Commit | Line | Data |
---|---|---|
3993f6b1 | 1 | /* GNU/Linux native-dependent code common to multiple platforms. |
dba24537 | 2 | |
42a4f53d | 3 | Copyright (C) 2001-2019 Free Software Foundation, Inc. |
3993f6b1 DJ |
4 | |
5 | This file is part of GDB. | |
6 | ||
7 | This program is free software; you can redistribute it and/or modify | |
8 | it under the terms of the GNU General Public License as published by | |
a9762ec7 | 9 | the Free Software Foundation; either version 3 of the License, or |
3993f6b1 DJ |
10 | (at your option) any later version. |
11 | ||
12 | This program is distributed in the hope that it will be useful, | |
13 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
15 | GNU General Public License for more details. | |
16 | ||
17 | You should have received a copy of the GNU General Public License | |
a9762ec7 | 18 | along with this program. If not, see <http://www.gnu.org/licenses/>. */ |
3993f6b1 DJ |
19 | |
20 | #include "defs.h" | |
21 | #include "inferior.h" | |
45741a9c | 22 | #include "infrun.h" |
3993f6b1 | 23 | #include "target.h" |
96d7229d LM |
24 | #include "nat/linux-nat.h" |
25 | #include "nat/linux-waitpid.h" | |
268a13a5 | 26 | #include "gdbsupport/gdb_wait.h" |
d6b0e80f AC |
27 | #include <unistd.h> |
28 | #include <sys/syscall.h> | |
5826e159 | 29 | #include "nat/gdb_ptrace.h" |
0274a8ce | 30 | #include "linux-nat.h" |
125f8a3d GB |
31 | #include "nat/linux-ptrace.h" |
32 | #include "nat/linux-procfs.h" | |
8cc73a39 | 33 | #include "nat/linux-personality.h" |
ac264b3b | 34 | #include "linux-fork.h" |
d6b0e80f AC |
35 | #include "gdbthread.h" |
36 | #include "gdbcmd.h" | |
37 | #include "regcache.h" | |
4f844a66 | 38 | #include "regset.h" |
dab06dbe | 39 | #include "inf-child.h" |
10d6c8cd DJ |
40 | #include "inf-ptrace.h" |
41 | #include "auxv.h" | |
1777feb0 | 42 | #include <sys/procfs.h> /* for elf_gregset etc. */ |
dba24537 AC |
43 | #include "elf-bfd.h" /* for elfcore_write_* */ |
44 | #include "gregset.h" /* for gregset */ | |
45 | #include "gdbcore.h" /* for get_exec_file */ | |
46 | #include <ctype.h> /* for isdigit */ | |
53ce3c39 | 47 | #include <sys/stat.h> /* for struct stat */ |
dba24537 | 48 | #include <fcntl.h> /* for O_RDONLY */ |
b84876c2 PA |
49 | #include "inf-loop.h" |
50 | #include "event-loop.h" | |
51 | #include "event-top.h" | |
07e059b5 VP |
52 | #include <pwd.h> |
53 | #include <sys/types.h> | |
2978b111 | 54 | #include <dirent.h> |
07e059b5 | 55 | #include "xml-support.h" |
efcbbd14 | 56 | #include <sys/vfs.h> |
6c95b8df | 57 | #include "solib.h" |
125f8a3d | 58 | #include "nat/linux-osdata.h" |
6432734d | 59 | #include "linux-tdep.h" |
7dcd53a0 | 60 | #include "symfile.h" |
268a13a5 | 61 | #include "gdbsupport/agent.h" |
5808517f | 62 | #include "tracepoint.h" |
268a13a5 | 63 | #include "gdbsupport/buffer.h" |
6ecd4729 | 64 | #include "target-descriptions.h" |
268a13a5 | 65 | #include "gdbsupport/filestuff.h" |
77e371c0 | 66 | #include "objfiles.h" |
7a6a1731 | 67 | #include "nat/linux-namespaces.h" |
268a13a5 TT |
68 | #include "gdbsupport/fileio.h" |
69 | #include "gdbsupport/scope-exit.h" | |
efcbbd14 | 70 | |
1777feb0 | 71 | /* This comment documents high-level logic of this file. |
8a77dff3 VP |
72 | |
73 | Waiting for events in sync mode | |
74 | =============================== | |
75 | ||
4a6ed09b PA |
76 | When waiting for an event in a specific thread, we just use waitpid, |
77 | passing the specific pid, and not passing WNOHANG. | |
78 | ||
79 | When waiting for an event in all threads, waitpid is not quite good: | |
80 | ||
81 | - If the thread group leader exits while other threads in the thread | |
82 | group still exist, waitpid(TGID, ...) hangs. That waitpid won't | |
83 | return an exit status until the other threads in the group are | |
84 | reaped. | |
85 | ||
86 | - When a non-leader thread execs, that thread just vanishes without | |
87 | reporting an exit (so we'd hang if we waited for it explicitly in | |
88 | that case). The exec event is instead reported to the TGID pid. | |
89 | ||
90 | The solution is to always use -1 and WNOHANG, together with | |
91 | sigsuspend. | |
92 | ||
93 | First, we use non-blocking waitpid to check for events. If nothing is | |
94 | found, we use sigsuspend to wait for SIGCHLD. When SIGCHLD arrives, | |
95 | it means something happened to a child process. As soon as we know | |
96 | there's an event, we get back to calling nonblocking waitpid. | |
97 | ||
98 | Note that SIGCHLD should be blocked between waitpid and sigsuspend | |
99 | calls, so that we don't miss a signal. If SIGCHLD arrives in between, | |
100 | when it's blocked, the signal becomes pending and sigsuspend | |
101 | immediately notices it and returns. | |
102 | ||
103 | Waiting for events in async mode (TARGET_WNOHANG) | |
104 | ================================================= | |
8a77dff3 | 105 | |
7feb7d06 PA |
106 | In async mode, GDB should always be ready to handle both user input |
107 | and target events, so neither blocking waitpid nor sigsuspend are | |
108 | viable options. Instead, we should asynchronously notify the GDB main | |
109 | event loop whenever there's an unprocessed event from the target. We | |
110 | detect asynchronous target events by handling SIGCHLD signals. To | |
111 | notify the event loop about target events, the self-pipe trick is used | |
112 | --- a pipe is registered as waitable event source in the event loop, | |
113 | the event loop select/poll's on the read end of this pipe (as well on | |
114 | other event sources, e.g., stdin), and the SIGCHLD handler writes a | |
115 | byte to this pipe. This is more portable than relying on | |
116 | pselect/ppoll, since on kernels that lack those syscalls, libc | |
117 | emulates them with select/poll+sigprocmask, and that is racy | |
118 | (a.k.a. plain broken). | |
119 | ||
120 | Obviously, if we fail to notify the event loop if there's a target | |
121 | event, it's bad. OTOH, if we notify the event loop when there's no | |
122 | event from the target, linux_nat_wait will detect that there's no real | |
123 | event to report, and return event of type TARGET_WAITKIND_IGNORE. | |
124 | This is mostly harmless, but it will waste time and is better avoided. | |
125 | ||
126 | The main design point is that every time GDB is outside linux-nat.c, | |
127 | we have a SIGCHLD handler installed that is called when something | |
128 | happens to the target and notifies the GDB event loop. Whenever GDB | |
129 | core decides to handle the event, and calls into linux-nat.c, we | |
130 | process things as in sync mode, except that the we never block in | |
131 | sigsuspend. | |
132 | ||
133 | While processing an event, we may end up momentarily blocked in | |
134 | waitpid calls. Those waitpid calls, while blocking, are guarantied to | |
135 | return quickly. E.g., in all-stop mode, before reporting to the core | |
136 | that an LWP hit a breakpoint, all LWPs are stopped by sending them | |
137 | SIGSTOP, and synchronously waiting for the SIGSTOP to be reported. | |
138 | Note that this is different from blocking indefinitely waiting for the | |
139 | next event --- here, we're already handling an event. | |
8a77dff3 VP |
140 | |
141 | Use of signals | |
142 | ============== | |
143 | ||
144 | We stop threads by sending a SIGSTOP. The use of SIGSTOP instead of another | |
145 | signal is not entirely significant; we just need for a signal to be delivered, | |
146 | so that we can intercept it. SIGSTOP's advantage is that it can not be | |
147 | blocked. A disadvantage is that it is not a real-time signal, so it can only | |
148 | be queued once; we do not keep track of other sources of SIGSTOP. | |
149 | ||
150 | Two other signals that can't be blocked are SIGCONT and SIGKILL. But we can't | |
151 | use them, because they have special behavior when the signal is generated - | |
152 | not when it is delivered. SIGCONT resumes the entire thread group and SIGKILL | |
153 | kills the entire thread group. | |
154 | ||
155 | A delivered SIGSTOP would stop the entire thread group, not just the thread we | |
156 | tkill'd. But we never let the SIGSTOP be delivered; we always intercept and | |
157 | cancel it (by PTRACE_CONT without passing SIGSTOP). | |
158 | ||
159 | We could use a real-time signal instead. This would solve those problems; we | |
160 | could use PTRACE_GETSIGINFO to locate the specific stop signals sent by GDB. | |
161 | But we would still have to have some support for SIGSTOP, since PTRACE_ATTACH | |
162 | generates it, and there are races with trying to find a signal that is not | |
4a6ed09b PA |
163 | blocked. |
164 | ||
165 | Exec events | |
166 | =========== | |
167 | ||
168 | The case of a thread group (process) with 3 or more threads, and a | |
169 | thread other than the leader execs is worth detailing: | |
170 | ||
171 | On an exec, the Linux kernel destroys all threads except the execing | |
172 | one in the thread group, and resets the execing thread's tid to the | |
173 | tgid. No exit notification is sent for the execing thread -- from the | |
174 | ptracer's perspective, it appears as though the execing thread just | |
175 | vanishes. Until we reap all other threads except the leader and the | |
176 | execing thread, the leader will be zombie, and the execing thread will | |
177 | be in `D (disc sleep)' state. As soon as all other threads are | |
178 | reaped, the execing thread changes its tid to the tgid, and the | |
179 | previous (zombie) leader vanishes, giving place to the "new" | |
180 | leader. */ | |
a0ef4274 | 181 | |
dba24537 AC |
182 | #ifndef O_LARGEFILE |
183 | #define O_LARGEFILE 0 | |
184 | #endif | |
0274a8ce | 185 | |
f6ac5f3d PA |
186 | struct linux_nat_target *linux_target; |
187 | ||
433bbbf8 | 188 | /* Does the current host support PTRACE_GETREGSET? */ |
0bdb2f78 | 189 | enum tribool have_ptrace_getregset = TRIBOOL_UNKNOWN; |
433bbbf8 | 190 | |
ccce17b0 | 191 | static unsigned int debug_linux_nat; |
920d2a44 AC |
192 | static void |
193 | show_debug_linux_nat (struct ui_file *file, int from_tty, | |
194 | struct cmd_list_element *c, const char *value) | |
195 | { | |
196 | fprintf_filtered (file, _("Debugging of GNU/Linux lwp module is %s.\n"), | |
197 | value); | |
198 | } | |
d6b0e80f | 199 | |
ae087d01 DJ |
200 | struct simple_pid_list |
201 | { | |
202 | int pid; | |
3d799a95 | 203 | int status; |
ae087d01 DJ |
204 | struct simple_pid_list *next; |
205 | }; | |
206 | struct simple_pid_list *stopped_pids; | |
207 | ||
aa01bd36 PA |
208 | /* Whether target_thread_events is in effect. */ |
209 | static int report_thread_events; | |
210 | ||
3dd5b83d PA |
211 | /* Async mode support. */ |
212 | ||
b84876c2 PA |
213 | /* The read/write ends of the pipe registered as waitable file in the |
214 | event loop. */ | |
215 | static int linux_nat_event_pipe[2] = { -1, -1 }; | |
216 | ||
198297aa PA |
217 | /* True if we're currently in async mode. */ |
218 | #define linux_is_async_p() (linux_nat_event_pipe[0] != -1) | |
219 | ||
7feb7d06 | 220 | /* Flush the event pipe. */ |
b84876c2 | 221 | |
7feb7d06 PA |
222 | static void |
223 | async_file_flush (void) | |
b84876c2 | 224 | { |
7feb7d06 PA |
225 | int ret; |
226 | char buf; | |
b84876c2 | 227 | |
7feb7d06 | 228 | do |
b84876c2 | 229 | { |
7feb7d06 | 230 | ret = read (linux_nat_event_pipe[0], &buf, 1); |
b84876c2 | 231 | } |
7feb7d06 | 232 | while (ret >= 0 || (ret == -1 && errno == EINTR)); |
b84876c2 PA |
233 | } |
234 | ||
7feb7d06 PA |
235 | /* Put something (anything, doesn't matter what, or how much) in event |
236 | pipe, so that the select/poll in the event-loop realizes we have | |
237 | something to process. */ | |
252fbfc8 | 238 | |
b84876c2 | 239 | static void |
7feb7d06 | 240 | async_file_mark (void) |
b84876c2 | 241 | { |
7feb7d06 | 242 | int ret; |
b84876c2 | 243 | |
7feb7d06 PA |
244 | /* It doesn't really matter what the pipe contains, as long we end |
245 | up with something in it. Might as well flush the previous | |
246 | left-overs. */ | |
247 | async_file_flush (); | |
b84876c2 | 248 | |
7feb7d06 | 249 | do |
b84876c2 | 250 | { |
7feb7d06 | 251 | ret = write (linux_nat_event_pipe[1], "+", 1); |
b84876c2 | 252 | } |
7feb7d06 | 253 | while (ret == -1 && errno == EINTR); |
b84876c2 | 254 | |
7feb7d06 PA |
255 | /* Ignore EAGAIN. If the pipe is full, the event loop will already |
256 | be awakened anyway. */ | |
b84876c2 PA |
257 | } |
258 | ||
7feb7d06 PA |
259 | static int kill_lwp (int lwpid, int signo); |
260 | ||
d3a70e03 | 261 | static int stop_callback (struct lwp_info *lp); |
7feb7d06 PA |
262 | |
263 | static void block_child_signals (sigset_t *prev_mask); | |
264 | static void restore_child_signals_mask (sigset_t *prev_mask); | |
2277426b PA |
265 | |
266 | struct lwp_info; | |
267 | static struct lwp_info *add_lwp (ptid_t ptid); | |
268 | static void purge_lwp_list (int pid); | |
4403d8e9 | 269 | static void delete_lwp (ptid_t ptid); |
2277426b PA |
270 | static struct lwp_info *find_lwp_pid (ptid_t ptid); |
271 | ||
8a99810d PA |
272 | static int lwp_status_pending_p (struct lwp_info *lp); |
273 | ||
e7ad2f14 PA |
274 | static void save_stop_reason (struct lwp_info *lp); |
275 | ||
cff068da GB |
276 | \f |
277 | /* LWP accessors. */ | |
278 | ||
279 | /* See nat/linux-nat.h. */ | |
280 | ||
281 | ptid_t | |
282 | ptid_of_lwp (struct lwp_info *lwp) | |
283 | { | |
284 | return lwp->ptid; | |
285 | } | |
286 | ||
287 | /* See nat/linux-nat.h. */ | |
288 | ||
4b134ca1 GB |
289 | void |
290 | lwp_set_arch_private_info (struct lwp_info *lwp, | |
291 | struct arch_lwp_info *info) | |
292 | { | |
293 | lwp->arch_private = info; | |
294 | } | |
295 | ||
296 | /* See nat/linux-nat.h. */ | |
297 | ||
298 | struct arch_lwp_info * | |
299 | lwp_arch_private_info (struct lwp_info *lwp) | |
300 | { | |
301 | return lwp->arch_private; | |
302 | } | |
303 | ||
304 | /* See nat/linux-nat.h. */ | |
305 | ||
cff068da GB |
306 | int |
307 | lwp_is_stopped (struct lwp_info *lwp) | |
308 | { | |
309 | return lwp->stopped; | |
310 | } | |
311 | ||
312 | /* See nat/linux-nat.h. */ | |
313 | ||
314 | enum target_stop_reason | |
315 | lwp_stop_reason (struct lwp_info *lwp) | |
316 | { | |
317 | return lwp->stop_reason; | |
318 | } | |
319 | ||
0e00e962 AA |
320 | /* See nat/linux-nat.h. */ |
321 | ||
322 | int | |
323 | lwp_is_stepping (struct lwp_info *lwp) | |
324 | { | |
325 | return lwp->step; | |
326 | } | |
327 | ||
ae087d01 DJ |
328 | \f |
329 | /* Trivial list manipulation functions to keep track of a list of | |
330 | new stopped processes. */ | |
331 | static void | |
3d799a95 | 332 | add_to_pid_list (struct simple_pid_list **listp, int pid, int status) |
ae087d01 | 333 | { |
8d749320 | 334 | struct simple_pid_list *new_pid = XNEW (struct simple_pid_list); |
e0881a8e | 335 | |
ae087d01 | 336 | new_pid->pid = pid; |
3d799a95 | 337 | new_pid->status = status; |
ae087d01 DJ |
338 | new_pid->next = *listp; |
339 | *listp = new_pid; | |
340 | } | |
341 | ||
342 | static int | |
46a96992 | 343 | pull_pid_from_list (struct simple_pid_list **listp, int pid, int *statusp) |
ae087d01 DJ |
344 | { |
345 | struct simple_pid_list **p; | |
346 | ||
347 | for (p = listp; *p != NULL; p = &(*p)->next) | |
348 | if ((*p)->pid == pid) | |
349 | { | |
350 | struct simple_pid_list *next = (*p)->next; | |
e0881a8e | 351 | |
46a96992 | 352 | *statusp = (*p)->status; |
ae087d01 DJ |
353 | xfree (*p); |
354 | *p = next; | |
355 | return 1; | |
356 | } | |
357 | return 0; | |
358 | } | |
359 | ||
de0d863e DB |
360 | /* Return the ptrace options that we want to try to enable. */ |
361 | ||
362 | static int | |
363 | linux_nat_ptrace_options (int attached) | |
364 | { | |
365 | int options = 0; | |
366 | ||
367 | if (!attached) | |
368 | options |= PTRACE_O_EXITKILL; | |
369 | ||
370 | options |= (PTRACE_O_TRACESYSGOOD | |
371 | | PTRACE_O_TRACEVFORKDONE | |
372 | | PTRACE_O_TRACEVFORK | |
373 | | PTRACE_O_TRACEFORK | |
374 | | PTRACE_O_TRACEEXEC); | |
375 | ||
376 | return options; | |
377 | } | |
378 | ||
1b919490 VB |
379 | /* Initialize ptrace and procfs warnings and check for supported |
380 | ptrace features given PID. | |
beed38b8 JB |
381 | |
382 | ATTACHED should be nonzero iff we attached to the inferior. */ | |
3993f6b1 DJ |
383 | |
384 | static void | |
1b919490 | 385 | linux_init_ptrace_procfs (pid_t pid, int attached) |
3993f6b1 | 386 | { |
de0d863e DB |
387 | int options = linux_nat_ptrace_options (attached); |
388 | ||
389 | linux_enable_event_reporting (pid, options); | |
96d7229d | 390 | linux_ptrace_init_warnings (); |
1b919490 | 391 | linux_proc_init_warnings (); |
4de4c07c DJ |
392 | } |
393 | ||
f6ac5f3d PA |
394 | linux_nat_target::~linux_nat_target () |
395 | {} | |
396 | ||
397 | void | |
398 | linux_nat_target::post_attach (int pid) | |
4de4c07c | 399 | { |
1b919490 | 400 | linux_init_ptrace_procfs (pid, 1); |
4de4c07c DJ |
401 | } |
402 | ||
f6ac5f3d PA |
403 | void |
404 | linux_nat_target::post_startup_inferior (ptid_t ptid) | |
4de4c07c | 405 | { |
1b919490 | 406 | linux_init_ptrace_procfs (ptid.pid (), 0); |
4de4c07c DJ |
407 | } |
408 | ||
4403d8e9 JK |
409 | /* Return the number of known LWPs in the tgid given by PID. */ |
410 | ||
411 | static int | |
412 | num_lwps (int pid) | |
413 | { | |
414 | int count = 0; | |
415 | struct lwp_info *lp; | |
416 | ||
417 | for (lp = lwp_list; lp; lp = lp->next) | |
e99b03dc | 418 | if (lp->ptid.pid () == pid) |
4403d8e9 JK |
419 | count++; |
420 | ||
421 | return count; | |
422 | } | |
423 | ||
169bb27b | 424 | /* Deleter for lwp_info unique_ptr specialisation. */ |
4403d8e9 | 425 | |
169bb27b | 426 | struct lwp_deleter |
4403d8e9 | 427 | { |
169bb27b AB |
428 | void operator() (struct lwp_info *lwp) const |
429 | { | |
430 | delete_lwp (lwp->ptid); | |
431 | } | |
432 | }; | |
4403d8e9 | 433 | |
169bb27b AB |
434 | /* A unique_ptr specialisation for lwp_info. */ |
435 | ||
436 | typedef std::unique_ptr<struct lwp_info, lwp_deleter> lwp_info_up; | |
4403d8e9 | 437 | |
d83ad864 DB |
438 | /* Target hook for follow_fork. On entry inferior_ptid must be the |
439 | ptid of the followed inferior. At return, inferior_ptid will be | |
440 | unchanged. */ | |
441 | ||
f6ac5f3d PA |
442 | int |
443 | linux_nat_target::follow_fork (int follow_child, int detach_fork) | |
3993f6b1 | 444 | { |
d83ad864 | 445 | if (!follow_child) |
4de4c07c | 446 | { |
6c95b8df | 447 | struct lwp_info *child_lp = NULL; |
d83ad864 | 448 | int has_vforked; |
79639e11 | 449 | ptid_t parent_ptid, child_ptid; |
d83ad864 DB |
450 | int parent_pid, child_pid; |
451 | ||
452 | has_vforked = (inferior_thread ()->pending_follow.kind | |
453 | == TARGET_WAITKIND_VFORKED); | |
79639e11 PA |
454 | parent_ptid = inferior_ptid; |
455 | child_ptid = inferior_thread ()->pending_follow.value.related_pid; | |
e38504b3 TT |
456 | parent_pid = parent_ptid.lwp (); |
457 | child_pid = child_ptid.lwp (); | |
4de4c07c | 458 | |
1777feb0 | 459 | /* We're already attached to the parent, by default. */ |
2989a365 | 460 | child_lp = add_lwp (child_ptid); |
d83ad864 DB |
461 | child_lp->stopped = 1; |
462 | child_lp->last_resume_kind = resume_stop; | |
4de4c07c | 463 | |
ac264b3b MS |
464 | /* Detach new forked process? */ |
465 | if (detach_fork) | |
f75c00e4 | 466 | { |
95347337 AB |
467 | int child_stop_signal = 0; |
468 | bool detach_child = true; | |
4403d8e9 | 469 | |
169bb27b AB |
470 | /* Move CHILD_LP into a unique_ptr and clear the source pointer |
471 | to prevent us doing anything stupid with it. */ | |
472 | lwp_info_up child_lp_ptr (child_lp); | |
473 | child_lp = nullptr; | |
474 | ||
475 | linux_target->low_prepare_to_resume (child_lp_ptr.get ()); | |
c077881a HZ |
476 | |
477 | /* When debugging an inferior in an architecture that supports | |
478 | hardware single stepping on a kernel without commit | |
479 | 6580807da14c423f0d0a708108e6df6ebc8bc83d, the vfork child | |
480 | process starts with the TIF_SINGLESTEP/X86_EFLAGS_TF bits | |
481 | set if the parent process had them set. | |
482 | To work around this, single step the child process | |
483 | once before detaching to clear the flags. */ | |
484 | ||
2fd9d7ca PA |
485 | /* Note that we consult the parent's architecture instead of |
486 | the child's because there's no inferior for the child at | |
487 | this point. */ | |
c077881a | 488 | if (!gdbarch_software_single_step_p (target_thread_architecture |
2fd9d7ca | 489 | (parent_ptid))) |
c077881a | 490 | { |
95347337 AB |
491 | int status; |
492 | ||
c077881a HZ |
493 | linux_disable_event_reporting (child_pid); |
494 | if (ptrace (PTRACE_SINGLESTEP, child_pid, 0, 0) < 0) | |
495 | perror_with_name (_("Couldn't do single step")); | |
496 | if (my_waitpid (child_pid, &status, 0) < 0) | |
497 | perror_with_name (_("Couldn't wait vfork process")); | |
95347337 AB |
498 | else |
499 | { | |
500 | detach_child = WIFSTOPPED (status); | |
501 | child_stop_signal = WSTOPSIG (status); | |
502 | } | |
c077881a HZ |
503 | } |
504 | ||
95347337 | 505 | if (detach_child) |
9caaaa83 | 506 | { |
95347337 | 507 | int signo = child_stop_signal; |
9caaaa83 | 508 | |
9caaaa83 PA |
509 | if (signo != 0 |
510 | && !signal_pass_state (gdb_signal_from_host (signo))) | |
511 | signo = 0; | |
512 | ptrace (PTRACE_DETACH, child_pid, 0, signo); | |
513 | } | |
ac264b3b MS |
514 | } |
515 | else | |
516 | { | |
2989a365 TT |
517 | scoped_restore save_inferior_ptid |
518 | = make_scoped_restore (&inferior_ptid); | |
519 | inferior_ptid = child_ptid; | |
520 | ||
6c95b8df | 521 | /* Let the thread_db layer learn about this new process. */ |
2277426b | 522 | check_for_thread_db (); |
ac264b3b | 523 | } |
9016a515 DJ |
524 | |
525 | if (has_vforked) | |
526 | { | |
3ced3da4 | 527 | struct lwp_info *parent_lp; |
6c95b8df | 528 | |
79639e11 | 529 | parent_lp = find_lwp_pid (parent_ptid); |
96d7229d | 530 | gdb_assert (linux_supports_tracefork () >= 0); |
3ced3da4 | 531 | |
96d7229d | 532 | if (linux_supports_tracevforkdone ()) |
9016a515 | 533 | { |
6c95b8df PA |
534 | if (debug_linux_nat) |
535 | fprintf_unfiltered (gdb_stdlog, | |
536 | "LCFF: waiting for VFORK_DONE on %d\n", | |
537 | parent_pid); | |
3ced3da4 | 538 | parent_lp->stopped = 1; |
9016a515 | 539 | |
6c95b8df PA |
540 | /* We'll handle the VFORK_DONE event like any other |
541 | event, in target_wait. */ | |
9016a515 DJ |
542 | } |
543 | else | |
544 | { | |
545 | /* We can't insert breakpoints until the child has | |
546 | finished with the shared memory region. We need to | |
547 | wait until that happens. Ideal would be to just | |
548 | call: | |
549 | - ptrace (PTRACE_SYSCALL, parent_pid, 0, 0); | |
550 | - waitpid (parent_pid, &status, __WALL); | |
551 | However, most architectures can't handle a syscall | |
552 | being traced on the way out if it wasn't traced on | |
553 | the way in. | |
554 | ||
555 | We might also think to loop, continuing the child | |
556 | until it exits or gets a SIGTRAP. One problem is | |
557 | that the child might call ptrace with PTRACE_TRACEME. | |
558 | ||
559 | There's no simple and reliable way to figure out when | |
560 | the vforked child will be done with its copy of the | |
561 | shared memory. We could step it out of the syscall, | |
562 | two instructions, let it go, and then single-step the | |
563 | parent once. When we have hardware single-step, this | |
564 | would work; with software single-step it could still | |
565 | be made to work but we'd have to be able to insert | |
566 | single-step breakpoints in the child, and we'd have | |
567 | to insert -just- the single-step breakpoint in the | |
568 | parent. Very awkward. | |
569 | ||
570 | In the end, the best we can do is to make sure it | |
571 | runs for a little while. Hopefully it will be out of | |
572 | range of any breakpoints we reinsert. Usually this | |
573 | is only the single-step breakpoint at vfork's return | |
574 | point. */ | |
575 | ||
6c95b8df PA |
576 | if (debug_linux_nat) |
577 | fprintf_unfiltered (gdb_stdlog, | |
3e43a32a MS |
578 | "LCFF: no VFORK_DONE " |
579 | "support, sleeping a bit\n"); | |
6c95b8df | 580 | |
9016a515 | 581 | usleep (10000); |
9016a515 | 582 | |
6c95b8df PA |
583 | /* Pretend we've seen a PTRACE_EVENT_VFORK_DONE event, |
584 | and leave it pending. The next linux_nat_resume call | |
585 | will notice a pending event, and bypasses actually | |
586 | resuming the inferior. */ | |
3ced3da4 PA |
587 | parent_lp->status = 0; |
588 | parent_lp->waitstatus.kind = TARGET_WAITKIND_VFORK_DONE; | |
589 | parent_lp->stopped = 1; | |
6c95b8df PA |
590 | |
591 | /* If we're in async mode, need to tell the event loop | |
592 | there's something here to process. */ | |
d9d41e78 | 593 | if (target_is_async_p ()) |
6c95b8df PA |
594 | async_file_mark (); |
595 | } | |
9016a515 | 596 | } |
4de4c07c | 597 | } |
3993f6b1 | 598 | else |
4de4c07c | 599 | { |
3ced3da4 | 600 | struct lwp_info *child_lp; |
4de4c07c | 601 | |
3ced3da4 PA |
602 | child_lp = add_lwp (inferior_ptid); |
603 | child_lp->stopped = 1; | |
25289eb2 | 604 | child_lp->last_resume_kind = resume_stop; |
6c95b8df | 605 | |
6c95b8df | 606 | /* Let the thread_db layer learn about this new process. */ |
ef29ce1a | 607 | check_for_thread_db (); |
4de4c07c DJ |
608 | } |
609 | ||
610 | return 0; | |
611 | } | |
612 | ||
4de4c07c | 613 | \f |
f6ac5f3d PA |
614 | int |
615 | linux_nat_target::insert_fork_catchpoint (int pid) | |
4de4c07c | 616 | { |
96d7229d | 617 | return !linux_supports_tracefork (); |
3993f6b1 DJ |
618 | } |
619 | ||
f6ac5f3d PA |
620 | int |
621 | linux_nat_target::remove_fork_catchpoint (int pid) | |
eb73ad13 PA |
622 | { |
623 | return 0; | |
624 | } | |
625 | ||
f6ac5f3d PA |
626 | int |
627 | linux_nat_target::insert_vfork_catchpoint (int pid) | |
3993f6b1 | 628 | { |
96d7229d | 629 | return !linux_supports_tracefork (); |
3993f6b1 DJ |
630 | } |
631 | ||
f6ac5f3d PA |
632 | int |
633 | linux_nat_target::remove_vfork_catchpoint (int pid) | |
eb73ad13 PA |
634 | { |
635 | return 0; | |
636 | } | |
637 | ||
f6ac5f3d PA |
638 | int |
639 | linux_nat_target::insert_exec_catchpoint (int pid) | |
3993f6b1 | 640 | { |
96d7229d | 641 | return !linux_supports_tracefork (); |
3993f6b1 DJ |
642 | } |
643 | ||
f6ac5f3d PA |
644 | int |
645 | linux_nat_target::remove_exec_catchpoint (int pid) | |
eb73ad13 PA |
646 | { |
647 | return 0; | |
648 | } | |
649 | ||
f6ac5f3d PA |
650 | int |
651 | linux_nat_target::set_syscall_catchpoint (int pid, bool needed, int any_count, | |
652 | gdb::array_view<const int> syscall_counts) | |
a96d9b2e | 653 | { |
96d7229d | 654 | if (!linux_supports_tracesysgood ()) |
77b06cd7 TJB |
655 | return 1; |
656 | ||
a96d9b2e SDJ |
657 | /* On GNU/Linux, we ignore the arguments. It means that we only |
658 | enable the syscall catchpoints, but do not disable them. | |
77b06cd7 | 659 | |
649a140c | 660 | Also, we do not use the `syscall_counts' information because we do not |
a96d9b2e SDJ |
661 | filter system calls here. We let GDB do the logic for us. */ |
662 | return 0; | |
663 | } | |
664 | ||
774113b0 PA |
665 | /* List of known LWPs, keyed by LWP PID. This speeds up the common |
666 | case of mapping a PID returned from the kernel to our corresponding | |
667 | lwp_info data structure. */ | |
668 | static htab_t lwp_lwpid_htab; | |
669 | ||
670 | /* Calculate a hash from a lwp_info's LWP PID. */ | |
671 | ||
672 | static hashval_t | |
673 | lwp_info_hash (const void *ap) | |
674 | { | |
675 | const struct lwp_info *lp = (struct lwp_info *) ap; | |
e38504b3 | 676 | pid_t pid = lp->ptid.lwp (); |
774113b0 PA |
677 | |
678 | return iterative_hash_object (pid, 0); | |
679 | } | |
680 | ||
681 | /* Equality function for the lwp_info hash table. Compares the LWP's | |
682 | PID. */ | |
683 | ||
684 | static int | |
685 | lwp_lwpid_htab_eq (const void *a, const void *b) | |
686 | { | |
687 | const struct lwp_info *entry = (const struct lwp_info *) a; | |
688 | const struct lwp_info *element = (const struct lwp_info *) b; | |
689 | ||
e38504b3 | 690 | return entry->ptid.lwp () == element->ptid.lwp (); |
774113b0 PA |
691 | } |
692 | ||
693 | /* Create the lwp_lwpid_htab hash table. */ | |
694 | ||
695 | static void | |
696 | lwp_lwpid_htab_create (void) | |
697 | { | |
698 | lwp_lwpid_htab = htab_create (100, lwp_info_hash, lwp_lwpid_htab_eq, NULL); | |
699 | } | |
700 | ||
701 | /* Add LP to the hash table. */ | |
702 | ||
703 | static void | |
704 | lwp_lwpid_htab_add_lwp (struct lwp_info *lp) | |
705 | { | |
706 | void **slot; | |
707 | ||
708 | slot = htab_find_slot (lwp_lwpid_htab, lp, INSERT); | |
709 | gdb_assert (slot != NULL && *slot == NULL); | |
710 | *slot = lp; | |
711 | } | |
712 | ||
713 | /* Head of doubly-linked list of known LWPs. Sorted by reverse | |
714 | creation order. This order is assumed in some cases. E.g., | |
715 | reaping status after killing alls lwps of a process: the leader LWP | |
716 | must be reaped last. */ | |
9f0bdab8 | 717 | struct lwp_info *lwp_list; |
774113b0 PA |
718 | |
719 | /* Add LP to sorted-by-reverse-creation-order doubly-linked list. */ | |
720 | ||
721 | static void | |
722 | lwp_list_add (struct lwp_info *lp) | |
723 | { | |
724 | lp->next = lwp_list; | |
725 | if (lwp_list != NULL) | |
726 | lwp_list->prev = lp; | |
727 | lwp_list = lp; | |
728 | } | |
729 | ||
730 | /* Remove LP from sorted-by-reverse-creation-order doubly-linked | |
731 | list. */ | |
732 | ||
733 | static void | |
734 | lwp_list_remove (struct lwp_info *lp) | |
735 | { | |
736 | /* Remove from sorted-by-creation-order list. */ | |
737 | if (lp->next != NULL) | |
738 | lp->next->prev = lp->prev; | |
739 | if (lp->prev != NULL) | |
740 | lp->prev->next = lp->next; | |
741 | if (lp == lwp_list) | |
742 | lwp_list = lp->next; | |
743 | } | |
744 | ||
d6b0e80f AC |
745 | \f |
746 | ||
d6b0e80f AC |
747 | /* Signal mask for use with sigsuspend in linux_nat_wait, initialized in |
748 | _initialize_linux_nat. */ | |
749 | static sigset_t suspend_mask; | |
750 | ||
7feb7d06 PA |
751 | /* Signals to block to make that sigsuspend work. */ |
752 | static sigset_t blocked_mask; | |
753 | ||
754 | /* SIGCHLD action. */ | |
755 | struct sigaction sigchld_action; | |
b84876c2 | 756 | |
7feb7d06 PA |
757 | /* Block child signals (SIGCHLD and linux threads signals), and store |
758 | the previous mask in PREV_MASK. */ | |
84e46146 | 759 | |
7feb7d06 PA |
760 | static void |
761 | block_child_signals (sigset_t *prev_mask) | |
762 | { | |
763 | /* Make sure SIGCHLD is blocked. */ | |
764 | if (!sigismember (&blocked_mask, SIGCHLD)) | |
765 | sigaddset (&blocked_mask, SIGCHLD); | |
766 | ||
767 | sigprocmask (SIG_BLOCK, &blocked_mask, prev_mask); | |
768 | } | |
769 | ||
770 | /* Restore child signals mask, previously returned by | |
771 | block_child_signals. */ | |
772 | ||
773 | static void | |
774 | restore_child_signals_mask (sigset_t *prev_mask) | |
775 | { | |
776 | sigprocmask (SIG_SETMASK, prev_mask, NULL); | |
777 | } | |
2455069d UW |
778 | |
779 | /* Mask of signals to pass directly to the inferior. */ | |
780 | static sigset_t pass_mask; | |
781 | ||
782 | /* Update signals to pass to the inferior. */ | |
f6ac5f3d | 783 | void |
adc6a863 PA |
784 | linux_nat_target::pass_signals |
785 | (gdb::array_view<const unsigned char> pass_signals) | |
2455069d UW |
786 | { |
787 | int signo; | |
788 | ||
789 | sigemptyset (&pass_mask); | |
790 | ||
791 | for (signo = 1; signo < NSIG; signo++) | |
792 | { | |
2ea28649 | 793 | int target_signo = gdb_signal_from_host (signo); |
adc6a863 | 794 | if (target_signo < pass_signals.size () && pass_signals[target_signo]) |
2455069d UW |
795 | sigaddset (&pass_mask, signo); |
796 | } | |
797 | } | |
798 | ||
d6b0e80f AC |
799 | \f |
800 | ||
801 | /* Prototypes for local functions. */ | |
d3a70e03 TT |
802 | static int stop_wait_callback (struct lwp_info *lp); |
803 | static int resume_stopped_resumed_lwps (struct lwp_info *lp, const ptid_t wait_ptid); | |
ced2dffb | 804 | static int check_ptrace_stopped_lwp_gone (struct lwp_info *lp); |
710151dd | 805 | |
d6b0e80f | 806 | \f |
d6b0e80f | 807 | |
7b50312a PA |
808 | /* Destroy and free LP. */ |
809 | ||
810 | static void | |
811 | lwp_free (struct lwp_info *lp) | |
812 | { | |
466eecee | 813 | /* Let the arch specific bits release arch_lwp_info. */ |
135340af | 814 | linux_target->low_delete_thread (lp->arch_private); |
466eecee | 815 | |
7b50312a PA |
816 | xfree (lp); |
817 | } | |
818 | ||
774113b0 | 819 | /* Traversal function for purge_lwp_list. */ |
d90e17a7 | 820 | |
774113b0 PA |
821 | static int |
822 | lwp_lwpid_htab_remove_pid (void **slot, void *info) | |
d90e17a7 | 823 | { |
774113b0 PA |
824 | struct lwp_info *lp = (struct lwp_info *) *slot; |
825 | int pid = *(int *) info; | |
d90e17a7 | 826 | |
e99b03dc | 827 | if (lp->ptid.pid () == pid) |
d90e17a7 | 828 | { |
774113b0 PA |
829 | htab_clear_slot (lwp_lwpid_htab, slot); |
830 | lwp_list_remove (lp); | |
831 | lwp_free (lp); | |
832 | } | |
d90e17a7 | 833 | |
774113b0 PA |
834 | return 1; |
835 | } | |
d90e17a7 | 836 | |
774113b0 PA |
837 | /* Remove all LWPs belong to PID from the lwp list. */ |
838 | ||
839 | static void | |
840 | purge_lwp_list (int pid) | |
841 | { | |
842 | htab_traverse_noresize (lwp_lwpid_htab, lwp_lwpid_htab_remove_pid, &pid); | |
d90e17a7 PA |
843 | } |
844 | ||
26cb8b7c PA |
845 | /* Add the LWP specified by PTID to the list. PTID is the first LWP |
846 | in the process. Return a pointer to the structure describing the | |
847 | new LWP. | |
848 | ||
849 | This differs from add_lwp in that we don't let the arch specific | |
850 | bits know about this new thread. Current clients of this callback | |
851 | take the opportunity to install watchpoints in the new thread, and | |
852 | we shouldn't do that for the first thread. If we're spawning a | |
853 | child ("run"), the thread executes the shell wrapper first, and we | |
854 | shouldn't touch it until it execs the program we want to debug. | |
855 | For "attach", it'd be okay to call the callback, but it's not | |
856 | necessary, because watchpoints can't yet have been inserted into | |
857 | the inferior. */ | |
d6b0e80f AC |
858 | |
859 | static struct lwp_info * | |
26cb8b7c | 860 | add_initial_lwp (ptid_t ptid) |
d6b0e80f AC |
861 | { |
862 | struct lwp_info *lp; | |
863 | ||
15a9e13e | 864 | gdb_assert (ptid.lwp_p ()); |
d6b0e80f | 865 | |
8d749320 | 866 | lp = XNEW (struct lwp_info); |
d6b0e80f AC |
867 | |
868 | memset (lp, 0, sizeof (struct lwp_info)); | |
869 | ||
25289eb2 | 870 | lp->last_resume_kind = resume_continue; |
d6b0e80f AC |
871 | lp->waitstatus.kind = TARGET_WAITKIND_IGNORE; |
872 | ||
873 | lp->ptid = ptid; | |
dc146f7c | 874 | lp->core = -1; |
d6b0e80f | 875 | |
774113b0 PA |
876 | /* Add to sorted-by-reverse-creation-order list. */ |
877 | lwp_list_add (lp); | |
878 | ||
879 | /* Add to keyed-by-pid htab. */ | |
880 | lwp_lwpid_htab_add_lwp (lp); | |
d6b0e80f | 881 | |
26cb8b7c PA |
882 | return lp; |
883 | } | |
884 | ||
885 | /* Add the LWP specified by PID to the list. Return a pointer to the | |
886 | structure describing the new LWP. The LWP should already be | |
887 | stopped. */ | |
888 | ||
889 | static struct lwp_info * | |
890 | add_lwp (ptid_t ptid) | |
891 | { | |
892 | struct lwp_info *lp; | |
893 | ||
894 | lp = add_initial_lwp (ptid); | |
895 | ||
6e012a6c PA |
896 | /* Let the arch specific bits know about this new thread. Current |
897 | clients of this callback take the opportunity to install | |
26cb8b7c PA |
898 | watchpoints in the new thread. We don't do this for the first |
899 | thread though. See add_initial_lwp. */ | |
135340af | 900 | linux_target->low_new_thread (lp); |
9f0bdab8 | 901 | |
d6b0e80f AC |
902 | return lp; |
903 | } | |
904 | ||
905 | /* Remove the LWP specified by PID from the list. */ | |
906 | ||
907 | static void | |
908 | delete_lwp (ptid_t ptid) | |
909 | { | |
774113b0 PA |
910 | struct lwp_info *lp; |
911 | void **slot; | |
912 | struct lwp_info dummy; | |
d6b0e80f | 913 | |
774113b0 PA |
914 | dummy.ptid = ptid; |
915 | slot = htab_find_slot (lwp_lwpid_htab, &dummy, NO_INSERT); | |
916 | if (slot == NULL) | |
917 | return; | |
d6b0e80f | 918 | |
774113b0 PA |
919 | lp = *(struct lwp_info **) slot; |
920 | gdb_assert (lp != NULL); | |
d6b0e80f | 921 | |
774113b0 | 922 | htab_clear_slot (lwp_lwpid_htab, slot); |
d6b0e80f | 923 | |
774113b0 PA |
924 | /* Remove from sorted-by-creation-order list. */ |
925 | lwp_list_remove (lp); | |
d6b0e80f | 926 | |
774113b0 | 927 | /* Release. */ |
7b50312a | 928 | lwp_free (lp); |
d6b0e80f AC |
929 | } |
930 | ||
931 | /* Return a pointer to the structure describing the LWP corresponding | |
932 | to PID. If no corresponding LWP could be found, return NULL. */ | |
933 | ||
934 | static struct lwp_info * | |
935 | find_lwp_pid (ptid_t ptid) | |
936 | { | |
937 | struct lwp_info *lp; | |
938 | int lwp; | |
774113b0 | 939 | struct lwp_info dummy; |
d6b0e80f | 940 | |
15a9e13e | 941 | if (ptid.lwp_p ()) |
e38504b3 | 942 | lwp = ptid.lwp (); |
d6b0e80f | 943 | else |
e99b03dc | 944 | lwp = ptid.pid (); |
d6b0e80f | 945 | |
fd79271b | 946 | dummy.ptid = ptid_t (0, lwp, 0); |
774113b0 PA |
947 | lp = (struct lwp_info *) htab_find (lwp_lwpid_htab, &dummy); |
948 | return lp; | |
d6b0e80f AC |
949 | } |
950 | ||
6d4ee8c6 | 951 | /* See nat/linux-nat.h. */ |
d6b0e80f AC |
952 | |
953 | struct lwp_info * | |
d90e17a7 | 954 | iterate_over_lwps (ptid_t filter, |
d3a70e03 | 955 | gdb::function_view<iterate_over_lwps_ftype> callback) |
d6b0e80f AC |
956 | { |
957 | struct lwp_info *lp, *lpnext; | |
958 | ||
959 | for (lp = lwp_list; lp; lp = lpnext) | |
960 | { | |
961 | lpnext = lp->next; | |
d90e17a7 | 962 | |
26a57c92 | 963 | if (lp->ptid.matches (filter)) |
d90e17a7 | 964 | { |
d3a70e03 | 965 | if (callback (lp) != 0) |
d90e17a7 PA |
966 | return lp; |
967 | } | |
d6b0e80f AC |
968 | } |
969 | ||
970 | return NULL; | |
971 | } | |
972 | ||
2277426b PA |
973 | /* Update our internal state when changing from one checkpoint to |
974 | another indicated by NEW_PTID. We can only switch single-threaded | |
975 | applications, so we only create one new LWP, and the previous list | |
976 | is discarded. */ | |
f973ed9c DJ |
977 | |
978 | void | |
979 | linux_nat_switch_fork (ptid_t new_ptid) | |
980 | { | |
981 | struct lwp_info *lp; | |
982 | ||
e99b03dc | 983 | purge_lwp_list (inferior_ptid.pid ()); |
2277426b | 984 | |
f973ed9c DJ |
985 | lp = add_lwp (new_ptid); |
986 | lp->stopped = 1; | |
e26af52f | 987 | |
2277426b PA |
988 | /* This changes the thread's ptid while preserving the gdb thread |
989 | num. Also changes the inferior pid, while preserving the | |
990 | inferior num. */ | |
991 | thread_change_ptid (inferior_ptid, new_ptid); | |
992 | ||
993 | /* We've just told GDB core that the thread changed target id, but, | |
994 | in fact, it really is a different thread, with different register | |
995 | contents. */ | |
996 | registers_changed (); | |
e26af52f DJ |
997 | } |
998 | ||
e26af52f DJ |
999 | /* Handle the exit of a single thread LP. */ |
1000 | ||
1001 | static void | |
1002 | exit_lwp (struct lwp_info *lp) | |
1003 | { | |
e09875d4 | 1004 | struct thread_info *th = find_thread_ptid (lp->ptid); |
063bfe2e VP |
1005 | |
1006 | if (th) | |
e26af52f | 1007 | { |
17faa917 | 1008 | if (print_thread_events) |
a068643d TT |
1009 | printf_unfiltered (_("[%s exited]\n"), |
1010 | target_pid_to_str (lp->ptid).c_str ()); | |
17faa917 | 1011 | |
00431a78 | 1012 | delete_thread (th); |
e26af52f DJ |
1013 | } |
1014 | ||
1015 | delete_lwp (lp->ptid); | |
1016 | } | |
1017 | ||
a0ef4274 DJ |
1018 | /* Wait for the LWP specified by LP, which we have just attached to. |
1019 | Returns a wait status for that LWP, to cache. */ | |
1020 | ||
1021 | static int | |
22827c51 | 1022 | linux_nat_post_attach_wait (ptid_t ptid, int *signalled) |
a0ef4274 | 1023 | { |
e38504b3 | 1024 | pid_t new_pid, pid = ptid.lwp (); |
a0ef4274 DJ |
1025 | int status; |
1026 | ||
644cebc9 | 1027 | if (linux_proc_pid_is_stopped (pid)) |
a0ef4274 DJ |
1028 | { |
1029 | if (debug_linux_nat) | |
1030 | fprintf_unfiltered (gdb_stdlog, | |
1031 | "LNPAW: Attaching to a stopped process\n"); | |
1032 | ||
1033 | /* The process is definitely stopped. It is in a job control | |
1034 | stop, unless the kernel predates the TASK_STOPPED / | |
1035 | TASK_TRACED distinction, in which case it might be in a | |
1036 | ptrace stop. Make sure it is in a ptrace stop; from there we | |
1037 | can kill it, signal it, et cetera. | |
1038 | ||
1039 | First make sure there is a pending SIGSTOP. Since we are | |
1040 | already attached, the process can not transition from stopped | |
1041 | to running without a PTRACE_CONT; so we know this signal will | |
1042 | go into the queue. The SIGSTOP generated by PTRACE_ATTACH is | |
1043 | probably already in the queue (unless this kernel is old | |
1044 | enough to use TASK_STOPPED for ptrace stops); but since SIGSTOP | |
1045 | is not an RT signal, it can only be queued once. */ | |
1046 | kill_lwp (pid, SIGSTOP); | |
1047 | ||
1048 | /* Finally, resume the stopped process. This will deliver the SIGSTOP | |
1049 | (or a higher priority signal, just like normal PTRACE_ATTACH). */ | |
1050 | ptrace (PTRACE_CONT, pid, 0, 0); | |
1051 | } | |
1052 | ||
1053 | /* Make sure the initial process is stopped. The user-level threads | |
1054 | layer might want to poke around in the inferior, and that won't | |
1055 | work if things haven't stabilized yet. */ | |
4a6ed09b | 1056 | new_pid = my_waitpid (pid, &status, __WALL); |
dacc9cb2 PP |
1057 | gdb_assert (pid == new_pid); |
1058 | ||
1059 | if (!WIFSTOPPED (status)) | |
1060 | { | |
1061 | /* The pid we tried to attach has apparently just exited. */ | |
1062 | if (debug_linux_nat) | |
1063 | fprintf_unfiltered (gdb_stdlog, "LNPAW: Failed to stop %d: %s", | |
1064 | pid, status_to_str (status)); | |
1065 | return status; | |
1066 | } | |
a0ef4274 DJ |
1067 | |
1068 | if (WSTOPSIG (status) != SIGSTOP) | |
1069 | { | |
1070 | *signalled = 1; | |
1071 | if (debug_linux_nat) | |
1072 | fprintf_unfiltered (gdb_stdlog, | |
1073 | "LNPAW: Received %s after attaching\n", | |
1074 | status_to_str (status)); | |
1075 | } | |
1076 | ||
1077 | return status; | |
1078 | } | |
1079 | ||
f6ac5f3d PA |
1080 | void |
1081 | linux_nat_target::create_inferior (const char *exec_file, | |
1082 | const std::string &allargs, | |
1083 | char **env, int from_tty) | |
b84876c2 | 1084 | { |
41272101 TT |
1085 | maybe_disable_address_space_randomization restore_personality |
1086 | (disable_randomization); | |
b84876c2 PA |
1087 | |
1088 | /* The fork_child mechanism is synchronous and calls target_wait, so | |
1089 | we have to mask the async mode. */ | |
1090 | ||
2455069d | 1091 | /* Make sure we report all signals during startup. */ |
adc6a863 | 1092 | pass_signals ({}); |
2455069d | 1093 | |
f6ac5f3d | 1094 | inf_ptrace_target::create_inferior (exec_file, allargs, env, from_tty); |
b84876c2 PA |
1095 | } |
1096 | ||
8784d563 PA |
1097 | /* Callback for linux_proc_attach_tgid_threads. Attach to PTID if not |
1098 | already attached. Returns true if a new LWP is found, false | |
1099 | otherwise. */ | |
1100 | ||
1101 | static int | |
1102 | attach_proc_task_lwp_callback (ptid_t ptid) | |
1103 | { | |
1104 | struct lwp_info *lp; | |
1105 | ||
1106 | /* Ignore LWPs we're already attached to. */ | |
1107 | lp = find_lwp_pid (ptid); | |
1108 | if (lp == NULL) | |
1109 | { | |
e38504b3 | 1110 | int lwpid = ptid.lwp (); |
8784d563 PA |
1111 | |
1112 | if (ptrace (PTRACE_ATTACH, lwpid, 0, 0) < 0) | |
1113 | { | |
1114 | int err = errno; | |
1115 | ||
1116 | /* Be quiet if we simply raced with the thread exiting. | |
1117 | EPERM is returned if the thread's task still exists, and | |
1118 | is marked as exited or zombie, as well as other | |
1119 | conditions, so in that case, confirm the status in | |
1120 | /proc/PID/status. */ | |
1121 | if (err == ESRCH | |
1122 | || (err == EPERM && linux_proc_pid_is_gone (lwpid))) | |
1123 | { | |
1124 | if (debug_linux_nat) | |
1125 | { | |
1126 | fprintf_unfiltered (gdb_stdlog, | |
1127 | "Cannot attach to lwp %d: " | |
1128 | "thread is gone (%d: %s)\n", | |
1129 | lwpid, err, safe_strerror (err)); | |
1130 | } | |
1131 | } | |
1132 | else | |
1133 | { | |
4d9b86e1 | 1134 | std::string reason |
50fa3001 | 1135 | = linux_ptrace_attach_fail_reason_string (ptid, err); |
4d9b86e1 | 1136 | |
f71f0b0d | 1137 | warning (_("Cannot attach to lwp %d: %s"), |
4d9b86e1 | 1138 | lwpid, reason.c_str ()); |
8784d563 PA |
1139 | } |
1140 | } | |
1141 | else | |
1142 | { | |
1143 | if (debug_linux_nat) | |
1144 | fprintf_unfiltered (gdb_stdlog, | |
1145 | "PTRACE_ATTACH %s, 0, 0 (OK)\n", | |
a068643d | 1146 | target_pid_to_str (ptid).c_str ()); |
8784d563 PA |
1147 | |
1148 | lp = add_lwp (ptid); | |
8784d563 PA |
1149 | |
1150 | /* The next time we wait for this LWP we'll see a SIGSTOP as | |
1151 | PTRACE_ATTACH brings it to a halt. */ | |
1152 | lp->signalled = 1; | |
1153 | ||
1154 | /* We need to wait for a stop before being able to make the | |
1155 | next ptrace call on this LWP. */ | |
1156 | lp->must_set_ptrace_flags = 1; | |
026a9174 PA |
1157 | |
1158 | /* So that wait collects the SIGSTOP. */ | |
1159 | lp->resumed = 1; | |
1160 | ||
1161 | /* Also add the LWP to gdb's thread list, in case a | |
1162 | matching libthread_db is not found (or the process uses | |
1163 | raw clone). */ | |
1164 | add_thread (lp->ptid); | |
1165 | set_running (lp->ptid, 1); | |
1166 | set_executing (lp->ptid, 1); | |
8784d563 PA |
1167 | } |
1168 | ||
1169 | return 1; | |
1170 | } | |
1171 | return 0; | |
1172 | } | |
1173 | ||
f6ac5f3d PA |
1174 | void |
1175 | linux_nat_target::attach (const char *args, int from_tty) | |
d6b0e80f AC |
1176 | { |
1177 | struct lwp_info *lp; | |
d6b0e80f | 1178 | int status; |
af990527 | 1179 | ptid_t ptid; |
d6b0e80f | 1180 | |
2455069d | 1181 | /* Make sure we report all signals during attach. */ |
adc6a863 | 1182 | pass_signals ({}); |
2455069d | 1183 | |
a70b8144 | 1184 | try |
87b0bb13 | 1185 | { |
f6ac5f3d | 1186 | inf_ptrace_target::attach (args, from_tty); |
87b0bb13 | 1187 | } |
230d2906 | 1188 | catch (const gdb_exception_error &ex) |
87b0bb13 JK |
1189 | { |
1190 | pid_t pid = parse_pid_to_attach (args); | |
50fa3001 | 1191 | std::string reason = linux_ptrace_attach_fail_reason (pid); |
87b0bb13 | 1192 | |
4d9b86e1 | 1193 | if (!reason.empty ()) |
3d6e9d23 TT |
1194 | throw_error (ex.error, "warning: %s\n%s", reason.c_str (), |
1195 | ex.what ()); | |
7ae1a6a6 | 1196 | else |
3d6e9d23 | 1197 | throw_error (ex.error, "%s", ex.what ()); |
87b0bb13 | 1198 | } |
d6b0e80f | 1199 | |
af990527 PA |
1200 | /* The ptrace base target adds the main thread with (pid,0,0) |
1201 | format. Decorate it with lwp info. */ | |
e99b03dc TT |
1202 | ptid = ptid_t (inferior_ptid.pid (), |
1203 | inferior_ptid.pid (), | |
fd79271b | 1204 | 0); |
af990527 PA |
1205 | thread_change_ptid (inferior_ptid, ptid); |
1206 | ||
9f0bdab8 | 1207 | /* Add the initial process as the first LWP to the list. */ |
26cb8b7c | 1208 | lp = add_initial_lwp (ptid); |
a0ef4274 | 1209 | |
22827c51 | 1210 | status = linux_nat_post_attach_wait (lp->ptid, &lp->signalled); |
dacc9cb2 PP |
1211 | if (!WIFSTOPPED (status)) |
1212 | { | |
1213 | if (WIFEXITED (status)) | |
1214 | { | |
1215 | int exit_code = WEXITSTATUS (status); | |
1216 | ||
223ffa71 | 1217 | target_terminal::ours (); |
bc1e6c81 | 1218 | target_mourn_inferior (inferior_ptid); |
dacc9cb2 PP |
1219 | if (exit_code == 0) |
1220 | error (_("Unable to attach: program exited normally.")); | |
1221 | else | |
1222 | error (_("Unable to attach: program exited with code %d."), | |
1223 | exit_code); | |
1224 | } | |
1225 | else if (WIFSIGNALED (status)) | |
1226 | { | |
2ea28649 | 1227 | enum gdb_signal signo; |
dacc9cb2 | 1228 | |
223ffa71 | 1229 | target_terminal::ours (); |
bc1e6c81 | 1230 | target_mourn_inferior (inferior_ptid); |
dacc9cb2 | 1231 | |
2ea28649 | 1232 | signo = gdb_signal_from_host (WTERMSIG (status)); |
dacc9cb2 PP |
1233 | error (_("Unable to attach: program terminated with signal " |
1234 | "%s, %s."), | |
2ea28649 PA |
1235 | gdb_signal_to_name (signo), |
1236 | gdb_signal_to_string (signo)); | |
dacc9cb2 PP |
1237 | } |
1238 | ||
1239 | internal_error (__FILE__, __LINE__, | |
1240 | _("unexpected status %d for PID %ld"), | |
e38504b3 | 1241 | status, (long) ptid.lwp ()); |
dacc9cb2 PP |
1242 | } |
1243 | ||
a0ef4274 | 1244 | lp->stopped = 1; |
9f0bdab8 | 1245 | |
a0ef4274 | 1246 | /* Save the wait status to report later. */ |
d6b0e80f | 1247 | lp->resumed = 1; |
a0ef4274 DJ |
1248 | if (debug_linux_nat) |
1249 | fprintf_unfiltered (gdb_stdlog, | |
1250 | "LNA: waitpid %ld, saving status %s\n", | |
e99b03dc | 1251 | (long) lp->ptid.pid (), status_to_str (status)); |
710151dd | 1252 | |
7feb7d06 PA |
1253 | lp->status = status; |
1254 | ||
8784d563 PA |
1255 | /* We must attach to every LWP. If /proc is mounted, use that to |
1256 | find them now. The inferior may be using raw clone instead of | |
1257 | using pthreads. But even if it is using pthreads, thread_db | |
1258 | walks structures in the inferior's address space to find the list | |
1259 | of threads/LWPs, and those structures may well be corrupted. | |
1260 | Note that once thread_db is loaded, we'll still use it to list | |
1261 | threads and associate pthread info with each LWP. */ | |
e99b03dc | 1262 | linux_proc_attach_tgid_threads (lp->ptid.pid (), |
8784d563 PA |
1263 | attach_proc_task_lwp_callback); |
1264 | ||
7feb7d06 | 1265 | if (target_can_async_p ()) |
6a3753b3 | 1266 | target_async (1); |
d6b0e80f AC |
1267 | } |
1268 | ||
ced2dffb PA |
1269 | /* Get pending signal of THREAD as a host signal number, for detaching |
1270 | purposes. This is the signal the thread last stopped for, which we | |
1271 | need to deliver to the thread when detaching, otherwise, it'd be | |
1272 | suppressed/lost. */ | |
1273 | ||
a0ef4274 | 1274 | static int |
ced2dffb | 1275 | get_detach_signal (struct lwp_info *lp) |
a0ef4274 | 1276 | { |
a493e3e2 | 1277 | enum gdb_signal signo = GDB_SIGNAL_0; |
ca2163eb PA |
1278 | |
1279 | /* If we paused threads momentarily, we may have stored pending | |
1280 | events in lp->status or lp->waitstatus (see stop_wait_callback), | |
1281 | and GDB core hasn't seen any signal for those threads. | |
1282 | Otherwise, the last signal reported to the core is found in the | |
1283 | thread object's stop_signal. | |
1284 | ||
1285 | There's a corner case that isn't handled here at present. Only | |
1286 | if the thread stopped with a TARGET_WAITKIND_STOPPED does | |
1287 | stop_signal make sense as a real signal to pass to the inferior. | |
1288 | Some catchpoint related events, like | |
1289 | TARGET_WAITKIND_(V)FORK|EXEC|SYSCALL, have their stop_signal set | |
a493e3e2 | 1290 | to GDB_SIGNAL_SIGTRAP when the catchpoint triggers. But, |
ca2163eb PA |
1291 | those traps are debug API (ptrace in our case) related and |
1292 | induced; the inferior wouldn't see them if it wasn't being | |
1293 | traced. Hence, we should never pass them to the inferior, even | |
1294 | when set to pass state. Since this corner case isn't handled by | |
1295 | infrun.c when proceeding with a signal, for consistency, neither | |
1296 | do we handle it here (or elsewhere in the file we check for | |
1297 | signal pass state). Normally SIGTRAP isn't set to pass state, so | |
1298 | this is really a corner case. */ | |
1299 | ||
1300 | if (lp->waitstatus.kind != TARGET_WAITKIND_IGNORE) | |
a493e3e2 | 1301 | signo = GDB_SIGNAL_0; /* a pending ptrace event, not a real signal. */ |
ca2163eb | 1302 | else if (lp->status) |
2ea28649 | 1303 | signo = gdb_signal_from_host (WSTOPSIG (lp->status)); |
00431a78 | 1304 | else |
ca2163eb PA |
1305 | { |
1306 | struct thread_info *tp = find_thread_ptid (lp->ptid); | |
e0881a8e | 1307 | |
00431a78 | 1308 | if (target_is_non_stop_p () && !tp->executing) |
ca2163eb | 1309 | { |
00431a78 PA |
1310 | if (tp->suspend.waitstatus_pending_p) |
1311 | signo = tp->suspend.waitstatus.value.sig; | |
1312 | else | |
1313 | signo = tp->suspend.stop_signal; | |
1314 | } | |
1315 | else if (!target_is_non_stop_p ()) | |
1316 | { | |
1317 | struct target_waitstatus last; | |
1318 | ptid_t last_ptid; | |
1319 | ||
1320 | get_last_target_status (&last_ptid, &last); | |
e0881a8e | 1321 | |
e38504b3 | 1322 | if (lp->ptid.lwp () == last_ptid.lwp ()) |
00431a78 | 1323 | signo = tp->suspend.stop_signal; |
4c28f408 | 1324 | } |
ca2163eb | 1325 | } |
4c28f408 | 1326 | |
a493e3e2 | 1327 | if (signo == GDB_SIGNAL_0) |
ca2163eb PA |
1328 | { |
1329 | if (debug_linux_nat) | |
1330 | fprintf_unfiltered (gdb_stdlog, | |
1331 | "GPT: lwp %s has no pending signal\n", | |
a068643d | 1332 | target_pid_to_str (lp->ptid).c_str ()); |
ca2163eb PA |
1333 | } |
1334 | else if (!signal_pass_state (signo)) | |
1335 | { | |
1336 | if (debug_linux_nat) | |
3e43a32a MS |
1337 | fprintf_unfiltered (gdb_stdlog, |
1338 | "GPT: lwp %s had signal %s, " | |
1339 | "but it is in no pass state\n", | |
a068643d | 1340 | target_pid_to_str (lp->ptid).c_str (), |
2ea28649 | 1341 | gdb_signal_to_string (signo)); |
a0ef4274 | 1342 | } |
a0ef4274 | 1343 | else |
4c28f408 | 1344 | { |
ca2163eb PA |
1345 | if (debug_linux_nat) |
1346 | fprintf_unfiltered (gdb_stdlog, | |
1347 | "GPT: lwp %s has pending signal %s\n", | |
a068643d | 1348 | target_pid_to_str (lp->ptid).c_str (), |
2ea28649 | 1349 | gdb_signal_to_string (signo)); |
ced2dffb PA |
1350 | |
1351 | return gdb_signal_to_host (signo); | |
4c28f408 | 1352 | } |
a0ef4274 DJ |
1353 | |
1354 | return 0; | |
1355 | } | |
1356 | ||
ced2dffb PA |
1357 | /* Detach from LP. If SIGNO_P is non-NULL, then it points to the |
1358 | signal number that should be passed to the LWP when detaching. | |
1359 | Otherwise pass any pending signal the LWP may have, if any. */ | |
1360 | ||
1361 | static void | |
1362 | detach_one_lwp (struct lwp_info *lp, int *signo_p) | |
d6b0e80f | 1363 | { |
e38504b3 | 1364 | int lwpid = lp->ptid.lwp (); |
ced2dffb PA |
1365 | int signo; |
1366 | ||
d6b0e80f AC |
1367 | gdb_assert (lp->status == 0 || WIFSTOPPED (lp->status)); |
1368 | ||
1369 | if (debug_linux_nat && lp->status) | |
1370 | fprintf_unfiltered (gdb_stdlog, "DC: Pending %s for %s on detach.\n", | |
1371 | strsignal (WSTOPSIG (lp->status)), | |
a068643d | 1372 | target_pid_to_str (lp->ptid).c_str ()); |
d6b0e80f | 1373 | |
a0ef4274 DJ |
1374 | /* If there is a pending SIGSTOP, get rid of it. */ |
1375 | if (lp->signalled) | |
d6b0e80f | 1376 | { |
d6b0e80f AC |
1377 | if (debug_linux_nat) |
1378 | fprintf_unfiltered (gdb_stdlog, | |
a0ef4274 | 1379 | "DC: Sending SIGCONT to %s\n", |
a068643d | 1380 | target_pid_to_str (lp->ptid).c_str ()); |
d6b0e80f | 1381 | |
ced2dffb | 1382 | kill_lwp (lwpid, SIGCONT); |
d6b0e80f | 1383 | lp->signalled = 0; |
d6b0e80f AC |
1384 | } |
1385 | ||
ced2dffb | 1386 | if (signo_p == NULL) |
d6b0e80f | 1387 | { |
a0ef4274 | 1388 | /* Pass on any pending signal for this LWP. */ |
ced2dffb PA |
1389 | signo = get_detach_signal (lp); |
1390 | } | |
1391 | else | |
1392 | signo = *signo_p; | |
a0ef4274 | 1393 | |
ced2dffb PA |
1394 | /* Preparing to resume may try to write registers, and fail if the |
1395 | lwp is zombie. If that happens, ignore the error. We'll handle | |
1396 | it below, when detach fails with ESRCH. */ | |
a70b8144 | 1397 | try |
ced2dffb | 1398 | { |
135340af | 1399 | linux_target->low_prepare_to_resume (lp); |
ced2dffb | 1400 | } |
230d2906 | 1401 | catch (const gdb_exception_error &ex) |
ced2dffb PA |
1402 | { |
1403 | if (!check_ptrace_stopped_lwp_gone (lp)) | |
eedc3f4f | 1404 | throw; |
ced2dffb | 1405 | } |
d6b0e80f | 1406 | |
ced2dffb PA |
1407 | if (ptrace (PTRACE_DETACH, lwpid, 0, signo) < 0) |
1408 | { | |
1409 | int save_errno = errno; | |
1410 | ||
1411 | /* We know the thread exists, so ESRCH must mean the lwp is | |
1412 | zombie. This can happen if one of the already-detached | |
1413 | threads exits the whole thread group. In that case we're | |
1414 | still attached, and must reap the lwp. */ | |
1415 | if (save_errno == ESRCH) | |
1416 | { | |
1417 | int ret, status; | |
d6b0e80f | 1418 | |
ced2dffb PA |
1419 | ret = my_waitpid (lwpid, &status, __WALL); |
1420 | if (ret == -1) | |
1421 | { | |
1422 | warning (_("Couldn't reap LWP %d while detaching: %s"), | |
1423 | lwpid, strerror (errno)); | |
1424 | } | |
1425 | else if (!WIFEXITED (status) && !WIFSIGNALED (status)) | |
1426 | { | |
1427 | warning (_("Reaping LWP %d while detaching " | |
1428 | "returned unexpected status 0x%x"), | |
1429 | lwpid, status); | |
1430 | } | |
1431 | } | |
1432 | else | |
1433 | { | |
a068643d TT |
1434 | error (_("Can't detach %s: %s"), |
1435 | target_pid_to_str (lp->ptid).c_str (), | |
ced2dffb PA |
1436 | safe_strerror (save_errno)); |
1437 | } | |
d6b0e80f | 1438 | } |
ced2dffb PA |
1439 | else if (debug_linux_nat) |
1440 | { | |
1441 | fprintf_unfiltered (gdb_stdlog, | |
1442 | "PTRACE_DETACH (%s, %s, 0) (OK)\n", | |
a068643d | 1443 | target_pid_to_str (lp->ptid).c_str (), |
ced2dffb PA |
1444 | strsignal (signo)); |
1445 | } | |
1446 | ||
1447 | delete_lwp (lp->ptid); | |
1448 | } | |
d6b0e80f | 1449 | |
ced2dffb | 1450 | static int |
d3a70e03 | 1451 | detach_callback (struct lwp_info *lp) |
ced2dffb PA |
1452 | { |
1453 | /* We don't actually detach from the thread group leader just yet. | |
1454 | If the thread group exits, we must reap the zombie clone lwps | |
1455 | before we're able to reap the leader. */ | |
e38504b3 | 1456 | if (lp->ptid.lwp () != lp->ptid.pid ()) |
ced2dffb | 1457 | detach_one_lwp (lp, NULL); |
d6b0e80f AC |
1458 | return 0; |
1459 | } | |
1460 | ||
f6ac5f3d PA |
1461 | void |
1462 | linux_nat_target::detach (inferior *inf, int from_tty) | |
d6b0e80f | 1463 | { |
d90e17a7 | 1464 | struct lwp_info *main_lwp; |
bc09b0c1 | 1465 | int pid = inf->pid; |
a0ef4274 | 1466 | |
ae5e0686 MK |
1467 | /* Don't unregister from the event loop, as there may be other |
1468 | inferiors running. */ | |
b84876c2 | 1469 | |
4c28f408 PA |
1470 | /* Stop all threads before detaching. ptrace requires that the |
1471 | thread is stopped to sucessfully detach. */ | |
d3a70e03 | 1472 | iterate_over_lwps (ptid_t (pid), stop_callback); |
4c28f408 PA |
1473 | /* ... and wait until all of them have reported back that |
1474 | they're no longer running. */ | |
d3a70e03 | 1475 | iterate_over_lwps (ptid_t (pid), stop_wait_callback); |
4c28f408 | 1476 | |
d3a70e03 | 1477 | iterate_over_lwps (ptid_t (pid), detach_callback); |
d6b0e80f AC |
1478 | |
1479 | /* Only the initial process should be left right now. */ | |
bc09b0c1 | 1480 | gdb_assert (num_lwps (pid) == 1); |
d90e17a7 | 1481 | |
f2907e49 | 1482 | main_lwp = find_lwp_pid (ptid_t (pid)); |
d6b0e80f | 1483 | |
7a7d3353 PA |
1484 | if (forks_exist_p ()) |
1485 | { | |
1486 | /* Multi-fork case. The current inferior_ptid is being detached | |
1487 | from, but there are other viable forks to debug. Detach from | |
1488 | the current fork, and context-switch to the first | |
1489 | available. */ | |
6bd6f3b6 | 1490 | linux_fork_detach (from_tty); |
7a7d3353 PA |
1491 | } |
1492 | else | |
ced2dffb | 1493 | { |
ced2dffb PA |
1494 | target_announce_detach (from_tty); |
1495 | ||
6bd6f3b6 SM |
1496 | /* Pass on any pending signal for the last LWP. */ |
1497 | int signo = get_detach_signal (main_lwp); | |
ced2dffb PA |
1498 | |
1499 | detach_one_lwp (main_lwp, &signo); | |
1500 | ||
f6ac5f3d | 1501 | detach_success (inf); |
ced2dffb | 1502 | } |
d6b0e80f AC |
1503 | } |
1504 | ||
8a99810d PA |
1505 | /* Resume execution of the inferior process. If STEP is nonzero, |
1506 | single-step it. If SIGNAL is nonzero, give it that signal. */ | |
1507 | ||
1508 | static void | |
23f238d3 PA |
1509 | linux_resume_one_lwp_throw (struct lwp_info *lp, int step, |
1510 | enum gdb_signal signo) | |
8a99810d | 1511 | { |
8a99810d | 1512 | lp->step = step; |
9c02b525 PA |
1513 | |
1514 | /* stop_pc doubles as the PC the LWP had when it was last resumed. | |
1515 | We only presently need that if the LWP is stepped though (to | |
1516 | handle the case of stepping a breakpoint instruction). */ | |
1517 | if (step) | |
1518 | { | |
1519 | struct regcache *regcache = get_thread_regcache (lp->ptid); | |
1520 | ||
1521 | lp->stop_pc = regcache_read_pc (regcache); | |
1522 | } | |
1523 | else | |
1524 | lp->stop_pc = 0; | |
1525 | ||
135340af | 1526 | linux_target->low_prepare_to_resume (lp); |
f6ac5f3d | 1527 | linux_target->low_resume (lp->ptid, step, signo); |
23f238d3 PA |
1528 | |
1529 | /* Successfully resumed. Clear state that no longer makes sense, | |
1530 | and mark the LWP as running. Must not do this before resuming | |
1531 | otherwise if that fails other code will be confused. E.g., we'd | |
1532 | later try to stop the LWP and hang forever waiting for a stop | |
1533 | status. Note that we must not throw after this is cleared, | |
1534 | otherwise handle_zombie_lwp_error would get confused. */ | |
8a99810d | 1535 | lp->stopped = 0; |
1ad3de98 | 1536 | lp->core = -1; |
23f238d3 | 1537 | lp->stop_reason = TARGET_STOPPED_BY_NO_REASON; |
8a99810d PA |
1538 | registers_changed_ptid (lp->ptid); |
1539 | } | |
1540 | ||
23f238d3 PA |
1541 | /* Called when we try to resume a stopped LWP and that errors out. If |
1542 | the LWP is no longer in ptrace-stopped state (meaning it's zombie, | |
1543 | or about to become), discard the error, clear any pending status | |
1544 | the LWP may have, and return true (we'll collect the exit status | |
1545 | soon enough). Otherwise, return false. */ | |
1546 | ||
1547 | static int | |
1548 | check_ptrace_stopped_lwp_gone (struct lwp_info *lp) | |
1549 | { | |
1550 | /* If we get an error after resuming the LWP successfully, we'd | |
1551 | confuse !T state for the LWP being gone. */ | |
1552 | gdb_assert (lp->stopped); | |
1553 | ||
1554 | /* We can't just check whether the LWP is in 'Z (Zombie)' state, | |
1555 | because even if ptrace failed with ESRCH, the tracee may be "not | |
1556 | yet fully dead", but already refusing ptrace requests. In that | |
1557 | case the tracee has 'R (Running)' state for a little bit | |
1558 | (observed in Linux 3.18). See also the note on ESRCH in the | |
1559 | ptrace(2) man page. Instead, check whether the LWP has any state | |
1560 | other than ptrace-stopped. */ | |
1561 | ||
1562 | /* Don't assume anything if /proc/PID/status can't be read. */ | |
e38504b3 | 1563 | if (linux_proc_pid_is_trace_stopped_nowarn (lp->ptid.lwp ()) == 0) |
23f238d3 PA |
1564 | { |
1565 | lp->stop_reason = TARGET_STOPPED_BY_NO_REASON; | |
1566 | lp->status = 0; | |
1567 | lp->waitstatus.kind = TARGET_WAITKIND_IGNORE; | |
1568 | return 1; | |
1569 | } | |
1570 | return 0; | |
1571 | } | |
1572 | ||
1573 | /* Like linux_resume_one_lwp_throw, but no error is thrown if the LWP | |
1574 | disappears while we try to resume it. */ | |
1575 | ||
1576 | static void | |
1577 | linux_resume_one_lwp (struct lwp_info *lp, int step, enum gdb_signal signo) | |
1578 | { | |
a70b8144 | 1579 | try |
23f238d3 PA |
1580 | { |
1581 | linux_resume_one_lwp_throw (lp, step, signo); | |
1582 | } | |
230d2906 | 1583 | catch (const gdb_exception_error &ex) |
23f238d3 PA |
1584 | { |
1585 | if (!check_ptrace_stopped_lwp_gone (lp)) | |
eedc3f4f | 1586 | throw; |
23f238d3 | 1587 | } |
23f238d3 PA |
1588 | } |
1589 | ||
d6b0e80f AC |
1590 | /* Resume LP. */ |
1591 | ||
25289eb2 | 1592 | static void |
e5ef252a | 1593 | resume_lwp (struct lwp_info *lp, int step, enum gdb_signal signo) |
d6b0e80f | 1594 | { |
25289eb2 | 1595 | if (lp->stopped) |
6c95b8df | 1596 | { |
c9657e70 | 1597 | struct inferior *inf = find_inferior_ptid (lp->ptid); |
25289eb2 PA |
1598 | |
1599 | if (inf->vfork_child != NULL) | |
1600 | { | |
1601 | if (debug_linux_nat) | |
1602 | fprintf_unfiltered (gdb_stdlog, | |
1603 | "RC: Not resuming %s (vfork parent)\n", | |
a068643d | 1604 | target_pid_to_str (lp->ptid).c_str ()); |
25289eb2 | 1605 | } |
8a99810d | 1606 | else if (!lwp_status_pending_p (lp)) |
25289eb2 PA |
1607 | { |
1608 | if (debug_linux_nat) | |
1609 | fprintf_unfiltered (gdb_stdlog, | |
e5ef252a | 1610 | "RC: Resuming sibling %s, %s, %s\n", |
a068643d | 1611 | target_pid_to_str (lp->ptid).c_str (), |
e5ef252a PA |
1612 | (signo != GDB_SIGNAL_0 |
1613 | ? strsignal (gdb_signal_to_host (signo)) | |
1614 | : "0"), | |
1615 | step ? "step" : "resume"); | |
25289eb2 | 1616 | |
8a99810d | 1617 | linux_resume_one_lwp (lp, step, signo); |
25289eb2 PA |
1618 | } |
1619 | else | |
1620 | { | |
1621 | if (debug_linux_nat) | |
1622 | fprintf_unfiltered (gdb_stdlog, | |
1623 | "RC: Not resuming sibling %s (has pending)\n", | |
a068643d | 1624 | target_pid_to_str (lp->ptid).c_str ()); |
25289eb2 | 1625 | } |
6c95b8df | 1626 | } |
25289eb2 | 1627 | else |
d6b0e80f | 1628 | { |
d90e17a7 PA |
1629 | if (debug_linux_nat) |
1630 | fprintf_unfiltered (gdb_stdlog, | |
25289eb2 | 1631 | "RC: Not resuming sibling %s (not stopped)\n", |
a068643d | 1632 | target_pid_to_str (lp->ptid).c_str ()); |
d6b0e80f | 1633 | } |
25289eb2 | 1634 | } |
d6b0e80f | 1635 | |
8817a6f2 PA |
1636 | /* Callback for iterate_over_lwps. If LWP is EXCEPT, do nothing. |
1637 | Resume LWP with the last stop signal, if it is in pass state. */ | |
e5ef252a | 1638 | |
25289eb2 | 1639 | static int |
d3a70e03 | 1640 | linux_nat_resume_callback (struct lwp_info *lp, struct lwp_info *except) |
25289eb2 | 1641 | { |
e5ef252a PA |
1642 | enum gdb_signal signo = GDB_SIGNAL_0; |
1643 | ||
8817a6f2 PA |
1644 | if (lp == except) |
1645 | return 0; | |
1646 | ||
e5ef252a PA |
1647 | if (lp->stopped) |
1648 | { | |
1649 | struct thread_info *thread; | |
1650 | ||
1651 | thread = find_thread_ptid (lp->ptid); | |
1652 | if (thread != NULL) | |
1653 | { | |
70509625 | 1654 | signo = thread->suspend.stop_signal; |
e5ef252a PA |
1655 | thread->suspend.stop_signal = GDB_SIGNAL_0; |
1656 | } | |
1657 | } | |
1658 | ||
1659 | resume_lwp (lp, 0, signo); | |
d6b0e80f AC |
1660 | return 0; |
1661 | } | |
1662 | ||
1663 | static int | |
d3a70e03 | 1664 | resume_clear_callback (struct lwp_info *lp) |
d6b0e80f AC |
1665 | { |
1666 | lp->resumed = 0; | |
25289eb2 | 1667 | lp->last_resume_kind = resume_stop; |
d6b0e80f AC |
1668 | return 0; |
1669 | } | |
1670 | ||
1671 | static int | |
d3a70e03 | 1672 | resume_set_callback (struct lwp_info *lp) |
d6b0e80f AC |
1673 | { |
1674 | lp->resumed = 1; | |
25289eb2 | 1675 | lp->last_resume_kind = resume_continue; |
d6b0e80f AC |
1676 | return 0; |
1677 | } | |
1678 | ||
f6ac5f3d PA |
1679 | void |
1680 | linux_nat_target::resume (ptid_t ptid, int step, enum gdb_signal signo) | |
d6b0e80f AC |
1681 | { |
1682 | struct lwp_info *lp; | |
d90e17a7 | 1683 | int resume_many; |
d6b0e80f | 1684 | |
76f50ad1 DJ |
1685 | if (debug_linux_nat) |
1686 | fprintf_unfiltered (gdb_stdlog, | |
1687 | "LLR: Preparing to %s %s, %s, inferior_ptid %s\n", | |
1688 | step ? "step" : "resume", | |
a068643d | 1689 | target_pid_to_str (ptid).c_str (), |
a493e3e2 | 1690 | (signo != GDB_SIGNAL_0 |
2ea28649 | 1691 | ? strsignal (gdb_signal_to_host (signo)) : "0"), |
a068643d | 1692 | target_pid_to_str (inferior_ptid).c_str ()); |
76f50ad1 | 1693 | |
d6b0e80f | 1694 | /* A specific PTID means `step only this process id'. */ |
d7e15655 | 1695 | resume_many = (minus_one_ptid == ptid |
0e998d96 | 1696 | || ptid.is_pid ()); |
4c28f408 | 1697 | |
e3e9f5a2 | 1698 | /* Mark the lwps we're resuming as resumed. */ |
d3a70e03 | 1699 | iterate_over_lwps (ptid, resume_set_callback); |
d6b0e80f | 1700 | |
d90e17a7 PA |
1701 | /* See if it's the current inferior that should be handled |
1702 | specially. */ | |
1703 | if (resume_many) | |
1704 | lp = find_lwp_pid (inferior_ptid); | |
1705 | else | |
1706 | lp = find_lwp_pid (ptid); | |
9f0bdab8 | 1707 | gdb_assert (lp != NULL); |
d6b0e80f | 1708 | |
9f0bdab8 | 1709 | /* Remember if we're stepping. */ |
25289eb2 | 1710 | lp->last_resume_kind = step ? resume_step : resume_continue; |
d6b0e80f | 1711 | |
9f0bdab8 DJ |
1712 | /* If we have a pending wait status for this thread, there is no |
1713 | point in resuming the process. But first make sure that | |
1714 | linux_nat_wait won't preemptively handle the event - we | |
1715 | should never take this short-circuit if we are going to | |
1716 | leave LP running, since we have skipped resuming all the | |
1717 | other threads. This bit of code needs to be synchronized | |
1718 | with linux_nat_wait. */ | |
76f50ad1 | 1719 | |
9f0bdab8 DJ |
1720 | if (lp->status && WIFSTOPPED (lp->status)) |
1721 | { | |
2455069d UW |
1722 | if (!lp->step |
1723 | && WSTOPSIG (lp->status) | |
1724 | && sigismember (&pass_mask, WSTOPSIG (lp->status))) | |
d6b0e80f | 1725 | { |
9f0bdab8 DJ |
1726 | if (debug_linux_nat) |
1727 | fprintf_unfiltered (gdb_stdlog, | |
1728 | "LLR: Not short circuiting for ignored " | |
1729 | "status 0x%x\n", lp->status); | |
1730 | ||
d6b0e80f AC |
1731 | /* FIXME: What should we do if we are supposed to continue |
1732 | this thread with a signal? */ | |
a493e3e2 | 1733 | gdb_assert (signo == GDB_SIGNAL_0); |
2ea28649 | 1734 | signo = gdb_signal_from_host (WSTOPSIG (lp->status)); |
9f0bdab8 DJ |
1735 | lp->status = 0; |
1736 | } | |
1737 | } | |
76f50ad1 | 1738 | |
8a99810d | 1739 | if (lwp_status_pending_p (lp)) |
9f0bdab8 DJ |
1740 | { |
1741 | /* FIXME: What should we do if we are supposed to continue | |
1742 | this thread with a signal? */ | |
a493e3e2 | 1743 | gdb_assert (signo == GDB_SIGNAL_0); |
76f50ad1 | 1744 | |
9f0bdab8 DJ |
1745 | if (debug_linux_nat) |
1746 | fprintf_unfiltered (gdb_stdlog, | |
1747 | "LLR: Short circuiting for status 0x%x\n", | |
1748 | lp->status); | |
d6b0e80f | 1749 | |
7feb7d06 PA |
1750 | if (target_can_async_p ()) |
1751 | { | |
6a3753b3 | 1752 | target_async (1); |
7feb7d06 PA |
1753 | /* Tell the event loop we have something to process. */ |
1754 | async_file_mark (); | |
1755 | } | |
9f0bdab8 | 1756 | return; |
d6b0e80f AC |
1757 | } |
1758 | ||
d90e17a7 | 1759 | if (resume_many) |
d3a70e03 TT |
1760 | iterate_over_lwps (ptid, [=] (struct lwp_info *info) |
1761 | { | |
1762 | return linux_nat_resume_callback (info, lp); | |
1763 | }); | |
d90e17a7 | 1764 | |
d6b0e80f AC |
1765 | if (debug_linux_nat) |
1766 | fprintf_unfiltered (gdb_stdlog, | |
1767 | "LLR: %s %s, %s (resume event thread)\n", | |
1768 | step ? "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
a068643d | 1769 | target_pid_to_str (lp->ptid).c_str (), |
a493e3e2 | 1770 | (signo != GDB_SIGNAL_0 |
2ea28649 | 1771 | ? strsignal (gdb_signal_to_host (signo)) : "0")); |
b84876c2 | 1772 | |
2bf6fb9d PA |
1773 | linux_resume_one_lwp (lp, step, signo); |
1774 | ||
b84876c2 | 1775 | if (target_can_async_p ()) |
6a3753b3 | 1776 | target_async (1); |
d6b0e80f AC |
1777 | } |
1778 | ||
c5f62d5f | 1779 | /* Send a signal to an LWP. */ |
d6b0e80f AC |
1780 | |
1781 | static int | |
1782 | kill_lwp (int lwpid, int signo) | |
1783 | { | |
4a6ed09b | 1784 | int ret; |
d6b0e80f | 1785 | |
4a6ed09b PA |
1786 | errno = 0; |
1787 | ret = syscall (__NR_tkill, lwpid, signo); | |
1788 | if (errno == ENOSYS) | |
1789 | { | |
1790 | /* If tkill fails, then we are not using nptl threads, a | |
1791 | configuration we no longer support. */ | |
1792 | perror_with_name (("tkill")); | |
1793 | } | |
1794 | return ret; | |
d6b0e80f AC |
1795 | } |
1796 | ||
ca2163eb PA |
1797 | /* Handle a GNU/Linux syscall trap wait response. If we see a syscall |
1798 | event, check if the core is interested in it: if not, ignore the | |
1799 | event, and keep waiting; otherwise, we need to toggle the LWP's | |
1800 | syscall entry/exit status, since the ptrace event itself doesn't | |
1801 | indicate it, and report the trap to higher layers. */ | |
1802 | ||
1803 | static int | |
1804 | linux_handle_syscall_trap (struct lwp_info *lp, int stopping) | |
1805 | { | |
1806 | struct target_waitstatus *ourstatus = &lp->waitstatus; | |
1807 | struct gdbarch *gdbarch = target_thread_architecture (lp->ptid); | |
00431a78 PA |
1808 | thread_info *thread = find_thread_ptid (lp->ptid); |
1809 | int syscall_number = (int) gdbarch_get_syscall_number (gdbarch, thread); | |
ca2163eb PA |
1810 | |
1811 | if (stopping) | |
1812 | { | |
1813 | /* If we're stopping threads, there's a SIGSTOP pending, which | |
1814 | makes it so that the LWP reports an immediate syscall return, | |
1815 | followed by the SIGSTOP. Skip seeing that "return" using | |
1816 | PTRACE_CONT directly, and let stop_wait_callback collect the | |
1817 | SIGSTOP. Later when the thread is resumed, a new syscall | |
1818 | entry event. If we didn't do this (and returned 0), we'd | |
1819 | leave a syscall entry pending, and our caller, by using | |
1820 | PTRACE_CONT to collect the SIGSTOP, skips the syscall return | |
1821 | itself. Later, when the user re-resumes this LWP, we'd see | |
1822 | another syscall entry event and we'd mistake it for a return. | |
1823 | ||
1824 | If stop_wait_callback didn't force the SIGSTOP out of the LWP | |
1825 | (leaving immediately with LWP->signalled set, without issuing | |
1826 | a PTRACE_CONT), it would still be problematic to leave this | |
1827 | syscall enter pending, as later when the thread is resumed, | |
1828 | it would then see the same syscall exit mentioned above, | |
1829 | followed by the delayed SIGSTOP, while the syscall didn't | |
1830 | actually get to execute. It seems it would be even more | |
1831 | confusing to the user. */ | |
1832 | ||
1833 | if (debug_linux_nat) | |
1834 | fprintf_unfiltered (gdb_stdlog, | |
1835 | "LHST: ignoring syscall %d " | |
1836 | "for LWP %ld (stopping threads), " | |
1837 | "resuming with PTRACE_CONT for SIGSTOP\n", | |
1838 | syscall_number, | |
e38504b3 | 1839 | lp->ptid.lwp ()); |
ca2163eb PA |
1840 | |
1841 | lp->syscall_state = TARGET_WAITKIND_IGNORE; | |
e38504b3 | 1842 | ptrace (PTRACE_CONT, lp->ptid.lwp (), 0, 0); |
8817a6f2 | 1843 | lp->stopped = 0; |
ca2163eb PA |
1844 | return 1; |
1845 | } | |
1846 | ||
bfd09d20 JS |
1847 | /* Always update the entry/return state, even if this particular |
1848 | syscall isn't interesting to the core now. In async mode, | |
1849 | the user could install a new catchpoint for this syscall | |
1850 | between syscall enter/return, and we'll need to know to | |
1851 | report a syscall return if that happens. */ | |
1852 | lp->syscall_state = (lp->syscall_state == TARGET_WAITKIND_SYSCALL_ENTRY | |
1853 | ? TARGET_WAITKIND_SYSCALL_RETURN | |
1854 | : TARGET_WAITKIND_SYSCALL_ENTRY); | |
1855 | ||
ca2163eb PA |
1856 | if (catch_syscall_enabled ()) |
1857 | { | |
ca2163eb PA |
1858 | if (catching_syscall_number (syscall_number)) |
1859 | { | |
1860 | /* Alright, an event to report. */ | |
1861 | ourstatus->kind = lp->syscall_state; | |
1862 | ourstatus->value.syscall_number = syscall_number; | |
1863 | ||
1864 | if (debug_linux_nat) | |
1865 | fprintf_unfiltered (gdb_stdlog, | |
1866 | "LHST: stopping for %s of syscall %d" | |
1867 | " for LWP %ld\n", | |
3e43a32a MS |
1868 | lp->syscall_state |
1869 | == TARGET_WAITKIND_SYSCALL_ENTRY | |
ca2163eb PA |
1870 | ? "entry" : "return", |
1871 | syscall_number, | |
e38504b3 | 1872 | lp->ptid.lwp ()); |
ca2163eb PA |
1873 | return 0; |
1874 | } | |
1875 | ||
1876 | if (debug_linux_nat) | |
1877 | fprintf_unfiltered (gdb_stdlog, | |
1878 | "LHST: ignoring %s of syscall %d " | |
1879 | "for LWP %ld\n", | |
1880 | lp->syscall_state == TARGET_WAITKIND_SYSCALL_ENTRY | |
1881 | ? "entry" : "return", | |
1882 | syscall_number, | |
e38504b3 | 1883 | lp->ptid.lwp ()); |
ca2163eb PA |
1884 | } |
1885 | else | |
1886 | { | |
1887 | /* If we had been syscall tracing, and hence used PT_SYSCALL | |
1888 | before on this LWP, it could happen that the user removes all | |
1889 | syscall catchpoints before we get to process this event. | |
1890 | There are two noteworthy issues here: | |
1891 | ||
1892 | - When stopped at a syscall entry event, resuming with | |
1893 | PT_STEP still resumes executing the syscall and reports a | |
1894 | syscall return. | |
1895 | ||
1896 | - Only PT_SYSCALL catches syscall enters. If we last | |
1897 | single-stepped this thread, then this event can't be a | |
1898 | syscall enter. If we last single-stepped this thread, this | |
1899 | has to be a syscall exit. | |
1900 | ||
1901 | The points above mean that the next resume, be it PT_STEP or | |
1902 | PT_CONTINUE, can not trigger a syscall trace event. */ | |
1903 | if (debug_linux_nat) | |
1904 | fprintf_unfiltered (gdb_stdlog, | |
3e43a32a MS |
1905 | "LHST: caught syscall event " |
1906 | "with no syscall catchpoints." | |
ca2163eb PA |
1907 | " %d for LWP %ld, ignoring\n", |
1908 | syscall_number, | |
e38504b3 | 1909 | lp->ptid.lwp ()); |
ca2163eb PA |
1910 | lp->syscall_state = TARGET_WAITKIND_IGNORE; |
1911 | } | |
1912 | ||
1913 | /* The core isn't interested in this event. For efficiency, avoid | |
1914 | stopping all threads only to have the core resume them all again. | |
1915 | Since we're not stopping threads, if we're still syscall tracing | |
1916 | and not stepping, we can't use PTRACE_CONT here, as we'd miss any | |
1917 | subsequent syscall. Simply resume using the inf-ptrace layer, | |
1918 | which knows when to use PT_SYSCALL or PT_CONTINUE. */ | |
1919 | ||
8a99810d | 1920 | linux_resume_one_lwp (lp, lp->step, GDB_SIGNAL_0); |
ca2163eb PA |
1921 | return 1; |
1922 | } | |
1923 | ||
3d799a95 DJ |
1924 | /* Handle a GNU/Linux extended wait response. If we see a clone |
1925 | event, we need to add the new LWP to our list (and not report the | |
1926 | trap to higher layers). This function returns non-zero if the | |
1927 | event should be ignored and we should wait again. If STOPPING is | |
1928 | true, the new LWP remains stopped, otherwise it is continued. */ | |
d6b0e80f AC |
1929 | |
1930 | static int | |
4dd63d48 | 1931 | linux_handle_extended_wait (struct lwp_info *lp, int status) |
d6b0e80f | 1932 | { |
e38504b3 | 1933 | int pid = lp->ptid.lwp (); |
3d799a95 | 1934 | struct target_waitstatus *ourstatus = &lp->waitstatus; |
89a5711c | 1935 | int event = linux_ptrace_get_extended_event (status); |
d6b0e80f | 1936 | |
bfd09d20 JS |
1937 | /* All extended events we currently use are mid-syscall. Only |
1938 | PTRACE_EVENT_STOP is delivered more like a signal-stop, but | |
1939 | you have to be using PTRACE_SEIZE to get that. */ | |
1940 | lp->syscall_state = TARGET_WAITKIND_SYSCALL_ENTRY; | |
1941 | ||
3d799a95 DJ |
1942 | if (event == PTRACE_EVENT_FORK || event == PTRACE_EVENT_VFORK |
1943 | || event == PTRACE_EVENT_CLONE) | |
d6b0e80f | 1944 | { |
3d799a95 DJ |
1945 | unsigned long new_pid; |
1946 | int ret; | |
1947 | ||
1948 | ptrace (PTRACE_GETEVENTMSG, pid, 0, &new_pid); | |
6fc19103 | 1949 | |
3d799a95 DJ |
1950 | /* If we haven't already seen the new PID stop, wait for it now. */ |
1951 | if (! pull_pid_from_list (&stopped_pids, new_pid, &status)) | |
1952 | { | |
1953 | /* The new child has a pending SIGSTOP. We can't affect it until it | |
1954 | hits the SIGSTOP, but we're already attached. */ | |
4a6ed09b | 1955 | ret = my_waitpid (new_pid, &status, __WALL); |
3d799a95 DJ |
1956 | if (ret == -1) |
1957 | perror_with_name (_("waiting for new child")); | |
1958 | else if (ret != new_pid) | |
1959 | internal_error (__FILE__, __LINE__, | |
1960 | _("wait returned unexpected PID %d"), ret); | |
1961 | else if (!WIFSTOPPED (status)) | |
1962 | internal_error (__FILE__, __LINE__, | |
1963 | _("wait returned unexpected status 0x%x"), status); | |
1964 | } | |
1965 | ||
fd79271b | 1966 | ourstatus->value.related_pid = ptid_t (new_pid, new_pid, 0); |
3d799a95 | 1967 | |
26cb8b7c PA |
1968 | if (event == PTRACE_EVENT_FORK || event == PTRACE_EVENT_VFORK) |
1969 | { | |
1970 | /* The arch-specific native code may need to know about new | |
1971 | forks even if those end up never mapped to an | |
1972 | inferior. */ | |
135340af | 1973 | linux_target->low_new_fork (lp, new_pid); |
26cb8b7c PA |
1974 | } |
1975 | ||
2277426b | 1976 | if (event == PTRACE_EVENT_FORK |
e99b03dc | 1977 | && linux_fork_checkpointing_p (lp->ptid.pid ())) |
2277426b | 1978 | { |
2277426b PA |
1979 | /* Handle checkpointing by linux-fork.c here as a special |
1980 | case. We don't want the follow-fork-mode or 'catch fork' | |
1981 | to interfere with this. */ | |
1982 | ||
1983 | /* This won't actually modify the breakpoint list, but will | |
1984 | physically remove the breakpoints from the child. */ | |
fd79271b | 1985 | detach_breakpoints (ptid_t (new_pid, new_pid, 0)); |
2277426b PA |
1986 | |
1987 | /* Retain child fork in ptrace (stopped) state. */ | |
14571dad MS |
1988 | if (!find_fork_pid (new_pid)) |
1989 | add_fork (new_pid); | |
2277426b PA |
1990 | |
1991 | /* Report as spurious, so that infrun doesn't want to follow | |
1992 | this fork. We're actually doing an infcall in | |
1993 | linux-fork.c. */ | |
1994 | ourstatus->kind = TARGET_WAITKIND_SPURIOUS; | |
2277426b PA |
1995 | |
1996 | /* Report the stop to the core. */ | |
1997 | return 0; | |
1998 | } | |
1999 | ||
3d799a95 DJ |
2000 | if (event == PTRACE_EVENT_FORK) |
2001 | ourstatus->kind = TARGET_WAITKIND_FORKED; | |
2002 | else if (event == PTRACE_EVENT_VFORK) | |
2003 | ourstatus->kind = TARGET_WAITKIND_VFORKED; | |
4dd63d48 | 2004 | else if (event == PTRACE_EVENT_CLONE) |
3d799a95 | 2005 | { |
78768c4a JK |
2006 | struct lwp_info *new_lp; |
2007 | ||
3d799a95 | 2008 | ourstatus->kind = TARGET_WAITKIND_IGNORE; |
78768c4a | 2009 | |
3c4d7e12 PA |
2010 | if (debug_linux_nat) |
2011 | fprintf_unfiltered (gdb_stdlog, | |
2012 | "LHEW: Got clone event " | |
2013 | "from LWP %d, new child is LWP %ld\n", | |
2014 | pid, new_pid); | |
2015 | ||
e99b03dc | 2016 | new_lp = add_lwp (ptid_t (lp->ptid.pid (), new_pid, 0)); |
4c28f408 | 2017 | new_lp->stopped = 1; |
4dd63d48 | 2018 | new_lp->resumed = 1; |
d6b0e80f | 2019 | |
2db9a427 PA |
2020 | /* If the thread_db layer is active, let it record the user |
2021 | level thread id and status, and add the thread to GDB's | |
2022 | list. */ | |
2023 | if (!thread_db_notice_clone (lp->ptid, new_lp->ptid)) | |
3d799a95 | 2024 | { |
2db9a427 PA |
2025 | /* The process is not using thread_db. Add the LWP to |
2026 | GDB's list. */ | |
e38504b3 | 2027 | target_post_attach (new_lp->ptid.lwp ()); |
2db9a427 PA |
2028 | add_thread (new_lp->ptid); |
2029 | } | |
4c28f408 | 2030 | |
2ee52aa4 | 2031 | /* Even if we're stopping the thread for some reason |
4dd63d48 PA |
2032 | internal to this module, from the perspective of infrun |
2033 | and the user/frontend, this new thread is running until | |
2034 | it next reports a stop. */ | |
2ee52aa4 | 2035 | set_running (new_lp->ptid, 1); |
4dd63d48 | 2036 | set_executing (new_lp->ptid, 1); |
4c28f408 | 2037 | |
4dd63d48 | 2038 | if (WSTOPSIG (status) != SIGSTOP) |
79395f92 | 2039 | { |
4dd63d48 PA |
2040 | /* This can happen if someone starts sending signals to |
2041 | the new thread before it gets a chance to run, which | |
2042 | have a lower number than SIGSTOP (e.g. SIGUSR1). | |
2043 | This is an unlikely case, and harder to handle for | |
2044 | fork / vfork than for clone, so we do not try - but | |
2045 | we handle it for clone events here. */ | |
2046 | ||
2047 | new_lp->signalled = 1; | |
2048 | ||
79395f92 PA |
2049 | /* We created NEW_LP so it cannot yet contain STATUS. */ |
2050 | gdb_assert (new_lp->status == 0); | |
2051 | ||
2052 | /* Save the wait status to report later. */ | |
2053 | if (debug_linux_nat) | |
2054 | fprintf_unfiltered (gdb_stdlog, | |
2055 | "LHEW: waitpid of new LWP %ld, " | |
2056 | "saving status %s\n", | |
e38504b3 | 2057 | (long) new_lp->ptid.lwp (), |
79395f92 PA |
2058 | status_to_str (status)); |
2059 | new_lp->status = status; | |
2060 | } | |
aa01bd36 PA |
2061 | else if (report_thread_events) |
2062 | { | |
2063 | new_lp->waitstatus.kind = TARGET_WAITKIND_THREAD_CREATED; | |
2064 | new_lp->status = status; | |
2065 | } | |
79395f92 | 2066 | |
3d799a95 DJ |
2067 | return 1; |
2068 | } | |
2069 | ||
2070 | return 0; | |
d6b0e80f AC |
2071 | } |
2072 | ||
3d799a95 DJ |
2073 | if (event == PTRACE_EVENT_EXEC) |
2074 | { | |
a75724bc PA |
2075 | if (debug_linux_nat) |
2076 | fprintf_unfiltered (gdb_stdlog, | |
2077 | "LHEW: Got exec event from LWP %ld\n", | |
e38504b3 | 2078 | lp->ptid.lwp ()); |
a75724bc | 2079 | |
3d799a95 DJ |
2080 | ourstatus->kind = TARGET_WAITKIND_EXECD; |
2081 | ourstatus->value.execd_pathname | |
f6ac5f3d | 2082 | = xstrdup (linux_proc_pid_to_exec_file (pid)); |
3d799a95 | 2083 | |
8af756ef PA |
2084 | /* The thread that execed must have been resumed, but, when a |
2085 | thread execs, it changes its tid to the tgid, and the old | |
2086 | tgid thread might have not been resumed. */ | |
2087 | lp->resumed = 1; | |
6c95b8df PA |
2088 | return 0; |
2089 | } | |
2090 | ||
2091 | if (event == PTRACE_EVENT_VFORK_DONE) | |
2092 | { | |
2093 | if (current_inferior ()->waiting_for_vfork_done) | |
3d799a95 | 2094 | { |
6c95b8df | 2095 | if (debug_linux_nat) |
3e43a32a MS |
2096 | fprintf_unfiltered (gdb_stdlog, |
2097 | "LHEW: Got expected PTRACE_EVENT_" | |
2098 | "VFORK_DONE from LWP %ld: stopping\n", | |
e38504b3 | 2099 | lp->ptid.lwp ()); |
3d799a95 | 2100 | |
6c95b8df PA |
2101 | ourstatus->kind = TARGET_WAITKIND_VFORK_DONE; |
2102 | return 0; | |
3d799a95 DJ |
2103 | } |
2104 | ||
6c95b8df | 2105 | if (debug_linux_nat) |
3e43a32a MS |
2106 | fprintf_unfiltered (gdb_stdlog, |
2107 | "LHEW: Got PTRACE_EVENT_VFORK_DONE " | |
20ba1ce6 | 2108 | "from LWP %ld: ignoring\n", |
e38504b3 | 2109 | lp->ptid.lwp ()); |
6c95b8df | 2110 | return 1; |
3d799a95 DJ |
2111 | } |
2112 | ||
2113 | internal_error (__FILE__, __LINE__, | |
2114 | _("unknown ptrace event %d"), event); | |
d6b0e80f AC |
2115 | } |
2116 | ||
9c3a5d93 PA |
2117 | /* Suspend waiting for a signal. We're mostly interested in |
2118 | SIGCHLD/SIGINT. */ | |
2119 | ||
2120 | static void | |
2121 | wait_for_signal () | |
2122 | { | |
2123 | if (debug_linux_nat) | |
2124 | fprintf_unfiltered (gdb_stdlog, "linux-nat: about to sigsuspend\n"); | |
2125 | sigsuspend (&suspend_mask); | |
2126 | ||
2127 | /* If the quit flag is set, it means that the user pressed Ctrl-C | |
2128 | and we're debugging a process that is running on a separate | |
2129 | terminal, so we must forward the Ctrl-C to the inferior. (If the | |
2130 | inferior is sharing GDB's terminal, then the Ctrl-C reaches the | |
2131 | inferior directly.) We must do this here because functions that | |
2132 | need to block waiting for a signal loop forever until there's an | |
2133 | event to report before returning back to the event loop. */ | |
2134 | if (!target_terminal::is_ours ()) | |
2135 | { | |
2136 | if (check_quit_flag ()) | |
2137 | target_pass_ctrlc (); | |
2138 | } | |
2139 | } | |
2140 | ||
d6b0e80f AC |
2141 | /* Wait for LP to stop. Returns the wait status, or 0 if the LWP has |
2142 | exited. */ | |
2143 | ||
2144 | static int | |
2145 | wait_lwp (struct lwp_info *lp) | |
2146 | { | |
2147 | pid_t pid; | |
432b4d03 | 2148 | int status = 0; |
d6b0e80f | 2149 | int thread_dead = 0; |
432b4d03 | 2150 | sigset_t prev_mask; |
d6b0e80f AC |
2151 | |
2152 | gdb_assert (!lp->stopped); | |
2153 | gdb_assert (lp->status == 0); | |
2154 | ||
432b4d03 JK |
2155 | /* Make sure SIGCHLD is blocked for sigsuspend avoiding a race below. */ |
2156 | block_child_signals (&prev_mask); | |
2157 | ||
2158 | for (;;) | |
d6b0e80f | 2159 | { |
e38504b3 | 2160 | pid = my_waitpid (lp->ptid.lwp (), &status, __WALL | WNOHANG); |
a9f4bb21 PA |
2161 | if (pid == -1 && errno == ECHILD) |
2162 | { | |
2163 | /* The thread has previously exited. We need to delete it | |
4a6ed09b PA |
2164 | now because if this was a non-leader thread execing, we |
2165 | won't get an exit event. See comments on exec events at | |
2166 | the top of the file. */ | |
a9f4bb21 PA |
2167 | thread_dead = 1; |
2168 | if (debug_linux_nat) | |
2169 | fprintf_unfiltered (gdb_stdlog, "WL: %s vanished.\n", | |
a068643d | 2170 | target_pid_to_str (lp->ptid).c_str ()); |
a9f4bb21 | 2171 | } |
432b4d03 JK |
2172 | if (pid != 0) |
2173 | break; | |
2174 | ||
2175 | /* Bugs 10970, 12702. | |
2176 | Thread group leader may have exited in which case we'll lock up in | |
2177 | waitpid if there are other threads, even if they are all zombies too. | |
2178 | Basically, we're not supposed to use waitpid this way. | |
4a6ed09b PA |
2179 | tkill(pid,0) cannot be used here as it gets ESRCH for both |
2180 | for zombie and running processes. | |
432b4d03 JK |
2181 | |
2182 | As a workaround, check if we're waiting for the thread group leader and | |
2183 | if it's a zombie, and avoid calling waitpid if it is. | |
2184 | ||
2185 | This is racy, what if the tgl becomes a zombie right after we check? | |
2186 | Therefore always use WNOHANG with sigsuspend - it is equivalent to | |
5f572dec | 2187 | waiting waitpid but linux_proc_pid_is_zombie is safe this way. */ |
432b4d03 | 2188 | |
e38504b3 TT |
2189 | if (lp->ptid.pid () == lp->ptid.lwp () |
2190 | && linux_proc_pid_is_zombie (lp->ptid.lwp ())) | |
d6b0e80f | 2191 | { |
d6b0e80f AC |
2192 | thread_dead = 1; |
2193 | if (debug_linux_nat) | |
432b4d03 JK |
2194 | fprintf_unfiltered (gdb_stdlog, |
2195 | "WL: Thread group leader %s vanished.\n", | |
a068643d | 2196 | target_pid_to_str (lp->ptid).c_str ()); |
432b4d03 | 2197 | break; |
d6b0e80f | 2198 | } |
432b4d03 JK |
2199 | |
2200 | /* Wait for next SIGCHLD and try again. This may let SIGCHLD handlers | |
2201 | get invoked despite our caller had them intentionally blocked by | |
2202 | block_child_signals. This is sensitive only to the loop of | |
2203 | linux_nat_wait_1 and there if we get called my_waitpid gets called | |
2204 | again before it gets to sigsuspend so we can safely let the handlers | |
2205 | get executed here. */ | |
9c3a5d93 | 2206 | wait_for_signal (); |
432b4d03 JK |
2207 | } |
2208 | ||
2209 | restore_child_signals_mask (&prev_mask); | |
2210 | ||
d6b0e80f AC |
2211 | if (!thread_dead) |
2212 | { | |
e38504b3 | 2213 | gdb_assert (pid == lp->ptid.lwp ()); |
d6b0e80f AC |
2214 | |
2215 | if (debug_linux_nat) | |
2216 | { | |
2217 | fprintf_unfiltered (gdb_stdlog, | |
2218 | "WL: waitpid %s received %s\n", | |
a068643d | 2219 | target_pid_to_str (lp->ptid).c_str (), |
d6b0e80f AC |
2220 | status_to_str (status)); |
2221 | } | |
d6b0e80f | 2222 | |
a9f4bb21 PA |
2223 | /* Check if the thread has exited. */ |
2224 | if (WIFEXITED (status) || WIFSIGNALED (status)) | |
2225 | { | |
aa01bd36 | 2226 | if (report_thread_events |
e38504b3 | 2227 | || lp->ptid.pid () == lp->ptid.lwp ()) |
69dde7dc PA |
2228 | { |
2229 | if (debug_linux_nat) | |
aa01bd36 | 2230 | fprintf_unfiltered (gdb_stdlog, "WL: LWP %d exited.\n", |
e99b03dc | 2231 | lp->ptid.pid ()); |
69dde7dc | 2232 | |
aa01bd36 | 2233 | /* If this is the leader exiting, it means the whole |
69dde7dc PA |
2234 | process is gone. Store the status to report to the |
2235 | core. Store it in lp->waitstatus, because lp->status | |
2236 | would be ambiguous (W_EXITCODE(0,0) == 0). */ | |
2237 | store_waitstatus (&lp->waitstatus, status); | |
2238 | return 0; | |
2239 | } | |
2240 | ||
a9f4bb21 PA |
2241 | thread_dead = 1; |
2242 | if (debug_linux_nat) | |
2243 | fprintf_unfiltered (gdb_stdlog, "WL: %s exited.\n", | |
a068643d | 2244 | target_pid_to_str (lp->ptid).c_str ()); |
a9f4bb21 | 2245 | } |
d6b0e80f AC |
2246 | } |
2247 | ||
2248 | if (thread_dead) | |
2249 | { | |
e26af52f | 2250 | exit_lwp (lp); |
d6b0e80f AC |
2251 | return 0; |
2252 | } | |
2253 | ||
2254 | gdb_assert (WIFSTOPPED (status)); | |
8817a6f2 | 2255 | lp->stopped = 1; |
d6b0e80f | 2256 | |
8784d563 PA |
2257 | if (lp->must_set_ptrace_flags) |
2258 | { | |
e99b03dc | 2259 | struct inferior *inf = find_inferior_pid (lp->ptid.pid ()); |
de0d863e | 2260 | int options = linux_nat_ptrace_options (inf->attach_flag); |
8784d563 | 2261 | |
e38504b3 | 2262 | linux_enable_event_reporting (lp->ptid.lwp (), options); |
8784d563 PA |
2263 | lp->must_set_ptrace_flags = 0; |
2264 | } | |
2265 | ||
ca2163eb PA |
2266 | /* Handle GNU/Linux's syscall SIGTRAPs. */ |
2267 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SYSCALL_SIGTRAP) | |
2268 | { | |
2269 | /* No longer need the sysgood bit. The ptrace event ends up | |
2270 | recorded in lp->waitstatus if we care for it. We can carry | |
2271 | on handling the event like a regular SIGTRAP from here | |
2272 | on. */ | |
2273 | status = W_STOPCODE (SIGTRAP); | |
2274 | if (linux_handle_syscall_trap (lp, 1)) | |
2275 | return wait_lwp (lp); | |
2276 | } | |
bfd09d20 JS |
2277 | else |
2278 | { | |
2279 | /* Almost all other ptrace-stops are known to be outside of system | |
2280 | calls, with further exceptions in linux_handle_extended_wait. */ | |
2281 | lp->syscall_state = TARGET_WAITKIND_IGNORE; | |
2282 | } | |
ca2163eb | 2283 | |
d6b0e80f | 2284 | /* Handle GNU/Linux's extended waitstatus for trace events. */ |
89a5711c DB |
2285 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP |
2286 | && linux_is_extended_waitstatus (status)) | |
d6b0e80f AC |
2287 | { |
2288 | if (debug_linux_nat) | |
2289 | fprintf_unfiltered (gdb_stdlog, | |
2290 | "WL: Handling extended status 0x%06x\n", | |
2291 | status); | |
4dd63d48 | 2292 | linux_handle_extended_wait (lp, status); |
20ba1ce6 | 2293 | return 0; |
d6b0e80f AC |
2294 | } |
2295 | ||
2296 | return status; | |
2297 | } | |
2298 | ||
2299 | /* Send a SIGSTOP to LP. */ | |
2300 | ||
2301 | static int | |
d3a70e03 | 2302 | stop_callback (struct lwp_info *lp) |
d6b0e80f AC |
2303 | { |
2304 | if (!lp->stopped && !lp->signalled) | |
2305 | { | |
2306 | int ret; | |
2307 | ||
2308 | if (debug_linux_nat) | |
2309 | { | |
2310 | fprintf_unfiltered (gdb_stdlog, | |
2311 | "SC: kill %s **<SIGSTOP>**\n", | |
a068643d | 2312 | target_pid_to_str (lp->ptid).c_str ()); |
d6b0e80f AC |
2313 | } |
2314 | errno = 0; | |
e38504b3 | 2315 | ret = kill_lwp (lp->ptid.lwp (), SIGSTOP); |
d6b0e80f AC |
2316 | if (debug_linux_nat) |
2317 | { | |
2318 | fprintf_unfiltered (gdb_stdlog, | |
2319 | "SC: lwp kill %d %s\n", | |
2320 | ret, | |
2321 | errno ? safe_strerror (errno) : "ERRNO-OK"); | |
2322 | } | |
2323 | ||
2324 | lp->signalled = 1; | |
2325 | gdb_assert (lp->status == 0); | |
2326 | } | |
2327 | ||
2328 | return 0; | |
2329 | } | |
2330 | ||
7b50312a PA |
2331 | /* Request a stop on LWP. */ |
2332 | ||
2333 | void | |
2334 | linux_stop_lwp (struct lwp_info *lwp) | |
2335 | { | |
d3a70e03 | 2336 | stop_callback (lwp); |
7b50312a PA |
2337 | } |
2338 | ||
2db9a427 PA |
2339 | /* See linux-nat.h */ |
2340 | ||
2341 | void | |
2342 | linux_stop_and_wait_all_lwps (void) | |
2343 | { | |
2344 | /* Stop all LWP's ... */ | |
d3a70e03 | 2345 | iterate_over_lwps (minus_one_ptid, stop_callback); |
2db9a427 PA |
2346 | |
2347 | /* ... and wait until all of them have reported back that | |
2348 | they're no longer running. */ | |
d3a70e03 | 2349 | iterate_over_lwps (minus_one_ptid, stop_wait_callback); |
2db9a427 PA |
2350 | } |
2351 | ||
2352 | /* See linux-nat.h */ | |
2353 | ||
2354 | void | |
2355 | linux_unstop_all_lwps (void) | |
2356 | { | |
2357 | iterate_over_lwps (minus_one_ptid, | |
d3a70e03 TT |
2358 | [] (struct lwp_info *info) |
2359 | { | |
2360 | return resume_stopped_resumed_lwps (info, minus_one_ptid); | |
2361 | }); | |
2db9a427 PA |
2362 | } |
2363 | ||
57380f4e | 2364 | /* Return non-zero if LWP PID has a pending SIGINT. */ |
d6b0e80f AC |
2365 | |
2366 | static int | |
57380f4e DJ |
2367 | linux_nat_has_pending_sigint (int pid) |
2368 | { | |
2369 | sigset_t pending, blocked, ignored; | |
57380f4e DJ |
2370 | |
2371 | linux_proc_pending_signals (pid, &pending, &blocked, &ignored); | |
2372 | ||
2373 | if (sigismember (&pending, SIGINT) | |
2374 | && !sigismember (&ignored, SIGINT)) | |
2375 | return 1; | |
2376 | ||
2377 | return 0; | |
2378 | } | |
2379 | ||
2380 | /* Set a flag in LP indicating that we should ignore its next SIGINT. */ | |
2381 | ||
2382 | static int | |
d3a70e03 | 2383 | set_ignore_sigint (struct lwp_info *lp) |
d6b0e80f | 2384 | { |
57380f4e DJ |
2385 | /* If a thread has a pending SIGINT, consume it; otherwise, set a |
2386 | flag to consume the next one. */ | |
2387 | if (lp->stopped && lp->status != 0 && WIFSTOPPED (lp->status) | |
2388 | && WSTOPSIG (lp->status) == SIGINT) | |
2389 | lp->status = 0; | |
2390 | else | |
2391 | lp->ignore_sigint = 1; | |
2392 | ||
2393 | return 0; | |
2394 | } | |
2395 | ||
2396 | /* If LP does not have a SIGINT pending, then clear the ignore_sigint flag. | |
2397 | This function is called after we know the LWP has stopped; if the LWP | |
2398 | stopped before the expected SIGINT was delivered, then it will never have | |
2399 | arrived. Also, if the signal was delivered to a shared queue and consumed | |
2400 | by a different thread, it will never be delivered to this LWP. */ | |
d6b0e80f | 2401 | |
57380f4e DJ |
2402 | static void |
2403 | maybe_clear_ignore_sigint (struct lwp_info *lp) | |
2404 | { | |
2405 | if (!lp->ignore_sigint) | |
2406 | return; | |
2407 | ||
e38504b3 | 2408 | if (!linux_nat_has_pending_sigint (lp->ptid.lwp ())) |
57380f4e DJ |
2409 | { |
2410 | if (debug_linux_nat) | |
2411 | fprintf_unfiltered (gdb_stdlog, | |
2412 | "MCIS: Clearing bogus flag for %s\n", | |
a068643d | 2413 | target_pid_to_str (lp->ptid).c_str ()); |
57380f4e DJ |
2414 | lp->ignore_sigint = 0; |
2415 | } | |
2416 | } | |
2417 | ||
ebec9a0f PA |
2418 | /* Fetch the possible triggered data watchpoint info and store it in |
2419 | LP. | |
2420 | ||
2421 | On some archs, like x86, that use debug registers to set | |
2422 | watchpoints, it's possible that the way to know which watched | |
2423 | address trapped, is to check the register that is used to select | |
2424 | which address to watch. Problem is, between setting the watchpoint | |
2425 | and reading back which data address trapped, the user may change | |
2426 | the set of watchpoints, and, as a consequence, GDB changes the | |
2427 | debug registers in the inferior. To avoid reading back a stale | |
2428 | stopped-data-address when that happens, we cache in LP the fact | |
2429 | that a watchpoint trapped, and the corresponding data address, as | |
2430 | soon as we see LP stop with a SIGTRAP. If GDB changes the debug | |
2431 | registers meanwhile, we have the cached data we can rely on. */ | |
2432 | ||
9c02b525 PA |
2433 | static int |
2434 | check_stopped_by_watchpoint (struct lwp_info *lp) | |
ebec9a0f | 2435 | { |
2989a365 | 2436 | scoped_restore save_inferior_ptid = make_scoped_restore (&inferior_ptid); |
ebec9a0f PA |
2437 | inferior_ptid = lp->ptid; |
2438 | ||
f6ac5f3d | 2439 | if (linux_target->low_stopped_by_watchpoint ()) |
ebec9a0f | 2440 | { |
15c66dd6 | 2441 | lp->stop_reason = TARGET_STOPPED_BY_WATCHPOINT; |
f6ac5f3d PA |
2442 | lp->stopped_data_address_p |
2443 | = linux_target->low_stopped_data_address (&lp->stopped_data_address); | |
ebec9a0f PA |
2444 | } |
2445 | ||
15c66dd6 | 2446 | return lp->stop_reason == TARGET_STOPPED_BY_WATCHPOINT; |
9c02b525 PA |
2447 | } |
2448 | ||
9c02b525 | 2449 | /* Returns true if the LWP had stopped for a watchpoint. */ |
ebec9a0f | 2450 | |
57810aa7 | 2451 | bool |
f6ac5f3d | 2452 | linux_nat_target::stopped_by_watchpoint () |
ebec9a0f PA |
2453 | { |
2454 | struct lwp_info *lp = find_lwp_pid (inferior_ptid); | |
2455 | ||
2456 | gdb_assert (lp != NULL); | |
2457 | ||
15c66dd6 | 2458 | return lp->stop_reason == TARGET_STOPPED_BY_WATCHPOINT; |
ebec9a0f PA |
2459 | } |
2460 | ||
57810aa7 | 2461 | bool |
f6ac5f3d | 2462 | linux_nat_target::stopped_data_address (CORE_ADDR *addr_p) |
ebec9a0f PA |
2463 | { |
2464 | struct lwp_info *lp = find_lwp_pid (inferior_ptid); | |
2465 | ||
2466 | gdb_assert (lp != NULL); | |
2467 | ||
2468 | *addr_p = lp->stopped_data_address; | |
2469 | ||
2470 | return lp->stopped_data_address_p; | |
2471 | } | |
2472 | ||
26ab7092 JK |
2473 | /* Commonly any breakpoint / watchpoint generate only SIGTRAP. */ |
2474 | ||
135340af PA |
2475 | bool |
2476 | linux_nat_target::low_status_is_event (int status) | |
26ab7092 JK |
2477 | { |
2478 | return WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP; | |
2479 | } | |
2480 | ||
57380f4e DJ |
2481 | /* Wait until LP is stopped. */ |
2482 | ||
2483 | static int | |
d3a70e03 | 2484 | stop_wait_callback (struct lwp_info *lp) |
57380f4e | 2485 | { |
c9657e70 | 2486 | struct inferior *inf = find_inferior_ptid (lp->ptid); |
6c95b8df PA |
2487 | |
2488 | /* If this is a vfork parent, bail out, it is not going to report | |
2489 | any SIGSTOP until the vfork is done with. */ | |
2490 | if (inf->vfork_child != NULL) | |
2491 | return 0; | |
2492 | ||
d6b0e80f AC |
2493 | if (!lp->stopped) |
2494 | { | |
2495 | int status; | |
2496 | ||
2497 | status = wait_lwp (lp); | |
2498 | if (status == 0) | |
2499 | return 0; | |
2500 | ||
57380f4e DJ |
2501 | if (lp->ignore_sigint && WIFSTOPPED (status) |
2502 | && WSTOPSIG (status) == SIGINT) | |
d6b0e80f | 2503 | { |
57380f4e | 2504 | lp->ignore_sigint = 0; |
d6b0e80f AC |
2505 | |
2506 | errno = 0; | |
e38504b3 | 2507 | ptrace (PTRACE_CONT, lp->ptid.lwp (), 0, 0); |
8817a6f2 | 2508 | lp->stopped = 0; |
d6b0e80f AC |
2509 | if (debug_linux_nat) |
2510 | fprintf_unfiltered (gdb_stdlog, | |
3e43a32a MS |
2511 | "PTRACE_CONT %s, 0, 0 (%s) " |
2512 | "(discarding SIGINT)\n", | |
a068643d | 2513 | target_pid_to_str (lp->ptid).c_str (), |
d6b0e80f AC |
2514 | errno ? safe_strerror (errno) : "OK"); |
2515 | ||
d3a70e03 | 2516 | return stop_wait_callback (lp); |
d6b0e80f AC |
2517 | } |
2518 | ||
57380f4e DJ |
2519 | maybe_clear_ignore_sigint (lp); |
2520 | ||
d6b0e80f AC |
2521 | if (WSTOPSIG (status) != SIGSTOP) |
2522 | { | |
e5ef252a | 2523 | /* The thread was stopped with a signal other than SIGSTOP. */ |
7feb7d06 | 2524 | |
e5ef252a PA |
2525 | if (debug_linux_nat) |
2526 | fprintf_unfiltered (gdb_stdlog, | |
2527 | "SWC: Pending event %s in %s\n", | |
2528 | status_to_str ((int) status), | |
a068643d | 2529 | target_pid_to_str (lp->ptid).c_str ()); |
e5ef252a PA |
2530 | |
2531 | /* Save the sigtrap event. */ | |
2532 | lp->status = status; | |
e5ef252a | 2533 | gdb_assert (lp->signalled); |
e7ad2f14 | 2534 | save_stop_reason (lp); |
d6b0e80f AC |
2535 | } |
2536 | else | |
2537 | { | |
7010835a | 2538 | /* We caught the SIGSTOP that we intended to catch. */ |
e5ef252a PA |
2539 | |
2540 | if (debug_linux_nat) | |
2541 | fprintf_unfiltered (gdb_stdlog, | |
2bf6fb9d | 2542 | "SWC: Expected SIGSTOP caught for %s.\n", |
a068643d | 2543 | target_pid_to_str (lp->ptid).c_str ()); |
e5ef252a | 2544 | |
d6b0e80f | 2545 | lp->signalled = 0; |
7010835a AB |
2546 | |
2547 | /* If we are waiting for this stop so we can report the thread | |
2548 | stopped then we need to record this status. Otherwise, we can | |
2549 | now discard this stop event. */ | |
2550 | if (lp->last_resume_kind == resume_stop) | |
2551 | { | |
2552 | lp->status = status; | |
2553 | save_stop_reason (lp); | |
2554 | } | |
d6b0e80f AC |
2555 | } |
2556 | } | |
2557 | ||
2558 | return 0; | |
2559 | } | |
2560 | ||
9c02b525 PA |
2561 | /* Return non-zero if LP has a wait status pending. Discard the |
2562 | pending event and resume the LWP if the event that originally | |
2563 | caused the stop became uninteresting. */ | |
d6b0e80f AC |
2564 | |
2565 | static int | |
d3a70e03 | 2566 | status_callback (struct lwp_info *lp) |
d6b0e80f AC |
2567 | { |
2568 | /* Only report a pending wait status if we pretend that this has | |
2569 | indeed been resumed. */ | |
ca2163eb PA |
2570 | if (!lp->resumed) |
2571 | return 0; | |
2572 | ||
eb54c8bf PA |
2573 | if (!lwp_status_pending_p (lp)) |
2574 | return 0; | |
2575 | ||
15c66dd6 PA |
2576 | if (lp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT |
2577 | || lp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT) | |
9c02b525 PA |
2578 | { |
2579 | struct regcache *regcache = get_thread_regcache (lp->ptid); | |
9c02b525 PA |
2580 | CORE_ADDR pc; |
2581 | int discard = 0; | |
2582 | ||
9c02b525 PA |
2583 | pc = regcache_read_pc (regcache); |
2584 | ||
2585 | if (pc != lp->stop_pc) | |
2586 | { | |
2587 | if (debug_linux_nat) | |
2588 | fprintf_unfiltered (gdb_stdlog, | |
2589 | "SC: PC of %s changed. was=%s, now=%s\n", | |
a068643d | 2590 | target_pid_to_str (lp->ptid).c_str (), |
9c02b525 PA |
2591 | paddress (target_gdbarch (), lp->stop_pc), |
2592 | paddress (target_gdbarch (), pc)); | |
2593 | discard = 1; | |
2594 | } | |
faf09f01 PA |
2595 | |
2596 | #if !USE_SIGTRAP_SIGINFO | |
a01bda52 | 2597 | else if (!breakpoint_inserted_here_p (regcache->aspace (), pc)) |
9c02b525 PA |
2598 | { |
2599 | if (debug_linux_nat) | |
2600 | fprintf_unfiltered (gdb_stdlog, | |
2601 | "SC: previous breakpoint of %s, at %s gone\n", | |
a068643d | 2602 | target_pid_to_str (lp->ptid).c_str (), |
9c02b525 PA |
2603 | paddress (target_gdbarch (), lp->stop_pc)); |
2604 | ||
2605 | discard = 1; | |
2606 | } | |
faf09f01 | 2607 | #endif |
9c02b525 PA |
2608 | |
2609 | if (discard) | |
2610 | { | |
2611 | if (debug_linux_nat) | |
2612 | fprintf_unfiltered (gdb_stdlog, | |
2613 | "SC: pending event of %s cancelled.\n", | |
a068643d | 2614 | target_pid_to_str (lp->ptid).c_str ()); |
9c02b525 PA |
2615 | |
2616 | lp->status = 0; | |
2617 | linux_resume_one_lwp (lp, lp->step, GDB_SIGNAL_0); | |
2618 | return 0; | |
2619 | } | |
9c02b525 PA |
2620 | } |
2621 | ||
eb54c8bf | 2622 | return 1; |
d6b0e80f AC |
2623 | } |
2624 | ||
d6b0e80f AC |
2625 | /* Count the LWP's that have had events. */ |
2626 | ||
2627 | static int | |
d3a70e03 | 2628 | count_events_callback (struct lwp_info *lp, int *count) |
d6b0e80f | 2629 | { |
d6b0e80f AC |
2630 | gdb_assert (count != NULL); |
2631 | ||
9c02b525 PA |
2632 | /* Select only resumed LWPs that have an event pending. */ |
2633 | if (lp->resumed && lwp_status_pending_p (lp)) | |
d6b0e80f AC |
2634 | (*count)++; |
2635 | ||
2636 | return 0; | |
2637 | } | |
2638 | ||
2639 | /* Select the LWP (if any) that is currently being single-stepped. */ | |
2640 | ||
2641 | static int | |
d3a70e03 | 2642 | select_singlestep_lwp_callback (struct lwp_info *lp) |
d6b0e80f | 2643 | { |
25289eb2 PA |
2644 | if (lp->last_resume_kind == resume_step |
2645 | && lp->status != 0) | |
d6b0e80f AC |
2646 | return 1; |
2647 | else | |
2648 | return 0; | |
2649 | } | |
2650 | ||
8a99810d PA |
2651 | /* Returns true if LP has a status pending. */ |
2652 | ||
2653 | static int | |
2654 | lwp_status_pending_p (struct lwp_info *lp) | |
2655 | { | |
2656 | /* We check for lp->waitstatus in addition to lp->status, because we | |
2657 | can have pending process exits recorded in lp->status and | |
2658 | W_EXITCODE(0,0) happens to be 0. */ | |
2659 | return lp->status != 0 || lp->waitstatus.kind != TARGET_WAITKIND_IGNORE; | |
2660 | } | |
2661 | ||
b90fc188 | 2662 | /* Select the Nth LWP that has had an event. */ |
d6b0e80f AC |
2663 | |
2664 | static int | |
d3a70e03 | 2665 | select_event_lwp_callback (struct lwp_info *lp, int *selector) |
d6b0e80f | 2666 | { |
d6b0e80f AC |
2667 | gdb_assert (selector != NULL); |
2668 | ||
9c02b525 PA |
2669 | /* Select only resumed LWPs that have an event pending. */ |
2670 | if (lp->resumed && lwp_status_pending_p (lp)) | |
d6b0e80f AC |
2671 | if ((*selector)-- == 0) |
2672 | return 1; | |
2673 | ||
2674 | return 0; | |
2675 | } | |
2676 | ||
e7ad2f14 PA |
2677 | /* Called when the LWP stopped for a signal/trap. If it stopped for a |
2678 | trap check what caused it (breakpoint, watchpoint, trace, etc.), | |
2679 | and save the result in the LWP's stop_reason field. If it stopped | |
2680 | for a breakpoint, decrement the PC if necessary on the lwp's | |
2681 | architecture. */ | |
9c02b525 | 2682 | |
e7ad2f14 PA |
2683 | static void |
2684 | save_stop_reason (struct lwp_info *lp) | |
710151dd | 2685 | { |
e7ad2f14 PA |
2686 | struct regcache *regcache; |
2687 | struct gdbarch *gdbarch; | |
515630c5 | 2688 | CORE_ADDR pc; |
9c02b525 | 2689 | CORE_ADDR sw_bp_pc; |
faf09f01 PA |
2690 | #if USE_SIGTRAP_SIGINFO |
2691 | siginfo_t siginfo; | |
2692 | #endif | |
9c02b525 | 2693 | |
e7ad2f14 PA |
2694 | gdb_assert (lp->stop_reason == TARGET_STOPPED_BY_NO_REASON); |
2695 | gdb_assert (lp->status != 0); | |
2696 | ||
135340af | 2697 | if (!linux_target->low_status_is_event (lp->status)) |
e7ad2f14 PA |
2698 | return; |
2699 | ||
2700 | regcache = get_thread_regcache (lp->ptid); | |
ac7936df | 2701 | gdbarch = regcache->arch (); |
e7ad2f14 | 2702 | |
9c02b525 | 2703 | pc = regcache_read_pc (regcache); |
527a273a | 2704 | sw_bp_pc = pc - gdbarch_decr_pc_after_break (gdbarch); |
515630c5 | 2705 | |
faf09f01 PA |
2706 | #if USE_SIGTRAP_SIGINFO |
2707 | if (linux_nat_get_siginfo (lp->ptid, &siginfo)) | |
2708 | { | |
2709 | if (siginfo.si_signo == SIGTRAP) | |
2710 | { | |
e7ad2f14 PA |
2711 | if (GDB_ARCH_IS_TRAP_BRKPT (siginfo.si_code) |
2712 | && GDB_ARCH_IS_TRAP_HWBKPT (siginfo.si_code)) | |
faf09f01 | 2713 | { |
e7ad2f14 PA |
2714 | /* The si_code is ambiguous on this arch -- check debug |
2715 | registers. */ | |
2716 | if (!check_stopped_by_watchpoint (lp)) | |
2717 | lp->stop_reason = TARGET_STOPPED_BY_SW_BREAKPOINT; | |
2718 | } | |
2719 | else if (GDB_ARCH_IS_TRAP_BRKPT (siginfo.si_code)) | |
2720 | { | |
2721 | /* If we determine the LWP stopped for a SW breakpoint, | |
2722 | trust it. Particularly don't check watchpoint | |
2723 | registers, because at least on s390, we'd find | |
2724 | stopped-by-watchpoint as long as there's a watchpoint | |
2725 | set. */ | |
faf09f01 | 2726 | lp->stop_reason = TARGET_STOPPED_BY_SW_BREAKPOINT; |
faf09f01 | 2727 | } |
e7ad2f14 | 2728 | else if (GDB_ARCH_IS_TRAP_HWBKPT (siginfo.si_code)) |
faf09f01 | 2729 | { |
e7ad2f14 PA |
2730 | /* This can indicate either a hardware breakpoint or |
2731 | hardware watchpoint. Check debug registers. */ | |
2732 | if (!check_stopped_by_watchpoint (lp)) | |
2733 | lp->stop_reason = TARGET_STOPPED_BY_HW_BREAKPOINT; | |
faf09f01 | 2734 | } |
2bf6fb9d PA |
2735 | else if (siginfo.si_code == TRAP_TRACE) |
2736 | { | |
2737 | if (debug_linux_nat) | |
2738 | fprintf_unfiltered (gdb_stdlog, | |
2739 | "CSBB: %s stopped by trace\n", | |
a068643d | 2740 | target_pid_to_str (lp->ptid).c_str ()); |
e7ad2f14 PA |
2741 | |
2742 | /* We may have single stepped an instruction that | |
2743 | triggered a watchpoint. In that case, on some | |
2744 | architectures (such as x86), instead of TRAP_HWBKPT, | |
2745 | si_code indicates TRAP_TRACE, and we need to check | |
2746 | the debug registers separately. */ | |
2747 | check_stopped_by_watchpoint (lp); | |
2bf6fb9d | 2748 | } |
faf09f01 PA |
2749 | } |
2750 | } | |
2751 | #else | |
9c02b525 | 2752 | if ((!lp->step || lp->stop_pc == sw_bp_pc) |
a01bda52 | 2753 | && software_breakpoint_inserted_here_p (regcache->aspace (), |
9c02b525 | 2754 | sw_bp_pc)) |
710151dd | 2755 | { |
9c02b525 PA |
2756 | /* The LWP was either continued, or stepped a software |
2757 | breakpoint instruction. */ | |
e7ad2f14 PA |
2758 | lp->stop_reason = TARGET_STOPPED_BY_SW_BREAKPOINT; |
2759 | } | |
2760 | ||
a01bda52 | 2761 | if (hardware_breakpoint_inserted_here_p (regcache->aspace (), pc)) |
e7ad2f14 PA |
2762 | lp->stop_reason = TARGET_STOPPED_BY_HW_BREAKPOINT; |
2763 | ||
2764 | if (lp->stop_reason == TARGET_STOPPED_BY_NO_REASON) | |
2765 | check_stopped_by_watchpoint (lp); | |
2766 | #endif | |
2767 | ||
2768 | if (lp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT) | |
2769 | { | |
710151dd PA |
2770 | if (debug_linux_nat) |
2771 | fprintf_unfiltered (gdb_stdlog, | |
2bf6fb9d | 2772 | "CSBB: %s stopped by software breakpoint\n", |
a068643d | 2773 | target_pid_to_str (lp->ptid).c_str ()); |
710151dd PA |
2774 | |
2775 | /* Back up the PC if necessary. */ | |
9c02b525 PA |
2776 | if (pc != sw_bp_pc) |
2777 | regcache_write_pc (regcache, sw_bp_pc); | |
515630c5 | 2778 | |
e7ad2f14 PA |
2779 | /* Update this so we record the correct stop PC below. */ |
2780 | pc = sw_bp_pc; | |
710151dd | 2781 | } |
e7ad2f14 | 2782 | else if (lp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT) |
9c02b525 PA |
2783 | { |
2784 | if (debug_linux_nat) | |
2785 | fprintf_unfiltered (gdb_stdlog, | |
e7ad2f14 | 2786 | "CSBB: %s stopped by hardware breakpoint\n", |
a068643d | 2787 | target_pid_to_str (lp->ptid).c_str ()); |
e7ad2f14 PA |
2788 | } |
2789 | else if (lp->stop_reason == TARGET_STOPPED_BY_WATCHPOINT) | |
2790 | { | |
2791 | if (debug_linux_nat) | |
2792 | fprintf_unfiltered (gdb_stdlog, | |
2793 | "CSBB: %s stopped by hardware watchpoint\n", | |
a068643d | 2794 | target_pid_to_str (lp->ptid).c_str ()); |
9c02b525 | 2795 | } |
d6b0e80f | 2796 | |
e7ad2f14 | 2797 | lp->stop_pc = pc; |
d6b0e80f AC |
2798 | } |
2799 | ||
faf09f01 PA |
2800 | |
2801 | /* Returns true if the LWP had stopped for a software breakpoint. */ | |
2802 | ||
57810aa7 | 2803 | bool |
f6ac5f3d | 2804 | linux_nat_target::stopped_by_sw_breakpoint () |
faf09f01 PA |
2805 | { |
2806 | struct lwp_info *lp = find_lwp_pid (inferior_ptid); | |
2807 | ||
2808 | gdb_assert (lp != NULL); | |
2809 | ||
2810 | return lp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT; | |
2811 | } | |
2812 | ||
2813 | /* Implement the supports_stopped_by_sw_breakpoint method. */ | |
2814 | ||
57810aa7 | 2815 | bool |
f6ac5f3d | 2816 | linux_nat_target::supports_stopped_by_sw_breakpoint () |
faf09f01 PA |
2817 | { |
2818 | return USE_SIGTRAP_SIGINFO; | |
2819 | } | |
2820 | ||
2821 | /* Returns true if the LWP had stopped for a hardware | |
2822 | breakpoint/watchpoint. */ | |
2823 | ||
57810aa7 | 2824 | bool |
f6ac5f3d | 2825 | linux_nat_target::stopped_by_hw_breakpoint () |
faf09f01 PA |
2826 | { |
2827 | struct lwp_info *lp = find_lwp_pid (inferior_ptid); | |
2828 | ||
2829 | gdb_assert (lp != NULL); | |
2830 | ||
2831 | return lp->stop_reason == TARGET_STOPPED_BY_HW_BREAKPOINT; | |
2832 | } | |
2833 | ||
2834 | /* Implement the supports_stopped_by_hw_breakpoint method. */ | |
2835 | ||
57810aa7 | 2836 | bool |
f6ac5f3d | 2837 | linux_nat_target::supports_stopped_by_hw_breakpoint () |
faf09f01 PA |
2838 | { |
2839 | return USE_SIGTRAP_SIGINFO; | |
2840 | } | |
2841 | ||
d6b0e80f AC |
2842 | /* Select one LWP out of those that have events pending. */ |
2843 | ||
2844 | static void | |
d90e17a7 | 2845 | select_event_lwp (ptid_t filter, struct lwp_info **orig_lp, int *status) |
d6b0e80f AC |
2846 | { |
2847 | int num_events = 0; | |
2848 | int random_selector; | |
9c02b525 | 2849 | struct lwp_info *event_lp = NULL; |
d6b0e80f | 2850 | |
ac264b3b | 2851 | /* Record the wait status for the original LWP. */ |
d6b0e80f AC |
2852 | (*orig_lp)->status = *status; |
2853 | ||
9c02b525 PA |
2854 | /* In all-stop, give preference to the LWP that is being |
2855 | single-stepped. There will be at most one, and it will be the | |
2856 | LWP that the core is most interested in. If we didn't do this, | |
2857 | then we'd have to handle pending step SIGTRAPs somehow in case | |
2858 | the core later continues the previously-stepped thread, as | |
2859 | otherwise we'd report the pending SIGTRAP then, and the core, not | |
2860 | having stepped the thread, wouldn't understand what the trap was | |
2861 | for, and therefore would report it to the user as a random | |
2862 | signal. */ | |
fbea99ea | 2863 | if (!target_is_non_stop_p ()) |
d6b0e80f | 2864 | { |
d3a70e03 | 2865 | event_lp = iterate_over_lwps (filter, select_singlestep_lwp_callback); |
9c02b525 PA |
2866 | if (event_lp != NULL) |
2867 | { | |
2868 | if (debug_linux_nat) | |
2869 | fprintf_unfiltered (gdb_stdlog, | |
2870 | "SEL: Select single-step %s\n", | |
a068643d | 2871 | target_pid_to_str (event_lp->ptid).c_str ()); |
9c02b525 | 2872 | } |
d6b0e80f | 2873 | } |
9c02b525 PA |
2874 | |
2875 | if (event_lp == NULL) | |
d6b0e80f | 2876 | { |
9c02b525 | 2877 | /* Pick one at random, out of those which have had events. */ |
d6b0e80f | 2878 | |
9c02b525 | 2879 | /* First see how many events we have. */ |
d3a70e03 TT |
2880 | iterate_over_lwps (filter, |
2881 | [&] (struct lwp_info *info) | |
2882 | { | |
2883 | return count_events_callback (info, &num_events); | |
2884 | }); | |
8bf3b159 | 2885 | gdb_assert (num_events > 0); |
d6b0e80f | 2886 | |
9c02b525 PA |
2887 | /* Now randomly pick a LWP out of those that have had |
2888 | events. */ | |
d6b0e80f AC |
2889 | random_selector = (int) |
2890 | ((num_events * (double) rand ()) / (RAND_MAX + 1.0)); | |
2891 | ||
2892 | if (debug_linux_nat && num_events > 1) | |
2893 | fprintf_unfiltered (gdb_stdlog, | |
9c02b525 | 2894 | "SEL: Found %d events, selecting #%d\n", |
d6b0e80f AC |
2895 | num_events, random_selector); |
2896 | ||
d3a70e03 TT |
2897 | event_lp |
2898 | = (iterate_over_lwps | |
2899 | (filter, | |
2900 | [&] (struct lwp_info *info) | |
2901 | { | |
2902 | return select_event_lwp_callback (info, | |
2903 | &random_selector); | |
2904 | })); | |
d6b0e80f AC |
2905 | } |
2906 | ||
2907 | if (event_lp != NULL) | |
2908 | { | |
2909 | /* Switch the event LWP. */ | |
2910 | *orig_lp = event_lp; | |
2911 | *status = event_lp->status; | |
2912 | } | |
2913 | ||
2914 | /* Flush the wait status for the event LWP. */ | |
2915 | (*orig_lp)->status = 0; | |
2916 | } | |
2917 | ||
2918 | /* Return non-zero if LP has been resumed. */ | |
2919 | ||
2920 | static int | |
d3a70e03 | 2921 | resumed_callback (struct lwp_info *lp) |
d6b0e80f AC |
2922 | { |
2923 | return lp->resumed; | |
2924 | } | |
2925 | ||
02f3fc28 | 2926 | /* Check if we should go on and pass this event to common code. |
9c02b525 | 2927 | Return the affected lwp if we are, or NULL otherwise. */ |
12d9289a | 2928 | |
02f3fc28 | 2929 | static struct lwp_info * |
9c02b525 | 2930 | linux_nat_filter_event (int lwpid, int status) |
02f3fc28 PA |
2931 | { |
2932 | struct lwp_info *lp; | |
89a5711c | 2933 | int event = linux_ptrace_get_extended_event (status); |
02f3fc28 | 2934 | |
f2907e49 | 2935 | lp = find_lwp_pid (ptid_t (lwpid)); |
02f3fc28 PA |
2936 | |
2937 | /* Check for stop events reported by a process we didn't already | |
2938 | know about - anything not already in our LWP list. | |
2939 | ||
2940 | If we're expecting to receive stopped processes after | |
2941 | fork, vfork, and clone events, then we'll just add the | |
2942 | new one to our list and go back to waiting for the event | |
2943 | to be reported - the stopped process might be returned | |
0e5bf2a8 PA |
2944 | from waitpid before or after the event is. |
2945 | ||
2946 | But note the case of a non-leader thread exec'ing after the | |
2947 | leader having exited, and gone from our lists. The non-leader | |
2948 | thread changes its tid to the tgid. */ | |
2949 | ||
2950 | if (WIFSTOPPED (status) && lp == NULL | |
89a5711c | 2951 | && (WSTOPSIG (status) == SIGTRAP && event == PTRACE_EVENT_EXEC)) |
0e5bf2a8 PA |
2952 | { |
2953 | /* A multi-thread exec after we had seen the leader exiting. */ | |
2954 | if (debug_linux_nat) | |
2955 | fprintf_unfiltered (gdb_stdlog, | |
2956 | "LLW: Re-adding thread group leader LWP %d.\n", | |
2957 | lwpid); | |
2958 | ||
fd79271b | 2959 | lp = add_lwp (ptid_t (lwpid, lwpid, 0)); |
0e5bf2a8 PA |
2960 | lp->stopped = 1; |
2961 | lp->resumed = 1; | |
2962 | add_thread (lp->ptid); | |
2963 | } | |
2964 | ||
02f3fc28 PA |
2965 | if (WIFSTOPPED (status) && !lp) |
2966 | { | |
3b27ef47 PA |
2967 | if (debug_linux_nat) |
2968 | fprintf_unfiltered (gdb_stdlog, | |
2969 | "LHEW: saving LWP %ld status %s in stopped_pids list\n", | |
2970 | (long) lwpid, status_to_str (status)); | |
84636d28 | 2971 | add_to_pid_list (&stopped_pids, lwpid, status); |
02f3fc28 PA |
2972 | return NULL; |
2973 | } | |
2974 | ||
2975 | /* Make sure we don't report an event for the exit of an LWP not in | |
1777feb0 | 2976 | our list, i.e. not part of the current process. This can happen |
fd62cb89 | 2977 | if we detach from a program we originally forked and then it |
02f3fc28 PA |
2978 | exits. */ |
2979 | if (!WIFSTOPPED (status) && !lp) | |
2980 | return NULL; | |
2981 | ||
8817a6f2 PA |
2982 | /* This LWP is stopped now. (And if dead, this prevents it from |
2983 | ever being continued.) */ | |
2984 | lp->stopped = 1; | |
2985 | ||
8784d563 PA |
2986 | if (WIFSTOPPED (status) && lp->must_set_ptrace_flags) |
2987 | { | |
e99b03dc | 2988 | struct inferior *inf = find_inferior_pid (lp->ptid.pid ()); |
de0d863e | 2989 | int options = linux_nat_ptrace_options (inf->attach_flag); |
8784d563 | 2990 | |
e38504b3 | 2991 | linux_enable_event_reporting (lp->ptid.lwp (), options); |
8784d563 PA |
2992 | lp->must_set_ptrace_flags = 0; |
2993 | } | |
2994 | ||
ca2163eb PA |
2995 | /* Handle GNU/Linux's syscall SIGTRAPs. */ |
2996 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SYSCALL_SIGTRAP) | |
2997 | { | |
2998 | /* No longer need the sysgood bit. The ptrace event ends up | |
2999 | recorded in lp->waitstatus if we care for it. We can carry | |
3000 | on handling the event like a regular SIGTRAP from here | |
3001 | on. */ | |
3002 | status = W_STOPCODE (SIGTRAP); | |
3003 | if (linux_handle_syscall_trap (lp, 0)) | |
3004 | return NULL; | |
3005 | } | |
bfd09d20 JS |
3006 | else |
3007 | { | |
3008 | /* Almost all other ptrace-stops are known to be outside of system | |
3009 | calls, with further exceptions in linux_handle_extended_wait. */ | |
3010 | lp->syscall_state = TARGET_WAITKIND_IGNORE; | |
3011 | } | |
02f3fc28 | 3012 | |
ca2163eb | 3013 | /* Handle GNU/Linux's extended waitstatus for trace events. */ |
89a5711c DB |
3014 | if (WIFSTOPPED (status) && WSTOPSIG (status) == SIGTRAP |
3015 | && linux_is_extended_waitstatus (status)) | |
02f3fc28 PA |
3016 | { |
3017 | if (debug_linux_nat) | |
3018 | fprintf_unfiltered (gdb_stdlog, | |
3019 | "LLW: Handling extended status 0x%06x\n", | |
3020 | status); | |
4dd63d48 | 3021 | if (linux_handle_extended_wait (lp, status)) |
02f3fc28 PA |
3022 | return NULL; |
3023 | } | |
3024 | ||
3025 | /* Check if the thread has exited. */ | |
9c02b525 PA |
3026 | if (WIFEXITED (status) || WIFSIGNALED (status)) |
3027 | { | |
aa01bd36 | 3028 | if (!report_thread_events |
e99b03dc | 3029 | && num_lwps (lp->ptid.pid ()) > 1) |
02f3fc28 | 3030 | { |
9c02b525 PA |
3031 | if (debug_linux_nat) |
3032 | fprintf_unfiltered (gdb_stdlog, | |
3033 | "LLW: %s exited.\n", | |
a068643d | 3034 | target_pid_to_str (lp->ptid).c_str ()); |
9c02b525 | 3035 | |
4a6ed09b PA |
3036 | /* If there is at least one more LWP, then the exit signal |
3037 | was not the end of the debugged application and should be | |
3038 | ignored. */ | |
3039 | exit_lwp (lp); | |
3040 | return NULL; | |
02f3fc28 PA |
3041 | } |
3042 | ||
77598427 PA |
3043 | /* Note that even if the leader was ptrace-stopped, it can still |
3044 | exit, if e.g., some other thread brings down the whole | |
3045 | process (calls `exit'). So don't assert that the lwp is | |
3046 | resumed. */ | |
02f3fc28 PA |
3047 | if (debug_linux_nat) |
3048 | fprintf_unfiltered (gdb_stdlog, | |
aa01bd36 | 3049 | "LWP %ld exited (resumed=%d)\n", |
e38504b3 | 3050 | lp->ptid.lwp (), lp->resumed); |
02f3fc28 | 3051 | |
9c02b525 PA |
3052 | /* Dead LWP's aren't expected to reported a pending sigstop. */ |
3053 | lp->signalled = 0; | |
3054 | ||
3055 | /* Store the pending event in the waitstatus, because | |
3056 | W_EXITCODE(0,0) == 0. */ | |
3057 | store_waitstatus (&lp->waitstatus, status); | |
3058 | return lp; | |
02f3fc28 PA |
3059 | } |
3060 | ||
02f3fc28 PA |
3061 | /* Make sure we don't report a SIGSTOP that we sent ourselves in |
3062 | an attempt to stop an LWP. */ | |
3063 | if (lp->signalled | |
3064 | && WIFSTOPPED (status) && WSTOPSIG (status) == SIGSTOP) | |
3065 | { | |
02f3fc28 PA |
3066 | lp->signalled = 0; |
3067 | ||
2bf6fb9d | 3068 | if (lp->last_resume_kind == resume_stop) |
25289eb2 | 3069 | { |
2bf6fb9d PA |
3070 | if (debug_linux_nat) |
3071 | fprintf_unfiltered (gdb_stdlog, | |
3072 | "LLW: resume_stop SIGSTOP caught for %s.\n", | |
a068643d | 3073 | target_pid_to_str (lp->ptid).c_str ()); |
2bf6fb9d PA |
3074 | } |
3075 | else | |
3076 | { | |
3077 | /* This is a delayed SIGSTOP. Filter out the event. */ | |
02f3fc28 | 3078 | |
25289eb2 PA |
3079 | if (debug_linux_nat) |
3080 | fprintf_unfiltered (gdb_stdlog, | |
2bf6fb9d | 3081 | "LLW: %s %s, 0, 0 (discard delayed SIGSTOP)\n", |
25289eb2 PA |
3082 | lp->step ? |
3083 | "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
a068643d | 3084 | target_pid_to_str (lp->ptid).c_str ()); |
02f3fc28 | 3085 | |
2bf6fb9d | 3086 | linux_resume_one_lwp (lp, lp->step, GDB_SIGNAL_0); |
25289eb2 | 3087 | gdb_assert (lp->resumed); |
25289eb2 PA |
3088 | return NULL; |
3089 | } | |
02f3fc28 PA |
3090 | } |
3091 | ||
57380f4e DJ |
3092 | /* Make sure we don't report a SIGINT that we have already displayed |
3093 | for another thread. */ | |
3094 | if (lp->ignore_sigint | |
3095 | && WIFSTOPPED (status) && WSTOPSIG (status) == SIGINT) | |
3096 | { | |
3097 | if (debug_linux_nat) | |
3098 | fprintf_unfiltered (gdb_stdlog, | |
3099 | "LLW: Delayed SIGINT caught for %s.\n", | |
a068643d | 3100 | target_pid_to_str (lp->ptid).c_str ()); |
57380f4e DJ |
3101 | |
3102 | /* This is a delayed SIGINT. */ | |
3103 | lp->ignore_sigint = 0; | |
3104 | ||
8a99810d | 3105 | linux_resume_one_lwp (lp, lp->step, GDB_SIGNAL_0); |
57380f4e DJ |
3106 | if (debug_linux_nat) |
3107 | fprintf_unfiltered (gdb_stdlog, | |
3108 | "LLW: %s %s, 0, 0 (discard SIGINT)\n", | |
3109 | lp->step ? | |
3110 | "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
a068643d | 3111 | target_pid_to_str (lp->ptid).c_str ()); |
57380f4e DJ |
3112 | gdb_assert (lp->resumed); |
3113 | ||
3114 | /* Discard the event. */ | |
3115 | return NULL; | |
3116 | } | |
3117 | ||
9c02b525 PA |
3118 | /* Don't report signals that GDB isn't interested in, such as |
3119 | signals that are neither printed nor stopped upon. Stopping all | |
3120 | threads can be a bit time-consuming so if we want decent | |
3121 | performance with heavily multi-threaded programs, especially when | |
3122 | they're using a high frequency timer, we'd better avoid it if we | |
3123 | can. */ | |
3124 | if (WIFSTOPPED (status)) | |
3125 | { | |
3126 | enum gdb_signal signo = gdb_signal_from_host (WSTOPSIG (status)); | |
3127 | ||
fbea99ea | 3128 | if (!target_is_non_stop_p ()) |
9c02b525 PA |
3129 | { |
3130 | /* Only do the below in all-stop, as we currently use SIGSTOP | |
3131 | to implement target_stop (see linux_nat_stop) in | |
3132 | non-stop. */ | |
3133 | if (signo == GDB_SIGNAL_INT && signal_pass_state (signo) == 0) | |
3134 | { | |
3135 | /* If ^C/BREAK is typed at the tty/console, SIGINT gets | |
3136 | forwarded to the entire process group, that is, all LWPs | |
3137 | will receive it - unless they're using CLONE_THREAD to | |
3138 | share signals. Since we only want to report it once, we | |
3139 | mark it as ignored for all LWPs except this one. */ | |
d3a70e03 | 3140 | iterate_over_lwps (ptid_t (lp->ptid.pid ()), set_ignore_sigint); |
9c02b525 PA |
3141 | lp->ignore_sigint = 0; |
3142 | } | |
3143 | else | |
3144 | maybe_clear_ignore_sigint (lp); | |
3145 | } | |
3146 | ||
3147 | /* When using hardware single-step, we need to report every signal. | |
c9587f88 | 3148 | Otherwise, signals in pass_mask may be short-circuited |
d8c06f22 AB |
3149 | except signals that might be caused by a breakpoint, or SIGSTOP |
3150 | if we sent the SIGSTOP and are waiting for it to arrive. */ | |
9c02b525 | 3151 | if (!lp->step |
c9587f88 | 3152 | && WSTOPSIG (status) && sigismember (&pass_mask, WSTOPSIG (status)) |
d8c06f22 AB |
3153 | && (WSTOPSIG (status) != SIGSTOP |
3154 | || !find_thread_ptid (lp->ptid)->stop_requested) | |
c9587f88 | 3155 | && !linux_wstatus_maybe_breakpoint (status)) |
9c02b525 PA |
3156 | { |
3157 | linux_resume_one_lwp (lp, lp->step, signo); | |
3158 | if (debug_linux_nat) | |
3159 | fprintf_unfiltered (gdb_stdlog, | |
3160 | "LLW: %s %s, %s (preempt 'handle')\n", | |
3161 | lp->step ? | |
3162 | "PTRACE_SINGLESTEP" : "PTRACE_CONT", | |
a068643d | 3163 | target_pid_to_str (lp->ptid).c_str (), |
9c02b525 PA |
3164 | (signo != GDB_SIGNAL_0 |
3165 | ? strsignal (gdb_signal_to_host (signo)) | |
3166 | : "0")); | |
3167 | return NULL; | |
3168 | } | |
3169 | } | |
3170 | ||
02f3fc28 PA |
3171 | /* An interesting event. */ |
3172 | gdb_assert (lp); | |
ca2163eb | 3173 | lp->status = status; |
e7ad2f14 | 3174 | save_stop_reason (lp); |
02f3fc28 PA |
3175 | return lp; |
3176 | } | |
3177 | ||
0e5bf2a8 PA |
3178 | /* Detect zombie thread group leaders, and "exit" them. We can't reap |
3179 | their exits until all other threads in the group have exited. */ | |
3180 | ||
3181 | static void | |
3182 | check_zombie_leaders (void) | |
3183 | { | |
08036331 | 3184 | for (inferior *inf : all_inferiors ()) |
0e5bf2a8 PA |
3185 | { |
3186 | struct lwp_info *leader_lp; | |
3187 | ||
3188 | if (inf->pid == 0) | |
3189 | continue; | |
3190 | ||
f2907e49 | 3191 | leader_lp = find_lwp_pid (ptid_t (inf->pid)); |
0e5bf2a8 PA |
3192 | if (leader_lp != NULL |
3193 | /* Check if there are other threads in the group, as we may | |
3194 | have raced with the inferior simply exiting. */ | |
3195 | && num_lwps (inf->pid) > 1 | |
5f572dec | 3196 | && linux_proc_pid_is_zombie (inf->pid)) |
0e5bf2a8 PA |
3197 | { |
3198 | if (debug_linux_nat) | |
3199 | fprintf_unfiltered (gdb_stdlog, | |
3200 | "CZL: Thread group leader %d zombie " | |
3201 | "(it exited, or another thread execd).\n", | |
3202 | inf->pid); | |
3203 | ||
3204 | /* A leader zombie can mean one of two things: | |
3205 | ||
3206 | - It exited, and there's an exit status pending | |
3207 | available, or only the leader exited (not the whole | |
3208 | program). In the latter case, we can't waitpid the | |
3209 | leader's exit status until all other threads are gone. | |
3210 | ||
3211 | - There are 3 or more threads in the group, and a thread | |
4a6ed09b PA |
3212 | other than the leader exec'd. See comments on exec |
3213 | events at the top of the file. We could try | |
0e5bf2a8 PA |
3214 | distinguishing the exit and exec cases, by waiting once |
3215 | more, and seeing if something comes out, but it doesn't | |
3216 | sound useful. The previous leader _does_ go away, and | |
3217 | we'll re-add the new one once we see the exec event | |
3218 | (which is just the same as what would happen if the | |
3219 | previous leader did exit voluntarily before some other | |
3220 | thread execs). */ | |
3221 | ||
3222 | if (debug_linux_nat) | |
3223 | fprintf_unfiltered (gdb_stdlog, | |
3224 | "CZL: Thread group leader %d vanished.\n", | |
3225 | inf->pid); | |
3226 | exit_lwp (leader_lp); | |
3227 | } | |
3228 | } | |
3229 | } | |
3230 | ||
aa01bd36 PA |
3231 | /* Convenience function that is called when the kernel reports an exit |
3232 | event. This decides whether to report the event to GDB as a | |
3233 | process exit event, a thread exit event, or to suppress the | |
3234 | event. */ | |
3235 | ||
3236 | static ptid_t | |
3237 | filter_exit_event (struct lwp_info *event_child, | |
3238 | struct target_waitstatus *ourstatus) | |
3239 | { | |
3240 | ptid_t ptid = event_child->ptid; | |
3241 | ||
e99b03dc | 3242 | if (num_lwps (ptid.pid ()) > 1) |
aa01bd36 PA |
3243 | { |
3244 | if (report_thread_events) | |
3245 | ourstatus->kind = TARGET_WAITKIND_THREAD_EXITED; | |
3246 | else | |
3247 | ourstatus->kind = TARGET_WAITKIND_IGNORE; | |
3248 | ||
3249 | exit_lwp (event_child); | |
3250 | } | |
3251 | ||
3252 | return ptid; | |
3253 | } | |
3254 | ||
d6b0e80f | 3255 | static ptid_t |
f6ac5f3d | 3256 | linux_nat_wait_1 (ptid_t ptid, struct target_waitstatus *ourstatus, |
47608cb1 | 3257 | int target_options) |
d6b0e80f | 3258 | { |
fc9b8e47 | 3259 | sigset_t prev_mask; |
4b60df3d | 3260 | enum resume_kind last_resume_kind; |
12d9289a | 3261 | struct lwp_info *lp; |
12d9289a | 3262 | int status; |
d6b0e80f | 3263 | |
01124a23 | 3264 | if (debug_linux_nat) |
b84876c2 PA |
3265 | fprintf_unfiltered (gdb_stdlog, "LLW: enter\n"); |
3266 | ||
f973ed9c DJ |
3267 | /* The first time we get here after starting a new inferior, we may |
3268 | not have added it to the LWP list yet - this is the earliest | |
3269 | moment at which we know its PID. */ | |
0e998d96 | 3270 | if (inferior_ptid.is_pid ()) |
f973ed9c | 3271 | { |
27c9d204 PA |
3272 | /* Upgrade the main thread's ptid. */ |
3273 | thread_change_ptid (inferior_ptid, | |
e99b03dc TT |
3274 | ptid_t (inferior_ptid.pid (), |
3275 | inferior_ptid.pid (), 0)); | |
27c9d204 | 3276 | |
26cb8b7c | 3277 | lp = add_initial_lwp (inferior_ptid); |
f973ed9c DJ |
3278 | lp->resumed = 1; |
3279 | } | |
3280 | ||
12696c10 | 3281 | /* Make sure SIGCHLD is blocked until the sigsuspend below. */ |
7feb7d06 | 3282 | block_child_signals (&prev_mask); |
d6b0e80f | 3283 | |
d6b0e80f | 3284 | /* First check if there is a LWP with a wait status pending. */ |
d3a70e03 | 3285 | lp = iterate_over_lwps (ptid, status_callback); |
8a99810d | 3286 | if (lp != NULL) |
d6b0e80f AC |
3287 | { |
3288 | if (debug_linux_nat) | |
d6b0e80f AC |
3289 | fprintf_unfiltered (gdb_stdlog, |
3290 | "LLW: Using pending wait status %s for %s.\n", | |
ca2163eb | 3291 | status_to_str (lp->status), |
a068643d | 3292 | target_pid_to_str (lp->ptid).c_str ()); |
d6b0e80f AC |
3293 | } |
3294 | ||
9c02b525 PA |
3295 | /* But if we don't find a pending event, we'll have to wait. Always |
3296 | pull all events out of the kernel. We'll randomly select an | |
3297 | event LWP out of all that have events, to prevent starvation. */ | |
7feb7d06 | 3298 | |
d90e17a7 | 3299 | while (lp == NULL) |
d6b0e80f AC |
3300 | { |
3301 | pid_t lwpid; | |
3302 | ||
0e5bf2a8 PA |
3303 | /* Always use -1 and WNOHANG, due to couple of a kernel/ptrace |
3304 | quirks: | |
3305 | ||
3306 | - If the thread group leader exits while other threads in the | |
3307 | thread group still exist, waitpid(TGID, ...) hangs. That | |
3308 | waitpid won't return an exit status until the other threads | |
85102364 | 3309 | in the group are reaped. |
0e5bf2a8 PA |
3310 | |
3311 | - When a non-leader thread execs, that thread just vanishes | |
3312 | without reporting an exit (so we'd hang if we waited for it | |
3313 | explicitly in that case). The exec event is reported to | |
3314 | the TGID pid. */ | |
3315 | ||
3316 | errno = 0; | |
4a6ed09b | 3317 | lwpid = my_waitpid (-1, &status, __WALL | WNOHANG); |
0e5bf2a8 PA |
3318 | |
3319 | if (debug_linux_nat) | |
3320 | fprintf_unfiltered (gdb_stdlog, | |
3321 | "LNW: waitpid(-1, ...) returned %d, %s\n", | |
3322 | lwpid, errno ? safe_strerror (errno) : "ERRNO-OK"); | |
b84876c2 | 3323 | |
d6b0e80f AC |
3324 | if (lwpid > 0) |
3325 | { | |
d6b0e80f AC |
3326 | if (debug_linux_nat) |
3327 | { | |
3328 | fprintf_unfiltered (gdb_stdlog, | |
3329 | "LLW: waitpid %ld received %s\n", | |
3330 | (long) lwpid, status_to_str (status)); | |
3331 | } | |
3332 | ||
9c02b525 | 3333 | linux_nat_filter_event (lwpid, status); |
0e5bf2a8 PA |
3334 | /* Retry until nothing comes out of waitpid. A single |
3335 | SIGCHLD can indicate more than one child stopped. */ | |
3336 | continue; | |
d6b0e80f AC |
3337 | } |
3338 | ||
20ba1ce6 PA |
3339 | /* Now that we've pulled all events out of the kernel, resume |
3340 | LWPs that don't have an interesting event to report. */ | |
3341 | iterate_over_lwps (minus_one_ptid, | |
d3a70e03 TT |
3342 | [] (struct lwp_info *info) |
3343 | { | |
3344 | return resume_stopped_resumed_lwps (info, minus_one_ptid); | |
3345 | }); | |
20ba1ce6 PA |
3346 | |
3347 | /* ... and find an LWP with a status to report to the core, if | |
3348 | any. */ | |
d3a70e03 | 3349 | lp = iterate_over_lwps (ptid, status_callback); |
9c02b525 PA |
3350 | if (lp != NULL) |
3351 | break; | |
3352 | ||
0e5bf2a8 PA |
3353 | /* Check for zombie thread group leaders. Those can't be reaped |
3354 | until all other threads in the thread group are. */ | |
3355 | check_zombie_leaders (); | |
d6b0e80f | 3356 | |
0e5bf2a8 PA |
3357 | /* If there are no resumed children left, bail. We'd be stuck |
3358 | forever in the sigsuspend call below otherwise. */ | |
d3a70e03 | 3359 | if (iterate_over_lwps (ptid, resumed_callback) == NULL) |
0e5bf2a8 PA |
3360 | { |
3361 | if (debug_linux_nat) | |
3362 | fprintf_unfiltered (gdb_stdlog, "LLW: exit (no resumed LWP)\n"); | |
b84876c2 | 3363 | |
0e5bf2a8 | 3364 | ourstatus->kind = TARGET_WAITKIND_NO_RESUMED; |
b84876c2 | 3365 | |
0e5bf2a8 PA |
3366 | restore_child_signals_mask (&prev_mask); |
3367 | return minus_one_ptid; | |
d6b0e80f | 3368 | } |
28736962 | 3369 | |
0e5bf2a8 PA |
3370 | /* No interesting event to report to the core. */ |
3371 | ||
3372 | if (target_options & TARGET_WNOHANG) | |
3373 | { | |
01124a23 | 3374 | if (debug_linux_nat) |
28736962 PA |
3375 | fprintf_unfiltered (gdb_stdlog, "LLW: exit (ignore)\n"); |
3376 | ||
0e5bf2a8 | 3377 | ourstatus->kind = TARGET_WAITKIND_IGNORE; |
28736962 PA |
3378 | restore_child_signals_mask (&prev_mask); |
3379 | return minus_one_ptid; | |
3380 | } | |
d6b0e80f AC |
3381 | |
3382 | /* We shouldn't end up here unless we want to try again. */ | |
d90e17a7 | 3383 | gdb_assert (lp == NULL); |
0e5bf2a8 PA |
3384 | |
3385 | /* Block until we get an event reported with SIGCHLD. */ | |
9c3a5d93 | 3386 | wait_for_signal (); |
d6b0e80f AC |
3387 | } |
3388 | ||
d6b0e80f AC |
3389 | gdb_assert (lp); |
3390 | ||
ca2163eb PA |
3391 | status = lp->status; |
3392 | lp->status = 0; | |
3393 | ||
fbea99ea | 3394 | if (!target_is_non_stop_p ()) |
4c28f408 PA |
3395 | { |
3396 | /* Now stop all other LWP's ... */ | |
d3a70e03 | 3397 | iterate_over_lwps (minus_one_ptid, stop_callback); |
4c28f408 PA |
3398 | |
3399 | /* ... and wait until all of them have reported back that | |
3400 | they're no longer running. */ | |
d3a70e03 | 3401 | iterate_over_lwps (minus_one_ptid, stop_wait_callback); |
9c02b525 PA |
3402 | } |
3403 | ||
3404 | /* If we're not waiting for a specific LWP, choose an event LWP from | |
3405 | among those that have had events. Giving equal priority to all | |
3406 | LWPs that have had events helps prevent starvation. */ | |
d7e15655 | 3407 | if (ptid == minus_one_ptid || ptid.is_pid ()) |
9c02b525 PA |
3408 | select_event_lwp (ptid, &lp, &status); |
3409 | ||
3410 | gdb_assert (lp != NULL); | |
3411 | ||
3412 | /* Now that we've selected our final event LWP, un-adjust its PC if | |
faf09f01 PA |
3413 | it was a software breakpoint, and we can't reliably support the |
3414 | "stopped by software breakpoint" stop reason. */ | |
3415 | if (lp->stop_reason == TARGET_STOPPED_BY_SW_BREAKPOINT | |
3416 | && !USE_SIGTRAP_SIGINFO) | |
9c02b525 PA |
3417 | { |
3418 | struct regcache *regcache = get_thread_regcache (lp->ptid); | |
ac7936df | 3419 | struct gdbarch *gdbarch = regcache->arch (); |
527a273a | 3420 | int decr_pc = gdbarch_decr_pc_after_break (gdbarch); |
4c28f408 | 3421 | |
9c02b525 PA |
3422 | if (decr_pc != 0) |
3423 | { | |
3424 | CORE_ADDR pc; | |
d6b0e80f | 3425 | |
9c02b525 PA |
3426 | pc = regcache_read_pc (regcache); |
3427 | regcache_write_pc (regcache, pc + decr_pc); | |
3428 | } | |
3429 | } | |
e3e9f5a2 | 3430 | |
9c02b525 PA |
3431 | /* We'll need this to determine whether to report a SIGSTOP as |
3432 | GDB_SIGNAL_0. Need to take a copy because resume_clear_callback | |
3433 | clears it. */ | |
3434 | last_resume_kind = lp->last_resume_kind; | |
4b60df3d | 3435 | |
fbea99ea | 3436 | if (!target_is_non_stop_p ()) |
9c02b525 | 3437 | { |
e3e9f5a2 PA |
3438 | /* In all-stop, from the core's perspective, all LWPs are now |
3439 | stopped until a new resume action is sent over. */ | |
d3a70e03 | 3440 | iterate_over_lwps (minus_one_ptid, resume_clear_callback); |
e3e9f5a2 PA |
3441 | } |
3442 | else | |
25289eb2 | 3443 | { |
d3a70e03 | 3444 | resume_clear_callback (lp); |
25289eb2 | 3445 | } |
d6b0e80f | 3446 | |
135340af | 3447 | if (linux_target->low_status_is_event (status)) |
d6b0e80f | 3448 | { |
d6b0e80f AC |
3449 | if (debug_linux_nat) |
3450 | fprintf_unfiltered (gdb_stdlog, | |
4fdebdd0 | 3451 | "LLW: trap ptid is %s.\n", |
a068643d | 3452 | target_pid_to_str (lp->ptid).c_str ()); |
d6b0e80f | 3453 | } |
d6b0e80f AC |
3454 | |
3455 | if (lp->waitstatus.kind != TARGET_WAITKIND_IGNORE) | |
3456 | { | |
3457 | *ourstatus = lp->waitstatus; | |
3458 | lp->waitstatus.kind = TARGET_WAITKIND_IGNORE; | |
3459 | } | |
3460 | else | |
3461 | store_waitstatus (ourstatus, status); | |
3462 | ||
01124a23 | 3463 | if (debug_linux_nat) |
b84876c2 PA |
3464 | fprintf_unfiltered (gdb_stdlog, "LLW: exit\n"); |
3465 | ||
7feb7d06 | 3466 | restore_child_signals_mask (&prev_mask); |
1e225492 | 3467 | |
4b60df3d | 3468 | if (last_resume_kind == resume_stop |
25289eb2 PA |
3469 | && ourstatus->kind == TARGET_WAITKIND_STOPPED |
3470 | && WSTOPSIG (status) == SIGSTOP) | |
3471 | { | |
3472 | /* A thread that has been requested to stop by GDB with | |
3473 | target_stop, and it stopped cleanly, so report as SIG0. The | |
3474 | use of SIGSTOP is an implementation detail. */ | |
a493e3e2 | 3475 | ourstatus->value.sig = GDB_SIGNAL_0; |
25289eb2 PA |
3476 | } |
3477 | ||
1e225492 JK |
3478 | if (ourstatus->kind == TARGET_WAITKIND_EXITED |
3479 | || ourstatus->kind == TARGET_WAITKIND_SIGNALLED) | |
3480 | lp->core = -1; | |
3481 | else | |
2e794194 | 3482 | lp->core = linux_common_core_of_thread (lp->ptid); |
1e225492 | 3483 | |
aa01bd36 PA |
3484 | if (ourstatus->kind == TARGET_WAITKIND_EXITED) |
3485 | return filter_exit_event (lp, ourstatus); | |
3486 | ||
f973ed9c | 3487 | return lp->ptid; |
d6b0e80f AC |
3488 | } |
3489 | ||
e3e9f5a2 PA |
3490 | /* Resume LWPs that are currently stopped without any pending status |
3491 | to report, but are resumed from the core's perspective. */ | |
3492 | ||
3493 | static int | |
d3a70e03 | 3494 | resume_stopped_resumed_lwps (struct lwp_info *lp, const ptid_t wait_ptid) |
e3e9f5a2 | 3495 | { |
4dd63d48 PA |
3496 | if (!lp->stopped) |
3497 | { | |
3498 | if (debug_linux_nat) | |
3499 | fprintf_unfiltered (gdb_stdlog, | |
3500 | "RSRL: NOT resuming LWP %s, not stopped\n", | |
a068643d | 3501 | target_pid_to_str (lp->ptid).c_str ()); |
4dd63d48 PA |
3502 | } |
3503 | else if (!lp->resumed) | |
3504 | { | |
3505 | if (debug_linux_nat) | |
3506 | fprintf_unfiltered (gdb_stdlog, | |
3507 | "RSRL: NOT resuming LWP %s, not resumed\n", | |
a068643d | 3508 | target_pid_to_str (lp->ptid).c_str ()); |
4dd63d48 PA |
3509 | } |
3510 | else if (lwp_status_pending_p (lp)) | |
3511 | { | |
3512 | if (debug_linux_nat) | |
3513 | fprintf_unfiltered (gdb_stdlog, | |
3514 | "RSRL: NOT resuming LWP %s, has pending status\n", | |
a068643d | 3515 | target_pid_to_str (lp->ptid).c_str ()); |
4dd63d48 PA |
3516 | } |
3517 | else | |
e3e9f5a2 | 3518 | { |
336060f3 | 3519 | struct regcache *regcache = get_thread_regcache (lp->ptid); |
ac7936df | 3520 | struct gdbarch *gdbarch = regcache->arch (); |
336060f3 | 3521 | |
a70b8144 | 3522 | try |
e3e9f5a2 | 3523 | { |
23f238d3 PA |
3524 | CORE_ADDR pc = regcache_read_pc (regcache); |
3525 | int leave_stopped = 0; | |
e3e9f5a2 | 3526 | |
23f238d3 PA |
3527 | /* Don't bother if there's a breakpoint at PC that we'd hit |
3528 | immediately, and we're not waiting for this LWP. */ | |
d3a70e03 | 3529 | if (!lp->ptid.matches (wait_ptid)) |
23f238d3 | 3530 | { |
a01bda52 | 3531 | if (breakpoint_inserted_here_p (regcache->aspace (), pc)) |
23f238d3 PA |
3532 | leave_stopped = 1; |
3533 | } | |
e3e9f5a2 | 3534 | |
23f238d3 PA |
3535 | if (!leave_stopped) |
3536 | { | |
3537 | if (debug_linux_nat) | |
3538 | fprintf_unfiltered (gdb_stdlog, | |
3539 | "RSRL: resuming stopped-resumed LWP %s at " | |
3540 | "%s: step=%d\n", | |
a068643d | 3541 | target_pid_to_str (lp->ptid).c_str (), |
23f238d3 PA |
3542 | paddress (gdbarch, pc), |
3543 | lp->step); | |
3544 | ||
3545 | linux_resume_one_lwp_throw (lp, lp->step, GDB_SIGNAL_0); | |
3546 | } | |
3547 | } | |
230d2906 | 3548 | catch (const gdb_exception_error &ex) |
23f238d3 PA |
3549 | { |
3550 | if (!check_ptrace_stopped_lwp_gone (lp)) | |
eedc3f4f | 3551 | throw; |
23f238d3 | 3552 | } |
e3e9f5a2 PA |
3553 | } |
3554 | ||
3555 | return 0; | |
3556 | } | |
3557 | ||
f6ac5f3d PA |
3558 | ptid_t |
3559 | linux_nat_target::wait (ptid_t ptid, struct target_waitstatus *ourstatus, | |
3560 | int target_options) | |
7feb7d06 PA |
3561 | { |
3562 | ptid_t event_ptid; | |
3563 | ||
3564 | if (debug_linux_nat) | |
09826ec5 | 3565 | { |
09ce46f2 | 3566 | std::string options_string = target_options_to_string (target_options); |
09826ec5 PA |
3567 | fprintf_unfiltered (gdb_stdlog, |
3568 | "linux_nat_wait: [%s], [%s]\n", | |
a068643d | 3569 | target_pid_to_str (ptid).c_str (), |
09ce46f2 | 3570 | options_string.c_str ()); |
09826ec5 | 3571 | } |
7feb7d06 PA |
3572 | |
3573 | /* Flush the async file first. */ | |
d9d41e78 | 3574 | if (target_is_async_p ()) |
7feb7d06 PA |
3575 | async_file_flush (); |
3576 | ||
e3e9f5a2 PA |
3577 | /* Resume LWPs that are currently stopped without any pending status |
3578 | to report, but are resumed from the core's perspective. LWPs get | |
3579 | in this state if we find them stopping at a time we're not | |
3580 | interested in reporting the event (target_wait on a | |
3581 | specific_process, for example, see linux_nat_wait_1), and | |
3582 | meanwhile the event became uninteresting. Don't bother resuming | |
3583 | LWPs we're not going to wait for if they'd stop immediately. */ | |
fbea99ea | 3584 | if (target_is_non_stop_p ()) |
d3a70e03 TT |
3585 | iterate_over_lwps (minus_one_ptid, |
3586 | [=] (struct lwp_info *info) | |
3587 | { | |
3588 | return resume_stopped_resumed_lwps (info, ptid); | |
3589 | }); | |
e3e9f5a2 | 3590 | |
f6ac5f3d | 3591 | event_ptid = linux_nat_wait_1 (ptid, ourstatus, target_options); |
7feb7d06 PA |
3592 | |
3593 | /* If we requested any event, and something came out, assume there | |
3594 | may be more. If we requested a specific lwp or process, also | |
3595 | assume there may be more. */ | |
d9d41e78 | 3596 | if (target_is_async_p () |
6953d224 PA |
3597 | && ((ourstatus->kind != TARGET_WAITKIND_IGNORE |
3598 | && ourstatus->kind != TARGET_WAITKIND_NO_RESUMED) | |
d7e15655 | 3599 | || ptid != minus_one_ptid)) |
7feb7d06 PA |
3600 | async_file_mark (); |
3601 | ||
7feb7d06 PA |
3602 | return event_ptid; |
3603 | } | |
3604 | ||
1d2736d4 PA |
3605 | /* Kill one LWP. */ |
3606 | ||
3607 | static void | |
3608 | kill_one_lwp (pid_t pid) | |
d6b0e80f | 3609 | { |
ed731959 JK |
3610 | /* PTRACE_KILL may resume the inferior. Send SIGKILL first. */ |
3611 | ||
3612 | errno = 0; | |
1d2736d4 | 3613 | kill_lwp (pid, SIGKILL); |
ed731959 | 3614 | if (debug_linux_nat) |
57745c90 PA |
3615 | { |
3616 | int save_errno = errno; | |
3617 | ||
3618 | fprintf_unfiltered (gdb_stdlog, | |
1d2736d4 | 3619 | "KC: kill (SIGKILL) %ld, 0, 0 (%s)\n", (long) pid, |
57745c90 PA |
3620 | save_errno ? safe_strerror (save_errno) : "OK"); |
3621 | } | |
ed731959 JK |
3622 | |
3623 | /* Some kernels ignore even SIGKILL for processes under ptrace. */ | |
3624 | ||
d6b0e80f | 3625 | errno = 0; |
1d2736d4 | 3626 | ptrace (PTRACE_KILL, pid, 0, 0); |
d6b0e80f | 3627 | if (debug_linux_nat) |
57745c90 PA |
3628 | { |
3629 | int save_errno = errno; | |
3630 | ||
3631 | fprintf_unfiltered (gdb_stdlog, | |
1d2736d4 | 3632 | "KC: PTRACE_KILL %ld, 0, 0 (%s)\n", (long) pid, |
57745c90 PA |
3633 | save_errno ? safe_strerror (save_errno) : "OK"); |
3634 | } | |
d6b0e80f AC |
3635 | } |
3636 | ||
1d2736d4 PA |
3637 | /* Wait for an LWP to die. */ |
3638 | ||
3639 | static void | |
3640 | kill_wait_one_lwp (pid_t pid) | |
d6b0e80f | 3641 | { |
1d2736d4 | 3642 | pid_t res; |
d6b0e80f AC |
3643 | |
3644 | /* We must make sure that there are no pending events (delayed | |
3645 | SIGSTOPs, pending SIGTRAPs, etc.) to make sure the current | |
3646 | program doesn't interfere with any following debugging session. */ | |
3647 | ||
d6b0e80f AC |
3648 | do |
3649 | { | |
1d2736d4 PA |
3650 | res = my_waitpid (pid, NULL, __WALL); |
3651 | if (res != (pid_t) -1) | |
d6b0e80f | 3652 | { |
e85a822c DJ |
3653 | if (debug_linux_nat) |
3654 | fprintf_unfiltered (gdb_stdlog, | |
1d2736d4 PA |
3655 | "KWC: wait %ld received unknown.\n", |
3656 | (long) pid); | |
4a6ed09b PA |
3657 | /* The Linux kernel sometimes fails to kill a thread |
3658 | completely after PTRACE_KILL; that goes from the stop | |
3659 | point in do_fork out to the one in get_signal_to_deliver | |
3660 | and waits again. So kill it again. */ | |
1d2736d4 | 3661 | kill_one_lwp (pid); |
d6b0e80f AC |
3662 | } |
3663 | } | |
1d2736d4 PA |
3664 | while (res == pid); |
3665 | ||
3666 | gdb_assert (res == -1 && errno == ECHILD); | |
3667 | } | |
3668 | ||
3669 | /* Callback for iterate_over_lwps. */ | |
d6b0e80f | 3670 | |
1d2736d4 | 3671 | static int |
d3a70e03 | 3672 | kill_callback (struct lwp_info *lp) |
1d2736d4 | 3673 | { |
e38504b3 | 3674 | kill_one_lwp (lp->ptid.lwp ()); |
d6b0e80f AC |
3675 | return 0; |
3676 | } | |
3677 | ||
1d2736d4 PA |
3678 | /* Callback for iterate_over_lwps. */ |
3679 | ||
3680 | static int | |
d3a70e03 | 3681 | kill_wait_callback (struct lwp_info *lp) |
1d2736d4 | 3682 | { |
e38504b3 | 3683 | kill_wait_one_lwp (lp->ptid.lwp ()); |
1d2736d4 PA |
3684 | return 0; |
3685 | } | |
3686 | ||
3687 | /* Kill the fork children of any threads of inferior INF that are | |
3688 | stopped at a fork event. */ | |
3689 | ||
3690 | static void | |
3691 | kill_unfollowed_fork_children (struct inferior *inf) | |
3692 | { | |
08036331 PA |
3693 | for (thread_info *thread : inf->non_exited_threads ()) |
3694 | { | |
3695 | struct target_waitstatus *ws = &thread->pending_follow; | |
1d2736d4 | 3696 | |
08036331 PA |
3697 | if (ws->kind == TARGET_WAITKIND_FORKED |
3698 | || ws->kind == TARGET_WAITKIND_VFORKED) | |
3699 | { | |
3700 | ptid_t child_ptid = ws->value.related_pid; | |
3701 | int child_pid = child_ptid.pid (); | |
3702 | int child_lwp = child_ptid.lwp (); | |
3703 | ||
3704 | kill_one_lwp (child_lwp); | |
3705 | kill_wait_one_lwp (child_lwp); | |
3706 | ||
3707 | /* Let the arch-specific native code know this process is | |
3708 | gone. */ | |
3709 | linux_target->low_forget_process (child_pid); | |
3710 | } | |
3711 | } | |
1d2736d4 PA |
3712 | } |
3713 | ||
f6ac5f3d PA |
3714 | void |
3715 | linux_nat_target::kill () | |
d6b0e80f | 3716 | { |
f973ed9c DJ |
3717 | /* If we're stopped while forking and we haven't followed yet, |
3718 | kill the other task. We need to do this first because the | |
3719 | parent will be sleeping if this is a vfork. */ | |
1d2736d4 | 3720 | kill_unfollowed_fork_children (current_inferior ()); |
f973ed9c DJ |
3721 | |
3722 | if (forks_exist_p ()) | |
7feb7d06 | 3723 | linux_fork_killall (); |
f973ed9c DJ |
3724 | else |
3725 | { | |
e99b03dc | 3726 | ptid_t ptid = ptid_t (inferior_ptid.pid ()); |
e0881a8e | 3727 | |
4c28f408 PA |
3728 | /* Stop all threads before killing them, since ptrace requires |
3729 | that the thread is stopped to sucessfully PTRACE_KILL. */ | |
d3a70e03 | 3730 | iterate_over_lwps (ptid, stop_callback); |
4c28f408 PA |
3731 | /* ... and wait until all of them have reported back that |
3732 | they're no longer running. */ | |
d3a70e03 | 3733 | iterate_over_lwps (ptid, stop_wait_callback); |
4c28f408 | 3734 | |
f973ed9c | 3735 | /* Kill all LWP's ... */ |
d3a70e03 | 3736 | iterate_over_lwps (ptid, kill_callback); |
f973ed9c DJ |
3737 | |
3738 | /* ... and wait until we've flushed all events. */ | |
d3a70e03 | 3739 | iterate_over_lwps (ptid, kill_wait_callback); |
f973ed9c DJ |
3740 | } |
3741 | ||
bc1e6c81 | 3742 | target_mourn_inferior (inferior_ptid); |
d6b0e80f AC |
3743 | } |
3744 | ||
f6ac5f3d PA |
3745 | void |
3746 | linux_nat_target::mourn_inferior () | |
d6b0e80f | 3747 | { |
e99b03dc | 3748 | int pid = inferior_ptid.pid (); |
26cb8b7c PA |
3749 | |
3750 | purge_lwp_list (pid); | |
d6b0e80f | 3751 | |
f973ed9c | 3752 | if (! forks_exist_p ()) |
d90e17a7 | 3753 | /* Normal case, no other forks available. */ |
f6ac5f3d | 3754 | inf_ptrace_target::mourn_inferior (); |
f973ed9c DJ |
3755 | else |
3756 | /* Multi-fork case. The current inferior_ptid has exited, but | |
3757 | there are other viable forks to debug. Delete the exiting | |
3758 | one and context-switch to the first available. */ | |
3759 | linux_fork_mourn_inferior (); | |
26cb8b7c PA |
3760 | |
3761 | /* Let the arch-specific native code know this process is gone. */ | |
135340af | 3762 | linux_target->low_forget_process (pid); |
d6b0e80f AC |
3763 | } |
3764 | ||
5b009018 PA |
3765 | /* Convert a native/host siginfo object, into/from the siginfo in the |
3766 | layout of the inferiors' architecture. */ | |
3767 | ||
3768 | static void | |
a5362b9a | 3769 | siginfo_fixup (siginfo_t *siginfo, gdb_byte *inf_siginfo, int direction) |
5b009018 | 3770 | { |
135340af PA |
3771 | /* If the low target didn't do anything, then just do a straight |
3772 | memcpy. */ | |
3773 | if (!linux_target->low_siginfo_fixup (siginfo, inf_siginfo, direction)) | |
5b009018 PA |
3774 | { |
3775 | if (direction == 1) | |
a5362b9a | 3776 | memcpy (siginfo, inf_siginfo, sizeof (siginfo_t)); |
5b009018 | 3777 | else |
a5362b9a | 3778 | memcpy (inf_siginfo, siginfo, sizeof (siginfo_t)); |
5b009018 PA |
3779 | } |
3780 | } | |
3781 | ||
9b409511 | 3782 | static enum target_xfer_status |
f6ac5f3d | 3783 | linux_xfer_siginfo (enum target_object object, |
4aa995e1 | 3784 | const char *annex, gdb_byte *readbuf, |
9b409511 YQ |
3785 | const gdb_byte *writebuf, ULONGEST offset, ULONGEST len, |
3786 | ULONGEST *xfered_len) | |
4aa995e1 | 3787 | { |
4aa995e1 | 3788 | int pid; |
a5362b9a TS |
3789 | siginfo_t siginfo; |
3790 | gdb_byte inf_siginfo[sizeof (siginfo_t)]; | |
4aa995e1 PA |
3791 | |
3792 | gdb_assert (object == TARGET_OBJECT_SIGNAL_INFO); | |
3793 | gdb_assert (readbuf || writebuf); | |
3794 | ||
e38504b3 | 3795 | pid = inferior_ptid.lwp (); |
4aa995e1 | 3796 | if (pid == 0) |
e99b03dc | 3797 | pid = inferior_ptid.pid (); |
4aa995e1 PA |
3798 | |
3799 | if (offset > sizeof (siginfo)) | |
2ed4b548 | 3800 | return TARGET_XFER_E_IO; |
4aa995e1 PA |
3801 | |
3802 | errno = 0; | |
3803 | ptrace (PTRACE_GETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo); | |
3804 | if (errno != 0) | |
2ed4b548 | 3805 | return TARGET_XFER_E_IO; |
4aa995e1 | 3806 | |
5b009018 PA |
3807 | /* When GDB is built as a 64-bit application, ptrace writes into |
3808 | SIGINFO an object with 64-bit layout. Since debugging a 32-bit | |
3809 | inferior with a 64-bit GDB should look the same as debugging it | |
3810 | with a 32-bit GDB, we need to convert it. GDB core always sees | |
3811 | the converted layout, so any read/write will have to be done | |
3812 | post-conversion. */ | |
3813 | siginfo_fixup (&siginfo, inf_siginfo, 0); | |
3814 | ||
4aa995e1 PA |
3815 | if (offset + len > sizeof (siginfo)) |
3816 | len = sizeof (siginfo) - offset; | |
3817 | ||
3818 | if (readbuf != NULL) | |
5b009018 | 3819 | memcpy (readbuf, inf_siginfo + offset, len); |
4aa995e1 PA |
3820 | else |
3821 | { | |
5b009018 PA |
3822 | memcpy (inf_siginfo + offset, writebuf, len); |
3823 | ||
3824 | /* Convert back to ptrace layout before flushing it out. */ | |
3825 | siginfo_fixup (&siginfo, inf_siginfo, 1); | |
3826 | ||
4aa995e1 PA |
3827 | errno = 0; |
3828 | ptrace (PTRACE_SETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, &siginfo); | |
3829 | if (errno != 0) | |
2ed4b548 | 3830 | return TARGET_XFER_E_IO; |
4aa995e1 PA |
3831 | } |
3832 | ||
9b409511 YQ |
3833 | *xfered_len = len; |
3834 | return TARGET_XFER_OK; | |
4aa995e1 PA |
3835 | } |
3836 | ||
9b409511 | 3837 | static enum target_xfer_status |
f6ac5f3d PA |
3838 | linux_nat_xfer_osdata (enum target_object object, |
3839 | const char *annex, gdb_byte *readbuf, | |
3840 | const gdb_byte *writebuf, ULONGEST offset, ULONGEST len, | |
3841 | ULONGEST *xfered_len); | |
3842 | ||
f6ac5f3d PA |
3843 | static enum target_xfer_status |
3844 | linux_proc_xfer_partial (enum target_object object, | |
3845 | const char *annex, gdb_byte *readbuf, | |
3846 | const gdb_byte *writebuf, | |
3847 | ULONGEST offset, LONGEST len, ULONGEST *xfered_len); | |
3848 | ||
3849 | enum target_xfer_status | |
3850 | linux_nat_target::xfer_partial (enum target_object object, | |
3851 | const char *annex, gdb_byte *readbuf, | |
3852 | const gdb_byte *writebuf, | |
3853 | ULONGEST offset, ULONGEST len, ULONGEST *xfered_len) | |
d6b0e80f | 3854 | { |
9b409511 | 3855 | enum target_xfer_status xfer; |
d6b0e80f | 3856 | |
4aa995e1 | 3857 | if (object == TARGET_OBJECT_SIGNAL_INFO) |
f6ac5f3d | 3858 | return linux_xfer_siginfo (object, annex, readbuf, writebuf, |
9b409511 | 3859 | offset, len, xfered_len); |
4aa995e1 | 3860 | |
c35b1492 PA |
3861 | /* The target is connected but no live inferior is selected. Pass |
3862 | this request down to a lower stratum (e.g., the executable | |
3863 | file). */ | |
d7e15655 | 3864 | if (object == TARGET_OBJECT_MEMORY && inferior_ptid == null_ptid) |
9b409511 | 3865 | return TARGET_XFER_EOF; |
c35b1492 | 3866 | |
f6ac5f3d PA |
3867 | if (object == TARGET_OBJECT_AUXV) |
3868 | return memory_xfer_auxv (this, object, annex, readbuf, writebuf, | |
3869 | offset, len, xfered_len); | |
3870 | ||
3871 | if (object == TARGET_OBJECT_OSDATA) | |
3872 | return linux_nat_xfer_osdata (object, annex, readbuf, writebuf, | |
3873 | offset, len, xfered_len); | |
d6b0e80f | 3874 | |
f6ac5f3d PA |
3875 | /* GDB calculates all addresses in the largest possible address |
3876 | width. | |
3877 | The address width must be masked before its final use - either by | |
3878 | linux_proc_xfer_partial or inf_ptrace_target::xfer_partial. | |
3879 | ||
3880 | Compare ADDR_BIT first to avoid a compiler warning on shift overflow. */ | |
3881 | ||
3882 | if (object == TARGET_OBJECT_MEMORY) | |
3883 | { | |
3884 | int addr_bit = gdbarch_addr_bit (target_gdbarch ()); | |
3885 | ||
3886 | if (addr_bit < (sizeof (ULONGEST) * HOST_CHAR_BIT)) | |
3887 | offset &= ((ULONGEST) 1 << addr_bit) - 1; | |
3888 | } | |
3889 | ||
3890 | xfer = linux_proc_xfer_partial (object, annex, readbuf, writebuf, | |
3891 | offset, len, xfered_len); | |
3892 | if (xfer != TARGET_XFER_EOF) | |
3893 | return xfer; | |
3894 | ||
3895 | return inf_ptrace_target::xfer_partial (object, annex, readbuf, writebuf, | |
3896 | offset, len, xfered_len); | |
d6b0e80f AC |
3897 | } |
3898 | ||
57810aa7 | 3899 | bool |
f6ac5f3d | 3900 | linux_nat_target::thread_alive (ptid_t ptid) |
28439f5e | 3901 | { |
4a6ed09b PA |
3902 | /* As long as a PTID is in lwp list, consider it alive. */ |
3903 | return find_lwp_pid (ptid) != NULL; | |
28439f5e PA |
3904 | } |
3905 | ||
8a06aea7 PA |
3906 | /* Implement the to_update_thread_list target method for this |
3907 | target. */ | |
3908 | ||
f6ac5f3d PA |
3909 | void |
3910 | linux_nat_target::update_thread_list () | |
8a06aea7 | 3911 | { |
a6904d5a PA |
3912 | struct lwp_info *lwp; |
3913 | ||
4a6ed09b PA |
3914 | /* We add/delete threads from the list as clone/exit events are |
3915 | processed, so just try deleting exited threads still in the | |
3916 | thread list. */ | |
3917 | delete_exited_threads (); | |
a6904d5a PA |
3918 | |
3919 | /* Update the processor core that each lwp/thread was last seen | |
3920 | running on. */ | |
3921 | ALL_LWPS (lwp) | |
1ad3de98 PA |
3922 | { |
3923 | /* Avoid accessing /proc if the thread hasn't run since we last | |
3924 | time we fetched the thread's core. Accessing /proc becomes | |
3925 | noticeably expensive when we have thousands of LWPs. */ | |
3926 | if (lwp->core == -1) | |
3927 | lwp->core = linux_common_core_of_thread (lwp->ptid); | |
3928 | } | |
8a06aea7 PA |
3929 | } |
3930 | ||
a068643d | 3931 | std::string |
f6ac5f3d | 3932 | linux_nat_target::pid_to_str (ptid_t ptid) |
d6b0e80f | 3933 | { |
15a9e13e | 3934 | if (ptid.lwp_p () |
e38504b3 | 3935 | && (ptid.pid () != ptid.lwp () |
e99b03dc | 3936 | || num_lwps (ptid.pid ()) > 1)) |
a068643d | 3937 | return string_printf ("LWP %ld", ptid.lwp ()); |
d6b0e80f AC |
3938 | |
3939 | return normal_pid_to_str (ptid); | |
3940 | } | |
3941 | ||
f6ac5f3d PA |
3942 | const char * |
3943 | linux_nat_target::thread_name (struct thread_info *thr) | |
4694da01 | 3944 | { |
79efa585 | 3945 | return linux_proc_tid_get_name (thr->ptid); |
4694da01 TT |
3946 | } |
3947 | ||
dba24537 AC |
3948 | /* Accepts an integer PID; Returns a string representing a file that |
3949 | can be opened to get the symbols for the child process. */ | |
3950 | ||
f6ac5f3d PA |
3951 | char * |
3952 | linux_nat_target::pid_to_exec_file (int pid) | |
dba24537 | 3953 | { |
e0d86d2c | 3954 | return linux_proc_pid_to_exec_file (pid); |
dba24537 AC |
3955 | } |
3956 | ||
a379284a AA |
3957 | /* Implement the to_xfer_partial target method using /proc/<pid>/mem. |
3958 | Because we can use a single read/write call, this can be much more | |
3959 | efficient than banging away at PTRACE_PEEKTEXT. */ | |
10d6c8cd | 3960 | |
9b409511 | 3961 | static enum target_xfer_status |
f6ac5f3d | 3962 | linux_proc_xfer_partial (enum target_object object, |
10d6c8cd DJ |
3963 | const char *annex, gdb_byte *readbuf, |
3964 | const gdb_byte *writebuf, | |
9b409511 | 3965 | ULONGEST offset, LONGEST len, ULONGEST *xfered_len) |
dba24537 | 3966 | { |
10d6c8cd DJ |
3967 | LONGEST ret; |
3968 | int fd; | |
dba24537 AC |
3969 | char filename[64]; |
3970 | ||
a379284a | 3971 | if (object != TARGET_OBJECT_MEMORY) |
f486487f | 3972 | return TARGET_XFER_EOF; |
dba24537 AC |
3973 | |
3974 | /* Don't bother for one word. */ | |
3975 | if (len < 3 * sizeof (long)) | |
9b409511 | 3976 | return TARGET_XFER_EOF; |
dba24537 AC |
3977 | |
3978 | /* We could keep this file open and cache it - possibly one per | |
3979 | thread. That requires some juggling, but is even faster. */ | |
b67aeab0 | 3980 | xsnprintf (filename, sizeof filename, "/proc/%ld/mem", |
e38504b3 | 3981 | inferior_ptid.lwp ()); |
a379284a AA |
3982 | fd = gdb_open_cloexec (filename, ((readbuf ? O_RDONLY : O_WRONLY) |
3983 | | O_LARGEFILE), 0); | |
dba24537 | 3984 | if (fd == -1) |
9b409511 | 3985 | return TARGET_XFER_EOF; |
dba24537 | 3986 | |
a379284a AA |
3987 | /* Use pread64/pwrite64 if available, since they save a syscall and can |
3988 | handle 64-bit offsets even on 32-bit platforms (for instance, SPARC | |
3989 | debugging a SPARC64 application). */ | |
dba24537 | 3990 | #ifdef HAVE_PREAD64 |
a379284a AA |
3991 | ret = (readbuf ? pread64 (fd, readbuf, len, offset) |
3992 | : pwrite64 (fd, writebuf, len, offset)); | |
dba24537 | 3993 | #else |
a379284a AA |
3994 | ret = lseek (fd, offset, SEEK_SET); |
3995 | if (ret != -1) | |
3996 | ret = (readbuf ? read (fd, readbuf, len) | |
3997 | : write (fd, writebuf, len)); | |
dba24537 | 3998 | #endif |
dba24537 AC |
3999 | |
4000 | close (fd); | |
9b409511 | 4001 | |
a379284a | 4002 | if (ret == -1 || ret == 0) |
9b409511 YQ |
4003 | return TARGET_XFER_EOF; |
4004 | else | |
4005 | { | |
4006 | *xfered_len = ret; | |
4007 | return TARGET_XFER_OK; | |
4008 | } | |
dba24537 AC |
4009 | } |
4010 | ||
efcbbd14 | 4011 | |
dba24537 AC |
4012 | /* Parse LINE as a signal set and add its set bits to SIGS. */ |
4013 | ||
4014 | static void | |
4015 | add_line_to_sigset (const char *line, sigset_t *sigs) | |
4016 | { | |
4017 | int len = strlen (line) - 1; | |
4018 | const char *p; | |
4019 | int signum; | |
4020 | ||
4021 | if (line[len] != '\n') | |
8a3fe4f8 | 4022 | error (_("Could not parse signal set: %s"), line); |
dba24537 AC |
4023 | |
4024 | p = line; | |
4025 | signum = len * 4; | |
4026 | while (len-- > 0) | |
4027 | { | |
4028 | int digit; | |
4029 | ||
4030 | if (*p >= '0' && *p <= '9') | |
4031 | digit = *p - '0'; | |
4032 | else if (*p >= 'a' && *p <= 'f') | |
4033 | digit = *p - 'a' + 10; | |
4034 | else | |
8a3fe4f8 | 4035 | error (_("Could not parse signal set: %s"), line); |
dba24537 AC |
4036 | |
4037 | signum -= 4; | |
4038 | ||
4039 | if (digit & 1) | |
4040 | sigaddset (sigs, signum + 1); | |
4041 | if (digit & 2) | |
4042 | sigaddset (sigs, signum + 2); | |
4043 | if (digit & 4) | |
4044 | sigaddset (sigs, signum + 3); | |
4045 | if (digit & 8) | |
4046 | sigaddset (sigs, signum + 4); | |
4047 | ||
4048 | p++; | |
4049 | } | |
4050 | } | |
4051 | ||
4052 | /* Find process PID's pending signals from /proc/pid/status and set | |
4053 | SIGS to match. */ | |
4054 | ||
4055 | void | |
3e43a32a MS |
4056 | linux_proc_pending_signals (int pid, sigset_t *pending, |
4057 | sigset_t *blocked, sigset_t *ignored) | |
dba24537 | 4058 | { |
d8d2a3ee | 4059 | char buffer[PATH_MAX], fname[PATH_MAX]; |
dba24537 AC |
4060 | |
4061 | sigemptyset (pending); | |
4062 | sigemptyset (blocked); | |
4063 | sigemptyset (ignored); | |
cde33bf1 | 4064 | xsnprintf (fname, sizeof fname, "/proc/%d/status", pid); |
d419f42d | 4065 | gdb_file_up procfile = gdb_fopen_cloexec (fname, "r"); |
dba24537 | 4066 | if (procfile == NULL) |
8a3fe4f8 | 4067 | error (_("Could not open %s"), fname); |
dba24537 | 4068 | |
d419f42d | 4069 | while (fgets (buffer, PATH_MAX, procfile.get ()) != NULL) |
dba24537 AC |
4070 | { |
4071 | /* Normal queued signals are on the SigPnd line in the status | |
4072 | file. However, 2.6 kernels also have a "shared" pending | |
4073 | queue for delivering signals to a thread group, so check for | |
4074 | a ShdPnd line also. | |
4075 | ||
4076 | Unfortunately some Red Hat kernels include the shared pending | |
4077 | queue but not the ShdPnd status field. */ | |
4078 | ||
61012eef | 4079 | if (startswith (buffer, "SigPnd:\t")) |
dba24537 | 4080 | add_line_to_sigset (buffer + 8, pending); |
61012eef | 4081 | else if (startswith (buffer, "ShdPnd:\t")) |
dba24537 | 4082 | add_line_to_sigset (buffer + 8, pending); |
61012eef | 4083 | else if (startswith (buffer, "SigBlk:\t")) |
dba24537 | 4084 | add_line_to_sigset (buffer + 8, blocked); |
61012eef | 4085 | else if (startswith (buffer, "SigIgn:\t")) |
dba24537 AC |
4086 | add_line_to_sigset (buffer + 8, ignored); |
4087 | } | |
dba24537 AC |
4088 | } |
4089 | ||
9b409511 | 4090 | static enum target_xfer_status |
f6ac5f3d | 4091 | linux_nat_xfer_osdata (enum target_object object, |
e0881a8e | 4092 | const char *annex, gdb_byte *readbuf, |
9b409511 YQ |
4093 | const gdb_byte *writebuf, ULONGEST offset, ULONGEST len, |
4094 | ULONGEST *xfered_len) | |
07e059b5 | 4095 | { |
07e059b5 VP |
4096 | gdb_assert (object == TARGET_OBJECT_OSDATA); |
4097 | ||
9b409511 YQ |
4098 | *xfered_len = linux_common_xfer_osdata (annex, readbuf, offset, len); |
4099 | if (*xfered_len == 0) | |
4100 | return TARGET_XFER_EOF; | |
4101 | else | |
4102 | return TARGET_XFER_OK; | |
07e059b5 VP |
4103 | } |
4104 | ||
f6ac5f3d PA |
4105 | std::vector<static_tracepoint_marker> |
4106 | linux_nat_target::static_tracepoint_markers_by_strid (const char *strid) | |
5808517f YQ |
4107 | { |
4108 | char s[IPA_CMD_BUF_SIZE]; | |
e99b03dc | 4109 | int pid = inferior_ptid.pid (); |
5d9310c4 | 4110 | std::vector<static_tracepoint_marker> markers; |
256642e8 | 4111 | const char *p = s; |
fd79271b | 4112 | ptid_t ptid = ptid_t (pid, 0, 0); |
5d9310c4 | 4113 | static_tracepoint_marker marker; |
5808517f YQ |
4114 | |
4115 | /* Pause all */ | |
4116 | target_stop (ptid); | |
4117 | ||
4118 | memcpy (s, "qTfSTM", sizeof ("qTfSTM")); | |
4119 | s[sizeof ("qTfSTM")] = 0; | |
4120 | ||
42476b70 | 4121 | agent_run_command (pid, s, strlen (s) + 1); |
5808517f | 4122 | |
1db93f14 TT |
4123 | /* Unpause all. */ |
4124 | SCOPE_EXIT { target_continue_no_signal (ptid); }; | |
5808517f YQ |
4125 | |
4126 | while (*p++ == 'm') | |
4127 | { | |
5808517f YQ |
4128 | do |
4129 | { | |
5d9310c4 | 4130 | parse_static_tracepoint_marker_definition (p, &p, &marker); |
5808517f | 4131 | |
5d9310c4 SM |
4132 | if (strid == NULL || marker.str_id == strid) |
4133 | markers.push_back (std::move (marker)); | |
5808517f YQ |
4134 | } |
4135 | while (*p++ == ','); /* comma-separated list */ | |
4136 | ||
4137 | memcpy (s, "qTsSTM", sizeof ("qTsSTM")); | |
4138 | s[sizeof ("qTsSTM")] = 0; | |
42476b70 | 4139 | agent_run_command (pid, s, strlen (s) + 1); |
5808517f YQ |
4140 | p = s; |
4141 | } | |
4142 | ||
5808517f YQ |
4143 | return markers; |
4144 | } | |
4145 | ||
b84876c2 PA |
4146 | /* target_is_async_p implementation. */ |
4147 | ||
57810aa7 | 4148 | bool |
f6ac5f3d | 4149 | linux_nat_target::is_async_p () |
b84876c2 | 4150 | { |
198297aa | 4151 | return linux_is_async_p (); |
b84876c2 PA |
4152 | } |
4153 | ||
4154 | /* target_can_async_p implementation. */ | |
4155 | ||
57810aa7 | 4156 | bool |
f6ac5f3d | 4157 | linux_nat_target::can_async_p () |
b84876c2 | 4158 | { |
fde1b17d SM |
4159 | /* We're always async, unless the user explicitly prevented it with the |
4160 | "maint set target-async" command. */ | |
3dd5b83d | 4161 | return target_async_permitted; |
b84876c2 PA |
4162 | } |
4163 | ||
57810aa7 | 4164 | bool |
f6ac5f3d | 4165 | linux_nat_target::supports_non_stop () |
9908b566 VP |
4166 | { |
4167 | return 1; | |
4168 | } | |
4169 | ||
fbea99ea PA |
4170 | /* to_always_non_stop_p implementation. */ |
4171 | ||
57810aa7 | 4172 | bool |
f6ac5f3d | 4173 | linux_nat_target::always_non_stop_p () |
fbea99ea | 4174 | { |
f12899e9 | 4175 | return 1; |
fbea99ea PA |
4176 | } |
4177 | ||
d90e17a7 PA |
4178 | /* True if we want to support multi-process. To be removed when GDB |
4179 | supports multi-exec. */ | |
4180 | ||
2277426b | 4181 | int linux_multi_process = 1; |
d90e17a7 | 4182 | |
57810aa7 | 4183 | bool |
f6ac5f3d | 4184 | linux_nat_target::supports_multi_process () |
d90e17a7 PA |
4185 | { |
4186 | return linux_multi_process; | |
4187 | } | |
4188 | ||
57810aa7 | 4189 | bool |
f6ac5f3d | 4190 | linux_nat_target::supports_disable_randomization () |
03583c20 UW |
4191 | { |
4192 | #ifdef HAVE_PERSONALITY | |
4193 | return 1; | |
4194 | #else | |
4195 | return 0; | |
4196 | #endif | |
4197 | } | |
4198 | ||
7feb7d06 PA |
4199 | /* SIGCHLD handler that serves two purposes: In non-stop/async mode, |
4200 | so we notice when any child changes state, and notify the | |
4201 | event-loop; it allows us to use sigsuspend in linux_nat_wait_1 | |
4202 | above to wait for the arrival of a SIGCHLD. */ | |
4203 | ||
b84876c2 | 4204 | static void |
7feb7d06 | 4205 | sigchld_handler (int signo) |
b84876c2 | 4206 | { |
7feb7d06 PA |
4207 | int old_errno = errno; |
4208 | ||
01124a23 DE |
4209 | if (debug_linux_nat) |
4210 | ui_file_write_async_safe (gdb_stdlog, | |
4211 | "sigchld\n", sizeof ("sigchld\n") - 1); | |
7feb7d06 PA |
4212 | |
4213 | if (signo == SIGCHLD | |
4214 | && linux_nat_event_pipe[0] != -1) | |
4215 | async_file_mark (); /* Let the event loop know that there are | |
4216 | events to handle. */ | |
4217 | ||
4218 | errno = old_errno; | |
4219 | } | |
4220 | ||
4221 | /* Callback registered with the target events file descriptor. */ | |
4222 | ||
4223 | static void | |
4224 | handle_target_event (int error, gdb_client_data client_data) | |
4225 | { | |
6a3753b3 | 4226 | inferior_event_handler (INF_REG_EVENT, NULL); |
7feb7d06 PA |
4227 | } |
4228 | ||
4229 | /* Create/destroy the target events pipe. Returns previous state. */ | |
4230 | ||
4231 | static int | |
4232 | linux_async_pipe (int enable) | |
4233 | { | |
198297aa | 4234 | int previous = linux_is_async_p (); |
7feb7d06 PA |
4235 | |
4236 | if (previous != enable) | |
4237 | { | |
4238 | sigset_t prev_mask; | |
4239 | ||
12696c10 PA |
4240 | /* Block child signals while we create/destroy the pipe, as |
4241 | their handler writes to it. */ | |
7feb7d06 PA |
4242 | block_child_signals (&prev_mask); |
4243 | ||
4244 | if (enable) | |
4245 | { | |
614c279d | 4246 | if (gdb_pipe_cloexec (linux_nat_event_pipe) == -1) |
7feb7d06 PA |
4247 | internal_error (__FILE__, __LINE__, |
4248 | "creating event pipe failed."); | |
4249 | ||
4250 | fcntl (linux_nat_event_pipe[0], F_SETFL, O_NONBLOCK); | |
4251 | fcntl (linux_nat_event_pipe[1], F_SETFL, O_NONBLOCK); | |
4252 | } | |
4253 | else | |
4254 | { | |
4255 | close (linux_nat_event_pipe[0]); | |
4256 | close (linux_nat_event_pipe[1]); | |
4257 | linux_nat_event_pipe[0] = -1; | |
4258 | linux_nat_event_pipe[1] = -1; | |
4259 | } | |
4260 | ||
4261 | restore_child_signals_mask (&prev_mask); | |
4262 | } | |
4263 | ||
4264 | return previous; | |
b84876c2 PA |
4265 | } |
4266 | ||
4267 | /* target_async implementation. */ | |
4268 | ||
f6ac5f3d PA |
4269 | void |
4270 | linux_nat_target::async (int enable) | |
b84876c2 | 4271 | { |
6a3753b3 | 4272 | if (enable) |
b84876c2 | 4273 | { |
7feb7d06 PA |
4274 | if (!linux_async_pipe (1)) |
4275 | { | |
4276 | add_file_handler (linux_nat_event_pipe[0], | |
4277 | handle_target_event, NULL); | |
4278 | /* There may be pending events to handle. Tell the event loop | |
4279 | to poll them. */ | |
4280 | async_file_mark (); | |
4281 | } | |
b84876c2 PA |
4282 | } |
4283 | else | |
4284 | { | |
b84876c2 | 4285 | delete_file_handler (linux_nat_event_pipe[0]); |
7feb7d06 | 4286 | linux_async_pipe (0); |
b84876c2 PA |
4287 | } |
4288 | return; | |
4289 | } | |
4290 | ||
a493e3e2 | 4291 | /* Stop an LWP, and push a GDB_SIGNAL_0 stop status if no other |
252fbfc8 PA |
4292 | event came out. */ |
4293 | ||
4c28f408 | 4294 | static int |
d3a70e03 | 4295 | linux_nat_stop_lwp (struct lwp_info *lwp) |
4c28f408 | 4296 | { |
d90e17a7 | 4297 | if (!lwp->stopped) |
252fbfc8 | 4298 | { |
d90e17a7 PA |
4299 | if (debug_linux_nat) |
4300 | fprintf_unfiltered (gdb_stdlog, | |
4301 | "LNSL: running -> suspending %s\n", | |
a068643d | 4302 | target_pid_to_str (lwp->ptid).c_str ()); |
252fbfc8 | 4303 | |
252fbfc8 | 4304 | |
25289eb2 PA |
4305 | if (lwp->last_resume_kind == resume_stop) |
4306 | { | |
4307 | if (debug_linux_nat) | |
4308 | fprintf_unfiltered (gdb_stdlog, | |
4309 | "linux-nat: already stopping LWP %ld at " | |
4310 | "GDB's request\n", | |
e38504b3 | 4311 | lwp->ptid.lwp ()); |
25289eb2 PA |
4312 | return 0; |
4313 | } | |
252fbfc8 | 4314 | |
d3a70e03 | 4315 | stop_callback (lwp); |
25289eb2 | 4316 | lwp->last_resume_kind = resume_stop; |
d90e17a7 PA |
4317 | } |
4318 | else | |
4319 | { | |
4320 | /* Already known to be stopped; do nothing. */ | |
252fbfc8 | 4321 | |
d90e17a7 PA |
4322 | if (debug_linux_nat) |
4323 | { | |
e09875d4 | 4324 | if (find_thread_ptid (lwp->ptid)->stop_requested) |
3e43a32a MS |
4325 | fprintf_unfiltered (gdb_stdlog, |
4326 | "LNSL: already stopped/stop_requested %s\n", | |
a068643d | 4327 | target_pid_to_str (lwp->ptid).c_str ()); |
d90e17a7 | 4328 | else |
3e43a32a MS |
4329 | fprintf_unfiltered (gdb_stdlog, |
4330 | "LNSL: already stopped/no " | |
4331 | "stop_requested yet %s\n", | |
a068643d | 4332 | target_pid_to_str (lwp->ptid).c_str ()); |
252fbfc8 PA |
4333 | } |
4334 | } | |
4c28f408 PA |
4335 | return 0; |
4336 | } | |
4337 | ||
f6ac5f3d PA |
4338 | void |
4339 | linux_nat_target::stop (ptid_t ptid) | |
4c28f408 | 4340 | { |
d3a70e03 | 4341 | iterate_over_lwps (ptid, linux_nat_stop_lwp); |
bfedc46a PA |
4342 | } |
4343 | ||
f6ac5f3d PA |
4344 | void |
4345 | linux_nat_target::close () | |
d90e17a7 PA |
4346 | { |
4347 | /* Unregister from the event loop. */ | |
f6ac5f3d PA |
4348 | if (is_async_p ()) |
4349 | async (0); | |
d90e17a7 | 4350 | |
f6ac5f3d | 4351 | inf_ptrace_target::close (); |
d90e17a7 PA |
4352 | } |
4353 | ||
c0694254 PA |
4354 | /* When requests are passed down from the linux-nat layer to the |
4355 | single threaded inf-ptrace layer, ptids of (lwpid,0,0) form are | |
4356 | used. The address space pointer is stored in the inferior object, | |
4357 | but the common code that is passed such ptid can't tell whether | |
4358 | lwpid is a "main" process id or not (it assumes so). We reverse | |
4359 | look up the "main" process id from the lwp here. */ | |
4360 | ||
f6ac5f3d PA |
4361 | struct address_space * |
4362 | linux_nat_target::thread_address_space (ptid_t ptid) | |
c0694254 PA |
4363 | { |
4364 | struct lwp_info *lwp; | |
4365 | struct inferior *inf; | |
4366 | int pid; | |
4367 | ||
e38504b3 | 4368 | if (ptid.lwp () == 0) |
c0694254 PA |
4369 | { |
4370 | /* An (lwpid,0,0) ptid. Look up the lwp object to get at the | |
4371 | tgid. */ | |
4372 | lwp = find_lwp_pid (ptid); | |
e99b03dc | 4373 | pid = lwp->ptid.pid (); |
c0694254 PA |
4374 | } |
4375 | else | |
4376 | { | |
4377 | /* A (pid,lwpid,0) ptid. */ | |
e99b03dc | 4378 | pid = ptid.pid (); |
c0694254 PA |
4379 | } |
4380 | ||
4381 | inf = find_inferior_pid (pid); | |
4382 | gdb_assert (inf != NULL); | |
4383 | return inf->aspace; | |
4384 | } | |
4385 | ||
dc146f7c VP |
4386 | /* Return the cached value of the processor core for thread PTID. */ |
4387 | ||
f6ac5f3d PA |
4388 | int |
4389 | linux_nat_target::core_of_thread (ptid_t ptid) | |
dc146f7c VP |
4390 | { |
4391 | struct lwp_info *info = find_lwp_pid (ptid); | |
e0881a8e | 4392 | |
dc146f7c VP |
4393 | if (info) |
4394 | return info->core; | |
4395 | return -1; | |
4396 | } | |
4397 | ||
7a6a1731 GB |
4398 | /* Implementation of to_filesystem_is_local. */ |
4399 | ||
57810aa7 | 4400 | bool |
f6ac5f3d | 4401 | linux_nat_target::filesystem_is_local () |
7a6a1731 GB |
4402 | { |
4403 | struct inferior *inf = current_inferior (); | |
4404 | ||
4405 | if (inf->fake_pid_p || inf->pid == 0) | |
57810aa7 | 4406 | return true; |
7a6a1731 GB |
4407 | |
4408 | return linux_ns_same (inf->pid, LINUX_NS_MNT); | |
4409 | } | |
4410 | ||
4411 | /* Convert the INF argument passed to a to_fileio_* method | |
4412 | to a process ID suitable for passing to its corresponding | |
4413 | linux_mntns_* function. If INF is non-NULL then the | |
4414 | caller is requesting the filesystem seen by INF. If INF | |
4415 | is NULL then the caller is requesting the filesystem seen | |
4416 | by the GDB. We fall back to GDB's filesystem in the case | |
4417 | that INF is non-NULL but its PID is unknown. */ | |
4418 | ||
4419 | static pid_t | |
4420 | linux_nat_fileio_pid_of (struct inferior *inf) | |
4421 | { | |
4422 | if (inf == NULL || inf->fake_pid_p || inf->pid == 0) | |
4423 | return getpid (); | |
4424 | else | |
4425 | return inf->pid; | |
4426 | } | |
4427 | ||
4428 | /* Implementation of to_fileio_open. */ | |
4429 | ||
f6ac5f3d PA |
4430 | int |
4431 | linux_nat_target::fileio_open (struct inferior *inf, const char *filename, | |
4432 | int flags, int mode, int warn_if_slow, | |
4433 | int *target_errno) | |
7a6a1731 GB |
4434 | { |
4435 | int nat_flags; | |
4436 | mode_t nat_mode; | |
4437 | int fd; | |
4438 | ||
4439 | if (fileio_to_host_openflags (flags, &nat_flags) == -1 | |
4440 | || fileio_to_host_mode (mode, &nat_mode) == -1) | |
4441 | { | |
4442 | *target_errno = FILEIO_EINVAL; | |
4443 | return -1; | |
4444 | } | |
4445 | ||
4446 | fd = linux_mntns_open_cloexec (linux_nat_fileio_pid_of (inf), | |
4447 | filename, nat_flags, nat_mode); | |
4448 | if (fd == -1) | |
4449 | *target_errno = host_to_fileio_error (errno); | |
4450 | ||
4451 | return fd; | |
4452 | } | |
4453 | ||
4454 | /* Implementation of to_fileio_readlink. */ | |
4455 | ||
f6ac5f3d PA |
4456 | gdb::optional<std::string> |
4457 | linux_nat_target::fileio_readlink (struct inferior *inf, const char *filename, | |
4458 | int *target_errno) | |
7a6a1731 GB |
4459 | { |
4460 | char buf[PATH_MAX]; | |
4461 | int len; | |
7a6a1731 GB |
4462 | |
4463 | len = linux_mntns_readlink (linux_nat_fileio_pid_of (inf), | |
4464 | filename, buf, sizeof (buf)); | |
4465 | if (len < 0) | |
4466 | { | |
4467 | *target_errno = host_to_fileio_error (errno); | |
e0d3522b | 4468 | return {}; |
7a6a1731 GB |
4469 | } |
4470 | ||
e0d3522b | 4471 | return std::string (buf, len); |
7a6a1731 GB |
4472 | } |
4473 | ||
4474 | /* Implementation of to_fileio_unlink. */ | |
4475 | ||
f6ac5f3d PA |
4476 | int |
4477 | linux_nat_target::fileio_unlink (struct inferior *inf, const char *filename, | |
4478 | int *target_errno) | |
7a6a1731 GB |
4479 | { |
4480 | int ret; | |
4481 | ||
4482 | ret = linux_mntns_unlink (linux_nat_fileio_pid_of (inf), | |
4483 | filename); | |
4484 | if (ret == -1) | |
4485 | *target_errno = host_to_fileio_error (errno); | |
4486 | ||
4487 | return ret; | |
4488 | } | |
4489 | ||
aa01bd36 PA |
4490 | /* Implementation of the to_thread_events method. */ |
4491 | ||
f6ac5f3d PA |
4492 | void |
4493 | linux_nat_target::thread_events (int enable) | |
aa01bd36 PA |
4494 | { |
4495 | report_thread_events = enable; | |
4496 | } | |
4497 | ||
f6ac5f3d PA |
4498 | linux_nat_target::linux_nat_target () |
4499 | { | |
f973ed9c DJ |
4500 | /* We don't change the stratum; this target will sit at |
4501 | process_stratum and thread_db will set at thread_stratum. This | |
4502 | is a little strange, since this is a multi-threaded-capable | |
4503 | target, but we want to be on the stack below thread_db, and we | |
4504 | also want to be used for single-threaded processes. */ | |
f973ed9c DJ |
4505 | } |
4506 | ||
f865ee35 JK |
4507 | /* See linux-nat.h. */ |
4508 | ||
4509 | int | |
4510 | linux_nat_get_siginfo (ptid_t ptid, siginfo_t *siginfo) | |
9f0bdab8 | 4511 | { |
da559b09 | 4512 | int pid; |
9f0bdab8 | 4513 | |
e38504b3 | 4514 | pid = ptid.lwp (); |
da559b09 | 4515 | if (pid == 0) |
e99b03dc | 4516 | pid = ptid.pid (); |
f865ee35 | 4517 | |
da559b09 JK |
4518 | errno = 0; |
4519 | ptrace (PTRACE_GETSIGINFO, pid, (PTRACE_TYPE_ARG3) 0, siginfo); | |
4520 | if (errno != 0) | |
4521 | { | |
4522 | memset (siginfo, 0, sizeof (*siginfo)); | |
4523 | return 0; | |
4524 | } | |
f865ee35 | 4525 | return 1; |
9f0bdab8 DJ |
4526 | } |
4527 | ||
7b669087 GB |
4528 | /* See nat/linux-nat.h. */ |
4529 | ||
4530 | ptid_t | |
4531 | current_lwp_ptid (void) | |
4532 | { | |
15a9e13e | 4533 | gdb_assert (inferior_ptid.lwp_p ()); |
7b669087 GB |
4534 | return inferior_ptid; |
4535 | } | |
4536 | ||
d6b0e80f AC |
4537 | void |
4538 | _initialize_linux_nat (void) | |
4539 | { | |
ccce17b0 YQ |
4540 | add_setshow_zuinteger_cmd ("lin-lwp", class_maintenance, |
4541 | &debug_linux_nat, _("\ | |
b84876c2 PA |
4542 | Set debugging of GNU/Linux lwp module."), _("\ |
4543 | Show debugging of GNU/Linux lwp module."), _("\ | |
4544 | Enables printf debugging output."), | |
ccce17b0 YQ |
4545 | NULL, |
4546 | show_debug_linux_nat, | |
4547 | &setdebuglist, &showdebuglist); | |
b84876c2 | 4548 | |
7a6a1731 GB |
4549 | add_setshow_boolean_cmd ("linux-namespaces", class_maintenance, |
4550 | &debug_linux_namespaces, _("\ | |
4551 | Set debugging of GNU/Linux namespaces module."), _("\ | |
4552 | Show debugging of GNU/Linux namespaces module."), _("\ | |
4553 | Enables printf debugging output."), | |
4554 | NULL, | |
4555 | NULL, | |
4556 | &setdebuglist, &showdebuglist); | |
4557 | ||
7feb7d06 PA |
4558 | /* Install a SIGCHLD handler. */ |
4559 | sigchld_action.sa_handler = sigchld_handler; | |
4560 | sigemptyset (&sigchld_action.sa_mask); | |
4561 | sigchld_action.sa_flags = SA_RESTART; | |
b84876c2 PA |
4562 | |
4563 | /* Make it the default. */ | |
7feb7d06 | 4564 | sigaction (SIGCHLD, &sigchld_action, NULL); |
d6b0e80f AC |
4565 | |
4566 | /* Make sure we don't block SIGCHLD during a sigsuspend. */ | |
4567 | sigprocmask (SIG_SETMASK, NULL, &suspend_mask); | |
4568 | sigdelset (&suspend_mask, SIGCHLD); | |
4569 | ||
7feb7d06 | 4570 | sigemptyset (&blocked_mask); |
774113b0 PA |
4571 | |
4572 | lwp_lwpid_htab_create (); | |
d6b0e80f AC |
4573 | } |
4574 | \f | |
4575 | ||
4576 | /* FIXME: kettenis/2000-08-26: The stuff on this page is specific to | |
4577 | the GNU/Linux Threads library and therefore doesn't really belong | |
4578 | here. */ | |
4579 | ||
d6b0e80f AC |
4580 | /* Return the set of signals used by the threads library in *SET. */ |
4581 | ||
4582 | void | |
4583 | lin_thread_get_thread_signals (sigset_t *set) | |
4584 | { | |
d6b0e80f AC |
4585 | sigemptyset (set); |
4586 | ||
4a6ed09b PA |
4587 | /* NPTL reserves the first two RT signals, but does not provide any |
4588 | way for the debugger to query the signal numbers - fortunately | |
4589 | they don't change. */ | |
4590 | sigaddset (set, __SIGRTMIN); | |
4591 | sigaddset (set, __SIGRTMIN + 1); | |
d6b0e80f | 4592 | } |