
1971 fprintf (stderr,
1972 "CZL: Thread group leader %d zombie "
1973 "(it exited, or another thread execd).\n",
1974 leader_pid);
c3adc08c 1975
fa96cb38 1976 delete_lwp (leader_lp);
c3adc08c
PA
1977 }
1978 }
fa96cb38 1979}
c3adc08c 1980
fa96cb38
PA
1981/* Callback for `find_inferior'. Returns the first LWP that is not
1982 stopped. ARG is a PTID filter. */
d50171e4 1983
fa96cb38
PA
1984static int
1985not_stopped_callback (struct inferior_list_entry *entry, void *arg)
1986{
1987 struct thread_info *thr = (struct thread_info *) entry;
1988 struct lwp_info *lwp;
1989 ptid_t filter = *(ptid_t *) arg;
47c0c975 1990
fa96cb38
PA
1991 if (!ptid_match (ptid_of (thr), filter))
1992 return 0;
bd99dc85 1993
fa96cb38
PA
1994 lwp = get_thread_lwp (thr);
1995 if (!lwp->stopped)
1996 return 1;
1997
1998 return 0;
0d62e5e8 1999}
611cb4a5 2000
863d01bd
PA
2001/* Increment LWP's suspend count. */
2002
2003static void
2004lwp_suspended_inc (struct lwp_info *lwp)
2005{
2006 lwp->suspended++;
2007
2008 if (debug_threads && lwp->suspended > 4)
2009 {
2010 struct thread_info *thread = get_lwp_thread (lwp);
2011
2012 debug_printf ("LWP %ld has a suspiciously high suspend count,"
2013 " suspended=%d\n", lwpid_of (thread), lwp->suspended);
2014 }
2015}
2016
2017/* Decrement LWP's suspend count. */
2018
2019static void
2020lwp_suspended_decr (struct lwp_info *lwp)
2021{
2022 lwp->suspended--;
2023
2024 if (lwp->suspended < 0)
2025 {
2026 struct thread_info *thread = get_lwp_thread (lwp);
2027
2028 internal_error (__FILE__, __LINE__,
2029 "unsuspend LWP %ld, suspended=%d\n", lwpid_of (thread),
2030 lwp->suspended);
2031 }
2032}
2033
219f2f23
PA
2034/* This function should only be called if the LWP got a SIGTRAP.
2035
2036 Handle any tracepoint steps or hits. Return true if a tracepoint
2037 event was handled, 0 otherwise. */
2038
2039static int
2040handle_tracepoints (struct lwp_info *lwp)
2041{
2042 struct thread_info *tinfo = get_lwp_thread (lwp);
2043 int tpoint_related_event = 0;
2044
582511be
PA
2045 gdb_assert (lwp->suspended == 0);
2046
7984d532
PA
2047 /* If this tracepoint hit causes a tracing stop, we'll immediately
2048 uninsert tracepoints. To do this, we temporarily pause all
2049 threads, unpatch away, and then unpause threads. We need to make
2050 sure the unpausing doesn't resume LWP too. */
863d01bd 2051 lwp_suspended_inc (lwp);
7984d532 2052
219f2f23
PA
2053 /* And we need to be sure that any all-threads-stopping doesn't try
2054 to move threads out of the jump pads, as it could deadlock the
2055 inferior (LWP could be in the jump pad, maybe even holding the
2056 lock.) */
2057
2058 /* Do any necessary step collect actions. */
2059 tpoint_related_event |= tracepoint_finished_step (tinfo, lwp->stop_pc);
2060
fa593d66
PA
2061 tpoint_related_event |= handle_tracepoint_bkpts (tinfo, lwp->stop_pc);
2062
219f2f23
PA
2063 /* See if we just hit a tracepoint and do its main collect
2064 actions. */
2065 tpoint_related_event |= tracepoint_was_hit (tinfo, lwp->stop_pc);
2066
863d01bd 2067 lwp_suspended_decr (lwp);
7984d532
PA
2068
2069 gdb_assert (lwp->suspended == 0);
fa593d66 2070 gdb_assert (!stabilizing_threads || lwp->collecting_fast_tracepoint);
7984d532 2071
219f2f23
PA
2072 if (tpoint_related_event)
2073 {
2074 if (debug_threads)
87ce2a04 2075 debug_printf ("got a tracepoint event\n");
219f2f23
PA
2076 return 1;
2077 }
2078
2079 return 0;
2080}
2081
fa593d66
PA
2082/* Convenience wrapper. Returns true if LWP is presently collecting a
2083 fast tracepoint. */
2084
2085static int
2086linux_fast_tracepoint_collecting (struct lwp_info *lwp,
2087 struct fast_tpoint_collect_status *status)
2088{
2089 CORE_ADDR thread_area;
d86d4aaf 2090 struct thread_info *thread = get_lwp_thread (lwp);
fa593d66
PA
2091
2092 if (the_low_target.get_thread_area == NULL)
2093 return 0;
2094
2095 /* Get the thread area address. This is used to recognize which
2096 thread is which when tracing with the in-process agent library.
2097 We don't read anything from the address, and treat it as opaque;
2098 it's the address itself that we assume is unique per-thread. */
d86d4aaf 2099 if ((*the_low_target.get_thread_area) (lwpid_of (thread), &thread_area) == -1)
fa593d66
PA
2100 return 0;
2101
2102 return fast_tracepoint_collecting (thread_area, lwp->stop_pc, status);
2103}
2104
2105/* The reason we resume in the caller, is because we want to be able
2106 to pass lwp->status_pending as WSTAT, and we need to clear
2107 status_pending_p before resuming, otherwise, linux_resume_one_lwp
2108 refuses to resume. */
2109
2110static int
2111maybe_move_out_of_jump_pad (struct lwp_info *lwp, int *wstat)
2112{
0bfdf32f 2113 struct thread_info *saved_thread;
fa593d66 2114
0bfdf32f
GB
2115 saved_thread = current_thread;
2116 current_thread = get_lwp_thread (lwp);
fa593d66
PA
2117
2118 if ((wstat == NULL
2119 || (WIFSTOPPED (*wstat) && WSTOPSIG (*wstat) != SIGTRAP))
2120 && supports_fast_tracepoints ()
58b4daa5 2121 && agent_loaded_p ())
fa593d66
PA
2122 {
2123 struct fast_tpoint_collect_status status;
2124 int r;
2125
2126 if (debug_threads)
87ce2a04
DE
2127 debug_printf ("Checking whether LWP %ld needs to move out of the "
2128 "jump pad.\n",
0bfdf32f 2129 lwpid_of (current_thread));
fa593d66
PA
2130
2131 r = linux_fast_tracepoint_collecting (lwp, &status);
2132
2133 if (wstat == NULL
2134 || (WSTOPSIG (*wstat) != SIGILL
2135 && WSTOPSIG (*wstat) != SIGFPE
2136 && WSTOPSIG (*wstat) != SIGSEGV
2137 && WSTOPSIG (*wstat) != SIGBUS))
2138 {
2139 lwp->collecting_fast_tracepoint = r;
2140
2141 if (r != 0)
2142 {
2143 if (r == 1 && lwp->exit_jump_pad_bkpt == NULL)
2144 {
2145 /* Haven't executed the original instruction yet.
2146 Set breakpoint there, and wait till it's hit,
2147 then single-step until exiting the jump pad. */
2148 lwp->exit_jump_pad_bkpt
2149 = set_breakpoint_at (status.adjusted_insn_addr, NULL);
2150 }
2151
2152 if (debug_threads)
87ce2a04
DE
2153 debug_printf ("Checking whether LWP %ld needs to move out of "
2154 "the jump pad...it does\n",
0bfdf32f
GB
2155 lwpid_of (current_thread));
2156 current_thread = saved_thread;
fa593d66
PA
2157
2158 return 1;
2159 }
2160 }
2161 else
2162 {
2163 /* If we get a synchronous signal while collecting, *and*
2164 while executing the (relocated) original instruction,
2165 reset the PC to point at the tpoint address, before
2166 reporting to GDB. Otherwise, it's an IPA lib bug: just
2167 report the signal to GDB, and pray for the best. */
2168
2169 lwp->collecting_fast_tracepoint = 0;
2170
2171 if (r != 0
2172 && (status.adjusted_insn_addr <= lwp->stop_pc
2173 && lwp->stop_pc < status.adjusted_insn_addr_end))
2174 {
2175 siginfo_t info;
2176 struct regcache *regcache;
2177
2178 /* The si_addr on a few signals references the address
2179 of the faulting instruction. Adjust that as
2180 well. */
2181 if ((WSTOPSIG (*wstat) == SIGILL
2182 || WSTOPSIG (*wstat) == SIGFPE
2183 || WSTOPSIG (*wstat) == SIGBUS
2184 || WSTOPSIG (*wstat) == SIGSEGV)
0bfdf32f 2185 && ptrace (PTRACE_GETSIGINFO, lwpid_of (current_thread),
b8e1b30e 2186 (PTRACE_TYPE_ARG3) 0, &info) == 0
fa593d66
PA
2187 /* Final check just to make sure we don't clobber
2188 the siginfo of non-kernel-sent signals. */
2189 && (uintptr_t) info.si_addr == lwp->stop_pc)
2190 {
2191 info.si_addr = (void *) (uintptr_t) status.tpoint_addr;
0bfdf32f 2192 ptrace (PTRACE_SETSIGINFO, lwpid_of (current_thread),
b8e1b30e 2193 (PTRACE_TYPE_ARG3) 0, &info);
fa593d66
PA
2194 }
2195
0bfdf32f 2196 regcache = get_thread_regcache (current_thread, 1);
fa593d66
PA
2197 (*the_low_target.set_pc) (regcache, status.tpoint_addr);
2198 lwp->stop_pc = status.tpoint_addr;
2199
2200 /* Cancel any fast tracepoint lock this thread was
2201 holding. */
2202 force_unlock_trace_buffer ();
2203 }
2204
2205 if (lwp->exit_jump_pad_bkpt != NULL)
2206 {
2207 if (debug_threads)
87ce2a04
DE
2208 debug_printf ("Cancelling fast exit-jump-pad: removing bkpt. "
2209 "stopping all threads momentarily.\n");
fa593d66
PA
2210
2211 stop_all_lwps (1, lwp);
fa593d66
PA
2212
2213 delete_breakpoint (lwp->exit_jump_pad_bkpt);
2214 lwp->exit_jump_pad_bkpt = NULL;
2215
2216 unstop_all_lwps (1, lwp);
2217
2218 gdb_assert (lwp->suspended >= 0);
2219 }
2220 }
2221 }
2222
2223 if (debug_threads)
87ce2a04
DE
2224 debug_printf ("Checking whether LWP %ld needs to move out of the "
2225 "jump pad...no\n",
0bfdf32f 2226 lwpid_of (current_thread));
0cccb683 2227
0bfdf32f 2228 current_thread = saved_thread;
fa593d66
PA
2229 return 0;
2230}
2231
2232/* Enqueue one signal in the "signals to report later when out of the
2233 jump pad" list. */
2234
2235static void
2236enqueue_one_deferred_signal (struct lwp_info *lwp, int *wstat)
2237{
2238 struct pending_signals *p_sig;
d86d4aaf 2239 struct thread_info *thread = get_lwp_thread (lwp);
fa593d66
PA
2240
2241 if (debug_threads)
87ce2a04 2242 debug_printf ("Deferring signal %d for LWP %ld.\n",
d86d4aaf 2243 WSTOPSIG (*wstat), lwpid_of (thread));
fa593d66
PA
2244
2245 if (debug_threads)
2246 {
2247 struct pending_signals *sig;
2248
2249 for (sig = lwp->pending_signals_to_report;
2250 sig != NULL;
2251 sig = sig->prev)
87ce2a04
DE
2252 debug_printf (" Already queued %d\n",
2253 sig->signal);
fa593d66 2254
87ce2a04 2255 debug_printf (" (no more currently queued signals)\n");
fa593d66
PA
2256 }
2257
1a981360
PA
2258 /* Don't enqueue non-RT signals if they are already in the deferred
2259 queue. (SIGSTOP being the easiest signal to see ending up here
2260 twice) */
2261 if (WSTOPSIG (*wstat) < __SIGRTMIN)
2262 {
2263 struct pending_signals *sig;
2264
2265 for (sig = lwp->pending_signals_to_report;
2266 sig != NULL;
2267 sig = sig->prev)
2268 {
2269 if (sig->signal == WSTOPSIG (*wstat))
2270 {
2271 if (debug_threads)
87ce2a04
DE
2272 debug_printf ("Not requeuing already queued non-RT signal %d"
2273 " for LWP %ld\n",
2274 sig->signal,
d86d4aaf 2275 lwpid_of (thread));
1a981360
PA
2276 return;
2277 }
2278 }
2279 }
2280
8d749320 2281 p_sig = XCNEW (struct pending_signals);
fa593d66
PA
2282 p_sig->prev = lwp->pending_signals_to_report;
2283 p_sig->signal = WSTOPSIG (*wstat);
8d749320 2284
d86d4aaf 2285 ptrace (PTRACE_GETSIGINFO, lwpid_of (thread), (PTRACE_TYPE_ARG3) 0,
56f7af9c 2286 &p_sig->info);
fa593d66
PA
2287
2288 lwp->pending_signals_to_report = p_sig;
2289}
2290
2291/* Dequeue one signal from the "signals to report later when out of
2292 the jump pad" list. */
2293
2294static int
2295dequeue_one_deferred_signal (struct lwp_info *lwp, int *wstat)
2296{
d86d4aaf
DE
2297 struct thread_info *thread = get_lwp_thread (lwp);
2298
fa593d66
PA
2299 if (lwp->pending_signals_to_report != NULL)
2300 {
2301 struct pending_signals **p_sig;
2302
2303 p_sig = &lwp->pending_signals_to_report;
2304 while ((*p_sig)->prev != NULL)
2305 p_sig = &(*p_sig)->prev;
2306
2307 *wstat = W_STOPCODE ((*p_sig)->signal);
2308 if ((*p_sig)->info.si_signo != 0)
d86d4aaf 2309 ptrace (PTRACE_SETSIGINFO, lwpid_of (thread), (PTRACE_TYPE_ARG3) 0,
56f7af9c 2310 &(*p_sig)->info);
fa593d66
PA
2311 free (*p_sig);
2312 *p_sig = NULL;
2313
2314 if (debug_threads)
87ce2a04 2315 debug_printf ("Reporting deferred signal %d for LWP %ld.\n",
d86d4aaf 2316 WSTOPSIG (*wstat), lwpid_of (thread));
fa593d66
PA
2317
2318 if (debug_threads)
2319 {
2320 struct pending_signals *sig;
2321
2322 for (sig = lwp->pending_signals_to_report;
2323 sig != NULL;
2324 sig = sig->prev)
87ce2a04
DE
2325 debug_printf (" Still queued %d\n",
2326 sig->signal);
fa593d66 2327
87ce2a04 2328 debug_printf (" (no more queued signals)\n");
fa593d66
PA
2329 }
2330
2331 return 1;
2332 }
2333
2334 return 0;
2335}
2336
582511be
PA
2337/* Fetch the possibly triggered data watchpoint info and store it in
2338 CHILD.
d50171e4 2339
582511be
PA
2340 On some archs, like x86, that use debug registers to set
2341 watchpoints, it's possible that the way to know which watched
2342 address trapped, is to check the register that is used to select
2343 which address to watch. Problem is, between setting the watchpoint
2344 and reading back which data address trapped, the user may change
2345 the set of watchpoints, and, as a consequence, GDB changes the
2346 debug registers in the inferior. To avoid reading back a stale
2347 stopped-data-address when that happens, we cache in LP the fact
2348 that a watchpoint trapped, and the corresponding data address, as
2349 soon as we see CHILD stop with a SIGTRAP. If GDB changes the debug
2350 registers meanwhile, we have the cached data we can rely on. */
d50171e4 2351
582511be
PA
2352static int
2353check_stopped_by_watchpoint (struct lwp_info *child)
2354{
2355 if (the_low_target.stopped_by_watchpoint != NULL)
d50171e4 2356 {
582511be 2357 struct thread_info *saved_thread;
d50171e4 2358
582511be
PA
2359 saved_thread = current_thread;
2360 current_thread = get_lwp_thread (child);
2361
2362 if (the_low_target.stopped_by_watchpoint ())
d50171e4 2363 {
15c66dd6 2364 child->stop_reason = TARGET_STOPPED_BY_WATCHPOINT;
582511be
PA
2365
2366 if (the_low_target.stopped_data_address != NULL)
2367 child->stopped_data_address
2368 = the_low_target.stopped_data_address ();
2369 else
2370 child->stopped_data_address = 0;
d50171e4
PA
2371 }
2372
0bfdf32f 2373 current_thread = saved_thread;
d50171e4
PA
2374 }
2375
15c66dd6 2376 return child->stop_reason == TARGET_STOPPED_BY_WATCHPOINT;
c4d9ceb6
YQ
2377}
2378
de0d863e
DB
2379/* Return the ptrace options that we want to try to enable. */
2380
2381static int
2382linux_low_ptrace_options (int attached)
2383{
2384 int options = 0;
2385
2386 if (!attached)
2387 options |= PTRACE_O_EXITKILL;
2388
2389 if (report_fork_events)
2390 options |= PTRACE_O_TRACEFORK;
2391
c269dbdb
DB
2392 if (report_vfork_events)
2393 options |= (PTRACE_O_TRACEVFORK | PTRACE_O_TRACEVFORKDONE);
2394
94585166
DB
2395 if (report_exec_events)
2396 options |= PTRACE_O_TRACEEXEC;
2397
82075af2
JS
2398 options |= PTRACE_O_TRACESYSGOOD;
2399
de0d863e
DB
2400 return options;
2401}
2402
fa96cb38
PA
2403/* Do low-level handling of the event, and check if we should go on
2404 and pass it to caller code. Return the affected lwp if we are, or
2405 NULL otherwise. */
2406
2407static struct lwp_info *
582511be 2408linux_low_filter_event (int lwpid, int wstat)
fa96cb38
PA
2409{
2410 struct lwp_info *child;
2411 struct thread_info *thread;
582511be 2412 int have_stop_pc = 0;
fa96cb38
PA
2413
2414 child = find_lwp_pid (pid_to_ptid (lwpid));
2415
94585166
DB
2416 /* Check for stop events reported by a process we didn't already
2417 know about - anything not already in our LWP list.
2418
2419 If we're expecting to receive stopped processes after
2420 fork, vfork, and clone events, then we'll just add the
2421 new one to our list and go back to waiting for the event
2422 to be reported - the stopped process might be returned
2423 from waitpid before or after the event is.
2424
2425 But note the case of a non-leader thread exec'ing after the
2426 leader having exited, and gone from our lists (because
2427 check_zombie_leaders deleted it). The non-leader thread
2428 changes its tid to the tgid. */
2429
2430 if (WIFSTOPPED (wstat) && child == NULL && WSTOPSIG (wstat) == SIGTRAP
2431 && linux_ptrace_get_extended_event (wstat) == PTRACE_EVENT_EXEC)
2432 {
2433 ptid_t child_ptid;
2434
2435 /* A multi-thread exec after we had seen the leader exiting. */
2436 if (debug_threads)
2437 {
2438 debug_printf ("LLW: Re-adding thread group leader LWP %d"
2439 "after exec.\n", lwpid);
2440 }
2441
2442 child_ptid = ptid_build (lwpid, lwpid, 0);
2443 child = add_lwp (child_ptid);
2444 child->stopped = 1;
2445 current_thread = child->thread;
2446 }
2447
fa96cb38
PA
2448 /* If we didn't find a process, one of two things presumably happened:
2449 - A process we started and then detached from has exited. Ignore it.
2450 - A process we are controlling has forked and the new child's stop
2451 was reported to us by the kernel. Save its PID. */
2452 if (child == NULL && WIFSTOPPED (wstat))
2453 {
2454 add_to_pid_list (&stopped_pids, lwpid, wstat);
2455 return NULL;
2456 }
2457 else if (child == NULL)
2458 return NULL;
2459
2460 thread = get_lwp_thread (child);
2461
2462 child->stopped = 1;
2463
2464 child->last_status = wstat;
2465
582511be
PA
2466 /* Check if the thread has exited. */
2467 if ((WIFEXITED (wstat) || WIFSIGNALED (wstat)))
2468 {
2469 if (debug_threads)
2470 debug_printf ("LLFE: %d exited.\n", lwpid);
f50bf8e5
YQ
2471
2472 if (finish_step_over (child))
2473 {
2474 /* Unsuspend all other LWPs, and set them back running again. */
2475 unsuspend_all_lwps (child);
2476 }
2477
65706a29
PA
2478 /* If there is at least one more LWP, then the exit signal was
2479 not the end of the debugged application and should be
2480 ignored, unless GDB wants to hear about thread exits. */
2481 if (report_thread_events
2482 || last_thread_of_process_p (pid_of (thread)))
582511be 2483 {
65706a29
PA
2484 /* Since events are serialized to GDB core, and we can't
2485 report this one right now. Leave the status pending for
2486 the next time we're able to report it. */
2487 mark_lwp_dead (child, wstat);
2488 return child;
582511be
PA
2489 }
2490 else
2491 {
65706a29
PA
2492 delete_lwp (child);
2493 return NULL;
582511be
PA
2494 }
2495 }
2496
2497 gdb_assert (WIFSTOPPED (wstat));
2498
fa96cb38
PA
2499 if (WIFSTOPPED (wstat))
2500 {
2501 struct process_info *proc;
2502
c06cbd92 2503 /* Architecture-specific setup after inferior is running. */
fa96cb38 2504 proc = find_process_pid (pid_of (thread));
c06cbd92 2505 if (proc->tdesc == NULL)
fa96cb38 2506 {
c06cbd92
YQ
2507 if (proc->attached)
2508 {
c06cbd92
YQ
2509 /* This needs to happen after we have attached to the
2510 inferior and it is stopped for the first time, but
2511 before we access any inferior registers. */
94585166 2512 linux_arch_setup_thread (thread);
c06cbd92
YQ
2513 }
2514 else
2515 {
2516 /* The process is started, but GDBserver will do
2517 architecture-specific setup after the program stops at
2518 the first instruction. */
2519 child->status_pending_p = 1;
2520 child->status_pending = wstat;
2521 return child;
2522 }
fa96cb38
PA
2523 }
2524 }
2525
fa96cb38
PA
2526 if (WIFSTOPPED (wstat) && child->must_set_ptrace_flags)
2527 {
beed38b8 2528 struct process_info *proc = find_process_pid (pid_of (thread));
de0d863e 2529 int options = linux_low_ptrace_options (proc->attached);
beed38b8 2530
de0d863e 2531 linux_enable_event_reporting (lwpid, options);
fa96cb38
PA
2532 child->must_set_ptrace_flags = 0;
2533 }
2534
82075af2
JS
2535 /* Always update syscall_state, even if it will be filtered later. */
2536 if (WIFSTOPPED (wstat) && WSTOPSIG (wstat) == SYSCALL_SIGTRAP)
2537 {
2538 child->syscall_state
2539 = (child->syscall_state == TARGET_WAITKIND_SYSCALL_ENTRY
2540 ? TARGET_WAITKIND_SYSCALL_RETURN
2541 : TARGET_WAITKIND_SYSCALL_ENTRY);
2542 }
2543 else
2544 {
2545 /* Almost all other ptrace-stops are known to be outside of system
2546 calls, with further exceptions in handle_extended_wait. */
2547 child->syscall_state = TARGET_WAITKIND_IGNORE;
2548 }
2549
e7ad2f14
PA
2550 /* Be careful to not overwrite stop_pc until save_stop_reason is
2551 called. */
fa96cb38 2552 if (WIFSTOPPED (wstat) && WSTOPSIG (wstat) == SIGTRAP
89a5711c 2553 && linux_is_extended_waitstatus (wstat))
fa96cb38 2554 {
582511be 2555 child->stop_pc = get_pc (child);
94585166 2556 if (handle_extended_wait (&child, wstat))
de0d863e
DB
2557 {
2558 /* The event has been handled, so just return without
2559 reporting it. */
2560 return NULL;
2561 }
fa96cb38
PA
2562 }
2563
80aea927 2564 if (linux_wstatus_maybe_breakpoint (wstat))
582511be 2565 {
e7ad2f14 2566 if (save_stop_reason (child))
582511be
PA
2567 have_stop_pc = 1;
2568 }
2569
2570 if (!have_stop_pc)
2571 child->stop_pc = get_pc (child);
2572
fa96cb38
PA
2573 if (WIFSTOPPED (wstat) && WSTOPSIG (wstat) == SIGSTOP
2574 && child->stop_expected)
2575 {
2576 if (debug_threads)
2577 debug_printf ("Expected stop.\n");
2578 child->stop_expected = 0;
2579
2580 if (thread->last_resume_kind == resume_stop)
2581 {
2582 /* We want to report the stop to the core. Treat the
2583 SIGSTOP as a normal event. */
2bf6fb9d
PA
2584 if (debug_threads)
2585 debug_printf ("LLW: resume_stop SIGSTOP caught for %s.\n",
2586 target_pid_to_str (ptid_of (thread)));
fa96cb38
PA
2587 }
2588 else if (stopping_threads != NOT_STOPPING_THREADS)
2589 {
2590 /* Stopping threads. We don't want this SIGSTOP to end up
582511be 2591 pending. */
2bf6fb9d
PA
2592 if (debug_threads)
2593 debug_printf ("LLW: SIGSTOP caught for %s "
2594 "while stopping threads.\n",
2595 target_pid_to_str (ptid_of (thread)));
fa96cb38
PA
2596 return NULL;
2597 }
2598 else
2599 {
2bf6fb9d
PA
2600 /* This is a delayed SIGSTOP. Filter out the event. */
2601 if (debug_threads)
2602 debug_printf ("LLW: %s %s, 0, 0 (discard delayed SIGSTOP)\n",
2603 child->stepping ? "step" : "continue",
2604 target_pid_to_str (ptid_of (thread)));
2605
fa96cb38
PA
2606 linux_resume_one_lwp (child, child->stepping, 0, NULL);
2607 return NULL;
2608 }
2609 }
2610
582511be
PA
2611 child->status_pending_p = 1;
2612 child->status_pending = wstat;
fa96cb38
PA
2613 return child;
2614}
2615
f79b145d
YQ
2616/* Return true if THREAD is doing hardware single step. */
2617
2618static int
2619maybe_hw_step (struct thread_info *thread)
2620{
2621 if (can_hardware_single_step ())
2622 return 1;
2623 else
2624 {
f79b145d
YQ
2625 /* GDBserver must insert reinsert breakpoint for software
2626 single step. */
bec903c9 2627 gdb_assert (has_reinsert_breakpoints (thread));
f79b145d
YQ
2628 return 0;
2629 }
2630}
2631
20ba1ce6
PA
2632/* Resume LWPs that are currently stopped without any pending status
2633 to report, but are resumed from the core's perspective. */
2634
2635static void
2636resume_stopped_resumed_lwps (struct inferior_list_entry *entry)
2637{
2638 struct thread_info *thread = (struct thread_info *) entry;
2639 struct lwp_info *lp = get_thread_lwp (thread);
2640
2641 if (lp->stopped
863d01bd 2642 && !lp->suspended
20ba1ce6 2643 && !lp->status_pending_p
20ba1ce6
PA
2644 && thread->last_status.kind == TARGET_WAITKIND_IGNORE)
2645 {
8901d193
YQ
2646 int step = 0;
2647
2648 if (thread->last_resume_kind == resume_step)
2649 step = maybe_hw_step (thread);
20ba1ce6
PA
2650
2651 if (debug_threads)
2652 debug_printf ("RSRL: resuming stopped-resumed LWP %s at %s: step=%d\n",
2653 target_pid_to_str (ptid_of (thread)),
2654 paddress (lp->stop_pc),
2655 step);
2656
2657 linux_resume_one_lwp (lp, step, GDB_SIGNAL_0, NULL);
2658 }
2659}
2660
fa96cb38
PA
2661/* Wait for an event from child(ren) WAIT_PTID, and return any that
2662 match FILTER_PTID (leaving others pending). The PTIDs can be:
2663 minus_one_ptid, to specify any child; a pid PTID, specifying all
2664 lwps of a thread group; or a PTID representing a single lwp. Store
2665 the stop status through the status pointer WSTAT. OPTIONS is
2666 passed to the waitpid call. Return 0 if no event was found and
2667 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
2668 was found. Return the PID of the stopped child otherwise. */
bd99dc85 2669
0d62e5e8 2670static int
fa96cb38
PA
2671linux_wait_for_event_filtered (ptid_t wait_ptid, ptid_t filter_ptid,
2672 int *wstatp, int options)
0d62e5e8 2673{
d86d4aaf 2674 struct thread_info *event_thread;
d50171e4 2675 struct lwp_info *event_child, *requested_child;
fa96cb38 2676 sigset_t block_mask, prev_mask;
d50171e4 2677
fa96cb38 2678 retry:
d86d4aaf
DE
2679 /* N.B. event_thread points to the thread_info struct that contains
2680 event_child. Keep them in sync. */
2681 event_thread = NULL;
d50171e4
PA
2682 event_child = NULL;
2683 requested_child = NULL;
0d62e5e8 2684
95954743 2685 /* Check for a lwp with a pending status. */
bd99dc85 2686
fa96cb38 2687 if (ptid_equal (filter_ptid, minus_one_ptid) || ptid_is_pid (filter_ptid))
0d62e5e8 2688 {
d86d4aaf 2689 event_thread = (struct thread_info *)
fa96cb38 2690 find_inferior (&all_threads, status_pending_p_callback, &filter_ptid);
d86d4aaf
DE
2691 if (event_thread != NULL)
2692 event_child = get_thread_lwp (event_thread);
2693 if (debug_threads && event_thread)
2694 debug_printf ("Got a pending child %ld\n", lwpid_of (event_thread));
0d62e5e8 2695 }
fa96cb38 2696 else if (!ptid_equal (filter_ptid, null_ptid))
0d62e5e8 2697 {
fa96cb38 2698 requested_child = find_lwp_pid (filter_ptid);
d50171e4 2699
bde24c0a 2700 if (stopping_threads == NOT_STOPPING_THREADS
fa593d66
PA
2701 && requested_child->status_pending_p
2702 && requested_child->collecting_fast_tracepoint)
2703 {
2704 enqueue_one_deferred_signal (requested_child,
2705 &requested_child->status_pending);
2706 requested_child->status_pending_p = 0;
2707 requested_child->status_pending = 0;
2708 linux_resume_one_lwp (requested_child, 0, 0, NULL);
2709 }
2710
2711 if (requested_child->suspended
2712 && requested_child->status_pending_p)
38e08fca
GB
2713 {
2714 internal_error (__FILE__, __LINE__,
2715 "requesting an event out of a"
2716 " suspended child?");
2717 }
fa593d66 2718
d50171e4 2719 if (requested_child->status_pending_p)
d86d4aaf
DE
2720 {
2721 event_child = requested_child;
2722 event_thread = get_lwp_thread (event_child);
2723 }
0d62e5e8 2724 }
611cb4a5 2725
0d62e5e8
DJ
2726 if (event_child != NULL)
2727 {
bd99dc85 2728 if (debug_threads)
87ce2a04 2729 debug_printf ("Got an event from pending child %ld (%04x)\n",
d86d4aaf 2730 lwpid_of (event_thread), event_child->status_pending);
fa96cb38 2731 *wstatp = event_child->status_pending;
bd99dc85
PA
2732 event_child->status_pending_p = 0;
2733 event_child->status_pending = 0;
0bfdf32f 2734 current_thread = event_thread;
d86d4aaf 2735 return lwpid_of (event_thread);
0d62e5e8
DJ
2736 }
2737
fa96cb38
PA
2738 /* But if we don't find a pending event, we'll have to wait.
2739
2740 We only enter this loop if no process has a pending wait status.
2741 Thus any action taken in response to a wait status inside this
2742 loop is responding as soon as we detect the status, not after any
2743 pending events. */
d8301ad1 2744
fa96cb38
PA
2745 /* Make sure SIGCHLD is blocked until the sigsuspend below. Block
2746 all signals while here. */
2747 sigfillset (&block_mask);
2748 sigprocmask (SIG_BLOCK, &block_mask, &prev_mask);
2749
582511be
PA
2750 /* Always pull all events out of the kernel. We'll randomly select
2751 an event LWP out of all that have events, to prevent
2752 starvation. */
fa96cb38 2753 while (event_child == NULL)
0d62e5e8 2754 {
fa96cb38 2755 pid_t ret = 0;
0d62e5e8 2756
fa96cb38
PA
2757 /* Always use -1 and WNOHANG, due to couple of a kernel/ptrace
2758 quirks:
0d62e5e8 2759
fa96cb38
PA
2760 - If the thread group leader exits while other threads in the
2761 thread group still exist, waitpid(TGID, ...) hangs. That
2762 waitpid won't return an exit status until the other threads
2763 in the group are reaped.
611cb4a5 2764
fa96cb38
PA
2765 - When a non-leader thread execs, that thread just vanishes
2766 without reporting an exit (so we'd hang if we waited for it
2767 explicitly in that case). The exec event is reported to
94585166 2768 the TGID pid. */
fa96cb38
PA
2769 errno = 0;
2770 ret = my_waitpid (-1, wstatp, options | WNOHANG);
d8301ad1 2771
fa96cb38
PA
2772 if (debug_threads)
2773 debug_printf ("LWFE: waitpid(-1, ...) returned %d, %s\n",
2774 ret, errno ? strerror (errno) : "ERRNO-OK");
0d62e5e8 2775
fa96cb38 2776 if (ret > 0)
0d62e5e8 2777 {
89be2091 2778 if (debug_threads)
bd99dc85 2779 {
fa96cb38
PA
2780 debug_printf ("LLW: waitpid %ld received %s\n",
2781 (long) ret, status_to_str (*wstatp));
bd99dc85 2782 }
89be2091 2783
582511be
PA
2784 /* Filter all events. IOW, leave all events pending. We'll
2785 randomly select an event LWP out of all that have events
2786 below. */
2787 linux_low_filter_event (ret, *wstatp);
fa96cb38
PA
2788 /* Retry until nothing comes out of waitpid. A single
2789 SIGCHLD can indicate more than one child stopped. */
89be2091
DJ
2790 continue;
2791 }
2792
20ba1ce6
PA
2793 /* Now that we've pulled all events out of the kernel, resume
2794 LWPs that don't have an interesting event to report. */
2795 if (stopping_threads == NOT_STOPPING_THREADS)
2796 for_each_inferior (&all_threads, resume_stopped_resumed_lwps);
2797
2798 /* ... and find an LWP with a status to report to the core, if
2799 any. */
582511be
PA
2800 event_thread = (struct thread_info *)
2801 find_inferior (&all_threads, status_pending_p_callback, &filter_ptid);
2802 if (event_thread != NULL)
2803 {
2804 event_child = get_thread_lwp (event_thread);
2805 *wstatp = event_child->status_pending;
2806 event_child->status_pending_p = 0;
2807 event_child->status_pending = 0;
2808 break;
2809 }
2810
fa96cb38
PA
2811 /* Check for zombie thread group leaders. Those can't be reaped
2812 until all other threads in the thread group are. */
2813 check_zombie_leaders ();
2814
2815 /* If there are no resumed children left in the set of LWPs we
2816 want to wait for, bail. We can't just block in
2817 waitpid/sigsuspend, because lwps might have been left stopped
2818 in trace-stop state, and we'd be stuck forever waiting for
2819 their status to change (which would only happen if we resumed
2820 them). Even if WNOHANG is set, this return code is preferred
2821 over 0 (below), as it is more detailed. */
2822 if ((find_inferior (&all_threads,
2823 not_stopped_callback,
2824 &wait_ptid) == NULL))
a6dbe5df 2825 {
fa96cb38
PA
2826 if (debug_threads)
2827 debug_printf ("LLW: exit (no unwaited-for LWP)\n");
2828 sigprocmask (SIG_SETMASK, &prev_mask, NULL);
2829 return -1;
a6dbe5df
PA
2830 }
2831
fa96cb38
PA
2832 /* No interesting event to report to the caller. */
2833 if ((options & WNOHANG))
24a09b5f 2834 {
fa96cb38
PA
2835 if (debug_threads)
2836 debug_printf ("WNOHANG set, no event found\n");
2837
2838 sigprocmask (SIG_SETMASK, &prev_mask, NULL);
2839 return 0;
24a09b5f
DJ
2840 }
2841
fa96cb38
PA
2842 /* Block until we get an event reported with SIGCHLD. */
2843 if (debug_threads)
2844 debug_printf ("sigsuspend'ing\n");
d50171e4 2845
fa96cb38
PA
2846 sigsuspend (&prev_mask);
2847 sigprocmask (SIG_SETMASK, &prev_mask, NULL);
2848 goto retry;
2849 }
d50171e4 2850
fa96cb38 2851 sigprocmask (SIG_SETMASK, &prev_mask, NULL);
d50171e4 2852
0bfdf32f 2853 current_thread = event_thread;
d50171e4 2854
fa96cb38
PA
2855 return lwpid_of (event_thread);
2856}
2857
2858/* Wait for an event from child(ren) PTID. PTIDs can be:
2859 minus_one_ptid, to specify any child; a pid PTID, specifying all
2860 lwps of a thread group; or a PTID representing a single lwp. Store
2861 the stop status through the status pointer WSTAT. OPTIONS is
2862 passed to the waitpid call. Return 0 if no event was found and
2863 OPTIONS contains WNOHANG. Return -1 if no unwaited-for children
2864 was found. Return the PID of the stopped child otherwise. */
2865
2866static int
2867linux_wait_for_event (ptid_t ptid, int *wstatp, int options)
2868{
2869 return linux_wait_for_event_filtered (ptid, ptid, wstatp, options);
611cb4a5
DJ
2870}
2871
6bf5e0ba
PA
2872/* Count the LWP's that have had events. */
2873
2874static int
2875count_events_callback (struct inferior_list_entry *entry, void *data)
2876{
d86d4aaf 2877 struct thread_info *thread = (struct thread_info *) entry;
8bf3b159 2878 struct lwp_info *lp = get_thread_lwp (thread);
9a3c8263 2879 int *count = (int *) data;
6bf5e0ba
PA
2880
2881 gdb_assert (count != NULL);
2882
582511be 2883 /* Count only resumed LWPs that have an event pending. */
8336d594 2884 if (thread->last_status.kind == TARGET_WAITKIND_IGNORE
8bf3b159 2885 && lp->status_pending_p)
6bf5e0ba
PA
2886 (*count)++;
2887
2888 return 0;
2889}
2890
2891/* Select the LWP (if any) that is currently being single-stepped. */
2892
2893static int
2894select_singlestep_lwp_callback (struct inferior_list_entry *entry, void *data)
2895{
d86d4aaf
DE
2896 struct thread_info *thread = (struct thread_info *) entry;
2897 struct lwp_info *lp = get_thread_lwp (thread);
6bf5e0ba 2898
8336d594
PA
2899 if (thread->last_status.kind == TARGET_WAITKIND_IGNORE
2900 && thread->last_resume_kind == resume_step
6bf5e0ba
PA
2901 && lp->status_pending_p)
2902 return 1;
2903 else
2904 return 0;
2905}
2906
b90fc188 2907/* Select the Nth LWP that has had an event. */
6bf5e0ba
PA
2908
2909static int
2910select_event_lwp_callback (struct inferior_list_entry *entry, void *data)
2911{
d86d4aaf 2912 struct thread_info *thread = (struct thread_info *) entry;
8bf3b159 2913 struct lwp_info *lp = get_thread_lwp (thread);
9a3c8263 2914 int *selector = (int *) data;
6bf5e0ba
PA
2915
2916 gdb_assert (selector != NULL);
2917
582511be 2918 /* Select only resumed LWPs that have an event pending. */
91baf43f 2919 if (thread->last_status.kind == TARGET_WAITKIND_IGNORE
8bf3b159 2920 && lp->status_pending_p)
6bf5e0ba
PA
2921 if ((*selector)-- == 0)
2922 return 1;
2923
2924 return 0;
2925}
2926
6bf5e0ba
PA
2927/* Select one LWP out of those that have events pending. */
2928
2929static void
2930select_event_lwp (struct lwp_info **orig_lp)
2931{
2932 int num_events = 0;
2933 int random_selector;
582511be
PA
2934 struct thread_info *event_thread = NULL;
2935
2936 /* In all-stop, give preference to the LWP that is being
2937 single-stepped. There will be at most one, and it's the LWP that
2938 the core is most interested in. If we didn't do this, then we'd
2939 have to handle pending step SIGTRAPs somehow in case the core
2940 later continues the previously-stepped thread, otherwise we'd
2941 report the pending SIGTRAP, and the core, not having stepped the
2942 thread, wouldn't understand what the trap was for, and therefore
2943 would report it to the user as a random signal. */
2944 if (!non_stop)
6bf5e0ba 2945 {
582511be
PA
2946 event_thread
2947 = (struct thread_info *) find_inferior (&all_threads,
2948 select_singlestep_lwp_callback,
2949 NULL);
2950 if (event_thread != NULL)
2951 {
2952 if (debug_threads)
2953 debug_printf ("SEL: Select single-step %s\n",
2954 target_pid_to_str (ptid_of (event_thread)));
2955 }
6bf5e0ba 2956 }
582511be 2957 if (event_thread == NULL)
6bf5e0ba
PA
2958 {
2959 /* No single-stepping LWP. Select one at random, out of those
b90fc188 2960 which have had events. */
6bf5e0ba 2961
b90fc188 2962 /* First see how many events we have. */
d86d4aaf 2963 find_inferior (&all_threads, count_events_callback, &num_events);
8bf3b159 2964 gdb_assert (num_events > 0);
6bf5e0ba 2965
b90fc188
PA
2966 /* Now randomly pick a LWP out of those that have had
2967 events. */
6bf5e0ba
PA
2968 random_selector = (int)
2969 ((num_events * (double) rand ()) / (RAND_MAX + 1.0));
2970
2971 if (debug_threads && num_events > 1)
87ce2a04
DE
2972 debug_printf ("SEL: Found %d SIGTRAP events, selecting #%d\n",
2973 num_events, random_selector);
6bf5e0ba 2974
d86d4aaf
DE
2975 event_thread
2976 = (struct thread_info *) find_inferior (&all_threads,
2977 select_event_lwp_callback,
2978 &random_selector);
6bf5e0ba
PA
2979 }
2980
d86d4aaf 2981 if (event_thread != NULL)
6bf5e0ba 2982 {
d86d4aaf
DE
2983 struct lwp_info *event_lp = get_thread_lwp (event_thread);
2984
6bf5e0ba
PA
2985 /* Switch the event LWP. */
2986 *orig_lp = event_lp;
2987 }
2988}
2989
7984d532
PA
2990/* Decrement the suspend count of an LWP. */
2991
2992static int
2993unsuspend_one_lwp (struct inferior_list_entry *entry, void *except)
2994{
d86d4aaf
DE
2995 struct thread_info *thread = (struct thread_info *) entry;
2996 struct lwp_info *lwp = get_thread_lwp (thread);
7984d532
PA
2997
2998 /* Ignore EXCEPT. */
2999 if (lwp == except)
3000 return 0;
3001
863d01bd 3002 lwp_suspended_decr (lwp);
7984d532
PA
3003 return 0;
3004}
3005
3006/* Decrement the suspend count of all LWPs, except EXCEPT, if non
3007 NULL. */
3008
3009static void
3010unsuspend_all_lwps (struct lwp_info *except)
3011{
d86d4aaf 3012 find_inferior (&all_threads, unsuspend_one_lwp, except);
7984d532
PA
3013}
3014
fa593d66
PA
3015static void move_out_of_jump_pad_callback (struct inferior_list_entry *entry);
3016static int stuck_in_jump_pad_callback (struct inferior_list_entry *entry,
3017 void *data);
3018static int lwp_running (struct inferior_list_entry *entry, void *data);
3019static ptid_t linux_wait_1 (ptid_t ptid,
3020 struct target_waitstatus *ourstatus,
3021 int target_options);
3022
3023/* Stabilize threads (move out of jump pads).
3024
3025 If a thread is midway collecting a fast tracepoint, we need to
3026 finish the collection and move it out of the jump pad before
3027 reporting the signal.
3028
3029 This avoids recursion while collecting (when a signal arrives
3030 midway, and the signal handler itself collects), which would trash
3031 the trace buffer. In case the user set a breakpoint in a signal
3032 handler, this avoids the backtrace showing the jump pad, etc..
3033 Most importantly, there are certain things we can't do safely if
3034 threads are stopped in a jump pad (or in its callee's). For
3035 example:
3036
3037 - starting a new trace run. A thread still collecting the
3038 previous run, could trash the trace buffer when resumed. The trace
3039 buffer control structures would have been reset but the thread had
3040 no way to tell. The thread could even midway memcpy'ing to the
3041 buffer, which would mean that when resumed, it would clobber the
3042 trace buffer that had been set for a new run.
3043
3044 - we can't rewrite/reuse the jump pads for new tracepoints
3045 safely. Say you do tstart while a thread is stopped midway while
3046 collecting. When the thread is later resumed, it finishes the
3047 collection, and returns to the jump pad, to execute the original
3048 instruction that was under the tracepoint jump at the time the
3049 older run had been started. If the jump pad had been rewritten
3050 since for something else in the new run, the thread would now
3051 execute the wrong / random instructions. */
3052
3053static void
3054linux_stabilize_threads (void)
3055{
0bfdf32f 3056 struct thread_info *saved_thread;
d86d4aaf 3057 struct thread_info *thread_stuck;
fa593d66 3058
d86d4aaf
DE
3059 thread_stuck
3060 = (struct thread_info *) find_inferior (&all_threads,
3061 stuck_in_jump_pad_callback,
3062 NULL);
3063 if (thread_stuck != NULL)
fa593d66 3064 {
b4d51a55 3065 if (debug_threads)
87ce2a04 3066 debug_printf ("can't stabilize, LWP %ld is stuck in jump pad\n",
d86d4aaf 3067 lwpid_of (thread_stuck));
fa593d66
PA
3068 return;
3069 }
3070
0bfdf32f 3071 saved_thread = current_thread;
fa593d66
PA
3072
3073 stabilizing_threads = 1;
3074
3075 /* Kick 'em all. */
d86d4aaf 3076 for_each_inferior (&all_threads, move_out_of_jump_pad_callback);
fa593d66
PA
3077
3078 /* Loop until all are stopped out of the jump pads. */
d86d4aaf 3079 while (find_inferior (&all_threads, lwp_running, NULL) != NULL)
fa593d66
PA
3080 {
3081 struct target_waitstatus ourstatus;
3082 struct lwp_info *lwp;
fa593d66
PA
3083 int wstat;
3084
3085 /* Note that we go through the full wait even loop. While
3086 moving threads out of jump pad, we need to be able to step
3087 over internal breakpoints and such. */
32fcada3 3088 linux_wait_1 (minus_one_ptid, &ourstatus, 0);
fa593d66
PA
3089
3090 if (ourstatus.kind == TARGET_WAITKIND_STOPPED)
3091 {
0bfdf32f 3092 lwp = get_thread_lwp (current_thread);
fa593d66
PA
3093
3094 /* Lock it. */
863d01bd 3095 lwp_suspended_inc (lwp);
fa593d66 3096
a493e3e2 3097 if (ourstatus.value.sig != GDB_SIGNAL_0
0bfdf32f 3098 || current_thread->last_resume_kind == resume_stop)
fa593d66 3099 {
2ea28649 3100 wstat = W_STOPCODE (gdb_signal_to_host (ourstatus.value.sig));
fa593d66
PA
3101 enqueue_one_deferred_signal (lwp, &wstat);
3102 }
3103 }
3104 }
3105
fcdad592 3106 unsuspend_all_lwps (NULL);
fa593d66
PA
3107
3108 stabilizing_threads = 0;
3109
0bfdf32f 3110 current_thread = saved_thread;
fa593d66 3111
b4d51a55 3112 if (debug_threads)
fa593d66 3113 {
d86d4aaf
DE
3114 thread_stuck
3115 = (struct thread_info *) find_inferior (&all_threads,
3116 stuck_in_jump_pad_callback,
3117 NULL);
3118 if (thread_stuck != NULL)
87ce2a04 3119 debug_printf ("couldn't stabilize, LWP %ld got stuck in jump pad\n",
d86d4aaf 3120 lwpid_of (thread_stuck));
fa593d66
PA
3121 }
3122}
3123
582511be
PA
3124/* Convenience function that is called when the kernel reports an
3125 event that is not passed out to GDB. */
3126
3127static ptid_t
3128ignore_event (struct target_waitstatus *ourstatus)
3129{
3130 /* If we got an event, there may still be others, as a single
3131 SIGCHLD can indicate more than one child stopped. This forces
3132 another target_wait call. */
3133 async_file_mark ();
3134
3135 ourstatus->kind = TARGET_WAITKIND_IGNORE;
3136 return null_ptid;
3137}
3138
65706a29
PA
3139/* Convenience function that is called when the kernel reports an exit
3140 event. This decides whether to report the event to GDB as a
3141 process exit event, a thread exit event, or to suppress the
3142 event. */
3143
3144static ptid_t
3145filter_exit_event (struct lwp_info *event_child,
3146 struct target_waitstatus *ourstatus)
3147{
3148 struct thread_info *thread = get_lwp_thread (event_child);
3149 ptid_t ptid = ptid_of (thread);
3150
3151 if (!last_thread_of_process_p (pid_of (thread)))
3152 {
3153 if (report_thread_events)
3154 ourstatus->kind = TARGET_WAITKIND_THREAD_EXITED;
3155 else
3156 ourstatus->kind = TARGET_WAITKIND_IGNORE;
3157
3158 delete_lwp (event_child);
3159 }
3160 return ptid;
3161}
3162
82075af2
JS
3163/* Returns 1 if GDB is interested in any event_child syscalls. */
3164
3165static int
3166gdb_catching_syscalls_p (struct lwp_info *event_child)
3167{
3168 struct thread_info *thread = get_lwp_thread (event_child);
3169 struct process_info *proc = get_thread_process (thread);
3170
3171 return !VEC_empty (int, proc->syscalls_to_catch);
3172}
3173
3174/* Returns 1 if GDB is interested in the event_child syscall.
3175 Only to be called when stopped reason is SYSCALL_SIGTRAP. */
3176
3177static int
3178gdb_catch_this_syscall_p (struct lwp_info *event_child)
3179{
3180 int i, iter;
4cc32bec 3181 int sysno;
82075af2
JS
3182 struct thread_info *thread = get_lwp_thread (event_child);
3183 struct process_info *proc = get_thread_process (thread);
3184
3185 if (VEC_empty (int, proc->syscalls_to_catch))
3186 return 0;
3187
3188 if (VEC_index (int, proc->syscalls_to_catch, 0) == ANY_SYSCALL)
3189 return 1;
3190
4cc32bec 3191 get_syscall_trapinfo (event_child, &sysno);
82075af2
JS
3192 for (i = 0;
3193 VEC_iterate (int, proc->syscalls_to_catch, i, iter);
3194 i++)
3195 if (iter == sysno)
3196 return 1;
3197
3198 return 0;
3199}
3200
0d62e5e8 3201/* Wait for process, returns status. */
da6d8c04 3202
95954743
PA
3203static ptid_t
3204linux_wait_1 (ptid_t ptid,
3205 struct target_waitstatus *ourstatus, int target_options)
da6d8c04 3206{
e5f1222d 3207 int w;
fc7238bb 3208 struct lwp_info *event_child;
bd99dc85 3209 int options;
bd99dc85 3210 int pid;
6bf5e0ba
PA
3211 int step_over_finished;
3212 int bp_explains_trap;
3213 int maybe_internal_trap;
3214 int report_to_gdb;
219f2f23 3215 int trace_event;
c2d6af84 3216 int in_step_range;
f2faf941 3217 int any_resumed;
bd99dc85 3218
87ce2a04
DE
3219 if (debug_threads)
3220 {
3221 debug_enter ();
3222 debug_printf ("linux_wait_1: [%s]\n", target_pid_to_str (ptid));
3223 }
3224
bd99dc85
PA
3225 /* Translate generic target options into linux options. */
3226 options = __WALL;
3227 if (target_options & TARGET_WNOHANG)
3228 options |= WNOHANG;
0d62e5e8 3229
fa593d66
PA
3230 bp_explains_trap = 0;
3231 trace_event = 0;
c2d6af84 3232 in_step_range = 0;
bd99dc85
PA
3233 ourstatus->kind = TARGET_WAITKIND_IGNORE;
3234
f2faf941
PA
3235 /* Find a resumed LWP, if any. */
3236 if (find_inferior (&all_threads,
3237 status_pending_p_callback,
3238 &minus_one_ptid) != NULL)
3239 any_resumed = 1;
3240 else if ((find_inferior (&all_threads,
3241 not_stopped_callback,
3242 &minus_one_ptid) != NULL))
3243 any_resumed = 1;
3244 else
3245 any_resumed = 0;
3246
6bf5e0ba
PA
3247 if (ptid_equal (step_over_bkpt, null_ptid))
3248 pid = linux_wait_for_event (ptid, &w, options);
3249 else
3250 {
3251 if (debug_threads)
87ce2a04
DE
3252 debug_printf ("step_over_bkpt set [%s], doing a blocking wait\n",
3253 target_pid_to_str (step_over_bkpt));
6bf5e0ba
PA
3254 pid = linux_wait_for_event (step_over_bkpt, &w, options & ~WNOHANG);
3255 }
3256
f2faf941 3257 if (pid == 0 || (pid == -1 && !any_resumed))
87ce2a04 3258 {
fa96cb38
PA
3259 gdb_assert (target_options & TARGET_WNOHANG);
3260
87ce2a04
DE
3261 if (debug_threads)
3262 {
fa96cb38
PA
3263 debug_printf ("linux_wait_1 ret = null_ptid, "
3264 "TARGET_WAITKIND_IGNORE\n");
87ce2a04
DE
3265 debug_exit ();
3266 }
fa96cb38
PA
3267
3268 ourstatus->kind = TARGET_WAITKIND_IGNORE;
87ce2a04
DE
3269 return null_ptid;
3270 }
fa96cb38
PA
3271 else if (pid == -1)
3272 {
3273 if (debug_threads)
3274 {
3275 debug_printf ("linux_wait_1 ret = null_ptid, "
3276 "TARGET_WAITKIND_NO_RESUMED\n");
3277 debug_exit ();
3278 }
bd99dc85 3279
fa96cb38
PA
3280 ourstatus->kind = TARGET_WAITKIND_NO_RESUMED;
3281 return null_ptid;
3282 }
0d62e5e8 3283
0bfdf32f 3284 event_child = get_thread_lwp (current_thread);
0d62e5e8 3285
fa96cb38
PA
3286 /* linux_wait_for_event only returns an exit status for the last
3287 child of a process. Report it. */
3288 if (WIFEXITED (w) || WIFSIGNALED (w))
da6d8c04 3289 {
fa96cb38 3290 if (WIFEXITED (w))
0d62e5e8 3291 {
fa96cb38
PA
3292 ourstatus->kind = TARGET_WAITKIND_EXITED;
3293 ourstatus->value.integer = WEXITSTATUS (w);
bd99dc85 3294
fa96cb38 3295 if (debug_threads)
bd99dc85 3296 {
fa96cb38
PA
3297 debug_printf ("linux_wait_1 ret = %s, exited with "
3298 "retcode %d\n",
0bfdf32f 3299 target_pid_to_str (ptid_of (current_thread)),
fa96cb38
PA
3300 WEXITSTATUS (w));
3301 debug_exit ();
bd99dc85 3302 }
fa96cb38
PA
3303 }
3304 else
3305 {
3306 ourstatus->kind = TARGET_WAITKIND_SIGNALLED;
3307 ourstatus->value.sig = gdb_signal_from_host (WTERMSIG (w));
5b1c542e 3308
fa96cb38
PA
3309 if (debug_threads)
3310 {
3311 debug_printf ("linux_wait_1 ret = %s, terminated with "
3312 "signal %d\n",
0bfdf32f 3313 target_pid_to_str (ptid_of (current_thread)),
fa96cb38
PA
3314 WTERMSIG (w));
3315 debug_exit ();
3316 }
0d62e5e8 3317 }
fa96cb38 3318
65706a29
PA
3319 if (ourstatus->kind == TARGET_WAITKIND_EXITED)
3320 return filter_exit_event (event_child, ourstatus);
3321
0bfdf32f 3322 return ptid_of (current_thread);
da6d8c04
DJ
3323 }
3324
2d97cd35
AT
3325 /* If step-over executes a breakpoint instruction, in the case of a
3326 hardware single step it means a gdb/gdbserver breakpoint had been
3327 planted on top of a permanent breakpoint, in the case of a software
3328 single step it may just mean that gdbserver hit the reinsert breakpoint.
e7ad2f14 3329 The PC has been adjusted by save_stop_reason to point at
2d97cd35
AT
3330 the breakpoint address.
3331 So in the case of the hardware single step advance the PC manually
3332 past the breakpoint and in the case of software single step advance only
3333 if it's not the reinsert_breakpoint we are hitting.
3334 This avoids that a program would keep trapping a permanent breakpoint
3335 forever. */
8090aef2 3336 if (!ptid_equal (step_over_bkpt, null_ptid)
2d97cd35
AT
3337 && event_child->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT
3338 && (event_child->stepping
3339 || !reinsert_breakpoint_inserted_here (event_child->stop_pc)))
8090aef2 3340 {
dd373349
AT
3341 int increment_pc = 0;
3342 int breakpoint_kind = 0;
3343 CORE_ADDR stop_pc = event_child->stop_pc;
3344
769ef81f
AT
3345 breakpoint_kind =
3346 the_target->breakpoint_kind_from_current_state (&stop_pc);
dd373349 3347 the_target->sw_breakpoint_from_kind (breakpoint_kind, &increment_pc);
8090aef2
PA
3348
3349 if (debug_threads)
3350 {
3351 debug_printf ("step-over for %s executed software breakpoint\n",
3352 target_pid_to_str (ptid_of (current_thread)));
3353 }
3354
3355 if (increment_pc != 0)
3356 {
3357 struct regcache *regcache
3358 = get_thread_regcache (current_thread, 1);
3359
3360 event_child->stop_pc += increment_pc;
3361 (*the_low_target.set_pc) (regcache, event_child->stop_pc);
3362
3363 if (!(*the_low_target.breakpoint_at) (event_child->stop_pc))
15c66dd6 3364 event_child->stop_reason = TARGET_STOPPED_BY_NO_REASON;
8090aef2
PA
3365 }
3366 }
3367
6bf5e0ba
PA
3368 /* If this event was not handled before, and is not a SIGTRAP, we
3369 report it. SIGILL and SIGSEGV are also treated as traps in case
3370 a breakpoint is inserted at the current PC. If this target does
3371 not support internal breakpoints at all, we also report the
3372 SIGTRAP without further processing; it's of no concern to us. */
3373 maybe_internal_trap
3374 = (supports_breakpoints ()
3375 && (WSTOPSIG (w) == SIGTRAP
3376 || ((WSTOPSIG (w) == SIGILL
3377 || WSTOPSIG (w) == SIGSEGV)
3378 && (*the_low_target.breakpoint_at) (event_child->stop_pc))));
3379
3380 if (maybe_internal_trap)
3381 {
3382 /* Handle anything that requires bookkeeping before deciding to
3383 report the event or continue waiting. */
3384
3385 /* First check if we can explain the SIGTRAP with an internal
3386 breakpoint, or if we should possibly report the event to GDB.
3387 Do this before anything that may remove or insert a
3388 breakpoint. */
3389 bp_explains_trap = breakpoint_inserted_here (event_child->stop_pc);
3390
3391 /* We have a SIGTRAP, possibly a step-over dance has just
3392 finished. If so, tweak the state machine accordingly,
3393 reinsert breakpoints and delete any reinsert (software
3394 single-step) breakpoints. */
3395 step_over_finished = finish_step_over (event_child);
3396
3397 /* Now invoke the callbacks of any internal breakpoints there. */
3398 check_breakpoints (event_child->stop_pc);
3399
219f2f23
PA
3400 /* Handle tracepoint data collecting. This may overflow the
3401 trace buffer, and cause a tracing stop, removing
3402 breakpoints. */
3403 trace_event = handle_tracepoints (event_child);
3404
6bf5e0ba
PA
3405 if (bp_explains_trap)
3406 {
6bf5e0ba 3407 if (debug_threads)
87ce2a04 3408 debug_printf ("Hit a gdbserver breakpoint.\n");
6bf5e0ba
PA
3409 }
3410 }
3411 else
3412 {
3413 /* We have some other signal, possibly a step-over dance was in
3414 progress, and it should be cancelled too. */
3415 step_over_finished = finish_step_over (event_child);
fa593d66
PA
3416 }
3417
3418 /* We have all the data we need. Either report the event to GDB, or
3419 resume threads and keep waiting for more. */
3420
3421 /* If we're collecting a fast tracepoint, finish the collection and
3422 move out of the jump pad before delivering a signal. See
3423 linux_stabilize_threads. */
3424
3425 if (WIFSTOPPED (w)
3426 && WSTOPSIG (w) != SIGTRAP
3427 && supports_fast_tracepoints ()
58b4daa5 3428 && agent_loaded_p ())
fa593d66
PA
3429 {
3430 if (debug_threads)
87ce2a04
DE
3431 debug_printf ("Got signal %d for LWP %ld. Check if we need "
3432 "to defer or adjust it.\n",
0bfdf32f 3433 WSTOPSIG (w), lwpid_of (current_thread));
fa593d66
PA
3434
3435 /* Allow debugging the jump pad itself. */
0bfdf32f 3436 if (current_thread->last_resume_kind != resume_step
fa593d66
PA
3437 && maybe_move_out_of_jump_pad (event_child, &w))
3438 {
3439 enqueue_one_deferred_signal (event_child, &w);
3440
3441 if (debug_threads)
87ce2a04 3442 debug_printf ("Signal %d for LWP %ld deferred (in jump pad)\n",
0bfdf32f 3443 WSTOPSIG (w), lwpid_of (current_thread));
fa593d66
PA
3444
3445 linux_resume_one_lwp (event_child, 0, 0, NULL);
582511be
PA
3446
3447 return ignore_event (ourstatus);
fa593d66
PA
3448 }
3449 }
219f2f23 3450
fa593d66
PA
3451 if (event_child->collecting_fast_tracepoint)
3452 {
3453 if (debug_threads)
87ce2a04
DE
3454 debug_printf ("LWP %ld was trying to move out of the jump pad (%d). "
3455 "Check if we're already there.\n",
0bfdf32f 3456 lwpid_of (current_thread),
87ce2a04 3457 event_child->collecting_fast_tracepoint);
fa593d66
PA
3458
3459 trace_event = 1;
3460
3461 event_child->collecting_fast_tracepoint
3462 = linux_fast_tracepoint_collecting (event_child, NULL);
3463
3464 if (event_child->collecting_fast_tracepoint != 1)
3465 {
3466 /* No longer need this breakpoint. */
3467 if (event_child->exit_jump_pad_bkpt != NULL)
3468 {
3469 if (debug_threads)
87ce2a04
DE
3470 debug_printf ("No longer need exit-jump-pad bkpt; removing it."
3471 "stopping all threads momentarily.\n");
fa593d66
PA
3472
3473 /* Other running threads could hit this breakpoint.
3474 We don't handle moribund locations like GDB does,
3475 instead we always pause all threads when removing
3476 breakpoints, so that any step-over or
3477 decr_pc_after_break adjustment is always taken
3478 care of while the breakpoint is still
3479 inserted. */
3480 stop_all_lwps (1, event_child);
fa593d66
PA
3481
3482 delete_breakpoint (event_child->exit_jump_pad_bkpt);
3483 event_child->exit_jump_pad_bkpt = NULL;
3484
3485 unstop_all_lwps (1, event_child);
3486
3487 gdb_assert (event_child->suspended >= 0);
3488 }
3489 }
3490
3491 if (event_child->collecting_fast_tracepoint == 0)
3492 {
3493 if (debug_threads)
87ce2a04
DE
3494 debug_printf ("fast tracepoint finished "
3495 "collecting successfully.\n");
fa593d66
PA
3496
3497 /* We may have a deferred signal to report. */
3498 if (dequeue_one_deferred_signal (event_child, &w))
3499 {
3500 if (debug_threads)
87ce2a04 3501 debug_printf ("dequeued one signal.\n");
fa593d66 3502 }
3c11dd79 3503 else
fa593d66 3504 {
3c11dd79 3505 if (debug_threads)
87ce2a04 3506 debug_printf ("no deferred signals.\n");
fa593d66
PA
3507
3508 if (stabilizing_threads)
3509 {
3510 ourstatus->kind = TARGET_WAITKIND_STOPPED;
a493e3e2 3511 ourstatus->value.sig = GDB_SIGNAL_0;
87ce2a04
DE
3512
3513 if (debug_threads)
3514 {
3515 debug_printf ("linux_wait_1 ret = %s, stopped "
3516 "while stabilizing threads\n",
0bfdf32f 3517 target_pid_to_str (ptid_of (current_thread)));
87ce2a04
DE
3518 debug_exit ();
3519 }
3520
0bfdf32f 3521 return ptid_of (current_thread);
fa593d66
PA
3522 }
3523 }
3524 }
6bf5e0ba
PA
3525 }
3526
e471f25b
PA
3527 /* Check whether GDB would be interested in this event. */
3528
82075af2
JS
3529 /* Check if GDB is interested in this syscall. */
3530 if (WIFSTOPPED (w)
3531 && WSTOPSIG (w) == SYSCALL_SIGTRAP
3532 && !gdb_catch_this_syscall_p (event_child))
3533 {
3534 if (debug_threads)
3535 {
3536 debug_printf ("Ignored syscall for LWP %ld.\n",
3537 lwpid_of (current_thread));
3538 }
3539
3540 linux_resume_one_lwp (event_child, event_child->stepping,
3541 0, NULL);
3542 return ignore_event (ourstatus);
3543 }
3544
e471f25b
PA
3545 /* If GDB is not interested in this signal, don't stop other
3546 threads, and don't report it to GDB. Just resume the inferior
3547 right away. We do this for threading-related signals as well as
3548 any that GDB specifically requested we ignore. But never ignore
3549 SIGSTOP if we sent it ourselves, and do not ignore signals when
3550 stepping - they may require special handling to skip the signal
c9587f88
AT
3551 handler. Also never ignore signals that could be caused by a
3552 breakpoint. */
e471f25b 3553 if (WIFSTOPPED (w)
0bfdf32f 3554 && current_thread->last_resume_kind != resume_step
e471f25b 3555 && (
1a981360 3556#if defined (USE_THREAD_DB) && !defined (__ANDROID__)
fe978cb0 3557 (current_process ()->priv->thread_db != NULL
e471f25b
PA
3558 && (WSTOPSIG (w) == __SIGRTMIN
3559 || WSTOPSIG (w) == __SIGRTMIN + 1))
3560 ||
3561#endif
2ea28649 3562 (pass_signals[gdb_signal_from_host (WSTOPSIG (w))]
e471f25b 3563 && !(WSTOPSIG (w) == SIGSTOP
c9587f88
AT
3564 && current_thread->last_resume_kind == resume_stop)
3565 && !linux_wstatus_maybe_breakpoint (w))))
e471f25b
PA
3566 {
3567 siginfo_t info, *info_p;
3568
3569 if (debug_threads)
87ce2a04 3570 debug_printf ("Ignored signal %d for LWP %ld.\n",
0bfdf32f 3571 WSTOPSIG (w), lwpid_of (current_thread));
e471f25b 3572
0bfdf32f 3573 if (ptrace (PTRACE_GETSIGINFO, lwpid_of (current_thread),
b8e1b30e 3574 (PTRACE_TYPE_ARG3) 0, &info) == 0)
e471f25b
PA
3575 info_p = &info;
3576 else
3577 info_p = NULL;
863d01bd
PA
3578
3579 if (step_over_finished)
3580 {
3581 /* We cancelled this thread's step-over above. We still
3582 need to unsuspend all other LWPs, and set them back
3583 running again while the signal handler runs. */
3584 unsuspend_all_lwps (event_child);
3585
3586 /* Enqueue the pending signal info so that proceed_all_lwps
3587 doesn't lose it. */
3588 enqueue_pending_signal (event_child, WSTOPSIG (w), info_p);
3589
3590 proceed_all_lwps ();
3591 }
3592 else
3593 {
3594 linux_resume_one_lwp (event_child, event_child->stepping,
3595 WSTOPSIG (w), info_p);
3596 }
582511be 3597 return ignore_event (ourstatus);
e471f25b
PA
3598 }
3599
c2d6af84
PA
3600 /* Note that all addresses are always "out of the step range" when
3601 there's no range to begin with. */
3602 in_step_range = lwp_in_step_range (event_child);
3603
3604 /* If GDB wanted this thread to single step, and the thread is out
3605 of the step range, we always want to report the SIGTRAP, and let
3606 GDB handle it. Watchpoints should always be reported. So should
3607 signals we can't explain. A SIGTRAP we can't explain could be a
3608 GDB breakpoint --- we may or not support Z0 breakpoints. If we
3609 do, we're be able to handle GDB breakpoints on top of internal
3610 breakpoints, by handling the internal breakpoint and still
3611 reporting the event to GDB. If we don't, we're out of luck, GDB
863d01bd
PA
3612 won't see the breakpoint hit. If we see a single-step event but
3613 the thread should be continuing, don't pass the trap to gdb.
3614 That indicates that we had previously finished a single-step but
3615 left the single-step pending -- see
3616 complete_ongoing_step_over. */
6bf5e0ba 3617 report_to_gdb = (!maybe_internal_trap
0bfdf32f 3618 || (current_thread->last_resume_kind == resume_step
c2d6af84 3619 && !in_step_range)
15c66dd6 3620 || event_child->stop_reason == TARGET_STOPPED_BY_WATCHPOINT
863d01bd
PA
3621 || (!in_step_range
3622 && !bp_explains_trap
3623 && !trace_event
3624 && !step_over_finished
3625 && !(current_thread->last_resume_kind == resume_continue
3626 && event_child->stop_reason == TARGET_STOPPED_BY_SINGLE_STEP))
9f3a5c85 3627 || (gdb_breakpoint_here (event_child->stop_pc)
d3ce09f5 3628 && gdb_condition_true_at_breakpoint (event_child->stop_pc)
de0d863e 3629 && gdb_no_commands_at_breakpoint (event_child->stop_pc))
00db26fa 3630 || event_child->waitstatus.kind != TARGET_WAITKIND_IGNORE);
d3ce09f5
SS
3631
3632 run_breakpoint_commands (event_child->stop_pc);
6bf5e0ba
PA
3633
3634 /* We found no reason GDB would want us to stop. We either hit one
3635 of our own breakpoints, or finished an internal step GDB
3636 shouldn't know about. */
3637 if (!report_to_gdb)
3638 {
3639 if (debug_threads)
3640 {
3641 if (bp_explains_trap)
87ce2a04 3642 debug_printf ("Hit a gdbserver breakpoint.\n");
6bf5e0ba 3643 if (step_over_finished)
87ce2a04 3644 debug_printf ("Step-over finished.\n");
219f2f23 3645 if (trace_event)
87ce2a04 3646 debug_printf ("Tracepoint event.\n");
c2d6af84 3647 if (lwp_in_step_range (event_child))
87ce2a04
DE
3648 debug_printf ("Range stepping pc 0x%s [0x%s, 0x%s).\n",
3649 paddress (event_child->stop_pc),
3650 paddress (event_child->step_range_start),
3651 paddress (event_child->step_range_end));
6bf5e0ba
PA
3652 }
3653
3654 /* We're not reporting this breakpoint to GDB, so apply the
3655 decr_pc_after_break adjustment to the inferior's regcache
3656 ourselves. */
3657
3658 if (the_low_target.set_pc != NULL)
3659 {
3660 struct regcache *regcache
0bfdf32f 3661 = get_thread_regcache (current_thread, 1);
6bf5e0ba
PA
3662 (*the_low_target.set_pc) (regcache, event_child->stop_pc);
3663 }
3664
7984d532
PA
3665 /* We may have finished stepping over a breakpoint. If so,
3666 we've stopped and suspended all LWPs momentarily except the
3667 stepping one. This is where we resume them all again. We're
3668 going to keep waiting, so use proceed, which handles stepping
3669 over the next breakpoint. */
6bf5e0ba 3670 if (debug_threads)
87ce2a04 3671 debug_printf ("proceeding all threads.\n");
7984d532
PA
3672
3673 if (step_over_finished)
3674 unsuspend_all_lwps (event_child);
3675
6bf5e0ba 3676 proceed_all_lwps ();
582511be 3677 return ignore_event (ourstatus);
6bf5e0ba
PA
3678 }
3679
3680 if (debug_threads)
3681 {
00db26fa 3682 if (event_child->waitstatus.kind != TARGET_WAITKIND_IGNORE)
ad071a30
PA
3683 {
3684 char *str;
3685
3686 str = target_waitstatus_to_string (&event_child->waitstatus);
3687 debug_printf ("LWP %ld: extended event with waitstatus %s\n",
3688 lwpid_of (get_lwp_thread (event_child)), str);
3689 xfree (str);
3690 }
0bfdf32f 3691 if (current_thread->last_resume_kind == resume_step)
c2d6af84
PA
3692 {
3693 if (event_child->step_range_start == event_child->step_range_end)
87ce2a04 3694 debug_printf ("GDB wanted to single-step, reporting event.\n");
c2d6af84 3695 else if (!lwp_in_step_range (event_child))
87ce2a04 3696 debug_printf ("Out of step range, reporting event.\n");
c2d6af84 3697 }
15c66dd6 3698 if (event_child->stop_reason == TARGET_STOPPED_BY_WATCHPOINT)
87ce2a04 3699 debug_printf ("Stopped by watchpoint.\n");
582511be 3700 else if (gdb_breakpoint_here (event_child->stop_pc))
87ce2a04 3701 debug_printf ("Stopped by GDB breakpoint.\n");
6bf5e0ba 3702 if (debug_threads)
87ce2a04 3703 debug_printf ("Hit a non-gdbserver trap event.\n");
6bf5e0ba
PA
3704 }
3705
3706 /* Alright, we're going to report a stop. */
3707
8901d193
YQ
3708 /* Remove reinsert breakpoints. */
3709 if (can_software_single_step ())
3710 {
3711 /* Remove reinsert breakpoints or not. It it is true, stop all
3712 lwps, so that other threads won't hit the breakpoint in the
3713 staled memory. */
3714 int remove_reinsert_breakpoints_p = 0;
3715
3716 if (non_stop)
3717 {
3718 remove_reinsert_breakpoints_p
3719 = has_reinsert_breakpoints (current_thread);
3720 }
3721 else
3722 {
3723 /* In all-stop, a stop reply cancels all previous resume
3724 requests. Delete all reinsert breakpoints. */
3725 struct inferior_list_entry *inf, *tmp;
3726
3727 ALL_INFERIORS (&all_threads, inf, tmp)
3728 {
3729 struct thread_info *thread = (struct thread_info *) inf;
3730
3731 if (has_reinsert_breakpoints (thread))
3732 {
3733 remove_reinsert_breakpoints_p = 1;
3734 break;
3735 }
3736 }
3737 }
3738
3739 if (remove_reinsert_breakpoints_p)
3740 {
3741 /* If we remove reinsert breakpoints from memory, stop all lwps,
3742 so that other threads won't hit the breakpoint in the staled
3743 memory. */
3744 stop_all_lwps (0, event_child);
3745
3746 if (non_stop)
3747 {
3748 gdb_assert (has_reinsert_breakpoints (current_thread));
3749 delete_reinsert_breakpoints (current_thread);
3750 }
3751 else
3752 {
3753 struct inferior_list_entry *inf, *tmp;
3754
3755 ALL_INFERIORS (&all_threads, inf, tmp)
3756 {
3757 struct thread_info *thread = (struct thread_info *) inf;
3758
3759 if (has_reinsert_breakpoints (thread))
3760 delete_reinsert_breakpoints (thread);
3761 }
3762 }
3763
3764 unstop_all_lwps (0, event_child);
3765 }
3766 }
3767
582511be 3768 if (!stabilizing_threads)
6bf5e0ba
PA
3769 {
3770 /* In all-stop, stop all threads. */
582511be
PA
3771 if (!non_stop)
3772 stop_all_lwps (0, NULL);
6bf5e0ba
PA
3773
3774 /* If we're not waiting for a specific LWP, choose an event LWP
3775 from among those that have had events. Giving equal priority
3776 to all LWPs that have had events helps prevent
3777 starvation. */
3778 if (ptid_equal (ptid, minus_one_ptid))
3779 {
3780 event_child->status_pending_p = 1;
3781 event_child->status_pending = w;
3782
3783 select_event_lwp (&event_child);
3784
0bfdf32f
GB
3785 /* current_thread and event_child must stay in sync. */
3786 current_thread = get_lwp_thread (event_child);
ee1e2d4f 3787
6bf5e0ba
PA
3788 event_child->status_pending_p = 0;
3789 w = event_child->status_pending;
3790 }
3791
c03e6ccc 3792 if (step_over_finished)
582511be
PA
3793 {
3794 if (!non_stop)
3795 {
3796 /* If we were doing a step-over, all other threads but
3797 the stepping one had been paused in start_step_over,
3798 with their suspend counts incremented. We don't want
3799 to do a full unstop/unpause, because we're in
3800 all-stop mode (so we want threads stopped), but we
3801 still need to unsuspend the other threads, to
3802 decrement their `suspended' count back. */
3803 unsuspend_all_lwps (event_child);
3804 }
3805 else
3806 {
3807 /* If we just finished a step-over, then all threads had
3808 been momentarily paused. In all-stop, that's fine,
3809 we want threads stopped by now anyway. In non-stop,
3810 we need to re-resume threads that GDB wanted to be
3811 running. */
3812 unstop_all_lwps (1, event_child);
3813 }
3814 }
c03e6ccc 3815
fa593d66 3816 /* Stabilize threads (move out of jump pads). */
582511be
PA
3817 if (!non_stop)
3818 stabilize_threads ();
6bf5e0ba
PA
3819 }
3820 else
3821 {
3822 /* If we just finished a step-over, then all threads had been
3823 momentarily paused. In all-stop, that's fine, we want
3824 threads stopped by now anyway. In non-stop, we need to
3825 re-resume threads that GDB wanted to be running. */
3826 if (step_over_finished)
7984d532 3827 unstop_all_lwps (1, event_child);
6bf5e0ba
PA
3828 }
3829
00db26fa 3830 if (event_child->waitstatus.kind != TARGET_WAITKIND_IGNORE)
de0d863e 3831 {
00db26fa
PA
3832 /* If the reported event is an exit, fork, vfork or exec, let
3833 GDB know. */
3834 *ourstatus = event_child->waitstatus;
de0d863e
DB
3835 /* Clear the event lwp's waitstatus since we handled it already. */
3836 event_child->waitstatus.kind = TARGET_WAITKIND_IGNORE;
3837 }
3838 else
3839 ourstatus->kind = TARGET_WAITKIND_STOPPED;
5b1c542e 3840
582511be 3841 /* Now that we've selected our final event LWP, un-adjust its PC if
3e572f71
PA
3842 it was a software breakpoint, and the client doesn't know we can
3843 adjust the breakpoint ourselves. */
3844 if (event_child->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT
3845 && !swbreak_feature)
582511be
PA
3846 {
3847 int decr_pc = the_low_target.decr_pc_after_break;
3848
3849 if (decr_pc != 0)
3850 {
3851 struct regcache *regcache
3852 = get_thread_regcache (current_thread, 1);
3853 (*the_low_target.set_pc) (regcache, event_child->stop_pc + decr_pc);
3854 }
3855 }
3856
82075af2
JS
3857 if (WSTOPSIG (w) == SYSCALL_SIGTRAP)
3858 {
82075af2 3859 get_syscall_trapinfo (event_child,
4cc32bec 3860 &ourstatus->value.syscall_number);
82075af2
JS
3861 ourstatus->kind = event_child->syscall_state;
3862 }
3863 else if (current_thread->last_resume_kind == resume_stop
3864 && WSTOPSIG (w) == SIGSTOP)
bd99dc85
PA
3865 {
3866 /* A thread that has been requested to stop by GDB with vCont;t,
3867 and it stopped cleanly, so report as SIG0. The use of
3868 SIGSTOP is an implementation detail. */
a493e3e2 3869 ourstatus->value.sig = GDB_SIGNAL_0;
bd99dc85 3870 }
0bfdf32f 3871 else if (current_thread->last_resume_kind == resume_stop
8336d594 3872 && WSTOPSIG (w) != SIGSTOP)
bd99dc85
PA
3873 {
3874 /* A thread that has been requested to stop by GDB with vCont;t,
d50171e4 3875 but, it stopped for other reasons. */
2ea28649 3876 ourstatus->value.sig = gdb_signal_from_host (WSTOPSIG (w));
bd99dc85 3877 }
de0d863e 3878 else if (ourstatus->kind == TARGET_WAITKIND_STOPPED)
bd99dc85 3879 {
2ea28649 3880 ourstatus->value.sig = gdb_signal_from_host (WSTOPSIG (w));
bd99dc85
PA
3881 }
3882
d50171e4
PA
3883 gdb_assert (ptid_equal (step_over_bkpt, null_ptid));
3884
bd99dc85 3885 if (debug_threads)
87ce2a04
DE
3886 {
3887 debug_printf ("linux_wait_1 ret = %s, %d, %d\n",
0bfdf32f 3888 target_pid_to_str (ptid_of (current_thread)),
87ce2a04
DE
3889 ourstatus->kind, ourstatus->value.sig);
3890 debug_exit ();
3891 }
bd99dc85 3892
65706a29
PA
3893 if (ourstatus->kind == TARGET_WAITKIND_EXITED)
3894 return filter_exit_event (event_child, ourstatus);
3895
0bfdf32f 3896 return ptid_of (current_thread);
bd99dc85
PA
3897}
3898
3899/* Get rid of any pending event in the pipe. */
3900static void
3901async_file_flush (void)
3902{
3903 int ret;
3904 char buf;
3905
3906 do
3907 ret = read (linux_event_pipe[0], &buf, 1);
3908 while (ret >= 0 || (ret == -1 && errno == EINTR));
3909}
3910
3911/* Put something in the pipe, so the event loop wakes up. */
3912static void
3913async_file_mark (void)
3914{
3915 int ret;
3916
3917 async_file_flush ();
3918
3919 do
3920 ret = write (linux_event_pipe[1], "+", 1);
3921 while (ret == 0 || (ret == -1 && errno == EINTR));
3922
3923 /* Ignore EAGAIN. If the pipe is full, the event loop will already
3924 be awakened anyway. */
3925}
3926
95954743
PA
3927static ptid_t
3928linux_wait (ptid_t ptid,
3929 struct target_waitstatus *ourstatus, int target_options)
bd99dc85 3930{
95954743 3931 ptid_t event_ptid;
bd99dc85 3932
bd99dc85
PA
3933 /* Flush the async file first. */
3934 if (target_is_async_p ())
3935 async_file_flush ();
3936
582511be
PA
3937 do
3938 {
3939 event_ptid = linux_wait_1 (ptid, ourstatus, target_options);
3940 }
3941 while ((target_options & TARGET_WNOHANG) == 0
3942 && ptid_equal (event_ptid, null_ptid)
3943 && ourstatus->kind == TARGET_WAITKIND_IGNORE);
bd99dc85
PA
3944
3945 /* If at least one stop was reported, there may be more. A single
3946 SIGCHLD can signal more than one child stop. */
3947 if (target_is_async_p ()
3948 && (target_options & TARGET_WNOHANG) != 0
95954743 3949 && !ptid_equal (event_ptid, null_ptid))
bd99dc85
PA
3950 async_file_mark ();
3951
3952 return event_ptid;
da6d8c04
DJ
3953}
3954
c5f62d5f 3955/* Send a signal to an LWP. */
fd500816
DJ
3956
3957static int
a1928bad 3958kill_lwp (unsigned long lwpid, int signo)
fd500816 3959{
4a6ed09b 3960 int ret;
fd500816 3961
4a6ed09b
PA
3962 errno = 0;
3963 ret = syscall (__NR_tkill, lwpid, signo);
3964 if (errno == ENOSYS)
3965 {
3966 /* If tkill fails, then we are not using nptl threads, a
3967 configuration we no longer support. */
3968 perror_with_name (("tkill"));
3969 }
3970 return ret;
fd500816
DJ
3971}
3972
964e4306
PA
3973void
3974linux_stop_lwp (struct lwp_info *lwp)
3975{
3976 send_sigstop (lwp);
3977}
3978
0d62e5e8 3979static void
02fc4de7 3980send_sigstop (struct lwp_info *lwp)
0d62e5e8 3981{
bd99dc85 3982 int pid;
0d62e5e8 3983
d86d4aaf 3984 pid = lwpid_of (get_lwp_thread (lwp));
bd99dc85 3985
0d62e5e8
DJ
3986 /* If we already have a pending stop signal for this process, don't
3987 send another. */
54a0b537 3988 if (lwp->stop_expected)
0d62e5e8 3989 {
ae13219e 3990 if (debug_threads)
87ce2a04 3991 debug_printf ("Have pending sigstop for lwp %d\n", pid);
ae13219e 3992
0d62e5e8
DJ
3993 return;
3994 }
3995
3996 if (debug_threads)
87ce2a04 3997 debug_printf ("Sending sigstop to lwp %d\n", pid);
0d62e5e8 3998
d50171e4 3999 lwp->stop_expected = 1;
bd99dc85 4000 kill_lwp (pid, SIGSTOP);
0d62e5e8
DJ
4001}
4002
7984d532
PA
4003static int
4004send_sigstop_callback (struct inferior_list_entry *entry, void *except)
02fc4de7 4005{
d86d4aaf
DE
4006 struct thread_info *thread = (struct thread_info *) entry;
4007 struct lwp_info *lwp = get_thread_lwp (thread);
02fc4de7 4008
7984d532
PA
4009 /* Ignore EXCEPT. */
4010 if (lwp == except)
4011 return 0;
4012
02fc4de7 4013 if (lwp->stopped)
7984d532 4014 return 0;
02fc4de7
PA
4015
4016 send_sigstop (lwp);
7984d532
PA
4017 return 0;
4018}
4019
4020/* Increment the suspend count of an LWP, and stop it, if not stopped
4021 yet. */
4022static int
4023suspend_and_send_sigstop_callback (struct inferior_list_entry *entry,
4024 void *except)
4025{
d86d4aaf
DE
4026 struct thread_info *thread = (struct thread_info *) entry;
4027 struct lwp_info *lwp = get_thread_lwp (thread);
7984d532
PA
4028
4029 /* Ignore EXCEPT. */
4030 if (lwp == except)
4031 return 0;
4032
863d01bd 4033 lwp_suspended_inc (lwp);
7984d532
PA
4034
4035 return send_sigstop_callback (entry, except);
02fc4de7
PA
4036}
4037
95954743
PA
4038static void
4039mark_lwp_dead (struct lwp_info *lwp, int wstat)
4040{
95954743
PA
4041 /* Store the exit status for later. */
4042 lwp->status_pending_p = 1;
4043 lwp->status_pending = wstat;
4044
00db26fa
PA
4045 /* Store in waitstatus as well, as there's nothing else to process
4046 for this event. */
4047 if (WIFEXITED (wstat))
4048 {
4049 lwp->waitstatus.kind = TARGET_WAITKIND_EXITED;
4050 lwp->waitstatus.value.integer = WEXITSTATUS (wstat);
4051 }
4052 else if (WIFSIGNALED (wstat))
4053 {
4054 lwp->waitstatus.kind = TARGET_WAITKIND_SIGNALLED;
4055 lwp->waitstatus.value.sig = gdb_signal_from_host (WTERMSIG (wstat));
4056 }
4057
95954743
PA
4058 /* Prevent trying to stop it. */
4059 lwp->stopped = 1;
4060
4061 /* No further stops are expected from a dead lwp. */
4062 lwp->stop_expected = 0;
4063}
4064
00db26fa
PA
4065/* Return true if LWP has exited already, and has a pending exit event
4066 to report to GDB. */
4067
4068static int
4069lwp_is_marked_dead (struct lwp_info *lwp)
4070{
4071 return (lwp->status_pending_p
4072 && (WIFEXITED (lwp->status_pending)
4073 || WIFSIGNALED (lwp->status_pending)));
4074}
4075
fa96cb38
PA
4076/* Wait for all children to stop for the SIGSTOPs we just queued. */
4077
0d62e5e8 4078static void
fa96cb38 4079wait_for_sigstop (void)
0d62e5e8 4080{
0bfdf32f 4081 struct thread_info *saved_thread;
95954743 4082 ptid_t saved_tid;
fa96cb38
PA
4083 int wstat;
4084 int ret;
0d62e5e8 4085
0bfdf32f
GB
4086 saved_thread = current_thread;
4087 if (saved_thread != NULL)
4088 saved_tid = saved_thread->entry.id;
bd99dc85 4089 else
95954743 4090 saved_tid = null_ptid; /* avoid bogus unused warning */
bd99dc85 4091
d50171e4 4092 if (debug_threads)
fa96cb38 4093 debug_printf ("wait_for_sigstop: pulling events\n");
d50171e4 4094
fa96cb38
PA
4095 /* Passing NULL_PTID as filter indicates we want all events to be
4096 left pending. Eventually this returns when there are no
4097 unwaited-for children left. */
4098 ret = linux_wait_for_event_filtered (minus_one_ptid, null_ptid,
4099 &wstat, __WALL);
4100 gdb_assert (ret == -1);
0d62e5e8 4101
0bfdf32f
GB
4102 if (saved_thread == NULL || linux_thread_alive (saved_tid))
4103 current_thread = saved_thread;
0d62e5e8
DJ
4104 else
4105 {
4106 if (debug_threads)
87ce2a04 4107 debug_printf ("Previously current thread died.\n");
0d62e5e8 4108
f0db101d
PA
4109 /* We can't change the current inferior behind GDB's back,
4110 otherwise, a subsequent command may apply to the wrong
4111 process. */
4112 current_thread = NULL;
0d62e5e8
DJ
4113 }
4114}
4115
fa593d66
PA
4116/* Returns true if LWP ENTRY is stopped in a jump pad, and we can't
4117 move it out, because we need to report the stop event to GDB. For
4118 example, if the user puts a breakpoint in the jump pad, it's
4119 because she wants to debug it. */
4120
4121static int
4122stuck_in_jump_pad_callback (struct inferior_list_entry *entry, void *data)
4123{
d86d4aaf
DE
4124 struct thread_info *thread = (struct thread_info *) entry;
4125 struct lwp_info *lwp = get_thread_lwp (thread);
fa593d66 4126
863d01bd
PA
4127 if (lwp->suspended != 0)
4128 {
4129 internal_error (__FILE__, __LINE__,
4130 "LWP %ld is suspended, suspended=%d\n",
4131 lwpid_of (thread), lwp->suspended);
4132 }
fa593d66
PA
4133 gdb_assert (lwp->stopped);
4134
4135 /* Allow debugging the jump pad, gdb_collect, etc.. */
4136 return (supports_fast_tracepoints ()
58b4daa5 4137 && agent_loaded_p ()
fa593d66 4138 && (gdb_breakpoint_here (lwp->stop_pc)
15c66dd6 4139 || lwp->stop_reason == TARGET_STOPPED_BY_WATCHPOINT
fa593d66
PA
4140 || thread->last_resume_kind == resume_step)
4141 && linux_fast_tracepoint_collecting (lwp, NULL));
4142}
4143
4144static void
4145move_out_of_jump_pad_callback (struct inferior_list_entry *entry)
4146{
d86d4aaf 4147 struct thread_info *thread = (struct thread_info *) entry;
f0ce0d3a 4148 struct thread_info *saved_thread;
d86d4aaf 4149 struct lwp_info *lwp = get_thread_lwp (thread);
fa593d66
PA
4150 int *wstat;
4151
863d01bd
PA
4152 if (lwp->suspended != 0)
4153 {
4154 internal_error (__FILE__, __LINE__,
4155 "LWP %ld is suspended, suspended=%d\n",
4156 lwpid_of (thread), lwp->suspended);
4157 }
fa593d66
PA
4158 gdb_assert (lwp->stopped);
4159
f0ce0d3a
PA
4160 /* For gdb_breakpoint_here. */
4161 saved_thread = current_thread;
4162 current_thread = thread;
4163
fa593d66
PA
4164 wstat = lwp->status_pending_p ? &lwp->status_pending : NULL;
4165
4166 /* Allow debugging the jump pad, gdb_collect, etc. */
4167 if (!gdb_breakpoint_here (lwp->stop_pc)
15c66dd6 4168 && lwp->stop_reason != TARGET_STOPPED_BY_WATCHPOINT
fa593d66
PA
4169 && thread->last_resume_kind != resume_step
4170 && maybe_move_out_of_jump_pad (lwp, wstat))
4171 {
4172 if (debug_threads)
87ce2a04 4173 debug_printf ("LWP %ld needs stabilizing (in jump pad)\n",
d86d4aaf 4174 lwpid_of (thread));
fa593d66
PA
4175
4176 if (wstat)
4177 {
4178 lwp->status_pending_p = 0;
4179 enqueue_one_deferred_signal (lwp, wstat);
4180
4181 if (debug_threads)
87ce2a04
DE
4182 debug_printf ("Signal %d for LWP %ld deferred "
4183 "(in jump pad)\n",
d86d4aaf 4184 WSTOPSIG (*wstat), lwpid_of (thread));
fa593d66
PA
4185 }
4186
4187 linux_resume_one_lwp (lwp, 0, 0, NULL);
4188 }
4189 else
863d01bd 4190 lwp_suspended_inc (lwp);
f0ce0d3a
PA
4191
4192 current_thread = saved_thread;
fa593d66
PA
4193}
4194
4195static int
4196lwp_running (struct inferior_list_entry *entry, void *data)
4197{
d86d4aaf
DE
4198 struct thread_info *thread = (struct thread_info *) entry;
4199 struct lwp_info *lwp = get_thread_lwp (thread);
fa593d66 4200
00db26fa 4201 if (lwp_is_marked_dead (lwp))
fa593d66
PA
4202 return 0;
4203 if (lwp->stopped)
4204 return 0;
4205 return 1;
4206}
4207
7984d532
PA
4208/* Stop all lwps that aren't stopped yet, except EXCEPT, if not NULL.
4209 If SUSPEND, then also increase the suspend count of every LWP,
4210 except EXCEPT. */
4211
0d62e5e8 4212static void
7984d532 4213stop_all_lwps (int suspend, struct lwp_info *except)
0d62e5e8 4214{
bde24c0a
PA
4215 /* Should not be called recursively. */
4216 gdb_assert (stopping_threads == NOT_STOPPING_THREADS);
4217
87ce2a04
DE
4218 if (debug_threads)
4219 {
4220 debug_enter ();
4221 debug_printf ("stop_all_lwps (%s, except=%s)\n",
4222 suspend ? "stop-and-suspend" : "stop",
4223 except != NULL
d86d4aaf 4224 ? target_pid_to_str (ptid_of (get_lwp_thread (except)))
87ce2a04
DE
4225 : "none");
4226 }
4227
bde24c0a
PA
4228 stopping_threads = (suspend
4229 ? STOPPING_AND_SUSPENDING_THREADS
4230 : STOPPING_THREADS);
7984d532
PA
4231
4232 if (suspend)
d86d4aaf 4233 find_inferior (&all_threads, suspend_and_send_sigstop_callback, except);
7984d532 4234 else
d86d4aaf 4235 find_inferior (&all_threads, send_sigstop_callback, except);
fa96cb38 4236 wait_for_sigstop ();
bde24c0a 4237 stopping_threads = NOT_STOPPING_THREADS;
87ce2a04
DE
4238
4239 if (debug_threads)
4240 {
4241 debug_printf ("stop_all_lwps done, setting stopping_threads "
4242 "back to !stopping\n");
4243 debug_exit ();
4244 }
0d62e5e8
DJ
4245}
4246
863d01bd
PA
4247/* Enqueue one signal in the chain of signals which need to be
4248 delivered to this process on next resume. */
4249
4250static void
4251enqueue_pending_signal (struct lwp_info *lwp, int signal, siginfo_t *info)
4252{
8d749320 4253 struct pending_signals *p_sig = XNEW (struct pending_signals);
863d01bd 4254
863d01bd
PA
4255 p_sig->prev = lwp->pending_signals;
4256 p_sig->signal = signal;
4257 if (info == NULL)
4258 memset (&p_sig->info, 0, sizeof (siginfo_t));
4259 else
4260 memcpy (&p_sig->info, info, sizeof (siginfo_t));
4261 lwp->pending_signals = p_sig;
4262}
4263
fa5308bd
AT
4264/* Install breakpoints for software single stepping. */
4265
4266static void
4267install_software_single_step_breakpoints (struct lwp_info *lwp)
4268{
4269 int i;
4270 CORE_ADDR pc;
984a2c04
YQ
4271 struct thread_info *thread = get_lwp_thread (lwp);
4272 struct regcache *regcache = get_thread_regcache (thread, 1);
fa5308bd 4273 VEC (CORE_ADDR) *next_pcs = NULL;
984a2c04
YQ
4274 struct cleanup *old_chain = make_cleanup_restore_current_thread ();
4275
4276 make_cleanup (VEC_cleanup (CORE_ADDR), &next_pcs);
fa5308bd 4277
984a2c04 4278 current_thread = thread;
4d18591b 4279 next_pcs = (*the_low_target.get_next_pcs) (regcache);
fa5308bd
AT
4280
4281 for (i = 0; VEC_iterate (CORE_ADDR, next_pcs, i, pc); ++i)
bec903c9 4282 set_reinsert_breakpoint (pc, current_ptid);
fa5308bd
AT
4283
4284 do_cleanups (old_chain);
4285}
4286
7fe5e27e
AT
4287/* Single step via hardware or software single step.
4288 Return 1 if hardware single stepping, 0 if software single stepping
4289 or can't single step. */
4290
4291static int
4292single_step (struct lwp_info* lwp)
4293{
4294 int step = 0;
4295
4296 if (can_hardware_single_step ())
4297 {
4298 step = 1;
4299 }
4300 else if (can_software_single_step ())
4301 {
4302 install_software_single_step_breakpoints (lwp);
4303 step = 0;
4304 }
4305 else
4306 {
4307 if (debug_threads)
4308 debug_printf ("stepping is not implemented on this target");
4309 }
4310
4311 return step;
4312}
4313
35ac8b3e 4314/* The signal can be delivered to the inferior if we are not trying to
5b061e98
YQ
4315 finish a fast tracepoint collect. Since signal can be delivered in
4316 the step-over, the program may go to signal handler and trap again
4317 after return from the signal handler. We can live with the spurious
4318 double traps. */
35ac8b3e
YQ
4319
4320static int
4321lwp_signal_can_be_delivered (struct lwp_info *lwp)
4322{
484b3c32 4323 return !lwp->collecting_fast_tracepoint;
35ac8b3e
YQ
4324}
4325
23f238d3
PA
4326/* Resume execution of LWP. If STEP is nonzero, single-step it. If
4327 SIGNAL is nonzero, give it that signal. */
da6d8c04 4328
ce3a066d 4329static void
23f238d3
PA
4330linux_resume_one_lwp_throw (struct lwp_info *lwp,
4331 int step, int signal, siginfo_t *info)
da6d8c04 4332{
d86d4aaf 4333 struct thread_info *thread = get_lwp_thread (lwp);
0bfdf32f 4334 struct thread_info *saved_thread;
fa593d66 4335 int fast_tp_collecting;
82075af2 4336 int ptrace_request;
c06cbd92
YQ
4337 struct process_info *proc = get_thread_process (thread);
4338
4339 /* Note that target description may not be initialised
4340 (proc->tdesc == NULL) at this point because the program hasn't
4341 stopped at the first instruction yet. It means GDBserver skips
4342 the extra traps from the wrapper program (see option --wrapper).
4343 Code in this function that requires register access should be
4344 guarded by proc->tdesc == NULL or something else. */
0d62e5e8 4345
54a0b537 4346 if (lwp->stopped == 0)
0d62e5e8
DJ
4347 return;
4348
65706a29
PA
4349 gdb_assert (lwp->waitstatus.kind == TARGET_WAITKIND_IGNORE);
4350
fa593d66
PA
4351 fast_tp_collecting = lwp->collecting_fast_tracepoint;
4352
4353 gdb_assert (!stabilizing_threads || fast_tp_collecting);
4354
219f2f23
PA
4355 /* Cancel actions that rely on GDB not changing the PC (e.g., the
4356 user used the "jump" command, or "set $pc = foo"). */
c06cbd92 4357 if (thread->while_stepping != NULL && lwp->stop_pc != get_pc (lwp))
219f2f23
PA
4358 {
4359 /* Collecting 'while-stepping' actions doesn't make sense
4360 anymore. */
d86d4aaf 4361 release_while_stepping_state_list (thread);
219f2f23
PA
4362 }
4363
0d62e5e8 4364 /* If we have pending signals or status, and a new signal, enqueue the
35ac8b3e
YQ
4365 signal. Also enqueue the signal if it can't be delivered to the
4366 inferior right now. */
0d62e5e8 4367 if (signal != 0
fa593d66
PA
4368 && (lwp->status_pending_p
4369 || lwp->pending_signals != NULL
35ac8b3e 4370 || !lwp_signal_can_be_delivered (lwp)))
94610ec4
YQ
4371 {
4372 enqueue_pending_signal (lwp, signal, info);
4373
4374 /* Postpone any pending signal. It was enqueued above. */
4375 signal = 0;
4376 }
0d62e5e8 4377
d50171e4
PA
4378 if (lwp->status_pending_p)
4379 {
4380 if (debug_threads)
94610ec4 4381 debug_printf ("Not resuming lwp %ld (%s, stop %s);"
87ce2a04 4382 " has pending status\n",
94610ec4 4383 lwpid_of (thread), step ? "step" : "continue",
87ce2a04 4384 lwp->stop_expected ? "expected" : "not expected");
d50171e4
PA
4385 return;
4386 }
0d62e5e8 4387
0bfdf32f
GB
4388 saved_thread = current_thread;
4389 current_thread = thread;
0d62e5e8 4390
0d62e5e8
DJ
4391 /* This bit needs some thinking about. If we get a signal that
4392 we must report while a single-step reinsert is still pending,
4393 we often end up resuming the thread. It might be better to
4394 (ew) allow a stack of pending events; then we could be sure that
4395 the reinsert happened right away and not lose any signals.
4396
4397 Making this stack would also shrink the window in which breakpoints are
54a0b537 4398 uninserted (see comment in linux_wait_for_lwp) but not enough for
0d62e5e8
DJ
4399 complete correctness, so it won't solve that problem. It may be
4400 worthwhile just to solve this one, however. */
54a0b537 4401 if (lwp->bp_reinsert != 0)
0d62e5e8
DJ
4402 {
4403 if (debug_threads)
87ce2a04
DE
4404 debug_printf (" pending reinsert at 0x%s\n",
4405 paddress (lwp->bp_reinsert));
d50171e4 4406
85e00e85 4407 if (can_hardware_single_step ())
d50171e4 4408 {
fa593d66
PA
4409 if (fast_tp_collecting == 0)
4410 {
4411 if (step == 0)
4412 fprintf (stderr, "BAD - reinserting but not stepping.\n");
4413 if (lwp->suspended)
4414 fprintf (stderr, "BAD - reinserting and suspended(%d).\n",
4415 lwp->suspended);
4416 }
d50171e4 4417 }
f79b145d
YQ
4418
4419 step = maybe_hw_step (thread);
0d62e5e8
DJ
4420 }
4421
fa593d66
PA
4422 if (fast_tp_collecting == 1)
4423 {
4424 if (debug_threads)
87ce2a04
DE
4425 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
4426 " (exit-jump-pad-bkpt)\n",
d86d4aaf 4427 lwpid_of (thread));
fa593d66
PA
4428 }
4429 else if (fast_tp_collecting == 2)
4430 {
4431 if (debug_threads)
87ce2a04
DE
4432 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
4433 " single-stepping\n",
d86d4aaf 4434 lwpid_of (thread));
fa593d66
PA
4435
4436 if (can_hardware_single_step ())
4437 step = 1;
4438 else
38e08fca
GB
4439 {
4440 internal_error (__FILE__, __LINE__,
4441 "moving out of jump pad single-stepping"
4442 " not implemented on this target");
4443 }
fa593d66
PA
4444 }
4445
219f2f23
PA
4446 /* If we have while-stepping actions in this thread set it stepping.
4447 If we have a signal to deliver, it may or may not be set to
4448 SIG_IGN, we don't know. Assume so, and allow collecting
4449 while-stepping into a signal handler. A possible smart thing to
4450 do would be to set an internal breakpoint at the signal return
4451 address, continue, and carry on catching this while-stepping
4452 action only when that breakpoint is hit. A future
4453 enhancement. */
7fe5e27e 4454 if (thread->while_stepping != NULL)
219f2f23
PA
4455 {
4456 if (debug_threads)
87ce2a04 4457 debug_printf ("lwp %ld has a while-stepping action -> forcing step.\n",
d86d4aaf 4458 lwpid_of (thread));
7fe5e27e
AT
4459
4460 step = single_step (lwp);
219f2f23
PA
4461 }
4462
c06cbd92 4463 if (proc->tdesc != NULL && the_low_target.get_pc != NULL)
0d62e5e8 4464 {
0bfdf32f 4465 struct regcache *regcache = get_thread_regcache (current_thread, 1);
582511be
PA
4466
4467 lwp->stop_pc = (*the_low_target.get_pc) (regcache);
4468
4469 if (debug_threads)
4470 {
4471 debug_printf (" %s from pc 0x%lx\n", step ? "step" : "continue",
4472 (long) lwp->stop_pc);
4473 }
0d62e5e8
DJ
4474 }
4475
35ac8b3e
YQ
4476 /* If we have pending signals, consume one if it can be delivered to
4477 the inferior. */
4478 if (lwp->pending_signals != NULL && lwp_signal_can_be_delivered (lwp))
0d62e5e8
DJ
4479 {
4480 struct pending_signals **p_sig;
4481
54a0b537 4482 p_sig = &lwp->pending_signals;
0d62e5e8
DJ
4483 while ((*p_sig)->prev != NULL)
4484 p_sig = &(*p_sig)->prev;
4485
4486 signal = (*p_sig)->signal;
32ca6d61 4487 if ((*p_sig)->info.si_signo != 0)
d86d4aaf 4488 ptrace (PTRACE_SETSIGINFO, lwpid_of (thread), (PTRACE_TYPE_ARG3) 0,
56f7af9c 4489 &(*p_sig)->info);
32ca6d61 4490
0d62e5e8
DJ
4491 free (*p_sig);
4492 *p_sig = NULL;
4493 }
4494
94610ec4
YQ
4495 if (debug_threads)
4496 debug_printf ("Resuming lwp %ld (%s, signal %d, stop %s)\n",
4497 lwpid_of (thread), step ? "step" : "continue", signal,
4498 lwp->stop_expected ? "expected" : "not expected");
4499
aa5ca48f
DE
4500 if (the_low_target.prepare_to_resume != NULL)
4501 the_low_target.prepare_to_resume (lwp);
4502
d86d4aaf 4503 regcache_invalidate_thread (thread);
da6d8c04 4504 errno = 0;
54a0b537 4505 lwp->stepping = step;
82075af2
JS
4506 if (step)
4507 ptrace_request = PTRACE_SINGLESTEP;
4508 else if (gdb_catching_syscalls_p (lwp))
4509 ptrace_request = PTRACE_SYSCALL;
4510 else
4511 ptrace_request = PTRACE_CONT;
4512 ptrace (ptrace_request,
4513 lwpid_of (thread),
b8e1b30e 4514 (PTRACE_TYPE_ARG3) 0,
14ce3065
DE
4515 /* Coerce to a uintptr_t first to avoid potential gcc warning
4516 of coercing an 8 byte integer to a 4 byte pointer. */
b8e1b30e 4517 (PTRACE_TYPE_ARG4) (uintptr_t) signal);
0d62e5e8 4518
0bfdf32f 4519 current_thread = saved_thread;
da6d8c04 4520 if (errno)
23f238d3
PA
4521 perror_with_name ("resuming thread");
4522
4523 /* Successfully resumed. Clear state that no longer makes sense,
4524 and mark the LWP as running. Must not do this before resuming
4525 otherwise if that fails other code will be confused. E.g., we'd
4526 later try to stop the LWP and hang forever waiting for a stop
4527 status. Note that we must not throw after this is cleared,
4528 otherwise handle_zombie_lwp_error would get confused. */
4529 lwp->stopped = 0;
4530 lwp->stop_reason = TARGET_STOPPED_BY_NO_REASON;
4531}
4532
4533/* Called when we try to resume a stopped LWP and that errors out. If
4534 the LWP is no longer in ptrace-stopped state (meaning it's zombie,
4535 or about to become), discard the error, clear any pending status
4536 the LWP may have, and return true (we'll collect the exit status
4537 soon enough). Otherwise, return false. */
4538
4539static int
4540check_ptrace_stopped_lwp_gone (struct lwp_info *lp)
4541{
4542 struct thread_info *thread = get_lwp_thread (lp);
4543
4544 /* If we get an error after resuming the LWP successfully, we'd
4545 confuse !T state for the LWP being gone. */
4546 gdb_assert (lp->stopped);
4547
4548 /* We can't just check whether the LWP is in 'Z (Zombie)' state,
4549 because even if ptrace failed with ESRCH, the tracee may be "not
4550 yet fully dead", but already refusing ptrace requests. In that
4551 case the tracee has 'R (Running)' state for a little bit
4552 (observed in Linux 3.18). See also the note on ESRCH in the
4553 ptrace(2) man page. Instead, check whether the LWP has any state
4554 other than ptrace-stopped. */
4555
4556 /* Don't assume anything if /proc/PID/status can't be read. */
4557 if (linux_proc_pid_is_trace_stopped_nowarn (lwpid_of (thread)) == 0)
3221518c 4558 {
23f238d3
PA
4559 lp->stop_reason = TARGET_STOPPED_BY_NO_REASON;
4560 lp->status_pending_p = 0;
4561 return 1;
4562 }
4563 return 0;
4564}
4565
4566/* Like linux_resume_one_lwp_throw, but no error is thrown if the LWP
4567 disappears while we try to resume it. */
3221518c 4568
23f238d3
PA
4569static void
4570linux_resume_one_lwp (struct lwp_info *lwp,
4571 int step, int signal, siginfo_t *info)
4572{
4573 TRY
4574 {
4575 linux_resume_one_lwp_throw (lwp, step, signal, info);
4576 }
4577 CATCH (ex, RETURN_MASK_ERROR)
4578 {
4579 if (!check_ptrace_stopped_lwp_gone (lwp))
4580 throw_exception (ex);
3221518c 4581 }
23f238d3 4582 END_CATCH
da6d8c04
DJ
4583}
4584
2bd7c093
PA
4585struct thread_resume_array
4586{
4587 struct thread_resume *resume;
4588 size_t n;
4589};
64386c31 4590
ebcf782c
DE
4591/* This function is called once per thread via find_inferior.
4592 ARG is a pointer to a thread_resume_array struct.
4593 We look up the thread specified by ENTRY in ARG, and mark the thread
4594 with a pointer to the appropriate resume request.
5544ad89
DJ
4595
4596 This algorithm is O(threads * resume elements), but resume elements
4597 is small (and will remain small at least until GDB supports thread
4598 suspension). */
ebcf782c 4599
2bd7c093
PA
4600static int
4601linux_set_resume_request (struct inferior_list_entry *entry, void *arg)
0d62e5e8 4602{
d86d4aaf
DE
4603 struct thread_info *thread = (struct thread_info *) entry;
4604 struct lwp_info *lwp = get_thread_lwp (thread);
5544ad89 4605 int ndx;
2bd7c093 4606 struct thread_resume_array *r;
64386c31 4607
9a3c8263 4608 r = (struct thread_resume_array *) arg;
64386c31 4609
2bd7c093 4610 for (ndx = 0; ndx < r->n; ndx++)
95954743
PA
4611 {
4612 ptid_t ptid = r->resume[ndx].thread;
4613 if (ptid_equal (ptid, minus_one_ptid)
4614 || ptid_equal (ptid, entry->id)
0c9070b3
YQ
4615 /* Handle both 'pPID' and 'pPID.-1' as meaning 'all threads
4616 of PID'. */
d86d4aaf 4617 || (ptid_get_pid (ptid) == pid_of (thread)
0c9070b3
YQ
4618 && (ptid_is_pid (ptid)
4619 || ptid_get_lwp (ptid) == -1)))
95954743 4620 {
d50171e4 4621 if (r->resume[ndx].kind == resume_stop
8336d594 4622 && thread->last_resume_kind == resume_stop)
d50171e4
PA
4623 {
4624 if (debug_threads)
87ce2a04
DE
4625 debug_printf ("already %s LWP %ld at GDB's request\n",
4626 (thread->last_status.kind
4627 == TARGET_WAITKIND_STOPPED)
4628 ? "stopped"
4629 : "stopping",
d86d4aaf 4630 lwpid_of (thread));
d50171e4
PA
4631
4632 continue;
4633 }
4634
95954743 4635 lwp->resume = &r->resume[ndx];
8336d594 4636 thread->last_resume_kind = lwp->resume->kind;
fa593d66 4637
c2d6af84
PA
4638 lwp->step_range_start = lwp->resume->step_range_start;
4639 lwp->step_range_end = lwp->resume->step_range_end;
4640
fa593d66
PA
4641 /* If we had a deferred signal to report, dequeue one now.
4642 This can happen if LWP gets more than one signal while
4643 trying to get out of a jump pad. */
4644 if (lwp->stopped
4645 && !lwp->status_pending_p
4646 && dequeue_one_deferred_signal (lwp, &lwp->status_pending))
4647 {
4648 lwp->status_pending_p = 1;
4649
4650 if (debug_threads)
87ce2a04
DE
4651 debug_printf ("Dequeueing deferred signal %d for LWP %ld, "
4652 "leaving status pending.\n",
d86d4aaf
DE
4653 WSTOPSIG (lwp->status_pending),
4654 lwpid_of (thread));
fa593d66
PA
4655 }
4656
95954743
PA
4657 return 0;
4658 }
4659 }
2bd7c093
PA
4660
4661 /* No resume action for this thread. */
4662 lwp->resume = NULL;
64386c31 4663
2bd7c093 4664 return 0;
5544ad89
DJ
4665}
4666
20ad9378
DE
4667/* find_inferior callback for linux_resume.
4668 Set *FLAG_P if this lwp has an interesting status pending. */
5544ad89 4669
bd99dc85
PA
4670static int
4671resume_status_pending_p (struct inferior_list_entry *entry, void *flag_p)
5544ad89 4672{
d86d4aaf
DE
4673 struct thread_info *thread = (struct thread_info *) entry;
4674 struct lwp_info *lwp = get_thread_lwp (thread);
5544ad89 4675
bd99dc85
PA
4676 /* LWPs which will not be resumed are not interesting, because
4677 we might not wait for them next time through linux_wait. */
2bd7c093 4678 if (lwp->resume == NULL)
bd99dc85 4679 return 0;
64386c31 4680
582511be 4681 if (thread_still_has_status_pending_p (thread))
d50171e4
PA
4682 * (int *) flag_p = 1;
4683
4684 return 0;
4685}
4686
4687/* Return 1 if this lwp that GDB wants running is stopped at an
4688 internal breakpoint that we need to step over. It assumes that any
4689 required STOP_PC adjustment has already been propagated to the
4690 inferior's regcache. */
4691
4692static int
4693need_step_over_p (struct inferior_list_entry *entry, void *dummy)
4694{
d86d4aaf
DE
4695 struct thread_info *thread = (struct thread_info *) entry;
4696 struct lwp_info *lwp = get_thread_lwp (thread);
0bfdf32f 4697 struct thread_info *saved_thread;
d50171e4 4698 CORE_ADDR pc;
c06cbd92
YQ
4699 struct process_info *proc = get_thread_process (thread);
4700
4701 /* GDBserver is skipping the extra traps from the wrapper program,
4702 don't have to do step over. */
4703 if (proc->tdesc == NULL)
4704 return 0;
d50171e4
PA
4705
4706 /* LWPs which will not be resumed are not interesting, because we
4707 might not wait for them next time through linux_wait. */
4708
4709 if (!lwp->stopped)
4710 {
4711 if (debug_threads)
87ce2a04 4712 debug_printf ("Need step over [LWP %ld]? Ignoring, not stopped\n",
d86d4aaf 4713 lwpid_of (thread));
d50171e4
PA
4714 return 0;
4715 }
4716
8336d594 4717 if (thread->last_resume_kind == resume_stop)
d50171e4
PA
4718 {
4719 if (debug_threads)
87ce2a04
DE
4720 debug_printf ("Need step over [LWP %ld]? Ignoring, should remain"
4721 " stopped\n",
d86d4aaf 4722 lwpid_of (thread));
d50171e4
PA
4723 return 0;
4724 }
4725
7984d532
PA
4726 gdb_assert (lwp->suspended >= 0);
4727
4728 if (lwp->suspended)
4729 {
4730 if (debug_threads)
87ce2a04 4731 debug_printf ("Need step over [LWP %ld]? Ignoring, suspended\n",
d86d4aaf 4732 lwpid_of (thread));
7984d532
PA
4733 return 0;
4734 }
4735
bd99dc85 4736 if (lwp->status_pending_p)
d50171e4
PA
4737 {
4738 if (debug_threads)
87ce2a04
DE
4739 debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
4740 " status.\n",
d86d4aaf 4741 lwpid_of (thread));
d50171e4
PA
4742 return 0;
4743 }
4744
4745 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
4746 or we have. */
4747 pc = get_pc (lwp);
4748
4749 /* If the PC has changed since we stopped, then don't do anything,
4750 and let the breakpoint/tracepoint be hit. This happens if, for
4751 instance, GDB handled the decr_pc_after_break subtraction itself,
4752 GDB is OOL stepping this thread, or the user has issued a "jump"
4753 command, or poked thread's registers herself. */
4754 if (pc != lwp->stop_pc)
4755 {
4756 if (debug_threads)
87ce2a04
DE
4757 debug_printf ("Need step over [LWP %ld]? Cancelling, PC was changed. "
4758 "Old stop_pc was 0x%s, PC is now 0x%s\n",
d86d4aaf
DE
4759 lwpid_of (thread),
4760 paddress (lwp->stop_pc), paddress (pc));
d50171e4
PA
4761 return 0;
4762 }
4763
484b3c32
YQ
4764 /* On software single step target, resume the inferior with signal
4765 rather than stepping over. */
4766 if (can_software_single_step ()
4767 && lwp->pending_signals != NULL
4768 && lwp_signal_can_be_delivered (lwp))
4769 {
4770 if (debug_threads)
4771 debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
4772 " signals.\n",
4773 lwpid_of (thread));
4774
4775 return 0;
4776 }
4777
0bfdf32f
GB
4778 saved_thread = current_thread;
4779 current_thread = thread;
d50171e4 4780
8b07ae33 4781 /* We can only step over breakpoints we know about. */
fa593d66 4782 if (breakpoint_here (pc) || fast_tracepoint_jump_here (pc))
d50171e4 4783 {
8b07ae33 4784 /* Don't step over a breakpoint that GDB expects to hit
9f3a5c85
LM
4785 though. If the condition is being evaluated on the target's side
4786 and it evaluate to false, step over this breakpoint as well. */
4787 if (gdb_breakpoint_here (pc)
d3ce09f5
SS
4788 && gdb_condition_true_at_breakpoint (pc)
4789 && gdb_no_commands_at_breakpoint (pc))
8b07ae33
PA
4790 {
4791 if (debug_threads)
87ce2a04
DE
4792 debug_printf ("Need step over [LWP %ld]? yes, but found"
4793 " GDB breakpoint at 0x%s; skipping step over\n",
d86d4aaf 4794 lwpid_of (thread), paddress (pc));
d50171e4 4795
0bfdf32f 4796 current_thread = saved_thread;
8b07ae33
PA
4797 return 0;
4798 }
4799 else
4800 {
4801 if (debug_threads)
87ce2a04
DE
4802 debug_printf ("Need step over [LWP %ld]? yes, "
4803 "found breakpoint at 0x%s\n",
d86d4aaf 4804 lwpid_of (thread), paddress (pc));
d50171e4 4805
8b07ae33
PA
4806 /* We've found an lwp that needs stepping over --- return 1 so
4807 that find_inferior stops looking. */
0bfdf32f 4808 current_thread = saved_thread;
8b07ae33 4809
8b07ae33
PA
4810 return 1;
4811 }
d50171e4
PA
4812 }
4813
0bfdf32f 4814 current_thread = saved_thread;
d50171e4
PA
4815
4816 if (debug_threads)
87ce2a04
DE
4817 debug_printf ("Need step over [LWP %ld]? No, no breakpoint found"
4818 " at 0x%s\n",
d86d4aaf 4819 lwpid_of (thread), paddress (pc));
c6ecbae5 4820
bd99dc85 4821 return 0;
5544ad89
DJ
4822}
4823
d50171e4
PA
4824/* Start a step-over operation on LWP. When LWP stopped at a
4825 breakpoint, to make progress, we need to remove the breakpoint out
4826 of the way. If we let other threads run while we do that, they may
4827 pass by the breakpoint location and miss hitting it. To avoid
4828 that, a step-over momentarily stops all threads while LWP is
c40c8d4b
YQ
4829 single-stepped by either hardware or software while the breakpoint
4830 is temporarily uninserted from the inferior. When the single-step
4831 finishes, we reinsert the breakpoint, and let all threads that are
4832 supposed to be running, run again. */
d50171e4
PA
4833
4834static int
4835start_step_over (struct lwp_info *lwp)
4836{
d86d4aaf 4837 struct thread_info *thread = get_lwp_thread (lwp);
0bfdf32f 4838 struct thread_info *saved_thread;
d50171e4
PA
4839 CORE_ADDR pc;
4840 int step;
4841
4842 if (debug_threads)
87ce2a04 4843 debug_printf ("Starting step-over on LWP %ld. Stopping all threads\n",
d86d4aaf 4844 lwpid_of (thread));
d50171e4 4845
7984d532 4846 stop_all_lwps (1, lwp);
863d01bd
PA
4847
4848 if (lwp->suspended != 0)
4849 {
4850 internal_error (__FILE__, __LINE__,
4851 "LWP %ld suspended=%d\n", lwpid_of (thread),
4852 lwp->suspended);
4853 }
d50171e4
PA
4854
4855 if (debug_threads)
87ce2a04 4856 debug_printf ("Done stopping all threads for step-over.\n");
d50171e4
PA
4857
4858 /* Note, we should always reach here with an already adjusted PC,
4859 either by GDB (if we're resuming due to GDB's request), or by our
4860 caller, if we just finished handling an internal breakpoint GDB
4861 shouldn't care about. */
4862 pc = get_pc (lwp);
4863
0bfdf32f
GB
4864 saved_thread = current_thread;
4865 current_thread = thread;
d50171e4
PA
4866
4867 lwp->bp_reinsert = pc;
4868 uninsert_breakpoints_at (pc);
fa593d66 4869 uninsert_fast_tracepoint_jumps_at (pc);
d50171e4 4870
7fe5e27e 4871 step = single_step (lwp);
d50171e4 4872
0bfdf32f 4873 current_thread = saved_thread;
d50171e4
PA
4874
4875 linux_resume_one_lwp (lwp, step, 0, NULL);
4876
4877 /* Require next event from this LWP. */
d86d4aaf 4878 step_over_bkpt = thread->entry.id;
d50171e4
PA
4879 return 1;
4880}
4881
4882/* Finish a step-over. Reinsert the breakpoint we had uninserted in
4883 start_step_over, if still there, and delete any reinsert
4884 breakpoints we've set, on non hardware single-step targets. */
4885
4886static int
4887finish_step_over (struct lwp_info *lwp)
4888{
4889 if (lwp->bp_reinsert != 0)
4890 {
f79b145d
YQ
4891 struct thread_info *saved_thread = current_thread;
4892
d50171e4 4893 if (debug_threads)
87ce2a04 4894 debug_printf ("Finished step over.\n");
d50171e4 4895
f79b145d
YQ
4896 current_thread = get_lwp_thread (lwp);
4897
d50171e4
PA
4898 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
4899 may be no breakpoint to reinsert there by now. */
4900 reinsert_breakpoints_at (lwp->bp_reinsert);
fa593d66 4901 reinsert_fast_tracepoint_jumps_at (lwp->bp_reinsert);
d50171e4
PA
4902
4903 lwp->bp_reinsert = 0;
4904
4905 /* Delete any software-single-step reinsert breakpoints. No
4906 longer needed. We don't have to worry about other threads
4907 hitting this trap, and later not being able to explain it,
4908 because we were stepping over a breakpoint, and we hold all
4909 threads but LWP stopped while doing that. */
4910 if (!can_hardware_single_step ())
f79b145d 4911 {
bec903c9
YQ
4912 gdb_assert (has_reinsert_breakpoints (current_thread));
4913 delete_reinsert_breakpoints (current_thread);
f79b145d 4914 }
d50171e4
PA
4915
4916 step_over_bkpt = null_ptid;
f79b145d 4917 current_thread = saved_thread;
d50171e4
PA
4918 return 1;
4919 }
4920 else
4921 return 0;
4922}
4923
863d01bd
PA
4924/* If there's a step over in progress, wait until all threads stop
4925 (that is, until the stepping thread finishes its step), and
4926 unsuspend all lwps. The stepping thread ends with its status
4927 pending, which is processed later when we get back to processing
4928 events. */
4929
4930static void
4931complete_ongoing_step_over (void)
4932{
4933 if (!ptid_equal (step_over_bkpt, null_ptid))
4934 {
4935 struct lwp_info *lwp;
4936 int wstat;
4937 int ret;
4938
4939 if (debug_threads)
4940 debug_printf ("detach: step over in progress, finish it first\n");
4941
4942 /* Passing NULL_PTID as filter indicates we want all events to
4943 be left pending. Eventually this returns when there are no
4944 unwaited-for children left. */
4945 ret = linux_wait_for_event_filtered (minus_one_ptid, null_ptid,
4946 &wstat, __WALL);
4947 gdb_assert (ret == -1);
4948
4949 lwp = find_lwp_pid (step_over_bkpt);
4950 if (lwp != NULL)
4951 finish_step_over (lwp);
4952 step_over_bkpt = null_ptid;
4953 unsuspend_all_lwps (lwp);
4954 }
4955}
4956
5544ad89
DJ
4957/* This function is called once per thread. We check the thread's resume
4958 request, which will tell us whether to resume, step, or leave the thread
bd99dc85 4959 stopped; and what signal, if any, it should be sent.
5544ad89 4960
bd99dc85
PA
4961 For threads which we aren't explicitly told otherwise, we preserve
4962 the stepping flag; this is used for stepping over gdbserver-placed
4963 breakpoints.
4964
4965 If pending_flags was set in any thread, we queue any needed
4966 signals, since we won't actually resume. We already have a pending
4967 event to report, so we don't need to preserve any step requests;
4968 they should be re-issued if necessary. */
4969
4970static int
4971linux_resume_one_thread (struct inferior_list_entry *entry, void *arg)
5544ad89 4972{
d86d4aaf
DE
4973 struct thread_info *thread = (struct thread_info *) entry;
4974 struct lwp_info *lwp = get_thread_lwp (thread);
d50171e4
PA
4975 int leave_all_stopped = * (int *) arg;
4976 int leave_pending;
5544ad89 4977
2bd7c093 4978 if (lwp->resume == NULL)
bd99dc85 4979 return 0;
5544ad89 4980
bd99dc85 4981 if (lwp->resume->kind == resume_stop)
5544ad89 4982 {
bd99dc85 4983 if (debug_threads)
d86d4aaf 4984 debug_printf ("resume_stop request for LWP %ld\n", lwpid_of (thread));
bd99dc85
PA
4985
4986 if (!lwp->stopped)
4987 {
4988 if (debug_threads)
d86d4aaf 4989 debug_printf ("stopping LWP %ld\n", lwpid_of (thread));
bd99dc85 4990
d50171e4
PA
4991 /* Stop the thread, and wait for the event asynchronously,
4992 through the event loop. */
02fc4de7 4993 send_sigstop (lwp);
bd99dc85
PA
4994 }
4995 else
4996 {
4997 if (debug_threads)
87ce2a04 4998 debug_printf ("already stopped LWP %ld\n",
d86d4aaf 4999 lwpid_of (thread));
d50171e4
PA
5000
5001 /* The LWP may have been stopped in an internal event that
5002 was not meant to be notified back to GDB (e.g., gdbserver
5003 breakpoint), so we should be reporting a stop event in
5004 this case too. */
5005
5006 /* If the thread already has a pending SIGSTOP, this is a
5007 no-op. Otherwise, something later will presumably resume
5008 the thread and this will cause it to cancel any pending
5009 operation, due to last_resume_kind == resume_stop. If
5010 the thread already has a pending status to report, we
5011 will still report it the next time we wait - see
5012 status_pending_p_callback. */
1a981360
PA
5013
5014 /* If we already have a pending signal to report, then
5015 there's no need to queue a SIGSTOP, as this means we're
5016 midway through moving the LWP out of the jumppad, and we
5017 will report the pending signal as soon as that is
5018 finished. */
5019 if (lwp->pending_signals_to_report == NULL)
5020 send_sigstop (lwp);
bd99dc85 5021 }
32ca6d61 5022
bd99dc85
PA
5023 /* For stop requests, we're done. */
5024 lwp->resume = NULL;
fc7238bb 5025 thread->last_status.kind = TARGET_WAITKIND_IGNORE;
bd99dc85 5026 return 0;
5544ad89
DJ
5027 }
5028
bd99dc85 5029 /* If this thread which is about to be resumed has a pending status,
863d01bd
PA
5030 then don't resume it - we can just report the pending status.
5031 Likewise if it is suspended, because e.g., another thread is
5032 stepping past a breakpoint. Make sure to queue any signals that
5033 would otherwise be sent. In all-stop mode, we do this decision
5034 based on if *any* thread has a pending status. If there's a
5035 thread that needs the step-over-breakpoint dance, then don't
5036 resume any other thread but that particular one. */
5037 leave_pending = (lwp->suspended
5038 || lwp->status_pending_p
5039 || leave_all_stopped);
5544ad89 5040
0e9a339e
YQ
5041 /* If we have a new signal, enqueue the signal. */
5042 if (lwp->resume->sig != 0)
5043 {
5044 siginfo_t info, *info_p;
5045
5046 /* If this is the same signal we were previously stopped by,
5047 make sure to queue its siginfo. */
5048 if (WIFSTOPPED (lwp->last_status)
5049 && WSTOPSIG (lwp->last_status) == lwp->resume->sig
5050 && ptrace (PTRACE_GETSIGINFO, lwpid_of (thread),
5051 (PTRACE_TYPE_ARG3) 0, &info) == 0)
5052 info_p = &info;
5053 else
5054 info_p = NULL;
5055
5056 enqueue_pending_signal (lwp, lwp->resume->sig, info_p);
5057 }
5058
d50171e4 5059 if (!leave_pending)
bd99dc85
PA
5060 {
5061 if (debug_threads)
d86d4aaf 5062 debug_printf ("resuming LWP %ld\n", lwpid_of (thread));
5544ad89 5063
0e9a339e 5064 proceed_one_lwp (entry, NULL);
bd99dc85
PA
5065 }
5066 else
5067 {
5068 if (debug_threads)
d86d4aaf 5069 debug_printf ("leaving LWP %ld stopped\n", lwpid_of (thread));
bd99dc85 5070 }
5544ad89 5071
fc7238bb 5072 thread->last_status.kind = TARGET_WAITKIND_IGNORE;
bd99dc85 5073 lwp->resume = NULL;
5544ad89 5074 return 0;
0d62e5e8
DJ
5075}
5076
5077static void
2bd7c093 5078linux_resume (struct thread_resume *resume_info, size_t n)
0d62e5e8 5079{
2bd7c093 5080 struct thread_resume_array array = { resume_info, n };
d86d4aaf 5081 struct thread_info *need_step_over = NULL;
d50171e4
PA
5082 int any_pending;
5083 int leave_all_stopped;
c6ecbae5 5084
87ce2a04
DE
5085 if (debug_threads)
5086 {
5087 debug_enter ();
5088 debug_printf ("linux_resume:\n");
5089 }
5090
2bd7c093 5091 find_inferior (&all_threads, linux_set_resume_request, &array);
5544ad89 5092
d50171e4
PA
5093 /* If there is a thread which would otherwise be resumed, which has
5094 a pending status, then don't resume any threads - we can just
5095 report the pending status. Make sure to queue any signals that
5096 would otherwise be sent. In non-stop mode, we'll apply this
5097 logic to each thread individually. We consume all pending events
5098 before considering to start a step-over (in all-stop). */
5099 any_pending = 0;
bd99dc85 5100 if (!non_stop)
d86d4aaf 5101 find_inferior (&all_threads, resume_status_pending_p, &any_pending);
d50171e4
PA
5102
5103 /* If there is a thread which would otherwise be resumed, which is
5104 stopped at a breakpoint that needs stepping over, then don't
5105 resume any threads - have it step over the breakpoint with all
5106 other threads stopped, then resume all threads again. Make sure
5107 to queue any signals that would otherwise be delivered or
5108 queued. */
5109 if (!any_pending && supports_breakpoints ())
5110 need_step_over
d86d4aaf
DE
5111 = (struct thread_info *) find_inferior (&all_threads,
5112 need_step_over_p, NULL);
d50171e4
PA
5113
5114 leave_all_stopped = (need_step_over != NULL || any_pending);
5115
5116 if (debug_threads)
5117 {
5118 if (need_step_over != NULL)
87ce2a04 5119 debug_printf ("Not resuming all, need step over\n");
d50171e4 5120 else if (any_pending)
87ce2a04
DE
5121 debug_printf ("Not resuming, all-stop and found "
5122 "an LWP with pending status\n");
d50171e4 5123 else
87ce2a04 5124 debug_printf ("Resuming, no pending status or step over needed\n");
d50171e4
PA
5125 }
5126
5127 /* Even if we're leaving threads stopped, queue all signals we'd
5128 otherwise deliver. */
5129 find_inferior (&all_threads, linux_resume_one_thread, &leave_all_stopped);
5130
5131 if (need_step_over)
d86d4aaf 5132 start_step_over (get_thread_lwp (need_step_over));
87ce2a04
DE
5133
5134 if (debug_threads)
5135 {
5136 debug_printf ("linux_resume done\n");
5137 debug_exit ();
5138 }
1bebeeca
PA
5139
5140 /* We may have events that were pending that can/should be sent to
5141 the client now. Trigger a linux_wait call. */
5142 if (target_is_async_p ())
5143 async_file_mark ();
d50171e4
PA
5144}
5145
5146/* This function is called once per thread. We check the thread's
5147 last resume request, which will tell us whether to resume, step, or
5148 leave the thread stopped. Any signal the client requested to be
5149 delivered has already been enqueued at this point.
5150
5151 If any thread that GDB wants running is stopped at an internal
5152 breakpoint that needs stepping over, we start a step-over operation
5153 on that particular thread, and leave all others stopped. */
5154
7984d532
PA
5155static int
5156proceed_one_lwp (struct inferior_list_entry *entry, void *except)
d50171e4 5157{
d86d4aaf
DE
5158 struct thread_info *thread = (struct thread_info *) entry;
5159 struct lwp_info *lwp = get_thread_lwp (thread);
d50171e4
PA
5160 int step;
5161
7984d532
PA
5162 if (lwp == except)
5163 return 0;
d50171e4
PA
5164
5165 if (debug_threads)
d86d4aaf 5166 debug_printf ("proceed_one_lwp: lwp %ld\n", lwpid_of (thread));
d50171e4
PA
5167
5168 if (!lwp->stopped)
5169 {
5170 if (debug_threads)
d86d4aaf 5171 debug_printf (" LWP %ld already running\n", lwpid_of (thread));
7984d532 5172 return 0;
d50171e4
PA
5173 }
5174
02fc4de7
PA
5175 if (thread->last_resume_kind == resume_stop
5176 && thread->last_status.kind != TARGET_WAITKIND_IGNORE)
d50171e4
PA
5177 {
5178 if (debug_threads)
87ce2a04 5179 debug_printf (" client wants LWP to remain %ld stopped\n",
d86d4aaf 5180 lwpid_of (thread));
7984d532 5181 return 0;
d50171e4
PA
5182 }
5183
5184 if (lwp->status_pending_p)
5185 {
5186 if (debug_threads)
87ce2a04 5187 debug_printf (" LWP %ld has pending status, leaving stopped\n",
d86d4aaf 5188 lwpid_of (thread));
7984d532 5189 return 0;
d50171e4
PA
5190 }
5191
7984d532
PA
5192 gdb_assert (lwp->suspended >= 0);
5193
d50171e4
PA
5194 if (lwp->suspended)
5195 {
5196 if (debug_threads)
d86d4aaf 5197 debug_printf (" LWP %ld is suspended\n", lwpid_of (thread));
7984d532 5198 return 0;
d50171e4
PA
5199 }
5200
1a981360
PA
5201 if (thread->last_resume_kind == resume_stop
5202 && lwp->pending_signals_to_report == NULL
5203 && lwp->collecting_fast_tracepoint == 0)
02fc4de7
PA
5204 {
5205 /* We haven't reported this LWP as stopped yet (otherwise, the
5206 last_status.kind check above would catch it, and we wouldn't
5207 reach here. This LWP may have been momentarily paused by a
5208 stop_all_lwps call while handling for example, another LWP's
5209 step-over. In that case, the pending expected SIGSTOP signal
5210 that was queued at vCont;t handling time will have already
5211 been consumed by wait_for_sigstop, and so we need to requeue
5212 another one here. Note that if the LWP already has a SIGSTOP
5213 pending, this is a no-op. */
5214
5215 if (debug_threads)
87ce2a04
DE
5216 debug_printf ("Client wants LWP %ld to stop. "
5217 "Making sure it has a SIGSTOP pending\n",
d86d4aaf 5218 lwpid_of (thread));
02fc4de7
PA
5219
5220 send_sigstop (lwp);
5221 }
5222
863d01bd
PA
5223 if (thread->last_resume_kind == resume_step)
5224 {
5225 if (debug_threads)
5226 debug_printf (" stepping LWP %ld, client wants it stepping\n",
5227 lwpid_of (thread));
8901d193
YQ
5228
5229 /* If resume_step is requested by GDB, install reinsert
5230 breakpoints when the thread is about to be actually resumed if
5231 the reinsert breakpoints weren't removed. */
5232 if (can_software_single_step () && !has_reinsert_breakpoints (thread))
5233 install_software_single_step_breakpoints (lwp);
5234
5235 step = maybe_hw_step (thread);
863d01bd
PA
5236 }
5237 else if (lwp->bp_reinsert != 0)
5238 {
5239 if (debug_threads)
5240 debug_printf (" stepping LWP %ld, reinsert set\n",
5241 lwpid_of (thread));
f79b145d
YQ
5242
5243 step = maybe_hw_step (thread);
863d01bd
PA
5244 }
5245 else
5246 step = 0;
5247
d50171e4 5248 linux_resume_one_lwp (lwp, step, 0, NULL);
7984d532
PA
5249 return 0;
5250}
5251
5252static int
5253unsuspend_and_proceed_one_lwp (struct inferior_list_entry *entry, void *except)
5254{
d86d4aaf
DE
5255 struct thread_info *thread = (struct thread_info *) entry;
5256 struct lwp_info *lwp = get_thread_lwp (thread);
7984d532
PA
5257
5258 if (lwp == except)
5259 return 0;
5260
863d01bd 5261 lwp_suspended_decr (lwp);
7984d532
PA
5262
5263 return proceed_one_lwp (entry, except);
d50171e4
PA
5264}
5265
5266/* When we finish a step-over, set threads running again. If there's
5267 another thread that may need a step-over, now's the time to start
5268 it. Eventually, we'll move all threads past their breakpoints. */
5269
5270static void
5271proceed_all_lwps (void)
5272{
d86d4aaf 5273 struct thread_info *need_step_over;
d50171e4
PA
5274
5275 /* If there is a thread which would otherwise be resumed, which is
5276 stopped at a breakpoint that needs stepping over, then don't
5277 resume any threads - have it step over the breakpoint with all
5278 other threads stopped, then resume all threads again. */
5279
5280 if (supports_breakpoints ())
5281 {
5282 need_step_over
d86d4aaf
DE
5283 = (struct thread_info *) find_inferior (&all_threads,
5284 need_step_over_p, NULL);
d50171e4
PA
5285
5286 if (need_step_over != NULL)
5287 {
5288 if (debug_threads)
87ce2a04
DE
5289 debug_printf ("proceed_all_lwps: found "
5290 "thread %ld needing a step-over\n",
5291 lwpid_of (need_step_over));
d50171e4 5292
d86d4aaf 5293 start_step_over (get_thread_lwp (need_step_over));
d50171e4
PA
5294 return;
5295 }
5296 }
5544ad89 5297
d50171e4 5298 if (debug_threads)
87ce2a04 5299 debug_printf ("Proceeding, no step-over needed\n");
d50171e4 5300
d86d4aaf 5301 find_inferior (&all_threads, proceed_one_lwp, NULL);
d50171e4
PA
5302}
5303
5304/* Stopped LWPs that the client wanted to be running, that don't have
5305 pending statuses, are set to run again, except for EXCEPT, if not
5306 NULL. This undoes a stop_all_lwps call. */
5307
5308static void
7984d532 5309unstop_all_lwps (int unsuspend, struct lwp_info *except)
d50171e4 5310{
5544ad89
DJ
5311 if (debug_threads)
5312 {
87ce2a04 5313 debug_enter ();
d50171e4 5314 if (except)
87ce2a04 5315 debug_printf ("unstopping all lwps, except=(LWP %ld)\n",
d86d4aaf 5316 lwpid_of (get_lwp_thread (except)));
5544ad89 5317 else
87ce2a04 5318 debug_printf ("unstopping all lwps\n");
5544ad89
DJ
5319 }
5320
7984d532 5321 if (unsuspend)
d86d4aaf 5322 find_inferior (&all_threads, unsuspend_and_proceed_one_lwp, except);
7984d532 5323 else
d86d4aaf 5324 find_inferior (&all_threads, proceed_one_lwp, except);
87ce2a04
DE
5325
5326 if (debug_threads)
5327 {
5328 debug_printf ("unstop_all_lwps done\n");
5329 debug_exit ();
5330 }
0d62e5e8
DJ
5331}
5332
58caa3dc
DJ
5333
5334#ifdef HAVE_LINUX_REGSETS
5335
1faeff08
MR
5336#define use_linux_regsets 1
5337
030031ee
PA
5338/* Returns true if REGSET has been disabled. */
5339
5340static int
5341regset_disabled (struct regsets_info *info, struct regset_info *regset)
5342{
5343 return (info->disabled_regsets != NULL
5344 && info->disabled_regsets[regset - info->regsets]);
5345}
5346
5347/* Disable REGSET. */
5348
5349static void
5350disable_regset (struct regsets_info *info, struct regset_info *regset)
5351{
5352 int dr_offset;
5353
5354 dr_offset = regset - info->regsets;
5355 if (info->disabled_regsets == NULL)
224c3ddb 5356 info->disabled_regsets = (char *) xcalloc (1, info->num_regsets);
030031ee
PA
5357 info->disabled_regsets[dr_offset] = 1;
5358}
5359
58caa3dc 5360static int
3aee8918
PA
5361regsets_fetch_inferior_registers (struct regsets_info *regsets_info,
5362 struct regcache *regcache)
58caa3dc
DJ
5363{
5364 struct regset_info *regset;
e9d25b98 5365 int saw_general_regs = 0;
95954743 5366 int pid;
1570b33e 5367 struct iovec iov;
58caa3dc 5368
0bfdf32f 5369 pid = lwpid_of (current_thread);
28eef672 5370 for (regset = regsets_info->regsets; regset->size >= 0; regset++)
58caa3dc 5371 {
1570b33e
L
5372 void *buf, *data;
5373 int nt_type, res;
58caa3dc 5374
030031ee 5375 if (regset->size == 0 || regset_disabled (regsets_info, regset))
28eef672 5376 continue;
58caa3dc 5377
bca929d3 5378 buf = xmalloc (regset->size);
1570b33e
L
5379
5380 nt_type = regset->nt_type;
5381 if (nt_type)
5382 {
5383 iov.iov_base = buf;
5384 iov.iov_len = regset->size;
5385 data = (void *) &iov;
5386 }
5387 else
5388 data = buf;
5389
dfb64f85 5390#ifndef __sparc__
f15f9948 5391 res = ptrace (regset->get_request, pid,
b8e1b30e 5392 (PTRACE_TYPE_ARG3) (long) nt_type, data);
dfb64f85 5393#else
1570b33e 5394 res = ptrace (regset->get_request, pid, data, nt_type);
dfb64f85 5395#endif
58caa3dc
DJ
5396 if (res < 0)
5397 {
5398 if (errno == EIO)
5399 {
52fa2412 5400 /* If we get EIO on a regset, do not try it again for
3aee8918 5401 this process mode. */
030031ee 5402 disable_regset (regsets_info, regset);
58caa3dc 5403 }
e5a9158d
AA
5404 else if (errno == ENODATA)
5405 {
5406 /* ENODATA may be returned if the regset is currently
5407 not "active". This can happen in normal operation,
5408 so suppress the warning in this case. */
5409 }
fcd4a73d
YQ
5410 else if (errno == ESRCH)
5411 {
5412 /* At this point, ESRCH should mean the process is
5413 already gone, in which case we simply ignore attempts
5414 to read its registers. */
5415 }
58caa3dc
DJ
5416 else
5417 {
0d62e5e8 5418 char s[256];
95954743
PA
5419 sprintf (s, "ptrace(regsets_fetch_inferior_registers) PID=%d",
5420 pid);
0d62e5e8 5421 perror (s);
58caa3dc
DJ
5422 }
5423 }
098dbe61
AA
5424 else
5425 {
5426 if (regset->type == GENERAL_REGS)
5427 saw_general_regs = 1;
5428 regset->store_function (regcache, buf);
5429 }
fdeb2a12 5430 free (buf);
58caa3dc 5431 }
e9d25b98
DJ
5432 if (saw_general_regs)
5433 return 0;
5434 else
5435 return 1;
58caa3dc
DJ
5436}
5437
5438static int
3aee8918
PA
5439regsets_store_inferior_registers (struct regsets_info *regsets_info,
5440 struct regcache *regcache)
58caa3dc
DJ
5441{
5442 struct regset_info *regset;
e9d25b98 5443 int saw_general_regs = 0;
95954743 5444 int pid;
1570b33e 5445 struct iovec iov;
58caa3dc 5446
0bfdf32f 5447 pid = lwpid_of (current_thread);
28eef672 5448 for (regset = regsets_info->regsets; regset->size >= 0; regset++)
58caa3dc 5449 {
1570b33e
L
5450 void *buf, *data;
5451 int nt_type, res;
58caa3dc 5452
feea5f36
AA
5453 if (regset->size == 0 || regset_disabled (regsets_info, regset)
5454 || regset->fill_function == NULL)
28eef672 5455 continue;
58caa3dc 5456
bca929d3 5457 buf = xmalloc (regset->size);
545587ee
DJ
5458
5459 /* First fill the buffer with the current register set contents,
5460 in case there are any items in the kernel's regset that are
5461 not in gdbserver's regcache. */
1570b33e
L
5462
5463 nt_type = regset->nt_type;
5464 if (nt_type)
5465 {
5466 iov.iov_base = buf;
5467 iov.iov_len = regset->size;
5468 data = (void *) &iov;
5469 }
5470 else
5471 data = buf;
5472
dfb64f85 5473#ifndef __sparc__
f15f9948 5474 res = ptrace (regset->get_request, pid,
b8e1b30e 5475 (PTRACE_TYPE_ARG3) (long) nt_type, data);
dfb64f85 5476#else
689cc2ae 5477 res = ptrace (regset->get_request, pid, data, nt_type);
dfb64f85 5478#endif
545587ee
DJ
5479
5480 if (res == 0)
5481 {
5482 /* Then overlay our cached registers on that. */
442ea881 5483 regset->fill_function (regcache, buf);
545587ee
DJ
5484
5485 /* Only now do we write the register set. */
dfb64f85 5486#ifndef __sparc__
f15f9948 5487 res = ptrace (regset->set_request, pid,
b8e1b30e 5488 (PTRACE_TYPE_ARG3) (long) nt_type, data);
dfb64f85 5489#else
1570b33e 5490 res = ptrace (regset->set_request, pid, data, nt_type);
dfb64f85 5491#endif
545587ee
DJ
5492 }
5493
58caa3dc
DJ
5494 if (res < 0)
5495 {
5496 if (errno == EIO)
5497 {
52fa2412 5498 /* If we get EIO on a regset, do not try it again for
3aee8918 5499 this process mode. */
030031ee 5500 disable_regset (regsets_info, regset);
58caa3dc 5501 }
3221518c
UW
5502 else if (errno == ESRCH)
5503 {
1b3f6016
PA
5504 /* At this point, ESRCH should mean the process is
5505 already gone, in which case we simply ignore attempts
5506 to change its registers. See also the related
5507 comment in linux_resume_one_lwp. */
fdeb2a12 5508 free (buf);
3221518c
UW
5509 return 0;
5510 }
58caa3dc
DJ
5511 else
5512 {
ce3a066d 5513 perror ("Warning: ptrace(regsets_store_inferior_registers)");
58caa3dc
DJ
5514 }
5515 }
e9d25b98
DJ
5516 else if (regset->type == GENERAL_REGS)
5517 saw_general_regs = 1;
09ec9b38 5518 free (buf);
58caa3dc 5519 }
e9d25b98
DJ
5520 if (saw_general_regs)
5521 return 0;
5522 else
5523 return 1;
58caa3dc
DJ
5524}
5525
1faeff08 5526#else /* !HAVE_LINUX_REGSETS */
58caa3dc 5527
1faeff08 5528#define use_linux_regsets 0
3aee8918
PA
5529#define regsets_fetch_inferior_registers(regsets_info, regcache) 1
5530#define regsets_store_inferior_registers(regsets_info, regcache) 1
58caa3dc 5531
58caa3dc 5532#endif
1faeff08
MR
5533
5534/* Return 1 if register REGNO is supported by one of the regset ptrace
5535 calls or 0 if it has to be transferred individually. */
5536
5537static int
3aee8918 5538linux_register_in_regsets (const struct regs_info *regs_info, int regno)
1faeff08
MR
5539{
5540 unsigned char mask = 1 << (regno % 8);
5541 size_t index = regno / 8;
5542
5543 return (use_linux_regsets
3aee8918
PA
5544 && (regs_info->regset_bitmap == NULL
5545 || (regs_info->regset_bitmap[index] & mask) != 0));
1faeff08
MR
5546}
5547
58caa3dc 5548#ifdef HAVE_LINUX_USRREGS
1faeff08 5549
5b3da067 5550static int
3aee8918 5551register_addr (const struct usrregs_info *usrregs, int regnum)
1faeff08
MR
5552{
5553 int addr;
5554
3aee8918 5555 if (regnum < 0 || regnum >= usrregs->num_regs)
1faeff08
MR
5556 error ("Invalid register number %d.", regnum);
5557
3aee8918 5558 addr = usrregs->regmap[regnum];
1faeff08
MR
5559
5560 return addr;
5561}
5562
5563/* Fetch one register. */
5564static void
3aee8918
PA
5565fetch_register (const struct usrregs_info *usrregs,
5566 struct regcache *regcache, int regno)
1faeff08
MR
5567{
5568 CORE_ADDR regaddr;
5569 int i, size;
5570 char *buf;
5571 int pid;
5572
3aee8918 5573 if (regno >= usrregs->num_regs)
1faeff08
MR
5574 return;
5575 if ((*the_low_target.cannot_fetch_register) (regno))
5576 return;
5577
3aee8918 5578 regaddr = register_addr (usrregs, regno);
1faeff08
MR
5579 if (regaddr == -1)
5580 return;
5581
3aee8918
PA
5582 size = ((register_size (regcache->tdesc, regno)
5583 + sizeof (PTRACE_XFER_TYPE) - 1)
1faeff08 5584 & -sizeof (PTRACE_XFER_TYPE));
224c3ddb 5585 buf = (char *) alloca (size);
1faeff08 5586
0bfdf32f 5587 pid = lwpid_of (current_thread);
1faeff08
MR
5588 for (i = 0; i < size; i += sizeof (PTRACE_XFER_TYPE))
5589 {
5590 errno = 0;
5591 *(PTRACE_XFER_TYPE *) (buf + i) =
5592 ptrace (PTRACE_PEEKUSER, pid,
5593 /* Coerce to a uintptr_t first to avoid potential gcc warning
5594 of coercing an 8 byte integer to a 4 byte pointer. */
b8e1b30e 5595 (PTRACE_TYPE_ARG3) (uintptr_t) regaddr, (PTRACE_TYPE_ARG4) 0);
1faeff08
MR
5596 regaddr += sizeof (PTRACE_XFER_TYPE);
5597 if (errno != 0)
5598 error ("reading register %d: %s", regno, strerror (errno));
5599 }
5600
5601 if (the_low_target.supply_ptrace_register)
5602 the_low_target.supply_ptrace_register (regcache, regno, buf);
5603 else
5604 supply_register (regcache, regno, buf);
5605}
5606
5607/* Store one register. */
5608static void
3aee8918
PA
5609store_register (const struct usrregs_info *usrregs,
5610 struct regcache *regcache, int regno)
1faeff08
MR
5611{
5612 CORE_ADDR regaddr;
5613 int i, size;
5614 char *buf;
5615 int pid;
5616
3aee8918 5617 if (regno >= usrregs->num_regs)
1faeff08
MR
5618 return;
5619 if ((*the_low_target.cannot_store_register) (regno))
5620 return;
5621
3aee8918 5622 regaddr = register_addr (usrregs, regno);
1faeff08
MR
5623 if (regaddr == -1)
5624 return;
5625
3aee8918
PA
5626 size = ((register_size (regcache->tdesc, regno)
5627 + sizeof (PTRACE_XFER_TYPE) - 1)
1faeff08 5628 & -sizeof (PTRACE_XFER_TYPE));
224c3ddb 5629 buf = (char *) alloca (size);
1faeff08
MR
5630 memset (buf, 0, size);
5631
5632 if (the_low_target.collect_ptrace_register)
5633 the_low_target.collect_ptrace_register (regcache, regno, buf);
5634 else
5635 collect_register (regcache, regno, buf);
5636
0bfdf32f 5637 pid = lwpid_of (current_thread);
1faeff08
MR
5638 for (i = 0; i < size; i += sizeof (PTRACE_XFER_TYPE))
5639 {
5640 errno = 0;
5641 ptrace (PTRACE_POKEUSER, pid,
5642 /* Coerce to a uintptr_t first to avoid potential gcc warning
5643 about coercing an 8 byte integer to a 4 byte pointer. */
b8e1b30e
LM
5644 (PTRACE_TYPE_ARG3) (uintptr_t) regaddr,
5645 (PTRACE_TYPE_ARG4) *(PTRACE_XFER_TYPE *) (buf + i));
1faeff08
MR
5646 if (errno != 0)
5647 {
5648 /* At this point, ESRCH should mean the process is
5649 already gone, in which case we simply ignore attempts
5650 to change its registers. See also the related
5651 comment in linux_resume_one_lwp. */
5652 if (errno == ESRCH)
5653 return;
5654
5655 if ((*the_low_target.cannot_store_register) (regno) == 0)
5656 error ("writing register %d: %s", regno, strerror (errno));
5657 }
5658 regaddr += sizeof (PTRACE_XFER_TYPE);
5659 }
5660}
5661
5662/* Fetch all registers, or just one, from the child process.
5663 If REGNO is -1, do this for all registers, skipping any that are
5664 assumed to have been retrieved by regsets_fetch_inferior_registers,
5665 unless ALL is non-zero.
5666 Otherwise, REGNO specifies which register (so we can save time). */
5667static void
3aee8918
PA
5668usr_fetch_inferior_registers (const struct regs_info *regs_info,
5669 struct regcache *regcache, int regno, int all)
1faeff08 5670{
3aee8918
PA
5671 struct usrregs_info *usr = regs_info->usrregs;
5672
1faeff08
MR
5673 if (regno == -1)
5674 {
3aee8918
PA
5675 for (regno = 0; regno < usr->num_regs; regno++)
5676 if (all || !linux_register_in_regsets (regs_info, regno))
5677 fetch_register (usr, regcache, regno);
1faeff08
MR
5678 }
5679 else
3aee8918 5680 fetch_register (usr, regcache, regno);
1faeff08
MR
5681}
5682
5683/* Store our register values back into the inferior.
5684 If REGNO is -1, do this for all registers, skipping any that are
5685 assumed to have been saved by regsets_store_inferior_registers,
5686 unless ALL is non-zero.
5687 Otherwise, REGNO specifies which register (so we can save time). */
5688static void
3aee8918
PA
5689usr_store_inferior_registers (const struct regs_info *regs_info,
5690 struct regcache *regcache, int regno, int all)
1faeff08 5691{
3aee8918
PA
5692 struct usrregs_info *usr = regs_info->usrregs;
5693
1faeff08
MR
5694 if (regno == -1)
5695 {
3aee8918
PA
5696 for (regno = 0; regno < usr->num_regs; regno++)
5697 if (all || !linux_register_in_regsets (regs_info, regno))
5698 store_register (usr, regcache, regno);
1faeff08
MR
5699 }
5700 else
3aee8918 5701 store_register (usr, regcache, regno);
1faeff08
MR
5702}
5703
5704#else /* !HAVE_LINUX_USRREGS */
5705
3aee8918
PA
5706#define usr_fetch_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
5707#define usr_store_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
1faeff08 5708
58caa3dc 5709#endif
1faeff08
MR
5710
5711
5b3da067 5712static void
1faeff08
MR
5713linux_fetch_registers (struct regcache *regcache, int regno)
5714{
5715 int use_regsets;
5716 int all = 0;
3aee8918 5717 const struct regs_info *regs_info = (*the_low_target.regs_info) ();
1faeff08
MR
5718
5719 if (regno == -1)
5720 {
3aee8918
PA
5721 if (the_low_target.fetch_register != NULL
5722 && regs_info->usrregs != NULL)
5723 for (regno = 0; regno < regs_info->usrregs->num_regs; regno++)
c14dfd32
PA
5724 (*the_low_target.fetch_register) (regcache, regno);
5725
3aee8918
PA
5726 all = regsets_fetch_inferior_registers (regs_info->regsets_info, regcache);
5727 if (regs_info->usrregs != NULL)
5728 usr_fetch_inferior_registers (regs_info, regcache, -1, all);
1faeff08
MR
5729 }
5730 else
5731 {
c14dfd32
PA
5732 if (the_low_target.fetch_register != NULL
5733 && (*the_low_target.fetch_register) (regcache, regno))
5734 return;
5735
3aee8918 5736 use_regsets = linux_register_in_regsets (regs_info, regno);
1faeff08 5737 if (use_regsets)
3aee8918
PA
5738 all = regsets_fetch_inferior_registers (regs_info->regsets_info,
5739 regcache);
5740 if ((!use_regsets || all) && regs_info->usrregs != NULL)
5741 usr_fetch_inferior_registers (regs_info, regcache, regno, 1);
1faeff08 5742 }
58caa3dc
DJ
5743}
5744
5b3da067 5745static void
442ea881 5746linux_store_registers (struct regcache *regcache, int regno)
58caa3dc 5747{
1faeff08
MR
5748 int use_regsets;
5749 int all = 0;
3aee8918 5750 const struct regs_info *regs_info = (*the_low_target.regs_info) ();
1faeff08
MR
5751
5752 if (regno == -1)
5753 {
3aee8918
PA
5754 all = regsets_store_inferior_registers (regs_info->regsets_info,
5755 regcache);
5756 if (regs_info->usrregs != NULL)
5757 usr_store_inferior_registers (regs_info, regcache, regno, all);
1faeff08
MR
5758 }
5759 else
5760 {
3aee8918 5761 use_regsets = linux_register_in_regsets (regs_info, regno);
1faeff08 5762 if (use_regsets)
3aee8918
PA
5763 all = regsets_store_inferior_registers (regs_info->regsets_info,
5764 regcache);
5765 if ((!use_regsets || all) && regs_info->usrregs != NULL)
5766 usr_store_inferior_registers (regs_info, regcache, regno, 1);
1faeff08 5767 }
58caa3dc
DJ
5768}
5769
da6d8c04 5770
da6d8c04
DJ
5771/* Copy LEN bytes from inferior's memory starting at MEMADDR
5772 to debugger memory starting at MYADDR. */
5773
c3e735a6 5774static int
f450004a 5775linux_read_memory (CORE_ADDR memaddr, unsigned char *myaddr, int len)
da6d8c04 5776{
0bfdf32f 5777 int pid = lwpid_of (current_thread);
4934b29e
MR
5778 register PTRACE_XFER_TYPE *buffer;
5779 register CORE_ADDR addr;
5780 register int count;
5781 char filename[64];
da6d8c04 5782 register int i;
4934b29e 5783 int ret;
fd462a61 5784 int fd;
fd462a61
DJ
5785
5786 /* Try using /proc. Don't bother for one word. */
5787 if (len >= 3 * sizeof (long))
5788 {
4934b29e
MR
5789 int bytes;
5790
fd462a61
DJ
5791 /* We could keep this file open and cache it - possibly one per
5792 thread. That requires some juggling, but is even faster. */
95954743 5793 sprintf (filename, "/proc/%d/mem", pid);
fd462a61
DJ
5794 fd = open (filename, O_RDONLY | O_LARGEFILE);
5795 if (fd == -1)
5796 goto no_proc;
5797
5798 /* If pread64 is available, use it. It's faster if the kernel
5799 supports it (only one syscall), and it's 64-bit safe even on
5800 32-bit platforms (for instance, SPARC debugging a SPARC64
5801 application). */
5802#ifdef HAVE_PREAD64
4934b29e 5803 bytes = pread64 (fd, myaddr, len, memaddr);
fd462a61 5804#else
4934b29e
MR
5805 bytes = -1;
5806 if (lseek (fd, memaddr, SEEK_SET) != -1)
5807 bytes = read (fd, myaddr, len);
fd462a61 5808#endif
fd462a61
DJ
5809
5810 close (fd);
4934b29e
MR
5811 if (bytes == len)
5812 return 0;
5813
5814 /* Some data was read, we'll try to get the rest with ptrace. */
5815 if (bytes > 0)
5816 {
5817 memaddr += bytes;
5818 myaddr += bytes;
5819 len -= bytes;
5820 }
fd462a61 5821 }
da6d8c04 5822
fd462a61 5823 no_proc:
4934b29e
MR
5824 /* Round starting address down to longword boundary. */
5825 addr = memaddr & -(CORE_ADDR) sizeof (PTRACE_XFER_TYPE);
5826 /* Round ending address up; get number of longwords that makes. */
5827 count = ((((memaddr + len) - addr) + sizeof (PTRACE_XFER_TYPE) - 1)
5828 / sizeof (PTRACE_XFER_TYPE));
5829 /* Allocate buffer of that many longwords. */
8d749320 5830 buffer = XALLOCAVEC (PTRACE_XFER_TYPE, count);
4934b29e 5831
da6d8c04 5832 /* Read all the longwords */
4934b29e 5833 errno = 0;
da6d8c04
DJ
5834 for (i = 0; i < count; i++, addr += sizeof (PTRACE_XFER_TYPE))
5835 {
14ce3065
DE
5836 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5837 about coercing an 8 byte integer to a 4 byte pointer. */
5838 buffer[i] = ptrace (PTRACE_PEEKTEXT, pid,
b8e1b30e
LM
5839 (PTRACE_TYPE_ARG3) (uintptr_t) addr,
5840 (PTRACE_TYPE_ARG4) 0);
c3e735a6 5841 if (errno)
4934b29e 5842 break;
da6d8c04 5843 }
4934b29e 5844 ret = errno;
da6d8c04
DJ
5845
5846 /* Copy appropriate bytes out of the buffer. */
8d409d16
MR
5847 if (i > 0)
5848 {
5849 i *= sizeof (PTRACE_XFER_TYPE);
5850 i -= memaddr & (sizeof (PTRACE_XFER_TYPE) - 1);
5851 memcpy (myaddr,
5852 (char *) buffer + (memaddr & (sizeof (PTRACE_XFER_TYPE) - 1)),
5853 i < len ? i : len);
5854 }
c3e735a6 5855
4934b29e 5856 return ret;
da6d8c04
DJ
5857}
5858
93ae6fdc
PA
5859/* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
5860 memory at MEMADDR. On failure (cannot write to the inferior)
f0ae6fc3 5861 returns the value of errno. Always succeeds if LEN is zero. */
da6d8c04 5862
ce3a066d 5863static int
f450004a 5864linux_write_memory (CORE_ADDR memaddr, const unsigned char *myaddr, int len)
da6d8c04
DJ
5865{
5866 register int i;
5867 /* Round starting address down to longword boundary. */
5868 register CORE_ADDR addr = memaddr & -(CORE_ADDR) sizeof (PTRACE_XFER_TYPE);
5869 /* Round ending address up; get number of longwords that makes. */
5870 register int count
493e2a69
MS
5871 = (((memaddr + len) - addr) + sizeof (PTRACE_XFER_TYPE) - 1)
5872 / sizeof (PTRACE_XFER_TYPE);
5873
da6d8c04 5874 /* Allocate buffer of that many longwords. */
8d749320 5875 register PTRACE_XFER_TYPE *buffer = XALLOCAVEC (PTRACE_XFER_TYPE, count);
493e2a69 5876
0bfdf32f 5877 int pid = lwpid_of (current_thread);
da6d8c04 5878
f0ae6fc3
PA
5879 if (len == 0)
5880 {
5881 /* Zero length write always succeeds. */
5882 return 0;
5883 }
5884
0d62e5e8
DJ
5885 if (debug_threads)
5886 {
58d6951d 5887 /* Dump up to four bytes. */
bf47e248
PA
5888 char str[4 * 2 + 1];
5889 char *p = str;
5890 int dump = len < 4 ? len : 4;
5891
5892 for (i = 0; i < dump; i++)
5893 {
5894 sprintf (p, "%02x", myaddr[i]);
5895 p += 2;
5896 }
5897 *p = '\0';
5898
5899 debug_printf ("Writing %s to 0x%08lx in process %d\n",
5900 str, (long) memaddr, pid);
0d62e5e8
DJ
5901 }
5902
da6d8c04
DJ
5903 /* Fill start and end extra bytes of buffer with existing memory data. */
5904
93ae6fdc 5905 errno = 0;
14ce3065
DE
5906 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
5907 about coercing an 8 byte integer to a 4 byte pointer. */
5908 buffer[0] = ptrace (PTRACE_PEEKTEXT, pid,
b8e1b30e
LM
5909 (PTRACE_TYPE_ARG3) (uintptr_t) addr,
5910 (PTRACE_TYPE_ARG4) 0);
93ae6fdc
PA
5911 if (errno)
5912 return errno;
da6d8c04
DJ
5913
5914 if (count > 1)
5915 {
93ae6fdc 5916 errno = 0;
da6d8c04 5917 buffer[count - 1]
95954743 5918 = ptrace (PTRACE_PEEKTEXT, pid,
14ce3065
DE
5919 /* Coerce to a uintptr_t first to avoid potential gcc warning
5920 about coercing an 8 byte integer to a 4 byte pointer. */
b8e1b30e 5921 (PTRACE_TYPE_ARG3) (uintptr_t) (addr + (count - 1)
14ce3065 5922 * sizeof (PTRACE_XFER_TYPE)),
b8e1b30e 5923 (PTRACE_TYPE_ARG4) 0);
93ae6fdc
PA
5924 if (errno)
5925 return errno;
da6d8c04
DJ
5926 }
5927
93ae6fdc 5928 /* Copy data to be written over corresponding part of buffer. */
da6d8c04 5929
493e2a69
MS
5930 memcpy ((char *) buffer + (memaddr & (sizeof (PTRACE_XFER_TYPE) - 1)),
5931 myaddr, len);
da6d8c04
DJ
5932
5933 /* Write the entire buffer. */
5934
5935 for (i = 0; i < count; i++, addr += sizeof (PTRACE_XFER_TYPE))
5936 {
5937 errno = 0;
14ce3065
DE
5938 ptrace (PTRACE_POKETEXT, pid,
5939 /* Coerce to a uintptr_t first to avoid potential gcc warning
5940 about coercing an 8 byte integer to a 4 byte pointer. */
b8e1b30e
LM
5941 (PTRACE_TYPE_ARG3) (uintptr_t) addr,
5942 (PTRACE_TYPE_ARG4) buffer[i]);
da6d8c04
DJ
5943 if (errno)
5944 return errno;
5945 }
5946
5947 return 0;
5948}
2f2893d9
DJ
5949
5950static void
5951linux_look_up_symbols (void)
5952{
0d62e5e8 5953#ifdef USE_THREAD_DB
95954743
PA
5954 struct process_info *proc = current_process ();
5955
fe978cb0 5956 if (proc->priv->thread_db != NULL)
0d62e5e8
DJ
5957 return;
5958
9b4c5f87 5959 thread_db_init ();
0d62e5e8
DJ
5960#endif
5961}
5962
e5379b03 5963static void
ef57601b 5964linux_request_interrupt (void)
e5379b03 5965{
a1928bad 5966 extern unsigned long signal_pid;
e5379b03 5967
78708b7c
PA
5968 /* Send a SIGINT to the process group. This acts just like the user
5969 typed a ^C on the controlling terminal. */
5970 kill (-signal_pid, SIGINT);
e5379b03
DJ
5971}
5972
aa691b87
RM
5973/* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
5974 to debugger memory starting at MYADDR. */
5975
5976static int
f450004a 5977linux_read_auxv (CORE_ADDR offset, unsigned char *myaddr, unsigned int len)
aa691b87
RM
5978{
5979 char filename[PATH_MAX];
5980 int fd, n;
0bfdf32f 5981 int pid = lwpid_of (current_thread);
aa691b87 5982
6cebaf6e 5983 xsnprintf (filename, sizeof filename, "/proc/%d/auxv", pid);
aa691b87
RM
5984
5985 fd = open (filename, O_RDONLY);
5986 if (fd < 0)
5987 return -1;
5988
5989 if (offset != (CORE_ADDR) 0
5990 && lseek (fd, (off_t) offset, SEEK_SET) != (off_t) offset)
5991 n = -1;
5992 else
5993 n = read (fd, myaddr, len);
5994
5995 close (fd);
5996
5997 return n;
5998}
5999
d993e290
PA
6000/* These breakpoint and watchpoint related wrapper functions simply
6001 pass on the function call if the target has registered a
6002 corresponding function. */
e013ee27
OF
6003
6004static int
802e8e6d
PA
6005linux_supports_z_point_type (char z_type)
6006{
6007 return (the_low_target.supports_z_point_type != NULL
6008 && the_low_target.supports_z_point_type (z_type));
6009}
6010
6011static int
6012linux_insert_point (enum raw_bkpt_type type, CORE_ADDR addr,
6013 int size, struct raw_breakpoint *bp)
e013ee27 6014{
c8f4bfdd
YQ
6015 if (type == raw_bkpt_type_sw)
6016 return insert_memory_breakpoint (bp);
6017 else if (the_low_target.insert_point != NULL)
802e8e6d 6018 return the_low_target.insert_point (type, addr, size, bp);
e013ee27
OF
6019 else
6020 /* Unsupported (see target.h). */
6021 return 1;
6022}
6023
6024static int
802e8e6d
PA
6025linux_remove_point (enum raw_bkpt_type type, CORE_ADDR addr,
6026 int size, struct raw_breakpoint *bp)
e013ee27 6027{
c8f4bfdd
YQ
6028 if (type == raw_bkpt_type_sw)
6029 return remove_memory_breakpoint (bp);
6030 else if (the_low_target.remove_point != NULL)
802e8e6d 6031 return the_low_target.remove_point (type, addr, size, bp);
e013ee27
OF
6032 else
6033 /* Unsupported (see target.h). */
6034 return 1;
6035}
6036
3e572f71
PA
6037/* Implement the to_stopped_by_sw_breakpoint target_ops
6038 method. */
6039
6040static int
6041linux_stopped_by_sw_breakpoint (void)
6042{
6043 struct lwp_info *lwp = get_thread_lwp (current_thread);
6044
6045 return (lwp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT);
6046}
6047
6048/* Implement the to_supports_stopped_by_sw_breakpoint target_ops
6049 method. */
6050
6051static int
6052linux_supports_stopped_by_sw_breakpoint (void)
6053{
6054 return USE_SIGTRAP_SIGINFO;
6055}
6056
6057/* Implement the to_stopped_by_hw_breakpoint target_ops
6058 method. */
6059
6060static int
6061linux_stopped_by_hw_breakpoint (void)
6062{
6063 struct lwp_info *lwp = get_thread_lwp (current_thread);
6064
6065 return (lwp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT);
6066}
6067
6068/* Implement the to_supports_stopped_by_hw_breakpoint target_ops
6069 method. */
6070
6071static int
6072linux_supports_stopped_by_hw_breakpoint (void)
6073{
6074 return USE_SIGTRAP_SIGINFO;
6075}
6076
70b90b91 6077/* Implement the supports_hardware_single_step target_ops method. */
45614f15
YQ
6078
6079static int
70b90b91 6080linux_supports_hardware_single_step (void)
45614f15 6081{
45614f15
YQ
6082 return can_hardware_single_step ();
6083}
6084
7d00775e
AT
6085static int
6086linux_supports_software_single_step (void)
6087{
6088 return can_software_single_step ();
6089}
6090
e013ee27
OF
6091static int
6092linux_stopped_by_watchpoint (void)
6093{
0bfdf32f 6094 struct lwp_info *lwp = get_thread_lwp (current_thread);
c3adc08c 6095
15c66dd6 6096 return lwp->stop_reason == TARGET_STOPPED_BY_WATCHPOINT;
e013ee27
OF
6097}
6098
6099static CORE_ADDR
6100linux_stopped_data_address (void)
6101{
0bfdf32f 6102 struct lwp_info *lwp = get_thread_lwp (current_thread);
c3adc08c
PA
6103
6104 return lwp->stopped_data_address;
e013ee27
OF
6105}
6106
db0dfaa0
LM
6107#if defined(__UCLIBC__) && defined(HAS_NOMMU) \
6108 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
6109 && defined(PT_TEXT_END_ADDR)
6110
6111/* This is only used for targets that define PT_TEXT_ADDR,
6112 PT_DATA_ADDR and PT_TEXT_END_ADDR. If those are not defined, supposedly
6113 the target has different ways of acquiring this information, like
6114 loadmaps. */
52fb6437
NS
6115
6116/* Under uClinux, programs are loaded at non-zero offsets, which we need
6117 to tell gdb about. */
6118
6119static int
6120linux_read_offsets (CORE_ADDR *text_p, CORE_ADDR *data_p)
6121{
52fb6437 6122 unsigned long text, text_end, data;
62828379 6123 int pid = lwpid_of (current_thread);
52fb6437
NS
6124
6125 errno = 0;
6126
b8e1b30e
LM
6127 text = ptrace (PTRACE_PEEKUSER, pid, (PTRACE_TYPE_ARG3) PT_TEXT_ADDR,
6128 (PTRACE_TYPE_ARG4) 0);
6129 text_end = ptrace (PTRACE_PEEKUSER, pid, (PTRACE_TYPE_ARG3) PT_TEXT_END_ADDR,
6130 (PTRACE_TYPE_ARG4) 0);
6131 data = ptrace (PTRACE_PEEKUSER, pid, (PTRACE_TYPE_ARG3) PT_DATA_ADDR,
6132 (PTRACE_TYPE_ARG4) 0);
52fb6437
NS
6133
6134 if (errno == 0)
6135 {
6136 /* Both text and data offsets produced at compile-time (and so
1b3f6016
PA
6137 used by gdb) are relative to the beginning of the program,
6138 with the data segment immediately following the text segment.
6139 However, the actual runtime layout in memory may put the data
6140 somewhere else, so when we send gdb a data base-address, we
6141 use the real data base address and subtract the compile-time
6142 data base-address from it (which is just the length of the
6143 text segment). BSS immediately follows data in both
6144 cases. */
52fb6437
NS
6145 *text_p = text;
6146 *data_p = data - (text_end - text);
1b3f6016 6147
52fb6437
NS
6148 return 1;
6149 }
52fb6437
NS
6150 return 0;
6151}
6152#endif
6153
07e059b5
VP
6154static int
6155linux_qxfer_osdata (const char *annex,
1b3f6016
PA
6156 unsigned char *readbuf, unsigned const char *writebuf,
6157 CORE_ADDR offset, int len)
07e059b5 6158{
d26e3629 6159 return linux_common_xfer_osdata (annex, readbuf, offset, len);
07e059b5
VP
6160}
6161
d0722149
DE
6162/* Convert a native/host siginfo object, into/from the siginfo in the
6163 layout of the inferiors' architecture. */
6164
6165static void
8adce034 6166siginfo_fixup (siginfo_t *siginfo, gdb_byte *inf_siginfo, int direction)
d0722149
DE
6167{
6168 int done = 0;
6169
6170 if (the_low_target.siginfo_fixup != NULL)
6171 done = the_low_target.siginfo_fixup (siginfo, inf_siginfo, direction);
6172
6173 /* If there was no callback, or the callback didn't do anything,
6174 then just do a straight memcpy. */
6175 if (!done)
6176 {
6177 if (direction == 1)
a5362b9a 6178 memcpy (siginfo, inf_siginfo, sizeof (siginfo_t));
d0722149 6179 else
a5362b9a 6180 memcpy (inf_siginfo, siginfo, sizeof (siginfo_t));
d0722149
DE
6181 }
6182}
6183
4aa995e1
PA
6184static int
6185linux_xfer_siginfo (const char *annex, unsigned char *readbuf,
6186 unsigned const char *writebuf, CORE_ADDR offset, int len)
6187{
d0722149 6188 int pid;
a5362b9a 6189 siginfo_t siginfo;
8adce034 6190 gdb_byte inf_siginfo[sizeof (siginfo_t)];
4aa995e1 6191
0bfdf32f 6192 if (current_thread == NULL)
4aa995e1
PA
6193 return -1;
6194
0bfdf32f 6195 pid = lwpid_of (current_thread);
4aa995e1
PA
6196
6197 if (debug_threads)
87ce2a04
DE
6198 debug_printf ("%s siginfo for lwp %d.\n",
6199 readbuf != NULL ? "Reading" : "Writing",
6200 pid);
4aa995e1 6201
0adea5f7 6202 if (offset >= sizeof (siginfo))
4aa995e1
PA
6203 return -1;
6204
b8e1b30e 6205 if (ptrace (PTRACE_GETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo) != 0)
4aa995e1
PA
6206 return -1;
6207
d0722149
DE
6208 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
6209 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
6210 inferior with a 64-bit GDBSERVER should look the same as debugging it
6211 with a 32-bit GDBSERVER, we need to convert it. */
6212 siginfo_fixup (&siginfo, inf_siginfo, 0);
6213
4aa995e1
PA
6214 if (offset + len > sizeof (siginfo))
6215 len = sizeof (siginfo) - offset;
6216
6217 if (readbuf != NULL)
d0722149 6218 memcpy (readbuf, inf_siginfo + offset, len);
4aa995e1
PA
6219 else
6220 {
d0722149
DE
6221 memcpy (inf_siginfo + offset, writebuf, len);
6222
6223 /* Convert back to ptrace layout before flushing it out. */
6224 siginfo_fixup (&siginfo, inf_siginfo, 1);
6225
b8e1b30e 6226 if (ptrace (PTRACE_SETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo) != 0)
4aa995e1
PA
6227 return -1;
6228 }
6229
6230 return len;
6231}
6232
bd99dc85
PA
6233/* SIGCHLD handler that serves two purposes: In non-stop/async mode,
6234 so we notice when children change state; as the handler for the
6235 sigsuspend in my_waitpid. */
6236
6237static void
6238sigchld_handler (int signo)
6239{
6240 int old_errno = errno;
6241
6242 if (debug_threads)
e581f2b4
PA
6243 {
6244 do
6245 {
6246 /* fprintf is not async-signal-safe, so call write
6247 directly. */
6248 if (write (2, "sigchld_handler\n",
6249 sizeof ("sigchld_handler\n") - 1) < 0)
6250 break; /* just ignore */
6251 } while (0);
6252 }
bd99dc85
PA
6253
6254 if (target_is_async_p ())
6255 async_file_mark (); /* trigger a linux_wait */
6256
6257 errno = old_errno;
6258}
6259
6260static int
6261linux_supports_non_stop (void)
6262{
6263 return 1;
6264}
6265
6266static int
6267linux_async (int enable)
6268{
7089dca4 6269 int previous = target_is_async_p ();
bd99dc85 6270
8336d594 6271 if (debug_threads)
87ce2a04
DE
6272 debug_printf ("linux_async (%d), previous=%d\n",
6273 enable, previous);
8336d594 6274
bd99dc85
PA
6275 if (previous != enable)
6276 {
6277 sigset_t mask;
6278 sigemptyset (&mask);
6279 sigaddset (&mask, SIGCHLD);
6280
6281 sigprocmask (SIG_BLOCK, &mask, NULL);
6282
6283 if (enable)
6284 {
6285 if (pipe (linux_event_pipe) == -1)
aa96c426
GB
6286 {
6287 linux_event_pipe[0] = -1;
6288 linux_event_pipe[1] = -1;
6289 sigprocmask (SIG_UNBLOCK, &mask, NULL);
6290
6291 warning ("creating event pipe failed.");
6292 return previous;
6293 }
bd99dc85
PA
6294
6295 fcntl (linux_event_pipe[0], F_SETFL, O_NONBLOCK);
6296 fcntl (linux_event_pipe[1], F_SETFL, O_NONBLOCK);
6297
6298 /* Register the event loop handler. */
6299 add_file_handler (linux_event_pipe[0],
6300 handle_target_event, NULL);
6301
6302 /* Always trigger a linux_wait. */
6303 async_file_mark ();
6304 }
6305 else
6306 {
6307 delete_file_handler (linux_event_pipe[0]);
6308
6309 close (linux_event_pipe[0]);
6310 close (linux_event_pipe[1]);
6311 linux_event_pipe[0] = -1;
6312 linux_event_pipe[1] = -1;
6313 }
6314
6315 sigprocmask (SIG_UNBLOCK, &mask, NULL);
6316 }
6317
6318 return previous;
6319}
6320
6321static int
6322linux_start_non_stop (int nonstop)
6323{
6324 /* Register or unregister from event-loop accordingly. */
6325 linux_async (nonstop);
aa96c426
GB
6326
6327 if (target_is_async_p () != (nonstop != 0))
6328 return -1;
6329
bd99dc85
PA
6330 return 0;
6331}
6332
cf8fd78b
PA
6333static int
6334linux_supports_multi_process (void)
6335{
6336 return 1;
6337}
6338
89245bc0
DB
6339/* Check if fork events are supported. */
6340
6341static int
6342linux_supports_fork_events (void)
6343{
6344 return linux_supports_tracefork ();
6345}
6346
6347/* Check if vfork events are supported. */
6348
6349static int
6350linux_supports_vfork_events (void)
6351{
6352 return linux_supports_tracefork ();
6353}
6354
94585166
DB
6355/* Check if exec events are supported. */
6356
6357static int
6358linux_supports_exec_events (void)
6359{
6360 return linux_supports_traceexec ();
6361}
6362
de0d863e
DB
6363/* Callback for 'find_inferior'. Set the (possibly changed) ptrace
6364 options for the specified lwp. */
6365
6366static int
6367reset_lwp_ptrace_options_callback (struct inferior_list_entry *entry,
6368 void *args)
6369{
6370 struct thread_info *thread = (struct thread_info *) entry;
6371 struct lwp_info *lwp = get_thread_lwp (thread);
6372
6373 if (!lwp->stopped)
6374 {
6375 /* Stop the lwp so we can modify its ptrace options. */
6376 lwp->must_set_ptrace_flags = 1;
6377 linux_stop_lwp (lwp);
6378 }
6379 else
6380 {
6381 /* Already stopped; go ahead and set the ptrace options. */
6382 struct process_info *proc = find_process_pid (pid_of (thread));
6383 int options = linux_low_ptrace_options (proc->attached);
6384
6385 linux_enable_event_reporting (lwpid_of (thread), options);
6386 lwp->must_set_ptrace_flags = 0;
6387 }
6388
6389 return 0;
6390}
6391
6392/* Target hook for 'handle_new_gdb_connection'. Causes a reset of the
6393 ptrace flags for all inferiors. This is in case the new GDB connection
6394 doesn't support the same set of events that the previous one did. */
6395
6396static void
6397linux_handle_new_gdb_connection (void)
6398{
6399 pid_t pid;
6400
6401 /* Request that all the lwps reset their ptrace options. */
6402 find_inferior (&all_threads, reset_lwp_ptrace_options_callback , &pid);
6403}
6404
03583c20
UW
6405static int
6406linux_supports_disable_randomization (void)
6407{
6408#ifdef HAVE_PERSONALITY
6409 return 1;
6410#else
6411 return 0;
6412#endif
6413}
efcbbd14 6414
d1feda86
YQ
6415static int
6416linux_supports_agent (void)
6417{
6418 return 1;
6419}
6420
c2d6af84
PA
6421static int
6422linux_supports_range_stepping (void)
6423{
6424 if (*the_low_target.supports_range_stepping == NULL)
6425 return 0;
6426
6427 return (*the_low_target.supports_range_stepping) ();
6428}
6429
efcbbd14
UW
6430/* Enumerate spufs IDs for process PID. */
6431static int
6432spu_enumerate_spu_ids (long pid, unsigned char *buf, CORE_ADDR offset, int len)
6433{
6434 int pos = 0;
6435 int written = 0;
6436 char path[128];
6437 DIR *dir;
6438 struct dirent *entry;
6439
6440 sprintf (path, "/proc/%ld/fd", pid);
6441 dir = opendir (path);
6442 if (!dir)
6443 return -1;
6444
6445 rewinddir (dir);
6446 while ((entry = readdir (dir)) != NULL)
6447 {
6448 struct stat st;
6449 struct statfs stfs;
6450 int fd;
6451
6452 fd = atoi (entry->d_name);
6453 if (!fd)
6454 continue;
6455
6456 sprintf (path, "/proc/%ld/fd/%d", pid, fd);
6457 if (stat (path, &st) != 0)
6458 continue;
6459 if (!S_ISDIR (st.st_mode))
6460 continue;
6461
6462 if (statfs (path, &stfs) != 0)
6463 continue;
6464 if (stfs.f_type != SPUFS_MAGIC)
6465 continue;
6466
6467 if (pos >= offset && pos + 4 <= offset + len)
6468 {
6469 *(unsigned int *)(buf + pos - offset) = fd;
6470 written += 4;
6471 }
6472 pos += 4;
6473 }
6474
6475 closedir (dir);
6476 return written;
6477}
6478
6479/* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
6480 object type, using the /proc file system. */
6481static int
6482linux_qxfer_spu (const char *annex, unsigned char *readbuf,
6483 unsigned const char *writebuf,
6484 CORE_ADDR offset, int len)
6485{
0bfdf32f 6486 long pid = lwpid_of (current_thread);
efcbbd14
UW
6487 char buf[128];
6488 int fd = 0;
6489 int ret = 0;
6490
6491 if (!writebuf && !readbuf)
6492 return -1;
6493
6494 if (!*annex)
6495 {
6496 if (!readbuf)
6497 return -1;
6498 else
6499 return spu_enumerate_spu_ids (pid, readbuf, offset, len);
6500 }
6501
6502 sprintf (buf, "/proc/%ld/fd/%s", pid, annex);
6503 fd = open (buf, writebuf? O_WRONLY : O_RDONLY);
6504 if (fd <= 0)
6505 return -1;
6506
6507 if (offset != 0
6508 && lseek (fd, (off_t) offset, SEEK_SET) != (off_t) offset)
6509 {
6510 close (fd);
6511 return 0;
6512 }
6513
6514 if (writebuf)
6515 ret = write (fd, writebuf, (size_t) len);
6516 else
6517 ret = read (fd, readbuf, (size_t) len);
6518
6519 close (fd);
6520 return ret;
6521}
6522
723b724b 6523#if defined PT_GETDSBT || defined PTRACE_GETFDPIC
78d85199
YQ
6524struct target_loadseg
6525{
6526 /* Core address to which the segment is mapped. */
6527 Elf32_Addr addr;
6528 /* VMA recorded in the program header. */
6529 Elf32_Addr p_vaddr;
6530 /* Size of this segment in memory. */
6531 Elf32_Word p_memsz;
6532};
6533
723b724b 6534# if defined PT_GETDSBT
78d85199
YQ
6535struct target_loadmap
6536{
6537 /* Protocol version number, must be zero. */
6538 Elf32_Word version;
6539 /* Pointer to the DSBT table, its size, and the DSBT index. */
6540 unsigned *dsbt_table;
6541 unsigned dsbt_size, dsbt_index;
6542 /* Number of segments in this map. */
6543 Elf32_Word nsegs;
6544 /* The actual memory map. */
6545 struct target_loadseg segs[/*nsegs*/];
6546};
723b724b
MF
6547# define LINUX_LOADMAP PT_GETDSBT
6548# define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
6549# define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
6550# else
6551struct target_loadmap
6552{
6553 /* Protocol version number, must be zero. */
6554 Elf32_Half version;
6555 /* Number of segments in this map. */
6556 Elf32_Half nsegs;
6557 /* The actual memory map. */
6558 struct target_loadseg segs[/*nsegs*/];
6559};
6560# define LINUX_LOADMAP PTRACE_GETFDPIC
6561# define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
6562# define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
6563# endif
78d85199 6564
78d85199
YQ
6565static int
6566linux_read_loadmap (const char *annex, CORE_ADDR offset,
6567 unsigned char *myaddr, unsigned int len)
6568{
0bfdf32f 6569 int pid = lwpid_of (current_thread);
78d85199
YQ
6570 int addr = -1;
6571 struct target_loadmap *data = NULL;
6572 unsigned int actual_length, copy_length;
6573
6574 if (strcmp (annex, "exec") == 0)
723b724b 6575 addr = (int) LINUX_LOADMAP_EXEC;
78d85199 6576 else if (strcmp (annex, "interp") == 0)
723b724b 6577 addr = (int) LINUX_LOADMAP_INTERP;
78d85199
YQ
6578 else
6579 return -1;
6580
723b724b 6581 if (ptrace (LINUX_LOADMAP, pid, addr, &data) != 0)
78d85199
YQ
6582 return -1;
6583
6584 if (data == NULL)
6585 return -1;
6586
6587 actual_length = sizeof (struct target_loadmap)
6588 + sizeof (struct target_loadseg) * data->nsegs;
6589
6590 if (offset < 0 || offset > actual_length)
6591 return -1;
6592
6593 copy_length = actual_length - offset < len ? actual_length - offset : len;
6594 memcpy (myaddr, (char *) data + offset, copy_length);
6595 return copy_length;
6596}
723b724b
MF
6597#else
6598# define linux_read_loadmap NULL
6599#endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
78d85199 6600
1570b33e 6601static void
06e03fff 6602linux_process_qsupported (char **features, int count)
1570b33e
L
6603{
6604 if (the_low_target.process_qsupported != NULL)
06e03fff 6605 the_low_target.process_qsupported (features, count);
1570b33e
L
6606}
6607
82075af2
JS
6608static int
6609linux_supports_catch_syscall (void)
6610{
6611 return (the_low_target.get_syscall_trapinfo != NULL
6612 && linux_supports_tracesysgood ());
6613}
6614
ae91f625
MK
6615static int
6616linux_get_ipa_tdesc_idx (void)
6617{
6618 if (the_low_target.get_ipa_tdesc_idx == NULL)
6619 return 0;
6620
6621 return (*the_low_target.get_ipa_tdesc_idx) ();
6622}
6623
219f2f23
PA
6624static int
6625linux_supports_tracepoints (void)
6626{
6627 if (*the_low_target.supports_tracepoints == NULL)
6628 return 0;
6629
6630 return (*the_low_target.supports_tracepoints) ();
6631}
6632
6633static CORE_ADDR
6634linux_read_pc (struct regcache *regcache)
6635{
6636 if (the_low_target.get_pc == NULL)
6637 return 0;
6638
6639 return (*the_low_target.get_pc) (regcache);
6640}
6641
6642static void
6643linux_write_pc (struct regcache *regcache, CORE_ADDR pc)
6644{
6645 gdb_assert (the_low_target.set_pc != NULL);
6646
6647 (*the_low_target.set_pc) (regcache, pc);
6648}
6649
8336d594
PA
6650static int
6651linux_thread_stopped (struct thread_info *thread)
6652{
6653 return get_thread_lwp (thread)->stopped;
6654}
6655
6656/* This exposes stop-all-threads functionality to other modules. */
6657
6658static void
7984d532 6659linux_pause_all (int freeze)
8336d594 6660{
7984d532
PA
6661 stop_all_lwps (freeze, NULL);
6662}
6663
6664/* This exposes unstop-all-threads functionality to other gdbserver
6665 modules. */
6666
6667static void
6668linux_unpause_all (int unfreeze)
6669{
6670 unstop_all_lwps (unfreeze, NULL);
8336d594
PA
6671}
6672
90d74c30
PA
6673static int
6674linux_prepare_to_access_memory (void)
6675{
6676 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6677 running LWP. */
6678 if (non_stop)
6679 linux_pause_all (1);
6680 return 0;
6681}
6682
6683static void
0146f85b 6684linux_done_accessing_memory (void)
90d74c30
PA
6685{
6686 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
6687 running LWP. */
6688 if (non_stop)
6689 linux_unpause_all (1);
6690}
6691
fa593d66
PA
6692static int
6693linux_install_fast_tracepoint_jump_pad (CORE_ADDR tpoint, CORE_ADDR tpaddr,
6694 CORE_ADDR collector,
6695 CORE_ADDR lockaddr,
6696 ULONGEST orig_size,
6697 CORE_ADDR *jump_entry,
405f8e94
SS
6698 CORE_ADDR *trampoline,
6699 ULONGEST *trampoline_size,
fa593d66
PA
6700 unsigned char *jjump_pad_insn,
6701 ULONGEST *jjump_pad_insn_size,
6702 CORE_ADDR *adjusted_insn_addr,
405f8e94
SS
6703 CORE_ADDR *adjusted_insn_addr_end,
6704 char *err)
fa593d66
PA
6705{
6706 return (*the_low_target.install_fast_tracepoint_jump_pad)
6707 (tpoint, tpaddr, collector, lockaddr, orig_size,
405f8e94
SS
6708 jump_entry, trampoline, trampoline_size,
6709 jjump_pad_insn, jjump_pad_insn_size,
6710 adjusted_insn_addr, adjusted_insn_addr_end,
6711 err);
fa593d66
PA
6712}
6713
6a271cae
PA
6714static struct emit_ops *
6715linux_emit_ops (void)
6716{
6717 if (the_low_target.emit_ops != NULL)
6718 return (*the_low_target.emit_ops) ();
6719 else
6720 return NULL;
6721}
6722
405f8e94
SS
6723static int
6724linux_get_min_fast_tracepoint_insn_len (void)
6725{
6726 return (*the_low_target.get_min_fast_tracepoint_insn_len) ();
6727}
6728
2268b414
JK
6729/* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
6730
6731static int
6732get_phdr_phnum_from_proc_auxv (const int pid, const int is_elf64,
6733 CORE_ADDR *phdr_memaddr, int *num_phdr)
6734{
6735 char filename[PATH_MAX];
6736 int fd;
6737 const int auxv_size = is_elf64
6738 ? sizeof (Elf64_auxv_t) : sizeof (Elf32_auxv_t);
6739 char buf[sizeof (Elf64_auxv_t)]; /* The larger of the two. */
6740
6741 xsnprintf (filename, sizeof filename, "/proc/%d/auxv", pid);
6742
6743 fd = open (filename, O_RDONLY);
6744 if (fd < 0)
6745 return 1;
6746
6747 *phdr_memaddr = 0;
6748 *num_phdr = 0;
6749 while (read (fd, buf, auxv_size) == auxv_size
6750 && (*phdr_memaddr == 0 || *num_phdr == 0))
6751 {
6752 if (is_elf64)
6753 {
6754 Elf64_auxv_t *const aux = (Elf64_auxv_t *) buf;
6755
6756 switch (aux->a_type)
6757 {
6758 case AT_PHDR:
6759 *phdr_memaddr = aux->a_un.a_val;
6760 break;
6761 case AT_PHNUM:
6762 *num_phdr = aux->a_un.a_val;
6763 break;
6764 }
6765 }
6766 else
6767 {
6768 Elf32_auxv_t *const aux = (Elf32_auxv_t *) buf;
6769
6770 switch (aux->a_type)
6771 {
6772 case AT_PHDR:
6773 *phdr_memaddr = aux->a_un.a_val;
6774 break;
6775 case AT_PHNUM:
6776 *num_phdr = aux->a_un.a_val;
6777 break;
6778 }
6779 }
6780 }
6781
6782 close (fd);
6783
6784 if (*phdr_memaddr == 0 || *num_phdr == 0)
6785 {
6786 warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
6787 "phdr_memaddr = %ld, phdr_num = %d",
6788 (long) *phdr_memaddr, *num_phdr);
6789 return 2;
6790 }
6791
6792 return 0;
6793}
6794
6795/* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
6796
6797static CORE_ADDR
6798get_dynamic (const int pid, const int is_elf64)
6799{
6800 CORE_ADDR phdr_memaddr, relocation;
db1ff28b 6801 int num_phdr, i;
2268b414 6802 unsigned char *phdr_buf;
db1ff28b 6803 const int phdr_size = is_elf64 ? sizeof (Elf64_Phdr) : sizeof (Elf32_Phdr);
2268b414
JK
6804
6805 if (get_phdr_phnum_from_proc_auxv (pid, is_elf64, &phdr_memaddr, &num_phdr))
6806 return 0;
6807
6808 gdb_assert (num_phdr < 100); /* Basic sanity check. */
224c3ddb 6809 phdr_buf = (unsigned char *) alloca (num_phdr * phdr_size);
2268b414
JK
6810
6811 if (linux_read_memory (phdr_memaddr, phdr_buf, num_phdr * phdr_size))
6812 return 0;
6813
6814 /* Compute relocation: it is expected to be 0 for "regular" executables,
6815 non-zero for PIE ones. */
6816 relocation = -1;
db1ff28b
JK
6817 for (i = 0; relocation == -1 && i < num_phdr; i++)
6818 if (is_elf64)
6819 {
6820 Elf64_Phdr *const p = (Elf64_Phdr *) (phdr_buf + i * phdr_size);
6821
6822 if (p->p_type == PT_PHDR)
6823 relocation = phdr_memaddr - p->p_vaddr;
6824 }
6825 else
6826 {
6827 Elf32_Phdr *const p = (Elf32_Phdr *) (phdr_buf + i * phdr_size);
6828
6829 if (p->p_type == PT_PHDR)
6830 relocation = phdr_memaddr - p->p_vaddr;
6831 }
6832
2268b414
JK
6833 if (relocation == -1)
6834 {
e237a7e2
JK
6835 /* PT_PHDR is optional, but necessary for PIE in general. Fortunately
6836 any real world executables, including PIE executables, have always
6837 PT_PHDR present. PT_PHDR is not present in some shared libraries or
6838 in fpc (Free Pascal 2.4) binaries but neither of those have a need for
6839 or present DT_DEBUG anyway (fpc binaries are statically linked).
6840
6841 Therefore if there exists DT_DEBUG there is always also PT_PHDR.
6842
6843 GDB could find RELOCATION also from AT_ENTRY - e_entry. */
6844
2268b414
JK
6845 return 0;
6846 }
6847
db1ff28b
JK
6848 for (i = 0; i < num_phdr; i++)
6849 {
6850 if (is_elf64)
6851 {
6852 Elf64_Phdr *const p = (Elf64_Phdr *) (phdr_buf + i * phdr_size);
6853
6854 if (p->p_type == PT_DYNAMIC)
6855 return p->p_vaddr + relocation;
6856 }
6857 else
6858 {
6859 Elf32_Phdr *const p = (Elf32_Phdr *) (phdr_buf + i * phdr_size);
2268b414 6860
db1ff28b
JK
6861 if (p->p_type == PT_DYNAMIC)
6862 return p->p_vaddr + relocation;
6863 }
6864 }
2268b414
JK
6865
6866 return 0;
6867}
6868
6869/* Return &_r_debug in the inferior, or -1 if not present. Return value
367ba2c2
MR
6870 can be 0 if the inferior does not yet have the library list initialized.
6871 We look for DT_MIPS_RLD_MAP first. MIPS executables use this instead of
6872 DT_DEBUG, although they sometimes contain an unused DT_DEBUG entry too. */
2268b414
JK
6873
6874static CORE_ADDR
6875get_r_debug (const int pid, const int is_elf64)
6876{
6877 CORE_ADDR dynamic_memaddr;
6878 const int dyn_size = is_elf64 ? sizeof (Elf64_Dyn) : sizeof (Elf32_Dyn);
6879 unsigned char buf[sizeof (Elf64_Dyn)]; /* The larger of the two. */
367ba2c2 6880 CORE_ADDR map = -1;
2268b414
JK
6881
6882 dynamic_memaddr = get_dynamic (pid, is_elf64);
6883 if (dynamic_memaddr == 0)
367ba2c2 6884 return map;
2268b414
JK
6885
6886 while (linux_read_memory (dynamic_memaddr, buf, dyn_size) == 0)
6887 {
6888 if (is_elf64)
6889 {
6890 Elf64_Dyn *const dyn = (Elf64_Dyn *) buf;
a738da3a 6891#if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
367ba2c2
MR
6892 union
6893 {
6894 Elf64_Xword map;
6895 unsigned char buf[sizeof (Elf64_Xword)];
6896 }
6897 rld_map;
a738da3a
MF
6898#endif
6899#ifdef DT_MIPS_RLD_MAP
367ba2c2
MR
6900 if (dyn->d_tag == DT_MIPS_RLD_MAP)
6901 {
6902 if (linux_read_memory (dyn->d_un.d_val,
6903 rld_map.buf, sizeof (rld_map.buf)) == 0)
6904 return rld_map.map;
6905 else
6906 break;
6907 }
75f62ce7 6908#endif /* DT_MIPS_RLD_MAP */
a738da3a
MF
6909#ifdef DT_MIPS_RLD_MAP_REL
6910 if (dyn->d_tag == DT_MIPS_RLD_MAP_REL)
6911 {
6912 if (linux_read_memory (dyn->d_un.d_val + dynamic_memaddr,
6913 rld_map.buf, sizeof (rld_map.buf)) == 0)
6914 return rld_map.map;
6915 else
6916 break;
6917 }
6918#endif /* DT_MIPS_RLD_MAP_REL */
2268b414 6919
367ba2c2
MR
6920 if (dyn->d_tag == DT_DEBUG && map == -1)
6921 map = dyn->d_un.d_val;
2268b414
JK
6922
6923 if (dyn->d_tag == DT_NULL)
6924 break;
6925 }
6926 else
6927 {
6928 Elf32_Dyn *const dyn = (Elf32_Dyn *) buf;
a738da3a 6929#if defined DT_MIPS_RLD_MAP || defined DT_MIPS_RLD_MAP_REL
367ba2c2
MR
6930 union
6931 {
6932 Elf32_Word map;
6933 unsigned char buf[sizeof (Elf32_Word)];
6934 }
6935 rld_map;
a738da3a
MF
6936#endif
6937#ifdef DT_MIPS_RLD_MAP
367ba2c2
MR
6938 if (dyn->d_tag == DT_MIPS_RLD_MAP)
6939 {
6940 if (linux_read_memory (dyn->d_un.d_val,
6941 rld_map.buf, sizeof (rld_map.buf)) == 0)
6942 return rld_map.map;
6943 else
6944 break;
6945 }
75f62ce7 6946#endif /* DT_MIPS_RLD_MAP */
a738da3a
MF
6947#ifdef DT_MIPS_RLD_MAP_REL
6948 if (dyn->d_tag == DT_MIPS_RLD_MAP_REL)
6949 {
6950 if (linux_read_memory (dyn->d_un.d_val + dynamic_memaddr,
6951 rld_map.buf, sizeof (rld_map.buf)) == 0)
6952 return rld_map.map;
6953 else
6954 break;
6955 }
6956#endif /* DT_MIPS_RLD_MAP_REL */
2268b414 6957
367ba2c2
MR
6958 if (dyn->d_tag == DT_DEBUG && map == -1)
6959 map = dyn->d_un.d_val;
2268b414
JK
6960
6961 if (dyn->d_tag == DT_NULL)
6962 break;
6963 }
6964
6965 dynamic_memaddr += dyn_size;
6966 }
6967
367ba2c2 6968 return map;
2268b414
JK
6969}
6970
6971/* Read one pointer from MEMADDR in the inferior. */
6972
6973static int
6974read_one_ptr (CORE_ADDR memaddr, CORE_ADDR *ptr, int ptr_size)
6975{
485f1ee4
PA
6976 int ret;
6977
6978 /* Go through a union so this works on either big or little endian
6979 hosts, when the inferior's pointer size is smaller than the size
6980 of CORE_ADDR. It is assumed the inferior's endianness is the
6981 same of the superior's. */
6982 union
6983 {
6984 CORE_ADDR core_addr;
6985 unsigned int ui;
6986 unsigned char uc;
6987 } addr;
6988
6989 ret = linux_read_memory (memaddr, &addr.uc, ptr_size);
6990 if (ret == 0)
6991 {
6992 if (ptr_size == sizeof (CORE_ADDR))
6993 *ptr = addr.core_addr;
6994 else if (ptr_size == sizeof (unsigned int))
6995 *ptr = addr.ui;
6996 else
6997 gdb_assert_not_reached ("unhandled pointer size");
6998 }
6999 return ret;
2268b414
JK
7000}
7001
7002struct link_map_offsets
7003 {
7004 /* Offset and size of r_debug.r_version. */
7005 int r_version_offset;
7006
7007 /* Offset and size of r_debug.r_map. */
7008 int r_map_offset;
7009
7010 /* Offset to l_addr field in struct link_map. */
7011 int l_addr_offset;
7012
7013 /* Offset to l_name field in struct link_map. */
7014 int l_name_offset;
7015
7016 /* Offset to l_ld field in struct link_map. */
7017 int l_ld_offset;
7018
7019 /* Offset to l_next field in struct link_map. */
7020 int l_next_offset;
7021
7022 /* Offset to l_prev field in struct link_map. */
7023 int l_prev_offset;
7024 };
7025
fb723180 7026/* Construct qXfer:libraries-svr4:read reply. */
2268b414
JK
7027
7028static int
7029linux_qxfer_libraries_svr4 (const char *annex, unsigned char *readbuf,
7030 unsigned const char *writebuf,
7031 CORE_ADDR offset, int len)
7032{
7033 char *document;
7034 unsigned document_len;
fe978cb0 7035 struct process_info_private *const priv = current_process ()->priv;
2268b414
JK
7036 char filename[PATH_MAX];
7037 int pid, is_elf64;
7038
7039 static const struct link_map_offsets lmo_32bit_offsets =
7040 {
7041 0, /* r_version offset. */
7042 4, /* r_debug.r_map offset. */
7043 0, /* l_addr offset in link_map. */
7044 4, /* l_name offset in link_map. */
7045 8, /* l_ld offset in link_map. */
7046 12, /* l_next offset in link_map. */
7047 16 /* l_prev offset in link_map. */
7048 };
7049
7050 static const struct link_map_offsets lmo_64bit_offsets =
7051 {
7052 0, /* r_version offset. */
7053 8, /* r_debug.r_map offset. */
7054 0, /* l_addr offset in link_map. */
7055 8, /* l_name offset in link_map. */
7056 16, /* l_ld offset in link_map. */
7057 24, /* l_next offset in link_map. */
7058 32 /* l_prev offset in link_map. */
7059 };
7060 const struct link_map_offsets *lmo;
214d508e 7061 unsigned int machine;
b1fbec62
GB
7062 int ptr_size;
7063 CORE_ADDR lm_addr = 0, lm_prev = 0;
7064 int allocated = 1024;
7065 char *p;
7066 CORE_ADDR l_name, l_addr, l_ld, l_next, l_prev;
7067 int header_done = 0;
2268b414
JK
7068
7069 if (writebuf != NULL)
7070 return -2;
7071 if (readbuf == NULL)
7072 return -1;
7073
0bfdf32f 7074 pid = lwpid_of (current_thread);
2268b414 7075 xsnprintf (filename, sizeof filename, "/proc/%d/exe", pid);
214d508e 7076 is_elf64 = elf_64_file_p (filename, &machine);
2268b414 7077 lmo = is_elf64 ? &lmo_64bit_offsets : &lmo_32bit_offsets;
b1fbec62 7078 ptr_size = is_elf64 ? 8 : 4;
2268b414 7079
b1fbec62
GB
7080 while (annex[0] != '\0')
7081 {
7082 const char *sep;
7083 CORE_ADDR *addrp;
7084 int len;
2268b414 7085
b1fbec62
GB
7086 sep = strchr (annex, '=');
7087 if (sep == NULL)
7088 break;
0c5bf5a9 7089
b1fbec62 7090 len = sep - annex;
61012eef 7091 if (len == 5 && startswith (annex, "start"))
b1fbec62 7092 addrp = &lm_addr;
61012eef 7093 else if (len == 4 && startswith (annex, "prev"))
b1fbec62
GB
7094 addrp = &lm_prev;
7095 else
7096 {
7097 annex = strchr (sep, ';');
7098 if (annex == NULL)
7099 break;
7100 annex++;
7101 continue;
7102 }
7103
7104 annex = decode_address_to_semicolon (addrp, sep + 1);
2268b414 7105 }
b1fbec62
GB
7106
7107 if (lm_addr == 0)
2268b414 7108 {
b1fbec62
GB
7109 int r_version = 0;
7110
7111 if (priv->r_debug == 0)
7112 priv->r_debug = get_r_debug (pid, is_elf64);
7113
7114 /* We failed to find DT_DEBUG. Such situation will not change
7115 for this inferior - do not retry it. Report it to GDB as
7116 E01, see for the reasons at the GDB solib-svr4.c side. */
7117 if (priv->r_debug == (CORE_ADDR) -1)
7118 return -1;
7119
7120 if (priv->r_debug != 0)
2268b414 7121 {
b1fbec62
GB
7122 if (linux_read_memory (priv->r_debug + lmo->r_version_offset,
7123 (unsigned char *) &r_version,
7124 sizeof (r_version)) != 0
7125 || r_version != 1)
7126 {
7127 warning ("unexpected r_debug version %d", r_version);
7128 }
7129 else if (read_one_ptr (priv->r_debug + lmo->r_map_offset,
7130 &lm_addr, ptr_size) != 0)
7131 {
7132 warning ("unable to read r_map from 0x%lx",
7133 (long) priv->r_debug + lmo->r_map_offset);
7134 }
2268b414 7135 }
b1fbec62 7136 }
2268b414 7137
224c3ddb 7138 document = (char *) xmalloc (allocated);
b1fbec62
GB
7139 strcpy (document, "<library-list-svr4 version=\"1.0\"");
7140 p = document + strlen (document);
7141
7142 while (lm_addr
7143 && read_one_ptr (lm_addr + lmo->l_name_offset,
7144 &l_name, ptr_size) == 0
7145 && read_one_ptr (lm_addr + lmo->l_addr_offset,
7146 &l_addr, ptr_size) == 0
7147 && read_one_ptr (lm_addr + lmo->l_ld_offset,
7148 &l_ld, ptr_size) == 0
7149 && read_one_ptr (lm_addr + lmo->l_prev_offset,
7150 &l_prev, ptr_size) == 0
7151 && read_one_ptr (lm_addr + lmo->l_next_offset,
7152 &l_next, ptr_size) == 0)
7153 {
7154 unsigned char libname[PATH_MAX];
7155
7156 if (lm_prev != l_prev)
2268b414 7157 {
b1fbec62
GB
7158 warning ("Corrupted shared library list: 0x%lx != 0x%lx",
7159 (long) lm_prev, (long) l_prev);
7160 break;
2268b414
JK
7161 }
7162
d878444c
JK
7163 /* Ignore the first entry even if it has valid name as the first entry
7164 corresponds to the main executable. The first entry should not be
7165 skipped if the dynamic loader was loaded late by a static executable
7166 (see solib-svr4.c parameter ignore_first). But in such case the main
7167 executable does not have PT_DYNAMIC present and this function already
7168 exited above due to failed get_r_debug. */
7169 if (lm_prev == 0)
2268b414 7170 {
d878444c
JK
7171 sprintf (p, " main-lm=\"0x%lx\"", (unsigned long) lm_addr);
7172 p = p + strlen (p);
7173 }
7174 else
7175 {
7176 /* Not checking for error because reading may stop before
7177 we've got PATH_MAX worth of characters. */
7178 libname[0] = '\0';
7179 linux_read_memory (l_name, libname, sizeof (libname) - 1);
7180 libname[sizeof (libname) - 1] = '\0';
7181 if (libname[0] != '\0')
2268b414 7182 {
d878444c
JK
7183 /* 6x the size for xml_escape_text below. */
7184 size_t len = 6 * strlen ((char *) libname);
7185 char *name;
2268b414 7186
d878444c
JK
7187 if (!header_done)
7188 {
7189 /* Terminate `<library-list-svr4'. */
7190 *p++ = '>';
7191 header_done = 1;
7192 }
2268b414 7193
db1ff28b 7194 while (allocated < p - document + len + 200)
d878444c
JK
7195 {
7196 /* Expand to guarantee sufficient storage. */
7197 uintptr_t document_len = p - document;
2268b414 7198
224c3ddb 7199 document = (char *) xrealloc (document, 2 * allocated);
d878444c
JK
7200 allocated *= 2;
7201 p = document + document_len;
7202 }
7203
7204 name = xml_escape_text ((char *) libname);
7205 p += sprintf (p, "<library name=\"%s\" lm=\"0x%lx\" "
db1ff28b 7206 "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
d878444c
JK
7207 name, (unsigned long) lm_addr,
7208 (unsigned long) l_addr, (unsigned long) l_ld);
7209 free (name);
7210 }
0afae3cf 7211 }
b1fbec62
GB
7212
7213 lm_prev = lm_addr;
7214 lm_addr = l_next;
2268b414
JK
7215 }
7216
b1fbec62
GB
7217 if (!header_done)
7218 {
7219 /* Empty list; terminate `<library-list-svr4'. */
7220 strcpy (p, "/>");
7221 }
7222 else
7223 strcpy (p, "</library-list-svr4>");
7224
2268b414
JK
7225 document_len = strlen (document);
7226 if (offset < document_len)
7227 document_len -= offset;
7228 else
7229 document_len = 0;
7230 if (len > document_len)
7231 len = document_len;
7232
7233 memcpy (readbuf, document + offset, len);
7234 xfree (document);
7235
7236 return len;
7237}
7238
9accd112
MM
7239#ifdef HAVE_LINUX_BTRACE
7240
969c39fb 7241/* See to_disable_btrace target method. */
9accd112 7242
969c39fb
MM
7243static int
7244linux_low_disable_btrace (struct btrace_target_info *tinfo)
7245{
7246 enum btrace_error err;
7247
7248 err = linux_disable_btrace (tinfo);
7249 return (err == BTRACE_ERR_NONE ? 0 : -1);
7250}
7251
bc504a31 7252/* Encode an Intel Processor Trace configuration. */
b20a6524
MM
7253
7254static void
7255linux_low_encode_pt_config (struct buffer *buffer,
7256 const struct btrace_data_pt_config *config)
7257{
7258 buffer_grow_str (buffer, "<pt-config>\n");
7259
7260 switch (config->cpu.vendor)
7261 {
7262 case CV_INTEL:
7263 buffer_xml_printf (buffer, "<cpu vendor=\"GenuineIntel\" family=\"%u\" "
7264 "model=\"%u\" stepping=\"%u\"/>\n",
7265 config->cpu.family, config->cpu.model,
7266 config->cpu.stepping);
7267 break;
7268
7269 default:
7270 break;
7271 }
7272
7273 buffer_grow_str (buffer, "</pt-config>\n");
7274}
7275
7276/* Encode a raw buffer. */
7277
7278static void
7279linux_low_encode_raw (struct buffer *buffer, const gdb_byte *data,
7280 unsigned int size)
7281{
7282 if (size == 0)
7283 return;
7284
7285 /* We use hex encoding - see common/rsp-low.h. */
7286 buffer_grow_str (buffer, "<raw>\n");
7287
7288 while (size-- > 0)
7289 {
7290 char elem[2];
7291
7292 elem[0] = tohex ((*data >> 4) & 0xf);
7293 elem[1] = tohex (*data++ & 0xf);
7294
7295 buffer_grow (buffer, elem, 2);
7296 }
7297
7298 buffer_grow_str (buffer, "</raw>\n");
7299}
7300
969c39fb
MM
7301/* See to_read_btrace target method. */
7302
7303static int
9accd112 7304linux_low_read_btrace (struct btrace_target_info *tinfo, struct buffer *buffer,
add67df8 7305 enum btrace_read_type type)
9accd112 7306{
734b0e4b 7307 struct btrace_data btrace;
9accd112 7308 struct btrace_block *block;
969c39fb 7309 enum btrace_error err;
9accd112
MM
7310 int i;
7311
734b0e4b
MM
7312 btrace_data_init (&btrace);
7313
969c39fb
MM
7314 err = linux_read_btrace (&btrace, tinfo, type);
7315 if (err != BTRACE_ERR_NONE)
7316 {
7317 if (err == BTRACE_ERR_OVERFLOW)
7318 buffer_grow_str0 (buffer, "E.Overflow.");
7319 else
7320 buffer_grow_str0 (buffer, "E.Generic Error.");
7321
b20a6524 7322 goto err;
969c39fb 7323 }
9accd112 7324
734b0e4b
MM
7325 switch (btrace.format)
7326 {
7327 case BTRACE_FORMAT_NONE:
7328 buffer_grow_str0 (buffer, "E.No Trace.");
b20a6524 7329 goto err;
734b0e4b
MM
7330
7331 case BTRACE_FORMAT_BTS:
7332 buffer_grow_str (buffer, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
7333 buffer_grow_str (buffer, "<btrace version=\"1.0\">\n");
9accd112 7334
734b0e4b
MM
7335 for (i = 0;
7336 VEC_iterate (btrace_block_s, btrace.variant.bts.blocks, i, block);
7337 i++)
7338 buffer_xml_printf (buffer, "<block begin=\"0x%s\" end=\"0x%s\"/>\n",
7339 paddress (block->begin), paddress (block->end));
9accd112 7340
734b0e4b
MM
7341 buffer_grow_str0 (buffer, "</btrace>\n");
7342 break;
7343
b20a6524
MM
7344 case BTRACE_FORMAT_PT:
7345 buffer_grow_str (buffer, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
7346 buffer_grow_str (buffer, "<btrace version=\"1.0\">\n");
7347 buffer_grow_str (buffer, "<pt>\n");
7348
7349 linux_low_encode_pt_config (buffer, &btrace.variant.pt.config);
9accd112 7350
b20a6524
MM
7351 linux_low_encode_raw (buffer, btrace.variant.pt.data,
7352 btrace.variant.pt.size);
7353
7354 buffer_grow_str (buffer, "</pt>\n");
7355 buffer_grow_str0 (buffer, "</btrace>\n");
7356 break;
7357
7358 default:
7359 buffer_grow_str0 (buffer, "E.Unsupported Trace Format.");
7360 goto err;
734b0e4b 7361 }
969c39fb 7362
734b0e4b 7363 btrace_data_fini (&btrace);
969c39fb 7364 return 0;
b20a6524
MM
7365
7366err:
7367 btrace_data_fini (&btrace);
7368 return -1;
9accd112 7369}
f4abbc16
MM
7370
7371/* See to_btrace_conf target method. */
7372
7373static int
7374linux_low_btrace_conf (const struct btrace_target_info *tinfo,
7375 struct buffer *buffer)
7376{
7377 const struct btrace_config *conf;
7378
7379 buffer_grow_str (buffer, "<!DOCTYPE btrace-conf SYSTEM \"btrace-conf.dtd\">\n");
7380 buffer_grow_str (buffer, "<btrace-conf version=\"1.0\">\n");
7381
7382 conf = linux_btrace_conf (tinfo);
7383 if (conf != NULL)
7384 {
7385 switch (conf->format)
7386 {
7387 case BTRACE_FORMAT_NONE:
7388 break;
7389
7390 case BTRACE_FORMAT_BTS:
d33501a5
MM
7391 buffer_xml_printf (buffer, "<bts");
7392 buffer_xml_printf (buffer, " size=\"0x%x\"", conf->bts.size);
7393 buffer_xml_printf (buffer, " />\n");
f4abbc16 7394 break;
b20a6524
MM
7395
7396 case BTRACE_FORMAT_PT:
7397 buffer_xml_printf (buffer, "<pt");
7398 buffer_xml_printf (buffer, " size=\"0x%x\"", conf->pt.size);
7399 buffer_xml_printf (buffer, "/>\n");
7400 break;
f4abbc16
MM
7401 }
7402 }
7403
7404 buffer_grow_str0 (buffer, "</btrace-conf>\n");
7405 return 0;
7406}
9accd112
MM
7407#endif /* HAVE_LINUX_BTRACE */
7408
7b669087
GB
7409/* See nat/linux-nat.h. */
7410
7411ptid_t
7412current_lwp_ptid (void)
7413{
7414 return ptid_of (current_thread);
7415}
7416
dd373349
AT
7417/* Implementation of the target_ops method "breakpoint_kind_from_pc". */
7418
7419static int
7420linux_breakpoint_kind_from_pc (CORE_ADDR *pcptr)
7421{
7422 if (the_low_target.breakpoint_kind_from_pc != NULL)
7423 return (*the_low_target.breakpoint_kind_from_pc) (pcptr);
7424 else
1652a986 7425 return default_breakpoint_kind_from_pc (pcptr);
dd373349
AT
7426}
7427
7428/* Implementation of the target_ops method "sw_breakpoint_from_kind". */
7429
7430static const gdb_byte *
7431linux_sw_breakpoint_from_kind (int kind, int *size)
7432{
7433 gdb_assert (the_low_target.sw_breakpoint_from_kind != NULL);
7434
7435 return (*the_low_target.sw_breakpoint_from_kind) (kind, size);
7436}
7437
769ef81f
AT
7438/* Implementation of the target_ops method
7439 "breakpoint_kind_from_current_state". */
7440
7441static int
7442linux_breakpoint_kind_from_current_state (CORE_ADDR *pcptr)
7443{
7444 if (the_low_target.breakpoint_kind_from_current_state != NULL)
7445 return (*the_low_target.breakpoint_kind_from_current_state) (pcptr);
7446 else
7447 return linux_breakpoint_kind_from_pc (pcptr);
7448}
7449
276d4552
YQ
7450/* Default implementation of linux_target_ops method "set_pc" for
7451 32-bit pc register which is literally named "pc". */
7452
7453void
7454linux_set_pc_32bit (struct regcache *regcache, CORE_ADDR pc)
7455{
7456 uint32_t newpc = pc;
7457
7458 supply_register_by_name (regcache, "pc", &newpc);
7459}
7460
7461/* Default implementation of linux_target_ops method "get_pc" for
7462 32-bit pc register which is literally named "pc". */
7463
7464CORE_ADDR
7465linux_get_pc_32bit (struct regcache *regcache)
7466{
7467 uint32_t pc;
7468
7469 collect_register_by_name (regcache, "pc", &pc);
7470 if (debug_threads)
7471 debug_printf ("stop pc is 0x%" PRIx32 "\n", pc);
7472 return pc;
7473}
7474
6f69e520
YQ
7475/* Default implementation of linux_target_ops method "set_pc" for
7476 64-bit pc register which is literally named "pc". */
7477
7478void
7479linux_set_pc_64bit (struct regcache *regcache, CORE_ADDR pc)
7480{
7481 uint64_t newpc = pc;
7482
7483 supply_register_by_name (regcache, "pc", &newpc);
7484}
7485
7486/* Default implementation of linux_target_ops method "get_pc" for
7487 64-bit pc register which is literally named "pc". */
7488
7489CORE_ADDR
7490linux_get_pc_64bit (struct regcache *regcache)
7491{
7492 uint64_t pc;
7493
7494 collect_register_by_name (regcache, "pc", &pc);
7495 if (debug_threads)
7496 debug_printf ("stop pc is 0x%" PRIx64 "\n", pc);
7497 return pc;
7498}
7499
7500
ce3a066d
DJ
7501static struct target_ops linux_target_ops = {
7502 linux_create_inferior,
ece66d65 7503 linux_post_create_inferior,
ce3a066d
DJ
7504 linux_attach,
7505 linux_kill,
6ad8ae5c 7506 linux_detach,
8336d594 7507 linux_mourn,
444d6139 7508 linux_join,
ce3a066d
DJ
7509 linux_thread_alive,
7510 linux_resume,
7511 linux_wait,
7512 linux_fetch_registers,
7513 linux_store_registers,
90d74c30 7514 linux_prepare_to_access_memory,
0146f85b 7515 linux_done_accessing_memory,
ce3a066d
DJ
7516 linux_read_memory,
7517 linux_write_memory,
2f2893d9 7518 linux_look_up_symbols,
ef57601b 7519 linux_request_interrupt,
aa691b87 7520 linux_read_auxv,
802e8e6d 7521 linux_supports_z_point_type,
d993e290
PA
7522 linux_insert_point,
7523 linux_remove_point,
3e572f71
PA
7524 linux_stopped_by_sw_breakpoint,
7525 linux_supports_stopped_by_sw_breakpoint,
7526 linux_stopped_by_hw_breakpoint,
7527 linux_supports_stopped_by_hw_breakpoint,
70b90b91 7528 linux_supports_hardware_single_step,
e013ee27
OF
7529 linux_stopped_by_watchpoint,
7530 linux_stopped_data_address,
db0dfaa0
LM
7531#if defined(__UCLIBC__) && defined(HAS_NOMMU) \
7532 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
7533 && defined(PT_TEXT_END_ADDR)
52fb6437 7534 linux_read_offsets,
dae5f5cf
DJ
7535#else
7536 NULL,
7537#endif
7538#ifdef USE_THREAD_DB
7539 thread_db_get_tls_address,
7540#else
7541 NULL,
52fb6437 7542#endif
efcbbd14 7543 linux_qxfer_spu,
59a016f0 7544 hostio_last_error_from_errno,
07e059b5 7545 linux_qxfer_osdata,
4aa995e1 7546 linux_xfer_siginfo,
bd99dc85
PA
7547 linux_supports_non_stop,
7548 linux_async,
7549 linux_start_non_stop,
cdbfd419 7550 linux_supports_multi_process,
89245bc0
DB
7551 linux_supports_fork_events,
7552 linux_supports_vfork_events,
94585166 7553 linux_supports_exec_events,
de0d863e 7554 linux_handle_new_gdb_connection,
cdbfd419 7555#ifdef USE_THREAD_DB
dc146f7c 7556 thread_db_handle_monitor_command,
cdbfd419 7557#else
dc146f7c 7558 NULL,
cdbfd419 7559#endif
d26e3629 7560 linux_common_core_of_thread,
78d85199 7561 linux_read_loadmap,
219f2f23
PA
7562 linux_process_qsupported,
7563 linux_supports_tracepoints,
7564 linux_read_pc,
8336d594
PA
7565 linux_write_pc,
7566 linux_thread_stopped,
7984d532 7567 NULL,
711e434b 7568 linux_pause_all,
7984d532 7569 linux_unpause_all,
fa593d66 7570 linux_stabilize_threads,
6a271cae 7571 linux_install_fast_tracepoint_jump_pad,
03583c20
UW
7572 linux_emit_ops,
7573 linux_supports_disable_randomization,
405f8e94 7574 linux_get_min_fast_tracepoint_insn_len,
2268b414 7575 linux_qxfer_libraries_svr4,
d1feda86 7576 linux_supports_agent,
9accd112
MM
7577#ifdef HAVE_LINUX_BTRACE
7578 linux_supports_btrace,
0568462b 7579 linux_enable_btrace,
969c39fb 7580 linux_low_disable_btrace,
9accd112 7581 linux_low_read_btrace,
f4abbc16 7582 linux_low_btrace_conf,
9accd112
MM
7583#else
7584 NULL,
7585 NULL,
7586 NULL,
7587 NULL,
f4abbc16 7588 NULL,
9accd112 7589#endif
c2d6af84 7590 linux_supports_range_stepping,
e57f1de3 7591 linux_proc_pid_to_exec_file,
14d2069a
GB
7592 linux_mntns_open_cloexec,
7593 linux_mntns_unlink,
7594 linux_mntns_readlink,
dd373349 7595 linux_breakpoint_kind_from_pc,
79efa585
SM
7596 linux_sw_breakpoint_from_kind,
7597 linux_proc_tid_get_name,
7d00775e 7598 linux_breakpoint_kind_from_current_state,
82075af2
JS
7599 linux_supports_software_single_step,
7600 linux_supports_catch_syscall,
ae91f625 7601 linux_get_ipa_tdesc_idx,
ce3a066d
DJ
7602};
7603
3aee8918
PA
7604#ifdef HAVE_LINUX_REGSETS
7605void
7606initialize_regsets_info (struct regsets_info *info)
7607{
7608 for (info->num_regsets = 0;
7609 info->regsets[info->num_regsets].size >= 0;
7610 info->num_regsets++)
7611 ;
3aee8918
PA
7612}
7613#endif
7614
da6d8c04
DJ
7615void
7616initialize_low (void)
7617{
bd99dc85 7618 struct sigaction sigchld_action;
dd373349 7619
bd99dc85 7620 memset (&sigchld_action, 0, sizeof (sigchld_action));
ce3a066d 7621 set_target_ops (&linux_target_ops);
dd373349 7622
aa7c7447 7623 linux_ptrace_init_warnings ();
bd99dc85
PA
7624
7625 sigchld_action.sa_handler = sigchld_handler;
7626 sigemptyset (&sigchld_action.sa_mask);
7627 sigchld_action.sa_flags = SA_RESTART;
7628 sigaction (SIGCHLD, &sigchld_action, NULL);
3aee8918
PA
7629
7630 initialize_low_arch ();
89245bc0
DB
7631
7632 linux_check_ptrace_features ();
da6d8c04 7633}