]> git.ipfire.org Git - thirdparty/binutils-gdb.git/blame - gdb/gdbserver/linux-low.c
* inferiors.c (add_thread): Fix whitespace.
[thirdparty/binutils-gdb.git] / gdb / gdbserver / linux-low.c
CommitLineData
da6d8c04 1/* Low level interface to ptrace, for the remote server for GDB.
ecd75fc8 2 Copyright (C) 1995-2014 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"
d26e3629 21#include "linux-osdata.h"
58b4daa5 22#include "agent.h"
da6d8c04 23
96d7229d
LM
24#include "nat/linux-nat.h"
25#include "nat/linux-waitpid.h"
8bdce1ff 26#include "gdb_wait.h"
da6d8c04 27#include <stdio.h>
da6d8c04 28#include <sys/ptrace.h>
af96c192 29#include "linux-ptrace.h"
e3deef73 30#include "linux-procfs.h"
da6d8c04
DJ
31#include <signal.h>
32#include <sys/ioctl.h>
33#include <fcntl.h>
d07c63e7 34#include <string.h>
0a30fbc4
DJ
35#include <stdlib.h>
36#include <unistd.h>
fa6a77dc 37#include <errno.h>
fd500816 38#include <sys/syscall.h>
f9387fc3 39#include <sched.h>
07e059b5
VP
40#include <ctype.h>
41#include <pwd.h>
42#include <sys/types.h>
43#include <dirent.h>
53ce3c39 44#include <sys/stat.h>
efcbbd14 45#include <sys/vfs.h>
1570b33e 46#include <sys/uio.h>
602e3198 47#include "filestuff.h"
c144c7a0 48#include "tracepoint.h"
533b0600 49#include "hostio.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
efcbbd14
UW
57
58#ifndef SPUFS_MAGIC
59#define SPUFS_MAGIC 0x23c9b64e
60#endif
da6d8c04 61
03583c20
UW
62#ifdef HAVE_PERSONALITY
63# include <sys/personality.h>
64# if !HAVE_DECL_ADDR_NO_RANDOMIZE
65# define ADDR_NO_RANDOMIZE 0x0040000
66# endif
67#endif
68
fd462a61
DJ
69#ifndef O_LARGEFILE
70#define O_LARGEFILE 0
71#endif
72
ec8ebe72
DE
73#ifndef W_STOPCODE
74#define W_STOPCODE(sig) ((sig) << 8 | 0x7f)
75#endif
76
1a981360
PA
77/* This is the kernel's hard limit. Not to be confused with
78 SIGRTMIN. */
79#ifndef __SIGRTMIN
80#define __SIGRTMIN 32
81#endif
82
db0dfaa0
LM
83/* Some targets did not define these ptrace constants from the start,
84 so gdbserver defines them locally here. In the future, these may
85 be removed after they are added to asm/ptrace.h. */
86#if !(defined(PT_TEXT_ADDR) \
87 || defined(PT_DATA_ADDR) \
88 || defined(PT_TEXT_END_ADDR))
89#if defined(__mcoldfire__)
90/* These are still undefined in 3.10 kernels. */
91#define PT_TEXT_ADDR 49*4
92#define PT_DATA_ADDR 50*4
93#define PT_TEXT_END_ADDR 51*4
94/* BFIN already defines these since at least 2.6.32 kernels. */
95#elif defined(BFIN)
96#define PT_TEXT_ADDR 220
97#define PT_TEXT_END_ADDR 224
98#define PT_DATA_ADDR 228
99/* These are still undefined in 3.10 kernels. */
100#elif defined(__TMS320C6X__)
101#define PT_TEXT_ADDR (0x10000*4)
102#define PT_DATA_ADDR (0x10004*4)
103#define PT_TEXT_END_ADDR (0x10008*4)
104#endif
105#endif
106
9accd112
MM
107#ifdef HAVE_LINUX_BTRACE
108# include "linux-btrace.h"
109#endif
110
8365dcf5
TJB
111#ifndef HAVE_ELF32_AUXV_T
112/* Copied from glibc's elf.h. */
113typedef struct
114{
115 uint32_t a_type; /* Entry type */
116 union
117 {
118 uint32_t a_val; /* Integer value */
119 /* We use to have pointer elements added here. We cannot do that,
120 though, since it does not work when using 32-bit definitions
121 on 64-bit platforms and vice versa. */
122 } a_un;
123} Elf32_auxv_t;
124#endif
125
126#ifndef HAVE_ELF64_AUXV_T
127/* Copied from glibc's elf.h. */
128typedef struct
129{
130 uint64_t a_type; /* Entry type */
131 union
132 {
133 uint64_t a_val; /* Integer value */
134 /* We use to have pointer elements added here. We cannot do that,
135 though, since it does not work when using 32-bit definitions
136 on 64-bit platforms and vice versa. */
137 } a_un;
138} Elf64_auxv_t;
139#endif
140
24a09b5f
DJ
141/* ``all_threads'' is keyed by the LWP ID, which we use as the GDB protocol
142 representation of the thread ID.
611cb4a5 143
54a0b537 144 ``all_lwps'' is keyed by the process ID - which on Linux is (presently)
95954743
PA
145 the same as the LWP ID.
146
147 ``all_processes'' is keyed by the "overall process ID", which
148 GNU/Linux calls tgid, "thread group ID". */
0d62e5e8 149
54a0b537 150struct inferior_list all_lwps;
0d62e5e8 151
05044653
PA
152/* A list of all unknown processes which receive stop signals. Some
153 other process will presumably claim each of these as forked
154 children momentarily. */
24a09b5f 155
05044653
PA
156struct simple_pid_list
157{
158 /* The process ID. */
159 int pid;
160
161 /* The status as reported by waitpid. */
162 int status;
163
164 /* Next in chain. */
165 struct simple_pid_list *next;
166};
167struct simple_pid_list *stopped_pids;
168
169/* Trivial list manipulation functions to keep track of a list of new
170 stopped processes. */
171
172static void
173add_to_pid_list (struct simple_pid_list **listp, int pid, int status)
174{
175 struct simple_pid_list *new_pid = xmalloc (sizeof (struct simple_pid_list));
176
177 new_pid->pid = pid;
178 new_pid->status = status;
179 new_pid->next = *listp;
180 *listp = new_pid;
181}
182
183static int
184pull_pid_from_list (struct simple_pid_list **listp, int pid, int *statusp)
185{
186 struct simple_pid_list **p;
187
188 for (p = listp; *p != NULL; p = &(*p)->next)
189 if ((*p)->pid == pid)
190 {
191 struct simple_pid_list *next = (*p)->next;
192
193 *statusp = (*p)->status;
194 xfree (*p);
195 *p = next;
196 return 1;
197 }
198 return 0;
199}
24a09b5f 200
bde24c0a
PA
201enum stopping_threads_kind
202 {
203 /* Not stopping threads presently. */
204 NOT_STOPPING_THREADS,
205
206 /* Stopping threads. */
207 STOPPING_THREADS,
208
209 /* Stopping and suspending threads. */
210 STOPPING_AND_SUSPENDING_THREADS
211 };
212
213/* This is set while stop_all_lwps is in effect. */
214enum stopping_threads_kind stopping_threads = NOT_STOPPING_THREADS;
0d62e5e8
DJ
215
216/* FIXME make into a target method? */
24a09b5f 217int using_threads = 1;
24a09b5f 218
fa593d66
PA
219/* True if we're presently stabilizing threads (moving them out of
220 jump pads). */
221static int stabilizing_threads;
222
2acc282a 223static void linux_resume_one_lwp (struct lwp_info *lwp,
54a0b537 224 int step, int signal, siginfo_t *info);
2bd7c093 225static void linux_resume (struct thread_resume *resume_info, size_t n);
7984d532
PA
226static void stop_all_lwps (int suspend, struct lwp_info *except);
227static void unstop_all_lwps (int unsuspend, struct lwp_info *except);
95954743 228static int linux_wait_for_event (ptid_t ptid, int *wstat, int options);
95954743 229static void *add_lwp (ptid_t ptid);
c35fafde 230static int linux_stopped_by_watchpoint (void);
95954743 231static void mark_lwp_dead (struct lwp_info *lwp, int wstat);
d50171e4 232static void proceed_all_lwps (void);
d50171e4
PA
233static int finish_step_over (struct lwp_info *lwp);
234static CORE_ADDR get_stop_pc (struct lwp_info *lwp);
235static int kill_lwp (unsigned long lwpid, int signo);
236
237/* True if the low target can hardware single-step. Such targets
238 don't need a BREAKPOINT_REINSERT_ADDR callback. */
239
240static int
241can_hardware_single_step (void)
242{
243 return (the_low_target.breakpoint_reinsert_addr == NULL);
244}
245
246/* True if the low target supports memory breakpoints. If so, we'll
247 have a GET_PC implementation. */
248
249static int
250supports_breakpoints (void)
251{
252 return (the_low_target.get_pc != NULL);
253}
0d62e5e8 254
fa593d66
PA
255/* Returns true if this target can support fast tracepoints. This
256 does not mean that the in-process agent has been loaded in the
257 inferior. */
258
259static int
260supports_fast_tracepoints (void)
261{
262 return the_low_target.install_fast_tracepoint_jump_pad != NULL;
263}
264
c2d6af84
PA
265/* True if LWP is stopped in its stepping range. */
266
267static int
268lwp_in_step_range (struct lwp_info *lwp)
269{
270 CORE_ADDR pc = lwp->stop_pc;
271
272 return (pc >= lwp->step_range_start && pc < lwp->step_range_end);
273}
274
0d62e5e8
DJ
275struct pending_signals
276{
277 int signal;
32ca6d61 278 siginfo_t info;
0d62e5e8
DJ
279 struct pending_signals *prev;
280};
611cb4a5 281
bd99dc85
PA
282/* The read/write ends of the pipe registered as waitable file in the
283 event loop. */
284static int linux_event_pipe[2] = { -1, -1 };
285
286/* True if we're currently in async mode. */
287#define target_is_async_p() (linux_event_pipe[0] != -1)
288
02fc4de7 289static void send_sigstop (struct lwp_info *lwp);
bd99dc85
PA
290static void wait_for_sigstop (struct inferior_list_entry *entry);
291
d0722149
DE
292/* Return non-zero if HEADER is a 64-bit ELF file. */
293
294static int
214d508e 295elf_64_header_p (const Elf64_Ehdr *header, unsigned int *machine)
d0722149 296{
214d508e
L
297 if (header->e_ident[EI_MAG0] == ELFMAG0
298 && header->e_ident[EI_MAG1] == ELFMAG1
299 && header->e_ident[EI_MAG2] == ELFMAG2
300 && header->e_ident[EI_MAG3] == ELFMAG3)
301 {
302 *machine = header->e_machine;
303 return header->e_ident[EI_CLASS] == ELFCLASS64;
304
305 }
306 *machine = EM_NONE;
307 return -1;
d0722149
DE
308}
309
310/* Return non-zero if FILE is a 64-bit ELF file,
311 zero if the file is not a 64-bit ELF file,
312 and -1 if the file is not accessible or doesn't exist. */
313
be07f1a2 314static int
214d508e 315elf_64_file_p (const char *file, unsigned int *machine)
d0722149 316{
957f3f49 317 Elf64_Ehdr header;
d0722149
DE
318 int fd;
319
320 fd = open (file, O_RDONLY);
321 if (fd < 0)
322 return -1;
323
324 if (read (fd, &header, sizeof (header)) != sizeof (header))
325 {
326 close (fd);
327 return 0;
328 }
329 close (fd);
330
214d508e 331 return elf_64_header_p (&header, machine);
d0722149
DE
332}
333
be07f1a2
PA
334/* Accepts an integer PID; Returns true if the executable PID is
335 running is a 64-bit ELF file.. */
336
337int
214d508e 338linux_pid_exe_is_elf_64_file (int pid, unsigned int *machine)
be07f1a2 339{
d8d2a3ee 340 char file[PATH_MAX];
be07f1a2
PA
341
342 sprintf (file, "/proc/%d/exe", pid);
214d508e 343 return elf_64_file_p (file, machine);
be07f1a2
PA
344}
345
bd99dc85
PA
346static void
347delete_lwp (struct lwp_info *lwp)
348{
349 remove_thread (get_lwp_thread (lwp));
80894984 350 remove_inferior (&all_lwps, &lwp->entry);
aa5ca48f 351 free (lwp->arch_private);
bd99dc85
PA
352 free (lwp);
353}
354
95954743
PA
355/* Add a process to the common process list, and set its private
356 data. */
357
358static struct process_info *
359linux_add_process (int pid, int attached)
360{
361 struct process_info *proc;
362
95954743
PA
363 proc = add_process (pid, attached);
364 proc->private = xcalloc (1, sizeof (*proc->private));
365
3aee8918
PA
366 /* Set the arch when the first LWP stops. */
367 proc->private->new_inferior = 1;
368
aa5ca48f
DE
369 if (the_low_target.new_process != NULL)
370 proc->private->arch_private = the_low_target.new_process ();
371
95954743
PA
372 return proc;
373}
374
bd99dc85
PA
375/* Handle a GNU/Linux extended wait response. If we see a clone
376 event, we need to add the new LWP to our list (and not report the
377 trap to higher layers). */
0d62e5e8 378
24a09b5f 379static void
54a0b537 380handle_extended_wait (struct lwp_info *event_child, int wstat)
24a09b5f
DJ
381{
382 int event = wstat >> 16;
54a0b537 383 struct lwp_info *new_lwp;
24a09b5f
DJ
384
385 if (event == PTRACE_EVENT_CLONE)
386 {
95954743 387 ptid_t ptid;
24a09b5f 388 unsigned long new_pid;
05044653 389 int ret, status;
24a09b5f 390
b8e1b30e 391 ptrace (PTRACE_GETEVENTMSG, lwpid_of (event_child), (PTRACE_TYPE_ARG3) 0,
56f7af9c 392 &new_pid);
24a09b5f
DJ
393
394 /* If we haven't already seen the new PID stop, wait for it now. */
05044653 395 if (!pull_pid_from_list (&stopped_pids, new_pid, &status))
24a09b5f
DJ
396 {
397 /* The new child has a pending SIGSTOP. We can't affect it until it
398 hits the SIGSTOP, but we're already attached. */
399
97438e3f 400 ret = my_waitpid (new_pid, &status, __WALL);
24a09b5f
DJ
401
402 if (ret == -1)
403 perror_with_name ("waiting for new child");
404 else if (ret != new_pid)
405 warning ("wait returned unexpected PID %d", ret);
da5898ce 406 else if (!WIFSTOPPED (status))
24a09b5f
DJ
407 warning ("wait returned unexpected status 0x%x", status);
408 }
409
95954743
PA
410 ptid = ptid_build (pid_of (event_child), new_pid, 0);
411 new_lwp = (struct lwp_info *) add_lwp (ptid);
412 add_thread (ptid, new_lwp);
24a09b5f 413
e27d73f6
DE
414 /* Either we're going to immediately resume the new thread
415 or leave it stopped. linux_resume_one_lwp is a nop if it
416 thinks the thread is currently running, so set this first
417 before calling linux_resume_one_lwp. */
418 new_lwp->stopped = 1;
419
bde24c0a
PA
420 /* If we're suspending all threads, leave this one suspended
421 too. */
422 if (stopping_threads == STOPPING_AND_SUSPENDING_THREADS)
423 new_lwp->suspended = 1;
424
da5898ce
DJ
425 /* Normally we will get the pending SIGSTOP. But in some cases
426 we might get another signal delivered to the group first.
f21cc1a2 427 If we do get another signal, be sure not to lose it. */
da5898ce
DJ
428 if (WSTOPSIG (status) == SIGSTOP)
429 {
bde24c0a 430 if (stopping_threads != NOT_STOPPING_THREADS)
d50171e4
PA
431 new_lwp->stop_pc = get_stop_pc (new_lwp);
432 else
e27d73f6 433 linux_resume_one_lwp (new_lwp, 0, 0, NULL);
da5898ce 434 }
24a09b5f 435 else
da5898ce 436 {
54a0b537 437 new_lwp->stop_expected = 1;
d50171e4 438
bde24c0a 439 if (stopping_threads != NOT_STOPPING_THREADS)
da5898ce 440 {
d50171e4 441 new_lwp->stop_pc = get_stop_pc (new_lwp);
54a0b537
PA
442 new_lwp->status_pending_p = 1;
443 new_lwp->status_pending = status;
da5898ce
DJ
444 }
445 else
446 /* Pass the signal on. This is what GDB does - except
447 shouldn't we really report it instead? */
e27d73f6 448 linux_resume_one_lwp (new_lwp, 0, WSTOPSIG (status), NULL);
da5898ce 449 }
24a09b5f
DJ
450
451 /* Always resume the current thread. If we are stopping
452 threads, it will have a pending SIGSTOP; we may as well
453 collect it now. */
2acc282a 454 linux_resume_one_lwp (event_child, event_child->stepping, 0, NULL);
24a09b5f
DJ
455 }
456}
457
d50171e4
PA
458/* Return the PC as read from the regcache of LWP, without any
459 adjustment. */
460
461static CORE_ADDR
462get_pc (struct lwp_info *lwp)
463{
464 struct thread_info *saved_inferior;
465 struct regcache *regcache;
466 CORE_ADDR pc;
467
468 if (the_low_target.get_pc == NULL)
469 return 0;
470
471 saved_inferior = current_inferior;
472 current_inferior = get_lwp_thread (lwp);
473
474 regcache = get_thread_regcache (current_inferior, 1);
475 pc = (*the_low_target.get_pc) (regcache);
476
477 if (debug_threads)
87ce2a04 478 debug_printf ("pc is 0x%lx\n", (long) pc);
d50171e4
PA
479
480 current_inferior = saved_inferior;
481 return pc;
482}
483
484/* This function should only be called if LWP got a SIGTRAP.
0d62e5e8
DJ
485 The SIGTRAP could mean several things.
486
487 On i386, where decr_pc_after_break is non-zero:
488 If we were single-stepping this process using PTRACE_SINGLESTEP,
489 we will get only the one SIGTRAP (even if the instruction we
490 stepped over was a breakpoint). The value of $eip will be the
491 next instruction.
492 If we continue the process using PTRACE_CONT, we will get a
493 SIGTRAP when we hit a breakpoint. The value of $eip will be
494 the instruction after the breakpoint (i.e. needs to be
495 decremented). If we report the SIGTRAP to GDB, we must also
496 report the undecremented PC. If we cancel the SIGTRAP, we
497 must resume at the decremented PC.
498
499 (Presumably, not yet tested) On a non-decr_pc_after_break machine
500 with hardware or kernel single-step:
501 If we single-step over a breakpoint instruction, our PC will
502 point at the following instruction. If we continue and hit a
503 breakpoint instruction, our PC will point at the breakpoint
504 instruction. */
505
506static CORE_ADDR
d50171e4 507get_stop_pc (struct lwp_info *lwp)
0d62e5e8 508{
d50171e4
PA
509 CORE_ADDR stop_pc;
510
511 if (the_low_target.get_pc == NULL)
512 return 0;
0d62e5e8 513
d50171e4
PA
514 stop_pc = get_pc (lwp);
515
bdabb078
PA
516 if (WSTOPSIG (lwp->last_status) == SIGTRAP
517 && !lwp->stepping
518 && !lwp->stopped_by_watchpoint
519 && lwp->last_status >> 16 == 0)
47c0c975
DE
520 stop_pc -= the_low_target.decr_pc_after_break;
521
522 if (debug_threads)
87ce2a04 523 debug_printf ("stop pc is 0x%lx\n", (long) stop_pc);
47c0c975
DE
524
525 return stop_pc;
0d62e5e8 526}
ce3a066d 527
0d62e5e8 528static void *
95954743 529add_lwp (ptid_t ptid)
611cb4a5 530{
54a0b537 531 struct lwp_info *lwp;
0d62e5e8 532
54a0b537
PA
533 lwp = (struct lwp_info *) xmalloc (sizeof (*lwp));
534 memset (lwp, 0, sizeof (*lwp));
0d62e5e8 535
80894984 536 lwp->entry.id = ptid;
0d62e5e8 537
aa5ca48f
DE
538 if (the_low_target.new_thread != NULL)
539 lwp->arch_private = the_low_target.new_thread ();
540
80894984 541 add_inferior_to_list (&all_lwps, &lwp->entry);
0d62e5e8 542
54a0b537 543 return lwp;
0d62e5e8 544}
611cb4a5 545
da6d8c04
DJ
546/* Start an inferior process and returns its pid.
547 ALLARGS is a vector of program-name and args. */
548
ce3a066d
DJ
549static int
550linux_create_inferior (char *program, char **allargs)
da6d8c04 551{
03583c20
UW
552#ifdef HAVE_PERSONALITY
553 int personality_orig = 0, personality_set = 0;
554#endif
a6dbe5df 555 struct lwp_info *new_lwp;
da6d8c04 556 int pid;
95954743 557 ptid_t ptid;
da6d8c04 558
03583c20
UW
559#ifdef HAVE_PERSONALITY
560 if (disable_randomization)
561 {
562 errno = 0;
563 personality_orig = personality (0xffffffff);
564 if (errno == 0 && !(personality_orig & ADDR_NO_RANDOMIZE))
565 {
566 personality_set = 1;
567 personality (personality_orig | ADDR_NO_RANDOMIZE);
568 }
569 if (errno != 0 || (personality_set
570 && !(personality (0xffffffff) & ADDR_NO_RANDOMIZE)))
571 warning ("Error disabling address space randomization: %s",
572 strerror (errno));
573 }
574#endif
575
42c81e2a 576#if defined(__UCLIBC__) && defined(HAS_NOMMU)
52fb6437
NS
577 pid = vfork ();
578#else
da6d8c04 579 pid = fork ();
52fb6437 580#endif
da6d8c04
DJ
581 if (pid < 0)
582 perror_with_name ("fork");
583
584 if (pid == 0)
585 {
602e3198 586 close_most_fds ();
b8e1b30e 587 ptrace (PTRACE_TRACEME, 0, (PTRACE_TYPE_ARG3) 0, (PTRACE_TYPE_ARG4) 0);
da6d8c04 588
1a981360 589#ifndef __ANDROID__ /* Bionic doesn't use SIGRTMIN the way glibc does. */
254787d4 590 signal (__SIGRTMIN + 1, SIG_DFL);
60c3d7b0 591#endif
0d62e5e8 592
a9fa9f7d
DJ
593 setpgid (0, 0);
594
e0f9f062
DE
595 /* If gdbserver is connected to gdb via stdio, redirect the inferior's
596 stdout to stderr so that inferior i/o doesn't corrupt the connection.
597 Also, redirect stdin to /dev/null. */
598 if (remote_connection_is_stdio ())
599 {
600 close (0);
601 open ("/dev/null", O_RDONLY);
602 dup2 (2, 1);
3e52c33d
JK
603 if (write (2, "stdin/stdout redirected\n",
604 sizeof ("stdin/stdout redirected\n") - 1) < 0)
8c29b58e
YQ
605 {
606 /* Errors ignored. */;
607 }
e0f9f062
DE
608 }
609
2b876972
DJ
610 execv (program, allargs);
611 if (errno == ENOENT)
612 execvp (program, allargs);
da6d8c04
DJ
613
614 fprintf (stderr, "Cannot exec %s: %s.\n", program,
d07c63e7 615 strerror (errno));
da6d8c04
DJ
616 fflush (stderr);
617 _exit (0177);
618 }
619
03583c20
UW
620#ifdef HAVE_PERSONALITY
621 if (personality_set)
622 {
623 errno = 0;
624 personality (personality_orig);
625 if (errno != 0)
626 warning ("Error restoring address space randomization: %s",
627 strerror (errno));
628 }
629#endif
630
95954743
PA
631 linux_add_process (pid, 0);
632
633 ptid = ptid_build (pid, pid, 0);
634 new_lwp = add_lwp (ptid);
635 add_thread (ptid, new_lwp);
a6dbe5df 636 new_lwp->must_set_ptrace_flags = 1;
611cb4a5 637
a9fa9f7d 638 return pid;
da6d8c04
DJ
639}
640
641/* Attach to an inferior process. */
642
95954743
PA
643static void
644linux_attach_lwp_1 (unsigned long lwpid, int initial)
da6d8c04 645{
95954743 646 ptid_t ptid;
54a0b537 647 struct lwp_info *new_lwp;
611cb4a5 648
b8e1b30e 649 if (ptrace (PTRACE_ATTACH, lwpid, (PTRACE_TYPE_ARG3) 0, (PTRACE_TYPE_ARG4) 0)
56f7af9c 650 != 0)
da6d8c04 651 {
87b0bb13
JK
652 struct buffer buffer;
653
95954743 654 if (!initial)
2d717e4f
DJ
655 {
656 /* If we fail to attach to an LWP, just warn. */
95954743 657 fprintf (stderr, "Cannot attach to lwp %ld: %s (%d)\n", lwpid,
2d717e4f
DJ
658 strerror (errno), errno);
659 fflush (stderr);
660 return;
661 }
5f572dec
JK
662
663 /* If we fail to attach to a process, report an error. */
87b0bb13
JK
664 buffer_init (&buffer);
665 linux_ptrace_attach_warnings (lwpid, &buffer);
666 buffer_grow_str0 (&buffer, "");
667 error ("%sCannot attach to lwp %ld: %s (%d)", buffer_finish (&buffer),
668 lwpid, strerror (errno), errno);
da6d8c04
DJ
669 }
670
95954743 671 if (initial)
e3deef73
LM
672 /* If lwp is the tgid, we handle adding existing threads later.
673 Otherwise we just add lwp without bothering about any other
674 threads. */
95954743
PA
675 ptid = ptid_build (lwpid, lwpid, 0);
676 else
677 {
678 /* Note that extracting the pid from the current inferior is
679 safe, since we're always called in the context of the same
680 process as this new thread. */
681 int pid = pid_of (get_thread_lwp (current_inferior));
682 ptid = ptid_build (pid, lwpid, 0);
683 }
24a09b5f 684
95954743
PA
685 new_lwp = (struct lwp_info *) add_lwp (ptid);
686 add_thread (ptid, new_lwp);
0d62e5e8 687
a6dbe5df
PA
688 /* We need to wait for SIGSTOP before being able to make the next
689 ptrace call on this LWP. */
690 new_lwp->must_set_ptrace_flags = 1;
691
644cebc9 692 if (linux_proc_pid_is_stopped (lwpid))
c14d7ab2
PA
693 {
694 if (debug_threads)
87ce2a04 695 debug_printf ("Attached to a stopped process\n");
c14d7ab2
PA
696
697 /* The process is definitely stopped. It is in a job control
698 stop, unless the kernel predates the TASK_STOPPED /
699 TASK_TRACED distinction, in which case it might be in a
700 ptrace stop. Make sure it is in a ptrace stop; from there we
701 can kill it, signal it, et cetera.
702
703 First make sure there is a pending SIGSTOP. Since we are
704 already attached, the process can not transition from stopped
705 to running without a PTRACE_CONT; so we know this signal will
706 go into the queue. The SIGSTOP generated by PTRACE_ATTACH is
707 probably already in the queue (unless this kernel is old
708 enough to use TASK_STOPPED for ptrace stops); but since
709 SIGSTOP is not an RT signal, it can only be queued once. */
710 kill_lwp (lwpid, SIGSTOP);
711
712 /* Finally, resume the stopped process. This will deliver the
713 SIGSTOP (or a higher priority signal, just like normal
714 PTRACE_ATTACH), which we'll catch later on. */
b8e1b30e 715 ptrace (PTRACE_CONT, lwpid, (PTRACE_TYPE_ARG3) 0, (PTRACE_TYPE_ARG4) 0);
c14d7ab2
PA
716 }
717
0d62e5e8 718 /* The next time we wait for this LWP we'll see a SIGSTOP as PTRACE_ATTACH
0e21c1ec
DE
719 brings it to a halt.
720
721 There are several cases to consider here:
722
723 1) gdbserver has already attached to the process and is being notified
1b3f6016 724 of a new thread that is being created.
d50171e4
PA
725 In this case we should ignore that SIGSTOP and resume the
726 process. This is handled below by setting stop_expected = 1,
8336d594 727 and the fact that add_thread sets last_resume_kind ==
d50171e4 728 resume_continue.
0e21c1ec
DE
729
730 2) This is the first thread (the process thread), and we're attaching
1b3f6016
PA
731 to it via attach_inferior.
732 In this case we want the process thread to stop.
d50171e4
PA
733 This is handled by having linux_attach set last_resume_kind ==
734 resume_stop after we return.
e3deef73
LM
735
736 If the pid we are attaching to is also the tgid, we attach to and
737 stop all the existing threads. Otherwise, we attach to pid and
738 ignore any other threads in the same group as this pid.
0e21c1ec
DE
739
740 3) GDB is connecting to gdbserver and is requesting an enumeration of all
1b3f6016
PA
741 existing threads.
742 In this case we want the thread to stop.
743 FIXME: This case is currently not properly handled.
744 We should wait for the SIGSTOP but don't. Things work apparently
745 because enough time passes between when we ptrace (ATTACH) and when
746 gdb makes the next ptrace call on the thread.
0d62e5e8
DJ
747
748 On the other hand, if we are currently trying to stop all threads, we
749 should treat the new thread as if we had sent it a SIGSTOP. This works
54a0b537 750 because we are guaranteed that the add_lwp call above added us to the
0e21c1ec
DE
751 end of the list, and so the new thread has not yet reached
752 wait_for_sigstop (but will). */
d50171e4 753 new_lwp->stop_expected = 1;
0d62e5e8
DJ
754}
755
95954743
PA
756void
757linux_attach_lwp (unsigned long lwpid)
758{
759 linux_attach_lwp_1 (lwpid, 0);
760}
761
e3deef73
LM
762/* Attach to PID. If PID is the tgid, attach to it and all
763 of its threads. */
764
c52daf70 765static int
a1928bad 766linux_attach (unsigned long pid)
0d62e5e8 767{
e3deef73
LM
768 /* Attach to PID. We will check for other threads
769 soon. */
95954743 770 linux_attach_lwp_1 (pid, 1);
95954743 771 linux_add_process (pid, 1);
0d62e5e8 772
bd99dc85
PA
773 if (!non_stop)
774 {
8336d594
PA
775 struct thread_info *thread;
776
777 /* Don't ignore the initial SIGSTOP if we just attached to this
778 process. It will be collected by wait shortly. */
779 thread = find_thread_ptid (ptid_build (pid, pid, 0));
780 thread->last_resume_kind = resume_stop;
bd99dc85 781 }
0d62e5e8 782
e3deef73
LM
783 if (linux_proc_get_tgid (pid) == pid)
784 {
785 DIR *dir;
786 char pathname[128];
787
788 sprintf (pathname, "/proc/%ld/task", pid);
789
790 dir = opendir (pathname);
791
792 if (!dir)
793 {
794 fprintf (stderr, "Could not open /proc/%ld/task.\n", pid);
795 fflush (stderr);
796 }
797 else
798 {
799 /* At this point we attached to the tgid. Scan the task for
800 existing threads. */
801 unsigned long lwp;
802 int new_threads_found;
803 int iterations = 0;
804 struct dirent *dp;
805
806 while (iterations < 2)
807 {
808 new_threads_found = 0;
809 /* Add all the other threads. While we go through the
810 threads, new threads may be spawned. Cycle through
811 the list of threads until we have done two iterations without
812 finding new threads. */
813 while ((dp = readdir (dir)) != NULL)
814 {
815 /* Fetch one lwp. */
816 lwp = strtoul (dp->d_name, NULL, 10);
817
818 /* Is this a new thread? */
819 if (lwp
820 && find_thread_ptid (ptid_build (pid, lwp, 0)) == NULL)
821 {
822 linux_attach_lwp_1 (lwp, 0);
823 new_threads_found++;
824
825 if (debug_threads)
87ce2a04
DE
826 debug_printf ("Found and attached to new lwp %ld\n",
827 lwp);
e3deef73
LM
828 }
829 }
830
831 if (!new_threads_found)
832 iterations++;
833 else
834 iterations = 0;
835
836 rewinddir (dir);
837 }
838 closedir (dir);
839 }
840 }
841
95954743
PA
842 return 0;
843}
844
845struct counter
846{
847 int pid;
848 int count;
849};
850
851static int
852second_thread_of_pid_p (struct inferior_list_entry *entry, void *args)
853{
854 struct counter *counter = args;
855
856 if (ptid_get_pid (entry->id) == counter->pid)
857 {
858 if (++counter->count > 1)
859 return 1;
860 }
d61ddec4 861
da6d8c04
DJ
862 return 0;
863}
864
95954743
PA
865static int
866last_thread_of_process_p (struct thread_info *thread)
867{
80894984 868 ptid_t ptid = thread->entry.id;
95954743
PA
869 int pid = ptid_get_pid (ptid);
870 struct counter counter = { pid , 0 };
da6d8c04 871
95954743
PA
872 return (find_inferior (&all_threads,
873 second_thread_of_pid_p, &counter) == NULL);
874}
875
da84f473
PA
876/* Kill LWP. */
877
878static void
879linux_kill_one_lwp (struct lwp_info *lwp)
880{
881 int pid = lwpid_of (lwp);
882
883 /* PTRACE_KILL is unreliable. After stepping into a signal handler,
884 there is no signal context, and ptrace(PTRACE_KILL) (or
885 ptrace(PTRACE_CONT, SIGKILL), pretty much the same) acts like
886 ptrace(CONT, pid, 0,0) and just resumes the tracee. A better
887 alternative is to kill with SIGKILL. We only need one SIGKILL
888 per process, not one for each thread. But since we still support
889 linuxthreads, and we also support debugging programs using raw
890 clone without CLONE_THREAD, we send one for each thread. For
891 years, we used PTRACE_KILL only, so we're being a bit paranoid
892 about some old kernels where PTRACE_KILL might work better
893 (dubious if there are any such, but that's why it's paranoia), so
894 we try SIGKILL first, PTRACE_KILL second, and so we're fine
895 everywhere. */
896
897 errno = 0;
898 kill (pid, SIGKILL);
899 if (debug_threads)
87ce2a04
DE
900 debug_printf ("LKL: kill (SIGKILL) %s, 0, 0 (%s)\n",
901 target_pid_to_str (ptid_of (lwp)),
902 errno ? strerror (errno) : "OK");
da84f473
PA
903
904 errno = 0;
b8e1b30e 905 ptrace (PTRACE_KILL, pid, (PTRACE_TYPE_ARG3) 0, (PTRACE_TYPE_ARG4) 0);
da84f473 906 if (debug_threads)
87ce2a04
DE
907 debug_printf ("LKL: PTRACE_KILL %s, 0, 0 (%s)\n",
908 target_pid_to_str (ptid_of (lwp)),
909 errno ? strerror (errno) : "OK");
da84f473
PA
910}
911
912/* Callback for `find_inferior'. Kills an lwp of a given process,
913 except the leader. */
95954743
PA
914
915static int
da84f473 916kill_one_lwp_callback (struct inferior_list_entry *entry, void *args)
da6d8c04 917{
0d62e5e8 918 struct thread_info *thread = (struct thread_info *) entry;
54a0b537 919 struct lwp_info *lwp = get_thread_lwp (thread);
0d62e5e8 920 int wstat;
95954743
PA
921 int pid = * (int *) args;
922
923 if (ptid_get_pid (entry->id) != pid)
924 return 0;
0d62e5e8 925
fd500816
DJ
926 /* We avoid killing the first thread here, because of a Linux kernel (at
927 least 2.6.0-test7 through 2.6.8-rc4) bug; if we kill the parent before
928 the children get a chance to be reaped, it will remain a zombie
929 forever. */
95954743 930
12b42a12 931 if (lwpid_of (lwp) == pid)
95954743
PA
932 {
933 if (debug_threads)
87ce2a04
DE
934 debug_printf ("lkop: is last of process %s\n",
935 target_pid_to_str (entry->id));
95954743
PA
936 return 0;
937 }
fd500816 938
0d62e5e8
DJ
939 do
940 {
da84f473 941 linux_kill_one_lwp (lwp);
0d62e5e8
DJ
942
943 /* Make sure it died. The loop is most likely unnecessary. */
80894984 944 pid = linux_wait_for_event (lwp->entry.id, &wstat, __WALL);
bd99dc85 945 } while (pid > 0 && WIFSTOPPED (wstat));
95954743
PA
946
947 return 0;
da6d8c04
DJ
948}
949
95954743
PA
950static int
951linux_kill (int pid)
0d62e5e8 952{
95954743 953 struct process_info *process;
54a0b537 954 struct lwp_info *lwp;
fd500816 955 int wstat;
95954743 956 int lwpid;
fd500816 957
95954743
PA
958 process = find_process_pid (pid);
959 if (process == NULL)
960 return -1;
9d606399 961
f9e39928
PA
962 /* If we're killing a running inferior, make sure it is stopped
963 first, as PTRACE_KILL will not work otherwise. */
7984d532 964 stop_all_lwps (0, NULL);
f9e39928 965
da84f473 966 find_inferior (&all_threads, kill_one_lwp_callback , &pid);
fd500816 967
54a0b537 968 /* See the comment in linux_kill_one_lwp. We did not kill the first
fd500816 969 thread in the list, so do so now. */
95954743 970 lwp = find_lwp_pid (pid_to_ptid (pid));
bd99dc85 971
784867a5 972 if (lwp == NULL)
fd500816 973 {
784867a5 974 if (debug_threads)
87ce2a04
DE
975 debug_printf ("lk_1: cannot find lwp %ld, for pid: %d\n",
976 lwpid_of (lwp), pid);
784867a5
JK
977 }
978 else
979 {
980 if (debug_threads)
87ce2a04
DE
981 debug_printf ("lk_1: killing lwp %ld, for pid: %d\n",
982 lwpid_of (lwp), pid);
fd500816 983
784867a5
JK
984 do
985 {
da84f473 986 linux_kill_one_lwp (lwp);
784867a5
JK
987
988 /* Make sure it died. The loop is most likely unnecessary. */
80894984 989 lwpid = linux_wait_for_event (lwp->entry.id, &wstat, __WALL);
784867a5
JK
990 } while (lwpid > 0 && WIFSTOPPED (wstat));
991 }
2d717e4f 992
8336d594 993 the_target->mourn (process);
f9e39928
PA
994
995 /* Since we presently can only stop all lwps of all processes, we
996 need to unstop lwps of other processes. */
7984d532 997 unstop_all_lwps (0, NULL);
95954743 998 return 0;
0d62e5e8
DJ
999}
1000
9b224c5e
PA
1001/* Get pending signal of THREAD, for detaching purposes. This is the
1002 signal the thread last stopped for, which we need to deliver to the
1003 thread when detaching, otherwise, it'd be suppressed/lost. */
1004
1005static int
1006get_detach_signal (struct thread_info *thread)
1007{
a493e3e2 1008 enum gdb_signal signo = GDB_SIGNAL_0;
9b224c5e
PA
1009 int status;
1010 struct lwp_info *lp = get_thread_lwp (thread);
1011
1012 if (lp->status_pending_p)
1013 status = lp->status_pending;
1014 else
1015 {
1016 /* If the thread had been suspended by gdbserver, and it stopped
1017 cleanly, then it'll have stopped with SIGSTOP. But we don't
1018 want to deliver that SIGSTOP. */
1019 if (thread->last_status.kind != TARGET_WAITKIND_STOPPED
a493e3e2 1020 || thread->last_status.value.sig == GDB_SIGNAL_0)
9b224c5e
PA
1021 return 0;
1022
1023 /* Otherwise, we may need to deliver the signal we
1024 intercepted. */
1025 status = lp->last_status;
1026 }
1027
1028 if (!WIFSTOPPED (status))
1029 {
1030 if (debug_threads)
87ce2a04
DE
1031 debug_printf ("GPS: lwp %s hasn't stopped: no pending signal\n",
1032 target_pid_to_str (ptid_of (lp)));
9b224c5e
PA
1033 return 0;
1034 }
1035
1036 /* Extended wait statuses aren't real SIGTRAPs. */
1037 if (WSTOPSIG (status) == SIGTRAP && status >> 16 != 0)
1038 {
1039 if (debug_threads)
87ce2a04
DE
1040 debug_printf ("GPS: lwp %s had stopped with extended "
1041 "status: no pending signal\n",
1042 target_pid_to_str (ptid_of (lp)));
9b224c5e
PA
1043 return 0;
1044 }
1045
2ea28649 1046 signo = gdb_signal_from_host (WSTOPSIG (status));
9b224c5e
PA
1047
1048 if (program_signals_p && !program_signals[signo])
1049 {
1050 if (debug_threads)
87ce2a04
DE
1051 debug_printf ("GPS: lwp %s had signal %s, but it is in nopass state\n",
1052 target_pid_to_str (ptid_of (lp)),
1053 gdb_signal_to_string (signo));
9b224c5e
PA
1054 return 0;
1055 }
1056 else if (!program_signals_p
1057 /* If we have no way to know which signals GDB does not
1058 want to have passed to the program, assume
1059 SIGTRAP/SIGINT, which is GDB's default. */
a493e3e2 1060 && (signo == GDB_SIGNAL_TRAP || signo == GDB_SIGNAL_INT))
9b224c5e
PA
1061 {
1062 if (debug_threads)
87ce2a04
DE
1063 debug_printf ("GPS: lwp %s had signal %s, "
1064 "but we don't know if we should pass it. "
1065 "Default to not.\n",
1066 target_pid_to_str (ptid_of (lp)),
1067 gdb_signal_to_string (signo));
9b224c5e
PA
1068 return 0;
1069 }
1070 else
1071 {
1072 if (debug_threads)
87ce2a04
DE
1073 debug_printf ("GPS: lwp %s has pending signal %s: delivering it.\n",
1074 target_pid_to_str (ptid_of (lp)),
1075 gdb_signal_to_string (signo));
9b224c5e
PA
1076
1077 return WSTOPSIG (status);
1078 }
1079}
1080
95954743
PA
1081static int
1082linux_detach_one_lwp (struct inferior_list_entry *entry, void *args)
6ad8ae5c
DJ
1083{
1084 struct thread_info *thread = (struct thread_info *) entry;
54a0b537 1085 struct lwp_info *lwp = get_thread_lwp (thread);
95954743 1086 int pid = * (int *) args;
9b224c5e 1087 int sig;
95954743
PA
1088
1089 if (ptid_get_pid (entry->id) != pid)
1090 return 0;
6ad8ae5c 1091
9b224c5e 1092 /* If there is a pending SIGSTOP, get rid of it. */
54a0b537 1093 if (lwp->stop_expected)
ae13219e 1094 {
9b224c5e 1095 if (debug_threads)
87ce2a04
DE
1096 debug_printf ("Sending SIGCONT to %s\n",
1097 target_pid_to_str (ptid_of (lwp)));
9b224c5e
PA
1098
1099 kill_lwp (lwpid_of (lwp), SIGCONT);
54a0b537 1100 lwp->stop_expected = 0;
ae13219e
DJ
1101 }
1102
1103 /* Flush any pending changes to the process's registers. */
3aee8918 1104 regcache_invalidate_thread (get_lwp_thread (lwp));
ae13219e 1105
9b224c5e
PA
1106 /* Pass on any pending signal for this thread. */
1107 sig = get_detach_signal (thread);
1108
ae13219e 1109 /* Finally, let it resume. */
82bfbe7e
PA
1110 if (the_low_target.prepare_to_resume != NULL)
1111 the_low_target.prepare_to_resume (lwp);
b8e1b30e
LM
1112 if (ptrace (PTRACE_DETACH, lwpid_of (lwp), (PTRACE_TYPE_ARG3) 0,
1113 (PTRACE_TYPE_ARG4) (long) sig) < 0)
9b224c5e
PA
1114 error (_("Can't detach %s: %s"),
1115 target_pid_to_str (ptid_of (lwp)),
1116 strerror (errno));
bd99dc85
PA
1117
1118 delete_lwp (lwp);
95954743 1119 return 0;
6ad8ae5c
DJ
1120}
1121
95954743
PA
1122static int
1123linux_detach (int pid)
1124{
1125 struct process_info *process;
1126
1127 process = find_process_pid (pid);
1128 if (process == NULL)
1129 return -1;
1130
f9e39928
PA
1131 /* Stop all threads before detaching. First, ptrace requires that
1132 the thread is stopped to sucessfully detach. Second, thread_db
1133 may need to uninstall thread event breakpoints from memory, which
1134 only works with a stopped process anyway. */
7984d532 1135 stop_all_lwps (0, NULL);
f9e39928 1136
ca5c370d 1137#ifdef USE_THREAD_DB
8336d594 1138 thread_db_detach (process);
ca5c370d
PA
1139#endif
1140
fa593d66
PA
1141 /* Stabilize threads (move out of jump pads). */
1142 stabilize_threads ();
1143
95954743 1144 find_inferior (&all_threads, linux_detach_one_lwp, &pid);
8336d594
PA
1145
1146 the_target->mourn (process);
f9e39928
PA
1147
1148 /* Since we presently can only stop all lwps of all processes, we
1149 need to unstop lwps of other processes. */
7984d532 1150 unstop_all_lwps (0, NULL);
f9e39928
PA
1151 return 0;
1152}
1153
1154/* Remove all LWPs that belong to process PROC from the lwp list. */
1155
1156static int
1157delete_lwp_callback (struct inferior_list_entry *entry, void *proc)
1158{
1159 struct lwp_info *lwp = (struct lwp_info *) entry;
1160 struct process_info *process = proc;
1161
1162 if (pid_of (lwp) == pid_of (process))
1163 delete_lwp (lwp);
1164
dd6953e1 1165 return 0;
6ad8ae5c
DJ
1166}
1167
8336d594
PA
1168static void
1169linux_mourn (struct process_info *process)
1170{
1171 struct process_info_private *priv;
1172
1173#ifdef USE_THREAD_DB
1174 thread_db_mourn (process);
1175#endif
1176
f9e39928
PA
1177 find_inferior (&all_lwps, delete_lwp_callback, process);
1178
8336d594
PA
1179 /* Freeing all private data. */
1180 priv = process->private;
1181 free (priv->arch_private);
1182 free (priv);
1183 process->private = NULL;
505106cd
PA
1184
1185 remove_process (process);
8336d594
PA
1186}
1187
444d6139 1188static void
95954743 1189linux_join (int pid)
444d6139 1190{
444d6139
PA
1191 int status, ret;
1192
1193 do {
95954743 1194 ret = my_waitpid (pid, &status, 0);
444d6139
PA
1195 if (WIFEXITED (status) || WIFSIGNALED (status))
1196 break;
1197 } while (ret != -1 || errno != ECHILD);
1198}
1199
6ad8ae5c 1200/* Return nonzero if the given thread is still alive. */
0d62e5e8 1201static int
95954743 1202linux_thread_alive (ptid_t ptid)
0d62e5e8 1203{
95954743
PA
1204 struct lwp_info *lwp = find_lwp_pid (ptid);
1205
1206 /* We assume we always know if a thread exits. If a whole process
1207 exited but we still haven't been able to report it to GDB, we'll
1208 hold on to the last lwp of the dead process. */
1209 if (lwp != NULL)
1210 return !lwp->dead;
0d62e5e8
DJ
1211 else
1212 return 0;
1213}
1214
6bf5e0ba 1215/* Return 1 if this lwp has an interesting status pending. */
611cb4a5 1216static int
d50171e4 1217status_pending_p_callback (struct inferior_list_entry *entry, void *arg)
0d62e5e8 1218{
54a0b537 1219 struct lwp_info *lwp = (struct lwp_info *) entry;
95954743 1220 ptid_t ptid = * (ptid_t *) arg;
7984d532 1221 struct thread_info *thread;
95954743
PA
1222
1223 /* Check if we're only interested in events from a specific process
1224 or its lwps. */
1225 if (!ptid_equal (minus_one_ptid, ptid)
80894984 1226 && ptid_get_pid (ptid) != ptid_get_pid (lwp->entry.id))
95954743 1227 return 0;
0d62e5e8 1228
d50171e4
PA
1229 thread = get_lwp_thread (lwp);
1230
1231 /* If we got a `vCont;t', but we haven't reported a stop yet, do
1232 report any status pending the LWP may have. */
8336d594 1233 if (thread->last_resume_kind == resume_stop
7984d532 1234 && thread->last_status.kind != TARGET_WAITKIND_IGNORE)
d50171e4 1235 return 0;
0d62e5e8 1236
d50171e4 1237 return lwp->status_pending_p;
0d62e5e8
DJ
1238}
1239
95954743
PA
1240static int
1241same_lwp (struct inferior_list_entry *entry, void *data)
1242{
1243 ptid_t ptid = *(ptid_t *) data;
1244 int lwp;
1245
1246 if (ptid_get_lwp (ptid) != 0)
1247 lwp = ptid_get_lwp (ptid);
1248 else
1249 lwp = ptid_get_pid (ptid);
1250
1251 if (ptid_get_lwp (entry->id) == lwp)
1252 return 1;
1253
1254 return 0;
1255}
1256
1257struct lwp_info *
1258find_lwp_pid (ptid_t ptid)
1259{
1260 return (struct lwp_info*) find_inferior (&all_lwps, same_lwp, &ptid);
1261}
1262
bd99dc85 1263static struct lwp_info *
95954743 1264linux_wait_for_lwp (ptid_t ptid, int *wstatp, int options)
611cb4a5 1265{
0d62e5e8 1266 int ret;
95954743 1267 int to_wait_for = -1;
bd99dc85 1268 struct lwp_info *child = NULL;
0d62e5e8 1269
bd99dc85 1270 if (debug_threads)
87ce2a04 1271 debug_printf ("linux_wait_for_lwp: %s\n", target_pid_to_str (ptid));
95954743
PA
1272
1273 if (ptid_equal (ptid, minus_one_ptid))
1274 to_wait_for = -1; /* any child */
1275 else
1276 to_wait_for = ptid_get_lwp (ptid); /* this lwp only */
0d62e5e8 1277
bd99dc85 1278 options |= __WALL;
0d62e5e8 1279
bd99dc85 1280retry:
0d62e5e8 1281
bd99dc85
PA
1282 ret = my_waitpid (to_wait_for, wstatp, options);
1283 if (ret == 0 || (ret == -1 && errno == ECHILD && (options & WNOHANG)))
1284 return NULL;
1285 else if (ret == -1)
1286 perror_with_name ("waitpid");
0d62e5e8
DJ
1287
1288 if (debug_threads
1289 && (!WIFSTOPPED (*wstatp)
1290 || (WSTOPSIG (*wstatp) != 32
1291 && WSTOPSIG (*wstatp) != 33)))
87ce2a04 1292 debug_printf ("Got an event from %d (%x)\n", ret, *wstatp);
0d62e5e8 1293
95954743 1294 child = find_lwp_pid (pid_to_ptid (ret));
0d62e5e8 1295
24a09b5f
DJ
1296 /* If we didn't find a process, one of two things presumably happened:
1297 - A process we started and then detached from has exited. Ignore it.
1298 - A process we are controlling has forked and the new child's stop
1299 was reported to us by the kernel. Save its PID. */
bd99dc85 1300 if (child == NULL && WIFSTOPPED (*wstatp))
24a09b5f 1301 {
05044653 1302 add_to_pid_list (&stopped_pids, ret, *wstatp);
24a09b5f
DJ
1303 goto retry;
1304 }
bd99dc85 1305 else if (child == NULL)
24a09b5f
DJ
1306 goto retry;
1307
bd99dc85 1308 child->stopped = 1;
0d62e5e8 1309
bd99dc85 1310 child->last_status = *wstatp;
32ca6d61 1311
3aee8918 1312 if (WIFSTOPPED (*wstatp))
d61ddec4 1313 {
3aee8918
PA
1314 struct process_info *proc;
1315
1316 /* Architecture-specific setup after inferior is running. This
1317 needs to happen after we have attached to the inferior and it
1318 is stopped for the first time, but before we access any
1319 inferior registers. */
1320 proc = find_process_pid (pid_of (child));
1321 if (proc->private->new_inferior)
1322 {
1323 struct thread_info *saved_inferior;
1324
1325 saved_inferior = current_inferior;
1326 current_inferior = get_lwp_thread (child);
1327
1328 the_low_target.arch_setup ();
1329
1330 current_inferior = saved_inferior;
1331
1332 proc->private->new_inferior = 0;
1333 }
d61ddec4
UW
1334 }
1335
c3adc08c
PA
1336 /* Fetch the possibly triggered data watchpoint info and store it in
1337 CHILD.
1338
1339 On some archs, like x86, that use debug registers to set
1340 watchpoints, it's possible that the way to know which watched
1341 address trapped, is to check the register that is used to select
1342 which address to watch. Problem is, between setting the
1343 watchpoint and reading back which data address trapped, the user
1344 may change the set of watchpoints, and, as a consequence, GDB
1345 changes the debug registers in the inferior. To avoid reading
1346 back a stale stopped-data-address when that happens, we cache in
1347 LP the fact that a watchpoint trapped, and the corresponding data
1348 address, as soon as we see CHILD stop with a SIGTRAP. If GDB
1349 changes the debug registers meanwhile, we have the cached data we
1350 can rely on. */
1351
1352 if (WIFSTOPPED (*wstatp) && WSTOPSIG (*wstatp) == SIGTRAP)
1353 {
1354 if (the_low_target.stopped_by_watchpoint == NULL)
1355 {
1356 child->stopped_by_watchpoint = 0;
1357 }
1358 else
1359 {
1360 struct thread_info *saved_inferior;
1361
1362 saved_inferior = current_inferior;
1363 current_inferior = get_lwp_thread (child);
1364
1365 child->stopped_by_watchpoint
1366 = the_low_target.stopped_by_watchpoint ();
1367
1368 if (child->stopped_by_watchpoint)
1369 {
1370 if (the_low_target.stopped_data_address != NULL)
1371 child->stopped_data_address
1372 = the_low_target.stopped_data_address ();
1373 else
1374 child->stopped_data_address = 0;
1375 }
1376
1377 current_inferior = saved_inferior;
1378 }
1379 }
1380
d50171e4
PA
1381 /* Store the STOP_PC, with adjustment applied. This depends on the
1382 architecture being defined already (so that CHILD has a valid
1383 regcache), and on LAST_STATUS being set (to check for SIGTRAP or
1384 not). */
1385 if (WIFSTOPPED (*wstatp))
1386 child->stop_pc = get_stop_pc (child);
1387
0d62e5e8 1388 if (debug_threads
47c0c975
DE
1389 && WIFSTOPPED (*wstatp)
1390 && the_low_target.get_pc != NULL)
0d62e5e8 1391 {
896c7fbb 1392 struct thread_info *saved_inferior = current_inferior;
bce522a2 1393 struct regcache *regcache;
47c0c975
DE
1394 CORE_ADDR pc;
1395
d50171e4 1396 current_inferior = get_lwp_thread (child);
bce522a2 1397 regcache = get_thread_regcache (current_inferior, 1);
442ea881 1398 pc = (*the_low_target.get_pc) (regcache);
87ce2a04 1399 debug_printf ("linux_wait_for_lwp: pc is 0x%lx\n", (long) pc);
896c7fbb 1400 current_inferior = saved_inferior;
0d62e5e8 1401 }
bd99dc85
PA
1402
1403 return child;
0d62e5e8 1404}
611cb4a5 1405
219f2f23
PA
1406/* This function should only be called if the LWP got a SIGTRAP.
1407
1408 Handle any tracepoint steps or hits. Return true if a tracepoint
1409 event was handled, 0 otherwise. */
1410
1411static int
1412handle_tracepoints (struct lwp_info *lwp)
1413{
1414 struct thread_info *tinfo = get_lwp_thread (lwp);
1415 int tpoint_related_event = 0;
1416
7984d532
PA
1417 /* If this tracepoint hit causes a tracing stop, we'll immediately
1418 uninsert tracepoints. To do this, we temporarily pause all
1419 threads, unpatch away, and then unpause threads. We need to make
1420 sure the unpausing doesn't resume LWP too. */
1421 lwp->suspended++;
1422
219f2f23
PA
1423 /* And we need to be sure that any all-threads-stopping doesn't try
1424 to move threads out of the jump pads, as it could deadlock the
1425 inferior (LWP could be in the jump pad, maybe even holding the
1426 lock.) */
1427
1428 /* Do any necessary step collect actions. */
1429 tpoint_related_event |= tracepoint_finished_step (tinfo, lwp->stop_pc);
1430
fa593d66
PA
1431 tpoint_related_event |= handle_tracepoint_bkpts (tinfo, lwp->stop_pc);
1432
219f2f23
PA
1433 /* See if we just hit a tracepoint and do its main collect
1434 actions. */
1435 tpoint_related_event |= tracepoint_was_hit (tinfo, lwp->stop_pc);
1436
7984d532
PA
1437 lwp->suspended--;
1438
1439 gdb_assert (lwp->suspended == 0);
fa593d66 1440 gdb_assert (!stabilizing_threads || lwp->collecting_fast_tracepoint);
7984d532 1441
219f2f23
PA
1442 if (tpoint_related_event)
1443 {
1444 if (debug_threads)
87ce2a04 1445 debug_printf ("got a tracepoint event\n");
219f2f23
PA
1446 return 1;
1447 }
1448
1449 return 0;
1450}
1451
fa593d66
PA
1452/* Convenience wrapper. Returns true if LWP is presently collecting a
1453 fast tracepoint. */
1454
1455static int
1456linux_fast_tracepoint_collecting (struct lwp_info *lwp,
1457 struct fast_tpoint_collect_status *status)
1458{
1459 CORE_ADDR thread_area;
1460
1461 if (the_low_target.get_thread_area == NULL)
1462 return 0;
1463
1464 /* Get the thread area address. This is used to recognize which
1465 thread is which when tracing with the in-process agent library.
1466 We don't read anything from the address, and treat it as opaque;
1467 it's the address itself that we assume is unique per-thread. */
1468 if ((*the_low_target.get_thread_area) (lwpid_of (lwp), &thread_area) == -1)
1469 return 0;
1470
1471 return fast_tracepoint_collecting (thread_area, lwp->stop_pc, status);
1472}
1473
1474/* The reason we resume in the caller, is because we want to be able
1475 to pass lwp->status_pending as WSTAT, and we need to clear
1476 status_pending_p before resuming, otherwise, linux_resume_one_lwp
1477 refuses to resume. */
1478
1479static int
1480maybe_move_out_of_jump_pad (struct lwp_info *lwp, int *wstat)
1481{
1482 struct thread_info *saved_inferior;
1483
1484 saved_inferior = current_inferior;
1485 current_inferior = get_lwp_thread (lwp);
1486
1487 if ((wstat == NULL
1488 || (WIFSTOPPED (*wstat) && WSTOPSIG (*wstat) != SIGTRAP))
1489 && supports_fast_tracepoints ()
58b4daa5 1490 && agent_loaded_p ())
fa593d66
PA
1491 {
1492 struct fast_tpoint_collect_status status;
1493 int r;
1494
1495 if (debug_threads)
87ce2a04
DE
1496 debug_printf ("Checking whether LWP %ld needs to move out of the "
1497 "jump pad.\n",
1498 lwpid_of (lwp));
fa593d66
PA
1499
1500 r = linux_fast_tracepoint_collecting (lwp, &status);
1501
1502 if (wstat == NULL
1503 || (WSTOPSIG (*wstat) != SIGILL
1504 && WSTOPSIG (*wstat) != SIGFPE
1505 && WSTOPSIG (*wstat) != SIGSEGV
1506 && WSTOPSIG (*wstat) != SIGBUS))
1507 {
1508 lwp->collecting_fast_tracepoint = r;
1509
1510 if (r != 0)
1511 {
1512 if (r == 1 && lwp->exit_jump_pad_bkpt == NULL)
1513 {
1514 /* Haven't executed the original instruction yet.
1515 Set breakpoint there, and wait till it's hit,
1516 then single-step until exiting the jump pad. */
1517 lwp->exit_jump_pad_bkpt
1518 = set_breakpoint_at (status.adjusted_insn_addr, NULL);
1519 }
1520
1521 if (debug_threads)
87ce2a04
DE
1522 debug_printf ("Checking whether LWP %ld needs to move out of "
1523 "the jump pad...it does\n",
1524 lwpid_of (lwp));
0cccb683 1525 current_inferior = saved_inferior;
fa593d66
PA
1526
1527 return 1;
1528 }
1529 }
1530 else
1531 {
1532 /* If we get a synchronous signal while collecting, *and*
1533 while executing the (relocated) original instruction,
1534 reset the PC to point at the tpoint address, before
1535 reporting to GDB. Otherwise, it's an IPA lib bug: just
1536 report the signal to GDB, and pray for the best. */
1537
1538 lwp->collecting_fast_tracepoint = 0;
1539
1540 if (r != 0
1541 && (status.adjusted_insn_addr <= lwp->stop_pc
1542 && lwp->stop_pc < status.adjusted_insn_addr_end))
1543 {
1544 siginfo_t info;
1545 struct regcache *regcache;
1546
1547 /* The si_addr on a few signals references the address
1548 of the faulting instruction. Adjust that as
1549 well. */
1550 if ((WSTOPSIG (*wstat) == SIGILL
1551 || WSTOPSIG (*wstat) == SIGFPE
1552 || WSTOPSIG (*wstat) == SIGBUS
1553 || WSTOPSIG (*wstat) == SIGSEGV)
56f7af9c 1554 && ptrace (PTRACE_GETSIGINFO, lwpid_of (lwp),
b8e1b30e 1555 (PTRACE_TYPE_ARG3) 0, &info) == 0
fa593d66
PA
1556 /* Final check just to make sure we don't clobber
1557 the siginfo of non-kernel-sent signals. */
1558 && (uintptr_t) info.si_addr == lwp->stop_pc)
1559 {
1560 info.si_addr = (void *) (uintptr_t) status.tpoint_addr;
56f7af9c 1561 ptrace (PTRACE_SETSIGINFO, lwpid_of (lwp),
b8e1b30e 1562 (PTRACE_TYPE_ARG3) 0, &info);
fa593d66
PA
1563 }
1564
1565 regcache = get_thread_regcache (get_lwp_thread (lwp), 1);
1566 (*the_low_target.set_pc) (regcache, status.tpoint_addr);
1567 lwp->stop_pc = status.tpoint_addr;
1568
1569 /* Cancel any fast tracepoint lock this thread was
1570 holding. */
1571 force_unlock_trace_buffer ();
1572 }
1573
1574 if (lwp->exit_jump_pad_bkpt != NULL)
1575 {
1576 if (debug_threads)
87ce2a04
DE
1577 debug_printf ("Cancelling fast exit-jump-pad: removing bkpt. "
1578 "stopping all threads momentarily.\n");
fa593d66
PA
1579
1580 stop_all_lwps (1, lwp);
1581 cancel_breakpoints ();
1582
1583 delete_breakpoint (lwp->exit_jump_pad_bkpt);
1584 lwp->exit_jump_pad_bkpt = NULL;
1585
1586 unstop_all_lwps (1, lwp);
1587
1588 gdb_assert (lwp->suspended >= 0);
1589 }
1590 }
1591 }
1592
1593 if (debug_threads)
87ce2a04
DE
1594 debug_printf ("Checking whether LWP %ld needs to move out of the "
1595 "jump pad...no\n",
1596 lwpid_of (lwp));
0cccb683
YQ
1597
1598 current_inferior = saved_inferior;
fa593d66
PA
1599 return 0;
1600}
1601
1602/* Enqueue one signal in the "signals to report later when out of the
1603 jump pad" list. */
1604
1605static void
1606enqueue_one_deferred_signal (struct lwp_info *lwp, int *wstat)
1607{
1608 struct pending_signals *p_sig;
1609
1610 if (debug_threads)
87ce2a04
DE
1611 debug_printf ("Deferring signal %d for LWP %ld.\n",
1612 WSTOPSIG (*wstat), lwpid_of (lwp));
fa593d66
PA
1613
1614 if (debug_threads)
1615 {
1616 struct pending_signals *sig;
1617
1618 for (sig = lwp->pending_signals_to_report;
1619 sig != NULL;
1620 sig = sig->prev)
87ce2a04
DE
1621 debug_printf (" Already queued %d\n",
1622 sig->signal);
fa593d66 1623
87ce2a04 1624 debug_printf (" (no more currently queued signals)\n");
fa593d66
PA
1625 }
1626
1a981360
PA
1627 /* Don't enqueue non-RT signals if they are already in the deferred
1628 queue. (SIGSTOP being the easiest signal to see ending up here
1629 twice) */
1630 if (WSTOPSIG (*wstat) < __SIGRTMIN)
1631 {
1632 struct pending_signals *sig;
1633
1634 for (sig = lwp->pending_signals_to_report;
1635 sig != NULL;
1636 sig = sig->prev)
1637 {
1638 if (sig->signal == WSTOPSIG (*wstat))
1639 {
1640 if (debug_threads)
87ce2a04
DE
1641 debug_printf ("Not requeuing already queued non-RT signal %d"
1642 " for LWP %ld\n",
1643 sig->signal,
1644 lwpid_of (lwp));
1a981360
PA
1645 return;
1646 }
1647 }
1648 }
1649
fa593d66
PA
1650 p_sig = xmalloc (sizeof (*p_sig));
1651 p_sig->prev = lwp->pending_signals_to_report;
1652 p_sig->signal = WSTOPSIG (*wstat);
1653 memset (&p_sig->info, 0, sizeof (siginfo_t));
b8e1b30e 1654 ptrace (PTRACE_GETSIGINFO, lwpid_of (lwp), (PTRACE_TYPE_ARG3) 0,
56f7af9c 1655 &p_sig->info);
fa593d66
PA
1656
1657 lwp->pending_signals_to_report = p_sig;
1658}
1659
1660/* Dequeue one signal from the "signals to report later when out of
1661 the jump pad" list. */
1662
1663static int
1664dequeue_one_deferred_signal (struct lwp_info *lwp, int *wstat)
1665{
1666 if (lwp->pending_signals_to_report != NULL)
1667 {
1668 struct pending_signals **p_sig;
1669
1670 p_sig = &lwp->pending_signals_to_report;
1671 while ((*p_sig)->prev != NULL)
1672 p_sig = &(*p_sig)->prev;
1673
1674 *wstat = W_STOPCODE ((*p_sig)->signal);
1675 if ((*p_sig)->info.si_signo != 0)
b8e1b30e 1676 ptrace (PTRACE_SETSIGINFO, lwpid_of (lwp), (PTRACE_TYPE_ARG3) 0,
56f7af9c 1677 &(*p_sig)->info);
fa593d66
PA
1678 free (*p_sig);
1679 *p_sig = NULL;
1680
1681 if (debug_threads)
87ce2a04
DE
1682 debug_printf ("Reporting deferred signal %d for LWP %ld.\n",
1683 WSTOPSIG (*wstat), lwpid_of (lwp));
fa593d66
PA
1684
1685 if (debug_threads)
1686 {
1687 struct pending_signals *sig;
1688
1689 for (sig = lwp->pending_signals_to_report;
1690 sig != NULL;
1691 sig = sig->prev)
87ce2a04
DE
1692 debug_printf (" Still queued %d\n",
1693 sig->signal);
fa593d66 1694
87ce2a04 1695 debug_printf (" (no more queued signals)\n");
fa593d66
PA
1696 }
1697
1698 return 1;
1699 }
1700
1701 return 0;
1702}
1703
d50171e4
PA
1704/* Arrange for a breakpoint to be hit again later. We don't keep the
1705 SIGTRAP status and don't forward the SIGTRAP signal to the LWP. We
1706 will handle the current event, eventually we will resume this LWP,
1707 and this breakpoint will trap again. */
1708
1709static int
1710cancel_breakpoint (struct lwp_info *lwp)
1711{
1712 struct thread_info *saved_inferior;
d50171e4
PA
1713
1714 /* There's nothing to do if we don't support breakpoints. */
1715 if (!supports_breakpoints ())
1716 return 0;
1717
d50171e4
PA
1718 /* breakpoint_at reads from current inferior. */
1719 saved_inferior = current_inferior;
1720 current_inferior = get_lwp_thread (lwp);
1721
1722 if ((*the_low_target.breakpoint_at) (lwp->stop_pc))
1723 {
1724 if (debug_threads)
87ce2a04
DE
1725 debug_printf ("CB: Push back breakpoint for %s\n",
1726 target_pid_to_str (ptid_of (lwp)));
d50171e4
PA
1727
1728 /* Back up the PC if necessary. */
1729 if (the_low_target.decr_pc_after_break)
1730 {
1731 struct regcache *regcache
fc7238bb 1732 = get_thread_regcache (current_inferior, 1);
d50171e4
PA
1733 (*the_low_target.set_pc) (regcache, lwp->stop_pc);
1734 }
1735
1736 current_inferior = saved_inferior;
1737 return 1;
1738 }
1739 else
1740 {
1741 if (debug_threads)
87ce2a04
DE
1742 debug_printf ("CB: No breakpoint found at %s for [%s]\n",
1743 paddress (lwp->stop_pc),
1744 target_pid_to_str (ptid_of (lwp)));
d50171e4
PA
1745 }
1746
1747 current_inferior = saved_inferior;
1748 return 0;
1749}
1750
1751/* When the event-loop is doing a step-over, this points at the thread
1752 being stepped. */
1753ptid_t step_over_bkpt;
1754
bd99dc85
PA
1755/* Wait for an event from child PID. If PID is -1, wait for any
1756 child. Store the stop status through the status pointer WSTAT.
1757 OPTIONS is passed to the waitpid call. Return 0 if no child stop
1758 event was found and OPTIONS contains WNOHANG. Return the PID of
ee1e2d4f 1759 the stopped child and update current_inferior otherwise. */
bd99dc85 1760
0d62e5e8 1761static int
d8301ad1 1762linux_wait_for_event (ptid_t ptid, int *wstat, int options)
0d62e5e8 1763{
d50171e4 1764 struct lwp_info *event_child, *requested_child;
d8301ad1 1765 ptid_t wait_ptid;
d50171e4 1766
d50171e4
PA
1767 event_child = NULL;
1768 requested_child = NULL;
0d62e5e8 1769
95954743 1770 /* Check for a lwp with a pending status. */
bd99dc85 1771
e825046f 1772 if (ptid_equal (ptid, minus_one_ptid) || ptid_is_pid (ptid))
0d62e5e8 1773 {
54a0b537 1774 event_child = (struct lwp_info *)
d50171e4 1775 find_inferior (&all_lwps, status_pending_p_callback, &ptid);
0d62e5e8 1776 if (debug_threads && event_child)
87ce2a04 1777 debug_printf ("Got a pending child %ld\n", lwpid_of (event_child));
0d62e5e8
DJ
1778 }
1779 else
1780 {
95954743 1781 requested_child = find_lwp_pid (ptid);
d50171e4 1782
bde24c0a 1783 if (stopping_threads == NOT_STOPPING_THREADS
fa593d66
PA
1784 && requested_child->status_pending_p
1785 && requested_child->collecting_fast_tracepoint)
1786 {
1787 enqueue_one_deferred_signal (requested_child,
1788 &requested_child->status_pending);
1789 requested_child->status_pending_p = 0;
1790 requested_child->status_pending = 0;
1791 linux_resume_one_lwp (requested_child, 0, 0, NULL);
1792 }
1793
1794 if (requested_child->suspended
1795 && requested_child->status_pending_p)
1796 fatal ("requesting an event out of a suspended child?");
1797
d50171e4 1798 if (requested_child->status_pending_p)
bd99dc85 1799 event_child = requested_child;
0d62e5e8 1800 }
611cb4a5 1801
0d62e5e8
DJ
1802 if (event_child != NULL)
1803 {
bd99dc85 1804 if (debug_threads)
87ce2a04
DE
1805 debug_printf ("Got an event from pending child %ld (%04x)\n",
1806 lwpid_of (event_child), event_child->status_pending);
bd99dc85
PA
1807 *wstat = event_child->status_pending;
1808 event_child->status_pending_p = 0;
1809 event_child->status_pending = 0;
1810 current_inferior = get_lwp_thread (event_child);
1811 return lwpid_of (event_child);
0d62e5e8
DJ
1812 }
1813
d8301ad1
JK
1814 if (ptid_is_pid (ptid))
1815 {
1816 /* A request to wait for a specific tgid. This is not possible
1817 with waitpid, so instead, we wait for any child, and leave
1818 children we're not interested in right now with a pending
1819 status to report later. */
1820 wait_ptid = minus_one_ptid;
1821 }
1822 else
1823 wait_ptid = ptid;
1824
0d62e5e8
DJ
1825 /* We only enter this loop if no process has a pending wait status. Thus
1826 any action taken in response to a wait status inside this loop is
1827 responding as soon as we detect the status, not after any pending
1828 events. */
1829 while (1)
1830 {
d8301ad1 1831 event_child = linux_wait_for_lwp (wait_ptid, wstat, options);
0d62e5e8 1832
bd99dc85 1833 if ((options & WNOHANG) && event_child == NULL)
d50171e4
PA
1834 {
1835 if (debug_threads)
87ce2a04 1836 debug_printf ("WNOHANG set, no event found\n");
d50171e4
PA
1837 return 0;
1838 }
0d62e5e8
DJ
1839
1840 if (event_child == NULL)
1841 error ("event from unknown child");
611cb4a5 1842
d8301ad1
JK
1843 if (ptid_is_pid (ptid)
1844 && ptid_get_pid (ptid) != ptid_get_pid (ptid_of (event_child)))
1845 {
1846 if (! WIFSTOPPED (*wstat))
1847 mark_lwp_dead (event_child, *wstat);
1848 else
1849 {
1850 event_child->status_pending_p = 1;
1851 event_child->status_pending = *wstat;
1852 }
1853 continue;
1854 }
1855
bd99dc85 1856 current_inferior = get_lwp_thread (event_child);
0d62e5e8 1857
89be2091 1858 /* Check for thread exit. */
bd99dc85 1859 if (! WIFSTOPPED (*wstat))
0d62e5e8 1860 {
89be2091 1861 if (debug_threads)
87ce2a04 1862 debug_printf ("LWP %ld exiting\n", lwpid_of (event_child));
89be2091
DJ
1863
1864 /* If the last thread is exiting, just return. */
95954743 1865 if (last_thread_of_process_p (current_inferior))
bd99dc85
PA
1866 {
1867 if (debug_threads)
87ce2a04
DE
1868 debug_printf ("LWP %ld is last lwp of process\n",
1869 lwpid_of (event_child));
bd99dc85
PA
1870 return lwpid_of (event_child);
1871 }
89be2091 1872
bd99dc85
PA
1873 if (!non_stop)
1874 {
649ebbca 1875 current_inferior = get_first_thread ();
bd99dc85 1876 if (debug_threads)
87ce2a04
DE
1877 debug_printf ("Current inferior is now %ld\n",
1878 lwpid_of (get_thread_lwp (current_inferior)));
bd99dc85
PA
1879 }
1880 else
1881 {
1882 current_inferior = NULL;
1883 if (debug_threads)
87ce2a04 1884 debug_printf ("Current inferior is now <NULL>\n");
bd99dc85 1885 }
89be2091
DJ
1886
1887 /* If we were waiting for this particular child to do something...
1888 well, it did something. */
bd99dc85 1889 if (requested_child != NULL)
d50171e4
PA
1890 {
1891 int lwpid = lwpid_of (event_child);
1892
1893 /* Cancel the step-over operation --- the thread that
1894 started it is gone. */
1895 if (finish_step_over (event_child))
7984d532 1896 unstop_all_lwps (1, event_child);
d50171e4
PA
1897 delete_lwp (event_child);
1898 return lwpid;
1899 }
1900
1901 delete_lwp (event_child);
89be2091
DJ
1902
1903 /* Wait for a more interesting event. */
1904 continue;
1905 }
1906
a6dbe5df
PA
1907 if (event_child->must_set_ptrace_flags)
1908 {
1e7fc18c 1909 linux_enable_event_reporting (lwpid_of (event_child));
a6dbe5df
PA
1910 event_child->must_set_ptrace_flags = 0;
1911 }
1912
bd99dc85
PA
1913 if (WIFSTOPPED (*wstat) && WSTOPSIG (*wstat) == SIGTRAP
1914 && *wstat >> 16 != 0)
24a09b5f 1915 {
bd99dc85 1916 handle_extended_wait (event_child, *wstat);
24a09b5f
DJ
1917 continue;
1918 }
1919
d50171e4
PA
1920 if (WIFSTOPPED (*wstat)
1921 && WSTOPSIG (*wstat) == SIGSTOP
1922 && event_child->stop_expected)
1923 {
1924 int should_stop;
1925
1926 if (debug_threads)
87ce2a04 1927 debug_printf ("Expected stop.\n");
d50171e4
PA
1928 event_child->stop_expected = 0;
1929
8336d594 1930 should_stop = (current_inferior->last_resume_kind == resume_stop
bde24c0a 1931 || stopping_threads != NOT_STOPPING_THREADS);
d50171e4
PA
1932
1933 if (!should_stop)
1934 {
1935 linux_resume_one_lwp (event_child,
1936 event_child->stepping, 0, NULL);
1937 continue;
1938 }
1939 }
1940
bd99dc85 1941 return lwpid_of (event_child);
611cb4a5 1942 }
0d62e5e8 1943
611cb4a5
DJ
1944 /* NOTREACHED */
1945 return 0;
1946}
1947
6bf5e0ba
PA
1948/* Count the LWP's that have had events. */
1949
1950static int
1951count_events_callback (struct inferior_list_entry *entry, void *data)
1952{
1953 struct lwp_info *lp = (struct lwp_info *) entry;
8336d594 1954 struct thread_info *thread = get_lwp_thread (lp);
6bf5e0ba
PA
1955 int *count = data;
1956
1957 gdb_assert (count != NULL);
1958
1959 /* Count only resumed LWPs that have a SIGTRAP event pending that
1960 should be reported to GDB. */
8336d594
PA
1961 if (thread->last_status.kind == TARGET_WAITKIND_IGNORE
1962 && thread->last_resume_kind != resume_stop
6bf5e0ba
PA
1963 && lp->status_pending_p
1964 && WIFSTOPPED (lp->status_pending)
1965 && WSTOPSIG (lp->status_pending) == SIGTRAP
1966 && !breakpoint_inserted_here (lp->stop_pc))
1967 (*count)++;
1968
1969 return 0;
1970}
1971
1972/* Select the LWP (if any) that is currently being single-stepped. */
1973
1974static int
1975select_singlestep_lwp_callback (struct inferior_list_entry *entry, void *data)
1976{
1977 struct lwp_info *lp = (struct lwp_info *) entry;
8336d594 1978 struct thread_info *thread = get_lwp_thread (lp);
6bf5e0ba 1979
8336d594
PA
1980 if (thread->last_status.kind == TARGET_WAITKIND_IGNORE
1981 && thread->last_resume_kind == resume_step
6bf5e0ba
PA
1982 && lp->status_pending_p)
1983 return 1;
1984 else
1985 return 0;
1986}
1987
1988/* Select the Nth LWP that has had a SIGTRAP event that should be
1989 reported to GDB. */
1990
1991static int
1992select_event_lwp_callback (struct inferior_list_entry *entry, void *data)
1993{
1994 struct lwp_info *lp = (struct lwp_info *) entry;
8336d594 1995 struct thread_info *thread = get_lwp_thread (lp);
6bf5e0ba
PA
1996 int *selector = data;
1997
1998 gdb_assert (selector != NULL);
1999
2000 /* Select only resumed LWPs that have a SIGTRAP event pending. */
8336d594
PA
2001 if (thread->last_resume_kind != resume_stop
2002 && thread->last_status.kind == TARGET_WAITKIND_IGNORE
6bf5e0ba
PA
2003 && lp->status_pending_p
2004 && WIFSTOPPED (lp->status_pending)
2005 && WSTOPSIG (lp->status_pending) == SIGTRAP
2006 && !breakpoint_inserted_here (lp->stop_pc))
2007 if ((*selector)-- == 0)
2008 return 1;
2009
2010 return 0;
2011}
2012
2013static int
2014cancel_breakpoints_callback (struct inferior_list_entry *entry, void *data)
2015{
2016 struct lwp_info *lp = (struct lwp_info *) entry;
8336d594 2017 struct thread_info *thread = get_lwp_thread (lp);
6bf5e0ba
PA
2018 struct lwp_info *event_lp = data;
2019
2020 /* Leave the LWP that has been elected to receive a SIGTRAP alone. */
2021 if (lp == event_lp)
2022 return 0;
2023
2024 /* If a LWP other than the LWP that we're reporting an event for has
2025 hit a GDB breakpoint (as opposed to some random trap signal),
2026 then just arrange for it to hit it again later. We don't keep
2027 the SIGTRAP status and don't forward the SIGTRAP signal to the
2028 LWP. We will handle the current event, eventually we will resume
2029 all LWPs, and this one will get its breakpoint trap again.
2030
2031 If we do not do this, then we run the risk that the user will
2032 delete or disable the breakpoint, but the LWP will have already
2033 tripped on it. */
2034
8336d594
PA
2035 if (thread->last_resume_kind != resume_stop
2036 && thread->last_status.kind == TARGET_WAITKIND_IGNORE
6bf5e0ba
PA
2037 && lp->status_pending_p
2038 && WIFSTOPPED (lp->status_pending)
2039 && WSTOPSIG (lp->status_pending) == SIGTRAP
bdabb078
PA
2040 && !lp->stepping
2041 && !lp->stopped_by_watchpoint
6bf5e0ba
PA
2042 && cancel_breakpoint (lp))
2043 /* Throw away the SIGTRAP. */
2044 lp->status_pending_p = 0;
2045
2046 return 0;
2047}
2048
7984d532
PA
2049static void
2050linux_cancel_breakpoints (void)
2051{
2052 find_inferior (&all_lwps, cancel_breakpoints_callback, NULL);
2053}
2054
6bf5e0ba
PA
2055/* Select one LWP out of those that have events pending. */
2056
2057static void
2058select_event_lwp (struct lwp_info **orig_lp)
2059{
2060 int num_events = 0;
2061 int random_selector;
2062 struct lwp_info *event_lp;
2063
2064 /* Give preference to any LWP that is being single-stepped. */
2065 event_lp
2066 = (struct lwp_info *) find_inferior (&all_lwps,
2067 select_singlestep_lwp_callback, NULL);
2068 if (event_lp != NULL)
2069 {
2070 if (debug_threads)
87ce2a04
DE
2071 debug_printf ("SEL: Select single-step %s\n",
2072 target_pid_to_str (ptid_of (event_lp)));
6bf5e0ba
PA
2073 }
2074 else
2075 {
2076 /* No single-stepping LWP. Select one at random, out of those
2077 which have had SIGTRAP events. */
2078
2079 /* First see how many SIGTRAP events we have. */
2080 find_inferior (&all_lwps, count_events_callback, &num_events);
2081
2082 /* Now randomly pick a LWP out of those that have had a SIGTRAP. */
2083 random_selector = (int)
2084 ((num_events * (double) rand ()) / (RAND_MAX + 1.0));
2085
2086 if (debug_threads && num_events > 1)
87ce2a04
DE
2087 debug_printf ("SEL: Found %d SIGTRAP events, selecting #%d\n",
2088 num_events, random_selector);
6bf5e0ba
PA
2089
2090 event_lp = (struct lwp_info *) find_inferior (&all_lwps,
2091 select_event_lwp_callback,
2092 &random_selector);
2093 }
2094
2095 if (event_lp != NULL)
2096 {
2097 /* Switch the event LWP. */
2098 *orig_lp = event_lp;
2099 }
2100}
2101
7984d532
PA
2102/* Decrement the suspend count of an LWP. */
2103
2104static int
2105unsuspend_one_lwp (struct inferior_list_entry *entry, void *except)
2106{
2107 struct lwp_info *lwp = (struct lwp_info *) entry;
2108
2109 /* Ignore EXCEPT. */
2110 if (lwp == except)
2111 return 0;
2112
2113 lwp->suspended--;
2114
2115 gdb_assert (lwp->suspended >= 0);
2116 return 0;
2117}
2118
2119/* Decrement the suspend count of all LWPs, except EXCEPT, if non
2120 NULL. */
2121
2122static void
2123unsuspend_all_lwps (struct lwp_info *except)
2124{
2125 find_inferior (&all_lwps, unsuspend_one_lwp, except);
2126}
2127
fa593d66
PA
2128static void move_out_of_jump_pad_callback (struct inferior_list_entry *entry);
2129static int stuck_in_jump_pad_callback (struct inferior_list_entry *entry,
2130 void *data);
2131static int lwp_running (struct inferior_list_entry *entry, void *data);
2132static ptid_t linux_wait_1 (ptid_t ptid,
2133 struct target_waitstatus *ourstatus,
2134 int target_options);
2135
2136/* Stabilize threads (move out of jump pads).
2137
2138 If a thread is midway collecting a fast tracepoint, we need to
2139 finish the collection and move it out of the jump pad before
2140 reporting the signal.
2141
2142 This avoids recursion while collecting (when a signal arrives
2143 midway, and the signal handler itself collects), which would trash
2144 the trace buffer. In case the user set a breakpoint in a signal
2145 handler, this avoids the backtrace showing the jump pad, etc..
2146 Most importantly, there are certain things we can't do safely if
2147 threads are stopped in a jump pad (or in its callee's). For
2148 example:
2149
2150 - starting a new trace run. A thread still collecting the
2151 previous run, could trash the trace buffer when resumed. The trace
2152 buffer control structures would have been reset but the thread had
2153 no way to tell. The thread could even midway memcpy'ing to the
2154 buffer, which would mean that when resumed, it would clobber the
2155 trace buffer that had been set for a new run.
2156
2157 - we can't rewrite/reuse the jump pads for new tracepoints
2158 safely. Say you do tstart while a thread is stopped midway while
2159 collecting. When the thread is later resumed, it finishes the
2160 collection, and returns to the jump pad, to execute the original
2161 instruction that was under the tracepoint jump at the time the
2162 older run had been started. If the jump pad had been rewritten
2163 since for something else in the new run, the thread would now
2164 execute the wrong / random instructions. */
2165
2166static void
2167linux_stabilize_threads (void)
2168{
2169 struct thread_info *save_inferior;
2170 struct lwp_info *lwp_stuck;
2171
2172 lwp_stuck
2173 = (struct lwp_info *) find_inferior (&all_lwps,
2174 stuck_in_jump_pad_callback, NULL);
2175 if (lwp_stuck != NULL)
2176 {
b4d51a55 2177 if (debug_threads)
87ce2a04
DE
2178 debug_printf ("can't stabilize, LWP %ld is stuck in jump pad\n",
2179 lwpid_of (lwp_stuck));
fa593d66
PA
2180 return;
2181 }
2182
2183 save_inferior = current_inferior;
2184
2185 stabilizing_threads = 1;
2186
2187 /* Kick 'em all. */
2188 for_each_inferior (&all_lwps, move_out_of_jump_pad_callback);
2189
2190 /* Loop until all are stopped out of the jump pads. */
2191 while (find_inferior (&all_lwps, lwp_running, NULL) != NULL)
2192 {
2193 struct target_waitstatus ourstatus;
2194 struct lwp_info *lwp;
fa593d66
PA
2195 int wstat;
2196
2197 /* Note that we go through the full wait even loop. While
2198 moving threads out of jump pad, we need to be able to step
2199 over internal breakpoints and such. */
32fcada3 2200 linux_wait_1 (minus_one_ptid, &ourstatus, 0);
fa593d66
PA
2201
2202 if (ourstatus.kind == TARGET_WAITKIND_STOPPED)
2203 {
2204 lwp = get_thread_lwp (current_inferior);
2205
2206 /* Lock it. */
2207 lwp->suspended++;
2208
a493e3e2 2209 if (ourstatus.value.sig != GDB_SIGNAL_0
fa593d66
PA
2210 || current_inferior->last_resume_kind == resume_stop)
2211 {
2ea28649 2212 wstat = W_STOPCODE (gdb_signal_to_host (ourstatus.value.sig));
fa593d66
PA
2213 enqueue_one_deferred_signal (lwp, &wstat);
2214 }
2215 }
2216 }
2217
2218 find_inferior (&all_lwps, unsuspend_one_lwp, NULL);
2219
2220 stabilizing_threads = 0;
2221
2222 current_inferior = save_inferior;
2223
b4d51a55 2224 if (debug_threads)
fa593d66 2225 {
b4d51a55
PA
2226 lwp_stuck
2227 = (struct lwp_info *) find_inferior (&all_lwps,
2228 stuck_in_jump_pad_callback, NULL);
2229 if (lwp_stuck != NULL)
87ce2a04
DE
2230 debug_printf ("couldn't stabilize, LWP %ld got stuck in jump pad\n",
2231 lwpid_of (lwp_stuck));
fa593d66
PA
2232 }
2233}
2234
0d62e5e8 2235/* Wait for process, returns status. */
da6d8c04 2236
95954743
PA
2237static ptid_t
2238linux_wait_1 (ptid_t ptid,
2239 struct target_waitstatus *ourstatus, int target_options)
da6d8c04 2240{
e5f1222d 2241 int w;
fc7238bb 2242 struct lwp_info *event_child;
bd99dc85 2243 int options;
bd99dc85 2244 int pid;
6bf5e0ba
PA
2245 int step_over_finished;
2246 int bp_explains_trap;
2247 int maybe_internal_trap;
2248 int report_to_gdb;
219f2f23 2249 int trace_event;
c2d6af84 2250 int in_step_range;
bd99dc85 2251
87ce2a04
DE
2252 if (debug_threads)
2253 {
2254 debug_enter ();
2255 debug_printf ("linux_wait_1: [%s]\n", target_pid_to_str (ptid));
2256 }
2257
bd99dc85
PA
2258 /* Translate generic target options into linux options. */
2259 options = __WALL;
2260 if (target_options & TARGET_WNOHANG)
2261 options |= WNOHANG;
0d62e5e8
DJ
2262
2263retry:
fa593d66
PA
2264 bp_explains_trap = 0;
2265 trace_event = 0;
c2d6af84 2266 in_step_range = 0;
bd99dc85
PA
2267 ourstatus->kind = TARGET_WAITKIND_IGNORE;
2268
0d62e5e8
DJ
2269 /* If we were only supposed to resume one thread, only wait for
2270 that thread - if it's still alive. If it died, however - which
2271 can happen if we're coming from the thread death case below -
2272 then we need to make sure we restart the other threads. We could
2273 pick a thread at random or restart all; restarting all is less
2274 arbitrary. */
95954743
PA
2275 if (!non_stop
2276 && !ptid_equal (cont_thread, null_ptid)
2277 && !ptid_equal (cont_thread, minus_one_ptid))
0d62e5e8 2278 {
fc7238bb
PA
2279 struct thread_info *thread;
2280
bd99dc85
PA
2281 thread = (struct thread_info *) find_inferior_id (&all_threads,
2282 cont_thread);
0d62e5e8
DJ
2283
2284 /* No stepping, no signal - unless one is pending already, of course. */
bd99dc85 2285 if (thread == NULL)
64386c31
DJ
2286 {
2287 struct thread_resume resume_info;
95954743 2288 resume_info.thread = minus_one_ptid;
bd99dc85
PA
2289 resume_info.kind = resume_continue;
2290 resume_info.sig = 0;
2bd7c093 2291 linux_resume (&resume_info, 1);
64386c31 2292 }
bd99dc85 2293 else
95954743 2294 ptid = cont_thread;
0d62e5e8 2295 }
da6d8c04 2296
6bf5e0ba
PA
2297 if (ptid_equal (step_over_bkpt, null_ptid))
2298 pid = linux_wait_for_event (ptid, &w, options);
2299 else
2300 {
2301 if (debug_threads)
87ce2a04
DE
2302 debug_printf ("step_over_bkpt set [%s], doing a blocking wait\n",
2303 target_pid_to_str (step_over_bkpt));
6bf5e0ba
PA
2304 pid = linux_wait_for_event (step_over_bkpt, &w, options & ~WNOHANG);
2305 }
2306
bd99dc85 2307 if (pid == 0) /* only if TARGET_WNOHANG */
87ce2a04
DE
2308 {
2309 if (debug_threads)
2310 {
2311 debug_printf ("linux_wait_1 ret = null_ptid\n");
2312 debug_exit ();
2313 }
2314 return null_ptid;
2315 }
bd99dc85 2316
6bf5e0ba 2317 event_child = get_thread_lwp (current_inferior);
da6d8c04 2318
0d62e5e8
DJ
2319 /* If we are waiting for a particular child, and it exited,
2320 linux_wait_for_event will return its exit status. Similarly if
2321 the last child exited. If this is not the last child, however,
2322 do not report it as exited until there is a 'thread exited' response
2323 available in the remote protocol. Instead, just wait for another event.
2324 This should be safe, because if the thread crashed we will already
2325 have reported the termination signal to GDB; that should stop any
2326 in-progress stepping operations, etc.
2327
2328 Report the exit status of the last thread to exit. This matches
2329 LinuxThreads' behavior. */
2330
95954743 2331 if (last_thread_of_process_p (current_inferior))
da6d8c04 2332 {
bd99dc85 2333 if (WIFEXITED (w) || WIFSIGNALED (w))
0d62e5e8 2334 {
bd99dc85
PA
2335 if (WIFEXITED (w))
2336 {
2337 ourstatus->kind = TARGET_WAITKIND_EXITED;
2338 ourstatus->value.integer = WEXITSTATUS (w);
2339
2340 if (debug_threads)
87ce2a04
DE
2341 {
2342 debug_printf ("linux_wait_1 ret = %s, exited with "
2343 "retcode %d\n",
2344 target_pid_to_str (ptid_of (event_child)),
2345 WEXITSTATUS (w));
2346 debug_exit ();
2347 }
bd99dc85
PA
2348 }
2349 else
2350 {
2351 ourstatus->kind = TARGET_WAITKIND_SIGNALLED;
2ea28649 2352 ourstatus->value.sig = gdb_signal_from_host (WTERMSIG (w));
bd99dc85
PA
2353
2354 if (debug_threads)
87ce2a04
DE
2355 {
2356 debug_printf ("linux_wait_1 ret = %s, terminated with "
2357 "signal %d\n",
2358 target_pid_to_str (ptid_of (event_child)),
2359 WTERMSIG (w));
2360 debug_exit ();
2361 }
bd99dc85 2362 }
5b1c542e 2363
3e4c1235 2364 return ptid_of (event_child);
0d62e5e8 2365 }
da6d8c04 2366 }
0d62e5e8 2367 else
da6d8c04 2368 {
0d62e5e8
DJ
2369 if (!WIFSTOPPED (w))
2370 goto retry;
da6d8c04
DJ
2371 }
2372
6bf5e0ba
PA
2373 /* If this event was not handled before, and is not a SIGTRAP, we
2374 report it. SIGILL and SIGSEGV are also treated as traps in case
2375 a breakpoint is inserted at the current PC. If this target does
2376 not support internal breakpoints at all, we also report the
2377 SIGTRAP without further processing; it's of no concern to us. */
2378 maybe_internal_trap
2379 = (supports_breakpoints ()
2380 && (WSTOPSIG (w) == SIGTRAP
2381 || ((WSTOPSIG (w) == SIGILL
2382 || WSTOPSIG (w) == SIGSEGV)
2383 && (*the_low_target.breakpoint_at) (event_child->stop_pc))));
2384
2385 if (maybe_internal_trap)
2386 {
2387 /* Handle anything that requires bookkeeping before deciding to
2388 report the event or continue waiting. */
2389
2390 /* First check if we can explain the SIGTRAP with an internal
2391 breakpoint, or if we should possibly report the event to GDB.
2392 Do this before anything that may remove or insert a
2393 breakpoint. */
2394 bp_explains_trap = breakpoint_inserted_here (event_child->stop_pc);
2395
2396 /* We have a SIGTRAP, possibly a step-over dance has just
2397 finished. If so, tweak the state machine accordingly,
2398 reinsert breakpoints and delete any reinsert (software
2399 single-step) breakpoints. */
2400 step_over_finished = finish_step_over (event_child);
2401
2402 /* Now invoke the callbacks of any internal breakpoints there. */
2403 check_breakpoints (event_child->stop_pc);
2404
219f2f23
PA
2405 /* Handle tracepoint data collecting. This may overflow the
2406 trace buffer, and cause a tracing stop, removing
2407 breakpoints. */
2408 trace_event = handle_tracepoints (event_child);
2409
6bf5e0ba
PA
2410 if (bp_explains_trap)
2411 {
2412 /* If we stepped or ran into an internal breakpoint, we've
2413 already handled it. So next time we resume (from this
2414 PC), we should step over it. */
2415 if (debug_threads)
87ce2a04 2416 debug_printf ("Hit a gdbserver breakpoint.\n");
6bf5e0ba 2417
8b07ae33
PA
2418 if (breakpoint_here (event_child->stop_pc))
2419 event_child->need_step_over = 1;
6bf5e0ba
PA
2420 }
2421 }
2422 else
2423 {
2424 /* We have some other signal, possibly a step-over dance was in
2425 progress, and it should be cancelled too. */
2426 step_over_finished = finish_step_over (event_child);
fa593d66
PA
2427 }
2428
2429 /* We have all the data we need. Either report the event to GDB, or
2430 resume threads and keep waiting for more. */
2431
2432 /* If we're collecting a fast tracepoint, finish the collection and
2433 move out of the jump pad before delivering a signal. See
2434 linux_stabilize_threads. */
2435
2436 if (WIFSTOPPED (w)
2437 && WSTOPSIG (w) != SIGTRAP
2438 && supports_fast_tracepoints ()
58b4daa5 2439 && agent_loaded_p ())
fa593d66
PA
2440 {
2441 if (debug_threads)
87ce2a04
DE
2442 debug_printf ("Got signal %d for LWP %ld. Check if we need "
2443 "to defer or adjust it.\n",
2444 WSTOPSIG (w), lwpid_of (event_child));
fa593d66
PA
2445
2446 /* Allow debugging the jump pad itself. */
2447 if (current_inferior->last_resume_kind != resume_step
2448 && maybe_move_out_of_jump_pad (event_child, &w))
2449 {
2450 enqueue_one_deferred_signal (event_child, &w);
2451
2452 if (debug_threads)
87ce2a04
DE
2453 debug_printf ("Signal %d for LWP %ld deferred (in jump pad)\n",
2454 WSTOPSIG (w), lwpid_of (event_child));
fa593d66
PA
2455
2456 linux_resume_one_lwp (event_child, 0, 0, NULL);
2457 goto retry;
2458 }
2459 }
219f2f23 2460
fa593d66
PA
2461 if (event_child->collecting_fast_tracepoint)
2462 {
2463 if (debug_threads)
87ce2a04
DE
2464 debug_printf ("LWP %ld was trying to move out of the jump pad (%d). "
2465 "Check if we're already there.\n",
2466 lwpid_of (event_child),
2467 event_child->collecting_fast_tracepoint);
fa593d66
PA
2468
2469 trace_event = 1;
2470
2471 event_child->collecting_fast_tracepoint
2472 = linux_fast_tracepoint_collecting (event_child, NULL);
2473
2474 if (event_child->collecting_fast_tracepoint != 1)
2475 {
2476 /* No longer need this breakpoint. */
2477 if (event_child->exit_jump_pad_bkpt != NULL)
2478 {
2479 if (debug_threads)
87ce2a04
DE
2480 debug_printf ("No longer need exit-jump-pad bkpt; removing it."
2481 "stopping all threads momentarily.\n");
fa593d66
PA
2482
2483 /* Other running threads could hit this breakpoint.
2484 We don't handle moribund locations like GDB does,
2485 instead we always pause all threads when removing
2486 breakpoints, so that any step-over or
2487 decr_pc_after_break adjustment is always taken
2488 care of while the breakpoint is still
2489 inserted. */
2490 stop_all_lwps (1, event_child);
2491 cancel_breakpoints ();
2492
2493 delete_breakpoint (event_child->exit_jump_pad_bkpt);
2494 event_child->exit_jump_pad_bkpt = NULL;
2495
2496 unstop_all_lwps (1, event_child);
2497
2498 gdb_assert (event_child->suspended >= 0);
2499 }
2500 }
2501
2502 if (event_child->collecting_fast_tracepoint == 0)
2503 {
2504 if (debug_threads)
87ce2a04
DE
2505 debug_printf ("fast tracepoint finished "
2506 "collecting successfully.\n");
fa593d66
PA
2507
2508 /* We may have a deferred signal to report. */
2509 if (dequeue_one_deferred_signal (event_child, &w))
2510 {
2511 if (debug_threads)
87ce2a04 2512 debug_printf ("dequeued one signal.\n");
fa593d66 2513 }
3c11dd79 2514 else
fa593d66 2515 {
3c11dd79 2516 if (debug_threads)
87ce2a04 2517 debug_printf ("no deferred signals.\n");
fa593d66
PA
2518
2519 if (stabilizing_threads)
2520 {
2521 ourstatus->kind = TARGET_WAITKIND_STOPPED;
a493e3e2 2522 ourstatus->value.sig = GDB_SIGNAL_0;
87ce2a04
DE
2523
2524 if (debug_threads)
2525 {
2526 debug_printf ("linux_wait_1 ret = %s, stopped "
2527 "while stabilizing threads\n",
2528 target_pid_to_str (ptid_of (event_child)));
2529 debug_exit ();
2530 }
2531
fa593d66
PA
2532 return ptid_of (event_child);
2533 }
2534 }
2535 }
6bf5e0ba
PA
2536 }
2537
e471f25b
PA
2538 /* Check whether GDB would be interested in this event. */
2539
2540 /* If GDB is not interested in this signal, don't stop other
2541 threads, and don't report it to GDB. Just resume the inferior
2542 right away. We do this for threading-related signals as well as
2543 any that GDB specifically requested we ignore. But never ignore
2544 SIGSTOP if we sent it ourselves, and do not ignore signals when
2545 stepping - they may require special handling to skip the signal
2546 handler. */
2547 /* FIXME drow/2002-06-09: Get signal numbers from the inferior's
2548 thread library? */
2549 if (WIFSTOPPED (w)
2550 && current_inferior->last_resume_kind != resume_step
2551 && (
1a981360 2552#if defined (USE_THREAD_DB) && !defined (__ANDROID__)
e471f25b
PA
2553 (current_process ()->private->thread_db != NULL
2554 && (WSTOPSIG (w) == __SIGRTMIN
2555 || WSTOPSIG (w) == __SIGRTMIN + 1))
2556 ||
2557#endif
2ea28649 2558 (pass_signals[gdb_signal_from_host (WSTOPSIG (w))]
e471f25b
PA
2559 && !(WSTOPSIG (w) == SIGSTOP
2560 && current_inferior->last_resume_kind == resume_stop))))
2561 {
2562 siginfo_t info, *info_p;
2563
2564 if (debug_threads)
87ce2a04
DE
2565 debug_printf ("Ignored signal %d for LWP %ld.\n",
2566 WSTOPSIG (w), lwpid_of (event_child));
e471f25b 2567
56f7af9c 2568 if (ptrace (PTRACE_GETSIGINFO, lwpid_of (event_child),
b8e1b30e 2569 (PTRACE_TYPE_ARG3) 0, &info) == 0)
e471f25b
PA
2570 info_p = &info;
2571 else
2572 info_p = NULL;
2573 linux_resume_one_lwp (event_child, event_child->stepping,
2574 WSTOPSIG (w), info_p);
2575 goto retry;
2576 }
2577
c2d6af84
PA
2578 /* Note that all addresses are always "out of the step range" when
2579 there's no range to begin with. */
2580 in_step_range = lwp_in_step_range (event_child);
2581
2582 /* If GDB wanted this thread to single step, and the thread is out
2583 of the step range, we always want to report the SIGTRAP, and let
2584 GDB handle it. Watchpoints should always be reported. So should
2585 signals we can't explain. A SIGTRAP we can't explain could be a
2586 GDB breakpoint --- we may or not support Z0 breakpoints. If we
2587 do, we're be able to handle GDB breakpoints on top of internal
2588 breakpoints, by handling the internal breakpoint and still
2589 reporting the event to GDB. If we don't, we're out of luck, GDB
2590 won't see the breakpoint hit. */
6bf5e0ba 2591 report_to_gdb = (!maybe_internal_trap
c2d6af84
PA
2592 || (current_inferior->last_resume_kind == resume_step
2593 && !in_step_range)
6bf5e0ba 2594 || event_child->stopped_by_watchpoint
c2d6af84 2595 || (!step_over_finished && !in_step_range
493e2a69 2596 && !bp_explains_trap && !trace_event)
9f3a5c85 2597 || (gdb_breakpoint_here (event_child->stop_pc)
d3ce09f5
SS
2598 && gdb_condition_true_at_breakpoint (event_child->stop_pc)
2599 && gdb_no_commands_at_breakpoint (event_child->stop_pc)));
2600
2601 run_breakpoint_commands (event_child->stop_pc);
6bf5e0ba
PA
2602
2603 /* We found no reason GDB would want us to stop. We either hit one
2604 of our own breakpoints, or finished an internal step GDB
2605 shouldn't know about. */
2606 if (!report_to_gdb)
2607 {
2608 if (debug_threads)
2609 {
2610 if (bp_explains_trap)
87ce2a04 2611 debug_printf ("Hit a gdbserver breakpoint.\n");
6bf5e0ba 2612 if (step_over_finished)
87ce2a04 2613 debug_printf ("Step-over finished.\n");
219f2f23 2614 if (trace_event)
87ce2a04 2615 debug_printf ("Tracepoint event.\n");
c2d6af84 2616 if (lwp_in_step_range (event_child))
87ce2a04
DE
2617 debug_printf ("Range stepping pc 0x%s [0x%s, 0x%s).\n",
2618 paddress (event_child->stop_pc),
2619 paddress (event_child->step_range_start),
2620 paddress (event_child->step_range_end));
6bf5e0ba
PA
2621 }
2622
2623 /* We're not reporting this breakpoint to GDB, so apply the
2624 decr_pc_after_break adjustment to the inferior's regcache
2625 ourselves. */
2626
2627 if (the_low_target.set_pc != NULL)
2628 {
2629 struct regcache *regcache
2630 = get_thread_regcache (get_lwp_thread (event_child), 1);
2631 (*the_low_target.set_pc) (regcache, event_child->stop_pc);
2632 }
2633
7984d532
PA
2634 /* We may have finished stepping over a breakpoint. If so,
2635 we've stopped and suspended all LWPs momentarily except the
2636 stepping one. This is where we resume them all again. We're
2637 going to keep waiting, so use proceed, which handles stepping
2638 over the next breakpoint. */
6bf5e0ba 2639 if (debug_threads)
87ce2a04 2640 debug_printf ("proceeding all threads.\n");
7984d532
PA
2641
2642 if (step_over_finished)
2643 unsuspend_all_lwps (event_child);
2644
6bf5e0ba
PA
2645 proceed_all_lwps ();
2646 goto retry;
2647 }
2648
2649 if (debug_threads)
2650 {
8336d594 2651 if (current_inferior->last_resume_kind == resume_step)
c2d6af84
PA
2652 {
2653 if (event_child->step_range_start == event_child->step_range_end)
87ce2a04 2654 debug_printf ("GDB wanted to single-step, reporting event.\n");
c2d6af84 2655 else if (!lwp_in_step_range (event_child))
87ce2a04 2656 debug_printf ("Out of step range, reporting event.\n");
c2d6af84 2657 }
6bf5e0ba 2658 if (event_child->stopped_by_watchpoint)
87ce2a04 2659 debug_printf ("Stopped by watchpoint.\n");
8b07ae33 2660 if (gdb_breakpoint_here (event_child->stop_pc))
87ce2a04 2661 debug_printf ("Stopped by GDB breakpoint.\n");
6bf5e0ba 2662 if (debug_threads)
87ce2a04 2663 debug_printf ("Hit a non-gdbserver trap event.\n");
6bf5e0ba
PA
2664 }
2665
2666 /* Alright, we're going to report a stop. */
2667
fa593d66 2668 if (!non_stop && !stabilizing_threads)
6bf5e0ba
PA
2669 {
2670 /* In all-stop, stop all threads. */
7984d532 2671 stop_all_lwps (0, NULL);
6bf5e0ba
PA
2672
2673 /* If we're not waiting for a specific LWP, choose an event LWP
2674 from among those that have had events. Giving equal priority
2675 to all LWPs that have had events helps prevent
2676 starvation. */
2677 if (ptid_equal (ptid, minus_one_ptid))
2678 {
2679 event_child->status_pending_p = 1;
2680 event_child->status_pending = w;
2681
2682 select_event_lwp (&event_child);
2683
ee1e2d4f
DE
2684 /* current_inferior and event_child must stay in sync. */
2685 current_inferior = get_lwp_thread (event_child);
2686
6bf5e0ba
PA
2687 event_child->status_pending_p = 0;
2688 w = event_child->status_pending;
2689 }
2690
2691 /* Now that we've selected our final event LWP, cancel any
2692 breakpoints in other LWPs that have hit a GDB breakpoint.
2693 See the comment in cancel_breakpoints_callback to find out
2694 why. */
2695 find_inferior (&all_lwps, cancel_breakpoints_callback, event_child);
fa593d66 2696
c03e6ccc
YQ
2697 /* If we were going a step-over, all other threads but the stepping one
2698 had been paused in start_step_over, with their suspend counts
2699 incremented. We don't want to do a full unstop/unpause, because we're
2700 in all-stop mode (so we want threads stopped), but we still need to
2701 unsuspend the other threads, to decrement their `suspended' count
2702 back. */
2703 if (step_over_finished)
2704 unsuspend_all_lwps (event_child);
2705
fa593d66
PA
2706 /* Stabilize threads (move out of jump pads). */
2707 stabilize_threads ();
6bf5e0ba
PA
2708 }
2709 else
2710 {
2711 /* If we just finished a step-over, then all threads had been
2712 momentarily paused. In all-stop, that's fine, we want
2713 threads stopped by now anyway. In non-stop, we need to
2714 re-resume threads that GDB wanted to be running. */
2715 if (step_over_finished)
7984d532 2716 unstop_all_lwps (1, event_child);
6bf5e0ba
PA
2717 }
2718
5b1c542e 2719 ourstatus->kind = TARGET_WAITKIND_STOPPED;
5b1c542e 2720
8336d594
PA
2721 if (current_inferior->last_resume_kind == resume_stop
2722 && WSTOPSIG (w) == SIGSTOP)
bd99dc85
PA
2723 {
2724 /* A thread that has been requested to stop by GDB with vCont;t,
2725 and it stopped cleanly, so report as SIG0. The use of
2726 SIGSTOP is an implementation detail. */
a493e3e2 2727 ourstatus->value.sig = GDB_SIGNAL_0;
bd99dc85 2728 }
8336d594
PA
2729 else if (current_inferior->last_resume_kind == resume_stop
2730 && WSTOPSIG (w) != SIGSTOP)
bd99dc85
PA
2731 {
2732 /* A thread that has been requested to stop by GDB with vCont;t,
d50171e4 2733 but, it stopped for other reasons. */
2ea28649 2734 ourstatus->value.sig = gdb_signal_from_host (WSTOPSIG (w));
bd99dc85
PA
2735 }
2736 else
2737 {
2ea28649 2738 ourstatus->value.sig = gdb_signal_from_host (WSTOPSIG (w));
bd99dc85
PA
2739 }
2740
d50171e4
PA
2741 gdb_assert (ptid_equal (step_over_bkpt, null_ptid));
2742
bd99dc85 2743 if (debug_threads)
87ce2a04
DE
2744 {
2745 debug_printf ("linux_wait_1 ret = %s, %d, %d\n",
2746 target_pid_to_str (ptid_of (event_child)),
2747 ourstatus->kind, ourstatus->value.sig);
2748 debug_exit ();
2749 }
bd99dc85 2750
6bf5e0ba 2751 return ptid_of (event_child);
bd99dc85
PA
2752}
2753
2754/* Get rid of any pending event in the pipe. */
2755static void
2756async_file_flush (void)
2757{
2758 int ret;
2759 char buf;
2760
2761 do
2762 ret = read (linux_event_pipe[0], &buf, 1);
2763 while (ret >= 0 || (ret == -1 && errno == EINTR));
2764}
2765
2766/* Put something in the pipe, so the event loop wakes up. */
2767static void
2768async_file_mark (void)
2769{
2770 int ret;
2771
2772 async_file_flush ();
2773
2774 do
2775 ret = write (linux_event_pipe[1], "+", 1);
2776 while (ret == 0 || (ret == -1 && errno == EINTR));
2777
2778 /* Ignore EAGAIN. If the pipe is full, the event loop will already
2779 be awakened anyway. */
2780}
2781
95954743
PA
2782static ptid_t
2783linux_wait (ptid_t ptid,
2784 struct target_waitstatus *ourstatus, int target_options)
bd99dc85 2785{
95954743 2786 ptid_t event_ptid;
bd99dc85 2787
bd99dc85
PA
2788 /* Flush the async file first. */
2789 if (target_is_async_p ())
2790 async_file_flush ();
2791
95954743 2792 event_ptid = linux_wait_1 (ptid, ourstatus, target_options);
bd99dc85
PA
2793
2794 /* If at least one stop was reported, there may be more. A single
2795 SIGCHLD can signal more than one child stop. */
2796 if (target_is_async_p ()
2797 && (target_options & TARGET_WNOHANG) != 0
95954743 2798 && !ptid_equal (event_ptid, null_ptid))
bd99dc85
PA
2799 async_file_mark ();
2800
2801 return event_ptid;
da6d8c04
DJ
2802}
2803
c5f62d5f 2804/* Send a signal to an LWP. */
fd500816
DJ
2805
2806static int
a1928bad 2807kill_lwp (unsigned long lwpid, int signo)
fd500816 2808{
c5f62d5f
DE
2809 /* Use tkill, if possible, in case we are using nptl threads. If tkill
2810 fails, then we are not using nptl threads and we should be using kill. */
fd500816 2811
c5f62d5f
DE
2812#ifdef __NR_tkill
2813 {
2814 static int tkill_failed;
fd500816 2815
c5f62d5f
DE
2816 if (!tkill_failed)
2817 {
2818 int ret;
2819
2820 errno = 0;
2821 ret = syscall (__NR_tkill, lwpid, signo);
2822 if (errno != ENOSYS)
2823 return ret;
2824 tkill_failed = 1;
2825 }
2826 }
fd500816
DJ
2827#endif
2828
2829 return kill (lwpid, signo);
2830}
2831
964e4306
PA
2832void
2833linux_stop_lwp (struct lwp_info *lwp)
2834{
2835 send_sigstop (lwp);
2836}
2837
0d62e5e8 2838static void
02fc4de7 2839send_sigstop (struct lwp_info *lwp)
0d62e5e8 2840{
bd99dc85 2841 int pid;
0d62e5e8 2842
bd99dc85
PA
2843 pid = lwpid_of (lwp);
2844
0d62e5e8
DJ
2845 /* If we already have a pending stop signal for this process, don't
2846 send another. */
54a0b537 2847 if (lwp->stop_expected)
0d62e5e8 2848 {
ae13219e 2849 if (debug_threads)
87ce2a04 2850 debug_printf ("Have pending sigstop for lwp %d\n", pid);
ae13219e 2851
0d62e5e8
DJ
2852 return;
2853 }
2854
2855 if (debug_threads)
87ce2a04 2856 debug_printf ("Sending sigstop to lwp %d\n", pid);
0d62e5e8 2857
d50171e4 2858 lwp->stop_expected = 1;
bd99dc85 2859 kill_lwp (pid, SIGSTOP);
0d62e5e8
DJ
2860}
2861
7984d532
PA
2862static int
2863send_sigstop_callback (struct inferior_list_entry *entry, void *except)
02fc4de7
PA
2864{
2865 struct lwp_info *lwp = (struct lwp_info *) entry;
2866
7984d532
PA
2867 /* Ignore EXCEPT. */
2868 if (lwp == except)
2869 return 0;
2870
02fc4de7 2871 if (lwp->stopped)
7984d532 2872 return 0;
02fc4de7
PA
2873
2874 send_sigstop (lwp);
7984d532
PA
2875 return 0;
2876}
2877
2878/* Increment the suspend count of an LWP, and stop it, if not stopped
2879 yet. */
2880static int
2881suspend_and_send_sigstop_callback (struct inferior_list_entry *entry,
2882 void *except)
2883{
2884 struct lwp_info *lwp = (struct lwp_info *) entry;
2885
2886 /* Ignore EXCEPT. */
2887 if (lwp == except)
2888 return 0;
2889
2890 lwp->suspended++;
2891
2892 return send_sigstop_callback (entry, except);
02fc4de7
PA
2893}
2894
95954743
PA
2895static void
2896mark_lwp_dead (struct lwp_info *lwp, int wstat)
2897{
2898 /* It's dead, really. */
2899 lwp->dead = 1;
2900
2901 /* Store the exit status for later. */
2902 lwp->status_pending_p = 1;
2903 lwp->status_pending = wstat;
2904
95954743
PA
2905 /* Prevent trying to stop it. */
2906 lwp->stopped = 1;
2907
2908 /* No further stops are expected from a dead lwp. */
2909 lwp->stop_expected = 0;
2910}
2911
0d62e5e8
DJ
2912static void
2913wait_for_sigstop (struct inferior_list_entry *entry)
2914{
54a0b537 2915 struct lwp_info *lwp = (struct lwp_info *) entry;
bd99dc85 2916 struct thread_info *saved_inferior;
a1928bad 2917 int wstat;
95954743
PA
2918 ptid_t saved_tid;
2919 ptid_t ptid;
d50171e4 2920 int pid;
0d62e5e8 2921
54a0b537 2922 if (lwp->stopped)
d50171e4
PA
2923 {
2924 if (debug_threads)
87ce2a04
DE
2925 debug_printf ("wait_for_sigstop: LWP %ld already stopped\n",
2926 lwpid_of (lwp));
d50171e4
PA
2927 return;
2928 }
0d62e5e8
DJ
2929
2930 saved_inferior = current_inferior;
bd99dc85 2931 if (saved_inferior != NULL)
80894984 2932 saved_tid = saved_inferior->entry.id;
bd99dc85 2933 else
95954743 2934 saved_tid = null_ptid; /* avoid bogus unused warning */
bd99dc85 2935
80894984 2936 ptid = lwp->entry.id;
bd99dc85 2937
d50171e4 2938 if (debug_threads)
87ce2a04 2939 debug_printf ("wait_for_sigstop: pulling one event\n");
d50171e4
PA
2940
2941 pid = linux_wait_for_event (ptid, &wstat, __WALL);
0d62e5e8
DJ
2942
2943 /* If we stopped with a non-SIGSTOP signal, save it for later
2944 and record the pending SIGSTOP. If the process exited, just
2945 return. */
d50171e4 2946 if (WIFSTOPPED (wstat))
0d62e5e8
DJ
2947 {
2948 if (debug_threads)
87ce2a04
DE
2949 debug_printf ("LWP %ld stopped with signal %d\n",
2950 lwpid_of (lwp), WSTOPSIG (wstat));
c35fafde 2951
d50171e4 2952 if (WSTOPSIG (wstat) != SIGSTOP)
c35fafde
PA
2953 {
2954 if (debug_threads)
87ce2a04
DE
2955 debug_printf ("LWP %ld stopped with non-sigstop status %06x\n",
2956 lwpid_of (lwp), wstat);
d50171e4 2957
c35fafde
PA
2958 lwp->status_pending_p = 1;
2959 lwp->status_pending = wstat;
2960 }
0d62e5e8 2961 }
d50171e4 2962 else
95954743
PA
2963 {
2964 if (debug_threads)
87ce2a04 2965 debug_printf ("Process %d exited while stopping LWPs\n", pid);
95954743 2966
d50171e4
PA
2967 lwp = find_lwp_pid (pid_to_ptid (pid));
2968 if (lwp)
2969 {
2970 /* Leave this status pending for the next time we're able to
2971 report it. In the mean time, we'll report this lwp as
2972 dead to GDB, so GDB doesn't try to read registers and
2973 memory from it. This can only happen if this was the
2974 last thread of the process; otherwise, PID is removed
2975 from the thread tables before linux_wait_for_event
2976 returns. */
2977 mark_lwp_dead (lwp, wstat);
2978 }
95954743 2979 }
0d62e5e8 2980
bd99dc85 2981 if (saved_inferior == NULL || linux_thread_alive (saved_tid))
0d62e5e8
DJ
2982 current_inferior = saved_inferior;
2983 else
2984 {
2985 if (debug_threads)
87ce2a04 2986 debug_printf ("Previously current thread died.\n");
0d62e5e8 2987
bd99dc85
PA
2988 if (non_stop)
2989 {
2990 /* We can't change the current inferior behind GDB's back,
2991 otherwise, a subsequent command may apply to the wrong
2992 process. */
2993 current_inferior = NULL;
2994 }
2995 else
2996 {
2997 /* Set a valid thread as current. */
2998 set_desired_inferior (0);
2999 }
0d62e5e8
DJ
3000 }
3001}
3002
fa593d66
PA
3003/* Returns true if LWP ENTRY is stopped in a jump pad, and we can't
3004 move it out, because we need to report the stop event to GDB. For
3005 example, if the user puts a breakpoint in the jump pad, it's
3006 because she wants to debug it. */
3007
3008static int
3009stuck_in_jump_pad_callback (struct inferior_list_entry *entry, void *data)
3010{
3011 struct lwp_info *lwp = (struct lwp_info *) entry;
3012 struct thread_info *thread = get_lwp_thread (lwp);
3013
3014 gdb_assert (lwp->suspended == 0);
3015 gdb_assert (lwp->stopped);
3016
3017 /* Allow debugging the jump pad, gdb_collect, etc.. */
3018 return (supports_fast_tracepoints ()
58b4daa5 3019 && agent_loaded_p ()
fa593d66
PA
3020 && (gdb_breakpoint_here (lwp->stop_pc)
3021 || lwp->stopped_by_watchpoint
3022 || thread->last_resume_kind == resume_step)
3023 && linux_fast_tracepoint_collecting (lwp, NULL));
3024}
3025
3026static void
3027move_out_of_jump_pad_callback (struct inferior_list_entry *entry)
3028{
3029 struct lwp_info *lwp = (struct lwp_info *) entry;
3030 struct thread_info *thread = get_lwp_thread (lwp);
3031 int *wstat;
3032
3033 gdb_assert (lwp->suspended == 0);
3034 gdb_assert (lwp->stopped);
3035
3036 wstat = lwp->status_pending_p ? &lwp->status_pending : NULL;
3037
3038 /* Allow debugging the jump pad, gdb_collect, etc. */
3039 if (!gdb_breakpoint_here (lwp->stop_pc)
3040 && !lwp->stopped_by_watchpoint
3041 && thread->last_resume_kind != resume_step
3042 && maybe_move_out_of_jump_pad (lwp, wstat))
3043 {
3044 if (debug_threads)
87ce2a04
DE
3045 debug_printf ("LWP %ld needs stabilizing (in jump pad)\n",
3046 lwpid_of (lwp));
fa593d66
PA
3047
3048 if (wstat)
3049 {
3050 lwp->status_pending_p = 0;
3051 enqueue_one_deferred_signal (lwp, wstat);
3052
3053 if (debug_threads)
87ce2a04
DE
3054 debug_printf ("Signal %d for LWP %ld deferred "
3055 "(in jump pad)\n",
3056 WSTOPSIG (*wstat), lwpid_of (lwp));
fa593d66
PA
3057 }
3058
3059 linux_resume_one_lwp (lwp, 0, 0, NULL);
3060 }
3061 else
3062 lwp->suspended++;
3063}
3064
3065static int
3066lwp_running (struct inferior_list_entry *entry, void *data)
3067{
3068 struct lwp_info *lwp = (struct lwp_info *) entry;
3069
3070 if (lwp->dead)
3071 return 0;
3072 if (lwp->stopped)
3073 return 0;
3074 return 1;
3075}
3076
7984d532
PA
3077/* Stop all lwps that aren't stopped yet, except EXCEPT, if not NULL.
3078 If SUSPEND, then also increase the suspend count of every LWP,
3079 except EXCEPT. */
3080
0d62e5e8 3081static void
7984d532 3082stop_all_lwps (int suspend, struct lwp_info *except)
0d62e5e8 3083{
bde24c0a
PA
3084 /* Should not be called recursively. */
3085 gdb_assert (stopping_threads == NOT_STOPPING_THREADS);
3086
87ce2a04
DE
3087 if (debug_threads)
3088 {
3089 debug_enter ();
3090 debug_printf ("stop_all_lwps (%s, except=%s)\n",
3091 suspend ? "stop-and-suspend" : "stop",
3092 except != NULL
3093 ? target_pid_to_str (ptid_of (except))
3094 : "none");
3095 }
3096
bde24c0a
PA
3097 stopping_threads = (suspend
3098 ? STOPPING_AND_SUSPENDING_THREADS
3099 : STOPPING_THREADS);
7984d532
PA
3100
3101 if (suspend)
3102 find_inferior (&all_lwps, suspend_and_send_sigstop_callback, except);
3103 else
3104 find_inferior (&all_lwps, send_sigstop_callback, except);
54a0b537 3105 for_each_inferior (&all_lwps, wait_for_sigstop);
bde24c0a 3106 stopping_threads = NOT_STOPPING_THREADS;
87ce2a04
DE
3107
3108 if (debug_threads)
3109 {
3110 debug_printf ("stop_all_lwps done, setting stopping_threads "
3111 "back to !stopping\n");
3112 debug_exit ();
3113 }
0d62e5e8
DJ
3114}
3115
da6d8c04
DJ
3116/* Resume execution of the inferior process.
3117 If STEP is nonzero, single-step it.
3118 If SIGNAL is nonzero, give it that signal. */
3119
ce3a066d 3120static void
2acc282a 3121linux_resume_one_lwp (struct lwp_info *lwp,
54a0b537 3122 int step, int signal, siginfo_t *info)
da6d8c04 3123{
0d62e5e8 3124 struct thread_info *saved_inferior;
fa593d66 3125 int fast_tp_collecting;
0d62e5e8 3126
54a0b537 3127 if (lwp->stopped == 0)
0d62e5e8
DJ
3128 return;
3129
fa593d66
PA
3130 fast_tp_collecting = lwp->collecting_fast_tracepoint;
3131
3132 gdb_assert (!stabilizing_threads || fast_tp_collecting);
3133
219f2f23
PA
3134 /* Cancel actions that rely on GDB not changing the PC (e.g., the
3135 user used the "jump" command, or "set $pc = foo"). */
3136 if (lwp->stop_pc != get_pc (lwp))
3137 {
3138 /* Collecting 'while-stepping' actions doesn't make sense
3139 anymore. */
3140 release_while_stepping_state_list (get_lwp_thread (lwp));
3141 }
3142
0d62e5e8
DJ
3143 /* If we have pending signals or status, and a new signal, enqueue the
3144 signal. Also enqueue the signal if we are waiting to reinsert a
3145 breakpoint; it will be picked up again below. */
3146 if (signal != 0
fa593d66
PA
3147 && (lwp->status_pending_p
3148 || lwp->pending_signals != NULL
3149 || lwp->bp_reinsert != 0
3150 || fast_tp_collecting))
0d62e5e8
DJ
3151 {
3152 struct pending_signals *p_sig;
bca929d3 3153 p_sig = xmalloc (sizeof (*p_sig));
54a0b537 3154 p_sig->prev = lwp->pending_signals;
0d62e5e8 3155 p_sig->signal = signal;
32ca6d61
DJ
3156 if (info == NULL)
3157 memset (&p_sig->info, 0, sizeof (siginfo_t));
3158 else
3159 memcpy (&p_sig->info, info, sizeof (siginfo_t));
54a0b537 3160 lwp->pending_signals = p_sig;
0d62e5e8
DJ
3161 }
3162
d50171e4
PA
3163 if (lwp->status_pending_p)
3164 {
3165 if (debug_threads)
87ce2a04
DE
3166 debug_printf ("Not resuming lwp %ld (%s, signal %d, stop %s);"
3167 " has pending status\n",
3168 lwpid_of (lwp), step ? "step" : "continue", signal,
3169 lwp->stop_expected ? "expected" : "not expected");
d50171e4
PA
3170 return;
3171 }
0d62e5e8
DJ
3172
3173 saved_inferior = current_inferior;
54a0b537 3174 current_inferior = get_lwp_thread (lwp);
0d62e5e8
DJ
3175
3176 if (debug_threads)
87ce2a04
DE
3177 debug_printf ("Resuming lwp %ld (%s, signal %d, stop %s)\n",
3178 lwpid_of (lwp), step ? "step" : "continue", signal,
3179 lwp->stop_expected ? "expected" : "not expected");
0d62e5e8
DJ
3180
3181 /* This bit needs some thinking about. If we get a signal that
3182 we must report while a single-step reinsert is still pending,
3183 we often end up resuming the thread. It might be better to
3184 (ew) allow a stack of pending events; then we could be sure that
3185 the reinsert happened right away and not lose any signals.
3186
3187 Making this stack would also shrink the window in which breakpoints are
54a0b537 3188 uninserted (see comment in linux_wait_for_lwp) but not enough for
0d62e5e8
DJ
3189 complete correctness, so it won't solve that problem. It may be
3190 worthwhile just to solve this one, however. */
54a0b537 3191 if (lwp->bp_reinsert != 0)
0d62e5e8
DJ
3192 {
3193 if (debug_threads)
87ce2a04
DE
3194 debug_printf (" pending reinsert at 0x%s\n",
3195 paddress (lwp->bp_reinsert));
d50171e4 3196
85e00e85 3197 if (can_hardware_single_step ())
d50171e4 3198 {
fa593d66
PA
3199 if (fast_tp_collecting == 0)
3200 {
3201 if (step == 0)
3202 fprintf (stderr, "BAD - reinserting but not stepping.\n");
3203 if (lwp->suspended)
3204 fprintf (stderr, "BAD - reinserting and suspended(%d).\n",
3205 lwp->suspended);
3206 }
d50171e4
PA
3207
3208 step = 1;
3209 }
0d62e5e8
DJ
3210
3211 /* Postpone any pending signal. It was enqueued above. */
3212 signal = 0;
3213 }
3214
fa593d66
PA
3215 if (fast_tp_collecting == 1)
3216 {
3217 if (debug_threads)
87ce2a04
DE
3218 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
3219 " (exit-jump-pad-bkpt)\n",
3220 lwpid_of (lwp));
fa593d66
PA
3221
3222 /* Postpone any pending signal. It was enqueued above. */
3223 signal = 0;
3224 }
3225 else if (fast_tp_collecting == 2)
3226 {
3227 if (debug_threads)
87ce2a04
DE
3228 debug_printf ("lwp %ld wants to get out of fast tracepoint jump pad"
3229 " single-stepping\n",
3230 lwpid_of (lwp));
fa593d66
PA
3231
3232 if (can_hardware_single_step ())
3233 step = 1;
3234 else
3235 fatal ("moving out of jump pad single-stepping"
3236 " not implemented on this target");
3237
3238 /* Postpone any pending signal. It was enqueued above. */
3239 signal = 0;
3240 }
3241
219f2f23
PA
3242 /* If we have while-stepping actions in this thread set it stepping.
3243 If we have a signal to deliver, it may or may not be set to
3244 SIG_IGN, we don't know. Assume so, and allow collecting
3245 while-stepping into a signal handler. A possible smart thing to
3246 do would be to set an internal breakpoint at the signal return
3247 address, continue, and carry on catching this while-stepping
3248 action only when that breakpoint is hit. A future
3249 enhancement. */
3250 if (get_lwp_thread (lwp)->while_stepping != NULL
3251 && can_hardware_single_step ())
3252 {
3253 if (debug_threads)
87ce2a04
DE
3254 debug_printf ("lwp %ld has a while-stepping action -> forcing step.\n",
3255 lwpid_of (lwp));
219f2f23
PA
3256 step = 1;
3257 }
3258
aa691b87 3259 if (debug_threads && the_low_target.get_pc != NULL)
0d62e5e8 3260 {
442ea881
PA
3261 struct regcache *regcache = get_thread_regcache (current_inferior, 1);
3262 CORE_ADDR pc = (*the_low_target.get_pc) (regcache);
87ce2a04 3263 debug_printf (" resuming from pc 0x%lx\n", (long) pc);
0d62e5e8
DJ
3264 }
3265
fa593d66
PA
3266 /* If we have pending signals, consume one unless we are trying to
3267 reinsert a breakpoint or we're trying to finish a fast tracepoint
3268 collect. */
3269 if (lwp->pending_signals != NULL
3270 && lwp->bp_reinsert == 0
3271 && fast_tp_collecting == 0)
0d62e5e8
DJ
3272 {
3273 struct pending_signals **p_sig;
3274
54a0b537 3275 p_sig = &lwp->pending_signals;
0d62e5e8
DJ
3276 while ((*p_sig)->prev != NULL)
3277 p_sig = &(*p_sig)->prev;
3278
3279 signal = (*p_sig)->signal;
32ca6d61 3280 if ((*p_sig)->info.si_signo != 0)
b8e1b30e 3281 ptrace (PTRACE_SETSIGINFO, lwpid_of (lwp), (PTRACE_TYPE_ARG3) 0,
56f7af9c 3282 &(*p_sig)->info);
32ca6d61 3283
0d62e5e8
DJ
3284 free (*p_sig);
3285 *p_sig = NULL;
3286 }
3287
aa5ca48f
DE
3288 if (the_low_target.prepare_to_resume != NULL)
3289 the_low_target.prepare_to_resume (lwp);
3290
3aee8918 3291 regcache_invalidate_thread (get_lwp_thread (lwp));
da6d8c04 3292 errno = 0;
54a0b537 3293 lwp->stopped = 0;
c3adc08c 3294 lwp->stopped_by_watchpoint = 0;
54a0b537 3295 lwp->stepping = step;
56f7af9c 3296 ptrace (step ? PTRACE_SINGLESTEP : PTRACE_CONT, lwpid_of (lwp),
b8e1b30e 3297 (PTRACE_TYPE_ARG3) 0,
14ce3065
DE
3298 /* Coerce to a uintptr_t first to avoid potential gcc warning
3299 of coercing an 8 byte integer to a 4 byte pointer. */
b8e1b30e 3300 (PTRACE_TYPE_ARG4) (uintptr_t) signal);
0d62e5e8
DJ
3301
3302 current_inferior = saved_inferior;
da6d8c04 3303 if (errno)
3221518c
UW
3304 {
3305 /* ESRCH from ptrace either means that the thread was already
3306 running (an error) or that it is gone (a race condition). If
3307 it's gone, we will get a notification the next time we wait,
3308 so we can ignore the error. We could differentiate these
3309 two, but it's tricky without waiting; the thread still exists
3310 as a zombie, so sending it signal 0 would succeed. So just
3311 ignore ESRCH. */
3312 if (errno == ESRCH)
3313 return;
3314
3315 perror_with_name ("ptrace");
3316 }
da6d8c04
DJ
3317}
3318
2bd7c093
PA
3319struct thread_resume_array
3320{
3321 struct thread_resume *resume;
3322 size_t n;
3323};
64386c31 3324
ebcf782c
DE
3325/* This function is called once per thread via find_inferior.
3326 ARG is a pointer to a thread_resume_array struct.
3327 We look up the thread specified by ENTRY in ARG, and mark the thread
3328 with a pointer to the appropriate resume request.
5544ad89
DJ
3329
3330 This algorithm is O(threads * resume elements), but resume elements
3331 is small (and will remain small at least until GDB supports thread
3332 suspension). */
ebcf782c 3333
2bd7c093
PA
3334static int
3335linux_set_resume_request (struct inferior_list_entry *entry, void *arg)
0d62e5e8 3336{
54a0b537 3337 struct lwp_info *lwp;
64386c31 3338 struct thread_info *thread;
5544ad89 3339 int ndx;
2bd7c093 3340 struct thread_resume_array *r;
64386c31
DJ
3341
3342 thread = (struct thread_info *) entry;
54a0b537 3343 lwp = get_thread_lwp (thread);
2bd7c093 3344 r = arg;
64386c31 3345
2bd7c093 3346 for (ndx = 0; ndx < r->n; ndx++)
95954743
PA
3347 {
3348 ptid_t ptid = r->resume[ndx].thread;
3349 if (ptid_equal (ptid, minus_one_ptid)
3350 || ptid_equal (ptid, entry->id)
0c9070b3
YQ
3351 /* Handle both 'pPID' and 'pPID.-1' as meaning 'all threads
3352 of PID'. */
3353 || (ptid_get_pid (ptid) == pid_of (lwp)
3354 && (ptid_is_pid (ptid)
3355 || ptid_get_lwp (ptid) == -1)))
95954743 3356 {
d50171e4 3357 if (r->resume[ndx].kind == resume_stop
8336d594 3358 && thread->last_resume_kind == resume_stop)
d50171e4
PA
3359 {
3360 if (debug_threads)
87ce2a04
DE
3361 debug_printf ("already %s LWP %ld at GDB's request\n",
3362 (thread->last_status.kind
3363 == TARGET_WAITKIND_STOPPED)
3364 ? "stopped"
3365 : "stopping",
3366 lwpid_of (lwp));
d50171e4
PA
3367
3368 continue;
3369 }
3370
95954743 3371 lwp->resume = &r->resume[ndx];
8336d594 3372 thread->last_resume_kind = lwp->resume->kind;
fa593d66 3373
c2d6af84
PA
3374 lwp->step_range_start = lwp->resume->step_range_start;
3375 lwp->step_range_end = lwp->resume->step_range_end;
3376
fa593d66
PA
3377 /* If we had a deferred signal to report, dequeue one now.
3378 This can happen if LWP gets more than one signal while
3379 trying to get out of a jump pad. */
3380 if (lwp->stopped
3381 && !lwp->status_pending_p
3382 && dequeue_one_deferred_signal (lwp, &lwp->status_pending))
3383 {
3384 lwp->status_pending_p = 1;
3385
3386 if (debug_threads)
87ce2a04
DE
3387 debug_printf ("Dequeueing deferred signal %d for LWP %ld, "
3388 "leaving status pending.\n",
3389 WSTOPSIG (lwp->status_pending), lwpid_of (lwp));
fa593d66
PA
3390 }
3391
95954743
PA
3392 return 0;
3393 }
3394 }
2bd7c093
PA
3395
3396 /* No resume action for this thread. */
3397 lwp->resume = NULL;
64386c31 3398
2bd7c093 3399 return 0;
5544ad89
DJ
3400}
3401
20ad9378
DE
3402/* find_inferior callback for linux_resume.
3403 Set *FLAG_P if this lwp has an interesting status pending. */
5544ad89 3404
bd99dc85
PA
3405static int
3406resume_status_pending_p (struct inferior_list_entry *entry, void *flag_p)
5544ad89 3407{
bd99dc85 3408 struct lwp_info *lwp = (struct lwp_info *) entry;
5544ad89 3409
bd99dc85
PA
3410 /* LWPs which will not be resumed are not interesting, because
3411 we might not wait for them next time through linux_wait. */
2bd7c093 3412 if (lwp->resume == NULL)
bd99dc85 3413 return 0;
64386c31 3414
bd99dc85 3415 if (lwp->status_pending_p)
d50171e4
PA
3416 * (int *) flag_p = 1;
3417
3418 return 0;
3419}
3420
3421/* Return 1 if this lwp that GDB wants running is stopped at an
3422 internal breakpoint that we need to step over. It assumes that any
3423 required STOP_PC adjustment has already been propagated to the
3424 inferior's regcache. */
3425
3426static int
3427need_step_over_p (struct inferior_list_entry *entry, void *dummy)
3428{
3429 struct lwp_info *lwp = (struct lwp_info *) entry;
8336d594 3430 struct thread_info *thread;
d50171e4
PA
3431 struct thread_info *saved_inferior;
3432 CORE_ADDR pc;
3433
3434 /* LWPs which will not be resumed are not interesting, because we
3435 might not wait for them next time through linux_wait. */
3436
3437 if (!lwp->stopped)
3438 {
3439 if (debug_threads)
87ce2a04
DE
3440 debug_printf ("Need step over [LWP %ld]? Ignoring, not stopped\n",
3441 lwpid_of (lwp));
d50171e4
PA
3442 return 0;
3443 }
3444
8336d594
PA
3445 thread = get_lwp_thread (lwp);
3446
3447 if (thread->last_resume_kind == resume_stop)
d50171e4
PA
3448 {
3449 if (debug_threads)
87ce2a04
DE
3450 debug_printf ("Need step over [LWP %ld]? Ignoring, should remain"
3451 " stopped\n",
3452 lwpid_of (lwp));
d50171e4
PA
3453 return 0;
3454 }
3455
7984d532
PA
3456 gdb_assert (lwp->suspended >= 0);
3457
3458 if (lwp->suspended)
3459 {
3460 if (debug_threads)
87ce2a04
DE
3461 debug_printf ("Need step over [LWP %ld]? Ignoring, suspended\n",
3462 lwpid_of (lwp));
7984d532
PA
3463 return 0;
3464 }
3465
d50171e4
PA
3466 if (!lwp->need_step_over)
3467 {
3468 if (debug_threads)
87ce2a04 3469 debug_printf ("Need step over [LWP %ld]? No\n", lwpid_of (lwp));
d50171e4 3470 }
5544ad89 3471
bd99dc85 3472 if (lwp->status_pending_p)
d50171e4
PA
3473 {
3474 if (debug_threads)
87ce2a04
DE
3475 debug_printf ("Need step over [LWP %ld]? Ignoring, has pending"
3476 " status.\n",
3477 lwpid_of (lwp));
d50171e4
PA
3478 return 0;
3479 }
3480
3481 /* Note: PC, not STOP_PC. Either GDB has adjusted the PC already,
3482 or we have. */
3483 pc = get_pc (lwp);
3484
3485 /* If the PC has changed since we stopped, then don't do anything,
3486 and let the breakpoint/tracepoint be hit. This happens if, for
3487 instance, GDB handled the decr_pc_after_break subtraction itself,
3488 GDB is OOL stepping this thread, or the user has issued a "jump"
3489 command, or poked thread's registers herself. */
3490 if (pc != lwp->stop_pc)
3491 {
3492 if (debug_threads)
87ce2a04
DE
3493 debug_printf ("Need step over [LWP %ld]? Cancelling, PC was changed. "
3494 "Old stop_pc was 0x%s, PC is now 0x%s\n",
3495 lwpid_of (lwp), paddress (lwp->stop_pc), paddress (pc));
d50171e4
PA
3496
3497 lwp->need_step_over = 0;
3498 return 0;
3499 }
3500
3501 saved_inferior = current_inferior;
8336d594 3502 current_inferior = thread;
d50171e4 3503
8b07ae33 3504 /* We can only step over breakpoints we know about. */
fa593d66 3505 if (breakpoint_here (pc) || fast_tracepoint_jump_here (pc))
d50171e4 3506 {
8b07ae33 3507 /* Don't step over a breakpoint that GDB expects to hit
9f3a5c85
LM
3508 though. If the condition is being evaluated on the target's side
3509 and it evaluate to false, step over this breakpoint as well. */
3510 if (gdb_breakpoint_here (pc)
d3ce09f5
SS
3511 && gdb_condition_true_at_breakpoint (pc)
3512 && gdb_no_commands_at_breakpoint (pc))
8b07ae33
PA
3513 {
3514 if (debug_threads)
87ce2a04
DE
3515 debug_printf ("Need step over [LWP %ld]? yes, but found"
3516 " GDB breakpoint at 0x%s; skipping step over\n",
3517 lwpid_of (lwp), paddress (pc));
d50171e4 3518
8b07ae33
PA
3519 current_inferior = saved_inferior;
3520 return 0;
3521 }
3522 else
3523 {
3524 if (debug_threads)
87ce2a04
DE
3525 debug_printf ("Need step over [LWP %ld]? yes, "
3526 "found breakpoint at 0x%s\n",
3527 lwpid_of (lwp), paddress (pc));
d50171e4 3528
8b07ae33
PA
3529 /* We've found an lwp that needs stepping over --- return 1 so
3530 that find_inferior stops looking. */
3531 current_inferior = saved_inferior;
3532
3533 /* If the step over is cancelled, this is set again. */
3534 lwp->need_step_over = 0;
3535 return 1;
3536 }
d50171e4
PA
3537 }
3538
3539 current_inferior = saved_inferior;
3540
3541 if (debug_threads)
87ce2a04
DE
3542 debug_printf ("Need step over [LWP %ld]? No, no breakpoint found"
3543 " at 0x%s\n",
3544 lwpid_of (lwp), paddress (pc));
c6ecbae5 3545
bd99dc85 3546 return 0;
5544ad89
DJ
3547}
3548
d50171e4
PA
3549/* Start a step-over operation on LWP. When LWP stopped at a
3550 breakpoint, to make progress, we need to remove the breakpoint out
3551 of the way. If we let other threads run while we do that, they may
3552 pass by the breakpoint location and miss hitting it. To avoid
3553 that, a step-over momentarily stops all threads while LWP is
3554 single-stepped while the breakpoint is temporarily uninserted from
3555 the inferior. When the single-step finishes, we reinsert the
3556 breakpoint, and let all threads that are supposed to be running,
3557 run again.
3558
3559 On targets that don't support hardware single-step, we don't
3560 currently support full software single-stepping. Instead, we only
3561 support stepping over the thread event breakpoint, by asking the
3562 low target where to place a reinsert breakpoint. Since this
3563 routine assumes the breakpoint being stepped over is a thread event
3564 breakpoint, it usually assumes the return address of the current
3565 function is a good enough place to set the reinsert breakpoint. */
3566
3567static int
3568start_step_over (struct lwp_info *lwp)
3569{
3570 struct thread_info *saved_inferior;
3571 CORE_ADDR pc;
3572 int step;
3573
3574 if (debug_threads)
87ce2a04
DE
3575 debug_printf ("Starting step-over on LWP %ld. Stopping all threads\n",
3576 lwpid_of (lwp));
d50171e4 3577
7984d532
PA
3578 stop_all_lwps (1, lwp);
3579 gdb_assert (lwp->suspended == 0);
d50171e4
PA
3580
3581 if (debug_threads)
87ce2a04 3582 debug_printf ("Done stopping all threads for step-over.\n");
d50171e4
PA
3583
3584 /* Note, we should always reach here with an already adjusted PC,
3585 either by GDB (if we're resuming due to GDB's request), or by our
3586 caller, if we just finished handling an internal breakpoint GDB
3587 shouldn't care about. */
3588 pc = get_pc (lwp);
3589
3590 saved_inferior = current_inferior;
3591 current_inferior = get_lwp_thread (lwp);
3592
3593 lwp->bp_reinsert = pc;
3594 uninsert_breakpoints_at (pc);
fa593d66 3595 uninsert_fast_tracepoint_jumps_at (pc);
d50171e4
PA
3596
3597 if (can_hardware_single_step ())
3598 {
3599 step = 1;
3600 }
3601 else
3602 {
3603 CORE_ADDR raddr = (*the_low_target.breakpoint_reinsert_addr) ();
3604 set_reinsert_breakpoint (raddr);
3605 step = 0;
3606 }
3607
3608 current_inferior = saved_inferior;
3609
3610 linux_resume_one_lwp (lwp, step, 0, NULL);
3611
3612 /* Require next event from this LWP. */
80894984 3613 step_over_bkpt = lwp->entry.id;
d50171e4
PA
3614 return 1;
3615}
3616
3617/* Finish a step-over. Reinsert the breakpoint we had uninserted in
3618 start_step_over, if still there, and delete any reinsert
3619 breakpoints we've set, on non hardware single-step targets. */
3620
3621static int
3622finish_step_over (struct lwp_info *lwp)
3623{
3624 if (lwp->bp_reinsert != 0)
3625 {
3626 if (debug_threads)
87ce2a04 3627 debug_printf ("Finished step over.\n");
d50171e4
PA
3628
3629 /* Reinsert any breakpoint at LWP->BP_REINSERT. Note that there
3630 may be no breakpoint to reinsert there by now. */
3631 reinsert_breakpoints_at (lwp->bp_reinsert);
fa593d66 3632 reinsert_fast_tracepoint_jumps_at (lwp->bp_reinsert);
d50171e4
PA
3633
3634 lwp->bp_reinsert = 0;
3635
3636 /* Delete any software-single-step reinsert breakpoints. No
3637 longer needed. We don't have to worry about other threads
3638 hitting this trap, and later not being able to explain it,
3639 because we were stepping over a breakpoint, and we hold all
3640 threads but LWP stopped while doing that. */
3641 if (!can_hardware_single_step ())
3642 delete_reinsert_breakpoints ();
3643
3644 step_over_bkpt = null_ptid;
3645 return 1;
3646 }
3647 else
3648 return 0;
3649}
3650
5544ad89
DJ
3651/* This function is called once per thread. We check the thread's resume
3652 request, which will tell us whether to resume, step, or leave the thread
bd99dc85 3653 stopped; and what signal, if any, it should be sent.
5544ad89 3654
bd99dc85
PA
3655 For threads which we aren't explicitly told otherwise, we preserve
3656 the stepping flag; this is used for stepping over gdbserver-placed
3657 breakpoints.
3658
3659 If pending_flags was set in any thread, we queue any needed
3660 signals, since we won't actually resume. We already have a pending
3661 event to report, so we don't need to preserve any step requests;
3662 they should be re-issued if necessary. */
3663
3664static int
3665linux_resume_one_thread (struct inferior_list_entry *entry, void *arg)
5544ad89 3666{
54a0b537 3667 struct lwp_info *lwp;
5544ad89 3668 struct thread_info *thread;
bd99dc85 3669 int step;
d50171e4
PA
3670 int leave_all_stopped = * (int *) arg;
3671 int leave_pending;
5544ad89
DJ
3672
3673 thread = (struct thread_info *) entry;
54a0b537 3674 lwp = get_thread_lwp (thread);
5544ad89 3675
2bd7c093 3676 if (lwp->resume == NULL)
bd99dc85 3677 return 0;
5544ad89 3678
bd99dc85 3679 if (lwp->resume->kind == resume_stop)
5544ad89 3680 {
bd99dc85 3681 if (debug_threads)
87ce2a04 3682 debug_printf ("resume_stop request for LWP %ld\n", lwpid_of (lwp));
bd99dc85
PA
3683
3684 if (!lwp->stopped)
3685 {
3686 if (debug_threads)
87ce2a04 3687 debug_printf ("stopping LWP %ld\n", lwpid_of (lwp));
bd99dc85 3688
d50171e4
PA
3689 /* Stop the thread, and wait for the event asynchronously,
3690 through the event loop. */
02fc4de7 3691 send_sigstop (lwp);
bd99dc85
PA
3692 }
3693 else
3694 {
3695 if (debug_threads)
87ce2a04
DE
3696 debug_printf ("already stopped LWP %ld\n",
3697 lwpid_of (lwp));
d50171e4
PA
3698
3699 /* The LWP may have been stopped in an internal event that
3700 was not meant to be notified back to GDB (e.g., gdbserver
3701 breakpoint), so we should be reporting a stop event in
3702 this case too. */
3703
3704 /* If the thread already has a pending SIGSTOP, this is a
3705 no-op. Otherwise, something later will presumably resume
3706 the thread and this will cause it to cancel any pending
3707 operation, due to last_resume_kind == resume_stop. If
3708 the thread already has a pending status to report, we
3709 will still report it the next time we wait - see
3710 status_pending_p_callback. */
1a981360
PA
3711
3712 /* If we already have a pending signal to report, then
3713 there's no need to queue a SIGSTOP, as this means we're
3714 midway through moving the LWP out of the jumppad, and we
3715 will report the pending signal as soon as that is
3716 finished. */
3717 if (lwp->pending_signals_to_report == NULL)
3718 send_sigstop (lwp);
bd99dc85 3719 }
32ca6d61 3720
bd99dc85
PA
3721 /* For stop requests, we're done. */
3722 lwp->resume = NULL;
fc7238bb 3723 thread->last_status.kind = TARGET_WAITKIND_IGNORE;
bd99dc85 3724 return 0;
5544ad89
DJ
3725 }
3726
bd99dc85
PA
3727 /* If this thread which is about to be resumed has a pending status,
3728 then don't resume any threads - we can just report the pending
3729 status. Make sure to queue any signals that would otherwise be
3730 sent. In all-stop mode, we do this decision based on if *any*
d50171e4
PA
3731 thread has a pending status. If there's a thread that needs the
3732 step-over-breakpoint dance, then don't resume any other thread
3733 but that particular one. */
3734 leave_pending = (lwp->status_pending_p || leave_all_stopped);
5544ad89 3735
d50171e4 3736 if (!leave_pending)
bd99dc85
PA
3737 {
3738 if (debug_threads)
87ce2a04 3739 debug_printf ("resuming LWP %ld\n", lwpid_of (lwp));
5544ad89 3740
d50171e4 3741 step = (lwp->resume->kind == resume_step);
2acc282a 3742 linux_resume_one_lwp (lwp, step, lwp->resume->sig, NULL);
bd99dc85
PA
3743 }
3744 else
3745 {
3746 if (debug_threads)
87ce2a04 3747 debug_printf ("leaving LWP %ld stopped\n", lwpid_of (lwp));
5544ad89 3748
bd99dc85
PA
3749 /* If we have a new signal, enqueue the signal. */
3750 if (lwp->resume->sig != 0)
3751 {
3752 struct pending_signals *p_sig;
3753 p_sig = xmalloc (sizeof (*p_sig));
3754 p_sig->prev = lwp->pending_signals;
3755 p_sig->signal = lwp->resume->sig;
3756 memset (&p_sig->info, 0, sizeof (siginfo_t));
3757
3758 /* If this is the same signal we were previously stopped by,
3759 make sure to queue its siginfo. We can ignore the return
3760 value of ptrace; if it fails, we'll skip
3761 PTRACE_SETSIGINFO. */
3762 if (WIFSTOPPED (lwp->last_status)
3763 && WSTOPSIG (lwp->last_status) == lwp->resume->sig)
b8e1b30e 3764 ptrace (PTRACE_GETSIGINFO, lwpid_of (lwp), (PTRACE_TYPE_ARG3) 0,
56f7af9c 3765 &p_sig->info);
bd99dc85
PA
3766
3767 lwp->pending_signals = p_sig;
3768 }
3769 }
5544ad89 3770
fc7238bb 3771 thread->last_status.kind = TARGET_WAITKIND_IGNORE;
bd99dc85 3772 lwp->resume = NULL;
5544ad89 3773 return 0;
0d62e5e8
DJ
3774}
3775
3776static void
2bd7c093 3777linux_resume (struct thread_resume *resume_info, size_t n)
0d62e5e8 3778{
2bd7c093 3779 struct thread_resume_array array = { resume_info, n };
d50171e4
PA
3780 struct lwp_info *need_step_over = NULL;
3781 int any_pending;
3782 int leave_all_stopped;
c6ecbae5 3783
87ce2a04
DE
3784 if (debug_threads)
3785 {
3786 debug_enter ();
3787 debug_printf ("linux_resume:\n");
3788 }
3789
2bd7c093 3790 find_inferior (&all_threads, linux_set_resume_request, &array);
5544ad89 3791
d50171e4
PA
3792 /* If there is a thread which would otherwise be resumed, which has
3793 a pending status, then don't resume any threads - we can just
3794 report the pending status. Make sure to queue any signals that
3795 would otherwise be sent. In non-stop mode, we'll apply this
3796 logic to each thread individually. We consume all pending events
3797 before considering to start a step-over (in all-stop). */
3798 any_pending = 0;
bd99dc85 3799 if (!non_stop)
d50171e4
PA
3800 find_inferior (&all_lwps, resume_status_pending_p, &any_pending);
3801
3802 /* If there is a thread which would otherwise be resumed, which is
3803 stopped at a breakpoint that needs stepping over, then don't
3804 resume any threads - have it step over the breakpoint with all
3805 other threads stopped, then resume all threads again. Make sure
3806 to queue any signals that would otherwise be delivered or
3807 queued. */
3808 if (!any_pending && supports_breakpoints ())
3809 need_step_over
3810 = (struct lwp_info *) find_inferior (&all_lwps,
3811 need_step_over_p, NULL);
3812
3813 leave_all_stopped = (need_step_over != NULL || any_pending);
3814
3815 if (debug_threads)
3816 {
3817 if (need_step_over != NULL)
87ce2a04 3818 debug_printf ("Not resuming all, need step over\n");
d50171e4 3819 else if (any_pending)
87ce2a04
DE
3820 debug_printf ("Not resuming, all-stop and found "
3821 "an LWP with pending status\n");
d50171e4 3822 else
87ce2a04 3823 debug_printf ("Resuming, no pending status or step over needed\n");
d50171e4
PA
3824 }
3825
3826 /* Even if we're leaving threads stopped, queue all signals we'd
3827 otherwise deliver. */
3828 find_inferior (&all_threads, linux_resume_one_thread, &leave_all_stopped);
3829
3830 if (need_step_over)
3831 start_step_over (need_step_over);
87ce2a04
DE
3832
3833 if (debug_threads)
3834 {
3835 debug_printf ("linux_resume done\n");
3836 debug_exit ();
3837 }
d50171e4
PA
3838}
3839
3840/* This function is called once per thread. We check the thread's
3841 last resume request, which will tell us whether to resume, step, or
3842 leave the thread stopped. Any signal the client requested to be
3843 delivered has already been enqueued at this point.
3844
3845 If any thread that GDB wants running is stopped at an internal
3846 breakpoint that needs stepping over, we start a step-over operation
3847 on that particular thread, and leave all others stopped. */
3848
7984d532
PA
3849static int
3850proceed_one_lwp (struct inferior_list_entry *entry, void *except)
d50171e4 3851{
7984d532 3852 struct lwp_info *lwp = (struct lwp_info *) entry;
8336d594 3853 struct thread_info *thread;
d50171e4
PA
3854 int step;
3855
7984d532
PA
3856 if (lwp == except)
3857 return 0;
d50171e4
PA
3858
3859 if (debug_threads)
87ce2a04 3860 debug_printf ("proceed_one_lwp: lwp %ld\n", lwpid_of (lwp));
d50171e4
PA
3861
3862 if (!lwp->stopped)
3863 {
3864 if (debug_threads)
87ce2a04 3865 debug_printf (" LWP %ld already running\n", lwpid_of (lwp));
7984d532 3866 return 0;
d50171e4
PA
3867 }
3868
8336d594
PA
3869 thread = get_lwp_thread (lwp);
3870
02fc4de7
PA
3871 if (thread->last_resume_kind == resume_stop
3872 && thread->last_status.kind != TARGET_WAITKIND_IGNORE)
d50171e4
PA
3873 {
3874 if (debug_threads)
87ce2a04
DE
3875 debug_printf (" client wants LWP to remain %ld stopped\n",
3876 lwpid_of (lwp));
7984d532 3877 return 0;
d50171e4
PA
3878 }
3879
3880 if (lwp->status_pending_p)
3881 {
3882 if (debug_threads)
87ce2a04
DE
3883 debug_printf (" LWP %ld has pending status, leaving stopped\n",
3884 lwpid_of (lwp));
7984d532 3885 return 0;
d50171e4
PA
3886 }
3887
7984d532
PA
3888 gdb_assert (lwp->suspended >= 0);
3889
d50171e4
PA
3890 if (lwp->suspended)
3891 {
3892 if (debug_threads)
87ce2a04 3893 debug_printf (" LWP %ld is suspended\n", lwpid_of (lwp));
7984d532 3894 return 0;
d50171e4
PA
3895 }
3896
1a981360
PA
3897 if (thread->last_resume_kind == resume_stop
3898 && lwp->pending_signals_to_report == NULL
3899 && lwp->collecting_fast_tracepoint == 0)
02fc4de7
PA
3900 {
3901 /* We haven't reported this LWP as stopped yet (otherwise, the
3902 last_status.kind check above would catch it, and we wouldn't
3903 reach here. This LWP may have been momentarily paused by a
3904 stop_all_lwps call while handling for example, another LWP's
3905 step-over. In that case, the pending expected SIGSTOP signal
3906 that was queued at vCont;t handling time will have already
3907 been consumed by wait_for_sigstop, and so we need to requeue
3908 another one here. Note that if the LWP already has a SIGSTOP
3909 pending, this is a no-op. */
3910
3911 if (debug_threads)
87ce2a04
DE
3912 debug_printf ("Client wants LWP %ld to stop. "
3913 "Making sure it has a SIGSTOP pending\n",
3914 lwpid_of (lwp));
02fc4de7
PA
3915
3916 send_sigstop (lwp);
3917 }
3918
8336d594 3919 step = thread->last_resume_kind == resume_step;
d50171e4 3920 linux_resume_one_lwp (lwp, step, 0, NULL);
7984d532
PA
3921 return 0;
3922}
3923
3924static int
3925unsuspend_and_proceed_one_lwp (struct inferior_list_entry *entry, void *except)
3926{
3927 struct lwp_info *lwp = (struct lwp_info *) entry;
3928
3929 if (lwp == except)
3930 return 0;
3931
3932 lwp->suspended--;
3933 gdb_assert (lwp->suspended >= 0);
3934
3935 return proceed_one_lwp (entry, except);
d50171e4
PA
3936}
3937
3938/* When we finish a step-over, set threads running again. If there's
3939 another thread that may need a step-over, now's the time to start
3940 it. Eventually, we'll move all threads past their breakpoints. */
3941
3942static void
3943proceed_all_lwps (void)
3944{
3945 struct lwp_info *need_step_over;
3946
3947 /* If there is a thread which would otherwise be resumed, which is
3948 stopped at a breakpoint that needs stepping over, then don't
3949 resume any threads - have it step over the breakpoint with all
3950 other threads stopped, then resume all threads again. */
3951
3952 if (supports_breakpoints ())
3953 {
3954 need_step_over
3955 = (struct lwp_info *) find_inferior (&all_lwps,
3956 need_step_over_p, NULL);
3957
3958 if (need_step_over != NULL)
3959 {
3960 if (debug_threads)
87ce2a04
DE
3961 debug_printf ("proceed_all_lwps: found "
3962 "thread %ld needing a step-over\n",
3963 lwpid_of (need_step_over));
d50171e4
PA
3964
3965 start_step_over (need_step_over);
3966 return;
3967 }
3968 }
5544ad89 3969
d50171e4 3970 if (debug_threads)
87ce2a04 3971 debug_printf ("Proceeding, no step-over needed\n");
d50171e4 3972
7984d532 3973 find_inferior (&all_lwps, proceed_one_lwp, NULL);
d50171e4
PA
3974}
3975
3976/* Stopped LWPs that the client wanted to be running, that don't have
3977 pending statuses, are set to run again, except for EXCEPT, if not
3978 NULL. This undoes a stop_all_lwps call. */
3979
3980static void
7984d532 3981unstop_all_lwps (int unsuspend, struct lwp_info *except)
d50171e4 3982{
5544ad89
DJ
3983 if (debug_threads)
3984 {
87ce2a04 3985 debug_enter ();
d50171e4 3986 if (except)
87ce2a04
DE
3987 debug_printf ("unstopping all lwps, except=(LWP %ld)\n",
3988 lwpid_of (except));
5544ad89 3989 else
87ce2a04 3990 debug_printf ("unstopping all lwps\n");
5544ad89
DJ
3991 }
3992
7984d532
PA
3993 if (unsuspend)
3994 find_inferior (&all_lwps, unsuspend_and_proceed_one_lwp, except);
3995 else
3996 find_inferior (&all_lwps, proceed_one_lwp, except);
87ce2a04
DE
3997
3998 if (debug_threads)
3999 {
4000 debug_printf ("unstop_all_lwps done\n");
4001 debug_exit ();
4002 }
0d62e5e8
DJ
4003}
4004
58caa3dc
DJ
4005
4006#ifdef HAVE_LINUX_REGSETS
4007
1faeff08
MR
4008#define use_linux_regsets 1
4009
030031ee
PA
4010/* Returns true if REGSET has been disabled. */
4011
4012static int
4013regset_disabled (struct regsets_info *info, struct regset_info *regset)
4014{
4015 return (info->disabled_regsets != NULL
4016 && info->disabled_regsets[regset - info->regsets]);
4017}
4018
4019/* Disable REGSET. */
4020
4021static void
4022disable_regset (struct regsets_info *info, struct regset_info *regset)
4023{
4024 int dr_offset;
4025
4026 dr_offset = regset - info->regsets;
4027 if (info->disabled_regsets == NULL)
4028 info->disabled_regsets = xcalloc (1, info->num_regsets);
4029 info->disabled_regsets[dr_offset] = 1;
4030}
4031
58caa3dc 4032static int
3aee8918
PA
4033regsets_fetch_inferior_registers (struct regsets_info *regsets_info,
4034 struct regcache *regcache)
58caa3dc
DJ
4035{
4036 struct regset_info *regset;
e9d25b98 4037 int saw_general_regs = 0;
95954743 4038 int pid;
1570b33e 4039 struct iovec iov;
58caa3dc 4040
3aee8918 4041 regset = regsets_info->regsets;
58caa3dc 4042
95954743 4043 pid = lwpid_of (get_thread_lwp (current_inferior));
58caa3dc
DJ
4044 while (regset->size >= 0)
4045 {
1570b33e
L
4046 void *buf, *data;
4047 int nt_type, res;
58caa3dc 4048
030031ee 4049 if (regset->size == 0 || regset_disabled (regsets_info, regset))
58caa3dc
DJ
4050 {
4051 regset ++;
4052 continue;
4053 }
4054
bca929d3 4055 buf = xmalloc (regset->size);
1570b33e
L
4056
4057 nt_type = regset->nt_type;
4058 if (nt_type)
4059 {
4060 iov.iov_base = buf;
4061 iov.iov_len = regset->size;
4062 data = (void *) &iov;
4063 }
4064 else
4065 data = buf;
4066
dfb64f85 4067#ifndef __sparc__
f15f9948 4068 res = ptrace (regset->get_request, pid,
b8e1b30e 4069 (PTRACE_TYPE_ARG3) (long) nt_type, data);
dfb64f85 4070#else
1570b33e 4071 res = ptrace (regset->get_request, pid, data, nt_type);
dfb64f85 4072#endif
58caa3dc
DJ
4073 if (res < 0)
4074 {
4075 if (errno == EIO)
4076 {
52fa2412 4077 /* If we get EIO on a regset, do not try it again for
3aee8918 4078 this process mode. */
030031ee 4079 disable_regset (regsets_info, regset);
fdeb2a12 4080 free (buf);
52fa2412 4081 continue;
58caa3dc
DJ
4082 }
4083 else
4084 {
0d62e5e8 4085 char s[256];
95954743
PA
4086 sprintf (s, "ptrace(regsets_fetch_inferior_registers) PID=%d",
4087 pid);
0d62e5e8 4088 perror (s);
58caa3dc
DJ
4089 }
4090 }
e9d25b98
DJ
4091 else if (regset->type == GENERAL_REGS)
4092 saw_general_regs = 1;
442ea881 4093 regset->store_function (regcache, buf);
58caa3dc 4094 regset ++;
fdeb2a12 4095 free (buf);
58caa3dc 4096 }
e9d25b98
DJ
4097 if (saw_general_regs)
4098 return 0;
4099 else
4100 return 1;
58caa3dc
DJ
4101}
4102
4103static int
3aee8918
PA
4104regsets_store_inferior_registers (struct regsets_info *regsets_info,
4105 struct regcache *regcache)
58caa3dc
DJ
4106{
4107 struct regset_info *regset;
e9d25b98 4108 int saw_general_regs = 0;
95954743 4109 int pid;
1570b33e 4110 struct iovec iov;
58caa3dc 4111
3aee8918 4112 regset = regsets_info->regsets;
58caa3dc 4113
95954743 4114 pid = lwpid_of (get_thread_lwp (current_inferior));
58caa3dc
DJ
4115 while (regset->size >= 0)
4116 {
1570b33e
L
4117 void *buf, *data;
4118 int nt_type, res;
58caa3dc 4119
030031ee 4120 if (regset->size == 0 || regset_disabled (regsets_info, regset))
58caa3dc
DJ
4121 {
4122 regset ++;
4123 continue;
4124 }
4125
bca929d3 4126 buf = xmalloc (regset->size);
545587ee
DJ
4127
4128 /* First fill the buffer with the current register set contents,
4129 in case there are any items in the kernel's regset that are
4130 not in gdbserver's regcache. */
1570b33e
L
4131
4132 nt_type = regset->nt_type;
4133 if (nt_type)
4134 {
4135 iov.iov_base = buf;
4136 iov.iov_len = regset->size;
4137 data = (void *) &iov;
4138 }
4139 else
4140 data = buf;
4141
dfb64f85 4142#ifndef __sparc__
f15f9948 4143 res = ptrace (regset->get_request, pid,
b8e1b30e 4144 (PTRACE_TYPE_ARG3) (long) nt_type, data);
dfb64f85 4145#else
689cc2ae 4146 res = ptrace (regset->get_request, pid, data, nt_type);
dfb64f85 4147#endif
545587ee
DJ
4148
4149 if (res == 0)
4150 {
4151 /* Then overlay our cached registers on that. */
442ea881 4152 regset->fill_function (regcache, buf);
545587ee
DJ
4153
4154 /* Only now do we write the register set. */
dfb64f85 4155#ifndef __sparc__
f15f9948 4156 res = ptrace (regset->set_request, pid,
b8e1b30e 4157 (PTRACE_TYPE_ARG3) (long) nt_type, data);
dfb64f85 4158#else
1570b33e 4159 res = ptrace (regset->set_request, pid, data, nt_type);
dfb64f85 4160#endif
545587ee
DJ
4161 }
4162
58caa3dc
DJ
4163 if (res < 0)
4164 {
4165 if (errno == EIO)
4166 {
52fa2412 4167 /* If we get EIO on a regset, do not try it again for
3aee8918 4168 this process mode. */
030031ee 4169 disable_regset (regsets_info, regset);
fdeb2a12 4170 free (buf);
52fa2412 4171 continue;
58caa3dc 4172 }
3221518c
UW
4173 else if (errno == ESRCH)
4174 {
1b3f6016
PA
4175 /* At this point, ESRCH should mean the process is
4176 already gone, in which case we simply ignore attempts
4177 to change its registers. See also the related
4178 comment in linux_resume_one_lwp. */
fdeb2a12 4179 free (buf);
3221518c
UW
4180 return 0;
4181 }
58caa3dc
DJ
4182 else
4183 {
ce3a066d 4184 perror ("Warning: ptrace(regsets_store_inferior_registers)");
58caa3dc
DJ
4185 }
4186 }
e9d25b98
DJ
4187 else if (regset->type == GENERAL_REGS)
4188 saw_general_regs = 1;
58caa3dc 4189 regset ++;
09ec9b38 4190 free (buf);
58caa3dc 4191 }
e9d25b98
DJ
4192 if (saw_general_regs)
4193 return 0;
4194 else
4195 return 1;
58caa3dc
DJ
4196}
4197
1faeff08 4198#else /* !HAVE_LINUX_REGSETS */
58caa3dc 4199
1faeff08 4200#define use_linux_regsets 0
3aee8918
PA
4201#define regsets_fetch_inferior_registers(regsets_info, regcache) 1
4202#define regsets_store_inferior_registers(regsets_info, regcache) 1
58caa3dc 4203
58caa3dc 4204#endif
1faeff08
MR
4205
4206/* Return 1 if register REGNO is supported by one of the regset ptrace
4207 calls or 0 if it has to be transferred individually. */
4208
4209static int
3aee8918 4210linux_register_in_regsets (const struct regs_info *regs_info, int regno)
1faeff08
MR
4211{
4212 unsigned char mask = 1 << (regno % 8);
4213 size_t index = regno / 8;
4214
4215 return (use_linux_regsets
3aee8918
PA
4216 && (regs_info->regset_bitmap == NULL
4217 || (regs_info->regset_bitmap[index] & mask) != 0));
1faeff08
MR
4218}
4219
58caa3dc 4220#ifdef HAVE_LINUX_USRREGS
1faeff08
MR
4221
4222int
3aee8918 4223register_addr (const struct usrregs_info *usrregs, int regnum)
1faeff08
MR
4224{
4225 int addr;
4226
3aee8918 4227 if (regnum < 0 || regnum >= usrregs->num_regs)
1faeff08
MR
4228 error ("Invalid register number %d.", regnum);
4229
3aee8918 4230 addr = usrregs->regmap[regnum];
1faeff08
MR
4231
4232 return addr;
4233}
4234
4235/* Fetch one register. */
4236static void
3aee8918
PA
4237fetch_register (const struct usrregs_info *usrregs,
4238 struct regcache *regcache, int regno)
1faeff08
MR
4239{
4240 CORE_ADDR regaddr;
4241 int i, size;
4242 char *buf;
4243 int pid;
4244
3aee8918 4245 if (regno >= usrregs->num_regs)
1faeff08
MR
4246 return;
4247 if ((*the_low_target.cannot_fetch_register) (regno))
4248 return;
4249
3aee8918 4250 regaddr = register_addr (usrregs, regno);
1faeff08
MR
4251 if (regaddr == -1)
4252 return;
4253
3aee8918
PA
4254 size = ((register_size (regcache->tdesc, regno)
4255 + sizeof (PTRACE_XFER_TYPE) - 1)
1faeff08
MR
4256 & -sizeof (PTRACE_XFER_TYPE));
4257 buf = alloca (size);
4258
4259 pid = lwpid_of (get_thread_lwp (current_inferior));
4260 for (i = 0; i < size; i += sizeof (PTRACE_XFER_TYPE))
4261 {
4262 errno = 0;
4263 *(PTRACE_XFER_TYPE *) (buf + i) =
4264 ptrace (PTRACE_PEEKUSER, pid,
4265 /* Coerce to a uintptr_t first to avoid potential gcc warning
4266 of coercing an 8 byte integer to a 4 byte pointer. */
b8e1b30e 4267 (PTRACE_TYPE_ARG3) (uintptr_t) regaddr, (PTRACE_TYPE_ARG4) 0);
1faeff08
MR
4268 regaddr += sizeof (PTRACE_XFER_TYPE);
4269 if (errno != 0)
4270 error ("reading register %d: %s", regno, strerror (errno));
4271 }
4272
4273 if (the_low_target.supply_ptrace_register)
4274 the_low_target.supply_ptrace_register (regcache, regno, buf);
4275 else
4276 supply_register (regcache, regno, buf);
4277}
4278
4279/* Store one register. */
4280static void
3aee8918
PA
4281store_register (const struct usrregs_info *usrregs,
4282 struct regcache *regcache, int regno)
1faeff08
MR
4283{
4284 CORE_ADDR regaddr;
4285 int i, size;
4286 char *buf;
4287 int pid;
4288
3aee8918 4289 if (regno >= usrregs->num_regs)
1faeff08
MR
4290 return;
4291 if ((*the_low_target.cannot_store_register) (regno))
4292 return;
4293
3aee8918 4294 regaddr = register_addr (usrregs, regno);
1faeff08
MR
4295 if (regaddr == -1)
4296 return;
4297
3aee8918
PA
4298 size = ((register_size (regcache->tdesc, regno)
4299 + sizeof (PTRACE_XFER_TYPE) - 1)
1faeff08
MR
4300 & -sizeof (PTRACE_XFER_TYPE));
4301 buf = alloca (size);
4302 memset (buf, 0, size);
4303
4304 if (the_low_target.collect_ptrace_register)
4305 the_low_target.collect_ptrace_register (regcache, regno, buf);
4306 else
4307 collect_register (regcache, regno, buf);
4308
4309 pid = lwpid_of (get_thread_lwp (current_inferior));
4310 for (i = 0; i < size; i += sizeof (PTRACE_XFER_TYPE))
4311 {
4312 errno = 0;
4313 ptrace (PTRACE_POKEUSER, pid,
4314 /* Coerce to a uintptr_t first to avoid potential gcc warning
4315 about coercing an 8 byte integer to a 4 byte pointer. */
b8e1b30e
LM
4316 (PTRACE_TYPE_ARG3) (uintptr_t) regaddr,
4317 (PTRACE_TYPE_ARG4) *(PTRACE_XFER_TYPE *) (buf + i));
1faeff08
MR
4318 if (errno != 0)
4319 {
4320 /* At this point, ESRCH should mean the process is
4321 already gone, in which case we simply ignore attempts
4322 to change its registers. See also the related
4323 comment in linux_resume_one_lwp. */
4324 if (errno == ESRCH)
4325 return;
4326
4327 if ((*the_low_target.cannot_store_register) (regno) == 0)
4328 error ("writing register %d: %s", regno, strerror (errno));
4329 }
4330 regaddr += sizeof (PTRACE_XFER_TYPE);
4331 }
4332}
4333
4334/* Fetch all registers, or just one, from the child process.
4335 If REGNO is -1, do this for all registers, skipping any that are
4336 assumed to have been retrieved by regsets_fetch_inferior_registers,
4337 unless ALL is non-zero.
4338 Otherwise, REGNO specifies which register (so we can save time). */
4339static void
3aee8918
PA
4340usr_fetch_inferior_registers (const struct regs_info *regs_info,
4341 struct regcache *regcache, int regno, int all)
1faeff08 4342{
3aee8918
PA
4343 struct usrregs_info *usr = regs_info->usrregs;
4344
1faeff08
MR
4345 if (regno == -1)
4346 {
3aee8918
PA
4347 for (regno = 0; regno < usr->num_regs; regno++)
4348 if (all || !linux_register_in_regsets (regs_info, regno))
4349 fetch_register (usr, regcache, regno);
1faeff08
MR
4350 }
4351 else
3aee8918 4352 fetch_register (usr, regcache, regno);
1faeff08
MR
4353}
4354
4355/* Store our register values back into the inferior.
4356 If REGNO is -1, do this for all registers, skipping any that are
4357 assumed to have been saved by regsets_store_inferior_registers,
4358 unless ALL is non-zero.
4359 Otherwise, REGNO specifies which register (so we can save time). */
4360static void
3aee8918
PA
4361usr_store_inferior_registers (const struct regs_info *regs_info,
4362 struct regcache *regcache, int regno, int all)
1faeff08 4363{
3aee8918
PA
4364 struct usrregs_info *usr = regs_info->usrregs;
4365
1faeff08
MR
4366 if (regno == -1)
4367 {
3aee8918
PA
4368 for (regno = 0; regno < usr->num_regs; regno++)
4369 if (all || !linux_register_in_regsets (regs_info, regno))
4370 store_register (usr, regcache, regno);
1faeff08
MR
4371 }
4372 else
3aee8918 4373 store_register (usr, regcache, regno);
1faeff08
MR
4374}
4375
4376#else /* !HAVE_LINUX_USRREGS */
4377
3aee8918
PA
4378#define usr_fetch_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
4379#define usr_store_inferior_registers(regs_info, regcache, regno, all) do {} while (0)
1faeff08 4380
58caa3dc 4381#endif
1faeff08
MR
4382
4383
4384void
4385linux_fetch_registers (struct regcache *regcache, int regno)
4386{
4387 int use_regsets;
4388 int all = 0;
3aee8918 4389 const struct regs_info *regs_info = (*the_low_target.regs_info) ();
1faeff08
MR
4390
4391 if (regno == -1)
4392 {
3aee8918
PA
4393 if (the_low_target.fetch_register != NULL
4394 && regs_info->usrregs != NULL)
4395 for (regno = 0; regno < regs_info->usrregs->num_regs; regno++)
c14dfd32
PA
4396 (*the_low_target.fetch_register) (regcache, regno);
4397
3aee8918
PA
4398 all = regsets_fetch_inferior_registers (regs_info->regsets_info, regcache);
4399 if (regs_info->usrregs != NULL)
4400 usr_fetch_inferior_registers (regs_info, regcache, -1, all);
1faeff08
MR
4401 }
4402 else
4403 {
c14dfd32
PA
4404 if (the_low_target.fetch_register != NULL
4405 && (*the_low_target.fetch_register) (regcache, regno))
4406 return;
4407
3aee8918 4408 use_regsets = linux_register_in_regsets (regs_info, regno);
1faeff08 4409 if (use_regsets)
3aee8918
PA
4410 all = regsets_fetch_inferior_registers (regs_info->regsets_info,
4411 regcache);
4412 if ((!use_regsets || all) && regs_info->usrregs != NULL)
4413 usr_fetch_inferior_registers (regs_info, regcache, regno, 1);
1faeff08 4414 }
58caa3dc
DJ
4415}
4416
4417void
442ea881 4418linux_store_registers (struct regcache *regcache, int regno)
58caa3dc 4419{
1faeff08
MR
4420 int use_regsets;
4421 int all = 0;
3aee8918 4422 const struct regs_info *regs_info = (*the_low_target.regs_info) ();
1faeff08
MR
4423
4424 if (regno == -1)
4425 {
3aee8918
PA
4426 all = regsets_store_inferior_registers (regs_info->regsets_info,
4427 regcache);
4428 if (regs_info->usrregs != NULL)
4429 usr_store_inferior_registers (regs_info, regcache, regno, all);
1faeff08
MR
4430 }
4431 else
4432 {
3aee8918 4433 use_regsets = linux_register_in_regsets (regs_info, regno);
1faeff08 4434 if (use_regsets)
3aee8918
PA
4435 all = regsets_store_inferior_registers (regs_info->regsets_info,
4436 regcache);
4437 if ((!use_regsets || all) && regs_info->usrregs != NULL)
4438 usr_store_inferior_registers (regs_info, regcache, regno, 1);
1faeff08 4439 }
58caa3dc
DJ
4440}
4441
da6d8c04 4442
da6d8c04
DJ
4443/* Copy LEN bytes from inferior's memory starting at MEMADDR
4444 to debugger memory starting at MYADDR. */
4445
c3e735a6 4446static int
f450004a 4447linux_read_memory (CORE_ADDR memaddr, unsigned char *myaddr, int len)
da6d8c04 4448{
4934b29e
MR
4449 int pid = lwpid_of (get_thread_lwp (current_inferior));
4450 register PTRACE_XFER_TYPE *buffer;
4451 register CORE_ADDR addr;
4452 register int count;
4453 char filename[64];
da6d8c04 4454 register int i;
4934b29e 4455 int ret;
fd462a61 4456 int fd;
fd462a61
DJ
4457
4458 /* Try using /proc. Don't bother for one word. */
4459 if (len >= 3 * sizeof (long))
4460 {
4934b29e
MR
4461 int bytes;
4462
fd462a61
DJ
4463 /* We could keep this file open and cache it - possibly one per
4464 thread. That requires some juggling, but is even faster. */
95954743 4465 sprintf (filename, "/proc/%d/mem", pid);
fd462a61
DJ
4466 fd = open (filename, O_RDONLY | O_LARGEFILE);
4467 if (fd == -1)
4468 goto no_proc;
4469
4470 /* If pread64 is available, use it. It's faster if the kernel
4471 supports it (only one syscall), and it's 64-bit safe even on
4472 32-bit platforms (for instance, SPARC debugging a SPARC64
4473 application). */
4474#ifdef HAVE_PREAD64
4934b29e 4475 bytes = pread64 (fd, myaddr, len, memaddr);
fd462a61 4476#else
4934b29e
MR
4477 bytes = -1;
4478 if (lseek (fd, memaddr, SEEK_SET) != -1)
4479 bytes = read (fd, myaddr, len);
fd462a61 4480#endif
fd462a61
DJ
4481
4482 close (fd);
4934b29e
MR
4483 if (bytes == len)
4484 return 0;
4485
4486 /* Some data was read, we'll try to get the rest with ptrace. */
4487 if (bytes > 0)
4488 {
4489 memaddr += bytes;
4490 myaddr += bytes;
4491 len -= bytes;
4492 }
fd462a61 4493 }
da6d8c04 4494
fd462a61 4495 no_proc:
4934b29e
MR
4496 /* Round starting address down to longword boundary. */
4497 addr = memaddr & -(CORE_ADDR) sizeof (PTRACE_XFER_TYPE);
4498 /* Round ending address up; get number of longwords that makes. */
4499 count = ((((memaddr + len) - addr) + sizeof (PTRACE_XFER_TYPE) - 1)
4500 / sizeof (PTRACE_XFER_TYPE));
4501 /* Allocate buffer of that many longwords. */
4502 buffer = (PTRACE_XFER_TYPE *) alloca (count * sizeof (PTRACE_XFER_TYPE));
4503
da6d8c04 4504 /* Read all the longwords */
4934b29e 4505 errno = 0;
da6d8c04
DJ
4506 for (i = 0; i < count; i++, addr += sizeof (PTRACE_XFER_TYPE))
4507 {
14ce3065
DE
4508 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
4509 about coercing an 8 byte integer to a 4 byte pointer. */
4510 buffer[i] = ptrace (PTRACE_PEEKTEXT, pid,
b8e1b30e
LM
4511 (PTRACE_TYPE_ARG3) (uintptr_t) addr,
4512 (PTRACE_TYPE_ARG4) 0);
c3e735a6 4513 if (errno)
4934b29e 4514 break;
da6d8c04 4515 }
4934b29e 4516 ret = errno;
da6d8c04
DJ
4517
4518 /* Copy appropriate bytes out of the buffer. */
8d409d16
MR
4519 if (i > 0)
4520 {
4521 i *= sizeof (PTRACE_XFER_TYPE);
4522 i -= memaddr & (sizeof (PTRACE_XFER_TYPE) - 1);
4523 memcpy (myaddr,
4524 (char *) buffer + (memaddr & (sizeof (PTRACE_XFER_TYPE) - 1)),
4525 i < len ? i : len);
4526 }
c3e735a6 4527
4934b29e 4528 return ret;
da6d8c04
DJ
4529}
4530
93ae6fdc
PA
4531/* Copy LEN bytes of data from debugger memory at MYADDR to inferior's
4532 memory at MEMADDR. On failure (cannot write to the inferior)
f0ae6fc3 4533 returns the value of errno. Always succeeds if LEN is zero. */
da6d8c04 4534
ce3a066d 4535static int
f450004a 4536linux_write_memory (CORE_ADDR memaddr, const unsigned char *myaddr, int len)
da6d8c04
DJ
4537{
4538 register int i;
4539 /* Round starting address down to longword boundary. */
4540 register CORE_ADDR addr = memaddr & -(CORE_ADDR) sizeof (PTRACE_XFER_TYPE);
4541 /* Round ending address up; get number of longwords that makes. */
4542 register int count
493e2a69
MS
4543 = (((memaddr + len) - addr) + sizeof (PTRACE_XFER_TYPE) - 1)
4544 / sizeof (PTRACE_XFER_TYPE);
4545
da6d8c04 4546 /* Allocate buffer of that many longwords. */
493e2a69
MS
4547 register PTRACE_XFER_TYPE *buffer = (PTRACE_XFER_TYPE *)
4548 alloca (count * sizeof (PTRACE_XFER_TYPE));
4549
95954743 4550 int pid = lwpid_of (get_thread_lwp (current_inferior));
da6d8c04 4551
f0ae6fc3
PA
4552 if (len == 0)
4553 {
4554 /* Zero length write always succeeds. */
4555 return 0;
4556 }
4557
0d62e5e8
DJ
4558 if (debug_threads)
4559 {
58d6951d
DJ
4560 /* Dump up to four bytes. */
4561 unsigned int val = * (unsigned int *) myaddr;
4562 if (len == 1)
4563 val = val & 0xff;
4564 else if (len == 2)
4565 val = val & 0xffff;
4566 else if (len == 3)
4567 val = val & 0xffffff;
87ce2a04
DE
4568 debug_printf ("Writing %0*x to 0x%08lx\n", 2 * ((len < 4) ? len : 4),
4569 val, (long)memaddr);
0d62e5e8
DJ
4570 }
4571
da6d8c04
DJ
4572 /* Fill start and end extra bytes of buffer with existing memory data. */
4573
93ae6fdc 4574 errno = 0;
14ce3065
DE
4575 /* Coerce the 3rd arg to a uintptr_t first to avoid potential gcc warning
4576 about coercing an 8 byte integer to a 4 byte pointer. */
4577 buffer[0] = ptrace (PTRACE_PEEKTEXT, pid,
b8e1b30e
LM
4578 (PTRACE_TYPE_ARG3) (uintptr_t) addr,
4579 (PTRACE_TYPE_ARG4) 0);
93ae6fdc
PA
4580 if (errno)
4581 return errno;
da6d8c04
DJ
4582
4583 if (count > 1)
4584 {
93ae6fdc 4585 errno = 0;
da6d8c04 4586 buffer[count - 1]
95954743 4587 = ptrace (PTRACE_PEEKTEXT, pid,
14ce3065
DE
4588 /* Coerce to a uintptr_t first to avoid potential gcc warning
4589 about coercing an 8 byte integer to a 4 byte pointer. */
b8e1b30e 4590 (PTRACE_TYPE_ARG3) (uintptr_t) (addr + (count - 1)
14ce3065 4591 * sizeof (PTRACE_XFER_TYPE)),
b8e1b30e 4592 (PTRACE_TYPE_ARG4) 0);
93ae6fdc
PA
4593 if (errno)
4594 return errno;
da6d8c04
DJ
4595 }
4596
93ae6fdc 4597 /* Copy data to be written over corresponding part of buffer. */
da6d8c04 4598
493e2a69
MS
4599 memcpy ((char *) buffer + (memaddr & (sizeof (PTRACE_XFER_TYPE) - 1)),
4600 myaddr, len);
da6d8c04
DJ
4601
4602 /* Write the entire buffer. */
4603
4604 for (i = 0; i < count; i++, addr += sizeof (PTRACE_XFER_TYPE))
4605 {
4606 errno = 0;
14ce3065
DE
4607 ptrace (PTRACE_POKETEXT, pid,
4608 /* Coerce to a uintptr_t first to avoid potential gcc warning
4609 about coercing an 8 byte integer to a 4 byte pointer. */
b8e1b30e
LM
4610 (PTRACE_TYPE_ARG3) (uintptr_t) addr,
4611 (PTRACE_TYPE_ARG4) buffer[i]);
da6d8c04
DJ
4612 if (errno)
4613 return errno;
4614 }
4615
4616 return 0;
4617}
2f2893d9
DJ
4618
4619static void
4620linux_look_up_symbols (void)
4621{
0d62e5e8 4622#ifdef USE_THREAD_DB
95954743
PA
4623 struct process_info *proc = current_process ();
4624
cdbfd419 4625 if (proc->private->thread_db != NULL)
0d62e5e8
DJ
4626 return;
4627
96d7229d
LM
4628 /* If the kernel supports tracing clones, then we don't need to
4629 use the magic thread event breakpoint to learn about
4630 threads. */
4631 thread_db_init (!linux_supports_traceclone ());
0d62e5e8
DJ
4632#endif
4633}
4634
e5379b03 4635static void
ef57601b 4636linux_request_interrupt (void)
e5379b03 4637{
a1928bad 4638 extern unsigned long signal_pid;
e5379b03 4639
95954743
PA
4640 if (!ptid_equal (cont_thread, null_ptid)
4641 && !ptid_equal (cont_thread, minus_one_ptid))
e5379b03 4642 {
54a0b537 4643 struct lwp_info *lwp;
bd99dc85 4644 int lwpid;
e5379b03 4645
54a0b537 4646 lwp = get_thread_lwp (current_inferior);
bd99dc85
PA
4647 lwpid = lwpid_of (lwp);
4648 kill_lwp (lwpid, SIGINT);
e5379b03
DJ
4649 }
4650 else
ef57601b 4651 kill_lwp (signal_pid, SIGINT);
e5379b03
DJ
4652}
4653
aa691b87
RM
4654/* Copy LEN bytes from inferior's auxiliary vector starting at OFFSET
4655 to debugger memory starting at MYADDR. */
4656
4657static int
f450004a 4658linux_read_auxv (CORE_ADDR offset, unsigned char *myaddr, unsigned int len)
aa691b87
RM
4659{
4660 char filename[PATH_MAX];
4661 int fd, n;
95954743 4662 int pid = lwpid_of (get_thread_lwp (current_inferior));
aa691b87 4663
6cebaf6e 4664 xsnprintf (filename, sizeof filename, "/proc/%d/auxv", pid);
aa691b87
RM
4665
4666 fd = open (filename, O_RDONLY);
4667 if (fd < 0)
4668 return -1;
4669
4670 if (offset != (CORE_ADDR) 0
4671 && lseek (fd, (off_t) offset, SEEK_SET) != (off_t) offset)
4672 n = -1;
4673 else
4674 n = read (fd, myaddr, len);
4675
4676 close (fd);
4677
4678 return n;
4679}
4680
d993e290
PA
4681/* These breakpoint and watchpoint related wrapper functions simply
4682 pass on the function call if the target has registered a
4683 corresponding function. */
e013ee27
OF
4684
4685static int
d993e290 4686linux_insert_point (char type, CORE_ADDR addr, int len)
e013ee27 4687{
d993e290
PA
4688 if (the_low_target.insert_point != NULL)
4689 return the_low_target.insert_point (type, addr, len);
e013ee27
OF
4690 else
4691 /* Unsupported (see target.h). */
4692 return 1;
4693}
4694
4695static int
d993e290 4696linux_remove_point (char type, CORE_ADDR addr, int len)
e013ee27 4697{
d993e290
PA
4698 if (the_low_target.remove_point != NULL)
4699 return the_low_target.remove_point (type, addr, len);
e013ee27
OF
4700 else
4701 /* Unsupported (see target.h). */
4702 return 1;
4703}
4704
4705static int
4706linux_stopped_by_watchpoint (void)
4707{
c3adc08c
PA
4708 struct lwp_info *lwp = get_thread_lwp (current_inferior);
4709
4710 return lwp->stopped_by_watchpoint;
e013ee27
OF
4711}
4712
4713static CORE_ADDR
4714linux_stopped_data_address (void)
4715{
c3adc08c
PA
4716 struct lwp_info *lwp = get_thread_lwp (current_inferior);
4717
4718 return lwp->stopped_data_address;
e013ee27
OF
4719}
4720
db0dfaa0
LM
4721#if defined(__UCLIBC__) && defined(HAS_NOMMU) \
4722 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
4723 && defined(PT_TEXT_END_ADDR)
4724
4725/* This is only used for targets that define PT_TEXT_ADDR,
4726 PT_DATA_ADDR and PT_TEXT_END_ADDR. If those are not defined, supposedly
4727 the target has different ways of acquiring this information, like
4728 loadmaps. */
52fb6437
NS
4729
4730/* Under uClinux, programs are loaded at non-zero offsets, which we need
4731 to tell gdb about. */
4732
4733static int
4734linux_read_offsets (CORE_ADDR *text_p, CORE_ADDR *data_p)
4735{
52fb6437 4736 unsigned long text, text_end, data;
bd99dc85 4737 int pid = lwpid_of (get_thread_lwp (current_inferior));
52fb6437
NS
4738
4739 errno = 0;
4740
b8e1b30e
LM
4741 text = ptrace (PTRACE_PEEKUSER, pid, (PTRACE_TYPE_ARG3) PT_TEXT_ADDR,
4742 (PTRACE_TYPE_ARG4) 0);
4743 text_end = ptrace (PTRACE_PEEKUSER, pid, (PTRACE_TYPE_ARG3) PT_TEXT_END_ADDR,
4744 (PTRACE_TYPE_ARG4) 0);
4745 data = ptrace (PTRACE_PEEKUSER, pid, (PTRACE_TYPE_ARG3) PT_DATA_ADDR,
4746 (PTRACE_TYPE_ARG4) 0);
52fb6437
NS
4747
4748 if (errno == 0)
4749 {
4750 /* Both text and data offsets produced at compile-time (and so
1b3f6016
PA
4751 used by gdb) are relative to the beginning of the program,
4752 with the data segment immediately following the text segment.
4753 However, the actual runtime layout in memory may put the data
4754 somewhere else, so when we send gdb a data base-address, we
4755 use the real data base address and subtract the compile-time
4756 data base-address from it (which is just the length of the
4757 text segment). BSS immediately follows data in both
4758 cases. */
52fb6437
NS
4759 *text_p = text;
4760 *data_p = data - (text_end - text);
1b3f6016 4761
52fb6437
NS
4762 return 1;
4763 }
52fb6437
NS
4764 return 0;
4765}
4766#endif
4767
07e059b5
VP
4768static int
4769linux_qxfer_osdata (const char *annex,
1b3f6016
PA
4770 unsigned char *readbuf, unsigned const char *writebuf,
4771 CORE_ADDR offset, int len)
07e059b5 4772{
d26e3629 4773 return linux_common_xfer_osdata (annex, readbuf, offset, len);
07e059b5
VP
4774}
4775
d0722149
DE
4776/* Convert a native/host siginfo object, into/from the siginfo in the
4777 layout of the inferiors' architecture. */
4778
4779static void
a5362b9a 4780siginfo_fixup (siginfo_t *siginfo, void *inf_siginfo, int direction)
d0722149
DE
4781{
4782 int done = 0;
4783
4784 if (the_low_target.siginfo_fixup != NULL)
4785 done = the_low_target.siginfo_fixup (siginfo, inf_siginfo, direction);
4786
4787 /* If there was no callback, or the callback didn't do anything,
4788 then just do a straight memcpy. */
4789 if (!done)
4790 {
4791 if (direction == 1)
a5362b9a 4792 memcpy (siginfo, inf_siginfo, sizeof (siginfo_t));
d0722149 4793 else
a5362b9a 4794 memcpy (inf_siginfo, siginfo, sizeof (siginfo_t));
d0722149
DE
4795 }
4796}
4797
4aa995e1
PA
4798static int
4799linux_xfer_siginfo (const char *annex, unsigned char *readbuf,
4800 unsigned const char *writebuf, CORE_ADDR offset, int len)
4801{
d0722149 4802 int pid;
a5362b9a
TS
4803 siginfo_t siginfo;
4804 char inf_siginfo[sizeof (siginfo_t)];
4aa995e1
PA
4805
4806 if (current_inferior == NULL)
4807 return -1;
4808
bd99dc85 4809 pid = lwpid_of (get_thread_lwp (current_inferior));
4aa995e1
PA
4810
4811 if (debug_threads)
87ce2a04
DE
4812 debug_printf ("%s siginfo for lwp %d.\n",
4813 readbuf != NULL ? "Reading" : "Writing",
4814 pid);
4aa995e1 4815
0adea5f7 4816 if (offset >= sizeof (siginfo))
4aa995e1
PA
4817 return -1;
4818
b8e1b30e 4819 if (ptrace (PTRACE_GETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo) != 0)
4aa995e1
PA
4820 return -1;
4821
d0722149
DE
4822 /* When GDBSERVER is built as a 64-bit application, ptrace writes into
4823 SIGINFO an object with 64-bit layout. Since debugging a 32-bit
4824 inferior with a 64-bit GDBSERVER should look the same as debugging it
4825 with a 32-bit GDBSERVER, we need to convert it. */
4826 siginfo_fixup (&siginfo, inf_siginfo, 0);
4827
4aa995e1
PA
4828 if (offset + len > sizeof (siginfo))
4829 len = sizeof (siginfo) - offset;
4830
4831 if (readbuf != NULL)
d0722149 4832 memcpy (readbuf, inf_siginfo + offset, len);
4aa995e1
PA
4833 else
4834 {
d0722149
DE
4835 memcpy (inf_siginfo + offset, writebuf, len);
4836
4837 /* Convert back to ptrace layout before flushing it out. */
4838 siginfo_fixup (&siginfo, inf_siginfo, 1);
4839
b8e1b30e 4840 if (ptrace (PTRACE_SETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo) != 0)
4aa995e1
PA
4841 return -1;
4842 }
4843
4844 return len;
4845}
4846
bd99dc85
PA
4847/* SIGCHLD handler that serves two purposes: In non-stop/async mode,
4848 so we notice when children change state; as the handler for the
4849 sigsuspend in my_waitpid. */
4850
4851static void
4852sigchld_handler (int signo)
4853{
4854 int old_errno = errno;
4855
4856 if (debug_threads)
e581f2b4
PA
4857 {
4858 do
4859 {
4860 /* fprintf is not async-signal-safe, so call write
4861 directly. */
4862 if (write (2, "sigchld_handler\n",
4863 sizeof ("sigchld_handler\n") - 1) < 0)
4864 break; /* just ignore */
4865 } while (0);
4866 }
bd99dc85
PA
4867
4868 if (target_is_async_p ())
4869 async_file_mark (); /* trigger a linux_wait */
4870
4871 errno = old_errno;
4872}
4873
4874static int
4875linux_supports_non_stop (void)
4876{
4877 return 1;
4878}
4879
4880static int
4881linux_async (int enable)
4882{
4883 int previous = (linux_event_pipe[0] != -1);
4884
8336d594 4885 if (debug_threads)
87ce2a04
DE
4886 debug_printf ("linux_async (%d), previous=%d\n",
4887 enable, previous);
8336d594 4888
bd99dc85
PA
4889 if (previous != enable)
4890 {
4891 sigset_t mask;
4892 sigemptyset (&mask);
4893 sigaddset (&mask, SIGCHLD);
4894
4895 sigprocmask (SIG_BLOCK, &mask, NULL);
4896
4897 if (enable)
4898 {
4899 if (pipe (linux_event_pipe) == -1)
4900 fatal ("creating event pipe failed.");
4901
4902 fcntl (linux_event_pipe[0], F_SETFL, O_NONBLOCK);
4903 fcntl (linux_event_pipe[1], F_SETFL, O_NONBLOCK);
4904
4905 /* Register the event loop handler. */
4906 add_file_handler (linux_event_pipe[0],
4907 handle_target_event, NULL);
4908
4909 /* Always trigger a linux_wait. */
4910 async_file_mark ();
4911 }
4912 else
4913 {
4914 delete_file_handler (linux_event_pipe[0]);
4915
4916 close (linux_event_pipe[0]);
4917 close (linux_event_pipe[1]);
4918 linux_event_pipe[0] = -1;
4919 linux_event_pipe[1] = -1;
4920 }
4921
4922 sigprocmask (SIG_UNBLOCK, &mask, NULL);
4923 }
4924
4925 return previous;
4926}
4927
4928static int
4929linux_start_non_stop (int nonstop)
4930{
4931 /* Register or unregister from event-loop accordingly. */
4932 linux_async (nonstop);
4933 return 0;
4934}
4935
cf8fd78b
PA
4936static int
4937linux_supports_multi_process (void)
4938{
4939 return 1;
4940}
4941
03583c20
UW
4942static int
4943linux_supports_disable_randomization (void)
4944{
4945#ifdef HAVE_PERSONALITY
4946 return 1;
4947#else
4948 return 0;
4949#endif
4950}
efcbbd14 4951
d1feda86
YQ
4952static int
4953linux_supports_agent (void)
4954{
4955 return 1;
4956}
4957
c2d6af84
PA
4958static int
4959linux_supports_range_stepping (void)
4960{
4961 if (*the_low_target.supports_range_stepping == NULL)
4962 return 0;
4963
4964 return (*the_low_target.supports_range_stepping) ();
4965}
4966
efcbbd14
UW
4967/* Enumerate spufs IDs for process PID. */
4968static int
4969spu_enumerate_spu_ids (long pid, unsigned char *buf, CORE_ADDR offset, int len)
4970{
4971 int pos = 0;
4972 int written = 0;
4973 char path[128];
4974 DIR *dir;
4975 struct dirent *entry;
4976
4977 sprintf (path, "/proc/%ld/fd", pid);
4978 dir = opendir (path);
4979 if (!dir)
4980 return -1;
4981
4982 rewinddir (dir);
4983 while ((entry = readdir (dir)) != NULL)
4984 {
4985 struct stat st;
4986 struct statfs stfs;
4987 int fd;
4988
4989 fd = atoi (entry->d_name);
4990 if (!fd)
4991 continue;
4992
4993 sprintf (path, "/proc/%ld/fd/%d", pid, fd);
4994 if (stat (path, &st) != 0)
4995 continue;
4996 if (!S_ISDIR (st.st_mode))
4997 continue;
4998
4999 if (statfs (path, &stfs) != 0)
5000 continue;
5001 if (stfs.f_type != SPUFS_MAGIC)
5002 continue;
5003
5004 if (pos >= offset && pos + 4 <= offset + len)
5005 {
5006 *(unsigned int *)(buf + pos - offset) = fd;
5007 written += 4;
5008 }
5009 pos += 4;
5010 }
5011
5012 closedir (dir);
5013 return written;
5014}
5015
5016/* Implements the to_xfer_partial interface for the TARGET_OBJECT_SPU
5017 object type, using the /proc file system. */
5018static int
5019linux_qxfer_spu (const char *annex, unsigned char *readbuf,
5020 unsigned const char *writebuf,
5021 CORE_ADDR offset, int len)
5022{
5023 long pid = lwpid_of (get_thread_lwp (current_inferior));
5024 char buf[128];
5025 int fd = 0;
5026 int ret = 0;
5027
5028 if (!writebuf && !readbuf)
5029 return -1;
5030
5031 if (!*annex)
5032 {
5033 if (!readbuf)
5034 return -1;
5035 else
5036 return spu_enumerate_spu_ids (pid, readbuf, offset, len);
5037 }
5038
5039 sprintf (buf, "/proc/%ld/fd/%s", pid, annex);
5040 fd = open (buf, writebuf? O_WRONLY : O_RDONLY);
5041 if (fd <= 0)
5042 return -1;
5043
5044 if (offset != 0
5045 && lseek (fd, (off_t) offset, SEEK_SET) != (off_t) offset)
5046 {
5047 close (fd);
5048 return 0;
5049 }
5050
5051 if (writebuf)
5052 ret = write (fd, writebuf, (size_t) len);
5053 else
5054 ret = read (fd, readbuf, (size_t) len);
5055
5056 close (fd);
5057 return ret;
5058}
5059
723b724b 5060#if defined PT_GETDSBT || defined PTRACE_GETFDPIC
78d85199
YQ
5061struct target_loadseg
5062{
5063 /* Core address to which the segment is mapped. */
5064 Elf32_Addr addr;
5065 /* VMA recorded in the program header. */
5066 Elf32_Addr p_vaddr;
5067 /* Size of this segment in memory. */
5068 Elf32_Word p_memsz;
5069};
5070
723b724b 5071# if defined PT_GETDSBT
78d85199
YQ
5072struct target_loadmap
5073{
5074 /* Protocol version number, must be zero. */
5075 Elf32_Word version;
5076 /* Pointer to the DSBT table, its size, and the DSBT index. */
5077 unsigned *dsbt_table;
5078 unsigned dsbt_size, dsbt_index;
5079 /* Number of segments in this map. */
5080 Elf32_Word nsegs;
5081 /* The actual memory map. */
5082 struct target_loadseg segs[/*nsegs*/];
5083};
723b724b
MF
5084# define LINUX_LOADMAP PT_GETDSBT
5085# define LINUX_LOADMAP_EXEC PTRACE_GETDSBT_EXEC
5086# define LINUX_LOADMAP_INTERP PTRACE_GETDSBT_INTERP
5087# else
5088struct target_loadmap
5089{
5090 /* Protocol version number, must be zero. */
5091 Elf32_Half version;
5092 /* Number of segments in this map. */
5093 Elf32_Half nsegs;
5094 /* The actual memory map. */
5095 struct target_loadseg segs[/*nsegs*/];
5096};
5097# define LINUX_LOADMAP PTRACE_GETFDPIC
5098# define LINUX_LOADMAP_EXEC PTRACE_GETFDPIC_EXEC
5099# define LINUX_LOADMAP_INTERP PTRACE_GETFDPIC_INTERP
5100# endif
78d85199 5101
78d85199
YQ
5102static int
5103linux_read_loadmap (const char *annex, CORE_ADDR offset,
5104 unsigned char *myaddr, unsigned int len)
5105{
5106 int pid = lwpid_of (get_thread_lwp (current_inferior));
5107 int addr = -1;
5108 struct target_loadmap *data = NULL;
5109 unsigned int actual_length, copy_length;
5110
5111 if (strcmp (annex, "exec") == 0)
723b724b 5112 addr = (int) LINUX_LOADMAP_EXEC;
78d85199 5113 else if (strcmp (annex, "interp") == 0)
723b724b 5114 addr = (int) LINUX_LOADMAP_INTERP;
78d85199
YQ
5115 else
5116 return -1;
5117
723b724b 5118 if (ptrace (LINUX_LOADMAP, pid, addr, &data) != 0)
78d85199
YQ
5119 return -1;
5120
5121 if (data == NULL)
5122 return -1;
5123
5124 actual_length = sizeof (struct target_loadmap)
5125 + sizeof (struct target_loadseg) * data->nsegs;
5126
5127 if (offset < 0 || offset > actual_length)
5128 return -1;
5129
5130 copy_length = actual_length - offset < len ? actual_length - offset : len;
5131 memcpy (myaddr, (char *) data + offset, copy_length);
5132 return copy_length;
5133}
723b724b
MF
5134#else
5135# define linux_read_loadmap NULL
5136#endif /* defined PT_GETDSBT || defined PTRACE_GETFDPIC */
78d85199 5137
1570b33e
L
5138static void
5139linux_process_qsupported (const char *query)
5140{
5141 if (the_low_target.process_qsupported != NULL)
5142 the_low_target.process_qsupported (query);
5143}
5144
219f2f23
PA
5145static int
5146linux_supports_tracepoints (void)
5147{
5148 if (*the_low_target.supports_tracepoints == NULL)
5149 return 0;
5150
5151 return (*the_low_target.supports_tracepoints) ();
5152}
5153
5154static CORE_ADDR
5155linux_read_pc (struct regcache *regcache)
5156{
5157 if (the_low_target.get_pc == NULL)
5158 return 0;
5159
5160 return (*the_low_target.get_pc) (regcache);
5161}
5162
5163static void
5164linux_write_pc (struct regcache *regcache, CORE_ADDR pc)
5165{
5166 gdb_assert (the_low_target.set_pc != NULL);
5167
5168 (*the_low_target.set_pc) (regcache, pc);
5169}
5170
8336d594
PA
5171static int
5172linux_thread_stopped (struct thread_info *thread)
5173{
5174 return get_thread_lwp (thread)->stopped;
5175}
5176
5177/* This exposes stop-all-threads functionality to other modules. */
5178
5179static void
7984d532 5180linux_pause_all (int freeze)
8336d594 5181{
7984d532
PA
5182 stop_all_lwps (freeze, NULL);
5183}
5184
5185/* This exposes unstop-all-threads functionality to other gdbserver
5186 modules. */
5187
5188static void
5189linux_unpause_all (int unfreeze)
5190{
5191 unstop_all_lwps (unfreeze, NULL);
8336d594
PA
5192}
5193
90d74c30
PA
5194static int
5195linux_prepare_to_access_memory (void)
5196{
5197 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
5198 running LWP. */
5199 if (non_stop)
5200 linux_pause_all (1);
5201 return 0;
5202}
5203
5204static void
0146f85b 5205linux_done_accessing_memory (void)
90d74c30
PA
5206{
5207 /* Neither ptrace nor /proc/PID/mem allow accessing memory through a
5208 running LWP. */
5209 if (non_stop)
5210 linux_unpause_all (1);
5211}
5212
fa593d66
PA
5213static int
5214linux_install_fast_tracepoint_jump_pad (CORE_ADDR tpoint, CORE_ADDR tpaddr,
5215 CORE_ADDR collector,
5216 CORE_ADDR lockaddr,
5217 ULONGEST orig_size,
5218 CORE_ADDR *jump_entry,
405f8e94
SS
5219 CORE_ADDR *trampoline,
5220 ULONGEST *trampoline_size,
fa593d66
PA
5221 unsigned char *jjump_pad_insn,
5222 ULONGEST *jjump_pad_insn_size,
5223 CORE_ADDR *adjusted_insn_addr,
405f8e94
SS
5224 CORE_ADDR *adjusted_insn_addr_end,
5225 char *err)
fa593d66
PA
5226{
5227 return (*the_low_target.install_fast_tracepoint_jump_pad)
5228 (tpoint, tpaddr, collector, lockaddr, orig_size,
405f8e94
SS
5229 jump_entry, trampoline, trampoline_size,
5230 jjump_pad_insn, jjump_pad_insn_size,
5231 adjusted_insn_addr, adjusted_insn_addr_end,
5232 err);
fa593d66
PA
5233}
5234
6a271cae
PA
5235static struct emit_ops *
5236linux_emit_ops (void)
5237{
5238 if (the_low_target.emit_ops != NULL)
5239 return (*the_low_target.emit_ops) ();
5240 else
5241 return NULL;
5242}
5243
405f8e94
SS
5244static int
5245linux_get_min_fast_tracepoint_insn_len (void)
5246{
5247 return (*the_low_target.get_min_fast_tracepoint_insn_len) ();
5248}
5249
2268b414
JK
5250/* Extract &phdr and num_phdr in the inferior. Return 0 on success. */
5251
5252static int
5253get_phdr_phnum_from_proc_auxv (const int pid, const int is_elf64,
5254 CORE_ADDR *phdr_memaddr, int *num_phdr)
5255{
5256 char filename[PATH_MAX];
5257 int fd;
5258 const int auxv_size = is_elf64
5259 ? sizeof (Elf64_auxv_t) : sizeof (Elf32_auxv_t);
5260 char buf[sizeof (Elf64_auxv_t)]; /* The larger of the two. */
5261
5262 xsnprintf (filename, sizeof filename, "/proc/%d/auxv", pid);
5263
5264 fd = open (filename, O_RDONLY);
5265 if (fd < 0)
5266 return 1;
5267
5268 *phdr_memaddr = 0;
5269 *num_phdr = 0;
5270 while (read (fd, buf, auxv_size) == auxv_size
5271 && (*phdr_memaddr == 0 || *num_phdr == 0))
5272 {
5273 if (is_elf64)
5274 {
5275 Elf64_auxv_t *const aux = (Elf64_auxv_t *) buf;
5276
5277 switch (aux->a_type)
5278 {
5279 case AT_PHDR:
5280 *phdr_memaddr = aux->a_un.a_val;
5281 break;
5282 case AT_PHNUM:
5283 *num_phdr = aux->a_un.a_val;
5284 break;
5285 }
5286 }
5287 else
5288 {
5289 Elf32_auxv_t *const aux = (Elf32_auxv_t *) buf;
5290
5291 switch (aux->a_type)
5292 {
5293 case AT_PHDR:
5294 *phdr_memaddr = aux->a_un.a_val;
5295 break;
5296 case AT_PHNUM:
5297 *num_phdr = aux->a_un.a_val;
5298 break;
5299 }
5300 }
5301 }
5302
5303 close (fd);
5304
5305 if (*phdr_memaddr == 0 || *num_phdr == 0)
5306 {
5307 warning ("Unexpected missing AT_PHDR and/or AT_PHNUM: "
5308 "phdr_memaddr = %ld, phdr_num = %d",
5309 (long) *phdr_memaddr, *num_phdr);
5310 return 2;
5311 }
5312
5313 return 0;
5314}
5315
5316/* Return &_DYNAMIC (via PT_DYNAMIC) in the inferior, or 0 if not present. */
5317
5318static CORE_ADDR
5319get_dynamic (const int pid, const int is_elf64)
5320{
5321 CORE_ADDR phdr_memaddr, relocation;
5322 int num_phdr, i;
5323 unsigned char *phdr_buf;
5324 const int phdr_size = is_elf64 ? sizeof (Elf64_Phdr) : sizeof (Elf32_Phdr);
5325
5326 if (get_phdr_phnum_from_proc_auxv (pid, is_elf64, &phdr_memaddr, &num_phdr))
5327 return 0;
5328
5329 gdb_assert (num_phdr < 100); /* Basic sanity check. */
5330 phdr_buf = alloca (num_phdr * phdr_size);
5331
5332 if (linux_read_memory (phdr_memaddr, phdr_buf, num_phdr * phdr_size))
5333 return 0;
5334
5335 /* Compute relocation: it is expected to be 0 for "regular" executables,
5336 non-zero for PIE ones. */
5337 relocation = -1;
5338 for (i = 0; relocation == -1 && i < num_phdr; i++)
5339 if (is_elf64)
5340 {
5341 Elf64_Phdr *const p = (Elf64_Phdr *) (phdr_buf + i * phdr_size);
5342
5343 if (p->p_type == PT_PHDR)
5344 relocation = phdr_memaddr - p->p_vaddr;
5345 }
5346 else
5347 {
5348 Elf32_Phdr *const p = (Elf32_Phdr *) (phdr_buf + i * phdr_size);
5349
5350 if (p->p_type == PT_PHDR)
5351 relocation = phdr_memaddr - p->p_vaddr;
5352 }
5353
5354 if (relocation == -1)
5355 {
e237a7e2
JK
5356 /* PT_PHDR is optional, but necessary for PIE in general. Fortunately
5357 any real world executables, including PIE executables, have always
5358 PT_PHDR present. PT_PHDR is not present in some shared libraries or
5359 in fpc (Free Pascal 2.4) binaries but neither of those have a need for
5360 or present DT_DEBUG anyway (fpc binaries are statically linked).
5361
5362 Therefore if there exists DT_DEBUG there is always also PT_PHDR.
5363
5364 GDB could find RELOCATION also from AT_ENTRY - e_entry. */
5365
2268b414
JK
5366 return 0;
5367 }
5368
5369 for (i = 0; i < num_phdr; i++)
5370 {
5371 if (is_elf64)
5372 {
5373 Elf64_Phdr *const p = (Elf64_Phdr *) (phdr_buf + i * phdr_size);
5374
5375 if (p->p_type == PT_DYNAMIC)
5376 return p->p_vaddr + relocation;
5377 }
5378 else
5379 {
5380 Elf32_Phdr *const p = (Elf32_Phdr *) (phdr_buf + i * phdr_size);
5381
5382 if (p->p_type == PT_DYNAMIC)
5383 return p->p_vaddr + relocation;
5384 }
5385 }
5386
5387 return 0;
5388}
5389
5390/* Return &_r_debug in the inferior, or -1 if not present. Return value
367ba2c2
MR
5391 can be 0 if the inferior does not yet have the library list initialized.
5392 We look for DT_MIPS_RLD_MAP first. MIPS executables use this instead of
5393 DT_DEBUG, although they sometimes contain an unused DT_DEBUG entry too. */
2268b414
JK
5394
5395static CORE_ADDR
5396get_r_debug (const int pid, const int is_elf64)
5397{
5398 CORE_ADDR dynamic_memaddr;
5399 const int dyn_size = is_elf64 ? sizeof (Elf64_Dyn) : sizeof (Elf32_Dyn);
5400 unsigned char buf[sizeof (Elf64_Dyn)]; /* The larger of the two. */
367ba2c2 5401 CORE_ADDR map = -1;
2268b414
JK
5402
5403 dynamic_memaddr = get_dynamic (pid, is_elf64);
5404 if (dynamic_memaddr == 0)
367ba2c2 5405 return map;
2268b414
JK
5406
5407 while (linux_read_memory (dynamic_memaddr, buf, dyn_size) == 0)
5408 {
5409 if (is_elf64)
5410 {
5411 Elf64_Dyn *const dyn = (Elf64_Dyn *) buf;
75f62ce7 5412#ifdef DT_MIPS_RLD_MAP
367ba2c2
MR
5413 union
5414 {
5415 Elf64_Xword map;
5416 unsigned char buf[sizeof (Elf64_Xword)];
5417 }
5418 rld_map;
5419
5420 if (dyn->d_tag == DT_MIPS_RLD_MAP)
5421 {
5422 if (linux_read_memory (dyn->d_un.d_val,
5423 rld_map.buf, sizeof (rld_map.buf)) == 0)
5424 return rld_map.map;
5425 else
5426 break;
5427 }
75f62ce7 5428#endif /* DT_MIPS_RLD_MAP */
2268b414 5429
367ba2c2
MR
5430 if (dyn->d_tag == DT_DEBUG && map == -1)
5431 map = dyn->d_un.d_val;
2268b414
JK
5432
5433 if (dyn->d_tag == DT_NULL)
5434 break;
5435 }
5436 else
5437 {
5438 Elf32_Dyn *const dyn = (Elf32_Dyn *) buf;
75f62ce7 5439#ifdef DT_MIPS_RLD_MAP
367ba2c2
MR
5440 union
5441 {
5442 Elf32_Word map;
5443 unsigned char buf[sizeof (Elf32_Word)];
5444 }
5445 rld_map;
5446
5447 if (dyn->d_tag == DT_MIPS_RLD_MAP)
5448 {
5449 if (linux_read_memory (dyn->d_un.d_val,
5450 rld_map.buf, sizeof (rld_map.buf)) == 0)
5451 return rld_map.map;
5452 else
5453 break;
5454 }
75f62ce7 5455#endif /* DT_MIPS_RLD_MAP */
2268b414 5456
367ba2c2
MR
5457 if (dyn->d_tag == DT_DEBUG && map == -1)
5458 map = dyn->d_un.d_val;
2268b414
JK
5459
5460 if (dyn->d_tag == DT_NULL)
5461 break;
5462 }
5463
5464 dynamic_memaddr += dyn_size;
5465 }
5466
367ba2c2 5467 return map;
2268b414
JK
5468}
5469
5470/* Read one pointer from MEMADDR in the inferior. */
5471
5472static int
5473read_one_ptr (CORE_ADDR memaddr, CORE_ADDR *ptr, int ptr_size)
5474{
485f1ee4
PA
5475 int ret;
5476
5477 /* Go through a union so this works on either big or little endian
5478 hosts, when the inferior's pointer size is smaller than the size
5479 of CORE_ADDR. It is assumed the inferior's endianness is the
5480 same of the superior's. */
5481 union
5482 {
5483 CORE_ADDR core_addr;
5484 unsigned int ui;
5485 unsigned char uc;
5486 } addr;
5487
5488 ret = linux_read_memory (memaddr, &addr.uc, ptr_size);
5489 if (ret == 0)
5490 {
5491 if (ptr_size == sizeof (CORE_ADDR))
5492 *ptr = addr.core_addr;
5493 else if (ptr_size == sizeof (unsigned int))
5494 *ptr = addr.ui;
5495 else
5496 gdb_assert_not_reached ("unhandled pointer size");
5497 }
5498 return ret;
2268b414
JK
5499}
5500
5501struct link_map_offsets
5502 {
5503 /* Offset and size of r_debug.r_version. */
5504 int r_version_offset;
5505
5506 /* Offset and size of r_debug.r_map. */
5507 int r_map_offset;
5508
5509 /* Offset to l_addr field in struct link_map. */
5510 int l_addr_offset;
5511
5512 /* Offset to l_name field in struct link_map. */
5513 int l_name_offset;
5514
5515 /* Offset to l_ld field in struct link_map. */
5516 int l_ld_offset;
5517
5518 /* Offset to l_next field in struct link_map. */
5519 int l_next_offset;
5520
5521 /* Offset to l_prev field in struct link_map. */
5522 int l_prev_offset;
5523 };
5524
fb723180 5525/* Construct qXfer:libraries-svr4:read reply. */
2268b414
JK
5526
5527static int
5528linux_qxfer_libraries_svr4 (const char *annex, unsigned char *readbuf,
5529 unsigned const char *writebuf,
5530 CORE_ADDR offset, int len)
5531{
5532 char *document;
5533 unsigned document_len;
5534 struct process_info_private *const priv = current_process ()->private;
5535 char filename[PATH_MAX];
5536 int pid, is_elf64;
5537
5538 static const struct link_map_offsets lmo_32bit_offsets =
5539 {
5540 0, /* r_version offset. */
5541 4, /* r_debug.r_map offset. */
5542 0, /* l_addr offset in link_map. */
5543 4, /* l_name offset in link_map. */
5544 8, /* l_ld offset in link_map. */
5545 12, /* l_next offset in link_map. */
5546 16 /* l_prev offset in link_map. */
5547 };
5548
5549 static const struct link_map_offsets lmo_64bit_offsets =
5550 {
5551 0, /* r_version offset. */
5552 8, /* r_debug.r_map offset. */
5553 0, /* l_addr offset in link_map. */
5554 8, /* l_name offset in link_map. */
5555 16, /* l_ld offset in link_map. */
5556 24, /* l_next offset in link_map. */
5557 32 /* l_prev offset in link_map. */
5558 };
5559 const struct link_map_offsets *lmo;
214d508e 5560 unsigned int machine;
b1fbec62
GB
5561 int ptr_size;
5562 CORE_ADDR lm_addr = 0, lm_prev = 0;
5563 int allocated = 1024;
5564 char *p;
5565 CORE_ADDR l_name, l_addr, l_ld, l_next, l_prev;
5566 int header_done = 0;
2268b414
JK
5567
5568 if (writebuf != NULL)
5569 return -2;
5570 if (readbuf == NULL)
5571 return -1;
5572
5573 pid = lwpid_of (get_thread_lwp (current_inferior));
5574 xsnprintf (filename, sizeof filename, "/proc/%d/exe", pid);
214d508e 5575 is_elf64 = elf_64_file_p (filename, &machine);
2268b414 5576 lmo = is_elf64 ? &lmo_64bit_offsets : &lmo_32bit_offsets;
b1fbec62 5577 ptr_size = is_elf64 ? 8 : 4;
2268b414 5578
b1fbec62
GB
5579 while (annex[0] != '\0')
5580 {
5581 const char *sep;
5582 CORE_ADDR *addrp;
5583 int len;
2268b414 5584
b1fbec62
GB
5585 sep = strchr (annex, '=');
5586 if (sep == NULL)
5587 break;
0c5bf5a9 5588
b1fbec62
GB
5589 len = sep - annex;
5590 if (len == 5 && strncmp (annex, "start", 5) == 0)
5591 addrp = &lm_addr;
5592 else if (len == 4 && strncmp (annex, "prev", 4) == 0)
5593 addrp = &lm_prev;
5594 else
5595 {
5596 annex = strchr (sep, ';');
5597 if (annex == NULL)
5598 break;
5599 annex++;
5600 continue;
5601 }
5602
5603 annex = decode_address_to_semicolon (addrp, sep + 1);
2268b414 5604 }
b1fbec62
GB
5605
5606 if (lm_addr == 0)
2268b414 5607 {
b1fbec62
GB
5608 int r_version = 0;
5609
5610 if (priv->r_debug == 0)
5611 priv->r_debug = get_r_debug (pid, is_elf64);
5612
5613 /* We failed to find DT_DEBUG. Such situation will not change
5614 for this inferior - do not retry it. Report it to GDB as
5615 E01, see for the reasons at the GDB solib-svr4.c side. */
5616 if (priv->r_debug == (CORE_ADDR) -1)
5617 return -1;
5618
5619 if (priv->r_debug != 0)
2268b414 5620 {
b1fbec62
GB
5621 if (linux_read_memory (priv->r_debug + lmo->r_version_offset,
5622 (unsigned char *) &r_version,
5623 sizeof (r_version)) != 0
5624 || r_version != 1)
5625 {
5626 warning ("unexpected r_debug version %d", r_version);
5627 }
5628 else if (read_one_ptr (priv->r_debug + lmo->r_map_offset,
5629 &lm_addr, ptr_size) != 0)
5630 {
5631 warning ("unable to read r_map from 0x%lx",
5632 (long) priv->r_debug + lmo->r_map_offset);
5633 }
2268b414 5634 }
b1fbec62 5635 }
2268b414 5636
b1fbec62
GB
5637 document = xmalloc (allocated);
5638 strcpy (document, "<library-list-svr4 version=\"1.0\"");
5639 p = document + strlen (document);
5640
5641 while (lm_addr
5642 && read_one_ptr (lm_addr + lmo->l_name_offset,
5643 &l_name, ptr_size) == 0
5644 && read_one_ptr (lm_addr + lmo->l_addr_offset,
5645 &l_addr, ptr_size) == 0
5646 && read_one_ptr (lm_addr + lmo->l_ld_offset,
5647 &l_ld, ptr_size) == 0
5648 && read_one_ptr (lm_addr + lmo->l_prev_offset,
5649 &l_prev, ptr_size) == 0
5650 && read_one_ptr (lm_addr + lmo->l_next_offset,
5651 &l_next, ptr_size) == 0)
5652 {
5653 unsigned char libname[PATH_MAX];
5654
5655 if (lm_prev != l_prev)
2268b414 5656 {
b1fbec62
GB
5657 warning ("Corrupted shared library list: 0x%lx != 0x%lx",
5658 (long) lm_prev, (long) l_prev);
5659 break;
2268b414
JK
5660 }
5661
d878444c
JK
5662 /* Ignore the first entry even if it has valid name as the first entry
5663 corresponds to the main executable. The first entry should not be
5664 skipped if the dynamic loader was loaded late by a static executable
5665 (see solib-svr4.c parameter ignore_first). But in such case the main
5666 executable does not have PT_DYNAMIC present and this function already
5667 exited above due to failed get_r_debug. */
5668 if (lm_prev == 0)
2268b414 5669 {
d878444c
JK
5670 sprintf (p, " main-lm=\"0x%lx\"", (unsigned long) lm_addr);
5671 p = p + strlen (p);
5672 }
5673 else
5674 {
5675 /* Not checking for error because reading may stop before
5676 we've got PATH_MAX worth of characters. */
5677 libname[0] = '\0';
5678 linux_read_memory (l_name, libname, sizeof (libname) - 1);
5679 libname[sizeof (libname) - 1] = '\0';
5680 if (libname[0] != '\0')
2268b414 5681 {
d878444c
JK
5682 /* 6x the size for xml_escape_text below. */
5683 size_t len = 6 * strlen ((char *) libname);
5684 char *name;
2268b414 5685
d878444c
JK
5686 if (!header_done)
5687 {
5688 /* Terminate `<library-list-svr4'. */
5689 *p++ = '>';
5690 header_done = 1;
5691 }
2268b414 5692
d878444c
JK
5693 while (allocated < p - document + len + 200)
5694 {
5695 /* Expand to guarantee sufficient storage. */
5696 uintptr_t document_len = p - document;
2268b414 5697
d878444c
JK
5698 document = xrealloc (document, 2 * allocated);
5699 allocated *= 2;
5700 p = document + document_len;
5701 }
5702
5703 name = xml_escape_text ((char *) libname);
5704 p += sprintf (p, "<library name=\"%s\" lm=\"0x%lx\" "
5705 "l_addr=\"0x%lx\" l_ld=\"0x%lx\"/>",
5706 name, (unsigned long) lm_addr,
5707 (unsigned long) l_addr, (unsigned long) l_ld);
5708 free (name);
5709 }
0afae3cf 5710 }
b1fbec62
GB
5711
5712 lm_prev = lm_addr;
5713 lm_addr = l_next;
2268b414
JK
5714 }
5715
b1fbec62
GB
5716 if (!header_done)
5717 {
5718 /* Empty list; terminate `<library-list-svr4'. */
5719 strcpy (p, "/>");
5720 }
5721 else
5722 strcpy (p, "</library-list-svr4>");
5723
2268b414
JK
5724 document_len = strlen (document);
5725 if (offset < document_len)
5726 document_len -= offset;
5727 else
5728 document_len = 0;
5729 if (len > document_len)
5730 len = document_len;
5731
5732 memcpy (readbuf, document + offset, len);
5733 xfree (document);
5734
5735 return len;
5736}
5737
9accd112
MM
5738#ifdef HAVE_LINUX_BTRACE
5739
969c39fb 5740/* See to_enable_btrace target method. */
9accd112
MM
5741
5742static struct btrace_target_info *
5743linux_low_enable_btrace (ptid_t ptid)
5744{
5745 struct btrace_target_info *tinfo;
5746
5747 tinfo = linux_enable_btrace (ptid);
3aee8918 5748
9accd112 5749 if (tinfo != NULL)
3aee8918
PA
5750 {
5751 struct thread_info *thread = find_thread_ptid (ptid);
5752 struct regcache *regcache = get_thread_regcache (thread, 0);
5753
5754 tinfo->ptr_bits = register_size (regcache->tdesc, 0) * 8;
5755 }
9accd112
MM
5756
5757 return tinfo;
5758}
5759
969c39fb 5760/* See to_disable_btrace target method. */
9accd112 5761
969c39fb
MM
5762static int
5763linux_low_disable_btrace (struct btrace_target_info *tinfo)
5764{
5765 enum btrace_error err;
5766
5767 err = linux_disable_btrace (tinfo);
5768 return (err == BTRACE_ERR_NONE ? 0 : -1);
5769}
5770
5771/* See to_read_btrace target method. */
5772
5773static int
9accd112
MM
5774linux_low_read_btrace (struct btrace_target_info *tinfo, struct buffer *buffer,
5775 int type)
5776{
5777 VEC (btrace_block_s) *btrace;
5778 struct btrace_block *block;
969c39fb 5779 enum btrace_error err;
9accd112
MM
5780 int i;
5781
969c39fb
MM
5782 btrace = NULL;
5783 err = linux_read_btrace (&btrace, tinfo, type);
5784 if (err != BTRACE_ERR_NONE)
5785 {
5786 if (err == BTRACE_ERR_OVERFLOW)
5787 buffer_grow_str0 (buffer, "E.Overflow.");
5788 else
5789 buffer_grow_str0 (buffer, "E.Generic Error.");
5790
5791 return -1;
5792 }
9accd112
MM
5793
5794 buffer_grow_str (buffer, "<!DOCTYPE btrace SYSTEM \"btrace.dtd\">\n");
5795 buffer_grow_str (buffer, "<btrace version=\"1.0\">\n");
5796
5797 for (i = 0; VEC_iterate (btrace_block_s, btrace, i, block); i++)
5798 buffer_xml_printf (buffer, "<block begin=\"0x%s\" end=\"0x%s\"/>\n",
5799 paddress (block->begin), paddress (block->end));
5800
969c39fb 5801 buffer_grow_str0 (buffer, "</btrace>\n");
9accd112
MM
5802
5803 VEC_free (btrace_block_s, btrace);
969c39fb
MM
5804
5805 return 0;
9accd112
MM
5806}
5807#endif /* HAVE_LINUX_BTRACE */
5808
ce3a066d
DJ
5809static struct target_ops linux_target_ops = {
5810 linux_create_inferior,
5811 linux_attach,
5812 linux_kill,
6ad8ae5c 5813 linux_detach,
8336d594 5814 linux_mourn,
444d6139 5815 linux_join,
ce3a066d
DJ
5816 linux_thread_alive,
5817 linux_resume,
5818 linux_wait,
5819 linux_fetch_registers,
5820 linux_store_registers,
90d74c30 5821 linux_prepare_to_access_memory,
0146f85b 5822 linux_done_accessing_memory,
ce3a066d
DJ
5823 linux_read_memory,
5824 linux_write_memory,
2f2893d9 5825 linux_look_up_symbols,
ef57601b 5826 linux_request_interrupt,
aa691b87 5827 linux_read_auxv,
d993e290
PA
5828 linux_insert_point,
5829 linux_remove_point,
e013ee27
OF
5830 linux_stopped_by_watchpoint,
5831 linux_stopped_data_address,
db0dfaa0
LM
5832#if defined(__UCLIBC__) && defined(HAS_NOMMU) \
5833 && defined(PT_TEXT_ADDR) && defined(PT_DATA_ADDR) \
5834 && defined(PT_TEXT_END_ADDR)
52fb6437 5835 linux_read_offsets,
dae5f5cf
DJ
5836#else
5837 NULL,
5838#endif
5839#ifdef USE_THREAD_DB
5840 thread_db_get_tls_address,
5841#else
5842 NULL,
52fb6437 5843#endif
efcbbd14 5844 linux_qxfer_spu,
59a016f0 5845 hostio_last_error_from_errno,
07e059b5 5846 linux_qxfer_osdata,
4aa995e1 5847 linux_xfer_siginfo,
bd99dc85
PA
5848 linux_supports_non_stop,
5849 linux_async,
5850 linux_start_non_stop,
cdbfd419
PP
5851 linux_supports_multi_process,
5852#ifdef USE_THREAD_DB
dc146f7c 5853 thread_db_handle_monitor_command,
cdbfd419 5854#else
dc146f7c 5855 NULL,
cdbfd419 5856#endif
d26e3629 5857 linux_common_core_of_thread,
78d85199 5858 linux_read_loadmap,
219f2f23
PA
5859 linux_process_qsupported,
5860 linux_supports_tracepoints,
5861 linux_read_pc,
8336d594
PA
5862 linux_write_pc,
5863 linux_thread_stopped,
7984d532 5864 NULL,
711e434b 5865 linux_pause_all,
7984d532 5866 linux_unpause_all,
fa593d66
PA
5867 linux_cancel_breakpoints,
5868 linux_stabilize_threads,
6a271cae 5869 linux_install_fast_tracepoint_jump_pad,
03583c20
UW
5870 linux_emit_ops,
5871 linux_supports_disable_randomization,
405f8e94 5872 linux_get_min_fast_tracepoint_insn_len,
2268b414 5873 linux_qxfer_libraries_svr4,
d1feda86 5874 linux_supports_agent,
9accd112
MM
5875#ifdef HAVE_LINUX_BTRACE
5876 linux_supports_btrace,
5877 linux_low_enable_btrace,
969c39fb 5878 linux_low_disable_btrace,
9accd112
MM
5879 linux_low_read_btrace,
5880#else
5881 NULL,
5882 NULL,
5883 NULL,
5884 NULL,
9accd112 5885#endif
c2d6af84 5886 linux_supports_range_stepping,
ce3a066d
DJ
5887};
5888
0d62e5e8
DJ
5889static void
5890linux_init_signals ()
5891{
5892 /* FIXME drow/2002-06-09: As above, we should check with LinuxThreads
5893 to find what the cancel signal actually is. */
1a981360 5894#ifndef __ANDROID__ /* Bionic doesn't use SIGRTMIN the way glibc does. */
254787d4 5895 signal (__SIGRTMIN+1, SIG_IGN);
60c3d7b0 5896#endif
0d62e5e8
DJ
5897}
5898
3aee8918
PA
5899#ifdef HAVE_LINUX_REGSETS
5900void
5901initialize_regsets_info (struct regsets_info *info)
5902{
5903 for (info->num_regsets = 0;
5904 info->regsets[info->num_regsets].size >= 0;
5905 info->num_regsets++)
5906 ;
3aee8918
PA
5907}
5908#endif
5909
da6d8c04
DJ
5910void
5911initialize_low (void)
5912{
bd99dc85
PA
5913 struct sigaction sigchld_action;
5914 memset (&sigchld_action, 0, sizeof (sigchld_action));
ce3a066d 5915 set_target_ops (&linux_target_ops);
611cb4a5
DJ
5916 set_breakpoint_data (the_low_target.breakpoint,
5917 the_low_target.breakpoint_len);
0d62e5e8 5918 linux_init_signals ();
aa7c7447 5919 linux_ptrace_init_warnings ();
bd99dc85
PA
5920
5921 sigchld_action.sa_handler = sigchld_handler;
5922 sigemptyset (&sigchld_action.sa_mask);
5923 sigchld_action.sa_flags = SA_RESTART;
5924 sigaction (SIGCHLD, &sigchld_action, NULL);
3aee8918
PA
5925
5926 initialize_low_arch ();
da6d8c04 5927}